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| author |   Janne Grunau <j@jannau.net> | 2025-04-28 13:37:14 +0200 |
|---|---|---|
| committer |   Alyssa Rosenzweig <alyssa@rosenzweig.io> | 2025-04-28 14:17:52 -0400 |
| commit | 7a7d6681d5adde7dc7e648dcc6b9e9be6ca93d5d (patch) | |
| tree | cdd512f22609ca7c1110853bdad995813ebc73a3 | |
| parent | drm: adp: Use spin_lock_irqsave for drm device event_lock (diff) | |
| download | wireguard-linux-7a7d6681d5adde7dc7e648dcc6b9e9be6ca93d5d.tar.xz wireguard-linux-7a7d6681d5adde7dc7e648dcc6b9e9be6ca93d5d.zip | |
drm: adp: Handle drm_crtc_vblank_get() errors
drm_crtc_vblank_get() may fail when it's called before
drm_crtc_vblank_on() on a resetted CRTC. This occurs in
drm_crtc_helper_funcs' atomic_flush() calls after
drm_atomic_helper_crtc_reset() for example directly after probe. Send
the vblank event directly in such cases. Avoids following warning in
the subsequent drm_crtc_vblank_put() call from the vblank irq handler as
below:
adp 228200000.display-pipe: [drm] drm_WARN_ON(atomic_read(&vblank->refcount) == 0)
WARNING: CPU: 5 PID: 1206 at drivers/gpu/drm/drm_vblank.c:1247 drm_vblank_put+0x158/0x170
...
Call trace:
drm_vblank_put+0x158/0x170 (P)
drm_crtc_vblank_put+0x24/0x38
adp_fe_irq+0xd8/0xe8 [adpdrm]
__handle_irq_event_percpu+0x94/0x318
handle_irq_event+0x54/0xd0
handle_fasteoi_irq+0xa8/0x240
handle_irq_desc+0x3c/0x68
generic_handle_domain_irq+0x24/0x40
Modifying `crtc->state->event` here is fine as crtc->mutex is locked by
the non-async atomic commit. In retrospect this looks so obvious that it
doesn't warrant a comment in the file.
Signed-off-by: Janne Grunau <j@jannau.net>
Reviewed-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Link: https://lore.kernel.org/r/20250428-drm_adp_fixes-v2-2-912e081e55d8@jannau.net
Signed-off-by: Alyssa Rosenzweig <alyssa@rosenzweig.io>
Diffstat (limited to '')
| -rw-r--r-- | drivers/gpu/drm/adp/adp_drv.c | 16 |
1 files changed, 11 insertions, 5 deletions
diff --git a/drivers/gpu/drm/adp/adp_drv.c b/drivers/gpu/drm/adp/adp_drv.c index 157298a8ff42..bdf27ee742ea 100644 --- a/drivers/gpu/drm/adp/adp_drv.c +++ b/drivers/gpu/drm/adp/adp_drv.c @@ -331,13 +331,19 @@ static void adp_crtc_atomic_flush(struct drm_crtc *crtc, } writel(ADBE_FIFO_SYNC | frame_num, adp->be + ADBE_FIFO); //FIXME: use adbe flush interrupt - spin_lock_irqsave(&crtc->dev->event_lock, flags); if (crtc->state->event) { - drm_crtc_vblank_get(crtc); - adp->event = crtc->state->event; + struct drm_pending_vblank_event *event = crtc->state->event; + + crtc->state->event = NULL; + spin_lock_irqsave(&crtc->dev->event_lock, flags); + + if (drm_crtc_vblank_get(crtc) != 0) + drm_crtc_send_vblank_event(crtc, event); + else + adp->event = event; + + spin_unlock_irqrestore(&crtc->dev->event_lock, flags); } - crtc->state->event = NULL; - spin_unlock_irqrestore(&crtc->dev->event_lock, flags); } static const struct drm_crtc_funcs adp_crtc_funcs = { |