diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /arch/i386/kernel/pci-dma.c |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'arch/i386/kernel/pci-dma.c')
-rw-r--r-- | arch/i386/kernel/pci-dma.c | 147 |
1 files changed, 147 insertions, 0 deletions
diff --git a/arch/i386/kernel/pci-dma.c b/arch/i386/kernel/pci-dma.c new file mode 100644 index 000000000000..4de2e03c7b45 --- /dev/null +++ b/arch/i386/kernel/pci-dma.c | |||
@@ -0,0 +1,147 @@ | |||
1 | /* | ||
2 | * Dynamic DMA mapping support. | ||
3 | * | ||
4 | * On i386 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 | |||
10 | #include <linux/types.h> | ||
11 | #include <linux/mm.h> | ||
12 | #include <linux/string.h> | ||
13 | #include <linux/pci.h> | ||
14 | #include <asm/io.h> | ||
15 | |||
16 | struct dma_coherent_mem { | ||
17 | void *virt_base; | ||
18 | u32 device_base; | ||
19 | int size; | ||
20 | int flags; | ||
21 | unsigned long *bitmap; | ||
22 | }; | ||
23 | |||
24 | void *dma_alloc_coherent(struct device *dev, size_t size, | ||
25 | dma_addr_t *dma_handle, unsigned int __nocast gfp) | ||
26 | { | ||
27 | void *ret; | ||
28 | struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL; | ||
29 | int order = get_order(size); | ||
30 | /* ignore region specifiers */ | ||
31 | gfp &= ~(__GFP_DMA | __GFP_HIGHMEM); | ||
32 | |||
33 | if (mem) { | ||
34 | int page = bitmap_find_free_region(mem->bitmap, mem->size, | ||
35 | order); | ||
36 | if (page >= 0) { | ||
37 | *dma_handle = mem->device_base + (page << PAGE_SHIFT); | ||
38 | ret = mem->virt_base + (page << PAGE_SHIFT); | ||
39 | memset(ret, 0, size); | ||
40 | return ret; | ||
41 | } | ||
42 | if (mem->flags & DMA_MEMORY_EXCLUSIVE) | ||
43 | return NULL; | ||
44 | } | ||
45 | |||
46 | if (dev == NULL || (dev->coherent_dma_mask < 0xffffffff)) | ||
47 | gfp |= GFP_DMA; | ||
48 | |||
49 | ret = (void *)__get_free_pages(gfp, order); | ||
50 | |||
51 | if (ret != NULL) { | ||
52 | memset(ret, 0, size); | ||
53 | *dma_handle = virt_to_phys(ret); | ||
54 | } | ||
55 | return ret; | ||
56 | } | ||
57 | |||
58 | void dma_free_coherent(struct device *dev, size_t size, | ||
59 | void *vaddr, dma_addr_t dma_handle) | ||
60 | { | ||
61 | struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL; | ||
62 | int order = get_order(size); | ||
63 | |||
64 | if (mem && vaddr >= mem->virt_base && vaddr < (mem->virt_base + (mem->size << PAGE_SHIFT))) { | ||
65 | int page = (vaddr - mem->virt_base) >> PAGE_SHIFT; | ||
66 | |||
67 | bitmap_release_region(mem->bitmap, page, order); | ||
68 | } else | ||
69 | free_pages((unsigned long)vaddr, order); | ||
70 | } | ||
71 | |||
72 | int dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr, | ||
73 | dma_addr_t device_addr, size_t size, int flags) | ||
74 | { | ||
75 | void __iomem *mem_base; | ||
76 | int pages = size >> PAGE_SHIFT; | ||
77 | int bitmap_size = (pages + 31)/32; | ||
78 | |||
79 | if ((flags & (DMA_MEMORY_MAP | DMA_MEMORY_IO)) == 0) | ||
80 | goto out; | ||
81 | if (!size) | ||
82 | goto out; | ||
83 | if (dev->dma_mem) | ||
84 | goto out; | ||
85 | |||
86 | /* FIXME: this routine just ignores DMA_MEMORY_INCLUDES_CHILDREN */ | ||
87 | |||
88 | mem_base = ioremap(bus_addr, size); | ||
89 | if (!mem_base) | ||
90 | goto out; | ||
91 | |||
92 | dev->dma_mem = kmalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL); | ||
93 | if (!dev->dma_mem) | ||
94 | goto out; | ||
95 | memset(dev->dma_mem, 0, sizeof(struct dma_coherent_mem)); | ||
96 | dev->dma_mem->bitmap = kmalloc(bitmap_size, GFP_KERNEL); | ||
97 | if (!dev->dma_mem->bitmap) | ||
98 | goto free1_out; | ||
99 | memset(dev->dma_mem->bitmap, 0, bitmap_size); | ||
100 | |||
101 | dev->dma_mem->virt_base = mem_base; | ||
102 | dev->dma_mem->device_base = device_addr; | ||
103 | dev->dma_mem->size = pages; | ||
104 | dev->dma_mem->flags = flags; | ||
105 | |||
106 | if (flags & DMA_MEMORY_MAP) | ||
107 | return DMA_MEMORY_MAP; | ||
108 | |||
109 | return DMA_MEMORY_IO; | ||
110 | |||
111 | free1_out: | ||
112 | kfree(dev->dma_mem->bitmap); | ||
113 | out: | ||
114 | return 0; | ||
115 | } | ||
116 | EXPORT_SYMBOL(dma_declare_coherent_memory); | ||
117 | |||
118 | void dma_release_declared_memory(struct device *dev) | ||
119 | { | ||
120 | struct dma_coherent_mem *mem = dev->dma_mem; | ||
121 | |||
122 | if(!mem) | ||
123 | return; | ||
124 | dev->dma_mem = NULL; | ||
125 | iounmap(mem->virt_base); | ||
126 | kfree(mem->bitmap); | ||
127 | kfree(mem); | ||
128 | } | ||
129 | EXPORT_SYMBOL(dma_release_declared_memory); | ||
130 | |||
131 | void *dma_mark_declared_memory_occupied(struct device *dev, | ||
132 | dma_addr_t device_addr, size_t size) | ||
133 | { | ||
134 | struct dma_coherent_mem *mem = dev->dma_mem; | ||
135 | int pages = (size + (device_addr & ~PAGE_MASK) + PAGE_SIZE - 1) >> PAGE_SHIFT; | ||
136 | int pos, err; | ||
137 | |||
138 | if (!mem) | ||
139 | return ERR_PTR(-EINVAL); | ||
140 | |||
141 | pos = (device_addr - mem->device_base) >> PAGE_SHIFT; | ||
142 | err = bitmap_allocate_region(mem->bitmap, pos, get_order(pages)); | ||
143 | if (err != 0) | ||
144 | return ERR_PTR(err); | ||
145 | return mem->virt_base + (pos << PAGE_SHIFT); | ||
146 | } | ||
147 | EXPORT_SYMBOL(dma_mark_declared_memory_occupied); | ||