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Date:   Thu, 8 Apr 2021 17:49:22 +0200
From:   Miquel Raynal <miquel.raynal@bootlin.com>
To:     Daniel Palmer <daniel@0x0f.com>
Cc:     linux-mtd@lists.infradead.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2] mtd: spinand: add support for Foresee FS35ND01G-S1Y2
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Hi Daniel,

Daniel Palmer <daniel@0x0f.com> wrote on Wed, 7 Apr 2021 21:01:01 +0900:

> Hi Miquel,
> 
> On Wed, 7 Apr 2021 at 17:02, Miquel Raynal <miquel.raynal@bootlin.com> wrote:
> > You may look at micron_8_ecc_get_status() helper to guide you. But
> > IMHO, if there are 0-3 bf, you should probably assume there were 3 bf
> > and return 3, if there were 4, return 4, if it's uncorrectable return
> > -EBADMSG otherwise -EINVAL.  
> 
> Understood.
> 
> > We should verify that this does not mess with UBI wear leveling
> > though. Please check that returning 3-bit errors no matter the
> > actual number of flipped bits does not lead UBI to move the data away
> > (I think it's fine but we need to be sure otherwise the implementation
> > proposal is not valid).  
> 
> Ok. I'm not sure how to check that yet but I'll look into it.
> 

You can probably check the threshold in sysfs
(/sys/class/mtd/mtdX/*threshold*).

Thanks,
Miquèl