MdePkg/Library/BaseLib/Ia32/ReadTsc.c

   1 /** @file
   2   AsmReadTsc function
   3
   4   Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
   5   SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7 **/
   8
   9 /**
  10   Reads the current value of Time Stamp Counter (TSC).
  11
  12   Reads and returns the current value of TSC. This function is only available
  13   on IA-32 and x64.
  14
  15   @return The current value of TSC
  16
  17 **/
  18 UINT64
  19 EFIAPI
  20 AsmReadTsc (
  21   VOID
  22   )
  23 {
  24   _asm {
  25     rdtsc
  26   }
  27 }