Re: [RFC PATCH v2 1/8] dt-bindings: block: add basic bindings for block devices

[Rob Herring]

On Tue, Mar 05, 2024 at 08:23:20PM +0000, Daniel Golle wrote:
> Add bindings for block devices which are used to allow referencing
> nvmem bits on them.
> 
> Signed-off-by: Daniel Golle <daniel@xxxxxxxxxxxxxx>
> ---
>  .../bindings/block/block-device.yaml          | 22 ++++++++
>  .../devicetree/bindings/block/partition.yaml  | 51 +++++++++++++++++++
>  .../devicetree/bindings/block/partitions.yaml | 20 ++++++++
>  3 files changed, 93 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/block/block-device.yaml
>  create mode 100644 Documentation/devicetree/bindings/block/partition.yaml
>  create mode 100644 Documentation/devicetree/bindings/block/partitions.yaml
> 
> diff --git a/Documentation/devicetree/bindings/block/block-device.yaml b/Documentation/devicetree/bindings/block/block-device.yaml
> new file mode 100644
> index 0000000000000..c83ea525650ba
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/block/block-device.yaml
> @@ -0,0 +1,22 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/block/block-device.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: block storage device
> +
> +description: |
> +  This binding is generic and describes a block-oriented storage device.
> +
> +maintainers:
> +  - Daniel Golle <daniel@xxxxxxxxxxxxxx>
> +
> +properties:
> +  partitions:
> +    $ref: /schemas/block/partitions.yaml
> +
> +  nvmem-layout:
> +    $ref: /schemas/nvmem/layouts/nvmem-layout.yaml#
> +
> +unevaluatedProperties: false
> diff --git a/Documentation/devicetree/bindings/block/partition.yaml b/Documentation/devicetree/bindings/block/partition.yaml
> new file mode 100644
> index 0000000000000..df561dd33cbc9
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/block/partition.yaml
> @@ -0,0 +1,51 @@
> +# SPDX-License-Identifier: GPL-2.0-only OR BSD-2-Clause
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/block/partition.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: Partition on a block device
> +
> +description: |
> +  This binding describes a partition on a block storage device.
> +  Partitions may be matched by a combination of partition number, name,
> +  and UUID.
> +
> +maintainers:
> +  - Daniel Golle <daniel@xxxxxxxxxxxxxx>
> +
> +properties:
> +  $nodename:
> +    pattern: '^block-partition-.+$'
> +
> +  partnum:
> +    $ref: /schemas/types.yaml#/definitions/uint32
> +    description:
> +      Matches partition by number if present.
> +
> +  partname:
> +    $ref: /schemas/types.yaml#/definitions/string
> +    description:
> +      Matches partition by PARTNAME if present.

Why do we need something new here? The existing fixed-partitions can 
already define block device partitions. It just matches by 
address/offset which works whether its MBR or GPT. Also, in DT we always 
have an address when there is an address.

I'm sure you want to statically define this and have it work even if the 
partitions move, but sorry...

> +
> +  uuid:
> +    $ref: /schemas/types.yaml#/definitions/string
> +    description:
> +      Matches partition by PARTUUID if present.

If this remains it will need some work in the dtschema tools. The reason 
is json-schema already has support for UUIDs as a defined 'format' key 
value and we should use that.

> +
> +  nvmem-layout:
> +    $ref: /schemas/nvmem/layouts/nvmem-layout.yaml#
> +    description:
> +      This container may reference an NVMEM layout parser.
> +
> +anyOf:
> +  - required:
> +      - partnum
> +
> +  - required:
> +      - partname
> +
> +  - required:
> +      - uuid
> +
> +unevaluatedProperties: false