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Date:   Mon, 2 Jan 2023 09:43:26 +0100
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Subject: Re: [PATCH 1/7] arm64: dts: qcom: sc8280xp: remove GCC from CX power
 domain
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To:     Konrad Dybcio <konrad.dybcio@linaro.org>,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
References: <20221230160103.250996-1-krzysztof.kozlowski@linaro.org>
 <9bfe5409-3174-c3be-b0b9-55c5a857e834@linaro.org>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <9bfe5409-3174-c3be-b0b9-55c5a857e834@linaro.org>
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On 31/12/2022 00:41, Konrad Dybcio wrote:
> 
> 
> On 30.12.2022 17:00, Krzysztof Kozlowski wrote:
>> Bindings do not allow power-domain property in GCC clock controller and
>> documentation does not indicate that GCC is part of VDD_CX.
>>
>> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
>>
>> ---
>>
>> Maybe the bindings should be fixed? Maybe this was added as workaround?
>> Anyway looking at documentation I do not see such relation, except
>> downstream vdd_cx-supply (which is the same as in other SoCs and we do
>> not represent it in upstream).
> Some clocks scale with _CX, which is annotated on downstream with vdd-levels.
> We take care of that by using opp tables in consumer drivers. Usually if
> power-domains is added to a clock controller, it means that at least one of
> the clocks needs the power domain to be on (which.. should be true for CX
> if the ARM part runs anyway, no?), as for example VDD_MX/VDD_GFX may not be
> on at boot and trying to enable such clocks would result in a big kaboom..
> 
> TL;DR: if nothing exploded, it's fine to remove it

According to Bjorn, we should keep the domain.

Best regards,
Krzysztof