cvw/testbench/common/ramxdetector.sv

48 lines
1.9 KiB
Systemverilog

///////////////////////////////////////////
// ramxdetector.sv
//
// Written: David_Harris@hmc.edu
// Modified: 2 July 2023
//
// Purpose: Detects if the processor is attempting to read unitialized RAM
//
// A component of the Wally configurable RISC-V project.
//
// Copyright (C) 2021 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 ramxdetector #(parameter XLEN, LLEN) (
input logic clk,
input logic MemReadM,
input logic LSULoadAccessFaultM,
input logic [LLEN-1:0] ReadDataM,
input logic [XLEN-1:0] PCM,
input logic [31:0] InstrM,
input logic [XLEN-1:0] IEUAdrM,
input string InstrMName
);
always_ff @(posedge clk)
/* verilator lint_off WIDTHXZEXPAND */
if (MemReadM & ~LSULoadAccessFaultM & (ReadDataM === 'bx)) begin
/* verilator lint_on WIDTHXZEXPAND */
$display("WARNING: Attempting to read from unitialized RAM. Processor may go haywire if it uses x value. But this is normal in WALLY-mmu tests.");
$display(" PCM = %x InstrM = %x (%s), IEUAdrM = %x", PCM, InstrM, InstrMName, IEUAdrM);
//$stop;
end
endmodule