xref: /openbmc/u-boot/cmd/eeprom.c (revision 8ee59472)
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_SYS_I2C_EEPROM_BUS)
141 	i2c_set_bus_num(CONFIG_SYS_I2C_EEPROM_BUS);
142 #endif
143 
144 	if (read)
145 		ret = i2c_read(addr[0], offset, alen - 1, buffer, len);
146 	else
147 		ret = i2c_write(addr[0], offset, alen - 1, buffer, len);
148 
149 	if (ret)
150 		ret = 1;
151 #endif
152 	return ret;
153 }
154 
155 static int eeprom_rw(unsigned dev_addr, unsigned offset, uchar *buffer,
156 		     unsigned cnt, bool read)
157 {
158 	unsigned end = offset + cnt;
159 	unsigned alen, len;
160 	int rcode = 0;
161 	uchar addr[3];
162 
163 	while (offset < end) {
164 		alen = eeprom_addr(dev_addr, offset, addr);
165 
166 		len = eeprom_len(offset, end);
167 
168 		rcode = eeprom_rw_block(offset, addr, alen, buffer, len, read);
169 
170 		buffer += len;
171 		offset += len;
172 
173 		if (!read)
174 			udelay(CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS * 1000);
175 	}
176 
177 	return rcode;
178 }
179 
180 int eeprom_read(unsigned dev_addr, unsigned offset, uchar *buffer, unsigned cnt)
181 {
182 	/*
183 	 * Read data until done or would cross a page boundary.
184 	 * We must write the address again when changing pages
185 	 * because the next page may be in a different device.
186 	 */
187 	return eeprom_rw(dev_addr, offset, buffer, cnt, 1);
188 }
189 
190 int eeprom_write(unsigned dev_addr, unsigned offset,
191 		 uchar *buffer, unsigned cnt)
192 {
193 	int ret;
194 
195 	eeprom_write_enable(dev_addr, 1);
196 
197 	/*
198 	 * Write data until done or would cross a write page boundary.
199 	 * We must write the address again when changing pages
200 	 * because the address counter only increments within a page.
201 	 */
202 	ret = eeprom_rw(dev_addr, offset, buffer, cnt, 0);
203 
204 	eeprom_write_enable(dev_addr, 0);
205 	return ret;
206 }
207 
208 static int parse_numeric_param(char *str)
209 {
210 	char *endptr;
211 	int value = simple_strtol(str, &endptr, 16);
212 
213 	return (*endptr != '\0') ? -1 : value;
214 }
215 
216 /**
217  * parse_i2c_bus_addr - parse the i2c bus and i2c devaddr parameters
218  *
219  * @i2c_bus:	address to store the i2c bus
220  * @i2c_addr:	address to store the device i2c address
221  * @argc:	count of command line arguments left to parse
222  * @argv:	command line arguments left to parse
223  * @argc_no_bus_addr:	argc value we expect to see when bus & addr aren't given
224  *
225  * @returns:	number of arguments parsed or CMD_RET_USAGE if error
226  */
227 static int parse_i2c_bus_addr(int *i2c_bus, ulong *i2c_addr, int argc,
228 			      char * const argv[], int argc_no_bus_addr)
229 {
230 	int argc_no_bus = argc_no_bus_addr + 1;
231 	int argc_bus_addr = argc_no_bus_addr + 2;
232 
233 #ifdef CONFIG_SYS_DEF_EEPROM_ADDR
234 	if (argc == argc_no_bus_addr) {
235 		*i2c_bus = -1;
236 		*i2c_addr = CONFIG_SYS_DEF_EEPROM_ADDR;
237 
238 		return 0;
239 	}
240 #endif
241 	if (argc == argc_no_bus) {
242 		*i2c_bus = -1;
243 		*i2c_addr = parse_numeric_param(argv[0]);
244 
245 		return 1;
246 	}
247 
248 	if (argc == argc_bus_addr) {
249 		*i2c_bus = parse_numeric_param(argv[0]);
250 		*i2c_addr = parse_numeric_param(argv[1]);
251 
252 		return 2;
253 	}
254 
255 	return CMD_RET_USAGE;
256 }
257 
258 #ifdef CONFIG_CMD_EEPROM_LAYOUT
259 
260 __weak int eeprom_parse_layout_version(char *str)
261 {
262 	return LAYOUT_VERSION_UNRECOGNIZED;
263 }
264 
265 static unsigned char eeprom_buf[CONFIG_SYS_EEPROM_SIZE];
266 
267 #endif
268 
269 enum eeprom_action {
270 	EEPROM_READ,
271 	EEPROM_WRITE,
272 	EEPROM_PRINT,
273 	EEPROM_UPDATE,
274 	EEPROM_ACTION_INVALID,
275 };
276 
277 static enum eeprom_action parse_action(char *cmd)
278 {
279 	if (!strncmp(cmd, "read", 4))
280 		return EEPROM_READ;
281 	if (!strncmp(cmd, "write", 5))
282 		return EEPROM_WRITE;
283 #ifdef CONFIG_CMD_EEPROM_LAYOUT
284 	if (!strncmp(cmd, "print", 5))
285 		return EEPROM_PRINT;
286 	if (!strncmp(cmd, "update", 6))
287 		return EEPROM_UPDATE;
288 #endif
289 
290 	return EEPROM_ACTION_INVALID;
291 }
292 
293 static int eeprom_execute_command(enum eeprom_action action, int i2c_bus,
294 				  ulong i2c_addr, int layout_ver, char *key,
295 				  char *value, ulong addr, ulong off, ulong cnt)
296 {
297 	int rcode = 0;
298 	const char *const fmt =
299 		"\nEEPROM @0x%lX %s: addr %08lx  off %04lx  count %ld ... ";
300 #ifdef CONFIG_CMD_EEPROM_LAYOUT
301 	struct eeprom_layout layout;
302 #endif
303 
304 	if (action == EEPROM_ACTION_INVALID)
305 		return CMD_RET_USAGE;
306 
307 	eeprom_init(i2c_bus);
308 	if (action == EEPROM_READ) {
309 		printf(fmt, i2c_addr, "read", addr, off, cnt);
310 
311 		rcode = eeprom_read(i2c_addr, off, (uchar *)addr, cnt);
312 
313 		puts("done\n");
314 		return rcode;
315 	} else if (action == EEPROM_WRITE) {
316 		printf(fmt, i2c_addr, "write", addr, off, cnt);
317 
318 		rcode = eeprom_write(i2c_addr, off, (uchar *)addr, cnt);
319 
320 		puts("done\n");
321 		return rcode;
322 	}
323 
324 #ifdef CONFIG_CMD_EEPROM_LAYOUT
325 	rcode = eeprom_read(i2c_addr, 0, eeprom_buf, CONFIG_SYS_EEPROM_SIZE);
326 	if (rcode < 0)
327 		return rcode;
328 
329 	eeprom_layout_setup(&layout, eeprom_buf, CONFIG_SYS_EEPROM_SIZE,
330 			    layout_ver);
331 
332 	if (action == EEPROM_PRINT) {
333 		layout.print(&layout);
334 		return 0;
335 	}
336 
337 	layout.update(&layout, key, value);
338 
339 	rcode = eeprom_write(i2c_addr, 0, layout.data, CONFIG_SYS_EEPROM_SIZE);
340 #endif
341 
342 	return rcode;
343 }
344 
345 #define NEXT_PARAM(argc, index)	{ (argc)--; (index)++; }
346 int do_eeprom(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
347 {
348 	int layout_ver = LAYOUT_VERSION_AUTODETECT;
349 	enum eeprom_action action = EEPROM_ACTION_INVALID;
350 	int i2c_bus = -1, index = 0;
351 	ulong i2c_addr = -1, addr = 0, cnt = 0, off = 0;
352 	int ret;
353 	char *field_name = "";
354 	char *field_value = "";
355 
356 	if (argc <= 1)
357 		return CMD_RET_USAGE;
358 
359 	NEXT_PARAM(argc, index); /* Skip program name */
360 
361 	action = parse_action(argv[index]);
362 	NEXT_PARAM(argc, index);
363 
364 	if (action == EEPROM_ACTION_INVALID)
365 		return CMD_RET_USAGE;
366 
367 #ifdef CONFIG_CMD_EEPROM_LAYOUT
368 	if (action == EEPROM_PRINT || action == EEPROM_UPDATE) {
369 		if (!strcmp(argv[index], "-l")) {
370 			NEXT_PARAM(argc, index);
371 			layout_ver = eeprom_parse_layout_version(argv[index]);
372 			NEXT_PARAM(argc, index);
373 		}
374 	}
375 #endif
376 
377 	switch (action) {
378 	case EEPROM_READ:
379 	case EEPROM_WRITE:
380 		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
381 					 argv + index, 3);
382 		break;
383 	case EEPROM_PRINT:
384 		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
385 					 argv + index, 0);
386 		break;
387 	case EEPROM_UPDATE:
388 		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
389 					 argv + index, 2);
390 		break;
391 	default:
392 		/* Get compiler to stop whining */
393 		return CMD_RET_USAGE;
394 	}
395 
396 	if (ret == CMD_RET_USAGE)
397 		return ret;
398 
399 	while (ret--)
400 		NEXT_PARAM(argc, index);
401 
402 	if (action == EEPROM_READ || action == EEPROM_WRITE) {
403 		addr = parse_numeric_param(argv[index]);
404 		NEXT_PARAM(argc, index);
405 		off = parse_numeric_param(argv[index]);
406 		NEXT_PARAM(argc, index);
407 		cnt = parse_numeric_param(argv[index]);
408 	}
409 
410 #ifdef CONFIG_CMD_EEPROM_LAYOUT
411 	if (action == EEPROM_UPDATE) {
412 		field_name = argv[index];
413 		NEXT_PARAM(argc, index);
414 		field_value = argv[index];
415 		NEXT_PARAM(argc, index);
416 	}
417 #endif
418 
419 	return eeprom_execute_command(action, i2c_bus, i2c_addr, layout_ver,
420 				      field_name, field_value, addr, off, cnt);
421 }
422 
423 U_BOOT_CMD(
424 	eeprom,	8,	1,	do_eeprom,
425 	"EEPROM sub-system",
426 	"read  <bus> <devaddr> addr off cnt\n"
427 	"eeprom write <bus> <devaddr> addr off cnt\n"
428 	"       - read/write `cnt' bytes from `devaddr` EEPROM at offset `off'"
429 #ifdef CONFIG_CMD_EEPROM_LAYOUT
430 	"\n"
431 	"eeprom print [-l <layout_version>] <bus> <devaddr>\n"
432 	"       - Print layout fields and their data in human readable format\n"
433 	"eeprom update [-l <layout_version>] <bus> <devaddr> field_name field_value\n"
434 	"       - Update a specific eeprom field with new data.\n"
435 	"         The new data must be written in the same human readable format as shown by the print command.\n"
436 	"\n"
437 	"LAYOUT VERSIONS\n"
438 	"The -l option can be used to force the command to interpret the EEPROM data using the chosen layout.\n"
439 	"If the -l option is omitted, the command will auto detect the layout based on the data in the EEPROM.\n"
440 	"The values which can be provided with the -l option are:\n"
441 	CONFIG_EEPROM_LAYOUT_HELP_STRING"\n"
442 #endif
443 )
444