xref: /freebsd/sys/dev/smbios/smbios.h (revision 105fd928b0b5b35ab529e5f6914788dc49582901)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 1997 Michael Smith
5  * Copyright (c) 1998 Jonathan Lemon
6  * All rights reserved.
7  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  *
29  * $FreeBSD$
30  */
31 
32 #ifndef _SMBIOS_H_
33 #define _SMBIOS_H_
34 
35 /*
36  * System Management BIOS
37  */
38 #define	SMBIOS_START	0xf0000
39 #define	SMBIOS_STEP	0x10
40 #define	SMBIOS_OFF	0
41 #define	SMBIOS_LEN	4
42 #define	SMBIOS_SIG	"_SM_"
43 
44 struct smbios_eps {
45 	uint8_t		anchor_string[4];		/* '_SM_' */
46 	uint8_t		checksum;
47 	uint8_t		length;
48 	uint8_t		major_version;
49 	uint8_t		minor_version;
50 	uint16_t	maximum_structure_size;
51 	uint8_t		entry_point_revision;
52 	uint8_t		formatted_area[5];
53 	uint8_t		intermediate_anchor_string[5];	/* '_DMI_' */
54 	uint8_t		intermediate_checksum;
55 	uint16_t	structure_table_length;
56 	uint32_t	structure_table_address;
57 	uint16_t	number_structures;
58 	uint8_t		BCD_revision;
59 } __packed;
60 
61 struct smbios_structure_header {
62 	uint8_t		type;
63 	uint8_t		length;
64 	uint16_t	handle;
65 } __packed;
66 
67 typedef void (*smbios_callback_t)(struct smbios_structure_header *, void *);
68 
69 static inline void
70 smbios_walk_table(uint8_t *p, int entries, smbios_callback_t cb, void *arg)
71 {
72 	struct smbios_structure_header *s;
73 
74 	while (entries--) {
75 		s = (struct smbios_structure_header *)p;
76 		cb(s, arg);
77 
78 		/*
79 		 * Look for a double-nul after the end of the
80 		 * formatted area of this structure.
81 		 */
82 		p += s->length;
83 		while (!(p[0] == 0 && p[1] == 0))
84 			p++;
85 
86 		/*
87 		 * Skip over the double-nul to the start of the next
88 		 * structure.
89 		 */
90 		p += 2;
91 	}
92 }
93 
94 #endif /* _SMBIOS_H_ */
95