Freeze during booting of ASUS F2A85-M motherboard with Coreboot

I'm trying to boot the ASUS F2A85-M board with flashed Coreboot 4.4 and
SeaBIOS 1.9.1 as a payload.

This board works nicely with stock UEFI, it can also boot Slackware 14.2
from Coreboot with SeaBIOS without any issues.

But it seems to have problems with FreeBSD (I've tried 11.0-RC3 and
later 12.0-CURRENT). That's why I'm posting it here, instead of Coreboot
mailing lists.

Booting freezes after printing:
pcib1: failed to allocate initial I/O port window: 0x1000-0x1fff

After that, I've waited for about 30 minutes. Nothing happened, altough
my DVD drive was spinning for a while, which may indicate that the OS
was actually booting, but without printing anything (I was booting from
DVD).

I use external NVIDIA GPU (GF GT650TI), which may matter.

Any ideas what I can do with it?

My Coreboot config is at:
http://cxg.de/_98b2f4.htm

SeaBIOS config:
http://cxg.de/_020d57.htm