[PATCH v4 9/9] drm/msm/dpu: drop dpu_core_perf_params::max_per_pipe_ib

[Dmitry Baryshkov]

On Tue, Jan 14, 2025 at 04:53:10PM -0800, Abhinav Kumar wrote:
> 
> 
> On 1/5/2025 7:07 PM, Dmitry Baryshkov wrote:
> > The max_per_pipe_ib is a constant across all CRTCs and is read from the
> > catalog. The override value is also applied at the
> > _dpu_core_perf_crtc_update_bus() time. Drop corresponding calculations
> > and read the value directly at icc_set_bw() time.
> > 
> > Suggested-by: Konrad Dybcio <konrad.dybcio at linaro.org>
> > Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
> > ---
> >   drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c | 16 ++++------------
> >   drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.h |  2 --
> >   drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c      |  2 --
> >   3 files changed, 4 insertions(+), 16 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c
> > index 913eb4c01abe10c1ed84215fbbee50abd69e9317..62dab5883513dc570076da5a64e32e502dd4320b 100644
> > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c
> > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.c
> > @@ -105,12 +105,10 @@ static void _dpu_core_perf_calc_crtc(const struct dpu_core_perf *core_perf,
> >   	}
> >   	perf->bw_ctl = _dpu_core_perf_calc_bw(perf_cfg, crtc);
> > -	perf->max_per_pipe_ib = perf_cfg->min_dram_ib;
> >   	perf->core_clk_rate = _dpu_core_perf_calc_clk(perf_cfg, crtc, state);
> >   	DRM_DEBUG_ATOMIC(
> > -		"crtc=%d clk_rate=%llu core_ib=%u core_ab=%u\n",
> > +		"crtc=%d clk_rate=%llu core_ab=%u\n",
> >   			crtc->base.id, perf->core_clk_rate,
> > -			perf->max_per_pipe_ib,
> >   			(u32)DIV_ROUND_UP_ULL(perf->bw_ctl, 1000));
> >   }
> > @@ -126,9 +124,6 @@ static void dpu_core_perf_aggregate(struct drm_device *ddev,
> >   		    curr_client_type == dpu_crtc_get_client_type(tmp_crtc)) {
> >   			dpu_cstate = to_dpu_crtc_state(tmp_crtc->state);
> > -			perf->max_per_pipe_ib = max(perf->max_per_pipe_ib,
> > -						    dpu_cstate->new_perf.max_per_pipe_ib);
> 
> During the enabled cases, this is fine since even if one crtc is enabled,
> its going to use the same value.
> 
> During disable to enable and enable to disable transitions, we do need to
> make it 0 right?

Good point, I will check that later.

> 
> OR if its already being made 0, we need to make sure it gets updated by
> forcing update_bus to true?
> 
> Is this part being handled by this block dpu_core_perf_crtc_update()?
> 
>         } else {
>                 DRM_DEBUG_ATOMIC("crtc=%d disable\n", crtc->base.id);
>                 memset(old, 0, sizeof(*old));
>                 update_bus = true;
>                 update_clk = true;
>         }
> 
> Please confirm this, I am fine with this change otherwise.
> 
> > -
> >   			perf->bw_ctl += dpu_cstate->new_perf.bw_ctl;
> >   			DRM_DEBUG_ATOMIC("crtc=%d bw=%llu\n",
> > @@ -204,7 +199,7 @@ static int _dpu_core_perf_crtc_update_bus(struct dpu_kms *kms,
> >   	dpu_core_perf_aggregate(crtc->dev, dpu_crtc_get_client_type(crtc), &perf);
> >   	avg_bw = div_u64(perf.bw_ctl, 1000); /*Bps_to_icc*/
> > -	peak_bw = perf.max_per_pipe_ib;
> > +	peak_bw = kms->catalog->perf->min_dram_ib;
> >   	if (kms->perf.fix_core_ab_vote)
> >   		avg_bw = kms->perf.fix_core_ab_vote;
> > @@ -315,15 +310,12 @@ int dpu_core_perf_crtc_update(struct drm_crtc *crtc,
> >   		 * 2. new bandwidth vote - "ab or ib vote" is lower
> >   		 *    than current vote at end of commit or stop.
> >   		 */
> > -		if ((params_changed && ((new->bw_ctl > old->bw_ctl) ||
> > -			(new->max_per_pipe_ib > old->max_per_pipe_ib)))	||
> > -			(!params_changed && ((new->bw_ctl < old->bw_ctl) ||
> > -			(new->max_per_pipe_ib < old->max_per_pipe_ib)))) {
> > +		if ((params_changed && new->bw_ctl > old->bw_ctl) ||
> > +		    (!params_changed && new->bw_ctl < old->bw_ctl)) {
> >   			DRM_DEBUG_ATOMIC("crtc=%d p=%d new_bw=%llu,old_bw=%llu\n",
> >   				crtc->base.id, params_changed,
> >   				new->bw_ctl, old->bw_ctl);
> >   			old->bw_ctl = new->bw_ctl;
> > -			old->max_per_pipe_ib = new->max_per_pipe_ib;
> >   			update_bus = true;
> >   		}
> > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.h b/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.h
> > index 9d8516ca32d162b1e277ec88067e5c21abeb2017..863a6fc1f30c21cf2030a30be5fe62b024b3b820 100644
> > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.h
> > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_core_perf.h
> > @@ -14,12 +14,10 @@
> >   /**
> >    * struct dpu_core_perf_params - definition of performance parameters
> > - * @max_per_pipe_ib: maximum instantaneous bandwidth request
> >    * @bw_ctl: arbitrated bandwidth request
> >    * @core_clk_rate: core clock rate request
> >    */
> >   struct dpu_core_perf_params {
> > -	u32 max_per_pipe_ib;
> >   	u64 bw_ctl;
> >   	u64 core_clk_rate;
> >   };
> > diff --git a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> > index ac3c6c5ad1cec3856f0eff2ed71153d3c2dc279e..cc240d3c7faa89254a575237634d0d0fa8f04f73 100644
> > --- a/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> > +++ b/drivers/gpu/drm/msm/disp/dpu1/dpu_crtc.c
> > @@ -1488,8 +1488,6 @@ static int dpu_crtc_debugfs_state_show(struct seq_file *s, void *v)
> >   			dpu_crtc->cur_perf.core_clk_rate);
> >   	seq_printf(s, "bw_ctl: %uk\n",
> >   		   (u32)DIV_ROUND_UP_ULL(dpu_crtc->cur_perf.bw_ctl, 1000));
> > -	seq_printf(s, "max_per_pipe_ib: %u\n",
> > -				dpu_crtc->cur_perf.max_per_pipe_ib);
> >   	return 0;
> >   }
> > 

-- 
With best wishes
Dmitry