xref: /freebsd-src/sys/contrib/device-tree/Bindings/memory-controllers/ddr/lpddr2-timings.txt (revision 8cc087a1eee9ec1ca9f7ac1e63ad51bdb5a682eb)
1*8cc087a1SEmmanuel Vadot* AC timing parameters of LPDDR2(JESD209-2) memories for a given speed-bin
2*8cc087a1SEmmanuel Vadot
3*8cc087a1SEmmanuel VadotRequired properties:
4*8cc087a1SEmmanuel Vadot- compatible : Should be "jedec,lpddr2-timings"
5*8cc087a1SEmmanuel Vadot- min-freq : minimum DDR clock frequency for the speed-bin. Type is <u32>
6*8cc087a1SEmmanuel Vadot- max-freq : maximum DDR clock frequency for the speed-bin. Type is <u32>
7*8cc087a1SEmmanuel Vadot
8*8cc087a1SEmmanuel VadotOptional properties:
9*8cc087a1SEmmanuel Vadot
10*8cc087a1SEmmanuel VadotThe following properties represent AC timing parameters from the memory
11*8cc087a1SEmmanuel Vadotdata-sheet of the device for a given speed-bin. All these properties are
12*8cc087a1SEmmanuel Vadotof type <u32> and the default unit is ps (pico seconds). Parameters with
13*8cc087a1SEmmanuel Vadota different unit have a suffix indicating the unit such as 'tRAS-max-ns'
14*8cc087a1SEmmanuel Vadot- tRCD
15*8cc087a1SEmmanuel Vadot- tWR
16*8cc087a1SEmmanuel Vadot- tRAS-min
17*8cc087a1SEmmanuel Vadot- tRRD
18*8cc087a1SEmmanuel Vadot- tWTR
19*8cc087a1SEmmanuel Vadot- tXP
20*8cc087a1SEmmanuel Vadot- tRTP
21*8cc087a1SEmmanuel Vadot- tDQSCK-max
22*8cc087a1SEmmanuel Vadot- tFAW
23*8cc087a1SEmmanuel Vadot- tZQCS
24*8cc087a1SEmmanuel Vadot- tZQinit
25*8cc087a1SEmmanuel Vadot- tRPab
26*8cc087a1SEmmanuel Vadot- tZQCL
27*8cc087a1SEmmanuel Vadot- tCKESR
28*8cc087a1SEmmanuel Vadot- tRAS-max-ns
29*8cc087a1SEmmanuel Vadot- tDQSCK-max-derated
30*8cc087a1SEmmanuel Vadot
31*8cc087a1SEmmanuel VadotExample:
32*8cc087a1SEmmanuel Vadot
33*8cc087a1SEmmanuel Vadottimings_elpida_ECB240ABACN_400mhz: lpddr2-timings@0 {
34*8cc087a1SEmmanuel Vadot	compatible	= "jedec,lpddr2-timings";
35*8cc087a1SEmmanuel Vadot	min-freq	= <10000000>;
36*8cc087a1SEmmanuel Vadot	max-freq	= <400000000>;
37*8cc087a1SEmmanuel Vadot	tRPab		= <21000>;
38*8cc087a1SEmmanuel Vadot	tRCD		= <18000>;
39*8cc087a1SEmmanuel Vadot	tWR		= <15000>;
40*8cc087a1SEmmanuel Vadot	tRAS-min	= <42000>;
41*8cc087a1SEmmanuel Vadot	tRRD		= <10000>;
42*8cc087a1SEmmanuel Vadot	tWTR		= <7500>;
43*8cc087a1SEmmanuel Vadot	tXP		= <7500>;
44*8cc087a1SEmmanuel Vadot	tRTP		= <7500>;
45*8cc087a1SEmmanuel Vadot	tCKESR		= <15000>;
46*8cc087a1SEmmanuel Vadot	tDQSCK-max	= <5500>;
47*8cc087a1SEmmanuel Vadot	tFAW		= <50000>;
48*8cc087a1SEmmanuel Vadot	tZQCS		= <90000>;
49*8cc087a1SEmmanuel Vadot	tZQCL		= <360000>;
50*8cc087a1SEmmanuel Vadot	tZQinit		= <1000000>;
51*8cc087a1SEmmanuel Vadot	tRAS-max-ns	= <70000>;
52*8cc087a1SEmmanuel Vadot};
53