ide.c

GNU Mach 微内核源代码, 基于美国卡内基美隆大学的 Mach 研究项目

/*
 *  linux/drivers/block/ide.c	Version 5.53  Jun  24, 1997
 *
 *  Copyright (C) 1994-1996  Linus Torvalds & authors (see below)
 */
#define _IDE_C		/* needed by <linux/blk.h> */

/*
 *  Maintained by Mark Lord  <[e-mail]>
 *            and Gadi Oxman <[e-mail]>
 *
 * This is the multiple IDE interface driver, as evolved from hd.c.
 * It supports up to four 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
 *
 * It is easy to extend ide.c to handle more than four interfaces:
 *
 *	Change the MAX_HWIFS constant in ide.h.
 *
 *	Define some new major numbers (in major.h), and insert them into
 *	the ide_hwif_to_major table in ide.c.
 *
 *	Fill in the extra values for the new interfaces into the two tables
 *	inside ide.c:  default_io_base[]  and  default_irqs[].
 *
 *	Create the new request handlers by cloning "do_ide3_request()"
 *	for each new interface, and add them to the switch statement
 *	in the ide_init() function in ide.c.
 *
 *	Recompile, create the new /dev/ entries, and it will probably work.
 *
 *  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 3.5		correct the bios_cyl field if it's too small
 *  (linux 1.1.76)	 (to help fdisk with brain-dead BIOSs)
 *  Version 3.6		cosmetic corrections to comments and stuff
 *  (linux 1.1.77)	reorganise probing code to make it understandable
 *			added halfway retry to probing for drive identification
 *			added "hdx=noprobe" command line option
 *			allow setting multmode even when identification fails
 *  Version 3.7		move set_geometry=1 from do_identify() to ide_init()
 *			increase DRQ_WAIT to eliminate nuisance messages
 *			wait for DRQ_STAT instead of DATA_READY during probing
 *			  (courtesy of Gary Thomas [e-mail])
 *  Version 3.8		fixed byte-swapping for confused Mitsumi cdrom drives
 *			update of ide-cd.c from Scott, allows blocksize=1024
 *			cdrom probe fixes, inspired by [e-mail]
 *  Version 3.9		don't use LBA if lba_capacity looks funny
 *			correct the drive capacity calculations
 *			fix probing for old Seagates without IDE_ALTSTATUS_REG
 *			fix byte-ordering for some NEC cdrom drives
 *  Version 3.10	disable multiple mode by default; was causing trouble
 *  Version 3.11	fix mis-identification of old WD disks as cdroms
 *  Version 3,12	simplify logic for selecting initial mult_count
 *			  (fixes problems with buggy WD drives)
 *  Version 3.13	remove excess "multiple mode disabled" messages
 *  Version 3.14	fix ide_error() handling of BUSY_STAT
 *			fix byte-swapped cdrom strings (again.. arghh!)
 *			ignore INDEX bit when checking the ALTSTATUS reg
 *  Version 3.15	add SINGLE_THREADED flag for use with dual-CMD i/f
 *			ignore WRERR_STAT for non-write operations
 *			added vlb_sync support for DC-2000A & others,
 *			 (incl. some Promise chips), courtesy of Frank Gockel
 *  Version 3.16	convert vlb_32bit and vlb_sync into runtime flags
 *			add ioctls to get/set VLB flags (HDIO_[SG]ET_CHIPSET)
 *			rename SINGLE_THREADED to SUPPORT_SERIALIZE,
 *			add boot flag to "serialize" operation for CMD i/f
 *			add optional support for DTC2278 interfaces,
 *			 courtesy of [e-mail] (Dyan Wile).
 *			add boot flag to enable "dtc2278" probe
 *			add probe to avoid EATA (SCSI) interfaces,
 *			 courtesy of [e-mail].
 *  Version 4.00	tidy up verify_area() calls - [e-mail]
 *			add flag to ignore WRERR_STAT for some drives
 *			 courtesy of [e-mail]
 *			assembly syntax tweak to vlb_sync
 *			removable drive support from [e-mail]
 *			add transparent support for DiskManager-6.0x "Dynamic
 *			 Disk Overlay" (DDO), most of this is in genhd.c
 *			eliminate "multiple mode turned off" message at boot
 *  Version 4.10	fix bug in ioctl for "hdparm -c3"
 *			fix DM6:DDO support -- now works with LILO, fdisk, ...
 *			don't treat some naughty WD drives as removable
 *  Version 4.11	updated DM6 support using info provided by OnTrack
 *  Version 5.00	major overhaul, multmode setting fixed, vlb_sync fixed
 *			added support for 3rd/4th/alternative IDE ports
 *			created ide.h; ide-cd.c now compiles separate from ide.c
 *			hopefully fixed infinite "unexpected_intr" from cdroms
 *			zillions of other changes and restructuring
 *			somehow reduced overall memory usage by several kB
 *			probably slowed things down slightly, but worth it
 *  Version 5.01	AT LAST!!  Finally understood why "unexpected_intr"
 *			 was happening at various times/places:  whenever the
 *			 ide-interface's ctl_port was used to "mask" the irq,
 *			 it also would trigger an edge in the process of masking
 *			 which would result in a self-inflicted interrupt!!
 *			 (such a stupid way to build a hardware interrupt mask).
 *			 This is now fixed (after a year of head-scratching).
 *  Version 5.02	got rid of need for {enable,disable}_irq_list()
 *  Version 5.03	tune-ups, comments, remove "busy wait" from drive resets
 *			removed PROBE_FOR_IRQS option -- no longer needed
 *			OOOPS!  fixed "bad access" bug for 2nd drive on an i/f
 *  Version 5.04	changed "ira %d" to "irq %d" in DEBUG message
 *			added more comments, cleaned up unexpected_intr()
 *			OOOPS!  fixed null pointer problem in ide reset code
 *			added autodetect for Triton chipset -- no effect yet
 *  Version 5.05	OOOPS!  fixed bug in revalidate_disk()
 *			OOOPS!  fixed bug in ide_do_request()
 *			added ATAPI reset sequence for cdroms
 *  Version 5.10	added Bus-Mastered DMA support for Triton Chipset
 *			some (mostly) cosmetic changes
 *  Version 5.11	added ht6560b support by [e-mail]
 *			reworked PCI scanning code
 *			added automatic RZ1000 detection/support
 *			added automatic PCI CMD640 detection/support
 *			added option for VLB CMD640 support
 *			tweaked probe to find cdrom on hdb with disks on hda,hdc
 *  Version 5.12	some performance tuning
 *			added message to alert user to bad /dev/hd[cd] entries
 *			OOOPS!  fixed bug in atapi reset
 *			driver now forces "serialize" again for all cmd640 chips
 *			noticed REALLY_SLOW_IO had no effect, moved it to ide.c
 *			made do_drive_cmd() into public ide_do_drive_cmd()
 *  Version 5.13	fixed typo ('B'), thanks to [e-mail]
 *			fixed ht6560b support
 *  Version 5.13b (sss)	fix problem in calling ide_cdrom_setup()
 *			don't bother invalidating nonexistent partitions
 *  Version 5.14	fixes to cmd640 support.. maybe it works now(?)
 *			added & tested full EZ-DRIVE support -- don't use LILO!
 *			don't enable 2nd CMD640 PCI port during init - conflict
 *  Version 5.15	bug fix in init_cmd640_vlb()
 *			bug fix in interrupt sharing code
 *  Version 5.16	ugh.. fix "serialize" support, broken in 5.15
 *			remove "Huh?" from cmd640 code
 *			added qd6580 interface speed select from Colten Edwards
 *  Version 5.17	kludge around bug in BIOS32 on Intel triton motherboards
 *  Version 5.18	new CMD640 code, moved to cmd640.c, #include'd for now
 *			new UMC8672 code, moved to umc8672.c, #include'd for now
 *			disallow turning on DMA when h/w not capable of DMA
 *  Version 5.19	fix potential infinite timeout on resets
 *			extend reset poll into a general purpose polling scheme
 *			add atapi tape drive support from Gadi Oxman
 *			simplify exit from _intr routines -- no IDE_DO_REQUEST
 *  Version 5.20	leave current rq on blkdev request list during I/O
 *			generalized ide_do_drive_cmd() for tape/cdrom driver use
 *  Version 5.21	fix nasty cdrom/tape bug (ide_preempt was messed up)
 *  Version 5.22	fix ide_xlate_1024() to work with/without drive->id
 *  Version 5.23	miscellaneous touch-ups
 *  Version 5.24	fix #if's for SUPPORT_CMD640
 *  Version 5.25	more touch-ups, fix cdrom resets, ...
 *			cmd640.c now configs/compiles separate from ide.c
 *  Version 5.26	keep_settings now maintains the using_dma flag
 *			fix [EZD] remap message to only output at boot time
 *			fix "bad /dev/ entry" message to say hdc, not hdc0
 *			fix ide_xlate_1024() to respect user specified CHS
 *			use CHS from partn table if it looks translated
 *			re-merged flags chipset,vlb_32bit,vlb_sync into io_32bit
 *			keep track of interface chipset type, when known
 *			add generic PIO mode "tuneproc" mechanism
 *			fix cmd640_vlb option
 *			fix ht6560b support (was completely broken)
 *			umc8672.c now configures/compiles separate from ide.c
 *			move dtc2278 support to dtc2278.c
 *			move ht6560b support to ht6560b.c
 *			move qd6580  support to qd6580.c
 *			add  ali14xx support in ali14xx.c
 * Version 5.27		add [no]autotune parameters to help cmd640
 *			move rz1000  support to rz1000.c
 * Version 5.28		#include "ide_modes.h"
 *			fix disallow_unmask: now per-interface "no_unmask" bit
 *			force io_32bit to be the same on drive pairs of dtc2278
 *			improved IDE tape error handling, and tape DMA support
 *			bugfix in ide_do_drive_cmd() for cdroms + serialize
 * Version 5.29		fixed non-IDE check for too many physical heads
 *			don't use LBA if capacity is smaller than CHS
 * Version 5.30		remove real_devices kludge, formerly used by genhd.c
 * Version 5.32		change "KB" to "kB"
 *			fix serialize (was broken in kernel 1.3.72)
 *			add support for "hdparm -I"
 *			use common code for disk/tape/cdrom IDE_DRIVE_CMDs
 *			add support for Promise DC4030VL caching card
 *			improved serialize support
 *			put partition check back into alphabetical order
 *			add config option for PCMCIA baggage
 *			try to make PCMCIA support safer to use
 *			improve security on ioctls(): all are suser() only
 * Version 5.33		improve handling of HDIO_DRIVE_CMDs that read data
 * Version 5.34		fix irq-sharing problem from 5.33
 *			fix cdrom ioctl problem from 5.33
 * Version 5.35		cosmetic changes
 *			fix cli() problem in try_to_identify()
 * Version 5.36		fixes to optional PCMCIA support
 * Version 5.37		don't use DMA when "noautotune" is specified
 * Version 5.37a (go)	fix shared irq probing (was broken in kernel 1.3.72)
 *			call unplug_device() from ide_do_drive_cmd()
 * Version 5.38		add "hdx=none" option, courtesy of Joel Maslak
 *			mask drive irq after use, if sharing with another hwif
 *			add code to help debug weird cmd640 problems
 * Version 5.39		fix horrible error in earlier irq sharing "fix"
 * Version 5.40		fix serialization -- was broken in 5.39
 *			help sharing by masking device irq after probing
 * Version 5.41		more fixes to irq sharing/serialize detection
 *			disable io_32bit by default on drive reset
 * Version 5.42		simplify irq-masking after probe
 *			fix NULL pointer deref in save_match()
 * Version 5.43		Ugh.. unexpected_intr is back: try to exterminate it
 * Version 5.44		Fix for "irq probe failed" on cmd640
 *			change path on message regarding MAKEDEV.ide
 *			add a throttle to the unexpected_intr() messages
 * Version 5.45		fix ugly parameter parsing bugs (thanks Derek)
 *			include Gadi's magic fix for cmd640 unexpected_intr
 *			include mc68000 patches from Geert Uytterhoeven
 *			add Gadi's fix for PCMCIA cdroms
 * Version 5.46		remove the mc68000 #ifdefs for 2.0.x
 * Version 5.47		fix set_tune race condition
 *			fix bug in earlier PCMCIA cdrom update
 * Version 5.48		if def'd, invoke CMD640_DUMP_REGS when irq probe fails
 *			lengthen the do_reset1() pulse, for laptops
 *			add idebus=xx parameter for cmd640 and ali chipsets
 *			no_unmask flag now per-drive instead of per-hwif
 *			fix tune_req so that it gets done immediately
 *			fix missing restore_flags() in ide_ioctl
 *			prevent use of io_32bit on cmd640 with no prefetch
 * Version 5.49		fix minor quirks in probing routines
 * 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 5.53		add ATAPI floppy drive support
 *			change default media for type 0 to floppy
 *			add support for Exabyte Nest
 *			add missing set_blocksize() in revalidate_disk()
 *			handle bad status bit sequencing in ide_wait_stat()
 *			support partition table translations with 255 heads
 *			probe all interfaces by default
 *			add probe for the i82371AB chipset
 *			acknowledge media change on removable drives
 *			add work-around for BMI drives
 *			remove "LBA" from boot messages
 * Version 5.53.1	add UDMA "CRC retry" support
 * Version 5.53.2	add Promise/33 auto-detection and DMA support
 *			fix MC_ERR handling
 *			fix mis-detection of NEC cdrom as floppy
 *			issue ATAPI reset and re-probe after "no response"
 *
 *  Some additional driver compile-time options are in ide.h
 *
 *  To do, in likely order of completion:
 *	- modify kernel to obtain BIOS geometry for drives on 2nd/3rd/4th i/f
*/

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

#include <linux/config.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/timer.h>
#include <linux/mm.h>
#include <linux/ioport.h>
#include <linux/interrupt.h>
#include <linux/major.h>
#include <linux/blkdev.h>
#include <linux/errno.h>
#include <linux/hdreg.h>
#include <linux/genhd.h>
#include <linux/malloc.h>

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

#ifdef CONFIG_PCI
#include <linux/bios32.h>
#include <linux/pci.h>
#endif /* CONFIG_PCI */

#include "ide.h"
#include "ide_modes.h"

#ifdef CONFIG_BLK_DEV_PROMISE
#include "promise.h"
#define IS_PROMISE_DRIVE (HWIF(drive)->chipset == ide_promise)
#else
#define IS_PROMISE_DRIVE (0)	/* auto-NULLs out Promise code */
#endif /* CONFIG_BLK_DEV_PROMISE */

static const byte	ide_hwif_to_major[MAX_HWIFS] = {IDE0_MAJOR, IDE1_MAJOR, IDE2_MAJOR, IDE3_MAJOR};
static const unsigned short default_io_base[MAX_HWIFS] = {0x1f0, 0x170, 0x1e8, 0x168};
static const byte	default_irqs[MAX_HWIFS]     = {14, 15, 11, 10};
static int	idebus_parameter; /* holds the "idebus=" parameter */
static int	system_bus_speed; /* holds what we think is VESA/PCI bus speed */

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

#if (DISK_RECOVERY_TIME > 0)
/*
 * For really screwy hardware (hey, at least it *can* be used with Linux)
 * we can enforce a minimum delay time between successive operations.
 */
static unsigned long read_timer(void)
{
	unsigned long t, flags;
	int i;

	save_flags(flags);
	cli();
	t = jiffies * 11932;
    	outb_p(0, 0x43);
	i = inb_p(0x40);
	i |= inb(0x40) << 8;
	restore_flags(flags);
	return (t - i);
}

static void set_recovery_timer (ide_hwif_t *hwif)
{
	hwif->last_time = read_timer();
}
#define SET_RECOVERY_TIMER(drive) set_recovery_timer (drive)

#else

#define SET_RECOVERY_TIMER(drive)

#endif /* DISK_RECOVERY_TIME */


/*
 * Do not even *think* about calling this!
 */
static void init_hwif_data (unsigned int index)
{
	byte *p;
	unsigned int unit;
	ide_hwif_t *hwif = &ide_hwifs[index];

	/* bulk initialize hwif & drive info with zeros */
	p = ((byte *) hwif) + sizeof(ide_hwif_t);
	do {
		*--p = 0;
	} while (p > (byte *) hwif);

	/* fill in any non-zero initial values */
	hwif->index     = index;
	hwif->io_base	= default_io_base[index];
	hwif->ctl_port	= hwif->io_base ? hwif->io_base+0x206 : 0x000;
#ifdef CONFIG_BLK_DEV_HD
	if (hwif->io_base == HD_DATA)
		hwif->noprobe = 1; /* may be overridden by ide_setup() */
#endif /* CONFIG_BLK_DEV_HD */
	hwif->major	= ide_hwif_to_major[index];
	hwif->name[0]	= 'i';
	hwif->name[1]	= 'd';
	hwif->name[2]	= 'e';
	hwif->name[3]	= '0' + index;
#ifdef CONFIG_BLK_DEV_IDETAPE
	hwif->tape_drive = NULL;