MdePkg/Library/BaseLib/Cpu.c

   1 /** @file
   2   Base Library CPU Functions for all architectures.
   3
   4   Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
   5   This program and the accompanying materials
   6   are licensed and made available under the terms and conditions of the BSD License
   7   which accompanies this distribution.  The full text of the license may be found at
   8   http://opensource.org/licenses/bsd-license.php
   9
  10   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  11   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  12
  13 **/
  14
  15 #include "BaseLibInternals.h"
  16
  17
  18 /**
  19   Disables CPU interrupts and returns the interrupt state prior to the disable
  20   operation.
  21
  22   @retval TRUE  CPU interrupts were enabled on entry to this call.
  23   @retval FALSE CPU interrupts were disabled on entry to this call.
  24
  25 **/
  26 BOOLEAN
  27 EFIAPI
  28 SaveAndDisableInterrupts (
  29   VOID
  30   )
  31 {
  32   BOOLEAN                           InterruptState;
  33
  34   InterruptState = GetInterruptState ();
  35   DisableInterrupts ();
  36   return InterruptState;
  37 }
  38
  39 /**
  40   Set the current CPU interrupt state.
  41
  42   Sets the current CPU interrupt state to the state specified by
  43   InterruptState. If InterruptState is TRUE, then interrupts are enabled. If
  44   InterruptState is FALSE, then interrupts are disabled. InterruptState is
  45   returned.
  46
  47   @param  InterruptState  TRUE if interrupts should enabled. FALSE if
  48                           interrupts should be disabled.
  49
  50   @return InterruptState
  51
  52 **/
  53 BOOLEAN
  54 EFIAPI
  55 SetInterruptState (
  56   IN      BOOLEAN                   InterruptState
  57   )
  58 {
  59   if (InterruptState) {
  60     EnableInterrupts ();
  61   } else {
  62     DisableInterrupts ();
  63   }
  64   return InterruptState;
  65 }