| 1 | // ========== Copyright Header Begin ========================================== |
| 2 | // |
| 3 | // OpenSPARC T2 Processor File: niu_pio_ucb_out32.v |
| 4 | // Copyright (C) 1995-2007 Sun Microsystems, Inc. All Rights Reserved |
| 5 | // 4150 Network Circle, Santa Clara, California 95054, U.S.A. |
| 6 | // |
| 7 | // * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| 8 | // |
| 9 | // This program is free software; you can redistribute it and/or modify |
| 10 | // it under the terms of the GNU General Public License as published by |
| 11 | // the Free Software Foundation; version 2 of the License. |
| 12 | // |
| 13 | // This program is distributed in the hope that it will be useful, |
| 14 | // but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | // GNU General Public License for more details. |
| 17 | // |
| 18 | // You should have received a copy of the GNU General Public License |
| 19 | // along with this program; if not, write to the Free Software |
| 20 | // Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| 21 | // |
| 22 | // For the avoidance of doubt, and except that if any non-GPL license |
| 23 | // choice is available it will apply instead, Sun elects to use only |
| 24 | // the General Public License version 2 (GPLv2) at this time for any |
| 25 | // software where a choice of GPL license versions is made |
| 26 | // available with the language indicating that GPLv2 or any later version |
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| 31 | // CA 95054 USA or visit www.sun.com if you need additional information or |
| 32 | // have any questions. |
| 33 | // |
| 34 | // ========== Copyright Header End ============================================ |
| 35 | //////////////////////////////////////////////////////////////////////////////// |
| 36 | // |
| 37 | // |
| 38 | // Copyright (C) 2003 by Sun Microsystems, Inc. |
| 39 | // |
| 40 | // All rights reserved. No part of this design may be reproduced, |
| 41 | // stored in a retrieval system, or transmitted, in any form or by |
| 42 | // any means, electronic, mechanical, photocopying, recording, or |
| 43 | // otherwise, without prior written permission of Sun Microsystems, |
| 44 | // Inc. |
| 45 | // |
| 46 | // Sun Proprietary/Confidential |
| 47 | // |
| 48 | // |
| 49 | // Primary Contact: Jimmy.Lau@sun.com x48745 |
| 50 | // Description: This interface is modified based on Niagra ucb_bus_in. |
| 51 | // Instaniated by UCB modules and NCU to receive |
| 52 | // packets on the UCB bus. This module supports 32 bit |
| 53 | // data bus in. |
| 54 | // |
| 55 | // Revision: 1. March 08, 2004 - John Lo |
| 56 | // Changed modules name from |
| 57 | // ucb_bus_out32_niu.v to niu_pio_ucb_out32 |
| 58 | // |
| 59 | // Changed enl2clk to clk. |
| 60 | // |
| 61 | // |
| 62 | //////////////////////////////////////////////////////////////////////////////// |
| 63 | |
| 64 | |
| 65 | module niu_pio_ucb_out32 ( |
| 66 | // Global // |
| 67 | clk, |
| 68 | reset, |
| 69 | // UCB bus // |
| 70 | vld, |
| 71 | data, |
| 72 | stall, |
| 73 | // Local unit // |
| 74 | outdata_buf_busy, |
| 75 | outdata_buf_wr, |
| 76 | outdata_buf_in, |
| 77 | outdata_vec_in ); |
| 78 | |
| 79 | |
| 80 | // Globals |
| 81 | input clk; |
| 82 | input reset; |
| 83 | |
| 84 | // UCB bus interface |
| 85 | output vld; |
| 86 | output [31:0] data; |
| 87 | input stall; |
| 88 | |
| 89 | // Local interface |
| 90 | output outdata_buf_busy; |
| 91 | input outdata_buf_wr; |
| 92 | input [127:0] outdata_buf_in; |
| 93 | input [3:0] outdata_vec_in; |
| 94 | |
| 95 | |
| 96 | |
| 97 | // Local signals |
| 98 | wire stall_d1; |
| 99 | wire [3:0] outdata_vec; |
| 100 | wire [3:0] outdata_vec_next; |
| 101 | wire [127:0] outdata_buf; |
| 102 | wire [127:0] outdata_buf_next; |
| 103 | wire load_outdata; |
| 104 | wire shift_outdata; |
| 105 | |
| 106 | |
| 107 | //////////////////////////////////////////////////////////////////////// |
| 108 | // Code starts here |
| 109 | //////////////////////////////////////////////////////////////////////// |
| 110 | /************************************************************ |
| 111 | * UCB bus interface flops |
| 112 | ************************************************************/ |
| 113 | assign vld = outdata_vec[0]; |
| 114 | assign data[31:0] = outdata_buf[31:0]; |
| 115 | |
| 116 | dffr #(1) stall_d1_ff (.d(stall), |
| 117 | .clk(clk), |
| 118 | .reset(reset), |
| 119 | .q(stall_d1) ); |
| 120 | |
| 121 | |
| 122 | /************************************************************ |
| 123 | * Outbound Data |
| 124 | ************************************************************/ |
| 125 | // accept new data only if there is none being processed |
| 126 | assign load_outdata = outdata_buf_wr & ~outdata_buf_busy; |
| 127 | |
| 128 | assign outdata_buf_busy = outdata_vec[0] | stall_d1; |
| 129 | |
| 130 | assign shift_outdata = outdata_vec[0] & ~stall_d1; |
| 131 | |
| 132 | assign outdata_vec_next[3:0] = load_outdata ? outdata_vec_in[3:0]: |
| 133 | shift_outdata ? (outdata_vec[3:0] >> 1) : |
| 134 | outdata_vec[3:0]; |
| 135 | |
| 136 | dffr #(4) outdata_vec_ff (.d(outdata_vec_next[3:0]), |
| 137 | .clk(clk), |
| 138 | .reset(reset), |
| 139 | .q(outdata_vec[3:0]) ); |
| 140 | |
| 141 | assign outdata_buf_next[127:0] = load_outdata ? outdata_buf_in[127:0]: |
| 142 | shift_outdata ? (outdata_buf[127:0] >> 32): |
| 143 | outdata_buf[127:0]; |
| 144 | df1 #(96) outdata_buf_msw_ff (.d(outdata_buf_next[127:32]), |
| 145 | .clk(clk), |
| 146 | .q(outdata_buf[127:32]) ); |
| 147 | |
| 148 | dffr #(32) outdata_buf_lsw_ff (.d(outdata_buf_next[31:0]), |
| 149 | .clk(clk), |
| 150 | .reset(reset), |
| 151 | .q(outdata_buf[31:0]) ); |
| 152 | |
| 153 | |
| 154 | endmodule // niu_pio_ucb_out32 |
| 155 | |
| 156 | |
| 157 | |
| 158 | |
| 159 | |
| 160 | |
| 161 | |