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Date:   Wed, 19 Apr 2023 13:05:26 -0700
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Subject: Re: [Freedreno] [PATCH 1/5] dt-bindings: display/msm: Add reg bus
 interconnect
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To:     Konrad Dybcio <konrad.dybcio@linaro.org>,
        Rob Clark <robdclark@gmail.com>,
        Abhinav Kumar <quic_abhinavk@quicinc.com>,
        Dmitry Baryshkov <dmitry.baryshkov@linaro.org>,
        Sean Paul <sean@poorly.run>, David Airlie <airlied@gmail.com>,
        Daniel Vetter <daniel@ffwll.ch>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Krishna Manikandan <quic_mkrishn@quicinc.com>
CC:     <devicetree@vger.kernel.org>, <linux-arm-msm@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <dri-devel@lists.freedesktop.org>,
        "Marijn Suijten" <marijn.suijten@somainline.org>,
        <freedreno@lists.freedesktop.org>
References: <20230417-topic-dpu_regbus-v1-0-06fbdc1643c0@linaro.org>
 <20230417-topic-dpu_regbus-v1-1-06fbdc1643c0@linaro.org>
From:   Jeykumar Sankaran <quic_jeykumar@quicinc.com>
In-Reply-To: <20230417-topic-dpu_regbus-v1-1-06fbdc1643c0@linaro.org>
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Resending the question as the previous one was sent only to the 
freedreno list. Apologies for spamming!

On 4/17/2023 8:30 AM, Konrad Dybcio wrote:
> Apart from the already handled data bus (MAS_MDP_Pn<->DDR), there's
> another path that needs to be handled to ensure MDSS functions properly,
> namely the "reg bus", a.k.a the CPU-MDSS interconnect.
> 
> Gating that path may have a variety of effects.. from none to otherwise
> inexplicable DSI timeouts..
> 
> Describe it in bindings to allow for use in device trees.
> 
> Signed-off-by: Konrad Dybcio <konrad.dybcio@linaro.org>
> ---
>   Documentation/devicetree/bindings/display/msm/mdss-common.yaml | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/Documentation/devicetree/bindings/display/msm/mdss-common.yaml b/Documentation/devicetree/bindings/display/msm/mdss-common.yaml
> index ccd7d6417523..9eb5b6d3e0b9 100644
> --- a/Documentation/devicetree/bindings/display/msm/mdss-common.yaml
> +++ b/Documentation/devicetree/bindings/display/msm/mdss-common.yaml
> @@ -72,6 +72,7 @@ properties:
>       items:
>         - const: mdp0-mem
>         - const: mdp1-mem
> +      - const: cpu-cfg
>   
If posted already, please point to the DTSI patch for this ICC path.
>     resets:
>       items:
>