timer_sp804.hh revision 10905 
1/*
2 * Copyright (c) 2010 ARM Limited
3 * All rights reserved
4 *
5 * The license below extends only to copyright in the software and shall
6 * not be construed as granting a license to any other intellectual
7 * property including but not limited to intellectual property relating
8 * to a hardware implementation of the functionality of the software
9 * licensed hereunder.  You may use the software subject to the license
10 * terms below provided that you ensure that this notice is replicated
11 * unmodified and in its entirety in all distributions of the software,
12 * modified or unmodified, in source code or in binary form.
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions are
16 * met: redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer;
18 * redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution;
21 * neither the name of the copyright holders nor the names of its
22 * contributors may be used to endorse or promote products derived from
23 * this software without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
26 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
28 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
29 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
31 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
35 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 *
37 * Authors: Ali Saidi
38 */
39
40#ifndef __DEV_ARM_SP804_HH__
41#define __DEV_ARM_SP804_HH__
42
43#include "dev/arm/amba_device.hh"
44#include "params/Sp804.hh"
45
46/** @file
47 * This implements the dual Sp804 timer block
48 */
49
50class BaseGic;
51
52class Sp804 : public AmbaPioDevice
53{
54  protected:
55    class Timer : public Serializable
56    {
57
58      public:
59        enum {
60            LoadReg    = 0x00,
61            CurrentReg = 0x04,
62            ControlReg = 0x08,
63            IntClear   = 0x0C,
64            RawISR     = 0x10,
65            MaskedISR  = 0x14,
66            BGLoad     = 0x18,
67            Size       = 0x20
68        };
69
70        BitUnion32(CTRL)
71            Bitfield<0>   oneShot;
72            Bitfield<1>   timerSize;
73            Bitfield<3,2> timerPrescale;
74            Bitfield<5>   intEnable;
75            Bitfield<6>   timerMode;
76            Bitfield<7>   timerEnable;
77        EndBitUnion(CTRL)
78
79      protected:
80        std::string _name;
81
82        /** Pointer to parent class */
83        Sp804 *parent;
84
85        /** Number of interrupt to cause/clear */
86        const uint32_t intNum;
87
88        /** Number of ticks in a clock input */
89        const Tick clock;
90
91        /** Control register as specified above */
92        CTRL control;
93
94        /** If timer has caused an interrupt. This is irrespective of
95         * interrupt enable */
96        bool rawInt;
97
98        /** If an interrupt is currently pending. Logical and of CTRL.intEnable
99         * and rawInt */
100        bool pendingInt;
101
102        /** Value to load into counter when periodic mode reaches 0 */
103        uint32_t loadValue;
104
105        /** Called when the counter reaches 0 */
106        void counterAtZero();
107        EventWrapper<Timer, &Timer::counterAtZero> zeroEvent;
108
109      public:
110        /** Restart the counter ticking at val
111         * @param val the value to start at (pre-16 bit masking if en) */
112        void restartCounter(uint32_t val);
113
114        Timer(std::string __name, Sp804 *parent, int int_num, Tick clock);
115
116        std::string name() const { return _name; }
117
118        /** Handle read for a single timer */
119        void read(PacketPtr pkt, Addr daddr);
120
121        /** Handle write for a single timer */
122        void write(PacketPtr pkt, Addr daddr);
123
124        void serialize(CheckpointOut &cp) const M5_ATTR_OVERRIDE;
125        void unserialize(CheckpointIn &cp) M5_ATTR_OVERRIDE;
126    };
127
128    /** Pointer to the GIC for causing an interrupt */
129    BaseGic *gic;
130
131    /** Timers that do the actual work */
132    Timer timer0;
133    Timer timer1;
134
135  public:
136    typedef Sp804Params Params;
137    const Params *
138    params() const
139    {
140        return dynamic_cast<const Params *>(_params);
141    }
142    /**
143      * The constructor for RealView just registers itself with the MMU.
144      * @param p params structure
145      */
146    Sp804(Params *p);
147
148    /**
149     * Handle a read to the device
150     * @param pkt The memory request.
151     * @param data Where to put the data.
152     */
153    virtual Tick read(PacketPtr pkt);
154
155    /**
156     * All writes are simply ignored.
157     * @param pkt The memory request.
158     * @param data the data
159     */
160    virtual Tick write(PacketPtr pkt);
161
162
163    void serialize(CheckpointOut &cp) const M5_ATTR_OVERRIDE;
164    void unserialize(CheckpointIn &cp) M5_ATTR_OVERRIDE;
165};
166
167
168#endif // __DEV_ARM_SP804_HH__
169
170