board/freescale/mpc8536ds/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 get_spd(ddr2_spd_eeprom_t *spd, unsigned char i2c_address)
  16 {
  17         i2c_read(i2c_address, 0, 1, (uchar *)spd, sizeof(ddr2_spd_eeprom_t));
  18 }
  19
  20 void fsl_ddr_get_spd(ddr2_spd_eeprom_t *ctrl_dimms_spd,
  21                       unsigned int ctrl_num)
  22 {
  23         unsigned int i;
  24
  25         if (ctrl_num) {
  26                 printf("%s unexpected ctrl_num = %u\n", __FUNCTION__, ctrl_num);
  27                 return;
  28         }
  29
  30         for (i = 0; i < CONFIG_DIMM_SLOTS_PER_CTLR; i++) {
  31                 get_spd(&(ctrl_dimms_spd[i]), SPD_EEPROM_ADDRESS);
  32         }
  33 }
  34
  35 void fsl_ddr_board_options(memctl_options_t *popts,
  36                                 dimm_params_t *pdimm,
  37                                 unsigned int ctrl_num)
  38 {
  39         /*
  40          * Factors to consider for clock adjust:
  41          *      - number of chips on bus
  42          *      - position of slot
  43          *      - DDR1 vs. DDR2?
  44          *      - ???
  45          *
  46          * This needs to be determined on a board-by-board basis.
  47          *      0110    3/4 cycle late
  48          *      0111    7/8 cycle late
  49          */
  50         popts->clk_adjust = 7;
  51
  52         /*
  53          * Factors to consider for CPO:
  54          *      - frequency
  55          *      - ddr1 vs. ddr2
  56          */
  57         popts->cpo_override = 10;
  58
  59         /*
  60          * Factors to consider for write data delay:
  61          *      - number of DIMMs
  62          *
  63          * 1 = 1/4 clock delay
  64          * 2 = 1/2 clock delay
  65          * 3 = 3/4 clock delay
  66          * 4 = 1   clock delay
  67          * 5 = 5/4 clock delay
  68          * 6 = 3/2 clock delay
  69          */
  70         popts->write_data_delay = 3;
  71
  72         /*
  73          * Factors to consider for half-strength driver enable:
  74          *      - number of DIMMs installed
  75          */
  76         popts->half_strength_driver_enable = 0;
  77
  78         /*
  79          * For wake up arp feature, we need enable auto self refresh
  80          */
  81         popts->auto_self_refresh_en = 1;
  82         popts->sr_it = 0x6;
  83 }