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