cvw/pipelined/src/cache/subcachelineread.sv
2023-01-11 15:15:08 -08:00

53 lines
2.2 KiB
Systemverilog

///////////////////////////////////////////
// subcachelineread
//
// Written: Ross Thompson ross1728@gmail.com February 04, 2022
// Muxes the cache line downto the word size. Also include possilbe save/restore registers/muxes.
//
// Purpose: Controller for the dcache fsm
//
// 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 subcachelineread #(parameter LINELEN, WORDLEN, MUXINTERVAL)(
input logic [$clog2(LINELEN/8) - $clog2(MUXINTERVAL/8) - 1 : 0] PAdr,
input logic [LINELEN-1:0] ReadDataLine,
output logic [WORDLEN-1:0] ReadDataWord);
localparam WORDSPERLINE = LINELEN/MUXINTERVAL;
// pad is for icache. Muxing extends over the cacheline boundary.
localparam PADLEN = WORDLEN-MUXINTERVAL;
logic [LINELEN+(WORDLEN-MUXINTERVAL)-1:0] ReadDataLinePad;
logic [WORDLEN-1:0] ReadDataLineSets [(LINELEN/MUXINTERVAL)-1:0];
if (PADLEN > 0) begin
logic [PADLEN-1:0] Pad;
assign Pad = '0;
assign ReadDataLinePad = {Pad, ReadDataLine};
end else assign ReadDataLinePad = ReadDataLine;
genvar index;
for (index = 0; index < WORDSPERLINE; index++) begin:readdatalinesetsmux
assign ReadDataLineSets[index] = ReadDataLinePad[(index*MUXINTERVAL)+WORDLEN-1: (index*MUXINTERVAL)];
end
// variable input mux
assign ReadDataWord = ReadDataLineSets[PAdr];
endmodule