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

[Gaurav Kohli]

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 | 53 +++++++++++++++++++++-
 1 file changed, 52 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/thermal/thermal-zones.yaml b/Documentation/devicetree/bindings/thermal/thermal-zones.yaml
index 999ad40a20d5..cbe72c2ef87c 100644
--- a/Documentation/devicetree/bindings/thermal/thermal-zones.yaml
+++ b/Documentation/devicetree/bindings/thermal/thermal-zones.yaml
@@ -152,6 +152,51 @@ patternProperties:
                 situation where the trip gets constantly triggered soon after
                 cooling action is removed.
 
+            temperature-bin:
+              $ref: /schemas/types.yaml#/definitions/int32-array
+              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.
+                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.
+
+                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.
+              items:
+                minItems: 1
+                maxItems: 4
+
             type:
               $ref: /schemas/types.yaml#/definitions/string
               enum:
@@ -179,8 +224,14 @@ patternProperties:
                 The active trip type can be used to control other HW to
                 help in cooling e.g. fans can be sped up or slowed down
 
+          oneOf:
+            - required:
+                - temperature
+            - required:
+                - temperature-bin
+          dependentRequired:
+            temperature-bin: [thermal-hw-bin]
           required:
-            - temperature
             - hysteresis
             - type
 

-- 
2.34.1