[PATCH 1/9] dt-bindings: msm/dp: drop extra p1 region

[Dmitry Baryshkov]

On 08/07/2022 22:47, Kuogee Hsieh wrote:
> 
> On 7/8/2022 12:38 PM, Abhinav Kumar wrote:
>> + kuogee
>>
>> On 7/8/2022 12:27 PM, Stephen Boyd wrote:
>>> Quoting Dmitry Baryshkov (2022-07-07 20:46:43)
>>>> On 08/07/2022 04:28, Stephen Boyd wrote:
>>>>> Quoting Dmitry Baryshkov (2022-07-07 14:31:56)
>>>>>> The p1 region was probably added by mistake, none of the DTS files
>>>>>> provides one (and the driver source code also doesn't use one). 
>>>>>> Drop it
>>>>>> now.
>>>>>
>>>>> Yes, looks like the driver doesn't use it.
>>>>>
>>>>>>
>>>>>> Fixes: 687825c402f1 ("dt-bindings: msm/dp: Change reg definition")
>>>>>> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
>>>>>> ---
>>>>>> Documentation/devicetree/bindings/display/msm/dp-controller.yaml | 
>>>>>> 1 -
>>>>>>    1 file changed, 1 deletion(-)
>>>>>>
>>>>>> diff --git 
>>>>>> a/Documentation/devicetree/bindings/display/msm/dp-controller.yaml 
>>>>>> b/Documentation/devicetree/bindings/display/msm/dp-controller.yaml
>>>>>> index 94bc6e1b6451..d6bbe58ef9e8 100644
>>>>>> --- 
>>>>>> a/Documentation/devicetree/bindings/display/msm/dp-controller.yaml
>>>>>> +++ 
>>>>>> b/Documentation/devicetree/bindings/display/msm/dp-controller.yaml
>>>>>> @@ -29,7 +29,6 @@ properties:
>>>>>>          - description: aux register block
>>>>>>          - description: link register block
>>>>>>          - description: p0 register block
>>>>>> -      - description: p1 register block
>>>>>
>>>>> The p1 registers exist on sc7180. They start where the example starts,
>>>>> at 0xae91400.
>>>>
>>>> Do they exist on e.g. sc7280? In other words, should we add the region
>>>> to the DTS? For now I'm going to mark it as optional.
>>>>
>>>
>>> Yes I see the same address for P1 on sc7280. Maybe it's a typo? Abhinav,
>>> can you confirm?
>>
>> P1 block does exist on sc7280 and yes its address is same as the 
>> address mentioned in sc7180. So its not a typo.
>>
>> Yes, we are not programming this today but I would prefer to keep this 
>> as optional.
>>
>> I did sync up with Kuogee on this change this morning, we will check a 
>> few things internally on the P1 block's usage as to which use-cases we 
>> need to program it for and update here.
>>
> P1 block is for dp MST application.  This allow two dp streams can be 
> mux into same DP phy.
> 
> We should keep it since we may support MST later.

Thanks for the confirmation. Next question, does it exist on eDP 
controllers?

> 
>> The idea behind having this register space listed in the yaml is thats 
>> how the software documents have the blocks listed so dropping P1 block 
>> just because its unused seemed wrong to me. Optional seems more 
>> appropriate.
>>
>> Thanks
>>
>> Abhinav


-- 
With best wishes
Dmitry