On Thu, 11 Nov 2021, Matt Roper <matthew.d.ro...@intel.com> wrote: > This workaround is documented a bit strangely in the bspec; it's listed > as an A0 workaround, but the description clarifies that the workaround > is implicitly handled by the hardware and what the driver really needs > to do is program a chicken bit to reenable some internal behavior. > > Signed-off-by: Matt Roper <matthew.d.ro...@intel.com> > --- > drivers/gpu/drm/i915/display/intel_display.c | 4 ++++ > drivers/gpu/drm/i915/i915_reg.h | 5 +++-- > 2 files changed, 7 insertions(+), 2 deletions(-) > > diff --git a/drivers/gpu/drm/i915/display/intel_display.c > b/drivers/gpu/drm/i915/display/intel_display.c > index 0ceee8ac6671..5d50d06f4eb7 100644 > --- a/drivers/gpu/drm/i915/display/intel_display.c > +++ b/drivers/gpu/drm/i915/display/intel_display.c > @@ -988,6 +988,10 @@ static void icl_set_pipe_chicken(const struct > intel_crtc_state *crtc_state) > else if (DISPLAY_VER(dev_priv) >= 13) > tmp |= UNDERRUN_RECOVERY_DISABLE_ADLP; > > + /* Wa_14010547955:dg2 */ > + if (IS_DG2_DISP_STEP(dev_priv, STEP_B0, STEP_FOREVER))
How did we end up with _DISP_ for DG2 when everything else has _DISPLAY_? BR, Jani. > + tmp |= DG2_RENDER_CCSTAG_4_3_EN; > + > intel_de_write(dev_priv, PIPE_CHICKEN(pipe), tmp); > } > > diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h > index 07d6cf76c389..680ace373e00 100644 > --- a/drivers/gpu/drm/i915/i915_reg.h > +++ b/drivers/gpu/drm/i915/i915_reg.h > @@ -8480,8 +8480,9 @@ enum { > _PIPEB_CHICKEN) > #define UNDERRUN_RECOVERY_DISABLE_ADLP REG_BIT(30) > #define UNDERRUN_RECOVERY_ENABLE_DG2 REG_BIT(30) > -#define PIXEL_ROUNDING_TRUNC_FB_PASSTHRU (1 << 15) > -#define PER_PIXEL_ALPHA_BYPASS_EN (1 << 7) > +#define PIXEL_ROUNDING_TRUNC_FB_PASSTHRU REG_BIT(15) > +#define DG2_RENDER_CCSTAG_4_3_EN REG_BIT(12) > +#define PER_PIXEL_ALPHA_BYPASS_EN REG_BIT(7) > > #define FF_MODE2 _MMIO(0x6604) > #define FF_MODE2_GS_TIMER_MASK REG_GENMASK(31, 24) -- Jani Nikula, Intel Open Source Graphics Center