ide-probe.c

ep9315平台下硬盘驱动的源码

/*
 *  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.
 *
 * 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;
 * Version 1.06		stream line request queue and prep for cascade project.
 * Version 1.07		max_sect <= 255; slower disks would get behind and
 * 			then fall over when they get to 256.	Paul G.
 * Version 1.10		Update set for new IDE. drive->id is now always
 *			valid after probe time even with noprobe
 */

#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/slab.h>
#include <linux/delay.h>
#include <linux/ide.h>
#include <linux/spinlock.h>
#include <linux/pci.h>
#include <linux/kmod.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;
}
		
/**
 *	drive_is_flashcard	-	check for compact flash
 *	@drive: drive to check
 *
 *	CompactFlash cards and their brethern pretend to be removable
 *	hard disks, except:
 * 		(1) they never have a slave unit, and
 *		(2) they don't have doorlock mechanisms.
 *	This test catches them, and is invoked elsewhere when setting
 *	appropriate config bits.
 *
 *	FIXME: This treatment is probably applicable for *all* PCMCIA (PC CARD)
 *	devices, so in linux 2.3.x we should change this to just treat all
 *	PCMCIA  drives this way, and get rid of the model-name tests below
 *	(too big of an interface change for 2.4.x).
 *	At that time, we might also consider parameterizing the timeouts and
 *	retries, since these are MUCH faster than mechanical drives. -M.Lord
 */
 
static inline int drive_is_flashcard (ide_drive_t *drive)
{
	struct hd_driveid *id = drive->id;

	if (drive->removable && id != NULL) {
		if (id->config == 0x848a) return 1;	/* CompactFlash */
		if (!strncmp(id->model, "KODAK ATA_FLASH", 15)	/* Kodak */
		 || !strncmp(id->model, "Hitachi CV", 10)	/* Hitachi */
		 || !strncmp(id->model, "SunDisk SDCFB", 13)	/* SunDisk */
		 || !strncmp(id->model, "HAGIWARA HPC", 12)	/* Hagiwara */
		 || !strncmp(id->model, "LEXAR ATA_FLASH", 15)	/* Lexar */
		 || !strncmp(id->model, "ATA_FLASH", 9))	/* Simple Tech */
		{
			return 1;	/* yes, it is a flash memory card */
		}
	}
	return 0;	/* no, it is not a flash memory card */
}

/**
 *	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;

	/* called with interrupts disabled! */
	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 (!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);
		goto err_misc;
	}
#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 */
			/* 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);

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

	/* we depend on this a lot! */
	id->model[sizeof(id->model)-1] = '\0';
	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 ");
#ifdef CONFIG_BLK_DEV_PDC4030
		if (hwif->channel == 1 && hwif->chipset == ide_pdc4030) {
			printk(" -- not supported on 2nd Promise port\n");
			goto err_misc;
		}
#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");
						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;
		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:
	 */
	drive->is_flash = 0;
	if (drive_is_flashcard(drive)) {
#if 0
		/* The new IDE adapter widgets don't follow this heuristic
		   so we must nowdays just bite the bullet and take the
		   probe hit */	
		ide_drive_t *mate = &hwif->drives[1^drive->select.b.unit];		
		if (!mate->ata_flash) {
			mate->present = 0;
			mate->noprobe = 1;
		}
#endif		
		drive->is_flash = 1;
	}
	drive->media = ide_disk;
	printk("%s DISK drive\n", (drive->is_flash) ? "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: comamnd 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;
	ide_ioreg_t hd_status;
	unsigned long timeout;
	u8 s = 0, a = 0;

	if (IDE_CONTROL_REG) {
		/* take a deep breath */
		ide_delay_50ms();
		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 {
		ide_delay_50ms();
		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);

	if (hwif->identify != NULL) {
		if (hwif->identify(drive))
			return 1;
	} else {
		/* 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 */
		ide_delay_50ms();
	} while ((hwif->INB(hd_status)) & BUSY_STAT);

	/* wait for IRQ and DRQ_STAT */
	ide_delay_50ms();
	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: comamnd 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;

	if (IDE_CONTROL_REG && !hwif->irq) {
		autoprobe = 1;
		cookie = probe_irq_on();
		/* enable device irq */
		hwif->OUTB(drive->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);
#ifdef CONFIG_BLK_DEV_CMD640
#ifdef CMD640_DUMP_REGS
				if (hwif->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 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)
	 */
	ide_delay_50ms();
	SELECT_DRIVE(drive);
	ide_delay_50ms();
	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 */
			ide_delay_50ms();
		}
		/* 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);
		}