MdePkg/Library/BaseTimerLibNullTemplate/TimerLibNull.c

   1 /** @file
   2   A non-functional instance of the Timer Library.
   3
   4   Copyright (c) 2007 - 2011, Intel Corporation. All rights reserved.<BR>
   5   SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7 **/
   8
   9 #include <Base.h>
  10 #include <Library/TimerLib.h>
  11 #include <Library/DebugLib.h>
  12
  13 /**
  14   Stalls the CPU for at least the given number of microseconds.
  15
  16   Stalls the CPU for the number of microseconds specified by MicroSeconds.
  17
  18   @param  MicroSeconds  The minimum number of microseconds to delay.
  19
  20   @return The value of MicroSeconds inputted.
  21
  22 **/
  23 UINTN
  24 EFIAPI
  25 MicroSecondDelay (
  26   IN      UINTN                     MicroSeconds
  27   )
  28 {
  29   ASSERT (FALSE);
  30   return MicroSeconds;
  31 }
  32
  33 /**
  34   Stalls the CPU for at least the given number of nanoseconds.
  35
  36   Stalls the CPU for the number of nanoseconds specified by NanoSeconds.
  37
  38   @param  NanoSeconds The minimum number of nanoseconds to delay.
  39
  40   @return The value of NanoSeconds inputted.
  41
  42 **/
  43 UINTN
  44 EFIAPI
  45 NanoSecondDelay (
  46   IN      UINTN                     NanoSeconds
  47   )
  48 {
  49   ASSERT (FALSE);
  50   return 0;
  51 }
  52
  53 /**
  54   Retrieves the current value of a 64-bit free running performance counter.
  55
  56   The counter can either count up by 1 or count down by 1. If the physical
  57   performance counter counts by a larger increment, then the counter values
  58   must be translated. The properties of the counter can be retrieved from
  59   GetPerformanceCounterProperties().
  60
  61   @return The current value of the free running performance counter.
  62
  63 **/
  64 UINT64
  65 EFIAPI
  66 GetPerformanceCounter (
  67   VOID
  68   )
  69 {
  70   ASSERT (FALSE);
  71   return 0;
  72 }
  73
  74 /**
  75   Retrieves the 64-bit frequency in Hz and the range of performance counter
  76   values.
  77
  78   If StartValue is not NULL, then the value that the performance counter starts
  79   with immediately after is it rolls over is returned in StartValue. If
  80   EndValue is not NULL, then the value that the performance counter end with
  81   immediately before it rolls over is returned in EndValue. The 64-bit
  82   frequency of the performance counter in Hz is always returned. If StartValue
  83   is less than EndValue, then the performance counter counts up. If StartValue
  84   is greater than EndValue, then the performance counter counts down. For
  85   example, a 64-bit free running counter that counts up would have a StartValue
  86   of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter
  87   that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0.
  88
  89   @param  StartValue  The value the performance counter starts with when it
  90                       rolls over.
  91   @param  EndValue    The value that the performance counter ends with before
  92                       it rolls over.
  93
  94   @return The frequency in Hz.
  95
  96 **/
  97 UINT64
  98 EFIAPI
  99 GetPerformanceCounterProperties (
 100   OUT      UINT64                    *StartValue,  OPTIONAL
 101   OUT      UINT64                    *EndValue     OPTIONAL
 102   )
 103 {
 104   ASSERT (FALSE);
 105
 106   return (UINT64)(-1);
 107 }
 108
 109 /**
 110   Converts elapsed ticks of performance counter to time in nanoseconds.
 111
 112   This function converts the elapsed ticks of running performance counter to
 113   time value in unit of nanoseconds.
 114
 115   @param  Ticks     The number of elapsed ticks of running performance counter.
 116
 117   @return The elapsed time in nanoseconds.
 118
 119 **/
 120 UINT64
 121 EFIAPI
 122 GetTimeInNanoSecond (
 123   IN      UINT64                     Ticks
 124   )
 125 {
 126   ASSERT (FALSE);
 127   return 0;
 128 }