drm/i915: enable forcewake voodoo also for gen6
authorDaniel Vetter <daniel.vetter@ffwll.ch>
Wed, 25 Jan 2012 13:04:00 +0000 (14:04 +0100)
committerDaniel Vetter <daniel.vetter@ffwll.ch>
Mon, 13 Feb 2012 09:57:07 +0000 (10:57 +0100)
commit99ffa1629d737295e569267cf5940758139f9ddb
tree17066a30afd3aeb27ea917f5dcb0ce74f538c087
parent53d227f282eb9fa4c7cdbfd691fa372b7ca8c4c3
drm/i915: enable forcewake voodoo also for gen6

We still have reports of missed irqs even on Sandybridge with the
HWSTAM workaround in place. Testing by the bug reporter gets rid of
them with the forcewake voodoo and no HWSTAM writes.

Because I've slightly botched the rebasing I've left out the ACTHD
readback which is also required to get IVB working. Seems to still
work on the tester's machine, so I think we should go with the more
minmal approach on SNB. Especially since I've only found weak evidence
for holding forcewake while waiting for an interrupt to arrive, but
none for the ACTHD readback.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=45181
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=45332
Tested-by: Nicolas Kalkhof nkalkhof()at()web.de
Acked-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-Off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
drivers/gpu/drm/i915/i915_irq.c
drivers/gpu/drm/i915/intel_ringbuffer.c