Debug from reset vector

Hi,

I would like to debug my SoC with CortexA-53 core from the reset vector.

For this, I am writing the EDECR.RCE bit and does a warm reset.
The core is getting reset and halt at reset vector. The status is also found to be correct from the EDSCR register.
But i Am not able to properly debug the core afterwards. Ican read and write the registers. But cannot do the step operation.
Do I need to do any other initialization for this?

Regards,
Ranjith

Michael Williams