[coreboot] [PATCH try 4] Reduce duplicate definition in CAR code.

Kevin O'Connor kevin at koconnor.net
Fri Oct 8 02:13:36 CEST 2010


On Thu, Oct 07, 2010 at 09:16:28AM -0700, Stefan Reinauer wrote:
>  On 10/7/10 5:58 AM, Kevin O'Connor wrote:
> > BTW, the list concept doesn't make much sense anyway - at least on
> > Via, there is no need to clear the fixed mtrrs, and you don't need a
> > list to clear the variable mtrrs (a simple iterator would suffice).
> The list seemed more comprehensible than writing down linear code. It's
> simple for the variable mtrrs, but the fixed ones are not linearly spread.
> 
> Why do you assume it's not needed to clear the fixed MTRRs on VIA
> systems? I don't think we should assume they didn't get set to "bad"
> values by the OS running prior to a reset, for example.

The via code runs with fixed mtrrs disabled in MTRRdefType_MSR.  (It
writes 0x800 there instead of 0xc00.)  Because fixed MTRRs aren't
enabled during CAR, they don't need to be cleared in the CAR setup
phase.

-Kevin




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