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Date:   Tue, 28 Nov 2023 09:47:22 +0000
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Subject: Re: [PATCH] mtd: spi-nor: stop printing superfluous debug info
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From:   Tudor Ambarus <tudor.ambarus@linaro.org>
To:     liao jaime <jaimeliao.tw@gmail.com>,
        Michael Walle <michael@walle.cc>
Cc:     Miquel Raynal <miquel.raynal@bootlin.com>, jaimeliao@mxic.com.tw,
        pratyush@kernel.org, richard@nod.at, linux-mtd@lists.infradead.org,
        linux-kernel@vger.kernel.org
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On 11/28/23 09:39, Tudor Ambarus wrote:
> 
> cut
> 
>>>> Maybe we don't need this at all, as long as one message remains about
>>>> the JEDEC ID, but keep in mind that spi-nors are commonly storing the
>>>> rootfs and if your spi-nor does not boot you don't have a userspace yet
>>>> and all the debugfs entries are purely useless.
>>>
>>> Good point.
>>>
>>> Just curious, do you know any boards which has the rootfs writable on
>>> the spi-nor flash?
>> I am also interested.
>>
> 
> Having the rootfs stored on SPI NOR is a poor design decision as you're
> better of with a NAND, which is cheaper and faster on writes. I tried in
> the past a ubifs on top of a large (64 and 128MB) SPI NOR flash. But
> they were plug-able flashes, not something that is always tied to the
> board. Microchip's sama7g5ek comes with a 128MB macronix SPI NOR flash
> populated. But there are other vendors that provide large SPI NORs if
> really needed.
> 

pressed sent too soon :). What I wanted to say is that it's not uncommon
for vendors to populate large SPI NOR flashes, there are others as well,
thus Miquel's concerns are valid. There may be people out there having
rootfs on top of SPI NORs.

Cheers,
ta