Re: mtd: rawnand: atmel: ECC error after update to kernel 6.6

[Ada Couprie Diaz]

On 01/07/2025 19:04, Zixun LI wrote:

> On Tue, Jul 1, 2025 at 5:49 PM Ada Couprie Diaz <ada.coupriediaz@xxxxxxx> wrote:
> > Hi,
> >
> > I've written a small patch below that I think should fix the issue, but again
> > I don't know if that's upstreamable as-is.
> >
> > > Best regards,
> > > Zixun LI
> > >
> > > [1] https://github.com/torvalds/linux/blob/19583ca584d6f574384e17fe7613dfaeadcdc4a6/drivers/mtd/nand/atmel_nand.c#L1058
> > > [2] https://github.com/torvalds/linux/blob/ffc253263a1375a65fa6c9f62a893e9767fbebfa/drivers/mtd/nand/raw/atmel/pmecc.c#L772
> > Hopefully that can help !
> > Best regards,
> > Ada
> Hi Ada,
> Thank you for looking into this. Internally I've written the same patch as
> yours and it works fine.

Glad to know that you already have a working solution and that I wasn't too far off !
I got interested and wanted to dig into it, I hope it didn't come off wrong.

> What's more interesting is the issue happens depending on chip individual
> difference or aging. Among 3 chips tested, two with date code of 1933 and
> one with 2223. The 1st one has many ECC errors as in the mail, 2nd one
> has less errors, while the 3rd one passed the nandtest without error.
> Maybe that's why this issue is overlooked.

Really interesting behaviour, that could indeed explain how it might 
have been missed during the original refactor as it seems it was tested 
with similar SoCs.

> Best regards,
> Zixun LI
Best regards,
Ada