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Message-ID: <ed50cdff-8fd2-6714-9b0b-1ce47a5c9d37@pengutronix.de>
Date:   Mon, 24 Oct 2022 16:00:01 +0200
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Subject: Re: [PATCH] clk: imx8mp: register driver at arch_initcall time
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To:     Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        Abel Vesa <abelvesa@kernel.org>,
        Michael Turquette <mturquette@baylibre.com>,
        Stephen Boyd <sboyd@kernel.org>,
        Shawn Guo <shawnguo@kernel.org>,
        Sascha Hauer <s.hauer@pengutronix.de>,
        Pengutronix Kernel Team <kernel@pengutronix.de>,
        Fabio Estevam <festevam@gmail.com>,
        NXP Linux Team <linux-imx@nxp.com>
Cc:     linux-kernel@vger.kernel.org, linux-clk@vger.kernel.org
References: <20220928124108.500369-1-linux@rasmusvillemoes.dk>
 <814496ae-4007-9a4e-0466-a0386aec6316@rasmusvillemoes.dk>
From:   Ahmad Fatoum <a.fatoum@pengutronix.de>
In-Reply-To: <814496ae-4007-9a4e-0466-a0386aec6316@rasmusvillemoes.dk>
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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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