Re: [PATCH 7/3] drm/i915: remove wait_for_vblank argument form intel_enable_pipe

["Ville Syrjälä" <ville.syrjala@linux.intel.com>]

On Mon, Feb 10, 2014 at 02:33:07PM +0000, Damien Lespiau wrote:
> On Fri, Jan 17, 2014 at 01:51:12PM -0200, Paulo Zanoni wrote:
> > From: Paulo Zanoni <paulo.r.zanoni@intel.com>
> > 
> > Add a nice comment explaining why we shouldn't wait for a vblank on
> > all cases, wait based on the HW gen, and add a comment saying we
> > should probably skip that wait on some of the previous HW gens.
> > 
> > Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
> 
> 
> Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
> 
> Looking at BSpec for info on this, I didn't find any mention of having
> to wait of a vblank indeed. There's a nice workaround we don't seem to
> implement though (underrun when switching from one to multi-pipes,
> display buffer related). I'm sure that's somewhere in a TODO list :)

We implement something for HSW, but I'm not sure it's quite enough.
In any case I have patches lined up for disabling LP1+ watermarks when
doing one<->many pipes switch for PCH platforms. Which reminds I need
to stop slacking off and get those posted soon.

-- 
Ville Syrjälä
Intel OTC