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Diffstat (limited to 'Documentation/devicetree/bindings/lpddr2/lpddr2-timings.txt')
-rw-r--r-- | Documentation/devicetree/bindings/lpddr2/lpddr2-timings.txt | 52 |
1 files changed, 52 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/lpddr2/lpddr2-timings.txt b/Documentation/devicetree/bindings/lpddr2/lpddr2-timings.txt new file mode 100644 index 00000000000..9ceb19e0c7f --- /dev/null +++ b/Documentation/devicetree/bindings/lpddr2/lpddr2-timings.txt | |||
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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 | }; | ||