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-rw-r--r--arch/arm/mach-omap2/wd_timer.c45
1 files changed, 45 insertions, 0 deletions
diff --git a/arch/arm/mach-omap2/wd_timer.c b/arch/arm/mach-omap2/wd_timer.c
index 4067669..b2f1c67 100644
--- a/arch/arm/mach-omap2/wd_timer.c
+++ b/arch/arm/mach-omap2/wd_timer.c
@@ -14,6 +14,7 @@
#include <plat/omap_hwmod.h>
#include "wd_timer.h"
+#include "common.h"
/*
* In order to avoid any assumptions from bootloader regarding WDT
@@ -25,6 +26,8 @@
#define OMAP_WDT_WPS 0x34
#define OMAP_WDT_SPR 0x48
+/* Maximum microseconds to wait for OMAP module to softreset */
+#define MAX_MODULE_SOFTRESET_WAIT 10000
int omap2_wd_timer_disable(struct omap_hwmod *oh)
{
@@ -54,3 +57,45 @@ int omap2_wd_timer_disable(struct omap_hwmod *oh)
return 0;
}
+/**
+ * omap2_wdtimer_reset - reset and disable the WDTIMER IP block
+ * @oh: struct omap_hwmod *
+ *
+ * After the WDTIMER IP blocks are reset on OMAP2/3, we must also take
+ * care to execute the special watchdog disable sequence. This is
+ * because the watchdog is re-armed upon OCP softreset. (On OMAP4,
+ * this behavior was apparently changed and the watchdog is no longer
+ * re-armed after an OCP soft-reset.) Returns -ETIMEDOUT if the reset
+ * did not complete, or 0 upon success.
+ *
+ * XXX Most of this code should be moved to the omap_hwmod.c layer
+ * during a normal merge window. omap_hwmod_softreset() should be
+ * renamed to omap_hwmod_set_ocp_softreset(), and omap_hwmod_softreset()
+ * should call the hwmod _ocp_softreset() code.
+ */
+int omap2_wd_timer_reset(struct omap_hwmod *oh)
+{
+ int c = 0;
+
+ /* Write to the SOFTRESET bit */
+ omap_hwmod_softreset(oh);
+
+ /* Poll on RESETDONE bit */
+ omap_test_timeout((omap_hwmod_read(oh,
+ oh->class->sysc->syss_offs)
+ & SYSS_RESETDONE_MASK),
+ MAX_MODULE_SOFTRESET_WAIT, c);
+
+ if (oh->class->sysc->srst_udelay)
+ udelay(oh->class->sysc->srst_udelay);
+
+ if (c == MAX_MODULE_SOFTRESET_WAIT)
+ pr_warning("%s: %s: softreset failed (waited %d usec)\n",
+ __func__, oh->name, MAX_MODULE_SOFTRESET_WAIT);
+ else
+ pr_debug("%s: %s: softreset in %d usec\n", __func__,
+ oh->name, c);
+
+ return (c == MAX_MODULE_SOFTRESET_WAIT) ? -ETIMEDOUT :
+ omap2_wd_timer_disable(oh);
+}