... and then tell us what it is, and provide a link to the datasheet. Not all NAND flash devices are identical. Of course, YOU can read the datasheet, too. That will tell you what you need to know.

If your question is more general, i.e. "how can I create the addresses necessary to address a 2GB memory?" then that's a different subject. Between the datasheet for the AT89C5131 and datasheet for your chosen NAND flash memory, the information is available. Keep in mind, though, that generating 31 addresses and keeping track of them, won't be trivial, and, even less so, it won't be convenient. It's absolutely possible, though.

RE