Re: [PATCH v2 0/6] Switch to generic syscon regmap based drivers

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Hi Javier,

On Wed, Oct 21, 2015 at 6:53 PM, Javier Martinez Canillas
<javier@xxxxxxxxxxxxxxx> wrote:
> Hello Alim,
>
> On 10/21/2015 12:44 PM, Alim Akhtar wrote:
>
> [snip]
>
>>>
>>> Can you please test following patch [0] on top of Alim's series? If that
>>> works then it should either be part of Alim's series or the patches will
>>> have to wait until that patch lands into mainline. I don't have an eMMC
>>> to test it in XU4 but I'm pretty confident that it will solve the issue.
>>>
>> I am fine with including this with my series or lowering syscon_restart_handler priority to 128.
>
> Yes, I also considered changing the syscon-reboot handler priority to 128 but
> then I noticed this commit:
>
> b81180b3fd48 ("power: reset: adjust priority of simple syscon reboot driver").
>
> So as you can see, it was 128 before but was bumped to 192 so it was called
> before restart handlers registered by watchdogs. So, changing to 128 would
> break other people use cases.
>
> Now, I don't know if that is the right fix since register_restart_handler()
> explanation about the policy used for restart handler priority numbers is
> scarce. It only mentions 0, 128 and 255 so probably the correct thing to do
> is to change all watchdog restart handler to 0 but that is a separate issue.
>
>> It also make sense to increase eMMC priority as you suggested as before system reboot, devices should have reseted itself.
>
> That was my rationale as well and is why I think the handler for devices
> should use the highest priority regardless if the syscon-reboot is later
> changed to prio 128 and the watchdog handlers to 0.
>
I agree, in any case dumping up eMMC reset priority make sense.
If all is good here, over to Krzysztof and Ulf to handle these patches.
Thanks.
> Best regards,
>
> [0]: http://lxr.free-electrons.com/source/kernel/reboot.c#L113
>
> Best regards,
> --
> Javier Martinez Canillas
> Open Source Group
> Samsung Research America



-- 
Regards,
Alim
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