[U-Boot] ## Application terminated, rc = 0x1

[ba_f]

Hello U-Boot Crew,


i want to boot a little kernel on ARM Cortex a9.

But the kernel crushes pretty early with the following u-boot output:

## Starting application at 0x01000000 ...
## Application terminated, rc = 0x1

Since i have no clue where (and how) to start debugging, my first 
question is:

What may cause "Application terminated, rc = 0x1"?

I don't think it is a regular code exit, like main(){ return 1; }.

There must be any other issue.
But how to find out what's wrong?


Please, any advice for debugging, or any hint about what may cause 
rc=0x1 is welcome.



Thanks