Non-tristate cfi flash component in sopc

You can multiplex/demultiplex the cfi bus outside the SOPC system, using the read/write signal to detect the direction of the connexion you make.

A nicer solution would be to have your user logic inside the SOPC system, with an Avalon master interface to access the flash. That way, arbitration between your logic and the rest of the SOPC system would be handled automatically.

Of course in that case you need to learn how to make SOPC components. You can start by reading that page (http://www.altera.com/support/software/system/sopc/sof-sopc-development-flow.html), and the linked documentation.