diff options
Diffstat (limited to 'ArmPlatformPkg/ArmJunoPkg/Drivers/GenericWatchdogDxe/GenericWatchdogDxe.c')
| -rwxr-xr-x | ArmPlatformPkg/ArmJunoPkg/Drivers/GenericWatchdogDxe/GenericWatchdogDxe.c | 354 |
1 files changed, 354 insertions, 0 deletions
diff --git a/ArmPlatformPkg/ArmJunoPkg/Drivers/GenericWatchdogDxe/GenericWatchdogDxe.c b/ArmPlatformPkg/ArmJunoPkg/Drivers/GenericWatchdogDxe/GenericWatchdogDxe.c new file mode 100755 index 000000000..827d27e2c --- /dev/null +++ b/ArmPlatformPkg/ArmJunoPkg/Drivers/GenericWatchdogDxe/GenericWatchdogDxe.c @@ -0,0 +1,354 @@ +/** @file
+*
+* Copyright (c) 2013-2014, ARM Limited. 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 <PiDxe.h>
+
+#include <Library/BaseLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/DebugLib.h>
+#include <Library/IoLib.h>
+#include <Library/PcdLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiRuntimeServicesTableLib.h>
+#include <Library/UefiLib.h>
+#include <Library/ArmGenericTimerCounterLib.h>
+
+#include <Protocol/WatchdogTimer.h>
+#include <Protocol/HardwareInterrupt.h>
+
+#include <Drivers/GenericWatchdog.h>
+
+// The number of 100ns periods (the unit of time passed to these functions)
+// in a second
+#define TIME_UNITS_PER_SECOND 10000000
+
+// Tick frequency of the generic timer that is the basis of the generic watchdog
+UINTN mTimerFrequencyHz = 0;
+
+// In cases where the compare register was set manually, information about
+// how long the watchdog was asked to wait cannot be retrieved from hardware.
+// It is therefore stored here. 0 means the timer is not running.
+UINT64 mNumTimerTicks = 0;
+
+EFI_HARDWARE_INTERRUPT_PROTOCOL *mInterruptProtocol;
+
+EFI_STATUS
+WatchdogWriteOffsetRegister (
+ UINT32 Value
+ )
+{
+ return MmioWrite32 (GENERIC_WDOG_OFFSET_REG, Value);
+}
+
+EFI_STATUS
+WatchdogWriteCompareRegister (
+ UINT64 Value
+ )
+{
+ return MmioWrite64 (GENERIC_WDOG_COMPARE_VALUE_REG, Value);
+}
+
+EFI_STATUS
+WatchdogEnable (
+ VOID
+ )
+{
+ return MmioWrite32 (GENERIC_WDOG_CONTROL_STATUS_REG, GENERIC_WDOG_ENABLED);
+}
+
+EFI_STATUS
+WatchdogDisable (
+ VOID
+ )
+{
+ return MmioWrite32 (GENERIC_WDOG_CONTROL_STATUS_REG, GENERIC_WDOG_DISABLED);
+}
+
+/**
+ On exiting boot services we must make sure the Watchdog Timer
+ is stopped.
+**/
+VOID
+EFIAPI
+WatchdogExitBootServicesEvent (
+ IN EFI_EVENT Event,
+ IN VOID *Context
+ )
+{
+ WatchdogDisable ();
+ mNumTimerTicks = 0;
+}
+
+/*
+ This function is called when the watchdog's first signal (WS0) goes high.
+ It uses the ResetSystem Runtime Service to reset the board.
+*/
+VOID
+EFIAPI
+WatchdogInterruptHandler (
+ IN HARDWARE_INTERRUPT_SOURCE Source,
+ IN EFI_SYSTEM_CONTEXT SystemContext
+ )
+{
+ STATIC CONST CHAR16 ResetString[] = L"The generic watchdog timer ran out.";
+
+ WatchdogDisable ();
+
+ mInterruptProtocol->EndOfInterrupt (mInterruptProtocol, Source);
+
+ gRT->ResetSystem (
+ EfiResetCold,
+ EFI_TIMEOUT,
+ StrSize (ResetString),
+ &ResetString
+ );
+
+ // If we got here then the reset didn't work
+ ASSERT (FALSE);
+}
+
+/**
+ This function registers the handler NotifyFunction so it is called every time
+ the watchdog timer expires. It also passes the amount of time since the last
+ handler call to the NotifyFunction.
+ If NotifyFunction is not NULL and a handler is not already registered,
+ then the new handler is registered and EFI_SUCCESS is returned.
+ If NotifyFunction is NULL, and a handler is already registered,
+ then that handler is unregistered.
+ 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 unregister a handler when a handler is not registered,
+ then EFI_INVALID_PARAMETER is returned.
+
+ @param This The EFI_TIMER_ARCH_PROTOCOL instance.
+ @param NotifyFunction The function to call when a timer interrupt fires.
+ This function executes at TPL_HIGH_LEVEL. The DXE
+ Core will register a handler for the timer interrupt,
+ so it can know how much time has passed. This
+ information is used to signal timer based events.
+ NULL will unregister the handler.
+
+ @retval EFI_SUCCESS The watchdog timer handler was registered.
+ @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
+WatchdogRegisterHandler (
+ IN CONST EFI_WATCHDOG_TIMER_ARCH_PROTOCOL *This,
+ IN EFI_WATCHDOG_TIMER_NOTIFY NotifyFunction
+ )
+{
+ // ERROR: This function is not supported.
+ // The watchdog will reset the board
+ return EFI_UNSUPPORTED;
+}
+
+/**
+ 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
+WatchdogSetTimerPeriod (
+ IN CONST EFI_WATCHDOG_TIMER_ARCH_PROTOCOL *This,
+ IN UINT64 TimerPeriod // In 100ns units
+ )
+{
+ UINTN TimerVal;
+ EFI_STATUS Status;
+
+ // if TimerPerdiod is 0, this is a request to stop the watchdog.
+ if (TimerPeriod == 0) {
+ mNumTimerTicks = 0;
+ return WatchdogDisable ();
+ }
+
+ // Work out how many timer ticks will equate to TimerPeriod
+ mNumTimerTicks = (mTimerFrequencyHz * TimerPeriod) / TIME_UNITS_PER_SECOND;
+
+ //
+ // If the number of required ticks is greater than the max number the
+ // watchdog's offset register (WOR) can hold, we need to manually compute and
+ // set the compare register (WCV)
+ //
+ if (mNumTimerTicks > MAX_UINT32) {
+ //
+ // We need to enable the watchdog *before* writing to the compare register,
+ // because enabling the watchdog causes an "explicit refresh", which
+ // clobbers the compare register (WCV). In order to make sure this doesn't
+ // trigger an interrupt, set the offset to max.
+ //
+ Status = WatchdogWriteOffsetRegister (MAX_UINT32);
+ if (EFI_ERROR (Status)) {
+ return Status;
+ }
+ WatchdogEnable ();
+ TimerVal = ArmGenericTimerGetTimerVal ();
+ Status = WatchdogWriteCompareRegister (TimerVal + mNumTimerTicks);
+ } else {
+ Status = WatchdogWriteOffsetRegister ((UINT32)mNumTimerTicks);
+ WatchdogEnable ();
+ }
+
+ return Status;
+}
+
+/**
+ This function retrieves the period of timer interrupts in 100 ns units,
+ returns that value in TimerPeriod, and returns EFI_SUCCESS. If TimerPeriod
+ is NULL, then EFI_INVALID_PARAMETER is returned. If a TimerPeriod of 0 is
+ returned, then the timer is currently disabled.
+
+ @param This The EFI_TIMER_ARCH_PROTOCOL instance.
+ @param TimerPeriod A pointer to the timer period to retrieve in 100
+ ns units. If 0 is returned, then the timer is
+ currently disabled.
+
+
+ @retval EFI_SUCCESS The timer period was returned in TimerPeriod.
+ @retval EFI_INVALID_PARAMETER TimerPeriod is NULL.
+
+**/
+EFI_STATUS
+EFIAPI
+WatchdogGetTimerPeriod (
+ IN CONST EFI_WATCHDOG_TIMER_ARCH_PROTOCOL *This,
+ OUT UINT64 *TimerPeriod
+ )
+{
+ if (TimerPeriod == NULL) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ *TimerPeriod = ((TIME_UNITS_PER_SECOND / mTimerFrequencyHz) * mNumTimerTicks);
+
+ return EFI_SUCCESS;
+}
+
+/**
+ Interface structure for the Watchdog Architectural Protocol.
+
+ @par Protocol Description:
+ This protocol provides a service to set the amount of time to wait
+ before firing the watchdog timer, and it also provides a service to
+ register a handler that is invoked when the watchdog timer fires.
+
+ @par When the watchdog timer fires, control will be passed to a handler
+ if one has been registered. If no handler has been registered,
+ or the registered handler returns, then the system will be
+ reset by calling the Runtime Service ResetSystem().
+
+ @param RegisterHandler
+ Registers a handler that will be called each time the
+ watchdogtimer interrupt fires. TimerPeriod defines the minimum
+ time between timer interrupts, so TimerPeriod will also
+ be the minimum time between calls to the registered
+ handler.
+ NOTE: If the watchdog resets the system in hardware, then
+ this function will not have any chance of executing.
+
+ @param SetTimerPeriod
+ Sets the period of the timer interrupt in 100 nS units.
+ This function is optional, and may return EFI_UNSUPPORTED.
+ If this function is supported, then the timer period will
+ be rounded up to the nearest supported timer period.
+
+ @param GetTimerPeriod
+ Retrieves the period of the timer interrupt in 100 nS units.
+
+**/
+EFI_WATCHDOG_TIMER_ARCH_PROTOCOL gWatchdogTimer = {
+ (EFI_WATCHDOG_TIMER_REGISTER_HANDLER) WatchdogRegisterHandler,
+ (EFI_WATCHDOG_TIMER_SET_TIMER_PERIOD) WatchdogSetTimerPeriod,
+ (EFI_WATCHDOG_TIMER_GET_TIMER_PERIOD) WatchdogGetTimerPeriod
+};
+
+EFI_EVENT EfiExitBootServicesEvent = (EFI_EVENT)NULL;
+
+EFI_STATUS
+EFIAPI
+GenericWatchdogEntry (
+ IN EFI_HANDLE ImageHandle,
+ IN EFI_SYSTEM_TABLE *SystemTable
+ )
+{
+ EFI_STATUS Status;
+ EFI_HANDLE Handle;
+
+ //
+ // Make sure the Watchdog Timer Architectural Protocol has not been installed
+ // in the system yet.
+ // This will avoid conflicts with the universal watchdog
+ //
+ ASSERT_PROTOCOL_ALREADY_INSTALLED (NULL, &gEfiWatchdogTimerArchProtocolGuid);
+
+ mTimerFrequencyHz = ArmGenericTimerGetTimerFreq ();
+ ASSERT (mTimerFrequencyHz != 0);
+
+ // Register for an ExitBootServicesEvent
+ Status = gBS->CreateEvent (
+ EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_NOTIFY,
+ WatchdogExitBootServicesEvent, NULL, &EfiExitBootServicesEvent
+ );
+ if (!EFI_ERROR (Status)) {
+ // Install interrupt handler
+ Status = gBS->LocateProtocol (
+ &gHardwareInterruptProtocolGuid,
+ NULL,
+ (VOID **)&mInterruptProtocol
+ );
+ if (!EFI_ERROR (Status)) {
+ Status = mInterruptProtocol->RegisterInterruptSource (
+ mInterruptProtocol,
+ FixedPcdGet32 (PcdGenericWatchdogEl2IntrNum),
+ WatchdogInterruptHandler
+ );
+ if (!EFI_ERROR (Status)) {
+ // Install the Timer Architectural Protocol onto a new handle
+ Handle = NULL;
+ Status = gBS->InstallMultipleProtocolInterfaces (
+ &Handle,
+ &gEfiWatchdogTimerArchProtocolGuid, &gWatchdogTimer,
+ NULL
+ );
+ }
+ }
+ }
+
+ if (EFI_ERROR (Status)) {
+ // The watchdog failed to initialize
+ ASSERT (FALSE);
+ }
+
+ mNumTimerTicks = 0;
+ WatchdogDisable ();
+
+ return Status;
+}
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