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Message-ID: <05d6f9e6-a291-35c3-9b02-2235ad92669d@gmail.com>
Date:   Fri, 16 Dec 2022 14:17:54 +0100
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Subject: Re: [PATCH resend] arm64: dts: mediatek: mt8192: Mark scp_adsp clock
 as broken
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To:     AngeloGioacchino Del Regno 
        <angelogioacchino.delregno@collabora.com>,
        Chen-Yu Tsai <wenst@chromium.org>
Cc:     Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        =?UTF-8?Q?N=c3=adcolas_F_=2e_R_=2e_A_=2e_Prado?= 
        <nfraprado@collabora.com>, devicetree@vger.kernel.org,
        linux-arm-kernel@lists.infradead.org,
        linux-mediatek@lists.infradead.org, linux-kernel@vger.kernel.org,
        "allen-kh.cheng" <allen-kh.cheng@mediatek.com>
References: <20221130031741.3176853-1-wenst@chromium.org>
 <2ec80bd8-dfef-d2e6-eb41-6e6088043e33@collabora.com>
 <CAGXv+5E=X_hwg76=B_jqWrpieo8bR-=r8NLbNz2=JzE=kBwMWQ@mail.gmail.com>
 <8806f4cf-2141-acb8-1f9d-cd6ade64756e@collabora.com>
From:   Matthias Brugger <matthias.bgg@gmail.com>
In-Reply-To: <8806f4cf-2141-acb8-1f9d-cd6ade64756e@collabora.com>
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On 01/12/2022 10:02, AngeloGioacchino Del Regno wrote:
> Il 01/12/22 09:56, Chen-Yu Tsai ha scritto:
>> On Wed, Nov 30, 2022 at 7:10 PM AngeloGioacchino Del Regno
>> <angelogioacchino.delregno@collabora.com> wrote:
>>>
>>> Il 30/11/22 04:17, Chen-Yu Tsai ha scritto:
>>>> The scp_adsp clock controller is under the SCP_ADSP power domain. This
>>>> power domain is currently not supported nor defined.
>>>>
>>>> Mark the clock controller as broken for now, to avoid the system from
>>>> trying to access it, and causing the CPU or bus to stall.
>>>>
>>>> Fixes: 5d2b897bc6f5 ("arm64: dts: mediatek: Add mt8192 clock controllers")
>>>> Signed-off-by: Chen-Yu Tsai <wenst@chromium.org>
>>>
>>> ....or we can add the ADSP power domain to actually fix this properly, which 
>>> looks
>>> like being a generally good idea :-)
>>
>> Sure, but that and any driver changes have to be backported, or anything
>> touching the clocks will still break the system.
>>
> 
> I agree.
> 
>> There's no reason we can't have both. I think having this one merged and
>> backported to stable first, then adding the SCP_ADSP power domain, and tying
>> it to the clock controller as a follow up addition works best.
>>
>> What do you think?
>>
> 
> I think that one reason to not have both is that we'd have to revert this commit
> after the SCP_ADSP power domain is added (with the appropriate Fixes tags and/or
> Cc stable)...
> 
> I'd expect that entire addition to be no more than 3 commits, including the dtsi
> one... and if it comes out as I expect, we'd be solving that issue on all of the
> affected older versions of the kernel - the right way.
> 
> Can we wait for... let's say, a day or two to check how that works, before taking
> a final decision on this commit?
> 

Do I understand correctly that the correct way for now is to merge this patch 
until we have a fixed the power domain controller?

Regards,
Matthias