/* *  Intel 82077AA Floppy disc device driver */#include	"u.h"#include	"../port/lib.h"#include	"mem.h"#include	"dat.h"#include	"fns.h"#include	"../port/error.h"#include	"io.h" #include	"devtab.h" #define min(a, b)	(a < b ? a : b) /* Registers on the 82077 */ typedef struct Controller Controller;struct Controller{	uchar		sra;		/* (R/O) status register A */			uchar		srb;		/* (R/O) status register B */	uchar		dor;		/* (R/W) digital output register */	uchar		rsvd3;		/* reserved */	uchar		msr;		/* (R/O) main status register */#define dsr	msr	uchar		fifo;		/* (R/W) data FIFO */	uchar		rsvd6;		/* reserved */	uchar		dir;		/* (R/O) digital input register */	uchar		flpctl;		/* (W/O) control (not in 82077) */}; enum			/* Useful numbers */{	Eject_disc	= 0x80,		/* Eject the floppy */	Sel_82077	= 0x40,		/* Scsi/82077 select */	Drv_id		= 0x04,		/* Drive present flag */	Mid1		= 0x02,		/* Media id bits */	Mid2		= 0x01,	Maxdrive	= 4,	Ok		= 0,	Error		= -1,	S512		= 512,}; enum			/* Command set */{	Recal	= 0x07,		Seek	= 0x0F,		Readdat	= 0x06,	Writedat= 0x05,	Sis	= 0x80,}; enum			/* Main status register */{	Drv0_bsy= 0x01,	Drv1_bsy= 0x02,	Drv2_bsy= 0x04,	Drv3_bsy= 0x08,	Cmd_bsy = 0x10,	Non_bsy = 0x20,	Dio	= 0x40,	Rqm	= 0x80,}; enum			/* Dor register bits */{	Moten3	= 0x80,	Moten2	= 0x40,	Moten1	= 0x20,	Moten0	= 0x10,	Dmagate = 0x08,	Reset	= 0x04,	Drvsel1	= 0x02,	Drvsel0 = 0x01,}; /* *  floppy types */typedef struct Type Type;struct Type{	char	*name;	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 */	}; Type floppytype[] ={	"MF2HD",	S512,	18,	2,	1,	80,	0x1B,	0x54,	"MF2DD",	S512,	9,	2,	1,	80,	0x1B,	0x54,	"F2HD",		S512,	15,	2,	1,	80,	0x2A,	0x50,	"F2DD",		S512,	8,	2,	1,	40,	0x2A,	0x50,	"F1DD",		S512,	8,	1,	1,	40,	0x2A,	0x50,}; typedef struct Drive Drive;struct Drive{	Type	*t;	uchar	dor;		/* Digital output register (Drive select/Motor on) */	int	synced;		/* Drive is synced with computer */	int	tcyl;		/* Current cylinder */	int	tsec;		/* Current sector */	char	thead;		/* Current head */	Rendez	r;		/* Place to wait for interrupts */	QLock	use;		/* Exclusive use lock */	char	ist;		/* Interrupt status register */	char	pcn;		/* Physical cylinder from Sis command */	char	gotint;	uchar	cmd[32];	/* Command and return status */	int	cmdlen;}; Drive fl[Maxdrive]; static int secbytes[] ={	128,	256,	512,	1024}; struct FLOPdma{	ulong	csr;	uchar	pad1[0x4010-0x14];	ulong	base;	ulong	limit;	ulong	chainbase;	ulong	chainlimit;};	 void 	Xdelay(int);int	issue(Drive*);int	recalibrate(Drive*);int	gotfdintr(void*);void	waitforint(Drive *); enum{	ffddirqid,	ffddataqid,	ffdctlqid,}; Dirtab ffdtab[]={	"data",		{ffddataqid},		0,	0666,	"ctl",		{ffdctlqid},		0,	0666,}; #define Nffdtab (sizeof(ffdtab)/sizeof(Dirtab)) voidffdreset(void){	Controller *fdc = (Controller*)(FDCTLRL); 	print("ffdreset\n");	fdc->flpctl = Sel_82077;	print("fd: (sra=%lux srb=%lux msr=%lux)\n", fdc->sra, fdc->srb, fdc->msr);	fdc->dsr = 0x80;	print("fd: (sra=%lux srb=%lux msr=%lux)\n", fdc->sra, fdc->srb, fdc->msr); 	fl[0].dor = Moten0|Dmagate|Reset;} voidffdinit(void){} Chan *ffdattach(char *spec){	return devattach('f', spec);} Chan *ffdclone(Chan *c, Chan *nc){	return devclone(c, nc);} intffdwalk(Chan *c, char *name){	return devwalk(c, name, ffdtab, (long)Nffdtab, devgen);} voidffdstat(Chan *c, char *db){	devstat(c, db, ffdtab, (long)Nffdtab, devgen);} Chan *ffdopen(Chan *c, int omode){	if(c->qid.path == CHDIR){		if(omode != OREAD)			error(Eperm);	} 	if(fl[0].synced == 0)		recalibrate(fl); 	c->mode = openmode(omode);	c->flag |= COPEN;	c->offset = 0;	return c;} voidffdcreate(Chan *c, char *name, int omode, ulong perm){	error(Eperm);} voidffdremove(Chan *c){	error(Eperm);} voidffdwstat(Chan *c, char *dp){	error(Eperm);} voidffdclose(Chan *c){} longffdread(Chan *c, void *a, long n, ulong offset){ 	switch((int)(c->qid.path&~CHDIR)){	case ffddirqid:		return devdirread(c, a, n, ffdtab, Nffdtab, devgen);	case ffddataqid:		break;	case ffdctlqid:		return n;	default:		n=0;		break;	}	return n;} longffdwrite(Chan *c, char *a, long n, ulong offset){	Controller *fdc = (Controller*)(FDCTLRL);	char buf[32];	int i; 	switch((int)(c->qid.path&~CHDIR)){	case ffddataqid:		break;	case ffdctlqid:		strncpy(buf, a, min(sizeof(buf), n));		if(strncmp(buf, "eject", 5) == 0) {			fdc->dor = 0x1c;			fdc->flpctl = Sel_82077;			Xdelay(100);			fdc->flpctl = Eject_disc|Sel_82077;			Xdelay(100);			fdc->flpctl = Sel_82077;		}		else			error(Ebadarg);	default:		error(Ebadusefd);	}	return n;} intrecalibrate(Drive *dp){			dp->cmd[0] = Recal;	dp->cmd[1] = dp - fl;	dp->cmdlen = 2; 	if(issue(dp) != Ok)		return Error; 	waitforint(dp);	dp->synced = 1;			/* Drive in sync with controller */} voidwaitforint(Drive *dp){	Controller *fdc = (Controller*)(FDCTLRL);		tsleep(&dp->r, gotfdintr, dp, 2000);	if(dp->gotint == 0) {		print("fd%d: operation timed out (sra=%lux srb=%lux msr=%lux)\n",						dp-fl, fdc->sra, fdc->srb, fdc->msr);	}	dp->gotint = 0;} intissue(Drive *dp){	Controller *fdc = (Controller*)(FDCTLRL);	uchar *cdb = dp->cmd;	int i; 	print("fd: (msr=%lux)\n", fdc->msr); 	for(i = 0; i < 1000; i++) {		if((fdc->msr&(Cmd_bsy|Rqm|Dio)) != Rqm)			continue; 		fdc->dor = dp->dor;			/* Motor on and select */ 		for(i = 0; i < dp->cmdlen; i++) {	/* Load command fifo */			while((fdc->msr&Rqm) == 0)				;			if(i == 1 && (fdc->msr&(Dio|Cmd_bsy) == (Dio|Cmd_bsy)))				print("fd: illegal cmd %lux (msr=%lux)\n", cdb[-1], fdc->msr);			fdc->fifo = *cdb++;		} 		return Ok;	}	print("fd: controller cmd timed out (msr=%lux)\n", fdc->msr);	return Error;} voidblock2phys(Drive *dp, ulong off){	int lsec; 	lsec = off/secbytes[dp->t->bytes];	dp->tcyl = lsec/(dp->t->sectors*dp->t->heads);	dp->tsec = (lsec % dp->t->sectors) + 1;	dp->thead = (lsec/dp->t->sectors) % dp->t->heads;} intgotfdintr(void *dp){	return ((Drive*)dp)->gotint;} voidfloppyintr(void){	Controller *fdc = (Controller*)(FDCTLRL);	Drive *dp = &fl[fdc->dor&3]; 	print("floppy intr %d\n", dp-fl); 	dp->cmd[0] = Sis;	dp->cmdlen = 1;	if(issue(dp) != Ok)		print("fd%d: Sis issue failed\n", dp-fl); 	dp->ist = fdc->fifo;	dp->pcn = fdc->fifo; 	print("ist %lux %lux\n", dp->ist, dp->pcn);	if(u) {		fl[0].gotint = 1;		wakeup(&fl[0].r);	}}