In the current codebase the NPU driver does not need to access the WiFi PCIe
slot (or any other external device) since the offloading (wired and wireless)
is fully managed by the NPU chip (hw + firmware binaries).

Are you saying the NPU itself enumerates the PCI busses and finds the
WiFi device?  If it can do that, why not ask it which PCI device it is
using?

Or this the PCI slot to use somehow embedded within the firmware?

Or is it simply hard coded in the NPU silicon which slot to use?

   Andrew