MdeModulePkg: Replace BSD License with BSD+Patent License

[mirror_edk2.git] / MdeModulePkg / Core / Dxe / Event / Timer.c

/** @file\r
  Core Timer Services\r
\r
Copyright (c) 2006 - 2013, Intel Corporation. All rights reserved.<BR>\r
SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
**/\r
\r
\r
#include "DxeMain.h"\r
#include "Event.h"\r
\r
//\r
// Internal data\r
//\r
\r
LIST_ENTRY       mEfiTimerList = INITIALIZE_LIST_HEAD_VARIABLE (mEfiTimerList);\r
EFI_LOCK         mEfiTimerLock = EFI_INITIALIZE_LOCK_VARIABLE (TPL_HIGH_LEVEL - 1);\r
EFI_EVENT        mEfiCheckTimerEvent = NULL;\r
\r
EFI_LOCK         mEfiSystemTimeLock = EFI_INITIALIZE_LOCK_VARIABLE (TPL_HIGH_LEVEL);\r
UINT64           mEfiSystemTime = 0;\r
\r
//\r
// Timer functions\r
//\r
/**\r
  Inserts the timer event.\r
\r
  @param  Event                  Points to the internal structure of timer event\r
                                 to be installed\r
\r
**/\r
VOID\r
CoreInsertEventTimer (\r
  IN IEVENT   *Event\r
  )\r
{\r
  UINT64          TriggerTime;\r
  LIST_ENTRY      *Link;\r
  IEVENT          *Event2;\r
\r
  ASSERT_LOCKED (&mEfiTimerLock);\r
\r
  //\r
  // Get the timer's trigger time\r
  //\r
  TriggerTime = Event->Timer.TriggerTime;\r
\r
  //\r
  // Insert the timer into the timer database in assending sorted order\r
  //\r
  for (Link = mEfiTimerList.ForwardLink; Link != &mEfiTimerList; Link = Link->ForwardLink) {\r
    Event2 = CR (Link, IEVENT, Timer.Link, EVENT_SIGNATURE);\r
\r
    if (Event2->Timer.TriggerTime > TriggerTime) {\r
      break;\r
    }\r
  }\r
\r
  InsertTailList (Link, &Event->Timer.Link);\r
}\r
\r
/**\r
  Returns the current system time.\r
\r
  @return The current system time\r
\r
**/\r
UINT64\r
CoreCurrentSystemTime (\r
  VOID\r
  )\r
{\r
  UINT64          SystemTime;\r
\r
  CoreAcquireLock (&mEfiSystemTimeLock);\r
  SystemTime = mEfiSystemTime;\r
  CoreReleaseLock (&mEfiSystemTimeLock);\r
\r
  return SystemTime;\r
}\r
\r
/**\r
  Checks the sorted timer list against the current system time.\r
  Signals any expired event timer.\r
\r
  @param  CheckEvent             Not used\r
  @param  Context                Not used\r
\r
**/\r
VOID\r
EFIAPI\r
CoreCheckTimers (\r
  IN EFI_EVENT            CheckEvent,\r
  IN VOID                 *Context\r
  )\r
{\r
  UINT64                  SystemTime;\r
  IEVENT                  *Event;\r
\r
  //\r
  // Check the timer database for expired timers\r
  //\r
  CoreAcquireLock (&mEfiTimerLock);\r
  SystemTime = CoreCurrentSystemTime ();\r
\r
  while (!IsListEmpty (&mEfiTimerList)) {\r
    Event = CR (mEfiTimerList.ForwardLink, IEVENT, Timer.Link, EVENT_SIGNATURE);\r
\r
    //\r
    // If this timer is not expired, then we're done\r
    //\r
    if (Event->Timer.TriggerTime > SystemTime) {\r
      break;\r
    }\r
\r
    //\r
    // Remove this timer from the timer queue\r
    //\r
\r
    RemoveEntryList (&Event->Timer.Link);\r
    Event->Timer.Link.ForwardLink = NULL;\r
\r
    //\r
    // Signal it\r
    //\r
    CoreSignalEvent (Event);\r
\r
    //\r
    // If this is a periodic timer, set it\r
    //\r
    if (Event->Timer.Period != 0) {\r
      //\r
      // Compute the timers new trigger time\r
      //\r
      Event->Timer.TriggerTime = Event->Timer.TriggerTime + Event->Timer.Period;\r
\r
      //\r
      // If that's before now, then reset the timer to start from now\r
      //\r
      if (Event->Timer.TriggerTime <= SystemTime) {\r
        Event->Timer.TriggerTime = SystemTime;\r
        CoreSignalEvent (mEfiCheckTimerEvent);\r
      }\r
\r
      //\r
      // Add the timer\r
      //\r
      CoreInsertEventTimer (Event);\r
    }\r
  }\r
\r
  CoreReleaseLock (&mEfiTimerLock);\r
}\r
\r
\r
/**\r
  Initializes timer support.\r
\r
**/\r
VOID\r
CoreInitializeTimer (\r
  VOID\r
  )\r
{\r
  EFI_STATUS  Status;\r
\r
  Status = CoreCreateEventInternal (\r
             EVT_NOTIFY_SIGNAL,\r
             TPL_HIGH_LEVEL - 1,\r
             CoreCheckTimers,\r
             NULL,\r
             NULL,\r
             &mEfiCheckTimerEvent\r
             );\r
  ASSERT_EFI_ERROR (Status);\r
}\r
\r
\r
/**\r
  Called by the platform code to process a tick.\r
\r
  @param  Duration               The number of 100ns elapsed since the last call\r
                                 to TimerTick\r
\r
**/\r
VOID\r
EFIAPI\r
CoreTimerTick (\r
  IN UINT64   Duration\r
  )\r
{\r
  IEVENT          *Event;\r
\r
  //\r
  // Check runtiem flag in case there are ticks while exiting boot services\r
  //\r
  CoreAcquireLock (&mEfiSystemTimeLock);\r
\r
  //\r
  // Update the system time\r
  //\r
  mEfiSystemTime += Duration;\r
\r
  //\r
  // If the head of the list is expired, fire the timer event\r
  // to process it\r
  //\r
  if (!IsListEmpty (&mEfiTimerList)) {\r
    Event = CR (mEfiTimerList.ForwardLink, IEVENT, Timer.Link, EVENT_SIGNATURE);\r
\r
    if (Event->Timer.TriggerTime <= mEfiSystemTime) {\r
      CoreSignalEvent (mEfiCheckTimerEvent);\r
    }\r
  }\r
\r
  CoreReleaseLock (&mEfiSystemTimeLock);\r
}\r
\r
\r
\r
/**\r
  Sets the type of timer and the trigger time for a timer event.\r
\r
  @param  UserEvent              The timer event that is to be signaled at the\r
                                 specified time\r
  @param  Type                   The type of time that is specified in\r
                                 TriggerTime\r
  @param  TriggerTime            The number of 100ns units until the timer\r
                                 expires\r
\r
  @retval EFI_SUCCESS            The event has been set to be signaled at the\r
                                 requested time\r
  @retval EFI_INVALID_PARAMETER  Event or Type is not valid\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
CoreSetTimer (\r
  IN EFI_EVENT            UserEvent,\r
  IN EFI_TIMER_DELAY      Type,\r
  IN UINT64               TriggerTime\r
  )\r
{\r
  IEVENT      *Event;\r
\r
  Event = UserEvent;\r
\r
  if (Event == NULL) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  if (Event->Signature != EVENT_SIGNATURE) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  if ((UINT32)Type > TimerRelative  || (Event->Type & EVT_TIMER) == 0) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  CoreAcquireLock (&mEfiTimerLock);\r
\r
  //\r
  // If the timer is queued to the timer database, remove it\r
  //\r
  if (Event->Timer.Link.ForwardLink != NULL) {\r
    RemoveEntryList (&Event->Timer.Link);\r
    Event->Timer.Link.ForwardLink = NULL;\r
  }\r
\r
  Event->Timer.TriggerTime = 0;\r
  Event->Timer.Period = 0;\r
\r
  if (Type != TimerCancel) {\r
\r
    if (Type == TimerPeriodic) {\r
      if (TriggerTime == 0) {\r
        gTimer->GetTimerPeriod (gTimer, &TriggerTime);\r
      }\r
      Event->Timer.Period = TriggerTime;\r
    }\r
\r
    Event->Timer.TriggerTime = CoreCurrentSystemTime () + TriggerTime;\r
    CoreInsertEventTimer (Event);\r
\r
    if (TriggerTime == 0) {\r
      CoreSignalEvent (mEfiCheckTimerEvent);\r
    }\r
  }\r
\r
  CoreReleaseLock (&mEfiTimerLock);\r
\r
  return EFI_SUCCESS;\r
}\r