[U-Boot] Block/Disable U-Boot Console Access

[Alan Kash]

Hi,

I am an application software guy learning low-level embedded programming.

I am trying to block/disable u-boot console access all together. Is there
any helpful documentation for this topic.

The things I gathered until now:

1. Disable Serial Port pins.
Question - If an attacker gains root access, can he reconfigure serial port
pins to re-enable this ? How can we disable serial port access at the
hardware level ?

2. Enable "silent" & bootdelay=0 environment variables.
3. Enable password protection of U-Boot console.
4. Encrypt "Environment Memory Block"

in case of *any* hardware interruptions, the u-boot opens the console. Can
we disable this behavior to stop the device unless a power recycle happens
or start the boot process again.


I appreciate any general comments on this topic.

Thanks,
Alan