On Tue, Mar 07, 2017 at 06:43:32PM +0100, Geert Uytterhoeven wrote: > Add support for allocating physically contiguous DMA buffers on arm64 > systems with an IOMMU. This can be useful when two or more devices > with different memory requirements are involved in buffer sharing. > > Note that as this uses the CMA allocator, setting the > DMA_ATTR_FORCE_CONTIGUOUS attribute has a runtime-dependency on > CONFIG_DMA_CMA, just like on arm32. > > For arm64 systems using swiotlb, no changes are needed to support the > allocation of physically contiguous DMA buffers: > - swiotlb always uses physically contiguous buffers (up to > IO_TLB_SEGSIZE = 128 pages), > - arm64's __dma_alloc_coherent() already calls > dma_alloc_from_contiguous() when CMA is available. > > Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx> > Acked-by: Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx> > Reviewed-by: Robin Murphy <robin.murphy@xxxxxxx> Queued for 4.12. Thanks. -- Catalin
