thor: Implement interrupt NAK mechanism

Fixes #7.

drivers/block/ata/src/main.cpp

@@ -121,15 +121,17 @@ COFIBER_ROUTINE(cofiber::no_future, Controller::_handleIrqs(), ([=] {
 
 		// Check if the device is ready without clearing the IRQ.
 		auto status = _altSpace.load(alt_regs::inStatus);
-		if(status & kStatusBsy)
+		if(status & kStatusBsy) {
+			HEL_CHECK(helAcknowledgeIrq(_irq.getHandle(), kHelAckNack, sequence));
 			continue;
+		}
 		assert(!(status & (kStatusErr | kStatusDf)));
 		assert(status & kStatusRdy);
 		assert(status & kStatusDrq);
 
 		// Clear and acknowledge the IRQ.
 		auto cleared = _ioSpace.load(regs::inStatus);
-		HEL_CHECK(helAcknowledgeIrq(_irq.getHandle(), 0, 0));
+		HEL_CHECK(helAcknowledgeIrq(_irq.getHandle(), kHelAckAcknowledge, 0));
 		assert(!(cleared & (kStatusErr | kStatusDf)));
 		assert(cleared & kStatusRdy);
 		assert(cleared & kStatusDrq);

drivers/kbd/src/main.cpp

@@ -275,7 +275,8 @@ void sendByte(uint8_t data) {
 	base.store(kbd_register::data, data);
 }
 
-void readDeviceData() {
+bool readDeviceData() {
+	bool avail = false;
 	size_t batch = 1;
 	uint8_t status;
 	while((status = base.load(kbd_register::command)) & 0x01) {
@@ -289,7 +290,11 @@ void readDeviceData() {
 		}else{
 			handleKeyboardData(data);
 		}
+
+		avail = true;
 	}
+
+	return avail;
 }
 
 COFIBER_ROUTINE(cofiber::no_future, handleKbdIrqs(), ([=] {	
@@ -306,7 +311,8 @@ COFIBER_ROUTINE(cofiber::no_future, handleKbdIrqs(), ([=] {
 		readDeviceData();
 
 		// TODO: Only ack if the IRQ was from the PS/2 controller.
-		HEL_CHECK(helAcknowledgeIrq(kbdIrq.getHandle(), 0, sequence));
+		//HEL_CHECK(helAcknowledgeIrq(kbdIrq.getHandle(), kHelAckAcknowledge, 0));
+		HEL_CHECK(helAcknowledgeIrq(mouseIrq.getHandle(), kHelAckNack, sequence));
 	}
 }))
 
@@ -324,7 +330,7 @@ COFIBER_ROUTINE(cofiber::no_future, handleMouseIrqs(), ([=] {
 		readDeviceData();
 
 		// TODO: Only ack if the IRQ was from the PS/2 controller.
-		HEL_CHECK(helAcknowledgeIrq(mouseIrq.getHandle(), 0, sequence));
+		HEL_CHECK(helAcknowledgeIrq(mouseIrq.getHandle(), kHelAckAcknowledge, 0));
 	}
 }))
 

drivers/usb/hcds/ehci/src/main.cpp

@@ -400,6 +400,7 @@ COFIBER_ROUTINE(cofiber::no_future, Controller::handleIrqs(), ([=] {
 			 	&& !(status & usbsts::portChange)) {
 			if(logIrqs)
 				std::cout << "ehci: IRQ is not from this controller" << std::endl;
+			HEL_CHECK(helAcknowledgeIrq(_irq.getHandle(), kHelAckNack, sequence));
 			continue;
 		}
 
@@ -409,7 +410,7 @@ COFIBER_ROUTINE(cofiber::no_future, Controller::handleIrqs(), ([=] {
 				usbsts::transactionIrq(status & usbsts::transactionIrq)
 				| usbsts::errorIrq(status & usbsts::errorIrq)
 				| usbsts::portChange(status & usbsts::portChange));
-		HEL_CHECK(helAcknowledgeIrq(_irq.getHandle(), 0, 0));
+		HEL_CHECK(helAcknowledgeIrq(_irq.getHandle(), kHelAckAcknowledge, 0));
 
 		if((status & usbsts::transactionIrq)
 				|| (status & usbsts::errorIrq)) {

drivers/usb/hcds/uhci/src/main.cpp

@@ -465,14 +465,16 @@ COFIBER_ROUTINE(cofiber::no_future, Controller::_handleIrqs(), ([=] {
 		auto stat = _base.load(op_regs::status);
 		assert(!(stat & status::hostProcessError));
 		assert(!(stat & status::hostSystemError));
-		if(!(stat & status::transactionIrq) && !(stat & status::errorIrq))
+		if(!(stat & status::transactionIrq) && !(stat & status::errorIrq)) {
+			HEL_CHECK(helAcknowledgeIrq(_irq.getHandle(), kHelAckNack, sequence));
 			continue;
+		}
 
 		if(stat & status::errorIrq)
 			printf("uhci: Error interrupt\n");
 		_base.store(op_regs::status, status::transactionIrq(stat & status::transactionIrq) 
 				| status::errorIrq(stat & status::errorIrq));
-		HEL_CHECK(helAcknowledgeIrq(_irq.getHandle(), 0, sequence));
+		HEL_CHECK(helAcknowledgeIrq(_irq.getHandle(), kHelAckAcknowledge, 0));
 
 		//printf("uhci: Processing transfers.\n");
 		_progressSchedule();

hel/include/hel.h

@@ -343,6 +343,8 @@ enum HelIrqFlags {
 };
 
 enum HelAckFlags {
+	kHelAckAcknowledge = 2,
+	kHelAckNack = 3,
 	kHelAckKick = 1
 };
 

thor/kernel/src/arch/x86/hpet.cpp

@@ -67,6 +67,9 @@ struct HpetDevice : IrqSink {
 	static constexpr bool logIrqs = false;
 
 public:
+	HpetDevice()
+	: IrqSink{frigg::String<KernelAlloc>{*kernelAlloc, "hpet-irq"}} { }
+
 	void installTimer(PrecisionTimerNode *timer) {
 		auto irq_lock = frigg::guard(&irqMutex());
 		auto lock = frigg::guard(&_mutex);
@@ -83,9 +86,7 @@ struct HpetDevice : IrqSink {
 		_progress();
 	}
 
-	IrqStatus raise(uint64_t sequence) override {
-		(void)sequence;
-
+	IrqStatus raise() override {
 		if(logIrqs)
 			frigg::infoLogger() << "hpet: Irq was raised." << frigg::endLog;
 		auto irq_lock = frigg::guard(&irqMutex());
@@ -97,7 +98,7 @@ struct HpetDevice : IrqSink {
 		// For level-triggered mode we need to inspect the ISR.
 		if(logIrqs)
 			frigg::infoLogger() << "hpet: Handler completed." << frigg::endLog;
-		return irq_status::handled;
+		return IrqStatus::acked;
 	}
 
 private:
@@ -191,7 +192,7 @@ void setupHpet(PhysicalAddr address) {
 		hpetBase.store(genConfig, enableCounter(true));
 	}
 
-	attachIrq(getGlobalSystemIrq(2), hpetDevice.get());
+	IrqPin::attachSink(getGlobalSystemIrq(2), hpetDevice.get());
 
 	// Program HPET timer 0 in one-shot mode.
 	if(global_caps & supportsLegacyIrqs) {

thor/kernel/src/generic/hel.cpp

@@ -1761,8 +1761,9 @@ HelError helAccessIrq(int number, HelHandle *handle) {
 	auto this_thread = getCurrentThread();
 	auto this_universe = this_thread->getUniverse();
 
-	auto irq = frigg::makeShared<IrqObject>(*kernelAlloc);
-	attachIrq(getGlobalSystemIrq(number), irq.get());
+	auto irq = frigg::makeShared<IrqObject>(*kernelAlloc,
+			frigg::String<KernelAlloc>{*kernelAlloc, "generic-irq-object"});
+	IrqPin::attachSink(getGlobalSystemIrq(number), irq.get());
 
 	{
 		auto irq_lock = frigg::guard(&irqMutex());
@@ -1775,11 +1776,21 @@ HelError helAccessIrq(int number, HelHandle *handle) {
 	return kHelErrNone;
 }
 HelError helAcknowledgeIrq(HelHandle handle, uint32_t flags, uint64_t sequence) {
-	assert(!(flags & ~(kHelAckKick)));
+	assert(!(flags & ~(kHelAckAcknowledge | kHelAckNack | kHelAckKick)));
 
 	auto this_thread = getCurrentThread();
 	auto this_universe = this_thread->getUniverse();
 
+	auto mode = flags & (kHelAckAcknowledge | kHelAckNack | kHelAckKick);
+	if(mode == kHelAckAcknowledge || mode == kHelAckKick) {
+		if(sequence)
+			return kHelErrIllegalArgs;
+	}else if(mode == kHelAckNack) {
+		// Nothing to check here.
+	}else{
+		return kHelErrIllegalArgs;
+	}
+
 	frigg::SharedPtr<IrqObject> irq;
 	{
 		auto irq_lock = frigg::guard(&irqMutex());
@@ -1793,11 +1804,13 @@ HelError helAcknowledgeIrq(HelHandle handle, uint32_t flags, uint64_t sequence)
 		irq = irq_wrapper->get<IrqDescriptor>().irq;
 	}
 
-	if(flags & kHelAckKick) {
-		irq->acknowledge();
+	if(mode == kHelAckAcknowledge) {
+		IrqPin::ackSink(irq.get());
+	}else if(mode == kHelAckNack) {
+		IrqPin::nackSink(irq.get(), sequence);
 	}else{
-		assert(!flags);
-		irq->acknowledge();
+ 		assert(mode == kHelAckKick);
+		IrqPin::kickSink(irq.get());
 	}
 
 	return kHelErrNone;