1 files changed, 23 insertions, 9 deletions

diff --git a/drivers/watchdog/dw_wdt.c b/drivers/watchdog/dw_wdt.c
index b34a2e4e4e43..d0bb9499d12c 100644
--- a/drivers/watchdog/dw_wdt.c
+++ b/drivers/watchdog/dw_wdt.c
@@ -51,6 +51,8 @@
 /* The maximum TOP (timeout period) value that can be set in the watchdog. */
 #define DW_WDT_MAX_TOP          15
 
+#define DW_WDT_DEFAULT_SECONDS  30
+
 static bool nowayout = WATCHDOG_NOWAYOUT;
 module_param(nowayout, bool, 0);
 MODULE_PARM_DESC(nowayout, "Watchdog cannot be stopped once started "
@@ -96,6 +98,12 @@ static inline void dw_wdt_set_next_heartbeat(void)
         dw_wdt.next_heartbeat = jiffies + dw_wdt_get_top() * HZ;
 }
 
+static void dw_wdt_keepalive(void)
+{
+        writel(WDOG_COUNTER_RESTART_KICK_VALUE, dw_wdt.regs +
+               WDOG_COUNTER_RESTART_REG_OFFSET);
+}
+
 static int dw_wdt_set_top(unsigned top_s)
 {
         int i, top_val = DW_WDT_MAX_TOP;
@@ -110,21 +118,27 @@ static int dw_wdt_set_top(unsigned top_s)
                         break;
                 }
 
-        /* Set the new value in the watchdog. */
+        /*
+         * Set the new value in the watchdog.  Some versions of dw_wdt
+         * have have TOPINIT in the TIMEOUT_RANGE register (as per
+         * CP_WDT_DUAL_TOP in WDT_COMP_PARAMS_1).  On those we
+         * effectively get a pat of the watchdog right here.
+         */
         writel(top_val | top_val << WDOG_TIMEOUT_RANGE_TOPINIT_SHIFT,
                 dw_wdt.regs + WDOG_TIMEOUT_RANGE_REG_OFFSET);
 
+        /*
+         * Add an explicit pat to handle versions of the watchdog that
+         * don't have TOPINIT.  This won't hurt on versions that have
+         * it.
+         */
+        dw_wdt_keepalive();
+
         dw_wdt_set_next_heartbeat();
 
         return dw_wdt_top_in_seconds(top_val);
 }
 
-static void dw_wdt_keepalive(void)
-{
-        writel(WDOG_COUNTER_RESTART_KICK_VALUE, dw_wdt.regs +
-               WDOG_COUNTER_RESTART_REG_OFFSET);
-}
-
 static int dw_wdt_restart_handle(struct notifier_block *this,
                                 unsigned long mode, void *cmd)
 {
@@ -167,9 +181,9 @@ static int dw_wdt_open(struct inode *inode, struct file *filp)
         if (!dw_wdt_is_enabled()) {
                 /*
                  * The watchdog is not currently enabled. Set the timeout to
-                 * the maximum and then start it.
+                 * something reasonable and then start it.
                  */
-                dw_wdt_set_top(DW_WDT_MAX_TOP);
+                dw_wdt_set_top(DW_WDT_DEFAULT_SECONDS);
                 writel(WDOG_CONTROL_REG_WDT_EN_MASK,
                        dw_wdt.regs + WDOG_CONTROL_REG_OFFSET);
         }