From: Leo Li Date: Thu, 5 Sep 2024 22:45:04 +0000 (-0400) Subject: drm/amd/display: Do not reset planes based on crtc zpos_changed X-Git-Url: https://git.dujemihanovic.xyz/?a=commitdiff_plain;h=578aab4ecc73476393389440724b7a391cc0cea9;p=linux.git drm/amd/display: Do not reset planes based on crtc zpos_changed [Why] drm_normalize_zpos will set the crtc_state->zpos_changed to 1 if any of it's assigned planes changes zpos, or is removed/added from it. To have amdgpu_dm request a plane reset on this is too broad. For example, if only the cursor plane was moved from one crtc to another, the crtc's zpos_changed will be set to true. But that does not mean that the underlying primary plane requires a reset. [How] Narrow it down so that only the plane that has a change in zpos will require a reset. As a future TODO, we can further optimize this by only requiring a reset on z-order change. Z-order is different from z-pos, since a zpos change doesn't necessarily mean the z-ordering changed, and DC should only require a reset if the z-ordering changed. For example, the following zpos update does not change z-ordering: Plane A: zpos 2 -> 3 Plane B: zpos 1 -> 2 => Plane A is still on top of plane B: no reset needed Whereas this one does change z-ordering: Plane A: zpos 2 -> 1 Plane B: zpos 1 -> 2 => Plane A changed from on top, to below plane B: reset needed Fixes: 38e0c3df6dbd ("drm/amd/display: Move PRIMARY plane zpos higher") Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3569 Signed-off-by: Leo Li Reviewed-by: Harry Wentland Signed-off-by: Alex Deucher --- 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 ae293ca69809..2a2b789917fc 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -10561,7 +10561,7 @@ static bool should_reset_plane(struct drm_atomic_state *state, * TODO: We can likely skip bandwidth validation if the only thing that * changed about the plane was it'z z-ordering. */ - if (new_crtc_state->zpos_changed) + if (old_plane_state->normalized_zpos != new_plane_state->normalized_zpos) return true; if (drm_atomic_crtc_needs_modeset(new_crtc_state))