// ========== Copyright Header Begin ==========================================
// OpenSPARC T2 Processor File: pcs_rx_disparity.v
// Copyright (C) 1995-2007 Sun Microsystems, Inc. All Rights Reserved
// 4150 Network Circle, Santa Clara, California 95054, U.S.A.
// * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; version 2 of the License.
// This program 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 General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with this program; if not, write to the Free Software
// Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
// For the avoidance of doubt, and except that if any non-GPL license
// choice is available it will apply instead, Sun elects to use only
// the General Public License version 2 (GPLv2) at this time for any
// software where a choice of GPL license versions is made
// available with the language indicating that GPLv2 or any later version
// may be used, or where a choice of which version of the GPL is applied is
// otherwise unspecified.
// Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
// CA 95054 USA or visit www.sun.com if you need additional information or
// ========== Copyright Header End ============================================
// @(#)pcs_rx_disparity.v 1.1G
/**********************************************************************/
/* Project Name : CASSINI */
/* Module Name : PCS Running Disparity Calculator */
/* Description : Calculates new running disparity based on */
/* disparity for both most significant 6 bits and */
/* least significant 4 bits. The running disparity */
/* of the most significant 6 bits is called new_RD. */
/* The final running disparity for all 10 bits is */
/* Assumptions : none. */
/* Parent module : pcs_decoder.v */
/* Child modules : none. */
/* Author Name : Linda Chen */
/* Date Created : 10/21/96 */
/* Copyright (c) 1994, Sun Microsystems, Inc. */
/* Sun Proprietary and Confidential */
/* Modifications : none yet */
/* Synthesis Notes : none yet */
/**********************************************************************/
module pcs_rx_disparity (data, RDreg, // inputs
input [9:0] data; // 8b10b encoded data
input RDreg; // current running disparity
output newRD, // mid character running disparity
RD; // final value for running disparity
wire noneof6, oneof6, twoof6, threeof6, fourof6, fiveof6, sixof6;
//no. of 1#s in data[9:4]
wire noneof4, oneof4, twoof4, threeof4, fourof4;
//no. of 1#s in data[3:0]
assign noneof4 = ~(data[0] | data[1] | data[2] | data[3]),
fourof4 = data[0] & data[1] & data[2] & data[3],
threeof4 = ((data[0]^data[1]) & (~(data[2]^data[3]) &
(data[2]&data[3]))) | ((data[2]^data[3]) &
(~(data[0]^data[1]) & (data[0]&data[1]))),
oneof4 = ((~data[0]^~data[1]) & (~(~data[2]^~data[3]) &
(~data[2]&~data[3]))) | ((~data[2]^~data[3]) &
(~(~data[0]^~data[1]) & (~data[0]&~data[1]))),
twoof4 = ((data[0]^data[1]) & (data[2]^data[3])) |
((data[0]&data[1]) ^ (data[2]&data[3])),
noneof6 = ~(data[4] | data[5] | data[6] | data[7] |
sixof6 = data[4] & data[5] & data[6] & data[7] & data[8] &
fiveof6 = ( (((data[4]^data[5]) & (~(data[6]^data[7]) &
(data[6]&data[7]))) | ((data[6]^data[7]) &
(~(data[4]^data[5]) & (data[4]&data[5])))) &
(data[8] & data[9]) ) | ((data[4] & data[5] &
data[6] & data[7]) & (data[8] ^ data[9])),
oneof6 = ( (((~data[4]^~data[5]) & (~(~data[6]^~data[7]) &
(~data[6]&~data[7]))) | ((~data[6]^~data[7]) &
(~(~data[4]^~data[5]) & (~data[4]&~data[5]))))
& (~data[8] & ~data[9]) ) | ((~data[4] & ~data[5] &
~data[6] & ~data[7]) & (~data[8] ^ ~data[9])),
fourof6 = ( (((data[4]^data[5]) & (data[6]^data[7])) |
((data[4]&data[5]) ^ (data[6]&data[7]))) &
(data[8] & data[9]) ) | ( (((data[4]^data[5]) &
(~(data[6]^data[7]) & (data[6]&data[7]))) |
((data[6]^data[7]) & (~(data[4]^data[5]) &
(data[4]&data[5])))) & (data[8] ^ data[9]) ) |
( (data[4] & data[5] & data[6] & data[7]) &
twoof6 = ( (((~data[4]^~data[5]) & (~data[6]^~data[7])) |
((~data[4]&~data[5]) ^ (~data[6]&~data[7]))) &
(~data[8] & ~data[9]) ) | ( (((~data[4]^~data[5]) &
(~(~data[6]^~data[7]) & (~data[6]&~data[7])))
| ((~data[6]^~data[7]) & (~(~data[4]^~data[5]) &
(~data[4]&~data[5])))) & (~data[8] ^ ~data[9]) ) |
( (~data[4] & ~data[5] & ~data[6] & ~data[7]) &
(~(~data[8]|~data[9])) ),
threeof6 = ( (((~data[4]^~data[5]) & (~(~data[6]^~data[7]) &
(~data[6]&~data[7]))) | ((~data[6]^~data[7]) &
(~(~data[4]^~data[5]) & (~data[4]&~data[5])))) &
(data[8] & data[9]) ) | ( (((data[4]^data[5]) &
((data[4]&data[5]) ^ (data[6]&data[7]))) &
(data[8] ^ data[9]) ) | ( (((data[4]^data[5]) &
(~(data[6]^data[7]) & (data[6]&data[7])))
| ((data[6]^data[7]) & (~(data[4]^data[5]) &
(data[6]&data[7])))) & ( ~(data[8] | data[9])) ),
newRD = ((noneof6 | oneof6 | twoof6) |
(threeof6 & (data[9:4]==6'b111000))) ? 1'b0 :
((fourof6 | fiveof6 | sixof6) | (threeof6 &
(data[9:4]==6'b000111))) ? 1'b1 : RDreg,
RD = ((noneof4 | oneof4) | (twoof4 &
(data[3:0]==4'b1100))) ? 1'b0 : ((threeof4 | fourof4)
| (twoof4 & (data[3:0]==4'b0011))) ? 1'b1 : newRD;
projects / OpenSPARC-T2-DV / blob