From 8b7078d1bbd8bb548cc97d5214adb828e9f0037c Mon Sep 17 00:00:00 2001 From: Dave Stevenson Date: Thu, 26 Oct 2023 18:23:31 +0100 Subject: [PATCH] drm/vc4: Free all stale dlists if channel is disabled The code handling freeing stale dlists had 2 issues: - it disabled the interrupt as soon as the first EOF interrupt occurred, even if it didn't clear all stale allocations, thus leading to stale entries - It didn't free stale entries from disabled channels, so eg "kmstest -c 0" could leave a stale alloc on channel 1 floating around. Keep the interrupt enabled whilst there are any outstanding allocs, and discard those on disabled channels. This second channel does require us to call vc4_hvs_stop_channel from vc4_crtc_atomic_disable so that the channel actually gets stopped. Signed-off-by: Dave Stevenson --- drivers/gpu/drm/vc4/vc4_crtc.c | 2 ++ drivers/gpu/drm/vc4/vc4_hvs.c | 27 +++++++++++++++++++++++++-- 2 files changed, 27 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/vc4/vc4_crtc.c +++ b/drivers/gpu/drm/vc4/vc4_crtc.c @@ -660,6 +660,8 @@ static void vc4_crtc_atomic_disable(stru vc4_crtc_disable(crtc, encoder, state, old_vc4_state->assigned_channel); + vc4_hvs_atomic_disable(crtc, state); + /* * Make sure we issue a vblank event after disabling the CRTC if * someone was waiting it. --- a/drivers/gpu/drm/vc4/vc4_hvs.c +++ b/drivers/gpu/drm/vc4/vc4_hvs.c @@ -697,7 +697,8 @@ static void vc4_hvs_schedule_dlist_sweep if (!list_empty(&hvs->stale_dlist_entries)) queue_work(system_unbound_wq, &hvs->free_dlist_work); - vc4_hvs_irq_clear_eof(hvs, channel); + if (list_empty(&hvs->stale_dlist_entries)) + vc4_hvs_irq_clear_eof(hvs, channel); spin_unlock_irqrestore(&hvs->mm_lock, flags); } @@ -712,6 +713,27 @@ static bool vc4_hvs_frcnt_lte(u8 cnt1, u return (s8)((cnt1 << 2) - (cnt2 << 2)) <= 0; } +bool vc4_hvs_check_channel_active(struct vc4_hvs *hvs, unsigned int fifo) +{ + struct vc4_dev *vc4 = hvs->vc4; + struct drm_device *drm = &vc4->base; + bool enabled = false; + int idx; + + WARN_ON_ONCE(vc4->gen > VC4_GEN_6); + + if (!drm_dev_enter(drm, &idx)) + return 0; + + if (vc4->gen >= VC4_GEN_6) + enabled = HVS_READ(SCALER6_DISPX_CTRL0(fifo)) & SCALER6_DISPX_CTRL0_ENB; + else + enabled = HVS_READ(SCALER_DISPCTRLX(fifo)) & SCALER_DISPCTRLX_ENABLE; + + drm_dev_exit(idx); + return enabled; +} + /* * Some atomic commits (legacy cursor updates, mostly) will not wait for * the next vblank and will just return once the commit has been pushed @@ -746,7 +768,8 @@ static void vc4_hvs_dlist_free_work(stru u8 frcnt; frcnt = vc4_hvs_get_fifo_frame_count(hvs, cur->channel); - if (!vc4_hvs_frcnt_lte(cur->target_frame_count, frcnt)) + if (vc4_hvs_check_channel_active(hvs, cur->channel) && + !vc4_hvs_frcnt_lte(cur->target_frame_count, frcnt)) continue; vc4_hvs_free_dlist_entry_locked(hvs, cur);