/** @file Timer Architectural PPI and Time0 notify callback ;****************************************************************************** ;* Copyright (c) 2015 - 2020, Insyde Software Corporation. All Rights Reserved. ;* ;* You may not reproduce, distribute, publish, display, perform, modify, adapt, ;* transmit, broadcast, present, recite, release, license or otherwise exploit ;* any part of this publication in any form, by any means, without the prior ;* written permission of Insyde Software Corporation. ;* ;****************************************************************************** */ #include H2O_LEGACY_8259_PPI *m8259Ppi; H2O_CPU_ARCH_PPI *mCpuPpi; CONST EFI_PEI_SERVICES **mPeiServices; // // The current period of the timer interrupt // volatile UINT64 mTimerPeriod = 0; // // The time of twice timer interrupt duration // volatile UINTN mPreAcpiTick = 0; // // The notification function to call on every timer interrupt. // volatile H2O_TIMER_NOTIFY mTimerNotifyFunction; // // PMIO BAR Registers // UINT16 mPchPmioBase; // // The Timer Architectural PPI that this module produces // H2O_TIMER_ARCH_PPI mTimer = { TimerDriverRegisterHandler, TimerDriverSetTimerPeriod, TimerDriverGetTimerPeriod, TimerDriverGenerateSoftInterrupt }; STATIC EFI_PEI_PPI_DESCRIPTOR mTimerPpiList = { (EFI_PEI_PPI_DESCRIPTOR_PPI | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST), &gH2OTimerArchPpiGuid, &mTimer }; STATIC EFI_PEI_PPI_DESCRIPTOR mEventPpiList = { (EFI_PEI_PPI_DESCRIPTOR_PPI | EFI_PEI_PPI_DESCRIPTOR_TERMINATE_LIST), &gH2OTimerEventPpiGuid, NULL }; /** Sets the counter value for Timer #0 in a legacy 8254 timer. @param[in] Count The 16-bit counter value to program into Timer #0 of the legacy 8254 timer. @retval None **/ VOID SetPitCount ( IN UINT16 Count ) { UINT8 Data; // // 0x36 = Read/Write counter LSB then MSB, Mode3 square wave output from this timer. // Check register Counter Access Ports Register(0x40/41/42 for counter0/1/2) in PCH B0D31F0 // check Counter Operating Mode 0~5 at 8254 Timer function description in LPC in EDS. // Data = 0x36; IoWrite8 (TIMER_CONTROL_PORT, Data); IoWrite8 (TIMER0_COUNT_PORT, (UINT8) Count); IoWrite8 (TIMER0_COUNT_PORT, (UINT8) (Count >> 8)); } /** Get the current ACPI counter's value @param[in] None @retval UINT32 The value of the counter **/ UINT32 GetAcpiTick ( VOID ) { UINT32 Tick = 0; Tick = IoRead32 ((UINTN) (mPchPmioBase + R_ACPI_IO_PM1_TMR)); return Tick; } /** Measure the 8254 timer interrupt use the ACPI time counter @param[in] TimePeriod The current period of the timer interrupt @retval UINT64 The real system time pass between the sequence 8254 timer interrupt **/ UINT64 MeasureTimeLost ( IN UINT64 TimePeriod ) { UINT32 CurrentTick; UINT32 EndTick; UINT64 LostTime; CurrentTick = GetAcpiTick (); EndTick = CurrentTick; if (CurrentTick < mPreAcpiTick) { EndTick = CurrentTick + 0x1000000; } // // The calculation of the lost system time should be very accurate, we use // the shift calcu to make sure the value's accurate: // the origenal formula is: // (EndTick - mPreAcpiTick) * 10,000,000 // LostTime = ----------------------------------------------- // (3,579,545 Hz / 1,193,182 Hz) * 1,193,182 Hz // // Note: the 3,579,545 Hz is the ACPI timer's clock; // the 1,193,182 Hz is the 8254 timer's clock; // LostTime = RShiftU64 ( MultU64x32 ((UINT64) (EndTick - mPreAcpiTick), 46869689) + 0x00FFFFFF, 24 ); if (LostTime != 0) { mPreAcpiTick = CurrentTick; } return LostTime; } /** 8254 Timer #0 Interrupt Handler @param[in] InterruptType The type of interrupt that occured @param[in] SystemContext A pointer to the system context when the interrupt occured @retval None **/ VOID TimerInterruptHandler ( IN CONST EFI_EXCEPTION_TYPE InterruptType, IN CONST EFI_SYSTEM_CONTEXT SystemContext ) { m8259Ppi->EndOfInterrupt (m8259Ppi, Efi8259Irq0); if (mTimerNotifyFunction) { // // If we have the timer interrupt miss, then we use // the platform ACPI time counter to retrieve the time lost // mTimerNotifyFunction (MeasureTimeLost (mTimerPeriod)); } } /** Reinstall PPI to notify other callback function. @param[in] None @retval None **/ VOID ThunkNotifyFunction ( IN CONST EFI_PEI_SERVICES **PeiServices ) { // DEBUG((DEBUG_INFO, "<<--Start SmartTimerPei ThunkNotify-->>\n")); (**PeiServices).ReInstallPpi (PeiServices, &mEventPpiList, &mEventPpiList); // DEBUG((DEBUG_INFO, "<<--End SmartTimerPei ThunkNotify-->>\n")); } /** Timer interrupt notify function. This notification function to call on every timer interrupt. @param[in] Time The real system time pass between the sequence 8254 timer interrupt @retval None **/ VOID TimerNotifyFunction ( IN UINT64 Time ) { ThunkNotifyFunction (mPeiServices); } /** This function registers the handler NotifyFunction so it is called every time the timer interrupt fires. It also passes the amount of time since the last handler call to the NotifyFunction. If NotifyFunction is NULL, then the handler is unregistered. If the handler is registered, then EFI_SUCCESS is returned. If the CPU does not support registering a timer interrupt handler, then EFI_UNSUPPORTED 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 unregister a handler when a handler is not registered, then EFI_INVALID_PARAMETER is returned. If an error occurs attempting to register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR is returned. @param[in] This The H2O_TIMER_ARCH_PPI instance. @param[in] 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 timer handler was registered. @exception EFI_UNSUPPORTED The CPU does not support registering a timer interrupt handler @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 TimerDriverRegisterHandler ( IN H2O_TIMER_ARCH_PPI *This, IN H2O_TIMER_NOTIFY NotifyFunction ) { // // If an attempt is made to unregister a handler when a handler is not registered, // then EFI_INVALID_PARAMETER is returned. // if (mTimerNotifyFunction == NULL && NotifyFunction == NULL) { return EFI_INVALID_PARAMETER; } // // If an attempt is made to register a handler // when a handler is already registered, then EFI_ALREADY_STARTED is returned. // if (mTimerNotifyFunction != NULL && NotifyFunction != NULL) { return EFI_ALREADY_STARTED; } // // If the CPU does not support registering a timer interrupt handler, then EFI_UNSUPPORTED is returned. // if (mCpuPpi == NULL || m8259Ppi == NULL) { return EFI_UNSUPPORTED; } if (NotifyFunction == NULL) { // // If NotifyFunction is NULL, then the handler is unregistered. // mTimerNotifyFunction = NULL; } else { mTimerNotifyFunction = NotifyFunction; } return EFI_SUCCESS; } /** 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[in] This The H2O_TIMER_ARCH_PPI instance. @param[in] 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. **/ EFI_STATUS EFIAPI TimerDriverSetTimerPeriod ( IN H2O_TIMER_ARCH_PPI *This, IN UINT64 TimerPeriod ) { UINT64 TimerCount; // // The basic clock is 1.19318 MHz or 0.119318 ticks per 100 ns. // TimerPeriod * 0.119318 = 8254 timer divisor. Using integer arithmetic // TimerCount = (TimerPeriod * 119318)/1000000. // // Round up to next highest integer. This guarantees that the timer is // equal to or slightly longer than the requested time. // TimerCount = ((TimerPeriod * 119318) + 500000)/1000000 // // Note that a TimerCount of 0 is equivalent to a count of 65,536 // // Since TimerCount is limited to 16 bits for IA32, TimerPeriod is limited // to 20 bits. // if (TimerPeriod == 0) { // // Disable timer interrupt for a TimerPeriod of 0 // m8259Ppi->DisableIrq (m8259Ppi, Efi8259Irq0); } else { // // Convert TimerPeriod into 8254 counts // TimerCount = DivU64x32Remainder (MultU64x32 (119318, (UINT32) TimerPeriod) + 500000, 1000000, 0); // // Check for overflow // if (TimerCount >= 65536) { TimerCount = 0; if (TimerPeriod >= DEFAULT_TIMER_TICK_DURATION) { TimerPeriod = DEFAULT_TIMER_TICK_DURATION; } } // // Program the 8254 timer with the new count value // SetPitCount ((UINT16) TimerCount); // // Enable timer interrupt // m8259Ppi->EnableIrq (m8259Ppi, Efi8259Irq0, FALSE); } // // Save the new timer period // mTimerPeriod = TimerPeriod; return EFI_SUCCESS; } /** 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[in] This The H2O_TIMER_ARCH_PPI instance. @param[out] 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 TimerDriverGetTimerPeriod ( IN H2O_TIMER_ARCH_PPI *This, OUT UINT64 *TimerPeriod ) { if (TimerPeriod == NULL) { return EFI_INVALID_PARAMETER; } *TimerPeriod = mTimerPeriod; return EFI_SUCCESS; } /** This function generates a soft timer interrupt. If the platform does not support soft timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned. If a handler has been registered through the H2O_TIMER_ARCH_PPI.RegisterHandler() service, then a soft timer interrupt will be generated. If the timer interrupt is enabled when this service is called, then the registered handler will be invoked. The registered handler should not be able to distinguish a hardware-generated timer interrupt from a software-generated timer interrupt. @param[in] This The H2O_TIMER_ARCH_PPI instance. @retval EFI_SUCCESS The soft timer interrupt was generated. **/ EFI_STATUS EFIAPI TimerDriverGenerateSoftInterrupt ( IN H2O_TIMER_ARCH_PPI *This ) { return EFI_UNSUPPORTED; } EFI_STATUS EFIAPI TimerPeiEntry ( IN EFI_PEI_FILE_HANDLE FileHandle, IN CONST EFI_PEI_SERVICES **PeiServices ) { EFI_STATUS Status; UINT32 TimerVector; UINTN Size; H2O_PEI_TIMER_DATA_HOB *DataHob; m8259Ppi = NULL; mCpuPpi = NULL; mPeiServices = PeiServices; // // Make sure the Timer Architectural Protocol is not already installed in the system // Status = (**PeiServices).LocatePpi (PeiServices, &gH2OTimerArchPpiGuid, 0, NULL, NULL); if (!EFI_ERROR(Status)) { return EFI_ALREADY_STARTED; } // // Find the CPU architectural protocol. ASSERT if not found. // Status = (**PeiServices).LocatePpi (PeiServices, &gH2OCpuArchPpiGuid, 0, NULL, (VOID**)&mCpuPpi); ASSERT_EFI_ERROR (Status); // // Find the Legacy8259 protocol. ASSERT if not found. // Status = (**PeiServices).LocatePpi (PeiServices, &gH2OLegacy8259PpiGuid, 0, NULL, (VOID**)&m8259Ppi); ASSERT_EFI_ERROR (Status); mPchPmioBase = PcdGet16 (PcdPerfPkgAcpiIoPortBaseAddress); ASSERT (mPchPmioBase != 0); DEBUG ((DEBUG_INFO, "PeiTimer: mPchPmioBase=0x%x\n",mPchPmioBase)); // // Force the timer to be disabled // Status = TimerDriverSetTimerPeriod (&mTimer, 0); ASSERT_EFI_ERROR (Status); // // Get the interrupt vector number corresponding to IRQ0 from the 8259 driver // TimerVector = 0; Status = m8259Ppi->GetVector (m8259Ppi, Efi8259Irq0, (UINT8 *) &TimerVector); ASSERT_EFI_ERROR (Status); // // Install interrupt handler for 8254 Timer #0 (ISA IRQ0) // Status = mCpuPpi->RegisterInterruptHandler (mCpuPpi, TimerVector, TimerInterruptHandler); ASSERT_EFI_ERROR (Status); // // Register Timer notify callback function // TimerDriverRegisterHandler (&mTimer, TimerNotifyFunction); // // Pre-install Timer Notify event PPI // Status = (**PeiServices).InstallPpi (PeiServices, &mEventPpiList); ASSERT_EFI_ERROR (Status); // // Force the timer to be enabled at its default period // Status = TimerDriverSetTimerPeriod (&mTimer, DEFAULT_TIMER_TICK_DURATION); ASSERT_EFI_ERROR (Status); // // Begin the ACPI timer counter // mPreAcpiTick = GetAcpiTick (); // // Install the Timer Architectural Ppi // Status = (**PeiServices).InstallPpi (PeiServices, &mTimerPpiList); ASSERT_EFI_ERROR (Status); // // Save the PeiService point and CallbackFunction point // Size = sizeof (H2O_PEI_TIMER_DATA_HOB); DataHob = BuildGuidHob (&gH2OPeiTimerDataHobGuid, Size); DataHob->PeiServicesPoint = (UINT32)PeiServices; DataHob->CallBackFunction = (UINT32)ThunkNotifyFunction; DataHob->MasterBaseVector = PcdGet8(PcdH2OInterruptMasterBaseVector); mCpuPpi->EnableInterrupt(mCpuPpi); DEBUG ((DEBUG_INFO, "PeiTimer: Create H2OPeiTimerDataHob\n")); DEBUG ((DEBUG_INFO, " FunctionPoint = 0x%X\n",DataHob->CallBackFunction)); DEBUG ((DEBUG_INFO, " PeiServicesPoint = 0x%X\n",DataHob->PeiServicesPoint)); return Status; }