xref: /openbmc/u-boot/board/freescale/p2041rdb/ddr.c (revision e91610da)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright 2011 Freescale Semiconductor, Inc.
4  */
5 
6 #include <common.h>
7 #include <i2c.h>
8 #include <hwconfig.h>
9 #include <asm/mmu.h>
10 #include <fsl_ddr_sdram.h>
11 #include <fsl_ddr_dimm_params.h>
12 #include <asm/fsl_law.h>
13 
14 DECLARE_GLOBAL_DATA_PTR;
15 
16 struct board_specific_parameters {
17 	u32 n_ranks;
18 	u32 datarate_mhz_high;
19 	u32 clk_adjust;
20 	u32 wrlvl_start;
21 	u32 cpo;
22 	u32 write_data_delay;
23 	u32 force_2t;
24 };
25 
26 /*
27  * This table contains all valid speeds we want to override with board
28  * specific parameters. datarate_mhz_high values need to be in ascending order
29  * for each n_ranks group.
30  *
31  * ranges for parameters:
32  *  wr_data_delay = 0-6
33  *  clk adjust = 0-8
34  *  cpo 2-0x1E (30)
35  */
36 static const struct board_specific_parameters dimm0[] = {
37 	/*
38 	 * memory controller 0
39 	 *   num|  hi|  clk| wrlvl | cpo  |wrdata|2T
40 	 * ranks| mhz|adjst| start | delay|
41 	 */
42 	{2,   750,    3,     5,   0xff,    2,  0},
43 	{2,  1250,    4,     6,   0xff,    2,  0},
44 	{2,  1350,    5,     7,   0xff,    2,  0},
45 	{2,  1666,    5,     8,   0xff,    2,  0},
46 	{}
47 };
48 
49 void fsl_ddr_board_options(memctl_options_t *popts,
50 				dimm_params_t *pdimm,
51 				unsigned int ctrl_num)
52 {
53 	const struct board_specific_parameters *pbsp, *pbsp_highest = NULL;
54 	ulong ddr_freq;
55 
56 	if (ctrl_num) {
57 		printf("Wrong parameter for controller number %d", ctrl_num);
58 		return;
59 	}
60 	if (!pdimm->n_ranks)
61 		return;
62 
63 	pbsp = dimm0;
64 
65 	/*
66 	 * Get clk_adjust, cpo, write_data_delay,2T, according to the board ddr
67 	 * freqency and n_banks specified in board_specific_parameters table.
68 	 */
69 	ddr_freq = get_ddr_freq(0) / 1000000;
70 	while (pbsp->datarate_mhz_high) {
71 		if (pbsp->n_ranks == pdimm->n_ranks) {
72 			if (ddr_freq <= pbsp->datarate_mhz_high) {
73 				popts->cpo_override = pbsp->cpo;
74 				popts->write_data_delay =
75 					pbsp->write_data_delay;
76 				popts->clk_adjust = pbsp->clk_adjust;
77 				popts->wrlvl_start = pbsp->wrlvl_start;
78 				popts->twot_en = pbsp->force_2t;
79 				goto found;
80 			}
81 			pbsp_highest = pbsp;
82 		}
83 		pbsp++;
84 	}
85 
86 	if (pbsp_highest) {
87 		printf("Error: board specific timing not found "
88 			"for data rate %lu MT/s!\n"
89 			"Trying to use the highest speed (%u) parameters\n",
90 			ddr_freq, pbsp_highest->datarate_mhz_high);
91 		popts->cpo_override = pbsp_highest->cpo;
92 		popts->write_data_delay = pbsp_highest->write_data_delay;
93 		popts->clk_adjust = pbsp_highest->clk_adjust;
94 		popts->wrlvl_start = pbsp_highest->wrlvl_start;
95 		popts->twot_en = pbsp_highest->force_2t;
96 	} else {
97 		panic("DIMM is not supported by this board");
98 	}
99 
100 found:
101 	/*
102 	 * Factors to consider for half-strength driver enable:
103 	 *	- number of DIMMs installed
104 	 */
105 	popts->half_strength_driver_enable = 0;
106 	/* Write leveling override */
107 	popts->wrlvl_override = 1;
108 	popts->wrlvl_sample = 0xf;
109 
110 	/* Rtt and Rtt_WR override */
111 	popts->rtt_override = 0;
112 
113 	/* Enable ZQ calibration */
114 	popts->zq_en = 1;
115 
116 	/* DHC_EN =1, ODT = 60 Ohm */
117 	popts->ddr_cdr1 = DDR_CDR1_DHC_EN;
118 }
119 
120 int dram_init(void)
121 {
122 	phys_size_t dram_size = 0;
123 
124 	puts("Initializing....");
125 
126 	if (fsl_use_spd()) {
127 		puts("using SPD\n");
128 		dram_size = fsl_ddr_sdram();
129 	} else {
130 		puts("no SPD and fixed parameters\n");
131 		return -ENXIO;
132 	}
133 
134 	dram_size = setup_ddr_tlbs(dram_size / 0x100000);
135 	dram_size *= 0x100000;
136 
137 	debug("    DDR: ");
138 	gd->ram_size = dram_size;
139 
140 	return 0;
141 }
142