[U-Boot] Kernel to U-boot messaging and vice versa.

[Andy Pont]

Dev wrote...

> I am new to U-boot development. We are using U-Boot 1.1.4 on a MIPS
> 74Kc QCA 9557 processor, which is running Linux Kernel 2.6.32.27. 

Is there a reason why you have to be running a kernel from 2010 and a
version of bootloader that is even older?  It makes life much easier to
provide support if you can update to more recent versions and you never know
they may already have fixed your problems!

> We have a situation were our firmware keeps hanging due to some issues. 

What is your "firmware" in this context?  As you rightly said, once the
Linux kernel is running U-Boot is no more and if U-Boot is hanging then you
aren't going to get to the kernel anyway!

> We are looking into a solution where U-boot and Kernel keep communicating
> with each other every some minutes. If U-boot finds that there is no
> communication, it will reset the board.

This sounds like it is the territory of watchdog timers.  I don't know that
CPU to know whether it has one built in though, nor if the kernel supports
it.

Andy.