Debug pixhawk with st-linkv2 and jtag jlink-8

I already read the most part of internet docs and manuals of debugging STM32 with eclipse using STLINK or JTAB GDB, or with Qt creator but no information if is it real to debug ardupilot code on real pixhawk with brakepoints etc.

I have seen black magic probe and find on pixhawk contact pads for jtag interface and or stlink interface, I have stm32f4discovery and debug it from eclipse very well, pixhawk have stm32f429 processor so How Can I debug it step by step with break points.
After build code in linux with make i have elf and .px4 files but what is next???

Help me pleeeeeeeeeeeeeese from me good bear ;))
thank you for your advice

hey do you have some solutoin?