Navio2 STM32 ARM firmware source code availability?

Is there a firmware source code for Navio2 available for download or clone from git?
Is it possible to update firmware on this processor?

Fair enough. Thanks for quick answer. One more question. Is there a way to upload your own code to the processor to fully utilize it’s processing potential? Is there ISP pinout available from Raspberry or for external programming tools?
Just asking because with closed design it may be impossible to do it anyway.

You can upload your code via SWD available on RPi header, here is the pinout:

Great. Thank you.

Is there possibility to get the ARM source code yet?