board/xes/xpedite550x/ddr.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright 2010 Extreme Engineering Solutions, Inc.
   4  * Copyright 2007-2008 Freescale Semiconductor, Inc.
   5  */
   6
   7 #include <common.h>
   8 #include <i2c.h>
   9
  10 #include <fsl_ddr_sdram.h>
  11 #include <fsl_ddr_dimm_params.h>
  12
  13 void get_spd(ddr3_spd_eeprom_t *spd, u8 i2c_address)
  14 {
  15         i2c_read(i2c_address, SPD_EEPROM_OFFSET, 2, (uchar *)spd,
  16                  sizeof(ddr3_spd_eeprom_t));
  17 }
  18
  19 /*
  20  *     There are traditionally three board-specific SDRAM timing parameters
  21  *     which must be calculated based on the particular PCB artwork.  These are:
  22  *     1.) CPO (Read Capture Delay)
  23  *             - TIMING_CFG_2 register
  24  *             Source: Calculation based on board trace lengths and
  25  *                     chip-specific internal delays.
  26  *     2.) CLK_ADJUST (Clock and Addr/Cmd alignment control)
  27  *             - DDR_SDRAM_CLK_CNTL register
  28  *             Source: Signal Integrity Simulations
  29  *     3.) 2T Timing on Addr/Ctl
  30  *             - TIMING_CFG_2 register
  31  *             Source: Signal Integrity Simulations
  32  *             Usually only needed with heavy load/very high speed (>DDR2-800)
  33  *
  34  *     ====== XPedite550x DDR3-800 read delay calculations ======
  35  *
  36  *     The P2020 processor provides an autoleveling option. Setting CPO to
  37  *     0x1f enables this auto configuration.
  38  */
  39
  40 typedef struct {
  41         unsigned short datarate_mhz_low;
  42         unsigned short datarate_mhz_high;
  43         unsigned char clk_adjust;
  44         unsigned char cpo;
  45 } board_specific_parameters_t;
  46
  47 const board_specific_parameters_t board_specific_parameters[][20] = {
  48         {
  49                 /* Controller 0 */
  50                 {
  51                         /* DDR3-600/667 */
  52                         .datarate_mhz_low       = 500,
  53                         .datarate_mhz_high      = 750,
  54                         .clk_adjust             = 5,
  55                         .cpo                    = 31,
  56                 },
  57                 {
  58                         /* DDR3-800 */
  59                         .datarate_mhz_low       = 750,
  60                         .datarate_mhz_high      = 850,
  61                         .clk_adjust             = 5,
  62                         .cpo                    = 31,
  63                 },
  64         },
  65 };
  66
  67 void fsl_ddr_board_options(memctl_options_t *popts,
  68                                 dimm_params_t *pdimm,
  69                                 unsigned int ctrl_num)
  70 {
  71         const board_specific_parameters_t *pbsp =
  72                                 &(board_specific_parameters[ctrl_num][0]);
  73         u32 num_params = sizeof(board_specific_parameters[ctrl_num]) /
  74                                 sizeof(board_specific_parameters[0][0]);
  75         u32 i;
  76         ulong ddr_freq;
  77
  78         /*
  79          * Set odt_rd_cfg and odt_wr_cfg. If the there is only one dimm in
  80          * that controller, set odt_wr_cfg to 4 for CS0, and 0 to CS1. If
  81          * there are two dimms in the controller, set odt_rd_cfg to 3 and
  82          * odt_wr_cfg to 3 for the even CS, 0 for the odd CS.
  83          */
  84         for (i = 0; i < CONFIG_CHIP_SELECTS_PER_CTRL; i++) {
  85                 if (i&1) {      /* odd CS */
  86                         popts->cs_local_opts[i].odt_rd_cfg = 0;
  87                         popts->cs_local_opts[i].odt_wr_cfg = 0;
  88                 } else {        /* even CS */
  89                         if (CONFIG_DIMM_SLOTS_PER_CTLR == 1) {
  90                                 popts->cs_local_opts[i].odt_rd_cfg = 0;
  91                                 popts->cs_local_opts[i].odt_wr_cfg = 4;
  92                         } else if (CONFIG_DIMM_SLOTS_PER_CTLR == 2) {
  93                                 popts->cs_local_opts[i].odt_rd_cfg = 3;
  94                                 popts->cs_local_opts[i].odt_wr_cfg = 3;
  95                         }
  96                 }
  97         }
  98
  99         /*
 100          * Get clk_adjust, cpo, write_data_delay,2T, according to the board ddr
 101          * freqency and n_banks specified in board_specific_parameters table.
 102          */
 103         ddr_freq = get_ddr_freq(0) / 1000000;
 104
 105         for (i = 0; i < num_params; i++) {
 106                 if (ddr_freq >= pbsp->datarate_mhz_low &&
 107                     ddr_freq <= pbsp->datarate_mhz_high) {
 108                         popts->clk_adjust = pbsp->clk_adjust;
 109                         popts->cpo_override = pbsp->cpo;
 110                         popts->twot_en = 0;
 111                         break;
 112                 }
 113                 pbsp++;
 114         }
 115
 116         if (i == num_params) {
 117                 printf("Warning: board specific timing not found "
 118                 "for data rate %lu MT/s!\n", ddr_freq);
 119         }
 120
 121         /*
 122          * Factors to consider for half-strength driver enable:
 123          *      - number of DIMMs installed
 124          */
 125         popts->half_strength_driver_enable = 0;
 126
 127         /*
 128          * Enable on-die termination.
 129          * From the Micron Technical Node TN-41-04, RTT_Nom should typically
 130          * be 30 to 40 ohms, while RTT_WR should be 120 ohms.  Setting RTT_WR
 131          * is handled in the Freescale DDR3 driver.  Set RTT_Nom here.
 132          */
 133         popts->rtt_override = 1;
 134         popts->rtt_override_value = 3;
 135 }