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-rw-r--r--arch/arm/mach-davinci/time.c95
1 files changed, 95 insertions, 0 deletions
diff --git a/arch/arm/mach-davinci/time.c b/arch/arm/mach-davinci/time.c
new file mode 100644
index 0000000000..1e0071957e
--- /dev/null
+++ b/arch/arm/mach-davinci/time.c
@@ -0,0 +1,95 @@
+/*
+ * DaVinci timer subsystem
+ *
+ * Author: Kevin Hilman, MontaVista Software, Inc. <source@mvista.com>
+ *
+ * 2007 (c) MontaVista Software, Inc. This file is licensed under
+ * the terms of the GNU General Public License version 2. This program
+ * is licensed "as is" without any warranty of any kind, whether express
+ * or implied.
+ */
+
+#include <common.h>
+#include <io.h>
+
+#include <mach/time.h>
+
+/* Timer register offsets */
+#define PID12 0x0
+#define TIM12 0x10
+#define TIM34 0x14
+#define PRD12 0x18
+#define PRD34 0x1c
+#define TCR 0x20
+#define TGCR 0x24
+#define WDTCR 0x28
+
+/* Timer register bitfields */
+#define TCR_ENAMODE_DISABLE 0x0
+#define TCR_ENAMODE_ONESHOT 0x1
+#define TCR_ENAMODE_PERIODIC 0x2
+#define TCR_ENAMODE_MASK 0x3
+
+#define TGCR_TIMMODE_SHIFT 2
+#define TGCR_TIMMODE_64BIT_GP 0x0
+#define TGCR_TIMMODE_32BIT_UNCHAINED 0x1
+#define TGCR_TIMMODE_64BIT_WDOG 0x2
+#define TGCR_TIMMODE_32BIT_CHAINED 0x3
+
+#define TGCR_TIM12RS_SHIFT 0
+#define TGCR_TIM34RS_SHIFT 1
+#define TGCR_RESET 0x0
+#define TGCR_UNRESET 0x1
+#define TGCR_RESET_MASK 0x3
+
+#define WDTCR_WDEN_SHIFT 14
+#define WDTCR_WDEN_DISABLE 0x0
+#define WDTCR_WDEN_ENABLE 0x1
+#define WDTCR_WDKEY_SHIFT 16
+#define WDTCR_WDKEY_SEQ0 0xa5c6
+#define WDTCR_WDKEY_SEQ1 0xda7e
+
+/* reset board using watchdog timer */
+void __noreturn reset_cpu(ulong addr)
+{
+ u32 tgcr, wdtcr;
+ void __iomem *base;
+
+ base = IOMEM(DAVINCI_WDOG_BASE);
+
+ /* disable, internal clock source */
+ __raw_writel(0, base + TCR);
+
+ /* reset timer, set mode to 64-bit watchdog, and unreset */
+ tgcr = 0;
+ __raw_writel(tgcr, base + TGCR);
+ tgcr = TGCR_TIMMODE_64BIT_WDOG << TGCR_TIMMODE_SHIFT;
+ tgcr |= (TGCR_UNRESET << TGCR_TIM12RS_SHIFT) |
+ (TGCR_UNRESET << TGCR_TIM34RS_SHIFT);
+ __raw_writel(tgcr, base + TGCR);
+
+ /* clear counter and period regs */
+ __raw_writel(0, base + TIM12);
+ __raw_writel(0, base + TIM34);
+ __raw_writel(0, base + PRD12);
+ __raw_writel(0, base + PRD34);
+
+ /* put watchdog in pre-active state */
+ wdtcr = __raw_readl(base + WDTCR);
+ wdtcr = (WDTCR_WDKEY_SEQ0 << WDTCR_WDKEY_SHIFT) |
+ (WDTCR_WDEN_ENABLE << WDTCR_WDEN_SHIFT);
+ __raw_writel(wdtcr, base + WDTCR);
+
+ /* put watchdog in active state */
+ wdtcr = (WDTCR_WDKEY_SEQ1 << WDTCR_WDKEY_SHIFT) |
+ (WDTCR_WDEN_ENABLE << WDTCR_WDEN_SHIFT);
+ __raw_writel(wdtcr, base + WDTCR);
+
+ /* write an invalid value to the WDKEY field to trigger
+ * a watchdog reset */
+ wdtcr = 0x00004000;
+ __raw_writel(wdtcr, base + WDTCR);
+
+ unreachable();
+}
+EXPORT_SYMBOL(reset_cpu);