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9663f2e6 KP |
1 | /* |
2 | * Copyright © 2008 Keith Packard <keithp@keithp.com> | |
3 | * | |
4 | * This file is free software; you can redistribute it and/or modify | |
5 | * it under the terms of version 2 of the GNU General Public License | |
6 | * as published by the Free Software Foundation. | |
7 | * | |
8 | * This program is distributed in the hope that it will be useful, | |
9 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
10 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
11 | * GNU General Public License for more details. | |
12 | * | |
13 | * You should have received a copy of the GNU General Public License | |
14 | * along with this program; if not, write to the Free Software Foundation, | |
15 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA. | |
16 | */ | |
17 | ||
18 | #ifndef _LINUX_IO_MAPPING_H | |
19 | #define _LINUX_IO_MAPPING_H | |
20 | ||
21 | #include <linux/types.h> | |
5a0e3ad6 | 22 | #include <linux/slab.h> |
187f1882 | 23 | #include <linux/bug.h> |
9663f2e6 KP |
24 | #include <asm/io.h> |
25 | #include <asm/page.h> | |
9663f2e6 KP |
26 | |
27 | /* | |
28 | * The io_mapping mechanism provides an abstraction for mapping | |
29 | * individual pages from an io device to the CPU in an efficient fashion. | |
30 | * | |
395cf969 | 31 | * See Documentation/io-mapping.txt |
9663f2e6 KP |
32 | */ |
33 | ||
e5beae16 KP |
34 | #ifdef CONFIG_HAVE_ATOMIC_IOMAP |
35 | ||
31ce4bfd DA |
36 | #include <asm/iomap.h> |
37 | ||
4ab0d47d VP |
38 | struct io_mapping { |
39 | resource_size_t base; | |
40 | unsigned long size; | |
41 | pgprot_t prot; | |
42 | }; | |
43 | ||
e5beae16 KP |
44 | /* |
45 | * For small address space machines, mapping large objects | |
46 | * into the kernel virtual space isn't practical. Where | |
47 | * available, use fixmap support to dynamically map pages | |
48 | * of the object at run time. | |
49 | */ | |
9663f2e6 | 50 | |
9663f2e6 | 51 | static inline struct io_mapping * |
4ab0d47d | 52 | io_mapping_create_wc(resource_size_t base, unsigned long size) |
9663f2e6 | 53 | { |
4ab0d47d | 54 | struct io_mapping *iomap; |
9e36fda0 | 55 | pgprot_t prot; |
4ab0d47d VP |
56 | |
57 | iomap = kmalloc(sizeof(*iomap), GFP_KERNEL); | |
58 | if (!iomap) | |
9e36fda0 VP |
59 | goto out_err; |
60 | ||
61 | if (iomap_create_wc(base, size, &prot)) | |
62 | goto out_free; | |
4ab0d47d VP |
63 | |
64 | iomap->base = base; | |
65 | iomap->size = size; | |
9e36fda0 | 66 | iomap->prot = prot; |
4ab0d47d | 67 | return iomap; |
9e36fda0 VP |
68 | |
69 | out_free: | |
70 | kfree(iomap); | |
71 | out_err: | |
72 | return NULL; | |
9663f2e6 KP |
73 | } |
74 | ||
75 | static inline void | |
76 | io_mapping_free(struct io_mapping *mapping) | |
77 | { | |
9e36fda0 | 78 | iomap_free(mapping->base, mapping->size); |
4ab0d47d | 79 | kfree(mapping); |
9663f2e6 KP |
80 | } |
81 | ||
82 | /* Atomic map/unmap */ | |
29bc17ec | 83 | static inline void __iomem * |
fca3ec01 | 84 | io_mapping_map_atomic_wc(struct io_mapping *mapping, |
3e4d3af5 | 85 | unsigned long offset) |
9663f2e6 | 86 | { |
4ab0d47d VP |
87 | resource_size_t phys_addr; |
88 | unsigned long pfn; | |
89 | ||
90 | BUG_ON(offset >= mapping->size); | |
91 | phys_addr = mapping->base + offset; | |
92 | pfn = (unsigned long) (phys_addr >> PAGE_SHIFT); | |
3e4d3af5 | 93 | return iomap_atomic_prot_pfn(pfn, mapping->prot); |
9663f2e6 KP |
94 | } |
95 | ||
96 | static inline void | |
3e4d3af5 | 97 | io_mapping_unmap_atomic(void __iomem *vaddr) |
9663f2e6 | 98 | { |
3e4d3af5 | 99 | iounmap_atomic(vaddr); |
9663f2e6 KP |
100 | } |
101 | ||
29bc17ec | 102 | static inline void __iomem * |
9663f2e6 KP |
103 | io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset) |
104 | { | |
5ce04e3d PV |
105 | resource_size_t phys_addr; |
106 | ||
4ab0d47d | 107 | BUG_ON(offset >= mapping->size); |
5ce04e3d PV |
108 | phys_addr = mapping->base + offset; |
109 | ||
4ab0d47d | 110 | return ioremap_wc(phys_addr, PAGE_SIZE); |
9663f2e6 KP |
111 | } |
112 | ||
113 | static inline void | |
29bc17ec | 114 | io_mapping_unmap(void __iomem *vaddr) |
9663f2e6 | 115 | { |
e5beae16 | 116 | iounmap(vaddr); |
9663f2e6 KP |
117 | } |
118 | ||
e5beae16 | 119 | #else |
9663f2e6 | 120 | |
24dd85ff DV |
121 | #include <linux/uaccess.h> |
122 | ||
4ab0d47d VP |
123 | /* this struct isn't actually defined anywhere */ |
124 | struct io_mapping; | |
125 | ||
e5beae16 | 126 | /* Create the io_mapping object*/ |
9663f2e6 | 127 | static inline struct io_mapping * |
4ab0d47d | 128 | io_mapping_create_wc(resource_size_t base, unsigned long size) |
9663f2e6 | 129 | { |
29bc17ec | 130 | return (struct io_mapping __force *) ioremap_wc(base, size); |
9663f2e6 KP |
131 | } |
132 | ||
133 | static inline void | |
134 | io_mapping_free(struct io_mapping *mapping) | |
135 | { | |
29bc17ec | 136 | iounmap((void __force __iomem *) mapping); |
9663f2e6 KP |
137 | } |
138 | ||
139 | /* Atomic map/unmap */ | |
29bc17ec | 140 | static inline void __iomem * |
fca3ec01 | 141 | io_mapping_map_atomic_wc(struct io_mapping *mapping, |
3e4d3af5 | 142 | unsigned long offset) |
9663f2e6 | 143 | { |
24dd85ff | 144 | pagefault_disable(); |
29bc17ec | 145 | return ((char __force __iomem *) mapping) + offset; |
9663f2e6 KP |
146 | } |
147 | ||
148 | static inline void | |
3e4d3af5 | 149 | io_mapping_unmap_atomic(void __iomem *vaddr) |
9663f2e6 | 150 | { |
24dd85ff | 151 | pagefault_enable(); |
9663f2e6 KP |
152 | } |
153 | ||
e5beae16 | 154 | /* Non-atomic map/unmap */ |
29bc17ec | 155 | static inline void __iomem * |
9663f2e6 KP |
156 | io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset) |
157 | { | |
29bc17ec | 158 | return ((char __force __iomem *) mapping) + offset; |
9663f2e6 KP |
159 | } |
160 | ||
161 | static inline void | |
29bc17ec | 162 | io_mapping_unmap(void __iomem *vaddr) |
9663f2e6 | 163 | { |
9663f2e6 | 164 | } |
e5beae16 KP |
165 | |
166 | #endif /* HAVE_ATOMIC_IOMAP */ | |
9663f2e6 KP |
167 | |
168 | #endif /* _LINUX_IO_MAPPING_H */ |