kernel/include/linux/dma-noncoherent.h, branch linux-5.1.y

dma-mapping: bypass indirect calls for dma-direct

2018-12-13T20:06:18Z

Avoid expensive indirect calls in the fast path DMA mapping operations by directly calling the dma_direct_* ops if we are using the directly mapped DMA operations. Signed-off-by: Christoph Hellwig Acked-by: Jesper Dangaard Brouer Tested-by: Jesper Dangaard Brouer Tested-by: Tony Luck

dma-mapping: move the arm64 noncoherent alloc/free support to common code

2018-12-01T17:07:11Z

The arm64 codebase to implement coherent dma allocation for architectures with non-coherent DMA is a good start for a generic implementation, given that is uses the generic remap helpers, provides the atomic pool for allocations that can't sleep and still is realtively simple and well tested. Move it to kernel/dma and allow architectures to opt into it using a config symbol. Architectures just need to provide a new arch_dma_prep_coherent helper to writeback an invalidate the caches for any memory that gets remapped for uncached access. Signed-off-by: Christoph Hellwig Reviewed-by: Will Deacon Reviewed-by: Robin Murphy

dma-mapping: consolidate the dma mmap implementations

2018-09-20T07:01:16Z

The only functional differences (modulo a few missing fixes in the arch code) is that architectures without coherent caches need a hook to convert a virtual or dma address into a pfn, given that we don't have the kernel linear mapping available for the otherwise easy virt_to_page call. As a side effect we can support mmap of the per-device coherent area even on architectures not providing the callback, and we make previous dangerous default methods dma_common_mmap actually save for non-coherent architectures by rejecting it without the right helper. In addition to that we need a hook so that some architectures can override the protection bits when mmaping a dma coherent allocations. Signed-off-by: Christoph Hellwig Acked-by: Paul Burton # MIPS parts

dma-mapping: merge direct and noncoherent ops

2018-09-20T07:01:15Z

All the cache maintainance is already stubbed out when not enabled, but merging the two allows us to nicely handle the case where cache maintainance is required for some devices, but not others. Signed-off-by: Christoph Hellwig Acked-by: Paul Burton # MIPS parts

dma-mapping: move the dma_coherent flag to struct device

2018-09-20T07:01:15Z

Various architectures support both coherent and non-coherent dma on a per-device basis. Move the dma_noncoherent flag from the mips archdata field to struct device proper to prepare the infrastructure for reuse on other architectures. Signed-off-by: Christoph Hellwig Acked-by: Paul Burton Acked-by: Greg Kroah-Hartman

dma-noncoherent: add a arch_sync_dma_for_cpu_all hook

2018-06-24T16:27:27Z

The MIPS bmips platform needs a global flush when transferring ownership back to the CPU. Add a hook for that to the dma-noncoherent implementation. Signed-off-by: Christoph Hellwig Patchwork: https://patchwork.linux-mips.org/patch/19549/ Signed-off-by: Paul Burton Cc: Florian Fainelli Cc: David Daney Cc: Kevin Cernekee Cc: Jiaxun Yang Cc: Tom Bogendoerfer Cc: Huacai Chen Cc: iommu@lists.linux-foundation.org Cc: linux-mips@linux-mips.org

dma-mapping: provide a generic dma-noncoherent implementation

2018-05-19T06:46:12Z

Add a new dma_map_ops implementation that uses dma-direct for the address mapping of streaming mappings, and which requires arch-specific implemenations of coherent allocate/free. Architectures have to provide flushing helpers to ownership trasnfers to the device and/or CPU, and can provide optional implementations of the coherent mmap functionality, and the cache_flush routines for non-coherent long term allocations. Signed-off-by: Christoph Hellwig Tested-by: Alexey Brodkin Acked-by: Vineet Gupta