3 * Daniel Engström, Omicron Ceti AB, daniel@omicron.se
5 * See file CREDITS for list of people who contributed to this
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of
11 * the License, or (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
26 * Partly based on msbios.c from rolo 1.6:
27 *----------------------------------------------------------------------
29 * Sysgo Real-Time Solutions GmbH
30 * Klein-Winternheim, Germany
31 *----------------------------------------------------------------------
35 #include <asm/realmode.h>
40 #define BIOS_DATA ((char*)0x400)
41 #define BIOS_DATA_SIZE 256
42 #define BIOS_BASE ((char*)0xf0000)
43 #define BIOS_CS 0xf000
45 extern u16 ram_in_64kb_chunks;
46 extern u16 bios_equipment;
47 extern void *rm_int00;
48 extern void *rm_int01;
49 extern void *rm_int02;
50 extern void *rm_int03;
51 extern void *rm_int04;
52 extern void *rm_int05;
53 extern void *rm_int06;
54 extern void *rm_int07;
55 extern void *rm_int08;
56 extern void *rm_int09;
57 extern void *rm_int0a;
58 extern void *rm_int0b;
59 extern void *rm_int0c;
60 extern void *rm_int0d;
61 extern void *rm_int0e;
62 extern void *rm_int0f;
63 extern void *rm_int10;
64 extern void *rm_int11;
65 extern void *rm_int12;
66 extern void *rm_int13;
67 extern void *rm_int14;
68 extern void *rm_int15;
69 extern void *rm_int16;
70 extern void *rm_int17;
71 extern void *rm_int18;
72 extern void *rm_int19;
73 extern void *rm_int1a;
74 extern void *rm_int1b;
75 extern void *rm_int1c;
76 extern void *rm_int1d;
77 extern void *rm_int1e;
78 extern void *rm_int1f;
79 extern void *rm_def_int;
82 ************************************************************
83 * Install an interrupt vector
84 ************************************************************
87 static void setvector(int vector, u16 segment, void *handler)
89 u16 *ptr = (u16*)(vector*4);
90 ptr[0] = ((u32)handler - (segment << 4))&0xffff;
94 printf("setvector: int%02x -> %04x:%04x\n",
95 vector, ptr[1], ptr[0]);
101 DECLARE_GLOBAL_DATA_PTR;
110 if (i386boot_bios_size > 65536) {
111 printf("BIOS too large (%ld bytes, max is 65536)\n",
116 memcpy(BIOS_BASE, (void*)i386boot_bios, i386boot_bios_size);
119 memset(BIOS_DATA, 0, BIOS_DATA_SIZE);
121 /* enter some values to the bda */
122 writew(0x3f8, BIOS_DATA); /* com1 addr */
123 writew(0x2f8, BIOS_DATA+2); /* com2 addr */
124 writew(0x3e8, BIOS_DATA+4); /* com3 addr */
125 writew(0x2e8, BIOS_DATA+6); /* com4 addr */
126 writew(0x278, BIOS_DATA+8); /* lpt1 addr */
128 * The kernel wants to read the base memory size
129 * from 40:13. Put a zero there to avoid an error message
131 writew(0, BIOS_DATA+0x13); /* base memory size */
134 /* setup realmode interrupt vectors */
135 for (vector = 0; vector < NUMVECTS; vector++) {
136 setvector(vector, BIOS_CS, &rm_def_int);
139 setvector(0x00, BIOS_CS, &rm_int00);
140 setvector(0x01, BIOS_CS, &rm_int01);
141 setvector(0x02, BIOS_CS, &rm_int02);
142 setvector(0x03, BIOS_CS, &rm_int03);
143 setvector(0x04, BIOS_CS, &rm_int04);
144 setvector(0x05, BIOS_CS, &rm_int05);
145 setvector(0x06, BIOS_CS, &rm_int06);
146 setvector(0x07, BIOS_CS, &rm_int07);
147 setvector(0x08, BIOS_CS, &rm_int08);
148 setvector(0x09, BIOS_CS, &rm_int09);
149 setvector(0x0a, BIOS_CS, &rm_int0a);
150 setvector(0x0b, BIOS_CS, &rm_int0b);
151 setvector(0x0c, BIOS_CS, &rm_int0c);
152 setvector(0x0d, BIOS_CS, &rm_int0d);
153 setvector(0x0e, BIOS_CS, &rm_int0e);
154 setvector(0x0f, BIOS_CS, &rm_int0f);
155 setvector(0x10, BIOS_CS, &rm_int10);
156 setvector(0x11, BIOS_CS, &rm_int11);
157 setvector(0x12, BIOS_CS, &rm_int12);
158 setvector(0x13, BIOS_CS, &rm_int13);
159 setvector(0x14, BIOS_CS, &rm_int14);
160 setvector(0x15, BIOS_CS, &rm_int15);
161 setvector(0x16, BIOS_CS, &rm_int16);
162 setvector(0x17, BIOS_CS, &rm_int17);
163 setvector(0x18, BIOS_CS, &rm_int18);
164 setvector(0x19, BIOS_CS, &rm_int19);
165 setvector(0x1a, BIOS_CS, &rm_int1a);
166 setvector(0x1b, BIOS_CS, &rm_int1b);
167 setvector(0x1c, BIOS_CS, &rm_int1c);
168 setvector(0x1d, BIOS_CS, &rm_int1d);
169 setvector(0x1e, BIOS_CS, &rm_int1e);
170 setvector(0x1f, BIOS_CS, &rm_int1f);
172 /* fill in data area */
173 ram_in_64kb_chunks = gd->ram_size >> 16;
174 bios_equipment = 0; /* FixMe */