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(CFG_ENV_IS_IN_FLASH)
  41 # ifndef  CFG_ENV_ADDR
  42 #  define CFG_ENV_ADDR  (CFG_FLASH_BASE + CFG_ENV_OFFSET)
  43 # endif
  44 # ifndef  CFG_ENV_OFFSET
  45 #  define CFG_ENV_OFFSET (CFG_ENV_ADDR - CFG_FLASH_BASE)
  46 # endif
  47 # if !defined(CFG_ENV_ADDR_REDUND) && defined(CFG_ENV_OFFSET_REDUND)
  48 #  define CFG_ENV_ADDR_REDUND   (CFG_FLASH_BASE + CFG_ENV_OFFSET_REDUND)
  49 # endif
  50 # if defined(CFG_ENV_SECT_SIZE) || defined(CFG_ENV_SIZE)
  51 #  ifndef  CFG_ENV_SECT_SIZE
  52 #   define CFG_ENV_SECT_SIZE    CFG_ENV_SIZE
  53 #  endif
  54 #  ifndef  CFG_ENV_SIZE
  55 #   define CFG_ENV_SIZE CFG_ENV_SECT_SIZE
  56 #  endif
  57 # else
  58 #  error "Both CFG_ENV_SECT_SIZE and CFG_ENV_SIZE undefined"
  59 # endif
  60 # if defined(CFG_ENV_ADDR_REDUND) && !defined(CFG_ENV_SIZE_REDUND)
  61 #  define CFG_ENV_SIZE_REDUND   CFG_ENV_SIZE
  62 # endif
  63 # if (CFG_ENV_ADDR >= CFG_MONITOR_BASE) && \
  64      (CFG_ENV_ADDR+CFG_ENV_SIZE) <= (CFG_MONITOR_BASE + CFG_MONITOR_LEN)
  65 #  define ENV_IS_EMBEDDED       1
  66 # endif
  67 # if defined(CFG_ENV_ADDR_REDUND) || defined(CFG_ENV_OFFSET_REDUND)
  68 #  define CFG_REDUNDAND_ENVIRONMENT     1
  69 # endif
  70 #endif  /* CFG_ENV_IS_IN_FLASH */
  71
  72 #if defined(CFG_ENV_IS_IN_NAND)
  73 #if defined(CFG_ENV_OFFSET_PATCHED) || defined(CFG_ENV_OFFSET_OOB)
  74 extern unsigned long env_offset;
  75 #define CFG_ENV_OFFSET env_offset
  76 #else
  77 # ifndef CFG_ENV_OFFSET
  78 #  error "Need to define CFG_ENV_OFFSET when using CFG_ENV_IS_IN_NAND"
  79 # endif
  80 # ifndef CFG_ENV_SIZE
  81 #  error "Need to define CFG_ENV_SIZE when using CFG_ENV_IS_IN_NAND"
  82 # endif
  83 # ifdef CFG_ENV_OFFSET_REDUND
  84 #  define CFG_REDUNDAND_ENVIRONMENT
  85 # endif
  86 # ifdef CFG_ENV_IS_EMBEDDED
  87 #  define ENV_IS_EMBEDDED       1
  88 # endif
  89 #endif /* CFG_ENV_NAND_PATCHED */
  90 #endif /* CFG_ENV_IS_IN_NAND */
  91
  92
  93 #ifdef CFG_REDUNDAND_ENVIRONMENT
  94 # define ENV_HEADER_SIZE        (sizeof(unsigned long) + 1)
  95 #else
  96 # define ENV_HEADER_SIZE        (sizeof(unsigned long))
  97 #endif
  98
  99
 100 #define ENV_SIZE (CFG_ENV_SIZE - ENV_HEADER_SIZE)
 101
 102 typedef struct environment_s {
 103         unsigned long   crc;            /* CRC32 over data bytes        */
 104 #ifdef CFG_REDUNDAND_ENVIRONMENT
 105         unsigned char   flags;          /* active/obsolete flags        */
 106 #endif
 107         unsigned char   data[ENV_SIZE]; /* Environment data             */
 108 } env_t;
 109
 110
 111 void default_env(void);
 112
 113 #endif  /* _ENVIRONMENT_H_ */