MdePkg/Library/BaseTimerLibLocalApic/Ipf/IpfTimerLib.c

   1 /** @file
   2   Timer Library functions built upon local APIC on IA32/x64.
   3
   4   @bug Should use PCD to retrieve all the constants including index of
   5   the IA32_APIC_BASE MSR, the offsets of InitialCount, CorrentCount
   6   and DivideConfiguration.
   7
   8   Copyright (c) 2006, Intel Corporation<BR>
   9   All rights reserved. This program and the accompanying materials
  10   are licensed and made available under the terms and conditions of the BSD License
  11   which accompanies this distribution.  The full text of the license may be found at
  12   http://opensource.org/licenses/bsd-license.php
  13
  14   THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  15   WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  16
  17   Module Name:  IpfTimerLib.c
  18
  19 **/
  20
  21 UINT64
  22 ReadItc (
  23   VOID
  24   );
  25
  26 typedef struct {
  27   UINT64                            Status;
  28   UINT64                            r9;
  29   UINT64                            r10;
  30   UINT64                            r11;
  31 } PAL_PROC_RETURN;
  32
  33 PAL_PROC_RETURN
  34 CallPalProcStatic (
  35   IN      UINT64                    Arg1,
  36   IN      UINT64                    Arg2,
  37   IN      UINT64                    Arg3,
  38   IN      UINT64                    Arg4
  39   );
  40
  41 /**
  42   Stalls the CPU for at least the given number of microseconds.
  43
  44   Stalls the CPU for the number of microseconds specified by MicroSeconds.
  45
  46   @param  MicroSeconds  The minimum number of microseconds to delay.
  47
  48   @return The ticks delayed actually.
  49
  50 **/
  51 UINTN
  52 EFIAPI
  53 MicroSecondDelay (
  54   IN      UINTN                     MicroSeconds
  55   )
  56 {
  57   UINT64                            Ticks;
  58   UINT64                            Delay;
  59
  60   Ticks = GetPerformanceCounter ();
  61   Delay = GetPerformanceCounterProperties (NULL, NULL) * MicroSeconds / 1000000;
  62   while (Ticks + Delay < GetPerformanceCounter ());
  63   return (UINTN)Delay;
  64 }
  65
  66 /**
  67   Stalls the CPU for at least the given number of nanoseconds.
  68
  69   Stalls the CPU for the number of nanoseconds specified by NanoSeconds.
  70
  71   @param  NanoSeconds The minimum number of nanoseconds to delay.
  72
  73   @return The ticks delayed actually.
  74
  75 **/
  76 UINTN
  77 EFIAPI
  78 NanoSecondDelay (
  79   IN      UINTN                     NanoSeconds
  80   )
  81 {
  82   UINT64                            Ticks;
  83   UINT64                            Delay;
  84
  85   Ticks = GetPerformanceCounter ();
  86   Delay = GetPerformanceCounterProperties (NULL, NULL) * NanoSeconds / 1000000000;
  87   while (Ticks + Delay < GetPerformanceCounter ());
  88   return (UINTN)Delay;
  89 }
  90
  91 /**
  92   Retrieves the current value of a 64-bit free running performance counter.
  93
  94   Retrieves the current value of a 64-bit free running performance counter. The
  95   counter can either count up by 1 or count down by 1. If the physical
  96   performance counter counts by a larger increment, then the counter values
  97   must be translated. The properties of the counter can be retrieved from
  98   GetPerformanceCounterProperties().
  99
 100   @return The current value of the free running performance counter.
 101
 102 **/
 103 UINT64
 104 EFIAPI
 105 GetPerformanceCounter (
 106   VOID
 107   )
 108 {
 109   return ReadItc ();
 110 }
 111
 112 /**
 113   Retrieves the 64-bit frequency in Hz and the range of performance counter
 114   values.
 115
 116   If StartValue is not NULL, then the value that the performance counter starts
 117   with immediately after is it rolls over is returned in StartValue. If
 118   EndValue is not NULL, then the value that the performance counter end with
 119   immediately before it rolls over is returned in EndValue. The 64-bit
 120   frequency of the performance counter in Hz is always returned. If StartValue
 121   is less than EndValue, then the performance counter counts up. If StartValue
 122   is greater than EndValue, then the performance counter counts down. For
 123   example, a 64-bit free running counter that counts up would have a StartValue
 124   of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter
 125   that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0.
 126
 127   @param  StartValue  The value the performance counter starts with when it
 128                       rolls over.
 129   @param  EndValue    The value that the performance counter ends with before
 130                       it rolls over.
 131
 132   @return The frequency in Hz.
 133
 134 **/
 135 UINT64
 136 EFIAPI
 137 GetPerformanceCounterProperties (
 138   IN      UINT64                    *StartValue,
 139   IN      UINT64                    *EndValue
 140   )
 141 {
 142   PAL_PROC_RETURN                   PalRet;
 143   UINT64                            BaseFrequence;
 144
 145   PalRet = CallPalProcStatic (13, 0, 0, 0);
 146   ASSERT (PalRet.Status == 0);
 147   BaseFrequence = PalRet.r9;
 148
 149   PalRet = CallPalProcStatic (14, 0, 0, 0);
 150   ASSERT (PalRet.Status == 0);
 151
 152   *StartValue = 0;
 153   *EndValue = (UINT64)(-1);
 154   return BaseFrequence * (PalRet.r11 >> 32) / (UINT32)PalRet.r11;
 155 }