1/*
2 * Copyright (c) 2012 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: Andreas Hansson
38 */
39
40/**
41 * @file
42 * ClockedObject declaration and implementation.
43 */
44
45#ifndef __SIM_CLOCKED_OBJECT_HH__
46#define __SIM_CLOCKED_OBJECT_HH__
47
48#include "base/intmath.hh"
49#include "params/ClockedObject.hh"
| 1/*
2 * Copyright (c) 2012 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: Andreas Hansson
38 */
39
40/**
41 * @file
42 * ClockedObject declaration and implementation.
43 */
44
45#ifndef __SIM_CLOCKED_OBJECT_HH__
46#define __SIM_CLOCKED_OBJECT_HH__
47
48#include "base/intmath.hh"
49#include "params/ClockedObject.hh"
|
50#include "sim/sim_object.hh"
51
52/**
53 * The ClockedObject class extends the SimObject with a clock and
54 * accessor functions to relate ticks to the cycles of the object.
55 */
56class ClockedObject : public SimObject
57{
58
59 private:
60
61 // the tick value of the next clock edge (>= curTick()) at the
62 // time of the last call to update()
63 mutable Tick tick;
64
65 // The cycle counter value corresponding to the current value of
66 // 'tick'
67 mutable Cycles cycle;
68
69 /**
70 * Prevent inadvertent use of the copy constructor and assignment
71 * operator by making them private.
72 */
73 ClockedObject(ClockedObject&);
74 ClockedObject& operator=(ClockedObject&);
75
76 /**
77 * Align cycle and tick to the next clock edge if not already done.
78 */
79 void update() const
80 {
81 // both tick and cycle are up-to-date and we are done, note
82 // that the >= is important as it captures cases where tick
83 // has already passed curTick()
84 if (tick >= curTick())
85 return;
86
87 // optimise for the common case and see if the tick should be
88 // advanced by a single clock period
89 tick += clock;
90 ++cycle;
91
92 // see if we are done at this point
93 if (tick >= curTick())
94 return;
95
96 // if not, we have to recalculate the cycle and tick, we
97 // perform the calculations in terms of relative cycles to
98 // allow changes to the clock period in the future
99 Cycles elapsedCycles(divCeil(curTick() - tick, clock));
100 cycle += elapsedCycles;
101 tick += elapsedCycles * clock;
102 }
103
104 protected:
105
106 // Clock period in ticks
107 Tick clock;
108
109 /**
110 * Create a clocked object and set the clock based on the
111 * parameters.
112 */
113 ClockedObject(const ClockedObjectParams* p) :
114 SimObject(p), tick(0), cycle(0), clock(p->clock)
115 { }
116
117 /**
118 * Virtual destructor due to inheritance.
119 */
120 virtual ~ClockedObject() { }
121
122 /**
123 * Reset the object's clock using the current global tick value. Likely
124 * to be used only when the global clock is reset. Currently, this done
125 * only when Ruby is done warming up the memory system.
126 */
127 void resetClock() const
128 {
129 Cycles elapsedCycles(divCeil(curTick(), clock));
130 cycle = elapsedCycles;
131 tick = elapsedCycles * clock;
132 }
133
134 public:
135
136 /**
137 * Determine the tick when a cycle begins, by default the current
138 * one, but the argument also enables the caller to determine a
139 * future cycle.
140 *
141 * @param cycles The number of cycles into the future
142 *
143 * @return The tick when the clock edge occurs
144 */
145 inline Tick clockEdge(Cycles cycles = Cycles(0)) const
146 {
147 // align tick to the next clock edge
148 update();
149
150 // figure out when this future cycle is
151 return tick + clock * cycles;
152 }
153
154 /**
155 * Determine the current cycle, corresponding to a tick aligned to
156 * a clock edge.
157 *
158 * @return The current cycle count
159 */
160 inline Cycles curCycle() const
161 {
162 // align cycle to the next clock edge.
163 update();
164
165 return cycle;
166 }
167
168 /**
169 * Based on the clock of the object, determine the tick when the
170 * next cycle begins, in other words, return the next clock edge.
171 *
172 * @return The tick when the next cycle starts
173 */
174 Tick nextCycle() const
175 { return clockEdge(); }
176
177 inline uint64_t frequency() const { return SimClock::Frequency / clock; }
178
179 inline Tick clockPeriod() const { return clock; }
180
181 inline Cycles ticksToCycles(Tick tick) const
182 { return Cycles(tick / clock); }
183
184};
185
186#endif //__SIM_CLOCKED_OBJECT_HH__
| 51#include "sim/sim_object.hh"
52
53/**
54 * The ClockedObject class extends the SimObject with a clock and
55 * accessor functions to relate ticks to the cycles of the object.
56 */
57class ClockedObject : public SimObject
58{
59
60 private:
61
62 // the tick value of the next clock edge (>= curTick()) at the
63 // time of the last call to update()
64 mutable Tick tick;
65
66 // The cycle counter value corresponding to the current value of
67 // 'tick'
68 mutable Cycles cycle;
69
70 /**
71 * Prevent inadvertent use of the copy constructor and assignment
72 * operator by making them private.
73 */
74 ClockedObject(ClockedObject&);
75 ClockedObject& operator=(ClockedObject&);
76
77 /**
78 * Align cycle and tick to the next clock edge if not already done.
79 */
80 void update() const
81 {
82 // both tick and cycle are up-to-date and we are done, note
83 // that the >= is important as it captures cases where tick
84 // has already passed curTick()
85 if (tick >= curTick())
86 return;
87
88 // optimise for the common case and see if the tick should be
89 // advanced by a single clock period
90 tick += clock;
91 ++cycle;
92
93 // see if we are done at this point
94 if (tick >= curTick())
95 return;
96
97 // if not, we have to recalculate the cycle and tick, we
98 // perform the calculations in terms of relative cycles to
99 // allow changes to the clock period in the future
100 Cycles elapsedCycles(divCeil(curTick() - tick, clock));
101 cycle += elapsedCycles;
102 tick += elapsedCycles * clock;
103 }
104
105 protected:
106
107 // Clock period in ticks
108 Tick clock;
109
110 /**
111 * Create a clocked object and set the clock based on the
112 * parameters.
113 */
114 ClockedObject(const ClockedObjectParams* p) :
115 SimObject(p), tick(0), cycle(0), clock(p->clock)
116 { }
117
118 /**
119 * Virtual destructor due to inheritance.
120 */
121 virtual ~ClockedObject() { }
122
123 /**
124 * Reset the object's clock using the current global tick value. Likely
125 * to be used only when the global clock is reset. Currently, this done
126 * only when Ruby is done warming up the memory system.
127 */
128 void resetClock() const
129 {
130 Cycles elapsedCycles(divCeil(curTick(), clock));
131 cycle = elapsedCycles;
132 tick = elapsedCycles * clock;
133 }
134
135 public:
136
137 /**
138 * Determine the tick when a cycle begins, by default the current
139 * one, but the argument also enables the caller to determine a
140 * future cycle.
141 *
142 * @param cycles The number of cycles into the future
143 *
144 * @return The tick when the clock edge occurs
145 */
146 inline Tick clockEdge(Cycles cycles = Cycles(0)) const
147 {
148 // align tick to the next clock edge
149 update();
150
151 // figure out when this future cycle is
152 return tick + clock * cycles;
153 }
154
155 /**
156 * Determine the current cycle, corresponding to a tick aligned to
157 * a clock edge.
158 *
159 * @return The current cycle count
160 */
161 inline Cycles curCycle() const
162 {
163 // align cycle to the next clock edge.
164 update();
165
166 return cycle;
167 }
168
169 /**
170 * Based on the clock of the object, determine the tick when the
171 * next cycle begins, in other words, return the next clock edge.
172 *
173 * @return The tick when the next cycle starts
174 */
175 Tick nextCycle() const
176 { return clockEdge(); }
177
178 inline uint64_t frequency() const { return SimClock::Frequency / clock; }
179
180 inline Tick clockPeriod() const { return clock; }
181
182 inline Cycles ticksToCycles(Tick tick) const
183 { return Cycles(tick / clock); }
184
185};
186
187#endif //__SIM_CLOCKED_OBJECT_HH__
|