design/sys/iop/niu/rtl/niu_dmc_dmaarb.v

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// OpenSPARC T2 Processor File: niu_dmc_dmaarb.v
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`include "txc_defines.h"
`include "niu_dmc_reg_defines.h"

module niu_dmc_dmaarb (/*AUTOARG*/
   // Outputs
   ArbDone, DMANum, DMAsGranted,
   // Inputs
   SysClk, Reset_L, Choose_DMAs, DMA_Reqs
   );


   input SysClk;
   input Reset_L;
   input Choose_DMAs;
   input [31:0] DMA_Reqs;

   output ArbDone;
   output [4:0] DMANum;
   output [31:0] DMAsGranted;


   reg [31:0]     DMAsGranted;
   reg [31:0]     Select_DMA_Grant;
   reg [3:0]      DMA_Request_ArbState;
   reg            ArbDone;
   reg [4:0]      DMANum;


   parameter DMA_REQ_ARB_IDLE   = 4'h0,
             SELECT_DMA_NUM = 4'h1,
             DMA_REQ_ARB_DONE = 4'h2;

  //VCS coverage off
  // synopsys translate_off
   reg [192:1]    CACHE_REQ_ARB_STATE;

     always @(DMA_Request_ArbState)
     begin
        case(DMA_Request_ArbState)
          DMA_REQ_ARB_IDLE :            CACHE_REQ_ARB_STATE = "DMA_REQ_ARB_IDLE";
          SELECT_DMA_NUM:    CACHE_REQ_ARB_STATE = "SELECT_DMA_NUM";
          DMA_REQ_ARB_DONE :   CACHE_REQ_ARB_STATE = "DMA_REQ_ARB_DONE";
          default :            CACHE_REQ_ARB_STATE = "UNKNOWN";
        endcase
     end
   // synopsys translate_on
   //VCS coverage on


  always@(posedge SysClk ) begin
     if(!Reset_L)begin
        DMA_Request_ArbState <= DMA_REQ_ARB_IDLE;
        DMAsGranted <= 32'h0;
        Select_DMA_Grant <= 32'h0;
        ArbDone <= 1'b1;
        DMANum<= 5'h0;
     end else
       begin
         case(DMA_Request_ArbState) // synopsys parallel_case
           DMA_REQ_ARB_IDLE: begin
              ArbDone <=1'b0;
              if(Choose_DMAs) begin
                 Select_DMA_Grant <= DMA_Reqs & ~DMAsGranted;
                 DMA_Request_ArbState <= SELECT_DMA_NUM;
              end else begin // if (choose_available_dmas)
                 DMAsGranted <= 32'h0;
                 Select_DMA_Grant <= 32'h0;
              end // else: !if(choose_available_dmas)
           end // case: DMA_REQ_ARB_IDLE
           SELECT_DMA_NUM: begin
              ArbDone <=1'b1;
              casex(Select_DMA_Grant) // Synopsys full_case
                32'b0000_0000_0000_0000_0000_0000_0000_0001: begin
                   DMAsGranted <= 32'b0000_0000_0000_0000_0000_0000_0000_0001;
                   DMANum<= `DMA_CHANNEL_ZERO;
                end // case: 32'b0000_0000_0000_0000_0000_0000_0000_0001
                32'b????_????_????_????_????_????_????_??1?:  begin
                   DMAsGranted <= 32'b0000_0000_0000_0000_0000_0000_0000_0010;
                   DMANum<= `DMA_CHANNEL_ONE;
                end
                32'b????_????_????_????_????_????_????_?10?: begin
                   DMAsGranted <= 32'b0000_0000_0000_0000_0000_0000_0000_0100;
                   DMANum<= `DMA_CHANNEL_TWO;
                  end
                32'b????_????_????_????_????_????_????_100?:  begin
                   DMAsGranted <= 32'b0000_0000_0000_0000_0000_0000_0000_1000;
                   DMANum<= `DMA_CHANNEL_THREE;
                end
                32'b????_????_????_????_????_????_???1_000?:  begin
                   DMAsGranted <= 32'b0000_0000_0000_0000_0000_0000_0001_0000;
                   DMANum<= `DMA_CHANNEL_FOUR;
                end
                32'b????_????_????_????_????_????_??10_000?:  begin
                   DMAsGranted <= 32'b0000_0000_0000_0000_0000_0000_0010_0000;
                   DMANum<= `DMA_CHANNEL_FIVE;
                end
                32'b????_????_????_????_????_????_?100_000?:  begin
                   DMAsGranted <= 32'b0000_0000_0000_0000_0000_0000_0100_0000;
                   DMANum<= `DMA_CHANNEL_SIX;

                end
                32'b????_????_????_????_????_????_1000_000?:  begin
                   DMAsGranted <= 32'b0000_0000_0000_0000_0000_0000_1000_0000;
                   DMANum<= `DMA_CHANNEL_SEVEN;
                end
                32'b????_????_????_????_????_???1_0000_000?:  begin
                   DMAsGranted <= 32'b0000_0000_0000_0000_0000_0001_0000_0000;
                   DMANum<= `DMA_CHANNEL_EIGHT;
                end
                32'b????_????_????_????_????_??10_0000_000?:  begin
                   DMAsGranted <= 32'b0000_0000_0000_0000_0000_0010_0000_0000;
                   DMANum<= `DMA_CHANNEL_NINE;
                end
                32'b????_????_????_????_????_?100_0000_000?:  begin
                   DMAsGranted <= 32'b0000_0000_0000_0000_0000_0100_0000_0000;
                   DMANum<= `DMA_CHANNEL_TEN;
                end
                32'b????_????_????_????_????_1000_0000_000?:  begin
                   DMAsGranted <= 32'b0000_0000_0000_0000_0000_1000_0000_0000;
                   DMANum<= `DMA_CHANNEL_ELEVEN;
                end
                32'b????_????_????_????_???1_0000_0000_000?:  begin
                   DMAsGranted <= 32'b0000_0000_0000_0000_0001_0000_0000_0000;
                   DMANum<= `DMA_CHANNEL_TWELVE;
                end
                32'b????_????_????_????_??10_0000_0000_000?:  begin
                   DMAsGranted <= 32'b0000_0000_0000_0000_0010_0000_0000_0000;
                   DMANum<= `DMA_CHANNEL_THIRTEEN;
                end
                32'b????_????_????_????_?100_0000_0000_000?:  begin
                   DMAsGranted <= 32'b0000_0000_0000_0000_0100_0000_0000_0000;
                   DMANum<= `DMA_CHANNEL_FOURTEEN;
                end
                32'b????_????_????_????_1000_0000_0000_000?:  begin
                   DMAsGranted <= 32'b0000_0000_0000_0000_1000_0000_0000_0000;
                   DMANum<= `DMA_CHANNEL_FIFTEEN;
                end
                32'b????_????_????_???1_0000_0000_0000_000?:  begin
                   DMAsGranted <= 32'b0000_0000_0000_0001_0000_0000_0000_0000;
                   DMANum<= `DMA_CHANNEL_SIXTEEN;
                end
                32'b????_????_????_??10_0000_0000_0000_000?:  begin
                   DMAsGranted <= 32'b0000_0000_0000_0010_0000_0000_0000_0000;
                   DMANum<= `DMA_CHANNEL_SEVENTEEN;
                end
                32'b????_????_????_?100_0000_0000_0000_000?:  begin
                   DMAsGranted <= 32'b0000_0000_0000_0100_0000_0000_0000_0000;
                   DMANum<= `DMA_CHANNEL_EIGHTEEN;
                end
                32'b????_????_????_1000_0000_0000_0000_000?:  begin
                   DMAsGranted <= 32'b0000_0000_0000_1000_0000_0000_0000_0000;
                   DMANum<= `DMA_CHANNEL_NINETEEN;
                end
                32'b????_????_???1_0000_0000_0000_0000_000?:  begin
                   DMAsGranted <= 32'b0000_0000_0001_0000_0000_0000_0000_0000;
                   DMANum<= `DMA_CHANNEL_TWENTY;
                end
                32'b????_????_??10_0000_0000_0000_0000_000?:  begin
                   DMAsGranted <= 32'b0000_0000_0010_0000_0000_0000_0000_0000;
                   DMANum<= `DMA_CHANNEL_TWENTYONE;
                end
                32'b????_????_?100_0000_0000_0000_0000_000?:  begin
                   DMAsGranted <= 32'b0000_0000_0100_0000_0000_0000_0000_0000;
                   DMANum<= `DMA_CHANNEL_TWENTYTWO;
                end
                32'b????_????_1000_0000_0000_0000_0000_000?:  begin
                   DMAsGranted <= 32'b0000_0000_1000_0000_0000_0000_0000_0000;
                   DMANum<= `DMA_CHANNEL_TWENTYTHREE;
                end
                default:   begin
                   DMAsGranted <= 32'b0;
                   DMANum<=`DMA_CHANNEL_ZERO;
                end

              endcase // case(DMA_Request_ArbState)
              DMA_Request_ArbState <= DMA_REQ_ARB_DONE;
           end // case: SELECT_DMA_NUM
           DMA_REQ_ARB_DONE: begin
              DMA_Request_ArbState <= DMA_REQ_ARB_IDLE;
              ArbDone <=1'b0;
           end // case: DMA_REQ_ARB_DONE
         endcase // case(DMA_Request_ArbState)
       end // else: !if(!Reset_L)
  end // always@ (posedge SysClk )
endmodule // niu_dmc_dmaarb