0001 # SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
0002 # Copyright 2021 ARM Ltd.
0003 %YAML 1.2
0004 ---
0005 $id: http://devicetree.org/schemas/firmware/arm,scpi.yaml#
0006 $schema: http://devicetree.org/meta-schemas/core.yaml#
0007
0008 title: System Control and Power Interface (SCPI) Message Protocol bindings
0009
0010 maintainers:
0011 - Sudeep Holla <sudeep.holla@arm.com>
0012
0013 description: |
0014 Firmware implementing the SCPI described in ARM document number ARM DUI
0015 0922B ("ARM Compute Subsystem SCP: Message Interface Protocols")[0] can be
0016 used by Linux to initiate various system control and power operations.
0017
0018 This binding is intended to define the interface the firmware implementing
0019 the SCPI provide for OSPM in the device tree.
0020
0021 [0] http://infocenter.arm.com/help/topic/com.arm.doc.dui0922b/index.html
0022
0023 properties:
0024 $nodename:
0025 const: scpi
0026
0027 compatible:
0028 description:
0029 SCPI compliant firmware complying to SCPI v1.0 and above OR
0030 SCPI compliant firmware complying to all unversioned releases
0031 prior to SCPI v1.0
0032 oneOf:
0033 - const: arm,scpi # SCPI v1.0 and above
0034 - const: arm,scpi-pre-1.0 # Unversioned SCPI before v1.0
0035 - items:
0036 - enum:
0037 - amlogic,meson-gxbb-scpi
0038 - const: arm,scpi-pre-1.0
0039
0040 mboxes:
0041 description:
0042 List of phandle and mailbox channel specifiers. All the channels reserved
0043 by remote SCP firmware for use by SCPI message protocol should be
0044 specified in any order.
0045 minItems: 1
0046 maxItems: 4
0047
0048 shmem:
0049 description:
0050 List of phandle pointing to the shared memory(SHM) area between the
0051 processors using these mailboxes for IPC, one for each mailbox SHM can
0052 be any memory reserved for the purpose of this communication between the
0053 processors.
0054 minItems: 1
0055 maxItems: 4
0056
0057 power-controller:
0058 type: object
0059 description:
0060 This sub-node represents SCPI power domain controller.
0061
0062 properties:
0063 compatible:
0064 const: arm,scpi-power-domains
0065
0066 '#power-domain-cells':
0067 const: 1
0068
0069 num-domains:
0070 $ref: /schemas/types.yaml#/definitions/uint32
0071 description:
0072 Total number of power domains provided by SCPI. This is needed as
0073 the SCPI message protocol lacks a mechanism to query this
0074 information at runtime.
0075
0076 required:
0077 - compatible
0078 - '#power-domain-cells'
0079 - num-domains
0080
0081 additionalProperties: false
0082
0083 sensors:
0084 type: object
0085 description: |
0086 This sub-node represents SCPI sensors controller.
0087
0088 properties:
0089 compatible:
0090 oneOf:
0091 - const: arm,scpi-sensors
0092 - items:
0093 - enum:
0094 - amlogic,meson-gxbb-scpi-sensors
0095 - const: arm,scpi-sensors
0096
0097 '#thermal-sensor-cells':
0098 const: 1
0099
0100 required:
0101 - compatible
0102 - '#thermal-sensor-cells'
0103
0104 additionalProperties: false
0105
0106 clocks:
0107 type: object
0108 description:
0109 This is the container node. Each sub-node represents one of the types
0110 of clock controller - indexed or full range.
0111
0112 properties:
0113 compatible:
0114 const: arm,scpi-clocks
0115
0116 patternProperties:
0117 "^clocks-[0-9a-f]+$":
0118 type: object
0119 description: |
0120 This sub-node represents one of the types of clock controller
0121 - indexed or full range.
0122
0123 "arm,scpi-dvfs-clocks" - all the clocks that are variable and index
0124 based. These clocks don't provide an entire range of values between
0125 the limits but only discrete points within the range. The firmware
0126 provides the mapping for each such operating frequency and the index
0127 associated with it. The firmware also manages the voltage scaling
0128 appropriately with the clock scaling.
0129
0130 "arm,scpi-variable-clocks" - all the clocks that are variable and
0131 provide full range within the specified range. The firmware provides
0132 the range of values within a specified range.
0133
0134 properties:
0135 compatible:
0136 enum:
0137 - arm,scpi-dvfs-clocks
0138 - arm,scpi-variable-clocks
0139
0140 '#clock-cells':
0141 const: 1
0142
0143 clock-output-names: true
0144
0145 clock-indices:
0146 $ref: /schemas/types.yaml#/definitions/uint32-array
0147 description:
0148 The identifying number for the clocks(i.e.clock_id) in the node.
0149 It can be non linear and hence provide the mapping of identifiers
0150 into the clock-output-names array.
0151
0152 required:
0153 - compatible
0154 - '#clock-cells'
0155 - clock-output-names
0156 - clock-indices
0157
0158 additionalProperties: false
0159
0160 required:
0161 - compatible
0162
0163 additionalProperties: false
0164
0165 additionalProperties: false
0166
0167 required:
0168 - compatible
0169 - mboxes
0170 - shmem
0171
0172 examples:
0173 - |
0174 firmware {
0175 scpi {
0176 compatible = "arm,scpi";
0177 mboxes = <&mhuA 1>;
0178 shmem = <&cpu_scp_hpri>; /* HP-NonSecure */
0179
0180 scpi_devpd: power-controller {
0181 compatible = "arm,scpi-power-domains";
0182 num-domains = <2>;
0183 #power-domain-cells = <1>;
0184 };
0185
0186 clocks {
0187 compatible = "arm,scpi-clocks";
0188
0189 scpi_dvfs: clocks-0 {
0190 compatible = "arm,scpi-dvfs-clocks";
0191 #clock-cells = <1>;
0192 clock-indices = <0>, <1>, <2>;
0193 clock-output-names = "atlclk", "aplclk","gpuclk";
0194 };
0195
0196 scpi_clk: clocks-1 {
0197 compatible = "arm,scpi-variable-clocks";
0198 #clock-cells = <1>;
0199 clock-indices = <3>, <4>;
0200 clock-output-names = "pxlclk0", "pxlclk1";
0201 };
0202 };
0203
0204 scpi_sensors: sensors {
0205 compatible = "arm,scpi-sensors";
0206 #thermal-sensor-cells = <1>;
0207 };
0208
0209 };
0210 };
0211
0212 soc {
0213 #address-cells = <2>;
0214 #size-cells = <2>;
0215
0216 sram@50000000 {
0217 compatible = "mmio-sram";
0218 reg = <0x0 0x50000000 0x0 0x10000>;
0219
0220 #address-cells = <1>;
0221 #size-cells = <1>;
0222 ranges = <0 0x0 0x50000000 0x10000>;
0223
0224 cpu_scp_lpri: scp-sram-section@0 {
0225 compatible = "arm,scp-shmem";
0226 reg = <0x0 0x200>;
0227 };
0228
0229 cpu_scp_hpri: scp-sram-section@200 {
0230 compatible = "arm,scp-shmem";
0231 reg = <0x200 0x200>;
0232 };
0233 };
0234 };
0235
0236 - |
0237 firmware {
0238 scpi {
0239 compatible = "amlogic,meson-gxbb-scpi", "arm,scpi-pre-1.0";
0240 mboxes = <&mailbox 1>, <&mailbox 2>;
0241 shmem = <&cpu_scp_lpri>, <&cpu_scp_hpri>;
0242
0243 scpi_sensors1: sensors {
0244 compatible = "amlogic,meson-gxbb-scpi-sensors", "arm,scpi-sensors";
0245 #thermal-sensor-cells = <1>;
0246 };
0247 };
0248 };
0249 ...
