Re: [PATCH v2 05/16] dt-bindings: display/msm: dp-controller: Add SM8750

[Abhinav Kumar <quic_abhinavk@quicinc.com>]

On 2/19/2025 9:08 AM, Dmitry Baryshkov wrote:
> On Wed, Feb 19, 2025 at 06:02:20PM +0100, Krzysztof Kozlowski wrote:
>> On 17/02/2025 19:58, Dmitry Baryshkov wrote:
>>> On Mon, Feb 17, 2025 at 05:41:26PM +0100, Krzysztof Kozlowski wrote:
>>>> Add DisplayPort controller for Qualcomm SM8750 SoC which so far looks
>>>> fully compatible with earlier SM8650 variant.
>>>
>>> As that became a question for QCS8300, does SM8750 also support exactly
>>> two MST streams?
>>
>> v1.5 of DP (starting from SA8775p , then SM8650 and SM8750) support 4x
>> MST for DPTX0 and 2x MST for DPTX1.
>>
>> The DP in SM8650 and SM8750 are identical, according to datasheet (v1.5.1).
> 
> Hmm. This also means that QCS8300 is compatible with SM8650. I'll let
> Abhinav comment here.
> 

DP version by itself is not a good measure of whether the controller can 
support 4 streams or not.

Firstly, sm8650/sm8750 do not have a DPTX1 so we are only discussing 
about DP TX0.

Coming to the QCS8300 Vs sm8650/sm8750, even though the DP controller 
version is the same, there is no HW support for more than 2 streams on 
sm8650/sm8750 because there are no INTF blocks to drive 4 streams.

On sm8650/sm8750, only INTF_0 and INTF_3 can be used for DP. Hence 2 
streams.

Whereas on Monaco, we have INTF_0, INTF_3, INTF_6 and INTF_7 capable of 
driving DP. Hence 4 streams.

Let me know if there are more questions.

Thanks

Abhinav