Re: [PATCH v2 06/11] drm/msm/disp/dpu1: Don't use DSC with mode_3d

[Vinod Koul <vkoul@kernel.org>]

On 14-10-21, 16:50, Dmitry Baryshkov wrote:
> On 14/10/2021 16:41, Dmitry Baryshkov wrote:
> > On 07/10/2021 10:08, Vinod Koul wrote:
> > > We cannot enable mode_3d when we are using the DSC. So pass
> > > configuration to detect DSC is enabled and not enable mode_3d
> > > when we are using DSC
> > > 
> > > We add a helper dpu_encoder_helper_get_dsc_mode() to detect dsc
> > > enabled and pass this to .setup_intf_cfg()
> > > 
> > > Signed-off-by: Vinod Koul <vkoul@kernel.org>
> > > ---
> > > Changes since
> > > v1:
> > >   - Move this patch from 7 to 6
> > >   - Update the changelog
> > >   - Make dsc as int and store the DSC indices
> > > 
> > >   drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h     | 11 +++++++++++
> > >   drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_cmd.c |  2 ++
> > >   drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.c           |  5 +++--
> > >   drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.h           |  2 ++
> > >   4 files changed, 18 insertions(+), 2 deletions(-)
> > > 
> > > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h
> > > b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h
> > > index e7270eb6b84b..fca07ed03317 100644
> > > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h
> > > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys.h
> > > @@ -332,6 +332,17 @@ static inline enum dpu_3d_blend_mode
> > > dpu_encoder_helper_get_3d_blend_mode(
> > >       return BLEND_3D_NONE;
> > >   }
> > > +static inline bool dpu_encoder_helper_get_dsc_mode(struct
> > > dpu_encoder_phys *phys_enc)
> > > +{
> > > +    struct drm_encoder *drm_enc = phys_enc->parent;
> > > +    struct msm_drm_private *priv = drm_enc->dev->dev_private;
> > > +
> > > +    if (priv->dsc)
> > > +        return BIT(0) | BIT(1); /* Hardcoding for 2 DSC topology */
> > 
> > Please use defined values here rater than just BIT().
> 
> Ah, it's a list of DSC blocks used. So the function name is misleading (as
> it's not a mode). I think we'd better pass DSC_n names here. What about
> using an array for cfg->dsc?

Yeah I can do better names.

> 
> > 
> > > +
> > > +    return 0;
> > > +}
> > > +
> > >   /**
> > >    * dpu_encoder_helper_split_config - split display configuration
> > > helper function
> > >    *    This helper function may be used by physical encoders to
> > > configure
> > > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_cmd.c
> > > b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_cmd.c
> > > index aa01698d6b25..8e5c0911734c 100644
> > > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_cmd.c
> > > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_encoder_phys_cmd.c
> > > @@ -70,6 +70,8 @@ static void _dpu_encoder_phys_cmd_update_intf_cfg(
> > >       intf_cfg.intf_mode_sel = DPU_CTL_MODE_SEL_CMD;
> > >       intf_cfg.stream_sel = cmd_enc->stream_sel;
> > >       intf_cfg.mode_3d = dpu_encoder_helper_get_3d_blend_mode(phys_enc);
> > > +    intf_cfg.dsc = dpu_encoder_helper_get_dsc_mode(phys_enc);
> > > +
> > >       ctl->ops.setup_intf_cfg(ctl, &intf_cfg);
> > >   }
> > > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.c
> > > b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.c
> > > index 64740ddb983e..3c79bd9c2fe5 100644
> > > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.c
> > > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.c
> > > @@ -118,7 +118,7 @@ static u32 dpu_hw_ctl_get_pending_flush(struct
> > > dpu_hw_ctl *ctx)
> > >       return ctx->pending_flush_mask;
> > >   }
> > > -static inline void dpu_hw_ctl_trigger_flush_v1(struct dpu_hw_ctl *ctx)
> > > +static void dpu_hw_ctl_trigger_flush_v1(struct dpu_hw_ctl *ctx)
> > >   {
> > >       if (ctx->pending_flush_mask & BIT(MERGE_3D_IDX))
> > > @@ -519,7 +519,8 @@ static void dpu_hw_ctl_intf_cfg(struct
> > > dpu_hw_ctl *ctx,
> > >       intf_cfg |= (cfg->intf & 0xF) << 4;
> > > -    if (cfg->mode_3d) {
> > > +    /* In DSC we can't set merge, so check for dsc too */
> > > +    if (cfg->mode_3d && !cfg->dsc) {
> > 
> > The more I think about this hunk, the more I'm unsure about it.
> > Downstream has the following topoligies defined:
> >   * @SDE_RM_TOPOLOGY_DUALPIPE_3DMERGE_DSC: 2 LM, 2 PP, 3DMux, 1 DSC, 1
> > INTF/WB
> >   * @SDE_RM_TOPOLOGY_QUADPIPE_3DMERGE_DSC  4 LM, 4 PP, 3DMux, 3 DSC, 2 INTF
> > 
> > While the latter is not supported on sdm845, the former one should be
> > (by the hardware). So in the driver I think we should make sure that
> > mode_3d does not get set rather than disallowing it here.
> > 
> > >           intf_cfg |= BIT(19);
> > >           intf_cfg |= (cfg->mode_3d - 0x1) << 20;
> > >       }
> > > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.h
> > > b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.h
> > > index 806c171e5df2..5dfac5994bd4 100644
> > > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.h
> > > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_hw_ctl.h
> > > @@ -39,6 +39,7 @@ struct dpu_hw_stage_cfg {
> > >    * @mode_3d:               3d mux configuration
> > >    * @merge_3d:              3d merge block used
> > >    * @intf_mode_sel:         Interface mode, cmd / vid
> > > + * @dsc:                   DSC BIT masks
> > >    * @stream_sel:            Stream selection for multi-stream interfaces
> > >    */
> > >   struct dpu_hw_intf_cfg {
> > > @@ -46,6 +47,7 @@ struct dpu_hw_intf_cfg {
> > >       enum dpu_3d_blend_mode mode_3d;
> > >       enum dpu_merge_3d merge_3d;
> > >       enum dpu_ctl_mode_sel intf_mode_sel;
> > > +    unsigned int dsc;
> 
> I think this should be:
> enum dpu_dsc dsc[MAX_DSCS];
> unsigned int num_dsc;

hmmm, how do we go about getting the num_dsc value here.
dpu_encoder_phys does not know about that..

-- 
~Vinod