/*
 * Copyright (c) 2006 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.
 */

#include "arch/sparc/miscregfile.hh"
#include "base/bitfield.hh"
#include "base/trace.hh"
#include "cpu/base.hh"
#include "cpu/thread_context.hh"

using namespace SparcISA;

void
MiscRegFile::setFSRegWithEffect(int miscReg, const MiscReg &val,
                                ThreadContext *tc)
{
    int64_t time;
    switch (miscReg) {
        /* Full system only ASRs */
      case MISCREG_SOFTINT:
        setReg(miscReg, val);;
        break;

      case MISCREG_SOFTINT_CLR:
        return setRegWithEffect(MISCREG_SOFTINT, ~val & softint, tc);
      case MISCREG_SOFTINT_SET:
        tc->getCpuPtr()->post_interrupt(soft_interrupt);
        return setRegWithEffect(MISCREG_SOFTINT, val | softint, tc);

      case MISCREG_TICK_CMPR:
        if (tickCompare == NULL)
            tickCompare = new TickCompareEvent(this, tc);
        setReg(miscReg, val);
        if ((tick_cmpr & mask(63)) && tickCompare->scheduled())
            tickCompare->deschedule();
        time = (tick_cmpr & mask(63)) - (tick & mask(63));
        if (!(tick_cmpr & ~mask(63)) && time > 0)
            tickCompare->schedule(time * tc->getCpuPtr()->cycles(1));
        panic("writing to TICK compare register %#X\n", val);
        break;

      case MISCREG_STICK_CMPR:
        if (sTickCompare == NULL)
            sTickCompare = new STickCompareEvent(this, tc);
        setReg(miscReg, val);
        if ((stick_cmpr & ~mask(63)) && sTickCompare->scheduled())
            sTickCompare->deschedule();
        time = ((int64_t)(stick_cmpr & mask(63)) - (int64_t)stick) -
            tc->getCpuPtr()->instCount();
        if (!(stick_cmpr & ~mask(63)) && time > 0)
            sTickCompare->schedule(time * tc->getCpuPtr()->cycles(1) + curTick);
        DPRINTF(Timer, "writing to sTICK compare register value %#X\n", val);
        break;

      case MISCREG_PSTATE:
        setReg(miscReg, val);

      case MISCREG_PIL:
        setReg(miscReg, val);
        break;

      case MISCREG_HVER:
        panic("Shouldn't be writing HVER\n");

      case MISCREG_HINTP:
        setReg(miscReg, val);

      case MISCREG_HTBA:
        // clear lower 7 bits on writes.
        setReg(miscReg, val & ULL(~0x7FFF));
        break;

      case MISCREG_QUEUE_CPU_MONDO_HEAD:
      case MISCREG_QUEUE_CPU_MONDO_TAIL:
      case MISCREG_QUEUE_DEV_MONDO_HEAD:
      case MISCREG_QUEUE_DEV_MONDO_TAIL:
      case MISCREG_QUEUE_RES_ERROR_HEAD:
      case MISCREG_QUEUE_RES_ERROR_TAIL:
      case MISCREG_QUEUE_NRES_ERROR_HEAD:
      case MISCREG_QUEUE_NRES_ERROR_TAIL:
        setReg(miscReg, val);
        //do something to post mondo interrupt
        break;

      case MISCREG_HSTICK_CMPR:
        if (hSTickCompare == NULL)
            hSTickCompare = new HSTickCompareEvent(this, tc);
        setReg(miscReg, val);
        if ((hstick_cmpr & ~mask(63)) && hSTickCompare->scheduled())
            hSTickCompare->deschedule();
        time = ((int64_t)(hstick_cmpr & mask(63)) - (int64_t)stick) -
            tc->getCpuPtr()->instCount();
        if (!(hstick_cmpr & ~mask(63)) && time > 0)
            hSTickCompare->schedule(curTick + time * tc->getCpuPtr()->cycles(1));
        DPRINTF(Timer, "writing to hsTICK compare register value %#X\n", val);
        break;

      case MISCREG_HPSTATE:
        // T1000 spec says impl. dependent val must always be 1
        setReg(miscReg, val | HPSTATE::id);
        break;
      case MISCREG_HTSTATE:
      case MISCREG_STRAND_STS_REG:
        setReg(miscReg, val);
        break;

      default:
        panic("Invalid write to FS misc register %s\n", getMiscRegName(miscReg));
    }
}

MiscReg
MiscRegFile::readFSRegWithEffect(int miscReg, ThreadContext * tc)
{
    switch (miscReg) {
        /* Privileged registers. */
      case MISCREG_QUEUE_CPU_MONDO_HEAD:
      case MISCREG_QUEUE_CPU_MONDO_TAIL:
      case MISCREG_QUEUE_DEV_MONDO_HEAD:
      case MISCREG_QUEUE_DEV_MONDO_TAIL:
      case MISCREG_QUEUE_RES_ERROR_HEAD:
      case MISCREG_QUEUE_RES_ERROR_TAIL:
      case MISCREG_QUEUE_NRES_ERROR_HEAD:
      case MISCREG_QUEUE_NRES_ERROR_TAIL:
      case MISCREG_SOFTINT:
      case MISCREG_TICK_CMPR:
      case MISCREG_STICK_CMPR:
      case MISCREG_PIL:
      case MISCREG_HPSTATE:
      case MISCREG_HINTP:
      case MISCREG_HTSTATE:
      case MISCREG_STRAND_STS_REG:
      case MISCREG_HSTICK_CMPR:
        return readReg(miscReg) ;

      case MISCREG_HTBA:
        return readReg(miscReg) & ULL(~0x7FFF);
      case MISCREG_HVER:
        return NWindows | MaxTL << 8 | MaxGL << 16;

      default:
        panic("Invalid read to FS misc register\n");
    }
}
/*
  In Niagra STICK==TICK so this isn't needed
  case MISCREG_STICK:
  SparcSystem *sys;
  sys = dynamic_cast<SparcSystem*>(tc->getSystemPtr());
  assert(sys != NULL);
  return curTick/Clock::Int::ns - sys->sysTick | (stick & ~(mask(63)));
*/



void
MiscRegFile::processTickCompare(ThreadContext *tc)
{
    panic("tick compare not implemented\n");
}

void
MiscRegFile::processSTickCompare(ThreadContext *tc)
{
    // since our microcode instructions take two cycles we need to check if
    // we're actually at the correct cycle or we need to wait a little while
    // more
    int ticks;
    ticks = ((int64_t)(stick_cmpr & mask(63)) - (int64_t)stick) -
        tc->getCpuPtr()->instCount();
    assert(ticks >= 0 && "stick compare missed interrupt cycle");

    if (ticks == 0) {
        DPRINTF(Timer, "STick compare cycle reached at %#x\n",
                (stick_cmpr & mask(63)));
        if (!(tc->readMiscReg(MISCREG_STICK_CMPR) & (ULL(1) << 63))) {
            tc->getCpuPtr()->post_interrupt(soft_interrupt);
            setRegWithEffect(MISCREG_SOFTINT, softint | (ULL(1) << 16), tc);
        }
    } else
        sTickCompare->schedule(ticks * tc->getCpuPtr()->cycles(1) + curTick);
}

void
MiscRegFile::processHSTickCompare(ThreadContext *tc)
{
    // since our microcode instructions take two cycles we need to check if
    // we're actually at the correct cycle or we need to wait a little while
    // more
    int ticks;
    ticks = ((int64_t)(hstick_cmpr & mask(63)) - (int64_t)stick) -
        tc->getCpuPtr()->instCount();
    assert(ticks >= 0 && "hstick compare missed interrupt cycle");

    if (ticks == 0) {
        DPRINTF(Timer, "HSTick compare cycle reached at %#x\n",
                (stick_cmpr & mask(63)));
        if (!(tc->readMiscReg(MISCREG_HSTICK_CMPR) & (ULL(1) << 63))) {
            setRegWithEffect(MISCREG_HINTP, 1, tc);
            tc->getCpuPtr()->post_interrupt(hstick_match);
        }
        // Need to do something to cause interrupt to happen here !!! @todo
    } else
        sTickCompare->schedule(ticks * tc->getCpuPtr()->cycles(1) + curTick);
}