Feed the watchdog in u-boot for 8610 board.

The watchdog on 8610 board is enabled by setting sw[6]
to on. Once enabled, the watchdog can not be disabled
by software. So feed the dog in u-boot is necessary for
normal operation.

Signed-off-by: Jason Jin <Jason.jin@freescale.com>
diff --git a/cpu/mpc86xx/cpu.c b/cpu/mpc86xx/cpu.c
index e26bf36..4a9905d 100644
--- a/cpu/mpc86xx/cpu.c
+++ b/cpu/mpc86xx/cpu.c
@@ -214,6 +214,20 @@
 void
 watchdog_reset(void)
 {
+#if defined(CONFIG_MPC8610)
+	/*
+	 * This actually feed the hard enabled watchdog.
+	 */
+	volatile immap_t *immap = (immap_t *)CFG_IMMR;
+	volatile ccsr_wdt_t *wdt = &immap->im_wdt;
+	volatile ccsr_gur_t *gur = &immap->im_gur;
+	u32 tmp = gur->pordevsr;
+
+	if (tmp & 0x4000) {
+		wdt->swsrr = 0x556c;
+		wdt->swsrr = 0xaa39;
+	}
+#endif
 }
 #endif	/* CONFIG_WATCHDOG */
 
diff --git a/cpu/mpc86xx/interrupts.c b/cpu/mpc86xx/interrupts.c
index d9f634f..f16744b 100644
--- a/cpu/mpc86xx/interrupts.c
+++ b/cpu/mpc86xx/interrupts.c
@@ -36,6 +36,7 @@
 #include <command.h>
 #include <asm/processor.h>
 #include <ppc_asm.tmpl>
+#include <watchdog.h>
 
 unsigned long decrementer_count;    /* count value for 1e6/HZ microseconds */
 unsigned long timestamp;