xref: /openbmc/u-boot/cmd/eeprom.c (revision fb1b7712)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * (C) Copyright 2000, 2001
4  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5  */
6 
7 /*
8  * Support for read and write access to EEPROM like memory devices. This
9  * includes regular EEPROM as well as  FRAM (ferroelectic nonvolaile RAM).
10  * FRAM devices read and write data at bus speed. In particular, there is no
11  * write delay. Also, there is no limit imposed on the number of bytes that can
12  * be transferred with a single read or write.
13  *
14  * Use the following configuration options to ensure no unneeded performance
15  * degradation (typical for EEPROM) is incured for FRAM memory:
16  *
17  * #define CONFIG_SYS_I2C_FRAM
18  * #undef CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS
19  *
20  */
21 
22 #include <common.h>
23 #include <config.h>
24 #include <command.h>
25 #include <i2c.h>
26 #include <eeprom_layout.h>
27 
28 #ifndef	CONFIG_SYS_I2C_SPEED
29 #define	CONFIG_SYS_I2C_SPEED	50000
30 #endif
31 
32 #ifndef CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS
33 #define CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS	0
34 #endif
35 
36 #ifndef CONFIG_SYS_EEPROM_PAGE_WRITE_BITS
37 #define CONFIG_SYS_EEPROM_PAGE_WRITE_BITS	8
38 #endif
39 
40 #ifndef	I2C_RXTX_LEN
41 #define I2C_RXTX_LEN	128
42 #endif
43 
44 #define	EEPROM_PAGE_SIZE	(1 << CONFIG_SYS_EEPROM_PAGE_WRITE_BITS)
45 #define	EEPROM_PAGE_OFFSET(x)	((x) & (EEPROM_PAGE_SIZE - 1))
46 
47 /*
48  * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 2 (16-bit EEPROM address) offset is
49  *   0x000nxxxx for EEPROM address selectors at n, offset xxxx in EEPROM.
50  *
51  * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1 (8-bit EEPROM page address) offset is
52  *   0x00000nxx for EEPROM address selectors and page number at n.
53  */
54 #if !defined(CONFIG_SPI) || defined(CONFIG_ENV_EEPROM_IS_ON_I2C)
55 #if !defined(CONFIG_SYS_I2C_EEPROM_ADDR_LEN) || \
56 	(CONFIG_SYS_I2C_EEPROM_ADDR_LEN < 1) || \
57 	(CONFIG_SYS_I2C_EEPROM_ADDR_LEN > 2)
58 #error CONFIG_SYS_I2C_EEPROM_ADDR_LEN must be 1 or 2
59 #endif
60 #endif
61 
62 __weak int eeprom_write_enable(unsigned dev_addr, int state)
63 {
64 	return 0;
65 }
66 
67 void eeprom_init(int bus)
68 {
69 	/* I2C EEPROM */
70 #if defined(CONFIG_SYS_I2C)
71 	if (bus >= 0)
72 		i2c_set_bus_num(bus);
73 	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
74 #endif
75 }
76 
77 static int eeprom_addr(unsigned dev_addr, unsigned offset, uchar *addr)
78 {
79 	unsigned blk_off;
80 	int alen;
81 
82 	blk_off = offset & 0xff;	/* block offset */
83 #if CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1
84 	addr[0] = offset >> 8;		/* block number */
85 	addr[1] = blk_off;		/* block offset */
86 	alen = 2;
87 #else
88 	addr[0] = offset >> 16;		/* block number */
89 	addr[1] = offset >>  8;		/* upper address octet */
90 	addr[2] = blk_off;		/* lower address octet */
91 	alen = 3;
92 #endif	/* CONFIG_SYS_I2C_EEPROM_ADDR_LEN */
93 
94 	addr[0] |= dev_addr;		/* insert device address */
95 
96 	return alen;
97 }
98 
99 static int eeprom_len(unsigned offset, unsigned end)
100 {
101 	unsigned len = end - offset;
102 
103 	/*
104 	 * For a FRAM device there is no limit on the number of the
105 	 * bytes that can be ccessed with the single read or write
106 	 * operation.
107 	 */
108 #if !defined(CONFIG_SYS_I2C_FRAM)
109 	unsigned blk_off = offset & 0xff;
110 	unsigned maxlen = EEPROM_PAGE_SIZE - EEPROM_PAGE_OFFSET(blk_off);
111 
112 	if (maxlen > I2C_RXTX_LEN)
113 		maxlen = I2C_RXTX_LEN;
114 
115 	if (len > maxlen)
116 		len = maxlen;
117 #endif
118 
119 	return len;
120 }
121 
122 static int eeprom_rw_block(unsigned offset, uchar *addr, unsigned alen,
123 			   uchar *buffer, unsigned len, bool read)
124 {
125 	int ret = 0;
126 
127 #if defined(CONFIG_DM_I2C) && defined(CONFIG_SYS_I2C_EEPROM_BUS)
128 	struct udevice *dev;
129 
130 	ret = i2c_get_chip_for_busnum(CONFIG_SYS_I2C_EEPROM_BUS, addr[0],
131 				      alen - 1, &dev);
132 	if (ret) {
133 		printf("%s: Cannot find udev for a bus %d\n", __func__,
134 		       CONFIG_SYS_I2C_EEPROM_BUS);
135 		return CMD_RET_FAILURE;
136 	}
137 
138 	if (read)
139 		ret = dm_i2c_read(dev, offset, buffer, len);
140 	else
141 		ret = dm_i2c_write(dev, offset, buffer, len);
142 
143 #else /* Non DM I2C support - will be removed */
144 #if defined(CONFIG_SYS_I2C_EEPROM_BUS)
145 	i2c_set_bus_num(CONFIG_SYS_I2C_EEPROM_BUS);
146 #endif
147 
148 	if (read)
149 		ret = i2c_read(addr[0], offset, alen - 1, buffer, len);
150 	else
151 		ret = i2c_write(addr[0], offset, alen - 1, buffer, len);
152 #endif /* CONFIG_DM_I2C && CONFIG_SYS_I2C_EEPROM_BUS */
153 	if (ret)
154 		ret = CMD_RET_FAILURE;
155 
156 	return ret;
157 }
158 
159 static int eeprom_rw(unsigned dev_addr, unsigned offset, uchar *buffer,
160 		     unsigned cnt, bool read)
161 {
162 	unsigned end = offset + cnt;
163 	unsigned alen, len;
164 	int rcode = 0;
165 	uchar addr[3];
166 
167 	while (offset < end) {
168 		alen = eeprom_addr(dev_addr, offset, addr);
169 
170 		len = eeprom_len(offset, end);
171 
172 		rcode = eeprom_rw_block(offset, addr, alen, buffer, len, read);
173 
174 		buffer += len;
175 		offset += len;
176 
177 		if (!read)
178 			udelay(CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS * 1000);
179 	}
180 
181 	return rcode;
182 }
183 
184 int eeprom_read(unsigned dev_addr, unsigned offset, uchar *buffer, unsigned cnt)
185 {
186 	/*
187 	 * Read data until done or would cross a page boundary.
188 	 * We must write the address again when changing pages
189 	 * because the next page may be in a different device.
190 	 */
191 	return eeprom_rw(dev_addr, offset, buffer, cnt, 1);
192 }
193 
194 int eeprom_write(unsigned dev_addr, unsigned offset,
195 		 uchar *buffer, unsigned cnt)
196 {
197 	int ret;
198 
199 	eeprom_write_enable(dev_addr, 1);
200 
201 	/*
202 	 * Write data until done or would cross a write page boundary.
203 	 * We must write the address again when changing pages
204 	 * because the address counter only increments within a page.
205 	 */
206 	ret = eeprom_rw(dev_addr, offset, buffer, cnt, 0);
207 
208 	eeprom_write_enable(dev_addr, 0);
209 	return ret;
210 }
211 
212 static int parse_numeric_param(char *str)
213 {
214 	char *endptr;
215 	int value = simple_strtol(str, &endptr, 16);
216 
217 	return (*endptr != '\0') ? -1 : value;
218 }
219 
220 /**
221  * parse_i2c_bus_addr - parse the i2c bus and i2c devaddr parameters
222  *
223  * @i2c_bus:	address to store the i2c bus
224  * @i2c_addr:	address to store the device i2c address
225  * @argc:	count of command line arguments left to parse
226  * @argv:	command line arguments left to parse
227  * @argc_no_bus_addr:	argc value we expect to see when bus & addr aren't given
228  *
229  * @returns:	number of arguments parsed or CMD_RET_USAGE if error
230  */
231 static int parse_i2c_bus_addr(int *i2c_bus, ulong *i2c_addr, int argc,
232 			      char * const argv[], int argc_no_bus_addr)
233 {
234 	int argc_no_bus = argc_no_bus_addr + 1;
235 	int argc_bus_addr = argc_no_bus_addr + 2;
236 
237 #ifdef CONFIG_SYS_DEF_EEPROM_ADDR
238 	if (argc == argc_no_bus_addr) {
239 		*i2c_bus = -1;
240 		*i2c_addr = CONFIG_SYS_DEF_EEPROM_ADDR;
241 
242 		return 0;
243 	}
244 #endif
245 	if (argc == argc_no_bus) {
246 		*i2c_bus = -1;
247 		*i2c_addr = parse_numeric_param(argv[0]);
248 
249 		return 1;
250 	}
251 
252 	if (argc == argc_bus_addr) {
253 		*i2c_bus = parse_numeric_param(argv[0]);
254 		*i2c_addr = parse_numeric_param(argv[1]);
255 
256 		return 2;
257 	}
258 
259 	return CMD_RET_USAGE;
260 }
261 
262 #ifdef CONFIG_CMD_EEPROM_LAYOUT
263 
264 __weak int eeprom_parse_layout_version(char *str)
265 {
266 	return LAYOUT_VERSION_UNRECOGNIZED;
267 }
268 
269 static unsigned char eeprom_buf[CONFIG_SYS_EEPROM_SIZE];
270 
271 #endif
272 
273 enum eeprom_action {
274 	EEPROM_READ,
275 	EEPROM_WRITE,
276 	EEPROM_PRINT,
277 	EEPROM_UPDATE,
278 	EEPROM_ACTION_INVALID,
279 };
280 
281 static enum eeprom_action parse_action(char *cmd)
282 {
283 	if (!strncmp(cmd, "read", 4))
284 		return EEPROM_READ;
285 	if (!strncmp(cmd, "write", 5))
286 		return EEPROM_WRITE;
287 #ifdef CONFIG_CMD_EEPROM_LAYOUT
288 	if (!strncmp(cmd, "print", 5))
289 		return EEPROM_PRINT;
290 	if (!strncmp(cmd, "update", 6))
291 		return EEPROM_UPDATE;
292 #endif
293 
294 	return EEPROM_ACTION_INVALID;
295 }
296 
297 static int eeprom_execute_command(enum eeprom_action action, int i2c_bus,
298 				  ulong i2c_addr, int layout_ver, char *key,
299 				  char *value, ulong addr, ulong off, ulong cnt)
300 {
301 	int rcode = 0;
302 	const char *const fmt =
303 		"\nEEPROM @0x%lX %s: addr %08lx  off %04lx  count %ld ... ";
304 #ifdef CONFIG_CMD_EEPROM_LAYOUT
305 	struct eeprom_layout layout;
306 #endif
307 
308 	if (action == EEPROM_ACTION_INVALID)
309 		return CMD_RET_USAGE;
310 
311 	eeprom_init(i2c_bus);
312 	if (action == EEPROM_READ) {
313 		printf(fmt, i2c_addr, "read", addr, off, cnt);
314 
315 		rcode = eeprom_read(i2c_addr, off, (uchar *)addr, cnt);
316 
317 		puts("done\n");
318 		return rcode;
319 	} else if (action == EEPROM_WRITE) {
320 		printf(fmt, i2c_addr, "write", addr, off, cnt);
321 
322 		rcode = eeprom_write(i2c_addr, off, (uchar *)addr, cnt);
323 
324 		puts("done\n");
325 		return rcode;
326 	}
327 
328 #ifdef CONFIG_CMD_EEPROM_LAYOUT
329 	rcode = eeprom_read(i2c_addr, 0, eeprom_buf, CONFIG_SYS_EEPROM_SIZE);
330 	if (rcode < 0)
331 		return rcode;
332 
333 	eeprom_layout_setup(&layout, eeprom_buf, CONFIG_SYS_EEPROM_SIZE,
334 			    layout_ver);
335 
336 	if (action == EEPROM_PRINT) {
337 		layout.print(&layout);
338 		return 0;
339 	}
340 
341 	layout.update(&layout, key, value);
342 
343 	rcode = eeprom_write(i2c_addr, 0, layout.data, CONFIG_SYS_EEPROM_SIZE);
344 #endif
345 
346 	return rcode;
347 }
348 
349 #define NEXT_PARAM(argc, index)	{ (argc)--; (index)++; }
350 int do_eeprom(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
351 {
352 	int layout_ver = LAYOUT_VERSION_AUTODETECT;
353 	enum eeprom_action action = EEPROM_ACTION_INVALID;
354 	int i2c_bus = -1, index = 0;
355 	ulong i2c_addr = -1, addr = 0, cnt = 0, off = 0;
356 	int ret;
357 	char *field_name = "";
358 	char *field_value = "";
359 
360 	if (argc <= 1)
361 		return CMD_RET_USAGE;
362 
363 	NEXT_PARAM(argc, index); /* Skip program name */
364 
365 	action = parse_action(argv[index]);
366 	NEXT_PARAM(argc, index);
367 
368 	if (action == EEPROM_ACTION_INVALID)
369 		return CMD_RET_USAGE;
370 
371 #ifdef CONFIG_CMD_EEPROM_LAYOUT
372 	if (action == EEPROM_PRINT || action == EEPROM_UPDATE) {
373 		if (!strcmp(argv[index], "-l")) {
374 			NEXT_PARAM(argc, index);
375 			layout_ver = eeprom_parse_layout_version(argv[index]);
376 			NEXT_PARAM(argc, index);
377 		}
378 	}
379 #endif
380 
381 	switch (action) {
382 	case EEPROM_READ:
383 	case EEPROM_WRITE:
384 		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
385 					 argv + index, 3);
386 		break;
387 	case EEPROM_PRINT:
388 		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
389 					 argv + index, 0);
390 		break;
391 	case EEPROM_UPDATE:
392 		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
393 					 argv + index, 2);
394 		break;
395 	default:
396 		/* Get compiler to stop whining */
397 		return CMD_RET_USAGE;
398 	}
399 
400 	if (ret == CMD_RET_USAGE)
401 		return ret;
402 
403 	while (ret--)
404 		NEXT_PARAM(argc, index);
405 
406 	if (action == EEPROM_READ || action == EEPROM_WRITE) {
407 		addr = parse_numeric_param(argv[index]);
408 		NEXT_PARAM(argc, index);
409 		off = parse_numeric_param(argv[index]);
410 		NEXT_PARAM(argc, index);
411 		cnt = parse_numeric_param(argv[index]);
412 	}
413 
414 #ifdef CONFIG_CMD_EEPROM_LAYOUT
415 	if (action == EEPROM_UPDATE) {
416 		field_name = argv[index];
417 		NEXT_PARAM(argc, index);
418 		field_value = argv[index];
419 		NEXT_PARAM(argc, index);
420 	}
421 #endif
422 
423 	return eeprom_execute_command(action, i2c_bus, i2c_addr, layout_ver,
424 				      field_name, field_value, addr, off, cnt);
425 }
426 
427 U_BOOT_CMD(
428 	eeprom,	8,	1,	do_eeprom,
429 	"EEPROM sub-system",
430 	"read  <bus> <devaddr> addr off cnt\n"
431 	"eeprom write <bus> <devaddr> addr off cnt\n"
432 	"       - read/write `cnt' bytes from `devaddr` EEPROM at offset `off'"
433 #ifdef CONFIG_CMD_EEPROM_LAYOUT
434 	"\n"
435 	"eeprom print [-l <layout_version>] <bus> <devaddr>\n"
436 	"       - Print layout fields and their data in human readable format\n"
437 	"eeprom update [-l <layout_version>] <bus> <devaddr> field_name field_value\n"
438 	"       - Update a specific eeprom field with new data.\n"
439 	"         The new data must be written in the same human readable format as shown by the print command.\n"
440 	"\n"
441 	"LAYOUT VERSIONS\n"
442 	"The -l option can be used to force the command to interpret the EEPROM data using the chosen layout.\n"
443 	"If the -l option is omitted, the command will auto detect the layout based on the data in the EEPROM.\n"
444 	"The values which can be provided with the -l option are:\n"
445 	CONFIG_EEPROM_LAYOUT_HELP_STRING"\n"
446 #endif
447 )
448