[U-Boot] [PATCH v2 2/2]: arm:kirkwood: Add hardware watchdog support for Marvell Kirkwood boards

[Simon Kagstrom]

Initialize by calling the generic API watchdog_enable() with the number
of seconds for the watchdog to timeout. It's not possible to disable the
watchdog once it's on.

Signed-off-by: Simon Kagstrom <simon.kagstrom at netinsight.net>
---
ChangeLog:
  v2:
     * Remove watchdog_disable()
     * Add check to see that the maximum timeout supported by the hardware
       is not exceeded

 cpu/arm926ejs/kirkwood/timer.c |   38 ++++++++++++++++++++++++++++++++++++++
 1 files changed, 38 insertions(+), 0 deletions(-)

diff --git a/cpu/arm926ejs/kirkwood/timer.c b/cpu/arm926ejs/kirkwood/timer.c
index 817ff42..69a5cb7 100644
--- a/cpu/arm926ejs/kirkwood/timer.c
+++ b/cpu/arm926ejs/kirkwood/timer.c
@@ -23,8 +23,10 @@
 
 #include <common.h>
 #include <asm/arch/kirkwood.h>
+#include <watchdog.h>
 
 #define UBOOT_CNTR	0	/* counter to use for uboot timer */
+#define WATCHDOG_TMR	2
 
 /* Timer reload and current value registers */
 struct kwtmr_val {
@@ -166,3 +168,39 @@ int timer_init(void)
 
 	return 0;
 }
+
+#if defined(CONFIG_HW_WATCHDOG)
+static unsigned long watchdog_timeout = 5;
+void hw_watchdog_reset(void)
+{
+	u32 time = CONFIG_SYS_TCLK * watchdog_timeout;
+
+	writel(time, CNTMR_VAL_REG(WATCHDOG_TMR));
+}
+
+#define MAX_TIMEOUT (0xffffffff / CONFIG_SYS_TCLK)
+int watchdog_enable(unsigned int timeout_secs)
+{
+	struct kwcpu_registers *cpureg =
+		(struct kwcpu_registers *)KW_CPU_REG_BASE;
+	u32 rstoutn_mask;
+	u32 cntmrctrl;
+
+	if (timeout_secs > MAX_TIMEOUT)
+		return -1;
+
+	watchdog_timeout = timeout_secs;
+	/* Enable CPU reset if watchdog expires */
+	rstoutn_mask = readl(cpureg->rstoutn_mask);
+	writel(rstoutn_mask |= 2, &cpureg->rstoutn_mask);
+	hw_watchdog_reset();
+
+	/* Enable the watchdog */
+	cntmrctrl = readl(CNTMR_CTRL_REG);
+	cntmrctrl |= CTCR_ARM_TIMER_EN(WATCHDOG_TMR);
+	cntmrctrl |= CTCR_ARM_TIMER_AUTO_EN(WATCHDOG_TMR);
+	writel(cntmrctrl, CNTMR_CTRL_REG);
+
+	return 0;
+}
+#endif
-- 
1.6.0.4