1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
|
/*
* Copyright © 2008 Keith Packard <keithp@keithp.com>
*
* This file is free software; you can redistribute it and/or modify
* it under the terms of version 2 of the GNU General Public License
* as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#ifndef _LINUX_IO_MAPPING_H
#define _LINUX_IO_MAPPING_H
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/bug.h>
#include <asm/io.h>
#include <asm/page.h>
/*
* The io_mapping mechanism provides an abstraction for mapping
* individual pages from an io device to the CPU in an efficient fashion.
*
* See Documentation/io-mapping.txt
*/
#ifdef CONFIG_HAVE_ATOMIC_IOMAP
#include <asm/iomap.h>
struct io_mapping {
resource_size_t base;
unsigned long size;
pgprot_t prot;
};
/*
* For small address space machines, mapping large objects
* into the kernel virtual space isn't practical. Where
* available, use fixmap support to dynamically map pages
* of the object at run time.
*/
static inline struct io_mapping *
io_mapping_create_wc(resource_size_t base, unsigned long size)
{
struct io_mapping *iomap;
pgprot_t prot;
iomap = kmalloc(sizeof(*iomap), GFP_KERNEL);
if (!iomap)
goto out_err;
if (iomap_create_wc(base, size, &prot))
goto out_free;
iomap->base = base;
iomap->size = size;
iomap->prot = prot;
return iomap;
out_free:
kfree(iomap);
out_err:
return NULL;
}
static inline void
io_mapping_free(struct io_mapping *mapping)
{
iomap_free(mapping->base, mapping->size);
kfree(mapping);
}
/* Atomic map/unmap */
static inline void __iomem *
io_mapping_map_atomic_wc(struct io_mapping *mapping,
unsigned long offset)
{
resource_size_t phys_addr;
unsigned long pfn;
BUG_ON(offset >= mapping->size);
phys_addr = mapping->base + offset;
pfn = (unsigned long) (phys_addr >> PAGE_SHIFT);
return iomap_atomic_prot_pfn(pfn, mapping->prot);
}
static inline void
io_mapping_unmap_atomic(void __iomem *vaddr)
{
iounmap_atomic(vaddr);
}
static inline void __iomem *
io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset)
{
resource_size_t phys_addr;
BUG_ON(offset >= mapping->size);
phys_addr = mapping->base + offset;
return ioremap_wc(phys_addr, PAGE_SIZE);
}
static inline void
io_mapping_unmap(void __iomem *vaddr)
{
iounmap(vaddr);
}
#else
#include <linux/uaccess.h>
/* this struct isn't actually defined anywhere */
struct io_mapping;
/* Create the io_mapping object*/
static inline struct io_mapping *
io_mapping_create_wc(resource_size_t base, unsigned long size)
{
return (struct io_mapping __force *) ioremap_wc(base, size);
}
static inline void
io_mapping_free(struct io_mapping *mapping)
{
iounmap((void __force __iomem *) mapping);
}
/* Atomic map/unmap */
static inline void __iomem *
io_mapping_map_atomic_wc(struct io_mapping *mapping,
unsigned long offset)
{
preempt_disable();
pagefault_disable();
return ((char __force __iomem *) mapping) + offset;
}
static inline void
io_mapping_unmap_atomic(void __iomem *vaddr)
{
pagefault_enable();
preempt_enable();
}
/* Non-atomic map/unmap */
static inline void __iomem *
io_mapping_map_wc(struct io_mapping *mapping, unsigned long offset)
{
return ((char __force __iomem *) mapping) + offset;
}
static inline void
io_mapping_unmap(void __iomem *vaddr)
{
}
#endif /* HAVE_ATOMIC_IOMAP */
#endif /* _LINUX_IO_MAPPING_H */
|
