//////////////////////////////////////////////////////////////////////
////                                                              ////
////  AES top file                                                ////
////                                                              ////
////  This file is part of the SystemC AES                        ////
////                                                              ////
////  Description:                                                ////
////  AES top                                                     ////
////                                                              ////
////  Generated automatically using SystemC to Verilog translator ////
////                                                              ////
////  To Do:                                                      ////
////   - done                                                     ////
////                                                              ////
////  Author(s):                                                  ////
////      - Javier Castillo, jcastilo@opencores.org               ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
////                                                              ////
//// Copyright (C) 2000 Authors and OPENCORES.ORG                 ////
////                                                              ////
//// 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 source file is free software; you can redistribute it   ////
//// and/or modify it under the terms of the GNU Lesser General   ////
//// Public License as published by the Free Software Foundation; ////
//// either version 2.1 of the License, or (at your option) any   ////
//// later version.                                               ////
////                                                              ////
//// This source is distributed in the hope that it will be       ////
//// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
//// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
//// PURPOSE.  See the GNU Lesser General Public License for more ////
//// details.                                                     ////
////                                                              ////
//// You should have received a copy of the GNU Lesser General    ////
//// Public License along with this source; if not, download it   ////
//// from http://www.opencores.org/lgpl.shtml                     ////
////                                                              ////
//////////////////////////////////////////////////////////////////////
//
// CVS Revision History
//
// $Log: aes.v,v $
// Revision 1.1.1.1  2004/07/05 09:46:23  jcastillo
// First import
//

module aes(clk,reset,load_i,decrypt_i,data_i,key_i,ready_o,data_o);
input clk;
input reset;
input load_i;
input decrypt_i;
input [127:0] data_i;
input [127:0] key_i;
output ready_o;
output [127:0] data_o;

reg ready_o;
reg [127:0] data_o;

reg next_ready_o;
reg keysched_start_i;
reg [3:0] keysched_round_i;
reg [127:0] keysched_last_key_i;
wire [127:0] keysched_new_key_o;

wire keysched_ready_o;

wire keysched_sbox_access_o;

wire [7:0] keysched_sbox_data_o;

wire keysched_sbox_decrypt_o;

reg mixcol_start_i;
reg [127:0] mixcol_data_i;
wire mixcol_ready_o;

wire [127:0] mixcol_data_o;

reg subbytes_start_i;
reg [127:0] subbytes_data_i;
wire subbytes_ready_o;

wire [127:0] subbytes_data_o;

wire [7:0] subbytes_sbox_data_o;

wire subbytes_sbox_decrypt_o;

wire [7:0] sbox_data_o;

reg [7:0] sbox_data_i;
reg sbox_decrypt_i;
reg state;
reg next_state;
reg [3:0] round;
reg [3:0] next_round;
reg [127:0] addroundkey_data_o;
reg [127:0] next_addroundkey_data_reg;
reg [127:0] addroundkey_data_reg;
reg [127:0] addroundkey_data_i;
reg addroundkey_ready_o;
reg next_addroundkey_ready_o;
reg addroundkey_start_i;
reg next_addroundkey_start_i;
reg [3:0] addroundkey_round;
reg [3:0] next_addroundkey_round;
reg first_round_reg;
reg next_first_round_reg;

sbox sbox1 (.clk(clk), .reset(reset), .data_i(sbox_data_i), .decrypt_i(sbox_decrypt_i), .data_o(sbox_data_o));
subbytes sub1 (.clk(clk), .reset(reset), .start_i(subbytes_start_i), .decrypt_i(decrypt_i), .data_i(subbytes_data_i), .ready_o(subbytes_ready_o), .data_o(subbytes_data_o), .sbox_data_o(subbytes_sbox_data_o), .sbox_data_i(sbox_data_o), .sbox_decrypt_o(subbytes_sbox_decrypt_o));
mixcolum mix1 (.clk(clk), .reset(reset), .decrypt_i(decrypt_i), .start_i(mixcol_start_i), .data_i(mixcol_data_i), .ready_o(mixcol_ready_o), .data_o(mixcol_data_o));
keysched ks1 (.clk(clk), .reset(reset), .start_i(keysched_start_i), .round_i(keysched_round_i), .last_key_i(keysched_last_key_i), .new_key_o(keysched_new_key_o), .ready_o(keysched_ready_o), .sbox_access_o(keysched_sbox_access_o), .sbox_data_o(keysched_sbox_data_o), .sbox_data_i(sbox_data_o), .sbox_decrypt_o(keysched_sbox_decrypt_o));

//registers:
always @(posedge clk or negedge reset)

begin

	if(!reset)
begin

		state = (0);
		ready_o = (0);
		round = (0);
        addroundkey_round = (0);
		addroundkey_data_reg = (0);
		addroundkey_ready_o = (0);
		addroundkey_start_i = (0);
		first_round_reg = (0);
	
end
else
begin

		state = (next_state);
		ready_o = (next_ready_o);
		round = (next_round);
		addroundkey_round = (next_addroundkey_round);
		addroundkey_data_reg = (next_addroundkey_data_reg);
		addroundkey_ready_o = (next_addroundkey_ready_o);
		first_round_reg = (next_first_round_reg);
		addroundkey_start_i = (next_addroundkey_start_i);
	
end


end
//control:
always @(  state or   round or   addroundkey_data_o or   data_i or   load_i or   decrypt_i or   addroundkey_ready_o or   mixcol_ready_o or   subbytes_ready_o or   subbytes_data_o or   mixcol_data_o or   first_round_reg)

begin

	
	next_state = (state);
	next_round = (round);
	data_o = (addroundkey_data_o);
	next_ready_o = (0);
	
	//Tokeyschedulemodule
				
	next_first_round_reg = (0);
		
	
	subbytes_data_i = (0);	
	mixcol_data_i = (0);
	addroundkey_data_i = (0);
	next_addroundkey_start_i = (first_round_reg);
    mixcol_start_i = ((addroundkey_ready_o&decrypt_i&round!=10)|(subbytes_ready_o&!decrypt_i));
    subbytes_start_i = ((addroundkey_ready_o&!decrypt_i)|(mixcol_ready_o&decrypt_i)|(addroundkey_ready_o&decrypt_i&round==10));	
		
    if(decrypt_i&&round!=10)
    begin
 	   addroundkey_data_i = (subbytes_data_o);
  	   subbytes_data_i = (mixcol_data_o);
       mixcol_data_i = (addroundkey_data_o);
    end
    else if(!decrypt_i&&round!=0)
    begin
 	   addroundkey_data_i = (mixcol_data_o);	
 	   subbytes_data_i = (addroundkey_data_o);
       mixcol_data_i = (subbytes_data_o);
    end
    else
    begin
	   mixcol_data_i = (subbytes_data_o);
  	   subbytes_data_i = (addroundkey_data_o);
	   addroundkey_data_i = (data_i);
    end


    case(state)
		
		0:
        begin
		 if(load_i)
         begin
		 	next_state = (1);
			if(decrypt_i)
				next_round = (10);
			else
				next_round = (0);
		  	    next_first_round_reg = (1);
			end
		end
			
		1:
        begin
	
		//Counter	
		if(!decrypt_i&&mixcol_ready_o)
        begin
 		  next_addroundkey_start_i = (1);
		  addroundkey_data_i = (mixcol_data_o);	
		  next_round = (round+1);
		end
        else if(decrypt_i&&subbytes_ready_o)
        begin
 		  next_addroundkey_start_i = (1);
		  addroundkey_data_i = (subbytes_data_o);
		  next_round = (round-1);
		end

		//Output
		if((round==9&&!decrypt_i)||(round==0&&decrypt_i))
        begin
		  next_addroundkey_start_i = (0);
		  mixcol_start_i = (0);
		if(subbytes_ready_o)
        begin
		  addroundkey_data_i = (subbytes_data_o);
		  next_addroundkey_start_i = (1);
		  next_round = (round+1);
        end
        end

		if((round==10&&!decrypt_i)||(round==0&&decrypt_i))
        begin
		  addroundkey_data_i = (subbytes_data_o);
		  subbytes_start_i = (0);
		if(addroundkey_ready_o)
        begin
		  next_ready_o = (1);
		  next_state = (0);
		  next_addroundkey_start_i = (0);
		  next_round = (0);
		end
	
		end

			
		end
			
		default:
begin
			next_state = (0);
			end
	endcase


end
//addroundkey:
reg[127:0] data_var,round_data_var,round_key_var;
always @(  addroundkey_data_i or   addroundkey_start_i or   addroundkey_data_reg or   addroundkey_round or   keysched_new_key_o or   keysched_ready_o or   key_i or   round)

begin

	
	round_data_var=addroundkey_data_reg;
	next_addroundkey_data_reg = (addroundkey_data_reg);
next_addroundkey_ready_o = (0);
	next_addroundkey_round = (addroundkey_round);
	addroundkey_data_o = (addroundkey_data_reg);
	
	if(addroundkey_round==1||addroundkey_round==0)
	keysched_last_key_i = (key_i);
else
	keysched_last_key_i = (keysched_new_key_o);
	
	keysched_start_i = (0);
	
	keysched_round_i = (addroundkey_round);
		
	if(round==0&&addroundkey_start_i)
begin

	//Taketheinputandxorthemwithdataifround==0;
	data_var=addroundkey_data_i;	
	round_key_var=key_i;
	round_data_var=round_key_var^data_var;
	next_addroundkey_data_reg = (round_data_var);
next_addroundkey_ready_o = (1);
	
end
else if(addroundkey_start_i&&round!=0)
begin

	keysched_last_key_i = (key_i);	
	keysched_start_i = (1);
	keysched_round_i = (1);
	next_addroundkey_round = (1);
	
end
else if(addroundkey_round!=round&&keysched_ready_o)
begin

next_addroundkey_round = (addroundkey_round+1);
	keysched_last_key_i = (keysched_new_key_o);
	keysched_start_i = (1);
	keysched_round_i = (addroundkey_round+1);
	
end
else if(addroundkey_round==round&&keysched_ready_o)
begin

	data_var=addroundkey_data_i;	
	round_key_var=keysched_new_key_o;
	round_data_var=round_key_var^data_var;
	next_addroundkey_data_reg = (round_data_var);
next_addroundkey_ready_o = (1);
	next_addroundkey_round = (0);

end
		

end
//sbox_muxes:
always @(  keysched_sbox_access_o or   keysched_sbox_decrypt_o or   keysched_sbox_data_o or   subbytes_sbox_decrypt_o or   subbytes_sbox_data_o)

begin

	
	if(keysched_sbox_access_o)
begin

		sbox_decrypt_i = (keysched_sbox_decrypt_o);
		sbox_data_i = (keysched_sbox_data_o);
	
end
else
begin

		sbox_decrypt_i = (subbytes_sbox_decrypt_o);
sbox_data_i = (subbytes_sbox_data_o);
	
end


end

endmodule