Re: [PATCH 09/10] drm/i915: Use intel_ddi_get_config() for MST

Ville Syrjälä
2017-10-27T11:55:34Z

On Fri, Oct 27, 2017 at 01:43:03PM +0200, Maarten Lankhorst wrote:
> Op 19-10-17 om 15:37 schreef Ville Syrjala:
> > From: Ville Syrjälä <ville.syrjala@linux.intel.com>
> >
> > Eliminate the partially duplicated DDI readout code from MST, and
> > instead just call intel_ddi_get_config(). As a nice bonus we get
> > more cross checking as intel_ddi_get_config() will populate
> > output_types based on the actual mode of the DDI port.
> >
> > Additonally intel_ddi_get_config() must be changed to get the crtc
> > from the passed in crtc state rather than from the encoder->crtc link.
> > encoder->crtc really shouldn't be used anyway.
> >
> > Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> I looked and noticed 2 small differences, one is the GEN9_LP part, the other is
> min_voltage_level. Is this also a bugfix because of this?

The min_voltage thing should be fine. We should have it in both DDI and
MST code (unless I made a mistake when adding it, but doesn't look like
I did).

The bxt lat_optim thing is a real issue. Looks like I need to add that to
the MST compute_config. Though as a whole it feels a bit overkill to
track that particular piece of state specifically. We don't do that on
CHV either, which has the exact same PHY.

--
Ville Syrjälä
Intel OTC