[RFC 09/10] mtd: spi-nor: Disable hybrid mode for SPANSION S25FS-S family

[Prabhakar Kushwaha]

> -----Original Message-----
> From: Cyrille Pitchen [mailto:cyrille.pitchen at wedev4u.fr]
> Sent: Wednesday, December 06, 2017 4:28 PM
> To: Prabhakar Kushwaha <prabhakar.kushwaha at nxp.com>; linux-
> mtd at lists.infradead.org
> Cc: boris.brezillon at free-electrons.com; computersforpeace at gmail.com; Rajat
> Srivastava <rajat.srivastava at nxp.com>; dedekind1 at gmail.com
> Subject: Re: [RFC 09/10] mtd: spi-nor: Disable hybrid mode for SPANSION S25FS-
> S family
> 
> Hi Prabhakar,
> 
> Le 06/12/2017 à 09:15, Prabhakar Kushwaha a écrit :
> > The S25FS-S family physical sectors may be configured as a hybrid
> > combination of eight 4-kB parameter sectors at the top or bottom
> > of the address space with all but one of the remaining sectors
> > being uniform size.
> > The default status of the flash is the hybrid architecture.
> > The parameter sectors and the uniform sectors have different erase
> > commands.
> >
> > This patch disables the hybrid sector architecture which makes the
> > flash have uniform sector size and uniform erase command.
> >
> 
> This issue should be addressed in a generic way, not Spansion specific,
> by adding support of the optional Sector Map Parameter Table (SFDP).
> In case of non uniform memories, like this Spansion S25FS-S family or
> SST26, the Sector Map Parameter Table becomes mandatory as a SFDP table.
> 
> From the JESD216B specification, about the JEDEC Sector Map Parameter Table:
> """
> This table is required when a memory device:
> * Has sectors of more than one size
> * Or, does not allow all Erase Type commands to be applied to all sectors.
> """
> 

Thanks for the guidance. Let me explore Sector Map Parameter Table (SFDP)

--pk.