The flag will need to be accessed atomically in the vblank interrupt handler, memory barriers won't be enough.
Signed-off-by: Laurent Pinchart laurent.pinchart@ideasonboard.com --- drivers/gpu/drm/omapdrm/omap_crtc.c | 28 +++++++++++++++++++++------- 1 file changed, 21 insertions(+), 7 deletions(-)
diff --git a/drivers/gpu/drm/omapdrm/omap_crtc.c b/drivers/gpu/drm/omapdrm/omap_crtc.c index c4877d626577..c83e836dfa29 100644 --- a/drivers/gpu/drm/omapdrm/omap_crtc.c +++ b/drivers/gpu/drm/omapdrm/omap_crtc.c @@ -68,6 +68,19 @@ enum omap_channel omap_crtc_channel(struct drm_crtc *crtc) return omap_crtc->channel; }
+static bool omap_crtc_is_pending(struct drm_crtc *crtc) +{ + struct omap_crtc *omap_crtc = to_omap_crtc(crtc); + unsigned long flags; + bool pending; + + spin_lock_irqsave(&crtc->dev->event_lock, flags); + pending = omap_crtc->pending; + spin_unlock_irqrestore(&crtc->dev->event_lock, flags); + + return pending; +} + int omap_crtc_wait_pending(struct drm_crtc *crtc) { struct omap_crtc *omap_crtc = to_omap_crtc(crtc); @@ -77,7 +90,7 @@ int omap_crtc_wait_pending(struct drm_crtc *crtc) * a single frame refresh even on slower displays. */ return wait_event_timeout(omap_crtc->pending_wait, - !omap_crtc->pending, + !omap_crtc_is_pending(crtc), msecs_to_jiffies(250)); }
@@ -294,6 +307,7 @@ static void omap_crtc_vblank_irq(struct omap_drm_irq *irq, uint32_t irqstatus) struct omap_crtc *omap_crtc = container_of(irq, struct omap_crtc, vblank_irq); struct drm_device *dev = omap_crtc->base.dev; + struct drm_crtc *crtc = &omap_crtc->base;
if (dispc_mgr_go_busy(omap_crtc->channel)) return; @@ -302,10 +316,10 @@ static void omap_crtc_vblank_irq(struct omap_drm_irq *irq, uint32_t irqstatus)
__omap_irq_unregister(dev, &omap_crtc->vblank_irq);
- rmb(); + spin_lock(&crtc->dev->event_lock); WARN_ON(!omap_crtc->pending); omap_crtc->pending = false; - wmb(); + spin_unlock(&crtc->dev->event_lock);
/* wake up userspace */ omap_crtc_complete_page_flip(&omap_crtc->base); @@ -337,10 +351,10 @@ static void omap_crtc_enable(struct drm_crtc *crtc)
DBG("%s", omap_crtc->name);
- rmb(); + spin_lock_irq(&crtc->dev->event_lock); WARN_ON(omap_crtc->pending); omap_crtc->pending = true; - wmb(); + spin_unlock_irq(&crtc->dev->event_lock);
omap_irq_register(crtc->dev, &omap_crtc->vblank_irq);
@@ -406,10 +420,10 @@ static void omap_crtc_atomic_flush(struct drm_crtc *crtc,
DBG("%s: GO", omap_crtc->name);
- rmb(); + spin_lock_irq(&crtc->dev->event_lock); WARN_ON(omap_crtc->pending); omap_crtc->pending = true; - wmb(); + spin_unlock_irq(&crtc->dev->event_lock);
dispc_mgr_go(omap_crtc->channel); omap_irq_register(crtc->dev, &omap_crtc->vblank_irq);