The NAND chips in MTD have a bunch of generic options that are needed in a device tree. Add a YAML schemas for those. Signed-off-by: Maxime Ripard <maxime.ripard@xxxxxxxxxxx> --- Documentation/devicetree/bindings/mtd/nand-controller.yaml | 131 +++++++- 1 file changed, 131 insertions(+) create mode 100644 Documentation/devicetree/bindings/mtd/nand-controller.yaml diff --git a/Documentation/devicetree/bindings/mtd/nand-controller.yaml b/Documentation/devicetree/bindings/mtd/nand-controller.yaml new file mode 100644 index 000000000000..05b1afb34972 --- /dev/null +++ b/Documentation/devicetree/bindings/mtd/nand-controller.yaml @@ -0,0 +1,131 @@ +# SPDX-License-Identifier: (GPL-2.0+ OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/mtd/nand-controller.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: NAND Chip and NAND Controller Generic Binding + +maintainers: + - Boris Brezillon <bbrezillon@xxxxxxxxxx> + - Miquel Raynal <miquel.raynal@xxxxxxxxxxx> + - Richard Weinberger <richard@xxxxxx> + +description: | + The NAND controller should be represented with its own DT node, and + all NAND chips attached to this controller should be defined as + children nodes of the NAND controller. This representation should be + enforced even for simple controllers supporting only one chip. + + The ECC strength and ECC step size properties define the correction + capability of a controller. Together, they say a controller can + correct {strength} bit errors per {size} bytes. + + The interpretation of these parameters is implementation-defined, so + not all implementations must support all possible + combinations. However, implementations are encouraged to further + specify the value(s) they support. + +properties: + $nodename: + pattern: "^nand-controller(@.*)?" + + "#address-cells": + const: 1 + + "#size-cells": + const: 0 + + ranges: true + +patternProperties: + "^nand@[a-z0-9]$": + properties: + reg: + description: + Contains the native Ready/Busy IDs. + + nand-ecc-mode: + allOf: + - $ref: /schemas/types.yaml#/definitions/string + - enum: [ none, soft, hw, hw_syndrome, hw_oob_first, on-die ] + description: + Operation mode of the NAND ecc mode. soft_bch is deprecated + and should be replaced by soft and nand-ecc-algo + + nand-ecc-algo: + allOf: + - $ref: /schemas/types.yaml#/definitions/string + - enum: [ hamming, bch, rs ] + description: + Algorithm of NAND ECC. + + nand-bus-width: + allOf: + - $ref: /schemas/types.yaml#/definitions/uint32 + - enum: [ 8, 16 ] + - default: 8 + description: + Bus width to the NAND chip + + nand-on-flash-bbt: + $ref: /schemas/types.yaml#/definitions/flag + description: + Enable the on-flash Bad Block Table + + nand-ecc-strength: + $ref: /schemas/types.yaml#/definitions/uint32 + description: + Number of bits to correct per ECC step. + + nand-ecc-step-size: + $ref: /schemas/types.yaml#/definitions/uint32 + description: + Number of data bytes covered by a single ECC step. + + nand-ecc-maximize: + $ref: /schemas/types.yaml#/definitions/flag + description: + Whether or not the ECC strength should be maximized. The + maximum ECC strength is both controller and chip + dependent. The controller side has to select the ECC config + providing the best strength and taking the OOB area size + constraint into account. This is particularly useful when + only the in-band area is used by the upper layers, and you + want to make your NAND as reliable as possible. + + nand-is-boot-medium: + $ref: /schemas/types.yaml#/definitions/flag + description: + Whether or not the NAND chip is a boot medium. Drivers might + use this information to select ECC algorithms supported by + the boot ROM or similar restrictions. + + nand-rb: + $ref: /schemas/types.yaml#/definitions/uint32-array + description: + Contains the native Ready/Busy IDs. + + required: + - reg + +required: + - "#address-cells" + - "#size-cells" + +examples: + - | + nand-controller { + #address-cells = <1>; + #size-cells = <0>; + + /* controller specific properties */ + + nand@0 { + reg = <0>; + nand-ecc-mode = "soft"; + nand-ecc-algo = "bch"; + + /* controller specific properties */ + }; + }; base-commit: aa63f222af3e5991099ebcecca7c474d8285c7c4 -- git-series 0.9.1
