Re: [PATCH 3/4] drm/i915: ILK also needs that last fix

From: Ben Widawsky <ben@bwidawsk.net>
To: Daniel Vetter <daniel@ffwll.ch>
Cc: intel-gfx@lists.freedesktop.org
Subject: Re: [PATCH 3/4] drm/i915: ILK also needs that last fix
Date: Mon, 15 Oct 2012 20:21:41 -0700	[thread overview]
Message-ID: <20121015202141.00007429@unknown> (raw)
In-Reply-To: <20121015185922.GA5753@phenom.ffwll.local>

On Mon, 15 Oct 2012 20:59:22 +0200
Daniel Vetter <daniel@ffwll.ch> wrote:

> On Wed, Oct 03, 2012 at 07:34:23PM -0700, Ben Widawsky wrote:
> > That fix was the disable render deptch cache pipeline flush
> > 
> > Signed-off-by: Ben Widawsky <ben@bwidawsk.net>
> 
> I've stumbled over the same one, but my docs here suggest i965g/gm45
> need it, too:
> 
> http://cgit.freedesktop.org/~danvet/drm/commit/?h=ilk-wa-pile&id=37c4c82b8cdbcf5adccad97f0b45747ba37ed659
> 
> Have you checked whether we don't need this on ivb/vlv/hsw, too?

I did check whether the windows driver does it for those platforms, and
the answer is no. So the answer to your question is maybe because who
knows what exists in some other doc somewhere in the metaverse. I think
this is a good enough start though since it seems SNB was definitely a
bit buggier than IVB.

> 
> Also, for w/a patches based on the vpg w/a database, please include
> the vpg w/a name tag both in the commit message and in a code comment
> somewhere.

Good idea. If you're okay with longer commit message subjects, I'd even
suggest putting it there to make it even a bit easier to search for.

> -Daniel
> > ---
> >  drivers/gpu/drm/i915/intel_pm.c | 2 ++
> >  1 file changed, 2 insertions(+)
> > 
> > diff --git a/drivers/gpu/drm/i915/intel_pm.c
> > b/drivers/gpu/drm/i915/intel_pm.c index f1800ca..8aafa45 100644
> > --- a/drivers/gpu/drm/i915/intel_pm.c
> > +++ b/drivers/gpu/drm/i915/intel_pm.c
> > @@ -3338,6 +3338,8 @@ static void ironlake_init_clock_gating(struct
> > drm_device *dev) I915_WRITE(WM2_LP_ILK, 0);
> >  	I915_WRITE(WM1_LP_ILK, 0);
> >  
> > +	I915_WRITE(CACHE_MODE_0,
> > +
> > _MASKED_BIT_ENABLE(CM0_RC_PIPELINE_FLUSH_DISABLE)); /*
> >  	 * Based on the document from hardware guys the following
> > bits
> >  	 * should be set unconditionally in order to enable FBC.
> > -- 
> > 1.7.12.2
> > 
> > _______________________________________________
> > Intel-gfx mailing list
> > Intel-gfx@lists.freedesktop.org
> > http://lists.freedesktop.org/mailman/listinfo/intel-gfx
> 