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path: root/arch/cris/arch-v32/drivers/pci/dma.c
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Diffstat (limited to 'arch/cris/arch-v32/drivers/pci/dma.c')
-rw-r--r--arch/cris/arch-v32/drivers/pci/dma.c149
1 files changed, 149 insertions, 0 deletions
diff --git a/arch/cris/arch-v32/drivers/pci/dma.c b/arch/cris/arch-v32/drivers/pci/dma.c
new file mode 100644
index 000000000000..10329306d23c
--- /dev/null
+++ b/arch/cris/arch-v32/drivers/pci/dma.c
@@ -0,0 +1,149 @@
1/*
2 * Dynamic DMA mapping support.
3 *
4 * On cris 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 * Borrowed from i386.
10 */
11
12#include <linux/types.h>
13#include <linux/mm.h>
14#include <linux/string.h>
15#include <linux/pci.h>
16#include <asm/io.h>
17
18struct dma_coherent_mem {
19 void *virt_base;
20 u32 device_base;
21 int size;
22 int flags;
23 unsigned long *bitmap;
24};
25
26void *dma_alloc_coherent(struct device *dev, size_t size,
27 dma_addr_t *dma_handle, unsigned int __nocast gfp)
28{
29 void *ret;
30 struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL;
31 int order = get_order(size);
32 /* ignore region specifiers */
33 gfp &= ~(__GFP_DMA | __GFP_HIGHMEM);
34
35 if (mem) {
36 int page = bitmap_find_free_region(mem->bitmap, mem->size,
37 order);
38 if (page >= 0) {
39 *dma_handle = mem->device_base + (page << PAGE_SHIFT);
40 ret = mem->virt_base + (page << PAGE_SHIFT);
41 memset(ret, 0, size);
42 return ret;
43 }
44 if (mem->flags & DMA_MEMORY_EXCLUSIVE)
45 return NULL;
46 }
47
48 if (dev == NULL || (dev->coherent_dma_mask < 0xffffffff))
49 gfp |= GFP_DMA;
50
51 ret = (void *)__get_free_pages(gfp, order);
52
53 if (ret != NULL) {
54 memset(ret, 0, size);
55 *dma_handle = virt_to_phys(ret);
56 }
57 return ret;
58}
59
60void dma_free_coherent(struct device *dev, size_t size,
61 void *vaddr, dma_addr_t dma_handle)
62{
63 struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL;
64 int order = get_order(size);
65
66 if (mem && vaddr >= mem->virt_base && vaddr < (mem->virt_base + (mem->size << PAGE_SHIFT))) {
67 int page = (vaddr - mem->virt_base) >> PAGE_SHIFT;
68
69 bitmap_release_region(mem->bitmap, page, order);
70 } else
71 free_pages((unsigned long)vaddr, order);
72}
73
74int dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr,
75 dma_addr_t device_addr, size_t size, int flags)
76{
77 void __iomem *mem_base;
78 int pages = size >> PAGE_SHIFT;
79 int bitmap_size = (pages + 31)/32;
80
81 if ((flags & (DMA_MEMORY_MAP | DMA_MEMORY_IO)) == 0)
82 goto out;
83 if (!size)
84 goto out;
85 if (dev->dma_mem)
86 goto out;
87
88 /* FIXME: this routine just ignores DMA_MEMORY_INCLUDES_CHILDREN */
89
90 mem_base = ioremap(bus_addr, size);
91 if (!mem_base)
92 goto out;
93
94 dev->dma_mem = kmalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL);
95 if (!dev->dma_mem)
96 goto out;
97 memset(dev->dma_mem, 0, sizeof(struct dma_coherent_mem));
98 dev->dma_mem->bitmap = kmalloc(bitmap_size, GFP_KERNEL);
99 if (!dev->dma_mem->bitmap)
100 goto free1_out;
101 memset(dev->dma_mem->bitmap, 0, bitmap_size);
102
103 dev->dma_mem->virt_base = mem_base;
104 dev->dma_mem->device_base = device_addr;
105 dev->dma_mem->size = pages;
106 dev->dma_mem->flags = flags;
107
108 if (flags & DMA_MEMORY_MAP)
109 return DMA_MEMORY_MAP;
110
111 return DMA_MEMORY_IO;
112
113 free1_out:
114 kfree(dev->dma_mem->bitmap);
115 out:
116 return 0;
117}
118EXPORT_SYMBOL(dma_declare_coherent_memory);
119
120void dma_release_declared_memory(struct device *dev)
121{
122 struct dma_coherent_mem *mem = dev->dma_mem;
123
124 if(!mem)
125 return;
126 dev->dma_mem = NULL;
127 iounmap(mem->virt_base);
128 kfree(mem->bitmap);
129 kfree(mem);
130}
131EXPORT_SYMBOL(dma_release_declared_memory);
132
133void *dma_mark_declared_memory_occupied(struct device *dev,
134 dma_addr_t device_addr, size_t size)
135{
136 struct dma_coherent_mem *mem = dev->dma_mem;
137 int pages = (size + (device_addr & ~PAGE_MASK) + PAGE_SIZE - 1) >> PAGE_SHIFT;
138 int pos, err;
139
140 if (!mem)
141 return ERR_PTR(-EINVAL);
142
143 pos = (device_addr - mem->device_base) >> PAGE_SHIFT;
144 err = bitmap_allocate_region(mem->bitmap, pos, get_order(pages));
145 if (err != 0)
146 return ERR_PTR(err);
147 return mem->virt_base + (pos << PAGE_SHIFT);
148}
149EXPORT_SYMBOL(dma_mark_declared_memory_occupied);