On Tue, Aug 22, 2023 at 11:28:59AM -0400, Oak Zeng wrote: > From: Nirmoy Das <[email protected]> > > MTL can hang because of a HW bug while parallel reading/writing > from/to LMEM/GTTMMADR BAR so try to reduce GGTT update > related pci transactions with blitter command as recommended > for Wa_22018444074.
Drive-by comment: this isn't a valid workaround number. 22018444074 is a per-platform record number, whereas workarounds should always be identified by their cross-platform lineage number, which will stay constant if the workaround winds up extending to future platforms as well. So in this case, the workaround should be referred to as Wa_13010847436. Matt > > To issue blitter commands, the driver must be primed to receive > requests. Maintain blitter-based GGTT update disablement until driver > probing completes. Moreover, implement a temporary disablement > of blitter prior to entering suspend, followed by re-enablement > post-resume. This is acceptable as those transition periods are > mostly single threaded. > > v2: Disable GGTT blitter prior to runtime suspend and re-enable > after runtime resume. (Oak) > > Signed-off-by: Nirmoy Das <[email protected]> > Signed-off-by: Oak Zeng <[email protected]> > --- > drivers/gpu/drm/i915/i915_driver.c | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/drivers/gpu/drm/i915/i915_driver.c > b/drivers/gpu/drm/i915/i915_driver.c > index f8dbee7a5af7..6afe0adc8ddb 100644 > --- a/drivers/gpu/drm/i915/i915_driver.c > +++ b/drivers/gpu/drm/i915/i915_driver.c > @@ -815,6 +815,7 @@ int i915_driver_probe(struct pci_dev *pdev, const struct > pci_device_id *ent) > i915_welcome_messages(i915); > > i915->do_release = true; > + intel_engine_blitter_context_set_ready(to_gt(i915), true); > > return 0; > > @@ -855,6 +856,7 @@ void i915_driver_remove(struct drm_i915_private *i915) > { > intel_wakeref_t wakeref; > > + intel_engine_blitter_context_set_ready(to_gt(i915), false); > wakeref = intel_runtime_pm_get(&i915->runtime_pm); > > i915_driver_unregister(i915); > @@ -1077,6 +1079,8 @@ static int i915_drm_suspend(struct drm_device *dev) > struct pci_dev *pdev = to_pci_dev(dev_priv->drm.dev); > pci_power_t opregion_target_state; > > + intel_engine_blitter_context_set_ready(to_gt(dev_priv), false); > + > disable_rpm_wakeref_asserts(&dev_priv->runtime_pm); > > /* We do a lot of poking in a lot of registers, make sure they work > @@ -1264,6 +1268,7 @@ static int i915_drm_resume(struct drm_device *dev) > intel_gvt_resume(dev_priv); > > enable_rpm_wakeref_asserts(&dev_priv->runtime_pm); > + intel_engine_blitter_context_set_ready(to_gt(dev_priv), true); > > return 0; > } > @@ -1515,6 +1520,7 @@ static int intel_runtime_suspend(struct device *kdev) > if (drm_WARN_ON_ONCE(&dev_priv->drm, !HAS_RUNTIME_PM(dev_priv))) > return -ENODEV; > > + intel_engine_blitter_context_set_ready(to_gt(dev_priv), false); > drm_dbg(&dev_priv->drm, "Suspending device\n"); > > disable_rpm_wakeref_asserts(rpm); > @@ -1669,6 +1675,8 @@ static int intel_runtime_resume(struct device *kdev) > else > drm_dbg(&dev_priv->drm, "Device resumed\n"); > > + intel_engine_blitter_context_set_ready(to_gt(dev_priv), true); > + > return ret; > } > > -- > 2.26.3 > -- Matt Roper Graphics Software Engineer Linux GPU Platform Enablement Intel Corporation
