ide.c

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/*
 *  linux/drivers/ide/ide.c		Version 7.00beta2	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 multiple IDE interface driver, as evolved from hd.c.
 * It supports up to MAX_HWIFS IDE interfaces, on one or more IRQs
 *   (usually 14 & 15).
 * There can be up to two drives per interface, as per the ATA-2 spec.
 *
 * Primary:    ide0, port 0x1f0; major=3;  hda is minor=0; hdb is minor=64
 * Secondary:  ide1, port 0x170; major=22; hdc is minor=0; hdd is minor=64
 * Tertiary:   ide2, port 0x???; major=33; hde is minor=0; hdf is minor=64
 * Quaternary: ide3, port 0x???; major=34; hdg is minor=0; hdh is minor=64
 * ...
 *
 *  From hd.c:
 *  |
 *  | It traverses the request-list, using interrupts to jump between functions.
 *  | As nearly all functions can be called within interrupts, we may not sleep.
 *  | Special care is recommended.  Have Fun!
 *  |
 *  | modified by Drew Eckhardt to check nr of hd's from the CMOS.
 *  |
 *  | Thanks to Branko Lankester, [e-mail], who found a bug
 *  | in the early extended-partition checks and added DM partitions.
 *  |
 *  | Early work on error handling by Mika Liljeberg ([e-mail]).
 *  |
 *  | IRQ-unmask, drive-id, multiple-mode, support for ">16 heads",
 *  | and general streamlining by Mark Lord ([e-mail]).
 *
 *  October, 1994 -- Complete line-by-line overhaul for linux 1.1.x, by:
 *
 *	Mark Lord	([e-mail])		(IDE Perf.Pkg)
 *	Delman Lee	([e-mail])		("Mr. atdisk2")
 *	Scott Snyder	([e-mail])	(ATAPI IDE cd-rom)
 *
 *  This was a rewrite of just about everything from hd.c, though some original
 *  code is still sprinkled about.  Think of it as a major evolution, with
 *  inspiration from lots of linux users, esp.  [e-mail]
 *
 *  Version 1.0 ALPHA	initial code, primary i/f working okay
 *  Version 1.3 BETA	dual i/f on shared irq tested & working!
 *  Version 1.4 BETA	added auto probing for irq(s)
 *  Version 1.5 BETA	added ALPHA (untested) support for IDE cd-roms,
 *  ...
 * Version 5.50		allow values as small as 20 for idebus=
 * Version 5.51		force non io_32bit in drive_cmd_intr()
 *			change delay_10ms() to delay_50ms() to fix problems
 * Version 5.52		fix incorrect invalidation of removable devices
 *			add "hdx=slow" command line option
 * Version 5.60		start to modularize the driver; the disk and ATAPI
 *			 drivers can be compiled as loadable modules.
 *			move IDE probe code to ide-probe.c
 *			move IDE disk code to ide-disk.c
 *			add support for generic IDE device subdrivers
 *			add m68k code from Geert Uytterhoeven
 *			probe all interfaces by default
 *			add ioctl to (re)probe an interface
 * Version 6.00		use per device request queues
 *			attempt to optimize shared hwgroup performance
 *			add ioctl to manually adjust bandwidth algorithms
 *			add kerneld support for the probe module
 *			fix bug in ide_error()
 *			fix bug in the first ide_get_lock() call for Atari
 *			don't flush leftover data for ATAPI devices
 * Version 6.01		clear hwgroup->active while the hwgroup sleeps
 *			support HDIO_GETGEO for floppies
 * Version 6.02		fix ide_ack_intr() call
 *			check partition table on floppies
 * Version 6.03		handle bad status bit sequencing in ide_wait_stat()
 * Version 6.10		deleted old entries from this list of updates
 *			replaced triton.c with ide-dma.c generic PCI DMA
 *			added support for BIOS-enabled UltraDMA
 *			rename all "promise" things to "pdc4030"
 *			fix EZ-DRIVE handling on small disks
 * Version 6.11		fix probe error in ide_scan_devices()
 *			fix ancient "jiffies" polling bugs
 *			mask all hwgroup interrupts on each irq entry
 * Version 6.12		integrate ioctl and proc interfaces
 *			fix parsing of "idex=" command line parameter
 * Version 6.13		add support for ide4/ide5 courtesy [e-mail]
 * Version 6.14		fixed IRQ sharing among PCI devices
 * Version 6.15		added SMP awareness to IDE drivers
 * Version 6.16		fixed various bugs; even more SMP friendly
 * Version 6.17		fix for newest EZ-Drive problem
 * Version 6.18		default unpartitioned-disk translation now "BIOS LBA"
 * Version 6.19		Re-design for a UNIFORM driver for all platforms,
 *			  model based on suggestions from Russell King and
 *			  Geert Uytterhoeven
 *			Promise DC4030VL now supported.
 *			add support for ide6/ide7
 *			delay_50ms() changed to ide_delay_50ms() and exported.
 * Version 6.20		Added/Fixed Generic ATA-66 support and hwif detection.
 *			Added hdx=flash to allow for second flash disk
 *			  detection w/o the hang loop.
 *			Added support for ide8/ide9
 *			Added idex=ata66 for the quirky chipsets that are
 *			  ATA-66 compliant, but have yet to determine a method
 *			  of verification of the 80c cable presence.
 *			  Specifically Promise's PDC20262 chipset.
 * Version 6.21		Fixing/Fixed SMP spinlock issue with insight from an old
 *			  hat that clarified original low level driver design.
 * Version 6.30		Added SMP support; fixed multmode issues.  -ml
 * Version 6.31		Debug Share INTR's and request queue streaming
 *			Native ATA-100 support
 *			Prep for Cascades Project
 * Version 7.00alpha	First named revision of ide rearrange
 *
 *  Some additional driver compile-time options are in ./include/linux/ide.h
 *
 *  To do, in likely order of completion:
 *	- modify kernel to obtain BIOS geometry for drives on 2nd/3rd/4th i/f
 *
 */

#define	REVISION	"Revision: 7.00alpha2"
#define	VERSION		"Id: ide.c 7.00a2 20020906"

#undef REALLY_SLOW_IO		/* most systems can safely undef this */

#define _IDE_C			/* Tell ide.h it's really us */

#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/blkpg.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/pci.h>
#include <linux/delay.h>
#include <linux/ide.h>
#include <linux/devfs_fs_kernel.h>
#include <linux/completion.h>
#include <linux/reboot.h>
#include <linux/cdrom.h>
#include <linux/seq_file.h>
#include <linux/device.h>
#include <linux/bitops.h>

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


/* default maximum number of failures */
#define IDE_DEFAULT_MAX_FAILURES 	1

static const u8 ide_hwif_to_major[] = { IDE0_MAJOR, IDE1_MAJOR,
					IDE2_MAJOR, IDE3_MAJOR,
					IDE4_MAJOR, IDE5_MAJOR,
					IDE6_MAJOR, IDE7_MAJOR,
					IDE8_MAJOR, IDE9_MAJOR };

static int idebus_parameter;	/* holds the "idebus=" parameter */
static int system_bus_speed;	/* holds what we think is VESA/PCI bus speed */
static int initializing;	/* set while initializing built-in drivers */

DECLARE_MUTEX(ide_cfg_sem);
 __cacheline_aligned_in_smp DEFINE_SPINLOCK(ide_lock);

#ifdef CONFIG_BLK_DEV_IDEPCI
static int ide_scan_direction; /* THIS was formerly 2.2.x pci=reverse */
#endif

#ifdef CONFIG_IDEDMA_AUTO
int noautodma = 0;
#else
int noautodma = 1;
#endif

EXPORT_SYMBOL(noautodma);

/*
 * This is declared extern in ide.h, for access by other IDE modules:
 */
ide_hwif_t ide_hwifs[MAX_HWIFS];	/* master data repository */

EXPORT_SYMBOL(ide_hwifs);

/*
 * Do not even *think* about calling this!
 */
static void init_hwif_data(ide_hwif_t *hwif, unsigned int index)
{
	unsigned int unit;

	/* bulk initialize hwif & drive info with zeros */
	memset(hwif, 0, sizeof(ide_hwif_t));

	/* fill in any non-zero initial values */
	hwif->index	= index;
	hwif->major	= ide_hwif_to_major[index];

	hwif->name[0]	= 'i';
	hwif->name[1]	= 'd';
	hwif->name[2]	= 'e';
	hwif->name[3]	= '0' + index;

	hwif->bus_state	= BUSSTATE_ON;

	hwif->atapi_dma = 0;		/* disable all atapi dma */ 
	hwif->ultra_mask = 0x80;	/* disable all ultra */
	hwif->mwdma_mask = 0x80;	/* disable all mwdma */
	hwif->swdma_mask = 0x80;	/* disable all swdma */

	sema_init(&hwif->gendev_rel_sem, 0);

	default_hwif_iops(hwif);
	default_hwif_transport(hwif);
	for (unit = 0; unit < MAX_DRIVES; ++unit) {
		ide_drive_t *drive = &hwif->drives[unit];

		drive->media			= ide_disk;
		drive->select.all		= (unit<<4)|0xa0;
		drive->hwif			= hwif;
		drive->ctl			= 0x08;
		drive->ready_stat		= READY_STAT;
		drive->bad_wstat		= BAD_W_STAT;
		drive->special.b.recalibrate	= 1;
		drive->special.b.set_geometry	= 1;
		drive->name[0]			= 'h';
		drive->name[1]			= 'd';
		drive->name[2]			= 'a' + (index * MAX_DRIVES) + unit;
		drive->max_failures		= IDE_DEFAULT_MAX_FAILURES;
		drive->using_dma		= 0;
		drive->is_flash			= 0;
		drive->vdma			= 0;
		INIT_LIST_HEAD(&drive->list);
		sema_init(&drive->gendev_rel_sem, 0);
	}
}

static void init_hwif_default(ide_hwif_t *hwif, unsigned int index)
{
	hw_regs_t hw;

	memset(&hw, 0, sizeof(hw_regs_t));

	ide_init_hwif_ports(&hw, ide_default_io_base(index), 0, &hwif->irq);

	memcpy(&hwif->hw, &hw, sizeof(hw));
	memcpy(hwif->io_ports, hw.io_ports, sizeof(hw.io_ports));

	hwif->noprobe = !hwif->io_ports[IDE_DATA_OFFSET];
#ifdef CONFIG_BLK_DEV_HD
	if (hwif->io_ports[IDE_DATA_OFFSET] == HD_DATA)
		hwif->noprobe = 1;	/* may be overridden by ide_setup() */
#endif
}

extern void ide_arm_init(void);

/*
 * init_ide_data() sets reasonable default values into all fields
 * of all instances of the hwifs and drives, but only on the first call.
 * Subsequent calls have no effect (they don't wipe out anything).
 *
 * This routine is normally called at driver initialization time,
 * but may also be called MUCH earlier during kernel "command-line"
 * parameter processing.  As such, we cannot depend on any other parts
 * of the kernel (such as memory allocation) to be functioning yet.
 *
 * This is too bad, as otherwise we could dynamically allocate the
 * ide_drive_t structs as needed, rather than always consuming memory
 * for the max possible number (MAX_HWIFS * MAX_DRIVES) of them.
 *
 * FIXME: We should stuff the setup data into __init and copy the
 * relevant hwifs/allocate them properly during boot.
 */
#define MAGIC_COOKIE 0x12345678
static void __init init_ide_data (void)
{
	ide_hwif_t *hwif;
	unsigned int index;
	static unsigned long magic_cookie = MAGIC_COOKIE;

	if (magic_cookie != MAGIC_COOKIE)
		return;		/* already initialized */
	magic_cookie = 0;

	/* Initialise all interface structures */
	for (index = 0; index < MAX_HWIFS; ++index) {
		hwif = &ide_hwifs[index];
		init_hwif_data(hwif, index);
		init_hwif_default(hwif, index);
#if !defined(CONFIG_PPC32) || !defined(CONFIG_PCI)
		hwif->irq = hwif->hw.irq =
			ide_init_default_irq(hwif->io_ports[IDE_DATA_OFFSET]);
#endif
	}
#ifdef CONFIG_IDE_ARM
	initializing = 1;
	ide_arm_init();
	initializing = 0;
#endif
}

/**
 *	ide_system_bus_speed	-	guess bus speed
 *
 *	ide_system_bus_speed() returns what we think is the system VESA/PCI
 *	bus speed (in MHz). This is used for calculating interface PIO timings.
 *	The default is 40 for known PCI systems, 50 otherwise.
 *	The "idebus=xx" parameter can be used to override this value.
 *	The actual value to be used is computed/displayed the first time
 *	through. Drivers should only use this as a last resort.
 *
 *	Returns a guessed speed in MHz.
 */

static int ide_system_bus_speed(void)
{
#ifdef CONFIG_PCI
	static struct pci_device_id pci_default[] = {
		{ PCI_DEVICE(PCI_ANY_ID, PCI_ANY_ID) },
		{ }
	};
#else
#define pci_default 0
#endif /* CONFIG_PCI */

	if (!system_bus_speed) {
		if (idebus_parameter) {
			/* user supplied value */
			system_bus_speed = idebus_parameter;
		} else if (pci_dev_present(pci_default)) {
			/* safe default value for PCI */
			system_bus_speed = 33;
		} else {
			/* safe default value for VESA and PCI */
			system_bus_speed = 50;
		}
		printk(KERN_INFO "ide: Assuming %dMHz system bus speed "
			"for PIO modes%s\n", system_bus_speed,
			idebus_parameter ? "" : "; override with idebus=xx");
	}
	return system_bus_speed;
}

#ifdef CONFIG_PROC_FS
struct proc_dir_entry *proc_ide_root;
#endif

static struct resource* hwif_request_region(ide_hwif_t *hwif,
					    unsigned long addr, int num)
{
	struct resource *res = request_region(addr, num, hwif->name);

	if (!res)
		printk(KERN_ERR "%s: I/O resource 0x%lX-0x%lX not free.\n",
				hwif->name, addr, addr+num-1);
	return res;
}

/**
 *	ide_hwif_request_regions - request resources for IDE
 *	@hwif: interface to use
 *
 *	Requests all the needed resources for an interface.
 *	Right now core IDE code does this work which is deeply wrong.
 *	MMIO leaves it to the controller driver,
 *	PIO will migrate this way over time.
 */

int ide_hwif_request_regions(ide_hwif_t *hwif)
{
	unsigned long addr;
	unsigned int i;

	if (hwif->mmio == 2)
		return 0;
	BUG_ON(hwif->mmio == 1);
	addr = hwif->io_ports[IDE_CONTROL_OFFSET];
	if (addr && !hwif_request_region(hwif, addr, 1))
		goto control_region_busy;
	hwif->straight8 = 0;
	addr = hwif->io_ports[IDE_DATA_OFFSET];
	if ((addr | 7) == hwif->io_ports[IDE_STATUS_OFFSET]) {
		if (!hwif_request_region(hwif, addr, 8))
			goto data_region_busy;
		hwif->straight8 = 1;
		return 0;
	}
	for (i = IDE_DATA_OFFSET; i <= IDE_STATUS_OFFSET; i++) {
		addr = hwif->io_ports[i];
		if (!hwif_request_region(hwif, addr, 1)) {
			while (--i)
				release_region(addr, 1);
			goto data_region_busy;
		}
	}
	return 0;

data_region_busy:
	addr = hwif->io_ports[IDE_CONTROL_OFFSET];
	if (addr)
		release_region(addr, 1);
control_region_busy:
	/* If any errors are return, we drop the hwif interface. */
	return -EBUSY;
}

/**
 *	ide_hwif_release_regions - free IDE resources
 *
 *	Note that we only release the standard ports,
 *	and do not even try to handle any extra ports
 *	allocated for weird IDE interface chipsets.
 *
 *	Note also that we don't yet handle mmio resources here. More
 *	importantly our caller should be doing this so we need to 
 *	restructure this as a helper function for drivers.
 */

void ide_hwif_release_regions(ide_hwif_t *hwif)
{
	u32 i = 0;

	if (hwif->mmio == 2)
		return;
	if (hwif->io_ports[IDE_CONTROL_OFFSET])
		release_region(hwif->io_ports[IDE_CONTROL_OFFSET], 1);
	if (hwif->straight8) {
		release_region(hwif->io_ports[IDE_DATA_OFFSET], 8);
		return;
	}
	for (i = IDE_DATA_OFFSET; i <= IDE_STATUS_OFFSET; i++)
		if (hwif->io_ports[i])
			release_region(hwif->io_ports[i], 1);
}

/**
 *	ide_hwif_restore	-	restore hwif to template
 *	@hwif: hwif to update
 *	@tmp_hwif: template
 *
 *	Restore hwif to a previous state by copying most settngs
 *	from the template.
 */

static void ide_hwif_restore(ide_hwif_t *hwif, ide_hwif_t *tmp_hwif)
{
	hwif->hwgroup			= tmp_hwif->hwgroup;

	hwif->gendev.parent		= tmp_hwif->gendev.parent;

	hwif->proc			= tmp_hwif->proc;

	hwif->major			= tmp_hwif->major;
	hwif->straight8			= tmp_hwif->straight8;
	hwif->bus_state			= tmp_hwif->bus_state;

	hwif->atapi_dma			= tmp_hwif->atapi_dma;
	hwif->ultra_mask		= tmp_hwif->ultra_mask;
	hwif->mwdma_mask		= tmp_hwif->mwdma_mask;
	hwif->swdma_mask		= tmp_hwif->swdma_mask;

	hwif->chipset			= tmp_hwif->chipset;
	hwif->hold			= tmp_hwif->hold;

#ifdef CONFIG_BLK_DEV_IDEPCI
	hwif->pci_dev			= tmp_hwif->pci_dev;
	hwif->cds			= tmp_hwif->cds;
#endif

	hwif->tuneproc			= tmp_hwif->tuneproc;
	hwif->speedproc			= tmp_hwif->speedproc;
	hwif->selectproc		= tmp_hwif->selectproc;
	hwif->reset_poll		= tmp_hwif->reset_poll;
	hwif->pre_reset			= tmp_hwif->pre_reset;
	hwif->resetproc			= tmp_hwif->resetproc;
	hwif->intrproc			= tmp_hwif->intrproc;
	hwif->maskproc			= tmp_hwif->maskproc;
	hwif->quirkproc			= tmp_hwif->quirkproc;
	hwif->busproc			= tmp_hwif->busproc;

	hwif->ata_input_data		= tmp_hwif->ata_input_data;
	hwif->ata_output_data		= tmp_hwif->ata_output_data;
	hwif->atapi_input_bytes		= tmp_hwif->atapi_input_bytes;
	hwif->atapi_output_bytes	= tmp_hwif->atapi_output_bytes;

	hwif->dma_setup			= tmp_hwif->dma_setup;
	hwif->dma_exec_cmd		= tmp_hwif->dma_exec_cmd;
	hwif->dma_start			= tmp_hwif->dma_start;
	hwif->ide_dma_end		= tmp_hwif->ide_dma_end;