diff --git a/include/firm/os/ARM9/os_cache_tag.h b/include/firm/os/ARM9/os_cache_tag.h
new file mode 100644
index 00000000..7116eaf6
--- /dev/null
+++ b/include/firm/os/ARM9/os_cache_tag.h
@@ -0,0 +1,151 @@
+/*---------------------------------------------------------------------------*
+  Project:  TwlFirm - OS - include 
+  File:     os_cache_tag.h
+
+  Copyright 2007 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::            $
+  $Rev$
+  $Author$
+ *---------------------------------------------------------------------------*/
+
+#ifndef TWL_OS_CACHE_TAG_H_
+#define TWL_OS_CACHE_TAG_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <twl/misc.h>
+#include <twl/types.h>
+
+//===========================================================================
+//              DATA CACHE (for specified range)
+//===========================================================================
+/*---------------------------------------------------------------------------*
+  Name:         DC_ClearTagAll
+
+  Description:  clear tag in data cache
+
+  Arguments:    None
+
+  Returns:      None.
+ *---------------------------------------------------------------------------*/
+void    DC_ClearTagAll( void );
+
+/*---------------------------------------------------------------------------*
+  Name:         DC_ClearDataAll
+
+  Description:  clear data in data cache
+
+  Arguments:    None
+
+  Returns:      None.
+ *---------------------------------------------------------------------------*/
+void    DC_ClearDataAll( void );
+
+/*---------------------------------------------------------------------------*
+  Name:         DC_FillTagAll
+
+  Description:  clear tag in data cache
+
+  Arguments:    data :  fill data
+
+  Returns:      None.
+ *---------------------------------------------------------------------------*/
+void    DC_FillTagAll( u32 data );
+
+/*---------------------------------------------------------------------------*
+  Name:         DC_FillDataAll
+
+  Description:  fill data in data cache
+
+  Arguments:    data :  fill data
+
+  Returns:      None.
+ *---------------------------------------------------------------------------*/
+void    DC_FillDataAll( u32 data );
+
+/*---------------------------------------------------------------------------*
+  Name:         DC_GetTagAndDataAll
+
+  Description:  get tag and data in data cache
+
+  Arguments:    tag           tag address
+                data          data address
+
+  Returns:      None.
+ *---------------------------------------------------------------------------*/
+void    DC_GetTagAndDataAll( void* tag, void* data );
+
+//===========================================================================
+//              INSTRUCTION CACHE
+//===========================================================================
+/*---------------------------------------------------------------------------*
+  Name:         IC_ClearTagAll
+
+  Description:  clear tag in instruction cache
+
+  Arguments:    None
+
+  Returns:      None.
+ *---------------------------------------------------------------------------*/
+void    IC_ClearTagAll( void );
+
+/*---------------------------------------------------------------------------*
+  Name:         IC_ClearInstructionAll
+
+  Description:  clear instruction in instruction cache
+
+  Arguments:    None
+
+  Returns:      None.
+ *---------------------------------------------------------------------------*/
+void    IC_ClearInstructionAll( void );
+
+/*---------------------------------------------------------------------------*
+  Name:         IC_FillTagAll
+
+  Description:  fill tag in instruction cache
+
+  Arguments:    None
+
+  Returns:      None.
+ *---------------------------------------------------------------------------*/
+void    IC_FillTagAll( u32 data );
+
+/*---------------------------------------------------------------------------*
+  Name:         IC_FillInstructionAll
+
+  Description:  fill instruction in instruction cache
+
+  Arguments:    data :  fill data
+
+  Returns:      None.
+ *---------------------------------------------------------------------------*/
+void    IC_FillInstructionAll( u32 data );
+
+/*---------------------------------------------------------------------------*
+  Name:         IC_GetTagAndInstructionAll
+
+  Description:  get tag and instruction in instruction cache
+
+  Arguments:    tag           tag address
+                inst          instruction address
+
+  Returns:      None.
+ *---------------------------------------------------------------------------*/
+void    IC_GetTagAndInstructionAll( void* tag, void* inst );
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
+/* TWL_OS_CACHE_TAG_H_ */
+#endif