board/freescale/p2041rdb/ddr.c

   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 <fsl_ddr_sdram.h>
  14 #include <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 }