[U-Boot] [PATCH 06/11] arm: at91: Enable watchdog support

[Stefan Roese <sr@denx.de>]

This patch enables and starts the watchdog on the AT91 platform if
configured. Currently the WD timeout is configured to 16 seconds,
which is the longest value for this timer.

Signed-off-by: Stefan Roese <sr@denx.de>
Cc: Heiko Schocher <hs@denx.de>
Cc: Andreas Bießmann <andreas@biessmann.org>
Cc: Eugen Hristev <eugen.hristev@microchip.com>
---
 arch/arm/mach-at91/clock.c | 41 ++++++++++++++++++++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/arch/arm/mach-at91/clock.c b/arch/arm/mach-at91/clock.c
index 64cbc3d1ed..2d442d0092 100644
--- a/arch/arm/mach-at91/clock.c
+++ b/arch/arm/mach-at91/clock.c
@@ -5,6 +5,8 @@
  */
 
 #include <common.h>
+#include <dm.h>
+#include <wdt.h>
 #include <asm/io.h>
 #include <asm/arch/hardware.h>
 #include <asm/arch/at91_pmc.h>
@@ -118,3 +120,42 @@ void at91_pllicpr_init(u32 icpr)
 
 	writel(icpr, &pmc->pllicpr);
 }
+
+#if defined(CONFIG_WATCHDOG) && !defined(CONFIG_SPL_BUILD)
+static struct udevice *watchdog_dev;
+
+/* Called by macro WATCHDOG_RESET */
+void watchdog_reset(void)
+{
+	static ulong next_reset;
+	ulong now;
+
+	if (!watchdog_dev)
+		return;
+
+	now = get_timer(0);
+
+	/* Do not reset the watchdog too often */
+	if (now > next_reset) {
+		next_reset = now + 1000;	/* reset every 1000ms */
+		wdt_reset(watchdog_dev);
+	}
+}
+
+int arch_misc_init(void)
+{
+	/* Init watchdog */
+	if (uclass_get_device_by_seq(UCLASS_WDT, 0, &watchdog_dev)) {
+		debug("Watchdog: Not found by seq!\n");
+		if (uclass_get_device(UCLASS_WDT, 0, &watchdog_dev)) {
+			puts("Watchdog: Not found!\n");
+			return 0;
+		}
+	}
+
+	wdt_start(watchdog_dev, 16000, 0);	/* 16 seconds is max */
+	printf("Watchdog: Started\n");
+
+	return 0;
+}
+#endif
-- 
2.21.0