mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-25 00:34:54 +07:00
c4718308d7
The watchdog might already be running during boot with a timeout set by e.g. the bootloader. Make use of this pre-configured timeout instead of falling back to the default timeout if no device tree value is given. Signed-off-by: Stefan Riedmueller <s.riedmueller@phytec.de> Reviewed-by: Adam Thomson <Adam.Thomson.Opensource@diasemi.com> Reviewed-by: Guenter Roeck <linux@roeck-us.net> Link: https://lore.kernel.org/r/20200403130728.39260-2-s.riedmueller@phytec.de Signed-off-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Wim Van Sebroeck <wim@linux-watchdog.org>
251 lines
6.4 KiB
C
251 lines
6.4 KiB
C
// SPDX-License-Identifier: GPL-2.0+
|
|
/*
|
|
* Watchdog driver for DA9063 PMICs.
|
|
*
|
|
* Copyright(c) 2012 Dialog Semiconductor Ltd.
|
|
*
|
|
* Author: Mariusz Wojtasik <mariusz.wojtasik@diasemi.com>
|
|
*
|
|
*/
|
|
|
|
#include <linux/kernel.h>
|
|
#include <linux/module.h>
|
|
#include <linux/watchdog.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/uaccess.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/delay.h>
|
|
#include <linux/mfd/da9063/registers.h>
|
|
#include <linux/mfd/da9063/core.h>
|
|
#include <linux/regmap.h>
|
|
|
|
/*
|
|
* Watchdog selector to timeout in seconds.
|
|
* 0: WDT disabled;
|
|
* others: timeout = 2048 ms * 2^(TWDSCALE-1).
|
|
*/
|
|
static const unsigned int wdt_timeout[] = { 0, 2, 4, 8, 16, 32, 65, 131 };
|
|
#define DA9063_TWDSCALE_DISABLE 0
|
|
#define DA9063_TWDSCALE_MIN 1
|
|
#define DA9063_TWDSCALE_MAX (ARRAY_SIZE(wdt_timeout) - 1)
|
|
#define DA9063_WDT_MIN_TIMEOUT wdt_timeout[DA9063_TWDSCALE_MIN]
|
|
#define DA9063_WDT_MAX_TIMEOUT wdt_timeout[DA9063_TWDSCALE_MAX]
|
|
#define DA9063_WDG_TIMEOUT wdt_timeout[3]
|
|
#define DA9063_RESET_PROTECTION_MS 256
|
|
|
|
static unsigned int da9063_wdt_timeout_to_sel(unsigned int secs)
|
|
{
|
|
unsigned int i;
|
|
|
|
for (i = DA9063_TWDSCALE_MIN; i <= DA9063_TWDSCALE_MAX; i++) {
|
|
if (wdt_timeout[i] >= secs)
|
|
return i;
|
|
}
|
|
|
|
return DA9063_TWDSCALE_MAX;
|
|
}
|
|
|
|
/*
|
|
* Read the currently active timeout.
|
|
* Zero means the watchdog is disabled.
|
|
*/
|
|
static unsigned int da9063_wdt_read_timeout(struct da9063 *da9063)
|
|
{
|
|
unsigned int val;
|
|
|
|
regmap_read(da9063->regmap, DA9063_REG_CONTROL_D, &val);
|
|
|
|
return wdt_timeout[val & DA9063_TWDSCALE_MASK];
|
|
}
|
|
|
|
static int da9063_wdt_disable_timer(struct da9063 *da9063)
|
|
{
|
|
return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
|
|
DA9063_TWDSCALE_MASK,
|
|
DA9063_TWDSCALE_DISABLE);
|
|
}
|
|
|
|
static int
|
|
da9063_wdt_update_timeout(struct da9063 *da9063, unsigned int timeout)
|
|
{
|
|
unsigned int regval;
|
|
int ret;
|
|
|
|
/*
|
|
* The watchdog triggers a reboot if a timeout value is already
|
|
* programmed because the timeout value combines two functions
|
|
* in one: indicating the counter limit and starting the watchdog.
|
|
* The watchdog must be disabled to be able to change the timeout
|
|
* value if the watchdog is already running. Then we can set the
|
|
* new timeout value which enables the watchdog again.
|
|
*/
|
|
ret = da9063_wdt_disable_timer(da9063);
|
|
if (ret)
|
|
return ret;
|
|
|
|
usleep_range(150, 300);
|
|
regval = da9063_wdt_timeout_to_sel(timeout);
|
|
|
|
return regmap_update_bits(da9063->regmap, DA9063_REG_CONTROL_D,
|
|
DA9063_TWDSCALE_MASK, regval);
|
|
}
|
|
|
|
static int da9063_wdt_start(struct watchdog_device *wdd)
|
|
{
|
|
struct da9063 *da9063 = watchdog_get_drvdata(wdd);
|
|
int ret;
|
|
|
|
ret = da9063_wdt_update_timeout(da9063, wdd->timeout);
|
|
if (ret)
|
|
dev_err(da9063->dev, "Watchdog failed to start (err = %d)\n",
|
|
ret);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int da9063_wdt_stop(struct watchdog_device *wdd)
|
|
{
|
|
struct da9063 *da9063 = watchdog_get_drvdata(wdd);
|
|
int ret;
|
|
|
|
ret = da9063_wdt_disable_timer(da9063);
|
|
if (ret)
|
|
dev_alert(da9063->dev, "Watchdog failed to stop (err = %d)\n",
|
|
ret);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int da9063_wdt_ping(struct watchdog_device *wdd)
|
|
{
|
|
struct da9063 *da9063 = watchdog_get_drvdata(wdd);
|
|
int ret;
|
|
|
|
ret = regmap_write(da9063->regmap, DA9063_REG_CONTROL_F,
|
|
DA9063_WATCHDOG);
|
|
if (ret)
|
|
dev_alert(da9063->dev, "Failed to ping the watchdog (err = %d)\n",
|
|
ret);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int da9063_wdt_set_timeout(struct watchdog_device *wdd,
|
|
unsigned int timeout)
|
|
{
|
|
struct da9063 *da9063 = watchdog_get_drvdata(wdd);
|
|
int ret = 0;
|
|
|
|
/*
|
|
* There are two cases when a set_timeout() will be called:
|
|
* 1. The watchdog is off and someone wants to set the timeout for the
|
|
* further use.
|
|
* 2. The watchdog is already running and a new timeout value should be
|
|
* set.
|
|
*
|
|
* The watchdog can't store a timeout value not equal zero without
|
|
* enabling the watchdog, so the timeout must be buffered by the driver.
|
|
*/
|
|
if (watchdog_active(wdd))
|
|
ret = da9063_wdt_update_timeout(da9063, timeout);
|
|
|
|
if (ret)
|
|
dev_err(da9063->dev, "Failed to set watchdog timeout (err = %d)\n",
|
|
ret);
|
|
else
|
|
wdd->timeout = wdt_timeout[da9063_wdt_timeout_to_sel(timeout)];
|
|
|
|
return ret;
|
|
}
|
|
|
|
static int da9063_wdt_restart(struct watchdog_device *wdd, unsigned long action,
|
|
void *data)
|
|
{
|
|
struct da9063 *da9063 = watchdog_get_drvdata(wdd);
|
|
int ret;
|
|
|
|
ret = regmap_write(da9063->regmap, DA9063_REG_CONTROL_F,
|
|
DA9063_SHUTDOWN);
|
|
if (ret)
|
|
dev_alert(da9063->dev, "Failed to shutdown (err = %d)\n",
|
|
ret);
|
|
|
|
return ret;
|
|
}
|
|
|
|
static const struct watchdog_info da9063_watchdog_info = {
|
|
.options = WDIOF_SETTIMEOUT | WDIOF_KEEPALIVEPING,
|
|
.identity = "DA9063 Watchdog",
|
|
};
|
|
|
|
static const struct watchdog_ops da9063_watchdog_ops = {
|
|
.owner = THIS_MODULE,
|
|
.start = da9063_wdt_start,
|
|
.stop = da9063_wdt_stop,
|
|
.ping = da9063_wdt_ping,
|
|
.set_timeout = da9063_wdt_set_timeout,
|
|
.restart = da9063_wdt_restart,
|
|
};
|
|
|
|
static int da9063_wdt_probe(struct platform_device *pdev)
|
|
{
|
|
struct device *dev = &pdev->dev;
|
|
struct da9063 *da9063;
|
|
struct watchdog_device *wdd;
|
|
unsigned int timeout;
|
|
|
|
if (!dev->parent)
|
|
return -EINVAL;
|
|
|
|
da9063 = dev_get_drvdata(dev->parent);
|
|
if (!da9063)
|
|
return -EINVAL;
|
|
|
|
wdd = devm_kzalloc(dev, sizeof(*wdd), GFP_KERNEL);
|
|
if (!wdd)
|
|
return -ENOMEM;
|
|
|
|
wdd->info = &da9063_watchdog_info;
|
|
wdd->ops = &da9063_watchdog_ops;
|
|
wdd->min_timeout = DA9063_WDT_MIN_TIMEOUT;
|
|
wdd->max_timeout = DA9063_WDT_MAX_TIMEOUT;
|
|
wdd->min_hw_heartbeat_ms = DA9063_RESET_PROTECTION_MS;
|
|
wdd->parent = dev;
|
|
wdd->status = WATCHDOG_NOWAYOUT_INIT_STATUS;
|
|
|
|
watchdog_set_restart_priority(wdd, 128);
|
|
watchdog_set_drvdata(wdd, da9063);
|
|
|
|
wdd->timeout = DA9063_WDG_TIMEOUT;
|
|
|
|
/* Use pre-configured timeout if watchdog is already running. */
|
|
timeout = da9063_wdt_read_timeout(da9063);
|
|
if (timeout)
|
|
wdd->timeout = timeout;
|
|
|
|
/* Set timeout, maybe override it with DT value, scale it */
|
|
watchdog_init_timeout(wdd, 0, dev);
|
|
da9063_wdt_set_timeout(wdd, wdd->timeout);
|
|
|
|
/* Update timeout if the watchdog is already running. */
|
|
if (timeout) {
|
|
da9063_wdt_update_timeout(da9063, wdd->timeout);
|
|
set_bit(WDOG_HW_RUNNING, &wdd->status);
|
|
}
|
|
|
|
return devm_watchdog_register_device(dev, wdd);
|
|
}
|
|
|
|
static struct platform_driver da9063_wdt_driver = {
|
|
.probe = da9063_wdt_probe,
|
|
.driver = {
|
|
.name = DA9063_DRVNAME_WATCHDOG,
|
|
},
|
|
};
|
|
module_platform_driver(da9063_wdt_driver);
|
|
|
|
MODULE_AUTHOR("Mariusz Wojtasik <mariusz.wojtasik@diasemi.com>");
|
|
MODULE_DESCRIPTION("Watchdog driver for Dialog DA9063");
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_ALIAS("platform:" DA9063_DRVNAME_WATCHDOG);
|