1 /*
2 * (C) Copyright 2002
3 * Daniel Engstr�m, Omicron Ceti AB, daniel@omicron.se
4 *
5 * See file CREDITS for list of people who contributed to this
6 * project.
7 *
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.
12 *
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.
17 *
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,
21 * MA 02111-1307 USA
22 */
23
24
25 /*
26 * Partly based on msbios.c from rolo 1.6:
27 *----------------------------------------------------------------------
28 * (C) Copyright 2000
29 * Sysgo Real-Time Solutions GmbH
30 * Klein-Winternheim, Germany
31 *----------------------------------------------------------------------
32 */
33
34 #include <common.h>
35 #include <pci.h>
36 #include <asm/realmode.h>
37 #include <asm/io.h>
38
39 DECLARE_GLOBAL_DATA_PTR;
40
41 #define NUMVECTS 256
42
43 #define BIOS_DATA ((char*)0x400)
44 #define BIOS_DATA_SIZE 256
45 #define BIOS_BASE ((char*)0xf0000)
46 #define BIOS_CS 0xf000
47
48 extern ulong _i386boot_bios;
49 extern ulong _i386boot_bios_size;
50
51 /* these are defined in a 16bit segment and needs
52 * to be accessed with the RELOC_16_xxxx() macros below
53 */
54 extern u16 ram_in_64kb_chunks;
55 extern u16 bios_equipment;
56 extern u8 pci_last_bus;
57
58 extern void *rm_int00;
59 extern void *rm_int01;
60 extern void *rm_int02;
61 extern void *rm_int03;
62 extern void *rm_int04;
63 extern void *rm_int05;
64 extern void *rm_int06;
65 extern void *rm_int07;
66 extern void *rm_int08;
67 extern void *rm_int09;
68 extern void *rm_int0a;
69 extern void *rm_int0b;
70 extern void *rm_int0c;
71 extern void *rm_int0d;
72 extern void *rm_int0e;
73 extern void *rm_int0f;
74 extern void *rm_int10;
75 extern void *rm_int11;
76 extern void *rm_int12;
77 extern void *rm_int13;
78 extern void *rm_int14;
79 extern void *rm_int15;
80 extern void *rm_int16;
81 extern void *rm_int17;
82 extern void *rm_int18;
83 extern void *rm_int19;
84 extern void *rm_int1a;
85 extern void *rm_int1b;
86 extern void *rm_int1c;
87 extern void *rm_int1d;
88 extern void *rm_int1e;
89 extern void *rm_int1f;
90 extern void *rm_def_int;
91
92 extern void *realmode_reset;
93 extern void *realmode_pci_bios_call_entry;
94
set_jmp_vector(int entry_point,void * target)95 static int set_jmp_vector(int entry_point, void *target)
96 {
97 if (entry_point & ~0xffff) {
98 return -1;
99 }
100
101 if (((u32)target-0xf0000) & ~0xffff) {
102 return -1;
103 }
104 printf("set_jmp_vector: 0xf000:%04x -> %p\n",
105 entry_point, target);
106
107 /* jmp opcode */
108 writeb(0xea, 0xf0000 + entry_point);
109
110 /* offset */
111 writew(((u32)target-0xf0000), 0xf0000 + entry_point + 1);
112
113 /* segment */
114 writew(0xf000, 0xf0000 + entry_point + 3);
115
116 return 0;
117 }
118
119
120 /*
121 ************************************************************
122 * Install an interrupt vector
123 ************************************************************
124 */
125
setvector(int vector,u16 segment,void * handler)126 static void setvector(int vector, u16 segment, void *handler)
127 {
128 u16 *ptr = (u16*)(vector*4);
129 ptr[0] = ((u32)handler - (segment << 4))&0xffff;
130 ptr[1] = segment;
131
132 #if 0
133 printf("setvector: int%02x -> %04x:%04x\n",
134 vector, ptr[1], ptr[0]);
135 #endif
136 }
137
138 #define RELOC_16_LONG(seg, off) *(u32*)(seg << 4 | (u32)&off)
139 #define RELOC_16_WORD(seg, off) *(u16*)(seg << 4 | (u32)&off)
140 #define RELOC_16_BYTE(seg, off) *(u8*)(seg << 4 | (u32)&off)
141
bios_setup(void)142 int bios_setup(void)
143 {
144 ulong i386boot_bios = (ulong)&_i386boot_bios + gd->reloc_off;
145 ulong i386boot_bios_size = (ulong)&_i386boot_bios_size;
146
147 static int done=0;
148 int vector;
149 #ifdef CONFIG_PCI
150 struct pci_controller *pri_hose;
151 #endif
152 if (done) {
153 return 0;
154 }
155 done = 1;
156
157 if (i386boot_bios_size > 65536) {
158 printf("BIOS too large (%ld bytes, max is 65536)\n",
159 i386boot_bios_size);
160 return -1;
161 }
162
163 memcpy(BIOS_BASE, (void*)i386boot_bios, i386boot_bios_size);
164
165 /* clear bda */
166 memset(BIOS_DATA, 0, BIOS_DATA_SIZE);
167
168 /* enter some values to the bda */
169 writew(0x3f8, BIOS_DATA); /* com1 addr */
170 writew(0x2f8, BIOS_DATA+2); /* com2 addr */
171 writew(0x3e8, BIOS_DATA+4); /* com3 addr */
172 writew(0x2e8, BIOS_DATA+6); /* com4 addr */
173 writew(0x278, BIOS_DATA+8); /* lpt1 addr */
174 /*
175 * The kernel wants to read the base memory size
176 * from 40:13. Put a zero there to avoid an error message
177 */
178 writew(0, BIOS_DATA+0x13); /* base memory size */
179
180
181 /* setup realmode interrupt vectors */
182 for (vector = 0; vector < NUMVECTS; vector++) {
183 setvector(vector, BIOS_CS, &rm_def_int);
184 }
185
186 setvector(0x00, BIOS_CS, &rm_int00);
187 setvector(0x01, BIOS_CS, &rm_int01);
188 setvector(0x02, BIOS_CS, &rm_int02);
189 setvector(0x03, BIOS_CS, &rm_int03);
190 setvector(0x04, BIOS_CS, &rm_int04);
191 setvector(0x05, BIOS_CS, &rm_int05);
192 setvector(0x06, BIOS_CS, &rm_int06);
193 setvector(0x07, BIOS_CS, &rm_int07);
194 setvector(0x08, BIOS_CS, &rm_int08);
195 setvector(0x09, BIOS_CS, &rm_int09);
196 setvector(0x0a, BIOS_CS, &rm_int0a);
197 setvector(0x0b, BIOS_CS, &rm_int0b);
198 setvector(0x0c, BIOS_CS, &rm_int0c);
199 setvector(0x0d, BIOS_CS, &rm_int0d);
200 setvector(0x0e, BIOS_CS, &rm_int0e);
201 setvector(0x0f, BIOS_CS, &rm_int0f);
202 setvector(0x10, BIOS_CS, &rm_int10);
203 setvector(0x11, BIOS_CS, &rm_int11);
204 setvector(0x12, BIOS_CS, &rm_int12);
205 setvector(0x13, BIOS_CS, &rm_int13);
206 setvector(0x14, BIOS_CS, &rm_int14);
207 setvector(0x15, BIOS_CS, &rm_int15);
208 setvector(0x16, BIOS_CS, &rm_int16);
209 setvector(0x17, BIOS_CS, &rm_int17);
210 setvector(0x18, BIOS_CS, &rm_int18);
211 setvector(0x19, BIOS_CS, &rm_int19);
212 setvector(0x1a, BIOS_CS, &rm_int1a);
213 setvector(0x1b, BIOS_CS, &rm_int1b);
214 setvector(0x1c, BIOS_CS, &rm_int1c);
215 setvector(0x1d, BIOS_CS, &rm_int1d);
216 setvector(0x1e, BIOS_CS, &rm_int1e);
217 setvector(0x1f, BIOS_CS, &rm_int1f);
218
219 set_jmp_vector(0xfff0, &realmode_reset);
220 set_jmp_vector(0xfe6e, &realmode_pci_bios_call_entry);
221
222 /* fill in data area */
223 RELOC_16_WORD(0xf000, ram_in_64kb_chunks) = gd->ram_size >> 16;
224 RELOC_16_WORD(0xf000, bios_equipment) = 0; /* FixMe */
225
226 /* If we assume only one PCI hose, this PCI hose
227 * will own PCI bus #0, and the last PCI bus of
228 * that PCI hose will be the last PCI bus in the
229 * system.
230 * (This, ofcause break on multi hose systems,
231 * but our PCI BIOS only support one hose anyway)
232 */
233 #ifdef CONFIG_PCI
234 pri_hose = pci_bus_to_hose(0);
235 if (NULL != pri_hose) {
236 /* fill in last pci bus number for use by the realmode
237 * PCI BIOS */
238 RELOC_16_BYTE(0xf000, pci_last_bus) = pri_hose->last_busno;
239 }
240 #endif
241 return 0;
242 }
243