tsunami_io.cc

来自「M5,一个功能强大的多处理器系统模拟器.很多针对处理器架构,性能的研究都使用它作」· CC 代码 · 共 660 行 · 第 1/2 页

/*
 * Copyright (c) 2004, 2005
 * The Regents of The University of Michigan
 * All Rights Reserved
 *
 * This code is part of the M5 simulator.
 *
 * Permission is granted to use, copy, create derivative works and
 * redistribute this software and such derivative works for any
 * purpose, so long as the copyright notice above, this grant of
 * permission, and the disclaimer below appear in all copies made; and
 * so long as the name of The University of Michigan is not used in
 * any advertising or publicity pertaining to the use or distribution
 * of this software without specific, written prior authorization.
 *
 * THIS SOFTWARE IS PROVIDED AS IS, WITHOUT REPRESENTATION FROM THE
 * UNIVERSITY OF MICHIGAN AS TO ITS FITNESS FOR ANY PURPOSE, AND
 * WITHOUT WARRANTY BY THE UNIVERSITY OF MICHIGAN OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE. THE REGENTS OF THE UNIVERSITY OF MICHIGAN SHALL NOT BE
 * LIABLE FOR ANY DAMAGES, INCLUDING DIRECT, SPECIAL, INDIRECT,
 * INCIDENTAL, OR CONSEQUENTIAL DAMAGES, WITH RESPECT TO ANY CLAIM
 * ARISING OUT OF OR IN CONNECTION WITH THE USE OF THE SOFTWARE, EVEN
 * IF IT HAS BEEN OR IS HEREAFTER ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGES.
 *
 * Authors: Ali G. Saidi
 *          Andrew L. Schultz
 *          Miguel J. Serrano
 */

/** @file
 * Tsunami I/O including PIC, PIT, RTC, DMA
 */

#include <sys/time.h>

#include <deque>
#include <string>
#include <vector>

#include "base/time.hh"
#include "base/trace.hh"
#include "dev/pitreg.h"
#include "dev/rtcreg.h"
#include "dev/alpha/tsunami_cchip.hh"
#include "dev/alpha/tsunami.hh"
#include "dev/alpha/tsunami_io.hh"
#include "dev/alpha/tsunamireg.h"
#include "mem/packet.hh"
#include "mem/packet_access.hh"
#include "mem/port.hh"
#include "sim/system.hh"

using namespace std;
//Should this be AlphaISA?
using namespace TheISA;

TsunamiIO::RTC::RTC(const string &n, Tsunami* tsunami,
                    const TsunamiIO::Params *p)
    : _name(n), event(tsunami, p->frequency), addr(0)
{
    memset(clock_data, 0, sizeof(clock_data));
    stat_regA = RTCA_32768HZ | RTCA_1024HZ;
    stat_regB = RTCB_PRDC_IE |RTCB_BIN | RTCB_24HR;

    year = p->time.tm_year;

    if (p->year_is_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 = p->time.tm_mon + 1;
    mday = p->time.tm_mday;
    hour = p->time.tm_hour;
    min = p->time.tm_min;
    sec = p->time.tm_sec;

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

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

void
TsunamiIO::RTC::writeAddr(const uint8_t data)
{
    if (data <= RTC_STAT_REGD)
        addr = data;
    else
        panic("RTC addresses over 0xD are not implemented.\n");
}

void
TsunamiIO::RTC::writeData(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
TsunamiIO::RTC::readData()
{
    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
TsunamiIO::RTC::serialize(const string &base, ostream &os)
{
    paramOut(os, base + ".addr", addr);
    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
TsunamiIO::RTC::unserialize(const string &base, Checkpoint *cp,
                            const string &section)
{
    paramIn(cp, section, base + ".addr", addr);
    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);
}

TsunamiIO::RTC::RTCEvent::RTCEvent(Tsunami*t, Tick i)
    : Event(&mainEventQueue), tsunami(t), interval(i)
{
    DPRINTF(MC146818, "RTC Event Initilizing\n");
    schedule(curTick + interval);
}

void
TsunamiIO::RTC::RTCEvent::scheduleIntr()
{
  schedule(curTick + interval);
}

void
TsunamiIO::RTC::RTCEvent::process()
{
    DPRINTF(MC146818, "RTC Timer Interrupt\n");
    schedule(curTick + interval);
    //Actually interrupt the processor here
    tsunami->cchip->postRTC();
}

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

TsunamiIO::PITimer::PITimer(const string &name)
    : _name(name), counter0(name + ".counter0"), counter1(name + ".counter1"),
      counter2(name + ".counter2")
{
    counter[0] = &counter0;
    counter[1] = &counter0;
    counter[2] = &counter0;
}

void
TsunamiIO::PITimer::writeControl(const uint8_t data)
{
    int rw;
    int sel;

    sel = GET_CTRL_SEL(data);

    if (sel == PIT_READ_BACK)
       panic("PITimer Read-Back Command is not implemented.\n");

    rw = GET_CTRL_RW(data);

    if (rw == PIT_RW_LATCH_COMMAND)
        counter[sel]->latchCount();
    else {
        counter[sel]->setRW(rw);
        counter[sel]->setMode(GET_CTRL_MODE(data));
        counter[sel]->setBCD(GET_CTRL_BCD(data));
    }
}

void
TsunamiIO::PITimer::serialize(const string &base, ostream &os)
{
    // serialize the counters
    counter0.serialize(base + ".counter0", os);
    counter1.serialize(base + ".counter1", os);
    counter2.serialize(base + ".counter2", os);
}

void
TsunamiIO::PITimer::unserialize(const string &base, Checkpoint *cp,
                                const string &section)
{
    // unserialze the counters
    counter0.unserialize(base + ".counter0", cp, section);
    counter1.unserialize(base + ".counter1", cp, section);
    counter2.unserialize(base + ".counter2", cp, section);
}

TsunamiIO::PITimer::Counter::Counter(const string &name)
    : _name(name), event(this), count(0), latched_count(0), period(0),
      mode(0), output_high(false), latch_on(false), read_byte(LSB),
      write_byte(LSB)
{

}

void
TsunamiIO::PITimer::Counter::latchCount()
{
    // behave like a real latch
    if(!latch_on) {
        latch_on = true;
        read_byte = LSB;
        latched_count = count;
    }
}

uint8_t
TsunamiIO::PITimer::Counter::read()
{
    if (latch_on) {
        switch (read_byte) {
          case LSB:
            read_byte = MSB;
            return (uint8_t)latched_count;
            break;
          case MSB:
            read_byte = LSB;
            latch_on = false;
            return latched_count >> 8;
            break;
          default:
            panic("Shouldn't be here");
        }
    } else {
        switch (read_byte) {
          case LSB:
            read_byte = MSB;
            return (uint8_t)count;
            break;
          case MSB:
            read_byte = LSB;
            return count >> 8;
            break;
          default:
            panic("Shouldn't be here");
        }
    }
}

void
TsunamiIO::PITimer::Counter::write(const uint8_t data)
{
    switch (write_byte) {
      case LSB:
        count = (count & 0xFF00) | data;

        if (event.scheduled())
          event.deschedule();
        output_high = false;
        write_byte = MSB;
        break;

      case MSB:
        count = (count & 0x00FF) | (data << 8);
        period = count;