Quoting Mika Kuoppala (2018-06-05 17:03:57) > There is a problem with kbl up to rev E0 where a heavy > memory/fabric traffic from adjacent engine(s) can cause an engine > reset to fail. This traffic can be from normal memory accesses > or it can be from heavy polling on a semaphore wait. > > For engine hogging causing a fail, we already fallback to > full reset. Which effectively stops all engines and thus > we only add a workaround documentation. > > For the semaphore wait loop poll case, we add one microsecond > poll interval to semaphore wait to guarantee bandwidth for > the reset preration. The side effect is that we make semaphore > completion latencies also 1us longer. > > v2: Let full reset handle the adjacent engine idling (Chris) > > References: https://bugs.freedesktop.org/show_bug.cgi?id=106684 > References: VTHSD#2227190, HSDES#1604216706, BSID#0917 > Signed-off-by: Mika Kuoppala <mika.kuoppala@xxxxxxxxxxxxxxx> > --- > diff --git a/drivers/gpu/drm/i915/intel_workarounds.c b/drivers/gpu/drm/i915/intel_workarounds.c > index b1ab56a1ec31..5655d39c65cb 100644 > --- a/drivers/gpu/drm/i915/intel_workarounds.c > +++ b/drivers/gpu/drm/i915/intel_workarounds.c > @@ -666,6 +666,15 @@ static void kbl_gt_workarounds_apply(struct drm_i915_private *dev_priv) > I915_WRITE(GEN9_GAMT_ECO_REG_RW_IA, > I915_READ(GEN9_GAMT_ECO_REG_RW_IA) | > GAMT_ECO_ENABLE_IN_PLACE_DECOMPRESS); > + > + /* WaKBLVECSSemaphoreWaitPoll:kbl */ > + if (IS_KBL_REVID(dev_priv, KBL_REVID_A0, KBL_REVID_E0)) { Hmm, what revision was production? Just checking we need to ship this w/a... -Chris _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx
