unplugged-kernel/drivers/misc/mediatek/dramc/mt6853/mtk_dramc_wa.c

111 lines
2.7 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2019 MediaTek Inc.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/device.h>
#include <linux/platform_device.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/of_address.h>
#include <linux/printk.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/interrupt.h>
#include <memory/mediatek/dramc.h>
#include <linux/bug.h>
#include <mt-plat/sync_write.h>
#include "mtk_dramc_wa.h"
#define APXGPT_OF_COMPTIBLE_NAME "mediatek,apxgpt"
static struct mt_gpt_timers gpt_timers;
static irqreturn_t dramc_apxgpt3_irq_handler(int irq, void *dev_id)
{
/* pr_info("%s\n", __func__); */
/* 1. Stop and clear GPT */
mt_reg_sync_writel(GPT3_STOP_CLEAR, GPT3_CON);
/* 2. Clear pending irq */
mt_reg_sync_writel(GPT3_IRQ_BIT, GPT_IRQ_ACK);
/* 3. Configure GPT divider to 1 and using 32K clock source */
mt_reg_sync_writel(GPT3_RTC_CLK, GPT3_CLK);
/* 4. Calculate and Set compare value */
mt_reg_sync_writel(32768*1000/1000, GPT3_CMP_L);
/* 5. Set GTP3 SPE */
mt_reg_sync_writel(GPT3_IRQ_SPE, GPT3_SPE);
/* 6. Enabel IRQ En */
mt_reg_sync_writel(GPT3_IRQ_BIT, GPT_IRQ_EN);
return IRQ_HANDLED;
}
static int dramc_apxgpt3_init(void)
{
struct device_node *node;
int ret = 0;
const struct of_device_id apxgpt_of_match[] = {
{ .compatible = APXGPT_OF_COMPTIBLE_NAME, },
};
node = of_find_compatible_node(NULL, NULL,
apxgpt_of_match[0].compatible);
if (!node) {
pr_info("%s: node not found\n", __func__);
return -1;
}
/* Setup IRQ numbers */
gpt_timers.tmr_irq = irq_of_parse_and_map(node, 0);
/* Setup IO addresses */
gpt_timers.tmr_regs = of_iomap(node, 0);
pr_info("%s: base=0x%lx, irq=%d\n", __func__,
(unsigned long)gpt_timers.tmr_regs, gpt_timers.tmr_irq);
/* 1. Stop and clear GPT */
mt_reg_sync_writel(GPT3_STOP_CLEAR, GPT3_CON);
/* 2. Clear pending irq */
mt_reg_sync_writel(GPT3_IRQ_BIT, GPT_IRQ_ACK);
/* 3. Configure GPT divider to 1 and using 32K clock source */
mt_reg_sync_writel(GPT3_RTC_CLK, GPT3_CLK);
/* 4. Calculate and Set compare value */
mt_reg_sync_writel(32768*1000/1000, GPT3_CMP_L);
/* 5. Set GPT3 SPE */
mt_reg_sync_writel(GPT3_IRQ_SPE, GPT3_SPE);
/* 6. Enabel IRQ En */
mt_reg_sync_writel(GPT3_IRQ_BIT, GPT_IRQ_EN);
ret = request_irq(gpt_timers.tmr_irq, dramc_apxgpt3_irq_handler,
IRQF_TIMER | IRQF_IRQPOLL | IRQF_PERCPU,
"dramc_apxgpt3", NULL);
if (ret) {
pr_info("%s: apxgpt3 request irq Failed ret =%d\n",
__func__, ret);
return ret;
}
/* pr_info("%s: enable apxgpt3 one-shot", __func__); */
/* 7. Start GPT one-shot */
/* mt_reg_sync_writel(GPT3_ONE_SHOT_EN, GPT3_CON); */
return 0;
}
late_initcall(dramc_apxgpt3_init);
MODULE_DESCRIPTION("MediaTek DRAMC WA Driver v0.1");