1 /* 2 * Copyright (c) 2011 The Chromium OS Authors. 3 * (C) Copyright 2002 4 * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se> 5 * 6 * SPDX-License-Identifier: GPL-2.0+ 7 */ 8 9 /* 10 * Linux x86 zImage and bzImage loading 11 * 12 * based on the procdure described in 13 * linux/Documentation/i386/boot.txt 14 */ 15 16 #include <common.h> 17 #include <asm/io.h> 18 #include <asm/ptrace.h> 19 #include <asm/zimage.h> 20 #include <asm/byteorder.h> 21 #include <asm/bootm.h> 22 #include <asm/bootparam.h> 23 #ifdef CONFIG_SYS_COREBOOT 24 #include <asm/arch/timestamp.h> 25 #endif 26 #include <linux/compiler.h> 27 28 /* 29 * Memory lay-out: 30 * 31 * relative to setup_base (which is 0x90000 currently) 32 * 33 * 0x0000-0x7FFF Real mode kernel 34 * 0x8000-0x8FFF Stack and heap 35 * 0x9000-0x90FF Kernel command line 36 */ 37 #define DEFAULT_SETUP_BASE 0x90000 38 #define COMMAND_LINE_OFFSET 0x9000 39 #define HEAP_END_OFFSET 0x8e00 40 41 #define COMMAND_LINE_SIZE 2048 42 43 unsigned generic_install_e820_map(unsigned max_entries, 44 struct e820entry *entries) 45 { 46 return 0; 47 } 48 49 unsigned install_e820_map(unsigned max_entries, 50 struct e820entry *entries) 51 __attribute__((weak, alias("generic_install_e820_map"))); 52 53 static void build_command_line(char *command_line, int auto_boot) 54 { 55 char *env_command_line; 56 57 command_line[0] = '\0'; 58 59 env_command_line = getenv("bootargs"); 60 61 /* set console= argument if we use a serial console */ 62 if (!strstr(env_command_line, "console=")) { 63 if (!strcmp(getenv("stdout"), "serial")) { 64 65 /* We seem to use serial console */ 66 sprintf(command_line, "console=ttyS0,%s ", 67 getenv("baudrate")); 68 } 69 } 70 71 if (auto_boot) 72 strcat(command_line, "auto "); 73 74 if (env_command_line) 75 strcat(command_line, env_command_line); 76 77 printf("Kernel command line: \"%s\"\n", command_line); 78 } 79 80 static int kernel_magic_ok(struct setup_header *hdr) 81 { 82 if (KERNEL_MAGIC != hdr->boot_flag) { 83 printf("Error: Invalid Boot Flag " 84 "(found 0x%04x, expected 0x%04x)\n", 85 hdr->boot_flag, KERNEL_MAGIC); 86 return 0; 87 } else { 88 printf("Valid Boot Flag\n"); 89 return 1; 90 } 91 } 92 93 static int get_boot_protocol(struct setup_header *hdr) 94 { 95 if (hdr->header == KERNEL_V2_MAGIC) { 96 printf("Magic signature found\n"); 97 return hdr->version; 98 } else { 99 /* Very old kernel */ 100 printf("Magic signature not found\n"); 101 return 0x0100; 102 } 103 } 104 105 struct boot_params *load_zimage(char *image, unsigned long kernel_size, 106 void **load_address) 107 { 108 struct boot_params *setup_base; 109 int setup_size; 110 int bootproto; 111 int big_image; 112 113 struct boot_params *params = (struct boot_params *)image; 114 struct setup_header *hdr = ¶ms->hdr; 115 116 /* base address for real-mode segment */ 117 setup_base = (struct boot_params *)DEFAULT_SETUP_BASE; 118 119 if (!kernel_magic_ok(hdr)) 120 return 0; 121 122 /* determine size of setup */ 123 if (0 == hdr->setup_sects) { 124 printf("Setup Sectors = 0 (defaulting to 4)\n"); 125 setup_size = 5 * 512; 126 } else { 127 setup_size = (hdr->setup_sects + 1) * 512; 128 } 129 130 printf("Setup Size = 0x%8.8lx\n", (ulong)setup_size); 131 132 if (setup_size > SETUP_MAX_SIZE) 133 printf("Error: Setup is too large (%d bytes)\n", setup_size); 134 135 /* determine boot protocol version */ 136 bootproto = get_boot_protocol(hdr); 137 138 printf("Using boot protocol version %x.%02x\n", 139 (bootproto & 0xff00) >> 8, bootproto & 0xff); 140 141 if (bootproto >= 0x0200) { 142 if (hdr->setup_sects >= 15) { 143 printf("Linux kernel version %s\n", 144 (char *)params + 145 hdr->kernel_version + 0x200); 146 } else { 147 printf("Setup Sectors < 15 - " 148 "Cannot print kernel version.\n"); 149 } 150 } 151 152 /* Determine image type */ 153 big_image = (bootproto >= 0x0200) && 154 (hdr->loadflags & BIG_KERNEL_FLAG); 155 156 /* Determine load address */ 157 if (big_image) 158 *load_address = (void *)BZIMAGE_LOAD_ADDR; 159 else 160 *load_address = (void *)ZIMAGE_LOAD_ADDR; 161 162 printf("Building boot_params at 0x%8.8lx\n", (ulong)setup_base); 163 memset(setup_base, 0, sizeof(*setup_base)); 164 setup_base->hdr = params->hdr; 165 166 if (bootproto >= 0x0204) 167 kernel_size = hdr->syssize * 16; 168 else 169 kernel_size -= setup_size; 170 171 if (bootproto == 0x0100) { 172 /* 173 * A very old kernel MUST have its real-mode code 174 * loaded at 0x90000 175 */ 176 if ((u32)setup_base != 0x90000) { 177 /* Copy the real-mode kernel */ 178 memmove((void *)0x90000, setup_base, setup_size); 179 180 /* Copy the command line */ 181 memmove((void *)0x99000, 182 (u8 *)setup_base + COMMAND_LINE_OFFSET, 183 COMMAND_LINE_SIZE); 184 185 /* Relocated */ 186 setup_base = (struct boot_params *)0x90000; 187 } 188 189 /* It is recommended to clear memory up to the 32K mark */ 190 memset((u8 *)0x90000 + setup_size, 0, 191 SETUP_MAX_SIZE - setup_size); 192 } 193 194 if (big_image) { 195 if (kernel_size > BZIMAGE_MAX_SIZE) { 196 printf("Error: bzImage kernel too big! " 197 "(size: %ld, max: %d)\n", 198 kernel_size, BZIMAGE_MAX_SIZE); 199 return 0; 200 } 201 } else if ((kernel_size) > ZIMAGE_MAX_SIZE) { 202 printf("Error: zImage kernel too big! (size: %ld, max: %d)\n", 203 kernel_size, ZIMAGE_MAX_SIZE); 204 return 0; 205 } 206 207 printf("Loading %s at address %p (%ld bytes)\n", 208 big_image ? "bzImage" : "zImage", *load_address, kernel_size); 209 210 memmove(*load_address, image + setup_size, kernel_size); 211 212 return setup_base; 213 } 214 215 int setup_zimage(struct boot_params *setup_base, char *cmd_line, int auto_boot, 216 unsigned long initrd_addr, unsigned long initrd_size) 217 { 218 struct setup_header *hdr = &setup_base->hdr; 219 int bootproto = get_boot_protocol(hdr); 220 221 setup_base->e820_entries = install_e820_map( 222 ARRAY_SIZE(setup_base->e820_map), setup_base->e820_map); 223 224 if (bootproto == 0x0100) { 225 setup_base->screen_info.cl_magic = COMMAND_LINE_MAGIC; 226 setup_base->screen_info.cl_offset = COMMAND_LINE_OFFSET; 227 } 228 if (bootproto >= 0x0200) { 229 hdr->type_of_loader = 8; 230 231 if (initrd_addr) { 232 printf("Initial RAM disk at linear address " 233 "0x%08lx, size %ld bytes\n", 234 initrd_addr, initrd_size); 235 236 hdr->ramdisk_image = initrd_addr; 237 hdr->ramdisk_size = initrd_size; 238 } 239 } 240 241 if (bootproto >= 0x0201) { 242 hdr->heap_end_ptr = HEAP_END_OFFSET; 243 hdr->loadflags |= HEAP_FLAG; 244 } 245 246 if (cmd_line) { 247 if (bootproto >= 0x0202) { 248 hdr->cmd_line_ptr = (uintptr_t)cmd_line; 249 } else if (bootproto >= 0x0200) { 250 setup_base->screen_info.cl_magic = COMMAND_LINE_MAGIC; 251 setup_base->screen_info.cl_offset = 252 (uintptr_t)cmd_line - (uintptr_t)setup_base; 253 254 hdr->setup_move_size = 0x9100; 255 } 256 257 /* build command line at COMMAND_LINE_OFFSET */ 258 build_command_line(cmd_line, auto_boot); 259 } 260 261 return 0; 262 } 263 264 void boot_zimage(void *setup_base, void *load_address) 265 { 266 bootm_announce_and_cleanup(); 267 268 #ifdef CONFIG_SYS_COREBOOT 269 timestamp_add_now(TS_U_BOOT_START_KERNEL); 270 #endif 271 /* 272 * Set %ebx, %ebp, and %edi to 0, %esi to point to the boot_params 273 * structure, and then jump to the kernel. We assume that %cs is 274 * 0x10, 4GB flat, and read/execute, and the data segments are 0x18, 275 * 4GB flat, and read/write. U-boot is setting them up that way for 276 * itself in arch/i386/cpu/cpu.c. 277 */ 278 __asm__ __volatile__ ( 279 "movl $0, %%ebp\n" 280 "cli\n" 281 "jmp *%[kernel_entry]\n" 282 :: [kernel_entry]"a"(load_address), 283 [boot_params] "S"(setup_base), 284 "b"(0), "D"(0) 285 ); 286 } 287 288 void setup_pcat_compatibility(void) 289 __attribute__((weak, alias("__setup_pcat_compatibility"))); 290 291 void __setup_pcat_compatibility(void) 292 { 293 } 294 295 int do_zboot(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[]) 296 { 297 struct boot_params *base_ptr; 298 void *bzImage_addr = NULL; 299 void *load_address; 300 char *s; 301 ulong bzImage_size = 0; 302 ulong initrd_addr = 0; 303 ulong initrd_size = 0; 304 305 disable_interrupts(); 306 307 /* Setup board for maximum PC/AT Compatibility */ 308 setup_pcat_compatibility(); 309 310 if (argc >= 2) { 311 /* argv[1] holds the address of the bzImage */ 312 s = argv[1]; 313 } else { 314 s = getenv("fileaddr"); 315 } 316 317 if (s) 318 bzImage_addr = (void *)simple_strtoul(s, NULL, 16); 319 320 if (argc >= 3) { 321 /* argv[2] holds the size of the bzImage */ 322 bzImage_size = simple_strtoul(argv[2], NULL, 16); 323 } 324 325 if (argc >= 4) 326 initrd_addr = simple_strtoul(argv[3], NULL, 16); 327 if (argc >= 5) 328 initrd_size = simple_strtoul(argv[4], NULL, 16); 329 330 /* Lets look for */ 331 base_ptr = load_zimage(bzImage_addr, bzImage_size, &load_address); 332 333 if (!base_ptr) { 334 printf("## Kernel loading failed ...\n"); 335 return -1; 336 } 337 if (setup_zimage(base_ptr, (char *)base_ptr + COMMAND_LINE_OFFSET, 338 0, initrd_addr, initrd_size)) { 339 printf("Setting up boot parameters failed ...\n"); 340 return -1; 341 } 342 343 /* we assume that the kernel is in place */ 344 boot_zimage(base_ptr, load_address); 345 /* does not return */ 346 347 return -1; 348 } 349 350 U_BOOT_CMD( 351 zboot, 5, 0, do_zboot, 352 "Boot bzImage", 353 "[addr] [size] [initrd addr] [initrd size]\n" 354 " addr - The optional starting address of the bzimage.\n" 355 " If not set it defaults to the environment\n" 356 " variable \"fileaddr\".\n" 357 " size - The optional size of the bzimage. Defaults to\n" 358 " zero.\n" 359 " initrd addr - The address of the initrd image to use, if any.\n" 360 " initrd size - The size of the initrd image to use, if any.\n" 361 ); 362