yosys/tests/iwls2005/aes_core/aes_rcon.v

97 lines
3.7 KiB
Verilog

/////////////////////////////////////////////////////////////////////
//// ////
//// AES RCON Block ////
//// ////
//// ////
//// Author: Rudolf Usselmann ////
//// rudi@asics.ws ////
//// ////
//// ////
//// Downloaded from: http://www.opencores.org/cores/aes_core/ ////
//// ////
/////////////////////////////////////////////////////////////////////
//// ////
//// Copyright (C) 2000-2002 Rudolf Usselmann ////
//// www.asics.ws ////
//// rudi@asics.ws ////
//// ////
//// This source file may be used and distributed without ////
//// restriction provided that this copyright statement is not ////
//// removed from the file and that any derivative work contains ////
//// the original copyright notice and the associated disclaimer.////
//// ////
//// THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY ////
//// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED ////
//// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS ////
//// FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL THE AUTHOR ////
//// 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. ////
//// ////
/////////////////////////////////////////////////////////////////////
// CVS Log
//
// $Id: aes_rcon.v,v 1.1.1.1 2002/11/09 11:22:38 rudi Exp $
//
// $Date: 2002/11/09 11:22:38 $
// $Revision: 1.1.1.1 $
// $Author: rudi $
// $Locker: $
// $State: Exp $
//
// Change History:
// $Log: aes_rcon.v,v $
// Revision 1.1.1.1 2002/11/09 11:22:38 rudi
// Initial Checkin
//
//
//
//
//
//
`include "timescale.v"
module aes_rcon(clk, kld, out);
input clk;
input kld;
output [31:0] out;
reg [31:0] out;
reg [3:0] rcnt;
wire [3:0] rcnt_next;
always @(posedge clk)
if(kld) out <= #1 32'h01_00_00_00;
else out <= #1 frcon(rcnt_next);
assign rcnt_next = rcnt + 4'h1;
always @(posedge clk)
if(kld) rcnt <= #1 4'h0;
else rcnt <= #1 rcnt_next;
function [31:0] frcon;
input [3:0] i;
case(i) // synopsys parallel_case
4'h0: frcon=32'h01_00_00_00;
4'h1: frcon=32'h02_00_00_00;
4'h2: frcon=32'h04_00_00_00;
4'h3: frcon=32'h08_00_00_00;
4'h4: frcon=32'h10_00_00_00;
4'h5: frcon=32'h20_00_00_00;
4'h6: frcon=32'h40_00_00_00;
4'h7: frcon=32'h80_00_00_00;
4'h8: frcon=32'h1b_00_00_00;
4'h9: frcon=32'h36_00_00_00;
default: frcon=32'h00_00_00_00;
endcase
endfunction
endmodule