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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
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Adding upstream version 5.10.209.upstream/5.10.209
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
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+Generic OPP (Operating Performance Points) Bindings
+----------------------------------------------------
+
+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 document contain multiple versions of OPP binding and only one of them
+should be used per device.
+
+Binding 1: operating-points
+============================
+
+This binding only supports voltage-frequency pairs.
+
+Properties:
+- operating-points: An array of 2-tuples items, and each item consists
+ of frequency and voltage like <freq-kHz vol-uV>.
+ freq: clock frequency in kHz
+ vol: voltage in microvolt
+
+Examples:
+
+cpu@0 {
+ compatible = "arm,cortex-a9";
+ reg = <0>;
+ next-level-cache = <&L2>;
+ operating-points = <
+ /* kHz uV */
+ 792000 1100000
+ 396000 950000
+ 198000 850000
+ >;
+};
+
+
+Binding 2: operating-points-v2
+============================
+
+* Property: operating-points-v2
+
+Devices supporting OPPs must set their "operating-points-v2" property with
+phandle to a OPP table in their DT node. The OPP core will use this phandle to
+find the operating points for the device.
+
+This can contain more than one phandle for power domain providers that provide
+multiple power domains. That is, one phandle for each power domain. If only one
+phandle is available, then the same OPP table will be used for all power domains
+provided by the power domain provider.
+
+If required, this can be extended for SoC vendor specific bindings. Such bindings
+should be documented as Documentation/devicetree/bindings/power/<vendor>-opp.txt
+and should have a compatible description like: "operating-points-v2-<vendor>".
+
+* OPP Table Node
+
+This describes the OPPs belonging to a device. This node can have following
+properties:
+
+Required properties:
+- compatible: Allow OPPs to express their compatibility. It should be:
+ "operating-points-v2".
+
+- OPP nodes: 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.
+
+Optional properties:
+- opp-shared: 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.
+
+- status: Marks the OPP table enabled/disabled.
+
+
+* OPP Node
+
+This defines voltage-current-frequency combinations along with other related
+properties.
+
+Required properties:
+- opp-hz: 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.
+
+- opp-peak-kBps: 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.
+
+Optional properties:
+- opp-microvolt: voltage in micro Volts.
+
+ 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.
+
+- opp-microvolt-<name>: 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.
+
+- opp-microamp: 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 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.
+
+- opp-microamp-<name>: Named opp-microamp property. Similar to
+ opp-microvolt-<name> property, but for microamp instead.
+
+- opp-level: A value representing the performance level of the device,
+ expressed as a 32-bit integer.
+
+- opp-avg-kBps: 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.
+
+- clock-latency-ns: Specifies the maximum possible transition latency (in
+ nanoseconds) for switching to this OPP from any other OPP.
+
+- turbo-mode: 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.
+
+- opp-suspend: 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.
+
+- opp-supported-hw: 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.
+
+- status: Marks the node enabled/disabled.
+
+- required-opps: 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).
+
+Example 1: Single cluster Dual-core ARM cortex A9, switch DVFS states together.
+
+/ {
+ cpus {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ cpu@0 {
+ compatible = "arm,cortex-a9";
+ reg = <0>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 0>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply0>;
+ operating-points-v2 = <&cpu0_opp_table>;
+ };
+
+ cpu@1 {
+ compatible = "arm,cortex-a9";
+ reg = <1>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 0>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply0>;
+ operating-points-v2 = <&cpu0_opp_table>;
+ };
+ };
+
+ cpu0_opp_table: opp_table0 {
+ compatible = "operating-points-v2";
+ opp-shared;
+
+ opp-1000000000 {
+ opp-hz = /bits/ 64 <1000000000>;
+ opp-microvolt = <975000 970000 985000>;
+ opp-microamp = <70000>;
+ clock-latency-ns = <300000>;
+ opp-suspend;
+ };
+ opp-1100000000 {
+ opp-hz = /bits/ 64 <1100000000>;
+ opp-microvolt = <1000000 980000 1010000>;
+ opp-microamp = <80000>;
+ clock-latency-ns = <310000>;
+ };
+ opp-1200000000 {
+ opp-hz = /bits/ 64 <1200000000>;
+ opp-microvolt = <1025000>;
+ clock-latency-ns = <290000>;
+ turbo-mode;
+ };
+ };
+};
+
+Example 2: Single cluster, Quad-core Qualcom-krait, switches DVFS states
+independently.
+
+/ {
+ cpus {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ cpu@0 {
+ compatible = "qcom,krait";
+ reg = <0>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 0>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply0>;
+ operating-points-v2 = <&cpu_opp_table>;
+ };
+
+ cpu@1 {
+ compatible = "qcom,krait";
+ reg = <1>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 1>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply1>;
+ operating-points-v2 = <&cpu_opp_table>;
+ };
+
+ cpu@2 {
+ compatible = "qcom,krait";
+ reg = <2>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 2>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply2>;
+ operating-points-v2 = <&cpu_opp_table>;
+ };
+
+ cpu@3 {
+ compatible = "qcom,krait";
+ reg = <3>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 3>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply3>;
+ operating-points-v2 = <&cpu_opp_table>;
+ };
+ };
+
+ cpu_opp_table: opp_table {
+ compatible = "operating-points-v2";
+
+ /*
+ * Missing opp-shared property means CPUs switch DVFS states
+ * independently.
+ */
+
+ opp-1000000000 {
+ opp-hz = /bits/ 64 <1000000000>;
+ opp-microvolt = <975000 970000 985000>;
+ opp-microamp = <70000>;
+ clock-latency-ns = <300000>;
+ opp-suspend;
+ };
+ opp-1100000000 {
+ opp-hz = /bits/ 64 <1100000000>;
+ opp-microvolt = <1000000 980000 1010000>;
+ opp-microamp = <80000>;
+ clock-latency-ns = <310000>;
+ };
+ opp-1200000000 {
+ opp-hz = /bits/ 64 <1200000000>;
+ opp-microvolt = <1025000>;
+ opp-microamp = <90000;
+ lock-latency-ns = <290000>;
+ turbo-mode;
+ };
+ };
+};
+
+Example 3: Dual-cluster, Dual-core per cluster. CPUs within a cluster switch
+DVFS state together.
+
+/ {
+ cpus {
+ #address-cells = <1>;
+ #size-cells = <0>;
+
+ cpu@0 {
+ compatible = "arm,cortex-a7";
+ reg = <0>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 0>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply0>;
+ operating-points-v2 = <&cluster0_opp>;
+ };
+
+ cpu@1 {
+ compatible = "arm,cortex-a7";
+ reg = <1>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 0>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply0>;
+ operating-points-v2 = <&cluster0_opp>;
+ };
+
+ cpu@100 {
+ compatible = "arm,cortex-a15";
+ reg = <100>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 1>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply1>;
+ operating-points-v2 = <&cluster1_opp>;
+ };
+
+ cpu@101 {
+ compatible = "arm,cortex-a15";
+ reg = <101>;
+ next-level-cache = <&L2>;
+ clocks = <&clk_controller 1>;
+ clock-names = "cpu";
+ cpu-supply = <&cpu_supply1>;
+ operating-points-v2 = <&cluster1_opp>;
+ };
+ };
+
+ cluster0_opp: opp_table0 {
+ compatible = "operating-points-v2";
+ opp-shared;
+
+ opp-1000000000 {
+ opp-hz = /bits/ 64 <1000000000>;
+ opp-microvolt = <975000 970000 985000>;
+ opp-microamp = <70000>;
+ clock-latency-ns = <300000>;
+ opp-suspend;
+ };
+ opp-1100000000 {
+ opp-hz = /bits/ 64 <1100000000>;
+ opp-microvolt = <1000000 980000 1010000>;
+ opp-microamp = <80000>;
+ clock-latency-ns = <310000>;
+ };
+ opp-1200000000 {
+ opp-hz = /bits/ 64 <1200000000>;
+ opp-microvolt = <1025000>;
+ opp-microamp = <90000>;
+ clock-latency-ns = <290000>;
+ turbo-mode;
+ };
+ };
+
+ cluster1_opp: opp_table1 {
+ compatible = "operating-points-v2";
+ opp-shared;
+
+ opp-1300000000 {
+ opp-hz = /bits/ 64 <1300000000>;
+ opp-microvolt = <1050000 1045000 1055000>;
+ opp-microamp = <95000>;
+ clock-latency-ns = <400000>;
+ opp-suspend;
+ };
+ opp-1400000000 {
+ opp-hz = /bits/ 64 <1400000000>;
+ opp-microvolt = <1075000>;
+ opp-microamp = <100000>;
+ clock-latency-ns = <400000>;
+ };
+ opp-1500000000 {
+ opp-hz = /bits/ 64 <1500000000>;
+ opp-microvolt = <1100000 1010000 1110000>;
+ opp-microamp = <95000>;
+ clock-latency-ns = <400000>;
+ turbo-mode;
+ };
+ };
+};
+
+Example 4: Handling multiple regulators
+
+/ {
+ cpus {
+ cpu@0 {
+ compatible = "vendor,cpu-type";
+ ...
+
+ vcc0-supply = <&cpu_supply0>;
+ vcc1-supply = <&cpu_supply1>;
+ vcc2-supply = <&cpu_supply2>;
+ operating-points-v2 = <&cpu0_opp_table>;
+ };
+ };
+
+ cpu0_opp_table: opp_table0 {
+ compatible = "operating-points-v2";
+ opp-shared;
+
+ opp-1000000000 {
+ opp-hz = /bits/ 64 <1000000000>;
+ opp-microvolt = <970000>, /* Supply 0 */
+ <960000>, /* Supply 1 */
+ <960000>; /* Supply 2 */
+ opp-microamp = <70000>, /* Supply 0 */
+ <70000>, /* Supply 1 */
+ <70000>; /* Supply 2 */
+ clock-latency-ns = <300000>;
+ };
+
+ /* OR */
+
+ opp-1000000000 {
+ opp-hz = /bits/ 64 <1000000000>;
+ opp-microvolt = <975000 970000 985000>, /* Supply 0 */
+ <965000 960000 975000>, /* Supply 1 */
+ <965000 960000 975000>; /* Supply 2 */
+ opp-microamp = <70000>, /* Supply 0 */
+ <70000>, /* Supply 1 */
+ <70000>; /* Supply 2 */
+ clock-latency-ns = <300000>;
+ };
+
+ /* OR */
+
+ opp-1000000000 {
+ opp-hz = /bits/ 64 <1000000000>;
+ opp-microvolt = <975000 970000 985000>, /* Supply 0 */
+ <965000 960000 975000>, /* Supply 1 */
+ <965000 960000 975000>; /* Supply 2 */
+ opp-microamp = <70000>, /* Supply 0 */
+ <0>, /* Supply 1 doesn't need this */
+ <70000>; /* Supply 2 */
+ clock-latency-ns = <300000>;
+ };
+ };
+};
+
+Example 5: opp-supported-hw
+(example: three level hierarchy of versions: cuts, substrate and process)
+
+/ {
+ cpus {
+ cpu@0 {
+ compatible = "arm,cortex-a7";
+ ...
+
+ cpu-supply = <&cpu_supply>
+ operating-points-v2 = <&cpu0_opp_table_slow>;
+ };
+ };
+
+ opp_table {
+ compatible = "operating-points-v2";
+ opp-shared;
+
+ opp-600000000 {
+ /*
+ * Supports all substrate and process versions for 0xF
+ * cuts, i.e. only first four cuts.
+ */
+ opp-supported-hw = <0xF 0xFFFFFFFF 0xFFFFFFFF>
+ opp-hz = /bits/ 64 <600000000>;
+ ...
+ };
+
+ opp-800000000 {
+ /*
+ * Supports:
+ * - cuts: only one, 6th cut (represented by 6th bit).
+ * - substrate: supports 16 different substrate versions
+ * - process: supports 9 different process versions
+ */
+ opp-supported-hw = <0x20 0xff0000ff 0x0000f4f0>
+ opp-hz = /bits/ 64 <800000000>;
+ ...
+ };
+
+ opp-900000000 {
+ /*
+ * Supports:
+ * - All cuts and substrate where process version is 0x2.
+ * - All cuts and process where substrate version is 0x2.
+ */
+ opp-supported-hw = <0xFFFFFFFF 0xFFFFFFFF 0x02>, <0xFFFFFFFF 0x01 0xFFFFFFFF>
+ opp-hz = /bits/ 64 <900000000>;
+ ...
+ };
+ };
+};
+
+Example 6: opp-microvolt-<name>, opp-microamp-<name>:
+(example: device with two possible microvolt ranges: slow and fast)
+
+/ {
+ cpus {
+ cpu@0 {
+ compatible = "arm,cortex-a7";
+ ...
+
+ operating-points-v2 = <&cpu0_opp_table>;
+ };
+ };
+
+ cpu0_opp_table: opp_table0 {
+ compatible = "operating-points-v2";
+ opp-shared;
+
+ opp-1000000000 {
+ opp-hz = /bits/ 64 <1000000000>;
+ opp-microvolt-slow = <915000 900000 925000>;
+ opp-microvolt-fast = <975000 970000 985000>;
+ opp-microamp-slow = <70000>;
+ opp-microamp-fast = <71000>;
+ };
+
+ opp-1200000000 {
+ opp-hz = /bits/ 64 <1200000000>;
+ opp-microvolt-slow = <915000 900000 925000>, /* Supply vcc0 */
+ <925000 910000 935000>; /* Supply vcc1 */
+ opp-microvolt-fast = <975000 970000 985000>, /* Supply vcc0 */
+ <965000 960000 975000>; /* Supply vcc1 */
+ opp-microamp = <70000>; /* Will be used for both slow/fast */
+ };
+ };
+};