On Tue, Dec 16, 2025 at 04:05:08PM +0200, Vinod Govindapillai wrote: > For DG2, wa_22014263786 is applicable only if the number of active > planes is greater than 1 in pipe A and pipe B. Cursor planes and > any planes on pipe C or pipe D are not considered for this. > > Bspec: 54077, 72197 > Signed-off-by: Vinod Govindapillai <[email protected]> > --- > .../gpu/drm/i915/display/intel_display_wa.c | 29 ++++++++++++++++++- > drivers/gpu/drm/i915/display/intel_fbc.c | 6 ++++ > 2 files changed, 34 insertions(+), 1 deletion(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_display_wa.c > b/drivers/gpu/drm/i915/display/intel_display_wa.c > index a00af39f7538..ffc2356283aa 100644 > --- a/drivers/gpu/drm/i915/display/intel_display_wa.c > +++ b/drivers/gpu/drm/i915/display/intel_display_wa.c > @@ -7,6 +7,7 @@ > > #include "i915_reg.h" > #include "intel_de.h" > +#include "intel_display_types.h" > #include "intel_display_core.h" > #include "intel_display_regs.h" > #include "intel_display_wa.h" > @@ -53,6 +54,32 @@ static bool intel_display_needs_wa_16025573575(struct > intel_display *display) > DISPLAY_VERx100(display) == 3500; > } > > +static bool intel_display_needs_wa_22014263786(struct intel_display *display) > +{ > + if (!IS_DISPLAY_VERx100(display, 1100, 1400)) > + return false; > + > + if (display->platform.dg2) { > + u8 pipe_mask = PIPE_A | PIPE_B; > + int num_active_planes = 0; > + struct intel_crtc *crtc; > + > + for_each_intel_crtc_in_pipe_mask(display->drm, crtc, pipe_mask) > { > + const struct intel_crtc_state *crtc_state = > + to_intel_crtc_state(crtc->base.state); > + u8 active_planes = > + crtc_state->active_planes & ~BIT(PLANE_CURSOR); > + > + num_active_planes += hweight8(active_planes); > + } > + > + if (num_active_planes <= 1) > + return false; > + } > + > + return true; > +} > + > /* > * Wa_14011503117: > * Fixes: Before enabling the scaler DE fatal error is masked > @@ -69,7 +96,7 @@ bool __intel_display_wa(struct intel_display *display, enum > intel_display_wa wa, > case INTEL_DISPLAY_WA_14011503117: > return DISPLAY_VER(display) == 13; > case INTEL_DISPLAY_WA_22014263786: > - return IS_DISPLAY_VERx100(display, 1100, 1400); > + return intel_display_needs_wa_22014263786(display); > case INTEL_DISPLAY_WA_15018326506: > return display->platform.battlemage; > case INTEL_DISPLAY_WA_14025769978: > diff --git a/drivers/gpu/drm/i915/display/intel_fbc.c > b/drivers/gpu/drm/i915/display/intel_fbc.c > index fef2f35ff1e9..5b0a83cb5386 100644 > --- a/drivers/gpu/drm/i915/display/intel_fbc.c > +++ b/drivers/gpu/drm/i915/display/intel_fbc.c > @@ -944,10 +944,16 @@ static void intel_fbc_program_workarounds(struct > intel_fbc *fbc) > * Wa_22014263786 > * Fixes: Screen flicker with FBC and Package C state enabled > * Workaround: Forced SLB invalidation before start of new frame. > + * For DG2, wa is applied only if the number of planes > + * in PIPE A and PIPE B is > 1. If the wa condition is > + * not met, this chicken bit must be unset for DG2.
I might be misremembering the FBC flows in the driver now, but I don't think we come back to this point and re-evaluate the workaround once FBC has been enabled as other planes get enabled/disabled by later atomic transactions do we? E.g., if we initially just have a single plane enabled on pipes A/B, we'll apply the workaround as expected. But then if we later turn on an additional plane are we going to notice that the conditions have changed and that we now need to disable the workaround? Or alternatively if we have two planes turned on initially (so workaround not applied), but then we disable the one that FBC isn't bound to are we going to notice that we need to come back and apply the workaround? Matt > */ > if (intel_display_wa(display, 22014263786)) > intel_de_rmw(display, ILK_DPFC_CHICKEN(fbc->id), > 0, DPFC_CHICKEN_FORCE_SLB_INVALIDATION); > + else if (display->platform.dg2) > + intel_de_rmw(display, ILK_DPFC_CHICKEN(fbc->id), > + DPFC_CHICKEN_FORCE_SLB_INVALIDATION, 0); > > /* wa_18038517565 Disable DPFC clock gating before FBC enable */ > if (display->platform.dg2 || DISPLAY_VER(display) >= 14) > -- > 2.43.0 > -- Matt Roper Graphics Software Engineer Linux GPU Platform Enablement Intel Corporation
