A better template, with some build scripts, for ArmEbPkg. New libraries are just...

[mirror_edk2.git] / ArmEbPkg / Library / TimerLib / TimerLib.c

/** @file\r
\r
  Copyright (c) 2008 - 2010, Apple Inc. All rights reserved.<BR>\r
  \r
  This program and the accompanying materials\r
  are licensed and made available under the terms and conditions of the BSD License\r
  which accompanies this distribution.  The full text of the license may be found at\r
  http://opensource.org/licenses/bsd-license.php\r
\r
  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
\r
**/\r
\r
#include <Base.h>\r
\r
#include <Library/BaseLib.h>\r
#include <Library/TimerLib.h>\r
#include <Library/DebugLib.h>\r
#include <Library/PcdLib.h>\r
#include <Library/IoLib.h>\r
\r
\r
UINTN\r
EFIAPI\r
MicroSecondDelay (\r
  IN  UINTN MicroSeconds\r
  )\r
{\r
  UINT64  NanoSeconds;\r
  \r
  NanoSeconds = MultU64x32 (MicroSeconds, 1000);\r
\r
  while (NanoSeconds > (UINTN)-1) { \r
    NanoSecondDelay((UINTN)-1);\r
    NanoSeconds -= (UINTN)-1;\r
  }\r
\r
  NanoSecondDelay (NanoSeconds);\r
\r
  return MicroSeconds;\r
}\r
\r
UINTN\r
EFIAPI\r
NanoSecondDelay (\r
  IN  UINTN NanoSeconds\r
  )\r
{\r
  UINT32  Delay;\r
  UINT32  StartTime;\r
  UINT32  CurrentTime;\r
  UINT32  ElapsedTime;\r
\r
 \r
  Delay = (NanoSeconds / PcdGet32(PcdEmbeddedPerformanceCounterPeriodInNanoseconds)) + 1;\r
\r
  StartTime = MmioRead32 (0);\r
  do \r
  {\r
    CurrentTime = 0ULL;\r
    ElapsedTime = CurrentTime - StartTime;\r
  } while (ElapsedTime < Delay);\r
\r
  NanoSeconds = ElapsedTime * PcdGet32 (PcdEmbeddedPerformanceCounterPeriodInNanoseconds);\r
\r
  return NanoSeconds;\r
}\r
\r
UINT64\r
EFIAPI\r
GetPerformanceCounter (\r
  VOID\r
  )\r
{ \r
  return (UINT64)0ULL;\r
}\r
\r
UINT64\r
EFIAPI\r
GetPerformanceCounterProperties (\r
  OUT UINT64  *StartValue,  OPTIONAL\r
  OUT UINT64  *EndValue     OPTIONAL\r
  )\r
{\r
  if (StartValue != NULL) {\r
    // Timer starts with the reload value\r
    *StartValue = (UINT64)0ULL;\r
  }\r
  \r
  if (EndValue != NULL) {\r
    // Timer counts up to 0xFFFFFFFF\r
    *EndValue = 0xFFFFFFFF;\r
  }\r
  \r
  return PcdGet64(PcdEmbeddedPerformanceCounterFrequencyInHz);\r
}\r