Semaphores v0.1

include/kernel/kernel.hpp

@@ -48,6 +48,7 @@ class Kernel {
 
 public:
 	Handle makeMutex(bool locked = false); // Needs to be public to be accessible to the APT/DSP services
+	Handle makeSemaphore(u32 initialCount, u32 maximumCount); // Needs to be public to be accessible to the service manager port
 
 private:
 	void signalArbiter(u32 waitingAddress, s32 threadCount);

include/kernel/kernel_types.hpp

@@ -118,7 +118,7 @@ struct Thread {
     u32 waitingAddress;
 
     // The nanoseconds until a thread wakes up from being asleep or from timing out while waiting on an arbiter
-    s64 waitingNanoseconds;
+    u64 waitingNanoseconds;
     // The tick this thread went to sleep on
     u64 sleepTick;
     // For WaitSynchronization: A vector of objects this thread is waiting for
@@ -157,6 +157,13 @@ struct Mutex {
     Mutex(bool lock = false) : locked(lock) {}
 };
 
+struct Semaphore {
+    u32 initialCount;
+    u32 maximumCount;
+
+    Semaphore(u32 initialCount, u32 maximumCount) : initialCount(initialCount), maximumCount(maximumCount) {}
+};
+
 // Generic kernel object class
 struct KernelObject {
     Handle handle = 0; // A u32 the OS will use to identify objects

include/services/service_manager.hpp

@@ -1,6 +1,7 @@
 #pragma once
 #include <array>
-#include "helpers.hpp"
+#include <optional>
+#include "kernel_types.hpp"
 #include "logger.hpp"
 #include "memory.hpp"
 #include "services/apt.hpp"
@@ -15,11 +16,16 @@
 #include "services/ndm.hpp"
 #include "services/ptm.hpp"
 
+// More circular dependencies!!
 class Kernel;
 
 class ServiceManager {
 	std::array<u32, 16>& regs;
 	Memory& mem;
+	Kernel& kernel;
+
+	std::optional<Handle> notificationSemaphore;
+
 	MAKE_LOG_FUNCTION(log, srvLogger)
 
 	APTService apt;

src/core/kernel/events.cpp

@@ -73,7 +73,7 @@ void Kernel::waitSynchronization1() {
 	const auto object = getObject(handle);
 
 	if (object == nullptr) [[unlikely]] {
-		Helpers::panic("WaitSynchronization1: Bad event handle");
+		Helpers::panic("WaitSynchronization1: Bad event handle %X\n", handle);
 		regs[0] = SVCResult::BadHandle;
 		return;
 	}
@@ -104,7 +104,7 @@ void Kernel::waitSynchronizationN() {
 	s32 pointer = regs[5];
 	s64 ns = s64(ns1) | (s64(ns2) << 32);
 
-	logSVC("WaitSynchronizationN (handle pointer: %08X, count: %d)\n", handles, handleCount);
+	logSVC("WaitSynchronizationN (handle pointer: %08X, count: %d, timeout = %lld)\n", handles, handleCount, ns);
 	ThreadStatus newStatus = waitAll ? ThreadStatus::WaitSyncAll : ThreadStatus::WaitSync1;
 
 	auto& t = threads[currentThreadIndex];
@@ -118,7 +118,7 @@ void Kernel::waitSynchronizationN() {
 
 		auto object = getObject(handle);
 		if (object == nullptr) [[unlikely]] {
-			Helpers::panic("WaitSynchronizationN: Bad object handle");
+			Helpers::panic("WaitSynchronizationN: Bad object handle %X\n", handle);
 			regs[0] = SVCResult::BadHandle;
 			return;
 		}
@@ -131,5 +131,6 @@ void Kernel::waitSynchronizationN() {
 	regs[0] = SVCResult::Success;
 	t.status = newStatus;
 	t.waitingNanoseconds = ns;
+	t.sleepTick = cpu.getTicks();
 	switchToNextThread();
 }

src/core/kernel/threads.cpp

@@ -82,7 +82,8 @@ void Kernel::switchToNextThread() {
 	std::optional<int> newThreadIndex = getNextThread();
 	
 	if (!newThreadIndex.has_value()) {
-		Helpers::panic("Kernel tried to switch to the next thread but none found");
+		Helpers::warn("Kernel tried to switch to the next thread but none found. Switching to thread 0\n");
+		switchThread(0);
 	} else {
 		switchThread(newThreadIndex.value());
 	}
@@ -149,6 +150,13 @@ Handle Kernel::makeMutex(bool locked) {
 	return ret;
 }
 
+Handle Kernel::makeSemaphore(u32 initialCount, u32 maximumCount) {
+	Handle ret = makeObject(KernelObjectType::Semaphore);
+	objects[ret].data = new Semaphore(initialCount, maximumCount);
+
+	return ret;
+}
+
 void Kernel::sleepThreadOnArbiter(u32 waitingAddress) {
 	Thread& t = threads[currentThreadIndex];
 	t.status = ThreadStatus::WaitArbiter;

src/core/services/service_manager.cpp

@@ -1,8 +1,11 @@
 #include "services/service_manager.hpp"
+#include "kernel.hpp"
 
 ServiceManager::ServiceManager(std::array<u32, 16>& regs, Memory& mem, GPU& gpu, u32& currentPID, Kernel& kernel)
-	: regs(regs), mem(mem), apt(mem, kernel), cecd(mem), cfg(mem), dsp(mem), hid(mem), fs(mem, kernel), gsp_gpu(mem, gpu, currentPID),
-	gsp_lcd(mem), mic(mem), ndm(mem), ptm(mem) {}
+	: regs(regs), mem(mem), kernel(kernel), apt(mem, kernel), cecd(mem), cfg(mem), dsp(mem), hid(mem), 
+	fs(mem, kernel), gsp_gpu(mem, gpu, currentPID), gsp_lcd(mem), mic(mem), ndm(mem), ptm(mem) {}
+
+static constexpr int MAX_NOTIFICATION_COUNT = 16;
 
 void ServiceManager::reset() {
 	apt.reset();
@@ -16,6 +19,8 @@ void ServiceManager::reset() {
 	mic.reset();
 	ndm.reset();
 	ptm.reset();
+
+	notificationSemaphore = std::nullopt;
 }
 
 // Match IPC messages to a "srv:" command based on their header
@@ -109,12 +114,17 @@ void ServiceManager::getServiceHandle(u32 messagePointer) {
 }
 
 void ServiceManager::enableNotification(u32 messagePointer) {
-	log("srv::EnableNotification() (STUBBED)\n");
+	log("srv::EnableNotification()\n");
+
+	// Make a semaphore for notifications if none exists currently
+	if (!notificationSemaphore.has_value() || kernel.getObject(notificationSemaphore.value(), KernelObjectType::Semaphore) == nullptr) {
+		notificationSemaphore = kernel.makeSemaphore(0, MAX_NOTIFICATION_COUNT);
+	}
 
 	mem.write32(messagePointer + 4, Result::Success); // Result code
 	mem.write32(messagePointer + 8, 0); // Translation descriptor
-	// TODO: Unstub. Handle to semaphore signaled on process notification
-	mem.write32(messagePointer + 12, 0x69696979);
+	// Handle to semaphore signaled on process notification
+	mem.write32(messagePointer + 12, notificationSemaphore.value());
 }
 
 void ServiceManager::receiveNotification(u32 messagePointer) {