/** @file
*  Generic Timer Description Table (GTDT)
*
*  Copyrignt (c) 2020, Linaro Limited. All rights reserved.
*
*  SPDX-License-Identifier: BSD-2-Clause-Patent
**/

#include <Library/AcpiLib.h>
#include <Library/PcdLib.h>
#include <IndustryStandard/Acpi.h>
#include <IndustryStandard/SbsaQemuAcpi.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     0xFFFFFFFFFFFFFFFF
#endif

#define GTDT_TIMER_EDGE_TRIGGERED   EFI_ACPI_6_3_GTDT_TIMER_FLAG_TIMER_INTERRUPT_MODE
#define GTDT_TIMER_LEVEL_TRIGGERED  0
#define GTDT_TIMER_ACTIVE_LOW       EFI_ACPI_6_3_GTDT_TIMER_FLAG_TIMER_INTERRUPT_POLARITY
#define GTDT_TIMER_ACTIVE_HIGH      0
#define GTDT_TIMER_ALWAYS_ON        EFI_ACPI_6_3_GTDT_TIMER_FLAG_ALWAYS_ON_CAPABILITY

#define GTDT_GTIMER_FLAGS           (GTDT_TIMER_ACTIVE_LOW | \
                                     GTDT_TIMER_LEVEL_TRIGGERED | \
                                     GTDT_TIMER_ALWAYS_ON)

#define SBSA_PLATFORM_WATCHDOG_COUNT    1
#define SBSA_PLATFORM_TIMER_COUNT       (SBSA_PLATFORM_WATCHDOG_COUNT)

#define SBSAQEMU_WDT_REFRESH_FRAME_BASE      0x50010000
#define SBSAQEMU_WDT_CONTROL_FRAME_BASE      0x50011000
#define SBSAQEMU_WDT_IRQ                     48

#define GTDT_WDTIMER_EDGE_TRIGGERED   EFI_ACPI_6_3_GTDT_SBSA_GENERIC_WATCHDOG_FLAG_TIMER_INTERRUPT_MODE
#define GTDT_WDTIMER_LEVEL_TRIGGERED  0
#define GTDT_WDTIMER_ACTIVE_LOW       EFI_ACPI_6_3_GTDT_SBSA_GENERIC_WATCHDOG_FLAG_TIMER_INTERRUPT_POLARITY
#define GTDT_WDTIMER_ACTIVE_HIGH      0

#define GTDT_WDTIMER_FLAGS          (GTDT_WDTIMER_ACTIVE_HIGH | GTDT_WDTIMER_LEVEL_TRIGGERED)

#define EFI_ACPI_6_3_SBSA_GENERIC_WATCHDOG_STRUCTURE_INIT(       \
  RefreshFramePhysicalAddress, ControlFramePhysicalAddress,      \
  WatchdogTimerGSIV, WatchdogTimerFlags)                         \
  {                                                              \
    EFI_ACPI_6_3_GTDT_SBSA_GENERIC_WATCHDOG,                     \
    sizeof(EFI_ACPI_6_3_GTDT_SBSA_GENERIC_WATCHDOG_STRUCTURE),   \
    EFI_ACPI_RESERVED_WORD,                                      \
    RefreshFramePhysicalAddress,                                 \
    ControlFramePhysicalAddress,                                 \
    WatchdogTimerGSIV,                                           \
    WatchdogTimerFlags                                           \
  }

  #pragma pack (1)

  typedef struct {
    EFI_ACPI_6_3_GENERIC_TIMER_DESCRIPTION_TABLE          Gtdt;
    EFI_ACPI_6_3_GTDT_SBSA_GENERIC_WATCHDOG_STRUCTURE     Gwdt;
  } GENERIC_TIMER_DESCRIPTION_TABLES;

  #pragma pack ()

  GENERIC_TIMER_DESCRIPTION_TABLES Gtdt = {
    {
      SBSAQEMU_ACPI_HEADER(
        EFI_ACPI_6_3_GENERIC_TIMER_DESCRIPTION_TABLE_SIGNATURE,
        GENERIC_TIMER_DESCRIPTION_TABLES,
        EFI_ACPI_6_3_GENERIC_TIMER_DESCRIPTION_TABLE_REVISION
      ),
      SYSTEM_TIMER_BASE_ADDRESS,                    // UINT64  PhysicalAddress
      0,                                            // UINT32  Reserved
      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
      0xFFFFFFFFFFFFFFFF,                           // UINT64  CntReadBasePhysicalAddress
      SBSA_PLATFORM_TIMER_COUNT,                    // UINT32  PlatformTimerCount
      sizeof(EFI_ACPI_6_3_GENERIC_TIMER_DESCRIPTION_TABLE),
                                                    // UINT32  PlatformTimerOffset
      0,                                            // UINT32  VirtualPL2TimerGSIV
      0                                             // UINT32  VirtualPL2TimerFlags
    },
    EFI_ACPI_6_3_SBSA_GENERIC_WATCHDOG_STRUCTURE_INIT(
    SBSAQEMU_WDT_REFRESH_FRAME_BASE,
    SBSAQEMU_WDT_CONTROL_FRAME_BASE,
    SBSAQEMU_WDT_IRQ,
    GTDT_WDTIMER_FLAGS
    )
  };

// Reference the table being generated to prevent the optimizer from removing the
// data structure from the executable
VOID* CONST ReferenceAcpiTable = &Gtdt;
