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 PalCallStatic (
  35   IN      CONST VOID                *PalEntryPoint,
  36   IN      UINT64                    Arg1,
  37   IN      UINT64                    Arg2,
  38   IN      UINT64                    Arg3,
  39   IN      UINT64                    Arg4
  40   );
  41
  42 /**
  43   Stalls the CPU for at least the given number of microseconds.
  44
  45   Stalls the CPU for the number of microseconds specified by MicroSeconds.
  46
  47   @param  MicroSeconds  The minimum number of microseconds to delay.
  48
  49   @return The ticks delayed actually.
  50
  51 **/
  52 UINTN
  53 EFIAPI
  54 MicroSecondDelay (
  55   IN      UINTN                     MicroSeconds
  56   )
  57 {
  58   UINT64                            Ticks;
  59   UINT64                            Delay;
  60
  61   Ticks = GetPerformanceCounter ();
  62   Delay = GetPerformanceCounterProperties (NULL, NULL) * MicroSeconds / 1000000;
  63   while (Ticks + Delay >= GetPerformanceCounter ());
  64   return (UINTN)Delay;
  65 }
  66
  67 /**
  68   Stalls the CPU for at least the given number of nanoseconds.
  69
  70   Stalls the CPU for the number of nanoseconds specified by NanoSeconds.
  71
  72   @param  NanoSeconds The minimum number of nanoseconds to delay.
  73
  74   @return The ticks delayed actually.
  75
  76 **/
  77 UINTN
  78 EFIAPI
  79 NanoSecondDelay (
  80   IN      UINTN                     NanoSeconds
  81   )
  82 {
  83   UINT64                            Ticks;
  84   UINT64                            Delay;
  85
  86   Ticks = GetPerformanceCounter ();
  87   Delay = GetPerformanceCounterProperties (NULL, NULL) * NanoSeconds / 1000000000;
  88   while (Ticks + Delay >= GetPerformanceCounter ());
  89   return (UINTN)Delay;
  90 }
  91
  92 /**
  93   Retrieves the current value of a 64-bit free running performance counter.
  94
  95   Retrieves the current value of a 64-bit free running performance counter. The
  96   counter can either count up by 1 or count down by 1. If the physical
  97   performance counter counts by a larger increment, then the counter values
  98   must be translated. The properties of the counter can be retrieved from
  99   GetPerformanceCounterProperties().
 100
 101   @return The current value of the free running performance counter.
 102
 103 **/
 104 UINT64
 105 EFIAPI
 106 GetPerformanceCounter (
 107   VOID
 108   )
 109 {
 110   return ReadItc ();
 111 }
 112
 113 /**
 114   Retrieves the 64-bit frequency in Hz and the range of performance counter
 115   values.
 116
 117   If StartValue is not NULL, then the value that the performance counter starts
 118   with immediately after is it rolls over is returned in StartValue. If
 119   EndValue is not NULL, then the value that the performance counter end with
 120   immediately before it rolls over is returned in EndValue. The 64-bit
 121   frequency of the performance counter in Hz is always returned. If StartValue
 122   is less than EndValue, then the performance counter counts up. If StartValue
 123   is greater than EndValue, then the performance counter counts down. For
 124   example, a 64-bit free running counter that counts up would have a StartValue
 125   of 0 and an EndValue of 0xFFFFFFFFFFFFFFFF. A 24-bit free running counter
 126   that counts down would have a StartValue of 0xFFFFFF and an EndValue of 0.
 127
 128   @param  StartValue  The value the performance counter starts with when it
 129                       rolls over.
 130   @param  EndValue    The value that the performance counter ends with before
 131                       it rolls over.
 132
 133   @return The frequency in Hz.
 134
 135 **/
 136 UINT64
 137 EFIAPI
 138 GetPerformanceCounterProperties (
 139   IN      UINT64                    *StartValue,
 140   IN      UINT64                    *EndValue
 141   )
 142 {
 143   PAL_PROC_RETURN                   PalRet;
 144   UINT64                            BaseFrequence;
 145
 146   PalRet = PalCallStatic (NULL, 13, 0, 0, 0);
 147   ASSERT (PalRet.Status == 0);
 148   BaseFrequence = PalRet.r9;
 149
 150   PalRet = PalCallStatic (NULL, 14, 0, 0, 0);
 151   ASSERT (PalRet.Status == 0);
 152
 153   *StartValue = 0;
 154   *EndValue = (UINT64)(-1);
 155   return BaseFrequence * (PalRet.r11 >> 32) / (UINT32)PalRet.r11;
 156 }