/*---------------------------------------------------------------------------*
  Project:  CtrBrom - OS
  File:     os_protectionUnit.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/os.h>
#include <brom/code32.h>

//======================================================================
//          protection unit
//======================================================================
/*---------------------------------------------------------------------------*
  Name:         osEnableProtectionUnit

  Description:  enable protection unit

  Arguments:    None

  Returns:      None
 *---------------------------------------------------------------------------*/
asm void osEnableProtectionUnit( void )
{
    mrc     p15, 0, r0, c1, c0, 0
    orr     r0, r0, #HW_C1_PROTECT_UNIT_ENABLE
    mcr     p15, 0, r0, c1, c0, 0
    bx      lr
}

/*---------------------------------------------------------------------------*
  Name:         osDisableProtectionUnit

  Description:  disable protection unit

  Arguments:    None

  Returns:      None
 *---------------------------------------------------------------------------*/
asm void osDisableProtectionUnit( void )
{
    mrc     p15, 0, r0, c1, c0, 0
    bic     r0, r0, #HW_C1_PROTECT_UNIT_ENABLE
    mcr     p15, 0, r0, c1, c0, 0
    bx      lr
}

/*---------------------------------------------------------------------------*
  Name:         i_osFinalizeProtectionUnit

  Description:  finalize protection unit

  Arguments:    None

  Returns:      None
 *---------------------------------------------------------------------------*/
asm void i_osFinalizeProtectionUnit( void )
{
        // プロテクションユニット＆キャッシュ無効。ITCM ＆ DTCMは有効
        ldr         r0, = HW_C1_ITCM_ENABLE | HW_C1_DTCM_ENABLE  | HW_C1_EXCEPT_VEC_UPPER | HW_C1_SB1_BITSET
        mcr         p15, 0, r0, c1, c0, 0

        // ITCMの割り当てを解除
//        mov         r0, #0
//        mcr         p15, 0, r0, c6, c5, 0

        // DTCMの割り当てを解除
//      mov         r0,#0
//      mcr         p15, 0, r0, c9, c1, 0

        // キャッシュ無効化
        mov         r0, #0
        mcr         p15, 0, r0, c7, c5, 0           // 命令キャッシュ
        mcr         p15, 0, r0, c7, c6, 0           // データキャッシュ

        // ライトバッファ エンプティ待ち
        mcr         p15, 0, r0, c7, c10, 4

        bx          lr
}