1/*
2 * Copyright 2018 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 * Authors: Gabe Black
28 */
29
30#include <sstream>
31#include <vector>
32
33#include "base/logging.hh"
34#include "base/types.hh"
35#include "python/pybind11/pybind.hh"
36#include "sim/core.hh"
37#include "systemc/core/python.hh"
38#include "systemc/core/time.hh"
39#include "systemc/ext/core/sc_main.hh"
40#include "systemc/ext/core/sc_time.hh"
41#include "systemc/ext/utils/sc_report_handler.hh"
42
43namespace sc_core
44{
45
46namespace
47{
48
49bool timeFixed = false;
50bool pythonReady = false;
51
52struct SetInfo
53{
54 SetInfo(::sc_core::sc_time *time, double d, ::sc_core::sc_time_unit tu) :
55 time(time), d(d), tu(tu)
56 {}
57
58 ::sc_core::sc_time *time;
59 double d;
60 ::sc_core::sc_time_unit tu;
61};
62std::vector<SetInfo> toSet;
63
64void
65setWork(sc_time *time, double d, ::sc_core::sc_time_unit tu)
66{
67 double scale = sc_gem5::TimeUnitScale[tu] * SimClock::Float::s;
68 // Accellera claims there is a linux bug, and that these next two
69 // lines work around them.
70 volatile double tmp = d * scale + 0.5;
71 *time = sc_time::from_value(static_cast<uint64_t>(tmp));
72}
73
74void
75fixTime()
76{
77 auto ticks = pybind11::module::import("m5.ticks");
78 auto fix_global_frequency = ticks.attr("fixGlobalFrequency");
79 fix_global_frequency();
80
81 for (auto &t: toSet)
82 setWork(t.time, t.d, t.tu);
83 toSet.clear();
84}
85
86void
87attemptToFixTime()
88{
89 // Only fix time once.
90 if (!timeFixed) {
91 timeFixed = true;
92
93 // If we've run, python is working and we haven't fixed time yet.
94 if (pythonReady)
95 fixTime();
96 }
97}
98
99void
100setGlobalFrequency(Tick ticks_per_second)
101{
102 auto ticks = pybind11::module::import("m5.ticks");
103 auto set_global_frequency = ticks.attr("setGlobalFrequency");
104 set_global_frequency(ticks_per_second);
105 fixTime();
106}
107
108void
109set(::sc_core::sc_time *time, double d, ::sc_core::sc_time_unit tu)
110{
111 if (d != 0)
112 attemptToFixTime();
113 if (pythonReady) {
114 // Time should be working. Set up this sc_time.
115 setWork(time, d, tu);
116 } else {
117 // Time isn't set up yet. Defer setting up this sc_time.
118 toSet.emplace_back(time, d, tu);
119 }
120}
121
122class TimeSetter : public ::sc_gem5::PythonReadyFunc
123{
124 public:
125 TimeSetter() : ::sc_gem5::PythonReadyFunc() {}
126
127 void
128 run() override
129 {
130 // Record that we've run and python/pybind should be usable.
131 pythonReady = true;
132
133 // If time is already fixed, let python know.
134 if (timeFixed)
135 fixTime();
136 }
137} timeSetter;
138
139double defaultUnit = 1.0e-9;
140
141} // anonymous namespace
142
143sc_time::sc_time() : val(0) {}
144
145sc_time::sc_time(double d, sc_time_unit tu)
146{
147 val = 0;
148 set(this, d, tu);
149}
150
151sc_time::sc_time(const sc_time &t)
152{
153 val = t.val;
154}
155
156sc_time::sc_time(double d, bool scale)
157{
158 double scaler = scale ? defaultUnit : SimClock::Float::Hz;
159 set(this, d * scaler, SC_SEC);
160}
161
162sc_time::sc_time(sc_dt::uint64 v, bool scale)
163{
164 double scaler = scale ? defaultUnit : SimClock::Float::Hz;
165 set(this, static_cast<double>(v) * scaler, SC_SEC);
166}
167
168sc_time &
169sc_time::operator = (const sc_time &t)
170{
171 val = t.val;
172 return *this;
173}
174
175sc_dt::uint64
176sc_time::value() const
177{
178 return val;
179}
180
181double
182sc_time::to_double() const
183{
184 return static_cast<double>(val);
185}
186double
187sc_time::to_seconds() const
188{
189 return to_double() * SimClock::Float::Hz;
190}
191
192const std::string
193sc_time::to_string() const
194{
195 std::ostringstream ss;
196 print(ss);
197 return ss.str();
198}
199
200bool
201sc_time::operator == (const sc_time &t) const
202{
203 return val == t.val;
204}
205
206bool
207sc_time::operator != (const sc_time &t) const
208{
209 return val != t.val;
210}
211
212bool
213sc_time::operator < (const sc_time &t) const
214{
215 return val < t.val;
216}
217
218bool
219sc_time::operator <= (const sc_time &t) const
220{
221 return val <= t.val;
222}
223
224bool
225sc_time::operator > (const sc_time &t) const
226{
227 return val > t.val;
228}
229
230bool
231sc_time::operator >= (const sc_time &t) const
232{
233 return val >= t.val;
234}
235
236sc_time &
237sc_time::operator += (const sc_time &t)
238{
239 val += t.val;
240 return *this;
241}
242
243sc_time &
244sc_time::operator -= (const sc_time &t)
245{
246 val -= t.val;
247 return *this;
248}
249
250sc_time &
251sc_time::operator *= (double d)
252{
253 val = static_cast<int64_t>(static_cast<double>(val) * d + 0.5);
254 return *this;
255}
256
257sc_time &
258sc_time::operator /= (double d)
259{
260 val = static_cast<int64_t>(static_cast<double>(val) / d + 0.5);
261 return *this;
262}
263
264void
265sc_time::print(std::ostream &os) const
266{
267 if (val == 0) {
268 os << "0 s";
269 } else {
270 Tick frequency = SimClock::Frequency;
271
272 // Shrink the frequency by scaling down the time period, ie converting
273 // it from cycles per second to cycles per millisecond, etc.
274 sc_time_unit tu = SC_SEC;
275 while (tu > 1 && (frequency % 1000 == 0)) {
276 tu = (sc_time_unit)((int)tu - 1);
277 frequency /= 1000;
278 }
279
280 // Convert the frequency into a period.
281 Tick period;
282 if (frequency > 1) {
283 tu = (sc_time_unit)((int)tu - 1);
284 period = 1000 / frequency;
285 } else {
286 period = frequency;
287 }
288
289 // Scale our integer value by the period.
290 uint64_t scaled = val * period;
291
292 // Shrink the scaled time value by increasing the size of the units
293 // it's measured by, avoiding fractional parts.
294 while (tu < SC_SEC && (scaled % 1000) == 0) {
295 tu = (sc_time_unit)((int)tu + 1);
296 scaled /= 1000;
297 }
298
299 os << scaled << ' ' << sc_gem5::TimeUnitNames[tu];
300 }
301}
302
303sc_time
304sc_time::from_value(sc_dt::uint64 u)
305{
306 if (u)
307 attemptToFixTime();
308 sc_time t;
309 t.val = u;
310 return t;
311}
312
313sc_time
314sc_time::from_seconds(double d)
315{
316 sc_time t;
317 set(&t, d, SC_SEC);
318 return t;
319}
320
321sc_time
322sc_time::from_string(const char *str)
323{
324 warn("%s not implemented.\n", __PRETTY_FUNCTION__);
325 return sc_time();
326}
327
328const sc_time
329operator + (const sc_time &a, const sc_time &b)
330{
331 return sc_time::from_value(a.value() + b.value());
332}
333
334const sc_time
335operator - (const sc_time &a, const sc_time &b)
336{
337 return sc_time::from_value(a.value() - b.value());
338}
339
340const sc_time
341operator * (const sc_time &t, double d)
342{
343 volatile double tmp = static_cast<double>(t.value()) * d + 0.5;
344 return sc_time::from_value(static_cast<int64_t>(tmp));
345}
346
347const sc_time
348operator * (double d, const sc_time &t)
349{
350 volatile double tmp = d * static_cast<double>(t.value()) + 0.5;
351 return sc_time::from_value(static_cast<int64_t>(tmp));
352}
353
354const sc_time
355operator / (const sc_time &t, double d)
356{
357 volatile double tmp = static_cast<double>(t.value()) / d + 0.5;
358 return sc_time::from_value(static_cast<int64_t>(tmp));
359}
360
361double
362operator / (const sc_time &t1, const sc_time &t2)
363{
364 return t1.to_double() / t2.to_double();
365}
366
367std::ostream &
368operator << (std::ostream &os, const sc_time &t)
369{
370 t.print(os);
371 return os;
372}
373
374const sc_time SC_ZERO_TIME;
375
376void
377sc_set_time_resolution(double d, sc_time_unit tu)
378{
379 if (d <= 0.0) {
380 SC_REPORT_ERROR("(E514) set time resolution failed",
381 "value not positive");
382 }
383 double dummy;
384 if (modf(log10(d), &dummy) != 0.0) {
385 SC_REPORT_ERROR("(E514) set time resolution failed",
386 "value not a power of ten");
387 }
388 if (sc_is_running()) {
389 SC_REPORT_ERROR("(E514) set time resolution failed",
390 "simulation running");
391 }
392 static bool specified = false;
393 if (specified) {
394 SC_REPORT_ERROR("(E514) set time resolution failed",
395 "already specified");
396 }
397 // This won't detect the timescale being fixed outside of systemc, but
398 // it's at least some protection.
399 if (timeFixed) {
400 SC_REPORT_ERROR("(E514) set time resolution failed",
401 "sc_time object(s) constructed");
402 }
403
404 double seconds = d * sc_gem5::TimeUnitScale[tu];
405 if (seconds < sc_gem5::TimeUnitScale[SC_FS]) {
406 SC_REPORT_ERROR("(E514) set time resolution failed",
407 "value smaller than 1 fs");
408 }
409
410 if (seconds > defaultUnit) {
411 SC_REPORT_WARNING(
412 "(W516) default time unit changed to time resolution", "");
413 defaultUnit = seconds;
414 }
415
416 // Get rid of fractional parts of d.
417 while (d < 1.0 && tu > SC_FS) {
418 d *= 1000;
419 tu = (sc_time_unit)(tu - 1);
420 }
421
422 Tick ticks_per_second =
423 sc_gem5::TimeUnitFrequency[tu] / static_cast<Tick>(d);
424 setGlobalFrequency(ticks_per_second);
425 specified = true;
426}
427
428sc_time
429sc_get_time_resolution()
430{
431 return sc_time::from_value(1);
432}
433
434const sc_time &
435sc_max_time()
436{
437 static const sc_time MaxScTime = sc_time::from_value(MaxTick);
438 return MaxScTime;
439}
440
441void
442sc_set_default_time_unit(double d, sc_time_unit tu)
443{
444 if (d < 0.0) {
445 SC_REPORT_ERROR("(E515) set default time unit failed",
446 "value not positive");
447 }
448 double dummy;
449 if (modf(log10(d), &dummy) != 0.0) {
450 SC_REPORT_ERROR("(E515) set default time unit failed",
451 "value not a power of ten");
452 }
453 if (sc_is_running()) {
454 SC_REPORT_ERROR("(E515) set default time unit failed",
455 "simulation running");
456 }
457 static bool specified = false;
458 if (specified) {
459 SC_REPORT_ERROR("(E515) set default time unit failed",
460 "already specified");
461 }
462 // This won't detect the timescale being fixed outside of systemc, but
463 // it's at least some protection.
464 if (timeFixed) {
465 SC_REPORT_ERROR("(E515) set default time unit failed",
466 "sc_time object(s) constructed");
467 }
468
469 // Normalize d to seconds.
470 defaultUnit = d * sc_gem5::TimeUnitScale[tu];
471 specified = true;
472
473 double resolution = SimClock::Float::Hz;
474 if (resolution == 0.0)
475 resolution = sc_gem5::TimeUnitScale[SC_PS];
476 if (defaultUnit < resolution) {
477 SC_REPORT_ERROR("(E515) set default time unit failed",
478 "value smaller than time resolution");
479 }
480}
481
482sc_time
483sc_get_default_time_unit()
484{
485 return sc_time(defaultUnit, SC_SEC);
486}
487
488sc_time_tuple::sc_time_tuple(const sc_time &)
489{
490 warn("%s not implemented.\n", __PRETTY_FUNCTION__);
491}
492
493bool
494sc_time_tuple::has_value() const
495{
496 warn("%s not implemented.\n", __PRETTY_FUNCTION__);
497 return false;
498}
499
500sc_dt::uint64
501sc_time_tuple::value() const
502{
503 warn("%s not implemented.\n", __PRETTY_FUNCTION__);
504 return 0;
505}
506
507const char *
508sc_time_tuple::unit_symbol() const
509{
510 warn("%s not implemented.\n", __PRETTY_FUNCTION__);
511 return "";
512}
513
514double
515sc_time_tuple::to_double() const
516{
517 warn("%s not implemented.\n", __PRETTY_FUNCTION__);
518 return 0.0;
519}
520
521std::string
522sc_time_tuple::to_string() const
523{
524 warn("%s not implemented.\n", __PRETTY_FUNCTION__);
525 return "";
526}
527
528} // namespace sc_core