On Thu, Aug 04, 2016 at 09:57:11AM +0300, Ville Syrjälä wrote: > On Wed, Aug 03, 2016 at 05:16:42PM +0100, Chris Wilson wrote: > > Erratum SKL075: Display Flicker May Occur When Both VT-d And FBC Are Enabled > > > > "Display flickering may occur when both FBC (Frame Buffer Compression) > > and VT - d (Intel® Virtualization Technology for Directed I/O) are enabled > > and in use by the display controller." > > > > Ville found the w/a name in the database: > > WaFbcTurnOffFbcWhenHyperVisorIsUsed:skl > > > > v2: Log when the quirk is applied. > > v3: Ensure i915.enable_fbc is false when !HAS_FBC() > > v4: Fix function name after rebase > > > > Signed-off-by: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> > > Cc: Paulo Zanoni <paulo.r.zanoni@xxxxxxxxx> > > Cc: Ville Syrjälä <ville.syrjala@xxxxxxxxxxxxxxx> > > --- > > drivers/gpu/drm/i915/intel_fbc.c | 19 +++++++++++++++++++ > > 1 file changed, 19 insertions(+) > > > > diff --git a/drivers/gpu/drm/i915/intel_fbc.c b/drivers/gpu/drm/i915/intel_fbc.c > > index 8147eb9e8475..b673c7c54a46 100644 > > --- a/drivers/gpu/drm/i915/intel_fbc.c > > +++ b/drivers/gpu/drm/i915/intel_fbc.c > > @@ -1229,12 +1229,28 @@ static int intel_sanitize_fbc_option(struct drm_i915_private *dev_priv) > > if (i915.enable_fbc >= 0) > > return !!i915.enable_fbc; > > > > + if (!HAS_FBC(dev_priv)) > > + return 0; > > + > > if (IS_BROADWELL(dev_priv)) > > return 1; > > > > return 0; > > } > > > > +static bool need_fbc_wa(struct drm_i915_private *dev_priv) > > need_fbc_vtd_wa() perhaps? Right now, yes. I left it open just in case - but that's most likely a false hope. > > +{ > > +#ifdef CONFIG_INTEL_IOMMU > > + /* WaFbcTurnOffFbcWhenHyperVisorIsUsed:skl */ > > + if (intel_iommu_gfx_mapped && IS_SKYLAKE(dev_priv)) { > > BXT needs this as well AFAICS. Will IS_GEN9() suit? +skl,bxt in the description. -Chris -- Chris Wilson, Intel Open Source Technology Centre _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx