linux/Documentation/devicetree/bindings/lpddr2/lpddr2-timings.txt
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   1* AC timing parameters of LPDDR2(JESD209-2) memories for a given speed-bin
   2
   3Required properties:
   4- compatible : Should be "jedec,lpddr2-timings"
   5- min-freq : minimum DDR clock frequency for the speed-bin. Type is <u32>
   6- max-freq : maximum DDR clock frequency for the speed-bin. Type is <u32>
   7
   8Optional properties:
   9
  10The following properties represent AC timing parameters from the memory
  11data-sheet of the device for a given speed-bin. All these properties are
  12of type <u32> and the default unit is ps (pico seconds). Parameters with
  13a different unit have a suffix indicating the unit such as 'tRAS-max-ns'
  14- tRCD
  15- tWR
  16- tRAS-min
  17- tRRD
  18- tWTR
  19- tXP
  20- tRTP
  21- tDQSCK-max
  22- tFAW
  23- tZQCS
  24- tZQinit
  25- tRPab
  26- tZQCL
  27- tCKESR
  28- tRAS-max-ns
  29- tDQSCK-max-derated
  30
  31Example:
  32
  33timings_elpida_ECB240ABACN_400mhz: lpddr2-timings@0 {
  34        compatible      = "jedec,lpddr2-timings";
  35        min-freq        = <10000000>;
  36        max-freq        = <400000000>;
  37        tRPab           = <21000>;
  38        tRCD            = <18000>;
  39        tWR             = <15000>;
  40        tRAS-min        = <42000>;
  41        tRRD            = <10000>;
  42        tWTR            = <7500>;
  43        tXP             = <7500>;
  44        tRTP            = <7500>;
  45        tCKESR          = <15000>;
  46        tDQSCK-max      = <5500>;
  47        tFAW            = <50000>;
  48        tZQCS           = <90000>;
  49        tZQCL           = <360000>;
  50        tZQinit         = <1000000>;
  51        tRAS-max-ns     = <70000>;
  52};
  53