From: Daniel Vetter <daniel.vetter@ffwll.ch>
Date: Mon, 15 Sep 2014 12:04:28 +0000 (+0200)
Subject: drm: Improve debug output for drm_wait_one_vblank
X-Git-Tag: v3.18-rc1~44^2~7^2~10
X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=80c873b6b7b4de56d0771e3834ea71467937e506;p=linux.git

drm: Improve debug output for drm_wait_one_vblank

This replicates what we've done in i915 in

commit 31e4b89acbd7b19c9a8557e6e660a583a0b97daa
Author: Damien Lespiau <damien.lespiau@intel.com>
Date:   Mon Aug 18 13:51:00 2014 +0100

    drm/i915: Print the pipe on which the vblank wait times out

to make sure that when we switch i915 to drm_wait_one_vblank that the
debug output doesn't regress.

Cc: Damien Lespiau <damien.lespiau@intel.com>
Cc: Thomas Wood <thomas.wood@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
---

diff --git a/drivers/gpu/drm/drm_irq.c b/drivers/gpu/drm/drm_irq.c
index e73cbdaa18df..5ef03c216a27 100644
--- a/drivers/gpu/drm/drm_irq.c
+++ b/drivers/gpu/drm/drm_irq.c
@@ -1077,7 +1077,7 @@ void drm_wait_one_vblank(struct drm_device *dev, int crtc)
 	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);
@@ -1086,7 +1086,7 @@ void drm_wait_one_vblank(struct drm_device *dev, int 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);
 }