1
2/*
3 * Copyright (c) 2006 The Regents of The University of Michigan
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are
8 * met: redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer;
10 * redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution;
13 * neither the name of the copyright holders nor the names of its
14 * contributors may be used to endorse or promote products derived from
15 * this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
20 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
21 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
23 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 *
29 * Authors: Ali Saidi
30 * Steve Reinhardt
31 */
32
33/**
34 * @file
35 * Definition of a simple bus bridge without buffering.
36 */
37
38#include <algorithm>
39
40#include "base/range_ops.hh"
41#include "base/trace.hh"
42#include "mem/bridge.hh"
43#include "params/Bridge.hh"
44
45Bridge::BridgePort::BridgePort(const std::string &_name,
46 Bridge *_bridge, BridgePort *_otherPort,
47 int _delay, int _nack_delay, int _req_limit,
48 int _resp_limit,
49 std::vector<Range<Addr> > filter_ranges)
50 : Port(_name, _bridge), bridge(_bridge), otherPort(_otherPort),
51 delay(_delay), nackDelay(_nack_delay), filterRanges(filter_ranges),
52 outstandingResponses(0), queuedRequests(0), inRetry(false),
53 reqQueueLimit(_req_limit), respQueueLimit(_resp_limit), sendEvent(this)
54{
55}
56
57Bridge::Bridge(Params *p)
58 : MemObject(p),
59 portA(p->name + "-portA", this, &portB, p->delay, p->nack_delay,
60 p->req_size_a, p->resp_size_a, p->filter_ranges_a),
61 portB(p->name + "-portB", this, &portA, p->delay, p->nack_delay,
62 p->req_size_b, p->resp_size_b, p->filter_ranges_b),
63 ackWrites(p->write_ack), _params(p)
64{
65 if (ackWrites)
66 panic("No support for acknowledging writes\n");
67}
68
69Port *
70Bridge::getPort(const std::string &if_name, int idx)
71{
72 BridgePort *port;
73
74 if (if_name == "side_a")
75 port = &portA;
76 else if (if_name == "side_b")
77 port = &portB;
78 else
79 return NULL;
80
81 if (port->getPeer() != NULL && !port->getPeer()->isDefaultPort())
82 panic("bridge side %s already connected to %s.",
83 if_name, port->getPeer()->name());
84 return port;
85}
86
87
88void
89Bridge::init()
90{
91 // Make sure that both sides are connected to.
92 if (!portA.isConnected() || !portB.isConnected())
93 fatal("Both ports of bus bridge are not connected to a bus.\n");
94
95 if (portA.peerBlockSize() != portB.peerBlockSize())
96 fatal("port A size %d, port B size %d \n " \
97 "Busses don't have the same block size... Not supported.\n",
98 portA.peerBlockSize(), portB.peerBlockSize());
99}
100
101bool
102Bridge::BridgePort::respQueueFull()
103{
104 assert(outstandingResponses >= 0 && outstandingResponses <= respQueueLimit);
105 return outstandingResponses >= respQueueLimit;
106}
107
108bool
109Bridge::BridgePort::reqQueueFull()
110{
111 assert(queuedRequests >= 0 && queuedRequests <= reqQueueLimit);
112 return queuedRequests >= reqQueueLimit;
113}
114
115/** Function called by the port when the bus is receiving a Timing
116 * transaction.*/
117bool
118Bridge::BridgePort::recvTiming(PacketPtr pkt)
119{
120 DPRINTF(BusBridge, "recvTiming: src %d dest %d addr 0x%x\n",
121 pkt->getSrc(), pkt->getDest(), pkt->getAddr());
122
123 DPRINTF(BusBridge, "Local queue size: %d outreq: %d outresp: %d\n",
124 sendQueue.size(), queuedRequests, outstandingResponses);
125 DPRINTF(BusBridge, "Remote queue size: %d outreq: %d outresp: %d\n",
126 otherPort->sendQueue.size(), otherPort->queuedRequests,
127 otherPort->outstandingResponses);
128
129 if (pkt->isRequest() && otherPort->reqQueueFull()) {
130 DPRINTF(BusBridge, "Remote queue full, nacking\n");
131 nackRequest(pkt);
132 return true;
133 }
134
135 if (pkt->needsResponse()) {
136 if (respQueueFull()) {
137 DPRINTF(BusBridge, "Local queue full, no space for response, nacking\n");
138 DPRINTF(BusBridge, "queue size: %d outreq: %d outstanding resp: %d\n",
139 sendQueue.size(), queuedRequests, outstandingResponses);
140 nackRequest(pkt);
141 return true;
142 } else {
143 DPRINTF(BusBridge, "Request Needs response, reserving space\n");
144 ++outstandingResponses;
145 }
146 }
147
148 otherPort->queueForSendTiming(pkt);
149
150 return true;
151}
152
153void
154Bridge::BridgePort::nackRequest(PacketPtr pkt)
155{
156 // Nack the packet
157 pkt->makeTimingResponse();
158 pkt->setNacked();
159
160 //put it on the list to send
| 1
2/*
3 * Copyright (c) 2006 The Regents of The University of Michigan
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions are
8 * met: redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer;
10 * redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution;
13 * neither the name of the copyright holders nor the names of its
14 * contributors may be used to endorse or promote products derived from
15 * this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
20 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
21 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
23 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 *
29 * Authors: Ali Saidi
30 * Steve Reinhardt
31 */
32
33/**
34 * @file
35 * Definition of a simple bus bridge without buffering.
36 */
37
38#include <algorithm>
39
40#include "base/range_ops.hh"
41#include "base/trace.hh"
42#include "mem/bridge.hh"
43#include "params/Bridge.hh"
44
45Bridge::BridgePort::BridgePort(const std::string &_name,
46 Bridge *_bridge, BridgePort *_otherPort,
47 int _delay, int _nack_delay, int _req_limit,
48 int _resp_limit,
49 std::vector<Range<Addr> > filter_ranges)
50 : Port(_name, _bridge), bridge(_bridge), otherPort(_otherPort),
51 delay(_delay), nackDelay(_nack_delay), filterRanges(filter_ranges),
52 outstandingResponses(0), queuedRequests(0), inRetry(false),
53 reqQueueLimit(_req_limit), respQueueLimit(_resp_limit), sendEvent(this)
54{
55}
56
57Bridge::Bridge(Params *p)
58 : MemObject(p),
59 portA(p->name + "-portA", this, &portB, p->delay, p->nack_delay,
60 p->req_size_a, p->resp_size_a, p->filter_ranges_a),
61 portB(p->name + "-portB", this, &portA, p->delay, p->nack_delay,
62 p->req_size_b, p->resp_size_b, p->filter_ranges_b),
63 ackWrites(p->write_ack), _params(p)
64{
65 if (ackWrites)
66 panic("No support for acknowledging writes\n");
67}
68
69Port *
70Bridge::getPort(const std::string &if_name, int idx)
71{
72 BridgePort *port;
73
74 if (if_name == "side_a")
75 port = &portA;
76 else if (if_name == "side_b")
77 port = &portB;
78 else
79 return NULL;
80
81 if (port->getPeer() != NULL && !port->getPeer()->isDefaultPort())
82 panic("bridge side %s already connected to %s.",
83 if_name, port->getPeer()->name());
84 return port;
85}
86
87
88void
89Bridge::init()
90{
91 // Make sure that both sides are connected to.
92 if (!portA.isConnected() || !portB.isConnected())
93 fatal("Both ports of bus bridge are not connected to a bus.\n");
94
95 if (portA.peerBlockSize() != portB.peerBlockSize())
96 fatal("port A size %d, port B size %d \n " \
97 "Busses don't have the same block size... Not supported.\n",
98 portA.peerBlockSize(), portB.peerBlockSize());
99}
100
101bool
102Bridge::BridgePort::respQueueFull()
103{
104 assert(outstandingResponses >= 0 && outstandingResponses <= respQueueLimit);
105 return outstandingResponses >= respQueueLimit;
106}
107
108bool
109Bridge::BridgePort::reqQueueFull()
110{
111 assert(queuedRequests >= 0 && queuedRequests <= reqQueueLimit);
112 return queuedRequests >= reqQueueLimit;
113}
114
115/** Function called by the port when the bus is receiving a Timing
116 * transaction.*/
117bool
118Bridge::BridgePort::recvTiming(PacketPtr pkt)
119{
120 DPRINTF(BusBridge, "recvTiming: src %d dest %d addr 0x%x\n",
121 pkt->getSrc(), pkt->getDest(), pkt->getAddr());
122
123 DPRINTF(BusBridge, "Local queue size: %d outreq: %d outresp: %d\n",
124 sendQueue.size(), queuedRequests, outstandingResponses);
125 DPRINTF(BusBridge, "Remote queue size: %d outreq: %d outresp: %d\n",
126 otherPort->sendQueue.size(), otherPort->queuedRequests,
127 otherPort->outstandingResponses);
128
129 if (pkt->isRequest() && otherPort->reqQueueFull()) {
130 DPRINTF(BusBridge, "Remote queue full, nacking\n");
131 nackRequest(pkt);
132 return true;
133 }
134
135 if (pkt->needsResponse()) {
136 if (respQueueFull()) {
137 DPRINTF(BusBridge, "Local queue full, no space for response, nacking\n");
138 DPRINTF(BusBridge, "queue size: %d outreq: %d outstanding resp: %d\n",
139 sendQueue.size(), queuedRequests, outstandingResponses);
140 nackRequest(pkt);
141 return true;
142 } else {
143 DPRINTF(BusBridge, "Request Needs response, reserving space\n");
144 ++outstandingResponses;
145 }
146 }
147
148 otherPort->queueForSendTiming(pkt);
149
150 return true;
151}
152
153void
154Bridge::BridgePort::nackRequest(PacketPtr pkt)
155{
156 // Nack the packet
157 pkt->makeTimingResponse();
158 pkt->setNacked();
159
160 //put it on the list to send
|