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
|
/*
* (C) Copyright 2002
* Daniel Engström, Omicron Ceti AB, daniel@omicron.se
*
* See file CREDITS for list of people who contributed to this
* project.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License, or (at your option) any later version.
*
* This program 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston,
* MA 02111-1307 USA
*/
#ifndef _BIOS_H_
#define _BIOS_H_
#define OFFS_ES 0 /* 16bit */
#define OFFS_GS 2 /* 16bit */
#define OFFS_DS 4 /* 16bit */
#define OFFS_EDI 6 /* 32bit */
#define OFFS_DI 6 /* low 16 bits of EDI */
#define OFFS_ESI 10 /* 32bit */
#define OFFS_SI 10 /* low 16 bits of ESI */
#define OFFS_EBP 14 /* 32bit */
#define OFFS_BP 14 /* low 16 bits of EBP */
#define OFFS_ESP 18 /* 32bit */
#define OFFS_SP 18 /* low 16 bits of ESP */
#define OFFS_EBX 22 /* 32bit */
#define OFFS_BX 22 /* low 16 bits of EBX */
#define OFFS_BL 22 /* low 8 bits of BX */
#define OFFS_BH 23 /* high 8 bits of BX */
#define OFFS_EDX 26 /* 32bit */
#define OFFS_DX 26 /* low 16 bits of EBX */
#define OFFS_DL 26 /* low 8 bits of BX */
#define OFFS_DH 27 /* high 8 bits of BX */
#define OFFS_ECX 30 /* 32bit */
#define OFFS_CX 30 /* low 16 bits of EBX */
#define OFFS_CL 30 /* low 8 bits of BX */
#define OFFS_CH 31 /* high 8 bits of BX */
#define OFFS_EAX 34 /* 32bit */
#define OFFS_AX 34 /* low 16 bits of EBX */
#define OFFS_AL 34 /* low 8 bits of BX */
#define OFFS_AH 35 /* high 8 bits of BX */
#define OFFS_VECTOR 38 /* 16bit */
#define OFFS_IP 40 /* 16bit */
#define OFFS_CS 42 /* 16bit */
#define OFFS_FLAGS 44 /* 16bit */
#define SEGMENT 0x40
#define STACK 0x800 /* stack at 0x40:0x800 -> 0x800 */
/* save general registers */
/* save some segments */
/* save callers stack segment .. */
/* ... in gs */
/* setup my segments */
/* setup BIOS stackpointer */
#define MAKE_BIOS_STACK \
pushal ; \
pushw %ds ; \
pushw %gs ; \
pushw %es ; \
pushw %ss ; \
popw %gs ; \
movw $SEGMENT,%ax ; \
movw %ax,%ds ; \
movw %ax,%es ; \
movw %ax,%ss ; \
movw %sp,%bp ; \
movw $STACK,%sp
#define RESTORE_CALLERS_STACK \
pushw %gs ; /* restore callers stack segment */ \
popw %ss ; \
movw %bp,%sp ; /* restore stackpointer */ \
\
popw %es ; /* restore segment selectors */ \
popw %gs ; \
popw %ds ; \
\
popal /* restore GP registers */
#endif
|