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Date: Fri, 15 Dec 2023 10:09:40 +0200
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Subject: Re: [PATCH v11 07/10] mtd: spi-nor: Add stacked memories support in
 spi-nor
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To: "Mahapatra, Amit Kumar" <amit.kumar-mahapatra@amd.com>,
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From: Tudor Ambarus <tudor.ambarus@linaro.org>
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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.

What I'm interested is if each flash is in its own package. Are they?

> 
>>>> can combine a SPI NOR with a SPI NAND in stacked configuration?
>>> No, Xilinx/AMD QSPI controllers doesn't support this configuration.
>>>
>> 2 SPI NANDs shall work with the AMD controller, right?
> We never tested 2 SPI-NAND with AMD controller.

I was asking because I think the stacked layer shall be SPI MEM generic,
and not particular to SPI NOR.

>> I skimmed over the QSPI controller datasheet and wondered why one would
>> get complicated with 2 Quad Flashes when we have Octal. But then I saw that
>> the same SoC can configure an Octal controller (the Octal and Quad
>> controllers seems mutual exclusive) and that the Octal one can operate 2
>> octal flashes in stacked mode ????.
> Thats correct .
> 
> Please let me know how you want me to proceed on this.

I got you. Still need to allocate more time on this.

Cheers,
ta