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+Rockchip SRAM for pmu:
+------------------------------
+
+The sram of pmu is used to store the function of resume from maskrom(the 1st
+level loader). This is a common use of the "pmu-sram" because it keeps power
+even in low power states in the system.
+
+Required node properties:
+- compatible : should be "rockchip,rk3288-pmu-sram"
+- reg : physical base address and the size of the registers window
+
+Example:
+ sram@ff720000 {
+ compatible = "rockchip,rk3288-pmu-sram", "mmio-sram";
+ reg = <0xff720000 0x1000>;
+ };