kernel-parameters.txt 43 KB

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  1. February 2003 Kernel Parameters v2.5.59
  2. ~~~~~~~~~~~~~~~~~
  3. The following is a consolidated list of the kernel parameters as implemented
  4. (mostly) by the __setup() macro and sorted into English Dictionary order
  5. (defined as ignoring all punctuation and sorting digits before letters in a
  6. case insensitive manner), and with descriptions where known.
  7. Module parameters for loadable modules are specified only as the
  8. parameter name with optional '=' and value as appropriate, such as:
  9. modprobe usbcore blinkenlights=1
  10. Module parameters for modules that are built into the kernel image
  11. are specified on the kernel command line with the module name plus
  12. '.' plus parameter name, with '=' and value if appropriate, such as:
  13. usbcore.blinkenlights=1
  14. The text in square brackets at the beginning of the description state the
  15. restrictions on the kernel for the said kernel parameter to be valid. The
  16. restrictions referred to are that the relevant option is valid if:
  17. ACPI ACPI support is enabled.
  18. ALSA ALSA sound support is enabled.
  19. APIC APIC support is enabled.
  20. APM Advanced Power Management support is enabled.
  21. AX25 Appropriate AX.25 support is enabled.
  22. CD Appropriate CD support is enabled.
  23. DEVFS devfs support is enabled.
  24. DRM Direct Rendering Management support is enabled.
  25. EDD BIOS Enhanced Disk Drive Services (EDD) is enabled
  26. EFI EFI Partitioning (GPT) is enabled
  27. EIDE EIDE/ATAPI support is enabled.
  28. FB The frame buffer device is enabled.
  29. HW Appropriate hardware is enabled.
  30. IA-32 IA-32 aka i386 architecture is enabled.
  31. IA-64 IA-64 architecture is enabled.
  32. IOSCHED More than one I/O scheduler is enabled.
  33. IP_PNP IP DCHP, BOOTP, or RARP is enabled.
  34. ISAPNP ISA PnP code is enabled.
  35. ISDN Appropriate ISDN support is enabled.
  36. JOY Appropriate joystick support is enabled.
  37. LP Printer support is enabled.
  38. LOOP Loopback device support is enabled.
  39. M68k M68k architecture is enabled.
  40. These options have more detailed description inside of
  41. Documentation/m68k/kernel-options.txt.
  42. MCA MCA bus support is enabled.
  43. MDA MDA console support is enabled.
  44. MOUSE Appropriate mouse support is enabled.
  45. MTD MTD support is enabled.
  46. NET Appropriate network support is enabled.
  47. NUMA NUMA support is enabled.
  48. NFS Appropriate NFS support is enabled.
  49. OSS OSS sound support is enabled.
  50. PARIDE The ParIDE subsystem is enabled.
  51. PARISC The PA-RISC architecture is enabled.
  52. PCI PCI bus support is enabled.
  53. PCMCIA The PCMCIA subsystem is enabled.
  54. PNP Plug & Play support is enabled.
  55. PPC PowerPC architecture is enabled.
  56. PPT Parallel port support is enabled.
  57. PS2 Appropriate PS/2 support is enabled.
  58. RAM RAM disk support is enabled.
  59. S390 S390 architecture is enabled.
  60. SCSI Appropriate SCSI support is enabled.
  61. A lot of drivers has their options described inside of
  62. Documentation/scsi/.
  63. SELINUX SELinux support is enabled.
  64. SERIAL Serial support is enabled.
  65. SMP The kernel is an SMP kernel.
  66. SPARC Sparc architecture is enabled.
  67. SWSUSP Software suspension is enabled.
  68. TS Appropriate touchscreen support is enabled.
  69. USB USB support is enabled.
  70. USBHID USB Human Interface Device support is enabled.
  71. V4L Video For Linux support is enabled.
  72. VGA The VGA console has been enabled.
  73. VT Virtual terminal support is enabled.
  74. WDT Watchdog support is enabled.
  75. XT IBM PC/XT MFM hard disk support is enabled.
  76. X86-64 X86-64 architecture is enabled.
  77. More X86-64 boot options can be found in
  78. Documentation/x86_64/boot-options.txt .
  79. In addition, the following text indicates that the option:
  80. BUGS= Relates to possible processor bugs on the said processor.
  81. KNL Is a kernel start-up parameter.
  82. BOOT Is a boot loader parameter.
  83. Parameters denoted with BOOT are actually interpreted by the boot
  84. loader, and have no meaning to the kernel directly.
  85. Do not modify the syntax of boot loader parameters without extreme
  86. need or coordination with <Documentation/i386/boot.txt>.
  87. Note that ALL kernel parameters listed below are CASE SENSITIVE, and that
  88. a trailing = on the name of any parameter states that that parameter will
  89. be entered as an environment variable, whereas its absence indicates that
  90. it will appear as a kernel argument readable via /proc/cmdline by programs
  91. running once the system is up.
  92. 53c7xx= [HW,SCSI] Amiga SCSI controllers
  93. See header of drivers/scsi/53c7xx.c.
  94. See also Documentation/scsi/ncr53c7xx.txt.
  95. acpi= [HW,ACPI] Advanced Configuration and Power Interface
  96. Format: { force | off | ht | strict }
  97. force -- enable ACPI if default was off
  98. off -- disable ACPI if default was on
  99. noirq -- do not use ACPI for IRQ routing
  100. ht -- run only enough ACPI to enable Hyper Threading
  101. strict -- Be less tolerant of platforms that are not
  102. strictly ACPI specification compliant.
  103. See also Documentation/pm.txt, pci=noacpi
  104. acpi_sleep= [HW,ACPI] Sleep options
  105. Format: { s3_bios, s3_mode }
  106. See Documentation/power/video.txt
  107. acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
  108. Format: { level | edge | high | low }
  109. acpi_irq_balance [HW,ACPI] ACPI will balance active IRQs
  110. default in APIC mode
  111. acpi_irq_nobalance [HW,ACPI] ACPI will not move active IRQs (default)
  112. default in PIC mode
  113. acpi_irq_pci= [HW,ACPI] If irq_balance, Clear listed IRQs for use by PCI
  114. Format: <irq>,<irq>...
  115. acpi_irq_isa= [HW,ACPI] If irq_balance, Mark listed IRQs used by ISA
  116. Format: <irq>,<irq>...
  117. acpi_osi= [HW,ACPI] empty param disables _OSI
  118. acpi_serialize [HW,ACPI] force serialization of AML methods
  119. acpi_skip_timer_override [HW,ACPI]
  120. Recognize and ignore IRQ0/pin2 Interrupt Override.
  121. For broken nForce2 BIOS resulting in XT-PIC timer.
  122. acpi_dbg_layer= [HW,ACPI]
  123. Format: <int>
  124. Each bit of the <int> indicates an acpi debug layer,
  125. 1: enable, 0: disable. It is useful for boot time
  126. debugging. After system has booted up, it can be set
  127. via /proc/acpi/debug_layer.
  128. acpi_dbg_level= [HW,ACPI]
  129. Format: <int>
  130. Each bit of the <int> indicates an acpi debug level,
  131. 1: enable, 0: disable. It is useful for boot time
  132. debugging. After system has booted up, it can be set
  133. via /proc/acpi/debug_level.
  134. acpi_fake_ecdt [HW,ACPI] Workaround failure due to BIOS lacking ECDT
  135. ad1816= [HW,OSS]
  136. Format: <io>,<irq>,<dma>,<dma2>
  137. See also Documentation/sound/oss/AD1816.
  138. ad1848= [HW,OSS]
  139. Format: <io>,<irq>,<dma>,<dma2>,<type>
  140. adlib= [HW,OSS]
  141. Format: <io>
  142. advansys= [HW,SCSI]
  143. See header of drivers/scsi/advansys.c.
  144. advwdt= [HW,WDT] Advantech WDT
  145. Format: <iostart>,<iostop>
  146. aedsp16= [HW,OSS] Audio Excel DSP 16
  147. Format: <io>,<irq>,<dma>,<mss_io>,<mpu_io>,<mpu_irq>
  148. See also header of sound/oss/aedsp16.c.
  149. aha152x= [HW,SCSI]
  150. See Documentation/scsi/aha152x.txt.
  151. aha1542= [HW,SCSI]
  152. Format: <portbase>[,<buson>,<busoff>[,<dmaspeed>]]
  153. aic7xxx= [HW,SCSI]
  154. See Documentation/scsi/aic7xxx.txt.
  155. aic79xx= [HW,SCSI]
  156. See Documentation/scsi/aic79xx.txt.
  157. AM53C974= [HW,SCSI]
  158. Format: <host-scsi-id>,<target-scsi-id>,<max-rate>,<max-offset>
  159. See also header of drivers/scsi/AM53C974.c.
  160. amijoy.map= [HW,JOY] Amiga joystick support
  161. Map of devices attached to JOY0DAT and JOY1DAT
  162. Format: <a>,<b>
  163. See also Documentation/kernel/input/joystick.txt
  164. analog.map= [HW,JOY] Analog joystick and gamepad support
  165. Specifies type or capabilities of an analog joystick
  166. connected to one of 16 gameports
  167. Format: <type1>,<type2>,..<type16>
  168. apc= [HW,SPARC] Power management functions (SPARCstation-4/5 + deriv.)
  169. Format: noidle
  170. Disable APC CPU standby support. SPARCstation-Fox does
  171. not play well with APC CPU idle - disable it if you have
  172. APC and your system crashes randomly.
  173. apic= [APIC,i386] Change the output verbosity whilst booting
  174. Format: { quiet (default) | verbose | debug }
  175. Change the amount of debugging information output
  176. when initialising the APIC and IO-APIC components.
  177. apm= [APM] Advanced Power Management
  178. See header of arch/i386/kernel/apm.c.
  179. applicom= [HW]
  180. Format: <mem>,<irq>
  181. arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
  182. Format: <io>,<irq>,<nodeID>
  183. ataflop= [HW,M68k]
  184. atarimouse= [HW,MOUSE] Atari Mouse
  185. atascsi= [HW,SCSI] Atari SCSI
  186. atkbd.extra= [HW] Enable extra LEDs and keys on IBM RapidAccess,
  187. EzKey and similar keyboards
  188. atkbd.reset= [HW] Reset keyboard during initialization
  189. atkbd.set= [HW] Select keyboard code set
  190. Format: <int> (2 = AT (default) 3 = PS/2)
  191. atkbd.scroll= [HW] Enable scroll wheel on MS Office and similar
  192. keyboards
  193. atkbd.softraw= [HW] Choose between synthetic and real raw mode
  194. Format: <bool> (0 = real, 1 = synthetic (default))
  195. atkbd.softrepeat=
  196. [HW] Use software keyboard repeat
  197. autotest [IA64]
  198. awe= [HW,OSS] AWE32/SB32/AWE64 wave table synth
  199. Format: <io>,<memsize>,<isapnp>
  200. aztcd= [HW,CD] Aztech CD268 CDROM driver
  201. Format: <io>,0x79 (?)
  202. baycom_epp= [HW,AX25]
  203. Format: <io>,<mode>
  204. baycom_par= [HW,AX25] BayCom Parallel Port AX.25 Modem
  205. Format: <io>,<mode>
  206. See header of drivers/net/hamradio/baycom_par.c.
  207. baycom_ser_fdx= [HW,AX25] BayCom Serial Port AX.25 Modem (Full Duplex Mode)
  208. Format: <io>,<irq>,<mode>[,<baud>]
  209. See header of drivers/net/hamradio/baycom_ser_fdx.c.
  210. baycom_ser_hdx= [HW,AX25] BayCom Serial Port AX.25 Modem (Half Duplex Mode)
  211. Format: <io>,<irq>,<mode>
  212. See header of drivers/net/hamradio/baycom_ser_hdx.c.
  213. blkmtd_device= [HW,MTD]
  214. blkmtd_erasesz=
  215. blkmtd_ro=
  216. blkmtd_bs=
  217. blkmtd_count=
  218. bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards)
  219. bttv.radio= Most important insmod options are available as kernel args too.
  220. bttv.pll= See Documentation/video4linux/bttv/Insmod-options
  221. bttv.tuner= and Documentation/video4linux/bttv/CARDLIST
  222. BusLogic= [HW,SCSI]
  223. See drivers/scsi/BusLogic.c, comment before function
  224. BusLogic_ParseDriverOptions().
  225. c101= [NET] Moxa C101 synchronous serial card
  226. cachesize= [BUGS=IA-32] Override level 2 CPU cache size detection.
  227. Sometimes CPU hardware bugs make them report the cache
  228. size incorrectly. The kernel will attempt work arounds
  229. to fix known problems, but for some CPUs it is not
  230. possible to determine what the correct size should be.
  231. This option provides an override for these situations.
  232. cdu31a= [HW,CD]
  233. Format: <io>,<irq>[,PAS]
  234. See header of drivers/cdrom/cdu31a.c.
  235. chandev= [HW,NET] Generic channel device initialisation
  236. checkreqprot [SELINUX] Set initial checkreqprot flag value.
  237. Format: { "0" | "1" }
  238. See security/selinux/Kconfig help text.
  239. 0 -- check protection applied by kernel (includes any implied execute protection).
  240. 1 -- check protection requested by application.
  241. Default value is set via a kernel config option.
  242. Value can be changed at runtime via /selinux/checkreqprot.
  243. clock= [BUGS=IA-32, HW] gettimeofday timesource override.
  244. Forces specified timesource (if avaliable) to be used
  245. when calculating gettimeofday(). If specicified timesource
  246. is not avalible, it defaults to PIT.
  247. Format: { pit | tsc | cyclone | pmtmr }
  248. hpet= [IA-32,HPET] option to disable HPET and use PIT.
  249. Format: disable
  250. cm206= [HW,CD]
  251. Format: { auto | [<io>,][<irq>] }
  252. com20020= [HW,NET] ARCnet - COM20020 chipset
  253. Format: <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]]
  254. com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
  255. Format: <io>[,<irq>]
  256. com90xx= [HW,NET] ARCnet - COM90xx chipset (memory-mapped buffers)
  257. Format: <io>[,<irq>[,<memstart>]]
  258. condev= [HW,S390] console device
  259. conmode=
  260. console= [KNL] Output console device and options.
  261. tty<n> Use the virtual console device <n>.
  262. ttyS<n>[,options]
  263. Use the specified serial port. The options are of
  264. the form "bbbbpn", where "bbbb" is the baud rate,
  265. "p" is parity ("n", "o", or "e"), and "n" is bits.
  266. Default is "9600n8".
  267. See also Documentation/serial-console.txt.
  268. uart,io,<addr>[,options]
  269. uart,mmio,<addr>[,options]
  270. Start an early, polled-mode console on the 8250/16550
  271. UART at the specified I/O port or MMIO address,
  272. switching to the matching ttyS device later. The
  273. options are the same as for ttyS, above.
  274. cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver
  275. Format: <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
  276. cpia_pp= [HW,PPT]
  277. Format: { parport<nr> | auto | none }
  278. crashkernel=nn[KMG]@ss[KMG]
  279. [KNL] Reserve a chunk of physical memory to
  280. hold a kernel to switch to with kexec on panic.
  281. cs4232= [HW,OSS]
  282. Format: <io>,<irq>,<dma>,<dma2>,<mpuio>,<mpuirq>
  283. cs89x0_dma= [HW,NET]
  284. Format: <dma>
  285. cs89x0_media= [HW,NET]
  286. Format: { rj45 | aui | bnc }
  287. cyclades= [HW,SERIAL] Cyclades multi-serial port adapter.
  288. dasd= [HW,NET]
  289. See header of drivers/s390/block/dasd_devmap.c.
  290. db9.dev[2|3]= [HW,JOY] Multisystem joystick support via parallel port
  291. (one device per port)
  292. Format: <port#>,<type>
  293. See also Documentation/input/joystick-parport.txt
  294. debug [KNL] Enable kernel debugging (events log level).
  295. decnet= [HW,NET]
  296. Format: <area>[,<node>]
  297. See also Documentation/networking/decnet.txt.
  298. devfs= [DEVFS]
  299. See Documentation/filesystems/devfs/boot-options.
  300. dhash_entries= [KNL]
  301. Set number of hash buckets for dentry cache.
  302. digi= [HW,SERIAL]
  303. IO parameters + enable/disable command.
  304. digiepca= [HW,SERIAL]
  305. See drivers/char/README.epca and
  306. Documentation/digiepca.txt.
  307. dmascc= [HW,AX25,SERIAL] AX.25 Z80SCC driver with DMA
  308. support available.
  309. Format: <io_dev0>[,<io_dev1>[,..<io_dev32>]]
  310. dmasound= [HW,OSS] Sound subsystem buffers
  311. dscc4.setup= [NET]
  312. dtc3181e= [HW,SCSI]
  313. earlyprintk= [IA-32, X86-64]
  314. earlyprintk=vga
  315. earlyprintk=serial[,ttySn[,baudrate]]
  316. Append ,keep to not disable it when the real console
  317. takes over.
  318. Only vga or serial at a time, not both.
  319. Currently only ttyS0 and ttyS1 are supported.
  320. Interaction with the standard serial driver is not
  321. very good.
  322. The VGA output is eventually overwritten by the real
  323. console.
  324. eata= [HW,SCSI]
  325. eda= [HW,PS2]
  326. edb= [HW,PS2]
  327. edd= [EDD]
  328. Format: {"of[f]" | "sk[ipmbr]"}
  329. See comment in arch/i386/boot/edd.S
  330. eicon= [HW,ISDN]
  331. Format: <id>,<membase>,<irq>
  332. eisa_irq_edge= [PARISC,HW]
  333. See header of drivers/parisc/eisa.c.
  334. elanfreq= [IA-32]
  335. See comment before function elanfreq_setup() in
  336. arch/i386/kernel/cpu/cpufreq/elanfreq.c.
  337. elevator= [IOSCHED]
  338. Format: {"as"|"cfq"|"deadline"|"noop"}
  339. See Documentation/block/as-iosched.txt
  340. and Documentation/block/deadline-iosched.txt for details.
  341. elfcorehdr= [IA-32]
  342. Specifies physical address of start of kernel core image
  343. elf header.
  344. See Documentation/kdump.txt for details.
  345. enforcing [SELINUX] Set initial enforcing status.
  346. Format: {"0" | "1"}
  347. See security/selinux/Kconfig help text.
  348. 0 -- permissive (log only, no denials).
  349. 1 -- enforcing (deny and log).
  350. Default value is 0.
  351. Value can be changed at runtime via /selinux/enforce.
  352. es1370= [HW,OSS]
  353. Format: <lineout>[,<micbias>]
  354. See also header of sound/oss/es1370.c.
  355. es1371= [HW,OSS]
  356. Format: <spdif>,[<nomix>,[<amplifier>]]
  357. See also header of sound/oss/es1371.c.
  358. ether= [HW,NET] Ethernet cards parameters
  359. This option is obsoleted by the "netdev=" option, which
  360. has equivalent usage. See its documentation for details.
  361. eurwdt= [HW,WDT] Eurotech CPU-1220/1410 onboard watchdog.
  362. Format: <io>[,<irq>]
  363. fd_mcs= [HW,SCSI]
  364. See header of drivers/scsi/fd_mcs.c.
  365. fdomain= [HW,SCSI]
  366. See header of drivers/scsi/fdomain.c.
  367. floppy= [HW]
  368. See Documentation/floppy.txt.
  369. ftape= [HW] Floppy Tape subsystem debugging options.
  370. See Documentation/ftape.txt.
  371. gamecon.map[2|3]=
  372. [HW,JOY] Multisystem joystick and NES/SNES/PSX pad
  373. support via parallel port (up to 5 devices per port)
  374. Format: <port#>,<pad1>,<pad2>,<pad3>,<pad4>,<pad5>
  375. See also Documentation/input/joystick-parport.txt
  376. gamma= [HW,DRM]
  377. gdth= [HW,SCSI]
  378. See header of drivers/scsi/gdth.c.
  379. gpt [EFI] Forces disk with valid GPT signature but
  380. invalid Protective MBR to be treated as GPT.
  381. gscd= [HW,CD]
  382. Format: <io>
  383. gt96100eth= [NET] MIPS GT96100 Advanced Communication Controller
  384. gus= [HW,OSS]
  385. Format: <io>,<irq>,<dma>,<dma16>
  386. gvp11= [HW,SCSI]
  387. hashdist= [KNL,NUMA] Large hashes allocated during boot
  388. are distributed across NUMA nodes. Defaults on
  389. for IA-64, off otherwise.
  390. hcl= [IA-64] SGI's Hardware Graph compatibility layer
  391. hd= [EIDE] (E)IDE hard drive subsystem geometry
  392. Format: <cyl>,<head>,<sect>
  393. hd?= [HW] (E)IDE subsystem
  394. hd?lun= See Documentation/ide.txt.
  395. highmem=nn[KMG] [KNL,BOOT] forces the highmem zone to have an exact
  396. size of <nn>. This works even on boxes that have no
  397. highmem otherwise. This also works to reduce highmem
  398. size on bigger boxes.
  399. hisax= [HW,ISDN]
  400. See Documentation/isdn/README.HiSax.
  401. hugepages= [HW,IA-32,IA-64] Maximal number of HugeTLB pages.
  402. noirqbalance [IA-32,SMP,KNL] Disable kernel irq balancing
  403. i8042.direct [HW] Put keyboard port into non-translated mode
  404. i8042.dumbkbd [HW] Pretend that controlled can only read data from
  405. keyboard and can not control its state
  406. (Don't attempt to blink the leds)
  407. i8042.noaux [HW] Don't check for auxiliary (== mouse) port
  408. i8042.nomux [HW] Don't check presence of an active multiplexing
  409. controller
  410. i8042.nopnp [HW] Don't use ACPIPnP / PnPBIOS to discover KBD/AUX
  411. controllers
  412. i8042.panicblink=
  413. [HW] Frequency with which keyboard LEDs should blink
  414. when kernel panics (default is 0.5 sec)
  415. i8042.reset [HW] Reset the controller during init and cleanup
  416. i8042.unlock [HW] Unlock (ignore) the keylock
  417. i810= [HW,DRM]
  418. i8k.ignore_dmi [HW] Continue probing hardware even if DMI data
  419. indicates that the driver is running on unsupported
  420. hardware.
  421. i8k.force [HW] Activate i8k driver even if SMM BIOS signature
  422. does not match list of supported models.
  423. i8k.power_status
  424. [HW] Report power status in /proc/i8k
  425. (disabled by default)
  426. i8k.restricted [HW] Allow controlling fans only if SYS_ADMIN
  427. capability is set.
  428. ibmmcascsi= [HW,MCA,SCSI] IBM MicroChannel SCSI adapter
  429. See Documentation/mca.txt.
  430. icn= [HW,ISDN]
  431. Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]]
  432. ide= [HW] (E)IDE subsystem
  433. Format: ide=nodma or ide=doubler or ide=reverse
  434. See Documentation/ide.txt.
  435. ide?= [HW] (E)IDE subsystem
  436. Format: ide?=noprobe or chipset specific parameters.
  437. See Documentation/ide.txt.
  438. idebus= [HW] (E)IDE subsystem - VLB/PCI bus speed
  439. See Documentation/ide.txt.
  440. idle= [HW]
  441. Format: idle=poll or idle=halt
  442. ihash_entries= [KNL]
  443. Set number of hash buckets for inode cache.
  444. in2000= [HW,SCSI]
  445. See header of drivers/scsi/in2000.c.
  446. init= [KNL]
  447. Format: <full_path>
  448. Run specified binary instead of /sbin/init as init
  449. process.
  450. initcall_debug [KNL] Trace initcalls as they are executed. Useful
  451. for working out where the kernel is dying during
  452. startup.
  453. initrd= [BOOT] Specify the location of the initial ramdisk
  454. inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver
  455. Format: <irq>
  456. inttest= [IA64]
  457. io7= [HW] IO7 for Marvel based alpha systems
  458. See comment before marvel_specify_io7 in
  459. arch/alpha/kernel/core_marvel.c.
  460. ip= [IP_PNP]
  461. See Documentation/nfsroot.txt.
  462. ip2= [HW] Set IO/IRQ pairs for up to 4 IntelliPort boards
  463. See comment before ip2_setup() in drivers/char/ip2.c.
  464. ips= [HW,SCSI] Adaptec / IBM ServeRAID controller
  465. See header of drivers/scsi/ips.c.
  466. irqfixup [HW]
  467. When an interrupt is not handled search all handlers
  468. for it. Intended to get systems with badly broken
  469. firmware running.
  470. irqpoll [HW]
  471. When an interrupt is not handled search all handlers
  472. for it. Also check all handlers each timer
  473. interrupt. Intended to get systems with badly broken
  474. firmware running.
  475. isapnp= [ISAPNP]
  476. Format: <RDP>, <reset>, <pci_scan>, <verbosity>
  477. isolcpus= [KNL,SMP] Isolate CPUs from the general scheduler.
  478. Format: <cpu number>,...,<cpu number>
  479. This option can be used to specify one or more CPUs
  480. to isolate from the general SMP balancing and scheduling
  481. algorithms. The only way to move a process onto or off
  482. an "isolated" CPU is via the CPU affinity syscalls.
  483. <cpu number> begins at 0 and the maximum value is
  484. "number of CPUs in system - 1".
  485. This option is the preferred way to isolate CPUs. The
  486. alternative - manually setting the CPU mask of all tasks
  487. in the system can cause problems and suboptimal load
  488. balancer performance.
  489. isp16= [HW,CD]
  490. Format: <io>,<irq>,<dma>,<setup>
  491. iucv= [HW,NET]
  492. js= [HW,JOY] Analog joystick
  493. See Documentation/input/joystick.txt.
  494. keepinitrd [HW,ARM]
  495. kstack=N [IA-32, X86-64] Print N words from the kernel stack
  496. in oops dumps.
  497. l2cr= [PPC]
  498. lapic [IA-32,APIC] Enable the local APIC even if BIOS disabled it.
  499. lasi= [HW,SCSI] PARISC LASI driver for the 53c700 chip
  500. Format: addr:<io>,irq:<irq>
  501. llsc*= [IA64]
  502. See function print_params() in arch/ia64/sn/kernel/llsc4.c.
  503. load_ramdisk= [RAM] List of ramdisks to load from floppy
  504. See Documentation/ramdisk.txt.
  505. lockd.udpport= [NFS]
  506. lockd.tcpport= [NFS]
  507. logibm.irq= [HW,MOUSE] Logitech Bus Mouse Driver
  508. Format: <irq>
  509. loglevel= All Kernel Messages with a loglevel smaller than the
  510. console loglevel will be printed to the console. It can
  511. also be changed with klogd or other programs. The
  512. loglevels are defined as follows:
  513. 0 (KERN_EMERG) system is unusable
  514. 1 (KERN_ALERT) action must be taken immediately
  515. 2 (KERN_CRIT) critical conditions
  516. 3 (KERN_ERR) error conditions
  517. 4 (KERN_WARNING) warning conditions
  518. 5 (KERN_NOTICE) normal but significant condition
  519. 6 (KERN_INFO) informational
  520. 7 (KERN_DEBUG) debug-level messages
  521. log_buf_len=n Sets the size of the printk ring buffer, in bytes.
  522. Format is n, nk, nM. n must be a power of two. The
  523. default is set in kernel config.
  524. lp=0 [LP] Specify parallel ports to use, e.g,
  525. lp=port[,port...] lp=none,parport0 (lp0 not configured, lp1 uses
  526. lp=reset first parallel port). 'lp=0' disables the
  527. lp=auto printer driver. 'lp=reset' (which can be
  528. specified in addition to the ports) causes
  529. attached printers to be reset. Using
  530. lp=port1,port2,... specifies the parallel ports
  531. to associate lp devices with, starting with
  532. lp0. A port specification may be 'none' to skip
  533. that lp device, or a parport name such as
  534. 'parport0'. Specifying 'lp=auto' instead of a
  535. port specification list means that device IDs
  536. from each port should be examined, to see if
  537. an IEEE 1284-compliant printer is attached; if
  538. so, the driver will manage that printer.
  539. See also header of drivers/char/lp.c.
  540. lpj=n [KNL]
  541. Sets loops_per_jiffy to given constant, thus avoiding
  542. time-consuming boot-time autodetection (up to 250 ms per
  543. CPU). 0 enables autodetection (default). To determine
  544. the correct value for your kernel, boot with normal
  545. autodetection and see what value is printed. Note that
  546. on SMP systems the preset will be applied to all CPUs,
  547. which is likely to cause problems if your CPUs need
  548. significantly divergent settings. An incorrect value
  549. will cause delays in the kernel to be wrong, leading to
  550. unpredictable I/O errors and other breakage. Although
  551. unlikely, in the extreme case this might damage your
  552. hardware.
  553. ltpc= [NET]
  554. Format: <io>,<irq>,<dma>
  555. mac5380= [HW,SCSI]
  556. Format: <can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
  557. mac53c9x= [HW,SCSI]
  558. Format: <num_esps>,<disconnect>,<nosync>,<can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
  559. machvec= [IA64]
  560. Force the use of a particular machine-vector (machvec) in a generic
  561. kernel. Example: machvec=hpzx1_swiotlb
  562. mad16= [HW,OSS]
  563. Format: <io>,<irq>,<dma>,<dma16>,<mpu_io>,<mpu_irq>,<joystick>
  564. maui= [HW,OSS]
  565. Format: <io>,<irq>
  566. max_loop= [LOOP] Maximum number of loopback devices that can
  567. be mounted
  568. Format: <1-256>
  569. maxcpus= [SMP] Maximum number of processors that an SMP kernel
  570. should make use of
  571. max_luns= [SCSI] Maximum number of LUNs to probe
  572. Should be between 1 and 2^32-1.
  573. max_report_luns=
  574. [SCSI] Maximum number of LUNs received
  575. Should be between 1 and 16384.
  576. mca-pentium [BUGS=IA-32]
  577. mcatest= [IA-64]
  578. mcd= [HW,CD]
  579. Format: <port>,<irq>,<mitsumi_bug_93_wait>
  580. mcdx= [HW,CD]
  581. mce [IA-32] Machine Check Exception
  582. md= [HW] RAID subsystems devices and level
  583. See Documentation/md.txt.
  584. mdacon= [MDA]
  585. Format: <first>,<last>
  586. Specifies range of consoles to be captured by the MDA.
  587. mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory
  588. Amount of memory to be used when the kernel is not able
  589. to see the whole system memory or for test.
  590. [IA-32] Use together with memmap= to avoid physical
  591. address space collisions. Without memmap= PCI devices
  592. could be placed at addresses belonging to unused RAM.
  593. mem=nopentium [BUGS=IA-32] Disable usage of 4MB pages for kernel
  594. memory.
  595. memmap=exactmap [KNL,IA-32] Enable setting of an exact
  596. E820 memory map, as specified by the user.
  597. Such memmap=exactmap lines can be constructed based on
  598. BIOS output or other requirements. See the memmap=nn@ss
  599. option description.
  600. memmap=nn[KMG]@ss[KMG]
  601. [KNL] Force usage of a specific region of memory
  602. Region of memory to be used, from ss to ss+nn.
  603. memmap=nn[KMG]#ss[KMG]
  604. [KNL,ACPI] Mark specific memory as ACPI data.
  605. Region of memory to be used, from ss to ss+nn.
  606. memmap=nn[KMG]$ss[KMG]
  607. [KNL,ACPI] Mark specific memory as reserved.
  608. Region of memory to be used, from ss to ss+nn.
  609. meye.*= [HW] Set MotionEye Camera parameters
  610. See Documentation/video4linux/meye.txt.
  611. mga= [HW,DRM]
  612. mousedev.tap_time=
  613. [MOUSE] Maximum time between finger touching and
  614. leaving touchpad surface for touch to be considered
  615. a tap and be reported as a left button click (for
  616. touchpads working in absolute mode only).
  617. Format: <msecs>
  618. mousedev.xres= [MOUSE] Horizontal screen resolution, used for devices
  619. reporting absolute coordinates, such as tablets
  620. mousedev.yres= [MOUSE] Vertical screen resolution, used for devices
  621. reporting absolute coordinates, such as tablets
  622. mpu401= [HW,OSS]
  623. Format: <io>,<irq>
  624. MTD_Partition= [MTD]
  625. Format: <name>,<region-number>,<size>,<offset>
  626. MTD_Region= [MTD]
  627. Format: <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
  628. mtdparts= [MTD]
  629. See drivers/mtd/cmdline.c.
  630. mtouchusb.raw_coordinates=
  631. [HW] Make the MicroTouch USB driver use raw coordinates ('y', default)
  632. or cooked coordinates ('n')
  633. n2= [NET] SDL Inc. RISCom/N2 synchronous serial card
  634. NCR_D700= [HW,SCSI]
  635. See header of drivers/scsi/NCR_D700.c.
  636. ncr5380= [HW,SCSI]
  637. ncr53c400= [HW,SCSI]
  638. ncr53c400a= [HW,SCSI]
  639. ncr53c406a= [HW,SCSI]
  640. ncr53c8xx= [HW,SCSI]
  641. netdev= [NET] Network devices parameters
  642. Format: <irq>,<io>,<mem_start>,<mem_end>,<name>
  643. Note that mem_start is often overloaded to mean
  644. something different and driver-specific.
  645. nfsaddrs= [NFS]
  646. See Documentation/nfsroot.txt.
  647. nfsroot= [NFS] nfs root filesystem for disk-less boxes.
  648. See Documentation/nfsroot.txt.
  649. nmi_watchdog= [KNL,BUGS=IA-32] Debugging features for SMP kernels
  650. no387 [BUGS=IA-32] Tells the kernel to use the 387 maths
  651. emulation library even if a 387 maths coprocessor
  652. is present.
  653. noalign [KNL,ARM]
  654. noapic [SMP,APIC] Tells the kernel to not make use of any
  655. IOAPICs that may be present in the system.
  656. noasync [HW,M68K] Disables async and sync negotiation for
  657. all devices.
  658. nobats [PPC] Do not use BATs for mapping kernel lowmem
  659. on "Classic" PPC cores.
  660. nocache [ARM]
  661. nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects.
  662. noexec [IA-64]
  663. noexec [IA-32, X86-64]
  664. noexec=on: enable non-executable mappings (default)
  665. noexec=off: disable nn-executable mappings
  666. nofxsr [BUGS=IA-32]
  667. nohlt [BUGS=ARM]
  668. no-hlt [BUGS=IA-32] Tells the kernel that the hlt
  669. instruction doesn't work correctly and not to
  670. use it.
  671. nohalt [IA-64] Tells the kernel not to use the power saving
  672. function PAL_HALT_LIGHT when idle. This increases
  673. power-consumption. On the positive side, it reduces
  674. interrupt wake-up latency, which may improve performance
  675. in certain environments such as networked servers or
  676. real-time systems.
  677. noirqdebug [IA-32] Disables the code which attempts to detect and
  678. disable unhandled interrupt sources.
  679. noisapnp [ISAPNP] Disables ISA PnP code.
  680. noinitrd [RAM] Tells the kernel not to load any configured
  681. initial RAM disk.
  682. nointroute [IA-64]
  683. nolapic [IA-32,APIC] Do not enable or use the local APIC.
  684. noltlbs [PPC] Do not use large page/tlb entries for kernel
  685. lowmem mapping on PPC40x.
  686. nomce [IA-32] Machine Check Exception
  687. noresidual [PPC] Don't use residual data on PReP machines.
  688. noresume [SWSUSP] Disables resume and restore original swap space.
  689. no-scroll [VGA] Disables scrollback.
  690. This is required for the Braillex ib80-piezo Braille
  691. reader made by F.H. Papenmeier (Germany).
  692. nosbagart [IA-64]
  693. nosmp [SMP] Tells an SMP kernel to act as a UP kernel.
  694. nosync [HW,M68K] Disables sync negotiation for all devices.
  695. notsc [BUGS=IA-32] Disable Time Stamp Counter
  696. nousb [USB] Disable the USB subsystem
  697. nowb [ARM]
  698. opl3= [HW,OSS]
  699. Format: <io>
  700. opl3sa= [HW,OSS]
  701. Format: <io>,<irq>,<dma>,<dma2>,<mpu_io>,<mpu_irq>
  702. opl3sa2= [HW,OSS]
  703. Format: <io>,<irq>,<dma>,<dma2>,<mss_io>,<mpu_io>,<ymode>,<loopback>[,<isapnp>,<multiple]
  704. oprofile.timer= [HW]
  705. Use timer interrupt instead of performance counters
  706. optcd= [HW,CD]
  707. Format: <io>
  708. osst= [HW,SCSI] SCSI Tape Driver
  709. Format: <buffer_size>,<write_threshold>
  710. See also Documentation/scsi/st.txt.
  711. panic= [KNL] Kernel behaviour on panic
  712. Format: <timeout>
  713. parkbd.port= [HW] Parallel port number the keyboard adapter is
  714. connected to, default is 0.
  715. Format: <parport#>
  716. parkbd.mode= [HW] Parallel port keyboard adapter mode of operation,
  717. 0 for XT, 1 for AT (default is AT).
  718. Format: <mode>
  719. parport=0 [HW,PPT] Specify parallel ports. 0 disables.
  720. parport=auto Use 'auto' to force the driver to use
  721. parport=0xBBB[,IRQ[,DMA]] any IRQ/DMA settings detected (the
  722. default is to ignore detected IRQ/DMA
  723. settings because of possible
  724. conflicts). You can specify the base
  725. address, IRQ, and DMA settings; IRQ and
  726. DMA should be numbers, or 'auto' (for
  727. using detected settings on that
  728. particular port), or 'nofifo' (to avoid
  729. using a FIFO even if it is detected).
  730. Parallel ports are assigned in the
  731. order they are specified on the command
  732. line, starting with parport0.
  733. parport_init_mode=
  734. [HW,PPT] Configure VIA parallel port to
  735. operate in specific mode. This is
  736. necessary on Pegasos computer where
  737. firmware has no options for setting up
  738. parallel port mode and sets it to
  739. spp. Currently this function knows
  740. 686a and 8231 chips.
  741. Format: [spp|ps2|epp|ecp|ecpepp]
  742. pas2= [HW,OSS]
  743. Format: <io>,<irq>,<dma>,<dma16>,<sb_io>,<sb_irq>,<sb_dma>,<sb_dma16>
  744. pas16= [HW,SCSI]
  745. See header of drivers/scsi/pas16.c.
  746. pcbit= [HW,ISDN]
  747. pcd. [PARIDE]
  748. See header of drivers/block/paride/pcd.c.
  749. See also Documentation/paride.txt.
  750. pci=option[,option...] [PCI] various PCI subsystem options:
  751. off [IA-32] don't probe for the PCI bus
  752. bios [IA-32] force use of PCI BIOS, don't access
  753. the hardware directly. Use this if your machine
  754. has a non-standard PCI host bridge.
  755. nobios [IA-32] disallow use of PCI BIOS, only direct
  756. hardware access methods are allowed. Use this
  757. if you experience crashes upon bootup and you
  758. suspect they are caused by the BIOS.
  759. conf1 [IA-32] Force use of PCI Configuration Mechanism 1.
  760. conf2 [IA-32] Force use of PCI Configuration Mechanism 2.
  761. nosort [IA-32] Don't sort PCI devices according to
  762. order given by the PCI BIOS. This sorting is done
  763. to get a device order compatible with older kernels.
  764. biosirq [IA-32] Use PCI BIOS calls to get the interrupt
  765. routing table. These calls are known to be buggy
  766. on several machines and they hang the machine when used,
  767. but on other computers it's the only way to get the
  768. interrupt routing table. Try this option if the kernel
  769. is unable to allocate IRQs or discover secondary PCI
  770. buses on your motherboard.
  771. rom [IA-32] Assign address space to expansion ROMs.
  772. Use with caution as certain devices share address
  773. decoders between ROMs and other resources.
  774. irqmask=0xMMMM [IA-32] Set a bit mask of IRQs allowed to be assigned
  775. automatically to PCI devices. You can make the kernel
  776. exclude IRQs of your ISA cards this way.
  777. pirqaddr=0xAAAAA [IA-32] Specify the physical address
  778. of the PIRQ table (normally generated
  779. by the BIOS) if it is outside the
  780. F0000h-100000h range.
  781. lastbus=N [IA-32] Scan all buses till bus #N. Can be useful
  782. if the kernel is unable to find your secondary buses
  783. and you want to tell it explicitly which ones they are.
  784. assign-busses [IA-32] Always assign all PCI bus
  785. numbers ourselves, overriding
  786. whatever the firmware may have
  787. done.
  788. usepirqmask [IA-32] Honor the possible IRQ mask
  789. stored in the BIOS $PIR table. This is
  790. needed on some systems with broken
  791. BIOSes, notably some HP Pavilion N5400
  792. and Omnibook XE3 notebooks. This will
  793. have no effect if ACPI IRQ routing is
  794. enabled.
  795. noacpi [IA-32] Do not use ACPI for IRQ routing
  796. or for PCI scanning.
  797. routeirq Do IRQ routing for all PCI devices.
  798. This is normally done in pci_enable_device(),
  799. so this option is a temporary workaround
  800. for broken drivers that don't call it.
  801. firmware [ARM] Do not re-enumerate the bus but
  802. instead just use the configuration
  803. from the bootloader. This is currently
  804. used on IXP2000 systems where the
  805. bus has to be configured a certain way
  806. for adjunct CPUs.
  807. pcmv= [HW,PCMCIA] BadgePAD 4
  808. pd. [PARIDE]
  809. See Documentation/paride.txt.
  810. pdcchassis= [PARISC,HW] Disable/Enable PDC Chassis Status codes at
  811. boot time.
  812. Format: { 0 | 1 }
  813. See arch/parisc/kernel/pdc_chassis.c
  814. pf. [PARIDE]
  815. See Documentation/paride.txt.
  816. pg. [PARIDE]
  817. See Documentation/paride.txt.
  818. pirq= [SMP,APIC] Manual mp-table setup
  819. See Documentation/i386/IO-APIC.txt.
  820. plip= [PPT,NET] Parallel port network link
  821. Format: { parport<nr> | timid | 0 }
  822. See also Documentation/parport.txt.
  823. pnpacpi= [ACPI]
  824. { off }
  825. pnpbios= [ISAPNP]
  826. { on | off | curr | res | no-curr | no-res }
  827. pnp_reserve_irq=
  828. [ISAPNP] Exclude IRQs for the autoconfiguration
  829. pnp_reserve_dma=
  830. [ISAPNP] Exclude DMAs for the autoconfiguration
  831. pnp_reserve_io= [ISAPNP] Exclude I/O ports for the autoconfiguration
  832. Ranges are in pairs (I/O port base and size).
  833. pnp_reserve_mem=
  834. [ISAPNP] Exclude memory regions for the autoconfiguration
  835. Ranges are in pairs (memory base and size).
  836. profile= [KNL] Enable kernel profiling via /proc/profile
  837. { schedule | <number> }
  838. (param: schedule - profile schedule points}
  839. (param: profile step/bucket size as a power of 2 for
  840. statistical time based profiling)
  841. processor.max_cstate= [HW, ACPI]
  842. Limit processor to maximum C-state
  843. max_cstate=9 overrides any DMI blacklist limit.
  844. prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk
  845. before loading.
  846. See Documentation/ramdisk.txt.
  847. psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to
  848. probe for (bare|imps|exps|lifebook|any).
  849. psmouse.rate= [HW,MOUSE] Set desired mouse report rate, in reports
  850. per second.
  851. psmouse.resetafter=
  852. [HW,MOUSE] Try to reset the device after so many bad packets
  853. (0 = never).
  854. psmouse.resolution=
  855. [HW,MOUSE] Set desired mouse resolution, in dpi.
  856. psmouse.smartscroll=
  857. [HW,MOUSE] Controls Logitech smartscroll autorepeat,
  858. 0 = disabled, 1 = enabled (default).
  859. pss= [HW,OSS] Personal Sound System (ECHO ESC614)
  860. Format: <io>,<mss_io>,<mss_irq>,<mss_dma>,<mpu_io>,<mpu_irq>
  861. pt. [PARIDE]
  862. See Documentation/paride.txt.
  863. quiet= [KNL] Disable log messages
  864. r128= [HW,DRM]
  865. raid= [HW,RAID]
  866. See Documentation/md.txt.
  867. ramdisk= [RAM] Sizes of RAM disks in kilobytes [deprecated]
  868. See Documentation/ramdisk.txt.
  869. ramdisk_blocksize=
  870. [RAM]
  871. See Documentation/ramdisk.txt.
  872. ramdisk_size= [RAM] Sizes of RAM disks in kilobytes
  873. New name for the ramdisk parameter.
  874. See Documentation/ramdisk.txt.
  875. reboot= [BUGS=IA-32,BUGS=ARM,BUGS=IA-64] Rebooting mode
  876. Format: <reboot_mode>[,<reboot_mode2>[,...]]
  877. See arch/*/kernel/reboot.c.
  878. reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
  879. resume= [SWSUSP] Specify the partition device for software suspension
  880. rhash_entries= [KNL,NET]
  881. Set number of hash buckets for route cache
  882. riscom8= [HW,SERIAL]
  883. Format: <io_board1>[,<io_board2>[,...<io_boardN>]]
  884. ro [KNL] Mount root device read-only on boot
  885. root= [KNL] Root filesystem
  886. rootdelay= [KNL] Delay (in seconds) to pause before attempting to
  887. mount the root filesystem
  888. rootflags= [KNL] Set root filesystem mount option string
  889. rootfstype= [KNL] Set root filesystem type
  890. rw [KNL] Mount root device read-write on boot
  891. S [KNL] Run init in single mode
  892. sa1100ir [NET]
  893. See drivers/net/irda/sa1100_ir.c.
  894. sb= [HW,OSS]
  895. Format: <io>,<irq>,<dma>,<dma2>
  896. sbni= [NET] Granch SBNI12 leased line adapter
  897. sbpcd= [HW,CD] Soundblaster CD adapter
  898. Format: <io>,<type>
  899. See a comment before function sbpcd_setup() in
  900. drivers/cdrom/sbpcd.c.
  901. sc1200wdt= [HW,WDT] SC1200 WDT (watchdog) driver
  902. Format: <io>[,<timeout>[,<isapnp>]]
  903. scsi_debug_*= [SCSI]
  904. See drivers/scsi/scsi_debug.c.
  905. scsi_default_dev_flags=
  906. [SCSI] SCSI default device flags
  907. Format: <integer>
  908. scsi_dev_flags= [SCSI] Black/white list entry for vendor and model
  909. Format: <vendor>:<model>:<flags>
  910. (flags are integer value)
  911. scsi_logging= [SCSI]
  912. selinux [SELINUX] Disable or enable SELinux at boot time.
  913. Format: { "0" | "1" }
  914. See security/selinux/Kconfig help text.
  915. 0 -- disable.
  916. 1 -- enable.
  917. Default value is set via kernel config option.
  918. If enabled at boot time, /selinux/disable can be used
  919. later to disable prior to initial policy load.
  920. serialnumber [BUGS=IA-32]
  921. sg_def_reserved_size=
  922. [SCSI]
  923. sgalaxy= [HW,OSS]
  924. Format: <io>,<irq>,<dma>,<dma2>,<sgbase>
  925. shapers= [NET]
  926. Maximal number of shapers.
  927. sim710= [SCSI,HW]
  928. See header of drivers/scsi/sim710.c.
  929. simeth= [IA-64]
  930. simscsi=
  931. sjcd= [HW,CD]
  932. Format: <io>,<irq>,<dma>
  933. See header of drivers/cdrom/sjcd.c.
  934. slram= [HW,MTD]
  935. smart2= [HW]
  936. Format: <io1>[,<io2>[,...,<io8>]]
  937. snd-ad1816a= [HW,ALSA]
  938. snd-ad1848= [HW,ALSA]
  939. snd-ali5451= [HW,ALSA]
  940. snd-als100= [HW,ALSA]
  941. snd-als4000= [HW,ALSA]
  942. snd-azt2320= [HW,ALSA]
  943. snd-cmi8330= [HW,ALSA]
  944. snd-cmipci= [HW,ALSA]
  945. snd-cs4231= [HW,ALSA]
  946. snd-cs4232= [HW,ALSA]
  947. snd-cs4236= [HW,ALSA]
  948. snd-cs4281= [HW,ALSA]
  949. snd-cs46xx= [HW,ALSA]
  950. snd-dt019x= [HW,ALSA]
  951. snd-dummy= [HW,ALSA]
  952. snd-emu10k1= [HW,ALSA]
  953. snd-ens1370= [HW,ALSA]
  954. snd-ens1371= [HW,ALSA]
  955. snd-es968= [HW,ALSA]
  956. snd-es1688= [HW,ALSA]
  957. snd-es18xx= [HW,ALSA]
  958. snd-es1938= [HW,ALSA]
  959. snd-es1968= [HW,ALSA]
  960. snd-fm801= [HW,ALSA]
  961. snd-gusclassic= [HW,ALSA]
  962. snd-gusextreme= [HW,ALSA]
  963. snd-gusmax= [HW,ALSA]
  964. snd-hdsp= [HW,ALSA]
  965. snd-ice1712= [HW,ALSA]
  966. snd-intel8x0= [HW,ALSA]
  967. snd-interwave= [HW,ALSA]
  968. snd-interwave-stb=
  969. [HW,ALSA]
  970. snd-korg1212= [HW,ALSA]
  971. snd-maestro3= [HW,ALSA]
  972. snd-mpu401= [HW,ALSA]
  973. snd-mtpav= [HW,ALSA]
  974. snd-nm256= [HW,ALSA]
  975. snd-opl3sa2= [HW,ALSA]
  976. snd-opti92x-ad1848=
  977. [HW,ALSA]
  978. snd-opti92x-cs4231=
  979. [HW,ALSA]
  980. snd-opti93x= [HW,ALSA]
  981. snd-pmac= [HW,ALSA]
  982. snd-rme32= [HW,ALSA]
  983. snd-rme96= [HW,ALSA]
  984. snd-rme9652= [HW,ALSA]
  985. snd-sb8= [HW,ALSA]
  986. snd-sb16= [HW,ALSA]
  987. snd-sbawe= [HW,ALSA]
  988. snd-serial= [HW,ALSA]
  989. snd-sgalaxy= [HW,ALSA]
  990. snd-sonicvibes= [HW,ALSA]
  991. snd-sun-amd7930=
  992. [HW,ALSA]
  993. snd-sun-cs4231= [HW,ALSA]
  994. snd-trident= [HW,ALSA]
  995. snd-usb-audio= [HW,ALSA,USB]
  996. snd-via82xx= [HW,ALSA]
  997. snd-virmidi= [HW,ALSA]
  998. snd-wavefront= [HW,ALSA]
  999. snd-ymfpci= [HW,ALSA]
  1000. sonicvibes= [HW,OSS]
  1001. Format: <reverb>
  1002. sonycd535= [HW,CD]
  1003. Format: <io>[,<irq>]
  1004. sonypi.*= [HW] Sony Programmable I/O Control Device driver
  1005. See Documentation/sonypi.txt
  1006. specialix= [HW,SERIAL] Specialix multi-serial port adapter
  1007. See Documentation/specialix.txt.
  1008. spia_io_base= [HW,MTD]
  1009. spia_fio_base=
  1010. spia_pedr=
  1011. spia_peddr=
  1012. sscape= [HW,OSS]
  1013. Format: <io>,<irq>,<dma>,<mpu_io>,<mpu_irq>
  1014. st= [HW,SCSI] SCSI tape parameters (buffers, etc.)
  1015. See Documentation/scsi/st.txt.
  1016. st0x= [HW,SCSI]
  1017. See header of drivers/scsi/seagate.c.
  1018. sti= [PARISC,HW]
  1019. Format: <num>
  1020. Set the STI (builtin display/keyboard on the HP-PARISC
  1021. machines) console (graphic card) which should be used
  1022. as the initial boot-console.
  1023. See also comment in drivers/video/console/sticore.c.
  1024. sti_font= [HW]
  1025. See comment in drivers/video/console/sticore.c.
  1026. stifb= [HW]
  1027. Format: bpp:<bpp1>[:<bpp2>[:<bpp3>...]]
  1028. stram_swap= [HW,M68k]
  1029. swiotlb= [IA-64] Number of I/O TLB slabs
  1030. switches= [HW,M68k]
  1031. sym53c416= [HW,SCSI]
  1032. See header of drivers/scsi/sym53c416.c.
  1033. t128= [HW,SCSI]
  1034. See header of drivers/scsi/t128.c.
  1035. tdfx= [HW,DRM]
  1036. thash_entries= [KNL,NET]
  1037. Set number of hash buckets for TCP connection
  1038. time Show timing data prefixed to each printk message line
  1039. tipar.timeout= [HW,PPT]
  1040. Set communications timeout in tenths of a second
  1041. (default 15).
  1042. tipar.delay= [HW,PPT]
  1043. Set inter-bit delay in microseconds (default 10).
  1044. tmc8xx= [HW,SCSI]
  1045. See header of drivers/scsi/seagate.c.
  1046. tmscsim= [HW,SCSI]
  1047. See comment before function dc390_setup() in
  1048. drivers/scsi/tmscsim.c.
  1049. tp720= [HW,PS2]
  1050. trix= [HW,OSS] MediaTrix AudioTrix Pro
  1051. Format: <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq>
  1052. tsdev.xres= [TS] Horizontal screen resolution.
  1053. tsdev.yres= [TS] Vertical screen resolution.
  1054. turbografx.map[2|3]=
  1055. [HW,JOY] TurboGraFX parallel port interface
  1056. Format: <port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7>
  1057. See also Documentation/input/joystick-parport.txt
  1058. u14-34f= [HW,SCSI] UltraStor 14F/34F SCSI host adapter
  1059. See header of drivers/scsi/u14-34f.c.
  1060. uart401= [HW,OSS]
  1061. Format: <io>,<irq>
  1062. uart6850= [HW,OSS]
  1063. Format: <io>,<irq>
  1064. usb-handoff [HW] Enable early USB BIOS -> OS handoff
  1065. usbhid.mousepoll=
  1066. [USBHID] The interval which mice are to be polled at.
  1067. video= [FB] Frame buffer configuration
  1068. See Documentation/fb/modedb.txt.
  1069. vga= [BOOT,IA-32] Select a particular video mode
  1070. See Documentation/i386/boot.txt and Documentation/svga.txt.
  1071. Use vga=ask for menu.
  1072. This is actually a boot loader parameter; the value is
  1073. passed to the kernel using a special protocol.
  1074. vmalloc=nn[KMG] [KNL,BOOT] forces the vmalloc area to have an exact
  1075. size of <nn>. This can be used to increase the
  1076. minimum size (128MB on x86). It can also be used to
  1077. decrease the size and leave more room for directly
  1078. mapped kernel RAM.
  1079. vmhalt= [KNL,S390]
  1080. vmpoff= [KNL,S390]
  1081. waveartist= [HW,OSS]
  1082. Format: <io>,<irq>,<dma>,<dma2>
  1083. wd33c93= [HW,SCSI]
  1084. See header of drivers/scsi/wd33c93.c.
  1085. wd7000= [HW,SCSI]
  1086. See header of drivers/scsi/wd7000.c.
  1087. wdt= [WDT] Watchdog
  1088. See Documentation/watchdog/watchdog.txt.
  1089. xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks.
  1090. xd_geo= See header of drivers/block/xd.c.
  1091. xirc2ps_cs= [NET,PCMCIA]
  1092. Format: <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
  1093. Changelog:
  1094. The last known update (for 2.4.0) - the changelog was not kept before.
  1095. 2000-06-?? Mr. Unknown
  1096. Update for 2.5.49, description for most of the options introduced,
  1097. references to other documentation (C files, READMEs, ..), added S390,
  1098. PPC, SPARC, MTD, ALSA and OSS category. Minor corrections and
  1099. reformatting.
  1100. 2002-11-24 Petr Baudis <pasky@ucw.cz>
  1101. Randy Dunlap <randy.dunlap@verizon.net>
  1102. TODO:
  1103. Add documentation for ALSA options.
  1104. Add more DRM drivers.