xref: /openbmc/u-boot/board/freescale/p2041rdb/ddr.c (revision c6af2e7d)
1 /*
2  * Copyright 2011 Freescale Semiconductor, Inc.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * Version 2 as published by the Free Software Foundation.
7  */
8 
9 #include <common.h>
10 #include <i2c.h>
11 #include <hwconfig.h>
12 #include <asm/mmu.h>
13 #include <asm/fsl_ddr_sdram.h>
14 #include <asm/fsl_ddr_dimm_params.h>
15 #include <asm/fsl_law.h>
16 
17 struct board_specific_parameters {
18 	u32 n_ranks;
19 	u32 datarate_mhz_high;
20 	u32 clk_adjust;
21 	u32 wrlvl_start;
22 	u32 cpo;
23 	u32 write_data_delay;
24 	u32 force_2T;
25 };
26 
27 /*
28  * This table contains all valid speeds we want to override with board
29  * specific parameters. datarate_mhz_high values need to be in ascending order
30  * for each n_ranks group.
31  *
32  * ranges for parameters:
33  *  wr_data_delay = 0-6
34  *  clk adjust = 0-8
35  *  cpo 2-0x1E (30)
36  */
37 static const struct board_specific_parameters dimm0[] = {
38 	/*
39 	 * memory controller 0
40 	 *   num|  hi|  clk| wrlvl | cpo  |wrdata|2T
41 	 * ranks| mhz|adjst| start | delay|
42 	 */
43 	{2,   750,    3,     5,   0xff,    2,  0},
44 	{2,  1250,    4,     6,   0xff,    2,  0},
45 	{2,  1350,    5,     7,   0xff,    2,  0},
46 	{2,  1666,    5,     8,   0xff,    2,  0},
47 	{}
48 };
49 
50 void fsl_ddr_board_options(memctl_options_t *popts,
51 				dimm_params_t *pdimm,
52 				unsigned int ctrl_num)
53 {
54 	const struct board_specific_parameters *pbsp, *pbsp_highest = NULL;
55 	ulong ddr_freq;
56 
57 	if (ctrl_num) {
58 		printf("Wrong parameter for controller number %d", ctrl_num);
59 		return;
60 	}
61 	if (!pdimm->n_ranks)
62 		return;
63 
64 	pbsp = dimm0;
65 
66 	/*
67 	 * Get clk_adjust, cpo, write_data_delay,2T, according to the board ddr
68 	 * freqency and n_banks specified in board_specific_parameters table.
69 	 */
70 	ddr_freq = get_ddr_freq(0) / 1000000;
71 	while (pbsp->datarate_mhz_high) {
72 		if (pbsp->n_ranks == pdimm->n_ranks) {
73 			if (ddr_freq <= pbsp->datarate_mhz_high) {
74 				popts->cpo_override = pbsp->cpo;
75 				popts->write_data_delay =
76 					pbsp->write_data_delay;
77 				popts->clk_adjust = pbsp->clk_adjust;
78 				popts->wrlvl_start = pbsp->wrlvl_start;
79 				popts->twoT_en = pbsp->force_2T;
80 				goto found;
81 			}
82 			pbsp_highest = pbsp;
83 		}
84 		pbsp++;
85 	}
86 
87 	if (pbsp_highest) {
88 		printf("Error: board specific timing not found "
89 			"for data rate %lu MT/s!\n"
90 			"Trying to use the highest speed (%u) parameters\n",
91 			ddr_freq, pbsp_highest->datarate_mhz_high);
92 		popts->cpo_override = pbsp_highest->cpo;
93 		popts->write_data_delay = pbsp_highest->write_data_delay;
94 		popts->clk_adjust = pbsp_highest->clk_adjust;
95 		popts->wrlvl_start = pbsp_highest->wrlvl_start;
96 		popts->twoT_en = pbsp_highest->force_2T;
97 	} else {
98 		panic("DIMM is not supported by this board");
99 	}
100 
101 found:
102 	/*
103 	 * Factors to consider for half-strength driver enable:
104 	 *	- number of DIMMs installed
105 	 */
106 	popts->half_strength_driver_enable = 0;
107 	/* Write leveling override */
108 	popts->wrlvl_override = 1;
109 	popts->wrlvl_sample = 0xf;
110 
111 	/* Rtt and Rtt_WR override */
112 	popts->rtt_override = 0;
113 
114 	/* Enable ZQ calibration */
115 	popts->zq_en = 1;
116 
117 	/* DHC_EN =1, ODT = 60 Ohm */
118 	popts->ddr_cdr1 = DDR_CDR1_DHC_EN;
119 }
120 
121 phys_size_t initdram(int board_type)
122 {
123 	phys_size_t dram_size = 0;
124 
125 	puts("Initializing....");
126 
127 	if (fsl_use_spd()) {
128 		puts("using SPD\n");
129 		dram_size = fsl_ddr_sdram();
130 	} else {
131 		puts("no SPD and fixed parameters\n");
132 		return dram_size;
133 	}
134 
135 	dram_size = setup_ddr_tlbs(dram_size / 0x100000);
136 	dram_size *= 0x100000;
137 
138 	debug("    DDR: ");
139 	return dram_size;
140 }
141