xref: /openbmc/u-boot/cmd/eeprom.c (revision 35f9d9bd)
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_SYS_I2C_EEPROM_BUS)
128 	i2c_set_bus_num(CONFIG_SYS_I2C_EEPROM_BUS);
129 #endif
130 
131 	if (read)
132 		ret = i2c_read(addr[0], offset, alen - 1, buffer, len);
133 	else
134 		ret = i2c_write(addr[0], offset, alen - 1, buffer, len);
135 
136 	if (ret)
137 		ret = 1;
138 
139 	return ret;
140 }
141 
142 static int eeprom_rw(unsigned dev_addr, unsigned offset, uchar *buffer,
143 		     unsigned cnt, bool read)
144 {
145 	unsigned end = offset + cnt;
146 	unsigned alen, len;
147 	int rcode = 0;
148 	uchar addr[3];
149 
150 	while (offset < end) {
151 		alen = eeprom_addr(dev_addr, offset, addr);
152 
153 		len = eeprom_len(offset, end);
154 
155 		rcode = eeprom_rw_block(offset, addr, alen, buffer, len, read);
156 
157 		buffer += len;
158 		offset += len;
159 
160 		if (!read)
161 			udelay(CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS * 1000);
162 	}
163 
164 	return rcode;
165 }
166 
167 int eeprom_read(unsigned dev_addr, unsigned offset, uchar *buffer, unsigned cnt)
168 {
169 	/*
170 	 * Read data until done or would cross a page boundary.
171 	 * We must write the address again when changing pages
172 	 * because the next page may be in a different device.
173 	 */
174 	return eeprom_rw(dev_addr, offset, buffer, cnt, 1);
175 }
176 
177 int eeprom_write(unsigned dev_addr, unsigned offset,
178 		 uchar *buffer, unsigned cnt)
179 {
180 	int ret;
181 
182 	eeprom_write_enable(dev_addr, 1);
183 
184 	/*
185 	 * Write data until done or would cross a write page boundary.
186 	 * We must write the address again when changing pages
187 	 * because the address counter only increments within a page.
188 	 */
189 	ret = eeprom_rw(dev_addr, offset, buffer, cnt, 0);
190 
191 	eeprom_write_enable(dev_addr, 0);
192 	return ret;
193 }
194 
195 static int parse_numeric_param(char *str)
196 {
197 	char *endptr;
198 	int value = simple_strtol(str, &endptr, 16);
199 
200 	return (*endptr != '\0') ? -1 : value;
201 }
202 
203 /**
204  * parse_i2c_bus_addr - parse the i2c bus and i2c devaddr parameters
205  *
206  * @i2c_bus:	address to store the i2c bus
207  * @i2c_addr:	address to store the device i2c address
208  * @argc:	count of command line arguments left to parse
209  * @argv:	command line arguments left to parse
210  * @argc_no_bus_addr:	argc value we expect to see when bus & addr aren't given
211  *
212  * @returns:	number of arguments parsed or CMD_RET_USAGE if error
213  */
214 static int parse_i2c_bus_addr(int *i2c_bus, ulong *i2c_addr, int argc,
215 			      char * const argv[], int argc_no_bus_addr)
216 {
217 	int argc_no_bus = argc_no_bus_addr + 1;
218 	int argc_bus_addr = argc_no_bus_addr + 2;
219 
220 #ifdef CONFIG_SYS_DEF_EEPROM_ADDR
221 	if (argc == argc_no_bus_addr) {
222 		*i2c_bus = -1;
223 		*i2c_addr = CONFIG_SYS_DEF_EEPROM_ADDR;
224 
225 		return 0;
226 	}
227 #endif
228 	if (argc == argc_no_bus) {
229 		*i2c_bus = -1;
230 		*i2c_addr = parse_numeric_param(argv[0]);
231 
232 		return 1;
233 	}
234 
235 	if (argc == argc_bus_addr) {
236 		*i2c_bus = parse_numeric_param(argv[0]);
237 		*i2c_addr = parse_numeric_param(argv[1]);
238 
239 		return 2;
240 	}
241 
242 	return CMD_RET_USAGE;
243 }
244 
245 #ifdef CONFIG_CMD_EEPROM_LAYOUT
246 
247 __weak int eeprom_parse_layout_version(char *str)
248 {
249 	return LAYOUT_VERSION_UNRECOGNIZED;
250 }
251 
252 static unsigned char eeprom_buf[CONFIG_SYS_EEPROM_SIZE];
253 
254 #endif
255 
256 enum eeprom_action {
257 	EEPROM_READ,
258 	EEPROM_WRITE,
259 	EEPROM_PRINT,
260 	EEPROM_UPDATE,
261 	EEPROM_ACTION_INVALID,
262 };
263 
264 static enum eeprom_action parse_action(char *cmd)
265 {
266 	if (!strncmp(cmd, "read", 4))
267 		return EEPROM_READ;
268 	if (!strncmp(cmd, "write", 5))
269 		return EEPROM_WRITE;
270 #ifdef CONFIG_CMD_EEPROM_LAYOUT
271 	if (!strncmp(cmd, "print", 5))
272 		return EEPROM_PRINT;
273 	if (!strncmp(cmd, "update", 6))
274 		return EEPROM_UPDATE;
275 #endif
276 
277 	return EEPROM_ACTION_INVALID;
278 }
279 
280 static int eeprom_execute_command(enum eeprom_action action, int i2c_bus,
281 				  ulong i2c_addr, int layout_ver, char *key,
282 				  char *value, ulong addr, ulong off, ulong cnt)
283 {
284 	int rcode = 0;
285 	const char *const fmt =
286 		"\nEEPROM @0x%lX %s: addr %08lx  off %04lx  count %ld ... ";
287 #ifdef CONFIG_CMD_EEPROM_LAYOUT
288 	struct eeprom_layout layout;
289 #endif
290 
291 	if (action == EEPROM_ACTION_INVALID)
292 		return CMD_RET_USAGE;
293 
294 	eeprom_init(i2c_bus);
295 	if (action == EEPROM_READ) {
296 		printf(fmt, i2c_addr, "read", addr, off, cnt);
297 
298 		rcode = eeprom_read(i2c_addr, off, (uchar *)addr, cnt);
299 
300 		puts("done\n");
301 		return rcode;
302 	} else if (action == EEPROM_WRITE) {
303 		printf(fmt, i2c_addr, "write", addr, off, cnt);
304 
305 		rcode = eeprom_write(i2c_addr, off, (uchar *)addr, cnt);
306 
307 		puts("done\n");
308 		return rcode;
309 	}
310 
311 #ifdef CONFIG_CMD_EEPROM_LAYOUT
312 	rcode = eeprom_read(i2c_addr, 0, eeprom_buf, CONFIG_SYS_EEPROM_SIZE);
313 	if (rcode < 0)
314 		return rcode;
315 
316 	eeprom_layout_setup(&layout, eeprom_buf, CONFIG_SYS_EEPROM_SIZE,
317 			    layout_ver);
318 
319 	if (action == EEPROM_PRINT) {
320 		layout.print(&layout);
321 		return 0;
322 	}
323 
324 	layout.update(&layout, key, value);
325 
326 	rcode = eeprom_write(i2c_addr, 0, layout.data, CONFIG_SYS_EEPROM_SIZE);
327 #endif
328 
329 	return rcode;
330 }
331 
332 #define NEXT_PARAM(argc, index)	{ (argc)--; (index)++; }
333 int do_eeprom(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
334 {
335 	int layout_ver = LAYOUT_VERSION_AUTODETECT;
336 	enum eeprom_action action = EEPROM_ACTION_INVALID;
337 	int i2c_bus = -1, index = 0;
338 	ulong i2c_addr = -1, addr = 0, cnt = 0, off = 0;
339 	int ret;
340 	char *field_name = "";
341 	char *field_value = "";
342 
343 	if (argc <= 1)
344 		return CMD_RET_USAGE;
345 
346 	NEXT_PARAM(argc, index); /* Skip program name */
347 
348 	action = parse_action(argv[index]);
349 	NEXT_PARAM(argc, index);
350 
351 	if (action == EEPROM_ACTION_INVALID)
352 		return CMD_RET_USAGE;
353 
354 #ifdef CONFIG_CMD_EEPROM_LAYOUT
355 	if (action == EEPROM_PRINT || action == EEPROM_UPDATE) {
356 		if (!strcmp(argv[index], "-l")) {
357 			NEXT_PARAM(argc, index);
358 			layout_ver = eeprom_parse_layout_version(argv[index]);
359 			NEXT_PARAM(argc, index);
360 		}
361 	}
362 #endif
363 
364 	switch (action) {
365 	case EEPROM_READ:
366 	case EEPROM_WRITE:
367 		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
368 					 argv + index, 3);
369 		break;
370 	case EEPROM_PRINT:
371 		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
372 					 argv + index, 0);
373 		break;
374 	case EEPROM_UPDATE:
375 		ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
376 					 argv + index, 2);
377 		break;
378 	default:
379 		/* Get compiler to stop whining */
380 		return CMD_RET_USAGE;
381 	}
382 
383 	if (ret == CMD_RET_USAGE)
384 		return ret;
385 
386 	while (ret--)
387 		NEXT_PARAM(argc, index);
388 
389 	if (action == EEPROM_READ || action == EEPROM_WRITE) {
390 		addr = parse_numeric_param(argv[index]);
391 		NEXT_PARAM(argc, index);
392 		off = parse_numeric_param(argv[index]);
393 		NEXT_PARAM(argc, index);
394 		cnt = parse_numeric_param(argv[index]);
395 	}
396 
397 #ifdef CONFIG_CMD_EEPROM_LAYOUT
398 	if (action == EEPROM_UPDATE) {
399 		field_name = argv[index];
400 		NEXT_PARAM(argc, index);
401 		field_value = argv[index];
402 		NEXT_PARAM(argc, index);
403 	}
404 #endif
405 
406 	return eeprom_execute_command(action, i2c_bus, i2c_addr, layout_ver,
407 				      field_name, field_value, addr, off, cnt);
408 }
409 
410 U_BOOT_CMD(
411 	eeprom,	8,	1,	do_eeprom,
412 	"EEPROM sub-system",
413 	"read  <bus> <devaddr> addr off cnt\n"
414 	"eeprom write <bus> <devaddr> addr off cnt\n"
415 	"       - read/write `cnt' bytes from `devaddr` EEPROM at offset `off'"
416 #ifdef CONFIG_CMD_EEPROM_LAYOUT
417 	"\n"
418 	"eeprom print [-l <layout_version>] <bus> <devaddr>\n"
419 	"       - Print layout fields and their data in human readable format\n"
420 	"eeprom update [-l <layout_version>] <bus> <devaddr> field_name field_value\n"
421 	"       - Update a specific eeprom field with new data.\n"
422 	"         The new data must be written in the same human readable format as shown by the print command.\n"
423 	"\n"
424 	"LAYOUT VERSIONS\n"
425 	"The -l option can be used to force the command to interpret the EEPROM data using the chosen layout.\n"
426 	"If the -l option is omitted, the command will auto detect the layout based on the data in the EEPROM.\n"
427 	"The values which can be provided with the -l option are:\n"
428 	CONFIG_EEPROM_LAYOUT_HELP_STRING"\n"
429 #endif
430 )
431