Documentation/devicetree/bindings/lpddr2/lpddr2-timings.txt

   1 * AC timing parameters of LPDDR2(JESD209-2) memories for a given speed-bin
   2
   3 Required 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
   8 Optional properties:
   9
  10 The following properties represent AC timing parameters from the memory
  11 data-sheet of the device for a given speed-bin. All these properties are
  12 of type <u32> and the default unit is ps (pico seconds). Parameters with
  13 a 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
  31 Example:
  32
  33 timings_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 };