xref: /OK3568_Linux_fs/u-boot/arch/arm/mach-omap2/omap4/emif.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  * EMIF programming
3*4882a593Smuzhiyun  *
4*4882a593Smuzhiyun  * (C) Copyright 2010
5*4882a593Smuzhiyun  * Texas Instruments, <www.ti.com>
6*4882a593Smuzhiyun  *
7*4882a593Smuzhiyun  * Aneesh V <aneesh@ti.com>
8*4882a593Smuzhiyun  *
9*4882a593Smuzhiyun  * SPDX-License-Identifier:	GPL-2.0+
10*4882a593Smuzhiyun  */
11*4882a593Smuzhiyun 
12*4882a593Smuzhiyun #include <common.h>
13*4882a593Smuzhiyun #include <asm/emif.h>
14*4882a593Smuzhiyun #include <asm/arch/sys_proto.h>
15*4882a593Smuzhiyun #include <asm/utils.h>
16*4882a593Smuzhiyun 
17*4882a593Smuzhiyun #ifndef CONFIG_SYS_EMIF_PRECALCULATED_TIMING_REGS
18*4882a593Smuzhiyun u32 *const T_num = (u32 *)OMAP_SRAM_SCRATCH_EMIF_T_NUM;
19*4882a593Smuzhiyun u32 *const T_den = (u32 *)OMAP_SRAM_SCRATCH_EMIF_T_DEN;
20*4882a593Smuzhiyun #endif
21*4882a593Smuzhiyun 
22*4882a593Smuzhiyun #ifdef CONFIG_SYS_DEFAULT_LPDDR2_TIMINGS
23*4882a593Smuzhiyun /* Base AC Timing values specified by JESD209-2 for 400MHz operation */
24*4882a593Smuzhiyun static const struct lpddr2_ac_timings timings_jedec_400_mhz = {
25*4882a593Smuzhiyun 	.max_freq = 400000000,
26*4882a593Smuzhiyun 	.RL = 6,
27*4882a593Smuzhiyun 	.tRPab = 21,
28*4882a593Smuzhiyun 	.tRCD = 18,
29*4882a593Smuzhiyun 	.tWR = 15,
30*4882a593Smuzhiyun 	.tRASmin = 42,
31*4882a593Smuzhiyun 	.tRRD = 10,
32*4882a593Smuzhiyun 	.tWTRx2 = 15,
33*4882a593Smuzhiyun 	.tXSR = 140,
34*4882a593Smuzhiyun 	.tXPx2 = 15,
35*4882a593Smuzhiyun 	.tRFCab = 130,
36*4882a593Smuzhiyun 	.tRTPx2 = 15,
37*4882a593Smuzhiyun 	.tCKE = 3,
38*4882a593Smuzhiyun 	.tCKESR = 15,
39*4882a593Smuzhiyun 	.tZQCS = 90,
40*4882a593Smuzhiyun 	.tZQCL = 360,
41*4882a593Smuzhiyun 	.tZQINIT = 1000,
42*4882a593Smuzhiyun 	.tDQSCKMAXx2 = 11,
43*4882a593Smuzhiyun 	.tRASmax = 70,
44*4882a593Smuzhiyun 	.tFAW = 50
45*4882a593Smuzhiyun };
46*4882a593Smuzhiyun 
47*4882a593Smuzhiyun /* Base AC Timing values specified by JESD209-2 for 200 MHz operation */
48*4882a593Smuzhiyun static const struct lpddr2_ac_timings timings_jedec_200_mhz = {
49*4882a593Smuzhiyun 	.max_freq = 200000000,
50*4882a593Smuzhiyun 	.RL = 3,
51*4882a593Smuzhiyun 	.tRPab = 21,
52*4882a593Smuzhiyun 	.tRCD = 18,
53*4882a593Smuzhiyun 	.tWR = 15,
54*4882a593Smuzhiyun 	.tRASmin = 42,
55*4882a593Smuzhiyun 	.tRRD = 10,
56*4882a593Smuzhiyun 	.tWTRx2 = 20,
57*4882a593Smuzhiyun 	.tXSR = 140,
58*4882a593Smuzhiyun 	.tXPx2 = 15,
59*4882a593Smuzhiyun 	.tRFCab = 130,
60*4882a593Smuzhiyun 	.tRTPx2 = 15,
61*4882a593Smuzhiyun 	.tCKE = 3,
62*4882a593Smuzhiyun 	.tCKESR = 15,
63*4882a593Smuzhiyun 	.tZQCS = 90,
64*4882a593Smuzhiyun 	.tZQCL = 360,
65*4882a593Smuzhiyun 	.tZQINIT = 1000,
66*4882a593Smuzhiyun 	.tDQSCKMAXx2 = 11,
67*4882a593Smuzhiyun 	.tRASmax = 70,
68*4882a593Smuzhiyun 	.tFAW = 50
69*4882a593Smuzhiyun };
70*4882a593Smuzhiyun 
71*4882a593Smuzhiyun /*
72*4882a593Smuzhiyun  * Min tCK values specified by JESD209-2
73*4882a593Smuzhiyun  * Min tCK specifies the minimum duration of some AC timing parameters in terms
74*4882a593Smuzhiyun  * of the number of cycles. If the calculated number of cycles based on the
75*4882a593Smuzhiyun  * absolute time value is less than the min tCK value, min tCK value should
76*4882a593Smuzhiyun  * be used instead. This typically happens at low frequencies.
77*4882a593Smuzhiyun  */
78*4882a593Smuzhiyun static const struct lpddr2_min_tck min_tck_jedec = {
79*4882a593Smuzhiyun 	.tRL = 3,
80*4882a593Smuzhiyun 	.tRP_AB = 3,
81*4882a593Smuzhiyun 	.tRCD = 3,
82*4882a593Smuzhiyun 	.tWR = 3,
83*4882a593Smuzhiyun 	.tRAS_MIN = 3,
84*4882a593Smuzhiyun 	.tRRD = 2,
85*4882a593Smuzhiyun 	.tWTR = 2,
86*4882a593Smuzhiyun 	.tXP = 2,
87*4882a593Smuzhiyun 	.tRTP = 2,
88*4882a593Smuzhiyun 	.tCKE = 3,
89*4882a593Smuzhiyun 	.tCKESR = 3,
90*4882a593Smuzhiyun 	.tFAW = 8
91*4882a593Smuzhiyun };
92*4882a593Smuzhiyun 
93*4882a593Smuzhiyun static const struct lpddr2_ac_timings const*
94*4882a593Smuzhiyun 			jedec_ac_timings[MAX_NUM_SPEEDBINS] = {
95*4882a593Smuzhiyun 	&timings_jedec_200_mhz,
96*4882a593Smuzhiyun 	&timings_jedec_400_mhz
97*4882a593Smuzhiyun };
98*4882a593Smuzhiyun 
99*4882a593Smuzhiyun const struct lpddr2_device_timings jedec_default_timings = {
100*4882a593Smuzhiyun 	.ac_timings = jedec_ac_timings,
101*4882a593Smuzhiyun 	.min_tck = &min_tck_jedec
102*4882a593Smuzhiyun };
103*4882a593Smuzhiyun 
emif_get_device_timings(u32 emif_nr,const struct lpddr2_device_timings ** cs0_device_timings,const struct lpddr2_device_timings ** cs1_device_timings)104*4882a593Smuzhiyun void emif_get_device_timings(u32 emif_nr,
105*4882a593Smuzhiyun 		const struct lpddr2_device_timings **cs0_device_timings,
106*4882a593Smuzhiyun 		const struct lpddr2_device_timings **cs1_device_timings)
107*4882a593Smuzhiyun {
108*4882a593Smuzhiyun 	/* Assume Identical devices on EMIF1 & EMIF2 */
109*4882a593Smuzhiyun 	*cs0_device_timings = &jedec_default_timings;
110*4882a593Smuzhiyun 	*cs1_device_timings = &jedec_default_timings;
111*4882a593Smuzhiyun }
112*4882a593Smuzhiyun #endif /* CONFIG_SYS_DEFAULT_LPDDR2_TIMINGS */
113