MdePkg/Library/BaseLib/Cpu.c

   1 /** @file
   2   Base Library CPU Functions for all architectures.
   3
   4   Copyright (c) 2006, Intel Corporation<BR>
   5   All rights reserved. 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 //
  16 // Include common header file for this module.
  17 //
  18 #include <BaseLibInternals.h>
  19
  20
  21 /**
  22   Disables CPU interrupts and returns the interrupt state prior to the disable
  23   operation.
  24
  25   Disables CPU interrupts and returns the interrupt state prior to the disable
  26   operation.
  27
  28   @retval TRUE  CPU interrupts were enabled on entry to this call.
  29   @retval FALSE CPU interrupts were disabled on entry to this call.
  30
  31 **/
  32 BOOLEAN
  33 EFIAPI
  34 SaveAndDisableInterrupts (
  35   VOID
  36   )
  37 {
  38   BOOLEAN                           InterruptState;
  39
  40   InterruptState = GetInterruptState ();
  41   DisableInterrupts ();
  42   return InterruptState;
  43 }
  44
  45 /**
  46   Set the current CPU interrupt state.
  47
  48   Sets the current CPU interrupt state to the state specified by
  49   InterruptState. If InterruptState is TRUE, then interrupts are enabled. If
  50   InterruptState is FALSE, then interrupts are disabled. InterruptState is
  51   returned.
  52
  53   @param  InterruptState  TRUE if interrupts should enabled. FALSE if
  54                           interrupts should be disabled.
  55
  56   @return InterruptState
  57
  58 **/
  59 BOOLEAN
  60 EFIAPI
  61 SetInterruptState (
  62   IN      BOOLEAN                   InterruptState
  63   )
  64 {
  65   if (InterruptState) {
  66     EnableInterrupts ();
  67   } else {
  68     DisableInterrupts ();
  69   }
  70   return InterruptState;
  71 }