Initial commit of base point multiplier core for ECDSA curve P-256.

1 files changed, 174 insertions, 0 deletions

diff --git a/bench/tb_lowlevel_subtractor32.v b/bench/tb_lowlevel_subtractor32.v
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+++ b/bench/tb_lowlevel_subtractor32.v
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+//------------------------------------------------------------------------------

+//

+// tb_lowlevel_subtractor32.v

+// -----------------------------------------------------------------------------

+// Testbench for 32-bit subtractor.

+//

+// Authors: Pavel Shatov

+//

+// Copyright (c) 2015-2016, NORDUnet A/S

+//

+// Redistribution and use in source and binary forms, with or without

+// modification, are permitted provided that the following conditions are met:

+//

+// - Redistributions of source code must retain the above copyright notice,

+//   this list of conditions and the following disclaimer.

+//

+// - Redistributions in binary form must reproduce the above copyright notice,

+//   this list of conditions and the following disclaimer in the documentation

+//   and/or other materials provided with the distribution.

+//

+// - Neither the name of the NORDUnet nor the names of its contributors may be

+//   used to endorse or promote products derived from this software without

+//   specific prior written permission.

+//

+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"

+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

+// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE

+// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR

+// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF

+// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS

+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN

+// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)

+// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE

+// POSSIBILITY OF SUCH DAMAGE.

+//

+//------------------------------------------------------------------------------

+

+

+//------------------------------------------------------------------------------

+`timescale 1ns / 1ps

+//------------------------------------------------------------------------------

+

+module tb_lowlevel_subtractor32;

+

+		//

+		// Inputs

+		//

+	reg				clk;

+	reg	[31: 0]	a;

+	reg	[31: 0]	b;

+	reg				b_in;

+

+		//

+		// Outputs

+		//

+	wire	[31: 0]	d;

+	wire				b_out;

+

+		//

+		// Test Vectors {a, b, b_in}

+		//

+	wire	[64: 0]	vec_0		= {32'h00000000, 32'h00000000, 1'b0};	// all zeroes, no borrow

+	wire	[64: 0]	vec_1		= {32'h00000000, 32'h00000000, 1'b1};	// all zeroes with borrow

+	wire	[64: 0]	vec_2		= {32'h00000000, 32'hFFFFFFFF, 1'b0};	// zeroes and ones, no borrow

+	wire	[64: 0]	vec_3		= {32'h00000000, 32'hFFFFFFFF, 1'b1};	// zeroes and ones with borrow

+	wire	[64: 0]	vec_4		= {32'hFFFFFFFF, 32'h00000000, 1'b0};	// ones and zeroes, no borrow

+	wire	[64: 0]	vec_5		= {32'hFFFFFFFF, 32'h00000000, 1'b1};	// ones and zeroes with borrow

+	wire	[64: 0]	vec_6		= {32'hFFFFFFFF, 32'hFFFFFFFF, 1'b0};	// all ones, no borrow

+	wire	[64: 0]	vec_7		= {32'hFFFFFFFF, 32'hFFFFFFFF, 1'b1};	// all ones with borrow

+	

+	wire	[64: 0]	vec_8		= {32'hd898c296, 32'h37bf51f5, 1'b0};	// random values, no borrow

+	wire	[64: 0]	vec_9		= {32'hf4a13945, 32'hcbb64068, 1'b0};	// random values, no borrow

+	wire	[64: 0]	vec_10	= {32'h2deb33a0, 32'h6b315ece, 1'b0};	// random values, no borrow

+	wire	[64: 0]	vec_11	= {32'h77037d81, 32'h2bce3357, 1'b0};	// random values, no borrow

+	wire	[64: 0]	vec_12	= {32'h63a440f2, 32'h7c0f9e16, 1'b1};	// random values with borrow

+	wire	[64: 0]	vec_13	= {32'hf8bce6e5, 32'h8ee7eb4a, 1'b1};	// random values with borrow

+	wire	[64: 0]	vec_14	= {32'he12c4247, 32'hfe1a7f9b, 1'b1};	// random values with borrow

+	wire	[64: 0]	vec_15	= {32'h6b17d1f2, 32'h4fe342e2, 1'b1};	// random values with borrow

+

+

+		//

+		// UUT

+		//

+	subtractor32_wrapper uut

+	(

+		.clk		(clk),

+		.a			(a),

+		.b			(b),

+		.d			(d),

+		.b_in		(b_in),

+		.b_out	(b_out)

+	);

+

+	

+		//

+		// Testbench Routine

+		//

+	reg ok = 1;

+	initial begin

+		//

+		clk = 0;

+		//

+		#100;

+		//

+		test_subtractor32(vec_0);

+		test_subtractor32(vec_1);

+		test_subtractor32(vec_2);

+		test_subtractor32(vec_3);

+		test_subtractor32(vec_4);

+		test_subtractor32(vec_5);

+		test_subtractor32(vec_6);

+		test_subtractor32(vec_7);

+		//

+		test_subtractor32(vec_8);

+		test_subtractor32(vec_9);

+		test_subtractor32(vec_10);

+		test_subtractor32(vec_11);

+		test_subtractor32(vec_12);

+		test_subtractor32(vec_13);

+		test_subtractor32(vec_14);

+		test_subtractor32(vec_15);

+		//

+		if (ok)	$display("tb_lowlevel_subtractor32: SUCCESS");

+		else		$display("tb_lowlevel_subtractor32: FAILURE");

+		//

+		$finish;

+		//

+	end

+      

+		

+		//

+		// Test Routine

+		//

+	reg	[31: 0]	dd;		// reference value of difference

+	reg				bb;		// reference value of borrow

+	reg				dd_ok;	// result matches reference value

+	

+	task test_subtractor32;

+

+		input	[64: 0] vec;

+

+		begin

+		

+				/* break down test vector */

+			a		= vec[64:33];

+			b		= vec[32: 1];

+			b_in	= vec[ 0: 0];

+

+				/* calculate reference values */

+			{bb, dd} = {1'b0, a} - {1'b0, b} - {32'd0, b_in};

+

+				/* send one clock tick */

+			#10 clk = 1;

+			#10 clk = 0;

+			

+				/* check outputs */

+			dd_ok = (d == dd) && (b_out == bb);

+

+				/* display results */

+			$display("test_subtractor32(): 0x%08X - (0x%08X + %01d) = {%01d, 0x%08X} [%0s]", a, b, b_in, b_out, d, dd_ok ? "OK" : "ERROR");

+			

+				/* update global flag */

+			ok = ok && dd_ok;

+			

+		end

+		

+	endtask

+		

+endmodule

+

+//------------------------------------------------------------------------------

+// End-of-File

+//------------------------------------------------------------------------------