2 * Copyright (c) 2011 The Chromium OS Authors.
4 * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
6 * SPDX-License-Identifier: GPL-2.0+
10 * Linux x86 zImage and bzImage loading
12 * based on the procdure described in
13 * linux/Documentation/i386/boot.txt
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>
26 #include <linux/compiler.h>
31 * relative to setup_base (which is 0x90000 currently)
33 * 0x0000-0x7FFF Real mode kernel
34 * 0x8000-0x8FFF Stack and heap
35 * 0x9000-0x90FF Kernel command line
37 #define DEFAULT_SETUP_BASE 0x90000
38 #define COMMAND_LINE_OFFSET 0x9000
39 #define HEAP_END_OFFSET 0x8e00
41 #define COMMAND_LINE_SIZE 2048
43 unsigned generic_install_e820_map(unsigned max_entries,
44 struct e820entry *entries)
49 unsigned install_e820_map(unsigned max_entries,
50 struct e820entry *entries)
51 __attribute__((weak, alias("generic_install_e820_map")));
53 static void build_command_line(char *command_line, int auto_boot)
55 char *env_command_line;
57 command_line[0] = '\0';
59 env_command_line = getenv("bootargs");
61 /* set console= argument if we use a serial console */
62 if (!strstr(env_command_line, "console=")) {
63 if (!strcmp(getenv("stdout"), "serial")) {
65 /* We seem to use serial console */
66 sprintf(command_line, "console=ttyS0,%s ",
72 strcat(command_line, "auto ");
75 strcat(command_line, env_command_line);
77 printf("Kernel command line: \"%s\"\n", command_line);
80 static int kernel_magic_ok(struct setup_header *hdr)
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);
88 printf("Valid Boot Flag\n");
93 static int get_boot_protocol(struct setup_header *hdr)
95 if (hdr->header == KERNEL_V2_MAGIC) {
96 printf("Magic signature found\n");
100 printf("Magic signature not found\n");
105 struct boot_params *load_zimage(char *image, unsigned long kernel_size,
108 struct boot_params *setup_base;
113 struct boot_params *params = (struct boot_params *)image;
114 struct setup_header *hdr = ¶ms->hdr;
116 /* base address for real-mode segment */
117 setup_base = (struct boot_params *)DEFAULT_SETUP_BASE;
119 if (!kernel_magic_ok(hdr))
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;
127 setup_size = (hdr->setup_sects + 1) * 512;
130 printf("Setup Size = 0x%8.8lx\n", (ulong)setup_size);
132 if (setup_size > SETUP_MAX_SIZE)
133 printf("Error: Setup is too large (%d bytes)\n", setup_size);
135 /* determine boot protocol version */
136 bootproto = get_boot_protocol(hdr);
138 printf("Using boot protocol version %x.%02x\n",
139 (bootproto & 0xff00) >> 8, bootproto & 0xff);
141 if (bootproto >= 0x0200) {
142 if (hdr->setup_sects >= 15) {
143 printf("Linux kernel version %s\n",
145 hdr->kernel_version + 0x200);
147 printf("Setup Sectors < 15 - "
148 "Cannot print kernel version.\n");
152 /* Determine image type */
153 big_image = (bootproto >= 0x0200) &&
154 (hdr->loadflags & BIG_KERNEL_FLAG);
156 /* Determine load address */
158 *load_address = (void *)BZIMAGE_LOAD_ADDR;
160 *load_address = (void *)ZIMAGE_LOAD_ADDR;
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;
166 if (bootproto >= 0x0204)
167 kernel_size = hdr->syssize * 16;
169 kernel_size -= setup_size;
171 if (bootproto == 0x0100) {
173 * A very old kernel MUST have its real-mode code
176 if ((u32)setup_base != 0x90000) {
177 /* Copy the real-mode kernel */
178 memmove((void *)0x90000, setup_base, setup_size);
180 /* Copy the command line */
181 memmove((void *)0x99000,
182 (u8 *)setup_base + COMMAND_LINE_OFFSET,
186 setup_base = (struct boot_params *)0x90000;
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);
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);
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);
207 printf("Loading %s at address %p (%ld bytes)\n",
208 big_image ? "bzImage" : "zImage", *load_address, kernel_size);
210 memmove(*load_address, image + setup_size, kernel_size);
215 int setup_zimage(struct boot_params *setup_base, char *cmd_line, int auto_boot,
216 unsigned long initrd_addr, unsigned long initrd_size)
218 struct setup_header *hdr = &setup_base->hdr;
219 int bootproto = get_boot_protocol(hdr);
221 setup_base->e820_entries = install_e820_map(
222 ARRAY_SIZE(setup_base->e820_map), setup_base->e820_map);
224 if (bootproto == 0x0100) {
225 setup_base->screen_info.cl_magic = COMMAND_LINE_MAGIC;
226 setup_base->screen_info.cl_offset = COMMAND_LINE_OFFSET;
228 if (bootproto >= 0x0200) {
229 hdr->type_of_loader = 8;
232 printf("Initial RAM disk at linear address "
233 "0x%08lx, size %ld bytes\n",
234 initrd_addr, initrd_size);
236 hdr->ramdisk_image = initrd_addr;
237 hdr->ramdisk_size = initrd_size;
241 if (bootproto >= 0x0201) {
242 hdr->heap_end_ptr = HEAP_END_OFFSET;
243 hdr->loadflags |= HEAP_FLAG;
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;
254 hdr->setup_move_size = 0x9100;
257 /* build command line at COMMAND_LINE_OFFSET */
258 build_command_line(cmd_line, auto_boot);
264 void boot_zimage(void *setup_base, void *load_address)
266 bootm_announce_and_cleanup();
268 #ifdef CONFIG_SYS_COREBOOT
269 timestamp_add_now(TS_U_BOOT_START_KERNEL);
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.
278 __asm__ __volatile__ (
281 "jmp *%[kernel_entry]\n"
282 :: [kernel_entry]"a"(load_address),
283 [boot_params] "S"(setup_base),
288 void setup_pcat_compatibility(void)
289 __attribute__((weak, alias("__setup_pcat_compatibility")));
291 void __setup_pcat_compatibility(void)
295 int do_zboot(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
297 struct boot_params *base_ptr;
298 void *bzImage_addr = NULL;
301 ulong bzImage_size = 0;
302 ulong initrd_addr = 0;
303 ulong initrd_size = 0;
305 disable_interrupts();
307 /* Setup board for maximum PC/AT Compatibility */
308 setup_pcat_compatibility();
311 /* argv[1] holds the address of the bzImage */
314 s = getenv("fileaddr");
318 bzImage_addr = (void *)simple_strtoul(s, NULL, 16);
321 /* argv[2] holds the size of the bzImage */
322 bzImage_size = simple_strtoul(argv[2], NULL, 16);
326 initrd_addr = simple_strtoul(argv[3], NULL, 16);
328 initrd_size = simple_strtoul(argv[4], NULL, 16);
331 base_ptr = load_zimage(bzImage_addr, bzImage_size, &load_address);
334 printf("## Kernel loading failed ...\n");
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");
343 /* we assume that the kernel is in place */
344 boot_zimage(base_ptr, load_address);
345 /* does not return */
351 zboot, 5, 0, do_zboot,
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"
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"