fd.c

早期freebsd实现

/*-
 * Copyright (c) 1990, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Don Ahn.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 *	@(#)fd.c	8.1 (Berkeley) 6/11/93
 */

#include "fd.h"
#if NFD > 0
/*
 * This driver assumed that NFD == 2. Now it works for NFD == 1 or NFD == 2
 * It will probably not work for NFD > 2.
 */
#include <sys/param.h>
#include <sys/dkbad.h>
#include <sys/systm.h>
#include <sys/conf.h>
#include <sys/file.h>
#include <sys/ioctl.h>
#include <sys/buf.h>
#include <sys/uio.h>

#include <i386/isa/isa_device.h>
#include <i386/isa/fdreg.h>
#include <i386/isa/icu.h>

#define	FDUNIT(s)	((s)&1)
#define	FDTYPE(s)	(((s)>>1)&7)
#define FDMOTOR(u) 	(fd_unit[(u)].motor ? (1 << (4 + (u))) : 0)

#define b_cylin b_resid
#define b_step b_resid
#define FDBLK 512
#define NUMTYPES 4

struct fd_type {
	int	sectrac;		/* sectors per track         */
	int	secsize;		/* size code for sectors     */
	int	datalen;		/* data len when secsize = 0 */
	int	gap;			/* gap len between sectors   */
	int	tracks;			/* total num of tracks       */
	int	size;			/* size of disk in sectors   */
	int	steptrac;		/* steps per cylinder        */
	int	trans;			/* transfer speed code       */
};

struct fd_type fd_types[NUMTYPES] = {
 	{ 18,2,0xFF,0x1B,80,2880,1,0 },	/* 1.44 meg HD 3.5in floppy    */
	{ 15,2,0xFF,0x1B,80,2400,1,0 },	/* 1.2 meg HD floppy           */
	{ 9,2,0xFF,0x23,40,720,2,1 },	/* 360k floppy in 1.2meg drive */
	{ 9,2,0xFF,0x2A,40,720,1,1 },	/* 360k floppy in DD drive     */
};

struct fd_u {
	int type;		/* Drive type (HD, DD     */
	int active;		/* Drive activity boolean */
	int motor;		/* Motor on flag          */
	struct buf head;	/* Head of buf chain      */
	struct buf rhead;	/* Raw head of buf chain  */
	int reset;
} fd_unit[NFD];


extern int hz;

/* state needed for current transfer */
static fdc;	/* floppy disk controller io base register */
int	fd_dmachan = 2;
static int fd_skip;
static int fd_state;
static int fd_retry;
static int fd_drive;
static int fd_track = -1;
static int fd_status[7];

/*
	make sure bounce buffer for DMA is aligned since the DMA chip
	doesn't roll over properly over a 64k boundary
*/
extern struct buf *dma_bounce[];

/****************************************************************************/
/*                      autoconfiguration stuff                             */
/****************************************************************************/
int fdprobe(), fdattach(), fd_turnoff();

struct	isa_driver fddriver = {
	fdprobe, fdattach, "fd",
};

fdprobe(dev)
struct isa_device *dev;
{
	return 1;
}

fdattach(dev)
struct isa_device *dev;
{	int	s;

	fdc = dev->id_iobase;
	/* Set transfer to 500kbps */
	outb(fdc+fdctl,0);
	fd_turnoff(0);
}

int
Fdsize(dev)
dev_t	dev;
{
	return(2400);
}

/****************************************************************************/
/*                               fdstrategy                                 */
/****************************************************************************/
Fdstrategy(bp)
	register struct buf *bp;	/* IO operation to perform */
{
	register struct buf *dp;
	long nblocks,blknum;
 	int	unit, type, s;

 	unit = FDUNIT(minor(bp->b_dev));
 	type = FDTYPE(minor(bp->b_dev));

#ifdef FDTEST
printf("fdstrat%d, blk = %d, bcount = %d, addr = %x|",
	unit, bp->b_blkno, bp->b_bcount,bp->b_un.b_addr);
#endif
	if ((unit >= NFD) || (bp->b_blkno < 0)) {
		printf("fdstrat: unit = %d, blkno = %d, bcount = %d\n",
			unit, bp->b_blkno, bp->b_bcount);
		pg("fd:error in fdstrategy");
		bp->b_error = EINVAL;
		bp->b_flags |= B_ERROR;
		goto bad;
	}
	/*
	 * Set up block calculations.
	 */
	blknum = (unsigned long) bp->b_blkno * DEV_BSIZE/FDBLK;
 	nblocks = fd_types[type].size;
	if (blknum + (bp->b_bcount / FDBLK) > nblocks) {
		if (blknum == nblocks) {
			bp->b_resid = bp->b_bcount;
		} else {
			bp->b_error = ENOSPC;
			bp->b_flags |= B_ERROR;
		}
#ifdef FDTEST
printf("fdstrat%d, too big\n");
#endif 
		goto bad;
	}
 	bp->b_cylin = blknum / (fd_types[type].sectrac * 2);
	dp = &fd_unit[unit].head;
	dp->b_step = (fd_types[fd_unit[unit].type].steptrac);
	s = splbio();
	disksort(dp, bp);
	if ((fd_unit[0].head.b_active == 0)
#if NFD > 1
	    && (fd_unit[1].head.b_active == 0)
#endif
	    ) {
#ifdef FDDEBUG
printf("T|");
#endif
		dp->b_active = 1;
		fd_drive = unit;
		fd_track = -1;  /* force seek on first xfer */
		untimeout(fd_turnoff,unit);
		fdstart(unit);		/* start drive if idle */
	}
	splx(s);
	return;

bad:
	biodone(bp);
}

/****************************************************************************/
/*                            motor control stuff                           */
/****************************************************************************/
set_motor(unit,reset)
int unit,reset;
{
	outb(fdc+fdout,unit | (reset ? 0 : 0xC)  | FDMOTOR(0) 
#if NFD > 1
	     | FDMOTOR(1)
#endif
	     );
}

fd_turnoff(unit)
int unit;
{
	fd_unit[unit].motor = 0;
	if (unit) set_motor(0,0);
	else set_motor(1,0);
}

fd_turnon(unit)
int unit;
{
	fd_unit[unit].motor = 1;
	set_motor(unit,0);
}

/****************************************************************************/
/*                             fdc in/out                                   */
/****************************************************************************/
int
in_fdc()
{
	int i;
	while ((i = inb(fdc+fdsts) & (NE7_DIO|NE7_RQM)) != (NE7_DIO|NE7_RQM))
		if (i == NE7_RQM) return -1;
	return inb(fdc+fddata);
}

dump_stat()
{
	int i;
	for(i=0;i<7;i++) {
		fd_status[i] = in_fdc();
		if (fd_status[i] < 0) break;
	}
printf("FD bad status :%lx %lx %lx %lx %lx %lx %lx\n",
	fd_status[0], fd_status[1], fd_status[2], fd_status[3],
	fd_status[4], fd_status[5], fd_status[6] );
}

out_fdc(x)
int x;
{
	int r,errcnt;
	static int maxcnt = 0;
	errcnt = 0;
	do {
		r = (inb(fdc+fdsts) & (NE7_DIO|NE7_RQM));
		if (r== NE7_RQM) break;
		if (r==(NE7_DIO|NE7_RQM)) {
			dump_stat(); /* error: direction. eat up output */
#ifdef FDOTHER
printf("%lx\n",x);
#endif
		}
		/* printf("Error r = %d:",r); */
		errcnt++;
	} while (1);
	if (errcnt > maxcnt) {
		maxcnt = errcnt;
#ifdef FDOTHER
printf("New MAX = %d\n",maxcnt);
#endif
	}
	outb(fdc+fddata,x);
}

/* see if fdc responding */
int
check_fdc()
{
	int i;
	for(i=0;i<100;i++) {
		if (inb(fdc+fdsts)& NE7_RQM) return 0;
	}
	return 1;
}

/****************************************************************************/
/*                           fdopen/fdclose                                 */
/****************************************************************************/
Fdopen(dev, flags)
	dev_t	dev;
	int	flags;
{
 	int unit = FDUNIT(minor(dev));
 	int type = FDTYPE(minor(dev));
	int s;

	printf("fdopen %x %d %d\n", minor(dev), unit, type);
	/* check bounds */
	if (unit >= NFD) return(ENXIO);
	if (type >= NUMTYPES) return(ENXIO);
/*
	if (check_fdc()) return(EBUSY);
*/

	/* Set proper disk type, only allow one type */
	return 0;
}

Fdclose(dev, flags)
	dev_t dev;
{
	return (0);
}

/****************************************************************************/
/*                            fdread/fdwrite                                */
/****************************************************************************/
/*
 * Routines to do raw IO for a unit.