2 * (C) Copyright 2000, 2001
3 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 * See file CREDITS for list of people who contributed to this
8 * This program is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License as
10 * published by the Free Software Foundation; either version 2 of
11 * the License, or (at your option) any later version.
13 * This program is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with this program; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
26 * Support for read and write access to EEPROM like memory devices. This
27 * includes regular EEPROM as well as FRAM (ferroelectic nonvolaile RAM).
28 * FRAM devices read and write data at bus speed. In particular, there is no
29 * write delay. Also, there is no limit imposed on the numer of bytes that can
30 * be transferred with a single read or write.
32 * Use the following configuration options to ensure no unneeded performance
33 * degradation (typical for EEPROM) is incured for FRAM memory:
35 * #define CFG_I2C_FRAM
36 * #undef CFG_EEPROM_PAGE_WRITE_DELAY_MS
45 #if (CONFIG_COMMANDS & CFG_CMD_EEPROM) || defined(CFG_ENV_IS_IN_EEPROM)
47 extern void eeprom_init (void);
48 extern int eeprom_read (unsigned dev_addr
, unsigned offset
,
49 uchar
*buffer
, unsigned cnt
);
50 extern int eeprom_write (unsigned dev_addr
, unsigned offset
,
51 uchar
*buffer
, unsigned cnt
);
52 #if defined(CFG_EEPROM_WREN)
53 extern int eeprom_write_enable (unsigned dev_addr
, int state
);
58 #if defined(CFG_EEPROM_X40430)
59 /* Maximum number of times to poll for acknowledge after write */
60 #define MAX_ACKNOWLEDGE_POLLS 10
63 /* ------------------------------------------------------------------------- */
65 #if (CONFIG_COMMANDS & CFG_CMD_EEPROM)
66 int do_eeprom ( cmd_tbl_t
* cmdtp
, int flag
, int argc
, char *argv
[])
68 const char *const fmt
=
69 "\nEEPROM @0x%lX %s: addr %08lx off %04lx count %ld ... ";
71 #if defined(CFG_I2C_MULTI_EEPROMS)
73 ulong dev_addr
= simple_strtoul (argv
[2], NULL
, 16);
74 ulong addr
= simple_strtoul (argv
[3], NULL
, 16);
75 ulong off
= simple_strtoul (argv
[4], NULL
, 16);
76 ulong cnt
= simple_strtoul (argv
[5], NULL
, 16);
79 ulong dev_addr
= CFG_DEF_EEPROM_ADDR
;
80 ulong addr
= simple_strtoul (argv
[2], NULL
, 16);
81 ulong off
= simple_strtoul (argv
[3], NULL
, 16);
82 ulong cnt
= simple_strtoul (argv
[4], NULL
, 16);
83 #endif /* CFG_I2C_MULTI_EEPROMS */
87 # endif /* !CONFIG_SPI */
89 if (strcmp (argv
[1], "read") == 0) {
92 printf (fmt
, dev_addr
, argv
[1], addr
, off
, cnt
);
94 rcode
= eeprom_read (dev_addr
, off
, (uchar
*) addr
, cnt
);
98 } else if (strcmp (argv
[1], "write") == 0) {
101 printf (fmt
, dev_addr
, argv
[1], addr
, off
, cnt
);
103 rcode
= eeprom_write (dev_addr
, off
, (uchar
*) addr
, cnt
);
110 printf ("Usage:\n%s\n", cmdtp
->usage
);
113 #endif /* CFG_CMD_EEPROM */
115 /*-----------------------------------------------------------------------
117 * for CFG_I2C_EEPROM_ADDR_LEN == 2 (16-bit EEPROM address) offset is
118 * 0x000nxxxx for EEPROM address selectors at n, offset xxxx in EEPROM.
120 * for CFG_I2C_EEPROM_ADDR_LEN == 1 (8-bit EEPROM page address) offset is
121 * 0x00000nxx for EEPROM address selectors and page number at n.
124 #if (CONFIG_COMMANDS & CFG_CMD_EEPROM) || defined(CFG_ENV_IS_IN_EEPROM)
127 #if !defined(CFG_I2C_EEPROM_ADDR_LEN) || CFG_I2C_EEPROM_ADDR_LEN < 1 || CFG_I2C_EEPROM_ADDR_LEN > 2
128 #error CFG_I2C_EEPROM_ADDR_LEN must be 1 or 2
132 int eeprom_read (unsigned dev_addr
, unsigned offset
, uchar
*buffer
, unsigned cnt
)
134 unsigned end
= offset
+ cnt
;
138 /* Read data until done or would cross a page boundary.
139 * We must write the address again when changing pages
140 * because the next page may be in a different device.
142 while (offset
< end
) {
144 #if !defined(CFG_I2C_FRAM)
148 #if CFG_I2C_EEPROM_ADDR_LEN == 1 && !defined(CONFIG_SPI_X)
151 blk_off
= offset
& 0xFF; /* block offset */
153 addr
[0] = offset
>> 8; /* block number */
154 addr
[1] = blk_off
; /* block offset */
159 blk_off
= offset
& 0xFF; /* block offset */
161 addr
[0] = offset
>> 16; /* block number */
162 addr
[1] = offset
>> 8; /* upper address octet */
163 addr
[2] = blk_off
; /* lower address octet */
165 #endif /* CFG_I2C_EEPROM_ADDR_LEN, CONFIG_SPI_X */
167 addr
[0] |= dev_addr
; /* insert device address */
172 * For a FRAM device there is no limit on the number of the
173 * bytes that can be ccessed with the single read or write
176 #if !defined(CFG_I2C_FRAM)
177 maxlen
= 0x100 - blk_off
;
178 if (maxlen
> I2C_RXTX_LEN
)
179 maxlen
= I2C_RXTX_LEN
;
185 spi_read (addr
, alen
, buffer
, len
);
187 if (i2c_read (addr
[0], offset
, alen
-1, buffer
, len
) != 0)
197 /*-----------------------------------------------------------------------
199 * for CFG_I2C_EEPROM_ADDR_LEN == 2 (16-bit EEPROM address) offset is
200 * 0x000nxxxx for EEPROM address selectors at n, offset xxxx in EEPROM.
202 * for CFG_I2C_EEPROM_ADDR_LEN == 1 (8-bit EEPROM page address) offset is
203 * 0x00000nxx for EEPROM address selectors and page number at n.
206 int eeprom_write (unsigned dev_addr
, unsigned offset
, uchar
*buffer
, unsigned cnt
)
208 unsigned end
= offset
+ cnt
;
212 #if defined(CFG_EEPROM_X40430)
213 uchar contr_r_addr
[2];
220 #if defined(CFG_EEPROM_WREN)
221 eeprom_write_enable (dev_addr
,1);
223 /* Write data until done or would cross a write page boundary.
224 * We must write the address again when changing pages
225 * because the address counter only increments within a page.
228 while (offset
< end
) {
230 #if !defined(CFG_I2C_FRAM)
234 #if CFG_I2C_EEPROM_ADDR_LEN == 1 && !defined(CONFIG_SPI_X)
237 blk_off
= offset
& 0xFF; /* block offset */
239 addr
[0] = offset
>> 8; /* block number */
240 addr
[1] = blk_off
; /* block offset */
245 blk_off
= offset
& 0xFF; /* block offset */
247 addr
[0] = offset
>> 16; /* block number */
248 addr
[1] = offset
>> 8; /* upper address octet */
249 addr
[2] = blk_off
; /* lower address octet */
251 #endif /* CFG_I2C_EEPROM_ADDR_LEN, CONFIG_SPI_X */
253 addr
[0] |= dev_addr
; /* insert device address */
258 * For a FRAM device there is no limit on the number of the
259 * bytes that can be ccessed with the single read or write
262 #if !defined(CFG_I2C_FRAM)
264 #if defined(CFG_EEPROM_PAGE_WRITE_BITS)
266 #define EEPROM_PAGE_SIZE (1 << CFG_EEPROM_PAGE_WRITE_BITS)
267 #define EEPROM_PAGE_OFFSET(x) ((x) & (EEPROM_PAGE_SIZE - 1))
269 maxlen
= EEPROM_PAGE_SIZE
- EEPROM_PAGE_OFFSET(blk_off
);
271 maxlen
= 0x100 - blk_off
;
273 if (maxlen
> I2C_RXTX_LEN
)
274 maxlen
= I2C_RXTX_LEN
;
281 spi_write (addr
, alen
, buffer
, len
);
283 #if defined(CFG_EEPROM_X40430)
284 /* Get the value of the control register.
285 * Set current address (internal pointer in the x40430)
289 contr_r_addr
[1] = 0xff;
291 addr_void
[1] = addr
[1];
292 #ifdef CFG_I2C_EEPROM_ADDR
293 contr_r_addr
[0] |= CFG_I2C_EEPROM_ADDR
;
294 addr_void
[0] |= CFG_I2C_EEPROM_ADDR
;
297 if (i2c_read (contr_r_addr
[0], contr_r_addr
[1], 1, contr_reg
, 1) != 0) {
300 ctrl_reg_v
= contr_reg
[0];
302 /* Are any of the eeprom blocks write protected?
304 if (ctrl_reg_v
& 0x18) {
305 ctrl_reg_v
&= ~0x18; /* reset block protect bits */
306 ctrl_reg_v
|= 0x02; /* set write enable latch */
307 ctrl_reg_v
&= ~0x04; /* clear RWEL */
309 /* Set write enable latch.
312 if (i2c_write (contr_r_addr
[0], 0xff, 1, contr_reg
, 1) != 0) {
316 /* Set register write enable latch.
319 if (i2c_write (contr_r_addr
[0], 0xFF, 1, contr_reg
, 1) != 0) {
323 /* Modify ctrl register.
325 contr_reg
[0] = ctrl_reg_v
;
326 if (i2c_write (contr_r_addr
[0], 0xFF, 1, contr_reg
, 1) != 0) {
330 /* The write (above) is an operation on NV memory.
331 * These can take some time (~5ms), and the device
332 * will not respond to further I2C messages till
333 * it's completed the write.
334 * So poll device for an I2C acknowledge.
335 * When we get one we know we can continue with other
339 for (i
= 0; i
< MAX_ACKNOWLEDGE_POLLS
; i
++) {
340 if (i2c_read (addr_void
[0], addr_void
[1], 1, contr_reg
, 1) == 0)
342 #if defined(CFG_EEPROM_PAGE_WRITE_DELAY_MS)
343 udelay(CFG_EEPROM_PAGE_WRITE_DELAY_MS
* 1000);
346 if (i
== MAX_ACKNOWLEDGE_POLLS
) {
347 puts ("EEPROM poll acknowledge failed\n");
352 /* Is the write enable latch on?.
354 else if (!(ctrl_reg_v
& 0x02)) {
355 /* Set write enable latch.
358 if (i2c_write (contr_r_addr
[0], 0xFF, 1, contr_reg
, 1) != 0) {
362 /* Write is enabled ... now write eeprom value.
365 if (i2c_write (addr
[0], offset
, alen
-1, buffer
, len
) != 0)
372 #if defined(CFG_EEPROM_PAGE_WRITE_DELAY_MS)
373 udelay(CFG_EEPROM_PAGE_WRITE_DELAY_MS
* 1000);
376 #if defined(CFG_EEPROM_WREN)
377 eeprom_write_enable (dev_addr
,0);
384 eeprom_probe (unsigned dev_addr
, unsigned offset
)
388 /* Probe the chip address
390 #if CFG_I2C_EEPROM_ADDR_LEN == 1 && !defined(CONFIG_SPI_X)
391 chip
= offset
>> 8; /* block number */
393 chip
= offset
>> 16; /* block number */
394 #endif /* CFG_I2C_EEPROM_ADDR_LEN, CONFIG_SPI_X */
396 chip
|= dev_addr
; /* insert device address */
398 return (i2c_probe (chip
));
402 /*-----------------------------------------------------------------------
405 #ifndef CFG_I2C_SPEED
406 #define CFG_I2C_SPEED 50000
409 #ifndef CFG_I2C_SLAVE
410 #define CFG_I2C_SLAVE 0xFE
413 void eeprom_init (void)
415 #if defined(CONFIG_SPI)
418 #if defined(CONFIG_HARD_I2C) || \
419 defined(CONFIG_SOFT_I2C)
420 i2c_init (CFG_I2C_SPEED
, CFG_I2C_SLAVE
);
423 /*-----------------------------------------------------------------------
425 #endif /* CFG_CMD_EEPROM */
426 /***************************************************/
428 #if (CONFIG_COMMANDS & CFG_CMD_EEPROM)
430 #ifdef CFG_I2C_MULTI_EEPROMS
432 eeprom
, 6, 1, do_eeprom
,
433 "eeprom - EEPROM sub-system\n",
434 "read devaddr addr off cnt\n"
435 "eeprom write devaddr addr off cnt\n"
436 " - read/write `cnt' bytes from `devaddr` EEPROM at offset `off'\n"
438 #else /* One EEPROM */
440 eeprom
, 5, 1, do_eeprom
,
441 "eeprom - EEPROM sub-system\n",
442 "read addr off cnt\n"
443 "eeprom write addr off cnt\n"
444 " - read/write `cnt' bytes at EEPROM offset `off'\n"
446 #endif /* CFG_I2C_MULTI_EEPROMS */
448 #endif /* CFG_CMD_EEPROM */