board/freescale/mpc8540ads/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
  14 static void
  15 get_spd(ddr1_spd_eeprom_t *spd, unsigned char i2c_address)
  16 {
  17         i2c_read(i2c_address, 0, 1, (uchar *)spd, sizeof(ddr1_spd_eeprom_t));
  18 }
  19
  20
  21 unsigned int
  22 fsl_ddr_get_mem_data_rate(void)
  23 {
  24         return get_ddr_freq(0);
  25 }
  26
  27
  28 void
  29 fsl_ddr_get_spd(ddr1_spd_eeprom_t *ctrl_dimms_spd,
  30                       unsigned int ctrl_num)
  31 {
  32         unsigned int i;
  33         unsigned int i2c_address = 0;
  34
  35         for (i = 0; i < CONFIG_DIMM_SLOTS_PER_CTLR; i++) {
  36                 if (ctrl_num == 0 && i == 0) {
  37                         i2c_address = SPD_EEPROM_ADDRESS;
  38                 }
  39                 get_spd(&(ctrl_dimms_spd[i]), i2c_address);
  40         }
  41 }
  42
  43 void fsl_ddr_board_options(memctl_options_t *popts, unsigned int ctrl_num)
  44 {
  45         /*
  46          * Factors to consider for CPO:
  47          *      - frequency
  48          *      - ddr1 vs. ddr2
  49          */
  50         popts->cpo_override = 0;
  51
  52         /*
  53          * Factors to consider for write data delay:
  54          *      - number of DIMMs
  55          *
  56          * 1 = 1/4 clock delay
  57          * 2 = 1/2 clock delay
  58          * 3 = 3/4 clock delay
  59          * 4 = 1   clock delay
  60          * 5 = 5/4 clock delay
  61          * 6 = 3/2 clock delay
  62          */
  63         popts->write_data_delay = 3;
  64
  65         /*
  66          * Factors to consider for half-strength driver enable:
  67          *      - number of DIMMs installed
  68          */
  69         popts->half_strength_driver_enable = 0;
  70 }