1/*
2 * Copyright (c) 2010 Advanced Micro Devices, Inc.
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions are
7 * met: redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer;
9 * redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution;
12 * neither the name of the copyright holders nor the names of its
13 * contributors may be used to endorse or promote products derived from
14 * this software without specific prior written permission.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 *
28 * Author: Lisa Hsu
29 *
30 */
31
32#ifndef __MEM_RUBY_STRUCTURES_WIREBUFFER_HH__
33#define __MEM_RUBY_STRUCTURES_WIREBUFFER_HH__
34
35#include <iostream>
36#include <string>
37#include <vector>
38
39#include "mem/ruby/common/Consumer.hh"
40#include "mem/ruby/slicc_interface/Message.hh"
41#include "params/RubyWireBuffer.hh"
42#include "sim/sim_object.hh"
43
44//////////////////////////////////////////////////////////////////////////////
45// This object was written to literally mimic a Wire in Ruby, in the sense
46// that there is no way for messages to get reordered en route on the WireBuffer.
47// With Message Buffers, even if randomization is off and ordered is on,
48// messages can arrive in different orders than they were sent because of
49// network issues. This mimics a Wire, such that that is not possible. This can
50// allow for messages between closely coupled controllers that are not actually
51// separated by a network in real systems to simplify coherence.
52/////////////////////////////////////////////////////////////////////////////
53
54class Message;
55
56class WireBuffer : public SimObject
57{
58  public:
59    typedef RubyWireBufferParams Params;
60    WireBuffer(const Params *p);
61    void init();
62
63    ~WireBuffer();
64
65    void wakeup();
66
67    void setConsumer(Consumer* consumer_ptr)
68    {
69        m_consumer_ptr = consumer_ptr;
70    }
71    Consumer* getConsumer() { return m_consumer_ptr; };
72    void setDescription(const std::string& name) { m_description = name; };
73    std::string getDescription() { return m_description; };
74
75    void enqueue(MsgPtr message, Tick current_time, Tick delta);
76    void dequeue(Tick current_time);
77    const Message* peek();
78    void recycle(Tick current_time, Tick recycle_latency);
79    bool isReady(Tick current_time);
80    // infinite queue length
81    bool areNSlotsAvailable(int n, Tick current_time) { return true; };
82
83    void print(std::ostream& out) const;
84    uint64_t m_msg_counter;
85
86  private:
87    // Private copy constructor and assignment operator
88    WireBuffer (const WireBuffer& obj);
89    WireBuffer& operator=(const WireBuffer& obj);
90
91    // data members
92    Consumer* m_consumer_ptr;  // Consumer to signal a wakeup()
93    std::string m_description;
94
95    // queues where memory requests live
96    std::vector<MsgPtr> m_message_queue;
97};
98
99std::ostream& operator<<(std::ostream& out, const WireBuffer& obj);
100
101#endif // __MEM_RUBY_STRUCTURES_WireBuffer_HH__
102