[Intel-gfx] [PATCH] drm/i915/ehl: Check PHY type before reading DPLL frequency

[Imre Deak]

On Tue, Mar 03, 2020 at 10:34:47AM -0800, Matt Roper wrote:
> On Tue, Mar 03, 2020 at 10:29:04AM -0800, Matt Roper wrote:
> > intel_ddi_clock_get() tests the DPLL ID against DPLL_ID_ICL_TBTPLL (2)
> > to determine whether to try to descend into a TBT-specific handler.
> > However this test will also be true when DPLL4 on EHL is used since that
> > shares the same DPLL ID (2).
> > 
> > Add an extra check to ensure the PHY is actually a Type-C PHY before
> > descending into the TBT handling.  This should ensure EHL still takes
> > the correct code path and somewhat future-proof the code as well.
> > 
> > Cc: José Roberto de Souza <jose.souza at intel.com>
> > Closes: https://gitlab.freedesktop.org/drm/intel/issues/1369
> 
> Fixes: 45e4728b87ad ("drm/i915: Move DPLL frequency calculation to intel_dpll_mgr.c")

Reviewed-by: Imre Deak <imre.deak at intel.com>

> Cc: Imre Deak <imre.deak at intel.com>
> 
> I think.
> 
> 
> Matt
> 
> > Signed-off-by: Matt Roper <matthew.d.roper at intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_ddi.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/display/intel_ddi.c b/drivers/gpu/drm/i915/display/intel_ddi.c
> > index 284219da7df8..aa3cc42b0eb9 100644
> > --- a/drivers/gpu/drm/i915/display/intel_ddi.c
> > +++ b/drivers/gpu/drm/i915/display/intel_ddi.c
> > @@ -1376,8 +1376,9 @@ static void intel_ddi_clock_get(struct intel_encoder *encoder,
> >  				struct intel_crtc_state *pipe_config)
> >  {
> >  	struct drm_i915_private *dev_priv = to_i915(encoder->base.dev);
> > +	enum phy phy = intel_port_to_phy(dev_priv, encoder->port);
> >  
> > -	if (INTEL_GEN(dev_priv) >= 11 &&
> > +	if (INTEL_GEN(dev_priv) >= 11 && intel_phy_is_tc(dev_priv, phy) &&
> >  	    intel_get_shared_dpll_id(dev_priv, pipe_config->shared_dpll) ==
> >  	    DPLL_ID_ICL_TBTPLL)
> >  		pipe_config->port_clock = icl_calc_tbt_pll_link(dev_priv,
> > -- 
> > 2.24.1
> > 
> 
> -- 
> Matt Roper
> Graphics Software Engineer
> VTT-OSGC Platform Enablement
> Intel Corporation
> (916) 356-2795