typedef	struct FController FController;typedef	struct FDrive FDrive;typedef struct FType FType; static void floppyintr(Ureg*);static int floppyon(FDrive*);static void floppyoff(FDrive*);static void floppysetdef(FDrive*); /* *  a floppy drive */struct FDrive{	FType	*t;		/* floppy type */	int	dt;		/* drive type */	int	dev; 	ulong	lasttouched;	/* time last touched */	int	cyl;		/* current arm position */	int	confused;	/* needs to be recalibrated */	int	offset;		/* current offset */	int	vers;	int	maxtries; 	int	tcyl;		/* target cylinder */	int	thead;		/* target head */	int	tsec;		/* target sector */	long	len;		/* size of xfer */ 	uchar	*cache;		/* track cache */	int	ccyl;	int	chead; //	Rendez	r;		/* waiting here for motor to spin up */	void	*aux;}; /* *  controller for 4 floppys */struct FController{//	QLock;			/* exclusive access to the contoller */ 	int	ndrive;	FDrive	*d;		/* the floppy drives */	FDrive	*selected;	int	rate;		/* current rate selected */	uchar	cmd[14];	/* command */	int	ncmd;		/* # command bytes */	uchar	stat[14];	/* command status */	int	nstat;		/* # status bytes */	int	confused;	/* controler needs to be reset *///	Rendez	r;		/* wait here for command termination */	int	motor;		/* bit mask of spinning disks *///	Rendez	kr;		/* for motor watcher */}; /* *  floppy types (all MFM encoding) */struct FType{	char	*name;	int	dt;		/* compatible drive type */	int	bytes;		/* bytes/sector */	int	sectors;	/* sectors/track */	int	heads;		/* number of heads */	int	steps;		/* steps per cylinder */	int	tracks;		/* tracks/disk */	int	gpl;		/* intersector gap length for read/write */		int	fgpl;		/* intersector gap length for format */	int	rate;		/* rate code */ 	/*	 *  these depend on previous entries and are set filled in	 *  by floppyinit	 */	int	bcode;		/* coded version of bytes for the controller */	long	cap;		/* drive capacity in bytes */	long	tsize;		/* track size in bytes */};/* bits in the registers */enum{	/* status registers a & b */	Psra=		0x3f0,	Psrb=		0x3f1, 	/* digital output register */	Pdor=		0x3f2,	Fintena=	0x8,	/* enable floppy interrupt */	Fena=		0x4,	/* 0 == reset controller */ 	/* main status register */	Pmsr=		0x3f4,	Fready=		0x80,	/* ready to be touched */	Ffrom=		0x40,	/* data from controller */	Ffloppybusy=	0x10,	/* operation not over */ 	/* data register */	Pfdata=		0x3f5,	Frecal=		0x07,	/* recalibrate cmd */	Fseek=		0x0f,	/* seek cmd */	Fsense=		0x08,	/* sense cmd */	Fread=		0x66,	/* read cmd */	Freadid=	0x4a,	/* read track id */	Fspec=		0x03,	/* set hold times */	Fwrite=		0x45,	/* write cmd */	Fformat=	0x4d,	/* format cmd */	Fmulti=		0x80,	/* or'd with Fread or Fwrite for multi-head */	Fdumpreg=	0x0e,	/* dump internal registers */ 	/* digital input register */	Pdir=		0x3F7,	/* disk changed port (read only) */	Pdsr=		0x3F7,	/* data rate select port (write only) */	Fchange=	0x80,	/* disk has changed */ 	/* status 0 byte */	Drivemask=	3<<0,	Seekend=	1<<5,	Codemask=	(3<<6)|(3<<3),	Cmdexec=	1<<6, 	/* status 1 byte */	Overrun=	0x10,}; /* *  types of drive (from PC equipment byte) */enum{	Tnone=		0,	T360kb=		1,	T1200kb=	2,	T720kb=		3,	T1440kb=	4,}; static voidpcfloppyintr(Ureg *ur, void *a){	USED(a); 	floppyintr(ur);} voidfloppysetup0(FController *fl){	uchar equip; 	/*	 * Read nvram for types of floppies 0 & 1.	 * Always try floppy 0.	 */	equip = nvramread(0x10);	fl->ndrive = 1; 	if(equip & 0xf)		fl->ndrive++; 	/*	 * Allocate the drive storage.	 * There's always one.  defend against	 * cruddy intel bios.	 */	fl->d = xalloc(fl->ndrive*sizeof(FDrive));	fl->d[0].dt = (equip >> 4) & 0xf;	if(fl->d[0].dt == Tnone || fl->d[0].dt > T1440kb){		if(fl->d[0].dt > T1440kb)			print("unknown fl0 type %d; assume el torrito\n", fl->d[0].dt);		fl->d[0].dt = T1440kb;	} 	if(fl->ndrive == 2){		fl->d[1].dt = equip & 0xf;		if(fl->d[0].dt > T1440kb){			fl->d[0].dt = Tnone;			fl->ndrive--;		}	}} voidfloppysetup1(FController*){//	intrenable(VectorFLOPPY, pcfloppyintr, fl, BUSUNKNOWN);	setvec(VectorFLOPPY, pcfloppyintr, 0);}  static vlong pcfloppyseek(FDrive*, vlong);FController	fl; vlongfloppyseek(Fs *fs, vlong off){	FDrive *dp; 	dp = &fl.d[fs->dev];	return pcfloppyseek(dp, off);}