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Still, ARM's own DMA code is kept t= o > > support existing drivers and APIs that expect it, and because dma-iommu > > is considered too big and unnecessary for 32-bit ARM. >=20 > Now that the different domain handling is gone, what speaks against > just using the generic dma-iommu code for arm32? >=20 >=20 Copying Robin's comment -- > TBH I rather feel like the time for converting ARM to iommu-dma has=20 > passed - there are drivers which rely on specific behaviours of the ARM=20 > IOVA allocator which iommu-dma does not match, and meanwhile iommu-dma=20 > continues to grow more server-specific features which would be nothing=20 > but bloat on ARMv7 systems with <=3D2GB of RAM and no virtualisation. At= =20 > this point I'm inclined to treat the existing DMA ops as legacy code=20 > like with alpha/sparc/etc. Aside the bloat, it's indeed not a switch we could do in the short term=20 given all the platforms that rely on ARM32 specific APIs or behavior.=20 This series already opts out four platforms from just the default=20 domains and sashiko implies we need to add more to that list. There=20 could be an incremental path of removing existing hacky behavior and if=20 we manage that, eventually code sharing could be considered. Mikko