[PATCH v11 1/2] drm/i915/vrr: Split vrr-compute-config in two phases

[Manna, Animesh]

> -----Original Message-----
> From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Sent: Friday, September 20, 2024 4:57 PM
> To: Manna, Animesh <animesh.manna at intel.com>
> Cc: intel-gfx at lists.freedesktop.org; Nikula, Jani <jani.nikula at intel.com>;
> Hogander, Jouni <jouni.hogander at intel.com>; Murthy, Arun R
> <arun.r.murthy at intel.com>; Nautiyal, Ankit K <ankit.k.nautiyal at intel.com>;
> Golani, Mitulkumar Ajitkumar <mitulkumar.ajitkumar.golani at intel.com>
> Subject: Re: [PATCH v11 1/2] drm/i915/vrr: Split vrr-compute-config in two
> phases
> 
> On Mon, Sep 16, 2024 at 01:24:05PM +0530, Animesh Manna wrote:
> > As vrr guardband calculation is dependent on modified vblank start so
> > better to compute late after all vblank adjustement.
> >
> > v1: Initial version.
> > v2: Split in a separate patch from panel-replay workaround. [Ankit]
> > v3: Add a function for late vrr related computation. [Ville]
> >
> > Signed-off-by: Animesh Manna <animesh.manna at intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_display.c |  2 ++
> >  drivers/gpu/drm/i915/display/intel_vrr.c     | 30 +++++++++++++-------
> >  drivers/gpu/drm/i915/display/intel_vrr.h     |  1 +
> >  3 files changed, 22 insertions(+), 11 deletions(-)
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_display.c
> > b/drivers/gpu/drm/i915/display/intel_display.c
> > index fdf244a32b24..111e61eceafc 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display.c
> > +++ b/drivers/gpu/drm/i915/display/intel_display.c
> > @@ -4802,6 +4802,8 @@ intel_modeset_pipe_config_late(struct
> intel_atomic_state *state,
> >  	struct drm_connector *connector;
> >  	int i;
> >
> > +	intel_vrr_compute_config_late(crtc_state);
> > +
> >  	for_each_new_connector_in_state(&state->base, connector,
> >  					conn_state, i) {
> >  		struct intel_encoder *encoder =
> > diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c
> > b/drivers/gpu/drm/i915/display/intel_vrr.c
> > index 9a51f5bac307..2de1c04bf1a5 100644
> > --- a/drivers/gpu/drm/i915/display/intel_vrr.c
> > +++ b/drivers/gpu/drm/i915/display/intel_vrr.c
> > @@ -239,18 +239,26 @@ intel_vrr_compute_config(struct intel_crtc_state
> *crtc_state,
> >  			(crtc_state->hw.adjusted_mode.crtc_vtotal -
> >  			 crtc_state->hw.adjusted_mode.vsync_end);
> >  	}
> > +}
> >
> > -	/*
> > -	 * For XE_LPD+, we use guardband and pipeline override
> > -	 * is deprecated.
> > -	 */
> > -	if (DISPLAY_VER(display) >= 13) {
> > -		crtc_state->vrr.guardband =
> > -			crtc_state->vrr.vmin + 1 - adjusted_mode-
> >crtc_vblank_start;
> > -	} else {
> > -		crtc_state->vrr.pipeline_full =
> > -			min(255, crtc_state->vrr.vmin - adjusted_mode-
> >crtc_vblank_start -
> > -			    crtc_state->framestart_delay - 1);
> > +void intel_vrr_compute_config_late(struct intel_crtc_state
> > +*crtc_state) {
> > +	struct intel_display *display = to_intel_display(crtc_state);
> > +	struct drm_display_mode *adjusted_mode =
> > +&crtc_state->hw.adjusted_mode;
> > +
> > +	if (crtc_state->vrr.enable) {
> 
> Never use that. VRR state must be computed correctly even when VRR is not
> actually enabled. That is how we can simply toggle VRR during fastsets.
> 
> You want to check vrr.flipline just like
> intel_vrr_set_transcoder_timings() does. We should perhaps add a helper
> with a decent name for that purpose. intel_vrr_possible() perhaps?

Got it, will take care in next version.

> 
> Also flip this condition around to eliminate the nasty whole function
> indentation.

Ok.

Regards,
Animesh
> 
> > +		/*
> > +		 * For XE_LPD+, we use guardband and pipeline override
> > +		 * is deprecated.
> > +		 */
> 
> Could drop that redundant comment while at it.
> 
> > +		if (DISPLAY_VER(display) >= 13) {
> > +			crtc_state->vrr.guardband =
> > +				crtc_state->vrr.vmin + 1 - adjusted_mode-
> >crtc_vblank_start;
> > +		} else {
> > +			crtc_state->vrr.pipeline_full =
> > +				min(255, crtc_state->vrr.vmin -
> adjusted_mode->crtc_vblank_start -
> > +				crtc_state->framestart_delay - 1);
> > +		}
> >  	}
> >  }
> >
> > diff --git a/drivers/gpu/drm/i915/display/intel_vrr.h
> > b/drivers/gpu/drm/i915/display/intel_vrr.h
> > index 89937858200d..3127c94e9778 100644
> > --- a/drivers/gpu/drm/i915/display/intel_vrr.h
> > +++ b/drivers/gpu/drm/i915/display/intel_vrr.h
> > @@ -18,6 +18,7 @@ bool intel_vrr_is_in_range(struct intel_connector
> > *connector, int vrefresh);  void intel_vrr_check_modeset(struct
> > intel_atomic_state *state);  void intel_vrr_compute_config(struct
> intel_crtc_state *crtc_state,
> >  			      struct drm_connector_state *conn_state);
> > +void intel_vrr_compute_config_late(struct intel_crtc_state
> > +*crtc_state);
> >  void intel_vrr_set_transcoder_timings(const struct intel_crtc_state
> > *crtc_state);  void intel_vrr_enable(const struct intel_crtc_state
> > *crtc_state);  void intel_vrr_send_push(const struct intel_crtc_state
> > *crtc_state);
> > --
> > 2.29.0
> 
> --
> Ville Syrjälä
> Intel