drm/amd/display: Always get CRTC updated constant values inside commit tail
We recently improved our display atomic commit and tail sequence to avoid some issues related to concurrency. One of the major changes consisted of moving the interrupt disable and the stream release from our atomic commit to our atomic tail (commit 6d90a208 ("drm/amd/display: Move disable interrupt into commit tail")) . However, the new code introduced inside our commit tail function was inserted right after the function drm_atomic_helper_update_legacy_modeset_state(), which has routines for updating internal data structs related to timestamps. As a result, in certain conditions, the display module can reach a situation where we update our constants and, after that, clean it. This situation generates the following warning: amdgpu 0000:03:00.0: drm_WARN_ON_ONCE(drm_drv_uses_atomic_modeset(dev)) WARNING: CPU: 6 PID: 1269 at drivers/gpu/drm/drm_vblank.c:722 drm_crtc_vblank_helper_get_vblank_timestamp_internal+0x32b/0x340 [drm] ... RIP: 0010:drm_crtc_vblank_helper_get_vblank_timestamp_internal+0x32b/0x340 [drm] ... Call Trace: ? dc_stream_get_vblank_counter+0x57/0x60 [amdgpu] drm_crtc_vblank_helper_get_vblank_timestamp+0x1c/0x20 [drm] drm_get_last_vbltimestamp+0xad/0xc0 [drm] drm_reset_vblank_timestamp+0x63/0xd0 [drm] drm_crtc_vblank_on+0x85/0x150 [drm] amdgpu_dm_atomic_commit_tail+0xaf1/0x2330 [amdgpu] commit_tail+0x99/0x130 [drm_kms_helper] drm_atomic_helper_commit+0x123/0x150 [drm_kms_helper] amdgpu_dm_atomic_commit+0x11/0x20 [amdgpu] drm_atomic_commit+0x4a/0x50 [drm] drm_atomic_helper_set_config+0x7c/0xc0 [drm_kms_helper] drm_mode_setcrtc+0x20b/0x7e0 [drm] ? tomoyo_path_number_perm+0x6f/0x200 ? drm_mode_getcrtc+0x190/0x190 [drm] drm_ioctl_kernel+0xae/0xf0 [drm] drm_ioctl+0x245/0x400 [drm] ? drm_mode_getcrtc+0x190/0x190 [drm] amdgpu_drm_ioctl+0x4e/0x80 [amdgpu] __x64_sys_ioctl+0x91/0xc0 do_syscall_64+0x38/0x90 entry_SYSCALL_64_after_hwframe+0x44/0xa9 ... For fixing this issue we rely upon a refactor introduced on drm_atomic_helper_update_legacy_modeset_state ("Remove the timestamping constant update from drm_atomic_helper_update_legacy_modeset_state()") which decouples constant values update from drm_atomic_helper_update_legacy_modeset_state to a new helper. Basically, this commit uses this new helper and place it right after our release module to avoid a situation where our CRTC struct gets wrong values. Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1373 Bug: https://gitlab.freedesktop.org/drm/amd/-/issues/1349 Reviewed-by: Harry Wentland <harry.wentland@amd.com> Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
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