include/environment.h

   1 /*
   2  * (C) Copyright 2002
   3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21  * MA 02111-1307 USA
  22  */
  23
  24 #ifndef _ENVIRONMENT_H_
  25 #define _ENVIRONMENT_H_
  26
  27 /**************************************************************************
  28  *
  29  * The "environment" is stored as a list of '\0' terminated
  30  * "name=value" strings. The end of the list is marked by a double
  31  * '\0'. New entries are always added at the end. Deleting an entry
  32  * shifts the remaining entries to the front. Replacing an entry is a
  33  * combination of deleting the old value and adding the new one.
  34  *
  35  * The environment is preceeded by a 32 bit CRC over the data part.
  36  *
  37  **************************************************************************
  38  */
  39
  40 #if defined(CONFIG_ENV_IS_IN_FLASH)
  41 # ifndef        CONFIG_ENV_ADDR
  42 #  define       CONFIG_ENV_ADDR (CONFIG_SYS_FLASH_BASE + CONFIG_ENV_OFFSET)
  43 # endif
  44 # ifndef        CONFIG_ENV_OFFSET
  45 #  define       CONFIG_ENV_OFFSET (CONFIG_ENV_ADDR - CONFIG_SYS_FLASH_BASE)
  46 # endif
  47 # if !defined(CONFIG_ENV_ADDR_REDUND) && defined(CONFIG_ENV_OFFSET_REDUND)
  48 #  define       CONFIG_ENV_ADDR_REDUND  \
  49                 (CONFIG_SYS_FLASH_BASE + CONFIG_ENV_OFFSET_REDUND)
  50 # endif
  51 # if defined(CONFIG_ENV_SECT_SIZE) || defined(CONFIG_ENV_SIZE)
  52 #  ifndef       CONFIG_ENV_SECT_SIZE
  53 #   define      CONFIG_ENV_SECT_SIZE    CONFIG_ENV_SIZE
  54 #  endif
  55 #  ifndef       CONFIG_ENV_SIZE
  56 #   define      CONFIG_ENV_SIZE CONFIG_ENV_SECT_SIZE
  57 #  endif
  58 # else
  59 #  error "Both CONFIG_ENV_SECT_SIZE and CONFIG_ENV_SIZE undefined"
  60 # endif
  61 # if defined(CONFIG_ENV_ADDR_REDUND) && !defined(CONFIG_ENV_SIZE_REDUND)
  62 #  define CONFIG_ENV_SIZE_REDUND        CONFIG_ENV_SIZE
  63 # endif
  64 # if    (CONFIG_ENV_ADDR >= CONFIG_SYS_MONITOR_BASE) &&         \
  65         (CONFIG_ENV_ADDR + CONFIG_ENV_SIZE) <=                  \
  66         (CONFIG_SYS_MONITOR_BASE + CONFIG_SYS_MONITOR_LEN)
  67 #  define ENV_IS_EMBEDDED
  68 # endif
  69 # if defined(CONFIG_ENV_ADDR_REDUND) || defined(CONFIG_ENV_OFFSET_REDUND)
  70 #  define CONFIG_SYS_REDUNDAND_ENVIRONMENT
  71 # endif
  72 # ifdef CONFIG_ENV_IS_EMBEDDED
  73 #  error "do not define CONFIG_ENV_IS_EMBEDDED in your board config"
  74 #  error "it is calculated automatically for you"
  75 # endif
  76 #endif  /* CONFIG_ENV_IS_IN_FLASH */
  77
  78 #if defined(CONFIG_ENV_IS_IN_NAND)
  79 # if defined(CONFIG_ENV_OFFSET_OOB)
  80 #  ifdef CONFIG_ENV_OFFSET_REDUND
  81 #   error "CONFIG_ENV_OFFSET_REDUND is not supported when CONFIG_ENV_OFFSET_OOB"
  82 #   error "is set"
  83 #  endif
  84 extern unsigned long nand_env_oob_offset;
  85 #  define CONFIG_ENV_OFFSET nand_env_oob_offset
  86 # else
  87 #  ifndef CONFIG_ENV_OFFSET
  88 #   error "Need to define CONFIG_ENV_OFFSET when using CONFIG_ENV_IS_IN_NAND"
  89 #  endif
  90 #  ifdef CONFIG_ENV_OFFSET_REDUND
  91 #   define CONFIG_SYS_REDUNDAND_ENVIRONMENT
  92 #  endif
  93 # endif /* CONFIG_ENV_OFFSET_OOB */
  94 # ifndef CONFIG_ENV_SIZE
  95 #  error "Need to define CONFIG_ENV_SIZE when using CONFIG_ENV_IS_IN_NAND"
  96 # endif
  97 #endif /* CONFIG_ENV_IS_IN_NAND */
  98
  99 /* Embedded env is only supported for some flash types */
 100 #ifdef CONFIG_ENV_IS_EMBEDDED
 101 # if    !defined(CONFIG_ENV_IS_IN_FLASH)        && \
 102         !defined(CONFIG_ENV_IS_IN_NAND)         && \
 103         !defined(CONFIG_ENV_IS_IN_ONENAND)      && \
 104         !defined(CONFIG_ENV_IS_IN_SPI_FLASH)
 105 #  error "CONFIG_ENV_IS_EMBEDDED not supported for your flash type"
 106 # endif
 107 #endif
 108
 109 /*
 110  * For the flash types where embedded env is supported, but it cannot be
 111  * calculated automatically (i.e. NAND), take the board opt-in.
 112  */
 113 #if defined(CONFIG_ENV_IS_EMBEDDED) && !defined(ENV_IS_EMBEDDED)
 114 # define ENV_IS_EMBEDDED
 115 #endif
 116
 117 /* The build system likes to know if the env is embedded */
 118 #ifdef DO_DEPS_ONLY
 119 # ifdef ENV_IS_EMBEDDED
 120 #  ifndef CONFIG_ENV_IS_EMBEDDED
 121 #   define CONFIG_ENV_IS_EMBEDDED
 122 #  endif
 123 # endif
 124 #endif
 125
 126 #include "compiler.h"
 127
 128 #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
 129 # define ENV_HEADER_SIZE        (sizeof(uint32_t) + 1)
 130
 131 # define ACTIVE_FLAG   1
 132 # define OBSOLETE_FLAG 0
 133 #else
 134 # define ENV_HEADER_SIZE        (sizeof(uint32_t))
 135 #endif
 136
 137 #if defined(CONFIG_CMD_SAVEENV) && !defined(CONFIG_ENV_IS_NOWHERE)
 138 extern char *env_name_spec;
 139 #endif
 140
 141 #define ENV_SIZE (CONFIG_ENV_SIZE - ENV_HEADER_SIZE)
 142
 143 typedef struct environment_s {
 144         uint32_t        crc;            /* CRC32 over data bytes        */
 145 #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
 146         unsigned char   flags;          /* active/obsolete flags        */
 147 #endif
 148         unsigned char   data[ENV_SIZE]; /* Environment data             */
 149 } env_t;
 150
 151 #ifdef ENV_IS_EMBEDDED
 152 extern env_t environment;
 153 #endif /* ENV_IS_EMBEDDED */
 154
 155 extern const unsigned char default_environment[];
 156 extern env_t *env_ptr;
 157
 158 extern void env_relocate_spec(void);
 159 extern unsigned char env_get_char_spec(int);
 160
 161 #if defined(CONFIG_NEEDS_MANUAL_RELOC)
 162 extern void env_reloc(void);
 163 #endif
 164
 165 #ifndef DO_DEPS_ONLY
 166
 167 #include <search.h>
 168
 169 extern struct hsearch_data env_htab;
 170
 171 /* Function that returns a character from the environment */
 172 unsigned char env_get_char(int);
 173
 174 /* Function that returns a pointer to a value from the environment */
 175 const unsigned char *env_get_addr(int);
 176 unsigned char env_get_char_memory(int index);
 177
 178 /* Function that updates CRC of the enironment */
 179 void env_crc_update(void);
 180
 181 /* [re]set to the default environment */
 182 void set_default_env(const char *s);
 183
 184 /* [re]set individual variables to their value in the default environment */
 185 int set_default_vars(int nvars, char * const vars[]);
 186
 187 /* Import from binary representation into hash table */
 188 int env_import(const char *buf, int check);
 189
 190 /*
 191  * Check if variable "name" can be changed from oldval to newval,
 192  * and if so, apply the changes (e.g. baudrate).
 193  * When (flag & H_FORCE) is set, it does not print out any error
 194  * message and forces overwriting of write-once variables.
 195  */
 196 int env_check_apply(const char *name, const char *oldval,
 197                         const char *newval, int flag);
 198
 199 #endif /* DO_DEPS_ONLY */
 200
 201 #endif /* _ENVIRONMENT_H_ */