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
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
|
// Variable layouts of bios.
//
// Copyright (C) 2008 Kevin O'Connor <kevin@koconnor.net>
//
// This file may be distributed under the terms of the GNU GPLv3 license.
#include "types.h" // u8
#include "farptr.h" // SET_SEG
/****************************************************************
* Bios Data Area (BDA)
****************************************************************/
struct ivec {
u16 offset;
u16 seg;
};
struct bios_data_area_s {
// 00:00
struct ivec ivecs[256];
// 30:00
// u8 stack[256];
// 40:00
u16 port_com1, port_com2, port_com3, port_com4;
u16 port_lpt1, port_lpt2, port_lpt3;
u16 ebda_seg;
// 40:10
u16 equipment_list_flags;
u8 pad1;
u16 mem_size_kb;
u8 pad2;
u8 ps2_ctrl_flag;
u8 kbd_flag0;
u8 kbd_flag1;
u8 alt_keypad;
u16 kbd_buf_head;
u16 kbd_buf_tail;
// 40:1e
u8 kbd_buf[32];
u8 floppy_recalibration_status;
u8 floppy_motor_status;
// 40:40
u8 floppy_motor_counter;
u8 floppy_last_status;
u8 floppy_return_status[7];
u8 other1[0x7];
// 40:50
u8 other2[0x1c];
// 40:6c
u32 timer_counter;
// 40:70
u8 timer_rollover;
u8 other4[0x0f];
// 40:80
u16 kbd_buf_start_offset;
u16 kbd_buf_end_offset;
u8 other5[7];
u8 floppy_last_data_rate;
u8 other6[3];
u8 floppy_harddisk_info;
// 40:90
u8 floppy_media_state[4];
u8 floppy_track0;
u8 floppy_track1;
u8 kbd_mode;
u8 kbd_led;
u32 ptr_user_wait_complete_flag;
u32 user_wait_timeout;
// 40:A0
u8 rtc_wait_flag;
} __attribute__((packed));
// BDA floppy_recalibration_status bitdefs
#define FRS_TIMEOUT (1<<7)
// BDA rtc_wait_flag bitdefs
#define RWS_WAIT_PENDING (1<<0)
#define RWS_WAIT_ELAPSED (1<<7)
// BDA floppy_media_state bitdefs
#define FMS_DRIVE_STATE_MASK (0x07)
#define FMS_MEDIA_DRIVE_ESTABLISHED (1<<4)
#define FMS_DOUBLE_STEPPING (1<<5)
#define FMS_DATA_RATE_MASK (0xc0)
// Accessor functions
#define GET_BDA(var) \
GET_FARVAR(0x0000, ((struct bios_data_area_s *)0)->var)
#define SET_BDA(var, val) \
SET_FARVAR(0x0000, ((struct bios_data_area_s *)0)->var, (val))
#define CLEARBITS_BDA(var, val) do { \
typeof(((struct bios_data_area_s *)0)->var) __val = GET_BDA(var); \
SET_BDA(var, (__val & ~(val))); \
} while (0)
#define SETBITS_BDA(var, val) do { \
typeof(((struct bios_data_area_s *)0)->var) __val = GET_BDA(var); \
SET_BDA(var, (__val | (val))); \
} while (0)
/****************************************************************
* Extended Bios Data Area (EBDA)
****************************************************************/
struct extended_bios_data_area_s {
u8 size;
u8 other1[0x3c];
// FDPT - Can be splitted in data members if needed
u8 fdpt0[0x10];
u8 fdpt1[0x10];
u8 other2[0xC4];
// ATA Driver data
//ata_t ata;
#if BX_ELTORITO_BOOT
// El Torito Emulation data
cdemu_t cdemu;
#endif // BX_ELTORITO_BOOT
};
/****************************************************************
* Extended Bios Data Area (EBDA)
****************************************************************/
#define UREG(ER, R, RH, RL) union { u32 ER; struct { u16 R; u16 R ## _hi; }; struct { u8 RL; u8 RH; u8 R ## _hilo; u8 R ## _hihi; }; }
struct bregs {
u16 ds;
u16 es;
UREG(edi, di, di_hi, di_lo);
UREG(esi, si, si_hi, si_lo);
UREG(ebp, bp, bp_hi, bp_lo);
UREG(esp, sp, sp_hi, sp_lo);
UREG(ebx, bx, bh, bl);
UREG(edx, dx, dh, dl);
UREG(ecx, cx, ch, cl);
UREG(eax, ax, ah, al);
u16 ip;
u16 cs;
u16 flags;
} __attribute__((packed));
// bregs flags bitdefs
#define F_ZF (1<<6)
#define F_CF (1<<0)
static inline void
set_cf(struct bregs *regs, int cond)
{
if (cond)
regs->flags |= F_CF;
else
regs->flags &= ~F_CF;
}
/****************************************************************
* Bios Config Table
****************************************************************/
struct bios_config_table_s {
// XXX
u8 x;
};
extern struct bios_config_table_s BIOS_CONFIG_TABLE;
/****************************************************************
* Memory layout info
****************************************************************/
#define SEG_BIOS 0xf000
#define EBDA_SEG 0x9FC0
#define EBDA_SIZE 1 // In KiB
#define BASE_MEM_IN_K (640 - EBDA_SIZE)
|
