Always On AG cluster with 2 servers that fail over to each other I have 2 servers. One is dedicated as an OLTP server and the other will be a DW server. The OLTP server will have our application DB on it and our DW will have a couple of databases on it used for reporting. I would like to cluster them and build an AG for our OLTP DB that will failover to the DW server and provide the DW with a read-only replica for reporting. By the same token I would like to build the 2 DW databases into an AG and have them failover to the OLTP instance strictly for fault tolerance even though they technically could be read only replicas there as well. Is this possible? I need fault tolerance, I need the read-only replica for reporting and I need some fault tolerance for the DW too and I only have 2 servers and Enterprise licensing for those 2 servers.  Thanks!
Yes, this is absolutely possible, and a great use of resources. 

You would get your OLTP databases added to an Availability Group, and then add the second machine as your secondary replica. For both replicas be sure to allow reads from secondary.

Then do the same with your DW databases.

You will end up with two AGs, and will probably want to run with each as the primary on different servers, so be sure that you include monitoring to let you know when the AGs failover, and what AG is running as the primary on each server.