[PATCH v4] dt-bindings: opp: operating-points-v2-ti-cpu: Describe opp-supported-hw

[PATCH v4] 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 v4:
- Fix dt_binding_check errors on previous revision.
- As per Rob's suggestion, used a blank line in between description
  and the paragraph.
- Reworded the description a bit.
- Link to v3: https://lore.kernel.org/all/20240917095252.1292321-1-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       | 20 ++++++++++++++++++-
 1 file changed, 19 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..7c07410638db 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 +45,25 @@ patternProperties:
       clock-latency-ns: true
       opp-hz: true
       opp-microvolt: true
-      opp-supported-hw: true
+      opp-supported-hw:
+        items:
+          items:
+            - description:
+
+                The 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:
+
+                The eFuse bits that indicate the particular OPP is available.
+                The device datasheet has a table talking about Device Speed Grades.
+                This table is to be sorted with only 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) | (2) will be set, which means
+                the value shall be 0x7.
       opp-suspend: true
       turbo-mode: true
 
-- 
2.34.1

Re: [PATCH v4] dt-bindings: opp: operating-points-v2-ti-cpu: Describe opp-supported-hw

[Rob Herring]

On Wed, Sep 18, 2024 at 11:03:17AM +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 v4:
> - Fix dt_binding_check errors on previous revision.
> - As per Rob's suggestion, used a blank line in between description
>   and the paragraph.
> - Reworded the description a bit.
> - Link to v3: https://lore.kernel.org/all/20240917095252.1292321-1-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       | 20 ++++++++++++++++++-
>  1 file changed, 19 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..7c07410638db 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 +45,25 @@ patternProperties:
>        clock-latency-ns: true
>        opp-hz: true
>        opp-microvolt: true
> -      opp-supported-hw: true
> +      opp-supported-hw:
> +        items:
> +          items:
> +            - description:
> +

A blank line here wasn't my suggestion. Do you see it done like this 
anywhere else in the tree?

> +                The 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

/eg./example,/

Is this 1 paragraph or 2? Put a blank line in between paragraphs if 2.

> +            - description:
> +
> +                The eFuse bits that indicate the particular OPP is available.
> +                The device datasheet has a table talking about Device Speed Grades.
> +                This table is to be sorted with only the unique elements of the
> +                MAXIMUM OPERATING FREQUENCY starting from the first row
> +                which tells the lowest OPP, to the highest. The corresponding bits

Odd line wrapping. 'which' should fit on prior line. Wrap at 80.

> +                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) | (2) will be set, which means
> +                the value shall be 0x7.

Here you should have a blank line.

>        opp-suspend: true
>        turbo-mode: true
>  
> -- 
> 2.34.1
>