summaryrefslogtreecommitdiff
path: root/src/cpu/simple/timing.hh
blob: 65cbe309897514766ca6a1325f0db98cf04938ca (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
/*
 * Copyright (c) 2002-2005 The Regents of The University of Michigan
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met: redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer;
 * redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution;
 * neither the name of the copyright holders nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Authors: Steve Reinhardt
 */

#ifndef __CPU_SIMPLE_TIMING_HH__
#define __CPU_SIMPLE_TIMING_HH__

#include "cpu/simple/base.hh"
#include "cpu/translation.hh"

#include "params/TimingSimpleCPU.hh"

class TimingSimpleCPU : public BaseSimpleCPU
{
  public:

    TimingSimpleCPU(TimingSimpleCPUParams * params);
    virtual ~TimingSimpleCPU();

    virtual void init();

  public:
    Event *drainEvent;

  private:

    /*
     * If an access needs to be broken into fragments, currently at most two,
     * the the following two classes are used as the sender state of the
     * packets so the CPU can keep track of everything. In the main packet
     * sender state, there's an array with a spot for each fragment. If a
     * fragment has already been accepted by the CPU, aka isn't waiting for
     * a retry, it's pointer is NULL. After each fragment has successfully
     * been processed, the "outstanding" counter is decremented. Once the
     * count is zero, the entire larger access is complete.
     */
    class SplitMainSenderState : public Packet::SenderState
    {
      public:
        int outstanding;
        PacketPtr fragments[2];

        int
        getPendingFragment()
        {
            if (fragments[0]) {
                return 0;
            } else if (fragments[1]) {
                return 1;
            } else {
                return -1;
            }
        }
    };

    class SplitFragmentSenderState : public Packet::SenderState
    {
      public:
        SplitFragmentSenderState(PacketPtr _bigPkt, int _index) :
            bigPkt(_bigPkt), index(_index)
        {}
        PacketPtr bigPkt;
        int index;

        void
        clearFromParent()
        {
            SplitMainSenderState * main_send_state =
                dynamic_cast<SplitMainSenderState *>(bigPkt->senderState);
            main_send_state->fragments[index] = NULL;
        }
    };

    class FetchTranslation : public BaseTLB::Translation
    {
      protected:
        TimingSimpleCPU *cpu;

      public:
        FetchTranslation(TimingSimpleCPU *_cpu)
            : cpu(_cpu)
        {}

        void
        finish(Fault fault, RequestPtr req, ThreadContext *tc,
               BaseTLB::Mode mode)
        {
            cpu->sendFetch(fault, req, tc);
        }
    };
    FetchTranslation fetchTranslation;

    void sendData(RequestPtr req, uint8_t *data, uint64_t *res, bool read);
    void sendSplitData(RequestPtr req1, RequestPtr req2, RequestPtr req,
                       uint8_t *data, bool read);

    void translationFault(Fault fault);

    void buildPacket(PacketPtr &pkt, RequestPtr req, bool read);
    void buildSplitPacket(PacketPtr &pkt1, PacketPtr &pkt2,
            RequestPtr req1, RequestPtr req2, RequestPtr req,
            uint8_t *data, bool read);

    bool handleReadPacket(PacketPtr pkt);
    // This function always implicitly uses dcache_pkt.
    bool handleWritePacket();

    class CpuPort : public Port
    {
      protected:
        TimingSimpleCPU *cpu;
        Tick lat;

      public:

        CpuPort(const std::string &_name, TimingSimpleCPU *_cpu, Tick _lat)
            : Port(_name, _cpu), cpu(_cpu), lat(_lat)
        { }

        bool snoopRangeSent;

      protected:

        virtual Tick recvAtomic(PacketPtr pkt);

        virtual void recvFunctional(PacketPtr pkt);

        virtual void recvStatusChange(Status status);

        virtual void getDeviceAddressRanges(AddrRangeList &resp,
                                            bool &snoop)
        { resp.clear(); snoop = false; }

        struct TickEvent : public Event
        {
            PacketPtr pkt;
            TimingSimpleCPU *cpu;

            TickEvent(TimingSimpleCPU *_cpu) : cpu(_cpu) {}
            const char *description() const { return "Timing CPU tick"; }
            void schedule(PacketPtr _pkt, Tick t);
        };

    };

    class IcachePort : public CpuPort
    {
      public:

        IcachePort(TimingSimpleCPU *_cpu, Tick _lat)
            : CpuPort(_cpu->name() + "-iport", _cpu, _lat), tickEvent(_cpu)
        { }

      protected:

        virtual bool recvTiming(PacketPtr pkt);

        virtual void recvRetry();

        struct ITickEvent : public TickEvent
        {

            ITickEvent(TimingSimpleCPU *_cpu)
                : TickEvent(_cpu) {}
            void process();
            const char *description() const { return "Timing CPU icache tick"; }
        };

        ITickEvent tickEvent;

    };

    class DcachePort : public CpuPort
    {
      public:

        DcachePort(TimingSimpleCPU *_cpu, Tick _lat)
            : CpuPort(_cpu->name() + "-dport", _cpu, _lat), tickEvent(_cpu)
        { }

        virtual void setPeer(Port *port);

      protected:

        virtual bool recvTiming(PacketPtr pkt);

        virtual void recvRetry();

        struct DTickEvent : public TickEvent
        {
            DTickEvent(TimingSimpleCPU *_cpu)
                : TickEvent(_cpu) {}
            void process();
            const char *description() const { return "Timing CPU dcache tick"; }
        };

        DTickEvent tickEvent;

    };

    IcachePort icachePort;
    DcachePort dcachePort;

    PacketPtr ifetch_pkt;
    PacketPtr dcache_pkt;

    Tick previousTick;

  public:

    virtual Port *getPort(const std::string &if_name, int idx = -1);

    virtual void serialize(std::ostream &os);
    virtual void unserialize(Checkpoint *cp, const std::string &section);

    virtual unsigned int drain(Event *drain_event);
    virtual void resume();

    void switchOut();
    void takeOverFrom(BaseCPU *oldCPU);

    virtual void activateContext(int thread_num, int delay);
    virtual void suspendContext(int thread_num);

    template <class T>
    Fault read(Addr addr, T &data, unsigned flags);

    Fault readBytes(Addr addr, uint8_t *data, unsigned size, unsigned flags);

    template <class T>
    Fault write(T data, Addr addr, unsigned flags, uint64_t *res);

    Fault writeBytes(uint8_t *data, unsigned size,
                     Addr addr, unsigned flags, uint64_t *res);

    void fetch();
    void sendFetch(Fault fault, RequestPtr req, ThreadContext *tc);
    void completeIfetch(PacketPtr );
    void completeDataAccess(PacketPtr pkt);
    void advanceInst(Fault fault);

    /**
     * Print state of address in memory system via PrintReq (for
     * debugging).
     */
    void printAddr(Addr a);

    /**
     * Finish a DTB translation.
     * @param state The DTB translation state.
     */
    void finishTranslation(WholeTranslationState *state);

  private:

    // The backend for writeBytes and write. It's the same as writeBytes, but
    // doesn't make a copy of data.
    Fault writeTheseBytes(uint8_t *data, unsigned size,
                          Addr addr, unsigned flags, uint64_t *res);

    typedef EventWrapper<TimingSimpleCPU, &TimingSimpleCPU::fetch> FetchEvent;
    FetchEvent fetchEvent;

    struct IprEvent : Event {
        Packet *pkt;
        TimingSimpleCPU *cpu;
        IprEvent(Packet *_pkt, TimingSimpleCPU *_cpu, Tick t);
        virtual void process();
        virtual const char *description() const;
    };

    void completeDrain();
};

#endif // __CPU_SIMPLE_TIMING_HH__