| # 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 Properties |
| |
| 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: 32 |
| 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 power 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-<name> 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 |
| |
| ... |