mtd support for large NAND

[Charles Manning]

On Friday 12 October 2007 21:36:09 falls huang wrote:
> Hello !
>
>   How can I simulate a large nandflash(>4G) in linux PC ? I want to
> take a look at it, but I don't have any develop-board that has 4G

There are a few problems you face here. Firstly, mtd does not support >4G 
which will need fixing.

Secondly, even if your system has > 4G it might not be all simultaneously 
accessible and you will need to use highmem as a way to do temporary mappings 
to access this memory.

I might be tempted to try do this using some sort of userspace driver then 
just backing the driver with regular files (eg. 8x1G files to simulate 8G of 
NAND).


>
> On 10/11/07, Artem Bityutskiy <dedekind at infradead.org> wrote:
> > On Thu, 2007-10-11 at 09:11 +1300, Charles Manning wrote:
> > > Last I looked (2.6.23), mtd_info is limited by a u32 size field to
> > > 4Gbytes of flash. That's no longer very large and is limiting some
> > > applications.
> > >
> > > Is anyone working on this?
> >
> > Yeah, the problem is known, but nobody is working on the fix AFAIK.
> >
> > --
> > Best regards,
> > Artem Bityutskiy (Битюцкий Артём)
> >
> >
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