lpddr2-timings.txt 1.2 KB

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