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[0810/1094] drm/i915: Work-around garbage DR4 from UXA

Message ID 1413889294-31328-811-git-send-email-dheerajx.s.jamwal@intel.com (mailing list archive)
State New, archived
Headers show

Commit Message

Dheeraj Jamwal Oct. 21, 2014, 10:56 a.m. UTC 
From: Daniel Vetter <daniel.vetter@ffwll.ch>

Somehow UXA submits a completely bogus DR4 value since essentially
forever. It was originally introduced in

commit bade7d7d2505a10a8a7d24b084aff9742e2d6d64
Author: Eric Anholt <eric@anholt.net>
Date:   Fri Jun 6 14:03:25 2008 -0700

    Use the DRM for submitting batchbuffers when available.

and dutifully copied around ever since. Since we want to keep the
general dirt catching around just special case the UXA value.

This regression was introduced in

commit 9cb346648d9c529eccc5c7f30093e82d37004e37
Author: Daniel Vetter <daniel.vetter@ffwll.ch>
Date:   Thu Apr 24 08:09:11 2014 +0200

    drm/i915: Catch dirt in unused execbuffer fields

Comment from Chris' review:

"To be fair, it is a sensible value if one supposes a Region style API to
cliprects. Under that API, DR[14] define the extents of the clip region,
and ((0,0), (0,0)) [DR1==DR4==0] would mean all clipped, do not draw
anything."

v2: Pimp commit message a bit and remove the double space.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=78494
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Jörg Otte <jrg.otte@gmail.com>
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
(cherry picked from commit ffd93f24800dfbf55e9a245884cbfd8e427fc210)

Signed-off-by: Dheeraj Jamwal <dheerajx.s.jamwal@intel.com>
---
 drivers/gpu/drm/i915/i915_gem_execbuffer.c |    5 +++++
 1 file changed, 5 insertions(+)
diff mbox

Patch

diff --git a/drivers/gpu/drm/i915/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
index 0939b51..9465ba5 100644
--- a/drivers/gpu/drm/i915/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/i915_gem_execbuffer.c
@@ -1205,6 +1205,11 @@  i915_gem_do_execbuffer(struct drm_device *dev, void *data,
 			goto pre_mutex_err;
 		}
 	} else {
+		if (args->DR4 == 0xffffffff) {
+			DRM_DEBUG("UXA submitting garbage DR4, fixing up\n");
+			args->DR4 = 0;
+		}
+
 		if (args->DR1 || args->DR4 || args->cliprects_ptr) {
 			DRM_DEBUG("0 cliprects but dirt in cliprects fields\n");
 			return -EINVAL;