Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * Dynamic DMA mapping support. |
| 3 | * |
| 4 | * We never have any address translations to worry about, so this |
| 5 | * is just alloc/free. |
| 6 | */ |
| 7 | |
| 8 | #include <linux/types.h> |
| 9 | #include <linux/mm.h> |
| 10 | #include <linux/string.h> |
Greg Ungerer | 85e026b | 2007-07-25 22:07:20 +1000 | [diff] [blame] | 11 | #include <linux/device.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 12 | #include <asm/io.h> |
| 13 | |
| 14 | void *dma_alloc_coherent(struct device *dev, size_t size, |
| 15 | dma_addr_t *dma_handle, int gfp) |
| 16 | { |
| 17 | void *ret; |
| 18 | /* ignore region specifiers */ |
| 19 | gfp &= ~(__GFP_DMA | __GFP_HIGHMEM); |
| 20 | |
| 21 | if (dev == NULL || (*dev->dma_mask < 0xffffffff)) |
| 22 | gfp |= GFP_DMA; |
| 23 | ret = (void *)__get_free_pages(gfp, get_order(size)); |
| 24 | |
| 25 | if (ret != NULL) { |
| 26 | memset(ret, 0, size); |
| 27 | *dma_handle = virt_to_phys(ret); |
| 28 | } |
| 29 | return ret; |
| 30 | } |
| 31 | |
| 32 | void dma_free_coherent(struct device *dev, size_t size, |
| 33 | void *vaddr, dma_addr_t dma_handle) |
| 34 | { |
| 35 | free_pages((unsigned long)vaddr, get_order(size)); |
| 36 | } |