xref: /openbmc/u-boot/arch/x86/lib/zimage.c (revision ae485b54)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2011 The Chromium OS Authors.
4  * (C) Copyright 2002
5  * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se>
6  */
7 
8 /*
9  * Linux x86 zImage and bzImage loading
10  *
11  * based on the procdure described in
12  * linux/Documentation/i386/boot.txt
13  */
14 
15 #include <common.h>
16 #include <malloc.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 #include <linux/libfdt.h>
29 
30 /*
31  * Memory lay-out:
32  *
33  * relative to setup_base (which is 0x90000 currently)
34  *
35  *	0x0000-0x7FFF	Real mode kernel
36  *	0x8000-0x8FFF	Stack and heap
37  *	0x9000-0x90FF	Kernel command line
38  */
39 #define DEFAULT_SETUP_BASE	0x90000
40 #define COMMAND_LINE_OFFSET	0x9000
41 #define HEAP_END_OFFSET		0x8e00
42 
43 #define COMMAND_LINE_SIZE	2048
44 
45 static void build_command_line(char *command_line, int auto_boot)
46 {
47 	char *env_command_line;
48 
49 	command_line[0] = '\0';
50 
51 	env_command_line =  env_get("bootargs");
52 
53 	/* set console= argument if we use a serial console */
54 	if (!strstr(env_command_line, "console=")) {
55 		if (!strcmp(env_get("stdout"), "serial")) {
56 
57 			/* We seem to use serial console */
58 			sprintf(command_line, "console=ttyS0,%s ",
59 				env_get("baudrate"));
60 		}
61 	}
62 
63 	if (auto_boot)
64 		strcat(command_line, "auto ");
65 
66 	if (env_command_line)
67 		strcat(command_line, env_command_line);
68 
69 	printf("Kernel command line: \"%s\"\n", command_line);
70 }
71 
72 static int kernel_magic_ok(struct setup_header *hdr)
73 {
74 	if (KERNEL_MAGIC != hdr->boot_flag) {
75 		printf("Error: Invalid Boot Flag "
76 			"(found 0x%04x, expected 0x%04x)\n",
77 			hdr->boot_flag, KERNEL_MAGIC);
78 		return 0;
79 	} else {
80 		printf("Valid Boot Flag\n");
81 		return 1;
82 	}
83 }
84 
85 static int get_boot_protocol(struct setup_header *hdr)
86 {
87 	if (hdr->header == KERNEL_V2_MAGIC) {
88 		printf("Magic signature found\n");
89 		return hdr->version;
90 	} else {
91 		/* Very old kernel */
92 		printf("Magic signature not found\n");
93 		return 0x0100;
94 	}
95 }
96 
97 static int setup_device_tree(struct setup_header *hdr, const void *fdt_blob)
98 {
99 	int bootproto = get_boot_protocol(hdr);
100 	struct setup_data *sd;
101 	int size;
102 
103 	if (bootproto < 0x0209)
104 		return -ENOTSUPP;
105 
106 	if (!fdt_blob)
107 		return 0;
108 
109 	size = fdt_totalsize(fdt_blob);
110 	if (size < 0)
111 		return -EINVAL;
112 
113 	size += sizeof(struct setup_data);
114 	sd = (struct setup_data *)malloc(size);
115 	if (!sd) {
116 		printf("Not enough memory for DTB setup data\n");
117 		return -ENOMEM;
118 	}
119 
120 	sd->next = hdr->setup_data;
121 	sd->type = SETUP_DTB;
122 	sd->len = fdt_totalsize(fdt_blob);
123 	memcpy(sd->data, fdt_blob, sd->len);
124 	hdr->setup_data = (unsigned long)sd;
125 
126 	return 0;
127 }
128 
129 struct boot_params *load_zimage(char *image, unsigned long kernel_size,
130 				ulong *load_addressp)
131 {
132 	struct boot_params *setup_base;
133 	int setup_size;
134 	int bootproto;
135 	int big_image;
136 
137 	struct boot_params *params = (struct boot_params *)image;
138 	struct setup_header *hdr = &params->hdr;
139 
140 	/* base address for real-mode segment */
141 	setup_base = (struct boot_params *)DEFAULT_SETUP_BASE;
142 
143 	if (!kernel_magic_ok(hdr))
144 		return 0;
145 
146 	/* determine size of setup */
147 	if (0 == hdr->setup_sects) {
148 		printf("Setup Sectors = 0 (defaulting to 4)\n");
149 		setup_size = 5 * 512;
150 	} else {
151 		setup_size = (hdr->setup_sects + 1) * 512;
152 	}
153 
154 	printf("Setup Size = 0x%8.8lx\n", (ulong)setup_size);
155 
156 	if (setup_size > SETUP_MAX_SIZE)
157 		printf("Error: Setup is too large (%d bytes)\n", setup_size);
158 
159 	/* determine boot protocol version */
160 	bootproto = get_boot_protocol(hdr);
161 
162 	printf("Using boot protocol version %x.%02x\n",
163 	       (bootproto & 0xff00) >> 8, bootproto & 0xff);
164 
165 	if (bootproto >= 0x0200) {
166 		if (hdr->setup_sects >= 15) {
167 			printf("Linux kernel version %s\n",
168 				(char *)params +
169 				hdr->kernel_version + 0x200);
170 		} else {
171 			printf("Setup Sectors < 15 - "
172 				"Cannot print kernel version.\n");
173 		}
174 	}
175 
176 	/* Determine image type */
177 	big_image = (bootproto >= 0x0200) &&
178 		    (hdr->loadflags & BIG_KERNEL_FLAG);
179 
180 	/* Determine load address */
181 	if (big_image)
182 		*load_addressp = BZIMAGE_LOAD_ADDR;
183 	else
184 		*load_addressp = ZIMAGE_LOAD_ADDR;
185 
186 	printf("Building boot_params at 0x%8.8lx\n", (ulong)setup_base);
187 	memset(setup_base, 0, sizeof(*setup_base));
188 	setup_base->hdr = params->hdr;
189 
190 	if (bootproto >= 0x0204)
191 		kernel_size = hdr->syssize * 16;
192 	else
193 		kernel_size -= setup_size;
194 
195 	if (bootproto == 0x0100) {
196 		/*
197 		 * A very old kernel MUST have its real-mode code
198 		 * loaded at 0x90000
199 		 */
200 		if ((ulong)setup_base != 0x90000) {
201 			/* Copy the real-mode kernel */
202 			memmove((void *)0x90000, setup_base, setup_size);
203 
204 			/* Copy the command line */
205 			memmove((void *)0x99000,
206 				(u8 *)setup_base + COMMAND_LINE_OFFSET,
207 				COMMAND_LINE_SIZE);
208 
209 			 /* Relocated */
210 			setup_base = (struct boot_params *)0x90000;
211 		}
212 
213 		/* It is recommended to clear memory up to the 32K mark */
214 		memset((u8 *)0x90000 + setup_size, 0,
215 		       SETUP_MAX_SIZE - setup_size);
216 	}
217 
218 	if (big_image) {
219 		if (kernel_size > BZIMAGE_MAX_SIZE) {
220 			printf("Error: bzImage kernel too big! "
221 				"(size: %ld, max: %d)\n",
222 				kernel_size, BZIMAGE_MAX_SIZE);
223 			return 0;
224 		}
225 	} else if ((kernel_size) > ZIMAGE_MAX_SIZE) {
226 		printf("Error: zImage kernel too big! (size: %ld, max: %d)\n",
227 		       kernel_size, ZIMAGE_MAX_SIZE);
228 		return 0;
229 	}
230 
231 	printf("Loading %s at address %lx (%ld bytes)\n",
232 	       big_image ? "bzImage" : "zImage", *load_addressp, kernel_size);
233 
234 	memmove((void *)*load_addressp, image + setup_size, kernel_size);
235 
236 	return setup_base;
237 }
238 
239 int setup_zimage(struct boot_params *setup_base, char *cmd_line, int auto_boot,
240 		 unsigned long initrd_addr, unsigned long initrd_size)
241 {
242 	struct setup_header *hdr = &setup_base->hdr;
243 	int bootproto = get_boot_protocol(hdr);
244 
245 	setup_base->e820_entries = install_e820_map(
246 		ARRAY_SIZE(setup_base->e820_map), setup_base->e820_map);
247 
248 	if (bootproto == 0x0100) {
249 		setup_base->screen_info.cl_magic = COMMAND_LINE_MAGIC;
250 		setup_base->screen_info.cl_offset = COMMAND_LINE_OFFSET;
251 	}
252 	if (bootproto >= 0x0200) {
253 		hdr->type_of_loader = 8;
254 
255 		if (initrd_addr) {
256 			printf("Initial RAM disk at linear address "
257 			       "0x%08lx, size %ld bytes\n",
258 			       initrd_addr, initrd_size);
259 
260 			hdr->ramdisk_image = initrd_addr;
261 			hdr->ramdisk_size = initrd_size;
262 		}
263 	}
264 
265 	if (bootproto >= 0x0201) {
266 		hdr->heap_end_ptr = HEAP_END_OFFSET;
267 		hdr->loadflags |= HEAP_FLAG;
268 	}
269 
270 	if (cmd_line) {
271 		if (bootproto >= 0x0202) {
272 			hdr->cmd_line_ptr = (uintptr_t)cmd_line;
273 		} else if (bootproto >= 0x0200) {
274 			setup_base->screen_info.cl_magic = COMMAND_LINE_MAGIC;
275 			setup_base->screen_info.cl_offset =
276 				(uintptr_t)cmd_line - (uintptr_t)setup_base;
277 
278 			hdr->setup_move_size = 0x9100;
279 		}
280 
281 		/* build command line at COMMAND_LINE_OFFSET */
282 		build_command_line(cmd_line, auto_boot);
283 	}
284 
285 #ifdef CONFIG_INTEL_MID
286 	if (bootproto >= 0x0207)
287 		hdr->hardware_subarch = X86_SUBARCH_INTEL_MID;
288 #endif
289 
290 #ifdef CONFIG_GENERATE_ACPI_TABLE
291 	if (bootproto >= 0x020e)
292 		hdr->acpi_rsdp_addr = acpi_get_rsdp_addr();
293 #endif
294 
295 	setup_device_tree(hdr, (const void *)env_get_hex("fdtaddr", 0));
296 	setup_video(&setup_base->screen_info);
297 
298 	return 0;
299 }
300 
301 void setup_pcat_compatibility(void)
302 	__attribute__((weak, alias("__setup_pcat_compatibility")));
303 
304 void __setup_pcat_compatibility(void)
305 {
306 }
307 
308 int do_zboot(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
309 {
310 	struct boot_params *base_ptr;
311 	void *bzImage_addr = NULL;
312 	ulong load_address;
313 	char *s;
314 	ulong bzImage_size = 0;
315 	ulong initrd_addr = 0;
316 	ulong initrd_size = 0;
317 
318 	disable_interrupts();
319 
320 	/* Setup board for maximum PC/AT Compatibility */
321 	setup_pcat_compatibility();
322 
323 	if (argc >= 2) {
324 		/* argv[1] holds the address of the bzImage */
325 		s = argv[1];
326 	} else {
327 		s = env_get("fileaddr");
328 	}
329 
330 	if (s)
331 		bzImage_addr = (void *)simple_strtoul(s, NULL, 16);
332 
333 	if (argc >= 3) {
334 		/* argv[2] holds the size of the bzImage */
335 		bzImage_size = simple_strtoul(argv[2], NULL, 16);
336 	}
337 
338 	if (argc >= 4)
339 		initrd_addr = simple_strtoul(argv[3], NULL, 16);
340 	if (argc >= 5)
341 		initrd_size = simple_strtoul(argv[4], NULL, 16);
342 
343 	/* Lets look for */
344 	base_ptr = load_zimage(bzImage_addr, bzImage_size, &load_address);
345 
346 	if (!base_ptr) {
347 		puts("## Kernel loading failed ...\n");
348 		return -1;
349 	}
350 	if (setup_zimage(base_ptr, (char *)base_ptr + COMMAND_LINE_OFFSET,
351 			0, initrd_addr, initrd_size)) {
352 		puts("Setting up boot parameters failed ...\n");
353 		return -1;
354 	}
355 
356 	/* we assume that the kernel is in place */
357 	return boot_linux_kernel((ulong)base_ptr, load_address, false);
358 }
359 
360 U_BOOT_CMD(
361 	zboot, 5, 0,	do_zboot,
362 	"Boot bzImage",
363 	"[addr] [size] [initrd addr] [initrd size]\n"
364 	"      addr -        The optional starting address of the bzimage.\n"
365 	"                    If not set it defaults to the environment\n"
366 	"                    variable \"fileaddr\".\n"
367 	"      size -        The optional size of the bzimage. Defaults to\n"
368 	"                    zero.\n"
369 	"      initrd addr - The address of the initrd image to use, if any.\n"
370 	"      initrd size - The size of the initrd image to use, if any.\n"
371 );
372