Nishanth (M),
Do you have an idea on that topic?
Signed-off-by: Charulatha V<charu@xxxxxx>
Reported-by: Kevin Hilman<khilman@xxxxxxxxxxxxxxxxxxx>
---
This patch is dependent on the below patch series (wdt hwmod) and
is created on top of pm-core branch.
http://www.spinics.net/lists/linux-omap/msg37043.html
arch/arm/mach-omap2/devices.c | 44 +++++++++++++++++++++++++++++++++++++++++
1 files changed, 44 insertions(+), 0 deletions(-)
diff --git a/arch/arm/mach-omap2/devices.c b/arch/arm/mach-omap2/devices.c
index 8e2f0aa..9f44fc6 100644
--- a/arch/arm/mach-omap2/devices.c
+++ b/arch/arm/mach-omap2/devices.c
@@ -916,11 +916,55 @@ static inline void omap_init_vout(void) {}
/*-------------------------------------------------------------------------*/
+/*
+ * WDT mdoule is reset during init which enables the watchdog.
typo: module
The real explanation is that you should not assume anything from the
boot loader at that time, so always stop the wdt.
+ * Hence it is required to disable the watchdog after the WDT reset
+ * during init. Otherwise the system would reboot as per the default
+ * watchdog timer registers settings.
+ */
+#define OMAP_WDT_WPS (0x34)
+#define OMAP_WDT_SPR (0x48)
+
+static int omap2_disable_wdt(struct omap_hwmod *oh, void *user)
You should call it unused if the parameter is not used.
+{
+ void __iomem *base;
+
+ if (!oh)
+ pr_err("Could not look up wdtimer_hwmod\n");
+
+ base = oh->_mpu_rt_va;
Paul added an hwmod API to get that va (something like *_get_mpu_rt_va).
+
+ /* Enable the clocks before accessing the WDT registers */
+ omap_hwmod_enable(oh);
The enable can fail, so you should check the return value.
+
+ /* sequence required to disable watchdog */
+ __raw_writel(0xAAAA, base + OMAP_WDT_SPR); /* TIMER_MODE */
+ while (__raw_readl(base + OMAP_WDT_WPS)& 0x10)
+ cpu_relax();
+
+ __raw_writel(0x5555, base + OMAP_WDT_SPR); /* TIMER_MODE */
+ while (__raw_readl(base + OMAP_WDT_WPS)& 0x10)
+ cpu_relax();
+
+ omap_hwmod_idle(oh);
+
+ return 0;
+}
+
+static void __init omap_disable_wdt(void)
+{
+ if (cpu_class_is_omap2())
This code is already in mach-omap2/devices.c, so that test should be
useless.
Regards,
Benoit
+ omap_hwmod_for_each_by_class("wd_timer",
+ omap2_disable_wdt, NULL);
+ return;
+}
+
static int __init omap2_init_devices(void)
{
/* please keep these calls, and their implementations above,
* in alphabetical order so they're easier to sort through.
*/
+ omap_disable_wdt();
omap_hsmmc_reset();
omap_init_camera();
omap_init_mbox();
