summaryrefslogtreecommitdiff
path: root/board/st/u8500/cmd_cdump.c
blob: 87ae2a7934eb77e33329b582d52fc3f8c2599ea2 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
/*
 * Copyright (C) ST-Ericsson SA 2010
 *
 * Author: Spjalle Joelson for ST-Ericsson
 * Licensed under GPLv2.
 *
 * Cleanups and comments: Michael Brandt <michael.brandt@stericsson.com>
 */

/* cmd_cdump.c - crash dump commands, require FAT write support */

#include <common.h>
#include <command.h>
#include "malloc.h"
#include <mmc.h>

#include <asm/setup.h>
#include <elf.h>
#include <fat.h>

/*
 * Note: with the Rockbox FAT support, the file path must be an absolute path,
 * i.e. with leading /.
 */
static char *crash_filename = "/cdump.elf";

/*
 * Check ELF header
 */
static int check_elfhdr(Elf32_Ehdr *elfhdr_addr)
{
	unsigned char *elfhdr = (unsigned char *) elfhdr_addr;

	/* check ELF core image header MAGIC */
	if (memcmp(elfhdr, ELFMAG, SELFMAG) != 0)
		return 1;

	/* check that this is ELF32 */
	if (elfhdr[EI_CLASS] == ELFCLASS32)
		return 0;

	return 1;
}

/*
 * Write a chunk
 */
static int write_chunk(int fd, void *addr, size_t count)
{
	size_t bytes;

	bytes = write(fd, addr, count);
	if (bytes != count) {
		printf("write error\n");
		close(fd);
		return -1;
	}
	return 0;
}

/*
 * Write a big chunk with 'progress' indicator '.' for every MiB
 */
static int write_big_chunk(int fd, void *addr, size_t count)
{
	unsigned char *a = addr;
	size_t total = 0;

	if (count < 0x100000)
		return write_chunk(fd, addr, count);
	/* if large chunk then print dot to show progress */
	while (total < count) {
		size_t bytes = count - total;

		if (bytes > 0x100000)
			bytes = 0x100000;
		if (write_chunk(fd, a, bytes))
			return -1;
		putc('.');
		total += bytes;
		a += bytes;
	}
	putc('\n');
	return 0;
}

/*
 * Open the dump file for writing. Create if it not exists.
 * Note that with the Rockbox FAT support, the file path must be an absolute
 * path, i.e. with leading /.
 */
static int open_create(const char *filename)
{
	int fd;

	fd = open(filename, O_WRONLY | O_CREAT);
	if (fd < 0)
		printf("%s open error\n", filename);
	return fd;
}

/*
 * Check program header and segment
 * Truncate note segments.
 * Return segment size.
 */
static u32 check_phdr(Elf32_Phdr *proghdr)
{
	u32 i;
	u32 *note;
	Elf32_Phdr *phdr = proghdr;

	if (phdr->p_type == PT_NOTE) {
		/* see Linux kernel/kexec.c:append_elf_note() */
		note = (u32 *)(phdr->p_paddr);
		for (i = 0; i < phdr->p_filesz/4;) {
			if (note[i] == 0 && note[i+1] == 0 && note[i+2] == 0)
				return i*4;
			i += 3 + (note[i] + 3) / 4 + (note[i+1] + 3) / 4;
		}
	}

	return phdr->p_filesz;
}

/*
 * Dump crash to file
 */
static int write_elf(Elf32_Ehdr *elfhdr_addr, int fd)
{
	Elf32_Ehdr *oldhdr = elfhdr_addr;
	Elf32_Ehdr *ehdr;
	Elf32_Phdr *phdr;
	u32 i;
	u32 offset;
	u32 tot;
	u32 phdr_cnt;
	u32 notes_cnt = 0;
	u32 save;
	u32 len;

	offset = oldhdr->e_ehsize + oldhdr->e_phentsize * oldhdr->e_phnum;
	ehdr = (Elf32_Ehdr *) malloc(offset);
	if (ehdr == NULL) {
		debug("elf header alloc error\n");
		return -1;
	}
	memcpy(ehdr, oldhdr, offset);

	/*
	 * check program header entries and update length
	 * for merged PT_NOTE segments
	 */
	tot = 0;
	phdr_cnt = ehdr->e_phnum;
	debug("phdr_cnt=%d\n", phdr_cnt);
	for (i = 0; i < phdr_cnt; i++) {
		phdr = (Elf32_Phdr *) ((char *) ehdr + ehdr->e_ehsize +
				       i * ehdr->e_phentsize);
		len = check_phdr(phdr);
		debug("prog hdr %d: %x ad %x len %x adjusted to %x\n",
		      i, (u32) phdr, phdr->p_paddr, phdr->p_filesz, len);
		phdr->p_filesz = len;
		phdr->p_memsz = len;
		if (phdr->p_type == PT_NOTE) {	/* note segment */
			tot += len;
			notes_cnt++;
		}
	}
	debug("Length of %d note segments: %x\n", notes_cnt, tot);

	/*
	 * all PT_NOTE segments have been merged into one.
	 * Update ELF Header accordingly
	 */
	ehdr->e_phnum = phdr_cnt - notes_cnt + 1;

	/* write elf header into file on sdcard */
	if (write_chunk(fd, ehdr, (size_t) ehdr->e_ehsize)) {
		free(ehdr);
		return -1;
	}

	/* write program headers into file on sdcard */
	offset = ehdr->e_ehsize + ehdr->e_phentsize * ehdr->e_phnum;
	debug("Write Phdr: proghdr_cnt=%d\n", phdr_cnt);
	for (i = 0; i < phdr_cnt; i++) {
		phdr = (Elf32_Phdr *) ((char *)ehdr + ehdr->e_ehsize +
				       i * ehdr->e_phentsize);
		save = phdr->p_filesz;
		if (i == 0) {
			phdr->p_filesz = tot;
			phdr->p_memsz = tot;
		} else if (phdr->p_type == PT_NOTE) /* note segment */
			continue;
		phdr->p_offset = offset;
		debug("prog hdr %d: %x ad %x len %x off %x\n",
		       i, (u32) phdr, phdr->p_paddr, phdr->p_filesz,
		       phdr->p_offset);
		offset += phdr->p_filesz;
		if (write_chunk(fd, (void *) phdr, (size_t)
				ehdr->e_phentsize)) {
			free(ehdr);
			return -1;
		}
		phdr->p_filesz = save;
		phdr->p_memsz = save;
	}

	/* write segments into file on sdcard */
	debug("write segments...\n");
	for (i = 0; i < phdr_cnt; i++) {
		phdr = (Elf32_Phdr *) ((char *) ehdr + ehdr->e_ehsize +
				       i * ehdr->e_phentsize);
		if (phdr->p_type > PT_NULL) {
			if (write_big_chunk(fd, (void *) phdr->p_paddr,
							 phdr->p_filesz)) {
				free(ehdr);
				return -1;
			}
		}
	}

	free(ehdr);
	return 0;
}

/*
 * Dump crash to file
 */
static int dump_elf(Elf32_Ehdr *elfhdr_addr, char *filename)
{
	int fd;
	int rc;

	printf("Crash dump to %s\n", filename);
	fd = open_create(filename);
	if (fd < 0)
		return 1;
	rc = write_elf(elfhdr_addr, fd);
	close(fd);

	return rc;
}

/*
 * Wait for MMC/SD card to be inserted
 */
static int wait_for_mmc(void)
{
	struct mmc *mmc;

        mmc = find_mmc_device(CONFIG_MMC_DEV_NUM);
	if (!mmc) {
		printf("MMC device %d not found\n", CONFIG_MMC_DEV_NUM);
		return 1;
	}
	while (mmc_init(mmc) != 0) {
		printf("Insert MMC/SD card or press ctrl-c to abort\n");
		putc('.');
		udelay(500000);
		/* check for ctrl-c to abort... */
		if (ctrlc()) {
			puts("Abort\n");
			return -1;
		}
	}
	return 0;
}

/*
 * Find kexec/kdump ATAG command line
 */
static char *get_atag_cmdline(void)
{
	ulong atag_offset = 0x1000; /* 4k offset from memory start */
	ulong offset = 0x8000;      /* 32k offset from memory start */
	/*
	 * Get pointer to ATAG area, somewhere below U-boot image.
	 * Above values are hard coded in the kexec-tools.
	 */
	u32 * atags = (u32 *)(_armboot_start - offset + atag_offset);
	u32 i = 0;

	/*
	 * ATAG command line: \0 terminated string.
	 * The list ends with an ATAG_NONE node.
	 */
	for (i = 0; (atags[i] != 0) && (atags[i+1] != ATAG_NONE);
			i += atags[i]) {

		if (atags[i+1] == ATAG_CMDLINE)
			return (char *) &atags[i+2];
		/* sanity check before checking next ATAG */
		if (atags[i] > (offset - atag_offset) / sizeof(u32) - i)
			return NULL;
		if ((atags[i] + i) < i) /* cannot step backwards */
			return NULL;
	}

	return NULL;
}

/*
 * Find out where the kdump elf header is.
 */
static Elf32_Ehdr *get_elfhdr_addr(void)
{
	const char elfcorehdr[] = "elfcorehdr=";
	char *cmd;
	char *atag_cmdline = get_atag_cmdline();

	if (atag_cmdline != NULL) {
		cmd = strstr(atag_cmdline, elfcorehdr);
		if (cmd != NULL) {
			cmd += strlen(elfcorehdr);
			return (Elf32_Ehdr *) simple_strtoul(cmd, NULL, 16);
		}
	}
	return NULL;
}

/*
 * Dump crash to file (typically FAT file on SD/MMC).
 */
static int crashdump(Elf32_Ehdr *elfhdr_addr, char *filename)
{
	int rc;
	block_dev_desc_t *dev_desc=NULL;

	rc = wait_for_mmc();
	if (rc == 0) {
		dev_desc = get_dev("mmc", 1);	/* mmc 1 */
		rc = fat_register_device(dev_desc, 1); /* part 1 */
		if (rc != 0) {
			printf("crashdump: fat_register_device failed %d\n",
					rc);
			return -1;
		}
		rc = dump_elf(elfhdr_addr, filename);
	}

	if (rc != 0)
		printf("crashdump: error writing dump to %s\n", filename);

	return rc;
}

/*
 * Dump crash to file (typically FAT file on SD/MMC).
 */
static int do_checkcrash(cmd_tbl_t *cmdtp, int flag, int argc, char *argv[])
{
	Elf32_Ehdr *elfhdr_addr;
	int rc = -1;

	elfhdr_addr = get_elfhdr_addr();
	if (elfhdr_addr != NULL)
		rc = check_elfhdr(elfhdr_addr);
	if (rc == 0) {
		printf("crash dump elf header found. Dumping to card...\n");
		/* stop autoboot in case we were called by preboot */
		setenv("bootdelay", "-1");
		rc = crashdump(elfhdr_addr, crash_filename);
		if (rc != 0)
			printf("checkcrash: error writing dump from %x to %s\n"
			       , (u32) elfhdr_addr, crash_filename);
	}
	return rc;
}

U_BOOT_CMD(
	checkcrash,	1,	0,	do_checkcrash,
	"check ATAGS from crash and dump to file",
	"    - dump crash info to file and stop autoboot\n"
);