biossmap.c revision 173118 
1/*-
2 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/sys/boot/i386/libi386/biossmap.c 173118 2007-10-28 21:23:49Z jhb $");
29
30/*
31 * Obtain memory configuration information from the BIOS
32 */
33#include <stand.h>
34#include <sys/param.h>
35#include <sys/linker.h>
36#include <machine/metadata.h>
37#include <machine/pc/bios.h>
38#include "bootstrap.h"
39#include "libi386.h"
40#include "btxv86.h"
41
42static struct bios_smap smap;
43
44static struct bios_smap *smapbase;
45static int smaplen;
46
47void
48bios_getsmap(void)
49{
50	int n;
51
52	n = 0;
53	smaplen = 0;
54	/* Count up segments in system memory map */
55	v86.ebx = 0;
56	do {
57		v86.ctl = V86_FLAGS;
58		v86.addr = 0x15;		/* int 0x15 function 0xe820*/
59		v86.eax = 0xe820;
60		v86.ecx = sizeof(struct bios_smap);
61		v86.edx = SMAP_SIG;
62		v86.es = VTOPSEG(&smap);
63		v86.edi = VTOPOFF(&smap);
64		v86int();
65		if ((v86.efl & 1) || (v86.eax != SMAP_SIG))
66			break;
67		n++;
68	} while (v86.ebx != 0);
69	if (n == 0)
70		return;
71	n += 10;	/* spare room */
72	smapbase = malloc(n * sizeof(*smapbase));
73
74	/* Save system memory map */
75	v86.ebx = 0;
76	do {
77		v86.ctl = V86_FLAGS;
78		v86.addr = 0x15;		/* int 0x15 function 0xe820*/
79		v86.eax = 0xe820;
80		v86.ecx = sizeof(struct bios_smap);
81		v86.edx = SMAP_SIG;
82		v86.es = VTOPSEG(&smap);
83		v86.edi = VTOPOFF(&smap);
84		v86int();
85		bcopy(&smap, &smapbase[smaplen], sizeof(struct bios_smap));
86		smaplen++;
87		if ((v86.efl & 1) || (v86.eax != SMAP_SIG))
88			break;
89	} while (v86.ebx != 0 && smaplen < n);
90}
91
92void
93bios_addsmapdata(struct preloaded_file *kfp)
94{
95	int len;
96
97	if (smapbase == 0 || smaplen == 0)
98		return;
99	len = smaplen * sizeof(*smapbase);
100	file_addmetadata(kfp, MODINFOMD_SMAP, len, smapbase);
101}
102
103COMMAND_SET(smap, "smap", "show BIOS SMAP", command_smap);
104
105static int
106command_smap(int argc, char *argv[])
107{
108	int i;
109
110	if (smapbase == 0 || smaplen == 0)
111		return (CMD_ERROR);
112	for (i = 0; i < smaplen; i++)
113		printf("SMAP type=%02x base=%016llx len=%016llx\n",
114		    smapbase[i].type, smapbase[i].base, smapbase[i].length);
115	return (CMD_OK);
116}
117