1/*
2 * Copyright (c) 2012-2014 ARM Limited
3 * All rights reserved
4 *
5 * The license below extends only to copyright in the software and shall
6 * not be construed as granting a license to any other intellectual
7 * property including but not limited to intellectual property relating
8 * to a hardware implementation of the functionality of the software
9 * licensed hereunder. You may use the software subject to the license
10 * terms below provided that you ensure that this notice is replicated
11 * unmodified and in its entirety in all distributions of the software,
12 * modified or unmodified, in source code or in binary form.
13 *
14 * Redistribution and use in source and binary forms, with or without
15 * modification, are permitted provided that the following conditions are
16 * met: redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer;
18 * redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution;
21 * neither the name of the copyright holders nor the names of its
22 * contributors may be used to endorse or promote products derived from
23 * this software without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
26 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
28 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
29 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
31 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
35 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 *
37 * Authors: Andrew Bardsley
38 */
39
40#include <cctype>
41#include <iomanip>
42
43#include "debug/ExternalPort.hh"
44#include "mem/external_slave.hh"
45
46/** Implement a `stub' port which just responds to requests by printing
47 * a message. The stub port can be used to configure and test a system
48 * where the external port is used for a peripheral before connecting
49 * the external port */
50class StubSlavePort : public ExternalSlave::Port
51{
52 public:
53 class ResponseEvent : public Event
54 {
55 public:
56 StubSlavePort &owner;
57
58 ResponseEvent(StubSlavePort &owner_) : owner(owner_) { }
59
60 void process();
61 };
62
63 ResponseEvent responseEvent;
64
65 /** Stub can handle a single request at a time. This will be
66 * NULL when no packet is in flight */
67 PacketPtr responsePacket;
68
69 /** Received a new request while processing a first. Need to ask for
70 * a retry after completing this packet */
71 bool mustRetry;
72
73 StubSlavePort(const std::string &name_,
74 ExternalSlave &owner_) :
75 ExternalSlave::Port(name_, owner_),
76 responseEvent(*this), responsePacket(NULL), mustRetry(false)
77 { }
78
79 Tick recvAtomic(PacketPtr packet);
80 void recvFunctional(PacketPtr packet);
81 bool recvTimingReq(PacketPtr packet);
82 bool recvTimingSnoopResp(PacketPtr packet);
83 void recvRespRetry();
84 void recvFunctionalSnoop(PacketPtr packet);
85};
86
87class StubSlavePortHandler : public
88 ExternalSlave::Handler
89{
90 public:
91 ExternalSlave::Port *getExternalPort(
92 const std::string &name_,
93 ExternalSlave &owner,
94 const std::string &port_data)
95 {
96 StringWrap name(name_);
97
98 DPRINTF(ExternalPort, "finding stub port '%s'\n", port_data);
99 return new StubSlavePort(name_, owner);
100 }
101};
102
103Tick
104StubSlavePort::recvAtomic(PacketPtr packet)
105{
106 if (DTRACE(ExternalPort)) {
107 unsigned int M5_VAR_USED size = packet->getSize();
108
109 DPRINTF(ExternalPort, "StubSlavePort: recvAtomic a: 0x%x size: %d"
110 " data: ...\n", packet->getAddr(), size);
111 DDUMP(ExternalPort, packet->getConstPtr<uint8_t>(), size);
112 }
113
114 return 0;
115}
116
117void
118StubSlavePort::recvFunctional(PacketPtr packet)
119{
120 recvAtomic(packet);
121}
122
123void
124StubSlavePort::ResponseEvent::process()
125{
126 owner.responsePacket->makeResponse();
127 owner.responsePacket->headerDelay = 0;
128 owner.responsePacket->payloadDelay = 0;
129
130 if (owner.sendTimingResp(owner.responsePacket)) {
131 owner.responsePacket = NULL;
132
133 if (owner.mustRetry)
134 owner.sendRetryReq();
135 owner.mustRetry = false;
136 }
137}
138
139bool
140StubSlavePort::recvTimingReq(PacketPtr packet)
141{
142 if (responsePacket) {
143 mustRetry = true;
144
145 return false;
146 } else {
147 recvAtomic(packet);
148
149 responsePacket = packet;
150 owner.schedule(responseEvent, curTick());
151
152 return true;
153 }
154}
155
156bool
157StubSlavePort::recvTimingSnoopResp(PacketPtr packet)
158{
159 fatal("StubSlavePort: function: %s\n", __func__);
160 return false;
161}
162
163void
164StubSlavePort::recvRespRetry()
165{
166 assert(responsePacket);
167 /* Stub handles only one response at a time so responseEvent should never
168 * be scheduled at this point. Retrys shouldn't need to schedule, we
169 * can safely send the response here */
170 responseEvent.process();
171}
172
173void
174StubSlavePort::recvFunctionalSnoop(PacketPtr packet)
175{
176 fatal("StubSlavePort: unimplemented function: %s\n", __func__);
177}
178
179std::map<std::string, ExternalSlave::Handler *>
180 ExternalSlave::portHandlers;
181
182AddrRangeList
183ExternalSlave::Port::getAddrRanges() const
184{
185 return owner.addrRanges;
186}
187
188ExternalSlave::ExternalSlave(ExternalSlaveParams *params) :
189 MemObject(params),
190 externalPort(NULL),
191 portName(params->name + ".port"),
192 portType(params->port_type),
193 portData(params->port_data),
194 addrRanges(params->addr_ranges.begin(), params->addr_ranges.end())
195{
196 /* Register the stub handler if it hasn't already been registered */
197 if (portHandlers.find("stub") == portHandlers.end())
198 registerHandler("stub", new StubSlavePortHandler);
199}
200
201BaseSlavePort &
202ExternalSlave::getSlavePort(const std::string &if_name,
203 PortID idx)
204{
205 if (if_name == "port") {
206 DPRINTF(ExternalPort, "Trying to bind external port: %s %s\n",
207 portType, portName);
208
209 if (!externalPort) {
210 auto handlerIter = portHandlers.find(portType);
211
212 if (handlerIter == portHandlers.end())
213 fatal("Can't find port handler type '%s'\n", portType);
214
215 externalPort = portHandlers[portType]->getExternalPort(portName,
216 *this, portData);
217
218 if (!externalPort) {
219 fatal("%s: Can't find external port type: %s"
220 " port_data: '%s'\n", portName, portType, portData);
221 }
222 }
223 return *externalPort;
224 } else {
225 return MemObject::getSlavePort(if_name, idx);
226 }
227}
228
229void
230ExternalSlave::init()
231{
232 if (!externalPort) {
233 fatal("ExternalSlave %s: externalPort not set!\n", name());
234 } else if (!externalPort->isConnected()) {
235 fatal("ExternalSlave %s is unconnected!\n", name());
236 } else {
237 externalPort->sendRangeChange();
238 }
239}
240
241ExternalSlave *
242ExternalSlaveParams::create()
243{
244 return new ExternalSlave(this);
245}
246
247void
248ExternalSlave::registerHandler(const std::string &handler_name,
249 Handler *handler)
250{
251 portHandlers[handler_name] = handler;
252}