diff --git a/trunk/bootrom/build/libraries/os/ARM11/Makefile b/trunk/bootrom/build/libraries/os/ARM11/Makefile
index bfadf58..0c8fac2 100644
--- a/trunk/bootrom/build/libraries/os/ARM11/Makefile
+++ b/trunk/bootrom/build/libraries/os/ARM11/Makefile
@@ -40,6 +40,7 @@ SRCS			= \
 				os_context.c \
 				os_cache.c \
 				os_printf.c \
+				os_mutex.c \
 
 TARGET_LIB		= libos$(BROM_LIBSUFFIX).a
 
diff --git a/trunk/bootrom/build/libraries/os/ARM9/Makefile b/trunk/bootrom/build/libraries/os/ARM9/Makefile
index 8612c4f..b04c8ba 100644
--- a/trunk/bootrom/build/libraries/os/ARM9/Makefile
+++ b/trunk/bootrom/build/libraries/os/ARM9/Makefile
@@ -40,6 +40,7 @@ SRCS			= \
 				os_interrupt.c \
 				os_exception.c \
 				os_thread.c \
+				os_mutex.c \
 				os_context.c \
 				os_cache.c \
 				os_printf.c \
diff --git a/trunk/bootrom/build/libraries/os/common/os_mutex.c b/trunk/bootrom/build/libraries/os/common/os_mutex.c
new file mode 100644
index 0000000..8f58f88
--- /dev/null
+++ b/trunk/bootrom/build/libraries/os/common/os_mutex.c
@@ -0,0 +1,703 @@
+/*---------------------------------------------------------------------------*
+  Project:  CtrBrom - libraries - OS
+  File:     os_mutex.c
+
+  Copyright 2009 Nintendo.  All rights reserved.
+
+  These coded instructions, statements, and computer programs contain
+  proprietary information of Nintendo of America Inc. and/or Nintendo
+  Company Ltd., and are protected by Federal copyright law.  They may
+  not be disclosed to third parties or copied or duplicated in any form,
+  in whole or in part, without the prior written consent of Nintendo.
+
+  $Date::            $
+  $Rev$
+  $Author$
+ *---------------------------------------------------------------------------*/
+#include <brom/types.h>
+#include <brom.h>
+
+void i_osUnlockMutexCore(OSMutex *mutex, u32 type);
+
+void    i_osEnqueueTail(OSThread *thread, OSMutex *mutex);
+void    i_osDequeueItem(OSThread *thread, OSMutex *mutex);
+OSMutex *i_osDequeueHead(OSThread *thread);
+
+/*---------------------------------------------------------------------------*
+  Name:         osInitMutex
+
+  Description:  initialize mutex
+
+  Arguments:    mutex       pointer to mutex structure
+                            to be initialized
+
+  Returns:      None
+ *---------------------------------------------------------------------------*/
+void osInitMutex(OSMutex *mutex)
+{
+    SDK_ASSERT(mutex);
+
+    osInitThreadQueue(&mutex->queue);
+    mutex->thread = NULL;
+    osSetMutexCount( mutex, 0 );
+    osSetMutexType( mutex, OS_MUTEX_TYPE_NONE );
+}
+
+/*---------------------------------------------------------------------------*
+  Name:         osLockMutex
+
+  Description:  lock mutex
+
+  Arguments:    mutex       pointer to mutex structure
+
+  Returns:      None
+ *---------------------------------------------------------------------------*/
+void osLockMutex(OSMutex *mutex)
+{
+    OSIntrMode e = osDisableInterrupts();
+    OSThread *currentThread = osGetCurrentThread();
+
+    while(1)
+    {
+        //---- try lock mutex
+        if ( osTryLockMutex(mutex) )
+        {
+            break;
+        }
+
+        currentThread->mutex = mutex;
+        osSleepThread(&mutex->queue);
+        currentThread->mutex = NULL;
+    }
+
+    (void)osRestoreInterrupts(e);
+}
+
+/*---------------------------------------------------------------------------*
+  Name:         osUnlockMutex
+
+  Description:  unlock mutex
+
+  Arguments:    mutex       pointer to mutex structure
+
+  Returns:      None
+ *---------------------------------------------------------------------------*/
+void osUnlockMutex(OSMutex *mutex)
+{
+    i_osUnlockMutexCore(mutex, OS_MUTEX_TYPE_STD);
+}
+
+/*---------------------------------------------------------------------------*
+  Name:         i_osUnlockAllMutex
+
+  Description:  unlocks all the mutexes locked by the thread
+
+  Arguments:    mutex       pointer to mutex structure
+
+  Returns:      None.
+ *---------------------------------------------------------------------------*/
+void i_osUnlockAllMutex(OSThread *thread)
+{
+    OSMutex *mutex;
+
+    SDK_ASSERT(thread);
+
+#ifndef SDK_THREAD_INFINITY
+    while (thread->mutexQueueHead)
+    {
+        mutex = i_osDequeueHead(thread);
+        SDK_ASSERT(mutex->thread == thread);
+
+        osSetMutexCount( mutex, 0 );
+        mutex->thread = NULL;
+        osSetMutexType( mutex, OS_MUTEX_TYPE_NONE );
+        osWakeupThread(&(mutex->queue));
+    }
+#else
+    while (thread->mutexQueue.head)
+    {
+        mutex = i_osRemoveMutexLinkFromQueue(&thread->mutexQueue);
+        SDK_ASSERT(mutex->thread == thread);
+
+        osSetMutexCount( mutex, 0 );
+        mutex->thread = NULL;
+        osSetMutexType( mutex, OS_MUTEX_TYPE_NONE );
+        osWakeupThread(&mutex->queue);
+    }
+#endif
+}
+
+/*---------------------------------------------------------------------------*
+  Name:         osTryLockMutex
+
+  Description:  try to lock mutex
+
+  Arguments:    mutex       pointer to mutex structure
+
+  Returns:      True if lock
+ *---------------------------------------------------------------------------*/
+BOOL osTryLockMutex(OSMutex *mutex)
+{
+    OSIntrMode saved = osDisableInterrupts();
+    OSThread *currentThread = osGetCurrentThread();
+    BOOL    locked;
+
+    SDK_ASSERT(mutex);
+
+    // ---- able to lock mutex
+    if (mutex->thread == NULL)
+    {
+        mutex->thread = currentThread;
+        osSetMutexType( mutex, OS_MUTEX_TYPE_STD );
+        osIncreaseMutexCount(mutex);
+        i_osEnqueueTail(currentThread, mutex);
+        locked = TRUE;
+    }
+    // ---- current thread is same with thread locking mutex
+    else if (mutex->thread == currentThread)
+    {
+        osIncreaseMutexCount(mutex);
+        locked = TRUE;
+    }
+    // ---- current thread is different from locking mutex
+    else
+    {
+        locked = FALSE;
+    }
+
+    (void)osRestoreInterrupts(saved);
+    return locked;
+}
+
+//================================================================================
+// Read / Write Lock
+//================================================================================
+/*---------------------------------------------------------------------------*
+  Name:         osLockMutexR
+
+  Description:  lock RW mutex as READ access
+
+  Arguments:    mutex       pointer to RW mutex structure
+
+  Returns:      None
+ *---------------------------------------------------------------------------*/
+void osLockMutexR(OSMutex *mutex)
+{
+    OSIntrMode e = osDisableInterrupts();
+    OSThread *currentThread = osGetCurrentThread();
+
+    while(1)
+    {
+        //---- try lock by READ
+        if ( osTryLockMutexR(mutex) )
+        {
+            break;
+        }
+
+        currentThread->mutex = mutex;
+        osSleepThread(&mutex->queue);
+        currentThread->mutex = NULL;
+    }
+
+    (void)osRestoreInterrupts(e);
+}
+
+/*---------------------------------------------------------------------------*
+  Name:         osLockMutexW
+
+  Description:  lock RW mutex as WRITE access
+
+  Arguments:    mutex       pointer to RW mutex structure
+
+  Returns:      None
+ *---------------------------------------------------------------------------*/
+void osLockMutexW(OSMutex *mutex)
+{
+    OSIntrMode e = osDisableInterrupts();
+    OSThread *currentThread = osGetCurrentThread();
+
+    while(1)
+    {
+        //---- try lock by WRITE
+        if ( osTryLockMutexW(mutex) )
+        {
+            break;
+        }
+
+        currentThread->mutex = mutex;
+        osSleepThread(&mutex->queue);
+        currentThread->mutex = NULL;
+    }
+
+    (void)osRestoreInterrupts(e);
+}
+
+/*---------------------------------------------------------------------------*
+  Name:         osTryLockMutexR
+
+  Description:  try to lock RW mutex as READ access
+
+  Arguments:    mutex       pointer to RW mutex structure
+
+  Returns:      TRUE if locked
+ *---------------------------------------------------------------------------*/
+BOOL osTryLockMutexR(OSMutex *mutex)
+{
+    OSIntrMode e = osDisableInterrupts();
+    BOOL locked = FALSE;
+    OSThread * currentThread = osGetCurrentThread();
+
+    switch( osGetMutexType(mutex) )
+    {
+    case OS_MUTEX_TYPE_NONE:
+        mutex->thread = currentThread;
+        osSetMutexType( mutex, OS_MUTEX_TYPE_R );
+        osSetMutexCount( mutex, 1 );
+        i_osEnqueueTail(currentThread, mutex);
+        locked = TRUE;
+        break;
+
+    case OS_MUTEX_TYPE_R:
+        osIncreaseMutexCount(mutex);
+        locked = TRUE;
+        break;
+
+    case OS_MUTEX_TYPE_W:
+    default:
+        break;
+    }
+
+    (void)osRestoreInterrupts(e);
+    return locked;
+}
+
+/*---------------------------------------------------------------------------*
+  Name:         osTryLockMutexW
+
+  Description:  try to lock RW mutex as WRITE access
+
+  Arguments:    mutex       pointer to RW mutex structure
+
+  Returns:      TRUE if locked
+ *---------------------------------------------------------------------------*/
+BOOL osTryLockMutexW(OSMutex *mutex)
+{
+    OSIntrMode e = osDisableInterrupts();
+    BOOL locked = FALSE;
+    OSThread * currentThread = osGetCurrentThread();
+
+    switch( osGetMutexType(mutex) )
+    {
+    case OS_MUTEX_TYPE_NONE:
+        mutex->thread = currentThread;
+        osSetMutexType( mutex, OS_MUTEX_TYPE_W );
+        osSetMutexCount( mutex, 1 );
+        i_osEnqueueTail(currentThread, mutex);
+        locked = TRUE;
+        break;
+
+    case OS_MUTEX_TYPE_W:
+        if ( mutex->thread == currentThread )
+        {
+            osIncreaseMutexCount(mutex);
+            locked = TRUE;
+        }
+        break;
+
+    case OS_MUTEX_TYPE_R:
+    default:
+        break;
+    }
+
+    (void)osRestoreInterrupts(e);
+    return locked;
+}
+
+/*---------------------------------------------------------------------------*
+  Name:         i_osUnlockMutexCore
+
+  Description:  core routine to unlock mutex
+
+  Arguments:    mutex       pointer to RW mutex structure
+                type        mutex type. if different from osGetMutexType(), error.
+                              OS_MUTEX_TYPE_STD
+                              OS_MUTEX_TYPE_R
+                              OS_MUTEX_TYPE_W
+                              OS_MUTEX_TYPE_NONE (no check)
+
+  Returns:      None
+ *---------------------------------------------------------------------------*/
+void i_osUnlockMutexCore(OSMutex *mutex, u32 type )
+{
+    OSIntrMode e = osDisableInterrupts();
+    OSThread *currentThread = osGetCurrentThread();
+    BOOL unlocked = FALSE;
+
+    SDK_ASSERT(mutex);
+
+    //---- check unlock type
+    if ( type != OS_MUTEX_TYPE_NONE && type != osGetMutexType(mutex) )
+    {
+        //osTPanic("Illegal unlock mutex\n");
+        osTWarning("Illegal unlock mutex");
+        (void)osRestoreInterrupts(e);
+        return;
+    }
+
+    switch( osGetMutexType(mutex) )
+    {
+    case OS_MUTEX_TYPE_STD:
+    case OS_MUTEX_TYPE_W:
+        if ( mutex->thread == currentThread )
+        {
+            osDecreaseMutexCount(mutex);
+            if ( osGetMutexCount(mutex) == 0 )
+            {
+                unlocked = TRUE;
+            }
+        }
+        break;
+
+    case OS_MUTEX_TYPE_R:
+        osDecreaseMutexCount(mutex);
+        if ( osGetMutexCount(mutex) == 0 )
+        {
+            unlocked = TRUE;
+        }
+        break;
+
+    default:
+        osTWarning("Illegal unlock mutex");
+        (void)osRestoreInterrupts(e);
+        return;
+        //osTPanic("Illegal unlock mutex\n");
+        //break;
+    }
+
+    //---- unlock mutex
+    if ( unlocked )
+    {
+        i_osDequeueItem(currentThread, mutex);
+        mutex->thread = NULL;
+        osSetMutexType( mutex, OS_MUTEX_TYPE_NONE );
+        osWakeupThread(&mutex->queue);
+    }
+
+    (void)osRestoreInterrupts(e);
+}
+
+/*---------------------------------------------------------------------------*
+  Name:         osUnlockMutexR
+
+  Description:  unlock mutex locked as READ access
+
+  Arguments:    mutex       pointer to mutex structure
+
+  Returns:      None
+ *---------------------------------------------------------------------------*/
+void osUnlockMutexR(OSMutex *mutex)
+{
+    i_osUnlockMutexCore( mutex, OS_MUTEX_TYPE_R );
+}
+
+/*---------------------------------------------------------------------------*
+  Name:         osUnlockMutexW
+
+  Description:  unlock mutex locked as WRITE access
+
+  Arguments:    mutex       pointer to mutex structure
+
+  Returns:      None
+ *---------------------------------------------------------------------------*/
+void osUnlockMutexW(OSMutex *mutex)
+{
+    i_osUnlockMutexCore( mutex, OS_MUTEX_TYPE_W );
+}
+
+/*---------------------------------------------------------------------------*
+  Name:         osUnlockMutexRW
+
+  Description:  unlock mutex locked as READ/WRITE access
+
+  Arguments:    mutex       pointer to mutex structure
+
+  Returns:      None
+ *---------------------------------------------------------------------------*/
+void osUnlockMutexRW(OSMutex *mutex)
+{
+    i_osUnlockMutexCore( mutex, OS_MUTEX_TYPE_NONE );
+}
+
+/*---------------------------------------------------------------------------*
+  Name:         osLockMutexFromRToW
+
+  Description:  Promote mutexR lock to mutexW lock without unlock.
+                Wait till success.
+
+  Arguments:    mutex       pointer to mutex structure
+
+  Returns:      None
+ *---------------------------------------------------------------------------*/
+void osLockMutexFromRToW(OSMutex *mutex)
+{
+    OSIntrMode e = osDisableInterrupts();
+    OSThread *currentThread = osGetCurrentThread();
+
+    while(1)
+    {
+        if ( osTryLockMutexFromRToW(mutex) )
+        {
+            break;
+        }
+
+        currentThread->mutex = mutex;
+        osSleepThread(&mutex->queue);
+        currentThread->mutex = NULL;
+    }
+
+    (void)osRestoreInterrupts(e);
+}
+
+/*---------------------------------------------------------------------------*
+  Name:         osTryLockMutexFromRToW
+
+  Description:  Try to promote mutexR lock to mutexW lock without unlock.
+
+  Arguments:    mutex       pointer to mutex structure
+
+  Returns:      TRUE if success
+ *---------------------------------------------------------------------------*/
+BOOL osTryLockMutexFromRToW(OSMutex *mutex)
+{
+    OSIntrMode e = osDisableInterrupts();
+    BOOL locked = FALSE;
+
+    //---- change mutex type if no other thread is locked. and mutex is R
+    if ( osGetMutexCount(mutex) == 1 && mutex->queue.head == NULL && osGetMutexType(mutex) == OS_MUTEX_TYPE_R )
+    {
+        osSetMutexType( mutex, OS_MUTEX_TYPE_W );
+        locked = TRUE;
+    }
+
+    (void)osRestoreInterrupts(e);
+    return locked;
+}
+
+/*---------------------------------------------------------------------------*
+  Name:         osLockMutexFromWToR
+
+  Description:  Demote mutexW lock to mutexR lock without unlock.
+                Wait till success.
+
+  Arguments:    mutex       pointer to mutex structure
+
+  Returns:      None
+ *---------------------------------------------------------------------------*/
+void osLockMutexFromWToR(OSMutex *mutex)
+{
+    OSIntrMode e = osDisableInterrupts();
+    OSThread *currentThread = osGetCurrentThread();
+
+    while(1)
+    {
+        if ( osTryLockMutexFromWToR(mutex) )
+        {
+            break;
+        }
+
+        currentThread->mutex = mutex;
+        osSleepThread(&mutex->queue);
+        currentThread->mutex = NULL;
+    }
+
+    (void)osRestoreInterrupts(e);
+}
+
+/*---------------------------------------------------------------------------*
+  Name:         osTryLockMutexFromWToR
+
+  Description:  Try to demote mutexW lock to mutexR lock without unlock.
+
+  Arguments:    mutex       pointer to mutex structure
+
+  Returns:      TRUE if success
+ *---------------------------------------------------------------------------*/
+BOOL osTryLockMutexFromWToR(OSMutex *mutex)
+{
+    OSIntrMode e = osDisableInterrupts();
+    BOOL locked = FALSE;
+
+    //---- change mutex type if no other thread is locked. and mutex is W
+    if ( osGetMutexCount(mutex) == 1 && mutex->queue.head == NULL && osGetMutexType(mutex) == OS_MUTEX_TYPE_W )
+    {
+        osSetMutexType( mutex, OS_MUTEX_TYPE_R );
+        locked = TRUE;
+    }
+
+    (void)osRestoreInterrupts(e);
+    return locked;
+}
+
+
+//===========================================================================
+//     MUTEX QUEUE
+//===========================================================================
+/*---------------------------------------------------------------------------*
+  Name:         i_osEnqueueTail
+
+  Description:  internal function.
+                add mutex to thread's mutex list
+
+  Arguments:    thread      pointer to thread
+                mutex       pointer to mutex to be add
+
+  Returns:      None.
+ *---------------------------------------------------------------------------*/
+void i_osEnqueueTail(OSThread *thread, OSMutex *mutex)
+{
+#ifndef SDK_THREAD_INFINITY
+    OSMutex *prev = thread->mutexQueueTail;
+
+    SDK_ASSERT(thread && mutex);
+
+    if (!prev)
+    {
+        thread->mutexQueueHead = mutex;
+    }
+    else
+    {
+        prev->next = mutex;
+    }
+
+    mutex->prev = prev;
+    mutex->next = NULL;
+    thread->mutexQueueTail = mutex;
+#else
+    OSMutex *prev = thread->mutexQueue.tail;
+
+    SDK_ASSERT(thread && mutex);
+
+    if (!prev)
+    {
+        thread->mutexQueue.head = mutex;
+    }
+    else
+    {
+        prev->link.next = mutex;
+    }
+
+    mutex->link.prev = prev;
+    mutex->link.next = NULL;
+    thread->mutexQueue.tail = mutex;
+#endif
+}
+
+/*---------------------------------------------------------------------------*
+  Name:         i_osDequeueItem
+
+  Description:  internal function.
+                remove specified mutex from thread's mutex list
+
+  Arguments:    thread      pointer to thread
+                mutex       pointer to mutex to be remove
+
+  Returns:      None.
+ *---------------------------------------------------------------------------*/
+void i_osDequeueItem(OSThread *thread, OSMutex *mutex)
+{
+#ifndef SDK_THREAD_INFINITY
+    OSMutex *next = mutex->next;
+    OSMutex *prev = mutex->prev;
+
+    SDK_ASSERT(thread && mutex);
+
+    if (!next)
+    {
+        thread->mutexQueueTail = prev;
+    }
+    else
+    {
+        next->prev = prev;
+    }
+
+    if (!prev)
+    {
+        thread->mutexQueueHead = next;
+    }
+    else
+    {
+        prev->next = next;
+    }
+#else
+    OSMutex *next = mutex->link.next;
+    OSMutex *prev = mutex->link.prev;
+
+    SDK_ASSERT(thread && mutex);
+
+    if (!next)
+    {
+        thread->mutexQueue.tail = prev;
+    }
+    else
+    {
+        next->link.prev = prev;
+    }
+
+    if (!prev)
+    {
+        thread->mutexQueue.head = next;
+    }
+    else
+    {
+        prev->link.next = next;
+    }
+#endif
+}
+
+/*---------------------------------------------------------------------------*
+  Name:         i_osDequeueHead
+
+  Description:  remove top mutex from thread's list, and return mutex
+
+  Arguments:    thread      pointer to thread
+
+  Returns:      mutex which listed at top of thread
+ *---------------------------------------------------------------------------*/
+OSMutex *i_osDequeueHead(OSThread *thread)
+{
+#ifndef SDK_THREAD_INFINITY
+    OSMutex *mutex = thread->mutexQueueHead;
+    OSMutex *next = mutex->next;
+
+    SDK_ASSERT(thread);
+
+    if (!next)
+    {
+        thread->mutexQueueTail = NULL;
+    }
+    else
+    {
+        next->prev = NULL;
+    }
+
+    thread->mutexQueueHead = next;
+#else
+    OSMutex *mutex = thread->mutexQueue.head;
+    OSMutex *next = mutex->link.next;
+
+    SDK_ASSERT(thread);
+
+    if (!next)
+    {
+        thread->mutexQueue.tail = NULL;
+    }
+    else
+    {
+        next->link.prev = NULL;
+    }
+
+    thread->mutexQueue.head = next;
+#endif
+
+    return mutex;
+}