On Tue, Jul 07, 2015 at 12:04:10AM +0800, Zhi Wang wrote: > Hi Chris and Mika: > Thanks for the comments. I think that reset HW on module unload > is an good idea. For now I think we should choose a proper position > in the module unload sequence to reset HW. As GPU reset is render > engine reset plus ring imrs(They will become to alll F after full > GPU reset), I think a proper position should be after render and > interrupt shutdown path. > > How about this place? > > diff --git a/drivers/gpu/drm/i915/i915_dma.c > b/drivers/gpu/drm/i915/i915_dma.c > index c5349fa..aeaf59e 100644 > --- a/drivers/gpu/drm/i915/i915_dma.c > +++ b/drivers/gpu/drm/i915/i915_dma.c > @@ -1133,7 +1133,10 @@ int i915_driver_unload(struct drm_device *dev) > pm_qos_remove_request(&dev_priv->pm_qos); > > i915_global_gtt_cleanup(dev); > - > + /* The only known way to stop the gpu from accessing the hw > context is > + * to reset it. Do this as the very last operation to avoid > confusing > + * other code, leading to spurious errors. */ > + intel_gpu_reset(dev); That feels right. The comment is out-of-place now and needs expansion to include other side effects for which the gpu reset is meritted. But this is a riskier patch since we now start doing unconditional resets for gen3-gen5. Just requires more soak testing, but I would prefer it as (1) add execlists reset, (2) combine execlists reset + power context reset into a single unload reset. That way if we do get a regression in doing the unload reset we can revert back to execlists easily. -Chris -- Chris Wilson, Intel Open Source Technology Centre _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx http://lists.freedesktop.org/mailman/listinfo/intel-gfx
