[coreboot] AGESA (f15tn) AmdInitReset doing nasty things

[mrnuke]

It's changing the ROM base (devfn 14.3, register 0x6c) from 0xffc0 to 0xff00. 
The bootblock sets it up correctly, but AmdInitReset messes it up.

Any ideas? AGESA is particularly annoying to grep.

Alex