6.17-stable review patch. If anyone has any objections, please let me know.
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From: Mario Limonciello Mario.Limonciello@amd.com
[ Upstream commit db291ed1732e02e79dca431838713bbf602bda1c ]
[Why] DP validation may fail with multiple displays and higher color depths. The sink may support others though.
[How] When DP bandwidth validation fails, progressively fallback through: - YUV422 8bpc (bandwidth efficient) - YUV422 6bpc (reduced color depth) - YUV420 (last resort)
This resolves cases where displays would show no image due to insufficient DP link bandwidth for the requested RGB mode.
Suggested-by: Mauri Carvalho mcarvalho3@lenovo.com Reviewed-by: Wayne Lin wayne.lin@amd.com Signed-off-by: Mario Limonciello Mario.Limonciello@amd.com Signed-off-by: Ray Wu ray.wu@amd.com Tested-by: Daniel Wheeler daniel.wheeler@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 45 +++++++++++++++---- .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h | 1 + 2 files changed, 37 insertions(+), 9 deletions(-)
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 60eb2c2c79b77..e3e9faa4aaeb7 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -6405,7 +6405,8 @@ static void fill_stream_properties_from_drm_display_mode( && aconnector->force_yuv420_output) timing_out->pixel_encoding = PIXEL_ENCODING_YCBCR420; else if ((connector->display_info.color_formats & DRM_COLOR_FORMAT_YCBCR422) - && stream->signal == SIGNAL_TYPE_HDMI_TYPE_A) + && aconnector + && aconnector->force_yuv422_output) timing_out->pixel_encoding = PIXEL_ENCODING_YCBCR422; else if ((connector->display_info.color_formats & DRM_COLOR_FORMAT_YCBCR444) && stream->signal == SIGNAL_TYPE_HDMI_TYPE_A) @@ -7665,6 +7666,7 @@ create_validate_stream_for_sink(struct drm_connector *connector, bpc_limit = 8;
do { + drm_dbg_kms(connector->dev, "Trying with %d bpc\n", requested_bpc); stream = create_stream_for_sink(connector, drm_mode, dm_state, old_stream, requested_bpc); @@ -7700,16 +7702,41 @@ create_validate_stream_for_sink(struct drm_connector *connector,
} while (stream == NULL && requested_bpc >= bpc_limit);
- if ((dc_result == DC_FAIL_ENC_VALIDATE || - dc_result == DC_EXCEED_DONGLE_CAP) && - !aconnector->force_yuv420_output) { - DRM_DEBUG_KMS("%s:%d Retry forcing yuv420 encoding\n", - __func__, __LINE__); - - aconnector->force_yuv420_output = true; + switch (dc_result) { + /* + * If we failed to validate DP bandwidth stream with the requested RGB color depth, + * we try to fallback and configure in order: + * YUV422 (8bpc, 6bpc) + * YUV420 (8bpc, 6bpc) + */ + case DC_FAIL_ENC_VALIDATE: + case DC_EXCEED_DONGLE_CAP: + case DC_NO_DP_LINK_BANDWIDTH: + /* recursively entered twice and already tried both YUV422 and YUV420 */ + if (aconnector->force_yuv422_output && aconnector->force_yuv420_output) + break; + /* first failure; try YUV422 */ + if (!aconnector->force_yuv422_output) { + drm_dbg_kms(connector->dev, "%s:%d Validation failed with %d, retrying w/ YUV422\n", + __func__, __LINE__, dc_result); + aconnector->force_yuv422_output = true; + /* recursively entered and YUV422 failed, try YUV420 */ + } else if (!aconnector->force_yuv420_output) { + drm_dbg_kms(connector->dev, "%s:%d Validation failed with %d, retrying w/ YUV420\n", + __func__, __LINE__, dc_result); + aconnector->force_yuv420_output = true; + } stream = create_validate_stream_for_sink(connector, drm_mode, - dm_state, old_stream); + dm_state, old_stream); + aconnector->force_yuv422_output = false; aconnector->force_yuv420_output = false; + break; + case DC_OK: + break; + default: + drm_dbg_kms(connector->dev, "%s:%d Unhandled validation failure %d\n", + __func__, __LINE__, dc_result); + break; }
return stream; diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h index 42801caf57b69..bb0ed81bcacdf 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.h @@ -790,6 +790,7 @@ struct amdgpu_dm_connector {
bool fake_enable; bool force_yuv420_output; + bool force_yuv422_output; struct dsc_preferred_settings dsc_settings; union dp_downstream_port_present mst_downstream_port_present; /* Cached display modes */