FreeRTOS on ZCU106 hangs early

Kernel
1

Hi everyone!

I need to port a FreeRTOS application to ZCU106 (from TE Zynq7).
I am on V10.2.1 and working in Vivado+SDK 2019.1.

Now when I try to debug the application it doesnt halt on the breakpoint in main.
When I manually halt, I can see that I am in FreeRTOS_asm_vectors.S on
.org (VBAR + 0x200)
b .
where obviously the application can’t get out of.
I got the linker script and FreeRTOS config from the example (cortex A53 on ZCU102).
I might need to add, that my application only compiles with the -z muldefs linker flag, which I am not used to from the Zynq7 projects.

I don’t really know how to approach this, so all hints are welcome.

EDIT: I just tested the builtin FreeRTOS hello world example and I get the same behaviour.

2

you can not rely on breakpoints set by your debugger to be where you expect them to be due to little correlation between source and assembly code. You may want to either compule unoptimized or insert a breakpoint hard coded (eg __asm(“bkpt”)) just to see if thar is your problem.

3

Thanks @RAc.
I was landing on that program address because of system fault:
I have just learned that Cortex A53 resets to exception level 3, where you can’t run your FreeRTOS application.
An FSBL needs to run before the application, that pulls the core to EL1.
Only then the application can start running (in EL3 the core will through the mentioned system error causing the program to branch to said address where it lands in an infinite loop).