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+power-mgt/psr
+------------------
+
+Some systems allow modification of how power consumption throttling
+is balanced between entities in a system. A typical one may be how the power
+management complex should balance throttling CPU versus the GPU. An OPAL
+call can be used to set these ratios, which are described in the device
+tree.
+
+In the future, there may be more available settings than just CPU
+versus GPU.
+
+Each child node in the "psr" node represents a configurable psr
+sensor.
+
+For example : ::
+        cpu-to-gpu@1
+
+The compatible property is set to "ibm,opal-power-shift-ratio".
+
+Each child node has below properties:
+
+`handle`
+  Handle to indicate the type of psr
+
+`label`
+  Name of the psr sensor
+
+The format of the handle is internal, and ``not`` ABI, although
+currently it uses the following encoding ::
+
+	| Class |Reserved|  RID	| Type |
+	|-------|--------|------|------|
+
+.. code-block:: dts
+
+   power-mgt {
+     psr {
+        compatible = "ibm,opal-power-shift-ratio";
+
+        cpu-to-gpu@0 {
+                name = "cpu-to-gpu";
+                handle = <0x00000000>;
+                label = "cpu_to_gpu_0";
+        };
+
+        cpu-to-gpu@1 {
+                name = "cpu-to-gpu";
+                handle = <0x00000100>;
+                label = "cpu_to_gpu_1";
+        };
+     };
+    };