Documentation/devicetree/bindings/interconnect/mediatek,cci.yaml

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

title: MediaTek Cache Coherent Interconnect (CCI) frequency and voltage scaling

maintainers:
  - Jia-Wei Chang <jia-wei.chang@mediatek.com>
  - Johnson Wang <johnson.wang@mediatek.com>

description: |
  MediaTek Cache Coherent Interconnect (CCI) is a hardware engine used by
  MT8183 and MT8186 SoCs to scale the frequency and adjust the voltage in
  hardware. It can also optimize the voltage to reduce the power consumption.

properties:
  compatible:
    oneOf:
      - enum:
          - mediatek,mt8183-cci
          - mediatek,mt8186-cci
      - items:
          - enum:
              - mediatek,mt7988-cci
          - const: mediatek,mt8183-cci

  clocks:
    items:
      - description:
          The multiplexer for clock input of the bus.
      - description:
          A parent of "bus" clock which is used as an intermediate clock source
          when the original clock source (PLL) is under transition and not
          stable yet.

  clock-names:
    items:
      - const: cci
      - const: intermediate

  operating-points-v2: true
  opp-table:
    type: object

  proc-supply:
    description:
      Phandle of the regulator for CCI that provides the supply voltage.

  sram-supply:
    description:
      Phandle of the regulator for sram of CCI that provides the supply
      voltage. When it is present, the implementation needs to do
      "voltage tracking" to step by step scale up/down Vproc and Vsram to fit
      SoC specific needs. When absent, the voltage scaling flow is handled by
      hardware, hence no software "voltage tracking" is needed.

required:
  - compatible
  - clocks
  - clock-names
  - operating-points-v2
  - proc-supply

additionalProperties: false

examples:
  - |
    #include <dt-bindings/clock/mt8183-clk.h>
    cci: cci {
        compatible = "mediatek,mt8183-cci";
        clocks = <&mcucfg CLK_MCU_BUS_SEL>,
                 <&topckgen CLK_TOP_ARMPLL_DIV_PLL1>;
        clock-names = "cci", "intermediate";
        operating-points-v2 = <&cci_opp>;
        proc-supply = <&mt6358_vproc12_reg>;
    };

    cci_opp: opp-table-cci {
        compatible = "operating-points-v2";
        opp-shared;
        opp2_00: opp-273000000 {
            opp-hz = /bits/ 64 <273000000>;
            opp-microvolt = <650000>;
        };
        opp2_01: opp-338000000 {
            opp-hz = /bits/ 64 <338000000>;
            opp-microvolt = <687500>;
        };
        opp2_02: opp-403000000 {
            opp-hz = /bits/ 64 <403000000>;
            opp-microvolt = <718750>;
        };
        opp2_03: opp-463000000 {
            opp-hz = /bits/ 64 <463000000>;
            opp-microvolt = <756250>;
        };
        opp2_04: opp-546000000 {
            opp-hz = /bits/ 64 <546000000>;
            opp-microvolt = <800000>;
        };
        opp2_05: opp-624000000 {
            opp-hz = /bits/ 64 <624000000>;
            opp-microvolt = <818750>;
        };
        opp2_06: opp-689000000 {
            opp-hz = /bits/ 64 <689000000>;
            opp-microvolt = <850000>;
        };
        opp2_07: opp-767000000 {
            opp-hz = /bits/ 64 <767000000>;
            opp-microvolt = <868750>;
        };
        opp2_08: opp-845000000 {
            opp-hz = /bits/ 64 <845000000>;
            opp-microvolt = <893750>;
        };
        opp2_09: opp-871000000 {
            opp-hz = /bits/ 64 <871000000>;
            opp-microvolt = <906250>;
        };
        opp2_10: opp-923000000 {
            opp-hz = /bits/ 64 <923000000>;
            opp-microvolt = <931250>;
        };
        opp2_11: opp-962000000 {
            opp-hz = /bits/ 64 <962000000>;
            opp-microvolt = <943750>;
        };
        opp2_12: opp-1027000000 {
            opp-hz = /bits/ 64 <1027000000>;
            opp-microvolt = <975000>;
        };
        opp2_13: opp-1092000000 {
            opp-hz = /bits/ 64 <1092000000>;
            opp-microvolt = <1000000>;
        };
        opp2_14: opp-1144000000 {
            opp-hz = /bits/ 64 <1144000000>;
            opp-microvolt = <1025000>;
        };
        opp2_15: opp-1196000000 {
            opp-hz = /bits/ 64 <1196000000>;
            opp-microvolt = <1050000>;
        };
    };