/****************************************************************/
/*								*/
/*			     device.h				*/
/*			Device Driver Header File		*/
/*								*/
/*			 November 20, 1991			*/
/*								*/
/*			Copyright (c) 1995			*/
/*			Pasquale J. Villani			*/
/*			All Rights Reserved			*/
/*								*/
/* This file is part of DOS-C.					*/
/*								*/
/* DOS-C is free software; you can redistribute it and/or	*/
/* modify it under the terms of the GNU General Public License	*/
/* as published by the Free Software Foundation; either version	*/
/* 2, or (at your option) any later version.			*/
/*								*/
/* DOS-C is distributed in the hope that it will be useful, but	*/
/* WITHOUT ANY WARRANTY; without even the implied warranty of	*/
/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See	*/
/* the GNU General Public License for more details.		*/
/*								*/
/* You should have received a copy of the GNU General Public	*/
/* License along with DOS-C; see the file COPYING.  If not,	*/
/* write to the Free Software Foundation, 675 Mass Ave,		*/
/* Cambridge, MA 02139, USA.					*/
/****************************************************************/



/* $Logfile:   C:/dos-c/hdr/device.h_v  $ */
#ifdef MAIN
# ifndef IPL
static BYTE *device_hRcsId = "$Header:   C:/dos-c/hdr/device.h_v   1.2   01 Sep 1995 17:35:40   patv  $";
# endif
#endif

/*
 * $Log:   C:/dos-c/hdr/device.h_v  $
 *	
 *	   Rev 1.2   01 Sep 1995 17:35:40   patv
 *	First GPL release.
 *	
 *	   Rev 1.1   30 Jul 1995 20:43:48   patv
 *	Eliminated version strings in ipl
 *	
 *	   Rev 1.0   02 Jul 1995 10:39:30   patv
 *	Initial revision.
 */

/*
 *	Status Word Bits
 */

#define	S_ERROR		0x8000		/* Error bit			*/
#define	S_BUSY		0x0200		/* Device busy bit		*/
#define	S_DONE		0x0100		/* Device operation completed	*/
#define	S_MASK		0x00ff		/* Mask to extract error code	*/


/*
 *	MEDIA Descriptor Byte Bits
 */

#define	MD_2SIDE	1		/* MEDIA is two sided		*/
#define	MD_8SECTOR	2		/* MEDIA is eight sectored	*/
#define	MD_REMOVABLE	4		/* MEDIA is removable (floppy)	*/


/*
 *	Media Return Codes
 */
#define	M_CHANGED	-1		/* MEDIA was changed		*/
#define	M_DONT_KNOW	0		/* MEDIA state unkown		*/
#define	M_NOT_CHANGED	1		/* MEDIA was not changed	*/



/*
 *	Error Return Codes
 */

#define	E_WRPRT		0		/* Write Protect		*/
#define	E_UNIT		1		/* Unknown Unit			*/
#define	E_NOTRDY	2		/* Device Not Ready		*/
#define	E_CMD		3		/* Unknown Command		*/
#define	E_CRC		4		/* Crc Error			*/
#define	E_LENGTH	5		/* Bad Length			*/
#define	E_SEEK		6		/* Seek Error			*/
#define	E_MEDIA		7		/* Unknown MEDIA		*/
#define	E_NOTFND	8		/* Sector Not Found		*/
#define	E_PAPER		9		/* No Paper			*/
#define	E_WRITE		10		/* Write Fault			*/
#define	E_READ		11		/* Read Fault			*/
#define	E_FAILURE	12		/* General Failure		*/

/*
 *	Command codes
 */

#define	C_INIT		0		/* Initialize			*/
#define	C_MEDIACHK	1		/* MEDIA Check			*/
#define	C_BLDBPB	2		/* Build BPB			*/
#define	C_IOCTLIN	3		/* Ioctl In			*/
#define	C_INPUT		4		/* Input (Read)			*/
#define	C_NDREAD	5		/* Non-destructive Read		*/
#define	C_ISTAT		6		/* Input Status			*/
#define	C_IFLUSH	7		/* Input Flush			*/
#define	C_OUTPUT	8		/* Output (Write)		*/
#define	C_OUTVFY	9		/* Output with verify		*/
#define	C_OSTAT		10		/* Output			*/
#define	C_OFLUSH	11		/* Output Flush			*/
#define	C_IOCTLOUT	12		/* Ioctl Out			*/
#define	C_OPEN		13		/* Device Open			*/
#define	C_CLOSE		14		/* Device Close			*/
#define	C_REMMEDIA	15		/* Removable MEDIA		*/
#define	C_OUB		16		/* Output till busy		*/
#define	C_GENIOCTL	19		/* Generic Ioctl		*/
#define	C_GETLDEV	23		/* Get Logical Device		*/
#define	C_SETLDEV	24		/* Set Logical Device		*/


/*
 *	Convienence macros
 */
#define	failure(x)	(S_ERROR+S_DONE+x)
#ifndef TRUE
#define	TRUE		1
#endif
#ifndef	FALSE
#define	FALSE		0
#endif
#define mk_offset(far_ptr)	((UWORD)(far_ptr))
#define mk_segment(far_ptr) ((UWORD)((ULONG)(far_ptr) >> 16))
#define	far_ptr(seg, off) ((VOID FAR *)(((ULONG)(off))+((ULONG)(seg) << 16)))



/*
 *	structures
 */


/* Device header */

struct dhdr
{
	struct dhdr
		FAR	*dh_next;
	UWORD		dh_attr;
	VOID		(*dh_strategy)();
	VOID		(*dh_interrupt)();
	BYTE		dh_name[8];
};

#define	ATTR_CHAR	0x8000
#define	ATTR_RAW	0x0400


/*									*/
/* Bios Parameter Block structure					*/
/*									*/
/* The following offsets are computed as byte offsets and are based on	*/
/* the struct below. The struct itself cannot be used because on some	*/
/* compilers, structure alignement may be forced, throwing following	*/
/* fields off (e.g. - BYTE, followed by a WORD may have a byte of fill	*/
/* inserted in between; the WORD would then be at offset 2, not 1).	*/
/*									*/
#define BPB_NBYTE	0
#define BPB_NSECTOR	2
#define BPB_NRESERVED	3
#define BPB_NFAT	5
#define BPB_NDIRENT	6
#define BPB_NSIZE	8
#define BPB_MDESC	10
#define BPB_NFSECT	11
#define BPB_NSECS	13
#define BPB_NHEADS	15
#define BPB_HIDDEN	17
#define BPB_HUGE	21
#define BPB_SIZEOF	25

typedef struct
{
	UWORD	bpb_nbyte;		/* Bytes per Sector		*/
	UBYTE	bpb_nsector;		/* Sectors per Allocation Unit	*/
	UWORD	bpb_nreserved;		/* # Reserved Sectors		*/
	UBYTE	bpb_nfat;		/* # FAT's			*/
	UWORD	bpb_ndirent;		/* # Root Directory entries	*/
	UWORD	bpb_nsize;		/* Size in sectors		*/
	UBYTE	bpb_mdesc;		/* MEDIA Descriptor Byte	*/
	UWORD	bpb_nfsect;		/* FAT size in sectors		*/
	UWORD	bpb_nsecs;		/* Sectors per track		*/
	UWORD	bpb_nheads;		/* Number of heads		*/
	ULONG	bpb_hidden;		/* Hidden sectors		*/
	ULONG	bpb_huge;		/* Size in sectors if		*/
					/* bpb_nsize== 0				*/
} bpb;


/*									*/
/* Boot Block (Super Block)						*/
/*									*/
/* See BPB comments for the offsets below				*/
/*									*/
#define BT_JUMP		0
#define BT_OEM		3
#define BT_BPB		11
#define BT_SIZEOF	36

typedef struct
{
	BYTE	bt_jump[3];		/* Boot Jump opcodes		*/
	BYTE	bt_oem[8];		/* OEM Name			*/
	bpb	bt_bpb;			/* BPB for this media/device	*/
	WORD	bt_nsecs;		/* # Sectors per Track		*/
	WORD	bt_nheads;		/* # Heads			*/
	WORD	bt_hidden;		/* # Hidden sectors		*/
	LONG	bt_huge;		/* use if nsecs == 0		*/
} boot;

typedef	boot	super;		/* Alias for boot structure		*/

typedef struct
{
	BYTE	r_length;	/*  Request Header length		*/
	BYTE	r_unit;		/*  Unit Code				*/
	BYTE	r_command;	/*  Command Code			*/
	WORD	r_status;	/*  Status				*/
	BYTE	r_reserved[8];	/*  DOS Reserved Area			*/
	union
	{
		struct
		{
			BYTE	_r_nunits;	/*  number of units	*/
			BYTE FAR
				*_r_endaddr;	/*  Ending Address	*/
			bpb			/*  ptr to BPB array	*/
				* FAR *_r_bpbptr;
		} _r_init;
		struct
		{
			BYTE	_r_meddesc;	/*  MEDIA Descriptor	*/
			BYTE	_r_retcode;	/*  Return Code		*/
			BYTE FAR
				*_r_vid;	/* volume id */
		} _r_media;
		struct
		{
			BYTE	_r_meddesc;	/*  MEDIA Descriptor	*/
			boot FAR
				*_r_fat;	/*  boot sector pointer	*/
			bpb FAR
				*_r_bpbpt;	/*  ptr to BPB table	*/
		} _r_bpb;
		struct
		{
			BYTE	_r_meddesc;	/*  MEDIA Descriptor	*/
			BYTE FAR
				*_r_trans;	/*  Transfer Address	*/
			UWORD	_r_count;	/*  Byte/Sector Count	*/
			UWORD	_r_start;	/*  Starting Sector No.	*/
			BYTE FAR
				*_r_vid;	/* Pointer to volume id	*/
                        LONG	_r_huge;	/* for > 32Mb drives	*/
		} _r_rw;
		struct
		{
			BYTE	_r_ndbyte;	/*  Byte Read From Device	*/
		} _r_nd;
	} _r_x;
} request;

#define HUGECOUNT	0xffff
#define MAXSHORT	0xffffl

/*
 * Macros to assist request structure legibility
 */

/* Init packet macros							*/
#define	r_nunits	_r_x._r_init._r_nunits
#define r_endaddr	_r_x._r_init._r_endaddr
#define r_bpbptr	_r_x._r_init._r_bpbptr

/* MEDIA Check packet macros						*/
#define	r_mcmdesc	_r_x._r_media._r_meddesc
#define	r_mcretcode	_r_x._r_media._r_retcode
#define	r_mcvid		_r_x._r_media._r_vid

/* Build BPB packet macros						*/
#define	r_bpmdesc	_r_x._r_bpb._r_meddesc
#define	r_bpfat		_r_x._r_bpb._r_fat
#define	r_bpptr		_r_x._r_bpb._r_bpbpt

/* rw packet macros							*/
#define	r_meddesc	_r_x._r_rw._r_meddesc
#define	r_trans		_r_x._r_rw._r_trans
#define	r_count		_r_x._r_rw._r_count
#define	r_start		_r_x._r_rw._r_start
#define	r_rwvid		_r_x._r_rw._r_vid
#define	r_huge		_r_x._r_rw._r_huge

/* ndread packet macros							*/
#define	r_ndbyte	_r_x._r_nd._r_ndbyte


/* 
 *interrupt support (spl & splx) support - IBM style
 */

#define	I_NONE		0		/* Initial value		*/

/* predefined interrupt levels - 8259 support				*/
#define	IRQ0		0x01		/* Level 0 - highest		*/
#define	IRQ1		0x02
#define	IRQ2		0x04
#define	IRQ3		0x08
#define	IRQ4		0x10
#define	IRQ5		0x20
#define	IRQ6		0x40
#define	IRQ7		0x80		/* Level 7 - lowest		*/

/* standard hardware configuration					*/
#define	I_RTC		IRQ0		/* Timer			*/
#define	I_KBD		IRQ1		/* Keyboard			*/
#define	I_COM2		IRQ3		/* COM1:			*/
#define	I_COM1		IRQ4		/* COM2:			*/
#define	I_HDC		IRQ5		/* Fixed disk			*/
#define	I_FDC		IRQ6		/* Diskette			*/
#define	I_PRT		IRQ7		/* Printer			*/

/* standard hardware vectors - 8259 defined				*/
#define	V_RTC		0x08		/* Timer			*/
#define	V_KBD		0x09		/* Keyboard			*/
#define	V_LEV2		0x0a		/* Level 2 - uncomitted		*/
#define	V_COM2		0x0b		/* COM1:			*/
#define	V_COM1		0x0c		/* COM2:			*/
#define	V_HDC		0x0d		/* Fixed disk			*/
#define	V_FDC		0x0e		/* Diskette			*/
#define	V_PRT		0x0f		/* Printer			*/

#define	V_LEV0		0x08		/* Level 0 - highest		*/
#define	V_LEV1		0x09
#define	V_LEV2		0x0a		/* Level 2 - uncomitted		*/
#define	V_LEV3		0x0b
#define	V_LEV4		0x0c
#define	V_LEV5		0x0d
#define	V_LEV6		0x0e
#define	V_LEV7		0x0f		/* Level 7 - lowest		*/

/*
 */
typedef request FAR *rqptr;
typedef bpb FAR *bpbptr;
typedef	BYTE FAR *byteptr;
typedef struct dhdr FAR *dhdrptr;

/*
 *	externals
 */


extern BYTE FAR *device_end();

/*
 *	end of device.h
 */