/*-
 * Copyright (c) 2012 Andriy Gapon <avg@FreeBSD.org>
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms are freely
 * permitted provided that the above copyright notice and this
 * paragraph and the following disclaimer are duplicated in all
 * such forms.
 *
 * This software is provided "AS IS" and without any express or
 * implied warranties, including, without limitation, the implied
 * warranties of merchantability and fitness for a particular
 * purpose.
 *
 * $FreeBSD$
 */

#ifndef _BOOT_I386_ARGS_H_
#define	_BOOT_I386_ARGS_H_

#define	KARGS_FLAGS_CD		0x1
#define	KARGS_FLAGS_PXE		0x2
#define	KARGS_FLAGS_ZFS		0x4
#define	KARGS_FLAGS_EXTARG	0x8	/* variably sized extended argument */

#define	BOOTARGS_SIZE	24	/* sizeof(struct bootargs) */
#define	BA_BOOTFLAGS	8	/* offsetof(struct bootargs, bootflags) */
#define	BA_BOOTINFO	20	/* offsetof(struct bootargs, bootinfo) */
#define	BI_SIZE		48	/* offsetof(struct bootinfo, bi_size) */

/*
 * We reserve some space above BTX allocated stack for the arguments
 * and certain data that could hang off them.  Currently only struct bootinfo
 * is supported in that category.  The bootinfo is placed at the top
 * of the arguments area and the actual arguments are placed at ARGOFF offset
 * from the top and grow towards the top.  Hopefully we have enough space
 * for bootinfo and the arguments to not run into each other.
 * Arguments area below ARGOFF is reserved for future use.
 */
#define	ARGSPACE	0x1000	/* total size of the BTX args area */
#define	ARGOFF		0x800	/* actual args offset within the args area */
#define	ARGADJ		(ARGSPACE - ARGOFF)

#ifndef __ASSEMBLER__

struct bootargs
{
	uint32_t			howto;
	uint32_t			bootdev;
	uint32_t			bootflags;
	union {
		struct {
			uint32_t	pxeinfo;
			uint32_t	reserved;
		};
		uint64_t		zfspool;
	};
	uint32_t			bootinfo;

	/*
	 * If KARGS_FLAGS_EXTARG is set in bootflags, then the above fields
	 * are followed by a uint32_t field that specifies a size of the
	 * extended arguments (including the size field).
	 */
};

#endif /*__ASSEMBLER__*/

#endif	/* !_BOOT_I386_ARGS_H_ */