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Documentation / devicetree / bindings / lpddr2 / lpddr2-timings.txt


Based on kernel version 4.16.1. Page generated on 2018-04-09 11:52 EST.

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	};
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