MdePkg/Library/BaseLib/AArch64/GetInterruptsState.S

   1 #------------------------------------------------------------------------------
   2 #
   3 # GetInterruptState() function for AArch64
   4 #
   5 # Copyright (c) 2006 - 2009, Intel Corporation. All rights reserved.<BR>
   6 # Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
   7 # Portions copyright (c) 2011 - 2013, ARM Ltd. All rights reserved.<BR>
   8 # This program and the accompanying materials
   9 # are licensed and made available under the terms and conditions of the BSD License
  10 # which accompanies this distribution.  The full text of the license may be found at
  11 # http://opensource.org/licenses/bsd-license.php.
  12 #
  13 # THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  14 # WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  15 #
  16 #------------------------------------------------------------------------------
  17
  18 .text
  19 .p2align 2
  20 GCC_ASM_EXPORT(GetInterruptState)
  21
  22 #/**
  23 #  Retrieves the current CPU interrupt state.
  24 #
  25 #  Returns TRUE is interrupts are currently enabled. Otherwise
  26 #  returns FALSE.
  27 #
  28 #  @retval TRUE  CPU interrupts are enabled.
  29 #  @retval FALSE CPU interrupts are disabled.
  30 #
  31 #**/
  32 #
  33 #BOOLEAN
  34 #EFIAPI
  35 #GetInterruptState (
  36 #  VOID
  37 # );
  38 #
  39 ASM_PFX(GetInterruptState):
  40     mrs    x0, daif
  41     tst    x0, #2            // Check if IRQ is enabled. Enabled if 0.
  42     mov    w0, #0
  43     mov    w1, #1
  44     csel   w0, w1, w0, ne
  45     ret