projects / deliverable / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 274c27b1 A |
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 | }; |