Hi, (sorry, trying to reply old thread)
I'm runinng coreboot 4.7 without any problems on OpenBSD. I have compiled 4.9 and master and both have the same problem for the hci devices. On GNU/Linux I have experience inestability and lock ups.
I'm running with full ME.
Something must have be broken between 4.7 and 4.9 (I haven't been able to build 4.8.1, still trying).
Hope someone has any solution or knowns what is happening.