Commit | Line | Data |
---|---|---|
1da177e4 | 1 | /* |
12d04eef | 2 | * Copyright (C) 2006 Benjamin Herrenschmidt, IBM Corporation |
1da177e4 | 3 | * |
12d04eef | 4 | * Provide default implementations of the DMA mapping callbacks for |
8dd0e952 | 5 | * directly mapped busses. |
1da177e4 LT |
6 | */ |
7 | ||
8 | #include <linux/device.h> | |
9 | #include <linux/dma-mapping.h> | |
1da177e4 | 10 | #include <asm/bug.h> |
12d04eef | 11 | #include <asm/abs_addr.h> |
1da177e4 | 12 | |
12d04eef BH |
13 | /* |
14 | * Generic direct DMA implementation | |
92b20c40 | 15 | * |
31d1b493 ME |
16 | * This implementation supports a per-device offset that can be applied if |
17 | * the address at which memory is visible to devices is not 0. Platform code | |
18 | * can set archdata.dma_data to an unsigned long holding the offset. By | |
4fc665b8 | 19 | * default the offset is PCI_DRAM_OFFSET. |
12d04eef | 20 | */ |
5d33eebe | 21 | |
35e4a6e2 ME |
22 | static unsigned long get_dma_direct_offset(struct device *dev) |
23 | { | |
4fc665b8 BB |
24 | if (dev) |
25 | return (unsigned long)dev->archdata.dma_data; | |
26 | ||
27 | return PCI_DRAM_OFFSET; | |
35e4a6e2 ME |
28 | } |
29 | ||
4fc665b8 BB |
30 | void *dma_direct_alloc_coherent(struct device *dev, size_t size, |
31 | dma_addr_t *dma_handle, gfp_t flag) | |
12d04eef | 32 | { |
8aa26590 | 33 | void *ret; |
4fc665b8 | 34 | #ifdef CONFIG_NOT_COHERENT_CACHE |
8aa26590 BH |
35 | ret = __dma_alloc_coherent(size, dma_handle, flag); |
36 | if (ret == NULL) | |
37 | return NULL; | |
38 | *dma_handle += get_dma_direct_offset(dev); | |
39 | return ret; | |
4fc665b8 | 40 | #else |
c80d9133 | 41 | struct page *page; |
8fae0353 | 42 | int node = dev_to_node(dev); |
12d04eef | 43 | |
4fc665b8 BB |
44 | /* ignore region specifiers */ |
45 | flag &= ~(__GFP_HIGHMEM); | |
46 | ||
c80d9133 BH |
47 | page = alloc_pages_node(node, flag, get_order(size)); |
48 | if (page == NULL) | |
49 | return NULL; | |
50 | ret = page_address(page); | |
51 | memset(ret, 0, size); | |
35e4a6e2 | 52 | *dma_handle = virt_to_abs(ret) + get_dma_direct_offset(dev); |
c80d9133 | 53 | |
12d04eef | 54 | return ret; |
4fc665b8 | 55 | #endif |
1da177e4 | 56 | } |
1da177e4 | 57 | |
4fc665b8 BB |
58 | void dma_direct_free_coherent(struct device *dev, size_t size, |
59 | void *vaddr, dma_addr_t dma_handle) | |
1da177e4 | 60 | { |
4fc665b8 BB |
61 | #ifdef CONFIG_NOT_COHERENT_CACHE |
62 | __dma_free_coherent(size, vaddr); | |
63 | #else | |
12d04eef | 64 | free_pages((unsigned long)vaddr, get_order(size)); |
4fc665b8 | 65 | #endif |
1da177e4 | 66 | } |
1da177e4 | 67 | |
78bdc310 | 68 | static int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, |
3affedc4 MN |
69 | int nents, enum dma_data_direction direction, |
70 | struct dma_attrs *attrs) | |
1da177e4 | 71 | { |
78bdc310 | 72 | struct scatterlist *sg; |
12d04eef | 73 | int i; |
1da177e4 | 74 | |
78bdc310 | 75 | for_each_sg(sgl, sg, nents, i) { |
35e4a6e2 | 76 | sg->dma_address = sg_phys(sg) + get_dma_direct_offset(dev); |
12d04eef | 77 | sg->dma_length = sg->length; |
2434bbb3 | 78 | __dma_sync_page(sg_page(sg), sg->offset, sg->length, direction); |
12d04eef | 79 | } |
5d33eebe | 80 | |
12d04eef | 81 | return nents; |
1da177e4 | 82 | } |
1da177e4 | 83 | |
12d04eef | 84 | static void dma_direct_unmap_sg(struct device *dev, struct scatterlist *sg, |
3affedc4 MN |
85 | int nents, enum dma_data_direction direction, |
86 | struct dma_attrs *attrs) | |
1da177e4 | 87 | { |
12d04eef | 88 | } |
5d33eebe | 89 | |
12d04eef BH |
90 | static int dma_direct_dma_supported(struct device *dev, u64 mask) |
91 | { | |
4fc665b8 | 92 | #ifdef CONFIG_PPC64 |
12d04eef BH |
93 | /* Could be improved to check for memory though it better be |
94 | * done via some global so platforms can set the limit in case | |
95 | * they have limited DMA windows | |
96 | */ | |
284901a9 | 97 | return mask >= DMA_BIT_MASK(32); |
4fc665b8 BB |
98 | #else |
99 | return 1; | |
100 | #endif | |
101 | } | |
102 | ||
103 | static inline dma_addr_t dma_direct_map_page(struct device *dev, | |
104 | struct page *page, | |
105 | unsigned long offset, | |
106 | size_t size, | |
107 | enum dma_data_direction dir, | |
108 | struct dma_attrs *attrs) | |
109 | { | |
110 | BUG_ON(dir == DMA_NONE); | |
111 | __dma_sync_page(page, offset, size, dir); | |
112 | return page_to_phys(page) + offset + get_dma_direct_offset(dev); | |
113 | } | |
114 | ||
115 | static inline void dma_direct_unmap_page(struct device *dev, | |
116 | dma_addr_t dma_address, | |
117 | size_t size, | |
118 | enum dma_data_direction direction, | |
119 | struct dma_attrs *attrs) | |
120 | { | |
1da177e4 | 121 | } |
12d04eef | 122 | |
15e09c0e BB |
123 | #ifdef CONFIG_NOT_COHERENT_CACHE |
124 | static inline void dma_direct_sync_sg(struct device *dev, | |
125 | struct scatterlist *sgl, int nents, | |
126 | enum dma_data_direction direction) | |
127 | { | |
128 | struct scatterlist *sg; | |
129 | int i; | |
130 | ||
131 | for_each_sg(sgl, sg, nents, i) | |
132 | __dma_sync_page(sg_page(sg), sg->offset, sg->length, direction); | |
133 | } | |
134 | ||
135 | static inline void dma_direct_sync_single_range(struct device *dev, | |
136 | dma_addr_t dma_handle, unsigned long offset, size_t size, | |
137 | enum dma_data_direction direction) | |
138 | { | |
139 | __dma_sync(bus_to_virt(dma_handle+offset), size, direction); | |
140 | } | |
141 | #endif | |
142 | ||
12d04eef BH |
143 | struct dma_mapping_ops dma_direct_ops = { |
144 | .alloc_coherent = dma_direct_alloc_coherent, | |
145 | .free_coherent = dma_direct_free_coherent, | |
12d04eef BH |
146 | .map_sg = dma_direct_map_sg, |
147 | .unmap_sg = dma_direct_unmap_sg, | |
148 | .dma_supported = dma_direct_dma_supported, | |
4fc665b8 BB |
149 | .map_page = dma_direct_map_page, |
150 | .unmap_page = dma_direct_unmap_page, | |
15e09c0e BB |
151 | #ifdef CONFIG_NOT_COHERENT_CACHE |
152 | .sync_single_range_for_cpu = dma_direct_sync_single_range, | |
153 | .sync_single_range_for_device = dma_direct_sync_single_range, | |
154 | .sync_sg_for_cpu = dma_direct_sync_sg, | |
155 | .sync_sg_for_device = dma_direct_sync_sg, | |
156 | #endif | |
12d04eef BH |
157 | }; |
158 | EXPORT_SYMBOL(dma_direct_ops); |