summaryrefslogtreecommitdiffstats
path: root/kernel/tools/power/acpi/os_specific/service_layers/osunixmap.c
blob: 44ad4889d468cad4b576e39eaad4ef5ba3844b07 (plain)
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
/******************************************************************************
 *
 * Module Name: osunixmap - Unix OSL for file mappings
 *
 *****************************************************************************/

/*
 * Copyright (C) 2000 - 2015, Intel Corp.
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions, and the following disclaimer,
 *    without modification.
 * 2. Redistributions in binary form must reproduce at minimum a disclaimer
 *    substantially similar to the "NO WARRANTY" disclaimer below
 *    ("Disclaimer") and any redistribution must be conditioned upon
 *    including a substantially similar Disclaimer requirement for further
 *    binary redistribution.
 * 3. Neither the names of the above-listed copyright holders nor the names
 *    of any contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * NO WARRANTY
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTIBILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGES.
 */

#include "acpidump.h"
#include <unistd.h>
#include <sys/mman.h>
#ifdef _free_BSD
#include <sys/param.h>
#endif

#define _COMPONENT          ACPI_OS_SERVICES
ACPI_MODULE_NAME("osunixmap")

#ifndef O_BINARY
#define O_BINARY 0
#endif
#if defined(_dragon_fly) || defined(_free_BSD)
#define MMAP_FLAGS          MAP_SHARED
#else
#define MMAP_FLAGS          MAP_PRIVATE
#endif
#define SYSTEM_MEMORY       "/dev/mem"
/*******************************************************************************
 *
 * FUNCTION:    acpi_os_get_page_size
 *
 * PARAMETERS:  None
 *
 * RETURN:      Page size of the platform.
 *
 * DESCRIPTION: Obtain page size of the platform.
 *
 ******************************************************************************/
static acpi_size acpi_os_get_page_size(void)
{

#ifdef PAGE_SIZE
	return PAGE_SIZE;
#else
	return sysconf(_SC_PAGESIZE);
#endif
}

/******************************************************************************
 *
 * FUNCTION:    acpi_os_map_memory
 *
 * PARAMETERS:  where               - Physical address of memory to be mapped
 *              length              - How much memory to map
 *
 * RETURN:      Pointer to mapped memory. Null on error.
 *
 * DESCRIPTION: Map physical memory into local address space.
 *
 *****************************************************************************/

void *acpi_os_map_memory(acpi_physical_address where, acpi_size length)
{
	u8 *mapped_memory;
	acpi_physical_address offset;
	acpi_size page_size;
	int fd;

	fd = open(SYSTEM_MEMORY, O_RDONLY | O_BINARY);
	if (fd < 0) {
		fprintf(stderr, "Cannot open %s\n", SYSTEM_MEMORY);
		return (NULL);
	}

	/* Align the offset to use mmap */

	page_size = acpi_os_get_page_size();
	offset = where % page_size;

	/* Map the table header to get the length of the full table */

	mapped_memory = mmap(NULL, (length + offset), PROT_READ, MMAP_FLAGS,
			     fd, (where - offset));
	if (mapped_memory == MAP_FAILED) {
		fprintf(stderr, "Cannot map %s\n", SYSTEM_MEMORY);
		close(fd);
		return (NULL);
	}

	close(fd);
	return (ACPI_CAST8(mapped_memory + offset));
}

/******************************************************************************
 *
 * FUNCTION:    acpi_os_unmap_memory
 *
 * PARAMETERS:  where               - Logical address of memory to be unmapped
 *              length              - How much memory to unmap
 *
 * RETURN:      None.
 *
 * DESCRIPTION: Delete a previously created mapping. Where and Length must
 *              correspond to a previous mapping exactly.
 *
 *****************************************************************************/

void acpi_os_unmap_memory(void *where, acpi_size length)
{
	acpi_physical_address offset;
	acpi_size page_size;

	page_size = acpi_os_get_page_size();
	offset = ACPI_TO_INTEGER(where) % page_size;
	munmap((u8 *)where - offset, (length + offset));
}