git.zerfleddert.de Git - raggedstone/blob - ethernet/source/pci/pci_rst_int.v

   1 //////////////////////////////////////////////////////////////////////
   2 ////                                                              ////
   3 ////  File name: pci_rst_int.v                                    ////
   4 ////                                                              ////
   5 ////  This file is part of the "PCI bridge" project               ////
   6 ////  http://www.opencores.org/cores/pci/                         ////
   7 ////                                                              ////
   8 ////  Author(s):                                                  ////
   9 ////      - Tadej Markovic, tadej@opencores.org                   ////
  10 ////                                                              ////
  11 ////  All additional information is avaliable in the README.txt   ////
  12 ////  file.                                                       ////
  13 ////                                                              ////
  14 ////                                                              ////
  15 //////////////////////////////////////////////////////////////////////
  16 ////                                                              ////
  17 //// Copyright (C) 2000 Tadej Markovic, tadej@opencores.org       ////
  18 ////                                                              ////
  19 //// This source file may be used and distributed without         ////
  20 //// restriction provided that this copyright statement is not    ////
  21 //// removed from the file and that any derivative work contains  ////
  22 //// the original copyright notice and the associated disclaimer. ////
  23 ////                                                              ////
  24 //// This source file is free software; you can redistribute it   ////
  25 //// and/or modify it under the terms of the GNU Lesser General   ////
  26 //// Public License as published by the Free Software Foundation; ////
  27 //// either version 2.1 of the License, or (at your option) any   ////
  28 //// later version.                                               ////
  29 ////                                                              ////
  30 //// This source is distributed in the hope that it will be       ////
  31 //// useful, but WITHOUT ANY WARRANTY; without even the implied   ////
  32 //// warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR      ////
  33 //// PURPOSE.  See the GNU Lesser General Public License for more ////
  34 //// details.                                                     ////
  35 ////                                                              ////
  36 //// You should have received a copy of the GNU Lesser General    ////
  37 //// Public License along with this source; if not, download it   ////
  38 //// from http://www.opencores.org/lgpl.shtml                     ////
  39 ////                                                              ////
  40 //////////////////////////////////////////////////////////////////////
  41 //
  42 // CVS Revision History
  43 //
  44 // $Log: pci_rst_int.v,v $
  45 // Revision 1.1  2007-03-20 17:50:56  sithglan
  46 // add shit
  47 //
  48 // Revision 1.3  2003/12/19 11:11:30  mihad
  49 // Compact PCI Hot Swap support added.
  50 // New testcases added.
  51 // Specification updated.
  52 // Test application changed to support WB B3 cycles.
  53 //
  54 // Revision 1.2  2003/01/27 16:49:31  mihad
  55 // Changed module and file names. Updated scripts accordingly. FIFO synchronizations changed.
  56 //
  57 // Revision 1.1  2002/02/01 14:43:31  mihad
  58 // *** empty log message ***
  59 //
  60 //
  61 //
  62
  63 `include "pci_constants.v"
  64
  65 // synopsys translate_off
  66 `include "timescale.v"
  67 // synopsys translate_on
  68
  69 // Module is used to switch appropriate reset and interrupt signals with few logic
  70 module pci_rst_int
  71 (
  72         clk_in,
  73         // reset signals
  74         rst_i,
  75         pci_rstn_in,
  76         conf_soft_res_in,
  77         reset,
  78         pci_rstn_out,
  79         pci_rstn_en_out,
  80         rst_o,
  81         // interrupt signals
  82         pci_intan_in,
  83         conf_int_in,
  84         int_i,
  85         pci_intan_out,
  86         pci_intan_en_out,
  87         int_o,
  88         conf_isr_int_prop_out,
  89     init_complete_in
  90 );
  91
  92 input   clk_in;
  93 // RESET inputs and outputs
  94 input   rst_i;
  95 input   pci_rstn_in;
  96 input   conf_soft_res_in;
  97 output  reset;
  98 output  pci_rstn_out;
  99 output  pci_rstn_en_out;
 100 output  rst_o;
 101
 102 // INTERRUPT inputs and outputs
 103 input   pci_intan_in;
 104 input   conf_int_in;
 105 input   int_i;
 106 output  pci_intan_out;
 107 output  pci_intan_en_out;
 108 output  int_o;
 109 output  conf_isr_int_prop_out;
 110
 111 input   init_complete_in ;
 112
 113 /*--------------------------------------------------------------------------------------------------------
 114 RESET logic
 115 --------------------------------------------------------------------------------------------------------*/
 116 assign pci_rstn_out                     = 1'b0 ;
 117 // host implementation of the bridge gets its reset from WISHBONE bus - RST_I and propagates it to PCI bus
 118 `ifdef HOST
 119   assign reset                          = rst_i ;
 120   `ifdef ACTIVE_LOW_OE
 121   assign pci_rstn_en_out        = ~(rst_i || conf_soft_res_in) ;
 122   `else
 123   assign pci_rstn_en_out        = rst_i || conf_soft_res_in ;
 124   `endif
 125   assign rst_o                          = 1'b0 ;
 126 `else
 127 // guest implementation of the bridge gets its reset from PCI bus - RST# and propagates it to WISHBONE bus
 128 `ifdef GUEST
 129   assign reset                          = ~pci_rstn_in ;
 130   assign rst_o                          = (~pci_rstn_in) || conf_soft_res_in ;
 131   `ifdef ACTIVE_LOW_OE
 132   assign pci_rstn_en_out                = 1'b1 ; // disabled
 133   `else
 134   assign pci_rstn_en_out                = 1'b0 ; // disabled
 135   `endif
 136 `endif
 137 `endif
 138
 139 /*--------------------------------------------------------------------------------------------------------
 140 INTERRUPT logic
 141 --------------------------------------------------------------------------------------------------------*/
 142 assign pci_intan_out = 1'b0 ;
 143 // host implementation of the bridge gets its interrupt from PCI bus - INTA# and propagates it to WISHBONE bus
 144 `ifdef HOST
 145   assign conf_isr_int_prop_out  = ~pci_intan_in ;
 146   assign int_o                  = conf_int_in ;
 147   `ifdef ACTIVE_LOW_OE
 148   assign pci_intan_en_out       = 1'b1 ; // disabled
 149   `else
 150   assign pci_intan_en_out       = 1'b0 ; // disabled
 151   `endif
 152 `else
 153 // guest implementation of the bridge gets its interrupt from WISHBONE bus - INT_I and propagates it to PCI bus
 154 `ifdef GUEST
 155     wire interrupt_a_en;
 156     pci_out_reg inta
 157     (
 158         .reset_in     ( reset ),
 159         .clk_in       ( clk_in) ,
 160         .dat_en_in    ( 1'b1 ),
 161         .en_en_in     ( init_complete_in ),
 162         .dat_in       ( 1'b0 ) , // active low
 163         .en_in        ( conf_int_in ) ,
 164         .en_out       ( interrupt_a_en ),
 165         .dat_out      ( )
 166     );
 167   assign conf_isr_int_prop_out = int_i ;
 168   assign int_o                 = 1'b0 ;
 169   assign pci_intan_en_out      = interrupt_a_en ;
 170 `endif
 171 `endif
 172
 173
 174 endmodule