1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
|
/*
* (C) Copyright 2000, 2001
* Wolfgang Denk, DENX Software Engineering, wd@denx.de.
*
* SPDX-License-Identifier: GPL-2.0+
*/
/*
* Support for read and write access to EEPROM like memory devices. This
* includes regular EEPROM as well as FRAM (ferroelectic nonvolaile RAM).
* FRAM devices read and write data at bus speed. In particular, there is no
* write delay. Also, there is no limit imposed on the number of bytes that can
* be transferred with a single read or write.
*
* Use the following configuration options to ensure no unneeded performance
* degradation (typical for EEPROM) is incured for FRAM memory:
*
* #define CONFIG_SYS_I2C_FRAM
* #undef CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS
*
*/
#include <common.h>
#include <config.h>
#include <command.h>
#include <i2c.h>
#ifndef CONFIG_SYS_I2C_SPEED
#define CONFIG_SYS_I2C_SPEED 50000
#endif
#ifndef CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS
#define CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS 0
#endif
#ifndef CONFIG_SYS_EEPROM_PAGE_WRITE_BITS
#define CONFIG_SYS_EEPROM_PAGE_WRITE_BITS 8
#endif
#define EEPROM_PAGE_SIZE (1 << CONFIG_SYS_EEPROM_PAGE_WRITE_BITS)
#define EEPROM_PAGE_OFFSET(x) ((x) & (EEPROM_PAGE_SIZE - 1))
/*
* for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 2 (16-bit EEPROM address) offset is
* 0x000nxxxx for EEPROM address selectors at n, offset xxxx in EEPROM.
*
* for CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1 (8-bit EEPROM page address) offset is
* 0x00000nxx for EEPROM address selectors and page number at n.
*/
#if !defined(CONFIG_SPI) || defined(CONFIG_ENV_EEPROM_IS_ON_I2C)
#if !defined(CONFIG_SYS_I2C_EEPROM_ADDR_LEN) || \
(CONFIG_SYS_I2C_EEPROM_ADDR_LEN < 1) || \
(CONFIG_SYS_I2C_EEPROM_ADDR_LEN > 2)
#error CONFIG_SYS_I2C_EEPROM_ADDR_LEN must be 1 or 2
#endif
#endif
__weak int eeprom_write_enable(unsigned dev_addr, int state)
{
return 0;
}
void eeprom_init(int bus)
{
/* SPI EEPROM */
#if defined(CONFIG_SPI) && !defined(CONFIG_ENV_EEPROM_IS_ON_I2C)
spi_init_f();
#endif
/* I2C EEPROM */
#if defined(CONFIG_HARD_I2C) || defined(CONFIG_SYS_I2C_SOFT)
#if defined(CONFIG_SYS_I2C)
if (bus >= 0)
i2c_set_bus_num(bus);
#endif
i2c_init(CONFIG_SYS_I2C_SPEED, CONFIG_SYS_I2C_SLAVE);
#endif
}
static int eeprom_addr(unsigned dev_addr, unsigned offset, uchar *addr)
{
unsigned blk_off;
int alen;
blk_off = offset & 0xff; /* block offset */
#if CONFIG_SYS_I2C_EEPROM_ADDR_LEN == 1
addr[0] = offset >> 8; /* block number */
addr[1] = blk_off; /* block offset */
alen = 2;
#else
addr[0] = offset >> 16; /* block number */
addr[1] = offset >> 8; /* upper address octet */
addr[2] = blk_off; /* lower address octet */
alen = 3;
#endif /* CONFIG_SYS_I2C_EEPROM_ADDR_LEN */
addr[0] |= dev_addr; /* insert device address */
return alen;
}
static int eeprom_len(unsigned offset, unsigned end)
{
unsigned len = end - offset;
/*
* For a FRAM device there is no limit on the number of the
* bytes that can be ccessed with the single read or write
* operation.
*/
#if !defined(CONFIG_SYS_I2C_FRAM)
unsigned blk_off = offset & 0xff;
unsigned maxlen = EEPROM_PAGE_SIZE - EEPROM_PAGE_OFFSET(blk_off);
if (maxlen > I2C_RXTX_LEN)
maxlen = I2C_RXTX_LEN;
if (len > maxlen)
len = maxlen;
#endif
return len;
}
static int eeprom_rw_block(unsigned offset, uchar *addr, unsigned alen,
uchar *buffer, unsigned len, bool read)
{
int ret = 0;
/* SPI */
#if defined(CONFIG_SPI) && !defined(CONFIG_ENV_EEPROM_IS_ON_I2C)
if (read)
spi_read(addr, alen, buffer, len);
else
spi_write(addr, alen, buffer, len);
#else /* I2C */
#if defined(CONFIG_SYS_I2C_EEPROM_BUS)
i2c_set_bus_num(CONFIG_SYS_I2C_EEPROM_BUS);
#endif
if (read)
ret = i2c_read(addr[0], offset, alen - 1, buffer, len);
else
ret = i2c_write(addr[0], offset, alen - 1, buffer, len);
if (ret)
ret = 1;
#endif
return ret;
}
static int eeprom_rw(unsigned dev_addr, unsigned offset, uchar *buffer,
unsigned cnt, bool read)
{
unsigned end = offset + cnt;
unsigned alen, len;
int rcode = 0;
uchar addr[3];
while (offset < end) {
alen = eeprom_addr(dev_addr, offset, addr);
len = eeprom_len(offset, end);
rcode = eeprom_rw_block(offset, addr, alen, buffer, len, read);
buffer += len;
offset += len;
if (!read)
udelay(CONFIG_SYS_EEPROM_PAGE_WRITE_DELAY_MS * 1000);
}
return rcode;
}
int eeprom_read(unsigned dev_addr, unsigned offset, uchar *buffer, unsigned cnt)
{
/*
* Read data until done or would cross a page boundary.
* We must write the address again when changing pages
* because the next page may be in a different device.
*/
return eeprom_rw(dev_addr, offset, buffer, cnt, 1);
}
int eeprom_write(unsigned dev_addr, unsigned offset,
uchar *buffer, unsigned cnt)
{
int ret;
eeprom_write_enable(dev_addr, 1);
/*
* Write data until done or would cross a write page boundary.
* We must write the address again when changing pages
* because the address counter only increments within a page.
*/
ret = eeprom_rw(dev_addr, offset, buffer, cnt, 0);
eeprom_write_enable(dev_addr, 0);
return ret;
}
static int do_eeprom(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
const char *const fmt =
"\nEEPROM @0x%lX %s: addr %08lx off %04lx count %ld ... ";
char * const *args = &argv[2];
int rcode;
ulong dev_addr, addr, off, cnt;
int bus_addr;
switch (argc) {
#ifdef CONFIG_SYS_DEF_EEPROM_ADDR
case 5:
bus_addr = -1;
dev_addr = CONFIG_SYS_DEF_EEPROM_ADDR;
break;
#endif
case 6:
bus_addr = -1;
dev_addr = simple_strtoul(*args++, NULL, 16);
break;
case 7:
bus_addr = simple_strtoul(*args++, NULL, 16);
dev_addr = simple_strtoul(*args++, NULL, 16);
break;
default:
return CMD_RET_USAGE;
}
addr = simple_strtoul(*args++, NULL, 16);
off = simple_strtoul(*args++, NULL, 16);
cnt = simple_strtoul(*args++, NULL, 16);
eeprom_init(bus_addr);
if (strcmp(argv[1], "read") == 0) {
printf(fmt, dev_addr, argv[1], addr, off, cnt);
rcode = eeprom_read(dev_addr, off, (uchar *)addr, cnt);
puts("done\n");
return rcode;
} else if (strcmp(argv[1], "write") == 0) {
printf(fmt, dev_addr, argv[1], addr, off, cnt);
rcode = eeprom_write(dev_addr, off, (uchar *)addr, cnt);
puts("done\n");
return rcode;
}
return CMD_RET_USAGE;
}
U_BOOT_CMD(
eeprom, 7, 1, do_eeprom,
"EEPROM sub-system",
"read <bus> <devaddr> addr off cnt\n"
"eeprom write <bus> <devaddr> addr off cnt\n"
" - read/write `cnt' bytes from `devaddr` EEPROM at offset `off'"
)
|
