/** @file
*  Generic Timer Description Table (GTDT)
*
*  Copyright (c) 2012 - 2014, ARM Limited. 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 "ArmPlatform.h"
#include <Library/AcpiLib.h>
#include <Library/PcdLib.h>
#include <IndustryStandard/Acpi.h>

#define GTDT_GLOBAL_FLAGS_MAPPED      EFI_ACPI_5_0_GTDT_GLOBAL_FLAG_MEMORY_MAPPED_BLOCK_PRESENT
#define GTDT_GLOBAL_FLAGS_NOT_MAPPED  0
#define GTDT_GLOBAL_FLAGS_EDGE        EFI_ACPI_5_0_GTDT_GLOBAL_FLAG_INTERRUPT_MODE
#define GTDT_GLOBAL_FLAGS_LEVEL       0

// Note: We could have a build flag that switches between memory mapped/non-memory mapped timer
#ifdef SYSTEM_TIMER_BASE_ADDRESS
  #define GTDT_GLOBAL_FLAGS             (GTDT_GLOBAL_FLAGS_MAPPED | GTDT_GLOBAL_FLAGS_LEVEL)
#else
  #define GTDT_GLOBAL_FLAGS             (GTDT_GLOBAL_FLAGS_NOT_MAPPED | GTDT_GLOBAL_FLAGS_LEVEL)
  #define SYSTEM_TIMER_BASE_ADDRESS     0
#endif

#define GTDT_TIMER_EDGE_TRIGGERED   (1 << EFI_ACPI_5_0_GTDT_TIMER_FLAG_TIMER_INTERRUPT_MODE)
#define GTDT_TIMER_LEVEL_TRIGGERED  (0 << EFI_ACPI_5_0_GTDT_TIMER_FLAG_TIMER_INTERRUPT_MODE)
#define GTDT_TIMER_ACTIVE_LOW       (1 << EFI_ACPI_5_0_GTDT_TIMER_FLAG_TIMER_INTERRUPT_POLARITY)
#define GTDT_TIMER_ACTIVE_HIGH      (0 << EFI_ACPI_5_0_GTDT_TIMER_FLAG_TIMER_INTERRUPT_POLARITY)

#define GTDT_GTIMER_FLAGS           (GTDT_TIMER_ACTIVE_LOW | GTDT_TIMER_LEVEL_TRIGGERED)

EFI_ACPI_5_0_GENERIC_TIMER_DESCRIPTION_TABLE Gtdt = {
    ARM_ACPI_HEADER(
      EFI_ACPI_5_0_GENERIC_TIMER_DESCRIPTION_TABLE_SIGNATURE,
      EFI_ACPI_5_0_GENERIC_TIMER_DESCRIPTION_TABLE,
      EFI_ACPI_5_0_GENERIC_TIMER_DESCRIPTION_TABLE_REVISION
    ),
  SYSTEM_TIMER_BASE_ADDRESS,                    // UINT64  PhysicalAddress
  GTDT_GLOBAL_FLAGS,                            // UINT32  GlobalFlags
  FixedPcdGet32 (PcdArmArchTimerSecIntrNum),    // UINT32  SecurePL1TimerGSIV
  GTDT_GTIMER_FLAGS,                            // UINT32  SecurePL1TimerFlags
  FixedPcdGet32 (PcdArmArchTimerIntrNum),       // UINT32  NonSecurePL1TimerGSIV
  GTDT_GTIMER_FLAGS,                            // UINT32  NonSecurePL1TimerFlags
  FixedPcdGet32 (PcdArmArchTimerVirtIntrNum),   // UINT32  VirtualTimerGSIV
  GTDT_GTIMER_FLAGS,                            // UINT32  VirtualTimerFlags
  FixedPcdGet32 (PcdArmArchTimerHypIntrNum),    // UINT32  NonSecurePL2TimerGSIV
  GTDT_GTIMER_FLAGS                             // UINT32  NonSecurePL2TimerFlags
};


VOID*
ReferenceAcpiTable (
  VOID
  )
{
  //
  // Reference the table being generated to prevent the optimizer from removing the
  // data structure from the exeutable
  //
  return (VOID*)&Gtdt;
}