| * LPDDR3 SDRAM memories compliant to JEDEC JESD209-3C |
| |
| Required properties: |
| - compatible : Should be "<vendor>,<type>", and generic value "jedec,lpddr3". |
| Example "<vendor>,<type>" values: |
| "samsung,K3QF2F20DB" |
| |
| - density : <u32> representing density in Mb (Mega bits) |
| - io-width : <u32> representing bus width. Possible values are 8, 16, 32, 64 |
| - #address-cells: Must be set to 1 |
| - #size-cells: Must be set to 0 |
| |
| Optional properties: |
| |
| The following optional properties represent the minimum value of some AC |
| timing parameters of the DDR device in terms of number of clock cycles. |
| These values shall be obtained from the device data-sheet. |
| - tRFC-min-tck |
| - tRRD-min-tck |
| - tRPab-min-tck |
| - tRPpb-min-tck |
| - tRCD-min-tck |
| - tRC-min-tck |
| - tRAS-min-tck |
| - tWTR-min-tck |
| - tWR-min-tck |
| - tRTP-min-tck |
| - tW2W-C2C-min-tck |
| - tR2R-C2C-min-tck |
| - tWL-min-tck |
| - tDQSCK-min-tck |
| - tRL-min-tck |
| - tFAW-min-tck |
| - tXSR-min-tck |
| - tXP-min-tck |
| - tCKE-min-tck |
| - tCKESR-min-tck |
| - tMRD-min-tck |
| |
| Child nodes: |
| - The lpddr3 node may have one or more child nodes of type "lpddr3-timings". |
| "lpddr3-timings" provides AC timing parameters of the device for |
| a given speed-bin. Please see Documentation/devicetree/ |
| bindings/ddr/lpddr3-timings.txt for more information on "lpddr3-timings" |
| |
| Example: |
| |
| samsung_K3QF2F20DB: lpddr3 { |
| compatible = "samsung,K3QF2F20DB", "jedec,lpddr3"; |
| density = <16384>; |
| io-width = <32>; |
| #address-cells = <1>; |
| #size-cells = <0>; |
| |
| tRFC-min-tck = <17>; |
| tRRD-min-tck = <2>; |
| tRPab-min-tck = <2>; |
| tRPpb-min-tck = <2>; |
| tRCD-min-tck = <3>; |
| tRC-min-tck = <6>; |
| tRAS-min-tck = <5>; |
| tWTR-min-tck = <2>; |
| tWR-min-tck = <7>; |
| tRTP-min-tck = <2>; |
| tW2W-C2C-min-tck = <0>; |
| tR2R-C2C-min-tck = <0>; |
| tWL-min-tck = <8>; |
| tDQSCK-min-tck = <5>; |
| tRL-min-tck = <14>; |
| tFAW-min-tck = <5>; |
| tXSR-min-tck = <12>; |
| tXP-min-tck = <2>; |
| tCKE-min-tck = <2>; |
| tCKESR-min-tck = <2>; |
| tMRD-min-tck = <5>; |
| |
| timings_samsung_K3QF2F20DB_800mhz: lpddr3-timings@800000000 { |
| compatible = "jedec,lpddr3-timings"; |
| /* workaround: 'reg' shows max-freq */ |
| reg = <800000000>; |
| min-freq = <100000000>; |
| tRFC = <65000>; |
| tRRD = <6000>; |
| tRPab = <12000>; |
| tRPpb = <12000>; |
| tRCD = <10000>; |
| tRC = <33750>; |
| tRAS = <23000>; |
| tWTR = <3750>; |
| tWR = <7500>; |
| tRTP = <3750>; |
| tW2W-C2C = <0>; |
| tR2R-C2C = <0>; |
| tFAW = <25000>; |
| tXSR = <70000>; |
| tXP = <3750>; |
| tCKE = <3750>; |
| tCKESR = <3750>; |
| tMRD = <7000>; |
| }; |
| } |
