xref: /openbmc/u-boot/arch/x86/lib/zimage.c (revision 32c81ea6)
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 				ulong *load_addressp)
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 = &params->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_addressp = BZIMAGE_LOAD_ADDR;
159 	else
160 		*load_addressp = 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 %lx (%ld bytes)\n",
208 	       big_image ? "bzImage" : "zImage", *load_addressp, kernel_size);
209 
210 	memmove((void *)*load_addressp, 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 setup_pcat_compatibility(void)
265 	__attribute__((weak, alias("__setup_pcat_compatibility")));
266 
267 void __setup_pcat_compatibility(void)
268 {
269 }
270 
271 int do_zboot(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
272 {
273 	struct boot_params *base_ptr;
274 	void *bzImage_addr = NULL;
275 	ulong load_address;
276 	char *s;
277 	ulong bzImage_size = 0;
278 	ulong initrd_addr = 0;
279 	ulong initrd_size = 0;
280 
281 	disable_interrupts();
282 
283 	/* Setup board for maximum PC/AT Compatibility */
284 	setup_pcat_compatibility();
285 
286 	if (argc >= 2) {
287 		/* argv[1] holds the address of the bzImage */
288 		s = argv[1];
289 	} else {
290 		s = getenv("fileaddr");
291 	}
292 
293 	if (s)
294 		bzImage_addr = (void *)simple_strtoul(s, NULL, 16);
295 
296 	if (argc >= 3) {
297 		/* argv[2] holds the size of the bzImage */
298 		bzImage_size = simple_strtoul(argv[2], NULL, 16);
299 	}
300 
301 	if (argc >= 4)
302 		initrd_addr = simple_strtoul(argv[3], NULL, 16);
303 	if (argc >= 5)
304 		initrd_size = simple_strtoul(argv[4], NULL, 16);
305 
306 	/* Lets look for */
307 	base_ptr = load_zimage(bzImage_addr, bzImage_size, &load_address);
308 
309 	if (!base_ptr) {
310 		puts("## Kernel loading failed ...\n");
311 		return -1;
312 	}
313 	if (setup_zimage(base_ptr, (char *)base_ptr + COMMAND_LINE_OFFSET,
314 			0, initrd_addr, initrd_size)) {
315 		puts("Setting up boot parameters failed ...\n");
316 		return -1;
317 	}
318 
319 	/* we assume that the kernel is in place */
320 	return boot_linux_kernel((ulong)base_ptr, load_address, false);
321 }
322 
323 U_BOOT_CMD(
324 	zboot, 5, 0,	do_zboot,
325 	"Boot bzImage",
326 	"[addr] [size] [initrd addr] [initrd size]\n"
327 	"      addr -        The optional starting address of the bzimage.\n"
328 	"                    If not set it defaults to the environment\n"
329 	"                    variable \"fileaddr\".\n"
330 	"      size -        The optional size of the bzimage. Defaults to\n"
331 	"                    zero.\n"
332 	"      initrd addr - The address of the initrd image to use, if any.\n"
333 	"      initrd size - The size of the initrd image to use, if any.\n"
334 );
335