337 lines
8.6 KiB
C
337 lines
8.6 KiB
C
|
/*
|
||
|
|
* sunxi Watchdog Driver
|
||
|
|
*
|
||
|
|
* Copyright (c) 2013 Carlo Caione
|
||
|
|
* 2012 Henrik Nordstrom
|
||
|
|
*
|
||
|
|
* 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.
|
||
|
|
*
|
||
|
|
* Based on xen_wdt.c
|
||
|
|
* (c) Copyright 2010 Novell, Inc.
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <linux/clk.h>
|
||
|
|
#include <linux/delay.h>
|
||
|
|
#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/notifier.h>
|
||
|
|
#include <linux/of.h>
|
||
|
|
#include <linux/of_device.h>
|
||
|
|
#include <linux/platform_device.h>
|
||
|
|
#include <linux/reboot.h>
|
||
|
|
#include <linux/types.h>
|
||
|
|
#include <linux/watchdog.h>
|
||
|
|
|
||
|
|
#define WDT_MAX_TIMEOUT 16
|
||
|
|
#define WDT_MIN_TIMEOUT 1
|
||
|
|
#define WDT_TIMEOUT_MASK 0x0F
|
||
|
|
|
||
|
|
#define WDT_CTRL_RELOAD ((1 << 0) | (0x0a57 << 1))
|
||
|
|
|
||
|
|
#define WDT_MODE_EN (1 << 0)
|
||
|
|
|
||
|
|
#define DRV_NAME "sunxi-wdt"
|
||
|
|
#define DRV_VERSION "1.0"
|
||
|
|
|
||
|
|
static bool nowayout = WATCHDOG_NOWAYOUT;
|
||
|
|
static unsigned int timeout = WDT_MAX_TIMEOUT;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* This structure stores the register offsets for different variants
|
||
|
|
* of Allwinner's watchdog hardware.
|
||
|
|
*/
|
||
|
|
struct sunxi_wdt_reg {
|
||
|
|
u8 wdt_ctrl;
|
||
|
|
u8 wdt_cfg;
|
||
|
|
u8 wdt_mode;
|
||
|
|
u8 wdt_timeout_shift;
|
||
|
|
u8 wdt_reset_mask;
|
||
|
|
u8 wdt_reset_val;
|
||
|
|
};
|
||
|
|
|
||
|
|
struct sunxi_wdt_dev {
|
||
|
|
struct watchdog_device wdt_dev;
|
||
|
|
void __iomem *wdt_base;
|
||
|
|
const struct sunxi_wdt_reg *wdt_regs;
|
||
|
|
struct notifier_block restart_handler;
|
||
|
|
};
|
||
|
|
|
||
|
|
/*
|
||
|
|
* wdt_timeout_map maps the watchdog timer interval value in seconds to
|
||
|
|
* the value of the register WDT_MODE at bits .wdt_timeout_shift ~ +3
|
||
|
|
*
|
||
|
|
* [timeout seconds] = register value
|
||
|
|
*
|
||
|
|
*/
|
||
|
|
|
||
|
|
static const int wdt_timeout_map[] = {
|
||
|
|
[1] = 0x1, /* 1s */
|
||
|
|
[2] = 0x2, /* 2s */
|
||
|
|
[3] = 0x3, /* 3s */
|
||
|
|
[4] = 0x4, /* 4s */
|
||
|
|
[5] = 0x5, /* 5s */
|
||
|
|
[6] = 0x6, /* 6s */
|
||
|
|
[8] = 0x7, /* 8s */
|
||
|
|
[10] = 0x8, /* 10s */
|
||
|
|
[12] = 0x9, /* 12s */
|
||
|
|
[14] = 0xA, /* 14s */
|
||
|
|
[16] = 0xB, /* 16s */
|
||
|
|
};
|
||
|
|
|
||
|
|
|
||
|
|
static int sunxi_restart_handle(struct notifier_block *this, unsigned long mode,
|
||
|
|
void *cmd)
|
||
|
|
{
|
||
|
|
struct sunxi_wdt_dev *sunxi_wdt = container_of(this,
|
||
|
|
struct sunxi_wdt_dev,
|
||
|
|
restart_handler);
|
||
|
|
void __iomem *wdt_base = sunxi_wdt->wdt_base;
|
||
|
|
const struct sunxi_wdt_reg *regs = sunxi_wdt->wdt_regs;
|
||
|
|
u32 val;
|
||
|
|
|
||
|
|
/* Set system reset function */
|
||
|
|
val = readl(wdt_base + regs->wdt_cfg);
|
||
|
|
val &= ~(regs->wdt_reset_mask);
|
||
|
|
val |= regs->wdt_reset_val;
|
||
|
|
writel(val, wdt_base + regs->wdt_cfg);
|
||
|
|
|
||
|
|
/* Set lowest timeout and enable watchdog */
|
||
|
|
val = readl(wdt_base + regs->wdt_mode);
|
||
|
|
val &= ~(WDT_TIMEOUT_MASK << regs->wdt_timeout_shift);
|
||
|
|
val |= WDT_MODE_EN;
|
||
|
|
writel(val, wdt_base + regs->wdt_mode);
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Restart the watchdog. The default (and lowest) interval
|
||
|
|
* value for the watchdog is 0.5s.
|
||
|
|
*/
|
||
|
|
writel(WDT_CTRL_RELOAD, wdt_base + regs->wdt_ctrl);
|
||
|
|
|
||
|
|
while (1) {
|
||
|
|
mdelay(5);
|
||
|
|
val = readl(wdt_base + regs->wdt_mode);
|
||
|
|
val |= WDT_MODE_EN;
|
||
|
|
writel(val, wdt_base + regs->wdt_mode);
|
||
|
|
}
|
||
|
|
return NOTIFY_DONE;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int sunxi_wdt_ping(struct watchdog_device *wdt_dev)
|
||
|
|
{
|
||
|
|
struct sunxi_wdt_dev *sunxi_wdt = watchdog_get_drvdata(wdt_dev);
|
||
|
|
void __iomem *wdt_base = sunxi_wdt->wdt_base;
|
||
|
|
const struct sunxi_wdt_reg *regs = sunxi_wdt->wdt_regs;
|
||
|
|
|
||
|
|
writel(WDT_CTRL_RELOAD, wdt_base + regs->wdt_ctrl);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int sunxi_wdt_set_timeout(struct watchdog_device *wdt_dev,
|
||
|
|
unsigned int timeout)
|
||
|
|
{
|
||
|
|
struct sunxi_wdt_dev *sunxi_wdt = watchdog_get_drvdata(wdt_dev);
|
||
|
|
void __iomem *wdt_base = sunxi_wdt->wdt_base;
|
||
|
|
const struct sunxi_wdt_reg *regs = sunxi_wdt->wdt_regs;
|
||
|
|
u32 reg;
|
||
|
|
|
||
|
|
if (wdt_timeout_map[timeout] == 0)
|
||
|
|
timeout++;
|
||
|
|
|
||
|
|
sunxi_wdt->wdt_dev.timeout = timeout;
|
||
|
|
|
||
|
|
reg = readl(wdt_base + regs->wdt_mode);
|
||
|
|
reg &= ~(WDT_TIMEOUT_MASK << regs->wdt_timeout_shift);
|
||
|
|
reg |= wdt_timeout_map[timeout] << regs->wdt_timeout_shift;
|
||
|
|
writel(reg, wdt_base + regs->wdt_mode);
|
||
|
|
|
||
|
|
sunxi_wdt_ping(wdt_dev);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int sunxi_wdt_stop(struct watchdog_device *wdt_dev)
|
||
|
|
{
|
||
|
|
struct sunxi_wdt_dev *sunxi_wdt = watchdog_get_drvdata(wdt_dev);
|
||
|
|
void __iomem *wdt_base = sunxi_wdt->wdt_base;
|
||
|
|
const struct sunxi_wdt_reg *regs = sunxi_wdt->wdt_regs;
|
||
|
|
|
||
|
|
writel(0, wdt_base + regs->wdt_mode);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int sunxi_wdt_start(struct watchdog_device *wdt_dev)
|
||
|
|
{
|
||
|
|
u32 reg;
|
||
|
|
struct sunxi_wdt_dev *sunxi_wdt = watchdog_get_drvdata(wdt_dev);
|
||
|
|
void __iomem *wdt_base = sunxi_wdt->wdt_base;
|
||
|
|
const struct sunxi_wdt_reg *regs = sunxi_wdt->wdt_regs;
|
||
|
|
int ret;
|
||
|
|
|
||
|
|
ret = sunxi_wdt_set_timeout(&sunxi_wdt->wdt_dev,
|
||
|
|
sunxi_wdt->wdt_dev.timeout);
|
||
|
|
if (ret < 0)
|
||
|
|
return ret;
|
||
|
|
|
||
|
|
/* Set system reset function */
|
||
|
|
reg = readl(wdt_base + regs->wdt_cfg);
|
||
|
|
reg &= ~(regs->wdt_reset_mask);
|
||
|
|
reg |= ~(regs->wdt_reset_val);
|
||
|
|
writel(reg, wdt_base + regs->wdt_cfg);
|
||
|
|
|
||
|
|
/* Enable watchdog */
|
||
|
|
reg = readl(wdt_base + regs->wdt_mode);
|
||
|
|
reg |= WDT_MODE_EN;
|
||
|
|
writel(reg, wdt_base + regs->wdt_mode);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static const struct watchdog_info sunxi_wdt_info = {
|
||
|
|
.identity = DRV_NAME,
|
||
|
|
.options = WDIOF_SETTIMEOUT |
|
||
|
|
WDIOF_KEEPALIVEPING |
|
||
|
|
WDIOF_MAGICCLOSE,
|
||
|
|
};
|
||
|
|
|
||
|
|
static const struct watchdog_ops sunxi_wdt_ops = {
|
||
|
|
.owner = THIS_MODULE,
|
||
|
|
.start = sunxi_wdt_start,
|
||
|
|
.stop = sunxi_wdt_stop,
|
||
|
|
.ping = sunxi_wdt_ping,
|
||
|
|
.set_timeout = sunxi_wdt_set_timeout,
|
||
|
|
};
|
||
|
|
|
||
|
|
static const struct sunxi_wdt_reg sun4i_wdt_reg = {
|
||
|
|
.wdt_ctrl = 0x00,
|
||
|
|
.wdt_cfg = 0x04,
|
||
|
|
.wdt_mode = 0x04,
|
||
|
|
.wdt_timeout_shift = 3,
|
||
|
|
.wdt_reset_mask = 0x02,
|
||
|
|
.wdt_reset_val = 0x02,
|
||
|
|
};
|
||
|
|
|
||
|
|
static const struct sunxi_wdt_reg sun6i_wdt_reg = {
|
||
|
|
.wdt_ctrl = 0x10,
|
||
|
|
.wdt_cfg = 0x14,
|
||
|
|
.wdt_mode = 0x18,
|
||
|
|
.wdt_timeout_shift = 4,
|
||
|
|
.wdt_reset_mask = 0x03,
|
||
|
|
.wdt_reset_val = 0x01,
|
||
|
|
};
|
||
|
|
|
||
|
|
static const struct of_device_id sunxi_wdt_dt_ids[] = {
|
||
|
|
{ .compatible = "allwinner,sun4i-a10-wdt", .data = &sun4i_wdt_reg },
|
||
|
|
{ .compatible = "allwinner,sun6i-a31-wdt", .data = &sun6i_wdt_reg },
|
||
|
|
{ /* sentinel */ }
|
||
|
|
};
|
||
|
|
MODULE_DEVICE_TABLE(of, sunxi_wdt_dt_ids);
|
||
|
|
|
||
|
|
static int sunxi_wdt_probe(struct platform_device *pdev)
|
||
|
|
{
|
||
|
|
struct sunxi_wdt_dev *sunxi_wdt;
|
||
|
|
const struct of_device_id *device;
|
||
|
|
struct resource *res;
|
||
|
|
int err;
|
||
|
|
|
||
|
|
sunxi_wdt = devm_kzalloc(&pdev->dev, sizeof(*sunxi_wdt), GFP_KERNEL);
|
||
|
|
if (!sunxi_wdt)
|
||
|
|
return -EINVAL;
|
||
|
|
|
||
|
|
platform_set_drvdata(pdev, sunxi_wdt);
|
||
|
|
|
||
|
|
device = of_match_device(sunxi_wdt_dt_ids, &pdev->dev);
|
||
|
|
if (!device)
|
||
|
|
return -ENODEV;
|
||
|
|
|
||
|
|
sunxi_wdt->wdt_regs = device->data;
|
||
|
|
|
||
|
|
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
|
||
|
|
sunxi_wdt->wdt_base = devm_ioremap_resource(&pdev->dev, res);
|
||
|
|
if (IS_ERR(sunxi_wdt->wdt_base))
|
||
|
|
return PTR_ERR(sunxi_wdt->wdt_base);
|
||
|
|
|
||
|
|
sunxi_wdt->wdt_dev.info = &sunxi_wdt_info;
|
||
|
|
sunxi_wdt->wdt_dev.ops = &sunxi_wdt_ops;
|
||
|
|
sunxi_wdt->wdt_dev.timeout = WDT_MAX_TIMEOUT;
|
||
|
|
sunxi_wdt->wdt_dev.max_timeout = WDT_MAX_TIMEOUT;
|
||
|
|
sunxi_wdt->wdt_dev.min_timeout = WDT_MIN_TIMEOUT;
|
||
|
|
sunxi_wdt->wdt_dev.parent = &pdev->dev;
|
||
|
|
|
||
|
|
watchdog_init_timeout(&sunxi_wdt->wdt_dev, timeout, &pdev->dev);
|
||
|
|
watchdog_set_nowayout(&sunxi_wdt->wdt_dev, nowayout);
|
||
|
|
|
||
|
|
watchdog_set_drvdata(&sunxi_wdt->wdt_dev, sunxi_wdt);
|
||
|
|
|
||
|
|
sunxi_wdt_stop(&sunxi_wdt->wdt_dev);
|
||
|
|
|
||
|
|
err = watchdog_register_device(&sunxi_wdt->wdt_dev);
|
||
|
|
if (unlikely(err))
|
||
|
|
return err;
|
||
|
|
|
||
|
|
sunxi_wdt->restart_handler.notifier_call = sunxi_restart_handle;
|
||
|
|
sunxi_wdt->restart_handler.priority = 128;
|
||
|
|
err = register_restart_handler(&sunxi_wdt->restart_handler);
|
||
|
|
if (err)
|
||
|
|
dev_err(&pdev->dev,
|
||
|
|
"cannot register restart handler (err=%d)\n", err);
|
||
|
|
|
||
|
|
dev_info(&pdev->dev, "Watchdog enabled (timeout=%d sec, nowayout=%d)",
|
||
|
|
sunxi_wdt->wdt_dev.timeout, nowayout);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static int sunxi_wdt_remove(struct platform_device *pdev)
|
||
|
|
{
|
||
|
|
struct sunxi_wdt_dev *sunxi_wdt = platform_get_drvdata(pdev);
|
||
|
|
|
||
|
|
unregister_restart_handler(&sunxi_wdt->restart_handler);
|
||
|
|
|
||
|
|
watchdog_unregister_device(&sunxi_wdt->wdt_dev);
|
||
|
|
watchdog_set_drvdata(&sunxi_wdt->wdt_dev, NULL);
|
||
|
|
|
||
|
|
return 0;
|
||
|
|
}
|
||
|
|
|
||
|
|
static void sunxi_wdt_shutdown(struct platform_device *pdev)
|
||
|
|
{
|
||
|
|
struct sunxi_wdt_dev *sunxi_wdt = platform_get_drvdata(pdev);
|
||
|
|
|
||
|
|
sunxi_wdt_stop(&sunxi_wdt->wdt_dev);
|
||
|
|
}
|
||
|
|
|
||
|
|
static struct platform_driver sunxi_wdt_driver = {
|
||
|
|
.probe = sunxi_wdt_probe,
|
||
|
|
.remove = sunxi_wdt_remove,
|
||
|
|
.shutdown = sunxi_wdt_shutdown,
|
||
|
|
.driver = {
|
||
|
|
.owner = THIS_MODULE,
|
||
|
|
.name = DRV_NAME,
|
||
|
|
.of_match_table = sunxi_wdt_dt_ids,
|
||
|
|
},
|
||
|
|
};
|
||
|
|
|
||
|
|
module_platform_driver(sunxi_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("Carlo Caione <carlo.caione@gmail.com>");
|
||
|
|
MODULE_AUTHOR("Henrik Nordstrom <henrik@henriknordstrom.net>");
|
||
|
|
MODULE_DESCRIPTION("sunxi WatchDog Timer Driver");
|
||
|
|
MODULE_VERSION(DRV_VERSION);
|