xref: /openbmc/u-boot/cmd/elf.c (revision 85231c08)
1 /*
2  * Copyright (c) 2001 William L. Pitts
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms are freely
6  * permitted provided that the above copyright notice and this
7  * paragraph and the following disclaimer are duplicated in all
8  * such forms.
9  *
10  * This software is provided "AS IS" and without any express or
11  * implied warranties, including, without limitation, the implied
12  * warranties of merchantability and fitness for a particular
13  * purpose.
14  */
15 
16 #include <common.h>
17 #include <command.h>
18 #include <elf.h>
19 #include <net.h>
20 #include <vxworks.h>
21 #ifdef CONFIG_X86
22 #include <asm/e820.h>
23 #include <linux/linkage.h>
24 #endif
25 
26 /*
27  * A very simple elf loader, assumes the image is valid, returns the
28  * entry point address.
29  */
30 static unsigned long load_elf_image_phdr(unsigned long addr)
31 {
32 	Elf32_Ehdr *ehdr; /* Elf header structure pointer */
33 	Elf32_Phdr *phdr; /* Program header structure pointer */
34 	int i;
35 
36 	ehdr = (Elf32_Ehdr *)addr;
37 	phdr = (Elf32_Phdr *)(addr + ehdr->e_phoff);
38 
39 	/* Load each program header */
40 	for (i = 0; i < ehdr->e_phnum; ++i) {
41 		void *dst = (void *)(uintptr_t)phdr->p_paddr;
42 		void *src = (void *)addr + phdr->p_offset;
43 		debug("Loading phdr %i to 0x%p (%i bytes)\n",
44 		      i, dst, phdr->p_filesz);
45 		if (phdr->p_filesz)
46 			memcpy(dst, src, phdr->p_filesz);
47 		if (phdr->p_filesz != phdr->p_memsz)
48 			memset(dst + phdr->p_filesz, 0x00,
49 			       phdr->p_memsz - phdr->p_filesz);
50 		flush_cache((unsigned long)dst, phdr->p_filesz);
51 		++phdr;
52 	}
53 
54 	return ehdr->e_entry;
55 }
56 
57 static unsigned long load_elf_image_shdr(unsigned long addr)
58 {
59 	Elf32_Ehdr *ehdr; /* Elf header structure pointer */
60 	Elf32_Shdr *shdr; /* Section header structure pointer */
61 	unsigned char *strtab = 0; /* String table pointer */
62 	unsigned char *image; /* Binary image pointer */
63 	int i; /* Loop counter */
64 
65 	ehdr = (Elf32_Ehdr *)addr;
66 
67 	/* Find the section header string table for output info */
68 	shdr = (Elf32_Shdr *)(addr + ehdr->e_shoff +
69 			     (ehdr->e_shstrndx * sizeof(Elf32_Shdr)));
70 
71 	if (shdr->sh_type == SHT_STRTAB)
72 		strtab = (unsigned char *)(addr + shdr->sh_offset);
73 
74 	/* Load each appropriate section */
75 	for (i = 0; i < ehdr->e_shnum; ++i) {
76 		shdr = (Elf32_Shdr *)(addr + ehdr->e_shoff +
77 				     (i * sizeof(Elf32_Shdr)));
78 
79 		if (!(shdr->sh_flags & SHF_ALLOC) ||
80 		    shdr->sh_addr == 0 || shdr->sh_size == 0) {
81 			continue;
82 		}
83 
84 		if (strtab) {
85 			debug("%sing %s @ 0x%08lx (%ld bytes)\n",
86 			      (shdr->sh_type == SHT_NOBITS) ? "Clear" : "Load",
87 			       &strtab[shdr->sh_name],
88 			       (unsigned long)shdr->sh_addr,
89 			       (long)shdr->sh_size);
90 		}
91 
92 		if (shdr->sh_type == SHT_NOBITS) {
93 			memset((void *)(uintptr_t)shdr->sh_addr, 0,
94 			       shdr->sh_size);
95 		} else {
96 			image = (unsigned char *)addr + shdr->sh_offset;
97 			memcpy((void *)(uintptr_t)shdr->sh_addr,
98 			       (const void *)image, shdr->sh_size);
99 		}
100 		flush_cache(shdr->sh_addr, shdr->sh_size);
101 	}
102 
103 	return ehdr->e_entry;
104 }
105 
106 /* Allow ports to override the default behavior */
107 static unsigned long do_bootelf_exec(ulong (*entry)(int, char * const[]),
108 				     int argc, char * const argv[])
109 {
110 	unsigned long ret;
111 
112 	/*
113 	 * pass address parameter as argv[0] (aka command name),
114 	 * and all remaining args
115 	 */
116 	ret = entry(argc, argv);
117 
118 	return ret;
119 }
120 
121 /*
122  * Determine if a valid ELF image exists at the given memory location.
123  * First look at the ELF header magic field, then make sure that it is
124  * executable.
125  */
126 int valid_elf_image(unsigned long addr)
127 {
128 	Elf32_Ehdr *ehdr; /* Elf header structure pointer */
129 
130 	ehdr = (Elf32_Ehdr *)addr;
131 
132 	if (!IS_ELF(*ehdr)) {
133 		printf("## No elf image at address 0x%08lx\n", addr);
134 		return 0;
135 	}
136 
137 	if (ehdr->e_type != ET_EXEC) {
138 		printf("## Not a 32-bit elf image at address 0x%08lx\n", addr);
139 		return 0;
140 	}
141 
142 	return 1;
143 }
144 
145 /* Interpreter command to boot an arbitrary ELF image from memory */
146 int do_bootelf(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
147 {
148 	unsigned long addr; /* Address of the ELF image */
149 	unsigned long rc; /* Return value from user code */
150 	char *sload = NULL;
151 	const char *ep = env_get("autostart");
152 	int rcode = 0;
153 
154 	/* Consume 'bootelf' */
155 	argc--; argv++;
156 
157 	/* Check for flag. */
158 	if (argc >= 1 && (argv[0][0] == '-' && \
159 				(argv[0][1] == 'p' || argv[0][1] == 's'))) {
160 		sload = argv[0];
161 		/* Consume flag. */
162 		argc--; argv++;
163 	}
164 	/* Check for address. */
165 	if (argc >= 1 && strict_strtoul(argv[0], 16, &addr) != -EINVAL) {
166 		/* Consume address */
167 		argc--; argv++;
168 	} else
169 		addr = load_addr;
170 
171 	if (!valid_elf_image(addr))
172 		return 1;
173 
174 	if (sload && sload[1] == 'p')
175 		addr = load_elf_image_phdr(addr);
176 	else
177 		addr = load_elf_image_shdr(addr);
178 
179 	if (ep && !strcmp(ep, "no"))
180 		return rcode;
181 
182 	printf("## Starting application at 0x%08lx ...\n", addr);
183 
184 	/*
185 	 * pass address parameter as argv[0] (aka command name),
186 	 * and all remaining args
187 	 */
188 	rc = do_bootelf_exec((void *)addr, argc, argv);
189 	if (rc != 0)
190 		rcode = 1;
191 
192 	printf("## Application terminated, rc = 0x%lx\n", rc);
193 
194 	return rcode;
195 }
196 
197 /*
198  * Interpreter command to boot VxWorks from a memory image.  The image can
199  * be either an ELF image or a raw binary.  Will attempt to setup the
200  * bootline and other parameters correctly.
201  */
202 int do_bootvx(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
203 {
204 	unsigned long addr; /* Address of image */
205 	unsigned long bootaddr; /* Address to put the bootline */
206 	char *bootline; /* Text of the bootline */
207 	char *tmp; /* Temporary char pointer */
208 	char build_buf[128]; /* Buffer for building the bootline */
209 	int ptr = 0;
210 #ifdef CONFIG_X86
211 	struct e820info *info;
212 	struct e820entry *data;
213 #endif
214 
215 	/*
216 	 * Check the loadaddr variable.
217 	 * If we don't know where the image is then we're done.
218 	 */
219 	if (argc < 2)
220 		addr = load_addr;
221 	else
222 		addr = simple_strtoul(argv[1], NULL, 16);
223 
224 #if defined(CONFIG_CMD_NET)
225 	/*
226 	 * Check to see if we need to tftp the image ourselves
227 	 * before starting
228 	 */
229 	if ((argc == 2) && (strcmp(argv[1], "tftp") == 0)) {
230 		if (net_loop(TFTPGET) <= 0)
231 			return 1;
232 		printf("Automatic boot of VxWorks image at address 0x%08lx ...\n",
233 			addr);
234 	}
235 #endif
236 
237 	/*
238 	 * This should equate to
239 	 * NV_RAM_ADRS + NV_BOOT_OFFSET + NV_ENET_OFFSET
240 	 * from the VxWorks BSP header files.
241 	 * This will vary from board to board
242 	 */
243 #if defined(CONFIG_SYS_VXWORKS_MAC_PTR)
244 	tmp = (char *)CONFIG_SYS_VXWORKS_MAC_PTR;
245 	eth_env_get_enetaddr("ethaddr", (uchar *)build_buf);
246 	memcpy(tmp, build_buf, 6);
247 #else
248 	puts("## Ethernet MAC address not copied to NV RAM\n");
249 #endif
250 
251 	/*
252 	 * Use bootaddr to find the location in memory that VxWorks
253 	 * will look for the bootline string. The default value is
254 	 * (LOCAL_MEM_LOCAL_ADRS + BOOT_LINE_OFFSET) as defined by
255 	 * VxWorks BSP. For example, on PowerPC it defaults to 0x4200.
256 	 */
257 	tmp = env_get("bootaddr");
258 	if (!tmp) {
259 		printf("## VxWorks bootline address not specified\n");
260 	} else {
261 		bootaddr = simple_strtoul(tmp, NULL, 16);
262 
263 		/*
264 		 * Check to see if the bootline is defined in the 'bootargs'
265 		 * parameter. If it is not defined, we may be able to
266 		 * construct the info.
267 		 */
268 		bootline = env_get("bootargs");
269 		if (bootline) {
270 			memcpy((void *)bootaddr, bootline,
271 			       max(strlen(bootline), (size_t)255));
272 			flush_cache(bootaddr, max(strlen(bootline),
273 						  (size_t)255));
274 		} else {
275 			tmp = env_get("bootdev");
276 			if (tmp) {
277 				strcpy(build_buf, tmp);
278 				ptr = strlen(tmp);
279 			} else
280 				printf("## VxWorks boot device not specified\n");
281 
282 			tmp = env_get("bootfile");
283 			if (tmp)
284 				ptr += sprintf(build_buf + ptr,
285 					       "host:%s ", tmp);
286 			else
287 				ptr += sprintf(build_buf + ptr,
288 					       "host:vxWorks ");
289 
290 			/*
291 			 * The following parameters are only needed if 'bootdev'
292 			 * is an ethernet device, otherwise they are optional.
293 			 */
294 			tmp = env_get("ipaddr");
295 			if (tmp) {
296 				ptr += sprintf(build_buf + ptr, "e=%s", tmp);
297 				tmp = env_get("netmask");
298 				if (tmp) {
299 					u32 mask = env_get_ip("netmask").s_addr;
300 					ptr += sprintf(build_buf + ptr,
301 						       ":%08x ", ntohl(mask));
302 				} else {
303 					ptr += sprintf(build_buf + ptr, " ");
304 				}
305 			}
306 
307 			tmp = env_get("serverip");
308 			if (tmp)
309 				ptr += sprintf(build_buf + ptr, "h=%s ", tmp);
310 
311 			tmp = env_get("gatewayip");
312 			if (tmp)
313 				ptr += sprintf(build_buf + ptr, "g=%s ", tmp);
314 
315 			tmp = env_get("hostname");
316 			if (tmp)
317 				ptr += sprintf(build_buf + ptr, "tn=%s ", tmp);
318 
319 			tmp = env_get("othbootargs");
320 			if (tmp) {
321 				strcpy(build_buf + ptr, tmp);
322 				ptr += strlen(tmp);
323 			}
324 
325 			memcpy((void *)bootaddr, build_buf,
326 			       max(strlen(build_buf), (size_t)255));
327 			flush_cache(bootaddr, max(strlen(build_buf),
328 						  (size_t)255));
329 		}
330 
331 		printf("## Using bootline (@ 0x%lx): %s\n", bootaddr,
332 		       (char *)bootaddr);
333 	}
334 
335 #ifdef CONFIG_X86
336 	/*
337 	 * Since E820 information is critical to the kernel, if we don't
338 	 * specify these in the environments, use a default one.
339 	 */
340 	tmp = env_get("e820data");
341 	if (tmp)
342 		data = (struct e820entry *)simple_strtoul(tmp, NULL, 16);
343 	else
344 		data = (struct e820entry *)VXWORKS_E820_DATA_ADDR;
345 	tmp = env_get("e820info");
346 	if (tmp)
347 		info = (struct e820info *)simple_strtoul(tmp, NULL, 16);
348 	else
349 		info = (struct e820info *)VXWORKS_E820_INFO_ADDR;
350 
351 	memset(info, 0, sizeof(struct e820info));
352 	info->sign = E820_SIGNATURE;
353 	info->entries = install_e820_map(E820MAX, data);
354 	info->addr = (info->entries - 1) * sizeof(struct e820entry) +
355 		     VXWORKS_E820_DATA_ADDR;
356 #endif
357 
358 	/*
359 	 * If the data at the load address is an elf image, then
360 	 * treat it like an elf image. Otherwise, assume that it is a
361 	 * binary image.
362 	 */
363 	if (valid_elf_image(addr))
364 		addr = load_elf_image_phdr(addr);
365 	else
366 		puts("## Not an ELF image, assuming binary\n");
367 
368 	printf("## Starting vxWorks at 0x%08lx ...\n", addr);
369 
370 	dcache_disable();
371 #ifdef CONFIG_X86
372 	/* VxWorks on x86 uses stack to pass parameters */
373 	((asmlinkage void (*)(int))addr)(0);
374 #else
375 	((void (*)(int))addr)(0);
376 #endif
377 
378 	puts("## vxWorks terminated\n");
379 
380 	return 1;
381 }
382 
383 U_BOOT_CMD(
384 	bootelf, CONFIG_SYS_MAXARGS, 0, do_bootelf,
385 	"Boot from an ELF image in memory",
386 	"[-p|-s] [address]\n"
387 	"\t- load ELF image at [address] via program headers (-p)\n"
388 	"\t  or via section headers (-s)"
389 );
390 
391 U_BOOT_CMD(
392 	bootvx, 2, 0, do_bootvx,
393 	"Boot vxWorks from an ELF image",
394 	" [address] - load address of vxWorks ELF image."
395 );
396