1 /*
2  * Copyright 2011 Freescale Semiconductor, Inc.
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <common.h>
8 
9 #include <asm/fsl_ddr_sdram.h>
10 #include <asm/fsl_ddr_dimm_params.h>
11 
12 struct board_specific_parameters {
13 	u32 n_ranks;
14 	u32 datarate_mhz_high;
15 	u32 clk_adjust;
16 	u32 cpo;
17 	u32 write_data_delay;
18 	u32 force_2T;
19 };
20 
21 /*
22  * This table contains all valid speeds we want to override with board
23  * specific parameters. datarate_mhz_high values need to be in ascending order
24  * for each n_ranks group.
25  */
26 static const struct board_specific_parameters udimm0[] = {
27 	/*
28 	 * memory controller 0
29 	 *   num|  hi|  clk| cpo|wrdata|2T
30 	 * ranks| mhz|adjst|    | delay|
31 	 */
32 	{2,  300,    4,   4,    2,  0},
33 	{2,  365,    4,   6,    2,  0},
34 	{2,  450,    4,   7,    2,  0},
35 	{2,  850,    4,  31,    2,  0},
36 	{1,  300,    4,   4,    2,  0},
37 	{1,  365,    4,   6,    2,  0},
38 	{1,  450,    4,   7,    2,  0},
39 	{1,  850,    4,  31,    2,  0},
40 	{}
41 };
42 
43 void fsl_ddr_board_options(memctl_options_t *popts,
44 				dimm_params_t *pdimm,
45 				unsigned int ctrl_num)
46 {
47 	const struct board_specific_parameters *pbsp, *pbsp_highest = NULL;
48 	unsigned int i;
49 	ulong ddr_freq;
50 
51 	if (ctrl_num != 0)	/* we have only one controller */
52 		return;
53 	for (i = 0; i < CONFIG_DIMM_SLOTS_PER_CTLR; i++) {
54 		if (pdimm[i].n_ranks)
55 			break;
56 	}
57 	if (i >= CONFIG_DIMM_SLOTS_PER_CTLR)	/* no DIMM */
58 		return;
59 
60 	pbsp = udimm0;
61 
62 	/* Get clk_adjust, cpo, write_data_delay,2T, according to the board ddr
63 	 * freqency and n_banks specified in board_specific_parameters table.
64 	 */
65 	ddr_freq = get_ddr_freq(0) / 1000000;
66 	while (pbsp->datarate_mhz_high) {
67 		if (pbsp->n_ranks ==  pdimm[i].n_ranks) {
68 			if (ddr_freq <= pbsp->datarate_mhz_high) {
69 				popts->clk_adjust = pbsp->clk_adjust;
70 				popts->cpo_override = pbsp->cpo;
71 				popts->write_data_delay =
72 					pbsp->write_data_delay;
73 				popts->twoT_en = pbsp->force_2T;
74 				goto found;
75 			}
76 			pbsp_highest = pbsp;
77 		}
78 		pbsp++;
79 	}
80 
81 	if (pbsp_highest) {
82 		printf("Error: board specific timing not found "
83 			"for data rate %lu MT/s!\n"
84 			"Trying to use the highest speed (%u) parameters\n",
85 			ddr_freq, pbsp_highest->datarate_mhz_high);
86 		popts->clk_adjust = pbsp_highest->clk_adjust;
87 		popts->cpo_override = pbsp_highest->cpo;
88 		popts->write_data_delay = pbsp_highest->write_data_delay;
89 		popts->twoT_en = pbsp_highest->force_2T;
90 	} else {
91 		panic("DIMM is not supported by this board");
92 	}
93 
94 found:
95 	/*
96 	 * Factors to consider for half-strength driver enable:
97 	 *	- number of DIMMs installed
98 	 */
99 	popts->half_strength_driver_enable = 0;
100 	popts->DQS_config = 0;	/* only true DQS signal is used on board */
101 }
102