ArmPkg/Drivers/TimerDxe: Improve Timer initialisation.

- Registering a interrupt handler implicitly enables said interrupt. This
  is in the UEFI Spec. No need to enable the interrupts a second time.
- Make sure the Timer is completely disabled before configuring it. Only
  enable after configuration is complete.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Olivier Martin <olivier.martin@arm.com>


git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@14433 6f19259b-4bc3-4df7-8a09-765794883524

1 files changed, 15 insertions, 18 deletions

diff --git a/ArmPkg/Drivers/TimerDxe/TimerDxe.c b/ArmPkg/Drivers/TimerDxe/TimerDxe.c
index cbc34e8e41..dabcc8313b 100644
--- a/ArmPkg/Drivers/TimerDxe/TimerDxe.c
+++ b/ArmPkg/Drivers/TimerDxe/TimerDxe.c
@@ -1,15 +1,15 @@
 /** @file

   Timer Architecture Protocol driver of the ARM flavor

 

-  Copyright (c) 2011 ARM Ltd. All rights reserved.<BR>

-  

-  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                                            

+  Copyright (c) 2011-2013 ARM Ltd. All rights reserved.<BR>

+

+  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.             

+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,

+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.

 

 **/

 

@@ -336,6 +336,10 @@ TimerInitialize (
   ASSERT_EFI_ERROR (Status);

 

   // Disable the timer

+  TimerCtrlReg = ArmArchTimerGetTimerCtrlReg ();

+  TimerCtrlReg |= ARM_ARCH_TIMER_IMASK;

+  TimerCtrlReg &= ~ARM_ARCH_TIMER_ENABLE;

+  ArmArchTimerSetTimerCtrlReg (TimerCtrlReg);

   Status = TimerDriverSetTimerPeriod (&gTimer, 0);

   ASSERT_EFI_ERROR (Status);

 

@@ -349,11 +353,6 @@ TimerInitialize (
   Status = gInterrupt->RegisterInterruptSource (gInterrupt, PcdGet32 (PcdArmArchTimerIntrNum), TimerInterruptHandler);

   ASSERT_EFI_ERROR (Status);

 

-  // Unmask timer interrupts

-  TimerCtrlReg = ArmArchTimerGetTimerCtrlReg ();

-  TimerCtrlReg &= ~ARM_ARCH_TIMER_IMASK;

-  ArmArchTimerSetTimerCtrlReg (TimerCtrlReg);

-

   // Set up default timer

   Status = TimerDriverSetTimerPeriod (&gTimer, FixedPcdGet32(PcdTimerPeriod)); // TIMER_DEFAULT_PERIOD

   ASSERT_EFI_ERROR (Status);

@@ -366,11 +365,9 @@ TimerInitialize (
                   );

   ASSERT_EFI_ERROR(Status);

 

-  // enable Secure timer interrupts

-  Status = gInterrupt->EnableInterruptSource (gInterrupt, PcdGet32 (PcdArmArchTimerSecIntrNum));

-

-  // enable NonSecure timer interrupts

-  Status = gInterrupt->EnableInterruptSource (gInterrupt, PcdGet32 (PcdArmArchTimerIntrNum));

+  // Everything is ready, unmask and enable timer interrupts

+  TimerCtrlReg = ARM_ARCH_TIMER_ENABLE;

+  ArmArchTimerSetTimerCtrlReg (TimerCtrlReg);

 

   // Register for an ExitBootServicesEvent

   Status = gBS->CreateEvent (EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_NOTIFY, ExitBootServicesEvent, NULL, &EfiExitBootServicesEvent);