1/*
2 * Copyright (c) 2010-2011 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), 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].clock = clock;
62 localTimer[i].cpuNum = i;
63 }
64 pioSize = 0x38;
65}
66
67CpuLocalTimer::Timer::Timer()
68 : timerControl(0x0), watchdogControl(0x0), rawIntTimer(false), rawIntWatchdog(false),
69 rawResetWatchdog(false), watchdogDisableReg(0x0), pendingIntTimer(false), pendingIntWatchdog(false),
70 timerLoadValue(0x0), watchdogLoadValue(0x0), timerZeroEvent(this), watchdogZeroEvent(this)
71{
72}
73
74Tick
75CpuLocalTimer::read(PacketPtr pkt)
76{
77 assert(pkt->getAddr() >= pioAddr && pkt->getAddr() < pioAddr + pioSize);
78 assert(pkt->getSize() == 4);
79 Addr daddr = pkt->getAddr() - pioAddr;
80 pkt->allocate();
81 int cpu_id = pkt->req->contextId();
82 DPRINTF(Timer, "Reading from CpuLocalTimer at offset: %#x\n", daddr);
83 assert(cpu_id >= 0);
84 assert(cpu_id < CPU_MAX);
85
86 if (daddr < Timer::Size)
87 localTimer[cpu_id].read(pkt, daddr);
88 else
89 panic("Tried to read CpuLocalTimer at offset %#x that doesn't exist\n", daddr);
90 pkt->makeAtomicResponse();
91 return pioDelay;
92}
93
94
95void
96CpuLocalTimer::Timer::read(PacketPtr pkt, Addr daddr)
97{
98 DPRINTF(Timer, "Reading from CpuLocalTimer at offset: %#x\n", daddr);
99 Tick time;
100
101 switch(daddr) {
102 case TimerLoadReg:
103 pkt->set<uint32_t>(timerLoadValue);
104 break;
105 case TimerCounterReg:
106 DPRINTF(Timer, "Event schedule for timer %d, clock=%d, prescale=%d\n",
107 timerZeroEvent.when(), clock, timerControl.prescalar);
108 time = timerZeroEvent.when() - curTick();
109 time = time / clock / 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, "Event schedule for watchdog %d, clock=%d, prescale=%d\n",
124 watchdogZeroEvent.when(), clock, watchdogControl.prescalar);
125 time = watchdogZeroEvent.when() - curTick();
126 time = time / clock / power(16, watchdogControl.prescalar);
127 DPRINTF(Timer, "-- returning counter at %d\n", time);
128 pkt->set<uint32_t>(time);
129 break;
130 case WatchdogControlReg:
131 pkt->set<uint32_t>(watchdogControl);
132 break;
133 case WatchdogIntStatusReg:
134 pkt->set<uint32_t>(rawIntWatchdog);
135 break;
136 case WatchdogResetStatusReg:
137 pkt->set<uint32_t>(rawResetWatchdog);
138 break;
139 case WatchdogDisableReg:
140 panic("Tried to read from WatchdogDisableRegister\n");
141 break;
142 default:
143 panic("Tried to read CpuLocalTimer at offset %#x\n", daddr);
144 break;
145 }
146}
147
148Tick
149CpuLocalTimer::write(PacketPtr pkt)
150{
151 assert(pkt->getAddr() >= pioAddr && pkt->getAddr() < pioAddr + pioSize);
152 assert(pkt->getSize() == 4);
153 Addr daddr = pkt->getAddr() - pioAddr;
154 pkt->allocate();
155 int cpu_id = pkt->req->contextId();
156 DPRINTF(Timer, "Writing to CpuLocalTimer at offset: %#x\n", daddr);
157 assert(cpu_id >= 0);
158 assert(cpu_id < CPU_MAX);
159
160 if (daddr < Timer::Size)
161 localTimer[cpu_id].write(pkt, daddr);
162 else
163 panic("Tried to write CpuLocalTimer at offset %#x that doesn't exist\n", daddr);
164 pkt->makeAtomicResponse();
165 return pioDelay;
166}
167
168void
169CpuLocalTimer::Timer::write(PacketPtr pkt, Addr daddr)
170{
171 DPRINTF(Timer, "Writing to CpuLocalTimer at offset: %#x\n", daddr);
172 bool old_enable;
173 bool old_wd_mode;
174 uint32_t old_val;
175
176 switch (daddr) {
177 case TimerLoadReg:
178 // Writing to this register also resets the counter register and
179 // starts decrementing if the counter is enabled.
180 timerLoadValue = pkt->get<uint32_t>();
181 restartTimerCounter(timerLoadValue);
182 break;
183 case TimerCounterReg:
184 // Can be written, doesn't start counting unless the timer is enabled
185 restartTimerCounter(pkt->get<uint32_t>());
186 break;
187 case TimerControlReg:
188 old_enable = timerControl.enable;
189 timerControl = pkt->get<uint32_t>();
190 if ((old_enable == 0) && timerControl.enable)
191 restartTimerCounter(timerLoadValue);
192 break;
193 case TimerIntStatusReg:
194 rawIntTimer = false;
195 if (pendingIntTimer) {
196 pendingIntTimer = false;
197 DPRINTF(Timer, "Clearing interrupt\n");
198 }
199 break;
200 case WatchdogLoadReg:
201 watchdogLoadValue = pkt->get<uint32_t>();
202 restartWatchdogCounter(watchdogLoadValue);
203 break;
204 case WatchdogCounterReg:
205 // Can't be written when in watchdog mode, but can in timer mode
206 if (!watchdogControl.watchdogMode) {
207 restartWatchdogCounter(pkt->get<uint32_t>());
208 }
209 break;
210 case WatchdogControlReg:
211 old_enable = watchdogControl.enable;
212 old_wd_mode = watchdogControl.watchdogMode;
213 watchdogControl = pkt->get<uint32_t>();
214 if ((old_enable == 0) && watchdogControl.enable)
215 restartWatchdogCounter(watchdogLoadValue);
216 // cannot disable watchdog using control register
217 if ((old_wd_mode == 1) && watchdogControl.watchdogMode == 0)
218 watchdogControl.watchdogMode = 1;
219 break;
220 case WatchdogIntStatusReg:
221 rawIntWatchdog = false;
222 if (pendingIntWatchdog) {
223 pendingIntWatchdog = false;
224 DPRINTF(Timer, "Clearing watchdog interrupt\n");
225 }
226 break;
227 case WatchdogResetStatusReg:
228 rawResetWatchdog = false;
229 DPRINTF(Timer, "Clearing watchdog reset flag\n");
230 break;
231 case WatchdogDisableReg:
232 old_val = watchdogDisableReg;
233 watchdogDisableReg = pkt->get<uint32_t>();
234 // if this sequence is observed, turn off watchdog mode
235 if (old_val == 0x12345678 && watchdogDisableReg == 0x87654321)
236 watchdogControl.watchdogMode = 0;
237 break;
238 default:
239 panic("Tried to write CpuLocalTimer timer at offset %#x\n", daddr);
240 break;
241 }
242}
243
244//XXX: Two functions are needed because the control registers are different types
245void
246CpuLocalTimer::Timer::restartTimerCounter(uint32_t val)
247{
248 DPRINTF(Timer, "Resetting timer counter with value %#x\n", val);
249 if (!timerControl.enable)
250 return;
251
252 Tick time = clock * power(16, timerControl.prescalar);
253 time *= val;
254
255 if (timerZeroEvent.scheduled()) {
256 DPRINTF(Timer, "-- Event was already schedule, de-scheduling\n");
257 parent->deschedule(timerZeroEvent);
258 }
259 parent->schedule(timerZeroEvent, curTick() + time);
260 DPRINTF(Timer, "-- Scheduling new event for: %d\n", curTick() + time);
261}
262
263void
264CpuLocalTimer::Timer::restartWatchdogCounter(uint32_t val)
265{
266 DPRINTF(Timer, "Resetting watchdog counter with value %#x\n", val);
267 if (!watchdogControl.enable)
268 return;
269
270 Tick time = clock * power(16, watchdogControl.prescalar);
271 time *= val;
272
273 if (watchdogZeroEvent.scheduled()) {
274 DPRINTF(Timer, "-- Event was already schedule, de-scheduling\n");
275 parent->deschedule(watchdogZeroEvent);
276 }
277 parent->schedule(watchdogZeroEvent, curTick() + time);
278 DPRINTF(Timer, "-- Scheduling new event for: %d\n", curTick() + time);
279}
280//////
281
282void
283CpuLocalTimer::Timer::timerAtZero()
284{
285 if (!timerControl.enable)
286 return;
287
288 DPRINTF(Timer, "Timer Counter reached zero\n");
289
290 rawIntTimer = true;
291 bool old_pending = pendingIntTimer;
292 if (timerControl.intEnable)
293 pendingIntTimer = true;
294 if (pendingIntTimer && !old_pending) {
295 DPRINTF(Timer, "-- Causing interrupt\n");
296 parent->gic->sendPPInt(intNumTimer, cpuNum);
297 }
298
299 if (!timerControl.autoReload)
300 return;
301 else
302 restartTimerCounter(timerLoadValue);
303}
304
305void
306CpuLocalTimer::Timer::watchdogAtZero()
307{
308 if (!watchdogControl.enable)
309 return;
310
311 DPRINTF(Timer, "Watchdog Counter reached zero\n");
312
313 rawIntWatchdog = true;
314 bool old_pending = pendingIntWatchdog;
315 // generates an interrupt only if the watchdog is in timer
316 // mode.
317 if (watchdogControl.intEnable && !watchdogControl.watchdogMode)
318 pendingIntWatchdog = true;
319 else if (watchdogControl.watchdogMode) {
320 rawResetWatchdog = true;
321 fatal("gem5 ARM Model does not support true watchdog operation!\n");
322 //XXX: Should we ever support a true watchdog reset?
323 }
324
325 if (pendingIntWatchdog && !old_pending) {
326 DPRINTF(Timer, "-- Causing interrupt\n");
327 parent->gic->sendPPInt(intNumWatchdog, cpuNum);
328 }
329
330 if (watchdogControl.watchdogMode)
331 return;
332 else if (watchdogControl.autoReload)
333 restartWatchdogCounter(watchdogLoadValue);
334}
335
336void
337CpuLocalTimer::Timer::serialize(std::ostream &os)
338{
339 DPRINTF(Checkpoint, "Serializing Arm CpuLocalTimer\n");
340 SERIALIZE_SCALAR(intNumTimer);
341 SERIALIZE_SCALAR(intNumWatchdog);
342
343 uint32_t timer_control_serial = timerControl;
344 uint32_t watchdog_control_serial = watchdogControl;
345 SERIALIZE_SCALAR(timer_control_serial);
346 SERIALIZE_SCALAR(watchdog_control_serial);
347
348 SERIALIZE_SCALAR(rawIntTimer);
349 SERIALIZE_SCALAR(rawIntWatchdog);
350 SERIALIZE_SCALAR(rawResetWatchdog);
351 SERIALIZE_SCALAR(watchdogDisableReg);
352 SERIALIZE_SCALAR(pendingIntTimer);
353 SERIALIZE_SCALAR(pendingIntWatchdog);
354 SERIALIZE_SCALAR(timerLoadValue);
355 SERIALIZE_SCALAR(watchdogLoadValue);
356
357 bool timer_is_in_event = timerZeroEvent.scheduled();
358 SERIALIZE_SCALAR(timer_is_in_event);
359 bool watchdog_is_in_event = watchdogZeroEvent.scheduled();
360 SERIALIZE_SCALAR(watchdog_is_in_event);
361
362 Tick timer_event_time;
363 if (timer_is_in_event){
364 timer_event_time = timerZeroEvent.when();
365 SERIALIZE_SCALAR(timer_event_time);
366 }
367 Tick watchdog_event_time;
368 if (watchdog_is_in_event){
369 watchdog_event_time = watchdogZeroEvent.when();
370 SERIALIZE_SCALAR(watchdog_event_time);
371 }
372}
373
374void
375CpuLocalTimer::Timer::unserialize(Checkpoint *cp, const std::string &section)
376{
377 DPRINTF(Checkpoint, "Unserializing Arm CpuLocalTimer\n");
378
379 UNSERIALIZE_SCALAR(intNumTimer);
380 UNSERIALIZE_SCALAR(intNumWatchdog);
381
382 uint32_t timer_control_serial;
383 UNSERIALIZE_SCALAR(timer_control_serial);
384 timerControl = timer_control_serial;
385 uint32_t watchdog_control_serial;
386 UNSERIALIZE_SCALAR(watchdog_control_serial);
387 watchdogControl = watchdog_control_serial;
388
389 UNSERIALIZE_SCALAR(rawIntTimer);
390 UNSERIALIZE_SCALAR(rawIntWatchdog);
391 UNSERIALIZE_SCALAR(rawResetWatchdog);
392 UNSERIALIZE_SCALAR(watchdogDisableReg);
393 UNSERIALIZE_SCALAR(pendingIntTimer);
394 UNSERIALIZE_SCALAR(pendingIntWatchdog);
395 UNSERIALIZE_SCALAR(timerLoadValue);
396 UNSERIALIZE_SCALAR(watchdogLoadValue);
397
398 bool timer_is_in_event;
399 UNSERIALIZE_SCALAR(timer_is_in_event);
400 bool watchdog_is_in_event;
401 UNSERIALIZE_SCALAR(watchdog_is_in_event);
402
403 Tick timer_event_time;
404 if (timer_is_in_event){
405 UNSERIALIZE_SCALAR(timer_event_time);
406 parent->schedule(timerZeroEvent, timer_event_time);
407 }
408 Tick watchdog_event_time;
409 if (watchdog_is_in_event) {
410 UNSERIALIZE_SCALAR(watchdog_event_time);
411 parent->schedule(watchdogZeroEvent, watchdog_event_time);
412 }
413}
414
415
416
417void
418CpuLocalTimer::serialize(std::ostream &os)
419{
420 for (int i = 0; i < CPU_MAX; i++) {
421 nameOut(os, csprintf("%s.timer%d", name(), i));
422 localTimer[i].serialize(os);
423 }
424}
425
426void
427CpuLocalTimer::unserialize(Checkpoint *cp, const std::string &section)
428{
429 for (int i = 0; i < CPU_MAX; i++) {
430 localTimer[i].unserialize(cp, csprintf("%s.timer%d", section, i));
431 }
432}
433
434CpuLocalTimer *
435CpuLocalTimerParams::create()
436{
437 return new CpuLocalTimer(this);
438}