board/freescale/mpc8560ads/ddr.c

   1 /*
   2  * Copyright 2008 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
  12 #include <asm/fsl_ddr_sdram.h>
  13 #include <asm/fsl_ddr_dimm_params.h>
  14
  15 static void
  16 get_spd(ddr1_spd_eeprom_t *spd, unsigned char i2c_address)
  17 {
  18         i2c_read(i2c_address, 0, 1, (uchar *)spd, sizeof(ddr1_spd_eeprom_t));
  19 }
  20
  21 void
  22 fsl_ddr_get_spd(ddr1_spd_eeprom_t *ctrl_dimms_spd,
  23                       unsigned int ctrl_num)
  24 {
  25         unsigned int i;
  26         unsigned int i2c_address = 0;
  27
  28         for (i = 0; i < CONFIG_DIMM_SLOTS_PER_CTLR; i++) {
  29                 if (ctrl_num == 0 && i == 0) {
  30                         i2c_address = SPD_EEPROM_ADDRESS;
  31                 }
  32                 get_spd(&(ctrl_dimms_spd[i]), i2c_address);
  33         }
  34 }
  35
  36 void fsl_ddr_board_options(memctl_options_t *popts,
  37                                 dimm_params_t *pdimm,
  38                                 unsigned int ctrl_num)
  39 {
  40         /*
  41          * Factors to consider for CPO:
  42          *      - frequency
  43          *      - ddr1 vs. ddr2
  44          */
  45         popts->cpo_override = 0;
  46
  47         /*
  48          * Factors to consider for write data delay:
  49          *      - number of DIMMs
  50          *
  51          * 1 = 1/4 clock delay
  52          * 2 = 1/2 clock delay
  53          * 3 = 3/4 clock delay
  54          * 4 = 1   clock delay
  55          * 5 = 5/4 clock delay
  56          * 6 = 3/2 clock delay
  57          */
  58         popts->write_data_delay = 3;
  59
  60         /* 2T timing enable */
  61         popts->twoT_en = 1;
  62
  63         /*
  64          * Factors to consider for half-strength driver enable:
  65          *      - number of DIMMs installed
  66          */
  67         popts->half_strength_driver_enable = 0;
  68 }