EmulatorPkg/Library/PeiTimerLib/PeiTimerLib.c

   1 /** @file
   2   A non-functional instance of the Timer Library.
   3
   4   Copyright (c) 2007 - 2010, Intel Corporation. All rights reserved.<BR>
   5   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 #include <PiPei.h>
  16 #include <Library/TimerLib.h>
  17 #include <Library/DebugLib.h>
  18 #include <Library/PeiServicesLib.h>
  19
  20 #include <Ppi/EmuThunk.h>
  21 #include <Protocol/EmuThunk.h>
  22
  23 /**
  24   Stalls the CPU for at least the given number of microseconds.
  25
  26   Stalls the CPU for the number of microseconds specified by MicroSeconds.
  27
  28   @param  MicroSeconds  The minimum number of microseconds to delay.
  29
  30   @return The value of MicroSeconds inputted.
  31
  32 **/
  33 UINTN
  34 EFIAPI
  35 MicroSecondDelay (
  36   IN      UINTN                     MicroSeconds
  37   )
  38 {
  39   return NanoSecondDelay (MicroSeconds * 1000);
  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 The value of NanoSeconds inputted.
  50
  51 **/
  52 UINTN
  53 EFIAPI
  54 NanoSecondDelay (
  55   IN      UINTN                     NanoSeconds
  56   )
  57 {
  58   EMU_THUNK_PPI           *ThunkPpi;
  59   EFI_STATUS              Status;
  60   EMU_THUNK_PROTOCOL      *Thunk;
  61
  62   //
  63   // Locate EmuThunkPpi for
  64   //
  65   Status = PeiServicesLocatePpi (
  66               &gEmuThunkPpiGuid,
  67               0,
  68               NULL,
  69               (VOID **) &ThunkPpi
  70              );
  71   if (!EFI_ERROR (Status)) {
  72     Thunk  = (EMU_THUNK_PROTOCOL *)ThunkPpi->Thunk ();
  73     Thunk->Sleep (NanoSeconds * 100);
  74     return NanoSeconds;
  75   }
  76
  77   return 0;
  78 }
  79
  80 /**
  81   Retrieves the current value of a 64-bit free running performance counter.
  82
  83   The counter can either count up by 1 or count down by 1. If the physical
  84   performance counter counts by a larger increment, then the counter values
  85   must be translated. The properties of the counter can be retrieved from
  86   GetPerformanceCounterProperties().
  87
  88   @return The current value of the free running performance counter.
  89
  90 **/
  91 UINT64
  92 EFIAPI
  93 GetPerformanceCounter (
  94   VOID
  95   )
  96 {
  97   EMU_THUNK_PPI           *ThunkPpi;
  98   EFI_STATUS              Status;
  99   EMU_THUNK_PROTOCOL      *Thunk;
 100
 101   //
 102   // Locate EmuThunkPpi for
 103   //
 104   Status = PeiServicesLocatePpi (
 105               &gEmuThunkPpiGuid,
 106               0,
 107               NULL,
 108               (VOID **) &ThunkPpi
 109              );
 110   if (!EFI_ERROR (Status)) {
 111     Thunk  = (EMU_THUNK_PROTOCOL *)ThunkPpi->Thunk ();
 112     return  Thunk->QueryPerformanceCounter ();
 113   }
 114
 115   return 0;
 116 }
 117
 118 /**
 119   Retrieves the 64-bit frequency in Hz and the range of performance counter
 120   values.
 121
 122   If StartValue is not NULL, then the value that the performance counter starts
 123   with immediately after is it rolls over is returned in StartValue. If
 124   EndValue is not NULL, then the value that the performance counter end with
 125   immediately before it rolls over is returned in EndValue. The 64-bit
 126   frequency of the performance counter in Hz is always returned. If StartValue
 127   is less than EndValue, then the performance counter counts up. If StartValue
 128   is greater than EndValue, then the performance counter counts down. For
 129   example, a 64-bit free running counter that counts up would have a StartValue
 130   of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter
 131   that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0.
 132
 133   @param  StartValue  The value the performance counter starts with when it
 134                       rolls over.
 135   @param  EndValue    The value that the performance counter ends with before
 136                       it rolls over.
 137
 138   @return The frequency in Hz.
 139
 140 **/
 141 UINT64
 142 EFIAPI
 143 GetPerformanceCounterProperties (
 144   OUT      UINT64                    *StartValue,  OPTIONAL
 145   OUT      UINT64                    *EndValue     OPTIONAL
 146   )
 147 {
 148   EMU_THUNK_PPI           *ThunkPpi;
 149   EFI_STATUS              Status;
 150   EMU_THUNK_PROTOCOL      *Thunk;
 151
 152   //
 153   // Locate EmuThunkPpi for
 154   //
 155   Status = PeiServicesLocatePpi (
 156               &gEmuThunkPpiGuid,
 157               0,
 158               NULL,
 159               (VOID **) &ThunkPpi
 160              );
 161   if (!EFI_ERROR (Status)) {
 162     if (StartValue != NULL) {
 163       *StartValue = 0ULL;
 164     }
 165     if (EndValue != NULL) {
 166       *EndValue = (UINT64)-1LL;
 167     }
 168
 169     Thunk  = (EMU_THUNK_PROTOCOL *)ThunkPpi->Thunk ();
 170     return  Thunk->QueryPerformanceFrequency ();
 171   }
 172
 173   return 0;
 174 }