/////////////////////////////////////////// // ieu.sv // // Written: David_Harris@hmc.edu 9 January 2021 // Modified: // // Purpose: Integer Execution Unit: datapath and controller // // Documentation: RISC-V System on Chip Design // // A component of the CORE-V-WALLY configurable RISC-V project. // https://github.com/openhwgroup/cvw // // Copyright (C) 2021-23 Harvey Mudd College & Oklahoma State University // // SPDX-License-Identifier: Apache-2.0 WITH SHL-2.1 // // Licensed under the Solderpad Hardware License v 2.1 (the “License”); you may not use this file // except in compliance with the License, or, at your option, the Apache License version 2.0. You // may obtain a copy of the License at // // https://solderpad.org/licenses/SHL-2.1/ // // Unless required by applicable law or agreed to in writing, any work distributed under the // License is distributed on an “AS IS” BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, // either express or implied. See the License for the specific language governing permissions // and limitations under the License. //////////////////////////////////////////////////////////////////////////////////////////////// module ieu import cvw::*; #(parameter cvw_t P) ( input logic clk, reset, // Decode stage signals input logic [31:0] InstrD, // Instruction input logic [1:0] STATUS_FS, // is FPU enabled? input logic [3:0] ENVCFG_CBE, // Cache block operation enables input logic IllegalIEUFPUInstrD, // Illegal instruction output logic IllegalBaseInstrD, // Illegal I-type instruction, or illegal RV32 access to upper 16 registers // Execute stage signals input logic [P.XLEN-1:0] PCE, // PC input logic [P.XLEN-1:0] PCLinkE, // PC + 4 output logic PCSrcE, // Select next PC (between PC+4 and IEUAdrE) input logic FWriteIntE, FCvtIntE, // FPU writes to integer register file, FPU converts float to int output logic [P.XLEN-1:0] IEUAdrE, // Memory address output logic IntDivE, W64E, // Integer divide, RV64 W-type instruction output logic [2:0] Funct3E, // Funct3 instruction field output logic [P.XLEN-1:0] ForwardedSrcAE, ForwardedSrcBE, // ALU src inputs before the mux choosing between them and PCE to put in srcA/B output logic [4:0] RdE, // Destination register output logic MDUActiveE, // Mul/Div instruction being executed output logic [3:0] CMOpM, // 1: cbo.inval; 2: cbo.flush; 4: cbo.clean; 8: cbo.zero output logic IFUPrefetchE, // instruction prefetch output logic LSUPrefetchM, // datata prefetch // Memory stage signals input logic SquashSCW, // Squash store conditional, from LSU output logic [1:0] MemRWE, // Read/write control goes to LSU output logic [1:0] MemRWM, // Read/write control goes to LSU output logic [1:0] AtomicM, // Atomic control goes to LSU output logic [P.XLEN-1:0] WriteDataM, // Write data to LSU output logic [2:0] Funct3M, // Funct3 (size and signedness) to LSU output logic [P.XLEN-1:0] SrcAM, // ALU SrcA to Privileged unit and FPU output logic [4:0] RdM, // Destination register input logic [P.XLEN-1:0] FIntResM, // Integer result from FPU (fmv, fclass, fcmp) output logic InvalidateICacheM, FlushDCacheM, // Invalidate I$, flush D$ output logic InstrValidD, InstrValidE, InstrValidM, // Instruction is valid output logic BranchD, BranchE, output logic JumpD, JumpE, // Writeback stage signals input logic [P.XLEN-1:0] FIntDivResultW, // Integer divide result from FPU fdivsqrt) input logic [P.XLEN-1:0] CSRReadValW, // CSR read value, input logic [P.XLEN-1:0] MDUResultW, // multiply/divide unit result input logic [P.XLEN-1:0] FCvtIntResW, // FPU's float to int conversion result input logic FCvtIntW, // FPU converts float to int output logic [4:0] RdW, // Destination register input logic [P.XLEN-1:0] ReadDataW, // LSU's read data // Hazard unit signals input logic StallD, StallE, StallM, StallW, // Stall signals from hazard unit input logic FlushD, FlushE, FlushM, FlushW, // Flush signals output logic StructuralStallD, // IEU detects structural hazard in Decode stage output logic LoadStallD, // Structural stalls for load, sent to performance counters output logic StoreStallD, // load after store hazard output logic CSRReadM, CSRWriteM, PrivilegedM,// CSR read, CSR write, is privileged instruction output logic CSRWriteFenceM // CSR write or fence instruction needs to flush subsequent instructions ); logic [2:0] ImmSrcD; // Select type of immediate extension logic [1:0] FlagsE; // Comparison flags ({eq, lt}) logic ALUSrcAE, ALUSrcBE; // ALU source operands logic [2:0] ResultSrcW; // Selects result in Writeback stage logic ALUResultSrcE; // Selects ALU result to pass on to Memory stage logic [2:0] ALUSelectE; // ALU select mux signal logic FWriteIntM; // FPU writing to integer register file logic IntDivW; // Integer divide instruction logic [3:0] BSelectE; // Indicates if ZBA_ZBB_ZBC_ZBS instruction in one-hot encoding logic [3:0] ZBBSelectE; // ZBB Result Select Signal in Execute Stage logic [2:0] BALUControlE; // ALU Control signals for B instructions in Execute Stage logic SubArithE; // Subtraction or arithmetic shift logic UW64E; // .uw-type instruction logic [6:0] Funct7E; // Forwarding signals logic [4:0] Rs1D, Rs2D; logic [4:0] Rs2E; // Source registers logic [1:0] ForwardAE, ForwardBE; // Select signals for forwarding multiplexers logic RegWriteW; // Register will be written in Writeback stage logic BranchSignedE; // Branch does signed comparison on operands logic BMUActiveE; // Bit manipulation instruction being executed logic [1:0] CZeroE; // {czero.nez, czero.eqz} instructions active controller #(P) c( .clk, .reset, .StallD, .FlushD, .InstrD, .STATUS_FS, .ENVCFG_CBE, .ImmSrcD, .IllegalIEUFPUInstrD, .IllegalBaseInstrD, .StructuralStallD, .LoadStallD, .StoreStallD, .Rs1D, .Rs2D, .Rs2E, .StallE, .FlushE, .FlagsE, .FWriteIntE, .PCSrcE, .ALUSrcAE, .ALUSrcBE, .ALUResultSrcE, .ALUSelectE, .Funct3E, .Funct7E, .IntDivE, .W64E, .UW64E, .SubArithE, .BranchD, .BranchE, .JumpD, .JumpE, .BranchSignedE, .BSelectE, .ZBBSelectE, .BALUControlE, .BMUActiveE, .CZeroE, .MDUActiveE, .FCvtIntE, .ForwardAE, .ForwardBE, .CMOpM, .IFUPrefetchE, .LSUPrefetchM, .StallM, .FlushM, .MemRWE, .MemRWM, .CSRReadM, .CSRWriteM, .PrivilegedM, .AtomicM, .Funct3M, .FlushDCacheM, .InstrValidM, .InstrValidE, .InstrValidD, .FWriteIntM, .StallW, .FlushW, .RegWriteW, .IntDivW, .ResultSrcW, .CSRWriteFenceM, .InvalidateICacheM, .RdW, .RdE, .RdM); datapath #(P) dp( .clk, .reset, .ImmSrcD, .InstrD, .Rs1D, .Rs2D, .Rs2E, .StallE, .FlushE, .ForwardAE, .ForwardBE, .W64E, .UW64E, .SubArithE, .Funct3E, .Funct7E, .ALUSrcAE, .ALUSrcBE, .ALUResultSrcE, .ALUSelectE, .JumpE, .BranchSignedE, .PCE, .PCLinkE, .FlagsE, .IEUAdrE, .ForwardedSrcAE, .ForwardedSrcBE, .BSelectE, .ZBBSelectE, .BALUControlE, .BMUActiveE, .CZeroE, .StallM, .FlushM, .FWriteIntM, .FIntResM, .SrcAM, .WriteDataM, .FCvtIntW, .StallW, .FlushW, .RegWriteW, .IntDivW, .SquashSCW, .ResultSrcW, .ReadDataW, .FCvtIntResW, .CSRReadValW, .MDUResultW, .FIntDivResultW, .RdW); endmodule