xref: /openbmc/u-boot/cmd/eeprom.c (revision e8645527)
1 /*
2  * (C) Copyright 2000, 2001
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 /*
9  * Support for read and write access to EEPROM like memory devices. This
10  * includes regular EEPROM as well as  FRAM (ferroelectic nonvolaile RAM).
11  * FRAM devices read and write data at bus speed. In particular, there is no
12  * write delay. Also, there is no limit imposed on the number of bytes that can
13  * be transferred with a single read or write.
14  *
15  * Use the following configuration options to ensure no unneeded performance
16  * degradation (typical for EEPROM) is incured for FRAM memory:
17  *
18  * #define CONFIG_SYS_I2C_FRAM
19  * #undef CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS
20  *
21  */
22 
23 #include <common.h>
24 #include <config.h>
25 #include <command.h>
26 #include <i2c.h>
27 #include <eeprom_layout.h>
28 
29 #ifndef	CONFIG_SYS_I2C_SPEED
30 #define	CONFIG_SYS_I2C_SPEED	50000
31 #endif
32 
33 #ifndef CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS
34 #define CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS	0
35 #endif
36 
37 #ifndef CONFIG_SYS_EEPROM_PAGE_WRITE_BITS
38 #define CONFIG_SYS_EEPROM_PAGE_WRITE_BITS	8
39 #endif
40 
41 #ifndef	I2C_RXTX_LEN
42 #define I2C_RXTX_LEN	128
43 #endif
44 
45 #define	EEPROM_PAGE_SIZE	(1 << CONFIG_SYS_EEPROM_PAGE_WRITE_BITS)
46 #define	EEPROM_PAGE_OFFSET(x)	((x) & (EEPROM_PAGE_SIZE - 1))
47 
48 /*
49  * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 2 (16-bit EEPROM address) offset is
50  *   0x000nxxxx for EEPROM address selectors at n, offset xxxx in EEPROM.
51  *
52  * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1 (8-bit EEPROM page address) offset is
53  *   0x00000nxx for EEPROM address selectors and page number at n.
54  */
55 #if !defined(CONFIG_SPI) || defined(CONFIG_ENV_EEPROM_IS_ON_I2C)
56 #if !defined(CONFIG_SYS_I2C_EEPROM_ADDR_LEN) || \
57 	(CONFIG_SYS_I2C_EEPROM_ADDR_LEN < 1) || \
58 	(CONFIG_SYS_I2C_EEPROM_ADDR_LEN > 2)
59 #error CONFIG_SYS_I2C_EEPROM_ADDR_LEN must be 1 or 2
60 #endif
61 #endif
62 
63 __weak int eeprom_write_enable(unsigned dev_addr, int state)
64 {
65 	return 0;
66 }
67 
68 void eeprom_init(int bus)
69 {
70 	/* SPI EEPROM */
71 #if defined(CONFIG_SPI) && !defined(CONFIG_ENV_EEPROM_IS_ON_I2C)
72 	spi_init_f();
73 #endif
74 
75 	/* I2C EEPROM */
76 #if defined(CONFIG_SYS_I2C)
77 	if (bus >= 0)
78 		i2c_set_bus_num(bus);
79 	i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
80 #endif
81 }
82 
83 static int eeprom_addr(unsigned dev_addr, unsigned offset, uchar *addr)
84 {
85 	unsigned blk_off;
86 	int alen;
87 
88 	blk_off = offset & 0xff;	/* block offset */
89 #if CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1
90 	addr[0] = offset >> 8;		/* block number */
91 	addr[1] = blk_off;		/* block offset */
92 	alen = 2;
93 #else
94 	addr[0] = offset >> 16;		/* block number */
95 	addr[1] = offset >>  8;		/* upper address octet */
96 	addr[2] = blk_off;		/* lower address octet */
97 	alen = 3;
98 #endif	/* CONFIG_SYS_I2C_EEPROM_ADDR_LEN */
99 
100 	addr[0] |= dev_addr;		/* insert device address */
101 
102 	return alen;
103 }
104 
105 static int eeprom_len(unsigned offset, unsigned end)
106 {
107 	unsigned len = end - offset;
108 
109 	/*
110 	 * For a FRAM device there is no limit on the number of the
111 	 * bytes that can be ccessed with the single read or write
112 	 * operation.
113 	 */
114 #if !defined(CONFIG_SYS_I2C_FRAM)
115 	unsigned blk_off = offset & 0xff;
116 	unsigned maxlen = EEPROM_PAGE_SIZE - EEPROM_PAGE_OFFSET(blk_off);
117 
118 	if (maxlen > I2C_RXTX_LEN)
119 		maxlen = I2C_RXTX_LEN;
120 
121 	if (len > maxlen)
122 		len = maxlen;
123 #endif
124 
125 	return len;
126 }
127 
128 static int eeprom_rw_block(unsigned offset, uchar *addr, unsigned alen,
129 			   uchar *buffer, unsigned len, bool read)
130 {
131 	int ret = 0;
132 
133 	/* SPI */
134 #if defined(CONFIG_SPI) && !defined(CONFIG_ENV_EEPROM_IS_ON_I2C)
135 	if (read)
136 		spi_read(addr, alen, buffer, len);
137 	else
138 		spi_write(addr, alen, buffer, len);
139 #else	/* I2C */
140 
141 #if defined(CONFIG_SYS_I2C_EEPROM_BUS)
142 	i2c_set_bus_num(CONFIG_SYS_I2C_EEPROM_BUS);
143 #endif
144 
145 	if (read)
146 		ret = i2c_read(addr[0], offset, alen - 1, buffer, len);
147 	else
148 		ret = i2c_write(addr[0], offset, alen - 1, buffer, len);
149 
150 	if (ret)
151 		ret = 1;
152 #endif
153 	return ret;
154 }
155 
156 static int eeprom_rw(unsigned dev_addr, unsigned offset, uchar *buffer,
157 		     unsigned cnt, bool read)
158 {
159 	unsigned end = offset + cnt;
160 	unsigned alen, len;
161 	int rcode = 0;
162 	uchar addr[3];
163 
164 	while (offset < end) {
165 		alen = eeprom_addr(dev_addr, offset, addr);
166 
167 		len = eeprom_len(offset, end);
168 
169 		rcode = eeprom_rw_block(offset, addr, alen, buffer, len, read);
170 
171 		buffer += len;
172 		offset += len;
173 
174 		if (!read)
175 			udelay(CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS * 1000);
176 	}
177 
178 	return rcode;
179 }
180 
181 int eeprom_read(unsigned dev_addr, unsigned offset, uchar *buffer, unsigned cnt)
182 {
183 	/*
184 	 * Read data until done or would cross a page boundary.
185 	 * We must write the address again when changing pages
186 	 * because the next page may be in a different device.
187 	 */
188 	return eeprom_rw(dev_addr, offset, buffer, cnt, 1);
189 }
190 
191 int eeprom_write(unsigned dev_addr, unsigned offset,
192 		 uchar *buffer, unsigned cnt)
193 {
194 	int ret;
195 
196 	eeprom_write_enable(dev_addr, 1);
197 
198 	/*
199 	 * Write data until done or would cross a write page boundary.
200 	 * We must write the address again when changing pages
201 	 * because the address counter only increments within a page.
202 	 */
203 	ret = eeprom_rw(dev_addr, offset, buffer, cnt, 0);
204 
205 	eeprom_write_enable(dev_addr, 0);
206 	return ret;
207 }
208 
209 static int parse_numeric_param(char *str)
210 {
211 	char *endptr;
212 	int value = simple_strtol(str, &endptr, 16);
213 
214 	return (*endptr != '\0') ? -1 : value;
215 }
216 
217 /**
218  * parse_i2c_bus_addr - parse the i2c bus and i2c devaddr parameters
219  *
220  * @i2c_bus:	address to store the i2c bus
221  * @i2c_addr:	address to store the device i2c address
222  * @argc:	count of command line arguments left to parse
223  * @argv:	command line arguments left to parse
224  * @argc_no_bus_addr:	argc value we expect to see when bus & addr aren't given
225  *
226  * @returns:	number of arguments parsed or CMD_RET_USAGE if error
227  */
228 static int parse_i2c_bus_addr(int *i2c_bus, ulong *i2c_addr, int argc,
229 			      char * const argv[], int argc_no_bus_addr)
230 {
231 	int argc_no_bus = argc_no_bus_addr + 1;
232 	int argc_bus_addr = argc_no_bus_addr + 2;
233 
234 #ifdef CONFIG_SYS_DEF_EEPROM_ADDR
235 	if (argc == argc_no_bus_addr) {
236 		*i2c_bus = -1;
237 		*i2c_addr = CONFIG_SYS_DEF_EEPROM_ADDR;
238 
239 		return 0;
240 	}
241 #endif
242 	if (argc == argc_no_bus) {
243 		*i2c_bus = -1;
244 		*i2c_addr = parse_numeric_param(argv[0]);
245 
246 		return 1;
247 	}
248 
249 	if (argc == argc_bus_addr) {
250 		*i2c_bus = parse_numeric_param(argv[0]);
251 		*i2c_addr = parse_numeric_param(argv[1]);
252 
253 		return 2;
254 	}
255 
256 	return CMD_RET_USAGE;
257 }
258 
259 #ifdef CONFIG_CMD_EEPROM_LAYOUT
260 
261 __weak int eeprom_parse_layout_version(char *str)
262 {
263 	return LAYOUT_VERSION_UNRECOGNIZED;
264 }
265 
266 static unsigned char eeprom_buf[CONFIG_SYS_EEPROM_SIZE];
267 
268 #endif
269 
270 enum eeprom_action {
271 	EEPROM_READ,
272 	EEPROM_WRITE,
273 	EEPROM_PRINT,
274 	EEPROM_UPDATE,
275 	EEPROM_ACTION_INVALID,
276 };
277 
278 static enum eeprom_action parse_action(char *cmd)
279 {
280 	if (!strncmp(cmd, "read", 4))
281 		return EEPROM_READ;
282 	if (!strncmp(cmd, "write", 5))
283 		return EEPROM_WRITE;
284 #ifdef CONFIG_CMD_EEPROM_LAYOUT
285 	if (!strncmp(cmd, "print", 5))
286 		return EEPROM_PRINT;
287 	if (!strncmp(cmd, "update", 6))
288 		return EEPROM_UPDATE;
289 #endif
290 
291 	return EEPROM_ACTION_INVALID;
292 }
293 
294 static int eeprom_execute_command(enum eeprom_action action, int i2c_bus,
295 				  ulong i2c_addr, int layout_ver, char *key,
296 				  char *value, ulong addr, ulong off, ulong cnt)
297 {
298 	int rcode = 0;
299 	const char *const fmt =
300 		"\nEEPROM @0x%lX %s: addr %08lx  off %04lx  count %ld ... ";
301 #ifdef CONFIG_CMD_EEPROM_LAYOUT
302 	struct eeprom_layout layout;
303 #endif
304 
305 	if (action == EEPROM_ACTION_INVALID)
306 		return CMD_RET_USAGE;
307 
308 	eeprom_init(i2c_bus);
309 	if (action == EEPROM_READ) {
310 		printf(fmt, i2c_addr, "read", addr, off, cnt);
311 
312 		rcode = eeprom_read(i2c_addr, off, (uchar *)addr, cnt);
313 
314 		puts("done\n");
315 		return rcode;
316 	} else if (action == EEPROM_WRITE) {
317 		printf(fmt, i2c_addr, "write", addr, off, cnt);
318 
319 		rcode = eeprom_write(i2c_addr, off, (uchar *)addr, cnt);
320 
321 		puts("done\n");
322 		return rcode;
323 	}
324 
325 #ifdef CONFIG_CMD_EEPROM_LAYOUT
326 	rcode = eeprom_read(i2c_addr, 0, eeprom_buf, CONFIG_SYS_EEPROM_SIZE);
327 	if (rcode < 0)
328 		return rcode;
329 
330 	eeprom_layout_setup(&layout, eeprom_buf, CONFIG_SYS_EEPROM_SIZE,
331 			    layout_ver);
332 
333 	if (action == EEPROM_PRINT) {
334 		layout.print(&layout);
335 		return 0;
336 	}
337 
338 	layout.update(&layout, key, value);
339 
340 	rcode = eeprom_write(i2c_addr, 0, layout.data, CONFIG_SYS_EEPROM_SIZE);
341 #endif
342 
343 	return rcode;
344 }
345 
346 #define NEXT_PARAM(argc, index)	{ (argc)--; (index)++; }
347 int do_eeprom(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
348 {
349 	int layout_ver = LAYOUT_VERSION_AUTODETECT;
350 	enum eeprom_action action = EEPROM_ACTION_INVALID;
351 	int i2c_bus = -1, index = 0;
352 	ulong i2c_addr = -1, addr = 0, cnt = 0, off = 0;
353 	int ret;
354 	char *field_name = "";
355 	char *field_value = "";
356 
357 	if (argc <= 1)
358 		return CMD_RET_USAGE;
359 
360 	NEXT_PARAM(argc, index); /* Skip program name */
361 
362 	action = parse_action(argv[index]);
363 	NEXT_PARAM(argc, index);
364 
365 	if (action == EEPROM_ACTION_INVALID)
366 		return CMD_RET_USAGE;
367 
368 #ifdef CONFIG_CMD_EEPROM_LAYOUT
369 	if (action == EEPROM_PRINT || action == EEPROM_UPDATE) {
370 		if (!strcmp(argv[index], "-l")) {
371 			NEXT_PARAM(argc, index);
372 			layout_ver = eeprom_parse_layout_version(argv[index]);
373 			NEXT_PARAM(argc, index);
374 		}
375 	}
376 #endif
377 
378 	switch (action) {
379 	case EEPROM_READ:
380 	case EEPROM_WRITE:
381 		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
382 					 argv + index, 3);
383 		break;
384 	case EEPROM_PRINT:
385 		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
386 					 argv + index, 0);
387 		break;
388 	case EEPROM_UPDATE:
389 		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
390 					 argv + index, 2);
391 		break;
392 	default:
393 		/* Get compiler to stop whining */
394 		return CMD_RET_USAGE;
395 	}
396 
397 	if (ret == CMD_RET_USAGE)
398 		return ret;
399 
400 	while (ret--)
401 		NEXT_PARAM(argc, index);
402 
403 	if (action == EEPROM_READ || action == EEPROM_WRITE) {
404 		addr = parse_numeric_param(argv[index]);
405 		NEXT_PARAM(argc, index);
406 		off = parse_numeric_param(argv[index]);
407 		NEXT_PARAM(argc, index);
408 		cnt = parse_numeric_param(argv[index]);
409 	}
410 
411 #ifdef CONFIG_CMD_EEPROM_LAYOUT
412 	if (action == EEPROM_UPDATE) {
413 		field_name = argv[index];
414 		NEXT_PARAM(argc, index);
415 		field_value = argv[index];
416 		NEXT_PARAM(argc, index);
417 	}
418 #endif
419 
420 	return eeprom_execute_command(action, i2c_bus, i2c_addr, layout_ver,
421 				      field_name, field_value, addr, off, cnt);
422 }
423 
424 U_BOOT_CMD(
425 	eeprom,	8,	1,	do_eeprom,
426 	"EEPROM sub-system",
427 	"read  <bus> <devaddr> addr off cnt\n"
428 	"eeprom write <bus> <devaddr> addr off cnt\n"
429 	"       - read/write `cnt' bytes from `devaddr` EEPROM at offset `off'"
430 #ifdef CONFIG_CMD_EEPROM_LAYOUT
431 	"\n"
432 	"eeprom print [-l <layout_version>] <bus> <devaddr>\n"
433 	"       - Print layout fields and their data in human readable format\n"
434 	"eeprom update [-l <layout_version>] <bus> <devaddr> field_name field_value\n"
435 	"       - Update a specific eeprom field with new data.\n"
436 	"         The new data must be written in the same human readable format as shown by the print command.\n"
437 	"\n"
438 	"LAYOUT VERSIONS\n"
439 	"The -l option can be used to force the command to interpret the EEPROM data using the chosen layout.\n"
440 	"If the -l option is omitted, the command will auto detect the layout based on the data in the EEPROM.\n"
441 	"The values which can be provided with the -l option are:\n"
442 	CONFIG_EEPROM_LAYOUT_HELP_STRING"\n"
443 #endif
444 )
445