Re: nand oob layout assumptions

[Thomas Gleixner <tglx@linutronix.de>]

On Sunday 28 March 2004 10:06, Charles Manning wrote:
> I agree with the idea of abstacting this as much as possible. Where the EEC
> is stores (if indeed it even is stored in OOB) should not be the FS's
> concern and should not be known to the FS. The FS should just be told that
> the ECC passed, failed or fixed a single bit error.

No problem with that

> Unless we go for one abstract interface it will [continue to] be hell to
> support more than one FS (it is already a /dev/ass/pain to try get YAFFS
> and JFFS2 going on one machine due to different OOB layouts). The [already
> bad] situation will only get worse when trying to deal with all the fun
> that the newer NAND devices bring us.

He ? I'm running YAFFS and JFFS2 since a long time on the same device and it 
works without any PITA. 

I just want to bring back into memories, that we had a long discussion about 
an abstract interface 2 years ago. There was no way to find a common solution 
as nobody was willing to break either JFFS2 or YAFFS1 or both. 

Again. I agree with the idea of an abstract interface as long as we keep the 
current stuff running. 

> No bitmask. That just passes mucky knowledge through the interface.
>
> Rather:
> * Have the mtd tell the FS the number of unused bytes in the OOB.
> * Pass a byte array through the interface and the mtd packs/unpacks this
> around the ECC, bad block markers and other stuff.

No objections.

-- 
Thomas
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