src/mainboard/apple/macbookair4_2/Makefile.inc - coreboot - Gitiles

 romstage-y += early_southbridge.c
 romstage-y += gpio.c
 ramstage-y += gnvs.c

 cbfs-files-y += spd.bin
 spd.bin-file := spd.bin
 spd.bin-type := spd
	romstage-y += early_southbridge.c
	romstage-y += gpio.c
	ramstage-y += gnvs.c

	cbfs-files-y += spd.bin
	spd.bin-file := spd.bin
	spd.bin-type := spd