MSXCPU.cc

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#include "MSXCPU.hh"
#include "MSXMotherBoard.hh"
#include "Debugger.hh"
#include "Scheduler.hh"
#include "IntegerSetting.hh"
#include "CPUCore.hh"
#include "Z80.hh"
#include "R800.hh"
#include "TclObject.hh"
#include "outer.hh"
#include "serialize.hh"
#include "unreachable.hh"
#include <cassert>
#include <memory>

using std::string;
using std::vector;

namespace openmsx {

MSXCPU::MSXCPU(MSXMotherBoard& motherboard_)
        : motherboard(motherboard_)
        , traceSetting(
                motherboard.getCommandController(), "cputrace",
                "CPU tracing on/off", false, Setting::DONT_SAVE)
        , diHaltCallback(
                motherboard.getCommandController(), "di_halt_callback",
                "Tcl proc called when the CPU executed a DI/HALT sequence")
        , z80(std::make_unique<CPUCore<Z80TYPE>>(
                motherboard, "z80", traceSetting,
                diHaltCallback, EmuTime::zero))
        , r800(motherboard.isTurboR()
                ? std::make_unique<CPUCore<R800TYPE>>(
                        motherboard, "r800", traceSetting,
                        diHaltCallback, EmuTime::zero)
                : nullptr)
        , timeInfo(motherboard.getMachineInfoCommand())
        , z80FreqInfo(motherboard.getMachineInfoCommand(), "z80_freq", *z80)
        , r800FreqInfo(r800
                ? std::make_unique<CPUFreqInfoTopic>(
                        motherboard.getMachineInfoCommand(), "r800_freq", *r800)
                : nullptr)
        , debuggable(motherboard_)
        , reference(EmuTime::zero)
{
        z80Active = true; // setActiveCPU(CPU_Z80);
        newZ80Active = z80Active;

        motherboard.getDebugger().setCPU(this);
        motherboard.getScheduler().setCPU(this);
        traceSetting.attach(*this);

        z80->freqLocked.attach(*this);
        z80->freqValue.attach(*this);
        if (r800) {
                r800->freqLocked.attach(*this);
                r800->freqValue.attach(*this);
        }
}

MSXCPU::~MSXCPU()
{
        traceSetting.detach(*this);
        z80->freqLocked.detach(*this);
        z80->freqValue.detach(*this);
        if (r800) {
                r800->freqLocked.detach(*this);
                r800->freqValue.detach(*this);
        }
        motherboard.getScheduler().setCPU(nullptr);
        motherboard.getDebugger() .setCPU(nullptr);
}

void MSXCPU::setInterface(MSXCPUInterface* interface)
{
                  z80 ->setInterface(interface);
        if (r800) r800->setInterface(interface);
}

void MSXCPU::doReset(EmuTime::param time)
{
                  z80 ->doReset(time);
        if (r800) r800->doReset(time);

        reference = time;
}

void MSXCPU::setActiveCPU(CPUType cpu)
{
        if (cpu == CPU_R800) assert(r800);

        bool tmp = cpu == CPU_Z80;
        if (tmp != z80Active) {
                exitCPULoopSync();
                newZ80Active = tmp;
        }
}

void MSXCPU::setDRAMmode(bool dram)
{
        assert(r800);
        r800->setDRAMmode(dram);
}

void MSXCPU::execute(bool fastForward)
{
        if (z80Active != newZ80Active) {
                EmuTime time = getCurrentTime();
                z80Active = newZ80Active;
                z80Active ? z80 ->warp(time)
                          : r800->warp(time);
                invalidateMemCache(0x0000, 0x10000);
        }
        z80Active ? z80 ->execute(fastForward)
                  : r800->execute(fastForward);
}

void MSXCPU::exitCPULoopSync()
{
        z80Active ? z80 ->exitCPULoopSync()
                  : r800->exitCPULoopSync();
}
void MSXCPU::exitCPULoopAsync()
{
        z80Active ? z80 ->exitCPULoopAsync()
                  : r800->exitCPULoopAsync();
}

EmuTime::param MSXCPU::getCurrentTime() const
{
        return z80Active ? z80 ->getCurrentTime()
                         : r800->getCurrentTime();
}

void MSXCPU::setNextSyncPoint(EmuTime::param time)
{
        z80Active ? z80 ->setNextSyncPoint(time)
                  : r800->setNextSyncPoint(time);
}

void MSXCPU::updateVisiblePage(byte page, byte primarySlot, byte secondarySlot)
{
        invalidateMemCache(page * 0x4000, 0x4000);
        if (r800) r800->updateVisiblePage(page, primarySlot, secondarySlot);
}

void MSXCPU::invalidateMemCache(word start, unsigned size)
{
        z80Active ? z80 ->invalidateMemCache(start, size)
                  : r800->invalidateMemCache(start, size);
}

void MSXCPU::raiseIRQ()
{
                  z80 ->raiseIRQ();
        if (r800) r800->raiseIRQ();
}
void MSXCPU::lowerIRQ()
{
                  z80 ->lowerIRQ();
        if (r800) r800->lowerIRQ();
}
void MSXCPU::raiseNMI()
{
                  z80 ->raiseNMI();
        if (r800) r800->raiseNMI();
}
void MSXCPU::lowerNMI()
{
                  z80 ->lowerNMI();
        if (r800) r800->lowerNMI();
}

bool MSXCPU::isM1Cycle(unsigned address) const
{
        return z80Active ? z80 ->isM1Cycle(address)
                         : r800->isM1Cycle(address);
}

void MSXCPU::setZ80Freq(unsigned freq)
{
        z80->setFreq(freq);
}

void MSXCPU::wait(EmuTime::param time)
{
        z80Active ? z80 ->wait(time)
                  : r800->wait(time);
}

EmuTime MSXCPU::waitCycles(EmuTime::param time, unsigned cycles)
{
        return z80Active ? z80 ->waitCycles(time, cycles)
                         : r800->waitCycles(time, cycles);
}

EmuTime MSXCPU::waitCyclesR800(EmuTime::param time, unsigned cycles)
{
        return z80Active ? time
                         : r800->waitCycles(time, cycles);
}

CPURegs& MSXCPU::getRegisters()
{
        if (z80Active) {
                return *z80;
        } else {
                return *r800;
        }
}

void MSXCPU::update(const Setting& setting)
{
                  z80 ->update(setting);
        if (r800) r800->update(setting);
        exitCPULoopSync();
}

// Command

void MSXCPU::disasmCommand(
        Interpreter& interp, span<const TclObject> tokens,
        TclObject& result) const
{
        z80Active ? z80 ->disasmCommand(interp, tokens, result)
                  : r800->disasmCommand(interp, tokens, result);
}

void MSXCPU::setPaused(bool paused)
{
        if (z80Active) {
                z80 ->setExtHALT(paused);
                z80 ->exitCPULoopSync();
        } else {
                r800->setExtHALT(paused);
                r800->exitCPULoopSync();
        }
}


// class TimeInfoTopic

MSXCPU::TimeInfoTopic::TimeInfoTopic(InfoCommand& machineInfoCommand)
        : InfoTopic(machineInfoCommand, "time")
{
}

void MSXCPU::TimeInfoTopic::execute(
        span<const TclObject> /*tokens*/, TclObject& result) const
{
        auto& cpu = OUTER(MSXCPU, timeInfo);
        EmuDuration dur = cpu.getCurrentTime() - cpu.reference;
        result = dur.toDouble();
}

string MSXCPU::TimeInfoTopic::help(const vector<string>& /*tokens*/) const
{
        return "Prints the time in seconds that the MSX is powered on\n";
}


// class CPUFreqInfoTopic

MSXCPU::CPUFreqInfoTopic::CPUFreqInfoTopic(
                InfoCommand& machineInfoCommand,
                const string& name_, CPUClock& clock_)
        : InfoTopic(machineInfoCommand, name_)
        , clock(clock_)
{
}

void MSXCPU::CPUFreqInfoTopic::execute(
        span<const TclObject> /*tokens*/, TclObject& result) const
{
        result = clock.getFreq();
}

string MSXCPU::CPUFreqInfoTopic::help(const vector<string>& /*tokens*/) const
{
        return "Returns the actual frequency of this CPU.\n"
               "This frequency can vary because:\n"
               " - the user has overridden the freq via the '{z80,r800}_freq' setting\n"
               " - (only on some MSX machines) the MSX software can switch the Z80 between 2 frequencies\n"
               "See also the '{z80,r800}_freq_locked' setting.\n";
}


// class Debuggable

static const char* const CPU_REGS_DESC =
        "Registers of the active CPU (Z80 or R800).\n"
        "Each byte in this debuggable represents one 8 bit register:\n"
        "  0 ->  A      1 ->  F      2 -> B       3 -> C\n"
        "  4 ->  D      5 ->  E      6 -> H       7 -> L\n"
        "  8 ->  A'     9 ->  F'    10 -> B'     11 -> C'\n"
        " 12 ->  D'    13 ->  E'    14 -> H'     15 -> L'\n"
        " 16 -> IXH    17 -> IXL    18 -> IYH    19 -> IYL\n"
        " 20 -> PCH    21 -> PCL    22 -> SPH    23 -> SPL\n"
        " 24 ->  I     25 ->  R     26 -> IM     27 -> IFF1/2\n"
        "The last position (27) contains the IFF1 and IFF2 flags in respectively\n"
        "bit 0 and 1. Bit 2 contains 'IFF1 AND last-instruction-was-not-EI', so\n"
        "this effectively indicates that the CPU could accept an interrupt at\n"
        "the start of the current instruction.\n";

MSXCPU::Debuggable::Debuggable(MSXMotherBoard& motherboard_)
        : SimpleDebuggable(motherboard_, "CPU regs", CPU_REGS_DESC, 28)
{
}

byte MSXCPU::Debuggable::read(unsigned address)
{
        auto& cpu = OUTER(MSXCPU, debuggable);
        const CPURegs& regs = cpu.getRegisters();
        switch (address) {
        case  0: return regs.getA();
        case  1: return regs.getF();
        case  2: return regs.getB();
        case  3: return regs.getC();
        case  4: return regs.getD();
        case  5: return regs.getE();
        case  6: return regs.getH();
        case  7: return regs.getL();
        case  8: return regs.getA2();
        case  9: return regs.getF2();
        case 10: return regs.getB2();
        case 11: return regs.getC2();
        case 12: return regs.getD2();
        case 13: return regs.getE2();
        case 14: return regs.getH2();
        case 15: return regs.getL2();
        case 16: return regs.getIXh();
        case 17: return regs.getIXl();
        case 18: return regs.getIYh();
        case 19: return regs.getIYl();
        case 20: return regs.getPCh();
        case 21: return regs.getPCl();
        case 22: return regs.getSPh();
        case 23: return regs.getSPl();
        case 24: return regs.getI();
        case 25: return regs.getR();
        case 26: return regs.getIM();
        case 27: return 1 *  regs.getIFF1() +
                        2 *  regs.getIFF2() +
                        4 * (regs.getIFF1() && !regs.prevWasEI());
        default: UNREACHABLE; return 0;
        }
}

void MSXCPU::Debuggable::write(unsigned address, byte value)
{
        auto& cpu = OUTER(MSXCPU, debuggable);
        CPURegs& regs = cpu.getRegisters();
        switch (address) {
        case  0: regs.setA(value); break;
        case  1: regs.setF(value); break;
        case  2: regs.setB(value); break;
        case  3: regs.setC(value); break;
        case  4: regs.setD(value); break;
        case  5: regs.setE(value); break;
        case  6: regs.setH(value); break;
        case  7: regs.setL(value); break;
        case  8: regs.setA2(value); break;
        case  9: regs.setF2(value); break;
        case 10: regs.setB2(value); break;
        case 11: regs.setC2(value); break;
        case 12: regs.setD2(value); break;
        case 13: regs.setE2(value); break;
        case 14: regs.setH2(value); break;
        case 15: regs.setL2(value); break;
        case 16: regs.setIXh(value); break;
        case 17: regs.setIXl(value); break;
        case 18: regs.setIYh(value); break;
        case 19: regs.setIYl(value); break;
        case 20: regs.setPCh(value); break;
        case 21: regs.setPCl(value); break;
        case 22: regs.setSPh(value); break;
        case 23: regs.setSPl(value); break;
        case 24: regs.setI(value); break;
        case 25: regs.setR(value); break;
        case 26:
                if (value < 3) regs.setIM(value);
                break;
        case 27:
                regs.setIFF1((value & 0x01) != 0);
                regs.setIFF2((value & 0x02) != 0);
                // can't change afterEI
                break;
        default:
                UNREACHABLE;
        }
}

// version 1: initial version
// version 2: activeCPU,newCPU -> z80Active,newZ80Active
template<typename Archive>
void MSXCPU::serialize(Archive& ar, unsigned version)
{
        if (ar.versionAtLeast(version, 2)) {
                          ar.serialize("z80",  *z80);
                if (r800) ar.serialize("r800", *r800);
                ar.serialize("z80Active", z80Active);
                ar.serialize("newZ80Active", newZ80Active);
        } else {
                // backwards-compatibility
                assert(ar.isLoader());

                          ar.serializeWithID("z80",  *z80);
                if (r800) ar.serializeWithID("r800", *r800);
                CPUBase* activeCPU = nullptr;
                CPUBase* newCPU = nullptr;
                ar.serializePointerID("activeCPU", activeCPU);
                ar.serializePointerID("newCPU",    newCPU);
                z80Active = activeCPU == z80.get();
                if (newCPU) {
                        newZ80Active = newCPU == z80.get();
                } else {
                        newZ80Active = z80Active;
                }
        }
        ar.serialize("resetTime", reference);
}
INSTANTIATE_SERIALIZE_METHODS(MSXCPU);

} // namespace openmsx