gem5/src/dev/mc146818.cc
Nathan Binkert e06321091d eventq: convert all usage of events to use the new API.
For now, there is still a single global event queue, but this is
necessary for making the steps towards a parallelized m5.
2008-10-09 04:58:24 -07:00

188 lines
5.6 KiB
C++

/*
* 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 <time.h>
#include <string>
#include "base/time.hh"
#include "base/trace.hh"
#include "dev/mc146818.hh"
#include "dev/rtcreg.h"
using namespace std;
MC146818::MC146818(EventManager *em, const string &n, const struct tm time,
bool bcd, Tick frequency)
: EventManager(em), _name(n), event(this, frequency)
{
memset(clock_data, 0, sizeof(clock_data));
stat_regA = RTCA_32768HZ | RTCA_1024HZ;
stat_regB = RTCB_PRDC_IE |RTCB_BIN | RTCB_24HR;
year = time.tm_year;
if (bcd) {
// 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 = year % 100;
int tens = year / 10;
int ones = year % 10;
year = (tens << 4) + ones;
}
// 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;
DPRINTFN("Real-time clock set to %s", asctime(&time));
}
MC146818::~MC146818()
{
}
void
MC146818::writeData(const uint8_t addr, const uint8_t data)
{
if (addr < RTC_STAT_REGA)
clock_data[addr] = data;
else {
switch (addr) {
case RTC_STAT_REGA:
if (data != (RTCA_32768HZ | RTCA_1024HZ))
panic("Unimplemented RTC register A value write!\n");
stat_regA = data;
break;
case RTC_STAT_REGB:
if ((data & ~(RTCB_PRDC_IE | RTCB_SQWE)) != (RTCB_BIN | 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::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);
}
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);
// We're not unserializing the event here, but we need to
// rescehedule the event since curTick was moved forward by the
// checkpoint
reschedule(event, curTick + event.interval);
}
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";
}