In message 36422.202.62.67.130.1113472528.squirrel@202.62.67.130 you wrote:
Here customer is asking to give provision to erase U-boot from Kernel as well as from existing U-boot when there is any updated U-Boot.
I'm sure you are aware of this risk, but I think I should point it out anyway: there is no fall-back or other means of recovery if updating U-boot fails. If you have a power-failure or if the customer poresses the reset button during this procedure, the your board is dead. Period.
Currently i am erasing U-Boot from U-Boot only. I do not know how to erase U-Boot from Kernel.
Then please go back and read the manual, especially here: http://www.denx.de/twiki/bin/view/DULG/UBootInstallUsingLinux
Here i have some fundamental doubts that , How to erase U-Boot from Kernel level?
Provide an appropriate MTD partitioning and use the standard MTD drivers.
How to access Physical address directly in Linux Kernel?
You don't want nor need to do this.
Best regards,
Wolfgang Denk