path: root/include/boot/efi.h

#pragma once
// ============================================================================
// efi.h - Minimal UEFI type and protocol definitions
//
// Only what we need for our boot loader. No external dependencies (like gnu-efi).
// Reference: UEFI Specification 2.10, https://uefi.org/specs/UEFI/2.10/
// I generate it with Cloude, because i don't want to manually rewrite whole spec
// ============================================================================

#include <stdint.h>
#include <stddef.h>

// ── Base types ─────────────────────────────────────────────────────────────

typedef uint64_t        UINTN;
typedef int64_t         INTN;
typedef uint64_t        EFI_STATUS;
typedef void*           EFI_HANDLE;
typedef void*           EFI_EVENT;
typedef uint64_t        EFI_PHYSICAL_ADDRESS;
typedef uint64_t        EFI_VIRTUAL_ADDRESS;
typedef wchar_t         CHAR16;  // With -fshort-wchar, wchar_t is 16-bit
typedef uint8_t         BOOLEAN;

#define TRUE  1
#define FALSE 0
#define IN
#define OUT
#define OPTIONAL
#define EFIAPI

// ── Status codes ───────────────────────────────────────────────────────────

#define EFI_SUCCESS              0ULL
#define EFI_ERROR_BIT            (1ULL << 63)
#define EFI_LOAD_ERROR           (EFI_ERROR_BIT | 1)
#define EFI_INVALID_PARAMETER    (EFI_ERROR_BIT | 2)
#define EFI_UNSUPPORTED          (EFI_ERROR_BIT | 3)
#define EFI_BAD_BUFFER_SIZE      (EFI_ERROR_BIT | 4)
#define EFI_BUFFER_TOO_SMALL     (EFI_ERROR_BIT | 5)
#define EFI_NOT_FOUND            (EFI_ERROR_BIT | 14)

#define EFI_ERROR(status) ((status) & EFI_ERROR_BIT)

// ── GUIDs ──────────────────────────────────────────────────────────────────

struct EFI_GUID {
    uint32_t Data1;
    uint16_t Data2;
    uint16_t Data3;
    uint8_t  Data4[8];
};

#define EFI_GRAPHICS_OUTPUT_PROTOCOL_GUID \
    { 0x9042A9DE, 0x23DC, 0x4A38, { 0x96, 0xFB, 0x7A, 0xDE, 0xD0, 0x80, 0x51, 0x6A } }

#define EFI_SIMPLE_FILE_SYSTEM_PROTOCOL_GUID \
    { 0x964E5B22, 0x6459, 0x11D2, { 0x8E, 0x39, 0x00, 0xA0, 0xC9, 0x69, 0x72, 0x3B } }

#define EFI_LOADED_IMAGE_PROTOCOL_GUID \
    { 0x5B1B31A1, 0x9562, 0x11D2, { 0x8E, 0x3F, 0x00, 0xA0, 0xC9, 0x69, 0x72, 0x3B } }

#define EFI_FILE_INFO_ID \
    { 0x09576E92, 0x6D3F, 0x11D2, { 0x8E, 0x39, 0x00, 0xA0, 0xC9, 0x69, 0x72, 0x3B } }

#define EFI_ACPI_20_TABLE_GUID \
    { 0x8868E871, 0xE4F1, 0x11D3, { 0xBC, 0x22, 0x00, 0x80, 0xC7, 0x3C, 0x88, 0x81 } }

#define EFI_DTB_TABLE_GUID \
    { 0xB1B621D5, 0xF19C, 0x41A5, { 0x83, 0x0B, 0xD9, 0x15, 0x2C, 0x69, 0xAA, 0xE0 } }

// ── Memory types ───────────────────────────────────────────────────────────

typedef uint32_t EFI_MEMORY_TYPE;
#define EfiReservedMemoryType       0
#define EfiLoaderCode               1
#define EfiLoaderData               2
#define EfiBootServicesCode         3
#define EfiBootServicesData         4
#define EfiRuntimeServicesCode      5
#define EfiRuntimeServicesData      6
#define EfiConventionalMemory       7
#define EfiUnusableMemory           8
#define EfiACPIReclaimMemory        9
#define EfiACPIMemoryNVS            10
#define EfiMemoryMappedIO           11
#define EfiMemoryMappedIOPortSpace  12
#define EfiPalCode                  13
#define EfiPersistentMemory         14
#define EfiMaxMemoryType            15

typedef uint32_t EFI_ALLOCATE_TYPE;
#define AllocateAnyPages    0
#define AllocateMaxAddress  1
#define AllocateAddress     2

struct EFI_MEMORY_DESCRIPTOR {
    uint32_t              Type;
    EFI_PHYSICAL_ADDRESS  PhysicalStart;
    EFI_VIRTUAL_ADDRESS   VirtualStart;
    uint64_t              NumberOfPages;
    uint64_t              Attribute;
};

// ── Simple Text Output Protocol ────────────────────────────────────────────

struct EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL {
    void* Reset;
    EFI_STATUS (EFIAPI *OutputString)(
        EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL* This,
        CHAR16*                         String
    );
    void* TestString;
    void* QueryMode;
    void* SetMode;
    void* SetAttribute;
    EFI_STATUS (EFIAPI *ClearScreen)(
        EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL* This
    );
    void* SetCursorPosition;
    void* EnableCursor;
    void* Mode;
};

// ── Graphics Output Protocol ───────────────────────────────────────────────

typedef uint32_t EFI_GRAPHICS_PIXEL_FORMAT;
#define PixelRedGreenBlueReserved8BitPerColor  0
#define PixelBlueGreenRedReserved8BitPerColor  1
#define PixelBitMask                           2
#define PixelBltOnly                           3

struct EFI_PIXEL_BITMASK {
    uint32_t RedMask;
    uint32_t GreenMask;
    uint32_t BlueMask;
    uint32_t ReservedMask;
};

struct EFI_GRAPHICS_OUTPUT_MODE_INFORMATION {
    uint32_t                  Version;
    uint32_t                  HorizontalResolution;
    uint32_t                  VerticalResolution;
    EFI_GRAPHICS_PIXEL_FORMAT PixelFormat;
    EFI_PIXEL_BITMASK         PixelInformation;
    uint32_t                  PixelsPerScanLine;
};

struct EFI_GRAPHICS_OUTPUT_PROTOCOL_MODE {
    uint32_t                              MaxMode;
    uint32_t                              Mode;
    EFI_GRAPHICS_OUTPUT_MODE_INFORMATION* Info;
    UINTN                                 SizeOfInfo;
    EFI_PHYSICAL_ADDRESS                  FrameBufferBase;
    UINTN                                 FrameBufferSize;
};

struct EFI_GRAPHICS_OUTPUT_PROTOCOL {
    void*                              QueryMode;
    void*                              SetMode;
    void*                              Blt;
    EFI_GRAPHICS_OUTPUT_PROTOCOL_MODE* Mode;
};

// ── File Protocol ──────────────────────────────────────────────────────────

#define EFI_FILE_MODE_READ   0x0000000000000001ULL
#define EFI_FILE_READ_ONLY   0x0000000000000001ULL

struct EFI_FILE_PROTOCOL {
    uint64_t Revision;
    EFI_STATUS (EFIAPI *Open)(
        EFI_FILE_PROTOCOL*  This,
        EFI_FILE_PROTOCOL** NewHandle,
        CHAR16*             FileName,
        uint64_t            OpenMode,
        uint64_t            Attributes
    );
    EFI_STATUS (EFIAPI *Close)(
        EFI_FILE_PROTOCOL* This
    );
    void* Delete;
    EFI_STATUS (EFIAPI *Read)(
        EFI_FILE_PROTOCOL* This,
        UINTN*             BufferSize,
        void*              Buffer
    );
    void* Write;
    void* GetPosition;
    void* SetPosition;
    EFI_STATUS (EFIAPI *GetInfo)(
        EFI_FILE_PROTOCOL* This,
        EFI_GUID*          InformationType,
        UINTN*             BufferSize,
        void*              Buffer
    );
};

struct EFI_FILE_INFO {
    uint64_t Size;
    uint64_t FileSize;
    uint64_t PhysicalSize;
    uint8_t  _time_padding[48];  // Skip EFI_TIME fields
    uint64_t Attribute;
    CHAR16   FileName[1];        // Variable length
};

// ── Simple File System Protocol ────────────────────────────────────────────

struct EFI_SIMPLE_FILE_SYSTEM_PROTOCOL {
    uint64_t Revision;
    EFI_STATUS (EFIAPI *OpenVolume)(
        EFI_SIMPLE_FILE_SYSTEM_PROTOCOL* This,
        EFI_FILE_PROTOCOL**              Root
    );
};

// ── Loaded Image Protocol ──────────────────────────────────────────────────

struct EFI_LOADED_IMAGE_PROTOCOL {
    uint32_t   Revision;
    EFI_HANDLE ParentHandle;
    void*      SystemTable;
    EFI_HANDLE DeviceHandle;
    void*      FilePath;
    void*      Reserved;
    uint32_t   LoadOptionsSize;
    void*      LoadOptions;
    void*      ImageBase;
    uint64_t   ImageSize;
    EFI_MEMORY_TYPE ImageCodeType;
    EFI_MEMORY_TYPE ImageDataType;
    void*      Unload;
};

// ── Boot Services ──────────────────────────────────────────────────────────

struct EFI_BOOT_SERVICES {
    char _hdr[24];

    // Task Priority (2)
    void* RaiseTPL;
    void* RestoreTPL;

    // Memory Services
    EFI_STATUS (EFIAPI *AllocatePages)(
        EFI_ALLOCATE_TYPE      Type,
        EFI_MEMORY_TYPE        MemoryType,
        UINTN                  Pages,
        EFI_PHYSICAL_ADDRESS*  Memory
    );
    EFI_STATUS (EFIAPI *FreePages)(
        EFI_PHYSICAL_ADDRESS Memory,
        UINTN                Pages
    );
    EFI_STATUS (EFIAPI *GetMemoryMap)(
        UINTN*                  MemoryMapSize,
        EFI_MEMORY_DESCRIPTOR*  MemoryMap,
        UINTN*                  MapKey,
        UINTN*                  DescriptorSize,
        uint32_t*               DescriptorVersion
    );
    EFI_STATUS (EFIAPI *AllocatePool)(
        EFI_MEMORY_TYPE PoolType,
        UINTN           Size,
        void**          Buffer
    );
    EFI_STATUS (EFIAPI *FreePool)(
        void* Buffer
    );

    // Event & Timer (6)
    void* CreateEvent;
    void* SetTimer;
    void* WaitForEvent;
    void* SignalEvent;
    void* CloseEvent;
    void* CheckEvent;

    // Protocol Handler (6 + 3)
    void* InstallProtocolInterface;
    void* ReinstallProtocolInterface;
    void* UninstallProtocolInterface;
    EFI_STATUS (EFIAPI *HandleProtocol)(
        EFI_HANDLE Handle,
        EFI_GUID*  Protocol,
        void**     Interface
    );
    void* Reserved;
    void* RegisterProtocolNotify;
    void* LocateHandle;
    void* LocateDevicePath;
    void* InstallConfigurationTable;

    // Image Services (5)
    void* LoadImage;
    void* StartImage;
    void* Exit;
    void* UnloadImage;
    EFI_STATUS (EFIAPI *ExitBootServices)(
        EFI_HANDLE ImageHandle,
        UINTN      MapKey
    );

    // Misc (3)
    void* GetNextMonotonicCount;
    void* Stall;
    void* SetWatchdogTimer;

    // DriverSupport (2)
    void* ConnectController;
    void* DisconnectController;

    // Open/Close Protocol (3)
    void* OpenProtocol;
    void* CloseProtocol;
    void* OpenProtocolInformation;

    // Library (3)
    void* ProtocolsPerHandle;
    void* LocateHandleBuffer;
    EFI_STATUS (EFIAPI *LocateProtocol)(
        EFI_GUID* Protocol,
        void*     Registration,
        void**    Interface
    );
};

// ── Configuration Table ────────────────────────────────────────────────────

struct EFI_CONFIGURATION_TABLE {
    EFI_GUID VendorGuid;
    void*    VendorTable;
};

// ── System Table ───────────────────────────────────────────────────────────

struct EFI_SYSTEM_TABLE {
    char _hdr[24];

    CHAR16*                          FirmwareVendor;
    uint32_t                         FirmwareRevision;
    uint32_t                         _pad;

    EFI_HANDLE                       ConsoleInHandle;
    void*                            ConIn;
    EFI_HANDLE                       ConsoleOutHandle;
    EFI_SIMPLE_TEXT_OUTPUT_PROTOCOL*  ConOut;
    EFI_HANDLE                       StandardErrorHandle;
    void*                            StdErr;
    void*                            RuntimeServices;
    EFI_BOOT_SERVICES*               BootServices;
    UINTN                            NumberOfTableEntries;
    EFI_CONFIGURATION_TABLE*         ConfigurationTable;
};

// ── Utility ────────────────────────────────────────────────────────────────

inline bool guid_equal(const EFI_GUID& a, const EFI_GUID& b) {
    return a.Data1 == b.Data1 && a.Data2 == b.Data2 && a.Data3 == b.Data3 &&
           a.Data4[0] == b.Data4[0] && a.Data4[1] == b.Data4[1] &&
           a.Data4[2] == b.Data4[2] && a.Data4[3] == b.Data4[3] &&
           a.Data4[4] == b.Data4[4] && a.Data4[5] == b.Data4[5] &&
           a.Data4[6] == b.Data4[6] && a.Data4[7] == b.Data4[7];
}