Re: [PATCH v4] mtd: nand: pass page number to ecc->write_xxx() methods

From: Brian Norris
Date: Tue Oct 13 2015 - 14:06:23 EST


On Tue, Oct 13, 2015 at 11:22:18AM +0200, Boris Brezillon wrote:
> The ->read_xxx() methods are all passed the page number the NAND controller
> is supposed to read, but ->write_xxx() do not have such a parameter.
>
> This is a problem if we want to properly implement data
> scrambling/randomization in order to mitigate MLC sensibility to repeated
> pattern: to prevent bitflips in adjacent pages in the same block we need
> to avoid repeating the same pattern at the same offset in those pages,
> hence the randomizer/scrambler engine need to be passed the page value
> in order to adapt its seed accordingly.
>
> Moreover, adding the page parameter to the ->write_xxx() methods add some
> consistency to the current API.
>
> Signed-off-by: Boris Brezillon <boris.brezillon@xxxxxxxxxxxxxxxxxx>
> CC: Josh Wu <josh.wu@xxxxxxxxx>
> CC: Ezequiel Garcia <ezequiel.garcia@xxxxxxxxxxxxxxxxxx>
> CC: Maxime Ripard <maxime.ripard@xxxxxxxxxxxxxxxxxx>
> CC: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
> CC: Huang Shijie <shijie.huang@xxxxxxx>
> CC: Stefan Agner <stefan@xxxxxxxx>
> CC: devel@xxxxxxxxxxxxxxxxxxxx
> CC: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> CC: linux-kernel@xxxxxxxxxxxxxxx
> ---
> Changes since v3:
> - rebased on l2-mtd/master
>
> Changes since v2:
> - fixed compilation error in the gpmi driver
> - compile tested all impacted drivers except the bf5xx_nand,
> fsl_elbc_nand and fsl_ifc_nand ones
>
> Changes since v1:
> - rebased on l2-mtd/master
> - fixed compilation error in the docg4 driver

Applied to l2-mtd.git
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