[coreboot] Geode GX2 CAR.

Nils njacobs8 at hetnet.nl
Sun Jun 20 23:42:29 CEST 2010

Hi all,
I ported the Geode LX Cache As Ram code to GX2.
It works nice and it reduces the boot time with ~35 seconds.
Though there is a piece of code i would like some more information on. 
It is in /src/northbridge/amd/lx/raminit.c :

/* SWAPSiF for PBZ 4112 (Errata 34) */
/* check for failed DLL settings now that we have done a memory write. */
	msr = rdmsr(msrnum);
	if ((msr.lo & 0x7FF) == 0x104) {

/* If you had it you would need to clear out the fail boot count flag */
/*       (depending on where it counts from etc). */

/* The reset we are about to perform clears the PM_SSC register in the */
/*       5536 so will need to store the S3 resume flag in NVRAM otherwise */
/*       it would do a normal boot */

		/* Reset the system */
		msrnum = MDD_SOFT_RESET;
		msr = rdmsr(msrnum);
		msr.lo |= 1;
		wrmsr(msrnum, msr);

 I omitted this routine in my patch because i could not find a description 
about PBZ 4112 (Errata 34) and according to the LX databook the tested bit 8
is "Reserved".

My questions are:
1. Where could i find information on "Errata 34" ?
2.Would a similar test be needed/desired for GX2 ?


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