OvmfPkg/OvmfXen: Introduce XenTimerDxe

"OvmfPkg/8254TimerDxe" is replaced with a Xen-specific
EFI_TIMER_ARCH_PROTOCOL implementation. Also remove
8259InterruptControllerDxe as it is not used anymore.

This Timer uses the local APIC timer as time source as it can work on
both a Xen PVH guest and an HVM one.

Based on the "OvmfPkg/8254TimerDxe" implementation.

Ref: https://bugzilla.tianocore.org/show_bug.cgi?id=1689
Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20190813113119.14804-31-anthony.perard@citrix.com>

3 files changed, 574 insertions, 0 deletions

diff --git a/OvmfPkg/XenTimerDxe/XenTimerDxe.c b/OvmfPkg/XenTimerDxe/XenTimerDxe.c
new file mode 100644
index 0000000000..9f9e04766c
--- /dev/null
+++ b/OvmfPkg/XenTimerDxe/XenTimerDxe.c
@@ -0,0 +1,355 @@
+/** @file

+  Timer Architectural Protocol as defined in the DXE CIS

+

+Copyright (c) 2005 - 2018, Intel Corporation. All rights reserved.<BR>

+Copyright (c) 2019, Citrix Systems, Inc.

+

+SPDX-License-Identifier: BSD-2-Clause-Patent

+

+**/

+

+#include "XenTimerDxe.h"

+

+//

+// The handle onto which the Timer Architectural Protocol will be installed

+//

+EFI_HANDLE                mTimerHandle = NULL;

+

+//

+// The Timer Architectural Protocol that this driver produces

+//

+EFI_TIMER_ARCH_PROTOCOL   mTimer = {

+  TimerDriverRegisterHandler,

+  TimerDriverSetTimerPeriod,

+  TimerDriverGetTimerPeriod,

+  TimerDriverGenerateSoftInterrupt

+};

+

+//

+// Pointer to the CPU Architectural Protocol instance

+//

+EFI_CPU_ARCH_PROTOCOL     *mCpu;

+

+//

+// The notification function to call on every timer interrupt.

+// A bug in the compiler prevents us from initializing this here.

+//

+EFI_TIMER_NOTIFY mTimerNotifyFunction;

+

+//

+// The current period of the timer interrupt

+//

+volatile UINT64           mTimerPeriod = 0;

+

+//

+// Worker Functions

+//

+/**

+  Interrupt Handler.

+

+  @param InterruptType    The type of interrupt that occurred

+  @param SystemContext    A pointer to the system context when the interrupt occurred

+**/

+VOID

+EFIAPI

+TimerInterruptHandler (

+  IN EFI_EXCEPTION_TYPE   InterruptType,

+  IN EFI_SYSTEM_CONTEXT   SystemContext

+  )

+{

+  EFI_TPL OriginalTPL;

+

+  OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);

+

+  SendApicEoi();

+

+  if (mTimerNotifyFunction != NULL) {

+    //

+    // @bug : This does not handle missed timer interrupts

+    //

+    mTimerNotifyFunction (mTimerPeriod);

+  }

+

+  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

+  )

+{

+  UINT64  TimerCount;

+  UINT32  TimerFrequency;

+  UINTN   DivideValue = 1;

+

+  if (TimerPeriod == 0) {

+    //

+    // Disable timer interrupt for a TimerPeriod of 0

+    //

+    DisableApicTimerInterrupt();

+  } else {

+    TimerFrequency = PcdGet32(PcdFSBClock) / DivideValue;

+

+    //

+    // Convert TimerPeriod into local APIC counts

+    //

+    // TimerPeriod is in 100ns

+    // TimerPeriod/10000000 will be in seconds.

+    TimerCount = DivU64x32 (MultU64x32 (TimerPeriod, TimerFrequency),

+                            10000000);

+

+    // Check for overflow

+    if (TimerCount > MAX_UINT32) {

+      TimerCount = MAX_UINT32;

+      /* TimerPeriod = (MAX_UINT32 / TimerFrequency) * 10000000; */

+      TimerPeriod = 429496730;

+    }

+

+    //

+    // Program the timer with the new count value

+    //

+    InitializeApicTimer(DivideValue, TimerCount, TRUE, LOCAL_APIC_TIMER_VECTOR);

+

+    //

+    // Enable timer interrupt

+    //

+    EnableApicTimerInterrupt();

+  }

+  //

+  // 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 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

+  )

+{

+  EFI_TPL     OriginalTPL;

+

+  if (GetApicTimerInterruptState()) {

+    //

+    // Invoke the registered handler

+    //

+    OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);

+

+    if (mTimerNotifyFunction != NULL) {

+      //

+      // @bug : This does not handle missed timer interrupts

+      //

+      mTimerNotifyFunction (mTimerPeriod);

+    }

+

+    gBS->RestoreTPL (OriginalTPL);

+  } else {

+    return EFI_UNSUPPORTED;

+  }

+

+  return EFI_SUCCESS;

+}

+

+/**

+  Initialize the Timer Architectural Protocol driver

+

+  @param ImageHandle     ImageHandle of the loaded driver

+  @param SystemTable     Pointer to the System Table

+

+  @retval EFI_SUCCESS            Timer Architectural Protocol created

+  @retval EFI_OUT_OF_RESOURCES   Not enough resources available to initialize driver.

+  @retval EFI_DEVICE_ERROR       A device error occurred attempting to initialize the driver.

+

+**/

+EFI_STATUS

+EFIAPI

+TimerDriverInitialize (

+  IN EFI_HANDLE        ImageHandle,

+  IN EFI_SYSTEM_TABLE  *SystemTable

+  )

+{

+  EFI_STATUS  Status;

+

+  //

+  // Initialize the pointer to our notify function.

+  //

+  mTimerNotifyFunction = NULL;

+

+  //

+  // Make sure the Timer Architectural Protocol is not already installed in the system

+  //

+  ASSERT_PROTOCOL_ALREADY_INSTALLED (NULL, &gEfiTimerArchProtocolGuid);

+

+  //

+  // Find the CPU architectural protocol.

+  //

+  Status = gBS->LocateProtocol (&gEfiCpuArchProtocolGuid, NULL, (VOID **) &mCpu);

+  ASSERT_EFI_ERROR (Status);

+

+  //

+  // Force the timer to be disabled

+  //

+  Status = TimerDriverSetTimerPeriod (&mTimer, 0);

+  ASSERT_EFI_ERROR (Status);

+

+  //

+  // Install interrupt handler for Local APIC Timer

+  //

+  Status = mCpu->RegisterInterruptHandler (mCpu, LOCAL_APIC_TIMER_VECTOR,

+                                           TimerInterruptHandler);

+  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);

+

+  //

+  // Install the Timer Architectural Protocol onto a new handle

+  //

+  Status = gBS->InstallMultipleProtocolInterfaces (

+                  &mTimerHandle,

+                  &gEfiTimerArchProtocolGuid, &mTimer,

+                  NULL

+                  );

+  ASSERT_EFI_ERROR (Status);

+

+  return Status;

+}

+

diff --git a/OvmfPkg/XenTimerDxe/XenTimerDxe.h b/OvmfPkg/XenTimerDxe/XenTimerDxe.h
new file mode 100644
index 0000000000..e0a3d95fd0
--- /dev/null
+++ b/OvmfPkg/XenTimerDxe/XenTimerDxe.h
@@ -0,0 +1,177 @@
+/** @file

+  Private data structures

+

+Copyright (c) 2005 - 2018, Intel Corporation. All rights reserved.<BR>

+Copyright (c) 2019, Citrix Systems, Inc.

+

+SPDX-License-Identifier: BSD-2-Clause-Patent

+**/

+

+#ifndef _TIMER_H_

+#define _TIMER_H_

+

+#include <PiDxe.h>

+

+#include <Protocol/Cpu.h>

+#include <Protocol/Timer.h>

+

+#include <Register/LocalApic.h>

+

+#include <Library/UefiBootServicesTableLib.h>

+#include <Library/BaseLib.h>

+#include <Library/DebugLib.h>

+#include <Library/LocalApicLib.h>

+#include <Library/PcdLib.h>

+

+// The default timer tick duration is set to 10 ms = 100000 100 ns units

+//

+#define DEFAULT_TIMER_TICK_DURATION 100000

+

+//

+// The Timer Vector use for interrupt

+//

+#define LOCAL_APIC_TIMER_VECTOR 32

+

+//

+// Function Prototypes

+//

+/**

+  Initialize the Timer Architectural Protocol driver

+

+  @param ImageHandle     ImageHandle of the loaded driver

+  @param SystemTable     Pointer to the System Table

+

+  @retval EFI_SUCCESS            Timer Architectural Protocol created

+  @retval EFI_OUT_OF_RESOURCES   Not enough resources available to initialize driver.

+  @retval EFI_DEVICE_ERROR       A device error occurred attempting to initialize the driver.

+

+**/

+EFI_STATUS

+EFIAPI

+TimerDriverInitialize (

+  IN EFI_HANDLE        ImageHandle,

+  IN EFI_SYSTEM_TABLE  *SystemTable

+  )

+;

+

+/**

+

+  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 NotifyFunction  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

+TimerDriverRegisterHandler (

+  IN EFI_TIMER_ARCH_PROTOCOL  *This,

+  IN EFI_TIMER_NOTIFY         NotifyFunction

+  )

+;

+

+/**

+

+  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

+  )

+;

+

+/**

+

+  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

+  )

+;

+

+/**

+

+  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

+  )

+;

+

+#endif

diff --git a/OvmfPkg/XenTimerDxe/XenTimerDxe.inf b/OvmfPkg/XenTimerDxe/XenTimerDxe.inf
new file mode 100644
index 0000000000..add1d01bbf
--- /dev/null
+++ b/OvmfPkg/XenTimerDxe/XenTimerDxe.inf
@@ -0,0 +1,42 @@
+## @file

+# Local APIC timer driver that provides Timer Arch protocol.

+#

+# Copyright (c) 2005 - 2019, Intel Corporation. All rights reserved.<BR>

+# Copyright (c) 2019, Citrix Systems, Inc.

+#

+# SPDX-License-Identifier: BSD-2-Clause-Patent

+#

+##

+

+[Defines]

+  INF_VERSION                    = 0x00010005

+  BASE_NAME                      = XenTimerDxe

+  FILE_GUID                      = 52fe8196-f9de-4d07-b22f-51f77a0e7c41

+  MODULE_TYPE                    = DXE_DRIVER

+  VERSION_STRING                 = 1.0

+

+  ENTRY_POINT                    = TimerDriverInitialize

+

+[Packages]

+  MdePkg/MdePkg.dec

+  UefiCpuPkg/UefiCpuPkg.dec

+  OvmfPkg/OvmfPkg.dec

+

+[LibraryClasses]

+  UefiBootServicesTableLib

+  BaseLib

+  DebugLib

+  UefiDriverEntryPoint

+  LocalApicLib

+

+[Sources]

+  XenTimerDxe.h

+  XenTimerDxe.c

+

+[Protocols]

+  gEfiCpuArchProtocolGuid       ## CONSUMES

+  gEfiTimerArchProtocolGuid     ## PRODUCES

+[Pcd]

+  gEfiMdePkgTokenSpaceGuid.PcdFSBClock  ## CONSUMES

+[Depex]

+  gEfiCpuArchProtocolGuid