1/*
2 * Copyright (c) 1999-2008 Mark D. Hill and David A. Wood
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
29#include "mem/ruby/structures/TimerTable.hh"
30
31#include "mem/ruby/system/RubySystem.hh"
32
33TimerTable::TimerTable()
34 : m_next_time(0)
35{
36 m_consumer_ptr = NULL;
37 m_clockobj_ptr = NULL;
38
39 m_next_valid = false;
40 m_next_address = 0;
41}
42
43bool
44TimerTable::isReady() const
45{
46 if (m_map.empty())
47 return false;
48
49 if (!m_next_valid) {
50 updateNext();
51 }
52 assert(m_next_valid);
53 return (m_clockobj_ptr->curCycle() >= m_next_time);
54}
55
56Addr
57TimerTable::readyAddress() const
58{
59 assert(isReady());
60
61 if (!m_next_valid) {
62 updateNext();
63 }
64 assert(m_next_valid);
65 return m_next_address;
66}
67
68void
69TimerTable::set(Addr address, Cycles relative_latency)
70{
71 assert(address == makeLineAddress(address));
72 assert(relative_latency > 0);
73 assert(!m_map.count(address));
74
75 Cycles ready_time = m_clockobj_ptr->curCycle() + relative_latency;
76 m_map[address] = ready_time;
77 assert(m_consumer_ptr != NULL);
78 m_consumer_ptr->
79 scheduleEventAbsolute(m_clockobj_ptr->clockPeriod() * ready_time);
80 m_next_valid = false;
81
82 // Don't always recalculate the next ready address
83 if (ready_time <= m_next_time) {
84 m_next_valid = false;
85 }
86}
87
88void
89TimerTable::unset(Addr address)
90{
91 assert(address == makeLineAddress(address));
92 assert(m_map.count(address));
93 m_map.erase(address);
94
95 // Don't always recalculate the next ready address
96 if (address == m_next_address) {
97 m_next_valid = false;
98 }
99}
100
101void
102TimerTable::print(std::ostream& out) const
103{
104}
105
106void
107TimerTable::updateNext() const
108{
109 if (m_map.empty()) {
110 assert(!m_next_valid);
111 return;
112 }
113
114 AddressMap::const_iterator i = m_map.begin();
115 AddressMap::const_iterator end = m_map.end();
116
117 m_next_address = i->first;
118 m_next_time = i->second;
119 ++i;
120
121 for (; i != end; ++i) {
122 if (i->second < m_next_time) {
123 m_next_address = i->first;
124 m_next_time = i->second;
125 }
126 }
127
128 m_next_valid = true;
129}