Message-ID: <eaf2ca0d-4d90-b68b-3b36-8bb0148cfb95@linaro.org>
Date:   Tue, 14 Mar 2023 12:36:18 +0100
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Subject: Re: [PATCH 3/3] arm64: dts: qcom: Split out SA8155P and use correct
 RPMh power domains
Content-Language: en-US
To:     Bjorn Andersson <andersson@kernel.org>
Cc:     linux-arm-msm@vger.kernel.org, agross@kernel.org,
        krzysztof.kozlowski@linaro.org, marijn.suijten@somainline.org,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        devicetree@vger.kernel.org, linux-kernel@vger.kernel.org
References: <20230214095435.2192153-1-konrad.dybcio@linaro.org>
 <20230214095435.2192153-3-konrad.dybcio@linaro.org>
 <20230314001052.7qvgbwkl73x22oll@ripper>
From:   Konrad Dybcio <konrad.dybcio@linaro.org>
In-Reply-To: <20230314001052.7qvgbwkl73x22oll@ripper>
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Precedence: bulk


On 14.03.2023 01:10, Bjorn Andersson wrote:
> On Tue, Feb 14, 2023 at 10:54:35AM +0100, Konrad Dybcio wrote:
>> The RPMhPD setup on SA8155P is different compared to SM8150. Correct
>> it to ensure the platform will not try accessing forbidden/missing
>> RPMh entries at boot, as a bad vote will hang the machine.
>>
> 
> I don't see that this will scale, as soon as someone adds a new device
> in sm8150.dtsi that has the need to scale a power rail this will be
> forgotten and we will have a mix of references to the SM8150 and SA8155P
> value space.
> 
> That said, I think it's reasonable to avoid duplicating the entire
> sm8150.dtsi.
Yeah, this problem has no obvious good solutions and even though it's
not very elegant, this seems to be the less bad one..

> 
> How about making the SA8155P_* macros match the SM8150_* macros?
> That way things will fail gracefully if a device node references a
> resource not defined for either platform...
Okay, let's do that

Konrad
> 
> Regards,
> Bjorn
> 
>> Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
>> ---
>>  arch/arm64/boot/dts/qcom/sa8155p-adp.dts |  2 +-
>>  arch/arm64/boot/dts/qcom/sa8155p.dtsi    | 51 ++++++++++++++++++++++++
>>  2 files changed, 52 insertions(+), 1 deletion(-)
>>  create mode 100644 arch/arm64/boot/dts/qcom/sa8155p.dtsi
>>
>> diff --git a/arch/arm64/boot/dts/qcom/sa8155p-adp.dts b/arch/arm64/boot/dts/qcom/sa8155p-adp.dts
>> index 459384ec8f23..9454e8e4e517 100644
>> --- a/arch/arm64/boot/dts/qcom/sa8155p-adp.dts
>> +++ b/arch/arm64/boot/dts/qcom/sa8155p-adp.dts
>> @@ -7,7 +7,7 @@
>>  
>>  #include <dt-bindings/regulator/qcom,rpmh-regulator.h>
>>  #include <dt-bindings/gpio/gpio.h>
>> -#include "sm8150.dtsi"
>> +#include "sa8155p.dtsi"
>>  #include "pmm8155au_1.dtsi"
>>  #include "pmm8155au_2.dtsi"
>>  
>> diff --git a/arch/arm64/boot/dts/qcom/sa8155p.dtsi b/arch/arm64/boot/dts/qcom/sa8155p.dtsi
>> new file mode 100644
>> index 000000000000..f2fd7c28764e
>> --- /dev/null
>> +++ b/arch/arm64/boot/dts/qcom/sa8155p.dtsi
>> @@ -0,0 +1,51 @@
>> +// SPDX-License-Identifier: BSD-3-Clause
>> +/*
>> + * Copyright (c) 2023, Linaro Limited
>> + *
>> + * SA8155P is an automotive variant of SM8150, with some minor changes.
>> + * Most notably, the RPMhPD setup differs: MMCX and LCX/LMX rails are gone.
>> + */
>> +
>> +#include "sm8150.dtsi"
>> +
>> +&dispcc {
>> +	power-domains = <&rpmhpd SA8155P_CX>;
>> +};
>> +
>> +&mdss_mdp {
>> +	power-domains = <&rpmhpd SA8155P_CX>;
>> +};
>> +
>> +&mdss_dsi0 {
>> +	power-domains = <&rpmhpd SA8155P_CX>;
>> +};
>> +
>> +&mdss_dsi1 {
>> +	power-domains = <&rpmhpd SA8155P_CX>;
>> +};
>> +
>> +&remoteproc_adsp {
>> +	power-domains = <&rpmhpd SA8155P_CX>;
>> +};
>> +
>> +&remoteproc_cdsp {
>> +	power-domains = <&rpmhpd SA8155P_CX>;
>> +};
>> +
>> +&remoteproc_mpss {
>> +	power-domains = <&rpmhpd SA8155P_CX>,
>> +			<&rpmhpd SA8155P_MSS>;
>> +};
>> +
>> +&remoteproc_slpi {
>> +	power-domains = <&rpmhpd SA8155P_CX>,
>> +			<&rpmhpd SA8155P_MX>;
>> +};
>> +
>> +&rpmhpd {
>> +	compatible = "qcom,sa8155p-rpmhpd";
>> +};
>> +
>> +&sdhc_2 {
>> +	power-domains = <&rpmhpd SA8155P_CX>;
>> +};
>> -- 
>> 2.39.1
>>