MdePkg/Library/BaseTimerLibNullTemplate/TimerLibNull.c

   1 /** @file
   2   A non-functional instance of the Timer Library.
   3
   4   Copyright (c) 2007, 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 <Base.h>
  17
  18
  19 #include <Library/TimerLib.h>
  20 #include <Library/DebugLib.h>
  21
  22 /**
  23   Stalls the CPU for at least the given number of microseconds.
  24
  25   Stalls the CPU for the number of microseconds specified by MicroSeconds.
  26
  27   @param  MicroSeconds  The minimum number of microseconds to delay.
  28
  29   @return MicroSeconds
  30
  31 **/
  32 UINTN
  33 EFIAPI
  34 MicroSecondDelay (
  35   IN      UINTN                     MicroSeconds
  36   )
  37 {
  38   ASSERT (FALSE);
  39   return MicroSeconds;
  40 }
  41
  42 /**
  43   Stalls the CPU for at least the given number of nanoseconds.
  44
  45   Stalls the CPU for the number of nanoseconds specified by NanoSeconds.
  46
  47   @param  NanoSeconds The minimum number of nanoseconds to delay.
  48
  49   @return NanoSeconds
  50
  51 **/
  52 UINTN
  53 EFIAPI
  54 NanoSecondDelay (
  55   IN      UINTN                     NanoSeconds
  56   )
  57 {
  58   ASSERT (FALSE);
  59   return 0;
  60 }
  61
  62 /**
  63   Retrieves the current value of a 64-bit free running performance counter.
  64
  65   Retrieves the current value of a 64-bit free running performance counter. The
  66   counter can either count up by 1 or count down by 1. If the physical
  67   performance counter counts by a larger increment, then the counter values
  68   must be translated. The properties of the counter can be retrieved from
  69   GetPerformanceCounterProperties().
  70
  71   @return The current value of the free running performance counter.
  72
  73 **/
  74 UINT64
  75 EFIAPI
  76 GetPerformanceCounter (
  77   VOID
  78   )
  79 {
  80   ASSERT (FALSE);
  81   return 0;
  82 }
  83
  84 /**
  85   Retrieves the 64-bit frequency in Hz and the range of performance counter
  86   values.
  87
  88   If StartValue is not NULL, then the value that the performance counter starts
  89   with immediately after is it rolls over is returned in StartValue. If
  90   EndValue is not NULL, then the value that the performance counter end with
  91   immediately before it rolls over is returned in EndValue. The 64-bit
  92   frequency of the performance counter in Hz is always returned. If StartValue
  93   is less than EndValue, then the performance counter counts up. If StartValue
  94   is greater than EndValue, then the performance counter counts down. For
  95   example, a 64-bit free running counter that counts up would have a StartValue
  96   of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter
  97   that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0.
  98
  99   @param  StartValue  The value the performance counter starts with when it
 100                       rolls over.
 101   @param  EndValue    The value that the performance counter ends with before
 102                       it rolls over.
 103
 104   @return The frequency in Hz.
 105
 106 **/
 107 UINT64
 108 EFIAPI
 109 GetPerformanceCounterProperties (
 110   OUT      UINT64                    *StartValue,  OPTIONAL
 111   OUT      UINT64                    *EndValue     OPTIONAL
 112   )
 113 {
 114   ASSERT (FALSE);
 115   return 0;
 116 }