xref: /openbmc/u-boot/arch/x86/lib/zimage.c (revision 0093b3fc)
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/acpi_table.h>
18 #include <asm/io.h>
19 #include <asm/ptrace.h>
20 #include <asm/zimage.h>
21 #include <asm/byteorder.h>
22 #include <asm/bootm.h>
23 #include <asm/bootparam.h>
24 #ifdef CONFIG_SYS_COREBOOT
25 #include <asm/arch/timestamp.h>
26 #endif
27 #include <linux/compiler.h>
28 
29 DECLARE_GLOBAL_DATA_PTR;
30 
31 /*
32  * Memory lay-out:
33  *
34  * relative to setup_base (which is 0x90000 currently)
35  *
36  *	0x0000-0x7FFF	Real mode kernel
37  *	0x8000-0x8FFF	Stack and heap
38  *	0x9000-0x90FF	Kernel command line
39  */
40 #define DEFAULT_SETUP_BASE	0x90000
41 #define COMMAND_LINE_OFFSET	0x9000
42 #define HEAP_END_OFFSET		0x8e00
43 
44 #define COMMAND_LINE_SIZE	2048
45 
46 static void build_command_line(char *command_line, int auto_boot)
47 {
48 	char *env_command_line;
49 
50 	command_line[0] = '\0';
51 
52 	env_command_line =  env_get("bootargs");
53 
54 	/* set console= argument if we use a serial console */
55 	if (!strstr(env_command_line, "console=")) {
56 		if (!strcmp(env_get("stdout"), "serial")) {
57 
58 			/* We seem to use serial console */
59 			sprintf(command_line, "console=ttyS0,%s ",
60 				env_get("baudrate"));
61 		}
62 	}
63 
64 	if (auto_boot)
65 		strcat(command_line, "auto ");
66 
67 	if (env_command_line)
68 		strcat(command_line, env_command_line);
69 
70 	printf("Kernel command line: \"%s\"\n", command_line);
71 }
72 
73 static int kernel_magic_ok(struct setup_header *hdr)
74 {
75 	if (KERNEL_MAGIC != hdr->boot_flag) {
76 		printf("Error: Invalid Boot Flag "
77 			"(found 0x%04x, expected 0x%04x)\n",
78 			hdr->boot_flag, KERNEL_MAGIC);
79 		return 0;
80 	} else {
81 		printf("Valid Boot Flag\n");
82 		return 1;
83 	}
84 }
85 
86 static int get_boot_protocol(struct setup_header *hdr)
87 {
88 	if (hdr->header == KERNEL_V2_MAGIC) {
89 		printf("Magic signature found\n");
90 		return hdr->version;
91 	} else {
92 		/* Very old kernel */
93 		printf("Magic signature not found\n");
94 		return 0x0100;
95 	}
96 }
97 
98 struct boot_params *load_zimage(char *image, unsigned long kernel_size,
99 				ulong *load_addressp)
100 {
101 	struct boot_params *setup_base;
102 	int setup_size;
103 	int bootproto;
104 	int big_image;
105 
106 	struct boot_params *params = (struct boot_params *)image;
107 	struct setup_header *hdr = &params->hdr;
108 
109 	/* base address for real-mode segment */
110 	setup_base = (struct boot_params *)DEFAULT_SETUP_BASE;
111 
112 	if (!kernel_magic_ok(hdr))
113 		return 0;
114 
115 	/* determine size of setup */
116 	if (0 == hdr->setup_sects) {
117 		printf("Setup Sectors = 0 (defaulting to 4)\n");
118 		setup_size = 5 * 512;
119 	} else {
120 		setup_size = (hdr->setup_sects + 1) * 512;
121 	}
122 
123 	printf("Setup Size = 0x%8.8lx\n", (ulong)setup_size);
124 
125 	if (setup_size > SETUP_MAX_SIZE)
126 		printf("Error: Setup is too large (%d bytes)\n", setup_size);
127 
128 	/* determine boot protocol version */
129 	bootproto = get_boot_protocol(hdr);
130 
131 	printf("Using boot protocol version %x.%02x\n",
132 	       (bootproto & 0xff00) >> 8, bootproto & 0xff);
133 
134 	if (bootproto >= 0x0200) {
135 		if (hdr->setup_sects >= 15) {
136 			printf("Linux kernel version %s\n",
137 				(char *)params +
138 				hdr->kernel_version + 0x200);
139 		} else {
140 			printf("Setup Sectors < 15 - "
141 				"Cannot print kernel version.\n");
142 		}
143 	}
144 
145 	/* Determine image type */
146 	big_image = (bootproto >= 0x0200) &&
147 		    (hdr->loadflags & BIG_KERNEL_FLAG);
148 
149 	/* Determine load address */
150 	if (big_image)
151 		*load_addressp = BZIMAGE_LOAD_ADDR;
152 	else
153 		*load_addressp = ZIMAGE_LOAD_ADDR;
154 
155 	printf("Building boot_params at 0x%8.8lx\n", (ulong)setup_base);
156 	memset(setup_base, 0, sizeof(*setup_base));
157 	setup_base->hdr = params->hdr;
158 
159 	if (bootproto >= 0x0204)
160 		kernel_size = hdr->syssize * 16;
161 	else
162 		kernel_size -= setup_size;
163 
164 	if (bootproto == 0x0100) {
165 		/*
166 		 * A very old kernel MUST have its real-mode code
167 		 * loaded at 0x90000
168 		 */
169 		if ((ulong)setup_base != 0x90000) {
170 			/* Copy the real-mode kernel */
171 			memmove((void *)0x90000, setup_base, setup_size);
172 
173 			/* Copy the command line */
174 			memmove((void *)0x99000,
175 				(u8 *)setup_base + COMMAND_LINE_OFFSET,
176 				COMMAND_LINE_SIZE);
177 
178 			 /* Relocated */
179 			setup_base = (struct boot_params *)0x90000;
180 		}
181 
182 		/* It is recommended to clear memory up to the 32K mark */
183 		memset((u8 *)0x90000 + setup_size, 0,
184 		       SETUP_MAX_SIZE - setup_size);
185 	}
186 
187 	if (big_image) {
188 		if (kernel_size > BZIMAGE_MAX_SIZE) {
189 			printf("Error: bzImage kernel too big! "
190 				"(size: %ld, max: %d)\n",
191 				kernel_size, BZIMAGE_MAX_SIZE);
192 			return 0;
193 		}
194 	} else if ((kernel_size) > ZIMAGE_MAX_SIZE) {
195 		printf("Error: zImage kernel too big! (size: %ld, max: %d)\n",
196 		       kernel_size, ZIMAGE_MAX_SIZE);
197 		return 0;
198 	}
199 
200 	printf("Loading %s at address %lx (%ld bytes)\n",
201 	       big_image ? "bzImage" : "zImage", *load_addressp, kernel_size);
202 
203 	memmove((void *)*load_addressp, image + setup_size, kernel_size);
204 
205 	return setup_base;
206 }
207 
208 int setup_zimage(struct boot_params *setup_base, char *cmd_line, int auto_boot,
209 		 unsigned long initrd_addr, unsigned long initrd_size)
210 {
211 	struct setup_header *hdr = &setup_base->hdr;
212 	int bootproto = get_boot_protocol(hdr);
213 
214 	setup_base->e820_entries = install_e820_map(
215 		ARRAY_SIZE(setup_base->e820_map), setup_base->e820_map);
216 
217 	if (bootproto == 0x0100) {
218 		setup_base->screen_info.cl_magic = COMMAND_LINE_MAGIC;
219 		setup_base->screen_info.cl_offset = COMMAND_LINE_OFFSET;
220 	}
221 	if (bootproto >= 0x0200) {
222 		hdr->type_of_loader = 8;
223 
224 		if (initrd_addr) {
225 			printf("Initial RAM disk at linear address "
226 			       "0x%08lx, size %ld bytes\n",
227 			       initrd_addr, initrd_size);
228 
229 			hdr->ramdisk_image = initrd_addr;
230 			hdr->ramdisk_size = initrd_size;
231 		}
232 	}
233 
234 	if (bootproto >= 0x0201) {
235 		hdr->heap_end_ptr = HEAP_END_OFFSET;
236 		hdr->loadflags |= HEAP_FLAG;
237 	}
238 
239 	if (cmd_line) {
240 		if (bootproto >= 0x0202) {
241 			hdr->cmd_line_ptr = (uintptr_t)cmd_line;
242 		} else if (bootproto >= 0x0200) {
243 			setup_base->screen_info.cl_magic = COMMAND_LINE_MAGIC;
244 			setup_base->screen_info.cl_offset =
245 				(uintptr_t)cmd_line - (uintptr_t)setup_base;
246 
247 			hdr->setup_move_size = 0x9100;
248 		}
249 
250 		/* build command line at COMMAND_LINE_OFFSET */
251 		build_command_line(cmd_line, auto_boot);
252 	}
253 
254 #ifdef CONFIG_INTEL_MID
255 	if (bootproto >= 0x0207)
256 		hdr->hardware_subarch = X86_SUBARCH_INTEL_MID;
257 #endif
258 
259 #ifdef CONFIG_GENERATE_ACPI_TABLE
260 	if (bootproto >= 0x020e)
261 		hdr->acpi_rsdp_addr = acpi_get_rsdp_addr();
262 #endif
263 
264 	setup_video(&setup_base->screen_info);
265 
266 	return 0;
267 }
268 
269 void setup_pcat_compatibility(void)
270 	__attribute__((weak, alias("__setup_pcat_compatibility")));
271 
272 void __setup_pcat_compatibility(void)
273 {
274 }
275 
276 int do_zboot(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
277 {
278 	struct boot_params *base_ptr;
279 	void *bzImage_addr = NULL;
280 	ulong load_address;
281 	char *s;
282 	ulong bzImage_size = 0;
283 	ulong initrd_addr = 0;
284 	ulong initrd_size = 0;
285 
286 	disable_interrupts();
287 
288 	/* Setup board for maximum PC/AT Compatibility */
289 	setup_pcat_compatibility();
290 
291 	if (argc >= 2) {
292 		/* argv[1] holds the address of the bzImage */
293 		s = argv[1];
294 	} else {
295 		s = env_get("fileaddr");
296 	}
297 
298 	if (s)
299 		bzImage_addr = (void *)simple_strtoul(s, NULL, 16);
300 
301 	if (argc >= 3) {
302 		/* argv[2] holds the size of the bzImage */
303 		bzImage_size = simple_strtoul(argv[2], NULL, 16);
304 	}
305 
306 	if (argc >= 4)
307 		initrd_addr = simple_strtoul(argv[3], NULL, 16);
308 	if (argc >= 5)
309 		initrd_size = simple_strtoul(argv[4], NULL, 16);
310 
311 	/* Lets look for */
312 	base_ptr = load_zimage(bzImage_addr, bzImage_size, &load_address);
313 
314 	if (!base_ptr) {
315 		puts("## Kernel loading failed ...\n");
316 		return -1;
317 	}
318 	if (setup_zimage(base_ptr, (char *)base_ptr + COMMAND_LINE_OFFSET,
319 			0, initrd_addr, initrd_size)) {
320 		puts("Setting up boot parameters failed ...\n");
321 		return -1;
322 	}
323 
324 	/* we assume that the kernel is in place */
325 	return boot_linux_kernel((ulong)base_ptr, load_address, false);
326 }
327 
328 U_BOOT_CMD(
329 	zboot, 5, 0,	do_zboot,
330 	"Boot bzImage",
331 	"[addr] [size] [initrd addr] [initrd size]\n"
332 	"      addr -        The optional starting address of the bzimage.\n"
333 	"                    If not set it defaults to the environment\n"
334 	"                    variable \"fileaddr\".\n"
335 	"      size -        The optional size of the bzimage. Defaults to\n"
336 	"                    zero.\n"
337 	"      initrd addr - The address of the initrd image to use, if any.\n"
338 	"      initrd size - The size of the initrd image to use, if any.\n"
339 );
340