ctrl.v

DDR2源代码 DDR2源代码 DDR2源代码

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//*****************************************************************************
//   ____  ____
//  /   /\/   /
// /___/  \  /    Vendor: Xilinx
// \   \   \/     Version: 2.1
//  \   \         Application: MIG
//  /   /         Filename: ctrl.v
// /___/   /\     Date Last Modified: $Date: 2008/01/09 15:43:36 $
// \   \  /  \    Date Created: Wed Aug 30 2006
//  \___\/\___\
//
//
//Device: Virtex-5
//Design Name: DDR/DDR2
//Purpose:
//   This module is the main control logic of the memory interface. All
//   commands are issued from here according to the burst, CAS Latency and the
//   user commands.
//Reference:
//Revision History:
// Rev1.2 - Fixed auto refresh to activate bug. KP 11-19-2007
//*****************************************************************************

`timescale 1ns/1ps

module ctrl #
  (
   // Following parameters are for 72-bit RDIMM design (for ML561 Reference 
   // board design). Actual values may be different. Actual parameters values 
   // are passed from design top module ddr2_sdram module. Please refer to
   // the ddr2_sdram module for actual values.
   parameter BANK_WIDTH    = 2,
   parameter COL_WIDTH     = 10,
   parameter CS_BITS       = 0,
   parameter CS_NUM        = 1,
   parameter ROW_WIDTH     = 14,
   parameter ADDITIVE_LAT  = 0,
   parameter BURST_LEN     = 4,
   parameter CAS_LAT       = 5,
   parameter ECC_ENABLE    = 0,
   parameter REG_ENABLE    = 1,
   parameter TREFI_NS      = 7800,
   parameter TRAS          = 40000,
   parameter TRCD          = 15000,
   parameter TRRD          = 10000,
   parameter TRFC          = 105000,
   parameter TRP           = 15000,
   parameter TRTP          = 7500,
   parameter TWR           = 15000,
   parameter TWTR          = 10000,
   parameter CLK_PERIOD    = 3000,
   parameter MULTI_BANK_EN = 1,
   parameter TWO_T_TIME_EN = 0,
   parameter DDR_TYPE      = 1
   )
  (
   input                   clk,
   input                   rst,
   input [2:0]             af_cmd,
   input [30:0]            af_addr,
   input                   af_empty,
   input                   phy_init_done,
   output                  ctrl_ref_flag,
   output                  ctrl_af_rden,
   output reg              ctrl_wren,
   output reg              ctrl_rden,
   output [ROW_WIDTH-1:0]  ctrl_addr,
   output [BANK_WIDTH-1:0] ctrl_ba,
   output                  ctrl_ras_n,
   output                  ctrl_cas_n,
   output                  ctrl_we_n,
   output [CS_NUM-1:0]     ctrl_cs_n
   );

  // input address split into various ranges
  localparam ROW_RANGE_START     = COL_WIDTH;
  localparam ROW_RANGE_END       = ROW_WIDTH + ROW_RANGE_START - 1;
  localparam BANK_RANGE_START    = ROW_RANGE_END + 1;
  localparam BANK_RANGE_END      = BANK_WIDTH + BANK_RANGE_START - 1;
  localparam CS_RANGE_START      = BANK_RANGE_START + BANK_WIDTH;
  localparam CS_RANGE_END        = CS_NUM + CS_RANGE_START - 1;
  // compare address (for determining bank/row hits) split into various ranges
  // (compare address doesn't include column bits)
  localparam CMP_WIDTH            = CS_NUM + BANK_WIDTH + ROW_WIDTH;
  localparam CMP_ROW_RANGE_START  = 0;
  localparam CMP_ROW_RANGE_END    = ROW_WIDTH + CMP_ROW_RANGE_START - 1;
  localparam CMP_BANK_RANGE_START = CMP_ROW_RANGE_END + 1;
  localparam CMP_BANK_RANGE_END   = BANK_WIDTH + CMP_BANK_RANGE_START - 1;
  localparam CMP_CS_RANGE_START   = CMP_BANK_RANGE_END + 1;
  localparam CMP_CS_RANGE_END     = CS_BITS + CMP_CS_RANGE_START;

  localparam BURST_LEN_DIV2      = BURST_LEN / 2;
  localparam OPEN_BANK_NUM       = 4;
  localparam CS_BITS_FIX         = (CS_BITS == 0) ? 1 : CS_BITS;

  // calculation counters based on clock cycle and memory parameters
  // TRAS: ACTIVE->PRECHARGE interval - 2
  localparam integer TRAS_CYC = (TRAS + CLK_PERIOD)/CLK_PERIOD;
  // TRCD: ACTIVE->READ/WRITE interval - 3 (for DDR2 factor in ADD_LAT)
  localparam integer TRRD_CYC = (TRRD + CLK_PERIOD)/CLK_PERIOD;
  localparam integer TRCD_CYC = (((TRCD + CLK_PERIOD)/CLK_PERIOD) >
                                 ADDITIVE_LAT )?
             ((TRCD+CLK_PERIOD)/ CLK_PERIOD) - ADDITIVE_LAT : 0;
  // TRFC: REFRESH->REFRESH, REFRESH->ACTIVE interval - 2
  localparam integer TRFC_CYC = (TRFC + CLK_PERIOD)/CLK_PERIOD;
  // TRP: PRECHARGE->COMMAND interval - 2
   // for precharge all add 1 extra clock cycle
  localparam integer TRP_CYC =  ((TRP + CLK_PERIOD)/CLK_PERIOD) +1;
  // TRTP: READ->PRECHARGE interval - 2 (Al + BL/2 + (max (TRTP, 2tck))-2
  localparam integer TRTP_TMP_MIN = (((TRTP + CLK_PERIOD)/CLK_PERIOD) >= 2)?
                                     ((TRTP + CLK_PERIOD)/CLK_PERIOD) : 2;
  localparam integer TRTP_CYC = TRTP_TMP_MIN + ADDITIVE_LAT
                                + BURST_LEN_DIV2 - 2;
  // TWR: WRITE->PRECHARGE interval - 2
  localparam integer WR_LAT = (DDR_TYPE > 0) ? CAS_LAT + ADDITIVE_LAT - 1 : 1;
  localparam integer TWR_CYC = ((TWR + CLK_PERIOD)/CLK_PERIOD) +
             WR_LAT + BURST_LEN_DIV2 ;
  // TWTR: WRITE->READ interval - 3 (for DDR1, TWTR = 2 clks)
  // DDR2 = CL-1 + BL/2 +TWTR
  localparam integer TWTR_TMP_MIN = (TWTR + CLK_PERIOD)/CLK_PERIOD;
  localparam integer TWTR_CYC = (DDR_TYPE > 0) ? (TWTR_TMP_MIN + (CAS_LAT -1)
                                 + BURST_LEN_DIV2 ): 2;

  //  TRTW: READ->WRITE interval - 3
  //  DDR1: CL + (BL/2)
  //  DDR2: (BL/2) + 2. Two more clocks are added to
  //  the DDR2 counter to account for the delay in
  //  arrival of the DQS during reads (pcb trace + buffer
  //  delays + memory parameters).
  localparam TRTW_CYC = (DDR_TYPE > 0) ? BURST_LEN_DIV2 + 4 :
             (CAS_LAT == 25) ? 2 + BURST_LEN_DIV2 : CAS_LAT + BURST_LEN_DIV2;

  localparam integer CAS_LAT_RD = (CAS_LAT == 25) ? 2 : CAS_LAT;

  // Make sure all values >= 0 (some may be = 0)
  localparam TRAS_COUNT = (TRAS_CYC > 0) ? TRAS_CYC : 0;
  localparam TRCD_COUNT = (TRCD_CYC > 0) ? TRCD_CYC : 0;
  localparam TRRD_COUNT = (TRRD_CYC > 0) ? TRRD_CYC : 0;
  localparam TRFC_COUNT = (TRFC_CYC > 0) ? TRFC_CYC : 0;
  localparam TRP_COUNT  = (TRP_CYC > 0)  ? TRP_CYC  : 0;
  localparam TRTP_COUNT = (TRTP_CYC > 0) ? TRTP_CYC : 0;
  localparam TWR_COUNT  = (TWR_CYC > 0)  ? TWR_CYC  : 0;
  localparam TWTR_COUNT = (TWTR_CYC > 0) ? TWTR_CYC : 0;
  localparam TRTW_COUNT = (TRTW_CYC > 0) ? TRTW_CYC : 0;

  // Auto refresh interval
  localparam TREFI_COUNT = ((TREFI_NS * 1000)/CLK_PERIOD) - 1;

  // memory controller states
  localparam   CTRL_IDLE                =     5'h00;
  localparam   CTRL_PRECHARGE           =     5'h01;
  localparam   CTRL_PRECHARGE_WAIT      =     5'h02;
  localparam   CTRL_AUTO_REFRESH        =     5'h03;
  localparam   CTRL_AUTO_REFRESH_WAIT   =     5'h04;
  localparam   CTRL_ACTIVE              =     5'h05;
  localparam   CTRL_ACTIVE_WAIT         =     5'h06;
  localparam   CTRL_BURST_READ          =     5'h07;
  localparam   CTRL_READ_WAIT           =     5'h08;
  localparam   CTRL_BURST_WRITE         =     5'h09;
  localparam   CTRL_WRITE_WAIT          =     5'h0A;
  localparam   CTRL_PRECHARGE_WAIT1     =     5'h0B;


  reg [CMP_WIDTH-1:0]                      act_addr_r;
  wire [30:0]                              af_addr_r;
  reg [30:0]                               af_addr_r1;
  reg [30:0]                               af_addr_r2;
  reg [30:0]                               af_addr_r3;
  wire [2:0]                               af_cmd_r;
  reg [2:0]                                af_cmd_r1;
  reg [2:0]                                af_cmd_r2;
  reg                                      af_valid_r;
  reg                                      af_valid_r1;
  reg                                      af_valid_r2;
  reg [CS_BITS_FIX :0]                     auto_cnt_r;
  reg                                      auto_ref_r;
  reg [(OPEN_BANK_NUM*CMP_WIDTH)-1:0]      bank_cmp_addr_r;
  reg [OPEN_BANK_NUM-1:0]                  bank_hit;
  reg [OPEN_BANK_NUM-1:0]                  bank_hit_r;
  reg [OPEN_BANK_NUM-1:0]                  bank_hit_r1;
  reg [OPEN_BANK_NUM-1:0]                  bank_valid_r;
  reg                                      bank_conflict_r;
  reg                                      conflict_resolved_r;
  reg                                      ctrl_af_rden_r;
  reg                                      conflict_detect_r;
  wire                                     conflict_detect;
  reg [ROW_WIDTH-1:0]                      ddr_addr_r;
  wire [ROW_WIDTH-1:0]                     ddr_addr_col;
  wire [ROW_WIDTH-1:0]                     ddr_addr_row;
  reg [BANK_WIDTH-1:0]                     ddr_ba_r;
  reg                                      ddr_cas_n_r;
  reg [CS_NUM-1:0]                         ddr_cs_n_r;
  reg                                      ddr_ras_n_r;
  reg                                      ddr_we_n_r;
  reg [4:0]                                next_state;
  reg                                      no_precharge_wait_r;
  reg                                      no_precharge_r;
  reg                                      no_precharge_r1;
  reg                                      phy_init_done_r;
  reg [4:0]                                precharge_ok_cnt_r;
  reg                                      precharge_ok_r;
  reg [4:0]                                ras_cnt_r;
  reg [3:0]                                rcd_cnt_r;
  reg                                      rcd_cnt_ok_r;
  reg [2:0]                                rdburst_cnt_r;
  reg                                      rdburst_ok_r;
  reg                                      rdburst_rden_ok_r;
  reg                                      rd_af_flag_r;
  wire                                     rd_flag;
  reg                                      rd_flag_r;
  reg [4:0]                                rd_to_wr_cnt_r;
  reg                                      rd_to_wr_ok_r;
  reg                                      ref_flag_r;
  reg [11:0]                               refi_cnt_r;
  reg                                      refi_cnt_ok_r;
  reg                                      rst_r
                                           /* synthesis syn_preserve = 1 */;
  reg                                      rst_r1
                                           /* synthesis syn_maxfan = 10 */;
  reg [7:0]                                rfc_cnt_r;
  reg                                      rfc_ok_r;
  reg [3:0]                                row_miss;
  reg [3:0]                                row_conflict_r;
  reg [3:0]                                rp_cnt_r;
  reg                                      rp_cnt_ok_r;
  reg [CMP_WIDTH-1:0]                      sb_open_add_r;
  reg [4:0]                                state_r;
  reg [4:0]                                state_r1;
  wire                                     sm_rden;
  reg                                      sm_rden_r;
  reg [2:0]                                trrd_cnt_r;
  reg                                      trrd_cnt_ok_r;
  reg [2:0]                                two_t_enable_r;
  reg [CS_NUM-1:0]                         two_t_enable_r1;
  reg [2:0]                                wrburst_cnt_r;
  reg                                      wrburst_ok_r;
  reg                                      wrburst_wren_ok_r;
  wire                                     wr_flag;
  reg                                      wr_flag_r;
  reg [4:0]                                wr_to_rd_cnt_r;
  reg                                      wr_to_rd_ok_r;

  // XST attributes for local reset "tree"
  // synthesis attribute shreg_extract of rst_r is "no";
  // synthesis attribute shreg_extract of rst_r1 is "no";
  // synthesis attribute equivalent_register_removal of rst_r is "no"

  //***************************************************************************

  // sm_rden is used to assert read enable to the address FIFO
  assign sm_rden = ((state_r == CTRL_BURST_WRITE) ||
                    (state_r == CTRL_BURST_READ)) ;

  // assert read flag to the adress FIFO
  assign ctrl_af_rden = sm_rden || rd_af_flag_r;

  // local reset "tree" for controller logic only. Create this to ease timing
  // on reset path. Prohibit equivalent register removal on RST_R to prevent
  // "sharing" with other local reset trees (caution: make sure global fanout
  // limit is set to large enough value, otherwise SLICES may be used for
  // fanout control on RST_R.
  always @(posedge clk) begin
    rst_r  <= rst;
    rst_r1 <= rst_r;
  end

  //*****************************************************************
  // interpret commands from Command/Address FIFO
  //*****************************************************************

  assign wr_flag = (af_valid_r2) ? ((af_cmd_r2 == 3'b000) ? 1'b1 : 1'b0): 1'b0;
  assign rd_flag = (af_valid_r2) ? ((af_cmd_r2 == 3'b001) ? 1'b1 : 1'b0): 1'b0;

  always @(posedge clk) begin
    rd_flag_r <= rd_flag;
    wr_flag_r <= wr_flag;
  end

  //////////////////////////////////////////////////
  // The data from the address FIFO is fetched and
  // stored in two register stages. The data will be
  // pulled out of the second register stage whenever
  // the state machine can handle new data from the
  // address FIFO.

  // This flag is asserted when there is no
  // cmd & address in the pipe. When there is
  // valid cmd & addr from the address FIFO the
  // af_valid signals will be asserted. This flag will
  // be set the cycle af_valid_r is de-asserted.
  always @(posedge clk) begin
    // for simulation purposes - to force CTRL_AF_RDEN low during reset
    if (rst_r1)
      rd_af_flag_r <= 1'd0;
    else if((ctrl_af_rden_r) ||
            (rd_af_flag_r && (af_valid_r || af_valid_r1)))
         rd_af_flag_r <= 1'd0;
    else if (~af_valid_r1 || ~af_valid_r)
         rd_af_flag_r <= 1'd1;

  end

  // First register stage for the cmd & add from the FIFO.
  // The af_valid_r signal gives the status of the data
  // in this stage. The af_valid_r will be asserted when there
  // is valid data. This register stage will be updated
  // 1. read to the FIFO and the FIFO not empty
  // 2. After write and read states
  // 3. The valid signal is not asserted in the last stage.
  always @(posedge clk) begin
    if (rst_r1)begin
      af_valid_r <= 1'd0;
    end else begin
      if (ctrl_af_rden_r || sm_rden_r || ~af_valid_r1
          || ~af_valid_r2)begin
        af_valid_r <= ctrl_af_rden_r;
      end
    end
  end

  // The output register in the FIFO is used. The addr
  // and command are already registered in the FIFO.
  assign af_addr_r = af_addr;
  assign af_cmd_r = af_cmd;

  // Second register stage for the cmd & add from the FIFO.
  // The af_valid_r1 signal gives the status of the data
  // in this stage. The af_valid_r will be asserted when there
  // is valid data. This register stage will be updated
  // 1. read to the FIFO and the FIFO not empty and there
  // is no valid data on this stage
  // 2. After write and read states
  // 3. The valid signal is not asserted in the last stage.
  always@(posedge clk) begin
    if (rst_r1)begin
      af_valid_r1 <= 1'd0;
      af_addr_r1 <= {31{1'bx}};
      af_cmd_r1 <= {3{1'bx}};
    end else if (~af_valid_r1 || sm_rden_r ||
                  ~af_valid_r2) begin
      af_valid_r1 <= af_valid_r;
      af_addr_r1 <= af_addr_r;
      af_cmd_r1 <= af_cmd_r;
    end
  end

  // The state machine uses the address and command in this