Re: [PATCH 3/4] drm/i915: Use pw_idx to derive PHY for ICL_LANE_ENABLE_AUX override

2024-03-07 Thread Ville Syrjälä
On Tue, Mar 05, 2024 at 05:14:54PM +0200, Imre Deak wrote:
> On Thu, Feb 29, 2024 at 10:03:56PM +0200, Ville Syrjala wrote:
> > From: Ville Syrjälä 
> > 
> > We don't actually know whether we should be picking the PHY
> > simply based on the AUX_CH/power well, or based on the VBT
> > defined AUX_CH->DDI->PHY relationship. At the moment we are
> > doing the former for the ANAOVRD workaround, and the latter
> > for the ICL_LANE_ENABLE_AUX override. Windows seems to use the
> > first approach for everything. So let's unify this to follow
> > that same approach for both.
> > 
> > Eventually we should try to figure out  which is actually
> > correct, or whether any of this even matters (ie. whether there
> > are any real machines where the DDI and its AUX_CH do not match
> > 1:1).
> > 
> > Note that this also changes the behaviour if we do end up
> > poking an AUX power well not associated with any port (as
> > per VBT). Previously we would have skipped the PHY register
> > write, but now we always write it.
> > 
> > Signed-off-by: Ville Syrjälä 
> > ---
> >  .../i915/display/intel_display_power_well.c   | 21 +++
> >  1 file changed, 12 insertions(+), 9 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/display/intel_display_power_well.c 
> > b/drivers/gpu/drm/i915/display/intel_display_power_well.c
> > index a1edac6ce31f..f25ad7d2c784 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display_power_well.c
> > +++ b/drivers/gpu/drm/i915/display/intel_display_power_well.c
> > @@ -419,10 +419,12 @@ icl_combo_phy_aux_power_well_enable(struct 
> > drm_i915_private *dev_priv,
> >  
> > intel_de_rmw(dev_priv, regs->driver, 0, HSW_PWR_WELL_CTL_REQ(pw_idx));
> >  
> > -   /* FIXME this is a mess */
> > -   if (phy != PHY_NONE)
> > -   intel_de_rmw(dev_priv, ICL_PORT_CL_DW12(phy),
> > -0, ICL_LANE_ENABLE_AUX);
> > +   /*
> > +* FIXME not sure if we should derive the PHY from the pw_idx, or
> > +* from the VBT defined AUX_CH->DDI->PHY mapping.
> > +*/
> > +   intel_de_rmw(dev_priv, ICL_PORT_CL_DW12(ICL_AUX_PW_TO_PHY(pw_idx)),
> > +0, ICL_LANE_ENABLE_AUX);
> 
> I wonder if the same PW -> PHY mapping could be used in
> icl_aux_power_well_enable/disable() as well (to make it more consistent
> if there is no encoder using the PW). Cross connecting combo, TC PHY AUX
> channels doesn't work anyway I think (maybe this could be actually
> checked in intel_bios_dp_aux_ch()).

We can't tell the PHY type from the pw, unless we add that
information to the power well definitions.

> 
> On the patchset:
> Reviewed-by: Imre Deak 
> 
> 
> >  
> > hsw_wait_for_power_well_enable(dev_priv, power_well, false);
> >  
> > @@ -439,14 +441,15 @@ icl_combo_phy_aux_power_well_disable(struct 
> > drm_i915_private *dev_priv,
> >  {
> > const struct i915_power_well_regs *regs = power_well->desc->ops->regs;
> > int pw_idx = i915_power_well_instance(power_well)->hsw.idx;
> > -   enum phy phy = icl_aux_pw_to_phy(dev_priv, power_well);
> >  
> > drm_WARN_ON(_priv->drm, !IS_ICELAKE(dev_priv));
> >  
> > -   /* FIXME this is a mess */
> > -   if (phy != PHY_NONE)
> > -   intel_de_rmw(dev_priv, ICL_PORT_CL_DW12(phy),
> > -ICL_LANE_ENABLE_AUX, 0);
> > +   /*
> > +* FIXME not sure if we should derive the PHY from the pw_idx, or
> > +* from the VBT defined AUX_CH->DDI->PHY mapping.
> > +*/
> > +   intel_de_rmw(dev_priv, ICL_PORT_CL_DW12(ICL_AUX_PW_TO_PHY(pw_idx)),
> > +ICL_LANE_ENABLE_AUX, 0);
> >  
> > intel_de_rmw(dev_priv, regs->driver, HSW_PWR_WELL_CTL_REQ(pw_idx), 0);
> >  
> > -- 
> > 2.43.0
> > 

-- 
Ville Syrjälä
Intel


Re: [PATCH 3/4] drm/i915: Use pw_idx to derive PHY for ICL_LANE_ENABLE_AUX override

2024-03-05 Thread Imre Deak
On Thu, Feb 29, 2024 at 10:03:56PM +0200, Ville Syrjala wrote:
> From: Ville Syrjälä 
> 
> We don't actually know whether we should be picking the PHY
> simply based on the AUX_CH/power well, or based on the VBT
> defined AUX_CH->DDI->PHY relationship. At the moment we are
> doing the former for the ANAOVRD workaround, and the latter
> for the ICL_LANE_ENABLE_AUX override. Windows seems to use the
> first approach for everything. So let's unify this to follow
> that same approach for both.
> 
> Eventually we should try to figure out  which is actually
> correct, or whether any of this even matters (ie. whether there
> are any real machines where the DDI and its AUX_CH do not match
> 1:1).
> 
> Note that this also changes the behaviour if we do end up
> poking an AUX power well not associated with any port (as
> per VBT). Previously we would have skipped the PHY register
> write, but now we always write it.
> 
> Signed-off-by: Ville Syrjälä 
> ---
>  .../i915/display/intel_display_power_well.c   | 21 +++
>  1 file changed, 12 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_display_power_well.c 
> b/drivers/gpu/drm/i915/display/intel_display_power_well.c
> index a1edac6ce31f..f25ad7d2c784 100644
> --- a/drivers/gpu/drm/i915/display/intel_display_power_well.c
> +++ b/drivers/gpu/drm/i915/display/intel_display_power_well.c
> @@ -419,10 +419,12 @@ icl_combo_phy_aux_power_well_enable(struct 
> drm_i915_private *dev_priv,
>  
>   intel_de_rmw(dev_priv, regs->driver, 0, HSW_PWR_WELL_CTL_REQ(pw_idx));
>  
> - /* FIXME this is a mess */
> - if (phy != PHY_NONE)
> - intel_de_rmw(dev_priv, ICL_PORT_CL_DW12(phy),
> -  0, ICL_LANE_ENABLE_AUX);
> + /*
> +  * FIXME not sure if we should derive the PHY from the pw_idx, or
> +  * from the VBT defined AUX_CH->DDI->PHY mapping.
> +  */
> + intel_de_rmw(dev_priv, ICL_PORT_CL_DW12(ICL_AUX_PW_TO_PHY(pw_idx)),
> +  0, ICL_LANE_ENABLE_AUX);

I wonder if the same PW -> PHY mapping could be used in
icl_aux_power_well_enable/disable() as well (to make it more consistent
if there is no encoder using the PW). Cross connecting combo, TC PHY AUX
channels doesn't work anyway I think (maybe this could be actually
checked in intel_bios_dp_aux_ch()).

On the patchset:
Reviewed-by: Imre Deak 


>  
>   hsw_wait_for_power_well_enable(dev_priv, power_well, false);
>  
> @@ -439,14 +441,15 @@ icl_combo_phy_aux_power_well_disable(struct 
> drm_i915_private *dev_priv,
>  {
>   const struct i915_power_well_regs *regs = power_well->desc->ops->regs;
>   int pw_idx = i915_power_well_instance(power_well)->hsw.idx;
> - enum phy phy = icl_aux_pw_to_phy(dev_priv, power_well);
>  
>   drm_WARN_ON(_priv->drm, !IS_ICELAKE(dev_priv));
>  
> - /* FIXME this is a mess */
> - if (phy != PHY_NONE)
> - intel_de_rmw(dev_priv, ICL_PORT_CL_DW12(phy),
> -  ICL_LANE_ENABLE_AUX, 0);
> + /*
> +  * FIXME not sure if we should derive the PHY from the pw_idx, or
> +  * from the VBT defined AUX_CH->DDI->PHY mapping.
> +  */
> + intel_de_rmw(dev_priv, ICL_PORT_CL_DW12(ICL_AUX_PW_TO_PHY(pw_idx)),
> +  ICL_LANE_ENABLE_AUX, 0);
>  
>   intel_de_rmw(dev_priv, regs->driver, HSW_PWR_WELL_CTL_REQ(pw_idx), 0);
>  
> -- 
> 2.43.0
>