On Thu, Oct 30, 2025 at 4:16 PM Mario Limonciello (AMD) <[email protected]> wrote: > > commit 978fa2f6d0b12 ("drm/amd/display: Use scaling for non-native > resolutions on eDP") started using the GPU scaler hardware to scale > when a non-native resolution was picked on eDP. This scaling was done > to fill the screen instead of maintain aspect ratio. > > The idea was supposed to be that if a different scaling behavior is > preferred then the compositor would request it. The not following > aspect ratio behavior however isn't desirable, so adjust it to follow > aspect ratio and still try to fill screen. > > Note: This will lead to black bars in some cases for non-native > resolutions. Compositors can request the previous behavior if desired. >
We may end up getting bug reports about the black bars. We had a similar debate about what the right default was for radeon 15 years ago. That said, at least with this the pixels will be square with this patch. Acked-by: Alex Deucher <[email protected]> > Fixes: 978fa2f6d0b12 ("drm/amd/display: Use scaling for non-native > resolutions on eDP") > Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4538 > Signed-off-by: Mario Limonciello (AMD) <[email protected]> > --- > 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 29b9197bbbc32..5b279182e66a8 100644 > --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c > +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c > @@ -8078,7 +8078,7 @@ static int dm_encoder_helper_atomic_check(struct > drm_encoder *encoder, > "mode %dx%d@%dHz is not native, > enabling scaling\n", > adjusted_mode->hdisplay, > adjusted_mode->vdisplay, > drm_mode_vrefresh(adjusted_mode)); > - dm_new_connector_state->scaling = RMX_FULL; > + dm_new_connector_state->scaling = RMX_ASPECT; > } > return 0; > } > -- > 2.43.0 >
