1/*
2 * Copyright (c) 2015 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 * Copyright (c) 2001-2005 The Regents of The University of Michigan
15 * Copyright (c) 2010 Advanced Micro Devices, Inc.
16 * All rights reserved.
17 *
18 * Redistribution and use in source and binary forms, with or without
19 * modification, are permitted provided that the following conditions are
20 * met: redistributions of source code must retain the above copyright
21 * notice, this list of conditions and the following disclaimer;
22 * redistributions in binary form must reproduce the above copyright
23 * notice, this list of conditions and the following disclaimer in the
24 * documentation and/or other materials provided with the distribution;
25 * neither the name of the copyright holders nor the names of its
26 * contributors may be used to endorse or promote products derived from
27 * this software without specific prior written permission.
28 *
29 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
30 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
31 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
32 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
33 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
34 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
35 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
36 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
37 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
38 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
39 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
40 *
41 * Authors: Steve Reinhardt
42 * Nathan Binkert
43 */
44
45/* @file
46 * User Console Definitions
47 */
48
49#ifndef __SIM_OBJECT_HH__
50#define __SIM_OBJECT_HH__
51
52#include <string>
53#include <vector>
54
55#include "params/SimObject.hh"
56#include "sim/drain.hh"
57#include "sim/eventq.hh"
58#include "sim/eventq_impl.hh"
59#include "sim/serialize.hh"
60
61class EventManager;
62class ProbeManager;
63
64/**
65 * Abstract superclass for simulation objects. Represents things that
66 * correspond to physical components and can be specified via the
67 * config file (CPUs, caches, etc.).
68 *
69 * SimObject initialization is controlled by the instantiate method in
70 * src/python/m5/simulate.py. There are slightly different
71 * initialization paths when starting the simulation afresh and when
72 * loading from a checkpoint. After instantiation and connecting
73 * ports, simulate.py initializes the object using the following call
74 * sequence:
75 *
76 * <ol>
77 * <li>SimObject::init()
78 * <li>SimObject::regStats()
79 * <li><ul>
80 * <li>SimObject::initState() if starting afresh.
81 * <li>SimObject::loadState() if restoring from a checkpoint.
82 * </ul>
83 * <li>SimObject::resetStats()
84 * <li>SimObject::startup()
85 * <li>Drainable::drainResume() if resuming from a checkpoint.
86 * </ol>
87 *
88 * @note Whenever a method is called on all objects in the simulator's
89 * object tree (e.g., init(), startup(), or loadState()), a pre-order
90 * depth-first traversal is performed (see descendants() in
91 * SimObject.py). This has the effect of calling the method on the
92 * parent node <i>before</i> its children.
93 */
94class SimObject : public EventManager, public Serializable, public Drainable
95{
96 private:
97 typedef std::vector<SimObject *> SimObjectList;
98
99 /** List of all instantiated simulation objects. */
100 static SimObjectList simObjectList;
101
102 /** Manager coordinates hooking up probe points with listeners. */
103 ProbeManager *probeManager;
104
105 protected:
106 /** Cached copy of the object parameters. */
107 const SimObjectParams *_params;
108
109 public:
110 typedef SimObjectParams Params;
111 const Params *params() const { return _params; }
112 SimObject(const Params *_params);
113 virtual ~SimObject();
114
115 public:
116
117 virtual const std::string name() const { return params()->name; }
118
119 /**
120 * init() is called after all C++ SimObjects have been created and
121 * all ports are connected. Initializations that are independent
122 * of unserialization but rely on a fully instantiated and
123 * connected SimObject graph should be done here.
124 */
125 virtual void init();
126
127 /**
128 * loadState() is called on each SimObject when restoring from a
129 * checkpoint. The default implementation simply calls
130 * unserialize() if there is a corresponding section in the
131 * checkpoint. However, objects can override loadState() to get
132 * other behaviors, e.g., doing other programmed initializations
133 * after unserialize(), or complaining if no checkpoint section is
134 * found.
135 *
136 * @param cp Checkpoint to restore the state from.
137 */
138 virtual void loadState(CheckpointIn &cp);
139
140 /**
141 * initState() is called on each SimObject when *not* restoring
142 * from a checkpoint. This provides a hook for state
143 * initializations that are only required for a "cold start".
144 */
145 virtual void initState();
146
147 /**
148 * Register statistics for this object.
149 */
150 virtual void regStats();
151
152 /**
153 * Reset statistics associated with this object.
154 */
155 virtual void resetStats();
156
157 /**
158 * Register probe points for this object.
159 */
160 virtual void regProbePoints();
161
162 /**
163 * Register probe listeners for this object.
164 */
165 virtual void regProbeListeners();
166
167 /**
168 * Get the probe manager for this object.
169 */
170 ProbeManager *getProbeManager();
171
172 /**
173 * startup() is the final initialization call before simulation.
174 * All state is initialized (including unserialized state, if any,
175 * such as the curTick() value), so this is the appropriate place to
176 * schedule initial event(s) for objects that need them.
177 */
178 virtual void startup();
179
180 /**
181 * Provide a default implementation of the drain interface for
182 * objects that don't need draining.
183 */
184 DrainState drain() override { return DrainState::Drained; }
185
186 /**
187 * Write back dirty buffers to memory using functional writes.
188 *
189 * After returning, an object implementing this method should have
190 * written all its dirty data back to memory. This method is
191 * typically used to prepare a system with caches for
192 * checkpointing.
193 */
194 virtual void memWriteback() {};
195
196 /**
197 * Invalidate the contents of memory buffers.
198 *
199 * When the switching to hardware virtualized CPU models, we need
200 * to make sure that we don't have any cached state in the system
201 * that might become stale when we return. This method is used to
202 * flush all such state back to main memory.
203 *
204 * @warn This does <i>not</i> cause any dirty state to be written
205 * back to memory.
206 */
207 virtual void memInvalidate() {};
208
209 void serialize(CheckpointOut &cp) const override {};
210 void unserialize(CheckpointIn &cp) override {};
211
212 /**
213 * Serialize all SimObjects in the system.
214 */
215 static void serializeAll(CheckpointOut &cp);
216
217#ifdef DEBUG
218 public:
219 bool doDebugBreak;
220 static void debugObjectBreak(const std::string &objs);
221#endif
222
223 /**
224 * Find the SimObject with the given name and return a pointer to
225 * it. Primarily used for interactive debugging. Argument is
226 * char* rather than std::string to make it callable from gdb.
227 */
228 static SimObject *find(const char *name);
229};
230
231/**
232 * Base class to wrap object resolving functionality.
233 *
234 * This can be provided to the serialization framework to allow it to
235 * map object names onto C++ objects.
236 */
237class SimObjectResolver
238{
239 public:
240 virtual ~SimObjectResolver() { }
241
242 // Find a SimObject given a full path name
243 virtual SimObject *resolveSimObject(const std::string &name) = 0;
244};
245
246#ifdef DEBUG
247void debugObjectBreak(const char *objs);
248#endif
249
250#endif // __SIM_OBJECT_HH__