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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.
+
+
+Generic compatible values and properties
+----------------------------------------
+
+Required properties:
+ - compatible: Must be at least one of the vendor-specific compatible values
+ from a vendor-specific section below, and "simple-bus" as a
+ fallback.
+ - #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.
+
+
+Vendor-specific compatible values and properties
+------------------------------------------------
+
+Renesas Bus State Controller (BSC):
+ - compatible: Must be an SoC-specific value, and "renesas,bsc" as a fallback.
+ SoC-specific values can be:
+ "renesas,bsc-r8a73a4" for R-Mobile APE6 (r8a73a4)
+ "renesas,bsc-sh73a0" for SH-Mobile AG5 (sh73a0)
+ - reg: Must contain the base address and length to access the bus controller.
+ - interrupts: Must contain a reference to the BSC interrupt, if available.
+
+
+Example:
+
+ bsc: bus@fec10000 {
+ compatible = "renesas,bsc-sh73a0", "renesas,bsc", "simple-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>;
+ };