[U-Boot] [PATCH] Add MTD core & partition

[Michael Lawnick]

Stefan Roese <sr <at> denx.de> writes:

> 
> On Friday 19 September 2008, Michael Lawnick wrote:
> > > BTW: Which NOR FLASH driver are you using? The common CFI driver? It has
> > > no real connection to the MTD layer which is needed for the UBI port from
> > > Kyungmin. Did you think about this?
> >
> > We are using CFI driver for AM29GL512.
> > As said we are _planning_ to integrate, i.e. I'm currently gathering
> > information. We need r/o access from u-boot to find our kernel and boot it.
> > Writing to flash could be done from Linux.
> 
> Understood.
> 
> > What are the problems to face?
> 
> As I mentioned the CFI driver is missing the interface to the MTD layer. This 
> is available for NAND and OneNAND but missing for NOR in the U-Boot CFI 
> implementation. It really is not needed right now and such an extension has 
> to be made carefully since it adds new code which increases the image size of 
> all boards using this driver. The only option (I can think of) to not 
> increase the image size for those boards would be to add this MTD connection 
> via #ifdef's. But this will not help to make the code more readable. 
> 
Hmm, seems I've got some problems to understand.
If there is a clearly defined API (which I haven't found yet) it should be
independent from H/W (NAND/NOR/SRAM/...) IMHO. If not, UBI will be NAND-only :-( 
Could you give me a kick into the right direction, so I will find e.g. a .h file
where the functions are listed that have to be supported by H/W-layer driver?

#ifdef's could be avoided by using a different sort of driver for the same H/W,
e.g. cfi_flash and cfi_ubi_flash.

Kind regards,
Michael