Commit Graph

8 Commits

Author SHA1 Message Date
Thomas Petazzoni
85f94b5ef0 dt-bindings: mtd: document new "on-die" nand-ecc-mode
A number of NAND chips support a feature called on-die ECC, where the
NAND chip itself is capable of doing error detection and correction. The
new "on-die" value for nand-ecc-mode indicates that we want this
functionality to be used.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Acked-by: Rob Herring <robh@kernel.org>
Reviewed-by: Richard Weinberger <richard@nod.at>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2017-05-15 13:18:24 +02:00
Boris Brezillon
ba78ee00e1 mtd: nand: Add an option to maximize the ECC strength
The generic NAND DT bindings allows one to tweak the ECC strength and
step size to their need. It can be used to lower the ECC strength to
match a bootloader/firmware config, but might also be used to get a better
reliability.

In the latter case, the user might want to use the maximum ECC strength
without having to explicitly calculate the exact value (this value not
only depends on the OOB size, but also on the NAND controller, and can
be tricky to extract).

Add a generic 'nand-ecc-maximize' DT property and the associated
NAND_ECC_MAXIMIZE flag, to let ECC controller drivers select the best
ECC strength and step-size on their own.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Rob Herring <robh@kernel.org>
2016-09-23 09:35:16 +02:00
Baruch Siach
507e617440 Documentation: dt: mtd: drop "soft_bch" from example
Commit 32698aafc9 (Documentation: devicetree: deprecate "soft_bch"
nand-ecc-mode value, 2016-04-22) deprecated "soft_bch". Update the example to
match.

Signed-off-by: Baruch Siach <baruch@tkos.co.il>
Acked-by: Rafał Miłecki <zajec5@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2016-05-27 09:56:26 -07:00
Rafał Miłecki
32698aafc9 Documentation: devicetree: deprecate "soft_bch" nand-ecc-mode value
Now that we support nand-ecc-algo property it should be used together
with "soft" to specify software BCH ECC.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-05-05 23:55:14 +02:00
Rafał Miłecki
ba4f46b28f mtd: nand: add support for "nand-ecc-algo" DT property
So far it was only possible to specify ECC algorithm using "soft" and
"soft_bch" values of nand-ecc-mode prop. There wasn't a way to specify
it for a hardware ECC mode.

Now that we have independent field in NAND subsystem for storing info
about ECC algorithm we may also add support for this new DT property.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
2016-05-05 23:55:14 +02:00
Boris Brezillon
2d472aba15 mtd: nand: document the NAND controller/NAND chip DT representation
Standardize the NAND controller/NAND chip DT representation. Now, all new
NAND controller drivers should comply with this representation, even if
they are only supporting a single NAND chip.

Existing drivers can keep support for the old representation (where only
the NAND chip was described), but are encouraged to also support the new
one.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Brian Norris <computersforpeace@gmail.com>
Acked-by: Rob Herring <robh@kernel.org>
2016-04-19 22:04:51 +02:00
Ezequiel Garcia
8dd49165ef mtd: nand: Add a devicetree binding for ECC strength and ECC step size
Some flashes can only be properly accessed when the ECC mode is
specified, so a way to describe such mode is required.

Together, the ECC strength and step size define the correction capability,
so that we say we will correct "{strength} bit errors per {size} bytes".

The interpretation of these parameters is implementation-defined, but they
often have ramifications on the formation, interpretation, and placement of
correction metadata on the flash. Not all implementations must support all
possible combinations. Implementations are encouraged to further define the
value(s) they support.

Acked-by: Boris BREZILLON <b.brezillon.dev@gmail.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Signed-off-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
2014-03-10 22:42:29 -07:00
Jean-Christophe PLAGNIOL-VILLARD
770d7c39af of/mtd/nand: add generic bindings and helpers
- nand-ecc-mode : String, operation mode of the NAND ecc mode.
  Supported values are: "none", "soft", "hw", "hw_syndrome", "hw_oob_first",
  "soft_bch".
- nand-bus-width : 8 or 16 bus width if not present 8
- nand-on-flash-bbt: boolean to enable on flash bbt option if not present false

Signed-off-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@jcrosoft.com>
Acked-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: Stefan Roese <sr@denx.de>
2012-03-15 23:28:19 +08:00