drm/i915/vrr: Fix vmin/vmax/flipline on TGL when using vblank delay

Turns out that TGL needs its vmin/vmax/flipline adjusted based
on the vblank delay, otherwise the hardware pushes the vtotals
further out. Make it so.

Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20241210211007.5976-15-ville.syrjala@linux.intel.com
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>

diff --git a/drivers/gpu/drm/i915/display/intel_vrr.c b/drivers/gpu/drm/i915/display/intel_vrr.c
index 0f0c50265fc1bd5157687480acae5b53d0a603b3..1110f0e65e885f56f5261b8869f73b3bcb2cefe1 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_vrr.c
+++ b/drivers/gpu/drm/i915/display/intel_vrr.c
@@ -117,30 +117,41 @@ static int intel_vrr_vblank_exit_length(const struct intel_crtc_state *crtc_stat
        if (DISPLAY_VER(display) >= 13)
                return crtc_state->vrr.guardband;
        else
-               /* The hw imposes the extra scanline before frame start */
+               /* hardware imposes one extra scanline somewhere */
                return crtc_state->vrr.pipeline_full + crtc_state->framestart_delay + 1;
 }
 
 int intel_vrr_vmin_vtotal(const struct intel_crtc_state *crtc_state)
 {
+       struct intel_display *display = to_intel_display(crtc_state);
+
        /* Min vblank actually determined by flipline */
-       return intel_vrr_vmin_flipline(crtc_state);
+       if (DISPLAY_VER(display) >= 13)
+               return intel_vrr_vmin_flipline(crtc_state);
+       else
+               return intel_vrr_vmin_flipline(crtc_state) +
+                       intel_vrr_vblank_delay(crtc_state);
 }
 
 int intel_vrr_vmax_vtotal(const struct intel_crtc_state *crtc_state)
 {
-       return crtc_state->vrr.vmax;
+       struct intel_display *display = to_intel_display(crtc_state);
+
+       if (DISPLAY_VER(display) >= 13)
+               return crtc_state->vrr.vmax;
+       else
+               return crtc_state->vrr.vmax +
+                       intel_vrr_vblank_delay(crtc_state);
 }
 
 int intel_vrr_vmin_vblank_start(const struct intel_crtc_state *crtc_state)
 {
-       /* Min vblank actually determined by flipline */
-       return intel_vrr_vmin_flipline(crtc_state) - intel_vrr_vblank_exit_length(crtc_state);
+       return intel_vrr_vmin_vtotal(crtc_state) - intel_vrr_vblank_exit_length(crtc_state);
 }
 
 int intel_vrr_vmax_vblank_start(const struct intel_crtc_state *crtc_state)
 {
-       return crtc_state->vrr.vmax - intel_vrr_vblank_exit_length(crtc_state);
+       return intel_vrr_vmax_vtotal(crtc_state) - intel_vrr_vblank_exit_length(crtc_state);
 }
 
 static bool
@@ -289,9 +300,18 @@ void intel_vrr_compute_config_late(struct intel_crtc_state *crtc_state)
                crtc_state->vrr.guardband =
                        crtc_state->vrr.vmin - adjusted_mode->crtc_vblank_start;
        } else {
+               /* hardware imposes one extra scanline somewhere */
                crtc_state->vrr.pipeline_full =
                        min(255, crtc_state->vrr.vmin - adjusted_mode->crtc_vblank_start -
                            crtc_state->framestart_delay - 1);
+
+               /*
+                * vmin/vmax/flipline also need to be adjusted by
+                * the vblank delay to maintain correct vtotals.
+                */
+               crtc_state->vrr.vmin -= intel_vrr_vblank_delay(crtc_state);
+               crtc_state->vrr.vmax -= intel_vrr_vblank_delay(crtc_state);
+               crtc_state->vrr.flipline -= intel_vrr_vblank_delay(crtc_state);
        }
 }