[Intel-gfx] [PATCH 1/2] drm/i915: clean up media reset on gm45

[Chris Wilson]

On Tue, Jul 09, 2013 at 02:44:26PM +0200, Daniel Vetter wrote:
> Originally I've thought that this fixes up the reset issues on my
> gm45, but that was just a red herring due to b0rked testing.
> 
> Still I much prefer writing the right values (all other fields are
> reserved) instead of potentially dragging gunk around. Hence also
> clear the register to 0 after a reset.
> 
> Note that Cspec is a bit confused and doesn't explicitly say that all
> the other bits in this register are "reserved, mbz" like usually.
> Instead they're marked as "r/o, default value = 0" which semantically
> amounts to the same thing.
> 
> v2: Stop claiming this fixes anything and return 0 if successful
> instead of stack garbage.
> 
> v3: Pimp the commit message to explain exactly why I think the docs
> allow us to ditch the rmw cycle, spurred by a discussion with Chris.
> 
> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
Bugzilla?
Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>
-Chris

-- 
Chris Wilson, Intel Open Source Technology Centre