[coreboot] Raminit help

Myles Watson mylesgw at gmail.com
Tue Jun 9 19:16:18 CEST 2009


> > set_var_mtrr(0, 0x08000000, 0x10000000, MTRR_TYPE_WRBACK);
> Hm.. doesn't the base address need at least an alignment of size?

Yes.  Thanks.

> Have you tried disabling caching completely for the area?

Not here, I did before.  I was hoping that caching would avoid the alignment
issues I've been seeing.
 
> > // Try to force the values out of the cache.
> If you are trying to avoid the accesses from being cached, they need to
> cross a cache line.

I wasn't trying to cross a cache line.  I was trying to write to the same
cache line enough times that it would force it to write it back.
 
> The above accesses would imho not cross a cache line, unless a cache
> line on opteron is as small as 8 byte, which I find hard to believe.

You're right.

Thanks,
Myles





More information about the coreboot mailing list