Postponed/detached MII attachment?

Hi,

a week ago I tried to get some hint from hackers, no response there.
(Subject: Two devices created for one block in device tree?)

I have a board with SoC containing two MACs (cgem driver) plus two
PHYs, but MDIO bus controlling both PHYs is connected to second MAC.
Thus my problem is how can I attach miibus instance to first (cgem0)
driver after second one (cgem1) is initialized.

As noted in my mail mentioned above, I am aware of miiproxy device,
which should be basically the solution. It is used only for arge driver
in official FreeBSD src tree, which uses hints, while I need FDT based
device tree.

Could anybody offer any hint, pointer, assistance? I am trying to get
somewhere, but all my attempts do not yield usable resuld, yet.

Regards,
Milan