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12#include <linux/types.h>
13#include <linux/slab.h>
14#include <linux/export.h>
15#include <linux/dma-mapping.h>
16#include <linux/list.h>
17#include <linux/pci.h>
18#include <asm/io.h>
19
20#if 1
21#define DMA_SRAM_START dma_coherent_mem_start
22#define DMA_SRAM_END dma_coherent_mem_end
23#else
24#define DMA_SRAM_START 0xe8900000
25#define DMA_SRAM_END 0xe8a00000
26#endif
27
28struct dma_alloc_record {
29 struct list_head list;
30 unsigned long ofs;
31 unsigned long len;
32};
33
34static DEFINE_SPINLOCK(dma_alloc_lock);
35static LIST_HEAD(dma_alloc_list);
36
37static void *frv_dma_alloc(struct device *hwdev, size_t size, dma_addr_t *dma_handle,
38 gfp_t gfp, struct dma_attrs *attrs)
39{
40 struct dma_alloc_record *new;
41 struct list_head *this = &dma_alloc_list;
42 unsigned long flags;
43 unsigned long start = DMA_SRAM_START;
44 unsigned long end;
45
46 if (!DMA_SRAM_START) {
47 printk("%s called without any DMA area reserved!\n", __func__);
48 return NULL;
49 }
50
51 new = kmalloc(sizeof (*new), GFP_ATOMIC);
52 if (!new)
53 return NULL;
54
55
56 new->len = (size + 31) & ~31;
57
58 spin_lock_irqsave(&dma_alloc_lock, flags);
59
60 list_for_each (this, &dma_alloc_list) {
61 struct dma_alloc_record *this_r = list_entry(this, struct dma_alloc_record, list);
62 end = this_r->ofs;
63
64 if (end - start >= size)
65 goto gotone;
66
67 start = this_r->ofs + this_r->len;
68 }
69
70 end = DMA_SRAM_END;
71 this = &dma_alloc_list;
72
73 if (end - start >= size) {
74 gotone:
75 new->ofs = start;
76 list_add_tail(&new->list, this);
77 spin_unlock_irqrestore(&dma_alloc_lock, flags);
78
79 *dma_handle = start;
80 return (void *)start;
81 }
82
83 kfree(new);
84 spin_unlock_irqrestore(&dma_alloc_lock, flags);
85 return NULL;
86}
87
88static void frv_dma_free(struct device *hwdev, size_t size, void *vaddr,
89 dma_addr_t dma_handle, struct dma_attrs *attrs)
90{
91 struct dma_alloc_record *rec;
92 unsigned long flags;
93
94 spin_lock_irqsave(&dma_alloc_lock, flags);
95
96 list_for_each_entry(rec, &dma_alloc_list, list) {
97 if (rec->ofs == dma_handle) {
98 list_del(&rec->list);
99 kfree(rec);
100 spin_unlock_irqrestore(&dma_alloc_lock, flags);
101 return;
102 }
103 }
104 spin_unlock_irqrestore(&dma_alloc_lock, flags);
105 BUG();
106}
107
108static int frv_dma_map_sg(struct device *dev, struct scatterlist *sglist,
109 int nents, enum dma_data_direction direction,
110 struct dma_attrs *attrs)
111{
112 int i;
113 struct scatterlist *sg;
114
115 for_each_sg(sglist, sg, nents, i) {
116 frv_cache_wback_inv(sg_dma_address(sg),
117 sg_dma_address(sg) + sg_dma_len(sg));
118 }
119
120 BUG_ON(direction == DMA_NONE);
121
122 return nents;
123}
124
125static dma_addr_t frv_dma_map_page(struct device *dev, struct page *page,
126 unsigned long offset, size_t size,
127 enum dma_data_direction direction, struct dma_attrs *attrs)
128{
129 BUG_ON(direction == DMA_NONE);
130 flush_dcache_page(page);
131 return (dma_addr_t) page_to_phys(page) + offset;
132}
133
134static void frv_dma_sync_single_for_device(struct device *dev,
135 dma_addr_t dma_handle, size_t size,
136 enum dma_data_direction direction)
137{
138 flush_write_buffers();
139}
140
141static void frv_dma_sync_sg_for_device(struct device *dev,
142 struct scatterlist *sg, int nelems,
143 enum dma_data_direction direction)
144{
145 flush_write_buffers();
146}
147
148
149static int frv_dma_supported(struct device *dev, u64 mask)
150{
151
152
153
154
155
156 if (mask < 0x00ffffff)
157 return 0;
158 return 1;
159}
160
161struct dma_map_ops frv_dma_ops = {
162 .alloc = frv_dma_alloc,
163 .free = frv_dma_free,
164 .map_page = frv_dma_map_page,
165 .map_sg = frv_dma_map_sg,
166 .sync_single_for_device = frv_dma_sync_single_for_device,
167 .sync_sg_for_device = frv_dma_sync_sg_for_device,
168 .dma_supported = frv_dma_supported,
169};
170EXPORT_SYMBOL(frv_dma_ops);
171