[RFC PATCH] drm/msm/dpu: check ubwc support before adding compressed formats

[Dmitry Baryshkov]

On Fri, 28 Jun 2024 at 08:44, Abhinav Kumar <quic_abhinavk at quicinc.com> wrote:
>
>
>
> On 6/27/2024 4:22 PM, Dmitry Baryshkov wrote:
> > On Fri, 28 Jun 2024 at 00:21, Abhinav Kumar <quic_abhinavk at quicinc.com> wrote:
> >>
> >>
> >>
> >> On 6/27/2024 2:13 PM, Rob Clark wrote:
> >>> On Thu, Jun 27, 2024 at 1:53 PM Abhinav Kumar <quic_abhinavk at quicinc.com> wrote:
> >>>>
> >>>> On QCM2290 chipset DPU does not support UBWC.
> >>>>
> >>>> Add a dpu cap to indicate this and do not expose compressed formats
> >>>> in this case.
> >>>>
> >>>> Signed-off-by: Abhinav Kumar <quic_abhinavk at quicinc.com>
> >>>> ---
> >>>>    drivers/gpu/drm/msm/disp/dpu1/catalog/dpu_6_5_qcm2290.h | 1 +
> >>>>    drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.h          | 2 ++
> >>>>    drivers/gpu/drm/msm/disp/dpu1/dpu_plane.c               | 5 ++++-
> >>>>    3 files changed, 7 insertions(+), 1 deletion(-)
> >>>>
> >>>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/catalog/dpu_6_5_qcm2290.h b/drivers/gpu/drm/msm/disp/dpu1/catalog/dpu_6_5_qcm2290.h
> >>>> index 3cbb2fe8aba2..6671f798bacc 100644
> >>>> --- a/drivers/gpu/drm/msm/disp/dpu1/catalog/dpu_6_5_qcm2290.h
> >>>> +++ b/drivers/gpu/drm/msm/disp/dpu1/catalog/dpu_6_5_qcm2290.h
> >>>> @@ -12,6 +12,7 @@ static const struct dpu_caps qcm2290_dpu_caps = {
> >>>>           .max_mixer_blendstages = 0x4,
> >>>>           .has_dim_layer = true,
> >>>>           .has_idle_pc = true,
> >>>> +       .has_no_ubwc = true,
> >>>>           .max_linewidth = 2160,
> >>>>           .pixel_ram_size = DEFAULT_PIXEL_RAM_SIZE,
> >>>>    };
> >>>> diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.h
> >>>> index af2ead1c4886..676d0a283922 100644
> >>>> --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.h
> >>>> +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_catalog.h
> >>>> @@ -342,6 +342,7 @@ struct dpu_rotation_cfg {
> >>>>     * @has_dim_layer      dim layer feature status
> >>>>     * @has_idle_pc        indicate if idle power collapse feature is supported
> >>>>     * @has_3d_merge       indicate if 3D merge is supported
> >>>> + * @has_no_ubwc        indicate if UBWC is supported
> >>>>     * @max_linewidth      max linewidth for sspp
> >>>>     * @pixel_ram_size     size of latency hiding and de-tiling buffer in bytes
> >>>>     * @max_hdeci_exp      max horizontal decimation supported (max is 2^value)
> >>>> @@ -354,6 +355,7 @@ struct dpu_caps {
> >>>>           bool has_dim_layer;
> >>>>           bool has_idle_pc;
> >>>>           bool has_3d_merge;
> >>>> +       bool has_no_ubwc;
> >>>
> >>> has_no_ubwc sounds kinda awkward compared to has_ubwc.  But I guess
> >>> you wanted to avoid all that churn..
> >>>
> >>
> >> Yes I wanted to avoid modifying all the catalogs.
> >>
> >>> How about instead, if msm_mdss_data::ubwc_{enc,dec}_version are zero,
> >>> then we know there is no ubwc support in the display.
> >>>
> >>
> >> hmm ... should work .... I can post a v2 with this and avoid touching
> >> the catalog altogether.
> >
> > Yes, this sounds much better.
> >
>
> Ok, does this qualify for a Fixes tag too? Because exposing ubwc formats
> on non-ubwc supported chipsets seems like a bug.

I think it does.
For example, I've also added Fixes: to the patch disabling YUV on qcm2290.

-- 
With best wishes
Dmitry