src/dev/arm/rtc_pl031.cc - public/gem5 - Git at Google

 /*
  * Copyright (c) 2010-2012 ARM Limited
  * All rights reserved
  *
  * The license below extends only to copyright in the software and shall
  * not be construed as granting a license to any other intellectual
  * property including but not limited to intellectual property relating
  * to a hardware implementation of the functionality of the software
  * licensed hereunder.  You may use the software subject to the license
  * terms below provided that you ensure that this notice is replicated
  * unmodified and in its entirety in all distributions of the software,
  * modified or unmodified, in source code or in binary form.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met: redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer;
  * redistributions in binary form must reproduce the above copyright
  * notice, this list of conditions and the following disclaimer in the
  * documentation and/or other materials provided with the distribution;
  * neither the name of the copyright holders nor the names of its
  * contributors may be used to endorse or promote products derived from
  * this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  *
  * Authors: Ali Saidi
  */

 #include "dev/arm/rtc_pl031.hh"

 #include "base/intmath.hh"
 #include "base/time.hh"
 #include "base/trace.hh"
 #include "debug/Checkpoint.hh"
 #include "debug/Timer.hh"
 #include "dev/arm/amba_device.hh"
 #include "mem/packet.hh"
 #include "mem/packet_access.hh"

 PL031::PL031(Params *p)
     : AmbaIntDevice(p, 0xfff), timeVal(mkutctime(&p->time)),
       lastWrittenTick(0), loadVal(0), matchVal(0),
       rawInt(false), maskInt(false), pendingInt(false),
       matchEvent([this]{ counterMatch(); }, name())
 {
 }


 Tick
 PL031::read(PacketPtr pkt)
 {
     assert(pkt->getAddr() >= pioAddr && pkt->getAddr() < pioAddr + pioSize);
     assert(pkt->getSize() == 4);
     Addr daddr = pkt->getAddr() - pioAddr;
     uint32_t data;

     DPRINTF(Timer, "Reading from RTC at offset: %#x\n", daddr);

     switch (daddr) {
       case DataReg:
         data = timeVal + ((curTick() - lastWrittenTick) / SimClock::Int::s);
         break;
       case MatchReg:
         data = matchVal;
         break;
       case LoadReg:
         data = loadVal;
         break;
       case ControlReg:
         data = 1; // Always enabled otherwise there is no point
         break;
       case IntMask:
         data = maskInt;
         break;
       case RawISR:
         data = rawInt;
         break;
       case MaskedISR:
         data = pendingInt;
         break;
       default:
         if (readId(pkt, ambaId, pioAddr)) {
             // Hack for variable sized access
             data = pkt->get<uint32_t>();
             break;
         }
         panic("Tried to read PL031 at offset %#x that doesn't exist\n", daddr);
         break;
     }

     switch(pkt->getSize()) {
       case 1:
         pkt->set<uint8_t>(data);
         break;
       case 2:
         pkt->set<uint16_t>(data);
         break;
       case 4:
         pkt->set<uint32_t>(data);
         break;
       default:
         panic("Uart read size too big?\n");
         break;
     }


     pkt->makeAtomicResponse();
     return pioDelay;
 }

 Tick
 PL031::write(PacketPtr pkt)
 {
     assert(pkt->getAddr() >= pioAddr && pkt->getAddr() < pioAddr + pioSize);
     assert(pkt->getSize() == 4);
     Addr daddr = pkt->getAddr() - pioAddr;
     DPRINTF(Timer, "Writing to RTC at offset: %#x\n", daddr);

     switch (daddr) {
       case DataReg:
         break;
       case MatchReg:
         matchVal = pkt->get<uint32_t>();
         resyncMatch();
         break;
       case LoadReg:
         lastWrittenTick = curTick();
         timeVal = pkt->get<uint32_t>();
         loadVal = timeVal;
         resyncMatch();
         break;
       case ControlReg:
         break; // Can't stop when started
       case IntMask:
         maskInt = pkt->get<uint32_t>();
         break;
       case IntClear:
         if (pkt->get<uint32_t>()) {
             rawInt = false;
             pendingInt = false;
         }
         break;
       default:
         if (readId(pkt, ambaId, pioAddr))
             break;
         panic("Tried to read PL031 at offset %#x that doesn't exist\n", daddr);
         break;
     }

     pkt->makeAtomicResponse();
     return pioDelay;
 }

 void
 PL031::resyncMatch()
 {
     DPRINTF(Timer, "Setting up new match event match=%d time=%d\n", matchVal,
             timeVal);

     uint32_t seconds_until = matchVal - timeVal;
     Tick ticks_until = SimClock::Int::s * seconds_until;

     if (matchEvent.scheduled()) {
         DPRINTF(Timer, "-- Event was already schedule, de-scheduling\n");
         deschedule(matchEvent);
     }
     schedule(matchEvent, curTick() + ticks_until);
     DPRINTF(Timer, "-- Scheduling new event for: %d\n", curTick() + ticks_until);
 }

 void
 PL031::counterMatch()
 {
     DPRINTF(Timer, "Counter reached zero\n");

     rawInt = true;
     bool old_pending = pendingInt;
     pendingInt = maskInt & rawInt;
     if (pendingInt && !old_pending) {
         DPRINTF(Timer, "-- Causing interrupt\n");
         gic->sendInt(intNum);
     }
 }

 void
 PL031::serialize(CheckpointOut &cp) const
 {
     DPRINTF(Checkpoint, "Serializing Arm PL031\n");
     SERIALIZE_SCALAR(timeVal);
     SERIALIZE_SCALAR(lastWrittenTick);
     SERIALIZE_SCALAR(loadVal);
     SERIALIZE_SCALAR(matchVal);
     SERIALIZE_SCALAR(rawInt);
     SERIALIZE_SCALAR(maskInt);
     SERIALIZE_SCALAR(pendingInt);

     bool is_in_event = matchEvent.scheduled();
     SERIALIZE_SCALAR(is_in_event);

     Tick event_time;
     if (is_in_event){
         event_time = matchEvent.when();
         SERIALIZE_SCALAR(event_time);
     }
 }

 void
 PL031::unserialize(CheckpointIn &cp)
 {
     DPRINTF(Checkpoint, "Unserializing Arm PL031\n");

     UNSERIALIZE_SCALAR(timeVal);
     UNSERIALIZE_SCALAR(lastWrittenTick);
     UNSERIALIZE_SCALAR(loadVal);
     UNSERIALIZE_SCALAR(matchVal);
     UNSERIALIZE_SCALAR(rawInt);
     UNSERIALIZE_SCALAR(maskInt);
     UNSERIALIZE_SCALAR(pendingInt);

     bool is_in_event;
     UNSERIALIZE_SCALAR(is_in_event);

     Tick event_time;
     if (is_in_event){
         UNSERIALIZE_SCALAR(event_time);
         schedule(matchEvent, event_time);
     }
 }


 PL031 *
 PL031Params::create()
 {
     return new PL031(this);
 }
	/*
	* Copyright (c) 2010-2012 ARM Limited
	* All rights reserved
	*
	* The license below extends only to copyright in the software and shall
	* not be construed as granting a license to any other intellectual
	* property including but not limited to intellectual property relating
	* to a hardware implementation of the functionality of the software
	* licensed hereunder. You may use the software subject to the license
	* terms below provided that you ensure that this notice is replicated
	* unmodified and in its entirety in all distributions of the software,
	* modified or unmodified, in source code or in binary form.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions are
	* met: redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer;
	* redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution;
	* neither the name of the copyright holders nor the names of its
	* contributors may be used to endorse or promote products derived from
	* this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*
	* Authors: Ali Saidi
	*/

	#include "dev/arm/rtc_pl031.hh"

	#include "base/intmath.hh"
	#include "base/time.hh"
	#include "base/trace.hh"
	#include "debug/Checkpoint.hh"
	#include "debug/Timer.hh"
	#include "dev/arm/amba_device.hh"
	#include "mem/packet.hh"
	#include "mem/packet_access.hh"

	PL031::PL031(Params *p)
	: AmbaIntDevice(p, 0xfff), timeVal(mkutctime(&p->time)),
	lastWrittenTick(0), loadVal(0), matchVal(0),
	rawInt(false), maskInt(false), pendingInt(false),
	matchEvent([this]{ counterMatch(); }, name())
	{
	}


	Tick
	PL031::read(PacketPtr pkt)
	{
	assert(pkt->getAddr() >= pioAddr && pkt->getAddr() < pioAddr + pioSize);
	assert(pkt->getSize() == 4);
	Addr daddr = pkt->getAddr() - pioAddr;
	uint32_t data;

	DPRINTF(Timer, "Reading from RTC at offset: %#x\n", daddr);

	switch (daddr) {
	case DataReg:
	data = timeVal + ((curTick() - lastWrittenTick) / SimClock::Int::s);
	break;
	case MatchReg:
	data = matchVal;
	break;
	case LoadReg:
	data = loadVal;
	break;
	case ControlReg:
	data = 1; // Always enabled otherwise there is no point
	break;
	case IntMask:
	data = maskInt;
	break;
	case RawISR:
	data = rawInt;
	break;
	case MaskedISR:
	data = pendingInt;
	break;
	default:
	if (readId(pkt, ambaId, pioAddr)) {
	// Hack for variable sized access
	data = pkt->get<uint32_t>();
	break;
	}
	panic("Tried to read PL031 at offset %#x that doesn't exist\n", daddr);
	break;
	}

	switch(pkt->getSize()) {
	case 1:
	pkt->set<uint8_t>(data);
	break;
	case 2:
	pkt->set<uint16_t>(data);
	break;
	case 4:
	pkt->set<uint32_t>(data);
	break;
	default:
	panic("Uart read size too big?\n");
	break;
	}


	pkt->makeAtomicResponse();
	return pioDelay;
	}

	Tick
	PL031::write(PacketPtr pkt)
	{
	assert(pkt->getAddr() >= pioAddr && pkt->getAddr() < pioAddr + pioSize);
	assert(pkt->getSize() == 4);
	Addr daddr = pkt->getAddr() - pioAddr;
	DPRINTF(Timer, "Writing to RTC at offset: %#x\n", daddr);

	switch (daddr) {
	case DataReg:
	break;
	case MatchReg:
	matchVal = pkt->get<uint32_t>();
	resyncMatch();
	break;
	case LoadReg:
	lastWrittenTick = curTick();
	timeVal = pkt->get<uint32_t>();
	loadVal = timeVal;
	resyncMatch();
	break;
	case ControlReg:
	break; // Can't stop when started
	case IntMask:
	maskInt = pkt->get<uint32_t>();
	break;
	case IntClear:
	if (pkt->get<uint32_t>()) {
	rawInt = false;
	pendingInt = false;
	}
	break;
	default:
	if (readId(pkt, ambaId, pioAddr))
	break;
	panic("Tried to read PL031 at offset %#x that doesn't exist\n", daddr);
	break;
	}

	pkt->makeAtomicResponse();
	return pioDelay;
	}

	void
	PL031::resyncMatch()
	{
	DPRINTF(Timer, "Setting up new match event match=%d time=%d\n", matchVal,
	timeVal);

	uint32_t seconds_until = matchVal - timeVal;
	Tick ticks_until = SimClock::Int::s * seconds_until;

	if (matchEvent.scheduled()) {
	DPRINTF(Timer, "-- Event was already schedule, de-scheduling\n");
	deschedule(matchEvent);
	}
	schedule(matchEvent, curTick() + ticks_until);
	DPRINTF(Timer, "-- Scheduling new event for: %d\n", curTick() + ticks_until);
	}

	void
	PL031::counterMatch()
	{
	DPRINTF(Timer, "Counter reached zero\n");

	rawInt = true;
	bool old_pending = pendingInt;
	pendingInt = maskInt & rawInt;
	if (pendingInt && !old_pending) {
	DPRINTF(Timer, "-- Causing interrupt\n");
	gic->sendInt(intNum);
	}
	}

	void
	PL031::serialize(CheckpointOut &cp) const
	{
	DPRINTF(Checkpoint, "Serializing Arm PL031\n");
	SERIALIZE_SCALAR(timeVal);
	SERIALIZE_SCALAR(lastWrittenTick);
	SERIALIZE_SCALAR(loadVal);
	SERIALIZE_SCALAR(matchVal);
	SERIALIZE_SCALAR(rawInt);
	SERIALIZE_SCALAR(maskInt);
	SERIALIZE_SCALAR(pendingInt);

	bool is_in_event = matchEvent.scheduled();
	SERIALIZE_SCALAR(is_in_event);

	Tick event_time;
	if (is_in_event){
	event_time = matchEvent.when();
	SERIALIZE_SCALAR(event_time);
	}
	}

	void
	PL031::unserialize(CheckpointIn &cp)
	{
	DPRINTF(Checkpoint, "Unserializing Arm PL031\n");

	UNSERIALIZE_SCALAR(timeVal);
	UNSERIALIZE_SCALAR(lastWrittenTick);
	UNSERIALIZE_SCALAR(loadVal);
	UNSERIALIZE_SCALAR(matchVal);
	UNSERIALIZE_SCALAR(rawInt);
	UNSERIALIZE_SCALAR(maskInt);
	UNSERIALIZE_SCALAR(pendingInt);

	bool is_in_event;
	UNSERIALIZE_SCALAR(is_in_event);

	Tick event_time;
	if (is_in_event){
	UNSERIALIZE_SCALAR(event_time);
	schedule(matchEvent, event_time);
	}
	}



	PL031 *
	PL031Params::create()
	{
	return new PL031(this);
	}