Re: [PATCH 3/3] mtd: spi-nor: issi: is25wp256: Enable Quad Input Page Program

[Sudip Mukherjee]

Hi Michael,

On Mon, Jul 18, 2022 at 8:39 AM Michael Walle <michael@xxxxxxxx> wrote:
>
> Am 2022-07-12 18:38, schrieb Sudip Mukherjee:
> > The flash chip is25wp256 supports Quad Input Page Program. Enable it
> > in its no_sfdp_flags flags.
>
> Are you sure, that chip doesn't have SFDP? Even the oldest datasheet
> I've found [1] mention SFDP.

Yes, that is what I expected from the datasheet. But from the driver code,
spi_nor_init_params() is calling spi_nor_init_params_deprecated() as
'parse_sfdp' is not true.
and looking at issi_nor_parts[], I can see is25wp256 is not marked
with 'PARSE_SFDP' so it
will skip parsing SFDP. The same datasheet also has is25lp256 which is
marked with 'PARSE_SFDP'
in the driver.
I tried to add 'PARSE_SFDP' to is25wp256, and I can see its mostly
working but its not using
Quad Input Page Program. I guess this support was not discovered from SFDP.


--
Regards
Sudip