Re: [PATCH 3/4] drm/msm/dpu: Add has_data_compress to dpu_caps

From: Marijn Suijten
Date: Wed May 03 2023 - 19:03:44 EST


Hi Jessica,

On 2023-05-03 12:03:40, Jessica Zhang wrote:
>
>
> On 5/3/2023 12:07 AM, Marijn Suijten wrote:
> > On 2023-05-02 18:19:14, Jessica Zhang wrote:
> >> Add data_compress feature to DPU HW catalog.
> >>
> >> In DPU 7.x and later, there is a DATA_COMPRESS register that must be set
> >> within the DPU INTF block for DSC to work.
> >>
> >> As core_rev (and related macros) was removed from the dpu_kms struct, the
> >> most straightforward way to indicate the presence of this register would be
> >> to have a flag in dpu_caps.
> >
> > This is a very generic name to have in the global dpu_caps for a very
> > specific register on the INTF block since DPU >= 7.0.0, and I doubt any
> > new catalog contributor will know how to fill this field. After all,
> > DPU < 7.0.0 also has DCE but it is controlled via the PINGPONG block.
> >
> > Instead, how about having it as a DPU_INTF_DATA_COMPRESS (or similar)
> > feature flag on the INTF block? We do the same for other (register
> > related) features on the INTF block, and you did the same to disable DSC
> > callbacks on PP in [1].

(Note: I said "you" but meant Kuogee)

> Hi Marijn,
>
> Sounds good.
>
> >
> > In fact it seems that the DSC/DCE (enablement) registers have been moved
> > from PINGPONG to INTF in DPU 7.0.0. Can you clarify in the patch
> > message for v2 that this is the case, and do the same in the linked
> > PINGPONG patch? Perhaps these patches should be part of the same series
> > as they do not seem DSI-specific.
>
> Will make a note of the PP to INTF change in the commit message.

Thanks.

> I would prefer to keep this patch in this series is because it is needed
> for DSI over command mode to work and the subsequent patch is
> specifically for command mode.

That is fine, but do mention this in the commit message if it is
relevant here. Otherwise only mention it as part of patch 4/4.

- Marijn