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From:   Tom Fitzhenry <tom@tom-fitzhenry.me.uk>
Subject: Re: [PATCH v2] mtd: spi-nor: siliconkaiser: add support for sk25lp128
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On 21/7/22 18:08, Tudor.Ambarus@microchip.com wrote:
> Does this flash implement the manufacturer ID continuation codes?
> Can you read more bytes of manufacturer ID and dump them?

I'm not sure how to do this, but from what I can gather, flash chips 
that implement manufacturer ID continuation codes return >3 bytes in 
response to RDID. Is this correct?

To do this, in tools/spi/spidex_fdx.c I set buf[0] = 0x9F, and then 
executed this with a large recvbuf:

$ sudo ./a.out -m 6 /dev/spidev0.0
/dev/spidev0.0: spi mode 0x0, 8 bits per word, 10000000 Hz max
response( 6,  7):  25 70 18 25 70 18

It looks like the 3-byte response has cycled, suggesting this flash chip 
does not implement continuation codes.

> If the flash does not define the continuation codes, we'll need to
> add this flash in a ID collisions driver.

I will do this in v3.