[U-Boot] [U-Boot, v2, 2/3] mtd: nand: omap: add support for BCH16_ECC - NAND driver updates

Scott Wood scottwood at freescale.com
Wed Nov 20 00:50:06 CET 2013


On Tue, 2013-11-19 at 13:21 +0000, Gupta, Pekon wrote:
> > From: Scott Wood [mailto:scottwood at freescale.com]
> > > On Tue, Sep 10, 2013 at 12:55:07PM +0530, pekon gupta wrote:
> > > With increase in NAND flash densities occurence of bit-flips has increased.
> > > Thus stronger ECC schemes are required for detecting and correcting
> > multiple
> > > simultaneous bit-flips in same NAND page. But stronger ECC schemes have
> > large
> > > ECC syndrome which require more space in OOB/Spare.
> > > This patch add support for BCH16_ECC:
> > > (a) BCH16_ECC can correct 16 bit-flips per 512Bytes of data.
> > > (b) BCH16_ECC generates 26-bytes of ECC syndrome / 512B.
> > >
> > > Due to (b) this scheme can only be used with NAND devices which have
> > enough
> > > OOB to satisfy following equation:
> > > OOBsize per page >= 26 * (page-size / 512)
> > >
> > > Signed-off-by: Pekon Gupta <pekon at ti.com>
> > >
> > > ---
> > > arch/arm/include/asm/arch-am33xx/cpu.h       | 15 ++++-
> > >  arch/arm/include/asm/arch-am33xx/omap_gpmc.h |  4 +-
> > >  drivers/mtd/nand/omap_gpmc.c                 | 87
> > +++++++++++++++++++++++-----
> > >  include/mtd/mtd-abi.h                        |  3 +-
> > >  4 files changed, 90 insertions(+), 19 deletions(-)
> > 
> > This doesn't apply cleanly.
> > 
> This one is on top of previous patch series like..
> [Part 1] http://lists.denx.de/pipermail/u-boot/2013-November/167393.html
> [Part 2] http://lists.denx.de/pipermail/u-boot/2013-November/167445.html
> 
> So once the above series are cleaned and accepted. I'll rebase and re-send this
> series for BCH16 ecc-scheme again..

Please be sure to mention such dependencies in the future.

-Scott





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