Re: [PATCH v4 1/3] dt-bindings: arm: qcom: document qcom,msm-id and qcom,board-id

From: Krzysztof Kozlowski
Date: Fri Jun 24 2022 - 13:56:59 EST

On 24/06/2022 19:26, Rob Herring wrote:
> On Thu, 23 Jun 2022 12:53:59 +0200, Krzysztof Kozlowski wrote:
>> The top level qcom,msm-id and qcom,board-id properties are utilized by
>> bootloaders on Qualcomm MSM platforms to determine which device tree
>> should be used and passed to the kernel.
>>
>> The commit b32e592d3c28 ("devicetree: bindings: Document qcom board
>> compatible format") from 2015 was a consensus during discussion about
>> upstreaming qcom,msm-id and qcom,board-id fields. There are however still
>> problems with that consensus:
>> 1. It was reached 7 years ago but it turned out its implementation did
>> not reach all possible products.
>>
>> 2. Initially additional tool (dtbTool) was needed for parsing these
>> fields to create a QCDT image consisting of multiple DTBs, later the
>> bootloaders were improved and they use these qcom,msm-id and
>> qcom,board-id properties directly.
>>
>> 3. Extracting relevant information from the board compatible requires
>> this additional tool (dtbTool), which makes the build process more
>> complicated and not easily reproducible (DTBs are modified after the
>> kernel build).
>>
>> 4. Some versions of Qualcomm bootloaders expect these properties even
>> when booting with a single DTB. The community is stuck with these
>> bootloaders thus they require properties in the DTBs.
>>
>> Since several upstreamed Qualcomm SoC-based boards require these
>> properties to properly boot and the properties are reportedly used by
>> bootloaders, document them.
>>
>> Link: https://lore.kernel.org/r/a3c932d1-a102-ce18-deea-18cbbd05ecab@xxxxxxxxxx/
>> Co-developed-by: Kumar Gala <galak@xxxxxxxxxxxxxx>
>> Signed-off-by: Kumar Gala <galak@xxxxxxxxxxxxxx>
>> Signed-off-by: Krzysztof Kozlowski <krzysztof.kozlowski@xxxxxxxxxx>
>> Reviewed-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx>
>> ---
>> .../devicetree/bindings/arm/qcom.yaml | 121 +++++++++++++++
>> include/dt-bindings/arm/qcom,ids.h | 146 ++++++++++++++++++
>> 2 files changed, 267 insertions(+)
>> create mode 100644 include/dt-bindings/arm/qcom,ids.h
>>
>
> My bot found errors running 'make DT_CHECKER_FLAGS=-m dt_binding_check'
> on your patch (DT_CHECKER_FLAGS is new in v5.13):
>
> yamllint warnings/errors:
>
> dtschema/dtc warnings/errors:
> /builds/robherring/linux-dt-review/Documentation/devicetree/bindings/arm/qcom.yaml: properties:qcom,board-id:items: 'oneOf' conditional failed, one must be fixed:
> {'oneOf': [{'maxItems': 2, 'items': [{'description': 'Board ID consisting of three bitfields::\n - bits 31-24 - Unused\n - bits 23-16 - Platform Version Major\n - bits 15-8 - Platform Version Minor\n - bits 7-0 - Platform Type\nPlatform Type field is an exact match value. The\nPlatform Major/Minor field is a best match. The bootloader will\nlook for the closest possible match.\n'}, {'description': 'Subtype ID unique to a Platform Type/Chipset ID. For a given\nPlatform Type, there will typically only be a single board and the\nsubtype_id will be 0. However in some cases board variants may\nneed to be distinguished by different subtype_id values.\n'}]}, {'minItems': 4, 'items': [{'const': 8}, {'const': 0}, {'description': 'OnePlus board ID'}, {'description': 'OnePlus subtype ID'}]}]} is not of type 'array'
> {'maxItems': 2, 'items': [{'description': 'Board ID consisting of three bitfields::\n - bits 31-24 - Unused\n - bits 23-16 - Platform Version Major\n - bits 15-8 - Platform Version Minor\n - bits 7-0 - Platform Type\nPlatform Type field is an exact match value. The\nPlatform Major/Minor field is a best match. The bootloader will\nlook for the closest possible match.\n'}, {'description': 'Subtype ID unique to a Platform Type/Chipset ID. For a given\nPlatform Type, there will typically only be a single board and the\nsubtype_id will be 0. However in some cases board variants may\nneed to be distinguished by different subtype_id values.\n'}]} should not be valid under {'required': ['maxItems']}
> hint: "maxItems" is not needed with an "items" list
> /builds/robherring/linux-dt-review/Documentation/devicetree/bindings/arm/qcom.yaml: properties:qcom,board-id:items:oneOf:1: 'oneOf' conditional failed, one must be fixed:
> [{'const': 8}, {'const': 0}, {'description': 'OnePlus board ID'}, {'description': 'OnePlus subtype ID'}] is too long
> [{'const': 8}, {'const': 0}, {'description': 'OnePlus board ID'}, {'description': 'OnePlus subtype ID'}] is too short
> False schema does not allow 4
> 1 was expected
> 4 is greater than the maximum of 2
> 4 is greater than the maximum of 3
> hint: "minItems" is only needed if less than the "items" list length
> from schema $id: http://devicetree.org/meta-schemas/items.yaml#

Eh, I did not see it on dtschema v2022.05-2-g4af6db61ac2b

This one I can remove.

> /builds/robherring/linux-dt-review/Documentation/devicetree/bindings/arm/qcom.yaml: properties:qcom,board-id:items:oneOf:1: 'oneOf' conditional failed, one must be fixed:
> [{'const': 8}, {'const': 0}, {'description': 'OnePlus board ID'}, {'description': 'OnePlus subtype ID'}] is too long
> [{'const': 8}, {'const': 0}, {'description': 'OnePlus board ID'}, {'description': 'OnePlus subtype ID'}] is too short
> False schema does not allow 4
> 1 was expected
> 4 is greater than the maximum of 2
> 4 is greater than the maximum of 3
> hint: "minItems" is only needed if less than the "items" list length

However this one I need.

Without the minItems:4, the
arch/arm64/boot/dts/qcom/msm8996-sony-xperia-tone.dtsi matches both
conditions of oneOf.

The DTS looks like:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm64/boot/dts/qcom/msm8996-sony-xperia-tone.dtsi?id=92f20ff72066d8d7e2ffb655c2236259ac9d1c5d#n24

But I think I can code it differently:
oneOf
- items
- items
- foo
- bar
- items
- items
- foo
- bar
- baz
- faz


> from schema $id: http://devicetree.org/meta-schemas/items.yaml#
> from schema $id: http://devicetree.org/meta-schemas/keywords.yaml#
> /builds/robherring/linux-dt-review/Documentation/devicetree/bindings/arm/qcom.yaml: ignoring, error in schema: properties: qcom,board-id: items
> Documentation/devicetree/bindings/opp/opp-v2-kryo-cpu.example.dtb:0:0: /: failed to match any schema with compatible: ['arrow,apq8096-db820c', 'qcom,apq8096-sbc', 'qcom,apq8096']
> Documentation/devicetree/bindings/opp/opp-v2-kryo-cpu.example.dtb:0:0: /: failed to match any schema with compatible: ['arrow,apq8096-db820c', 'qcom,apq8096-sbc', 'qcom,apq8096']
> Documentation/devicetree/bindings/opp/opp-v2-kryo-cpu.example.dtb:0:0: /: failed to match any schema with compatible: ['arrow,apq8096-db820c', 'qcom,apq8096-sbc', 'qcom,apq8096']
>
> doc reference errors (make refcheckdocs):
>
> See https://patchwork.ozlabs.org/patch/
>
> This check can fail if there are any dependencies. The base for a patch
> series is generally the most recent rc1.
>
> If you already ran 'make dt_binding_check' and didn't see the above
> error(s), then make sure 'yamllint' is installed and dt-schema is up to
> date:
>
> pip3 install dtschema --upgrade
>
> Please check and re-submit.
>


Best regards,
Krzysztof