[U-Boot] user-space ===>> U-Boot ====>> user-space ?

[Swarthout Edward L-SWARTHOU]

From: bosmith
> 
> ...
> The use-case is to have two kernel images, two root file 
> systems, and to let a user-space application specify which to 
> use and then force a reboot.  The system will not lose power 
> during this reboot.
> 
> This seems like a common enough problem.  Has anyone solved it before?

This sort of image swapping in flash is best done with some 
support from board logic.

For example, the FSL mpc85xx boards have a register that a user can
write 
that inverts a high-order flash address bit.  Inverting this bit
causes the next boot to access the alternate bank.

This allows simple bank switching with no modification to any code.

Ed