RE: [PATCH v1 3/5] mtd: atmel_nand: Support PMECC on SAMA5D2

Yang, Wenyou
2016-01-14T01:18:03Z

> -----Original Message-----
> From: Rob Herring [mailto:robh@kernel.org]
> Sent: 2016年1月14日 9:13
> To: Romain Izard <romain.izard.pro@gmail.com>
> Cc: linux-mtd@lists.infradead.org; devicetree@vger.kernel.org; Yang, Wenyou
> <Wenyou.Yang@atmel.com>; Josh Wu <rainyfeeling@outlook.com>; Ferre,
> Nicolas <Nicolas.FERRE@atmel.com>
> Subject: Re: [PATCH v1 3/5] mtd: atmel_nand: Support PMECC on SAMA5D2
>
> On Wed, Jan 13, 2016 at 05:34:15PM +0100, Romain Izard wrote:
> > Starting with the SAMA5D2, there is a new revision of the Atmel PMECC
> > controller that can correct 32 bits in each sector. This controller is
> > not 100% compatible with the previous revision that corrected a
> > maximum of 24 bits by sector, as some register addresses overlap.
> >
> > Using information from the device tree, we can configure the driver to
> > work with both versions.
> >
> > Signed-off-by: Romain Izard <romain.izard.pro@gmail.com>
> > ---
> > .../devicetree/bindings/mtd/atmel-nand.txt | 7 +++++--
> > drivers/mtd/nand/atmel_nand.c | 23 +++++++++++++++++++++-
> > drivers/mtd/nand/atmel_nand_ecc.h | 8 ++++++--
> > 3 files changed, 33 insertions(+), 5 deletions(-)
> >
> > diff --git a/Documentation/devicetree/bindings/mtd/atmel-nand.txt
> > b/Documentation/devicetree/bindings/mtd/atmel-nand.txt
> > index 89b0db9801b0..90887b430f03 100644
> > --- a/Documentation/devicetree/bindings/mtd/atmel-nand.txt
> > +++ b/Documentation/devicetree/bindings/mtd/atmel-nand.txt
> > @@ -1,7 +1,10 @@
> > Atmel NAND flash
> >
> > Required properties:
> > -- compatible : should be "atmel,at91rm9200-nand" or "atmel,sama5d4-nand".
> > +- compatible: The possible values are:
> > + "atmel,at91rm9200-nand"
> > + "atmel,sama5d2-nand"
> > + "atmel,sama5d4-nand"
> > - reg : should specify localbus address and size used for the chip,
> > and hardware ECC controller if available.
> > If the hardware ECC is PMECC, it should contain address and size for
> > @@ -22,7 +25,7 @@ Optional properties:
> > Supported values are: "none", "soft", "hw", "hw_syndrome", "hw_oob_first",
> > "soft_bch".
> > - atmel,has-pmecc : boolean to enable Programmable Multibit ECC hardware.
> > - Only supported by at91sam9x5 or later sam9 product.
> > + Supported by AT91SAM9x5 or later SAM9 chips, and SAMA5 chips.
>
> What compatible string would AT91SAM9x5 be?

"atmel,at91rm9200-nand".

>
> > - atmel,pmecc-cap : error correct capability for Programmable Multibit ECC
> > Controller. Supported values are: 2, 4, 8, 12, 24.
> > - atmel,pmecc-sector-size : sector size for ECC computation.
> > Supported values

Best Regards,
Wenyou Yang