Sample Linux driver for Gpmc to connect Xilinx Fpga

Dear All ,
I am working on the GPMC interface for the first time and the task assigned is to have Linux Device Driver

a) Can any one please point to any sample code to configure the Gpmc interface ( mostly we are planning to make simple read & write opration . there is no throughput or interface width 8/16 bit. limitation) It is supposed to do bare minimum read / write on fpga

b) As an starting point i am got a sample NAND DRIVER for GPMC— just started going through it.

Sorry if i am missing any simple starting understanding

Thank You ,
Ashish