/**
 * @file RomLayoutDxe.h
 *
 * @brief RomLayoutDxe - UEFI DXE driver for locating ROM layout via HOB and
 *        registering a UBA (Unified Board Architecture) setup configuration
 *        protocol for the NeonCityFPGA platform.
 *
 * MODULE TYPE: DXE Driver
 * UEFI PHASE:  DXE (Driver Execution Environment)
 *
 * PURPOSE:
 *   This driver is part of Lenovo's UBA (Unified Board Architecture) framework.
 *   It performs the following at entry:
 *     1. Locates the HOB (Hand-Off Block) list from the UEFI System Table's
 *        configuration table array by matching the EFI_HOB_LIST_GUID.
 *     2. Locates a UBA board-type protocol (specific to NeonCityFPGA) using
 *        gBS->LocateProtocol().
 *     3. Installs a new protocol interface (with GUID cd1f9574-dd03-4196-96ad-4965146f9665)
 *        via a function on the located UBA protocol interface, passing a
 *        UBA_SETUP_CONFIG_DATA structure (signature "PSET", version 1, 0x48c bytes).
 *     4. Provides debug output via the UEFI DebugLib protocol accessed through
 *        the UEFI Boot Services table (gBS).
 *
 * DEPENDENCIES (Protocols consumed):
 *   - UBA NeonCityFPGA Board-Type Protocol (GUID: e03e0d46-5263-4845-b0a4-58d57b3177e2)
 *     This protocol is located to register the setup configuration.
 *   - EFI_HOB_LIST_GUID (7739f24c-93d7-11d4-9a3a-0090273fc14d)
 *     Used to locate the HOB list from the system configuration table.
 *   - UEFI Debug Library Protocol (implicit via gBS)
 *
 * DEPENDENCIES (Protocols produced):
 *   - UBA NeonCityFPGA Setup Config Protocol
 *     (GUID: cd1f9574-dd03-4196-96ad-4965146f9665)
 *     Registered with a UBA_SETUP_CONFIG_DATA interface.
 *
 * HARDWARE ACCESS:
 *   - CMOS ports 0x70/0x71: Read debug level setting mask from CMOS register 0x4B
 *   - MMIO 0xFDAF0490: On some platforms, reads a board configuration register
 *                       to determine debug verbosity level.
 *
 * LIBRARY DEPENDENCIES:
 *   - UefiBootServicesTableLib (gImageHandle, gST, gBS)
 *   - UefiRuntimeServicesTableLib (gRT)
 *   - DxeHobLib (HOB list parsing)
 *   - BaseLib (unaligned read: ReadUnaligned64)
 *   - DebugLib (DEBUG macro via CmosDebugLevelProvider)
 *
 * @note This module is index 0000 in the BIOS FFS - it is one of the first
 *       DXE drivers dispatched.
 */

#ifndef _ROM_LAYOUT_DXE_H_
#define _ROM_LAYOUT_DXE_H_

#include "../uefi_headers/Uefi.h"

// ============================================================================
// GUID Definitions
// ===========================================================================/

///
/// EFI_HOB_LIST_GUID - GUID used to locate the HOB list in the system
/// configuration table.
/// {7739F24C-93D7-11D4-9A3A-0090273FC14D}
///
#define EFI_HOB_LIST_GUID \
  { 0x7739F24C, 0x93D7, 0x11D4, { 0x9A, 0x3A, 0x00, 0x90, 0x27, 0x3F, 0xC1, 0x4D } }

///
/// UBA_NEONCITYFPGA_BOARD_TYPE_PROTOCOL_GUID
/// Protocol GUID used with gBS->LocateProtocol() to obtain the UBA board-type
/// protocol interface for the NeonCityFPGA platform.
/// This protocol's interface has a function at offset 0x10 (16) that registers
/// the setup configuration data.
/// {E03E0D46-5263-4845-B0A4-58D57B3177E2}
///
#define UBA_NEONCITYFPGA_BOARD_TYPE_PROTOCOL_GUID \
  { 0xE03E0D46, 0x5263, 0x4845, { 0xB0, 0xA4, 0x58, 0xD5, 0x7B, 0x31, 0x77, 0xE2 } }

///
/// UBA_NEONCITYFPGA_SETUP_CONFIG_PROTOCOL_GUID
/// Protocol GUID that is registered by this driver during its entry point.
/// This protocol is installed via the board-type protocol's registration
/// function and represents the setup configuration for NeonCityFPGA.
/// {CD1F9574-DD03-4196-96AD-4965146F9665}
///
#define UBA_NEONCITYFPGA_SETUP_CONFIG_PROTOCOL_GUID \
  { 0xCD1F9574, 0xDD03, 0x4196, { 0x96, 0xAD, 0x49, 0x65, 0x14, 0x6F, 0x96, 0x65 } }

// ============================================================================
// Structure Definitions
// ===========================================================================/

///
/// UBA_SETUP_CONFIG_DATA
/// Structure passed to the UBA board-type protocol to register the setup
/// configuration data for the NeonCityFPGA platform.
///
/// The signature is "PSET" (little-endian: 'P','S','E','T'), which is "SETP"
/// in big-endian -- an encoding of "SETUP" with the last character dropped.
///
typedef struct {
  ///
  /// Signature = "PSET" (0x54455350 in little-endian).
  ///
  UINT32    Signature;
  ///
  /// Version of this structure. Currently = 1.
  ///
  UINT32    Version;
  ///
  /// Total size of the setup configuration data blob. Size = 0x48c (1164) bytes.
  ///
  UINT64    Size;
  ///
  /// Additional size field (duplicate of Size for alignment/padding).
  ///
  UINT64    SizeDuplicate;
} UBA_SETUP_CONFIG_DATA;

///
/// UBA_SETUP_CONFIG_FIXED_SIZE
/// The fixed size of the configuration data associated with this module.
///
#define UBA_SETUP_CONFIG_FIXED_SIZE  0x48c

///
/// UBA_SETUP_CONFIG_VERSION
/// Current version of the UBA setup config structure.
///
#define UBA_SETUP_CONFIG_VERSION     0x1

///
/// CMOS debug level register. Port 0x70 selects the CMOS register;
/// port 0x71 reads/writes the value.
/// Register 0x4B is used for debug level control.
///
#define CMOS_DEBUG_LEVEL_REGISTER    0x4B

///
/// CMOS index port
///
#define RTC_INDEX_PORT               0x70

///
/// CMOS data port
///
#define RTC_DATA_PORT                0x71

///
/// Board configuration MMIO register address (used for debug level fallback).
///
#define BOARD_CONFIG_MMIO_ADDR       0xFDAF0490ULL

///
/// Debug message severity mask. Used with the DebugLib protocol.
///
#define DEBUG_INFO                   0x80000000

// ============================================================================
// Global Variable Declarations
// ===========================================================================/

//
// UEFI Boot Services Table pointer (cached by UefiBootServicesTableLib).
//
extern EFI_SYSTEM_TABLE   *gST;
extern EFI_BOOT_SERVICES  *gBS;
extern EFI_RUNTIME_SERVICES *gRT;
extern EFI_HANDLE         gImageHandle;

///
/// Pointer to the HOB list, obtained from the system configuration table
/// by searching for the EFI_HOB_LIST_GUID entry.
///
extern VOID               *gHobList;

// ============================================================================
// Function Declarations
// ===========================================================================/

/**
 * Module entry point for RomLayoutDxe.
 *
 * Initializes UEFI global variables (gImageHandle, gST, gBS, gRT), locates the
 * HOB list, prints a debug banner, locates the UBA
 * NeonCityFPGA board-type protocol, and registers the setup configuration data
 * by calling the protocol's registration function.
 *
 * @param[in] ImageHandle  The firmware-allocated handle for this driver image.
 * @param[in] SystemTable  A pointer to the EFI System Table.
 *
 * @return EFI_SUCCESS     The protocol was successfully registered.
 * @return Other           The protocol could not be located or registered.
 */
EFI_STATUS
EFIAPI
_ModuleEntryPoint (
  IN EFI_HANDLE        ImageHandle,
  IN EFI_SYSTEM_TABLE  *SystemTable
  );

/**
 * Locates the HOB (Hand-Off Block) list from the UEFI System Table's
 * configuration table array.
 *
 * Iterates through SystemTable->ConfigurationTable[] looking for an entry
 * whose VendorGuid matches EFI_HOB_LIST_GUID (7739f24c-93d7-11d4-9a3a-0090273fc14d).
 * The comparison is done by matching the first 8 bytes and second 8 bytes of
 * the GUID separately.
 *
 * Results are cached in the global variable qword_BC0 (gHobList).
 *
 * @param[in] ImageHandle  The driver image handle (passed through from entry,
 *                         may be unused).
 *
 * @return Pointer to the HOB list, or NULL if not found.
 */
VOID *
GetHobList (
  IN EFI_HANDLE  ImageHandle
  );

/**
 * Compares a GUID against the EFI_HOB_LIST_GUID by comparing its first 8 bytes
 * and second 8 bytes independently.
 *
 * Uses ReadUnaligned64() to perform the comparison.
 *
 * @param[in] ImageHandle  Unused parameter.
 * @param[in] GuidPtr      Pointer to the GUID to compare.
 *
 * @retval TRUE   The GUID matches EFI_HOB_LIST_GUID.
 * @retval FALSE  The GUID does not match.
 */
BOOLEAN
IsHobListGuid (
  IN EFI_HANDLE  ImageHandle,
  IN EFI_GUID    *GuidPtr
  );

/**
 * Debug print function (wraps the UEFI DebugLib protocol).
 *
 * Resolves the DebugLib protocol interface via the UEFI Boot Services table
 * and calls its output function if the debug level determined by CMOS register
 * 0x4B matches the requested severity mask.
 *
 * @param[in] ErrorLevel  The debug error level mask (e.g., DEBUG_INFO = 0x80000000).
 * @param[in] Format      A format string for the debug message.
 * @param[in] ...         Variable arguments for the format string.
 *
 * @return The return value from the DebugLib protocol's output function,
 *         or 0 if the protocol is not available.
 */
UINTN
EFIAPI
DebugPrint (
  IN UINTN       ErrorLevel,
  IN CONST CHAR8 *Format,
  ...
  );

/**
 * ASSERT assertion failure handler.
 *
 * Called when a runtime assertion fails. Resolves the DebugLib protocol
 * and calls its assertion failure handler.
 *
 * @param[in] FileName     Source file name where the assertion occurred.
 * @param[in] LineNumber   Line number of the assertion.
 * @param[in] Description  Description of the failed assertion.
 *
 * @return 0 if the DebugLib protocol is not available.
 */
UINTN
DebugAssert (
  IN CONST CHAR8  *FileName,
  IN UINTN        LineNumber,
  IN CONST CHAR8  *Description
  );

/**
 * Returns the UEFI status code for "Not Found".
 *
 * This is a trivial leaf function that returns 0x800000000000000E (EFI_NOT_FOUND).
 *
 * @return EFI_NOT_FOUND (0x800000000000000E).
 */
EFI_STATUS
ReturnNotFound (
  VOID
  );

/**
 * Reads an unaligned 64-bit value from memory.
 *
 * Wraps the BaseLib ReadUnaligned64() function with a NULL pointer check.
 *
 * @param[in] Buffer  Pointer to the memory to read. Must not be NULL.
 *
 * @return The 64-bit value read from the given address.
 */
UINT64
ReadUnaligned64 (
  IN CONST VOID  *Buffer
  );

// ============================================================================
// UBA Board-Type Protocol Interface
// ===========================================================================/

///
/// UBA_NEONCITYFPGA_BOARD_TYPE_PROTOCOL
///
/// The protocol interface obtained via gBS->LocateProtocol() using the GUID
/// UBA_NEONCITYFPGA_BOARD_TYPE_PROTOCOL_GUID.
///
/// This protocol is used to register platform-specific setup configuration
/// data. The registration function is at offset 0x10 within the interface
/// structure.
///
typedef struct {
  ///
  /// Unknown fields at offsets 0x00-0x0F (may contain protocol revision,
  /// header, or other methods).
  ///
  UINT64   Reserved0;
  UINT64   Reserved1;
  ///
  /// Function at offset 0x10. Registers the setup configuration data.
  ///
  /// @param[in] This            Pointer to the UBA board-type protocol interface.
  /// @param[in] ProtocolGuid    GUID of the protocol to register
  ///                            (UBA_NEONCITYFPGA_SETUP_CONFIG_PROTOCOL_GUID).
  /// @param[in] ConfigData      Pointer to the UBA_SETUP_CONFIG_DATA structure.
  /// @param[in] ConfigDataSize  Size of the configuration data structure in bytes.
  ///
  /// @return EFI_STATUS.
  ///
  EFI_STATUS
  (EFIAPI *RegisterSetupConfig) (
    IN VOID                  *This,
    IN EFI_GUID              *ProtocolGuid,
    IN UBA_SETUP_CONFIG_DATA *ConfigData,
    IN UINT64                ConfigDataSize
    );
} UBA_NEONCITYFPGA_BOARD_TYPE_PROTOCOL;

#endif /* _ROM_LAYOUT_DXE_H_ */