[PATCH V2 4/6] mpcore_wdt: Fix timer mode setup

Vitaly Kuzmichev vkuzmichev at mvista.com
Tue Jul 5 15:00:38 EDT 2011


Allow watchdog to set its iterrupt as pending when it is configured
for timer mode (in other words, allow emitting interrupt).
Also add macros for all Watchdog Control Register flags.

Signed-off-by: Vitaly Kuzmichev <vkuzmichev at mvista.com>
---
 drivers/watchdog/mpcore_wdt.c |   21 +++++++++++++++++----
 1 files changed, 17 insertions(+), 4 deletions(-)

diff --git a/drivers/watchdog/mpcore_wdt.c b/drivers/watchdog/mpcore_wdt.c
index b330a0a..11c70df 100644
--- a/drivers/watchdog/mpcore_wdt.c
+++ b/drivers/watchdog/mpcore_wdt.c
@@ -42,6 +42,12 @@ unsigned long twd_timer_get_rate(void);
 #define TWD_WDOG_RESETSTAT		0x30
 #define TWD_WDOG_DISABLE		0x34
 
+#define TWD_WDOG_CONTROL_ENABLE		(1 << 0)
+#define TWD_WDOG_CONTROL_PERIODIC	(1 << 1)
+#define TWD_WDOG_CONTROL_IT_ENABLE	(1 << 2)
+#define TWD_WDOG_CONTROL_TIMER_MODE	(0 << 3)
+#define TWD_WDOG_CONTROL_WATCHDOG_MODE	(1 << 3)
+
 struct mpcore_wdt {
 	unsigned long	timer_alive;
 	struct device	*dev;
@@ -125,18 +131,25 @@ static void mpcore_wdt_stop(struct mpcore_wdt *wdt)
 
 static void mpcore_wdt_start(struct mpcore_wdt *wdt)
 {
+	u32 mode;
+
 	dev_printk(KERN_INFO, wdt->dev, "enabling watchdog.\n");
 
 	/* This loads the count register but does NOT start the count yet */
 	mpcore_wdt_keepalive(wdt);
 
+	/* Setup watchdog - prescale=256, enable=1 */
+	mode = (255 << 8) | TWD_WDOG_CONTROL_ENABLE;
+
 	if (mpcore_noboot) {
-		/* Enable watchdog - prescale=256, watchdog mode=0, enable=1 */
-		writel(0x0000FF01, wdt->base + TWD_WDOG_CONTROL);
+		/* timer mode, send interrupt */
+		mode |=	TWD_WDOG_CONTROL_TIMER_MODE
+		     |  TWD_WDOG_CONTROL_IT_ENABLE;
 	} else {
-		/* Enable watchdog - prescale=256, watchdog mode=1, enable=1 */
-		writel(0x0000FF09, wdt->base + TWD_WDOG_CONTROL);
+		/* watchdog mode */
+		mode |=	TWD_WDOG_CONTROL_WATCHDOG_MODE;
 	}
+	writel(mode, wdt->base + TWD_WDOG_CONTROL);
 }
 
 static int mpcore_wdt_set_heartbeat(int t)
-- 
1.7.3.4




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