diff options
| author | Thomas Chou <thomas@wytron.com.tw> | 2010-04-17 23:34:40 +0800 |
|---|---|---|
| committer | Scott McNutt <smcnutt@psyent.com> | 2010-04-24 18:21:22 -0400 |
| commit | 7e812f2e9cdac80f6287d4aee5deb434597c4f8b (patch) | |
| tree | eb35187ca13557946626ddfdf0837515501d3fb8 /arch | |
| parent | 0dc1c7f692c15fe1745e3eeab918e98ee6126677 (diff) | |
nios2: add dma_alloc_coherent
This function return cache-line aligned allocation which is mapped
to uncached io region.
Signed-off-by: Thomas Chou <thomas@wytron.com.tw>
Signed-off-by: Scott McNutt <smcnutt@psyent.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/nios2/include/asm/dma-mapping.h | 23 |
1 files changed, 23 insertions, 0 deletions
diff --git a/arch/nios2/include/asm/dma-mapping.h b/arch/nios2/include/asm/dma-mapping.h new file mode 100644 index 00000000000..1350e3b96fd --- /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 */ |