openwrt-xburst/target/linux/brcm47xx/patches-3.0/900-bcm47xx_wdt-noprescale.patch

--- a/drivers/watchdog/bcm47xx_wdt.c
+++ b/drivers/watchdog/bcm47xx_wdt.c
@@ -31,6 +31,7 @@
 
 #define WDT_DEFAULT_TIME	30	/* seconds */
 #define WDT_MAX_TIME		255	/* seconds */
+#define WDT_SHIFT		15	/* 32.768 KHz on cores with slow WDT clock */
 
 static int wdt_time = WDT_DEFAULT_TIME;
 static int nowayout = WATCHDOG_NOWAYOUT;
@@ -50,20 +51,20 @@ static unsigned long bcm47xx_wdt_busy;
 static char expect_release;
 static struct timer_list wdt_timer;
 static atomic_t ticks;
+static int needs_sw_scale;
 
-static inline void bcm47xx_wdt_hw_start(void)
+static inline void bcm47xx_wdt_hw_start(u32 ticks)
 {
-	/* this is 2,5s on 100Mhz clock  and 2s on 133 Mhz */
 	switch (bcm47xx_bus_type) {
 #ifdef CONFIG_BCM47XX_SSB
 	case BCM47XX_BUS_TYPE_SSB:
-		ssb_watchdog_timer_set(&bcm47xx_bus.ssb, 0xfffffff);
+		ssb_watchdog_timer_set(&bcm47xx_bus.ssb, ticks);
 		break;
 #endif
 #ifdef CONFIG_BCM47XX_BCMA
 	case BCM47XX_BUS_TYPE_BCMA:
 		bcma_chipco_watchdog_timer_set(&bcm47xx_bus.bcma.bus.drv_cc,
-					       0xfffffff);
+					       ticks);
 		break;
 #endif
 	}
@@ -88,33 +89,34 @@ static inline int bcm47xx_wdt_hw_stop(vo
 static void bcm47xx_timer_tick(unsigned long unused)
 {
 	if (!atomic_dec_and_test(&ticks)) {
-		bcm47xx_wdt_hw_start();
+		/* This is 2,5s on 100Mhz clock and 2s on 133 Mhz */
+		bcm47xx_wdt_hw_start(0xfffffff);
 		mod_timer(&wdt_timer, jiffies + HZ);
 	} else {
-		printk(KERN_CRIT DRV_NAME "Watchdog will fire soon!!!\n");
+		printk(KERN_CRIT DRV_NAME ": Watchdog will fire soon!!!\n");
 	}
 }
 
-static inline void bcm47xx_wdt_pet(void)
+static void bcm47xx_wdt_pet(void)
 {
-	atomic_set(&ticks, wdt_time);
+	if(needs_sw_scale)
+		atomic_set(&ticks, wdt_time);
+	else
+		bcm47xx_wdt_hw_start(wdt_time << WDT_SHIFT);
 }
 
 static void bcm47xx_wdt_start(void)
 {
 	bcm47xx_wdt_pet();
-	bcm47xx_timer_tick(0);
-}
-
-static void bcm47xx_wdt_pause(void)
-{
-	del_timer_sync(&wdt_timer);
-	bcm47xx_wdt_hw_stop();
+	if(needs_sw_scale)
+		bcm47xx_timer_tick(0);
 }
 
 static void bcm47xx_wdt_stop(void)
 {
-	bcm47xx_wdt_pause();
+	if(needs_sw_scale)
+		del_timer_sync(&wdt_timer);
+	bcm47xx_wdt_hw_stop();
 }
 
 static int bcm47xx_wdt_settimeout(int new_time)
@@ -266,7 +268,20 @@ static int __init bcm47xx_wdt_init(void)
 	if (bcm47xx_wdt_hw_stop() < 0)
 		return -ENODEV;
 
-	setup_timer(&wdt_timer, bcm47xx_timer_tick, 0L);
+	/* FIXME Other cores */
+#ifdef BCM47XX_BUS_TYPE_BCMA
+	if(bcm47xx_bus_type == BCM47XX_BUS_TYPE_BCMA &&
+	   bcm47xx_bus.ssb.chip_id == 0x5354) {
+		/* Slow WDT clock, no pre-scaling */
+		needs_sw_scale = 0;
+	} else {
+#endif
+		/* Fast WDT clock, needs software pre-scaling */
+		needs_sw_scale = 1;
+		setup_timer(&wdt_timer, bcm47xx_timer_tick, 0L);
+#ifdef BCM47XX_BUS_TYPE_BCMA
+	}
+#endif
 
 	if (bcm47xx_wdt_settimeout(wdt_time)) {
 		bcm47xx_wdt_settimeout(WDT_DEFAULT_TIME);