[Intel-gfx] [PATCH] drm/i915: preserve pipe A quirk in i9xx_set_pipeconf

[Daniel Vetter]

On Tue, Sep 24, 2013 at 01:05:07PM +0100, Chris Wilson wrote:
> On Tue, Sep 24, 2013 at 11:46:14AM +0200, Daniel Vetter wrote:
> > This regression has been introduced in
> > 
> > commit 9f11a9e4e50006b615ba94722dfc33ced89664cf
> > Author: Daniel Vetter <daniel.vetter at ffwll.ch>
> > Date:   Thu Jun 13 00:54:58 2013 +0200
> > 
> >     drm/i915: set up PIPECONF explicitly for i9xx/vlv platforms
> > 
> > Ville brough up the idea that this is just the pipe A quirk gone
> > wrong.
> > 
> > Note that after resume the bios might or might not have enabled pipe A
> > already.  We have a bit of magic to make sure that on resume we set up
> > a decent mode for pipe A, but I fear if I just smash pipe A to always
> > on we'd enable it in a bogus state and hang the hw. Hence the
> > readback.
> > 
> > v2: Clarify the logic a bit as suggested by Chris. Also amend the
> > commit message to clarify why we don't unconditionally enable the
> > pipe.
> > 
> > Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=66462
> > References: https://lkml.org/lkml/2013/8/26/238
> > Cc: Meelis Roos <mroos at ut.ee>
> > Cc: Chris Wilson <chris at chris-wilson.co.uk>
> > Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
> 
> Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>
> 
> would still prefer pipeconf |= PIPECONF_ENABLE though.

Yeah, makes sense. Fixed and applied, thanks for the review.
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch