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 * Set CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS to 0
27 #include <eeprom_layout.h>
28 #include <linux/delay.h>
31 #define I2C_RXTX_LEN 128
34 #define EEPROM_PAGE_SIZE (1 << CONFIG_SYS_EEPROM_PAGE_WRITE_BITS)
35 #define EEPROM_PAGE_OFFSET(x) ((x) & (EEPROM_PAGE_SIZE - 1))
37 #if CONFIG_IS_ENABLED(DM_I2C)
38 static int eeprom_i2c_bus
;
41 __weak
int eeprom_write_enable(unsigned dev_addr
, int state
)
46 void eeprom_init(int bus
)
49 #if CONFIG_IS_ENABLED(DM_I2C)
51 #elif CONFIG_IS_ENABLED(SYS_I2C_LEGACY)
54 i2c_init(CONFIG_SYS_I2C_SPEED
, CONFIG_SYS_I2C_SLAVE
);
59 * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 2 (16-bit EEPROM address) offset is
60 * 0x000nxxxx for EEPROM address selectors at n, offset xxxx in EEPROM.
62 * for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1 (8-bit EEPROM page address) offset is
63 * 0x00000nxx for EEPROM address selectors and page number at n.
65 static int eeprom_addr(unsigned dev_addr
, unsigned offset
, uchar
*addr
)
70 blk_off
= offset
& 0xff; /* block offset */
71 #if CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1
72 addr
[0] = offset
>> 8; /* block number */
73 addr
[1] = blk_off
; /* block offset */
76 addr
[0] = offset
>> 16; /* block number */
77 addr
[1] = offset
>> 8; /* upper address octet */
78 addr
[2] = blk_off
; /* lower address octet */
80 #endif /* CONFIG_SYS_I2C_EEPROM_ADDR_LEN */
82 addr
[0] |= dev_addr
; /* insert device address */
87 static int eeprom_len(unsigned offset
, unsigned end
)
89 unsigned len
= end
- offset
;
92 * For a FRAM device there is no limit on the number of the
93 * bytes that can be accessed with the single read or write
96 #if !defined(CONFIG_SYS_I2C_FRAM)
97 unsigned blk_off
= offset
& 0xff;
98 unsigned maxlen
= EEPROM_PAGE_SIZE
- EEPROM_PAGE_OFFSET(blk_off
);
100 if (maxlen
> I2C_RXTX_LEN
)
101 maxlen
= I2C_RXTX_LEN
;
110 static int eeprom_rw_block(unsigned offset
, uchar
*addr
, unsigned alen
,
111 uchar
*buffer
, unsigned len
, bool read
)
115 #if CONFIG_IS_ENABLED(DM_I2C)
118 ret
= i2c_get_chip_for_busnum(eeprom_i2c_bus
, addr
[0],
121 printf("%s: Cannot find udev for a bus %d\n", __func__
,
123 return CMD_RET_FAILURE
;
127 ret
= dm_i2c_read(dev
, offset
, buffer
, len
);
129 ret
= dm_i2c_write(dev
, offset
, buffer
, len
);
131 #else /* Non DM I2C support - will be removed */
134 ret
= i2c_read(addr
[0], offset
, alen
- 1, buffer
, len
);
136 ret
= i2c_write(addr
[0], offset
, alen
- 1, buffer
, len
);
137 #endif /* CONFIG_DM_I2C */
139 ret
= CMD_RET_FAILURE
;
144 static int eeprom_rw(unsigned dev_addr
, unsigned offset
, uchar
*buffer
,
145 unsigned cnt
, bool read
)
147 unsigned end
= offset
+ cnt
;
152 #if !CONFIG_IS_ENABLED(DM_I2C) && defined(CONFIG_SYS_I2C_EEPROM_BUS)
153 eeprom_init(CONFIG_SYS_I2C_EEPROM_BUS
);
156 while (offset
< end
) {
157 alen
= eeprom_addr(dev_addr
, offset
, addr
);
159 len
= eeprom_len(offset
, end
);
161 rcode
= eeprom_rw_block(offset
, addr
, alen
, buffer
, len
, read
);
166 #if CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS > 0
168 udelay(CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS
* 1000);
175 int eeprom_read(unsigned dev_addr
, unsigned offset
, uchar
*buffer
, unsigned cnt
)
178 * Read data until done or would cross a page boundary.
179 * We must write the address again when changing pages
180 * because the next page may be in a different device.
182 return eeprom_rw(dev_addr
, offset
, buffer
, cnt
, 1);
185 int eeprom_write(unsigned dev_addr
, unsigned offset
,
186 uchar
*buffer
, unsigned cnt
)
190 eeprom_write_enable(dev_addr
, 1);
193 * Write data until done or would cross a write page boundary.
194 * We must write the address again when changing pages
195 * because the address counter only increments within a page.
197 ret
= eeprom_rw(dev_addr
, offset
, buffer
, cnt
, 0);
199 eeprom_write_enable(dev_addr
, 0);
203 static long parse_numeric_param(char *str
)
206 long value
= simple_strtol(str
, &endptr
, 16);
208 return (*endptr
!= '\0') ? -1 : value
;
212 * parse_i2c_bus_addr - parse the i2c bus and i2c devaddr parameters
214 * @i2c_bus: address to store the i2c bus
215 * @i2c_addr: address to store the device i2c address
216 * @argc: count of command line arguments left to parse
217 * @argv: command line arguments left to parse
218 * @argc_no_bus_addr: argc value we expect to see when bus & addr aren't given
220 * @returns: number of arguments parsed or CMD_RET_USAGE if error
222 static int parse_i2c_bus_addr(int *i2c_bus
, ulong
*i2c_addr
, int argc
,
223 char *const argv
[], int argc_no_bus_addr
)
225 int argc_no_bus
= argc_no_bus_addr
+ 1;
226 int argc_bus_addr
= argc_no_bus_addr
+ 2;
228 #ifdef CONFIG_SYS_I2C_EEPROM_ADDR
229 if (argc
== argc_no_bus_addr
) {
231 *i2c_addr
= CONFIG_SYS_I2C_EEPROM_ADDR
;
236 if (argc
== argc_no_bus
) {
238 *i2c_addr
= parse_numeric_param(argv
[0]);
243 if (argc
== argc_bus_addr
) {
244 *i2c_bus
= parse_numeric_param(argv
[0]);
245 *i2c_addr
= parse_numeric_param(argv
[1]);
250 return CMD_RET_USAGE
;
253 #ifdef CONFIG_CMD_EEPROM_LAYOUT
255 __weak
int eeprom_parse_layout_version(char *str
)
257 return LAYOUT_VERSION_UNRECOGNIZED
;
260 static unsigned char eeprom_buf
[CONFIG_SYS_EEPROM_SIZE
];
269 EEPROM_ACTION_INVALID
,
272 static enum eeprom_action
parse_action(char *cmd
)
274 if (!strncmp(cmd
, "read", 4))
276 if (!strncmp(cmd
, "write", 5))
278 #ifdef CONFIG_CMD_EEPROM_LAYOUT
279 if (!strncmp(cmd
, "print", 5))
281 if (!strncmp(cmd
, "update", 6))
282 return EEPROM_UPDATE
;
285 return EEPROM_ACTION_INVALID
;
288 static int eeprom_execute_command(enum eeprom_action action
, int i2c_bus
,
289 ulong i2c_addr
, int layout_ver
, char *key
,
290 char *value
, ulong addr
, ulong off
, ulong cnt
)
293 const char *const fmt
=
294 "\nEEPROM @0x%lX %s: addr 0x%08lx off 0x%04lx count %ld ... ";
295 #ifdef CONFIG_CMD_EEPROM_LAYOUT
296 struct eeprom_layout layout
;
299 if (action
== EEPROM_ACTION_INVALID
)
300 return CMD_RET_USAGE
;
302 eeprom_init(i2c_bus
);
303 if (action
== EEPROM_READ
) {
304 printf(fmt
, i2c_addr
, "read", addr
, off
, cnt
);
306 rcode
= eeprom_read(i2c_addr
, off
, (uchar
*)addr
, cnt
);
310 } else if (action
== EEPROM_WRITE
) {
311 printf(fmt
, i2c_addr
, "write", addr
, off
, cnt
);
313 rcode
= eeprom_write(i2c_addr
, off
, (uchar
*)addr
, cnt
);
319 #ifdef CONFIG_CMD_EEPROM_LAYOUT
320 rcode
= eeprom_read(i2c_addr
, 0, eeprom_buf
, CONFIG_SYS_EEPROM_SIZE
);
324 eeprom_layout_setup(&layout
, eeprom_buf
, CONFIG_SYS_EEPROM_SIZE
,
327 if (action
== EEPROM_PRINT
) {
328 layout
.print(&layout
);
332 layout
.update(&layout
, key
, value
);
334 rcode
= eeprom_write(i2c_addr
, 0, layout
.data
, CONFIG_SYS_EEPROM_SIZE
);
340 #define NEXT_PARAM(argc, index) { (argc)--; (index)++; }
341 int do_eeprom(struct cmd_tbl
*cmdtp
, int flag
, int argc
, char *const argv
[])
343 int layout_ver
= LAYOUT_VERSION_AUTODETECT
;
344 enum eeprom_action action
= EEPROM_ACTION_INVALID
;
345 int i2c_bus
= -1, index
= 0;
346 ulong i2c_addr
= -1, addr
= 0, cnt
= 0, off
= 0;
348 char *field_name
= "";
349 char *field_value
= "";
352 return CMD_RET_USAGE
;
354 NEXT_PARAM(argc
, index
); /* Skip program name */
356 action
= parse_action(argv
[index
]);
357 NEXT_PARAM(argc
, index
);
359 if (action
== EEPROM_ACTION_INVALID
)
360 return CMD_RET_USAGE
;
362 #ifdef CONFIG_CMD_EEPROM_LAYOUT
363 if (action
== EEPROM_PRINT
|| action
== EEPROM_UPDATE
) {
364 if (!strcmp(argv
[index
], "-l")) {
365 NEXT_PARAM(argc
, index
);
366 layout_ver
= eeprom_parse_layout_version(argv
[index
]);
367 NEXT_PARAM(argc
, index
);
375 ret
= parse_i2c_bus_addr(&i2c_bus
, &i2c_addr
, argc
,
379 ret
= parse_i2c_bus_addr(&i2c_bus
, &i2c_addr
, argc
,
383 ret
= parse_i2c_bus_addr(&i2c_bus
, &i2c_addr
, argc
,
387 /* Get compiler to stop whining */
388 return CMD_RET_USAGE
;
391 if (ret
== CMD_RET_USAGE
)
395 NEXT_PARAM(argc
, index
);
397 if (action
== EEPROM_READ
|| action
== EEPROM_WRITE
) {
398 addr
= parse_numeric_param(argv
[index
]);
399 NEXT_PARAM(argc
, index
);
400 off
= parse_numeric_param(argv
[index
]);
401 NEXT_PARAM(argc
, index
);
402 cnt
= parse_numeric_param(argv
[index
]);
405 #ifdef CONFIG_CMD_EEPROM_LAYOUT
406 if (action
== EEPROM_UPDATE
) {
407 field_name
= argv
[index
];
408 NEXT_PARAM(argc
, index
);
409 field_value
= argv
[index
];
410 NEXT_PARAM(argc
, index
);
414 return eeprom_execute_command(action
, i2c_bus
, i2c_addr
, layout_ver
,
415 field_name
, field_value
, addr
, off
, cnt
);
419 eeprom
, 8, 1, do_eeprom
,
421 "read <bus> <devaddr> addr off cnt\n"
422 "eeprom write <bus> <devaddr> addr off cnt\n"
423 " - read/write `cnt' bytes from `devaddr` EEPROM at offset `off'"
424 #ifdef CONFIG_CMD_EEPROM_LAYOUT
426 "eeprom print [-l <layout_version>] <bus> <devaddr>\n"
427 " - Print layout fields and their data in human readable format\n"
428 "eeprom update [-l <layout_version>] <bus> <devaddr> field_name field_value\n"
429 " - Update a specific eeprom field with new data.\n"
430 " The new data must be written in the same human readable format as shown by the print command.\n"
433 "The -l option can be used to force the command to interpret the EEPROM data using the chosen layout.\n"
434 "If the -l option is omitted, the command will auto detect the layout based on the data in the EEPROM.\n"
435 "The values which can be provided with the -l option are:\n"
436 CONFIG_EEPROM_LAYOUT_HELP_STRING
"\n"