cvw/src/mdu/mul.sv
2023-03-01 13:05:02 -08:00

62 lines
2.4 KiB
Systemverilog

///////////////////////////////////////////
// mul.sv
//
// Written: David_Harris@hmc.edu 16 February 2021
// Modified:
//
// Purpose: Integer multiplication
//
// Documentation: RISC-V System on Chip Design Chapter 12 (Figure 12.18)
//
// A component of the CORE-V-WALLY configurable RISC-V project.
//
// 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.
////////////////////////////////////////////////////////////////////////////////////////////////
`include "wally-config.vh"
module mul(
input logic clk, reset,
input logic StallM, FlushM,
input logic [`XLEN-1:0] ForwardedSrcAE, ForwardedSrcBE, // source A and B from after Forwarding mux
input logic [2:0] Funct3E, // type of multiply
output logic [`XLEN*2-1:0] ProdM // double-widthproduct
);
logic [`XLEN*2-1:0] PP1E, PP2E, PP3E, PP4E; // partial products
logic [`XLEN*2-1:0] PP1M, PP2M, PP3M, PP4M; // registered partial proudcts
//////////////////////////////
// Execute Stage: Compute partial products
//////////////////////////////
// insert stuff here for lab 5
//////////////////////////////
// Memory Stage: Sum partial proudcts
//////////////////////////////
flopenrc #(`XLEN*2) PP1Reg(clk, reset, FlushM, ~StallM, PP1E, PP1M);
flopenrc #(`XLEN*2) PP2Reg(clk, reset, FlushM, ~StallM, PP2E, PP2M);
flopenrc #(`XLEN*2) PP3Reg(clk, reset, FlushM, ~StallM, PP3E, PP3M);
flopenrc #(`XLEN*2) PP4Reg(clk, reset, FlushM, ~StallM, PP4E, PP4M);
// add up partial products; this multi-input add implies CSAs and a final CPA
assign ProdM = PP1M + PP2M + PP3M + PP4M; //ForwardedSrcAE * ForwardedSrcBE;
endmodule