AA vs. all in on the flop

[DcifrThs]

i have 2.5k villian has me covered. haven't seen much from him but seems to be a tight player who opens for a standard amount between 70 and 80 when he opens.

im directly to his right and cold call his 70 opener with AA, a few more soles come a long for the ride and its 5 way to the flop w/ 1 blind.

flop is 9c6d3s checked to opener who betspot, i make it 900, folded back around to him he pushes.

action?, what does villian have here?

Barron