tree 222aeb2a501ddd82c5ec0877fd09ccc0c851c552
parent 832afda6a7d7235ef0e09f4ec46736861540da6d
author Daniel Vetter <daniel.vetter@ffwll.ch> 1322416697 +0100
committer Keith Packard <keithp@keithp.com> 1324350948 -0800

drm/i915: check ACTHD of all rings

Otherwise hangcheck spuriously fires when running blitter/bsd-only
workloads.

Contrary to a similar patch by Ben Widawsky this does not check
INSTDONE of the other rings. Chris Wilson implied that in a failure to
detect a hang, most likely because INSTDONE was fluctuating. Thus only
check ACTHD, which as far as I know is rather reliable. Also, blitter
and bsd rings can't launch complex tasks from a single instruction
(like 3D_PRIM on the render with complex or even infinite shaders).

This fixes spurious gpu hang detection when running
tests/gem_hangcheck_forcewake on snb/ivb.

Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Keith Packard <keithp@keithp.com>