From cf37a5318dd68aa0eb909e210aebd219bc0ff64a Mon Sep 17 00:00:00 2001 From: Agustin Gutierrez Date: Thu, 25 Apr 2024 10:37:36 -0400 Subject: [PATCH] drm/amd/display: MST DSC check for older devices [Why] Some older MST hubs do not report DPCD registers according to specification. [How] This change re-applies commit c53655545141 ("drm/amd/display: dsc mst re-compute pbn for changes on hub"). With an additional check for these older MST devices. Reviewed-by: Swapnil Patel Acked-by: Tom Chung Signed-off-by: Agustin Gutierrez Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher --- .../amd/display/amdgpu_dm/amdgpu_dm_mst_types.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c index f0322e730214b..cb31a699c6622 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_mst_types.c @@ -1219,6 +1219,12 @@ static bool is_dsc_need_re_compute( if (dc_link->type != dc_connection_mst_branch) return false; + /* add a check for older MST DSC with no virtual DPCDs */ + if (needs_dsc_aux_workaround(dc_link) && + (!(dc_link->dpcd_caps.dsc_caps.dsc_basic_caps.fields.dsc_support.DSC_SUPPORT || + dc_link->dpcd_caps.dsc_caps.dsc_basic_caps.fields.dsc_support.DSC_PASSTHROUGH_SUPPORT))) + return false; + for (i = 0; i < MAX_PIPES; i++) stream_on_link[i] = NULL; @@ -1240,12 +1246,8 @@ static bool is_dsc_need_re_compute( continue; /* - * Check if cached virtual MST DSC caps are available and DSC is supported - * this change takes care of newer MST DSC capable devices that report their - * DPCD caps as per specifications in their Virtual DPCD registers. - - * TODO: implement the check for older MST DSC devices that do not conform to - * specifications. + * check if cached virtual MST DSC caps are available and DSC is supported + * as per specifications in their Virtual DPCD registers. */ if (!(aconnector->dc_sink->dsc_caps.dsc_dec_caps.is_dsc_supported || aconnector->dc_link->dpcd_caps.dsc_caps.dsc_basic_caps.fields.dsc_support.DSC_PASSTHROUGH_SUPPORT)) -- 2.30.2