Commit | Line | Data |
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1da177e4 LT |
1 | /* |
2 | * Support for DMA from PCI devices to main memory on | |
3 | * machines without an iommu or with directly addressable | |
4 | * RAM (typically a pmac with 2Gb of RAM or less) | |
5 | * | |
6 | * Copyright (C) 2003 Benjamin Herrenschmidt (benh@kernel.crashing.org) | |
7 | * | |
8 | * This program is free software; you can redistribute it and/or | |
9 | * modify it under the terms of the GNU General Public License | |
10 | * as published by the Free Software Foundation; either version | |
11 | * 2 of the License, or (at your option) any later version. | |
12 | */ | |
13 | ||
14 | #include <linux/kernel.h> | |
15 | #include <linux/pci.h> | |
16 | #include <linux/delay.h> | |
17 | #include <linux/string.h> | |
18 | #include <linux/init.h> | |
19 | #include <linux/bootmem.h> | |
20 | #include <linux/mm.h> | |
21 | #include <linux/dma-mapping.h> | |
22 | ||
23 | #include <asm/sections.h> | |
24 | #include <asm/io.h> | |
25 | #include <asm/prom.h> | |
26 | #include <asm/pci-bridge.h> | |
27 | #include <asm/machdep.h> | |
28 | #include <asm/pmac_feature.h> | |
29 | #include <asm/abs_addr.h> | |
d387899f | 30 | #include <asm/ppc-pci.h> |
1da177e4 LT |
31 | |
32 | static void *pci_direct_alloc_coherent(struct device *hwdev, size_t size, | |
dd0fc66f | 33 | dma_addr_t *dma_handle, gfp_t flag) |
1da177e4 LT |
34 | { |
35 | void *ret; | |
36 | ||
37 | ret = (void *)__get_free_pages(flag, get_order(size)); | |
38 | if (ret != NULL) { | |
39 | memset(ret, 0, size); | |
40 | *dma_handle = virt_to_abs(ret); | |
41 | } | |
42 | return ret; | |
43 | } | |
44 | ||
45 | static void pci_direct_free_coherent(struct device *hwdev, size_t size, | |
46 | void *vaddr, dma_addr_t dma_handle) | |
47 | { | |
48 | free_pages((unsigned long)vaddr, get_order(size)); | |
49 | } | |
50 | ||
51 | static dma_addr_t pci_direct_map_single(struct device *hwdev, void *ptr, | |
52 | size_t size, enum dma_data_direction direction) | |
53 | { | |
54 | return virt_to_abs(ptr); | |
55 | } | |
56 | ||
57 | static void pci_direct_unmap_single(struct device *hwdev, dma_addr_t dma_addr, | |
58 | size_t size, enum dma_data_direction direction) | |
59 | { | |
60 | } | |
61 | ||
62 | static int pci_direct_map_sg(struct device *hwdev, struct scatterlist *sg, | |
63 | int nents, enum dma_data_direction direction) | |
64 | { | |
65 | int i; | |
66 | ||
67 | for (i = 0; i < nents; i++, sg++) { | |
68 | sg->dma_address = page_to_phys(sg->page) + sg->offset; | |
69 | sg->dma_length = sg->length; | |
70 | } | |
71 | ||
72 | return nents; | |
73 | } | |
74 | ||
75 | static void pci_direct_unmap_sg(struct device *hwdev, struct scatterlist *sg, | |
76 | int nents, enum dma_data_direction direction) | |
77 | { | |
78 | } | |
79 | ||
80 | static int pci_direct_dma_supported(struct device *dev, u64 mask) | |
81 | { | |
82 | return mask < 0x100000000ull; | |
83 | } | |
84 | ||
df310656 AB |
85 | static struct dma_mapping_ops pci_direct_ops = { |
86 | .alloc_coherent = pci_direct_alloc_coherent, | |
87 | .free_coherent = pci_direct_free_coherent, | |
88 | .map_single = pci_direct_map_single, | |
89 | .unmap_single = pci_direct_unmap_single, | |
90 | .map_sg = pci_direct_map_sg, | |
91 | .unmap_sg = pci_direct_unmap_sg, | |
92 | .dma_supported = pci_direct_dma_supported, | |
93 | }; | |
94 | ||
1da177e4 LT |
95 | void __init pci_direct_iommu_init(void) |
96 | { | |
df310656 | 97 | pci_dma_ops = pci_direct_ops; |
1da177e4 | 98 | } |