Has anybody "worked out" where God came from?

If God can exist without being created, why not the Cosmos itself?

How do we know that the totality of all the elements and energy that exist required creation? And if they did, why doesn't God require having been created? And if He does, where did he come from? But if He always existed, why can't that be just as true of all that exists?

The difference between the idea of an eternal Cosmos and the idea of an eternal God is that God cares about you, and the Cosmos couldn't care less.

(The Greek and Roman gods cared about people too, but that was definitely a mixed blessing.)