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
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
|
/* Copyright (C) 1999-2016 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by David Mosberger-Tang <davidm@hpl.hp.com>.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
/* I/O access is restricted to ISA port space (ports 0..65535).
Modern devices hopefully are sane enough not to put any performance
critical registers in i/o space.
On the first call to ioperm() or iopl(), the entire (E)ISA port
space is mapped into the virtual address space at address io.base.
mprotect() calls are then used to enable/disable access to ports.
Per 4KB page, there are 4 I/O ports. */
#include <errno.h>
#include <fcntl.h>
#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/mman.h>
#define MAX_PORT 0x10000
/*
* Memory fence w/accept. This should never be used in code that is
* not IA-64 specific.
*/
#define __ia64_mf_a() __asm__ __volatile__ ("mf.a" ::: "memory")
static struct
{
unsigned long int base;
unsigned long int page_mask;
}
io;
__inline__ unsigned long int
io_offset (unsigned long int port)
{
return ((port >> 2) << 12) | (port & 0xfff);
}
int
_ioperm (unsigned long int from, unsigned long int num, int turn_on)
{
unsigned long int base;
/* this test isn't as silly as it may look like; consider overflows! */
if (from >= MAX_PORT || from + num > MAX_PORT)
{
__set_errno (EINVAL);
return -1;
}
if (turn_on)
{
if (!io.base)
{
unsigned long phys_io_base, len;
int fd;
io.page_mask = ~(__getpagesize() - 1);
/* get I/O base physical address from ar.k0 as per PRM: */
__asm__ ("mov %0=ar.k0" : "=r"(phys_io_base));
/* The O_SYNC flag tells the /dev/mem driver to map the
memory uncached: */
fd = __open ("/dev/mem", O_RDWR | O_SYNC);
if (fd < 0)
return -1;
len = io_offset (MAX_PORT);
/* see comment below */
base = (unsigned long int) __mmap (0, len, PROT_READ | PROT_WRITE, MAP_SHARED,
fd, phys_io_base);
__close (fd);
if ((long) base == -1)
return -1;
io.base = base;
}
}
else
{
if (!io.base)
return 0; /* never was turned on... */
}
/* We can't do mprotect because that would cause us to lose the
uncached flag that the /dev/mem driver turned on. A MAP_UNCACHED
flag seems so much cleaner...
See the history of this file for a version that tried mprotect. */
return 0;
}
int
_iopl (unsigned int level)
{
if (level > 3)
{
__set_errno (EINVAL);
return -1;
}
if (level)
{
int retval = _ioperm (0, MAX_PORT, 1);
/* Match the documented error returns of the x86 version. */
if (retval < 0 && errno == EACCES)
__set_errno (EPERM);
return retval;
}
return 0;
}
unsigned int
_inb (unsigned long int port)
{
volatile unsigned char *addr = (void *) io.base + io_offset (port);
unsigned char ret;
ret = *addr;
__ia64_mf_a();
return ret;
}
unsigned int
_inw (unsigned long int port)
{
volatile unsigned short *addr = (void *) io.base + io_offset (port);
unsigned short ret;
ret = *addr;
__ia64_mf_a();
return ret;
}
unsigned int
_inl (unsigned long int port)
{
volatile unsigned int *addr = (void *) io.base + io_offset (port);
unsigned int ret;
ret = *addr;
__ia64_mf_a();
return ret;
}
void
_outb (unsigned char val, unsigned long int port)
{
volatile unsigned char *addr = (void *) io.base + io_offset (port);
*addr = val;
__ia64_mf_a();
}
void
_outw (unsigned short val, unsigned long int port)
{
volatile unsigned short *addr = (void *) io.base + io_offset (port);
*addr = val;
__ia64_mf_a();
}
void
_outl (unsigned int val, unsigned long int port)
{
volatile unsigned int *addr = (void *) io.base + io_offset (port);
*addr = val;
__ia64_mf_a();
}
weak_alias (_ioperm, ioperm);
weak_alias (_iopl, iopl);
weak_alias (_inb, inb);
weak_alias (_inw, inw);
weak_alias (_inl, inl);
weak_alias (_outb, outb);
weak_alias (_outw, outw);
weak_alias (_outl, outl);
|
