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Processor.v
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Processor.v
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`timescale 1ns / 1ps
/*
* File : Processor.v
* Project : University of Utah, XUM Project MIPS32 core
* Creator(s) : Grant Ayers (ayers@cs.utah.edu)
*
* Modification History:
* Rev Date Initials Description of Change
* 1.0 23-Jul-2011 GEA Initial design.
* 2.0 26-May-2012 GEA Release version with CP0.
* 2.01 1-Nov-2012 GEA Fixed issue with Jal.
* *** *********** *** [Further changes tracked in source control]
*
* Standards/Formatting:
* Verilog 2001, 4 soft tab, wide column.
*
* Description:
* The top-level MIPS32 Processor. This file is mostly the instantiation
* and wiring of the building blocks of the processor according to the
* hardware design diagram. It contains very little logic itself.
*/
module Processor(
input clock,
input reset,
input [4:0] Interrupts, // 5 general-purpose hardware interrupts
input NMI, // Non-maskable interrupt
// Data Memory Interface
input [31:0] DataMem_In,
input DataMem_Ack,
output DataMem_Read,
output [3:0] DataMem_Write, // 4-bit Write, one for each byte in word.
output [29:0] DataMem_Address, // Addresses are words, not bytes.
output [31:0] DataMem_Out,
// Instruction Memory Interface
input [31:0] InstMem_In,
output [29:0] InstMem_Address, // Addresses are words, not bytes.
input InstMem_Ack,
output InstMem_Read,
output [7:0] IP // Pending interrupts (diagnostic)
);
`include "MIPS_Parameters.v"
/*** MIPS Instruction and Components (ID Stage) ***/
wire [31:0] Instruction;
wire [5:0] OpCode = Instruction[31:26];
wire [4:0] Rs = Instruction[25:21];
wire [4:0] Rt = Instruction[20:16];
wire [4:0] Rd = Instruction[15:11];
wire [5:0] Funct = Instruction[5:0];
wire [15:0] Immediate = Instruction[15:0];
wire [25:0] JumpAddress = Instruction[25:0];
wire [2:0] Cp0_Sel = Instruction[2:0];
/*** IF (Instruction Fetch) Signals ***/
wire IF_Stall, IF_Flush;
wire IF_EXC_AdIF;
wire IF_Exception_Stall;
wire IF_Exception_Flush;
wire IF_IsBDS;
wire [31:0] IF_PCAdd4, IF_PC_PreExc, IF_PCIn, IF_PCOut, IF_Instruction;
/*** ID (Instruction Decode) Signals ***/
wire ID_Stall;
wire [1:0] ID_PCSrc;
wire [1:0] ID_RsFwdSel, ID_RtFwdSel;
wire ID_Link, ID_Movn, ID_Movz;
wire ID_SignExtend;
wire ID_LLSC;
wire ID_RegDst, ID_ALUSrcImm, ID_MemWrite, ID_MemRead, ID_MemByte, ID_MemHalf, ID_MemSignExtend, ID_RegWrite, ID_MemtoReg;
wire [4:0] ID_ALUOp;
wire ID_Mfc0, ID_Mtc0, ID_Eret;
wire ID_NextIsDelay;
wire ID_CanErr, ID_ID_CanErr, ID_EX_CanErr, ID_M_CanErr;
wire ID_KernelMode;
wire ID_ReverseEndian;
wire ID_Trap, ID_TrapCond;
wire ID_EXC_Sys, ID_EXC_Bp, ID_EXC_RI;
wire ID_Exception_Stall;
wire ID_Exception_Flush;
wire ID_PCSrc_Exc;
wire [31:0] ID_ExceptionPC;
wire ID_CP1, ID_CP2, ID_CP3;
wire [31:0] ID_PCAdd4;
wire [31:0] ID_ReadData1_RF, ID_ReadData1_End;
wire [31:0] ID_ReadData2_RF, ID_ReadData2_End;
wire [31:0] CP0_RegOut;
wire ID_CmpEQ, ID_CmpGZ, ID_CmpLZ, ID_CmpGEZ, ID_CmpLEZ;
wire [29:0] ID_SignExtImm = (ID_SignExtend & Immediate[15]) ? {14'h3FFF, Immediate} : {14'h0000, Immediate};
wire [31:0] ID_ImmLeftShift2 = {ID_SignExtImm[29:0], 2'b00};
wire [31:0] ID_JumpAddress = {ID_PCAdd4[31:28], JumpAddress[25:0], 2'b00};
wire [31:0] ID_BranchAddress;
wire [31:0] ID_RestartPC;
wire ID_IsBDS;
wire ID_Left, ID_Right;
wire ID_IsFlushed;
/*** EX (Execute) Signals ***/
wire EX_ALU_Stall, EX_Stall;
wire [1:0] EX_RsFwdSel, EX_RtFwdSel;
wire EX_Link;
wire [1:0] EX_LinkRegDst;
wire EX_ALUSrcImm;
wire [4:0] EX_ALUOp;
wire EX_Movn, EX_Movz;
wire EX_LLSC;
wire EX_MemRead, EX_MemWrite, EX_MemByte, EX_MemHalf, EX_MemSignExtend, EX_RegWrite, EX_MemtoReg;
wire [4:0] EX_Rs, EX_Rt;
wire EX_WantRsByEX, EX_NeedRsByEX, EX_WantRtByEX, EX_NeedRtByEX;
wire EX_Trap, EX_TrapCond;
wire EX_CanErr, EX_EX_CanErr, EX_M_CanErr;
wire EX_KernelMode;
wire EX_ReverseEndian;
wire EX_Exception_Stall;
wire EX_Exception_Flush;
wire [31:0] EX_ReadData1_PR, EX_ReadData1_Fwd, EX_ReadData2_PR, EX_ReadData2_Fwd, EX_ReadData2_Imm;
wire [31:0] EX_SignExtImm;
wire [4:0] EX_Rd, EX_RtRd, EX_Shamt;
wire [31:0] EX_ALUResult;
wire EX_BZero;
wire EX_EXC_Ov;
wire [31:0] EX_RestartPC;
wire EX_IsBDS;
wire EX_Left, EX_Right;
/*** MEM (Memory) Signals ***/
wire M_Stall, M_Stall_Controller;
wire M_LLSC;
wire M_MemRead, M_MemWrite, M_MemByte, M_MemHalf, M_MemSignExtend;
wire M_RegWrite, M_MemtoReg;
wire M_WriteDataFwdSel;
wire M_EXC_AdEL, M_EXC_AdES;
wire M_M_CanErr;
wire M_KernelMode;
wire M_ReverseEndian;
wire M_Trap, M_TrapCond;
wire M_EXC_Tr;
wire M_Exception_Flush;
wire [31:0] M_ALUResult, M_ReadData2_PR;
wire [4:0] M_RtRd;
wire [31:0] M_MemReadData;
wire [31:0] M_RestartPC;
wire M_IsBDS;
wire [31:0] M_WriteData_Pre;
wire M_Left, M_Right;
wire M_Exception_Stall;
/*** WB (Writeback) Signals ***/
wire WB_Stall, WB_RegWrite, WB_MemtoReg;
wire [31:0] WB_ReadData, WB_ALUResult;
wire [4:0] WB_RtRd;
wire [31:0] WB_WriteData;
/*** Other Signals ***/
wire [7:0] ID_DP_Hazards, HAZ_DP_Hazards;
/*** Assignments ***/
assign IF_Instruction = (IF_Stall) ? 32'h00000000 : InstMem_In;
assign IF_IsBDS = ID_NextIsDelay;
assign HAZ_DP_Hazards = {ID_DP_Hazards[7:4], EX_WantRsByEX, EX_NeedRsByEX, EX_WantRtByEX, EX_NeedRtByEX};
assign IF_EXC_AdIF = IF_PCOut[1] | IF_PCOut[0];
assign ID_CanErr = ID_ID_CanErr | ID_EX_CanErr | ID_M_CanErr;
assign EX_CanErr = EX_EX_CanErr | EX_M_CanErr;
// External Memory Interface
reg IRead, IReadMask;
assign InstMem_Address = IF_PCOut[31:2];
assign DataMem_Address = M_ALUResult[31:2];
always @(posedge clock) begin
IRead <= (reset) ? 1'b1 : ~InstMem_Ack;
IReadMask <= (reset) ? 1'b0 : ((IRead & InstMem_Ack) ? 1'b1 : ((~IF_Stall) ? 1'b0 : IReadMask));
end
assign InstMem_Read = IRead & ~IReadMask;
/*** Datapath Controller ***/
Control Controller (
.ID_Stall (ID_Stall),
.OpCode (OpCode),
.Funct (Funct),
.Rs (Rs),
.Rt (Rt),
.Cmp_EQ (ID_CmpEQ),
.Cmp_GZ (ID_CmpGZ),
.Cmp_GEZ (ID_CmpGEZ),
.Cmp_LZ (ID_CmpLZ),
.Cmp_LEZ (ID_CmpLEZ),
.IF_Flush (IF_Flush),
.DP_Hazards (ID_DP_Hazards),
.PCSrc (ID_PCSrc),
.SignExtend (ID_SignExtend),
.Link (ID_Link),
.Movn (ID_Movn),
.Movz (ID_Movz),
.Mfc0 (ID_Mfc0),
.Mtc0 (ID_Mtc0),
.CP1 (ID_CP1),
.CP2 (ID_CP2),
.CP3 (ID_CP3),
.Eret (ID_Eret),
.Trap (ID_Trap),
.TrapCond (ID_TrapCond),
.EXC_Sys (ID_EXC_Sys),
.EXC_Bp (ID_EXC_Bp),
.EXC_RI (ID_EXC_RI),
.ID_CanErr (ID_ID_CanErr),
.EX_CanErr (ID_EX_CanErr),
.M_CanErr (ID_M_CanErr),
.NextIsDelay (ID_NextIsDelay),
.RegDst (ID_RegDst),
.ALUSrcImm (ID_ALUSrcImm),
.ALUOp (ID_ALUOp),
.LLSC (ID_LLSC),
.MemWrite (ID_MemWrite),
.MemRead (ID_MemRead),
.MemByte (ID_MemByte),
.MemHalf (ID_MemHalf),
.MemSignExtend (ID_MemSignExtend),
.Left (ID_Left),
.Right (ID_Right),
.RegWrite (ID_RegWrite),
.MemtoReg (ID_MemtoReg)
);
/*** Hazard and Forward Control Unit ***/
Hazard_Detection HazardControl (
.DP_Hazards (HAZ_DP_Hazards),
.ID_Rs (Rs),
.ID_Rt (Rt),
.EX_Rs (EX_Rs),
.EX_Rt (EX_Rt),
.EX_RtRd (EX_RtRd),
.MEM_RtRd (M_RtRd),
.WB_RtRd (WB_RtRd),
.EX_Link (EX_Link),
.EX_RegWrite (EX_RegWrite),
.MEM_RegWrite (M_RegWrite),
.WB_RegWrite (WB_RegWrite),
.MEM_MemRead (M_MemRead),
.MEM_MemWrite (M_MemWrite),
.InstMem_Read (InstMem_Read),
.InstMem_Ack (InstMem_Ack),
.Mfc0 (ID_Mfc0),
.IF_Exception_Stall (IF_Exception_Stall),
.ID_Exception_Stall (ID_Exception_Stall),
.EX_Exception_Stall (EX_Exception_Stall),
.EX_ALU_Stall (EX_ALU_Stall),
.M_Stall_Controller (M_Stall_Controller),
.IF_Stall (IF_Stall),
.ID_Stall (ID_Stall),
.EX_Stall (EX_Stall),
.M_Stall (M_Stall),
.WB_Stall (WB_Stall),
.ID_RsFwdSel (ID_RsFwdSel),
.ID_RtFwdSel (ID_RtFwdSel),
.EX_RsFwdSel (EX_RsFwdSel),
.EX_RtFwdSel (EX_RtFwdSel),
.M_WriteDataFwdSel (M_WriteDataFwdSel)
);
/*** Coprocessor 0: Exceptions and Interrupts ***/
CPZero CP0 (
.clock (clock),
.Mfc0 (ID_Mfc0),
.Mtc0 (ID_Mtc0),
.IF_Stall (IF_Stall),
.ID_Stall (ID_Stall),
.COP1 (ID_CP1),
.COP2 (ID_CP2),
.COP3 (ID_CP3),
.ERET (ID_Eret),
.Rd (Rd),
.Sel (Cp0_Sel),
.Reg_In (ID_ReadData2_End),
.Reg_Out (CP0_RegOut),
.KernelMode (ID_KernelMode),
.ReverseEndian (ID_ReverseEndian),
.Int (Interrupts),
.reset (reset),
.EXC_NMI (NMI),
.EXC_AdIF (IF_EXC_AdIF),
.EXC_AdEL (M_EXC_AdEL),
.EXC_AdES (M_EXC_AdES),
.EXC_Ov (EX_EXC_Ov),
.EXC_Tr (M_EXC_Tr),
.EXC_Sys (ID_EXC_Sys),
.EXC_Bp (ID_EXC_Bp),
.EXC_RI (ID_EXC_RI),
.ID_RestartPC (ID_RestartPC),
.EX_RestartPC (EX_RestartPC),
.M_RestartPC (M_RestartPC),
.ID_IsFlushed (ID_IsFlushed),
.IF_IsBD (IF_IsBDS),
.ID_IsBD (ID_IsBDS),
.EX_IsBD (EX_IsBDS),
.M_IsBD (M_IsBDS),
.BadAddr_M (M_ALUResult),
.BadAddr_IF (IF_PCOut),
.ID_CanErr (ID_CanErr),
.EX_CanErr (EX_CanErr),
.M_CanErr (M_M_CanErr),
.IF_Exception_Stall (IF_Exception_Stall),
.ID_Exception_Stall (ID_Exception_Stall),
.EX_Exception_Stall (EX_Exception_Stall),
.M_Exception_Stall (M_Exception_Stall),
.IF_Exception_Flush (IF_Exception_Flush),
.ID_Exception_Flush (ID_Exception_Flush),
.EX_Exception_Flush (EX_Exception_Flush),
.M_Exception_Flush (M_Exception_Flush),
.Exc_PC_Sel (ID_PCSrc_Exc),
.Exc_PC_Out (ID_ExceptionPC),
.IP (IP)
);
/*** PC Source Non-Exception Mux ***/
Mux4 #(.WIDTH(32)) PCSrcStd_Mux (
.sel (ID_PCSrc),
.in0 (IF_PCAdd4),
.in1 (ID_JumpAddress),
.in2 (ID_BranchAddress),
.in3 (ID_ReadData1_End),
.out (IF_PC_PreExc)
);
/*** PC Source Exception Mux ***/
Mux2 #(.WIDTH(32)) PCSrcExc_Mux (
.sel (ID_PCSrc_Exc),
.in0 (IF_PC_PreExc),
.in1 (ID_ExceptionPC),
.out (IF_PCIn)
);
/*** Program Counter (MIPS spec is 0xBFC00000 starting address) ***/
Register #(.WIDTH(32), .INIT(`EXC_Vector_Base_Reset)) PC (
.clock (clock),
.reset (reset),
//.enable (~IF_Stall), // XXX verify. HERE. Was 1 but on stall latches PC+4, ad nauseum.
.enable (~(IF_Stall | ID_Stall)),
.D (IF_PCIn),
.Q (IF_PCOut)
);
/*** PC +4 Adder ***/
Add PC_Add4 (
.A (IF_PCOut),
.B (32'h00000004),
.C (IF_PCAdd4)
);
/*** Instruction Fetch -> Instruction Decode Stage Register ***/
IFID_Stage IFID (
.clock (clock),
.reset (reset),
.IF_Flush (IF_Exception_Flush | IF_Flush),
.IF_Stall (IF_Stall),
.ID_Stall (ID_Stall),
.IF_Instruction (IF_Instruction),
.IF_PCAdd4 (IF_PCAdd4),
.IF_PC (IF_PCOut),
.IF_IsBDS (IF_IsBDS),
.ID_Instruction (Instruction),
.ID_PCAdd4 (ID_PCAdd4),
.ID_RestartPC (ID_RestartPC),
.ID_IsBDS (ID_IsBDS),
.ID_IsFlushed (ID_IsFlushed)
);
/*** Register File ***/
RegisterFile RegisterFile (
.clock (clock),
.reset (reset),
.ReadReg1 (Rs),
.ReadReg2 (Rt),
.WriteReg (WB_RtRd),
.WriteData (WB_WriteData),
.RegWrite (WB_RegWrite),
.ReadData1 (ID_ReadData1_RF),
.ReadData2 (ID_ReadData2_RF)
);
/*** ID Rs Forwarding/Link Mux ***/
Mux4 #(.WIDTH(32)) IDRsFwd_Mux (
.sel (ID_RsFwdSel),
.in0 (ID_ReadData1_RF),
.in1 (M_ALUResult),
.in2 (WB_WriteData),
.in3 (32'hxxxxxxxx),
.out (ID_ReadData1_End)
);
/*** ID Rt Forwarding/CP0 Mfc0 Mux ***/
Mux4 #(.WIDTH(32)) IDRtFwd_Mux (
.sel (ID_RtFwdSel),
.in0 (ID_ReadData2_RF),
.in1 (M_ALUResult),
.in2 (WB_WriteData),
.in3 (CP0_RegOut),
.out (ID_ReadData2_End)
);
/*** Condition Compare Unit ***/
Compare Compare (
.A (ID_ReadData1_End),
.B (ID_ReadData2_End),
.EQ (ID_CmpEQ),
.GZ (ID_CmpGZ),
.LZ (ID_CmpLZ),
.GEZ (ID_CmpGEZ),
.LEZ (ID_CmpLEZ)
);
/*** Branch Address Adder ***/
Add BranchAddress_Add (
.A (ID_PCAdd4),
.B (ID_ImmLeftShift2),
.C (ID_BranchAddress)
);
/*** Instruction Decode -> Execute Pipeline Stage ***/
IDEX_Stage IDEX (
.clock (clock),
.reset (reset),
.ID_Flush (ID_Exception_Flush),
.ID_Stall (ID_Stall),
.EX_Stall (EX_Stall),
.ID_Link (ID_Link),
.ID_RegDst (ID_RegDst),
.ID_ALUSrcImm (ID_ALUSrcImm),
.ID_ALUOp (ID_ALUOp),
.ID_Movn (ID_Movn),
.ID_Movz (ID_Movz),
.ID_LLSC (ID_LLSC),
.ID_MemRead (ID_MemRead),
.ID_MemWrite (ID_MemWrite),
.ID_MemByte (ID_MemByte),
.ID_MemHalf (ID_MemHalf),
.ID_MemSignExtend (ID_MemSignExtend),
.ID_Left (ID_Left),
.ID_Right (ID_Right),
.ID_RegWrite (ID_RegWrite),
.ID_MemtoReg (ID_MemtoReg),
.ID_ReverseEndian (ID_ReverseEndian),
.ID_Rs (Rs),
.ID_Rt (Rt),
.ID_WantRsByEX (ID_DP_Hazards[3]),
.ID_NeedRsByEX (ID_DP_Hazards[2]),
.ID_WantRtByEX (ID_DP_Hazards[1]),
.ID_NeedRtByEX (ID_DP_Hazards[0]),
.ID_KernelMode (ID_KernelMode),
.ID_RestartPC (ID_RestartPC),
.ID_IsBDS (ID_IsBDS),
.ID_Trap (ID_Trap),
.ID_TrapCond (ID_TrapCond),
.ID_EX_CanErr (ID_EX_CanErr),
.ID_M_CanErr (ID_M_CanErr),
.ID_ReadData1 (ID_ReadData1_End),
.ID_ReadData2 (ID_ReadData2_End),
.ID_SignExtImm (ID_SignExtImm[16:0]),
.EX_Link (EX_Link),
.EX_LinkRegDst (EX_LinkRegDst),
.EX_ALUSrcImm (EX_ALUSrcImm),
.EX_ALUOp (EX_ALUOp),
.EX_Movn (EX_Movn),
.EX_Movz (EX_Movz),
.EX_LLSC (EX_LLSC),
.EX_MemRead (EX_MemRead),
.EX_MemWrite (EX_MemWrite),
.EX_MemByte (EX_MemByte),
.EX_MemHalf (EX_MemHalf),
.EX_MemSignExtend (EX_MemSignExtend),
.EX_Left (EX_Left),
.EX_Right (EX_Right),
.EX_RegWrite (EX_RegWrite),
.EX_MemtoReg (EX_MemtoReg),
.EX_ReverseEndian (EX_ReverseEndian),
.EX_Rs (EX_Rs),
.EX_Rt (EX_Rt),
.EX_WantRsByEX (EX_WantRsByEX),
.EX_NeedRsByEX (EX_NeedRsByEX),
.EX_WantRtByEX (EX_WantRtByEX),
.EX_NeedRtByEX (EX_NeedRtByEX),
.EX_KernelMode (EX_KernelMode),
.EX_RestartPC (EX_RestartPC),
.EX_IsBDS (EX_IsBDS),
.EX_Trap (EX_Trap),
.EX_TrapCond (EX_TrapCond),
.EX_EX_CanErr (EX_EX_CanErr),
.EX_M_CanErr (EX_M_CanErr),
.EX_ReadData1 (EX_ReadData1_PR),
.EX_ReadData2 (EX_ReadData2_PR),
.EX_SignExtImm (EX_SignExtImm),
.EX_Rd (EX_Rd),
.EX_Shamt (EX_Shamt)
);
/*** EX Rs Forwarding Mux ***/
Mux4 #(.WIDTH(32)) EXRsFwd_Mux (
.sel (EX_RsFwdSel),
.in0 (EX_ReadData1_PR),
.in1 (M_ALUResult),
.in2 (WB_WriteData),
.in3 (EX_RestartPC),
.out (EX_ReadData1_Fwd)
);
/*** EX Rt Forwarding / Link Mux ***/
Mux4 #(.WIDTH(32)) EXRtFwdLnk_Mux (
.sel (EX_RtFwdSel),
.in0 (EX_ReadData2_PR),
.in1 (M_ALUResult),
.in2 (WB_WriteData),
.in3 (32'h00000008),
.out (EX_ReadData2_Fwd)
);
/*** EX ALU Immediate Mux ***/
Mux2 #(.WIDTH(32)) EXALUImm_Mux (
.sel (EX_ALUSrcImm),
.in0 (EX_ReadData2_Fwd),
.in1 (EX_SignExtImm),
.out (EX_ReadData2_Imm)
);
/*** EX RtRd / Link Mux ***/
Mux4 #(.WIDTH(5)) EXRtRdLnk_Mux (
.sel (EX_LinkRegDst),
.in0 (EX_Rt),
.in1 (EX_Rd),
.in2 (5'b11111),
.in3 (5'bxxxxx),
.out (EX_RtRd)
);
/*** Arithmetic Logic Unit ***/
ALU ALU (
.clock (clock),
.reset (reset),
.EX_Stall (EX_Stall),
.EX_Flush (EX_Exception_Flush),
.A (EX_ReadData1_Fwd),
.B (EX_ReadData2_Imm),
.Operation (EX_ALUOp),
.Shamt (EX_Shamt),
.Result (EX_ALUResult),
.BZero (EX_BZero),
.EXC_Ov (EX_EXC_Ov),
.ALU_Stall (EX_ALU_Stall)
);
/*** Execute -> Memory Pipeline Stage ***/
EXMEM_Stage EXMEM (
.clock (clock),
.reset (reset),
.EX_Flush (EX_Exception_Flush),
.EX_Stall (EX_Stall),
.M_Stall (M_Stall),
.EX_Movn (EX_Movn),
.EX_Movz (EX_Movz),
.EX_BZero (EX_BZero),
.EX_RegWrite (EX_RegWrite),
.EX_MemtoReg (EX_MemtoReg),
.EX_ReverseEndian (EX_ReverseEndian),
.EX_LLSC (EX_LLSC),
.EX_MemRead (EX_MemRead),
.EX_MemWrite (EX_MemWrite),
.EX_MemByte (EX_MemByte),
.EX_MemHalf (EX_MemHalf),
.EX_MemSignExtend (EX_MemSignExtend),
.EX_Left (EX_Left),
.EX_Right (EX_Right),
.EX_KernelMode (EX_KernelMode),
.EX_RestartPC (EX_RestartPC),
.EX_IsBDS (EX_IsBDS),
.EX_Trap (EX_Trap),
.EX_TrapCond (EX_TrapCond),
.EX_M_CanErr (EX_M_CanErr),
.EX_ALU_Result (EX_ALUResult),
.EX_ReadData2 (EX_ReadData2_Fwd),
.EX_RtRd (EX_RtRd),
.M_RegWrite (M_RegWrite),
.M_MemtoReg (M_MemtoReg),
.M_ReverseEndian (M_ReverseEndian),
.M_LLSC (M_LLSC),
.M_MemRead (M_MemRead),
.M_MemWrite (M_MemWrite),
.M_MemByte (M_MemByte),
.M_MemHalf (M_MemHalf),
.M_MemSignExtend (M_MemSignExtend),
.M_Left (M_Left),
.M_Right (M_Right),
.M_KernelMode (M_KernelMode),
.M_RestartPC (M_RestartPC),
.M_IsBDS (M_IsBDS),
.M_Trap (M_Trap),
.M_TrapCond (M_TrapCond),
.M_M_CanErr (M_M_CanErr),
.M_ALU_Result (M_ALUResult),
.M_ReadData2 (M_ReadData2_PR),
.M_RtRd (M_RtRd)
);
/*** Trap Detection Unit ***/
TrapDetect TrapDetect (
.Trap (M_Trap),
.TrapCond (M_TrapCond),
.ALUResult (M_ALUResult),
.EXC_Tr (M_EXC_Tr)
);
/*** MEM Write Data Mux ***/
Mux2 #(.WIDTH(32)) MWriteData_Mux (
.sel (M_WriteDataFwdSel),
.in0 (M_ReadData2_PR),
.in1 (WB_WriteData),
.out (M_WriteData_Pre)
);
/*** Data Memory Controller ***/
MemControl DataMem_Controller (
.clock (clock),
.reset (reset),
.DataIn (M_WriteData_Pre),
.Address (M_ALUResult),
.MReadData (DataMem_In),
.MemRead (M_MemRead),
.MemWrite (M_MemWrite),
.DataMem_Ack (DataMem_Ack),
.Byte (M_MemByte),
.Half (M_MemHalf),
.SignExtend (M_MemSignExtend),
.KernelMode (M_KernelMode),
.ReverseEndian (M_ReverseEndian),
.LLSC (M_LLSC),
.ERET (ID_Eret),
.Left (M_Left),
.Right (M_Right),
.M_Exception_Stall (M_Exception_Stall),
.IF_Stall (IF_Stall),
.DataOut (M_MemReadData),
.MWriteData (DataMem_Out),
.WriteEnable (DataMem_Write),
.ReadEnable (DataMem_Read),
.M_Stall (M_Stall_Controller),
.EXC_AdEL (M_EXC_AdEL),
.EXC_AdES (M_EXC_AdES)
);
/*** Memory -> Writeback Pipeline Stage ***/
MEMWB_Stage MEMWB (
.clock (clock),
.reset (reset),
.M_Flush (M_Exception_Flush),
.M_Stall (M_Stall),
.WB_Stall (WB_Stall),
.M_RegWrite (M_RegWrite),
.M_MemtoReg (M_MemtoReg),
.M_ReadData (M_MemReadData),
.M_ALU_Result (M_ALUResult),
.M_RtRd (M_RtRd),
.WB_RegWrite (WB_RegWrite),
.WB_MemtoReg (WB_MemtoReg),
.WB_ReadData (WB_ReadData),
.WB_ALU_Result (WB_ALUResult),
.WB_RtRd (WB_RtRd)
);
/*** WB MemtoReg Mux ***/
Mux2 #(.WIDTH(32)) WBMemtoReg_Mux (
.sel (WB_MemtoReg),
.in0 (WB_ALUResult),
.in1 (WB_ReadData),
.out (WB_WriteData)
);
endmodule