linuxboot.h

#ifndef LINUXBOOT_H
#define LINUXBOOT_H 1

/* xloadflags */
#define XLF_KERNEL_64			(1<<0)
#define XLF_CAN_BE_LOADED_ABOVE_4G	(1<<1)
#define XLF_EFI_HANDOVER_32		(1<<2)
#define XLF_EFI_HANDOVER_64		(1<<3)
#define XLF_EFI_KEXEC			(1<<4)
#define XLF_5LEVEL			(1<<5)
#define XLF_5LEVEL_ENABLED		(1<<6)

struct setup_header {
	uint8_t	setup_sects;
	uint16_t	root_flags;
	uint32_t	syssize;
	uint16_t	ram_size;
	uint16_t	vid_mode;
	uint16_t	root_dev;
	uint16_t	boot_flag;
	uint16_t	jump;
	uint32_t	header;
	uint16_t	version;
	uint32_t	realmode_swtch;
	uint16_t	start_sys_seg;
	uint16_t	kernel_version;
	uint8_t	type_of_loader;
	uint8_t	loadflags;
	uint16_t	setup_move_size;
	uint32_t	code32_start;
	uint32_t	ramdisk_image;
	uint32_t	ramdisk_size;
	uint32_t	bootsect_kludge;
	uint16_t	heap_end_ptr;
	uint8_t	ext_loader_ver;
	uint8_t	ext_loader_type;
	uint32_t	cmd_line_ptr;
	uint32_t	initrd_addr_max;
	uint32_t	kernel_alignment;
	uint8_t	relocatable_kernel;
	uint8_t	min_alignment;
	uint16_t	xloadflags;
	uint32_t	cmdline_size;
	uint32_t	hardware_subarch;
	uint64_t	hardware_subarch_data;
	uint32_t	payload_offset;
	uint32_t	payload_length;
	uint64_t	setup_data;
	uint64_t	pref_address;
	uint32_t	init_size;
	uint32_t	handover_offset;
	uint32_t	kernel_info_offset;
} __attribute__((packed));

struct efi_info {
	uint32_t efi_loader_signature;
	uint32_t efi_systab;
	uint32_t efi_memdesc_size;
	uint32_t efi_memdesc_version;
	uint32_t efi_memmap;
	uint32_t efi_memmap_size;
	uint32_t efi_systab_hi;
	uint32_t efi_memmap_hi;
};

/*
 * This is the maximum number of entries in struct boot_params::e820_table
 * (the zeropage), which is part of the x86 boot protocol ABI:
 */
#define E820_MAX_ENTRIES_ZEROPAGE 128

/*
 * The E820 memory region entry of the boot protocol ABI:
 */
struct boot_e820_entry {
	uint64_t addr;
	uint64_t size;
	uint32_t type;
} __attribute__((packed));

/* The so-called "zeropage" */
struct boot_params {
	uint8_t screen_info[0x40];			/* 0x000 */
	uint8_t apm_bios_info[0x14];		/* 0x040 */
	uint8_t  _pad2[4];					/* 0x054 */
	uint64_t  tboot_addr;				/* 0x058 */
	uint8_t ist_info[0x10];			/* 0x060 */
	uint64_t acpi_rsdp_addr;				/* 0x070 */
	uint8_t  _pad3[8];					/* 0x078 */
	uint8_t  hd0_info[16];	/* obsolete! */		/* 0x080 */
	uint8_t  hd1_info[16];	/* obsolete! */		/* 0x090 */
	uint8_t sys_desc_table[0x10]; /* obsolete! */	/* 0x0a0 */
	uint8_t olpc_ofw_header[0x10];		/* 0x0b0 */
	uint32_t ext_ramdisk_image;			/* 0x0c0 */
	uint32_t ext_ramdisk_size;				/* 0x0c4 */
	uint32_t ext_cmd_line_ptr;				/* 0x0c8 */
	uint8_t  _pad4[116];				/* 0x0cc */
	uint8_t edid_info[0x80];			/* 0x140 */
	struct efi_info efi_info;			/* 0x1c0 */
	uint32_t alt_mem_k;				/* 0x1e0 */
	uint32_t scratch;		/* Scratch field! */	/* 0x1e4 */
	uint8_t  e820_entries;				/* 0x1e8 */
	uint8_t  eddbuf_entries;				/* 0x1e9 */
	uint8_t  edd_mbr_sig_buf_entries;			/* 0x1ea */
	uint8_t  kbd_status;				/* 0x1eb */
	uint8_t  secure_boot;				/* 0x1ec */
	uint8_t  _pad5[2];					/* 0x1ed */
	/*
	 * The sentinel is set to a nonzero value (0xff) in header.S.
	 *
	 * A bootloader is supposed to only take setup_header and put
	 * it into a clean boot_params buffer. If it turns out that
	 * it is clumsy or too generous with the buffer, it most
	 * probably will pick up the sentinel variable too. The fact
	 * that this variable then is still 0xff will let kernel
	 * know that some variables in boot_params are invalid and
	 * kernel should zero out certain portions of boot_params.
	 */
	uint8_t  sentinel;					/* 0x1ef */
	uint8_t  _pad6[1];					/* 0x1f0 */
	struct setup_header hdr;    /* setup header */	/* 0x1f1 */
	uint8_t  _pad7[0x290-0x1f1-sizeof(struct setup_header)];
	uint32_t edd_mbr_sig_buffer[16];	/* 0x290 */
	struct boot_e820_entry e820_table[E820_MAX_ENTRIES_ZEROPAGE]; /* 0x2d0 */
	uint8_t  _pad8[48];				/* 0xcd0 */
	uint8_t eddbuf[0x1ec];		/* 0xd00 */
	uint8_t  _pad9[276];				/* 0xeec */
} __attribute__((packed));

#endif