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Date:   Thu, 20 Apr 2023 03:26:04 +0300
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Subject: Re: [Freedreno] [PATCH 1/5] dt-bindings: display/msm: Add reg bus
 interconnect
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To:     Jeykumar Sankaran <quic_jeykumar@quicinc.com>,
        Konrad Dybcio <konrad.dybcio@linaro.org>,
        Rob Clark <robdclark@gmail.com>,
        Abhinav Kumar <quic_abhinavk@quicinc.com>,
        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>
 <c20433cb-02e4-bd82-99ab-bd25a49771d4@quicinc.com>
From:   Dmitry Baryshkov <dmitry.baryshkov@linaro.org>
In-Reply-To: <c20433cb-02e4-bd82-99ab-bd25a49771d4@quicinc.com>
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On 19/04/2023 23:05, Jeykumar Sankaran wrote:
> 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.

Probably it's worth updating the example in one of mdss schemas.

>>     resets:
>>       items:
>>

-- 
With best wishes
Dmitry