From de3f440f8c9922afe8770dd16c84f1c87d779b59 Mon Sep 17 00:00:00 2001 From: Jesse Barnes Date: Thu, 14 Jan 2010 13:18:02 -0800 Subject: [PATCH] drm/i915: handle non-flip pending case when unpinning the scanout buffer The first page flip queued will replace the current front buffer, which should have a 0 pending flip count. So at finish time we need to handle that case (i.e. if the flip count is 0 *or* dec_and_test is 0 we need to wake the waiters). Also fix up an error path in the queue function and add some debug output (only enabled with driver debugging). Signed-off-by: Jesse Barnes Signed-off-by: Eric Anholt --- drivers/gpu/drm/i915/intel_display.c | 20 ++++++++++++++++++-- 1 file changed, 18 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 2cc489b6629..5f14dfbf715 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -3985,6 +3985,12 @@ void intel_finish_page_flip(struct drm_device *dev, int pipe) spin_lock_irqsave(&dev->event_lock, flags); work = intel_crtc->unpin_work; if (work == NULL || !work->pending) { + if (work && !work->pending) { + obj_priv = work->obj->driver_private; + DRM_DEBUG_DRIVER("flip finish: %p (%d) not pending?\n", + obj_priv, + atomic_read(&obj_priv->pending_flip)); + } spin_unlock_irqrestore(&dev->event_lock, flags); return; } @@ -4006,7 +4012,10 @@ void intel_finish_page_flip(struct drm_device *dev, int pipe) spin_unlock_irqrestore(&dev->event_lock, flags); obj_priv = work->obj->driver_private; - if (atomic_dec_and_test(&obj_priv->pending_flip)) + + /* Initial scanout buffer will have a 0 pending flip count */ + if ((atomic_read(&obj_priv->pending_flip) == 0) || + atomic_dec_and_test(&obj_priv->pending_flip)) DRM_WAKEUP(&dev_priv->pending_flip_queue); schedule_work(&work->work); } @@ -4019,8 +4028,11 @@ void intel_prepare_page_flip(struct drm_device *dev, int plane) unsigned long flags; spin_lock_irqsave(&dev->event_lock, flags); - if (intel_crtc->unpin_work) + if (intel_crtc->unpin_work) { intel_crtc->unpin_work->pending = 1; + } else { + DRM_DEBUG_DRIVER("preparing flip with no unpin work?\n"); + } spin_unlock_irqrestore(&dev->event_lock, flags); } @@ -4054,6 +4066,7 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc, /* We borrow the event spin lock for protecting unpin_work */ spin_lock_irqsave(&dev->event_lock, flags); if (intel_crtc->unpin_work) { + DRM_DEBUG_DRIVER("flip queue: crtc already busy\n"); spin_unlock_irqrestore(&dev->event_lock, flags); kfree(work); mutex_unlock(&dev->struct_mutex); @@ -4067,7 +4080,10 @@ static int intel_crtc_page_flip(struct drm_crtc *crtc, ret = intel_pin_and_fence_fb_obj(dev, obj); if (ret != 0) { + DRM_DEBUG_DRIVER("flip queue: %p pin & fence failed\n", + obj->driver_private); kfree(work); + intel_crtc->unpin_work = NULL; mutex_unlock(&dev->struct_mutex); return ret; } -- 2.39.3