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 |
|-------|--------|------|------|

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";
     };
  };
 };