DRM_DEBUG("updating vblank count on crtc %d, missed %d\n",
crtc, diff);
+ if (diff == 0)
+ return;
+
/* Reinitialize corresponding vblank timestamp if high-precision query
* available. Skip this step if query unsupported or failed. Will
* reinitialize delayed at next vblank interrupt in that case.
u32 last;
ret = drm_vblank_get(dev, crtc);
- if (WARN_ON(ret))
+ if (WARN(ret, "vblank not available on crtc %i, ret=%i\n", crtc, ret))
return;
last = drm_vblank_count(dev, crtc);
last != drm_vblank_count(dev, crtc),
msecs_to_jiffies(100));
- WARN_ON(ret == 0);
+ WARN(ret == 0, "vblank wait timed out on crtc %i\n", crtc);
drm_vblank_put(dev, crtc);
}