1 // SPDX-License-Identifier: GPL-2.0+
3 * (C) Copyright 2000-2010
4 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
6 * (C) Copyright 2001 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
7 * Andreas Heppel <aheppel@sysgo.de>
13 #include <env_internal.h>
14 #include <linux/stddef.h>
15 #include <u-boot/crc.h>
16 #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
21 #include <linux/compiler.h> /* for BUG_ON */
23 DECLARE_GLOBAL_DATA_PTR;
25 static int eeprom_bus_read(unsigned dev_addr, unsigned offset,
26 uchar *buffer, unsigned cnt)
29 #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
30 int old_bus = i2c_get_bus_num();
32 if (old_bus != CONFIG_I2C_ENV_EEPROM_BUS)
33 i2c_set_bus_num(CONFIG_I2C_ENV_EEPROM_BUS);
36 rcode = eeprom_read(dev_addr, offset, buffer, cnt);
38 #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
39 i2c_set_bus_num(old_bus);
45 static int eeprom_bus_write(unsigned dev_addr, unsigned offset,
46 uchar *buffer, unsigned cnt)
49 #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
50 int old_bus = i2c_get_bus_num();
52 if (old_bus != CONFIG_I2C_ENV_EEPROM_BUS)
53 i2c_set_bus_num(CONFIG_I2C_ENV_EEPROM_BUS);
56 rcode = eeprom_write(dev_addr, offset, buffer, cnt);
58 #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
59 i2c_set_bus_num(old_bus);
65 /** Call this function from overridden env_get_char_spec() if you need
68 int env_eeprom_get_char(int index)
71 unsigned int off = CONFIG_ENV_OFFSET;
73 #ifdef CONFIG_ENV_OFFSET_REDUND
74 if (gd->env_valid == ENV_REDUND)
75 off = CONFIG_ENV_OFFSET_REDUND;
77 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
78 off + index + offsetof(env_t, data), &c, 1);
83 static int env_eeprom_load(void)
85 char buf_env[CONFIG_ENV_SIZE];
86 unsigned int off = CONFIG_ENV_OFFSET;
88 #ifdef CONFIG_ENV_OFFSET_REDUND
89 ulong len, crc[2], crc_tmp;
90 unsigned int off_env[2];
91 uchar rdbuf[64], flags[2];
92 int i, crc_ok[2] = {0, 0};
94 eeprom_init(-1); /* prepare for EEPROM read/write */
96 off_env[0] = CONFIG_ENV_OFFSET;
97 off_env[1] = CONFIG_ENV_OFFSET_REDUND;
99 for (i = 0; i < 2; i++) {
101 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
102 off_env[i] + offsetof(env_t, crc),
103 (uchar *)&crc[i], sizeof(ulong));
105 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
106 off_env[i] + offsetof(env_t, flags),
107 (uchar *)&flags[i], sizeof(uchar));
111 off = off_env[i] + offsetof(env_t, data);
113 int n = (len > sizeof(rdbuf)) ? sizeof(rdbuf) : len;
115 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR, off,
118 crc_tmp = crc32(crc_tmp, rdbuf, n);
123 if (crc_tmp == crc[i])
127 if (!crc_ok[0] && !crc_ok[1]) {
129 gd->env_valid = ENV_INVALID;
130 } else if (crc_ok[0] && !crc_ok[1]) {
131 gd->env_valid = ENV_VALID;
132 } else if (!crc_ok[0] && crc_ok[1]) {
133 gd->env_valid = ENV_REDUND;
135 /* both ok - check serial */
136 if (flags[0] == ENV_REDUND_ACTIVE &&
137 flags[1] == ENV_REDUND_OBSOLETE)
138 gd->env_valid = ENV_VALID;
139 else if (flags[0] == ENV_REDUND_OBSOLETE &&
140 flags[1] == ENV_REDUND_ACTIVE)
141 gd->env_valid = ENV_REDUND;
142 else if (flags[0] == 0xFF && flags[1] == 0)
143 gd->env_valid = ENV_REDUND;
144 else if (flags[1] == 0xFF && flags[0] == 0)
145 gd->env_valid = ENV_VALID;
146 else /* flags are equal - almost impossible */
147 gd->env_valid = ENV_VALID;
150 #else /* CONFIG_ENV_OFFSET_REDUND */
154 eeprom_init(-1); /* prepare for EEPROM read/write */
157 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
158 CONFIG_ENV_OFFSET + offsetof(env_t, crc),
159 (uchar *)&crc, sizeof(ulong));
163 off = offsetof(env_t, data);
165 int n = (len > sizeof(rdbuf)) ? sizeof(rdbuf) : len;
167 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
168 CONFIG_ENV_OFFSET + off, rdbuf, n);
169 new = crc32(new, rdbuf, n);
175 gd->env_valid = ENV_VALID;
177 gd->env_valid = ENV_INVALID;
179 #endif /* CONFIG_ENV_OFFSET_REDUND */
181 off = CONFIG_ENV_OFFSET;
182 #ifdef CONFIG_ENV_OFFSET_REDUND
183 if (gd->env_valid == ENV_REDUND)
184 off = CONFIG_ENV_OFFSET_REDUND;
187 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
188 off, (uchar *)buf_env, CONFIG_ENV_SIZE);
190 return env_import(buf_env, 1);
193 static int env_eeprom_save(void)
197 unsigned int off = CONFIG_ENV_OFFSET;
198 #ifdef CONFIG_ENV_OFFSET_REDUND
199 unsigned int off_red = CONFIG_ENV_OFFSET_REDUND;
200 char flag_obsolete = ENV_REDUND_OBSOLETE;
203 rc = env_export(&env_new);
207 #ifdef CONFIG_ENV_OFFSET_REDUND
208 if (gd->env_valid == ENV_VALID) {
209 off = CONFIG_ENV_OFFSET_REDUND;
210 off_red = CONFIG_ENV_OFFSET;
213 env_new.flags = ENV_REDUND_ACTIVE;
216 rc = eeprom_bus_write(CONFIG_SYS_DEF_EEPROM_ADDR,
217 off, (uchar *)&env_new, CONFIG_ENV_SIZE);
219 #ifdef CONFIG_ENV_OFFSET_REDUND
221 eeprom_bus_write(CONFIG_SYS_DEF_EEPROM_ADDR,
222 off_red + offsetof(env_t, flags),
223 (uchar *)&flag_obsolete, 1);
225 if (gd->env_valid == ENV_VALID)
226 gd->env_valid = ENV_REDUND;
228 gd->env_valid = ENV_VALID;
234 U_BOOT_ENV_LOCATION(eeprom) = {
235 .location = ENVL_EEPROM,
237 .load = env_eeprom_load,
238 .save = env_save_ptr(env_eeprom_save),