dma-mapping: remove arch_dma_mmap_pgprot
arch_dma_mmap_pgprot is used for two things:
1) to override the "normal" uncached page attributes for mapping
memory coherent to devices that can't snoop the CPU caches
2) to provide the special DMA_ATTR_WRITE_COMBINE semantics on older
arm systems and some mips platforms
Replace one with the pgprot_dmacoherent macro that is already provided
by arm and much simpler to use, and lift the DMA_ATTR_WRITE_COMBINE
handling to common code with an explicit arch opt-in.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k
Acked-by: Paul Burton <paul.burton@mips.com> # mips
diff --git a/arch/mips/Kconfig b/arch/mips/Kconfig
index d50fafd..fc88f68 100644
--- a/arch/mips/Kconfig
+++ b/arch/mips/Kconfig
@@ -1119,7 +1119,7 @@
config DMA_NONCOHERENT
bool
- select ARCH_HAS_DMA_MMAP_PGPROT
+ select ARCH_HAS_DMA_WRITE_COMBINE
select ARCH_HAS_SYNC_DMA_FOR_DEVICE
select ARCH_HAS_UNCACHED_SEGMENT
select NEED_DMA_MAP_STATE
