[RFC] adding support for OneNAND flash memory

[kyungmin park]

[snip]
> May be it makes sense to put it to drivers/mtd/nand/onenand if some
> parts of the existing code (like BBT, etc) may be reused? Possibly,
> you'll need to split the existing code on what is NAND-specific and what
> is OK for both OneNAND and NAND.
> 
> => As I said before, it's difficult to modify/extend current nand
directory
> to support OneNAND. That's why I suggested to add onenand directory.

> It's not hard to extend. Just add onenand.c to it, if thats all what is
> needed. The question is whether the bad block table code can be shared
> or not. I agree that nand_base.c can not be tweaked for OneNAND.

Although OneNAND uses NAND core internally, the interface is very different
from NAND. The viewpoint of the hardware it seems to be connected with NOR.
Also OneNAND supports synchronous burst read as NOR does
I wonder the different interface of flash putting together is accptable?

Currently, I don't apply bad block table code to onenand. But I think
there's no problem to use current bbt code.