/* Reads and returns the current value of TSC. This function is only available on IA-32 and X64. */
UINT64 EFIAPI AsmReadTsc(VOID)
/* Reads and returns the current value of TSC. This function is only available on IA-32 and X64. */
UINT64 EFIAPI AsmReadTsc(VOID)
{
  UINT64  Data;
  __asm__ __volatile__ (
    "rdtsc"
    : "=A" (Data)
  );
  return Data;
}