ide-probe.c

linux 内核源代码

/*
 *  linux/drivers/ide/ide-probe.c	Version 1.11	Mar 05, 2003
 *
 *  Copyright (C) 1994-1998  Linus Torvalds & authors (see below)
 */

/*
 *  Mostly written by Mark Lord <[e-mail]>
 *                and Gadi Oxman <[e-mail]>
 *                and Andre Hedrick <[e-mail]>
 *
 *  See linux/MAINTAINERS for address of current maintainer.
 *
 * This is the IDE probe module, as evolved from hd.c and ide.c.
 *
 * -- increase WAIT_PIDENTIFY to avoid CD-ROM locking at boot
 *	 by Andrea Arcangeli
 */

#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/slab.h>
#include <linux/delay.h>
#include <linux/ide.h>
#include <linux/spinlock.h>
#include <linux/kmod.h>
#include <linux/pci.h>
#include <linux/scatterlist.h>

#include <asm/byteorder.h>
#include <asm/irq.h>
#include <asm/uaccess.h>
#include <asm/io.h>

/**
 *	generic_id		-	add a generic drive id
 *	@drive:	drive to make an ID block for
 *	
 *	Add a fake id field to the drive we are passed. This allows
 *	use to skip a ton of NULL checks (which people always miss) 
 *	and make drive properties unconditional outside of this file
 */
 
static void generic_id(ide_drive_t *drive)
{
	drive->id->cyls = drive->cyl;
	drive->id->heads = drive->head;
	drive->id->sectors = drive->sect;
	drive->id->cur_cyls = drive->cyl;
	drive->id->cur_heads = drive->head;
	drive->id->cur_sectors = drive->sect;
}

static void ide_disk_init_chs(ide_drive_t *drive)
{
	struct hd_driveid *id = drive->id;

	/* Extract geometry if we did not already have one for the drive */
	if (!drive->cyl || !drive->head || !drive->sect) {
		drive->cyl  = drive->bios_cyl  = id->cyls;
		drive->head = drive->bios_head = id->heads;
		drive->sect = drive->bios_sect = id->sectors;
	}

	/* Handle logical geometry translation by the drive */
	if ((id->field_valid & 1) && id->cur_cyls &&
	    id->cur_heads && (id->cur_heads <= 16) && id->cur_sectors) {
		drive->cyl  = id->cur_cyls;
		drive->head = id->cur_heads;
		drive->sect = id->cur_sectors;
	}

	/* Use physical geometry if what we have still makes no sense */
	if (drive->head > 16 && id->heads && id->heads <= 16) {
		drive->cyl  = id->cyls;
		drive->head = id->heads;
		drive->sect = id->sectors;
	}
}

static void ide_disk_init_mult_count(ide_drive_t *drive)
{
	struct hd_driveid *id = drive->id;

	drive->mult_count = 0;
	if (id->max_multsect) {
#ifdef CONFIG_IDEDISK_MULTI_MODE
		id->multsect = ((id->max_multsect/2) > 1) ? id->max_multsect : 0;
		id->multsect_valid = id->multsect ? 1 : 0;
		drive->mult_req = id->multsect_valid ? id->max_multsect : INITIAL_MULT_COUNT;
		drive->special.b.set_multmode = drive->mult_req ? 1 : 0;
#else	/* original, pre IDE-NFG, per request of AC */
		drive->mult_req = INITIAL_MULT_COUNT;
		if (drive->mult_req > id->max_multsect)
			drive->mult_req = id->max_multsect;
		if (drive->mult_req || ((id->multsect_valid & 1) && id->multsect))
			drive->special.b.set_multmode = 1;
#endif
	}
}

/**
 *	do_identify	-	identify a drive
 *	@drive: drive to identify 
 *	@cmd: command used
 *
 *	Called when we have issued a drive identify command to
 *	read and parse the results. This function is run with
 *	interrupts disabled. 
 */
 
static inline void do_identify (ide_drive_t *drive, u8 cmd)
{
	ide_hwif_t *hwif = HWIF(drive);
	int bswap = 1;
	struct hd_driveid *id;

	id = drive->id;
	/* read 512 bytes of id info */
	hwif->ata_input_data(drive, id, SECTOR_WORDS);

	drive->id_read = 1;
	local_irq_enable();
	ide_fix_driveid(id);

#if 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);
		goto err_misc;
	}
#endif /* CONFIG_SCSI_EATA || 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 */
			/* Vertos drives may still be weird */
			bswap ^= 1;	
	}
	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);

	/* we depend on this a lot! */
	id->model[sizeof(id->model)-1] = '\0';

	if (strstr(id->model, "E X A B Y T E N E S T"))
		goto err_misc;

	printk("%s: %s, ", drive->name, id->model);
	drive->present = 1;
	drive->dead = 0;

	/*
	 * Check for an ATAPI device
	 */
	if (cmd == WIN_PIDENTIFY) {
		u8 type = (id->config >> 8) & 0x1f;
		printk("ATAPI ");
		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");
						drive->removable = 1;
						break;
					}
				}
				/* Early cdrom models used zero */
				type = ide_cdrom;
			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 ("CD/DVD-ROM");
				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;
		/* an ATAPI device ignores DRDY */
		drive->ready_stat = 0;
		return;
	}

	/*
	 * Not an ATAPI device: looks like a "regular" hard disk
	 */

	/*
	 * 0x848a = CompactFlash device
	 * These are *not* removable in Linux definition of the term
	 */

	if ((id->config != 0x848a) && (id->config & (1<<7)))
		drive->removable = 1;

	drive->media = ide_disk;
	printk("%s DISK drive\n", (id->config == 0x848a) ? "CFA" : "ATA" );
	QUIRK_LIST(drive);
	return;

err_misc:
	kfree(id);
	drive->present = 0;
	return;
}

/**
 *	actual_try_to_identify	-	send ata/atapi identify
 *	@drive: drive to identify
 *	@cmd: command to use
 *
 *	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 actual_try_to_identify (ide_drive_t *drive, u8 cmd)
{
	ide_hwif_t *hwif = HWIF(drive);
	int rc;
	unsigned long hd_status;
	unsigned long timeout;
	u8 s = 0, a = 0;

	/* take a deep breath */
	msleep(50);

	if (IDE_CONTROL_REG) {
		a = hwif->INB(IDE_ALTSTATUS_REG);
		s = hwif->INB(IDE_STATUS_REG);
		if ((a ^ s) & ~INDEX_STAT) {
			printk(KERN_INFO "%s: probing with STATUS(0x%02x) instead of "
				"ALTSTATUS(0x%02x)\n", drive->name, s, a);
			/* ancient Seagate drives, broken interfaces */
			hd_status = IDE_STATUS_REG;
		} else {
			/* use non-intrusive polling */
			hd_status = IDE_ALTSTATUS_REG;
		}
	} else
		hd_status = IDE_STATUS_REG;

	/* set features register for atapi
	 * identify command to be sure of reply
	 */
	if ((cmd == WIN_PIDENTIFY))
		/* disable dma & overlap */
		hwif->OUTB(0, IDE_FEATURE_REG);

	/* ask drive for ID */
	hwif->OUTB(cmd, IDE_COMMAND_REG);

	timeout = ((cmd == WIN_IDENTIFY) ? WAIT_WORSTCASE : WAIT_PIDENTIFY) / 2;
	timeout += jiffies;
	do {
		if (time_after(jiffies, timeout)) {
			/* drive timed-out */
			return 1;
		}
		/* give drive a breather */
		msleep(50);
	} while ((hwif->INB(hd_status)) & BUSY_STAT);

	/* wait for IRQ and DRQ_STAT */
	msleep(50);
	if (OK_STAT((hwif->INB(IDE_STATUS_REG)), DRQ_STAT, BAD_R_STAT)) {
		unsigned long flags;

		/* local CPU only; some systems need this */
		local_irq_save(flags);
		/* drive returned ID */
		do_identify(drive, cmd);
		/* drive responded with ID */
		rc = 0;
		/* clear drive IRQ */
		(void) hwif->INB(IDE_STATUS_REG);
		local_irq_restore(flags);
	} else {
		/* drive refused ID */
		rc = 2;
	}
	return rc;
}

/**
 *	try_to_identify	-	try to identify a drive
 *	@drive: drive to probe
 *	@cmd: command to use
 *
 *	Issue the identify command and then do IRQ probing to
 *	complete the identification when needed by finding the
 *	IRQ the drive is attached to
 */
 
static int try_to_identify (ide_drive_t *drive, u8 cmd)
{
	ide_hwif_t *hwif = HWIF(drive);
	int retval;
	int autoprobe = 0;
	unsigned long cookie = 0;

	/*
	 * Disable device irq unless we need to
	 * probe for it. Otherwise we'll get spurious
	 * interrupts during the identify-phase that
	 * the irq handler isn't expecting.
	 */
	if (IDE_CONTROL_REG) {
		u8 ctl = drive->ctl | 2;
		if (!hwif->irq) {
			autoprobe = 1;
			cookie = probe_irq_on();
			/* enable device irq */
			ctl &= ~2;
		}
		hwif->OUTB(ctl, IDE_CONTROL_REG);
	}

	retval = actual_try_to_identify(drive, cmd);

	if (autoprobe) {
		int irq;
		/* mask device irq */
		hwif->OUTB(drive->ctl|2, IDE_CONTROL_REG);
		/* clear drive IRQ */
		(void) hwif->INB(IDE_STATUS_REG);
		udelay(5);
		irq = probe_irq_off(cookie);
		if (!hwif->irq) {
			if (irq > 0) {
				hwif->irq = irq;
			} else {
				/* Mmmm.. multiple IRQs..
				 * don't know which was ours
				 */
				printk("%s: IRQ probe failed (0x%lx)\n",
					drive->name, cookie);
			}
		}
	}
	return retval;
}


/**
 *	do_probe		-	probe an IDE device
 *	@drive: drive to probe
 *	@cmd: command to use
 *
 *	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, u8 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

	/* needed for some systems
	 * (e.g. crw9624 as drive0 with disk as slave)
	 */
	msleep(50);
	SELECT_DRIVE(drive);
	msleep(50);
	if (hwif->INB(IDE_SELECT_REG) != drive->select.all && !drive->present) {
		if (drive->select.b.unit != 0) {
			/* exit with drive0 selected */
			SELECT_DRIVE(&hwif->drives[0]);
			/* allow BUSY_STAT to assert & clear */
			msleep(50);
		}
		/* no i/f present: mmm.. this should be a 4 -ml */
		return 3;
	}

	if (OK_STAT((hwif->INB(IDE_STATUS_REG)), READY_STAT, BUSY_STAT) ||
	    drive->present || cmd == WIN_PIDENTIFY) {
		/* send cmd and wait */
		if ((rc = try_to_identify(drive, cmd))) {
			/* failed: try again */
			rc = try_to_identify(drive,cmd);
		}
		if (hwif->INB(IDE_STATUS_REG) == (BUSY_STAT|READY_STAT))
			return 4;

		if ((rc == 1 && cmd == WIN_PIDENTIFY) &&
			((drive->autotune == IDE_TUNE_DEFAULT) ||
			(drive->autotune == IDE_TUNE_AUTO))) {
			unsigned long timeout;
			printk("%s: no response (status = 0x%02x), "
				"resetting drive\n", drive->name,
				hwif->INB(IDE_STATUS_REG));
			msleep(50);
			hwif->OUTB(drive->select.all, IDE_SELECT_REG);
			msleep(50);
			hwif->OUTB(WIN_SRST, IDE_COMMAND_REG);
			timeout = jiffies;
			while (((hwif->INB(IDE_STATUS_REG)) & BUSY_STAT) &&
			       time_before(jiffies, timeout + WAIT_WORSTCASE))
				msleep(50);
			rc = try_to_identify(drive, cmd);
		}
		if (rc == 1)
			printk("%s: no response (status = 0x%02x)\n",
				drive->name, hwif->INB(IDE_STATUS_REG));
		/* ensure drive irq is clear */
		(void) hwif->INB(IDE_STATUS_REG);
	} else {
		/* not present or maybe ATAPI */