MdePkg/Library/BaseLib/Arm/SpeculationBarrier.S

   1 ##------------------------------------------------------------------------------
   2 #
   3 # SpeculationBarrier() for AArch64
   4 #
   5 # Copyright (c) 2019, Linaro Ltd. All rights reserved.
   6 #
   7 # SPDX-License-Identifier: BSD-2-Clause-Patent
   8 #
   9 ##------------------------------------------------------------------------------
  10
  11 .text
  12 .p2align 2
  13
  14 GCC_ASM_EXPORT(SpeculationBarrier)
  15
  16
  17 #/**
  18 #  Uses as a barrier to stop speculative execution.
  19 #
  20 #  Ensures that no later instruction will execute speculatively, until all prior
  21 #  instructions have completed.
  22 #
  23 #**/
  24 #VOID
  25 #EFIAPI
  26 #SpeculationBarrier (
  27 #  VOID
  28 #  );
  29 #
  30 ASM_PFX(SpeculationBarrier):
  31     dsb
  32     isb
  33     bx   lr