FYI: Merge in progress...

Eric W. Biederman ebiederman at
Wed Oct 20 21:52:01 CEST 2004

YhLu <YhLu at> writes:

> Amd_early_mtrr.c

Ok. I will agree that disable_cache in amd_early_mtrr is overkill
and remove that.  Since the wbinvd seems to be necessary in the
general disable_cache case.

I am leery about not reusing code between the various versions
of mtrr setup because that causes behaviour skew.

It actually is not appropriate to enable cache of memory until
we have enabled it.  You don't see that on an Opteron but
it is trivial to see on a Xeon, and that has been a bug that
has been waiting to hit us for a while.  CPU prefetch units
can cause amazing problems.

As for messing with RdDram and WrDram extension bits we are not
using the fixed mtrrs at this point and I fee that is better
a question left up cpu initialization code to handle later.
Hmm.  We don't actually handle it later either so I have just
added that code, there.    That way everything should be all in
one place.

Thanks for the code review.


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