1 files changed, 61 insertions, 0 deletions

diff --git a/arch/arm/mach-omap2/devices.c b/arch/arm/mach-omap2/devices.c
index 5eb0b58b2e95..818452ac905d 100644
--- a/arch/arm/mach-omap2/devices.c
+++ b/arch/arm/mach-omap2/devices.c
@@ -914,11 +914,72 @@ static inline void omap_init_vout(void) {}
 
 /*-------------------------------------------------------------------------*/
 
+/*
+ * Inorder to avoid any assumptions from bootloader regarding WDT
+ * settings, WDT module is reset during init. This enables the watchdog
+ * timer. Hence it is required to disable the watchdog after the WDT reset
+ * during init. Otherwise the system would reboot as per the default
+ * watchdog timer registers settings.
+ */
+#define OMAP_WDT_WPS	(0x34)
+#define OMAP_WDT_SPR	(0x48)
+
+static int omap2_disable_wdt(struct omap_hwmod *oh, void *unused)
+{
+	void __iomem *base;
+	int ret;
+
+	if (!oh) {
+		pr_err("%s: Could not look up wdtimer_hwmod\n", __func__);
+		return -EINVAL;
+	}
+
+	base = omap_hwmod_get_mpu_rt_va(oh);
+	if (!base) {
+		pr_err("%s: Could not get the base address for %s\n",
+				oh->name, __func__);
+		return -EINVAL;
+	}
+
+	/* Enable the clocks before accessing the WDT registers */
+	ret = omap_hwmod_enable(oh);
+	if (ret) {
+		pr_err("%s: Could not enable clocks for %s\n",
+				oh->name, __func__);
+		return ret;
+	}
+
+	/* sequence required to disable watchdog */
+	__raw_writel(0xAAAA, base + OMAP_WDT_SPR);
+	while (__raw_readl(base + OMAP_WDT_WPS) & 0x10)
+		cpu_relax();
+
+	__raw_writel(0x5555, base + OMAP_WDT_SPR);
+	while (__raw_readl(base + OMAP_WDT_WPS) & 0x10)
+		cpu_relax();
+
+	ret = omap_hwmod_idle(oh);
+	if (ret)
+		pr_err("%s: Could not disable clocks for %s\n",
+				oh->name, __func__);
+
+	return ret;
+}
+
+static void __init omap_disable_wdt(void)
+{
+	if (cpu_class_is_omap2())
+		omap_hwmod_for_each_by_class("wd_timer",
+						omap2_disable_wdt, NULL);
+	return;
+}
+
 static int __init omap2_init_devices(void)
 {
 	/* please keep these calls, and their implementations above,
 	 * in alphabetical order so they're easier to sort through.
 	 */
+	omap_disable_wdt();
 	omap_hsmmc_reset();
 	omap_init_camera();
 	omap_init_mbox();