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,
25 * Partly based on msbios.c from rolo 1.6:
26 *----------------------------------------------------------------------
28 * Sysgo Real-Time Solutions GmbH
29 * Klein-Winternheim, Germany
30 *----------------------------------------------------------------------
35 #include <asm/realmode.h>
39 DECLARE_GLOBAL_DATA_PTR;
43 static int set_jmp_vector(int entry_point, void *target)
45 if (entry_point & ~0xffff)
48 if (((u32)target - 0xf0000) & ~0xffff)
51 printf("set_jmp_vector: 0xf000:%04x -> %p\n",
55 writeb(0xea, 0xf0000 + entry_point);
58 writew(((u32)target-0xf0000), 0xf0000 + entry_point + 1);
61 writew(0xf000, 0xf0000 + entry_point + 3);
66 /* Install an interrupt vector */
67 static void setvector(int vector, u16 segment, void *handler)
69 u16 *ptr = (u16 *)(vector * 4);
70 ptr[0] = ((u32)handler - (segment << 4)) & 0xffff;
74 printf("setvector: int%02x -> %04x:%04x\n",
75 vector, ptr[1], ptr[0]);
81 /* The BIOS section is not relocated and still in the ROM. */
82 ulong bios_start = (ulong)&__bios_start;
83 ulong bios_size = (ulong)&__bios_size;
88 struct pci_controller *pri_hose;
95 if (bios_size > 65536) {
96 printf("BIOS too large (%ld bytes, max is 65536)\n",
101 memcpy(BIOS_BASE, (void *)bios_start, bios_size);
104 memset(BIOS_DATA, 0, BIOS_DATA_SIZE);
106 /* enter some values to the bda */
107 writew(0x3f8, BIOS_DATA); /* com1 addr */
108 writew(0x2f8, BIOS_DATA+2); /* com2 addr */
109 writew(0x3e8, BIOS_DATA+4); /* com3 addr */
110 writew(0x2e8, BIOS_DATA+6); /* com4 addr */
111 writew(0x278, BIOS_DATA+8); /* lpt1 addr */
113 * The kernel wants to read the base memory size
114 * from 40:13. Put a zero there to avoid an error message
116 writew(0, BIOS_DATA+0x13); /* base memory size */
119 /* setup realmode interrupt vectors */
120 for (vector = 0; vector < NUMVECTS; vector++)
121 setvector(vector, BIOS_CS, &rm_def_int);
123 setvector(0x00, BIOS_CS, &rm_int00);
124 setvector(0x01, BIOS_CS, &rm_int01);
125 setvector(0x02, BIOS_CS, &rm_int02);
126 setvector(0x03, BIOS_CS, &rm_int03);
127 setvector(0x04, BIOS_CS, &rm_int04);
128 setvector(0x05, BIOS_CS, &rm_int05);
129 setvector(0x06, BIOS_CS, &rm_int06);
130 setvector(0x07, BIOS_CS, &rm_int07);
131 setvector(0x08, BIOS_CS, &rm_int08);
132 setvector(0x09, BIOS_CS, &rm_int09);
133 setvector(0x0a, BIOS_CS, &rm_int0a);
134 setvector(0x0b, BIOS_CS, &rm_int0b);
135 setvector(0x0c, BIOS_CS, &rm_int0c);
136 setvector(0x0d, BIOS_CS, &rm_int0d);
137 setvector(0x0e, BIOS_CS, &rm_int0e);
138 setvector(0x0f, BIOS_CS, &rm_int0f);
139 setvector(0x10, BIOS_CS, &rm_int10);
140 setvector(0x11, BIOS_CS, &rm_int11);
141 setvector(0x12, BIOS_CS, &rm_int12);
142 setvector(0x13, BIOS_CS, &rm_int13);
143 setvector(0x14, BIOS_CS, &rm_int14);
144 setvector(0x15, BIOS_CS, &rm_int15);
145 setvector(0x16, BIOS_CS, &rm_int16);
146 setvector(0x17, BIOS_CS, &rm_int17);
147 setvector(0x18, BIOS_CS, &rm_int18);
148 setvector(0x19, BIOS_CS, &rm_int19);
149 setvector(0x1a, BIOS_CS, &rm_int1a);
150 setvector(0x1b, BIOS_CS, &rm_int1b);
151 setvector(0x1c, BIOS_CS, &rm_int1c);
152 setvector(0x1d, BIOS_CS, &rm_int1d);
153 setvector(0x1e, BIOS_CS, &rm_int1e);
154 setvector(0x1f, BIOS_CS, &rm_int1f);
156 set_jmp_vector(0xfff0, &realmode_reset);
157 set_jmp_vector(0xfe6e, &realmode_pci_bios_call_entry);
159 /* fill in data area */
160 RELOC_16_WORD(0xf000, ram_in_64kb_chunks) = gd->ram_size >> 16;
161 RELOC_16_WORD(0xf000, bios_equipment) = 0; /* FixMe */
163 /* If we assume only one PCI hose, this PCI hose
164 * will own PCI bus #0, and the last PCI bus of
165 * that PCI hose will be the last PCI bus in the
167 * (This, ofcause break on multi hose systems,
168 * but our PCI BIOS only support one hose anyway)
171 pri_hose = pci_bus_to_hose(0);
172 if (NULL != pri_hose) {
173 /* fill in last pci bus number for use by the realmode
175 RELOC_16_BYTE(0xf000, pci_last_bus) = pri_hose->last_busno;