BankedArray.cc (11049:dfb0aa3f0649) BankedArray.cc (11061:25b53a7195f7)
1/*
2 * Copyright (c) 2012 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: Brad Beckmann
29 *
30 */
31
32#include "base/intmath.hh"
33#include "mem/ruby/structures/BankedArray.hh"
34#include "mem/ruby/system/System.hh"
35
36BankedArray::BankedArray(unsigned int banks, Cycles accessLatency,
37 unsigned int startIndexBit, RubySystem *rs)
38 : m_ruby_system(rs)
39{
40 this->banks = banks;
41 this->accessLatency = accessLatency;
42 this->startIndexBit = startIndexBit;
43
44 if (banks != 0) {
45 bankBits = floorLog2(banks);
46 }
47
48 busyBanks.resize(banks);
49}
50
51bool
1/*
2 * Copyright (c) 2012 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: Brad Beckmann
29 *
30 */
31
32#include "base/intmath.hh"
33#include "mem/ruby/structures/BankedArray.hh"
34#include "mem/ruby/system/System.hh"
35
36BankedArray::BankedArray(unsigned int banks, Cycles accessLatency,
37 unsigned int startIndexBit, RubySystem *rs)
38 : m_ruby_system(rs)
39{
40 this->banks = banks;
41 this->accessLatency = accessLatency;
42 this->startIndexBit = startIndexBit;
43
44 if (banks != 0) {
45 bankBits = floorLog2(banks);
46 }
47
48 busyBanks.resize(banks);
49}
50
51bool
52BankedArray::tryAccess(int64 idx)
52BankedArray::tryAccess(int64_t idx)
53{
54 if (accessLatency == 0)
55 return true;
56
57 unsigned int bank = mapIndexToBank(idx);
58 assert(bank < banks);
59
60 if (busyBanks[bank].endAccess >= curTick()) {
61 return false;
62 }
63
64 return true;
65}
66
67void
53{
54 if (accessLatency == 0)
55 return true;
56
57 unsigned int bank = mapIndexToBank(idx);
58 assert(bank < banks);
59
60 if (busyBanks[bank].endAccess >= curTick()) {
61 return false;
62 }
63
64 return true;
65}
66
67void
68BankedArray::reserve(int64 idx)
68BankedArray::reserve(int64_t idx)
69{
70 if (accessLatency == 0)
71 return;
72
73 unsigned int bank = mapIndexToBank(idx);
74 assert(bank < banks);
75
76 if(busyBanks[bank].endAccess >= curTick()) {
77 if (busyBanks[bank].startAccess == curTick() &&
78 busyBanks[bank].idx == idx) {
79 // this is the same reservation (can happen when
80 // e.g., reserve the same resource for read and write)
81 return; // OK
82 } else {
83 panic("BankedArray reservation error");
84 }
85 }
86
87 busyBanks[bank].idx = idx;
88 busyBanks[bank].startAccess = curTick();
89 busyBanks[bank].endAccess = curTick() +
90 (accessLatency-1) * m_ruby_system->clockPeriod();
91}
92
93unsigned int
69{
70 if (accessLatency == 0)
71 return;
72
73 unsigned int bank = mapIndexToBank(idx);
74 assert(bank < banks);
75
76 if(busyBanks[bank].endAccess >= curTick()) {
77 if (busyBanks[bank].startAccess == curTick() &&
78 busyBanks[bank].idx == idx) {
79 // this is the same reservation (can happen when
80 // e.g., reserve the same resource for read and write)
81 return; // OK
82 } else {
83 panic("BankedArray reservation error");
84 }
85 }
86
87 busyBanks[bank].idx = idx;
88 busyBanks[bank].startAccess = curTick();
89 busyBanks[bank].endAccess = curTick() +
90 (accessLatency-1) * m_ruby_system->clockPeriod();
91}
92
93unsigned int
94BankedArray::mapIndexToBank(int64 idx)
94BankedArray::mapIndexToBank(int64_t idx)
95{
96 if (banks == 1) {
97 return 0;
98 }
99 return idx % banks;
100}
95{
96 if (banks == 1) {
97 return 0;
98 }
99 return idx % banks;
100}