[Intel-gfx] [PATCH] drm/i915/bxt: fix DDI PHY vswing scale value setting

[Damien Lespiau]

On Wed, Jun 10, 2015 at 09:18:29AM -0700, Matt Roper wrote:
> On Thu, Jun 04, 2015 at 06:01:35PM +0300, Imre Deak wrote:
> > According to bspec the DDI PHY vswing scale value is "don't care" in
> > case the scale enable bit [27] is clear. But this doesn't seem to be
> > correct. The scale value seems to also matter if the scale mode bit
> > [26] is set. So both bit 26 and 27 depend on the value. Setting the
> > scale value to 0 while either bit is set results in a failed modeset on
> > HDMI (sink reports no signal).
> > 
> > After reset the scale value is 0x98, but according to the spec we have
> > to program it to 0x9a. So for consistency program it always to 0x9a
> > regardless of the scale enable bit.
> > 
> > Signed-off-by: Imre Deak <imre.deak at intel.com>
> 
> This patch successfully enables HDMI display for my team.
> 
> Tested-by: Matt Roper <matthew.d.roper at intel.com>

I believe this should be enough of a good reason for merging at this
stage.

Acked-by: Damien Lespiau <damien.lespiau at intel.com>

-- 
Damien