This will let us pass the kms_hdr.bpc_switch IGT test. The reason the bpc restriction was required is historical. At one point in time we were not falling back to a lower bpc when we didn't have enough bandwidth for the maximum bpc reported by a display. This meant that we couldn't enable some high refresh modes unless we limitted the bpc. Starting with this patch the issue is fixed: cbd14ae7ea93 ("drm/amd/display: Fix incorrectly pruned modes with deep color") This patch implemented a fallback mechanism if mode validation failed at the max bpc. This means users now automatically get all modes that can be supported by at least 6 bpc. The driver will enable the mode with the highest possible bpc that is supported by the display. v2: - explain why this is no longer needed (Michel) - refer to commit that fixed bpc fallback (Michel) Signed-off-by: Harry Wentland <harry.wentland@xxxxxxx> Cc: Pekka Paalanen <ppaalanen@xxxxxxxxx> Cc: Sebastian Wick <sebastian.wick@xxxxxxxxxx> Cc: Vitaly.Prosyak@xxxxxxx Cc: Joshua Ashton <joshua@xxxxxxxxx> Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx Cc: amd-gfx@xxxxxxxxxxxxxxxxxxxxx Cc: Michel Dänzer <michel.daenzer@xxxxxxxxxxx> Reviewed-By: Joshua Ashton <joshua@xxxxxxxxx> Reviewed-by: Michel Dänzer <mdaenzer@xxxxxxxxxx> --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 2 +- 1 file changed, 1 insertion(+), 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 73a98e6e1867..f74b125af31f 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -7130,7 +7130,7 @@ void amdgpu_dm_connector_init_helper(struct amdgpu_display_manager *dm, drm_connector_attach_max_bpc_property(&aconnector->base, 8, 16); /* This defaults to the max in the range, but we want 8bpc for non-edp. */ - aconnector->base.state->max_bpc = (connector_type == DRM_MODE_CONNECTOR_eDP) ? 16 : 8; + aconnector->base.state->max_bpc = 16; aconnector->base.state->max_requested_bpc = aconnector->base.state->max_bpc; if (connector_type == DRM_MODE_CONNECTOR_eDP && -- 2.39.0