[Yaffs] Re: YAFFS fs images not working the way I expect

[Thomas Gleixner]

On Fri, 2004-10-22 at 11:35 -0700, David Wuertele wrote:
> Thomas> OOB info is part of the filesystem.
> 
> If it is, the designer made a boo-boo!  It isn't called "out-of-band"
> for nothing!

Yeah, I'm too stupid to understand how NAND works and you're the expert.
Design your own filesystem, if you know to do it better.

_ALL_ NAND aware filesystems, I'm aware of, use the OOB. And for the new
2K chips + Hardware ECC it is even neccecary to move parts of the fs
into the OOb layer.

> Thomas> ECC is part of error correction in the NAND layer. How should
> Thomas> this work without?
> 
> 1.  ECC is optional in the NAND layer

That's utter crap. It is not recommended to use NAND without ECC for a
good reason

> 2.  ECC should be a component of the NAND driver, not of the
>     filesystem.

It is part of the NAND driver, but dd and your programmer are not aware
of that. Think about that for a second

> Thomas> nandwrite from MTD/utils programs images with OOB info, ECC
> Thomas> and is bad block aware.
> 
> But I need to pre-load my flash with a programmer.  This is for the
> purposes of mass production, and there's no way to do it on a machine
> already running linux.  How am I going to get my YAFFS partition onto
> the flash?

Oh, your programmer does not support this. There are programmers
available, which handle NAND including OOB programming. 

tglx