Nand flash on chip select 7 of the gpmc

Hi all,

           I 'm trying to get the device id and manufacture id of the nand flash, which is connected to chip select 7 of the gpmc.

Trying from the u-boot source code, but values i got are '0'.

I did correct configuration of the gpmc registers.

Pin muxing of the chip select 7 also correct.

So what else i need to check, to access the nand flash.

Thanks in advance,

santosh vastrad