Merge pull request #9 from bunnei/master

Add initial kernel HLE, includes thread creation and context switching

6 files changed, 867 insertions, 0 deletions

diff --git a/src/core/hle/kernel/kernel.cpp b/src/core/hle/kernel/kernel.cpp
new file mode 100644
index 000000000..de80de893
--- /dev/null
+++ b/src/core/hle/kernel/kernel.cpp
@@ -0,0 +1,158 @@
+// Copyright 2014 Citra Emulator Project / PPSSPP Project
+// Licensed under GPLv2
+// Refer to the license.txt file included.  
+
+#pragma once
+
+#include <string.h>
+
+#include "common/common.h"
+
+#include "core/core.h"
+#include "core/hle/kernel/kernel.h"
+#include "core/hle/kernel/thread.h"
+
+namespace Kernel {
+
+ObjectPool g_object_pool;
+
+ObjectPool::ObjectPool() {
+    memset(occupied, 0, sizeof(bool) * MAX_COUNT);
+    next_id = INITIAL_NEXT_ID;
+}
+
+Handle ObjectPool::Create(Object* obj, int range_bottom, int range_top) {
+    if (range_top > MAX_COUNT) {
+        range_top = MAX_COUNT;
+    }
+    if (next_id >= range_bottom && next_id < range_top) {
+        range_bottom = next_id++;
+    }
+    for (int i = range_bottom; i < range_top; i++) {
+        if (!occupied[i]) {
+            occupied[i] = true;
+            pool[i] = obj;
+            pool[i]->handle = i + HANDLE_OFFSET;
+            return i + HANDLE_OFFSET;
+        }
+    }
+    ERROR_LOG(HLE, "Unable to allocate kernel object, too many objects slots in use.");
+    return 0;
+}
+
+bool ObjectPool::IsValid(Handle handle) {
+    int index = handle - HANDLE_OFFSET;
+    if (index < 0)
+        return false;
+    if (index >= MAX_COUNT)
+        return false;
+
+    return occupied[index];
+}
+
+void ObjectPool::Clear() {
+    for (int i = 0; i < MAX_COUNT; i++) {
+        //brutally clear everything, no validation
+        if (occupied[i])
+            delete pool[i];
+        occupied[i] = false;
+    }
+    memset(pool, 0, sizeof(Object*)*MAX_COUNT);
+    next_id = INITIAL_NEXT_ID;
+}
+
+Object* &ObjectPool::operator [](Handle handle)
+{
+    _dbg_assert_msg_(KERNEL, IsValid(handle), "GRABBING UNALLOCED KERNEL OBJ");
+    return pool[handle - HANDLE_OFFSET];
+}
+
+void ObjectPool::List() {
+    for (int i = 0; i < MAX_COUNT; i++) {
+        if (occupied[i]) {
+            if (pool[i]) {
+                INFO_LOG(KERNEL, "KO %i: %s \"%s\"", i + HANDLE_OFFSET, pool[i]->GetTypeName(), 
+                    pool[i]->GetName());
+            }
+        }
+    }
+}
+
+int ObjectPool::GetCount() {
+    int count = 0;
+    for (int i = 0; i < MAX_COUNT; i++) {
+        if (occupied[i])
+            count++;
+    }
+    return count;
+}
+
+Object* ObjectPool::CreateByIDType(int type) {
+    // Used for save states.  This is ugly, but what other way is there?
+    switch (type) {
+    //case SCE_KERNEL_TMID_Alarm:
+    //    return __KernelAlarmObject();
+    //case SCE_KERNEL_TMID_EventFlag:
+    //    return __KernelEventFlagObject();
+    //case SCE_KERNEL_TMID_Mbox:
+    //    return __KernelMbxObject();
+    //case SCE_KERNEL_TMID_Fpl:
+    //    return __KernelMemoryFPLObject();
+    //case SCE_KERNEL_TMID_Vpl:
+    //    return __KernelMemoryVPLObject();
+    //case PPSSPP_KERNEL_TMID_PMB:
+    //    return __KernelMemoryPMBObject();
+    //case PPSSPP_KERNEL_TMID_Module:
+    //    return __KernelModuleObject();
+    //case SCE_KERNEL_TMID_Mpipe:
+    //    return __KernelMsgPipeObject();
+    //case SCE_KERNEL_TMID_Mutex:
+    //    return __KernelMutexObject();
+    //case SCE_KERNEL_TMID_LwMutex:
+    //    return __KernelLwMutexObject();
+    //case SCE_KERNEL_TMID_Semaphore:
+    //    return __KernelSemaphoreObject();
+    //case SCE_KERNEL_TMID_Callback:
+    //    return __KernelCallbackObject();
+    //case SCE_KERNEL_TMID_Thread:
+    //    return __KernelThreadObject();
+    //case SCE_KERNEL_TMID_VTimer:
+    //    return __KernelVTimerObject();
+    //case SCE_KERNEL_TMID_Tlspl:
+    //    return __KernelTlsplObject();
+    //case PPSSPP_KERNEL_TMID_File:
+    //    return __KernelFileNodeObject();
+    //case PPSSPP_KERNEL_TMID_DirList:
+    //    return __KernelDirListingObject();
+
+    default:
+        ERROR_LOG(COMMON, "Unable to load state: could not find object type %d.", type);
+        return NULL;
+    }
+}
+
+void Init() {
+    Kernel::ThreadingInit();
+}
+
+void Shutdown() {
+    Kernel::ThreadingShutdown();
+}
+
+/**
+ * Loads executable stored at specified address
+ * @entry_point Entry point in memory of loaded executable
+ * @return True on success, otherwise false
+ */
+bool LoadExec(u32 entry_point) {
+    Init();
+    
+    Core::g_app_core->SetPC(entry_point);
+
+    // 0x30 is the typical main thread priority I've seen used so far
+    Handle thread = Kernel::SetupMainThread(0x30);
+
+    return true;
+}
+
+} // namespace
diff --git a/src/core/hle/kernel/kernel.h b/src/core/hle/kernel/kernel.h
new file mode 100644
index 000000000..7cd79c2c4
--- /dev/null
+++ b/src/core/hle/kernel/kernel.h
@@ -0,0 +1,154 @@
+// Copyright 2014 Citra Emulator Project / PPSSPP Project
+// Licensed under GPLv2
+// Refer to the license.txt file included.  
+
+#pragma once
+
+#include "common/common.h"
+
+typedef u32 Handle;
+typedef s32 Result;
+
+namespace Kernel {
+
+enum class HandleType : u32 {
+    Unknown         = 0,
+    Port            = 1,
+    Service         = 2,
+    Event           = 3,
+    Mutex           = 4,
+    SharedMemory    = 5,
+    Redirection     = 6,
+    Thread          = 7,
+    Process         = 8,
+    Arbiter         = 9,
+    File            = 10,
+    Semaphore       = 11,
+};
+    
+enum {
+    MAX_NAME_LENGTH     = 0x100,
+    DEFAULT_STACK_SIZE  = 0x4000,
+};
+
+class ObjectPool;
+
+class Object : NonCopyable {
+    friend class ObjectPool;
+    u32 handle;
+public:
+    virtual ~Object() {}
+    Handle GetHandle() const { return handle; }
+    virtual const char *GetTypeName() { return "[BAD KERNEL OBJECT TYPE]"; }
+    virtual const char *GetName() { return "[UNKNOWN KERNEL OBJECT]"; }
+    virtual Kernel::HandleType GetHandleType() const = 0;
+};
+
+class ObjectPool : NonCopyable {
+public:
+    ObjectPool();
+    ~ObjectPool() {}
+
+    // Allocates a handle within the range and inserts the object into the map.
+    Handle Create(Object* obj, int range_bottom=INITIAL_NEXT_ID, int range_top=0x7FFFFFFF);
+
+    static Object* CreateByIDType(int type);
+
+    template <class T>
+    u32 Destroy(Handle handle) {
+        u32 error;
+        if (Get<T>(handle, error)) {
+            occupied[handle - HANDLE_OFFSET] = false;
+            delete pool[handle - HANDLE_OFFSET];
+        }
+        return error;
+    };
+
+    bool IsValid(Handle handle);
+
+    template <class T>
+    T* Get(Handle handle, u32& outError) {
+        if (handle < HANDLE_OFFSET || handle >= HANDLE_OFFSET + MAX_COUNT || !occupied[handle - HANDLE_OFFSET]) {
+            // Tekken 6 spams 0x80020001 gets wrong with no ill effects, also on the real PSP
+            if (handle != 0 && (u32)handle != 0x80020001) {
+                WARN_LOG(KERNEL, "Kernel: Bad object handle %i (%08x)", handle, handle);
+            }
+            outError = 0;//T::GetMissingErrorCode();
+            return 0;
+        } else {
+            // Previously we had a dynamic_cast here, but since RTTI was disabled traditionally,
+            // it just acted as a static case and everything worked. This means that we will never
+            // see the Wrong type object error below, but we'll just have to live with that danger.
+            T* t = static_cast<T*>(pool[handle - HANDLE_OFFSET]);
+            if (t == 0 || t->GetHandleType() != T::GetStaticHandleType()) {
+                WARN_LOG(KERNEL, "Kernel: Wrong object type for %i (%08x)", handle, handle);
+                outError = 0;//T::GetMissingErrorCode();
+                return 0;
+            }
+            outError = 0;//SCE_KERNEL_ERROR_OK;
+            return t;
+        }
+    }
+
+    // ONLY use this when you know the handle is valid.
+    template <class T>
+    T *GetFast(Handle handle) {
+        const Handle realHandle = handle - HANDLE_OFFSET;
+        _dbg_assert_(KERNEL, realHandle >= 0 && realHandle < MAX_COUNT && occupied[realHandle]);
+        return static_cast<T*>(pool[realHandle]);
+    }
+
+    template <class T, typename ArgT>
+    void Iterate(bool func(T*, ArgT), ArgT arg) {
+        int type = T::GetStaticIDType();
+        for (int i = 0; i < MAX_COUNT; i++)
+        {
+            if (!occupied[i])
+                continue;
+            T* t = static_cast<T*>(pool[i]);
+            if (t->GetIDType() == type) {
+                if (!func(t, arg))
+                    break;
+            }
+        }
+    }
+
+    bool GetIDType(Handle handle, HandleType* type) const {
+        if ((handle < HANDLE_OFFSET) || (handle >= HANDLE_OFFSET + MAX_COUNT) || 
+            !occupied[handle - HANDLE_OFFSET]) {
+            ERROR_LOG(KERNEL, "Kernel: Bad object handle %i (%08x)", handle, handle);
+            return false;
+        }
+        Object* t = pool[handle - HANDLE_OFFSET];
+        *type = t->GetHandleType();
+        return true;
+    }
+
+    Object* &operator [](Handle handle);
+    void List();
+    void Clear();
+    int GetCount();
+
+private:
+    
+    enum {
+        MAX_COUNT       = 0x1000,
+        HANDLE_OFFSET   = 0x100,
+        INITIAL_NEXT_ID = 0x10,
+    };
+
+    Object* pool[MAX_COUNT];
+    bool    occupied[MAX_COUNT];
+    int     next_id;
+};
+
+extern ObjectPool g_object_pool;
+
+/**
+ * Loads executable stored at specified address
+ * @entry_point Entry point in memory of loaded executable
+ * @return True on success, otherwise false
+ */
+bool LoadExec(u32 entry_point);
+
+} // namespace
diff --git a/src/core/hle/kernel/mutex.cpp b/src/core/hle/kernel/mutex.cpp
new file mode 100644
index 000000000..019efbc78
--- /dev/null
+++ b/src/core/hle/kernel/mutex.cpp
@@ -0,0 +1,132 @@
+// Copyright 2014 Citra Emulator Project
+// Licensed under GPLv2
+// Refer to the license.txt file included.  
+
+#include <map>
+#include <vector>
+
+#include "common/common.h"
+
+#include "core/hle/kernel/kernel.h"
+#include "core/hle/kernel/thread.h"
+
+namespace Kernel {
+
+class Mutex : public Object {
+public:
+    const char* GetTypeName() { return "Mutex"; }
+
+    static Kernel::HandleType GetStaticHandleType() {  return Kernel::HandleType::Mutex; }
+    Kernel::HandleType GetHandleType() const { return Kernel::HandleType::Mutex; }
+
+    bool initial_locked;                        ///< Initial lock state when mutex was created
+    bool locked;                                ///< Current locked state
+    Handle lock_thread;                         ///< Handle to thread that currently has mutex
+    std::vector<Handle> waiting_threads;        ///< Threads that are waiting for the mutex
+};
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+
+typedef std::multimap<Handle, Handle> MutexMap;
+static MutexMap g_mutex_held_locks;
+
+void MutexAcquireLock(Mutex* mutex, Handle thread) {
+    g_mutex_held_locks.insert(std::make_pair(thread, mutex->GetHandle()));
+    mutex->lock_thread = thread;
+}
+
+void MutexAcquireLock(Mutex* mutex) {
+    Handle thread = GetCurrentThreadHandle();
+    MutexAcquireLock(mutex, thread);
+}
+
+void MutexEraseLock(Mutex* mutex) {
+    Handle handle = mutex->GetHandle();
+    auto locked = g_mutex_held_locks.equal_range(mutex->lock_thread);
+    for (MutexMap::iterator iter = locked.first; iter != locked.second; ++iter) {
+        if ((*iter).second == handle) {
+            g_mutex_held_locks.erase(iter);
+            break;
+        }
+    }
+    mutex->lock_thread = -1;
+}
+
+bool LockMutex(Mutex* mutex) {
+    // Mutex alread locked?
+    if (mutex->locked) {
+        return false;
+    }
+    MutexAcquireLock(mutex);
+    return true;
+}
+
+bool ReleaseMutexForThread(Mutex* mutex, Handle thread) {
+    MutexAcquireLock(mutex, thread);
+    Kernel::ResumeThreadFromWait(thread);
+    return true;
+}
+
+bool ReleaseMutex(Mutex* mutex) {
+    MutexEraseLock(mutex);
+    bool woke_threads = false;
+    auto iter = mutex->waiting_threads.begin();
+
+    // Find the next waiting thread for the mutex...
+    while (!woke_threads && !mutex->waiting_threads.empty()) {
+        woke_threads |= ReleaseMutexForThread(mutex, *iter);
+        mutex->waiting_threads.erase(iter);
+    }
+    // Reset mutex lock thread handle, nothing is waiting
+    if (!woke_threads) {
+        mutex->locked = false;
+        mutex->lock_thread = -1;
+    }
+    return woke_threads;
+}
+
+/**
+ * Releases a mutex
+ * @param handle Handle to mutex to release
+ */
+Result ReleaseMutex(Handle handle) {
+    Mutex* mutex = Kernel::g_object_pool.GetFast<Mutex>(handle);
+    if (!ReleaseMutex(mutex)) {
+        return -1;
+    }
+    return 0;
+}
+
+/**
+ * Creates a mutex
+ * @param handle Reference to handle for the newly created mutex
+ * @param initial_locked Specifies if the mutex should be locked initially
+ */
+Mutex* CreateMutex(Handle& handle, bool initial_locked) {
+    Mutex* mutex = new Mutex;
+    handle = Kernel::g_object_pool.Create(mutex);
+
+    mutex->locked = mutex->initial_locked = initial_locked;
+
+    // Acquire mutex with current thread if initialized as locked...
+    if (mutex->locked) {
+        MutexAcquireLock(mutex);
+
+    // Otherwise, reset lock thread handle
+    } else {
+        mutex->lock_thread = -1;
+    }
+    return mutex;
+}
+
+/**
+ * Creates a mutex
+ * @param initial_locked Specifies if the mutex should be locked initially
+ */
+Handle CreateMutex(bool initial_locked) {
+    Handle handle;
+    Mutex* mutex = CreateMutex(handle, initial_locked);
+    return handle;
+}
+
+} // namespace
diff --git a/src/core/hle/kernel/mutex.h b/src/core/hle/kernel/mutex.h
new file mode 100644
index 000000000..871e2e562
--- /dev/null
+++ b/src/core/hle/kernel/mutex.h
@@ -0,0 +1,26 @@
+// Copyright 2014 Citra Emulator Project
+// Licensed under GPLv2
+// Refer to the license.txt file included.  
+
+#pragma once
+
+#include "common/common_types.h"
+
+#include "core/hle/kernel/kernel.h"
+
+namespace Kernel {
+
+/**
+ * Releases a mutex
+ * @param handle Handle to mutex to release
+ */
+Result ReleaseMutex(Handle handle);
+
+/**
+ * Creates a mutex
+ * @param handle Reference to handle for the newly created mutex
+ * @param initial_locked Specifies if the mutex should be locked initially
+ */
+Handle CreateMutex(bool initial_locked);
+
+} // namespace
diff --git a/src/core/hle/kernel/thread.cpp b/src/core/hle/kernel/thread.cpp
new file mode 100644
index 000000000..bf4c8353c
--- /dev/null
+++ b/src/core/hle/kernel/thread.cpp
@@ -0,0 +1,323 @@
+// Copyright 2014 Citra Emulator Project / PPSSPP Project
+// Licensed under GPLv2
+// Refer to the license.txt file included.  
+
+#include <stdio.h>
+
+#include <list>
+#include <vector>
+#include <map>
+#include <string>
+
+#include "common/common.h"
+#include "common/thread_queue_list.h"
+
+#include "core/core.h"
+#include "core/mem_map.h"
+#include "core/hle/hle.h"
+#include "core/hle/svc.h"
+#include "core/hle/kernel/kernel.h"
+#include "core/hle/kernel/thread.h"
+
+namespace Kernel {
+
+class Thread : public Kernel::Object {
+public:
+
+    const char* GetName() { return name; }
+    const char* GetTypeName() { return "Thread"; }
+
+    static Kernel::HandleType GetStaticHandleType() {  return Kernel::HandleType::Thread; }
+    Kernel::HandleType GetHandleType() const { return Kernel::HandleType::Thread; }
+
+    inline bool IsRunning() const { return (status & THREADSTATUS_RUNNING) != 0; }
+    inline bool IsStopped() const { return (status & THREADSTATUS_DORMANT) != 0; }
+    inline bool IsReady() const { return (status & THREADSTATUS_READY) != 0; }
+    inline bool IsWaiting() const { return (status & THREADSTATUS_WAIT) != 0; }
+    inline bool IsSuspended() const { return (status & THREADSTATUS_SUSPEND) != 0; }
+
+    ThreadContext context;
+
+    u32 status;
+    u32 entry_point;
+    u32 stack_top;
+    u32 stack_size;
+
+    s32 initial_priority;
+    s32 current_priority;
+
+    s32 processor_id;
+
+    WaitType wait_type;
+
+    char name[Kernel::MAX_NAME_LENGTH + 1];
+};
+
+// Lists all thread ids that aren't deleted/etc.
+std::vector<Handle> g_thread_queue;
+
+// Lists only ready thread ids.
+Common::ThreadQueueList<Handle> g_thread_ready_queue;
+
+Handle g_current_thread_handle;
+Thread* g_current_thread;
+
+
+/// Gets the current thread
+inline Thread* GetCurrentThread() {
+    return g_current_thread;
+}
+
+/// Gets the current thread handle
+Handle GetCurrentThreadHandle() {
+    return GetCurrentThread()->GetHandle();
+}
+
+/// Sets the current thread
+inline void SetCurrentThread(Thread* t) {
+    g_current_thread = t;
+    g_current_thread_handle = t->GetHandle();
+}
+
+/// Saves the current CPU context
+void SaveContext(ThreadContext& ctx) {
+    Core::g_app_core->SaveContext(ctx);
+}
+
+/// Loads a CPU context
+void LoadContext(ThreadContext& ctx) {
+    Core::g_app_core->LoadContext(ctx);
+}
+
+/// Resets a thread
+void ResetThread(Thread* t, u32 arg, s32 lowest_priority) {
+    memset(&t->context, 0, sizeof(ThreadContext));
+
+    t->context.cpu_registers[0] = arg;
+    t->context.pc = t->entry_point;
+    t->context.sp = t->stack_top;
+    t->context.cpsr = 0x1F; // Usermode
+    
+    if (t->current_priority < lowest_priority) {
+        t->current_priority = t->initial_priority;
+    }
+        
+    t->wait_type = WAITTYPE_NONE;
+}
+
+/// Change a thread to "ready" state
+void ChangeReadyState(Thread* t, bool ready) {
+    Handle handle = t->GetHandle();
+    if (t->IsReady()) {
+        if (!ready) {
+            g_thread_ready_queue.remove(t->current_priority, handle);
+        }
+    }  else if (ready) {
+        if (t->IsRunning()) {
+            g_thread_ready_queue.push_front(t->current_priority, handle);
+        } else {
+            g_thread_ready_queue.push_back(t->current_priority, handle);
+        }
+        t->status = THREADSTATUS_READY;
+    }
+}
+
+/// Changes a threads state
+void ChangeThreadState(Thread* t, ThreadStatus new_status) {
+    if (!t || t->status == new_status) {
+        return;
+    }
+    ChangeReadyState(t, (new_status & THREADSTATUS_READY) != 0);
+    t->status = new_status;
+    
+    if (new_status == THREADSTATUS_WAIT) {
+        if (t->wait_type == WAITTYPE_NONE) {
+            printf("ERROR: Waittype none not allowed here\n");
+        }
+    }
+}
+
+/// Calls a thread by marking it as "ready" (note: will not actually execute until current thread yields)
+void CallThread(Thread* t) {
+    // Stop waiting
+    if (t->wait_type != WAITTYPE_NONE) {
+        t->wait_type = WAITTYPE_NONE;
+    }
+    ChangeThreadState(t, THREADSTATUS_READY);
+}
+
+/// Switches CPU context to that of the specified thread
+void SwitchContext(Thread* t) {
+    Thread* cur = GetCurrentThread();
+    
+    // Save context for current thread
+    if (cur) {
+        SaveContext(cur->context);
+        
+        if (cur->IsRunning()) {
+            ChangeReadyState(cur, true);
+        }
+    }
+    // Load context of new thread
+    if (t) {
+        SetCurrentThread(t);
+        ChangeReadyState(t, false);
+        t->status = (t->status | THREADSTATUS_RUNNING) & ~THREADSTATUS_READY;
+        t->wait_type = WAITTYPE_NONE;
+        LoadContext(t->context);
+    } else {
+        SetCurrentThread(NULL);
+    }
+}
+
+/// Gets the next thread that is ready to be run by priority
+Thread* NextThread() {
+    Handle next;
+    Thread* cur = GetCurrentThread();
+    
+    if (cur && cur->IsRunning()) {
+        next = g_thread_ready_queue.pop_first_better(cur->current_priority);
+    } else  {
+        next = g_thread_ready_queue.pop_first();
+    }
+    if (next == 0) {
+        return NULL;
+    }
+    return Kernel::g_object_pool.GetFast<Thread>(next);
+}
+
+/// Puts the current thread in the wait state for the given type
+void WaitCurrentThread(WaitType wait_type) {
+    Thread* t = GetCurrentThread();
+    t->wait_type = wait_type;
+    ChangeThreadState(t, ThreadStatus(THREADSTATUS_WAIT | (t->status & THREADSTATUS_SUSPEND)));
+}
+
+/// Resumes a thread from waiting by marking it as "ready"
+void ResumeThreadFromWait(Handle handle) {
+    u32 error;
+    Thread* t = Kernel::g_object_pool.Get<Thread>(handle, error);
+    if (t) {
+        t->status &= ~THREADSTATUS_WAIT;
+        if (!(t->status & (THREADSTATUS_WAITSUSPEND | THREADSTATUS_DORMANT | THREADSTATUS_DEAD))) {
+            ChangeReadyState(t, true);
+        }
+    }
+}
+
+/// Creates a new thread
+Thread* CreateThread(Handle& handle, const char* name, u32 entry_point, s32 priority,
+    s32 processor_id, u32 stack_top, int stack_size) {
+
+    _assert_msg_(KERNEL, (priority >= THREADPRIO_HIGHEST && priority <= THREADPRIO_LOWEST), 
+        "CreateThread priority=%d, outside of allowable range!", priority)
+
+    Thread* t = new Thread;
+    
+    handle = Kernel::g_object_pool.Create(t);
+    
+    g_thread_queue.push_back(handle);
+    g_thread_ready_queue.prepare(priority);
+    
+    t->status = THREADSTATUS_DORMANT;
+    t->entry_point = entry_point;
+    t->stack_top = stack_top;
+    t->stack_size = stack_size;
+    t->initial_priority = t->current_priority = priority;
+    t->processor_id = processor_id;
+    t->wait_type = WAITTYPE_NONE;
+    
+    strncpy(t->name, name, Kernel::MAX_NAME_LENGTH);
+    t->name[Kernel::MAX_NAME_LENGTH] = '\0';
+    
+    return t;
+}
+
+/// Creates a new thread - wrapper for external user
+Handle CreateThread(const char* name, u32 entry_point, s32 priority, u32 arg, s32 processor_id,
+    u32 stack_top, int stack_size) {
+    if (name == NULL) {
+        ERROR_LOG(KERNEL, "CreateThread(): NULL name");
+        return -1;
+    }
+    if ((u32)stack_size < 0x200) {
+        ERROR_LOG(KERNEL, "CreateThread(name=%s): invalid stack_size=0x%08X", name, 
+            stack_size);
+        return -1;
+    }
+    if (priority < THREADPRIO_HIGHEST || priority > THREADPRIO_LOWEST) {
+        s32 new_priority = CLAMP(priority, THREADPRIO_HIGHEST, THREADPRIO_LOWEST);
+        WARN_LOG(KERNEL, "CreateThread(name=%s): invalid priority=0x%08X, clamping to %08X",
+            name, priority, new_priority);
+        // TODO(bunnei): Clamping to a valid priority is not necessarily correct behavior... Confirm
+        // validity of this
+        priority = new_priority;
+    }
+    if (!Memory::GetPointer(entry_point)) {
+        ERROR_LOG(KERNEL, "CreateThread(name=%s): invalid entry %08x", name, entry_point);
+        return -1;
+    }
+    Handle handle;
+    Thread* t = CreateThread(handle, name, entry_point, priority, processor_id, stack_top, 
+        stack_size);
+
+    ResetThread(t, arg, 0);
+
+    HLE::EatCycles(32000);
+
+    // This won't schedule to the new thread, but it may to one woken from eating cycles.
+    // Technically, this should not eat all at once, and reschedule in the middle, but that's hard.
+    HLE::ReSchedule("thread created");
+
+    CallThread(t);
+    
+    return handle;
+}
+
+/// Sets up the primary application thread
+Handle SetupMainThread(s32 priority, int stack_size) {
+    Handle handle;
+    
+    // Initialize new "main" thread
+    Thread* t = CreateThread(handle, "main", Core::g_app_core->GetPC(), priority, 
+        THREADPROCESSORID_0, Memory::SCRATCHPAD_VADDR_END, stack_size);
+    
+    ResetThread(t, 0, 0);
+    
+    // If running another thread already, set it to "ready" state
+    Thread* cur = GetCurrentThread();
+    if (cur && cur->IsRunning()) {
+        ChangeReadyState(cur, true);
+    }
+    
+    // Run new "main" thread
+    SetCurrentThread(t);
+    t->status = THREADSTATUS_RUNNING;
+    LoadContext(t->context);
+
+    return handle;
+}
+
+/// Reschedules to the next available thread (call after current thread is suspended)
+void Reschedule() {
+    Thread* prev = GetCurrentThread();
+    Thread* next = NextThread();
+    if (next > 0) {
+        SwitchContext(next);
+
+        // Hack - automatically change previous thread (which would have been in "wait" state) to
+        // "ready" state, so that we can immediately resume to it when new thread yields. FixMe to
+        // actually wait for whatever event it is supposed to be waiting on.
+        ChangeReadyState(prev, true);
+    }
+}
+
+////////////////////////////////////////////////////////////////////////////////////////////////////
+
+void ThreadingInit() {
+}
+
+void ThreadingShutdown() {
+}
+
+} // namespace
diff --git a/src/core/hle/kernel/thread.h b/src/core/hle/kernel/thread.h
new file mode 100644
index 000000000..9628f165d
--- /dev/null
+++ b/src/core/hle/kernel/thread.h
@@ -0,0 +1,74 @@
+// Copyright 2014 Citra Emulator Project / PPSSPP Project
+// Licensed under GPLv2
+// Refer to the license.txt file included.  
+
+#pragma once
+
+#include "common/common_types.h"
+#include "core/hle/kernel/kernel.h"
+
+enum ThreadPriority {
+    THREADPRIO_HIGHEST      = 0,    ///< Highest thread priority
+    THREADPRIO_DEFAULT      = 16,   ///< Default thread priority for userland apps
+    THREADPRIO_LOW          = 31,   ///< Low range of thread priority for userland apps
+    THREADPRIO_LOWEST       = 63,   ///< Thread priority max checked by svcCreateThread
+};
+
+enum ThreadProcessorId {
+    THREADPROCESSORID_0     = 0xFFFFFFFE,   ///< Enables core appcode
+    THREADPROCESSORID_1     = 0xFFFFFFFD,   ///< Enables core syscore
+    THREADPROCESSORID_ALL   = 0xFFFFFFFC,   ///< Enables both cores
+};
+
+enum ThreadStatus {
+    THREADSTATUS_RUNNING        = 1,
+    THREADSTATUS_READY          = 2,
+    THREADSTATUS_WAIT           = 4,
+    THREADSTATUS_SUSPEND        = 8,
+    THREADSTATUS_DORMANT        = 16,
+    THREADSTATUS_DEAD           = 32,
+    THREADSTATUS_WAITSUSPEND    = THREADSTATUS_WAIT | THREADSTATUS_SUSPEND
+};
+
+enum WaitType {
+    WAITTYPE_NONE,
+    WAITTYPE_SLEEP,
+    WAITTYPE_SEMA,
+    WAITTYPE_EVENTFLAG,
+    WAITTYPE_THREADEND,
+    WAITTYPE_VBLANK,
+    WAITTYPE_MUTEX,
+    WAITTYPE_SYNCH,
+};
+
+namespace Kernel {
+
+/// Creates a new thread - wrapper for external user
+Handle CreateThread(const char* name, u32 entry_point, s32 priority, u32 arg, s32 processor_id,
+    u32 stack_top, int stack_size=Kernel::DEFAULT_STACK_SIZE);
+
+/// Sets up the primary application thread
+Handle SetupMainThread(s32 priority, int stack_size=Kernel::DEFAULT_STACK_SIZE);
+
+/// Reschedules to the next available thread (call after current thread is suspended)
+void Reschedule();
+
+/// Puts the current thread in the wait state for the given type
+void WaitCurrentThread(WaitType wait_type);
+
+/// Resumes a thread from waiting by marking it as "ready"
+void ResumeThreadFromWait(Handle handle);
+
+/// Gets the current thread handle
+Handle GetCurrentThreadHandle();
+
+/// Put current thread in a wait state - on WaitSynchronization
+void WaitThread_Synchronization();
+
+/// Initialize threading
+void ThreadingInit();
+
+/// Shutdown threading
+void ThreadingShutdown();
+
+} // namespace