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 // The package level header files this module uses
  17 //
  18 #include <Base.h>
  19 //
  20 // The protocols, PPI and GUID defintions for this module
  21 //
  22 //
  23 // The Library classes this module consumes
  24 //
  25 #include <Library/TimerLib.h>
  26 #include <Library/DebugLib.h>
  27
  28 /**
  29   Stalls the CPU for at least the given number of microseconds.
  30
  31   Stalls the CPU for the number of microseconds specified by MicroSeconds.
  32
  33   @param  MicroSeconds  The minimum number of microseconds to delay.
  34
  35   @return MicroSeconds
  36
  37 **/
  38 UINTN
  39 EFIAPI
  40 MicroSecondDelay (
  41   IN      UINTN                     MicroSeconds
  42   )
  43 {
  44   ASSERT (FALSE);
  45   return MicroSeconds;
  46 }
  47
  48 /**
  49   Stalls the CPU for at least the given number of nanoseconds.
  50
  51   Stalls the CPU for the number of nanoseconds specified by NanoSeconds.
  52
  53   @param  NanoSeconds The minimum number of nanoseconds to delay.
  54
  55   @return NanoSeconds
  56
  57 **/
  58 UINTN
  59 EFIAPI
  60 NanoSecondDelay (
  61   IN      UINTN                     NanoSeconds
  62   )
  63 {
  64   ASSERT (FALSE);
  65   return 0;
  66 }
  67
  68 /**
  69   Retrieves the current value of a 64-bit free running performance counter.
  70
  71   Retrieves the current value of a 64-bit free running performance counter. The
  72   counter can either count up by 1 or count down by 1. If the physical
  73   performance counter counts by a larger increment, then the counter values
  74   must be translated. The properties of the counter can be retrieved from
  75   GetPerformanceCounterProperties().
  76
  77   @return The current value of the free running performance counter.
  78
  79 **/
  80 UINT64
  81 EFIAPI
  82 GetPerformanceCounter (
  83   VOID
  84   )
  85 {
  86   ASSERT (FALSE);
  87   return 0;
  88 }
  89
  90 /**
  91   Retrieves the 64-bit frequency in Hz and the range of performance counter
  92   values.
  93
  94   If StartValue is not NULL, then the value that the performance counter starts
  95   with immediately after is it rolls over is returned in StartValue. If
  96   EndValue is not NULL, then the value that the performance counter end with
  97   immediately before it rolls over is returned in EndValue. The 64-bit
  98   frequency of the performance counter in Hz is always returned. If StartValue
  99   is less than EndValue, then the performance counter counts up. If StartValue
 100   is greater than EndValue, then the performance counter counts down. For
 101   example, a 64-bit free running counter that counts up would have a StartValue
 102   of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter
 103   that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0.
 104
 105   @param  StartValue  The value the performance counter starts with when it
 106                       rolls over.
 107   @param  EndValue    The value that the performance counter ends with before
 108                       it rolls over.
 109
 110   @return The frequency in Hz.
 111
 112 **/
 113 UINT64
 114 EFIAPI
 115 GetPerformanceCounterProperties (
 116   OUT      UINT64                    *StartValue,  OPTIONAL
 117   OUT      UINT64                    *EndValue     OPTIONAL
 118   )
 119 {
 120   ASSERT (FALSE);
 121   return 0;
 122 }