Re: [PATCH] clk: imx8mp: register driver at arch_initcall time

From: Ahmad Fatoum
Date: Mon Oct 24 2022 - 14:49:34 EST


Hello Rasmus,

On 24.10.22 15:48, Rasmus Villemoes wrote:
> On 28/09/2022 14.41, Rasmus Villemoes wrote:
>> We have an imx8mp-based board with an external gpio-triggered
>> watchdog. Currently, we don't get to handle that in time before it
>> resets the board.
>>
>> The probe of the watchdog device gets deferred because the SOC's GPIO
>> controller is not yet ready, and the probe of that in turn gets deferred
>> because its clock provider (namely, this driver) is not yet
>> ready. Altogether, the watchdog does not get handled until the late
>> initcall deferred_probe_initcall has made sure all leftover devices
>> have been probed, and that's way too late.
>>
>> Aside from being necessary for our board, this also reduces total boot
>> time because fewer device probes get deferred.
>
> ping

Module build is unaffected, because arch_initcall expands to module_init
if it's built as a module, right? Noting that in the commit message would
be good I think.

Also, did you try booting with fw_devlink=on? This should have resolved
your issue too. Not sure what other issues it may cause on i.MX8MP.

Cheers,
Ahmad

>
> Rasmus
>
>


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