Initial commit: Linux kernel 4.19 for Unplugged OS

drivers/clocksource/Kconfig

@@ -0,0 +1,646 @@
+menu "Clock Source drivers"
+	depends on GENERIC_CLOCKEVENTS
+
+config TIMER_OF
+	bool
+	select TIMER_PROBE
+
+config TIMER_ACPI
+	bool
+	select TIMER_PROBE
+
+config TIMER_PROBE
+	bool
+
+config CLKSRC_I8253
+	bool
+
+config CLKEVT_I8253
+	bool
+
+config I8253_LOCK
+	bool
+
+config OMAP_DM_TIMER
+	bool
+
+config CLKBLD_I8253
+	def_bool y if CLKSRC_I8253 || CLKEVT_I8253 || I8253_LOCK
+
+config CLKSRC_MMIO
+	bool
+
+config BCM2835_TIMER
+	bool "BCM2835 timer driver" if COMPILE_TEST
+	select CLKSRC_MMIO
+	help
+	  Enables the support for the BCM2835 timer driver.
+
+config BCM_KONA_TIMER
+	bool "BCM mobile timer driver" if COMPILE_TEST
+	select CLKSRC_MMIO
+	help
+	  Enables the support for the BCM Kona mobile timer driver.
+
+config DIGICOLOR_TIMER
+	bool "Digicolor timer driver" if COMPILE_TEST
+	select CLKSRC_MMIO
+	depends on HAS_IOMEM
+	help
+	  Enables the support for the digicolor timer driver.
+
+config DW_APB_TIMER
+	bool "DW APB timer driver" if COMPILE_TEST
+	help
+	  Enables the support for the dw_apb timer.
+
+config DW_APB_TIMER_OF
+	bool
+	select DW_APB_TIMER
+	select TIMER_OF
+
+config FTTMR010_TIMER
+	bool "Faraday Technology timer driver" if COMPILE_TEST
+	depends on HAS_IOMEM
+	select CLKSRC_MMIO
+	select TIMER_OF
+	select MFD_SYSCON
+	help
+	  Enables support for the Faraday Technology timer block
+	  FTTMR010.
+
+config ROCKCHIP_TIMER
+	bool "Rockchip timer driver" if COMPILE_TEST
+	depends on ARM || ARM64
+	select TIMER_OF
+	select CLKSRC_MMIO
+	help
+	  Enables the support for the rockchip timer driver.
+
+config ARMADA_370_XP_TIMER
+	bool "Armada 370 and XP timer driver" if COMPILE_TEST
+	depends on ARM
+	select TIMER_OF
+	select CLKSRC_MMIO
+	help
+	  Enables the support for the Armada 370 and XP timer driver.
+
+config MESON6_TIMER
+	bool "Meson6 timer driver" if COMPILE_TEST
+	select CLKSRC_MMIO
+	help
+	  Enables the support for the Meson6 timer driver.
+
+config ORION_TIMER
+	bool "Orion timer driver" if COMPILE_TEST
+	depends on ARM
+	select TIMER_OF
+	select CLKSRC_MMIO
+	help
+	  Enables the support for the Orion timer driver
+
+config OWL_TIMER
+	bool "Owl timer driver" if COMPILE_TEST
+	select CLKSRC_MMIO
+	help
+	  Enables the support for the Actions Semi Owl timer driver.
+
+config SUN4I_TIMER
+	bool "Sun4i timer driver" if COMPILE_TEST
+	depends on HAS_IOMEM
+	select CLKSRC_MMIO
+	select TIMER_OF
+	help
+	  Enables support for the Sun4i timer.
+
+config SUN5I_HSTIMER
+	bool "Sun5i timer driver" if COMPILE_TEST
+	select CLKSRC_MMIO
+	depends on COMMON_CLK
+	help
+	  Enables support the Sun5i timer.
+
+config TEGRA_TIMER
+	bool "Tegra timer driver" if COMPILE_TEST
+	select CLKSRC_MMIO
+	depends on ARM
+	help
+	  Enables support for the Tegra driver.
+
+config VT8500_TIMER
+	bool "VT8500 timer driver" if COMPILE_TEST
+	depends on HAS_IOMEM
+	help
+	  Enables support for the VT8500 driver.
+
+config NPCM7XX_TIMER
+	bool "NPCM7xx timer driver" if COMPILE_TEST
+	depends on HAS_IOMEM
+	select TIMER_OF
+	select CLKSRC_MMIO
+	help
+	  Enable 24-bit TIMER0 and TIMER1 counters in the NPCM7xx architecture,
+	  While TIMER0 serves as clockevent and TIMER1 serves as clocksource.
+
+config CADENCE_TTC_TIMER
+	bool "Cadence TTC timer driver" if COMPILE_TEST
+	depends on COMMON_CLK
+	help
+	  Enables support for the cadence ttc driver.
+
+config ASM9260_TIMER
+	bool "ASM9260 timer driver" if COMPILE_TEST
+	select CLKSRC_MMIO
+	select TIMER_OF
+	help
+	  Enables support for the ASM9260 timer.
+
+config CLKSRC_NOMADIK_MTU
+	bool "Nomakdik clocksource driver" if COMPILE_TEST
+	depends on ARM
+	select CLKSRC_MMIO
+	help
+	  Support for Multi Timer Unit. MTU provides access
+	  to multiple interrupt generating programmable
+	  32-bit free running decrementing counters.
+
+config CLKSRC_NOMADIK_MTU_SCHED_CLOCK
+	bool
+	depends on CLKSRC_NOMADIK_MTU
+	help
+	  Use the Multi Timer Unit as the sched_clock.
+
+config CLKSRC_DBX500_PRCMU
+	bool "Clocksource PRCMU Timer" if COMPILE_TEST
+	depends on HAS_IOMEM
+	help
+	  Use the always on PRCMU Timer as clocksource
+
+config CLPS711X_TIMER
+	bool "Cirrus logic timer driver" if COMPILE_TEST
+	select CLKSRC_MMIO
+	help
+	  Enables support for the Cirrus Logic PS711 timer.
+
+config ATLAS7_TIMER
+	bool "Atlas7 timer driver" if COMPILE_TEST
+	select CLKSRC_MMIO
+	help
+	  Enables support for the Atlas7 timer.
+
+config MXS_TIMER
+	bool "Mxs timer driver" if COMPILE_TEST
+	select CLKSRC_MMIO
+	select STMP_DEVICE
+	help
+	  Enables support for the Mxs timer.
+
+config PRIMA2_TIMER
+	bool "Prima2 timer driver" if COMPILE_TEST
+	select CLKSRC_MMIO
+	help
+	  Enables support for the Prima2 timer.
+
+config U300_TIMER
+	bool "U300 timer driver" if COMPILE_TEST
+	depends on ARM
+	select CLKSRC_MMIO
+	help
+	  Enables support for the U300 timer.
+
+config NSPIRE_TIMER
+	bool "NSpire timer driver" if COMPILE_TEST
+	select CLKSRC_MMIO
+	help
+	  Enables support for the Nspire timer.
+
+config KEYSTONE_TIMER
+	bool "Keystone timer driver" if COMPILE_TEST
+	depends on ARM || ARM64
+	select CLKSRC_MMIO
+	help
+	  Enables support for the Keystone timer.
+
+config INTEGRATOR_AP_TIMER
+	bool "Integrator-ap timer driver" if COMPILE_TEST
+	select CLKSRC_MMIO
+	help
+	  Enables support for the Integrator-ap timer.
+
+config CLKSRC_DBX500_PRCMU_SCHED_CLOCK
+	bool "Clocksource PRCMU Timer sched_clock"
+	depends on (CLKSRC_DBX500_PRCMU && !CLKSRC_NOMADIK_MTU_SCHED_CLOCK)
+	default y
+	help
+	  Use the always on PRCMU Timer as sched_clock
+
+config CLKSRC_EFM32
+	bool "Clocksource for Energy Micro's EFM32 SoCs" if !ARCH_EFM32
+	depends on OF && ARM && (ARCH_EFM32 || COMPILE_TEST)
+	select CLKSRC_MMIO
+	default ARCH_EFM32
+	help
+	  Support to use the timers of EFM32 SoCs as clock source and clock
+	  event device.
+
+config CLKSRC_LPC32XX
+	bool "Clocksource for LPC32XX" if COMPILE_TEST
+	depends on HAS_IOMEM
+	depends on ARM
+	select CLKSRC_MMIO
+	select TIMER_OF
+	help
+	  Support for the LPC32XX clocksource.
+
+config CLKSRC_PISTACHIO
+	bool "Clocksource for Pistachio SoC" if COMPILE_TEST
+	depends on HAS_IOMEM
+	select TIMER_OF
+	help
+	  Enables the clocksource for the Pistachio SoC.
+
+config CLKSRC_TI_32K
+	bool "Texas Instruments 32.768 Hz Clocksource" if COMPILE_TEST
+	depends on GENERIC_SCHED_CLOCK
+	select TIMER_OF if OF
+	help
+	  This option enables support for Texas Instruments 32.768 Hz clocksource
+	  available on many OMAP-like platforms.
+
+config CLKSRC_NPS
+	bool "NPS400 clocksource driver" if COMPILE_TEST
+	depends on !PHYS_ADDR_T_64BIT
+	select CLKSRC_MMIO
+	select TIMER_OF if OF
+	help
+	  NPS400 clocksource support.
+	  Got 64 bit counter with update rate up to 1000MHz.
+	  This counter is accessed via couple of 32 bit memory mapped registers.
+
+config CLKSRC_STM32
+	bool "Clocksource for STM32 SoCs" if !ARCH_STM32
+	depends on OF && ARM && (ARCH_STM32 || COMPILE_TEST)
+	select CLKSRC_MMIO
+	select TIMER_OF
+
+config CLKSRC_MPS2
+	bool "Clocksource for MPS2 SoCs" if COMPILE_TEST
+	depends on GENERIC_SCHED_CLOCK
+	select CLKSRC_MMIO
+	select TIMER_OF
+
+config ARC_TIMERS
+	bool "Support for 32-bit TIMERn counters in ARC Cores" if COMPILE_TEST
+	depends on GENERIC_SCHED_CLOCK
+	select TIMER_OF
+	help
+	  These are legacy 32-bit TIMER0 and TIMER1 counters found on all ARC cores
+	  (ARC700 as well as ARC HS38).
+	  TIMER0 serves as clockevent while TIMER1 provides clocksource
+
+config ARC_TIMERS_64BIT
+	bool "Support for 64-bit counters in ARC HS38 cores" if COMPILE_TEST
+	depends on ARC_TIMERS
+	select TIMER_OF
+	help
+	  This enables 2 different 64-bit timers: RTC (for UP) and GFRC (for SMP)
+	  RTC is implemented inside the core, while GFRC sits outside the core in
+	  ARConnect IP block. Driver automatically picks one of them for clocksource
+	  as appropriate.
+
+config ARM_ARCH_TIMER
+	bool
+	select TIMER_OF if OF
+	select TIMER_ACPI if ACPI
+
+config ARM_ARCH_TIMER_EVTSTREAM
+	bool "Enable ARM architected timer event stream generation by default"
+	default y if ARM_ARCH_TIMER
+	depends on ARM_ARCH_TIMER
+	help
+	  This option enables support by default for event stream generation
+	  based on the ARM architected timer. It is used for waking up CPUs
+	  executing the wfe instruction at a frequency represented as a
+	  power-of-2 divisor of the clock rate. The behaviour can also be
+	  overridden on the command line using the
+	  clocksource.arm_arch_timer.evtstream parameter.
+	  The main use of the event stream is wfe-based timeouts of userspace
+	  locking implementations. It might also be useful for imposing timeout
+	  on wfe to safeguard against any programming errors in case an expected
+	  event is not generated.
+	  This must be disabled for hardware validation purposes to detect any
+	  hardware anomalies of missing events.
+
+config ARM_ARCH_TIMER_OOL_WORKAROUND
+	bool
+
+config FSL_ERRATUM_A008585
+	bool "Workaround for Freescale/NXP Erratum A-008585"
+	default y
+	depends on ARM_ARCH_TIMER && ARM64
+	select ARM_ARCH_TIMER_OOL_WORKAROUND
+	help
+	  This option enables a workaround for Freescale/NXP Erratum
+	  A-008585 ("ARM generic timer may contain an erroneous
+	  value").  The workaround will only be active if the
+	  fsl,erratum-a008585 property is found in the timer node.
+
+config HISILICON_ERRATUM_161010101
+	bool "Workaround for Hisilicon Erratum 161010101"
+	default y
+	select ARM_ARCH_TIMER_OOL_WORKAROUND
+	depends on ARM_ARCH_TIMER && ARM64
+	help
+	  This option enables a workaround for Hisilicon Erratum
+	  161010101. The workaround will be active if the hisilicon,erratum-161010101
+	  property is found in the timer node.
+
+config ARM64_ERRATUM_858921
+	bool "Workaround for Cortex-A73 erratum 858921"
+	default y
+	select ARM_ARCH_TIMER_OOL_WORKAROUND
+	depends on ARM_ARCH_TIMER && ARM64
+	help
+	  This option enables a workaround applicable to Cortex-A73
+	  (all versions), whose counter may return incorrect values.
+	  The workaround will be dynamically enabled when an affected
+	  core is detected.
+
+config SUN50I_ERRATUM_UNKNOWN1
+	bool "Workaround for Allwinner A64 erratum UNKNOWN1"
+	default y
+	depends on ARM_ARCH_TIMER && ARM64 && ARCH_SUNXI
+	select ARM_ARCH_TIMER_OOL_WORKAROUND
+	help
+	  This option enables a workaround for instability in the timer on
+	  the Allwinner A64 SoC. The workaround will only be active if the
+	  allwinner,erratum-unknown1 property is found in the timer node.
+
+config ARM_GLOBAL_TIMER
+	bool "Support for the ARM global timer" if COMPILE_TEST
+	select TIMER_OF if OF
+	depends on ARM
+	help
+	  This options enables support for the ARM global timer unit
+
+config ARM_TIMER_SP804
+	bool "Support for Dual Timer SP804 module"
+	depends on GENERIC_SCHED_CLOCK && CLKDEV_LOOKUP
+	select CLKSRC_MMIO
+	select TIMER_OF if OF
+
+config CLKSRC_ARM_GLOBAL_TIMER_SCHED_CLOCK
+	bool
+	depends on ARM_GLOBAL_TIMER
+	default y
+	help
+	 Use ARM global timer clock source as sched_clock
+
+config ARMV7M_SYSTICK
+	bool "Support for the ARMv7M system time" if COMPILE_TEST
+	select TIMER_OF if OF
+	select CLKSRC_MMIO
+	help
+	  This options enables support for the ARMv7M system timer unit
+
+config ATMEL_PIT
+	select TIMER_OF if OF
+	def_bool SOC_AT91SAM9 || SOC_SAMA5
+
+config ATMEL_ST
+	bool "Atmel ST timer support" if COMPILE_TEST
+	depends on HAS_IOMEM
+	select TIMER_OF
+	select MFD_SYSCON
+	help
+	  Support for the Atmel ST timer.
+
+config CLKSRC_EXYNOS_MCT
+	bool "Exynos multi core timer driver" if COMPILE_TEST
+	depends on ARM || ARM64
+	help
+	  Support for Multi Core Timer controller on Exynos SoCs.
+
+config CLKSRC_SAMSUNG_PWM
+	bool "PWM timer driver for Samsung S3C, S5P" if COMPILE_TEST
+	depends on HAS_IOMEM
+	help
+	  This is a new clocksource driver for the PWM timer found in
+	  Samsung S3C, S5P and Exynos SoCs, replacing an earlier driver
+	  for all devicetree enabled platforms. This driver will be
+	  needed only on systems that do not have the Exynos MCT available.
+
+config FSL_FTM_TIMER
+	bool "Freescale FlexTimer Module driver" if COMPILE_TEST
+	depends on HAS_IOMEM
+	select CLKSRC_MMIO
+	help
+	  Support for Freescale FlexTimer Module (FTM) timer.
+
+config VF_PIT_TIMER
+	bool
+	select CLKSRC_MMIO
+	help
+	  Support for Period Interrupt Timer on Freescale Vybrid Family SoCs.
+
+config OXNAS_RPS_TIMER
+	bool "Oxford Semiconductor OXNAS RPS Timers driver" if COMPILE_TEST
+	select TIMER_OF
+	select CLKSRC_MMIO
+	help
+	  This enables support for the Oxford Semiconductor OXNAS RPS timers.
+
+config SYS_SUPPORTS_SH_CMT
+        bool
+
+config MTK_TIMER
+	bool "Mediatek timer driver" if COMPILE_TEST
+	depends on HAS_IOMEM
+	select TIMER_OF
+	select CLKSRC_MMIO
+	help
+	  Support for Mediatek timer driver.
+
+config MTK_TIMER_APXGPT_V1
+      bool "Mediatek apxgpt driver" if COMPILE_TEST
+      depends on GENERIC_CLOCKEVENTS && HAS_IOMEM
+      select CLKSRC_OF
+      select CLKSRC_MMIO
+      help
+        Support for Mediatek NON-IPM gpt timer driver.
+        used for tick broadcast.
+        resolve some issue that gpt interrupt masked.
+        add important debug info.
+
+config SPRD_TIMER
+	bool "Spreadtrum timer driver" if EXPERT
+	depends on HAS_IOMEM
+	depends on (ARCH_SPRD || COMPILE_TEST)
+	default ARCH_SPRD
+	select TIMER_OF
+	help
+	  Enables support for the Spreadtrum timer driver.
+
+config SYS_SUPPORTS_SH_MTU2
+        bool
+
+config SYS_SUPPORTS_SH_TMU
+        bool
+
+config SYS_SUPPORTS_EM_STI
+        bool
+
+config CLKSRC_JCORE_PIT
+	bool "J-Core PIT timer driver" if COMPILE_TEST
+	depends on OF
+	depends on HAS_IOMEM
+	select CLKSRC_MMIO
+	help
+	  This enables build of clocksource and clockevent driver for
+	  the integrated PIT in the J-Core synthesizable, open source SoC.
+
+config SH_TIMER_CMT
+	bool "Renesas CMT timer driver" if COMPILE_TEST
+	depends on HAS_IOMEM
+	default SYS_SUPPORTS_SH_CMT
+	help
+	  This enables build of a clocksource and clockevent driver for
+	  the Compare Match Timer (CMT) hardware available in 16/32/48-bit
+	  variants on a wide range of Mobile and Automotive SoCs from Renesas.
+
+config SH_TIMER_MTU2
+	bool "Renesas MTU2 timer driver" if COMPILE_TEST
+	depends on HAS_IOMEM
+	default SYS_SUPPORTS_SH_MTU2
+	help
+	  This enables build of a clockevent driver for the Multi-Function
+	  Timer Pulse Unit 2 (MTU2) hardware available on SoCs from Renesas.
+	  This hardware comes with 16 bit-timer registers.
+
+config RENESAS_OSTM
+	bool "Renesas OSTM timer driver" if COMPILE_TEST
+	select CLKSRC_MMIO
+	help
+	  Enables the support for the Renesas OSTM.
+
+config SH_TIMER_TMU
+	bool "Renesas TMU timer driver" if COMPILE_TEST
+	depends on HAS_IOMEM
+	default SYS_SUPPORTS_SH_TMU
+	help
+	  This enables build of a clocksource and clockevent driver for
+	  the 32-bit Timer Unit (TMU) hardware available on a wide range
+	  SoCs from Renesas.
+
+config EM_TIMER_STI
+	bool "Renesas STI timer driver" if COMPILE_TEST
+	depends on HAS_IOMEM
+	default SYS_SUPPORTS_EM_STI
+	help
+	  This enables build of a clocksource and clockevent driver for
+	  the 48-bit System Timer (STI) hardware available on a SoCs
+	  such as EMEV2 from former NEC Electronics.
+
+config CLKSRC_QCOM
+	bool "Qualcomm MSM timer" if COMPILE_TEST
+	depends on ARM
+	select TIMER_OF
+	help
+	  This enables the clocksource and the per CPU clockevent driver for the
+	  Qualcomm SoCs.
+
+config CLKSRC_VERSATILE
+	bool "ARM Versatile (Express) reference platforms clock source" if COMPILE_TEST
+	depends on GENERIC_SCHED_CLOCK && !ARCH_USES_GETTIMEOFFSET
+	select TIMER_OF
+	default y if MFD_VEXPRESS_SYSREG
+	help
+	  This option enables clock source based on free running
+	  counter available in the "System Registers" block of
+	  ARM Versatile, RealView and Versatile Express reference
+	  platforms.
+
+config CLKSRC_MIPS_GIC
+	bool
+	depends on MIPS_GIC
+	select TIMER_OF
+
+config CLKSRC_TANGO_XTAL
+	bool "Clocksource for Tango SoC" if COMPILE_TEST
+	depends on ARM
+	select TIMER_OF
+	select CLKSRC_MMIO
+	help
+	  This enables the clocksource for Tango SoC
+
+config CLKSRC_PXA
+	bool "Clocksource for PXA or SA-11x0 platform" if COMPILE_TEST
+	depends on HAS_IOMEM
+	select CLKSRC_MMIO
+	help
+	  This enables OST0 support available on PXA and SA-11x0
+	  platforms.
+
+config H8300_TMR8
+        bool "Clockevent timer for the H8300 platform" if COMPILE_TEST
+        depends on HAS_IOMEM
+	help
+	  This enables the 8 bits timer for the H8300 platform.
+
+config H8300_TMR16
+        bool "Clockevent timer for the H83069 platform" if COMPILE_TEST
+        depends on HAS_IOMEM
+	help
+	  This enables the 16 bits timer for the H8300 platform with the
+	  H83069 cpu.
+
+config H8300_TPU
+        bool "Clocksource for the H8300 platform" if COMPILE_TEST
+        depends on HAS_IOMEM
+	help
+	  This enables the clocksource for the H8300 platform with the
+	  H8S2678 cpu.
+
+config CLKSRC_IMX_GPT
+	bool "Clocksource using i.MX GPT" if COMPILE_TEST
+	depends on ARM && CLKDEV_LOOKUP
+	select CLKSRC_MMIO
+
+config CLKSRC_IMX_TPM
+	bool "Clocksource using i.MX TPM" if COMPILE_TEST
+	depends on ARM && CLKDEV_LOOKUP
+	select CLKSRC_MMIO
+	help
+	  Enable this option to use IMX Timer/PWM Module (TPM) timer as
+	  clocksource.
+
+config CLKSRC_ST_LPC
+	bool "Low power clocksource found in the LPC" if COMPILE_TEST
+	select TIMER_OF if OF
+	depends on HAS_IOMEM
+	select CLKSRC_MMIO
+	help
+	  Enable this option to use the Low Power controller timer
+	  as clocksource.
+
+config ATCPIT100_TIMER
+	bool "ATCPIT100 timer driver"
+	depends on NDS32 || COMPILE_TEST
+	depends on HAS_IOMEM
+	select TIMER_OF
+	default NDS32
+	help
+	  This option enables support for the Andestech ATCPIT100 timers.
+
+config RISCV_TIMER
+	bool "Timer for the RISC-V platform"
+	depends on RISCV
+	default y
+	select TIMER_PROBE
+	select TIMER_OF
+	help
+	  This enables the per-hart timer built into all RISC-V systems, which
+	  is accessed via both the SBI and the rdcycle instruction.  This is
+	  required for all RISC-V systems.
+
+endmenu

drivers/clocksource/Makefile

@@ -0,0 +1,86 @@
+# SPDX-License-Identifier: GPL-2.0
+
+# For timer-mediatek debug info
+ccflags-y += -I$(srctree)/drivers/misc/mediatek/include
+
+obj-$(CONFIG_TIMER_OF)		+= timer-of.o
+obj-$(CONFIG_TIMER_PROBE)	+= timer-probe.o
+obj-$(CONFIG_ATMEL_PIT)		+= timer-atmel-pit.o
+obj-$(CONFIG_ATMEL_ST)		+= timer-atmel-st.o
+obj-$(CONFIG_ATMEL_TCB_CLKSRC)	+= tcb_clksrc.o
+obj-$(CONFIG_X86_PM_TIMER)	+= acpi_pm.o
+obj-$(CONFIG_SCx200HR_TIMER)	+= scx200_hrt.o
+obj-$(CONFIG_CS5535_CLOCK_EVENT_SRC)	+= cs5535-clockevt.o
+obj-$(CONFIG_CLKSRC_JCORE_PIT)		+= jcore-pit.o
+obj-$(CONFIG_SH_TIMER_CMT)	+= sh_cmt.o
+obj-$(CONFIG_SH_TIMER_MTU2)	+= sh_mtu2.o
+obj-$(CONFIG_RENESAS_OSTM)	+= renesas-ostm.o
+obj-$(CONFIG_SH_TIMER_TMU)	+= sh_tmu.o
+obj-$(CONFIG_EM_TIMER_STI)	+= em_sti.o
+obj-$(CONFIG_CLKBLD_I8253)	+= i8253.o
+obj-$(CONFIG_CLKSRC_MMIO)	+= mmio.o
+obj-$(CONFIG_DIGICOLOR_TIMER)	+= timer-digicolor.o
+obj-$(CONFIG_OMAP_DM_TIMER)	+= timer-ti-dm.o
+obj-$(CONFIG_DW_APB_TIMER)	+= dw_apb_timer.o
+obj-$(CONFIG_DW_APB_TIMER_OF)	+= dw_apb_timer_of.o
+obj-$(CONFIG_FTTMR010_TIMER)	+= timer-fttmr010.o
+obj-$(CONFIG_ROCKCHIP_TIMER)      += rockchip_timer.o
+obj-$(CONFIG_CLKSRC_NOMADIK_MTU)	+= nomadik-mtu.o
+obj-$(CONFIG_CLKSRC_DBX500_PRCMU)	+= clksrc-dbx500-prcmu.o
+obj-$(CONFIG_ARMADA_370_XP_TIMER)	+= time-armada-370-xp.o
+obj-$(CONFIG_ORION_TIMER)	+= time-orion.o
+obj-$(CONFIG_BCM2835_TIMER)	+= bcm2835_timer.o
+obj-$(CONFIG_CLPS711X_TIMER)	+= clps711x-timer.o
+obj-$(CONFIG_ATLAS7_TIMER)	+= timer-atlas7.o
+obj-$(CONFIG_MXS_TIMER)		+= mxs_timer.o
+obj-$(CONFIG_CLKSRC_PXA)	+= pxa_timer.o
+obj-$(CONFIG_PRIMA2_TIMER)	+= timer-prima2.o
+obj-$(CONFIG_U300_TIMER)	+= timer-u300.o
+obj-$(CONFIG_SUN4I_TIMER)	+= sun4i_timer.o
+obj-$(CONFIG_SUN5I_HSTIMER)	+= timer-sun5i.o
+obj-$(CONFIG_MESON6_TIMER)	+= meson6_timer.o
+obj-$(CONFIG_TEGRA_TIMER)	+= tegra20_timer.o
+obj-$(CONFIG_VT8500_TIMER)	+= vt8500_timer.o
+obj-$(CONFIG_NSPIRE_TIMER)	+= zevio-timer.o
+obj-$(CONFIG_BCM_KONA_TIMER)	+= bcm_kona_timer.o
+obj-$(CONFIG_CADENCE_TTC_TIMER)	+= cadence_ttc_timer.o
+obj-$(CONFIG_CLKSRC_EFM32)	+= time-efm32.o
+obj-$(CONFIG_CLKSRC_STM32)	+= timer-stm32.o
+obj-$(CONFIG_CLKSRC_EXYNOS_MCT)	+= exynos_mct.o
+obj-$(CONFIG_CLKSRC_LPC32XX)	+= time-lpc32xx.o
+obj-$(CONFIG_CLKSRC_MPS2)	+= mps2-timer.o
+obj-$(CONFIG_CLKSRC_SAMSUNG_PWM)	+= samsung_pwm_timer.o
+obj-$(CONFIG_FSL_FTM_TIMER)	+= fsl_ftm_timer.o
+obj-$(CONFIG_VF_PIT_TIMER)	+= vf_pit_timer.o
+obj-$(CONFIG_CLKSRC_QCOM)	+= qcom-timer.o
+obj-$(CONFIG_MTK_TIMER)		+= timer-mediatek.o
+obj-$(CONFIG_MTK_TIMER_APXGPT_V1)	+= mtk_apxgpt.o
+obj-$(CONFIG_CLKSRC_PISTACHIO)	+= time-pistachio.o
+obj-$(CONFIG_CLKSRC_TI_32K)	+= timer-ti-32k.o
+obj-$(CONFIG_CLKSRC_NPS)	+= timer-nps.o
+obj-$(CONFIG_OXNAS_RPS_TIMER)	+= timer-oxnas-rps.o
+obj-$(CONFIG_OWL_TIMER)		+= owl-timer.o
+obj-$(CONFIG_SPRD_TIMER)	+= timer-sprd.o
+obj-$(CONFIG_NPCM7XX_TIMER)	+= timer-npcm7xx.o
+
+obj-$(CONFIG_ARC_TIMERS)		+= arc_timer.o
+obj-$(CONFIG_ARM_ARCH_TIMER)		+= arm_arch_timer.o
+obj-$(CONFIG_ARM_GLOBAL_TIMER)		+= arm_global_timer.o
+obj-$(CONFIG_ARMV7M_SYSTICK)		+= armv7m_systick.o
+obj-$(CONFIG_ARM_TIMER_SP804)		+= timer-sp804.o
+obj-$(CONFIG_ARCH_HAS_TICK_BROADCAST)	+= dummy_timer.o
+obj-$(CONFIG_KEYSTONE_TIMER)		+= timer-keystone.o
+obj-$(CONFIG_INTEGRATOR_AP_TIMER)	+= timer-integrator-ap.o
+obj-$(CONFIG_CLKSRC_VERSATILE)		+= versatile.o
+obj-$(CONFIG_CLKSRC_MIPS_GIC)		+= mips-gic-timer.o
+obj-$(CONFIG_CLKSRC_TANGO_XTAL)		+= tango_xtal.o
+obj-$(CONFIG_CLKSRC_IMX_GPT)		+= timer-imx-gpt.o
+obj-$(CONFIG_CLKSRC_IMX_TPM)		+= timer-imx-tpm.o
+obj-$(CONFIG_ASM9260_TIMER)		+= asm9260_timer.o
+obj-$(CONFIG_H8300_TMR8)		+= h8300_timer8.o
+obj-$(CONFIG_H8300_TMR16)		+= h8300_timer16.o
+obj-$(CONFIG_H8300_TPU)			+= h8300_tpu.o
+obj-$(CONFIG_CLKSRC_ST_LPC)		+= clksrc_st_lpc.o
+obj-$(CONFIG_X86_NUMACHIP)		+= numachip.o
+obj-$(CONFIG_ATCPIT100_TIMER)		+= timer-atcpit100.o
+obj-$(CONFIG_RISCV_TIMER)		+= riscv_timer.o

drivers/clocksource/acpi_pm.c

@@ -0,0 +1,242 @@
+/*
+ * linux/drivers/clocksource/acpi_pm.c
+ *
+ * This file contains the ACPI PM based clocksource.
+ *
+ * This code was largely moved from the i386 timer_pm.c file
+ * which was (C) Dominik Brodowski <linux@brodo.de> 2003
+ * and contained the following comments:
+ *
+ * Driver to use the Power Management Timer (PMTMR) available in some
+ * southbridges as primary timing source for the Linux kernel.
+ *
+ * Based on parts of linux/drivers/acpi/hardware/hwtimer.c, timer_pit.c,
+ * timer_hpet.c, and on Arjan van de Ven's implementation for 2.4.
+ *
+ * This file is licensed under the GPL v2.
+ */
+
+#include <linux/acpi_pmtmr.h>
+#include <linux/clocksource.h>
+#include <linux/timex.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/delay.h>
+#include <asm/io.h>
+
+/*
+ * The I/O port the PMTMR resides at.
+ * The location is detected during setup_arch(),
+ * in arch/i386/kernel/acpi/boot.c
+ */
+u32 pmtmr_ioport __read_mostly;
+
+static inline u32 read_pmtmr(void)
+{
+	/* mask the output to 24 bits */
+	return inl(pmtmr_ioport) & ACPI_PM_MASK;
+}
+
+u32 acpi_pm_read_verified(void)
+{
+	u32 v1 = 0, v2 = 0, v3 = 0;
+
+	/*
+	 * It has been reported that because of various broken
+	 * chipsets (ICH4, PIIX4 and PIIX4E) where the ACPI PM clock
+	 * source is not latched, you must read it multiple
+	 * times to ensure a safe value is read:
+	 */
+	do {
+		v1 = read_pmtmr();
+		v2 = read_pmtmr();
+		v3 = read_pmtmr();
+	} while (unlikely((v1 > v2 && v1 < v3) || (v2 > v3 && v2 < v1)
+			  || (v3 > v1 && v3 < v2)));
+
+	return v2;
+}
+
+static u64 acpi_pm_read(struct clocksource *cs)
+{
+	return (u64)read_pmtmr();
+}
+
+static struct clocksource clocksource_acpi_pm = {
+	.name		= "acpi_pm",
+	.rating		= 200,
+	.read		= acpi_pm_read,
+	.mask		= (u64)ACPI_PM_MASK,
+	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+
+#ifdef CONFIG_PCI
+static int acpi_pm_good;
+static int __init acpi_pm_good_setup(char *__str)
+{
+	acpi_pm_good = 1;
+	return 1;
+}
+__setup("acpi_pm_good", acpi_pm_good_setup);
+
+static u64 acpi_pm_read_slow(struct clocksource *cs)
+{
+	return (u64)acpi_pm_read_verified();
+}
+
+static inline void acpi_pm_need_workaround(void)
+{
+	clocksource_acpi_pm.read = acpi_pm_read_slow;
+	clocksource_acpi_pm.rating = 120;
+}
+
+/*
+ * PIIX4 Errata:
+ *
+ * The power management timer may return improper results when read.
+ * Although the timer value settles properly after incrementing,
+ * while incrementing there is a 3 ns window every 69.8 ns where the
+ * timer value is indeterminate (a 4.2% chance that the data will be
+ * incorrect when read). As a result, the ACPI free running count up
+ * timer specification is violated due to erroneous reads.
+ */
+static void acpi_pm_check_blacklist(struct pci_dev *dev)
+{
+	if (acpi_pm_good)
+		return;
+
+	/* the bug has been fixed in PIIX4M */
+	if (dev->revision < 3) {
+		pr_warn("* Found PM-Timer Bug on the chipset. Due to workarounds for a bug,\n"
+			"* this clock source is slow. Consider trying other clock sources\n");
+
+		acpi_pm_need_workaround();
+	}
+}
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82371AB_3,
+			acpi_pm_check_blacklist);
+
+static void acpi_pm_check_graylist(struct pci_dev *dev)
+{
+	if (acpi_pm_good)
+		return;
+
+	pr_warn("* The chipset may have PM-Timer Bug. Due to workarounds for a bug,\n"
+		"* this clock source is slow. If you are sure your timer does not have\n"
+		"* this bug, please use \"acpi_pm_good\" to disable the workaround\n");
+
+	acpi_pm_need_workaround();
+}
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82801DB_0,
+			acpi_pm_check_graylist);
+DECLARE_PCI_FIXUP_EARLY(PCI_VENDOR_ID_SERVERWORKS, PCI_DEVICE_ID_SERVERWORKS_LE,
+			acpi_pm_check_graylist);
+#endif
+
+#ifndef CONFIG_X86_64
+#include <asm/mach_timer.h>
+#define PMTMR_EXPECTED_RATE \
+  ((CALIBRATE_LATCH * (PMTMR_TICKS_PER_SEC >> 10)) / (PIT_TICK_RATE>>10))
+/*
+ * Some boards have the PMTMR running way too fast. We check
+ * the PMTMR rate against PIT channel 2 to catch these cases.
+ */
+static int verify_pmtmr_rate(void)
+{
+	u64 value1, value2;
+	unsigned long count, delta;
+
+	mach_prepare_counter();
+	value1 = clocksource_acpi_pm.read(&clocksource_acpi_pm);
+	mach_countup(&count);
+	value2 = clocksource_acpi_pm.read(&clocksource_acpi_pm);
+	delta = (value2 - value1) & ACPI_PM_MASK;
+
+	/* Check that the PMTMR delta is within 5% of what we expect */
+	if (delta < (PMTMR_EXPECTED_RATE * 19) / 20 ||
+	    delta > (PMTMR_EXPECTED_RATE * 21) / 20) {
+		pr_info("PM-Timer running at invalid rate: %lu%% of normal - aborting.\n",
+			100UL * delta / PMTMR_EXPECTED_RATE);
+		return -1;
+	}
+
+	return 0;
+}
+#else
+#define verify_pmtmr_rate() (0)
+#endif
+
+/* Number of monotonicity checks to perform during initialization */
+#define ACPI_PM_MONOTONICITY_CHECKS 10
+/* Number of reads we try to get two different values */
+#define ACPI_PM_READ_CHECKS 10000
+
+static int __init init_acpi_pm_clocksource(void)
+{
+	u64 value1, value2;
+	unsigned int i, j = 0;
+
+	if (!pmtmr_ioport)
+		return -ENODEV;
+
+	/* "verify" this timing source: */
+	for (j = 0; j < ACPI_PM_MONOTONICITY_CHECKS; j++) {
+		udelay(100 * j);
+		value1 = clocksource_acpi_pm.read(&clocksource_acpi_pm);
+		for (i = 0; i < ACPI_PM_READ_CHECKS; i++) {
+			value2 = clocksource_acpi_pm.read(&clocksource_acpi_pm);
+			if (value2 == value1)
+				continue;
+			if (value2 > value1)
+				break;
+			if ((value2 < value1) && ((value2) < 0xFFF))
+				break;
+			pr_info("PM-Timer had inconsistent results: %#llx, %#llx - aborting.\n",
+				value1, value2);
+			pmtmr_ioport = 0;
+			return -EINVAL;
+		}
+		if (i == ACPI_PM_READ_CHECKS) {
+			pr_info("PM-Timer failed consistency check  (%#llx) - aborting.\n",
+				value1);
+			pmtmr_ioport = 0;
+			return -ENODEV;
+		}
+	}
+
+	if (verify_pmtmr_rate() != 0){
+		pmtmr_ioport = 0;
+		return -ENODEV;
+	}
+
+	return clocksource_register_hz(&clocksource_acpi_pm,
+						PMTMR_TICKS_PER_SEC);
+}
+
+/* We use fs_initcall because we want the PCI fixups to have run
+ * but we still need to load before device_initcall
+ */
+fs_initcall(init_acpi_pm_clocksource);
+
+/*
+ * Allow an override of the IOPort. Stupid BIOSes do not tell us about
+ * the PMTimer, but we might know where it is.
+ */
+static int __init parse_pmtmr(char *arg)
+{
+	unsigned int base;
+	int ret;
+
+	ret = kstrtouint(arg, 16, &base);
+	if (ret)
+		return ret;
+
+	pr_info("PMTMR IOPort override: 0x%04x -> 0x%04x\n", pmtmr_ioport,
+		base);
+	pmtmr_ioport = base;
+
+	return 1;
+}
+__setup("pmtmr=", parse_pmtmr);

drivers/clocksource/arc_timer.c

@@ -0,0 +1,377 @@
+/*
+ * Copyright (C) 2016-17 Synopsys, Inc. (www.synopsys.com)
+ * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+/* ARC700 has two 32bit independent prog Timers: TIMER0 and TIMER1, Each can be
+ * programmed to go from @count to @limit and optionally interrupt.
+ * We've designated TIMER0 for clockevents and TIMER1 for clocksource
+ *
+ * ARCv2 based HS38 cores have RTC (in-core) and GFRC (inside ARConnect/MCIP)
+ * which are suitable for UP and SMP based clocksources respectively
+ */
+
+#include <linux/interrupt.h>
+#include <linux/clk.h>
+#include <linux/clk-provider.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/cpu.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+
+#include <soc/arc/timers.h>
+#include <soc/arc/mcip.h>
+
+
+static unsigned long arc_timer_freq;
+
+static int noinline arc_get_timer_clk(struct device_node *node)
+{
+	struct clk *clk;
+	int ret;
+
+	clk = of_clk_get(node, 0);
+	if (IS_ERR(clk)) {
+		pr_err("timer missing clk\n");
+		return PTR_ERR(clk);
+	}
+
+	ret = clk_prepare_enable(clk);
+	if (ret) {
+		pr_err("Couldn't enable parent clk\n");
+		return ret;
+	}
+
+	arc_timer_freq = clk_get_rate(clk);
+
+	return 0;
+}
+
+/********** Clock Source Device *********/
+
+#ifdef CONFIG_ARC_TIMERS_64BIT
+
+static u64 arc_read_gfrc(struct clocksource *cs)
+{
+	unsigned long flags;
+	u32 l, h;
+
+	/*
+	 * From a programming model pov, there seems to be just one instance of
+	 * MCIP_CMD/MCIP_READBACK however micro-architecturally there's
+	 * an instance PER ARC CORE (not per cluster), and there are dedicated
+	 * hardware decode logic (per core) inside ARConnect to handle
+	 * simultaneous read/write accesses from cores via those two registers.
+	 * So several concurrent commands to ARConnect are OK if they are
+	 * trying to access two different sub-components (like GFRC,
+	 * inter-core interrupt, etc...). HW also supports simultaneously
+	 * accessing GFRC by multiple cores.
+	 * That's why it is safe to disable hard interrupts on the local CPU
+	 * before access to GFRC instead of taking global MCIP spinlock
+	 * defined in arch/arc/kernel/mcip.c
+	 */
+	local_irq_save(flags);
+
+	__mcip_cmd(CMD_GFRC_READ_LO, 0);
+	l = read_aux_reg(ARC_REG_MCIP_READBACK);
+
+	__mcip_cmd(CMD_GFRC_READ_HI, 0);
+	h = read_aux_reg(ARC_REG_MCIP_READBACK);
+
+	local_irq_restore(flags);
+
+	return (((u64)h) << 32) | l;
+}
+
+static notrace u64 arc_gfrc_clock_read(void)
+{
+	return arc_read_gfrc(NULL);
+}
+
+static struct clocksource arc_counter_gfrc = {
+	.name   = "ARConnect GFRC",
+	.rating = 400,
+	.read   = arc_read_gfrc,
+	.mask   = CLOCKSOURCE_MASK(64),
+	.flags  = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static int __init arc_cs_setup_gfrc(struct device_node *node)
+{
+	struct mcip_bcr mp;
+	int ret;
+
+	READ_BCR(ARC_REG_MCIP_BCR, mp);
+	if (!mp.gfrc) {
+		pr_warn("Global-64-bit-Ctr clocksource not detected\n");
+		return -ENXIO;
+	}
+
+	ret = arc_get_timer_clk(node);
+	if (ret)
+		return ret;
+
+	sched_clock_register(arc_gfrc_clock_read, 64, arc_timer_freq);
+
+	return clocksource_register_hz(&arc_counter_gfrc, arc_timer_freq);
+}
+TIMER_OF_DECLARE(arc_gfrc, "snps,archs-timer-gfrc", arc_cs_setup_gfrc);
+
+#define AUX_RTC_CTRL	0x103
+#define AUX_RTC_LOW	0x104
+#define AUX_RTC_HIGH	0x105
+
+static u64 arc_read_rtc(struct clocksource *cs)
+{
+	unsigned long status;
+	u32 l, h;
+
+	/*
+	 * hardware has an internal state machine which tracks readout of
+	 * low/high and updates the CTRL.status if
+	 *  - interrupt/exception taken between the two reads
+	 *  - high increments after low has been read
+	 */
+	do {
+		l = read_aux_reg(AUX_RTC_LOW);
+		h = read_aux_reg(AUX_RTC_HIGH);
+		status = read_aux_reg(AUX_RTC_CTRL);
+	} while (!(status & _BITUL(31)));
+
+	return (((u64)h) << 32) | l;
+}
+
+static notrace u64 arc_rtc_clock_read(void)
+{
+	return arc_read_rtc(NULL);
+}
+
+static struct clocksource arc_counter_rtc = {
+	.name   = "ARCv2 RTC",
+	.rating = 350,
+	.read   = arc_read_rtc,
+	.mask   = CLOCKSOURCE_MASK(64),
+	.flags  = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static int __init arc_cs_setup_rtc(struct device_node *node)
+{
+	struct bcr_timer timer;
+	int ret;
+
+	READ_BCR(ARC_REG_TIMERS_BCR, timer);
+	if (!timer.rtc) {
+		pr_warn("Local-64-bit-Ctr clocksource not detected\n");
+		return -ENXIO;
+	}
+
+	/* Local to CPU hence not usable in SMP */
+	if (IS_ENABLED(CONFIG_SMP)) {
+		pr_warn("Local-64-bit-Ctr not usable in SMP\n");
+		return -EINVAL;
+	}
+
+	ret = arc_get_timer_clk(node);
+	if (ret)
+		return ret;
+
+	write_aux_reg(AUX_RTC_CTRL, 1);
+
+	sched_clock_register(arc_rtc_clock_read, 64, arc_timer_freq);
+
+	return clocksource_register_hz(&arc_counter_rtc, arc_timer_freq);
+}
+TIMER_OF_DECLARE(arc_rtc, "snps,archs-timer-rtc", arc_cs_setup_rtc);
+
+#endif
+
+/*
+ * 32bit TIMER1 to keep counting monotonically and wraparound
+ */
+
+static u64 arc_read_timer1(struct clocksource *cs)
+{
+	return (u64) read_aux_reg(ARC_REG_TIMER1_CNT);
+}
+
+static notrace u64 arc_timer1_clock_read(void)
+{
+	return arc_read_timer1(NULL);
+}
+
+static struct clocksource arc_counter_timer1 = {
+	.name   = "ARC Timer1",
+	.rating = 300,
+	.read   = arc_read_timer1,
+	.mask   = CLOCKSOURCE_MASK(32),
+	.flags  = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static int __init arc_cs_setup_timer1(struct device_node *node)
+{
+	int ret;
+
+	/* Local to CPU hence not usable in SMP */
+	if (IS_ENABLED(CONFIG_SMP))
+		return -EINVAL;
+
+	ret = arc_get_timer_clk(node);
+	if (ret)
+		return ret;
+
+	write_aux_reg(ARC_REG_TIMER1_LIMIT, ARC_TIMERN_MAX);
+	write_aux_reg(ARC_REG_TIMER1_CNT, 0);
+	write_aux_reg(ARC_REG_TIMER1_CTRL, TIMER_CTRL_NH);
+
+	sched_clock_register(arc_timer1_clock_read, 32, arc_timer_freq);
+
+	return clocksource_register_hz(&arc_counter_timer1, arc_timer_freq);
+}
+
+/********** Clock Event Device *********/
+
+static int arc_timer_irq;
+
+/*
+ * Arm the timer to interrupt after @cycles
+ * The distinction for oneshot/periodic is done in arc_event_timer_ack() below
+ */
+static void arc_timer_event_setup(unsigned int cycles)
+{
+	write_aux_reg(ARC_REG_TIMER0_LIMIT, cycles);
+	write_aux_reg(ARC_REG_TIMER0_CNT, 0);	/* start from 0 */
+
+	write_aux_reg(ARC_REG_TIMER0_CTRL, TIMER_CTRL_IE | TIMER_CTRL_NH);
+}
+
+
+static int arc_clkevent_set_next_event(unsigned long delta,
+				       struct clock_event_device *dev)
+{
+	arc_timer_event_setup(delta);
+	return 0;
+}
+
+static int arc_clkevent_set_periodic(struct clock_event_device *dev)
+{
+	/*
+	 * At X Hz, 1 sec = 1000ms -> X cycles;
+	 *		      10ms -> X / 100 cycles
+	 */
+	arc_timer_event_setup(arc_timer_freq / HZ);
+	return 0;
+}
+
+static DEFINE_PER_CPU(struct clock_event_device, arc_clockevent_device) = {
+	.name			= "ARC Timer0",
+	.features		= CLOCK_EVT_FEAT_ONESHOT |
+				  CLOCK_EVT_FEAT_PERIODIC,
+	.rating			= 300,
+	.set_next_event		= arc_clkevent_set_next_event,
+	.set_state_periodic	= arc_clkevent_set_periodic,
+};
+
+static irqreturn_t timer_irq_handler(int irq, void *dev_id)
+{
+	/*
+	 * Note that generic IRQ core could have passed @evt for @dev_id if
+	 * irq_set_chip_and_handler() asked for handle_percpu_devid_irq()
+	 */
+	struct clock_event_device *evt = this_cpu_ptr(&arc_clockevent_device);
+	int irq_reenable = clockevent_state_periodic(evt);
+
+	/*
+	 * 1. ACK the interrupt
+	 *    - For ARC700, any write to CTRL reg ACKs it, so just rewrite
+	 *      Count when [N]ot [H]alted bit.
+	 *    - For HS3x, it is a bit subtle. On taken count-down interrupt,
+	 *      IP bit [3] is set, which needs to be cleared for ACK'ing.
+	 *      The write below can only update the other two bits, hence
+	 *      explicitly clears IP bit
+	 * 2. Re-arm interrupt if periodic by writing to IE bit [0]
+	 */
+	write_aux_reg(ARC_REG_TIMER0_CTRL, irq_reenable | TIMER_CTRL_NH);
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+
+static int arc_timer_starting_cpu(unsigned int cpu)
+{
+	struct clock_event_device *evt = this_cpu_ptr(&arc_clockevent_device);
+
+	evt->cpumask = cpumask_of(smp_processor_id());
+
+	clockevents_config_and_register(evt, arc_timer_freq, 0, ARC_TIMERN_MAX);
+	enable_percpu_irq(arc_timer_irq, 0);
+	return 0;
+}
+
+static int arc_timer_dying_cpu(unsigned int cpu)
+{
+	disable_percpu_irq(arc_timer_irq);
+	return 0;
+}
+
+/*
+ * clockevent setup for boot CPU
+ */
+static int __init arc_clockevent_setup(struct device_node *node)
+{
+	struct clock_event_device *evt = this_cpu_ptr(&arc_clockevent_device);
+	int ret;
+
+	arc_timer_irq = irq_of_parse_and_map(node, 0);
+	if (arc_timer_irq <= 0) {
+		pr_err("clockevent: missing irq\n");
+		return -EINVAL;
+	}
+
+	ret = arc_get_timer_clk(node);
+	if (ret) {
+		pr_err("clockevent: missing clk\n");
+		return ret;
+	}
+
+	/* Needs apriori irq_set_percpu_devid() done in intc map function */
+	ret = request_percpu_irq(arc_timer_irq, timer_irq_handler,
+				 "Timer0 (per-cpu-tick)", evt);
+	if (ret) {
+		pr_err("clockevent: unable to request irq\n");
+		return ret;
+	}
+
+	ret = cpuhp_setup_state(CPUHP_AP_ARC_TIMER_STARTING,
+				"clockevents/arc/timer:starting",
+				arc_timer_starting_cpu,
+				arc_timer_dying_cpu);
+	if (ret) {
+		pr_err("Failed to setup hotplug state\n");
+		return ret;
+	}
+	return 0;
+}
+
+static int __init arc_of_timer_init(struct device_node *np)
+{
+	static int init_count = 0;
+	int ret;
+
+	if (!init_count) {
+		init_count = 1;
+		ret = arc_clockevent_setup(np);
+	} else {
+		ret = arc_cs_setup_timer1(np);
+	}
+
+	return ret;
+}
+TIMER_OF_DECLARE(arc_clkevt, "snps,arc-timer", arc_of_timer_init);

drivers/clocksource/arm_global_timer.c

@@ -0,0 +1,343 @@
+/*
+ * drivers/clocksource/arm_global_timer.c
+ *
+ * Copyright (C) 2013 STMicroelectronics (R&D) Limited.
+ * Author: Stuart Menefy <stuart.menefy@st.com>
+ * Author: Srinivas Kandagatla <srinivas.kandagatla@st.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/cpu.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/sched_clock.h>
+
+#include <asm/cputype.h>
+
+#define GT_COUNTER0	0x00
+#define GT_COUNTER1	0x04
+
+#define GT_CONTROL	0x08
+#define GT_CONTROL_TIMER_ENABLE		BIT(0)  /* this bit is NOT banked */
+#define GT_CONTROL_COMP_ENABLE		BIT(1)	/* banked */
+#define GT_CONTROL_IRQ_ENABLE		BIT(2)	/* banked */
+#define GT_CONTROL_AUTO_INC		BIT(3)	/* banked */
+
+#define GT_INT_STATUS	0x0c
+#define GT_INT_STATUS_EVENT_FLAG	BIT(0)
+
+#define GT_COMP0	0x10
+#define GT_COMP1	0x14
+#define GT_AUTO_INC	0x18
+
+/*
+ * We are expecting to be clocked by the ARM peripheral clock.
+ *
+ * Note: it is assumed we are using a prescaler value of zero, so this is
+ * the units for all operations.
+ */
+static void __iomem *gt_base;
+static unsigned long gt_clk_rate;
+static int gt_ppi;
+static struct clock_event_device __percpu *gt_evt;
+
+/*
+ * To get the value from the Global Timer Counter register proceed as follows:
+ * 1. Read the upper 32-bit timer counter register
+ * 2. Read the lower 32-bit timer counter register
+ * 3. Read the upper 32-bit timer counter register again. If the value is
+ *  different to the 32-bit upper value read previously, go back to step 2.
+ *  Otherwise the 64-bit timer counter value is correct.
+ */
+static u64 notrace _gt_counter_read(void)
+{
+	u64 counter;
+	u32 lower;
+	u32 upper, old_upper;
+
+	upper = readl_relaxed(gt_base + GT_COUNTER1);
+	do {
+		old_upper = upper;
+		lower = readl_relaxed(gt_base + GT_COUNTER0);
+		upper = readl_relaxed(gt_base + GT_COUNTER1);
+	} while (upper != old_upper);
+
+	counter = upper;
+	counter <<= 32;
+	counter |= lower;
+	return counter;
+}
+
+static u64 gt_counter_read(void)
+{
+	return _gt_counter_read();
+}
+
+/**
+ * To ensure that updates to comparator value register do not set the
+ * Interrupt Status Register proceed as follows:
+ * 1. Clear the Comp Enable bit in the Timer Control Register.
+ * 2. Write the lower 32-bit Comparator Value Register.
+ * 3. Write the upper 32-bit Comparator Value Register.
+ * 4. Set the Comp Enable bit and, if necessary, the IRQ enable bit.
+ */
+static void gt_compare_set(unsigned long delta, int periodic)
+{
+	u64 counter = gt_counter_read();
+	unsigned long ctrl;
+
+	counter += delta;
+	ctrl = GT_CONTROL_TIMER_ENABLE;
+	writel_relaxed(ctrl, gt_base + GT_CONTROL);
+	writel_relaxed(lower_32_bits(counter), gt_base + GT_COMP0);
+	writel_relaxed(upper_32_bits(counter), gt_base + GT_COMP1);
+
+	if (periodic) {
+		writel_relaxed(delta, gt_base + GT_AUTO_INC);
+		ctrl |= GT_CONTROL_AUTO_INC;
+	}
+
+	ctrl |= GT_CONTROL_COMP_ENABLE | GT_CONTROL_IRQ_ENABLE;
+	writel_relaxed(ctrl, gt_base + GT_CONTROL);
+}
+
+static int gt_clockevent_shutdown(struct clock_event_device *evt)
+{
+	unsigned long ctrl;
+
+	ctrl = readl(gt_base + GT_CONTROL);
+	ctrl &= ~(GT_CONTROL_COMP_ENABLE | GT_CONTROL_IRQ_ENABLE |
+		  GT_CONTROL_AUTO_INC);
+	writel(ctrl, gt_base + GT_CONTROL);
+	return 0;
+}
+
+static int gt_clockevent_set_periodic(struct clock_event_device *evt)
+{
+	gt_compare_set(DIV_ROUND_CLOSEST(gt_clk_rate, HZ), 1);
+	return 0;
+}
+
+static int gt_clockevent_set_next_event(unsigned long evt,
+					struct clock_event_device *unused)
+{
+	gt_compare_set(evt, 0);
+	return 0;
+}
+
+static irqreturn_t gt_clockevent_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	if (!(readl_relaxed(gt_base + GT_INT_STATUS) &
+				GT_INT_STATUS_EVENT_FLAG))
+		return IRQ_NONE;
+
+	/**
+	 * ERRATA 740657( Global Timer can send 2 interrupts for
+	 * the same event in single-shot mode)
+	 * Workaround:
+	 *	Either disable single-shot mode.
+	 *	Or
+	 *	Modify the Interrupt Handler to avoid the
+	 *	offending sequence. This is achieved by clearing
+	 *	the Global Timer flag _after_ having incremented
+	 *	the Comparator register	value to a higher value.
+	 */
+	if (clockevent_state_oneshot(evt))
+		gt_compare_set(ULONG_MAX, 0);
+
+	writel_relaxed(GT_INT_STATUS_EVENT_FLAG, gt_base + GT_INT_STATUS);
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static int gt_starting_cpu(unsigned int cpu)
+{
+	struct clock_event_device *clk = this_cpu_ptr(gt_evt);
+
+	clk->name = "arm_global_timer";
+	clk->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT |
+		CLOCK_EVT_FEAT_PERCPU;
+	clk->set_state_shutdown = gt_clockevent_shutdown;
+	clk->set_state_periodic = gt_clockevent_set_periodic;
+	clk->set_state_oneshot = gt_clockevent_shutdown;
+	clk->set_state_oneshot_stopped = gt_clockevent_shutdown;
+	clk->set_next_event = gt_clockevent_set_next_event;
+	clk->cpumask = cpumask_of(cpu);
+	clk->rating = 300;
+	clk->irq = gt_ppi;
+	clockevents_config_and_register(clk, gt_clk_rate,
+					1, 0xffffffff);
+	enable_percpu_irq(clk->irq, IRQ_TYPE_NONE);
+	return 0;
+}
+
+static int gt_dying_cpu(unsigned int cpu)
+{
+	struct clock_event_device *clk = this_cpu_ptr(gt_evt);
+
+	gt_clockevent_shutdown(clk);
+	disable_percpu_irq(clk->irq);
+	return 0;
+}
+
+static u64 gt_clocksource_read(struct clocksource *cs)
+{
+	return gt_counter_read();
+}
+
+static void gt_resume(struct clocksource *cs)
+{
+	unsigned long ctrl;
+
+	ctrl = readl(gt_base + GT_CONTROL);
+	if (!(ctrl & GT_CONTROL_TIMER_ENABLE))
+		/* re-enable timer on resume */
+		writel(GT_CONTROL_TIMER_ENABLE, gt_base + GT_CONTROL);
+}
+
+static struct clocksource gt_clocksource = {
+	.name	= "arm_global_timer",
+	.rating	= 300,
+	.read	= gt_clocksource_read,
+	.mask	= CLOCKSOURCE_MASK(64),
+	.flags	= CLOCK_SOURCE_IS_CONTINUOUS,
+	.resume = gt_resume,
+};
+
+#ifdef CONFIG_CLKSRC_ARM_GLOBAL_TIMER_SCHED_CLOCK
+static u64 notrace gt_sched_clock_read(void)
+{
+	return _gt_counter_read();
+}
+#endif
+
+static unsigned long gt_read_long(void)
+{
+	return readl_relaxed(gt_base + GT_COUNTER0);
+}
+
+static struct delay_timer gt_delay_timer = {
+	.read_current_timer = gt_read_long,
+};
+
+static void __init gt_delay_timer_init(void)
+{
+	gt_delay_timer.freq = gt_clk_rate;
+	register_current_timer_delay(&gt_delay_timer);
+}
+
+static int __init gt_clocksource_init(void)
+{
+	writel(0, gt_base + GT_CONTROL);
+	writel(0, gt_base + GT_COUNTER0);
+	writel(0, gt_base + GT_COUNTER1);
+	/* enables timer on all the cores */
+	writel(GT_CONTROL_TIMER_ENABLE, gt_base + GT_CONTROL);
+
+#ifdef CONFIG_CLKSRC_ARM_GLOBAL_TIMER_SCHED_CLOCK
+	sched_clock_register(gt_sched_clock_read, 64, gt_clk_rate);
+#endif
+	return clocksource_register_hz(&gt_clocksource, gt_clk_rate);
+}
+
+static int __init global_timer_of_register(struct device_node *np)
+{
+	struct clk *gt_clk;
+	int err = 0;
+
+	/*
+	 * In A9 r2p0 the comparators for each processor with the global timer
+	 * fire when the timer value is greater than or equal to. In previous
+	 * revisions the comparators fired when the timer value was equal to.
+	 */
+	if (read_cpuid_part() == ARM_CPU_PART_CORTEX_A9
+	    && (read_cpuid_id() & 0xf0000f) < 0x200000) {
+		pr_warn("global-timer: non support for this cpu version.\n");
+		return -ENOSYS;
+	}
+
+	gt_ppi = irq_of_parse_and_map(np, 0);
+	if (!gt_ppi) {
+		pr_warn("global-timer: unable to parse irq\n");
+		return -EINVAL;
+	}
+
+	gt_base = of_iomap(np, 0);
+	if (!gt_base) {
+		pr_warn("global-timer: invalid base address\n");
+		return -ENXIO;
+	}
+
+	gt_clk = of_clk_get(np, 0);
+	if (!IS_ERR(gt_clk)) {
+		err = clk_prepare_enable(gt_clk);
+		if (err)
+			goto out_unmap;
+	} else {
+		pr_warn("global-timer: clk not found\n");
+		err = -EINVAL;
+		goto out_unmap;
+	}
+
+	gt_clk_rate = clk_get_rate(gt_clk);
+	gt_evt = alloc_percpu(struct clock_event_device);
+	if (!gt_evt) {
+		pr_warn("global-timer: can't allocate memory\n");
+		err = -ENOMEM;
+		goto out_clk;
+	}
+
+	err = request_percpu_irq(gt_ppi, gt_clockevent_interrupt,
+				 "gt", gt_evt);
+	if (err) {
+		pr_warn("global-timer: can't register interrupt %d (%d)\n",
+			gt_ppi, err);
+		goto out_free;
+	}
+
+	/* Register and immediately configure the timer on the boot CPU */
+	err = gt_clocksource_init();
+	if (err)
+		goto out_irq;
+	
+	err = cpuhp_setup_state(CPUHP_AP_ARM_GLOBAL_TIMER_STARTING,
+				"clockevents/arm/global_timer:starting",
+				gt_starting_cpu, gt_dying_cpu);
+	if (err)
+		goto out_irq;
+
+	gt_delay_timer_init();
+
+	return 0;
+
+out_irq:
+	free_percpu_irq(gt_ppi, gt_evt);
+out_free:
+	free_percpu(gt_evt);
+out_clk:
+	clk_disable_unprepare(gt_clk);
+out_unmap:
+	iounmap(gt_base);
+	WARN(err, "ARM Global timer register failed (%d)\n", err);
+
+	return err;
+}
+
+/* Only tested on r2p2 and r3p0  */
+TIMER_OF_DECLARE(arm_gt, "arm,cortex-a9-global-timer",
+			global_timer_of_register);

drivers/clocksource/armv7m_systick.c

@@ -0,0 +1,86 @@
+/*
+ * Copyright (C) Maxime Coquelin 2015
+ * Author:  Maxime Coquelin <mcoquelin.stm32@gmail.com>
+ * License terms:  GNU General Public License (GPL), version 2
+ */
+
+#include <linux/kernel.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/clk.h>
+#include <linux/bitops.h>
+
+#define SYST_CSR	0x00
+#define SYST_RVR	0x04
+#define SYST_CVR	0x08
+#define SYST_CALIB	0x0c
+
+#define SYST_CSR_ENABLE BIT(0)
+
+#define SYSTICK_LOAD_RELOAD_MASK 0x00FFFFFF
+
+static int __init system_timer_of_register(struct device_node *np)
+{
+	struct clk *clk = NULL;
+	void __iomem *base;
+	u32 rate;
+	int ret;
+
+	base = of_iomap(np, 0);
+	if (!base) {
+		pr_warn("system-timer: invalid base address\n");
+		return -ENXIO;
+	}
+
+	ret = of_property_read_u32(np, "clock-frequency", &rate);
+	if (ret) {
+		clk = of_clk_get(np, 0);
+		if (IS_ERR(clk)) {
+			ret = PTR_ERR(clk);
+			goto out_unmap;
+		}
+
+		ret = clk_prepare_enable(clk);
+		if (ret)
+			goto out_clk_put;
+
+		rate = clk_get_rate(clk);
+		if (!rate) {
+			ret = -EINVAL;
+			goto out_clk_disable;
+		}
+	}
+
+	writel_relaxed(SYSTICK_LOAD_RELOAD_MASK, base + SYST_RVR);
+	writel_relaxed(SYST_CSR_ENABLE, base + SYST_CSR);
+
+	ret = clocksource_mmio_init(base + SYST_CVR, "arm_system_timer", rate,
+			200, 24, clocksource_mmio_readl_down);
+	if (ret) {
+		pr_err("failed to init clocksource (%d)\n", ret);
+		if (clk)
+			goto out_clk_disable;
+		else
+			goto out_unmap;
+	}
+
+	pr_info("ARM System timer initialized as clocksource\n");
+
+	return 0;
+
+out_clk_disable:
+	clk_disable_unprepare(clk);
+out_clk_put:
+	clk_put(clk);
+out_unmap:
+	iounmap(base);
+	pr_warn("ARM System timer register failed (%d)\n", ret);
+
+	return ret;
+}
+
+TIMER_OF_DECLARE(arm_systick, "arm,armv7m-systick",
+			system_timer_of_register);

drivers/clocksource/asm9260_timer.c

@@ -0,0 +1,246 @@
+/*
+ * Copyright (C) 2014 Oleksij Rempel <linux@rempel-privat.de>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/sched.h>
+#include <linux/clk.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/bitops.h>
+
+#define DRIVER_NAME	"asm9260-timer"
+
+/*
+ * this device provide 4 offsets for each register:
+ * 0x0 - plain read write mode
+ * 0x4 - set mode, OR logic.
+ * 0x8 - clr mode, XOR logic.
+ * 0xc - togle mode.
+ */
+#define SET_REG 4
+#define CLR_REG 8
+
+#define HW_IR           0x0000 /* RW. Interrupt */
+#define BM_IR_CR0	BIT(4)
+#define BM_IR_MR3	BIT(3)
+#define BM_IR_MR2	BIT(2)
+#define BM_IR_MR1	BIT(1)
+#define BM_IR_MR0	BIT(0)
+
+#define HW_TCR		0x0010 /* RW. Timer controller */
+/* BM_C*_RST
+ * Timer Counter and the Prescale Counter are synchronously reset on the
+ * next positive edge of PCLK. The counters remain reset until TCR[1] is
+ * returned to zero. */
+#define BM_C3_RST	BIT(7)
+#define BM_C2_RST	BIT(6)
+#define BM_C1_RST	BIT(5)
+#define BM_C0_RST	BIT(4)
+/* BM_C*_EN
+ * 1 - Timer Counter and Prescale Counter are enabled for counting
+ * 0 - counters are disabled */
+#define BM_C3_EN	BIT(3)
+#define BM_C2_EN	BIT(2)
+#define BM_C1_EN	BIT(1)
+#define BM_C0_EN	BIT(0)
+
+#define HW_DIR		0x0020 /* RW. Direction? */
+/* 00 - count up
+ * 01 - count down
+ * 10 - ?? 2^n/2 */
+#define BM_DIR_COUNT_UP		0
+#define BM_DIR_COUNT_DOWN	1
+#define BM_DIR0_SHIFT	0
+#define BM_DIR1_SHIFT	4
+#define BM_DIR2_SHIFT	8
+#define BM_DIR3_SHIFT	12
+#define BM_DIR_DEFAULT		(BM_DIR_COUNT_UP << BM_DIR0_SHIFT | \
+				 BM_DIR_COUNT_UP << BM_DIR1_SHIFT | \
+				 BM_DIR_COUNT_UP << BM_DIR2_SHIFT | \
+				 BM_DIR_COUNT_UP << BM_DIR3_SHIFT)
+
+#define HW_TC0		0x0030 /* RO. Timer counter 0 */
+/* HW_TC*. Timer counter owerflow (0xffff.ffff to 0x0000.0000) do not generate
+ * interrupt. This registers can be used to detect overflow */
+#define HW_TC1          0x0040
+#define HW_TC2		0x0050
+#define HW_TC3		0x0060
+
+#define HW_PR		0x0070 /* RW. prescaler */
+#define BM_PR_DISABLE	0
+#define HW_PC		0x0080 /* RO. Prescaler counter */
+#define HW_MCR		0x0090 /* RW. Match control */
+/* enable interrupt on match */
+#define BM_MCR_INT_EN(n)	(1 << (n * 3 + 0))
+/* enable TC reset on match */
+#define BM_MCR_RES_EN(n)	(1 << (n * 3 + 1))
+/* enable stop TC on match */
+#define BM_MCR_STOP_EN(n)	(1 << (n * 3 + 2))
+
+#define HW_MR0		0x00a0 /* RW. Match reg */
+#define HW_MR1		0x00b0
+#define HW_MR2		0x00C0
+#define HW_MR3		0x00D0
+
+#define HW_CTCR		0x0180 /* Counter control */
+#define BM_CTCR0_SHIFT	0
+#define BM_CTCR1_SHIFT	2
+#define BM_CTCR2_SHIFT	4
+#define BM_CTCR3_SHIFT	6
+#define BM_CTCR_TM	0	/* Timer mode. Every rising PCLK edge. */
+#define BM_CTCR_DEFAULT	(BM_CTCR_TM << BM_CTCR0_SHIFT | \
+			 BM_CTCR_TM << BM_CTCR1_SHIFT | \
+			 BM_CTCR_TM << BM_CTCR2_SHIFT | \
+			 BM_CTCR_TM << BM_CTCR3_SHIFT)
+
+static struct asm9260_timer_priv {
+	void __iomem *base;
+	unsigned long ticks_per_jiffy;
+} priv;
+
+static int asm9260_timer_set_next_event(unsigned long delta,
+					 struct clock_event_device *evt)
+{
+	/* configure match count for TC0 */
+	writel_relaxed(delta, priv.base + HW_MR0);
+	/* enable TC0 */
+	writel_relaxed(BM_C0_EN, priv.base + HW_TCR + SET_REG);
+	return 0;
+}
+
+static inline void __asm9260_timer_shutdown(struct clock_event_device *evt)
+{
+	/* stop timer0 */
+	writel_relaxed(BM_C0_EN, priv.base + HW_TCR + CLR_REG);
+}
+
+static int asm9260_timer_shutdown(struct clock_event_device *evt)
+{
+	__asm9260_timer_shutdown(evt);
+	return 0;
+}
+
+static int asm9260_timer_set_oneshot(struct clock_event_device *evt)
+{
+	__asm9260_timer_shutdown(evt);
+
+	/* enable reset and stop on match */
+	writel_relaxed(BM_MCR_RES_EN(0) | BM_MCR_STOP_EN(0),
+		       priv.base + HW_MCR + SET_REG);
+	return 0;
+}
+
+static int asm9260_timer_set_periodic(struct clock_event_device *evt)
+{
+	__asm9260_timer_shutdown(evt);
+
+	/* disable reset and stop on match */
+	writel_relaxed(BM_MCR_RES_EN(0) | BM_MCR_STOP_EN(0),
+		       priv.base + HW_MCR + CLR_REG);
+	/* configure match count for TC0 */
+	writel_relaxed(priv.ticks_per_jiffy, priv.base + HW_MR0);
+	/* enable TC0 */
+	writel_relaxed(BM_C0_EN, priv.base + HW_TCR + SET_REG);
+	return 0;
+}
+
+static struct clock_event_device event_dev = {
+	.name			= DRIVER_NAME,
+	.rating			= 200,
+	.features		= CLOCK_EVT_FEAT_PERIODIC |
+				  CLOCK_EVT_FEAT_ONESHOT,
+	.set_next_event		= asm9260_timer_set_next_event,
+	.set_state_shutdown	= asm9260_timer_shutdown,
+	.set_state_periodic	= asm9260_timer_set_periodic,
+	.set_state_oneshot	= asm9260_timer_set_oneshot,
+	.tick_resume		= asm9260_timer_shutdown,
+};
+
+static irqreturn_t asm9260_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	evt->event_handler(evt);
+
+	writel_relaxed(BM_IR_MR0, priv.base + HW_IR);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * ---------------------------------------------------------------------------
+ * Timer initialization
+ * ---------------------------------------------------------------------------
+ */
+static int __init asm9260_timer_init(struct device_node *np)
+{
+	int irq;
+	struct clk *clk;
+	int ret;
+	unsigned long rate;
+
+	priv.base = of_io_request_and_map(np, 0, np->name);
+	if (IS_ERR(priv.base)) {
+		pr_err("%s: unable to map resource\n", np->name);
+		return PTR_ERR(priv.base);
+	}
+
+	clk = of_clk_get(np, 0);
+	if (IS_ERR(clk)) {
+		pr_err("Failed to get clk!\n");
+		return PTR_ERR(clk);
+	}
+
+	ret = clk_prepare_enable(clk);
+	if (ret) {
+		pr_err("Failed to enable clk!\n");
+		return ret;
+	}
+
+	irq = irq_of_parse_and_map(np, 0);
+	ret = request_irq(irq, asm9260_timer_interrupt, IRQF_TIMER,
+			DRIVER_NAME, &event_dev);
+	if (ret) {
+		pr_err("Failed to setup irq!\n");
+		return ret;
+	}
+
+	/* set all timers for count-up */
+	writel_relaxed(BM_DIR_DEFAULT, priv.base + HW_DIR);
+	/* disable divider */
+	writel_relaxed(BM_PR_DISABLE, priv.base + HW_PR);
+	/* make sure all timers use every rising PCLK edge. */
+	writel_relaxed(BM_CTCR_DEFAULT, priv.base + HW_CTCR);
+	/* enable interrupt for TC0 and clean setting for all other lines */
+	writel_relaxed(BM_MCR_INT_EN(0) , priv.base + HW_MCR);
+
+	rate = clk_get_rate(clk);
+	clocksource_mmio_init(priv.base + HW_TC1, DRIVER_NAME, rate,
+			200, 32, clocksource_mmio_readl_up);
+
+	/* Seems like we can't use counter without match register even if
+	 * actions for MR are disabled. So, set MR to max value. */
+	writel_relaxed(0xffffffff, priv.base + HW_MR1);
+	/* enable TC1 */
+	writel_relaxed(BM_C1_EN, priv.base + HW_TCR + SET_REG);
+
+	priv.ticks_per_jiffy = DIV_ROUND_CLOSEST(rate, HZ);
+	event_dev.cpumask = cpumask_of(0);
+	clockevents_config_and_register(&event_dev, rate, 0x2c00, 0xfffffffe);
+
+	return 0;
+}
+TIMER_OF_DECLARE(asm9260_timer, "alphascale,asm9260-timer",
+		asm9260_timer_init);

drivers/clocksource/bcm2835_timer.c

@@ -0,0 +1,154 @@
+/*
+ * Copyright 2012 Simon Arlott
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/bitops.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/interrupt.h>
+#include <linux/irqreturn.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/slab.h>
+#include <linux/string.h>
+#include <linux/sched_clock.h>
+
+#include <asm/irq.h>
+
+#define REG_CONTROL	0x00
+#define REG_COUNTER_LO	0x04
+#define REG_COUNTER_HI	0x08
+#define REG_COMPARE(n)	(0x0c + (n) * 4)
+#define MAX_TIMER	3
+#define DEFAULT_TIMER	3
+
+struct bcm2835_timer {
+	void __iomem *control;
+	void __iomem *compare;
+	int match_mask;
+	struct clock_event_device evt;
+	struct irqaction act;
+};
+
+static void __iomem *system_clock __read_mostly;
+
+static u64 notrace bcm2835_sched_read(void)
+{
+	return readl_relaxed(system_clock);
+}
+
+static int bcm2835_time_set_next_event(unsigned long event,
+	struct clock_event_device *evt_dev)
+{
+	struct bcm2835_timer *timer = container_of(evt_dev,
+		struct bcm2835_timer, evt);
+	writel_relaxed(readl_relaxed(system_clock) + event,
+		timer->compare);
+	return 0;
+}
+
+static irqreturn_t bcm2835_time_interrupt(int irq, void *dev_id)
+{
+	struct bcm2835_timer *timer = dev_id;
+	void (*event_handler)(struct clock_event_device *);
+	if (readl_relaxed(timer->control) & timer->match_mask) {
+		writel_relaxed(timer->match_mask, timer->control);
+
+		event_handler = READ_ONCE(timer->evt.event_handler);
+		if (event_handler)
+			event_handler(&timer->evt);
+		return IRQ_HANDLED;
+	} else {
+		return IRQ_NONE;
+	}
+}
+
+static int __init bcm2835_timer_init(struct device_node *node)
+{
+	void __iomem *base;
+	u32 freq;
+	int irq, ret;
+	struct bcm2835_timer *timer;
+
+	base = of_iomap(node, 0);
+	if (!base) {
+		pr_err("Can't remap registers\n");
+		return -ENXIO;
+	}
+
+	ret = of_property_read_u32(node, "clock-frequency", &freq);
+	if (ret) {
+		pr_err("Can't read clock-frequency\n");
+		goto err_iounmap;
+	}
+
+	system_clock = base + REG_COUNTER_LO;
+	sched_clock_register(bcm2835_sched_read, 32, freq);
+
+	clocksource_mmio_init(base + REG_COUNTER_LO, node->name,
+		freq, 300, 32, clocksource_mmio_readl_up);
+
+	irq = irq_of_parse_and_map(node, DEFAULT_TIMER);
+	if (irq <= 0) {
+		pr_err("Can't parse IRQ\n");
+		ret = -EINVAL;
+		goto err_iounmap;
+	}
+
+	timer = kzalloc(sizeof(*timer), GFP_KERNEL);
+	if (!timer) {
+		ret = -ENOMEM;
+		goto err_iounmap;
+	}
+
+	timer->control = base + REG_CONTROL;
+	timer->compare = base + REG_COMPARE(DEFAULT_TIMER);
+	timer->match_mask = BIT(DEFAULT_TIMER);
+	timer->evt.name = node->name;
+	timer->evt.rating = 300;
+	timer->evt.features = CLOCK_EVT_FEAT_ONESHOT;
+	timer->evt.set_next_event = bcm2835_time_set_next_event;
+	timer->evt.cpumask = cpumask_of(0);
+	timer->act.name = node->name;
+	timer->act.flags = IRQF_TIMER | IRQF_SHARED;
+	timer->act.dev_id = timer;
+	timer->act.handler = bcm2835_time_interrupt;
+
+	ret = setup_irq(irq, &timer->act);
+	if (ret) {
+		pr_err("Can't set up timer IRQ\n");
+		goto err_timer_free;
+	}
+
+	clockevents_config_and_register(&timer->evt, freq, 0xf, 0xffffffff);
+
+	pr_info("bcm2835: system timer (irq = %d)\n", irq);
+
+	return 0;
+
+err_timer_free:
+	kfree(timer);
+
+err_iounmap:
+	iounmap(base);
+	return ret;
+}
+TIMER_OF_DECLARE(bcm2835, "brcm,bcm2835-system-timer",
+			bcm2835_timer_init);

drivers/clocksource/bcm_kona_timer.c

@@ -0,0 +1,206 @@
+/*
+ * Copyright (C) 2012 Broadcom Corporation
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/jiffies.h>
+#include <linux/clockchips.h>
+#include <linux/types.h>
+#include <linux/clk.h>
+
+#include <linux/io.h>
+
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+
+#define KONA_GPTIMER_STCS_OFFSET			0x00000000
+#define KONA_GPTIMER_STCLO_OFFSET			0x00000004
+#define KONA_GPTIMER_STCHI_OFFSET			0x00000008
+#define KONA_GPTIMER_STCM0_OFFSET			0x0000000C
+
+#define KONA_GPTIMER_STCS_TIMER_MATCH_SHIFT		0
+#define KONA_GPTIMER_STCS_COMPARE_ENABLE_SHIFT		4
+
+struct kona_bcm_timers {
+	int tmr_irq;
+	void __iomem *tmr_regs;
+};
+
+static struct kona_bcm_timers timers;
+
+static u32 arch_timer_rate;
+
+/*
+ * We use the peripheral timers for system tick, the cpu global timer for
+ * profile tick
+ */
+static void kona_timer_disable_and_clear(void __iomem *base)
+{
+	uint32_t reg;
+
+	/*
+	 * clear and disable interrupts
+	 * We are using compare/match register 0 for our system interrupts
+	 */
+	reg = readl(base + KONA_GPTIMER_STCS_OFFSET);
+
+	/* Clear compare (0) interrupt */
+	reg |= 1 << KONA_GPTIMER_STCS_TIMER_MATCH_SHIFT;
+	/* disable compare */
+	reg &= ~(1 << KONA_GPTIMER_STCS_COMPARE_ENABLE_SHIFT);
+
+	writel(reg, base + KONA_GPTIMER_STCS_OFFSET);
+
+}
+
+static int
+kona_timer_get_counter(void __iomem *timer_base, uint32_t *msw, uint32_t *lsw)
+{
+	int loop_limit = 3;
+
+	/*
+	 * Read 64-bit free running counter
+	 * 1. Read hi-word
+	 * 2. Read low-word
+	 * 3. Read hi-word again
+	 * 4.1
+	 *      if new hi-word is not equal to previously read hi-word, then
+	 *      start from #1
+	 * 4.2
+	 *      if new hi-word is equal to previously read hi-word then stop.
+	 */
+
+	do {
+		*msw = readl(timer_base + KONA_GPTIMER_STCHI_OFFSET);
+		*lsw = readl(timer_base + KONA_GPTIMER_STCLO_OFFSET);
+		if (*msw == readl(timer_base + KONA_GPTIMER_STCHI_OFFSET))
+			break;
+	} while (--loop_limit);
+	if (!loop_limit) {
+		pr_err("bcm_kona_timer: getting counter failed.\n");
+		pr_err(" Timer will be impacted\n");
+		return -ETIMEDOUT;
+	}
+
+	return 0;
+}
+
+static int kona_timer_set_next_event(unsigned long clc,
+				  struct clock_event_device *unused)
+{
+	/*
+	 * timer (0) is disabled by the timer interrupt already
+	 * so, here we reload the next event value and re-enable
+	 * the timer.
+	 *
+	 * This way, we are potentially losing the time between
+	 * timer-interrupt->set_next_event. CPU local timers, when
+	 * they come in should get rid of skew.
+	 */
+
+	uint32_t lsw, msw;
+	uint32_t reg;
+	int ret;
+
+	ret = kona_timer_get_counter(timers.tmr_regs, &msw, &lsw);
+	if (ret)
+		return ret;
+
+	/* Load the "next" event tick value */
+	writel(lsw + clc, timers.tmr_regs + KONA_GPTIMER_STCM0_OFFSET);
+
+	/* Enable compare */
+	reg = readl(timers.tmr_regs + KONA_GPTIMER_STCS_OFFSET);
+	reg |= (1 << KONA_GPTIMER_STCS_COMPARE_ENABLE_SHIFT);
+	writel(reg, timers.tmr_regs + KONA_GPTIMER_STCS_OFFSET);
+
+	return 0;
+}
+
+static int kona_timer_shutdown(struct clock_event_device *evt)
+{
+	kona_timer_disable_and_clear(timers.tmr_regs);
+	return 0;
+}
+
+static struct clock_event_device kona_clockevent_timer = {
+	.name = "timer 1",
+	.features = CLOCK_EVT_FEAT_ONESHOT,
+	.set_next_event = kona_timer_set_next_event,
+	.set_state_shutdown = kona_timer_shutdown,
+	.tick_resume = kona_timer_shutdown,
+};
+
+static void __init kona_timer_clockevents_init(void)
+{
+	kona_clockevent_timer.cpumask = cpumask_of(0);
+	clockevents_config_and_register(&kona_clockevent_timer,
+		arch_timer_rate, 6, 0xffffffff);
+}
+
+static irqreturn_t kona_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = &kona_clockevent_timer;
+
+	kona_timer_disable_and_clear(timers.tmr_regs);
+	evt->event_handler(evt);
+	return IRQ_HANDLED;
+}
+
+static struct irqaction kona_timer_irq = {
+	.name = "Kona Timer Tick",
+	.flags = IRQF_TIMER,
+	.handler = kona_timer_interrupt,
+};
+
+static int __init kona_timer_init(struct device_node *node)
+{
+	u32 freq;
+	struct clk *external_clk;
+
+	external_clk = of_clk_get_by_name(node, NULL);
+
+	if (!IS_ERR(external_clk)) {
+		arch_timer_rate = clk_get_rate(external_clk);
+		clk_prepare_enable(external_clk);
+	} else if (!of_property_read_u32(node, "clock-frequency", &freq)) {
+		arch_timer_rate = freq;
+	} else {
+		pr_err("Kona Timer v1 unable to determine clock-frequency\n");
+		return -EINVAL;
+	}
+
+	/* Setup IRQ numbers */
+	timers.tmr_irq = irq_of_parse_and_map(node, 0);
+
+	/* Setup IO addresses */
+	timers.tmr_regs = of_iomap(node, 0);
+
+	kona_timer_disable_and_clear(timers.tmr_regs);
+
+	kona_timer_clockevents_init();
+	setup_irq(timers.tmr_irq, &kona_timer_irq);
+	kona_timer_set_next_event((arch_timer_rate / HZ), NULL);
+
+	return 0;
+}
+
+TIMER_OF_DECLARE(brcm_kona, "brcm,kona-timer", kona_timer_init);
+/*
+ * bcm,kona-timer is deprecated by brcm,kona-timer
+ * being kept here for driver compatibility
+ */
+TIMER_OF_DECLARE(bcm_kona, "bcm,kona-timer", kona_timer_init);

drivers/clocksource/cadence_ttc_timer.c

@@ -0,0 +1,543 @@
+/*
+ * This file contains driver for the Cadence Triple Timer Counter Rev 06
+ *
+ *  Copyright (C) 2011-2013 Xilinx
+ *
+ * based on arch/mips/kernel/time.c timer driver
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/slab.h>
+#include <linux/sched_clock.h>
+
+/*
+ * This driver configures the 2 16/32-bit count-up timers as follows:
+ *
+ * T1: Timer 1, clocksource for generic timekeeping
+ * T2: Timer 2, clockevent source for hrtimers
+ * T3: Timer 3, <unused>
+ *
+ * The input frequency to the timer module for emulation is 2.5MHz which is
+ * common to all the timer channels (T1, T2, and T3). With a pre-scaler of 32,
+ * the timers are clocked at 78.125KHz (12.8 us resolution).
+
+ * The input frequency to the timer module in silicon is configurable and
+ * obtained from device tree. The pre-scaler of 32 is used.
+ */
+
+/*
+ * Timer Register Offset Definitions of Timer 1, Increment base address by 4
+ * and use same offsets for Timer 2
+ */
+#define TTC_CLK_CNTRL_OFFSET		0x00 /* Clock Control Reg, RW */
+#define TTC_CNT_CNTRL_OFFSET		0x0C /* Counter Control Reg, RW */
+#define TTC_COUNT_VAL_OFFSET		0x18 /* Counter Value Reg, RO */
+#define TTC_INTR_VAL_OFFSET		0x24 /* Interval Count Reg, RW */
+#define TTC_ISR_OFFSET		0x54 /* Interrupt Status Reg, RO */
+#define TTC_IER_OFFSET		0x60 /* Interrupt Enable Reg, RW */
+
+#define TTC_CNT_CNTRL_DISABLE_MASK	0x1
+
+#define TTC_CLK_CNTRL_CSRC_MASK		(1 << 5)	/* clock source */
+#define TTC_CLK_CNTRL_PSV_MASK		0x1e
+#define TTC_CLK_CNTRL_PSV_SHIFT		1
+
+/*
+ * Setup the timers to use pre-scaling, using a fixed value for now that will
+ * work across most input frequency, but it may need to be more dynamic
+ */
+#define PRESCALE_EXPONENT	11	/* 2 ^ PRESCALE_EXPONENT = PRESCALE */
+#define PRESCALE		2048	/* The exponent must match this */
+#define CLK_CNTRL_PRESCALE	((PRESCALE_EXPONENT - 1) << 1)
+#define CLK_CNTRL_PRESCALE_EN	1
+#define CNT_CNTRL_RESET		(1 << 4)
+
+#define MAX_F_ERR 50
+
+/**
+ * struct ttc_timer - This definition defines local timer structure
+ *
+ * @base_addr:	Base address of timer
+ * @freq:	Timer input clock frequency
+ * @clk:	Associated clock source
+ * @clk_rate_change_nb	Notifier block for clock rate changes
+ */
+struct ttc_timer {
+	void __iomem *base_addr;
+	unsigned long freq;
+	struct clk *clk;
+	struct notifier_block clk_rate_change_nb;
+};
+
+#define to_ttc_timer(x) \
+		container_of(x, struct ttc_timer, clk_rate_change_nb)
+
+struct ttc_timer_clocksource {
+	u32			scale_clk_ctrl_reg_old;
+	u32			scale_clk_ctrl_reg_new;
+	struct ttc_timer	ttc;
+	struct clocksource	cs;
+};
+
+#define to_ttc_timer_clksrc(x) \
+		container_of(x, struct ttc_timer_clocksource, cs)
+
+struct ttc_timer_clockevent {
+	struct ttc_timer		ttc;
+	struct clock_event_device	ce;
+};
+
+#define to_ttc_timer_clkevent(x) \
+		container_of(x, struct ttc_timer_clockevent, ce)
+
+static void __iomem *ttc_sched_clock_val_reg;
+
+/**
+ * ttc_set_interval - Set the timer interval value
+ *
+ * @timer:	Pointer to the timer instance
+ * @cycles:	Timer interval ticks
+ **/
+static void ttc_set_interval(struct ttc_timer *timer,
+					unsigned long cycles)
+{
+	u32 ctrl_reg;
+
+	/* Disable the counter, set the counter value  and re-enable counter */
+	ctrl_reg = readl_relaxed(timer->base_addr + TTC_CNT_CNTRL_OFFSET);
+	ctrl_reg |= TTC_CNT_CNTRL_DISABLE_MASK;
+	writel_relaxed(ctrl_reg, timer->base_addr + TTC_CNT_CNTRL_OFFSET);
+
+	writel_relaxed(cycles, timer->base_addr + TTC_INTR_VAL_OFFSET);
+
+	/*
+	 * Reset the counter (0x10) so that it starts from 0, one-shot
+	 * mode makes this needed for timing to be right.
+	 */
+	ctrl_reg |= CNT_CNTRL_RESET;
+	ctrl_reg &= ~TTC_CNT_CNTRL_DISABLE_MASK;
+	writel_relaxed(ctrl_reg, timer->base_addr + TTC_CNT_CNTRL_OFFSET);
+}
+
+/**
+ * ttc_clock_event_interrupt - Clock event timer interrupt handler
+ *
+ * @irq:	IRQ number of the Timer
+ * @dev_id:	void pointer to the ttc_timer instance
+ *
+ * returns: Always IRQ_HANDLED - success
+ **/
+static irqreturn_t ttc_clock_event_interrupt(int irq, void *dev_id)
+{
+	struct ttc_timer_clockevent *ttce = dev_id;
+	struct ttc_timer *timer = &ttce->ttc;
+
+	/* Acknowledge the interrupt and call event handler */
+	readl_relaxed(timer->base_addr + TTC_ISR_OFFSET);
+
+	ttce->ce.event_handler(&ttce->ce);
+
+	return IRQ_HANDLED;
+}
+
+/**
+ * __ttc_clocksource_read - Reads the timer counter register
+ *
+ * returns: Current timer counter register value
+ **/
+static u64 __ttc_clocksource_read(struct clocksource *cs)
+{
+	struct ttc_timer *timer = &to_ttc_timer_clksrc(cs)->ttc;
+
+	return (u64)readl_relaxed(timer->base_addr +
+				TTC_COUNT_VAL_OFFSET);
+}
+
+static u64 notrace ttc_sched_clock_read(void)
+{
+	return readl_relaxed(ttc_sched_clock_val_reg);
+}
+
+/**
+ * ttc_set_next_event - Sets the time interval for next event
+ *
+ * @cycles:	Timer interval ticks
+ * @evt:	Address of clock event instance
+ *
+ * returns: Always 0 - success
+ **/
+static int ttc_set_next_event(unsigned long cycles,
+					struct clock_event_device *evt)
+{
+	struct ttc_timer_clockevent *ttce = to_ttc_timer_clkevent(evt);
+	struct ttc_timer *timer = &ttce->ttc;
+
+	ttc_set_interval(timer, cycles);
+	return 0;
+}
+
+/**
+ * ttc_set_{shutdown|oneshot|periodic} - Sets the state of timer
+ *
+ * @evt:	Address of clock event instance
+ **/
+static int ttc_shutdown(struct clock_event_device *evt)
+{
+	struct ttc_timer_clockevent *ttce = to_ttc_timer_clkevent(evt);
+	struct ttc_timer *timer = &ttce->ttc;
+	u32 ctrl_reg;
+
+	ctrl_reg = readl_relaxed(timer->base_addr + TTC_CNT_CNTRL_OFFSET);
+	ctrl_reg |= TTC_CNT_CNTRL_DISABLE_MASK;
+	writel_relaxed(ctrl_reg, timer->base_addr + TTC_CNT_CNTRL_OFFSET);
+	return 0;
+}
+
+static int ttc_set_periodic(struct clock_event_device *evt)
+{
+	struct ttc_timer_clockevent *ttce = to_ttc_timer_clkevent(evt);
+	struct ttc_timer *timer = &ttce->ttc;
+
+	ttc_set_interval(timer,
+			 DIV_ROUND_CLOSEST(ttce->ttc.freq, PRESCALE * HZ));
+	return 0;
+}
+
+static int ttc_resume(struct clock_event_device *evt)
+{
+	struct ttc_timer_clockevent *ttce = to_ttc_timer_clkevent(evt);
+	struct ttc_timer *timer = &ttce->ttc;
+	u32 ctrl_reg;
+
+	ctrl_reg = readl_relaxed(timer->base_addr + TTC_CNT_CNTRL_OFFSET);
+	ctrl_reg &= ~TTC_CNT_CNTRL_DISABLE_MASK;
+	writel_relaxed(ctrl_reg, timer->base_addr + TTC_CNT_CNTRL_OFFSET);
+	return 0;
+}
+
+static int ttc_rate_change_clocksource_cb(struct notifier_block *nb,
+		unsigned long event, void *data)
+{
+	struct clk_notifier_data *ndata = data;
+	struct ttc_timer *ttc = to_ttc_timer(nb);
+	struct ttc_timer_clocksource *ttccs = container_of(ttc,
+			struct ttc_timer_clocksource, ttc);
+
+	switch (event) {
+	case PRE_RATE_CHANGE:
+	{
+		u32 psv;
+		unsigned long factor, rate_low, rate_high;
+
+		if (ndata->new_rate > ndata->old_rate) {
+			factor = DIV_ROUND_CLOSEST(ndata->new_rate,
+					ndata->old_rate);
+			rate_low = ndata->old_rate;
+			rate_high = ndata->new_rate;
+		} else {
+			factor = DIV_ROUND_CLOSEST(ndata->old_rate,
+					ndata->new_rate);
+			rate_low = ndata->new_rate;
+			rate_high = ndata->old_rate;
+		}
+
+		if (!is_power_of_2(factor))
+				return NOTIFY_BAD;
+
+		if (abs(rate_high - (factor * rate_low)) > MAX_F_ERR)
+			return NOTIFY_BAD;
+
+		factor = __ilog2_u32(factor);
+
+		/*
+		 * store timer clock ctrl register so we can restore it in case
+		 * of an abort.
+		 */
+		ttccs->scale_clk_ctrl_reg_old =
+			readl_relaxed(ttccs->ttc.base_addr +
+			TTC_CLK_CNTRL_OFFSET);
+
+		psv = (ttccs->scale_clk_ctrl_reg_old &
+				TTC_CLK_CNTRL_PSV_MASK) >>
+				TTC_CLK_CNTRL_PSV_SHIFT;
+		if (ndata->new_rate < ndata->old_rate)
+			psv -= factor;
+		else
+			psv += factor;
+
+		/* prescaler within legal range? */
+		if (psv & ~(TTC_CLK_CNTRL_PSV_MASK >> TTC_CLK_CNTRL_PSV_SHIFT))
+			return NOTIFY_BAD;
+
+		ttccs->scale_clk_ctrl_reg_new = ttccs->scale_clk_ctrl_reg_old &
+			~TTC_CLK_CNTRL_PSV_MASK;
+		ttccs->scale_clk_ctrl_reg_new |= psv << TTC_CLK_CNTRL_PSV_SHIFT;
+
+
+		/* scale down: adjust divider in post-change notification */
+		if (ndata->new_rate < ndata->old_rate)
+			return NOTIFY_DONE;
+
+		/* scale up: adjust divider now - before frequency change */
+		writel_relaxed(ttccs->scale_clk_ctrl_reg_new,
+			       ttccs->ttc.base_addr + TTC_CLK_CNTRL_OFFSET);
+		break;
+	}
+	case POST_RATE_CHANGE:
+		/* scale up: pre-change notification did the adjustment */
+		if (ndata->new_rate > ndata->old_rate)
+			return NOTIFY_OK;
+
+		/* scale down: adjust divider now - after frequency change */
+		writel_relaxed(ttccs->scale_clk_ctrl_reg_new,
+			       ttccs->ttc.base_addr + TTC_CLK_CNTRL_OFFSET);
+		break;
+
+	case ABORT_RATE_CHANGE:
+		/* we have to undo the adjustment in case we scale up */
+		if (ndata->new_rate < ndata->old_rate)
+			return NOTIFY_OK;
+
+		/* restore original register value */
+		writel_relaxed(ttccs->scale_clk_ctrl_reg_old,
+			       ttccs->ttc.base_addr + TTC_CLK_CNTRL_OFFSET);
+		/* fall through */
+	default:
+		return NOTIFY_DONE;
+	}
+
+	return NOTIFY_DONE;
+}
+
+static int __init ttc_setup_clocksource(struct clk *clk, void __iomem *base,
+					 u32 timer_width)
+{
+	struct ttc_timer_clocksource *ttccs;
+	int err;
+
+	ttccs = kzalloc(sizeof(*ttccs), GFP_KERNEL);
+	if (!ttccs)
+		return -ENOMEM;
+
+	ttccs->ttc.clk = clk;
+
+	err = clk_prepare_enable(ttccs->ttc.clk);
+	if (err) {
+		kfree(ttccs);
+		return err;
+	}
+
+	ttccs->ttc.freq = clk_get_rate(ttccs->ttc.clk);
+
+	ttccs->ttc.clk_rate_change_nb.notifier_call =
+		ttc_rate_change_clocksource_cb;
+	ttccs->ttc.clk_rate_change_nb.next = NULL;
+
+	err = clk_notifier_register(ttccs->ttc.clk,
+				    &ttccs->ttc.clk_rate_change_nb);
+	if (err)
+		pr_warn("Unable to register clock notifier.\n");
+
+	ttccs->ttc.base_addr = base;
+	ttccs->cs.name = "ttc_clocksource";
+	ttccs->cs.rating = 200;
+	ttccs->cs.read = __ttc_clocksource_read;
+	ttccs->cs.mask = CLOCKSOURCE_MASK(timer_width);
+	ttccs->cs.flags = CLOCK_SOURCE_IS_CONTINUOUS;
+
+	/*
+	 * Setup the clock source counter to be an incrementing counter
+	 * with no interrupt and it rolls over at 0xFFFF. Pre-scale
+	 * it by 32 also. Let it start running now.
+	 */
+	writel_relaxed(0x0,  ttccs->ttc.base_addr + TTC_IER_OFFSET);
+	writel_relaxed(CLK_CNTRL_PRESCALE | CLK_CNTRL_PRESCALE_EN,
+		     ttccs->ttc.base_addr + TTC_CLK_CNTRL_OFFSET);
+	writel_relaxed(CNT_CNTRL_RESET,
+		     ttccs->ttc.base_addr + TTC_CNT_CNTRL_OFFSET);
+
+	err = clocksource_register_hz(&ttccs->cs, ttccs->ttc.freq / PRESCALE);
+	if (err) {
+		kfree(ttccs);
+		return err;
+	}
+
+	ttc_sched_clock_val_reg = base + TTC_COUNT_VAL_OFFSET;
+	sched_clock_register(ttc_sched_clock_read, timer_width,
+			     ttccs->ttc.freq / PRESCALE);
+
+	return 0;
+}
+
+static int ttc_rate_change_clockevent_cb(struct notifier_block *nb,
+		unsigned long event, void *data)
+{
+	struct clk_notifier_data *ndata = data;
+	struct ttc_timer *ttc = to_ttc_timer(nb);
+	struct ttc_timer_clockevent *ttcce = container_of(ttc,
+			struct ttc_timer_clockevent, ttc);
+
+	switch (event) {
+	case POST_RATE_CHANGE:
+		/* update cached frequency */
+		ttc->freq = ndata->new_rate;
+
+		clockevents_update_freq(&ttcce->ce, ndata->new_rate / PRESCALE);
+
+		/* fall through */
+	case PRE_RATE_CHANGE:
+	case ABORT_RATE_CHANGE:
+	default:
+		return NOTIFY_DONE;
+	}
+}
+
+static int __init ttc_setup_clockevent(struct clk *clk,
+				       void __iomem *base, u32 irq)
+{
+	struct ttc_timer_clockevent *ttcce;
+	int err;
+
+	ttcce = kzalloc(sizeof(*ttcce), GFP_KERNEL);
+	if (!ttcce)
+		return -ENOMEM;
+
+	ttcce->ttc.clk = clk;
+
+	err = clk_prepare_enable(ttcce->ttc.clk);
+	if (err)
+		goto out_kfree;
+
+	ttcce->ttc.clk_rate_change_nb.notifier_call =
+		ttc_rate_change_clockevent_cb;
+	ttcce->ttc.clk_rate_change_nb.next = NULL;
+
+	err = clk_notifier_register(ttcce->ttc.clk,
+				    &ttcce->ttc.clk_rate_change_nb);
+	if (err) {
+		pr_warn("Unable to register clock notifier.\n");
+		goto out_kfree;
+	}
+
+	ttcce->ttc.freq = clk_get_rate(ttcce->ttc.clk);
+
+	ttcce->ttc.base_addr = base;
+	ttcce->ce.name = "ttc_clockevent";
+	ttcce->ce.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
+	ttcce->ce.set_next_event = ttc_set_next_event;
+	ttcce->ce.set_state_shutdown = ttc_shutdown;
+	ttcce->ce.set_state_periodic = ttc_set_periodic;
+	ttcce->ce.set_state_oneshot = ttc_shutdown;
+	ttcce->ce.tick_resume = ttc_resume;
+	ttcce->ce.rating = 200;
+	ttcce->ce.irq = irq;
+	ttcce->ce.cpumask = cpu_possible_mask;
+
+	/*
+	 * Setup the clock event timer to be an interval timer which
+	 * is prescaled by 32 using the interval interrupt. Leave it
+	 * disabled for now.
+	 */
+	writel_relaxed(0x23, ttcce->ttc.base_addr + TTC_CNT_CNTRL_OFFSET);
+	writel_relaxed(CLK_CNTRL_PRESCALE | CLK_CNTRL_PRESCALE_EN,
+		     ttcce->ttc.base_addr + TTC_CLK_CNTRL_OFFSET);
+	writel_relaxed(0x1,  ttcce->ttc.base_addr + TTC_IER_OFFSET);
+
+	err = request_irq(irq, ttc_clock_event_interrupt,
+			  IRQF_TIMER, ttcce->ce.name, ttcce);
+	if (err)
+		goto out_kfree;
+
+	clockevents_config_and_register(&ttcce->ce,
+			ttcce->ttc.freq / PRESCALE, 1, 0xfffe);
+
+	return 0;
+
+out_kfree:
+	kfree(ttcce);
+	return err;
+}
+
+/**
+ * ttc_timer_init - Initialize the timer
+ *
+ * Initializes the timer hardware and register the clock source and clock event
+ * timers with Linux kernal timer framework
+ */
+static int __init ttc_timer_init(struct device_node *timer)
+{
+	unsigned int irq;
+	void __iomem *timer_baseaddr;
+	struct clk *clk_cs, *clk_ce;
+	static int initialized;
+	int clksel, ret;
+	u32 timer_width = 16;
+
+	if (initialized)
+		return 0;
+
+	initialized = 1;
+
+	/*
+	 * Get the 1st Triple Timer Counter (TTC) block from the device tree
+	 * and use it. Note that the event timer uses the interrupt and it's the
+	 * 2nd TTC hence the irq_of_parse_and_map(,1)
+	 */
+	timer_baseaddr = of_iomap(timer, 0);
+	if (!timer_baseaddr) {
+		pr_err("ERROR: invalid timer base address\n");
+		return -ENXIO;
+	}
+
+	irq = irq_of_parse_and_map(timer, 1);
+	if (irq <= 0) {
+		pr_err("ERROR: invalid interrupt number\n");
+		return -EINVAL;
+	}
+
+	of_property_read_u32(timer, "timer-width", &timer_width);
+
+	clksel = readl_relaxed(timer_baseaddr + TTC_CLK_CNTRL_OFFSET);
+	clksel = !!(clksel & TTC_CLK_CNTRL_CSRC_MASK);
+	clk_cs = of_clk_get(timer, clksel);
+	if (IS_ERR(clk_cs)) {
+		pr_err("ERROR: timer input clock not found\n");
+		return PTR_ERR(clk_cs);
+	}
+
+	clksel = readl_relaxed(timer_baseaddr + 4 + TTC_CLK_CNTRL_OFFSET);
+	clksel = !!(clksel & TTC_CLK_CNTRL_CSRC_MASK);
+	clk_ce = of_clk_get(timer, clksel);
+	if (IS_ERR(clk_ce)) {
+		pr_err("ERROR: timer input clock not found\n");
+		return PTR_ERR(clk_ce);
+	}
+
+	ret = ttc_setup_clocksource(clk_cs, timer_baseaddr, timer_width);
+	if (ret)
+		return ret;
+
+	ret = ttc_setup_clockevent(clk_ce, timer_baseaddr + 4, irq);
+	if (ret)
+		return ret;
+
+	pr_info("%s #0 at %p, irq=%d\n", timer->name, timer_baseaddr, irq);
+
+	return 0;
+}
+
+TIMER_OF_DECLARE(ttc, "cdns,ttc", ttc_timer_init);

drivers/clocksource/clksrc-dbx500-prcmu.c

@@ -0,0 +1,90 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2011
+ *
+ * License Terms: GNU General Public License v2
+ * Author: Mattias Wallin <mattias.wallin@stericsson.com> for ST-Ericsson
+ * Author: Sundar Iyer for ST-Ericsson
+ * sched_clock implementation is based on:
+ * plat-nomadik/timer.c Linus Walleij <linus.walleij@stericsson.com>
+ *
+ * DBx500-PRCMU Timer
+ * The PRCMU has 5 timers which are available in a always-on
+ * power domain.  We use the Timer 4 for our always-on clock
+ * source on DB8500.
+ */
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/clockchips.h>
+#include <linux/sched_clock.h>
+
+#define RATE_32K		32768
+
+#define TIMER_MODE_CONTINOUS	0x1
+#define TIMER_DOWNCOUNT_VAL	0xffffffff
+
+#define PRCMU_TIMER_REF		0
+#define PRCMU_TIMER_DOWNCOUNT	0x4
+#define PRCMU_TIMER_MODE	0x8
+
+#define SCHED_CLOCK_MIN_WRAP 131072 /* 2^32 / 32768 */
+
+static void __iomem *clksrc_dbx500_timer_base;
+
+static u64 notrace clksrc_dbx500_prcmu_read(struct clocksource *cs)
+{
+	void __iomem *base = clksrc_dbx500_timer_base;
+	u32 count, count2;
+
+	do {
+		count = readl_relaxed(base + PRCMU_TIMER_DOWNCOUNT);
+		count2 = readl_relaxed(base + PRCMU_TIMER_DOWNCOUNT);
+	} while (count2 != count);
+
+	/* Negate because the timer is a decrementing counter */
+	return ~count;
+}
+
+static struct clocksource clocksource_dbx500_prcmu = {
+	.name		= "dbx500-prcmu-timer",
+	.rating		= 300,
+	.read		= clksrc_dbx500_prcmu_read,
+	.mask		= CLOCKSOURCE_MASK(32),
+	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+#ifdef CONFIG_CLKSRC_DBX500_PRCMU_SCHED_CLOCK
+
+static u64 notrace dbx500_prcmu_sched_clock_read(void)
+{
+	if (unlikely(!clksrc_dbx500_timer_base))
+		return 0;
+
+	return clksrc_dbx500_prcmu_read(&clocksource_dbx500_prcmu);
+}
+
+#endif
+
+static int __init clksrc_dbx500_prcmu_init(struct device_node *node)
+{
+	clksrc_dbx500_timer_base = of_iomap(node, 0);
+
+	/*
+	 * The A9 sub system expects the timer to be configured as
+	 * a continous looping timer.
+	 * The PRCMU should configure it but if it for some reason
+	 * don't we do it here.
+	 */
+	if (readl(clksrc_dbx500_timer_base + PRCMU_TIMER_MODE) !=
+	    TIMER_MODE_CONTINOUS) {
+		writel(TIMER_MODE_CONTINOUS,
+		       clksrc_dbx500_timer_base + PRCMU_TIMER_MODE);
+		writel(TIMER_DOWNCOUNT_VAL,
+		       clksrc_dbx500_timer_base + PRCMU_TIMER_REF);
+	}
+#ifdef CONFIG_CLKSRC_DBX500_PRCMU_SCHED_CLOCK
+	sched_clock_register(dbx500_prcmu_sched_clock_read, 32, RATE_32K);
+#endif
+	return clocksource_register_hz(&clocksource_dbx500_prcmu, RATE_32K);
+}
+TIMER_OF_DECLARE(dbx500_prcmu, "stericsson,db8500-prcmu-timer-4",
+		       clksrc_dbx500_prcmu_init);

drivers/clocksource/clksrc_st_lpc.c

@@ -0,0 +1,135 @@
+/*
+ * Clocksource using the Low Power Timer found in the Low Power Controller (LPC)
+ *
+ * Copyright (C) 2015 STMicroelectronics – All Rights Reserved
+ *
+ * Author(s): Francesco Virlinzi <francesco.virlinzi@st.com>
+ *	      Ajit Pal Singh <ajitpal.singh@st.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/clk.h>
+#include <linux/clocksource.h>
+#include <linux/init.h>
+#include <linux/of_address.h>
+#include <linux/sched_clock.h>
+#include <linux/slab.h>
+
+#include <dt-bindings/mfd/st-lpc.h>
+
+/* Low Power Timer */
+#define LPC_LPT_LSB_OFF		0x400
+#define LPC_LPT_MSB_OFF		0x404
+#define LPC_LPT_START_OFF	0x408
+
+static struct st_clksrc_ddata {
+	struct clk		*clk;
+	void __iomem		*base;
+} ddata;
+
+static void __init st_clksrc_reset(void)
+{
+	writel_relaxed(0, ddata.base + LPC_LPT_START_OFF);
+	writel_relaxed(0, ddata.base + LPC_LPT_MSB_OFF);
+	writel_relaxed(0, ddata.base + LPC_LPT_LSB_OFF);
+	writel_relaxed(1, ddata.base + LPC_LPT_START_OFF);
+}
+
+static u64 notrace st_clksrc_sched_clock_read(void)
+{
+	return (u64)readl_relaxed(ddata.base + LPC_LPT_LSB_OFF);
+}
+
+static int __init st_clksrc_init(void)
+{
+	unsigned long rate;
+	int ret;
+
+	st_clksrc_reset();
+
+	rate = clk_get_rate(ddata.clk);
+
+	sched_clock_register(st_clksrc_sched_clock_read, 32, rate);
+
+	ret = clocksource_mmio_init(ddata.base + LPC_LPT_LSB_OFF,
+				    "clksrc-st-lpc", rate, 300, 32,
+				    clocksource_mmio_readl_up);
+	if (ret) {
+		pr_err("clksrc-st-lpc: Failed to register clocksource\n");
+		return ret;
+	}
+
+	return 0;
+}
+
+static int __init st_clksrc_setup_clk(struct device_node *np)
+{
+	struct clk *clk;
+
+	clk = of_clk_get(np, 0);
+	if (IS_ERR(clk)) {
+		pr_err("clksrc-st-lpc: Failed to get LPC clock\n");
+		return PTR_ERR(clk);
+	}
+
+	if (clk_prepare_enable(clk)) {
+		pr_err("clksrc-st-lpc: Failed to enable LPC clock\n");
+		return -EINVAL;
+	}
+
+	if (!clk_get_rate(clk)) {
+		pr_err("clksrc-st-lpc: Failed to get LPC clock rate\n");
+		clk_disable_unprepare(clk);
+		return -EINVAL;
+	}
+
+	ddata.clk = clk;
+
+	return 0;
+}
+
+static int __init st_clksrc_of_register(struct device_node *np)
+{
+	int ret;
+	uint32_t mode;
+
+	ret = of_property_read_u32(np, "st,lpc-mode", &mode);
+	if (ret) {
+		pr_err("clksrc-st-lpc: An LPC mode must be provided\n");
+		return ret;
+	}
+
+	/* LPC can either run as a Clocksource or in RTC or WDT mode */
+	if (mode != ST_LPC_MODE_CLKSRC)
+		return 0;
+
+	ddata.base = of_iomap(np, 0);
+	if (!ddata.base) {
+		pr_err("clksrc-st-lpc: Unable to map iomem\n");
+		return -ENXIO;
+	}
+
+	ret = st_clksrc_setup_clk(np);
+	if (ret) {
+		iounmap(ddata.base);
+		return ret;
+	}
+
+	ret = st_clksrc_init();
+	if (ret) {
+		clk_disable_unprepare(ddata.clk);
+		clk_put(ddata.clk);
+		iounmap(ddata.base);
+		return ret;
+	}
+
+	pr_info("clksrc-st-lpc: clocksource initialised - running @ %luHz\n",
+		clk_get_rate(ddata.clk));
+
+	return ret;
+}
+TIMER_OF_DECLARE(ddata, "st,stih407-lpc", st_clksrc_of_register);

drivers/clocksource/clps711x-timer.c

@@ -0,0 +1,123 @@
+/*
+ *  Cirrus Logic CLPS711X clocksource driver
+ *
+ *  Copyright (C) 2014 Alexander Shiyan <shc_work@mail.ru>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+#include <linux/slab.h>
+
+enum {
+	CLPS711X_CLKSRC_CLOCKSOURCE,
+	CLPS711X_CLKSRC_CLOCKEVENT,
+};
+
+static void __iomem *tcd;
+
+static u64 notrace clps711x_sched_clock_read(void)
+{
+	return ~readw(tcd);
+}
+
+static int __init _clps711x_clksrc_init(struct clk *clock, void __iomem *base)
+{
+	unsigned long rate;
+
+	if (!base)
+		return -ENOMEM;
+	if (IS_ERR(clock))
+		return PTR_ERR(clock);
+
+	rate = clk_get_rate(clock);
+
+	tcd = base;
+
+	clocksource_mmio_init(tcd, "clps711x-clocksource", rate, 300, 16,
+			      clocksource_mmio_readw_down);
+
+	sched_clock_register(clps711x_sched_clock_read, 16, rate);
+
+	return 0;
+}
+
+static irqreturn_t clps711x_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static int __init _clps711x_clkevt_init(struct clk *clock, void __iomem *base,
+					unsigned int irq)
+{
+	struct clock_event_device *clkevt;
+	unsigned long rate;
+
+	if (!irq)
+		return -EINVAL;
+	if (!base)
+		return -ENOMEM;
+	if (IS_ERR(clock))
+		return PTR_ERR(clock);
+
+	clkevt = kzalloc(sizeof(*clkevt), GFP_KERNEL);
+	if (!clkevt)
+		return -ENOMEM;
+
+	rate = clk_get_rate(clock);
+
+	/* Set Timer prescaler */
+	writew(DIV_ROUND_CLOSEST(rate, HZ), base);
+
+	clkevt->name = "clps711x-clockevent";
+	clkevt->rating = 300;
+	clkevt->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_C3STOP;
+	clkevt->cpumask = cpumask_of(0);
+	clockevents_config_and_register(clkevt, HZ, 0, 0);
+
+	return request_irq(irq, clps711x_timer_interrupt, IRQF_TIMER,
+			   "clps711x-timer", clkevt);
+}
+
+void __init clps711x_clksrc_init(void __iomem *tc1_base, void __iomem *tc2_base,
+				 unsigned int irq)
+{
+	struct clk *tc1 = clk_get_sys("clps711x-timer.0", NULL);
+	struct clk *tc2 = clk_get_sys("clps711x-timer.1", NULL);
+
+	BUG_ON(_clps711x_clksrc_init(tc1, tc1_base));
+	BUG_ON(_clps711x_clkevt_init(tc2, tc2_base, irq));
+}
+
+#ifdef CONFIG_TIMER_OF
+static int __init clps711x_timer_init(struct device_node *np)
+{
+	unsigned int irq = irq_of_parse_and_map(np, 0);
+	struct clk *clock = of_clk_get(np, 0);
+	void __iomem *base = of_iomap(np, 0);
+
+	switch (of_alias_get_id(np, "timer")) {
+	case CLPS711X_CLKSRC_CLOCKSOURCE:
+		return _clps711x_clksrc_init(clock, base);
+	case CLPS711X_CLKSRC_CLOCKEVENT:
+		return _clps711x_clkevt_init(clock, base, irq);
+	default:
+		return -EINVAL;
+	}
+}
+TIMER_OF_DECLARE(clps711x, "cirrus,ep7209-timer", clps711x_timer_init);
+#endif

drivers/clocksource/cs5535-clockevt.c

@@ -0,0 +1,196 @@
+/*
+ * Clock event driver for the CS5535/CS5536
+ *
+ * Copyright (C) 2006, Advanced Micro Devices, Inc.
+ * Copyright (C) 2007  Andres Salomon <dilinger@debian.org>
+ * Copyright (C) 2009  Andres Salomon <dilinger@collabora.co.uk>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public License
+ * as published by the Free Software Foundation.
+ *
+ * The MFGPTs are documented in AMD Geode CS5536 Companion Device Data Book.
+ */
+
+#include <linux/kernel.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/cs5535.h>
+#include <linux/clockchips.h>
+
+#define DRV_NAME "cs5535-clockevt"
+
+static int timer_irq;
+module_param_hw_named(irq, timer_irq, int, irq, 0644);
+MODULE_PARM_DESC(irq, "Which IRQ to use for the clock source MFGPT ticks.");
+
+/*
+ * We are using the 32.768kHz input clock - it's the only one that has the
+ * ranges we find desirable.  The following table lists the suitable
+ * divisors and the associated Hz, minimum interval and the maximum interval:
+ *
+ *  Divisor   Hz      Min Delta (s)  Max Delta (s)
+ *   1        32768   .00048828125      2.000
+ *   2        16384   .0009765625       4.000
+ *   4         8192   .001953125        8.000
+ *   8         4096   .00390625        16.000
+ *   16        2048   .0078125         32.000
+ *   32        1024   .015625          64.000
+ *   64         512   .03125          128.000
+ *  128         256   .0625           256.000
+ *  256         128   .125            512.000
+ */
+
+static struct cs5535_mfgpt_timer *cs5535_event_clock;
+
+/* Selected from the table above */
+
+#define MFGPT_DIVISOR 16
+#define MFGPT_SCALE  4     /* divisor = 2^(scale) */
+#define MFGPT_HZ  (32768 / MFGPT_DIVISOR)
+#define MFGPT_PERIODIC (MFGPT_HZ / HZ)
+
+/*
+ * The MFGPT timers on the CS5536 provide us with suitable timers to use
+ * as clock event sources - not as good as a HPET or APIC, but certainly
+ * better than the PIT.  This isn't a general purpose MFGPT driver, but
+ * a simplified one designed specifically to act as a clock event source.
+ * For full details about the MFGPT, please consult the CS5536 data sheet.
+ */
+
+static void disable_timer(struct cs5535_mfgpt_timer *timer)
+{
+	/* avoid races by clearing CMP1 and CMP2 unconditionally */
+	cs5535_mfgpt_write(timer, MFGPT_REG_SETUP,
+			(uint16_t) ~MFGPT_SETUP_CNTEN | MFGPT_SETUP_CMP1 |
+				MFGPT_SETUP_CMP2);
+}
+
+static void start_timer(struct cs5535_mfgpt_timer *timer, uint16_t delta)
+{
+	cs5535_mfgpt_write(timer, MFGPT_REG_CMP2, delta);
+	cs5535_mfgpt_write(timer, MFGPT_REG_COUNTER, 0);
+
+	cs5535_mfgpt_write(timer, MFGPT_REG_SETUP,
+			MFGPT_SETUP_CNTEN | MFGPT_SETUP_CMP2);
+}
+
+static int mfgpt_shutdown(struct clock_event_device *evt)
+{
+	disable_timer(cs5535_event_clock);
+	return 0;
+}
+
+static int mfgpt_set_periodic(struct clock_event_device *evt)
+{
+	disable_timer(cs5535_event_clock);
+	start_timer(cs5535_event_clock, MFGPT_PERIODIC);
+	return 0;
+}
+
+static int mfgpt_next_event(unsigned long delta, struct clock_event_device *evt)
+{
+	start_timer(cs5535_event_clock, delta);
+	return 0;
+}
+
+static struct clock_event_device cs5535_clockevent = {
+	.name = DRV_NAME,
+	.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+	.set_state_shutdown = mfgpt_shutdown,
+	.set_state_periodic = mfgpt_set_periodic,
+	.set_state_oneshot = mfgpt_shutdown,
+	.tick_resume = mfgpt_shutdown,
+	.set_next_event = mfgpt_next_event,
+	.rating = 250,
+};
+
+static irqreturn_t mfgpt_tick(int irq, void *dev_id)
+{
+	uint16_t val = cs5535_mfgpt_read(cs5535_event_clock, MFGPT_REG_SETUP);
+
+	/* See if the interrupt was for us */
+	if (!(val & (MFGPT_SETUP_SETUP | MFGPT_SETUP_CMP2 | MFGPT_SETUP_CMP1)))
+		return IRQ_NONE;
+
+	/* Turn off the clock (and clear the event) */
+	disable_timer(cs5535_event_clock);
+
+	if (clockevent_state_detached(&cs5535_clockevent) ||
+	    clockevent_state_shutdown(&cs5535_clockevent))
+		return IRQ_HANDLED;
+
+	/* Clear the counter */
+	cs5535_mfgpt_write(cs5535_event_clock, MFGPT_REG_COUNTER, 0);
+
+	/* Restart the clock in periodic mode */
+
+	if (clockevent_state_periodic(&cs5535_clockevent))
+		cs5535_mfgpt_write(cs5535_event_clock, MFGPT_REG_SETUP,
+				MFGPT_SETUP_CNTEN | MFGPT_SETUP_CMP2);
+
+	cs5535_clockevent.event_handler(&cs5535_clockevent);
+	return IRQ_HANDLED;
+}
+
+static struct irqaction mfgptirq  = {
+	.handler = mfgpt_tick,
+	.flags = IRQF_NOBALANCING | IRQF_TIMER | IRQF_SHARED,
+	.name = DRV_NAME,
+};
+
+static int __init cs5535_mfgpt_init(void)
+{
+	struct cs5535_mfgpt_timer *timer;
+	int ret;
+	uint16_t val;
+
+	timer = cs5535_mfgpt_alloc_timer(MFGPT_TIMER_ANY, MFGPT_DOMAIN_WORKING);
+	if (!timer) {
+		printk(KERN_ERR DRV_NAME ": Could not allocate MFGPT timer\n");
+		return -ENODEV;
+	}
+	cs5535_event_clock = timer;
+
+	/* Set up the IRQ on the MFGPT side */
+	if (cs5535_mfgpt_setup_irq(timer, MFGPT_CMP2, &timer_irq)) {
+		printk(KERN_ERR DRV_NAME ": Could not set up IRQ %d\n",
+				timer_irq);
+		goto err_timer;
+	}
+
+	/* And register it with the kernel */
+	ret = setup_irq(timer_irq, &mfgptirq);
+	if (ret) {
+		printk(KERN_ERR DRV_NAME ": Unable to set up the interrupt.\n");
+		goto err_irq;
+	}
+
+	/* Set the clock scale and enable the event mode for CMP2 */
+	val = MFGPT_SCALE | (3 << 8);
+
+	cs5535_mfgpt_write(cs5535_event_clock, MFGPT_REG_SETUP, val);
+
+	/* Set up the clock event */
+	printk(KERN_INFO DRV_NAME
+		": Registering MFGPT timer as a clock event, using IRQ %d\n",
+		timer_irq);
+	clockevents_config_and_register(&cs5535_clockevent, MFGPT_HZ,
+					0xF, 0xFFFE);
+
+	return 0;
+
+err_irq:
+	cs5535_mfgpt_release_irq(cs5535_event_clock, MFGPT_CMP2, &timer_irq);
+err_timer:
+	cs5535_mfgpt_free_timer(cs5535_event_clock);
+	printk(KERN_ERR DRV_NAME ": Unable to set up the MFGPT clock source\n");
+	return -EIO;
+}
+
+module_init(cs5535_mfgpt_init);
+
+MODULE_AUTHOR("Andres Salomon <dilinger@queued.net>");
+MODULE_DESCRIPTION("CS5535/CS5536 MFGPT clock event driver");
+MODULE_LICENSE("GPL");

drivers/clocksource/dummy_timer.c

@@ -0,0 +1,40 @@
+/*
+ *  linux/drivers/clocksource/dummy_timer.c
+ *
+ *  Copyright (C) 2013 ARM Ltd.
+ *  All Rights Reserved
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/clockchips.h>
+#include <linux/cpu.h>
+#include <linux/init.h>
+#include <linux/percpu.h>
+#include <linux/cpumask.h>
+
+static DEFINE_PER_CPU(struct clock_event_device, dummy_timer_evt);
+
+static int dummy_timer_starting_cpu(unsigned int cpu)
+{
+	struct clock_event_device *evt = per_cpu_ptr(&dummy_timer_evt, cpu);
+
+	evt->name	= "dummy_timer";
+	evt->features	= CLOCK_EVT_FEAT_PERIODIC |
+			  CLOCK_EVT_FEAT_ONESHOT |
+			  CLOCK_EVT_FEAT_DUMMY;
+	evt->rating	= 100;
+	evt->cpumask	= cpumask_of(cpu);
+
+	clockevents_register_device(evt);
+	return 0;
+}
+
+static int __init dummy_timer_register(void)
+{
+	return cpuhp_setup_state(CPUHP_AP_DUMMY_TIMER_STARTING,
+				 "clockevents/dummy_timer:starting",
+				 dummy_timer_starting_cpu, NULL);
+}
+early_initcall(dummy_timer_register);

drivers/clocksource/dw_apb_timer.c

@@ -0,0 +1,425 @@
+/*
+ * (C) Copyright 2009 Intel Corporation
+ * Author: Jacob Pan (jacob.jun.pan@intel.com)
+ *
+ * Shared with ARM platforms, Jamie Iles, Picochip 2011
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Support for the Synopsys DesignWare APB Timers.
+ */
+#include <linux/dw_apb_timer.h>
+#include <linux/delay.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/slab.h>
+
+#define APBT_MIN_PERIOD			4
+#define APBT_MIN_DELTA_USEC		200
+
+#define APBTMR_N_LOAD_COUNT		0x00
+#define APBTMR_N_CURRENT_VALUE		0x04
+#define APBTMR_N_CONTROL		0x08
+#define APBTMR_N_EOI			0x0c
+#define APBTMR_N_INT_STATUS		0x10
+
+#define APBTMRS_INT_STATUS		0xa0
+#define APBTMRS_EOI			0xa4
+#define APBTMRS_RAW_INT_STATUS		0xa8
+#define APBTMRS_COMP_VERSION		0xac
+
+#define APBTMR_CONTROL_ENABLE		(1 << 0)
+/* 1: periodic, 0:free running. */
+#define APBTMR_CONTROL_MODE_PERIODIC	(1 << 1)
+#define APBTMR_CONTROL_INT		(1 << 2)
+
+static inline struct dw_apb_clock_event_device *
+ced_to_dw_apb_ced(struct clock_event_device *evt)
+{
+	return container_of(evt, struct dw_apb_clock_event_device, ced);
+}
+
+static inline struct dw_apb_clocksource *
+clocksource_to_dw_apb_clocksource(struct clocksource *cs)
+{
+	return container_of(cs, struct dw_apb_clocksource, cs);
+}
+
+static inline u32 apbt_readl(struct dw_apb_timer *timer, unsigned long offs)
+{
+	return readl(timer->base + offs);
+}
+
+static inline void apbt_writel(struct dw_apb_timer *timer, u32 val,
+			unsigned long offs)
+{
+	writel(val, timer->base + offs);
+}
+
+static inline u32 apbt_readl_relaxed(struct dw_apb_timer *timer, unsigned long offs)
+{
+	return readl_relaxed(timer->base + offs);
+}
+
+static inline void apbt_writel_relaxed(struct dw_apb_timer *timer, u32 val,
+			unsigned long offs)
+{
+	writel_relaxed(val, timer->base + offs);
+}
+
+static void apbt_disable_int(struct dw_apb_timer *timer)
+{
+	u32 ctrl = apbt_readl(timer, APBTMR_N_CONTROL);
+
+	ctrl |= APBTMR_CONTROL_INT;
+	apbt_writel(timer, ctrl, APBTMR_N_CONTROL);
+}
+
+/**
+ * dw_apb_clockevent_pause() - stop the clock_event_device from running
+ *
+ * @dw_ced:	The APB clock to stop generating events.
+ */
+void dw_apb_clockevent_pause(struct dw_apb_clock_event_device *dw_ced)
+{
+	disable_irq(dw_ced->timer.irq);
+	apbt_disable_int(&dw_ced->timer);
+}
+
+static void apbt_eoi(struct dw_apb_timer *timer)
+{
+	apbt_readl_relaxed(timer, APBTMR_N_EOI);
+}
+
+static irqreturn_t dw_apb_clockevent_irq(int irq, void *data)
+{
+	struct clock_event_device *evt = data;
+	struct dw_apb_clock_event_device *dw_ced = ced_to_dw_apb_ced(evt);
+
+	if (!evt->event_handler) {
+		pr_info("Spurious APBT timer interrupt %d\n", irq);
+		return IRQ_NONE;
+	}
+
+	if (dw_ced->eoi)
+		dw_ced->eoi(&dw_ced->timer);
+
+	evt->event_handler(evt);
+	return IRQ_HANDLED;
+}
+
+static void apbt_enable_int(struct dw_apb_timer *timer)
+{
+	u32 ctrl = apbt_readl(timer, APBTMR_N_CONTROL);
+	/* clear pending intr */
+	apbt_readl(timer, APBTMR_N_EOI);
+	ctrl &= ~APBTMR_CONTROL_INT;
+	apbt_writel(timer, ctrl, APBTMR_N_CONTROL);
+}
+
+static int apbt_shutdown(struct clock_event_device *evt)
+{
+	struct dw_apb_clock_event_device *dw_ced = ced_to_dw_apb_ced(evt);
+	u32 ctrl;
+
+	pr_debug("%s CPU %d state=shutdown\n", __func__,
+		 cpumask_first(evt->cpumask));
+
+	ctrl = apbt_readl(&dw_ced->timer, APBTMR_N_CONTROL);
+	ctrl &= ~APBTMR_CONTROL_ENABLE;
+	apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL);
+	return 0;
+}
+
+static int apbt_set_oneshot(struct clock_event_device *evt)
+{
+	struct dw_apb_clock_event_device *dw_ced = ced_to_dw_apb_ced(evt);
+	u32 ctrl;
+
+	pr_debug("%s CPU %d state=oneshot\n", __func__,
+		 cpumask_first(evt->cpumask));
+
+	ctrl = apbt_readl(&dw_ced->timer, APBTMR_N_CONTROL);
+	/*
+	 * set free running mode, this mode will let timer reload max
+	 * timeout which will give time (3min on 25MHz clock) to rearm
+	 * the next event, therefore emulate the one-shot mode.
+	 */
+	ctrl &= ~APBTMR_CONTROL_ENABLE;
+	ctrl &= ~APBTMR_CONTROL_MODE_PERIODIC;
+
+	apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL);
+	/* write again to set free running mode */
+	apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL);
+
+	/*
+	 * DW APB p. 46, load counter with all 1s before starting free
+	 * running mode.
+	 */
+	apbt_writel(&dw_ced->timer, ~0, APBTMR_N_LOAD_COUNT);
+	ctrl &= ~APBTMR_CONTROL_INT;
+	ctrl |= APBTMR_CONTROL_ENABLE;
+	apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL);
+	return 0;
+}
+
+static int apbt_set_periodic(struct clock_event_device *evt)
+{
+	struct dw_apb_clock_event_device *dw_ced = ced_to_dw_apb_ced(evt);
+	unsigned long period = DIV_ROUND_UP(dw_ced->timer.freq, HZ);
+	u32 ctrl;
+
+	pr_debug("%s CPU %d state=periodic\n", __func__,
+		 cpumask_first(evt->cpumask));
+
+	ctrl = apbt_readl(&dw_ced->timer, APBTMR_N_CONTROL);
+	ctrl |= APBTMR_CONTROL_MODE_PERIODIC;
+	apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL);
+	/*
+	 * DW APB p. 46, have to disable timer before load counter,
+	 * may cause sync problem.
+	 */
+	ctrl &= ~APBTMR_CONTROL_ENABLE;
+	apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL);
+	udelay(1);
+	pr_debug("Setting clock period %lu for HZ %d\n", period, HZ);
+	apbt_writel(&dw_ced->timer, period, APBTMR_N_LOAD_COUNT);
+	ctrl |= APBTMR_CONTROL_ENABLE;
+	apbt_writel(&dw_ced->timer, ctrl, APBTMR_N_CONTROL);
+	return 0;
+}
+
+static int apbt_resume(struct clock_event_device *evt)
+{
+	struct dw_apb_clock_event_device *dw_ced = ced_to_dw_apb_ced(evt);
+
+	pr_debug("%s CPU %d state=resume\n", __func__,
+		 cpumask_first(evt->cpumask));
+
+	apbt_enable_int(&dw_ced->timer);
+	return 0;
+}
+
+static int apbt_next_event(unsigned long delta,
+			   struct clock_event_device *evt)
+{
+	u32 ctrl;
+	struct dw_apb_clock_event_device *dw_ced = ced_to_dw_apb_ced(evt);
+
+	/* Disable timer */
+	ctrl = apbt_readl_relaxed(&dw_ced->timer, APBTMR_N_CONTROL);
+	ctrl &= ~APBTMR_CONTROL_ENABLE;
+	apbt_writel_relaxed(&dw_ced->timer, ctrl, APBTMR_N_CONTROL);
+	/* write new count */
+	apbt_writel_relaxed(&dw_ced->timer, delta, APBTMR_N_LOAD_COUNT);
+	ctrl |= APBTMR_CONTROL_ENABLE;
+	apbt_writel_relaxed(&dw_ced->timer, ctrl, APBTMR_N_CONTROL);
+
+	return 0;
+}
+
+/**
+ * dw_apb_clockevent_init() - use an APB timer as a clock_event_device
+ *
+ * @cpu:	The CPU the events will be targeted at or -1 if CPU affiliation
+ *		isn't required.
+ * @name:	The name used for the timer and the IRQ for it.
+ * @rating:	The rating to give the timer.
+ * @base:	I/O base for the timer registers.
+ * @irq:	The interrupt number to use for the timer.
+ * @freq:	The frequency that the timer counts at.
+ *
+ * This creates a clock_event_device for using with the generic clock layer
+ * but does not start and register it.  This should be done with
+ * dw_apb_clockevent_register() as the next step.  If this is the first time
+ * it has been called for a timer then the IRQ will be requested, if not it
+ * just be enabled to allow CPU hotplug to avoid repeatedly requesting and
+ * releasing the IRQ.
+ */
+struct dw_apb_clock_event_device *
+dw_apb_clockevent_init(int cpu, const char *name, unsigned rating,
+		       void __iomem *base, int irq, unsigned long freq)
+{
+	struct dw_apb_clock_event_device *dw_ced =
+		kzalloc(sizeof(*dw_ced), GFP_KERNEL);
+	int err;
+
+	if (!dw_ced)
+		return NULL;
+
+	dw_ced->timer.base = base;
+	dw_ced->timer.irq = irq;
+	dw_ced->timer.freq = freq;
+
+	clockevents_calc_mult_shift(&dw_ced->ced, freq, APBT_MIN_PERIOD);
+	dw_ced->ced.max_delta_ns = clockevent_delta2ns(0x7fffffff,
+						       &dw_ced->ced);
+	dw_ced->ced.max_delta_ticks = 0x7fffffff;
+	dw_ced->ced.min_delta_ns = clockevent_delta2ns(5000, &dw_ced->ced);
+	dw_ced->ced.min_delta_ticks = 5000;
+	dw_ced->ced.cpumask = cpu < 0 ? cpu_possible_mask : cpumask_of(cpu);
+	dw_ced->ced.features = CLOCK_EVT_FEAT_PERIODIC |
+				CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_DYNIRQ;
+	dw_ced->ced.set_state_shutdown = apbt_shutdown;
+	dw_ced->ced.set_state_periodic = apbt_set_periodic;
+	dw_ced->ced.set_state_oneshot = apbt_set_oneshot;
+	dw_ced->ced.set_state_oneshot_stopped = apbt_shutdown;
+	dw_ced->ced.tick_resume = apbt_resume;
+	dw_ced->ced.set_next_event = apbt_next_event;
+	dw_ced->ced.irq = dw_ced->timer.irq;
+	dw_ced->ced.rating = rating;
+	dw_ced->ced.name = name;
+
+	dw_ced->irqaction.name		= dw_ced->ced.name;
+	dw_ced->irqaction.handler	= dw_apb_clockevent_irq;
+	dw_ced->irqaction.dev_id	= &dw_ced->ced;
+	dw_ced->irqaction.irq		= irq;
+	dw_ced->irqaction.flags		= IRQF_TIMER | IRQF_IRQPOLL |
+					  IRQF_NOBALANCING;
+
+	dw_ced->eoi = apbt_eoi;
+	err = setup_irq(irq, &dw_ced->irqaction);
+	if (err) {
+		pr_err("failed to request timer irq\n");
+		kfree(dw_ced);
+		dw_ced = NULL;
+	}
+
+	return dw_ced;
+}
+
+/**
+ * dw_apb_clockevent_resume() - resume a clock that has been paused.
+ *
+ * @dw_ced:	The APB clock to resume.
+ */
+void dw_apb_clockevent_resume(struct dw_apb_clock_event_device *dw_ced)
+{
+	enable_irq(dw_ced->timer.irq);
+}
+
+/**
+ * dw_apb_clockevent_stop() - stop the clock_event_device and release the IRQ.
+ *
+ * @dw_ced:	The APB clock to stop generating the events.
+ */
+void dw_apb_clockevent_stop(struct dw_apb_clock_event_device *dw_ced)
+{
+	free_irq(dw_ced->timer.irq, &dw_ced->ced);
+}
+
+/**
+ * dw_apb_clockevent_register() - register the clock with the generic layer
+ *
+ * @dw_ced:	The APB clock to register as a clock_event_device.
+ */
+void dw_apb_clockevent_register(struct dw_apb_clock_event_device *dw_ced)
+{
+	apbt_writel(&dw_ced->timer, 0, APBTMR_N_CONTROL);
+	clockevents_register_device(&dw_ced->ced);
+	apbt_enable_int(&dw_ced->timer);
+}
+
+/**
+ * dw_apb_clocksource_start() - start the clocksource counting.
+ *
+ * @dw_cs:	The clocksource to start.
+ *
+ * This is used to start the clocksource before registration and can be used
+ * to enable calibration of timers.
+ */
+void dw_apb_clocksource_start(struct dw_apb_clocksource *dw_cs)
+{
+	/*
+	 * start count down from 0xffff_ffff. this is done by toggling the
+	 * enable bit then load initial load count to ~0.
+	 */
+	u32 ctrl = apbt_readl(&dw_cs->timer, APBTMR_N_CONTROL);
+
+	ctrl &= ~APBTMR_CONTROL_ENABLE;
+	apbt_writel(&dw_cs->timer, ctrl, APBTMR_N_CONTROL);
+	apbt_writel(&dw_cs->timer, ~0, APBTMR_N_LOAD_COUNT);
+	/* enable, mask interrupt */
+	ctrl &= ~APBTMR_CONTROL_MODE_PERIODIC;
+	ctrl |= (APBTMR_CONTROL_ENABLE | APBTMR_CONTROL_INT);
+	apbt_writel(&dw_cs->timer, ctrl, APBTMR_N_CONTROL);
+	/* read it once to get cached counter value initialized */
+	dw_apb_clocksource_read(dw_cs);
+}
+
+static u64 __apbt_read_clocksource(struct clocksource *cs)
+{
+	u32 current_count;
+	struct dw_apb_clocksource *dw_cs =
+		clocksource_to_dw_apb_clocksource(cs);
+
+	current_count = apbt_readl_relaxed(&dw_cs->timer,
+					APBTMR_N_CURRENT_VALUE);
+
+	return (u64)~current_count;
+}
+
+static void apbt_restart_clocksource(struct clocksource *cs)
+{
+	struct dw_apb_clocksource *dw_cs =
+		clocksource_to_dw_apb_clocksource(cs);
+
+	dw_apb_clocksource_start(dw_cs);
+}
+
+/**
+ * dw_apb_clocksource_init() - use an APB timer as a clocksource.
+ *
+ * @rating:	The rating to give the clocksource.
+ * @name:	The name for the clocksource.
+ * @base:	The I/O base for the timer registers.
+ * @freq:	The frequency that the timer counts at.
+ *
+ * This creates a clocksource using an APB timer but does not yet register it
+ * with the clocksource system.  This should be done with
+ * dw_apb_clocksource_register() as the next step.
+ */
+struct dw_apb_clocksource *
+dw_apb_clocksource_init(unsigned rating, const char *name, void __iomem *base,
+			unsigned long freq)
+{
+	struct dw_apb_clocksource *dw_cs = kzalloc(sizeof(*dw_cs), GFP_KERNEL);
+
+	if (!dw_cs)
+		return NULL;
+
+	dw_cs->timer.base = base;
+	dw_cs->timer.freq = freq;
+	dw_cs->cs.name = name;
+	dw_cs->cs.rating = rating;
+	dw_cs->cs.read = __apbt_read_clocksource;
+	dw_cs->cs.mask = CLOCKSOURCE_MASK(32);
+	dw_cs->cs.flags = CLOCK_SOURCE_IS_CONTINUOUS;
+	dw_cs->cs.resume = apbt_restart_clocksource;
+
+	return dw_cs;
+}
+
+/**
+ * dw_apb_clocksource_register() - register the APB clocksource.
+ *
+ * @dw_cs:	The clocksource to register.
+ */
+void dw_apb_clocksource_register(struct dw_apb_clocksource *dw_cs)
+{
+	clocksource_register_hz(&dw_cs->cs, dw_cs->timer.freq);
+}
+
+/**
+ * dw_apb_clocksource_read() - read the current value of a clocksource.
+ *
+ * @dw_cs:	The clocksource to read.
+ */
+u64 dw_apb_clocksource_read(struct dw_apb_clocksource *dw_cs)
+{
+	return (u64)~apbt_readl(&dw_cs->timer, APBTMR_N_CURRENT_VALUE);
+}

drivers/clocksource/dw_apb_timer_of.c

@@ -0,0 +1,171 @@
+/*
+ * Copyright (C) 2012 Altera Corporation
+ * Copyright (c) 2011 Picochip Ltd., Jamie Iles
+ *
+ * Modified from mach-picoxcell/time.c
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/delay.h>
+#include <linux/dw_apb_timer.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/clk.h>
+#include <linux/sched_clock.h>
+
+static void __init timer_get_base_and_rate(struct device_node *np,
+				    void __iomem **base, u32 *rate)
+{
+	struct clk *timer_clk;
+	struct clk *pclk;
+
+	*base = of_iomap(np, 0);
+
+	if (!*base)
+		panic("Unable to map regs for %s", np->name);
+
+	/*
+	 * Not all implementations use a periphal clock, so don't panic
+	 * if it's not present
+	 */
+	pclk = of_clk_get_by_name(np, "pclk");
+	if (!IS_ERR(pclk))
+		if (clk_prepare_enable(pclk))
+			pr_warn("pclk for %s is present, but could not be activated\n",
+				np->name);
+
+	timer_clk = of_clk_get_by_name(np, "timer");
+	if (IS_ERR(timer_clk))
+		goto try_clock_freq;
+
+	if (!clk_prepare_enable(timer_clk)) {
+		*rate = clk_get_rate(timer_clk);
+		return;
+	}
+
+try_clock_freq:
+	if (of_property_read_u32(np, "clock-freq", rate) &&
+	    of_property_read_u32(np, "clock-frequency", rate))
+		panic("No clock nor clock-frequency property for %s", np->name);
+}
+
+static void __init add_clockevent(struct device_node *event_timer)
+{
+	void __iomem *iobase;
+	struct dw_apb_clock_event_device *ced;
+	u32 irq, rate;
+
+	irq = irq_of_parse_and_map(event_timer, 0);
+	if (irq == 0)
+		panic("No IRQ for clock event timer");
+
+	timer_get_base_and_rate(event_timer, &iobase, &rate);
+
+	ced = dw_apb_clockevent_init(0, event_timer->name, 300, iobase, irq,
+				     rate);
+	if (!ced)
+		panic("Unable to initialise clockevent device");
+
+	dw_apb_clockevent_register(ced);
+}
+
+static void __iomem *sched_io_base;
+static u32 sched_rate;
+
+static void __init add_clocksource(struct device_node *source_timer)
+{
+	void __iomem *iobase;
+	struct dw_apb_clocksource *cs;
+	u32 rate;
+
+	timer_get_base_and_rate(source_timer, &iobase, &rate);
+
+	cs = dw_apb_clocksource_init(300, source_timer->name, iobase, rate);
+	if (!cs)
+		panic("Unable to initialise clocksource device");
+
+	dw_apb_clocksource_start(cs);
+	dw_apb_clocksource_register(cs);
+
+	/*
+	 * Fallback to use the clocksource as sched_clock if no separate
+	 * timer is found. sched_io_base then points to the current_value
+	 * register of the clocksource timer.
+	 */
+	sched_io_base = iobase + 0x04;
+	sched_rate = rate;
+}
+
+static u64 notrace read_sched_clock(void)
+{
+	return ~readl_relaxed(sched_io_base);
+}
+
+static const struct of_device_id sptimer_ids[] __initconst = {
+	{ .compatible = "picochip,pc3x2-rtc" },
+	{ /* Sentinel */ },
+};
+
+static void __init init_sched_clock(void)
+{
+	struct device_node *sched_timer;
+
+	sched_timer = of_find_matching_node(NULL, sptimer_ids);
+	if (sched_timer) {
+		timer_get_base_and_rate(sched_timer, &sched_io_base,
+					&sched_rate);
+		of_node_put(sched_timer);
+	}
+
+	sched_clock_register(read_sched_clock, 32, sched_rate);
+}
+
+#ifdef CONFIG_ARM
+static unsigned long dw_apb_delay_timer_read(void)
+{
+	return ~readl_relaxed(sched_io_base);
+}
+
+static struct delay_timer dw_apb_delay_timer = {
+	.read_current_timer	= dw_apb_delay_timer_read,
+};
+#endif
+
+static int num_called;
+static int __init dw_apb_timer_init(struct device_node *timer)
+{
+	switch (num_called) {
+	case 1:
+		pr_debug("%s: found clocksource timer\n", __func__);
+		add_clocksource(timer);
+		init_sched_clock();
+#ifdef CONFIG_ARM
+		dw_apb_delay_timer.freq = sched_rate;
+		register_current_timer_delay(&dw_apb_delay_timer);
+#endif
+		break;
+	default:
+		pr_debug("%s: found clockevent timer\n", __func__);
+		add_clockevent(timer);
+		break;
+	}
+
+	num_called++;
+
+	return 0;
+}
+TIMER_OF_DECLARE(pc3x2_timer, "picochip,pc3x2-timer", dw_apb_timer_init);
+TIMER_OF_DECLARE(apb_timer_osc, "snps,dw-apb-timer-osc", dw_apb_timer_init);
+TIMER_OF_DECLARE(apb_timer_sp, "snps,dw-apb-timer-sp", dw_apb_timer_init);
+TIMER_OF_DECLARE(apb_timer, "snps,dw-apb-timer", dw_apb_timer_init);

drivers/clocksource/em_sti.c

@@ -0,0 +1,388 @@
+/*
+ * Emma Mobile Timer Support - STI
+ *
+ *  Copyright (C) 2012 Magnus Damm
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/spinlock.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/irq.h>
+#include <linux/err.h>
+#include <linux/delay.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+
+enum { USER_CLOCKSOURCE, USER_CLOCKEVENT, USER_NR };
+
+struct em_sti_priv {
+	void __iomem *base;
+	struct clk *clk;
+	struct platform_device *pdev;
+	unsigned int active[USER_NR];
+	unsigned long rate;
+	raw_spinlock_t lock;
+	struct clock_event_device ced;
+	struct clocksource cs;
+};
+
+#define STI_CONTROL 0x00
+#define STI_COMPA_H 0x10
+#define STI_COMPA_L 0x14
+#define STI_COMPB_H 0x18
+#define STI_COMPB_L 0x1c
+#define STI_COUNT_H 0x20
+#define STI_COUNT_L 0x24
+#define STI_COUNT_RAW_H 0x28
+#define STI_COUNT_RAW_L 0x2c
+#define STI_SET_H 0x30
+#define STI_SET_L 0x34
+#define STI_INTSTATUS 0x40
+#define STI_INTRAWSTATUS 0x44
+#define STI_INTENSET 0x48
+#define STI_INTENCLR 0x4c
+#define STI_INTFFCLR 0x50
+
+static inline unsigned long em_sti_read(struct em_sti_priv *p, int offs)
+{
+	return ioread32(p->base + offs);
+}
+
+static inline void em_sti_write(struct em_sti_priv *p, int offs,
+				unsigned long value)
+{
+	iowrite32(value, p->base + offs);
+}
+
+static int em_sti_enable(struct em_sti_priv *p)
+{
+	int ret;
+
+	/* enable clock */
+	ret = clk_enable(p->clk);
+	if (ret) {
+		dev_err(&p->pdev->dev, "cannot enable clock\n");
+		return ret;
+	}
+
+	/* reset the counter */
+	em_sti_write(p, STI_SET_H, 0x40000000);
+	em_sti_write(p, STI_SET_L, 0x00000000);
+
+	/* mask and clear pending interrupts */
+	em_sti_write(p, STI_INTENCLR, 3);
+	em_sti_write(p, STI_INTFFCLR, 3);
+
+	/* enable updates of counter registers */
+	em_sti_write(p, STI_CONTROL, 1);
+
+	return 0;
+}
+
+static void em_sti_disable(struct em_sti_priv *p)
+{
+	/* mask interrupts */
+	em_sti_write(p, STI_INTENCLR, 3);
+
+	/* stop clock */
+	clk_disable(p->clk);
+}
+
+static u64 em_sti_count(struct em_sti_priv *p)
+{
+	u64 ticks;
+	unsigned long flags;
+
+	/* the STI hardware buffers the 48-bit count, but to
+	 * break it out into two 32-bit access the registers
+	 * must be accessed in a certain order.
+	 * Always read STI_COUNT_H before STI_COUNT_L.
+	 */
+	raw_spin_lock_irqsave(&p->lock, flags);
+	ticks = (u64)(em_sti_read(p, STI_COUNT_H) & 0xffff) << 32;
+	ticks |= em_sti_read(p, STI_COUNT_L);
+	raw_spin_unlock_irqrestore(&p->lock, flags);
+
+	return ticks;
+}
+
+static u64 em_sti_set_next(struct em_sti_priv *p, u64 next)
+{
+	unsigned long flags;
+
+	raw_spin_lock_irqsave(&p->lock, flags);
+
+	/* mask compare A interrupt */
+	em_sti_write(p, STI_INTENCLR, 1);
+
+	/* update compare A value */
+	em_sti_write(p, STI_COMPA_H, next >> 32);
+	em_sti_write(p, STI_COMPA_L, next & 0xffffffff);
+
+	/* clear compare A interrupt source */
+	em_sti_write(p, STI_INTFFCLR, 1);
+
+	/* unmask compare A interrupt */
+	em_sti_write(p, STI_INTENSET, 1);
+
+	raw_spin_unlock_irqrestore(&p->lock, flags);
+
+	return next;
+}
+
+static irqreturn_t em_sti_interrupt(int irq, void *dev_id)
+{
+	struct em_sti_priv *p = dev_id;
+
+	p->ced.event_handler(&p->ced);
+	return IRQ_HANDLED;
+}
+
+static int em_sti_start(struct em_sti_priv *p, unsigned int user)
+{
+	unsigned long flags;
+	int used_before;
+	int ret = 0;
+
+	raw_spin_lock_irqsave(&p->lock, flags);
+	used_before = p->active[USER_CLOCKSOURCE] | p->active[USER_CLOCKEVENT];
+	if (!used_before)
+		ret = em_sti_enable(p);
+
+	if (!ret)
+		p->active[user] = 1;
+	raw_spin_unlock_irqrestore(&p->lock, flags);
+
+	return ret;
+}
+
+static void em_sti_stop(struct em_sti_priv *p, unsigned int user)
+{
+	unsigned long flags;
+	int used_before, used_after;
+
+	raw_spin_lock_irqsave(&p->lock, flags);
+	used_before = p->active[USER_CLOCKSOURCE] | p->active[USER_CLOCKEVENT];
+	p->active[user] = 0;
+	used_after = p->active[USER_CLOCKSOURCE] | p->active[USER_CLOCKEVENT];
+
+	if (used_before && !used_after)
+		em_sti_disable(p);
+	raw_spin_unlock_irqrestore(&p->lock, flags);
+}
+
+static struct em_sti_priv *cs_to_em_sti(struct clocksource *cs)
+{
+	return container_of(cs, struct em_sti_priv, cs);
+}
+
+static u64 em_sti_clocksource_read(struct clocksource *cs)
+{
+	return em_sti_count(cs_to_em_sti(cs));
+}
+
+static int em_sti_clocksource_enable(struct clocksource *cs)
+{
+	struct em_sti_priv *p = cs_to_em_sti(cs);
+
+	return em_sti_start(p, USER_CLOCKSOURCE);
+}
+
+static void em_sti_clocksource_disable(struct clocksource *cs)
+{
+	em_sti_stop(cs_to_em_sti(cs), USER_CLOCKSOURCE);
+}
+
+static void em_sti_clocksource_resume(struct clocksource *cs)
+{
+	em_sti_clocksource_enable(cs);
+}
+
+static int em_sti_register_clocksource(struct em_sti_priv *p)
+{
+	struct clocksource *cs = &p->cs;
+
+	cs->name = dev_name(&p->pdev->dev);
+	cs->rating = 200;
+	cs->read = em_sti_clocksource_read;
+	cs->enable = em_sti_clocksource_enable;
+	cs->disable = em_sti_clocksource_disable;
+	cs->suspend = em_sti_clocksource_disable;
+	cs->resume = em_sti_clocksource_resume;
+	cs->mask = CLOCKSOURCE_MASK(48);
+	cs->flags = CLOCK_SOURCE_IS_CONTINUOUS;
+
+	dev_info(&p->pdev->dev, "used as clock source\n");
+
+	clocksource_register_hz(cs, p->rate);
+	return 0;
+}
+
+static struct em_sti_priv *ced_to_em_sti(struct clock_event_device *ced)
+{
+	return container_of(ced, struct em_sti_priv, ced);
+}
+
+static int em_sti_clock_event_shutdown(struct clock_event_device *ced)
+{
+	struct em_sti_priv *p = ced_to_em_sti(ced);
+	em_sti_stop(p, USER_CLOCKEVENT);
+	return 0;
+}
+
+static int em_sti_clock_event_set_oneshot(struct clock_event_device *ced)
+{
+	struct em_sti_priv *p = ced_to_em_sti(ced);
+
+	dev_info(&p->pdev->dev, "used for oneshot clock events\n");
+	em_sti_start(p, USER_CLOCKEVENT);
+	return 0;
+}
+
+static int em_sti_clock_event_next(unsigned long delta,
+				   struct clock_event_device *ced)
+{
+	struct em_sti_priv *p = ced_to_em_sti(ced);
+	u64 next;
+	int safe;
+
+	next = em_sti_set_next(p, em_sti_count(p) + delta);
+	safe = em_sti_count(p) < (next - 1);
+
+	return !safe;
+}
+
+static void em_sti_register_clockevent(struct em_sti_priv *p)
+{
+	struct clock_event_device *ced = &p->ced;
+
+	ced->name = dev_name(&p->pdev->dev);
+	ced->features = CLOCK_EVT_FEAT_ONESHOT;
+	ced->rating = 200;
+	ced->cpumask = cpu_possible_mask;
+	ced->set_next_event = em_sti_clock_event_next;
+	ced->set_state_shutdown = em_sti_clock_event_shutdown;
+	ced->set_state_oneshot = em_sti_clock_event_set_oneshot;
+
+	dev_info(&p->pdev->dev, "used for clock events\n");
+
+	clockevents_config_and_register(ced, p->rate, 2, 0xffffffff);
+}
+
+static int em_sti_probe(struct platform_device *pdev)
+{
+	struct em_sti_priv *p;
+	struct resource *res;
+	int irq;
+	int ret;
+
+	p = devm_kzalloc(&pdev->dev, sizeof(*p), GFP_KERNEL);
+	if (p == NULL)
+		return -ENOMEM;
+
+	p->pdev = pdev;
+	platform_set_drvdata(pdev, p);
+
+	irq = platform_get_irq(pdev, 0);
+	if (irq < 0) {
+		dev_err(&pdev->dev, "failed to get irq\n");
+		return irq;
+	}
+
+	/* map memory, let base point to the STI instance */
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	p->base = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(p->base))
+		return PTR_ERR(p->base);
+
+	ret = devm_request_irq(&pdev->dev, irq, em_sti_interrupt,
+			       IRQF_TIMER | IRQF_IRQPOLL | IRQF_NOBALANCING,
+			       dev_name(&pdev->dev), p);
+	if (ret) {
+		dev_err(&pdev->dev, "failed to request low IRQ\n");
+		return ret;
+	}
+
+	/* get hold of clock */
+	p->clk = devm_clk_get(&pdev->dev, "sclk");
+	if (IS_ERR(p->clk)) {
+		dev_err(&pdev->dev, "cannot get clock\n");
+		return PTR_ERR(p->clk);
+	}
+
+	ret = clk_prepare(p->clk);
+	if (ret < 0) {
+		dev_err(&pdev->dev, "cannot prepare clock\n");
+		return ret;
+	}
+
+	ret = clk_enable(p->clk);
+	if (ret < 0) {
+		dev_err(&p->pdev->dev, "cannot enable clock\n");
+		clk_unprepare(p->clk);
+		return ret;
+	}
+	p->rate = clk_get_rate(p->clk);
+	clk_disable(p->clk);
+
+	raw_spin_lock_init(&p->lock);
+	em_sti_register_clockevent(p);
+	em_sti_register_clocksource(p);
+	return 0;
+}
+
+static int em_sti_remove(struct platform_device *pdev)
+{
+	return -EBUSY; /* cannot unregister clockevent and clocksource */
+}
+
+static const struct of_device_id em_sti_dt_ids[] = {
+	{ .compatible = "renesas,em-sti", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, em_sti_dt_ids);
+
+static struct platform_driver em_sti_device_driver = {
+	.probe		= em_sti_probe,
+	.remove		= em_sti_remove,
+	.driver		= {
+		.name	= "em_sti",
+		.of_match_table = em_sti_dt_ids,
+	}
+};
+
+static int __init em_sti_init(void)
+{
+	return platform_driver_register(&em_sti_device_driver);
+}
+
+static void __exit em_sti_exit(void)
+{
+	platform_driver_unregister(&em_sti_device_driver);
+}
+
+subsys_initcall(em_sti_init);
+module_exit(em_sti_exit);
+
+MODULE_AUTHOR("Magnus Damm");
+MODULE_DESCRIPTION("Renesas Emma Mobile STI Timer Driver");
+MODULE_LICENSE("GPL v2");

drivers/clocksource/exynos_mct.c

@@ -0,0 +1,627 @@
+/* linux/arch/arm/mach-exynos4/mct.c
+ *
+ * Copyright (c) 2011 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com
+ *
+ * EXYNOS4 MCT(Multi-Core Timer) support
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/cpu.h>
+#include <linux/platform_device.h>
+#include <linux/delay.h>
+#include <linux/percpu.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/clocksource.h>
+#include <linux/sched_clock.h>
+
+#define EXYNOS4_MCTREG(x)		(x)
+#define EXYNOS4_MCT_G_CNT_L		EXYNOS4_MCTREG(0x100)
+#define EXYNOS4_MCT_G_CNT_U		EXYNOS4_MCTREG(0x104)
+#define EXYNOS4_MCT_G_CNT_WSTAT		EXYNOS4_MCTREG(0x110)
+#define EXYNOS4_MCT_G_COMP0_L		EXYNOS4_MCTREG(0x200)
+#define EXYNOS4_MCT_G_COMP0_U		EXYNOS4_MCTREG(0x204)
+#define EXYNOS4_MCT_G_COMP0_ADD_INCR	EXYNOS4_MCTREG(0x208)
+#define EXYNOS4_MCT_G_TCON		EXYNOS4_MCTREG(0x240)
+#define EXYNOS4_MCT_G_INT_CSTAT		EXYNOS4_MCTREG(0x244)
+#define EXYNOS4_MCT_G_INT_ENB		EXYNOS4_MCTREG(0x248)
+#define EXYNOS4_MCT_G_WSTAT		EXYNOS4_MCTREG(0x24C)
+#define _EXYNOS4_MCT_L_BASE		EXYNOS4_MCTREG(0x300)
+#define EXYNOS4_MCT_L_BASE(x)		(_EXYNOS4_MCT_L_BASE + (0x100 * x))
+#define EXYNOS4_MCT_L_MASK		(0xffffff00)
+
+#define MCT_L_TCNTB_OFFSET		(0x00)
+#define MCT_L_ICNTB_OFFSET		(0x08)
+#define MCT_L_TCON_OFFSET		(0x20)
+#define MCT_L_INT_CSTAT_OFFSET		(0x30)
+#define MCT_L_INT_ENB_OFFSET		(0x34)
+#define MCT_L_WSTAT_OFFSET		(0x40)
+#define MCT_G_TCON_START		(1 << 8)
+#define MCT_G_TCON_COMP0_AUTO_INC	(1 << 1)
+#define MCT_G_TCON_COMP0_ENABLE		(1 << 0)
+#define MCT_L_TCON_INTERVAL_MODE	(1 << 2)
+#define MCT_L_TCON_INT_START		(1 << 1)
+#define MCT_L_TCON_TIMER_START		(1 << 0)
+
+#define TICK_BASE_CNT	1
+
+enum {
+	MCT_INT_SPI,
+	MCT_INT_PPI
+};
+
+enum {
+	MCT_G0_IRQ,
+	MCT_G1_IRQ,
+	MCT_G2_IRQ,
+	MCT_G3_IRQ,
+	MCT_L0_IRQ,
+	MCT_L1_IRQ,
+	MCT_L2_IRQ,
+	MCT_L3_IRQ,
+	MCT_L4_IRQ,
+	MCT_L5_IRQ,
+	MCT_L6_IRQ,
+	MCT_L7_IRQ,
+	MCT_NR_IRQS,
+};
+
+static void __iomem *reg_base;
+static unsigned long clk_rate;
+static unsigned int mct_int_type;
+static int mct_irqs[MCT_NR_IRQS];
+
+struct mct_clock_event_device {
+	struct clock_event_device evt;
+	unsigned long base;
+	char name[10];
+};
+
+static void exynos4_mct_write(unsigned int value, unsigned long offset)
+{
+	unsigned long stat_addr;
+	u32 mask;
+	u32 i;
+
+	writel_relaxed(value, reg_base + offset);
+
+	if (likely(offset >= EXYNOS4_MCT_L_BASE(0))) {
+		stat_addr = (offset & EXYNOS4_MCT_L_MASK) + MCT_L_WSTAT_OFFSET;
+		switch (offset & ~EXYNOS4_MCT_L_MASK) {
+		case MCT_L_TCON_OFFSET:
+			mask = 1 << 3;		/* L_TCON write status */
+			break;
+		case MCT_L_ICNTB_OFFSET:
+			mask = 1 << 1;		/* L_ICNTB write status */
+			break;
+		case MCT_L_TCNTB_OFFSET:
+			mask = 1 << 0;		/* L_TCNTB write status */
+			break;
+		default:
+			return;
+		}
+	} else {
+		switch (offset) {
+		case EXYNOS4_MCT_G_TCON:
+			stat_addr = EXYNOS4_MCT_G_WSTAT;
+			mask = 1 << 16;		/* G_TCON write status */
+			break;
+		case EXYNOS4_MCT_G_COMP0_L:
+			stat_addr = EXYNOS4_MCT_G_WSTAT;
+			mask = 1 << 0;		/* G_COMP0_L write status */
+			break;
+		case EXYNOS4_MCT_G_COMP0_U:
+			stat_addr = EXYNOS4_MCT_G_WSTAT;
+			mask = 1 << 1;		/* G_COMP0_U write status */
+			break;
+		case EXYNOS4_MCT_G_COMP0_ADD_INCR:
+			stat_addr = EXYNOS4_MCT_G_WSTAT;
+			mask = 1 << 2;		/* G_COMP0_ADD_INCR w status */
+			break;
+		case EXYNOS4_MCT_G_CNT_L:
+			stat_addr = EXYNOS4_MCT_G_CNT_WSTAT;
+			mask = 1 << 0;		/* G_CNT_L write status */
+			break;
+		case EXYNOS4_MCT_G_CNT_U:
+			stat_addr = EXYNOS4_MCT_G_CNT_WSTAT;
+			mask = 1 << 1;		/* G_CNT_U write status */
+			break;
+		default:
+			return;
+		}
+	}
+
+	/* Wait maximum 1 ms until written values are applied */
+	for (i = 0; i < loops_per_jiffy / 1000 * HZ; i++)
+		if (readl_relaxed(reg_base + stat_addr) & mask) {
+			writel_relaxed(mask, reg_base + stat_addr);
+			return;
+		}
+
+	panic("MCT hangs after writing %d (offset:0x%lx)\n", value, offset);
+}
+
+/* Clocksource handling */
+static void exynos4_mct_frc_start(void)
+{
+	u32 reg;
+
+	reg = readl_relaxed(reg_base + EXYNOS4_MCT_G_TCON);
+	reg |= MCT_G_TCON_START;
+	exynos4_mct_write(reg, EXYNOS4_MCT_G_TCON);
+}
+
+/**
+ * exynos4_read_count_64 - Read all 64-bits of the global counter
+ *
+ * This will read all 64-bits of the global counter taking care to make sure
+ * that the upper and lower half match.  Note that reading the MCT can be quite
+ * slow (hundreds of nanoseconds) so you should use the 32-bit (lower half
+ * only) version when possible.
+ *
+ * Returns the number of cycles in the global counter.
+ */
+static u64 exynos4_read_count_64(void)
+{
+	unsigned int lo, hi;
+	u32 hi2 = readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_U);
+
+	do {
+		hi = hi2;
+		lo = readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_L);
+		hi2 = readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_U);
+	} while (hi != hi2);
+
+	return ((u64)hi << 32) | lo;
+}
+
+/**
+ * exynos4_read_count_32 - Read the lower 32-bits of the global counter
+ *
+ * This will read just the lower 32-bits of the global counter.  This is marked
+ * as notrace so it can be used by the scheduler clock.
+ *
+ * Returns the number of cycles in the global counter (lower 32 bits).
+ */
+static u32 notrace exynos4_read_count_32(void)
+{
+	return readl_relaxed(reg_base + EXYNOS4_MCT_G_CNT_L);
+}
+
+static u64 exynos4_frc_read(struct clocksource *cs)
+{
+	return exynos4_read_count_32();
+}
+
+static void exynos4_frc_resume(struct clocksource *cs)
+{
+	exynos4_mct_frc_start();
+}
+
+static struct clocksource mct_frc = {
+	.name		= "mct-frc",
+	.rating		= 450,	/* use value higher than ARM arch timer */
+	.read		= exynos4_frc_read,
+	.mask		= CLOCKSOURCE_MASK(32),
+	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
+	.resume		= exynos4_frc_resume,
+};
+
+static u64 notrace exynos4_read_sched_clock(void)
+{
+	return exynos4_read_count_32();
+}
+
+#if defined(CONFIG_ARM)
+static struct delay_timer exynos4_delay_timer;
+
+static cycles_t exynos4_read_current_timer(void)
+{
+	BUILD_BUG_ON_MSG(sizeof(cycles_t) != sizeof(u32),
+			 "cycles_t needs to move to 32-bit for ARM64 usage");
+	return exynos4_read_count_32();
+}
+#endif
+
+static int __init exynos4_clocksource_init(void)
+{
+	exynos4_mct_frc_start();
+
+#if defined(CONFIG_ARM)
+	exynos4_delay_timer.read_current_timer = &exynos4_read_current_timer;
+	exynos4_delay_timer.freq = clk_rate;
+	register_current_timer_delay(&exynos4_delay_timer);
+#endif
+
+	if (clocksource_register_hz(&mct_frc, clk_rate))
+		panic("%s: can't register clocksource\n", mct_frc.name);
+
+	sched_clock_register(exynos4_read_sched_clock, 32, clk_rate);
+
+	return 0;
+}
+
+static void exynos4_mct_comp0_stop(void)
+{
+	unsigned int tcon;
+
+	tcon = readl_relaxed(reg_base + EXYNOS4_MCT_G_TCON);
+	tcon &= ~(MCT_G_TCON_COMP0_ENABLE | MCT_G_TCON_COMP0_AUTO_INC);
+
+	exynos4_mct_write(tcon, EXYNOS4_MCT_G_TCON);
+	exynos4_mct_write(0, EXYNOS4_MCT_G_INT_ENB);
+}
+
+static void exynos4_mct_comp0_start(bool periodic, unsigned long cycles)
+{
+	unsigned int tcon;
+	u64 comp_cycle;
+
+	tcon = readl_relaxed(reg_base + EXYNOS4_MCT_G_TCON);
+
+	if (periodic) {
+		tcon |= MCT_G_TCON_COMP0_AUTO_INC;
+		exynos4_mct_write(cycles, EXYNOS4_MCT_G_COMP0_ADD_INCR);
+	}
+
+	comp_cycle = exynos4_read_count_64() + cycles;
+	exynos4_mct_write((u32)comp_cycle, EXYNOS4_MCT_G_COMP0_L);
+	exynos4_mct_write((u32)(comp_cycle >> 32), EXYNOS4_MCT_G_COMP0_U);
+
+	exynos4_mct_write(0x1, EXYNOS4_MCT_G_INT_ENB);
+
+	tcon |= MCT_G_TCON_COMP0_ENABLE;
+	exynos4_mct_write(tcon , EXYNOS4_MCT_G_TCON);
+}
+
+static int exynos4_comp_set_next_event(unsigned long cycles,
+				       struct clock_event_device *evt)
+{
+	exynos4_mct_comp0_start(false, cycles);
+
+	return 0;
+}
+
+static int mct_set_state_shutdown(struct clock_event_device *evt)
+{
+	exynos4_mct_comp0_stop();
+	return 0;
+}
+
+static int mct_set_state_periodic(struct clock_event_device *evt)
+{
+	unsigned long cycles_per_jiffy;
+
+	cycles_per_jiffy = (((unsigned long long)NSEC_PER_SEC / HZ * evt->mult)
+			    >> evt->shift);
+	exynos4_mct_comp0_stop();
+	exynos4_mct_comp0_start(true, cycles_per_jiffy);
+	return 0;
+}
+
+static struct clock_event_device mct_comp_device = {
+	.name			= "mct-comp",
+	.features		= CLOCK_EVT_FEAT_PERIODIC |
+				  CLOCK_EVT_FEAT_ONESHOT,
+	.rating			= 250,
+	.set_next_event		= exynos4_comp_set_next_event,
+	.set_state_periodic	= mct_set_state_periodic,
+	.set_state_shutdown	= mct_set_state_shutdown,
+	.set_state_oneshot	= mct_set_state_shutdown,
+	.set_state_oneshot_stopped = mct_set_state_shutdown,
+	.tick_resume		= mct_set_state_shutdown,
+};
+
+static irqreturn_t exynos4_mct_comp_isr(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	exynos4_mct_write(0x1, EXYNOS4_MCT_G_INT_CSTAT);
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static struct irqaction mct_comp_event_irq = {
+	.name		= "mct_comp_irq",
+	.flags		= IRQF_TIMER | IRQF_IRQPOLL,
+	.handler	= exynos4_mct_comp_isr,
+	.dev_id		= &mct_comp_device,
+};
+
+static int exynos4_clockevent_init(void)
+{
+	mct_comp_device.cpumask = cpumask_of(0);
+	clockevents_config_and_register(&mct_comp_device, clk_rate,
+					0xf, 0xffffffff);
+	setup_irq(mct_irqs[MCT_G0_IRQ], &mct_comp_event_irq);
+
+	return 0;
+}
+
+static DEFINE_PER_CPU(struct mct_clock_event_device, percpu_mct_tick);
+
+/* Clock event handling */
+static void exynos4_mct_tick_stop(struct mct_clock_event_device *mevt)
+{
+	unsigned long tmp;
+	unsigned long mask = MCT_L_TCON_INT_START | MCT_L_TCON_TIMER_START;
+	unsigned long offset = mevt->base + MCT_L_TCON_OFFSET;
+
+	tmp = readl_relaxed(reg_base + offset);
+	if (tmp & mask) {
+		tmp &= ~mask;
+		exynos4_mct_write(tmp, offset);
+	}
+}
+
+static void exynos4_mct_tick_start(unsigned long cycles,
+				   struct mct_clock_event_device *mevt)
+{
+	unsigned long tmp;
+
+	exynos4_mct_tick_stop(mevt);
+
+	tmp = (1 << 31) | cycles;	/* MCT_L_UPDATE_ICNTB */
+
+	/* update interrupt count buffer */
+	exynos4_mct_write(tmp, mevt->base + MCT_L_ICNTB_OFFSET);
+
+	/* enable MCT tick interrupt */
+	exynos4_mct_write(0x1, mevt->base + MCT_L_INT_ENB_OFFSET);
+
+	tmp = readl_relaxed(reg_base + mevt->base + MCT_L_TCON_OFFSET);
+	tmp |= MCT_L_TCON_INT_START | MCT_L_TCON_TIMER_START |
+	       MCT_L_TCON_INTERVAL_MODE;
+	exynos4_mct_write(tmp, mevt->base + MCT_L_TCON_OFFSET);
+}
+
+static void exynos4_mct_tick_clear(struct mct_clock_event_device *mevt)
+{
+	/* Clear the MCT tick interrupt */
+	if (readl_relaxed(reg_base + mevt->base + MCT_L_INT_CSTAT_OFFSET) & 1)
+		exynos4_mct_write(0x1, mevt->base + MCT_L_INT_CSTAT_OFFSET);
+}
+
+static int exynos4_tick_set_next_event(unsigned long cycles,
+				       struct clock_event_device *evt)
+{
+	struct mct_clock_event_device *mevt;
+
+	mevt = container_of(evt, struct mct_clock_event_device, evt);
+	exynos4_mct_tick_start(cycles, mevt);
+	return 0;
+}
+
+static int set_state_shutdown(struct clock_event_device *evt)
+{
+	struct mct_clock_event_device *mevt;
+
+	mevt = container_of(evt, struct mct_clock_event_device, evt);
+	exynos4_mct_tick_stop(mevt);
+	exynos4_mct_tick_clear(mevt);
+	return 0;
+}
+
+static int set_state_periodic(struct clock_event_device *evt)
+{
+	struct mct_clock_event_device *mevt;
+	unsigned long cycles_per_jiffy;
+
+	mevt = container_of(evt, struct mct_clock_event_device, evt);
+	cycles_per_jiffy = (((unsigned long long)NSEC_PER_SEC / HZ * evt->mult)
+			    >> evt->shift);
+	exynos4_mct_tick_stop(mevt);
+	exynos4_mct_tick_start(cycles_per_jiffy, mevt);
+	return 0;
+}
+
+static irqreturn_t exynos4_mct_tick_isr(int irq, void *dev_id)
+{
+	struct mct_clock_event_device *mevt = dev_id;
+	struct clock_event_device *evt = &mevt->evt;
+
+	/*
+	 * This is for supporting oneshot mode.
+	 * Mct would generate interrupt periodically
+	 * without explicit stopping.
+	 */
+	if (!clockevent_state_periodic(&mevt->evt))
+		exynos4_mct_tick_stop(mevt);
+
+	exynos4_mct_tick_clear(mevt);
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static int exynos4_mct_starting_cpu(unsigned int cpu)
+{
+	struct mct_clock_event_device *mevt =
+		per_cpu_ptr(&percpu_mct_tick, cpu);
+	struct clock_event_device *evt = &mevt->evt;
+
+	mevt->base = EXYNOS4_MCT_L_BASE(cpu);
+	snprintf(mevt->name, sizeof(mevt->name), "mct_tick%d", cpu);
+
+	evt->name = mevt->name;
+	evt->cpumask = cpumask_of(cpu);
+	evt->set_next_event = exynos4_tick_set_next_event;
+	evt->set_state_periodic = set_state_periodic;
+	evt->set_state_shutdown = set_state_shutdown;
+	evt->set_state_oneshot = set_state_shutdown;
+	evt->set_state_oneshot_stopped = set_state_shutdown;
+	evt->tick_resume = set_state_shutdown;
+	evt->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
+	evt->rating = 500;	/* use value higher than ARM arch timer */
+
+	exynos4_mct_write(TICK_BASE_CNT, mevt->base + MCT_L_TCNTB_OFFSET);
+
+	if (mct_int_type == MCT_INT_SPI) {
+
+		if (evt->irq == -1)
+			return -EIO;
+
+		irq_force_affinity(evt->irq, cpumask_of(cpu));
+		enable_irq(evt->irq);
+	} else {
+		enable_percpu_irq(mct_irqs[MCT_L0_IRQ], 0);
+	}
+	clockevents_config_and_register(evt, clk_rate / (TICK_BASE_CNT + 1),
+					0xf, 0x7fffffff);
+
+	return 0;
+}
+
+static int exynos4_mct_dying_cpu(unsigned int cpu)
+{
+	struct mct_clock_event_device *mevt =
+		per_cpu_ptr(&percpu_mct_tick, cpu);
+	struct clock_event_device *evt = &mevt->evt;
+
+	evt->set_state_shutdown(evt);
+	if (mct_int_type == MCT_INT_SPI) {
+		if (evt->irq != -1)
+			disable_irq_nosync(evt->irq);
+		exynos4_mct_write(0x1, mevt->base + MCT_L_INT_CSTAT_OFFSET);
+	} else {
+		disable_percpu_irq(mct_irqs[MCT_L0_IRQ]);
+	}
+	return 0;
+}
+
+static int __init exynos4_timer_resources(struct device_node *np, void __iomem *base)
+{
+	int err, cpu;
+	struct clk *mct_clk, *tick_clk;
+
+	tick_clk = np ? of_clk_get_by_name(np, "fin_pll") :
+				clk_get(NULL, "fin_pll");
+	if (IS_ERR(tick_clk))
+		panic("%s: unable to determine tick clock rate\n", __func__);
+	clk_rate = clk_get_rate(tick_clk);
+
+	mct_clk = np ? of_clk_get_by_name(np, "mct") : clk_get(NULL, "mct");
+	if (IS_ERR(mct_clk))
+		panic("%s: unable to retrieve mct clock instance\n", __func__);
+	clk_prepare_enable(mct_clk);
+
+	reg_base = base;
+	if (!reg_base)
+		panic("%s: unable to ioremap mct address space\n", __func__);
+
+	if (mct_int_type == MCT_INT_PPI) {
+
+		err = request_percpu_irq(mct_irqs[MCT_L0_IRQ],
+					 exynos4_mct_tick_isr, "MCT",
+					 &percpu_mct_tick);
+		WARN(err, "MCT: can't request IRQ %d (%d)\n",
+		     mct_irqs[MCT_L0_IRQ], err);
+	} else {
+		for_each_possible_cpu(cpu) {
+			int mct_irq = mct_irqs[MCT_L0_IRQ + cpu];
+			struct mct_clock_event_device *pcpu_mevt =
+				per_cpu_ptr(&percpu_mct_tick, cpu);
+
+			pcpu_mevt->evt.irq = -1;
+
+			irq_set_status_flags(mct_irq, IRQ_NOAUTOEN);
+			if (request_irq(mct_irq,
+					exynos4_mct_tick_isr,
+					IRQF_TIMER | IRQF_NOBALANCING,
+					pcpu_mevt->name, pcpu_mevt)) {
+				pr_err("exynos-mct: cannot register IRQ (cpu%d)\n",
+									cpu);
+
+				continue;
+			}
+			pcpu_mevt->evt.irq = mct_irq;
+		}
+	}
+
+	/* Install hotplug callbacks which configure the timer on this CPU */
+	err = cpuhp_setup_state(CPUHP_AP_EXYNOS4_MCT_TIMER_STARTING,
+				"clockevents/exynos4/mct_timer:starting",
+				exynos4_mct_starting_cpu,
+				exynos4_mct_dying_cpu);
+	if (err)
+		goto out_irq;
+
+	return 0;
+
+out_irq:
+	if (mct_int_type == MCT_INT_PPI) {
+		free_percpu_irq(mct_irqs[MCT_L0_IRQ], &percpu_mct_tick);
+	} else {
+		for_each_possible_cpu(cpu) {
+			struct mct_clock_event_device *pcpu_mevt =
+				per_cpu_ptr(&percpu_mct_tick, cpu);
+
+			if (pcpu_mevt->evt.irq != -1) {
+				free_irq(pcpu_mevt->evt.irq, pcpu_mevt);
+				pcpu_mevt->evt.irq = -1;
+			}
+		}
+	}
+	return err;
+}
+
+static int __init mct_init_dt(struct device_node *np, unsigned int int_type)
+{
+	u32 nr_irqs, i;
+	int ret;
+
+	mct_int_type = int_type;
+
+	/* This driver uses only one global timer interrupt */
+	mct_irqs[MCT_G0_IRQ] = irq_of_parse_and_map(np, MCT_G0_IRQ);
+
+	/*
+	 * Find out the number of local irqs specified. The local
+	 * timer irqs are specified after the four global timer
+	 * irqs are specified.
+	 */
+#ifdef CONFIG_OF
+	nr_irqs = of_irq_count(np);
+#else
+	nr_irqs = 0;
+#endif
+	for (i = MCT_L0_IRQ; i < nr_irqs; i++)
+		mct_irqs[i] = irq_of_parse_and_map(np, i);
+
+	ret = exynos4_timer_resources(np, of_iomap(np, 0));
+	if (ret)
+		return ret;
+
+	ret = exynos4_clocksource_init();
+	if (ret)
+		return ret;
+
+	return exynos4_clockevent_init();
+}
+
+
+static int __init mct_init_spi(struct device_node *np)
+{
+	return mct_init_dt(np, MCT_INT_SPI);
+}
+
+static int __init mct_init_ppi(struct device_node *np)
+{
+	return mct_init_dt(np, MCT_INT_PPI);
+}
+TIMER_OF_DECLARE(exynos4210, "samsung,exynos4210-mct", mct_init_spi);
+TIMER_OF_DECLARE(exynos4412, "samsung,exynos4412-mct", mct_init_ppi);

drivers/clocksource/fsl_ftm_timer.c

@@ -0,0 +1,376 @@
+/*
+ * Freescale FlexTimer Module (FTM) timer driver.
+ *
+ * Copyright 2014 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ */
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+#include <linux/slab.h>
+
+#define FTM_SC		0x00
+#define FTM_SC_CLK_SHIFT	3
+#define FTM_SC_CLK_MASK	(0x3 << FTM_SC_CLK_SHIFT)
+#define FTM_SC_CLK(c)	((c) << FTM_SC_CLK_SHIFT)
+#define FTM_SC_PS_MASK	0x7
+#define FTM_SC_TOIE	BIT(6)
+#define FTM_SC_TOF	BIT(7)
+
+#define FTM_CNT		0x04
+#define FTM_MOD		0x08
+#define FTM_CNTIN	0x4C
+
+#define FTM_PS_MAX	7
+
+struct ftm_clock_device {
+	void __iomem *clksrc_base;
+	void __iomem *clkevt_base;
+	unsigned long periodic_cyc;
+	unsigned long ps;
+	bool big_endian;
+};
+
+static struct ftm_clock_device *priv;
+
+static inline u32 ftm_readl(void __iomem *addr)
+{
+	if (priv->big_endian)
+		return ioread32be(addr);
+	else
+		return ioread32(addr);
+}
+
+static inline void ftm_writel(u32 val, void __iomem *addr)
+{
+	if (priv->big_endian)
+		iowrite32be(val, addr);
+	else
+		iowrite32(val, addr);
+}
+
+static inline void ftm_counter_enable(void __iomem *base)
+{
+	u32 val;
+
+	/* select and enable counter clock source */
+	val = ftm_readl(base + FTM_SC);
+	val &= ~(FTM_SC_PS_MASK | FTM_SC_CLK_MASK);
+	val |= priv->ps | FTM_SC_CLK(1);
+	ftm_writel(val, base + FTM_SC);
+}
+
+static inline void ftm_counter_disable(void __iomem *base)
+{
+	u32 val;
+
+	/* disable counter clock source */
+	val = ftm_readl(base + FTM_SC);
+	val &= ~(FTM_SC_PS_MASK | FTM_SC_CLK_MASK);
+	ftm_writel(val, base + FTM_SC);
+}
+
+static inline void ftm_irq_acknowledge(void __iomem *base)
+{
+	u32 val;
+
+	val = ftm_readl(base + FTM_SC);
+	val &= ~FTM_SC_TOF;
+	ftm_writel(val, base + FTM_SC);
+}
+
+static inline void ftm_irq_enable(void __iomem *base)
+{
+	u32 val;
+
+	val = ftm_readl(base + FTM_SC);
+	val |= FTM_SC_TOIE;
+	ftm_writel(val, base + FTM_SC);
+}
+
+static inline void ftm_irq_disable(void __iomem *base)
+{
+	u32 val;
+
+	val = ftm_readl(base + FTM_SC);
+	val &= ~FTM_SC_TOIE;
+	ftm_writel(val, base + FTM_SC);
+}
+
+static inline void ftm_reset_counter(void __iomem *base)
+{
+	/*
+	 * The CNT register contains the FTM counter value.
+	 * Reset clears the CNT register. Writing any value to COUNT
+	 * updates the counter with its initial value, CNTIN.
+	 */
+	ftm_writel(0x00, base + FTM_CNT);
+}
+
+static u64 notrace ftm_read_sched_clock(void)
+{
+	return ftm_readl(priv->clksrc_base + FTM_CNT);
+}
+
+static int ftm_set_next_event(unsigned long delta,
+				struct clock_event_device *unused)
+{
+	/*
+	 * The CNNIN and MOD are all double buffer registers, writing
+	 * to the MOD register latches the value into a buffer. The MOD
+	 * register is updated with the value of its write buffer with
+	 * the following scenario:
+	 * a, the counter source clock is diabled.
+	 */
+	ftm_counter_disable(priv->clkevt_base);
+
+	/* Force the value of CNTIN to be loaded into the FTM counter */
+	ftm_reset_counter(priv->clkevt_base);
+
+	/*
+	 * The counter increments until the value of MOD is reached,
+	 * at which point the counter is reloaded with the value of CNTIN.
+	 * The TOF (the overflow flag) bit is set when the FTM counter
+	 * changes from MOD to CNTIN. So we should using the delta - 1.
+	 */
+	ftm_writel(delta - 1, priv->clkevt_base + FTM_MOD);
+
+	ftm_counter_enable(priv->clkevt_base);
+
+	ftm_irq_enable(priv->clkevt_base);
+
+	return 0;
+}
+
+static int ftm_set_oneshot(struct clock_event_device *evt)
+{
+	ftm_counter_disable(priv->clkevt_base);
+	return 0;
+}
+
+static int ftm_set_periodic(struct clock_event_device *evt)
+{
+	ftm_set_next_event(priv->periodic_cyc, evt);
+	return 0;
+}
+
+static irqreturn_t ftm_evt_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	ftm_irq_acknowledge(priv->clkevt_base);
+
+	if (likely(clockevent_state_oneshot(evt))) {
+		ftm_irq_disable(priv->clkevt_base);
+		ftm_counter_disable(priv->clkevt_base);
+	}
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static struct clock_event_device ftm_clockevent = {
+	.name			= "Freescale ftm timer",
+	.features		= CLOCK_EVT_FEAT_PERIODIC |
+				  CLOCK_EVT_FEAT_ONESHOT,
+	.set_state_periodic	= ftm_set_periodic,
+	.set_state_oneshot	= ftm_set_oneshot,
+	.set_next_event		= ftm_set_next_event,
+	.rating			= 300,
+};
+
+static struct irqaction ftm_timer_irq = {
+	.name		= "Freescale ftm timer",
+	.flags		= IRQF_TIMER | IRQF_IRQPOLL,
+	.handler	= ftm_evt_interrupt,
+	.dev_id		= &ftm_clockevent,
+};
+
+static int __init ftm_clockevent_init(unsigned long freq, int irq)
+{
+	int err;
+
+	ftm_writel(0x00, priv->clkevt_base + FTM_CNTIN);
+	ftm_writel(~0u, priv->clkevt_base + FTM_MOD);
+
+	ftm_reset_counter(priv->clkevt_base);
+
+	err = setup_irq(irq, &ftm_timer_irq);
+	if (err) {
+		pr_err("ftm: setup irq failed: %d\n", err);
+		return err;
+	}
+
+	ftm_clockevent.cpumask = cpumask_of(0);
+	ftm_clockevent.irq = irq;
+
+	clockevents_config_and_register(&ftm_clockevent,
+					freq / (1 << priv->ps),
+					1, 0xffff);
+
+	ftm_counter_enable(priv->clkevt_base);
+
+	return 0;
+}
+
+static int __init ftm_clocksource_init(unsigned long freq)
+{
+	int err;
+
+	ftm_writel(0x00, priv->clksrc_base + FTM_CNTIN);
+	ftm_writel(~0u, priv->clksrc_base + FTM_MOD);
+
+	ftm_reset_counter(priv->clksrc_base);
+
+	sched_clock_register(ftm_read_sched_clock, 16, freq / (1 << priv->ps));
+	err = clocksource_mmio_init(priv->clksrc_base + FTM_CNT, "fsl-ftm",
+				    freq / (1 << priv->ps), 300, 16,
+				    clocksource_mmio_readl_up);
+	if (err) {
+		pr_err("ftm: init clock source mmio failed: %d\n", err);
+		return err;
+	}
+
+	ftm_counter_enable(priv->clksrc_base);
+
+	return 0;
+}
+
+static int __init __ftm_clk_init(struct device_node *np, char *cnt_name,
+				 char *ftm_name)
+{
+	struct clk *clk;
+	int err;
+
+	clk = of_clk_get_by_name(np, cnt_name);
+	if (IS_ERR(clk)) {
+		pr_err("ftm: Cannot get \"%s\": %ld\n", cnt_name, PTR_ERR(clk));
+		return PTR_ERR(clk);
+	}
+	err = clk_prepare_enable(clk);
+	if (err) {
+		pr_err("ftm: clock failed to prepare+enable \"%s\": %d\n",
+			cnt_name, err);
+		return err;
+	}
+
+	clk = of_clk_get_by_name(np, ftm_name);
+	if (IS_ERR(clk)) {
+		pr_err("ftm: Cannot get \"%s\": %ld\n", ftm_name, PTR_ERR(clk));
+		return PTR_ERR(clk);
+	}
+	err = clk_prepare_enable(clk);
+	if (err)
+		pr_err("ftm: clock failed to prepare+enable \"%s\": %d\n",
+			ftm_name, err);
+
+	return clk_get_rate(clk);
+}
+
+static unsigned long __init ftm_clk_init(struct device_node *np)
+{
+	long freq;
+
+	freq = __ftm_clk_init(np, "ftm-evt-counter-en", "ftm-evt");
+	if (freq <= 0)
+		return 0;
+
+	freq = __ftm_clk_init(np, "ftm-src-counter-en", "ftm-src");
+	if (freq <= 0)
+		return 0;
+
+	return freq;
+}
+
+static int __init ftm_calc_closest_round_cyc(unsigned long freq)
+{
+	priv->ps = 0;
+
+	/* The counter register is only using the lower 16 bits, and
+	 * if the 'freq' value is to big here, then the periodic_cyc
+	 * may exceed 0xFFFF.
+	 */
+	do {
+		priv->periodic_cyc = DIV_ROUND_CLOSEST(freq,
+						HZ * (1 << priv->ps++));
+	} while (priv->periodic_cyc > 0xFFFF);
+
+	if (priv->ps > FTM_PS_MAX) {
+		pr_err("ftm: the prescaler is %lu > %d\n",
+				priv->ps, FTM_PS_MAX);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int __init ftm_timer_init(struct device_node *np)
+{
+	unsigned long freq;
+	int ret, irq;
+
+	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	ret = -ENXIO;
+	priv->clkevt_base = of_iomap(np, 0);
+	if (!priv->clkevt_base) {
+		pr_err("ftm: unable to map event timer registers\n");
+		goto err_clkevt;
+	}
+
+	priv->clksrc_base = of_iomap(np, 1);
+	if (!priv->clksrc_base) {
+		pr_err("ftm: unable to map source timer registers\n");
+		goto err_clksrc;
+	}
+
+	ret = -EINVAL;
+	irq = irq_of_parse_and_map(np, 0);
+	if (irq <= 0) {
+		pr_err("ftm: unable to get IRQ from DT, %d\n", irq);
+		goto err;
+	}
+
+	priv->big_endian = of_property_read_bool(np, "big-endian");
+
+	freq = ftm_clk_init(np);
+	if (!freq)
+		goto err;
+
+	ret = ftm_calc_closest_round_cyc(freq);
+	if (ret)
+		goto err;
+
+	ret = ftm_clocksource_init(freq);
+	if (ret)
+		goto err;
+
+	ret = ftm_clockevent_init(freq, irq);
+	if (ret)
+		goto err;
+
+	return 0;
+
+err:
+	iounmap(priv->clksrc_base);
+err_clksrc:
+	iounmap(priv->clkevt_base);
+err_clkevt:
+	kfree(priv);
+	return ret;
+}
+TIMER_OF_DECLARE(flextimer, "fsl,ftm-timer", ftm_timer_init);

drivers/clocksource/h8300_timer16.c

@@ -0,0 +1,192 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  H8/300 16bit Timer driver
+ *
+ *  Copyright 2015 Yoshinori Sato <ysato@users.sourcefoge.jp>
+ */
+
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/clocksource.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define TSTR	0
+#define TISRC	6
+
+#define TCR	0
+#define TCNT	2
+
+#define bset(b, a) iowrite8(ioread8(a) | (1 << (b)), (a))
+#define bclr(b, a) iowrite8(ioread8(a) & ~(1 << (b)), (a))
+
+struct timer16_priv {
+	struct clocksource cs;
+	unsigned long total_cycles;
+	void __iomem *mapbase;
+	void __iomem *mapcommon;
+	unsigned short cs_enabled;
+	unsigned char enb;
+	unsigned char ovf;
+	unsigned char ovie;
+};
+
+static unsigned long timer16_get_counter(struct timer16_priv *p)
+{
+	unsigned short v1, v2, v3;
+	unsigned char  o1, o2;
+
+	o1 = ioread8(p->mapcommon + TISRC) & p->ovf;
+
+	/* Make sure the timer value is stable. Stolen from acpi_pm.c */
+	do {
+		o2 = o1;
+		v1 = ioread16be(p->mapbase + TCNT);
+		v2 = ioread16be(p->mapbase + TCNT);
+		v3 = ioread16be(p->mapbase + TCNT);
+		o1 = ioread8(p->mapcommon + TISRC) & p->ovf;
+	} while (unlikely((o1 != o2) || (v1 > v2 && v1 < v3)
+			  || (v2 > v3 && v2 < v1) || (v3 > v1 && v3 < v2)));
+
+	if (likely(!o1))
+		return v2;
+	else
+		return v2 + 0x10000;
+}
+
+
+static irqreturn_t timer16_interrupt(int irq, void *dev_id)
+{
+	struct timer16_priv *p = (struct timer16_priv *)dev_id;
+
+	bclr(p->ovf, p->mapcommon + TISRC);
+	p->total_cycles += 0x10000;
+
+	return IRQ_HANDLED;
+}
+
+static inline struct timer16_priv *cs_to_priv(struct clocksource *cs)
+{
+	return container_of(cs, struct timer16_priv, cs);
+}
+
+static u64 timer16_clocksource_read(struct clocksource *cs)
+{
+	struct timer16_priv *p = cs_to_priv(cs);
+	unsigned long raw, value;
+
+	value = p->total_cycles;
+	raw = timer16_get_counter(p);
+
+	return value + raw;
+}
+
+static int timer16_enable(struct clocksource *cs)
+{
+	struct timer16_priv *p = cs_to_priv(cs);
+
+	WARN_ON(p->cs_enabled);
+
+	p->total_cycles = 0;
+	iowrite16be(0x0000, p->mapbase + TCNT);
+	iowrite8(0x83, p->mapbase + TCR);
+	bset(p->ovie, p->mapcommon + TISRC);
+	bset(p->enb, p->mapcommon + TSTR);
+
+	p->cs_enabled = true;
+	return 0;
+}
+
+static void timer16_disable(struct clocksource *cs)
+{
+	struct timer16_priv *p = cs_to_priv(cs);
+
+	WARN_ON(!p->cs_enabled);
+
+	bclr(p->ovie, p->mapcommon + TISRC);
+	bclr(p->enb, p->mapcommon + TSTR);
+
+	p->cs_enabled = false;
+}
+
+static struct timer16_priv timer16_priv = {
+	.cs = {
+		.name = "h8300_16timer",
+		.rating = 200,
+		.read = timer16_clocksource_read,
+		.enable = timer16_enable,
+		.disable = timer16_disable,
+		.mask = CLOCKSOURCE_MASK(sizeof(unsigned long) * 8),
+		.flags = CLOCK_SOURCE_IS_CONTINUOUS,
+	},
+};
+
+#define REG_CH   0
+#define REG_COMM 1
+
+static int __init h8300_16timer_init(struct device_node *node)
+{
+	void __iomem *base[2];
+	int ret, irq;
+	unsigned int ch;
+	struct clk *clk;
+
+	clk = of_clk_get(node, 0);
+	if (IS_ERR(clk)) {
+		pr_err("failed to get clock for clocksource\n");
+		return PTR_ERR(clk);
+	}
+
+	ret = -ENXIO;
+	base[REG_CH] = of_iomap(node, 0);
+	if (!base[REG_CH]) {
+		pr_err("failed to map registers for clocksource\n");
+		goto free_clk;
+	}
+
+	base[REG_COMM] = of_iomap(node, 1);
+	if (!base[REG_COMM]) {
+		pr_err("failed to map registers for clocksource\n");
+		goto unmap_ch;
+	}
+
+	ret = -EINVAL;
+	irq = irq_of_parse_and_map(node, 0);
+	if (!irq) {
+		pr_err("failed to get irq for clockevent\n");
+		goto unmap_comm;
+	}
+
+	of_property_read_u32(node, "renesas,channel", &ch);
+
+	timer16_priv.mapbase = base[REG_CH];
+	timer16_priv.mapcommon = base[REG_COMM];
+	timer16_priv.enb = ch;
+	timer16_priv.ovf = ch;
+	timer16_priv.ovie = 4 + ch;
+
+	ret = request_irq(irq, timer16_interrupt,
+			  IRQF_TIMER, timer16_priv.cs.name, &timer16_priv);
+	if (ret < 0) {
+		pr_err("failed to request irq %d of clocksource\n", irq);
+		goto unmap_comm;
+	}
+
+	clocksource_register_hz(&timer16_priv.cs,
+				clk_get_rate(clk) / 8);
+	return 0;
+
+unmap_comm:
+	iounmap(base[REG_COMM]);
+unmap_ch:
+	iounmap(base[REG_CH]);
+free_clk:
+	clk_put(clk);
+	return ret;
+}
+
+TIMER_OF_DECLARE(h8300_16bit, "renesas,16bit-timer",
+			   h8300_16timer_init);

drivers/clocksource/h8300_timer8.c

@@ -0,0 +1,211 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  linux/arch/h8300/kernel/cpu/timer/timer8.c
+ *
+ *  Yoshinori Sato <ysato@users.sourcefoge.jp>
+ *
+ *  8bit Timer driver
+ *
+ */
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/init.h>
+#include <linux/clockchips.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define _8TCR	0
+#define _8TCSR	2
+#define TCORA	4
+#define TCORB	6
+#define _8TCNT	8
+
+#define CMIEA	6
+#define CMFA	6
+
+#define FLAG_STARTED (1 << 3)
+
+#define SCALE 64
+
+#define bset(b, a) iowrite8(ioread8(a) | (1 << (b)), (a))
+#define bclr(b, a) iowrite8(ioread8(a) & ~(1 << (b)), (a))
+
+struct timer8_priv {
+	struct clock_event_device ced;
+	void __iomem *mapbase;
+	unsigned long flags;
+	unsigned int rate;
+};
+
+static irqreturn_t timer8_interrupt(int irq, void *dev_id)
+{
+	struct timer8_priv *p = dev_id;
+
+	if (clockevent_state_oneshot(&p->ced))
+		iowrite16be(0x0000, p->mapbase + _8TCR);
+
+	p->ced.event_handler(&p->ced);
+
+	bclr(CMFA, p->mapbase + _8TCSR);
+
+	return IRQ_HANDLED;
+}
+
+static void timer8_set_next(struct timer8_priv *p, unsigned long delta)
+{
+	if (delta >= 0x10000)
+		pr_warn("delta out of range\n");
+	bclr(CMIEA, p->mapbase + _8TCR);
+	iowrite16be(delta, p->mapbase + TCORA);
+	iowrite16be(0x0000, p->mapbase + _8TCNT);
+	bclr(CMFA, p->mapbase + _8TCSR);
+	bset(CMIEA, p->mapbase + _8TCR);
+}
+
+static int timer8_enable(struct timer8_priv *p)
+{
+	iowrite16be(0xffff, p->mapbase + TCORA);
+	iowrite16be(0x0000, p->mapbase + _8TCNT);
+	iowrite16be(0x0c02, p->mapbase + _8TCR);
+
+	return 0;
+}
+
+static int timer8_start(struct timer8_priv *p)
+{
+	int ret;
+
+	if ((p->flags & FLAG_STARTED))
+		return 0;
+
+	ret = timer8_enable(p);
+	if (!ret)
+		p->flags |= FLAG_STARTED;
+
+	return ret;
+}
+
+static void timer8_stop(struct timer8_priv *p)
+{
+	iowrite16be(0x0000, p->mapbase + _8TCR);
+}
+
+static inline struct timer8_priv *ced_to_priv(struct clock_event_device *ced)
+{
+	return container_of(ced, struct timer8_priv, ced);
+}
+
+static void timer8_clock_event_start(struct timer8_priv *p, unsigned long delta)
+{
+	timer8_start(p);
+	timer8_set_next(p, delta);
+}
+
+static int timer8_clock_event_shutdown(struct clock_event_device *ced)
+{
+	timer8_stop(ced_to_priv(ced));
+	return 0;
+}
+
+static int timer8_clock_event_periodic(struct clock_event_device *ced)
+{
+	struct timer8_priv *p = ced_to_priv(ced);
+
+	pr_info("%s: used for periodic clock events\n", ced->name);
+	timer8_stop(p);
+	timer8_clock_event_start(p, (p->rate + HZ/2) / HZ);
+
+	return 0;
+}
+
+static int timer8_clock_event_oneshot(struct clock_event_device *ced)
+{
+	struct timer8_priv *p = ced_to_priv(ced);
+
+	pr_info("%s: used for oneshot clock events\n", ced->name);
+	timer8_stop(p);
+	timer8_clock_event_start(p, 0x10000);
+
+	return 0;
+}
+
+static int timer8_clock_event_next(unsigned long delta,
+				   struct clock_event_device *ced)
+{
+	struct timer8_priv *p = ced_to_priv(ced);
+
+	BUG_ON(!clockevent_state_oneshot(ced));
+	timer8_set_next(p, delta - 1);
+
+	return 0;
+}
+
+static struct timer8_priv timer8_priv = {
+	.ced = {
+		.name = "h8300_8timer",
+		.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+		.rating = 200,
+		.set_next_event = timer8_clock_event_next,
+		.set_state_shutdown = timer8_clock_event_shutdown,
+		.set_state_periodic = timer8_clock_event_periodic,
+		.set_state_oneshot = timer8_clock_event_oneshot,
+	},
+};
+
+static int __init h8300_8timer_init(struct device_node *node)
+{
+	void __iomem *base;
+	int irq, ret;
+	struct clk *clk;
+
+	clk = of_clk_get(node, 0);
+	if (IS_ERR(clk)) {
+		pr_err("failed to get clock for clockevent\n");
+		return PTR_ERR(clk);
+	}
+
+	ret = -ENXIO;
+	base = of_iomap(node, 0);
+	if (!base) {
+		pr_err("failed to map registers for clockevent\n");
+		goto free_clk;
+	}
+
+	ret = -EINVAL;
+	irq = irq_of_parse_and_map(node, 0);
+	if (!irq) {
+		pr_err("failed to get irq for clockevent\n");
+		goto unmap_reg;
+	}
+
+	timer8_priv.mapbase = base;
+
+	timer8_priv.rate = clk_get_rate(clk) / SCALE;
+	if (!timer8_priv.rate) {
+		pr_err("Failed to get rate for the clocksource\n");
+		goto unmap_reg;
+	}
+
+	if (request_irq(irq, timer8_interrupt, IRQF_TIMER,
+			timer8_priv.ced.name, &timer8_priv) < 0) {
+		pr_err("failed to request irq %d for clockevent\n", irq);
+		goto unmap_reg;
+	}
+
+	clockevents_config_and_register(&timer8_priv.ced,
+					timer8_priv.rate, 1, 0x0000ffff);
+
+	return 0;
+unmap_reg:
+	iounmap(base);
+free_clk:
+	clk_put(clk);
+	return ret;
+}
+
+TIMER_OF_DECLARE(h8300_8bit, "renesas,8bit-timer", h8300_8timer_init);

drivers/clocksource/h8300_tpu.c

@@ -0,0 +1,158 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  H8S TPU Driver
+ *
+ *  Copyright 2015 Yoshinori Sato <ysato@users.sourcefoge.jp>
+ *
+ */
+
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/clocksource.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define TCR	0x0
+#define TSR	0x5
+#define TCNT	0x6
+
+#define TCFV	0x10
+
+struct tpu_priv {
+	struct clocksource cs;
+	void __iomem *mapbase1;
+	void __iomem *mapbase2;
+	raw_spinlock_t lock;
+	unsigned int cs_enabled;
+};
+
+static inline unsigned long read_tcnt32(struct tpu_priv *p)
+{
+	unsigned long tcnt;
+
+	tcnt = ioread16be(p->mapbase1 + TCNT) << 16;
+	tcnt |= ioread16be(p->mapbase2 + TCNT);
+	return tcnt;
+}
+
+static int tpu_get_counter(struct tpu_priv *p, unsigned long long *val)
+{
+	unsigned long v1, v2, v3;
+	int o1, o2;
+
+	o1 = ioread8(p->mapbase1 + TSR) & TCFV;
+
+	/* Make sure the timer value is stable. Stolen from acpi_pm.c */
+	do {
+		o2 = o1;
+		v1 = read_tcnt32(p);
+		v2 = read_tcnt32(p);
+		v3 = read_tcnt32(p);
+		o1 = ioread8(p->mapbase1 + TSR) & TCFV;
+	} while (unlikely((o1 != o2) || (v1 > v2 && v1 < v3)
+			  || (v2 > v3 && v2 < v1) || (v3 > v1 && v3 < v2)));
+
+	*val = v2;
+	return o1;
+}
+
+static inline struct tpu_priv *cs_to_priv(struct clocksource *cs)
+{
+	return container_of(cs, struct tpu_priv, cs);
+}
+
+static u64 tpu_clocksource_read(struct clocksource *cs)
+{
+	struct tpu_priv *p = cs_to_priv(cs);
+	unsigned long flags;
+	unsigned long long value;
+
+	raw_spin_lock_irqsave(&p->lock, flags);
+	if (tpu_get_counter(p, &value))
+		value += 0x100000000;
+	raw_spin_unlock_irqrestore(&p->lock, flags);
+
+	return value;
+}
+
+static int tpu_clocksource_enable(struct clocksource *cs)
+{
+	struct tpu_priv *p = cs_to_priv(cs);
+
+	WARN_ON(p->cs_enabled);
+
+	iowrite16be(0, p->mapbase1 + TCNT);
+	iowrite16be(0, p->mapbase2 + TCNT);
+	iowrite8(0x0f, p->mapbase1 + TCR);
+	iowrite8(0x03, p->mapbase2 + TCR);
+
+	p->cs_enabled = true;
+	return 0;
+}
+
+static void tpu_clocksource_disable(struct clocksource *cs)
+{
+	struct tpu_priv *p = cs_to_priv(cs);
+
+	WARN_ON(!p->cs_enabled);
+
+	iowrite8(0, p->mapbase1 + TCR);
+	iowrite8(0, p->mapbase2 + TCR);
+	p->cs_enabled = false;
+}
+
+static struct tpu_priv tpu_priv = {
+	.cs = {
+		.name = "H8S_TPU",
+		.rating = 200,
+		.read = tpu_clocksource_read,
+		.enable = tpu_clocksource_enable,
+		.disable = tpu_clocksource_disable,
+		.mask = CLOCKSOURCE_MASK(sizeof(unsigned long) * 8),
+		.flags = CLOCK_SOURCE_IS_CONTINUOUS,
+	},
+};
+
+#define CH_L 0
+#define CH_H 1
+
+static int __init h8300_tpu_init(struct device_node *node)
+{
+	void __iomem *base[2];
+	struct clk *clk;
+	int ret = -ENXIO;
+
+	clk = of_clk_get(node, 0);
+	if (IS_ERR(clk)) {
+		pr_err("failed to get clock for clocksource\n");
+		return PTR_ERR(clk);
+	}
+
+	base[CH_L] = of_iomap(node, CH_L);
+	if (!base[CH_L]) {
+		pr_err("failed to map registers for clocksource\n");
+		goto free_clk;
+	}
+	base[CH_H] = of_iomap(node, CH_H);
+	if (!base[CH_H]) {
+		pr_err("failed to map registers for clocksource\n");
+		goto unmap_L;
+	}
+
+	tpu_priv.mapbase1 = base[CH_L];
+	tpu_priv.mapbase2 = base[CH_H];
+
+	return clocksource_register_hz(&tpu_priv.cs, clk_get_rate(clk) / 64);
+
+unmap_L:
+	iounmap(base[CH_H]);
+free_clk:
+	clk_put(clk);
+	return ret;
+}
+
+TIMER_OF_DECLARE(h8300_tpu, "renesas,tpu", h8300_tpu_init);

drivers/clocksource/i8253.c

@@ -0,0 +1,196 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * i8253 PIT clocksource
+ */
+#include <linux/clockchips.h>
+#include <linux/init.h>
+#include <linux/io.h>
+#include <linux/spinlock.h>
+#include <linux/timex.h>
+#include <linux/module.h>
+#include <linux/i8253.h>
+#include <linux/smp.h>
+
+/*
+ * Protects access to I/O ports
+ *
+ * 0040-0043 : timer0, i8253 / i8254
+ * 0061-0061 : NMI Control Register which contains two speaker control bits.
+ */
+DEFINE_RAW_SPINLOCK(i8253_lock);
+EXPORT_SYMBOL(i8253_lock);
+
+/*
+ * Handle PIT quirk in pit_shutdown() where zeroing the counter register
+ * restarts the PIT, negating the shutdown. On platforms with the quirk,
+ * platform specific code can set this to false.
+ */
+bool i8253_clear_counter_on_shutdown __ro_after_init = true;
+
+#ifdef CONFIG_CLKSRC_I8253
+/*
+ * Since the PIT overflows every tick, its not very useful
+ * to just read by itself. So use jiffies to emulate a free
+ * running counter:
+ */
+static u64 i8253_read(struct clocksource *cs)
+{
+	static int old_count;
+	static u32 old_jifs;
+	unsigned long flags;
+	int count;
+	u32 jifs;
+
+	raw_spin_lock_irqsave(&i8253_lock, flags);
+	/*
+	 * Although our caller may have the read side of jiffies_lock,
+	 * this is now a seqlock, and we are cheating in this routine
+	 * by having side effects on state that we cannot undo if
+	 * there is a collision on the seqlock and our caller has to
+	 * retry.  (Namely, old_jifs and old_count.)  So we must treat
+	 * jiffies as volatile despite the lock.  We read jiffies
+	 * before latching the timer count to guarantee that although
+	 * the jiffies value might be older than the count (that is,
+	 * the counter may underflow between the last point where
+	 * jiffies was incremented and the point where we latch the
+	 * count), it cannot be newer.
+	 */
+	jifs = jiffies;
+	outb_p(0x00, PIT_MODE);	/* latch the count ASAP */
+	count = inb_p(PIT_CH0);	/* read the latched count */
+	count |= inb_p(PIT_CH0) << 8;
+
+	/* VIA686a test code... reset the latch if count > max + 1 */
+	if (count > PIT_LATCH) {
+		outb_p(0x34, PIT_MODE);
+		outb_p(PIT_LATCH & 0xff, PIT_CH0);
+		outb_p(PIT_LATCH >> 8, PIT_CH0);
+		count = PIT_LATCH - 1;
+	}
+
+	/*
+	 * It's possible for count to appear to go the wrong way for a
+	 * couple of reasons:
+	 *
+	 *  1. The timer counter underflows, but we haven't handled the
+	 *     resulting interrupt and incremented jiffies yet.
+	 *  2. Hardware problem with the timer, not giving us continuous time,
+	 *     the counter does small "jumps" upwards on some Pentium systems,
+	 *     (see c't 95/10 page 335 for Neptun bug.)
+	 *
+	 * Previous attempts to handle these cases intelligently were
+	 * buggy, so we just do the simple thing now.
+	 */
+	if (count > old_count && jifs == old_jifs)
+		count = old_count;
+
+	old_count = count;
+	old_jifs = jifs;
+
+	raw_spin_unlock_irqrestore(&i8253_lock, flags);
+
+	count = (PIT_LATCH - 1) - count;
+
+	return (u64)(jifs * PIT_LATCH) + count;
+}
+
+static struct clocksource i8253_cs = {
+	.name		= "pit",
+	.rating		= 110,
+	.read		= i8253_read,
+	.mask		= CLOCKSOURCE_MASK(32),
+};
+
+int __init clocksource_i8253_init(void)
+{
+	return clocksource_register_hz(&i8253_cs, PIT_TICK_RATE);
+}
+#endif
+
+#ifdef CONFIG_CLKEVT_I8253
+static int pit_shutdown(struct clock_event_device *evt)
+{
+	if (!clockevent_state_oneshot(evt) && !clockevent_state_periodic(evt))
+		return 0;
+
+	raw_spin_lock(&i8253_lock);
+
+	outb_p(0x30, PIT_MODE);
+
+	if (i8253_clear_counter_on_shutdown) {
+		outb_p(0, PIT_CH0);
+		outb_p(0, PIT_CH0);
+	}
+
+	raw_spin_unlock(&i8253_lock);
+	return 0;
+}
+
+static int pit_set_oneshot(struct clock_event_device *evt)
+{
+	raw_spin_lock(&i8253_lock);
+	outb_p(0x38, PIT_MODE);
+	raw_spin_unlock(&i8253_lock);
+	return 0;
+}
+
+static int pit_set_periodic(struct clock_event_device *evt)
+{
+	raw_spin_lock(&i8253_lock);
+
+	/* binary, mode 2, LSB/MSB, ch 0 */
+	outb_p(0x34, PIT_MODE);
+	outb_p(PIT_LATCH & 0xff, PIT_CH0);	/* LSB */
+	outb_p(PIT_LATCH >> 8, PIT_CH0);	/* MSB */
+
+	raw_spin_unlock(&i8253_lock);
+	return 0;
+}
+
+/*
+ * Program the next event in oneshot mode
+ *
+ * Delta is given in PIT ticks
+ */
+static int pit_next_event(unsigned long delta, struct clock_event_device *evt)
+{
+	raw_spin_lock(&i8253_lock);
+	outb_p(delta & 0xff , PIT_CH0);	/* LSB */
+	outb_p(delta >> 8 , PIT_CH0);		/* MSB */
+	raw_spin_unlock(&i8253_lock);
+
+	return 0;
+}
+
+/*
+ * On UP the PIT can serve all of the possible timer functions. On SMP systems
+ * it can be solely used for the global tick.
+ */
+struct clock_event_device i8253_clockevent = {
+	.name			= "pit",
+	.features		= CLOCK_EVT_FEAT_PERIODIC,
+	.set_state_shutdown	= pit_shutdown,
+	.set_state_periodic	= pit_set_periodic,
+	.set_next_event		= pit_next_event,
+};
+
+/*
+ * Initialize the conversion factor and the min/max deltas of the clock event
+ * structure and register the clock event source with the framework.
+ */
+void __init clockevent_i8253_init(bool oneshot)
+{
+	if (oneshot) {
+		i8253_clockevent.features |= CLOCK_EVT_FEAT_ONESHOT;
+		i8253_clockevent.set_state_oneshot = pit_set_oneshot;
+	}
+	/*
+	 * Start pit with the boot cpu mask. x86 might make it global
+	 * when it is used as broadcast device later.
+	 */
+	i8253_clockevent.cpumask = cpumask_of(smp_processor_id());
+
+	clockevents_config_and_register(&i8253_clockevent, PIT_TICK_RATE,
+					0xF, 0x7FFF);
+}
+#endif

drivers/clocksource/jcore-pit.c

@@ -0,0 +1,249 @@
+/*
+ * J-Core SoC PIT/clocksource driver
+ *
+ * Copyright (C) 2015-2016 Smart Energy Instruments, Inc.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/sched_clock.h>
+#include <linux/cpu.h>
+#include <linux/cpuhotplug.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define PIT_IRQ_SHIFT		12
+#define PIT_PRIO_SHIFT		20
+#define PIT_ENABLE_SHIFT	26
+#define PIT_PRIO_MASK		0xf
+
+#define REG_PITEN		0x00
+#define REG_THROT		0x10
+#define REG_COUNT		0x14
+#define REG_BUSPD		0x18
+#define REG_SECHI		0x20
+#define REG_SECLO		0x24
+#define REG_NSEC		0x28
+
+struct jcore_pit {
+	struct clock_event_device	ced;
+	void __iomem			*base;
+	unsigned long			periodic_delta;
+	u32				enable_val;
+};
+
+static void __iomem *jcore_pit_base;
+static struct jcore_pit __percpu *jcore_pit_percpu;
+
+static notrace u64 jcore_sched_clock_read(void)
+{
+	u32 seclo, nsec, seclo0;
+	__iomem void *base = jcore_pit_base;
+
+	seclo = readl(base + REG_SECLO);
+	do {
+		seclo0 = seclo;
+		nsec  = readl(base + REG_NSEC);
+		seclo = readl(base + REG_SECLO);
+	} while (seclo0 != seclo);
+
+	return seclo * NSEC_PER_SEC + nsec;
+}
+
+static u64 jcore_clocksource_read(struct clocksource *cs)
+{
+	return jcore_sched_clock_read();
+}
+
+static int jcore_pit_disable(struct jcore_pit *pit)
+{
+	writel(0, pit->base + REG_PITEN);
+	return 0;
+}
+
+static int jcore_pit_set(unsigned long delta, struct jcore_pit *pit)
+{
+	jcore_pit_disable(pit);
+	writel(delta, pit->base + REG_THROT);
+	writel(pit->enable_val, pit->base + REG_PITEN);
+	return 0;
+}
+
+static int jcore_pit_set_state_shutdown(struct clock_event_device *ced)
+{
+	struct jcore_pit *pit = container_of(ced, struct jcore_pit, ced);
+
+	return jcore_pit_disable(pit);
+}
+
+static int jcore_pit_set_state_oneshot(struct clock_event_device *ced)
+{
+	struct jcore_pit *pit = container_of(ced, struct jcore_pit, ced);
+
+	return jcore_pit_disable(pit);
+}
+
+static int jcore_pit_set_state_periodic(struct clock_event_device *ced)
+{
+	struct jcore_pit *pit = container_of(ced, struct jcore_pit, ced);
+
+	return jcore_pit_set(pit->periodic_delta, pit);
+}
+
+static int jcore_pit_set_next_event(unsigned long delta,
+				    struct clock_event_device *ced)
+{
+	struct jcore_pit *pit = container_of(ced, struct jcore_pit, ced);
+
+	return jcore_pit_set(delta, pit);
+}
+
+static int jcore_pit_local_init(unsigned cpu)
+{
+	struct jcore_pit *pit = this_cpu_ptr(jcore_pit_percpu);
+	unsigned buspd, freq;
+
+	pr_info("Local J-Core PIT init on cpu %u\n", cpu);
+
+	buspd = readl(pit->base + REG_BUSPD);
+	freq = DIV_ROUND_CLOSEST(NSEC_PER_SEC, buspd);
+	pit->periodic_delta = DIV_ROUND_CLOSEST(NSEC_PER_SEC, HZ * buspd);
+
+	clockevents_config_and_register(&pit->ced, freq, 1, ULONG_MAX);
+
+	return 0;
+}
+
+static irqreturn_t jcore_timer_interrupt(int irq, void *dev_id)
+{
+	struct jcore_pit *pit = this_cpu_ptr(dev_id);
+
+	if (clockevent_state_oneshot(&pit->ced))
+		jcore_pit_disable(pit);
+
+	pit->ced.event_handler(&pit->ced);
+
+	return IRQ_HANDLED;
+}
+
+static int __init jcore_pit_init(struct device_node *node)
+{
+	int err;
+	unsigned pit_irq, cpu;
+	unsigned long hwirq;
+	u32 irqprio, enable_val;
+
+	jcore_pit_base = of_iomap(node, 0);
+	if (!jcore_pit_base) {
+		pr_err("Error: Cannot map base address for J-Core PIT\n");
+		return -ENXIO;
+	}
+
+	pit_irq = irq_of_parse_and_map(node, 0);
+	if (!pit_irq) {
+		pr_err("Error: J-Core PIT has no IRQ\n");
+		return -ENXIO;
+	}
+
+	pr_info("Initializing J-Core PIT at %p IRQ %d\n",
+		jcore_pit_base, pit_irq);
+
+	err = clocksource_mmio_init(jcore_pit_base, "jcore_pit_cs",
+				    NSEC_PER_SEC, 400, 32,
+				    jcore_clocksource_read);
+	if (err) {
+		pr_err("Error registering clocksource device: %d\n", err);
+		return err;
+	}
+
+	sched_clock_register(jcore_sched_clock_read, 32, NSEC_PER_SEC);
+
+	jcore_pit_percpu = alloc_percpu(struct jcore_pit);
+	if (!jcore_pit_percpu) {
+		pr_err("Failed to allocate memory for clock event device\n");
+		return -ENOMEM;
+	}
+
+	err = request_irq(pit_irq, jcore_timer_interrupt,
+			  IRQF_TIMER | IRQF_PERCPU,
+			  "jcore_pit", jcore_pit_percpu);
+	if (err) {
+		pr_err("pit irq request failed: %d\n", err);
+		free_percpu(jcore_pit_percpu);
+		return err;
+	}
+
+	/*
+	 * The J-Core PIT is not hard-wired to a particular IRQ, but
+	 * integrated with the interrupt controller such that the IRQ it
+	 * generates is programmable, as follows:
+	 *
+	 * The bit layout of the PIT enable register is:
+	 *
+	 *	.....e..ppppiiiiiiii............
+	 *
+	 * where the .'s indicate unrelated/unused bits, e is enable,
+	 * p is priority, and i is hard irq number.
+	 *
+	 * For the PIT included in AIC1 (obsolete but still in use),
+	 * any hard irq (trap number) can be programmed via the 8
+	 * iiiiiiii bits, and a priority (0-15) is programmable
+	 * separately in the pppp bits.
+	 *
+	 * For the PIT included in AIC2 (current), the programming
+	 * interface is equivalent modulo interrupt mapping. This is
+	 * why a different compatible tag was not used. However only
+	 * traps 64-127 (the ones actually intended to be used for
+	 * interrupts, rather than syscalls/exceptions/etc.) can be
+	 * programmed (the high 2 bits of i are ignored) and the
+	 * priority pppp is <<2'd and or'd onto the irq number. This
+	 * choice seems to have been made on the hardware engineering
+	 * side under an assumption that preserving old AIC1 priority
+	 * mappings was important. Future models will likely ignore
+	 * the pppp field.
+	 */
+	hwirq = irq_get_irq_data(pit_irq)->hwirq;
+	irqprio = (hwirq >> 2) & PIT_PRIO_MASK;
+	enable_val = (1U << PIT_ENABLE_SHIFT)
+		   | (hwirq << PIT_IRQ_SHIFT)
+		   | (irqprio << PIT_PRIO_SHIFT);
+
+	for_each_present_cpu(cpu) {
+		struct jcore_pit *pit = per_cpu_ptr(jcore_pit_percpu, cpu);
+
+		pit->base = of_iomap(node, cpu);
+		if (!pit->base) {
+			pr_err("Unable to map PIT for cpu %u\n", cpu);
+			continue;
+		}
+
+		pit->ced.name = "jcore_pit";
+		pit->ced.features = CLOCK_EVT_FEAT_PERIODIC
+				  | CLOCK_EVT_FEAT_ONESHOT
+				  | CLOCK_EVT_FEAT_PERCPU;
+		pit->ced.cpumask = cpumask_of(cpu);
+		pit->ced.rating = 400;
+		pit->ced.irq = pit_irq;
+		pit->ced.set_state_shutdown = jcore_pit_set_state_shutdown;
+		pit->ced.set_state_periodic = jcore_pit_set_state_periodic;
+		pit->ced.set_state_oneshot = jcore_pit_set_state_oneshot;
+		pit->ced.set_next_event = jcore_pit_set_next_event;
+
+		pit->enable_val = enable_val;
+	}
+
+	cpuhp_setup_state(CPUHP_AP_JCORE_TIMER_STARTING,
+			  "clockevents/jcore:starting",
+			  jcore_pit_local_init, NULL);
+
+	return 0;
+}
+
+TIMER_OF_DECLARE(jcore_pit, "jcore,pit", jcore_pit_init);

drivers/clocksource/meson6_timer.c

@@ -0,0 +1,178 @@
+/*
+ * Amlogic Meson6 SoCs timer handling.
+ *
+ * Copyright (C) 2014 Carlo Caione <carlo@caione.org>
+ *
+ * Based on code from Amlogic, Inc
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqreturn.h>
+#include <linux/sched_clock.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define CED_ID			0
+#define CSD_ID			4
+
+#define TIMER_ISA_MUX		0
+#define TIMER_ISA_VAL(t)	(((t) + 1) << 2)
+
+#define TIMER_INPUT_BIT(t)	(2 * (t))
+#define TIMER_ENABLE_BIT(t)	(16 + (t))
+#define TIMER_PERIODIC_BIT(t)	(12 + (t))
+
+#define TIMER_CED_INPUT_MASK	(3UL << TIMER_INPUT_BIT(CED_ID))
+#define TIMER_CSD_INPUT_MASK	(7UL << TIMER_INPUT_BIT(CSD_ID))
+
+#define TIMER_CED_UNIT_1US	0
+#define TIMER_CSD_UNIT_1US	1
+
+static void __iomem *timer_base;
+
+static u64 notrace meson6_timer_sched_read(void)
+{
+	return (u64)readl(timer_base + TIMER_ISA_VAL(CSD_ID));
+}
+
+static void meson6_clkevt_time_stop(unsigned char timer)
+{
+	u32 val = readl(timer_base + TIMER_ISA_MUX);
+
+	writel(val & ~TIMER_ENABLE_BIT(timer), timer_base + TIMER_ISA_MUX);
+}
+
+static void meson6_clkevt_time_setup(unsigned char timer, unsigned long delay)
+{
+	writel(delay, timer_base + TIMER_ISA_VAL(timer));
+}
+
+static void meson6_clkevt_time_start(unsigned char timer, bool periodic)
+{
+	u32 val = readl(timer_base + TIMER_ISA_MUX);
+
+	if (periodic)
+		val |= TIMER_PERIODIC_BIT(timer);
+	else
+		val &= ~TIMER_PERIODIC_BIT(timer);
+
+	writel(val | TIMER_ENABLE_BIT(timer), timer_base + TIMER_ISA_MUX);
+}
+
+static int meson6_shutdown(struct clock_event_device *evt)
+{
+	meson6_clkevt_time_stop(CED_ID);
+	return 0;
+}
+
+static int meson6_set_oneshot(struct clock_event_device *evt)
+{
+	meson6_clkevt_time_stop(CED_ID);
+	meson6_clkevt_time_start(CED_ID, false);
+	return 0;
+}
+
+static int meson6_set_periodic(struct clock_event_device *evt)
+{
+	meson6_clkevt_time_stop(CED_ID);
+	meson6_clkevt_time_setup(CED_ID, USEC_PER_SEC / HZ - 1);
+	meson6_clkevt_time_start(CED_ID, true);
+	return 0;
+}
+
+static int meson6_clkevt_next_event(unsigned long evt,
+				    struct clock_event_device *unused)
+{
+	meson6_clkevt_time_stop(CED_ID);
+	meson6_clkevt_time_setup(CED_ID, evt);
+	meson6_clkevt_time_start(CED_ID, false);
+
+	return 0;
+}
+
+static struct clock_event_device meson6_clockevent = {
+	.name			= "meson6_tick",
+	.rating			= 400,
+	.features		= CLOCK_EVT_FEAT_PERIODIC |
+				  CLOCK_EVT_FEAT_ONESHOT,
+	.set_state_shutdown	= meson6_shutdown,
+	.set_state_periodic	= meson6_set_periodic,
+	.set_state_oneshot	= meson6_set_oneshot,
+	.tick_resume		= meson6_shutdown,
+	.set_next_event		= meson6_clkevt_next_event,
+};
+
+static irqreturn_t meson6_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = (struct clock_event_device *)dev_id;
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static struct irqaction meson6_timer_irq = {
+	.name		= "meson6_timer",
+	.flags		= IRQF_TIMER | IRQF_IRQPOLL,
+	.handler	= meson6_timer_interrupt,
+	.dev_id		= &meson6_clockevent,
+};
+
+static int __init meson6_timer_init(struct device_node *node)
+{
+	u32 val;
+	int ret, irq;
+
+	timer_base = of_io_request_and_map(node, 0, "meson6-timer");
+	if (IS_ERR(timer_base)) {
+		pr_err("Can't map registers\n");
+		return -ENXIO;
+	}
+
+	irq = irq_of_parse_and_map(node, 0);
+	if (irq <= 0) {
+		pr_err("Can't parse IRQ\n");
+		return -EINVAL;
+	}
+
+	/* Set 1us for timer E */
+	val = readl(timer_base + TIMER_ISA_MUX);
+	val &= ~TIMER_CSD_INPUT_MASK;
+	val |= TIMER_CSD_UNIT_1US << TIMER_INPUT_BIT(CSD_ID);
+	writel(val, timer_base + TIMER_ISA_MUX);
+
+	sched_clock_register(meson6_timer_sched_read, 32, USEC_PER_SEC);
+	clocksource_mmio_init(timer_base + TIMER_ISA_VAL(CSD_ID), node->name,
+			      1000 * 1000, 300, 32, clocksource_mmio_readl_up);
+
+	/* Timer A base 1us */
+	val &= ~TIMER_CED_INPUT_MASK;
+	val |= TIMER_CED_UNIT_1US << TIMER_INPUT_BIT(CED_ID);
+	writel(val, timer_base + TIMER_ISA_MUX);
+
+	/* Stop the timer A */
+	meson6_clkevt_time_stop(CED_ID);
+
+	ret = setup_irq(irq, &meson6_timer_irq);
+	if (ret) {
+		pr_warn("failed to setup irq %d\n", irq);
+		return ret;
+	}
+
+	meson6_clockevent.cpumask = cpu_possible_mask;
+	meson6_clockevent.irq = irq;
+
+	clockevents_config_and_register(&meson6_clockevent, USEC_PER_SEC,
+					1, 0xfffe);
+	return 0;
+}
+TIMER_OF_DECLARE(meson6, "amlogic,meson6-timer",
+		       meson6_timer_init);

drivers/clocksource/mips-gic-timer.c

@@ -0,0 +1,234 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2012 MIPS Technologies, Inc.  All rights reserved.
+ */
+
+#define pr_fmt(fmt) "mips-gic-timer: " fmt
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/cpu.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/notifier.h>
+#include <linux/of_irq.h>
+#include <linux/percpu.h>
+#include <linux/smp.h>
+#include <linux/time.h>
+#include <asm/mips-cps.h>
+
+static DEFINE_PER_CPU(struct clock_event_device, gic_clockevent_device);
+static int gic_timer_irq;
+static unsigned int gic_frequency;
+
+static u64 notrace gic_read_count(void)
+{
+	unsigned int hi, hi2, lo;
+
+	if (mips_cm_is64)
+		return read_gic_counter();
+
+	do {
+		hi = read_gic_counter_32h();
+		lo = read_gic_counter_32l();
+		hi2 = read_gic_counter_32h();
+	} while (hi2 != hi);
+
+	return (((u64) hi) << 32) + lo;
+}
+
+static int gic_next_event(unsigned long delta, struct clock_event_device *evt)
+{
+	int cpu = cpumask_first(evt->cpumask);
+	u64 cnt;
+	int res;
+
+	cnt = gic_read_count();
+	cnt += (u64)delta;
+	if (cpu == raw_smp_processor_id()) {
+		write_gic_vl_compare(cnt);
+	} else {
+		write_gic_vl_other(mips_cm_vp_id(cpu));
+		write_gic_vo_compare(cnt);
+	}
+	res = ((int)(gic_read_count() - cnt) >= 0) ? -ETIME : 0;
+	return res;
+}
+
+static irqreturn_t gic_compare_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *cd = dev_id;
+
+	write_gic_vl_compare(read_gic_vl_compare());
+	cd->event_handler(cd);
+	return IRQ_HANDLED;
+}
+
+struct irqaction gic_compare_irqaction = {
+	.handler = gic_compare_interrupt,
+	.percpu_dev_id = &gic_clockevent_device,
+	.flags = IRQF_PERCPU | IRQF_TIMER,
+	.name = "timer",
+};
+
+static void gic_clockevent_cpu_init(unsigned int cpu,
+				    struct clock_event_device *cd)
+{
+	cd->name		= "MIPS GIC";
+	cd->features		= CLOCK_EVT_FEAT_ONESHOT |
+				  CLOCK_EVT_FEAT_C3STOP;
+
+	cd->rating		= 350;
+	cd->irq			= gic_timer_irq;
+	cd->cpumask		= cpumask_of(cpu);
+	cd->set_next_event	= gic_next_event;
+
+	clockevents_config_and_register(cd, gic_frequency, 0x300, 0x7fffffff);
+
+	enable_percpu_irq(gic_timer_irq, IRQ_TYPE_NONE);
+}
+
+static void gic_clockevent_cpu_exit(struct clock_event_device *cd)
+{
+	disable_percpu_irq(gic_timer_irq);
+}
+
+static void gic_update_frequency(void *data)
+{
+	unsigned long rate = (unsigned long)data;
+
+	clockevents_update_freq(this_cpu_ptr(&gic_clockevent_device), rate);
+}
+
+static int gic_starting_cpu(unsigned int cpu)
+{
+	gic_clockevent_cpu_init(cpu, this_cpu_ptr(&gic_clockevent_device));
+	return 0;
+}
+
+static int gic_clk_notifier(struct notifier_block *nb, unsigned long action,
+			    void *data)
+{
+	struct clk_notifier_data *cnd = data;
+
+	if (action == POST_RATE_CHANGE)
+		on_each_cpu(gic_update_frequency, (void *)cnd->new_rate, 1);
+
+	return NOTIFY_OK;
+}
+
+static int gic_dying_cpu(unsigned int cpu)
+{
+	gic_clockevent_cpu_exit(this_cpu_ptr(&gic_clockevent_device));
+	return 0;
+}
+
+static struct notifier_block gic_clk_nb = {
+	.notifier_call = gic_clk_notifier,
+};
+
+static int gic_clockevent_init(void)
+{
+	int ret;
+
+	if (!gic_frequency)
+		return -ENXIO;
+
+	ret = setup_percpu_irq(gic_timer_irq, &gic_compare_irqaction);
+	if (ret < 0) {
+		pr_err("IRQ %d setup failed (%d)\n", gic_timer_irq, ret);
+		return ret;
+	}
+
+	cpuhp_setup_state(CPUHP_AP_MIPS_GIC_TIMER_STARTING,
+			  "clockevents/mips/gic/timer:starting",
+			  gic_starting_cpu, gic_dying_cpu);
+	return 0;
+}
+
+static u64 gic_hpt_read(struct clocksource *cs)
+{
+	return gic_read_count();
+}
+
+static struct clocksource gic_clocksource = {
+	.name		= "GIC",
+	.read		= gic_hpt_read,
+	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
+	.archdata	= { .vdso_clock_mode = VDSO_CLOCK_GIC },
+};
+
+static int __init __gic_clocksource_init(void)
+{
+	unsigned int count_width;
+	int ret;
+
+	/* Set clocksource mask. */
+	count_width = read_gic_config() & GIC_CONFIG_COUNTBITS;
+	count_width >>= __ffs(GIC_CONFIG_COUNTBITS);
+	count_width *= 4;
+	count_width += 32;
+	gic_clocksource.mask = CLOCKSOURCE_MASK(count_width);
+
+	/* Calculate a somewhat reasonable rating value. */
+	gic_clocksource.rating = 200 + gic_frequency / 10000000;
+
+	ret = clocksource_register_hz(&gic_clocksource, gic_frequency);
+	if (ret < 0)
+		pr_warn("Unable to register clocksource\n");
+
+	return ret;
+}
+
+static int __init gic_clocksource_of_init(struct device_node *node)
+{
+	struct clk *clk;
+	int ret;
+
+	if (!mips_gic_present() || !node->parent ||
+	    !of_device_is_compatible(node->parent, "mti,gic")) {
+		pr_warn("No DT definition\n");
+		return -ENXIO;
+	}
+
+	clk = of_clk_get(node, 0);
+	if (!IS_ERR(clk)) {
+		ret = clk_prepare_enable(clk);
+		if (ret < 0) {
+			pr_err("Failed to enable clock\n");
+			clk_put(clk);
+			return ret;
+		}
+
+		gic_frequency = clk_get_rate(clk);
+	} else if (of_property_read_u32(node, "clock-frequency",
+					&gic_frequency)) {
+		pr_err("Frequency not specified\n");
+		return -EINVAL;
+	}
+	gic_timer_irq = irq_of_parse_and_map(node, 0);
+	if (!gic_timer_irq) {
+		pr_err("IRQ not specified\n");
+		return -EINVAL;
+	}
+
+	ret = __gic_clocksource_init();
+	if (ret)
+		return ret;
+
+	ret = gic_clockevent_init();
+	if (!ret && !IS_ERR(clk)) {
+		if (clk_notifier_register(clk, &gic_clk_nb) < 0)
+			pr_warn("Unable to register clock notifier\n");
+	}
+
+	/* And finally start the counter */
+	clear_gic_config(GIC_CONFIG_COUNTSTOP);
+
+	return 0;
+}
+TIMER_OF_DECLARE(mips_gic_timer, "mti,gic-timer",
+		       gic_clocksource_of_init);

drivers/clocksource/mmio.c

@@ -0,0 +1,73 @@
+/*
+ * Generic MMIO clocksource support
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/clocksource.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+
+struct clocksource_mmio {
+	void __iomem *reg;
+	struct clocksource clksrc;
+};
+
+static inline struct clocksource_mmio *to_mmio_clksrc(struct clocksource *c)
+{
+	return container_of(c, struct clocksource_mmio, clksrc);
+}
+
+u64 clocksource_mmio_readl_up(struct clocksource *c)
+{
+	return (u64)readl_relaxed(to_mmio_clksrc(c)->reg);
+}
+
+u64 clocksource_mmio_readl_down(struct clocksource *c)
+{
+	return ~(u64)readl_relaxed(to_mmio_clksrc(c)->reg) & c->mask;
+}
+
+u64 clocksource_mmio_readw_up(struct clocksource *c)
+{
+	return (u64)readw_relaxed(to_mmio_clksrc(c)->reg);
+}
+
+u64 clocksource_mmio_readw_down(struct clocksource *c)
+{
+	return ~(u64)readw_relaxed(to_mmio_clksrc(c)->reg) & c->mask;
+}
+
+/**
+ * clocksource_mmio_init - Initialize a simple mmio based clocksource
+ * @base:	Virtual address of the clock readout register
+ * @name:	Name of the clocksource
+ * @hz:		Frequency of the clocksource in Hz
+ * @rating:	Rating of the clocksource
+ * @bits:	Number of valid bits
+ * @read:	One of clocksource_mmio_read*() above
+ */
+int __init clocksource_mmio_init(void __iomem *base, const char *name,
+	unsigned long hz, int rating, unsigned bits,
+	u64 (*read)(struct clocksource *))
+{
+	struct clocksource_mmio *cs;
+
+	if (bits > 64 || bits < 16)
+		return -EINVAL;
+
+	cs = kzalloc(sizeof(struct clocksource_mmio), GFP_KERNEL);
+	if (!cs)
+		return -ENOMEM;
+
+	cs->reg = base;
+	cs->clksrc.name = name;
+	cs->clksrc.rating = rating;
+	cs->clksrc.read = read;
+	cs->clksrc.mask = CLOCKSOURCE_MASK(bits);
+	cs->clksrc.flags = CLOCK_SOURCE_IS_CONTINUOUS;
+
+	return clocksource_register_hz(&cs->clksrc, hz);
+}

drivers/clocksource/mps2-timer.c

@@ -0,0 +1,277 @@
+/*
+ * Copyright (C) 2015 ARM Limited
+ *
+ * Author: Vladimir Murzin <vladimir.murzin@arm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/of_address.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+#include <linux/slab.h>
+
+#define TIMER_CTRL		0x0
+#define TIMER_CTRL_ENABLE	BIT(0)
+#define TIMER_CTRL_IE		BIT(3)
+
+#define TIMER_VALUE		0x4
+#define TIMER_RELOAD		0x8
+#define TIMER_INT		0xc
+
+struct clockevent_mps2 {
+	void __iomem *reg;
+	u32 clock_count_per_tick;
+	struct clock_event_device clkevt;
+};
+
+static void __iomem *sched_clock_base;
+
+static u64 notrace mps2_sched_read(void)
+{
+	return ~readl_relaxed(sched_clock_base + TIMER_VALUE);
+}
+
+static inline struct clockevent_mps2 *to_mps2_clkevt(struct clock_event_device *c)
+{
+	return container_of(c, struct clockevent_mps2, clkevt);
+}
+
+static void clockevent_mps2_writel(u32 val, struct clock_event_device *c, u32 offset)
+{
+	writel_relaxed(val, to_mps2_clkevt(c)->reg + offset);
+}
+
+static int mps2_timer_shutdown(struct clock_event_device *ce)
+{
+	clockevent_mps2_writel(0, ce, TIMER_RELOAD);
+	clockevent_mps2_writel(0, ce, TIMER_CTRL);
+
+	return 0;
+}
+
+static int mps2_timer_set_next_event(unsigned long next, struct clock_event_device *ce)
+{
+	clockevent_mps2_writel(next, ce, TIMER_VALUE);
+	clockevent_mps2_writel(TIMER_CTRL_IE | TIMER_CTRL_ENABLE, ce, TIMER_CTRL);
+
+	return 0;
+}
+
+static int mps2_timer_set_periodic(struct clock_event_device *ce)
+{
+	u32 clock_count_per_tick = to_mps2_clkevt(ce)->clock_count_per_tick;
+
+	clockevent_mps2_writel(clock_count_per_tick, ce, TIMER_RELOAD);
+	clockevent_mps2_writel(clock_count_per_tick, ce, TIMER_VALUE);
+	clockevent_mps2_writel(TIMER_CTRL_IE | TIMER_CTRL_ENABLE, ce, TIMER_CTRL);
+
+	return 0;
+}
+
+static irqreturn_t mps2_timer_interrupt(int irq, void *dev_id)
+{
+	struct clockevent_mps2 *ce = dev_id;
+	u32 status = readl_relaxed(ce->reg + TIMER_INT);
+
+	if (!status) {
+		pr_warn("spurious interrupt\n");
+		return IRQ_NONE;
+	}
+
+	writel_relaxed(1, ce->reg + TIMER_INT);
+
+	ce->clkevt.event_handler(&ce->clkevt);
+
+	return IRQ_HANDLED;
+}
+
+static int __init mps2_clockevent_init(struct device_node *np)
+{
+	void __iomem *base;
+	struct clk *clk = NULL;
+	struct clockevent_mps2 *ce;
+	u32 rate;
+	int irq, ret;
+	const char *name = "mps2-clkevt";
+
+	ret = of_property_read_u32(np, "clock-frequency", &rate);
+	if (ret) {
+		clk = of_clk_get(np, 0);
+		if (IS_ERR(clk)) {
+			ret = PTR_ERR(clk);
+			pr_err("failed to get clock for clockevent: %d\n", ret);
+			goto out;
+		}
+
+		ret = clk_prepare_enable(clk);
+		if (ret) {
+			pr_err("failed to enable clock for clockevent: %d\n", ret);
+			goto out_clk_put;
+		}
+
+		rate = clk_get_rate(clk);
+	}
+
+	base = of_iomap(np, 0);
+	if (!base) {
+		ret = -EADDRNOTAVAIL;
+		pr_err("failed to map register for clockevent: %d\n", ret);
+		goto out_clk_disable;
+	}
+
+	irq = irq_of_parse_and_map(np, 0);
+	if (!irq) {
+		ret = -ENOENT;
+		pr_err("failed to get irq for clockevent: %d\n", ret);
+		goto out_iounmap;
+	}
+
+	ce = kzalloc(sizeof(*ce), GFP_KERNEL);
+	if (!ce) {
+		ret = -ENOMEM;
+		goto out_iounmap;
+	}
+
+	ce->reg = base;
+	ce->clock_count_per_tick = DIV_ROUND_CLOSEST(rate, HZ);
+	ce->clkevt.irq = irq;
+	ce->clkevt.name = name;
+	ce->clkevt.rating = 200;
+	ce->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
+	ce->clkevt.cpumask = cpu_possible_mask;
+	ce->clkevt.set_state_shutdown	= mps2_timer_shutdown,
+	ce->clkevt.set_state_periodic	= mps2_timer_set_periodic,
+	ce->clkevt.set_state_oneshot	= mps2_timer_shutdown,
+	ce->clkevt.set_next_event	= mps2_timer_set_next_event;
+
+	/* Ensure timer is disabled */
+	writel_relaxed(0, base + TIMER_CTRL);
+
+	ret = request_irq(irq, mps2_timer_interrupt, IRQF_TIMER, name, ce);
+	if (ret) {
+		pr_err("failed to request irq for clockevent: %d\n", ret);
+		goto out_kfree;
+	}
+
+	clockevents_config_and_register(&ce->clkevt, rate, 0xf, 0xffffffff);
+
+	return 0;
+
+out_kfree:
+	kfree(ce);
+out_iounmap:
+	iounmap(base);
+out_clk_disable:
+	/* clk_{disable, unprepare, put}() can handle NULL as a parameter */
+	clk_disable_unprepare(clk);
+out_clk_put:
+	clk_put(clk);
+out:
+	return ret;
+}
+
+static int __init mps2_clocksource_init(struct device_node *np)
+{
+	void __iomem *base;
+	struct clk *clk = NULL;
+	u32 rate;
+	int ret;
+	const char *name = "mps2-clksrc";
+
+	ret = of_property_read_u32(np, "clock-frequency", &rate);
+	if (ret) {
+		clk = of_clk_get(np, 0);
+		if (IS_ERR(clk)) {
+			ret = PTR_ERR(clk);
+			pr_err("failed to get clock for clocksource: %d\n", ret);
+			goto out;
+		}
+
+		ret = clk_prepare_enable(clk);
+		if (ret) {
+			pr_err("failed to enable clock for clocksource: %d\n", ret);
+			goto out_clk_put;
+		}
+
+		rate = clk_get_rate(clk);
+	}
+
+	base = of_iomap(np, 0);
+	if (!base) {
+		ret = -EADDRNOTAVAIL;
+		pr_err("failed to map register for clocksource: %d\n", ret);
+		goto out_clk_disable;
+	}
+
+	/* Ensure timer is disabled */
+	writel_relaxed(0, base + TIMER_CTRL);
+
+	/* ... and set it up as free-running clocksource */
+	writel_relaxed(0xffffffff, base + TIMER_VALUE);
+	writel_relaxed(0xffffffff, base + TIMER_RELOAD);
+
+	writel_relaxed(TIMER_CTRL_ENABLE, base + TIMER_CTRL);
+
+	ret = clocksource_mmio_init(base + TIMER_VALUE, name,
+				    rate, 200, 32,
+				    clocksource_mmio_readl_down);
+	if (ret) {
+		pr_err("failed to init clocksource: %d\n", ret);
+		goto out_iounmap;
+	}
+
+	sched_clock_base = base;
+	sched_clock_register(mps2_sched_read, 32, rate);
+
+	return 0;
+
+out_iounmap:
+	iounmap(base);
+out_clk_disable:
+	/* clk_{disable, unprepare, put}() can handle NULL as a parameter */
+	clk_disable_unprepare(clk);
+out_clk_put:
+	clk_put(clk);
+out:
+	return ret;
+}
+
+static int __init mps2_timer_init(struct device_node *np)
+{
+	static int has_clocksource, has_clockevent;
+	int ret;
+
+	if (!has_clocksource) {
+		ret = mps2_clocksource_init(np);
+		if (!ret) {
+			has_clocksource = 1;
+			return 0;
+		}
+	}
+
+	if (!has_clockevent) {
+		ret = mps2_clockevent_init(np);
+		if (!ret) {
+			has_clockevent = 1;
+			return 0;
+		}
+	}
+
+	return 0;
+}
+
+TIMER_OF_DECLARE(mps2_timer, "arm,mps2-timer", mps2_timer_init);

drivers/clocksource/mxs_timer.c

@@ -0,0 +1,279 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+//  Copyright (C) 2000-2001 Deep Blue Solutions
+//  Copyright (C) 2002 Shane Nay (shane@minirl.com)
+//  Copyright (C) 2006-2007 Pavel Pisa (ppisa@pikron.com)
+//  Copyright (C) 2008 Juergen Beisert (kernel@pengutronix.de)
+//  Copyright (C) 2010 Freescale Semiconductor, Inc. All Rights Reserved.
+
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/clockchips.h>
+#include <linux/clk.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/stmp_device.h>
+#include <linux/sched_clock.h>
+
+/*
+ * There are 2 versions of the timrot on Freescale MXS-based SoCs.
+ * The v1 on MX23 only gets 16 bits counter, while v2 on MX28
+ * extends the counter to 32 bits.
+ *
+ * The implementation uses two timers, one for clock_event and
+ * another for clocksource. MX28 uses timrot 0 and 1, while MX23
+ * uses 0 and 2.
+ */
+
+#define MX23_TIMROT_VERSION_OFFSET	0x0a0
+#define MX28_TIMROT_VERSION_OFFSET	0x120
+#define BP_TIMROT_MAJOR_VERSION		24
+#define BV_TIMROT_VERSION_1		0x01
+#define BV_TIMROT_VERSION_2		0x02
+#define timrot_is_v1()	(timrot_major_version == BV_TIMROT_VERSION_1)
+
+/*
+ * There are 4 registers for each timrotv2 instance, and 2 registers
+ * for each timrotv1. So address step 0x40 in macros below strides
+ * one instance of timrotv2 while two instances of timrotv1.
+ *
+ * As the result, HW_TIMROT_XXXn(1) defines the address of timrot1
+ * on MX28 while timrot2 on MX23.
+ */
+/* common between v1 and v2 */
+#define HW_TIMROT_ROTCTRL		0x00
+#define HW_TIMROT_TIMCTRLn(n)		(0x20 + (n) * 0x40)
+/* v1 only */
+#define HW_TIMROT_TIMCOUNTn(n)		(0x30 + (n) * 0x40)
+/* v2 only */
+#define HW_TIMROT_RUNNING_COUNTn(n)	(0x30 + (n) * 0x40)
+#define HW_TIMROT_FIXED_COUNTn(n)	(0x40 + (n) * 0x40)
+
+#define BM_TIMROT_TIMCTRLn_RELOAD	(1 << 6)
+#define BM_TIMROT_TIMCTRLn_UPDATE	(1 << 7)
+#define BM_TIMROT_TIMCTRLn_IRQ_EN	(1 << 14)
+#define BM_TIMROT_TIMCTRLn_IRQ		(1 << 15)
+#define BP_TIMROT_TIMCTRLn_SELECT	0
+#define BV_TIMROTv1_TIMCTRLn_SELECT__32KHZ_XTAL		0x8
+#define BV_TIMROTv2_TIMCTRLn_SELECT__32KHZ_XTAL		0xb
+#define BV_TIMROTv2_TIMCTRLn_SELECT__TICK_ALWAYS	0xf
+
+static struct clock_event_device mxs_clockevent_device;
+
+static void __iomem *mxs_timrot_base;
+static u32 timrot_major_version;
+
+static inline void timrot_irq_disable(void)
+{
+	__raw_writel(BM_TIMROT_TIMCTRLn_IRQ_EN, mxs_timrot_base +
+		     HW_TIMROT_TIMCTRLn(0) + STMP_OFFSET_REG_CLR);
+}
+
+static inline void timrot_irq_enable(void)
+{
+	__raw_writel(BM_TIMROT_TIMCTRLn_IRQ_EN, mxs_timrot_base +
+		     HW_TIMROT_TIMCTRLn(0) + STMP_OFFSET_REG_SET);
+}
+
+static void timrot_irq_acknowledge(void)
+{
+	__raw_writel(BM_TIMROT_TIMCTRLn_IRQ, mxs_timrot_base +
+		     HW_TIMROT_TIMCTRLn(0) + STMP_OFFSET_REG_CLR);
+}
+
+static u64 timrotv1_get_cycles(struct clocksource *cs)
+{
+	return ~((__raw_readl(mxs_timrot_base + HW_TIMROT_TIMCOUNTn(1))
+			& 0xffff0000) >> 16);
+}
+
+static int timrotv1_set_next_event(unsigned long evt,
+					struct clock_event_device *dev)
+{
+	/* timrot decrements the count */
+	__raw_writel(evt, mxs_timrot_base + HW_TIMROT_TIMCOUNTn(0));
+
+	return 0;
+}
+
+static int timrotv2_set_next_event(unsigned long evt,
+					struct clock_event_device *dev)
+{
+	/* timrot decrements the count */
+	__raw_writel(evt, mxs_timrot_base + HW_TIMROT_FIXED_COUNTn(0));
+
+	return 0;
+}
+
+static irqreturn_t mxs_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	timrot_irq_acknowledge();
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static struct irqaction mxs_timer_irq = {
+	.name		= "MXS Timer Tick",
+	.dev_id		= &mxs_clockevent_device,
+	.flags		= IRQF_TIMER | IRQF_IRQPOLL,
+	.handler	= mxs_timer_interrupt,
+};
+
+static void mxs_irq_clear(char *state)
+{
+	/* Disable interrupt in timer module */
+	timrot_irq_disable();
+
+	/* Set event time into the furthest future */
+	if (timrot_is_v1())
+		__raw_writel(0xffff, mxs_timrot_base + HW_TIMROT_TIMCOUNTn(1));
+	else
+		__raw_writel(0xffffffff,
+			     mxs_timrot_base + HW_TIMROT_FIXED_COUNTn(1));
+
+	/* Clear pending interrupt */
+	timrot_irq_acknowledge();
+	pr_debug("%s: changing mode to %s\n", __func__, state);
+}
+
+static int mxs_shutdown(struct clock_event_device *evt)
+{
+	mxs_irq_clear("shutdown");
+
+	return 0;
+}
+
+static int mxs_set_oneshot(struct clock_event_device *evt)
+{
+	if (clockevent_state_oneshot(evt))
+		mxs_irq_clear("oneshot");
+	timrot_irq_enable();
+	return 0;
+}
+
+static struct clock_event_device mxs_clockevent_device = {
+	.name			= "mxs_timrot",
+	.features		= CLOCK_EVT_FEAT_ONESHOT,
+	.set_state_shutdown	= mxs_shutdown,
+	.set_state_oneshot	= mxs_set_oneshot,
+	.tick_resume		= mxs_shutdown,
+	.set_next_event		= timrotv2_set_next_event,
+	.rating			= 200,
+};
+
+static int __init mxs_clockevent_init(struct clk *timer_clk)
+{
+	if (timrot_is_v1())
+		mxs_clockevent_device.set_next_event = timrotv1_set_next_event;
+	mxs_clockevent_device.cpumask = cpumask_of(0);
+	clockevents_config_and_register(&mxs_clockevent_device,
+					clk_get_rate(timer_clk),
+					timrot_is_v1() ? 0xf : 0x2,
+					timrot_is_v1() ? 0xfffe : 0xfffffffe);
+
+	return 0;
+}
+
+static struct clocksource clocksource_mxs = {
+	.name		= "mxs_timer",
+	.rating		= 200,
+	.read		= timrotv1_get_cycles,
+	.mask		= CLOCKSOURCE_MASK(16),
+	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static u64 notrace mxs_read_sched_clock_v2(void)
+{
+	return ~readl_relaxed(mxs_timrot_base + HW_TIMROT_RUNNING_COUNTn(1));
+}
+
+static int __init mxs_clocksource_init(struct clk *timer_clk)
+{
+	unsigned int c = clk_get_rate(timer_clk);
+
+	if (timrot_is_v1())
+		clocksource_register_hz(&clocksource_mxs, c);
+	else {
+		clocksource_mmio_init(mxs_timrot_base + HW_TIMROT_RUNNING_COUNTn(1),
+			"mxs_timer", c, 200, 32, clocksource_mmio_readl_down);
+		sched_clock_register(mxs_read_sched_clock_v2, 32, c);
+	}
+
+	return 0;
+}
+
+static int __init mxs_timer_init(struct device_node *np)
+{
+	struct clk *timer_clk;
+	int irq, ret;
+
+	mxs_timrot_base = of_iomap(np, 0);
+	WARN_ON(!mxs_timrot_base);
+
+	timer_clk = of_clk_get(np, 0);
+	if (IS_ERR(timer_clk)) {
+		pr_err("%s: failed to get clk\n", __func__);
+		return PTR_ERR(timer_clk);
+	}
+
+	ret = clk_prepare_enable(timer_clk);
+	if (ret)
+		return ret;
+
+	/*
+	 * Initialize timers to a known state
+	 */
+	stmp_reset_block(mxs_timrot_base + HW_TIMROT_ROTCTRL);
+
+	/* get timrot version */
+	timrot_major_version = __raw_readl(mxs_timrot_base +
+			(of_device_is_compatible(np, "fsl,imx23-timrot") ?
+						MX23_TIMROT_VERSION_OFFSET :
+						MX28_TIMROT_VERSION_OFFSET));
+	timrot_major_version >>= BP_TIMROT_MAJOR_VERSION;
+
+	/* one for clock_event */
+	__raw_writel((timrot_is_v1() ?
+			BV_TIMROTv1_TIMCTRLn_SELECT__32KHZ_XTAL :
+			BV_TIMROTv2_TIMCTRLn_SELECT__TICK_ALWAYS) |
+			BM_TIMROT_TIMCTRLn_UPDATE |
+			BM_TIMROT_TIMCTRLn_IRQ_EN,
+			mxs_timrot_base + HW_TIMROT_TIMCTRLn(0));
+
+	/* another for clocksource */
+	__raw_writel((timrot_is_v1() ?
+			BV_TIMROTv1_TIMCTRLn_SELECT__32KHZ_XTAL :
+			BV_TIMROTv2_TIMCTRLn_SELECT__TICK_ALWAYS) |
+			BM_TIMROT_TIMCTRLn_RELOAD,
+			mxs_timrot_base + HW_TIMROT_TIMCTRLn(1));
+
+	/* set clocksource timer fixed count to the maximum */
+	if (timrot_is_v1())
+		__raw_writel(0xffff,
+			mxs_timrot_base + HW_TIMROT_TIMCOUNTn(1));
+	else
+		__raw_writel(0xffffffff,
+			mxs_timrot_base + HW_TIMROT_FIXED_COUNTn(1));
+
+	/* init and register the timer to the framework */
+	ret = mxs_clocksource_init(timer_clk);
+	if (ret)
+		return ret;
+
+	ret = mxs_clockevent_init(timer_clk);
+	if (ret)
+		return ret;
+
+	/* Make irqs happen */
+	irq = irq_of_parse_and_map(np, 0);
+	if (irq <= 0)
+		return -EINVAL;
+
+	return setup_irq(irq, &mxs_timer_irq);
+}
+TIMER_OF_DECLARE(mxs, "fsl,timrot", mxs_timer_init);

drivers/clocksource/nomadik-mtu.c

@@ -0,0 +1,288 @@
+/*
+ * Copyright (C) 2008 STMicroelectronics
+ * Copyright (C) 2010 Alessandro Rubini
+ * Copyright (C) 2010 Linus Walleij for ST-Ericsson
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ */
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include <linux/clk.h>
+#include <linux/jiffies.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/sched_clock.h>
+#include <asm/mach/time.h>
+
+/*
+ * The MTU device hosts four different counters, with 4 set of
+ * registers. These are register names.
+ */
+
+#define MTU_IMSC	0x00	/* Interrupt mask set/clear */
+#define MTU_RIS		0x04	/* Raw interrupt status */
+#define MTU_MIS		0x08	/* Masked interrupt status */
+#define MTU_ICR		0x0C	/* Interrupt clear register */
+
+/* per-timer registers take 0..3 as argument */
+#define MTU_LR(x)	(0x10 + 0x10 * (x) + 0x00)	/* Load value */
+#define MTU_VAL(x)	(0x10 + 0x10 * (x) + 0x04)	/* Current value */
+#define MTU_CR(x)	(0x10 + 0x10 * (x) + 0x08)	/* Control reg */
+#define MTU_BGLR(x)	(0x10 + 0x10 * (x) + 0x0c)	/* At next overflow */
+
+/* bits for the control register */
+#define MTU_CRn_ENA		0x80
+#define MTU_CRn_PERIODIC	0x40	/* if 0 = free-running */
+#define MTU_CRn_PRESCALE_MASK	0x0c
+#define MTU_CRn_PRESCALE_1		0x00
+#define MTU_CRn_PRESCALE_16		0x04
+#define MTU_CRn_PRESCALE_256		0x08
+#define MTU_CRn_32BITS		0x02
+#define MTU_CRn_ONESHOT		0x01	/* if 0 = wraps reloading from BGLR*/
+
+/* Other registers are usual amba/primecell registers, currently not used */
+#define MTU_ITCR	0xff0
+#define MTU_ITOP	0xff4
+
+#define MTU_PERIPH_ID0	0xfe0
+#define MTU_PERIPH_ID1	0xfe4
+#define MTU_PERIPH_ID2	0xfe8
+#define MTU_PERIPH_ID3	0xfeC
+
+#define MTU_PCELL0	0xff0
+#define MTU_PCELL1	0xff4
+#define MTU_PCELL2	0xff8
+#define MTU_PCELL3	0xffC
+
+static void __iomem *mtu_base;
+static bool clkevt_periodic;
+static u32 clk_prescale;
+static u32 nmdk_cycle;		/* write-once */
+static struct delay_timer mtu_delay_timer;
+
+#ifdef CONFIG_CLKSRC_NOMADIK_MTU_SCHED_CLOCK
+/*
+ * Override the global weak sched_clock symbol with this
+ * local implementation which uses the clocksource to get some
+ * better resolution when scheduling the kernel.
+ */
+static u64 notrace nomadik_read_sched_clock(void)
+{
+	if (unlikely(!mtu_base))
+		return 0;
+
+	return -readl(mtu_base + MTU_VAL(0));
+}
+#endif
+
+static unsigned long nmdk_timer_read_current_timer(void)
+{
+	return ~readl_relaxed(mtu_base + MTU_VAL(0));
+}
+
+/* Clockevent device: use one-shot mode */
+static int nmdk_clkevt_next(unsigned long evt, struct clock_event_device *ev)
+{
+	writel(1 << 1, mtu_base + MTU_IMSC);
+	writel(evt, mtu_base + MTU_LR(1));
+	/* Load highest value, enable device, enable interrupts */
+	writel(MTU_CRn_ONESHOT | clk_prescale |
+	       MTU_CRn_32BITS | MTU_CRn_ENA,
+	       mtu_base + MTU_CR(1));
+
+	return 0;
+}
+
+static void nmdk_clkevt_reset(void)
+{
+	if (clkevt_periodic) {
+		/* Timer: configure load and background-load, and fire it up */
+		writel(nmdk_cycle, mtu_base + MTU_LR(1));
+		writel(nmdk_cycle, mtu_base + MTU_BGLR(1));
+
+		writel(MTU_CRn_PERIODIC | clk_prescale |
+		       MTU_CRn_32BITS | MTU_CRn_ENA,
+		       mtu_base + MTU_CR(1));
+		writel(1 << 1, mtu_base + MTU_IMSC);
+	} else {
+		/* Generate an interrupt to start the clockevent again */
+		(void) nmdk_clkevt_next(nmdk_cycle, NULL);
+	}
+}
+
+static int nmdk_clkevt_shutdown(struct clock_event_device *evt)
+{
+	writel(0, mtu_base + MTU_IMSC);
+	/* disable timer */
+	writel(0, mtu_base + MTU_CR(1));
+	/* load some high default value */
+	writel(0xffffffff, mtu_base + MTU_LR(1));
+	return 0;
+}
+
+static int nmdk_clkevt_set_oneshot(struct clock_event_device *evt)
+{
+	clkevt_periodic = false;
+	return 0;
+}
+
+static int nmdk_clkevt_set_periodic(struct clock_event_device *evt)
+{
+	clkevt_periodic = true;
+	nmdk_clkevt_reset();
+	return 0;
+}
+
+static void nmdk_clksrc_reset(void)
+{
+	/* Disable */
+	writel(0, mtu_base + MTU_CR(0));
+
+	/* ClockSource: configure load and background-load, and fire it up */
+	writel(nmdk_cycle, mtu_base + MTU_LR(0));
+	writel(nmdk_cycle, mtu_base + MTU_BGLR(0));
+
+	writel(clk_prescale | MTU_CRn_32BITS | MTU_CRn_ENA,
+	       mtu_base + MTU_CR(0));
+}
+
+static void nmdk_clkevt_resume(struct clock_event_device *cedev)
+{
+	nmdk_clkevt_reset();
+	nmdk_clksrc_reset();
+}
+
+static struct clock_event_device nmdk_clkevt = {
+	.name			= "mtu_1",
+	.features		= CLOCK_EVT_FEAT_ONESHOT |
+				  CLOCK_EVT_FEAT_PERIODIC |
+				  CLOCK_EVT_FEAT_DYNIRQ,
+	.rating			= 200,
+	.set_state_shutdown	= nmdk_clkevt_shutdown,
+	.set_state_periodic	= nmdk_clkevt_set_periodic,
+	.set_state_oneshot	= nmdk_clkevt_set_oneshot,
+	.set_next_event		= nmdk_clkevt_next,
+	.resume			= nmdk_clkevt_resume,
+};
+
+/*
+ * IRQ Handler for timer 1 of the MTU block.
+ */
+static irqreturn_t nmdk_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evdev = dev_id;
+
+	writel(1 << 1, mtu_base + MTU_ICR); /* Interrupt clear reg */
+	evdev->event_handler(evdev);
+	return IRQ_HANDLED;
+}
+
+static struct irqaction nmdk_timer_irq = {
+	.name		= "Nomadik Timer Tick",
+	.flags		= IRQF_TIMER,
+	.handler	= nmdk_timer_interrupt,
+	.dev_id		= &nmdk_clkevt,
+};
+
+static int __init nmdk_timer_init(void __iomem *base, int irq,
+				   struct clk *pclk, struct clk *clk)
+{
+	unsigned long rate;
+	int ret;
+
+	mtu_base = base;
+
+	BUG_ON(clk_prepare_enable(pclk));
+	BUG_ON(clk_prepare_enable(clk));
+
+	/*
+	 * Tick rate is 2.4MHz for Nomadik and 2.4Mhz, 100MHz or 133 MHz
+	 * for ux500.
+	 * Use a divide-by-16 counter if the tick rate is more than 32MHz.
+	 * At 32 MHz, the timer (with 32 bit counter) can be programmed
+	 * to wake-up at a max 127s a head in time. Dividing a 2.4 MHz timer
+	 * with 16 gives too low timer resolution.
+	 */
+	rate = clk_get_rate(clk);
+	if (rate > 32000000) {
+		rate /= 16;
+		clk_prescale = MTU_CRn_PRESCALE_16;
+	} else {
+		clk_prescale = MTU_CRn_PRESCALE_1;
+	}
+
+	/* Cycles for periodic mode */
+	nmdk_cycle = DIV_ROUND_CLOSEST(rate, HZ);
+
+
+	/* Timer 0 is the free running clocksource */
+	nmdk_clksrc_reset();
+
+	ret = clocksource_mmio_init(mtu_base + MTU_VAL(0), "mtu_0",
+				    rate, 200, 32, clocksource_mmio_readl_down);
+	if (ret) {
+		pr_err("timer: failed to initialize clock source %s\n", "mtu_0");
+		return ret;
+	}
+
+#ifdef CONFIG_CLKSRC_NOMADIK_MTU_SCHED_CLOCK
+	sched_clock_register(nomadik_read_sched_clock, 32, rate);
+#endif
+
+	/* Timer 1 is used for events, register irq and clockevents */
+	setup_irq(irq, &nmdk_timer_irq);
+	nmdk_clkevt.cpumask = cpumask_of(0);
+	nmdk_clkevt.irq = irq;
+	clockevents_config_and_register(&nmdk_clkevt, rate, 2, 0xffffffffU);
+
+	mtu_delay_timer.read_current_timer = &nmdk_timer_read_current_timer;
+	mtu_delay_timer.freq = rate;
+	register_current_timer_delay(&mtu_delay_timer);
+
+	return 0;
+}
+
+static int __init nmdk_timer_of_init(struct device_node *node)
+{
+	struct clk *pclk;
+	struct clk *clk;
+	void __iomem *base;
+	int irq;
+
+	base = of_iomap(node, 0);
+	if (!base) {
+		pr_err("Can't remap registers\n");
+		return -ENXIO;
+	}
+
+	pclk = of_clk_get_by_name(node, "apb_pclk");
+	if (IS_ERR(pclk)) {
+		pr_err("could not get apb_pclk\n");
+		return PTR_ERR(pclk);
+	}
+
+	clk = of_clk_get_by_name(node, "timclk");
+	if (IS_ERR(clk)) {
+		pr_err("could not get timclk\n");
+		return PTR_ERR(clk);
+	}
+
+	irq = irq_of_parse_and_map(node, 0);
+	if (irq <= 0) {
+		pr_err("Can't parse IRQ\n");
+		return -EINVAL;
+	}
+
+	return nmdk_timer_init(base, irq, pclk, clk);
+}
+TIMER_OF_DECLARE(nomadik_mtu, "st,nomadik-mtu",
+		       nmdk_timer_of_init);

drivers/clocksource/numachip.c

@@ -0,0 +1,97 @@
+/*
+ *
+ * Copyright (C) 2015 Numascale AS. All rights reserved.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/clockchips.h>
+
+#include <asm/irq.h>
+#include <asm/numachip/numachip.h>
+#include <asm/numachip/numachip_csr.h>
+
+static DEFINE_PER_CPU(struct clock_event_device, numachip2_ced);
+
+static cycles_t numachip2_timer_read(struct clocksource *cs)
+{
+	return numachip2_read64_lcsr(NUMACHIP2_TIMER_NOW);
+}
+
+static struct clocksource numachip2_clocksource = {
+	.name            = "numachip2",
+	.rating          = 295,
+	.read            = numachip2_timer_read,
+	.mask            = CLOCKSOURCE_MASK(64),
+	.flags           = CLOCK_SOURCE_IS_CONTINUOUS,
+	.mult            = 1,
+	.shift           = 0,
+};
+
+static int numachip2_set_next_event(unsigned long delta, struct clock_event_device *ced)
+{
+	numachip2_write64_lcsr(NUMACHIP2_TIMER_DEADLINE + numachip2_timer(),
+		delta);
+	return 0;
+}
+
+static const struct clock_event_device numachip2_clockevent __initconst = {
+	.name            = "numachip2",
+	.rating          = 400,
+	.set_next_event  = numachip2_set_next_event,
+	.features        = CLOCK_EVT_FEAT_ONESHOT,
+	.mult            = 1,
+	.shift           = 0,
+	.min_delta_ns    = 1250,
+	.min_delta_ticks = 1250,
+	.max_delta_ns    = LONG_MAX,
+	.max_delta_ticks = LONG_MAX,
+};
+
+static void numachip_timer_interrupt(void)
+{
+	struct clock_event_device *ced = this_cpu_ptr(&numachip2_ced);
+
+	ced->event_handler(ced);
+}
+
+static __init void numachip_timer_each(struct work_struct *work)
+{
+	unsigned local_apicid = __this_cpu_read(x86_cpu_to_apicid) & 0xff;
+	struct clock_event_device *ced = this_cpu_ptr(&numachip2_ced);
+
+	/* Setup IPI vector to local core and relative timing mode */
+	numachip2_write64_lcsr(NUMACHIP2_TIMER_INT + numachip2_timer(),
+		(3 << 22) | (X86_PLATFORM_IPI_VECTOR << 14) |
+		(local_apicid << 6));
+
+	*ced = numachip2_clockevent;
+	ced->cpumask = cpumask_of(smp_processor_id());
+	clockevents_register_device(ced);
+}
+
+static int __init numachip_timer_init(void)
+{
+	if (numachip_system != 2)
+		return -ENODEV;
+
+	/* Reset timer */
+	numachip2_write64_lcsr(NUMACHIP2_TIMER_RESET, 0);
+	clocksource_register_hz(&numachip2_clocksource, NSEC_PER_SEC);
+
+	/* Setup per-cpu clockevents */
+	x86_platform_ipi_callback = numachip_timer_interrupt;
+	schedule_on_each_cpu(&numachip_timer_each);
+
+	return 0;
+}
+
+arch_initcall(numachip_timer_init);

drivers/clocksource/owl-timer.c

@@ -0,0 +1,173 @@
+/*
+ * Actions Semi Owl timer
+ *
+ * Copyright 2012 Actions Semi Inc.
+ * Author: Actions Semi, Inc.
+ *
+ * Copyright (c) 2017 SUSE Linux GmbH
+ * Author: Andreas Färber
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqreturn.h>
+#include <linux/sched_clock.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define OWL_Tx_CTL		0x0
+#define OWL_Tx_CMP		0x4
+#define OWL_Tx_VAL		0x8
+
+#define OWL_Tx_CTL_PD		BIT(0)
+#define OWL_Tx_CTL_INTEN	BIT(1)
+#define OWL_Tx_CTL_EN		BIT(2)
+
+static void __iomem *owl_timer_base;
+static void __iomem *owl_clksrc_base;
+static void __iomem *owl_clkevt_base;
+
+static inline void owl_timer_reset(void __iomem *base)
+{
+	writel(0, base + OWL_Tx_CTL);
+	writel(0, base + OWL_Tx_VAL);
+	writel(0, base + OWL_Tx_CMP);
+}
+
+static inline void owl_timer_set_enabled(void __iomem *base, bool enabled)
+{
+	u32 ctl = readl(base + OWL_Tx_CTL);
+
+	/* PD bit is cleared when set */
+	ctl &= ~OWL_Tx_CTL_PD;
+
+	if (enabled)
+		ctl |= OWL_Tx_CTL_EN;
+	else
+		ctl &= ~OWL_Tx_CTL_EN;
+
+	writel(ctl, base + OWL_Tx_CTL);
+}
+
+static u64 notrace owl_timer_sched_read(void)
+{
+	return (u64)readl(owl_clksrc_base + OWL_Tx_VAL);
+}
+
+static int owl_timer_set_state_shutdown(struct clock_event_device *evt)
+{
+	owl_timer_set_enabled(owl_clkevt_base, false);
+
+	return 0;
+}
+
+static int owl_timer_set_state_oneshot(struct clock_event_device *evt)
+{
+	owl_timer_reset(owl_clkevt_base);
+
+	return 0;
+}
+
+static int owl_timer_tick_resume(struct clock_event_device *evt)
+{
+	return 0;
+}
+
+static int owl_timer_set_next_event(unsigned long evt,
+				    struct clock_event_device *ev)
+{
+	void __iomem *base = owl_clkevt_base;
+
+	owl_timer_set_enabled(base, false);
+	writel(OWL_Tx_CTL_INTEN, base + OWL_Tx_CTL);
+	writel(0, base + OWL_Tx_VAL);
+	writel(evt, base + OWL_Tx_CMP);
+	owl_timer_set_enabled(base, true);
+
+	return 0;
+}
+
+static struct clock_event_device owl_clockevent = {
+	.name			= "owl_tick",
+	.rating			= 200,
+	.features		= CLOCK_EVT_FEAT_ONESHOT |
+				  CLOCK_EVT_FEAT_DYNIRQ,
+	.set_state_shutdown	= owl_timer_set_state_shutdown,
+	.set_state_oneshot	= owl_timer_set_state_oneshot,
+	.tick_resume		= owl_timer_tick_resume,
+	.set_next_event		= owl_timer_set_next_event,
+};
+
+static irqreturn_t owl_timer1_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = (struct clock_event_device *)dev_id;
+
+	writel(OWL_Tx_CTL_PD, owl_clkevt_base + OWL_Tx_CTL);
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static int __init owl_timer_init(struct device_node *node)
+{
+	struct clk *clk;
+	unsigned long rate;
+	int timer1_irq, ret;
+
+	owl_timer_base = of_io_request_and_map(node, 0, "owl-timer");
+	if (IS_ERR(owl_timer_base)) {
+		pr_err("Can't map timer registers\n");
+		return PTR_ERR(owl_timer_base);
+	}
+
+	owl_clksrc_base = owl_timer_base + 0x08;
+	owl_clkevt_base = owl_timer_base + 0x14;
+
+	timer1_irq = of_irq_get_byname(node, "timer1");
+	if (timer1_irq <= 0) {
+		pr_err("Can't parse timer1 IRQ\n");
+		return -EINVAL;
+	}
+
+	clk = of_clk_get(node, 0);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	rate = clk_get_rate(clk);
+
+	owl_timer_reset(owl_clksrc_base);
+	owl_timer_set_enabled(owl_clksrc_base, true);
+
+	sched_clock_register(owl_timer_sched_read, 32, rate);
+	clocksource_mmio_init(owl_clksrc_base + OWL_Tx_VAL, node->name,
+			      rate, 200, 32, clocksource_mmio_readl_up);
+
+	owl_timer_reset(owl_clkevt_base);
+
+	ret = request_irq(timer1_irq, owl_timer1_interrupt, IRQF_TIMER,
+			  "owl-timer", &owl_clockevent);
+	if (ret) {
+		pr_err("failed to request irq %d\n", timer1_irq);
+		return ret;
+	}
+
+	owl_clockevent.cpumask = cpumask_of(0);
+	owl_clockevent.irq = timer1_irq;
+
+	clockevents_config_and_register(&owl_clockevent, rate,
+					0xf, 0xffffffff);
+
+	return 0;
+}
+TIMER_OF_DECLARE(owl_s500, "actions,s500-timer", owl_timer_init);
+TIMER_OF_DECLARE(owl_s700, "actions,s700-timer", owl_timer_init);
+TIMER_OF_DECLARE(owl_s900, "actions,s900-timer", owl_timer_init);

drivers/clocksource/pxa_timer.c

@@ -0,0 +1,236 @@
+/*
+ * arch/arm/mach-pxa/time.c
+ *
+ * PXA clocksource, clockevents, and OST interrupt handlers.
+ * Copyright (c) 2007 by Bill Gatliff <bgat@billgatliff.com>.
+ *
+ * Derived from Nicolas Pitre's PXA timer handler Copyright (c) 2001
+ * by MontaVista Software, Inc.  (Nico, your code rocks!)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched/clock.h>
+#include <linux/sched_clock.h>
+
+#include <clocksource/pxa.h>
+
+#include <asm/div64.h>
+
+#define OSMR0		0x00	/* OS Timer 0 Match Register */
+#define OSMR1		0x04	/* OS Timer 1 Match Register */
+#define OSMR2		0x08	/* OS Timer 2 Match Register */
+#define OSMR3		0x0C	/* OS Timer 3 Match Register */
+
+#define OSCR		0x10	/* OS Timer Counter Register */
+#define OSSR		0x14	/* OS Timer Status Register */
+#define OWER		0x18	/* OS Timer Watchdog Enable Register */
+#define OIER		0x1C	/* OS Timer Interrupt Enable Register */
+
+#define OSSR_M3		(1 << 3)	/* Match status channel 3 */
+#define OSSR_M2		(1 << 2)	/* Match status channel 2 */
+#define OSSR_M1		(1 << 1)	/* Match status channel 1 */
+#define OSSR_M0		(1 << 0)	/* Match status channel 0 */
+
+#define OIER_E0		(1 << 0)	/* Interrupt enable channel 0 */
+
+/*
+ * This is PXA's sched_clock implementation. This has a resolution
+ * of at least 308 ns and a maximum value of 208 days.
+ *
+ * The return value is guaranteed to be monotonic in that range as
+ * long as there is always less than 582 seconds between successive
+ * calls to sched_clock() which should always be the case in practice.
+ */
+
+#define timer_readl(reg) readl_relaxed(timer_base + (reg))
+#define timer_writel(val, reg) writel_relaxed((val), timer_base + (reg))
+
+static void __iomem *timer_base;
+
+static u64 notrace pxa_read_sched_clock(void)
+{
+	return timer_readl(OSCR);
+}
+
+
+#define MIN_OSCR_DELTA 16
+
+static irqreturn_t
+pxa_ost0_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *c = dev_id;
+
+	/* Disarm the compare/match, signal the event. */
+	timer_writel(timer_readl(OIER) & ~OIER_E0, OIER);
+	timer_writel(OSSR_M0, OSSR);
+	c->event_handler(c);
+
+	return IRQ_HANDLED;
+}
+
+static int
+pxa_osmr0_set_next_event(unsigned long delta, struct clock_event_device *dev)
+{
+	unsigned long next, oscr;
+
+	timer_writel(timer_readl(OIER) | OIER_E0, OIER);
+	next = timer_readl(OSCR) + delta;
+	timer_writel(next, OSMR0);
+	oscr = timer_readl(OSCR);
+
+	return (signed)(next - oscr) <= MIN_OSCR_DELTA ? -ETIME : 0;
+}
+
+static int pxa_osmr0_shutdown(struct clock_event_device *evt)
+{
+	/* initializing, released, or preparing for suspend */
+	timer_writel(timer_readl(OIER) & ~OIER_E0, OIER);
+	timer_writel(OSSR_M0, OSSR);
+	return 0;
+}
+
+#ifdef CONFIG_PM
+static unsigned long osmr[4], oier, oscr;
+
+static void pxa_timer_suspend(struct clock_event_device *cedev)
+{
+	osmr[0] = timer_readl(OSMR0);
+	osmr[1] = timer_readl(OSMR1);
+	osmr[2] = timer_readl(OSMR2);
+	osmr[3] = timer_readl(OSMR3);
+	oier = timer_readl(OIER);
+	oscr = timer_readl(OSCR);
+}
+
+static void pxa_timer_resume(struct clock_event_device *cedev)
+{
+	/*
+	 * Ensure that we have at least MIN_OSCR_DELTA between match
+	 * register 0 and the OSCR, to guarantee that we will receive
+	 * the one-shot timer interrupt.  We adjust OSMR0 in preference
+	 * to OSCR to guarantee that OSCR is monotonically incrementing.
+	 */
+	if (osmr[0] - oscr < MIN_OSCR_DELTA)
+		osmr[0] += MIN_OSCR_DELTA;
+
+	timer_writel(osmr[0], OSMR0);
+	timer_writel(osmr[1], OSMR1);
+	timer_writel(osmr[2], OSMR2);
+	timer_writel(osmr[3], OSMR3);
+	timer_writel(oier, OIER);
+	timer_writel(oscr, OSCR);
+}
+#else
+#define pxa_timer_suspend NULL
+#define pxa_timer_resume NULL
+#endif
+
+static struct clock_event_device ckevt_pxa_osmr0 = {
+	.name			= "osmr0",
+	.features		= CLOCK_EVT_FEAT_ONESHOT,
+	.rating			= 200,
+	.set_next_event		= pxa_osmr0_set_next_event,
+	.set_state_shutdown	= pxa_osmr0_shutdown,
+	.set_state_oneshot	= pxa_osmr0_shutdown,
+	.suspend		= pxa_timer_suspend,
+	.resume			= pxa_timer_resume,
+};
+
+static struct irqaction pxa_ost0_irq = {
+	.name		= "ost0",
+	.flags		= IRQF_TIMER | IRQF_IRQPOLL,
+	.handler	= pxa_ost0_interrupt,
+	.dev_id		= &ckevt_pxa_osmr0,
+};
+
+static int __init pxa_timer_common_init(int irq, unsigned long clock_tick_rate)
+{
+	int ret;
+
+	timer_writel(0, OIER);
+	timer_writel(OSSR_M0 | OSSR_M1 | OSSR_M2 | OSSR_M3, OSSR);
+
+	sched_clock_register(pxa_read_sched_clock, 32, clock_tick_rate);
+
+	ckevt_pxa_osmr0.cpumask = cpumask_of(0);
+
+	ret = setup_irq(irq, &pxa_ost0_irq);
+	if (ret) {
+		pr_err("Failed to setup irq\n");
+		return ret;
+	}
+
+	ret = clocksource_mmio_init(timer_base + OSCR, "oscr0", clock_tick_rate, 200,
+				    32, clocksource_mmio_readl_up);
+	if (ret) {
+		pr_err("Failed to init clocksource\n");
+		return ret;
+	}
+
+	clockevents_config_and_register(&ckevt_pxa_osmr0, clock_tick_rate,
+					MIN_OSCR_DELTA * 2, 0x7fffffff);
+
+	return 0;
+}
+
+static int __init pxa_timer_dt_init(struct device_node *np)
+{
+	struct clk *clk;
+	int irq, ret;
+
+	/* timer registers are shared with watchdog timer */
+	timer_base = of_iomap(np, 0);
+	if (!timer_base) {
+		pr_err("%s: unable to map resource\n", np->name);
+		return -ENXIO;
+	}
+
+	clk = of_clk_get(np, 0);
+	if (IS_ERR(clk)) {
+		pr_crit("%s: unable to get clk\n", np->name);
+		return PTR_ERR(clk);
+	}
+
+	ret = clk_prepare_enable(clk);
+	if (ret) {
+		pr_crit("Failed to prepare clock\n");
+		return ret;
+	}
+
+	/* we are only interested in OS-timer0 irq */
+	irq = irq_of_parse_and_map(np, 0);
+	if (irq <= 0) {
+		pr_crit("%s: unable to parse OS-timer0 irq\n", np->name);
+		return -EINVAL;
+	}
+
+	return pxa_timer_common_init(irq, clk_get_rate(clk));
+}
+TIMER_OF_DECLARE(pxa_timer, "marvell,pxa-timer", pxa_timer_dt_init);
+
+/*
+ * Legacy timer init for non device-tree boards.
+ */
+void __init pxa_timer_nodt_init(int irq, void __iomem *base)
+{
+	struct clk *clk;
+
+	timer_base = base;
+	clk = clk_get(NULL, "OSTIMER0");
+	if (clk && !IS_ERR(clk)) {
+		clk_prepare_enable(clk);
+		pxa_timer_common_init(irq, clk_get_rate(clk));
+	} else {
+		pr_crit("%s: unable to get clk\n", __func__);
+	}
+}

drivers/clocksource/qcom-timer.c

@@ -0,0 +1,258 @@
+/*
+ *
+ * Copyright (C) 2007 Google, Inc.
+ * Copyright (c) 2009-2012,2014, The Linux Foundation. All rights reserved.
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/cpu.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+
+#include <asm/delay.h>
+
+#define TIMER_MATCH_VAL			0x0000
+#define TIMER_COUNT_VAL			0x0004
+#define TIMER_ENABLE			0x0008
+#define TIMER_ENABLE_CLR_ON_MATCH_EN	BIT(1)
+#define TIMER_ENABLE_EN			BIT(0)
+#define TIMER_CLEAR			0x000C
+#define DGT_CLK_CTL			0x10
+#define DGT_CLK_CTL_DIV_4		0x3
+#define TIMER_STS_GPT0_CLR_PEND		BIT(10)
+
+#define GPT_HZ 32768
+
+static void __iomem *event_base;
+static void __iomem *sts_base;
+
+static irqreturn_t msm_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+	/* Stop the timer tick */
+	if (clockevent_state_oneshot(evt)) {
+		u32 ctrl = readl_relaxed(event_base + TIMER_ENABLE);
+		ctrl &= ~TIMER_ENABLE_EN;
+		writel_relaxed(ctrl, event_base + TIMER_ENABLE);
+	}
+	evt->event_handler(evt);
+	return IRQ_HANDLED;
+}
+
+static int msm_timer_set_next_event(unsigned long cycles,
+				    struct clock_event_device *evt)
+{
+	u32 ctrl = readl_relaxed(event_base + TIMER_ENABLE);
+
+	ctrl &= ~TIMER_ENABLE_EN;
+	writel_relaxed(ctrl, event_base + TIMER_ENABLE);
+
+	writel_relaxed(ctrl, event_base + TIMER_CLEAR);
+	writel_relaxed(cycles, event_base + TIMER_MATCH_VAL);
+
+	if (sts_base)
+		while (readl_relaxed(sts_base) & TIMER_STS_GPT0_CLR_PEND)
+			cpu_relax();
+
+	writel_relaxed(ctrl | TIMER_ENABLE_EN, event_base + TIMER_ENABLE);
+	return 0;
+}
+
+static int msm_timer_shutdown(struct clock_event_device *evt)
+{
+	u32 ctrl;
+
+	ctrl = readl_relaxed(event_base + TIMER_ENABLE);
+	ctrl &= ~(TIMER_ENABLE_EN | TIMER_ENABLE_CLR_ON_MATCH_EN);
+	writel_relaxed(ctrl, event_base + TIMER_ENABLE);
+	return 0;
+}
+
+static struct clock_event_device __percpu *msm_evt;
+
+static void __iomem *source_base;
+
+static notrace u64 msm_read_timer_count(struct clocksource *cs)
+{
+	return readl_relaxed(source_base + TIMER_COUNT_VAL);
+}
+
+static struct clocksource msm_clocksource = {
+	.name	= "dg_timer",
+	.rating	= 300,
+	.read	= msm_read_timer_count,
+	.mask	= CLOCKSOURCE_MASK(32),
+	.flags	= CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static int msm_timer_irq;
+static int msm_timer_has_ppi;
+
+static int msm_local_timer_starting_cpu(unsigned int cpu)
+{
+	struct clock_event_device *evt = per_cpu_ptr(msm_evt, cpu);
+	int err;
+
+	evt->irq = msm_timer_irq;
+	evt->name = "msm_timer";
+	evt->features = CLOCK_EVT_FEAT_ONESHOT;
+	evt->rating = 200;
+	evt->set_state_shutdown = msm_timer_shutdown;
+	evt->set_state_oneshot = msm_timer_shutdown;
+	evt->tick_resume = msm_timer_shutdown;
+	evt->set_next_event = msm_timer_set_next_event;
+	evt->cpumask = cpumask_of(cpu);
+
+	clockevents_config_and_register(evt, GPT_HZ, 4, 0xffffffff);
+
+	if (msm_timer_has_ppi) {
+		enable_percpu_irq(evt->irq, IRQ_TYPE_EDGE_RISING);
+	} else {
+		err = request_irq(evt->irq, msm_timer_interrupt,
+				IRQF_TIMER | IRQF_NOBALANCING |
+				IRQF_TRIGGER_RISING, "gp_timer", evt);
+		if (err)
+			pr_err("request_irq failed\n");
+	}
+
+	return 0;
+}
+
+static int msm_local_timer_dying_cpu(unsigned int cpu)
+{
+	struct clock_event_device *evt = per_cpu_ptr(msm_evt, cpu);
+
+	evt->set_state_shutdown(evt);
+	disable_percpu_irq(evt->irq);
+	return 0;
+}
+
+static u64 notrace msm_sched_clock_read(void)
+{
+	return msm_clocksource.read(&msm_clocksource);
+}
+
+static unsigned long msm_read_current_timer(void)
+{
+	return msm_clocksource.read(&msm_clocksource);
+}
+
+static struct delay_timer msm_delay_timer = {
+	.read_current_timer = msm_read_current_timer,
+};
+
+static int __init msm_timer_init(u32 dgt_hz, int sched_bits, int irq,
+				  bool percpu)
+{
+	struct clocksource *cs = &msm_clocksource;
+	int res = 0;
+
+	msm_timer_irq = irq;
+	msm_timer_has_ppi = percpu;
+
+	msm_evt = alloc_percpu(struct clock_event_device);
+	if (!msm_evt) {
+		pr_err("memory allocation failed for clockevents\n");
+		goto err;
+	}
+
+	if (percpu)
+		res = request_percpu_irq(irq, msm_timer_interrupt,
+					 "gp_timer", msm_evt);
+
+	if (res) {
+		pr_err("request_percpu_irq failed\n");
+	} else {
+		/* Install and invoke hotplug callbacks */
+		res = cpuhp_setup_state(CPUHP_AP_QCOM_TIMER_STARTING,
+					"clockevents/qcom/timer:starting",
+					msm_local_timer_starting_cpu,
+					msm_local_timer_dying_cpu);
+		if (res) {
+			free_percpu_irq(irq, msm_evt);
+			goto err;
+		}
+	}
+
+err:
+	writel_relaxed(TIMER_ENABLE_EN, source_base + TIMER_ENABLE);
+	res = clocksource_register_hz(cs, dgt_hz);
+	if (res)
+		pr_err("clocksource_register failed\n");
+	sched_clock_register(msm_sched_clock_read, sched_bits, dgt_hz);
+	msm_delay_timer.freq = dgt_hz;
+	register_current_timer_delay(&msm_delay_timer);
+
+	return res;
+}
+
+static int __init msm_dt_timer_init(struct device_node *np)
+{
+	u32 freq;
+	int irq, ret;
+	struct resource res;
+	u32 percpu_offset;
+	void __iomem *base;
+	void __iomem *cpu0_base;
+
+	base = of_iomap(np, 0);
+	if (!base) {
+		pr_err("Failed to map event base\n");
+		return -ENXIO;
+	}
+
+	/* We use GPT0 for the clockevent */
+	irq = irq_of_parse_and_map(np, 1);
+	if (irq <= 0) {
+		pr_err("Can't get irq\n");
+		return -EINVAL;
+	}
+
+	/* We use CPU0's DGT for the clocksource */
+	if (of_property_read_u32(np, "cpu-offset", &percpu_offset))
+		percpu_offset = 0;
+
+	ret = of_address_to_resource(np, 0, &res);
+	if (ret) {
+		pr_err("Failed to parse DGT resource\n");
+		return ret;
+	}
+
+	cpu0_base = ioremap(res.start + percpu_offset, resource_size(&res));
+	if (!cpu0_base) {
+		pr_err("Failed to map source base\n");
+		return -EINVAL;
+	}
+
+	if (of_property_read_u32(np, "clock-frequency", &freq)) {
+		pr_err("Unknown frequency\n");
+		return -EINVAL;
+	}
+
+	event_base = base + 0x4;
+	sts_base = base + 0x88;
+	source_base = cpu0_base + 0x24;
+	freq /= 4;
+	writel_relaxed(DGT_CLK_CTL_DIV_4, source_base + DGT_CLK_CTL);
+
+	return msm_timer_init(freq, 32, irq, !!percpu_offset);
+}
+TIMER_OF_DECLARE(kpss_timer, "qcom,kpss-timer", msm_dt_timer_init);
+TIMER_OF_DECLARE(scss_timer, "qcom,scss-timer", msm_dt_timer_init);

drivers/clocksource/renesas-ostm.c

@@ -0,0 +1,265 @@
+/*
+ * Renesas Timer Support - OSTM
+ *
+ * Copyright (C) 2017 Renesas Electronics America, Inc.
+ * Copyright (C) 2017 Chris Brandt
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/sched_clock.h>
+#include <linux/slab.h>
+
+/*
+ * The OSTM contains independent channels.
+ * The first OSTM channel probed will be set up as a free running
+ * clocksource. Additionally we will use this clocksource for the system
+ * schedule timer sched_clock().
+ *
+ * The second (or more) channel probed will be set up as an interrupt
+ * driven clock event.
+ */
+
+struct ostm_device {
+	void __iomem *base;
+	unsigned long ticks_per_jiffy;
+	struct clock_event_device ced;
+};
+
+static void __iomem *system_clock;	/* For sched_clock() */
+
+/* OSTM REGISTERS */
+#define	OSTM_CMP		0x000	/* RW,32 */
+#define	OSTM_CNT		0x004	/* R,32 */
+#define	OSTM_TE			0x010	/* R,8 */
+#define	OSTM_TS			0x014	/* W,8 */
+#define	OSTM_TT			0x018	/* W,8 */
+#define	OSTM_CTL		0x020	/* RW,8 */
+
+#define	TE			0x01
+#define	TS			0x01
+#define	TT			0x01
+#define	CTL_PERIODIC		0x00
+#define	CTL_ONESHOT		0x02
+#define	CTL_FREERUN		0x02
+
+static struct ostm_device *ced_to_ostm(struct clock_event_device *ced)
+{
+	return container_of(ced, struct ostm_device, ced);
+}
+
+static void ostm_timer_stop(struct ostm_device *ostm)
+{
+	if (readb(ostm->base + OSTM_TE) & TE) {
+		writeb(TT, ostm->base + OSTM_TT);
+
+		/*
+		 * Read back the register simply to confirm the write operation
+		 * has completed since I/O writes can sometimes get queued by
+		 * the bus architecture.
+		 */
+		while (readb(ostm->base + OSTM_TE) & TE)
+			;
+	}
+}
+
+static int __init ostm_init_clksrc(struct ostm_device *ostm, unsigned long rate)
+{
+	/*
+	 * irq not used (clock sources don't use interrupts)
+	 */
+
+	ostm_timer_stop(ostm);
+
+	writel(0, ostm->base + OSTM_CMP);
+	writeb(CTL_FREERUN, ostm->base + OSTM_CTL);
+	writeb(TS, ostm->base + OSTM_TS);
+
+	return clocksource_mmio_init(ostm->base + OSTM_CNT,
+			"ostm", rate,
+			300, 32, clocksource_mmio_readl_up);
+}
+
+static u64 notrace ostm_read_sched_clock(void)
+{
+	return readl(system_clock);
+}
+
+static void __init ostm_init_sched_clock(struct ostm_device *ostm,
+			unsigned long rate)
+{
+	system_clock = ostm->base + OSTM_CNT;
+	sched_clock_register(ostm_read_sched_clock, 32, rate);
+}
+
+static int ostm_clock_event_next(unsigned long delta,
+				     struct clock_event_device *ced)
+{
+	struct ostm_device *ostm = ced_to_ostm(ced);
+
+	ostm_timer_stop(ostm);
+
+	writel(delta, ostm->base + OSTM_CMP);
+	writeb(CTL_ONESHOT, ostm->base + OSTM_CTL);
+	writeb(TS, ostm->base + OSTM_TS);
+
+	return 0;
+}
+
+static int ostm_shutdown(struct clock_event_device *ced)
+{
+	struct ostm_device *ostm = ced_to_ostm(ced);
+
+	ostm_timer_stop(ostm);
+
+	return 0;
+}
+static int ostm_set_periodic(struct clock_event_device *ced)
+{
+	struct ostm_device *ostm = ced_to_ostm(ced);
+
+	if (clockevent_state_oneshot(ced) || clockevent_state_periodic(ced))
+		ostm_timer_stop(ostm);
+
+	writel(ostm->ticks_per_jiffy - 1, ostm->base + OSTM_CMP);
+	writeb(CTL_PERIODIC, ostm->base + OSTM_CTL);
+	writeb(TS, ostm->base + OSTM_TS);
+
+	return 0;
+}
+
+static int ostm_set_oneshot(struct clock_event_device *ced)
+{
+	struct ostm_device *ostm = ced_to_ostm(ced);
+
+	ostm_timer_stop(ostm);
+
+	return 0;
+}
+
+static irqreturn_t ostm_timer_interrupt(int irq, void *dev_id)
+{
+	struct ostm_device *ostm = dev_id;
+
+	if (clockevent_state_oneshot(&ostm->ced))
+		ostm_timer_stop(ostm);
+
+	/* notify clockevent layer */
+	if (ostm->ced.event_handler)
+		ostm->ced.event_handler(&ostm->ced);
+
+	return IRQ_HANDLED;
+}
+
+static int __init ostm_init_clkevt(struct ostm_device *ostm, int irq,
+			unsigned long rate)
+{
+	struct clock_event_device *ced = &ostm->ced;
+	int ret = -ENXIO;
+
+	ret = request_irq(irq, ostm_timer_interrupt,
+			  IRQF_TIMER | IRQF_IRQPOLL,
+			  "ostm", ostm);
+	if (ret) {
+		pr_err("ostm: failed to request irq\n");
+		return ret;
+	}
+
+	ced->name = "ostm";
+	ced->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC;
+	ced->set_state_shutdown = ostm_shutdown;
+	ced->set_state_periodic = ostm_set_periodic;
+	ced->set_state_oneshot = ostm_set_oneshot;
+	ced->set_next_event = ostm_clock_event_next;
+	ced->shift = 32;
+	ced->rating = 300;
+	ced->cpumask = cpumask_of(0);
+	clockevents_config_and_register(ced, rate, 0xf, 0xffffffff);
+
+	return 0;
+}
+
+static int __init ostm_init(struct device_node *np)
+{
+	struct ostm_device *ostm;
+	int ret = -EFAULT;
+	struct clk *ostm_clk = NULL;
+	int irq;
+	unsigned long rate;
+
+	ostm = kzalloc(sizeof(*ostm), GFP_KERNEL);
+	if (!ostm)
+		return -ENOMEM;
+
+	ostm->base = of_iomap(np, 0);
+	if (!ostm->base) {
+		pr_err("ostm: failed to remap I/O memory\n");
+		goto err;
+	}
+
+	irq = irq_of_parse_and_map(np, 0);
+	if (irq < 0) {
+		pr_err("ostm: Failed to get irq\n");
+		goto err;
+	}
+
+	ostm_clk = of_clk_get(np, 0);
+	if (IS_ERR(ostm_clk)) {
+		pr_err("ostm: Failed to get clock\n");
+		ostm_clk = NULL;
+		goto err;
+	}
+
+	ret = clk_prepare_enable(ostm_clk);
+	if (ret) {
+		pr_err("ostm: Failed to enable clock\n");
+		goto err;
+	}
+
+	rate = clk_get_rate(ostm_clk);
+	ostm->ticks_per_jiffy = (rate + HZ / 2) / HZ;
+
+	/*
+	 * First probed device will be used as system clocksource. Any
+	 * additional devices will be used as clock events.
+	 */
+	if (!system_clock) {
+		ret = ostm_init_clksrc(ostm, rate);
+
+		if (!ret) {
+			ostm_init_sched_clock(ostm, rate);
+			pr_info("ostm: used for clocksource\n");
+		}
+
+	} else {
+		ret = ostm_init_clkevt(ostm, irq, rate);
+
+		if (!ret)
+			pr_info("ostm: used for clock events\n");
+	}
+
+err:
+	if (ret) {
+		clk_disable_unprepare(ostm_clk);
+		iounmap(ostm->base);
+		kfree(ostm);
+		return ret;
+	}
+
+	return 0;
+}
+
+TIMER_OF_DECLARE(ostm, "renesas,ostm", ostm_init);

drivers/clocksource/riscv_timer.c

@@ -0,0 +1,105 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ */
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/cpu.h>
+#include <linux/delay.h>
+#include <linux/irq.h>
+#include <asm/sbi.h>
+
+/*
+ * All RISC-V systems have a timer attached to every hart.  These timers can be
+ * read by the 'rdcycle' pseudo instruction, and can use the SBI to setup
+ * events.  In order to abstract the architecture-specific timer reading and
+ * setting functions away from the clock event insertion code, we provide
+ * function pointers to the clockevent subsystem that perform two basic
+ * operations: rdtime() reads the timer on the current CPU, and
+ * next_event(delta) sets the next timer event to 'delta' cycles in the future.
+ * As the timers are inherently a per-cpu resource, these callbacks perform
+ * operations on the current hart.  There is guaranteed to be exactly one timer
+ * per hart on all RISC-V systems.
+ */
+
+static int riscv_clock_next_event(unsigned long delta,
+		struct clock_event_device *ce)
+{
+	csr_set(sie, SIE_STIE);
+	sbi_set_timer(get_cycles64() + delta);
+	return 0;
+}
+
+static DEFINE_PER_CPU(struct clock_event_device, riscv_clock_event) = {
+	.name			= "riscv_timer_clockevent",
+	.features		= CLOCK_EVT_FEAT_ONESHOT,
+	.rating			= 100,
+	.set_next_event		= riscv_clock_next_event,
+};
+
+/*
+ * It is guaranteed that all the timers across all the harts are synchronized
+ * within one tick of each other, so while this could technically go
+ * backwards when hopping between CPUs, practically it won't happen.
+ */
+static unsigned long long riscv_clocksource_rdtime(struct clocksource *cs)
+{
+	return get_cycles64();
+}
+
+static DEFINE_PER_CPU(struct clocksource, riscv_clocksource) = {
+	.name		= "riscv_clocksource",
+	.rating		= 300,
+	.mask		= CLOCKSOURCE_MASK(BITS_PER_LONG),
+	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
+	.read		= riscv_clocksource_rdtime,
+};
+
+static int riscv_timer_starting_cpu(unsigned int cpu)
+{
+	struct clock_event_device *ce = per_cpu_ptr(&riscv_clock_event, cpu);
+
+	ce->cpumask = cpumask_of(cpu);
+	clockevents_config_and_register(ce, riscv_timebase, 100, 0x7fffffff);
+
+	csr_set(sie, SIE_STIE);
+	return 0;
+}
+
+static int riscv_timer_dying_cpu(unsigned int cpu)
+{
+	csr_clear(sie, SIE_STIE);
+	return 0;
+}
+
+/* called directly from the low-level interrupt handler */
+void riscv_timer_interrupt(void)
+{
+	struct clock_event_device *evdev = this_cpu_ptr(&riscv_clock_event);
+
+	csr_clear(sie, SIE_STIE);
+	evdev->event_handler(evdev);
+}
+
+static int __init riscv_timer_init_dt(struct device_node *n)
+{
+	int cpu_id = riscv_of_processor_hart(n), error;
+	struct clocksource *cs;
+
+	if (cpu_id != smp_processor_id())
+		return 0;
+
+	cs = per_cpu_ptr(&riscv_clocksource, cpu_id);
+	clocksource_register_hz(cs, riscv_timebase);
+
+	error = cpuhp_setup_state(CPUHP_AP_RISCV_TIMER_STARTING,
+			 "clockevents/riscv/timer:starting",
+			 riscv_timer_starting_cpu, riscv_timer_dying_cpu);
+	if (error)
+		pr_err("RISCV timer register failed [%d] for cpu = [%d]\n",
+		       error, cpu_id);
+	return error;
+}
+
+TIMER_OF_DECLARE(riscv_timer, "riscv", riscv_timer_init_dt);

drivers/clocksource/rockchip_timer.c

@@ -0,0 +1,307 @@
+/*
+ * Rockchip timer support
+ *
+ * Copyright (C) Daniel Lezcano <daniel.lezcano@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/sched_clock.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define TIMER_NAME "rk_timer"
+
+#define TIMER_LOAD_COUNT0	0x00
+#define TIMER_LOAD_COUNT1	0x04
+#define TIMER_CURRENT_VALUE0	0x08
+#define TIMER_CURRENT_VALUE1	0x0C
+#define TIMER_CONTROL_REG3288	0x10
+#define TIMER_CONTROL_REG3399	0x1c
+#define TIMER_INT_STATUS	0x18
+
+#define TIMER_DISABLE		0x0
+#define TIMER_ENABLE		0x1
+#define TIMER_MODE_FREE_RUNNING			(0 << 1)
+#define TIMER_MODE_USER_DEFINED_COUNT		(1 << 1)
+#define TIMER_INT_UNMASK			(1 << 2)
+
+struct rk_timer {
+	void __iomem *base;
+	void __iomem *ctrl;
+	struct clk *clk;
+	struct clk *pclk;
+	u32 freq;
+	int irq;
+};
+
+struct rk_clkevt {
+	struct clock_event_device ce;
+	struct rk_timer timer;
+};
+
+static struct rk_clkevt *rk_clkevt;
+static struct rk_timer *rk_clksrc;
+
+static inline struct rk_timer *rk_timer(struct clock_event_device *ce)
+{
+	return &container_of(ce, struct rk_clkevt, ce)->timer;
+}
+
+static inline void rk_timer_disable(struct rk_timer *timer)
+{
+	writel_relaxed(TIMER_DISABLE, timer->ctrl);
+}
+
+static inline void rk_timer_enable(struct rk_timer *timer, u32 flags)
+{
+	writel_relaxed(TIMER_ENABLE | flags, timer->ctrl);
+}
+
+static void rk_timer_update_counter(unsigned long cycles,
+				    struct rk_timer *timer)
+{
+	writel_relaxed(cycles, timer->base + TIMER_LOAD_COUNT0);
+	writel_relaxed(0, timer->base + TIMER_LOAD_COUNT1);
+}
+
+static void rk_timer_interrupt_clear(struct rk_timer *timer)
+{
+	writel_relaxed(1, timer->base + TIMER_INT_STATUS);
+}
+
+static inline int rk_timer_set_next_event(unsigned long cycles,
+					  struct clock_event_device *ce)
+{
+	struct rk_timer *timer = rk_timer(ce);
+
+	rk_timer_disable(timer);
+	rk_timer_update_counter(cycles, timer);
+	rk_timer_enable(timer, TIMER_MODE_USER_DEFINED_COUNT |
+			       TIMER_INT_UNMASK);
+	return 0;
+}
+
+static int rk_timer_shutdown(struct clock_event_device *ce)
+{
+	struct rk_timer *timer = rk_timer(ce);
+
+	rk_timer_disable(timer);
+	return 0;
+}
+
+static int rk_timer_set_periodic(struct clock_event_device *ce)
+{
+	struct rk_timer *timer = rk_timer(ce);
+
+	rk_timer_disable(timer);
+	rk_timer_update_counter(timer->freq / HZ - 1, timer);
+	rk_timer_enable(timer, TIMER_MODE_FREE_RUNNING | TIMER_INT_UNMASK);
+	return 0;
+}
+
+static irqreturn_t rk_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *ce = dev_id;
+	struct rk_timer *timer = rk_timer(ce);
+
+	rk_timer_interrupt_clear(timer);
+
+	if (clockevent_state_oneshot(ce))
+		rk_timer_disable(timer);
+
+	ce->event_handler(ce);
+
+	return IRQ_HANDLED;
+}
+
+static u64 notrace rk_timer_sched_read(void)
+{
+	return ~readl_relaxed(rk_clksrc->base + TIMER_CURRENT_VALUE0);
+}
+
+static int __init
+rk_timer_probe(struct rk_timer *timer, struct device_node *np)
+{
+	struct clk *timer_clk;
+	struct clk *pclk;
+	int ret = -EINVAL, irq;
+	u32 ctrl_reg = TIMER_CONTROL_REG3288;
+
+	timer->base = of_iomap(np, 0);
+	if (!timer->base) {
+		pr_err("Failed to get base address for '%s'\n", TIMER_NAME);
+		return -ENXIO;
+	}
+
+	if (of_device_is_compatible(np, "rockchip,rk3399-timer"))
+		ctrl_reg = TIMER_CONTROL_REG3399;
+
+	timer->ctrl = timer->base + ctrl_reg;
+
+	pclk = of_clk_get_by_name(np, "pclk");
+	if (IS_ERR(pclk)) {
+		ret = PTR_ERR(pclk);
+		pr_err("Failed to get pclk for '%s'\n", TIMER_NAME);
+		goto out_unmap;
+	}
+
+	ret = clk_prepare_enable(pclk);
+	if (ret) {
+		pr_err("Failed to enable pclk for '%s'\n", TIMER_NAME);
+		goto out_unmap;
+	}
+	timer->pclk = pclk;
+
+	timer_clk = of_clk_get_by_name(np, "timer");
+	if (IS_ERR(timer_clk)) {
+		ret = PTR_ERR(timer_clk);
+		pr_err("Failed to get timer clock for '%s'\n", TIMER_NAME);
+		goto out_timer_clk;
+	}
+
+	ret = clk_prepare_enable(timer_clk);
+	if (ret) {
+		pr_err("Failed to enable timer clock\n");
+		goto out_timer_clk;
+	}
+	timer->clk = timer_clk;
+
+	timer->freq = clk_get_rate(timer_clk);
+
+	irq = irq_of_parse_and_map(np, 0);
+	if (!irq) {
+		ret = -EINVAL;
+		pr_err("Failed to map interrupts for '%s'\n", TIMER_NAME);
+		goto out_irq;
+	}
+	timer->irq = irq;
+
+	rk_timer_interrupt_clear(timer);
+	rk_timer_disable(timer);
+	return 0;
+
+out_irq:
+	clk_disable_unprepare(timer_clk);
+out_timer_clk:
+	clk_disable_unprepare(pclk);
+out_unmap:
+	iounmap(timer->base);
+
+	return ret;
+}
+
+static void __init rk_timer_cleanup(struct rk_timer *timer)
+{
+	clk_disable_unprepare(timer->clk);
+	clk_disable_unprepare(timer->pclk);
+	iounmap(timer->base);
+}
+
+static int __init rk_clkevt_init(struct device_node *np)
+{
+	struct clock_event_device *ce;
+	int ret = -EINVAL;
+
+	rk_clkevt = kzalloc(sizeof(struct rk_clkevt), GFP_KERNEL);
+	if (!rk_clkevt) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	ret = rk_timer_probe(&rk_clkevt->timer, np);
+	if (ret)
+		goto out_probe;
+
+	ce = &rk_clkevt->ce;
+	ce->name = TIMER_NAME;
+	ce->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT |
+		       CLOCK_EVT_FEAT_DYNIRQ;
+	ce->set_next_event = rk_timer_set_next_event;
+	ce->set_state_shutdown = rk_timer_shutdown;
+	ce->set_state_periodic = rk_timer_set_periodic;
+	ce->irq = rk_clkevt->timer.irq;
+	ce->cpumask = cpu_possible_mask;
+	ce->rating = 250;
+
+	ret = request_irq(rk_clkevt->timer.irq, rk_timer_interrupt, IRQF_TIMER,
+			  TIMER_NAME, ce);
+	if (ret) {
+		pr_err("Failed to initialize '%s': %d\n",
+			TIMER_NAME, ret);
+		goto out_irq;
+	}
+
+	clockevents_config_and_register(&rk_clkevt->ce,
+					rk_clkevt->timer.freq, 1, UINT_MAX);
+	return 0;
+
+out_irq:
+	rk_timer_cleanup(&rk_clkevt->timer);
+out_probe:
+	kfree(rk_clkevt);
+out:
+	/* Leave rk_clkevt not NULL to prevent future init */
+	rk_clkevt = ERR_PTR(ret);
+	return ret;
+}
+
+static int __init rk_clksrc_init(struct device_node *np)
+{
+	int ret = -EINVAL;
+
+	rk_clksrc = kzalloc(sizeof(struct rk_timer), GFP_KERNEL);
+	if (!rk_clksrc) {
+		ret = -ENOMEM;
+		goto out;
+	}
+
+	ret = rk_timer_probe(rk_clksrc, np);
+	if (ret)
+		goto out_probe;
+
+	rk_timer_update_counter(UINT_MAX, rk_clksrc);
+	rk_timer_enable(rk_clksrc, 0);
+
+	ret = clocksource_mmio_init(rk_clksrc->base + TIMER_CURRENT_VALUE0,
+		TIMER_NAME, rk_clksrc->freq, 250, 32,
+		clocksource_mmio_readl_down);
+	if (ret) {
+		pr_err("Failed to register clocksource\n");
+		goto out_clocksource;
+	}
+
+	sched_clock_register(rk_timer_sched_read, 32, rk_clksrc->freq);
+	return 0;
+
+out_clocksource:
+	rk_timer_cleanup(rk_clksrc);
+out_probe:
+	kfree(rk_clksrc);
+out:
+	/* Leave rk_clksrc not NULL to prevent future init */
+	rk_clksrc = ERR_PTR(ret);
+	return ret;
+}
+
+static int __init rk_timer_init(struct device_node *np)
+{
+	if (!rk_clkevt)
+		return rk_clkevt_init(np);
+
+	if (!rk_clksrc)
+		return rk_clksrc_init(np);
+
+	pr_err("Too many timer definitions for '%s'\n", TIMER_NAME);
+	return -EINVAL;
+}
+
+TIMER_OF_DECLARE(rk3288_timer, "rockchip,rk3288-timer", rk_timer_init);
+TIMER_OF_DECLARE(rk3399_timer, "rockchip,rk3399-timer", rk_timer_init);

drivers/clocksource/samsung_pwm_timer.c

@@ -0,0 +1,509 @@
+/*
+ * Copyright (c) 2011 Samsung Electronics Co., Ltd.
+ *		http://www.samsung.com/
+ *
+ * samsung - Common hr-timer support (s3c and s5p)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+*/
+
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/list.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/sched_clock.h>
+
+#include <clocksource/samsung_pwm.h>
+
+
+/*
+ * Clocksource driver
+ */
+
+#define REG_TCFG0			0x00
+#define REG_TCFG1			0x04
+#define REG_TCON			0x08
+#define REG_TINT_CSTAT			0x44
+
+#define REG_TCNTB(chan)			(0x0c + 12 * (chan))
+#define REG_TCMPB(chan)			(0x10 + 12 * (chan))
+
+#define TCFG0_PRESCALER_MASK		0xff
+#define TCFG0_PRESCALER1_SHIFT		8
+
+#define TCFG1_SHIFT(x)	  		((x) * 4)
+#define TCFG1_MUX_MASK	  		0xf
+
+/*
+ * Each channel occupies 4 bits in TCON register, but there is a gap of 4
+ * bits (one channel) after channel 0, so channels have different numbering
+ * when accessing TCON register.
+ *
+ * In addition, the location of autoreload bit for channel 4 (TCON channel 5)
+ * in its set of bits is 2 as opposed to 3 for other channels.
+ */
+#define TCON_START(chan)		(1 << (4 * (chan) + 0))
+#define TCON_MANUALUPDATE(chan)		(1 << (4 * (chan) + 1))
+#define TCON_INVERT(chan)		(1 << (4 * (chan) + 2))
+#define _TCON_AUTORELOAD(chan)		(1 << (4 * (chan) + 3))
+#define _TCON_AUTORELOAD4(chan)		(1 << (4 * (chan) + 2))
+#define TCON_AUTORELOAD(chan)		\
+	((chan < 5) ? _TCON_AUTORELOAD(chan) : _TCON_AUTORELOAD4(chan))
+
+DEFINE_SPINLOCK(samsung_pwm_lock);
+EXPORT_SYMBOL(samsung_pwm_lock);
+
+struct samsung_pwm_clocksource {
+	void __iomem *base;
+	void __iomem *source_reg;
+	unsigned int irq[SAMSUNG_PWM_NUM];
+	struct samsung_pwm_variant variant;
+
+	struct clk *timerclk;
+
+	unsigned int event_id;
+	unsigned int source_id;
+	unsigned int tcnt_max;
+	unsigned int tscaler_div;
+	unsigned int tdiv;
+
+	unsigned long clock_count_per_tick;
+};
+
+static struct samsung_pwm_clocksource pwm;
+
+static void samsung_timer_set_prescale(unsigned int channel, u16 prescale)
+{
+	unsigned long flags;
+	u8 shift = 0;
+	u32 reg;
+
+	if (channel >= 2)
+		shift = TCFG0_PRESCALER1_SHIFT;
+
+	spin_lock_irqsave(&samsung_pwm_lock, flags);
+
+	reg = readl(pwm.base + REG_TCFG0);
+	reg &= ~(TCFG0_PRESCALER_MASK << shift);
+	reg |= (prescale - 1) << shift;
+	writel(reg, pwm.base + REG_TCFG0);
+
+	spin_unlock_irqrestore(&samsung_pwm_lock, flags);
+}
+
+static void samsung_timer_set_divisor(unsigned int channel, u8 divisor)
+{
+	u8 shift = TCFG1_SHIFT(channel);
+	unsigned long flags;
+	u32 reg;
+	u8 bits;
+
+	bits = (fls(divisor) - 1) - pwm.variant.div_base;
+
+	spin_lock_irqsave(&samsung_pwm_lock, flags);
+
+	reg = readl(pwm.base + REG_TCFG1);
+	reg &= ~(TCFG1_MUX_MASK << shift);
+	reg |= bits << shift;
+	writel(reg, pwm.base + REG_TCFG1);
+
+	spin_unlock_irqrestore(&samsung_pwm_lock, flags);
+}
+
+static void samsung_time_stop(unsigned int channel)
+{
+	unsigned long tcon;
+	unsigned long flags;
+
+	if (channel > 0)
+		++channel;
+
+	spin_lock_irqsave(&samsung_pwm_lock, flags);
+
+	tcon = readl_relaxed(pwm.base + REG_TCON);
+	tcon &= ~TCON_START(channel);
+	writel_relaxed(tcon, pwm.base + REG_TCON);
+
+	spin_unlock_irqrestore(&samsung_pwm_lock, flags);
+}
+
+static void samsung_time_setup(unsigned int channel, unsigned long tcnt)
+{
+	unsigned long tcon;
+	unsigned long flags;
+	unsigned int tcon_chan = channel;
+
+	if (tcon_chan > 0)
+		++tcon_chan;
+
+	spin_lock_irqsave(&samsung_pwm_lock, flags);
+
+	tcon = readl_relaxed(pwm.base + REG_TCON);
+
+	tcon &= ~(TCON_START(tcon_chan) | TCON_AUTORELOAD(tcon_chan));
+	tcon |= TCON_MANUALUPDATE(tcon_chan);
+
+	writel_relaxed(tcnt, pwm.base + REG_TCNTB(channel));
+	writel_relaxed(tcnt, pwm.base + REG_TCMPB(channel));
+	writel_relaxed(tcon, pwm.base + REG_TCON);
+
+	spin_unlock_irqrestore(&samsung_pwm_lock, flags);
+}
+
+static void samsung_time_start(unsigned int channel, bool periodic)
+{
+	unsigned long tcon;
+	unsigned long flags;
+
+	if (channel > 0)
+		++channel;
+
+	spin_lock_irqsave(&samsung_pwm_lock, flags);
+
+	tcon = readl_relaxed(pwm.base + REG_TCON);
+
+	tcon &= ~TCON_MANUALUPDATE(channel);
+	tcon |= TCON_START(channel);
+
+	if (periodic)
+		tcon |= TCON_AUTORELOAD(channel);
+	else
+		tcon &= ~TCON_AUTORELOAD(channel);
+
+	writel_relaxed(tcon, pwm.base + REG_TCON);
+
+	spin_unlock_irqrestore(&samsung_pwm_lock, flags);
+}
+
+static int samsung_set_next_event(unsigned long cycles,
+				struct clock_event_device *evt)
+{
+	/*
+	 * This check is needed to account for internal rounding
+	 * errors inside clockevents core, which might result in
+	 * passing cycles = 0, which in turn would not generate any
+	 * timer interrupt and hang the system.
+	 *
+	 * Another solution would be to set up the clockevent device
+	 * with min_delta = 2, but this would unnecessarily increase
+	 * the minimum sleep period.
+	 */
+	if (!cycles)
+		cycles = 1;
+
+	samsung_time_setup(pwm.event_id, cycles);
+	samsung_time_start(pwm.event_id, false);
+
+	return 0;
+}
+
+static int samsung_shutdown(struct clock_event_device *evt)
+{
+	samsung_time_stop(pwm.event_id);
+	return 0;
+}
+
+static int samsung_set_periodic(struct clock_event_device *evt)
+{
+	samsung_time_stop(pwm.event_id);
+	samsung_time_setup(pwm.event_id, pwm.clock_count_per_tick - 1);
+	samsung_time_start(pwm.event_id, true);
+	return 0;
+}
+
+static void samsung_clockevent_resume(struct clock_event_device *cev)
+{
+	samsung_timer_set_prescale(pwm.event_id, pwm.tscaler_div);
+	samsung_timer_set_divisor(pwm.event_id, pwm.tdiv);
+
+	if (pwm.variant.has_tint_cstat) {
+		u32 mask = (1 << pwm.event_id);
+		writel(mask | (mask << 5), pwm.base + REG_TINT_CSTAT);
+	}
+}
+
+static struct clock_event_device time_event_device = {
+	.name			= "samsung_event_timer",
+	.features		= CLOCK_EVT_FEAT_PERIODIC |
+				  CLOCK_EVT_FEAT_ONESHOT,
+	.rating			= 200,
+	.set_next_event		= samsung_set_next_event,
+	.set_state_shutdown	= samsung_shutdown,
+	.set_state_periodic	= samsung_set_periodic,
+	.set_state_oneshot	= samsung_shutdown,
+	.tick_resume		= samsung_shutdown,
+	.resume			= samsung_clockevent_resume,
+};
+
+static irqreturn_t samsung_clock_event_isr(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	if (pwm.variant.has_tint_cstat) {
+		u32 mask = (1 << pwm.event_id);
+		writel(mask | (mask << 5), pwm.base + REG_TINT_CSTAT);
+	}
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static struct irqaction samsung_clock_event_irq = {
+	.name		= "samsung_time_irq",
+	.flags		= IRQF_TIMER | IRQF_IRQPOLL,
+	.handler	= samsung_clock_event_isr,
+	.dev_id		= &time_event_device,
+};
+
+static void __init samsung_clockevent_init(void)
+{
+	unsigned long pclk;
+	unsigned long clock_rate;
+	unsigned int irq_number;
+
+	pclk = clk_get_rate(pwm.timerclk);
+
+	samsung_timer_set_prescale(pwm.event_id, pwm.tscaler_div);
+	samsung_timer_set_divisor(pwm.event_id, pwm.tdiv);
+
+	clock_rate = pclk / (pwm.tscaler_div * pwm.tdiv);
+	pwm.clock_count_per_tick = clock_rate / HZ;
+
+	time_event_device.cpumask = cpumask_of(0);
+	clockevents_config_and_register(&time_event_device,
+						clock_rate, 1, pwm.tcnt_max);
+
+	irq_number = pwm.irq[pwm.event_id];
+	setup_irq(irq_number, &samsung_clock_event_irq);
+
+	if (pwm.variant.has_tint_cstat) {
+		u32 mask = (1 << pwm.event_id);
+		writel(mask | (mask << 5), pwm.base + REG_TINT_CSTAT);
+	}
+}
+
+static void samsung_clocksource_suspend(struct clocksource *cs)
+{
+	samsung_time_stop(pwm.source_id);
+}
+
+static void samsung_clocksource_resume(struct clocksource *cs)
+{
+	samsung_timer_set_prescale(pwm.source_id, pwm.tscaler_div);
+	samsung_timer_set_divisor(pwm.source_id, pwm.tdiv);
+
+	samsung_time_setup(pwm.source_id, pwm.tcnt_max);
+	samsung_time_start(pwm.source_id, true);
+}
+
+static u64 notrace samsung_clocksource_read(struct clocksource *c)
+{
+	return ~readl_relaxed(pwm.source_reg);
+}
+
+static struct clocksource samsung_clocksource = {
+	.name		= "samsung_clocksource_timer",
+	.rating		= 250,
+	.read		= samsung_clocksource_read,
+	.suspend	= samsung_clocksource_suspend,
+	.resume		= samsung_clocksource_resume,
+	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+/*
+ * Override the global weak sched_clock symbol with this
+ * local implementation which uses the clocksource to get some
+ * better resolution when scheduling the kernel. We accept that
+ * this wraps around for now, since it is just a relative time
+ * stamp. (Inspired by U300 implementation.)
+ */
+static u64 notrace samsung_read_sched_clock(void)
+{
+	return samsung_clocksource_read(NULL);
+}
+
+static int __init samsung_clocksource_init(void)
+{
+	unsigned long pclk;
+	unsigned long clock_rate;
+
+	pclk = clk_get_rate(pwm.timerclk);
+
+	samsung_timer_set_prescale(pwm.source_id, pwm.tscaler_div);
+	samsung_timer_set_divisor(pwm.source_id, pwm.tdiv);
+
+	clock_rate = pclk / (pwm.tscaler_div * pwm.tdiv);
+
+	samsung_time_setup(pwm.source_id, pwm.tcnt_max);
+	samsung_time_start(pwm.source_id, true);
+
+	if (pwm.source_id == 4)
+		pwm.source_reg = pwm.base + 0x40;
+	else
+		pwm.source_reg = pwm.base + pwm.source_id * 0x0c + 0x14;
+
+	sched_clock_register(samsung_read_sched_clock,
+						pwm.variant.bits, clock_rate);
+
+	samsung_clocksource.mask = CLOCKSOURCE_MASK(pwm.variant.bits);
+	return clocksource_register_hz(&samsung_clocksource, clock_rate);
+}
+
+static void __init samsung_timer_resources(void)
+{
+	clk_prepare_enable(pwm.timerclk);
+
+	pwm.tcnt_max = (1UL << pwm.variant.bits) - 1;
+	if (pwm.variant.bits == 16) {
+		pwm.tscaler_div = 25;
+		pwm.tdiv = 2;
+	} else {
+		pwm.tscaler_div = 2;
+		pwm.tdiv = 1;
+	}
+}
+
+/*
+ * PWM master driver
+ */
+static int __init _samsung_pwm_clocksource_init(void)
+{
+	u8 mask;
+	int channel;
+
+	mask = ~pwm.variant.output_mask & ((1 << SAMSUNG_PWM_NUM) - 1);
+	channel = fls(mask) - 1;
+	if (channel < 0) {
+		pr_crit("failed to find PWM channel for clocksource\n");
+		return -EINVAL;
+	}
+	pwm.source_id = channel;
+
+	mask &= ~(1 << channel);
+	channel = fls(mask) - 1;
+	if (channel < 0) {
+		pr_crit("failed to find PWM channel for clock event\n");
+		return -EINVAL;
+	}
+	pwm.event_id = channel;
+
+	samsung_timer_resources();
+	samsung_clockevent_init();
+
+	return samsung_clocksource_init();
+}
+
+void __init samsung_pwm_clocksource_init(void __iomem *base,
+			unsigned int *irqs, struct samsung_pwm_variant *variant)
+{
+	pwm.base = base;
+	memcpy(&pwm.variant, variant, sizeof(pwm.variant));
+	memcpy(pwm.irq, irqs, SAMSUNG_PWM_NUM * sizeof(*irqs));
+
+	pwm.timerclk = clk_get(NULL, "timers");
+	if (IS_ERR(pwm.timerclk))
+		panic("failed to get timers clock for timer");
+
+	_samsung_pwm_clocksource_init();
+}
+
+#ifdef CONFIG_TIMER_OF
+static int __init samsung_pwm_alloc(struct device_node *np,
+				    const struct samsung_pwm_variant *variant)
+{
+	struct property *prop;
+	const __be32 *cur;
+	u32 val;
+	int i;
+
+	memcpy(&pwm.variant, variant, sizeof(pwm.variant));
+	for (i = 0; i < SAMSUNG_PWM_NUM; ++i)
+		pwm.irq[i] = irq_of_parse_and_map(np, i);
+
+	of_property_for_each_u32(np, "samsung,pwm-outputs", prop, cur, val) {
+		if (val >= SAMSUNG_PWM_NUM) {
+			pr_warning("%s: invalid channel index in samsung,pwm-outputs property\n",
+								__func__);
+			continue;
+		}
+		pwm.variant.output_mask |= 1 << val;
+	}
+
+	pwm.base = of_iomap(np, 0);
+	if (!pwm.base) {
+		pr_err("%s: failed to map PWM registers\n", __func__);
+		return -ENXIO;
+	}
+
+	pwm.timerclk = of_clk_get_by_name(np, "timers");
+	if (IS_ERR(pwm.timerclk)) {
+		pr_crit("failed to get timers clock for timer\n");
+		return PTR_ERR(pwm.timerclk);
+	}
+
+	return _samsung_pwm_clocksource_init();
+}
+
+static const struct samsung_pwm_variant s3c24xx_variant = {
+	.bits		= 16,
+	.div_base	= 1,
+	.has_tint_cstat	= false,
+	.tclk_mask	= (1 << 4),
+};
+
+static int __init s3c2410_pwm_clocksource_init(struct device_node *np)
+{
+	return samsung_pwm_alloc(np, &s3c24xx_variant);
+}
+TIMER_OF_DECLARE(s3c2410_pwm, "samsung,s3c2410-pwm", s3c2410_pwm_clocksource_init);
+
+static const struct samsung_pwm_variant s3c64xx_variant = {
+	.bits		= 32,
+	.div_base	= 0,
+	.has_tint_cstat	= true,
+	.tclk_mask	= (1 << 7) | (1 << 6) | (1 << 5),
+};
+
+static int __init s3c64xx_pwm_clocksource_init(struct device_node *np)
+{
+	return samsung_pwm_alloc(np, &s3c64xx_variant);
+}
+TIMER_OF_DECLARE(s3c6400_pwm, "samsung,s3c6400-pwm", s3c64xx_pwm_clocksource_init);
+
+static const struct samsung_pwm_variant s5p64x0_variant = {
+	.bits		= 32,
+	.div_base	= 0,
+	.has_tint_cstat	= true,
+	.tclk_mask	= 0,
+};
+
+static int __init s5p64x0_pwm_clocksource_init(struct device_node *np)
+{
+	return samsung_pwm_alloc(np, &s5p64x0_variant);
+}
+TIMER_OF_DECLARE(s5p6440_pwm, "samsung,s5p6440-pwm", s5p64x0_pwm_clocksource_init);
+
+static const struct samsung_pwm_variant s5p_variant = {
+	.bits		= 32,
+	.div_base	= 0,
+	.has_tint_cstat	= true,
+	.tclk_mask	= (1 << 5),
+};
+
+static int __init s5p_pwm_clocksource_init(struct device_node *np)
+{
+	return samsung_pwm_alloc(np, &s5p_variant);
+}
+TIMER_OF_DECLARE(s5pc100_pwm, "samsung,s5pc100-pwm", s5p_pwm_clocksource_init);
+#endif

drivers/clocksource/scx200_hrt.c

@@ -0,0 +1,93 @@
+/*
+ * Copyright (C) 2006 Jim Cromie
+ *
+ * This is a clocksource driver for the Geode SCx200's 1 or 27 MHz
+ * high-resolution timer.  The Geode SC-1100 (at least) has a buggy
+ * time stamp counter (TSC), which loses time unless 'idle=poll' is
+ * given as a boot-arg. In its absence, the Generic Timekeeping code
+ * will detect and de-rate the bad TSC, allowing this timer to take
+ * over timekeeping duties.
+ *
+ * Based on work by John Stultz, and Ted Phelps (in a 2.6.12-rc6 patch)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ */
+
+#include <linux/clocksource.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/ioport.h>
+#include <linux/scx200.h>
+
+#define NAME "scx200_hrt"
+
+static int mhz27;
+module_param(mhz27, int, 0);	/* load time only */
+MODULE_PARM_DESC(mhz27, "count at 27.0 MHz (default is 1.0 MHz)");
+
+static int ppm;
+module_param(ppm, int, 0);	/* load time only */
+MODULE_PARM_DESC(ppm, "+-adjust to actual XO freq (ppm)");
+
+/* HiRes Timer configuration register address */
+#define SCx200_TMCNFG_OFFSET (SCx200_TIMER_OFFSET + 5)
+
+/* and config settings */
+#define HR_TMEN (1 << 0)	/* timer interrupt enable */
+#define HR_TMCLKSEL (1 << 1)	/* 1|0 counts at 27|1 MHz */
+#define HR_TM27MPD (1 << 2)	/* 1 turns off input clock (power-down) */
+
+/* The base timer frequency, * 27 if selected */
+#define HRT_FREQ   1000000
+
+static u64 read_hrt(struct clocksource *cs)
+{
+	/* Read the timer value */
+	return (u64) inl(scx200_cb_base + SCx200_TIMER_OFFSET);
+}
+
+static struct clocksource cs_hrt = {
+	.name		= "scx200_hrt",
+	.rating		= 250,
+	.read		= read_hrt,
+	.mask		= CLOCKSOURCE_MASK(32),
+	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
+	/* mult, shift are set based on mhz27 flag */
+};
+
+static int __init init_hrt_clocksource(void)
+{
+	u32 freq;
+	/* Make sure scx200 has initialized the configuration block */
+	if (!scx200_cb_present())
+		return -ENODEV;
+
+	/* Reserve the timer's ISA io-region for ourselves */
+	if (!request_region(scx200_cb_base + SCx200_TIMER_OFFSET,
+			    SCx200_TIMER_SIZE,
+			    "NatSemi SCx200 High-Resolution Timer")) {
+		pr_warn("unable to lock timer region\n");
+		return -ENODEV;
+	}
+
+	/* write timer config */
+	outb(HR_TMEN | (mhz27 ? HR_TMCLKSEL : 0),
+	     scx200_cb_base + SCx200_TMCNFG_OFFSET);
+
+	freq = (HRT_FREQ + ppm);
+	if (mhz27)
+		freq *= 27;
+
+	pr_info("enabling scx200 high-res timer (%s MHz +%d ppm)\n", mhz27 ? "27":"1", ppm);
+
+	return clocksource_register_hz(&cs_hrt, freq);
+}
+
+module_init(init_hrt_clocksource);
+
+MODULE_AUTHOR("Jim Cromie <jim.cromie@gmail.com>");
+MODULE_DESCRIPTION("clocksource on SCx200 HiRes Timer");
+MODULE_LICENSE("GPL");

drivers/clocksource/sh_mtu2.c

@@ -0,0 +1,528 @@
+/*
+ * SuperH Timer Support - MTU2
+ *
+ *  Copyright (C) 2009 Magnus Damm
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_runtime.h>
+#include <linux/sh_timer.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+struct sh_mtu2_device;
+
+struct sh_mtu2_channel {
+	struct sh_mtu2_device *mtu;
+	unsigned int index;
+
+	void __iomem *base;
+
+	struct clock_event_device ced;
+};
+
+struct sh_mtu2_device {
+	struct platform_device *pdev;
+
+	void __iomem *mapbase;
+	struct clk *clk;
+
+	raw_spinlock_t lock; /* Protect the shared registers */
+
+	struct sh_mtu2_channel *channels;
+	unsigned int num_channels;
+
+	bool has_clockevent;
+};
+
+#define TSTR -1 /* shared register */
+#define TCR  0 /* channel register */
+#define TMDR 1 /* channel register */
+#define TIOR 2 /* channel register */
+#define TIER 3 /* channel register */
+#define TSR  4 /* channel register */
+#define TCNT 5 /* channel register */
+#define TGR  6 /* channel register */
+
+#define TCR_CCLR_NONE		(0 << 5)
+#define TCR_CCLR_TGRA		(1 << 5)
+#define TCR_CCLR_TGRB		(2 << 5)
+#define TCR_CCLR_SYNC		(3 << 5)
+#define TCR_CCLR_TGRC		(5 << 5)
+#define TCR_CCLR_TGRD		(6 << 5)
+#define TCR_CCLR_MASK		(7 << 5)
+#define TCR_CKEG_RISING		(0 << 3)
+#define TCR_CKEG_FALLING	(1 << 3)
+#define TCR_CKEG_BOTH		(2 << 3)
+#define TCR_CKEG_MASK		(3 << 3)
+/* Values 4 to 7 are channel-dependent */
+#define TCR_TPSC_P1		(0 << 0)
+#define TCR_TPSC_P4		(1 << 0)
+#define TCR_TPSC_P16		(2 << 0)
+#define TCR_TPSC_P64		(3 << 0)
+#define TCR_TPSC_CH0_TCLKA	(4 << 0)
+#define TCR_TPSC_CH0_TCLKB	(5 << 0)
+#define TCR_TPSC_CH0_TCLKC	(6 << 0)
+#define TCR_TPSC_CH0_TCLKD	(7 << 0)
+#define TCR_TPSC_CH1_TCLKA	(4 << 0)
+#define TCR_TPSC_CH1_TCLKB	(5 << 0)
+#define TCR_TPSC_CH1_P256	(6 << 0)
+#define TCR_TPSC_CH1_TCNT2	(7 << 0)
+#define TCR_TPSC_CH2_TCLKA	(4 << 0)
+#define TCR_TPSC_CH2_TCLKB	(5 << 0)
+#define TCR_TPSC_CH2_TCLKC	(6 << 0)
+#define TCR_TPSC_CH2_P1024	(7 << 0)
+#define TCR_TPSC_CH34_P256	(4 << 0)
+#define TCR_TPSC_CH34_P1024	(5 << 0)
+#define TCR_TPSC_CH34_TCLKA	(6 << 0)
+#define TCR_TPSC_CH34_TCLKB	(7 << 0)
+#define TCR_TPSC_MASK		(7 << 0)
+
+#define TMDR_BFE		(1 << 6)
+#define TMDR_BFB		(1 << 5)
+#define TMDR_BFA		(1 << 4)
+#define TMDR_MD_NORMAL		(0 << 0)
+#define TMDR_MD_PWM_1		(2 << 0)
+#define TMDR_MD_PWM_2		(3 << 0)
+#define TMDR_MD_PHASE_1		(4 << 0)
+#define TMDR_MD_PHASE_2		(5 << 0)
+#define TMDR_MD_PHASE_3		(6 << 0)
+#define TMDR_MD_PHASE_4		(7 << 0)
+#define TMDR_MD_PWM_SYNC	(8 << 0)
+#define TMDR_MD_PWM_COMP_CREST	(13 << 0)
+#define TMDR_MD_PWM_COMP_TROUGH	(14 << 0)
+#define TMDR_MD_PWM_COMP_BOTH	(15 << 0)
+#define TMDR_MD_MASK		(15 << 0)
+
+#define TIOC_IOCH(n)		((n) << 4)
+#define TIOC_IOCL(n)		((n) << 0)
+#define TIOR_OC_RETAIN		(0 << 0)
+#define TIOR_OC_0_CLEAR		(1 << 0)
+#define TIOR_OC_0_SET		(2 << 0)
+#define TIOR_OC_0_TOGGLE	(3 << 0)
+#define TIOR_OC_1_CLEAR		(5 << 0)
+#define TIOR_OC_1_SET		(6 << 0)
+#define TIOR_OC_1_TOGGLE	(7 << 0)
+#define TIOR_IC_RISING		(8 << 0)
+#define TIOR_IC_FALLING		(9 << 0)
+#define TIOR_IC_BOTH		(10 << 0)
+#define TIOR_IC_TCNT		(12 << 0)
+#define TIOR_MASK		(15 << 0)
+
+#define TIER_TTGE		(1 << 7)
+#define TIER_TTGE2		(1 << 6)
+#define TIER_TCIEU		(1 << 5)
+#define TIER_TCIEV		(1 << 4)
+#define TIER_TGIED		(1 << 3)
+#define TIER_TGIEC		(1 << 2)
+#define TIER_TGIEB		(1 << 1)
+#define TIER_TGIEA		(1 << 0)
+
+#define TSR_TCFD		(1 << 7)
+#define TSR_TCFU		(1 << 5)
+#define TSR_TCFV		(1 << 4)
+#define TSR_TGFD		(1 << 3)
+#define TSR_TGFC		(1 << 2)
+#define TSR_TGFB		(1 << 1)
+#define TSR_TGFA		(1 << 0)
+
+static unsigned long mtu2_reg_offs[] = {
+	[TCR] = 0,
+	[TMDR] = 1,
+	[TIOR] = 2,
+	[TIER] = 4,
+	[TSR] = 5,
+	[TCNT] = 6,
+	[TGR] = 8,
+};
+
+static inline unsigned long sh_mtu2_read(struct sh_mtu2_channel *ch, int reg_nr)
+{
+	unsigned long offs;
+
+	if (reg_nr == TSTR)
+		return ioread8(ch->mtu->mapbase + 0x280);
+
+	offs = mtu2_reg_offs[reg_nr];
+
+	if ((reg_nr == TCNT) || (reg_nr == TGR))
+		return ioread16(ch->base + offs);
+	else
+		return ioread8(ch->base + offs);
+}
+
+static inline void sh_mtu2_write(struct sh_mtu2_channel *ch, int reg_nr,
+				unsigned long value)
+{
+	unsigned long offs;
+
+	if (reg_nr == TSTR)
+		return iowrite8(value, ch->mtu->mapbase + 0x280);
+
+	offs = mtu2_reg_offs[reg_nr];
+
+	if ((reg_nr == TCNT) || (reg_nr == TGR))
+		iowrite16(value, ch->base + offs);
+	else
+		iowrite8(value, ch->base + offs);
+}
+
+static void sh_mtu2_start_stop_ch(struct sh_mtu2_channel *ch, int start)
+{
+	unsigned long flags, value;
+
+	/* start stop register shared by multiple timer channels */
+	raw_spin_lock_irqsave(&ch->mtu->lock, flags);
+	value = sh_mtu2_read(ch, TSTR);
+
+	if (start)
+		value |= 1 << ch->index;
+	else
+		value &= ~(1 << ch->index);
+
+	sh_mtu2_write(ch, TSTR, value);
+	raw_spin_unlock_irqrestore(&ch->mtu->lock, flags);
+}
+
+static int sh_mtu2_enable(struct sh_mtu2_channel *ch)
+{
+	unsigned long periodic;
+	unsigned long rate;
+	int ret;
+
+	pm_runtime_get_sync(&ch->mtu->pdev->dev);
+	dev_pm_syscore_device(&ch->mtu->pdev->dev, true);
+
+	/* enable clock */
+	ret = clk_enable(ch->mtu->clk);
+	if (ret) {
+		dev_err(&ch->mtu->pdev->dev, "ch%u: cannot enable clock\n",
+			ch->index);
+		return ret;
+	}
+
+	/* make sure channel is disabled */
+	sh_mtu2_start_stop_ch(ch, 0);
+
+	rate = clk_get_rate(ch->mtu->clk) / 64;
+	periodic = (rate + HZ/2) / HZ;
+
+	/*
+	 * "Periodic Counter Operation"
+	 * Clear on TGRA compare match, divide clock by 64.
+	 */
+	sh_mtu2_write(ch, TCR, TCR_CCLR_TGRA | TCR_TPSC_P64);
+	sh_mtu2_write(ch, TIOR, TIOC_IOCH(TIOR_OC_0_CLEAR) |
+		      TIOC_IOCL(TIOR_OC_0_CLEAR));
+	sh_mtu2_write(ch, TGR, periodic);
+	sh_mtu2_write(ch, TCNT, 0);
+	sh_mtu2_write(ch, TMDR, TMDR_MD_NORMAL);
+	sh_mtu2_write(ch, TIER, TIER_TGIEA);
+
+	/* enable channel */
+	sh_mtu2_start_stop_ch(ch, 1);
+
+	return 0;
+}
+
+static void sh_mtu2_disable(struct sh_mtu2_channel *ch)
+{
+	/* disable channel */
+	sh_mtu2_start_stop_ch(ch, 0);
+
+	/* stop clock */
+	clk_disable(ch->mtu->clk);
+
+	dev_pm_syscore_device(&ch->mtu->pdev->dev, false);
+	pm_runtime_put(&ch->mtu->pdev->dev);
+}
+
+static irqreturn_t sh_mtu2_interrupt(int irq, void *dev_id)
+{
+	struct sh_mtu2_channel *ch = dev_id;
+
+	/* acknowledge interrupt */
+	sh_mtu2_read(ch, TSR);
+	sh_mtu2_write(ch, TSR, ~TSR_TGFA);
+
+	/* notify clockevent layer */
+	ch->ced.event_handler(&ch->ced);
+	return IRQ_HANDLED;
+}
+
+static struct sh_mtu2_channel *ced_to_sh_mtu2(struct clock_event_device *ced)
+{
+	return container_of(ced, struct sh_mtu2_channel, ced);
+}
+
+static int sh_mtu2_clock_event_shutdown(struct clock_event_device *ced)
+{
+	struct sh_mtu2_channel *ch = ced_to_sh_mtu2(ced);
+
+	if (clockevent_state_periodic(ced))
+		sh_mtu2_disable(ch);
+
+	return 0;
+}
+
+static int sh_mtu2_clock_event_set_periodic(struct clock_event_device *ced)
+{
+	struct sh_mtu2_channel *ch = ced_to_sh_mtu2(ced);
+
+	if (clockevent_state_periodic(ced))
+		sh_mtu2_disable(ch);
+
+	dev_info(&ch->mtu->pdev->dev, "ch%u: used for periodic clock events\n",
+		 ch->index);
+	sh_mtu2_enable(ch);
+	return 0;
+}
+
+static void sh_mtu2_clock_event_suspend(struct clock_event_device *ced)
+{
+	pm_genpd_syscore_poweroff(&ced_to_sh_mtu2(ced)->mtu->pdev->dev);
+}
+
+static void sh_mtu2_clock_event_resume(struct clock_event_device *ced)
+{
+	pm_genpd_syscore_poweron(&ced_to_sh_mtu2(ced)->mtu->pdev->dev);
+}
+
+static void sh_mtu2_register_clockevent(struct sh_mtu2_channel *ch,
+					const char *name)
+{
+	struct clock_event_device *ced = &ch->ced;
+
+	ced->name = name;
+	ced->features = CLOCK_EVT_FEAT_PERIODIC;
+	ced->rating = 200;
+	ced->cpumask = cpu_possible_mask;
+	ced->set_state_shutdown = sh_mtu2_clock_event_shutdown;
+	ced->set_state_periodic = sh_mtu2_clock_event_set_periodic;
+	ced->suspend = sh_mtu2_clock_event_suspend;
+	ced->resume = sh_mtu2_clock_event_resume;
+
+	dev_info(&ch->mtu->pdev->dev, "ch%u: used for clock events\n",
+		 ch->index);
+	clockevents_register_device(ced);
+}
+
+static int sh_mtu2_register(struct sh_mtu2_channel *ch, const char *name)
+{
+	ch->mtu->has_clockevent = true;
+	sh_mtu2_register_clockevent(ch, name);
+
+	return 0;
+}
+
+static int sh_mtu2_setup_channel(struct sh_mtu2_channel *ch, unsigned int index,
+				 struct sh_mtu2_device *mtu)
+{
+	static const unsigned int channel_offsets[] = {
+		0x300, 0x380, 0x000,
+	};
+	char name[6];
+	int irq;
+	int ret;
+
+	ch->mtu = mtu;
+
+	sprintf(name, "tgi%ua", index);
+	irq = platform_get_irq_byname(mtu->pdev, name);
+	if (irq < 0) {
+		/* Skip channels with no declared interrupt. */
+		return 0;
+	}
+
+	ret = request_irq(irq, sh_mtu2_interrupt,
+			  IRQF_TIMER | IRQF_IRQPOLL | IRQF_NOBALANCING,
+			  dev_name(&ch->mtu->pdev->dev), ch);
+	if (ret) {
+		dev_err(&ch->mtu->pdev->dev, "ch%u: failed to request irq %d\n",
+			index, irq);
+		return ret;
+	}
+
+	ch->base = mtu->mapbase + channel_offsets[index];
+	ch->index = index;
+
+	return sh_mtu2_register(ch, dev_name(&mtu->pdev->dev));
+}
+
+static int sh_mtu2_map_memory(struct sh_mtu2_device *mtu)
+{
+	struct resource *res;
+
+	res = platform_get_resource(mtu->pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&mtu->pdev->dev, "failed to get I/O memory\n");
+		return -ENXIO;
+	}
+
+	mtu->mapbase = ioremap_nocache(res->start, resource_size(res));
+	if (mtu->mapbase == NULL)
+		return -ENXIO;
+
+	return 0;
+}
+
+static int sh_mtu2_setup(struct sh_mtu2_device *mtu,
+			 struct platform_device *pdev)
+{
+	unsigned int i;
+	int ret;
+
+	mtu->pdev = pdev;
+
+	raw_spin_lock_init(&mtu->lock);
+
+	/* Get hold of clock. */
+	mtu->clk = clk_get(&mtu->pdev->dev, "fck");
+	if (IS_ERR(mtu->clk)) {
+		dev_err(&mtu->pdev->dev, "cannot get clock\n");
+		return PTR_ERR(mtu->clk);
+	}
+
+	ret = clk_prepare(mtu->clk);
+	if (ret < 0)
+		goto err_clk_put;
+
+	/* Map the memory resource. */
+	ret = sh_mtu2_map_memory(mtu);
+	if (ret < 0) {
+		dev_err(&mtu->pdev->dev, "failed to remap I/O memory\n");
+		goto err_clk_unprepare;
+	}
+
+	/* Allocate and setup the channels. */
+	mtu->num_channels = 3;
+
+	mtu->channels = kcalloc(mtu->num_channels, sizeof(*mtu->channels),
+				GFP_KERNEL);
+	if (mtu->channels == NULL) {
+		ret = -ENOMEM;
+		goto err_unmap;
+	}
+
+	for (i = 0; i < mtu->num_channels; ++i) {
+		ret = sh_mtu2_setup_channel(&mtu->channels[i], i, mtu);
+		if (ret < 0)
+			goto err_unmap;
+	}
+
+	platform_set_drvdata(pdev, mtu);
+
+	return 0;
+
+err_unmap:
+	kfree(mtu->channels);
+	iounmap(mtu->mapbase);
+err_clk_unprepare:
+	clk_unprepare(mtu->clk);
+err_clk_put:
+	clk_put(mtu->clk);
+	return ret;
+}
+
+static int sh_mtu2_probe(struct platform_device *pdev)
+{
+	struct sh_mtu2_device *mtu = platform_get_drvdata(pdev);
+	int ret;
+
+	if (!is_early_platform_device(pdev)) {
+		pm_runtime_set_active(&pdev->dev);
+		pm_runtime_enable(&pdev->dev);
+	}
+
+	if (mtu) {
+		dev_info(&pdev->dev, "kept as earlytimer\n");
+		goto out;
+	}
+
+	mtu = kzalloc(sizeof(*mtu), GFP_KERNEL);
+	if (mtu == NULL)
+		return -ENOMEM;
+
+	ret = sh_mtu2_setup(mtu, pdev);
+	if (ret) {
+		kfree(mtu);
+		pm_runtime_idle(&pdev->dev);
+		return ret;
+	}
+	if (is_early_platform_device(pdev))
+		return 0;
+
+ out:
+	if (mtu->has_clockevent)
+		pm_runtime_irq_safe(&pdev->dev);
+	else
+		pm_runtime_idle(&pdev->dev);
+
+	return 0;
+}
+
+static int sh_mtu2_remove(struct platform_device *pdev)
+{
+	return -EBUSY; /* cannot unregister clockevent */
+}
+
+static const struct platform_device_id sh_mtu2_id_table[] = {
+	{ "sh-mtu2", 0 },
+	{ },
+};
+MODULE_DEVICE_TABLE(platform, sh_mtu2_id_table);
+
+static const struct of_device_id sh_mtu2_of_table[] __maybe_unused = {
+	{ .compatible = "renesas,mtu2" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, sh_mtu2_of_table);
+
+static struct platform_driver sh_mtu2_device_driver = {
+	.probe		= sh_mtu2_probe,
+	.remove		= sh_mtu2_remove,
+	.driver		= {
+		.name	= "sh_mtu2",
+		.of_match_table = of_match_ptr(sh_mtu2_of_table),
+	},
+	.id_table	= sh_mtu2_id_table,
+};
+
+static int __init sh_mtu2_init(void)
+{
+	return platform_driver_register(&sh_mtu2_device_driver);
+}
+
+static void __exit sh_mtu2_exit(void)
+{
+	platform_driver_unregister(&sh_mtu2_device_driver);
+}
+
+early_platform_init("earlytimer", &sh_mtu2_device_driver);
+subsys_initcall(sh_mtu2_init);
+module_exit(sh_mtu2_exit);
+
+MODULE_AUTHOR("Magnus Damm");
+MODULE_DESCRIPTION("SuperH MTU2 Timer Driver");
+MODULE_LICENSE("GPL v2");

drivers/clocksource/sh_tmu.c

@@ -0,0 +1,685 @@
+/*
+ * SuperH Timer Support - TMU
+ *
+ *  Copyright (C) 2009 Magnus Damm
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pm_domain.h>
+#include <linux/pm_runtime.h>
+#include <linux/sh_timer.h>
+#include <linux/slab.h>
+#include <linux/spinlock.h>
+
+enum sh_tmu_model {
+	SH_TMU,
+	SH_TMU_SH3,
+};
+
+struct sh_tmu_device;
+
+struct sh_tmu_channel {
+	struct sh_tmu_device *tmu;
+	unsigned int index;
+
+	void __iomem *base;
+	int irq;
+
+	unsigned long periodic;
+	struct clock_event_device ced;
+	struct clocksource cs;
+	bool cs_enabled;
+	unsigned int enable_count;
+};
+
+struct sh_tmu_device {
+	struct platform_device *pdev;
+
+	void __iomem *mapbase;
+	struct clk *clk;
+	unsigned long rate;
+
+	enum sh_tmu_model model;
+
+	raw_spinlock_t lock; /* Protect the shared start/stop register */
+
+	struct sh_tmu_channel *channels;
+	unsigned int num_channels;
+
+	bool has_clockevent;
+	bool has_clocksource;
+};
+
+#define TSTR -1 /* shared register */
+#define TCOR  0 /* channel register */
+#define TCNT 1 /* channel register */
+#define TCR 2 /* channel register */
+
+#define TCR_UNF			(1 << 8)
+#define TCR_UNIE		(1 << 5)
+#define TCR_TPSC_CLK4		(0 << 0)
+#define TCR_TPSC_CLK16		(1 << 0)
+#define TCR_TPSC_CLK64		(2 << 0)
+#define TCR_TPSC_CLK256		(3 << 0)
+#define TCR_TPSC_CLK1024	(4 << 0)
+#define TCR_TPSC_MASK		(7 << 0)
+
+static inline unsigned long sh_tmu_read(struct sh_tmu_channel *ch, int reg_nr)
+{
+	unsigned long offs;
+
+	if (reg_nr == TSTR) {
+		switch (ch->tmu->model) {
+		case SH_TMU_SH3:
+			return ioread8(ch->tmu->mapbase + 2);
+		case SH_TMU:
+			return ioread8(ch->tmu->mapbase + 4);
+		}
+	}
+
+	offs = reg_nr << 2;
+
+	if (reg_nr == TCR)
+		return ioread16(ch->base + offs);
+	else
+		return ioread32(ch->base + offs);
+}
+
+static inline void sh_tmu_write(struct sh_tmu_channel *ch, int reg_nr,
+				unsigned long value)
+{
+	unsigned long offs;
+
+	if (reg_nr == TSTR) {
+		switch (ch->tmu->model) {
+		case SH_TMU_SH3:
+			return iowrite8(value, ch->tmu->mapbase + 2);
+		case SH_TMU:
+			return iowrite8(value, ch->tmu->mapbase + 4);
+		}
+	}
+
+	offs = reg_nr << 2;
+
+	if (reg_nr == TCR)
+		iowrite16(value, ch->base + offs);
+	else
+		iowrite32(value, ch->base + offs);
+}
+
+static void sh_tmu_start_stop_ch(struct sh_tmu_channel *ch, int start)
+{
+	unsigned long flags, value;
+
+	/* start stop register shared by multiple timer channels */
+	raw_spin_lock_irqsave(&ch->tmu->lock, flags);
+	value = sh_tmu_read(ch, TSTR);
+
+	if (start)
+		value |= 1 << ch->index;
+	else
+		value &= ~(1 << ch->index);
+
+	sh_tmu_write(ch, TSTR, value);
+	raw_spin_unlock_irqrestore(&ch->tmu->lock, flags);
+}
+
+static int __sh_tmu_enable(struct sh_tmu_channel *ch)
+{
+	int ret;
+
+	/* enable clock */
+	ret = clk_enable(ch->tmu->clk);
+	if (ret) {
+		dev_err(&ch->tmu->pdev->dev, "ch%u: cannot enable clock\n",
+			ch->index);
+		return ret;
+	}
+
+	/* make sure channel is disabled */
+	sh_tmu_start_stop_ch(ch, 0);
+
+	/* maximum timeout */
+	sh_tmu_write(ch, TCOR, 0xffffffff);
+	sh_tmu_write(ch, TCNT, 0xffffffff);
+
+	/* configure channel to parent clock / 4, irq off */
+	sh_tmu_write(ch, TCR, TCR_TPSC_CLK4);
+
+	/* enable channel */
+	sh_tmu_start_stop_ch(ch, 1);
+
+	return 0;
+}
+
+static int sh_tmu_enable(struct sh_tmu_channel *ch)
+{
+	if (ch->enable_count++ > 0)
+		return 0;
+
+	pm_runtime_get_sync(&ch->tmu->pdev->dev);
+	dev_pm_syscore_device(&ch->tmu->pdev->dev, true);
+
+	return __sh_tmu_enable(ch);
+}
+
+static void __sh_tmu_disable(struct sh_tmu_channel *ch)
+{
+	/* disable channel */
+	sh_tmu_start_stop_ch(ch, 0);
+
+	/* disable interrupts in TMU block */
+	sh_tmu_write(ch, TCR, TCR_TPSC_CLK4);
+
+	/* stop clock */
+	clk_disable(ch->tmu->clk);
+}
+
+static void sh_tmu_disable(struct sh_tmu_channel *ch)
+{
+	if (WARN_ON(ch->enable_count == 0))
+		return;
+
+	if (--ch->enable_count > 0)
+		return;
+
+	__sh_tmu_disable(ch);
+
+	dev_pm_syscore_device(&ch->tmu->pdev->dev, false);
+	pm_runtime_put(&ch->tmu->pdev->dev);
+}
+
+static void sh_tmu_set_next(struct sh_tmu_channel *ch, unsigned long delta,
+			    int periodic)
+{
+	/* stop timer */
+	sh_tmu_start_stop_ch(ch, 0);
+
+	/* acknowledge interrupt */
+	sh_tmu_read(ch, TCR);
+
+	/* enable interrupt */
+	sh_tmu_write(ch, TCR, TCR_UNIE | TCR_TPSC_CLK4);
+
+	/* reload delta value in case of periodic timer */
+	if (periodic)
+		sh_tmu_write(ch, TCOR, delta);
+	else
+		sh_tmu_write(ch, TCOR, 0xffffffff);
+
+	sh_tmu_write(ch, TCNT, delta);
+
+	/* start timer */
+	sh_tmu_start_stop_ch(ch, 1);
+}
+
+static irqreturn_t sh_tmu_interrupt(int irq, void *dev_id)
+{
+	struct sh_tmu_channel *ch = dev_id;
+
+	/* disable or acknowledge interrupt */
+	if (clockevent_state_oneshot(&ch->ced))
+		sh_tmu_write(ch, TCR, TCR_TPSC_CLK4);
+	else
+		sh_tmu_write(ch, TCR, TCR_UNIE | TCR_TPSC_CLK4);
+
+	/* notify clockevent layer */
+	ch->ced.event_handler(&ch->ced);
+	return IRQ_HANDLED;
+}
+
+static struct sh_tmu_channel *cs_to_sh_tmu(struct clocksource *cs)
+{
+	return container_of(cs, struct sh_tmu_channel, cs);
+}
+
+static u64 sh_tmu_clocksource_read(struct clocksource *cs)
+{
+	struct sh_tmu_channel *ch = cs_to_sh_tmu(cs);
+
+	return sh_tmu_read(ch, TCNT) ^ 0xffffffff;
+}
+
+static int sh_tmu_clocksource_enable(struct clocksource *cs)
+{
+	struct sh_tmu_channel *ch = cs_to_sh_tmu(cs);
+	int ret;
+
+	if (WARN_ON(ch->cs_enabled))
+		return 0;
+
+	ret = sh_tmu_enable(ch);
+	if (!ret)
+		ch->cs_enabled = true;
+
+	return ret;
+}
+
+static void sh_tmu_clocksource_disable(struct clocksource *cs)
+{
+	struct sh_tmu_channel *ch = cs_to_sh_tmu(cs);
+
+	if (WARN_ON(!ch->cs_enabled))
+		return;
+
+	sh_tmu_disable(ch);
+	ch->cs_enabled = false;
+}
+
+static void sh_tmu_clocksource_suspend(struct clocksource *cs)
+{
+	struct sh_tmu_channel *ch = cs_to_sh_tmu(cs);
+
+	if (!ch->cs_enabled)
+		return;
+
+	if (--ch->enable_count == 0) {
+		__sh_tmu_disable(ch);
+		pm_genpd_syscore_poweroff(&ch->tmu->pdev->dev);
+	}
+}
+
+static void sh_tmu_clocksource_resume(struct clocksource *cs)
+{
+	struct sh_tmu_channel *ch = cs_to_sh_tmu(cs);
+
+	if (!ch->cs_enabled)
+		return;
+
+	if (ch->enable_count++ == 0) {
+		pm_genpd_syscore_poweron(&ch->tmu->pdev->dev);
+		__sh_tmu_enable(ch);
+	}
+}
+
+static int sh_tmu_register_clocksource(struct sh_tmu_channel *ch,
+				       const char *name)
+{
+	struct clocksource *cs = &ch->cs;
+
+	cs->name = name;
+	cs->rating = 200;
+	cs->read = sh_tmu_clocksource_read;
+	cs->enable = sh_tmu_clocksource_enable;
+	cs->disable = sh_tmu_clocksource_disable;
+	cs->suspend = sh_tmu_clocksource_suspend;
+	cs->resume = sh_tmu_clocksource_resume;
+	cs->mask = CLOCKSOURCE_MASK(32);
+	cs->flags = CLOCK_SOURCE_IS_CONTINUOUS;
+
+	dev_info(&ch->tmu->pdev->dev, "ch%u: used as clock source\n",
+		 ch->index);
+
+	clocksource_register_hz(cs, ch->tmu->rate);
+	return 0;
+}
+
+static struct sh_tmu_channel *ced_to_sh_tmu(struct clock_event_device *ced)
+{
+	return container_of(ced, struct sh_tmu_channel, ced);
+}
+
+static void sh_tmu_clock_event_start(struct sh_tmu_channel *ch, int periodic)
+{
+	sh_tmu_enable(ch);
+
+	if (periodic) {
+		ch->periodic = (ch->tmu->rate + HZ/2) / HZ;
+		sh_tmu_set_next(ch, ch->periodic, 1);
+	}
+}
+
+static int sh_tmu_clock_event_shutdown(struct clock_event_device *ced)
+{
+	struct sh_tmu_channel *ch = ced_to_sh_tmu(ced);
+
+	if (clockevent_state_oneshot(ced) || clockevent_state_periodic(ced))
+		sh_tmu_disable(ch);
+	return 0;
+}
+
+static int sh_tmu_clock_event_set_state(struct clock_event_device *ced,
+					int periodic)
+{
+	struct sh_tmu_channel *ch = ced_to_sh_tmu(ced);
+
+	/* deal with old setting first */
+	if (clockevent_state_oneshot(ced) || clockevent_state_periodic(ced))
+		sh_tmu_disable(ch);
+
+	dev_info(&ch->tmu->pdev->dev, "ch%u: used for %s clock events\n",
+		 ch->index, periodic ? "periodic" : "oneshot");
+	sh_tmu_clock_event_start(ch, periodic);
+	return 0;
+}
+
+static int sh_tmu_clock_event_set_oneshot(struct clock_event_device *ced)
+{
+	return sh_tmu_clock_event_set_state(ced, 0);
+}
+
+static int sh_tmu_clock_event_set_periodic(struct clock_event_device *ced)
+{
+	return sh_tmu_clock_event_set_state(ced, 1);
+}
+
+static int sh_tmu_clock_event_next(unsigned long delta,
+				   struct clock_event_device *ced)
+{
+	struct sh_tmu_channel *ch = ced_to_sh_tmu(ced);
+
+	BUG_ON(!clockevent_state_oneshot(ced));
+
+	/* program new delta value */
+	sh_tmu_set_next(ch, delta, 0);
+	return 0;
+}
+
+static void sh_tmu_clock_event_suspend(struct clock_event_device *ced)
+{
+	pm_genpd_syscore_poweroff(&ced_to_sh_tmu(ced)->tmu->pdev->dev);
+}
+
+static void sh_tmu_clock_event_resume(struct clock_event_device *ced)
+{
+	pm_genpd_syscore_poweron(&ced_to_sh_tmu(ced)->tmu->pdev->dev);
+}
+
+static void sh_tmu_register_clockevent(struct sh_tmu_channel *ch,
+				       const char *name)
+{
+	struct clock_event_device *ced = &ch->ced;
+	int ret;
+
+	ced->name = name;
+	ced->features = CLOCK_EVT_FEAT_PERIODIC;
+	ced->features |= CLOCK_EVT_FEAT_ONESHOT;
+	ced->rating = 200;
+	ced->cpumask = cpu_possible_mask;
+	ced->set_next_event = sh_tmu_clock_event_next;
+	ced->set_state_shutdown = sh_tmu_clock_event_shutdown;
+	ced->set_state_periodic = sh_tmu_clock_event_set_periodic;
+	ced->set_state_oneshot = sh_tmu_clock_event_set_oneshot;
+	ced->suspend = sh_tmu_clock_event_suspend;
+	ced->resume = sh_tmu_clock_event_resume;
+
+	dev_info(&ch->tmu->pdev->dev, "ch%u: used for clock events\n",
+		 ch->index);
+
+	clockevents_config_and_register(ced, ch->tmu->rate, 0x300, 0xffffffff);
+
+	ret = request_irq(ch->irq, sh_tmu_interrupt,
+			  IRQF_TIMER | IRQF_IRQPOLL | IRQF_NOBALANCING,
+			  dev_name(&ch->tmu->pdev->dev), ch);
+	if (ret) {
+		dev_err(&ch->tmu->pdev->dev, "ch%u: failed to request irq %d\n",
+			ch->index, ch->irq);
+		return;
+	}
+}
+
+static int sh_tmu_register(struct sh_tmu_channel *ch, const char *name,
+			   bool clockevent, bool clocksource)
+{
+	if (clockevent) {
+		ch->tmu->has_clockevent = true;
+		sh_tmu_register_clockevent(ch, name);
+	} else if (clocksource) {
+		ch->tmu->has_clocksource = true;
+		sh_tmu_register_clocksource(ch, name);
+	}
+
+	return 0;
+}
+
+static int sh_tmu_channel_setup(struct sh_tmu_channel *ch, unsigned int index,
+				bool clockevent, bool clocksource,
+				struct sh_tmu_device *tmu)
+{
+	/* Skip unused channels. */
+	if (!clockevent && !clocksource)
+		return 0;
+
+	ch->tmu = tmu;
+	ch->index = index;
+
+	if (tmu->model == SH_TMU_SH3)
+		ch->base = tmu->mapbase + 4 + ch->index * 12;
+	else
+		ch->base = tmu->mapbase + 8 + ch->index * 12;
+
+	ch->irq = platform_get_irq(tmu->pdev, index);
+	if (ch->irq < 0) {
+		dev_err(&tmu->pdev->dev, "ch%u: failed to get irq\n",
+			ch->index);
+		return ch->irq;
+	}
+
+	ch->cs_enabled = false;
+	ch->enable_count = 0;
+
+	return sh_tmu_register(ch, dev_name(&tmu->pdev->dev),
+			       clockevent, clocksource);
+}
+
+static int sh_tmu_map_memory(struct sh_tmu_device *tmu)
+{
+	struct resource *res;
+
+	res = platform_get_resource(tmu->pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&tmu->pdev->dev, "failed to get I/O memory\n");
+		return -ENXIO;
+	}
+
+	tmu->mapbase = ioremap_nocache(res->start, resource_size(res));
+	if (tmu->mapbase == NULL)
+		return -ENXIO;
+
+	return 0;
+}
+
+static int sh_tmu_parse_dt(struct sh_tmu_device *tmu)
+{
+	struct device_node *np = tmu->pdev->dev.of_node;
+
+	tmu->model = SH_TMU;
+	tmu->num_channels = 3;
+
+	of_property_read_u32(np, "#renesas,channels", &tmu->num_channels);
+
+	if (tmu->num_channels != 2 && tmu->num_channels != 3) {
+		dev_err(&tmu->pdev->dev, "invalid number of channels %u\n",
+			tmu->num_channels);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static int sh_tmu_setup(struct sh_tmu_device *tmu, struct platform_device *pdev)
+{
+	unsigned int i;
+	int ret;
+
+	tmu->pdev = pdev;
+
+	raw_spin_lock_init(&tmu->lock);
+
+	if (IS_ENABLED(CONFIG_OF) && pdev->dev.of_node) {
+		ret = sh_tmu_parse_dt(tmu);
+		if (ret < 0)
+			return ret;
+	} else if (pdev->dev.platform_data) {
+		const struct platform_device_id *id = pdev->id_entry;
+		struct sh_timer_config *cfg = pdev->dev.platform_data;
+
+		tmu->model = id->driver_data;
+		tmu->num_channels = hweight8(cfg->channels_mask);
+	} else {
+		dev_err(&tmu->pdev->dev, "missing platform data\n");
+		return -ENXIO;
+	}
+
+	/* Get hold of clock. */
+	tmu->clk = clk_get(&tmu->pdev->dev, "fck");
+	if (IS_ERR(tmu->clk)) {
+		dev_err(&tmu->pdev->dev, "cannot get clock\n");
+		return PTR_ERR(tmu->clk);
+	}
+
+	ret = clk_prepare(tmu->clk);
+	if (ret < 0)
+		goto err_clk_put;
+
+	/* Determine clock rate. */
+	ret = clk_enable(tmu->clk);
+	if (ret < 0)
+		goto err_clk_unprepare;
+
+	tmu->rate = clk_get_rate(tmu->clk) / 4;
+	clk_disable(tmu->clk);
+
+	/* Map the memory resource. */
+	ret = sh_tmu_map_memory(tmu);
+	if (ret < 0) {
+		dev_err(&tmu->pdev->dev, "failed to remap I/O memory\n");
+		goto err_clk_unprepare;
+	}
+
+	/* Allocate and setup the channels. */
+	tmu->channels = kcalloc(tmu->num_channels, sizeof(*tmu->channels),
+				GFP_KERNEL);
+	if (tmu->channels == NULL) {
+		ret = -ENOMEM;
+		goto err_unmap;
+	}
+
+	/*
+	 * Use the first channel as a clock event device and the second channel
+	 * as a clock source.
+	 */
+	for (i = 0; i < tmu->num_channels; ++i) {
+		ret = sh_tmu_channel_setup(&tmu->channels[i], i,
+					   i == 0, i == 1, tmu);
+		if (ret < 0)
+			goto err_unmap;
+	}
+
+	platform_set_drvdata(pdev, tmu);
+
+	return 0;
+
+err_unmap:
+	kfree(tmu->channels);
+	iounmap(tmu->mapbase);
+err_clk_unprepare:
+	clk_unprepare(tmu->clk);
+err_clk_put:
+	clk_put(tmu->clk);
+	return ret;
+}
+
+static int sh_tmu_probe(struct platform_device *pdev)
+{
+	struct sh_tmu_device *tmu = platform_get_drvdata(pdev);
+	int ret;
+
+	if (!is_early_platform_device(pdev)) {
+		pm_runtime_set_active(&pdev->dev);
+		pm_runtime_enable(&pdev->dev);
+	}
+
+	if (tmu) {
+		dev_info(&pdev->dev, "kept as earlytimer\n");
+		goto out;
+	}
+
+	tmu = kzalloc(sizeof(*tmu), GFP_KERNEL);
+	if (tmu == NULL)
+		return -ENOMEM;
+
+	ret = sh_tmu_setup(tmu, pdev);
+	if (ret) {
+		kfree(tmu);
+		pm_runtime_idle(&pdev->dev);
+		return ret;
+	}
+	if (is_early_platform_device(pdev))
+		return 0;
+
+ out:
+	if (tmu->has_clockevent || tmu->has_clocksource)
+		pm_runtime_irq_safe(&pdev->dev);
+	else
+		pm_runtime_idle(&pdev->dev);
+
+	return 0;
+}
+
+static int sh_tmu_remove(struct platform_device *pdev)
+{
+	return -EBUSY; /* cannot unregister clockevent and clocksource */
+}
+
+static const struct platform_device_id sh_tmu_id_table[] = {
+	{ "sh-tmu", SH_TMU },
+	{ "sh-tmu-sh3", SH_TMU_SH3 },
+	{ }
+};
+MODULE_DEVICE_TABLE(platform, sh_tmu_id_table);
+
+static const struct of_device_id sh_tmu_of_table[] __maybe_unused = {
+	{ .compatible = "renesas,tmu" },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, sh_tmu_of_table);
+
+static struct platform_driver sh_tmu_device_driver = {
+	.probe		= sh_tmu_probe,
+	.remove		= sh_tmu_remove,
+	.driver		= {
+		.name	= "sh_tmu",
+		.of_match_table = of_match_ptr(sh_tmu_of_table),
+	},
+	.id_table	= sh_tmu_id_table,
+};
+
+static int __init sh_tmu_init(void)
+{
+	return platform_driver_register(&sh_tmu_device_driver);
+}
+
+static void __exit sh_tmu_exit(void)
+{
+	platform_driver_unregister(&sh_tmu_device_driver);
+}
+
+early_platform_init("earlytimer", &sh_tmu_device_driver);
+subsys_initcall(sh_tmu_init);
+module_exit(sh_tmu_exit);
+
+MODULE_AUTHOR("Magnus Damm");
+MODULE_DESCRIPTION("SuperH TMU Timer Driver");
+MODULE_LICENSE("GPL v2");

drivers/clocksource/sun4i_timer.c

@@ -0,0 +1,220 @@
+/*
+ * Allwinner A1X SoCs timer handling.
+ *
+ * Copyright (C) 2012 Maxime Ripard
+ *
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * Based on code from
+ * Allwinner Technology Co., Ltd. <www.allwinnertech.com>
+ * Benn Huang <benn@allwinnertech.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqreturn.h>
+#include <linux/sched_clock.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#include "timer-of.h"
+
+#define TIMER_IRQ_EN_REG	0x00
+#define TIMER_IRQ_EN(val)		BIT(val)
+#define TIMER_IRQ_ST_REG	0x04
+#define TIMER_CTL_REG(val)	(0x10 * val + 0x10)
+#define TIMER_CTL_ENABLE		BIT(0)
+#define TIMER_CTL_RELOAD		BIT(1)
+#define TIMER_CTL_CLK_SRC(val)		(((val) & 0x3) << 2)
+#define TIMER_CTL_CLK_SRC_OSC24M		(1)
+#define TIMER_CTL_CLK_PRES(val)		(((val) & 0x7) << 4)
+#define TIMER_CTL_ONESHOT		BIT(7)
+#define TIMER_INTVAL_REG(val)	(0x10 * (val) + 0x14)
+#define TIMER_CNTVAL_REG(val)	(0x10 * (val) + 0x18)
+
+#define TIMER_SYNC_TICKS	3
+
+/*
+ * When we disable a timer, we need to wait at least for 2 cycles of
+ * the timer source clock. We will use for that the clocksource timer
+ * that is already setup and runs at the same frequency than the other
+ * timers, and we never will be disabled.
+ */
+static void sun4i_clkevt_sync(void __iomem *base)
+{
+	u32 old = readl(base + TIMER_CNTVAL_REG(1));
+
+	while ((old - readl(base + TIMER_CNTVAL_REG(1))) < TIMER_SYNC_TICKS)
+		cpu_relax();
+}
+
+static void sun4i_clkevt_time_stop(void __iomem *base, u8 timer)
+{
+	u32 val = readl(base + TIMER_CTL_REG(timer));
+	writel(val & ~TIMER_CTL_ENABLE, base + TIMER_CTL_REG(timer));
+	sun4i_clkevt_sync(base);
+}
+
+static void sun4i_clkevt_time_setup(void __iomem *base, u8 timer,
+				    unsigned long delay)
+{
+	writel(delay, base + TIMER_INTVAL_REG(timer));
+}
+
+static void sun4i_clkevt_time_start(void __iomem *base, u8 timer,
+				    bool periodic)
+{
+	u32 val = readl(base + TIMER_CTL_REG(timer));
+
+	if (periodic)
+		val &= ~TIMER_CTL_ONESHOT;
+	else
+		val |= TIMER_CTL_ONESHOT;
+
+	writel(val | TIMER_CTL_ENABLE | TIMER_CTL_RELOAD,
+	       base + TIMER_CTL_REG(timer));
+}
+
+static int sun4i_clkevt_shutdown(struct clock_event_device *evt)
+{
+	struct timer_of *to = to_timer_of(evt);
+
+	sun4i_clkevt_time_stop(timer_of_base(to), 0);
+
+	return 0;
+}
+
+static int sun4i_clkevt_set_oneshot(struct clock_event_device *evt)
+{
+	struct timer_of *to = to_timer_of(evt);
+
+	sun4i_clkevt_time_stop(timer_of_base(to), 0);
+	sun4i_clkevt_time_start(timer_of_base(to), 0, false);
+
+	return 0;
+}
+
+static int sun4i_clkevt_set_periodic(struct clock_event_device *evt)
+{
+	struct timer_of *to = to_timer_of(evt);
+
+	sun4i_clkevt_time_stop(timer_of_base(to), 0);
+	sun4i_clkevt_time_setup(timer_of_base(to), 0, timer_of_period(to));
+	sun4i_clkevt_time_start(timer_of_base(to), 0, true);
+
+	return 0;
+}
+
+static int sun4i_clkevt_next_event(unsigned long evt,
+				   struct clock_event_device *clkevt)
+{
+	struct timer_of *to = to_timer_of(clkevt);
+
+	sun4i_clkevt_time_stop(timer_of_base(to), 0);
+	sun4i_clkevt_time_setup(timer_of_base(to), 0, evt - TIMER_SYNC_TICKS);
+	sun4i_clkevt_time_start(timer_of_base(to), 0, false);
+
+	return 0;
+}
+
+static void sun4i_timer_clear_interrupt(void __iomem *base)
+{
+	writel(TIMER_IRQ_EN(0), base + TIMER_IRQ_ST_REG);
+}
+
+static irqreturn_t sun4i_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = (struct clock_event_device *)dev_id;
+	struct timer_of *to = to_timer_of(evt);
+
+	sun4i_timer_clear_interrupt(timer_of_base(to));
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static struct timer_of to = {
+	.flags = TIMER_OF_IRQ | TIMER_OF_CLOCK | TIMER_OF_BASE,
+
+	.clkevt = {
+		.name = "sun4i_tick",
+		.rating = 350,
+		.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+		.set_state_shutdown = sun4i_clkevt_shutdown,
+		.set_state_periodic = sun4i_clkevt_set_periodic,
+		.set_state_oneshot = sun4i_clkevt_set_oneshot,
+		.tick_resume = sun4i_clkevt_shutdown,
+		.set_next_event = sun4i_clkevt_next_event,
+		.cpumask = cpu_possible_mask,
+	},
+
+	.of_irq = {
+		.handler = sun4i_timer_interrupt,
+		.flags = IRQF_TIMER | IRQF_IRQPOLL,
+	},
+};
+
+static u64 notrace sun4i_timer_sched_read(void)
+{
+	return ~readl(timer_of_base(&to) + TIMER_CNTVAL_REG(1));
+}
+
+static int __init sun4i_timer_init(struct device_node *node)
+{
+	int ret;
+	u32 val;
+
+	ret = timer_of_init(node, &to);
+	if (ret)
+		return ret;
+
+	writel(~0, timer_of_base(&to) + TIMER_INTVAL_REG(1));
+	writel(TIMER_CTL_ENABLE | TIMER_CTL_RELOAD |
+	       TIMER_CTL_CLK_SRC(TIMER_CTL_CLK_SRC_OSC24M),
+	       timer_of_base(&to) + TIMER_CTL_REG(1));
+
+	/*
+	 * sched_clock_register does not have priorities, and on sun6i and
+	 * later there is a better sched_clock registered by arm_arch_timer.c
+	 */
+	if (of_machine_is_compatible("allwinner,sun4i-a10") ||
+	    of_machine_is_compatible("allwinner,sun5i-a13") ||
+	    of_machine_is_compatible("allwinner,sun5i-a10s"))
+		sched_clock_register(sun4i_timer_sched_read, 32,
+				     timer_of_rate(&to));
+
+	ret = clocksource_mmio_init(timer_of_base(&to) + TIMER_CNTVAL_REG(1),
+				    node->name, timer_of_rate(&to), 350, 32,
+				    clocksource_mmio_readl_down);
+	if (ret) {
+		pr_err("Failed to register clocksource\n");
+		return ret;
+	}
+
+	writel(TIMER_CTL_CLK_SRC(TIMER_CTL_CLK_SRC_OSC24M),
+	       timer_of_base(&to) + TIMER_CTL_REG(0));
+
+	/* Make sure timer is stopped before playing with interrupts */
+	sun4i_clkevt_time_stop(timer_of_base(&to), 0);
+
+	/* clear timer0 interrupt */
+	sun4i_timer_clear_interrupt(timer_of_base(&to));
+
+	clockevents_config_and_register(&to.clkevt, timer_of_rate(&to),
+					TIMER_SYNC_TICKS, 0xffffffff);
+
+	/* Enable timer0 interrupt */
+	val = readl(timer_of_base(&to) + TIMER_IRQ_EN_REG);
+	writel(val | TIMER_IRQ_EN(0), timer_of_base(&to) + TIMER_IRQ_EN_REG);
+
+	return ret;
+}
+TIMER_OF_DECLARE(sun4i, "allwinner,sun4i-a10-timer",
+		       sun4i_timer_init);

drivers/clocksource/tango_xtal.c

@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/clocksource.h>
+#include <linux/sched_clock.h>
+#include <linux/of_address.h>
+#include <linux/printk.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/clk.h>
+
+static void __iomem *xtal_in_cnt;
+static struct delay_timer delay_timer;
+
+static unsigned long notrace read_xtal_counter(void)
+{
+	return readl_relaxed(xtal_in_cnt);
+}
+
+static u64 notrace read_sched_clock(void)
+{
+	return read_xtal_counter();
+}
+
+static int __init tango_clocksource_init(struct device_node *np)
+{
+	struct clk *clk;
+	int xtal_freq, ret;
+
+	xtal_in_cnt = of_iomap(np, 0);
+	if (xtal_in_cnt == NULL) {
+		pr_err("%pOF: invalid address\n", np);
+		return -ENXIO;
+	}
+
+	clk = of_clk_get(np, 0);
+	if (IS_ERR(clk)) {
+		pr_err("%pOF: invalid clock\n", np);
+		return PTR_ERR(clk);
+	}
+
+	xtal_freq = clk_get_rate(clk);
+	delay_timer.freq = xtal_freq;
+	delay_timer.read_current_timer = read_xtal_counter;
+
+	ret = clocksource_mmio_init(xtal_in_cnt, "tango-xtal", xtal_freq, 350,
+				    32, clocksource_mmio_readl_up);
+	if (ret) {
+		pr_err("%pOF: registration failed\n", np);
+		return ret;
+	}
+
+	sched_clock_register(read_sched_clock, 32, xtal_freq);
+	register_current_timer_delay(&delay_timer);
+
+	return 0;
+}
+
+TIMER_OF_DECLARE(tango, "sigma,tick-counter", tango_clocksource_init);

drivers/clocksource/tcb_clksrc.c

@@ -0,0 +1,433 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/init.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/ioport.h>
+#include <linux/io.h>
+#include <linux/platform_device.h>
+#include <linux/syscore_ops.h>
+#include <linux/atmel_tc.h>
+
+
+/*
+ * We're configured to use a specific TC block, one that's not hooked
+ * up to external hardware, to provide a time solution:
+ *
+ *   - Two channels combine to create a free-running 32 bit counter
+ *     with a base rate of 5+ MHz, packaged as a clocksource (with
+ *     resolution better than 200 nsec).
+ *   - Some chips support 32 bit counter. A single channel is used for
+ *     this 32 bit free-running counter. the second channel is not used.
+ *
+ *   - The third channel may be used to provide a 16-bit clockevent
+ *     source, used in either periodic or oneshot mode.  This runs
+ *     at 32 KiHZ, and can handle delays of up to two seconds.
+ *
+ * A boot clocksource and clockevent source are also currently needed,
+ * unless the relevant platforms (ARM/AT91, AVR32/AT32) are changed so
+ * this code can be used when init_timers() is called, well before most
+ * devices are set up.  (Some low end AT91 parts, which can run uClinux,
+ * have only the timers in one TC block... they currently don't support
+ * the tclib code, because of that initialization issue.)
+ *
+ * REVISIT behavior during system suspend states... we should disable
+ * all clocks and save the power.  Easily done for clockevent devices,
+ * but clocksources won't necessarily get the needed notifications.
+ * For deeper system sleep states, this will be mandatory...
+ */
+
+static void __iomem *tcaddr;
+static struct
+{
+	u32 cmr;
+	u32 imr;
+	u32 rc;
+	bool clken;
+} tcb_cache[3];
+static u32 bmr_cache;
+
+static u64 tc_get_cycles(struct clocksource *cs)
+{
+	unsigned long	flags;
+	u32		lower, upper;
+
+	raw_local_irq_save(flags);
+	do {
+		upper = readl_relaxed(tcaddr + ATMEL_TC_REG(1, CV));
+		lower = readl_relaxed(tcaddr + ATMEL_TC_REG(0, CV));
+	} while (upper != readl_relaxed(tcaddr + ATMEL_TC_REG(1, CV)));
+
+	raw_local_irq_restore(flags);
+	return (upper << 16) | lower;
+}
+
+static u64 tc_get_cycles32(struct clocksource *cs)
+{
+	return readl_relaxed(tcaddr + ATMEL_TC_REG(0, CV));
+}
+
+void tc_clksrc_suspend(struct clocksource *cs)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(tcb_cache); i++) {
+		tcb_cache[i].cmr = readl(tcaddr + ATMEL_TC_REG(i, CMR));
+		tcb_cache[i].imr = readl(tcaddr + ATMEL_TC_REG(i, IMR));
+		tcb_cache[i].rc = readl(tcaddr + ATMEL_TC_REG(i, RC));
+		tcb_cache[i].clken = !!(readl(tcaddr + ATMEL_TC_REG(i, SR)) &
+					ATMEL_TC_CLKSTA);
+	}
+
+	bmr_cache = readl(tcaddr + ATMEL_TC_BMR);
+}
+
+void tc_clksrc_resume(struct clocksource *cs)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(tcb_cache); i++) {
+		/* Restore registers for the channel, RA and RB are not used  */
+		writel(tcb_cache[i].cmr, tcaddr + ATMEL_TC_REG(i, CMR));
+		writel(tcb_cache[i].rc, tcaddr + ATMEL_TC_REG(i, RC));
+		writel(0, tcaddr + ATMEL_TC_REG(i, RA));
+		writel(0, tcaddr + ATMEL_TC_REG(i, RB));
+		/* Disable all the interrupts */
+		writel(0xff, tcaddr + ATMEL_TC_REG(i, IDR));
+		/* Reenable interrupts that were enabled before suspending */
+		writel(tcb_cache[i].imr, tcaddr + ATMEL_TC_REG(i, IER));
+		/* Start the clock if it was used */
+		if (tcb_cache[i].clken)
+			writel(ATMEL_TC_CLKEN, tcaddr + ATMEL_TC_REG(i, CCR));
+	}
+
+	/* Dual channel, chain channels */
+	writel(bmr_cache, tcaddr + ATMEL_TC_BMR);
+	/* Finally, trigger all the channels*/
+	writel(ATMEL_TC_SYNC, tcaddr + ATMEL_TC_BCR);
+}
+
+static struct clocksource clksrc = {
+	.name           = "tcb_clksrc",
+	.rating         = 200,
+	.read           = tc_get_cycles,
+	.mask           = CLOCKSOURCE_MASK(32),
+	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
+	.suspend	= tc_clksrc_suspend,
+	.resume		= tc_clksrc_resume,
+};
+
+#ifdef CONFIG_GENERIC_CLOCKEVENTS
+
+struct tc_clkevt_device {
+	struct clock_event_device	clkevt;
+	struct clk			*clk;
+	void __iomem			*regs;
+};
+
+static struct tc_clkevt_device *to_tc_clkevt(struct clock_event_device *clkevt)
+{
+	return container_of(clkevt, struct tc_clkevt_device, clkevt);
+}
+
+/* For now, we always use the 32K clock ... this optimizes for NO_HZ,
+ * because using one of the divided clocks would usually mean the
+ * tick rate can never be less than several dozen Hz (vs 0.5 Hz).
+ *
+ * A divided clock could be good for high resolution timers, since
+ * 30.5 usec resolution can seem "low".
+ */
+static u32 timer_clock;
+
+static int tc_shutdown(struct clock_event_device *d)
+{
+	struct tc_clkevt_device *tcd = to_tc_clkevt(d);
+	void __iomem		*regs = tcd->regs;
+
+	writel(0xff, regs + ATMEL_TC_REG(2, IDR));
+	writel(ATMEL_TC_CLKDIS, regs + ATMEL_TC_REG(2, CCR));
+	if (!clockevent_state_detached(d))
+		clk_disable(tcd->clk);
+
+	return 0;
+}
+
+static int tc_set_oneshot(struct clock_event_device *d)
+{
+	struct tc_clkevt_device *tcd = to_tc_clkevt(d);
+	void __iomem		*regs = tcd->regs;
+
+	if (clockevent_state_oneshot(d) || clockevent_state_periodic(d))
+		tc_shutdown(d);
+
+	clk_enable(tcd->clk);
+
+	/* slow clock, count up to RC, then irq and stop */
+	writel(timer_clock | ATMEL_TC_CPCSTOP | ATMEL_TC_WAVE |
+		     ATMEL_TC_WAVESEL_UP_AUTO, regs + ATMEL_TC_REG(2, CMR));
+	writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER));
+
+	/* set_next_event() configures and starts the timer */
+	return 0;
+}
+
+static int tc_set_periodic(struct clock_event_device *d)
+{
+	struct tc_clkevt_device *tcd = to_tc_clkevt(d);
+	void __iomem		*regs = tcd->regs;
+
+	if (clockevent_state_oneshot(d) || clockevent_state_periodic(d))
+		tc_shutdown(d);
+
+	/* By not making the gentime core emulate periodic mode on top
+	 * of oneshot, we get lower overhead and improved accuracy.
+	 */
+	clk_enable(tcd->clk);
+
+	/* slow clock, count up to RC, then irq and restart */
+	writel(timer_clock | ATMEL_TC_WAVE | ATMEL_TC_WAVESEL_UP_AUTO,
+		     regs + ATMEL_TC_REG(2, CMR));
+	writel((32768 + HZ / 2) / HZ, tcaddr + ATMEL_TC_REG(2, RC));
+
+	/* Enable clock and interrupts on RC compare */
+	writel(ATMEL_TC_CPCS, regs + ATMEL_TC_REG(2, IER));
+
+	/* go go gadget! */
+	writel(ATMEL_TC_CLKEN | ATMEL_TC_SWTRG, regs +
+		     ATMEL_TC_REG(2, CCR));
+	return 0;
+}
+
+static int tc_next_event(unsigned long delta, struct clock_event_device *d)
+{
+	writel_relaxed(delta, tcaddr + ATMEL_TC_REG(2, RC));
+
+	/* go go gadget! */
+	writel_relaxed(ATMEL_TC_CLKEN | ATMEL_TC_SWTRG,
+			tcaddr + ATMEL_TC_REG(2, CCR));
+	return 0;
+}
+
+static struct tc_clkevt_device clkevt = {
+	.clkevt	= {
+		.name			= "tc_clkevt",
+		.features		= CLOCK_EVT_FEAT_PERIODIC |
+					  CLOCK_EVT_FEAT_ONESHOT,
+		/* Should be lower than at91rm9200's system timer */
+		.rating			= 125,
+		.set_next_event		= tc_next_event,
+		.set_state_shutdown	= tc_shutdown,
+		.set_state_periodic	= tc_set_periodic,
+		.set_state_oneshot	= tc_set_oneshot,
+	},
+};
+
+static irqreturn_t ch2_irq(int irq, void *handle)
+{
+	struct tc_clkevt_device	*dev = handle;
+	unsigned int		sr;
+
+	sr = readl_relaxed(dev->regs + ATMEL_TC_REG(2, SR));
+	if (sr & ATMEL_TC_CPCS) {
+		dev->clkevt.event_handler(&dev->clkevt);
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
+}
+
+static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx)
+{
+	int ret;
+	struct clk *t2_clk = tc->clk[2];
+	int irq = tc->irq[2];
+
+	ret = clk_prepare_enable(tc->slow_clk);
+	if (ret)
+		return ret;
+
+	/* try to enable t2 clk to avoid future errors in mode change */
+	ret = clk_prepare_enable(t2_clk);
+	if (ret) {
+		clk_disable_unprepare(tc->slow_clk);
+		return ret;
+	}
+
+	clk_disable(t2_clk);
+
+	clkevt.regs = tc->regs;
+	clkevt.clk = t2_clk;
+
+	timer_clock = clk32k_divisor_idx;
+
+	clkevt.clkevt.cpumask = cpumask_of(0);
+
+	ret = request_irq(irq, ch2_irq, IRQF_TIMER, "tc_clkevt", &clkevt);
+	if (ret) {
+		clk_unprepare(t2_clk);
+		clk_disable_unprepare(tc->slow_clk);
+		return ret;
+	}
+
+	clockevents_config_and_register(&clkevt.clkevt, 32768, 1, 0xffff);
+
+	return ret;
+}
+
+#else /* !CONFIG_GENERIC_CLOCKEVENTS */
+
+static int __init setup_clkevents(struct atmel_tc *tc, int clk32k_divisor_idx)
+{
+	/* NOTHING */
+	return 0;
+}
+
+#endif
+
+static void __init tcb_setup_dual_chan(struct atmel_tc *tc, int mck_divisor_idx)
+{
+	/* channel 0:  waveform mode, input mclk/8, clock TIOA0 on overflow */
+	writel(mck_divisor_idx			/* likely divide-by-8 */
+			| ATMEL_TC_WAVE
+			| ATMEL_TC_WAVESEL_UP		/* free-run */
+			| ATMEL_TC_ACPA_SET		/* TIOA0 rises at 0 */
+			| ATMEL_TC_ACPC_CLEAR,		/* (duty cycle 50%) */
+			tcaddr + ATMEL_TC_REG(0, CMR));
+	writel(0x0000, tcaddr + ATMEL_TC_REG(0, RA));
+	writel(0x8000, tcaddr + ATMEL_TC_REG(0, RC));
+	writel(0xff, tcaddr + ATMEL_TC_REG(0, IDR));	/* no irqs */
+	writel(ATMEL_TC_CLKEN, tcaddr + ATMEL_TC_REG(0, CCR));
+
+	/* channel 1:  waveform mode, input TIOA0 */
+	writel(ATMEL_TC_XC1			/* input: TIOA0 */
+			| ATMEL_TC_WAVE
+			| ATMEL_TC_WAVESEL_UP,		/* free-run */
+			tcaddr + ATMEL_TC_REG(1, CMR));
+	writel(0xff, tcaddr + ATMEL_TC_REG(1, IDR));	/* no irqs */
+	writel(ATMEL_TC_CLKEN, tcaddr + ATMEL_TC_REG(1, CCR));
+
+	/* chain channel 0 to channel 1*/
+	writel(ATMEL_TC_TC1XC1S_TIOA0, tcaddr + ATMEL_TC_BMR);
+	/* then reset all the timers */
+	writel(ATMEL_TC_SYNC, tcaddr + ATMEL_TC_BCR);
+}
+
+static void __init tcb_setup_single_chan(struct atmel_tc *tc, int mck_divisor_idx)
+{
+	/* channel 0:  waveform mode, input mclk/8 */
+	writel(mck_divisor_idx			/* likely divide-by-8 */
+			| ATMEL_TC_WAVE
+			| ATMEL_TC_WAVESEL_UP,		/* free-run */
+			tcaddr + ATMEL_TC_REG(0, CMR));
+	writel(0xff, tcaddr + ATMEL_TC_REG(0, IDR));	/* no irqs */
+	writel(ATMEL_TC_CLKEN, tcaddr + ATMEL_TC_REG(0, CCR));
+
+	/* then reset all the timers */
+	writel(ATMEL_TC_SYNC, tcaddr + ATMEL_TC_BCR);
+}
+
+static int __init tcb_clksrc_init(void)
+{
+	static char bootinfo[] __initdata
+		= KERN_DEBUG "%s: tc%d at %d.%03d MHz\n";
+
+	struct platform_device *pdev;
+	struct atmel_tc *tc;
+	struct clk *t0_clk;
+	u32 rate, divided_rate = 0;
+	int best_divisor_idx = -1;
+	int clk32k_divisor_idx = -1;
+	int i;
+	int ret;
+
+	tc = atmel_tc_alloc(CONFIG_ATMEL_TCB_CLKSRC_BLOCK);
+	if (!tc) {
+		pr_debug("can't alloc TC for clocksource\n");
+		return -ENODEV;
+	}
+	tcaddr = tc->regs;
+	pdev = tc->pdev;
+
+	t0_clk = tc->clk[0];
+	ret = clk_prepare_enable(t0_clk);
+	if (ret) {
+		pr_debug("can't enable T0 clk\n");
+		goto err_free_tc;
+	}
+
+	/* How fast will we be counting?  Pick something over 5 MHz.  */
+	rate = (u32) clk_get_rate(t0_clk);
+	for (i = 0; i < 5; i++) {
+		unsigned divisor = atmel_tc_divisors[i];
+		unsigned tmp;
+
+		/* remember 32 KiHz clock for later */
+		if (!divisor) {
+			clk32k_divisor_idx = i;
+			continue;
+		}
+
+		tmp = rate / divisor;
+		pr_debug("TC: %u / %-3u [%d] --> %u\n", rate, divisor, i, tmp);
+		if (best_divisor_idx > 0) {
+			if (tmp < 5 * 1000 * 1000)
+				continue;
+		}
+		divided_rate = tmp;
+		best_divisor_idx = i;
+	}
+
+
+	printk(bootinfo, clksrc.name, CONFIG_ATMEL_TCB_CLKSRC_BLOCK,
+			divided_rate / 1000000,
+			((divided_rate % 1000000) + 500) / 1000);
+
+	if (tc->tcb_config && tc->tcb_config->counter_width == 32) {
+		/* use apropriate function to read 32 bit counter */
+		clksrc.read = tc_get_cycles32;
+		/* setup ony channel 0 */
+		tcb_setup_single_chan(tc, best_divisor_idx);
+	} else {
+		/* tclib will give us three clocks no matter what the
+		 * underlying platform supports.
+		 */
+		ret = clk_prepare_enable(tc->clk[1]);
+		if (ret) {
+			pr_debug("can't enable T1 clk\n");
+			goto err_disable_t0;
+		}
+		/* setup both channel 0 & 1 */
+		tcb_setup_dual_chan(tc, best_divisor_idx);
+	}
+
+	/* and away we go! */
+	ret = clocksource_register_hz(&clksrc, divided_rate);
+	if (ret)
+		goto err_disable_t1;
+
+	/* channel 2:  periodic and oneshot timer support */
+	ret = setup_clkevents(tc, clk32k_divisor_idx);
+	if (ret)
+		goto err_unregister_clksrc;
+
+	return 0;
+
+err_unregister_clksrc:
+	clocksource_unregister(&clksrc);
+
+err_disable_t1:
+	if (!tc->tcb_config || tc->tcb_config->counter_width != 32)
+		clk_disable_unprepare(tc->clk[1]);
+
+err_disable_t0:
+	clk_disable_unprepare(t0_clk);
+
+err_free_tc:
+	atmel_tc_free(tc);
+	return ret;
+}
+arch_initcall(tcb_clksrc_init);

drivers/clocksource/tegra20_timer.c

@@ -0,0 +1,264 @@
+/*
+ * Copyright (C) 2010 Google, Inc.
+ *
+ * Author:
+ *	Colin Cross <ccross@google.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/err.h>
+#include <linux/time.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+#include <linux/delay.h>
+
+#include <asm/mach/time.h>
+#include <asm/smp_twd.h>
+
+#define RTC_SECONDS            0x08
+#define RTC_SHADOW_SECONDS     0x0c
+#define RTC_MILLISECONDS       0x10
+
+#define TIMERUS_CNTR_1US 0x10
+#define TIMERUS_USEC_CFG 0x14
+#define TIMERUS_CNTR_FREEZE 0x4c
+
+#define TIMER1_BASE 0x0
+#define TIMER2_BASE 0x8
+#define TIMER3_BASE 0x50
+#define TIMER4_BASE 0x58
+
+#define TIMER_PTV 0x0
+#define TIMER_PCR 0x4
+
+static void __iomem *timer_reg_base;
+static void __iomem *rtc_base;
+
+static struct timespec64 persistent_ts;
+static u64 persistent_ms, last_persistent_ms;
+
+static struct delay_timer tegra_delay_timer;
+
+#define timer_writel(value, reg) \
+	writel_relaxed(value, timer_reg_base + (reg))
+#define timer_readl(reg) \
+	readl_relaxed(timer_reg_base + (reg))
+
+static int tegra_timer_set_next_event(unsigned long cycles,
+					 struct clock_event_device *evt)
+{
+	u32 reg;
+
+	reg = 0x80000000 | ((cycles > 1) ? (cycles-1) : 0);
+	timer_writel(reg, TIMER3_BASE + TIMER_PTV);
+
+	return 0;
+}
+
+static inline void timer_shutdown(struct clock_event_device *evt)
+{
+	timer_writel(0, TIMER3_BASE + TIMER_PTV);
+}
+
+static int tegra_timer_shutdown(struct clock_event_device *evt)
+{
+	timer_shutdown(evt);
+	return 0;
+}
+
+static int tegra_timer_set_periodic(struct clock_event_device *evt)
+{
+	u32 reg = 0xC0000000 | ((1000000 / HZ) - 1);
+
+	timer_shutdown(evt);
+	timer_writel(reg, TIMER3_BASE + TIMER_PTV);
+	return 0;
+}
+
+static struct clock_event_device tegra_clockevent = {
+	.name			= "timer0",
+	.rating			= 300,
+	.features		= CLOCK_EVT_FEAT_ONESHOT |
+				  CLOCK_EVT_FEAT_PERIODIC |
+				  CLOCK_EVT_FEAT_DYNIRQ,
+	.set_next_event		= tegra_timer_set_next_event,
+	.set_state_shutdown	= tegra_timer_shutdown,
+	.set_state_periodic	= tegra_timer_set_periodic,
+	.set_state_oneshot	= tegra_timer_shutdown,
+	.tick_resume		= tegra_timer_shutdown,
+};
+
+static u64 notrace tegra_read_sched_clock(void)
+{
+	return timer_readl(TIMERUS_CNTR_1US);
+}
+
+/*
+ * tegra_rtc_read - Reads the Tegra RTC registers
+ * Care must be taken that this funciton is not called while the
+ * tegra_rtc driver could be executing to avoid race conditions
+ * on the RTC shadow register
+ */
+static u64 tegra_rtc_read_ms(void)
+{
+	u32 ms = readl(rtc_base + RTC_MILLISECONDS);
+	u32 s = readl(rtc_base + RTC_SHADOW_SECONDS);
+	return (u64)s * MSEC_PER_SEC + ms;
+}
+
+/*
+ * tegra_read_persistent_clock64 -  Return time from a persistent clock.
+ *
+ * Reads the time from a source which isn't disabled during PM, the
+ * 32k sync timer.  Convert the cycles elapsed since last read into
+ * nsecs and adds to a monotonically increasing timespec64.
+ * Care must be taken that this funciton is not called while the
+ * tegra_rtc driver could be executing to avoid race conditions
+ * on the RTC shadow register
+ */
+static void tegra_read_persistent_clock64(struct timespec64 *ts)
+{
+	u64 delta;
+
+	last_persistent_ms = persistent_ms;
+	persistent_ms = tegra_rtc_read_ms();
+	delta = persistent_ms - last_persistent_ms;
+
+	timespec64_add_ns(&persistent_ts, delta * NSEC_PER_MSEC);
+	*ts = persistent_ts;
+}
+
+static unsigned long tegra_delay_timer_read_counter_long(void)
+{
+	return readl(timer_reg_base + TIMERUS_CNTR_1US);
+}
+
+static irqreturn_t tegra_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = (struct clock_event_device *)dev_id;
+	timer_writel(1<<30, TIMER3_BASE + TIMER_PCR);
+	evt->event_handler(evt);
+	return IRQ_HANDLED;
+}
+
+static struct irqaction tegra_timer_irq = {
+	.name		= "timer0",
+	.flags		= IRQF_TIMER | IRQF_TRIGGER_HIGH,
+	.handler	= tegra_timer_interrupt,
+	.dev_id		= &tegra_clockevent,
+};
+
+static int __init tegra20_init_timer(struct device_node *np)
+{
+	struct clk *clk;
+	unsigned long rate;
+	int ret;
+
+	timer_reg_base = of_iomap(np, 0);
+	if (!timer_reg_base) {
+		pr_err("Can't map timer registers\n");
+		return -ENXIO;
+	}
+
+	tegra_timer_irq.irq = irq_of_parse_and_map(np, 2);
+	if (tegra_timer_irq.irq <= 0) {
+		pr_err("Failed to map timer IRQ\n");
+		return -EINVAL;
+	}
+
+	clk = of_clk_get(np, 0);
+	if (IS_ERR(clk)) {
+		pr_warn("Unable to get timer clock. Assuming 12Mhz input clock.\n");
+		rate = 12000000;
+	} else {
+		clk_prepare_enable(clk);
+		rate = clk_get_rate(clk);
+	}
+
+	switch (rate) {
+	case 12000000:
+		timer_writel(0x000b, TIMERUS_USEC_CFG);
+		break;
+	case 13000000:
+		timer_writel(0x000c, TIMERUS_USEC_CFG);
+		break;
+	case 19200000:
+		timer_writel(0x045f, TIMERUS_USEC_CFG);
+		break;
+	case 26000000:
+		timer_writel(0x0019, TIMERUS_USEC_CFG);
+		break;
+	default:
+		WARN(1, "Unknown clock rate");
+	}
+
+	sched_clock_register(tegra_read_sched_clock, 32, 1000000);
+
+	ret = clocksource_mmio_init(timer_reg_base + TIMERUS_CNTR_1US,
+				    "timer_us", 1000000, 300, 32,
+				    clocksource_mmio_readl_up);
+	if (ret) {
+		pr_err("Failed to register clocksource\n");
+		return ret;
+	}
+
+	tegra_delay_timer.read_current_timer =
+			tegra_delay_timer_read_counter_long;
+	tegra_delay_timer.freq = 1000000;
+	register_current_timer_delay(&tegra_delay_timer);
+
+	ret = setup_irq(tegra_timer_irq.irq, &tegra_timer_irq);
+	if (ret) {
+		pr_err("Failed to register timer IRQ: %d\n", ret);
+		return ret;
+	}
+
+	tegra_clockevent.cpumask = cpu_possible_mask;
+	tegra_clockevent.irq = tegra_timer_irq.irq;
+	clockevents_config_and_register(&tegra_clockevent, 1000000,
+					0x1, 0x1fffffff);
+
+	return 0;
+}
+TIMER_OF_DECLARE(tegra20_timer, "nvidia,tegra20-timer", tegra20_init_timer);
+
+static int __init tegra20_init_rtc(struct device_node *np)
+{
+	struct clk *clk;
+
+	rtc_base = of_iomap(np, 0);
+	if (!rtc_base) {
+		pr_err("Can't map RTC registers\n");
+		return -ENXIO;
+	}
+
+	/*
+	 * rtc registers are used by read_persistent_clock, keep the rtc clock
+	 * enabled
+	 */
+	clk = of_clk_get(np, 0);
+	if (IS_ERR(clk))
+		pr_warn("Unable to get rtc-tegra clock\n");
+	else
+		clk_prepare_enable(clk);
+
+	return register_persistent_clock(tegra_read_persistent_clock64);
+}
+TIMER_OF_DECLARE(tegra20_rtc, "nvidia,tegra20-rtc", tegra20_init_rtc);

drivers/clocksource/time-armada-370-xp.c

@@ -0,0 +1,416 @@
+/*
+ * Marvell Armada 370/XP SoC timer handling.
+ *
+ * Copyright (C) 2012 Marvell
+ *
+ * Lior Amsalem <alior@marvell.com>
+ * Gregory CLEMENT <gregory.clement@free-electrons.com>
+ * Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ *
+ * Timer 0 is used as free-running clocksource, while timer 1 is
+ * used as clock_event_device.
+ *
+ * ---
+ * Clocksource driver for Armada 370 and Armada XP SoC.
+ * This driver implements one compatible string for each SoC, given
+ * each has its own characteristics:
+ *
+ *   * Armada 370 has no 25 MHz fixed timer.
+ *
+ *   * Armada XP cannot work properly without such 25 MHz fixed timer as
+ *     doing otherwise leads to using a clocksource whose frequency varies
+ *     when doing cpufreq frequency changes.
+ *
+ * See Documentation/devicetree/bindings/timer/marvell,armada-370-xp-timer.txt
+ */
+
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/kernel.h>
+#include <linux/clk.h>
+#include <linux/cpu.h>
+#include <linux/timer.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/irq.h>
+#include <linux/module.h>
+#include <linux/sched_clock.h>
+#include <linux/percpu.h>
+#include <linux/syscore_ops.h>
+
+#include <asm/delay.h>
+
+/*
+ * Timer block registers.
+ */
+#define TIMER_CTRL_OFF		0x0000
+#define  TIMER0_EN		 BIT(0)
+#define  TIMER0_RELOAD_EN	 BIT(1)
+#define  TIMER0_25MHZ            BIT(11)
+#define  TIMER0_DIV(div)         ((div) << 19)
+#define  TIMER1_EN		 BIT(2)
+#define  TIMER1_RELOAD_EN	 BIT(3)
+#define  TIMER1_25MHZ            BIT(12)
+#define  TIMER1_DIV(div)         ((div) << 22)
+#define TIMER_EVENTS_STATUS	0x0004
+#define  TIMER0_CLR_MASK         (~0x1)
+#define  TIMER1_CLR_MASK         (~0x100)
+#define TIMER0_RELOAD_OFF	0x0010
+#define TIMER0_VAL_OFF		0x0014
+#define TIMER1_RELOAD_OFF	0x0018
+#define TIMER1_VAL_OFF		0x001c
+
+#define LCL_TIMER_EVENTS_STATUS	0x0028
+/* Global timers are connected to the coherency fabric clock, and the
+   below divider reduces their incrementing frequency. */
+#define TIMER_DIVIDER_SHIFT     5
+#define TIMER_DIVIDER           (1 << TIMER_DIVIDER_SHIFT)
+
+/*
+ * SoC-specific data.
+ */
+static void __iomem *timer_base, *local_base;
+static unsigned int timer_clk;
+static bool timer25Mhz = true;
+static u32 enable_mask;
+
+/*
+ * Number of timer ticks per jiffy.
+ */
+static u32 ticks_per_jiffy;
+
+static struct clock_event_device __percpu *armada_370_xp_evt;
+
+static void local_timer_ctrl_clrset(u32 clr, u32 set)
+{
+	writel((readl(local_base + TIMER_CTRL_OFF) & ~clr) | set,
+		local_base + TIMER_CTRL_OFF);
+}
+
+static u64 notrace armada_370_xp_read_sched_clock(void)
+{
+	return ~readl(timer_base + TIMER0_VAL_OFF);
+}
+
+/*
+ * Clockevent handling.
+ */
+static int
+armada_370_xp_clkevt_next_event(unsigned long delta,
+				struct clock_event_device *dev)
+{
+	/*
+	 * Clear clockevent timer interrupt.
+	 */
+	writel(TIMER0_CLR_MASK, local_base + LCL_TIMER_EVENTS_STATUS);
+
+	/*
+	 * Setup new clockevent timer value.
+	 */
+	writel(delta, local_base + TIMER0_VAL_OFF);
+
+	/*
+	 * Enable the timer.
+	 */
+	local_timer_ctrl_clrset(TIMER0_RELOAD_EN, enable_mask);
+	return 0;
+}
+
+static int armada_370_xp_clkevt_shutdown(struct clock_event_device *evt)
+{
+	/*
+	 * Disable timer.
+	 */
+	local_timer_ctrl_clrset(TIMER0_EN, 0);
+
+	/*
+	 * ACK pending timer interrupt.
+	 */
+	writel(TIMER0_CLR_MASK, local_base + LCL_TIMER_EVENTS_STATUS);
+	return 0;
+}
+
+static int armada_370_xp_clkevt_set_periodic(struct clock_event_device *evt)
+{
+	/*
+	 * Setup timer to fire at 1/HZ intervals.
+	 */
+	writel(ticks_per_jiffy - 1, local_base + TIMER0_RELOAD_OFF);
+	writel(ticks_per_jiffy - 1, local_base + TIMER0_VAL_OFF);
+
+	/*
+	 * Enable timer.
+	 */
+	local_timer_ctrl_clrset(0, TIMER0_RELOAD_EN | enable_mask);
+	return 0;
+}
+
+static int armada_370_xp_clkevt_irq;
+
+static irqreturn_t armada_370_xp_timer_interrupt(int irq, void *dev_id)
+{
+	/*
+	 * ACK timer interrupt and call event handler.
+	 */
+	struct clock_event_device *evt = dev_id;
+
+	writel(TIMER0_CLR_MASK, local_base + LCL_TIMER_EVENTS_STATUS);
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+/*
+ * Setup the local clock events for a CPU.
+ */
+static int armada_370_xp_timer_starting_cpu(unsigned int cpu)
+{
+	struct clock_event_device *evt = per_cpu_ptr(armada_370_xp_evt, cpu);
+	u32 clr = 0, set = 0;
+
+	if (timer25Mhz)
+		set = TIMER0_25MHZ;
+	else
+		clr = TIMER0_25MHZ;
+	local_timer_ctrl_clrset(clr, set);
+
+	evt->name		= "armada_370_xp_per_cpu_tick",
+	evt->features		= CLOCK_EVT_FEAT_ONESHOT |
+				  CLOCK_EVT_FEAT_PERIODIC;
+	evt->shift		= 32,
+	evt->rating		= 300,
+	evt->set_next_event	= armada_370_xp_clkevt_next_event,
+	evt->set_state_shutdown	= armada_370_xp_clkevt_shutdown;
+	evt->set_state_periodic	= armada_370_xp_clkevt_set_periodic;
+	evt->set_state_oneshot	= armada_370_xp_clkevt_shutdown;
+	evt->tick_resume	= armada_370_xp_clkevt_shutdown;
+	evt->irq		= armada_370_xp_clkevt_irq;
+	evt->cpumask		= cpumask_of(cpu);
+
+	clockevents_config_and_register(evt, timer_clk, 1, 0xfffffffe);
+	enable_percpu_irq(evt->irq, 0);
+
+	return 0;
+}
+
+static int armada_370_xp_timer_dying_cpu(unsigned int cpu)
+{
+	struct clock_event_device *evt = per_cpu_ptr(armada_370_xp_evt, cpu);
+
+	evt->set_state_shutdown(evt);
+	disable_percpu_irq(evt->irq);
+	return 0;
+}
+
+static u32 timer0_ctrl_reg, timer0_local_ctrl_reg;
+
+static int armada_370_xp_timer_suspend(void)
+{
+	timer0_ctrl_reg = readl(timer_base + TIMER_CTRL_OFF);
+	timer0_local_ctrl_reg = readl(local_base + TIMER_CTRL_OFF);
+	return 0;
+}
+
+static void armada_370_xp_timer_resume(void)
+{
+	writel(0xffffffff, timer_base + TIMER0_VAL_OFF);
+	writel(0xffffffff, timer_base + TIMER0_RELOAD_OFF);
+	writel(timer0_ctrl_reg, timer_base + TIMER_CTRL_OFF);
+	writel(timer0_local_ctrl_reg, local_base + TIMER_CTRL_OFF);
+}
+
+static struct syscore_ops armada_370_xp_timer_syscore_ops = {
+	.suspend	= armada_370_xp_timer_suspend,
+	.resume		= armada_370_xp_timer_resume,
+};
+
+static unsigned long armada_370_delay_timer_read(void)
+{
+	return ~readl(timer_base + TIMER0_VAL_OFF);
+}
+
+static struct delay_timer armada_370_delay_timer = {
+	.read_current_timer = armada_370_delay_timer_read,
+};
+
+static int __init armada_370_xp_timer_common_init(struct device_node *np)
+{
+	u32 clr = 0, set = 0;
+	int res;
+
+	timer_base = of_iomap(np, 0);
+	if (!timer_base) {
+		pr_err("Failed to iomap\n");
+		return -ENXIO;
+	}
+
+	local_base = of_iomap(np, 1);
+	if (!local_base) {
+		pr_err("Failed to iomap\n");
+		return -ENXIO;
+	}
+
+	if (timer25Mhz) {
+		set = TIMER0_25MHZ;		
+		enable_mask = TIMER0_EN;
+	} else {
+		clr = TIMER0_25MHZ;
+		enable_mask = TIMER0_EN | TIMER0_DIV(TIMER_DIVIDER_SHIFT);
+	}
+	atomic_io_modify(timer_base + TIMER_CTRL_OFF, clr | set, set);
+	local_timer_ctrl_clrset(clr, set);
+
+	/*
+	 * We use timer 0 as clocksource, and private(local) timer 0
+	 * for clockevents
+	 */
+	armada_370_xp_clkevt_irq = irq_of_parse_and_map(np, 4);
+
+	ticks_per_jiffy = (timer_clk + HZ / 2) / HZ;
+
+	/*
+	 * Setup free-running clocksource timer (interrupts
+	 * disabled).
+	 */
+	writel(0xffffffff, timer_base + TIMER0_VAL_OFF);
+	writel(0xffffffff, timer_base + TIMER0_RELOAD_OFF);
+
+	atomic_io_modify(timer_base + TIMER_CTRL_OFF,
+		TIMER0_RELOAD_EN | enable_mask,
+		TIMER0_RELOAD_EN | enable_mask);
+
+	armada_370_delay_timer.freq = timer_clk;
+	register_current_timer_delay(&armada_370_delay_timer);
+
+	/*
+	 * Set scale and timer for sched_clock.
+	 */
+	sched_clock_register(armada_370_xp_read_sched_clock, 32, timer_clk);
+
+	res = clocksource_mmio_init(timer_base + TIMER0_VAL_OFF,
+				    "armada_370_xp_clocksource",
+				    timer_clk, 300, 32, clocksource_mmio_readl_down);
+	if (res) {
+		pr_err("Failed to initialize clocksource mmio\n");
+		return res;
+	}
+
+	armada_370_xp_evt = alloc_percpu(struct clock_event_device);
+	if (!armada_370_xp_evt)
+		return -ENOMEM;
+
+	/*
+	 * Setup clockevent timer (interrupt-driven).
+	 */
+	res = request_percpu_irq(armada_370_xp_clkevt_irq,
+				armada_370_xp_timer_interrupt,
+				"armada_370_xp_per_cpu_tick",
+				armada_370_xp_evt);
+	/* Immediately configure the timer on the boot CPU */
+	if (res) {
+		pr_err("Failed to request percpu irq\n");
+		return res;
+	}
+
+	res = cpuhp_setup_state(CPUHP_AP_ARMADA_TIMER_STARTING,
+				"clockevents/armada:starting",
+				armada_370_xp_timer_starting_cpu,
+				armada_370_xp_timer_dying_cpu);
+	if (res) {
+		pr_err("Failed to setup hotplug state and timer\n");
+		return res;
+	}
+
+	register_syscore_ops(&armada_370_xp_timer_syscore_ops);
+	
+	return 0;
+}
+
+static int __init armada_xp_timer_init(struct device_node *np)
+{
+	struct clk *clk = of_clk_get_by_name(np, "fixed");
+	int ret;
+
+	if (IS_ERR(clk)) {
+		pr_err("Failed to get clock\n");
+		return PTR_ERR(clk);
+	}
+
+	ret = clk_prepare_enable(clk);
+	if (ret)
+		return ret;
+
+	timer_clk = clk_get_rate(clk);
+
+	return armada_370_xp_timer_common_init(np);
+}
+TIMER_OF_DECLARE(armada_xp, "marvell,armada-xp-timer",
+		       armada_xp_timer_init);
+
+static int __init armada_375_timer_init(struct device_node *np)
+{
+	struct clk *clk;
+	int ret;
+
+	clk = of_clk_get_by_name(np, "fixed");
+	if (!IS_ERR(clk)) {
+		ret = clk_prepare_enable(clk);
+		if (ret)
+			return ret;
+		timer_clk = clk_get_rate(clk);
+	} else {
+
+		/*
+		 * This fallback is required in order to retain proper
+		 * devicetree backwards compatibility.
+		 */
+		clk = of_clk_get(np, 0);
+
+		/* Must have at least a clock */
+		if (IS_ERR(clk)) {
+			pr_err("Failed to get clock\n");
+			return PTR_ERR(clk);
+		}
+
+		ret = clk_prepare_enable(clk);
+		if (ret)
+			return ret;
+
+		timer_clk = clk_get_rate(clk) / TIMER_DIVIDER;
+		timer25Mhz = false;
+	}
+
+	return armada_370_xp_timer_common_init(np);
+}
+TIMER_OF_DECLARE(armada_375, "marvell,armada-375-timer",
+		       armada_375_timer_init);
+
+static int __init armada_370_timer_init(struct device_node *np)
+{
+	struct clk *clk;
+	int ret;
+
+	clk = of_clk_get(np, 0);
+	if (IS_ERR(clk)) {
+		pr_err("Failed to get clock\n");
+		return PTR_ERR(clk);
+	}
+
+	ret = clk_prepare_enable(clk);
+	if (ret)
+		return ret;
+
+	timer_clk = clk_get_rate(clk) / TIMER_DIVIDER;
+	timer25Mhz = false;
+
+	return armada_370_xp_timer_common_init(np);
+}
+TIMER_OF_DECLARE(armada_370, "marvell,armada-370-timer",
+		       armada_370_timer_init);

drivers/clocksource/time-efm32.c

@@ -0,0 +1,287 @@
+/*
+ * Copyright (C) 2013 Pengutronix
+ * Uwe Kleine-Koenig <u.kleine-koenig@pengutronix.de>
+ *
+ * This program is free software; you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License version 2 as published by the
+ * Free Software Foundation.
+ */
+
+#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
+
+#include <linux/kernel.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/clk.h>
+
+#define TIMERn_CTRL			0x00
+#define TIMERn_CTRL_PRESC(val)			(((val) & 0xf) << 24)
+#define TIMERn_CTRL_PRESC_1024			TIMERn_CTRL_PRESC(10)
+#define TIMERn_CTRL_CLKSEL(val)			(((val) & 0x3) << 16)
+#define TIMERn_CTRL_CLKSEL_PRESCHFPERCLK	TIMERn_CTRL_CLKSEL(0)
+#define TIMERn_CTRL_OSMEN			0x00000010
+#define TIMERn_CTRL_MODE(val)			(((val) & 0x3) <<  0)
+#define TIMERn_CTRL_MODE_UP			TIMERn_CTRL_MODE(0)
+#define TIMERn_CTRL_MODE_DOWN			TIMERn_CTRL_MODE(1)
+
+#define TIMERn_CMD			0x04
+#define TIMERn_CMD_START			0x00000001
+#define TIMERn_CMD_STOP				0x00000002
+
+#define TIMERn_IEN			0x0c
+#define TIMERn_IF			0x10
+#define TIMERn_IFS			0x14
+#define TIMERn_IFC			0x18
+#define TIMERn_IRQ_UF				0x00000002
+
+#define TIMERn_TOP			0x1c
+#define TIMERn_CNT			0x24
+
+struct efm32_clock_event_ddata {
+	struct clock_event_device evtdev;
+	void __iomem *base;
+	unsigned periodic_top;
+};
+
+static int efm32_clock_event_shutdown(struct clock_event_device *evtdev)
+{
+	struct efm32_clock_event_ddata *ddata =
+		container_of(evtdev, struct efm32_clock_event_ddata, evtdev);
+
+	writel_relaxed(TIMERn_CMD_STOP, ddata->base + TIMERn_CMD);
+	return 0;
+}
+
+static int efm32_clock_event_set_oneshot(struct clock_event_device *evtdev)
+{
+	struct efm32_clock_event_ddata *ddata =
+		container_of(evtdev, struct efm32_clock_event_ddata, evtdev);
+
+	writel_relaxed(TIMERn_CMD_STOP, ddata->base + TIMERn_CMD);
+	writel_relaxed(TIMERn_CTRL_PRESC_1024 |
+		       TIMERn_CTRL_CLKSEL_PRESCHFPERCLK |
+		       TIMERn_CTRL_OSMEN |
+		       TIMERn_CTRL_MODE_DOWN,
+		       ddata->base + TIMERn_CTRL);
+	return 0;
+}
+
+static int efm32_clock_event_set_periodic(struct clock_event_device *evtdev)
+{
+	struct efm32_clock_event_ddata *ddata =
+		container_of(evtdev, struct efm32_clock_event_ddata, evtdev);
+
+	writel_relaxed(TIMERn_CMD_STOP, ddata->base + TIMERn_CMD);
+	writel_relaxed(ddata->periodic_top, ddata->base + TIMERn_TOP);
+	writel_relaxed(TIMERn_CTRL_PRESC_1024 |
+		       TIMERn_CTRL_CLKSEL_PRESCHFPERCLK |
+		       TIMERn_CTRL_MODE_DOWN,
+		       ddata->base + TIMERn_CTRL);
+	writel_relaxed(TIMERn_CMD_START, ddata->base + TIMERn_CMD);
+	return 0;
+}
+
+static int efm32_clock_event_set_next_event(unsigned long evt,
+					    struct clock_event_device *evtdev)
+{
+	struct efm32_clock_event_ddata *ddata =
+		container_of(evtdev, struct efm32_clock_event_ddata, evtdev);
+
+	writel_relaxed(TIMERn_CMD_STOP, ddata->base + TIMERn_CMD);
+	writel_relaxed(evt, ddata->base + TIMERn_CNT);
+	writel_relaxed(TIMERn_CMD_START, ddata->base + TIMERn_CMD);
+
+	return 0;
+}
+
+static irqreturn_t efm32_clock_event_handler(int irq, void *dev_id)
+{
+	struct efm32_clock_event_ddata *ddata = dev_id;
+
+	writel_relaxed(TIMERn_IRQ_UF, ddata->base + TIMERn_IFC);
+
+	ddata->evtdev.event_handler(&ddata->evtdev);
+
+	return IRQ_HANDLED;
+}
+
+static struct efm32_clock_event_ddata clock_event_ddata = {
+	.evtdev = {
+		.name = "efm32 clockevent",
+		.features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_PERIODIC,
+		.set_state_shutdown = efm32_clock_event_shutdown,
+		.set_state_periodic = efm32_clock_event_set_periodic,
+		.set_state_oneshot = efm32_clock_event_set_oneshot,
+		.set_next_event = efm32_clock_event_set_next_event,
+		.rating = 200,
+	},
+};
+
+static struct irqaction efm32_clock_event_irq = {
+	.name = "efm32 clockevent",
+	.flags = IRQF_TIMER,
+	.handler = efm32_clock_event_handler,
+	.dev_id = &clock_event_ddata,
+};
+
+static int __init efm32_clocksource_init(struct device_node *np)
+{
+	struct clk *clk;
+	void __iomem *base;
+	unsigned long rate;
+	int ret;
+
+	clk = of_clk_get(np, 0);
+	if (IS_ERR(clk)) {
+		ret = PTR_ERR(clk);
+		pr_err("failed to get clock for clocksource (%d)\n", ret);
+		goto err_clk_get;
+	}
+
+	ret = clk_prepare_enable(clk);
+	if (ret) {
+		pr_err("failed to enable timer clock for clocksource (%d)\n",
+		       ret);
+		goto err_clk_enable;
+	}
+	rate = clk_get_rate(clk);
+
+	base = of_iomap(np, 0);
+	if (!base) {
+		ret = -EADDRNOTAVAIL;
+		pr_err("failed to map registers for clocksource\n");
+		goto err_iomap;
+	}
+
+	writel_relaxed(TIMERn_CTRL_PRESC_1024 |
+		       TIMERn_CTRL_CLKSEL_PRESCHFPERCLK |
+		       TIMERn_CTRL_MODE_UP, base + TIMERn_CTRL);
+	writel_relaxed(TIMERn_CMD_START, base + TIMERn_CMD);
+
+	ret = clocksource_mmio_init(base + TIMERn_CNT, "efm32 timer",
+				    DIV_ROUND_CLOSEST(rate, 1024), 200, 16,
+				    clocksource_mmio_readl_up);
+	if (ret) {
+		pr_err("failed to init clocksource (%d)\n", ret);
+		goto err_clocksource_init;
+	}
+
+	return 0;
+
+err_clocksource_init:
+
+	iounmap(base);
+err_iomap:
+
+	clk_disable_unprepare(clk);
+err_clk_enable:
+
+	clk_put(clk);
+err_clk_get:
+
+	return ret;
+}
+
+static int __init efm32_clockevent_init(struct device_node *np)
+{
+	struct clk *clk;
+	void __iomem *base;
+	unsigned long rate;
+	int irq;
+	int ret;
+
+	clk = of_clk_get(np, 0);
+	if (IS_ERR(clk)) {
+		ret = PTR_ERR(clk);
+		pr_err("failed to get clock for clockevent (%d)\n", ret);
+		goto err_clk_get;
+	}
+
+	ret = clk_prepare_enable(clk);
+	if (ret) {
+		pr_err("failed to enable timer clock for clockevent (%d)\n",
+		       ret);
+		goto err_clk_enable;
+	}
+	rate = clk_get_rate(clk);
+
+	base = of_iomap(np, 0);
+	if (!base) {
+		ret = -EADDRNOTAVAIL;
+		pr_err("failed to map registers for clockevent\n");
+		goto err_iomap;
+	}
+
+	irq = irq_of_parse_and_map(np, 0);
+	if (!irq) {
+		ret = -ENOENT;
+		pr_err("failed to get irq for clockevent\n");
+		goto err_get_irq;
+	}
+
+	writel_relaxed(TIMERn_IRQ_UF, base + TIMERn_IEN);
+
+	clock_event_ddata.base = base;
+	clock_event_ddata.periodic_top = DIV_ROUND_CLOSEST(rate, 1024 * HZ);
+
+	clockevents_config_and_register(&clock_event_ddata.evtdev,
+					DIV_ROUND_CLOSEST(rate, 1024),
+					0xf, 0xffff);
+
+	ret = setup_irq(irq, &efm32_clock_event_irq);
+	if (ret) {
+		pr_err("Failed setup irq\n");
+		goto err_setup_irq;
+	}
+
+	return 0;
+
+err_setup_irq:
+err_get_irq:
+
+	iounmap(base);
+err_iomap:
+
+	clk_disable_unprepare(clk);
+err_clk_enable:
+
+	clk_put(clk);
+err_clk_get:
+
+	return ret;
+}
+
+/*
+ * This function asserts that we have exactly one clocksource and one
+ * clock_event_device in the end.
+ */
+static int __init efm32_timer_init(struct device_node *np)
+{
+	static int has_clocksource, has_clockevent;
+	int ret = 0;
+
+	if (!has_clocksource) {
+		ret = efm32_clocksource_init(np);
+		if (!ret) {
+			has_clocksource = 1;
+			return 0;
+		}
+	}
+
+	if (!has_clockevent) {
+		ret = efm32_clockevent_init(np);
+		if (!ret) {
+			has_clockevent = 1;
+			return 0;
+		}
+	}
+
+	return ret;
+}
+TIMER_OF_DECLARE(efm32compat, "efm32,timer", efm32_timer_init);
+TIMER_OF_DECLARE(efm32, "energymicro,efm32-timer", efm32_timer_init);

drivers/clocksource/time-lpc32xx.c

@@ -0,0 +1,314 @@
+/*
+ * Clocksource driver for NXP LPC32xx/18xx/43xx timer
+ *
+ * Copyright (C) 2015 Joachim Eastwood <manabian@gmail.com>
+ *
+ * Based on:
+ * time-efm32 Copyright (C) 2013 Pengutronix
+ * mach-lpc32xx/timer.c Copyright (C) 2009 - 2010 NXP Semiconductors
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2. This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ *
+ */
+
+#define pr_fmt(fmt) "%s: " fmt, __func__
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+
+#define LPC32XX_TIMER_IR		0x000
+#define  LPC32XX_TIMER_IR_MR0INT	BIT(0)
+#define LPC32XX_TIMER_TCR		0x004
+#define  LPC32XX_TIMER_TCR_CEN		BIT(0)
+#define  LPC32XX_TIMER_TCR_CRST		BIT(1)
+#define LPC32XX_TIMER_TC		0x008
+#define LPC32XX_TIMER_PR		0x00c
+#define LPC32XX_TIMER_MCR		0x014
+#define  LPC32XX_TIMER_MCR_MR0I		BIT(0)
+#define  LPC32XX_TIMER_MCR_MR0R		BIT(1)
+#define  LPC32XX_TIMER_MCR_MR0S		BIT(2)
+#define LPC32XX_TIMER_MR0		0x018
+#define LPC32XX_TIMER_CTCR		0x070
+
+struct lpc32xx_clock_event_ddata {
+	struct clock_event_device evtdev;
+	void __iomem *base;
+	u32 ticks_per_jiffy;
+};
+
+/* Needed for the sched clock */
+static void __iomem *clocksource_timer_counter;
+
+static u64 notrace lpc32xx_read_sched_clock(void)
+{
+	return readl(clocksource_timer_counter);
+}
+
+static unsigned long lpc32xx_delay_timer_read(void)
+{
+	return readl(clocksource_timer_counter);
+}
+
+static struct delay_timer lpc32xx_delay_timer = {
+	.read_current_timer = lpc32xx_delay_timer_read,
+};
+
+static int lpc32xx_clkevt_next_event(unsigned long delta,
+				     struct clock_event_device *evtdev)
+{
+	struct lpc32xx_clock_event_ddata *ddata =
+		container_of(evtdev, struct lpc32xx_clock_event_ddata, evtdev);
+
+	/*
+	 * Place timer in reset and program the delta in the match
+	 * channel 0 (MR0). When the timer counter matches the value
+	 * in MR0 register the match will trigger an interrupt.
+	 * After setup the timer is released from reset and enabled.
+	 */
+	writel_relaxed(LPC32XX_TIMER_TCR_CRST, ddata->base + LPC32XX_TIMER_TCR);
+	writel_relaxed(delta, ddata->base + LPC32XX_TIMER_MR0);
+	writel_relaxed(LPC32XX_TIMER_TCR_CEN, ddata->base + LPC32XX_TIMER_TCR);
+
+	return 0;
+}
+
+static int lpc32xx_clkevt_shutdown(struct clock_event_device *evtdev)
+{
+	struct lpc32xx_clock_event_ddata *ddata =
+		container_of(evtdev, struct lpc32xx_clock_event_ddata, evtdev);
+
+	/* Disable the timer */
+	writel_relaxed(0, ddata->base + LPC32XX_TIMER_TCR);
+
+	return 0;
+}
+
+static int lpc32xx_clkevt_oneshot(struct clock_event_device *evtdev)
+{
+	struct lpc32xx_clock_event_ddata *ddata =
+		container_of(evtdev, struct lpc32xx_clock_event_ddata, evtdev);
+
+	/*
+	 * When using oneshot, we must also disable the timer
+	 * to wait for the first call to set_next_event().
+	 */
+	writel_relaxed(0, ddata->base + LPC32XX_TIMER_TCR);
+
+	/* Enable interrupt, reset on match and stop on match (MCR). */
+	writel_relaxed(LPC32XX_TIMER_MCR_MR0I | LPC32XX_TIMER_MCR_MR0R |
+		       LPC32XX_TIMER_MCR_MR0S, ddata->base + LPC32XX_TIMER_MCR);
+	return 0;
+}
+
+static int lpc32xx_clkevt_periodic(struct clock_event_device *evtdev)
+{
+	struct lpc32xx_clock_event_ddata *ddata =
+		container_of(evtdev, struct lpc32xx_clock_event_ddata, evtdev);
+
+	/* Enable interrupt and reset on match. */
+	writel_relaxed(LPC32XX_TIMER_MCR_MR0I | LPC32XX_TIMER_MCR_MR0R,
+		       ddata->base + LPC32XX_TIMER_MCR);
+
+	/*
+	 * Place timer in reset and program the delta in the match
+	 * channel 0 (MR0).
+	 */
+	writel_relaxed(LPC32XX_TIMER_TCR_CRST, ddata->base + LPC32XX_TIMER_TCR);
+	writel_relaxed(ddata->ticks_per_jiffy, ddata->base + LPC32XX_TIMER_MR0);
+	writel_relaxed(LPC32XX_TIMER_TCR_CEN, ddata->base + LPC32XX_TIMER_TCR);
+
+	return 0;
+}
+
+static irqreturn_t lpc32xx_clock_event_handler(int irq, void *dev_id)
+{
+	struct lpc32xx_clock_event_ddata *ddata = dev_id;
+
+	/* Clear match on channel 0 */
+	writel_relaxed(LPC32XX_TIMER_IR_MR0INT, ddata->base + LPC32XX_TIMER_IR);
+
+	ddata->evtdev.event_handler(&ddata->evtdev);
+
+	return IRQ_HANDLED;
+}
+
+static struct lpc32xx_clock_event_ddata lpc32xx_clk_event_ddata = {
+	.evtdev = {
+		.name			= "lpc3220 clockevent",
+		.features		= CLOCK_EVT_FEAT_ONESHOT |
+					  CLOCK_EVT_FEAT_PERIODIC,
+		.rating			= 300,
+		.set_next_event		= lpc32xx_clkevt_next_event,
+		.set_state_shutdown	= lpc32xx_clkevt_shutdown,
+		.set_state_oneshot	= lpc32xx_clkevt_oneshot,
+		.set_state_periodic	= lpc32xx_clkevt_periodic,
+	},
+};
+
+static int __init lpc32xx_clocksource_init(struct device_node *np)
+{
+	void __iomem *base;
+	unsigned long rate;
+	struct clk *clk;
+	int ret;
+
+	clk = of_clk_get_by_name(np, "timerclk");
+	if (IS_ERR(clk)) {
+		pr_err("clock get failed (%ld)\n", PTR_ERR(clk));
+		return PTR_ERR(clk);
+	}
+
+	ret = clk_prepare_enable(clk);
+	if (ret) {
+		pr_err("clock enable failed (%d)\n", ret);
+		goto err_clk_enable;
+	}
+
+	base = of_iomap(np, 0);
+	if (!base) {
+		pr_err("unable to map registers\n");
+		ret = -EADDRNOTAVAIL;
+		goto err_iomap;
+	}
+
+	/*
+	 * Disable and reset timer then set it to free running timer
+	 * mode (CTCR) with no prescaler (PR) or match operations (MCR).
+	 * After setup the timer is released from reset and enabled.
+	 */
+	writel_relaxed(LPC32XX_TIMER_TCR_CRST, base + LPC32XX_TIMER_TCR);
+	writel_relaxed(0, base + LPC32XX_TIMER_PR);
+	writel_relaxed(0, base + LPC32XX_TIMER_MCR);
+	writel_relaxed(0, base + LPC32XX_TIMER_CTCR);
+	writel_relaxed(LPC32XX_TIMER_TCR_CEN, base + LPC32XX_TIMER_TCR);
+
+	rate = clk_get_rate(clk);
+	ret = clocksource_mmio_init(base + LPC32XX_TIMER_TC, "lpc3220 timer",
+				    rate, 300, 32, clocksource_mmio_readl_up);
+	if (ret) {
+		pr_err("failed to init clocksource (%d)\n", ret);
+		goto err_clocksource_init;
+	}
+
+	clocksource_timer_counter = base + LPC32XX_TIMER_TC;
+	lpc32xx_delay_timer.freq = rate;
+	register_current_timer_delay(&lpc32xx_delay_timer);
+	sched_clock_register(lpc32xx_read_sched_clock, 32, rate);
+
+	return 0;
+
+err_clocksource_init:
+	iounmap(base);
+err_iomap:
+	clk_disable_unprepare(clk);
+err_clk_enable:
+	clk_put(clk);
+	return ret;
+}
+
+static int __init lpc32xx_clockevent_init(struct device_node *np)
+{
+	void __iomem *base;
+	unsigned long rate;
+	struct clk *clk;
+	int ret, irq;
+
+	clk = of_clk_get_by_name(np, "timerclk");
+	if (IS_ERR(clk)) {
+		pr_err("clock get failed (%ld)\n", PTR_ERR(clk));
+		return PTR_ERR(clk);
+	}
+
+	ret = clk_prepare_enable(clk);
+	if (ret) {
+		pr_err("clock enable failed (%d)\n", ret);
+		goto err_clk_enable;
+	}
+
+	base = of_iomap(np, 0);
+	if (!base) {
+		pr_err("unable to map registers\n");
+		ret = -EADDRNOTAVAIL;
+		goto err_iomap;
+	}
+
+	irq = irq_of_parse_and_map(np, 0);
+	if (!irq) {
+		pr_err("get irq failed\n");
+		ret = -ENOENT;
+		goto err_irq;
+	}
+
+	/*
+	 * Disable timer and clear any pending interrupt (IR) on match
+	 * channel 0 (MR0). Clear the prescaler as it's not used.
+	 */
+	writel_relaxed(0, base + LPC32XX_TIMER_TCR);
+	writel_relaxed(0, base + LPC32XX_TIMER_PR);
+	writel_relaxed(0, base + LPC32XX_TIMER_CTCR);
+	writel_relaxed(LPC32XX_TIMER_IR_MR0INT, base + LPC32XX_TIMER_IR);
+
+	rate = clk_get_rate(clk);
+	lpc32xx_clk_event_ddata.base = base;
+	lpc32xx_clk_event_ddata.ticks_per_jiffy = DIV_ROUND_CLOSEST(rate, HZ);
+	clockevents_config_and_register(&lpc32xx_clk_event_ddata.evtdev,
+					rate, 1, -1);
+
+	ret = request_irq(irq, lpc32xx_clock_event_handler,
+			  IRQF_TIMER | IRQF_IRQPOLL, "lpc3220 clockevent",
+			  &lpc32xx_clk_event_ddata);
+	if (ret) {
+		pr_err("request irq failed\n");
+		goto err_irq;
+	}
+
+	return 0;
+
+err_irq:
+	iounmap(base);
+err_iomap:
+	clk_disable_unprepare(clk);
+err_clk_enable:
+	clk_put(clk);
+	return ret;
+}
+
+/*
+ * This function asserts that we have exactly one clocksource and one
+ * clock_event_device in the end.
+ */
+static int __init lpc32xx_timer_init(struct device_node *np)
+{
+	static int has_clocksource, has_clockevent;
+	int ret = 0;
+
+	if (!has_clocksource) {
+		ret = lpc32xx_clocksource_init(np);
+		if (!ret) {
+			has_clocksource = 1;
+			return 0;
+		}
+	}
+
+	if (!has_clockevent) {
+		ret = lpc32xx_clockevent_init(np);
+		if (!ret) {
+			has_clockevent = 1;
+			return 0;
+		}
+	}
+
+	return ret;
+}
+TIMER_OF_DECLARE(lpc32xx_timer, "nxp,lpc3220-timer", lpc32xx_timer_init);

drivers/clocksource/time-orion.c

@@ -0,0 +1,192 @@
+/*
+ * Marvell Orion SoC timer handling.
+ *
+ * Sebastian Hesselbarth <sebastian.hesselbarth@gmail.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ *
+ * Timer 0 is used as free-running clocksource, while timer 1 is
+ * used as clock_event_device.
+ */
+
+#include <linux/kernel.h>
+#include <linux/bitops.h>
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/spinlock.h>
+#include <linux/sched_clock.h>
+
+#define TIMER_CTRL		0x00
+#define  TIMER0_EN		BIT(0)
+#define  TIMER0_RELOAD_EN	BIT(1)
+#define  TIMER1_EN		BIT(2)
+#define  TIMER1_RELOAD_EN	BIT(3)
+#define TIMER0_RELOAD		0x10
+#define TIMER0_VAL		0x14
+#define TIMER1_RELOAD		0x18
+#define TIMER1_VAL		0x1c
+
+#define ORION_ONESHOT_MIN	1
+#define ORION_ONESHOT_MAX	0xfffffffe
+
+static void __iomem *timer_base;
+
+static unsigned long notrace orion_read_timer(void)
+{
+	return ~readl(timer_base + TIMER0_VAL);
+}
+
+static struct delay_timer orion_delay_timer = {
+	.read_current_timer = orion_read_timer,
+};
+
+static void orion_delay_timer_init(unsigned long rate)
+{
+	orion_delay_timer.freq = rate;
+	register_current_timer_delay(&orion_delay_timer);
+}
+
+/*
+ * Free-running clocksource handling.
+ */
+static u64 notrace orion_read_sched_clock(void)
+{
+	return ~readl(timer_base + TIMER0_VAL);
+}
+
+/*
+ * Clockevent handling.
+ */
+static u32 ticks_per_jiffy;
+
+static int orion_clkevt_next_event(unsigned long delta,
+				   struct clock_event_device *dev)
+{
+	/* setup and enable one-shot timer */
+	writel(delta, timer_base + TIMER1_VAL);
+	atomic_io_modify(timer_base + TIMER_CTRL,
+		TIMER1_RELOAD_EN | TIMER1_EN, TIMER1_EN);
+
+	return 0;
+}
+
+static int orion_clkevt_shutdown(struct clock_event_device *dev)
+{
+	/* disable timer */
+	atomic_io_modify(timer_base + TIMER_CTRL,
+			 TIMER1_RELOAD_EN | TIMER1_EN, 0);
+	return 0;
+}
+
+static int orion_clkevt_set_periodic(struct clock_event_device *dev)
+{
+	/* setup and enable periodic timer at 1/HZ intervals */
+	writel(ticks_per_jiffy - 1, timer_base + TIMER1_RELOAD);
+	writel(ticks_per_jiffy - 1, timer_base + TIMER1_VAL);
+	atomic_io_modify(timer_base + TIMER_CTRL,
+			 TIMER1_RELOAD_EN | TIMER1_EN,
+			 TIMER1_RELOAD_EN | TIMER1_EN);
+	return 0;
+}
+
+static struct clock_event_device orion_clkevt = {
+	.name			= "orion_event",
+	.features		= CLOCK_EVT_FEAT_ONESHOT |
+				  CLOCK_EVT_FEAT_PERIODIC,
+	.shift			= 32,
+	.rating			= 300,
+	.set_next_event		= orion_clkevt_next_event,
+	.set_state_shutdown	= orion_clkevt_shutdown,
+	.set_state_periodic	= orion_clkevt_set_periodic,
+	.set_state_oneshot	= orion_clkevt_shutdown,
+	.tick_resume		= orion_clkevt_shutdown,
+};
+
+static irqreturn_t orion_clkevt_irq_handler(int irq, void *dev_id)
+{
+	orion_clkevt.event_handler(&orion_clkevt);
+	return IRQ_HANDLED;
+}
+
+static struct irqaction orion_clkevt_irq = {
+	.name		= "orion_event",
+	.flags		= IRQF_TIMER,
+	.handler	= orion_clkevt_irq_handler,
+};
+
+static int __init orion_timer_init(struct device_node *np)
+{
+	unsigned long rate;
+	struct clk *clk;
+	int irq, ret;
+
+	/* timer registers are shared with watchdog timer */
+	timer_base = of_iomap(np, 0);
+	if (!timer_base) {
+		pr_err("%s: unable to map resource\n", np->name);
+		return -ENXIO;
+	}
+
+	clk = of_clk_get(np, 0);
+	if (IS_ERR(clk)) {
+		pr_err("%s: unable to get clk\n", np->name);
+		return PTR_ERR(clk);
+	}
+
+	ret = clk_prepare_enable(clk);
+	if (ret) {
+		pr_err("Failed to prepare clock\n");
+		return ret;
+	}
+
+	/* we are only interested in timer1 irq */
+	irq = irq_of_parse_and_map(np, 1);
+	if (irq <= 0) {
+		pr_err("%s: unable to parse timer1 irq\n", np->name);
+		return -EINVAL;
+	}
+
+	rate = clk_get_rate(clk);
+
+	/* setup timer0 as free-running clocksource */
+	writel(~0, timer_base + TIMER0_VAL);
+	writel(~0, timer_base + TIMER0_RELOAD);
+	atomic_io_modify(timer_base + TIMER_CTRL,
+		TIMER0_RELOAD_EN | TIMER0_EN,
+		TIMER0_RELOAD_EN | TIMER0_EN);
+
+	ret = clocksource_mmio_init(timer_base + TIMER0_VAL,
+				    "orion_clocksource", rate, 300, 32,
+				    clocksource_mmio_readl_down);
+	if (ret) {
+		pr_err("Failed to initialize mmio timer\n");
+		return ret;
+	}
+
+	sched_clock_register(orion_read_sched_clock, 32, rate);
+
+	/* setup timer1 as clockevent timer */
+	ret = setup_irq(irq, &orion_clkevt_irq);
+	if (ret) {
+		pr_err("%s: unable to setup irq\n", np->name);
+		return ret;
+	}
+
+	ticks_per_jiffy = (clk_get_rate(clk) + HZ/2) / HZ;
+	orion_clkevt.cpumask = cpumask_of(0);
+	orion_clkevt.irq = irq;
+	clockevents_config_and_register(&orion_clkevt, rate,
+					ORION_ONESHOT_MIN, ORION_ONESHOT_MAX);
+
+
+	orion_delay_timer_init(rate);
+
+	return 0;
+}
+TIMER_OF_DECLARE(orion_timer, "marvell,orion-timer", orion_timer_init);

drivers/clocksource/time-pistachio.c

@@ -0,0 +1,218 @@
+/*
+ * Pistachio clocksource based on general-purpose timers
+ *
+ * Copyright (C) 2015 Imagination Technologies
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#define pr_fmt(fmt) "%s: " fmt, __func__
+
+#include <linux/clk.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/spinlock.h>
+#include <linux/mfd/syscon.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/sched_clock.h>
+#include <linux/time.h>
+
+/* Top level reg */
+#define CR_TIMER_CTRL_CFG		0x00
+#define TIMER_ME_GLOBAL			BIT(0)
+#define CR_TIMER_REV			0x10
+
+/* Timer specific registers */
+#define TIMER_CFG			0x20
+#define TIMER_ME_LOCAL			BIT(0)
+#define TIMER_RELOAD_VALUE		0x24
+#define TIMER_CURRENT_VALUE		0x28
+#define TIMER_CURRENT_OVERFLOW_VALUE	0x2C
+#define TIMER_IRQ_STATUS		0x30
+#define TIMER_IRQ_CLEAR			0x34
+#define TIMER_IRQ_MASK			0x38
+
+#define PERIP_TIMER_CONTROL		0x90
+
+/* Timer specific configuration Values */
+#define RELOAD_VALUE			0xffffffff
+
+struct pistachio_clocksource {
+	void __iomem *base;
+	raw_spinlock_t lock;
+	struct clocksource cs;
+};
+
+static struct pistachio_clocksource pcs_gpt;
+
+#define to_pistachio_clocksource(cs)	\
+	container_of(cs, struct pistachio_clocksource, cs)
+
+static inline u32 gpt_readl(void __iomem *base, u32 offset, u32 gpt_id)
+{
+	return readl(base + 0x20 * gpt_id + offset);
+}
+
+static inline void gpt_writel(void __iomem *base, u32 value, u32 offset,
+		u32 gpt_id)
+{
+	writel(value, base + 0x20 * gpt_id + offset);
+}
+
+static u64 notrace
+pistachio_clocksource_read_cycles(struct clocksource *cs)
+{
+	struct pistachio_clocksource *pcs = to_pistachio_clocksource(cs);
+	u32 counter, overflw;
+	unsigned long flags;
+
+	/*
+	 * The counter value is only refreshed after the overflow value is read.
+	 * And they must be read in strict order, hence raw spin lock added.
+	 */
+
+	raw_spin_lock_irqsave(&pcs->lock, flags);
+	overflw = gpt_readl(pcs->base, TIMER_CURRENT_OVERFLOW_VALUE, 0);
+	counter = gpt_readl(pcs->base, TIMER_CURRENT_VALUE, 0);
+	raw_spin_unlock_irqrestore(&pcs->lock, flags);
+
+	return (u64)~counter;
+}
+
+static u64 notrace pistachio_read_sched_clock(void)
+{
+	return pistachio_clocksource_read_cycles(&pcs_gpt.cs);
+}
+
+static void pistachio_clksrc_set_mode(struct clocksource *cs, int timeridx,
+			int enable)
+{
+	struct pistachio_clocksource *pcs = to_pistachio_clocksource(cs);
+	u32 val;
+
+	val = gpt_readl(pcs->base, TIMER_CFG, timeridx);
+	if (enable)
+		val |= TIMER_ME_LOCAL;
+	else
+		val &= ~TIMER_ME_LOCAL;
+
+	gpt_writel(pcs->base, val, TIMER_CFG, timeridx);
+}
+
+static void pistachio_clksrc_enable(struct clocksource *cs, int timeridx)
+{
+	struct pistachio_clocksource *pcs = to_pistachio_clocksource(cs);
+
+	/* Disable GPT local before loading reload value */
+	pistachio_clksrc_set_mode(cs, timeridx, false);
+	gpt_writel(pcs->base, RELOAD_VALUE, TIMER_RELOAD_VALUE, timeridx);
+	pistachio_clksrc_set_mode(cs, timeridx, true);
+}
+
+static void pistachio_clksrc_disable(struct clocksource *cs, int timeridx)
+{
+	/* Disable GPT local */
+	pistachio_clksrc_set_mode(cs, timeridx, false);
+}
+
+static int pistachio_clocksource_enable(struct clocksource *cs)
+{
+	pistachio_clksrc_enable(cs, 0);
+	return 0;
+}
+
+static void pistachio_clocksource_disable(struct clocksource *cs)
+{
+	pistachio_clksrc_disable(cs, 0);
+}
+
+/* Desirable clock source for pistachio platform */
+static struct pistachio_clocksource pcs_gpt = {
+	.cs =	{
+		.name		= "gptimer",
+		.rating		= 300,
+		.enable		= pistachio_clocksource_enable,
+		.disable	= pistachio_clocksource_disable,
+		.read		= pistachio_clocksource_read_cycles,
+		.mask		= CLOCKSOURCE_MASK(32),
+		.flags		= CLOCK_SOURCE_IS_CONTINUOUS |
+				  CLOCK_SOURCE_SUSPEND_NONSTOP,
+		},
+};
+
+static int __init pistachio_clksrc_of_init(struct device_node *node)
+{
+	struct clk *sys_clk, *fast_clk;
+	struct regmap *periph_regs;
+	unsigned long rate;
+	int ret;
+
+	pcs_gpt.base = of_iomap(node, 0);
+	if (!pcs_gpt.base) {
+		pr_err("cannot iomap\n");
+		return -ENXIO;
+	}
+
+	periph_regs = syscon_regmap_lookup_by_phandle(node, "img,cr-periph");
+	if (IS_ERR(periph_regs)) {
+		pr_err("cannot get peripheral regmap (%ld)\n",
+		       PTR_ERR(periph_regs));
+		return PTR_ERR(periph_regs);
+	}
+
+	/* Switch to using the fast counter clock */
+	ret = regmap_update_bits(periph_regs, PERIP_TIMER_CONTROL,
+				 0xf, 0x0);
+	if (ret)
+		return ret;
+
+	sys_clk = of_clk_get_by_name(node, "sys");
+	if (IS_ERR(sys_clk)) {
+		pr_err("clock get failed (%ld)\n", PTR_ERR(sys_clk));
+		return PTR_ERR(sys_clk);
+	}
+
+	fast_clk = of_clk_get_by_name(node, "fast");
+	if (IS_ERR(fast_clk)) {
+		pr_err("clock get failed (%lu)\n", PTR_ERR(fast_clk));
+		return PTR_ERR(fast_clk);
+	}
+
+	ret = clk_prepare_enable(sys_clk);
+	if (ret < 0) {
+		pr_err("failed to enable clock (%d)\n", ret);
+		return ret;
+	}
+
+	ret = clk_prepare_enable(fast_clk);
+	if (ret < 0) {
+		pr_err("failed to enable clock (%d)\n", ret);
+		clk_disable_unprepare(sys_clk);
+		return ret;
+	}
+
+	rate = clk_get_rate(fast_clk);
+
+	/* Disable irq's for clocksource usage */
+	gpt_writel(pcs_gpt.base, 0, TIMER_IRQ_MASK, 0);
+	gpt_writel(pcs_gpt.base, 0, TIMER_IRQ_MASK, 1);
+	gpt_writel(pcs_gpt.base, 0, TIMER_IRQ_MASK, 2);
+	gpt_writel(pcs_gpt.base, 0, TIMER_IRQ_MASK, 3);
+
+	/* Enable timer block */
+	writel(TIMER_ME_GLOBAL, pcs_gpt.base);
+
+	raw_spin_lock_init(&pcs_gpt.lock);
+	sched_clock_register(pistachio_read_sched_clock, 32, rate);
+	return clocksource_register_hz(&pcs_gpt.cs, rate);
+}
+TIMER_OF_DECLARE(pistachio_gptimer, "img,pistachio-gptimer",
+		       pistachio_clksrc_of_init);

drivers/clocksource/timer-atcpit100.c

@@ -0,0 +1,266 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+/*
+ *  Andestech ATCPIT100 Timer Device Driver Implementation
+ * Rick Chen, Andes Technology Corporation <rick@andestech.com>
+ *
+ */
+
+#include <linux/irq.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/cpufreq.h>
+#include <linux/sched.h>
+#include <linux/sched_clock.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/of_platform.h>
+#include "timer-of.h"
+#ifdef CONFIG_NDS32
+#include <asm/vdso_timer_info.h>
+#endif
+
+/*
+ * Definition of register offsets
+ */
+
+/* ID and Revision Register */
+#define ID_REV		0x0
+
+/* Configuration Register */
+#define CFG		0x10
+
+/* Interrupt Enable Register */
+#define INT_EN		0x14
+#define CH_INT_EN(c, i)	((1<<i)<<(4*c))
+#define CH0INT0EN	0x01
+
+/* Interrupt Status Register */
+#define INT_STA		0x18
+#define CH0INT0		0x01
+
+/* Channel Enable Register */
+#define CH_EN		0x1C
+#define CH0TMR0EN	0x1
+#define CH1TMR0EN	0x10
+
+/* Channel 0 , 1 Control Register */
+#define CH0_CTL		(0x20)
+#define CH1_CTL		(0x20 + 0x10)
+
+/* Channel clock source , bit 3 , 0:External clock , 1:APB clock */
+#define APB_CLK		BIT(3)
+
+/* Channel mode , bit 0~2 */
+#define TMR_32		0x1
+#define TMR_16		0x2
+#define TMR_8		0x3
+
+/* Channel 0 , 1 Reload Register */
+#define CH0_REL		(0x24)
+#define CH1_REL		(0x24 + 0x10)
+
+/* Channel 0 , 1 Counter Register */
+#define CH0_CNT		(0x28)
+#define CH1_CNT		(0x28 + 0x10)
+
+#define TIMER_SYNC_TICKS	3
+
+static void atcpit100_ch1_tmr0_en(void __iomem *base)
+{
+	writel(~0, base + CH1_REL);
+	writel(APB_CLK|TMR_32, base + CH1_CTL);
+}
+
+static void atcpit100_ch0_tmr0_en(void __iomem *base)
+{
+	writel(APB_CLK|TMR_32, base + CH0_CTL);
+}
+
+static void atcpit100_clkevt_time_setup(void __iomem *base, unsigned long delay)
+{
+	writel(delay, base + CH0_CNT);
+	writel(delay, base + CH0_REL);
+}
+
+static void atcpit100_timer_clear_interrupt(void __iomem *base)
+{
+	u32 val;
+
+	val = readl(base + INT_STA);
+	writel(val | CH0INT0, base + INT_STA);
+}
+
+static void atcpit100_clocksource_start(void __iomem *base)
+{
+	u32 val;
+
+	val = readl(base + CH_EN);
+	writel(val | CH1TMR0EN, base + CH_EN);
+}
+
+static void atcpit100_clkevt_time_start(void __iomem *base)
+{
+	u32 val;
+
+	val = readl(base + CH_EN);
+	writel(val | CH0TMR0EN, base + CH_EN);
+}
+
+static void atcpit100_clkevt_time_stop(void __iomem *base)
+{
+	u32 val;
+
+	atcpit100_timer_clear_interrupt(base);
+	val = readl(base + CH_EN);
+	writel(val & ~CH0TMR0EN, base + CH_EN);
+}
+
+static int atcpit100_clkevt_next_event(unsigned long evt,
+	struct clock_event_device *clkevt)
+{
+	u32 val;
+	struct timer_of *to = to_timer_of(clkevt);
+
+	val = readl(timer_of_base(to) + CH_EN);
+	writel(val & ~CH0TMR0EN, timer_of_base(to) + CH_EN);
+	writel(evt, timer_of_base(to) + CH0_REL);
+	writel(val | CH0TMR0EN, timer_of_base(to) + CH_EN);
+
+	return 0;
+}
+
+static int atcpit100_clkevt_set_periodic(struct clock_event_device *evt)
+{
+	struct timer_of *to = to_timer_of(evt);
+
+	atcpit100_clkevt_time_setup(timer_of_base(to), timer_of_period(to));
+	atcpit100_clkevt_time_start(timer_of_base(to));
+
+	return 0;
+}
+static int atcpit100_clkevt_shutdown(struct clock_event_device *evt)
+{
+	struct timer_of *to = to_timer_of(evt);
+
+	atcpit100_clkevt_time_stop(timer_of_base(to));
+
+	return 0;
+}
+static int atcpit100_clkevt_set_oneshot(struct clock_event_device *evt)
+{
+	struct timer_of *to = to_timer_of(evt);
+	u32 val;
+
+	writel(~0x0, timer_of_base(to) + CH0_REL);
+	val = readl(timer_of_base(to) + CH_EN);
+	writel(val | CH0TMR0EN, timer_of_base(to) + CH_EN);
+
+	return 0;
+}
+
+static irqreturn_t atcpit100_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = (struct clock_event_device *)dev_id;
+	struct timer_of *to = to_timer_of(evt);
+
+	atcpit100_timer_clear_interrupt(timer_of_base(to));
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static struct timer_of to = {
+	.flags = TIMER_OF_IRQ | TIMER_OF_CLOCK | TIMER_OF_BASE,
+
+	.clkevt = {
+		.name = "atcpit100_tick",
+		.rating = 300,
+		.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+		.set_state_shutdown = atcpit100_clkevt_shutdown,
+		.set_state_periodic = atcpit100_clkevt_set_periodic,
+		.set_state_oneshot = atcpit100_clkevt_set_oneshot,
+		.tick_resume = atcpit100_clkevt_shutdown,
+		.set_next_event = atcpit100_clkevt_next_event,
+		.cpumask = cpu_possible_mask,
+	},
+
+	.of_irq = {
+		.handler = atcpit100_timer_interrupt,
+		.flags = IRQF_TIMER | IRQF_IRQPOLL,
+	},
+
+	/*
+	 * FIXME: we currently only support clocking using PCLK
+	 * and using EXTCLK is not supported in the driver.
+	 */
+	.of_clk = {
+		.name = "PCLK",
+	}
+};
+
+static u64 notrace atcpit100_timer_sched_read(void)
+{
+	return ~readl(timer_of_base(&to) + CH1_CNT);
+}
+
+#ifdef CONFIG_NDS32
+static void fill_vdso_need_info(struct device_node *node)
+{
+	struct resource timer_res;
+	of_address_to_resource(node, 0, &timer_res);
+	timer_info.mapping_base = (unsigned long)timer_res.start;
+	timer_info.cycle_count_down = true;
+	timer_info.cycle_count_reg_offset = CH1_CNT;
+}
+#endif
+
+static int __init atcpit100_timer_init(struct device_node *node)
+{
+	int ret;
+	u32 val;
+	void __iomem *base;
+
+	ret = timer_of_init(node, &to);
+	if (ret)
+		return ret;
+
+	base = timer_of_base(&to);
+
+	sched_clock_register(atcpit100_timer_sched_read, 32,
+		timer_of_rate(&to));
+
+	ret = clocksource_mmio_init(base + CH1_CNT,
+		node->name, timer_of_rate(&to), 300, 32,
+		clocksource_mmio_readl_down);
+
+	if (ret) {
+		pr_err("Failed to register clocksource\n");
+		return ret;
+	}
+
+	/* clear channel 0 timer0 interrupt */
+	atcpit100_timer_clear_interrupt(base);
+
+	clockevents_config_and_register(&to.clkevt, timer_of_rate(&to),
+					TIMER_SYNC_TICKS, 0xffffffff);
+	atcpit100_ch0_tmr0_en(base);
+	atcpit100_ch1_tmr0_en(base);
+	atcpit100_clocksource_start(base);
+	atcpit100_clkevt_time_start(base);
+
+	/* Enable channel 0 timer0 interrupt */
+	val = readl(base + INT_EN);
+	writel(val | CH0INT0EN, base + INT_EN);
+
+#ifdef CONFIG_NDS32
+	fill_vdso_need_info(node);
+#endif
+
+	return ret;
+}
+
+TIMER_OF_DECLARE(atcpit100, "andestech,atcpit100", atcpit100_timer_init);

drivers/clocksource/timer-atlas7.c

@@ -0,0 +1,286 @@
+/*
+ * System timer for CSR SiRFprimaII
+ *
+ * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
+ *
+ * Licensed under GPLv2 or later.
+ */
+
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/cpu.h>
+#include <linux/bitops.h>
+#include <linux/irq.h>
+#include <linux/clk.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/sched_clock.h>
+
+#define SIRFSOC_TIMER_32COUNTER_0_CTRL			0x0000
+#define SIRFSOC_TIMER_32COUNTER_1_CTRL			0x0004
+#define SIRFSOC_TIMER_MATCH_0				0x0018
+#define SIRFSOC_TIMER_MATCH_1				0x001c
+#define SIRFSOC_TIMER_COUNTER_0				0x0048
+#define SIRFSOC_TIMER_COUNTER_1				0x004c
+#define SIRFSOC_TIMER_INTR_STATUS			0x0060
+#define SIRFSOC_TIMER_WATCHDOG_EN			0x0064
+#define SIRFSOC_TIMER_64COUNTER_CTRL			0x0068
+#define SIRFSOC_TIMER_64COUNTER_LO			0x006c
+#define SIRFSOC_TIMER_64COUNTER_HI			0x0070
+#define SIRFSOC_TIMER_64COUNTER_LOAD_LO			0x0074
+#define SIRFSOC_TIMER_64COUNTER_LOAD_HI			0x0078
+#define SIRFSOC_TIMER_64COUNTER_RLATCHED_LO		0x007c
+#define SIRFSOC_TIMER_64COUNTER_RLATCHED_HI		0x0080
+
+#define SIRFSOC_TIMER_REG_CNT 6
+
+static unsigned long atlas7_timer_rate;
+
+static const u32 sirfsoc_timer_reg_list[SIRFSOC_TIMER_REG_CNT] = {
+	SIRFSOC_TIMER_WATCHDOG_EN,
+	SIRFSOC_TIMER_32COUNTER_0_CTRL,
+	SIRFSOC_TIMER_32COUNTER_1_CTRL,
+	SIRFSOC_TIMER_64COUNTER_CTRL,
+	SIRFSOC_TIMER_64COUNTER_RLATCHED_LO,
+	SIRFSOC_TIMER_64COUNTER_RLATCHED_HI,
+};
+
+static u32 sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT];
+
+static void __iomem *sirfsoc_timer_base;
+
+/* disable count and interrupt */
+static inline void sirfsoc_timer_count_disable(int idx)
+{
+	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx) & ~0x7,
+		sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx);
+}
+
+/* enable count and interrupt */
+static inline void sirfsoc_timer_count_enable(int idx)
+{
+	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx) | 0x3,
+		sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL + 4 * idx);
+}
+
+/* timer interrupt handler */
+static irqreturn_t sirfsoc_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *ce = dev_id;
+	int cpu = smp_processor_id();
+
+	/* clear timer interrupt */
+	writel_relaxed(BIT(cpu), sirfsoc_timer_base + SIRFSOC_TIMER_INTR_STATUS);
+
+	if (clockevent_state_oneshot(ce))
+		sirfsoc_timer_count_disable(cpu);
+
+	ce->event_handler(ce);
+
+	return IRQ_HANDLED;
+}
+
+/* read 64-bit timer counter */
+static u64 sirfsoc_timer_read(struct clocksource *cs)
+{
+	u64 cycles;
+
+	writel_relaxed((readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL) |
+			BIT(0)) & ~BIT(1), sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);
+
+	cycles = readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_RLATCHED_HI);
+	cycles = (cycles << 32) | readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_RLATCHED_LO);
+
+	return cycles;
+}
+
+static int sirfsoc_timer_set_next_event(unsigned long delta,
+	struct clock_event_device *ce)
+{
+	int cpu = smp_processor_id();
+
+	/* disable timer first, then modify the related registers */
+	sirfsoc_timer_count_disable(cpu);
+
+	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_0 +
+		4 * cpu);
+	writel_relaxed(delta, sirfsoc_timer_base + SIRFSOC_TIMER_MATCH_0 +
+		4 * cpu);
+
+	/* enable the tick */
+	sirfsoc_timer_count_enable(cpu);
+
+	return 0;
+}
+
+/* Oneshot is enabled in set_next_event */
+static int sirfsoc_timer_shutdown(struct clock_event_device *evt)
+{
+	sirfsoc_timer_count_disable(smp_processor_id());
+	return 0;
+}
+
+static void sirfsoc_clocksource_suspend(struct clocksource *cs)
+{
+	int i;
+
+	for (i = 0; i < SIRFSOC_TIMER_REG_CNT; i++)
+		sirfsoc_timer_reg_val[i] = readl_relaxed(sirfsoc_timer_base + sirfsoc_timer_reg_list[i]);
+}
+
+static void sirfsoc_clocksource_resume(struct clocksource *cs)
+{
+	int i;
+
+	for (i = 0; i < SIRFSOC_TIMER_REG_CNT - 2; i++)
+		writel_relaxed(sirfsoc_timer_reg_val[i], sirfsoc_timer_base + sirfsoc_timer_reg_list[i]);
+
+	writel_relaxed(sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT - 2],
+		sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_LO);
+	writel_relaxed(sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT - 1],
+		sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_HI);
+
+	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL) |
+		BIT(1) | BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);
+}
+
+static struct clock_event_device __percpu *sirfsoc_clockevent;
+
+static struct clocksource sirfsoc_clocksource = {
+	.name = "sirfsoc_clocksource",
+	.rating = 200,
+	.mask = CLOCKSOURCE_MASK(64),
+	.flags = CLOCK_SOURCE_IS_CONTINUOUS,
+	.read = sirfsoc_timer_read,
+	.suspend = sirfsoc_clocksource_suspend,
+	.resume = sirfsoc_clocksource_resume,
+};
+
+static struct irqaction sirfsoc_timer_irq = {
+	.name = "sirfsoc_timer0",
+	.flags = IRQF_TIMER | IRQF_NOBALANCING,
+	.handler = sirfsoc_timer_interrupt,
+};
+
+static struct irqaction sirfsoc_timer1_irq = {
+	.name = "sirfsoc_timer1",
+	.flags = IRQF_TIMER | IRQF_NOBALANCING,
+	.handler = sirfsoc_timer_interrupt,
+};
+
+static int sirfsoc_local_timer_starting_cpu(unsigned int cpu)
+{
+	struct clock_event_device *ce = per_cpu_ptr(sirfsoc_clockevent, cpu);
+	struct irqaction *action;
+
+	if (cpu == 0)
+		action = &sirfsoc_timer_irq;
+	else
+		action = &sirfsoc_timer1_irq;
+
+	ce->irq = action->irq;
+	ce->name = "local_timer";
+	ce->features = CLOCK_EVT_FEAT_ONESHOT;
+	ce->rating = 200;
+	ce->set_state_shutdown = sirfsoc_timer_shutdown;
+	ce->set_state_oneshot = sirfsoc_timer_shutdown;
+	ce->tick_resume = sirfsoc_timer_shutdown;
+	ce->set_next_event = sirfsoc_timer_set_next_event;
+	clockevents_calc_mult_shift(ce, atlas7_timer_rate, 60);
+	ce->max_delta_ns = clockevent_delta2ns(-2, ce);
+	ce->max_delta_ticks = (unsigned long)-2;
+	ce->min_delta_ns = clockevent_delta2ns(2, ce);
+	ce->min_delta_ticks = 2;
+	ce->cpumask = cpumask_of(cpu);
+
+	action->dev_id = ce;
+	BUG_ON(setup_irq(ce->irq, action));
+	irq_force_affinity(action->irq, cpumask_of(cpu));
+
+	clockevents_register_device(ce);
+	return 0;
+}
+
+static int sirfsoc_local_timer_dying_cpu(unsigned int cpu)
+{
+	sirfsoc_timer_count_disable(1);
+
+	if (cpu == 0)
+		remove_irq(sirfsoc_timer_irq.irq, &sirfsoc_timer_irq);
+	else
+		remove_irq(sirfsoc_timer1_irq.irq, &sirfsoc_timer1_irq);
+	return 0;
+}
+
+static int __init sirfsoc_clockevent_init(void)
+{
+	sirfsoc_clockevent = alloc_percpu(struct clock_event_device);
+	BUG_ON(!sirfsoc_clockevent);
+
+	/* Install and invoke hotplug callbacks */
+	return cpuhp_setup_state(CPUHP_AP_MARCO_TIMER_STARTING,
+				 "clockevents/marco:starting",
+				 sirfsoc_local_timer_starting_cpu,
+				 sirfsoc_local_timer_dying_cpu);
+}
+
+/* initialize the kernel jiffy timer source */
+static int __init sirfsoc_atlas7_timer_init(struct device_node *np)
+{
+	struct clk *clk;
+
+	clk = of_clk_get(np, 0);
+	BUG_ON(IS_ERR(clk));
+
+	BUG_ON(clk_prepare_enable(clk));
+
+	atlas7_timer_rate = clk_get_rate(clk);
+
+	/* timer dividers: 0, not divided */
+	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);
+	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_0_CTRL);
+	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_32COUNTER_1_CTRL);
+
+	/* Initialize timer counters to 0 */
+	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_LO);
+	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_LOAD_HI);
+	writel_relaxed(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL) |
+		BIT(1) | BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_64COUNTER_CTRL);
+	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_0);
+	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_1);
+
+	/* Clear all interrupts */
+	writel_relaxed(0xFFFF, sirfsoc_timer_base + SIRFSOC_TIMER_INTR_STATUS);
+
+	BUG_ON(clocksource_register_hz(&sirfsoc_clocksource, atlas7_timer_rate));
+
+	return sirfsoc_clockevent_init();
+}
+
+static int __init sirfsoc_of_timer_init(struct device_node *np)
+{
+	sirfsoc_timer_base = of_iomap(np, 0);
+	if (!sirfsoc_timer_base) {
+		pr_err("unable to map timer cpu registers\n");
+		return -ENXIO;
+	}
+
+	sirfsoc_timer_irq.irq = irq_of_parse_and_map(np, 0);
+	if (!sirfsoc_timer_irq.irq) {
+		pr_err("No irq passed for timer0 via DT\n");
+		return -EINVAL;
+	}
+
+	sirfsoc_timer1_irq.irq = irq_of_parse_and_map(np, 1);
+	if (!sirfsoc_timer1_irq.irq) {
+		pr_err("No irq passed for timer1 via DT\n");
+		return -EINVAL;
+	}
+
+	return sirfsoc_atlas7_timer_init(np);
+}
+TIMER_OF_DECLARE(sirfsoc_atlas7_timer, "sirf,atlas7-tick", sirfsoc_of_timer_init);

drivers/clocksource/timer-atmel-pit.c

@@ -0,0 +1,267 @@
+/*
+ * at91sam926x_time.c - Periodic Interval Timer (PIT) for at91sam926x
+ *
+ * Copyright (C) 2005-2006 M. Amine SAYA, ATMEL Rousset, France
+ * Revision	 2005 M. Nicolas Diremdjian, ATMEL Rousset, France
+ * Converted to ClockSource/ClockEvents by David Brownell.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#define pr_fmt(fmt)	"AT91: PIT: " fmt
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/slab.h>
+
+#define AT91_PIT_MR		0x00			/* Mode Register */
+#define AT91_PIT_PITIEN			BIT(25)			/* Timer Interrupt Enable */
+#define AT91_PIT_PITEN			BIT(24)			/* Timer Enabled */
+#define AT91_PIT_PIV			GENMASK(19, 0)		/* Periodic Interval Value */
+
+#define AT91_PIT_SR		0x04			/* Status Register */
+#define AT91_PIT_PITS			BIT(0)			/* Timer Status */
+
+#define AT91_PIT_PIVR		0x08			/* Periodic Interval Value Register */
+#define AT91_PIT_PIIR		0x0c			/* Periodic Interval Image Register */
+#define AT91_PIT_PICNT			GENMASK(31, 20)		/* Interval Counter */
+#define AT91_PIT_CPIV			GENMASK(19, 0)		/* Inverval Value */
+
+#define PIT_CPIV(x)	((x) & AT91_PIT_CPIV)
+#define PIT_PICNT(x)	(((x) & AT91_PIT_PICNT) >> 20)
+
+struct pit_data {
+	struct clock_event_device	clkevt;
+	struct clocksource		clksrc;
+
+	void __iomem	*base;
+	u32		cycle;
+	u32		cnt;
+	unsigned int	irq;
+	struct clk	*mck;
+};
+
+static inline struct pit_data *clksrc_to_pit_data(struct clocksource *clksrc)
+{
+	return container_of(clksrc, struct pit_data, clksrc);
+}
+
+static inline struct pit_data *clkevt_to_pit_data(struct clock_event_device *clkevt)
+{
+	return container_of(clkevt, struct pit_data, clkevt);
+}
+
+static inline unsigned int pit_read(void __iomem *base, unsigned int reg_offset)
+{
+	return readl_relaxed(base + reg_offset);
+}
+
+static inline void pit_write(void __iomem *base, unsigned int reg_offset, unsigned long value)
+{
+	writel_relaxed(value, base + reg_offset);
+}
+
+/*
+ * Clocksource:  just a monotonic counter of MCK/16 cycles.
+ * We don't care whether or not PIT irqs are enabled.
+ */
+static u64 read_pit_clk(struct clocksource *cs)
+{
+	struct pit_data *data = clksrc_to_pit_data(cs);
+	unsigned long flags;
+	u32 elapsed;
+	u32 t;
+
+	raw_local_irq_save(flags);
+	elapsed = data->cnt;
+	t = pit_read(data->base, AT91_PIT_PIIR);
+	raw_local_irq_restore(flags);
+
+	elapsed += PIT_PICNT(t) * data->cycle;
+	elapsed += PIT_CPIV(t);
+	return elapsed;
+}
+
+static int pit_clkevt_shutdown(struct clock_event_device *dev)
+{
+	struct pit_data *data = clkevt_to_pit_data(dev);
+
+	/* disable irq, leaving the clocksource active */
+	pit_write(data->base, AT91_PIT_MR, (data->cycle - 1) | AT91_PIT_PITEN);
+	return 0;
+}
+
+/*
+ * Clockevent device:  interrupts every 1/HZ (== pit_cycles * MCK/16)
+ */
+static int pit_clkevt_set_periodic(struct clock_event_device *dev)
+{
+	struct pit_data *data = clkevt_to_pit_data(dev);
+
+	/* update clocksource counter */
+	data->cnt += data->cycle * PIT_PICNT(pit_read(data->base, AT91_PIT_PIVR));
+	pit_write(data->base, AT91_PIT_MR,
+		  (data->cycle - 1) | AT91_PIT_PITEN | AT91_PIT_PITIEN);
+	return 0;
+}
+
+static void at91sam926x_pit_suspend(struct clock_event_device *cedev)
+{
+	struct pit_data *data = clkevt_to_pit_data(cedev);
+
+	/* Disable timer */
+	pit_write(data->base, AT91_PIT_MR, 0);
+}
+
+static void at91sam926x_pit_reset(struct pit_data *data)
+{
+	/* Disable timer and irqs */
+	pit_write(data->base, AT91_PIT_MR, 0);
+
+	/* Clear any pending interrupts, wait for PIT to stop counting */
+	while (PIT_CPIV(pit_read(data->base, AT91_PIT_PIVR)) != 0)
+		cpu_relax();
+
+	/* Start PIT but don't enable IRQ */
+	pit_write(data->base, AT91_PIT_MR,
+		  (data->cycle - 1) | AT91_PIT_PITEN);
+}
+
+static void at91sam926x_pit_resume(struct clock_event_device *cedev)
+{
+	struct pit_data *data = clkevt_to_pit_data(cedev);
+
+	at91sam926x_pit_reset(data);
+}
+
+/*
+ * IRQ handler for the timer.
+ */
+static irqreturn_t at91sam926x_pit_interrupt(int irq, void *dev_id)
+{
+	struct pit_data *data = dev_id;
+
+	/* The PIT interrupt may be disabled, and is shared */
+	if (clockevent_state_periodic(&data->clkevt) &&
+	    (pit_read(data->base, AT91_PIT_SR) & AT91_PIT_PITS)) {
+		/* Get number of ticks performed before irq, and ack it */
+		data->cnt += data->cycle * PIT_PICNT(pit_read(data->base,
+							      AT91_PIT_PIVR));
+		data->clkevt.event_handler(&data->clkevt);
+
+		return IRQ_HANDLED;
+	}
+
+	return IRQ_NONE;
+}
+
+/*
+ * Set up both clocksource and clockevent support.
+ */
+static int __init at91sam926x_pit_dt_init(struct device_node *node)
+{
+	unsigned long   pit_rate;
+	unsigned        bits;
+	int             ret;
+	struct pit_data *data;
+
+	data = kzalloc(sizeof(*data), GFP_KERNEL);
+	if (!data)
+		return -ENOMEM;
+
+	data->base = of_iomap(node, 0);
+	if (!data->base) {
+		pr_err("Could not map PIT address\n");
+		ret = -ENXIO;
+		goto exit;
+	}
+
+	data->mck = of_clk_get(node, 0);
+	if (IS_ERR(data->mck)) {
+		pr_err("Unable to get mck clk\n");
+		ret = PTR_ERR(data->mck);
+		goto exit;
+	}
+
+	ret = clk_prepare_enable(data->mck);
+	if (ret) {
+		pr_err("Unable to enable mck\n");
+		goto exit;
+	}
+
+	/* Get the interrupts property */
+	data->irq = irq_of_parse_and_map(node, 0);
+	if (!data->irq) {
+		pr_err("Unable to get IRQ from DT\n");
+		ret = -EINVAL;
+		goto exit;
+	}
+
+	/*
+	 * Use our actual MCK to figure out how many MCK/16 ticks per
+	 * 1/HZ period (instead of a compile-time constant LATCH).
+	 */
+	pit_rate = clk_get_rate(data->mck) / 16;
+	data->cycle = DIV_ROUND_CLOSEST(pit_rate, HZ);
+	WARN_ON(((data->cycle - 1) & ~AT91_PIT_PIV) != 0);
+
+	/* Initialize and enable the timer */
+	at91sam926x_pit_reset(data);
+
+	/*
+	 * Register clocksource.  The high order bits of PIV are unused,
+	 * so this isn't a 32-bit counter unless we get clockevent irqs.
+	 */
+	bits = 12 /* PICNT */ + ilog2(data->cycle) /* PIV */;
+	data->clksrc.mask = CLOCKSOURCE_MASK(bits);
+	data->clksrc.name = "pit";
+	data->clksrc.rating = 175;
+	data->clksrc.read = read_pit_clk;
+	data->clksrc.flags = CLOCK_SOURCE_IS_CONTINUOUS;
+	
+	ret = clocksource_register_hz(&data->clksrc, pit_rate);
+	if (ret) {
+		pr_err("Failed to register clocksource\n");
+		goto exit;
+	}
+
+	/* Set up irq handler */
+	ret = request_irq(data->irq, at91sam926x_pit_interrupt,
+			  IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
+			  "at91_tick", data);
+	if (ret) {
+		pr_err("Unable to setup IRQ\n");
+		clocksource_unregister(&data->clksrc);
+		goto exit;
+	}
+
+	/* Set up and register clockevents */
+	data->clkevt.name = "pit";
+	data->clkevt.features = CLOCK_EVT_FEAT_PERIODIC;
+	data->clkevt.shift = 32;
+	data->clkevt.mult = div_sc(pit_rate, NSEC_PER_SEC, data->clkevt.shift);
+	data->clkevt.rating = 100;
+	data->clkevt.cpumask = cpumask_of(0);
+
+	data->clkevt.set_state_shutdown = pit_clkevt_shutdown;
+	data->clkevt.set_state_periodic = pit_clkevt_set_periodic;
+	data->clkevt.resume = at91sam926x_pit_resume;
+	data->clkevt.suspend = at91sam926x_pit_suspend;
+	clockevents_register_device(&data->clkevt);
+
+	return 0;
+
+exit:
+	kfree(data);
+	return ret;
+}
+TIMER_OF_DECLARE(at91sam926x_pit, "atmel,at91sam9260-pit",
+		       at91sam926x_pit_dt_init);

drivers/clocksource/timer-atmel-st.c

@@ -0,0 +1,264 @@
+/*
+ * linux/arch/arm/mach-at91/at91rm9200_time.c
+ *
+ *  Copyright (C) 2003 SAN People
+ *  Copyright (C) 2003 ATMEL
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/export.h>
+#include <linux/mfd/syscon.h>
+#include <linux/mfd/syscon/atmel-st.h>
+#include <linux/of_irq.h>
+#include <linux/regmap.h>
+
+static unsigned long last_crtr;
+static u32 irqmask;
+static struct clock_event_device clkevt;
+static struct regmap *regmap_st;
+static int timer_latch;
+
+/*
+ * The ST_CRTR is updated asynchronously to the master clock ... but
+ * the updates as seen by the CPU don't seem to be strictly monotonic.
+ * Waiting until we read the same value twice avoids glitching.
+ */
+static inline unsigned long read_CRTR(void)
+{
+	unsigned int x1, x2;
+
+	regmap_read(regmap_st, AT91_ST_CRTR, &x1);
+	do {
+		regmap_read(regmap_st, AT91_ST_CRTR, &x2);
+		if (x1 == x2)
+			break;
+		x1 = x2;
+	} while (1);
+	return x1;
+}
+
+/*
+ * IRQ handler for the timer.
+ */
+static irqreturn_t at91rm9200_timer_interrupt(int irq, void *dev_id)
+{
+	u32 sr;
+
+	regmap_read(regmap_st, AT91_ST_SR, &sr);
+	sr &= irqmask;
+
+	/*
+	 * irqs should be disabled here, but as the irq is shared they are only
+	 * guaranteed to be off if the timer irq is registered first.
+	 */
+	WARN_ON_ONCE(!irqs_disabled());
+
+	/* simulate "oneshot" timer with alarm */
+	if (sr & AT91_ST_ALMS) {
+		clkevt.event_handler(&clkevt);
+		return IRQ_HANDLED;
+	}
+
+	/* periodic mode should handle delayed ticks */
+	if (sr & AT91_ST_PITS) {
+		u32	crtr = read_CRTR();
+
+		while (((crtr - last_crtr) & AT91_ST_CRTV) >= timer_latch) {
+			last_crtr += timer_latch;
+			clkevt.event_handler(&clkevt);
+		}
+		return IRQ_HANDLED;
+	}
+
+	/* this irq is shared ... */
+	return IRQ_NONE;
+}
+
+static u64 read_clk32k(struct clocksource *cs)
+{
+	return read_CRTR();
+}
+
+static struct clocksource clk32k = {
+	.name		= "32k_counter",
+	.rating		= 150,
+	.read		= read_clk32k,
+	.mask		= CLOCKSOURCE_MASK(20),
+	.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static void clkdev32k_disable_and_flush_irq(void)
+{
+	unsigned int val;
+
+	/* Disable and flush pending timer interrupts */
+	regmap_write(regmap_st, AT91_ST_IDR, AT91_ST_PITS | AT91_ST_ALMS);
+	regmap_read(regmap_st, AT91_ST_SR, &val);
+	last_crtr = read_CRTR();
+}
+
+static int clkevt32k_shutdown(struct clock_event_device *evt)
+{
+	clkdev32k_disable_and_flush_irq();
+	irqmask = 0;
+	regmap_write(regmap_st, AT91_ST_IER, irqmask);
+	return 0;
+}
+
+static int clkevt32k_set_oneshot(struct clock_event_device *dev)
+{
+	clkdev32k_disable_and_flush_irq();
+
+	/*
+	 * ALM for oneshot irqs, set by next_event()
+	 * before 32 seconds have passed.
+	 */
+	irqmask = AT91_ST_ALMS;
+	regmap_write(regmap_st, AT91_ST_RTAR, last_crtr);
+	regmap_write(regmap_st, AT91_ST_IER, irqmask);
+	return 0;
+}
+
+static int clkevt32k_set_periodic(struct clock_event_device *dev)
+{
+	clkdev32k_disable_and_flush_irq();
+
+	/* PIT for periodic irqs; fixed rate of 1/HZ */
+	irqmask = AT91_ST_PITS;
+	regmap_write(regmap_st, AT91_ST_PIMR, timer_latch);
+	regmap_write(regmap_st, AT91_ST_IER, irqmask);
+	return 0;
+}
+
+static int
+clkevt32k_next_event(unsigned long delta, struct clock_event_device *dev)
+{
+	u32		alm;
+	int		status = 0;
+	unsigned int	val;
+
+	BUG_ON(delta < 2);
+
+	/* The alarm IRQ uses absolute time (now+delta), not the relative
+	 * time (delta) in our calling convention.  Like all clockevents
+	 * using such "match" hardware, we have a race to defend against.
+	 *
+	 * Our defense here is to have set up the clockevent device so the
+	 * delta is at least two.  That way we never end up writing RTAR
+	 * with the value then held in CRTR ... which would mean the match
+	 * wouldn't trigger until 32 seconds later, after CRTR wraps.
+	 */
+	alm = read_CRTR();
+
+	/* Cancel any pending alarm; flush any pending IRQ */
+	regmap_write(regmap_st, AT91_ST_RTAR, alm);
+	regmap_read(regmap_st, AT91_ST_SR, &val);
+
+	/* Schedule alarm by writing RTAR. */
+	alm += delta;
+	regmap_write(regmap_st, AT91_ST_RTAR, alm);
+
+	return status;
+}
+
+static struct clock_event_device clkevt = {
+	.name			= "at91_tick",
+	.features		= CLOCK_EVT_FEAT_PERIODIC |
+				  CLOCK_EVT_FEAT_ONESHOT,
+	.rating			= 150,
+	.set_next_event		= clkevt32k_next_event,
+	.set_state_shutdown	= clkevt32k_shutdown,
+	.set_state_periodic	= clkevt32k_set_periodic,
+	.set_state_oneshot	= clkevt32k_set_oneshot,
+	.tick_resume		= clkevt32k_shutdown,
+};
+
+/*
+ * ST (system timer) module supports both clockevents and clocksource.
+ */
+static int __init atmel_st_timer_init(struct device_node *node)
+{
+	struct clk *sclk;
+	unsigned int sclk_rate, val;
+	int irq, ret;
+
+	regmap_st = syscon_node_to_regmap(node);
+	if (IS_ERR(regmap_st)) {
+		pr_err("Unable to get regmap\n");
+		return PTR_ERR(regmap_st);
+	}
+
+	/* Disable all timer interrupts, and clear any pending ones */
+	regmap_write(regmap_st, AT91_ST_IDR,
+		AT91_ST_PITS | AT91_ST_WDOVF | AT91_ST_RTTINC | AT91_ST_ALMS);
+	regmap_read(regmap_st, AT91_ST_SR, &val);
+
+	/* Get the interrupts property */
+	irq  = irq_of_parse_and_map(node, 0);
+	if (!irq) {
+		pr_err("Unable to get IRQ from DT\n");
+		return -EINVAL;
+	}
+
+	/* Make IRQs happen for the system timer */
+	ret = request_irq(irq, at91rm9200_timer_interrupt,
+			  IRQF_SHARED | IRQF_TIMER | IRQF_IRQPOLL,
+			  "at91_tick", regmap_st);
+	if (ret) {
+		pr_err("Unable to setup IRQ\n");
+		return ret;
+	}
+
+	sclk = of_clk_get(node, 0);
+	if (IS_ERR(sclk)) {
+		pr_err("Unable to get slow clock\n");
+		return PTR_ERR(sclk);
+	}
+
+	ret = clk_prepare_enable(sclk);
+	if (ret) {
+		pr_err("Could not enable slow clock\n");
+		return ret;
+	}
+
+	sclk_rate = clk_get_rate(sclk);
+	if (!sclk_rate) {
+		pr_err("Invalid slow clock rate\n");
+		return -EINVAL;
+	}
+	timer_latch = (sclk_rate + HZ / 2) / HZ;
+
+	/* The 32KiHz "Slow Clock" (tick every 30517.58 nanoseconds) is used
+	 * directly for the clocksource and all clockevents, after adjusting
+	 * its prescaler from the 1 Hz default.
+	 */
+	regmap_write(regmap_st, AT91_ST_RTMR, 1);
+
+	/* Setup timer clockevent, with minimum of two ticks (important!!) */
+	clkevt.cpumask = cpumask_of(0);
+	clockevents_config_and_register(&clkevt, sclk_rate,
+					2, AT91_ST_ALMV);
+
+	/* register clocksource */
+	return clocksource_register_hz(&clk32k, sclk_rate);
+}
+TIMER_OF_DECLARE(atmel_st_timer, "atmel,at91rm9200-st",
+		       atmel_st_timer_init);

drivers/clocksource/timer-digicolor.c

@@ -0,0 +1,207 @@
+/*
+ * Conexant Digicolor timer driver
+ *
+ * Author: Baruch Siach <baruch@tkos.co.il>
+ *
+ * Copyright (C) 2014 Paradox Innovation Ltd.
+ *
+ * Based on:
+ *	Allwinner SoCs hstimer driver
+ *
+ * Copyright (C) 2013 Maxime Ripard
+ *
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+/*
+ * Conexant Digicolor SoCs have 8 configurable timers, named from "Timer A" to
+ * "Timer H". Timer A is the only one with watchdog support, so it is dedicated
+ * to the watchdog driver. This driver uses Timer B for sched_clock(), and
+ * Timer C for clockevents.
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqreturn.h>
+#include <linux/sched/clock.h>
+#include <linux/sched_clock.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+enum {
+	TIMER_A,
+	TIMER_B,
+	TIMER_C,
+	TIMER_D,
+	TIMER_E,
+	TIMER_F,
+	TIMER_G,
+	TIMER_H,
+};
+
+#define CONTROL(t)	((t)*8)
+#define COUNT(t)	((t)*8 + 4)
+
+#define CONTROL_DISABLE		0
+#define CONTROL_ENABLE		BIT(0)
+#define CONTROL_MODE(m)		((m) << 4)
+#define CONTROL_MODE_ONESHOT	CONTROL_MODE(1)
+#define CONTROL_MODE_PERIODIC	CONTROL_MODE(2)
+
+struct digicolor_timer {
+	struct clock_event_device ce;
+	void __iomem *base;
+	u32 ticks_per_jiffy;
+	int timer_id; /* one of TIMER_* */
+};
+
+static struct digicolor_timer *dc_timer(struct clock_event_device *ce)
+{
+	return container_of(ce, struct digicolor_timer, ce);
+}
+
+static inline void dc_timer_disable(struct clock_event_device *ce)
+{
+	struct digicolor_timer *dt = dc_timer(ce);
+	writeb(CONTROL_DISABLE, dt->base + CONTROL(dt->timer_id));
+}
+
+static inline void dc_timer_enable(struct clock_event_device *ce, u32 mode)
+{
+	struct digicolor_timer *dt = dc_timer(ce);
+	writeb(CONTROL_ENABLE | mode, dt->base + CONTROL(dt->timer_id));
+}
+
+static inline void dc_timer_set_count(struct clock_event_device *ce,
+				      unsigned long count)
+{
+	struct digicolor_timer *dt = dc_timer(ce);
+	writel(count, dt->base + COUNT(dt->timer_id));
+}
+
+static int digicolor_clkevt_shutdown(struct clock_event_device *ce)
+{
+	dc_timer_disable(ce);
+	return 0;
+}
+
+static int digicolor_clkevt_set_oneshot(struct clock_event_device *ce)
+{
+	dc_timer_disable(ce);
+	dc_timer_enable(ce, CONTROL_MODE_ONESHOT);
+	return 0;
+}
+
+static int digicolor_clkevt_set_periodic(struct clock_event_device *ce)
+{
+	struct digicolor_timer *dt = dc_timer(ce);
+
+	dc_timer_disable(ce);
+	dc_timer_set_count(ce, dt->ticks_per_jiffy);
+	dc_timer_enable(ce, CONTROL_MODE_PERIODIC);
+	return 0;
+}
+
+static int digicolor_clkevt_next_event(unsigned long evt,
+				       struct clock_event_device *ce)
+{
+	dc_timer_disable(ce);
+	dc_timer_set_count(ce, evt);
+	dc_timer_enable(ce, CONTROL_MODE_ONESHOT);
+
+	return 0;
+}
+
+static struct digicolor_timer dc_timer_dev = {
+	.ce = {
+		.name = "digicolor_tick",
+		.rating = 340,
+		.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+		.set_state_shutdown = digicolor_clkevt_shutdown,
+		.set_state_periodic = digicolor_clkevt_set_periodic,
+		.set_state_oneshot = digicolor_clkevt_set_oneshot,
+		.tick_resume = digicolor_clkevt_shutdown,
+		.set_next_event = digicolor_clkevt_next_event,
+	},
+	.timer_id = TIMER_C,
+};
+
+static irqreturn_t digicolor_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static u64 notrace digicolor_timer_sched_read(void)
+{
+	return ~readl(dc_timer_dev.base + COUNT(TIMER_B));
+}
+
+static int __init digicolor_timer_init(struct device_node *node)
+{
+	unsigned long rate;
+	struct clk *clk;
+	int ret, irq;
+
+	/*
+	 * timer registers are shared with the watchdog timer;
+	 * don't map exclusively
+	 */
+	dc_timer_dev.base = of_iomap(node, 0);
+	if (!dc_timer_dev.base) {
+		pr_err("Can't map registers\n");
+		return -ENXIO;
+	}
+
+	irq = irq_of_parse_and_map(node, dc_timer_dev.timer_id);
+	if (irq <= 0) {
+		pr_err("Can't parse IRQ\n");
+		return -EINVAL;
+	}
+
+	clk = of_clk_get(node, 0);
+	if (IS_ERR(clk)) {
+		pr_err("Can't get timer clock\n");
+		return PTR_ERR(clk);
+	}
+	clk_prepare_enable(clk);
+	rate = clk_get_rate(clk);
+	dc_timer_dev.ticks_per_jiffy = DIV_ROUND_UP(rate, HZ);
+
+	writeb(CONTROL_DISABLE, dc_timer_dev.base + CONTROL(TIMER_B));
+	writel(UINT_MAX, dc_timer_dev.base + COUNT(TIMER_B));
+	writeb(CONTROL_ENABLE, dc_timer_dev.base + CONTROL(TIMER_B));
+
+	sched_clock_register(digicolor_timer_sched_read, 32, rate);
+	clocksource_mmio_init(dc_timer_dev.base + COUNT(TIMER_B), node->name,
+			      rate, 340, 32, clocksource_mmio_readl_down);
+
+	ret = request_irq(irq, digicolor_timer_interrupt,
+			  IRQF_TIMER | IRQF_IRQPOLL, "digicolor_timerC",
+			  &dc_timer_dev.ce);
+	if (ret) {
+		pr_warn("request of timer irq %d failed (%d)\n", irq, ret);
+		return ret;
+	}
+
+	dc_timer_dev.ce.cpumask = cpu_possible_mask;
+	dc_timer_dev.ce.irq = irq;
+
+	clockevents_config_and_register(&dc_timer_dev.ce, rate, 0, 0xffffffff);
+
+	return 0;
+}
+TIMER_OF_DECLARE(conexant_digicolor, "cnxt,cx92755-timer",
+		       digicolor_timer_init);

drivers/clocksource/timer-fttmr010.c

@@ -0,0 +1,421 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Faraday Technology FTTMR010 timer driver
+ * Copyright (C) 2017 Linus Walleij <linus.walleij@linaro.org>
+ *
+ * Based on a rewrite of arch/arm/mach-gemini/timer.c:
+ * Copyright (C) 2001-2006 Storlink, Corp.
+ * Copyright (C) 2008-2009 Paulius Zaleckas <paulius.zaleckas@teltonika.lt>
+ */
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/sched_clock.h>
+#include <linux/clk.h>
+#include <linux/slab.h>
+#include <linux/bitops.h>
+#include <linux/delay.h>
+
+/*
+ * Register definitions common for all the timer variants.
+ */
+#define TIMER1_COUNT		(0x00)
+#define TIMER1_LOAD		(0x04)
+#define TIMER1_MATCH1		(0x08)
+#define TIMER1_MATCH2		(0x0c)
+#define TIMER2_COUNT		(0x10)
+#define TIMER2_LOAD		(0x14)
+#define TIMER2_MATCH1		(0x18)
+#define TIMER2_MATCH2		(0x1c)
+#define TIMER3_COUNT		(0x20)
+#define TIMER3_LOAD		(0x24)
+#define TIMER3_MATCH1		(0x28)
+#define TIMER3_MATCH2		(0x2c)
+#define TIMER_CR		(0x30)
+
+/*
+ * Control register (TMC30) bit fields for fttmr010/gemini/moxart timers.
+ */
+#define TIMER_1_CR_ENABLE	BIT(0)
+#define TIMER_1_CR_CLOCK	BIT(1)
+#define TIMER_1_CR_INT		BIT(2)
+#define TIMER_2_CR_ENABLE	BIT(3)
+#define TIMER_2_CR_CLOCK	BIT(4)
+#define TIMER_2_CR_INT		BIT(5)
+#define TIMER_3_CR_ENABLE	BIT(6)
+#define TIMER_3_CR_CLOCK	BIT(7)
+#define TIMER_3_CR_INT		BIT(8)
+#define TIMER_1_CR_UPDOWN	BIT(9)
+#define TIMER_2_CR_UPDOWN	BIT(10)
+#define TIMER_3_CR_UPDOWN	BIT(11)
+
+/*
+ * Control register (TMC30) bit fields for aspeed ast2400/ast2500 timers.
+ * The aspeed timers move bits around in the control register and lacks
+ * bits for setting the timer to count upwards.
+ */
+#define TIMER_1_CR_ASPEED_ENABLE	BIT(0)
+#define TIMER_1_CR_ASPEED_CLOCK		BIT(1)
+#define TIMER_1_CR_ASPEED_INT		BIT(2)
+#define TIMER_2_CR_ASPEED_ENABLE	BIT(4)
+#define TIMER_2_CR_ASPEED_CLOCK		BIT(5)
+#define TIMER_2_CR_ASPEED_INT		BIT(6)
+#define TIMER_3_CR_ASPEED_ENABLE	BIT(8)
+#define TIMER_3_CR_ASPEED_CLOCK		BIT(9)
+#define TIMER_3_CR_ASPEED_INT		BIT(10)
+
+/*
+ * Interrupt status/mask register definitions for fttmr010/gemini/moxart
+ * timers.
+ * The registers don't exist and they are not needed on aspeed timers
+ * because:
+ *   - aspeed timer overflow interrupt is controlled by bits in Control
+ *     Register (TMC30).
+ *   - aspeed timers always generate interrupt when either one of the
+ *     Match registers equals to Status register.
+ */
+#define TIMER_INTR_STATE	(0x34)
+#define TIMER_INTR_MASK		(0x38)
+#define TIMER_1_INT_MATCH1	BIT(0)
+#define TIMER_1_INT_MATCH2	BIT(1)
+#define TIMER_1_INT_OVERFLOW	BIT(2)
+#define TIMER_2_INT_MATCH1	BIT(3)
+#define TIMER_2_INT_MATCH2	BIT(4)
+#define TIMER_2_INT_OVERFLOW	BIT(5)
+#define TIMER_3_INT_MATCH1	BIT(6)
+#define TIMER_3_INT_MATCH2	BIT(7)
+#define TIMER_3_INT_OVERFLOW	BIT(8)
+#define TIMER_INT_ALL_MASK	0x1ff
+
+struct fttmr010 {
+	void __iomem *base;
+	unsigned int tick_rate;
+	bool is_aspeed;
+	u32 t1_enable_val;
+	struct clock_event_device clkevt;
+#ifdef CONFIG_ARM
+	struct delay_timer delay_timer;
+#endif
+};
+
+/*
+ * A local singleton used by sched_clock and delay timer reads, which are
+ * fast and stateless
+ */
+static struct fttmr010 *local_fttmr;
+
+static inline struct fttmr010 *to_fttmr010(struct clock_event_device *evt)
+{
+	return container_of(evt, struct fttmr010, clkevt);
+}
+
+static unsigned long fttmr010_read_current_timer_up(void)
+{
+	return readl(local_fttmr->base + TIMER2_COUNT);
+}
+
+static unsigned long fttmr010_read_current_timer_down(void)
+{
+	return ~readl(local_fttmr->base + TIMER2_COUNT);
+}
+
+static u64 notrace fttmr010_read_sched_clock_up(void)
+{
+	return fttmr010_read_current_timer_up();
+}
+
+static u64 notrace fttmr010_read_sched_clock_down(void)
+{
+	return fttmr010_read_current_timer_down();
+}
+
+static int fttmr010_timer_set_next_event(unsigned long cycles,
+				       struct clock_event_device *evt)
+{
+	struct fttmr010 *fttmr010 = to_fttmr010(evt);
+	u32 cr;
+
+	/* Stop */
+	cr = readl(fttmr010->base + TIMER_CR);
+	cr &= ~fttmr010->t1_enable_val;
+	writel(cr, fttmr010->base + TIMER_CR);
+
+	if (fttmr010->is_aspeed) {
+		/*
+		 * ASPEED Timer Controller will load TIMER1_LOAD register
+		 * into TIMER1_COUNT register when the timer is re-enabled.
+		 */
+		writel(cycles, fttmr010->base + TIMER1_LOAD);
+	} else {
+		/* Setup the match register forward in time */
+		cr = readl(fttmr010->base + TIMER1_COUNT);
+		writel(cr + cycles, fttmr010->base + TIMER1_MATCH1);
+	}
+
+	/* Start */
+	cr = readl(fttmr010->base + TIMER_CR);
+	cr |= fttmr010->t1_enable_val;
+	writel(cr, fttmr010->base + TIMER_CR);
+
+	return 0;
+}
+
+static int fttmr010_timer_shutdown(struct clock_event_device *evt)
+{
+	struct fttmr010 *fttmr010 = to_fttmr010(evt);
+	u32 cr;
+
+	/* Stop */
+	cr = readl(fttmr010->base + TIMER_CR);
+	cr &= ~fttmr010->t1_enable_val;
+	writel(cr, fttmr010->base + TIMER_CR);
+
+	return 0;
+}
+
+static int fttmr010_timer_set_oneshot(struct clock_event_device *evt)
+{
+	struct fttmr010 *fttmr010 = to_fttmr010(evt);
+	u32 cr;
+
+	/* Stop */
+	cr = readl(fttmr010->base + TIMER_CR);
+	cr &= ~fttmr010->t1_enable_val;
+	writel(cr, fttmr010->base + TIMER_CR);
+
+	/* Setup counter start from 0 or ~0 */
+	writel(0, fttmr010->base + TIMER1_COUNT);
+	if (fttmr010->is_aspeed) {
+		writel(~0, fttmr010->base + TIMER1_LOAD);
+	} else {
+		writel(0, fttmr010->base + TIMER1_LOAD);
+
+		/* Enable interrupt */
+		cr = readl(fttmr010->base + TIMER_INTR_MASK);
+		cr &= ~(TIMER_1_INT_OVERFLOW | TIMER_1_INT_MATCH2);
+		cr |= TIMER_1_INT_MATCH1;
+		writel(cr, fttmr010->base + TIMER_INTR_MASK);
+	}
+
+	return 0;
+}
+
+static int fttmr010_timer_set_periodic(struct clock_event_device *evt)
+{
+	struct fttmr010 *fttmr010 = to_fttmr010(evt);
+	u32 period = DIV_ROUND_CLOSEST(fttmr010->tick_rate, HZ);
+	u32 cr;
+
+	/* Stop */
+	cr = readl(fttmr010->base + TIMER_CR);
+	cr &= ~fttmr010->t1_enable_val;
+	writel(cr, fttmr010->base + TIMER_CR);
+
+	/* Setup timer to fire at 1/HZ intervals. */
+	if (fttmr010->is_aspeed) {
+		writel(period, fttmr010->base + TIMER1_LOAD);
+	} else {
+		cr = 0xffffffff - (period - 1);
+		writel(cr, fttmr010->base + TIMER1_COUNT);
+		writel(cr, fttmr010->base + TIMER1_LOAD);
+
+		/* Enable interrupt on overflow */
+		cr = readl(fttmr010->base + TIMER_INTR_MASK);
+		cr &= ~(TIMER_1_INT_MATCH1 | TIMER_1_INT_MATCH2);
+		cr |= TIMER_1_INT_OVERFLOW;
+		writel(cr, fttmr010->base + TIMER_INTR_MASK);
+	}
+
+	/* Start the timer */
+	cr = readl(fttmr010->base + TIMER_CR);
+	cr |= fttmr010->t1_enable_val;
+	writel(cr, fttmr010->base + TIMER_CR);
+
+	return 0;
+}
+
+/*
+ * IRQ handler for the timer
+ */
+static irqreturn_t fttmr010_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	evt->event_handler(evt);
+	return IRQ_HANDLED;
+}
+
+static int __init fttmr010_common_init(struct device_node *np, bool is_aspeed)
+{
+	struct fttmr010 *fttmr010;
+	int irq;
+	struct clk *clk;
+	int ret;
+	u32 val;
+
+	/*
+	 * These implementations require a clock reference.
+	 * FIXME: we currently only support clocking using PCLK
+	 * and using EXTCLK is not supported in the driver.
+	 */
+	clk = of_clk_get_by_name(np, "PCLK");
+	if (IS_ERR(clk)) {
+		pr_err("could not get PCLK\n");
+		return PTR_ERR(clk);
+	}
+	ret = clk_prepare_enable(clk);
+	if (ret) {
+		pr_err("failed to enable PCLK\n");
+		return ret;
+	}
+
+	fttmr010 = kzalloc(sizeof(*fttmr010), GFP_KERNEL);
+	if (!fttmr010) {
+		ret = -ENOMEM;
+		goto out_disable_clock;
+	}
+	fttmr010->tick_rate = clk_get_rate(clk);
+
+	fttmr010->base = of_iomap(np, 0);
+	if (!fttmr010->base) {
+		pr_err("Can't remap registers\n");
+		ret = -ENXIO;
+		goto out_free;
+	}
+	/* IRQ for timer 1 */
+	irq = irq_of_parse_and_map(np, 0);
+	if (irq <= 0) {
+		pr_err("Can't parse IRQ\n");
+		ret = -EINVAL;
+		goto out_unmap;
+	}
+
+	/*
+	 * The Aspeed timers move bits around in the control register.
+	 */
+	if (is_aspeed) {
+		fttmr010->t1_enable_val = TIMER_1_CR_ASPEED_ENABLE |
+			TIMER_1_CR_ASPEED_INT;
+		fttmr010->is_aspeed = true;
+	} else {
+		fttmr010->t1_enable_val = TIMER_1_CR_ENABLE | TIMER_1_CR_INT;
+
+		/*
+		 * Reset the interrupt mask and status
+		 */
+		writel(TIMER_INT_ALL_MASK, fttmr010->base + TIMER_INTR_MASK);
+		writel(0, fttmr010->base + TIMER_INTR_STATE);
+	}
+
+	/*
+	 * Enable timer 1 count up, timer 2 count up, except on Aspeed,
+	 * where everything just counts down.
+	 */
+	if (is_aspeed)
+		val = TIMER_2_CR_ASPEED_ENABLE;
+	else {
+		val = TIMER_2_CR_ENABLE | TIMER_1_CR_UPDOWN |
+			TIMER_2_CR_UPDOWN;
+	}
+	writel(val, fttmr010->base + TIMER_CR);
+
+	/*
+	 * Setup free-running clocksource timer (interrupts
+	 * disabled.)
+	 */
+	local_fttmr = fttmr010;
+	writel(0, fttmr010->base + TIMER2_COUNT);
+	writel(0, fttmr010->base + TIMER2_MATCH1);
+	writel(0, fttmr010->base + TIMER2_MATCH2);
+
+	if (fttmr010->is_aspeed) {
+		writel(~0, fttmr010->base + TIMER2_LOAD);
+		clocksource_mmio_init(fttmr010->base + TIMER2_COUNT,
+				      "FTTMR010-TIMER2",
+				      fttmr010->tick_rate,
+				      300, 32, clocksource_mmio_readl_down);
+		sched_clock_register(fttmr010_read_sched_clock_down, 32,
+				     fttmr010->tick_rate);
+	} else {
+		writel(0, fttmr010->base + TIMER2_LOAD);
+		clocksource_mmio_init(fttmr010->base + TIMER2_COUNT,
+				      "FTTMR010-TIMER2",
+				      fttmr010->tick_rate,
+				      300, 32, clocksource_mmio_readl_up);
+		sched_clock_register(fttmr010_read_sched_clock_up, 32,
+				     fttmr010->tick_rate);
+	}
+
+	/*
+	 * Setup clockevent timer (interrupt-driven) on timer 1.
+	 */
+	writel(0, fttmr010->base + TIMER1_COUNT);
+	writel(0, fttmr010->base + TIMER1_LOAD);
+	writel(0, fttmr010->base + TIMER1_MATCH1);
+	writel(0, fttmr010->base + TIMER1_MATCH2);
+	ret = request_irq(irq, fttmr010_timer_interrupt, IRQF_TIMER,
+			  "FTTMR010-TIMER1", &fttmr010->clkevt);
+	if (ret) {
+		pr_err("FTTMR010-TIMER1 no IRQ\n");
+		goto out_unmap;
+	}
+
+	fttmr010->clkevt.name = "FTTMR010-TIMER1";
+	/* Reasonably fast and accurate clock event */
+	fttmr010->clkevt.rating = 300;
+	fttmr010->clkevt.features = CLOCK_EVT_FEAT_PERIODIC |
+		CLOCK_EVT_FEAT_ONESHOT;
+	fttmr010->clkevt.set_next_event = fttmr010_timer_set_next_event;
+	fttmr010->clkevt.set_state_shutdown = fttmr010_timer_shutdown;
+	fttmr010->clkevt.set_state_periodic = fttmr010_timer_set_periodic;
+	fttmr010->clkevt.set_state_oneshot = fttmr010_timer_set_oneshot;
+	fttmr010->clkevt.tick_resume = fttmr010_timer_shutdown;
+	fttmr010->clkevt.cpumask = cpumask_of(0);
+	fttmr010->clkevt.irq = irq;
+	clockevents_config_and_register(&fttmr010->clkevt,
+					fttmr010->tick_rate,
+					1, 0xffffffff);
+
+#ifdef CONFIG_ARM
+	/* Also use this timer for delays */
+	if (fttmr010->is_aspeed)
+		fttmr010->delay_timer.read_current_timer =
+			fttmr010_read_current_timer_down;
+	else
+		fttmr010->delay_timer.read_current_timer =
+			fttmr010_read_current_timer_up;
+	fttmr010->delay_timer.freq = fttmr010->tick_rate;
+	register_current_timer_delay(&fttmr010->delay_timer);
+#endif
+
+	return 0;
+
+out_unmap:
+	iounmap(fttmr010->base);
+out_free:
+	kfree(fttmr010);
+out_disable_clock:
+	clk_disable_unprepare(clk);
+
+	return ret;
+}
+
+static __init int aspeed_timer_init(struct device_node *np)
+{
+	return fttmr010_common_init(np, true);
+}
+
+static __init int fttmr010_timer_init(struct device_node *np)
+{
+	return fttmr010_common_init(np, false);
+}
+
+TIMER_OF_DECLARE(fttmr010, "faraday,fttmr010", fttmr010_timer_init);
+TIMER_OF_DECLARE(gemini, "cortina,gemini-timer", fttmr010_timer_init);
+TIMER_OF_DECLARE(moxart, "moxa,moxart-timer", fttmr010_timer_init);
+TIMER_OF_DECLARE(ast2400, "aspeed,ast2400-timer", aspeed_timer_init);
+TIMER_OF_DECLARE(ast2500, "aspeed,ast2500-timer", aspeed_timer_init);

drivers/clocksource/timer-imx-gpt.c

@@ -0,0 +1,543 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+//  Copyright (C) 2000-2001 Deep Blue Solutions
+//  Copyright (C) 2002 Shane Nay (shane@minirl.com)
+//  Copyright (C) 2006-2007 Pavel Pisa (ppisa@pikron.com)
+//  Copyright (C) 2008 Juergen Beisert (kernel@pengutronix.de)
+
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/clockchips.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/err.h>
+#include <linux/sched_clock.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <soc/imx/timer.h>
+
+/*
+ * There are 4 versions of the timer hardware on Freescale MXC hardware.
+ *  - MX1/MXL
+ *  - MX21, MX27.
+ *  - MX25, MX31, MX35, MX37, MX51, MX6Q(rev1.0)
+ *  - MX6DL, MX6SX, MX6Q(rev1.1+)
+ */
+
+/* defines common for all i.MX */
+#define MXC_TCTL		0x00
+#define MXC_TCTL_TEN		(1 << 0) /* Enable module */
+#define MXC_TPRER		0x04
+
+/* MX1, MX21, MX27 */
+#define MX1_2_TCTL_CLK_PCLK1	(1 << 1)
+#define MX1_2_TCTL_IRQEN	(1 << 4)
+#define MX1_2_TCTL_FRR		(1 << 8)
+#define MX1_2_TCMP		0x08
+#define MX1_2_TCN		0x10
+#define MX1_2_TSTAT		0x14
+
+/* MX21, MX27 */
+#define MX2_TSTAT_CAPT		(1 << 1)
+#define MX2_TSTAT_COMP		(1 << 0)
+
+/* MX31, MX35, MX25, MX5, MX6 */
+#define V2_TCTL_WAITEN		(1 << 3) /* Wait enable mode */
+#define V2_TCTL_CLK_IPG		(1 << 6)
+#define V2_TCTL_CLK_PER		(2 << 6)
+#define V2_TCTL_CLK_OSC_DIV8	(5 << 6)
+#define V2_TCTL_FRR		(1 << 9)
+#define V2_TCTL_24MEN		(1 << 10)
+#define V2_TPRER_PRE24M		12
+#define V2_IR			0x0c
+#define V2_TSTAT		0x08
+#define V2_TSTAT_OF1		(1 << 0)
+#define V2_TCN			0x24
+#define V2_TCMP			0x10
+
+#define V2_TIMER_RATE_OSC_DIV8	3000000
+
+struct imx_timer {
+	enum imx_gpt_type type;
+	void __iomem *base;
+	int irq;
+	struct clk *clk_per;
+	struct clk *clk_ipg;
+	const struct imx_gpt_data *gpt;
+	struct clock_event_device ced;
+	struct irqaction act;
+};
+
+struct imx_gpt_data {
+	int reg_tstat;
+	int reg_tcn;
+	int reg_tcmp;
+	void (*gpt_setup_tctl)(struct imx_timer *imxtm);
+	void (*gpt_irq_enable)(struct imx_timer *imxtm);
+	void (*gpt_irq_disable)(struct imx_timer *imxtm);
+	void (*gpt_irq_acknowledge)(struct imx_timer *imxtm);
+	int (*set_next_event)(unsigned long evt,
+			      struct clock_event_device *ced);
+};
+
+static inline struct imx_timer *to_imx_timer(struct clock_event_device *ced)
+{
+	return container_of(ced, struct imx_timer, ced);
+}
+
+static void imx1_gpt_irq_disable(struct imx_timer *imxtm)
+{
+	unsigned int tmp;
+
+	tmp = readl_relaxed(imxtm->base + MXC_TCTL);
+	writel_relaxed(tmp & ~MX1_2_TCTL_IRQEN, imxtm->base + MXC_TCTL);
+}
+#define imx21_gpt_irq_disable imx1_gpt_irq_disable
+
+static void imx31_gpt_irq_disable(struct imx_timer *imxtm)
+{
+	writel_relaxed(0, imxtm->base + V2_IR);
+}
+#define imx6dl_gpt_irq_disable imx31_gpt_irq_disable
+
+static void imx1_gpt_irq_enable(struct imx_timer *imxtm)
+{
+	unsigned int tmp;
+
+	tmp = readl_relaxed(imxtm->base + MXC_TCTL);
+	writel_relaxed(tmp | MX1_2_TCTL_IRQEN, imxtm->base + MXC_TCTL);
+}
+#define imx21_gpt_irq_enable imx1_gpt_irq_enable
+
+static void imx31_gpt_irq_enable(struct imx_timer *imxtm)
+{
+	writel_relaxed(1<<0, imxtm->base + V2_IR);
+}
+#define imx6dl_gpt_irq_enable imx31_gpt_irq_enable
+
+static void imx1_gpt_irq_acknowledge(struct imx_timer *imxtm)
+{
+	writel_relaxed(0, imxtm->base + MX1_2_TSTAT);
+}
+
+static void imx21_gpt_irq_acknowledge(struct imx_timer *imxtm)
+{
+	writel_relaxed(MX2_TSTAT_CAPT | MX2_TSTAT_COMP,
+				imxtm->base + MX1_2_TSTAT);
+}
+
+static void imx31_gpt_irq_acknowledge(struct imx_timer *imxtm)
+{
+	writel_relaxed(V2_TSTAT_OF1, imxtm->base + V2_TSTAT);
+}
+#define imx6dl_gpt_irq_acknowledge imx31_gpt_irq_acknowledge
+
+static void __iomem *sched_clock_reg;
+
+static u64 notrace mxc_read_sched_clock(void)
+{
+	return sched_clock_reg ? readl_relaxed(sched_clock_reg) : 0;
+}
+
+static struct delay_timer imx_delay_timer;
+
+static unsigned long imx_read_current_timer(void)
+{
+	return readl_relaxed(sched_clock_reg);
+}
+
+static int __init mxc_clocksource_init(struct imx_timer *imxtm)
+{
+	unsigned int c = clk_get_rate(imxtm->clk_per);
+	void __iomem *reg = imxtm->base + imxtm->gpt->reg_tcn;
+
+	imx_delay_timer.read_current_timer = &imx_read_current_timer;
+	imx_delay_timer.freq = c;
+	register_current_timer_delay(&imx_delay_timer);
+
+	sched_clock_reg = reg;
+
+	sched_clock_register(mxc_read_sched_clock, 32, c);
+	return clocksource_mmio_init(reg, "mxc_timer1", c, 200, 32,
+			clocksource_mmio_readl_up);
+}
+
+/* clock event */
+
+static int mx1_2_set_next_event(unsigned long evt,
+			      struct clock_event_device *ced)
+{
+	struct imx_timer *imxtm = to_imx_timer(ced);
+	unsigned long tcmp;
+
+	tcmp = readl_relaxed(imxtm->base + MX1_2_TCN) + evt;
+
+	writel_relaxed(tcmp, imxtm->base + MX1_2_TCMP);
+
+	return (int)(tcmp - readl_relaxed(imxtm->base + MX1_2_TCN)) < 0 ?
+				-ETIME : 0;
+}
+
+static int v2_set_next_event(unsigned long evt,
+			      struct clock_event_device *ced)
+{
+	struct imx_timer *imxtm = to_imx_timer(ced);
+	unsigned long tcmp;
+
+	tcmp = readl_relaxed(imxtm->base + V2_TCN) + evt;
+
+	writel_relaxed(tcmp, imxtm->base + V2_TCMP);
+
+	return evt < 0x7fffffff &&
+		(int)(tcmp - readl_relaxed(imxtm->base + V2_TCN)) < 0 ?
+				-ETIME : 0;
+}
+
+static int mxc_shutdown(struct clock_event_device *ced)
+{
+	struct imx_timer *imxtm = to_imx_timer(ced);
+	unsigned long flags;
+	u32 tcn;
+
+	/*
+	 * The timer interrupt generation is disabled at least
+	 * for enough time to call mxc_set_next_event()
+	 */
+	local_irq_save(flags);
+
+	/* Disable interrupt in GPT module */
+	imxtm->gpt->gpt_irq_disable(imxtm);
+
+	tcn = readl_relaxed(imxtm->base + imxtm->gpt->reg_tcn);
+	/* Set event time into far-far future */
+	writel_relaxed(tcn - 3, imxtm->base + imxtm->gpt->reg_tcmp);
+
+	/* Clear pending interrupt */
+	imxtm->gpt->gpt_irq_acknowledge(imxtm);
+
+#ifdef DEBUG
+	printk(KERN_INFO "%s: changing mode\n", __func__);
+#endif /* DEBUG */
+
+	local_irq_restore(flags);
+
+	return 0;
+}
+
+static int mxc_set_oneshot(struct clock_event_device *ced)
+{
+	struct imx_timer *imxtm = to_imx_timer(ced);
+	unsigned long flags;
+
+	/*
+	 * The timer interrupt generation is disabled at least
+	 * for enough time to call mxc_set_next_event()
+	 */
+	local_irq_save(flags);
+
+	/* Disable interrupt in GPT module */
+	imxtm->gpt->gpt_irq_disable(imxtm);
+
+	if (!clockevent_state_oneshot(ced)) {
+		u32 tcn = readl_relaxed(imxtm->base + imxtm->gpt->reg_tcn);
+		/* Set event time into far-far future */
+		writel_relaxed(tcn - 3, imxtm->base + imxtm->gpt->reg_tcmp);
+
+		/* Clear pending interrupt */
+		imxtm->gpt->gpt_irq_acknowledge(imxtm);
+	}
+
+#ifdef DEBUG
+	printk(KERN_INFO "%s: changing mode\n", __func__);
+#endif /* DEBUG */
+
+	/*
+	 * Do not put overhead of interrupt enable/disable into
+	 * mxc_set_next_event(), the core has about 4 minutes
+	 * to call mxc_set_next_event() or shutdown clock after
+	 * mode switching
+	 */
+	imxtm->gpt->gpt_irq_enable(imxtm);
+	local_irq_restore(flags);
+
+	return 0;
+}
+
+/*
+ * IRQ handler for the timer
+ */
+static irqreturn_t mxc_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *ced = dev_id;
+	struct imx_timer *imxtm = to_imx_timer(ced);
+	uint32_t tstat;
+
+	tstat = readl_relaxed(imxtm->base + imxtm->gpt->reg_tstat);
+
+	imxtm->gpt->gpt_irq_acknowledge(imxtm);
+
+	ced->event_handler(ced);
+
+	return IRQ_HANDLED;
+}
+
+static int __init mxc_clockevent_init(struct imx_timer *imxtm)
+{
+	struct clock_event_device *ced = &imxtm->ced;
+	struct irqaction *act = &imxtm->act;
+
+	ced->name = "mxc_timer1";
+	ced->features = CLOCK_EVT_FEAT_ONESHOT | CLOCK_EVT_FEAT_DYNIRQ;
+	ced->set_state_shutdown = mxc_shutdown;
+	ced->set_state_oneshot = mxc_set_oneshot;
+	ced->tick_resume = mxc_shutdown;
+	ced->set_next_event = imxtm->gpt->set_next_event;
+	ced->rating = 200;
+	ced->cpumask = cpumask_of(0);
+	ced->irq = imxtm->irq;
+	clockevents_config_and_register(ced, clk_get_rate(imxtm->clk_per),
+					0xff, 0xfffffffe);
+
+	act->name = "i.MX Timer Tick";
+	act->flags = IRQF_TIMER | IRQF_IRQPOLL;
+	act->handler = mxc_timer_interrupt;
+	act->dev_id = ced;
+
+	return setup_irq(imxtm->irq, act);
+}
+
+static void imx1_gpt_setup_tctl(struct imx_timer *imxtm)
+{
+	u32 tctl_val;
+
+	tctl_val = MX1_2_TCTL_FRR | MX1_2_TCTL_CLK_PCLK1 | MXC_TCTL_TEN;
+	writel_relaxed(tctl_val, imxtm->base + MXC_TCTL);
+}
+#define imx21_gpt_setup_tctl imx1_gpt_setup_tctl
+
+static void imx31_gpt_setup_tctl(struct imx_timer *imxtm)
+{
+	u32 tctl_val;
+
+	tctl_val = V2_TCTL_FRR | V2_TCTL_WAITEN | MXC_TCTL_TEN;
+	if (clk_get_rate(imxtm->clk_per) == V2_TIMER_RATE_OSC_DIV8)
+		tctl_val |= V2_TCTL_CLK_OSC_DIV8;
+	else
+		tctl_val |= V2_TCTL_CLK_PER;
+
+	writel_relaxed(tctl_val, imxtm->base + MXC_TCTL);
+}
+
+static void imx6dl_gpt_setup_tctl(struct imx_timer *imxtm)
+{
+	u32 tctl_val;
+
+	tctl_val = V2_TCTL_FRR | V2_TCTL_WAITEN | MXC_TCTL_TEN;
+	if (clk_get_rate(imxtm->clk_per) == V2_TIMER_RATE_OSC_DIV8) {
+		tctl_val |= V2_TCTL_CLK_OSC_DIV8;
+		/* 24 / 8 = 3 MHz */
+		writel_relaxed(7 << V2_TPRER_PRE24M, imxtm->base + MXC_TPRER);
+		tctl_val |= V2_TCTL_24MEN;
+	} else {
+		tctl_val |= V2_TCTL_CLK_PER;
+	}
+
+	writel_relaxed(tctl_val, imxtm->base + MXC_TCTL);
+}
+
+static const struct imx_gpt_data imx1_gpt_data = {
+	.reg_tstat = MX1_2_TSTAT,
+	.reg_tcn = MX1_2_TCN,
+	.reg_tcmp = MX1_2_TCMP,
+	.gpt_irq_enable = imx1_gpt_irq_enable,
+	.gpt_irq_disable = imx1_gpt_irq_disable,
+	.gpt_irq_acknowledge = imx1_gpt_irq_acknowledge,
+	.gpt_setup_tctl = imx1_gpt_setup_tctl,
+	.set_next_event = mx1_2_set_next_event,
+};
+
+static const struct imx_gpt_data imx21_gpt_data = {
+	.reg_tstat = MX1_2_TSTAT,
+	.reg_tcn = MX1_2_TCN,
+	.reg_tcmp = MX1_2_TCMP,
+	.gpt_irq_enable = imx21_gpt_irq_enable,
+	.gpt_irq_disable = imx21_gpt_irq_disable,
+	.gpt_irq_acknowledge = imx21_gpt_irq_acknowledge,
+	.gpt_setup_tctl = imx21_gpt_setup_tctl,
+	.set_next_event = mx1_2_set_next_event,
+};
+
+static const struct imx_gpt_data imx31_gpt_data = {
+	.reg_tstat = V2_TSTAT,
+	.reg_tcn = V2_TCN,
+	.reg_tcmp = V2_TCMP,
+	.gpt_irq_enable = imx31_gpt_irq_enable,
+	.gpt_irq_disable = imx31_gpt_irq_disable,
+	.gpt_irq_acknowledge = imx31_gpt_irq_acknowledge,
+	.gpt_setup_tctl = imx31_gpt_setup_tctl,
+	.set_next_event = v2_set_next_event,
+};
+
+static const struct imx_gpt_data imx6dl_gpt_data = {
+	.reg_tstat = V2_TSTAT,
+	.reg_tcn = V2_TCN,
+	.reg_tcmp = V2_TCMP,
+	.gpt_irq_enable = imx6dl_gpt_irq_enable,
+	.gpt_irq_disable = imx6dl_gpt_irq_disable,
+	.gpt_irq_acknowledge = imx6dl_gpt_irq_acknowledge,
+	.gpt_setup_tctl = imx6dl_gpt_setup_tctl,
+	.set_next_event = v2_set_next_event,
+};
+
+static int __init _mxc_timer_init(struct imx_timer *imxtm)
+{
+	int ret;
+
+	switch (imxtm->type) {
+	case GPT_TYPE_IMX1:
+		imxtm->gpt = &imx1_gpt_data;
+		break;
+	case GPT_TYPE_IMX21:
+		imxtm->gpt = &imx21_gpt_data;
+		break;
+	case GPT_TYPE_IMX31:
+		imxtm->gpt = &imx31_gpt_data;
+		break;
+	case GPT_TYPE_IMX6DL:
+		imxtm->gpt = &imx6dl_gpt_data;
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (IS_ERR(imxtm->clk_per)) {
+		pr_err("i.MX timer: unable to get clk\n");
+		return PTR_ERR(imxtm->clk_per);
+	}
+
+	if (!IS_ERR(imxtm->clk_ipg))
+		clk_prepare_enable(imxtm->clk_ipg);
+
+	clk_prepare_enable(imxtm->clk_per);
+
+	/*
+	 * Initialise to a known state (all timers off, and timing reset)
+	 */
+
+	writel_relaxed(0, imxtm->base + MXC_TCTL);
+	writel_relaxed(0, imxtm->base + MXC_TPRER); /* see datasheet note */
+
+	imxtm->gpt->gpt_setup_tctl(imxtm);
+
+	/* init and register the timer to the framework */
+	ret = mxc_clocksource_init(imxtm);
+	if (ret)
+		return ret;
+
+	return mxc_clockevent_init(imxtm);
+}
+
+void __init mxc_timer_init(unsigned long pbase, int irq, enum imx_gpt_type type)
+{
+	struct imx_timer *imxtm;
+
+	imxtm = kzalloc(sizeof(*imxtm), GFP_KERNEL);
+	BUG_ON(!imxtm);
+
+	imxtm->clk_per = clk_get_sys("imx-gpt.0", "per");
+	imxtm->clk_ipg = clk_get_sys("imx-gpt.0", "ipg");
+
+	imxtm->base = ioremap(pbase, SZ_4K);
+	BUG_ON(!imxtm->base);
+
+	imxtm->type = type;
+	imxtm->irq = irq;
+
+	_mxc_timer_init(imxtm);
+}
+
+static int __init mxc_timer_init_dt(struct device_node *np,  enum imx_gpt_type type)
+{
+	struct imx_timer *imxtm;
+	static int initialized;
+	int ret;
+
+	/* Support one instance only */
+	if (initialized)
+		return 0;
+
+	imxtm = kzalloc(sizeof(*imxtm), GFP_KERNEL);
+	if (!imxtm)
+		return -ENOMEM;
+
+	imxtm->base = of_iomap(np, 0);
+	if (!imxtm->base)
+		return -ENXIO;
+
+	imxtm->irq = irq_of_parse_and_map(np, 0);
+	if (imxtm->irq <= 0)
+		return -EINVAL;
+
+	imxtm->clk_ipg = of_clk_get_by_name(np, "ipg");
+
+	/* Try osc_per first, and fall back to per otherwise */
+	imxtm->clk_per = of_clk_get_by_name(np, "osc_per");
+	if (IS_ERR(imxtm->clk_per))
+		imxtm->clk_per = of_clk_get_by_name(np, "per");
+
+	imxtm->type = type;
+
+	ret = _mxc_timer_init(imxtm);
+	if (ret)
+		return ret;
+
+	initialized = 1;
+
+	return 0;
+}
+
+static int __init imx1_timer_init_dt(struct device_node *np)
+{
+	return mxc_timer_init_dt(np, GPT_TYPE_IMX1);
+}
+
+static int __init imx21_timer_init_dt(struct device_node *np)
+{
+	return mxc_timer_init_dt(np, GPT_TYPE_IMX21);
+}
+
+static int __init imx31_timer_init_dt(struct device_node *np)
+{
+	enum imx_gpt_type type = GPT_TYPE_IMX31;
+
+	/*
+	 * We were using the same compatible string for i.MX6Q/D and i.MX6DL/S
+	 * GPT device, while they actually have different programming model.
+	 * This is a workaround to keep the existing i.MX6DL/S DTBs continue
+	 * working with the new kernel.
+	 */
+	if (of_machine_is_compatible("fsl,imx6dl"))
+		type = GPT_TYPE_IMX6DL;
+
+	return mxc_timer_init_dt(np, type);
+}
+
+static int __init imx6dl_timer_init_dt(struct device_node *np)
+{
+	return mxc_timer_init_dt(np, GPT_TYPE_IMX6DL);
+}
+
+TIMER_OF_DECLARE(imx1_timer, "fsl,imx1-gpt", imx1_timer_init_dt);
+TIMER_OF_DECLARE(imx21_timer, "fsl,imx21-gpt", imx21_timer_init_dt);
+TIMER_OF_DECLARE(imx27_timer, "fsl,imx27-gpt", imx21_timer_init_dt);
+TIMER_OF_DECLARE(imx31_timer, "fsl,imx31-gpt", imx31_timer_init_dt);
+TIMER_OF_DECLARE(imx25_timer, "fsl,imx25-gpt", imx31_timer_init_dt);
+TIMER_OF_DECLARE(imx50_timer, "fsl,imx50-gpt", imx31_timer_init_dt);
+TIMER_OF_DECLARE(imx51_timer, "fsl,imx51-gpt", imx31_timer_init_dt);
+TIMER_OF_DECLARE(imx53_timer, "fsl,imx53-gpt", imx31_timer_init_dt);
+TIMER_OF_DECLARE(imx6q_timer, "fsl,imx6q-gpt", imx31_timer_init_dt);
+TIMER_OF_DECLARE(imx6dl_timer, "fsl,imx6dl-gpt", imx6dl_timer_init_dt);
+TIMER_OF_DECLARE(imx6sl_timer, "fsl,imx6sl-gpt", imx6dl_timer_init_dt);
+TIMER_OF_DECLARE(imx6sx_timer, "fsl,imx6sx-gpt", imx6dl_timer_init_dt);

drivers/clocksource/timer-imx-tpm.c

@@ -0,0 +1,257 @@
+// SPDX-License-Identifier: GPL-2.0+
+//
+// Copyright 2016 Freescale Semiconductor, Inc.
+// Copyright 2017 NXP
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+
+#define TPM_PARAM			0x4
+#define TPM_PARAM_WIDTH_SHIFT		16
+#define TPM_PARAM_WIDTH_MASK		(0xff << 16)
+#define TPM_SC				0x10
+#define TPM_SC_CMOD_INC_PER_CNT		(0x1 << 3)
+#define TPM_SC_CMOD_DIV_DEFAULT		0x3
+#define TPM_SC_CMOD_DIV_MAX		0x7
+#define TPM_SC_TOF_MASK			(0x1 << 7)
+#define TPM_CNT				0x14
+#define TPM_MOD				0x18
+#define TPM_STATUS			0x1c
+#define TPM_STATUS_CH0F			BIT(0)
+#define TPM_C0SC			0x20
+#define TPM_C0SC_CHIE			BIT(6)
+#define TPM_C0SC_MODE_SHIFT		2
+#define TPM_C0SC_MODE_MASK		0x3c
+#define TPM_C0SC_MODE_SW_COMPARE	0x4
+#define TPM_C0SC_CHF_MASK		(0x1 << 7)
+#define TPM_C0V				0x24
+
+static int counter_width;
+static int rating;
+static void __iomem *timer_base;
+static struct clock_event_device clockevent_tpm;
+
+static inline void tpm_timer_disable(void)
+{
+	unsigned int val;
+
+	/* channel disable */
+	val = readl(timer_base + TPM_C0SC);
+	val &= ~(TPM_C0SC_MODE_MASK | TPM_C0SC_CHIE);
+	writel(val, timer_base + TPM_C0SC);
+}
+
+static inline void tpm_timer_enable(void)
+{
+	unsigned int val;
+
+	/* channel enabled in sw compare mode */
+	val = readl(timer_base + TPM_C0SC);
+	val |= (TPM_C0SC_MODE_SW_COMPARE << TPM_C0SC_MODE_SHIFT) |
+	       TPM_C0SC_CHIE;
+	writel(val, timer_base + TPM_C0SC);
+}
+
+static inline void tpm_irq_acknowledge(void)
+{
+	writel(TPM_STATUS_CH0F, timer_base + TPM_STATUS);
+}
+
+static struct delay_timer tpm_delay_timer;
+
+static inline unsigned long tpm_read_counter(void)
+{
+	return readl(timer_base + TPM_CNT);
+}
+
+static unsigned long tpm_read_current_timer(void)
+{
+	return tpm_read_counter();
+}
+
+static u64 notrace tpm_read_sched_clock(void)
+{
+	return tpm_read_counter();
+}
+
+static int __init tpm_clocksource_init(unsigned long rate)
+{
+	tpm_delay_timer.read_current_timer = &tpm_read_current_timer;
+	tpm_delay_timer.freq = rate;
+	register_current_timer_delay(&tpm_delay_timer);
+
+	sched_clock_register(tpm_read_sched_clock, counter_width, rate);
+
+	return clocksource_mmio_init(timer_base + TPM_CNT, "imx-tpm",
+				     rate, rating, counter_width,
+				     clocksource_mmio_readl_up);
+}
+
+static int tpm_set_next_event(unsigned long delta,
+				struct clock_event_device *evt)
+{
+	unsigned long next, now;
+
+	next = tpm_read_counter();
+	next += delta;
+	writel(next, timer_base + TPM_C0V);
+	now = tpm_read_counter();
+
+	/*
+	 * NOTE: We observed in a very small probability, the bus fabric
+	 * contention between GPU and A7 may results a few cycles delay
+	 * of writing CNT registers which may cause the min_delta event got
+	 * missed, so we need add a ETIME check here in case it happened.
+	 */
+	return (int)(next - now) <= 0 ? -ETIME : 0;
+}
+
+static int tpm_set_state_oneshot(struct clock_event_device *evt)
+{
+	tpm_timer_enable();
+
+	return 0;
+}
+
+static int tpm_set_state_shutdown(struct clock_event_device *evt)
+{
+	tpm_timer_disable();
+
+	return 0;
+}
+
+static irqreturn_t tpm_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	tpm_irq_acknowledge();
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static struct clock_event_device clockevent_tpm = {
+	.name			= "i.MX7ULP TPM Timer",
+	.features		= CLOCK_EVT_FEAT_ONESHOT,
+	.set_state_oneshot	= tpm_set_state_oneshot,
+	.set_next_event		= tpm_set_next_event,
+	.set_state_shutdown	= tpm_set_state_shutdown,
+};
+
+static int __init tpm_clockevent_init(unsigned long rate, int irq)
+{
+	int ret;
+
+	ret = request_irq(irq, tpm_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
+			  "i.MX7ULP TPM Timer", &clockevent_tpm);
+
+	clockevent_tpm.rating = rating;
+	clockevent_tpm.cpumask = cpumask_of(0);
+	clockevent_tpm.irq = irq;
+	clockevents_config_and_register(&clockevent_tpm, rate, 300,
+					GENMASK(counter_width - 1, 1));
+
+	return ret;
+}
+
+static int __init tpm_timer_init(struct device_node *np)
+{
+	struct clk *ipg, *per;
+	int irq, ret;
+	u32 rate;
+
+	timer_base = of_iomap(np, 0);
+	if (!timer_base) {
+		pr_err("tpm: failed to get base address\n");
+		return -ENXIO;
+	}
+
+	irq = irq_of_parse_and_map(np, 0);
+	if (!irq) {
+		pr_err("tpm: failed to get irq\n");
+		ret = -ENOENT;
+		goto err_iomap;
+	}
+
+	ipg = of_clk_get_by_name(np, "ipg");
+	per = of_clk_get_by_name(np, "per");
+	if (IS_ERR(ipg) || IS_ERR(per)) {
+		pr_err("tpm: failed to get ipg or per clk\n");
+		ret = -ENODEV;
+		goto err_clk_get;
+	}
+
+	/* enable clk before accessing registers */
+	ret = clk_prepare_enable(ipg);
+	if (ret) {
+		pr_err("tpm: ipg clock enable failed (%d)\n", ret);
+		goto err_clk_get;
+	}
+
+	ret = clk_prepare_enable(per);
+	if (ret) {
+		pr_err("tpm: per clock enable failed (%d)\n", ret);
+		goto err_per_clk_enable;
+	}
+
+	counter_width = (readl(timer_base + TPM_PARAM) & TPM_PARAM_WIDTH_MASK)
+		>> TPM_PARAM_WIDTH_SHIFT;
+	/* use rating 200 for 32-bit counter and 150 for 16-bit counter */
+	rating = counter_width == 0x20 ? 200 : 150;
+
+	/*
+	 * Initialize tpm module to a known state
+	 * 1) Counter disabled
+	 * 2) TPM counter operates in up counting mode
+	 * 3) Timer Overflow Interrupt disabled
+	 * 4) Channel0 disabled
+	 * 5) DMA transfers disabled
+	 */
+	/* make sure counter is disabled */
+	writel(0, timer_base + TPM_SC);
+	/* TOF is W1C */
+	writel(TPM_SC_TOF_MASK, timer_base + TPM_SC);
+	writel(0, timer_base + TPM_CNT);
+	/* CHF is W1C */
+	writel(TPM_C0SC_CHF_MASK, timer_base + TPM_C0SC);
+
+	/*
+	 * increase per cnt,
+	 * div 8 for 32-bit counter and div 128 for 16-bit counter
+	 */
+	writel(TPM_SC_CMOD_INC_PER_CNT |
+		(counter_width == 0x20 ?
+		TPM_SC_CMOD_DIV_DEFAULT : TPM_SC_CMOD_DIV_MAX),
+		     timer_base + TPM_SC);
+
+	/* set MOD register to maximum for free running mode */
+	writel(GENMASK(counter_width - 1, 0), timer_base + TPM_MOD);
+
+	rate = clk_get_rate(per) >> 3;
+	ret = tpm_clocksource_init(rate);
+	if (ret)
+		goto err_per_clk_enable;
+
+	ret = tpm_clockevent_init(rate, irq);
+	if (ret)
+		goto err_per_clk_enable;
+
+	return 0;
+
+err_per_clk_enable:
+	clk_disable_unprepare(ipg);
+err_clk_get:
+	clk_put(per);
+	clk_put(ipg);
+err_iomap:
+	iounmap(timer_base);
+	return ret;
+}
+TIMER_OF_DECLARE(imx7ulp, "fsl,imx7ulp-tpm", tpm_timer_init);

drivers/clocksource/timer-integrator-ap.c

@@ -0,0 +1,243 @@
+/*
+ * Integrator/AP timer driver
+ * Copyright (C) 2000-2003 Deep Blue Solutions Ltd
+ * Copyright (c) 2014, Linaro Limited
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+#include <linux/clk.h>
+#include <linux/clocksource.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/of_platform.h>
+#include <linux/clockchips.h>
+#include <linux/interrupt.h>
+#include <linux/sched_clock.h>
+
+#include "timer-sp.h"
+
+static void __iomem * sched_clk_base;
+
+static u64 notrace integrator_read_sched_clock(void)
+{
+	return -readl(sched_clk_base + TIMER_VALUE);
+}
+
+static int __init integrator_clocksource_init(unsigned long inrate,
+					      void __iomem *base)
+{
+	u32 ctrl = TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC;
+	unsigned long rate = inrate;
+	int ret;
+
+	if (rate >= 1500000) {
+		rate /= 16;
+		ctrl |= TIMER_CTRL_DIV16;
+	}
+
+	writel(0xffff, base + TIMER_LOAD);
+	writel(ctrl, base + TIMER_CTRL);
+
+	ret = clocksource_mmio_init(base + TIMER_VALUE, "timer2",
+				    rate, 200, 16, clocksource_mmio_readl_down);
+	if (ret)
+		return ret;
+
+	sched_clk_base = base;
+	sched_clock_register(integrator_read_sched_clock, 16, rate);
+
+	return 0;
+}
+
+static unsigned long timer_reload;
+static void __iomem * clkevt_base;
+
+/*
+ * IRQ handler for the timer
+ */
+static irqreturn_t integrator_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	/* clear the interrupt */
+	writel(1, clkevt_base + TIMER_INTCLR);
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static int clkevt_shutdown(struct clock_event_device *evt)
+{
+	u32 ctrl = readl(clkevt_base + TIMER_CTRL) & ~TIMER_CTRL_ENABLE;
+
+	/* Disable timer */
+	writel(ctrl, clkevt_base + TIMER_CTRL);
+	return 0;
+}
+
+static int clkevt_set_oneshot(struct clock_event_device *evt)
+{
+	u32 ctrl = readl(clkevt_base + TIMER_CTRL) &
+		   ~(TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC);
+
+	/* Leave the timer disabled, .set_next_event will enable it */
+	writel(ctrl, clkevt_base + TIMER_CTRL);
+	return 0;
+}
+
+static int clkevt_set_periodic(struct clock_event_device *evt)
+{
+	u32 ctrl = readl(clkevt_base + TIMER_CTRL) & ~TIMER_CTRL_ENABLE;
+
+	/* Disable timer */
+	writel(ctrl, clkevt_base + TIMER_CTRL);
+
+	/* Enable the timer and start the periodic tick */
+	writel(timer_reload, clkevt_base + TIMER_LOAD);
+	ctrl |= TIMER_CTRL_PERIODIC | TIMER_CTRL_ENABLE;
+	writel(ctrl, clkevt_base + TIMER_CTRL);
+	return 0;
+}
+
+static int clkevt_set_next_event(unsigned long next, struct clock_event_device *evt)
+{
+	unsigned long ctrl = readl(clkevt_base + TIMER_CTRL);
+
+	writel(ctrl & ~TIMER_CTRL_ENABLE, clkevt_base + TIMER_CTRL);
+	writel(next, clkevt_base + TIMER_LOAD);
+	writel(ctrl | TIMER_CTRL_ENABLE, clkevt_base + TIMER_CTRL);
+
+	return 0;
+}
+
+static struct clock_event_device integrator_clockevent = {
+	.name			= "timer1",
+	.features		= CLOCK_EVT_FEAT_PERIODIC |
+				  CLOCK_EVT_FEAT_ONESHOT,
+	.set_state_shutdown	= clkevt_shutdown,
+	.set_state_periodic	= clkevt_set_periodic,
+	.set_state_oneshot	= clkevt_set_oneshot,
+	.tick_resume		= clkevt_shutdown,
+	.set_next_event		= clkevt_set_next_event,
+	.rating			= 300,
+};
+
+static struct irqaction integrator_timer_irq = {
+	.name		= "timer",
+	.flags		= IRQF_TIMER | IRQF_IRQPOLL,
+	.handler	= integrator_timer_interrupt,
+	.dev_id		= &integrator_clockevent,
+};
+
+static int integrator_clockevent_init(unsigned long inrate,
+				      void __iomem *base, int irq)
+{
+	unsigned long rate = inrate;
+	unsigned int ctrl = 0;
+	int ret;
+
+	clkevt_base = base;
+	/* Calculate and program a divisor */
+	if (rate > 0x100000 * HZ) {
+		rate /= 256;
+		ctrl |= TIMER_CTRL_DIV256;
+	} else if (rate > 0x10000 * HZ) {
+		rate /= 16;
+		ctrl |= TIMER_CTRL_DIV16;
+	}
+	timer_reload = rate / HZ;
+	writel(ctrl, clkevt_base + TIMER_CTRL);
+
+	ret = setup_irq(irq, &integrator_timer_irq);
+	if (ret)
+		return ret;
+
+	clockevents_config_and_register(&integrator_clockevent,
+					rate,
+					1,
+					0xffffU);
+	return 0;
+}
+
+static int __init integrator_ap_timer_init_of(struct device_node *node)
+{
+	const char *path;
+	void __iomem *base;
+	int err;
+	int irq;
+	struct clk *clk;
+	unsigned long rate;
+	struct device_node *alias_node;
+
+	base = of_io_request_and_map(node, 0, "integrator-timer");
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	clk = of_clk_get(node, 0);
+	if (IS_ERR(clk)) {
+		pr_err("No clock for %s\n", node->name);
+		return PTR_ERR(clk);
+	}
+	clk_prepare_enable(clk);
+	rate = clk_get_rate(clk);
+	writel(0, base + TIMER_CTRL);
+
+	err = of_property_read_string(of_aliases,
+				"arm,timer-primary", &path);
+	if (err) {
+		pr_warn("Failed to read property\n");
+		return err;
+	}
+
+	alias_node = of_find_node_by_path(path);
+
+	/*
+	 * The pointer is used as an identifier not as a pointer, we
+	 * can drop the refcount on the of__node immediately after
+	 * getting it.
+	 */
+	of_node_put(alias_node);
+
+	if (node == alias_node)
+		/* The primary timer lacks IRQ, use as clocksource */
+		return integrator_clocksource_init(rate, base);
+
+	err = of_property_read_string(of_aliases,
+				"arm,timer-secondary", &path);
+	if (err) {
+		pr_warn("Failed to read property\n");
+		return err;
+	}
+
+	alias_node = of_find_node_by_path(path);
+
+	of_node_put(alias_node);
+
+	if (node == alias_node) {
+		/* The secondary timer will drive the clock event */
+		irq = irq_of_parse_and_map(node, 0);
+		return integrator_clockevent_init(rate, base, irq);
+	}
+
+	pr_info("Timer @%p unused\n", base);
+	clk_disable_unprepare(clk);
+
+	return 0;
+}
+
+TIMER_OF_DECLARE(integrator_ap_timer, "arm,integrator-timer",
+		       integrator_ap_timer_init_of);

drivers/clocksource/timer-keystone.c

@@ -0,0 +1,230 @@
+/*
+ * Keystone broadcast clock-event
+ *
+ * Copyright 2013 Texas Instruments, Inc.
+ *
+ * Author: Ivan Khoronzhuk <ivan.khoronzhuk@ti.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/interrupt.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define TIMER_NAME			"timer-keystone"
+
+/* Timer register offsets */
+#define TIM12				0x10
+#define TIM34				0x14
+#define PRD12				0x18
+#define PRD34				0x1c
+#define TCR				0x20
+#define TGCR				0x24
+#define INTCTLSTAT			0x44
+
+/* Timer register bitfields */
+#define TCR_ENAMODE_MASK		0xC0
+#define TCR_ENAMODE_ONESHOT_MASK	0x40
+#define TCR_ENAMODE_PERIODIC_MASK	0x80
+
+#define TGCR_TIM_UNRESET_MASK		0x03
+#define INTCTLSTAT_ENINT_MASK		0x01
+
+/**
+ * struct keystone_timer: holds timer's data
+ * @base: timer memory base address
+ * @hz_period: cycles per HZ period
+ * @event_dev: event device based on timer
+ */
+static struct keystone_timer {
+	void __iomem *base;
+	unsigned long hz_period;
+	struct clock_event_device event_dev;
+} timer;
+
+static inline u32 keystone_timer_readl(unsigned long rg)
+{
+	return readl_relaxed(timer.base + rg);
+}
+
+static inline void keystone_timer_writel(u32 val, unsigned long rg)
+{
+	writel_relaxed(val, timer.base + rg);
+}
+
+/**
+ * keystone_timer_barrier: write memory barrier
+ * use explicit barrier to avoid using readl/writel non relaxed function
+ * variants, because in our case non relaxed variants hide the true places
+ * where barrier is needed.
+ */
+static inline void keystone_timer_barrier(void)
+{
+	__iowmb();
+}
+
+/**
+ * keystone_timer_config: configures timer to work in oneshot/periodic modes.
+ * @ mask: mask of the mode to configure
+ * @ period: cycles number to configure for
+ */
+static int keystone_timer_config(u64 period, int mask)
+{
+	u32 tcr;
+	u32 off;
+
+	tcr = keystone_timer_readl(TCR);
+	off = tcr & ~(TCR_ENAMODE_MASK);
+
+	/* set enable mode */
+	tcr |= mask;
+
+	/* disable timer */
+	keystone_timer_writel(off, TCR);
+	/* here we have to be sure the timer has been disabled */
+	keystone_timer_barrier();
+
+	/* reset counter to zero, set new period */
+	keystone_timer_writel(0, TIM12);
+	keystone_timer_writel(0, TIM34);
+	keystone_timer_writel(period & 0xffffffff, PRD12);
+	keystone_timer_writel(period >> 32, PRD34);
+
+	/*
+	 * enable timer
+	 * here we have to be sure that CNTLO, CNTHI, PRDLO, PRDHI registers
+	 * have been written.
+	 */
+	keystone_timer_barrier();
+	keystone_timer_writel(tcr, TCR);
+	return 0;
+}
+
+static void keystone_timer_disable(void)
+{
+	u32 tcr;
+
+	tcr = keystone_timer_readl(TCR);
+
+	/* disable timer */
+	tcr &= ~(TCR_ENAMODE_MASK);
+	keystone_timer_writel(tcr, TCR);
+}
+
+static irqreturn_t keystone_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	evt->event_handler(evt);
+	return IRQ_HANDLED;
+}
+
+static int keystone_set_next_event(unsigned long cycles,
+				  struct clock_event_device *evt)
+{
+	return keystone_timer_config(cycles, TCR_ENAMODE_ONESHOT_MASK);
+}
+
+static int keystone_shutdown(struct clock_event_device *evt)
+{
+	keystone_timer_disable();
+	return 0;
+}
+
+static int keystone_set_periodic(struct clock_event_device *evt)
+{
+	keystone_timer_config(timer.hz_period, TCR_ENAMODE_PERIODIC_MASK);
+	return 0;
+}
+
+static int __init keystone_timer_init(struct device_node *np)
+{
+	struct clock_event_device *event_dev = &timer.event_dev;
+	unsigned long rate;
+	struct clk *clk;
+	int irq, error;
+
+	irq  = irq_of_parse_and_map(np, 0);
+	if (!irq) {
+		pr_err("%s: failed to map interrupts\n", __func__);
+		return -EINVAL;
+	}
+
+	timer.base = of_iomap(np, 0);
+	if (!timer.base) {
+		pr_err("%s: failed to map registers\n", __func__);
+		return -ENXIO;
+	}
+
+	clk = of_clk_get(np, 0);
+	if (IS_ERR(clk)) {
+		pr_err("%s: failed to get clock\n", __func__);
+		iounmap(timer.base);
+		return PTR_ERR(clk);
+	}
+
+	error = clk_prepare_enable(clk);
+	if (error) {
+		pr_err("%s: failed to enable clock\n", __func__);
+		goto err;
+	}
+
+	rate = clk_get_rate(clk);
+
+	/* disable, use internal clock source */
+	keystone_timer_writel(0, TCR);
+	/* here we have to be sure the timer has been disabled */
+	keystone_timer_barrier();
+
+	/* reset timer as 64-bit, no pre-scaler, plus features are disabled */
+	keystone_timer_writel(0, TGCR);
+
+	/* unreset timer */
+	keystone_timer_writel(TGCR_TIM_UNRESET_MASK, TGCR);
+
+	/* init counter to zero */
+	keystone_timer_writel(0, TIM12);
+	keystone_timer_writel(0, TIM34);
+
+	timer.hz_period = DIV_ROUND_UP(rate, HZ);
+
+	/* enable timer interrupts */
+	keystone_timer_writel(INTCTLSTAT_ENINT_MASK, INTCTLSTAT);
+
+	error = request_irq(irq, keystone_timer_interrupt, IRQF_TIMER,
+			    TIMER_NAME, event_dev);
+	if (error) {
+		pr_err("%s: failed to setup irq\n", __func__);
+		goto err;
+	}
+
+	/* setup clockevent */
+	event_dev->features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
+	event_dev->set_next_event = keystone_set_next_event;
+	event_dev->set_state_shutdown = keystone_shutdown;
+	event_dev->set_state_periodic = keystone_set_periodic;
+	event_dev->set_state_oneshot = keystone_shutdown;
+	event_dev->cpumask = cpu_possible_mask;
+	event_dev->owner = THIS_MODULE;
+	event_dev->name = TIMER_NAME;
+	event_dev->irq = irq;
+
+	clockevents_config_and_register(event_dev, rate, 1, ULONG_MAX);
+
+	pr_info("keystone timer clock @%lu Hz\n", rate);
+	return 0;
+err:
+	clk_put(clk);
+	iounmap(timer.base);
+	return error;
+}
+
+TIMER_OF_DECLARE(keystone_timer, "ti,keystone-timer",
+			   keystone_timer_init);

drivers/clocksource/timer-mediatek.c

@@ -0,0 +1,422 @@
+/*
+ * Mediatek SoCs General-Purpose Timer handling.
+ *
+ * Copyright (C) 2014 Matthias Brugger
+ *
+ * Matthias Brugger <matthias.bgg@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/interrupt.h>
+#include <linux/irqreturn.h>
+#include <linux/of.h>
+#include <linux/sched_clock.h>
+#include <linux/slab.h>
+#include "timer-of.h"
+
+#define TIMER_CLK_EVT           (1)
+#define TIMER_CLK_SRC           (2)
+
+#define TIMER_SYNC_TICKS        (3)
+
+/* gpt */
+#define GPT_IRQ_EN_REG          0x00
+#define GPT_IRQ_ENABLE(val)     BIT((val) - 1)
+#define GPT_IRQ_ACK_REG	        0x08
+#define GPT_IRQ_ACK(val)        BIT((val) - 1)
+
+#define GPT_CTRL_REG(val)       (0x10 * (val))
+#define GPT_CTRL_OP(val)        (((val) & 0x3) << 4)
+#define GPT_CTRL_OP_ONESHOT     (0)
+#define GPT_CTRL_OP_REPEAT      (1)
+#define GPT_CTRL_OP_FREERUN     (3)
+#define GPT_CTRL_CLEAR          (2)
+#define GPT_CTRL_ENABLE         (1)
+#define GPT_CTRL_DISABLE        (0)
+
+#define GPT_CLK_REG(val)        (0x04 + (0x10 * (val)))
+#define GPT_CLK_SRC(val)        (((val) & 0x1) << 4)
+#define GPT_CLK_SRC_SYS13M      (0)
+#define GPT_CLK_SRC_RTC32K      (1)
+#define GPT_CLK_DIV1            (0x0)
+#define GPT_CLK_DIV2            (0x1)
+
+#define GPT_CNT_REG(val)        (0x08 + (0x10 * (val)))
+#define GPT_CMP_REG(val)        (0x0C + (0x10 * (val)))
+
+/* system timer */
+#define SYST_BASE               (0x40)
+
+#define SYST_CON                (SYST_BASE + 0x0)
+#define SYST_VAL                (SYST_BASE + 0x4)
+
+#define SYST_CON_REG(to)        (timer_of_base(to) + SYST_CON)
+#define SYST_VAL_REG(to)        (timer_of_base(to) + SYST_VAL)
+
+/*
+ * SYST_CON_EN: Clock enable. Shall be set to
+ *   - Start timer countdown.
+ *   - Allow timeout ticks being updated.
+ *   - Allow changing interrupt functions.
+ *
+ * SYST_CON_IRQ_EN: Set to allow interrupt.
+ *
+ * SYST_CON_IRQ_CLR: Set to clear interrupt.
+ */
+#define SYST_CON_EN              BIT(0)
+#define SYST_CON_IRQ_EN          BIT(1)
+#define SYST_CON_IRQ_CLR         BIT(4)
+
+#ifdef CONFIG_MTK_AEE_IPANIC
+#define SYST_DEBUG
+#endif
+
+#ifdef SYST_DEBUG
+#include <linux/sched/clock.h>
+#include <mt-plat/mboot_params.h>
+
+static char         dbg_buf[128];
+static unsigned int dbg_setevt_cpu;
+static uint64_t     t_setevt_in;
+static uint64_t     t_hdl_in;
+static uint64_t     t_setevt_ticks;
+
+#define aee_log(fmt, ...) \
+do { \
+	memset(dbg_buf, 0, sizeof(dbg_buf)); \
+	if (snprintf(dbg_buf, sizeof(dbg_buf), fmt, ##__VA_ARGS__) > 0) \
+		aee_sram_fiq_log(dbg_buf); \
+} while (0)
+#endif
+
+static void __iomem *gpt_sched_reg __read_mostly;
+
+static void mtk_syst_ack_irq(struct timer_of *to)
+{
+	/* Clear and disable interrupt */
+	writel(SYST_CON_IRQ_CLR | SYST_CON_EN, SYST_CON_REG(to));
+}
+
+static irqreturn_t mtk_syst_handler(int irq, void *dev_id)
+{
+	struct clock_event_device *clkevt = dev_id;
+	struct timer_of *to = to_timer_of(clkevt);
+
+#ifdef SYST_DEBUG
+	t_hdl_in = sched_clock();
+#endif
+	mtk_syst_ack_irq(to);
+	clkevt->event_handler(clkevt);
+
+	return IRQ_HANDLED;
+}
+
+static int mtk_syst_clkevt_next_event(unsigned long ticks,
+				      struct clock_event_device *clkevt)
+{
+	struct timer_of *to = to_timer_of(clkevt);
+
+#ifdef SYST_DEBUG
+	t_setevt_in = sched_clock();
+	t_setevt_ticks = ticks;
+	dbg_setevt_cpu = smp_processor_id();
+#endif
+	/* Enable clock to allow timeout tick update later */
+	writel(SYST_CON_EN, SYST_CON_REG(to));
+
+	/*
+	 * Write new timeout ticks. Timer shall start countdown
+	 * after timeout ticks are updated.
+	 */
+	writel(ticks, SYST_VAL_REG(to));
+
+	/* Enable interrupt */
+	writel(SYST_CON_EN | SYST_CON_IRQ_EN, SYST_CON_REG(to));
+
+	return 0;
+}
+
+static int mtk_syst_clkevt_shutdown(struct clock_event_device *clkevt)
+{
+	/* Disable timer */
+	writel(0, SYST_CON_REG(to_timer_of(clkevt)));
+
+	return 0;
+}
+
+static int mtk_syst_clkevt_resume(struct clock_event_device *clkevt)
+{
+	return mtk_syst_clkevt_shutdown(clkevt);
+}
+
+static int mtk_syst_clkevt_oneshot(struct clock_event_device *clkevt)
+{
+	return 0;
+}
+
+static u64 notrace mtk_gpt_read_sched_clock(void)
+{
+	return readl_relaxed(gpt_sched_reg);
+}
+
+static void mtk_gpt_clkevt_time_stop(struct timer_of *to, u8 timer)
+{
+	u32 val;
+
+	/*
+	 * support 32k clock when deepidle, should first use 13m clock config
+	 * timer, then second use 32k clock trigger timer.
+	 */
+	if (to->private_data)
+		writel(GPT_CLK_SRC(GPT_CLK_SRC_SYS13M) | GPT_CLK_DIV1,
+				timer_of_base(to) + GPT_CLK_REG(timer));
+
+	val = readl(timer_of_base(to) + GPT_CTRL_REG(timer));
+	writel(val & ~GPT_CTRL_ENABLE, timer_of_base(to) +
+	       GPT_CTRL_REG(timer));
+}
+
+static void mtk_gpt_clkevt_time_setup(struct timer_of *to,
+				      unsigned long delay, u8 timer)
+{
+	writel(delay, timer_of_base(to) + GPT_CMP_REG(timer));
+}
+
+static void mtk_gpt_clkevt_time_start(struct timer_of *to,
+				      bool periodic, u8 timer)
+{
+	u32 val;
+
+	/* Acknowledge interrupt */
+	writel(GPT_IRQ_ACK(timer), timer_of_base(to) + GPT_IRQ_ACK_REG);
+
+	/*
+	 * support 32k clock when deepidle, should first use 13m clock config
+	 * timer, then second use 32k clock trigger timer.
+	 */
+	if (to->private_data)
+		writel(GPT_CLK_SRC(GPT_CLK_SRC_RTC32K) | GPT_CLK_DIV1,
+				timer_of_base(to) + GPT_CLK_REG(timer));
+
+	val = readl(timer_of_base(to) + GPT_CTRL_REG(timer));
+
+	/* Clear 2 bit timer operation mode field */
+	val &= ~GPT_CTRL_OP(0x3);
+
+	if (periodic)
+		val |= GPT_CTRL_OP(GPT_CTRL_OP_REPEAT);
+	else
+		val |= GPT_CTRL_OP(GPT_CTRL_OP_ONESHOT);
+
+	writel(val | GPT_CTRL_ENABLE | GPT_CTRL_CLEAR,
+	       timer_of_base(to) + GPT_CTRL_REG(timer));
+}
+
+static int mtk_gpt_clkevt_shutdown(struct clock_event_device *clk)
+{
+	mtk_gpt_clkevt_time_stop(to_timer_of(clk), TIMER_CLK_EVT);
+
+	return 0;
+}
+
+static int mtk_gpt_clkevt_set_periodic(struct clock_event_device *clk)
+{
+	struct timer_of *to = to_timer_of(clk);
+
+	mtk_gpt_clkevt_time_stop(to, TIMER_CLK_EVT);
+	mtk_gpt_clkevt_time_setup(to, to->of_clk.period, TIMER_CLK_EVT);
+	mtk_gpt_clkevt_time_start(to, true, TIMER_CLK_EVT);
+
+	return 0;
+}
+
+static int mtk_gpt_clkevt_next_event(unsigned long event,
+				     struct clock_event_device *clk)
+{
+	struct timer_of *to = to_timer_of(clk);
+
+	mtk_gpt_clkevt_time_stop(to, TIMER_CLK_EVT);
+	mtk_gpt_clkevt_time_setup(to, event, TIMER_CLK_EVT);
+	mtk_gpt_clkevt_time_start(to, false, TIMER_CLK_EVT);
+
+	return 0;
+}
+
+static irqreturn_t mtk_gpt_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *clkevt = (struct clock_event_device *)dev_id;
+	struct timer_of *to = to_timer_of(clkevt);
+
+	/* Acknowledge timer0 irq */
+	writel(GPT_IRQ_ACK(TIMER_CLK_EVT), timer_of_base(to) + GPT_IRQ_ACK_REG);
+	clkevt->event_handler(clkevt);
+
+	return IRQ_HANDLED;
+}
+
+static void
+__init mtk_gpt_setup(struct timer_of *to, u8 timer, u8 option, u8 clksrc,
+			bool enable)
+{
+	u32 val;
+
+	writel(GPT_CTRL_CLEAR | GPT_CTRL_DISABLE,
+	       timer_of_base(to) + GPT_CTRL_REG(timer));
+
+	writel(GPT_CLK_SRC(clksrc) | GPT_CLK_DIV1,
+	       timer_of_base(to) + GPT_CLK_REG(timer));
+
+	writel(0x0, timer_of_base(to) + GPT_CMP_REG(timer));
+
+	val = GPT_CTRL_OP(option);
+	if (enable)
+		val |= GPT_CTRL_ENABLE;
+	writel(val, timer_of_base(to) + GPT_CTRL_REG(timer));
+}
+
+static void mtk_gpt_enable_irq(struct timer_of *to, u8 timer)
+{
+	u32 val;
+
+	/* Disable all interrupts */
+	writel(0x0, timer_of_base(to) + GPT_IRQ_EN_REG);
+
+	/* Acknowledge all spurious pending interrupts */
+	writel(0x3f, timer_of_base(to) + GPT_IRQ_ACK_REG);
+
+	val = readl(timer_of_base(to) + GPT_IRQ_EN_REG);
+	writel(val | GPT_IRQ_ENABLE(timer),
+	       timer_of_base(to) + GPT_IRQ_EN_REG);
+}
+
+static struct timer_of to = {
+	.flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK,
+
+	.clkevt = {
+		.name = "mtk-clkevt",
+		.rating = 300,
+		.cpumask = cpu_possible_mask,
+	},
+
+	.of_irq = {
+		.flags = IRQF_TIMER | IRQF_IRQPOLL,
+	},
+};
+
+static int __init mtk_syst_init(struct device_node *node)
+{
+	int ret;
+
+	to.clkevt.features = CLOCK_EVT_FEAT_DYNIRQ | CLOCK_EVT_FEAT_ONESHOT;
+	to.clkevt.set_state_shutdown = mtk_syst_clkevt_shutdown;
+	to.clkevt.set_state_oneshot = mtk_syst_clkevt_oneshot;
+	to.clkevt.tick_resume = mtk_syst_clkevt_resume;
+	to.clkevt.set_next_event = mtk_syst_clkevt_next_event;
+	to.of_irq.handler = mtk_syst_handler;
+
+	ret = timer_of_init(node, &to);
+	if (ret)
+		return ret;
+
+	clockevents_config_and_register(&to.clkevt, timer_of_rate(&to),
+					TIMER_SYNC_TICKS, 0xffffffff);
+
+	return 0;
+}
+
+static int __init mtk_gpt_init(struct device_node *node)
+{
+	int ret;
+	int has_clk32k;
+	struct clk *clk_bus;
+
+	/*
+	 * Sometimes, there is a "bus clk" used as GPT clock gate. It must be
+	 * guaranteed to be opened so that GPT continues to work.
+	 */
+	clk_bus = of_clk_get_by_name(node, "bus");
+	if (!IS_ERR(clk_bus)) {
+		ret = clk_prepare_enable(clk_bus);
+		if (ret)
+			pr_debug("prepare bus clk fail.\n");
+	}
+
+	/*
+	 * CLOCK_EVT_FEAT_DYNIRQ: Core shall set the interrupt affinity
+	 *                        dynamically in broadcast mode.
+	 * CLOCK_EVT_FEAT_ONESHOT: Use one-shot mode for tick broadcast.
+	 */
+	to.clkevt.features = CLOCK_EVT_FEAT_PERIODIC |
+			     CLOCK_EVT_FEAT_ONESHOT |
+			     CLOCK_EVT_FEAT_DYNIRQ;
+	to.clkevt.set_state_shutdown = mtk_gpt_clkevt_shutdown;
+	to.clkevt.set_state_periodic = mtk_gpt_clkevt_set_periodic;
+	to.clkevt.set_state_oneshot = mtk_gpt_clkevt_shutdown;
+	to.clkevt.tick_resume = mtk_gpt_clkevt_shutdown;
+	to.clkevt.set_next_event = mtk_gpt_clkevt_next_event;
+	to.of_irq.handler = mtk_gpt_interrupt;
+
+	/* Use rtc-clk as clock source for clk-evt source if it is exists. */
+	has_clk32k = of_property_match_string(node, "clock-names", "clk32k");
+	if (has_clk32k >= 0)
+		to.of_clk.name = "clk32k";
+
+	ret = timer_of_init(node, &to);
+	if (ret)
+		return ret;
+
+	/* save rtc-clk as .private_data */
+	to.private_data = (has_clk32k < 0) ? NULL : (void *)to.of_clk.clk;
+
+	/* Configure clock source */
+	mtk_gpt_setup(&to, TIMER_CLK_SRC, GPT_CTRL_OP_FREERUN,
+		      (has_clk32k < 0) ? GPT_CLK_SRC_SYS13M :
+		      GPT_CLK_SRC_RTC32K, true);
+	clocksource_mmio_init(timer_of_base(&to) + GPT_CNT_REG(TIMER_CLK_SRC),
+			      node->name, timer_of_rate(&to), 300, 32,
+			      clocksource_mmio_readl_up);
+	gpt_sched_reg = timer_of_base(&to) + GPT_CNT_REG(TIMER_CLK_SRC);
+	sched_clock_register(mtk_gpt_read_sched_clock, 32, timer_of_rate(&to));
+
+	/* Configure clock event */
+	mtk_gpt_setup(&to, TIMER_CLK_EVT, GPT_CTRL_OP_REPEAT,
+		      (has_clk32k < 0) ? GPT_CLK_SRC_SYS13M :
+		      GPT_CLK_SRC_RTC32K, false);
+	clockevents_config_and_register(&to.clkevt, timer_of_rate(&to),
+					TIMER_SYNC_TICKS, 0xffffffff);
+
+	mtk_gpt_enable_irq(&to, TIMER_CLK_EVT);
+
+	return 0;
+}
+TIMER_OF_DECLARE(mtk_mt6577, "mediatek,mt6577-timer", mtk_gpt_init);
+TIMER_OF_DECLARE(mtk_mt6765, "mediatek,mt6765-timer", mtk_syst_init);
+
+#ifdef SYST_DEBUG
+void mtk_timer_clkevt_aee_dump(void)
+{
+	/* interrupt, clkevt handler and set next time */
+	aee_log("[timer-mtk]\n");
+	aee_log("int handler entry:    %llu\n", t_hdl_in);
+	aee_log("set next event entry: %llu\n", t_setevt_in);
+	aee_log("set next event ticks: %llu\n", t_setevt_ticks);
+	aee_log("set next event cpu:   %u\n",   dbg_setevt_cpu);
+	aee_log("CON: 0x%x\n",  readl(SYST_CON_REG(&to)));
+	aee_log("VAL: 0x%x\n",  readl(SYST_VAL_REG(&to)));
+}
+#endif
+

drivers/clocksource/timer-npcm7xx.c

@@ -0,0 +1,215 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2014-2018 Nuvoton Technologies tomer.maimon@nuvoton.com
+ * All rights reserved.
+ *
+ * Copyright 2017 Google, Inc.
+ */
+
+#include <linux/kernel.h>
+#include <linux/sched.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/clockchips.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include "timer-of.h"
+
+/* Timers registers */
+#define NPCM7XX_REG_TCSR0	0x0 /* Timer 0 Control and Status Register */
+#define NPCM7XX_REG_TICR0	0x8 /* Timer 0 Initial Count Register */
+#define NPCM7XX_REG_TCSR1	0x4 /* Timer 1 Control and Status Register */
+#define NPCM7XX_REG_TICR1	0xc /* Timer 1 Initial Count Register */
+#define NPCM7XX_REG_TDR1	0x14 /* Timer 1 Data Register */
+#define NPCM7XX_REG_TISR	0x18 /* Timer Interrupt Status Register */
+
+/* Timers control */
+#define NPCM7XX_Tx_RESETINT		0x1f
+#define NPCM7XX_Tx_PERIOD		BIT(27)
+#define NPCM7XX_Tx_INTEN		BIT(29)
+#define NPCM7XX_Tx_COUNTEN		BIT(30)
+#define NPCM7XX_Tx_ONESHOT		0x0
+#define NPCM7XX_Tx_OPER			GENMASK(3, 27)
+#define NPCM7XX_Tx_MIN_PRESCALE		0x1
+#define NPCM7XX_Tx_TDR_MASK_BITS	24
+#define NPCM7XX_Tx_MAX_CNT		0xFFFFFF
+#define NPCM7XX_T0_CLR_INT		0x1
+#define NPCM7XX_Tx_CLR_CSR		0x0
+
+/* Timers operating mode */
+#define NPCM7XX_START_PERIODIC_Tx (NPCM7XX_Tx_PERIOD | NPCM7XX_Tx_COUNTEN | \
+					NPCM7XX_Tx_INTEN | \
+					NPCM7XX_Tx_MIN_PRESCALE)
+
+#define NPCM7XX_START_ONESHOT_Tx (NPCM7XX_Tx_ONESHOT | NPCM7XX_Tx_COUNTEN | \
+					NPCM7XX_Tx_INTEN | \
+					NPCM7XX_Tx_MIN_PRESCALE)
+
+#define NPCM7XX_START_Tx (NPCM7XX_Tx_COUNTEN | NPCM7XX_Tx_PERIOD | \
+				NPCM7XX_Tx_MIN_PRESCALE)
+
+#define NPCM7XX_DEFAULT_CSR (NPCM7XX_Tx_CLR_CSR | NPCM7XX_Tx_MIN_PRESCALE)
+
+static int npcm7xx_timer_resume(struct clock_event_device *evt)
+{
+	struct timer_of *to = to_timer_of(evt);
+	u32 val;
+
+	val = readl(timer_of_base(to) + NPCM7XX_REG_TCSR0);
+	val |= NPCM7XX_Tx_COUNTEN;
+	writel(val, timer_of_base(to) + NPCM7XX_REG_TCSR0);
+
+	return 0;
+}
+
+static int npcm7xx_timer_shutdown(struct clock_event_device *evt)
+{
+	struct timer_of *to = to_timer_of(evt);
+	u32 val;
+
+	val = readl(timer_of_base(to) + NPCM7XX_REG_TCSR0);
+	val &= ~NPCM7XX_Tx_COUNTEN;
+	writel(val, timer_of_base(to) + NPCM7XX_REG_TCSR0);
+
+	return 0;
+}
+
+static int npcm7xx_timer_oneshot(struct clock_event_device *evt)
+{
+	struct timer_of *to = to_timer_of(evt);
+	u32 val;
+
+	val = readl(timer_of_base(to) + NPCM7XX_REG_TCSR0);
+	val &= ~NPCM7XX_Tx_OPER;
+
+	val = readl(timer_of_base(to) + NPCM7XX_REG_TCSR0);
+	val |= NPCM7XX_START_ONESHOT_Tx;
+	writel(val, timer_of_base(to) + NPCM7XX_REG_TCSR0);
+
+	return 0;
+}
+
+static int npcm7xx_timer_periodic(struct clock_event_device *evt)
+{
+	struct timer_of *to = to_timer_of(evt);
+	u32 val;
+
+	val = readl(timer_of_base(to) + NPCM7XX_REG_TCSR0);
+	val &= ~NPCM7XX_Tx_OPER;
+
+	writel(timer_of_period(to), timer_of_base(to) + NPCM7XX_REG_TICR0);
+	val |= NPCM7XX_START_PERIODIC_Tx;
+
+	writel(val, timer_of_base(to) + NPCM7XX_REG_TCSR0);
+
+	return 0;
+}
+
+static int npcm7xx_clockevent_set_next_event(unsigned long evt,
+		struct clock_event_device *clk)
+{
+	struct timer_of *to = to_timer_of(clk);
+	u32 val;
+
+	writel(evt, timer_of_base(to) + NPCM7XX_REG_TICR0);
+	val = readl(timer_of_base(to) + NPCM7XX_REG_TCSR0);
+	val |= NPCM7XX_START_Tx;
+	writel(val, timer_of_base(to) + NPCM7XX_REG_TCSR0);
+
+	return 0;
+}
+
+static irqreturn_t npcm7xx_timer0_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = (struct clock_event_device *)dev_id;
+	struct timer_of *to = to_timer_of(evt);
+
+	writel(NPCM7XX_T0_CLR_INT, timer_of_base(to) + NPCM7XX_REG_TISR);
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static struct timer_of npcm7xx_to = {
+	.flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK,
+
+	.clkevt = {
+		.name		    = "npcm7xx-timer0",
+		.features	    = CLOCK_EVT_FEAT_PERIODIC |
+				      CLOCK_EVT_FEAT_ONESHOT,
+		.set_next_event	    = npcm7xx_clockevent_set_next_event,
+		.set_state_shutdown = npcm7xx_timer_shutdown,
+		.set_state_periodic = npcm7xx_timer_periodic,
+		.set_state_oneshot  = npcm7xx_timer_oneshot,
+		.tick_resume	    = npcm7xx_timer_resume,
+		.rating		    = 300,
+	},
+
+	.of_irq = {
+		.handler = npcm7xx_timer0_interrupt,
+		.flags = IRQF_TIMER | IRQF_IRQPOLL,
+	},
+};
+
+static void __init npcm7xx_clockevents_init(void)
+{
+	writel(NPCM7XX_DEFAULT_CSR,
+		timer_of_base(&npcm7xx_to) + NPCM7XX_REG_TCSR0);
+
+	writel(NPCM7XX_Tx_RESETINT,
+		timer_of_base(&npcm7xx_to) + NPCM7XX_REG_TISR);
+
+	npcm7xx_to.clkevt.cpumask = cpumask_of(0);
+	clockevents_config_and_register(&npcm7xx_to.clkevt,
+					timer_of_rate(&npcm7xx_to),
+					0x1, NPCM7XX_Tx_MAX_CNT);
+}
+
+static void __init npcm7xx_clocksource_init(void)
+{
+	u32 val;
+
+	writel(NPCM7XX_DEFAULT_CSR,
+		timer_of_base(&npcm7xx_to) + NPCM7XX_REG_TCSR1);
+	writel(NPCM7XX_Tx_MAX_CNT,
+		timer_of_base(&npcm7xx_to) + NPCM7XX_REG_TICR1);
+
+	val = readl(timer_of_base(&npcm7xx_to) + NPCM7XX_REG_TCSR1);
+	val |= NPCM7XX_START_Tx;
+	writel(val, timer_of_base(&npcm7xx_to) + NPCM7XX_REG_TCSR1);
+
+	clocksource_mmio_init(timer_of_base(&npcm7xx_to) +
+				NPCM7XX_REG_TDR1,
+				"npcm7xx-timer1", timer_of_rate(&npcm7xx_to),
+				200, (unsigned int)NPCM7XX_Tx_TDR_MASK_BITS,
+				clocksource_mmio_readl_down);
+}
+
+static int __init npcm7xx_timer_init(struct device_node *np)
+{
+	int ret;
+
+	ret = timer_of_init(np, &npcm7xx_to);
+	if (ret)
+		return ret;
+
+	/* Clock input is divided by PRESCALE + 1 before it is fed */
+	/* to the counter */
+	npcm7xx_to.of_clk.rate = npcm7xx_to.of_clk.rate /
+		(NPCM7XX_Tx_MIN_PRESCALE + 1);
+
+	npcm7xx_clocksource_init();
+	npcm7xx_clockevents_init();
+
+	pr_info("Enabling NPCM7xx clocksource timer base: %px, IRQ: %d ",
+		timer_of_base(&npcm7xx_to), timer_of_irq(&npcm7xx_to));
+
+	return 0;
+}
+
+TIMER_OF_DECLARE(npcm7xx, "nuvoton,npcm750-timer", npcm7xx_timer_init);
+

drivers/clocksource/timer-nps.c

@@ -0,0 +1,284 @@
+/*
+ * Copyright (c) 2016, Mellanox Technologies. All rights reserved.
+ *
+ * This software is available to you under a choice of one of two
+ * licenses.  You may choose to be licensed under the terms of the GNU
+ * General Public License (GPL) Version 2, available from the file
+ * COPYING in the main directory of this source tree, or the
+ * OpenIB.org BSD license below:
+ *
+ *     Redistribution and use in source and binary forms, with or
+ *     without modification, are permitted provided that the following
+ *     conditions are met:
+ *
+ *      - Redistributions of source code must retain the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer.
+ *
+ *      - Redistributions in binary form must reproduce the above
+ *        copyright notice, this list of conditions and the following
+ *        disclaimer in the documentation and/or other materials
+ *        provided with the distribution.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/clk.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/cpu.h>
+#include <soc/nps/common.h>
+
+#define NPS_MSU_TICK_LOW	0xC8
+#define NPS_CLUSTER_OFFSET	8
+#define NPS_CLUSTER_NUM		16
+
+/* This array is per cluster of CPUs (Each NPS400 cluster got 256 CPUs) */
+static void *nps_msu_reg_low_addr[NPS_CLUSTER_NUM] __read_mostly;
+
+static int __init nps_get_timer_clk(struct device_node *node,
+			     unsigned long *timer_freq,
+			     struct clk **clk)
+{
+	int ret;
+
+	*clk = of_clk_get(node, 0);
+	ret = PTR_ERR_OR_ZERO(*clk);
+	if (ret) {
+		pr_err("timer missing clk\n");
+		return ret;
+	}
+
+	ret = clk_prepare_enable(*clk);
+	if (ret) {
+		pr_err("Couldn't enable parent clk\n");
+		clk_put(*clk);
+		return ret;
+	}
+
+	*timer_freq = clk_get_rate(*clk);
+	if (!(*timer_freq)) {
+		pr_err("Couldn't get clk rate\n");
+		clk_disable_unprepare(*clk);
+		clk_put(*clk);
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static u64 nps_clksrc_read(struct clocksource *clksrc)
+{
+	int cluster = raw_smp_processor_id() >> NPS_CLUSTER_OFFSET;
+
+	return (u64)ioread32be(nps_msu_reg_low_addr[cluster]);
+}
+
+static int __init nps_setup_clocksource(struct device_node *node)
+{
+	int ret, cluster;
+	struct clk *clk;
+	unsigned long nps_timer1_freq;
+
+
+	for (cluster = 0; cluster < NPS_CLUSTER_NUM; cluster++)
+		nps_msu_reg_low_addr[cluster] =
+			nps_host_reg((cluster << NPS_CLUSTER_OFFSET),
+				     NPS_MSU_BLKID, NPS_MSU_TICK_LOW);
+
+	ret = nps_get_timer_clk(node, &nps_timer1_freq, &clk);
+	if (ret)
+		return ret;
+
+	ret = clocksource_mmio_init(nps_msu_reg_low_addr, "nps-tick",
+				    nps_timer1_freq, 300, 32, nps_clksrc_read);
+	if (ret) {
+		pr_err("Couldn't register clock source.\n");
+		clk_disable_unprepare(clk);
+	}
+
+	return ret;
+}
+
+TIMER_OF_DECLARE(ezchip_nps400_clksrc, "ezchip,nps400-timer",
+		       nps_setup_clocksource);
+TIMER_OF_DECLARE(ezchip_nps400_clk_src, "ezchip,nps400-timer1",
+		       nps_setup_clocksource);
+
+#ifdef CONFIG_EZNPS_MTM_EXT
+#include <soc/nps/mtm.h>
+
+/* Timer related Aux registers */
+#define NPS_REG_TIMER0_TSI	0xFFFFF850
+#define NPS_REG_TIMER0_LIMIT	0x23
+#define NPS_REG_TIMER0_CTRL	0x22
+#define NPS_REG_TIMER0_CNT	0x21
+
+/*
+ * Interrupt Enabled (IE) - re-arm the timer
+ * Not Halted (NH) - is cleared when working with JTAG (for debug)
+ */
+#define TIMER0_CTRL_IE		BIT(0)
+#define TIMER0_CTRL_NH		BIT(1)
+
+static unsigned long nps_timer0_freq;
+static unsigned long nps_timer0_irq;
+
+static void nps_clkevent_rm_thread(void)
+{
+	int thread;
+	unsigned int cflags, enabled_threads;
+
+	hw_schd_save(&cflags);
+
+	enabled_threads = read_aux_reg(NPS_REG_TIMER0_TSI);
+
+	/* remove thread from TSI1 */
+	thread = read_aux_reg(CTOP_AUX_THREAD_ID);
+	enabled_threads &= ~(1 << thread);
+	write_aux_reg(NPS_REG_TIMER0_TSI, enabled_threads);
+
+	/* Acknowledge and if needed re-arm the timer */
+	if (!enabled_threads)
+		write_aux_reg(NPS_REG_TIMER0_CTRL, TIMER0_CTRL_NH);
+	else
+		write_aux_reg(NPS_REG_TIMER0_CTRL,
+			      TIMER0_CTRL_IE | TIMER0_CTRL_NH);
+
+	hw_schd_restore(cflags);
+}
+
+static void nps_clkevent_add_thread(unsigned long delta)
+{
+	int thread;
+	unsigned int cflags, enabled_threads;
+
+	hw_schd_save(&cflags);
+
+	/* add thread to TSI1 */
+	thread = read_aux_reg(CTOP_AUX_THREAD_ID);
+	enabled_threads = read_aux_reg(NPS_REG_TIMER0_TSI);
+	enabled_threads |= (1 << thread);
+	write_aux_reg(NPS_REG_TIMER0_TSI, enabled_threads);
+
+	/* set next timer event */
+	write_aux_reg(NPS_REG_TIMER0_LIMIT, delta);
+	write_aux_reg(NPS_REG_TIMER0_CNT, 0);
+	write_aux_reg(NPS_REG_TIMER0_CTRL,
+		      TIMER0_CTRL_IE | TIMER0_CTRL_NH);
+
+	hw_schd_restore(cflags);
+}
+
+/*
+ * Whenever anyone tries to change modes, we just mask interrupts
+ * and wait for the next event to get set.
+ */
+static int nps_clkevent_set_state(struct clock_event_device *dev)
+{
+	nps_clkevent_rm_thread();
+	disable_percpu_irq(nps_timer0_irq);
+
+	return 0;
+}
+
+static int nps_clkevent_set_next_event(unsigned long delta,
+				       struct clock_event_device *dev)
+{
+	nps_clkevent_add_thread(delta);
+	enable_percpu_irq(nps_timer0_irq, IRQ_TYPE_NONE);
+
+	return 0;
+}
+
+static DEFINE_PER_CPU(struct clock_event_device, nps_clockevent_device) = {
+	.name				=	"NPS Timer0",
+	.features			=	CLOCK_EVT_FEAT_ONESHOT,
+	.rating				=	300,
+	.set_next_event			=	nps_clkevent_set_next_event,
+	.set_state_oneshot		=	nps_clkevent_set_state,
+	.set_state_oneshot_stopped	=	nps_clkevent_set_state,
+	.set_state_shutdown		=	nps_clkevent_set_state,
+	.tick_resume			=	nps_clkevent_set_state,
+};
+
+static irqreturn_t timer_irq_handler(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	nps_clkevent_rm_thread();
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static int nps_timer_starting_cpu(unsigned int cpu)
+{
+	struct clock_event_device *evt = this_cpu_ptr(&nps_clockevent_device);
+
+	evt->cpumask = cpumask_of(smp_processor_id());
+
+	clockevents_config_and_register(evt, nps_timer0_freq, 0, ULONG_MAX);
+	enable_percpu_irq(nps_timer0_irq, IRQ_TYPE_NONE);
+
+	return 0;
+}
+
+static int nps_timer_dying_cpu(unsigned int cpu)
+{
+	disable_percpu_irq(nps_timer0_irq);
+	return 0;
+}
+
+static int __init nps_setup_clockevent(struct device_node *node)
+{
+	struct clk *clk;
+	int ret;
+
+	nps_timer0_irq = irq_of_parse_and_map(node, 0);
+	if (nps_timer0_irq <= 0) {
+		pr_err("clockevent: missing irq\n");
+		return -EINVAL;
+	}
+
+	ret = nps_get_timer_clk(node, &nps_timer0_freq, &clk);
+	if (ret)
+		return ret;
+
+	/* Needs apriori irq_set_percpu_devid() done in intc map function */
+	ret = request_percpu_irq(nps_timer0_irq, timer_irq_handler,
+				 "Timer0 (per-cpu-tick)",
+				 &nps_clockevent_device);
+	if (ret) {
+		pr_err("Couldn't request irq\n");
+		clk_disable_unprepare(clk);
+		return ret;
+	}
+
+	ret = cpuhp_setup_state(CPUHP_AP_ARC_TIMER_STARTING,
+				"clockevents/nps:starting",
+				nps_timer_starting_cpu,
+				nps_timer_dying_cpu);
+	if (ret) {
+		pr_err("Failed to setup hotplug state\n");
+		clk_disable_unprepare(clk);
+		free_percpu_irq(nps_timer0_irq, &nps_clockevent_device);
+		return ret;
+	}
+
+	return 0;
+}
+
+TIMER_OF_DECLARE(ezchip_nps400_clk_evt, "ezchip,nps400-timer0",
+		       nps_setup_clockevent);
+#endif /* CONFIG_EZNPS_MTM_EXT */

drivers/clocksource/timer-of.c

@@ -0,0 +1,237 @@
+/*
+ * Copyright (c) 2017, Linaro Ltd.  All rights reserved.
+ *
+ * Author: Daniel Lezcano <daniel.lezcano@linaro.org>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include <linux/clk.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/slab.h>
+
+#include "timer-of.h"
+
+/**
+ * timer_of_irq_exit - Release the interrupt
+ * @of_irq: an of_timer_irq structure pointer
+ *
+ * Free the irq resource
+ */
+static __init void timer_of_irq_exit(struct of_timer_irq *of_irq)
+{
+	struct timer_of *to = container_of(of_irq, struct timer_of, of_irq);
+
+	struct clock_event_device *clkevt = &to->clkevt;
+
+	of_irq->percpu ? free_percpu_irq(of_irq->irq, clkevt) :
+		free_irq(of_irq->irq, clkevt);
+}
+
+/**
+ * timer_of_irq_init - Request the interrupt
+ * @np: a device tree node pointer
+ * @of_irq: an of_timer_irq structure pointer
+ *
+ * Get the interrupt number from the DT from its definition and
+ * request it. The interrupt is gotten by falling back the following way:
+ *
+ * - Get interrupt number by name
+ * - Get interrupt number by index
+ *
+ * When the interrupt is per CPU, 'request_percpu_irq()' is called,
+ * otherwise 'request_irq()' is used.
+ *
+ * Returns 0 on success, < 0 otherwise
+ */
+static __init int timer_of_irq_init(struct device_node *np,
+				    struct of_timer_irq *of_irq)
+{
+	int ret;
+	struct timer_of *to = container_of(of_irq, struct timer_of, of_irq);
+	struct clock_event_device *clkevt = &to->clkevt;
+
+	if (of_irq->name) {
+		of_irq->irq = ret = of_irq_get_byname(np, of_irq->name);
+		if (ret < 0) {
+			pr_err("Failed to get interrupt %s for %s\n",
+			       of_irq->name, np->full_name);
+			return ret;
+		}
+	} else	{
+		of_irq->irq = irq_of_parse_and_map(np, of_irq->index);
+	}
+	if (!of_irq->irq) {
+		pr_err("Failed to map interrupt for %pOF\n", np);
+		return -EINVAL;
+	}
+
+	ret = of_irq->percpu ?
+		request_percpu_irq(of_irq->irq, of_irq->handler,
+				   np->full_name, clkevt) :
+		request_irq(of_irq->irq, of_irq->handler,
+			    of_irq->flags ? of_irq->flags : IRQF_TIMER,
+			    np->full_name, clkevt);
+	if (ret) {
+		pr_err("Failed to request irq %d for %pOF\n", of_irq->irq, np);
+		return ret;
+	}
+
+	clkevt->irq = of_irq->irq;
+
+	return 0;
+}
+
+/**
+ * timer_of_clk_exit - Release the clock resources
+ * @of_clk: a of_timer_clk structure pointer
+ *
+ * Disables and releases the refcount on the clk
+ */
+static __init void timer_of_clk_exit(struct of_timer_clk *of_clk)
+{
+	of_clk->rate = 0;
+	clk_disable_unprepare(of_clk->clk);
+	clk_put(of_clk->clk);
+}
+
+/**
+ * timer_of_clk_init - Initialize the clock resources
+ * @np: a device tree node pointer
+ * @of_clk: a of_timer_clk structure pointer
+ *
+ * Get the clock by name or by index, enable it and get the rate
+ *
+ * Returns 0 on success, < 0 otherwise
+ */
+static __init int timer_of_clk_init(struct device_node *np,
+				    struct of_timer_clk *of_clk)
+{
+	int ret;
+
+	of_clk->clk = of_clk->name ? of_clk_get_by_name(np, of_clk->name) :
+		of_clk_get(np, of_clk->index);
+	if (IS_ERR(of_clk->clk)) {
+		pr_err("Failed to get clock for %pOF\n", np);
+		return PTR_ERR(of_clk->clk);
+	}
+
+	ret = clk_prepare_enable(of_clk->clk);
+	if (ret) {
+		pr_err("Failed for enable clock for %pOF\n", np);
+		goto out_clk_put;
+	}
+
+	of_clk->rate = clk_get_rate(of_clk->clk);
+	if (!of_clk->rate) {
+		ret = -EINVAL;
+		pr_err("Failed to get clock rate for %pOF\n", np);
+		goto out_clk_disable;
+	}
+
+	of_clk->period = DIV_ROUND_UP(of_clk->rate, HZ);
+out:
+	return ret;
+
+out_clk_disable:
+	clk_disable_unprepare(of_clk->clk);
+out_clk_put:
+	clk_put(of_clk->clk);
+
+	goto out;
+}
+
+static __init void timer_of_base_exit(struct of_timer_base *of_base)
+{
+	iounmap(of_base->base);
+}
+
+static __init int timer_of_base_init(struct device_node *np,
+				     struct of_timer_base *of_base)
+{
+	of_base->base = of_base->name ?
+		of_io_request_and_map(np, of_base->index, of_base->name) :
+		of_iomap(np, of_base->index);
+	if (IS_ERR(of_base->base)) {
+		pr_err("Failed to iomap (%s)\n", of_base->name);
+		return PTR_ERR(of_base->base);
+	}
+
+	return 0;
+}
+
+int __init timer_of_init(struct device_node *np, struct timer_of *to)
+{
+	int ret = -EINVAL;
+	int flags = 0;
+
+	if (to->flags & TIMER_OF_BASE) {
+		ret = timer_of_base_init(np, &to->of_base);
+		if (ret)
+			goto out_fail;
+		flags |= TIMER_OF_BASE;
+	}
+
+	if (to->flags & TIMER_OF_CLOCK) {
+		ret = timer_of_clk_init(np, &to->of_clk);
+		if (ret)
+			goto out_fail;
+		flags |= TIMER_OF_CLOCK;
+	}
+
+	if (to->flags & TIMER_OF_IRQ) {
+		ret = timer_of_irq_init(np, &to->of_irq);
+		if (ret)
+			goto out_fail;
+		flags |= TIMER_OF_IRQ;
+	}
+
+	if (!to->clkevt.name)
+		to->clkevt.name = np->full_name;
+
+	to->np = np;
+
+	return ret;
+
+out_fail:
+	if (flags & TIMER_OF_IRQ)
+		timer_of_irq_exit(&to->of_irq);
+
+	if (flags & TIMER_OF_CLOCK)
+		timer_of_clk_exit(&to->of_clk);
+
+	if (flags & TIMER_OF_BASE)
+		timer_of_base_exit(&to->of_base);
+	return ret;
+}
+
+/**
+ * timer_of_cleanup - release timer_of ressources
+ * @to: timer_of structure
+ *
+ * Release the ressources that has been used in timer_of_init().
+ * This function should be called in init error cases
+ */
+void __init timer_of_cleanup(struct timer_of *to)
+{
+	if (to->flags & TIMER_OF_IRQ)
+		timer_of_irq_exit(&to->of_irq);
+
+	if (to->flags & TIMER_OF_CLOCK)
+		timer_of_clk_exit(&to->of_clk);
+
+	if (to->flags & TIMER_OF_BASE)
+		timer_of_base_exit(&to->of_base);
+}

drivers/clocksource/timer-of.h

@@ -0,0 +1,74 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __TIMER_OF_H__
+#define __TIMER_OF_H__
+
+#include <linux/clockchips.h>
+
+#define TIMER_OF_BASE	0x1
+#define TIMER_OF_CLOCK	0x2
+#define TIMER_OF_IRQ	0x4
+
+struct of_timer_irq {
+	int irq;
+	int index;
+	int percpu;
+	const char *name;
+	unsigned long flags;
+	irq_handler_t handler;
+};
+
+struct of_timer_base {
+	void __iomem *base;
+	const char *name;
+	int index;
+};
+
+struct of_timer_clk {
+	struct clk *clk;
+	const char *name;
+	int index;
+	unsigned long rate;
+	unsigned long period;
+};
+
+struct timer_of {
+	unsigned int flags;
+	struct device_node *np;
+	struct clock_event_device clkevt;
+	struct of_timer_base of_base;
+	struct of_timer_irq  of_irq;
+	struct of_timer_clk  of_clk;
+	void *private_data;
+};
+
+static inline struct timer_of *to_timer_of(struct clock_event_device *clkevt)
+{
+	return container_of(clkevt, struct timer_of, clkevt);
+}
+
+static inline void __iomem *timer_of_base(struct timer_of *to)
+{
+	return to->of_base.base;
+}
+
+static inline int timer_of_irq(struct timer_of *to)
+{
+	return to->of_irq.irq;
+}
+
+static inline unsigned long timer_of_rate(struct timer_of *to)
+{
+	return to->of_clk.rate;
+}
+
+static inline unsigned long timer_of_period(struct timer_of *to)
+{
+	return to->of_clk.period;
+}
+
+extern int __init timer_of_init(struct device_node *np,
+				struct timer_of *to);
+
+extern void __init timer_of_cleanup(struct timer_of *to);
+
+#endif

drivers/clocksource/timer-oxnas-rps.c

@@ -0,0 +1,299 @@
+/*
+ * drivers/clocksource/timer-oxnas-rps.c
+ *
+ * Copyright (C) 2009 Oxford Semiconductor Ltd
+ * Copyright (C) 2013 Ma Haijun <mahaijuns@gmail.com>
+ * Copyright (C) 2016 Neil Armstrong <narmstrong@baylibre.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/clockchips.h>
+#include <linux/sched_clock.h>
+
+/* TIMER1 used as tick
+ * TIMER2 used as clocksource
+ */
+
+/* Registers definitions */
+
+#define TIMER_LOAD_REG		0x0
+#define TIMER_CURR_REG		0x4
+#define TIMER_CTRL_REG		0x8
+#define TIMER_CLRINT_REG	0xC
+
+#define TIMER_BITS		24
+
+#define TIMER_MAX_VAL		(BIT(TIMER_BITS) - 1)
+
+#define TIMER_PERIODIC		BIT(6)
+#define TIMER_ENABLE		BIT(7)
+
+#define TIMER_DIV1		(0)
+#define TIMER_DIV16		(1 << 2)
+#define TIMER_DIV256		(2 << 2)
+
+#define TIMER1_REG_OFFSET	0
+#define TIMER2_REG_OFFSET	0x20
+
+/* Clockevent & Clocksource data */
+
+struct oxnas_rps_timer {
+	struct clock_event_device clkevent;
+	void __iomem *clksrc_base;
+	void __iomem *clkevt_base;
+	unsigned long timer_period;
+	unsigned int timer_prescaler;
+	struct clk *clk;
+	int irq;
+};
+
+static irqreturn_t oxnas_rps_timer_irq(int irq, void *dev_id)
+{
+	struct oxnas_rps_timer *rps = dev_id;
+
+	writel_relaxed(0, rps->clkevt_base + TIMER_CLRINT_REG);
+
+	rps->clkevent.event_handler(&rps->clkevent);
+
+	return IRQ_HANDLED;
+}
+
+static void oxnas_rps_timer_config(struct oxnas_rps_timer *rps,
+				   unsigned long period,
+				   unsigned int periodic)
+{
+	uint32_t cfg = rps->timer_prescaler;
+
+	if (period)
+		cfg |= TIMER_ENABLE;
+
+	if (periodic)
+		cfg |= TIMER_PERIODIC;
+
+	writel_relaxed(period, rps->clkevt_base + TIMER_LOAD_REG);
+	writel_relaxed(cfg, rps->clkevt_base + TIMER_CTRL_REG);
+}
+
+static int oxnas_rps_timer_shutdown(struct clock_event_device *evt)
+{
+	struct oxnas_rps_timer *rps =
+		container_of(evt, struct oxnas_rps_timer, clkevent);
+
+	oxnas_rps_timer_config(rps, 0, 0);
+
+	return 0;
+}
+
+static int oxnas_rps_timer_set_periodic(struct clock_event_device *evt)
+{
+	struct oxnas_rps_timer *rps =
+		container_of(evt, struct oxnas_rps_timer, clkevent);
+
+	oxnas_rps_timer_config(rps, rps->timer_period, 1);
+
+	return 0;
+}
+
+static int oxnas_rps_timer_set_oneshot(struct clock_event_device *evt)
+{
+	struct oxnas_rps_timer *rps =
+		container_of(evt, struct oxnas_rps_timer, clkevent);
+
+	oxnas_rps_timer_config(rps, rps->timer_period, 0);
+
+	return 0;
+}
+
+static int oxnas_rps_timer_next_event(unsigned long delta,
+				struct clock_event_device *evt)
+{
+	struct oxnas_rps_timer *rps =
+		container_of(evt, struct oxnas_rps_timer, clkevent);
+
+	oxnas_rps_timer_config(rps, delta, 0);
+
+	return 0;
+}
+
+static int __init oxnas_rps_clockevent_init(struct oxnas_rps_timer *rps)
+{
+	ulong clk_rate = clk_get_rate(rps->clk);
+	ulong timer_rate;
+
+	/* Start with prescaler 1 */
+	rps->timer_prescaler = TIMER_DIV1;
+	rps->timer_period = DIV_ROUND_UP(clk_rate, HZ);
+	timer_rate = clk_rate;
+
+	if (rps->timer_period > TIMER_MAX_VAL) {
+		rps->timer_prescaler = TIMER_DIV16;
+		timer_rate = clk_rate / 16;
+		rps->timer_period = DIV_ROUND_UP(timer_rate, HZ);
+	}
+	if (rps->timer_period > TIMER_MAX_VAL) {
+		rps->timer_prescaler = TIMER_DIV256;
+		timer_rate = clk_rate / 256;
+		rps->timer_period = DIV_ROUND_UP(timer_rate, HZ);
+	}
+
+	rps->clkevent.name = "oxnas-rps";
+	rps->clkevent.features = CLOCK_EVT_FEAT_PERIODIC |
+				 CLOCK_EVT_FEAT_ONESHOT |
+				 CLOCK_EVT_FEAT_DYNIRQ;
+	rps->clkevent.tick_resume = oxnas_rps_timer_shutdown;
+	rps->clkevent.set_state_shutdown = oxnas_rps_timer_shutdown;
+	rps->clkevent.set_state_periodic = oxnas_rps_timer_set_periodic;
+	rps->clkevent.set_state_oneshot = oxnas_rps_timer_set_oneshot;
+	rps->clkevent.set_next_event = oxnas_rps_timer_next_event;
+	rps->clkevent.rating = 200;
+	rps->clkevent.cpumask = cpu_possible_mask;
+	rps->clkevent.irq = rps->irq;
+	clockevents_config_and_register(&rps->clkevent,
+					timer_rate,
+					1,
+					TIMER_MAX_VAL);
+
+	pr_info("Registered clock event rate %luHz prescaler %x period %lu\n",
+			clk_rate,
+			rps->timer_prescaler,
+			rps->timer_period);
+
+	return 0;
+}
+
+/* Clocksource */
+
+static void __iomem *timer_sched_base;
+
+static u64 notrace oxnas_rps_read_sched_clock(void)
+{
+	return ~readl_relaxed(timer_sched_base);
+}
+
+static int __init oxnas_rps_clocksource_init(struct oxnas_rps_timer *rps)
+{
+	ulong clk_rate = clk_get_rate(rps->clk);
+	int ret;
+
+	/* use prescale 16 */
+	clk_rate = clk_rate / 16;
+
+	writel_relaxed(TIMER_MAX_VAL, rps->clksrc_base + TIMER_LOAD_REG);
+	writel_relaxed(TIMER_PERIODIC | TIMER_ENABLE | TIMER_DIV16,
+			rps->clksrc_base + TIMER_CTRL_REG);
+
+	timer_sched_base = rps->clksrc_base + TIMER_CURR_REG;
+	sched_clock_register(oxnas_rps_read_sched_clock,
+			     TIMER_BITS, clk_rate);
+	ret = clocksource_mmio_init(timer_sched_base,
+				    "oxnas_rps_clocksource_timer",
+				    clk_rate, 250, TIMER_BITS,
+				    clocksource_mmio_readl_down);
+	if (WARN_ON(ret)) {
+		pr_err("can't register clocksource\n");
+		return ret;
+	}
+
+	pr_info("Registered clocksource rate %luHz\n", clk_rate);
+
+	return 0;
+}
+
+static int __init oxnas_rps_timer_init(struct device_node *np)
+{
+	struct oxnas_rps_timer *rps;
+	void __iomem *base;
+	int ret;
+
+	rps = kzalloc(sizeof(*rps), GFP_KERNEL);
+	if (!rps)
+		return -ENOMEM;
+
+	rps->clk = of_clk_get(np, 0);
+	if (IS_ERR(rps->clk)) {
+		ret = PTR_ERR(rps->clk);
+		goto err_alloc;
+	}
+
+	ret = clk_prepare_enable(rps->clk);
+	if (ret)
+		goto err_clk;
+
+	base = of_iomap(np, 0);
+	if (!base) {
+		ret = -ENXIO;
+		goto err_clk_prepare;
+	}
+
+	rps->irq = irq_of_parse_and_map(np, 0);
+	if (rps->irq < 0) {
+		ret = -EINVAL;
+		goto err_iomap;
+	}
+
+	rps->clkevt_base = base + TIMER1_REG_OFFSET;
+	rps->clksrc_base = base + TIMER2_REG_OFFSET;
+
+	/* Disable timers */
+	writel_relaxed(0, rps->clkevt_base + TIMER_CTRL_REG);
+	writel_relaxed(0, rps->clksrc_base + TIMER_CTRL_REG);
+	writel_relaxed(0, rps->clkevt_base + TIMER_LOAD_REG);
+	writel_relaxed(0, rps->clksrc_base + TIMER_LOAD_REG);
+	writel_relaxed(0, rps->clkevt_base + TIMER_CLRINT_REG);
+	writel_relaxed(0, rps->clksrc_base + TIMER_CLRINT_REG);
+
+	ret = request_irq(rps->irq, oxnas_rps_timer_irq,
+			  IRQF_TIMER | IRQF_IRQPOLL,
+			  "rps-timer", rps);
+	if (ret)
+		goto err_iomap;
+
+	ret = oxnas_rps_clocksource_init(rps);
+	if (ret)
+		goto err_irqreq;
+
+	ret = oxnas_rps_clockevent_init(rps);
+	if (ret)
+		goto err_irqreq;
+
+	return 0;
+
+err_irqreq:
+	free_irq(rps->irq, rps);
+err_iomap:
+	iounmap(base);
+err_clk_prepare:
+	clk_disable_unprepare(rps->clk);
+err_clk:
+	clk_put(rps->clk);
+err_alloc:
+	kfree(rps);
+
+	return ret;
+}
+
+TIMER_OF_DECLARE(ox810se_rps,
+		       "oxsemi,ox810se-rps-timer", oxnas_rps_timer_init);
+TIMER_OF_DECLARE(ox820_rps,
+		       "oxsemi,ox820-rps-timer", oxnas_rps_timer_init);

drivers/clocksource/timer-prima2.c

@@ -0,0 +1,249 @@
+/*
+ * System timer for CSR SiRFprimaII
+ *
+ * Copyright (c) 2011 Cambridge Silicon Radio Limited, a CSR plc group company.
+ *
+ * Licensed under GPLv2 or later.
+ */
+
+#include <linux/kernel.h>
+#include <linux/interrupt.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/bitops.h>
+#include <linux/irq.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
+#include <linux/sched_clock.h>
+
+#define PRIMA2_CLOCK_FREQ 1000000
+
+#define SIRFSOC_TIMER_COUNTER_LO	0x0000
+#define SIRFSOC_TIMER_COUNTER_HI	0x0004
+#define SIRFSOC_TIMER_MATCH_0		0x0008
+#define SIRFSOC_TIMER_MATCH_1		0x000C
+#define SIRFSOC_TIMER_MATCH_2		0x0010
+#define SIRFSOC_TIMER_MATCH_3		0x0014
+#define SIRFSOC_TIMER_MATCH_4		0x0018
+#define SIRFSOC_TIMER_MATCH_5		0x001C
+#define SIRFSOC_TIMER_STATUS		0x0020
+#define SIRFSOC_TIMER_INT_EN		0x0024
+#define SIRFSOC_TIMER_WATCHDOG_EN	0x0028
+#define SIRFSOC_TIMER_DIV		0x002C
+#define SIRFSOC_TIMER_LATCH		0x0030
+#define SIRFSOC_TIMER_LATCHED_LO	0x0034
+#define SIRFSOC_TIMER_LATCHED_HI	0x0038
+
+#define SIRFSOC_TIMER_WDT_INDEX		5
+
+#define SIRFSOC_TIMER_LATCH_BIT	 BIT(0)
+
+#define SIRFSOC_TIMER_REG_CNT 11
+
+static const u32 sirfsoc_timer_reg_list[SIRFSOC_TIMER_REG_CNT] = {
+	SIRFSOC_TIMER_MATCH_0, SIRFSOC_TIMER_MATCH_1, SIRFSOC_TIMER_MATCH_2,
+	SIRFSOC_TIMER_MATCH_3, SIRFSOC_TIMER_MATCH_4, SIRFSOC_TIMER_MATCH_5,
+	SIRFSOC_TIMER_INT_EN, SIRFSOC_TIMER_WATCHDOG_EN, SIRFSOC_TIMER_DIV,
+	SIRFSOC_TIMER_LATCHED_LO, SIRFSOC_TIMER_LATCHED_HI,
+};
+
+static u32 sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT];
+
+static void __iomem *sirfsoc_timer_base;
+
+/* timer0 interrupt handler */
+static irqreturn_t sirfsoc_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *ce = dev_id;
+
+	WARN_ON(!(readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_STATUS) &
+		BIT(0)));
+
+	/* clear timer0 interrupt */
+	writel_relaxed(BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_STATUS);
+
+	ce->event_handler(ce);
+
+	return IRQ_HANDLED;
+}
+
+/* read 64-bit timer counter */
+static u64 notrace sirfsoc_timer_read(struct clocksource *cs)
+{
+	u64 cycles;
+
+	/* latch the 64-bit timer counter */
+	writel_relaxed(SIRFSOC_TIMER_LATCH_BIT,
+		sirfsoc_timer_base + SIRFSOC_TIMER_LATCH);
+	cycles = readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_LATCHED_HI);
+	cycles = (cycles << 32) |
+		readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_LATCHED_LO);
+
+	return cycles;
+}
+
+static int sirfsoc_timer_set_next_event(unsigned long delta,
+	struct clock_event_device *ce)
+{
+	unsigned long now, next;
+
+	writel_relaxed(SIRFSOC_TIMER_LATCH_BIT,
+		sirfsoc_timer_base + SIRFSOC_TIMER_LATCH);
+	now = readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_LATCHED_LO);
+	next = now + delta;
+	writel_relaxed(next, sirfsoc_timer_base + SIRFSOC_TIMER_MATCH_0);
+	writel_relaxed(SIRFSOC_TIMER_LATCH_BIT,
+		sirfsoc_timer_base + SIRFSOC_TIMER_LATCH);
+	now = readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_LATCHED_LO);
+
+	return next - now > delta ? -ETIME : 0;
+}
+
+static int sirfsoc_timer_shutdown(struct clock_event_device *evt)
+{
+	u32 val = readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_INT_EN);
+
+	writel_relaxed(val & ~BIT(0),
+		       sirfsoc_timer_base + SIRFSOC_TIMER_INT_EN);
+	return 0;
+}
+
+static int sirfsoc_timer_set_oneshot(struct clock_event_device *evt)
+{
+	u32 val = readl_relaxed(sirfsoc_timer_base + SIRFSOC_TIMER_INT_EN);
+
+	writel_relaxed(val | BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_INT_EN);
+	return 0;
+}
+
+static void sirfsoc_clocksource_suspend(struct clocksource *cs)
+{
+	int i;
+
+	writel_relaxed(SIRFSOC_TIMER_LATCH_BIT,
+		sirfsoc_timer_base + SIRFSOC_TIMER_LATCH);
+
+	for (i = 0; i < SIRFSOC_TIMER_REG_CNT; i++)
+		sirfsoc_timer_reg_val[i] =
+			readl_relaxed(sirfsoc_timer_base +
+				sirfsoc_timer_reg_list[i]);
+}
+
+static void sirfsoc_clocksource_resume(struct clocksource *cs)
+{
+	int i;
+
+	for (i = 0; i < SIRFSOC_TIMER_REG_CNT - 2; i++)
+		writel_relaxed(sirfsoc_timer_reg_val[i],
+			sirfsoc_timer_base + sirfsoc_timer_reg_list[i]);
+
+	writel_relaxed(sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT - 2],
+		sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_LO);
+	writel_relaxed(sirfsoc_timer_reg_val[SIRFSOC_TIMER_REG_CNT - 1],
+		sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_HI);
+}
+
+static struct clock_event_device sirfsoc_clockevent = {
+	.name = "sirfsoc_clockevent",
+	.rating = 200,
+	.features = CLOCK_EVT_FEAT_ONESHOT,
+	.set_state_shutdown = sirfsoc_timer_shutdown,
+	.set_state_oneshot = sirfsoc_timer_set_oneshot,
+	.set_next_event = sirfsoc_timer_set_next_event,
+};
+
+static struct clocksource sirfsoc_clocksource = {
+	.name = "sirfsoc_clocksource",
+	.rating = 200,
+	.mask = CLOCKSOURCE_MASK(64),
+	.flags = CLOCK_SOURCE_IS_CONTINUOUS,
+	.read = sirfsoc_timer_read,
+	.suspend = sirfsoc_clocksource_suspend,
+	.resume = sirfsoc_clocksource_resume,
+};
+
+static struct irqaction sirfsoc_timer_irq = {
+	.name = "sirfsoc_timer0",
+	.flags = IRQF_TIMER,
+	.irq = 0,
+	.handler = sirfsoc_timer_interrupt,
+	.dev_id = &sirfsoc_clockevent,
+};
+
+/* Overwrite weak default sched_clock with more precise one */
+static u64 notrace sirfsoc_read_sched_clock(void)
+{
+	return sirfsoc_timer_read(NULL);
+}
+
+static void __init sirfsoc_clockevent_init(void)
+{
+	sirfsoc_clockevent.cpumask = cpumask_of(0);
+	clockevents_config_and_register(&sirfsoc_clockevent, PRIMA2_CLOCK_FREQ,
+					2, -2);
+}
+
+/* initialize the kernel jiffy timer source */
+static int __init sirfsoc_prima2_timer_init(struct device_node *np)
+{
+	unsigned long rate;
+	struct clk *clk;
+	int ret;
+
+	clk = of_clk_get(np, 0);
+	if (IS_ERR(clk)) {
+		pr_err("Failed to get clock\n");
+		return PTR_ERR(clk);
+	}
+
+	ret = clk_prepare_enable(clk);
+	if (ret) {
+		pr_err("Failed to enable clock\n");
+		return ret;
+	}
+
+	rate = clk_get_rate(clk);
+
+	if (rate < PRIMA2_CLOCK_FREQ || rate % PRIMA2_CLOCK_FREQ) {
+		pr_err("Invalid clock rate\n");
+		return -EINVAL;
+	}
+
+	sirfsoc_timer_base = of_iomap(np, 0);
+	if (!sirfsoc_timer_base) {
+		pr_err("unable to map timer cpu registers\n");
+		return -ENXIO;
+	}
+
+	sirfsoc_timer_irq.irq = irq_of_parse_and_map(np, 0);
+
+	writel_relaxed(rate / PRIMA2_CLOCK_FREQ / 2 - 1,
+		sirfsoc_timer_base + SIRFSOC_TIMER_DIV);
+	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_LO);
+	writel_relaxed(0, sirfsoc_timer_base + SIRFSOC_TIMER_COUNTER_HI);
+	writel_relaxed(BIT(0), sirfsoc_timer_base + SIRFSOC_TIMER_STATUS);
+
+	ret = clocksource_register_hz(&sirfsoc_clocksource, PRIMA2_CLOCK_FREQ);
+	if (ret) {
+		pr_err("Failed to register clocksource\n");
+		return ret;
+	}
+
+	sched_clock_register(sirfsoc_read_sched_clock, 64, PRIMA2_CLOCK_FREQ);
+
+	ret = setup_irq(sirfsoc_timer_irq.irq, &sirfsoc_timer_irq);
+	if (ret) {
+		pr_err("Failed to setup irq\n");
+		return ret;
+	}
+
+	sirfsoc_clockevent_init();
+
+	return 0;
+}
+TIMER_OF_DECLARE(sirfsoc_prima2_timer,
+	"sirf,prima2-tick", sirfsoc_prima2_timer_init);

drivers/clocksource/timer-probe.c

@@ -0,0 +1,54 @@
+/*
+ * Copyright (c) 2012, NVIDIA CORPORATION.  All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/acpi.h>
+#include <linux/init.h>
+#include <linux/of.h>
+#include <linux/clocksource.h>
+
+extern struct of_device_id __timer_of_table[];
+
+static const struct of_device_id __timer_of_table_sentinel
+	__used __section(__timer_of_table_end);
+
+void __init timer_probe(void)
+{
+	struct device_node *np;
+	const struct of_device_id *match;
+	of_init_fn_1_ret init_func_ret;
+	unsigned timers = 0;
+	int ret;
+
+	for_each_matching_node_and_match(np, __timer_of_table, &match) {
+		if (!of_device_is_available(np))
+			continue;
+
+		init_func_ret = match->data;
+
+		ret = init_func_ret(np);
+		if (ret) {
+			pr_err("Failed to initialize '%pOF': %d\n", np, ret);
+			continue;
+		}
+
+		timers++;
+	}
+
+	timers += acpi_probe_device_table(timer);
+
+	if (!timers)
+		pr_crit("%s: no matching timers found\n", __func__);
+}

drivers/clocksource/timer-sp.h

@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * ARM timer implementation, found in Integrator, Versatile and Realview
+ * platforms.  Not all platforms support all registers and bits in these
+ * registers, so we mark them with A for Integrator AP, C for Integrator
+ * CP, V for Versatile and R for Realview.
+ *
+ * Integrator AP has 16-bit timers, Integrator CP, Versatile and Realview
+ * can have 16-bit or 32-bit selectable via a bit in the control register.
+ *
+ * Every SP804 contains two identical timers.
+ */
+#define TIMER_1_BASE	0x00
+#define TIMER_2_BASE	0x20
+
+#define TIMER_LOAD	0x00			/* ACVR rw */
+#define TIMER_VALUE	0x04			/* ACVR ro */
+#define TIMER_CTRL	0x08			/* ACVR rw */
+#define TIMER_CTRL_ONESHOT	(1 << 0)	/*  CVR */
+#define TIMER_CTRL_32BIT	(1 << 1)	/*  CVR */
+#define TIMER_CTRL_DIV1		(0 << 2)	/* ACVR */
+#define TIMER_CTRL_DIV16	(1 << 2)	/* ACVR */
+#define TIMER_CTRL_DIV256	(2 << 2)	/* ACVR */
+#define TIMER_CTRL_IE		(1 << 5)	/*   VR */
+#define TIMER_CTRL_PERIODIC	(1 << 6)	/* ACVR */
+#define TIMER_CTRL_ENABLE	(1 << 7)	/* ACVR */
+
+#define TIMER_INTCLR	0x0c			/* ACVR wo */
+#define TIMER_RIS	0x10			/*  CVR ro */
+#define TIMER_MIS	0x14			/*  CVR ro */
+#define TIMER_BGLOAD	0x18			/*  CVR rw */

drivers/clocksource/timer-sp804.c

@@ -0,0 +1,339 @@
+/*
+ *  linux/drivers/clocksource/timer-sp.c
+ *
+ *  Copyright (C) 1999 - 2003 ARM Limited
+ *  Copyright (C) 2000 Deep Blue Solutions Ltd
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+#include <linux/clk.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/io.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_clk.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+
+#include <clocksource/timer-sp804.h>
+
+#include "timer-sp.h"
+
+static long __init sp804_get_clock_rate(struct clk *clk)
+{
+	long rate;
+	int err;
+
+	err = clk_prepare(clk);
+	if (err) {
+		pr_err("sp804: clock failed to prepare: %d\n", err);
+		clk_put(clk);
+		return err;
+	}
+
+	err = clk_enable(clk);
+	if (err) {
+		pr_err("sp804: clock failed to enable: %d\n", err);
+		clk_unprepare(clk);
+		clk_put(clk);
+		return err;
+	}
+
+	rate = clk_get_rate(clk);
+	if (rate < 0) {
+		pr_err("sp804: clock failed to get rate: %ld\n", rate);
+		clk_disable(clk);
+		clk_unprepare(clk);
+		clk_put(clk);
+	}
+
+	return rate;
+}
+
+static void __iomem *sched_clock_base;
+
+static u64 notrace sp804_read(void)
+{
+	return ~readl_relaxed(sched_clock_base + TIMER_VALUE);
+}
+
+void __init sp804_timer_disable(void __iomem *base)
+{
+	writel(0, base + TIMER_CTRL);
+}
+
+int  __init __sp804_clocksource_and_sched_clock_init(void __iomem *base,
+						     const char *name,
+						     struct clk *clk,
+						     int use_sched_clock)
+{
+	long rate;
+
+	if (!clk) {
+		clk = clk_get_sys("sp804", name);
+		if (IS_ERR(clk)) {
+			pr_err("sp804: clock not found: %d\n",
+			       (int)PTR_ERR(clk));
+			return PTR_ERR(clk);
+		}
+	}
+
+	rate = sp804_get_clock_rate(clk);
+	if (rate < 0)
+		return -EINVAL;
+
+	/* setup timer 0 as free-running clocksource */
+	writel(0, base + TIMER_CTRL);
+	writel(0xffffffff, base + TIMER_LOAD);
+	writel(0xffffffff, base + TIMER_VALUE);
+	writel(TIMER_CTRL_32BIT | TIMER_CTRL_ENABLE | TIMER_CTRL_PERIODIC,
+		base + TIMER_CTRL);
+
+	clocksource_mmio_init(base + TIMER_VALUE, name,
+		rate, 200, 32, clocksource_mmio_readl_down);
+
+	if (use_sched_clock) {
+		sched_clock_base = base;
+		sched_clock_register(sp804_read, 32, rate);
+	}
+
+	return 0;
+}
+
+
+static void __iomem *clkevt_base;
+static unsigned long clkevt_reload;
+
+/*
+ * IRQ handler for the timer
+ */
+static irqreturn_t sp804_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	/* clear the interrupt */
+	writel(1, clkevt_base + TIMER_INTCLR);
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static inline void timer_shutdown(struct clock_event_device *evt)
+{
+	writel(0, clkevt_base + TIMER_CTRL);
+}
+
+static int sp804_shutdown(struct clock_event_device *evt)
+{
+	timer_shutdown(evt);
+	return 0;
+}
+
+static int sp804_set_periodic(struct clock_event_device *evt)
+{
+	unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE |
+			     TIMER_CTRL_PERIODIC | TIMER_CTRL_ENABLE;
+
+	timer_shutdown(evt);
+	writel(clkevt_reload, clkevt_base + TIMER_LOAD);
+	writel(ctrl, clkevt_base + TIMER_CTRL);
+	return 0;
+}
+
+static int sp804_set_next_event(unsigned long next,
+	struct clock_event_device *evt)
+{
+	unsigned long ctrl = TIMER_CTRL_32BIT | TIMER_CTRL_IE |
+			     TIMER_CTRL_ONESHOT | TIMER_CTRL_ENABLE;
+
+	writel(next, clkevt_base + TIMER_LOAD);
+	writel(ctrl, clkevt_base + TIMER_CTRL);
+
+	return 0;
+}
+
+static struct clock_event_device sp804_clockevent = {
+	.features		= CLOCK_EVT_FEAT_PERIODIC |
+				  CLOCK_EVT_FEAT_ONESHOT |
+				  CLOCK_EVT_FEAT_DYNIRQ,
+	.set_state_shutdown	= sp804_shutdown,
+	.set_state_periodic	= sp804_set_periodic,
+	.set_state_oneshot	= sp804_shutdown,
+	.tick_resume		= sp804_shutdown,
+	.set_next_event		= sp804_set_next_event,
+	.rating			= 300,
+};
+
+static struct irqaction sp804_timer_irq = {
+	.name		= "timer",
+	.flags		= IRQF_TIMER | IRQF_IRQPOLL,
+	.handler	= sp804_timer_interrupt,
+	.dev_id		= &sp804_clockevent,
+};
+
+int __init __sp804_clockevents_init(void __iomem *base, unsigned int irq, struct clk *clk, const char *name)
+{
+	struct clock_event_device *evt = &sp804_clockevent;
+	long rate;
+
+	if (!clk)
+		clk = clk_get_sys("sp804", name);
+	if (IS_ERR(clk)) {
+		pr_err("sp804: %s clock not found: %d\n", name,
+			(int)PTR_ERR(clk));
+		return PTR_ERR(clk);
+	}
+
+	rate = sp804_get_clock_rate(clk);
+	if (rate < 0)
+		return -EINVAL;
+
+	clkevt_base = base;
+	clkevt_reload = DIV_ROUND_CLOSEST(rate, HZ);
+	evt->name = name;
+	evt->irq = irq;
+	evt->cpumask = cpu_possible_mask;
+
+	writel(0, base + TIMER_CTRL);
+
+	setup_irq(irq, &sp804_timer_irq);
+	clockevents_config_and_register(evt, rate, 0xf, 0xffffffff);
+
+	return 0;
+}
+
+static int __init sp804_of_init(struct device_node *np)
+{
+	static bool initialized = false;
+	void __iomem *base;
+	int irq, ret = -EINVAL;
+	u32 irq_num = 0;
+	struct clk *clk1, *clk2;
+	const char *name = of_get_property(np, "compatible", NULL);
+
+	base = of_iomap(np, 0);
+	if (!base)
+		return -ENXIO;
+
+	/* Ensure timers are disabled */
+	writel(0, base + TIMER_CTRL);
+	writel(0, base + TIMER_2_BASE + TIMER_CTRL);
+
+	if (initialized || !of_device_is_available(np)) {
+		ret = -EINVAL;
+		goto err;
+	}
+
+	clk1 = of_clk_get(np, 0);
+	if (IS_ERR(clk1))
+		clk1 = NULL;
+
+	/* Get the 2nd clock if the timer has 3 timer clocks */
+	if (of_clk_get_parent_count(np) == 3) {
+		clk2 = of_clk_get(np, 1);
+		if (IS_ERR(clk2)) {
+			pr_err("sp804: %s clock not found: %d\n", np->name,
+				(int)PTR_ERR(clk2));
+			clk2 = NULL;
+		}
+	} else
+		clk2 = clk1;
+
+	irq = irq_of_parse_and_map(np, 0);
+	if (irq <= 0)
+		goto err;
+
+	of_property_read_u32(np, "arm,sp804-has-irq", &irq_num);
+	if (irq_num == 2) {
+
+		ret = __sp804_clockevents_init(base + TIMER_2_BASE, irq, clk2, name);
+		if (ret)
+			goto err;
+
+		ret = __sp804_clocksource_and_sched_clock_init(base, name, clk1, 1);
+		if (ret)
+			goto err;
+	} else {
+
+		ret = __sp804_clockevents_init(base, irq, clk1 , name);
+		if (ret)
+			goto err;
+
+		ret =__sp804_clocksource_and_sched_clock_init(base + TIMER_2_BASE,
+							      name, clk2, 1);
+		if (ret)
+			goto err;
+	}
+	initialized = true;
+
+	return 0;
+err:
+	iounmap(base);
+	return ret;
+}
+TIMER_OF_DECLARE(sp804, "arm,sp804", sp804_of_init);
+
+static int __init integrator_cp_of_init(struct device_node *np)
+{
+	static int init_count = 0;
+	void __iomem *base;
+	int irq, ret = -EINVAL;
+	const char *name = of_get_property(np, "compatible", NULL);
+	struct clk *clk;
+
+	base = of_iomap(np, 0);
+	if (!base) {
+		pr_err("Failed to iomap\n");
+		return -ENXIO;
+	}
+
+	clk = of_clk_get(np, 0);
+	if (IS_ERR(clk)) {
+		pr_err("Failed to get clock\n");
+		return PTR_ERR(clk);
+	}
+
+	/* Ensure timer is disabled */
+	writel(0, base + TIMER_CTRL);
+
+	if (init_count == 2 || !of_device_is_available(np))
+		goto err;
+
+	if (!init_count) {
+		ret = __sp804_clocksource_and_sched_clock_init(base, name, clk, 0);
+		if (ret)
+			goto err;
+	} else {
+		irq = irq_of_parse_and_map(np, 0);
+		if (irq <= 0)
+			goto err;
+
+		ret = __sp804_clockevents_init(base, irq, clk, name);
+		if (ret)
+			goto err;
+	}
+
+	init_count++;
+	return 0;
+err:
+	iounmap(base);
+	return ret;
+}
+TIMER_OF_DECLARE(intcp, "arm,integrator-cp-timer", integrator_cp_of_init);

drivers/clocksource/timer-sprd.c

@@ -0,0 +1,209 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2017 Spreadtrum Communications Inc.
+ */
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+
+#include "timer-of.h"
+
+#define TIMER_NAME		"sprd_timer"
+
+#define TIMER_LOAD_LO		0x0
+#define TIMER_LOAD_HI		0x4
+#define TIMER_VALUE_LO		0x8
+#define TIMER_VALUE_HI		0xc
+
+#define TIMER_CTL		0x10
+#define TIMER_CTL_PERIOD_MODE	BIT(0)
+#define TIMER_CTL_ENABLE	BIT(1)
+#define TIMER_CTL_64BIT_WIDTH	BIT(16)
+
+#define TIMER_INT		0x14
+#define TIMER_INT_EN		BIT(0)
+#define TIMER_INT_RAW_STS	BIT(1)
+#define TIMER_INT_MASK_STS	BIT(2)
+#define TIMER_INT_CLR		BIT(3)
+
+#define TIMER_VALUE_SHDW_LO	0x18
+#define TIMER_VALUE_SHDW_HI	0x1c
+
+#define TIMER_VALUE_LO_MASK	GENMASK(31, 0)
+
+static void sprd_timer_enable(void __iomem *base, u32 flag)
+{
+	u32 val = readl_relaxed(base + TIMER_CTL);
+
+	val |= TIMER_CTL_ENABLE;
+	if (flag & TIMER_CTL_64BIT_WIDTH)
+		val |= TIMER_CTL_64BIT_WIDTH;
+	else
+		val &= ~TIMER_CTL_64BIT_WIDTH;
+
+	if (flag & TIMER_CTL_PERIOD_MODE)
+		val |= TIMER_CTL_PERIOD_MODE;
+	else
+		val &= ~TIMER_CTL_PERIOD_MODE;
+
+	writel_relaxed(val, base + TIMER_CTL);
+}
+
+static void sprd_timer_disable(void __iomem *base)
+{
+	u32 val = readl_relaxed(base + TIMER_CTL);
+
+	val &= ~TIMER_CTL_ENABLE;
+	writel_relaxed(val, base + TIMER_CTL);
+}
+
+static void sprd_timer_update_counter(void __iomem *base, unsigned long cycles)
+{
+	writel_relaxed(cycles & TIMER_VALUE_LO_MASK, base + TIMER_LOAD_LO);
+	writel_relaxed(0, base + TIMER_LOAD_HI);
+}
+
+static void sprd_timer_enable_interrupt(void __iomem *base)
+{
+	writel_relaxed(TIMER_INT_EN, base + TIMER_INT);
+}
+
+static void sprd_timer_clear_interrupt(void __iomem *base)
+{
+	u32 val = readl_relaxed(base + TIMER_INT);
+
+	val |= TIMER_INT_CLR;
+	writel_relaxed(val, base + TIMER_INT);
+}
+
+static int sprd_timer_set_next_event(unsigned long cycles,
+				     struct clock_event_device *ce)
+{
+	struct timer_of *to = to_timer_of(ce);
+
+	sprd_timer_disable(timer_of_base(to));
+	sprd_timer_update_counter(timer_of_base(to), cycles);
+	sprd_timer_enable(timer_of_base(to), 0);
+
+	return 0;
+}
+
+static int sprd_timer_set_periodic(struct clock_event_device *ce)
+{
+	struct timer_of *to = to_timer_of(ce);
+
+	sprd_timer_disable(timer_of_base(to));
+	sprd_timer_update_counter(timer_of_base(to), timer_of_period(to));
+	sprd_timer_enable(timer_of_base(to), TIMER_CTL_PERIOD_MODE);
+
+	return 0;
+}
+
+static int sprd_timer_shutdown(struct clock_event_device *ce)
+{
+	struct timer_of *to = to_timer_of(ce);
+
+	sprd_timer_disable(timer_of_base(to));
+	return 0;
+}
+
+static irqreturn_t sprd_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *ce = (struct clock_event_device *)dev_id;
+	struct timer_of *to = to_timer_of(ce);
+
+	sprd_timer_clear_interrupt(timer_of_base(to));
+
+	if (clockevent_state_oneshot(ce))
+		sprd_timer_disable(timer_of_base(to));
+
+	ce->event_handler(ce);
+	return IRQ_HANDLED;
+}
+
+static struct timer_of to = {
+	.flags = TIMER_OF_IRQ | TIMER_OF_BASE | TIMER_OF_CLOCK,
+
+	.clkevt = {
+		.name = TIMER_NAME,
+		.rating = 300,
+		.features = CLOCK_EVT_FEAT_DYNIRQ | CLOCK_EVT_FEAT_PERIODIC |
+			CLOCK_EVT_FEAT_ONESHOT,
+		.set_state_shutdown = sprd_timer_shutdown,
+		.set_state_periodic = sprd_timer_set_periodic,
+		.set_next_event = sprd_timer_set_next_event,
+		.cpumask = cpu_possible_mask,
+	},
+
+	.of_irq = {
+		.handler = sprd_timer_interrupt,
+		.flags = IRQF_TIMER | IRQF_IRQPOLL,
+	},
+};
+
+static int __init sprd_timer_init(struct device_node *np)
+{
+	int ret;
+
+	ret = timer_of_init(np, &to);
+	if (ret)
+		return ret;
+
+	sprd_timer_enable_interrupt(timer_of_base(&to));
+	clockevents_config_and_register(&to.clkevt, timer_of_rate(&to),
+					1, UINT_MAX);
+
+	return 0;
+}
+
+static struct timer_of suspend_to = {
+	.flags = TIMER_OF_BASE | TIMER_OF_CLOCK,
+};
+
+static u64 sprd_suspend_timer_read(struct clocksource *cs)
+{
+	return ~(u64)readl_relaxed(timer_of_base(&suspend_to) +
+				   TIMER_VALUE_SHDW_LO) & cs->mask;
+}
+
+static int sprd_suspend_timer_enable(struct clocksource *cs)
+{
+	sprd_timer_update_counter(timer_of_base(&suspend_to),
+				  TIMER_VALUE_LO_MASK);
+	sprd_timer_enable(timer_of_base(&suspend_to), TIMER_CTL_PERIOD_MODE);
+
+	return 0;
+}
+
+static void sprd_suspend_timer_disable(struct clocksource *cs)
+{
+	sprd_timer_disable(timer_of_base(&suspend_to));
+}
+
+static struct clocksource suspend_clocksource = {
+	.name	= "sprd_suspend_timer",
+	.rating	= 200,
+	.read	= sprd_suspend_timer_read,
+	.enable = sprd_suspend_timer_enable,
+	.disable = sprd_suspend_timer_disable,
+	.mask	= CLOCKSOURCE_MASK(32),
+	.flags	= CLOCK_SOURCE_IS_CONTINUOUS | CLOCK_SOURCE_SUSPEND_NONSTOP,
+};
+
+static int __init sprd_suspend_timer_init(struct device_node *np)
+{
+	int ret;
+
+	ret = timer_of_init(np, &suspend_to);
+	if (ret)
+		return ret;
+
+	clocksource_register_hz(&suspend_clocksource,
+				timer_of_rate(&suspend_to));
+
+	return 0;
+}
+
+TIMER_OF_DECLARE(sc9860_timer, "sprd,sc9860-timer", sprd_timer_init);
+TIMER_OF_DECLARE(sc9860_persistent_timer, "sprd,sc9860-suspend-timer",
+		 sprd_suspend_timer_init);

drivers/clocksource/timer-stm32.c

@@ -0,0 +1,336 @@
+/*
+ * Copyright (C) Maxime Coquelin 2015
+ * Author:  Maxime Coquelin <mcoquelin.stm32@gmail.com>
+ * License terms:  GNU General Public License (GPL), version 2
+ *
+ * Inspired by time-efm32.c from Uwe Kleine-Koenig
+ */
+
+#include <linux/kernel.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/delay.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/clk.h>
+#include <linux/reset.h>
+#include <linux/sched_clock.h>
+#include <linux/slab.h>
+
+#include "timer-of.h"
+
+#define TIM_CR1		0x00
+#define TIM_DIER	0x0c
+#define TIM_SR		0x10
+#define TIM_EGR		0x14
+#define TIM_CNT		0x24
+#define TIM_PSC		0x28
+#define TIM_ARR		0x2c
+#define TIM_CCR1	0x34
+
+#define TIM_CR1_CEN	BIT(0)
+#define TIM_CR1_UDIS	BIT(1)
+#define TIM_CR1_OPM	BIT(3)
+#define TIM_CR1_ARPE	BIT(7)
+
+#define TIM_DIER_UIE	BIT(0)
+#define TIM_DIER_CC1IE	BIT(1)
+
+#define TIM_SR_UIF	BIT(0)
+
+#define TIM_EGR_UG	BIT(0)
+
+#define TIM_PSC_MAX	USHRT_MAX
+#define TIM_PSC_CLKRATE	10000
+
+struct stm32_timer_private {
+	int bits;
+};
+
+/**
+ * stm32_timer_of_bits_set - set accessor helper
+ * @to: a timer_of structure pointer
+ * @bits: the number of bits (16 or 32)
+ *
+ * Accessor helper to set the number of bits in the timer-of private
+ * structure.
+ *
+ */
+static void stm32_timer_of_bits_set(struct timer_of *to, int bits)
+{
+	struct stm32_timer_private *pd = to->private_data;
+
+	pd->bits = bits;
+}
+
+/**
+ * stm32_timer_of_bits_get - get accessor helper
+ * @to: a timer_of structure pointer
+ *
+ * Accessor helper to get the number of bits in the timer-of private
+ * structure.
+ *
+ * Returns an integer corresponding to the number of bits.
+ */
+static int stm32_timer_of_bits_get(struct timer_of *to)
+{
+	struct stm32_timer_private *pd = to->private_data;
+
+	return pd->bits;
+}
+
+static void __iomem *stm32_timer_cnt __read_mostly;
+
+static u64 notrace stm32_read_sched_clock(void)
+{
+	return readl_relaxed(stm32_timer_cnt);
+}
+
+static struct delay_timer stm32_timer_delay;
+
+static unsigned long stm32_read_delay(void)
+{
+	return readl_relaxed(stm32_timer_cnt);
+}
+
+static void stm32_clock_event_disable(struct timer_of *to)
+{
+	writel_relaxed(0, timer_of_base(to) + TIM_DIER);
+}
+
+/**
+ * stm32_timer_start - Start the counter without event
+ * @to: a timer_of structure pointer
+ *
+ * Start the timer in order to have the counter reset and start
+ * incrementing but disable interrupt event when there is a counter
+ * overflow. By default, the counter direction is used as upcounter.
+ */
+static void stm32_timer_start(struct timer_of *to)
+{
+	writel_relaxed(TIM_CR1_UDIS | TIM_CR1_CEN, timer_of_base(to) + TIM_CR1);
+}
+
+static int stm32_clock_event_shutdown(struct clock_event_device *clkevt)
+{
+	struct timer_of *to = to_timer_of(clkevt);
+
+	stm32_clock_event_disable(to);
+
+	return 0;
+}
+
+static int stm32_clock_event_set_next_event(unsigned long evt,
+					    struct clock_event_device *clkevt)
+{
+	struct timer_of *to = to_timer_of(clkevt);
+	unsigned long now, next;
+
+	next = readl_relaxed(timer_of_base(to) + TIM_CNT) + evt;
+	writel_relaxed(next, timer_of_base(to) + TIM_CCR1);
+	now = readl_relaxed(timer_of_base(to) + TIM_CNT);
+
+	if ((next - now) > evt)
+		return -ETIME;
+
+	writel_relaxed(TIM_DIER_CC1IE, timer_of_base(to) + TIM_DIER);
+
+	return 0;
+}
+
+static int stm32_clock_event_set_periodic(struct clock_event_device *clkevt)
+{
+	struct timer_of *to = to_timer_of(clkevt);
+
+	stm32_timer_start(to);
+
+	return stm32_clock_event_set_next_event(timer_of_period(to), clkevt);
+}
+
+static int stm32_clock_event_set_oneshot(struct clock_event_device *clkevt)
+{
+	struct timer_of *to = to_timer_of(clkevt);
+
+	stm32_timer_start(to);
+
+	return 0;
+}
+
+static irqreturn_t stm32_clock_event_handler(int irq, void *dev_id)
+{
+	struct clock_event_device *clkevt = (struct clock_event_device *)dev_id;
+	struct timer_of *to = to_timer_of(clkevt);
+
+	writel_relaxed(0, timer_of_base(to) + TIM_SR);
+
+	if (clockevent_state_periodic(clkevt))
+		stm32_clock_event_set_periodic(clkevt);
+	else
+		stm32_clock_event_shutdown(clkevt);
+
+	clkevt->event_handler(clkevt);
+
+	return IRQ_HANDLED;
+}
+
+/**
+ * stm32_timer_width - Sort out the timer width (32/16)
+ * @to: a pointer to a timer-of structure
+ *
+ * Write the 32-bit max value and read/return the result. If the timer
+ * is 32 bits wide, the result will be UINT_MAX, otherwise it will
+ * be truncated by the 16-bit register to USHRT_MAX.
+ *
+ */
+static void __init stm32_timer_set_width(struct timer_of *to)
+{
+	u32 width;
+
+	writel_relaxed(UINT_MAX, timer_of_base(to) + TIM_ARR);
+
+	width = readl_relaxed(timer_of_base(to) + TIM_ARR);
+
+	stm32_timer_of_bits_set(to, width == UINT_MAX ? 32 : 16);
+}
+
+/**
+ * stm32_timer_set_prescaler - Compute and set the prescaler register
+ * @to: a pointer to a timer-of structure
+ *
+ * Depending on the timer width, compute the prescaler to always
+ * target a 10MHz timer rate for 16 bits. 32-bit timers are
+ * considered precise and long enough to not use the prescaler.
+ */
+static void __init stm32_timer_set_prescaler(struct timer_of *to)
+{
+	int prescaler = 1;
+
+	if (stm32_timer_of_bits_get(to) != 32) {
+		prescaler = DIV_ROUND_CLOSEST(timer_of_rate(to),
+					      TIM_PSC_CLKRATE);
+		/*
+		 * The prescaler register is an u16, the variable
+		 * can't be greater than TIM_PSC_MAX, let's cap it in
+		 * this case.
+		 */
+		prescaler = prescaler < TIM_PSC_MAX ? prescaler : TIM_PSC_MAX;
+	}
+
+	writel_relaxed(prescaler - 1, timer_of_base(to) + TIM_PSC);
+	writel_relaxed(TIM_EGR_UG, timer_of_base(to) + TIM_EGR);
+	writel_relaxed(0, timer_of_base(to) + TIM_SR);
+
+	/* Adjust rate and period given the prescaler value */
+	to->of_clk.rate = DIV_ROUND_CLOSEST(to->of_clk.rate, prescaler);
+	to->of_clk.period = DIV_ROUND_UP(to->of_clk.rate, HZ);
+}
+
+static int __init stm32_clocksource_init(struct timer_of *to)
+{
+        u32 bits = stm32_timer_of_bits_get(to);
+	const char *name = to->np->full_name;
+
+	/*
+	 * This driver allows to register several timers and relies on
+	 * the generic time framework to select the right one.
+	 * However, nothing allows to do the same for the
+	 * sched_clock. We are not interested in a sched_clock for the
+	 * 16-bit timers but only for the 32-bit one, so if no 32-bit
+	 * timer is registered yet, we select this 32-bit timer as a
+	 * sched_clock.
+	 */
+	if (bits == 32 && !stm32_timer_cnt) {
+
+		/*
+		 * Start immediately the counter as we will be using
+		 * it right after.
+		 */
+		stm32_timer_start(to);
+
+		stm32_timer_cnt = timer_of_base(to) + TIM_CNT;
+		sched_clock_register(stm32_read_sched_clock, bits, timer_of_rate(to));
+		pr_info("%s: STM32 sched_clock registered\n", name);
+
+		stm32_timer_delay.read_current_timer = stm32_read_delay;
+		stm32_timer_delay.freq = timer_of_rate(to);
+		register_current_timer_delay(&stm32_timer_delay);
+		pr_info("%s: STM32 delay timer registered\n", name);
+	}
+
+	return clocksource_mmio_init(timer_of_base(to) + TIM_CNT, name,
+				     timer_of_rate(to), bits == 32 ? 250 : 100,
+				     bits, clocksource_mmio_readl_up);
+}
+
+static void __init stm32_clockevent_init(struct timer_of *to)
+{
+	u32 bits = stm32_timer_of_bits_get(to);
+
+	to->clkevt.name = to->np->full_name;
+	to->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
+	to->clkevt.set_state_shutdown = stm32_clock_event_shutdown;
+	to->clkevt.set_state_periodic = stm32_clock_event_set_periodic;
+	to->clkevt.set_state_oneshot = stm32_clock_event_set_oneshot;
+	to->clkevt.tick_resume = stm32_clock_event_shutdown;
+	to->clkevt.set_next_event = stm32_clock_event_set_next_event;
+	to->clkevt.rating = bits == 32 ? 250 : 100;
+
+	clockevents_config_and_register(&to->clkevt, timer_of_rate(to), 0x1,
+					(1 <<  bits) - 1);
+
+	pr_info("%pOF: STM32 clockevent driver initialized (%d bits)\n",
+		to->np, bits);
+}
+
+static int __init stm32_timer_init(struct device_node *node)
+{
+	struct reset_control *rstc;
+	struct timer_of *to;
+	int ret;
+
+	to = kzalloc(sizeof(*to), GFP_KERNEL);
+	if (!to)
+		return -ENOMEM;
+
+	to->flags = TIMER_OF_IRQ | TIMER_OF_CLOCK | TIMER_OF_BASE;
+	to->of_irq.handler = stm32_clock_event_handler;
+
+	ret = timer_of_init(node, to);
+	if (ret)
+		goto err;
+
+	to->private_data = kzalloc(sizeof(struct stm32_timer_private),
+				   GFP_KERNEL);
+	if (!to->private_data) {
+		ret = -ENOMEM;
+		goto deinit;
+	}
+
+	rstc = of_reset_control_get(node, NULL);
+	if (!IS_ERR(rstc)) {
+		reset_control_assert(rstc);
+		reset_control_deassert(rstc);
+	}
+
+	stm32_timer_set_width(to);
+
+	stm32_timer_set_prescaler(to);
+
+	ret = stm32_clocksource_init(to);
+	if (ret)
+		goto deinit;
+
+	stm32_clockevent_init(to);
+	return 0;
+
+deinit:
+	timer_of_cleanup(to);
+err:
+	kfree(to);
+	return ret;
+}
+
+TIMER_OF_DECLARE(stm32, "st,stm32-timer", stm32_timer_init);

drivers/clocksource/timer-sun5i.c

@@ -0,0 +1,375 @@
+/*
+ * Allwinner SoCs hstimer driver.
+ *
+ * Copyright (C) 2013 Maxime Ripard
+ *
+ * Maxime Ripard <maxime.ripard@free-electrons.com>
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.  This program is licensed "as is" without any
+ * warranty of any kind, whether express or implied.
+ */
+
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/delay.h>
+#include <linux/interrupt.h>
+#include <linux/irq.h>
+#include <linux/irqreturn.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define TIMER_IRQ_EN_REG		0x00
+#define TIMER_IRQ_EN(val)			BIT(val)
+#define TIMER_IRQ_ST_REG		0x04
+#define TIMER_CTL_REG(val)		(0x20 * (val) + 0x10)
+#define TIMER_CTL_ENABLE			BIT(0)
+#define TIMER_CTL_RELOAD			BIT(1)
+#define TIMER_CTL_CLK_PRES(val)			(((val) & 0x7) << 4)
+#define TIMER_CTL_ONESHOT			BIT(7)
+#define TIMER_INTVAL_LO_REG(val)	(0x20 * (val) + 0x14)
+#define TIMER_INTVAL_HI_REG(val)	(0x20 * (val) + 0x18)
+#define TIMER_CNTVAL_LO_REG(val)	(0x20 * (val) + 0x1c)
+#define TIMER_CNTVAL_HI_REG(val)	(0x20 * (val) + 0x20)
+
+#define TIMER_SYNC_TICKS	3
+
+struct sun5i_timer {
+	void __iomem		*base;
+	struct clk		*clk;
+	struct notifier_block	clk_rate_cb;
+	u32			ticks_per_jiffy;
+};
+
+#define to_sun5i_timer(x) \
+	container_of(x, struct sun5i_timer, clk_rate_cb)
+
+struct sun5i_timer_clksrc {
+	struct sun5i_timer	timer;
+	struct clocksource	clksrc;
+};
+
+#define to_sun5i_timer_clksrc(x) \
+	container_of(x, struct sun5i_timer_clksrc, clksrc)
+
+struct sun5i_timer_clkevt {
+	struct sun5i_timer		timer;
+	struct clock_event_device	clkevt;
+};
+
+#define to_sun5i_timer_clkevt(x) \
+	container_of(x, struct sun5i_timer_clkevt, clkevt)
+
+/*
+ * When we disable a timer, we need to wait at least for 2 cycles of
+ * the timer source clock. We will use for that the clocksource timer
+ * that is already setup and runs at the same frequency than the other
+ * timers, and we never will be disabled.
+ */
+static void sun5i_clkevt_sync(struct sun5i_timer_clkevt *ce)
+{
+	u32 old = readl(ce->timer.base + TIMER_CNTVAL_LO_REG(1));
+
+	while ((old - readl(ce->timer.base + TIMER_CNTVAL_LO_REG(1))) < TIMER_SYNC_TICKS)
+		cpu_relax();
+}
+
+static void sun5i_clkevt_time_stop(struct sun5i_timer_clkevt *ce, u8 timer)
+{
+	u32 val = readl(ce->timer.base + TIMER_CTL_REG(timer));
+	writel(val & ~TIMER_CTL_ENABLE, ce->timer.base + TIMER_CTL_REG(timer));
+
+	sun5i_clkevt_sync(ce);
+}
+
+static void sun5i_clkevt_time_setup(struct sun5i_timer_clkevt *ce, u8 timer, u32 delay)
+{
+	writel(delay, ce->timer.base + TIMER_INTVAL_LO_REG(timer));
+}
+
+static void sun5i_clkevt_time_start(struct sun5i_timer_clkevt *ce, u8 timer, bool periodic)
+{
+	u32 val = readl(ce->timer.base + TIMER_CTL_REG(timer));
+
+	if (periodic)
+		val &= ~TIMER_CTL_ONESHOT;
+	else
+		val |= TIMER_CTL_ONESHOT;
+
+	writel(val | TIMER_CTL_ENABLE | TIMER_CTL_RELOAD,
+	       ce->timer.base + TIMER_CTL_REG(timer));
+}
+
+static int sun5i_clkevt_shutdown(struct clock_event_device *clkevt)
+{
+	struct sun5i_timer_clkevt *ce = to_sun5i_timer_clkevt(clkevt);
+
+	sun5i_clkevt_time_stop(ce, 0);
+	return 0;
+}
+
+static int sun5i_clkevt_set_oneshot(struct clock_event_device *clkevt)
+{
+	struct sun5i_timer_clkevt *ce = to_sun5i_timer_clkevt(clkevt);
+
+	sun5i_clkevt_time_stop(ce, 0);
+	sun5i_clkevt_time_start(ce, 0, false);
+	return 0;
+}
+
+static int sun5i_clkevt_set_periodic(struct clock_event_device *clkevt)
+{
+	struct sun5i_timer_clkevt *ce = to_sun5i_timer_clkevt(clkevt);
+
+	sun5i_clkevt_time_stop(ce, 0);
+	sun5i_clkevt_time_setup(ce, 0, ce->timer.ticks_per_jiffy);
+	sun5i_clkevt_time_start(ce, 0, true);
+	return 0;
+}
+
+static int sun5i_clkevt_next_event(unsigned long evt,
+				   struct clock_event_device *clkevt)
+{
+	struct sun5i_timer_clkevt *ce = to_sun5i_timer_clkevt(clkevt);
+
+	sun5i_clkevt_time_stop(ce, 0);
+	sun5i_clkevt_time_setup(ce, 0, evt - TIMER_SYNC_TICKS);
+	sun5i_clkevt_time_start(ce, 0, false);
+
+	return 0;
+}
+
+static irqreturn_t sun5i_timer_interrupt(int irq, void *dev_id)
+{
+	struct sun5i_timer_clkevt *ce = (struct sun5i_timer_clkevt *)dev_id;
+
+	writel(0x1, ce->timer.base + TIMER_IRQ_ST_REG);
+	ce->clkevt.event_handler(&ce->clkevt);
+
+	return IRQ_HANDLED;
+}
+
+static u64 sun5i_clksrc_read(struct clocksource *clksrc)
+{
+	struct sun5i_timer_clksrc *cs = to_sun5i_timer_clksrc(clksrc);
+
+	return ~readl(cs->timer.base + TIMER_CNTVAL_LO_REG(1));
+}
+
+static int sun5i_rate_cb_clksrc(struct notifier_block *nb,
+				unsigned long event, void *data)
+{
+	struct clk_notifier_data *ndata = data;
+	struct sun5i_timer *timer = to_sun5i_timer(nb);
+	struct sun5i_timer_clksrc *cs = container_of(timer, struct sun5i_timer_clksrc, timer);
+
+	switch (event) {
+	case PRE_RATE_CHANGE:
+		clocksource_unregister(&cs->clksrc);
+		break;
+
+	case POST_RATE_CHANGE:
+		clocksource_register_hz(&cs->clksrc, ndata->new_rate);
+		break;
+
+	default:
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
+static int __init sun5i_setup_clocksource(struct device_node *node,
+					  void __iomem *base,
+					  struct clk *clk, int irq)
+{
+	struct sun5i_timer_clksrc *cs;
+	unsigned long rate;
+	int ret;
+
+	cs = kzalloc(sizeof(*cs), GFP_KERNEL);
+	if (!cs)
+		return -ENOMEM;
+
+	ret = clk_prepare_enable(clk);
+	if (ret) {
+		pr_err("Couldn't enable parent clock\n");
+		goto err_free;
+	}
+
+	rate = clk_get_rate(clk);
+	if (!rate) {
+		pr_err("Couldn't get parent clock rate\n");
+		ret = -EINVAL;
+		goto err_disable_clk;
+	}
+
+	cs->timer.base = base;
+	cs->timer.clk = clk;
+	cs->timer.clk_rate_cb.notifier_call = sun5i_rate_cb_clksrc;
+	cs->timer.clk_rate_cb.next = NULL;
+
+	ret = clk_notifier_register(clk, &cs->timer.clk_rate_cb);
+	if (ret) {
+		pr_err("Unable to register clock notifier.\n");
+		goto err_disable_clk;
+	}
+
+	writel(~0, base + TIMER_INTVAL_LO_REG(1));
+	writel(TIMER_CTL_ENABLE | TIMER_CTL_RELOAD,
+	       base + TIMER_CTL_REG(1));
+
+	cs->clksrc.name = node->name;
+	cs->clksrc.rating = 340;
+	cs->clksrc.read = sun5i_clksrc_read;
+	cs->clksrc.mask = CLOCKSOURCE_MASK(32);
+	cs->clksrc.flags = CLOCK_SOURCE_IS_CONTINUOUS;
+
+	ret = clocksource_register_hz(&cs->clksrc, rate);
+	if (ret) {
+		pr_err("Couldn't register clock source.\n");
+		goto err_remove_notifier;
+	}
+
+	return 0;
+
+err_remove_notifier:
+	clk_notifier_unregister(clk, &cs->timer.clk_rate_cb);
+err_disable_clk:
+	clk_disable_unprepare(clk);
+err_free:
+	kfree(cs);
+	return ret;
+}
+
+static int sun5i_rate_cb_clkevt(struct notifier_block *nb,
+				unsigned long event, void *data)
+{
+	struct clk_notifier_data *ndata = data;
+	struct sun5i_timer *timer = to_sun5i_timer(nb);
+	struct sun5i_timer_clkevt *ce = container_of(timer, struct sun5i_timer_clkevt, timer);
+
+	if (event == POST_RATE_CHANGE) {
+		clockevents_update_freq(&ce->clkevt, ndata->new_rate);
+		ce->timer.ticks_per_jiffy = DIV_ROUND_UP(ndata->new_rate, HZ);
+	}
+
+	return NOTIFY_DONE;
+}
+
+static int __init sun5i_setup_clockevent(struct device_node *node, void __iomem *base,
+					 struct clk *clk, int irq)
+{
+	struct sun5i_timer_clkevt *ce;
+	unsigned long rate;
+	int ret;
+	u32 val;
+
+	ce = kzalloc(sizeof(*ce), GFP_KERNEL);
+	if (!ce)
+		return -ENOMEM;
+
+	ret = clk_prepare_enable(clk);
+	if (ret) {
+		pr_err("Couldn't enable parent clock\n");
+		goto err_free;
+	}
+
+	rate = clk_get_rate(clk);
+	if (!rate) {
+		pr_err("Couldn't get parent clock rate\n");
+		ret = -EINVAL;
+		goto err_disable_clk;
+	}
+
+	ce->timer.base = base;
+	ce->timer.ticks_per_jiffy = DIV_ROUND_UP(rate, HZ);
+	ce->timer.clk = clk;
+	ce->timer.clk_rate_cb.notifier_call = sun5i_rate_cb_clkevt;
+	ce->timer.clk_rate_cb.next = NULL;
+
+	ret = clk_notifier_register(clk, &ce->timer.clk_rate_cb);
+	if (ret) {
+		pr_err("Unable to register clock notifier.\n");
+		goto err_disable_clk;
+	}
+
+	ce->clkevt.name = node->name;
+	ce->clkevt.features = CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT;
+	ce->clkevt.set_next_event = sun5i_clkevt_next_event;
+	ce->clkevt.set_state_shutdown = sun5i_clkevt_shutdown;
+	ce->clkevt.set_state_periodic = sun5i_clkevt_set_periodic;
+	ce->clkevt.set_state_oneshot = sun5i_clkevt_set_oneshot;
+	ce->clkevt.tick_resume = sun5i_clkevt_shutdown;
+	ce->clkevt.rating = 340;
+	ce->clkevt.irq = irq;
+	ce->clkevt.cpumask = cpu_possible_mask;
+
+	/* Enable timer0 interrupt */
+	val = readl(base + TIMER_IRQ_EN_REG);
+	writel(val | TIMER_IRQ_EN(0), base + TIMER_IRQ_EN_REG);
+
+	clockevents_config_and_register(&ce->clkevt, rate,
+					TIMER_SYNC_TICKS, 0xffffffff);
+
+	ret = request_irq(irq, sun5i_timer_interrupt, IRQF_TIMER | IRQF_IRQPOLL,
+			  "sun5i_timer0", ce);
+	if (ret) {
+		pr_err("Unable to register interrupt\n");
+		goto err_remove_notifier;
+	}
+
+	return 0;
+
+err_remove_notifier:
+	clk_notifier_unregister(clk, &ce->timer.clk_rate_cb);
+err_disable_clk:
+	clk_disable_unprepare(clk);
+err_free:
+	kfree(ce);
+	return ret;
+}
+
+static int __init sun5i_timer_init(struct device_node *node)
+{
+	struct reset_control *rstc;
+	void __iomem *timer_base;
+	struct clk *clk;
+	int irq, ret;
+
+	timer_base = of_io_request_and_map(node, 0, of_node_full_name(node));
+	if (IS_ERR(timer_base)) {
+		pr_err("Can't map registers\n");
+		return PTR_ERR(timer_base);
+	}
+
+	irq = irq_of_parse_and_map(node, 0);
+	if (irq <= 0) {
+		pr_err("Can't parse IRQ\n");
+		return -EINVAL;
+	}
+
+	clk = of_clk_get(node, 0);
+	if (IS_ERR(clk)) {
+		pr_err("Can't get timer clock\n");
+		return PTR_ERR(clk);
+	}
+
+	rstc = of_reset_control_get(node, NULL);
+	if (!IS_ERR(rstc))
+		reset_control_deassert(rstc);
+
+	ret = sun5i_setup_clocksource(node, timer_base, clk, irq);
+	if (ret)
+		return ret;
+
+	return sun5i_setup_clockevent(node, timer_base, clk, irq);
+}
+TIMER_OF_DECLARE(sun5i_a13, "allwinner,sun5i-a13-hstimer",
+			   sun5i_timer_init);
+TIMER_OF_DECLARE(sun7i_a20, "allwinner,sun7i-a20-hstimer",
+			   sun5i_timer_init);

drivers/clocksource/timer-ti-32k.c

@@ -0,0 +1,130 @@
+/**
+ * timer-ti-32k.c - OMAP2 32k Timer Support
+ *
+ * Copyright (C) 2009 Nokia Corporation
+ *
+ * Update to use new clocksource/clockevent layers
+ * Author: Kevin Hilman, MontaVista Software, Inc. <source@mvista.com>
+ * Copyright (C) 2007 MontaVista Software, Inc.
+ *
+ * Original driver:
+ * Copyright (C) 2005 Nokia Corporation
+ * Author: Paul Mundt <paul.mundt@nokia.com>
+ *         Juha Yrjölä <juha.yrjola@nokia.com>
+ * OMAP Dual-mode timer framework support by Timo Teras
+ *
+ * Some parts based off of TI's 24xx code:
+ *
+ * Copyright (C) 2004-2009 Texas Instruments, Inc.
+ *
+ * Roughly modelled after the OMAP1 MPU timer code.
+ * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com>
+ *
+ * Copyright (C) 2015 Texas Instruments Incorporated - http://www.ti.com
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2  of
+ * the License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <linux/init.h>
+#include <linux/time.h>
+#include <linux/sched_clock.h>
+#include <linux/clocksource.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+
+/*
+ * 32KHz clocksource ... always available, on pretty most chips except
+ * OMAP 730 and 1510.  Other timers could be used as clocksources, with
+ * higher resolution in free-running counter modes (e.g. 12 MHz xtal),
+ * but systems won't necessarily want to spend resources that way.
+ */
+
+#define OMAP2_32KSYNCNT_REV_OFF		0x0
+#define OMAP2_32KSYNCNT_REV_SCHEME	(0x3 << 30)
+#define OMAP2_32KSYNCNT_CR_OFF_LOW	0x10
+#define OMAP2_32KSYNCNT_CR_OFF_HIGH	0x30
+
+struct ti_32k {
+	void __iomem		*base;
+	void __iomem		*counter;
+	struct clocksource	cs;
+};
+
+static inline struct ti_32k *to_ti_32k(struct clocksource *cs)
+{
+	return container_of(cs, struct ti_32k, cs);
+}
+
+static u64 notrace ti_32k_read_cycles(struct clocksource *cs)
+{
+	struct ti_32k *ti = to_ti_32k(cs);
+
+	return (u64)readl_relaxed(ti->counter);
+}
+
+static struct ti_32k ti_32k_timer = {
+	.cs = {
+		.name		= "32k_counter",
+		.rating		= 250,
+		.read		= ti_32k_read_cycles,
+		.mask		= CLOCKSOURCE_MASK(32),
+		.flags		= CLOCK_SOURCE_IS_CONTINUOUS,
+	},
+};
+
+static u64 notrace omap_32k_read_sched_clock(void)
+{
+	return ti_32k_read_cycles(&ti_32k_timer.cs);
+}
+
+static int __init ti_32k_timer_init(struct device_node *np)
+{
+	int ret;
+
+	ti_32k_timer.base = of_iomap(np, 0);
+	if (!ti_32k_timer.base) {
+		pr_err("Can't ioremap 32k timer base\n");
+		return -ENXIO;
+	}
+
+	if (!of_machine_is_compatible("ti,am43"))
+		ti_32k_timer.cs.flags |= CLOCK_SOURCE_SUSPEND_NONSTOP;
+
+	ti_32k_timer.counter = ti_32k_timer.base;
+
+	/*
+	 * 32k sync Counter IP register offsets vary between the highlander
+	 * version and the legacy ones.
+	 *
+	 * The 'SCHEME' bits(30-31) of the revision register is used to identify
+	 * the version.
+	 */
+	if (readl_relaxed(ti_32k_timer.base + OMAP2_32KSYNCNT_REV_OFF) &
+			OMAP2_32KSYNCNT_REV_SCHEME)
+		ti_32k_timer.counter += OMAP2_32KSYNCNT_CR_OFF_HIGH;
+	else
+		ti_32k_timer.counter += OMAP2_32KSYNCNT_CR_OFF_LOW;
+
+	ret = clocksource_register_hz(&ti_32k_timer.cs, 32768);
+	if (ret) {
+		pr_err("32k_counter: can't register clocksource\n");
+		return ret;
+	}
+
+	sched_clock_register(omap_32k_read_sched_clock, 32, 32768);
+	pr_info("OMAP clocksource: 32k_counter at 32768 Hz\n");
+
+	return 0;
+}
+TIMER_OF_DECLARE(ti_32k_timer, "ti,omap-counter32k",
+		ti_32k_timer_init);

drivers/clocksource/timer-u300.c

@@ -0,0 +1,462 @@
+/*
+ * Copyright (C) 2007-2009 ST-Ericsson AB
+ * License terms: GNU General Public License (GPL) version 2
+ * Timer COH 901 328, runs the OS timer interrupt.
+ * Author: Linus Walleij <linus.walleij@stericsson.com>
+ */
+#include <linux/interrupt.h>
+#include <linux/time.h>
+#include <linux/timex.h>
+#include <linux/clockchips.h>
+#include <linux/clocksource.h>
+#include <linux/types.h>
+#include <linux/io.h>
+#include <linux/clk.h>
+#include <linux/err.h>
+#include <linux/irq.h>
+#include <linux/delay.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+
+/* Generic stuff */
+#include <asm/mach/map.h>
+#include <asm/mach/time.h>
+
+/*
+ * APP side special timer registers
+ * This timer contains four timers which can fire an interrupt each.
+ * OS (operating system) timer @ 32768 Hz
+ * DD (device driver) timer @ 1 kHz
+ * GP1 (general purpose 1) timer @ 1MHz
+ * GP2 (general purpose 2) timer @ 1MHz
+ */
+
+/* Reset OS Timer 32bit (-/W) */
+#define U300_TIMER_APP_ROST					(0x0000)
+#define U300_TIMER_APP_ROST_TIMER_RESET				(0x00000000)
+/* Enable OS Timer 32bit (-/W) */
+#define U300_TIMER_APP_EOST					(0x0004)
+#define U300_TIMER_APP_EOST_TIMER_ENABLE			(0x00000000)
+/* Disable OS Timer 32bit (-/W) */
+#define U300_TIMER_APP_DOST					(0x0008)
+#define U300_TIMER_APP_DOST_TIMER_DISABLE			(0x00000000)
+/* OS Timer Mode Register 32bit (-/W) */
+#define U300_TIMER_APP_SOSTM					(0x000c)
+#define U300_TIMER_APP_SOSTM_MODE_CONTINUOUS			(0x00000000)
+#define U300_TIMER_APP_SOSTM_MODE_ONE_SHOT			(0x00000001)
+/* OS Timer Status Register 32bit (R/-) */
+#define U300_TIMER_APP_OSTS					(0x0010)
+#define U300_TIMER_APP_OSTS_TIMER_STATE_MASK			(0x0000000F)
+#define U300_TIMER_APP_OSTS_TIMER_STATE_IDLE			(0x00000001)
+#define U300_TIMER_APP_OSTS_TIMER_STATE_ACTIVE			(0x00000002)
+#define U300_TIMER_APP_OSTS_ENABLE_IND				(0x00000010)
+#define U300_TIMER_APP_OSTS_MODE_MASK				(0x00000020)
+#define U300_TIMER_APP_OSTS_MODE_CONTINUOUS			(0x00000000)
+#define U300_TIMER_APP_OSTS_MODE_ONE_SHOT			(0x00000020)
+#define U300_TIMER_APP_OSTS_IRQ_ENABLED_IND			(0x00000040)
+#define U300_TIMER_APP_OSTS_IRQ_PENDING_IND			(0x00000080)
+/* OS Timer Current Count Register 32bit (R/-) */
+#define U300_TIMER_APP_OSTCC					(0x0014)
+/* OS Timer Terminal Count Register 32bit (R/W) */
+#define U300_TIMER_APP_OSTTC					(0x0018)
+/* OS Timer Interrupt Enable Register 32bit (-/W) */
+#define U300_TIMER_APP_OSTIE					(0x001c)
+#define U300_TIMER_APP_OSTIE_IRQ_DISABLE			(0x00000000)
+#define U300_TIMER_APP_OSTIE_IRQ_ENABLE				(0x00000001)
+/* OS Timer Interrupt Acknowledge Register 32bit (-/W) */
+#define U300_TIMER_APP_OSTIA					(0x0020)
+#define U300_TIMER_APP_OSTIA_IRQ_ACK				(0x00000080)
+
+/* Reset DD Timer 32bit (-/W) */
+#define U300_TIMER_APP_RDDT					(0x0040)
+#define U300_TIMER_APP_RDDT_TIMER_RESET				(0x00000000)
+/* Enable DD Timer 32bit (-/W) */
+#define U300_TIMER_APP_EDDT					(0x0044)
+#define U300_TIMER_APP_EDDT_TIMER_ENABLE			(0x00000000)
+/* Disable DD Timer 32bit (-/W) */
+#define U300_TIMER_APP_DDDT					(0x0048)
+#define U300_TIMER_APP_DDDT_TIMER_DISABLE			(0x00000000)
+/* DD Timer Mode Register 32bit (-/W) */
+#define U300_TIMER_APP_SDDTM					(0x004c)
+#define U300_TIMER_APP_SDDTM_MODE_CONTINUOUS			(0x00000000)
+#define U300_TIMER_APP_SDDTM_MODE_ONE_SHOT			(0x00000001)
+/* DD Timer Status Register 32bit (R/-) */
+#define U300_TIMER_APP_DDTS					(0x0050)
+#define U300_TIMER_APP_DDTS_TIMER_STATE_MASK			(0x0000000F)
+#define U300_TIMER_APP_DDTS_TIMER_STATE_IDLE			(0x00000001)
+#define U300_TIMER_APP_DDTS_TIMER_STATE_ACTIVE			(0x00000002)
+#define U300_TIMER_APP_DDTS_ENABLE_IND				(0x00000010)
+#define U300_TIMER_APP_DDTS_MODE_MASK				(0x00000020)
+#define U300_TIMER_APP_DDTS_MODE_CONTINUOUS			(0x00000000)
+#define U300_TIMER_APP_DDTS_MODE_ONE_SHOT			(0x00000020)
+#define U300_TIMER_APP_DDTS_IRQ_ENABLED_IND			(0x00000040)
+#define U300_TIMER_APP_DDTS_IRQ_PENDING_IND			(0x00000080)
+/* DD Timer Current Count Register 32bit (R/-) */
+#define U300_TIMER_APP_DDTCC					(0x0054)
+/* DD Timer Terminal Count Register 32bit (R/W) */
+#define U300_TIMER_APP_DDTTC					(0x0058)
+/* DD Timer Interrupt Enable Register 32bit (-/W) */
+#define U300_TIMER_APP_DDTIE					(0x005c)
+#define U300_TIMER_APP_DDTIE_IRQ_DISABLE			(0x00000000)
+#define U300_TIMER_APP_DDTIE_IRQ_ENABLE				(0x00000001)
+/* DD Timer Interrupt Acknowledge Register 32bit (-/W) */
+#define U300_TIMER_APP_DDTIA					(0x0060)
+#define U300_TIMER_APP_DDTIA_IRQ_ACK				(0x00000080)
+
+/* Reset GP1 Timer 32bit (-/W) */
+#define U300_TIMER_APP_RGPT1					(0x0080)
+#define U300_TIMER_APP_RGPT1_TIMER_RESET			(0x00000000)
+/* Enable GP1 Timer 32bit (-/W) */
+#define U300_TIMER_APP_EGPT1					(0x0084)
+#define U300_TIMER_APP_EGPT1_TIMER_ENABLE			(0x00000000)
+/* Disable GP1 Timer 32bit (-/W) */
+#define U300_TIMER_APP_DGPT1					(0x0088)
+#define U300_TIMER_APP_DGPT1_TIMER_DISABLE			(0x00000000)
+/* GP1 Timer Mode Register 32bit (-/W) */
+#define U300_TIMER_APP_SGPT1M					(0x008c)
+#define U300_TIMER_APP_SGPT1M_MODE_CONTINUOUS			(0x00000000)
+#define U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT			(0x00000001)
+/* GP1 Timer Status Register 32bit (R/-) */
+#define U300_TIMER_APP_GPT1S					(0x0090)
+#define U300_TIMER_APP_GPT1S_TIMER_STATE_MASK			(0x0000000F)
+#define U300_TIMER_APP_GPT1S_TIMER_STATE_IDLE			(0x00000001)
+#define U300_TIMER_APP_GPT1S_TIMER_STATE_ACTIVE			(0x00000002)
+#define U300_TIMER_APP_GPT1S_ENABLE_IND				(0x00000010)
+#define U300_TIMER_APP_GPT1S_MODE_MASK				(0x00000020)
+#define U300_TIMER_APP_GPT1S_MODE_CONTINUOUS			(0x00000000)
+#define U300_TIMER_APP_GPT1S_MODE_ONE_SHOT			(0x00000020)
+#define U300_TIMER_APP_GPT1S_IRQ_ENABLED_IND			(0x00000040)
+#define U300_TIMER_APP_GPT1S_IRQ_PENDING_IND			(0x00000080)
+/* GP1 Timer Current Count Register 32bit (R/-) */
+#define U300_TIMER_APP_GPT1CC					(0x0094)
+/* GP1 Timer Terminal Count Register 32bit (R/W) */
+#define U300_TIMER_APP_GPT1TC					(0x0098)
+/* GP1 Timer Interrupt Enable Register 32bit (-/W) */
+#define U300_TIMER_APP_GPT1IE					(0x009c)
+#define U300_TIMER_APP_GPT1IE_IRQ_DISABLE			(0x00000000)
+#define U300_TIMER_APP_GPT1IE_IRQ_ENABLE			(0x00000001)
+/* GP1 Timer Interrupt Acknowledge Register 32bit (-/W) */
+#define U300_TIMER_APP_GPT1IA					(0x00a0)
+#define U300_TIMER_APP_GPT1IA_IRQ_ACK				(0x00000080)
+
+/* Reset GP2 Timer 32bit (-/W) */
+#define U300_TIMER_APP_RGPT2					(0x00c0)
+#define U300_TIMER_APP_RGPT2_TIMER_RESET			(0x00000000)
+/* Enable GP2 Timer 32bit (-/W) */
+#define U300_TIMER_APP_EGPT2					(0x00c4)
+#define U300_TIMER_APP_EGPT2_TIMER_ENABLE			(0x00000000)
+/* Disable GP2 Timer 32bit (-/W) */
+#define U300_TIMER_APP_DGPT2					(0x00c8)
+#define U300_TIMER_APP_DGPT2_TIMER_DISABLE			(0x00000000)
+/* GP2 Timer Mode Register 32bit (-/W) */
+#define U300_TIMER_APP_SGPT2M					(0x00cc)
+#define U300_TIMER_APP_SGPT2M_MODE_CONTINUOUS			(0x00000000)
+#define U300_TIMER_APP_SGPT2M_MODE_ONE_SHOT			(0x00000001)
+/* GP2 Timer Status Register 32bit (R/-) */
+#define U300_TIMER_APP_GPT2S					(0x00d0)
+#define U300_TIMER_APP_GPT2S_TIMER_STATE_MASK			(0x0000000F)
+#define U300_TIMER_APP_GPT2S_TIMER_STATE_IDLE			(0x00000001)
+#define U300_TIMER_APP_GPT2S_TIMER_STATE_ACTIVE			(0x00000002)
+#define U300_TIMER_APP_GPT2S_ENABLE_IND				(0x00000010)
+#define U300_TIMER_APP_GPT2S_MODE_MASK				(0x00000020)
+#define U300_TIMER_APP_GPT2S_MODE_CONTINUOUS			(0x00000000)
+#define U300_TIMER_APP_GPT2S_MODE_ONE_SHOT			(0x00000020)
+#define U300_TIMER_APP_GPT2S_IRQ_ENABLED_IND			(0x00000040)
+#define U300_TIMER_APP_GPT2S_IRQ_PENDING_IND			(0x00000080)
+/* GP2 Timer Current Count Register 32bit (R/-) */
+#define U300_TIMER_APP_GPT2CC					(0x00d4)
+/* GP2 Timer Terminal Count Register 32bit (R/W) */
+#define U300_TIMER_APP_GPT2TC					(0x00d8)
+/* GP2 Timer Interrupt Enable Register 32bit (-/W) */
+#define U300_TIMER_APP_GPT2IE					(0x00dc)
+#define U300_TIMER_APP_GPT2IE_IRQ_DISABLE			(0x00000000)
+#define U300_TIMER_APP_GPT2IE_IRQ_ENABLE			(0x00000001)
+/* GP2 Timer Interrupt Acknowledge Register 32bit (-/W) */
+#define U300_TIMER_APP_GPT2IA					(0x00e0)
+#define U300_TIMER_APP_GPT2IA_IRQ_ACK				(0x00000080)
+
+/* Clock request control register - all four timers */
+#define U300_TIMER_APP_CRC					(0x100)
+#define U300_TIMER_APP_CRC_CLOCK_REQUEST_ENABLE			(0x00000001)
+
+static void __iomem *u300_timer_base;
+
+struct u300_clockevent_data {
+	struct clock_event_device cevd;
+	unsigned ticks_per_jiffy;
+};
+
+static int u300_shutdown(struct clock_event_device *evt)
+{
+	/* Disable interrupts on GP1 */
+	writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
+	       u300_timer_base + U300_TIMER_APP_GPT1IE);
+	/* Disable GP1 */
+	writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
+	       u300_timer_base + U300_TIMER_APP_DGPT1);
+	return 0;
+}
+
+/*
+ * If we have oneshot timer active, the oneshot scheduling function
+ * u300_set_next_event() is called immediately after.
+ */
+static int u300_set_oneshot(struct clock_event_device *evt)
+{
+	/* Just return; here? */
+	/*
+	 * The actual event will be programmed by the next event hook,
+	 * so we just set a dummy value somewhere at the end of the
+	 * universe here.
+	 */
+	/* Disable interrupts on GPT1 */
+	writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
+	       u300_timer_base + U300_TIMER_APP_GPT1IE);
+	/* Disable GP1 while we're reprogramming it. */
+	writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
+	       u300_timer_base + U300_TIMER_APP_DGPT1);
+	/*
+	 * Expire far in the future, u300_set_next_event() will be
+	 * called soon...
+	 */
+	writel(0xFFFFFFFF, u300_timer_base + U300_TIMER_APP_GPT1TC);
+	/* We run one shot per tick here! */
+	writel(U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT,
+	       u300_timer_base + U300_TIMER_APP_SGPT1M);
+	/* Enable interrupts for this timer */
+	writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE,
+	       u300_timer_base + U300_TIMER_APP_GPT1IE);
+	/* Enable timer */
+	writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE,
+	       u300_timer_base + U300_TIMER_APP_EGPT1);
+	return 0;
+}
+
+static int u300_set_periodic(struct clock_event_device *evt)
+{
+	struct u300_clockevent_data *cevdata =
+		container_of(evt, struct u300_clockevent_data, cevd);
+
+	/* Disable interrupts on GPT1 */
+	writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
+	       u300_timer_base + U300_TIMER_APP_GPT1IE);
+	/* Disable GP1 while we're reprogramming it. */
+	writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
+	       u300_timer_base + U300_TIMER_APP_DGPT1);
+	/*
+	 * Set the periodic mode to a certain number of ticks per
+	 * jiffy.
+	 */
+	writel(cevdata->ticks_per_jiffy,
+	       u300_timer_base + U300_TIMER_APP_GPT1TC);
+	/*
+	 * Set continuous mode, so the timer keeps triggering
+	 * interrupts.
+	 */
+	writel(U300_TIMER_APP_SGPT1M_MODE_CONTINUOUS,
+	       u300_timer_base + U300_TIMER_APP_SGPT1M);
+	/* Enable timer interrupts */
+	writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE,
+	       u300_timer_base + U300_TIMER_APP_GPT1IE);
+	/* Then enable the OS timer again */
+	writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE,
+	       u300_timer_base + U300_TIMER_APP_EGPT1);
+	return 0;
+}
+
+/*
+ * The app timer in one shot mode obviously has to be reprogrammed
+ * in EXACTLY this sequence to work properly. Do NOT try to e.g. replace
+ * the interrupt disable + timer disable commands with a reset command,
+ * it will fail miserably. Apparently (and I found this the hard way)
+ * the timer is very sensitive to the instruction order, though you don't
+ * get that impression from the data sheet.
+ */
+static int u300_set_next_event(unsigned long cycles,
+			       struct clock_event_device *evt)
+
+{
+	/* Disable interrupts on GPT1 */
+	writel(U300_TIMER_APP_GPT1IE_IRQ_DISABLE,
+	       u300_timer_base + U300_TIMER_APP_GPT1IE);
+	/* Disable GP1 while we're reprogramming it. */
+	writel(U300_TIMER_APP_DGPT1_TIMER_DISABLE,
+	       u300_timer_base + U300_TIMER_APP_DGPT1);
+	/* Reset the General Purpose timer 1. */
+	writel(U300_TIMER_APP_RGPT1_TIMER_RESET,
+	       u300_timer_base + U300_TIMER_APP_RGPT1);
+	/* IRQ in n * cycles */
+	writel(cycles, u300_timer_base + U300_TIMER_APP_GPT1TC);
+	/*
+	 * We run one shot per tick here! (This is necessary to reconfigure,
+	 * the timer will tilt if you don't!)
+	 */
+	writel(U300_TIMER_APP_SGPT1M_MODE_ONE_SHOT,
+	       u300_timer_base + U300_TIMER_APP_SGPT1M);
+	/* Enable timer interrupts */
+	writel(U300_TIMER_APP_GPT1IE_IRQ_ENABLE,
+	       u300_timer_base + U300_TIMER_APP_GPT1IE);
+	/* Then enable the OS timer again */
+	writel(U300_TIMER_APP_EGPT1_TIMER_ENABLE,
+	       u300_timer_base + U300_TIMER_APP_EGPT1);
+	return 0;
+}
+
+static struct u300_clockevent_data u300_clockevent_data = {
+	/* Use general purpose timer 1 as clock event */
+	.cevd = {
+		.name			= "GPT1",
+		/* Reasonably fast and accurate clock event */
+		.rating			= 300,
+		.features		= CLOCK_EVT_FEAT_PERIODIC |
+					  CLOCK_EVT_FEAT_ONESHOT,
+		.set_next_event		= u300_set_next_event,
+		.set_state_shutdown	= u300_shutdown,
+		.set_state_periodic	= u300_set_periodic,
+		.set_state_oneshot	= u300_set_oneshot,
+	},
+};
+
+/* Clock event timer interrupt handler */
+static irqreturn_t u300_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = &u300_clockevent_data.cevd;
+	/* ACK/Clear timer IRQ for the APP GPT1 Timer */
+
+	writel(U300_TIMER_APP_GPT1IA_IRQ_ACK,
+		u300_timer_base + U300_TIMER_APP_GPT1IA);
+	evt->event_handler(evt);
+	return IRQ_HANDLED;
+}
+
+static struct irqaction u300_timer_irq = {
+	.name		= "U300 Timer Tick",
+	.flags		= IRQF_TIMER | IRQF_IRQPOLL,
+	.handler	= u300_timer_interrupt,
+};
+
+/*
+ * Override the global weak sched_clock symbol with this
+ * local implementation which uses the clocksource to get some
+ * better resolution when scheduling the kernel. We accept that
+ * this wraps around for now, since it is just a relative time
+ * stamp. (Inspired by OMAP implementation.)
+ */
+
+static u64 notrace u300_read_sched_clock(void)
+{
+	return readl(u300_timer_base + U300_TIMER_APP_GPT2CC);
+}
+
+static unsigned long u300_read_current_timer(void)
+{
+	return readl(u300_timer_base + U300_TIMER_APP_GPT2CC);
+}
+
+static struct delay_timer u300_delay_timer;
+
+/*
+ * This sets up the system timers, clock source and clock event.
+ */
+static int __init u300_timer_init_of(struct device_node *np)
+{
+	unsigned int irq;
+	struct clk *clk;
+	unsigned long rate;
+	int ret;
+
+	u300_timer_base = of_iomap(np, 0);
+	if (!u300_timer_base) {
+		pr_err("could not ioremap system timer\n");
+		return -ENXIO;
+	}
+
+	/* Get the IRQ for the GP1 timer */
+	irq = irq_of_parse_and_map(np, 2);
+	if (!irq) {
+		pr_err("no IRQ for system timer\n");
+		return -EINVAL;
+	}
+
+	pr_info("U300 GP1 timer @ base: %p, IRQ: %u\n", u300_timer_base, irq);
+
+	/* Clock the interrupt controller */
+	clk = of_clk_get(np, 0);
+	if (IS_ERR(clk))
+		return PTR_ERR(clk);
+
+	ret = clk_prepare_enable(clk);
+	if (ret)
+		return ret;
+
+	rate = clk_get_rate(clk);
+
+	u300_clockevent_data.ticks_per_jiffy = DIV_ROUND_CLOSEST(rate, HZ);
+
+	sched_clock_register(u300_read_sched_clock, 32, rate);
+
+	u300_delay_timer.read_current_timer = &u300_read_current_timer;
+	u300_delay_timer.freq = rate;
+	register_current_timer_delay(&u300_delay_timer);
+
+	/*
+	 * Disable the "OS" and "DD" timers - these are designed for Symbian!
+	 * Example usage in cnh1601578 cpu subsystem pd_timer_app.c
+	 */
+	writel(U300_TIMER_APP_CRC_CLOCK_REQUEST_ENABLE,
+		u300_timer_base + U300_TIMER_APP_CRC);
+	writel(U300_TIMER_APP_ROST_TIMER_RESET,
+		u300_timer_base + U300_TIMER_APP_ROST);
+	writel(U300_TIMER_APP_DOST_TIMER_DISABLE,
+		u300_timer_base + U300_TIMER_APP_DOST);
+	writel(U300_TIMER_APP_RDDT_TIMER_RESET,
+		u300_timer_base + U300_TIMER_APP_RDDT);
+	writel(U300_TIMER_APP_DDDT_TIMER_DISABLE,
+		u300_timer_base + U300_TIMER_APP_DDDT);
+
+	/* Reset the General Purpose timer 1. */
+	writel(U300_TIMER_APP_RGPT1_TIMER_RESET,
+		u300_timer_base + U300_TIMER_APP_RGPT1);
+
+	/* Set up the IRQ handler */
+	ret = setup_irq(irq, &u300_timer_irq);
+	if (ret)
+		return ret;
+
+	/* Reset the General Purpose timer 2 */
+	writel(U300_TIMER_APP_RGPT2_TIMER_RESET,
+		u300_timer_base + U300_TIMER_APP_RGPT2);
+	/* Set this timer to run around forever */
+	writel(0xFFFFFFFFU, u300_timer_base + U300_TIMER_APP_GPT2TC);
+	/* Set continuous mode so it wraps around */
+	writel(U300_TIMER_APP_SGPT2M_MODE_CONTINUOUS,
+	       u300_timer_base + U300_TIMER_APP_SGPT2M);
+	/* Disable timer interrupts */
+	writel(U300_TIMER_APP_GPT2IE_IRQ_DISABLE,
+		u300_timer_base + U300_TIMER_APP_GPT2IE);
+	/* Then enable the GP2 timer to use as a free running us counter */
+	writel(U300_TIMER_APP_EGPT2_TIMER_ENABLE,
+		u300_timer_base + U300_TIMER_APP_EGPT2);
+
+	/* Use general purpose timer 2 as clock source */
+	ret = clocksource_mmio_init(u300_timer_base + U300_TIMER_APP_GPT2CC,
+				    "GPT2", rate, 300, 32, clocksource_mmio_readl_up);
+	if (ret) {
+		pr_err("timer: failed to initialize U300 clock source\n");
+		return ret;
+	}
+
+	/* Configure and register the clockevent */
+	clockevents_config_and_register(&u300_clockevent_data.cevd, rate,
+					1, 0xffffffff);
+
+	/*
+	 * TODO: init and register the rest of the timers too, they can be
+	 * used by hrtimers!
+	 */
+	return 0;
+}
+
+TIMER_OF_DECLARE(u300_timer, "stericsson,u300-apptimer",
+		       u300_timer_init_of);

drivers/clocksource/versatile.c

@@ -0,0 +1,44 @@
+/*
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * Copyright (C) 2014 ARM Limited
+ */
+
+#include <linux/clocksource.h>
+#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/sched_clock.h>
+
+#define SYS_24MHZ 0x05c
+
+static void __iomem *versatile_sys_24mhz;
+
+static u64 notrace versatile_sys_24mhz_read(void)
+{
+	return readl(versatile_sys_24mhz);
+}
+
+static int __init versatile_sched_clock_init(struct device_node *node)
+{
+	void __iomem *base = of_iomap(node, 0);
+
+	if (!base)
+		return -ENXIO;
+
+	versatile_sys_24mhz = base + SYS_24MHZ;
+
+	sched_clock_register(versatile_sys_24mhz_read, 32, 24000000);
+
+	return 0;
+}
+TIMER_OF_DECLARE(vexpress, "arm,vexpress-sysreg",
+		       versatile_sched_clock_init);
+TIMER_OF_DECLARE(versatile, "arm,versatile-sysreg",
+		       versatile_sched_clock_init);

drivers/clocksource/vf_pit_timer.c

@@ -0,0 +1,204 @@
+/*
+ * Copyright 2012-2013 Freescale Semiconductor, Inc.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/clockchips.h>
+#include <linux/clk.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/sched_clock.h>
+
+/*
+ * Each pit takes 0x10 Bytes register space
+ */
+#define PITMCR		0x00
+#define PIT0_OFFSET	0x100
+#define PITn_OFFSET(n)	(PIT0_OFFSET + 0x10 * (n))
+#define PITLDVAL	0x00
+#define PITCVAL		0x04
+#define PITTCTRL	0x08
+#define PITTFLG		0x0c
+
+#define PITMCR_MDIS	(0x1 << 1)
+
+#define PITTCTRL_TEN	(0x1 << 0)
+#define PITTCTRL_TIE	(0x1 << 1)
+#define PITCTRL_CHN	(0x1 << 2)
+
+#define PITTFLG_TIF	0x1
+
+static void __iomem *clksrc_base;
+static void __iomem *clkevt_base;
+static unsigned long cycle_per_jiffy;
+
+static inline void pit_timer_enable(void)
+{
+	__raw_writel(PITTCTRL_TEN | PITTCTRL_TIE, clkevt_base + PITTCTRL);
+}
+
+static inline void pit_timer_disable(void)
+{
+	__raw_writel(0, clkevt_base + PITTCTRL);
+}
+
+static inline void pit_irq_acknowledge(void)
+{
+	__raw_writel(PITTFLG_TIF, clkevt_base + PITTFLG);
+}
+
+static u64 notrace pit_read_sched_clock(void)
+{
+	return ~__raw_readl(clksrc_base + PITCVAL);
+}
+
+static int __init pit_clocksource_init(unsigned long rate)
+{
+	/* set the max load value and start the clock source counter */
+	__raw_writel(0, clksrc_base + PITTCTRL);
+	__raw_writel(~0UL, clksrc_base + PITLDVAL);
+	__raw_writel(PITTCTRL_TEN, clksrc_base + PITTCTRL);
+
+	sched_clock_register(pit_read_sched_clock, 32, rate);
+	return clocksource_mmio_init(clksrc_base + PITCVAL, "vf-pit", rate,
+			300, 32, clocksource_mmio_readl_down);
+}
+
+static int pit_set_next_event(unsigned long delta,
+				struct clock_event_device *unused)
+{
+	/*
+	 * set a new value to PITLDVAL register will not restart the timer,
+	 * to abort the current cycle and start a timer period with the new
+	 * value, the timer must be disabled and enabled again.
+	 * and the PITLAVAL should be set to delta minus one according to pit
+	 * hardware requirement.
+	 */
+	pit_timer_disable();
+	__raw_writel(delta - 1, clkevt_base + PITLDVAL);
+	pit_timer_enable();
+
+	return 0;
+}
+
+static int pit_shutdown(struct clock_event_device *evt)
+{
+	pit_timer_disable();
+	return 0;
+}
+
+static int pit_set_periodic(struct clock_event_device *evt)
+{
+	pit_set_next_event(cycle_per_jiffy, evt);
+	return 0;
+}
+
+static irqreturn_t pit_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+
+	pit_irq_acknowledge();
+
+	/*
+	 * pit hardware doesn't support oneshot, it will generate an interrupt
+	 * and reload the counter value from PITLDVAL when PITCVAL reach zero,
+	 * and start the counter again. So software need to disable the timer
+	 * to stop the counter loop in ONESHOT mode.
+	 */
+	if (likely(clockevent_state_oneshot(evt)))
+		pit_timer_disable();
+
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static struct clock_event_device clockevent_pit = {
+	.name		= "VF pit timer",
+	.features	= CLOCK_EVT_FEAT_PERIODIC | CLOCK_EVT_FEAT_ONESHOT,
+	.set_state_shutdown = pit_shutdown,
+	.set_state_periodic = pit_set_periodic,
+	.set_next_event	= pit_set_next_event,
+	.rating		= 300,
+};
+
+static struct irqaction pit_timer_irq = {
+	.name		= "VF pit timer",
+	.flags		= IRQF_TIMER | IRQF_IRQPOLL,
+	.handler	= pit_timer_interrupt,
+	.dev_id		= &clockevent_pit,
+};
+
+static int __init pit_clockevent_init(unsigned long rate, int irq)
+{
+	__raw_writel(0, clkevt_base + PITTCTRL);
+	__raw_writel(PITTFLG_TIF, clkevt_base + PITTFLG);
+
+	BUG_ON(setup_irq(irq, &pit_timer_irq));
+
+	clockevent_pit.cpumask = cpumask_of(0);
+	clockevent_pit.irq = irq;
+	/*
+	 * The value for the LDVAL register trigger is calculated as:
+	 * LDVAL trigger = (period / clock period) - 1
+	 * The pit is a 32-bit down count timer, when the conter value
+	 * reaches 0, it will generate an interrupt, thus the minimal
+	 * LDVAL trigger value is 1. And then the min_delta is
+	 * minimal LDVAL trigger value + 1, and the max_delta is full 32-bit.
+	 */
+	clockevents_config_and_register(&clockevent_pit, rate, 2, 0xffffffff);
+
+	return 0;
+}
+
+static int __init pit_timer_init(struct device_node *np)
+{
+	struct clk *pit_clk;
+	void __iomem *timer_base;
+	unsigned long clk_rate;
+	int irq, ret;
+
+	timer_base = of_iomap(np, 0);
+	if (!timer_base) {
+		pr_err("Failed to iomap\n");
+		return -ENXIO;
+	}
+
+	/*
+	 * PIT0 and PIT1 can be chained to build a 64-bit timer,
+	 * so choose PIT2 as clocksource, PIT3 as clockevent device,
+	 * and leave PIT0 and PIT1 unused for anyone else who needs them.
+	 */
+	clksrc_base = timer_base + PITn_OFFSET(2);
+	clkevt_base = timer_base + PITn_OFFSET(3);
+
+	irq = irq_of_parse_and_map(np, 0);
+	if (irq <= 0)
+		return -EINVAL;
+
+	pit_clk = of_clk_get(np, 0);
+	if (IS_ERR(pit_clk))
+		return PTR_ERR(pit_clk);
+
+	ret = clk_prepare_enable(pit_clk);
+	if (ret)
+		return ret;
+
+	clk_rate = clk_get_rate(pit_clk);
+	cycle_per_jiffy = clk_rate / (HZ);
+
+	/* enable the pit module */
+	__raw_writel(~PITMCR_MDIS, timer_base + PITMCR);
+
+	ret = pit_clocksource_init(clk_rate);
+	if (ret)
+		return ret;
+
+	return pit_clockevent_init(clk_rate, irq);
+}
+TIMER_OF_DECLARE(vf610, "fsl,vf610-pit", pit_timer_init);

drivers/clocksource/vt8500_timer.c

@@ -0,0 +1,168 @@
+/*
+ *  arch/arm/mach-vt8500/timer.c
+ *
+ *  Copyright (C) 2012 Tony Prisk <linux@prisktech.co.nz>
+ *  Copyright (C) 2010 Alexey Charkov <alchark@gmail.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/*
+ * This file is copied and modified from the original timer.c provided by
+ * Alexey Charkov. Minor changes have been made for Device Tree Support.
+ */
+
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
+#include <linux/clocksource.h>
+#include <linux/clockchips.h>
+#include <linux/delay.h>
+
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#define VT8500_TIMER_OFFSET	0x0100
+#define VT8500_TIMER_HZ		3000000
+#define TIMER_MATCH_VAL		0x0000
+#define TIMER_COUNT_VAL		0x0010
+#define TIMER_STATUS_VAL	0x0014
+#define TIMER_IER_VAL		0x001c		/* interrupt enable */
+#define TIMER_CTRL_VAL		0x0020
+#define TIMER_AS_VAL		0x0024		/* access status */
+#define TIMER_COUNT_R_ACTIVE	(1 << 5)	/* not ready for read */
+#define TIMER_COUNT_W_ACTIVE	(1 << 4)	/* not ready for write */
+#define TIMER_MATCH_W_ACTIVE	(1 << 0)	/* not ready for write */
+
+#define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
+
+#define MIN_OSCR_DELTA		16
+
+static void __iomem *regbase;
+
+static u64 vt8500_timer_read(struct clocksource *cs)
+{
+	int loops = msecs_to_loops(10);
+	writel(3, regbase + TIMER_CTRL_VAL);
+	while ((readl((regbase + TIMER_AS_VAL)) & TIMER_COUNT_R_ACTIVE)
+						&& --loops)
+		cpu_relax();
+	return readl(regbase + TIMER_COUNT_VAL);
+}
+
+static struct clocksource clocksource = {
+	.name           = "vt8500_timer",
+	.rating         = 200,
+	.read           = vt8500_timer_read,
+	.mask           = CLOCKSOURCE_MASK(32),
+	.flags          = CLOCK_SOURCE_IS_CONTINUOUS,
+};
+
+static int vt8500_timer_set_next_event(unsigned long cycles,
+				    struct clock_event_device *evt)
+{
+	int loops = msecs_to_loops(10);
+	u64 alarm = clocksource.read(&clocksource) + cycles;
+	while ((readl(regbase + TIMER_AS_VAL) & TIMER_MATCH_W_ACTIVE)
+						&& --loops)
+		cpu_relax();
+	writel((unsigned long)alarm, regbase + TIMER_MATCH_VAL);
+
+	if ((signed)(alarm - clocksource.read(&clocksource)) <= MIN_OSCR_DELTA)
+		return -ETIME;
+
+	writel(1, regbase + TIMER_IER_VAL);
+
+	return 0;
+}
+
+static int vt8500_shutdown(struct clock_event_device *evt)
+{
+	writel(readl(regbase + TIMER_CTRL_VAL) | 1, regbase + TIMER_CTRL_VAL);
+	writel(0, regbase + TIMER_IER_VAL);
+	return 0;
+}
+
+static struct clock_event_device clockevent = {
+	.name			= "vt8500_timer",
+	.features		= CLOCK_EVT_FEAT_ONESHOT,
+	.rating			= 200,
+	.set_next_event		= vt8500_timer_set_next_event,
+	.set_state_shutdown	= vt8500_shutdown,
+	.set_state_oneshot	= vt8500_shutdown,
+};
+
+static irqreturn_t vt8500_timer_interrupt(int irq, void *dev_id)
+{
+	struct clock_event_device *evt = dev_id;
+	writel(0xf, regbase + TIMER_STATUS_VAL);
+	evt->event_handler(evt);
+
+	return IRQ_HANDLED;
+}
+
+static struct irqaction irq = {
+	.name    = "vt8500_timer",
+	.flags   = IRQF_TIMER | IRQF_IRQPOLL,
+	.handler = vt8500_timer_interrupt,
+	.dev_id  = &clockevent,
+};
+
+static int __init vt8500_timer_init(struct device_node *np)
+{
+	int timer_irq, ret;
+
+	regbase = of_iomap(np, 0);
+	if (!regbase) {
+		pr_err("%s: Missing iobase description in Device Tree\n",
+								__func__);
+		return -ENXIO;
+	}
+
+	timer_irq = irq_of_parse_and_map(np, 0);
+	if (!timer_irq) {
+		pr_err("%s: Missing irq description in Device Tree\n",
+								__func__);
+		return -EINVAL;
+	}
+
+	writel(1, regbase + TIMER_CTRL_VAL);
+	writel(0xf, regbase + TIMER_STATUS_VAL);
+	writel(~0, regbase + TIMER_MATCH_VAL);
+
+	ret = clocksource_register_hz(&clocksource, VT8500_TIMER_HZ);
+	if (ret) {
+		pr_err("%s: vt8500_timer_init: clocksource_register failed for %s\n",
+		       __func__, clocksource.name);
+		return ret;
+	}
+
+	clockevent.cpumask = cpumask_of(0);
+
+	ret = setup_irq(timer_irq, &irq);
+	if (ret) {
+		pr_err("%s: setup_irq failed for %s\n", __func__,
+							clockevent.name);
+		return ret;
+	}
+
+	clockevents_config_and_register(&clockevent, VT8500_TIMER_HZ,
+					MIN_OSCR_DELTA * 2, 0xf0000000);
+
+	return 0;
+}
+
+TIMER_OF_DECLARE(vt8500, "via,vt8500-timer", vt8500_timer_init);

drivers/clocksource/zevio-timer.c

@@ -0,0 +1,218 @@
+/*
+ *  linux/drivers/clocksource/zevio-timer.c
+ *
+ *  Copyright (C) 2013 Daniel Tang <tangrs@tangrs.id.au>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <linux/io.h>
+#include <linux/irq.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/clk.h>
+#include <linux/clockchips.h>
+#include <linux/cpumask.h>
+#include <linux/interrupt.h>
+#include <linux/slab.h>
+
+#define IO_CURRENT_VAL	0x00
+#define IO_DIVIDER	0x04
+#define IO_CONTROL	0x08
+
+#define IO_TIMER1	0x00
+#define IO_TIMER2	0x0C
+
+#define IO_MATCH_BEGIN	0x18
+#define IO_MATCH(x)	(IO_MATCH_BEGIN + ((x) << 2))
+
+#define IO_INTR_STS	0x00
+#define IO_INTR_ACK	0x00
+#define IO_INTR_MSK	0x04
+
+#define CNTL_STOP_TIMER	(1 << 4)
+#define CNTL_RUN_TIMER	(0 << 4)
+
+#define CNTL_INC	(1 << 3)
+#define CNTL_DEC	(0 << 3)
+
+#define CNTL_TOZERO	0
+#define CNTL_MATCH(x)	((x) + 1)
+#define CNTL_FOREVER	7
+
+/* There are 6 match registers but we only use one. */
+#define TIMER_MATCH	0
+
+#define TIMER_INTR_MSK	(1 << (TIMER_MATCH))
+#define TIMER_INTR_ALL	0x3F
+
+struct zevio_timer {
+	void __iomem *base;
+	void __iomem *timer1, *timer2;
+	void __iomem *interrupt_regs;
+
+	struct clk *clk;
+	struct clock_event_device clkevt;
+	struct irqaction clkevt_irq;
+
+	char clocksource_name[64];
+	char clockevent_name[64];
+};
+
+static int zevio_timer_set_event(unsigned long delta,
+				 struct clock_event_device *dev)
+{
+	struct zevio_timer *timer = container_of(dev, struct zevio_timer,
+						 clkevt);
+
+	writel(delta, timer->timer1 + IO_CURRENT_VAL);
+	writel(CNTL_RUN_TIMER | CNTL_DEC | CNTL_MATCH(TIMER_MATCH),
+			timer->timer1 + IO_CONTROL);
+
+	return 0;
+}
+
+static int zevio_timer_shutdown(struct clock_event_device *dev)
+{
+	struct zevio_timer *timer = container_of(dev, struct zevio_timer,
+						 clkevt);
+
+	/* Disable timer interrupts */
+	writel(0, timer->interrupt_regs + IO_INTR_MSK);
+	writel(TIMER_INTR_ALL, timer->interrupt_regs + IO_INTR_ACK);
+	/* Stop timer */
+	writel(CNTL_STOP_TIMER, timer->timer1 + IO_CONTROL);
+	return 0;
+}
+
+static int zevio_timer_set_oneshot(struct clock_event_device *dev)
+{
+	struct zevio_timer *timer = container_of(dev, struct zevio_timer,
+						 clkevt);
+
+	/* Enable timer interrupts */
+	writel(TIMER_INTR_MSK, timer->interrupt_regs + IO_INTR_MSK);
+	writel(TIMER_INTR_ALL, timer->interrupt_regs + IO_INTR_ACK);
+	return 0;
+}
+
+static irqreturn_t zevio_timer_interrupt(int irq, void *dev_id)
+{
+	struct zevio_timer *timer = dev_id;
+	u32 intr;
+
+	intr = readl(timer->interrupt_regs + IO_INTR_ACK);
+	if (!(intr & TIMER_INTR_MSK))
+		return IRQ_NONE;
+
+	writel(TIMER_INTR_MSK, timer->interrupt_regs + IO_INTR_ACK);
+	writel(CNTL_STOP_TIMER, timer->timer1 + IO_CONTROL);
+
+	if (timer->clkevt.event_handler)
+		timer->clkevt.event_handler(&timer->clkevt);
+
+	return IRQ_HANDLED;
+}
+
+static int __init zevio_timer_add(struct device_node *node)
+{
+	struct zevio_timer *timer;
+	struct resource res;
+	int irqnr, ret;
+
+	timer = kzalloc(sizeof(*timer), GFP_KERNEL);
+	if (!timer)
+		return -ENOMEM;
+
+	timer->base = of_iomap(node, 0);
+	if (!timer->base) {
+		ret = -EINVAL;
+		goto error_free;
+	}
+	timer->timer1 = timer->base + IO_TIMER1;
+	timer->timer2 = timer->base + IO_TIMER2;
+
+	timer->clk = of_clk_get(node, 0);
+	if (IS_ERR(timer->clk)) {
+		ret = PTR_ERR(timer->clk);
+		pr_err("Timer clock not found! (error %d)\n", ret);
+		goto error_unmap;
+	}
+
+	timer->interrupt_regs = of_iomap(node, 1);
+	irqnr = irq_of_parse_and_map(node, 0);
+
+	of_address_to_resource(node, 0, &res);
+	scnprintf(timer->clocksource_name, sizeof(timer->clocksource_name),
+			"%llx.%s_clocksource",
+			(unsigned long long)res.start, node->name);
+
+	scnprintf(timer->clockevent_name, sizeof(timer->clockevent_name),
+			"%llx.%s_clockevent",
+			(unsigned long long)res.start, node->name);
+
+	if (timer->interrupt_regs && irqnr) {
+		timer->clkevt.name		= timer->clockevent_name;
+		timer->clkevt.set_next_event	= zevio_timer_set_event;
+		timer->clkevt.set_state_shutdown = zevio_timer_shutdown;
+		timer->clkevt.set_state_oneshot = zevio_timer_set_oneshot;
+		timer->clkevt.tick_resume	= zevio_timer_set_oneshot;
+		timer->clkevt.rating		= 200;
+		timer->clkevt.cpumask		= cpu_possible_mask;
+		timer->clkevt.features		= CLOCK_EVT_FEAT_ONESHOT;
+		timer->clkevt.irq		= irqnr;
+
+		writel(CNTL_STOP_TIMER, timer->timer1 + IO_CONTROL);
+		writel(0, timer->timer1 + IO_DIVIDER);
+
+		/* Start with timer interrupts disabled */
+		writel(0, timer->interrupt_regs + IO_INTR_MSK);
+		writel(TIMER_INTR_ALL, timer->interrupt_regs + IO_INTR_ACK);
+
+		/* Interrupt to occur when timer value matches 0 */
+		writel(0, timer->base + IO_MATCH(TIMER_MATCH));
+
+		timer->clkevt_irq.name		= timer->clockevent_name;
+		timer->clkevt_irq.handler	= zevio_timer_interrupt;
+		timer->clkevt_irq.dev_id	= timer;
+		timer->clkevt_irq.flags		= IRQF_TIMER | IRQF_IRQPOLL;
+
+		setup_irq(irqnr, &timer->clkevt_irq);
+
+		clockevents_config_and_register(&timer->clkevt,
+				clk_get_rate(timer->clk), 0x0001, 0xffff);
+		pr_info("Added %s as clockevent\n", timer->clockevent_name);
+	}
+
+	writel(CNTL_STOP_TIMER, timer->timer2 + IO_CONTROL);
+	writel(0, timer->timer2 + IO_CURRENT_VAL);
+	writel(0, timer->timer2 + IO_DIVIDER);
+	writel(CNTL_RUN_TIMER | CNTL_FOREVER | CNTL_INC,
+			timer->timer2 + IO_CONTROL);
+
+	clocksource_mmio_init(timer->timer2 + IO_CURRENT_VAL,
+			timer->clocksource_name,
+			clk_get_rate(timer->clk),
+			200, 16,
+			clocksource_mmio_readw_up);
+
+	pr_info("Added %s as clocksource\n", timer->clocksource_name);
+
+	return 0;
+error_unmap:
+	iounmap(timer->base);
+error_free:
+	kfree(timer);
+	return ret;
+}
+
+static int __init zevio_timer_init(struct device_node *node)
+{
+	return zevio_timer_add(node);
+}
+
+TIMER_OF_DECLARE(zevio_timer, "lsi,zevio-timer", zevio_timer_init);