Re: [PATCH v11 07/10] mtd: spi-nor: Add stacked memories support in spi-nor

Tudor Ambarus
2023-12-15T10:33:05Z

On 12/15/23 10:02, Mahapatra, Amit Kumar wrote:
> Hello Tudor,

Hi,

>
>> -----Original Message-----
>> From: Tudor Ambarus <tudor.ambarus@linaro.org>
>> Sent: Friday, December 15, 2023 1:40 PM
>> To: Mahapatra, Amit Kumar <amit.kumar-mahapatra@amd.com>;
>> broonie@kernel.org; pratyush@kernel.org; miquel.raynal@bootlin.com;
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>> Cc: linux-spi@vger.kernel.org; linux-kernel@vger.kernel.org;
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>> Subject: Re: [PATCH v11 07/10] mtd: spi-nor: Add stacked memories support
>> in spi-nor
>>
>>
>>
>> On 15.12.2023 09:55, Mahapatra, Amit Kumar wrote:
>>>> Thanks! Can you share with us what flashes you used for testing in
>>>> the stacked and parallel configurations?
>>> I used SPI-NOR QSPI flashes for testing stacked and parallel.
>>
>> I got that, I wanted the flash name or device ID.
>
> N25Q00A, MX66U2G45G, IS25LP01G & W25H02JV are some of the QSPI flashes on
> which we tested. Additionally, we conducted tests on over 30 different
> QSPI flashes from four distinct vendors (Miron, Winbond, Macronix, and ISSI).
>

Great.

>> What I'm interested is if each flash is in its own package. Are they?
>
> I'm sorry, but I don't quite understand what you mean by "if each flash in
> its own package."
>

There are flashes that are stacked at the physical level. It's a single
flash with multiple dies, that are all under a single physical package.

As I understand, your stacked flash model is at logical level. You have
2 flashes each in its own package. 2 different entities. Is my
understanding correct?

Cheers,
ta