README 1.8 KB

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  1. This is a demo implementation of a Linux command line tool to access
  2. the U-Boot's environment variables.
  3. For the run-time utiltity configuration uncomment the line
  4. #define CONFIG_FILE "/etc/fw_env.config"
  5. in fw_env.h.
  6. For building against older versions of the MTD headers (meaning before
  7. v2.6.8-rc1) it is required to pass the argument "MTD_VERSION=old" to
  8. make.
  9. See comments in the fw_env.config file for definitions for the
  10. particular board.
  11. Configuration can also be done via #defines in the fw_env.h file. The
  12. following lines are relevant:
  13. #define HAVE_REDUND /* For systems with 2 env sectors */
  14. #define DEVICE1_NAME "/dev/mtd1"
  15. #define DEVICE2_NAME "/dev/mtd2"
  16. #define DEVICE1_OFFSET 0x0000
  17. #define ENV1_SIZE 0x4000
  18. #define DEVICE1_ESIZE 0x4000
  19. #define DEVICE1_ENVSECTORS 2
  20. #define DEVICE2_OFFSET 0x0000
  21. #define ENV2_SIZE 0x4000
  22. #define DEVICE2_ESIZE 0x4000
  23. #define DEVICE2_ENVSECTORS 2
  24. Current configuration matches the environment layout of the TRAB
  25. board.
  26. Un-define HAVE_REDUND, if you want to use the utlities on a system
  27. that does not have support for redundant environment enabled.
  28. If HAVE_REDUND is undefined, DEVICE2_NAME is ignored,
  29. as is ENV2_SIZE and DEVICE2_ESIZE.
  30. The DEVICEx_NAME constants define which MTD character devices are to
  31. be used to access the environment.
  32. The DEVICEx_OFFSET constants define the environment offset within the
  33. MTD character device.
  34. ENVx_SIZE defines the size in bytes taken by the environment, which
  35. may be less then flash sector size, if the environment takes less
  36. then 1 sector.
  37. DEVICEx_ESIZE defines the size of the first sector in the flash
  38. partition where the environment resides.
  39. DEVICEx_ENVSECTORS defines the number of sectors that may be used for
  40. this environment instance. On NAND this is used to limit the range
  41. within which bad blocks are skipped, on NOR it is not used.