ide-probe.c

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		ide_request_region(hwif->io_ports[IDE_NSECTOR_OFFSET], 1, hwif->name);
	if (hwif->io_ports[IDE_SECTOR_OFFSET])
		ide_request_region(hwif->io_ports[IDE_SECTOR_OFFSET], 1, hwif->name);
	if (hwif->io_ports[IDE_LCYL_OFFSET])
		ide_request_region(hwif->io_ports[IDE_LCYL_OFFSET], 1, hwif->name);
	if (hwif->io_ports[IDE_HCYL_OFFSET])
		ide_request_region(hwif->io_ports[IDE_HCYL_OFFSET], 1, hwif->name);
	if (hwif->io_ports[IDE_SELECT_OFFSET])
		ide_request_region(hwif->io_ports[IDE_SELECT_OFFSET], 1, hwif->name);
	if (hwif->io_ports[IDE_STATUS_OFFSET])
		ide_request_region(hwif->io_ports[IDE_STATUS_OFFSET], 1, hwif->name);

jump_straight8:
	if (hwif->io_ports[IDE_CONTROL_OFFSET])
		ide_request_region(hwif->io_ports[IDE_CONTROL_OFFSET], 1, hwif->name);
#if defined(CONFIG_AMIGA) || defined(CONFIG_MAC)
	if (hwif->io_ports[IDE_IRQ_OFFSET])
		ide_request_region(hwif->io_ports[IDE_IRQ_OFFSET], 1, hwif->name);
#endif /* (CONFIG_AMIGA) || (CONFIG_MAC) */
}

/*
 * This routine only knows how to look for drive units 0 and 1
 * on an interface, so any setting of MAX_DRIVES > 2 won't work here.
 */
static void probe_hwif (ide_hwif_t *hwif)
{
	unsigned int unit;
	unsigned long flags;

	if (hwif->noprobe)
		return;
#ifdef CONFIG_BLK_DEV_IDE
	if (hwif->io_ports[IDE_DATA_OFFSET] == HD_DATA) {
		extern void probe_cmos_for_drives(ide_hwif_t *);

		probe_cmos_for_drives (hwif);
	}
#endif

	if ((hwif->chipset != ide_4drives || !hwif->mate->present) &&
#if CONFIG_BLK_DEV_PDC4030
	    (hwif->chipset != ide_pdc4030 || hwif->channel == 0) &&
#endif /* CONFIG_BLK_DEV_PDC4030 */
	    (hwif_check_regions(hwif))) {
		int msgout = 0;
		for (unit = 0; unit < MAX_DRIVES; ++unit) {
			ide_drive_t *drive = &hwif->drives[unit];
			if (drive->present) {
				drive->present = 0;
				printk("%s: ERROR, PORTS ALREADY IN USE\n", drive->name);
				msgout = 1;
			}
		}
		if (!msgout)
			printk("%s: ports already in use, skipping probe\n", hwif->name);
		return;	
	}

	__save_flags(flags);	/* local CPU only */
	__sti();		/* local CPU only; needed for jiffies and irq probing */
	/*
	 * Second drive should only exist if first drive was found,
	 * but a lot of cdrom drives are configured as single slaves.
	 */
	for (unit = 0; unit < MAX_DRIVES; ++unit) {
		ide_drive_t *drive = &hwif->drives[unit];
		(void) probe_for_drive (drive);
		if (drive->present && !hwif->present) {
			hwif->present = 1;
			if (hwif->chipset != ide_4drives || !hwif->mate->present) {
				hwif_register(hwif);
			}
		}
	}
	if (hwif->io_ports[IDE_CONTROL_OFFSET] && hwif->reset) {
		unsigned long timeout = jiffies + WAIT_WORSTCASE;
		byte stat;

		printk("%s: reset\n", hwif->name);
		OUT_BYTE(12, hwif->io_ports[IDE_CONTROL_OFFSET]);
		udelay(10);
		OUT_BYTE(8, hwif->io_ports[IDE_CONTROL_OFFSET]);
		do {
			ide_delay_50ms();
			stat = IN_BYTE(hwif->io_ports[IDE_STATUS_OFFSET]);
		} while ((stat & BUSY_STAT) && 0 < (signed long)(timeout - jiffies));

	}
	__restore_flags(flags);	/* local CPU only */
	for (unit = 0; unit < MAX_DRIVES; ++unit) {
		ide_drive_t *drive = &hwif->drives[unit];
		if (drive->present) {
			ide_tuneproc_t *tuneproc = HWIF(drive)->tuneproc;
			if (tuneproc != NULL && drive->autotune == 1)
				tuneproc(drive, 255);	/* auto-tune PIO mode */
		}
	}
}

#if MAX_HWIFS > 1
/*
 * save_match() is used to simplify logic in init_irq() below.
 *
 * A loophole here is that we may not know about a particular
 * hwif's irq until after that hwif is actually probed/initialized..
 * This could be a problem for the case where an hwif is on a
 * dual interface that requires serialization (eg. cmd640) and another
 * hwif using one of the same irqs is initialized beforehand.
 *
 * This routine detects and reports such situations, but does not fix them.
 */
static void save_match (ide_hwif_t *hwif, ide_hwif_t *new, ide_hwif_t **match)
{
	ide_hwif_t *m = *match;

	if (m && m->hwgroup && m->hwgroup != new->hwgroup) {
		if (!new->hwgroup)
			return;
		printk("%s: potential irq problem with %s and %s\n", hwif->name, new->name, m->name);
	}
	if (!m || m->irq != hwif->irq) /* don't undo a prior perfect match */
		*match = new;
}
#endif /* MAX_HWIFS > 1 */

/*
 * init request queue
 */
static void ide_init_queue(ide_drive_t *drive)
{
	request_queue_t *q = &drive->queue;

	q->queuedata = HWGROUP(drive);
	blk_init_queue(q, do_ide_request);
}

/*
 * This routine sets up the irq for an ide interface, and creates a new
 * hwgroup for the irq/hwif if none was previously assigned.
 *
 * Much of the code is for correctly detecting/handling irq sharing
 * and irq serialization situations.  This is somewhat complex because
 * it handles static as well as dynamic (PCMCIA) IDE interfaces.
 *
 * The SA_INTERRUPT in sa_flags means ide_intr() is always entered with
 * interrupts completely disabled.  This can be bad for interrupt latency,
 * but anything else has led to problems on some machines.  We re-enable
 * interrupts as much as we can safely do in most places.
 */
static int init_irq (ide_hwif_t *hwif)
{
	unsigned long flags;
	unsigned int index;
	ide_hwgroup_t *hwgroup, *new_hwgroup;
	ide_hwif_t *match = NULL;

	
	/* Allocate the buffer and potentially sleep first */
	
	new_hwgroup = kmalloc(sizeof(ide_hwgroup_t),GFP_KERNEL);
	
	save_flags(flags);	/* all CPUs */
	cli();			/* all CPUs */

	hwif->hwgroup = NULL;
#if MAX_HWIFS > 1
	/*
	 * Group up with any other hwifs that share our irq(s).
	 */
	for (index = 0; index < MAX_HWIFS; index++) {
		ide_hwif_t *h = &ide_hwifs[index];
		if (h->hwgroup) {  /* scan only initialized hwif's */
			if (hwif->irq == h->irq) {
				hwif->sharing_irq = h->sharing_irq = 1;
				if (hwif->chipset != ide_pci || h->chipset != ide_pci) {
					save_match(hwif, h, &match);
				}
			}
			if (hwif->serialized) {
				if (hwif->mate && hwif->mate->irq == h->irq)
					save_match(hwif, h, &match);
			}
			if (h->serialized) {
				if (h->mate && hwif->irq == h->mate->irq)
					save_match(hwif, h, &match);
			}
		}
	}
#endif /* MAX_HWIFS > 1 */
	/*
	 * If we are still without a hwgroup, then form a new one
	 */
	if (match) {
		hwgroup = match->hwgroup;
		if(new_hwgroup)
			kfree(new_hwgroup);
	} else {
		hwgroup = new_hwgroup;
		if (!hwgroup) {
			restore_flags(flags);	/* all CPUs */
			return 1;
		}
		memset(hwgroup, 0, sizeof(ide_hwgroup_t));
		hwgroup->hwif     = hwif->next = hwif;
		hwgroup->rq       = NULL;
		hwgroup->handler  = NULL;
		hwgroup->drive    = NULL;
		hwgroup->busy     = 0;
		init_timer(&hwgroup->timer);
		hwgroup->timer.function = &ide_timer_expiry;
		hwgroup->timer.data = (unsigned long) hwgroup;
	}

	/*
	 * Allocate the irq, if not already obtained for another hwif
	 */
	if (!match || match->irq != hwif->irq) {
#ifdef CONFIG_IDEPCI_SHARE_IRQ
		int sa = IDE_CHIPSET_IS_PCI(hwif->chipset) ? SA_SHIRQ : SA_INTERRUPT;
#else /* !CONFIG_IDEPCI_SHARE_IRQ */
		int sa = IDE_CHIPSET_IS_PCI(hwif->chipset) ? SA_INTERRUPT|SA_SHIRQ : SA_INTERRUPT;
#endif /* CONFIG_IDEPCI_SHARE_IRQ */
		if (ide_request_irq(hwif->irq, &ide_intr, sa, hwif->name, hwgroup)) {
			if (!match)
				kfree(hwgroup);
			restore_flags(flags);	/* all CPUs */
			return 1;
		}
	}

	/*
	 * Everything is okay, so link us into the hwgroup
	 */
	hwif->hwgroup = hwgroup;
	hwif->next = hwgroup->hwif->next;
	hwgroup->hwif->next = hwif;

	for (index = 0; index < MAX_DRIVES; ++index) {
		ide_drive_t *drive = &hwif->drives[index];
		if (!drive->present)
			continue;
		if (!hwgroup->drive)
			hwgroup->drive = drive;
		drive->next = hwgroup->drive->next;
		hwgroup->drive->next = drive;
		ide_init_queue(drive);
	}
	if (!hwgroup->hwif) {
		hwgroup->hwif = HWIF(hwgroup->drive);
#ifdef DEBUG
		printk("%s : Adding missed hwif to hwgroup!!\n", hwif->name);
#endif
	}
	restore_flags(flags);	/* all CPUs; safe now that hwif->hwgroup is set up */

#if !defined(__mc68000__) && !defined(CONFIG_APUS) && !defined(__sparc__)
	printk("%s at 0x%03x-0x%03x,0x%03x on irq %d", hwif->name,
		hwif->io_ports[IDE_DATA_OFFSET],
		hwif->io_ports[IDE_DATA_OFFSET]+7,
		hwif->io_ports[IDE_CONTROL_OFFSET], hwif->irq);
#elif defined(__sparc__)
	printk("%s at 0x%03lx-0x%03lx,0x%03lx on irq %s", hwif->name,
		hwif->io_ports[IDE_DATA_OFFSET],
		hwif->io_ports[IDE_DATA_OFFSET]+7,
		hwif->io_ports[IDE_CONTROL_OFFSET], __irq_itoa(hwif->irq));
#else
	printk("%s at %p on irq 0x%08x", hwif->name,
		hwif->io_ports[IDE_DATA_OFFSET], hwif->irq);
#endif /* __mc68000__ && CONFIG_APUS */
	if (match)
		printk(" (%sed with %s)",
			hwif->sharing_irq ? "shar" : "serializ", match->name);
	printk("\n");
	return 0;
}

/*
 * init_gendisk() (as opposed to ide_geninit) is called for each major device,
 * after probing for drives, to allocate partition tables and other data
 * structures needed for the routines in genhd.c.  ide_geninit() gets called
 * somewhat later, during the partition check.
 */
static void init_gendisk (ide_hwif_t *hwif)
{
	struct gendisk *gd;
	unsigned int unit, units, minors;
	int *bs, *max_sect, *max_ra;
	extern devfs_handle_t ide_devfs_handle;

	/* figure out maximum drive number on the interface */
	for (units = MAX_DRIVES; units > 0; --units) {
		if (hwif->drives[units-1].present)
			break;
	}
	minors    = units * (1<<PARTN_BITS);
	gd        = kmalloc (sizeof(struct gendisk), GFP_KERNEL);
	gd->sizes = kmalloc (minors * sizeof(int), GFP_KERNEL);
	gd->part  = kmalloc (minors * sizeof(struct hd_struct), GFP_KERNEL);
	bs        = kmalloc (minors*sizeof(int), GFP_KERNEL);
	max_sect  = kmalloc (minors*sizeof(int), GFP_KERNEL);
	max_ra    = kmalloc (minors*sizeof(int), GFP_KERNEL);

	memset(gd->part, 0, minors * sizeof(struct hd_struct));

	/* cdroms and msdos f/s are examples of non-1024 blocksizes */
	blksize_size[hwif->major] = bs;
	max_sectors[hwif->major] = max_sect;
	max_readahead[hwif->major] = max_ra;
	for (unit = 0; unit < minors; ++unit) {
		*bs++ = BLOCK_SIZE;
#ifdef CONFIG_BLK_DEV_PDC4030
		*max_sect++ = ((hwif->chipset == ide_pdc4030) ? 127 : 255);
#else
		/* IDE can do up to 128K per request. */
		*max_sect++ = 255;
#endif
		*max_ra++ = vm_max_readahead;
	}

	for (unit = 0; unit < units; ++unit)
		hwif->drives[unit].part = &gd->part[unit << PARTN_BITS];

	gd->major	= hwif->major;		/* our major device number */
	gd->major_name	= IDE_MAJOR_NAME;	/* treated special in genhd.c */
	gd->minor_shift	= PARTN_BITS;		/* num bits for partitions */
	gd->max_p	= 1<<PARTN_BITS;	/* 1 + max partitions / drive */
	gd->nr_real	= units;		/* current num real drives */
	gd->real_devices= hwif;			/* ptr to internal data */
	gd->next	= NULL;			/* linked list of major devs */
	gd->fops        = ide_fops;             /* file operations */
	gd->de_arr	= kmalloc (sizeof *gd->de_arr * units, GFP_KERNEL);
	gd->flags	= kmalloc (sizeof *gd->flags * units, GFP_KERNEL);
	if (gd->de_arr)
		memset (gd->de_arr, 0, sizeof *gd->de_arr * units);
	if (gd->flags)
		memset (gd->flags, 0, sizeof *gd->flags * units);

	hwif->gd = gd;
	add_gendisk(gd);

	for (unit = 0; unit < units; ++unit) {
		if (hwif->drives[unit].present) {
			char name[64];

			ide_add_generic_settings(hwif->drives + unit);
			hwif->drives[unit].dn = ((hwif->channel ? 2 : 0) + unit);
			sprintf (name, "host%d/bus%d/target%d/lun%d",
				 (hwif->channel && hwif->mate) ? hwif->mate->index : hwif->index,
				 hwif->channel, unit, hwif->drives[unit].lun);
			hwif->drives[unit].de =
				devfs_mk_dir (ide_devfs_handle, name, NULL);
		}
	}
}

static int hwif_init (ide_hwif_t *hwif)
{
	if (!hwif->present)
		return 0;
	if (!hwif->irq) {
		if (!(hwif->irq = ide_default_irq(hwif->io_ports[IDE_DATA_OFFSET])))
		{
			printk("%s: DISABLED, NO IRQ\n", hwif->name);
			return (hwif->present = 0);
		}
	}
#ifdef CONFIG_BLK_DEV_HD
	if (hwif->irq == HD_IRQ && hwif->io_ports[IDE_DATA_OFFSET] != HD_DATA) {
		printk("%s: CANNOT SHARE IRQ WITH OLD HARDDISK DRIVER (hd.c)\n", hwif->name);
		return (hwif->present = 0);
	}
#endif /* CONFIG_BLK_DEV_HD */
	
	hwif->present = 0; /* we set it back to 1 if all is ok below */

	if (devfs_register_blkdev (hwif->major, hwif->name, ide_fops)) {
		printk("%s: UNABLE TO GET MAJOR NUMBER %d\n", hwif->name, hwif->major);
		return (hwif->present = 0);
	}

	if (init_irq(hwif)) {
		int i = hwif->irq;
		/*
		 *	It failed to initialise. Find the default IRQ for
		 *	this port and try that.
		 */
		if (!(hwif->irq = ide_default_irq(hwif->io_ports[IDE_DATA_OFFSET]))) {
			printk("%s: Disabled unable to get IRQ %d.\n", hwif->name, i);
			(void) unregister_blkdev (hwif->major, hwif->name);
			return (hwif->present = 0);
		}
		if (init_irq(hwif)) {
			printk("%s: probed IRQ %d and default IRQ %d failed.\n",
				hwif->name, i, hwif->irq);
			(void) unregister_blkdev (hwif->major, hwif->name);
			return (hwif->present = 0);
		}
		printk("%s: probed IRQ %d failed, using default.\n",
			hwif->name, hwif->irq);
	}

	init_gendisk(hwif);
	blk_dev[hwif->major].data = hwif;
	blk_dev[hwif->major].queue = ide_get_queue;
	read_ahead[hwif->major] = 8;	/* (4kB) */
	hwif->present = 1;	/* success */

#if (DEBUG_SPINLOCK > 0)
{
	static int done = 0;
	if (!done++)
		printk("io_request_lock is %p\n", &io_request_lock);    /* FIXME */
}
#endif
	return hwif->present;
}

int ideprobe_init (void);
static ide_module_t ideprobe_module = {
	IDE_PROBE_MODULE,
	ideprobe_init,
	NULL
};

int ideprobe_init (void)
{
	unsigned int index;
	int probe[MAX_HWIFS];
	
	MOD_INC_USE_COUNT;
	memset(probe, 0, MAX_HWIFS * sizeof(int));
	for (index = 0; index < MAX_HWIFS; ++index)
		probe[index] = !ide_hwifs[index].present;

	/*
	 * Probe for drives in the usual way.. CMOS/BIOS, then poke at ports
	 */
	for (index = 0; index < MAX_HWIFS; ++index)
		if (probe[index])
			probe_hwif(&ide_hwifs[index]);
	for (index = 0; index < MAX_HWIFS; ++index)
		if (probe[index])
			hwif_init(&ide_hwifs[index]);
	if (!ide_probe)
		ide_probe = &ideprobe_module;
	MOD_DEC_USE_COUNT;
	return 0;
}

#ifdef MODULE
int init_module (void)
{
	unsigned int index;
	
	for (index = 0; index < MAX_HWIFS; ++index)
		ide_unregister(index);
	ideprobe_init();
	create_proc_ide_interfaces();
	return 0;
}

void cleanup_module (void)
{
	ide_probe = NULL;
}
MODULE_LICENSE("GPL");
#endif /* MODULE */