Subject: [PATCH 1/1] Watchdog: OMAP3: fix wrong boot status from wdt reboot

From: [email-masked] (Shubhrajyoti)
Date: Thu, 05 Jul 2012 11:09:31 +0530

Hello,
On Wednesday 04 July 2012 09:27 PM, zumeng.chen wrote:
> To: Shubhrajyoti
> On 2012?07?04? 23:54, Zumeng Chen wrote:
>> Does the following fix make sense?
yes , thanks for the patch.
IIRC Rajendra had a similar one.
Some comments below.
>>
>> WDIOC_GETBOOTSTATUS always return 0 even if the machine
>> comes from omap-wdt reboot. Because WKUP_MOD is not right
>> for OMAP3,so give the right addr 0xA00 of PRM_RSTST for
>> get_reset_sources, which inputs the signal from omap-wdt
>> reboot, and return 1 when coming from omap-wdt reboot for
>> WDIOC_GETBOOTSTATUS.
>>
>> Signed-off-by: Zumeng Chen<[email-masked]>
>> ---
>>   arch/arm/mach-omap2/prcm.c  |    4 +++-
>>   drivers/watchdog/omap_wdt.c |    3 +++
>>   drivers/watchdog/omap_wdt.h |    3 +++
>>   3 files changed, 9 insertions(+), 1 deletions(-)
>>
>> diff --git a/arch/arm/mach-omap2/prcm.c b/arch/arm/mach-omap2/prcm.c
>> index 480f40a..43f3feb 100644
>> --- a/arch/arm/mach-omap2/prcm.c
>> +++ b/arch/arm/mach-omap2/prcm.c
>> @@ -49,8 +49,10 @@ void __iomem *prcm_mpu_base;
>>   u32 omap_prcm_get_reset_sources(void)
>>   {
>>       /* XXX This presumably needs modification for 34XX */
>> -    if (cpu_is_omap24xx() || cpu_is_omap34xx())
>> +    if (cpu_is_omap24xx())
>>           return omap2_prm_read_mod_reg(WKUP_MOD, OMAP2_RM_RSTST)& 
>> 0x7f;
>> +    if (cpu_is_omap34xx())
>> +        return omap2_prm_read_mod_reg(0xA00, OMAP2_RM_RSTST)&  0x7f;
>>       if (cpu_is_omap44xx())
>>           return omap2_prm_read_mod_reg(WKUP_MOD, OMAP4_RM_RSTST)& 
>> 0x7f;
>>
>> diff --git a/drivers/watchdog/omap_wdt.c b/drivers/watchdog/omap_wdt.c
>> index 8285d65..ea57078 100644
>> --- a/drivers/watchdog/omap_wdt.c
>> +++ b/drivers/watchdog/omap_wdt.c
>> @@ -234,6 +234,9 @@ static long omap_wdt_ioctl(struct file *file,
>> unsigned int cmd,
>>           if (cpu_is_omap24xx())
>>               return put_user(omap_prcm_get_reset_sources(),
>>                       (int __user *)arg);
>> +        if (cpu_is_omap34xx())
>> +            return put_user(omap_prcm_get_reset_sources()&  0x10>>
>> +                OMAP3_PRM_RSTST_BIT, (int __user *)arg);
Actually instead of returning yes/no.
The correct  expectation is to return WDIOF_* flags as defined in
include/linux/watchdog.h.

(BTW I agree that was something even current code is not
following).Since you are at it may be that?s
something you can consider.

>>           return put_user(0, (int __user *)arg);
>>       case WDIOC_KEEPALIVE:
>>           pm_runtime_get_sync(wdev->dev);
>> diff --git a/drivers/watchdog/omap_wdt.h b/drivers/watchdog/omap_wdt.h
>> index 09b774c..d8d5daa 100644
>> --- a/drivers/watchdog/omap_wdt.h
>> +++ b/drivers/watchdog/omap_wdt.h
>> @@ -40,6 +40,9 @@
>>   #define OMAP_WATCHDOG_WPS        (0x34)
>>   #define OMAP_WATCHDOG_SPR        (0x48)
>>
>> +/* PRM_RSTST MPU_WD_RST bit */
>> +#define OMAP3_PRM_RSTST_BIT        4
>> +
>>   /* Using the prescaler, the OMAP watchdog could go for many
>>    * months before firing.  These limits work without scaling,
>>    * with the 60 second default assumed by most tools and docs.
>