cvw/pipelined/srt/testbench.sv
2022-02-14 18:37:46 +00:00

133 lines
2.9 KiB
Systemverilog

/////////////
// counter //
/////////////
module counter(input logic clk,
input logic req,
output logic done);
logic [5:0] count;
// This block of control logic sequences the divider
// through its iterations. You may modify it if you
// build a divider which completes in fewer iterations.
// You are not responsible for the (trivial) circuit
// design of the block.
always @(posedge clk)
begin
if (count == 54) done <= #1 1;
else if (done | req) done <= #1 0;
if (req) count <= #1 0;
else count <= #1 count+1;
end
endmodule
///////////
// clock //
///////////
module clock(clk);
output clk;
// Internal clk signal
logic clk;
endmodule
//////////
// testbench //
//////////
module testbench;
logic clk;
logic req;
logic done;
logic [51:0] a;
logic [51:0] b;
logic [51:0] r;
logic [54:0] rp, rm; // positive quotient digits
// Test parameters
parameter MEM_SIZE = 40000;
parameter MEM_WIDTH = 52+52+52;
`define memr 51:0
`define memb 103:52
`define mema 155:104
// Test logicisters
logic [MEM_WIDTH-1:0] Tests [0:MEM_SIZE]; // Space for input file
logic [MEM_WIDTH-1:0] Vec; // Verilog doesn't allow direct access to a
// bit field of an array
logic [51:0] correctr, nextr, diffn, diffp;
integer testnum, errors;
// Divider
srt #(52) srt(.clk, .Start(req),
.Stall(1'b0), .Flush(1'b0),
.SrcXFrac(a), .SrcYFrac(b),
.SrcA('0), .SrcB('0), .Fmt(2'b00),
.W64(1'b0), .Signed(1'b0), .Int(1'b0), .Sqrt(1'b0),
.Quot(r), .Rem(), .Flags());
// Counter
counter counter(clk, req, done);
initial
forever
begin
clk = 1; #17;
clk = 0; #16;
end
// Read test vectors from disk
initial
begin
testnum = 0;
errors = 0;
$readmemh ("testvectors", Tests);
Vec = Tests[testnum];
a = Vec[`mema];
b = Vec[`memb];
nextr = Vec[`memr];
req <= #5 1;
end
// Apply directed test vectors read from file.
always @(posedge clk)
begin
if (done)
begin
req <= #5 1;
diffp = correctr - r;
diffn = r - correctr;
if (($signed(diffn) > 1) | ($signed(diffp) > 1)) // check if accurate to 1 ulp
begin
errors = errors+1;
$display("result was %h, should be %h %h %h\n", r, correctr, diffn, diffp);
$display("failed\n");
$stop;
end
if (a === 52'hxxxxxxxxxxxxx)
begin
$display("%d Tests completed successfully", testnum);
$stop;
end
end
if (req)
begin
req <= #5 0;
correctr = nextr;
testnum = testnum+1;
Vec = Tests[testnum];
$display("a = %h b = %h",a,b);
a = Vec[`mema];
b = Vec[`memb];
nextr = Vec[`memr];
end
end
endmodule