On Dec 15, 2011, at 9:26 PM, Kyle Moffett wrote:
This EEPROM is hardware-write-protected and used to persist key information such as the serial number and MAC addresses even if the primary environment sector in NOR FLASH is overwritten.
During manufacturing, the environment is initialized from Linux and then the key parameters copied to the EEPROM via U-Boot:
env export -c -s 0x2000 $loadaddr serial# macaddr mac1addr mac2addr eeprom write $loadaddr 0x0000 0x2000
The chip is then locked via hardware for delivery.
When doing a field U-Boot upgrade, the environment is erased and reset to the defaults to avoid problems with "hwconfig" changes, etc. After loading the new U-Boot image, the hardware data is reloaded:
i2c dev 0 eeprom read $loadaddr 0x0000 0x2000 env import -c $loadaddr 0x2000 saveenv
The first three commands are saved in the "restore_eeprom" variable for user convenience. (EG: "run restore_eeprom && saveenv")
Signed-off-by: Kyle Moffett Kyle.D.Moffett@boeing.com Cc: Andy Fleming afleming@gmail.com Cc: Kumar Gala kumar.gala@freescale.com
include/configs/HWW1U1A.h | 29 +++++++++++++++++++++++++++-- 1 files changed, 27 insertions(+), 2 deletions(-)
applied to 85xx
- k