Re: [PATCH 3/3] MTD: spi-nor: add flag to not use sector erase.

From: Marek Vasut
Date: Thu Apr 30 2015 - 19:13:59 EST


On Thursday, April 30, 2015 at 11:13:12 PM, Michal Suchanek wrote:
> The sector size of the flash memory is unclear from datasheet or may
> possibly vary between chips so add a flag to always use 4k blocks.
>
> Currently 4k blocks are always used when possible but in the future
> somebody might want to do some optimizations with sector erase.
>
> Signed-off-by: Michal Suchanek <hramrach@xxxxxxxxx>

I _think_ you might be able to determine the size, no ?

One way is to ask the vendor, but you can also try something like:
1) erase the whole SPI NOR
2) overwrite it with zeroes (or ones ? I think it should be all ones after
erasing).
3) Erase sector 0
4) Read some 128 KiB back
5) Observe what is the difference.

Best regards,
Marek Vasut
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