From: Melissa Wen mwen@igalia.com
commit 0e444a4de6b38c4593a07e4cfb5bf54c40cc79b6 upstream.
DM maps DRM CRTC degamma to DPP (pre-blending) degamma block, but DCE doesn't support programmable degamma curve anywhere. Currently, a custom degamma is accepted by DM but just ignored by DCE driver and degamma correction isn't actually applied. There is no way to map custom degamma in DCE, therefore, DRM CRTC degamma property shouldn't be enabled for DCE drivers.
Reviewed-by: Rodrigo Siqueira Rodrigo.Siqueira@amd.com Signed-off-by: Melissa Wen mwen@igalia.com Signed-off-by: Rodrigo Siqueira Rodrigo.Siqueira@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Cc: stable@vger.kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)
--- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_crtc.c @@ -412,7 +412,7 @@ int amdgpu_dm_crtc_init(struct amdgpu_di { struct amdgpu_crtc *acrtc = NULL; struct drm_plane *cursor_plane; - + bool is_dcn; int res = -ENOMEM;
cursor_plane = kzalloc(sizeof(*cursor_plane), GFP_KERNEL); @@ -450,8 +450,14 @@ int amdgpu_dm_crtc_init(struct amdgpu_di acrtc->otg_inst = -1;
dm->adev->mode_info.crtcs[crtc_index] = acrtc; - drm_crtc_enable_color_mgmt(&acrtc->base, MAX_COLOR_LUT_ENTRIES, + + /* Don't enable DRM CRTC degamma property for DCE since it doesn't + * support programmable degamma anywhere. + */ + is_dcn = dm->adev->dm.dc->caps.color.dpp.dcn_arch; + drm_crtc_enable_color_mgmt(&acrtc->base, is_dcn ? MAX_COLOR_LUT_ENTRIES : 0, true, MAX_COLOR_LUT_ENTRIES); + drm_mode_crtc_set_gamma_size(&acrtc->base, MAX_COLOR_LEGACY_LUT_ENTRIES);
return 0;