MdeModulePkg/Universal/Metronome/Metronome.h

/** @file
  Include file of Metronome driver.

Copyright (c) 2008, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution.  The full text of the license may be found at
http://opensource.org/licenses/bsd-license.php

THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

**/

#ifndef _METRONOME_H_
#define _METRONOME_H_

#include <PiDxe.h>
#include <Protocol/Metronome.h>
#include <Library/UefiBootServicesTableLib.h>
#include <Library/TimerLib.h>
#include <Library/DebugLib.h>
#include <Library/UefiDriverEntryPoint.h>

/**
  Waits for the specified number of ticks.
  
  This function implements EFI_METRONOME_ARCH_PROTOCOL.WaitForTick().
  The WaitForTick() function waits for the number of ticks specified by 
  TickNumber from a known time source in the platform.  If TickNumber of 
  ticks are detected, then EFI_SUCCESS is returned.  The actual time passed 
  between entry of this function and the first tick is between 0 and 
  TickPeriod 100 nS units.  If you want to guarantee that at least TickPeriod 
  time has elapsed, wait for two ticks.  This function waits for a hardware 
  event to determine when a tick occurs.  It is possible for interrupt 
  processing, or exception processing to interrupt the execution of the 
  WaitForTick() function.  Depending on the hardware source for the ticks, it 
  is possible for a tick to be missed.  This function cannot guarantee that 
  ticks will not be missed.  If a timeout occurs waiting for the specified 
  number of ticks, then EFI_TIMEOUT is returned.

  @param  This             The EFI_METRONOME_ARCH_PROTOCOL instance.
  @param  TickNumber       Number of ticks to wait.

  @retval EFI_SUCCESS      The wait for the number of ticks specified by TickNumber
                           succeeded.
  @retval EFI_TIMEOUT      A timeout occurred waiting for the specified number of ticks.

**/
EFI_STATUS
EFIAPI
WaitForTick (
  IN EFI_METRONOME_ARCH_PROTOCOL  *This,
  IN UINT32                       TickNumber
  );

#endif