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

[Boris Brezillon <boris.brezillon@free-electrons.com>]

On Thu, 1 Oct 2015 10:17:50 -0700
Brian Norris <computersforpeace@gmail.com> wrote:

> On Mon, Aug 24, 2015 at 07:10:19PM +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 the ->write_xxx() methods add some
> > consistency to the current model.
> > 
> > Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
> > CC: Josh Wu <josh.wu@atmel.com>
> > CC: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
> > CC: Maxime Ripard <maxime.ripard@free-electrons.com>
> > CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> > CC: Huang Shijie <shijie.huang@intel.com>
> > CC: Bryan Wu <bryan.wu@analog.com>
> > CC: devel@driverdev.osuosl.org
> > CC: linux-arm-kernel@lists.infradead.org
> > CC: linux-kernel@vger.kernel.org
> > 
> > ---
> >  drivers/mtd/nand/atmel_nand.c                 |  6 ++++--
> >  drivers/mtd/nand/bf5xx_nand.c                 |  3 ++-
> >  drivers/mtd/nand/brcmnand/brcmnand.c          |  4 ++--
> >  drivers/mtd/nand/cafe_nand.c                  |  3 ++-
> >  drivers/mtd/nand/denali.c                     |  5 +++--
> >  drivers/mtd/nand/docg4.c                      |  4 ++--
> >  drivers/mtd/nand/fsl_elbc_nand.c              |  4 ++--
> >  drivers/mtd/nand/fsl_ifc_nand.c               |  2 +-
> >  drivers/mtd/nand/gpmi-nand/gpmi-nand.c        |  6 +++---
> >  drivers/mtd/nand/hisi504_nand.c               |  3 ++-
> >  drivers/mtd/nand/lpc32xx_mlc.c                |  3 ++-
> >  drivers/mtd/nand/lpc32xx_slc.c                |  5 +++--
> >  drivers/mtd/nand/nand_base.c                  | 31 ++++++++++++++++++---------
> >  drivers/mtd/nand/omap2.c                      |  3 ++-
> >  drivers/mtd/nand/pxa3xx_nand.c                |  3 ++-
> >  drivers/mtd/nand/sh_flctl.c                   |  3 ++-
> >  drivers/mtd/nand/sunxi_nand.c                 |  5 +++--
> >  drivers/staging/mt29f_spinand/mt29f_spinand.c |  3 ++-
> >  include/linux/mtd/nand.h                      |  6 +++---
> >  19 files changed, 63 insertions(+), 39 deletions(-)
> 
> Tip for rebasing -- I noticed one build failure for docg4:
> 
>   drivers/mtd/nand/docg4.c: In function ‘docg4_block_markbad’:
>   drivers/mtd/nand/docg4.c:1116:2: error: too few arguments to function ‘docg4_write_page’
>   drivers/mtd/nand/docg4.c:985:12: note: declared here

Fixed in v2, thanks for the pointer.



-- 
Boris Brezillon, Free Electrons
Embedded Linux and Kernel engineering
http://free-electrons.com