Hi. I succeeded in going build a FILO 0.6.0 in this way: http://yohann.martineau.free.fr/blog.php?lang=fr&url=boot-coreboot--filo-and-a-tiny-debian only change svn to actual git coreboot link :-)
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                     FILO 0.6.0, coreboot: 4.0-4772-ga4affe1-dirty

                               root_dev = unset

 [ Minimal BASH-like line editing is supported.  For the first word, TAB

   lists possible command completions.]

 

filo> probe

ata0 master [ATA DISK]: Maxtor 2F020J0

ATA-1: [io ports 0x170-0x177,0x376]

* hdc [ATAPI CD-ROM]: OEM CD-ROM F563E

ata1 master [ATAPI CDROM/DVD]: OEM CD-ROM F563E

IDE channel 2 not found

IDE channel 2 not found

IDE channel 3 not found

IDE channel 3 not found

filo>