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Date: Tue, 15 May 2018 15:49:45 +0200
From: Boris Brezillon <boris.brezillon@bootlin.com>
To: Cardoen Pieter <P.Cardoen@TELEVIC.com>
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Subject: Re: GPMI nand flash ECC errors with mainline kernel
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On Tue, 15 May 2018 11:46:32 +0000
Cardoen Pieter <P.Cardoen@TELEVIC.com> wrote:

> Dear
> 
> I am currently trying to use the mainline kernel on a custom imx6ul board with an SLC NAND flash device (29F4G08ABADAH4). When the rootfs is mounted, I get continuously ECC errors (see log below).
> 
> I am however sure that the rootfs is programmed. The device boots with an older kernel version on the same device.

Which version works? Is this a vendor tree or a mainline kernel? Looks
like the version that fails is 4.15. Are you sure the ECC config is
exactly the same between the old and new kernel?

> 
> I also noticed that with my previous kernel version, it used mtd->_read in function mtd_read while now it is using mtd->_read_oob.

It's unlikely to be the root cause for these ECC failures.