1* LPDDR3 SDRAM memories compliant to JEDEC JESD209-3C 2 3Required properties: 4- compatible : Should be "<vendor>,<type>", and generic value "jedec,lpddr3". 5 Example "<vendor>,<type>" values: 6 "samsung,K3QF2F20DB" 7 8- density : <u32> representing density in Mb (Mega bits) 9- io-width : <u32> representing bus width. Possible values are 8, 16, 32, 64 10- #address-cells: Must be set to 1 11- #size-cells: Must be set to 0 12 13Optional properties: 14 15- manufacturer-id : <u32> Manufacturer ID value read from Mode Register 5 16- revision-id : <u32 u32> Revision IDs read from Mode Registers 6 and 7 17 18The following optional properties represent the minimum value of some AC 19timing parameters of the DDR device in terms of number of clock cycles. 20These values shall be obtained from the device data-sheet. 21- tRFC-min-tck 22- tRRD-min-tck 23- tRPab-min-tck 24- tRPpb-min-tck 25- tRCD-min-tck 26- tRC-min-tck 27- tRAS-min-tck 28- tWTR-min-tck 29- tWR-min-tck 30- tRTP-min-tck 31- tW2W-C2C-min-tck 32- tR2R-C2C-min-tck 33- tWL-min-tck 34- tDQSCK-min-tck 35- tRL-min-tck 36- tFAW-min-tck 37- tXSR-min-tck 38- tXP-min-tck 39- tCKE-min-tck 40- tCKESR-min-tck 41- tMRD-min-tck 42 43Child nodes: 44- The lpddr3 node may have one or more child nodes of type "lpddr3-timings". 45 "lpddr3-timings" provides AC timing parameters of the device for 46 a given speed-bin. Please see Documentation/devicetree/ 47 bindings/ddr/lpddr3-timings.txt for more information on "lpddr3-timings" 48 49Example: 50 51samsung_K3QF2F20DB: lpddr3 { 52 compatible = "samsung,K3QF2F20DB", "jedec,lpddr3"; 53 density = <16384>; 54 io-width = <32>; 55 manufacturer-id = <1>; 56 revision-id = <123 234>; 57 #address-cells = <1>; 58 #size-cells = <0>; 59 60 tRFC-min-tck = <17>; 61 tRRD-min-tck = <2>; 62 tRPab-min-tck = <2>; 63 tRPpb-min-tck = <2>; 64 tRCD-min-tck = <3>; 65 tRC-min-tck = <6>; 66 tRAS-min-tck = <5>; 67 tWTR-min-tck = <2>; 68 tWR-min-tck = <7>; 69 tRTP-min-tck = <2>; 70 tW2W-C2C-min-tck = <0>; 71 tR2R-C2C-min-tck = <0>; 72 tWL-min-tck = <8>; 73 tDQSCK-min-tck = <5>; 74 tRL-min-tck = <14>; 75 tFAW-min-tck = <5>; 76 tXSR-min-tck = <12>; 77 tXP-min-tck = <2>; 78 tCKE-min-tck = <2>; 79 tCKESR-min-tck = <2>; 80 tMRD-min-tck = <5>; 81 82 timings_samsung_K3QF2F20DB_800mhz: lpddr3-timings@800000000 { 83 compatible = "jedec,lpddr3-timings"; 84 /* workaround: 'reg' shows max-freq */ 85 reg = <800000000>; 86 min-freq = <100000000>; 87 tRFC = <65000>; 88 tRRD = <6000>; 89 tRPab = <12000>; 90 tRPpb = <12000>; 91 tRCD = <10000>; 92 tRC = <33750>; 93 tRAS = <23000>; 94 tWTR = <3750>; 95 tWR = <7500>; 96 tRTP = <3750>; 97 tW2W-C2C = <0>; 98 tR2R-C2C = <0>; 99 tFAW = <25000>; 100 tXSR = <70000>; 101 tXP = <3750>; 102 tCKE = <3750>; 103 tCKESR = <3750>; 104 tMRD = <7000>; 105 }; 106} 107