2 files changed, 44 insertions, 0 deletions

diff --git a/src/core/hle/kernel/thread.cpp b/src/core/hle/kernel/thread.cpp
index ab5a5559e..86bbf29d0 100644
--- a/src/core/hle/kernel/thread.cpp
+++ b/src/core/hle/kernel/thread.cpp
@@ -188,6 +188,43 @@ void ChangeThreadState(Thread* t, ThreadStatus new_status) {
     }
 }
 
+/// Arbitrate the highest priority thread that is waiting
+Handle ArbitrateHighestPriorityThread(u32 arbiter, u32 address) {
+    Handle highest_priority_thread = 0;
+    s32 priority = THREADPRIO_LOWEST;
+
+    // Iterate through threads, find highest priority thread that is waiting to be arbitrated...
+    for (const auto& handle : g_thread_queue) {
+
+        // TODO(bunnei): Verify arbiter address...
+        if (!VerifyWait(handle, WAITTYPE_ARB, arbiter))
+            continue;
+
+        Thread* thread = g_object_pool.GetFast<Thread>(handle);
+        if(thread->current_priority <= priority) {
+            highest_priority_thread = handle;
+            priority = thread->current_priority;
+        }
+    }
+    // If a thread was arbitrated, resume it
+    if (0 != highest_priority_thread)
+        ResumeThreadFromWait(highest_priority_thread);
+
+    return highest_priority_thread;
+}
+
+/// Arbitrate all threads currently waiting
+void ArbitrateAllThreads(u32 arbiter, u32 address) {
+    
+    // Iterate through threads, find highest priority thread that is waiting to be arbitrated...
+    for (const auto& handle : g_thread_queue) {
+
+        // TODO(bunnei): Verify arbiter address...
+        if (VerifyWait(handle, WAITTYPE_ARB, arbiter))
+            ResumeThreadFromWait(handle);
+    }
+}
+
 /// Calls a thread by marking it as "ready" (note: will not actually execute until current thread yields)
 void CallThread(Thread* t) {
     // Stop waiting
diff --git a/src/core/hle/kernel/thread.h b/src/core/hle/kernel/thread.h
index 04914ba90..f2bfdfa1a 100644
--- a/src/core/hle/kernel/thread.h
+++ b/src/core/hle/kernel/thread.h
@@ -39,6 +39,7 @@ enum WaitType {
     WAITTYPE_VBLANK,
     WAITTYPE_MUTEX,
     WAITTYPE_SYNCH,
+    WAITTYPE_ARB,
 };
 
 namespace Kernel {
@@ -59,6 +60,12 @@ void StopThread(Handle thread, const char* reason);
 /// Resumes a thread from waiting by marking it as "ready"
 void ResumeThreadFromWait(Handle handle);
 
+/// Arbitrate the highest priority thread that is waiting
+Handle ArbitrateHighestPriorityThread(u32 arbiter, u32 address);
+
+/// Arbitrate all threads currently waiting...
+void ArbitrateAllThreads(u32 arbiter, u32 address);
+
 /// Gets the current thread handle
 Handle GetCurrentThreadHandle();