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Linus Torvalds1da177e2005-04-16 15:20:36 -07001February 2003 Kernel Parameters v2.5.59
2 ~~~~~~~~~~~~~~~~~
3
4The 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
7case insensitive manner), and with descriptions where known.
8
9Module parameters for loadable modules are specified only as the
10parameter name with optional '=' and value as appropriate, such as:
11
12 modprobe usbcore blinkenlights=1
13
14Module parameters for modules that are built into the kernel image
15are 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
20The text in square brackets at the beginning of the description state the
21restrictions on the kernel for the said kernel parameter to be valid. The
22restrictions 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.
Adrian Bunk41e2e8b2005-07-12 13:58:33 -070040 IP_PNP IP DHCP, BOOTP, or RARP is enabled.
Linus Torvalds1da177e2005-04-16 15:20:36 -070041 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 NUMA NUMA support is enabled.
55 NFS Appropriate NFS support is enabled.
56 OSS OSS sound support is enabled.
57 PARIDE The ParIDE subsystem is enabled.
58 PARISC The PA-RISC architecture is enabled.
59 PCI PCI bus support is enabled.
60 PCMCIA The PCMCIA subsystem is enabled.
61 PNP Plug & Play support is enabled.
62 PPC PowerPC architecture is enabled.
63 PPT Parallel port support is enabled.
64 PS2 Appropriate PS/2 support is enabled.
65 RAM RAM disk support is enabled.
66 S390 S390 architecture is enabled.
67 SCSI Appropriate SCSI support is enabled.
68 A lot of drivers has their options described inside of
69 Documentation/scsi/.
70 SELINUX SELinux support is enabled.
71 SERIAL Serial support is enabled.
72 SMP The kernel is an SMP kernel.
73 SPARC Sparc architecture is enabled.
74 SWSUSP Software suspension is enabled.
75 TS Appropriate touchscreen support is enabled.
76 USB USB support is enabled.
77 USBHID USB Human Interface Device support is enabled.
78 V4L Video For Linux support is enabled.
79 VGA The VGA console has been enabled.
80 VT Virtual terminal support is enabled.
81 WDT Watchdog support is enabled.
82 XT IBM PC/XT MFM hard disk support is enabled.
83 X86-64 X86-64 architecture is enabled.
84 More X86-64 boot options can be found in
85 Documentation/x86_64/boot-options.txt .
86
87In addition, the following text indicates that the option:
88
89 BUGS= Relates to possible processor bugs on the said processor.
90 KNL Is a kernel start-up parameter.
91 BOOT Is a boot loader parameter.
92
93Parameters denoted with BOOT are actually interpreted by the boot
94loader, and have no meaning to the kernel directly.
95Do not modify the syntax of boot loader parameters without extreme
96need or coordination with <Documentation/i386/boot.txt>.
97
98Note that ALL kernel parameters listed below are CASE SENSITIVE, and that
99a trailing = on the name of any parameter states that that parameter will
100be entered as an environment variable, whereas its absence indicates that
101it will appear as a kernel argument readable via /proc/cmdline by programs
102running once the system is up.
103
104 53c7xx= [HW,SCSI] Amiga SCSI controllers
105 See header of drivers/scsi/53c7xx.c.
106 See also Documentation/scsi/ncr53c7xx.txt.
107
108 acpi= [HW,ACPI] Advanced Configuration and Power Interface
109 Format: { force | off | ht | strict }
110 force -- enable ACPI if default was off
111 off -- disable ACPI if default was on
112 noirq -- do not use ACPI for IRQ routing
113 ht -- run only enough ACPI to enable Hyper Threading
114 strict -- Be less tolerant of platforms that are not
115 strictly ACPI specification compliant.
116
117 See also Documentation/pm.txt, pci=noacpi
118
119 acpi_sleep= [HW,ACPI] Sleep options
120 Format: { s3_bios, s3_mode }
121 See Documentation/power/video.txt
122
123 acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
124 Format: { level | edge | high | low }
125
126 acpi_irq_balance [HW,ACPI] ACPI will balance active IRQs
127 default in APIC mode
128
129 acpi_irq_nobalance [HW,ACPI] ACPI will not move active IRQs (default)
130 default in PIC mode
131
132 acpi_irq_pci= [HW,ACPI] If irq_balance, Clear listed IRQs for use by PCI
133 Format: <irq>,<irq>...
134
135 acpi_irq_isa= [HW,ACPI] If irq_balance, Mark listed IRQs used by ISA
136 Format: <irq>,<irq>...
137
138 acpi_osi= [HW,ACPI] empty param disables _OSI
139
140 acpi_serialize [HW,ACPI] force serialization of AML methods
141
142 acpi_skip_timer_override [HW,ACPI]
143 Recognize and ignore IRQ0/pin2 Interrupt Override.
144 For broken nForce2 BIOS resulting in XT-PIC timer.
145
146 acpi_dbg_layer= [HW,ACPI]
147 Format: <int>
148 Each bit of the <int> indicates an acpi debug layer,
149 1: enable, 0: disable. It is useful for boot time
150 debugging. After system has booted up, it can be set
151 via /proc/acpi/debug_layer.
152
153 acpi_dbg_level= [HW,ACPI]
154 Format: <int>
155 Each bit of the <int> indicates an acpi debug level,
156 1: enable, 0: disable. It is useful for boot time
157 debugging. After system has booted up, it can be set
158 via /proc/acpi/debug_level.
159
160 acpi_fake_ecdt [HW,ACPI] Workaround failure due to BIOS lacking ECDT
161
Luming Yu30e332f2005-08-12 00:31:00 -0400162 acpi_generic_hotkey [HW,ACPI]
163 Allow consolidated generic hotkey driver to
164 over-ride platform specific driver.
165 See also Documentation/acpi-hotkey.txt.
166
Chuck Ebbert66759a02005-09-12 18:49:25 +0200167 enable_timer_pin_1 [i386,x86-64]
168 Enable PIN 1 of APIC timer
169 Can be useful to work around chipset bugs (in particular on some ATI chipsets)
170 The kernel tries to set a reasonable default.
171
172 disable_timer_pin_1 [i386,x86-64]
173 Disable PIN 1 of APIC timer
174 Can be useful to work around chipset bugs.
175
Linus Torvalds1da177e2005-04-16 15:20:36 -0700176 ad1816= [HW,OSS]
177 Format: <io>,<irq>,<dma>,<dma2>
178 See also Documentation/sound/oss/AD1816.
179
180 ad1848= [HW,OSS]
181 Format: <io>,<irq>,<dma>,<dma2>,<type>
182
183 adlib= [HW,OSS]
184 Format: <io>
185
186 advansys= [HW,SCSI]
187 See header of drivers/scsi/advansys.c.
188
189 advwdt= [HW,WDT] Advantech WDT
190 Format: <iostart>,<iostop>
191
192 aedsp16= [HW,OSS] Audio Excel DSP 16
193 Format: <io>,<irq>,<dma>,<mss_io>,<mpu_io>,<mpu_irq>
194 See also header of sound/oss/aedsp16.c.
195
196 aha152x= [HW,SCSI]
197 See Documentation/scsi/aha152x.txt.
198
199 aha1542= [HW,SCSI]
200 Format: <portbase>[,<buson>,<busoff>[,<dmaspeed>]]
201
202 aic7xxx= [HW,SCSI]
203 See Documentation/scsi/aic7xxx.txt.
204
205 aic79xx= [HW,SCSI]
206 See Documentation/scsi/aic79xx.txt.
207
208 AM53C974= [HW,SCSI]
209 Format: <host-scsi-id>,<target-scsi-id>,<max-rate>,<max-offset>
210 See also header of drivers/scsi/AM53C974.c.
211
212 amijoy.map= [HW,JOY] Amiga joystick support
213 Map of devices attached to JOY0DAT and JOY1DAT
214 Format: <a>,<b>
215 See also Documentation/kernel/input/joystick.txt
216
217 analog.map= [HW,JOY] Analog joystick and gamepad support
218 Specifies type or capabilities of an analog joystick
219 connected to one of 16 gameports
220 Format: <type1>,<type2>,..<type16>
221
222 apc= [HW,SPARC] Power management functions (SPARCstation-4/5 + deriv.)
223 Format: noidle
224 Disable APC CPU standby support. SPARCstation-Fox does
225 not play well with APC CPU idle - disable it if you have
226 APC and your system crashes randomly.
227
228 apic= [APIC,i386] Change the output verbosity whilst booting
229 Format: { quiet (default) | verbose | debug }
230 Change the amount of debugging information output
231 when initialising the APIC and IO-APIC components.
232
233 apm= [APM] Advanced Power Management
234 See header of arch/i386/kernel/apm.c.
235
236 applicom= [HW]
237 Format: <mem>,<irq>
238
239 arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
240 Format: <io>,<irq>,<nodeID>
241
242 ataflop= [HW,M68k]
243
244 atarimouse= [HW,MOUSE] Atari Mouse
245
246 atascsi= [HW,SCSI] Atari SCSI
247
248 atkbd.extra= [HW] Enable extra LEDs and keys on IBM RapidAccess,
249 EzKey and similar keyboards
250
251 atkbd.reset= [HW] Reset keyboard during initialization
252
253 atkbd.set= [HW] Select keyboard code set
254 Format: <int> (2 = AT (default) 3 = PS/2)
255
256 atkbd.scroll= [HW] Enable scroll wheel on MS Office and similar
257 keyboards
258
259 atkbd.softraw= [HW] Choose between synthetic and real raw mode
260 Format: <bool> (0 = real, 1 = synthetic (default))
261
262 atkbd.softrepeat=
263 [HW] Use software keyboard repeat
264
265 autotest [IA64]
266
267 awe= [HW,OSS] AWE32/SB32/AWE64 wave table synth
268 Format: <io>,<memsize>,<isapnp>
269
270 aztcd= [HW,CD] Aztech CD268 CDROM driver
271 Format: <io>,0x79 (?)
272
273 baycom_epp= [HW,AX25]
274 Format: <io>,<mode>
275
276 baycom_par= [HW,AX25] BayCom Parallel Port AX.25 Modem
277 Format: <io>,<mode>
278 See header of drivers/net/hamradio/baycom_par.c.
279
280 baycom_ser_fdx= [HW,AX25] BayCom Serial Port AX.25 Modem (Full Duplex Mode)
281 Format: <io>,<irq>,<mode>[,<baud>]
282 See header of drivers/net/hamradio/baycom_ser_fdx.c.
283
284 baycom_ser_hdx= [HW,AX25] BayCom Serial Port AX.25 Modem (Half Duplex Mode)
285 Format: <io>,<irq>,<mode>
286 See header of drivers/net/hamradio/baycom_ser_hdx.c.
287
288 blkmtd_device= [HW,MTD]
289 blkmtd_erasesz=
290 blkmtd_ro=
291 blkmtd_bs=
292 blkmtd_count=
293
294 bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards)
295 bttv.radio= Most important insmod options are available as kernel args too.
296 bttv.pll= See Documentation/video4linux/bttv/Insmod-options
297 bttv.tuner= and Documentation/video4linux/bttv/CARDLIST
298
299 BusLogic= [HW,SCSI]
300 See drivers/scsi/BusLogic.c, comment before function
301 BusLogic_ParseDriverOptions().
302
303 c101= [NET] Moxa C101 synchronous serial card
304
305 cachesize= [BUGS=IA-32] Override level 2 CPU cache size detection.
306 Sometimes CPU hardware bugs make them report the cache
307 size incorrectly. The kernel will attempt work arounds
308 to fix known problems, but for some CPUs it is not
309 possible to determine what the correct size should be.
310 This option provides an override for these situations.
311
312 cdu31a= [HW,CD]
313 Format: <io>,<irq>[,PAS]
314 See header of drivers/cdrom/cdu31a.c.
315
316 chandev= [HW,NET] Generic channel device initialisation
317
318 checkreqprot [SELINUX] Set initial checkreqprot flag value.
319 Format: { "0" | "1" }
320 See security/selinux/Kconfig help text.
321 0 -- check protection applied by kernel (includes any implied execute protection).
322 1 -- check protection requested by application.
323 Default value is set via a kernel config option.
324 Value can be changed at runtime via /selinux/checkreqprot.
325
326 clock= [BUGS=IA-32, HW] gettimeofday timesource override.
327 Forces specified timesource (if avaliable) to be used
328 when calculating gettimeofday(). If specicified timesource
329 is not avalible, it defaults to PIT.
330 Format: { pit | tsc | cyclone | pmtmr }
331
332 hpet= [IA-32,HPET] option to disable HPET and use PIT.
333 Format: disable
334
335 cm206= [HW,CD]
336 Format: { auto | [<io>,][<irq>] }
337
338 com20020= [HW,NET] ARCnet - COM20020 chipset
339 Format: <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]]
340
341 com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
342 Format: <io>[,<irq>]
343
344 com90xx= [HW,NET] ARCnet - COM90xx chipset (memory-mapped buffers)
345 Format: <io>[,<irq>[,<memstart>]]
346
347 condev= [HW,S390] console device
348 conmode=
349
350 console= [KNL] Output console device and options.
351
352 tty<n> Use the virtual console device <n>.
353
354 ttyS<n>[,options]
355 Use the specified serial port. The options are of
356 the form "bbbbpn", where "bbbb" is the baud rate,
357 "p" is parity ("n", "o", or "e"), and "n" is bits.
358 Default is "9600n8".
359
360 See also Documentation/serial-console.txt.
361
362 uart,io,<addr>[,options]
363 uart,mmio,<addr>[,options]
364 Start an early, polled-mode console on the 8250/16550
365 UART at the specified I/O port or MMIO address,
366 switching to the matching ttyS device later. The
367 options are the same as for ttyS, above.
368
369 cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver
370 Format: <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
371
372 cpia_pp= [HW,PPT]
373 Format: { parport<nr> | auto | none }
374
Eric W. Biedermandc009d92005-06-25 14:57:52 -0700375 crashkernel=nn[KMG]@ss[KMG]
376 [KNL] Reserve a chunk of physical memory to
377 hold a kernel to switch to with kexec on panic.
378
Linus Torvalds1da177e2005-04-16 15:20:36 -0700379 cs4232= [HW,OSS]
380 Format: <io>,<irq>,<dma>,<dma2>,<mpuio>,<mpuirq>
381
382 cs89x0_dma= [HW,NET]
383 Format: <dma>
384
385 cs89x0_media= [HW,NET]
386 Format: { rj45 | aui | bnc }
387
388 cyclades= [HW,SERIAL] Cyclades multi-serial port adapter.
389
390 dasd= [HW,NET]
391 See header of drivers/s390/block/dasd_devmap.c.
392
393 db9.dev[2|3]= [HW,JOY] Multisystem joystick support via parallel port
394 (one device per port)
395 Format: <port#>,<type>
396 See also Documentation/input/joystick-parport.txt
397
398 debug [KNL] Enable kernel debugging (events log level).
399
400 decnet= [HW,NET]
401 Format: <area>[,<node>]
402 See also Documentation/networking/decnet.txt.
403
404 devfs= [DEVFS]
405 See Documentation/filesystems/devfs/boot-options.
406
407 dhash_entries= [KNL]
408 Set number of hash buckets for dentry cache.
409
410 digi= [HW,SERIAL]
411 IO parameters + enable/disable command.
412
413 digiepca= [HW,SERIAL]
414 See drivers/char/README.epca and
415 Documentation/digiepca.txt.
416
417 dmascc= [HW,AX25,SERIAL] AX.25 Z80SCC driver with DMA
418 support available.
419 Format: <io_dev0>[,<io_dev1>[,..<io_dev32>]]
420
421 dmasound= [HW,OSS] Sound subsystem buffers
422
423 dscc4.setup= [NET]
424
425 dtc3181e= [HW,SCSI]
426
427 earlyprintk= [IA-32, X86-64]
428 earlyprintk=vga
429 earlyprintk=serial[,ttySn[,baudrate]]
430
431 Append ,keep to not disable it when the real console
432 takes over.
433
434 Only vga or serial at a time, not both.
435
436 Currently only ttyS0 and ttyS1 are supported.
437
438 Interaction with the standard serial driver is not
439 very good.
440
441 The VGA output is eventually overwritten by the real
442 console.
443
444 eata= [HW,SCSI]
445
446 eda= [HW,PS2]
447
448 edb= [HW,PS2]
449
450 edd= [EDD]
451 Format: {"of[f]" | "sk[ipmbr]"}
452 See comment in arch/i386/boot/edd.S
453
454 eicon= [HW,ISDN]
455 Format: <id>,<membase>,<irq>
456
457 eisa_irq_edge= [PARISC,HW]
458 See header of drivers/parisc/eisa.c.
459
460 elanfreq= [IA-32]
461 See comment before function elanfreq_setup() in
462 arch/i386/kernel/cpu/cpufreq/elanfreq.c.
463
464 elevator= [IOSCHED]
465 Format: {"as"|"cfq"|"deadline"|"noop"}
466 See Documentation/block/as-iosched.txt
467 and Documentation/block/deadline-iosched.txt for details.
Vivek Goyal2030eae2005-06-25 14:58:20 -0700468 elfcorehdr= [IA-32]
469 Specifies physical address of start of kernel core image
470 elf header.
471 See Documentation/kdump.txt for details.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700472
473 enforcing [SELINUX] Set initial enforcing status.
474 Format: {"0" | "1"}
475 See security/selinux/Kconfig help text.
476 0 -- permissive (log only, no denials).
477 1 -- enforcing (deny and log).
478 Default value is 0.
479 Value can be changed at runtime via /selinux/enforce.
480
481 es1370= [HW,OSS]
482 Format: <lineout>[,<micbias>]
483 See also header of sound/oss/es1370.c.
484
485 es1371= [HW,OSS]
486 Format: <spdif>,[<nomix>,[<amplifier>]]
487 See also header of sound/oss/es1371.c.
488
489 ether= [HW,NET] Ethernet cards parameters
490 This option is obsoleted by the "netdev=" option, which
491 has equivalent usage. See its documentation for details.
492
493 eurwdt= [HW,WDT] Eurotech CPU-1220/1410 onboard watchdog.
494 Format: <io>[,<irq>]
495
496 fd_mcs= [HW,SCSI]
497 See header of drivers/scsi/fd_mcs.c.
498
499 fdomain= [HW,SCSI]
500 See header of drivers/scsi/fdomain.c.
501
502 floppy= [HW]
503 See Documentation/floppy.txt.
504
505 ftape= [HW] Floppy Tape subsystem debugging options.
506 See Documentation/ftape.txt.
507
508 gamecon.map[2|3]=
509 [HW,JOY] Multisystem joystick and NES/SNES/PSX pad
510 support via parallel port (up to 5 devices per port)
511 Format: <port#>,<pad1>,<pad2>,<pad3>,<pad4>,<pad5>
512 See also Documentation/input/joystick-parport.txt
513
514 gamma= [HW,DRM]
515
516 gdth= [HW,SCSI]
517 See header of drivers/scsi/gdth.c.
518
519 gpt [EFI] Forces disk with valid GPT signature but
520 invalid Protective MBR to be treated as GPT.
521
522 gscd= [HW,CD]
523 Format: <io>
524
525 gt96100eth= [NET] MIPS GT96100 Advanced Communication Controller
526
527 gus= [HW,OSS]
528 Format: <io>,<irq>,<dma>,<dma16>
529
530 gvp11= [HW,SCSI]
531
532 hashdist= [KNL,NUMA] Large hashes allocated during boot
533 are distributed across NUMA nodes. Defaults on
534 for IA-64, off otherwise.
535
536 hcl= [IA-64] SGI's Hardware Graph compatibility layer
537
538 hd= [EIDE] (E)IDE hard drive subsystem geometry
539 Format: <cyl>,<head>,<sect>
540
541 hd?= [HW] (E)IDE subsystem
542 hd?lun= See Documentation/ide.txt.
543
544 highmem=nn[KMG] [KNL,BOOT] forces the highmem zone to have an exact
545 size of <nn>. This works even on boxes that have no
546 highmem otherwise. This also works to reduce highmem
547 size on bigger boxes.
548
549 hisax= [HW,ISDN]
550 See Documentation/isdn/README.HiSax.
551
552 hugepages= [HW,IA-32,IA-64] Maximal number of HugeTLB pages.
553
554 noirqbalance [IA-32,SMP,KNL] Disable kernel irq balancing
555
556 i8042.direct [HW] Put keyboard port into non-translated mode
557 i8042.dumbkbd [HW] Pretend that controlled can only read data from
558 keyboard and can not control its state
559 (Don't attempt to blink the leds)
560 i8042.noaux [HW] Don't check for auxiliary (== mouse) port
Dmitry Torokhov945ef0d2005-09-04 01:42:00 -0500561 i8042.nokbd [HW] Don't check/create keyboard port
Linus Torvalds1da177e2005-04-16 15:20:36 -0700562 i8042.nomux [HW] Don't check presence of an active multiplexing
563 controller
564 i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX
565 controllers
566 i8042.panicblink=
567 [HW] Frequency with which keyboard LEDs should blink
568 when kernel panics (default is 0.5 sec)
569 i8042.reset [HW] Reset the controller during init and cleanup
570 i8042.unlock [HW] Unlock (ignore) the keylock
571
572 i810= [HW,DRM]
573
Dmitry Torokhove70c9d52005-06-25 14:54:25 -0700574 i8k.ignore_dmi [HW] Continue probing hardware even if DMI data
575 indicates that the driver is running on unsupported
576 hardware.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700577 i8k.force [HW] Activate i8k driver even if SMM BIOS signature
578 does not match list of supported models.
579 i8k.power_status
580 [HW] Report power status in /proc/i8k
581 (disabled by default)
582 i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN
583 capability is set.
584
585 ibmmcascsi= [HW,MCA,SCSI] IBM MicroChannel SCSI adapter
586 See Documentation/mca.txt.
587
588 icn= [HW,ISDN]
589 Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]]
590
591 ide= [HW] (E)IDE subsystem
592 Format: ide=nodma or ide=doubler or ide=reverse
593 See Documentation/ide.txt.
594
595 ide?= [HW] (E)IDE subsystem
596 Format: ide?=noprobe or chipset specific parameters.
597 See Documentation/ide.txt.
598
599 idebus= [HW] (E)IDE subsystem - VLB/PCI bus speed
600 See Documentation/ide.txt.
601
602 idle= [HW]
603 Format: idle=poll or idle=halt
604
605 ihash_entries= [KNL]
606 Set number of hash buckets for inode cache.
607
608 in2000= [HW,SCSI]
609 See header of drivers/scsi/in2000.c.
610
611 init= [KNL]
612 Format: <full_path>
613 Run specified binary instead of /sbin/init as init
614 process.
615
616 initcall_debug [KNL] Trace initcalls as they are executed. Useful
617 for working out where the kernel is dying during
618 startup.
619
620 initrd= [BOOT] Specify the location of the initial ramdisk
621
622 inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver
623 Format: <irq>
624
625 inttest= [IA64]
626
627 io7= [HW] IO7 for Marvel based alpha systems
628 See comment before marvel_specify_io7 in
629 arch/alpha/kernel/core_marvel.c.
630
631 ip= [IP_PNP]
632 See Documentation/nfsroot.txt.
633
634 ip2= [HW] Set IO/IRQ pairs for up to 4 IntelliPort boards
635 See comment before ip2_setup() in drivers/char/ip2.c.
636
637 ips= [HW,SCSI] Adaptec / IBM ServeRAID controller
638 See header of drivers/scsi/ips.c.
639
Alan Cox200803d2005-06-28 20:45:18 -0700640 irqfixup [HW]
641 When an interrupt is not handled search all handlers
642 for it. Intended to get systems with badly broken
643 firmware running.
644
645 irqpoll [HW]
646 When an interrupt is not handled search all handlers
647 for it. Also check all handlers each timer
648 interrupt. Intended to get systems with badly broken
649 firmware running.
650
Linus Torvalds1da177e2005-04-16 15:20:36 -0700651 isapnp= [ISAPNP]
652 Format: <RDP>, <reset>, <pci_scan>, <verbosity>
653
654 isolcpus= [KNL,SMP] Isolate CPUs from the general scheduler.
655 Format: <cpu number>,...,<cpu number>
656 This option can be used to specify one or more CPUs
657 to isolate from the general SMP balancing and scheduling
658 algorithms. The only way to move a process onto or off
659 an "isolated" CPU is via the CPU affinity syscalls.
660 <cpu number> begins at 0 and the maximum value is
661 "number of CPUs in system - 1".
662
663 This option is the preferred way to isolate CPUs. The
664 alternative - manually setting the CPU mask of all tasks
665 in the system can cause problems and suboptimal load
666 balancer performance.
667
668 isp16= [HW,CD]
669 Format: <io>,<irq>,<dma>,<setup>
670
671 iucv= [HW,NET]
672
673 js= [HW,JOY] Analog joystick
674 See Documentation/input/joystick.txt.
675
676 keepinitrd [HW,ARM]
677
678 kstack=N [IA-32, X86-64] Print N words from the kernel stack
679 in oops dumps.
680
681 l2cr= [PPC]
682
683 lapic [IA-32,APIC] Enable the local APIC even if BIOS disabled it.
684
685 lasi= [HW,SCSI] PARISC LASI driver for the 53c700 chip
686 Format: addr:<io>,irq:<irq>
687
688 llsc*= [IA64]
689 See function print_params() in arch/ia64/sn/kernel/llsc4.c.
690
691 load_ramdisk= [RAM] List of ramdisks to load from floppy
692 See Documentation/ramdisk.txt.
693
694 lockd.udpport= [NFS]
695
696 lockd.tcpport= [NFS]
697
698 logibm.irq= [HW,MOUSE] Logitech Bus Mouse Driver
699 Format: <irq>
700
701 loglevel= All Kernel Messages with a loglevel smaller than the
702 console loglevel will be printed to the console. It can
703 also be changed with klogd or other programs. The
704 loglevels are defined as follows:
705
706 0 (KERN_EMERG) system is unusable
707 1 (KERN_ALERT) action must be taken immediately
708 2 (KERN_CRIT) critical conditions
709 3 (KERN_ERR) error conditions
710 4 (KERN_WARNING) warning conditions
711 5 (KERN_NOTICE) normal but significant condition
712 6 (KERN_INFO) informational
713 7 (KERN_DEBUG) debug-level messages
714
715 log_buf_len=n Sets the size of the printk ring buffer, in bytes.
716 Format is n, nk, nM. n must be a power of two. The
717 default is set in kernel config.
718
719 lp=0 [LP] Specify parallel ports to use, e.g,
720 lp=port[,port...] lp=none,parport0 (lp0 not configured, lp1 uses
721 lp=reset first parallel port). 'lp=0' disables the
722 lp=auto printer driver. 'lp=reset' (which can be
723 specified in addition to the ports) causes
724 attached printers to be reset. Using
725 lp=port1,port2,... specifies the parallel ports
726 to associate lp devices with, starting with
727 lp0. A port specification may be 'none' to skip
728 that lp device, or a parport name such as
729 'parport0'. Specifying 'lp=auto' instead of a
730 port specification list means that device IDs
731 from each port should be examined, to see if
732 an IEEE 1284-compliant printer is attached; if
733 so, the driver will manage that printer.
734 See also header of drivers/char/lp.c.
735
736 lpj=n [KNL]
737 Sets loops_per_jiffy to given constant, thus avoiding
738 time-consuming boot-time autodetection (up to 250 ms per
739 CPU). 0 enables autodetection (default). To determine
740 the correct value for your kernel, boot with normal
741 autodetection and see what value is printed. Note that
742 on SMP systems the preset will be applied to all CPUs,
743 which is likely to cause problems if your CPUs need
744 significantly divergent settings. An incorrect value
745 will cause delays in the kernel to be wrong, leading to
746 unpredictable I/O errors and other breakage. Although
747 unlikely, in the extreme case this might damage your
748 hardware.
749
750 ltpc= [NET]
751 Format: <io>,<irq>,<dma>
752
753 mac5380= [HW,SCSI]
754 Format: <can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
755
756 mac53c9x= [HW,SCSI]
757 Format: <num_esps>,<disconnect>,<nosync>,<can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
758
759 machvec= [IA64]
760 Force the use of a particular machine-vector (machvec) in a generic
761 kernel. Example: machvec=hpzx1_swiotlb
762
763 mad16= [HW,OSS]
764 Format: <io>,<irq>,<dma>,<dma16>,<mpu_io>,<mpu_irq>,<joystick>
765
766 maui= [HW,OSS]
767 Format: <io>,<irq>
768
769 max_loop= [LOOP] Maximum number of loopback devices that can
770 be mounted
771 Format: <1-256>
772
773 maxcpus= [SMP] Maximum number of processors that an SMP kernel
774 should make use of
775
Bob Picco2b2c3752005-06-29 18:00:00 -0700776 max_addr=[KMG] [KNL,BOOT,ia64] All physical memory greater than or
777 equal to this physical address is ignored.
778
Linus Torvalds1da177e2005-04-16 15:20:36 -0700779 max_luns= [SCSI] Maximum number of LUNs to probe
780 Should be between 1 and 2^32-1.
781
782 max_report_luns=
783 [SCSI] Maximum number of LUNs received
784 Should be between 1 and 16384.
785
786 mca-pentium [BUGS=IA-32]
787
788 mcatest= [IA-64]
789
790 mcd= [HW,CD]
791 Format: <port>,<irq>,<mitsumi_bug_93_wait>
792
793 mcdx= [HW,CD]
794
795 mce [IA-32] Machine Check Exception
796
797 md= [HW] RAID subsystems devices and level
798 See Documentation/md.txt.
799
800 mdacon= [MDA]
801 Format: <first>,<last>
802 Specifies range of consoles to be captured by the MDA.
803
804 mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory
805 Amount of memory to be used when the kernel is not able
806 to see the whole system memory or for test.
807 [IA-32] Use together with memmap= to avoid physical
808 address space collisions. Without memmap= PCI devices
809 could be placed at addresses belonging to unused RAM.
810
811 mem=nopentium [BUGS=IA-32] Disable usage of 4MB pages for kernel
812 memory.
813
814 memmap=exactmap [KNL,IA-32] Enable setting of an exact
815 E820 memory map, as specified by the user.
816 Such memmap=exactmap lines can be constructed based on
817 BIOS output or other requirements. See the memmap=nn@ss
818 option description.
819
820 memmap=nn[KMG]@ss[KMG]
821 [KNL] Force usage of a specific region of memory
822 Region of memory to be used, from ss to ss+nn.
823
824 memmap=nn[KMG]#ss[KMG]
825 [KNL,ACPI] Mark specific memory as ACPI data.
826 Region of memory to be used, from ss to ss+nn.
827
828 memmap=nn[KMG]$ss[KMG]
829 [KNL,ACPI] Mark specific memory as reserved.
830 Region of memory to be used, from ss to ss+nn.
831
832 meye.*= [HW] Set MotionEye Camera parameters
833 See Documentation/video4linux/meye.txt.
834
835 mga= [HW,DRM]
836
837 mousedev.tap_time=
838 [MOUSE] Maximum time between finger touching and
839 leaving touchpad surface for touch to be considered
840 a tap and be reported as a left button click (for
841 touchpads working in absolute mode only).
842 Format: <msecs>
843 mousedev.xres= [MOUSE] Horizontal screen resolution, used for devices
844 reporting absolute coordinates, such as tablets
845 mousedev.yres= [MOUSE] Vertical screen resolution, used for devices
846 reporting absolute coordinates, such as tablets
847
848 mpu401= [HW,OSS]
849 Format: <io>,<irq>
850
851 MTD_Partition= [MTD]
852 Format: <name>,<region-number>,<size>,<offset>
853
854 MTD_Region= [MTD]
855 Format: <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
856
857 mtdparts= [MTD]
858 See drivers/mtd/cmdline.c.
859
860 mtouchusb.raw_coordinates=
861 [HW] Make the MicroTouch USB driver use raw coordinates ('y', default)
862 or cooked coordinates ('n')
863
864 n2= [NET] SDL Inc. RISCom/N2 synchronous serial card
865
866 NCR_D700= [HW,SCSI]
867 See header of drivers/scsi/NCR_D700.c.
868
869 ncr5380= [HW,SCSI]
870
871 ncr53c400= [HW,SCSI]
872
873 ncr53c400a= [HW,SCSI]
874
875 ncr53c406a= [HW,SCSI]
876
877 ncr53c8xx= [HW,SCSI]
878
879 netdev= [NET] Network devices parameters
880 Format: <irq>,<io>,<mem_start>,<mem_end>,<name>
881 Note that mem_start is often overloaded to mean
882 something different and driver-specific.
883
884 nfsaddrs= [NFS]
885 See Documentation/nfsroot.txt.
886
887 nfsroot= [NFS] nfs root filesystem for disk-less boxes.
888 See Documentation/nfsroot.txt.
889
890 nmi_watchdog= [KNL,BUGS=IA-32] Debugging features for SMP kernels
891
892 no387 [BUGS=IA-32] Tells the kernel to use the 387 maths
893 emulation library even if a 387 maths coprocessor
894 is present.
895
896 noalign [KNL,ARM]
897
898 noapic [SMP,APIC] Tells the kernel to not make use of any
899 IOAPICs that may be present in the system.
900
901 noasync [HW,M68K] Disables async and sync negotiation for
902 all devices.
903
904 nobats [PPC] Do not use BATs for mapping kernel lowmem
905 on "Classic" PPC cores.
906
907 nocache [ARM]
908
909 nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects.
910
911 noexec [IA-64]
912
913 noexec [IA-32, X86-64]
914 noexec=on: enable non-executable mappings (default)
915 noexec=off: disable nn-executable mappings
916
917 nofxsr [BUGS=IA-32]
918
919 nohlt [BUGS=ARM]
920
921 no-hlt [BUGS=IA-32] Tells the kernel that the hlt
922 instruction doesn't work correctly and not to
923 use it.
924
925 nohalt [IA-64] Tells the kernel not to use the power saving
926 function PAL_HALT_LIGHT when idle. This increases
927 power-consumption. On the positive side, it reduces
928 interrupt wake-up latency, which may improve performance
929 in certain environments such as networked servers or
930 real-time systems.
931
932 noirqdebug [IA-32] Disables the code which attempts to detect and
933 disable unhandled interrupt sources.
934
935 noisapnp [ISAPNP] Disables ISA PnP code.
936
937 noinitrd [RAM] Tells the kernel not to load any configured
938 initial RAM disk.
939
940 nointroute [IA-64]
941
942 nolapic [IA-32,APIC] Do not enable or use the local APIC.
943
944 noltlbs [PPC] Do not use large page/tlb entries for kernel
945 lowmem mapping on PPC40x.
946
947 nomce [IA-32] Machine Check Exception
948
949 noresidual [PPC] Don't use residual data on PReP machines.
950
951 noresume [SWSUSP] Disables resume and restore original swap space.
952
953 no-scroll [VGA] Disables scrollback.
954 This is required for the Braillex ib80-piezo Braille
955 reader made by F.H. Papenmeier (Germany).
956
957 nosbagart [IA-64]
958
959 nosmp [SMP] Tells an SMP kernel to act as a UP kernel.
960
961 nosync [HW,M68K] Disables sync negotiation for all devices.
962
963 notsc [BUGS=IA-32] Disable Time Stamp Counter
964
965 nousb [USB] Disable the USB subsystem
966
967 nowb [ARM]
968
969 opl3= [HW,OSS]
970 Format: <io>
971
972 opl3sa= [HW,OSS]
973 Format: <io>,<irq>,<dma>,<dma2>,<mpu_io>,<mpu_irq>
974
975 opl3sa2= [HW,OSS]
976 Format: <io>,<irq>,<dma>,<dma2>,<mss_io>,<mpu_io>,<ymode>,<loopback>[,<isapnp>,<multiple]
977
978 oprofile.timer= [HW]
979 Use timer interrupt instead of performance counters
980
981 optcd= [HW,CD]
982 Format: <io>
983
984 osst= [HW,SCSI] SCSI Tape Driver
985 Format: <buffer_size>,<write_threshold>
986 See also Documentation/scsi/st.txt.
987
988 panic= [KNL] Kernel behaviour on panic
989 Format: <timeout>
990
991 parkbd.port= [HW] Parallel port number the keyboard adapter is
992 connected to, default is 0.
993 Format: <parport#>
994 parkbd.mode= [HW] Parallel port keyboard adapter mode of operation,
995 0 for XT, 1 for AT (default is AT).
996 Format: <mode>
997
998 parport=0 [HW,PPT] Specify parallel ports. 0 disables.
999 parport=auto Use 'auto' to force the driver to use
1000 parport=0xBBB[,IRQ[,DMA]] any IRQ/DMA settings detected (the
1001 default is to ignore detected IRQ/DMA
1002 settings because of possible
1003 conflicts). You can specify the base
1004 address, IRQ, and DMA settings; IRQ and
1005 DMA should be numbers, or 'auto' (for
1006 using detected settings on that
1007 particular port), or 'nofifo' (to avoid
1008 using a FIFO even if it is detected).
1009 Parallel ports are assigned in the
1010 order they are specified on the command
1011 line, starting with parport0.
1012
1013 parport_init_mode=
1014 [HW,PPT] Configure VIA parallel port to
1015 operate in specific mode. This is
1016 necessary on Pegasos computer where
1017 firmware has no options for setting up
1018 parallel port mode and sets it to
1019 spp. Currently this function knows
1020 686a and 8231 chips.
1021 Format: [spp|ps2|epp|ecp|ecpepp]
1022
1023 pas2= [HW,OSS]
1024 Format: <io>,<irq>,<dma>,<dma16>,<sb_io>,<sb_irq>,<sb_dma>,<sb_dma16>
1025
1026 pas16= [HW,SCSI]
1027 See header of drivers/scsi/pas16.c.
1028
1029 pcbit= [HW,ISDN]
1030
1031 pcd. [PARIDE]
1032 See header of drivers/block/paride/pcd.c.
1033 See also Documentation/paride.txt.
1034
1035 pci=option[,option...] [PCI] various PCI subsystem options:
1036 off [IA-32] don't probe for the PCI bus
1037 bios [IA-32] force use of PCI BIOS, don't access
1038 the hardware directly. Use this if your machine
1039 has a non-standard PCI host bridge.
1040 nobios [IA-32] disallow use of PCI BIOS, only direct
1041 hardware access methods are allowed. Use this
1042 if you experience crashes upon bootup and you
1043 suspect they are caused by the BIOS.
1044 conf1 [IA-32] Force use of PCI Configuration Mechanism 1.
1045 conf2 [IA-32] Force use of PCI Configuration Mechanism 2.
1046 nosort [IA-32] Don't sort PCI devices according to
1047 order given by the PCI BIOS. This sorting is done
1048 to get a device order compatible with older kernels.
1049 biosirq [IA-32] Use PCI BIOS calls to get the interrupt
1050 routing table. These calls are known to be buggy
1051 on several machines and they hang the machine when used,
1052 but on other computers it's the only way to get the
1053 interrupt routing table. Try this option if the kernel
1054 is unable to allocate IRQs or discover secondary PCI
1055 buses on your motherboard.
1056 rom [IA-32] Assign address space to expansion ROMs.
1057 Use with caution as certain devices share address
1058 decoders between ROMs and other resources.
1059 irqmask=0xMMMM [IA-32] Set a bit mask of IRQs allowed to be assigned
1060 automatically to PCI devices. You can make the kernel
1061 exclude IRQs of your ISA cards this way.
jayalk@intworks.biz120bb422005-03-21 20:20:42 -08001062 pirqaddr=0xAAAAA [IA-32] Specify the physical address
1063 of the PIRQ table (normally generated
1064 by the BIOS) if it is outside the
1065 F0000h-100000h range.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001066 lastbus=N [IA-32] Scan all buses till bus #N. Can be useful
1067 if the kernel is unable to find your secondary buses
1068 and you want to tell it explicitly which ones they are.
1069 assign-busses [IA-32] Always assign all PCI bus
1070 numbers ourselves, overriding
1071 whatever the firmware may have
1072 done.
1073 usepirqmask [IA-32] Honor the possible IRQ mask
1074 stored in the BIOS $PIR table. This is
1075 needed on some systems with broken
1076 BIOSes, notably some HP Pavilion N5400
1077 and Omnibook XE3 notebooks. This will
1078 have no effect if ACPI IRQ routing is
1079 enabled.
1080 noacpi [IA-32] Do not use ACPI for IRQ routing
1081 or for PCI scanning.
1082 routeirq Do IRQ routing for all PCI devices.
1083 This is normally done in pci_enable_device(),
1084 so this option is a temporary workaround
1085 for broken drivers that don't call it.
1086
1087 firmware [ARM] Do not re-enumerate the bus but
1088 instead just use the configuration
1089 from the bootloader. This is currently
1090 used on IXP2000 systems where the
1091 bus has to be configured a certain way
1092 for adjunct CPUs.
1093
1094 pcmv= [HW,PCMCIA] BadgePAD 4
1095
1096 pd. [PARIDE]
1097 See Documentation/paride.txt.
1098
1099 pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at
1100 boot time.
1101 Format: { 0 | 1 }
1102 See arch/parisc/kernel/pdc_chassis.c
1103
1104 pf. [PARIDE]
1105 See Documentation/paride.txt.
1106
1107 pg. [PARIDE]
1108 See Documentation/paride.txt.
1109
1110 pirq= [SMP,APIC] Manual mp-table setup
1111 See Documentation/i386/IO-APIC.txt.
1112
1113 plip= [PPT,NET] Parallel port network link
1114 Format: { parport<nr> | timid | 0 }
1115 See also Documentation/parport.txt.
1116
1117 pnpacpi= [ACPI]
1118 { off }
1119
1120 pnpbios= [ISAPNP]
1121 { on | off | curr | res | no-curr | no-res }
1122
1123 pnp_reserve_irq=
1124 [ISAPNP] Exclude IRQs for the autoconfiguration
1125
1126 pnp_reserve_dma=
1127 [ISAPNP] Exclude DMAs for the autoconfiguration
1128
1129 pnp_reserve_io= [ISAPNP] Exclude I/O ports for the autoconfiguration
1130 Ranges are in pairs (I/O port base and size).
1131
1132 pnp_reserve_mem=
1133 [ISAPNP] Exclude memory regions for the autoconfiguration
1134 Ranges are in pairs (memory base and size).
1135
1136 profile= [KNL] Enable kernel profiling via /proc/profile
1137 { schedule | <number> }
1138 (param: schedule - profile schedule points}
1139 (param: profile step/bucket size as a power of 2 for
1140 statistical time based profiling)
1141
1142 processor.max_cstate= [HW, ACPI]
1143 Limit processor to maximum C-state
1144 max_cstate=9 overrides any DMI blacklist limit.
1145
1146 prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk
1147 before loading.
1148 See Documentation/ramdisk.txt.
1149
1150 psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to
Kenan Esau02d7f582005-05-29 02:30:22 -05001151 probe for (bare|imps|exps|lifebook|any).
Linus Torvalds1da177e2005-04-16 15:20:36 -07001152 psmouse.rate= [HW,MOUSE] Set desired mouse report rate, in reports
1153 per second.
1154 psmouse.resetafter=
1155 [HW,MOUSE] Try to reset the device after so many bad packets
1156 (0 = never).
1157 psmouse.resolution=
1158 [HW,MOUSE] Set desired mouse resolution, in dpi.
1159 psmouse.smartscroll=
1160 [HW,MOUSE] Controls Logitech smartscroll autorepeat,
1161 0 = disabled, 1 = enabled (default).
1162
1163 pss= [HW,OSS] Personal Sound System (ECHO ESC614)
1164 Format: <io>,<mss_io>,<mss_irq>,<mss_dma>,<mpu_io>,<mpu_irq>
1165
1166 pt. [PARIDE]
1167 See Documentation/paride.txt.
1168
1169 quiet= [KNL] Disable log messages
1170
1171 r128= [HW,DRM]
1172
1173 raid= [HW,RAID]
1174 See Documentation/md.txt.
1175
1176 ramdisk= [RAM] Sizes of RAM disks in kilobytes [deprecated]
1177 See Documentation/ramdisk.txt.
1178
1179 ramdisk_blocksize=
1180 [RAM]
1181 See Documentation/ramdisk.txt.
1182
1183 ramdisk_size= [RAM] Sizes of RAM disks in kilobytes
1184 New name for the ramdisk parameter.
1185 See Documentation/ramdisk.txt.
1186
Olof Johanssonffdfc402005-09-06 15:17:19 -07001187 rdinit= [KNL]
1188 Format: <full_path>
1189 Run specified binary instead of /init from the ramdisk,
1190 used for early userspace startup. See initrd.
1191
Linus Torvalds1da177e2005-04-16 15:20:36 -07001192 reboot= [BUGS=IA-32,BUGS=ARM,BUGS=IA-64] Rebooting mode
1193 Format: <reboot_mode>[,<reboot_mode2>[,...]]
1194 See arch/*/kernel/reboot.c.
1195
1196 reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
1197
1198 resume= [SWSUSP] Specify the partition device for software suspension
1199
1200 rhash_entries= [KNL,NET]
1201 Set number of hash buckets for route cache
1202
1203 riscom8= [HW,SERIAL]
1204 Format: <io_board1>[,<io_board2>[,...<io_boardN>]]
1205
1206 ro [KNL] Mount root device read-only on boot
1207
1208 root= [KNL] Root filesystem
1209
1210 rootdelay= [KNL] Delay (in seconds) to pause before attempting to
1211 mount the root filesystem
1212
1213 rootflags= [KNL] Set root filesystem mount option string
1214
1215 rootfstype= [KNL] Set root filesystem type
1216
1217 rw [KNL] Mount root device read-write on boot
1218
1219 S [KNL] Run init in single mode
1220
1221 sa1100ir [NET]
1222 See drivers/net/irda/sa1100_ir.c.
1223
1224 sb= [HW,OSS]
1225 Format: <io>,<irq>,<dma>,<dma2>
1226
1227 sbni= [NET] Granch SBNI12 leased line adapter
1228
1229 sbpcd= [HW,CD] Soundblaster CD adapter
1230 Format: <io>,<type>
1231 See a comment before function sbpcd_setup() in
1232 drivers/cdrom/sbpcd.c.
1233
1234 sc1200wdt= [HW,WDT] SC1200 WDT (watchdog) driver
1235 Format: <io>[,<timeout>[,<isapnp>]]
1236
1237 scsi_debug_*= [SCSI]
1238 See drivers/scsi/scsi_debug.c.
1239
1240 scsi_default_dev_flags=
1241 [SCSI] SCSI default device flags
1242 Format: <integer>
1243
1244 scsi_dev_flags= [SCSI] Black/white list entry for vendor and model
1245 Format: <vendor>:<model>:<flags>
1246 (flags are integer value)
1247
1248 scsi_logging= [SCSI]
1249
1250 selinux [SELINUX] Disable or enable SELinux at boot time.
1251 Format: { "0" | "1" }
1252 See security/selinux/Kconfig help text.
1253 0 -- disable.
1254 1 -- enable.
1255 Default value is set via kernel config option.
1256 If enabled at boot time, /selinux/disable can be used
1257 later to disable prior to initial policy load.
1258
1259 serialnumber [BUGS=IA-32]
1260
1261 sg_def_reserved_size=
1262 [SCSI]
1263
1264 sgalaxy= [HW,OSS]
1265 Format: <io>,<irq>,<dma>,<dma2>,<sgbase>
1266
1267 shapers= [NET]
1268 Maximal number of shapers.
1269
1270 sim710= [SCSI,HW]
1271 See header of drivers/scsi/sim710.c.
1272
1273 simeth= [IA-64]
1274 simscsi=
1275
1276 sjcd= [HW,CD]
1277 Format: <io>,<irq>,<dma>
1278 See header of drivers/cdrom/sjcd.c.
1279
1280 slram= [HW,MTD]
1281
1282 smart2= [HW]
1283 Format: <io1>[,<io2>[,...,<io8>]]
1284
1285 snd-ad1816a= [HW,ALSA]
1286
1287 snd-ad1848= [HW,ALSA]
1288
1289 snd-ali5451= [HW,ALSA]
1290
1291 snd-als100= [HW,ALSA]
1292
1293 snd-als4000= [HW,ALSA]
1294
1295 snd-azt2320= [HW,ALSA]
1296
1297 snd-cmi8330= [HW,ALSA]
1298
1299 snd-cmipci= [HW,ALSA]
1300
1301 snd-cs4231= [HW,ALSA]
1302
1303 snd-cs4232= [HW,ALSA]
1304
1305 snd-cs4236= [HW,ALSA]
1306
1307 snd-cs4281= [HW,ALSA]
1308
1309 snd-cs46xx= [HW,ALSA]
1310
1311 snd-dt019x= [HW,ALSA]
1312
1313 snd-dummy= [HW,ALSA]
1314
1315 snd-emu10k1= [HW,ALSA]
1316
1317 snd-ens1370= [HW,ALSA]
1318
1319 snd-ens1371= [HW,ALSA]
1320
1321 snd-es968= [HW,ALSA]
1322
1323 snd-es1688= [HW,ALSA]
1324
1325 snd-es18xx= [HW,ALSA]
1326
1327 snd-es1938= [HW,ALSA]
1328
1329 snd-es1968= [HW,ALSA]
1330
1331 snd-fm801= [HW,ALSA]
1332
1333 snd-gusclassic= [HW,ALSA]
1334
1335 snd-gusextreme= [HW,ALSA]
1336
1337 snd-gusmax= [HW,ALSA]
1338
1339 snd-hdsp= [HW,ALSA]
1340
1341 snd-ice1712= [HW,ALSA]
1342
1343 snd-intel8x0= [HW,ALSA]
1344
1345 snd-interwave= [HW,ALSA]
1346
1347 snd-interwave-stb=
1348 [HW,ALSA]
1349
1350 snd-korg1212= [HW,ALSA]
1351
1352 snd-maestro3= [HW,ALSA]
1353
1354 snd-mpu401= [HW,ALSA]
1355
1356 snd-mtpav= [HW,ALSA]
1357
1358 snd-nm256= [HW,ALSA]
1359
1360 snd-opl3sa2= [HW,ALSA]
1361
1362 snd-opti92x-ad1848=
1363 [HW,ALSA]
1364
1365 snd-opti92x-cs4231=
1366 [HW,ALSA]
1367
1368 snd-opti93x= [HW,ALSA]
1369
1370 snd-pmac= [HW,ALSA]
1371
1372 snd-rme32= [HW,ALSA]
1373
1374 snd-rme96= [HW,ALSA]
1375
1376 snd-rme9652= [HW,ALSA]
1377
1378 snd-sb8= [HW,ALSA]
1379
1380 snd-sb16= [HW,ALSA]
1381
1382 snd-sbawe= [HW,ALSA]
1383
1384 snd-serial= [HW,ALSA]
1385
1386 snd-sgalaxy= [HW,ALSA]
1387
1388 snd-sonicvibes= [HW,ALSA]
1389
1390 snd-sun-amd7930=
1391 [HW,ALSA]
1392
1393 snd-sun-cs4231= [HW,ALSA]
1394
1395 snd-trident= [HW,ALSA]
1396
1397 snd-usb-audio= [HW,ALSA,USB]
1398
1399 snd-via82xx= [HW,ALSA]
1400
1401 snd-virmidi= [HW,ALSA]
1402
1403 snd-wavefront= [HW,ALSA]
1404
1405 snd-ymfpci= [HW,ALSA]
1406
1407 sonicvibes= [HW,OSS]
1408 Format: <reverb>
1409
1410 sonycd535= [HW,CD]
1411 Format: <io>[,<irq>]
1412
1413 sonypi.*= [HW] Sony Programmable I/O Control Device driver
1414 See Documentation/sonypi.txt
1415
1416 specialix= [HW,SERIAL] Specialix multi-serial port adapter
1417 See Documentation/specialix.txt.
1418
1419 spia_io_base= [HW,MTD]
1420 spia_fio_base=
1421 spia_pedr=
1422 spia_peddr=
1423
1424 sscape= [HW,OSS]
1425 Format: <io>,<irq>,<dma>,<mpu_io>,<mpu_irq>
1426
1427 st= [HW,SCSI] SCSI tape parameters (buffers, etc.)
1428 See Documentation/scsi/st.txt.
1429
1430 st0x= [HW,SCSI]
1431 See header of drivers/scsi/seagate.c.
1432
1433 sti= [PARISC,HW]
1434 Format: <num>
1435 Set the STI (builtin display/keyboard on the HP-PARISC
1436 machines) console (graphic card) which should be used
1437 as the initial boot-console.
1438 See also comment in drivers/video/console/sticore.c.
1439
1440 sti_font= [HW]
1441 See comment in drivers/video/console/sticore.c.
1442
1443 stifb= [HW]
1444 Format: bpp:<bpp1>[:<bpp2>[:<bpp3>...]]
1445
1446 stram_swap= [HW,M68k]
1447
1448 swiotlb= [IA-64] Number of I/O TLB slabs
1449
1450 switches= [HW,M68k]
1451
1452 sym53c416= [HW,SCSI]
1453 See header of drivers/scsi/sym53c416.c.
1454
1455 t128= [HW,SCSI]
1456 See header of drivers/scsi/t128.c.
1457
1458 tdfx= [HW,DRM]
1459
1460 thash_entries= [KNL,NET]
1461 Set number of hash buckets for TCP connection
1462
1463 time Show timing data prefixed to each printk message line
1464
1465 tipar.timeout= [HW,PPT]
1466 Set communications timeout in tenths of a second
1467 (default 15).
1468
1469 tipar.delay= [HW,PPT]
1470 Set inter-bit delay in microseconds (default 10).
1471
1472 tmc8xx= [HW,SCSI]
1473 See header of drivers/scsi/seagate.c.
1474
1475 tmscsim= [HW,SCSI]
1476 See comment before function dc390_setup() in
1477 drivers/scsi/tmscsim.c.
1478
1479 tp720= [HW,PS2]
1480
1481 trix= [HW,OSS] MediaTrix AudioTrix Pro
1482 Format: <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq>
1483
1484 tsdev.xres= [TS] Horizontal screen resolution.
1485 tsdev.yres= [TS] Vertical screen resolution.
1486
1487 turbografx.map[2|3]=
1488 [HW,JOY] TurboGraFX parallel port interface
1489 Format: <port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7>
1490 See also Documentation/input/joystick-parport.txt
1491
1492 u14-34f= [HW,SCSI] UltraStor 14F/34F SCSI host adapter
1493 See header of drivers/scsi/u14-34f.c.
1494
1495 uart401= [HW,OSS]
1496 Format: <io>,<irq>
1497
1498 uart6850= [HW,OSS]
1499 Format: <io>,<irq>
1500
1501 usb-handoff [HW] Enable early USB BIOS -> OS handoff
1502
1503 usbhid.mousepoll=
1504 [USBHID] The interval which mice are to be polled at.
1505
1506 video= [FB] Frame buffer configuration
1507 See Documentation/fb/modedb.txt.
1508
1509 vga= [BOOT,IA-32] Select a particular video mode
1510 See Documentation/i386/boot.txt and Documentation/svga.txt.
1511 Use vga=ask for menu.
1512 This is actually a boot loader parameter; the value is
1513 passed to the kernel using a special protocol.
1514
1515 vmalloc=nn[KMG] [KNL,BOOT] forces the vmalloc area to have an exact
1516 size of <nn>. This can be used to increase the
1517 minimum size (128MB on x86). It can also be used to
1518 decrease the size and leave more room for directly
1519 mapped kernel RAM.
1520
1521 vmhalt= [KNL,S390]
1522
1523 vmpoff= [KNL,S390]
1524
1525 waveartist= [HW,OSS]
1526 Format: <io>,<irq>,<dma>,<dma2>
1527
1528 wd33c93= [HW,SCSI]
1529 See header of drivers/scsi/wd33c93.c.
1530
1531 wd7000= [HW,SCSI]
1532 See header of drivers/scsi/wd7000.c.
1533
1534 wdt= [WDT] Watchdog
1535 See Documentation/watchdog/watchdog.txt.
1536
1537 xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks.
1538 xd_geo= See header of drivers/block/xd.c.
1539
1540 xirc2ps_cs= [NET,PCMCIA]
1541 Format: <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
1542
1543
1544
1545Changelog:
1546
1547 The last known update (for 2.4.0) - the changelog was not kept before.
1548 2000-06-?? Mr. Unknown
1549
1550 Update for 2.5.49, description for most of the options introduced,
1551 references to other documentation (C files, READMEs, ..), added S390,
1552 PPC, SPARC, MTD, ALSA and OSS category. Minor corrections and
1553 reformatting.
1554 2002-11-24 Petr Baudis <pasky@ucw.cz>
1555 Randy Dunlap <randy.dunlap@verizon.net>
1556
1557TODO:
1558
1559 Add documentation for ALSA options.
1560 Add more DRM drivers.