i8259.hh revision 5632 
1/*
2 * Copyright (c) 2004-2005 The Regents of The University of Michigan
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Authors: Gabe Black
29 */
30
31#ifndef __DEV_X86_I8259_HH__
32#define __DEV_X86_I8259_HH__
33
34#include "dev/io_device.hh"
35#include "params/I8259.hh"
36
37namespace X86ISA
38{
39
40class I8259 : public BasicPioDevice
41{
42  protected:
43    Tick latency;
44    I8259 *master;
45
46    // Interrupt Request Register
47    uint8_t IRR;
48    // In Service Register
49    uint8_t ISR;
50    // Interrupt Mask Register
51    uint8_t IMR;
52
53    bool cascadeMode;
54    // A bit vector of lines with slaves attached, or the slave id, depending
55    // on if this is a master or slave PIC.
56    uint8_t cascadeBits;
57
58    bool edgeTriggered;
59    bool readIRR;
60
61    // State machine information for reading in initialization control words.
62    bool expectICW4;
63    int initControlWord;
64
65  public:
66    typedef I8259Params Params;
67
68    const Params *
69    params() const
70    {
71        return dynamic_cast<const Params *>(_params);
72    }
73
74    I8259(Params * p) : BasicPioDevice(p)
75    {
76        pioSize = 2;
77        initControlWord = 0;
78        readIRR = true;
79        latency = p->pio_latency;
80        master = p->master;
81    }
82
83    Tick read(PacketPtr pkt);
84
85    Tick write(PacketPtr pkt);
86
87    void signalInterrupt(int line);
88};
89
90}; // namespace X86ISA
91
92#endif //__DEV_X86_I8259_HH__
93