ide-probe.c

基于组件方式开发操作系统的OSKIT源代码

/*
 *  linux/drivers/block/ide-probe.c	Version 1.04  March 10, 1999
 *
 *  Copyright (C) 1994-1998  Linus Torvalds & authors (see below)
 */

/*
 *  Mostly written by Mark Lord <[e-mail]>
 *                and Gadi Oxman <[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
 */

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

#include "ide.h"

#ifdef OSKIT
/* This proto needs to be someplace else */
int	oskit_linux_ofw_probe_ide(ide_hwif_t *hwif);
#endif

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 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);

	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:
				printk ("CDROM");
				drive->removable = 1;
				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];
		mate->present = 0;
		mate->noprobe = 1;
	}
	drive->media = ide_disk;
	printk("ATA DISK drive\n");
	return;
}

/*
 * Delay for *at least* 50ms.  As we don't know how much time is left
 * until the next tick occurs, we wait an extra tick to be safe.
 * This is used only during the probing/polling for drives at boot time.
 */
static void delay_50ms (void)
{
	unsigned long timeout = jiffies + ((HZ + 19)/20) + 1;
	while (0 < (signed long)(timeout - jiffies));
}

/*
 * 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 (!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 */
	}

	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 */

#if CONFIG_BLK_DEV_PDC4030
	if (IS_PDC4030_DRIVE) {
		extern int pdc4030_cmd(ide_drive_t *, byte);
		if (pdc4030_cmd(drive,PROMISE_IDENTIFY)) {
			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 */
		}
		delay_50ms();		/* give drive a breather */
	} while (IN_BYTE(hd_status) & BUSY_STAT);

	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 (!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
	SELECT_DRIVE(hwif,drive);
	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 */
			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());
			delay_50ms();
			OUT_BYTE (drive->select.all, IDE_SELECT_REG);
			delay_50ms();
			OUT_BYTE(WIN_SRST, IDE_COMMAND_REG);
			timeout = jiffies;
			while ((GET_STAT() & BUSY_STAT) && time_before(jiffies, timeout + WAIT_WORSTCASE))
				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 */
		delay_50ms();
		(void) GET_STAT();		/* ensure drive irq is clear */
	}
	return rc;
}

/*
 * 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->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 */
}

/*
 * We query CMOS about hard disks : it could be that we have a SCSI/ESDI/etc
 * controller that is BIOS compatible with ST-506, and thus showing up in our
 * BIOS table, but not register compatible, and therefore not present in CMOS.
 *
 * Furthermore, we will assume that our ST-506 drives <if any> are the primary
 * drives in the system -- the ones reflected as drive 1 or 2.  The first
 * drive is stored in the high nibble of CMOS byte 0x12, the second in the low
 * nibble.  This will be either a 4 bit drive type or 0xf indicating use byte
 * 0x19 for an 8 bit type, drive 1, 0x1a for drive 2 in CMOS.  A non-zero value
 * means we have an AT controller hard disk for that drive.
 *
 * Of course, there is no guarantee that either drive is actually on the
 * "primary" IDE interface, but we don't bother trying to sort that out here.
 * If a drive is not actually on the primary interface, then these parameters
 * will be ignored.  This results in the user having to supply the logical
 * drive geometry as a boot parameter for each drive not on the primary i/f.
 *
 * The only "perfect" way to handle this would be to modify the setup.[cS] code
 * to do BIOS calls Int13h/Fn08h and Int13h/Fn48h to get all of the drive info
 * for us during initialization.  I have the necessary docs -- any takers?  -ml
 */
static void probe_cmos_for_drives (ide_hwif_t *hwif)
{
#ifdef __i386__
	extern struct drive_info_struct drive_info;
	byte cmos_disks, *BIOS = (byte *) &drive_info;
	int unit;

#ifdef CONFIG_BLK_DEV_PDC4030
	if (hwif->chipset == ide_pdc4030 && hwif->channel != 0)
		return;
#endif /* CONFIG_BLK_DEV_PDC4030 */
	outb_p(0x12,0x70);		/* specify CMOS address 0x12 */
	cmos_disks = inb_p(0x71);	/* read the data from 0x12 */
	/* Extract drive geometry from CMOS+BIOS if not already setup */
	for (unit = 0; unit < MAX_DRIVES; ++unit) {
		ide_drive_t *drive = &hwif->drives[unit];
		if ((cmos_disks & (0xf0 >> (unit*4))) && !drive->present && !drive->nobios) {
			drive->cyl   = drive->bios_cyl  = *(unsigned short *)BIOS;
			drive->head  = drive->bios_head = *(BIOS+2);
			drive->sect  = drive->bios_sect = *(BIOS+14);
			drive->ctl   = *(BIOS+8);
			drive->present = 1;
		}
		BIOS += 16;
	}
#endif
}

/*
 * 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;

#ifdef OSKIT_ARM32_SHARK