Re: [PATCH v2] drm/i915/fbc: update the impacted platforms in wa_22014263786

["Govindapillai, Vinod" <vinod.govindapillai@intel.com>]

On Wed, 2025-10-01 at 13:03 +0300, Jani Nikula wrote:
> On Wed, 01 Oct 2025, Vinod Govindapillai <vinod.govindapillai@intel.com> wrote:
> > wa_22014263786 is not applicable to the BMG and hence exclude it
> > from the wa.
> > 
> > v2: Limit this wa to display verion 11 to 14, drop DG2 from the
> >     exclusion list, use intel_display_wa (Lucas)
> > 
> > Bspec: 74212, 66624
> > Signed-off-by: Vinod Govindapillai <vinod.govindapillai@intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_display_wa.c | 12 ++++++++++++
> >  drivers/gpu/drm/i915/display/intel_display_wa.h |  1 +
> >  drivers/gpu/drm/i915/display/intel_fbc.c        |  3 +--
> >  3 files changed, 14 insertions(+), 2 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/display/intel_display_wa.c
> > b/drivers/gpu/drm/i915/display/intel_display_wa.c
> > index 31cd2c9cd488..7ca238725e30 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display_wa.c
> > +++ b/drivers/gpu/drm/i915/display/intel_display_wa.c
> > @@ -52,6 +52,16 @@ static bool intel_display_needs_wa_16025573575(struct intel_display *display)
> >  	return DISPLAY_VERx100(display) == 3000 || DISPLAY_VERx100(display) == 3002;
> >  }
> >  
> > +/*
> > + * Wa_22014263786:
> > + * Fixes: Screen flicker with FBC and Package C state enabled
> > + * Workaround: Forced SLB invalidation before start of new frame.
> > + */
> > +static bool intel_display_needs_wa_22014263786(struct intel_display *display)
> > +{
> > +	return DISPLAY_VERx100(display) >= 1100 && DISPLAY_VERx100(display) < 1401;
> 
> IS_DISPLAY_VERx100(display, 1100, 1400)
> 
> Also I'm not sure if we really need separate functions for one-liners
> like this. The documentation could be in the switch case too? *shrug*.

Thanks. I will update that. I will get rid of the comments. I dont think it adds any extra
information other than what it can be found from wa details.

BR
Vinod
> 
> BR,
> Jani.
> 
> > +}
> > +
> >  /*
> >   * Wa_14011503117:
> >   * Fixes: Before enabling the scaler DE fatal error is masked
> > @@ -67,6 +77,8 @@ bool __intel_display_wa(struct intel_display *display, enum intel_display_wa
> > wa,
> >  		return intel_display_needs_wa_16025573575(display);
> >  	case INTEL_DISPLAY_WA_14011503117:
> >  		return DISPLAY_VER(display) == 13;
> > +	case INTEL_DISPLAY_WA_22014263786:
> > +		return intel_display_needs_wa_22014263786(display);
> >  	default:
> >  		drm_WARN(display->drm, 1, "Missing Wa number: %s\n", name);
> >  		break;
> > diff --git a/drivers/gpu/drm/i915/display/intel_display_wa.h
> > b/drivers/gpu/drm/i915/display/intel_display_wa.h
> > index abc1df83f066..3644e8e2b724 100644
> > --- a/drivers/gpu/drm/i915/display/intel_display_wa.h
> > +++ b/drivers/gpu/drm/i915/display/intel_display_wa.h
> > @@ -25,6 +25,7 @@ enum intel_display_wa {
> >  	INTEL_DISPLAY_WA_16023588340,
> >  	INTEL_DISPLAY_WA_16025573575,
> >  	INTEL_DISPLAY_WA_14011503117,
> > +	INTEL_DISPLAY_WA_22014263786,
> >  };
> >  
> >  bool __intel_display_wa(struct intel_display *display, enum intel_display_wa wa, const char
> > *name);
> > diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c b/drivers/gpu/drm/i915/display/intel_fbc.c
> > index 0d380c825791..9607fdcb0cc0 100644
> > --- a/drivers/gpu/drm/i915/display/intel_fbc.c
> > +++ b/drivers/gpu/drm/i915/display/intel_fbc.c
> > @@ -933,8 +933,7 @@ static void intel_fbc_program_workarounds(struct intel_fbc *fbc)
> >  		intel_de_rmw(display, ILK_DPFC_CHICKEN(fbc->id),
> >  			     0, DPFC_CHICKEN_COMP_DUMMY_PIXEL);
> >  
> > -	/* Wa_22014263786:icl,jsl,tgl,dg1,rkl,adls,adlp,mtl */
> > -	if (DISPLAY_VER(display) >= 11 && !display->platform.dg2)
> > +	if (intel_display_wa(display, 22014263786))
> >  		intel_de_rmw(display, ILK_DPFC_CHICKEN(fbc->id),
> >  			     0, DPFC_CHICKEN_FORCE_SLB_INVALIDATION);
>