/** @file | |
Implementation of Watchdog Timer Architectural Protocol using UEFI APIs. | |
Copyright (c) 2006 - 2008, Intel Corporation | |
All rights reserved. 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. | |
**/ | |
#include "WatchdogTimer.h" | |
// | |
// Handle for the Watchdog Timer Architectural Protocol instance produced by this driver | |
// | |
EFI_HANDLE mWatchdogTimerHandle = NULL; | |
// | |
// The Watchdog Timer Architectural Protocol instance produced by this driver | |
// | |
EFI_WATCHDOG_TIMER_ARCH_PROTOCOL mWatchdogTimer = { | |
WatchdogTimerDriverRegisterHandler, | |
WatchdogTimerDriverSetTimerPeriod, | |
WatchdogTimerDriverGetTimerPeriod | |
}; | |
// | |
// The watchdog timer period in 100 ns units | |
// | |
UINT64 mWatchdogTimerPeriod = 0; | |
// | |
// The notification function to call if the watchdig timer fires | |
// | |
EFI_WATCHDOG_TIMER_NOTIFY mWatchdogTimerNotifyFunction = NULL; | |
// | |
// The one-shot timer event that is armed when the watchdog timer is enabled | |
// | |
EFI_EVENT mWatchdogTimerEvent; | |
/** | |
Notification function that is called if the watchdog timer is fired. | |
Notification function for the one-shot timer event that was signaled | |
when the watchdog timer expired. If a handler has been registered with | |
the Watchdog Timer Architectural Protocol, then that handler is called | |
passing in the time period that has passed that cause the watchdog timer | |
to fire. Then, a call to the Runtime Service ResetSystem() is made to | |
reset the platform. | |
@param Timer The one-shot timer event that was signaled when the | |
watchdog timer expired. | |
@param Context The context that was registered when the event Timer was created. | |
**/ | |
VOID | |
EFIAPI | |
WatchdogTimerDriverExpires ( | |
IN EFI_EVENT Timer, | |
IN VOID *Context | |
) | |
{ | |
REPORT_STATUS_CODE (EFI_ERROR_CODE | EFI_ERROR_MINOR, PcdGet32 (PcdStatusCodeValueEfiWatchDogTimerExpired)); | |
// | |
// If a notification function has been registered, then call it | |
// | |
if (mWatchdogTimerNotifyFunction != NULL) { | |
mWatchdogTimerNotifyFunction (mWatchdogTimerPeriod); | |
} | |
// | |
// Reset the platform | |
// | |
gRT->ResetSystem (EfiResetCold, EFI_TIMEOUT, 0, NULL); | |
} | |
/** | |
Registers a handler that is to be invoked when the watchdog timer fires. | |
This function registers a handler that is to be invoked when the watchdog | |
timer fires. By default, the EFI_WATCHDOG_TIMER protocol will call the | |
Runtime Service ResetSystem() when the watchdog timer fires. If a | |
NotifyFunction is registered, then the NotifyFunction will be called before | |
the Runtime Service ResetSystem() is called. If NotifyFunction is NULL, then | |
the watchdog handler is unregistered. If a watchdog handler is registered, | |
then EFI_SUCCESS is returned. If an attempt is made to register a handler | |
when a handler is already registered, then EFI_ALREADY_STARTED is returned. | |
If an attempt is made to uninstall a handler when a handler is not installed, | |
then return EFI_INVALID_PARAMETER. | |
@param This The EFI_WATCHDOG_TIMER_ARCH_PROTOCOL instance. | |
@param NotifyFunction The function to call when the watchdog timer fires. If this | |
is NULL, then the handler will be unregistered. | |
@retval EFI_SUCCESS The watchdog timer handler was registered or unregistered. | |
@retval EFI_ALREADY_STARTED NotifyFunction is not NULL, and a handler is already registered. | |
@retval EFI_INVALID_PARAMETER NotifyFunction is NULL, and a handler was not previously registered. | |
**/ | |
EFI_STATUS | |
EFIAPI | |
WatchdogTimerDriverRegisterHandler ( | |
IN EFI_WATCHDOG_TIMER_ARCH_PROTOCOL *This, | |
IN EFI_WATCHDOG_TIMER_NOTIFY NotifyFunction | |
) | |
{ | |
// | |
// If NotifyFunction is NULL, and a handler was not previously registered, | |
// return EFI_INVALID_PARAMETER. | |
// | |
if (NotifyFunction == NULL && mWatchdogTimerNotifyFunction == NULL) { | |
return EFI_INVALID_PARAMETER; | |
} | |
// | |
// If NotifyFunction is not NULL, and a handler is already registered, | |
// return EFI_ALREADY_STARTED. | |
// | |
if (NotifyFunction != NULL && mWatchdogTimerNotifyFunction != NULL) { | |
return EFI_ALREADY_STARTED; | |
} | |
mWatchdogTimerNotifyFunction = NotifyFunction; | |
return EFI_SUCCESS; | |
} | |
/** | |
Sets the amount of time in the future to fire the watchdog timer. | |
This function sets the amount of time to wait before firing the watchdog | |
timer to TimerPeriod 100 ns units. If TimerPeriod is 0, then the watchdog | |
timer is disabled. | |
@param This The EFI_WATCHDOG_TIMER_ARCH_PROTOCOL instance. | |
@param TimerPeriod The amount of time in 100 ns units to wait before the watchdog | |
timer is fired. If TimerPeriod is zero, then the watchdog | |
timer is disabled. | |
@retval EFI_SUCCESS The watchdog timer has been programmed to fire in Time | |
100 ns units. | |
@retval EFI_DEVICE_ERROR A watchdog timer could not be programmed due to a device | |
error. | |
**/ | |
EFI_STATUS | |
EFIAPI | |
WatchdogTimerDriverSetTimerPeriod ( | |
IN EFI_WATCHDOG_TIMER_ARCH_PROTOCOL *This, | |
IN UINT64 TimerPeriod | |
) | |
{ | |
mWatchdogTimerPeriod = TimerPeriod; | |
return gBS->SetTimer ( | |
mWatchdogTimerEvent, | |
(mWatchdogTimerPeriod == 0) ? TimerCancel : TimerRelative, | |
mWatchdogTimerPeriod | |
); | |
} | |
/** | |
Retrieves the amount of time in 100 ns units that the system will wait before firing the watchdog timer. | |
This function retrieves the amount of time the system will wait before firing | |
the watchdog timer. This period is returned in TimerPeriod, and EFI_SUCCESS | |
is returned. If TimerPeriod is NULL, then EFI_INVALID_PARAMETER is returned. | |
@param This The EFI_WATCHDOG_TIMER_ARCH_PROTOCOL instance. | |
@param TimerPeriod A pointer to the amount of time in 100 ns units that the system | |
will wait before the watchdog timer is fired. If TimerPeriod of | |
zero is returned, then the watchdog timer is disabled. | |
@retval EFI_SUCCESS The amount of time that the system will wait before | |
firing the watchdog timer was returned in TimerPeriod. | |
@retval EFI_INVALID_PARAMETER TimerPeriod is NULL. | |
**/ | |
EFI_STATUS | |
EFIAPI | |
WatchdogTimerDriverGetTimerPeriod ( | |
IN EFI_WATCHDOG_TIMER_ARCH_PROTOCOL *This, | |
IN UINT64 *TimerPeriod | |
) | |
{ | |
if (TimerPeriod == NULL) { | |
return EFI_INVALID_PARAMETER; | |
} | |
*TimerPeriod = mWatchdogTimerPeriod; | |
return EFI_SUCCESS; | |
} | |
/** | |
Entry point of the Watchdog Timer Architectural Protocol driver. | |
@param ImageHandle The image handle of this driver. | |
@param SystemTable The pointer of EFI_SYSTEM_TABLE. | |
@retval EFI_SUCCESS Watchdog Timer Architectural Protocol successfully installed. | |
**/ | |
EFI_STATUS | |
EFIAPI | |
WatchdogTimerDriverInitialize ( | |
IN EFI_HANDLE ImageHandle, | |
IN EFI_SYSTEM_TABLE *SystemTable | |
) | |
{ | |
EFI_STATUS Status; | |
// | |
// Make sure the Watchdog Timer Architectural Protocol has not been installed in the system yet. | |
// | |
ASSERT_PROTOCOL_ALREADY_INSTALLED (NULL, &gEfiWatchdogTimerArchProtocolGuid); | |
// | |
// Create the timer event to implement a simple watchdog timer | |
// | |
Status = gBS->CreateEvent ( | |
EVT_TIMER | EVT_NOTIFY_SIGNAL, | |
TPL_NOTIFY, | |
WatchdogTimerDriverExpires, | |
NULL, | |
&mWatchdogTimerEvent | |
); | |
ASSERT_EFI_ERROR (Status); | |
// | |
// Install the Watchdog Timer Arch Protocol onto a new handle | |
// | |
Status = gBS->InstallMultipleProtocolInterfaces ( | |
&mWatchdogTimerHandle, | |
&gEfiWatchdogTimerArchProtocolGuid, | |
&mWatchdogTimer, | |
NULL | |
); | |
ASSERT_EFI_ERROR (Status); | |
return EFI_SUCCESS; | |
} |