--- /dev/null
+/*++ @file\r
+ Emu Emulation Timer Architectural Protocol Driver as defined in DXE CIS\r
+\r
+ This Timer module uses an Emu 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
+Copyright (c) 2004, Intel Corporation. All rights reserved.<BR>\r
+Portions copyright (c) 2010 - 2011, Apple Inc. All rights reserved.\r
+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
+\r
+**/\r
+\r
+#include "PiDxe.h"\r
+#include <Protocol/Timer.h>\r
+#include <Protocol/Cpu.h>\r
+#include "Timer.h"\r
+#include <Library/BaseLib.h>\r
+#include <Library/DebugLib.h>\r
+#include <Library/UefiLib.h>\r
+#include <Library/UefiDriverEntryPoint.h>\r
+#include <Library/MemoryAllocationLib.h>\r
+#include <Library/UefiBootServicesTableLib.h>\r
+#include <Library/EmuThunkLib.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
+ EmuTimerDriverRegisterHandler,\r
+ EmuTimerDriverSetTimerPeriod,\r
+ EmuTimerDriverGetTimerPeriod,\r
+ EmuTimerDriverGenerateSoftInterrupt\r
+};\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 mTimerPeriodMs;\r
+\r
+\r
+VOID\r
+EFIAPI\r
+TimerCallback (UINT64 DeltaMs)\r
+{\r
+ EFI_TPL OriginalTPL;\r
+ EFI_TIMER_NOTIFY CallbackFunction;\r
+\r
+\r
+ OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);\r
+\r
+ if (OriginalTPL < TPL_HIGH_LEVEL) {\r
+ CallbackFunction = mTimerNotifyFunction;\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) (DeltaMs * 10000));\r
+ }\r
+ }\r
+\r
+ gBS->RestoreTPL (OriginalTPL);\r
+\r
+}\r
+\r
+EFI_STATUS\r
+EFIAPI\r
+EmuTimerDriverRegisterHandler (\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
+ if (NotifyFunction == NULL) {\r
+ /* Disable timer. */\r
+ gEmuThunk->SetTimer (0, TimerCallback);\r
+ } else if (mTimerNotifyFunction == NULL) {\r
+ /* Enable Timer. */\r
+ gEmuThunk->SetTimer (mTimerPeriodMs, TimerCallback);\r
+ }\r
+ mTimerNotifyFunction = NotifyFunction;\r
+\r
+ return EFI_SUCCESS;\r
+}\r
+\r
+EFI_STATUS\r
+EFIAPI\r
+EmuTimerDriverSetTimerPeriod (\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
+ // If the TimerPeriod is valid, then create and/or adjust the period of the timer thread\r
+ //\r
+ if (TimerPeriod == 0\r
+ || ((TimerPeriod > TIMER_MINIMUM_VALUE)\r
+ && (TimerPeriod < TIMER_MAXIMUM_VALUE))) {\r
+ mTimerPeriodMs = DivU64x32 (TimerPeriod + 5000, 10000);\r
+\r
+ gEmuThunk->SetTimer (mTimerPeriodMs, TimerCallback);\r
+ }\r
+\r
+ return EFI_SUCCESS;\r
+}\r
+\r
+EFI_STATUS\r
+EFIAPI\r
+EmuTimerDriverGetTimerPeriod (\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 = mTimerPeriodMs * 10000;\r
+\r
+ return EFI_SUCCESS;\r
+}\r
+\r
+EFI_STATUS\r
+EFIAPI\r
+EmuTimerDriverGenerateSoftInterrupt (\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
+EFI_STATUS\r
+EFIAPI\r
+EmuTimerDriverInitialize (\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
+ 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, (void *)&mCpu);\r
+ ASSERT_EFI_ERROR (Status);\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
+ 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
+ return Status;\r
+ }\r
+\r
+\r
+ return EFI_SUCCESS;\r
+}\r