1/* 2 * Dynamic DMA mapping support. 3 * 4 * On cris there is no hardware dynamic DMA address translation, 5 * so consistent alloc/free are merely page allocation/freeing. 6 * The rest of the dynamic DMA mapping interface is implemented 7 * in asm/pci.h. 8 * 9 * Borrowed from i386. 10 */ 11 12#include <linux/types.h> 13#include <linux/mm.h> 14#include <linux/string.h> 15#include <linux/pci.h> 16#include <linux/gfp.h> 17#include <asm/io.h> 18 19void *dma_alloc_coherent(struct device *dev, size_t size, 20 dma_addr_t *dma_handle, gfp_t gfp) 21{ 22 void *ret; 23 int order = get_order(size); 24 /* ignore region specifiers */ 25 gfp &= ~(__GFP_DMA | __GFP_HIGHMEM); 26 27 if (dma_alloc_from_coherent(dev, size, dma_handle, &ret)) 28 return ret; 29 30 if (dev == NULL || (dev->coherent_dma_mask < 0xffffffff)) 31 gfp |= GFP_DMA; 32 33 ret = (void *)__get_free_pages(gfp, order); 34 35 if (ret != NULL) { 36 memset(ret, 0, size); 37 *dma_handle = virt_to_phys(ret); 38 } 39 return ret; 40} 41 42void dma_free_coherent(struct device *dev, size_t size, 43 void *vaddr, dma_addr_t dma_handle) 44{ 45 int order = get_order(size); 46 47 if (!dma_release_from_coherent(dev, order, vaddr)) 48 free_pages((unsigned long)vaddr, order); 49} 50