1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
|
* 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:
- manufacturer-id : <u32> Manufacturer ID value read from Mode Register 5
- revision-id : <u32 u32> Revision IDs read from Mode Registers 6 and 7
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>;
manufacturer-id = <1>;
revision-id = <123 234>;
#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>;
};
}
|
