2 * (C) Copyright 2000-2010
3 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
5 * (C) Copyright 2001 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
6 * Andreas Heppel <aheppel@sysgo.de>
8 * SPDX-License-Identifier: GPL-2.0+
13 #include <environment.h>
14 #include <linux/stddef.h>
15 #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
20 #include <linux/compiler.h> /* for BUG_ON */
22 DECLARE_GLOBAL_DATA_PTR
;
24 static int eeprom_bus_read(unsigned dev_addr
, unsigned offset
,
25 uchar
*buffer
, unsigned cnt
)
28 #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
29 int old_bus
= i2c_get_bus_num();
31 if (old_bus
!= CONFIG_I2C_ENV_EEPROM_BUS
)
32 i2c_set_bus_num(CONFIG_I2C_ENV_EEPROM_BUS
);
35 rcode
= eeprom_read(dev_addr
, offset
, buffer
, cnt
);
37 #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
38 i2c_set_bus_num(old_bus
);
44 static int eeprom_bus_write(unsigned dev_addr
, unsigned offset
,
45 uchar
*buffer
, unsigned cnt
)
48 #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
49 int old_bus
= i2c_get_bus_num();
51 if (old_bus
!= CONFIG_I2C_ENV_EEPROM_BUS
)
52 i2c_set_bus_num(CONFIG_I2C_ENV_EEPROM_BUS
);
55 rcode
= eeprom_write(dev_addr
, offset
, buffer
, cnt
);
57 #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
58 i2c_set_bus_num(old_bus
);
64 static int env_eeprom_get_char(int index
)
67 unsigned int off
= CONFIG_ENV_OFFSET
;
69 #ifdef CONFIG_ENV_OFFSET_REDUND
70 if (gd
->env_valid
== ENV_REDUND
)
71 off
= CONFIG_ENV_OFFSET_REDUND
;
73 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR
,
74 off
+ index
+ offsetof(env_t
, data
), &c
, 1);
79 static int env_eeprom_load(void)
81 char buf_env
[CONFIG_ENV_SIZE
];
82 unsigned int off
= CONFIG_ENV_OFFSET
;
84 #ifdef CONFIG_ENV_OFFSET_REDUND
85 ulong len
, crc
[2], crc_tmp
;
86 unsigned int off_env
[2];
87 uchar rdbuf
[64], flags
[2];
88 int i
, crc_ok
[2] = {0, 0};
90 eeprom_init(-1); /* prepare for EEPROM read/write */
92 off_env
[0] = CONFIG_ENV_OFFSET
;
93 off_env
[1] = CONFIG_ENV_OFFSET_REDUND
;
95 for (i
= 0; i
< 2; i
++) {
97 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR
,
98 off_env
[i
] + offsetof(env_t
, crc
),
99 (uchar
*)&crc
[i
], sizeof(ulong
));
101 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR
,
102 off_env
[i
] + offsetof(env_t
, flags
),
103 (uchar
*)&flags
[i
], sizeof(uchar
));
107 off
= off_env
[i
] + offsetof(env_t
, data
);
109 int n
= (len
> sizeof(rdbuf
)) ? sizeof(rdbuf
) : len
;
111 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR
, off
,
114 crc_tmp
= crc32(crc_tmp
, rdbuf
, n
);
119 if (crc_tmp
== crc
[i
])
123 if (!crc_ok
[0] && !crc_ok
[1]) {
125 gd
->env_valid
= ENV_INVALID
;
126 } else if (crc_ok
[0] && !crc_ok
[1]) {
127 gd
->env_valid
= ENV_VALID
;
128 } else if (!crc_ok
[0] && crc_ok
[1]) {
129 gd
->env_valid
= ENV_REDUND
;
131 /* both ok - check serial */
132 if (flags
[0] == ACTIVE_FLAG
&& flags
[1] == OBSOLETE_FLAG
)
133 gd
->env_valid
= ENV_VALID
;
134 else if (flags
[0] == OBSOLETE_FLAG
&& flags
[1] == ACTIVE_FLAG
)
135 gd
->env_valid
= ENV_REDUND
;
136 else if (flags
[0] == 0xFF && flags
[1] == 0)
137 gd
->env_valid
= ENV_REDUND
;
138 else if (flags
[1] == 0xFF && flags
[0] == 0)
139 gd
->env_valid
= ENV_VALID
;
140 else /* flags are equal - almost impossible */
141 gd
->env_valid
= ENV_VALID
;
144 #else /* CONFIG_ENV_OFFSET_REDUND */
148 eeprom_init(-1); /* prepare for EEPROM read/write */
151 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR
,
152 CONFIG_ENV_OFFSET
+ offsetof(env_t
, crc
),
153 (uchar
*)&crc
, sizeof(ulong
));
157 off
= offsetof(env_t
, data
);
159 int n
= (len
> sizeof(rdbuf
)) ? sizeof(rdbuf
) : len
;
161 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR
,
162 CONFIG_ENV_OFFSET
+ off
, rdbuf
, n
);
163 new = crc32(new, rdbuf
, n
);
169 gd
->env_valid
= ENV_VALID
;
171 gd
->env_valid
= ENV_INVALID
;
173 #endif /* CONFIG_ENV_OFFSET_REDUND */
175 off
= CONFIG_ENV_OFFSET
;
176 #ifdef CONFIG_ENV_OFFSET_REDUND
177 if (gd
->env_valid
== ENV_REDUND
)
178 off
= CONFIG_ENV_OFFSET_REDUND
;
181 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR
,
182 off
, (uchar
*)buf_env
, CONFIG_ENV_SIZE
);
184 env_import(buf_env
, 1);
189 static int env_eeprom_save(void)
193 unsigned int off
= CONFIG_ENV_OFFSET
;
194 #ifdef CONFIG_ENV_OFFSET_REDUND
195 unsigned int off_red
= CONFIG_ENV_OFFSET_REDUND
;
196 char flag_obsolete
= OBSOLETE_FLAG
;
199 rc
= env_export(&env_new
);
203 #ifdef CONFIG_ENV_OFFSET_REDUND
204 if (gd
->env_valid
== ENV_VALID
) {
205 off
= CONFIG_ENV_OFFSET_REDUND
;
206 off_red
= CONFIG_ENV_OFFSET
;
209 env_new
.flags
= ACTIVE_FLAG
;
212 rc
= eeprom_bus_write(CONFIG_SYS_DEF_EEPROM_ADDR
,
213 off
, (uchar
*)&env_new
, CONFIG_ENV_SIZE
);
215 #ifdef CONFIG_ENV_OFFSET_REDUND
217 eeprom_bus_write(CONFIG_SYS_DEF_EEPROM_ADDR
,
218 off_red
+ offsetof(env_t
, flags
),
219 (uchar
*)&flag_obsolete
, 1);
221 if (gd
->env_valid
== ENV_VALID
)
222 gd
->env_valid
= ENV_REDUND
;
224 gd
->env_valid
= ENV_VALID
;
230 U_BOOT_ENV_LOCATION(eeprom
) = {
231 .location
= ENVL_EEPROM
,
233 .get_char
= env_eeprom_get_char
,
234 .load
= env_eeprom_load
,
235 .save
= env_save_ptr(env_eeprom_save
),