[Intel-gfx] [PATCH 3/5] drm/i915: Power up combo PHY lanes for for HDMI as well

[Imre Deak]

On Fri, Jan 29, 2021 at 07:18:03PM +0200, Ville Syrjälä wrote:
> On Fri, Jan 29, 2021 at 07:06:33PM +0200, Imre Deak wrote:
> > On Thu, Jan 28, 2021 at 05:59:46PM +0200, Ville Syrjala wrote:
> > > From: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > > 
> > > Currently we only explicitly power up the combo PHY lanes
> > > for DP. The spec says we should do it for HDMI as well.
> > > 
> > > Cc: stable at vger.kernel.org
> > > Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> > > ---
> > >  drivers/gpu/drm/i915/display/intel_ddi.c | 2 ++
> > >  1 file changed, 2 insertions(+)
> > > 
> > > diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
> > > index 88cc6e2fbe91..8fbeb8c24efb 100644
> > > --- a/drivers/gpu/drm/i915/display/intel_ddi.c
> > > +++ b/drivers/gpu/drm/i915/display/intel_ddi.c
> > > @@ -4337,6 +4337,8 @@ static void intel_enable_ddi_hdmi(struct intel_atomic_state *state,
> > >  		intel_de_write(dev_priv, reg, val);
> > >  	}
> > >  
> > > +	intel_ddi_power_up_lanes(encoder, crtc_state);
> > > +
> > 
> > Not sure if it matters, but the spec says to apply WA #1143 just before
> > enabling DDI_BUF_CTL.
> 
> intel_ddi_power_up_lanes() is a nop for pre-icl, so we still do that.

Ok, missed this detail, it looks ok then:
Reviewed-by: Imre Deak <imre.deak at intel.com>

> Also not sure what the final fate of that w/a will be since apparently
> it's not working as intended.
> 
> That said I was debating with myself what order to put these in, but
> in the end I chose this order because the w/a is related to the
> vswing programming, and so wanted to keep it next to the BUF_TRANS
> programming.
>
> > >  	/* In HDMI/DVI mode, the port width, and swing/emphasis values
> > >  	 * are ignored so nothing special needs to be done besides
> > >  	 * enabling the port.
> > > -- 
> > > 2.26.2
> > > 
> > > _______________________________________________
> > > Intel-gfx mailing list
> > > Intel-gfx at lists.freedesktop.org
> > > https://lists.freedesktop.org/mailman/listinfo/intel-gfx
> 
> -- 
> Ville Syrjälä
> Intel