[PATCH 05/20] drm/i915/vrr: Track vrr.enable only for variable timing

[Ville Syrjälä]

On Mon, Feb 24, 2025 at 11:47:02AM +0530, Ankit Nautiyal wrote:
> Since CMRR is now disabled, use the flag vrr.enable to tracks if vrr timing
> generator is used with variable timings.
> 
> Avoid setting vrr.enable for CMRR and adjust readout to not set vrr.enable
> when vmax == vmin == flipline (fixed refresh rate timing).
> 
> v2: Use intel_vrr_vmin_flipline() to account for adjustments required
> for icl/tgl. (Ville)
> 
> Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_vrr.c | 13 +++++++++++--
>  1 file changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c b/drivers/gpu/drm/i915/display/intel_vrr.c
> index 0ee7fb0362ce..4d7f29be55b8 100644
> --- a/drivers/gpu/drm/i915/display/intel_vrr.c
> +++ b/drivers/gpu/drm/i915/display/intel_vrr.c
> @@ -226,7 +226,6 @@ cmrr_get_vtotal(struct intel_crtc_state *crtc_state, bool video_mode_required)
>  static
>  void intel_vrr_compute_cmrr_timings(struct intel_crtc_state *crtc_state)
>  {
> -	crtc_state->vrr.enable = true;
>  	crtc_state->cmrr.enable = true;
>  	/*
>  	 * TODO: Compute precise target refresh rate to determine
> @@ -528,6 +527,14 @@ void intel_vrr_disable(const struct intel_crtc_state *old_crtc_state)
>  	intel_de_write(display, TRANS_PUSH(display, cpu_transcoder), 0);
>  }
>  
> +static
> +bool intel_vrr_is_fixed_rr(const struct intel_crtc_state *crtc_state)
> +{
> +	return crtc_state->vrr.flipline &&
> +	       crtc_state->vrr.flipline == crtc_state->vrr.vmax &&
> +	       crtc_state->vrr.flipline == intel_vrr_vmin_flipline(crtc_state);
> +}
> +
>  void intel_vrr_get_config(struct intel_crtc_state *crtc_state)
>  {
>  	struct intel_display *display = to_intel_display(crtc_state);
> @@ -537,7 +544,6 @@ void intel_vrr_get_config(struct intel_crtc_state *crtc_state)
>  	trans_vrr_ctl = intel_de_read(display,
>  				      TRANS_VRR_CTL(display, cpu_transcoder));
>  
> -	crtc_state->vrr.enable = trans_vrr_ctl & VRR_CTL_VRR_ENABLE;
>  	if (HAS_CMRR(display))
>  		crtc_state->cmrr.enable = (trans_vrr_ctl & VRR_CTL_CMRR_ENABLE);
>  
> @@ -577,6 +583,9 @@ void intel_vrr_get_config(struct intel_crtc_state *crtc_state)
>  		}
>  	}
>  
> +	crtc_state->vrr.enable = trans_vrr_ctl & VRR_CTL_VRR_ENABLE &&
> +				 !intel_vrr_is_fixed_rr(crtc_state);
> +
>  	if (crtc_state->vrr.enable)
>  		crtc_state->mode_flags |= I915_MODE_FLAG_VRR;

This thing is now inconsistent for CMRR, but since that's disabled now
I guess we don't really care. Just need to keep this in mind when we
fix up CMRR.

Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>

>  }
> -- 
> 2.45.2

-- 
Ville Syrjälä
Intel