1
2
3
4
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
21void *dma_alloc_coherent(struct device *dev, size_t size,
22 dma_addr_t *handle, gfp_t flag)
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
64void dma_free_coherent(struct device *dev, size_t size,
65 void *addr, dma_addr_t handle)
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
75void *dma_alloc_coherent(struct device *dev, size_t size,
76 dma_addr_t *dma_handle, gfp_t gfp)
77{
78 void *ret;
79
80 gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
81
82 if (dev == NULL || (*dev->dma_mask < 0xffffffff))
83 gfp |= GFP_DMA;
84 ret = (void *)__get_free_pages(gfp, get_order(size));
85
86 if (ret != NULL) {
87 memset(ret, 0, size);
88 *dma_handle = virt_to_phys(ret);
89 }
90 return ret;
91}
92
93void dma_free_coherent(struct device *dev, size_t size,
94 void *vaddr, dma_addr_t dma_handle)
95{
96 free_pages((unsigned long)vaddr, get_order(size));
97}
98
99#endif
100
101EXPORT_SYMBOL(dma_alloc_coherent);
102EXPORT_SYMBOL(dma_free_coherent);
103
104void dma_sync_single_for_device(struct device *dev, dma_addr_t handle,
105 size_t size, enum dma_data_direction dir)
106{
107 switch (dir) {
108 case DMA_BIDIRECTIONAL:
109 case DMA_TO_DEVICE:
110 cache_push(handle, size);
111 break;
112 case DMA_FROM_DEVICE:
113 cache_clear(handle, size);
114 break;
115 default:
116 if (printk_ratelimit())
117 printk("dma_sync_single_for_device: unsupported dir %u\n", dir);
118 break;
119 }
120}
121EXPORT_SYMBOL(dma_sync_single_for_device);
122
123void dma_sync_sg_for_device(struct device *dev, struct scatterlist *sg, int nents,
124 enum dma_data_direction dir)
125{
126 int i;
127
128 for (i = 0; i < nents; sg++, i++)
129 dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir);
130}
131EXPORT_SYMBOL(dma_sync_sg_for_device);
132
133dma_addr_t dma_map_single(struct device *dev, void *addr, size_t size,
134 enum dma_data_direction dir)
135{
136 dma_addr_t handle = virt_to_bus(addr);
137
138 dma_sync_single_for_device(dev, handle, size, dir);
139 return handle;
140}
141EXPORT_SYMBOL(dma_map_single);
142
143dma_addr_t dma_map_page(struct device *dev, struct page *page,
144 unsigned long offset, size_t size,
145 enum dma_data_direction dir)
146{
147 dma_addr_t handle = page_to_phys(page) + offset;
148
149 dma_sync_single_for_device(dev, handle, size, dir);
150 return handle;
151}
152EXPORT_SYMBOL(dma_map_page);
153
154int dma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
155 enum dma_data_direction dir)
156{
157 int i;
158
159 for (i = 0; i < nents; sg++, i++) {
160 sg->dma_address = sg_phys(sg);
161 dma_sync_single_for_device(dev, sg->dma_address, sg->length, dir);
162 }
163 return nents;
164}
165EXPORT_SYMBOL(dma_map_sg);
166
