GDB with PCIe device

Hello,

As per my understanding, gdb calls ptrace system calls which intern uses
kernel implementation of architecture specific action (updating debug
registers,reading context memory...) to set breakpoints, and so on.

But in case of running gdb with PCIe devices such as gpu or fpga, how does
the hardware specific actions are being done?

Should device drivers provide ptrace equivalent kernel implementation?

 Could any of the gdb gurus shed some light on debug software stacks in
debugging software that runs on one of the mentioned pcie devices?

Thanks in advance,