design/sys/iop/dmu/rtl/dmu_ilu_iil_rcdbldr.v

// ========== Copyright Header Begin ==========================================
//
// OpenSPARC T2 Processor File: dmu_ilu_iil_rcdbldr.v
// Copyright (C) 1995-2007 Sun Microsystems, Inc. All Rights Reserved
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module dmu_ilu_iil_rcdbldr (
                                 clk,
                                 rst_l,

                                 p2d_ihb_data,
                                 y2k_rcd,

                                 iil2isb_tag,
                                 isb2iil_low_addr,

                                 ihb_rcd_is_cpl,
                                 credit_type,

                                 is_ihb_rcd,
                                 is_cto_rcd,
                                 pio_tag_gen,

                                 in_ihb_rcd);

  // >>>>>>>>>>>>>>>>>>>>>>>>> Parameter Declarations <<<<<<<<<<<<<<<<<<<<<<<<<

  // rcd type
  parameter   DMA_MRD     = 7'b0z00000,
              DMA_MRDLK   = 7'b0z00001,
              DMA_MWR     = 7'b1z00000,
              DMA_IORD    = 7'b0000010,
              DMA_IOWR    = 7'b1000010,
              DMA_CFGRD   = 7'b000010z,
              DMA_CFGWR   = 7'b100010z,
              DMA_MSG     = 7'b0110zzz,
              PIO_CPL     = 7'b0001010,
              PIO_CPLD    = 7'b1001010;

  // >>>>>>>>>>>>>>>>>>>>>>>>> Port Declarations <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

  //---------------------------------------------------------------------
  //  Clock and Reset Signals
  //---------------------------------------------------------------------
  input           clk;              // input clock
  input           rst_l;            // synchronous reset

  //---------------------------------------------------------------------
  //   IHB and IHB management interface
  //---------------------------------------------------------------------
  input  [`FIRE_IHB_REC_WDTH-1:0]  p2d_ihb_data;     // TLP header record

  //---------------------------------------------------------------------
  //   record interface to TMU
  //---------------------------------------------------------------------
  output [`FIRE_DLC_IPE_REC_WDTH-1:0]  y2k_rcd;      // ingress PEC record

  //---------------------------------------------------------------------
  //   sub-block to sub-block interface
  //---------------------------------------------------------------------
  output [4:0]    iil2isb_tag;
  input [3:2]     isb2iil_low_addr;

  //---------------------------------------------------------------------
  //   type decoder outputs
  //---------------------------------------------------------------------
  output          ihb_rcd_is_cpl;      //                             to *_xfrfsm.v
  output [1:0]    credit_type;         // header type,                to *_crdtcnt.v

  //---------------------------------------------------------------------
  //   info from *_xfrfsm.v
  //---------------------------------------------------------------------
  input           is_ihb_rcd;          // in-process rcd a ihb rcd,  from *_xfrfsm.v
  input           is_cto_rcd;          // in-process rcd a CTO rcd,  from *_xfrfsm.v
  input [4:0]     pio_tag_gen;         // pio_tag for cpl generator, from *_xfrfsm.v

  //---------------------------------------------------------------------
  //   talk to parchk
  //---------------------------------------------------------------------
  output [`FIRE_IHB_REC_WDTH-1:0] in_ihb_rcd;

  // >>>>>>>>>>>>>>>>>>>>>>>>> Data Type Declarations <<<<<<<<<<<<<<<<<<<<<<<<<

  // ~~~~~~~~~~~~~~~~~~~~~~~~~ REGISTER - FLOPS ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  reg [`FIRE_IHB_REC_WDTH-1:0]      in_ihb_rcd;
  reg [`FIRE_DLC_IPE_REC_WDTH-1:0]  y2k_rcd;

  // ~~~~~~~~~~~~~~~~~~~~~~~~~ REGISTER - NON-FLOPS ~~~~~~~~~~~~~~~~~~~~~~~~
  reg                               ihb_rcd_is_cpl;
  reg                               is_unsupported_req;
  reg [1:0]                         credit_type;

  // ~~~~~~~~~~~~~~~~~~~~~~~~~ NETS ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  wire [`FIRE_DLC_IPE_REC_WDTH-1:0]     n_y2k_rcd;

  //---------------------------------------------------------------------
  // In record (IHB) fields
  //---------------------------------------------------------------------
  wire [`FIRE_IHB_2DWH_WDTH-1:0]        in_rcd_2dwh;
  wire [`FIRE_IHB_3DWH_WDTH-1:0]        in_rcd_3dwh;
  wire [`FIRE_IHB_4DWH_WDTH-1:2]        in_rcd_4dwh;  // strip off 2-LSB

  //---------------------------------------------------------------------
  // Out record (ingress PEC) fields
  //---------------------------------------------------------------------
  wire [`FIRE_DLC_IPE_ADDR_WDTH-1:30]   out_rcd_addr_hi; // shared

  wire [29:0]                           out_ihb_rcd_addr_lo; // to be muxed

  wire [`FIRE_DLC_IPE_LEN_WDTH-1:0]     out_rcd_len; // shared
  wire [`FIRE_DLC_IPE_ATR_WDTH-1:0]     out_rcd_atr; // shared
  wire [`FIRE_DLC_IPE_TC_WDTH-1:0]      out_rcd_tc; // shared

  wire [`FIRE_DLC_IPE_TYPE_WDTH-1:0]    out_ihb_rcd_type; // to be muxed
  wire [`FIRE_DLC_IPE_F_WDTH-1:0]       out_ihb_rcd_f; // to be muxed
  wire [2:0]                            out_ihb_cpl_status; // to be muxed

  wire [5:2]                            align_addr;

  //---------------------------------------------------------------------
  // new generated PIO cpl rcd
  //---------------------------------------------------------------------
  wire [2:0]                            gen_cpl_rcd_status;
  wire [29:0]                           gen_cpl_rcd_addr_lo;

  //---------------------------------------------------------------------
  // type decoder
  //---------------------------------------------------------------------
  wire [6:0]                            in_rcd_type;
  wire [2:0]                            in_rcd_cpl_status;
  wire [4:0]                            in_rcd_pio_tag;

  wire                                  is_successful_pio_cpl;

  // >>>>>>>>>>>>>>>>>>>>>>>>> Zero In Checkers <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

  // 0in known_driven -var is_ihb_rcd
  // 0in known_driven -var is_cto_rcd
  // 0in bits_on -var credit_type -max 1 -active is_ihb_rcd -message "illegal credit_type"
  // 0in bits_on -var {ihb_rcd_is_cpl, is_unsupported_req} -max 1 -active is_ihb_rcd

  // >>>>>>>>>>>>>>>>>>>>>>>>> RTL/Behavioral Model <<<<<<<<<<<<<<<<<<<<<<<<<<<

  //---------------------------------------------------------------------
  // In record fields
  //---------------------------------------------------------------------
  assign in_rcd_2dwh = in_ihb_rcd[`FIRE_IHB_2DWH_MSB:`FIRE_IHB_2DWH_LSB];
  assign in_rcd_3dwh = in_ihb_rcd[`FIRE_IHB_3DWH_MSB:`FIRE_IHB_3DWH_LSB];
  assign in_rcd_4dwh = in_ihb_rcd[`FIRE_IHB_4DWH_MSB:`FIRE_IHB_4DWH_LSB+2];

  //---------------------------------------------------------------------
  // type decoder
  //---------------------------------------------------------------------

  assign in_rcd_type = in_ihb_rcd[`FIRE_IHB_1DWH_MSB-1:`FIRE_IHB_1DWH_MSB-7];

  assign in_rcd_cpl_status = in_rcd_2dwh[15:13];
  assign in_rcd_pio_tag = in_rcd_3dwh[12:8];
  assign is_successful_pio_cpl = ~(|in_rcd_cpl_status);
  assign iil2isb_tag = is_ihb_rcd ? in_rcd_pio_tag : pio_tag_gen;

  always @ (in_rcd_type)
    begin
      ihb_rcd_is_cpl = 1'b0;
      is_unsupported_req = 1'b0;
      credit_type = 2'b0;

      casez (in_rcd_type) // 0in < case -parallel -full -active is_ihb_rcd
        DMA_MRD,
        DMA_MRDLK: credit_type = 2'b10;

        DMA_MWR,
        DMA_MSG: credit_type = 2'b01;

        DMA_IORD,
        DMA_CFGRD,
        DMA_IOWR,
        DMA_CFGWR:
          begin
            is_unsupported_req = 1'b1;
            credit_type = 2'b10;
          end

        PIO_CPL,
        PIO_CPLD:
          begin
            ihb_rcd_is_cpl = 1'b1;
          end
      endcase // casez(in_rcd_type)
    end


  //---------------------------------------------------------------------
  // new rcd fields based on IHB rcd
  //---------------------------------------------------------------------

  assign out_ihb_rcd_f = is_unsupported_req ?
                           2'b00 : in_rcd_type[6:5];
  assign out_ihb_rcd_type = is_unsupported_req ? 5'b01001 : in_rcd_type[4:0];

  assign out_rcd_tc = in_ihb_rcd[`FIRE_IHB_1DWH_LSB+22:`FIRE_IHB_1DWH_LSB+20];

  assign out_rcd_atr = in_ihb_rcd[`FIRE_IHB_1DWH_LSB+13:`FIRE_IHB_1DWH_LSB+12];
  assign out_rcd_len = in_ihb_rcd[`FIRE_IHB_1DWH_LSB+9:`FIRE_IHB_1DWH_LSB];

  assign out_rcd_addr_hi = in_rcd_type[5] ? in_rcd_3dwh : 32'b0;

  assign align_addr = ihb_rcd_is_cpl ? {2'b0, isb2iil_low_addr[3:2]} : in_rcd_3dwh[5:2];

  assign out_ihb_rcd_addr_lo = in_rcd_type[5] ? in_rcd_4dwh :
                                               {in_rcd_3dwh[31:6], align_addr};

  // --------------------------------------------------------------------------
  // According to the PCI-Express spec, all reserved status values
  // (i.e. 011, 101, 110, and 111) must be treated as "Unsupported Request".
  // Moreover, CLU maps the two unreserved status (unsupported request and
  // completer abort) to JBUS bus error. Therefore, ILU traps PIO Cpl with
  // configuration retry status (TLU takes care of it); converts PIO Cpl with
  // status other that succesful to unsupported request status
  // --------------------------------------------------------------------------
  assign out_ihb_cpl_status = is_successful_pio_cpl ? in_rcd_cpl_status : 3'b001;

  //---------------------------------------------------------------------
  // IIL sourced PIO Cpl rcd fields  - new generated PIO cpl rcd, status is
  //       "UR" (3'b001) if it is in drain state,
  //       "TO" (3'b111 FIRE internal value) if it serves a CTO request from TLU
  //---------------------------------------------------------------------
  assign gen_cpl_rcd_status = is_cto_rcd ? 3'b111 : 3'b001;

  assign gen_cpl_rcd_addr_lo = {{`FIRE_DLC_IPE_REQID_WDTH{1'b0}},
                                {3'b0, pio_tag_gen},
                                pio_tag_gen, pio_tag_gen[0]};
  // pio_tag_gen is used to fill rsv fields on the last line above

  //---------------------------------------------------------------------
  // n_y2k_rcd
  //---------------------------------------------------------------------
  assign n_y2k_rcd = {(is_ihb_rcd ? {out_ihb_rcd_f, out_ihb_rcd_type} : 7'b0001010),
                      out_rcd_tc,
                      out_rcd_atr,
                      out_rcd_len,
                      in_rcd_2dwh[31:16], // req_id
                      (is_ihb_rcd ? (ihb_rcd_is_cpl ? out_ihb_cpl_status :
                                     in_rcd_2dwh[15:13]) :
                       gen_cpl_rcd_status),
                      in_rcd_2dwh[12:0],
                      out_rcd_addr_hi,
                      (is_ihb_rcd ? out_ihb_rcd_addr_lo : gen_cpl_rcd_addr_lo) };

  always @ (posedge clk)
        if(~rst_l) begin
      in_ihb_rcd <= {`FIRE_IHB_REC_WDTH{1'b0}};
      y2k_rcd <= {`FIRE_DLC_IPE_REC_WDTH{1'b0}};
   end
    else begin
      in_ihb_rcd <= p2d_ihb_data;
      y2k_rcd <= n_y2k_rcd;
    end

  // >>>>>>>>>>>>>>>>>>>>>>>>> Instantiations <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<

endmodule // dmu_ilu_iil_rcdbldr