Omap35xxPkg/Library/Omap35xxTimerLib/TimerLib.c

   1 /** @file
   2
   3   Copyright (c) 2008-2009, Apple Inc. All rights reserved.
   4
   5   All rights reserved. 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 <Base.h>
  16
  17 #include <Library/BaseLib.h>
  18 #include <Library/TimerLib.h>
  19 #include <Library/DebugLib.h>
  20 #include <Library/PcdLib.h>
  21 #include <Library/IoLib.h>
  22 #include <Library/OmapLib.h>
  23
  24 #include <Omap3530/Omap3530.h>
  25
  26 UINTN
  27 EFIAPI
  28 MicroSecondDelay (
  29   IN  UINTN MicroSeconds
  30   )
  31 {
  32   UINT64  NanoSeconds;
  33
  34   NanoSeconds = MultU64x32(MicroSeconds, 1000);
  35
  36   while (NanoSeconds > (UINTN)-1) {
  37     NanoSecondDelay((UINTN)-1);
  38     NanoSeconds -= (UINTN)-1;
  39   }
  40
  41   NanoSecondDelay(NanoSeconds);
  42
  43   return MicroSeconds;
  44 }
  45
  46 UINTN
  47 EFIAPI
  48 NanoSecondDelay (
  49   IN  UINTN NanoSeconds
  50   )
  51 {
  52   UINT32  Delay;
  53   UINT32  StartTime;
  54   UINT32  CurrentTime;
  55   UINT32  ElapsedTime;
  56   UINT32  TimerCountRegister;
  57
  58   Delay = (NanoSeconds / PcdGet32(PcdEmbeddedFdPerformanceCounterPeriodInNanoseconds)) + 1;
  59
  60   TimerCountRegister = TimerBase(PcdGet32(PcdOmap35xxFreeTimer)) + GPTIMER_TCRR;
  61
  62   StartTime = MmioRead32 (TimerCountRegister);
  63
  64   do
  65   {
  66     CurrentTime = MmioRead32 (TimerCountRegister);
  67     ElapsedTime = CurrentTime - StartTime;
  68   } while (ElapsedTime < Delay);
  69
  70   NanoSeconds = ElapsedTime * PcdGet32(PcdEmbeddedFdPerformanceCounterPeriodInNanoseconds);
  71
  72   return NanoSeconds;
  73 }
  74
  75 UINT64
  76 EFIAPI
  77 GetPerformanceCounter (
  78   VOID
  79   )
  80 {
  81   return (UINT64)MmioRead32 (TimerBase(PcdGet32(PcdOmap35xxFreeTimer)) + GPTIMER_TCRR);
  82 }
  83
  84 UINT64
  85 EFIAPI
  86 GetPerformanceCounterProperties (
  87   OUT UINT64  *StartValue,  OPTIONAL
  88   OUT UINT64  *EndValue     OPTIONAL
  89   )
  90 {
  91   if (StartValue != NULL) {
  92     // Timer starts with the reload value
  93     *StartValue = (UINT64)MmioRead32 (TimerBase(PcdGet32(PcdOmap35xxFreeTimer)) + GPTIMER_TLDR);
  94   }
  95
  96   if (EndValue != NULL) {
  97     // Timer counts up to 0xFFFFFFFF
  98     *EndValue = 0xFFFFFFFF;
  99   }
 100
 101   return PcdGet64(PcdEmbeddedPerformanceCounterFreqencyInHz);
 102 }