fd1772.c

上传linux-jx2410的源代码

static __inline__ void set_head_settle_flag(void)
{
	HeadSettleFlag = FDC1772CMDADD_E;
}

static __inline__ int get_head_settle_flag(void)
{
	int tmp = HeadSettleFlag;
	HeadSettleFlag = 0;
	return (tmp);
}




/* General Interrupt Handling */

static void (*FloppyIRQHandler) (int status) = NULL;

static void floppy_irqconsequencehandler(void)
{
	unsigned char status;
	void (*handler) (int);

	fdc1772_fdc_int_done = 0;

	handler = FloppyIRQHandler;
	FloppyIRQHandler = NULL;

	if (handler) {
		nop();
		status = (unsigned char) fdc1772_comendstatus;
		DPRINT(("FDC1772 irq, status = %02x handler = %08lx\n", (unsigned int) status, (unsigned long) handler));
		handler(status);
	} else {
		DPRINT(("FDC1772 irq, no handler status=%02x\n", fdc1772_comendstatus));
	}
	DPRINT(("FDC1772 irq: end of floppy_irq\n"));
}


/* Error handling: If some error happened, retry some times, then
 * recalibrate, then try again, and fail after MAX_ERRORS.
 */

static void fd_error(void)
{
	printk("FDC1772: fd_error\n");
	/*panic("fd1772: fd_error"); *//* DAG tmp */
	if (QUEUE_EMPTY)
		return;
	CURRENT->errors++;
	if (CURRENT->errors >= MAX_ERRORS) {
		printk("fd%d: too many errors.\n", SelectedDrive);
		end_request(0);
	} else if (CURRENT->errors == RECALIBRATE_ERRORS) {
		printk("fd%d: recalibrating\n", SelectedDrive);
		if (SelectedDrive != -1)
			unit[SelectedDrive].track = -1;
	}
	redo_fd_request();
}



#define	SET_IRQ_HANDLER(proc) do { FloppyIRQHandler = (proc); } while(0)


/* do_fd_action() is the general procedure for a fd request: All
 * required parameter settings (drive select, side select, track
 * position) are checked and set if needed. For each of these
 * parameters and the actual reading or writing exist two functions:
 * one that starts the setting (or skips it if possible) and one
 * callback for the "done" interrupt. Each done func calls the next
 * set function to propagate the request down to fd_rwsec_done().
 */

static void do_fd_action(int drive)
{
	DPRINT(("do_fd_action unit[drive].track=%d\n", unit[drive].track));

#ifdef TRACKBUFFER
repeat:

	if (IS_BUFFERED( drive, ReqSide, ReqTrack )) {
		if (ReqCmd == READ) {
			copy_buffer( SECTOR_BUFFER(ReqSector), ReqData );
			if (++ReqCnt < CURRENT->current_nr_sectors) {
				/* read next sector */
				setup_req_params( drive );
				goto repeat;
			} else {
				/* all sectors finished */
				CURRENT->nr_sectors -= CURRENT->current_nr_sectors;
				CURRENT->sector += CURRENT->current_nr_sectors;
				end_request( 1 );
				redo_fd_request();
				return;
			}
		} else {
			/* cmd == WRITE, pay attention to track buffer
			 * consistency! */
			copy_buffer( ReqData, SECTOR_BUFFER(ReqSector) );
		}
	}
#endif

	if (SelectedDrive != drive) {
		/*unit[drive].track = -1; DAG */
		fd_select_drive(drive);
	};


	if (unit[drive].track == -1)
		fd_calibrate();
	else if (unit[drive].track != ReqTrack << unit[drive].disktype->stretch)
		fd_seek();
	else
		fd_rwsec();
}


/* Seek to track 0 if the current track is unknown */

static void fd_calibrate(void)
{
	DPRINT(("fd_calibrate\n"));
	if (unit[SelectedDrive].track >= 0) {
		fd_calibrate_done(0);
		return;
	}
	DPRINT(("fd_calibrate (after track compare)\n"));
	SET_IRQ_HANDLER(fd_calibrate_done);
	/* we can't verify, since the speed may be incorrect */
	FDC1772_WRITE(FDC1772REG_CMD, FDC1772CMD_RESTORE | unit[SelectedDrive].steprate);

	NeedSeek = 1;
	MotorOn = 1;
	START_TIMEOUT();
	/* wait for IRQ */
}


static void fd_calibrate_done(int status)
{
	DPRINT(("fd_calibrate_done()\n"));
	STOP_TIMEOUT();

	/* set the correct speed now */
	if (status & FDC1772STAT_RECNF) {
		printk("fd%d: restore failed\n", SelectedDrive);
		fd_error();
	} else {
		unit[SelectedDrive].track = 0;
		fd_seek();
	}
}


/* Seek the drive to the requested track. The drive must have been
 * calibrated at some point before this.
 */

static void fd_seek(void)
{
	unsigned long flags;
	DPRINT(("fd_seek() to track %d (unit[SelectedDrive].track=%d)\n", ReqTrack,
		unit[SelectedDrive].track));
	if (unit[SelectedDrive].track == ReqTrack <<
	    unit[SelectedDrive].disktype->stretch) {
		fd_seek_done(0);
		return;
	}
	FDC1772_WRITE(FDC1772REG_DATA, ReqTrack <<
		      unit[SelectedDrive].disktype->stretch);
	udelay(25);
	save_flags(flags);
	clf();
	SET_IRQ_HANDLER(fd_seek_done);
	FDC1772_WRITE(FDC1772REG_CMD, FDC1772CMD_SEEK | unit[SelectedDrive].steprate |
		/* DAG */
		(MotorOn?FDC1772CMDADD_H:0));

	restore_flags(flags);
	MotorOn = 1;
	set_head_settle_flag();
	START_TIMEOUT();
	/* wait for IRQ */
}


static void fd_seek_done(int status)
{
	DPRINT(("fd_seek_done()\n"));
	STOP_TIMEOUT();

	/* set the correct speed */
	if (status & FDC1772STAT_RECNF) {
		printk("fd%d: seek error (to track %d)\n",
		       SelectedDrive, ReqTrack);
		/* we don't know exactly which track we are on now! */
		unit[SelectedDrive].track = -1;
		fd_error();
	} else {
		unit[SelectedDrive].track = ReqTrack <<
		    unit[SelectedDrive].disktype->stretch;
		NeedSeek = 0;
		fd_rwsec();
	}
}


/* This does the actual reading/writing after positioning the head
 * over the correct track.
 */

#ifdef TRACKBUFFER
static int MultReadInProgress = 0;
#endif


static void fd_rwsec(void)
{
	unsigned long paddr, flags;
	unsigned int rwflag, old_motoron;
	unsigned int track;

	DPRINT(("fd_rwsec(), Sec=%d, Access=%c\n", ReqSector, ReqCmd == WRITE ? 'w' : 'r'));
	if (ReqCmd == WRITE) {
		/*cache_push( (unsigned long)ReqData, 512 ); */
		paddr = (unsigned long) ReqData;
		rwflag = 0x100;
	} else {
		paddr = (unsigned long) PhysDMABuffer;
#ifdef TRACKBUFFER
		if (read_track)
			paddr = (unsigned long)PhysTrackBuffer;
#endif
		rwflag = 0;
	}

	DPRINT(("fd_rwsec() before sidesel rwflag=%d sec=%d trk=%d\n", rwflag,
		ReqSector, FDC1772_READ(FDC1772REG_TRACK)));
	fd_select_side(ReqSide);

	/*DPRINT(("fd_rwsec() before start sector \n")); */
	/* Start sector of this operation */
#ifdef TRACKBUFFER
	FDC1772_WRITE( FDC1772REG_SECTOR, !read_track ? ReqSector : 1 );
#else
	FDC1772_WRITE( FDC1772REG_SECTOR, ReqSector );
#endif

	/* Cheat for track if stretch != 0 */
	if (unit[SelectedDrive].disktype->stretch) {
		track = FDC1772_READ(FDC1772REG_TRACK);
		FDC1772_WRITE(FDC1772REG_TRACK, track >>
			      unit[SelectedDrive].disktype->stretch);
	}
	udelay(25);

	DPRINT(("fd_rwsec() before setup DMA \n"));
	/* Setup DMA - Heavily modified by DAG */
	save_flags(flags);
	clf();
	disable_dma(FLOPPY_DMA);
	set_dma_mode(FLOPPY_DMA, rwflag ? DMA_MODE_WRITE : DMA_MODE_READ);
	set_dma_addr(FLOPPY_DMA, (long) paddr);		/* DAG - changed from Atari specific */
#ifdef TRACKBUFFER
	set_dma_count(FLOPPY_DMA,(!read_track ? 1 : unit[SelectedDrive].disktype->spt)*512);
#else
	set_dma_count(FLOPPY_DMA, 512);		/* Block/sector size - going to have to change */
#endif
	SET_IRQ_HANDLER(fd_rwsec_done);
	/* Turn on dma int */
	enable_dma(FLOPPY_DMA);
	/* Now give it something to do */
	FDC1772_WRITE(FDC1772REG_CMD, (rwflag ? (FDC1772CMD_WRSEC | FDC1772CMDADD_P) : 
#ifdef TRACKBUFFER
	      (FDC1772CMD_RDSEC | (read_track ? FDC1772CMDADD_M : 0) |
	      /* Hmm - the idea here is to stop the FDC spinning the disc
	      up when we know that we already still have it spinning */
	      (MotorOn?FDC1772CMDADD_H:0))
#else
	      FDC1772CMD_RDSEC
#endif
		));

	restore_flags(flags);
	DPRINT(("fd_rwsec() after DMA setup flags=0x%08x\n", flags));
	/*sti(); *//* DAG - Hmm */
	/* Hmm - should do something DAG */
	old_motoron = MotorOn;
	MotorOn = 1;
	NeedSeek = 1;

	/* wait for interrupt */

#ifdef TRACKBUFFER
	if (read_track) {
		/*
		 * If reading a whole track, wait about one disk rotation and
		 * then check if all sectors are read. The FDC will even
		 * search for the first non-existant sector and need 1 sec to
		 * recognise that it isn't present :-(
		 */
		/* 1 rot. + 5 rot.s if motor was off  */
		mod_timer(&readtrack_timer, jiffies + HZ/5 + (old_motoron ? 0 : HZ));
		DPRINT(("Setting readtrack_timer to %d @ %d\n",
			readtrack_timer.expires,jiffies));
		MultReadInProgress = 1;
	}
#endif

	/*DPRINT(("fd_rwsec() before START_TIMEOUT \n")); */
	START_TIMEOUT();
	/*DPRINT(("fd_rwsec() after START_TIMEOUT \n")); */
}


#ifdef TRACKBUFFER

static void fd_readtrack_check(unsigned long dummy)
{
	unsigned long flags, addr;
	extern unsigned char *fdc1772_dataaddr;

	DPRINT(("fd_readtrack_check @ %d\n",jiffies));

	save_flags(flags);
	clf();

	del_timer( &readtrack_timer );

	if (!MultReadInProgress) {
		/* This prevents a race condition that could arise if the
		 * interrupt is triggered while the calling of this timer
		 * callback function takes place. The IRQ function then has
		 * already cleared 'MultReadInProgress'  when control flow
		 * gets here.
		 */
		restore_flags(flags);
		return;
	}

	/* get the current DMA address */
	addr=(unsigned long)fdc1772_dataaddr; /* DAG - ? */
	DPRINT(("fd_readtrack_check: addr=%x PhysTrackBuffer=%x\n",addr,PhysTrackBuffer));

	if (addr >= (unsigned int)PhysTrackBuffer + unit[SelectedDrive].disktype->spt*512) {
		/* already read enough data, force an FDC interrupt to stop
		 * the read operation
		 */
		SET_IRQ_HANDLER( NULL );
		restore_flags(flags);
		DPRINT(("fd_readtrack_check(): done\n"));
		FDC1772_WRITE( FDC1772REG_CMD, FDC1772CMD_FORCI );
		udelay(25);

		/* No error until now -- the FDC would have interrupted
		 * otherwise!
		 */
		fd_rwsec_done( 0 );
	} else {
		/* not yet finished, wait another tenth rotation */
		restore_flags(flags);
		DPRINT(("fd_readtrack_check(): not yet finished\n"));
		readtrack_timer.expires = jiffies + HZ/5/10;
		add_timer( &readtrack_timer );
	}
}

#endif

static void fd_rwsec_done(int status)
{
	unsigned int track;

	DPRINT(("fd_rwsec_done() status=%d @ %d\n", status,jiffies));

#ifdef TRACKBUFFER
	if (read_track && !MultReadInProgress)
		return;

	MultReadInProgress = 0;

	STOP_TIMEOUT();

	if (read_track)
		del_timer( &readtrack_timer );
#endif


	/* Correct the track if stretch != 0 */
	if (unit[SelectedDrive].disktype->stretch) {
		track = FDC1772_READ(FDC1772REG_TRACK);
		FDC1772_WRITE(FDC1772REG_TRACK, track <<
			      unit[SelectedDrive].disktype->stretch);
	}
	if (ReqCmd == WRITE && (status & FDC1772STAT_WPROT)) {
		printk("fd%d: is write protected\n", SelectedDrive);
		goto err_end;
	}
	if ((status & FDC1772STAT_RECNF)
#ifdef TRACKBUFFER
	    /* RECNF is no error after a multiple read when the FDC
	     * searched for a non-existant sector!
	     */
	    && !(read_track &&
	       FDC1772_READ(FDC1772REG_SECTOR) > unit[SelectedDrive].disktype->spt)
#endif
	    ) {
		if (Probing) {
			if (unit[SelectedDrive].disktype > disk_type) {
				/* try another disk type */
				unit[SelectedDrive].disktype--;
				floppy_sizes[SelectedDrive]
				    = unit[SelectedDrive].disktype->blocks >> 1;
			} else
				Probing = 0;
		} else {
			/* record not found, but not probing. Maybe stretch wrong ? Restart probing */
			if (unit[SelectedDrive].autoprobe) {
				unit[SelectedDrive].disktype = disk_type + NUM_DISK_TYPES - 1;
				floppy_sizes[SelectedDrive]
				    = unit[SelectedDrive].disktype->blocks >> 1;
				Probing = 1;
			}
		}
		if (Probing) {
			setup_req_params(SelectedDrive);
#ifdef TRACKBUFFER
			BufferDrive = -1;
#endif
			do_fd_action(SelectedDrive);
			return;
		}
		printk("fd%d: sector %d not found (side %d, track %d)\n",
		       SelectedDrive, FDC1772_READ(FDC1772REG_SECTOR), ReqSide, ReqTrack);
		goto err_end;
	}
	if (status & FDC1772STAT_CRC) {
		printk("fd%d: CRC error (side %d, track %d, sector %d)\n",
		       SelectedDrive, ReqSide, ReqTrack, FDC1772_READ(FDC1772REG_SECTOR));
		goto err_end;
	}
	if (status & FDC1772STAT_LOST) {
		printk("fd%d: lost data (side %d, track %d, sector %d)\n",
		       SelectedDrive, ReqSide, ReqTrack, FDC1772_READ(FDC1772REG_SECTOR));
		goto err_end;
	}
	Probing = 0;

	if (ReqCmd == READ) {
#ifdef TRACKBUFFER
		if (!read_track) {
			/*cache_clear (PhysDMABuffer, 512);*/
			copy_buffer (DMABuffer, ReqData);
		} else {
			/*cache_clear (PhysTrackBuffer, FD1772_MAX_SECTORS * 512);*/
			BufferDrive = SelectedDrive;
			BufferSide  = ReqSide;
			BufferTrack = ReqTrack;
			copy_buffer (SECTOR_BUFFER (ReqSector), ReqData);
		}
#else
		/*cache_clear( PhysDMABuffer, 512 ); */
		copy_buffer(DMABuffer, ReqData);
#endif
	}
	if (++ReqCnt < CURRENT->current_nr_sectors) {
		/* read next sector */
		setup_req_params(SelectedDrive);
		do_fd_action(SelectedDrive);
	} else {
		/* all sectors finished */
		CURRENT->nr_sectors -= CURRENT->current_nr_sectors;
		CURRENT->sector += CURRENT->current_nr_sectors;
		end_request(1);
		redo_fd_request();
	}
	return;

err_end:
#ifdef TRACKBUFFER
	BufferDrive = -1;
#endif

	fd_error();
}


static void fd_times_out(unsigned long dummy)
{
	SET_IRQ_HANDLER(NULL);
	/* If the timeout occurred while the readtrack_check timer was
	 * active, we need to cancel it, else bad things will happen */
	del_timer( &readtrack_timer ); 
	FDC1772_WRITE(FDC1772REG_CMD, FDC1772CMD_FORCI);
	udelay(25);

	printk("floppy timeout\n");
	STOP_TIMEOUT();		/* hmm - should we do this ? */
	fd_error();
}


/* The (noop) seek operation here is needed to make the WP bit in the
 * FDC1772 status register accessible for check_change. If the last disk
 * operation would have been a RDSEC, this bit would always read as 0
 * no matter what :-( To save time, the seek goes to the track we're
 * already on.
 */

static void finish_fdc(void)
{
	/* DAG - just try without this dummy seek! */
	finish_fdc_done(0);
	return;

	if (!NeedSeek) {
		finish_fdc_done(0);
	} else {
		DPRINT(("finish_fdc: dummy seek started\n"));
		FDC1772_WRITE(FDC1772REG_DATA, unit[SelectedDrive].track);
		SET_IRQ_HANDLER(finish_fdc_done);
		FDC1772_WRITE(FDC1772REG_CMD, FDC1772CMD_SEEK);
		MotorOn = 1;
		START_TIMEOUT();
		/* we must wait for the IRQ here, because the ST-DMA is
		 * released immediatly afterwards and the interrupt may be
		 * delivered to the wrong driver.
		 */
	}
}


static void finish_fdc_done(int dummy)
{
	unsigned long flags;

	DPRINT(("finish_fdc_done entered\n"));