diff options
Diffstat (limited to 'arch/nios2/include/asm/dma-mapping.h')
-rw-r--r-- | arch/nios2/include/asm/dma-mapping.h | 25 |
1 files changed, 25 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 0000000000..49ebf798af --- /dev/null +++ b/arch/nios2/include/asm/dma-mapping.h @@ -0,0 +1,25 @@ +#ifndef __ASM_NIOS2_DMA_MAPPING_H +#define __ASM_NIOS2_DMA_MAPPING_H + +#include <asm/cache.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 + DCACHE_LINE_SIZE); + if (!addr) + return 0; + flush_dcache_range((unsigned long)addr, len + DCACHE_LINE_SIZE); + *handle = ((unsigned long)addr + + (DCACHE_LINE_SIZE - 1)) & + ~(DCACHE_LINE_SIZE - 1) & ~(IO_REGION_BASE); + return (void *)(*handle | IO_REGION_BASE); +} + +#endif /* __ASM_NIOS2_DMA_MAPPING_H */ |