[U-Boot-Users] boot control concept

[Andrew Wozniak]

Hello everyone,

Our ppc440gx-based project needs to develop a "boot control" mechanism
without any operator intervention. We have a customer PCI interface
where "special jumper settings" will indicate if an OS should be booted
from Flash or via TFTP.

We also desire that once U-Boot has been installed in Flash, the user
will ONLY be allowed to update OS and application components. This
insures that the user can always get to the U-Boot prompt in case they
somehow corrupted the Flash. We don't want to embed our code within
U-Boot because our code needs to be field upgradeable.

I was hoping to construct a U-Boot application (similar to hello_world
example) and do all of our "boot control" processing their. This
application would configure U-Boot to boot in one of the desired modes
based on special jumper settings.

It seems there are several ways to perform this. This app could use
native U-Boot calls to setup the environment before returning to U-Boot
where the OS load/boot would be completed. Would this work or is their a
better approach?

I've looked thru the docs and email list and have not seen anything done
like this. Any observations and suggestions about this are very welcome.

Thanks and best regards