1 // SPDX-License-Identifier: GPL-2.0+
3 * (C) Copyright 2000, 2001
4 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
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.
14 * Use the following configuration options to ensure no unneeded performance
15 * degradation (typical for EEPROM) is incured for FRAM memory:
17 * #define CONFIG_SYS_I2C_FRAM
18 * #undef CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS
26 #include <eeprom_layout.h>
28 #ifndef CONFIG_SYS_I2C_SPEED
29 #define CONFIG_SYS_I2C_SPEED 50000
32 #ifndef CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS
33 #define CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS 0
36 #ifndef CONFIG_SYS_EEPROM_PAGE_WRITE_BITS
37 #define CONFIG_SYS_EEPROM_PAGE_WRITE_BITS 8
41 #define I2C_RXTX_LEN 128
44 #define EEPROM_PAGE_SIZE (1 << CONFIG_SYS_EEPROM_PAGE_WRITE_BITS)
45 #define EEPROM_PAGE_OFFSET(x) ((x) & (EEPROM_PAGE_SIZE - 1))
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.
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.
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
62 __weak int eeprom_write_enable(unsigned dev_addr, int state)
67 void eeprom_init(int bus)
70 #if defined(CONFIG_SYS_I2C)
73 i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
77 static int eeprom_addr(unsigned dev_addr, unsigned offset, uchar *addr)
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 */
88 addr[0] = offset >> 16; /* block number */
89 addr[1] = offset >> 8; /* upper address octet */
90 addr[2] = blk_off; /* lower address octet */
92 #endif /* CONFIG_SYS_I2C_EEPROM_ADDR_LEN */
94 addr[0] |= dev_addr; /* insert device address */
99 static int eeprom_len(unsigned offset, unsigned end)
101 unsigned len = end - offset;
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
108 #if !defined(CONFIG_SYS_I2C_FRAM)
109 unsigned blk_off = offset & 0xff;
110 unsigned maxlen = EEPROM_PAGE_SIZE - EEPROM_PAGE_OFFSET(blk_off);
112 if (maxlen > I2C_RXTX_LEN)
113 maxlen = I2C_RXTX_LEN;
122 static int eeprom_rw_block(unsigned offset, uchar *addr, unsigned alen,
123 uchar *buffer, unsigned len, bool read)
127 #if defined(CONFIG_SYS_I2C_EEPROM_BUS)
128 i2c_set_bus_num(CONFIG_SYS_I2C_EEPROM_BUS);
132 ret = i2c_read(addr[0], offset, alen - 1, buffer, len);
134 ret = i2c_write(addr[0], offset, alen - 1, buffer, len);
142 static int eeprom_rw(unsigned dev_addr, unsigned offset, uchar *buffer,
143 unsigned cnt, bool read)
145 unsigned end = offset + cnt;
150 while (offset < end) {
151 alen = eeprom_addr(dev_addr, offset, addr);
153 len = eeprom_len(offset, end);
155 rcode = eeprom_rw_block(offset, addr, alen, buffer, len, read);
161 udelay(CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS * 1000);
167 int eeprom_read(unsigned dev_addr, unsigned offset, uchar *buffer, unsigned cnt)
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.
174 return eeprom_rw(dev_addr, offset, buffer, cnt, 1);
177 int eeprom_write(unsigned dev_addr, unsigned offset,
178 uchar *buffer, unsigned cnt)
182 eeprom_write_enable(dev_addr, 1);
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.
189 ret = eeprom_rw(dev_addr, offset, buffer, cnt, 0);
191 eeprom_write_enable(dev_addr, 0);
195 static int parse_numeric_param(char *str)
198 int value = simple_strtol(str, &endptr, 16);
200 return (*endptr != '\0') ? -1 : value;
204 * parse_i2c_bus_addr - parse the i2c bus and i2c devaddr parameters
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
212 * @returns: number of arguments parsed or CMD_RET_USAGE if error
214 static int parse_i2c_bus_addr(int *i2c_bus, ulong *i2c_addr, int argc,
215 char * const argv[], int argc_no_bus_addr)
217 int argc_no_bus = argc_no_bus_addr + 1;
218 int argc_bus_addr = argc_no_bus_addr + 2;
220 #ifdef CONFIG_SYS_DEF_EEPROM_ADDR
221 if (argc == argc_no_bus_addr) {
223 *i2c_addr = CONFIG_SYS_DEF_EEPROM_ADDR;
228 if (argc == argc_no_bus) {
230 *i2c_addr = parse_numeric_param(argv[0]);
235 if (argc == argc_bus_addr) {
236 *i2c_bus = parse_numeric_param(argv[0]);
237 *i2c_addr = parse_numeric_param(argv[1]);
242 return CMD_RET_USAGE;
245 #ifdef CONFIG_CMD_EEPROM_LAYOUT
247 __weak int eeprom_parse_layout_version(char *str)
249 return LAYOUT_VERSION_UNRECOGNIZED;
252 static unsigned char eeprom_buf[CONFIG_SYS_EEPROM_SIZE];
261 EEPROM_ACTION_INVALID,
264 static enum eeprom_action parse_action(char *cmd)
266 if (!strncmp(cmd, "read", 4))
268 if (!strncmp(cmd, "write", 5))
270 #ifdef CONFIG_CMD_EEPROM_LAYOUT
271 if (!strncmp(cmd, "print", 5))
273 if (!strncmp(cmd, "update", 6))
274 return EEPROM_UPDATE;
277 return EEPROM_ACTION_INVALID;
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)
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;
291 if (action == EEPROM_ACTION_INVALID)
292 return CMD_RET_USAGE;
294 eeprom_init(i2c_bus);
295 if (action == EEPROM_READ) {
296 printf(fmt, i2c_addr, "read", addr, off, cnt);
298 rcode = eeprom_read(i2c_addr, off, (uchar *)addr, cnt);
302 } else if (action == EEPROM_WRITE) {
303 printf(fmt, i2c_addr, "write", addr, off, cnt);
305 rcode = eeprom_write(i2c_addr, off, (uchar *)addr, cnt);
311 #ifdef CONFIG_CMD_EEPROM_LAYOUT
312 rcode = eeprom_read(i2c_addr, 0, eeprom_buf, CONFIG_SYS_EEPROM_SIZE);
316 eeprom_layout_setup(&layout, eeprom_buf, CONFIG_SYS_EEPROM_SIZE,
319 if (action == EEPROM_PRINT) {
320 layout.print(&layout);
324 layout.update(&layout, key, value);
326 rcode = eeprom_write(i2c_addr, 0, layout.data, CONFIG_SYS_EEPROM_SIZE);
332 #define NEXT_PARAM(argc, index) { (argc)--; (index)++; }
333 int do_eeprom(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
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;
340 char *field_name = "";
341 char *field_value = "";
344 return CMD_RET_USAGE;
346 NEXT_PARAM(argc, index); /* Skip program name */
348 action = parse_action(argv[index]);
349 NEXT_PARAM(argc, index);
351 if (action == EEPROM_ACTION_INVALID)
352 return CMD_RET_USAGE;
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);
367 ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
371 ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
375 ret = parse_i2c_bus_addr(&i2c_bus, &i2c_addr, argc,
379 /* Get compiler to stop whining */
380 return CMD_RET_USAGE;
383 if (ret == CMD_RET_USAGE)
387 NEXT_PARAM(argc, index);
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]);
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);
406 return eeprom_execute_command(action, i2c_bus, i2c_addr, layout_ver,
407 field_name, field_value, addr, off, cnt);
411 eeprom, 8, 1, do_eeprom,
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
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"
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"