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 #include <linux/export.h> 16 17 #include <asm/pgalloc.h> 18 19 #if defined(CONFIG_MMU) && !defined(CONFIG_COLDFIRE) 20 21 static void *m68k_dma_alloc(struct device *dev, size_t size, dma_addr_t *handle, 22 gfp_t flag, unsigned long attrs) 23 { 24 struct page *page, **map; 25 pgprot_t pgprot; 26 void *addr; 27 int i, order; 28 29 pr_debug("dma_alloc_coherent: %d,%x\n", size, flag); 30 31 size = PAGE_ALIGN(size); 32 order = get_order(size); 33 34 page = alloc_pages(flag, order); 35 if (!page) 36 return NULL; 37 38 *handle = page_to_phys(page); 39 map = kmalloc(sizeof(struct page *) << order, flag & ~__GFP_DMA); 40 if (!map) { 41 __free_pages(page, order); 42 return NULL; 43 } 44 split_page(page, order); 45 46 order = 1 << order; 47 size >>= PAGE_SHIFT; 48 map[0] = page; 49 for (i = 1; i < size; i++) 50 map[i] = page + i; 51 for (; i < order; i++) 52 __free_page(page + i); 53 pgprot = __pgprot(_PAGE_PRESENT | _PAGE_ACCESSED | _PAGE_DIRTY); 54 if (CPU_IS_040_OR_060) 55 pgprot_val(pgprot) |= _PAGE_GLOBAL040 | _PAGE_NOCACHE_S; 56 else 57 pgprot_val(pgprot) |= _PAGE_NOCACHE030; 58 addr = vmap(map, size, VM_MAP, pgprot); 59 kfree(map); 60 61 return addr; 62 } 63 64 static void m68k_dma_free(struct device *dev, size_t size, void *addr, 65 dma_addr_t handle, unsigned long attrs) 66 { 67 pr_debug("dma_free_coherent: %p, %x\n", addr, handle); 68 vfree(addr); 69 } 70 71 #else 72 73 #include <asm/cacheflush.h> 74 75 static void *m68k_dma_alloc(struct device *dev, size_t size, 76 dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs) 77 { 78 void *ret; 79 80 if (dev == NULL || (*dev->dma_mask < 0xffffffff)) 81 gfp |= GFP_DMA; 82 ret = (void *)__get_free_pages(gfp, get_order(size)); 83 84 if (ret != NULL) { 85 memset(ret, 0, size); 86 *dma_handle = virt_to_phys(ret); 87 } 88 return ret; 89 } 90 91 static void m68k_dma_free(struct device *dev, size_t size, void *vaddr, 92 dma_addr_t dma_handle, unsigned long attrs) 93 { 94 free_pages((unsigned long)vaddr, get_order(size)); 95 } 96 97 #endif /* CONFIG_MMU && !CONFIG_COLDFIRE */ 98 99 static void m68k_dma_sync_single_for_device(struct device *dev, 100 dma_addr_t handle, size_t size, enum dma_data_direction dir) 101 { 102 switch (dir) { 103 case DMA_BIDIRECTIONAL: 104 case DMA_TO_DEVICE: 105 cache_push(handle, size); 106 break; 107 case DMA_FROM_DEVICE: 108 cache_clear(handle, size); 109 break; 110 default: 111 pr_err_ratelimited("dma_sync_single_for_device: unsupported dir %u\n", 112 dir); 113 break; 114 } 115 } 116 117 static void m68k_dma_sync_sg_for_device(struct device *dev, 118 struct scatterlist *sglist, int nents, enum dma_data_direction dir) 119 { 120 int i; 121 struct scatterlist *sg; 122 123 for_each_sg(sglist, sg, nents, i) { 124 dma_sync_single_for_device(dev, sg->dma_address, sg->length, 125 dir); 126 } 127 } 128 129 static dma_addr_t m68k_dma_map_page(struct device *dev, struct page *page, 130 unsigned long offset, size_t size, enum dma_data_direction dir, 131 unsigned long attrs) 132 { 133 dma_addr_t handle = page_to_phys(page) + offset; 134 135 if (!(attrs & DMA_ATTR_SKIP_CPU_SYNC)) 136 dma_sync_single_for_device(dev, handle, size, dir); 137 138 return handle; 139 } 140 141 static int m68k_dma_map_sg(struct device *dev, struct scatterlist *sglist, 142 int nents, enum dma_data_direction dir, unsigned long attrs) 143 { 144 int i; 145 struct scatterlist *sg; 146 147 for_each_sg(sglist, sg, nents, i) { 148 sg->dma_address = sg_phys(sg); 149 150 if (attrs & DMA_ATTR_SKIP_CPU_SYNC) 151 continue; 152 153 dma_sync_single_for_device(dev, sg->dma_address, sg->length, 154 dir); 155 } 156 return nents; 157 } 158 159 const struct dma_map_ops m68k_dma_ops = { 160 .alloc = m68k_dma_alloc, 161 .free = m68k_dma_free, 162 .map_page = m68k_dma_map_page, 163 .map_sg = m68k_dma_map_sg, 164 .sync_single_for_device = m68k_dma_sync_single_for_device, 165 .sync_sg_for_device = m68k_dma_sync_sg_for_device, 166 }; 167 EXPORT_SYMBOL(m68k_dma_ops); 168