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Message-ID: <c4cc7365-df3e-f591-58b8-b844d5bf1737@linaro.org>
Date:   Thu, 29 Dec 2022 12:04:00 +0100
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Subject: Re: [PATCH v2 1/7] arm64: dts: qcom: sm8450: add spmi node
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To:     Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>,
        linux-arm-msm@vger.kernel.org, andersson@kernel.org,
        agross@kernel.org
Cc:     marijn.suijten@somainline.org, Vinod Koul <vkoul@kernel.org>,
        Konrad Dybcio <konrad.dybcio@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: <20221229103212.984324-1-konrad.dybcio@linaro.org>
 <7b32e414-96a9-7265-efee-f872badb32b2@linaro.org>
 <71d7a162-569d-1443-9e53-3ba374d06ccd@linaro.org>
 <ee24809b-cf9b-c555-9c30-956949be25a4@linaro.org>
From:   Konrad Dybcio <konrad.dybcio@linaro.org>
In-Reply-To: <ee24809b-cf9b-c555-9c30-956949be25a4@linaro.org>
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On 29.12.2022 11:57, Krzysztof Kozlowski wrote:
> On 29/12/2022 11:45, Konrad Dybcio wrote:
>>
>>
>> On 29.12.2022 11:42, Krzysztof Kozlowski wrote:
>>> On 29/12/2022 11:32, Konrad Dybcio wrote:
>>>> From: Vinod Koul <vkoul@kernel.org>
>>>>
>>>> Add the spmi bus as found in the SM8450 SoC
>>>>
>>>> Signed-off-by: Vinod Koul <vkoul@kernel.org>
>>>> Reviewed-by: Konrad Dybcio <konrad.dybcio@somainline.org>
>>>> [Konrad: 0x0 -> 0, move #cells down, make reg-names a vertical list]
>>>> Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
>>>> ---
>>>> v1 -> v2:
>>>> No changes
>>>>
>>>>  arch/arm64/boot/dts/qcom/sm8450.dtsi | 22 ++++++++++++++++++++++
>>>>  1 file changed, 22 insertions(+)
>>>>
>>>> diff --git a/arch/arm64/boot/dts/qcom/sm8450.dtsi b/arch/arm64/boot/dts/qcom/sm8450.dtsi
>>>> index 570475040d95..b9b59c5223eb 100644
>>>> --- a/arch/arm64/boot/dts/qcom/sm8450.dtsi
>>>> +++ b/arch/arm64/boot/dts/qcom/sm8450.dtsi
>>>> @@ -2715,6 +2715,28 @@ aoss_qmp: power-controller@c300000 {
>>>>  			#clock-cells = <0>;
>>>>  		};
>>>>  
>>>> +		spmi_bus: spmi@c42d000 {
>>>
>>> Hmm looks different than reg.
>>>
>>>> +			compatible = "qcom,spmi-pmic-arb";
>>>> +			reg = <0 0x0c400000 0 0x00003000>,
>>>> +			      <0 0x0c500000 0 0x00400000>,
>>>> +			      <0 0x0c440000 0 0x00080000>,
>>>> +			      <0 0x0c4c0000 0 0x00010000>,
>>>> +			      <0 0x0c42d000 0 0x00010000>;
>>> x
>> Hm, my guess would be that Vinod chose to put the "cnfg" reg
>> instead of "core" in the unit address, as 8450 has 2 SPMI bus
>> hosts and they both share the core reg, so it would have been
>> impossible to have two spmi@core nodes..
> 
> Eh? SM8450 has 2 SPMI hosts both using 0x0c400000? How does that work?
> Usually address can be mapped only once.
No idea either!

> 
> Where is the second SPMI? I cannot find it in linux-next.
It's only there on downstream and I'm not sure how useful it is
really, only some debug subdevice is attached to it.. Perhaps
we could ignore its existence for now and I could use the core
reg in unit address for spmi0?

Konrad
> 
> 
> Best regards,
> Krzysztof
>