6.6-stable review patch. If anyone has any objections, please let me know.
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From: Timur Kristóf timur.kristof@gmail.com
[ Upstream commit 5c05bcf6ae7732da1bd4dc1958d527b5f07f216a ]
On various SI GPUs, a flickering can be observed near the bottom edge of the screen when using a single 4K 60Hz monitor over DP. Disabling MCLK switching works around this problem.
Reviewed-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Timur Kristóf timur.kristof@gmail.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c b/drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c index 2863dc65ffc6f..e5f68b2b8def3 100644 --- a/drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c +++ b/drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c @@ -3485,6 +3485,11 @@ static void si_apply_state_adjust_rules(struct amdgpu_device *adev, * for these GPUs to calculate bandwidth requirements. */ if (high_pixelclock_count) { + /* Work around flickering lines at the bottom edge + * of the screen when using a single 4K 60Hz monitor. + */ + disable_mclk_switching = true; + /* On Oland, we observe some flickering when two 4K 60Hz * displays are connected, possibly because voltage is too low. * Raise the voltage by requiring a higher SCLK.