EdkCompatibilityPkg/Foundation/Library/EdkIIGlueLib/Library/BaseTimerLibLocalApic/Ipf/IpfTimerLib.c

   1 /*++
   2
   3 Copyright (c) 2004 - 2006, Intel Corporation
   4 All rights reserved. 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   IpfTimerLib.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 /**
  31   Performs a delay measured as number of ticks.
  32
  33   An internal function to perform a delay measured as number of ticks. It's
  34   invoked by MicroSecondDelay() and NanoSecondDelay().
  35
  36   @param  Delay Number of ticks to delay.
  37
  38 **/
  39 STATIC
  40 VOID
  41 InternalIpfDelay (
  42   IN      INT64                     Delay
  43   )
  44 {
  45   INT64                             Ticks;
  46
  47   //
  48   // The target timer count is calculated here
  49   //
  50   Ticks = IpfReadItc () + Delay;
  51
  52   //
  53   // Wait until time out
  54   // Delay > 2^63 could not be handled by this function
  55   // Timer wrap-arounds are handled correctly by this function
  56   //
  57   while (Ticks - IpfReadItc () >= 0);
  58 }
  59
  60 /**
  61   Stalls the CPU for at least the given number of microseconds.
  62
  63   Stalls the CPU for the number of microseconds specified by MicroSeconds.
  64
  65   @param  MicroSeconds  The minimum number of microseconds to delay.
  66
  67   @return MicroSeconds
  68
  69 **/
  70 UINTN
  71 EFIAPI
  72 MicroSecondDelay (
  73   IN      UINTN                     MicroSeconds
  74   )
  75 {
  76   InternalIpfDelay (
  77     GetPerformanceCounterProperties (NULL, NULL) *
  78     MicroSeconds /
  79     1000000
  80     );
  81   return MicroSeconds;
  82 }
  83
  84 /**
  85   Stalls the CPU for at least the given number of nanoseconds.
  86
  87   Stalls the CPU for the number of nanoseconds specified by NanoSeconds.
  88
  89   @param  NanoSeconds The minimum number of nanoseconds to delay.
  90
  91   @return NanoSeconds
  92
  93 **/
  94 UINTN
  95 EFIAPI
  96 NanoSecondDelay (
  97   IN      UINTN                     NanoSeconds
  98   )
  99 {
 100   InternalIpfDelay (
 101     GetPerformanceCounterProperties (NULL, NULL) *
 102     NanoSeconds /
 103     1000000000
 104     );
 105   return NanoSeconds;
 106 }
 107
 108 /**
 109   Retrieves the current value of a 64-bit free running performance counter.
 110
 111   Retrieves the current value of a 64-bit free running performance counter. The
 112   counter can either count up by 1 or count down by 1. If the physical
 113   performance counter counts by a larger increment, then the counter values
 114   must be translated. The properties of the counter can be retrieved from
 115   GetPerformanceCounterProperties().
 116
 117   @return The current value of the free running performance counter.
 118
 119 **/
 120 UINT64
 121 EFIAPI
 122 GetPerformanceCounter (
 123   VOID
 124   )
 125 {
 126   return IpfReadItc ();
 127 }
 128
 129 /**
 130   Retrieves the 64-bit frequency in Hz and the range of performance counter
 131   values.
 132
 133   If StartValue is not NULL, then the value that the performance counter starts
 134   with immediately after is it rolls over is returned in StartValue. If
 135   EndValue is not NULL, then the value that the performance counter end with
 136   immediately before it rolls over is returned in EndValue. The 64-bit
 137   frequency of the performance counter in Hz is always returned. If StartValue
 138   is less than EndValue, then the performance counter counts up. If StartValue
 139   is greater than EndValue, then the performance counter counts down. For
 140   example, a 64-bit free running counter that counts up would have a StartValue
 141   of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter
 142   that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0.
 143
 144   @param  StartValue  The value the performance counter starts with when it
 145                       rolls over.
 146   @param  EndValue    The value that the performance counter ends with before
 147                       it rolls over.
 148
 149   @return The frequency in Hz.
 150
 151 **/
 152 UINT64
 153 EFIAPI
 154 GetPerformanceCounterProperties (
 155   OUT      UINT64                    *StartValue,  OPTIONAL
 156   OUT      UINT64                    *EndValue     OPTIONAL
 157   )
 158 {
 159   PAL_PROC_RETURN                   PalRet;
 160   UINT64                            BaseFrequence;
 161
 162   PalRet = PalCallStatic (NULL, 13, 0, 0, 0);
 163   ASSERT (PalRet.Status == 0);
 164   BaseFrequence = PalRet.r9;
 165
 166   PalRet = PalCallStatic (NULL, 14, 0, 0, 0);
 167   ASSERT (PalRet.Status == 0);
 168
 169   if (StartValue != NULL) {
 170     *StartValue = 0;
 171   }
 172
 173   if (EndValue != NULL) {
 174     *EndValue = (UINT64)(-1);
 175   }
 176
 177   return BaseFrequence * (PalRet.r11 >> 32) / (UINT32)PalRet.r11;
 178 }