Merge branch 'master' of git://git.denx.de/u-boot-sunxi
[platform/kernel/u-boot.git] / common / env_eeprom.c
1 /*
2  * (C) Copyright 2000-2010
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * (C) Copyright 2001 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
6  * Andreas Heppel <aheppel@sysgo.de>
7  *
8  * SPDX-License-Identifier:     GPL-2.0+
9  */
10
11 #include <common.h>
12 #include <command.h>
13 #include <environment.h>
14 #include <linux/stddef.h>
15 #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
16 #include <i2c.h>
17 #endif
18 #include <search.h>
19 #include <errno.h>
20 #include <linux/compiler.h>     /* for BUG_ON */
21
22 DECLARE_GLOBAL_DATA_PTR;
23
24 env_t *env_ptr;
25
26 char *env_name_spec = "EEPROM";
27
28 static int eeprom_bus_read(unsigned dev_addr, unsigned offset,
29                            uchar *buffer, unsigned cnt)
30 {
31         int rcode;
32 #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
33         int old_bus = i2c_get_bus_num();
34
35         if (old_bus != CONFIG_I2C_ENV_EEPROM_BUS)
36                 i2c_set_bus_num(CONFIG_I2C_ENV_EEPROM_BUS);
37 #endif
38
39         rcode = eeprom_read(dev_addr, offset, buffer, cnt);
40
41 #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
42         i2c_set_bus_num(old_bus);
43 #endif
44
45         return rcode;
46 }
47
48 static int eeprom_bus_write(unsigned dev_addr, unsigned offset,
49                             uchar *buffer, unsigned cnt)
50 {
51         int rcode;
52 #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
53         int old_bus = i2c_get_bus_num();
54
55         if (old_bus != CONFIG_I2C_ENV_EEPROM_BUS)
56                 i2c_set_bus_num(CONFIG_I2C_ENV_EEPROM_BUS);
57 #endif
58
59         rcode = eeprom_write(dev_addr, offset, buffer, cnt);
60
61 #if defined(CONFIG_I2C_ENV_EEPROM_BUS)
62         i2c_set_bus_num(old_bus);
63 #endif
64
65         return rcode;
66 }
67
68 uchar env_get_char_spec(int index)
69 {
70         uchar c;
71         unsigned int off = CONFIG_ENV_OFFSET;
72
73 #ifdef CONFIG_ENV_OFFSET_REDUND
74         if (gd->env_valid == 2)
75                 off = CONFIG_ENV_OFFSET_REDUND;
76 #endif
77         eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
78                         off + index + offsetof(env_t, data), &c, 1);
79
80         return c;
81 }
82
83 void env_relocate_spec(void)
84 {
85         char buf_env[CONFIG_ENV_SIZE];
86         unsigned int off = CONFIG_ENV_OFFSET;
87
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};
93
94         eeprom_init(-1);        /* prepare for EEPROM read/write */
95
96         off_env[0] = CONFIG_ENV_OFFSET;
97         off_env[1] = CONFIG_ENV_OFFSET_REDUND;
98
99         for (i = 0; i < 2; i++) {
100                 /* read CRC */
101                 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
102                                 off_env[i] + offsetof(env_t, crc),
103                                 (uchar *)&crc[i], sizeof(ulong));
104                 /* read FLAGS */
105                 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
106                                 off_env[i] + offsetof(env_t, flags),
107                                 (uchar *)&flags[i], sizeof(uchar));
108
109                 crc_tmp = 0;
110                 len = ENV_SIZE;
111                 off = off_env[i] + offsetof(env_t, data);
112                 while (len > 0) {
113                         int n = (len > sizeof(rdbuf)) ? sizeof(rdbuf) : len;
114
115                         eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR, off,
116                                         rdbuf, n);
117
118                         crc_tmp = crc32(crc_tmp, rdbuf, n);
119                         len -= n;
120                         off += n;
121                 }
122
123                 if (crc_tmp == crc[i])
124                         crc_ok[i] = 1;
125         }
126
127         if (!crc_ok[0] && !crc_ok[1]) {
128                 gd->env_addr    = 0;
129                 gd->env_valid   = 0;
130         } else if (crc_ok[0] && !crc_ok[1]) {
131                 gd->env_valid = 1;
132         } else if (!crc_ok[0] && crc_ok[1]) {
133                 gd->env_valid = 2;
134         } else {
135                 /* both ok - check serial */
136                 if (flags[0] == ACTIVE_FLAG && flags[1] == OBSOLETE_FLAG)
137                         gd->env_valid = 1;
138                 else if (flags[0] == OBSOLETE_FLAG && flags[1] == ACTIVE_FLAG)
139                         gd->env_valid = 2;
140                 else if (flags[0] == 0xFF && flags[1] == 0)
141                         gd->env_valid = 2;
142                 else if (flags[1] == 0xFF && flags[0] == 0)
143                         gd->env_valid = 1;
144                 else /* flags are equal - almost impossible */
145                         gd->env_valid = 1;
146         }
147
148 #else /* CONFIG_ENV_OFFSET_REDUND */
149         ulong crc, len, new;
150         uchar rdbuf[64];
151
152         eeprom_init(-1);        /* prepare for EEPROM read/write */
153
154         /* read old CRC */
155         eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
156                         CONFIG_ENV_OFFSET + offsetof(env_t, crc),
157                         (uchar *)&crc, sizeof(ulong));
158
159         new = 0;
160         len = ENV_SIZE;
161         off = offsetof(env_t, data);
162         while (len > 0) {
163                 int n = (len > sizeof(rdbuf)) ? sizeof(rdbuf) : len;
164
165                 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
166                                 CONFIG_ENV_OFFSET + off, rdbuf, n);
167                 new = crc32(new, rdbuf, n);
168                 len -= n;
169                 off += n;
170         }
171
172         if (crc == new) {
173                 gd->env_valid   = 1;
174         } else {
175                 gd->env_valid   = 0;
176         }
177 #endif /* CONFIG_ENV_OFFSET_REDUND */
178
179         off = CONFIG_ENV_OFFSET;
180 #ifdef CONFIG_ENV_OFFSET_REDUND
181         if (gd->env_valid == 2)
182                 off = CONFIG_ENV_OFFSET_REDUND;
183 #endif
184
185         eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
186                 off, (uchar *)buf_env, CONFIG_ENV_SIZE);
187
188         env_import(buf_env, 1);
189 }
190
191 int saveenv(void)
192 {
193         env_t   env_new;
194         int     rc;
195         unsigned int off        = CONFIG_ENV_OFFSET;
196 #ifdef CONFIG_ENV_OFFSET_REDUND
197         unsigned int off_red    = CONFIG_ENV_OFFSET_REDUND;
198         char flag_obsolete      = OBSOLETE_FLAG;
199 #endif
200
201         BUG_ON(env_ptr != NULL);
202
203         rc = env_export(&env_new);
204         if (rc)
205                 return rc;
206
207 #ifdef CONFIG_ENV_OFFSET_REDUND
208         if (gd->env_valid == 1) {
209                 off     = CONFIG_ENV_OFFSET_REDUND;
210                 off_red = CONFIG_ENV_OFFSET;
211         }
212
213         env_new.flags = ACTIVE_FLAG;
214 #endif
215
216         rc = eeprom_bus_write(CONFIG_SYS_DEF_EEPROM_ADDR,
217                               off, (uchar *)&env_new, CONFIG_ENV_SIZE);
218
219 #ifdef CONFIG_ENV_OFFSET_REDUND
220         if (rc == 0) {
221                 eeprom_bus_write(CONFIG_SYS_DEF_EEPROM_ADDR,
222                                  off_red + offsetof(env_t, flags),
223                                  (uchar *)&flag_obsolete, 1);
224
225                 if (gd->env_valid == 1)
226                         gd->env_valid = 2;
227                 else
228                         gd->env_valid = 1;
229         }
230 #endif
231         return rc;
232 }
233
234 /*
235  * Initialize Environment use
236  *
237  * We are still running from ROM, so data use is limited.
238  * Use a (moderately small) buffer on the stack
239  */
240 int env_init(void)
241 {
242         gd->env_addr = (ulong)&default_environment[0];
243         gd->env_valid = 1;
244         return 0;
245 }