# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) %YAML 1.2 --- $id: http://devicetree.org/schemas/opp/opp-v2-base.yaml# $schema: http://devicetree.org/meta-schemas/core.yaml# title: Generic OPP (Operating Performance Points) Common Binding maintainers: - Viresh Kumar <viresh.kumar@linaro.org> description: | Devices work at voltage-current-frequency combinations and some implementations have the liberty of choosing these. These combinations are called Operating Performance Points aka OPPs. This document defines bindings for these OPPs applicable across wide range of devices. For illustration purpose, this document uses CPU as a device. This describes the OPPs belonging to a device. select: false properties: $nodename: pattern: '^opp-table(-[a-z0-9]+)?$' opp-shared: description: Indicates that device nodes using this OPP Table Node's phandle switch their DVFS state together, i.e. they share clock/voltage/current lines. Missing property means devices have independent clock/voltage/current lines, but they share OPP tables. type: boolean patternProperties: '^opp(-?[0-9]+)*$': type: object description: One or more OPP nodes describing voltage-current-frequency combinations. Their name isn't significant but their phandle can be used to reference an OPP. These are mandatory except for the case where the OPP table is present only to indicate dependency between devices using the opp-shared property. properties: opp-hz: description: Frequency in Hz, expressed as a 64-bit big-endian integer. This is a required property for all device nodes, unless another "required" property to uniquely identify the OPP nodes exists. Devices like power domains must have another (implementation dependent) property. Entries for multiple clocks shall be provided in the same field, as array of frequencies. The OPP binding doesn't provide any provisions to relate the values to their clocks or the order in which the clocks need to be configured and that is left for the implementation specific binding. minItems: 1 maxItems: 16 items: maxItems: 1 opp-microvolt: description: | Voltage for the OPP A single regulator's voltage is specified with an array of size one or three. Single entry is for target voltage and three entries are for <target min max> voltages. Entries for multiple regulators shall be provided in the same field separated by angular brackets <>. The OPP binding doesn't provide any provisions to relate the values to their power supplies or the order in which the supplies need to be configured and that is left for the implementation specific binding. Entries for all regulators shall be of the same size, i.e. either all use a single value or triplets. minItems: 1 maxItems: 8 # Should be enough regulators items: minItems: 1 maxItems: 3 opp-microamp: description: | The maximum current drawn by the device in microamperes considering system specific parameters (such as transients, process, aging, maximum operating temperature range etc.) as necessary. This may be used to set the most efficient regulator operating mode. Should only be set if opp-microvolt or opp-microvolt-<name> is set for the OPP. Entries for multiple regulators shall be provided in the same field separated by angular brackets <>. If current values aren't required for a regulator, then it shall be filled with 0. If current values aren't required for any of the regulators, then this field is not required. The OPP binding doesn't provide any provisions to relate the values to their power supplies or the order in which the supplies need to be configured and that is left for the implementation specific binding. minItems: 1 maxItems: 8 # Should be enough regulators opp-microwatt: description: | The power for the OPP in micro-Watts. Entries for multiple regulators shall be provided in the same field separated by angular brackets <>. If current values aren't required for a regulator, then it shall be filled with 0. If power values aren't required for any of the regulators, then this field is not required. The OPP binding doesn't provide any provisions to relate the values to their power supplies or the order in which the supplies need to be configured and that is left for the implementation specific binding. minItems: 1 maxItems: 8 # Should be enough regulators opp-level: description: A value representing the performance level of the device. $ref: /schemas/types.yaml#/definitions/uint32 opp-peak-kBps: description: Peak bandwidth in kilobytes per second, expressed as an array of 32-bit big-endian integers. Each element of the array represents the peak bandwidth value of each interconnect path. The number of elements should match the number of interconnect paths. minItems: 1 maxItems: 32 # Should be enough opp-avg-kBps: description: Average bandwidth in kilobytes per second, expressed as an array of 32-bit big-endian integers. Each element of the array represents the average bandwidth value of each interconnect path. The number of elements should match the number of interconnect paths. This property is only meaningful in OPP tables where opp-peak-kBps is present. minItems: 1 maxItems: 32 # Should be enough clock-latency-ns: description: Specifies the maximum possible transition latency (in nanoseconds) for switching to this OPP from any other OPP. turbo-mode: description: Marks the OPP to be used only for turbo modes. Turbo mode is available on some platforms, where the device can run over its operating frequency for a short duration of time limited by the device's power, current and thermal limits. type: boolean opp-suspend: description: Marks the OPP to be used during device suspend. If multiple OPPs in the table have this, the OPP with highest opp-hz will be used. type: boolean opp-supported-hw: description: | This property allows a platform to enable only a subset of the OPPs from the larger set present in the OPP table, based on the current version of the hardware (already known to the operating system). Each block present in the array of blocks in this property, represents a sub-group of hardware versions supported by the OPP. i.e. <sub-group A>, <sub-group B>, etc. The OPP will be enabled if _any_ of these sub-groups match the hardware's version. Each sub-group is a platform defined array representing the hierarchy of hardware versions supported by the platform. For a platform with three hierarchical levels of version (X.Y.Z), this field shall look like opp-supported-hw = <X1 Y1 Z1>, <X2 Y2 Z2>, <X3 Y3 Z3>. Each level (eg. X1) in version hierarchy is represented by a 32 bit value, one bit per version and so there can be maximum 32 versions per level. Logical AND (&) operation is performed for each level with the hardware's level version and a non-zero output for _all_ the levels in a sub-group means the OPP is supported by hardware. A value of 0xFFFFFFFF for each level in the sub-group will enable the OPP for all versions for the hardware. $ref: /schemas/types.yaml#/definitions/uint32-matrix maxItems: 32 items: minItems: 1 maxItems: 4 required-opps: description: This contains phandle to an OPP node in another device's OPP table. It may contain an array of phandles, where each phandle points to an OPP of a different device. It should not contain multiple phandles to the OPP nodes in the same OPP table. This specifies the minimum required OPP of the device(s), whose OPP's phandle is present in this property, for the functioning of the current device at the current OPP (where this property is present). $ref: /schemas/types.yaml#/definitions/phandle-array items: maxItems: 1 patternProperties: '^opp-microvolt-': description: Named opp-microvolt property. This is exactly similar to the above opp-microvolt property, but allows multiple voltage ranges to be provided for the same OPP. At runtime, the platform can pick a <name> and matching opp-microvolt-<name> property will be enabled for all OPPs. If the platform doesn't pick a specific <name> or the <name> doesn't match with any opp-microvolt-<name> properties, then opp-microvolt property shall be used, if present. $ref: /schemas/types.yaml#/definitions/uint32-matrix minItems: 1 maxItems: 8 # Should be enough regulators items: minItems: 1 maxItems: 3 '^opp-microamp-': description: Named opp-microamp property. Similar to opp-microvolt-<name> property, but for microamp instead. $ref: /schemas/types.yaml#/definitions/uint32-array minItems: 1 maxItems: 8 # Should be enough regulators '^opp-microwatt': description: Named opp-microwatt property. Similar to opp-microamp property, but for microwatt instead. $ref: /schemas/types.yaml#/definitions/uint32-array minItems: 1 maxItems: 8 # Should be enough regulators dependencies: opp-avg-kBps: [ opp-peak-kBps ] required: - compatible additionalProperties: true ...