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# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
%YAML 1.2
---
$id: http://devicetree.org/schemas/cpufreq/airoha,en7581-cpufreq.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

title: Airoha EN7581 CPUFreq

maintainers:
  - Christian Marangi <ansuelsmth@gmail.com>

description: |
  On newer Airoha SoC, CPU Frequency is scaled indirectly with SMC commands
  to ATF.

  A virtual clock is exposed. This virtual clock is a get-only clock and
  is used to expose the current global CPU clock. The frequency info comes
  by the output of the SMC command that reports the clock in MHz.

  The SMC sets the CPU clock by providing an index, this is modelled as
  performance states in a power domain.

  CPUs can't be individually scaled as the CPU frequency is shared across
  all CPUs and is global.

properties:
  compatible:
    const: airoha,en7581-cpufreq

  '#clock-cells':
    const: 0

  '#power-domain-cells':
    const: 0

  operating-points-v2: true

required:
  - compatible
  - '#clock-cells'
  - '#power-domain-cells'
  - operating-points-v2

additionalProperties: false

examples:
  - |
    performance-domain {
        compatible = "airoha,en7581-cpufreq";

        operating-points-v2 = <&cpu_smcc_opp_table>;

        #power-domain-cells = <0>;
        #clock-cells = <0>;
    };