/*
   *  Copyright (C) 1991, 1992  Linus Torvalds
   *
   * This is the low-level hd interrupt support. It traverses the
   * request-list, using interrupts to jump between functions. As
   * all the functions are called within interrupts, we may not
   * sleep. Special care is recommended.
   *
   *  modified by Drew Eckhardt to check nr of hd's from the CMOS.
   *
   *  Thanks to Branko Lankester, lankeste@fwi.uva.nl, who found a bug
   *  in the early extended-partition checks and added DM partitions
   *
   *  IRQ-unmask, drive-id, multiple-mode, support for ">16 heads",
   *  and general streamlining by Mark Lord.
   *
   *  Removed 99% of above. Use Mark's ide driver for those options.
   *  This is now a lightweight ST-506 driver. (Paul Gortmaker)
   *
   *  Modified 1995 Russell King for ARM processor.
   *
   *  Bugfix: max_sectors must be <= 255 or the wheels tend to come
   *  off in a hurry once you queue things up - Paul G. 02/2001
   */
  
  /* Uncomment the following if you want verbose error reports. */
  /* #define VERBOSE_ERRORS */
  
  #include <linux/blkdev.h>
  #include <linux/errno.h>
  #include <linux/signal.h>
  #include <linux/interrupt.h>
  #include <linux/timer.h>
  #include <linux/fs.h>
  #include <linux/kernel.h>
  #include <linux/genhd.h>
  #include <linux/string.h>
  #include <linux/ioport.h>
  #include <linux/init.h>
  #include <linux/blkpg.h>
  #include <linux/ata.h>
  #include <linux/hdreg.h>
  
  #define HD_IRQ 14
  
  #define REALLY_SLOW_IO
  #include <asm/io.h>
  #include <asm/uaccess.h>
  
  #ifdef __arm__
  #undef  HD_IRQ
  #endif
  #include <asm/irq.h>
  #ifdef __arm__
  #define HD_IRQ IRQ_HARDDISK
  #endif
  
  /* Hd controller regster ports */
  
  #define HD_DATA		0x1f0		/* _CTL when writing */
  #define HD_ERROR	0x1f1		/* see err-bits */
  #define HD_NSECTOR	0x1f2		/* nr of sectors to read/write */
  #define HD_SECTOR	0x1f3		/* starting sector */
  #define HD_LCYL		0x1f4		/* starting cylinder */
  #define HD_HCYL		0x1f5		/* high byte of starting cyl */
  #define HD_CURRENT	0x1f6		/* 101dhhhh , d=drive, hhhh=head */
  #define HD_STATUS	0x1f7		/* see status-bits */
  #define HD_FEATURE	HD_ERROR	/* same io address, read=error, write=feature */
  #define HD_PRECOMP	HD_FEATURE	/* obsolete use of this port - predates IDE */
  #define HD_COMMAND	HD_STATUS	/* same io address, read=status, write=cmd */
  
  #define HD_CMD		0x3f6		/* used for resets */
  #define HD_ALTSTATUS	0x3f6		/* same as HD_STATUS but doesn't clear irq */
  
  /* Bits of HD_STATUS */
  #define ERR_STAT		0x01
  #define INDEX_STAT		0x02
  #define ECC_STAT		0x04	/* Corrected error */
  #define DRQ_STAT		0x08
  #define SEEK_STAT		0x10
  #define SERVICE_STAT		SEEK_STAT
  #define WRERR_STAT		0x20
  #define READY_STAT		0x40
  #define BUSY_STAT		0x80
  
  /* Bits for HD_ERROR */
  #define MARK_ERR		0x01	/* Bad address mark */
  #define TRK0_ERR		0x02	/* couldn't find track 0 */
  #define ABRT_ERR		0x04	/* Command aborted */
  #define MCR_ERR			0x08	/* media change request */
  #define ID_ERR			0x10	/* ID field not found */
  #define MC_ERR			0x20	/* media changed */
  #define ECC_ERR			0x40	/* Uncorrectable ECC error */
  #define BBD_ERR			0x80	/* pre-EIDE meaning:  block marked bad */
  #define ICRC_ERR		0x80	/* new meaning:  CRC error during transfer */
  
  static DEFINE_SPINLOCK(hd_lock);
  static struct request_queue *hd_queue;
  static struct request *hd_req;
  
  #define TIMEOUT_VALUE	(6*HZ)
  #define	HD_DELAY	0
  
  #define MAX_ERRORS     16	/* Max read/write errors/sector */
  #define RESET_FREQ      8	/* Reset controller every 8th retry */
  #define RECAL_FREQ      4	/* Recalibrate every 4th retry */
  #define MAX_HD		2
  
  #define STAT_OK		(READY_STAT|SEEK_STAT)
  #define OK_STATUS(s)	(((s)&(STAT_OK|(BUSY_STAT|WRERR_STAT|ERR_STAT)))==STAT_OK)
  
  static void recal_intr(void);
  static void bad_rw_intr(void);
  
  static int reset;
  static int hd_error;
  
  /*
   *  This struct defines the HD's and their types.
   */
  struct hd_i_struct {
  	unsigned int head, sect, cyl, wpcom, lzone, ctl;
  	int unit;
  	int recalibrate;
  	int special_op;
  };
  
  #ifdef HD_TYPE
  static struct hd_i_struct hd_info[] = { HD_TYPE };
  static int NR_HD = ARRAY_SIZE(hd_info);
  #else
  static struct hd_i_struct hd_info[MAX_HD];
  static int NR_HD;
  #endif
  
  static struct gendisk *hd_gendisk[MAX_HD];
  
  static struct timer_list device_timer;
  
  #define TIMEOUT_VALUE (6*HZ)
  
  #define SET_TIMER							\
  	do {								\
  		mod_timer(&device_timer, jiffies + TIMEOUT_VALUE);	\
  	} while (0)
  
  static void (*do_hd)(void) = NULL;
  #define SET_HANDLER(x) \
  if ((do_hd = (x)) != NULL) \
  	SET_TIMER; \
  else \
  	del_timer(&device_timer);
  
  
  #if (HD_DELAY > 0)
  
  #include <linux/i8253.h>
  
  unsigned long last_req;
  
  unsigned long read_timer(void)
  {
  	unsigned long t, flags;
  	int i;
  
  	raw_spin_lock_irqsave(&i8253_lock, flags);
  	t = jiffies * 11932;
  	outb_p(0, 0x43);
  	i = inb_p(0x40);
  	i |= inb(0x40) << 8;
  	raw_spin_unlock_irqrestore(&i8253_lock, flags);
  	return(t - i);
  }
  #endif
  
  static void __init hd_setup(char *str, int *ints)
  {
  	int hdind = 0;
  
  	if (ints[0] != 3)
  		return;
  	if (hd_info[0].head != 0)
  		hdind = 1;
  	hd_info[hdind].head = ints[2];
  	hd_info[hdind].sect = ints[3];
  	hd_info[hdind].cyl = ints[1];
  	hd_info[hdind].wpcom = 0;
  	hd_info[hdind].lzone = ints[1];
  	hd_info[hdind].ctl = (ints[2] > 8 ? 8 : 0);
  	NR_HD = hdind+1;
  }
  
  static bool hd_end_request(int err, unsigned int bytes)
  {
  	if (__blk_end_request(hd_req, err, bytes))
  		return true;
  	hd_req = NULL;
  	return false;
  }
  
  static bool hd_end_request_cur(int err)
  {
  	return hd_end_request(err, blk_rq_cur_bytes(hd_req));
  }
  
  static void dump_status(const char *msg, unsigned int stat)
  {
  	char *name = "hd?";
  	if (hd_req)
  		name = hd_req->rq_disk->disk_name;
  
  #ifdef VERBOSE_ERRORS
  	printk("%s: %s: status=0x%02x { ", name, msg, stat & 0xff);
  	if (stat & BUSY_STAT)	printk("Busy ");
  	if (stat & READY_STAT)	printk("DriveReady ");
  	if (stat & WRERR_STAT)	printk("WriteFault ");
  	if (stat & SEEK_STAT)	printk("SeekComplete ");
  	if (stat & DRQ_STAT)	printk("DataRequest ");
  	if (stat & ECC_STAT)	printk("CorrectedError ");
  	if (stat & INDEX_STAT)	printk("Index ");
  	if (stat & ERR_STAT)	printk("Error ");
  	printk("}
  ");
  	if ((stat & ERR_STAT) == 0) {
  		hd_error = 0;
  	} else {
  		hd_error = inb(HD_ERROR);
  		printk("%s: %s: error=0x%02x { ", name, msg, hd_error & 0xff);
  		if (hd_error & BBD_ERR)		printk("BadSector ");
  		if (hd_error & ECC_ERR)		printk("UncorrectableError ");
  		if (hd_error & ID_ERR)		printk("SectorIdNotFound ");
  		if (hd_error & ABRT_ERR)	printk("DriveStatusError ");
  		if (hd_error & TRK0_ERR)	printk("TrackZeroNotFound ");
  		if (hd_error & MARK_ERR)	printk("AddrMarkNotFound ");
  		printk("}");
  		if (hd_error & (BBD_ERR|ECC_ERR|ID_ERR|MARK_ERR)) {
  			printk(", CHS=%d/%d/%d", (inb(HD_HCYL)<<8) + inb(HD_LCYL),
  				inb(HD_CURRENT) & 0xf, inb(HD_SECTOR));
  			if (hd_req)
  				printk(", sector=%ld", blk_rq_pos(hd_req));
  		}
  		printk("
  ");
  	}
  #else
  	printk("%s: %s: status=0x%02x.
  ", name, msg, stat & 0xff);
  	if ((stat & ERR_STAT) == 0) {
  		hd_error = 0;
  	} else {
  		hd_error = inb(HD_ERROR);
  		printk("%s: %s: error=0x%02x.
  ", name, msg, hd_error & 0xff);
  	}
  #endif
  }
  
  static void check_status(void)
  {
  	int i = inb_p(HD_STATUS);
  
  	if (!OK_STATUS(i)) {
  		dump_status("check_status", i);
  		bad_rw_intr();
  	}
  }
  
  static int controller_busy(void)
  {
  	int retries = 100000;
  	unsigned char status;
  
  	do {
  		status = inb_p(HD_STATUS);
  	} while ((status & BUSY_STAT) && --retries);
  	return status;
  }
  
  static int status_ok(void)
  {
  	unsigned char status = inb_p(HD_STATUS);
  
  	if (status & BUSY_STAT)
  		return 1;	/* Ancient, but does it make sense??? */
  	if (status & WRERR_STAT)
  		return 0;
  	if (!(status & READY_STAT))
  		return 0;
  	if (!(status & SEEK_STAT))
  		return 0;
  	return 1;
  }
  
  static int controller_ready(unsigned int drive, unsigned int head)
  {
  	int retry = 100;
  
  	do {
  		if (controller_busy() & BUSY_STAT)
  			return 0;
  		outb_p(0xA0 | (drive<<4) | head, HD_CURRENT);
  		if (status_ok())
  			return 1;
  	} while (--retry);
  	return 0;
  }
  
  static void hd_out(struct hd_i_struct *disk,
  		   unsigned int nsect,
  		   unsigned int sect,
  		   unsigned int head,
  		   unsigned int cyl,
  		   unsigned int cmd,
  		   void (*intr_addr)(void))
  {
  	unsigned short port;
  
  #if (HD_DELAY > 0)
  	while (read_timer() - last_req < HD_DELAY)
  		/* nothing */;
  #endif
  	if (reset)
  		return;
  	if (!controller_ready(disk->unit, head)) {
  		reset = 1;
  		return;
  	}
  	SET_HANDLER(intr_addr);
  	outb_p(disk->ctl, HD_CMD);
  	port = HD_DATA;
  	outb_p(disk->wpcom >> 2, ++port);
  	outb_p(nsect, ++port);
  	outb_p(sect, ++port);
  	outb_p(cyl, ++port);
  	outb_p(cyl >> 8, ++port);
  	outb_p(0xA0 | (disk->unit << 4) | head, ++port);
  	outb_p(cmd, ++port);
  }
  
  static void hd_request (void);
  
  static int drive_busy(void)
  {
  	unsigned int i;
  	unsigned char c;
  
  	for (i = 0; i < 500000 ; i++) {
  		c = inb_p(HD_STATUS);
  		if ((c & (BUSY_STAT | READY_STAT | SEEK_STAT)) == STAT_OK)
  			return 0;
  	}
  	dump_status("reset timed out", c);
  	return 1;
  }
  
  static void reset_controller(void)
  {
  	int	i;
  
  	outb_p(4, HD_CMD);
  	for (i = 0; i < 1000; i++) barrier();
  	outb_p(hd_info[0].ctl & 0x0f, HD_CMD);
  	for (i = 0; i < 1000; i++) barrier();
  	if (drive_busy())
  		printk("hd: controller still busy
  ");
  	else if ((hd_error = inb(HD_ERROR)) != 1)
  		printk("hd: controller reset failed: %02x
  ", hd_error);
  }
  
  static void reset_hd(void)
  {
  	static int i;
  
  repeat:
  	if (reset) {
  		reset = 0;
  		i = -1;
  		reset_controller();
  	} else {
  		check_status();
  		if (reset)
  			goto repeat;
  	}
  	if (++i < NR_HD) {
  		struct hd_i_struct *disk = &hd_info[i];
  		disk->special_op = disk->recalibrate = 1;
  		hd_out(disk, disk->sect, disk->sect, disk->head-1,
  			disk->cyl, ATA_CMD_INIT_DEV_PARAMS, &reset_hd);
  		if (reset)
  			goto repeat;
  	} else
  		hd_request();
  }
  
  /*
   * Ok, don't know what to do with the unexpected interrupts: on some machines
   * doing a reset and a retry seems to result in an eternal loop. Right now I
   * ignore it, and just set the timeout.
   *
   * On laptops (and "green" PCs), an unexpected interrupt occurs whenever the
   * drive enters "idle", "standby", or "sleep" mode, so if the status looks
   * "good", we just ignore the interrupt completely.
   */
  static void unexpected_hd_interrupt(void)
  {
  	unsigned int stat = inb_p(HD_STATUS);
  
  	if (stat & (BUSY_STAT|DRQ_STAT|ECC_STAT|ERR_STAT)) {
  		dump_status("unexpected interrupt", stat);
  		SET_TIMER;
  	}
  }
  
  /*
   * bad_rw_intr() now tries to be a bit smarter and does things
   * according to the error returned by the controller.
   * -Mika Liljeberg (liljeber@cs.Helsinki.FI)
   */
  static void bad_rw_intr(void)
  {
  	struct request *req = hd_req;
  
  	if (req != NULL) {
  		struct hd_i_struct *disk = req->rq_disk->private_data;
  		if (++req->errors >= MAX_ERRORS || (hd_error & BBD_ERR)) {
  			hd_end_request_cur(-EIO);
  			disk->special_op = disk->recalibrate = 1;
  		} else if (req->errors % RESET_FREQ == 0)
  			reset = 1;
  		else if ((hd_error & TRK0_ERR) || req->errors % RECAL_FREQ == 0)
  			disk->special_op = disk->recalibrate = 1;
  		/* Otherwise just retry */
  	}
  }
  
  static inline int wait_DRQ(void)
  {
  	int retries;
  	int stat;
  
  	for (retries = 0; retries < 100000; retries++) {
  		stat = inb_p(HD_STATUS);
  		if (stat & DRQ_STAT)
  			return 0;
  	}
  	dump_status("wait_DRQ", stat);
  	return -1;
  }
  
  static void read_intr(void)
  {
  	struct request *req;
  	int i, retries = 100000;
  
  	do {
  		i = (unsigned) inb_p(HD_STATUS);
  		if (i & BUSY_STAT)
  			continue;
  		if (!OK_STATUS(i))
  			break;
  		if (i & DRQ_STAT)
  			goto ok_to_read;
  	} while (--retries > 0);
  	dump_status("read_intr", i);
  	bad_rw_intr();
  	hd_request();
  	return;
  
  ok_to_read:
  	req = hd_req;
  	insw(HD_DATA, req->buffer, 256);
  #ifdef DEBUG
  	printk("%s: read: sector %ld, remaining = %u, buffer=%p
  ",
  	       req->rq_disk->disk_name, blk_rq_pos(req) + 1,
  	       blk_rq_sectors(req) - 1, req->buffer+512);
  #endif
  	if (hd_end_request(0, 512)) {
  		SET_HANDLER(&read_intr);
  		return;
  	}
  
  	(void) inb_p(HD_STATUS);
  #if (HD_DELAY > 0)
  	last_req = read_timer();
  #endif
  	hd_request();
  }
  
  static void write_intr(void)
  {
  	struct request *req = hd_req;
  	int i;
  	int retries = 100000;
  
  	do {
  		i = (unsigned) inb_p(HD_STATUS);
  		if (i & BUSY_STAT)
  			continue;
  		if (!OK_STATUS(i))
  			break;
  		if ((blk_rq_sectors(req) <= 1) || (i & DRQ_STAT))
  			goto ok_to_write;
  	} while (--retries > 0);
  	dump_status("write_intr", i);
  	bad_rw_intr();
  	hd_request();
  	return;
  
  ok_to_write:
  	if (hd_end_request(0, 512)) {
  		SET_HANDLER(&write_intr);
  		outsw(HD_DATA, req->buffer, 256);
  		return;
  	}
  
  #if (HD_DELAY > 0)
  	last_req = read_timer();
  #endif
  	hd_request();
  }
  
  static void recal_intr(void)
  {
  	check_status();
  #if (HD_DELAY > 0)
  	last_req = read_timer();
  #endif
  	hd_request();
  }
  
  /*
   * This is another of the error-routines I don't know what to do with. The
   * best idea seems to just set reset, and start all over again.
   */
  static void hd_times_out(unsigned long dummy)
  {
  	char *name;
  
  	do_hd = NULL;
  
  	if (!hd_req)
  		return;
  
  	spin_lock_irq(hd_queue->queue_lock);
  	reset = 1;
  	name = hd_req->rq_disk->disk_name;
  	printk("%s: timeout
  ", name);
  	if (++hd_req->errors >= MAX_ERRORS) {
  #ifdef DEBUG
  		printk("%s: too many errors
  ", name);
  #endif
  		hd_end_request_cur(-EIO);
  	}
  	hd_request();
  	spin_unlock_irq(hd_queue->queue_lock);
  }
  
  static int do_special_op(struct hd_i_struct *disk, struct request *req)
  {
  	if (disk->recalibrate) {
  		disk->recalibrate = 0;
  		hd_out(disk, disk->sect, 0, 0, 0, ATA_CMD_RESTORE, &recal_intr);
  		return reset;
  	}
  	if (disk->head > 16) {
  		printk("%s: cannot handle device with more than 16 heads - giving up
  ", req->rq_disk->disk_name);
  		hd_end_request_cur(-EIO);
  	}
  	disk->special_op = 0;
  	return 1;
  }
  
  /*
   * The driver enables interrupts as much as possible.  In order to do this,
   * (a) the device-interrupt is disabled before entering hd_request(),
   * and (b) the timeout-interrupt is disabled before the sti().
   *
   * Interrupts are still masked (by default) whenever we are exchanging
   * data/cmds with a drive, because some drives seem to have very poor
   * tolerance for latency during I/O. The IDE driver has support to unmask
   * interrupts for non-broken hardware, so use that driver if required.
   */
  static void hd_request(void)
  {
  	unsigned int block, nsect, sec, track, head, cyl;
  	struct hd_i_struct *disk;
  	struct request *req;
  
  	if (do_hd)
  		return;
  repeat:
  	del_timer(&device_timer);
  
  	if (!hd_req) {
  		hd_req = blk_fetch_request(hd_queue);
  		if (!hd_req) {
  			do_hd = NULL;
  			return;
  		}
  	}
  	req = hd_req;
  
  	if (reset) {
  		reset_hd();
  		return;
  	}
  	disk = req->rq_disk->private_data;
  	block = blk_rq_pos(req);
  	nsect = blk_rq_sectors(req);
  	if (block >= get_capacity(req->rq_disk) ||
  	    ((block+nsect) > get_capacity(req->rq_disk))) {
  		printk("%s: bad access: block=%d, count=%d
  ",
  			req->rq_disk->disk_name, block, nsect);
  		hd_end_request_cur(-EIO);
  		goto repeat;
  	}
  
  	if (disk->special_op) {
  		if (do_special_op(disk, req))
  			goto repeat;
  		return;
  	}
  	sec   = block % disk->sect + 1;
  	track = block / disk->sect;
  	head  = track % disk->head;
  	cyl   = track / disk->head;
  #ifdef DEBUG
  	printk("%s: %sing: CHS=%d/%d/%d, sectors=%d, buffer=%p
  ",
  		req->rq_disk->disk_name,
  		req_data_dir(req) == READ ? "read" : "writ",
  		cyl, head, sec, nsect, req->buffer);
  #endif
  	if (req->cmd_type == REQ_TYPE_FS) {
  		switch (rq_data_dir(req)) {
  		case READ:
  			hd_out(disk, nsect, sec, head, cyl, ATA_CMD_PIO_READ,
  				&read_intr);
  			if (reset)
  				goto repeat;
  			break;
  		case WRITE:
  			hd_out(disk, nsect, sec, head, cyl, ATA_CMD_PIO_WRITE,
  				&write_intr);
  			if (reset)
  				goto repeat;
  			if (wait_DRQ()) {
  				bad_rw_intr();
  				goto repeat;
  			}
  			outsw(HD_DATA, req->buffer, 256);
  			break;
  		default:
  			printk("unknown hd-command
  ");
  			hd_end_request_cur(-EIO);
  			break;
  		}
  	}
  }
  
  static void do_hd_request(struct request_queue *q)
  {
  	hd_request();
  }
  
  static int hd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
  {
  	struct hd_i_struct *disk = bdev->bd_disk->private_data;
  
  	geo->heads = disk->head;
  	geo->sectors = disk->sect;
  	geo->cylinders = disk->cyl;
  	return 0;
  }
  
  /*
   * Releasing a block device means we sync() it, so that it can safely
   * be forgotten about...
   */
  
  static irqreturn_t hd_interrupt(int irq, void *dev_id)
  {
  	void (*handler)(void) = do_hd;
  
  	spin_lock(hd_queue->queue_lock);
  
  	do_hd = NULL;
  	del_timer(&device_timer);
  	if (!handler)
  		handler = unexpected_hd_interrupt;
  	handler();
  
  	spin_unlock(hd_queue->queue_lock);
  
  	return IRQ_HANDLED;
  }
  
  static const struct block_device_operations hd_fops = {
  	.getgeo =	hd_getgeo,
  };
  
  /*
   * This is the hard disk IRQ description. The IRQF_DISABLED in sa_flags
   * means we run the IRQ-handler with interrupts disabled:  this is bad for
   * interrupt latency, but anything else has led to problems on some
   * machines.
   *
   * We enable interrupts in some of the routines after making sure it's
   * safe.
   */
  
  static int __init hd_init(void)
  {
  	int drive;
  
  	if (register_blkdev(HD_MAJOR, "hd"))
  		return -1;
  
  	hd_queue = blk_init_queue(do_hd_request, &hd_lock);
  	if (!hd_queue) {
  		unregister_blkdev(HD_MAJOR, "hd");
  		return -ENOMEM;
  	}
  
  	blk_queue_max_hw_sectors(hd_queue, 255);
  	init_timer(&device_timer);
  	device_timer.function = hd_times_out;
  	blk_queue_logical_block_size(hd_queue, 512);
  
  	if (!NR_HD) {
  		/*
  		 * We don't know anything about the drive.  This means
  		 * that you *MUST* specify the drive parameters to the
  		 * kernel yourself.
  		 *
  		 * If we were on an i386, we used to read this info from
  		 * the BIOS or CMOS.  This doesn't work all that well,
  		 * since this assumes that this is a primary or secondary
  		 * drive, and if we're using this legacy driver, it's
  		 * probably an auxiliary controller added to recover
  		 * legacy data off an ST-506 drive.  Either way, it's
  		 * definitely safest to have the user explicitly specify
  		 * the information.
  		 */
  		printk("hd: no drives specified - use hd=cyl,head,sectors"
  			" on kernel command line
  ");
  		goto out;
  	}
  
  	for (drive = 0 ; drive < NR_HD ; drive++) {
  		struct gendisk *disk = alloc_disk(64);
  		struct hd_i_struct *p = &hd_info[drive];
  		if (!disk)
  			goto Enomem;
  		disk->major = HD_MAJOR;
  		disk->first_minor = drive << 6;
  		disk->fops = &hd_fops;
  		sprintf(disk->disk_name, "hd%c", 'a'+drive);
  		disk->private_data = p;
  		set_capacity(disk, p->head * p->sect * p->cyl);
  		disk->queue = hd_queue;
  		p->unit = drive;
  		hd_gendisk[drive] = disk;
  		printk("%s: %luMB, CHS=%d/%d/%d
  ",
  			disk->disk_name, (unsigned long)get_capacity(disk)/2048,
  			p->cyl, p->head, p->sect);
  	}
  
  	if (request_irq(HD_IRQ, hd_interrupt, IRQF_DISABLED, "hd", NULL)) {
  		printk("hd: unable to get IRQ%d for the hard disk driver
  ",
  			HD_IRQ);
  		goto out1;
  	}
  	if (!request_region(HD_DATA, 8, "hd")) {
  		printk(KERN_WARNING "hd: port 0x%x busy
  ", HD_DATA);
  		goto out2;
  	}
  	if (!request_region(HD_CMD, 1, "hd(cmd)")) {
  		printk(KERN_WARNING "hd: port 0x%x busy
  ", HD_CMD);
  		goto out3;
  	}
  
  	/* Let them fly */
  	for (drive = 0; drive < NR_HD; drive++)
  		add_disk(hd_gendisk[drive]);
  
  	return 0;
  
  out3:
  	release_region(HD_DATA, 8);
  out2:
  	free_irq(HD_IRQ, NULL);
  out1:
  	for (drive = 0; drive < NR_HD; drive++)
  		put_disk(hd_gendisk[drive]);
  	NR_HD = 0;
  out:
  	del_timer(&device_timer);
  	unregister_blkdev(HD_MAJOR, "hd");
  	blk_cleanup_queue(hd_queue);
  	return -1;
  Enomem:
  	while (drive--)
  		put_disk(hd_gendisk[drive]);
  	goto out;
  }
  
  static int __init parse_hd_setup(char *line)
  {
  	int ints[6];
  
  	(void) get_options(line, ARRAY_SIZE(ints), ints);
  	hd_setup(NULL, ints);
  
  	return 1;
  }
  __setup("hd=", parse_hd_setup);
  
  late_initcall(hd_init);