--- /dev/null
+/*++\r
+\r
+Copyright (c) 2006, Intel Corporation \r
+All rights reserved. This program and the accompanying materials \r
+are licensed and made available under the terms and conditions of the BSD License \r
+which accompanies this distribution. The full text of the license may be found at \r
+http://opensource.org/licenses/bsd-license.php \r
+ \r
+THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS, \r
+WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED. \r
+\r
+Module Name:\r
+\r
+ Timer.c\r
+\r
+Abstract:\r
+\r
+ NT Emulation Timer Architectural Protocol Driver as defined in DXE CIS\r
+\r
+ This Timer module uses an NT Thread to simulate the timer-tick driven\r
+ timer service. In the future, the Thread creation should possibly be \r
+ abstracted by the CPU architectural protocol\r
+\r
+--*/\r
+\r
+//\r
+// Include common header file for this module.\r
+//\r
+#include "CommonHeader.h"\r
+\r
+#include "Timer.h"\r
+\r
+//\r
+// Pointer to the CPU Architectural Protocol instance\r
+//\r
+EFI_CPU_ARCH_PROTOCOL *mCpu;\r
+\r
+//\r
+// The Timer Architectural Protocol that this driver produces\r
+//\r
+EFI_TIMER_ARCH_PROTOCOL mTimer = {\r
+ WinNtTimerDriverRegisterHandler,\r
+ WinNtTimerDriverSetTimerPeriod,\r
+ WinNtTimerDriverGetTimerPeriod,\r
+ WinNtTimerDriverGenerateSoftInterrupt\r
+};\r
+\r
+//\r
+// Define a global that we can use to shut down the NT timer thread when\r
+// the timer is canceled.\r
+//\r
+BOOLEAN mCancelTimerThread = FALSE;\r
+\r
+//\r
+// The notification function to call on every timer interrupt\r
+//\r
+EFI_TIMER_NOTIFY mTimerNotifyFunction = NULL;\r
+\r
+//\r
+// The current period of the timer interrupt\r
+//\r
+UINT64 mTimerPeriod;\r
+\r
+//\r
+// The thread handle for this driver\r
+//\r
+HANDLE mNtMainThreadHandle;\r
+\r
+//\r
+// The timer value from the last timer interrupt\r
+//\r
+UINT32 mNtLastTick;\r
+\r
+//\r
+// Critical section used to update varibles shared between the main thread and\r
+// the timer interrupt thread.\r
+//\r
+CRITICAL_SECTION mNtCriticalSection;\r
+\r
+//\r
+// Worker Functions\r
+//\r
+UINT mMMTimerThreadID = 0;\r
+\r
+VOID\r
+CALLBACK\r
+MMTimerThread (\r
+ UINT wTimerID,\r
+ UINT msg,\r
+ DWORD dwUser,\r
+ DWORD dw1,\r
+ DWORD dw2\r
+ )\r
+/*++\r
+\r
+Routine Description:\r
+\r
+ TODO: Add function description\r
+\r
+Arguments:\r
+\r
+ wTimerID - TODO: add argument description\r
+ msg - TODO: add argument description\r
+ dwUser - TODO: add argument description\r
+ dw1 - TODO: add argument description\r
+ dw2 - TODO: add argument description\r
+\r
+Returns:\r
+\r
+ TODO: add return values\r
+\r
+--*/\r
+{\r
+ EFI_TPL OriginalTPL;\r
+ UINT32 CurrentTick;\r
+ UINT32 Delta;\r
+ EFI_TIMER_NOTIFY CallbackFunction;\r
+ BOOLEAN InterruptState;\r
+\r
+ if (!mCancelTimerThread) {\r
+ \r
+ //\r
+ // Suspend the main thread until we are done\r
+ //\r
+\r
+ gWinNt->SuspendThread (mNtMainThreadHandle);\r
+\r
+ //\r
+ // If the timer thread is being canceled, then bail immediately.\r
+ // We check again here because there's a small window of time from when\r
+ // this thread was kicked off and when we suspended the main thread above.\r
+ //\r
+ if (mCancelTimerThread) {\r
+ gWinNt->ResumeThread (mNtMainThreadHandle);\r
+ gWinNt->timeKillEvent (wTimerID);\r
+ mMMTimerThreadID = 0;\r
+ return ;\r
+ }\r
+\r
+ mCpu->GetInterruptState (mCpu, &InterruptState);\r
+ while (!InterruptState) {\r
+ //\r
+ // Resume the main thread\r
+ //\r
+ gWinNt->ResumeThread (mNtMainThreadHandle);\r
+\r
+ //\r
+ // Wait for interrupts to be enabled.\r
+ //\r
+ mCpu->GetInterruptState (mCpu, &InterruptState);\r
+ while (!InterruptState) {\r
+ gWinNt->Sleep (0);\r
+ mCpu->GetInterruptState (mCpu, &InterruptState);\r
+ }\r
+ \r
+ //\r
+ // Suspend the main thread until we are done\r
+ //\r
+ gWinNt->SuspendThread (mNtMainThreadHandle);\r
+ mCpu->GetInterruptState (mCpu, &InterruptState);\r
+ }\r
+\r
+ //\r
+ // Get the current system tick\r
+ //\r
+ CurrentTick = gWinNt->GetTickCount ();\r
+ Delta = CurrentTick - mNtLastTick;\r
+ mNtLastTick = CurrentTick;\r
+\r
+ //\r
+ // If delay was more then 1 second, ignore it (probably debugging case)\r
+ //\r
+ if (Delta < 1000) {\r
+\r
+ OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);\r
+\r
+ //\r
+ // Inform the firmware of an "timer interrupt". The time\r
+ // expired since the last call is 10,000 times the number\r
+ // of ms. (or 100ns units)\r
+ //\r
+ gWinNt->EnterCriticalSection (&mNtCriticalSection);\r
+ CallbackFunction = mTimerNotifyFunction;\r
+ gWinNt->LeaveCriticalSection (&mNtCriticalSection);\r
+\r
+ //\r
+ // Only invoke the callback function if a Non-NULL handler has been\r
+ // registered. Assume all other handlers are legal.\r
+ //\r
+ if (CallbackFunction != NULL) {\r
+ CallbackFunction ((UINT64) (Delta * 10000));\r
+ }\r
+\r
+ gBS->RestoreTPL (OriginalTPL);\r
+\r
+ }\r
+\r
+ //\r
+ // Resume the main thread\r
+ //\r
+ gWinNt->ResumeThread (mNtMainThreadHandle);\r
+ } else {\r
+ gWinNt->timeKillEvent (wTimerID);\r
+ mMMTimerThreadID = 0;\r
+ }\r
+\r
+}\r
+\r
+UINT\r
+CreateNtTimer (\r
+ VOID\r
+ )\r
+/*++\r
+\r
+Routine Description:\r
+\r
+ It is used to emulate a platform \r
+ timer-driver interrupt handler. \r
+\r
+Returns:\r
+\r
+ Timer ID\r
+\r
+--*/\r
+// TODO: function comment is missing 'Arguments:'\r
+{\r
+ UINT32 SleepCount;\r
+\r
+ //\r
+ // Set our thread priority higher than the "main" thread.\r
+ //\r
+ gWinNt->SetThreadPriority (\r
+ gWinNt->GetCurrentThread (),\r
+ THREAD_PRIORITY_HIGHEST\r
+ );\r
+\r
+ //\r
+ // Calc the appropriate interval\r
+ //\r
+ gWinNt->EnterCriticalSection (&mNtCriticalSection);\r
+ SleepCount = (UINT32) (mTimerPeriod + 5000) / 10000;\r
+ gWinNt->LeaveCriticalSection (&mNtCriticalSection);\r
+\r
+ return gWinNt->timeSetEvent (\r
+ SleepCount,\r
+ 0,\r
+ MMTimerThread,\r
+ (DWORD_PTR) NULL,\r
+ TIME_PERIODIC | TIME_KILL_SYNCHRONOUS | TIME_CALLBACK_FUNCTION\r
+ );\r
+\r
+}\r
+\r
+EFI_STATUS\r
+EFIAPI\r
+WinNtTimerDriverRegisterHandler (\r
+ IN EFI_TIMER_ARCH_PROTOCOL *This,\r
+ IN EFI_TIMER_NOTIFY NotifyFunction\r
+ )\r
+/*++\r
+\r
+Routine Description:\r
+\r
+ This function registers the handler NotifyFunction so it is called every time \r
+ the timer interrupt fires. It also passes the amount of time since the last \r
+ handler call to the NotifyFunction. If NotifyFunction is NULL, then the \r
+ handler is unregistered. If the handler is registered, then EFI_SUCCESS is \r
+ returned. If the CPU does not support registering a timer interrupt handler, \r
+ then EFI_UNSUPPORTED is returned. If an attempt is made to register a handler \r
+ when a handler is already registered, then EFI_ALREADY_STARTED is returned. \r
+ If an attempt is made to unregister a handler when a handler is not registered, \r
+ then EFI_INVALID_PARAMETER is returned. If an error occurs attempting to \r
+ register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR \r
+ is returned.\r
+\r
+Arguments:\r
+\r
+ This - The EFI_TIMER_ARCH_PROTOCOL instance.\r
+\r
+ NotifyFunction - The function to call when a timer interrupt fires. This \r
+ function executes at TPL_HIGH_LEVEL. The DXE Core will \r
+ register a handler for the timer interrupt, so it can know \r
+ how much time has passed. This information is used to \r
+ signal timer based events. NULL will unregister the handler.\r
+\r
+Returns: \r
+\r
+ EFI_SUCCESS - The timer handler was registered.\r
+\r
+ EFI_UNSUPPORTED - The platform does not support timer interrupts.\r
+\r
+ EFI_ALREADY_STARTED - NotifyFunction is not NULL, and a handler is already \r
+ registered.\r
+\r
+ EFI_INVALID_PARAMETER - NotifyFunction is NULL, and a handler was not \r
+ previously registered.\r
+\r
+ EFI_DEVICE_ERROR - The timer handler could not be registered.\r
+\r
+--*/\r
+{\r
+ //\r
+ // Check for invalid parameters\r
+ //\r
+ if (NotifyFunction == NULL && mTimerNotifyFunction == NULL) {\r
+ return EFI_INVALID_PARAMETER;\r
+ }\r
+\r
+ if (NotifyFunction != NULL && mTimerNotifyFunction != NULL) {\r
+ return EFI_ALREADY_STARTED;\r
+ }\r
+\r
+ //\r
+ // Use Critical Section to update the notification function that is\r
+ // used from the timer interrupt thread.\r
+ //\r
+ gWinNt->EnterCriticalSection (&mNtCriticalSection);\r
+\r
+ mTimerNotifyFunction = NotifyFunction;\r
+\r
+ gWinNt->LeaveCriticalSection (&mNtCriticalSection);\r
+\r
+ return EFI_SUCCESS;\r
+}\r
+\r
+EFI_STATUS\r
+EFIAPI\r
+WinNtTimerDriverSetTimerPeriod (\r
+ IN EFI_TIMER_ARCH_PROTOCOL *This,\r
+ IN UINT64 TimerPeriod\r
+ )\r
+/*++\r
+\r
+Routine Description:\r
+\r
+ This function adjusts the period of timer interrupts to the value specified \r
+ by TimerPeriod. If the timer period is updated, then the selected timer \r
+ period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned. If \r
+ the timer hardware is not programmable, then EFI_UNSUPPORTED is returned. \r
+ If an error occurs while attempting to update the timer period, then the \r
+ timer hardware will be put back in its state prior to this call, and \r
+ EFI_DEVICE_ERROR is returned. If TimerPeriod is 0, then the timer interrupt \r
+ is disabled. This is not the same as disabling the CPU's interrupts. \r
+ Instead, it must either turn off the timer hardware, or it must adjust the \r
+ interrupt controller so that a CPU interrupt is not generated when the timer \r
+ interrupt fires. \r
+\r
+Arguments:\r
+\r
+ This - The EFI_TIMER_ARCH_PROTOCOL instance.\r
+\r
+ TimerPeriod - The rate to program the timer interrupt in 100 nS units. If \r
+ the timer hardware is not programmable, then EFI_UNSUPPORTED is \r
+ returned. If the timer is programmable, then the timer period \r
+ will be rounded up to the nearest timer period that is supported \r
+ by the timer hardware. If TimerPeriod is set to 0, then the \r
+ timer interrupts will be disabled.\r
+\r
+Returns: \r
+\r
+ EFI_SUCCESS - The timer period was changed.\r
+\r
+ EFI_UNSUPPORTED - The platform cannot change the period of the timer interrupt.\r
+\r
+ EFI_DEVICE_ERROR - The timer period could not be changed due to a device error.\r
+\r
+--*/\r
+{\r
+\r
+ //\r
+ // If TimerPeriod is 0, then the timer thread should be canceled\r
+ //\r
+ if (TimerPeriod == 0) {\r
+ //\r
+ // Cancel the timer thread\r
+ //\r
+ gWinNt->EnterCriticalSection (&mNtCriticalSection);\r
+\r
+ mCancelTimerThread = TRUE;\r
+\r
+ gWinNt->LeaveCriticalSection (&mNtCriticalSection);\r
+\r
+ //\r
+ // Wait for the timer thread to exit\r
+ //\r
+\r
+ if (mMMTimerThreadID) {\r
+ gWinNt->timeKillEvent (mMMTimerThreadID);\r
+ }\r
+\r
+ mMMTimerThreadID = 0;\r
+\r
+ //\r
+ // Update the timer period\r
+ //\r
+ gWinNt->EnterCriticalSection (&mNtCriticalSection);\r
+\r
+ mTimerPeriod = TimerPeriod;\r
+\r
+ gWinNt->LeaveCriticalSection (&mNtCriticalSection);\r
+\r
+ //\r
+ // NULL out the thread handle so it will be re-created if the timer is enabled again\r
+ //\r
+\r
+ } else if ((TimerPeriod > TIMER_MINIMUM_VALUE) && (TimerPeriod < TIMER_MAXIMUM_VALUE)) {\r
+ //\r
+ // If the TimerPeriod is valid, then create and/or adjust the period of the timer thread\r
+ //\r
+ gWinNt->EnterCriticalSection (&mNtCriticalSection);\r
+\r
+ mTimerPeriod = TimerPeriod;\r
+\r
+ mCancelTimerThread = FALSE;\r
+\r
+ gWinNt->LeaveCriticalSection (&mNtCriticalSection);\r
+\r
+ //\r
+ // Get the starting tick location if we are just starting the timer thread\r
+ //\r
+ mNtLastTick = gWinNt->GetTickCount ();\r
+\r
+ if (mMMTimerThreadID) {\r
+ gWinNt->timeKillEvent (mMMTimerThreadID);\r
+ }\r
+\r
+ mMMTimerThreadID = 0;\r
+\r
+ mMMTimerThreadID = CreateNtTimer ();\r
+\r
+ }\r
+\r
+ return EFI_SUCCESS;\r
+}\r
+\r
+EFI_STATUS\r
+EFIAPI\r
+WinNtTimerDriverGetTimerPeriod (\r
+ IN EFI_TIMER_ARCH_PROTOCOL *This,\r
+ OUT UINT64 *TimerPeriod\r
+ )\r
+/*++\r
+\r
+Routine Description:\r
+\r
+ This function retrieves the period of timer interrupts in 100 ns units, \r
+ returns that value in TimerPeriod, and returns EFI_SUCCESS. If TimerPeriod \r
+ is NULL, then EFI_INVALID_PARAMETER is returned. If a TimerPeriod of 0 is \r
+ returned, then the timer is currently disabled.\r
+\r
+Arguments:\r
+\r
+ This - The EFI_TIMER_ARCH_PROTOCOL instance.\r
+\r
+ TimerPeriod - A pointer to the timer period to retrieve in 100 ns units. If \r
+ 0 is returned, then the timer is currently disabled.\r
+\r
+Returns: \r
+\r
+ EFI_SUCCESS - The timer period was returned in TimerPeriod.\r
+\r
+ EFI_INVALID_PARAMETER - TimerPeriod is NULL.\r
+\r
+--*/\r
+{\r
+ if (TimerPeriod == NULL) {\r
+ return EFI_INVALID_PARAMETER;\r
+ }\r
+\r
+ *TimerPeriod = mTimerPeriod;\r
+\r
+ return EFI_SUCCESS;\r
+}\r
+\r
+EFI_STATUS\r
+EFIAPI\r
+WinNtTimerDriverGenerateSoftInterrupt (\r
+ IN EFI_TIMER_ARCH_PROTOCOL *This\r
+ )\r
+/*++\r
+\r
+Routine Description:\r
+\r
+ This function generates a soft timer interrupt. If the platform does not support soft \r
+ timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned. \r
+ If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler() \r
+ service, then a soft timer interrupt will be generated. If the timer interrupt is \r
+ enabled when this service is called, then the registered handler will be invoked. The \r
+ registered handler should not be able to distinguish a hardware-generated timer \r
+ interrupt from a software-generated timer interrupt.\r
+\r
+Arguments:\r
+\r
+ This - The EFI_TIMER_ARCH_PROTOCOL instance.\r
+\r
+Returns: \r
+\r
+ EFI_SUCCESS - The soft timer interrupt was generated.\r
+\r
+ EFI_UNSUPPORTEDT - The platform does not support the generation of soft timer interrupts.\r
+\r
+--*/\r
+{\r
+ return EFI_UNSUPPORTED;\r
+}\r
+\r
+\r
+EFI_STATUS\r
+EFIAPI\r
+WinNtTimerDriverInitialize (\r
+ IN EFI_HANDLE ImageHandle,\r
+ IN EFI_SYSTEM_TABLE *SystemTable\r
+ )\r
+/*++\r
+\r
+Routine Description:\r
+\r
+ Initialize the Timer Architectural Protocol driver\r
+\r
+Arguments:\r
+\r
+ ImageHandle - ImageHandle of the loaded driver\r
+\r
+ SystemTable - Pointer to the System Table\r
+\r
+Returns:\r
+\r
+ EFI_SUCCESS - Timer Architectural Protocol created\r
+\r
+ EFI_OUT_OF_RESOURCES - Not enough resources available to initialize driver.\r
+ \r
+ EFI_DEVICE_ERROR - A device error occured attempting to initialize the driver.\r
+\r
+--*/\r
+{\r
+ EFI_STATUS Status;\r
+ UINTN Result;\r
+ EFI_HANDLE Handle;\r
+\r
+ //\r
+ // Make sure the Timer Architectural Protocol is not already installed in the system\r
+ //\r
+ ASSERT_PROTOCOL_ALREADY_INSTALLED (NULL, &gEfiTimerArchProtocolGuid);\r
+\r
+ //\r
+ // Get the CPU Architectural Protocol instance\r
+ //\r
+ Status = gBS->LocateProtocol (&gEfiCpuArchProtocolGuid, NULL, &mCpu);\r
+ ASSERT_EFI_ERROR (Status);\r
+\r
+ //\r
+ // Get our handle so the timer tick thread can suspend\r
+ //\r
+ Result = gWinNt->DuplicateHandle (\r
+ gWinNt->GetCurrentProcess (),\r
+ gWinNt->GetCurrentThread (),\r
+ gWinNt->GetCurrentProcess (),\r
+ &mNtMainThreadHandle,\r
+ 0,\r
+ FALSE,\r
+ DUPLICATE_SAME_ACCESS\r
+ );\r
+ if (Result == 0) {\r
+ return EFI_DEVICE_ERROR;\r
+ }\r
+\r
+ //\r
+ // Initialize Critical Section used to update variables shared between the main\r
+ // thread and the timer interrupt thread.\r
+ //\r
+ gWinNt->InitializeCriticalSection (&mNtCriticalSection);\r
+\r
+ //\r
+ // Start the timer thread at the default timer period\r
+ //\r
+ Status = mTimer.SetTimerPeriod (&mTimer, DEFAULT_TIMER_TICK_DURATION);\r
+ if (EFI_ERROR (Status)) {\r
+ gWinNt->DeleteCriticalSection (&mNtCriticalSection);\r
+ return Status;\r
+ }\r
+\r
+ //\r
+ // Install the Timer Architectural Protocol onto a new handle\r
+ //\r
+ Handle = NULL;\r
+ Status = gBS->InstallProtocolInterface (\r
+ &Handle,\r
+ &gEfiTimerArchProtocolGuid,\r
+ EFI_NATIVE_INTERFACE,\r
+ &mTimer\r
+ );\r
+ if (EFI_ERROR (Status)) {\r
+ //\r
+ // Cancel the timer\r
+ //\r
+ mTimer.SetTimerPeriod (&mTimer, 0);\r
+ gWinNt->DeleteCriticalSection (&mNtCriticalSection);\r
+ return Status;\r
+ }\r
+\r
+ return EFI_SUCCESS;\r
+}\r