1/*
2 * Copyright 2019 Google, Inc.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions are
6 * met: redistributions of source code must retain the above copyright
7 * notice, this list of conditions and the following disclaimer;
8 * redistributions in binary form must reproduce the above copyright
9 * notice, this list of conditions and the following disclaimer in the
10 * documentation and/or other materials provided with the distribution;
11 * neither the name of the copyright holders nor the names of its
12 * contributors may be used to endorse or promote products derived from
13 * this software without specific prior written permission.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
18 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
19 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
20 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
21 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
25 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 *
27 * Copyright (c) 2015, University of Kaiserslautern
28 * Copyright (c) 2016, Dresden University of Technology (TU Dresden)
29 * All rights reserved.
30 *
31 * Redistribution and use in source and binary forms, with or without
32 * modification, are permitted provided that the following conditions are
33 * met:
34 *
35 * 1. Redistributions of source code must retain the above copyright notice,
36 * this list of conditions and the following disclaimer.
37 *
38 * 2. Redistributions in binary form must reproduce the above copyright
39 * notice, this list of conditions and the following disclaimer in the
40 * documentation and/or other materials provided with the distribution.
41 *
42 * 3. Neither the name of the copyright holder nor the names of its
43 * contributors may be used to endorse or promote products derived from
44 * this software without specific prior written permission.
45 *
46 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
47 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
48 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
49 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER
50 * OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
51 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
52 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
53 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
54 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
55 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
56 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
57 *
58 * Authors: Gabe Black
59 * Matthias Jung
60 * Abdul Mutaal Ahmad
61 * Christian Menard
62 */
63
64#include "systemc/tlm_bridge/gem5_to_tlm.hh"
65
66#include "params/Gem5ToTlmBridge32.hh"
67#include "params/Gem5ToTlmBridge64.hh"
68#include "sim/system.hh"
69#include "systemc/tlm_bridge/sc_ext.hh"
70#include "systemc/tlm_bridge/sc_mm.hh"
71
72namespace sc_gem5
73{
74
75/**
76 * Instantiate a tlm memory manager that takes care about all the
77 * tlm transactions in the system.
78 */
79Gem5SystemC::MemoryManager mm;
80
81/**
82 * Convert a gem5 packet to a TLM payload by copying all the relevant
83 * information to a previously allocated tlm payload
84 */
85void
86packet2payload(PacketPtr packet, tlm::tlm_generic_payload &trans)
87{
88 trans.set_address(packet->getAddr());
89
90 /* Check if this transaction was allocated by mm */
91 sc_assert(trans.has_mm());
92
93 unsigned int size = packet->getSize();
94 unsigned char *data = packet->getPtr<unsigned char>();
95
96 trans.set_data_length(size);
97 trans.set_streaming_width(size);
98 trans.set_data_ptr(data);
99
100 if (packet->isRead()) {
101 trans.set_command(tlm::TLM_READ_COMMAND);
102 } else if (packet->isInvalidate()) {
103 /* Do nothing */
104 } else if (packet->isWrite()) {
105 trans.set_command(tlm::TLM_WRITE_COMMAND);
106 } else {
107 SC_REPORT_FATAL("Gem5ToTlmBridge", "No R/W packet");
108 }
109}
110
111template <unsigned int BITWIDTH>
112void
110Gem5ToTlmBridge::pec(Gem5SystemC::PayloadEvent<Gem5ToTlmBridge> *pe,
113Gem5ToTlmBridge<BITWIDTH>::pec(
114 Gem5SystemC::PayloadEvent<Gem5ToTlmBridge<BITWIDTH>> *pe,
115 tlm::tlm_generic_payload &trans, const tlm::tlm_phase &phase)
116{
117 sc_core::sc_time delay;
118
119 if (phase == tlm::END_REQ ||
120 (&trans == blockingRequest && phase == tlm::BEGIN_RESP)) {
121 sc_assert(&trans == blockingRequest);
122 blockingRequest = nullptr;
123
124 // Did another request arrive while blocked, schedule a retry.
125 if (needToSendRequestRetry) {
126 needToSendRequestRetry = false;
127 bsp.sendRetryReq();
128 }
129 }
130 if (phase == tlm::BEGIN_RESP) {
131 auto &extension = Gem5SystemC::Gem5Extension::getExtension(trans);
132 auto packet = extension.getPacket();
133
134 sc_assert(!blockingResponse);
135
136 bool need_retry = false;
137
138 /*
139 * If the packet was piped through and needs a response, we don't need
140 * to touch the packet and can forward it directly as a response.
141 * Otherwise, we need to make a response and send the transformed
142 * packet.
143 */
144 if (extension.isPipeThrough()) {
145 if (packet->isResponse()) {
146 need_retry = !bsp.sendTimingResp(packet);
147 }
148 } else if (packet->needsResponse()) {
149 packet->makeResponse();
150 need_retry = !bsp.sendTimingResp(packet);
151 }
152
153 if (need_retry) {
154 blockingResponse = &trans;
155 } else {
156 if (phase == tlm::BEGIN_RESP) {
157 // Send END_RESP and we're finished:
158 tlm::tlm_phase fw_phase = tlm::END_RESP;
159 sc_core::sc_time delay = sc_core::SC_ZERO_TIME;
160 socket->nb_transport_fw(trans, fw_phase, delay);
161 // Release the transaction with all the extensions.
162 trans.release();
163 }
164 }
165 }
166 delete pe;
167}
168
169// Similar to TLM's blocking transport (LT)
170template <unsigned int BITWIDTH>
171Tick
167Gem5ToTlmBridge::recvAtomic(PacketPtr packet)
172Gem5ToTlmBridge<BITWIDTH>::recvAtomic(PacketPtr packet)
173{
174 panic_if(packet->cacheResponding(),
175 "Should not see packets where cache is responding");
176
177 panic_if(!(packet->isRead() || packet->isWrite()),
178 "Should only see read and writes at TLM memory\n");
179
180 sc_core::sc_time delay = sc_core::SC_ZERO_TIME;
181
182 // Prepare the transaction.
183 tlm::tlm_generic_payload *trans = mm.allocate();
184 trans->acquire();
185 packet2payload(packet, *trans);
186
187 // Attach the packet pointer to the TLM transaction to keep track.
188 auto *extension = new Gem5SystemC::Gem5Extension(packet);
189 trans->set_auto_extension(extension);
190
191 // Execute b_transport:
192 if (packet->cmd == MemCmd::SwapReq) {
193 SC_REPORT_FATAL("Gem5ToTlmBridge", "SwapReq not supported");
194 } else if (packet->isRead()) {
195 socket->b_transport(*trans, delay);
196 } else if (packet->isInvalidate()) {
197 // do nothing
198 } else if (packet->isWrite()) {
199 socket->b_transport(*trans, delay);
200 } else {
201 SC_REPORT_FATAL("Gem5ToTlmBridge", "Typo of request not supported");
202 }
203
204 if (packet->needsResponse()) {
205 packet->makeResponse();
206 }
207
208 trans->release();
209
210 return delay.value();
211}
212
213template <unsigned int BITWIDTH>
214void
209Gem5ToTlmBridge::recvFunctionalSnoop(PacketPtr packet)
215Gem5ToTlmBridge<BITWIDTH>::recvFunctionalSnoop(PacketPtr packet)
216{
217 // Snooping should be implemented with tlm_dbg_transport.
218 SC_REPORT_FATAL("Gem5ToTlmBridge",
219 "unimplemented func.: recvFunctionalSnoop");
220}
221
222// Similar to TLM's non-blocking transport (AT).
223template <unsigned int BITWIDTH>
224bool
218Gem5ToTlmBridge::recvTimingReq(PacketPtr packet)
225Gem5ToTlmBridge<BITWIDTH>::recvTimingReq(PacketPtr packet)
226{
227 panic_if(packet->cacheResponding(),
228 "Should not see packets where cache is responding");
229
230 panic_if(!(packet->isRead() || packet->isWrite()),
231 "Should only see read and writes at TLM memory\n");
232
233
234 // We should never get a second request after noting that a retry is
235 // required.
236 sc_assert(!needToSendRequestRetry);
237
238 // Remember if a request comes in while we're blocked so that a retry
239 // can be sent to gem5.
240 if (blockingRequest) {
241 needToSendRequestRetry = true;
242 return false;
243 }
244
245 /*
246 * NOTE: normal tlm is blocking here. But in our case we return false
247 * and tell gem5 when a retry can be done. This is the main difference
248 * in the protocol:
249 * if (requestInProgress)
250 * {
251 * wait(endRequestEvent);
252 * }
253 * requestInProgress = trans;
254 */
255
256 // Prepare the transaction.
257 tlm::tlm_generic_payload *trans = mm.allocate();
258 trans->acquire();
259 packet2payload(packet, *trans);
260
261 // Attach the packet pointer to the TLM transaction to keep track.
262 auto *extension = new Gem5SystemC::Gem5Extension(packet);
263 trans->set_auto_extension(extension);
264
265 /*
266 * Pay for annotated transport delays.
267 *
268 * The header delay marks the point in time, when the packet first is seen
269 * by the transactor. This is the point in time when the transactor needs
270 * to send the BEGIN_REQ to the SystemC world.
271 *
272 * NOTE: We drop the payload delay here. Normally, the receiver would be
273 * responsible for handling the payload delay. In this case, however,
274 * the receiver is a SystemC module and has no notion of the gem5
275 * transport protocol and we cannot simply forward the
276 * payload delay to the receiving module. Instead, we expect the
277 * receiving SystemC module to model the payload delay by deferring
278 * the END_REQ. This could lead to incorrect delays, if the XBar
279 * payload delay is longer than the time the receiver needs to accept
280 * the request (time between BEGIN_REQ and END_REQ).
281 *
282 * TODO: We could detect the case described above by remembering the
283 * payload delay and comparing it to the time between BEGIN_REQ and
284 * END_REQ. Then, a warning should be printed.
285 */
286 auto delay = sc_core::sc_time::from_value(packet->payloadDelay);
287 // Reset the delays
288 packet->payloadDelay = 0;
289 packet->headerDelay = 0;
290
291 // Starting TLM non-blocking sequence (AT) Refer to IEEE1666-2011 SystemC
292 // Standard Page 507 for a visualisation of the procedure.
293 tlm::tlm_phase phase = tlm::BEGIN_REQ;
294 tlm::tlm_sync_enum status;
295 status = socket->nb_transport_fw(*trans, phase, delay);
296 // Check returned value:
297 if (status == tlm::TLM_ACCEPTED) {
298 sc_assert(phase == tlm::BEGIN_REQ);
299 // Accepted but is now blocking until END_REQ (exclusion rule).
300 blockingRequest = trans;
301 } else if (status == tlm::TLM_UPDATED) {
302 // The Timing annotation must be honored:
303 sc_assert(phase == tlm::END_REQ || phase == tlm::BEGIN_RESP);
304
305 auto *pe = new Gem5SystemC::PayloadEvent<Gem5ToTlmBridge>(
306 *this, &Gem5ToTlmBridge::pec, "PEQ");
307 Tick nextEventTick = curTick() + delay.value();
308 system->wakeupEventQueue(nextEventTick);
309 system->schedule(pe, nextEventTick);
310 } else if (status == tlm::TLM_COMPLETED) {
311 // Transaction is over nothing has do be done.
312 sc_assert(phase == tlm::END_RESP);
313 trans->release();
314 }
315
316 return true;
317}
318
319template <unsigned int BITWIDTH>
320bool
313Gem5ToTlmBridge::recvTimingSnoopResp(PacketPtr packet)
321Gem5ToTlmBridge<BITWIDTH>::recvTimingSnoopResp(PacketPtr packet)
322{
323 // Snooping should be implemented with tlm_dbg_transport.
324 SC_REPORT_FATAL("Gem5ToTlmBridge",
325 "unimplemented func.: recvTimingSnoopResp");
326 return false;
327}
328
329template <unsigned int BITWIDTH>
330bool
322Gem5ToTlmBridge::tryTiming(PacketPtr packet)
331Gem5ToTlmBridge<BITWIDTH>::tryTiming(PacketPtr packet)
332{
333 panic("tryTiming(PacketPtr) isn't implemented.");
334}
335
336template <unsigned int BITWIDTH>
337void
328Gem5ToTlmBridge::recvRespRetry()
338Gem5ToTlmBridge<BITWIDTH>::recvRespRetry()
339{
340 /* Retry a response */
341 sc_assert(blockingResponse);
342
343 tlm::tlm_generic_payload *trans = blockingResponse;
344 blockingResponse = nullptr;
345 PacketPtr packet =
346 Gem5SystemC::Gem5Extension::getExtension(trans).getPacket();
347
348 bool need_retry = !bsp.sendTimingResp(packet);
349
350 sc_assert(!need_retry);
351
352 sc_core::sc_time delay = sc_core::SC_ZERO_TIME;
353 tlm::tlm_phase phase = tlm::END_RESP;
354 socket->nb_transport_fw(*trans, phase, delay);
355 // Release transaction with all the extensions
356 trans->release();
357}
358
359// Similar to TLM's debug transport.
360template <unsigned int BITWIDTH>
361void
351Gem5ToTlmBridge::recvFunctional(PacketPtr packet)
362Gem5ToTlmBridge<BITWIDTH>::recvFunctional(PacketPtr packet)
363{
364 // Prepare the transaction.
365 tlm::tlm_generic_payload *trans = mm.allocate();
366 trans->acquire();
367 packet2payload(packet, *trans);
368
369 // Attach the packet pointer to the TLM transaction to keep track.
370 auto *extension = new Gem5SystemC::Gem5Extension(packet);
371 trans->set_auto_extension(extension);
372
373 /* Execute Debug Transport: */
374 unsigned int bytes = socket->transport_dbg(*trans);
375 if (bytes != trans->get_data_length()) {
376 SC_REPORT_FATAL("Gem5ToTlmBridge",
377 "debug transport was not completed");
378 }
379
380 trans->release();
381}
382
383template <unsigned int BITWIDTH>
384tlm::tlm_sync_enum
373Gem5ToTlmBridge::nb_transport_bw(tlm::tlm_generic_payload &trans,
385Gem5ToTlmBridge<BITWIDTH>::nb_transport_bw(tlm::tlm_generic_payload &trans,
386 tlm::tlm_phase &phase, sc_core::sc_time &delay)
387{
388 auto *pe = new Gem5SystemC::PayloadEvent<Gem5ToTlmBridge>(
389 *this, &Gem5ToTlmBridge::pec, "PE");
390 Tick nextEventTick = curTick() + delay.value();
391 system->wakeupEventQueue(nextEventTick);
392 system->schedule(pe, nextEventTick);
393 return tlm::TLM_ACCEPTED;
394}
395
384Gem5ToTlmBridge::Gem5ToTlmBridge(
396template <unsigned int BITWIDTH>
397Gem5ToTlmBridge<BITWIDTH>::Gem5ToTlmBridge(
398 Params *params, const sc_core::sc_module_name &mn) :
386 sc_core::sc_module(mn), bsp(std::string(name()) + ".gem5", *this),
399 Gem5ToTlmBridgeBase(mn), bsp(std::string(name()) + ".gem5", *this),
400 socket("tlm_socket"),
401 wrapper(socket, std::string(name()) + ".tlm", InvalidPortID),
402 system(params->system), blockingRequest(nullptr),
403 needToSendRequestRetry(false), blockingResponse(nullptr),
404 addrRanges(params->addr_ranges.begin(), params->addr_ranges.end())
405{
406}
407
408template <unsigned int BITWIDTH>
409::Port &
396Gem5ToTlmBridge::gem5_getPort(const std::string &if_name, int idx)
410Gem5ToTlmBridge<BITWIDTH>::gem5_getPort(const std::string &if_name, int idx)
411{
412 if (if_name == "gem5")
413 return bsp;
414 else if (if_name == "tlm")
415 return wrapper;
416
417 return sc_core::sc_module::gem5_getPort(if_name, idx);
418}
419
420template <unsigned int BITWIDTH>
421void
407Gem5ToTlmBridge::before_end_of_elaboration()
422Gem5ToTlmBridge<BITWIDTH>::before_end_of_elaboration()
423{
424 bsp.sendRangeChange();
425
426 socket.register_nb_transport_bw(this, &Gem5ToTlmBridge::nb_transport_bw);
427 sc_core::sc_module::before_end_of_elaboration();
428}
429
430} // namespace sc_gem5
431
417sc_gem5::Gem5ToTlmBridge *
418Gem5ToTlmBridgeParams::create()
432sc_gem5::Gem5ToTlmBridge<32> *
433Gem5ToTlmBridge32Params::create()
434{
420 return new sc_gem5::Gem5ToTlmBridge(
435 return new sc_gem5::Gem5ToTlmBridge<32>(
436 this, sc_core::sc_module_name(name.c_str()));
437}
438
439sc_gem5::Gem5ToTlmBridge<64> *
440Gem5ToTlmBridge64Params::create()
441{
442 return new sc_gem5::Gem5ToTlmBridge<64>(
443 this, sc_core::sc_module_name(name.c_str()));
444}