S5P: support generic watchdog timer

This patch adds support the generic watchdog timer for s5pc1xx and exynos4

Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Cc: HeungJun, Kim <riverful.kim@samsung.com>
diff --git a/arch/arm/cpu/armv7/s5p-common/wdt.c b/arch/arm/cpu/armv7/s5p-common/wdt.c
new file mode 100644
index 0000000..94acc1e
--- /dev/null
+++ b/arch/arm/cpu/armv7/s5p-common/wdt.c
@@ -0,0 +1,59 @@
+/*
+ * Copyright (C) 2012 Samsung Electronics
+ * Minkyu Kang <mk7.kang@samsung.com>
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.	 See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/watchdog.h>
+
+#define PRESCALER_VAL 255
+
+void wdt_stop(void)
+{
+	struct s5p_watchdog *wdt =
+		(struct s5p_watchdog *)samsung_get_base_watchdog();
+	unsigned int wtcon;
+
+	wtcon = readl(&wdt->wtcon);
+	wtcon &= ~(WTCON_EN | WTCON_INT | WTCON_RESET);
+
+	writel(wtcon, &wdt->wtcon);
+}
+
+void wdt_start(unsigned int timeout)
+{
+	struct s5p_watchdog *wdt =
+		(struct s5p_watchdog *)samsung_get_base_watchdog();
+	unsigned int wtcon;
+
+	wdt_stop();
+
+	wtcon = readl(&wdt->wtcon);
+	wtcon |= (WTCON_EN | WTCON_CLK(WTCON_CLK_128));
+	wtcon &= ~WTCON_INT;
+	wtcon |= WTCON_RESET;
+	wtcon |= WTCON_PRESCALER(PRESCALER_VAL);
+
+	writel(timeout, &wdt->wtdat);
+	writel(timeout, &wdt->wtcnt);
+	writel(wtcon, &wdt->wtcon);
+}