picorv32/scripts/csmith/testbench.v

101 lines
2.1 KiB
Verilog

`timescale 1 ns / 1 ps
module testbench (
`ifdef VERILATOR
input clk
`endif
);
`ifndef VERILATOR
reg clk = 1;
always #5 clk = ~clk;
`endif
reg resetn = 0;
integer resetn_cnt = 0;
wire trap;
initial begin
// $dumpfile("testbench.vcd");
// $dumpvars(0, testbench);
end
always @(posedge clk) begin
if (resetn_cnt < 100)
resetn_cnt <= resetn_cnt + 1;
else
resetn <= 1;
end
wire mem_valid;
wire mem_instr;
wire mem_ready;
wire [31:0] mem_addr;
wire [31:0] mem_wdata;
wire [3:0] mem_wstrb;
wire [31:0] mem_rdata;
reg [31:0] x32 = 314159265;
reg [31:0] next_x32;
always @(posedge clk) begin
if (resetn) begin
next_x32 = x32;
next_x32 = next_x32 ^ (next_x32 << 13);
next_x32 = next_x32 ^ (next_x32 >> 17);
next_x32 = next_x32 ^ (next_x32 << 5);
x32 <= next_x32;
end
end
picorv32 #(
.COMPRESSED_ISA(1),
.ENABLE_MUL(1),
.ENABLE_DIV(1)
) uut (
.clk (clk ),
.resetn (resetn ),
.trap (trap ),
.mem_valid (mem_valid ),
.mem_instr (mem_instr ),
.mem_ready (mem_ready ),
.mem_addr (mem_addr ),
.mem_wdata (mem_wdata ),
.mem_wstrb (mem_wstrb ),
.mem_rdata (mem_rdata )
);
reg [7:0] memory [0:4*1024*1024-1];
initial $readmemh("test.hex", memory);
assign mem_ready = x32[0] && mem_valid;
assign mem_rdata[ 7: 0] = memory[mem_addr + 0];
assign mem_rdata[15: 8] = memory[mem_addr + 1];
assign mem_rdata[23:16] = memory[mem_addr + 2];
assign mem_rdata[31:24] = memory[mem_addr + 3];
always @(posedge clk) begin
if (mem_valid && mem_ready) begin
if (mem_wstrb && mem_addr == 'h10000000) begin
$write("%c", mem_wdata[ 7: 0]);
`ifndef VERILATOR
$fflush;
`endif
end else begin
if (mem_wstrb[0]) memory[mem_addr + 0] <= mem_wdata[ 7: 0];
if (mem_wstrb[1]) memory[mem_addr + 1] <= mem_wdata[15: 8];
if (mem_wstrb[2]) memory[mem_addr + 2] <= mem_wdata[23:16];
if (mem_wstrb[3]) memory[mem_addr + 3] <= mem_wdata[31:24];
end
end
end
always @(posedge clk) begin
if (resetn && trap) begin
// repeat (10) @(posedge clk);
// $display("TRAP");
$finish;
end
end
endmodule