1/* 2 * This file is subject to the terms and conditions of the GNU General Public 3 * License. See the file COPYING in the main directory of this archive 4 * for more details. 5 */ 6 7#undef DEBUG 8 9#include <linux/dma-mapping.h> 10#include <linux/device.h> 11#include <linux/kernel.h> 12#include <linux/scatterlist.h> 13#include <linux/slab.h> 14#include <linux/vmalloc.h> 15 16#include <asm/pgalloc.h> 17 18void *dma_alloc_coherent(struct device *dev, size_t size, 19 dma_addr_t *handle, gfp_t flag) 20{ 21 struct page *page, **map; 22 pgprot_t pgprot; 23 void *addr; 24 int i, order; 25 26 pr_debug("dma_alloc_coherent: %d,%x\n", size, flag); 27 28 size = PAGE_ALIGN(size); 29 order = get_order(size); 30 31 page = alloc_pages(flag, order); 32 if (!page) 33 return NULL; 34 35 *handle = page_to_phys(page); 36 map = kmalloc(sizeof(struct page *) << order, flag & ~__GFP_DMA); 37 if (!map) { 38 __free_pages(page, order); 39 return NULL; 40 } 41 split_page(page, order); 42 43 order = 1 << order; 44 size >>= PAGE_SHIFT; 45 map[0] = page; 46 for (i = 1; i < size; i++) 47 map[i] = page + i; 48 for (; i < order; i++) 49 __free_page(page + i); 50 pgprot = __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY); 51 if (CPU_IS_040_OR_060) 52 pgprot_val(pgprot) |= _PAGE_GLOBAL040 | _PAGE_NOCACHE_S; 53 else 54 pgprot_val(pgprot) |= _PAGE_NOCACHE030; 55 addr = vmap(map, size, VM_MAP, pgprot); 56 kfree(map); 57 58 return addr; 59} 60EXPORT_SYMBOL(dma_alloc_coherent); 61 62void dma_free_coherent(struct device *dev, size_t size, 63 void *addr, dma_addr_t handle) 64{ 65 pr_debug("dma_free_coherent: %p, %x\n", addr, handle); 66 vfree(addr); 67} 68EXPORT_SYMBOL(dma_free_coherent); 69 70void dma_sync_single_for_device(struct device *dev, dma_addr_t handle, 71 size_t size, enum dma_data_direction dir) 72{ 73 switch (dir) { 74 case DMA_TO_DEVICE: 75 cache_push(handle, size); 76 break; 77 case DMA_FROM_DEVICE: 78 cache_clear(handle, size); 79 break; 80 default: 81 if (printk_ratelimit()) 82 printk("dma_sync_single_for_device: unsupported dir %u\n", dir); 83 break; 84 } 85} 86EXPORT_SYMBOL(dma_sync_single_for_device); 87 88void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nents, 89 enum dma_data_direction dir) 90{ 91 int i; 92 93 for (i = 0; i < nents; sg++, i++) 94 dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir); 95} 96EXPORT_SYMBOL(dma_sync_sg_for_device); 97 98dma_addr_t dma_map_single(struct device *dev, void *addr, size_t size, 99 enum dma_data_direction dir) 100{ 101 dma_addr_t handle = virt_to_bus(addr); 102 103 dma_sync_single_for_device(dev, handle, size, dir); 104 return handle; 105} 106EXPORT_SYMBOL(dma_map_single); 107 108dma_addr_t dma_map_page(struct device *dev, struct page *page, 109 unsigned long offset, size_t size, 110 enum dma_data_direction dir) 111{ 112 dma_addr_t handle = page_to_phys(page) + offset; 113 114 dma_sync_single_for_device(dev, handle, size, dir); 115 return handle; 116} 117EXPORT_SYMBOL(dma_map_page); 118 119int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents, 120 enum dma_data_direction dir) 121{ 122 int i; 123 124 for (i = 0; i < nents; sg++, i++) { 125 sg->dma_address = sg_phys(sg); 126 dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir); 127 } 128 return nents; 129} 130EXPORT_SYMBOL(dma_map_sg); 131