1 February 2003 Kernel Parameters v2.5.59
4 The following is a consolidated list of the kernel parameters as implemented
5 (mostly) by the __setup() macro and sorted into English Dictionary order
6 (defined as ignoring all punctuation and sorting digits before letters in a
7 case insensitive manner), and with descriptions where known.
9 Module parameters for loadable modules are specified only as the
10 parameter name with optional '=' and value as appropriate, such as:
12 modprobe usbcore blinkenlights=1
14 Module parameters for modules that are built into the kernel image
15 are specified on the kernel command line with the module name plus
16 '.' plus parameter name, with '=' and value if appropriate, such as:
18 usbcore.blinkenlights=1
20 The text in square brackets at the beginning of the description state the
21 restrictions on the kernel for the said kernel parameter to be valid. The
22 restrictions referred to are that the relevant option is valid if:
24 ACPI ACPI support is enabled.
25 ALSA ALSA sound support is enabled.
26 APIC APIC support is enabled.
27 APM Advanced Power Management support is enabled.
28 AX25 Appropriate AX.25 support is enabled.
29 CD Appropriate CD support is enabled.
30 DEVFS devfs support is enabled.
31 DRM Direct Rendering Management support is enabled.
32 EFI EFI Partitioning (GPT) is enabled
33 EIDE EIDE/ATAPI support is enabled.
34 FB The frame buffer device is enabled.
35 HW Appropriate hardware is enabled.
36 IA-32 IA-32 aka i386 architecture is enabled.
37 IA-64 IA-64 architecture is enabled.
38 IOSCHED More than one I/O scheduler is enabled.
39 IP_PNP IP DCHP, BOOTP, or RARP is enabled.
40 ISAPNP ISA PnP code is enabled.
41 ISDN Appropriate ISDN support is enabled.
42 JOY Appropriate joystick support is enabled.
43 LP Printer support is enabled.
44 LOOP Loopback device support is enabled.
45 M68k M68k architecture is enabled.
46 These options have more detailed description inside of
47 Documentation/m68k/kernel-options.txt.
48 MCA MCA bus support is enabled.
49 MDA MDA console support is enabled.
50 MOUSE Appropriate mouse support is enabled.
51 MTD MTD support is enabled.
52 NET Appropriate network support is enabled.
53 NFS Appropriate NFS support is enabled.
54 OSS OSS sound support is enabled.
55 PARIDE The ParIDE subsystem is enabled.
56 PCI PCI bus support is enabled.
57 PCMCIA The PCMCIA subsystem is enabled.
58 PNP Plug & Play support is enabled.
59 PPC PowerPC architecture is enabled.
60 PPT Parallel port support is enabled.
61 PS2 Appropriate PS/2 support is enabled.
62 RAM RAM disk support is enabled.
63 S390 S390 architecture is enabled.
64 SCSI Appropriate SCSI support is enabled.
65 A lot of drivers has their options described inside of
67 SERIAL Serial support is enabled.
68 SMP The kernel is an SMP kernel.
69 SPARC Sparc architecture is enabled.
70 SWSUSP Software suspension is enabled.
71 TS Appropriate touchscreen support is enabled.
72 USB USB support is enabled.
73 V4L Video For Linux support is enabled.
74 VGA The VGA console has been enabled.
75 VT Virtual terminal support is enabled.
76 WDT Watchdog support is enabled.
77 XT IBM PC/XT MFM hard disk support is enabled.
79 In addition, the following text indicates that the option:
81 BUGS= Relates to possible processor bugs on the said processor.
82 KNL Is a kernel start-up parameter.
83 BOOT Is a boot loader parameter.
85 Parameters denoted with BOOT are actually interpreted by the boot
86 loader, and have no meaning to the kernel directly.
87 Do not modify the syntax of boot loader parameters without extreme
88 need or coordination with <Documentation/i386/boot.txt>.
90 Note that ALL kernel parameters listed below are CASE SENSITIVE, and that
91 a trailing = on the name of any parameter states that that parameter will
92 be entered as an environment variable, whereas its absence indicates that
93 it will appear as a kernel argument readable via /proc/cmdline by programs
94 running once the system is up.
96 53c7xx= [HW,SCSI] Amiga SCSI controllers
97 See header of drivers/scsi/53c7xx.c.
98 See also Documentation/scsi/ncr53c7xx.txt.
100 98busmouse.irq= [HW,MOUSE] PC-9801 Bus Mouse Driver
101 Format: <irq>, default is 13
103 acpi= [HW,ACPI] Advanced Configuration and Power Interface
104 Format: { force | off | ht | strict }
105 force -- enable ACPI if default was off
106 off -- disable ACPI if default was on
107 noirq -- do not use ACPI for IRQ routing
108 ht -- run only enough ACPI to enable Hyper Threading
109 strict -- Be less tolerant of platforms that are not
110 strictly ACPI specification compliant.
112 See also Documentation/pm.txt, pci=noacpi
114 acpi_sleep= [HW,ACPI] Sleep options
115 Format: { s3_bios, s3_mode }
116 See Documentation/power/video.txt
118 acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
119 Format: { level | edge | high | low }
121 acpi_irq_balance [HW,ACPI] ACPI will balance active IRQs
124 acpi_irq_nobalance [HW,ACPI] ACPI will not move active IRQs (default)
127 acpi_irq_pci= [HW,ACPI] If irq_balance, Clear listed IRQs for use by PCI
128 Format: <irq>,<irq>...
130 acpi_irq_isa= [HW,ACPI] If irq_balance, Mark listed IRQs used by ISA
131 Format: <irq>,<irq>...
133 acpi_osi= [HW,ACPI] empty param disables _OSI
135 acpi_serialize [HW,ACPI] force serialization of AML methods
137 acpi_skip_timer_override [HW,ACPI]
138 Recognize and ignore IRQ0/pin2 Interrupt Override.
139 For broken nForce2 BIOS resulting in XT-PIC timer.
142 Format: <io>,<irq>,<dma>,<dma2>
143 See also Documentation/sound/oss/AD1816.
146 Format: <io>,<irq>,<dma>,<dma2>,<type>
152 See header of drivers/scsi/advansys.c.
154 advwdt= [HW,WDT] Advantech WDT
155 Format: <iostart>,<iostop>
157 aedsp16= [HW,OSS] Audio Excel DSP 16
158 Format: <io>,<irq>,<dma>,<mss_io>,<mpu_io>,<mpu_irq>
159 See also header of sound/oss/aedsp16.c.
162 See Documentation/scsi/aha152x.txt.
165 Format: <portbase>[,<buson>,<busoff>[,<dmaspeed>]]
168 See Documentation/scsi/aic7xxx.txt.
171 See Documentation/scsi/aic79xx.txt.
176 Format: <host-scsi-id>,<target-scsi-id>,<max-rate>,<max-offset>
177 See also header of drivers/scsi/AM53C974.c.
179 amijoy.map= [HW,JOY] Amiga joystick support
180 Map of devices attached to JOY0DAT and JOY1DAT
182 See also Documentation/kernel/input/joystick.txt
184 analog.map= [HW,JOY] Analog joystick and gamepad support
185 Specifies type or capabilities of an analog joystick
186 connected to one of 16 gameports
187 Format: <type1>,<type2>,..<type16>
189 apc= [HW,SPARC] Power management functions (SPARCstation-4/5 + deriv.)
191 Disable APC CPU standby support. SPARCstation-Fox does
192 not play well with APC CPU idle - disable it if you have
193 APC and your system crashes randomly.
195 apm= [APM] Advanced Power Management
196 See header of arch/i386/kernel/apm.c.
201 arcrimi= [HW,NET] ARCnet - "RIM I" (entirely mem-mapped) cards
202 Format: <io>,<irq>,<nodeID>
206 atarimouse= [HW,MOUSE] Atari Mouse
208 atascsi= [HW,SCSI] Atari SCSI
210 atkbd.extra= [HW] Enable extra LEDs and keys on IBM RapidAccess, EzKey
211 and similar keyboards
213 atkbd.reset= [HW] Reset keyboard during initialization
215 atkbd.set= [HW] Select keyboard code set
216 Format: <int> (2 = AT (default) 3 = PS/2)
218 atkbd.scroll= [HW] Enable scroll wheel on MS Office and similar keyboards
221 [HW] Use software keyboard repeat
225 awe= [HW,OSS] AWE32/SB32/AWE64 wave table synth
226 Format: <io>,<memsize>,<isapnp>
228 aztcd= [HW,CD] Aztech CD268 CDROM driver
229 Format: <io>,0x79 (?)
231 baycom_epp= [HW,AX25]
234 baycom_par= [HW,AX25] BayCom Parallel Port AX.25 Modem
236 See header of drivers/net/hamradio/baycom_par.c.
238 baycom_ser_fdx= [HW,AX25] BayCom Serial Port AX.25 Modem (Full Duplex Mode)
239 Format: <io>,<irq>,<mode>[,<baud>]
240 See header of drivers/net/hamradio/baycom_ser_fdx.c.
242 baycom_ser_hdx= [HW,AX25] BayCom Serial Port AX.25 Modem (Half Duplex Mode)
243 Format: <io>,<irq>,<mode>
244 See header of drivers/net/hamradio/baycom_ser_hdx.c.
246 blkmtd_device= [HW,MTD]
252 bttv.card= [HW,V4L] bttv (bt848 + bt878 based grabber cards)
253 bttv.radio= Most important insmod options are available as kernel args too.
254 bttv.pll= See Documentation/video4linux/bttv/Insmod-options
255 bttv.tuner= and Documentation/video4linux/bttv/CARDLIST
258 See drivers/scsi/BusLogic.c, comment before function
259 BusLogic_ParseDriverOptions().
261 c101= [NET] Moxa C101 synchronous serial card
263 cachesize= [BUGS=IA-32] Override level 2 CPU cache size detection.
264 Sometimes CPU hardware bugs make them report the cache
265 size incorrectly. The kernel will attempt work arounds
266 to fix known problems, but for some CPUs it is not
267 possible to determine what the correct size should be.
268 This option provides an override for these situations.
271 Format: <io>,<irq>[,PAS]
272 See header of drivers/cdrom/cdu31a.c.
274 chandev= [HW,NET] Generic channel device initialisation
276 clock= [BUGS=IA-32, HW] gettimeofday timesource override.
277 Forces specified timesource (if avaliable) to be used
278 when calculating gettimeofday(). If specicified timesource
279 is not avalible, it defaults to PIT.
280 Format: { pit | tsc | cyclone | pmtmr }
282 hpet= [IA-32,HPET] option to disable HPET and use PIT.
286 Format: { auto | [<io>,][<irq>] }
288 com20020= [HW,NET] ARCnet - COM20020 chipset
289 Format: <io>[,<irq>[,<nodeID>[,<backplane>[,<ckp>[,<timeout>]]]]]
291 com90io= [HW,NET] ARCnet - COM90xx chipset (IO-mapped buffers)
294 com90xx= [HW,NET] ARCnet - COM90xx chipset (memory-mapped buffers)
295 Format: <io>[,<irq>[,<memstart>]]
297 condev= [HW,S390] console device
300 console= [KNL] Output console
301 Console device and comm spec (speed, control, parity).
303 cpcihp_generic= [HW,PCI] Generic port I/O CompactPCI driver
304 Format: <first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
307 Format: { parport<nr> | auto | none }
310 Format: <io>,<irq>,<dma>,<dma2>,<mpuio>,<mpuirq>
315 cs89x0_media= [HW,NET]
316 Format: { rj45 | aui | bnc }
318 cyclades= [HW,SERIAL] Cyclades multi-serial port adapter.
321 See header of drivers/s390/block/dasd_devmap.c.
323 db9.dev[2|3]= [HW,JOY] Multisystem joystick support via parallel port
324 (one device per port)
325 Format: <port#>,<type>
326 See also Documentation/input/joystick-parport.txt
328 debug [KNL] Enable kernel debugging (events log level).
331 Format: <area>[,<node>]
332 See also Documentation/networking/decnet.txt.
335 See Documentation/filesystems/devfs/boot-options.
338 Set number of hash buckets for dentry cache.
341 IO parameters + enable/disable command.
343 digiepca= [HW,SERIAL]
344 See drivers/char/README.epca and
345 Documentation/digiepca.txt.
347 dmascc= [HW,AX25,SERIAL] AX.25 Z80SCC driver with DMA
349 Format: <io_dev0>[,<io_dev1>[,..<io_dev32>]]
351 dmasound= [HW,OSS] Sound subsystem buffers
357 earlyprintk= [x86, x86_64]
359 earlyprintk=serial[,ttySn[,baudrate]]
361 Append ,keep to not disable it when the real console
364 Only vga or serial at a time, not both.
366 Currently only ttyS0 and ttyS1 are supported.
368 Interaction with the standard serial driver is not
371 The VGA output is eventually overwritten by the real
381 Format: <id>,<membase>,<irq>
383 eisa_irq_edge= [PARISC]
384 See header of drivers/parisc/eisa.c.
387 See comment before function elanfreq_setup() in
388 arch/i386/kernel/cpu/cpufreq/elanfreq.c.
391 Format: {"as"|"cfq"|"deadline"|"noop"}
392 See Documentation/as-iosched.txt for details
395 Format: <lineout>[,<micbias>]
396 See also header of sound/oss/es1370.c.
399 Format: <spdif>,[<nomix>,[<amplifier>]]
400 See also header of sound/oss/es1371.c.
402 ether= [HW,NET] Ethernet cards parameters
403 This option is obsoleted by the "netdev=" option, which
404 has equivalent usage. See its documentation for details.
406 eurwdt= [HW,WDT] Eurotech CPU-1220/1410 onboard watchdog.
410 See header of drivers/scsi/fd_mcs.c.
413 See header of drivers/scsi/fdomain.c.
416 See Documentation/floppy.txt.
418 ftape= [HW] Floppy Tape subsystem debugging options.
419 See Documentation/ftape.txt.
422 [HW,JOY] Multisystem joystick and NES/SNES/PSX pad
423 support via parallel port (up to 5 devices per port)
424 Format: <port#>,<pad1>,<pad2>,<pad3>,<pad4>,<pad5>
425 See also Documentation/input/joystick-parport.txt
430 See header of drivers/scsi/gdth.c.
432 gpt [EFI] Forces disk with valid GPT signature but
433 invalid Protective MBR to be treated as GPT.
438 gt96100eth= [NET] MIPS GT96100 Advanced Communication Controller
441 Format: <io>,<irq>,<dma>,<dma16>
445 hcl= [IA-64] SGI's Hardware Graph compatibility layer
447 hd= [EIDE] (E)IDE hard drive subsystem geometry
448 Format: <cyl>,<head>,<sect>
450 hd?= [HW] (E)IDE subsystem
451 hd?lun= See Documentation/ide.txt.
454 See Documentation/isdn/README.HiSax.
456 hugepages= [HW,IA-32,IA-64] Maximal number of HugeTLB pages.
458 noirqbalance [IA-32,SMP,KNL] Disable kernel irq balancing
460 i8042.direct [HW] Put keyboard port into non-translated mode
461 i8042.dumbkbd [HW] Pretend that controlled can only read data from
462 keyboard and can not control its state
463 (Don't attempt to blink the leds)
464 i8042.noaux [HW] Don't check for auxiliary (== mouse) port
465 i8042.nomux [HW] Don't check presence of an active multiplexing
467 i8042.reset [HW] Reset the controller during init and cleanup
468 i8042.unlock [HW] Unlock (ignore) the keylock
472 ibmmcascsi= [HW,MCA,SCSI] IBM MicroChannel SCSI adapter
473 See Documentation/mca.txt.
476 Format: <io>[,<membase>[,<icn_id>[,<icn_id2>]]]
478 ide?= [HW] (E)IDE subsystem
479 Config (iomem/irq), tuning or debugging
480 (serialize,reset,no{dma,tune,probe}) or chipset
482 See Documentation/ide.txt.
484 idebus= [HW] (E)IDE subsystem - VLB/PCI bus speed
485 See Documentation/ide.txt.
488 Format: idle=poll or idle=halt
491 Set number of hash buckets for inode cache.
494 See header of drivers/scsi/in2000.c.
498 Run specified binary instead of /sbin/init as init
501 initcall_debug [KNL] Trace initcalls as they are executed. Useful
502 for working out where the kernel is dying during
505 initrd= [BOOT] Specify the location of the initial ramdisk
507 inport.irq= [HW] Inport (ATI XL and Microsoft) busmouse driver
512 io7= [HW] IO7 for Marvel based alpha systems
513 See comment before marvel_specify_io7 in
514 arch/alpha/kernel/core_marvel.c.
517 See Documentation/nfsroot.txt.
519 ip2= [HW] Set IO/IRQ pairs for up to 4 IntelliPort boards
520 See comment before ip2_setup() in drivers/char/ip2.c.
522 ips= [HW,SCSI] Adaptec / IBM ServeRAID controller
523 See header of drivers/scsi/ips.c.
526 Format: <RDP>, <reset>, <pci_scan>, <verbosity>
529 Format: <io>,<irq>,<dma>,<setup>
533 js= [HW,JOY] Analog joystick
534 See Documentation/input/joystick.txt.
540 lapic [IA-32,APIC] Enable the local APIC even if BIOS disabled it.
542 lasi= [HW,SCSI] PARISC LASI driver for the 53c700 chip
543 Format: addr:<io>,irq:<irq>
546 See function print_params() in arch/ia64/sn/kernel/llsc4.c.
548 load_ramdisk= [RAM] List of ramdisks to load from floppy
549 See Documentation/ramdisk.txt.
555 logibm.irq= [HW,MOUSE] Logitech Bus Mouse Driver
558 log_buf_len=n Sets the size of the printk ring buffer, in bytes.
559 Format is n, nk, nM. n must be a power of two. The
560 default is set in kernel config.
562 lp=0 [LP] Specify parallel ports to use, e.g,
563 lp=port[,port...] lp=none,parport0 (lp0 not configured, lp1 uses
564 lp=reset first parallel port). 'lp=0' disables the
565 lp=auto printer driver. 'lp=reset' (which can be
566 specified in addition to the ports) causes
567 attached printers to be reset. Using
568 lp=port1,port2,... specifies the parallel ports
569 to associate lp devices with, starting with
570 lp0. A port specification may be 'none' to skip
571 that lp device, or a parport name such as
572 'parport0'. Specifying 'lp=auto' instead of a
573 port specification list means that device IDs
574 from each port should be examined, to see if
575 an IEEE 1284-compliant printer is attached; if
576 so, the driver will manage that printer.
577 See also header of drivers/char/lp.c.
580 Format: <io>,<irq>,<dma>
583 Format: <can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
586 Format: <num_esps>,<disconnect>,<nosync>,<can_queue>,<cmd_per_lun>,<sg_tablesize>,<hostid>,<use_tags>
589 Format: <io>,<irq>,<dma>,<dma16>,<mpu_io>,<mpu_irq>,<joystick>
594 max_loop= [LOOP] Maximum number of loopback devices that can
598 maxcpus= [SMP] Maximum number of processors that an SMP kernel
601 max_scsi_luns= [SCSI]
603 max_scsi_report_luns=
604 [SCSI] Maximum number of LUNs received
605 Should be between 1 and 16384.
607 mca-pentium [BUGS=IA-32]
612 Format: <port>,<irq>,<mitsumi_bug_93_wait>
616 mce [IA-32] Machine Check Exception
618 md= [HW] RAID subsystems devices and level
619 See Documentation/md.txt.
622 Format: <first>,<last>
623 Specifies range of consoles to be captured by the MDA.
625 mem=nn[KMG] [KNL,BOOT] Force usage of a specific amount of memory
626 Amount of memory to be used when the kernel is not able
627 to see the whole system memory or for test.
629 mem=nopentium [BUGS=IA-32] Disable usage of 4MB pages for kernel
632 memmap=exactmap [KNL,IA-32] Enable setting of an exact
633 E820 memory map, as specified by the user.
634 Such memmap=exactmap lines can be constructed based on
635 BIOS output or other requirements. See the memmap=nn@ss
638 memmap=nn[KMG]@ss[KMG]
639 [KNL] Force usage of a specific region of memory
640 Region of memory to be used, from ss to ss+nn.
642 memmap=nn[KMG]#ss[KMG]
643 [KNL,ACPI] Mark specific memory as ACPI data.
644 Region of memory to be used, from ss to ss+nn.
646 memmap=nn[KMG]$ss[KMG]
647 [KNL,ACPI] Mark specific memory as reserved.
648 Region of memory to be used, from ss to ss+nn.
650 meye= [HW] Set MotionEye Camera parameters
651 See Documentation/video4linux/meye.txt.
655 mousedev.xres= [MOUSE] Horizontal screen resolution, used for devices
656 reporting absolute coordinates, such as tablets
657 mousedev.yres= [MOUSE] Vertical screen resolution, used for devices
658 reporting absolute coordinates, such as tablets
664 Format: <name>,<region-number>,<size>,<offset>
667 Format: <name>,<region-number>[,<base>,<size>,<buswidth>,<altbuswidth>]
670 See drivers/mtd/cmdline.c.
672 n2= [NET] SDL Inc. RISCom/N2 synchronous serial card
675 See header of drivers/scsi/NCR_D700.c.
681 ncr53c400a= [HW,SCSI]
683 ncr53c406a= [HW,SCSI]
687 netdev= [NET] Network devices parameters
688 Format: <irq>,<io>,<mem_start>,<mem_end>,<name>
689 Note that mem_start is often overloaded to mean
690 something different and driver-specific.
693 See Documentation/nfsroot.txt.
695 nfsroot= [NFS] nfs root filesystem for disk-less boxes.
696 See Documentation/nfsroot.txt.
698 nmi_watchdog= [KNL,BUGS=IA-32] Debugging features for SMP kernels
700 no387 [BUGS=IA-32] Tells the kernel to use the 387 maths
701 emulation library even if a 387 maths coprocessor
706 noapic [SMP,APIC] Tells the kernel not to make use of any
707 APIC that may be present on the system.
709 noasync [HW,M68K] Disables async and sync negotiation for
714 nodisconnect [HW,SCSI,M68K] Disables SCSI disconnects.
720 nohighio [BUGS=IA-32] Disable highmem block I/O.
724 no-hlt [BUGS=IA-32] Tells the kernel that the hlt
725 instruction doesn't work correctly and not to
728 noirqdebug [IA-32] Disables the code which attempts to detect and
729 disable unhandled interrupt sources.
731 noisapnp [ISAPNP] Disables ISA PnP code.
733 noinitrd [RAM] Tells the kernel not to load any configured
738 nolapic [IA-32,APIC] Do not enable or use the local APIC.
740 nomce [IA-32] Machine Check Exception
742 noresume [SWSUSP] Disables resume and restore original swap space.
744 no-scroll [VGA] Disables scrollback.
745 This is required for the Braillex ib80-piezo Braille
746 reader made by F.H. Papenmeier (Germany).
750 nosmp [SMP] Tells an SMP kernel to act as a UP kernel.
752 nosync [HW,M68K] Disables sync negotiation for all devices.
754 notsc [BUGS=IA-32] Disable Time Stamp Counter
756 nousb [USB] Disable the USB subsystem
764 Format: <io>,<irq>,<dma>,<dma2>,<mpu_io>,<mpu_irq>
767 Format: <io>,<irq>,<dma>,<dma2>,<mss_io>,<mpu_io>,<ymode>,<loopback>[,<isapnp>,<multiple]
770 Use timer interrupt instead of performance counters
775 osst= [HW,SCSI] SCSI Tape Driver
776 Format: <buffer_size>,<write_threshold>
777 See also Documentation/scsi/st.txt.
779 panic= [KNL] Kernel behaviour on panic
782 parport=0 [HW,PPT] Specify parallel ports. 0 disables.
783 parport=auto Use 'auto' to force the driver to use
784 parport=0xBBB[,IRQ[,DMA]] any IRQ/DMA settings detected (the
785 default is to ignore detected IRQ/DMA
786 settings because of possible
787 conflicts). You can specify the base
788 address, IRQ, and DMA settings; IRQ and
789 DMA should be numbers, or 'auto' (for
790 using detected settings on that
791 particular port), or 'nofifo' (to avoid
792 using a FIFO even if it is detected).
793 Parallel ports are assigned in the
794 order they are specified on the command
795 line, starting with parport0.
798 Format: <io>,<irq>,<dma>,<dma16>,<sb_io>,<sb_irq>,<sb_dma>,<sb_dma16>
801 See header of drivers/scsi/pas16.c.
806 See header of drivers/block/paride/pcd.c.
807 See also Documentation/paride.txt.
809 pci=option[,option...] [PCI] various PCI subsystem options:
810 off [IA-32] don't probe for the PCI bus
811 bios [IA-32] force use of PCI BIOS, don't access
812 the hardware directly. Use this if your machine
813 has a non-standard PCI host bridge.
814 nobios [IA-32] disallow use of PCI BIOS, only direct
815 hardware access methods are allowed. Use this
816 if you experience crashes upon bootup and you
817 suspect they are caused by the BIOS.
818 conf1 [IA-32] Force use of PCI Configuration Mechanism 1.
819 conf2 [IA-32] Force use of PCI Configuration Mechanism 2.
820 nosort [IA-32] Don't sort PCI devices according to
821 order given by the PCI BIOS. This sorting is done
822 to get a device order compatible with older kernels.
823 biosirq [IA-32] Use PCI BIOS calls to get the interrupt
824 routing table. These calls are known to be buggy
825 on several machines and they hang the machine when used,
826 but on other computers it's the only way to get the
827 interrupt routing table. Try this option if the kernel
828 is unable to allocate IRQs or discover secondary PCI
829 buses on your motherboard.
830 rom [IA-32] Assign address space to expansion ROMs.
831 Use with caution as certain devices share address
832 decoders between ROMs and other resources.
833 irqmask=0xMMMM [IA-32] Set a bit mask of IRQs allowed to be assigned
834 automatically to PCI devices. You can make the kernel
835 exclude IRQs of your ISA cards this way.
836 lastbus=N [IA-32] Scan all buses till bus #N. Can be useful
837 if the kernel is unable to find your secondary buses
838 and you want to tell it explicitly which ones they are.
839 assign-busses [IA-32] Always assign all PCI bus
840 numbers ourselves, overriding
841 whatever the firmware may have
843 usepirqmask [IA-32] Honor the possible IRQ mask
844 stored in the BIOS $PIR table. This is
845 needed on some systems with broken
846 BIOSes, notably some HP Pavilion N5400
847 and Omnibook XE3 notebooks. This will
848 have no effect if ACPI IRQ routing is
850 noacpi [IA-32] Do not use ACPI for IRQ routing
853 pcmv= [HW,PCMCIA] BadgePAD 4
856 See Documentation/paride.txt.
859 See Documentation/paride.txt.
862 See Documentation/paride.txt.
864 pirq= [SMP,APIC] Manual mp-table setup
865 See Documentation/i386/IO-APIC.txt.
867 plip= [PPT,NET] Parallel port network link
868 Format: { parport<nr> | timid | 0 }
869 See also Documentation/parport.txt.
872 { on | off | curr | res | no-curr | no-res }
875 [ISAPNP] Exclude IRQs for the autoconfiguration
878 [ISAPNP] Exclude DMAs for the autoconfiguration
880 pnp_reserve_io= [ISAPNP] Exclude I/O ports for the autoconfiguration
881 Ranges are in pairs (I/O port base and size).
884 [ISAPNP] Exclude memory regions for the autoconfiguration
885 Ranges are in pairs (memory base and size).
887 profile= [KNL] Enable kernel profiling via /proc/profile
888 (param: profile step/bucket size as a power of 2)
890 prompt_ramdisk= [RAM] List of RAM disks to prompt for floppy disk
892 See Documentation/ramdisk.txt.
894 psmouse.proto= [HW,MOUSE] Highest PS2 mouse protocol extension to
895 probe for (bare|imps|exps).
896 psmouse.rate= [HW,MOUSE] Set desired mouse report rate, in reports
899 [HW,MOUSE] Try to reset Synaptics Touchpad after so many
900 bad packets (0 = never).
902 [HW,MOUSE] Set desired mouse resolution, in dpi.
904 [HW,MOUSE] Controls Logitech smartscroll autorepeat,
905 0 = disabled, 1 = enabled (default).
907 pss= [HW,OSS] Personal Sound System (ECHO ESC614)
908 Format: <io>,<mss_io>,<mss_irq>,<mss_dma>,<mpu_io>,<mpu_irq>
911 See Documentation/paride.txt.
913 quiet= [KNL] Disable log messages
918 See Documentation/md.txt.
920 ramdisk= [RAM] Sizes of RAM disks in kilobytes [deprecated]
921 See Documentation/ramdisk.txt.
925 See Documentation/ramdisk.txt.
927 ramdisk_size= [RAM] Sizes of RAM disks in kilobytes
928 New name for the ramdisk parameter.
929 See Documentation/ramdisk.txt.
931 ramdisk_start= [RAM] Starting block of RAM disk image (so you can
932 place it after the kernel image on a boot floppy).
933 See Documentation/ramdisk.txt.
935 reboot= [BUGS=IA-32,BUGS=ARM,BUGS=IA-64] Rebooting mode
936 Format: <reboot_mode>[,<reboot_mode2>[,...]]
937 See arch/*/kernel/reboot.c.
939 reserve= [KNL,BUGS] Force the kernel to ignore some iomem area
941 resume= [SWSUSP] Specify the partition device for software suspension
943 rhash_entries= [KNL,NET]
944 Set number of hash buckets for route cache
947 Format: <io_board1>[,<io_board2>[,...<io_boardN>]]
949 ro [KNL] Mount root device read-only on boot
951 root= [KNL] Root filesystem
953 rootflags= [KNL] Set root filesystem mount option string
955 rootfstype= [KNL] Set root filesystem type
957 rw [KNL] Mount root device read-write on boot
959 S [KNL] Run init in single mode
962 See drivers/net/irda/sa1100_ir.c.
965 Format: <io>,<irq>,<dma>,<dma2>
967 sbni= [NET] Granch SBNI12 leased line adapter
969 sbpcd= [HW,CD] Soundblaster CD adapter
971 See a comment before function sbpcd_setup() in
972 drivers/cdrom/sbpcd.c.
974 sc1200wdt= [HW,WDT] SC1200 WDT (watchdog) driver
975 Format: <io>[,<timeout>[,<isapnp>]]
978 See drivers/scsi/scsi_debug.c.
980 scsi_default_dev_flags=
981 [SCSI] SCSI default device flags
984 scsi_dev_flags= [SCSI] Black/white list entry for vendor and model
985 Format: <vendor>:<model>:<flags>
986 (flags are integer value)
992 serialnumber [BUGS=IA-32]
994 sf16fm= [HW] SF16FMI radio driver for Linux
997 sg_def_reserved_size=
1001 Format: <io>,<irq>,<dma>,<dma2>,<sgbase>
1004 Maximal number of shapers.
1007 See header of drivers/scsi/sim710.c.
1013 Format: <io>,<irq>,<dma>
1014 See header of drivers/cdrom/sjcd.c.
1019 Format: <io1>[,<io2>[,...,<io8>]]
1021 snd-ad1816a= [HW,ALSA]
1023 snd-ad1848= [HW,ALSA]
1025 snd-ali5451= [HW,ALSA]
1027 snd-als100= [HW,ALSA]
1029 snd-als4000= [HW,ALSA]
1031 snd-azt2320= [HW,ALSA]
1033 snd-cmi8330= [HW,ALSA]
1035 snd-cmipci= [HW,ALSA]
1037 snd-cs4231= [HW,ALSA]
1039 snd-cs4232= [HW,ALSA]
1041 snd-cs4236= [HW,ALSA]
1043 snd-cs4281= [HW,ALSA]
1045 snd-cs46xx= [HW,ALSA]
1047 snd-dt019x= [HW,ALSA]
1049 snd-dummy= [HW,ALSA]
1051 snd-emu10k1= [HW,ALSA]
1053 snd-ens1370= [HW,ALSA]
1055 snd-ens1371= [HW,ALSA]
1057 snd-es968= [HW,ALSA]
1059 snd-es1688= [HW,ALSA]
1061 snd-es18xx= [HW,ALSA]
1063 snd-es1938= [HW,ALSA]
1065 snd-es1968= [HW,ALSA]
1067 snd-fm801= [HW,ALSA]
1069 snd-gusclassic= [HW,ALSA]
1071 snd-gusextreme= [HW,ALSA]
1073 snd-gusmax= [HW,ALSA]
1077 snd-ice1712= [HW,ALSA]
1079 snd-intel8x0= [HW,ALSA]
1081 snd-interwave= [HW,ALSA]
1086 snd-korg1212= [HW,ALSA]
1088 snd-maestro3= [HW,ALSA]
1090 snd-mpu401= [HW,ALSA]
1092 snd-mtpav= [HW,ALSA]
1094 snd-nm256= [HW,ALSA]
1096 snd-opl3sa2= [HW,ALSA]
1104 snd-opti93x= [HW,ALSA]
1108 snd-rme32= [HW,ALSA]
1110 snd-rme96= [HW,ALSA]
1112 snd-rme9652= [HW,ALSA]
1118 snd-sbawe= [HW,ALSA]
1120 snd-serial= [HW,ALSA]
1122 snd-sgalaxy= [HW,ALSA]
1124 snd-sonicvibes= [HW,ALSA]
1129 snd-sun-cs4231= [HW,ALSA]
1131 snd-trident= [HW,ALSA]
1133 snd-usb-audio= [HW,ALSA,USB]
1135 snd-via82xx= [HW,ALSA]
1137 snd-virmidi= [HW,ALSA]
1139 snd-wavefront= [HW,ALSA]
1141 snd-ymfpci= [HW,ALSA]
1143 sonicvibes= [HW,OSS]
1147 Format: <io>[,<irq>]
1149 sonypi= [HW] Sony Programmable I/O Control Device driver
1150 Format: <minor>,<verbose>,<fnkeyinit>,<camera>,<compat>,<nojogdial>
1152 specialix= [HW,SERIAL] Specialix multi-serial port adapter
1153 See Documentation/specialix.txt.
1155 speedstep_coppermine=
1156 [HW,IA-32] Take CPU in your notebook as SpeedStep-capable
1157 See comment before function speedstep_setup() in
1158 arch/i386/kernel/cpu/cpufreq/speedstep.c.
1160 spia_io_base= [HW,MTD]
1166 Format: <io>,<irq>,<dma>,<mpu_io>,<mpu_irq>
1168 st= [HW,SCSI] SCSI tape parameters (buffers, etc.)
1169 See Documentation/scsi/st.txt.
1172 See header of drivers/scsi/seagate.c.
1176 Set the STI (builtin display/keyboard on the HP-PARISC
1177 machines) console (graphic card) which should be used
1178 as the initial boot-console.
1179 See also comment in drivers/video/console/sticore.c.
1182 See comment in drivers/video/console/sticore.c.
1185 Format: bpp:<bpp1>[:<bpp2>[:<bpp3>...]]
1187 stram_swap= [HW,M68k]
1189 swiotlb= [IA-64] Number of I/O TLB slabs
1193 sym53c416= [HW,SCSI]
1194 See header of drivers/scsi/sym53c416.c.
1196 sym53c8xx= [HW,SCSI]
1197 See Documentation/scsi/ncr53c8xx.txt.
1200 See header of drivers/scsi/t128.c.
1204 thash_entries= [KNL,NET]
1205 Set number of hash buckets for TCP connection
1208 See header of drivers/char/tipar.c.
1210 tiusb= [HW,USB] Texas Instruments' USB GraphLink (aka SilverLink)
1214 See header of drivers/scsi/seagate.c.
1217 See comment before function dc390_setup() in
1218 drivers/scsi/tmscsim.c.
1222 trix= [HW,OSS] MediaTrix AudioTrix Pro
1223 Format: <io>,<irq>,<dma>,<dma2>,<sb_io>,<sb_irq>,<sb_dma>,<mpu_io>,<mpu_irq>
1225 tsdev.xres= [TS] Horizontal screen resolution.
1226 tsdev.yres= [TS] Vertical screen resolution.
1228 turbografx.map[2|3]=
1229 [HW,JOY] TurboGraFX parallel port interface
1230 Format: <port#>,<js1>,<js2>,<js3>,<js4>,<js5>,<js6>,<js7>
1231 See also Documentation/input/joystick-parport.txt
1233 u14-34f= [HW,SCSI] UltraStor 14F/34F SCSI host adapter
1234 See header of drivers/scsi/u14-34f.c.
1242 video= [FB] Frame buffer configuration
1243 See Documentation/fb/modedb.txt.
1245 vga= [BOOT,IA-32] Select a particular video mode
1246 See Documentation/i386/boot.txt and Documentation/svga.txt.
1247 Use vga=ask for menu.
1248 This is actually a boot loader parameter; the value is
1249 passed to the kernel using a special protocol.
1255 waveartist= [HW,OSS]
1256 Format: <io>,<irq>,<dma>,<dma2>
1259 See header of drivers/scsi/wd33c93.c.
1262 See header of drivers/scsi/wd7000.c.
1265 See Documentation/watchdog/watchdog.txt.
1267 xd= [HW,XT] Original XT pre-IDE (RLL encoded) disks.
1268 xd_geo= See header of drivers/block/xd.c.
1270 xirc2ps_cs= [NET,PCMCIA]
1271 Format: <irq>,<irq_mask>,<io>,<full_duplex>,<do_sound>,<lockup_hack>[,<irq2>[,<irq3>[,<irq4>]]]
1277 The last known update (for 2.4.0) - the changelog was not kept before.
1278 2000-06-?? Mr. Unknown
1280 Update for 2.5.49, description for most of the options introduced,
1281 references to other documentation (C files, READMEs, ..), added S390,
1282 PPC, SPARC, MTD, ALSA and OSS category. Minor corrections and
1284 2002-11-24 Petr Baudis <pasky@ucw.cz>
1285 Randy Dunlap <randy.dunlap@verizon.net>
1289 Add documentation for ALSA options.
1290 Add more DRM drivers.