LXR uboot/common/env

   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
  22DECLARE_GLOBAL_DATA_PTR;
  23
  24env_t *env_ptr;
  25
  26char *env_name_spec = "EEPROM";
  27
  28static 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
  48static 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
  68uchar 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
  83void 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
 191int 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 */
 240int env_init(void)
 241{
 242        gd->env_addr = (ulong)&default_environment[0];
 243        gd->env_valid = 1;
 244        return 0;
 245}
 246