On Thu, Jan 15, 2015 at 08:30:06AM +0000, Thierry Reding wrote: > On Wed, Jan 14, 2015 at 07:17:50PM +0000, Will Deacon wrote: > > On Wed, Jan 14, 2015 at 01:51:36PM +0000, Heiko Stübner wrote: > > > As Alexandre suspected the new Rockchip drm code seems to be affected by > > > this. I hadn't played with the drm code before last weekend and was then > > > stumbling over different iommu related issues. As I hadn't to much contact > > > with iommus till now I didn't get very far. > > > > > > But with Alexandre's bandaid patch of adding > > > set_dma_ops(dev, &iommu_ops); > > > to arm_iommu_attach_device both problems go away. > > > > > > > > > So to elaborate on the two failure cases: > > > > Aha, I see what you mean now -- the issue is that attaching to an IOMMU > > domain no longer swizzles the DMA ops. Furthermore, we also need to take > > into account the coherency of the device, which we didn't do before (and > > assumedly "worked" because all of the users happened to be non-coherent). > > > > Maybe we just need to add something like arm_iommu_swizzle_dma_ops, so > > that direct users of the arm_iommu_* API can manage things manually? > > Why does this even have to be an ARM-specific API? Couldn't this equally > well be generic across all platforms so that we get unified handling of > IOMMU through the DMA API?
It's already an ARM-specific API. Having something generic would be great, but I was thinking more about a short-term fix for the current issue rather than implementing something brand new. Will _______________________________________________ iommu mailing list iommu@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/iommu
