EdkCompatibilityPkg/Foundation/Library/EdkIIGlueLib/Library/BaseTimerLibLocalApic/Ebc/EbcTimerLib.c

   1 /*++
   2
   3 Copyright (c) 2004 - 2006, Intel Corporation. All rights reserved.<BR>
   4 This program and the accompanying materials
   5 are licensed and made available under the terms and conditions of the BSD License
   6 which accompanies this distribution.  The full text of the license may be found at
   7 http://opensource.org/licenses/bsd-license.php
   8
   9 THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10 WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11
  12
  13 Module Name:
  14
  15   EbcTimerLib.c
  16
  17 Abstract:
  18
  19   Timer Library functions built upon local APIC on IA32/x64.
  20
  21   @bug Should use PCD to retrieve all the constants including index of
  22   the IA32_APIC_BASE MSR, the offsets of InitialCount, CorrentCount
  23   and DivideConfiguration.
  24
  25 --*/
  26
  27 #include "EdkIIGlueBase.h"
  28
  29 /**
  30   Stalls the CPU for at least the given number of microseconds.
  31
  32   Stalls the CPU for the number of microseconds specified by MicroSeconds.
  33
  34   @param  MicroSeconds  The minimum number of microseconds to delay.
  35
  36   @return MicroSeconds
  37
  38 **/
  39 UINTN
  40 EFIAPI
  41 MicroSecondDelay (
  42   IN      UINTN                     MicroSeconds
  43   )
  44 {
  45   //
  46   // EBC architecture does not support local APIC timer.
  47   //
  48   ASSERT (FALSE);
  49   return MicroSeconds;
  50 }
  51
  52 /**
  53   Stalls the CPU for at least the given number of nanoseconds.
  54
  55   Stalls the CPU for the number of nanoseconds specified by NanoSeconds.
  56
  57   @param  NanoSeconds The minimum number of nanoseconds to delay.
  58
  59   @return NanoSeconds
  60
  61 **/
  62 UINTN
  63 EFIAPI
  64 NanoSecondDelay (
  65   IN      UINTN                     NanoSeconds
  66   )
  67 {
  68   //
  69   // EBC architecture does not support local APIC timer.
  70   //
  71   ASSERT (FALSE);
  72   return NanoSeconds;
  73 }
  74
  75 /**
  76   Retrieves the current value of a 64-bit free running performance counter.
  77
  78   Retrieves the current value of a 64-bit free running performance counter. The
  79   counter can either count up by 1 or count down by 1. If the physical
  80   performance counter counts by a larger increment, then the counter values
  81   must be translated. The properties of the counter can be retrieved from
  82   GetPerformanceCounterProperties().
  83
  84   @return The current value of the free running performance counter.
  85
  86 **/
  87 UINT64
  88 EFIAPI
  89 GetPerformanceCounter (
  90   VOID
  91   )
  92 {
  93   //
  94   // EBC architecture does not support local APIC timer.
  95   //
  96   ASSERT (FALSE);
  97   return 0;
  98 }
  99
 100 /**
 101   Retrieves the 64-bit frequency in Hz and the range of performance counter
 102   values.
 103
 104   If StartValue is not NULL, then the value that the performance counter starts
 105   with immediately after is it rolls over is returned in StartValue. If
 106   EndValue is not NULL, then the value that the performance counter end with
 107   immediately before it rolls over is returned in EndValue. The 64-bit
 108   frequency of the performance counter in Hz is always returned. If StartValue
 109   is less than EndValue, then the performance counter counts up. If StartValue
 110   is greater than EndValue, then the performance counter counts down. For
 111   example, a 64-bit free running counter that counts up would have a StartValue
 112   of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter
 113   that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0.
 114
 115   @param  StartValue  The value the performance counter starts with when it
 116                       rolls over.
 117   @param  EndValue    The value that the performance counter ends with before
 118                       it rolls over.
 119
 120   @return The frequency in Hz.
 121
 122 **/
 123 UINT64
 124 EFIAPI
 125 GetPerformanceCounterProperties (
 126   OUT      UINT64                    *StartValue,  OPTIONAL
 127   OUT      UINT64                    *EndValue     OPTIONAL
 128   )
 129 {
 130   //
 131   // EBC architecture does not support local APIC timer.
 132   //
 133   ASSERT (FALSE);
 134   return 0;
 135 }