ECC Errors/Sub-page Read Failures

[Peter LaDow]

On Fri, Feb 28, 2014 at 7:27 PM, Peter LaDow <petela at gocougs.wsu.edu> wrote:
> We have been using a Samsung NAND part for several years (Samsung
> K9WAG08U1D) without any problems.  We transitioned from 2.6 to the 3.0
> kernel with a few tweaks to our NAND driver without any hiccups.  (Or
> NAND controller is a custom part implemented in an FPGA with our own
> NAND driver in the kernel).
>
> However, Samsung has announced the end of life for the part.  However,
> they have a revision (K9WAG08U1E) they claim is a drop-in replacement.
>  But so far we are having trouble qualifying the part because of ECC
> errors.  We made no changes to our kernel, driver, or NAND controller.
>  The only change is the physical part.

For those that are interested, we tracked down the issue.  The die rev
changed the number of partial programs per page from 4 to 1.  Hence
the additional sub-page writes corrupted the data.

Pete