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@xxxxxxxxxxx>
---
.../devicetree/bindings/watchdog/samsung-wdt.txt | 21 ++-
drivers/watchdog/Kconfig | 1 +
drivers/watchdog/s3c2410_wdt.c | 145 ++++++++++++++++++--
3 files changed, 157 insertions(+), 10 deletions(-)
diff --git a/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt b/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt
index 2aa486c..5dea363 100644
--- a/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt
+++ b/Documentation/devicetree/bindings/watchdog/samsung-wdt.txt
@@ -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_sys_reg>;
+};
diff --git a/drivers/watchdog/Kconfig b/drivers/watchdog/Kconfig
index d1d53f3..0d272ae 100644
--- a/drivers/watchdog/Kconfig
+++ b/drivers/watchdog/Kconfig
@@ -188,6 +188,7 @@ 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.
diff --git a/drivers/watchdog/s3c2410_wdt.c b/drivers/watchdog/s3c2410_wdt.c
index 23aad7c..42e0fd3 100644
--- a/drivers/watchdog/s3c2410_wdt.c
+++ b/drivers/watchdog/s3c2410_wdt.c
@@ -41,6 +41,8 @@
#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
@@ -61,6 +63,10 @@
#define CONFIG_S3C2410_WATCHDOG_ATBOOT (0)
#define CONFIG_S3C2410_WATCHDOG_DEFAULT_TIME (15)
+#define WDT_DISABLE_REG_OFFSET 0x0408
+#define WDT_MASK_RESET_REG_OFFSET 0x040c
+#define QUIRK_NEEDS_PMU_CONFIG (1 << 0)
+
static bool nowayout = WATCHDOG_NOWAYOUT;
static int tmr_margin;
static int tmr_atboot = CONFIG_S3C2410_WATCHDOG_ATBOOT;
@@ -84,6 +90,13 @@ 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 {
+ int disable_reg;
+ int mask_reset_reg;
+ int mask_bit;
+ u32 quirks;
+};
+
struct s3c2410_wdt {
struct device *dev;
struct clk *clock;
@@ -94,7 +107,49 @@ 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 = WDT_DISABLE_REG_OFFSET,
+ .mask_reset_reg = WDT_MASK_RESET_REG_OFFSET,
+ .mask_bit = 20,
+ .quirks = QUIRK_NEEDS_PMU_CONFIG
+};
+
+static const struct s3c2410_wdt_variant drv_data_exynos5420 = {
+ .disable_reg = WDT_DISABLE_REG_OFFSET,
+ .mask_reset_reg = WDT_MASK_RESET_REG_OFFSET,
+ .mask_bit = 0,
+ .quirks = QUIRK_NEEDS_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 */
@@ -111,6 +166,26 @@ 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;
+
+ if (mask)
+ val = mask_val;
+
+ ret = regmap_update_bits(wdt->pmureg,
+ wdt->drv_data->disable_reg,
+ mask_val, val);
+ if (ret < 0)
+ return ret;
+
+ return regmap_update_bits(wdt->pmureg,
+ wdt->drv_data->mask_reset_reg,
+ mask_val, val);
+}
+
static int s3c2410wdt_keepalive(struct watchdog_device *wdd)
{
struct s3c2410_wdt *wdt = watchdog_get_drvdata(wdd);
@@ -332,6 +407,20 @@ 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;
@@ -354,6 +443,16 @@ 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_NEEDS_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");
@@ -444,6 +543,14 @@ static int s3c2410wdt_probe(struct platform_device *pdev)
(wtcon & S3C2410_WTCON_RSTEN) ? "en" : "dis",
(wtcon & S3C2410_WTCON_INTEN) ? "en" : "dis");
+ if (wdt->drv_data->quirks & QUIRK_NEEDS_PMU_CONFIG) {
+ ret = s3c2410wdt_mask_and_disable_reset(wdt, false);
+ if (ret < 0) {
+ dev_err(wdt->dev, "failed to update pmu register");
