blob: c3b4e597aabfd310b085239eb78ac70b005b703f [file] [log] [blame]
wdenk2262cfe2002-11-18 00:14:45 +00001/*
2 * (C) Copyright 2002
3 * Daniel Engström, Omicron Ceti AB, daniel@omicron.se
wdenk8bde7f72003-06-27 21:31:46 +00004 *
wdenk2262cfe2002-11-18 00:14:45 +00005 * 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
wdenk8bde7f72003-06-27 21:31:46 +000024/*
wdenk2262cfe2002-11-18 00:14:45 +000025 * Linux i386 zImage and bzImage loading
wdenk8bde7f72003-06-27 21:31:46 +000026 *
27 * based on the procdure described in
wdenk2262cfe2002-11-18 00:14:45 +000028 * linux/Documentation/i386/boot.txt
29 */
30
31#include <common.h>
32#include <asm/io.h>
33#include <asm/ptrace.h>
34#include <asm/zimage.h>
35#include <asm/realmode.h>
36#include <asm/byteorder.h>
37
38/*
39 * Memory lay-out:
wdenk8bde7f72003-06-27 21:31:46 +000040 *
wdenk2262cfe2002-11-18 00:14:45 +000041 * relative to setup_base (which is 0x90000 currently)
wdenk8bde7f72003-06-27 21:31:46 +000042 *
43 * 0x0000-0x7FFF Real mode kernel
wdenk2262cfe2002-11-18 00:14:45 +000044 * 0x8000-0x8FFF Stack and heap
45 * 0x9000-0x90FF Kernel command line
46 */
47#define DEFAULT_SETUP_BASE 0x90000
48#define COMMAND_LINE_OFFSET 0x9000
49#define HEAP_END_OFFSET 0x8e00
50
51#define COMMAND_LINE_SIZE 2048
52
53static void build_command_line(char *command_line, int auto_boot)
54{
55 char *env_command_line;
wdenk8bde7f72003-06-27 21:31:46 +000056
wdenk2262cfe2002-11-18 00:14:45 +000057 command_line[0] = '\0';
wdenk8bde7f72003-06-27 21:31:46 +000058
wdenk2262cfe2002-11-18 00:14:45 +000059 env_command_line = getenv("bootargs");
wdenk8bde7f72003-06-27 21:31:46 +000060
wdenk2262cfe2002-11-18 00:14:45 +000061 /* set console= argument if we use a serial console */
62 if (NULL == strstr(env_command_line, "console=")) {
63 if (0==strcmp(getenv("stdout"), "serial")) {
wdenk8bde7f72003-06-27 21:31:46 +000064
wdenk2262cfe2002-11-18 00:14:45 +000065 /* We seem to use serial console */
wdenk8bde7f72003-06-27 21:31:46 +000066 sprintf(command_line, "console=ttyS0,%s ",
wdenk2262cfe2002-11-18 00:14:45 +000067 getenv("baudrate"));
68 }
69 }
wdenk8bde7f72003-06-27 21:31:46 +000070
wdenk2262cfe2002-11-18 00:14:45 +000071 if (auto_boot) {
72 strcat(command_line, "auto ");
73 }
wdenk8bde7f72003-06-27 21:31:46 +000074
wdenk2262cfe2002-11-18 00:14:45 +000075 if (NULL != env_command_line) {
76 strcat(command_line, env_command_line);
wdenk8bde7f72003-06-27 21:31:46 +000077 }
78
79
wdenk2262cfe2002-11-18 00:14:45 +000080 printf("Kernel command line: \"%s\"\n", command_line);
81}
82
wdenk8bde7f72003-06-27 21:31:46 +000083void *load_zimage(char *image, unsigned long kernel_size,
wdenk2262cfe2002-11-18 00:14:45 +000084 unsigned long initrd_addr, unsigned long initrd_size,
85 int auto_boot)
86{
wdenk8bde7f72003-06-27 21:31:46 +000087 void *setup_base;
wdenk2262cfe2002-11-18 00:14:45 +000088 int setup_size;
89 int bootproto;
90 int big_image;
91 void *load_address;
wdenk8bde7f72003-06-27 21:31:46 +000092
93
wdenk2262cfe2002-11-18 00:14:45 +000094 setup_base = (void*)DEFAULT_SETUP_BASE; /* base address for real-mode segment */
wdenk8bde7f72003-06-27 21:31:46 +000095
96 if (KERNEL_MAGIC != *(u16*)(image + BOOT_FLAG_OFF)) {
wdenk2262cfe2002-11-18 00:14:45 +000097 printf("Error: Invalid kernel magic (found 0x%04x, expected 0xaa55)\n",
98 *(u16*)(image + BOOT_FLAG_OFF));
99 return 0;
100 }
wdenk8bde7f72003-06-27 21:31:46 +0000101
102
wdenk2262cfe2002-11-18 00:14:45 +0000103 /* determine boot protocol version */
104 if (KERNEL_V2_MAGIC == *(u32*)(image+HEADER_OFF)) {
105 bootproto = *(u16*)(image+VERSION_OFF);
106 } else {
107 /* Very old kernel */
108 bootproto = 0x0100;
109 }
wdenk8bde7f72003-06-27 21:31:46 +0000110
wdenk2262cfe2002-11-18 00:14:45 +0000111 /* determine size of setup */
112 if (0 == *(u8*)(image + SETUP_SECTS_OFF)) {
113 setup_size = 5 * 512;
114 } else {
115 setup_size = (*(u8*)(image + SETUP_SECTS_OFF) + 1) * 512;
116 }
wdenk8bde7f72003-06-27 21:31:46 +0000117
wdenk2262cfe2002-11-18 00:14:45 +0000118 if (setup_size > SETUP_MAX_SIZE) {
119 printf("Error: Setup is too large (%d bytes)\n", setup_size);
120 }
wdenk8bde7f72003-06-27 21:31:46 +0000121
wdenk2262cfe2002-11-18 00:14:45 +0000122 /* Determine image type */
wdenk8bde7f72003-06-27 21:31:46 +0000123 big_image = (bootproto >= 0x0200) && (*(u8*)(image + LOADFLAGS_OFF) & BIG_KERNEL_FLAG);
124
wdenk2262cfe2002-11-18 00:14:45 +0000125 /* Derermine load address */
126 load_address = (void*)(big_image ? BZIMAGE_LOAD_ADDR:ZIMAGE_LOAD_ADDR);
wdenk8bde7f72003-06-27 21:31:46 +0000127
wdenk2262cfe2002-11-18 00:14:45 +0000128 /* load setup */
129 memmove(setup_base, image, setup_size);
wdenk8bde7f72003-06-27 21:31:46 +0000130
131 printf("Using boot protocol version %x.%02x\n",
wdenk2262cfe2002-11-18 00:14:45 +0000132 (bootproto & 0xff00) >> 8, bootproto & 0xff);
wdenk8bde7f72003-06-27 21:31:46 +0000133
134
135 if (bootproto == 0x0100) {
136
wdenk2262cfe2002-11-18 00:14:45 +0000137 *(u16*)(setup_base + CMD_LINE_MAGIC_OFF) = COMMAND_LINE_MAGIC;
wdenk8bde7f72003-06-27 21:31:46 +0000138 *(u16*)(setup_base + CMD_LINE_OFFSET_OFF) = COMMAND_LINE_OFFSET;
139
wdenk2262cfe2002-11-18 00:14:45 +0000140 /* A very old kernel MUST have its real-mode code
141 * loaded at 0x90000 */
wdenk8bde7f72003-06-27 21:31:46 +0000142
wdenk2262cfe2002-11-18 00:14:45 +0000143 if ((u32)setup_base != 0x90000) {
144 /* Copy the real-mode kernel */
145 memmove((void*)0x90000, setup_base, setup_size);
146 /* Copy the command line */
wdenk8bde7f72003-06-27 21:31:46 +0000147 memmove((void*)0x99000, setup_base+COMMAND_LINE_OFFSET,
wdenk2262cfe2002-11-18 00:14:45 +0000148 COMMAND_LINE_SIZE);
wdenk8bde7f72003-06-27 21:31:46 +0000149
wdenk2262cfe2002-11-18 00:14:45 +0000150 setup_base = (void*)0x90000; /* Relocated */
151 }
wdenk8bde7f72003-06-27 21:31:46 +0000152
wdenk2262cfe2002-11-18 00:14:45 +0000153 /* It is recommended to clear memory up to the 32K mark */
154 memset((void*)0x90000 + setup_size, 0, SETUP_MAX_SIZE-setup_size);
155 }
wdenk8bde7f72003-06-27 21:31:46 +0000156
wdenk2262cfe2002-11-18 00:14:45 +0000157 if (bootproto >= 0x0200) {
158 *(u8*)(setup_base + TYPE_OF_LOADER_OFF) = 0xff;
wdenk8bde7f72003-06-27 21:31:46 +0000159 printf("Linux kernel version %s\n",
160 (char*)(setup_base + SETUP_START_OFFSET +
wdenk2262cfe2002-11-18 00:14:45 +0000161 *(u16*)(setup_base + START_SYS_OFF + 2)));
wdenk8bde7f72003-06-27 21:31:46 +0000162
wdenk2262cfe2002-11-18 00:14:45 +0000163 if (initrd_addr) {
164 printf("Initial RAM disk at linear address 0x%08lx, size %ld bytes\n",
165 initrd_addr, initrd_size);
wdenk8bde7f72003-06-27 21:31:46 +0000166
wdenk2262cfe2002-11-18 00:14:45 +0000167 *(u32*)(setup_base + RAMDISK_IMAGE_OFF) = initrd_addr;
168 *(u32*)(setup_base + RAMDISK_SIZE_OFF)=initrd_size;
169 }
170 }
wdenk8bde7f72003-06-27 21:31:46 +0000171
wdenk2262cfe2002-11-18 00:14:45 +0000172 if (bootproto >= 0x0201) {
173 *(u16*)(setup_base + HEAP_END_PTR_OFF) = HEAP_END_OFFSET;
wdenk8bde7f72003-06-27 21:31:46 +0000174
wdenk2262cfe2002-11-18 00:14:45 +0000175 /* CAN_USE_HEAP */
wdenk8bde7f72003-06-27 21:31:46 +0000176 *(u8*)(setup_base + LOADFLAGS_OFF) =
wdenk2262cfe2002-11-18 00:14:45 +0000177 *(u8*)(setup_base + LOADFLAGS_OFF) | HEAP_FLAG;
178 }
wdenk8bde7f72003-06-27 21:31:46 +0000179
wdenk2262cfe2002-11-18 00:14:45 +0000180 if (bootproto >= 0x0202) {
181 *(u32*)(setup_base + CMD_LINE_PTR_OFF) = (u32)setup_base + COMMAND_LINE_OFFSET;
182 } else if (bootproto >= 0x0200) {
183 *(u16*)(setup_base + CMD_LINE_MAGIC_OFF) = COMMAND_LINE_MAGIC;
wdenk8bde7f72003-06-27 21:31:46 +0000184 *(u16*)(setup_base + CMD_LINE_OFFSET_OFF) = COMMAND_LINE_OFFSET;
wdenk2262cfe2002-11-18 00:14:45 +0000185 *(u16*)(setup_base + SETUP_MOVE_SIZE_OFF) = 0x9100;
186 }
wdenk2262cfe2002-11-18 00:14:45 +0000187
wdenk8bde7f72003-06-27 21:31:46 +0000188
wdenk2262cfe2002-11-18 00:14:45 +0000189 if (big_image) {
wdenk8bde7f72003-06-27 21:31:46 +0000190 if ((kernel_size - setup_size) > BZIMAGE_MAX_SIZE) {
wdenk2262cfe2002-11-18 00:14:45 +0000191 printf("Error: bzImage kernel too big! (size: %ld, max: %d)\n",
192 kernel_size - setup_size, BZIMAGE_MAX_SIZE);
193 return 0;
194 }
wdenk8bde7f72003-06-27 21:31:46 +0000195
wdenk2262cfe2002-11-18 00:14:45 +0000196 } else if ((kernel_size - setup_size) > ZIMAGE_MAX_SIZE) {
197 printf("Error: zImage kernel too big! (size: %ld, max: %d)\n",
198 kernel_size - setup_size, ZIMAGE_MAX_SIZE);
199 return 0;
200 }
wdenk8bde7f72003-06-27 21:31:46 +0000201
wdenk2262cfe2002-11-18 00:14:45 +0000202 /* build command line at COMMAND_LINE_OFFSET */
203 build_command_line(setup_base + COMMAND_LINE_OFFSET, auto_boot);
wdenk8bde7f72003-06-27 21:31:46 +0000204
205 printf("Loading %czImage at address 0x%08x (%ld bytes)\n", big_image ? 'b' : ' ',
wdenk2262cfe2002-11-18 00:14:45 +0000206 (u32)load_address, kernel_size - setup_size);
207
wdenk8bde7f72003-06-27 21:31:46 +0000208
wdenk2262cfe2002-11-18 00:14:45 +0000209 memmove(load_address, image + setup_size, kernel_size - setup_size);
wdenk8bde7f72003-06-27 21:31:46 +0000210
wdenk2262cfe2002-11-18 00:14:45 +0000211 /* ready for booting */
212 return setup_base;
213}
214
wdenk2262cfe2002-11-18 00:14:45 +0000215void boot_zimage(void *setup_base)
216{
217 struct pt_regs regs;
wdenk8bde7f72003-06-27 21:31:46 +0000218
wdenk2262cfe2002-11-18 00:14:45 +0000219 memset(&regs, 0, sizeof(struct pt_regs));
220 regs.xds = (u32)setup_base >> 4;
wdenk7a8e9bed2003-05-31 18:35:21 +0000221 regs.xss = 0x9000;
222 regs.esp = 0x9000;
wdenk2262cfe2002-11-18 00:14:45 +0000223 regs.eflags = 0;
224 enter_realmode(((u32)setup_base+SETUP_START_OFFSET)>>4, 0, &regs, &regs);
225}