For DP 1.4 and above, Display Stream compression can be enabled only if Forward Error Correctin can be performed. Check if the sink supports FEC using the helper. v2: Mention External DP where ever FEC is mentioned in the code.Check return status of dpcd reads. (Gaurav) - Do regular mode check even if FEC is not supported. (manasi) v3: Do not perform any dpcd writes in the atomic check phase. (DK, Manasi) v4: Use debug level logging for scenario where sink does not support a feature. (DK) v5: Correct commit message. rebase. v6: pass single field instead of an array for helper function. (manasi) Cc: Gaurav K Singh <gaurav.k.singh@xxxxxxxxx> Cc: Ville Syrjala <ville.syrjala@xxxxxxxxxxxxxxx> Cc: Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx> Cc: Manasi Navare <manasi.d.navare@xxxxxxxxx> Cc: Dhinakaran Pandiyan <dhinakaran.pandiyan@xxxxxxxxx> Signed-off-by: Anusha Srivatsa <anusha.srivatsa@xxxxxxxxx> Reviewed-by: Manasi Navare <manasi.d.navare@xxxxxxxxx> --- drivers/gpu/drm/i915/intel_dp.c | 12 ++++++++++-- 1 file changed, 10 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 16d1db7c9398..cfcef9e4b5d9 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -680,7 +680,7 @@ intel_dp_mode_valid(struct drm_connector *connector, dsc_slice_count = drm_dp_dsc_sink_max_slice_count(intel_dp->dsc_dpcd, true); - } else { + } else if (drm_dp_sink_supports_fec(intel_dp->fec_capable)) { dsc_max_output_bpp = intel_dp_dsc_get_output_bpp(max_link_clock, max_lanes, @@ -690,7 +690,8 @@ intel_dp_mode_valid(struct drm_connector *connector, intel_dp_dsc_get_slice_count(intel_dp, target_clock, mode->hdisplay); - } + } else + DRM_DEBUG_KMS("Sink device does not Support FEC\n"); } if ((mode_rate > max_rate && !(dsc_max_output_bpp && dsc_slice_count)) || @@ -2063,6 +2064,13 @@ static bool intel_dp_dsc_compute_config(struct intel_dp *intel_dp, if (pipe == PIPE_A && !intel_dp_is_edp(intel_dp)) return false; + /* DSC not supported if external DP sink does not support FEC */ + if (!intel_dp_is_edp(intel_dp) && + !drm_dp_sink_supports_fec(intel_dp->fec_capable)) { + DRM_DEBUG_KMS("Sink does not support Forward Error Correction, disabling Display Compression\n"); + return false; + } + /* DSC not supported for DSC sink BPC < 8 */ if (limits->max_bpp < 3 * DP_DSC_MIN_SUPPORTED_BPC) { DRM_DEBUG_KMS("No DSC support for less than 8bpc\n"); -- 2.17.1 _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx