[coreboot] H8QME-2+ boot problems on different machines.

Myles Watson mylesgw at gmail.com
Wed May 5 16:44:13 CEST 2010

I've had questions about resource maps too.

> > - I now know that my resource map must be some kind of faulty. But why
> > does it work on one CPU and doesn't on another, complete identical, one?
> It's not about the CPU, it is more about how the mainboard is wired
> up. And, it is not surprising that it might be wired differently
> on two mainboards with identical part #s. Supermicro does this type of
> change frequently. You would really need to boot the factory
> bios and dump the config registers on all cpus to see if they
> mainboard has changed somehow.

The reason he got to that conclusion was that the same motherboard boots
differently with a different CPU and the identical BIOS.  I don't understand
how it could be a wiring issue.

If the failure is consistent, can you use showallroutes(BIOS_INFO,
PCI_DEV(0, 0x18, 1)); right before your resource map gets set.  I think that
might help us figure it out.
> > - How do i manage to correct my resource map? Or how do I create a good
> > resource map?
> dump the factory bios.

I think this can be problematic, since by the time you can dump the factory
BIOS resource allocation has already occurred.  The resource map is only
good for early initialization, before resource allocation, right?

> > - Since it seems to boot fine without resource map. Do I really need
> one?
I think the problem comes if values happen to be left over from a previous
boot.  I guess it could happen with different "default" values for different
processors, too.  Then devices that should be reachable won't respond.
> you really need one.
> > - And the last one, If I don't setup the res. map, who does it?
> nobody.

At least until resource allocation.


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