[Intel-gfx] [PATCH] drm/i915/d13: Fix unclaimed accesses while loading PIPEDMC-C/D

[Murthy, Arun R]

Reviewed-by: Arun R Murthy <arun.r.murthy at intel.com>

> -----Original Message-----
> From: Deak, Imre <imre.deak at intel.com>
> Sent: Wednesday, August 10, 2022 6:05 PM
> To: Murthy, Arun R <arun.r.murthy at intel.com>
> Cc: intel-gfx at lists.freedesktop.org
> Subject: Re: [Intel-gfx] [PATCH] drm/i915/d13: Fix unclaimed accesses while
> loading PIPEDMC-C/D
> 
> On Wed, Aug 10, 2022 at 06:48:24AM +0300, Murthy, Arun R wrote:
> > [...]
> > > diff --git a/drivers/gpu/drm/i915/display/intel_dmc.c
> > > b/drivers/gpu/drm/i915/display/intel_dmc.c
> > > index 00e18a4a5a5a4..6c35212c36256 100644
> > > --- a/drivers/gpu/drm/i915/display/intel_dmc.c
> > > +++ b/drivers/gpu/drm/i915/display/intel_dmc.c
> > > @@ -383,6 +383,30 @@ static void disable_all_event_handlers(struct
> > > drm_i915_private *i915)
> > >       }
> > >  }
> > >
> > > +static void pipedmc_clock_gating_wa(struct drm_i915_private *i915,
> > > +bool
> > > +enable) {
> > > +     enum pipe pipe;
> > > +
> > > +     if (DISPLAY_VER(i915) != 13)
> > > +             return;
> > > +
> > This function will be called from bxt_display_core_init() as well.
> 
> Yes, this function is called whenever the DMC firmware needs to be loaded
> and initialized/uninitialized.
> 
> > Do we need this WA for bxt as well?
> 
> The above display version check makes sure that the WA is only applied on
> relevant platforms. For BXT DISPLAY_VER()==9 (for GLK it's 10), for DG2/ADLP
> DISPLAY_VER()=13.

Was thinking if its required for bxt as well. This confirms! Thanks.

Thanks and Regards,
Arun R Murthy
--------------------