# SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause) # Copyright 2021 ARM Ltd. %YAML 1.2 --- $id: http://devicetree.org/schemas/firmware/arm,scpi.yaml# $schema: http://devicetree.org/meta-schemas/core.yaml# title: System Control and Power Interface (SCPI) Message Protocol maintainers: - Sudeep Holla description: | Firmware implementing the SCPI described in ARM document number ARM DUI 0922B ("ARM Compute Subsystem SCP: Message Interface Protocols")[0] can be used by Linux to initiate various system control and power operations. This binding is intended to define the interface the firmware implementing the SCPI provide for OSPM in the device tree. [0] http://infocenter.arm.com/help/topic/com.arm.doc.dui0922b/index.html properties: $nodename: const: scpi compatible: description: SCPI compliant firmware complying to SCPI v1.0 and above OR SCPI compliant firmware complying to all unversioned releases prior to SCPI v1.0 oneOf: - const: arm,scpi # SCPI v1.0 and above - const: arm,scpi-pre-1.0 # Unversioned SCPI before v1.0 - items: - enum: - amlogic,meson-gxbb-scpi - const: arm,scpi-pre-1.0 mboxes: description: List of phandle and mailbox channel specifiers. All the channels reserved by remote SCP firmware for use by SCPI message protocol should be specified in any order. minItems: 1 maxItems: 4 shmem: description: List of phandle pointing to the shared memory(SHM) area between the processors using these mailboxes for IPC, one for each mailbox SHM can be any memory reserved for the purpose of this communication between the processors. minItems: 1 maxItems: 4 power-controller: type: object description: This sub-node represents SCPI power domain controller. properties: compatible: const: arm,scpi-power-domains '#power-domain-cells': const: 1 num-domains: $ref: /schemas/types.yaml#/definitions/uint32 description: Total number of power domains provided by SCPI. This is needed as the SCPI message protocol lacks a mechanism to query this information at runtime. required: - compatible - '#power-domain-cells' - num-domains additionalProperties: false sensors: type: object description: | This sub-node represents SCPI sensors controller. properties: compatible: oneOf: - const: arm,scpi-sensors - items: - enum: - amlogic,meson-gxbb-scpi-sensors - const: arm,scpi-sensors '#thermal-sensor-cells': const: 1 required: - compatible - '#thermal-sensor-cells' additionalProperties: false clocks: type: object description: This is the container node. Each sub-node represents one of the types of clock controller - indexed or full range. properties: compatible: const: arm,scpi-clocks patternProperties: "^clocks-[0-9a-f]+$": type: object description: | This sub-node represents one of the types of clock controller - indexed or full range. "arm,scpi-dvfs-clocks" - all the clocks that are variable and index based. These clocks don't provide an entire range of values between the limits but only discrete points within the range. The firmware provides the mapping for each such operating frequency and the index associated with it. The firmware also manages the voltage scaling appropriately with the clock scaling. "arm,scpi-variable-clocks" - all the clocks that are variable and provide full range within the specified range. The firmware provides the range of values within a specified range. properties: compatible: enum: - arm,scpi-dvfs-clocks - arm,scpi-variable-clocks '#clock-cells': const: 1 clock-output-names: true clock-indices: $ref: /schemas/types.yaml#/definitions/uint32-array description: The identifying number for the clocks(i.e.clock_id) in the node. It can be non linear and hence provide the mapping of identifiers into the clock-output-names array. required: - compatible - '#clock-cells' - clock-output-names - clock-indices additionalProperties: false required: - compatible additionalProperties: false additionalProperties: false required: - compatible - mboxes - shmem examples: - | firmware { scpi { compatible = "arm,scpi"; mboxes = <&mhuA 1>; shmem = <&cpu_scp_hpri>; /* HP-NonSecure */ scpi_devpd: power-controller { compatible = "arm,scpi-power-domains"; num-domains = <2>; #power-domain-cells = <1>; }; clocks { compatible = "arm,scpi-clocks"; scpi_dvfs: clocks-0 { compatible = "arm,scpi-dvfs-clocks"; #clock-cells = <1>; clock-indices = <0>, <1>, <2>; clock-output-names = "atlclk", "aplclk","gpuclk"; }; scpi_clk: clocks-1 { compatible = "arm,scpi-variable-clocks"; #clock-cells = <1>; clock-indices = <3>, <4>; clock-output-names = "pxlclk0", "pxlclk1"; }; }; scpi_sensors: sensors { compatible = "arm,scpi-sensors"; #thermal-sensor-cells = <1>; }; }; }; soc { #address-cells = <2>; #size-cells = <2>; sram@50000000 { compatible = "mmio-sram"; reg = <0x0 0x50000000 0x0 0x10000>; #address-cells = <1>; #size-cells = <1>; ranges = <0 0x0 0x50000000 0x10000>; cpu_scp_lpri: scp-sram-section@0 { compatible = "arm,scp-shmem"; reg = <0x0 0x200>; }; cpu_scp_hpri: scp-sram-section@200 { compatible = "arm,scp-shmem"; reg = <0x200 0x200>; }; }; }; - | firmware { scpi { compatible = "amlogic,meson-gxbb-scpi", "arm,scpi-pre-1.0"; mboxes = <&mailbox 1>, <&mailbox 2>; shmem = <&cpu_scp_lpri>, <&cpu_scp_hpri>; scpi_sensors1: sensors { compatible = "amlogic,meson-gxbb-scpi-sensors", "arm,scpi-sensors"; #thermal-sensor-cells = <1>; }; }; }; ...