Documentation/kernel-parameters.txt

   1 February 2003             Kernel Parameters                     v2.5.59
   2                           ~~~~~~~~~~~~~~~~~
   3
   4 The following is a consolidated list of the kernel parameters as implemented
   5 (mostly) by the __setup() macro and sorted into English Dictionary order
   6 (defined as ignoring all punctuation and sorting digits before letters in a
   7 case insensitive manner), and with descriptions where known.
   8
   9 Module parameters for loadable modules are specified only as the
  10 parameter name with optional '=' and value as appropriate, such as:
  11
  12         modprobe usbcore blinkenlights=1
  13
  14 Module parameters for modules that are built into the kernel image
  15 are specified on the kernel command line with the module name plus
  16 '.' plus parameter name, with '=' and value if appropriate, such as:
  17
  18         usbcore.blinkenlights=1
  19
  20 The text in square brackets at the beginning of the description state the
  21 restrictions on the kernel for the said kernel parameter to be valid. The
  22 restrictions referred to are that the relevant option is valid if:
  23
  24         ACPI    ACPI support is enabled.
  25         ALSA    ALSA sound support is enabled.
  26         APIC    APIC support is enabled.
  27         APM     Advanced Power Management support is enabled.
  28         AX25    Appropriate AX.25 support is enabled.
  29         CD      Appropriate CD support is enabled.
  30         DEVFS   devfs support is enabled.
  31         DRM     Direct Rendering Management support is enabled.
  32         EDD     BIOS Enhanced Disk Drive Services (EDD) is enabled
  33         EFI     EFI Partitioning (GPT) is enabled
  34         EIDE    EIDE/ATAPI support is enabled.
  35         FB      The frame buffer device is enabled.
  36         HW      Appropriate hardware is enabled.
  37         IA-32   IA-32 aka i386 architecture is enabled.
  38         IA-64   IA-64 architecture is enabled.
  39         IOSCHED More than one I/O scheduler is enabled.
  40         IP_PNP  IP DCHP, BOOTP, or RARP is enabled.
  41         ISAPNP  ISA PnP code is enabled.
  42         ISDN    Appropriate ISDN support is enabled.
  43         JOY     Appropriate joystick support is enabled.
  44         LP      Printer support is enabled.
  45         LOOP    Loopback device support is enabled.
  46         M68k    M68k architecture is enabled.
  47                         These options have more detailed description inside of
  48                         Documentation/m68k/kernel-options.txt.
  49         MCA     MCA bus support is enabled.
  50         MDA     MDA console support is enabled.
  51         MOUSE   Appropriate mouse support is enabled.
  52         MTD     MTD support is enabled.
  53         NET     Appropriate network support is enabled.
  54         NFS     Appropriate NFS support is enabled.
  55         OSS     OSS sound support is enabled.
  56         PARIDE  The ParIDE subsystem is enabled.
  57         PARISC  The PA-RISC architecture is enabled.
  58         PCI     PCI bus support is enabled.
  59         PCMCIA  The PCMCIA subsystem is enabled.
  60         PNP     Plug & Play support is enabled.
  61         PPC     PowerPC architecture is enabled.
  62         PPT     Parallel port support is enabled.
  63         PS2     Appropriate PS/2 support is enabled.
  64         RAM     RAM disk support is enabled.
  65         S390    S390 architecture is enabled.
  66         SCSI    Appropriate SCSI support is enabled.
  67                         A lot of drivers has their options described inside of
  68                         Documentation/scsi/.
  69         SERIAL  Serial support is enabled.
  70         SMP     The kernel is an SMP kernel.
  71         SPARC   Sparc architecture is enabled.
  72         SWSUSP  Software suspension is enabled.
  73         TS      Appropriate touchscreen support is enabled.
  74         USB     USB support is enabled.
  75         V4L     Video For Linux support is enabled.
  76         VGA     The VGA console has been enabled.
  77         VT      Virtual terminal support is enabled.
  78         WDT     Watchdog support is enabled.
  79         XT      IBM PC/XT MFM hard disk support is enabled.
  80
  81 In addition, the following text indicates that the option:
  82
  83         BUGS=   Relates to possible processor bugs on the said processor.
  84         KNL     Is a kernel start-up parameter.
  85         BOOT    Is a boot loader parameter.
  86
  87 Parameters denoted with BOOT are actually interpreted by the boot
  88 loader, and have no meaning to the kernel directly.
  89 Do not modify the syntax of boot loader parameters without extreme
  90 need or coordination with <Documentation/i386/boot.txt>.
  91
  92 Note that ALL kernel parameters listed below are CASE SENSITIVE, and that
  93 a trailing = on the name of any parameter states that that parameter will
  94 be entered as an environment variable, whereas its absence indicates that
  95 it will appear as a kernel argument readable via /proc/cmdline by programs
  96 running once the system is up.
  97
  98         53c7xx=         [HW,SCSI] Amiga SCSI controllers
  99                         See header of drivers/scsi/53c7xx.c.
 100                         See also Documentation/scsi/ncr53c7xx.txt.
 101
 102         acpi=           [HW,ACPI] Advanced Configuration and Power Interface
 103                         Format: { force | off | ht | strict }
 104                         force -- enable ACPI if default was off
 105                         off -- disable ACPI if default was on
 106                         noirq -- do not use ACPI for IRQ routing
 107                         ht -- run only enough ACPI to enable Hyper Threading
 108                         strict --  Be less tolerant of platforms that are not
 109                                 strictly ACPI specification compliant.
 110
 111                         See also Documentation/pm.txt, pci=noacpi
 112
 113         acpi_sleep=     [HW,ACPI] Sleep options
 114                         Format: { s3_bios, s3_mode }
 115                         See Documentation/power/video.txt
 116
 117         acpi_sci=       [HW,ACPI] ACPI System Control Interrupt trigger mode
 118                         Format: { level | edge |  high | low }
 119
 120         acpi_irq_balance        [HW,ACPI] ACPI will balance active IRQs
 121                                 default in APIC mode
 122
 123         acpi_irq_nobalance      [HW,ACPI] ACPI will not move active IRQs (default)
 124                                 default in PIC mode
 125
 126         acpi_irq_pci=   [HW,ACPI] If irq_balance, Clear listed IRQs for use by PCI
 127                         Format: <irq>,<irq>...
 128
 129         acpi_irq_isa=   [HW,ACPI] If irq_balance, Mark listed IRQs used by ISA
 130                         Format: <irq>,<irq>...
 131
 132         acpi_osi=       [HW,ACPI] empty param disables _OSI
 133
 134         acpi_serialize  [HW,ACPI] force serialization of AML methods
 135
 136         acpi_skip_timer_override [HW,ACPI]
 137                         Recognize and ignore IRQ0/pin2 Interrupt Override.
 138                         For broken nForce2 BIOS resulting in XT-PIC timer.
 139
 140         acpi_dbg_layer= [HW,ACPI]
 141                         Format: <int>
 142                         Each bit of the <int> indicates an acpi debug layer,
 143                         1: enable, 0: disable. It is useful for boot time
 144                         debugging. After system has booted up, it can be set
 145                         via /proc/acpi/debug_layer.
 146
 147         acpi_dbg_level= [HW,ACPI]
 148                         Format: <int>
 149                         Each bit of the <int> indicates an acpi debug level,
 150                         1: enable, 0: disable. It is useful for boot time
 151                         debugging. After system has booted up, it can be set
 152                         via /proc/acpi/debug_level.
 153
 154         ad1816=         [HW,OSS]
 155                         Format: <io>,<irq>,<dma>,<dma2>
 156                         See also Documentation/sound/oss/AD1816.
 157
 158         ad1848=         [HW,OSS]
 159                         Format: <io>,<irq>,<dma>,<dma2>,<type>
 160
 161         adlib=          [HW,OSS]
 162                         Format: <io>
 163
 164         advansys=       [HW,SCSI]
 165                         See header of drivers/scsi/advansys.c.
 166
 167         advwdt=         [HW,WDT] Advantech WDT
 168                         Format: <iostart>,<iostop>
 169
 170         aedsp16=        [HW,OSS] Audio Excel DSP 16
 171                         Format: <io>,<irq>,<dma>,<mss_io>,<mpu_io>,<mpu_irq>
 172                         See also header of sound/oss/aedsp16.c.
 173
 174         aha152x=        [HW,SCSI]
 175                         See Documentation/scsi/aha152x.txt.
 176
 177         aha1542=        [HW,SCSI]
 178                         Format: <portbase>[,<buson>,<busoff>[,<dmaspeed>]]
 179
 180         aic7xxx=        [HW,SCSI]
 181                         See Documentation/scsi/aic7xxx.txt.
 182
 183         aic79xx=        [HW,SCSI]
 184                         See Documentation/scsi/aic79xx.txt.
 185
 186         AM53C974=       [HW,SCSI]
 187                         Format: <host-scsi-id>,<target-scsi-id>,<max-rate>,<max-offset>
 188                         See also header of drivers/scsi/AM53C974.c.
 189
 190         amijoy.map=     [HW,JOY] Amiga joystick support
 191                         Map of devices attached to JOY0DAT and JOY1DAT
 192                         Format: <a>,<b>
 193                         See also Documentation/kernel/input/joystick.txt
 194
 195         analog.map=     [HW,JOY] Analog joystick and gamepad support
 196                         Specifies type or capabilities of an analog joystick
 197                         connected to one of 16 gameports
 198                         Format: <type1>,<type2>,..<type16>
 199
 200         apc=            [HW,SPARC] Power management functions (SPARCstation-4/5 + deriv.)
 201                         Format: noidle
 202                         Disable APC CPU standby support. SPARCstation-Fox does
 203                         not play well with APC CPU idle - disable it if you have
 204                         APC and your system crashes randomly.
 205
 206         apic=           [APIC,i386] Change the output verbosity  whilst booting
 207                         Format: { quiet (default) | verbose | debug }
 208                         Change the amount of debugging information output
 209                         when initialising the APIC and IO-APIC components.
 210
 211         apm=            [APM] Advanced Power Management
 212                         See header of arch/i386/kernel/apm.c.
 213
 214         applicom=       [HW]
 215                         Format: <mem>,<irq>
 216
 217         arcrimi=        [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
 218                         Format: <io>,<irq>,<nodeID>
 219
 220         ataflop=        [HW,M68k]
 221
 222         atarimouse=     [HW,MOUSE] Atari Mouse
 223
 224         atascsi=        [HW,SCSI] Atari SCSI
 225
 226         atkbd.extra=    [HW] Enable extra LEDs and keys on IBM RapidAccess, EzKey
 227                         and similar keyboards
 228
 229         atkbd.reset=    [HW] Reset keyboard during initialization
 230
 231         atkbd.set=      [HW] Select keyboard code set
 232                         Format: <int> (2 = AT (default) 3 = PS/2)
 233
 234         atkbd.scroll=   [HW] Enable scroll wheel on MS Office and similar keyboards
 235
 236         atkbd.softrepeat=
 237                         [HW] Use software keyboard repeat
 238
 239         autotest        [IA64]
 240
 241         awe=            [HW,OSS] AWE32/SB32/AWE64 wave table synth
 242                         Format: <io>,<memsize>,<isapnp>
 243
 244         aztcd=          [HW,CD] Aztech CD268 CDROM driver
 245                         Format: <io>,0x79 (?)
 246
 247         baycom_epp=     [HW,AX25]
 248                         Format: <io>,<mode>
 249
 250         baycom_par=     [HW,AX25] BayCom Parallel Port AX.25 Modem
 251                         Format: <io>,<mode>
 252                         See header of drivers/net/hamradio/baycom_par.c.
 253
 254         baycom_ser_fdx= [HW,AX25] BayCom Serial Port AX.25 Modem (Full Duplex Mode)
 255                         Format: <io>,<irq>,<mode>[,<baud>]
 256                         See header of drivers/net/hamradio/baycom_ser_fdx.c.
 257
 258         baycom_ser_hdx= [HW,AX25] BayCom Serial Port AX.25 Modem (Half Duplex Mode)
 259                         Format: <io>,<irq>,<mode>
 260                         See header of drivers/net/hamradio/baycom_ser_hdx.c.
 261
 262         blkmtd_device=  [HW,MTD]
 263         blkmtd_erasesz=
 264         blkmtd_ro=
 265         blkmtd_bs=
 266         blkmtd_count=
 267
 268         bttv.card=      [HW,V4L] bttv (bt848 + bt878 based grabber cards)
 269         bttv.radio=     Most important insmod options are available as kernel args too.
 270         bttv.pll=       See Documentation/video4linux/bttv/Insmod-options
 271         bttv.tuner=     and Documentation/video4linux/bttv/CARDLIST
 272
 273         BusLogic=       [HW,SCSI]
 274                         See drivers/scsi/BusLogic.c, comment before function
 275                         BusLogic_ParseDriverOptions().
 276
 277         c101=           [NET] Moxa C101 synchronous serial card
 278
 279         cachesize=      [BUGS=IA-32] Override level 2 CPU cache size detection.
 280                         Sometimes CPU hardware bugs make them report the cache
 281                         size incorrectly. The kernel will attempt work arounds
 282                         to fix known problems, but for some CPUs it is not
 283                         possible to determine what the correct size should be.
 284                         This option provides an override for these situations.
 285
 286         cdu31a=         [HW,CD]
 287                         Format: <io>,<irq>[,PAS]
 288                         See header of drivers/cdrom/cdu31a.c.
 289
 290         chandev=        [HW,NET] Generic channel device initialisation
 291
 292         clock=          [BUGS=IA-32, HW] gettimeofday timesource override.
 293                         Forces specified timesource (if avaliable) to be used
 294                         when calculating gettimeofday(). If specicified timesource
 295                         is not avalible, it defaults to PIT.
 296                         Format: { pit | tsc | cyclone | pmtmr }
 297
 298         hpet=           [IA-32,HPET] option to disable HPET and use PIT.
 299                         Format: disable
 300
 301         cm206=          [HW,CD]
 302                         Format: { auto | [<io>,][<irq>] }
 303
 304         com20020=       [HW,NET] ARCnet - COM20020 chipset
 305                         Format: <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]]
 306
 307         com90io=        [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
 308                         Format: <io>[,<irq>]
 309
 310         com90xx=        [HW,NET] ARCnet - COM90xx chipset (memory-mapped buffers)
 311                         Format: <io>[,<irq>[,<memstart>]]
 312
 313         condev=         [HW,S390] console device
 314         conmode=
 315
 316         console=        [KNL] Output console device and options.
 317
 318                 tty<n>  Use the virtual console device <n>.
 319
 320                 ttyS<n>[,options]
 321                         Use the specified serial port.  The options are of
 322                         the form "bbbbpn", where "bbbb" is the baud rate,
 323                         "p" is parity ("n", "o", or "e"), and "n" is bits.
 324                         Default is "9600n8".
 325
 326                         See also Documentation/serial-console.txt.
 327
 328                 uart,io,<addr>[,options]
 329                 uart,mmio,<addr>[,options]
 330                         Start an early, polled-mode console on the 8250/16550
 331                         UART at the specified I/O port or MMIO address,
 332                         switching to the matching ttyS device later.  The
 333                         options are the same as for ttyS, above.
 334
 335         cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver
 336                         Format: <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
 337
 338         cpia_pp=        [HW,PPT]
 339                         Format: { parport<nr> | auto | none }
 340
 341         cs4232=         [HW,OSS]
 342                         Format: <io>,<irq>,<dma>,<dma2>,<mpuio>,<mpuirq>
 343
 344         cs89x0_dma=     [HW,NET]
 345                         Format: <dma>
 346
 347         cs89x0_media=   [HW,NET]
 348                         Format: { rj45 | aui | bnc }
 349
 350         cyclades=       [HW,SERIAL] Cyclades multi-serial port adapter.
 351
 352         dasd=           [HW,NET]
 353                         See header of drivers/s390/block/dasd_devmap.c.
 354
 355         db9.dev[2|3]=   [HW,JOY] Multisystem joystick support via parallel port
 356                         (one device per port)
 357                         Format: <port#>,<type>
 358                         See also Documentation/input/joystick-parport.txt
 359
 360         debug           [KNL] Enable kernel debugging (events log level).
 361
 362         decnet=         [HW,NET]
 363                         Format: <area>[,<node>]
 364                         See also Documentation/networking/decnet.txt.
 365
 366         devfs=          [DEVFS]
 367                         See Documentation/filesystems/devfs/boot-options.
 368
 369         dhash_entries=  [KNL]
 370                         Set number of hash buckets for dentry cache.
 371
 372         digi=           [HW,SERIAL]
 373                         IO parameters + enable/disable command.
 374
 375         digiepca=       [HW,SERIAL]
 376                         See drivers/char/README.epca and
 377                         Documentation/digiepca.txt.
 378
 379         dmascc=         [HW,AX25,SERIAL] AX.25 Z80SCC driver with DMA
 380                         support available.
 381                         Format: <io_dev0>[,<io_dev1>[,..<io_dev32>]]
 382
 383         dmasound=       [HW,OSS] Sound subsystem buffers
 384
 385         dscc4.setup=    [NET]
 386
 387         dtc3181e=       [HW,SCSI]
 388
 389         earlyprintk=    [x86, x86_64]
 390                         earlyprintk=vga
 391                         earlyprintk=serial[,ttySn[,baudrate]]
 392
 393                         Append ,keep to not disable it when the real console
 394                         takes over.
 395
 396                         Only vga or serial at a time, not both.
 397
 398                         Currently only ttyS0 and ttyS1 are supported.
 399
 400                         Interaction with the standard serial driver is not
 401                         very good.
 402
 403                         The VGA output is eventually overwritten by the real
 404                         console.
 405
 406         eata=           [HW,SCSI]
 407
 408         eda=            [HW,PS2]
 409
 410         edb=            [HW,PS2]
 411
 412         edd             [EDD]
 413                         Format: {"of[f]" | "sk[ipmbr]"}
 414                         See comment in arch/i386/boot/edd.S
 415
 416         eicon=          [HW,ISDN]
 417                         Format: <id>,<membase>,<irq>
 418
 419         eisa_irq_edge=  [PARISC,HW]
 420                         See header of drivers/parisc/eisa.c.
 421
 422         elanfreq=       [IA-32]
 423                         See comment before function elanfreq_setup() in
 424                         arch/i386/kernel/cpu/cpufreq/elanfreq.c.
 425
 426         elevator=       [IOSCHED]
 427                         Format: {"as"|"cfq"|"deadline"|"noop"}
 428                         See Documentation/block/as-iosched.txt
 429                         and Documentation/block/deadline-iosched.txt for details.
 430
 431         es1370=         [HW,OSS]
 432                         Format: <lineout>[,<micbias>]
 433                         See also header of sound/oss/es1370.c.
 434
 435         es1371=         [HW,OSS]
 436                         Format: <spdif>,[<nomix>,[<amplifier>]]
 437                         See also header of sound/oss/es1371.c.
 438
 439         ether=          [HW,NET] Ethernet cards parameters
 440                         This option is obsoleted by the "netdev=" option, which
 441                         has equivalent usage. See its documentation for details.
 442
 443         eurwdt=         [HW,WDT] Eurotech CPU-1220/1410 onboard watchdog.
 444                         Format: <io>[,<irq>]
 445
 446         fd_mcs=         [HW,SCSI]
 447                         See header of drivers/scsi/fd_mcs.c.
 448
 449         fdomain=        [HW,SCSI]
 450                         See header of drivers/scsi/fdomain.c.
 451
 452         floppy=         [HW]
 453                         See Documentation/floppy.txt.
 454
 455         ftape=          [HW] Floppy Tape subsystem debugging options.
 456                         See Documentation/ftape.txt.
 457
 458         gamecon.map[2|3]=
 459                         [HW,JOY] Multisystem joystick and NES/SNES/PSX pad
 460                         support via parallel port (up to 5 devices per port)
 461                         Format: <port#>,<pad1>,<pad2>,<pad3>,<pad4>,<pad5>
 462                         See also Documentation/input/joystick-parport.txt
 463
 464         gamma=          [HW,DRM]
 465
 466         gdth=           [HW,SCSI]
 467                         See header of drivers/scsi/gdth.c.
 468
 469         gpt             [EFI] Forces disk with valid GPT signature but
 470                         invalid Protective MBR to be treated as GPT.
 471
 472         gscd=           [HW,CD]
 473                         Format: <io>
 474
 475         gt96100eth=     [NET] MIPS GT96100 Advanced Communication Controller
 476
 477         gus=            [HW,OSS]
 478                         Format: <io>,<irq>,<dma>,<dma16>
 479
 480         gvp11=          [HW,SCSI]
 481
 482         hcl=            [IA-64] SGI's Hardware Graph compatibility layer
 483
 484         hd=             [EIDE] (E)IDE hard drive subsystem geometry
 485                         Format: <cyl>,<head>,<sect>
 486
 487         hd?=            [HW] (E)IDE subsystem
 488         hd?lun=         See Documentation/ide.txt.
 489
 490         highmem=nn[KMG] [KNL,BOOT] forces the highmem zone to have an exact
 491                         size of <nn>. This works even on boxes that have no
 492                         highmem otherwise. This also works to reduce highmem
 493                         size on bigger boxes.
 494
 495         hisax=          [HW,ISDN]
 496                         See Documentation/isdn/README.HiSax.
 497
 498         hugepages=      [HW,IA-32,IA-64] Maximal number of HugeTLB pages.
 499
 500         noirqbalance    [IA-32,SMP,KNL] Disable kernel irq balancing
 501
 502         i8042.direct    [HW] Put keyboard port into non-translated mode
 503         i8042.dumbkbd   [HW] Pretend that controlled can only read data from
 504                              keyboard and can not control its state
 505                              (Don't attempt to blink the leds)
 506         i8042.noaux     [HW] Don't check for auxiliary (== mouse) port
 507         i8042.nomux     [HW] Don't check presence of an active multiplexing
 508                              controller
 509         i8042.reset     [HW] Reset the controller during init and cleanup
 510         i8042.unlock    [HW] Unlock (ignore) the keylock
 511
 512         i810=           [HW,DRM]
 513
 514         i8k.force       [HW] Activate i8k driver even if SMM BIOS signature
 515                         does not match list of supported models.
 516         i8k.power_status
 517                         [HW] Report power status in /proc/i8k
 518                         (disabled by default)
 519         i8k.restricted  [HW] Allow controlling fans only if SYS_ADMIN
 520                         capability is set.
 521
 522         ibmmcascsi=     [HW,MCA,SCSI] IBM MicroChannel SCSI adapter
 523                         See Documentation/mca.txt.
 524
 525         icn=            [HW,ISDN]
 526                         Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]]
 527
 528         ide=            [HW] (E)IDE subsystem
 529                         Format: ide=nodma or ide=doubler or ide=reverse
 530                         See Documentation/ide.txt.
 531
 532         ide?=           [HW] (E)IDE subsystem
 533                         Format: ide?=noprobe or chipset specific parameters.
 534                         See Documentation/ide.txt.
 535
 536         idebus=         [HW] (E)IDE subsystem - VLB/PCI bus speed
 537                         See Documentation/ide.txt.
 538
 539         idle=           [HW]
 540                         Format: idle=poll or idle=halt
 541
 542         ihash_entries=  [KNL]
 543                         Set number of hash buckets for inode cache.
 544
 545         in2000=         [HW,SCSI]
 546                         See header of drivers/scsi/in2000.c.
 547
 548         init=           [KNL]
 549                         Format: <full_path>
 550                         Run specified binary instead of /sbin/init as init
 551                         process.
 552
 553         initcall_debug  [KNL] Trace initcalls as they are executed.  Useful
 554                         for working out where the kernel is dying during
 555                         startup.
 556
 557         initrd=         [BOOT] Specify the location of the initial ramdisk
 558
 559         inport.irq=     [HW] Inport (ATI XL and Microsoft) busmouse driver
 560                         Format: <irq>
 561
 562         inttest=        [IA64]
 563
 564         io7=            [HW] IO7 for Marvel based alpha systems
 565                         See comment before marvel_specify_io7 in
 566                         arch/alpha/kernel/core_marvel.c.
 567
 568         ip=             [IP_PNP]
 569                         See Documentation/nfsroot.txt.
 570
 571         ip2=            [HW] Set IO/IRQ pairs for up to 4 IntelliPort boards
 572                         See comment before ip2_setup() in drivers/char/ip2.c.
 573
 574         ips=            [HW,SCSI] Adaptec / IBM ServeRAID controller
 575                         See header of drivers/scsi/ips.c.
 576
 577         irqfixup        [HW]
 578                         When an interrupt is not handled search all handlers
 579                         for it. Intended to get systems with badly broken
 580                         firmware running.
 581
 582         irqpoll         [HW]
 583                         When an interrupt is not handled search all handlers
 584                         for it. Also check all handlers each timer
 585                         interrupt. Intended to get systems with badly broken
 586                         firmware running.
 587
 588         isapnp=         [ISAPNP]
 589                         Format: <RDP>, <reset>, <pci_scan>, <verbosity>
 590
 591         isolcpus=       [KNL,SMP] Isolate CPUs from the general scheduler.
 592                         Format: <cpu number>, ..., <cpu number>
 593                         This option can be used to specify one or more CPUs
 594                         to isolate from the general SMP balancing and scheduling
 595                         algorithms. The only way to move a process onto or off
 596                         an "isolated" CPU is via the CPU affinity syscalls.
 597
 598                         This option is the preferred way to isolate CPUs. The
 599                         alternative - manually setting the CPU mask of all tasks
 600                         in the system can cause problems and suboptimal load
 601                         balancer performance.
 602
 603         isp16=          [HW,CD]
 604                         Format: <io>,<irq>,<dma>,<setup>
 605
 606         iucv=           [HW,NET]
 607
 608         js=             [HW,JOY] Analog joystick
 609                         See Documentation/input/joystick.txt.
 610
 611         keepinitrd      [HW,ARM]
 612
 613         l2cr=           [PPC]
 614
 615         lapic           [IA-32,APIC] Enable the local APIC even if BIOS disabled it.
 616
 617         lasi=           [HW,SCSI] PARISC LASI driver for the 53c700 chip
 618                         Format: addr:<io>,irq:<irq>
 619
 620         llsc*=          [IA64]
 621                         See function print_params() in arch/ia64/sn/kernel/llsc4.c.
 622
 623         load_ramdisk=   [RAM] List of ramdisks to load from floppy
 624                         See Documentation/ramdisk.txt.
 625
 626         lockd.udpport=  [NFS]
 627
 628         lockd.tcpport=  [NFS]
 629
 630         logibm.irq=     [HW,MOUSE] Logitech Bus Mouse Driver
 631                         Format: <irq>
 632
 633         log_buf_len=n   Sets the size of the printk ring buffer, in bytes.
 634                         Format is n, nk, nM.  n must be a power of two.  The
 635                         default is set in kernel config.
 636
 637         lp=0            [LP]    Specify parallel ports to use, e.g,
 638         lp=port[,port...]       lp=none,parport0 (lp0 not configured, lp1 uses
 639         lp=reset                first parallel port). 'lp=0' disables the
 640         lp=auto                 printer driver. 'lp=reset' (which can be
 641                                 specified in addition to the ports) causes
 642                                 attached printers to be reset. Using
 643                                 lp=port1,port2,... specifies the parallel ports
 644                                 to associate lp devices with, starting with
 645                                 lp0. A port specification may be 'none' to skip
 646                                 that lp device, or a parport name such as
 647                                 'parport0'. Specifying 'lp=auto' instead of a
 648                                 port specification list means that device IDs
 649                                 from each port should be examined, to see if
 650                                 an IEEE 1284-compliant printer is attached; if
 651                                 so, the driver will manage that printer.
 652                                 See also header of drivers/char/lp.c.
 653
 654         lpj=n           [KNL]
 655                         Sets loops_per_jiffy to given constant, thus avoiding
 656                         time-consuming boot-time autodetection (up to 250 ms per
 657                         CPU). 0 enables autodetection (default). To determine
 658                         the correct value for your kernel, boot with normal
 659                         autodetection and see what value is printed. Note that
 660                         on SMP systems the preset will be applied to all CPUs,
 661                         which is likely to cause problems if your CPUs need
 662                         significantly divergent settings. An incorrect value
 663                         will cause delays in the kernel to be wrong, leading to
 664                         unpredictable I/O errors and other breakage. Although
 665                         unlikely, in the extreme case this might damage your
 666                         hardware.
 667
 668         ltpc=           [NET]
 669                         Format: <io>,<irq>,<dma>
 670
 671         mac5380=        [HW,SCSI]
 672                         Format: <can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
 673
 674         mac53c9x=       [HW,SCSI]
 675                         Format: <num_esps>,<disconnect>,<nosync>,<can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
 676
 677         mad16=          [HW,OSS]
 678                         Format: <io>,<irq>,<dma>,<dma16>,<mpu_io>,<mpu_irq>,<joystick>
 679
 680         maui=           [HW,OSS]
 681                         Format: <io>,<irq>
 682
 683         max_loop=       [LOOP] Maximum number of loopback devices that can
 684                         be mounted
 685                         Format: <1-256>
 686
 687         maxcpus=        [SMP] Maximum number of processors that an SMP kernel
 688                         should make use of
 689
 690         max_luns=       [SCSI] Maximum number of LUNs to probe
 691                         Should be between 1 and 2^32-1.
 692
 693         max_report_luns=
 694                         [SCSI] Maximum number of LUNs received
 695                         Should be between 1 and 16384.
 696
 697         mca-pentium     [BUGS=IA-32]
 698
 699         mcatest=        [IA-64]
 700
 701         mcd=            [HW,CD]
 702                         Format: <port>,<irq>,<mitsumi_bug_93_wait>
 703
 704         mcdx=           [HW,CD]
 705
 706         mce             [IA-32] Machine Check Exception
 707
 708         md=             [HW] RAID subsystems devices and level
 709                         See Documentation/md.txt.
 710
 711         mdacon=         [MDA]
 712                         Format: <first>,<last>
 713                         Specifies range of consoles to be captured by the MDA.
 714
 715         mem=nn[KMG]     [KNL,BOOT] Force usage of a specific amount of memory
 716                         Amount of memory to be used when the kernel is not able
 717                         to see the whole system memory or for test.
 718                         [IA-32] Use together with memmap= to avoid physical
 719                         address space collisions. Without memmap= PCI devices
 720                         could be placed at addresses belonging to unused RAM.
 721
 722         mem=nopentium   [BUGS=IA-32] Disable usage of 4MB pages for kernel
 723                         memory.
 724
 725         memmap=exactmap [KNL,IA-32] Enable setting of an exact
 726                         E820 memory map, as specified by the user.
 727                         Such memmap=exactmap lines can be constructed based on
 728                         BIOS output or other requirements. See the memmap=nn@ss
 729                         option description.
 730
 731         memmap=nn[KMG]@ss[KMG]
 732                         [KNL] Force usage of a specific region of memory
 733                         Region of memory to be used, from ss to ss+nn.
 734
 735         memmap=nn[KMG]#ss[KMG]
 736                         [KNL,ACPI] Mark specific memory as ACPI data.
 737                         Region of memory to be used, from ss to ss+nn.
 738
 739         memmap=nn[KMG]$ss[KMG]
 740                         [KNL,ACPI] Mark specific memory as reserved.
 741                         Region of memory to be used, from ss to ss+nn.
 742
 743         meye.*=         [HW] Set MotionEye Camera parameters
 744                         See Documentation/video4linux/meye.txt.
 745
 746         mga=            [HW,DRM]
 747
 748         mousedev.tap_time=
 749                         [MOUSE] Maximum time between finger touching and
 750                         leaving touchpad surface for touch to be considered
 751                         a tap and be reported as a left button click (for
 752                         touchpads working in absolute mode only).
 753                         Format: <msecs>
 754         mousedev.xres=  [MOUSE] Horizontal screen resolution, used for devices
 755                         reporting absolute coordinates, such as tablets
 756         mousedev.yres=  [MOUSE] Vertical screen resolution, used for devices
 757                         reporting absolute coordinates, such as tablets
 758
 759         mpu401=         [HW,OSS]
 760                         Format: <io>,<irq>
 761
 762         MTD_Partition=  [MTD]
 763                         Format: <name>,<region-number>,<size>,<offset>
 764
 765         MTD_Region=     [MTD]
 766                         Format: <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
 767
 768         mtdparts=       [MTD]
 769                         See drivers/mtd/cmdline.c.
 770
 771         n2=             [NET] SDL Inc. RISCom/N2 synchronous serial card
 772
 773         NCR_D700=       [HW,SCSI]
 774                         See header of drivers/scsi/NCR_D700.c.
 775
 776         ncr5380=        [HW,SCSI]
 777
 778         ncr53c400=      [HW,SCSI]
 779
 780         ncr53c400a=     [HW,SCSI]
 781
 782         ncr53c406a=     [HW,SCSI]
 783
 784         ncr53c8xx=      [HW,SCSI]
 785
 786         netdev=         [NET] Network devices parameters
 787                         Format: <irq>,<io>,<mem_start>,<mem_end>,<name>
 788                         Note that mem_start is often overloaded to mean
 789                         something different and driver-specific.
 790
 791         nfsaddrs=       [NFS]
 792                         See Documentation/nfsroot.txt.
 793
 794         nfsroot=        [NFS] nfs root filesystem for disk-less boxes.
 795                         See Documentation/nfsroot.txt.
 796
 797         nmi_watchdog=   [KNL,BUGS=IA-32] Debugging features for SMP kernels
 798
 799         no387           [BUGS=IA-32] Tells the kernel to use the 387 maths
 800                         emulation library even if a 387 maths coprocessor
 801                         is present.
 802
 803         noalign         [KNL,ARM]
 804
 805         noapic          [SMP,APIC] Tells the kernel to not make use of any
 806                         IOAPICs that may be present in the system.
 807
 808         noasync         [HW,M68K] Disables async and sync negotiation for
 809                         all devices.
 810
 811         nobats          [PPC] Do not use BATs for mapping kernel lowmem
 812                         on "Classic" PPC cores.
 813
 814         nocache         [ARM]
 815
 816         nodisconnect    [HW,SCSI,M68K] Disables SCSI disconnects.
 817
 818         noexec          [IA-64]
 819
 820         noexec          [i386, x86_64]
 821                         noexec=on: enable non-executable mappings (default)
 822                         noexec=off: disable nn-executable mappings
 823
 824         nofxsr          [BUGS=IA-32]
 825
 826         nohlt           [BUGS=ARM]
 827
 828         no-hlt          [BUGS=IA-32] Tells the kernel that the hlt
 829                         instruction doesn't work correctly and not to
 830                         use it.
 831
 832         noirqdebug      [IA-32] Disables the code which attempts to detect and
 833                         disable unhandled interrupt sources.
 834
 835         noisapnp        [ISAPNP] Disables ISA PnP code.
 836
 837         noinitrd        [RAM] Tells the kernel not to load any configured
 838                         initial RAM disk.
 839
 840         nointroute      [IA-64]
 841
 842         nolapic         [IA-32,APIC] Do not enable or use the local APIC.
 843
 844         noltlbs         [PPC] Do not use large page/tlb entries for kernel
 845                         lowmem mapping on PPC40x.
 846
 847         nomce           [IA-32] Machine Check Exception
 848
 849         noresidual      [PPC] Don't use residual data on PReP machines.
 850
 851         noresume        [SWSUSP] Disables resume and restore original swap space.
 852
 853         no-scroll       [VGA] Disables scrollback.
 854                         This is required for the Braillex ib80-piezo Braille
 855                         reader made by F.H. Papenmeier (Germany).
 856
 857         nosbagart       [IA-64]
 858
 859         nosmp           [SMP] Tells an SMP kernel to act as a UP kernel.
 860
 861         nosync          [HW,M68K] Disables sync negotiation for all devices.
 862
 863         notsc           [BUGS=IA-32] Disable Time Stamp Counter
 864
 865         nousb           [USB] Disable the USB subsystem
 866
 867         nowb            [ARM]
 868
 869         opl3=           [HW,OSS]
 870                         Format: <io>
 871
 872         opl3sa=         [HW,OSS]
 873                         Format: <io>,<irq>,<dma>,<dma2>,<mpu_io>,<mpu_irq>
 874
 875         opl3sa2=        [HW,OSS]
 876                         Format: <io>,<irq>,<dma>,<dma2>,<mss_io>,<mpu_io>,<ymode>,<loopback>[,<isapnp>,<multiple]
 877
 878         oprofile.timer= [HW]
 879                         Use timer interrupt instead of performance counters
 880
 881         optcd=          [HW,CD]
 882                         Format: <io>
 883
 884         osst=           [HW,SCSI] SCSI Tape Driver
 885                         Format: <buffer_size>,<write_threshold>
 886                         See also Documentation/scsi/st.txt.
 887
 888         panic=          [KNL] Kernel behaviour on panic
 889                         Format: <timeout>
 890
 891         parport=0       [HW,PPT]        Specify parallel ports. 0 disables.
 892         parport=auto                    Use 'auto' to force the driver to use
 893         parport=0xBBB[,IRQ[,DMA]]       any IRQ/DMA settings detected (the
 894                                         default is to ignore detected IRQ/DMA
 895                                         settings because of possible
 896                                         conflicts). You can specify the base
 897                                         address, IRQ, and DMA settings; IRQ and
 898                                         DMA should be numbers, or 'auto' (for
 899                                         using detected settings on that
 900                                         particular port), or 'nofifo' (to avoid
 901                                         using a FIFO even if it is detected).
 902                                         Parallel ports are assigned in the
 903                                         order they are specified on the command
 904                                         line, starting with parport0.
 905
 906         parport_init_mode=
 907                         [HW,PPT]        Configure VIA parallel port to
 908                                         operate in specific mode. This is
 909                                         necessary on Pegasos computer where
 910                                         firmware has no options for setting up
 911                                         parallel port mode and sets it to
 912                                         spp. Currently this function knows
 913                                         686a and 8231 chips.
 914                         Format: [spp|ps2|epp|ecp|ecpepp]
 915
 916         pas2=           [HW,OSS]
 917                         Format: <io>,<irq>,<dma>,<dma16>,<sb_io>,<sb_irq>,<sb_dma>,<sb_dma16>
 918
 919         pas16=          [HW,SCSI]
 920                         See header of drivers/scsi/pas16.c.
 921
 922         pcbit=          [HW,ISDN]
 923
 924         pcd.            [PARIDE]
 925                         See header of drivers/block/paride/pcd.c.
 926                         See also Documentation/paride.txt.
 927
 928         pci=option[,option...]          [PCI] various PCI subsystem options:
 929                 off                     [IA-32] don't probe for the PCI bus
 930                 bios                    [IA-32] force use of PCI BIOS, don't access
 931                                         the hardware directly. Use this if your machine
 932                                         has a non-standard PCI host bridge.
 933                 nobios                  [IA-32] disallow use of PCI BIOS, only direct
 934                                         hardware access methods are allowed. Use this
 935                                         if you experience crashes upon bootup and you
 936                                         suspect they are caused by the BIOS.
 937                 conf1                   [IA-32] Force use of PCI Configuration Mechanism 1.
 938                 conf2                   [IA-32] Force use of PCI Configuration Mechanism 2.
 939                 nosort                  [IA-32] Don't sort PCI devices according to
 940                                         order given by the PCI BIOS. This sorting is done
 941                                         to get a device order compatible with older kernels.
 942                 biosirq                 [IA-32] Use PCI BIOS calls to get the interrupt
 943                                         routing table. These calls are known to be buggy
 944                                         on several machines and they hang the machine when used,
 945                                         but on other computers it's the only way to get the
 946                                         interrupt routing table. Try this option if the kernel
 947                                         is unable to allocate IRQs or discover secondary PCI
 948                                         buses on your motherboard.
 949                 rom                     [IA-32] Assign address space to expansion ROMs.
 950                                         Use with caution as certain devices share address
 951                                         decoders between ROMs and other resources.
 952                 irqmask=0xMMMM          [IA-32] Set a bit mask of IRQs allowed to be assigned
 953                                         automatically to PCI devices. You can make the kernel
 954                                         exclude IRQs of your ISA cards this way.
 955                 lastbus=N               [IA-32] Scan all buses till bus #N. Can be useful
 956                                         if the kernel is unable to find your secondary buses
 957                                         and you want to tell it explicitly which ones they are.
 958                 assign-busses           [IA-32] Always assign all PCI bus
 959                                         numbers ourselves, overriding
 960                                         whatever the firmware may have
 961                                         done.
 962                 usepirqmask             [IA-32] Honor the possible IRQ mask
 963                                         stored in the BIOS $PIR table. This is
 964                                         needed on some systems with broken
 965                                         BIOSes, notably some HP Pavilion N5400
 966                                         and Omnibook XE3 notebooks. This will
 967                                         have no effect if ACPI IRQ routing is
 968                                         enabled.
 969                 noacpi                  [IA-32] Do not use ACPI for IRQ routing
 970                                         or for PCI scanning.
 971                 routeirq                Do IRQ routing for all PCI devices.
 972                                         This is normally done in pci_enable_device(),
 973                                         so this option is a temporary workaround
 974                                         for broken drivers that don't call it.
 975
 976                 firmware                [ARM] Do not re-enumerate the bus but
 977                                         instead just use the configuration
 978                                         from the bootloader. This is currently
 979                                         used on IXP2000 systems where the
 980                                         bus has to be configured a certain way
 981                                         for adjunct CPUs.
 982
 983         pcmv=           [HW,PCMCIA] BadgePAD 4
 984
 985         pd.             [PARIDE]
 986                         See Documentation/paride.txt.
 987
 988         pdcchassis=     [PARISC,HW] Disable/Enable PDC Chassis Status codes at
 989                         boot time.
 990                         Format: { 0 | 1 }
 991                         See arch/parisc/kernel/pdc_chassis.c
 992
 993         pf.             [PARIDE]
 994                         See Documentation/paride.txt.
 995
 996         pg.             [PARIDE]
 997                         See Documentation/paride.txt.
 998
 999         pirq=           [SMP,APIC] Manual mp-table setup
1000                         See Documentation/i386/IO-APIC.txt.
1001
1002         plip=           [PPT,NET] Parallel port network link
1003                         Format: { parport<nr> | timid | 0 }
1004                         See also Documentation/parport.txt.
1005
1006         pnpbios=        [ISAPNP]
1007                         { on | off | curr | res | no-curr | no-res }
1008
1009         pnp_reserve_irq=
1010                         [ISAPNP] Exclude IRQs for the autoconfiguration
1011
1012         pnp_reserve_dma=
1013                         [ISAPNP] Exclude DMAs for the autoconfiguration
1014
1015         pnp_reserve_io= [ISAPNP] Exclude I/O ports for the autoconfiguration
1016                         Ranges are in pairs (I/O port base and size).
1017
1018         pnp_reserve_mem=
1019                         [ISAPNP] Exclude memory regions for the autoconfiguration
1020                         Ranges are in pairs (memory base and size).
1021
1022         profile=        [KNL] Enable kernel profiling via /proc/profile
1023                         { schedule | <number> }
1024                         (param: schedule - profile schedule points}
1025                         (param: profile step/bucket size as a power of 2 for
1026                                 statistical time based profiling)
1027
1028         processor.max_cstate=   [HW, ACPI]
1029                         Limit processor to maximum C-state
1030                         max_cstate=9 overrides any DMI blacklist limit.
1031
1032         prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk
1033                         before loading.
1034                         See Documentation/ramdisk.txt.
1035
1036         psmouse.proto=  [HW,MOUSE] Highest PS2 mouse protocol extension to
1037                         probe for (bare|imps|exps).
1038         psmouse.rate=   [HW,MOUSE] Set desired mouse report rate, in reports
1039                         per second.
1040         psmouse.resetafter=
1041                         [HW,MOUSE] Try to reset the device after so many bad packets
1042                         (0 = never).
1043         psmouse.resolution=
1044                         [HW,MOUSE] Set desired mouse resolution, in dpi.
1045         psmouse.smartscroll=
1046                         [HW,MOUSE] Controls Logitech smartscroll autorepeat,
1047                         0 = disabled, 1 = enabled (default).
1048
1049         pss=            [HW,OSS] Personal Sound System (ECHO ESC614)
1050                         Format: <io>,<mss_io>,<mss_irq>,<mss_dma>,<mpu_io>,<mpu_irq>
1051
1052         pt.             [PARIDE]
1053                         See Documentation/paride.txt.
1054
1055         quiet=          [KNL] Disable log messages
1056
1057         r128=           [HW,DRM]
1058
1059         raid=           [HW,RAID]
1060                         See Documentation/md.txt.
1061
1062         ramdisk=        [RAM] Sizes of RAM disks in kilobytes [deprecated]
1063                         See Documentation/ramdisk.txt.
1064
1065         ramdisk_blocksize=
1066                         [RAM]
1067                         See Documentation/ramdisk.txt.
1068
1069         ramdisk_size=   [RAM] Sizes of RAM disks in kilobytes
1070                         New name for the ramdisk parameter.
1071                         See Documentation/ramdisk.txt.
1072
1073         reboot=         [BUGS=IA-32,BUGS=ARM,BUGS=IA-64] Rebooting mode
1074                         Format: <reboot_mode>[,<reboot_mode2>[,...]]
1075                         See arch/*/kernel/reboot.c.
1076
1077         reserve=        [KNL,BUGS] Force the kernel to ignore some iomem area
1078
1079         resume=         [SWSUSP] Specify the partition device for software suspension
1080
1081         rhash_entries=  [KNL,NET]
1082                         Set number of hash buckets for route cache
1083
1084         riscom8=        [HW,SERIAL]
1085                         Format: <io_board1>[,<io_board2>[,...<io_boardN>]]
1086
1087         ro              [KNL] Mount root device read-only on boot
1088
1089         root=           [KNL] Root filesystem
1090
1091         rootflags=      [KNL] Set root filesystem mount option string
1092
1093         rootfstype=     [KNL] Set root filesystem type
1094
1095         rw              [KNL] Mount root device read-write on boot
1096
1097         S               [KNL] Run init in single mode
1098
1099         sa1100ir        [NET]
1100                         See drivers/net/irda/sa1100_ir.c.
1101
1102         sb=             [HW,OSS]
1103                         Format: <io>,<irq>,<dma>,<dma2>
1104
1105         sbni=           [NET] Granch SBNI12 leased line adapter
1106
1107         sbpcd=          [HW,CD] Soundblaster CD adapter
1108                         Format: <io>,<type>
1109                         See a comment before function sbpcd_setup() in
1110                         drivers/cdrom/sbpcd.c.
1111
1112         sc1200wdt=      [HW,WDT] SC1200 WDT (watchdog) driver
1113                         Format: <io>[,<timeout>[,<isapnp>]]
1114
1115         scsi_debug_*=   [SCSI]
1116                         See drivers/scsi/scsi_debug.c.
1117
1118         scsi_default_dev_flags=
1119                         [SCSI] SCSI default device flags
1120                         Format: <integer>
1121
1122         scsi_dev_flags= [SCSI] Black/white list entry for vendor and model
1123                         Format: <vendor>:<model>:<flags>
1124                         (flags are integer value)
1125
1126         scsi_logging=   [SCSI]
1127
1128         serialnumber    [BUGS=IA-32]
1129
1130         sf16fm=         [HW] SF16FMI radio driver for Linux
1131                         Format: <io>
1132
1133         sg_def_reserved_size=
1134                         [SCSI]
1135
1136         sgalaxy=        [HW,OSS]
1137                         Format: <io>,<irq>,<dma>,<dma2>,<sgbase>
1138
1139         shapers=        [NET]
1140                         Maximal number of shapers.
1141
1142         sim710=         [SCSI,HW]
1143                         See header of drivers/scsi/sim710.c.
1144
1145         simeth=         [IA-64]
1146         simscsi=
1147
1148         sjcd=           [HW,CD]
1149                         Format: <io>,<irq>,<dma>
1150                         See header of drivers/cdrom/sjcd.c.
1151
1152         slram=          [HW,MTD]
1153
1154         smart2=         [HW]
1155                         Format: <io1>[,<io2>[,...,<io8>]]
1156
1157         snd-ad1816a=    [HW,ALSA]
1158
1159         snd-ad1848=     [HW,ALSA]
1160
1161         snd-ali5451=    [HW,ALSA]
1162
1163         snd-als100=     [HW,ALSA]
1164
1165         snd-als4000=    [HW,ALSA]
1166
1167         snd-azt2320=    [HW,ALSA]
1168
1169         snd-cmi8330=    [HW,ALSA]
1170
1171         snd-cmipci=     [HW,ALSA]
1172
1173         snd-cs4231=     [HW,ALSA]
1174
1175         snd-cs4232=     [HW,ALSA]
1176
1177         snd-cs4236=     [HW,ALSA]
1178
1179         snd-cs4281=     [HW,ALSA]
1180
1181         snd-cs46xx=     [HW,ALSA]
1182
1183         snd-dt019x=     [HW,ALSA]
1184
1185         snd-dummy=      [HW,ALSA]
1186
1187         snd-emu10k1=    [HW,ALSA]
1188
1189         snd-ens1370=    [HW,ALSA]
1190
1191         snd-ens1371=    [HW,ALSA]
1192
1193         snd-es968=      [HW,ALSA]
1194
1195         snd-es1688=     [HW,ALSA]
1196
1197         snd-es18xx=     [HW,ALSA]
1198
1199         snd-es1938=     [HW,ALSA]
1200
1201         snd-es1968=     [HW,ALSA]
1202
1203         snd-fm801=      [HW,ALSA]
1204
1205         snd-gusclassic= [HW,ALSA]
1206
1207         snd-gusextreme= [HW,ALSA]
1208
1209         snd-gusmax=     [HW,ALSA]
1210
1211         snd-hdsp=       [HW,ALSA]
1212
1213         snd-ice1712=    [HW,ALSA]
1214
1215         snd-intel8x0=   [HW,ALSA]
1216
1217         snd-interwave=  [HW,ALSA]
1218
1219         snd-interwave-stb=
1220                         [HW,ALSA]
1221
1222         snd-korg1212=   [HW,ALSA]
1223
1224         snd-maestro3=   [HW,ALSA]
1225
1226         snd-mpu401=     [HW,ALSA]
1227
1228         snd-mtpav=      [HW,ALSA]
1229
1230         snd-nm256=      [HW,ALSA]
1231
1232         snd-opl3sa2=    [HW,ALSA]
1233
1234         snd-opti92x-ad1848=
1235                         [HW,ALSA]
1236
1237         snd-opti92x-cs4231=
1238                         [HW,ALSA]
1239
1240         snd-opti93x=    [HW,ALSA]
1241
1242         snd-pmac=       [HW,ALSA]
1243
1244         snd-rme32=      [HW,ALSA]
1245
1246         snd-rme96=      [HW,ALSA]
1247
1248         snd-rme9652=    [HW,ALSA]
1249
1250         snd-sb8=        [HW,ALSA]
1251
1252         snd-sb16=       [HW,ALSA]
1253
1254         snd-sbawe=      [HW,ALSA]
1255
1256         snd-serial=     [HW,ALSA]
1257
1258         snd-sgalaxy=    [HW,ALSA]
1259
1260         snd-sonicvibes= [HW,ALSA]
1261
1262         snd-sun-amd7930=
1263                         [HW,ALSA]
1264
1265         snd-sun-cs4231= [HW,ALSA]
1266
1267         snd-trident=    [HW,ALSA]
1268
1269         snd-usb-audio=  [HW,ALSA,USB]
1270
1271         snd-via82xx=    [HW,ALSA]
1272
1273         snd-virmidi=    [HW,ALSA]
1274
1275         snd-wavefront=  [HW,ALSA]
1276
1277         snd-ymfpci=     [HW,ALSA]
1278
1279         sonicvibes=     [HW,OSS]
1280                         Format: <reverb>
1281
1282         sonycd535=      [HW,CD]
1283                         Format: <io>[,<irq>]
1284
1285         sonypi.*=       [HW] Sony Programmable I/O Control Device driver
1286                         See Documentation/sonypi.txt
1287
1288         specialix=      [HW,SERIAL] Specialix multi-serial port adapter
1289                         See Documentation/specialix.txt.
1290
1291         spia_io_base=   [HW,MTD]
1292         spia_fio_base=
1293         spia_pedr=
1294         spia_peddr=
1295
1296         sscape=         [HW,OSS]
1297                         Format: <io>,<irq>,<dma>,<mpu_io>,<mpu_irq>
1298
1299         st=             [HW,SCSI] SCSI tape parameters (buffers, etc.)
1300                         See Documentation/scsi/st.txt.
1301
1302         st0x=           [HW,SCSI]
1303                         See header of drivers/scsi/seagate.c.
1304
1305         sti=            [PARISC,HW]
1306                         Format: <num>
1307                         Set the STI (builtin display/keyboard on the HP-PARISC
1308                         machines) console (graphic card) which should be used
1309                         as the initial boot-console.
1310                         See also comment in drivers/video/console/sticore.c.
1311
1312         sti_font=       [HW]
1313                         See comment in drivers/video/console/sticore.c.
1314
1315         stifb=          [HW]
1316                         Format: bpp:<bpp1>[:<bpp2>[:<bpp3>...]]
1317
1318         stram_swap=     [HW,M68k]
1319
1320         swiotlb=        [IA-64] Number of I/O TLB slabs
1321
1322         switches=       [HW,M68k]
1323
1324         sym53c416=      [HW,SCSI]
1325                         See header of drivers/scsi/sym53c416.c.
1326
1327         sym53c8xx=      [HW,SCSI]
1328                         See Documentation/scsi/ncr53c8xx.txt.
1329
1330         t128=           [HW,SCSI]
1331                         See header of drivers/scsi/t128.c.
1332
1333         tdfx=           [HW,DRM]
1334
1335         thash_entries=  [KNL,NET]
1336                         Set number of hash buckets for TCP connection
1337
1338         tipar=          [HW]
1339                         See header of drivers/char/tipar.c.
1340
1341         tiusb=          [HW,USB] Texas Instruments' USB GraphLink (aka SilverLink)
1342                         Format: <timeout>
1343
1344         tmc8xx=         [HW,SCSI]
1345                         See header of drivers/scsi/seagate.c.
1346
1347         tmscsim=        [HW,SCSI]
1348                         See comment before function dc390_setup() in
1349                         drivers/scsi/tmscsim.c.
1350
1351         tp720=          [HW,PS2]
1352
1353         trix=           [HW,OSS] MediaTrix AudioTrix Pro
1354                         Format: <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq>
1355
1356         tsdev.xres=     [TS] Horizontal screen resolution.
1357         tsdev.yres=     [TS] Vertical screen resolution.
1358
1359         turbografx.map[2|3]=
1360                         [HW,JOY] TurboGraFX parallel port interface
1361                         Format: <port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7>
1362                         See also Documentation/input/joystick-parport.txt
1363
1364         u14-34f=        [HW,SCSI] UltraStor 14F/34F SCSI host adapter
1365                         See header of drivers/scsi/u14-34f.c.
1366
1367         uart401=        [HW,OSS]
1368                         Format: <io>,<irq>
1369
1370         uart6850=       [HW,OSS]
1371                         Format: <io>,<irq>
1372
1373         usb-handoff     [HW] Enable early USB BIOS -> OS handoff
1374
1375         video=          [FB] Frame buffer configuration
1376                         See Documentation/fb/modedb.txt.
1377
1378         vga=            [BOOT,IA-32] Select a particular video mode
1379                         See Documentation/i386/boot.txt and Documentation/svga.txt.
1380                         Use vga=ask for menu.
1381                         This is actually a boot loader parameter; the value is
1382                         passed to the kernel using a special protocol.
1383
1384         vmalloc=nn[KMG] [KNL,BOOT] forces the vmalloc area to have an exact
1385                         size of <nn>. This can be used to increase the
1386                         minimum size (128MB on x86). It can also be used to
1387                         decrease the size and leave more room for directly
1388                         mapped kernel RAM.
1389
1390         vmhalt=         [KNL,S390]
1391
1392         vmpoff=         [KNL,S390]
1393
1394         waveartist=     [HW,OSS]
1395                         Format: <io>,<irq>,<dma>,<dma2>
1396
1397         wd33c93=        [HW,SCSI]
1398                         See header of drivers/scsi/wd33c93.c.
1399
1400         wd7000=         [HW,SCSI]
1401                         See header of drivers/scsi/wd7000.c.
1402
1403         wdt=            [WDT] Watchdog
1404                         See Documentation/watchdog/watchdog.txt.
1405
1406         xd=             [HW,XT] Original XT pre-IDE (RLL encoded) disks.
1407         xd_geo=         See header of drivers/block/xd.c.
1408
1409         xirc2ps_cs=     [NET,PCMCIA]
1410                         Format: <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
1411
1412
1413
1414 Changelog:
1415
1416         The last known update (for 2.4.0) - the changelog was not kept before.
1417         2000-06-??      Mr. Unknown
1418
1419         Update for 2.5.49, description for most of the options introduced,
1420         references to other documentation (C files, READMEs, ..), added S390,
1421         PPC, SPARC, MTD, ALSA and OSS category. Minor corrections and
1422         reformatting.
1423         2002-11-24      Petr Baudis <pasky@ucw.cz>
1424                         Randy Dunlap <randy.dunlap@verizon.net>
1425
1426 TODO:
1427
1428         Add documentation for ALSA options.
1429         Add more DRM drivers.