Message-ID: <46f438c2-6f5f-645e-23b4-95216ec23ca3@nokia.com>
Date:   Tue, 23 Nov 2021 13:40:44 +0100
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Subject: Re: [PATCH] mtd: spi-nor: mt25qu: Ignore 6th ID byte
Content-Language: en-US
To:     Michael Walle <michael@walle.cc>
Cc:     linux-mtd@lists.infradead.org,
        Tudor Ambarus <tudor.ambarus@microchip.com>,
        Pratyush Yadav <p.yadav@ti.com>,
        Miquel Raynal <miquel.raynal@bootlin.com>,
        Richard Weinberger <richard@nod.at>,
        Vignesh Raghavendra <vigneshr@ti.com>,
        linux-kernel@vger.kernel.org
References: <20211119080402.20262-1-alexander.sverdlin@nokia.com>
 <9a158e2ef6635212c1e353590e3b773b@walle.cc>
 <1e133bc6-5edb-c4ce-ad44-3de77048acf2@nokia.com>
 <e9589af968d7b9dafbce17325dbf8472@walle.cc>
 <2bf37a35-1ccf-f4fa-c999-42b9154a2914@nokia.com>
 <88db136a146edf53801d86509b52d40f@walle.cc>
From:   Alexander Sverdlin <alexander.sverdlin@nokia.com>
In-Reply-To: <88db136a146edf53801d86509b52d40f@walle.cc>
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Hi!

On 23/11/2021 09:14, Michael Walle wrote:
>>
>> Some people ask themselves why this table keeps growing if there is SFDP...
>> I see the point in fixups, but maybe at some point we will be able to support
>> some devices just out of the box?
> 
> Are these features detectable by SFDP? Without knowing anything, as you ignored
> my former question, I'd say no.

Well, I just had nothing to say on your question.
It wasn't my intention to study security features of a chip, which I don't use.
There is a background which I didn't tell you, which might even emphasize the
importance of security version support even without security features:
Micron might want to "streamline" the product palette and as security version
is backwards compatible (except 6th byte, which is not an ID, actually), a
buyer can get security version instead of normal one.

And the reason for the above is, mainly, because there are real problems with
this chip, even without new features, sector erase doesn't work properly
(refer to my other email in this thread).

-- 
Best regards,
Alexander Sverdlin.