mirror of https://github.com/acidanthera/audk.git
389 lines
13 KiB
C
389 lines
13 KiB
C
/** @file
|
|
*
|
|
* Copyright (c) 2011-2013, 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 <Protocol/WatchdogTimer.h>
|
|
|
|
#include "SP805Watchdog.h"
|
|
|
|
EFI_EVENT EfiExitBootServicesEvent = (EFI_EVENT)NULL;
|
|
|
|
/**
|
|
Make sure the SP805 registers are unlocked for writing.
|
|
|
|
Note: The SP805 Watchdog Timer supports locking of its registers,
|
|
i.e. it inhibits all writes to avoid rogue software accidentally
|
|
corrupting their contents.
|
|
**/
|
|
STATIC
|
|
VOID
|
|
SP805Unlock (
|
|
VOID
|
|
)
|
|
{
|
|
if( MmioRead32(SP805_WDOG_LOCK_REG) == SP805_WDOG_LOCK_IS_LOCKED ) {
|
|
MmioWrite32(SP805_WDOG_LOCK_REG, SP805_WDOG_SPECIAL_UNLOCK_CODE);
|
|
}
|
|
}
|
|
|
|
/**
|
|
Make sure the SP805 registers are locked and can not be overwritten.
|
|
|
|
Note: The SP805 Watchdog Timer supports locking of its registers,
|
|
i.e. it inhibits all writes to avoid rogue software accidentally
|
|
corrupting their contents.
|
|
**/
|
|
STATIC
|
|
VOID
|
|
SP805Lock (
|
|
VOID
|
|
)
|
|
{
|
|
if( MmioRead32(SP805_WDOG_LOCK_REG) == SP805_WDOG_LOCK_IS_UNLOCKED ) {
|
|
// To lock it, just write in any number (except the special unlock code).
|
|
MmioWrite32(SP805_WDOG_LOCK_REG, SP805_WDOG_LOCK_IS_LOCKED);
|
|
}
|
|
}
|
|
|
|
/**
|
|
Stop the SP805 watchdog timer from counting down by disabling interrupts.
|
|
**/
|
|
STATIC
|
|
VOID
|
|
SP805Stop (
|
|
VOID
|
|
)
|
|
{
|
|
// Disable interrupts
|
|
if ( (MmioRead32(SP805_WDOG_CONTROL_REG) & SP805_WDOG_CTRL_INTEN) != 0 ) {
|
|
MmioAnd32(SP805_WDOG_CONTROL_REG, ~SP805_WDOG_CTRL_INTEN);
|
|
}
|
|
}
|
|
|
|
/**
|
|
Starts the SP805 counting down by enabling interrupts.
|
|
The count down will start from the value stored in the Load register,
|
|
not from the value where it was previously stopped.
|
|
**/
|
|
STATIC
|
|
VOID
|
|
SP805Start (
|
|
VOID
|
|
)
|
|
{
|
|
// Enable interrupts
|
|
if ( (MmioRead32(SP805_WDOG_CONTROL_REG) & SP805_WDOG_CTRL_INTEN) == 0 ) {
|
|
MmioOr32(SP805_WDOG_CONTROL_REG, SP805_WDOG_CTRL_INTEN);
|
|
}
|
|
}
|
|
|
|
/**
|
|
On exiting boot services we must make sure the SP805 Watchdog Timer
|
|
is stopped.
|
|
**/
|
|
VOID
|
|
EFIAPI
|
|
ExitBootServicesEvent (
|
|
IN EFI_EVENT Event,
|
|
IN VOID *Context
|
|
)
|
|
{
|
|
SP805Unlock();
|
|
SP805Stop();
|
|
SP805Lock();
|
|
}
|
|
|
|
/**
|
|
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
|
|
SP805RegisterHandler (
|
|
IN CONST EFI_WATCHDOG_TIMER_ARCH_PROTOCOL *This,
|
|
IN EFI_WATCHDOG_TIMER_NOTIFY NotifyFunction
|
|
)
|
|
{
|
|
// ERROR: This function is not supported.
|
|
// The hardware watchdog will reset the board
|
|
return EFI_INVALID_PARAMETER;
|
|
}
|
|
|
|
/**
|
|
|
|
This function adjusts the period of timer interrupts to the value specified
|
|
by TimerPeriod. If the timer period is updated, then the selected timer
|
|
period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned. If
|
|
the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.
|
|
If an error occurs while attempting to update the timer period, then the
|
|
timer hardware will be put back in its state prior to this call, and
|
|
EFI_DEVICE_ERROR is returned. If TimerPeriod is 0, then the timer interrupt
|
|
is disabled. This is not the same as disabling the CPU's interrupts.
|
|
Instead, it must either turn off the timer hardware, or it must adjust the
|
|
interrupt controller so that a CPU interrupt is not generated when the timer
|
|
interrupt fires.
|
|
|
|
@param This The EFI_TIMER_ARCH_PROTOCOL instance.
|
|
@param TimerPeriod The rate to program the timer interrupt in 100 nS units. If
|
|
the timer hardware is not programmable, then EFI_UNSUPPORTED is
|
|
returned. If the timer is programmable, then the timer period
|
|
will be rounded up to the nearest timer period that is supported
|
|
by the timer hardware. If TimerPeriod is set to 0, then the
|
|
timer interrupts will be disabled.
|
|
|
|
|
|
@retval EFI_SUCCESS The timer period was changed.
|
|
@retval EFI_UNSUPPORTED The platform cannot change the period of the timer interrupt.
|
|
@retval EFI_DEVICE_ERROR The timer period could not be changed due to a device error.
|
|
|
|
**/
|
|
EFI_STATUS
|
|
EFIAPI
|
|
SP805SetTimerPeriod (
|
|
IN CONST EFI_WATCHDOG_TIMER_ARCH_PROTOCOL *This,
|
|
IN UINT64 TimerPeriod // In 100ns units
|
|
)
|
|
{
|
|
EFI_STATUS Status = EFI_SUCCESS;
|
|
UINT64 Ticks64bit;
|
|
|
|
SP805Unlock();
|
|
|
|
if( TimerPeriod == 0 ) {
|
|
// This is a watchdog stop request
|
|
SP805Stop();
|
|
goto EXIT;
|
|
} else {
|
|
// Calculate the Watchdog ticks required for a delay of (TimerTicks * 100) nanoseconds
|
|
// The SP805 will count down to ZERO once, generate an interrupt and
|
|
// then it will again reload the initial value and start again.
|
|
// On the second time when it reaches ZERO, it will actually reset the board.
|
|
// Therefore, we need to load half the required delay.
|
|
//
|
|
// WatchdogTicks = ((TimerPeriod * 100 * SP805_CLOCK_FREQUENCY) / 1GHz) / 2 ;
|
|
//
|
|
// i.e.:
|
|
//
|
|
// WatchdogTicks = (TimerPeriod * SP805_CLOCK_FREQUENCY) / 20 MHz ;
|
|
|
|
Ticks64bit = DivU64x32(MultU64x32(TimerPeriod, (UINTN)PcdGet32(PcdSP805WatchdogClockFrequencyInHz)), 20000000);
|
|
|
|
// The registers in the SP805 are only 32 bits
|
|
if(Ticks64bit > (UINT64)0xFFFFFFFF) {
|
|
// We could load the watchdog with the maximum supported value but
|
|
// if a smaller value was requested, this could have the watchdog
|
|
// triggering before it was intended.
|
|
// Better generate an error to let the caller know.
|
|
Status = EFI_DEVICE_ERROR;
|
|
goto EXIT;
|
|
}
|
|
|
|
// Update the watchdog with a 32-bit value.
|
|
MmioWrite32(SP805_WDOG_LOAD_REG, (UINT32)Ticks64bit);
|
|
|
|
// Start the watchdog
|
|
SP805Start();
|
|
}
|
|
|
|
EXIT:
|
|
// Ensure the watchdog is locked before exiting.
|
|
SP805Lock();
|
|
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
|
|
SP805GetTimerPeriod (
|
|
IN CONST EFI_WATCHDOG_TIMER_ARCH_PROTOCOL *This,
|
|
OUT UINT64 *TimerPeriod
|
|
)
|
|
{
|
|
EFI_STATUS Status = EFI_SUCCESS;
|
|
UINT64 ReturnValue;
|
|
|
|
if (TimerPeriod == NULL) {
|
|
return EFI_INVALID_PARAMETER;
|
|
}
|
|
|
|
// Check if the watchdog is stopped
|
|
if ( (MmioRead32(SP805_WDOG_CONTROL_REG) & SP805_WDOG_CTRL_INTEN) == 0 ) {
|
|
// It is stopped, so return zero.
|
|
ReturnValue = 0;
|
|
} else {
|
|
// Convert the Watchdog ticks into TimerPeriod
|
|
// Ensure 64bit arithmetic throughout because the Watchdog ticks may already
|
|
// be at the maximum 32 bit value and we still need to multiply that by 600.
|
|
ReturnValue = MultU64x32( MmioRead32(SP805_WDOG_LOAD_REG), 600 );
|
|
}
|
|
|
|
*TimerPeriod = ReturnValue;
|
|
|
|
return Status;
|
|
}
|
|
|
|
/**
|
|
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) SP805RegisterHandler,
|
|
(EFI_WATCHDOG_TIMER_SET_TIMER_PERIOD) SP805SetTimerPeriod,
|
|
(EFI_WATCHDOG_TIMER_GET_TIMER_PERIOD) SP805GetTimerPeriod
|
|
};
|
|
|
|
/**
|
|
Initialize the state information for the Watchdog Timer Architectural Protocol.
|
|
|
|
@param ImageHandle of the loaded driver
|
|
@param SystemTable Pointer to the System Table
|
|
|
|
@retval EFI_SUCCESS Protocol registered
|
|
@retval EFI_OUT_OF_RESOURCES Cannot allocate protocol data structure
|
|
@retval EFI_DEVICE_ERROR Hardware problems
|
|
|
|
**/
|
|
EFI_STATUS
|
|
EFIAPI
|
|
SP805Initialize (
|
|
IN EFI_HANDLE ImageHandle,
|
|
IN EFI_SYSTEM_TABLE *SystemTable
|
|
)
|
|
{
|
|
EFI_STATUS Status;
|
|
EFI_HANDLE Handle;
|
|
|
|
// Unlock access to the SP805 registers
|
|
SP805Unlock ();
|
|
|
|
// Stop the watchdog from triggering unexpectedly
|
|
SP805Stop ();
|
|
|
|
// Set the watchdog to reset the board when triggered
|
|
if ((MmioRead32(SP805_WDOG_CONTROL_REG) & SP805_WDOG_CTRL_RESEN) == 0) {
|
|
MmioOr32 (SP805_WDOG_CONTROL_REG, SP805_WDOG_CTRL_RESEN);
|
|
}
|
|
|
|
// Prohibit any rogue access to SP805 registers
|
|
SP805Lock();
|
|
|
|
//
|
|
// 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);
|
|
|
|
// Register for an ExitBootServicesEvent
|
|
Status = gBS->CreateEvent (EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_NOTIFY, ExitBootServicesEvent, NULL, &EfiExitBootServicesEvent);
|
|
if (EFI_ERROR(Status)) {
|
|
Status = EFI_OUT_OF_RESOURCES;
|
|
goto EXIT;
|
|
}
|
|
|
|
// Install the Timer Architectural Protocol onto a new handle
|
|
Handle = NULL;
|
|
Status = gBS->InstallMultipleProtocolInterfaces(
|
|
&Handle,
|
|
&gEfiWatchdogTimerArchProtocolGuid, &gWatchdogTimer,
|
|
NULL
|
|
);
|
|
if (EFI_ERROR(Status)) {
|
|
Status = EFI_OUT_OF_RESOURCES;
|
|
goto EXIT;
|
|
}
|
|
|
|
EXIT:
|
|
if(EFI_ERROR(Status)) {
|
|
// The watchdog failed to initialize
|
|
ASSERT(FALSE);
|
|
}
|
|
return Status;
|
|
}
|