OXYGENHUB
◆ main openmsx / src / cpu / IRQHelper.cc
1.2 KiB · C++ · last changed chore(): initial commit 1 month ago source blame history raw
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#include "IRQHelper.hh"
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#include "DeviceConfig.hh"
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#include "MSXCPU.hh"
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#include "MSXException.hh"
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#include "one_of.hh"
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#include "unreachable.hh"
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namespace openmsx {
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// class IRQSource
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IRQSource::IRQSource(MSXCPU& cpu_)
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	: cpu(cpu_)
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{
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}
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void IRQSource::raise()
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{
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	cpu.raiseIRQ();
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}
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void IRQSource::lower()
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{
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	cpu.lowerIRQ();
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}
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// class OptionalIRQ
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OptionalIRQ::OptionalIRQ(MSXCPU& cpu_, const DeviceConfig& config)
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	: cpu(cpu_)
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	, type([&] {
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		auto connected = config.getChildData("irq_connected", "irq");
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		if (connected == one_of("irq", "true")) {
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			return Maskable;
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		} else if (connected == "nmi") {
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			return NonMaskable;
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		} else if (connected == "false") {
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			return NotConnected;
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		} else {
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			throw MSXException(
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				"Unknown IRQ sink \"", connected, "\" in <irq_connected>");
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		}
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	}())
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{
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}
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void OptionalIRQ::raise()
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{
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	switch (type) {
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		case NotConnected:
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			// nothing
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			break;
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		case Maskable:
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			cpu.raiseIRQ();
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			break;
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		case NonMaskable:
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			cpu.raiseNMI();
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			break;
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		default:
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			UNREACHABLE;
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	}
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}
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void OptionalIRQ::lower()
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{
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	switch (type) {
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		case NotConnected:
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			// nothing
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			break;
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		case Maskable:
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			cpu.lowerIRQ();
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			break;
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		case NonMaskable:
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			cpu.lowerNMI();
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			break;
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		default:
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			UNREACHABLE;
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	}
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}
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} // namespace openmsx