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diff --git a/Documentation/devicetree/bindings/lpddr2/lpddr2-timings.txt b/Documentation/devicetree/bindings/lpddr2/lpddr2-timings.txt
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+* AC timing parameters of LPDDR2(JESD209-2) memories for a given speed-bin
+
+Required properties:
+- compatible : Should be "jedec,lpddr2-timings"
+- min-freq : minimum DDR clock frequency for the speed-bin. Type is <u32>
+- max-freq : maximum DDR clock frequency for the speed-bin. Type is <u32>
+
+Optional properties:
+
+The following properties represent AC timing parameters from the memory
+data-sheet of the device for a given speed-bin. All these properties are
+of type <u32> and the default unit is ps (pico seconds). Parameters with
+a different unit have a suffix indicating the unit such as 'tRAS-max-ns'
+- tRCD
+- tWR
+- tRAS-min
+- tRRD
+- tWTR
+- tXP
+- tRTP
+- tDQSCK-max
+- tFAW
+- tZQCS
+- tZQinit
+- tRPab
+- tZQCL
+- tCKESR
+- tRAS-max-ns
+- tDQSCK-max-derated
+
+Example:
+
+timings_elpida_ECB240ABACN_400mhz: lpddr2-timings@0 {
+        compatible      = "jedec,lpddr2-timings";
+        min-freq        = <10000000>;
+        max-freq        = <400000000>;
+        tRPab           = <21000>;
+        tRCD            = <18000>;
+        tWR             = <15000>;
+        tRAS-min        = <42000>;
+        tRRD            = <10000>;
+        tWTR            = <7500>;
+        tXP             = <7500>;
+        tRTP            = <7500>;
+        tCKESR          = <15000>;
+        tDQSCK-max      = <5500>;
+        tFAW            = <50000>;
+        tZQCS           = <90000>;
+        tZQCL           = <360000>;
+        tZQinit         = <1000000>;
+        tRAS-max-ns     = <70000>;
+};