IRQHelper.cc

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#include "IRQHelper.hh"
#include "DeviceConfig.hh"
#include "MSXCPU.hh"
#include "MSXException.hh"
#include "one_of.hh"
#include "unreachable.hh"
 
namespace openmsx {
 
// class IRQSource
 
IRQSource::IRQSource(MSXCPU& cpu_)
        : cpu(cpu_)
{
}
 
void IRQSource::raise()
{
        cpu.raiseIRQ();
}
 
void IRQSource::lower()
{
        cpu.lowerIRQ();
}
 
 
// class OptionalIRQ
 
OptionalIRQ::OptionalIRQ(MSXCPU& cpu_, const DeviceConfig& config)
        : cpu(cpu_)
        , type([&] {
                auto connected = config.getChildData("irq_connected", "irq");
                if (connected == one_of("irq", "true")) {
                        return Maskable;
                } else if (connected == "nmi") {
                        return NonMaskable;
                } else if (connected == "false") {
                        return NotConnected;
                } else {
                        throw MSXException(
                                "Unknown IRQ sink \"", connected, "\" in <irq_connected>");
                }
        }())
{
}
 
void OptionalIRQ::raise()
{
        switch (type) {
                case NotConnected:
                        // nothing
                        break;
                case Maskable:
                        cpu.raiseIRQ();
                        break;
                case NonMaskable:
                        cpu.raiseNMI();
                        break;
                default:
                        UNREACHABLE;
        }
}
 
void OptionalIRQ::lower()
{
        switch (type) {
                case NotConnected:
                        // nothing
                        break;
                case Maskable:
                        cpu.lowerIRQ();
                        break;
                case NonMaskable:
                        cpu.lowerNMI();
                        break;
                default:
                        UNREACHABLE;
        }
}
 
} // namespace openmsx