xref: /freebsd/sys/dev/smbios/smbios.h (revision 2008043f386721d58158e37e0d7e50df8095942d)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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 
30 #ifndef _SMBIOS_H_
31 #define _SMBIOS_H_
32 
33 /*
34  * System Management BIOS
35  */
36 #define	SMBIOS_START	0xf0000
37 #define	SMBIOS_STEP	0x10
38 #define	SMBIOS_OFF	0
39 #define	SMBIOS_LEN	4
40 #define	SMBIOS_SIG	"_SM_"
41 
42 struct smbios_eps {
43 	uint8_t		anchor_string[4];		/* '_SM_' */
44 	uint8_t		checksum;
45 	uint8_t		length;
46 	uint8_t		major_version;
47 	uint8_t		minor_version;
48 	uint16_t	maximum_structure_size;
49 	uint8_t		entry_point_revision;
50 	uint8_t		formatted_area[5];
51 	uint8_t		intermediate_anchor_string[5];	/* '_DMI_' */
52 	uint8_t		intermediate_checksum;
53 	uint16_t	structure_table_length;
54 	uint32_t	structure_table_address;
55 	uint16_t	number_structures;
56 	uint8_t		BCD_revision;
57 } __packed;
58 
59 struct smbios_structure_header {
60 	uint8_t		type;
61 	uint8_t		length;
62 	uint16_t	handle;
63 } __packed;
64 
65 typedef void (*smbios_callback_t)(struct smbios_structure_header *, void *);
66 
67 static inline void
68 smbios_walk_table(uint8_t *p, int entries, smbios_callback_t cb, void *arg)
69 {
70 	struct smbios_structure_header *s;
71 
72 	while (entries--) {
73 		s = (struct smbios_structure_header *)p;
74 		cb(s, arg);
75 
76 		/*
77 		 * Look for a double-nul after the end of the
78 		 * formatted area of this structure.
79 		 */
80 		p += s->length;
81 		while (!(p[0] == 0 && p[1] == 0))
82 			p++;
83 
84 		/*
85 		 * Skip over the double-nul to the start of the next
86 		 * structure.
87 		 */
88 		p += 2;
89 	}
90 }
91 
92 #ifdef _KERNEL
93 void identify_hypervisor_smbios(void);
94 #endif
95 
96 #endif /* _SMBIOS_H_ */
97