Mercurial > pygar

     1 // The MIT License

     2 

     3 // Copyright (c) 2009 Massachusetts Institute of Technology

     4 

     5 // Permission is hereby granted, free of charge, to any person obtaining a copy

     6 // of this software and associated documentation files (the "Software"), to deal

     7 // in the Software without restriction, including without limitation the rights

     8 // to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

     9 // copies of the Software, and to permit persons to whom the Software is

    10 // furnished to do so, subject to the following conditions:

    11 

    12 // The above copyright notice and this permission notice shall be included in

    13 // all copies or substantial portions of the Software.

    14 

    15 // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

    16 // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

    17 // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

    18 // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

    19 // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

    20 // OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

    21 // THE SOFTWARE.

    22 

    23 

    24 import Connectable::*;

    25 import GetPut::*;

    26 import ClientServer::*;

    27 import RegFile::*;

    28 

    29 import FIFO::*;

    30 import FIFOF::*;

    31 import SFIFO::*;

    32 import RWire::*;

    33 

    34 import Trace::*;

    35 import BFIFO::*;

    36 import MemTypes::*;

    37 import ProcTypes::*;

    38 import BRegFile::*;

    39 import BranchPred::*;

    40 //import PathTypes::*;  This is only there to force the debugging

    41 

    42 //AWB includes

    43 `include "asim/provides/low_level_platform_interface.bsh"

    44 `include "asim/provides/soft_connections.bsh"

    45 `include "asim/provides/common_services.bsh"

    46 

    47 // Local includes

    48 //`include "asim/provides/processor_library.bsh" (included above directly)

    49 

    50 `include "asim/provides/common_services.bsh"

    51 `include "asim/provides/processor_library.bsh"

    52 

    53 // Local includes. Look for the correspondingly named .awb files

    54 // workspace/labs/src/mit-6.375/modules/bluespec/mit-6.375/common/

    55 // to find the actual Bluespec files which are used to generate

    56 // these includes.  These files are specific to this audio processing

    57 // pipeline

    58 

    59 `include "asim/provides/audio_pipe_types.bsh"

    60 

    61 //interface CPUToHost;

    62 //  method Bit#(32) cpuToHost(int req);

    63 //endinterface

    64 

    65 interface Proc;

    66 

    67   // Interface from processor to caches

    68   interface Client#(DataReq,DataResp) dmem_client;

    69   interface Client#(InstReq,InstResp) imem_client;

    70 

    71   // Interface for enabling/disabling statistics on the rest of the core

    72   interface Get#(Bool) statsEn_get;

    73 

    74 //  // Interface to host

    75 //  interface CPUToHost tohost;

    76 

    77   // Interface to Audio Pipeline

    78   interface Get#(AudioProcessorUnit) sampleOutput;

    79   interface Put#(AudioProcessorUnit) sampleInput;

    80 	

    81 endinterface

    82 

    83 typedef enum { PCgen, Exec, Writeback } Stage deriving(Eq,Bits);

    84 

    85 //-----------------------------------------------------------

    86 // Register file module

    87 //-----------------------------------------------------------

    88 

    89 interface BRFile;

    90    method Action   wr( Rindx rindx, Bit#(32) data );

    91    method Bit#(32) rd1( Rindx rindx );

    92    method Bit#(32) rd2( Rindx rindx );

    93 endinterface

    94 

    95 module mkBRFile( BRFile );

    96    

    97    RegFile#(Rindx,Bit#(32)) rfile <- mkBRegFile();

    98    

    99    method Action wr( Rindx rindx, Bit#(32) data );

   100       rfile.upd( rindx, data );

   101    endmethod

   102    

   103    method Bit#(32) rd1( Rindx rindx );

   104       return ( rindx == 0 ) ? 0 : rfile.sub(rindx);

   105    endmethod

   106    

   107    method Bit#(32) rd2( Rindx rindx );

   108       return ( rindx == 0 ) ? 0 : rfile.sub(rindx);

   109    endmethod

   110 

   111 endmodule

   112 

   113 //-----------------------------------------------------------

   114 // Helper functions

   115 //-----------------------------------------------------------

   116 

   117 function Bit#(32) slt( Bit#(32) val1, Bit#(32) val2 );

   118    return zeroExtend( pack( signedLT(val1,val2) ) );

   119 endfunction

   120 

   121 function Bit#(32) sltu( Bit#(32) val1, Bit#(32) val2 );

   122    return zeroExtend( pack( val1 < val2 ) );

   123 endfunction

   124 

   125 function Bit#(32) rshft( Bit#(32) val );

   126    return zeroExtend(val[4:0]);

   127 endfunction

   128 

   129 

   130 //-----------------------------------------------------------

   131 // Find funct for wbQ

   132 //-----------------------------------------------------------

   133 function Bool findwbf(Rindx fVal, WBResult cmpVal);

   134   case (cmpVal) matches   

   135      tagged WB_ALU  {data:.res, dest:.rd} :

   136 	return (fVal == rd);

   137      tagged WB_Load .rd  :

   138 	return (fVal == rd);

   139      tagged WB_Store .st :

   140 	return False;

   141      tagged WB_Host .x   :

   142 	return False;

   143   endcase

   144 endfunction

   145 

   146      

   147 //-----------------------------------------------------------

   148 // Stall funct for wbQ

   149 //-----------------------------------------------------------

   150 function Bool stall(Instr inst, SFIFO#(WBResult, Rindx) f);

   151    case (inst) matches

   152       	 // -- Memory Ops ------------------------------------------------      

   153       tagged LW .it :

   154 	 return f.find(it.rbase);

   155       tagged SW {rsrc:.dreg, rbase:.addr, offset:.o} :

   156 	 return (f.find(addr) ||  f.find2(dreg));

   157 

   158 	 // -- Simple Ops ------------------------------------------------      

   159       tagged ADDIU .it : return f.find(it.rsrc);

   160       tagged SLTI  .it : return f.find(it.rsrc);

   161       tagged SLTIU .it : return f.find(it.rsrc);

   162       tagged ANDI  .it : return f.find(it.rsrc);

   163       tagged ORI   .it : return f.find(it.rsrc);

   164       tagged XORI  .it : return f.find(it.rsrc);

   165       

   166       tagged LUI   .it : return f.find(it.rdst);  //this rds/wrs itself

   167       tagged SLL   .it : return f.find(it.rsrc);

   168       tagged SRL   .it : return f.find(it.rsrc);

   169       tagged SRA   .it : return f.find(it.rsrc);

   170       tagged SLLV  .it : return (f.find(it.rsrc) || f.find(it.rshamt));

   171       tagged SRLV  .it : return (f.find(it.rsrc) || f.find(it.rshamt));

   172       tagged SRAV  .it : return (f.find(it.rsrc) || f.find(it.rshamt));

   173       tagged ADDU  .it : return (f.find(it.rsrc1) || f.find2(it.rsrc2));

   174       tagged SUBU  .it : return (f.find(it.rsrc1) || f.find2(it.rsrc2));

   175       tagged AND   .it : return (f.find(it.rsrc1) || f.find2(it.rsrc2));

   176       tagged OR    .it : return (f.find(it.rsrc1) || f.find2(it.rsrc2));

   177       tagged XOR   .it : return (f.find(it.rsrc1) || f.find2(it.rsrc2));

   178       tagged NOR   .it : return (f.find(it.rsrc1) || f.find2(it.rsrc2));

   179       tagged SLT   .it : return (f.find(it.rsrc1) || f.find2(it.rsrc2));

   180       tagged SLTU  .it : return (f.find(it.rsrc1) || f.find2(it.rsrc2));

   181    

   182 

   183       // -- Branches --------------------------------------------------

   184     

   185       tagged BLEZ  .it : return (f.find(it.rsrc));

   186       tagged BGTZ  .it : return (f.find(it.rsrc));

   187       tagged BLTZ  .it : return (f.find(it.rsrc));

   188       tagged BGEZ  .it : return (f.find(it.rsrc));

   189       tagged BEQ   .it : return (f.find(it.rsrc1) || f.find2(it.rsrc2));

   190       tagged BNE   .it : return (f.find(it.rsrc1) || f.find2(it.rsrc2));

   191       

   192       // -- Jumps -----------------------------------------------------

   193       

   194       tagged J     .it : return False;

   195       tagged JR    .it : return f.find(it.rsrc);

   196       tagged JALR  .it : return f.find(it.rsrc);

   197       tagged JAL   .it : return False;

   198       

   199       // -- Cop0 ------------------------------------------------------

   200       

   201       tagged MTC0  .it : return f.find(it.rsrc);      

   202       tagged MFC0  .it : return False; 

   203 

   204       // -- Illegal ---------------------------------------------------

   205 

   206       default : return False;

   207 

   208     endcase

   209 endfunction

   210 //-----------------------------------------------------------

   211 // Reference processor

   212 //-----------------------------------------------------------

   213 

   214 

   215 //(* doc = "synthesis attribute ram_style mkProc distributed;" *)

   216 //(* synthesize *)

   217 

   218 module mkProc( Proc );

   219 

   220    //-----------------------------------------------------------

   221    // State

   222 

   223    // Standard processor state

   224    

   225    Reg#(Addr)  pc    <- mkReg(32'h00001000);

   226    Reg#(Epoch) epoch <- mkReg(0);

   227    Reg#(Stage) stage <- mkReg(PCgen);

   228    BRFile      rf    <- mkBRFile;

   229 

   230    // Branch Prediction

   231    BranchPred               bp <- mkBranchPred();

   232    FIFO#(PCStat)        execpc <- mkLFIFO();

   233    

   234    // Pipelines

   235    FIFO#(PCStat)           pcQ <-mkSizedFIFO(3);

   236    SFIFO#(WBResult, Rindx) wbQ <-mkSFIFO(findwbf);

   237 

   238    // NEED TO ADD CAPABILITY FOR RESET (should be able to just say if I get valid in and these are flagged, clear them.

   239    Reg#(Bit#(32)) cp0_tohost   <- mkReg(0);

   240    Reg#(Bit#(32)) cp0_fromhost <- mkReg(0);

   241    Reg#(Bool)     cp0_statsEn  <- mkReg(False);

   242    Reg#(Bool)     cp0_audioEOF <- mkReg(False);  // Register to let code that EOF is reached

   243    Reg#(Bool)     cp0_progComp <- mkReg(False);  // Register to let processor know that the program is complete (as this terminates)

   244     

   245    // Memory request/response state

   246    

   247    FIFO#(InstReq)  instReqQ    <- mkBFIFO1();

   248    FIFO#(InstResp) instRespQ   <- mkFIFO();

   249 

   250    FIFO#(DataReq)  dataReqQ    <- mkBFIFO1();

   251    FIFO#(DataResp) dataRespQ   <- mkFIFO();

   252 

   253    // Audio I/O

   254    FIFO#(AudioProcessorUnit) inAudioFifo <- mkSizedFIFO(512);

   255    FIFO#(AudioProcessorUnit) outAudioFifo <- mkFIFO;

   256 

   257 

   258    // Statistics state (2010)

   259    //   Reg#(Stat) num_cycles <- mkReg(0);

   260    //   Reg#(Stat) num_inst <- mkReg(0);

   261 

   262    //Or:

   263    // Statistics state

   264   

   265    //rlm: removing these to avoid their broken stupidness.

   266    //STAT num_cycles <- mkStatCounter(`STATS_PROCESSOR_CYCLE_COUNT);

   267    //STAT num_inst <- mkStatCounter(`STATS_PROCESSOR_INST_COUNT);

   268 

   269    //-----------------------------------------------------------

   270    // Rules

   271 

   272    (* descending_urgency = "exec, pcgen" *)

   273    rule pcgen; //( stage == PCgen );

   274       let pc_plus4 = pc + 4;

   275 

   276       traceTiny("mkProc", "pc",pc);

   277       traceTiny("mkProc", "pcgen","P");

   278       instReqQ.enq( LoadReq{ addr:pc, tag:epoch} );

   279       

   280       let next_pc = bp.get(pc);

   281       if (next_pc matches tagged Valid .npc) 

   282 	begin

   283 	   pcQ.enq(PCStat {qpc:pc, qnxtpc:npc, qepoch:epoch});

   284 	   pc <= npc;

   285 	end

   286      else

   287 	 begin

   288 	   pcQ.enq(PCStat {qpc:pc, qnxtpc:pc_plus4, qepoch:epoch});

   289 	   pc <= pc_plus4;

   290 	 end

   291       

   292    endrule

   293 

   294    rule discard (instRespQ.first() matches tagged LoadResp .ld

   295 					      &&& ld.tag != epoch);

   296       traceTiny("mkProc", "stage", "D");

   297       instRespQ.deq();

   298    endrule

   299 

   300    (* conflict_free = "exec, writeback" *)		      

   301    rule exec (instRespQ.first() matches tagged LoadResp.ld

   302 	      &&& (ld.tag == epoch)

   303 	      &&& unpack(ld.data) matches .inst

   304               &&& !stall(inst, wbQ));

   305 

   306       // Some abbreviations

   307       let sext = signExtend;

   308       let zext = zeroExtend;

   309       let sra  = signedShiftRight;

   310       

   311       // Get the instruction

   312       

   313       instRespQ.deq();

   314       Instr inst 

   315       = case ( instRespQ.first() ) matches

   316 	   tagged LoadResp  .ld : return unpack(ld.data);

   317 	   tagged StoreResp .st : return ?;

   318 	endcase;

   319 

   320       // Get the PC info

   321       let instrpc = pcQ.first().qpc;

   322       let pc_plus4 = instrpc + 4;

   323       

   324       Bool branchTaken = False;

   325       Addr newPC = pc_plus4;

   326 

   327       // Tracing

   328       traceTiny("mkProc", "exec","X");

   329       traceTiny("mkProc", "exInstTiny",inst);

   330       traceFull("mkProc", "exInstFull",inst);

   331 

   332       case ( inst ) matches

   333 

   334 	 // -- Memory Ops ------------------------------------------------      

   335 

   336 	 tagged LW .it : 

   337 	    begin

   338                Addr addr = rf.rd1(it.rbase) + sext(it.offset);

   339                dataReqQ.enq( LoadReq{ addr:addr, tag:zeroExtend(it.rdst) } );

   340                wbQ.enq(tagged WB_Load it.rdst);

   341 	    end

   342 

   343 	 tagged SW .it : 

   344 	    begin

   345                Addr addr = rf.rd1(it.rbase) + sext(it.offset);

   346                dataReqQ.enq( StoreReq{ tag:0, addr:addr, data:rf.rd2(it.rsrc) } );

   347                wbQ.enq(tagged WB_Store);

   348 	    end

   349 

   350 	 // -- Simple Ops ------------------------------------------------      

   351 

   352 	 tagged ADDIU .it : 

   353 	    begin

   354 	       Bit#(32) result = rf.rd1(it.rsrc) + sext(it.imm);

   355 	       wbQ.enq(tagged WB_ALU {data:result, dest:it.rdst});

   356 	    end

   357 	 tagged SLTI  .it : wbQ.enq(tagged WB_ALU {dest:it.rdst, data:slt( rf.rd1(it.rsrc), sext(it.imm) )});

   358 	 tagged SLTIU .it : wbQ.enq(tagged WB_ALU {dest:it.rdst, data:sltu( rf.rd1(it.rsrc), sext(it.imm) ) });

   359 	 tagged ANDI  .it : 

   360 	    begin

   361 	       Bit#(32) zext_it_imm = zext(it.imm);

   362 	       wbQ.enq(tagged WB_ALU {dest:it.rdst, data:(rf.rd1(it.rsrc) & zext_it_imm)} );

   363 	    end

   364 	 tagged ORI   .it : 

   365 	    begin

   366 	       Bit#(32) zext_it_imm = zext(it.imm);

   367 	       wbQ.enq(tagged WB_ALU {dest:it.rdst, data:(rf.rd1(it.rsrc) | zext_it_imm)} );

   368 	    end

   369 	 tagged XORI  .it : 

   370 	    begin

   371 	       Bit#(32) zext_it_imm = zext(it.imm);

   372 	       wbQ.enq(tagged WB_ALU {dest: it.rdst, data:(rf.rd1(it.rsrc) ^ zext_it_imm )});

   373 	    end

   374 	 tagged LUI   .it : 

   375 	    begin

   376 	       Bit#(32) zext_it_imm = zext(it.imm);

   377 	       wbQ.enq(tagged WB_ALU {dest: it.rdst, data:(zext_it_imm << 32'd16) });

   378 	    end

   379 	 

   380 	 tagged SLL   .it : 

   381 	    begin

   382 	       Bit#(32) zext_it_shamt = zext(it.shamt);

   383 	       wbQ.enq(tagged WB_ALU {dest: it.rdst, data:(rf.rd1(it.rsrc) << zext_it_shamt )} );

   384 	    end

   385 	 tagged SRL   .it : 

   386 	    begin

   387 	       Bit#(32) zext_it_shamt = zext(it.shamt);

   388 	       wbQ.enq(tagged WB_ALU {dest: it.rdst, data:(rf.rd1(it.rsrc) >> zext_it_shamt )});

   389 	    end

   390 	 tagged SRA   .it : 

   391 	    begin

   392 	       Bit#(32) zext_it_shamt = zext(it.shamt);

   393 	       wbQ.enq(tagged WB_ALU {dest: it.rdst, data:sra( rf.rd1(it.rsrc), zext_it_shamt )});

   394 	    end

   395 	 tagged SLLV  .it : wbQ.enq(tagged WB_ALU {dest: it.rdst, data:(rf.rd1(it.rsrc) << rshft(rf.rd2(it.rshamt)) )});

   396 	 tagged SRLV  .it : wbQ.enq(tagged WB_ALU {dest: it.rdst, data:(rf.rd1(it.rsrc) >> rshft(rf.rd2(it.rshamt)) )} );

   397 	 tagged SRAV  .it : wbQ.enq(tagged WB_ALU {dest: it.rdst, data:sra( rf.rd1(it.rsrc), rshft(rf.rd2(it.rshamt)) ) });

   398 	 tagged ADDU  .it : wbQ.enq(tagged WB_ALU {dest: it.rdst, data:(rf.rd1(it.rsrc1) + rf.rd2(it.rsrc2) )} );

   399 	 tagged SUBU  .it : wbQ.enq(tagged WB_ALU {dest: it.rdst, data:(rf.rd1(it.rsrc1) - rf.rd2(it.rsrc2) )} );

   400 	 tagged AND   .it : wbQ.enq(tagged WB_ALU {dest: it.rdst, data:(rf.rd1(it.rsrc1) & rf.rd2(it.rsrc2) )} );

   401 	 tagged OR    .it : wbQ.enq(tagged WB_ALU {dest: it.rdst, data:(rf.rd1(it.rsrc1) | rf.rd2(it.rsrc2) )} );

   402 	 tagged XOR   .it : wbQ.enq(tagged WB_ALU {dest: it.rdst, data:(rf.rd1(it.rsrc1) ^ rf.rd2(it.rsrc2) )} );

   403 	 tagged NOR   .it : wbQ.enq(tagged WB_ALU {dest: it.rdst, data:(~(rf.rd1(it.rsrc1) | rf.rd2(it.rsrc2)) )} );

   404 	 tagged SLT   .it : wbQ.enq(tagged WB_ALU {dest: it.rdst, data:slt( rf.rd1(it.rsrc1), rf.rd2(it.rsrc2) ) });

   405 	 tagged SLTU  .it : wbQ.enq(tagged WB_ALU {dest: it.rdst, data:sltu( rf.rd1(it.rsrc1), rf.rd2(it.rsrc2) ) });

   406 

   407 	 // -- Branches --------------------------------------------------

   408 

   409 	 tagged BLEZ  .it : 

   410             if ( signedLE( rf.rd1(it.rsrc), 0 ) )

   411 	       begin

   412 		  newPC = pc_plus4 + (sext(it.offset) << 2);

   413 		  branchTaken = True;

   414 	       end

   415 

   416 	 tagged BGTZ  .it : 

   417             if ( signedGT( rf.rd1(it.rsrc), 0 ) ) 

   418                begin 

   419 		  newPC = pc_plus4 + (sext(it.offset) << 2);

   420 		  branchTaken = True;

   421 	       end

   422 

   423 	 tagged BLTZ  .it : 

   424             if ( signedLT( rf.rd1(it.rsrc), 0 ) )

   425                begin 

   426 		  newPC = pc_plus4 + (sext(it.offset) << 2);

   427 		  branchTaken = True;

   428 	       end

   429 		  

   430 	 tagged BGEZ  .it : 

   431             if ( signedGE( rf.rd1(it.rsrc), 0 ) )

   432                begin 

   433 		  newPC = pc_plus4 + (sext(it.offset) << 2);		  

   434 		  branchTaken = True;

   435 	       end

   436 

   437       tagged BEQ   .it : 

   438         if ( rf.rd1(it.rsrc1) == rf.rd2(it.rsrc2) )

   439           begin 

   440 	     newPC = pc_plus4 + (sext(it.offset) << 2);

   441 	     branchTaken = True;

   442 	  end

   443 

   444       tagged BNE   .it : 

   445         if ( rf.rd1(it.rsrc1) != rf.rd2(it.rsrc2) )

   446           begin 

   447 	     newPC = pc_plus4 + (sext(it.offset) << 2);

   448 	     branchTaken = True;

   449 	  end

   450 

   451       // -- Jumps -----------------------------------------------------

   452       

   453       tagged J     .it : 

   454         begin 

   455 	   newPC = { pc_plus4[31:28], it.target, 2'b0 };

   456 	   branchTaken = True;

   457 	end

   458       

   459       tagged JR    .it : 

   460         begin

   461 	   newPC = rf.rd1(it.rsrc);

   462 	   branchTaken = True;

   463 	end

   464 

   465       tagged JAL   .it : 

   466        begin

   467           wbQ.enq(tagged WB_ALU {dest:31, data:pc_plus4 });

   468           newPC = { pc_plus4[31:28], it.target, 2'b0 };		  

   469 	  branchTaken = True;

   470        end

   471 

   472       tagged JALR  .it : 

   473        begin

   474           wbQ.enq(tagged WB_ALU {dest:it.rdst, data:pc_plus4 });

   475           newPC = rf.rd1(it.rsrc);

   476 	  branchTaken = True;

   477        end

   478 

   479       // -- Cop0 ------------------------------------------------------

   480       

   481       tagged MTC0  .it : //Recieve things from host computer

   482 	 begin

   483 //	    $display( " PROCESSOR MTC0 call\n");

   484             case ( it.cop0dst )

   485 	       5'd10 : cp0_statsEn <= unpack(truncate(rf.rd1(it.rsrc)));

   486 	       5'd21 : cp0_tohost  <= truncate(rf.rd1(it.rsrc));

   487 	       5'd26 : cp0_progComp <= unpack(truncate(rf.rd1(it.rsrc))); //states audio program completed and termination okay

   488  	       5'd27 : outAudioFifo.enq(tagged Sample unpack(truncate(rf.rd1(it.rsrc))));  //Bit size is 16 not 32 

   489 	       default :

   490 	       $display( " RTL-ERROR : %m : Illegal MTC0 cop0dst register!" );

   491 	    endcase

   492 	    wbQ.enq(tagged WB_Host 0); //no idea wwhat this actually should be.

   493 	 end

   494 

   495 //this is host stuff?

   496       tagged MFC0  .it :  //Things out

   497 	 begin

   498             case ( it.cop0src )

   499 	    // not actually an ALU instruction but don't have the format otherwise

   500                5'd10 : wbQ.enq(tagged WB_ALU {dest:it.rdst, data:zext(pack(cp0_statsEn)) });

   501                5'd20 : wbQ.enq(tagged WB_ALU {dest:it.rdst, data:cp0_fromhost });

   502                5'd21 : wbQ.enq(tagged WB_ALU {dest:it.rdst, data:cp0_tohost   });

   503 	       5'd25 : begin

   504 //			  $display( "**** EOF Requested\n ");

   505 			  let sample = inAudioFifo.first();

   506 			  case (sample) matches

   507 			     tagged EndOfFile :

   508 				begin

   509 				   $display("PROCESSOR sent toC EOF");

   510 				   wbQ.enq(tagged WB_ALU {dest:it.rdst, data:zext(pack(True)) });  // Reading clears bit

   511 				   inAudioFifo.deq;

   512 			        end

   513 			     tagged Sample .data:

   514 				   wbQ.enq(tagged WB_ALU {dest:it.rdst, data:zext(pack(False)) });  // Reading clears bit

   515 			  endcase

   516 		       end

   517 	       5'd28 : begin

   518 //			  $display( "***** Reqesting Sample \n");

   519 			  let sample = inAudioFifo.first();        // is this going to cause perf. delay?

   520 			  if (sample matches tagged Sample .audio) // if it is EOF another rule sets the cp0_audioEOF  

   521 	     		     wbQ.enq(tagged WB_ALU {dest:it.rdst, data:zext(pack(audio)) });  // do I need pack?

   522 			  else $display ( "Audio File EOF Reached.  Invalid sample request.");

   523 			  inAudioFifo.deq();

   524 		       end

   525               default : 

   526                 $display( " RTL-ERROR : %m : Illegal MFC0 cop0src register!" );

   527             endcase

   528 	end

   529 

   530       // -- Illegal ---------------------------------------------------

   531 

   532       default : 

   533         $display( " RTL-ERROR : %m : Illegal instruction !" );

   534 

   535     endcase

   536 

   537 //evaluate branch prediction

   538      Addr ppc = pcQ.first().qnxtpc; //predicted branch

   539      if (ppc != newPC) //prediction wrong

   540        begin

   541 	  epoch <= pcQ.first().qepoch + 1;

   542 	  bp.upd(instrpc, newPC); //update branch predictor

   543 	  pcQ.clear();

   544 	  pc <= newPC;

   545        end

   546      else

   547 	pcQ.deq();

   548    //rlm: removing

   549    // if ( cp0_statsEn )

   550    //   num_inst.incr();

   551 

   552   endrule

   553 

   554   rule writeback; // ( stage == Writeback );

   555      traceTiny("mkProc", "writeback","W");

   556      

   557 

   558     // get what to do off the writeback queue

   559      wbQ.deq();

   560      case (wbQ.first()) matches

   561 	tagged WB_ALU {data:.res, dest:.rdst} : rf.wr(rdst, res);

   562 	tagged WB_Load .regWr : 

   563 	   begin

   564 	      dataRespQ.deq();

   565 	      if (dataRespQ.first() matches tagged LoadResp .ld)

   566 		rf.wr(truncate(ld.tag), ld.data); // no need to use Rindx from queue?  Duplicate?

   567 	   end

   568 	tagged WB_Store : dataRespQ.deq();

   569 	tagged WB_Host .dat : noAction;

   570      endcase

   571            

   572   endrule

   573 

   574 //rlm remove

   575  // rule inc_num_cycles;

   576  //   if ( cp0_statsEn )

   577  //     num_cycles.incr();

   578  // endrule

   579 

   580 /*

   581  // for now, we don't do anything.

   582   rule connectAudioReqResp;

   583     $display("rlm: PROCESSOR copies a datum\n");

   584     outAudioFifo.enq(inAudioFifo.first());

   585     inAudioFifo.deq;

   586   endrule

   587 */

   588 /*

   589   rule flagAudioEnd (inAudioFifo.first() matches tagged EndOfFile);

   590      $display (" PROCESSOR End Audio Flag Set ");

   591      cp0_audioEOF <= True;

   592      inAudioFifo.deq;

   593   endrule

   594 */

   595   rule sendProcEnd (cp0_progComp);

   596      $display (" PROCESSOR Says Program Complete ");

   597      outAudioFifo.enq(tagged EndOfFile);

   598      cp0_progComp <= False;  //only send one.  And functions to reset

   599   endrule

   600 

   601    

   602   //-----------------------------------------------------------

   603   // Methods

   604 

   605   interface Client imem_client;

   606     interface Get request  = fifoToGet(instReqQ);

   607     interface Put response = fifoToPut(instRespQ);

   608   endinterface

   609 

   610   interface Client dmem_client;

   611     interface Get request  = fifoToGet(dataReqQ);

   612     interface Put response = fifoToPut(dataRespQ);

   613   endinterface

   614 

   615   interface Get statsEn_get = toGet(asReg(cp0_statsEn));

   616 

   617   /*

   618   interface CPUToHost tohost;

   619     method Bit#(32) cpuToHost(int req);

   620       return (case (req)

   621        0: cp0_tohost;

   622        1: pc;

   623        2: zeroExtend(pack(stage));

   624       endcase);

   625     endmethod

   626   endinterface

   627   */

   628    

   629   interface Get sampleOutput = fifoToGet(outAudioFifo);

   630   interface Put sampleInput = fifoToPut(inAudioFifo);

   631 

   632 endmodule

   633
author	rlm
date	Sun, 09 May 2010 23:12:15 -0400
parents	2991344775f8
children	1d5cbb5343d2