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+/*
+ * 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 &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
+ 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";
+}