patch-2.3.99-pre1 linux/drivers/ide/ide-probe.c

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diff -u --recursive --new-file v2.3.51/linux/drivers/ide/ide-probe.c linux/drivers/ide/ide-probe.c
@@ -0,0 +1,929 @@
+/*
+ *  linux/drivers/block/ide-probe.c	Version 1.05	July 3, 1999
+ *
+ *  Copyright (C) 1994-1998  Linus Torvalds & authors (see below)
+ */
+
+/*
+ *  Mostly written by Mark Lord <mlord@pobox.com>
+ *                and Gadi Oxman <gadio@netvision.net.il>
+ *
+ *  See linux/MAINTAINERS for address of current maintainer.
+ *
+ * This is the IDE probe module, as evolved from hd.c and ide.c.
+ *
+ * Version 1.00		move drive probing code from ide.c to ide-probe.c
+ * Version 1.01		fix compilation problem for m68k
+ * Version 1.02		increase WAIT_PIDENTIFY to avoid CD-ROM locking at boot
+ *			 by Andrea Arcangeli
+ * Version 1.03		fix for (hwif->chipset == ide_4drives)
+ * Version 1.04		fixed buggy treatments of known flash memory cards
+ *
+ * Version 1.05		fix for (hwif->chipset == ide_pdc4030)
+ *			added ide6/7/8/9
+ *			allowed for secondary flash card to be detectable
+ *			 with new flag : drive->ata_flash : 1;
+ */
+
+#undef REALLY_SLOW_IO		/* most systems can safely undef this */
+
+#include <linux/config.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+#include <linux/timer.h>
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/major.h>
+#include <linux/errno.h>
+#include <linux/genhd.h>
+#include <linux/malloc.h>
+#include <linux/delay.h>
+#include <linux/ide.h>
+
+#include <asm/byteorder.h>
+#include <asm/irq.h>
+#include <asm/uaccess.h>
+#include <asm/io.h>
+
+static inline void do_identify (ide_drive_t *drive, byte cmd)
+{
+	int bswap = 1;
+	struct hd_driveid *id;
+
+	id = drive->id = kmalloc (SECTOR_WORDS*4, GFP_ATOMIC);	/* called with interrupts disabled! */
+	ide_input_data(drive, id, SECTOR_WORDS);		/* read 512 bytes of id info */
+	ide__sti();	/* local CPU only */
+	ide_fix_driveid(id);
+	if (!drive->forced_lun)
+		drive->last_lun = id->last_lun & 0x7;
+#if defined (CONFIG_SCSI_EATA_DMA) || defined (CONFIG_SCSI_EATA_PIO) || defined (CONFIG_SCSI_EATA)
+	/*
+	 * EATA SCSI controllers do a hardware ATA emulation:
+	 * Ignore them if there is a driver for them available.
+	 */
+	if ((id->model[0] == 'P' && id->model[1] == 'M')
+	 || (id->model[0] == 'S' && id->model[1] == 'K')) {
+		printk("%s: EATA SCSI HBA %.10s\n", drive->name, id->model);
+		drive->present = 0;
+		return;
+	}
+#endif /* CONFIG_SCSI_EATA_DMA || CONFIG_SCSI_EATA_PIO */
+
+	/*
+	 *  WIN_IDENTIFY returns little-endian info,
+	 *  WIN_PIDENTIFY *usually* returns little-endian info.
+	 */
+	if (cmd == WIN_PIDENTIFY) {
+		if ((id->model[0] == 'N' && id->model[1] == 'E') /* NEC */
+		 || (id->model[0] == 'F' && id->model[1] == 'X') /* Mitsumi */
+		 || (id->model[0] == 'P' && id->model[1] == 'i'))/* Pioneer */
+			bswap ^= 1;	/* Vertos drives may still be weird */
+	}
+	ide_fixstring (id->model,     sizeof(id->model),     bswap);
+	ide_fixstring (id->fw_rev,    sizeof(id->fw_rev),    bswap);
+	ide_fixstring (id->serial_no, sizeof(id->serial_no), bswap);
+
+	if (strstr(id->model, "E X A B Y T E N E S T"))
+		return;
+
+	id->model[sizeof(id->model)-1] = '\0';	/* we depend on this a lot! */
+	printk("%s: %s, ", drive->name, id->model);
+	drive->present = 1;
+
+	/*
+	 * Check for an ATAPI device
+	 */
+	if (cmd == WIN_PIDENTIFY) {
+		byte type = (id->config >> 8) & 0x1f;
+		printk("ATAPI ");
+#ifdef CONFIG_BLK_DEV_PDC4030
+		if (HWIF(drive)->channel == 1 && HWIF(drive)->chipset == ide_pdc4030) {
+			printk(" -- not supported on 2nd Promise port\n");
+			drive->present = 0;
+			return;
+		}
+#endif /* CONFIG_BLK_DEV_PDC4030 */
+		switch (type) {
+			case ide_floppy:
+				if (!strstr(id->model, "CD-ROM")) {
+					if (!strstr(id->model, "oppy") && !strstr(id->model, "poyp") && !strstr(id->model, "ZIP"))
+						printk("cdrom or floppy?, assuming ");
+					if (drive->media != ide_cdrom) {
+						printk ("FLOPPY");
+						break;
+					}
+				}
+				type = ide_cdrom;	/* Early cdrom models used zero */
+			case ide_cdrom:
+				drive->removable = 1;
+#ifdef CONFIG_PPC
+				/* kludge for Apple PowerBook internal zip */
+				if (!strstr(id->model, "CD-ROM") && strstr(id->model, "ZIP")) {
+					printk ("FLOPPY");
+					type = ide_floppy;
+					break;
+				}
+#endif
+				printk ("CDROM");
+				break;
+			case ide_tape:
+				printk ("TAPE");
+				break;
+			case ide_optical:
+				printk ("OPTICAL");
+				drive->removable = 1;
+				break;
+			default:
+				printk("UNKNOWN (type %d)", type);
+				break;
+		}
+		printk (" drive\n");
+		drive->media = type;
+		return;
+	}
+
+	/*
+	 * Not an ATAPI device: looks like a "regular" hard disk
+	 */
+	if (id->config & (1<<7))
+		drive->removable = 1;
+	/*
+	 * Prevent long system lockup probing later for non-existant
+	 * slave drive if the hwif is actually a flash memory card of some variety:
+	 */
+	if (drive_is_flashcard(drive)) {
+		ide_drive_t *mate = &HWIF(drive)->drives[1^drive->select.b.unit];
+		if (!mate->ata_flash) {
+			mate->present = 0;
+			mate->noprobe = 1;
+		}
+	}
+	drive->media = ide_disk;
+	printk("ATA DISK drive\n");
+	return;
+}
+
+/*
+ * try_to_identify() sends an ATA(PI) IDENTIFY request to a drive
+ * and waits for a response.  It also monitors irqs while this is
+ * happening, in hope of automatically determining which one is
+ * being used by the interface.
+ *
+ * Returns:	0  device was identified
+ *		1  device timed-out (no response to identify request)
+ *		2  device aborted the command (refused to identify itself)
+ */
+static int try_to_identify (ide_drive_t *drive, byte cmd)
+{
+	int rc;
+	ide_ioreg_t hd_status;
+	unsigned long timeout;
+	unsigned long irqs = 0;
+	byte s, a;
+
+	if (IDE_CONTROL_REG) {
+		if (!HWIF(drive)->irq) {		/* already got an IRQ? */
+			probe_irq_off(probe_irq_on());	/* clear dangling irqs */
+			irqs = probe_irq_on();		/* start monitoring irqs */
+			OUT_BYTE(drive->ctl,IDE_CONTROL_REG);	/* enable device irq */
+		}
+
+		ide_delay_50ms();				/* take a deep breath */
+		a = IN_BYTE(IDE_ALTSTATUS_REG);
+		s = IN_BYTE(IDE_STATUS_REG);
+		if ((a ^ s) & ~INDEX_STAT) {
+			printk("%s: probing with STATUS(0x%02x) instead of ALTSTATUS(0x%02x)\n", drive->name, s, a);
+			hd_status = IDE_STATUS_REG;	/* ancient Seagate drives, broken interfaces */
+		} else {
+			hd_status = IDE_ALTSTATUS_REG;	/* use non-intrusive polling */
+		}
+	} else {
+		ide_delay_50ms();
+		hd_status = IDE_STATUS_REG;
+	}
+
+#if CONFIG_BLK_DEV_PDC4030
+	if (HWIF(drive)->chipset == ide_pdc4030) {
+		/* DC4030 hosted drives need their own identify... */
+		extern int pdc4030_identify(ide_drive_t *);
+		if (pdc4030_identify(drive)) {
+			if (irqs)
+				(void) probe_irq_off(irqs);
+			return 1;
+		}
+	} else
+#endif /* CONFIG_BLK_DEV_PDC4030 */
+		OUT_BYTE(cmd,IDE_COMMAND_REG);		/* ask drive for ID */
+	timeout = ((cmd == WIN_IDENTIFY) ? WAIT_WORSTCASE : WAIT_PIDENTIFY) / 2;
+	timeout += jiffies;
+	do {
+		if (0 < (signed long)(jiffies - timeout)) {
+			if (irqs)
+				(void) probe_irq_off(irqs);
+			return 1;	/* drive timed-out */
+		}
+		ide_delay_50ms();		/* give drive a breather */
+	} while (IN_BYTE(hd_status) & BUSY_STAT);
+
+	ide_delay_50ms();		/* wait for IRQ and DRQ_STAT */
+	if (OK_STAT(GET_STAT(),DRQ_STAT,BAD_R_STAT)) {
+		unsigned long flags;
+		__save_flags(flags);	/* local CPU only */
+		__cli();		/* local CPU only; some systems need this */
+		do_identify(drive, cmd); /* drive returned ID */
+		rc = 0;			/* drive responded with ID */
+		(void) GET_STAT();	/* clear drive IRQ */
+		__restore_flags(flags);	/* local CPU only */
+	} else
+		rc = 2;			/* drive refused ID */
+	if (IDE_CONTROL_REG && !HWIF(drive)->irq) {
+		irqs = probe_irq_off(irqs);	/* get our irq number */
+		if (irqs > 0) {
+			HWIF(drive)->irq = irqs; /* save it for later */
+			irqs = probe_irq_on();
+			OUT_BYTE(drive->ctl|2,IDE_CONTROL_REG); /* mask device irq */
+			udelay(5);
+			(void) probe_irq_off(irqs);
+			(void) probe_irq_off(probe_irq_on()); /* clear self-inflicted irq */
+			(void) GET_STAT();	/* clear drive IRQ */
+
+		} else {	/* Mmmm.. multiple IRQs.. don't know which was ours */
+			printk("%s: IRQ probe failed (%ld)\n", drive->name, irqs);
+#ifdef CONFIG_BLK_DEV_CMD640
+#ifdef CMD640_DUMP_REGS
+			if (HWIF(drive)->chipset == ide_cmd640) {
+				printk("%s: Hmmm.. probably a driver problem.\n", drive->name);
+				CMD640_DUMP_REGS;
+			}
+#endif /* CMD640_DUMP_REGS */
+#endif /* CONFIG_BLK_DEV_CMD640 */
+		}
+	}
+	return rc;
+}
+
+/*
+ * do_probe() has the difficult job of finding a drive if it exists,
+ * without getting hung up if it doesn't exist, without trampling on
+ * ethernet cards, and without leaving any IRQs dangling to haunt us later.
+ *
+ * If a drive is "known" to exist (from CMOS or kernel parameters),
+ * but does not respond right away, the probe will "hang in there"
+ * for the maximum wait time (about 30 seconds), otherwise it will
+ * exit much more quickly.
+ *
+ * Returns:	0  device was identified
+ *		1  device timed-out (no response to identify request)
+ *		2  device aborted the command (refused to identify itself)
+ *		3  bad status from device (possible for ATAPI drives)
+ *		4  probe was not attempted because failure was obvious
+ */
+static int do_probe (ide_drive_t *drive, byte cmd)
+{
+	int rc;
+	ide_hwif_t *hwif = HWIF(drive);
+	if (drive->present) {	/* avoid waiting for inappropriate probes */
+		if ((drive->media != ide_disk) && (cmd == WIN_IDENTIFY))
+			return 4;
+	}
+#ifdef DEBUG
+	printk("probing for %s: present=%d, media=%d, probetype=%s\n",
+		drive->name, drive->present, drive->media,
+		(cmd == WIN_IDENTIFY) ? "ATA" : "ATAPI");
+#endif
+	ide_delay_50ms();	/* needed for some systems (e.g. crw9624 as drive0 with disk as slave) */
+	SELECT_DRIVE(hwif,drive);
+	ide_delay_50ms();
+	if (IN_BYTE(IDE_SELECT_REG) != drive->select.all && !drive->present) {
+		if (drive->select.b.unit != 0) {
+			SELECT_DRIVE(hwif,&hwif->drives[0]);	/* exit with drive0 selected */
+			ide_delay_50ms();		/* allow BUSY_STAT to assert & clear */
+		}
+		return 3;    /* no i/f present: mmm.. this should be a 4 -ml */
+	}
+
+	if (OK_STAT(GET_STAT(),READY_STAT,BUSY_STAT)
+	 || drive->present || cmd == WIN_PIDENTIFY)
+	{
+		if ((rc = try_to_identify(drive,cmd)))   /* send cmd and wait */
+			rc = try_to_identify(drive,cmd); /* failed: try again */
+		if (rc == 1 && cmd == WIN_PIDENTIFY && drive->autotune != 2) {
+			unsigned long timeout;
+			printk("%s: no response (status = 0x%02x), resetting drive\n", drive->name, GET_STAT());
+			ide_delay_50ms();
+			OUT_BYTE (drive->select.all, IDE_SELECT_REG);
+			ide_delay_50ms();
+			OUT_BYTE(WIN_SRST, IDE_COMMAND_REG);
+			timeout = jiffies;
+			while ((GET_STAT() & BUSY_STAT) && time_before(jiffies, timeout + WAIT_WORSTCASE))
+				ide_delay_50ms();
+			rc = try_to_identify(drive, cmd);
+		}
+		if (rc == 1)
+			printk("%s: no response (status = 0x%02x)\n", drive->name, GET_STAT());
+		(void) GET_STAT();		/* ensure drive irq is clear */
+	} else {
+		rc = 3;				/* not present or maybe ATAPI */
+	}
+	if (drive->select.b.unit != 0) {
+		SELECT_DRIVE(hwif,&hwif->drives[0]);	/* exit with drive0 selected */
+		ide_delay_50ms();
+		(void) GET_STAT();		/* ensure drive irq is clear */
+	}
+	return rc;
+}
+
+/*
+ *
+ */
+static void enable_nest (ide_drive_t *drive)
+{
+	unsigned long timeout;
+
+	printk("%s: enabling %s -- ", HWIF(drive)->name, drive->id->model);
+	SELECT_DRIVE(HWIF(drive), drive);
+	ide_delay_50ms();
+	OUT_BYTE(EXABYTE_ENABLE_NEST, IDE_COMMAND_REG);
+	timeout = jiffies + WAIT_WORSTCASE;
+	do {
+		if (jiffies > timeout) {
+			printk("failed (timeout)\n");
+			return;
+		}
+		ide_delay_50ms();
+	} while (GET_STAT() & BUSY_STAT);
+	ide_delay_50ms();
+	if (!OK_STAT(GET_STAT(), 0, BAD_STAT))
+		printk("failed (status = 0x%02x)\n", GET_STAT());
+	else
+		printk("success\n");
+	if (do_probe(drive, WIN_IDENTIFY) >= 2) {	/* if !(success||timed-out) */
+		(void) do_probe(drive, WIN_PIDENTIFY);	/* look for ATAPI device */
+	}
+}
+
+/*
+ * probe_for_drive() tests for existence of a given drive using do_probe().
+ *
+ * Returns:	0  no device was found
+ *		1  device was found (note: drive->present might still be 0)
+ */
+static inline byte probe_for_drive (ide_drive_t *drive)
+{
+	if (drive->noprobe)			/* skip probing? */
+		return drive->present;
+	if (do_probe(drive, WIN_IDENTIFY) >= 2) { /* if !(success||timed-out) */
+		(void) do_probe(drive, WIN_PIDENTIFY); /* look for ATAPI device */
+	}
+	if (drive->id && strstr(drive->id->model, "E X A B Y T E N E S T"))
+		enable_nest(drive);
+	if (!drive->present)
+		return 0;			/* drive not found */
+	if (drive->id == NULL) {		/* identification failed? */
+		if (drive->media == ide_disk) {
+			printk ("%s: non-IDE drive, CHS=%d/%d/%d\n",
+			 drive->name, drive->cyl, drive->head, drive->sect);
+		} else if (drive->media == ide_cdrom) {
+			printk("%s: ATAPI cdrom (?)\n", drive->name);
+		} else {
+			drive->present = 0;	/* nuke it */
+		}
+	}
+	return 1;	/* drive was found */
+}
+
+/*
+ * Calculate the region that this interface occupies,
+ * handling interfaces where the registers may not be
+ * ordered sanely.  We deal with the CONTROL register
+ * separately.
+ */
+static int hwif_check_regions (ide_hwif_t *hwif)
+{
+	int region_errors = 0;
+
+	hwif->straight8 = 0;
+	region_errors  = ide_check_region(hwif->io_ports[IDE_DATA_OFFSET], 1);
+	region_errors += ide_check_region(hwif->io_ports[IDE_ERROR_OFFSET], 1);
+	region_errors += ide_check_region(hwif->io_ports[IDE_NSECTOR_OFFSET], 1);
+	region_errors += ide_check_region(hwif->io_ports[IDE_SECTOR_OFFSET], 1);
+	region_errors += ide_check_region(hwif->io_ports[IDE_LCYL_OFFSET], 1);
+	region_errors += ide_check_region(hwif->io_ports[IDE_HCYL_OFFSET], 1);
+	region_errors += ide_check_region(hwif->io_ports[IDE_SELECT_OFFSET], 1);
+	region_errors += ide_check_region(hwif->io_ports[IDE_STATUS_OFFSET], 1);
+
+	if (hwif->io_ports[IDE_CONTROL_OFFSET])
+		region_errors += ide_check_region(hwif->io_ports[IDE_CONTROL_OFFSET], 1);
+
+	if (hwif->io_ports[IDE_IRQ_OFFSET])
+		region_errors += ide_check_region(hwif->io_ports[IDE_IRQ_OFFSET], 1);
+
+	/*
+	 * If any errors are return, we drop the hwif interface.
+	 */
+	return(region_errors);
+}
+
+static void hwif_register (ide_hwif_t *hwif)
+{
+	if ((hwif->io_ports[IDE_DATA_OFFSET] | 7) ==
+	    (hwif->io_ports[IDE_STATUS_OFFSET])) {
+		ide_request_region(hwif->io_ports[IDE_DATA_OFFSET], 8, hwif->name);
+		hwif->straight8 = 1;
+		goto jump_straight8;
+	}
+
+	if (hwif->io_ports[IDE_DATA_OFFSET])
+		ide_request_region(hwif->io_ports[IDE_DATA_OFFSET], 1, hwif->name);
+	if (hwif->io_ports[IDE_ERROR_OFFSET])
+		ide_request_region(hwif->io_ports[IDE_ERROR_OFFSET], 1, hwif->name);
+	if (hwif->io_ports[IDE_NSECTOR_OFFSET])
+		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 (hwif->io_ports[IDE_IRQ_OFFSET])
+		ide_request_region(hwif->io_ports[IDE_IRQ_OFFSET], 1, hwif->name);
+}
+
+/*
+ * 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;
+	if (hwif->io_ports[IDE_DATA_OFFSET] == HD_DATA) {
+		extern void probe_cmos_for_drives(ide_hwif_t *);
+
+		probe_cmos_for_drives (hwif);
+	}
+
+	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 */
+
+/*
+ * 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;
+	ide_hwif_t *match = NULL;
+
+	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;
+	} else {
+		hwgroup = kmalloc(sizeof(ide_hwgroup_t), GFP_KERNEL);
+		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 = (hwif->chipset == ide_pci) ? SA_SHIRQ : SA_INTERRUPT;
+#else /* !CONFIG_IDEPCI_SHARE_IRQ */
+		int sa = (hwif->chipset == ide_pci) ? 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;
+	}
+	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, **gdp;
+	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 : MAX_SECTORS);
+#else
+		*max_sect++ = MAX_SECTORS;
+#endif
+		*max_ra++ = 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);
+
+	for (gdp = &gendisk_head; *gdp; gdp = &((*gdp)->next)) ;
+	hwif->gd = *gdp = gd;			/* link onto tail of list */
+
+	for (unit = 0; unit < units; ++unit) {
+		if (hwif->drives[unit].present) {
+			char name[64];
+
+			ide_add_generic_settings(hwif->drives + unit);
+			sprintf (name, "host%d/bus%d/target%d/lun%d",
+				 (hwif->channel && hwif->mate) ? hwif->mate->index : hwif->index,
+				 hwif->channel, unit, 0);
+			hwif->drives[unit].de =
+				devfs_mk_dir (ide_devfs_handle, name, 0, NULL);
+		}
+	}
+}
+
+static int hwif_init (ide_hwif_t *hwif)
+{
+	ide_drive_t *drive;
+	void (*rfn)(request_queue_t *);
+	
+	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 */
+	switch (hwif->major) {
+	case IDE0_MAJOR: rfn = &do_ide0_request; break;
+#if MAX_HWIFS > 1
+	case IDE1_MAJOR: rfn = &do_ide1_request; break;
+#endif
+#if MAX_HWIFS > 2
+	case IDE2_MAJOR: rfn = &do_ide2_request; break;
+#endif
+#if MAX_HWIFS > 3
+	case IDE3_MAJOR: rfn = &do_ide3_request; break;
+#endif
+#if MAX_HWIFS > 4
+	case IDE4_MAJOR: rfn = &do_ide4_request; break;
+#endif
+#if MAX_HWIFS > 5
+	case IDE5_MAJOR: rfn = &do_ide5_request; break;
+#endif
+#if MAX_HWIFS > 6
+	case IDE6_MAJOR: rfn = &do_ide6_request; break;
+#endif
+#if MAX_HWIFS > 7
+	case IDE7_MAJOR: rfn = &do_ide7_request; break;
+#endif
+#if MAX_HWIFS > 8
+	case IDE8_MAJOR: rfn = &do_ide8_request; break;
+#endif
+#if MAX_HWIFS > 9
+	case IDE9_MAJOR: rfn = &do_ide9_request; break;
+#endif
+	default:
+		printk("%s: request_fn NOT DEFINED\n", hwif->name);
+		return (hwif->present = 0);
+	}
+	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 */
+
+	/*
+	 * FIXME(eric) - This needs to be tested.  I *think* that this
+	 * is correct.   Also, I believe that there is no longer any
+	 * reason to have multiple functions (do_ide[0-7]_request)
+	 * functions - the queuedata field could be used to indicate
+	 * the correct hardware group - either this, or we could add
+	 * a new field to request_queue_t to hold this information.
+	 */
+	drive = &hwif->drives[0];
+	blk_init_queue(&drive->queue, rfn);
+
+	drive = &hwif->drives[1];
+	blk_init_queue(&drive->queue, rfn);
+
+#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;
+}
+#endif /* MODULE */

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TCL-scripts by Sam Shen (who was at: slshen@lbl.gov)