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Diffstat (limited to 'src/dev/mc146818.cc')
| -rw-r--r-- | src/dev/mc146818.cc | 184 |
1 files changed, 184 insertions, 0 deletions
diff --git a/src/dev/mc146818.cc b/src/dev/mc146818.cc new file mode 100644 index 000000000..984422105 --- /dev/null +++ b/src/dev/mc146818.cc @@ -0,0 +1,184 @@ +/* + * 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(const string &n, const struct tm time, + bool bcd, Tick frequency) + : _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)); +} + +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()) + event.deschedule(); + } + 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 §ion) +{ + 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 + event.reschedule(curTick + event.interval); +} + +MC146818::RTCEvent::RTCEvent(MC146818 * _parent, Tick i) + : Event(&mainEventQueue), parent(_parent), interval(i) +{ + DPRINTF(MC146818, "RTC Event Initilizing\n"); + schedule(curTick + interval); +} + +void +MC146818::RTCEvent::scheduleIntr() +{ + schedule(curTick + interval); +} + +void +MC146818::RTCEvent::process() +{ + DPRINTF(MC146818, "RTC Timer Interrupt\n"); + schedule(curTick + interval); + parent->handleEvent(); +} + +const char * +MC146818::RTCEvent::description() const +{ + return "RTC interrupt"; +} |