2 * Copyright (c) 2011 The Chromium OS Authors.
4 * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
6 * See file CREDITS for list of people who contributed to this
9 * This program is free software; you can redistribute it and/or
10 * modify it under the terms of the GNU General Public License as
11 * published by the Free Software Foundation; either version 2 of
12 * the License, or (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
26 * Linux x86 zImage and bzImage loading
28 * based on the procdure described in
29 * linux/Documentation/i386/boot.txt
34 #include <asm/ptrace.h>
35 #include <asm/zimage.h>
36 #include <asm/realmode.h>
37 #include <asm/byteorder.h>
38 #include <asm/bootparam.h>
39 #ifdef CONFIG_SYS_COREBOOT
40 #include <asm/arch/timestamp.h>
46 * relative to setup_base (which is 0x90000 currently)
48 * 0x0000-0x7FFF Real mode kernel
49 * 0x8000-0x8FFF Stack and heap
50 * 0x9000-0x90FF Kernel command line
52 #define DEFAULT_SETUP_BASE 0x90000
53 #define COMMAND_LINE_OFFSET 0x9000
54 #define HEAP_END_OFFSET 0x8e00
56 #define COMMAND_LINE_SIZE 2048
58 unsigned generic_install_e820_map(unsigned max_entries,
59 struct e820entry *entries)
64 unsigned install_e820_map(unsigned max_entries,
65 struct e820entry *entries)
66 __attribute__((weak, alias("generic_install_e820_map")));
68 static void build_command_line(char *command_line, int auto_boot)
70 char *env_command_line;
72 command_line[0] = '\0';
74 env_command_line = getenv("bootargs");
76 /* set console= argument if we use a serial console */
77 if (!strstr(env_command_line, "console=")) {
78 if (!strcmp(getenv("stdout"), "serial")) {
80 /* We seem to use serial console */
81 sprintf(command_line, "console=ttyS0,%s ",
87 strcat(command_line, "auto ");
90 strcat(command_line, env_command_line);
92 printf("Kernel command line: \"%s\"\n", command_line);
95 static int kernel_magic_ok(struct setup_header *hdr)
97 if (KERNEL_MAGIC != hdr->boot_flag) {
98 printf("Error: Invalid Boot Flag "
99 "(found 0x%04x, expected 0x%04x)\n",
100 hdr->boot_flag, KERNEL_MAGIC);
103 printf("Valid Boot Flag\n");
108 static int get_boot_protocol(struct setup_header *hdr)
110 if (hdr->header == KERNEL_V2_MAGIC) {
111 printf("Magic signature found\n");
114 /* Very old kernel */
115 printf("Magic signature not found\n");
120 struct boot_params *load_zimage(char *image, unsigned long kernel_size,
123 struct boot_params *setup_base;
128 struct boot_params *params = (struct boot_params *)image;
129 struct setup_header *hdr = ¶ms->hdr;
131 /* base address for real-mode segment */
132 setup_base = (struct boot_params *)DEFAULT_SETUP_BASE;
134 if (!kernel_magic_ok(hdr))
137 /* determine size of setup */
138 if (0 == hdr->setup_sects) {
139 printf("Setup Sectors = 0 (defaulting to 4)\n");
140 setup_size = 5 * 512;
142 setup_size = (hdr->setup_sects + 1) * 512;
145 printf("Setup Size = 0x%8.8lx\n", (ulong)setup_size);
147 if (setup_size > SETUP_MAX_SIZE)
148 printf("Error: Setup is too large (%d bytes)\n", setup_size);
150 /* determine boot protocol version */
151 bootproto = get_boot_protocol(hdr);
153 printf("Using boot protocol version %x.%02x\n",
154 (bootproto & 0xff00) >> 8, bootproto & 0xff);
156 if (bootproto >= 0x0200) {
157 if (hdr->setup_sects >= 15) {
158 printf("Linux kernel version %s\n",
160 hdr->kernel_version + 0x200);
162 printf("Setup Sectors < 15 - "
163 "Cannot print kernel version.\n");
167 /* Determine image type */
168 big_image = (bootproto >= 0x0200) &&
169 (hdr->loadflags & BIG_KERNEL_FLAG);
171 /* Determine load address */
173 *load_address = (void *)BZIMAGE_LOAD_ADDR;
175 *load_address = (void *)ZIMAGE_LOAD_ADDR;
177 #if (defined CONFIG_ZBOOT_32 || defined CONFIG_X86_NO_REAL_MODE)
178 printf("Building boot_params at 0x%8.8lx\n", (ulong)setup_base);
179 memset(setup_base, 0, sizeof(*setup_base));
180 setup_base->hdr = params->hdr;
183 printf("Moving Real-Mode Code to 0x%8.8lx (%d bytes)\n",
184 (ulong)setup_base, setup_size);
185 memmove(setup_base, image, setup_size);
188 if (bootproto >= 0x0204)
189 kernel_size = hdr->syssize * 16;
191 kernel_size -= setup_size;
193 if (bootproto == 0x0100) {
195 * A very old kernel MUST have its real-mode code
198 if ((u32)setup_base != 0x90000) {
199 /* Copy the real-mode kernel */
200 memmove((void *)0x90000, setup_base, setup_size);
202 /* Copy the command line */
203 memmove((void *)0x99000,
204 (u8 *)setup_base + COMMAND_LINE_OFFSET,
208 setup_base = (struct boot_params *)0x90000;
211 /* It is recommended to clear memory up to the 32K mark */
212 memset((u8 *)0x90000 + setup_size, 0,
213 SETUP_MAX_SIZE - setup_size);
217 if (kernel_size > BZIMAGE_MAX_SIZE) {
218 printf("Error: bzImage kernel too big! "
219 "(size: %ld, max: %d)\n",
220 kernel_size, BZIMAGE_MAX_SIZE);
223 } else if ((kernel_size) > ZIMAGE_MAX_SIZE) {
224 printf("Error: zImage kernel too big! (size: %ld, max: %d)\n",
225 kernel_size, ZIMAGE_MAX_SIZE);
229 printf("Loading %s at address %p (%ld bytes)\n",
230 big_image ? "bzImage" : "zImage", *load_address, kernel_size);
232 memmove(*load_address, image + setup_size, kernel_size);
237 int setup_zimage(struct boot_params *setup_base, char *cmd_line, int auto_boot,
238 unsigned long initrd_addr, unsigned long initrd_size)
240 struct setup_header *hdr = &setup_base->hdr;
241 int bootproto = get_boot_protocol(hdr);
243 #if (defined CONFIG_ZBOOT_32 || defined CONFIG_X86_NO_REAL_MODE)
244 setup_base->e820_entries = install_e820_map(
245 ARRAY_SIZE(setup_base->e820_map), setup_base->e820_map);
248 if (bootproto == 0x0100) {
249 setup_base->screen_info.cl_magic = COMMAND_LINE_MAGIC;
250 setup_base->screen_info.cl_offset = COMMAND_LINE_OFFSET;
252 if (bootproto >= 0x0200) {
253 hdr->type_of_loader = 8;
256 printf("Initial RAM disk at linear address "
257 "0x%08lx, size %ld bytes\n",
258 initrd_addr, initrd_size);
260 hdr->ramdisk_image = initrd_addr;
261 hdr->ramdisk_size = initrd_size;
265 if (bootproto >= 0x0201) {
266 hdr->heap_end_ptr = HEAP_END_OFFSET;
267 hdr->loadflags |= HEAP_FLAG;
270 if (bootproto >= 0x0202) {
271 hdr->cmd_line_ptr = (uintptr_t)cmd_line;
272 } else if (bootproto >= 0x0200) {
273 setup_base->screen_info.cl_magic = COMMAND_LINE_MAGIC;
274 setup_base->screen_info.cl_offset =
275 (uintptr_t)cmd_line - (uintptr_t)setup_base;
277 hdr->setup_move_size = 0x9100;
280 /* build command line at COMMAND_LINE_OFFSET */
281 build_command_line(cmd_line, auto_boot);
285 void boot_zimage(void *setup_base, void *load_address)
287 printf("\nStarting kernel ...\n\n");
289 #ifdef CONFIG_SYS_COREBOOT
290 timestamp_add_now(TS_U_BOOT_START_KERNEL);
292 #if defined CONFIG_ZBOOT_32
294 * Set %ebx, %ebp, and %edi to 0, %esi to point to the boot_params
295 * structure, and then jump to the kernel. We assume that %cs is
296 * 0x10, 4GB flat, and read/execute, and the data segments are 0x18,
297 * 4GB flat, and read/write. U-boot is setting them up that way for
298 * itself in arch/i386/cpu/cpu.c.
300 __asm__ __volatile__ (
303 "jmp %[kernel_entry] \n"
304 :: [kernel_entry]"a"(load_address),
305 [boot_params] "S"(setup_base),
312 memset(®s, 0, sizeof(struct pt_regs));
313 regs.xds = (u32)setup_base >> 4;
318 enter_realmode(((u32)setup_base + SETUP_START_OFFSET) >> 4, 0,
323 void setup_pcat_compatibility(void)
324 __attribute__((weak, alias("__setup_pcat_compatibility")));
326 void __setup_pcat_compatibility(void)
330 int do_zboot(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
332 struct boot_params *base_ptr;
333 void *bzImage_addr = NULL;
336 ulong bzImage_size = 0;
337 ulong initrd_addr = 0;
338 ulong initrd_size = 0;
340 disable_interrupts();
342 /* Setup board for maximum PC/AT Compatibility */
343 setup_pcat_compatibility();
346 /* argv[1] holds the address of the bzImage */
349 s = getenv("fileaddr");
353 bzImage_addr = (void *)simple_strtoul(s, NULL, 16);
356 /* argv[2] holds the size of the bzImage */
357 bzImage_size = simple_strtoul(argv[2], NULL, 16);
361 initrd_addr = simple_strtoul(argv[3], NULL, 16);
363 initrd_size = simple_strtoul(argv[4], NULL, 16);
366 base_ptr = load_zimage(bzImage_addr, bzImage_size, &load_address);
369 printf("## Kernel loading failed ...\n");
372 if (setup_zimage(base_ptr, (char *)base_ptr + COMMAND_LINE_OFFSET,
373 0, initrd_addr, initrd_size)) {
374 printf("Setting up boot parameters failed ...\n");
378 printf("## Transferring control to Linux "
379 "(at address %08x) ...\n",
382 /* we assume that the kernel is in place */
383 boot_zimage(base_ptr, load_address);
384 /* does not return */
390 zboot, 5, 0, do_zboot,
392 "[addr] [size] [initrd addr] [initrd size]\n"
393 " addr - The optional starting address of the bzimage.\n"
394 " If not set it defaults to the environment\n"
395 " variable \"fileaddr\".\n"
396 " size - The optional size of the bzimage. Defaults to\n"
398 " initrd addr - The address of the initrd image to use, if any.\n"
399 " initrd size - The size of the initrd image to use, if any.\n"