board/freescale/p2020ds/ddr.c

   1 /*
   2  * Copyright 2008-2009 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
  11 #include <asm/fsl_ddr_sdram.h>
  12 #include <asm/fsl_ddr_dimm_params.h>
  13
  14 typedef struct {
  15         u32 datarate_mhz_low;
  16         u32 datarate_mhz_high;
  17         u32 n_ranks;
  18         u32 clk_adjust;
  19         u32 cpo;
  20         u32 write_data_delay;
  21         u32 force_2T;
  22 } board_specific_parameters_t;
  23
  24 /* ranges for parameters:
  25  *  wr_data_delay = 0-6
  26  *  clk adjust = 0-8
  27  *  cpo 2-0x1E (30)
  28  */
  29
  30 const board_specific_parameters_t board_specific_parameters[][20] = {
  31         {
  32         /*      memory controller 0                     */
  33         /*        lo|  hi|  num|  clk| cpo|wrdata|2T    */
  34         /*       mhz| mhz|ranks|adjst|    | delay|      */
  35 #ifdef CONFIG_FSL_DDR2
  36                 {  0, 333,    2,    4,   0x1f,    2,  0},
  37                 {334, 400,    2,    4,   0x1f,    2,  0},
  38                 {401, 549,    2,    4,   0x1f,    2,  0},
  39                 {550, 680,    2,    4,   0x1f,    3,  0},
  40                 {681, 850,    2,    4,   0x1f,    4,  0},
  41                 {  0, 333,    1,    4,   0x1f,    2,  0},
  42                 {334, 400,    1,    4,   0x1f,    2,  0},
  43                 {401, 549,    1,    4,   0x1f,    2,  0},
  44                 {550, 680,    1,    4,   0x1f,    3,  0},
  45                 {681, 850,    1,    4,   0x1f,    4,  0}
  46 #else
  47                 {  0, 850,    2,    6,   0x1f,    4,  0},
  48                 {  0, 850,    1,    4,   0x1f,    4,  0}
  49 #endif
  50         },
  51 };
  52
  53 void fsl_ddr_board_options(memctl_options_t *popts,
  54                                 dimm_params_t *pdimm,
  55                                 unsigned int ctrl_num)
  56 {
  57         const board_specific_parameters_t *pbsp =
  58                                 &(board_specific_parameters[ctrl_num][0]);
  59         u32 num_params = sizeof(board_specific_parameters[ctrl_num]) /
  60                                 sizeof(board_specific_parameters[0][0]);
  61         u32 i;
  62         ulong ddr_freq;
  63
  64         /* set odt_rd_cfg and odt_wr_cfg. If the there is only one dimm in
  65          * that controller, set odt_wr_cfg to 4 for CS0, and 0 to CS1. If
  66          * there are two dimms in the controller, set odt_rd_cfg to 3 and
  67          * odt_wr_cfg to 3 for the even CS, 0 for the odd CS.
  68          */
  69         for (i = 0; i < CONFIG_CHIP_SELECTS_PER_CTRL; i++) {
  70                         popts->cs_local_opts[i].odt_rd_cfg = 0;
  71                         popts->cs_local_opts[i].odt_wr_cfg = 1;
  72         }
  73
  74         /* Get clk_adjust, cpo, write_data_delay,2T, according to the board ddr
  75          * freqency and n_banks specified in board_specific_parameters table.
  76          */
  77         ddr_freq = get_ddr_freq(0) / 1000000;
  78         for (i = 0; i < num_params; i++) {
  79                 if (ddr_freq >= pbsp->datarate_mhz_low &&
  80                     ddr_freq <= pbsp->datarate_mhz_high &&
  81                     pdimm->n_ranks == pbsp->n_ranks) {
  82                         popts->clk_adjust = pbsp->clk_adjust;
  83                         popts->cpo_override = pbsp->cpo;
  84                         popts->write_data_delay = pbsp->write_data_delay;
  85                         popts->twoT_en = pbsp->force_2T;
  86                 }
  87                 pbsp++;
  88         }
  89
  90         /*
  91          * Factors to consider for half-strength driver enable:
  92          *      - number of DIMMs installed
  93          */
  94         popts->half_strength_driver_enable = 0;
  95         popts->wrlvl_en = 1;
  96         /* Write leveling override */
  97         popts->wrlvl_override = 1;
  98         popts->wrlvl_sample = 0xa;
  99         popts->wrlvl_start = 0x8;
 100         /* Rtt and Rtt_WR override */
 101         popts->rtt_override = 1;
 102         popts->rtt_override_value = DDR3_RTT_120_OHM;
 103         popts->rtt_wr_override_value = 0; /* Rtt_WR= dynamic ODT off */
 104 }