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Message-ID: <e87ac9f3-e0ce-bd4c-6e2c-d57adb0c9169@linaro.org>
Date:   Tue, 13 Dec 2022 17:31:40 +0100
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Subject: Re: [PATCH v2 11/13] arm64: dts: qcom: sm6350: Remove reg-names
 property from LLCC node
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To:     Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>,
        andersson@kernel.org, robh+dt@kernel.org,
        krzysztof.kozlowski+dt@linaro.org, bp@alien8.de,
        tony.luck@intel.com
Cc:     quic_saipraka@quicinc.com, konrad.dybcio@linaro.org,
        linux-arm-msm@vger.kernel.org, linux-kernel@vger.kernel.org,
        james.morse@arm.com, mchehab@kernel.org, rric@kernel.org,
        linux-edac@vger.kernel.org, quic_ppareek@quicinc.com,
        luca.weiss@fairphone.com, stable@vger.kernel.org
References: <20221212123311.146261-1-manivannan.sadhasivam@linaro.org>
 <20221212123311.146261-12-manivannan.sadhasivam@linaro.org>
From:   Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
In-Reply-To: <20221212123311.146261-12-manivannan.sadhasivam@linaro.org>
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On 12/12/2022 13:33, Manivannan Sadhasivam wrote:
> The LLCC block has several banks each with a different base address
> and holes in between. So it is not a correct approach to cover these
> banks with a single offset/size. Instead, the individual bank's base
> address needs to be specified in devicetree with the exact size.
> 
> On SM6350, there is only one LLCC bank available. So only change needed is
> to remove the reg-names property from LLCC node to conform to the binding.
> 
> The driver is expected to parse the reg field based on index to get the
> addresses of each LLCC banks.
> 
> Cc: <stable@vger.kernel.org> # 5.16
> Fixes: ced2f0d75e13 ("arm64: dts: qcom: sm6350: Add LLCC node")

This is a definitive no go. There is no bug here and such change cannot
be backported.

> Reported-by: Parikshit Pareek <quic_ppareek@quicinc.com>

What is the bug here which deserves a credit? reg-names in v5.16 were
perfectly correct.

> Signed-off-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
> ---
>  arch/arm64/boot/dts/qcom/sm6350.dtsi | 1 -
>  1 file changed, 1 deletion(-)
> 
> diff --git a/arch/arm64/boot/dts/qcom/sm6350.dtsi b/arch/arm64/boot/dts/qcom/sm6350.dtsi
> index 43324bf291c3..1f39627cd7c6 100644
> --- a/arch/arm64/boot/dts/qcom/sm6350.dtsi
> +++ b/arch/arm64/boot/dts/qcom/sm6350.dtsi
> @@ -1174,7 +1174,6 @@ dc_noc: interconnect@9160000 {
>  		system-cache-controller@9200000 {
>  			compatible = "qcom,sm6350-llcc";
>  			reg = <0 0x09200000 0 0x50000>, <0 0x09600000 0 0x50000>;
> -			reg-names = "llcc_base", "llcc_broadcast_base";
>  		};
>  
>  		gem_noc: interconnect@9680000 {

Best regards,
Krzysztof