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#ifndef _BZIMAGE_H
#define _BZIMAGE_H
FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
#include <stdint.h>
/**
* A bzImage header
*
* As documented in Documentation/i386/boot.txt
*/
struct bzimage_header {
/** The size of the setup in sectors
*
* If this field contains 0, assume it contains 4.
*/
uint8_t setup_sects;
/** If set, the root is mounted readonly */
uint16_t root_flags;
/** DO NOT USE - for bootsect.S use only */
uint16_t syssize;
/** DO NOT USE - obsolete */
uint16_t swap_dev;
/** DO NOT USE - for bootsect.S use only */
uint16_t ram_size;
/** Video mode control */
uint16_t vid_mode;
/** Default root device number */
uint16_t root_dev;
/** 0xAA55 magic number */
uint16_t boot_flag;
/** Jump instruction */
uint16_t jump;
/** Magic signature "HdrS" */
uint32_t header;
/** Boot protocol version supported */
uint16_t version;
/** Boot loader hook (see below) */
uint32_t realmode_swtch;
/** The load-low segment (0x1000) (obsolete) */
uint16_t start_sys;
/** Pointer to kernel version string */
uint16_t kernel_version;
/** Boot loader identifier */
uint8_t type_of_loader;
/** Boot protocol option flags */
uint8_t loadflags;
/** Move to high memory size (used with hooks) */
uint16_t setup_move_size;
/** Boot loader hook (see below) */
uint32_t code32_start;
/** initrd load address (set by boot loader) */
uint32_t ramdisk_image;
/** initrd size (set by boot loader) */
uint32_t ramdisk_size;
/** DO NOT USE - for bootsect.S use only */
uint32_t bootsect_kludge;
/** Free memory after setup end */
uint16_t heap_end_ptr;
/** Unused */
uint16_t pad1;
/** 32-bit pointer to the kernel command line */
uint32_t cmd_line_ptr;
/** Highest legal initrd address */
uint32_t initrd_addr_max;
/** Physical addr alignment required for kernel */
uint32_t kernel_alignment;
/** Whether kernel is relocatable or not */
uint8_t relocatable_kernel;
/** Unused */
uint8_t pad2[3];
/** Maximum size of the kernel command line */
uint32_t cmdline_size;
} __attribute__ (( packed ));
/** Offset of bzImage header within kernel image */
#define BZI_HDR_OFFSET 0x1f1
/** bzImage boot flag value */
#define BZI_BOOT_FLAG 0xaa55
/** bzImage magic signature value */
#define BZI_SIGNATURE 0x53726448
/** bzImage boot loader identifier for Etherboot */
#define BZI_LOADER_TYPE_ETHERBOOT 0x40
/** bzImage boot loader identifier for iPXE
*
* We advertise ourselves as Etherboot version 6.
*/
#define BZI_LOADER_TYPE_IPXE ( BZI_LOADER_TYPE_ETHERBOOT | 0x06 )
/** bzImage "load high" flag */
#define BZI_LOAD_HIGH 0x01
/** Load address for high-loaded kernels */
#define BZI_LOAD_HIGH_ADDR 0x100000
/** Load address for low-loaded kernels */
#define BZI_LOAD_LOW_ADDR 0x10000
/** bzImage "kernel can use heap" flag */
#define BZI_CAN_USE_HEAP 0x80
/** bzImage special video mode "normal" */
#define BZI_VID_MODE_NORMAL 0xffff
/** bzImage special video mode "ext" */
#define BZI_VID_MODE_EXT 0xfffe
/** bzImage special video mode "ask" */
#define BZI_VID_MODE_ASK 0xfffd
/** bzImage maximum initrd address for versions < 2.03 */
#define BZI_INITRD_MAX 0x37ffffff
/** bzImage command-line structure used by older kernels */
struct bzimage_cmdline {
/** Magic signature */
uint16_t magic;
/** Offset to command line */
uint16_t offset;
} __attribute__ (( packed ));
/** Offset of bzImage command-line structure within kernel image */
#define BZI_CMDLINE_OFFSET 0x20
/** bzImage command line present magic marker value */
#define BZI_CMDLINE_MAGIC 0xa33f
/** Assumed size of real-mode portion (including .bss) */
#define BZI_ASSUMED_RM_SIZE 0x8000
/** Amount of stack space to provide */
#define BZI_STACK_SIZE 0x1000
/** Maximum size of command line */
#define BZI_CMDLINE_SIZE 0x7ff
#endif /* _BZIMAGE_H */