Is there a Software initiated way to do P Channel handshake to Off State for NI-700?

We have a SoC with NI-700 interconnect.  We have a case where we want CPU on the completer side to complete the P-Chan handshake before it lets the power domain go down , due to a race condition in clocking.

How can I implement "Upstream power domain ON, downstream power domain ON→OFF" kind of handshake in FW? Is it using IDM Access Control register?