summaryrefslogtreecommitdiff
path: root/util/cbmem/cbmem.c
blob: df006847304816620495035a8e7f86471678c05a (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
/*
 * This file is part of the coreboot project.
 *
 * Copyright (C) 2012 The ChromiumOS Authors.  All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <getopt.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/mman.h>

#define ARRAY_SIZE(a) (sizeof(a) / sizeof((a)[0]))
#define MAP_BYTES (1024*1024)

#include "boot/coreboot_tables.h"

typedef uint16_t u16;
typedef uint32_t u32;
typedef uint64_t u64;

#include "cbmem.h"
#include "timestamp.h"

#define CBMEM_VERSION "1.0"

/* verbose output? */
static int verbose = 0;
#define debug(x...) if(verbose) printf(x)

/* File handle used to access /dev/mem */
static int fd;

/*
 * calculate ip checksum (16 bit quantities) on a passed in buffer. In case
 * the buffer length is odd last byte is excluded from the calculation
 */
static u16 ipchcksum(const void *addr, unsigned size)
{
	const u16 *p = addr;
	unsigned i, n = size / 2; /* don't expect odd sized blocks */
	u32 sum = 0;

	for (i = 0; i < n; i++)
		sum += p[i];

	sum = (sum >> 16) + (sum & 0xffff);
	sum += (sum >> 16);
	sum = ~sum & 0xffff;
	return (u16) sum;
}

/*
 * Functions to map / unmap physical memory into virtual address space. These
 * functions always maps 1MB at a time and can only map one area at once.
 */
static void *mapped_virtual;
static void *map_memory(u64 physical)
{
	void *v;
	off_t p;
	int page = getpagesize();

	/* Mapped memory must be aligned to page size */
	p = physical & ~(page - 1);

	debug("Mapping 1MB of physical memory at %zx.\n", p);

	v = mmap(NULL, MAP_BYTES, PROT_READ, MAP_SHARED, fd, p);

	if (v == MAP_FAILED) {
		fprintf(stderr, "Failed to mmap /dev/mem: %s\n",
			strerror(errno));
		exit(1);
	}

	/* Remember what we actually mapped ... */
	mapped_virtual = v;

	/* ... but return address to the physical memory that was requested */
	v += physical & (page-1);

	return v;
}

static void unmap_memory(void)
{
	debug("Unmapping 1MB of virtual memory at %p.\n", mapped_virtual);
	munmap(mapped_virtual, MAP_BYTES);
}

/*
 * Try finding the timestamp table and coreboot cbmem console starting from the
 * passed in memory offset.  Could be called recursively in case a forwarding
 * entry is found.
 *
 * Returns pointer to a memory buffer containg the timestamp table or zero if
 * none found.
 */

static struct lb_cbmem_ref timestamps;
static struct lb_cbmem_ref console;

static int parse_cbtable(u64 address)
{
	int i, found = 0;
	void *buf;

	debug("Looking for coreboot table at %lx\n", address);
	buf = map_memory(address);

	/* look at every 16 bytes within 4K of the base */

	for (i = 0; i < 0x1000; i += 0x10) {
		struct lb_header *lbh;
		struct lb_record* lbr_p;
		void *lbtable;
		int j;

		lbh = (struct lb_header *)(buf + i);
		if (memcmp(lbh->signature, "LBIO", sizeof(lbh->signature)) ||
		    !lbh->header_bytes ||
		    ipchcksum(lbh, sizeof(*lbh))) {
			continue;
		}
		lbtable = buf + i + lbh->header_bytes;

		if (ipchcksum(lbtable, lbh->table_bytes) !=
		    lbh->table_checksum) {
			debug("Signature found, but wrong checksum.\n");
			continue;
		}

		found = 1;
		debug("Found!\n");

		for (j = 0; j < lbh->table_bytes; j += lbr_p->size) {
			/* look for the timestamp table */
			lbr_p = (struct lb_record*) ((char *)lbtable + j);
			debug("  coreboot table entry 0x%02x\n", lbr_p->tag);
			switch (lbr_p->tag) {
			case LB_TAG_TIMESTAMPS: {
				debug("Found timestamp table\n");
				timestamps = *(struct lb_cbmem_ref *) lbr_p;
				continue;
			}
			case LB_TAG_CBMEM_CONSOLE: {
				debug("Found cbmem console\n");
				console = *(struct lb_cbmem_ref *) lbr_p;
				continue;
			}
			case LB_TAG_FORWARD: {
				/*
				 * This is a forwarding entry - repeat the
				 * search at the new address.
				 */
				struct lb_forward lbf_p =
					*(struct lb_forward *) lbr_p;
				unmap_memory();
				return parse_cbtable(lbf_p.forward);
			}
			default:
				break;
			}

		}
	}
	unmap_memory();

	return found;
}

/*
 * read CPU frequency from a sysfs file, return an frequency in Kilohertz as
 * an int or exit on any error.
 */
static u64 get_cpu_freq_KHz(void)
{
	FILE *cpuf;
	char freqs[100];
	int  size;
	char *endp;
	u64 rv;

	const char* freq_file =
		"/sys/devices/system/cpu/cpu0/cpufreq/cpuinfo_max_freq";

	cpuf = fopen(freq_file, "r");
	if (!cpuf) {
		fprintf(stderr, "Could not open %s: %s\n",
			freq_file, strerror(errno));
		exit(1);
	}

	memset(freqs, 0, sizeof(freqs));
	size = fread(freqs, 1, sizeof(freqs), cpuf);
	if (!size || (size == sizeof(freqs))) {
		fprintf(stderr, "Wrong number of bytes(%d) read from %s\n",
			size, freq_file);
		exit(1);
	}
	fclose(cpuf);
	rv = strtoull(freqs, &endp, 10);

	if (*endp == '\0' || *endp == '\n')
		return rv;
	fprintf(stderr, "Wrong formatted value ^%s^ read from %s\n",
		freqs, freq_file);
	exit(1);
}

/*
 * Print an integer in 'normalized' form - with commas separating every three
 * decimal orders. The 'comma' parameter indicates if a comma is needed after
 * the value is printed.
 */
static void print_norm(u64 v, int comma)
{
	int first_triple = 1;

	if (v > 1000) {
		/* print the higher order sections first */
		print_norm(v / 1000, 1);
		first_triple = 0;
	}
	if (first_triple)
		printf("%d", (u32)(v % 1000));
	else
		printf("%3.3d", (u32)(v % 1000));
	if (comma)
		printf(",");
}

/* dump the timestamp table */
static void dump_timestamps(void)
{
	int i;
	u64 cpu_freq_MHz = get_cpu_freq_KHz() / 1000;
	struct timestamp_table *tst_p;

	if (timestamps.tag != LB_TAG_TIMESTAMPS) {
		fprintf(stderr, "No timestamps found in coreboot table.\n");
		return;
	}

	tst_p = (struct timestamp_table *)
			map_memory((unsigned long)timestamps.cbmem_addr);

	printf("%d entries total:\n\n", tst_p->num_entries);
	for (i = 0; i < tst_p->num_entries; i++) {
		const struct timestamp_entry *tse_p = tst_p->entries + i;

		printf("%4d:", tse_p->entry_id);
		print_norm(tse_p->entry_stamp / cpu_freq_MHz, 0);
		if (i) {
			printf(" (");
			print_norm((tse_p->entry_stamp -
				    tse_p[-1].entry_stamp) /
				   cpu_freq_MHz, 0);
			printf(")");
		}
		printf("\n");
	}

	unmap_memory();
}

void print_version(void)
{
	printf("cbmem v%s -- ", CBMEM_VERSION);
	printf("Copyright (C) 2012 The ChromiumOS Authors.  All rights reserved.\n\n");
	printf(
    "This program is free software: you can redistribute it and/or modify\n"
    "it under the terms of the GNU General Public License as published by\n"
    "the Free Software Foundation, version 2 of the License.\n\n"
    "This program is distributed in the hope that it will be useful,\n"
    "but WITHOUT ANY WARRANTY; without even the implied warranty of\n"
    "MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\n"
    "GNU General Public License for more details.\n\n"
    "You should have received a copy of the GNU General Public License\n"
    "along with this program.  If not, see <http://www.gnu.org/licenses/>.\n\n");
}

void print_usage(const char *name)
{
	printf("usage: %s [-vh?]\n", name);
	printf("\n"
	     "   -v | --version:                   print the version\n"
	     "   -h | --help:                      print this help\n"
	     "\n");
	exit(1);
}

int main(int argc, char** argv)
{
	int j;
	static const int possible_base_addresses[] = { 0, 0xf0000 };

	int print_timestamps = 1;

	int opt, option_index = 0;
	static struct option long_options[] = {
		{"verbose", 0, 0, 'V'},
		{"version", 0, 0, 'v'},
		{"help", 0, 0, 'h'},
		{0, 0, 0, 0}
	};
	while ((opt = getopt_long(argc, argv, "Vvh?",
				  long_options, &option_index)) != EOF) {
		switch (opt) {
		case 'V':
			verbose = 1;
			break;
		case 'v':
			print_version();
			exit(0);
			break;
		case 'h':
		case '?':
		default:
			print_usage(argv[0]);
			exit(0);
			break;
		}
	}

	fd = open("/dev/mem", O_RDONLY, 0);
	if (fd < 0) {
		fprintf(stderr, "Failed to gain memory access: %s\n",
			strerror(errno));
		return 1;
	}

	/* Find and parse coreboot table */
	for (j = 0; j < ARRAY_SIZE(possible_base_addresses); j++) {
		if (parse_cbtable(possible_base_addresses[j]))
			break;
	}

	if (print_timestamps)
		dump_timestamps();

	close(fd);
	return 0;
}