Re: [PATCH] dt-bindings: mtd: partitions: add UBI binding

Daniel Golle
2022-06-10T12:20:06Z

On Thu, Feb 17, 2022 at 11:24:48AM +0100, Rafał Miłecki wrote:
> From: Rafał Miłecki <rafal@milecki.pl>
>
> UBI is often used on embedded devices to store UBI volumes with device
> configuration / calibration data. Such volumes may need to be documented
> and referenced for proper boot & setup.
>
> Some examples:
> 1. U-Boot environment variables
> 2. Device calibration data
> 3. Default setup (e.g. initial password)
>
> Signed-off-by: Rafał Miłecki <rafal@milecki.pl>

This is very useful and can replace the downstream hacks we are
currently using for this purpose in OpenWrt.

Reviewed-by: Daniel Golle <daniel@makrotopia.org>

> ---
> .../bindings/mtd/partitions/ubi.yaml | 67 +++++++++++++++++++
> 1 file changed, 67 insertions(+)
> create mode 100644 Documentation/devicetree/bindings/mtd/partitions/ubi.yaml
>
> diff --git a/Documentation/devicetree/bindings/mtd/partitions/ubi.yaml b/Documentation/devicetree/bindings/mtd/partitions/ubi.yaml
> new file mode 100644
> index 000000000000..cd081f06d4cb
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mtd/partitions/ubi.yaml
> @@ -0,0 +1,67 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/mtd/partitions/ubi.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: UBI (Unsorted Block Images) device
> +
> +description: |
> + UBI is a layer providing logical volumes (consisting of logical blocks) on top
> + of raw flash devices. It deals with low-level flash issues (bit-flips, bad
> + physical eraseblocks, wearing) providing a reliable data storage.
> +
> + UBI device is built and stored in a single flash partition.
> +
> + Some (usually embedded) devices use UBI volumes of specific names or indexes
> + to store setup / configuration data. This binding allows describing such
> + volumes so they can be identified and referenced by consumers.
> +
> +maintainers:
> + - Rafał Miłecki <rafal@milecki.pl>
> +
> +allOf:
> + - $ref: partition.yaml#
> +
> +properties:
> + compatible:
> + const: ubi
> +
> +patternProperties:
> + "^volume-[0-9a-f]+$":
> + type: object
> + description: UBI volume
> + properties:
> + volume-name:
> + $ref: /schemas/types.yaml#/definitions/string
> + volume-id:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + anyOf:
> + - required:
> + - volume-name
> + - required:
> + - volume-id
> +
> +unevaluatedProperties: false
> +
> +examples:
> + - |
> + partitions {
> + compatible = "fixed-partitions";
> + #address-cells = <1>;
> + #size-cells = <1>;
> +
> + partition@0 {
> + compatible = "ubi";
> + reg = <0x0000000 0x1000000>;
> + label = "filesystem";
> +
> + env: volume-0 {
> + volume-name = "u-boot-env";
> + };
> +
> + calibration: volume-1 {
> + volume-id = <99>;
> + };
> + };
> + };
> --
> 2.34.1
>