xref: /freebsd-src/sys/contrib/device-tree/Bindings/ddr/lpddr3-timings.txt (revision c66ec88fed842fbaad62c30d510644ceb7bd2d71)
1*c66ec88fSEmmanuel Vadot* AC timing parameters of LPDDR3 memories for a given speed-bin.
2*c66ec88fSEmmanuel Vadot
3*c66ec88fSEmmanuel VadotThe structures are based on LPDDR2 and extended where needed.
4*c66ec88fSEmmanuel Vadot
5*c66ec88fSEmmanuel VadotRequired properties:
6*c66ec88fSEmmanuel Vadot- compatible : Should be "jedec,lpddr3-timings"
7*c66ec88fSEmmanuel Vadot- min-freq : minimum DDR clock frequency for the speed-bin. Type is <u32>
8*c66ec88fSEmmanuel Vadot- reg : maximum DDR clock frequency for the speed-bin. Type is <u32>
9*c66ec88fSEmmanuel Vadot
10*c66ec88fSEmmanuel VadotOptional properties:
11*c66ec88fSEmmanuel Vadot
12*c66ec88fSEmmanuel VadotThe following properties represent AC timing parameters from the memory
13*c66ec88fSEmmanuel Vadotdata-sheet of the device for a given speed-bin. All these properties are
14*c66ec88fSEmmanuel Vadotof type <u32> and the default unit is ps (pico seconds).
15*c66ec88fSEmmanuel Vadot- tRFC
16*c66ec88fSEmmanuel Vadot- tRRD
17*c66ec88fSEmmanuel Vadot- tRPab
18*c66ec88fSEmmanuel Vadot- tRPpb
19*c66ec88fSEmmanuel Vadot- tRCD
20*c66ec88fSEmmanuel Vadot- tRC
21*c66ec88fSEmmanuel Vadot- tRAS
22*c66ec88fSEmmanuel Vadot- tWTR
23*c66ec88fSEmmanuel Vadot- tWR
24*c66ec88fSEmmanuel Vadot- tRTP
25*c66ec88fSEmmanuel Vadot- tW2W-C2C
26*c66ec88fSEmmanuel Vadot- tR2R-C2C
27*c66ec88fSEmmanuel Vadot- tFAW
28*c66ec88fSEmmanuel Vadot- tXSR
29*c66ec88fSEmmanuel Vadot- tXP
30*c66ec88fSEmmanuel Vadot- tCKE
31*c66ec88fSEmmanuel Vadot- tCKESR
32*c66ec88fSEmmanuel Vadot- tMRD
33*c66ec88fSEmmanuel Vadot
34*c66ec88fSEmmanuel VadotExample:
35*c66ec88fSEmmanuel Vadot
36*c66ec88fSEmmanuel Vadottimings_samsung_K3QF2F20DB_800mhz: lpddr3-timings@800000000 {
37*c66ec88fSEmmanuel Vadot	compatible	= "jedec,lpddr3-timings";
38*c66ec88fSEmmanuel Vadot	reg		= <800000000>; /* workaround: it shows max-freq */
39*c66ec88fSEmmanuel Vadot	min-freq	= <100000000>;
40*c66ec88fSEmmanuel Vadot	tRFC		= <65000>;
41*c66ec88fSEmmanuel Vadot	tRRD		= <6000>;
42*c66ec88fSEmmanuel Vadot	tRPab		= <12000>;
43*c66ec88fSEmmanuel Vadot	tRPpb		= <12000>;
44*c66ec88fSEmmanuel Vadot	tRCD		= <10000>;
45*c66ec88fSEmmanuel Vadot	tRC		= <33750>;
46*c66ec88fSEmmanuel Vadot	tRAS		= <23000>;
47*c66ec88fSEmmanuel Vadot	tWTR		= <3750>;
48*c66ec88fSEmmanuel Vadot	tWR		= <7500>;
49*c66ec88fSEmmanuel Vadot	tRTP		= <3750>;
50*c66ec88fSEmmanuel Vadot	tW2W-C2C	= <0>;
51*c66ec88fSEmmanuel Vadot	tR2R-C2C	= <0>;
52*c66ec88fSEmmanuel Vadot	tFAW		= <25000>;
53*c66ec88fSEmmanuel Vadot	tXSR		= <70000>;
54*c66ec88fSEmmanuel Vadot	tXP		= <3750>;
55*c66ec88fSEmmanuel Vadot	tCKE		= <3750>;
56*c66ec88fSEmmanuel Vadot	tCKESR		= <3750>;
57*c66ec88fSEmmanuel Vadot	tMRD		= <7000>;
58*c66ec88fSEmmanuel Vadot};
59