Where does “Ἴ̄λιον” come from?

Ἴ̄λιον (Ancient Greek) comes from Hittite ??? — Wilusa; {{w|Wilusa}}.

Ancestry of “Ἴ̄λιον”, step by step

Step	Language	Word	Meaning
1	Hittite	???	Wilusa; {{w\|Wilusa}}