But he normally does call by 12 but he hasn't yet. Should I call him?

I don't think it's good to talk to someone out of habit or just because it's a certain time of the day... you should call him if you really want to talk to him, but not simply because he hasn't yet.

It would also make sense that he's busy if this really is a thing he does everyday. So it may be worth just waiting for a while anyway.