From 7e812f2e9cdac80f6287d4aee5deb434597c4f8b Mon Sep 17 00:00:00 2001 From: Thomas Chou Date: Sat, 17 Apr 2010 23:34:40 +0800 Subject: [PATCH] nios2: add dma_alloc_coherent This function return cache-line aligned allocation which is mapped to uncached io region. Signed-off-by: Thomas Chou Signed-off-by: Scott McNutt --- arch/nios2/include/asm/dma-mapping.h | 23 +++++++++++++++++++++++ 1 file changed, 23 insertions(+) create mode 100644 arch/nios2/include/asm/dma-mapping.h diff --git a/arch/nios2/include/asm/dma-mapping.h b/arch/nios2/include/asm/dma-mapping.h new file mode 100644 index 0000000000..1350e3b96f --- /dev/null +++ b/arch/nios2/include/asm/dma-mapping.h @@ -0,0 +1,23 @@ +#ifndef __ASM_NIOS2_DMA_MAPPING_H +#define __ASM_NIOS2_DMA_MAPPING_H + +/* dma_alloc_coherent() return cache-line aligned allocation which is mapped + * to uncached io region. + * + * IO_REGION_BASE should be defined in board config header file + * 0x80000000 for nommu, 0xe0000000 for mmu + */ + +static inline void *dma_alloc_coherent(size_t len, unsigned long *handle) +{ + void *addr = malloc(len + CONFIG_SYS_DCACHELINE_SIZE); + if (!addr) + return 0; + flush_dcache((unsigned long)addr, len + CONFIG_SYS_DCACHELINE_SIZE); + *handle = ((unsigned long)addr + + (CONFIG_SYS_DCACHELINE_SIZE - 1)) & + ~(CONFIG_SYS_DCACHELINE_SIZE - 1) & ~(IO_REGION_BASE); + return (void *)(*handle | IO_REGION_BASE); +} + +#endif /* __ASM_NIOS2_DMA_MAPPING_H */ -- 2.39.2