[Intel-gfx] [PATCH] drm/i915/display: Fix the dsc check while selecting min_cdclk

Vandita Kulkarni vandita.kulkarni at intel.com
Wed Sep 15 05:43:38 UTC 2021


The right parameter that selects second dsc engine is dsc_split.
Hence use dsc_split instead of slice_count while selecting the
cdclk in order to accommodate 1ppc limitaion of vdsc.

Fixes: fe01883fdcef ("drm/i915: Get proper min cdclk if vDSC enabled")
Suggested-by: Jani Nikula <jani.nikula at intel.com>
Signed-off-by: Vandita Kulkarni <vandita.kulkarni at intel.com>
---
 drivers/gpu/drm/i915/display/intel_cdclk.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_cdclk.c b/drivers/gpu/drm/i915/display/intel_cdclk.c
index 9aec17b33819..3a1cdb3937aa 100644
--- a/drivers/gpu/drm/i915/display/intel_cdclk.c
+++ b/drivers/gpu/drm/i915/display/intel_cdclk.c
@@ -2140,13 +2140,11 @@ int intel_crtc_compute_min_cdclk(const struct intel_crtc_state *crtc_state)
 	min_cdclk = max(intel_planes_min_cdclk(crtc_state), min_cdclk);
 
 	/*
-	 * VDSC engine can process only 1 pixel per Cd clock.
-	 * In case VDSC is used and max slice count == 1,
-	 * max supported pixel clock should be 100% of CD clock.
-	 * Then do min_cdclk and pixel clock comparison to get cdclk.
+	 * When we decide to use only one VDSC engine, since
+	 * each VDSC operates with 1 ppc throughput, pixel clock
+	 * cannot be higher than the VDSC clock (cdclk)
 	 */
-	if (crtc_state->dsc.compression_enable &&
-	    crtc_state->dsc.slice_count == 1)
+	if (crtc_state->dsc.compression_enable && !crtc_state->dsc.dsc_split)
 		min_cdclk = max(min_cdclk, (int)crtc_state->pixel_rate);
 
 	/*
-- 
2.32.0



More information about the Intel-gfx mailing list