[1/5] dt-bindings: display/msm: Add reg bus interconnect

Message ID 20230417-topic-dpu_regbus-v1-1-06fbdc1643c0@linaro.org
State New
Headers
Series MDSS reg bus interconnect |

Commit Message

Konrad Dybcio April 17, 2023, 3:30 p.m. UTC
  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(+)
  

Comments

Krzysztof Kozlowski April 18, 2023, 7:24 a.m. UTC | #1
On 17/04/2023 17:30, 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

You added only interconnect-name, not actual interconnect.

Best regards,
Krzysztof
  
Jeykumar Sankaran April 19, 2023, 8:05 p.m. UTC | #2
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:
>
  
Dmitry Baryshkov April 20, 2023, 12:26 a.m. UTC | #3
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:
>>
  

Patch

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
 
   resets:
     items: