sc_clock.cc revision 13135:4bb2f323fb1a 
1/*
2 * Copyright 2018 Google, Inc.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met: redistributions of source code must retain the above copyright
7 * notice, this list of conditions and the following disclaimer;
8 * redistributions in binary form must reproduce the above copyright
9 * notice, this list of conditions and the following disclaimer in the
10 * documentation and/or other materials provided with the distribution;
11 * neither the name of the copyright holders nor the names of its
12 * contributors may be used to endorse or promote products derived from
13 * this software without specific prior written permission.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
18 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
19 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
21 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
25 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 *
27 * Authors: Gabe Black
28 */
29
30#include "base/logging.hh"
31#include "base/types.hh"
32#include "sim/core.hh"
33#include "sim/eventq.hh"
34#include "systemc/core/kernel.hh"
35#include "systemc/core/process_types.hh"
36#include "systemc/core/sched_event.hh"
37#include "systemc/core/scheduler.hh"
38#include "systemc/ext/channel/sc_clock.hh"
39#include "systemc/ext/core/sc_module.hh" // for sc_gen_unique_name
40
41namespace sc_gem5
42{
43
44class ClockTick : public ScEvent
45{
46  private:
47    ::sc_core::sc_clock *clock;
48    ::sc_core::sc_time _period;
49    std::string _name;
50    Process *p;
51    ProcessMemberFuncWrapper<::sc_core::sc_clock> funcWrapper;
52    std::string _procName;
53
54  public:
55    ClockTick(::sc_core::sc_clock *clock, bool to,
56            ::sc_core::sc_time _period) :
57        ScEvent([this]() { tick(); }),
58        clock(clock), _period(_period), _name(clock->name()),
59        funcWrapper(clock, to ? &::sc_core::sc_clock::tickUp :
60                                &::sc_core::sc_clock::tickDown)
61    {
62        _name += (to ? ".up_tick" : ".down_tick");
63        _procName = _name + ".p";
64        p = new Method(_procName.c_str(), &funcWrapper);
65        scheduler.reg(p);
66        scheduler.dontInitialize(p);
67    }
68
69    ~ClockTick()
70    {
71        if (scheduled())
72            scheduler.deschedule(this);
73        p->popListNode();
74    }
75
76    void
77    tick()
78    {
79        scheduler.schedule(this, _period);
80        p->ready();
81    }
82};
83
84};
85
86namespace sc_core
87{
88
89sc_clock::sc_clock() :
90    sc_clock(sc_gen_unique_name("clock"), sc_time(1.0, SC_NS),
91            0.5, SC_ZERO_TIME, true)
92{}
93
94sc_clock::sc_clock(const char *name) :
95    sc_clock(name, sc_time(1.0, SC_NS), 0.5, SC_ZERO_TIME, true)
96{}
97
98sc_clock::sc_clock(const char *name, const sc_time &period,
99                   double duty_cycle, const sc_time &start_time,
100                   bool posedge_first) :
101    sc_interface(), sc_signal<bool>(name, posedge_first ? false : true),
102    _period(period), _dutyCycle(duty_cycle), _startTime(start_time),
103    _posedgeFirst(posedge_first)
104{
105    _gem5UpEdge = new ::sc_gem5::ClockTick(this, true, period);
106    _gem5DownEdge = new ::sc_gem5::ClockTick(this, false, period);
107}
108
109sc_clock::sc_clock(const char *name, double period_v, sc_time_unit period_tu,
110                   double duty_cycle) :
111    sc_clock(name, sc_time(period_v, period_tu), duty_cycle, SC_ZERO_TIME,
112            true)
113{}
114
115sc_clock::sc_clock(const char *name, double period_v, sc_time_unit period_tu,
116                   double duty_cycle, double start_time_v,
117                   sc_time_unit start_time_tu, bool posedge_first) :
118    sc_clock(name, sc_time(period_v, period_tu), duty_cycle,
119            sc_time(start_time_v, start_time_tu), posedge_first)
120{}
121
122sc_clock::sc_clock(const char *name, double period, double duty_cycle,
123                   double start_time, bool posedge_first) :
124    sc_clock(name, sc_time(period, true), duty_cycle,
125            sc_time(start_time, true), posedge_first)
126{}
127
128sc_clock::~sc_clock()
129{
130    if (_gem5UpEdge->scheduled())
131        ::sc_gem5::scheduler.deschedule(_gem5UpEdge);
132    if (_gem5DownEdge->scheduled())
133        ::sc_gem5::scheduler.deschedule(_gem5DownEdge);
134    delete _gem5UpEdge;
135    delete _gem5DownEdge;
136}
137
138void
139sc_clock::write(const bool &)
140{
141    panic("write() called on sc_clock.");
142}
143
144const sc_time &sc_clock::period() const { return _period; }
145double sc_clock::duty_cycle() const { return _dutyCycle; }
146const sc_time &sc_clock::start_time() const { return _startTime; }
147bool sc_clock::posedge_first() const { return _posedgeFirst; }
148
149const sc_time &
150sc_clock::time_stamp()
151{
152    warn("%s not implemented.\n", __PRETTY_FUNCTION__);
153    return *(const sc_time *)nullptr;
154}
155
156void
157sc_clock::before_end_of_elaboration()
158{
159    if (_posedgeFirst) {
160        ::sc_gem5::scheduler.schedule(_gem5UpEdge, _startTime);
161        ::sc_gem5::scheduler.schedule(_gem5DownEdge,
162                _startTime + _period * _dutyCycle);
163    } else {
164        ::sc_gem5::scheduler.schedule(_gem5DownEdge, _startTime);
165        ::sc_gem5::scheduler.schedule(_gem5UpEdge,
166                _startTime + _period * (1.0 - _dutyCycle));
167    }
168}
169
170} // namespace sc_core
171