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 proper min cdclk. v2: - Check for dsc enable and slice count ==1 then allow to double confirm min cdclk value. Cc: Ville Syrjala <ville.syrjala@xxxxxxxxxxxxxxx> Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx> Cc: Vandita Kulkarni <vandita.kulkarni@xxxxxxxxx> Cc: Cooper Chiou <cooper.chiou@xxxxxxxxx> Cc: William Tseng <william.tseng@xxxxxxxxx> Signed-off-by: Lee Shawn C <shawn.c.lee@xxxxxxxxx> --- drivers/gpu/drm/i915/display/intel_cdclk.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/gpu/drm/i915/display/intel_cdclk.c b/drivers/gpu/drm/i915/display/intel_cdclk.c index 34fa4130d5c4..9aec17b33819 100644 --- a/drivers/gpu/drm/i915/display/intel_cdclk.c +++ b/drivers/gpu/drm/i915/display/intel_cdclk.c @@ -2139,6 +2139,16 @@ int intel_crtc_compute_min_cdclk(const struct intel_crtc_state *crtc_state) /* Account for additional needs from the planes */ 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. + */ + if (crtc_state->dsc.compression_enable && + crtc_state->dsc.slice_count == 1) + min_cdclk = max(min_cdclk, (int)crtc_state->pixel_rate); + /* * HACK. Currently for TGL platforms we calculate * min_cdclk initially based on pixel_rate divided -- 2.17.1