diff --git a/Documentation/devicetree/bindings/power/opp.txt b/Documentation/devicetree/bindings/power/opp.txt index 259bf00edf7d..3d5d32ca0f97 100644 --- a/Documentation/devicetree/bindings/power/opp.txt +++ b/Documentation/devicetree/bindings/power/opp.txt @@ -45,10 +45,21 @@ 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. +Devices may want to choose OPP tables at runtime and so can provide a list of +phandles here. But only *one* of them should be chosen at runtime. This must be +accompanied by a corresponding "operating-points-names" property, to uniquely +identify the OPP tables. + If required, this can be extended for SoC vendor specfic bindings. Such bindings should be documented as Documentation/devicetree/bindings/power/-opp.txt and should have a compatible description like: "operating-points-v2-". +Optional properties: +- operating-points-names: Names of OPP tables (required if multiple OPP + tables are present), to uniquely identify them. The same list must be present + for all the CPUs which are sharing clock/voltage rails and hence the OPP + tables. + * OPP Table Node This describes the OPPs belonging to a device. This node can have following @@ -68,6 +79,8 @@ Optional properties: Missing property means devices have independent clock/voltage/current lines, but they share OPP tables. +- status: Marks the OPP table enabled/disabled. + * OPP Node @@ -396,3 +409,50 @@ Example 4: Handling multiple regulators }; }; }; + +Example 5: Multiple OPP tables + +/ { + cpus { + cpu@0 { + compatible = "arm,cortex-a7"; + ... + + cpu-supply = <&cpu_supply> + operating-points-v2 = <&cpu0_opp_table_slow>, <&cpu0_opp_table_fast>; + operating-points-names = "slow", "fast"; + }; + }; + + cpu0_opp_table_slow: opp_table_slow { + compatible = "operating-points-v2"; + status = "okay"; + opp-shared; + + opp00 { + opp-hz = <600000000>; + ... + }; + + opp01 { + opp-hz = <800000000>; + ... + }; + }; + + cpu0_opp_table_fast: opp_table_fast { + compatible = "operating-points-v2"; + status = "okay"; + opp-shared; + + opp10 { + opp-hz = <1000000000>; + ... + }; + + opp11 { + opp-hz = <1100000000>; + ... + }; + }; +};