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+* Generic PM domains
+
+System on chip designs are often divided into multiple PM domains that can be
+used for power gating of selected IP blocks for power saving by reduced leakage
+current.
+
+This device tree binding can be used to bind PM domain consumer devices with
+their PM domains provided by PM domain providers. A PM domain provider can be
+represented by any node in the device tree and can provide one or more PM
+domains. A consumer node can refer to the provider by a phandle and a set of
+phandle arguments (so called PM domain specifiers) of length specified by the
+#power-domain-cells property in the PM domain provider node.
+
+==PM domain providers==
+
+See power-domain.yaml.
+
+==PM domain consumers==
+
+Required properties:
+ - power-domains : A list of PM domain specifiers, as defined by bindings of
+ the power controller that is the PM domain provider.
+
+Optional properties:
+ - power-domain-names : A list of power domain name strings sorted in the same
+ order as the power-domains property. Consumers drivers will use
+ power-domain-names to match power domains with power-domains
+ specifiers.
+
+Example:
+
+ leaky-device@12350000 {
+ compatible = "foo,i-leak-current";
+ reg = <0x12350000 0x1000>;
+ power-domains = <&power 0>;
+ power-domain-names = "io";
+ };
+
+ leaky-device@12351000 {
+ compatible = "foo,i-leak-current";
+ reg = <0x12351000 0x1000>;
+ power-domains = <&power 0>, <&power 1> ;
+ power-domain-names = "io", "clk";
+ };
+
+The first example above defines a typical PM domain consumer device, which is
+located inside a PM domain with index 0 of a power controller represented by a
+node with the label "power".
+In the second example the consumer device are partitioned across two PM domains,
+the first with index 0 and the second with index 1, of a power controller that
+is represented by a node with the label "power".
+
+Optional properties:
+- 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:
+- OPP table for domain provider that provides two domains.
+
+ domain0_opp_table: opp-table0 {
+ compatible = "operating-points-v2";
+
+ domain0_opp_0: opp-1000000000 {
+ opp-hz = /bits/ 64 <1000000000>;
+ opp-microvolt = <975000 970000 985000>;
+ };
+ domain0_opp_1: opp-1100000000 {
+ opp-hz = /bits/ 64 <1100000000>;
+ opp-microvolt = <1000000 980000 1010000>;
+ };
+ };
+
+ domain1_opp_table: opp-table1 {
+ compatible = "operating-points-v2";
+
+ domain1_opp_0: opp-1200000000 {
+ opp-hz = /bits/ 64 <1200000000>;
+ opp-microvolt = <975000 970000 985000>;
+ };
+ domain1_opp_1: opp-1300000000 {
+ opp-hz = /bits/ 64 <1300000000>;
+ opp-microvolt = <1000000 980000 1010000>;
+ };
+ };
+
+ power: power-controller@12340000 {
+ compatible = "foo,power-controller";
+ reg = <0x12340000 0x1000>;
+ #power-domain-cells = <1>;
+ operating-points-v2 = <&domain0_opp_table>, <&domain1_opp_table>;
+ };
+
+ leaky-device0@12350000 {
+ compatible = "foo,i-leak-current";
+ reg = <0x12350000 0x1000>;
+ power-domains = <&power 0>;
+ required-opps = <&domain0_opp_0>;
+ };
+
+ leaky-device1@12350000 {
+ compatible = "foo,i-leak-current";
+ reg = <0x12350000 0x1000>;
+ power-domains = <&power 1>;
+ required-opps = <&domain1_opp_1>;
+ };
+
+[1]. Documentation/devicetree/bindings/power/domain-idle-state.yaml