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

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

[Rafał Miłecki]

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";
+            };
+
+            calibration: volume-1 {
+                volume-id = <99>;
+            };
+        };
+    };
-- 
2.34.1

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

[Rob Herring]

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
> 
> 

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

[Rafał Miłecki]

On 2.03.2022 22:59, Rob Herring wrote:
> 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?

I mean to reserve "compatible" for describing UBI volume content.

If I manage to get
[PATCH V3] dt-bindings: nvmem: add U-Boot environment variables binding
https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20220228131250.16943-1-zajec5@gmail.com/
accepted, it'll allow me to later work on something like:

env: volume-0 {
     compatible = "u-boot,env";
     volume-name = "u-boot-env";
};

(I believe) I'll need (in the final shape) two properties:
1. One for describing UBI volume ("compatible")
2. One for identifying UBI volume ("volume-name" / "volume-id")

It's similar design to the "compatible" vs. "reg" in IO hw blocks.


> Or 'label'?

I could replace "volume-name" with "label" but someone once told me that:
 > 'label' is supposed to correspond to a sticker on a port or something
 > human identifiable

;) https://patchwork.ozlabs.org/comment/2812214/

So I don't want to abuse "label" here.


> 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?

Made up indexing. I need unique nodenames but @[0-9a-f] doesn't appply here.


>> +                volume-id = <99>;
>> +            };
>> +        };
>> +    };
>> -- 
>> 2.34.1

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

[Rafał Miłecki]

Hi Rob, could you re-review my patch as I provided answers (see below), please?

On 3.03.2022 09:32, Rafał Miłecki wrote:
> On 2.03.2022 22:59, Rob Herring wrote:
>> 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?
> 
> I mean to reserve "compatible" for describing UBI volume content.
> 
> If I manage to get
> [PATCH V3] dt-bindings: nvmem: add U-Boot environment variables binding
> https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20220228131250.16943-1-zajec5@gmail.com/
> accepted, it'll allow me to later work on something like:
> 
> env: volume-0 {
>      compatible = "u-boot,env";
>      volume-name = "u-boot-env";
> };
> 
> (I believe) I'll need (in the final shape) two properties:
> 1. One for describing UBI volume ("compatible")
> 2. One for identifying UBI volume ("volume-name" / "volume-id")
> 
> It's similar design to the "compatible" vs. "reg" in IO hw blocks.
> 
> 
>> Or 'label'?
> 
> I could replace "volume-name" with "label" but someone once told me that:
>  > 'label' is supposed to correspond to a sticker on a port or something
>  > human identifiable
> 
> ;) https://patchwork.ozlabs.org/comment/2812214/
> 
> So I don't want to abuse "label" here.
> 
> 
>> 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?
> 
> Made up indexing. I need unique nodenames but @[0-9a-f] doesn't appply here.
> 
> 
>>> +                volume-id = <99>;
>>> +            };
>>> +        };
>>> +    };
>>> -- 
>>> 2.34.1

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

[Rob Herring]

On Thu, Mar 3, 2022 at 2:32 AM Rafał Miłecki <zajec5@gmail.com> wrote:
>
> On 2.03.2022 22:59, Rob Herring wrote:
> > 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?
>
> I mean to reserve "compatible" for describing UBI volume content.
>
> If I manage to get
> [PATCH V3] dt-bindings: nvmem: add U-Boot environment variables binding
> https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20220228131250.16943-1-zajec5@gmail.com/
> accepted, it'll allow me to later work on something like:
>
> env: volume-0 {
>      compatible = "u-boot,env";
>      volume-name = "u-boot-env";
> };
>
> (I believe) I'll need (in the final shape) two properties:
> 1. One for describing UBI volume ("compatible")
> 2. One for identifying UBI volume ("volume-name" / "volume-id")
>
> It's similar design to the "compatible" vs. "reg" in IO hw blocks.

That's what it is vs. what instance. You need a better example if
that's what you are trying to show. I guess if you were doing A/B
updates you'd have something like 'volume-name = "u-boot-env-b"'?

>
>
> > Or 'label'?
>
> I could replace "volume-name" with "label" but someone once told me that:
>  > 'label' is supposed to correspond to a sticker on a port or something
>  > human identifiable

Yes, it could be a human wanting to identify it. The question is
whether s/w does too.

The other aspect is there's also filesystem/partition label's. Those
are generally set by humans and opaque to the s/w. If the use is
aligned with how those labels are used, then I'd be okay with the DT
'label' here.

>
> ;) https://patchwork.ozlabs.org/comment/2812214/
>
> So I don't want to abuse "label" here.
>
>
> > 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?
>
> Made up indexing. I need unique nodenames but @[0-9a-f] doesn't appply here.

Maybe use "volume-$volumename" or "volume-$volumeid" instead?

Rob

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

[Daniel Golle]

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
>