summaryrefslogtreecommitdiff
path: root/arch/arm/mach-omap1/reset.c
diff options
context:
space:
mode:
Diffstat (limited to 'arch/arm/mach-omap1/reset.c')
-rw-r--r--arch/arm/mach-omap1/reset.c63
1 files changed, 63 insertions, 0 deletions
diff --git a/arch/arm/mach-omap1/reset.c b/arch/arm/mach-omap1/reset.c
new file mode 100644
index 000000000..72bf4bf4a
--- /dev/null
+++ b/arch/arm/mach-omap1/reset.c
@@ -0,0 +1,63 @@
+/*
+ * OMAP1 reset support
+ */
+#include <linux/kernel.h>
+#include <linux/io.h>
+#include <linux/reboot.h>
+
+#include <mach/hardware.h>
+
+#include "iomap.h"
+#include "common.h"
+
+/* ARM_SYSST bit shifts related to SoC reset sources */
+#define ARM_SYSST_POR_SHIFT 5
+#define ARM_SYSST_EXT_RST_SHIFT 4
+#define ARM_SYSST_ARM_WDRST_SHIFT 2
+#define ARM_SYSST_GLOB_SWRST_SHIFT 1
+
+/* Standardized reset source bits (across all OMAP SoCs) */
+#define OMAP_GLOBAL_COLD_RST_SRC_ID_SHIFT 0
+#define OMAP_GLOBAL_WARM_RST_SRC_ID_SHIFT 1
+#define OMAP_MPU_WD_RST_SRC_ID_SHIFT 3
+#define OMAP_EXTWARM_RST_SRC_ID_SHIFT 5
+
+
+void omap1_restart(enum reboot_mode mode, const char *cmd)
+{
+ /*
+ * Workaround for 5912/1611b bug mentioned in sprz209d.pdf p. 28
+ * "Global Software Reset Affects Traffic Controller Frequency".
+ */
+ if (cpu_is_omap5912()) {
+ omap_writew(omap_readw(DPLL_CTL) & ~(1 << 4), DPLL_CTL);
+ omap_writew(0x8, ARM_RSTCT1);
+ }
+
+ omap_writew(1, ARM_RSTCT1);
+}
+
+/**
+ * omap1_get_reset_sources - return the source of the SoC's last reset
+ *
+ * Returns bits that represent the last reset source for the SoC. The
+ * format is standardized across OMAPs for use by the OMAP watchdog.
+ */
+u32 omap1_get_reset_sources(void)
+{
+ u32 ret = 0;
+ u16 rs;
+
+ rs = __raw_readw(OMAP1_IO_ADDRESS(ARM_SYSST));
+
+ if (rs & (1 << ARM_SYSST_POR_SHIFT))
+ ret |= 1 << OMAP_GLOBAL_COLD_RST_SRC_ID_SHIFT;
+ if (rs & (1 << ARM_SYSST_EXT_RST_SHIFT))
+ ret |= 1 << OMAP_EXTWARM_RST_SRC_ID_SHIFT;
+ if (rs & (1 << ARM_SYSST_ARM_WDRST_SHIFT))
+ ret |= 1 << OMAP_MPU_WD_RST_SRC_ID_SHIFT;
+ if (rs & (1 << ARM_SYSST_GLOB_SWRST_SHIFT))
+ ret |= 1 << OMAP_GLOBAL_WARM_RST_SRC_ID_SHIFT;
+
+ return ret;
+}