[coreboot] which mainboard is the best reference for s3

Hi Rudolf	,
I want to update my vx855 code using the newest version of coreboot-v2,
to take advantage of new functions(such as smi,AML-auto-generator) that
appear on coreboot in the last months.

And, since I also want to use as much of coreboot's existing code as
possible(and to maintain a source that is not on coreboot's svn as easy
as possible...), I wonder which mainboard is the best reference for S3
function for now?

It seems that amdk8 now has good support of S3, but I didn't found S3
code on asus/m2v-mx_se.

Many thanks.

-jasonzhao