[PATCH v2 2/6] mtd: spi-nor: add erase die (chip) capability

[Fabio Estevam]

On 03/11/2023 11:37, Tudor Ambarus wrote:

> I confirm I see the same behavior on n25q00 flash.
> Erased 134217728 bytes from address 0x00000000 in flash
> 
> real	3m49.082s
> user	0m0.000s
> sys	3m48.485s
> 
> I'll continue to investigate this at a best effort rate, expect for 
> some
> delays, I'm handling SPI NOR mostly in my spare time. Happy to guide 
> you
> though. You may join #mtd irc channel for short questions, see where it
> is in the MAINTAINERS file.

Thanks, Tudor.

Reading the datasheet at:
https://www.micron.com/-/media/client/global/documents/products/data-sheet/nor-flash/serial-nor/mt25q/die-rev-b/mt25q_qlkt_u_01g_bbb_0.pdf

The last entry of Table 49 shows:

512Mb bulk erase time: Typ: 153 s Max: 460 s

512Mb corresponds to the size of one die.

mt25qu01g has two dies so the bulk erase time would be from 306 to 920 s 
(5 to 15 minutes!)

It seems that there is not much we can do about this long erase time.

Is my understanding correct?