[Intel-gfx] [PATCH] drm/irq: Even more debug output for drm_wait_one_vblank

[Daniel Vetter]

We have a bit of fun with vblank waits not working correctly right
away after enabling a crtc, so let's add more debug output to figure
what's going on.

References: https://bugs.freedesktop.org/show_bug.cgi?id=84162
Signed-off-by: Daniel Vetter <daniel.vetter at intel.com>
---
 drivers/gpu/drm/drm_irq.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index 5ef03c216a27..5b5c32a08a45 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -1086,7 +1086,9 @@ void drm_wait_one_vblank(struct drm_device *dev, int crtc)
 				 last != drm_vblank_count(dev, crtc),
 				 msecs_to_jiffies(100));
 
-	WARN(ret == 0, "vblank wait timed out on crtc %i\n", crtc);
+	WARN(ret == 0,
+	     "vblank wait timed out on crtc %i, last: %u, current %u\n",
+	     crtc, last, drm_vblank_count(dev, crtc));
 
 	drm_vblank_put(dev, crtc);
 }
-- 
1.9.3