[LinuxBIOS] Does MA map type effect MRS values?

Segher Boessenkool segher at kernel.crashing.org
Wed Jul 11 18:29:12 CEST 2007

>>> Simple question that I can't seem to find the answer to  
>>> _anywhere_. From
>>> JEDEC's docs, it sounds like it should, but I can't figure out  
>>> what the
>>> relationship is. Any info would be greatly appreciated ;)
>> What is "MA map type"?  Are you talking about DDR1, DDR2,
>> DDR3, some GDDR, or what else, anyway?  :-)

> Sorry, Memory Address map type, in relation to the via cn700 (or  
> any via
> northbridge) and ddr2 ram. And the answer appears to be that it  
> doesn't,
> since the system is now working with either of two different MA map  
> type
> settings (yay!).

Ah, sounds like it just selects between two different kinds
of address interleaving.  Typically, one is best for random
access, and the other is best for accessing big blocks of

In the (E)MRS regs, you only need to set things like CL, AL,
and termination settings.  It's quite important to get those
right of course ;-)


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