src/dev/mc146818.cc - arm/gem5 - Git at Google

 /*
  * Copyright (c) 2004-2005 The Regents of The University of Michigan
  * All rights reserved.
  *
  * 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
  *          Andrew Schultz
  *          Miguel Serrano
  */

 #include <sys/time.h>

 #include <ctime>
 #include <string>

 #include "base/bitfield.hh"
 #include "base/time.hh"
 #include "base/trace.hh"
 #include "debug/MC146818.hh"
 #include "dev/mc146818.hh"
 #include "dev/rtcreg.h"

 using namespace std;

 static uint8_t
 bcdize(uint8_t val)
 {
     uint8_t result;
     result = val % 10;
     result += (val / 10) << 4;
     return result;
 }

 static uint8_t
 unbcdize(uint8_t val)
 {
     uint8_t result;
     result = val & 0xf;
     result += (val >> 4) * 10;
     return result;
 }

 void
 MC146818::setTime(const struct tm time)
 {
     curTime = time;
     year = time.tm_year;
     // Unix is 0-11 for month, data seet says start at 1
     mon = time.tm_mon + 1;
     mday = time.tm_mday;
     hour = time.tm_hour;
     min = time.tm_min;
     sec = time.tm_sec;

     // Datasheet says 1 is sunday
     wday = time.tm_wday + 1;

     if (!(stat_regB & RTCB_BIN)) {
         // The datasheet says that the year field can be either BCD or
         // years since 1900.  Linux seems to be happy with years since
         // 1900.
         year = bcdize(year % 100);
         mon = bcdize(mon);
         mday = bcdize(mday);
         hour = bcdize(hour);
         min = bcdize(min);
         sec = bcdize(sec);
     }
 }

 MC146818::MC146818(EventManager *em, const string &n, const struct tm time,
                    bool bcd, Tick frequency)
     : EventManager(em), _name(n), event(this, frequency), tickEvent(this)
 {
     memset(clock_data, 0, sizeof(clock_data));
     stat_regA = RTCA_32768HZ | RTCA_1024HZ;
     stat_regB = RTCB_PRDC_IE | RTCB_24HR;
     if (!bcd)
         stat_regB |= RTCB_BIN;

     setTime(time);
     DPRINTFN("Real-time clock set to %s", asctime(&time));
 }

 MC146818::~MC146818()
 {
     deschedule(tickEvent);
     deschedule(event);
 }

 void
 MC146818::writeData(const uint8_t addr, const uint8_t data)
 {
     if (addr < RTC_STAT_REGA) {
         clock_data[addr] = data;
         curTime.tm_sec = unbcdize(sec);
         curTime.tm_min = unbcdize(min);
         curTime.tm_hour = unbcdize(hour);
         curTime.tm_mday = unbcdize(mday);
         curTime.tm_mon = unbcdize(mon) - 1;
         curTime.tm_year = ((unbcdize(year) + 50) % 100) + 1950;
         curTime.tm_wday = unbcdize(wday) - 1;
     } else {
         switch (addr) {
           case RTC_STAT_REGA:
             // The "update in progress" bit is read only.
             if ((data & ~RTCA_UIP) != (RTCA_32768HZ | RTCA_1024HZ))
                 panic("Unimplemented RTC register A value write!\n");
             replaceBits(stat_regA, data, 6, 0);
             break;
           case RTC_STAT_REGB:
             if ((data & ~(RTCB_PRDC_IE | RTCB_SQWE)) != RTCB_24HR)
                 panic("Write to RTC reg B bits that are not implemented!\n");

             if (data & RTCB_PRDC_IE) {
                 if (!event.scheduled())
                     event.scheduleIntr();
             } else {
                 if (event.scheduled())
                     deschedule(event);
             }
             stat_regB = data;
             break;
           case RTC_STAT_REGC:
           case RTC_STAT_REGD:
             panic("RTC status registers C and D are not implemented.\n");
             break;
         }
     }
 }

 uint8_t
 MC146818::readData(uint8_t addr)
 {
     if (addr < RTC_STAT_REGA)
         return clock_data[addr];
     else {
         switch (addr) {
           case RTC_STAT_REGA:
             // toggle UIP bit for linux
             stat_regA ^= RTCA_UIP;
             return stat_regA;
             break;
           case RTC_STAT_REGB:
             return stat_regB;
             break;
           case RTC_STAT_REGC:
           case RTC_STAT_REGD:
             return 0x00;
             break;
           default:
             panic("Shouldn't be here");
         }
     }
 }

 void
 MC146818::tickClock()
 {
     if (stat_regB & RTCB_NO_UPDT)
         return;
     time_t calTime = mkutctime(&curTime);
     calTime++;
     setTime(*gmtime(&calTime));
 }

 void
 MC146818::serialize(const string &base, ostream &os)
 {
     arrayParamOut(os, base + ".clock_data", clock_data, sizeof(clock_data));
     paramOut(os, base + ".stat_regA", stat_regA);
     paramOut(os, base + ".stat_regB", stat_regB);

     //
     // save the timer tick and rtc clock tick values to correctly reschedule
     // them during unserialize
     //
     Tick rtcTimerInterruptTickOffset = event.when() - curTick();
     SERIALIZE_SCALAR(rtcTimerInterruptTickOffset);
     Tick rtcClockTickOffset = tickEvent.when() - curTick();
     SERIALIZE_SCALAR(rtcClockTickOffset);
 }

 void
 MC146818::unserialize(const string &base, Checkpoint *cp,
                       const string &section)
 {
     arrayParamIn(cp, section, base + ".clock_data", clock_data,
                  sizeof(clock_data));
     paramIn(cp, section, base + ".stat_regA", stat_regA);
     paramIn(cp, section, base + ".stat_regB", stat_regB);

     //
     // properly schedule the timer and rtc clock events
     //
     Tick rtcTimerInterruptTickOffset;
     UNSERIALIZE_SCALAR(rtcTimerInterruptTickOffset);
     reschedule(event, curTick() + rtcTimerInterruptTickOffset);
     Tick rtcClockTickOffset;
     UNSERIALIZE_SCALAR(rtcClockTickOffset);
     reschedule(tickEvent, curTick() + rtcClockTickOffset);
 }

 MC146818::RTCEvent::RTCEvent(MC146818 * _parent, Tick i)
     : parent(_parent), interval(i)
 {
     DPRINTF(MC146818, "RTC Event Initilizing\n");
     parent->schedule(this, curTick() + interval);
 }

 void
 MC146818::RTCEvent::scheduleIntr()
 {
     parent->schedule(this, curTick() + interval);
 }

 void
 MC146818::RTCEvent::process()
 {
     DPRINTF(MC146818, "RTC Timer Interrupt\n");
     parent->schedule(this, curTick() + interval);
     parent->handleEvent();
 }

 const char *
 MC146818::RTCEvent::description() const
 {
     return "RTC interrupt";
 }

 void
 MC146818::RTCTickEvent::process()
 {
     DPRINTF(MC146818, "RTC clock tick\n");
     parent->schedule(this, curTick() + SimClock::Int::s);
     parent->tickClock();
 }

 const char *
 MC146818::RTCTickEvent::description() const
 {
     return "RTC clock tick";
 }
	/*
	* Copyright (c) 2004-2005 The Regents of The University of Michigan
	* All rights reserved.
	*
	* 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
	* Andrew Schultz
	* Miguel Serrano
	*/

	#include <sys/time.h>

	#include <ctime>
	#include <string>

	#include "base/bitfield.hh"
	#include "base/time.hh"
	#include "base/trace.hh"
	#include "debug/MC146818.hh"
	#include "dev/mc146818.hh"
	#include "dev/rtcreg.h"

	using namespace std;

	static uint8_t
	bcdize(uint8_t val)
	{
	uint8_t result;
	result = val % 10;
	result += (val / 10) << 4;
	return result;
	}

	static uint8_t
	unbcdize(uint8_t val)
	{
	uint8_t result;
	result = val & 0xf;
	result += (val >> 4) * 10;
	return result;
	}

	void
	MC146818::setTime(const struct tm time)
	{
	curTime = time;
	year = time.tm_year;
	// Unix is 0-11 for month, data seet says start at 1
	mon = time.tm_mon + 1;
	mday = time.tm_mday;
	hour = time.tm_hour;
	min = time.tm_min;
	sec = time.tm_sec;

	// Datasheet says 1 is sunday
	wday = time.tm_wday + 1;

	if (!(stat_regB & RTCB_BIN)) {
	// The datasheet says that the year field can be either BCD or
	// years since 1900. Linux seems to be happy with years since
	// 1900.
	year = bcdize(year % 100);
	mon = bcdize(mon);
	mday = bcdize(mday);
	hour = bcdize(hour);
	min = bcdize(min);
	sec = bcdize(sec);
	}
	}

	MC146818::MC146818(EventManager *em, const string &n, const struct tm time,
	bool bcd, Tick frequency)
	: EventManager(em), _name(n), event(this, frequency), tickEvent(this)
	{
	memset(clock_data, 0, sizeof(clock_data));
	stat_regA = RTCA_32768HZ \| RTCA_1024HZ;
	stat_regB = RTCB_PRDC_IE \| RTCB_24HR;
	if (!bcd)
	stat_regB \|= RTCB_BIN;

	setTime(time);
	DPRINTFN("Real-time clock set to %s", asctime(&time));
	}

	MC146818::~MC146818()
	{
	deschedule(tickEvent);
	deschedule(event);
	}

	void
	MC146818::writeData(const uint8_t addr, const uint8_t data)
	{
	if (addr < RTC_STAT_REGA) {
	clock_data[addr] = data;
	curTime.tm_sec = unbcdize(sec);
	curTime.tm_min = unbcdize(min);
	curTime.tm_hour = unbcdize(hour);
	curTime.tm_mday = unbcdize(mday);
	curTime.tm_mon = unbcdize(mon) - 1;
	curTime.tm_year = ((unbcdize(year) + 50) % 100) + 1950;
	curTime.tm_wday = unbcdize(wday) - 1;
	} else {
	switch (addr) {
	case RTC_STAT_REGA:
	// The "update in progress" bit is read only.
	if ((data & ~RTCA_UIP) != (RTCA_32768HZ \| RTCA_1024HZ))
	panic("Unimplemented RTC register A value write!\n");
	replaceBits(stat_regA, data, 6, 0);
	break;
	case RTC_STAT_REGB:
	if ((data & ~(RTCB_PRDC_IE \| RTCB_SQWE)) != RTCB_24HR)
	panic("Write to RTC reg B bits that are not implemented!\n");

	if (data & RTCB_PRDC_IE) {
	if (!event.scheduled())
	event.scheduleIntr();
	} else {
	if (event.scheduled())
	deschedule(event);
	}
	stat_regB = data;
	break;
	case RTC_STAT_REGC:
	case RTC_STAT_REGD:
	panic("RTC status registers C and D are not implemented.\n");
	break;
	}
	}
	}

	uint8_t
	MC146818::readData(uint8_t addr)
	{
	if (addr < RTC_STAT_REGA)
	return clock_data[addr];
	else {
	switch (addr) {
	case RTC_STAT_REGA:
	// toggle UIP bit for linux
	stat_regA ^= RTCA_UIP;
	return stat_regA;
	break;
	case RTC_STAT_REGB:
	return stat_regB;
	break;
	case RTC_STAT_REGC:
	case RTC_STAT_REGD:
	return 0x00;
	break;
	default:
	panic("Shouldn't be here");
	}
	}
	}

	void
	MC146818::tickClock()
	{
	if (stat_regB & RTCB_NO_UPDT)
	return;
	time_t calTime = mkutctime(&curTime);
	calTime++;
	setTime(*gmtime(&calTime));
	}

	void
	MC146818::serialize(const string &base, ostream &os)
	{
	arrayParamOut(os, base + ".clock_data", clock_data, sizeof(clock_data));
	paramOut(os, base + ".stat_regA", stat_regA);
	paramOut(os, base + ".stat_regB", stat_regB);

	//
	// save the timer tick and rtc clock tick values to correctly reschedule
	// them during unserialize
	//
	Tick rtcTimerInterruptTickOffset = event.when() - curTick();
	SERIALIZE_SCALAR(rtcTimerInterruptTickOffset);
	Tick rtcClockTickOffset = tickEvent.when() - curTick();
	SERIALIZE_SCALAR(rtcClockTickOffset);
	}

	void
	MC146818::unserialize(const string &base, Checkpoint *cp,
	const string &section)
	{
	arrayParamIn(cp, section, base + ".clock_data", clock_data,
	sizeof(clock_data));
	paramIn(cp, section, base + ".stat_regA", stat_regA);
	paramIn(cp, section, base + ".stat_regB", stat_regB);

	//
	// properly schedule the timer and rtc clock events
	//
	Tick rtcTimerInterruptTickOffset;
	UNSERIALIZE_SCALAR(rtcTimerInterruptTickOffset);
	reschedule(event, curTick() + rtcTimerInterruptTickOffset);
	Tick rtcClockTickOffset;
	UNSERIALIZE_SCALAR(rtcClockTickOffset);
	reschedule(tickEvent, curTick() + rtcClockTickOffset);
	}

	MC146818::RTCEvent::RTCEvent(MC146818 * _parent, Tick i)
	: parent(_parent), interval(i)
	{
	DPRINTF(MC146818, "RTC Event Initilizing\n");
	parent->schedule(this, curTick() + interval);
	}

	void
	MC146818::RTCEvent::scheduleIntr()
	{
	parent->schedule(this, curTick() + interval);
	}

	void
	MC146818::RTCEvent::process()
	{
	DPRINTF(MC146818, "RTC Timer Interrupt\n");
	parent->schedule(this, curTick() + interval);
	parent->handleEvent();
	}

	const char *
	MC146818::RTCEvent::description() const
	{
	return "RTC interrupt";
	}

	void
	MC146818::RTCTickEvent::process()
	{
	DPRINTF(MC146818, "RTC clock tick\n");
	parent->schedule(this, curTick() + SimClock::Int::s);
	parent->tickClock();
	}

	const char *
	MC146818::RTCTickEvent::description() const
	{
	return "RTC clock tick";
	}