[RFC] extending nand_ecclayout.eccpos once again

[Jamie Lokier]

Harald Welte wrote:
> Creating raw images?  I'm also not sure how often that is being
> done.  Why would you precompute an image with ECC and then write
> that to NAND rather than having the NAND layer generate the ECC
> while writing the image (like writing any other data)?

One reason is to be resistant to errors (such as RAM bit-flips) which
occur in flight from the time the data was read or generated (perhaps
a long time ago or far away), until it is written.

Such errors do happen, but it's a bit premature to start coding it in
MTD, as it would be far more valuable to have it in ordinary
filesystems and copying tools, and that looks quite a long way off :-)

-- Jamie