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Message-ID: <2b859cff-2403-0526-f3ae-749920b3fd8b@linux.intel.com>
Date:   Mon, 23 May 2022 20:18:32 +0800
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Subject: Re: [PATCH 1/2] mtd: spi-nor: macronix: Add support for mx66l2g45g
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To:     Michael Walle <michael@walle.cc>
Cc:     linux-mtd@lists.infradead.org,
        Tudor Ambarus <tudor.ambarus@microchip.com>,
        Pratyush Yadav <p.yadav@ti.com>, linux-kernel@vger.kernel.org
References: <20220522054802.1719443-1-jiaqing.zhao@linux.intel.com>
 <04c432289041752d113c15245361ade8@walle.cc>
 <b3e85d41-9415-b911-6f61-941885af1955@linux.intel.com>
 <fac4b7877f600a4067534fca672dc842@walle.cc>
 <2bf3394e-0a78-c760-16ce-936c12b66b93@linux.intel.com>
 <24cf182693a522ed1f7afd61c7c37029@walle.cc>
From:   Jiaqing Zhao <jiaqing.zhao@linux.intel.com>
In-Reply-To: <24cf182693a522ed1f7afd61c7c37029@walle.cc>
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Okay I've found this was a driver issue. After switching to the new aspeed
spi-mem driver[1], the sysfs interface works.

# xxd -p /sys/bus/spi/devices/spi0.0/spi-nor/sfdp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# md5sum /sys/bus/spi/devices/spi0.0/spi-nor/sfdp
bc3c1443db0c6359432c3cccb6f97943  /sys/bus/spi/devices/spi0.0/spi-nor/sfdp
# cat /sys/bus/spi/devices/spi0.0/spi-nor/jedec_id
c2201c
# cat /sys/bus/spi/devices/spi0.0/spi-nor/partname
mx66l2g45g
# cat /sys/bus/spi/devices/spi0.0/spi-nor/manufacturer
macronix

Since I'm using kernel 5.15, I copied the /drivers/mtd/spi-nor from 5.18-rc7
(I know this it not a clean way, but it works), and applied the SNOR_ID3()
patch. Verified using SNOR_ID3() macro works with this mx66l2g45g and the
values dumped from sysfs are the same.

[    1.696350] spi spi0.0: setup: ignoring unsupported mode bits 200
[    1.703786] spi-nor spi0.0: mx66l2g45g (262144 Kbytes)
[    1.764440] spi-aspeed-smc 1e620000.spi: CE0 read buswidth:2 [0x203c0641]

Due to the lockdown in Shanghai, I am unable to test my 2nd patch at this
time, please temporarily ignore it.

I will perform more tests and update the patch later.

[1] https://lore.kernel.org/linux-mtd/a17b2446-f5a6-d606-8ef4-3931b8bc94da@kaod.org/

Thanks,
Jiaqing

On 2022-05-23 19:59, Michael Walle wrote:
> Hi,
> 
> Am 2022-05-23 12:12, schrieb Jiaqing Zhao:
>>> Am 2022-05-23 10:50, schrieb Jiaqing Zhao:
>>>> Yes this one supports SFDP according to its spec.
>>>>
>>>> On my setup, I cannot see the sysfs object. Do I need to enable some specific
>>>> kernel config or it's SPI controller related? My setup is running kernel 5.15.
>>>
>>> No, it should be there since v5.14. See commit 36ac02286265. And you shouldn't
>>> need to enable any special configuration option.
>>>
>>> Did you do a "find /sys -name sfdp"?
>>>
>>> -michael
>>
>> I tried, it give empty result. The system I'm working on disables kernel module,
>> and the SPI controller driver calls spi_nor_probe() directly, will this be the
>> issue?
>>
>> And is it possible to manually load the spi-nor driver via the bind interface?
>> If it is possible, what should the parameters be?
> 
> Is your spi flash probed at all?
> 
> -michael