mfmhd.c

linux-2.6.15.6

}

static void do_mfm_request(request_queue_t *q)
{
	DBG("do_mfm_request: about to mfm_request\n");
	mfm_request();
}

static void mfm_interrupt_handler(int unused, void *dev_id, struct pt_regs *regs)
{
	void (*handler) (void) = do_mfm;

	do_mfm = NULL;

	DBG("mfm_interrupt_handler (handler=0x%p)\n", handler);

	mfm_status = inw(MFM_STATUS);

	/* If CPR (Command Parameter Reject) and not busy it means that the command
	   has some return message to give us */
	if ((mfm_status & (STAT_CPR | STAT_BSY)) == STAT_CPR) {
		int len = 0;
		while (len < 16) {
			int in;
			in = inw(MFM_DATAIN);
			result[len++] = in >> 8;
			result[len++] = in;
		}
	}
	if (handler) {
		handler();
		return;
	}
	outw (CMD_RCAL, MFM_COMMAND);	/* Clear interrupt condition */
	printk ("mfm: unexpected interrupt - status = ");
	print_status ();
	while (1);
}





/*
 * Tell the user about the drive if we decided it exists.
 */
static void mfm_geometry(int drive)
{
	struct mfm_info *p = mfm_info + drive;
	struct gendisk *disk = mfm_gendisk[drive];
	disk->private_data = p;
	if (p->cylinders)
		printk ("%s: %dMB CHS=%d/%d/%d LCC=%d RECOMP=%d\n",
			disk->disk_name,
			p->cylinders * p->heads * p->sectors / 4096,
			p->cylinders, p->heads, p->sectors,
			p->lowcurrent, p->precomp);
	set_capacity(disk, p->cylinders * p->heads * p->sectors / 2);
}

#ifdef CONFIG_BLK_DEV_MFM_AUTODETECT
/*
 * Attempt to detect a drive and find its geometry.  The drive has already been
 * specified...
 *
 * We first recalibrate the disk, then try to probe sectors, heads and then
 * cylinders.  NOTE! the cylinder probe may break drives.  The xd disk driver
 * does something along these lines, so I assume that most drives are up to
 * this mistreatment...
 */
static int mfm_detectdrive (int drive)
{
	unsigned int mingeo[3], maxgeo[3];
	unsigned int attribute, need_recal = 1;
	unsigned char cmdb[8];

	memset (mingeo, 0, sizeof (mingeo));
	maxgeo[0] = mfm_info[drive].sectors;
	maxgeo[1] = mfm_info[drive].heads;
	maxgeo[2] = mfm_info[drive].cylinders;

	cmdb[0] = drive + 1;
	cmdb[6] = 0;
	cmdb[7] = 1;
	for (attribute = 0; attribute < 3; attribute++) {
		while (mingeo[attribute] != maxgeo[attribute]) {
			unsigned int variable;

			variable = (maxgeo[attribute] + mingeo[attribute]) >> 1;
			cmdb[1] = cmdb[2] = cmdb[3] = cmdb[4] = cmdb[5] = 0;

			if (need_recal) {
				int tries = 5;

				do {
					issue_command (CMD_RCLB, cmdb, 2);
					wait_for_completion ();
					wait_for_command_end ();
					if  (result[1] == 0x20)
						break;
				} while (result[1] && --tries);
				if (result[1]) {
					outw (CMD_RCAL, MFM_COMMAND);
					return 0;
				}
				need_recal = 0;
			}

			switch (attribute) {
			case 0:
				cmdb[5] = variable;
				issue_command (CMD_CMPD, cmdb, 8);
				break;
			case 1:
				cmdb[1] = variable;
				cmdb[4] = variable;
				issue_command (CMD_CMPD, cmdb, 8);
				break;
			case 2:
				cmdb[2] = variable >> 8;
				cmdb[3] = variable;
				issue_command (CMD_SEK, cmdb, 4);
				break;
			}
			wait_for_completion ();
			wait_for_command_end ();

			switch (result[1]) {
			case 0x00:
			case 0x50:
				mingeo[attribute] = variable + 1;
				break;

			case 0x20:
				outw (CMD_RCAL, MFM_COMMAND);
				return 0;

			case 0x24:
				need_recal = 1;
			default:
				maxgeo[attribute] = variable;
				break;
			}
		}
	}
	mfm_info[drive].cylinders  = mingeo[2];
	mfm_info[drive].lowcurrent = mingeo[2];
	mfm_info[drive].precomp    = mingeo[2] / 2;
	mfm_info[drive].heads 	   = mingeo[1];
	mfm_info[drive].sectors	   = mingeo[0];
	outw (CMD_RCAL, MFM_COMMAND);
	return 1;
}
#endif

/*
 * Initialise all drive information for this controller.
 */
static int mfm_initdrives(void)
{
	int drive;

	if (number_mfm_drives > MFM_MAXDRIVES) {
		number_mfm_drives = MFM_MAXDRIVES;
		printk("No. of ADFS MFM drives is greater than MFM_MAXDRIVES - you can't have that many!\n");
	}

	for (drive = 0; drive < number_mfm_drives; drive++) {
		mfm_info[drive].lowcurrent = 1;
		mfm_info[drive].precomp    = 1;
		mfm_info[drive].cylinder   = -1;
		mfm_info[drive].errors.recal  = 0;
		mfm_info[drive].errors.report = 0;
		mfm_info[drive].errors.abort  = 4;

#ifdef CONFIG_BLK_DEV_MFM_AUTODETECT
		mfm_info[drive].cylinders  = 1024;
		mfm_info[drive].heads	   = 8;
		mfm_info[drive].sectors	   = 64;
		{
			unsigned char cmdb[16];

			mfm_setupspecify (drive, cmdb);
			cmdb[1] &= ~0x81;
			issue_command (CMD_SPC, cmdb, 16);
			wait_for_completion ();
			if (!mfm_detectdrive (drive)) {
				mfm_info[drive].cylinders = 0;
				mfm_info[drive].heads     = 0;
				mfm_info[drive].sectors   = 0;
			}
			cmdb[0] = cmdb[1] = 0;
			issue_command (CMD_CKV, cmdb, 2);
		}
#else
		mfm_info[drive].cylinders  = 1;	/* its going to have to figure it out from the partition info */
		mfm_info[drive].heads      = 4;
		mfm_info[drive].sectors    = 32;
#endif
	}
	return number_mfm_drives;
}



/*
 * The 'front' end of the mfm driver follows...
 */

static int mfm_ioctl(struct inode *inode, struct file *file, u_int cmd, u_long arg)
{
	struct mfm_info *p = inode->i_bdev->bd_disk->private_data;
	struct hd_geometry *geo = (struct hd_geometry *) arg;
	if (cmd != HDIO_GETGEO)
		return -EINVAL;
	if (!arg)
		return -EINVAL;
	if (put_user (p->heads, &geo->heads))
		return -EFAULT;
	if (put_user (p->sectors, &geo->sectors))
		return -EFAULT;
	if (put_user (p->cylinders, &geo->cylinders))
		return -EFAULT;
	if (put_user (get_start_sect(inode->i_bdev), &geo->start))
		return -EFAULT;
	return 0;
}

/*
 * This is to handle various kernel command line parameters
 * specific to this driver.
 */
void mfm_setup(char *str, int *ints)
{
	return;
}

/*
 * Set the CHS from the ADFS boot block if it is present.  This is not ideal
 * since if there are any non-ADFS partitions on the disk, this won't work!
 * Hence, I want to get rid of this...
 */
void xd_set_geometry(struct block_device *bdev, unsigned char secsptrack,
			unsigned char heads, unsigned int secsize)
{
	struct mfm_info *p = bdev->bd_disk->private_data;
	int drive = p - mfm_info;
	unsigned long disksize = bdev->bd_inode->i_size;

	if (p->cylinders == 1) {
		p->sectors = secsptrack;
		p->heads = heads;
		p->cylinders = discsize / (secsptrack * heads * secsize);

		if ((heads < 1) || (p->cylinders > 1024)) {
			printk("%s: Insane disc shape! Setting to 512/4/32\n",
				bdev->bd_disk->disk_name);

			/* These values are fairly arbitary, but are there so that if your
			 * lucky you can pick apart your disc to find out what is going on -
			 * I reckon these figures won't hurt MOST drives
			 */
			p->sectors = 32;
			p->heads = 4;
			p->cylinders = 512;
		}
		if (raw_cmd.dev == drive)
			mfm_specify ();
		mfm_geometry (drive);
	}
}

static struct block_device_operations mfm_fops =
{
	.owner		= THIS_MODULE,
	.ioctl		= mfm_ioctl,
};

/*
 * See if there is a controller at the address presently at mfm_addr
 *
 * We check to see if the controller is busy - if it is, we abort it first,
 * and check that the chip is no longer busy after at least 180 clock cycles.
 * We then issue a command and check that the BSY or CPR bits are set.
 */
static int mfm_probecontroller (unsigned int mfm_addr)
{
	if (inw (MFM_STATUS) & STAT_BSY) {
		outw (CMD_ABT, MFM_COMMAND);
		udelay (50);
		if (inw (MFM_STATUS) & STAT_BSY)
			return 0;
	}

	if (inw (MFM_STATUS) & STAT_CED)
		outw (CMD_RCAL, MFM_COMMAND);

	outw (CMD_SEK, MFM_COMMAND);

	if (inw (MFM_STATUS) & (STAT_BSY | STAT_CPR)) {
		unsigned int count = 2000;
		while (inw (MFM_STATUS) & STAT_BSY) {
			udelay (500);
			if (!--count)
				return 0;
		}

		outw (CMD_RCAL, MFM_COMMAND);
	}
	return 1;
}

static int mfm_do_init(unsigned char irqmask)
{
	int i, ret;

	printk("mfm: found at address %08X, interrupt %d\n", mfm_addr, mfm_irq);

	ret = -EBUSY;
	if (!request_region (mfm_addr, 10, "mfm"))
		goto out1;

	ret = register_blkdev(MAJOR_NR, "mfm");
	if (ret)
		goto out2;

	/* Stuff for the assembler routines to get to */
	hdc63463_baseaddress	= ioaddr(mfm_addr);
	hdc63463_irqpolladdress	= mfm_IRQPollLoc;
	hdc63463_irqpollmask	= irqmask;

	mfm_queue = blk_init_queue(do_mfm_request, &mfm_lock);
	if (!mfm_queue)
		goto out2a;

	Busy = 0;
	lastspecifieddrive = -1;

	mfm_drives = mfm_initdrives();
	if (!mfm_drives) {
		ret = -ENODEV;
		goto out3;
	}
	
	for (i = 0; i < mfm_drives; i++) {
		struct gendisk *disk = alloc_disk(64);
		if (!disk)
			goto Enomem;
		disk->major = MAJOR_NR;
		disk->first_minor = i << 6;
		disk->fops = &mfm_fops;
		sprintf(disk->disk_name, "mfm%c", 'a'+i);
		mfm_gendisk[i] = disk;
	}

	printk("mfm: detected %d hard drive%s\n", mfm_drives,
				mfm_drives == 1 ? "" : "s");
	ret = request_irq(mfm_irq, mfm_interrupt_handler, SA_INTERRUPT, "MFM harddisk", NULL);
	if (ret) {
		printk("mfm: unable to get IRQ%d\n", mfm_irq);
		goto out4;
	}

	if (mfm_irqenable)
		outw(0x80, mfm_irqenable);	/* Required to enable IRQs from MFM podule */

	for (i = 0; i < mfm_drives; i++) {
		mfm_geometry(i);
		mfm_gendisk[i]->queue = mfm_queue;
		add_disk(mfm_gendisk[i]);
	}
	return 0;

out4:
	for (i = 0; i < mfm_drives; i++)
		put_disk(mfm_gendisk[i]);
out3:
	blk_cleanup_queue(mfm_queue);
out2a:
	unregister_blkdev(MAJOR_NR, "mfm");
out2:
	release_region(mfm_addr, 10);
out1:
	return ret;
Enomem:
	while (i--)
		put_disk(mfm_gendisk[i]);
	goto out3;
}

static void mfm_do_exit(void)
{
	int i;

	free_irq(mfm_irq, NULL);
	for (i = 0; i < mfm_drives; i++) {
		del_gendisk(mfm_gendisk[i]);
		put_disk(mfm_gendisk[i]);
	}
	blk_cleanup_queue(mfm_queue);
	unregister_blkdev(MAJOR_NR, "mfm");
	if (mfm_addr)
		release_region(mfm_addr, 10);
}

static int __devinit mfm_probe(struct expansion_card *ec, struct ecard_id *id)
{
	if (mfm_addr)
		return -EBUSY;

	mfm_addr	= ecard_address(ec, ECARD_IOC, ECARD_MEDIUM) + 0x800;
	mfm_IRQPollLoc	= ioaddr(mfm_addr + 0x400);
	mfm_irqenable	= mfm_IRQPollLoc;
	mfm_irq		= ec->irq;

	return mfm_do_init(0x08);
}

static void __devexit mfm_remove(struct expansion_card *ec)
{
	outw (0, mfm_irqenable);	/* Required to enable IRQs from MFM podule */
	mfm_do_exit();
}

static const struct ecard_id mfm_cids[] = {
	{ MANU_ACORN, PROD_ACORN_MFM },
	{ 0xffff, 0xffff },
};

static struct ecard_driver mfm_driver = {
	.probe		= mfm_probe,
	.remove		= __devexit(mfm_remove),
	.id_table	= mfm_cids,
	.drv = {
		.name	= "mfm",
	},
};

/*
 * Look for a MFM controller - first check the motherboard, then the podules
 * The podules have an extra interrupt enable that needs to be played with
 *
 * The HDC is accessed at MEDIUM IOC speeds.
 */
static int __init mfm_init (void)
{
	unsigned char irqmask;

	if (mfm_probecontroller(ONBOARD_MFM_ADDRESS)) {
		mfm_addr	= ONBOARD_MFM_ADDRESS;
		mfm_IRQPollLoc	= IOC_IRQSTATB;
		mfm_irqenable	= 0;
		mfm_irq		= IRQ_HARDDISK;
		return mfm_do_init(0x08);	/* IL3 pin */
	} else {
		return ecard_register_driver(&mfm_driver);
	}
}

static void __exit mfm_exit(void)
{
	if (mfm_addr == ONBOARD_MFM_ADDRESS)
		mfm_do_exit();
	else
		ecard_unregister_driver(&mfm_driver);
}

module_init(mfm_init)
module_exit(mfm_exit)
MODULE_LICENSE("GPL");