Re: [PATCH V5 1/4] dt-bindings: interconnect: Add EPSS L3 compatible for SA8775P
From: Krzysztof Kozlowski
Date: Thu Nov 21 2024 - 12:51:57 EST
On 21/11/2024 18:43, Raviteja Laggyshetty wrote:
>
>
> On 11/21/2024 5:23 PM, Krzysztof Kozlowski wrote:
>> On 21/11/2024 12:30, Raviteja Laggyshetty wrote:
>>> Add Epoch Subsystem (EPSS) L3 interconnect provider binding on
>>> SA8775P SoCs.
>>
>> This we see from the diff. Explain the hardware, why adding epps-l3-perf.
>>
> The EPSS instance in SA8775P uses PERF_STATE register instead of REG_L3_VOTE to scale L3 clocks.Along with SoC specific compatible, add new generic compatible "qcom,epss-l3-perf" for PERF_STATE register based L3 scaling.
Pasting the same replies as you pasted to others won't solve the
problem. Solve the problem - fix the commit msg.
>
>>>
>>> Signed-off-by: Raviteja Laggyshetty <quic_rlaggysh@xxxxxxxxxxx>
>>> ---
>>> .../devicetree/bindings/interconnect/qcom,osm-l3.yaml | 4 ++++
>>> 1 file changed, 4 insertions(+)
>>>
>>> diff --git a/Documentation/devicetree/bindings/interconnect/qcom,osm-l3.yaml b/Documentation/devicetree/bindings/interconnect/qcom,osm-l3.yaml
>>> index 21dae0b92819..042ca44c32ec 100644
>>> --- a/Documentation/devicetree/bindings/interconnect/qcom,osm-l3.yaml
>>> +++ b/Documentation/devicetree/bindings/interconnect/qcom,osm-l3.yaml
>>> @@ -34,6 +34,10 @@ properties:
>>> - qcom,sm8250-epss-l3
>>> - qcom,sm8350-epss-l3
>>> - const: qcom,epss-l3
>>> + - items:
>>> + - enum:
>>> + - qcom,sa8775p-epss-l3
>>> + - const: qcom,epss-l3-perf
>>
>> I don't understand this change in context of driver. These are the same.
>> Isn't this compatible with sm8250?
>>
>
> The intention for adding "qcom,epss-l3-perf" generic compatible is to use it for the chipsets which use perf state register for l3 scaling.
> Using generic compatible avoids the need for adding chipset specific compatible in match table.
Not true, specific compatibles used as fallback do the same and is a
preferred way.
> But received comment from konrad to add both SoC-specific and generic compatibles.
I went through the history and don't see anything like that. Point to
the specific email please, if you disagree.
> Dmitry has suggested to update generic comaptibles for sc7280 and sm8250 SoCs, which makes use of perf state registers.
OK
> It will be done as separate patch series.
No. I expect to see full, correct picture, not half baked patches which
contradict what is in current code.
Best regards,
Krzysztof