Well, you just look at the memory location of physw_status. Its base address is in stubs_min.S, yours reads:
DEF(physw_status, 0x564B0) // find in "PhySw"
So, you want to examine 0x564B0, 0x564B4, and 0x564B8. In Debug/Mem. browser, you step through the memory with left-right, change the step with Disp. The display is not updated in real time, so to see a change, you have to step up then back down.
Edit: Wait, you say "4: 0 / 1 changes if i plug in and out an active usb/hub". But that means it works as it should! So check your remote. Maybe 3V is not enough.