RE: [PATCH v4] drm/i915/gen9bc: Handle TGP PCH during suspend/resume

From: Surendrakumar Upadhyay, TejaskumarX
Date: Wed Feb 17 2021 - 23:37:36 EST




> -----Original Message-----
> From: Lyude Paul <lyude@xxxxxxxxxx>
> Sent: 18 February 2021 02:49
> To: Deak, Imre <imre.deak@xxxxxxxxx>
> Cc: intel-gfx@xxxxxxxxxxxxxxxxxxxxx; Surendrakumar Upadhyay, TejaskumarX
> <tejaskumarx.surendrakumar.upadhyay@xxxxxxxxx>; Roper, Matthew D
> <matthew.d.roper@xxxxxxxxx>; Jani Nikula <jani.nikula@xxxxxxxxxxxxxxx>;
> Joonas Lahtinen <joonas.lahtinen@xxxxxxxxxxxxxxx>; Vivi, Rodrigo
> <rodrigo.vivi@xxxxxxxxx>; David Airlie <airlied@xxxxxxxx>; Daniel Vetter
> <daniel@xxxxxxxx>; open list:DRM DRIVERS <dri-
> devel@xxxxxxxxxxxxxxxxxxxxx>; open list <linux-kernel@xxxxxxxxxxxxxxx>
> Subject: Re: [PATCH v4] drm/i915/gen9bc: Handle TGP PCH during
> suspend/resume
>
> On Wed, 2021-02-17 at 23:18 +0200, Imre Deak wrote:
> > On Wed, Feb 17, 2021 at 01:00:16PM -0500, Lyude Paul wrote:
> > > From: Tejas Upadhyay
> <tejaskumarx.surendrakumar.upadhyay@xxxxxxxxx>
> > >
> > > For Legacy S3 suspend/resume GEN9 BC needs to enable and setup TGP
> > > PCH.
> > >
> > > v2:
> > > * Move Wa_14010685332 into it's own function - vsyrjala
> > > * Add TODO comment about figuring out if we can move this workaround
> > > - imre
> > > v3:
> > > * Rename cnp_irq_post_reset() to cnp_display_clock_wa()
> > > * Add TODO item mentioning we need to clarify which platforms this
> > >   workaround applies to
> > > * Just use ibx_irq_reset() in gen8_irq_reset(). This code should be
> > >   functionally equivalent on gen9 bc to the code v2 added
> > > * Drop icp_hpd_irq_setup() call in spt_hpd_irq_setup(), this looks
> > > to be
> > >   more or less identical to spt_hpd_irq_setup() minus additionally
> > > enabling
> > >   one port. Will update i915 to use icp_hpd_irq_setup() for ICP in a
> > >   separate patch.
> > > v4:
> > > * Revert Wa_14010685332 system list in comments to how it was before
> > > * Add back HAS_PCH_SPLIT() check before calling ibx_irq_reset()
> > >
> > > Cc: Matt Roper <matthew.d.roper@xxxxxxxxx>
> > > Signed-off-by: Tejas Upadhyay
> > > <tejaskumarx.surendrakumar.upadhyay@xxxxxxxxx>
> > > Signed-off-by: Lyude Paul <lyude@xxxxxxxxxx>
> >
> > Thanks, looks ok to me:
> > Reviewed-by: Imre Deak <imre.deak@xxxxxxxxx>
> >
> > nit: cnp_display_clock_gating_wa() would be an even better name, could
> > be renamed while applying.
>
> Sure thing. JFYI - I'm going to hold off on pushing this patch until I've got
> confirmation from the OEMs this is for that these patches still fix their issues
> (since I unfortunately don't have any access to this hardware).

I can follow up with OEM to test or I can get it tested in my LAB, as I have RKL RVP (CML CPU) + TGP PCH with me.

>
> >
> > > ---
> > >  drivers/gpu/drm/i915/i915_irq.c | 49
> > > +++++++++++++++++++++------------
> > >  1 file changed, 32 insertions(+), 17 deletions(-)
> > >
> > > diff --git a/drivers/gpu/drm/i915/i915_irq.c
> > > b/drivers/gpu/drm/i915/i915_irq.c index 98145a7f28a4..9b56a8f81e1a
> > > 100644
> > > --- a/drivers/gpu/drm/i915/i915_irq.c
> > > +++ b/drivers/gpu/drm/i915/i915_irq.c
> > > @@ -3040,6 +3040,24 @@ static void valleyview_irq_reset(struct
> > > drm_i915_private *dev_priv)
> > >         spin_unlock_irq(&dev_priv->irq_lock);
> > >  }
> > >
> > > +static void cnp_display_clock_wa(struct drm_i915_private *dev_priv)
> > > +{
> > > +       struct intel_uncore *uncore = &dev_priv->uncore;
> > > +
> > > +       /*
> > > +        * Wa_14010685332:cnp/cmp,tgp,adp
> > > +        * TODO: Clarify which platforms this applies to
> > > +        * TODO: Figure out if this workaround can be applied in the
> > > +s0ix
> > > suspend/resume handlers as
> > > +        * on earlier platforms and whether the workaround is also
> > > +needed
> > > for runtime suspend/resume
> > > +        */
> > > +       if (INTEL_PCH_TYPE(dev_priv) == PCH_CNP ||
> > > +           (INTEL_PCH_TYPE(dev_priv) >= PCH_TGP &&
> > > +INTEL_PCH_TYPE(dev_priv)
> > > < PCH_DG1)) {
> > > +               intel_uncore_rmw(uncore, SOUTH_CHICKEN1,
> > > SBCLK_RUN_REFCLK_DIS,
> > > +                                SBCLK_RUN_REFCLK_DIS);
> > > +               intel_uncore_rmw(uncore, SOUTH_CHICKEN1,
> > > SBCLK_RUN_REFCLK_DIS, 0);
> > > +       }
> > > +}
> > > +
> > >  static void gen8_irq_reset(struct drm_i915_private *dev_priv)
> > >  {
> > >         struct intel_uncore *uncore = &dev_priv->uncore; @@ -3063,6
> > > +3081,8 @@ static void gen8_irq_reset(struct drm_i915_private
> > > *dev_priv)
> > >
> > >         if (HAS_PCH_SPLIT(dev_priv))
> > >                 ibx_irq_reset(dev_priv);
> > > +
> > > +       cnp_display_clock_wa(dev_priv);
> > >  }
> > >
> > >  static void gen11_display_irq_reset(struct drm_i915_private
> > > *dev_priv) @@ -3104,15 +3124,7 @@ static void
> > > gen11_display_irq_reset(struct drm_i915_private *dev_priv)
> > >         if (INTEL_PCH_TYPE(dev_priv) >= PCH_ICP)
> > >                 GEN3_IRQ_RESET(uncore, SDE);
> > >
> > > -       /* Wa_14010685332:cnp/cmp,tgp,adp */
> > > -       if (INTEL_PCH_TYPE(dev_priv) == PCH_CNP ||
> > > -           (INTEL_PCH_TYPE(dev_priv) >= PCH_TGP &&
> > > -            INTEL_PCH_TYPE(dev_priv) < PCH_DG1)) {
> > > -               intel_uncore_rmw(uncore, SOUTH_CHICKEN1,
> > > -                                SBCLK_RUN_REFCLK_DIS,
> > > SBCLK_RUN_REFCLK_DIS);
> > > -               intel_uncore_rmw(uncore, SOUTH_CHICKEN1,
> > > -                                SBCLK_RUN_REFCLK_DIS, 0);
> > > -       }
> > > +       cnp_display_clock_wa(dev_priv);
> > >  }
> > >
> > >  static void gen11_irq_reset(struct drm_i915_private *dev_priv) @@
> > > -3764,9 +3776,19 @@ static void gen8_de_irq_postinstall(struct
> > > drm_i915_private *dev_priv)
> > >         }
> > >  }
> > >
> > > +static void icp_irq_postinstall(struct drm_i915_private *dev_priv)
> > > +{
> > > +       struct intel_uncore *uncore = &dev_priv->uncore;
> > > +       u32 mask = SDE_GMBUS_ICP;
> > > +
> > > +       GEN3_IRQ_INIT(uncore, SDE, ~mask, 0xffffffff); }
> > > +
> > >  static void gen8_irq_postinstall(struct drm_i915_private *dev_priv)
> > >  {
> > > -       if (HAS_PCH_SPLIT(dev_priv))
> > > +       if (INTEL_PCH_TYPE(dev_priv) >= PCH_ICP)
> > > +               icp_irq_postinstall(dev_priv);
> > > +       else if (HAS_PCH_SPLIT(dev_priv))
> > >                 ibx_irq_postinstall(dev_priv);
> > >
> > >         gen8_gt_irq_postinstall(&dev_priv->gt);
> > > @@ -3775,13 +3797,6 @@ static void gen8_irq_postinstall(struct
> > > drm_i915_private *dev_priv)
> > >         gen8_master_intr_enable(dev_priv->uncore.regs);
> > >  }
> > >
> > > -static void icp_irq_postinstall(struct drm_i915_private *dev_priv)
> > > -{
> > > -       struct intel_uncore *uncore = &dev_priv->uncore;
> > > -       u32 mask = SDE_GMBUS_ICP;
> > > -
> > > -       GEN3_IRQ_INIT(uncore, SDE, ~mask, 0xffffffff); -}
> > >
> > >  static void gen11_irq_postinstall(struct drm_i915_private
> > > *dev_priv)
> > >  {
> > > --
> > > 2.29.2
> > >
> >
>
> --
> Sincerely,
> Lyude Paul (she/her)
> Software Engineer at Red Hat
>
> Note: I deal with a lot of emails and have a lot of bugs on my plate. If you've
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