watchdog: s3c2410_wdt: use syscon regmap interface to configure pmu register

Add device tree support for exynos5250 and 5420 SoCs and use syscon regmap interface
to configure AUTOMATIC_WDT_RESET_DISABLE and MASK_WDT_RESET_REQUEST registers of PMU
to mask/unmask enable/disable of watchdog in probe and s2r scenarios.

Signed-off-by: Leela Krishna Amudala <l.krishna@samsung.com>
Signed-off-by: Doug Anderson <dianders@chromium.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Wim Van Sebroeck <wim@iguana.be>
This commit is contained in:
Leela Krishna Amudala 2013-12-06 11:17:47 +05:30 committed by Wim Van Sebroeck
parent 178624403c
commit 4f1f653a68
3 changed files with 166 additions and 10 deletions

View File

@ -5,10 +5,29 @@ after a preset amount of time during which the WDT reset event has not
occurred.
Required properties:
- compatible : should be "samsung,s3c2410-wdt"
- compatible : should be one among the following
(a) "samsung,s3c2410-wdt" for Exynos4 and previous SoCs
(b) "samsung,exynos5250-wdt" for Exynos5250
(c) "samsung,exynos5420-wdt" for Exynos5420
- reg : base physical address of the controller and length of memory mapped
region.
- interrupts : interrupt number to the cpu.
- samsung,syscon-phandle : reference to syscon node (This property required only
in case of compatible being "samsung,exynos5250-wdt" or "samsung,exynos5420-wdt".
In case of Exynos5250 and 5420 this property points to syscon node holding the PMU
base address)
Optional properties:
- timeout-sec : contains the watchdog timeout in seconds.
Example:
watchdog@101D0000 {
compatible = "samsung,exynos5250-wdt";
reg = <0x101D0000 0x100>;
interrupts = <0 42 0>;
clocks = <&clock 336>;
clock-names = "watchdog";
samsung,syscon-phandle = <&pmu_syscon>;
};

View File

@ -196,6 +196,7 @@ config S3C2410_WATCHDOG
tristate "S3C2410 Watchdog"
depends on HAVE_S3C2410_WATCHDOG
select WATCHDOG_CORE
select MFD_SYSCON if ARCH_EXYNOS5
help
Watchdog timer block in the Samsung SoCs. This will reboot
the system when the timer expires with the watchdog enabled.

View File

@ -40,6 +40,8 @@
#include <linux/slab.h>
#include <linux/err.h>
#include <linux/of.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
#define S3C2410_WTCON 0x00
#define S3C2410_WTDAT 0x04
@ -60,6 +62,10 @@
#define CONFIG_S3C2410_WATCHDOG_ATBOOT (0)
#define CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME (15)
#define EXYNOS5_WDT_DISABLE_REG_OFFSET 0x0408
#define EXYNOS5_WDT_MASK_RESET_REG_OFFSET 0x040c
#define QUIRK_HAS_PMU_CONFIG (1 << 0)
static bool nowayout = WATCHDOG_NOWAYOUT;
static int tmr_margin;
static int tmr_atboot = CONFIG_S3C2410_WATCHDOG_ATBOOT;
@ -83,6 +89,25 @@ MODULE_PARM_DESC(soft_noboot, "Watchdog action, set to 1 to ignore reboots, "
"0 to reboot (default 0)");
MODULE_PARM_DESC(debug, "Watchdog debug, set to >1 for debug (default 0)");
/**
* struct s3c2410_wdt_variant - Per-variant config data
*
* @disable_reg: Offset in pmureg for the register that disables the watchdog
* timer reset functionality.
* @mask_reset_reg: Offset in pmureg for the register that masks the watchdog
* timer reset functionality.
* @mask_bit: Bit number for the watchdog timer in the disable register and the
* mask reset register.
* @quirks: A bitfield of quirks.
*/
struct s3c2410_wdt_variant {
int disable_reg;
int mask_reset_reg;
int mask_bit;
u32 quirks;
};
struct s3c2410_wdt {
struct device *dev;
struct clk *clock;
@ -93,8 +118,50 @@ struct s3c2410_wdt {
unsigned long wtdat_save;
struct watchdog_device wdt_device;
struct notifier_block freq_transition;
struct s3c2410_wdt_variant *drv_data;
struct regmap *pmureg;
};
static const struct s3c2410_wdt_variant drv_data_s3c2410 = {
.quirks = 0
};
#ifdef CONFIG_OF
static const struct s3c2410_wdt_variant drv_data_exynos5250 = {
.disable_reg = EXYNOS5_WDT_DISABLE_REG_OFFSET,
.mask_reset_reg = EXYNOS5_WDT_MASK_RESET_REG_OFFSET,
.mask_bit = 20,
.quirks = QUIRK_HAS_PMU_CONFIG
};
static const struct s3c2410_wdt_variant drv_data_exynos5420 = {
.disable_reg = EXYNOS5_WDT_DISABLE_REG_OFFSET,
.mask_reset_reg = EXYNOS5_WDT_MASK_RESET_REG_OFFSET,
.mask_bit = 0,
.quirks = QUIRK_HAS_PMU_CONFIG
};
static const struct of_device_id s3c2410_wdt_match[] = {
{ .compatible = "samsung,s3c2410-wdt",
.data = &drv_data_s3c2410 },
{ .compatible = "samsung,exynos5250-wdt",
.data = &drv_data_exynos5250 },
{ .compatible = "samsung,exynos5420-wdt",
.data = &drv_data_exynos5420 },
{},
};
MODULE_DEVICE_TABLE(of, s3c2410_wdt_match);
#endif
static const struct platform_device_id s3c2410_wdt_ids[] = {
{
.name = "s3c2410-wdt",
.driver_data = (unsigned long)&drv_data_s3c2410,
},
{}
};
MODULE_DEVICE_TABLE(platform, s3c2410_wdt_ids);
/* watchdog control routines */
#define DBG(fmt, ...) \
@ -110,6 +177,35 @@ static inline struct s3c2410_wdt *freq_to_wdt(struct notifier_block *nb)
return container_of(nb, struct s3c2410_wdt, freq_transition);
}
static int s3c2410wdt_mask_and_disable_reset(struct s3c2410_wdt *wdt, bool mask)
{
int ret;
u32 mask_val = 1 << wdt->drv_data->mask_bit;
u32 val = 0;
/* No need to do anything if no PMU CONFIG needed */
if (!(wdt->drv_data->quirks & QUIRK_HAS_PMU_CONFIG))
return 0;
if (mask)
val = mask_val;
ret = regmap_update_bits(wdt->pmureg,
wdt->drv_data->disable_reg,
mask_val, val);
if (ret < 0)
goto error;
ret = regmap_update_bits(wdt->pmureg,
wdt->drv_data->mask_reset_reg,
mask_val, val);
error:
if (ret < 0)
dev_err(wdt->dev, "failed to update reg(%d)\n", ret);
return ret;
}
static int s3c2410wdt_keepalive(struct watchdog_device *wdd)
{
struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
@ -328,6 +424,20 @@ static inline void s3c2410wdt_cpufreq_deregister(struct s3c2410_wdt *wdt)
}
#endif
/* s3c2410_get_wdt_driver_data */
static inline struct s3c2410_wdt_variant *
get_wdt_drv_data(struct platform_device *pdev)
{
if (pdev->dev.of_node) {
const struct of_device_id *match;
match = of_match_node(s3c2410_wdt_match, pdev->dev.of_node);
return (struct s3c2410_wdt_variant *)match->data;
} else {
return (struct s3c2410_wdt_variant *)
platform_get_device_id(pdev)->driver_data;
}
}
static int s3c2410wdt_probe(struct platform_device *pdev)
{
struct device *dev;
@ -350,6 +460,16 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
spin_lock_init(&wdt->lock);
wdt->wdt_device = s3c2410_wdd;
wdt->drv_data = get_wdt_drv_data(pdev);
if (wdt->drv_data->quirks & QUIRK_HAS_PMU_CONFIG) {
wdt->pmureg = syscon_regmap_lookup_by_phandle(dev->of_node,
"samsung,syscon-phandle");
if (IS_ERR(wdt->pmureg)) {
dev_err(dev, "syscon regmap lookup failed.\n");
return PTR_ERR(wdt->pmureg);
}
}
wdt_irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (wdt_irq == NULL) {
dev_err(dev, "no irq resource specified\n");
@ -418,6 +538,10 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
goto err_cpufreq;
}
ret = s3c2410wdt_mask_and_disable_reset(wdt, false);
if (ret < 0)
goto err_unregister;
if (tmr_atboot && started == 0) {
dev_info(dev, "starting watchdog timer\n");
s3c2410wdt_start(&wdt->wdt_device);
@ -442,6 +566,9 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
return 0;
err_unregister:
watchdog_unregister_device(&wdt->wdt_device);
err_cpufreq:
s3c2410wdt_cpufreq_deregister(wdt);
@ -455,8 +582,13 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
static int s3c2410wdt_remove(struct platform_device *dev)
{
int ret;
struct s3c2410_wdt *wdt = platform_get_drvdata(dev);
ret = s3c2410wdt_mask_and_disable_reset(wdt, true);
if (ret < 0)
return ret;
watchdog_unregister_device(&wdt->wdt_device);
s3c2410wdt_cpufreq_deregister(wdt);
@ -471,6 +603,8 @@ static void s3c2410wdt_shutdown(struct platform_device *dev)
{
struct s3c2410_wdt *wdt = platform_get_drvdata(dev);
s3c2410wdt_mask_and_disable_reset(wdt, true);
s3c2410wdt_stop(&wdt->wdt_device);
}
@ -478,12 +612,17 @@ static void s3c2410wdt_shutdown(struct platform_device *dev)
static int s3c2410wdt_suspend(struct device *dev)
{
int ret;
struct s3c2410_wdt *wdt = dev_get_drvdata(dev);
/* Save watchdog state, and turn it off. */
wdt->wtcon_save = readl(wdt->reg_base + S3C2410_WTCON);
wdt->wtdat_save = readl(wdt->reg_base + S3C2410_WTDAT);
ret = s3c2410wdt_mask_and_disable_reset(wdt, true);
if (ret < 0)
return ret;
/* Note that WTCNT doesn't need to be saved. */
s3c2410wdt_stop(&wdt->wdt_device);
@ -492,6 +631,7 @@ static int s3c2410wdt_suspend(struct device *dev)
static int s3c2410wdt_resume(struct device *dev)
{
int ret;
struct s3c2410_wdt *wdt = dev_get_drvdata(dev);
/* Restore watchdog state. */
@ -499,6 +639,10 @@ static int s3c2410wdt_resume(struct device *dev)
writel(wdt->wtdat_save, wdt->reg_base + S3C2410_WTCNT);/* Reset count */
writel(wdt->wtcon_save, wdt->reg_base + S3C2410_WTCON);
ret = s3c2410wdt_mask_and_disable_reset(wdt, false);
if (ret < 0)
return ret;
dev_info(dev, "watchdog %sabled\n",
(wdt->wtcon_save & S3C2410_WTCON_ENABLE) ? "en" : "dis");
@ -509,18 +653,11 @@ static int s3c2410wdt_resume(struct device *dev)
static SIMPLE_DEV_PM_OPS(s3c2410wdt_pm_ops, s3c2410wdt_suspend,
s3c2410wdt_resume);
#ifdef CONFIG_OF
static const struct of_device_id s3c2410_wdt_match[] = {
{ .compatible = "samsung,s3c2410-wdt" },
{},
};
MODULE_DEVICE_TABLE(of, s3c2410_wdt_match);
#endif
static struct platform_driver s3c2410wdt_driver = {
.probe = s3c2410wdt_probe,
.remove = s3c2410wdt_remove,
.shutdown = s3c2410wdt_shutdown,
.id_table = s3c2410_wdt_ids,
.driver = {
.owner = THIS_MODULE,
.name = "s3c2410-wdt",
@ -535,4 +672,3 @@ MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>, "
"Dimitry Andric <dimitry.andric@tomtom.com>");
MODULE_DESCRIPTION("S3C2410 Watchdog Device Driver");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:s3c2410-wdt");