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Message-ID: <125fe1a7-bc52-46a7-93d5-b09caf5ca9f8@linaro.org>
Date:   Tue, 26 Sep 2023 14:18:55 +0100
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Subject: Re: [PATCH] mtd: spi-nor: atmel: add at25ff321a entry
To:     Nicolas Ferre <nicolas.ferre@microchip.com>,
        miquel.raynal@bootlin.com, linux-mtd@lists.infradead.org
Cc:     linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org
References: <20230908151400.164470-1-nicolas.ferre@microchip.com>
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 <4c9b0dff-6350-376b-60ac-c36f98378a51@microchip.com>
 <306a6aa0-c608-418a-a591-6f8aa95817fb@linaro.org>
 <925723a2-dc2d-9949-5b8f-4351b49d2f4b@microchip.com>
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From:   Tudor Ambarus <tudor.ambarus@linaro.org>
In-Reply-To: <925723a2-dc2d-9949-5b8f-4351b49d2f4b@microchip.com>
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On 9/26/23 13:59, Nicolas Ferre wrote:
> On 21/09/2023 at 09:14, Tudor Ambarus wrote:
>> EXTERNAL EMAIL: Do not click links or open attachments unless you know
>> the content is safe
>>
>> On 9/20/23 17:16, Nicolas Ferre wrote:
>>> On 19/09/2023 at 18:12, Tudor Ambarus wrote:
>>>> On 08.09.2023 18:14, nicolas.ferre@microchip.com wrote:
>>>>> From: Nicolas Ferre <nicolas.ferre@microchip.com>
>>>>>
>>>>> Add the at25ff321a 4MB SPI flash which is able to provide
>>>>> SFDP informations.
>>>>> Datasheet:
>>>>> https://www.renesas.com/us/en/document/dst/at25ff321a-datasheet
>>>>>
>>>>> Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
>>>>> ---
>>>
>>> [..]
>>>
>>>>>    drivers/mtd/spi-nor/atmel.c | 4 ++++
>>>>>    1 file changed, 4 insertions(+)
>>>>>
>>>>> diff --git a/drivers/mtd/spi-nor/atmel.c b/drivers/mtd/spi-nor/atmel.c
>>>>> index 58968c1e7d2f..c94d52951481 100644
>>>>> --- a/drivers/mtd/spi-nor/atmel.c
>>>>> +++ b/drivers/mtd/spi-nor/atmel.c
>>>>> @@ -184,6 +184,10 @@ static const struct flash_info atmel_nor_parts[]
>>>>> = {
>>>>>                 FLAGS(SPI_NOR_HAS_LOCK | SPI_NOR_SWP_IS_VOLATILE)
>>>>>                 NO_SFDP_FLAGS(SECT_4K)
>>>>>                 .fixups = &atmel_nor_global_protection_fixups },
>>>>> +     { "at25ff321a", INFO(0x1f4708, 0, 64 * 1024,  64)
>>>>> +             FLAGS(SPI_NOR_HAS_LOCK | SPI_NOR_SWP_IS_VOLATILE)
>>>>> +             PARSE_SFDP
>>>>> +             .fixups = &atmel_nor_global_protection_fixups },
>>>>
>>>> We have recently changed how the flash entries are defined. Would you
>>>> please try the following changes instead?
>>>>
>>>> diff --git a/drivers/mtd/spi-nor/atmel.c b/drivers/mtd/spi-nor/atmel.c
>>>> index 95f0e139284e..44218716d81e 100644
>>>> --- a/drivers/mtd/spi-nor/atmel.c
>>>> +++ b/drivers/mtd/spi-nor/atmel.c
>>>> @@ -213,6 +213,12 @@ static const struct flash_info
>>>> atmel_nor_parts[] = {
>>>>                   .flags = SPI_NOR_HAS_LOCK | SPI_NOR_SWP_IS_VOLATILE,
>>>>                   .no_sfdp_flags = SECT_4K,
>>>>                   .fixups = &atmel_nor_global_protection_fixups
>>>> +       }, {
>>>> +               .id = SNOR_ID(0x1f, 0x47, 0x08),
>>>> +               .name = "at25ff321a",
>>>> +               .flags = SPI_NOR_HAS_LOCK | SPI_NOR_SWP_IS_VOLATILE,
>>>
>>> Here, I added:
>>>
>>>                 .no_sfdp_flags = SECT_4K,
>>>
>>> to match the other devices of the family... I checked on the datasheet,
>>> 4K sectors are okay, but I don't know exactly if this is eligible to the
>>> "no_sfdb_flags" property... forgive me, I didn't check further knowing
>>> that you might have better view on this than me ;-)
>>
>> yeah, no worries. You should not specify 4k here, as it should already
>> be set when parsing SFDP. You can use mtdinfo /dev/mtdx to check what
>> erase size gets set. In the core we set the maximum supported erase size
>> for speed considerations and making ubifs happy, so you'll probably see
>> 64k when checking with mtdinfo. But you can try 4k erases as well by
>> setting MTD_SPI_NOR_USE_4K_SECTORS.
> 
> Absolutely, here is what I'm experiencing:
> # no_sfdp_flags not set / linux-next / sama5d27 wlsom1 ek
> # CONFIG_MTD_SPI_NOR_USE_4K_SECTORS=y
> root@sama5d27-wlsom1-ek-sd:~# mtdinfo /dev/mtd0
> mtd0
> Name:                           spi0.1
> Type:                           nor
> Eraseblock size:                4096 bytes, 4.0 KiB
> Amount of eraseblocks:          1024 (4194304 bytes, 4.0 MiB)
> Minimum input/output unit size: 1 byte
> Sub-page size:                  1 byte
> Character device major/minor:   90:0
> Bad blocks are allowed:         false
> Device is writable:             true
> 
> # no_sfdp_flags not set / linux-next / sama5d27 wlsom1 ek
> # # CONFIG_MTD_SPI_NOR_USE_4K_SECTORS is not set
> root@sama5d27-wlsom1-ek-sd:~# mtdinfo /dev/mtd0
> mtd0
> Name:                           spi0.1
> Type:                           nor
> Eraseblock size:                65536 bytes, 64.0 KiB
> Amount of eraseblocks:          64 (4194304 bytes, 4.0 MiB)
> Minimum input/output unit size: 1 byte
> Sub-page size:                  1 byte
> Character device major/minor:   90:0
> Bad blocks are allowed:         false
> Device is writable:             true
> 

looks good!

>>>> +               .fixups = &atmel_nor_global_protection_fixups
>>>> +       }, {
>>>>           }, {
>>>>                   .id = SNOR_ID(0x1f, 0x48, 0x00),
>>>>                   .name = "at25df641",
>>>
>>> That works perfectly well (I can re-post the test results as my previous
>>> patch if needed): do you want me to send the updated patch with your
>>> Suggested-by tag or you can send yours, tell me what you prefer.
>>
>> Send a new patch please, it was just a suggestion to speed the things up.
> 
> Sure, I'm on it ;-)
> 
>>> Thanks for the heads-up on this update that I hadn't noticed. Best
>>> regards,
>>>    Nicolas
>>>
>> you're welcome! Cheers!
> 
> Best regards,
>  Nicolas
>