From: Daniel Vetter daniel.vetter@ffwll.ch
[ Upstream commit ec3d65082d7dabad6fa8f66a8ef166f2d522d6b2 ]
Per at least one tester this is enough magic to recover the regression introduced for some people (but not all) in
commit b8e2b0199cc377617dc238f5106352c06dcd3fa2 Author: Peter Rosin peda@axentia.se Date: Tue Jul 4 12:36:57 2017 +0200
drm/fb-helper: factor out pseudo-palette
which for radeon had the side-effect of refactoring out a seemingly redudant writing of the color palette.
10ms in a fairly slow modeset path feels like an acceptable form of duct-tape, so maybe worth a shot and see what sticks.
Cc: Alex Deucher alexander.deucher@amd.com Cc: Michel Dänzer michel.daenzer@amd.com References: https://bugzilla.kernel.org/show_bug.cgi?id=198123 Signed-off-by: Daniel Vetter daniel.vetter@intel.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/radeon/radeon_display.c | 2 ++ 1 file changed, 2 insertions(+)
diff --git a/drivers/gpu/drm/radeon/radeon_display.c b/drivers/gpu/drm/radeon/radeon_display.c index 84d3d885b7a46..606972c4593aa 100644 --- a/drivers/gpu/drm/radeon/radeon_display.c +++ b/drivers/gpu/drm/radeon/radeon_display.c @@ -127,6 +127,8 @@ static void dce5_crtc_load_lut(struct drm_crtc *crtc)
DRM_DEBUG_KMS("%d\n", radeon_crtc->crtc_id);
+ msleep(10); + WREG32(NI_INPUT_CSC_CONTROL + radeon_crtc->crtc_offset, (NI_INPUT_CSC_GRPH_MODE(NI_INPUT_CSC_BYPASS) | NI_INPUT_CSC_OVL_MODE(NI_INPUT_CSC_BYPASS)));