ARM: EXYNOS: Clear SYS_WDTRESET bit to use watchdog reset

When SYS_WDTRESET is set, watchdog timer reset request
is ignored by power management unit.

Signed-off-by: Jonghwan Choi <jhbird.choi@samsung.com>
Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>

2 files changed, 19 insertions, 0 deletions

diff --git a/arch/arm/mach-exynos/include/mach/regs-pmu.h b/arch/arm/mach-exynos/include/mach/regs-pmu.h
index 43a99e6f56ab..d4e392b811a3 100644
--- a/arch/arm/mach-exynos/include/mach/regs-pmu.h
+++ b/arch/arm/mach-exynos/include/mach/regs-pmu.h
@@ -232,6 +232,11 @@
 
 #define EXYNOS5_USB_CFG                                         S5P_PMUREG(0x0230)
 
+#define EXYNOS5_AUTO_WDTRESET_DISABLE                           S5P_PMUREG(0x0408)
+#define EXYNOS5_MASK_WDTRESET_REQUEST                           S5P_PMUREG(0x040C)
+
+#define EXYNOS5_SYS_WDTRESET                                    (1 << 20)
+
 #define EXYNOS5_ARM_CORE0_SYS_PWR_REG                           S5P_PMUREG(0x1000)
 #define EXYNOS5_DIS_IRQ_ARM_CORE0_LOCAL_SYS_PWR_REG             S5P_PMUREG(0x1004)
 #define EXYNOS5_DIS_IRQ_ARM_CORE0_CENTRAL_SYS_PWR_REG           S5P_PMUREG(0x1008)
diff --git a/arch/arm/mach-exynos/pmu.c b/arch/arm/mach-exynos/pmu.c
index 4aacb66f7161..bb4c522f8e05 100644
--- a/arch/arm/mach-exynos/pmu.c
+++ b/arch/arm/mach-exynos/pmu.c
@@ -390,6 +390,8 @@ void exynos_sys_powerdown_conf(enum sys_powerdown mode)
 
 static int __init exynos_pmu_init(void)
 {
+        unsigned int value;
+
         exynos_pmu_config = exynos4210_pmu_config;
 
         if (soc_is_exynos4210()) {
@@ -399,6 +401,18 @@ static int __init exynos_pmu_init(void)
                 exynos_pmu_config = exynos4x12_pmu_config;
                 pr_info("EXYNOS4x12 PMU Initialize\n");
         } else if (soc_is_exynos5250()) {
+                /*
+                 * When SYS_WDTRESET is set, watchdog timer reset request
+                 * is ignored by power management unit.
+                 */
+                value = __raw_readl(EXYNOS5_AUTO_WDTRESET_DISABLE);
+                value &= ~EXYNOS5_SYS_WDTRESET;
+                __raw_writel(value, EXYNOS5_AUTO_WDTRESET_DISABLE);
+
+                value = __raw_readl(EXYNOS5_MASK_WDTRESET_REQUEST);
+                value &= ~EXYNOS5_SYS_WDTRESET;
+                __raw_writel(value, EXYNOS5_MASK_WDTRESET_REQUEST);
+
                 exynos_pmu_config = exynos5250_pmu_config;
                 pr_info("EXYNOS5250 PMU Initialize\n");
         } else {