[PATCH v3] dt-bindings: opp: operating-points-v2-ti-cpu: Describe opp-supported-hw

[PATCH v3] dt-bindings: opp: operating-points-v2-ti-cpu: Describe opp-supported-hw

[Dhruva Gole]

It seems like we missed migrating the complete information from the old
DT binding where we had described what the opp-supported-hw is supposed
to describe. Hence, bring back the description from the previous binding
to the current one along with a bit more context on what the values are
supposed to be.

Fixes: e576a9a8603f ("dt-bindings: cpufreq: Convert ti-cpufreq to json schema")
Signed-off-by: Dhruva Gole <d-gole@ti.com>
---

Changes in v3:
- Use the items: and then provide description for both required items.
  This tries to address Rob's comments on previous revision.
- I've not use min/max Items as the 2 descriptions items implicitly
  imply that number of bitfields needed are 2.
- Link to v2: https://lore.kernel.org/all/20240905-b4-opp-dt-binding-fix-v2-1-1e3d2a06748d@ti.com/

Changes in v2:
- Drop the patch where I updated Maintainers since it's already picked
  by Viresh.
- Add more details of how to populate the property based on device
  documents like TRM/ datasheet.
- Link to v1: https://lore.kernel.org/r/20240903-b4-opp-dt-binding-fix-v1-0-f7e186456d9f@ti.com

---
 .../opp/operating-points-v2-ti-cpu.yaml         | 17 ++++++++++++++++-
 1 file changed, 16 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/opp/operating-points-v2-ti-cpu.yaml b/Documentation/devicetree/bindings/opp/operating-points-v2-ti-cpu.yaml
index fd0c8d5c5f3e..700af89487d0 100644
--- a/Documentation/devicetree/bindings/opp/operating-points-v2-ti-cpu.yaml
+++ b/Documentation/devicetree/bindings/opp/operating-points-v2-ti-cpu.yaml
@@ -45,7 +45,22 @@ patternProperties:
       clock-latency-ns: true
       opp-hz: true
       opp-microvolt: true
-      opp-supported-hw: true
+      opp-supported-hw:
+        items:
+          - description: |
+            Which revision of the SoC the OPP is supported by.
+            This can be easily obtained from the datasheet of the
+            part being ordered/used. For eg. it will be 0x01 for SR1.0
+          - description : |
+            Which eFuse bits indicate this OPP is available.
+            The device datasheet has a table talking about Device Speed Grades.
+            If one were to sort this table and only retain the unique elements
+            of the MAXIMUM OPERATING FREQUENCY starting from the first row
+            which tells the lowest OPP, to the highest. The corresponding bits
+            need to be set based on N elements of speed grade the device supports.
+            So, if there are 3 possible unique MAXIMUM OPERATING FREQUENCY
+            in the table, then BIT(0), (1) and (2) will be set, which means
+            the value shall be 0x7.
       opp-suspend: true
       turbo-mode: true
 
-- 
2.34.1

Re: [PATCH v3] dt-bindings: opp: operating-points-v2-ti-cpu: Describe opp-supported-hw

[Rob Herring (Arm)]

On Tue, 17 Sep 2024 15:22:52 +0530, Dhruva Gole wrote:
> It seems like we missed migrating the complete information from the old
> DT binding where we had described what the opp-supported-hw is supposed
> to describe. Hence, bring back the description from the previous binding
> to the current one along with a bit more context on what the values are
> supposed to be.
> 
> Fixes: e576a9a8603f ("dt-bindings: cpufreq: Convert ti-cpufreq to json schema")
> Signed-off-by: Dhruva Gole <d-gole@ti.com>
> ---
> 
> Changes in v3:
> - Use the items: and then provide description for both required items.
>   This tries to address Rob's comments on previous revision.
> - I've not use min/max Items as the 2 descriptions items implicitly
>   imply that number of bitfields needed are 2.
> - Link to v2: https://lore.kernel.org/all/20240905-b4-opp-dt-binding-fix-v2-1-1e3d2a06748d@ti.com/
> 
> Changes in v2:
> - Drop the patch where I updated Maintainers since it's already picked
>   by Viresh.
> - Add more details of how to populate the property based on device
>   documents like TRM/ datasheet.
> - Link to v1: https://lore.kernel.org/r/20240903-b4-opp-dt-binding-fix-v1-0-f7e186456d9f@ti.com
> 
> ---
>  .../opp/operating-points-v2-ti-cpu.yaml         | 17 ++++++++++++++++-
>  1 file changed, 16 insertions(+), 1 deletion(-)
> 

My bot found errors running 'make dt_binding_check' on your patch:

yamllint warnings/errors:
./Documentation/devicetree/bindings/opp/operating-points-v2-ti-cpu.yaml:52:13: [error] syntax error: could not find expected ':' (syntax)

dtschema/dtc warnings/errors:
/builds/robherring/dt-review-ci/linux/Documentation/devicetree/bindings/opp/operating-points-v2-ti-cpu.yaml: ignoring, error parsing file
make[2]: *** Deleting file 'Documentation/devicetree/bindings/opp/operating-points-v2-ti-cpu.example.dts'
Documentation/devicetree/bindings/opp/operating-points-v2-ti-cpu.yaml:52:13: could not find expected ':'
make[2]: *** [Documentation/devicetree/bindings/Makefile:26: Documentation/devicetree/bindings/opp/operating-points-v2-ti-cpu.example.dts] Error 1
make[2]: *** Waiting for unfinished jobs....
./Documentation/devicetree/bindings/opp/operating-points-v2-ti-cpu.yaml:52:13: could not find expected ':'
make[1]: *** [/builds/robherring/dt-review-ci/linux/Makefile:1432: dt_binding_check] Error 2
make: *** [Makefile:224: __sub-make] Error 2

doc reference errors (make refcheckdocs):

See https://patchwork.ozlabs.org/project/devicetree-bindings/patch/20240917095252.1292321-1-d-gole@ti.com

The base for the series is generally the latest rc1. A different dependency
should be noted in *this* patch.

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 after running the above command yourself. Note
that DT_SCHEMA_FILES can be set to your schema file to speed up checking
your schema. However, it must be unset to test all examples with your schema.

Re: [PATCH v3] dt-bindings: opp: operating-points-v2-ti-cpu: Describe opp-supported-hw

[Rob Herring]

On Tue, Sep 17, 2024 at 03:22:52PM +0530, Dhruva Gole wrote:
> It seems like we missed migrating the complete information from the old
> DT binding where we had described what the opp-supported-hw is supposed
> to describe. Hence, bring back the description from the previous binding
> to the current one along with a bit more context on what the values are
> supposed to be.
> 
> Fixes: e576a9a8603f ("dt-bindings: cpufreq: Convert ti-cpufreq to json schema")
> Signed-off-by: Dhruva Gole <d-gole@ti.com>
> ---
> 
> Changes in v3:
> - Use the items: and then provide description for both required items.
>   This tries to address Rob's comments on previous revision.
> - I've not use min/max Items as the 2 descriptions items implicitly
>   imply that number of bitfields needed are 2.
> - Link to v2: https://lore.kernel.org/all/20240905-b4-opp-dt-binding-fix-v2-1-1e3d2a06748d@ti.com/
> 
> Changes in v2:
> - Drop the patch where I updated Maintainers since it's already picked
>   by Viresh.
> - Add more details of how to populate the property based on device
>   documents like TRM/ datasheet.
> - Link to v1: https://lore.kernel.org/r/20240903-b4-opp-dt-binding-fix-v1-0-f7e186456d9f@ti.com
> 
> ---
>  .../opp/operating-points-v2-ti-cpu.yaml         | 17 ++++++++++++++++-
>  1 file changed, 16 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/opp/operating-points-v2-ti-cpu.yaml b/Documentation/devicetree/bindings/opp/operating-points-v2-ti-cpu.yaml
> index fd0c8d5c5f3e..700af89487d0 100644
> --- a/Documentation/devicetree/bindings/opp/operating-points-v2-ti-cpu.yaml
> +++ b/Documentation/devicetree/bindings/opp/operating-points-v2-ti-cpu.yaml
> @@ -45,7 +45,22 @@ patternProperties:
>        clock-latency-ns: true
>        opp-hz: true
>        opp-microvolt: true
> -      opp-supported-hw: true
> +      opp-supported-hw:
> +        items:
> +          - description: |

Don't need '|'. If you want multiple paragraphs, then put a blank line 
in between them.

> +            Which revision of the SoC the OPP is supported by.
> +            This can be easily obtained from the datasheet of the
> +            part being ordered/used. For eg. it will be 0x01 for SR1.0
> +          - description : |
> +            Which eFuse bits indicate this OPP is available.
> +            The device datasheet has a table talking about Device Speed Grades.
> +            If one were to sort this table and only retain the unique elements
> +            of the MAXIMUM OPERATING FREQUENCY starting from the first row
> +            which tells the lowest OPP, to the highest. The corresponding bits
> +            need to be set based on N elements of speed grade the device supports.
> +            So, if there are 3 possible unique MAXIMUM OPERATING FREQUENCY
> +            in the table, then BIT(0), (1) and (2) will be set, which means
> +            the value shall be 0x7.
>        opp-suspend: true
>        turbo-mode: true
>  
> -- 
> 2.34.1
>