On Fri, Sep 26, 2025 at 2:26 PM Timur Kristóf <[email protected]> wrote: > > 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. > > Signed-off-by: Timur Kristóf <[email protected]>
Reviewed-by: Alex Deucher <[email protected]> > --- > 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 cf9932e68055..3a9522c17fee 100644 > --- a/drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c > +++ b/drivers/gpu/drm/amd/pm/legacy-dpm/si_dpm.c > @@ -3500,6 +3500,11 @@ 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. > -- > 2.51.0 >
