audk/MdeModulePkg/Universal/WatchDogTimerDxe/WatchDogTimer.c

298 lines
8.1 KiB
C

/*++
Copyright (c) 2006, 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.
Module Name:
WatchDogTimer.c
Abstract:
Generic watchdog timer implemenetation using EFI APIs
Revision History
--*/
#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;
//
// Worker Functions
//
STATIC
VOID
EFIAPI
WatchdogTimerDriverExpires (
IN EFI_EVENT Timer,
IN VOID *Context
)
/*++
Routine Description:
Notification function that is called if the watchdog timer is fired. 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.
Arguments:
Timer - The one-shot timer event that was signaled when the watchdog timer
expired.
Context - The context that was registered when the event Timer was created.
Returns:
None.
--*/
{
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);
}
EFI_STATUS
EFIAPI
WatchdogTimerDriverRegisterHandler (
IN EFI_WATCHDOG_TIMER_ARCH_PROTOCOL *This,
IN EFI_WATCHDOG_TIMER_NOTIFY NotifyFunction
)
/*++
Routine Description:
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.
Arguments:
This - The EFI_WATCHDOG_TIMER_ARCH_PROTOCOL instance.
NotifyFunction - The function to call when the watchdog timer fires. If this
is NULL, then the handler will be unregistered.
Returns:
EFI_SUCCESS - The watchdog timer handler was registered or
unregistered.
EFI_ALREADY_STARTED - NotifyFunction is not NULL, and a handler is already
registered.
EFI_INVALID_PARAMETER - NotifyFunction is NULL, and a handler was not
previously registered.
--*/
{
if (NotifyFunction == NULL && mWatchdogTimerNotifyFunction == NULL) {
return EFI_INVALID_PARAMETER;
}
if (NotifyFunction != NULL && mWatchdogTimerNotifyFunction != NULL) {
return EFI_ALREADY_STARTED;
}
mWatchdogTimerNotifyFunction = NotifyFunction;
return EFI_SUCCESS;
}
EFI_STATUS
EFIAPI
WatchdogTimerDriverSetTimerPeriod (
IN EFI_WATCHDOG_TIMER_ARCH_PROTOCOL *This,
IN UINT64 TimerPeriod
)
/*++
Routine Description:
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.
Arguments:
This - The EFI_WATCHDOG_TIMER_ARCH_PROTOCOL instance.
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.
Returns:
EFI_SUCCESS - The watchdog timer has been programmed to fire in Time
100 nS units.
EFI_DEVICE_ERROR - A watchdog timer could not be programmed due to a device
error.
--*/
{
mWatchdogTimerPeriod = TimerPeriod;
return gBS->SetTimer (
mWatchdogTimerEvent,
(mWatchdogTimerPeriod == 0) ? TimerCancel : TimerRelative,
mWatchdogTimerPeriod
);
}
EFI_STATUS
EFIAPI
WatchdogTimerDriverGetTimerPeriod (
IN EFI_WATCHDOG_TIMER_ARCH_PROTOCOL *This,
IN UINT64 *TimerPeriod
)
/*++
Routine Description:
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.
Arguments:
This - The EFI_WATCHDOG_TIMER_ARCH_PROTOCOL instance.
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.
Returns:
EFI_SUCCESS - The amount of time that the system will wait before
firing the watchdog timer was returned in TimerPeriod.
EFI_INVALID_PARAMETER - TimerPeriod is NULL.
--*/
{
if (TimerPeriod == NULL) {
return EFI_INVALID_PARAMETER;
}
*TimerPeriod = mWatchdogTimerPeriod;
return EFI_SUCCESS;
}
EFI_STATUS
EFIAPI
WatchdogTimerDriverInitialize (
IN EFI_HANDLE ImageHandle,
IN EFI_SYSTEM_TABLE *SystemTable
)
/*++
Routine Description:
Initialize the Watchdog Timer Architectural Protocol driver
Arguments:
ImageHandle - ImageHandle of the loaded driver
SystemTable - Pointer to the System Table
Returns:
EFI_SUCCESS - Timer Architectural Protocol created
EFI_OUT_OF_RESOURCES - Not enough resources available to initialize driver.
EFI_DEVICE_ERROR - A device error occured attempting to initialize the driver.
--*/
{
EFI_STATUS Status;
//
// Make sure the Watchdog Timer Architectural Protocol is not already installed in the system
//
ASSERT_PROTOCOL_ALREADY_INSTALLED (NULL, &gEfiWatchdogTimerArchProtocolGuid);
//
// Create the timer event used 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 Status;
}