On 4/11/22 16:46, Robin Murphy wrote: > @@ -1092,6 +1092,19 @@ static bool host1x_drm_wants_iommu(struct host1x_device *dev) > struct host1x *host1x = dev_get_drvdata(dev->dev.parent); > struct iommu_domain *domain; > > + /* For starters, this is moot if no IOMMU is available */ > + if (!device_iommu_mapped(&dev->dev)) > + return false; Unfortunately this returns false on T30 with enabled IOMMU because we don't use IOMMU for Host1x on T30 [1] to optimize performance. We can't change it until we will update drivers to support Host1x-dedicated buffers. [1] https://elixir.bootlin.com/linux/latest/source/drivers/gpu/host1x/dev.c#L258 -- Best regards, Dmitry
