I have here a Guruplug that doesn't boot any more. With the help of the JTAG-debugger, I have figured out that the processor doesn't jump to the U-Boot start address 0x00600000. Furthermore, it remains in an endless loop at address 0xffff0b2e:
target state: halted
target halted in Thumb state due to debug-request, current mode: Supervisor
cpsr: 0x400000f3 pc: 0xffff0b2e
But when I load the U-Boot over an OpenOCD-session and execute 'resume 0x00600000', the bootloader starts as expected. Now, my question: does somebody knows how to solve this problem? Thanks in advance.