xref: /openbmc/u-boot/cmd/eeprom.c (revision b6cba297)
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 	/* SPI EEPROM */
70 #if defined(CONFIG_MPC8XX_SPI) && !defined(CONFIG_ENV_EEPROM_IS_ON_I2C)
71 	spi_init_f();
72 #endif
73 
74 	/* I2C EEPROM */
75 #if defined(CONFIG_SYS_I2C)
76 	if (bus >= 0)
77 		i2c_set_bus_num(bus);
78 	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
79 #endif
80 }
81 
82 static int eeprom_addr(unsigned dev_addr, unsigned offset, uchar *addr)
83 {
84 	unsigned blk_off;
85 	int alen;
86 
87 	blk_off = offset & 0xff;	/* block offset */
88 #if CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1
89 	addr[0] = offset >> 8;		/* block number */
90 	addr[1] = blk_off;		/* block offset */
91 	alen = 2;
92 #else
93 	addr[0] = offset >> 16;		/* block number */
94 	addr[1] = offset >>  8;		/* upper address octet */
95 	addr[2] = blk_off;		/* lower address octet */
96 	alen = 3;
97 #endif	/* CONFIG_SYS_I2C_EEPROM_ADDR_LEN */
98 
99 	addr[0] |= dev_addr;		/* insert device address */
100 
101 	return alen;
102 }
103 
104 static int eeprom_len(unsigned offset, unsigned end)
105 {
106 	unsigned len = end - offset;
107 
108 	/*
109 	 * For a FRAM device there is no limit on the number of the
110 	 * bytes that can be ccessed with the single read or write
111 	 * operation.
112 	 */
113 #if !defined(CONFIG_SYS_I2C_FRAM)
114 	unsigned blk_off = offset & 0xff;
115 	unsigned maxlen = EEPROM_PAGE_SIZE - EEPROM_PAGE_OFFSET(blk_off);
116 
117 	if (maxlen > I2C_RXTX_LEN)
118 		maxlen = I2C_RXTX_LEN;
119 
120 	if (len > maxlen)
121 		len = maxlen;
122 #endif
123 
124 	return len;
125 }
126 
127 static int eeprom_rw_block(unsigned offset, uchar *addr, unsigned alen,
128 			   uchar *buffer, unsigned len, bool read)
129 {
130 	int ret = 0;
131 
132 	/* SPI */
133 #if defined(CONFIG_MPC8XX_SPI) && !defined(CONFIG_ENV_EEPROM_IS_ON_I2C)
134 	if (read)
135 		spi_read(addr, alen, buffer, len);
136 	else
137 		spi_write(addr, alen, buffer, len);
138 #else	/* I2C */
139 
140 #if defined(CONFIG_DM_I2C) && defined(CONFIG_SYS_I2C_EEPROM_BUS)
141 	struct udevice *dev;
142 
143 	ret = i2c_get_chip_for_busnum(CONFIG_SYS_I2C_EEPROM_BUS, addr[0],
144 				      alen - 1, &dev);
145 	if (ret) {
146 		printf("%s: Cannot find udev for a bus %d\n", __func__,
147 		       CONFIG_SYS_I2C_EEPROM_BUS);
148 		return CMD_RET_FAILURE;
149 	}
150 
151 	if (read)
152 		ret = dm_i2c_read(dev, offset, buffer, len);
153 	else
154 		ret = dm_i2c_write(dev, offset, buffer, len);
155 
156 #else /* Non DM I2C support - will be removed */
157 #if defined(CONFIG_SYS_I2C_EEPROM_BUS)
158 	i2c_set_bus_num(CONFIG_SYS_I2C_EEPROM_BUS);
159 #endif
160 
161 	if (read)
162 		ret = i2c_read(addr[0], offset, alen - 1, buffer, len);
163 	else
164 		ret = i2c_write(addr[0], offset, alen - 1, buffer, len);
165 #endif
166 #endif /* CONFIG_DM_I2C && CONFIG_SYS_I2C_EEPROM_BUS */
167 	if (ret)
168 		ret = CMD_RET_FAILURE;
169 
170 	return ret;
171 }
172 
173 static int eeprom_rw(unsigned dev_addr, unsigned offset, uchar *buffer,
174 		     unsigned cnt, bool read)
175 {
176 	unsigned end = offset + cnt;
177 	unsigned alen, len;
178 	int rcode = 0;
179 	uchar addr[3];
180 
181 	while (offset < end) {
182 		alen = eeprom_addr(dev_addr, offset, addr);
183 
184 		len = eeprom_len(offset, end);
185 
186 		rcode = eeprom_rw_block(offset, addr, alen, buffer, len, read);
187 
188 		buffer += len;
189 		offset += len;
190 
191 		if (!read)
192 			udelay(CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS * 1000);
193 	}
194 
195 	return rcode;
196 }
197 
198 int eeprom_read(unsigned dev_addr, unsigned offset, uchar *buffer, unsigned cnt)
199 {
200 	/*
201 	 * Read data until done or would cross a page boundary.
202 	 * We must write the address again when changing pages
203 	 * because the next page may be in a different device.
204 	 */
205 	return eeprom_rw(dev_addr, offset, buffer, cnt, 1);
206 }
207 
208 int eeprom_write(unsigned dev_addr, unsigned offset,
209 		 uchar *buffer, unsigned cnt)
210 {
211 	int ret;
212 
213 	eeprom_write_enable(dev_addr, 1);
214 
215 	/*
216 	 * Write data until done or would cross a write page boundary.
217 	 * We must write the address again when changing pages
218 	 * because the address counter only increments within a page.
219 	 */
220 	ret = eeprom_rw(dev_addr, offset, buffer, cnt, 0);
221 
222 	eeprom_write_enable(dev_addr, 0);
223 	return ret;
224 }
225 
226 static int parse_numeric_param(char *str)
227 {
228 	char *endptr;
229 	int value = simple_strtol(str, &endptr, 16);
230 
231 	return (*endptr != '\0') ? -1 : value;
232 }
233 
234 /**
235  * parse_i2c_bus_addr - parse the i2c bus and i2c devaddr parameters
236  *
237  * @i2c_bus:	address to store the i2c bus
238  * @i2c_addr:	address to store the device i2c address
239  * @argc:	count of command line arguments left to parse
240  * @argv:	command line arguments left to parse
241  * @argc_no_bus_addr:	argc value we expect to see when bus & addr aren't given
242  *
243  * @returns:	number of arguments parsed or CMD_RET_USAGE if error
244  */
245 static int parse_i2c_bus_addr(int *i2c_bus, ulong *i2c_addr, int argc,
246 			      char * const argv[], int argc_no_bus_addr)
247 {
248 	int argc_no_bus = argc_no_bus_addr + 1;
249 	int argc_bus_addr = argc_no_bus_addr + 2;
250 
251 #ifdef CONFIG_SYS_DEF_EEPROM_ADDR
252 	if (argc == argc_no_bus_addr) {
253 		*i2c_bus = -1;
254 		*i2c_addr = CONFIG_SYS_DEF_EEPROM_ADDR;
255 
256 		return 0;
257 	}
258 #endif
259 	if (argc == argc_no_bus) {
260 		*i2c_bus = -1;
261 		*i2c_addr = parse_numeric_param(argv[0]);
262 
263 		return 1;
264 	}
265 
266 	if (argc == argc_bus_addr) {
267 		*i2c_bus = parse_numeric_param(argv[0]);
268 		*i2c_addr = parse_numeric_param(argv[1]);
269 
270 		return 2;
271 	}
272 
273 	return CMD_RET_USAGE;
274 }
275 
276 #ifdef CONFIG_CMD_EEPROM_LAYOUT
277 
278 __weak int eeprom_parse_layout_version(char *str)
279 {
280 	return LAYOUT_VERSION_UNRECOGNIZED;
281 }
282 
283 static unsigned char eeprom_buf[CONFIG_SYS_EEPROM_SIZE];
284 
285 #endif
286 
287 enum eeprom_action {
288 	EEPROM_READ,
289 	EEPROM_WRITE,
290 	EEPROM_PRINT,
291 	EEPROM_UPDATE,
292 	EEPROM_ACTION_INVALID,
293 };
294 
295 static enum eeprom_action parse_action(char *cmd)
296 {
297 	if (!strncmp(cmd, "read", 4))
298 		return EEPROM_READ;
299 	if (!strncmp(cmd, "write", 5))
300 		return EEPROM_WRITE;
301 #ifdef CONFIG_CMD_EEPROM_LAYOUT
302 	if (!strncmp(cmd, "print", 5))
303 		return EEPROM_PRINT;
304 	if (!strncmp(cmd, "update", 6))
305 		return EEPROM_UPDATE;
306 #endif
307 
308 	return EEPROM_ACTION_INVALID;
309 }
310 
311 static int eeprom_execute_command(enum eeprom_action action, int i2c_bus,
312 				  ulong i2c_addr, int layout_ver, char *key,
313 				  char *value, ulong addr, ulong off, ulong cnt)
314 {
315 	int rcode = 0;
316 	const char *const fmt =
317 		"\nEEPROM @0x%lX %s: addr %08lx  off %04lx  count %ld ... ";
318 #ifdef CONFIG_CMD_EEPROM_LAYOUT
319 	struct eeprom_layout layout;
320 #endif
321 
322 	if (action == EEPROM_ACTION_INVALID)
323 		return CMD_RET_USAGE;
324 
325 	eeprom_init(i2c_bus);
326 	if (action == EEPROM_READ) {
327 		printf(fmt, i2c_addr, "read", addr, off, cnt);
328 
329 		rcode = eeprom_read(i2c_addr, off, (uchar *)addr, cnt);
330 
331 		puts("done\n");
332 		return rcode;
333 	} else if (action == EEPROM_WRITE) {
334 		printf(fmt, i2c_addr, "write", addr, off, cnt);
335 
336 		rcode = eeprom_write(i2c_addr, off, (uchar *)addr, cnt);
337 
338 		puts("done\n");
339 		return rcode;
340 	}
341 
342 #ifdef CONFIG_CMD_EEPROM_LAYOUT
343 	rcode = eeprom_read(i2c_addr, 0, eeprom_buf, CONFIG_SYS_EEPROM_SIZE);
344 	if (rcode < 0)
345 		return rcode;
346 
347 	eeprom_layout_setup(&layout, eeprom_buf, CONFIG_SYS_EEPROM_SIZE,
348 			    layout_ver);
349 
350 	if (action == EEPROM_PRINT) {
351 		layout.print(&layout);
352 		return 0;
353 	}
354 
355 	layout.update(&layout, key, value);
356 
357 	rcode = eeprom_write(i2c_addr, 0, layout.data, CONFIG_SYS_EEPROM_SIZE);
358 #endif
359 
360 	return rcode;
361 }
362 
363 #define NEXT_PARAM(argc, index)	{ (argc)--; (index)++; }
364 int do_eeprom(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
365 {
366 	int layout_ver = LAYOUT_VERSION_AUTODETECT;
367 	enum eeprom_action action = EEPROM_ACTION_INVALID;
368 	int i2c_bus = -1, index = 0;
369 	ulong i2c_addr = -1, addr = 0, cnt = 0, off = 0;
370 	int ret;
371 	char *field_name = "";
372 	char *field_value = "";
373 
374 	if (argc <= 1)
375 		return CMD_RET_USAGE;
376 
377 	NEXT_PARAM(argc, index); /* Skip program name */
378 
379 	action = parse_action(argv[index]);
380 	NEXT_PARAM(argc, index);
381 
382 	if (action == EEPROM_ACTION_INVALID)
383 		return CMD_RET_USAGE;
384 
385 #ifdef CONFIG_CMD_EEPROM_LAYOUT
386 	if (action == EEPROM_PRINT || action == EEPROM_UPDATE) {
387 		if (!strcmp(argv[index], "-l")) {
388 			NEXT_PARAM(argc, index);
389 			layout_ver = eeprom_parse_layout_version(argv[index]);
390 			NEXT_PARAM(argc, index);
391 		}
392 	}
393 #endif
394 
395 	switch (action) {
396 	case EEPROM_READ:
397 	case EEPROM_WRITE:
398 		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
399 					 argv + index, 3);
400 		break;
401 	case EEPROM_PRINT:
402 		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
403 					 argv + index, 0);
404 		break;
405 	case EEPROM_UPDATE:
406 		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
407 					 argv + index, 2);
408 		break;
409 	default:
410 		/* Get compiler to stop whining */
411 		return CMD_RET_USAGE;
412 	}
413 
414 	if (ret == CMD_RET_USAGE)
415 		return ret;
416 
417 	while (ret--)
418 		NEXT_PARAM(argc, index);
419 
420 	if (action == EEPROM_READ || action == EEPROM_WRITE) {
421 		addr = parse_numeric_param(argv[index]);
422 		NEXT_PARAM(argc, index);
423 		off = parse_numeric_param(argv[index]);
424 		NEXT_PARAM(argc, index);
425 		cnt = parse_numeric_param(argv[index]);
426 	}
427 
428 #ifdef CONFIG_CMD_EEPROM_LAYOUT
429 	if (action == EEPROM_UPDATE) {
430 		field_name = argv[index];
431 		NEXT_PARAM(argc, index);
432 		field_value = argv[index];
433 		NEXT_PARAM(argc, index);
434 	}
435 #endif
436 
437 	return eeprom_execute_command(action, i2c_bus, i2c_addr, layout_ver,
438 				      field_name, field_value, addr, off, cnt);
439 }
440 
441 U_BOOT_CMD(
442 	eeprom,	8,	1,	do_eeprom,
443 	"EEPROM sub-system",
444 	"read  <bus> <devaddr> addr off cnt\n"
445 	"eeprom write <bus> <devaddr> addr off cnt\n"
446 	"       - read/write `cnt' bytes from `devaddr` EEPROM at offset `off'"
447 #ifdef CONFIG_CMD_EEPROM_LAYOUT
448 	"\n"
449 	"eeprom print [-l <layout_version>] <bus> <devaddr>\n"
450 	"       - Print layout fields and their data in human readable format\n"
451 	"eeprom update [-l <layout_version>] <bus> <devaddr> field_name field_value\n"
452 	"       - Update a specific eeprom field with new data.\n"
453 	"         The new data must be written in the same human readable format as shown by the print command.\n"
454 	"\n"
455 	"LAYOUT VERSIONS\n"
456 	"The -l option can be used to force the command to interpret the EEPROM data using the chosen layout.\n"
457 	"If the -l option is omitted, the command will auto detect the layout based on the data in the EEPROM.\n"
458 	"The values which can be provided with the -l option are:\n"
459 	CONFIG_EEPROM_LAYOUT_HELP_STRING"\n"
460 #endif
461 )
462