Re: [PATCH v2 09/14] drm/msm/dpu: blend pipes per mixer pairs config

From: Dmitry Baryshkov
Date: Fri Oct 11 2024 - 03:03:15 EST


On Fri, 11 Oct 2024 at 09:40, Jun Nie <jun.nie@xxxxxxxxxx> wrote:
>
> Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> 于2024年10月10日周四 21:15写道:
> >
> > On Wed, Oct 09, 2024 at 04:50:22PM GMT, Jun Nie wrote:
> > > Blend pipes by set of mixer pair config. The first 2 pipes are for left
> > > half screen with the first set of mixer pair config. And the later 2 pipes
> > > are for right in quad pipe case.
> > >
> > > Signed-off-by: Jun Nie <jun.nie@xxxxxxxxxx>
> > > ---
> > > drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c | 38 ++++++++++++++++++-----------
> > > drivers/gpu/drm/msm/disp/dpu1/dpu_hw_mdss.h | 1 +
> > > 2 files changed, 25 insertions(+), 14 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> > > index 43d9817cd858f..66f745399a602 100644
> > > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> > > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> > > @@ -442,7 +442,7 @@ static void _dpu_crtc_blend_setup_mixer(struct drm_crtc *crtc,
> > > const struct msm_format *format;
> > > struct dpu_hw_ctl *ctl = mixer->lm_ctl;
> > >
> > > - uint32_t lm_idx, i;
> > > + uint32_t lm_idx, lm_pair, i, pipe_idx;
> > > bool bg_alpha_enable = false;
> > > DECLARE_BITMAP(fetch_active, SSPP_MAX);
> > >
> > > @@ -463,15 +463,20 @@ static void _dpu_crtc_blend_setup_mixer(struct drm_crtc *crtc,
> > > if (pstate->stage == DPU_STAGE_BASE && format->alpha_enable)
> > > bg_alpha_enable = true;
> > >
> > > - for (i = 0; i < PIPES_PER_LM_PAIR; i++) {
> > > - if (!pstate->pipe[i].sspp)
> > > - continue;
> > > - set_bit(pstate->pipe[i].sspp->idx, fetch_active);
> > > - _dpu_crtc_blend_setup_pipe(crtc, plane,
> > > - mixer, cstate->num_mixers,
> > > - pstate->stage,
> > > - format, fb ? fb->modifier : 0,
> > > - &pstate->pipe[i], i, stage_cfg);
> > > + /* loop pipe per mixer pair */
> > > + for (lm_pair = 0; lm_pair < PIPES_PER_PLANE / 2; lm_pair++) {
> > > + for (i = 0; i < PIPES_PER_LM_PAIR; i++) {
> > > + pipe_idx = i + lm_pair * PIPES_PER_LM_PAIR;
> > > + if (!pstate->pipe[pipe_idx].sspp)
> > > + continue;
> > > + set_bit(pstate->pipe[pipe_idx].sspp->idx, fetch_active);
> > > + _dpu_crtc_blend_setup_pipe(crtc, plane,
> > > + mixer, cstate->num_mixers,
> > > + pstate->stage,
> > > + format, fb ? fb->modifier : 0,
> > > + &pstate->pipe[pipe_idx], i,
> > > + &stage_cfg[lm_pair]);
> > > + }
> > > }
> > >
> > > /* blend config update */
> > > @@ -503,7 +508,7 @@ static void _dpu_crtc_blend_setup(struct drm_crtc *crtc)
> > > struct dpu_crtc_mixer *mixer = cstate->mixers;
> > > struct dpu_hw_ctl *ctl;
> > > struct dpu_hw_mixer *lm;
> > > - struct dpu_hw_stage_cfg stage_cfg;
> > > + struct dpu_hw_stage_cfg stage_cfg[LM_PAIRS_PER_PLANE];
> >
> > After seeing this code, can we define STAGES_PER_PLANE (and
> > also keep PLANES_PER_STAGE defined to 2)?
> >
> Could you elaborate it? Stages describe how many layers to be blended.
> Plane is a DRM concept that describe a buffer to be display in specific
> display driver. Plane is already mapped to SSPP/multi-rect in DPU driver
> in blending stage level. So I am confused here.

We have dpu_hw_stage_cfg, you are adding a second instance of it. So
we now have two stages per plane.

>
> - Jun



--
With best wishes
Dmitry