From: Alex Hung <alex.h...@amd.com>

[WHY & HOW]
Some eDP panels suffer from flicking when HDR is enabled in KDE. This
quirk works around it by skipping VSC that is incompatible with eDP
panels.

Link: https://gitlab.freedesktop.org/drm/amd/-/issues/3151

Cc: Mario Limonciello <mario.limoncie...@amd.com>
Cc: Alex Deucher <alexander.deuc...@amd.com>
Cc: sta...@vger.kernel.org
Reviewed-by: Rodrigo Siqueira <rodrigo.sique...@amd.com>
Signed-off-by: Alex Hung <alex.h...@amd.com>
Signed-off-by: Aurabindo Pillai <aurabindo.pil...@amd.com>
---
 drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c     | 11 ++++++++++-
 .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c |  4 ++++
 drivers/gpu/drm/amd/display/dc/dc_types.h             |  1 +
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c 
b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
index 3fe7fe707a8a..3bf2db3b3059 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c
@@ -6735,12 +6735,21 @@ create_stream_for_sink(struct drm_connector *connector,
        if (stream->signal == SIGNAL_TYPE_DISPLAY_PORT ||
            stream->signal == SIGNAL_TYPE_DISPLAY_PORT_MST ||
            stream->signal == SIGNAL_TYPE_EDP) {
+               const struct dc_edid_caps *edid_caps;
+               unsigned int disable_colorimetry = 0;
+
+               if (aconnector->dc_sink) {
+                       edid_caps = &aconnector->dc_sink->edid_caps;
+                       disable_colorimetry = 
edid_caps->panel_patch.disable_colorimetry;
+               }
+
                //
                // should decide stream support vsc sdp colorimetry capability
                // before building vsc info packet
                //
                stream->use_vsc_sdp_for_colorimetry = 
stream->link->dpcd_caps.dpcd_rev.raw >= 0x14 &&
-                                                     
stream->link->dpcd_caps.dprx_feature.bits.VSC_SDP_COLORIMETRY_SUPPORTED;
+                                                     
stream->link->dpcd_caps.dprx_feature.bits.VSC_SDP_COLORIMETRY_SUPPORTED &&
+                                                     !disable_colorimetry;
 
                if (stream->out_transfer_func.tf == TRANSFER_FUNCTION_GAMMA22)
                        tf = TRANSFER_FUNC_GAMMA_22;
diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c 
b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
index 39b82c73a0dd..b62b0406a6d1 100644
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
+++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_helpers.c
@@ -73,6 +73,10 @@ static void apply_edid_quirks(struct edid *edid, struct 
dc_edid_caps *edid_caps)
                DRM_DEBUG_DRIVER("Clearing DPCD 0x317 on monitor with panel id 
%X\n", panel_id);
                edid_caps->panel_patch.remove_sink_ext_caps = true;
                break;
+       case drm_edid_encode_panel_id('S', 'D', 'C', 0x4154):
+               DRM_DEBUG_DRIVER("Disabling VSC on monitor with panel id %X\n", 
panel_id);
+               edid_caps->panel_patch.disable_colorimetry = true;
+               break;
        default:
                return;
        }
diff --git a/drivers/gpu/drm/amd/display/dc/dc_types.h 
b/drivers/gpu/drm/amd/display/dc/dc_types.h
index 2bbafd1cdce4..b0b7102fdbc7 100644
--- a/drivers/gpu/drm/amd/display/dc/dc_types.h
+++ b/drivers/gpu/drm/amd/display/dc/dc_types.h
@@ -178,6 +178,7 @@ struct dc_panel_patch {
        unsigned int skip_avmute;
        unsigned int mst_start_top_delay;
        unsigned int remove_sink_ext_caps;
+       unsigned int disable_colorimetry;
        uint8_t blankstream_before_otg_off;
 };
 
-- 
2.46.0

Reply via email to