I would suggest you use the dumpnorth code in: src/bios/freebios/src/ram/dump_northbridge.inc
and check each step of your northbridge configuration.
To do this, in your config you will have this in your config: mainboardinit ram/dump_northbridge.inc
To use it:
CALLSP(dumpnorth)
at various places.
the file src/bios/freebios/src/northbridge/intel/430tx/raminit.inc shows some uses of this function. We found it very handy for getting that part up.
ron