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#ifndef __LINUXMT_BOOT_H
#define __LINUXMT_BOOT_H

/* This header file contains the definitions that relate to the ELKS
 * boot variables, ready for use by any file needing access to them.
 */

/* Root flags */
#define RF_NONE         0
#define RF_RO           1

#define ROOTFLAGS       RF_NONE

/* ELKS flags */
#define EF_NONE         0
#define EF_AS_BLOB      0x01            /* says that setup and kernel are
                                           loaded as one blob at SETUPSEG:0,
                                           and setup may need to move kernel
                                           to SYSSEG:0 */
#define EF_BIOS_DEV_NUM 0x02            /* says that root_dev does not give
                                           a <major, minor> block device
                                           number, but only a BIOS drive
                                           number (and possibly other
                                           information); setup or kernel
                                           should use this drive number to
                                           figure out the correct root
                                           device */

/* If we are not building the (dummy) boot sector (elks/elks/arch/i86/boot/
   {bootsect.S, netbootsect.S}) at the start of /linux, then define
   constants giving the offsets of various fields within /linux.

   The "dummy" boot sector is no longer built or executed. Instead, the values
   below correspond to offsets in the 512-byte setup.S data segment, known as INITSEG.
   These values are initialized then shared with Linux kernel at startup through the
   same segment. The tools/build utility writes a 512-byte sector of zeros
   prepended to the setup and kernel images, with the elks_magic, setup_sects,
   and syssize fields filled in, which are then either checked by the real
   boot sector (elks_magic) or shared with setup.S for relocating the kernel
   (setup_sects and syssize) at boot.

   The fields in /linux are mainly based on an old version of the Linux/x86
   Boot Protocol (https://www.kernel.org/doc/html/latest/x86/boot.html).
   Fields which are specific to ELKS are indicated below.  */

#ifndef DUMMYBOOT
#define screen_cols     7               /* byte screen width*/
#define screen_lines    14              /* byte screen height*/
#define cpu_type        0x20            /* byte cpu type*/
#define mem_kbytes      0x2a            /* word base memory size in Kbytes*/
#define proc_name       0x30            /* 16 bytes processor name string*/
#define cpu_id          0x50            /* 13 bytes cpu id string*/
#define part_offset     0x1e2           /* long sector offset of booted partition*/
#define elks_magic      0x1e6           /* long "ELKS" (45 4c 4b 53) checked by boot sector*/
#define xms_kbytes      0x1ea           /* word size of XMS memory in Kbytes*/
#define hma_kernel      0x1ec           /* byte hma=kernel seen in /bootopts*/
#define setup_sects     0x1f1           /* byte 512-byte sectors used by setup.S*/
#define syssize         0x1f4           /* word paragraph kernel size used by setup.S*/
#define elks_flags      0x1f6           /* byte ELKS flags, BLOB and BIOS_DRV*/
#define root_dev        0x1fc           /* word BIOS drive or kdev_t ROOT_DEV*/
#define boot_flag       0x1fe           /* word constant AA55h checked by boot sector*/
#endif

#endif
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