Re: [PATCH v2 1/6] dt-bindings: thermal: thermal-zones: add hardware-binning trip properties

[Krzysztof Kozlowski]

On Sat, Oct 31, 2026 at 06:52:47PM +0530, Gaurav Kohli wrote:
> From: Amit Kucheria <amit.kucheria@xxxxxxxxxxxxxxxx>
> 
> Differences in SoC packaging can be used to provide multiple SoC SKUs at
> different thermal and performance characteristics. The underlying SoC
> remains the same except for how much heat the packaging can dissipate,
> thereby influencing the critical trip point at which an SoC SKU needs to
> be throttled. This SKU-specific data is typically burned into fuses
> during manufacturing and can be read back at runtime.
> 
> Add two optional trip-point properties to describe this:
> 
>   - 'temperature-bin': an array of per-bin trip temperatures, used
>     instead of 'temperature' when the trip depends on the hardware
>     revision encoded in fuses.
> 
>   - 'thermal-hw-bin': one or more bitmask groups describing the hardware
>     revisions for which a trip point is valid, modeled on the
>     'opp-supported-hw' property of the OPP framework.
> 
> Signed-off-by: Amit Kucheria <amit.kucheria@xxxxxxxxxxxxxxxx>
> Signed-off-by: Gaurav Kohli <gaurav.kohli@xxxxxxxxxxxxxxxx>
> ---
>  .../devicetree/bindings/thermal/thermal-zones.yaml | 57 +++++++++++++++++++++-
>  1 file changed, 56 insertions(+), 1 deletion(-)
> 
> diff --git a/Documentation/devicetree/bindings/thermal/thermal-zones.yaml b/Documentation/devicetree/bindings/thermal/thermal-zones.yaml
> index 999ad40a20d5..62590dfc77bf 100644
> --- a/Documentation/devicetree/bindings/thermal/thermal-zones.yaml
> +++ b/Documentation/devicetree/bindings/thermal/thermal-zones.yaml
> @@ -152,6 +152,55 @@ patternProperties:
>                  situation where the trip gets constantly triggered soon after
>                  cooling action is removed.
>  
> +            temperature-bin:
> +              $ref: /schemas/types.yaml#/definitions/int32-array
> +              items:
> +                minimum: -273000
> +                maximum: 200000
> +              description: |
> +                An array of integers expressing trip temperatures in
> +                millicelsius, one entry per hardware bin sub-group defined
> +                in the thermal-hw-bin property.  Each value is the trip
> +                temperature for the corresponding hardware bin.
> +
> +                Use this property instead of 'temperature' when the trip
> +                temperature depends on the SoC hardware revision as encoded
> +                in fuse values.  The platform driver reads the fuse and
> +                registers the hardware-version bitfields with the thermal
> +                zone; the framework then selects the matching entry.
> +
> +                Exactly one of 'temperature' or 'temperature-bin' must be
> +                present in each trip node.
> +
> +            thermal-hw-bin:
> +              $ref: /schemas/types.yaml#/definitions/uint32-matrix
> +              description: |
> +                Optional bitmask(s) describing the hardware revisions for
> +                which this trip point is valid.
> +
> +                Uses the same format and semantics as the opp-supported-hw
> +                property in the OPP framework.  The platform provides N
> +                32-bit values describing the hardware it is running on.

', in a format specific to the thermal sensor provided in
"thermal-sensors" property.'

This basically ties it to the thermal sensor which will disallow growing
the thermal-sensors to more than one phandle. The plural in
"thermal-sensors" name is confusing...

> +                Each trip node may provide one or more groups of N 32-bit
> +                mask values.
> +
> +                The total number of 32-bit cells must be a multiple of N.
> +                Each contiguous group of N cells forms a sub-group.  A
> +                sub-group matches if, for all i in [0 .. N-1], the bitwise
> +                AND of the i-th mask and the i-th platform hardware value
> +                is non-zero.  The trip point is enabled if any sub-group
> +                matches.  If multiple sub-groups match, the first matching
> +                sub-group selects the corresponding temperature-bin entry.
> +
> +                When used together with 'temperature-bin', the number of
> +                sub-groups must equal the number of entries in
> +                'temperature-bin'.
> +
> +                If absent, the trip point is valid for all hardware.

minItems: 1
maxItems: 32

Best regards,
Krzysztof