Merge branch 'u-boot-samsung/master' into 'u-boot-arm/master'
[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[CONFIG_ENV_SIZE];
86         unsigned int off = CONFIG_ENV_OFFSET;
87
88 #ifdef CONFIG_ENV_OFFSET_REDUND
89         if (gd->env_valid == 2)
90                 off = CONFIG_ENV_OFFSET_REDUND;
91 #endif
92         eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
93                         off, (uchar *)buf, CONFIG_ENV_SIZE);
94
95         env_import(buf, 1);
96 }
97
98 int saveenv(void)
99 {
100         env_t   env_new;
101         int     rc;
102         unsigned int off        = CONFIG_ENV_OFFSET;
103 #ifdef CONFIG_ENV_OFFSET_REDUND
104         unsigned int off_red    = CONFIG_ENV_OFFSET_REDUND;
105         char flag_obsolete      = OBSOLETE_FLAG;
106 #endif
107
108         BUG_ON(env_ptr != NULL);
109
110         rc = env_export(&env_new);
111         if (rc)
112                 return rc;
113
114 #ifdef CONFIG_ENV_OFFSET_REDUND
115         if (gd->env_valid == 1) {
116                 off     = CONFIG_ENV_OFFSET_REDUND;
117                 off_red = CONFIG_ENV_OFFSET;
118         }
119
120         env_new.flags = ACTIVE_FLAG;
121 #endif
122
123         rc = eeprom_bus_write(CONFIG_SYS_DEF_EEPROM_ADDR,
124                               off, (uchar *)&env_new, CONFIG_ENV_SIZE);
125
126 #ifdef CONFIG_ENV_OFFSET_REDUND
127         if (rc == 0) {
128                 eeprom_bus_write(CONFIG_SYS_DEF_EEPROM_ADDR,
129                                  off_red + offsetof(env_t, flags),
130                                  (uchar *)&flag_obsolete, 1);
131
132                 if (gd->env_valid == 1)
133                         gd->env_valid = 2;
134                 else
135                         gd->env_valid = 1;
136         }
137 #endif
138         return rc;
139 }
140
141 /*
142  * Initialize Environment use
143  *
144  * We are still running from ROM, so data use is limited.
145  * Use a (moderately small) buffer on the stack
146  */
147 #ifdef CONFIG_ENV_OFFSET_REDUND
148 int env_init(void)
149 {
150         ulong len, crc[2], crc_tmp;
151         unsigned int off, off_env[2];
152         uchar buf[64], flags[2];
153         int i, crc_ok[2] = {0, 0};
154
155         eeprom_init();  /* prepare for EEPROM read/write */
156
157         off_env[0] = CONFIG_ENV_OFFSET;
158         off_env[1] = CONFIG_ENV_OFFSET_REDUND;
159
160         for (i = 0; i < 2; i++) {
161                 /* read CRC */
162                 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
163                                 off_env[i] + offsetof(env_t, crc),
164                                 (uchar *)&crc[i], sizeof(ulong));
165                 /* read FLAGS */
166                 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
167                                 off_env[i] + offsetof(env_t, flags),
168                                 (uchar *)&flags[i], sizeof(uchar));
169
170                 crc_tmp = 0;
171                 len = ENV_SIZE;
172                 off = off_env[i] + offsetof(env_t, data);
173                 while (len > 0) {
174                         int n = (len > sizeof(buf)) ? sizeof(buf) : len;
175
176                         eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR, off,
177                                         buf, n);
178
179                         crc_tmp = crc32(crc_tmp, buf, n);
180                         len -= n;
181                         off += n;
182                 }
183
184                 if (crc_tmp == crc[i])
185                         crc_ok[i] = 1;
186         }
187
188         if (!crc_ok[0] && !crc_ok[1]) {
189                 gd->env_addr    = 0;
190                 gd->env_valid   = 0;
191
192                 return 0;
193         } else if (crc_ok[0] && !crc_ok[1]) {
194                 gd->env_valid = 1;
195         } else if (!crc_ok[0] && crc_ok[1]) {
196                 gd->env_valid = 2;
197         } else {
198                 /* both ok - check serial */
199                 if (flags[0] == ACTIVE_FLAG && flags[1] == OBSOLETE_FLAG)
200                         gd->env_valid = 1;
201                 else if (flags[0] == OBSOLETE_FLAG && flags[1] == ACTIVE_FLAG)
202                         gd->env_valid = 2;
203                 else if (flags[0] == 0xFF && flags[1] == 0)
204                         gd->env_valid = 2;
205                 else if (flags[1] == 0xFF && flags[0] == 0)
206                         gd->env_valid = 1;
207                 else /* flags are equal - almost impossible */
208                         gd->env_valid = 1;
209         }
210
211         if (gd->env_valid == 2)
212                 gd->env_addr = off_env[1] + offsetof(env_t, data);
213         else if (gd->env_valid == 1)
214                 gd->env_addr = off_env[0] + offsetof(env_t, data);
215
216         return 0;
217 }
218 #else
219 int env_init(void)
220 {
221         ulong crc, len, new;
222         unsigned off;
223         uchar buf[64];
224
225         eeprom_init();  /* prepare for EEPROM read/write */
226
227         /* read old CRC */
228         eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
229                         CONFIG_ENV_OFFSET + offsetof(env_t, crc),
230                         (uchar *)&crc, sizeof(ulong));
231
232         new = 0;
233         len = ENV_SIZE;
234         off = offsetof(env_t, data);
235
236         while (len > 0) {
237                 int n = (len > sizeof(buf)) ? sizeof(buf) : len;
238
239                 eeprom_bus_read(CONFIG_SYS_DEF_EEPROM_ADDR,
240                                 CONFIG_ENV_OFFSET + off, buf, n);
241                 new = crc32(new, buf, n);
242                 len -= n;
243                 off += n;
244         }
245
246         if (crc == new) {
247                 gd->env_addr    = offsetof(env_t, data);
248                 gd->env_valid   = 1;
249         } else {
250                 gd->env_addr    = 0;
251                 gd->env_valid   = 0;
252         }
253
254         return 0;
255 }
256 #endif