[PATCH v2 2/3] watchdog: sama5d4: Fix setting timeout when watchdog is disabled

Guenter Roeck linux at roeck-us.net
Sun Feb 19 20:46:13 PST 2017


On 02/19/2017 03:52 PM, Alexandre Belloni wrote:
> On 19/02/2017 at 08:57:35 -0800, Guenter Roeck wrote:
>>>> That means if the watchdog is running, the timeout would not be updated.
>>>> It should be updated no matter if it is running or not.
>>>>
>>>
>>> No, it is enabling the watchdog, then changing WDV and WDD and finally
>>> disabling the watchdog if necessary. So, WDV and WDD are always changed.
>>>
>> You are correct. Sorry for the noise.
>>
>> Seems odd that the watchdog must be _running_ to change the timeout.
>> Usually, if there is a restriction, it is the opposite. I hope this
>> doesn't cause race conditions, where the watchdog fires immediately
>> after being enabled due to a low timeout.
>>
>
> While it is difficult to reproduce, I can confirm it races and sometimes
> reset the SoC without any good reason. It doesn't matter whether it is
> disabled or not
>

Outch :-(.

> I've raised the issue at Atmel last Thursday so I don't have any answer
> yet.
>

Please keep us in the loop.

Thanks,
Guenter





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