Re: [PATCH 2/2] mtd: spi-nand: macronix: Add randomizer support

[Cheng Ming Lin]

Hi Miquel,

Miquel Raynal <miquel.raynal@xxxxxxxxxxx> 於 2025年8月8日 週五 下午6:19寫道：
>
> On 08/08/2025 at 17:55:03 +08, Cheng Ming Lin <linchengming884@xxxxxxxxx> wrote:
>
> > From: Cheng Ming Lin <chengminglin@xxxxxxxxxxx>
> >
> > Enable randomizer function by specific flowchart to set the default value
> > of RANDEN to 1.
> >
> > Randomizer introduces two new DT properties for child nodes to configure
> > the randomizer functionality and coverage options.
> >  - mxic,enable-randomizer-otp: Specify whether to activate the randomizer
> >                                feature.
> >  - mxic,randopt: Define the randomizer area per page.
>
> Can we create a global NAND DT property for that? Enabling a randomizer
> is quite a generic step.
>
> > The penalty of randomizer are subpage accesses prohibited and more time
> > period is needed in program operation and entering deep power-down mode.
> > i.e., tPROG 320us to 360us (randomizer enabled).
>
> Do you want to share what is the added value in terms of lifetime to
> enable the randomizer, given the drawbacks which are significant?

The randomizer mainly targets extremely unbalanced data patterns,
which might potentially lead to data errors.

Please refer to the attached document:
https://www.mxic.com.tw/Lists/ApplicationNote/Attachments/2151/AN1051V1-The%20Introduction%20of%20Randomizer%20Feature%20on%20MX30xFxG28AD_MX35xFxG24AD.pdf

Figure 1 shows that continuously programming too
many 0s can result in data errors.

>
> Thanks,
> Miquèl

Thanks,
Cheng Ming Lin