272 строки
6.2 KiB
C
272 строки
6.2 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* Mediatek Watchdog Driver
|
|
*
|
|
* Copyright (C) 2014 Matthias Brugger
|
|
*
|
|
* Matthias Brugger <matthias.bgg@gmail.com>
|
|
*
|
|
* Based on sunxi_wdt.c
|
|
*/
|
|
|
|
#include <linux/err.h>
|
|
#include <linux/init.h>
|
|
#include <linux/io.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/moduleparam.h>
|
|
#include <linux/of.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/types.h>
|
|
#include <linux/watchdog.h>
|
|
#include <linux/delay.h>
|
|
|
|
#define WDT_MAX_TIMEOUT 31
|
|
#define WDT_MIN_TIMEOUT 1
|
|
#define WDT_LENGTH_TIMEOUT(n) ((n) << 5)
|
|
|
|
#define WDT_LENGTH 0x04
|
|
#define WDT_LENGTH_KEY 0x8
|
|
|
|
#define WDT_RST 0x08
|
|
#define WDT_RST_RELOAD 0x1971
|
|
|
|
#define WDT_MODE 0x00
|
|
#define WDT_MODE_EN (1 << 0)
|
|
#define WDT_MODE_EXT_POL_LOW (0 << 1)
|
|
#define WDT_MODE_EXT_POL_HIGH (1 << 1)
|
|
#define WDT_MODE_EXRST_EN (1 << 2)
|
|
#define WDT_MODE_IRQ_EN (1 << 3)
|
|
#define WDT_MODE_AUTO_START (1 << 4)
|
|
#define WDT_MODE_DUAL_EN (1 << 6)
|
|
#define WDT_MODE_KEY 0x22000000
|
|
|
|
#define WDT_SWRST 0x14
|
|
#define WDT_SWRST_KEY 0x1209
|
|
|
|
#define DRV_NAME "mtk-wdt"
|
|
#define DRV_VERSION "1.0"
|
|
|
|
static bool nowayout = WATCHDOG_NOWAYOUT;
|
|
static unsigned int timeout;
|
|
|
|
struct mtk_wdt_dev {
|
|
struct watchdog_device wdt_dev;
|
|
void __iomem *wdt_base;
|
|
};
|
|
|
|
static int mtk_wdt_restart(struct watchdog_device *wdt_dev,
|
|
unsigned long action, void *data)
|
|
{
|
|
struct mtk_wdt_dev *mtk_wdt = watchdog_get_drvdata(wdt_dev);
|
|
void __iomem *wdt_base;
|
|
|
|
wdt_base = mtk_wdt->wdt_base;
|
|
|
|
while (1) {
|
|
writel(WDT_SWRST_KEY, wdt_base + WDT_SWRST);
|
|
mdelay(5);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int mtk_wdt_ping(struct watchdog_device *wdt_dev)
|
|
{
|
|
struct mtk_wdt_dev *mtk_wdt = watchdog_get_drvdata(wdt_dev);
|
|
void __iomem *wdt_base = mtk_wdt->wdt_base;
|
|
|
|
iowrite32(WDT_RST_RELOAD, wdt_base + WDT_RST);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int mtk_wdt_set_timeout(struct watchdog_device *wdt_dev,
|
|
unsigned int timeout)
|
|
{
|
|
struct mtk_wdt_dev *mtk_wdt = watchdog_get_drvdata(wdt_dev);
|
|
void __iomem *wdt_base = mtk_wdt->wdt_base;
|
|
u32 reg;
|
|
|
|
wdt_dev->timeout = timeout;
|
|
|
|
/*
|
|
* One bit is the value of 512 ticks
|
|
* The clock has 32 KHz
|
|
*/
|
|
reg = WDT_LENGTH_TIMEOUT(timeout << 6) | WDT_LENGTH_KEY;
|
|
iowrite32(reg, wdt_base + WDT_LENGTH);
|
|
|
|
mtk_wdt_ping(wdt_dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int mtk_wdt_stop(struct watchdog_device *wdt_dev)
|
|
{
|
|
struct mtk_wdt_dev *mtk_wdt = watchdog_get_drvdata(wdt_dev);
|
|
void __iomem *wdt_base = mtk_wdt->wdt_base;
|
|
u32 reg;
|
|
|
|
reg = readl(wdt_base + WDT_MODE);
|
|
reg &= ~WDT_MODE_EN;
|
|
reg |= WDT_MODE_KEY;
|
|
iowrite32(reg, wdt_base + WDT_MODE);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int mtk_wdt_start(struct watchdog_device *wdt_dev)
|
|
{
|
|
u32 reg;
|
|
struct mtk_wdt_dev *mtk_wdt = watchdog_get_drvdata(wdt_dev);
|
|
void __iomem *wdt_base = mtk_wdt->wdt_base;
|
|
int ret;
|
|
|
|
ret = mtk_wdt_set_timeout(wdt_dev, wdt_dev->timeout);
|
|
if (ret < 0)
|
|
return ret;
|
|
|
|
reg = ioread32(wdt_base + WDT_MODE);
|
|
reg &= ~(WDT_MODE_IRQ_EN | WDT_MODE_DUAL_EN);
|
|
reg |= (WDT_MODE_EN | WDT_MODE_KEY);
|
|
iowrite32(reg, wdt_base + WDT_MODE);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static const struct watchdog_info mtk_wdt_info = {
|
|
.identity = DRV_NAME,
|
|
.options = WDIOF_SETTIMEOUT |
|
|
WDIOF_KEEPALIVEPING |
|
|
WDIOF_MAGICCLOSE,
|
|
};
|
|
|
|
static const struct watchdog_ops mtk_wdt_ops = {
|
|
.owner = THIS_MODULE,
|
|
.start = mtk_wdt_start,
|
|
.stop = mtk_wdt_stop,
|
|
.ping = mtk_wdt_ping,
|
|
.set_timeout = mtk_wdt_set_timeout,
|
|
.restart = mtk_wdt_restart,
|
|
};
|
|
|
|
static int mtk_wdt_probe(struct platform_device *pdev)
|
|
{
|
|
struct mtk_wdt_dev *mtk_wdt;
|
|
struct resource *res;
|
|
int err;
|
|
|
|
mtk_wdt = devm_kzalloc(&pdev->dev, sizeof(*mtk_wdt), GFP_KERNEL);
|
|
if (!mtk_wdt)
|
|
return -ENOMEM;
|
|
|
|
platform_set_drvdata(pdev, mtk_wdt);
|
|
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
|
mtk_wdt->wdt_base = devm_ioremap_resource(&pdev->dev, res);
|
|
if (IS_ERR(mtk_wdt->wdt_base))
|
|
return PTR_ERR(mtk_wdt->wdt_base);
|
|
|
|
mtk_wdt->wdt_dev.info = &mtk_wdt_info;
|
|
mtk_wdt->wdt_dev.ops = &mtk_wdt_ops;
|
|
mtk_wdt->wdt_dev.timeout = WDT_MAX_TIMEOUT;
|
|
mtk_wdt->wdt_dev.max_timeout = WDT_MAX_TIMEOUT;
|
|
mtk_wdt->wdt_dev.min_timeout = WDT_MIN_TIMEOUT;
|
|
mtk_wdt->wdt_dev.parent = &pdev->dev;
|
|
|
|
watchdog_init_timeout(&mtk_wdt->wdt_dev, timeout, &pdev->dev);
|
|
watchdog_set_nowayout(&mtk_wdt->wdt_dev, nowayout);
|
|
watchdog_set_restart_priority(&mtk_wdt->wdt_dev, 128);
|
|
|
|
watchdog_set_drvdata(&mtk_wdt->wdt_dev, mtk_wdt);
|
|
|
|
mtk_wdt_stop(&mtk_wdt->wdt_dev);
|
|
|
|
err = watchdog_register_device(&mtk_wdt->wdt_dev);
|
|
if (unlikely(err))
|
|
return err;
|
|
|
|
dev_info(&pdev->dev, "Watchdog enabled (timeout=%d sec, nowayout=%d)\n",
|
|
mtk_wdt->wdt_dev.timeout, nowayout);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void mtk_wdt_shutdown(struct platform_device *pdev)
|
|
{
|
|
struct mtk_wdt_dev *mtk_wdt = platform_get_drvdata(pdev);
|
|
|
|
if (watchdog_active(&mtk_wdt->wdt_dev))
|
|
mtk_wdt_stop(&mtk_wdt->wdt_dev);
|
|
}
|
|
|
|
static int mtk_wdt_remove(struct platform_device *pdev)
|
|
{
|
|
struct mtk_wdt_dev *mtk_wdt = platform_get_drvdata(pdev);
|
|
|
|
watchdog_unregister_device(&mtk_wdt->wdt_dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_PM_SLEEP
|
|
static int mtk_wdt_suspend(struct device *dev)
|
|
{
|
|
struct mtk_wdt_dev *mtk_wdt = dev_get_drvdata(dev);
|
|
|
|
if (watchdog_active(&mtk_wdt->wdt_dev))
|
|
mtk_wdt_stop(&mtk_wdt->wdt_dev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int mtk_wdt_resume(struct device *dev)
|
|
{
|
|
struct mtk_wdt_dev *mtk_wdt = dev_get_drvdata(dev);
|
|
|
|
if (watchdog_active(&mtk_wdt->wdt_dev)) {
|
|
mtk_wdt_start(&mtk_wdt->wdt_dev);
|
|
mtk_wdt_ping(&mtk_wdt->wdt_dev);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
static const struct of_device_id mtk_wdt_dt_ids[] = {
|
|
{ .compatible = "mediatek,mt6589-wdt" },
|
|
{ /* sentinel */ }
|
|
};
|
|
MODULE_DEVICE_TABLE(of, mtk_wdt_dt_ids);
|
|
|
|
static const struct dev_pm_ops mtk_wdt_pm_ops = {
|
|
SET_SYSTEM_SLEEP_PM_OPS(mtk_wdt_suspend,
|
|
mtk_wdt_resume)
|
|
};
|
|
|
|
static struct platform_driver mtk_wdt_driver = {
|
|
.probe = mtk_wdt_probe,
|
|
.remove = mtk_wdt_remove,
|
|
.shutdown = mtk_wdt_shutdown,
|
|
.driver = {
|
|
.name = DRV_NAME,
|
|
.pm = &mtk_wdt_pm_ops,
|
|
.of_match_table = mtk_wdt_dt_ids,
|
|
},
|
|
};
|
|
|
|
module_platform_driver(mtk_wdt_driver);
|
|
|
|
module_param(timeout, uint, 0);
|
|
MODULE_PARM_DESC(timeout, "Watchdog heartbeat in seconds");
|
|
|
|
module_param(nowayout, bool, 0);
|
|
MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started (default="
|
|
__MODULE_STRING(WATCHDOG_NOWAYOUT) ")");
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_AUTHOR("Matthias Brugger <matthias.bgg@gmail.com>");
|
|
MODULE_DESCRIPTION("Mediatek WatchDog Timer Driver");
|
|
MODULE_VERSION(DRV_VERSION);
|