APU slave core issue.

Hello,

We are facing APU core 1,2 and 3 crashing when they are starting to execute after power on test. Here is the test scenario.

1: All APU cores (0 to 3) are running BIT test in SSBL in 64 bit mode and on BIT test completion APU core 1 to 3 are put into power on reset state. 

2: APU core 0 will handoff to another OS which is running in 32 bit mode and during 32 bit mode boot process, APU core 1 to 3 are put into execution state from power on reset state.

3: The moment APU core 1 to 3 are put into execution state, all cores are crashing.

What could be the reason for it?

I gave a delay in miliseconds (200 to 500) before putting core 1 to 3 into power on state in SSBL which fixes the issue. Not sure why with delay it is working.

can anyone help me on this? If more info required let me know, I will try to provide.

Thanks.