diff options
Diffstat (limited to 'EmbeddedPkg/TemplateTimerDxe/Timer.c')
| -rw-r--r-- | EmbeddedPkg/TemplateTimerDxe/Timer.c | 373 |
1 files changed, 373 insertions, 0 deletions
diff --git a/EmbeddedPkg/TemplateTimerDxe/Timer.c b/EmbeddedPkg/TemplateTimerDxe/Timer.c new file mode 100644 index 0000000000..4bfa3e8622 --- /dev/null +++ b/EmbeddedPkg/TemplateTimerDxe/Timer.c @@ -0,0 +1,373 @@ +/** @file
+ Template for Timer Architecture Protocol driver of the ARM flavor
+
+ Copyright (c) 2008-2009, Apple Inc. All rights reserved.
+
+ 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/DebugLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiLib.h>
+#include <Library/PcdLib.h>
+#include <Library/IoLib.h>
+
+#include <Protocol/Timer.h>
+#include <Protocol/HardwareInterrupt.h>
+
+//
+// Get Base Address of timer block from platform .DSC file
+//
+#define TIMER_BASE ((UINTN)FixedPcdGet32 (PcdTimerBaseAddress) + 0x00c0)
+
+
+#define TIMER_CMD ((UINTN)FixedPcdGet32 (PcdTimerBaseAddress) + 0x00000004)
+#define TIMER_DATA ((UINTN)FixedPcdGet32 (PcdTimerBaseAddress) + 0x00000008)
+
+//
+// The notification function to call on every timer interrupt.
+// A bug in the compiler prevents us from initializing this here.
+//
+volatile EFI_TIMER_NOTIFY mTimerNotifyFunction;
+
+//
+// The current period of the timer interrupt
+//
+volatile UINT64 mTimerPeriod = 0;
+
+//
+// Cached copy of the Hardware Interrupt protocol instance
+//
+EFI_HARDWARE_INTERRUPT_PROTOCOL *gInterrupt = NULL;
+
+
+/**
+ C Interrupt Handler calledin the interrupt context when Source interrupt is active.
+
+ @param Source Source of the interrupt. Hardware routing off a specific platform defines
+ what source means.
+ @param SystemContext Pointer to system register context. Mostly used by debuggers and will
+ update the system context after the return from the interrupt if
+ modified. Don't change these values unless you know what you are doing
+
+**/
+VOID
+EFIAPI
+TimerInterruptHandler (
+ IN HARDWARE_INTERRUPT_SOURCE Source,
+ IN EFI_SYSTEM_CONTEXT SystemContext
+ )
+{
+ EFI_TPL OriginalTPL;
+
+ // Mask all interrupts
+ OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);
+
+ MmioWrite32 (TIMER_CMD, 0);
+
+ if (mTimerNotifyFunction) {
+ mTimerNotifyFunction (mTimerPeriod);
+ }
+
+ // restore state
+ gBS->RestoreTPL (OriginalTPL);
+}
+
+
+
+/**
+ 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 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 timer handler was registered.
+ @retval EFI_UNSUPPORTED The platform does not support timer interrupts.
+ @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.
+ @retval EFI_DEVICE_ERROR The timer handler could not be registered.
+
+**/
+EFI_STATUS
+EFIAPI
+TimerDriverRegisterHandler (
+ IN EFI_TIMER_ARCH_PROTOCOL *This,
+ IN EFI_TIMER_NOTIFY NotifyFunction
+ )
+{
+ //
+ // Check for invalid parameters
+ //
+ if (NotifyFunction == NULL && mTimerNotifyFunction == NULL) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ if (NotifyFunction != NULL && mTimerNotifyFunction != NULL) {
+ return EFI_ALREADY_STARTED;
+ }
+
+ 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 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
+TimerDriverSetTimerPeriod (
+ IN EFI_TIMER_ARCH_PROTOCOL *This,
+ IN UINT64 TimerPeriod
+ )
+{
+ EFI_STATUS Status;
+ UINT64 TimerCount;
+
+ if (TimerPeriod == 0) {
+ //
+ // Disable interrupt 0 and timer
+ //
+ MmioAnd32 (TIMER_DATA, 0);
+
+ Status = gInterrupt->DisableInterruptSource (gInterrupt, FixedPcdGet32 (PcdTimerVector));
+ } else {
+ //
+ // Convert TimerPeriod into Timer F counts
+ //
+ TimerCount = DivU64x32 (TimerPeriod + 5, 10);
+
+ //
+ // Program Timer F with the new count value
+ //
+ MmioWrite32 (TIMER_DATA, (UINT32)TimerCount);
+
+ //
+ // Enable interrupt and initialize and enable timer.
+ //
+ MmioOr32 (TIMER_CMD, 0x11);
+
+ Status = gInterrupt->EnableInterruptSource (gInterrupt, FixedPcdGet32 (PcdTimerVector));
+ }
+
+ //
+ // Save the new timer period
+ //
+ mTimerPeriod = TimerPeriod;
+ 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
+TimerDriverGetTimerPeriod (
+ IN EFI_TIMER_ARCH_PROTOCOL *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 EFI_TIMER_ARCH_PROTOCOL.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 This The EFI_TIMER_ARCH_PROTOCOL instance.
+
+ @retval EFI_SUCCESS The soft timer interrupt was generated.
+ @retval EFI_UNSUPPORTED The platform does not support the generation of soft timer interrupts.
+
+**/
+EFI_STATUS
+EFIAPI
+TimerDriverGenerateSoftInterrupt (
+ IN EFI_TIMER_ARCH_PROTOCOL *This
+ )
+{
+ return EFI_UNSUPPORTED;
+}
+
+
+/**
+ Interface stucture for the Timer Architectural Protocol.
+
+ @par Protocol Description:
+ This protocol provides the services to initialize a periodic timer
+ interrupt, and to register a handler that is called each time the timer
+ interrupt fires. It may also provide a service to adjust the rate of the
+ periodic timer interrupt. When a timer interrupt occurs, the handler is
+ passed the amount of time that has passed since the previous timer
+ interrupt.
+
+ @param RegisterHandler
+ Registers a handler that will be called each time the
+ timer interrupt fires. TimerPeriod defines the minimum
+ time between timer interrupts, so TimerPeriod will also
+ be the minimum time between calls to the registered
+ handler.
+
+ @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.
+
+ @param GenerateSoftInterrupt
+ Generates a soft timer interrupt that simulates the firing of
+ the timer interrupt. This service can be used to invoke the
+ registered handler if the timer interrupt has been masked for
+ a period of time.
+
+**/
+EFI_TIMER_ARCH_PROTOCOL gTimer = {
+ TimerDriverRegisterHandler,
+ TimerDriverSetTimerPeriod,
+ TimerDriverGetTimerPeriod,
+ TimerDriverGenerateSoftInterrupt
+};
+
+EFI_HANDLE gTimerHandle = NULL;
+
+
+/**
+ Initialize the state information for the 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
+TimerInitialize (
+ IN EFI_HANDLE ImageHandle,
+ IN EFI_SYSTEM_TABLE *SystemTable
+ )
+{
+ EFI_STATUS Status;
+
+ //
+ // Find the interrupt controller protocol. ASSERT if not found.
+ //
+ Status = gBS->LocateProtocol (&gHardwareInterruptProtocolGuid, NULL, ( VOID ** )&gInterrupt);
+ ASSERT_EFI_ERROR (Status);
+
+ MmioWrite32 (TIMER_CMD, 0x01);
+
+ //
+ // Force the timer to be disabled
+ //
+ Status = TimerDriverSetTimerPeriod (&gTimer, 0);
+ ASSERT_EFI_ERROR (Status);
+
+ //
+ // Install interrupt handler
+ //
+ Status = gInterrupt->RegisterInterruptSource (gInterrupt, FixedPcdGet32 (PcdTimerVector), TimerInterruptHandler);
+ ASSERT_EFI_ERROR (Status);
+
+ //
+ // Force the timer to be enabled at its default period
+ //
+ Status = TimerDriverSetTimerPeriod (&gTimer, FixedPcdGet32 (PcdTimerPeriod));
+ ASSERT_EFI_ERROR (Status);
+
+
+ //
+ // Install the Timer Architectural Protocol onto a new handle
+ //
+ Status = gBS->InstallMultipleProtocolInterfaces (
+ &gTimerHandle,
+ &gEfiTimerArchProtocolGuid, &gTimer,
+ NULL
+ );
+ ASSERT_EFI_ERROR (Status);
+
+ return Status;
+}
+
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