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_ 1
  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        (CONFIG_SYS_FLASH_BASE + CONFIG_ENV_OFFSET_REDUND)
  49 # endif
  50 # if defined(CONFIG_ENV_SECT_SIZE) || defined(CONFIG_ENV_SIZE)
  51 #  ifndef  CONFIG_ENV_SECT_SIZE
  52 #   define CONFIG_ENV_SECT_SIZE CONFIG_ENV_SIZE
  53 #  endif
  54 #  ifndef  CONFIG_ENV_SIZE
  55 #   define CONFIG_ENV_SIZE      CONFIG_ENV_SECT_SIZE
  56 #  endif
  57 # else
  58 #  error "Both CONFIG_ENV_SECT_SIZE and CONFIG_ENV_SIZE undefined"
  59 # endif
  60 # if defined(CONFIG_ENV_ADDR_REDUND) && !defined(CONFIG_ENV_SIZE_REDUND)
  61 #  define CONFIG_ENV_SIZE_REDUND        CONFIG_ENV_SIZE
  62 # endif
  63 # if (CONFIG_ENV_ADDR >= CONFIG_SYS_MONITOR_BASE) && \
  64      (CONFIG_ENV_ADDR+CONFIG_ENV_SIZE) <= (CONFIG_SYS_MONITOR_BASE + CONFIG_SYS_MONITOR_LEN)
  65 #  define ENV_IS_EMBEDDED       1
  66 # endif
  67 # if defined(CONFIG_ENV_ADDR_REDUND) || defined(CONFIG_ENV_OFFSET_REDUND)
  68 #  define CONFIG_SYS_REDUNDAND_ENVIRONMENT      1
  69 # endif
  70 # ifdef CONFIG_ENV_IS_EMBEDDED
  71 #  error "do not define CONFIG_ENV_IS_EMBEDDED in your board config"
  72 #  error "it is calculated automatically for you"
  73 # endif
  74 #endif  /* CONFIG_ENV_IS_IN_FLASH */
  75
  76 #if defined(CONFIG_ENV_IS_IN_NAND)
  77 # if defined(CONFIG_ENV_OFFSET_OOB)
  78 #  ifdef CONFIG_ENV_OFFSET_REDUND
  79 #   error "CONFIG_ENV_OFFSET_REDUND is not supported when CONFIG_ENV_OFFSET_OOB"
  80 #   error "is set"
  81 #  endif
  82 extern unsigned long nand_env_oob_offset;
  83 #  define CONFIG_ENV_OFFSET nand_env_oob_offset
  84 # else
  85 #  ifndef CONFIG_ENV_OFFSET
  86 #   error "Need to define CONFIG_ENV_OFFSET when using CONFIG_ENV_IS_IN_NAND"
  87 #  endif
  88 #  ifdef CONFIG_ENV_OFFSET_REDUND
  89 #   define CONFIG_SYS_REDUNDAND_ENVIRONMENT
  90 #  endif
  91 # endif /* CONFIG_ENV_OFFSET_OOB */
  92 # ifndef CONFIG_ENV_SIZE
  93 #  error "Need to define CONFIG_ENV_SIZE when using CONFIG_ENV_IS_IN_NAND"
  94 # endif
  95 #endif /* CONFIG_ENV_IS_IN_NAND */
  96
  97 #if defined(CONFIG_ENV_IS_IN_MG_DISK)
  98 # ifndef CONFIG_ENV_ADDR
  99 #  error "Need to define CONFIG_ENV_ADDR when using CONFIG_ENV_IS_IN_MG_DISK"
 100 # endif
 101 # ifndef CONFIG_ENV_SIZE
 102 #  error "Need to define CONFIG_ENV_SIZE when using CONFIG_ENV_IS_IN_MG_DISK"
 103 # endif
 104 #endif /* CONFIG_ENV_IS_IN_MG_DISK */
 105
 106 /* Embedded env is only supported for some flash types */
 107 #ifdef CONFIG_ENV_IS_EMBEDDED
 108 # if !defined(CONFIG_ENV_IS_IN_FLASH) && \
 109      !defined(CONFIG_ENV_IS_IN_NAND) && \
 110      !defined(CONFIG_ENV_IS_IN_ONENAND)
 111 #  error "CONFIG_ENV_IS_EMBEDDED not supported for your flash type"
 112 # endif
 113 #endif
 114
 115 /*
 116  * For the flash types where embedded env is supported, but it cannot be
 117  * calculated automatically (i.e. NAND), take the board opt-in.
 118  */
 119 #if defined(CONFIG_ENV_IS_EMBEDDED) && !defined(ENV_IS_EMBEDDED)
 120 # define ENV_IS_EMBEDDED 1
 121 #endif
 122
 123 /* The build system likes to know if the env is embedded */
 124 #ifdef DO_DEPS_ONLY
 125 # ifdef ENV_IS_EMBEDDED
 126 #  define CONFIG_ENV_IS_EMBEDDED
 127 # endif
 128 #endif
 129
 130 #include "compiler.h"
 131
 132 #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
 133 # define ENV_HEADER_SIZE        (sizeof(uint32_t) + 1)
 134
 135 # define ACTIVE_FLAG   1
 136 # define OBSOLETE_FLAG 0
 137 #else
 138 # define ENV_HEADER_SIZE        (sizeof(uint32_t))
 139 #endif
 140
 141
 142 #define ENV_SIZE (CONFIG_ENV_SIZE - ENV_HEADER_SIZE)
 143
 144 typedef struct environment_s {
 145         uint32_t        crc;            /* CRC32 over data bytes        */
 146 #ifdef CONFIG_SYS_REDUNDAND_ENVIRONMENT
 147         unsigned char   flags;          /* active/obsolete flags        */
 148 #endif
 149         unsigned char   data[ENV_SIZE]; /* Environment data             */
 150 } env_t;
 151
 152 /* Function that returns a character from the environment */
 153 unsigned char env_get_char (int);
 154
 155 /* Function that returns a pointer to a value from the environment */
 156 unsigned char *env_get_addr(int);
 157 unsigned char env_get_char_memory (int index);
 158
 159 /* Function that updates CRC of the enironment */
 160 void env_crc_update (void);
 161
 162 /* [re]set to the default environment */
 163 void set_default_env(void);
 164
 165 #endif  /* _ENVIRONMENT_H_ */