From 8419331e64d92a8de5fc4feef0e305f201fb8b33 Mon Sep 17 00:00:00 2001 From: Leo Li Date: Tue, 28 Jul 2026 13:02:47 -0400 Subject: [PATCH] drm/amd/display: Exit idle optimizations before programming [Why] We need to exit PSR/IPS before programming. Before calling DC for programming in amdgpu_dm_commit_planes(), there's a vblank_control_workqueue flush. This waits for IPS and PSR exit. (See drm_vblank_on/off() > amdgpu_dm_crtc_set_vblank() --queue_work()-> amdgpu_dm_crtc_vblank_control_worker()) Prior to the tagged "Fixes:" change, drm_vblank_get() was called before the workqueue flush. This ordering ensures that PSR exit occurred before programming. After the "Fixes:" change, drm_vblank_get() is called after the workqueue flush, leading to programming while idle optimizations are still active. This can lead to incorrect flip_pending detection used by vblank event delivery. [How] Split the vblank_get() component of `dm_arm_vblank_event()` into `dm_arm_vblank_event_pre_programming()`, which is called before programming. Call it before the vblank_control_workqueue flush. Includes a drive-by cleanup of prepare_flip_isr(): the only caller is dm_arm_vblank_event() and it's simple enough to roll-in. v2: Fix checkpatch formatting warning on drm_arm_vblank_event_pre_programming() arg alignment. Fixes: 48ab86360af1 ("drm/amd/display: check GRPH_FLIP status before sending event") Cc: stable@vger.kernel.org Link: https://gitlab.freedesktop.org/drm/amd/-/work_items/4141#note_3583205 Link: https://gitlab.freedesktop.org/drm/amd/-/work_items/5527 Assisted-by: Codex:gpt-5.6-sol Assisted-by: Claude:opus-5 Suggested-by: David Weber Signed-off-by: Leo Li Reviewed-by: Mario Limonciello (AMD) Signed-off-by: Alex Deucher (cherry picked from commit 05984e29520a28c27f5a2388742c957a6a87ee7a) --- .../gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c | 78 +++++++++++-------- 1 file changed, 46 insertions(+), 32 deletions(-) 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 eaf19ec843e8..1820547b1dde 100644 --- a/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c +++ b/drivers/gpu/drm/amd/display/amdgpu_dm/amdgpu_dm.c @@ -9903,25 +9903,6 @@ static void remove_stream(struct amdgpu_device *adev, acrtc->enabled = false; } -static void prepare_flip_isr(struct amdgpu_crtc *acrtc) -{ - - assert_spin_locked(&acrtc->base.dev->event_lock); - WARN_ON(acrtc->event); - - acrtc->event = acrtc->base.state->event; - - /* Set the flip status */ - acrtc->pflip_status = AMDGPU_FLIP_SUBMITTED; - - /* Mark this event as consumed */ - acrtc->base.state->event = NULL; - - drm_dbg_state(acrtc->base.dev, - "crtc:%d, pflip_stat:AMDGPU_FLIP_SUBMITTED\n", - acrtc->crtc_id); -} - static void update_freesync_state_on_stream( struct amdgpu_display_manager *dm, struct dm_crtc_state *new_crtc_state, @@ -10274,17 +10255,47 @@ static void dm_arm_vblank_event(struct amdgpu_crtc *acrtc, return; if (pflip_update) { - drm_crtc_vblank_get(&acrtc->base); WARN_ON(acrtc->pflip_status != AMDGPU_FLIP_NONE); - /* Arm flip completion handling and event delivery after programming. */ - prepare_flip_isr(acrtc); + WARN_ON(acrtc->event); + + acrtc->pflip_status = AMDGPU_FLIP_SUBMITTED; + acrtc->event = acrtc->base.state->event; + acrtc->base.state->event = NULL; + + drm_dbg_state(acrtc->base.dev, + "crtc:%d, pflip_stat:AMDGPU_FLIP_SUBMITTED\n", + acrtc->crtc_id); } else if (cursor_update) { - drm_crtc_vblank_get(&acrtc->base); acrtc->event = acrtc->base.state->event; acrtc->base.state->event = NULL; } } +/** + * dm_arm_vblank_event_pre_programming - Prepare for programming + * @acrtc: The amdgpu CRTC to prepare + * @acrtc_state: The new CRTC state + * @pflip_update: Whether a page flip is being programmed + * @cursor_update: Whether a cursor update is being programmed + * + * Grab a reference on the vblank counter if a page flip or cursor update is to + * be programmed. Do this before programming so the HW is not in any + * idle-optimized state (such as PSR). + */ +static void dm_arm_vblank_event_pre_programming(struct amdgpu_crtc *acrtc, + struct dm_crtc_state *acrtc_state, + bool pflip_update, + bool cursor_update) +{ + assert_spin_locked(&acrtc->base.dev->event_lock); + + if (!acrtc->base.state->event || acrtc_state->active_planes == 0) + return; + + if (pflip_update || cursor_update) + drm_crtc_vblank_get(&acrtc->base); +} + static void amdgpu_dm_commit_planes(struct drm_atomic_commit *state, struct drm_device *dev, struct amdgpu_display_manager *dm, @@ -10550,16 +10561,19 @@ static void amdgpu_dm_commit_planes(struct drm_atomic_commit *state, } } - /* - * DCE depends on a combination of GRPH_FLIP, VLINE0, and VUPDATE for - * event delivery. Only GRPH_FLIP handler can send pflip events, and it - * only fires if HW latched to the flip. Maintain legacy behavior by - * arming event before programming. - */ - if (amdgpu_ip_version(dm->adev, DCE_HWIP, 0) == 0) { - scoped_guard(spinlock_irqsave, &pcrtc->dev->event_lock) { + scoped_guard(spinlock_irqsave, &pcrtc->dev->event_lock) { + dm_arm_vblank_event_pre_programming(acrtc_attach, acrtc_state, + pflip_present, + cursor_update); + /* + * DCE depends on a combination of GRPH_FLIP, VLINE0, and + * VUPDATE for event delivery. Only GRPH_FLIP handler can send + * pflip events, and it only fires if HW latched to the flip. + * Maintain legacy behavior by arming event before programming. + */ + if (amdgpu_ip_version(dm->adev, DCE_HWIP, 0) == 0) { dm_arm_vblank_event(acrtc_attach, acrtc_state, - pflip_present, cursor_update); + pflip_present, cursor_update); } } -- 2.47.3