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

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

.../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";
  

Why not do 'compatible = "u-boot,env";' to align with normal partitions?

Or 'label'?

We have enough ways to identify things, I don't think we need another.

•        };
  

•        calibration: volume-1 {
  

Are 0 and 1 meaningful or just made up indexing?

•            volume-id = <99>;
  

•        };
  

•    };
  

• };

-- 2.34.1