timer_sp804.cc revision 10905 
1/*
2 * Copyright (c) 2010 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 */
39
40#include "base/intmath.hh"
41#include "base/trace.hh"
42#include "debug/Checkpoint.hh"
43#include "debug/Timer.hh"
44#include "dev/arm/base_gic.hh"
45#include "dev/arm/timer_sp804.hh"
46#include "mem/packet.hh"
47#include "mem/packet_access.hh"
48
49Sp804::Sp804(Params *p)
50    : AmbaPioDevice(p, 0xfff), gic(p->gic),
51      timer0(name() + ".timer0", this, p->int_num0, p->clock0),
52      timer1(name() + ".timer1", this, p->int_num1, p->clock1)
53{
54}
55
56Sp804::Timer::Timer(std::string __name, Sp804 *_parent, int int_num, Tick _clock)
57    : _name(__name), parent(_parent), intNum(int_num), clock(_clock), control(0x20),
58      rawInt(false), pendingInt(false), loadValue(0xffffffff), zeroEvent(this)
59{
60}
61
62
63Tick
64Sp804::read(PacketPtr pkt)
65{
66    assert(pkt->getAddr() >= pioAddr && pkt->getAddr() < pioAddr + pioSize);
67    assert(pkt->getSize() == 4);
68    Addr daddr = pkt->getAddr() - pioAddr;
69    DPRINTF(Timer, "Reading from DualTimer at offset: %#x\n", daddr);
70
71    if (daddr < Timer::Size)
72        timer0.read(pkt, daddr);
73    else if ((daddr - Timer::Size) < Timer::Size)
74        timer1.read(pkt, daddr - Timer::Size);
75    else if (!readId(pkt, ambaId, pioAddr))
76        panic("Tried to read SP804 at offset %#x that doesn't exist\n", daddr);
77    pkt->makeAtomicResponse();
78    return pioDelay;
79}
80
81
82void
83Sp804::Timer::read(PacketPtr pkt, Addr daddr)
84{
85    switch(daddr) {
86      case LoadReg:
87        pkt->set<uint32_t>(loadValue);
88        break;
89      case CurrentReg:
90        DPRINTF(Timer, "Event schedule for %d, clock=%d, prescale=%d\n",
91                zeroEvent.when(), clock, control.timerPrescale);
92        Tick time;
93        time = zeroEvent.when() - curTick();
94        time = time / clock / power(16, control.timerPrescale);
95        DPRINTF(Timer, "-- returning counter at %d\n", time);
96        pkt->set<uint32_t>(time);
97        break;
98      case ControlReg:
99        pkt->set<uint32_t>(control);
100        break;
101      case RawISR:
102        pkt->set<uint32_t>(rawInt);
103        break;
104      case MaskedISR:
105        pkt->set<uint32_t>(pendingInt);
106        break;
107      case BGLoad:
108        pkt->set<uint32_t>(loadValue);
109        break;
110      default:
111        panic("Tried to read SP804 timer at offset %#x\n", daddr);
112        break;
113    }
114    DPRINTF(Timer, "Reading %#x from Timer at offset: %#x\n", pkt->get<uint32_t>(), daddr);
115}
116
117Tick
118Sp804::write(PacketPtr pkt)
119{
120    assert(pkt->getAddr() >= pioAddr && pkt->getAddr() < pioAddr + pioSize);
121    assert(pkt->getSize() == 4);
122    Addr daddr = pkt->getAddr() - pioAddr;
123    DPRINTF(Timer, "Writing to DualTimer at offset: %#x\n", daddr);
124
125    if (daddr < Timer::Size)
126        timer0.write(pkt, daddr);
127    else if ((daddr - Timer::Size) < Timer::Size)
128        timer1.write(pkt, daddr - Timer::Size);
129    else if (!readId(pkt, ambaId, pioAddr))
130        panic("Tried to write SP804 at offset %#x that doesn't exist\n", daddr);
131    pkt->makeAtomicResponse();
132    return pioDelay;
133}
134
135void
136Sp804::Timer::write(PacketPtr pkt, Addr daddr)
137{
138    DPRINTF(Timer, "Writing %#x to Timer at offset: %#x\n", pkt->get<uint32_t>(), daddr);
139    switch (daddr) {
140      case LoadReg:
141        loadValue = pkt->get<uint32_t>();
142        restartCounter(loadValue);
143        break;
144      case CurrentReg:
145        // Spec says this value can't be written, but linux writes it anyway
146        break;
147      case ControlReg:
148        bool old_enable;
149        old_enable = control.timerEnable;
150        control = pkt->get<uint32_t>();
151        if ((old_enable == 0) && control.timerEnable)
152            restartCounter(loadValue);
153        break;
154      case IntClear:
155        rawInt = false;
156        if (pendingInt) {
157            pendingInt = false;
158            DPRINTF(Timer, "Clearing interrupt\n");
159            parent->gic->clearInt(intNum);
160        }
161        break;
162      case BGLoad:
163        loadValue = pkt->get<uint32_t>();
164        break;
165      default:
166        panic("Tried to write SP804 timer at offset %#x\n", daddr);
167        break;
168    }
169}
170
171void
172Sp804::Timer::restartCounter(uint32_t val)
173{
174    DPRINTF(Timer, "Resetting counter with value %#x\n", val);
175    if (!control.timerEnable)
176        return;
177
178    Tick time = clock * power(16, control.timerPrescale);
179    if (control.timerSize)
180        time *= val;
181    else
182        time *= bits(val,15,0);
183
184    if (zeroEvent.scheduled()) {
185        DPRINTF(Timer, "-- Event was already schedule, de-scheduling\n");
186        parent->deschedule(zeroEvent);
187    }
188    parent->schedule(zeroEvent, curTick() + time);
189    DPRINTF(Timer, "-- Scheduling new event for: %d\n", curTick() + time);
190}
191
192void
193Sp804::Timer::counterAtZero()
194{
195    if (!control.timerEnable)
196        return;
197
198    DPRINTF(Timer, "Counter reached zero\n");
199
200    rawInt = true;
201    bool old_pending = pendingInt;
202    if (control.intEnable)
203        pendingInt = true;
204    if (pendingInt && !old_pending) {
205        DPRINTF(Timer, "-- Causing interrupt\n");
206        parent->gic->sendInt(intNum);
207    }
208
209    if (control.oneShot)
210        return;
211
212    // Free-running
213    if (control.timerMode == 0)
214        restartCounter(0xffffffff);
215    else
216        restartCounter(loadValue);
217}
218
219void
220Sp804::Timer::serialize(CheckpointOut &cp) const
221{
222    DPRINTF(Checkpoint, "Serializing Arm Sp804\n");
223
224    uint32_t control_serial = control;
225    SERIALIZE_SCALAR(control_serial);
226
227    SERIALIZE_SCALAR(rawInt);
228    SERIALIZE_SCALAR(pendingInt);
229    SERIALIZE_SCALAR(loadValue);
230
231    bool is_in_event = zeroEvent.scheduled();
232    SERIALIZE_SCALAR(is_in_event);
233
234    Tick event_time;
235    if (is_in_event){
236        event_time = zeroEvent.when();
237        SERIALIZE_SCALAR(event_time);
238    }
239}
240
241void
242Sp804::Timer::unserialize(CheckpointIn &cp)
243{
244    DPRINTF(Checkpoint, "Unserializing Arm Sp804\n");
245
246    uint32_t control_serial;
247    UNSERIALIZE_SCALAR(control_serial);
248    control = control_serial;
249
250    UNSERIALIZE_SCALAR(rawInt);
251    UNSERIALIZE_SCALAR(pendingInt);
252    UNSERIALIZE_SCALAR(loadValue);
253
254    bool is_in_event;
255    UNSERIALIZE_SCALAR(is_in_event);
256
257    Tick event_time;
258    if (is_in_event){
259        UNSERIALIZE_SCALAR(event_time);
260        parent->schedule(zeroEvent, event_time);
261    }
262}
263
264
265
266void
267Sp804::serialize(CheckpointOut &cp) const
268{
269    timer0.serializeSection(cp, "timer0");
270    timer1.serializeSection(cp, "timer1");
271}
272
273void
274Sp804::unserialize(CheckpointIn &cp)
275{
276    timer0.unserializeSection(cp, "timer0");
277    timer1.unserializeSection(cp, "timer1");
278}
279
280Sp804 *
281Sp804Params::create()
282{
283    return new Sp804(this);
284}
285