NowindInterface.cc

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#include "NowindInterface.hh"
#include "DiskChanger.hh"
#include "Clock.hh"
#include "MSXMotherBoard.hh"
#include "MSXException.hh"
#include "narrow.hh"
#include "serialize.hh"
#include "serialize_stl.hh"
#include <cassert>
#include <functional>
#include <memory>
 
namespace openmsx {
 
NowindInterface::NowindInterface(const DeviceConfig& config)
        : MSXDevice(config)
        , rom(getName() + " ROM", "rom", config)
        , flash(rom, AmdFlashChip::AM29F040, {}, config)
        , host(drives)
        , basename("nowindX")
{
        if ((rom.size() % 0x4000) != 0) {
                throw MSXException("NowindInterface ROM size must be a multiple of 16kB");
        }
        if (rom.size() == 0) {
                throw MSXException("NowindInterface ROM size cannot be zero");
        }
        if (rom.size() > size_t(256 * 0x4000)) {
                throw MSXException("NowindInterface ROM size cannot be larger than 4MB");
        }
 
        nowindsInUse = getMotherBoard().getSharedStuff<NowindsInUse>("nowindsInUse");
 
        unsigned i = 0;
        while ((*nowindsInUse)[i]) {
                if (++i == MAX_NOWINDS) {
                        throw MSXException("Too many nowind interfaces.");
                }
        }
        (*nowindsInUse)[i] = true;
        basename[6] = char('a' + i);
 
        command.emplace(basename, getCommandController(), *this);
 
        // start with one (empty) drive
        auto drive = command->createDiskChanger(basename, 0, getMotherBoard());
        drive->createCommand();
        drives.push_back(std::move(drive));
 
        reset(EmuTime::dummy());
}
 
NowindInterface::~NowindInterface()
{
        unsigned i = basename[6] - 'a';
        assert((*nowindsInUse)[i]);
        (*nowindsInUse)[i] = false;
}
 
void NowindInterface::reset(EmuTime::param /*time*/)
{
        // version 1 didn't change the bank number
        // version 2 (produced by Sunrise) does reset the bank number
        bank = 0;
 
        // Flash state is NOT changed on reset
        //flash.reset();
}
 
byte NowindInterface::peekMem(word address, EmuTime::param /*time*/) const
{
        if (((0x2000 <= address) && (address < 0x4000)) ||
            ((0x8000 <= address) && (address < 0xA000))) {
                return host.peek();
        } else if ((0x4000 <= address) && (address < 0xC000)) {
                // note: range 0x8000-0xA000 is already handled above
                return flash.peek(bank * 0x4000 + (address & 0x3FFF));
        } else {
                return 0xFF;
        }
}
 
byte NowindInterface::readMem(word address, EmuTime::param /*time*/)
{
        if (((0x2000 <= address) && (address < 0x4000)) ||
            ((0x8000 <= address) && (address < 0xA000))) {
                return host.read();
        } else if ((0x4000 <= address) && (address < 0xC000)) {
                // note: range 0x8000-0xA000 is already handled above
                return flash.read(bank * 0x4000 + (address & 0x3FFF));
        } else {
                return 0xFF;
        }
}
 
const byte* NowindInterface::getReadCacheLine(word address) const
{
        if (((0x2000 <= address) && (address < 0x4000)) ||
            ((0x8000 <= address) && (address < 0xA000))) {
                // nowind region, not cacheable
                return nullptr;
        } else if ((0x4000 <= address) && (address < 0xC000)) {
                // note: range 0x8000-0xA000 is already handled above
                return flash.getReadCacheLine(bank * 0x4000 + (address & 0x3FFF));
        } else {
                return unmappedRead.data();
        }
}
 
void NowindInterface::writeMem(word address, byte value, EmuTime::param time)
{
        if (address < 0x4000) {
                flash.write(bank * 0x4000 + address, value);
        } else if (((0x4000 <= address) && (address < 0x6000)) ||
                   ((0x8000 <= address) && (address < 0xA000))) {
                constexpr Clock<1000> clock(EmuTime::zero());
                host.write(value, clock.getTicksTill(time));
        } else if (((0x6000 <= address) && (address < 0x8000)) ||
                   ((0xA000 <= address) && (address < 0xC000))) {
                auto max = narrow<uint8_t>((rom.size() / 0x4000) - 1);
                bank = (value <= max) ? value : (value & max);
                invalidateDeviceRCache(0x4000, 0x4000);
                invalidateDeviceRCache(0xA000, 0x2000);
        }
}
 
byte* NowindInterface::getWriteCacheLine(word address)
{
        if (address < 0xC000) {
                // not cacheable
                return nullptr;
        } else {
                return unmappedWrite.data();
        }
}
 
 
template<typename Archive>
void NowindInterface::serialize(Archive& ar, unsigned /*version*/)
{
        ar.template serializeBase<MSXDevice>(*this);
        ar.serialize("flash", flash);
        ar.serializeWithID("drives", drives, std::ref(getMotherBoard()));
        ar.serialize("nowindhost", host,
                     "bank",       bank);
 
        // don't serialize command, rom, basename
}
INSTANTIATE_SERIALIZE_METHODS(NowindInterface);
REGISTER_MSXDEVICE(NowindInterface, "NowindInterface");
 
} // namespace openmsx