1/*
2 * Copyright (c) 2010-2013 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: Ali Saidi
38 * Geoffrey Blake
39 */
40
41#include "base/intmath.hh"
42#include "base/trace.hh"
43#include "debug/Checkpoint.hh"
44#include "debug/Timer.hh"
45#include "dev/arm/base_gic.hh"
46#include "dev/arm/timer_cpulocal.hh"
47#include "mem/packet.hh"
48#include "mem/packet_access.hh"
49
50CpuLocalTimer::CpuLocalTimer(Params *p)
51 : BasicPioDevice(p, 0x38), gic(p->gic)
52{
53 // Initialize the timer registers for each per cpu timer
54 for (int i = 0; i < CPU_MAX; i++) {
55 std::stringstream oss;
56 oss << name() << ".timer" << i;
57 localTimer[i]._name = oss.str();
58 localTimer[i].parent = this;
59 localTimer[i].intNumTimer = p->int_num_timer;
60 localTimer[i].intNumWatchdog = p->int_num_watchdog;
61 localTimer[i].cpuNum = i;
62 }
63}
64
65CpuLocalTimer::Timer::Timer()
66 : timerControl(0x0), watchdogControl(0x0), rawIntTimer(false), rawIntWatchdog(false),
67 rawResetWatchdog(false), watchdogDisableReg(0x0), pendingIntTimer(false), pendingIntWatchdog(false),
68 timerLoadValue(0x0), watchdogLoadValue(0x0), timerZeroEvent(this), watchdogZeroEvent(this)
69{
70}
71
72Tick
73CpuLocalTimer::read(PacketPtr pkt)
74{
75 assert(pkt->getAddr() >= pioAddr && pkt->getAddr() < pioAddr + pioSize);
76 assert(pkt->getSize() == 4);
77 Addr daddr = pkt->getAddr() - pioAddr;
78 pkt->allocate();
79 int cpu_id = pkt->req->contextId();
80 DPRINTF(Timer, "Reading from CpuLocalTimer at offset: %#x\n", daddr);
81 assert(cpu_id >= 0);
82 assert(cpu_id < CPU_MAX);
83
84 if (daddr < Timer::Size)
85 localTimer[cpu_id].read(pkt, daddr);
86 else
87 panic("Tried to read CpuLocalTimer at offset %#x that doesn't exist\n", daddr);
88 pkt->makeAtomicResponse();
89 return pioDelay;
90}
91
92
93void
94CpuLocalTimer::Timer::read(PacketPtr pkt, Addr daddr)
95{
96 DPRINTF(Timer, "Reading from CpuLocalTimer at offset: %#x\n", daddr);
97 Tick time;
98
99 switch(daddr) {
100 case TimerLoadReg:
101 pkt->set<uint32_t>(timerLoadValue);
102 break;
103 case TimerCounterReg:
104 DPRINTF(Timer, "Event schedule for timer %d, clock=%d, prescale=%d\n",
105 timerZeroEvent.when(), parent->clockPeriod(),
106 timerControl.prescalar);
107 time = timerZeroEvent.when() - curTick();
108 time = time / parent->clockPeriod() /
109 power(16, timerControl.prescalar);
110 DPRINTF(Timer, "-- returning counter at %d\n", time);
111 pkt->set<uint32_t>(time);
112 break;
113 case TimerControlReg:
114 pkt->set<uint32_t>(timerControl);
115 break;
116 case TimerIntStatusReg:
117 pkt->set<uint32_t>(rawIntTimer);
118 break;
119 case WatchdogLoadReg:
120 pkt->set<uint32_t>(watchdogLoadValue);
121 break;
122 case WatchdogCounterReg:
123 DPRINTF(Timer,
124 "Event schedule for watchdog %d, clock=%d, prescale=%d\n",
125 watchdogZeroEvent.when(), parent->clockPeriod(),
126 watchdogControl.prescalar);
127 time = watchdogZeroEvent.when() - curTick();
128 time = time / parent->clockPeriod() /
129 power(16, watchdogControl.prescalar);
130 DPRINTF(Timer, "-- returning counter at %d\n", time);
131 pkt->set<uint32_t>(time);
132 break;
133 case WatchdogControlReg:
134 pkt->set<uint32_t>(watchdogControl);
135 break;
136 case WatchdogIntStatusReg:
137 pkt->set<uint32_t>(rawIntWatchdog);
138 break;
139 case WatchdogResetStatusReg:
140 pkt->set<uint32_t>(rawResetWatchdog);
141 break;
142 case WatchdogDisableReg:
143 panic("Tried to read from WatchdogDisableRegister\n");
144 break;
145 default:
146 panic("Tried to read CpuLocalTimer at offset %#x\n", daddr);
147 break;
148 }
149}
150
151Tick
152CpuLocalTimer::write(PacketPtr pkt)
153{
154 assert(pkt->getAddr() >= pioAddr && pkt->getAddr() < pioAddr + pioSize);
155 assert(pkt->getSize() == 4);
156 Addr daddr = pkt->getAddr() - pioAddr;
157 pkt->allocate();
158 int cpu_id = pkt->req->contextId();
159 DPRINTF(Timer, "Writing to CpuLocalTimer at offset: %#x\n", daddr);
160 assert(cpu_id >= 0);
161 assert(cpu_id < CPU_MAX);
162
163 if (daddr < Timer::Size)
164 localTimer[cpu_id].write(pkt, daddr);
165 else
166 panic("Tried to write CpuLocalTimer at offset %#x that doesn't exist\n", daddr);
167 pkt->makeAtomicResponse();
168 return pioDelay;
169}
170
171void
172CpuLocalTimer::Timer::write(PacketPtr pkt, Addr daddr)
173{
174 DPRINTF(Timer, "Writing to CpuLocalTimer at offset: %#x\n", daddr);
175 bool old_enable;
176 bool old_wd_mode;
177 uint32_t old_val;
178
179 switch (daddr) {
180 case TimerLoadReg:
181 // Writing to this register also resets the counter register and
182 // starts decrementing if the counter is enabled.
183 timerLoadValue = pkt->get<uint32_t>();
184 restartTimerCounter(timerLoadValue);
185 break;
186 case TimerCounterReg:
187 // Can be written, doesn't start counting unless the timer is enabled
188 restartTimerCounter(pkt->get<uint32_t>());
189 break;
190 case TimerControlReg:
191 old_enable = timerControl.enable;
192 timerControl = pkt->get<uint32_t>();
193 if ((old_enable == 0) && timerControl.enable)
194 restartTimerCounter(timerLoadValue);
195 break;
196 case TimerIntStatusReg:
197 rawIntTimer = false;
198 if (pendingIntTimer) {
199 pendingIntTimer = false;
200 DPRINTF(Timer, "Clearing interrupt\n");
201 }
202 break;
203 case WatchdogLoadReg:
204 watchdogLoadValue = pkt->get<uint32_t>();
205 restartWatchdogCounter(watchdogLoadValue);
206 break;
207 case WatchdogCounterReg:
208 // Can't be written when in watchdog mode, but can in timer mode
209 if (!watchdogControl.watchdogMode) {
210 restartWatchdogCounter(pkt->get<uint32_t>());
211 }
212 break;
213 case WatchdogControlReg:
214 old_enable = watchdogControl.enable;
215 old_wd_mode = watchdogControl.watchdogMode;
216 watchdogControl = pkt->get<uint32_t>();
217 if ((old_enable == 0) && watchdogControl.enable)
218 restartWatchdogCounter(watchdogLoadValue);
219 // cannot disable watchdog using control register
220 if ((old_wd_mode == 1) && watchdogControl.watchdogMode == 0)
221 watchdogControl.watchdogMode = 1;
222 break;
223 case WatchdogIntStatusReg:
224 rawIntWatchdog = false;
225 if (pendingIntWatchdog) {
226 pendingIntWatchdog = false;
227 DPRINTF(Timer, "Clearing watchdog interrupt\n");
228 }
229 break;
230 case WatchdogResetStatusReg:
231 rawResetWatchdog = false;
232 DPRINTF(Timer, "Clearing watchdog reset flag\n");
233 break;
234 case WatchdogDisableReg:
235 old_val = watchdogDisableReg;
236 watchdogDisableReg = pkt->get<uint32_t>();
237 // if this sequence is observed, turn off watchdog mode
238 if (old_val == 0x12345678 && watchdogDisableReg == 0x87654321)
239 watchdogControl.watchdogMode = 0;
240 break;
241 default:
242 panic("Tried to write CpuLocalTimer timer at offset %#x\n", daddr);
243 break;
244 }
245}
246
247//XXX: Two functions are needed because the control registers are different types
248void
249CpuLocalTimer::Timer::restartTimerCounter(uint32_t val)
250{
251 DPRINTF(Timer, "Resetting timer counter with value %#x\n", val);
252 if (!timerControl.enable)
253 return;
254
255 Tick time = parent->clockPeriod() * power(16, timerControl.prescalar);
256 time *= val;
257
258 if (timerZeroEvent.scheduled()) {
259 DPRINTF(Timer, "-- Event was already schedule, de-scheduling\n");
260 parent->deschedule(timerZeroEvent);
261 }
262 parent->schedule(timerZeroEvent, curTick() + time);
263 DPRINTF(Timer, "-- Scheduling new event for: %d\n", curTick() + time);
264}
265
266void
267CpuLocalTimer::Timer::restartWatchdogCounter(uint32_t val)
268{
269 DPRINTF(Timer, "Resetting watchdog counter with value %#x\n", val);
270 if (!watchdogControl.enable)
271 return;
272
273 Tick time = parent->clockPeriod() * power(16, watchdogControl.prescalar);
274 time *= val;
275
276 if (watchdogZeroEvent.scheduled()) {
277 DPRINTF(Timer, "-- Event was already schedule, de-scheduling\n");
278 parent->deschedule(watchdogZeroEvent);
279 }
280 parent->schedule(watchdogZeroEvent, curTick() + time);
281 DPRINTF(Timer, "-- Scheduling new event for: %d\n", curTick() + time);
282}
283//////
284
285void
286CpuLocalTimer::Timer::timerAtZero()
287{
288 if (!timerControl.enable)
289 return;
290
291 DPRINTF(Timer, "Timer Counter reached zero\n");
292
293 rawIntTimer = true;
294 bool old_pending = pendingIntTimer;
295 if (timerControl.intEnable)
296 pendingIntTimer = true;
297 if (pendingIntTimer && !old_pending) {
298 DPRINTF(Timer, "-- Causing interrupt\n");
299 parent->gic->sendPPInt(intNumTimer, cpuNum);
300 }
301
302 if (!timerControl.autoReload)
303 return;
304 else
305 restartTimerCounter(timerLoadValue);
306}
307
308void
309CpuLocalTimer::Timer::watchdogAtZero()
310{
311 if (!watchdogControl.enable)
312 return;
313
314 DPRINTF(Timer, "Watchdog Counter reached zero\n");
315
316 rawIntWatchdog = true;
317 bool old_pending = pendingIntWatchdog;
318 // generates an interrupt only if the watchdog is in timer
319 // mode.
320 if (watchdogControl.intEnable && !watchdogControl.watchdogMode)
321 pendingIntWatchdog = true;
322 else if (watchdogControl.watchdogMode) {
323 rawResetWatchdog = true;
324 fatal("gem5 ARM Model does not support true watchdog operation!\n");
325 //XXX: Should we ever support a true watchdog reset?
326 }
327
328 if (pendingIntWatchdog && !old_pending) {
329 DPRINTF(Timer, "-- Causing interrupt\n");
330 parent->gic->sendPPInt(intNumWatchdog, cpuNum);
331 }
332
333 if (watchdogControl.watchdogMode)
334 return;
335 else if (watchdogControl.autoReload)
336 restartWatchdogCounter(watchdogLoadValue);
337}
338
339void
340CpuLocalTimer::Timer::serialize(std::ostream &os)
341{
342 DPRINTF(Checkpoint, "Serializing Arm CpuLocalTimer\n");
343 SERIALIZE_SCALAR(intNumTimer);
344 SERIALIZE_SCALAR(intNumWatchdog);
345
346 uint32_t timer_control_serial = timerControl;
347 uint32_t watchdog_control_serial = watchdogControl;
348 SERIALIZE_SCALAR(timer_control_serial);
349 SERIALIZE_SCALAR(watchdog_control_serial);
350
351 SERIALIZE_SCALAR(rawIntTimer);
352 SERIALIZE_SCALAR(rawIntWatchdog);
353 SERIALIZE_SCALAR(rawResetWatchdog);
354 SERIALIZE_SCALAR(watchdogDisableReg);
355 SERIALIZE_SCALAR(pendingIntTimer);
356 SERIALIZE_SCALAR(pendingIntWatchdog);
357 SERIALIZE_SCALAR(timerLoadValue);
358 SERIALIZE_SCALAR(watchdogLoadValue);
359
360 bool timer_is_in_event = timerZeroEvent.scheduled();
361 SERIALIZE_SCALAR(timer_is_in_event);
362 bool watchdog_is_in_event = watchdogZeroEvent.scheduled();
363 SERIALIZE_SCALAR(watchdog_is_in_event);
364
365 Tick timer_event_time;
366 if (timer_is_in_event){
367 timer_event_time = timerZeroEvent.when();
368 SERIALIZE_SCALAR(timer_event_time);
369 }
370 Tick watchdog_event_time;
371 if (watchdog_is_in_event){
372 watchdog_event_time = watchdogZeroEvent.when();
373 SERIALIZE_SCALAR(watchdog_event_time);
374 }
375}
376
377void
378CpuLocalTimer::Timer::unserialize(Checkpoint *cp, const std::string &section)
379{
380 DPRINTF(Checkpoint, "Unserializing Arm CpuLocalTimer\n");
381
382 UNSERIALIZE_SCALAR(intNumTimer);
383 UNSERIALIZE_SCALAR(intNumWatchdog);
384
385 uint32_t timer_control_serial;
386 UNSERIALIZE_SCALAR(timer_control_serial);
387 timerControl = timer_control_serial;
388 uint32_t watchdog_control_serial;
389 UNSERIALIZE_SCALAR(watchdog_control_serial);
390 watchdogControl = watchdog_control_serial;
391
392 UNSERIALIZE_SCALAR(rawIntTimer);
393 UNSERIALIZE_SCALAR(rawIntWatchdog);
394 UNSERIALIZE_SCALAR(rawResetWatchdog);
395 UNSERIALIZE_SCALAR(watchdogDisableReg);
396 UNSERIALIZE_SCALAR(pendingIntTimer);
397 UNSERIALIZE_SCALAR(pendingIntWatchdog);
398 UNSERIALIZE_SCALAR(timerLoadValue);
399 UNSERIALIZE_SCALAR(watchdogLoadValue);
400
401 bool timer_is_in_event;
402 UNSERIALIZE_SCALAR(timer_is_in_event);
403 bool watchdog_is_in_event;
404 UNSERIALIZE_SCALAR(watchdog_is_in_event);
405
406 Tick timer_event_time;
407 if (timer_is_in_event){
408 UNSERIALIZE_SCALAR(timer_event_time);
409 parent->schedule(timerZeroEvent, timer_event_time);
410 }
411 Tick watchdog_event_time;
412 if (watchdog_is_in_event) {
413 UNSERIALIZE_SCALAR(watchdog_event_time);
414 parent->schedule(watchdogZeroEvent, watchdog_event_time);
415 }
416}
417
418
419
420void
421CpuLocalTimer::serialize(std::ostream &os)
422{
423 for (int i = 0; i < CPU_MAX; i++) {
424 nameOut(os, csprintf("%s.timer%d", name(), i));
425 localTimer[i].serialize(os);
426 }
427}
428
429void
430CpuLocalTimer::unserialize(Checkpoint *cp, const std::string &section)
431{
432 for (int i = 0; i < CPU_MAX; i++) {
433 localTimer[i].unserialize(cp, csprintf("%s.timer%d", section, i));
434 }
435}
436
437CpuLocalTimer *
438CpuLocalTimerParams::create()
439{
440 return new CpuLocalTimer(this);
441}