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1* Generic PM domains2 3System on chip designs are often divided into multiple PM domains that can be4used for power gating of selected IP blocks for power saving by reduced leakage5current.6 7This device tree binding can be used to bind PM domain consumer devices with8their PM domains provided by PM domain providers. A PM domain provider can be9represented by any node in the device tree and can provide one or more PM10domains. A consumer node can refer to the provider by a phandle and a set of11phandle arguments (so called PM domain specifiers) of length specified by the12#power-domain-cells property in the PM domain provider node.13 14==PM domain providers==15 16See power-domain.yaml.17 18==PM domain consumers==19 20Required properties:21 - power-domains : A list of PM domain specifiers, as defined by bindings of22 the power controller that is the PM domain provider.23 24Optional properties:25 - power-domain-names : A list of power domain name strings sorted in the same26 order as the power-domains property. Consumers drivers will use27 power-domain-names to match power domains with power-domains28 specifiers.29 30Example:31 32 leaky-device@12350000 {33 compatible = "foo,i-leak-current";34 reg = <0x12350000 0x1000>;35 power-domains = <&power 0>;36 power-domain-names = "io";37 };38 39 leaky-device@12351000 {40 compatible = "foo,i-leak-current";41 reg = <0x12351000 0x1000>;42 power-domains = <&power 0>, <&power 1> ;43 power-domain-names = "io", "clk";44 };45 46The first example above defines a typical PM domain consumer device, which is47located inside a PM domain with index 0 of a power controller represented by a48node with the label "power".49In the second example the consumer device are partitioned across two PM domains,50the first with index 0 and the second with index 1, of a power controller that51is represented by a node with the label "power".52 53Optional properties:54- required-opps: This contains phandle to an OPP node in another device's OPP55 table. It may contain an array of phandles, where each phandle points to an56 OPP of a different device. It should not contain multiple phandles to the OPP57 nodes in the same OPP table. This specifies the minimum required OPP of the58 device(s), whose OPP's phandle is present in this property, for the59 functioning of the current device at the current OPP (where this property is60 present).61 62Example:63- OPP table for domain provider that provides two domains.64 65 domain0_opp_table: opp-table0 {66 compatible = "operating-points-v2";67 68 domain0_opp_0: opp-1000000000 {69 opp-hz = /bits/ 64 <1000000000>;70 opp-microvolt = <975000 970000 985000>;71 };72 domain0_opp_1: opp-1100000000 {73 opp-hz = /bits/ 64 <1100000000>;74 opp-microvolt = <1000000 980000 1010000>;75 };76 };77 78 domain1_opp_table: opp-table1 {79 compatible = "operating-points-v2";80 81 domain1_opp_0: opp-1200000000 {82 opp-hz = /bits/ 64 <1200000000>;83 opp-microvolt = <975000 970000 985000>;84 };85 domain1_opp_1: opp-1300000000 {86 opp-hz = /bits/ 64 <1300000000>;87 opp-microvolt = <1000000 980000 1010000>;88 };89 };90 91 power: power-controller@12340000 {92 compatible = "foo,power-controller";93 reg = <0x12340000 0x1000>;94 #power-domain-cells = <1>;95 operating-points-v2 = <&domain0_opp_table>, <&domain1_opp_table>;96 };97 98 leaky-device0@12350000 {99 compatible = "foo,i-leak-current";100 reg = <0x12350000 0x1000>;101 power-domains = <&power 0>;102 required-opps = <&domain0_opp_0>;103 };104 105 leaky-device1@12350000 {106 compatible = "foo,i-leak-current";107 reg = <0x12350000 0x1000>;108 power-domains = <&power 1>;109 required-opps = <&domain1_opp_1>;110 };111 112[1]. Documentation/devicetree/bindings/power/domain-idle-state.yaml113