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+Simple Power-Managed Bus
+========================
+
+A Simple Power-Managed Bus is a transparent bus that doesn't need a real
+driver, as it's typically initialized by the boot loader.
+
+However, its bus controller is part of a PM domain, or under the control of a
+functional clock. Hence, the bus controller's PM domain and/or clock must be
+enabled for child devices connected to the bus (either on-SoC or externally)
+to function.
+
+While "simple-pm-bus" follows the "simple-bus" set of properties, as specified
+in ePAPR, it is not an extension of "simple-bus".
+
+
+Required properties:
+ - compatible: Must contain at least "simple-pm-bus".
+ Must not contain "simple-bus".
+ It's recommended to let this be preceded by one or more
+ vendor-specific compatible values.
+ - #address-cells, #size-cells, ranges: Must describe the mapping between
+ parent address and child address spaces.
+
+Optional platform-specific properties for clock or PM domain control (at least
+one of them is required):
+ - clocks: Must contain a reference to the functional clock(s),
+ - power-domains: Must contain a reference to the PM domain.
+Please refer to the binding documentation for the clock and/or PM domain
+providers for more details.
+
+
+Example:
+
+ bsc: bus@fec10000 {
+ compatible = "renesas,bsc-sh73a0", "renesas,bsc",
+ "simple-pm-bus";
+ #address-cells = <1>;
+ #size-cells = <1>;
+ ranges = <0 0 0x20000000>;
+ reg = <0xfec10000 0x400>;
+ interrupts = <0 39 IRQ_TYPE_LEVEL_HIGH>;
+ clocks = <&zb_clk>;
+ power-domains = <&pd_a4s>;
+ };