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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
51533b61 MS |
2 | /* |
3 | * Dynamic DMA mapping support. | |
4 | * | |
5 | * On cris there is no hardware dynamic DMA address translation, | |
6 | * so consistent alloc/free are merely page allocation/freeing. | |
7 | * The rest of the dynamic DMA mapping interface is implemented | |
8 | * in asm/pci.h. | |
9 | * | |
10 | * Borrowed from i386. | |
11 | */ | |
12 | ||
13 | #include <linux/types.h> | |
14 | #include <linux/mm.h> | |
15 | #include <linux/string.h> | |
16 | #include <linux/pci.h> | |
5a0e3ad6 | 17 | #include <linux/gfp.h> |
51533b61 MS |
18 | #include <asm/io.h> |
19 | ||
e20dd889 | 20 | static void *v32_dma_alloc(struct device *dev, size_t size, |
00085f1e | 21 | dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs) |
51533b61 MS |
22 | { |
23 | void *ret; | |
e20dd889 | 24 | |
51533b61 MS |
25 | if (dev == NULL || (dev->coherent_dma_mask < 0xffffffff)) |
26 | gfp |= GFP_DMA; | |
27 | ||
e20dd889 | 28 | ret = (void *)__get_free_pages(gfp, get_order(size)); |
51533b61 MS |
29 | |
30 | if (ret != NULL) { | |
31 | memset(ret, 0, size); | |
32 | *dma_handle = virt_to_phys(ret); | |
33 | } | |
34 | return ret; | |
35 | } | |
36 | ||
e20dd889 | 37 | static void v32_dma_free(struct device *dev, size_t size, void *vaddr, |
00085f1e | 38 | dma_addr_t dma_handle, unsigned long attrs) |
e20dd889 CH |
39 | { |
40 | free_pages((unsigned long)vaddr, get_order(size)); | |
41 | } | |
42 | ||
43 | static inline dma_addr_t v32_dma_map_page(struct device *dev, | |
44 | struct page *page, unsigned long offset, size_t size, | |
00085f1e | 45 | enum dma_data_direction direction, unsigned long attrs) |
51533b61 | 46 | { |
e20dd889 CH |
47 | return page_to_phys(page) + offset; |
48 | } | |
51533b61 | 49 | |
e20dd889 CH |
50 | static inline int v32_dma_map_sg(struct device *dev, struct scatterlist *sg, |
51 | int nents, enum dma_data_direction direction, | |
00085f1e | 52 | unsigned long attrs) |
e20dd889 CH |
53 | { |
54 | printk("Map sg\n"); | |
55 | return nents; | |
56 | } | |
57 | ||
58 | static inline int v32_dma_supported(struct device *dev, u64 mask) | |
59 | { | |
60 | /* | |
61 | * we fall back to GFP_DMA when the mask isn't all 1s, | |
62 | * so we can't guarantee allocations that must be | |
63 | * within a tighter range than GFP_DMA.. | |
64 | */ | |
65 | if (mask < 0x00ffffff) | |
66 | return 0; | |
67 | return 1; | |
51533b61 MS |
68 | } |
69 | ||
5299709d | 70 | const struct dma_map_ops v32_dma_ops = { |
e20dd889 CH |
71 | .alloc = v32_dma_alloc, |
72 | .free = v32_dma_free, | |
73 | .map_page = v32_dma_map_page, | |
74 | .map_sg = v32_dma_map_sg, | |
75 | .dma_supported = v32_dma_supported, | |
76 | }; | |
77 | EXPORT_SYMBOL(v32_dma_ops); |