On 2026. augusztus 19., szerda 9:27:20 közép-európai nyári idő Michel Dänzer wrote: > [ Adding Timur ]
Thank you for your consideration! > > On 8/18/26 22:14, [email protected] wrote: > > From: James Lin <[email protected]> > > > > [why] > > amdgpu_dm_crtc_get_cursor_mode() returns DM_CURSOR_NATIVE_MODE early and > > unconditionally for dcn4.x. That early return was added because these > > ASICs no longer have the cursor-on-scaled-plane or cursor-on-yuv-plane > > restrictions of older DCN, so native cursor is fine in those cases. > > However, it also bypasses the "does the top plane fill the CRTC?" (hole) > > evaluation further down. When the top/primary plane does not cover the > > whole CRTC, the cursor must fall back to an overlay plane so it is > > composited over the uncovered region; keeping the native cursor there > > produces an incorrect result. As a consequence > > igt@amdgpu/amd_cursor_overlay@non-full, which verifies exactly this > > native->overlay fallback, fails on dcn42. > > > > [how] > > Change unconditional early return with a skip_fmt_scale_restrictions flag. > > For dcn4.x keep skipping the YUV / active-color-pipeline / different-scale > > overlay triggers (genuinely unnecessary on this hardware), but fall > > through to the existing entire_crtc_covered check so a top plane that does > > not fill the CRTC still selects DM_CURSOR_OVERLAY_MODE. Native mode is > > still chosen when the plane covers the whole CRTC. > > > > Update the amdgpu_dm_cursor KUnit tests accordingly: exercise the dcn4x > > path with a full atomic state fixture (full coverage -> native) and add a > > dcn4x hole case (top plane does not fill the CRTC -> overlay). > > > > Reviewed-by: Tom Chung <[email protected]> > > Signed-off-by: James Lin <[email protected]> > > Signed-off-by: Ivan Lipski <[email protected]> > > --- > > > > .../amd/display/amdgpu_dm/amdgpu_dm_cursor.c | 28 ++++++++-------- > > .../amdgpu_dm/tests/amdgpu_dm_cursor_test.c | 32 +++++++++++++------ > > 2 files changed, 38 insertions(+), 22 deletions(-) > > > > diff --git a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_cursor.c > > b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_cursor.c index > > 9534848ed240c..c41fce07b8fa8 100644 > > --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_cursor.c > > +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm_cursor.c > > [...] > > @@ -300,15 +297,17 @@ int amdgpu_dm_crtc_get_cursor_mode(struct > > amdgpu_device *adev,> > > */ > > > > if (amdgpu_ip_version(adev, DCE_HWIP, 0) == IP_VERSION(4, 0, 1) || > > > > amdgpu_ip_version(adev, DCE_HWIP, 0) == IP_VERSION(4, 2, 0) || > > > > -#if defined(CONFIG_DRM_AMD_DC_DCN6_0) > > > > amdgpu_ip_version(adev, DCE_HWIP, 0) == IP_VERSION(4, 2, 1) || > > amdgpu_ip_version(adev, DCE_HWIP, 0) == IP_VERSION(6, 0, 0) || > > > > -#else > > - amdgpu_ip_version(adev, DCE_HWIP, 0) == IP_VERSION(4, 2, 1) || > > -#endif > > > > !dm_crtc_state->base.enable) { > > > > - *cursor_mode = DM_CURSOR_NATIVE_MODE; > > - return 0; > > + /* > > + * Newer DCN has no cursor-on-scaled/yuv-plane restriction, so > > + * skip those overlay triggers below. A plane that does not fill > > + * the CRTC still needs overlay mode so the cursor renders over > > + * the hole, so fall through to the coverage check instead of > > + * unconditionally forcing native mode here. > > + */ > > + skip_fmt_scale_restrictions = true; > > > > } > > Timur, looks like this might break your fix in cea54c52d82d > ("drm/amd/display: Set native cursor mode for disabled CRTCs") again. > > Maybe the CRTC disabled case should be handled separately from the DCE cases > after all. I think the cleanest solution may be to just move this check: !dm_crtc_state->base.enable into a separate if statement above this one. What do you think, would that fix it? Thanks, Timur
