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diff --git a/man7/bootparam.7 b/man7/bootparam.7 new file mode 100644 index 000000000..e196ebb56 --- /dev/null +++ b/man7/bootparam.7 @@ -0,0 +1,1234 @@ +.\" Copyright (c) 1995,1997 Paul Gortmaker and Andries Brouwer +.\" +.\" This is free documentation; you can redistribute it and/or +.\" modify it under the terms of the GNU General Public License as +.\" published by the Free Software Foundation; either version 2 of +.\" the License, or (at your option) any later version. +.\" +.\" The GNU General Public License's references to "object code" +.\" and "executables" are to be interpreted as the output of any +.\" document formatting or typesetting system, including +.\" intermediate and printed output. +.\" +.\" This manual is distributed in the hope that it will be useful, +.\" but WITHOUT ANY WARRANTY; without even the implied warranty of +.\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +.\" GNU General Public License for more details. +.\" +.\" You should have received a copy of the GNU General Public +.\" License along with this manual; if not, write to the Free +.\" Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, +.\" USA. +.\" +.\" This man page written 950814 by aeb, based on Paul Gortmaker's HOWTO +.\" (dated v1.0.1, 15/08/95). +.\" Major update, aeb, 970114. +.\" +.TH BOOTPARAM 7 1995-01-14 "Linux 2.1.21" "Linux Programmer's Manual" +.SH NAME +bootparam \- Introduction to boot time parameters of the Linux kernel +.SH DESCRIPTION +The Linux kernel accepts certain `command line options' or `boot time +parameters' at the moment it is started. In general this is used to +supply the kernel with information about hardware parameters that +the kernel would not be able to determine on its own, or to avoid/override +the values that the kernel would otherwise detect. + +When the kernel is booted directly by the BIOS (say from a floppy to +which you copied a kernel using `cp zImage /dev/fd0'), +you have no opportunity to specify any parameters. +So, in order to take advantage of this possibility you have to +use software that is able to pass parameters, like LILO or loadlin. +For a few parameters one can also modify the kernel image itself, +using rdev, see +.BR rdev (8) +for further details. + +The LILO program (LInux LOader) written by Werner Almesberger is the +most commonly used. It has the ability to boot various kernels, and +stores the configuration information in a plain text file. (See +.BR lilo (8) +and +.BR lilo.conf (5).) +LILO can boot DOS, OS/2, Linux, FreeBSD, UnixWare, etc., and is quite flexible. + +The other commonly used Linux loader is `LoadLin' which is a DOS +program that has the capability to launch a Linux kernel from the DOS +prompt (with boot-args) assuming that certain resources are available. +This is good for people that want to launch Linux from DOS. + +It is also very useful if you have certain hardware which relies on +the supplied DOS driver to put the hardware into a known state. A +common example is `SoundBlaster Compatible' sound cards that require +the DOS driver to twiddle a few mystical registers to put the card +into a SB compatible mode. Booting DOS with the supplied driver, and +then loading Linux from the DOS prompt with loadlin avoids the reset +of the card that happens if one rebooted instead. + +.SH "THE ARGUMENT LIST" + +The kernel command line is parsed into a list of strings +(boot arguments) separated by spaces. Most of the boot args +take the form of: +.IP +name[=value_1][,value_2]...[,value_10] +.LP +where `name' is a unique keyword that is used to identify what part of +the kernel the associated values (if any) are to be given to. +Note the limit of 10 is real, as the present code only handles 10 comma +separated parameters per keyword. (However, you can re-use the same +keyword with up to an additional 10 parameters in unusually +complicated situations, assuming the setup function supports it.) + +Most of the sorting goes on in linux/init/main.c. First, the kernel +checks to see if the argument is any of the special arguments `root=', +`nfsroot=', `nfsaddrs=', `ro', `rw', `debug' or `init'. The meaning +of these special arguments is described below. + +Then it walks a list of setup functions (contained in the bootsetups +array) to see if the specified argument string (such as `foo') has +been associated with a setup function (`foo_setup()') for a particular +device or part of the kernel. If you passed the kernel the line +foo=3,4,5,6 then the kernel would search the bootsetups array to see +if `foo' was registered. If it was, then it would call the setup +function associated with `foo' (foo_setup()) and hand it the arguments +3, 4, 5 and 6 as given on the kernel command line. + +Anything of the form `foo=bar' that is not accepted as a setup function +as described above is then interpreted as an environment variable to +be set. A (useless?) example would be to use `TERM=vt100' as a boot +argument. + +Any remaining arguments that were not picked up by the kernel and were +not interpreted as environment variables are then passed onto process +one, which is usually the init program. The most common argument that +is passed to the init process is the word `single' which instructs init +to boot the computer in single user mode, and not launch all the usual +daemons. Check the manual page for the version of init installed on +your system to see what arguments it accepts. + +.SH "GENERAL NON-DEVICE SPECIFIC BOOT ARGS" + +.SS "`init=...'" + +This sets the initial command to be executed by the kernel. +If this is not set, or cannot be found, the kernel will try +.IR /etc/init , +then +.IR /bin/init , +then +.IR /sbin/init , +then +.IR /bin/sh +and panic if all of this fails. + +.SS "`nfsaddrs=...'" + +This sets the nfs boot address to the given string. +This boot address is used in case of a net boot. + +.SS "`nfsroot=...'" + +This sets the nfs root name to the given string. If this string +does not begin with '/' or ',' or a digit, then it is prefixed by +`/tftpboot/'. This root name is used in case of a net boot. + +.SS "`no387'" + +(Only when CONFIG_BUGi386 is defined.) +Some i387 coprocessor chips have bugs that show up when used in 32 bit +protected mode. For example, some of the early ULSI-387 chips would +cause solid lockups while performing floating point calculations. +Using the `no387' boot arg causes Linux to ignore the maths +coprocessor even if you have one. Of course you must then have your +kernel compiled with math emulation support! + +.SS "`no-hlt'" + +(Only when CONFIG_BUGi386 is defined.) +Some of the early i486DX-100 chips have a problem with the `hlt' +instruction, in that they can't reliably return to operating mode +after this instruction is used. Using the `no-hlt' instruction tells +Linux to just run an infinite loop when there is nothing else to do, +and to not halt the CPU. This allows people with these broken chips +to use Linux. + +.SS "`root=...'" + +This argument tells the kernel what device is to be used as the root +filesystem while booting. The default of this setting is determined +at compile time, and usually is the value of the root device of the +system that the kernel was built on. To override this value, and +select the second floppy drive as the root device, one would +use `root=/dev/fd1'. (The root device can also be set using +.BR rdev (8).) + +The root device can be specified symbolically or numerically. +A symbolic specification has the form /dev/XXYN, where XX designates +the device type (`hd' for ST-506 compatible hard disk, with Y in +`a'-`d'; `sd' for SCSI compatible disk, with Y in `a'-`e'; +`ad' for Atari ACSI disk, with Y in `a'-`e', +`ez' for a Syquest EZ135 parallel port removable drive, with Y=`a', +`xd' for XT compatible disk, with Y either `a' or `b'; `fd' for +floppy disk, with Y the floppy drive number - fd0 would be +the DOS `A:' drive, and fd1 would be `B:'), Y the driver letter or +number, and N the number (in decimal) of the partition on this device +(absent in the case of floppies). Recent kernels allow many other +types, mostly for CD-ROMs: nfs, ram, scd, mcd, cdu535, aztcd, cm206cd, +gscd, sbpcd, sonycd, bpcd. +(The type nfs specifies a net boot; ram refers to a ram disk.) + +Note that this has nothing to do with the designation of these +devices on your file system. The `/dev/' part is purely conventional. + +The more awkward and less portable numeric specification of the above +possible root devices in major/minor format is also accepted. (E.g., +/dev/sda3 is major 8, minor 3, so you could use `root=0x803' as an +alternative.) + +.SS "`ro' and `rw'" + +The `ro' option tells the kernel to mount the root filesystem +as `readonly' so that filesystem consistency check programs (fsck) +can do their work on a quiescent file system. No processes can +write to files on the filesystem in question until it is `remounted' +as read/write capable, e.g., by `mount -w -n -o remount /'. +(See also +.BR mount (8).) + +The `rw' option tells the kernel to mount the root filesystem read/write. +This is the default. + +The choice between read-only and read/write can also be set using +.BR rdev (8). + +.SS "`reserve=...'" + +This is used to protect I/O port regions from probes. The form of the +command is: +.IP +.BI reserve= iobase,extent[,iobase,extent]... +.LP +In some machines it may be necessary to prevent device drivers from +checking for devices (auto-probing) in a specific region. This may be +because of hardware that reacts badly to the probing, or hardware +that would be mistakenly identified, or merely +hardware you don't want the kernel to initialize. + +The reserve boot-time argument specifies an I/O port region that +shouldn't be probed. A device driver will not probe a reserved region, +unless another boot argument explicitly specifies that it do so. + +For example, the boot line +.IP +reserve=0x300,32 blah=0x300 +.LP +keeps all device drivers except the driver for `blah' from probing +0x300-0x31f. + +.SS "`mem=...'" + +The BIOS call defined in the PC specification that returns +the amount of installed memory was only designed to be able +to report up to 64MB. Linux uses this BIOS call at boot to +determine how much memory is installed. If you have more than 64MB of +RAM installed, you can use this boot arg to tell Linux how much memory +you have. The value is in decimal or hexadecimal (prefix 0x), +and the suffixes `k' (times 1024) or `M' (times 1048576) can be used. +Here is a quote from Linus on usage of the `mem=' parameter. + +\&``The kernel will accept any `mem=xx' parameter you give it, and if it +turns out that you lied to it, it will crash horribly sooner or later. +The parameter indicates the highest addressable RAM address, so +\&`mem=0x1000000' means you have 16MB of memory, for example. For a +96MB machine this would be `mem=0x6000000'. + +NOTE NOTE NOTE: some machines might use the top of memory for BIOS +cacheing or whatever, so you might not actually have up to the full +96MB addressable. The reverse is also true: some chipsets will map +the physical memory that is covered by the BIOS area into the area +just past the top of memory, so the top-of-mem might actually be 96MB ++ 384kB for example. If you tell linux that it has more memory than +it actually does have, bad things will happen: maybe not at once, but +surely eventually.'' + +.SS "`panic=N'" +By default the kernel will not reboot after a panic, but this option +will cause a kernel reboot after N seconds (if N > 0). +This panic timeout can also be set by "echo N > /proc/sys/kernel/panic". + +.SS "`reboot=[warm|cold][,[bios|hard]]'" +(Only when CONFIG_BUGi386 is defined.) +Since 2.0.22 a reboot is by default a cold reboot. +One asks for the old default with `reboot=warm'. +(A cold reboot may be required to reset certain hardware, +but might destroy not yet written data in a disk cache. +A warm reboot may be faster.) +By default a reboot is hard, by asking the keyboard controller +to pulse the reset line low, but there is at least one type +of motherboard where that doesn't work. The option `reboot=bios' will +instead jump through the BIOS. + +.SS "`nosmp'" and "`maxcpus=N'" +(Only when __SMP__ is defined.) +A command-line option of `nosmp' or `maxcpus=0' will disable SMP +activation entirely; an option `maxcpus=N' limits the maximum number +of CPUs activated in SMP mode to N. + + +.SH "BOOT ARGUMENTS FOR USE BY KERNEL DEVELOPERS" + +.SS "`debug'" + +Kernel messages are handed off to the kernel log daemon klogd so that they +may be logged to disk. Messages with a priority above +.I console_loglevel +are also printed on the console. (For these levels, see <linux/kernel.h>.) +By default this variable is set to log anything more important than +debug messages. This boot argument will cause the kernel to also +print the messages of DEBUG priority. +The console loglevel can also be set at run time via an option +to klogd. See +.BR klogd (8). + +.SS "`profile=N'" + +It is possible to enable a kernel profiling function, +if one wishes to find out where the kernel is spending its CPU cycles. +Profiling is enabled by setting the variable +.I prof_shift +to a nonzero value. This is done either by specifying CONFIG_PROFILE at +compile time, or by giving the `profile=' option. +Now the value that +.I prof_shift +gets will be N, when given, or CONFIG_PROFILE_SHIFT, when that is given, +or 2, the default. The significance of this variable is that it +gives the granularity of the profiling: each clock tick, if the +system was executing kernel code, a counter is incremented: +.IP +profile[address >> prof_shift]++; +.LP +The raw profiling information can be read from +.IR /proc/profile . +Probably you'll want to use a tool such as readprofile.c to digest it. +Writing to +.I /proc/profile +will clear the counters. + +.SS "`swap=N1,N2,N3,N4,N5,N6,N7,N8'" +Set the eight parameters max_page_age, page_advance, page_decline, +page_initial_age, age_cluster_fract, age_cluster_min, pageout_weight, +bufferout_weight that control the kernel swap algorithm. +For kernel tuners only. + +.SS "`buff=N1,N2,N3,N4,N5,N6'" +Set the six parameters max_buff_age, buff_advance, buff_decline, +buff_initial_age, bufferout_weight, buffermem_grace that control +kernel buffer memory management. For kernel tuners only. + + + +.SH "BOOT ARGUMENTS FOR RAMDISK USE" +(Only if the kernel was compiled with CONFIG_BLK_DEV_RAM.) +In general it is a bad idea to use a ramdisk under Linux - +the system will use available memory more efficiently itself. +But while booting (or while constructing boot floppies) +it is often useful to load the floppy contents into a +ramdisk. One might also have a system in which first +some modules (for filesystem or hardware) must be loaded +before the main disk can be accessed. + +In Linux 1.3.48, ramdisk handling was changed drastically. +Earlier, the memory was allocated statically, and there was +a `ramdisk=N' parameter to tell its size. (This could also +be set in the kernel image at compile time, or by use of +.BR rdev (8).) +These days ram disks use the buffer cache, and grow dynamically. +For a lot of information (e.g., how to use +.BR rdev (8) +in conjunction with the new ramdisk setup), see +.IR /usr/src/linux/Documentation/ramdisk.txt . + +There are four parameters, two boolean and two integral. + +.SS "`load_ramdisk=N'" +If N=1, do load a ramdisk. If N=0, do not load a ramdisk. +(This is the default.) + +.SS "`prompt_ramdisk=N'" +If N=1, do prompt for insertion of the floppy. (This is the default.) +If N=0, do not prompt. (Thus, this parameter is never needed.) + +.SS "`ramdisk_size=N' or (obsolete) `ramdisk=N' +Set the maximal size of the ramdisk(s) to N kB. The default is 4096 (4 MB). + +.SS "`ramdisk_start=N'" +Sets the starting block number (the offset on the floppy where +the ramdisk starts) to N. +This is needed in case the ramdisk follows a kernel image. + +.SS "`noinitrd'" +(Only if the kernel was compiled with CONFIG_BLK_DEV_RAM +and CONFIG_BLK_DEV_INITRD.) +These days it is possible to compile the kernel to use initrd. +When this feature is enabled, the boot process will load the kernel +and an initial ramdisk; then the kernel converts initrd into +a "normal" ramdisk, which is mounted read-write as root device; +then /linuxrc is executed; afterwards the "real" root file system is mounted, +and the initrd filesystem is moved over to /initrd; finally +the usual boot sequence (e.g. invocation of /sbin/init) is performed. + +For a detailed description of the initrd feature, see +.IR /usr/src/linux/Documentation/initrd.txt . + +The `noinitrd' option tells the kernel that although it was compiled for +operation with initrd, it should not go through the above steps, but +leave the initrd data under +.IR /dev/initrd . +(This device can be used only once - the data is freed as soon as +the last process that used it has closed +.IR /dev/initrd .) + + +.SH "BOOT ARGUMENTS FOR SCSI DEVICES" + +General notation for this section: + +.I iobase +-- the first I/O port that the SCSI host occupies. These are +specified in hexidecimal notation, and usually lie in the range from +0x200 to 0x3ff. + +.I irq +-- the hardware interrupt that the card is configured to use. +Valid values will be dependent on the card in question, but will +usually be 5, 7, 9, 10, 11, 12, and 15. The other values are usually +used for common peripherals like IDE hard disks, floppies, serial +ports, etc. + +.I scsi-id +-- the ID that the host adapter uses to identify itself on the +SCSI bus. Only some host adapters allow you to change this value, as +most have it permanently specified internally. The usual default value +is 7, but the Seagate and Future Domain TMC-950 boards use 6. + +.I parity +-- whether the SCSI host adapter expects the attached devices +to supply a parity value with all information exchanges. Specifying a +one indicates parity checking is enabled, and a zero disables parity +checking. Again, not all adapters will support selection of parity +behaviour as a boot argument. + +.SS "`max_scsi_luns=...'" + +A SCSI device can have a number of `sub-devices' contained within +itself. The most common example is one of the new SCSI CD-ROMs that +handle more than one disk at a time. Each CD is addressed as a +`Logical Unit Number' (LUN) of that particular device. But most +devices, such as hard disks, tape drives and such are only one device, +and will be assigned to LUN zero. + +Some poorly designed SCSI devices cannot handle being probed for +LUNs not equal to zero. Therefore, if the compile time flag +CONFIG_SCSI_MULTI_LUN is not set, newer kernels will by default +only probe LUN zero. + +To specify the number of probed LUNs at boot, one enters +`max_scsi_luns=n' as a boot arg, where n is a number between one and +eight. To avoid problems as described above, one would use n=1 to +avoid upsetting such broken devices. + +.SS "SCSI tape configuration" + +Some boot time configuration of the SCSI tape driver can be achieved +by using the following: +.IP +.BI st= buf_size[,write_threshold[,max_bufs]] +.LP +The first two numbers are specified in units of kB. The default +.I buf_size +is 32kB, and the maximum size that can be specified is a +ridiculous 16384kB. The +.I write_threshold +is the value at which the buffer is committed to tape, with a +default value of 30kB. The maximum number of buffers varies +with the number of drives detected, and has a default of two. +An example usage would be: +.IP +st=32,30,2 +.LP +Full details can be found in the README.st file that is in the scsi +directory of the kernel source tree. + +.SS "Adaptec aha151x, aha152x, aic6260, aic6360, SB16-SCSI configuration" + +The aha numbers refer to cards and the aic numbers refer to the actual +SCSI chip on these type of cards, including the Soundblaster-16 SCSI. + +The probe code for these SCSI hosts looks for an installed BIOS, and +if none is present, the probe will not find your card. Then you will +have to use a boot arg of the form: +.IP +.BI aha152x= iobase[,irq[,scsi-id[,reconnect[,parity]]]] +.LP +If the driver was compiled with debugging enabled, a sixth +value can be specified to set the debug level. + +All the parameters are as described at the top of this section, and the +.I reconnect +value will allow device disconnect/reconnect if a non-zero value +is used. An example usage is as follows: +.IP +aha152x=0x340,11,7,1 +.LP +Note that the parameters must be specified in order, meaning that if +you want to specify a parity setting, then you will have to specify an +iobase, irq, scsi-id and reconnect value as well. + +.SS "Adaptec aha154x configuration" + +The aha1542 series cards have an i82077 floppy controller onboard, +while the aha1540 series cards do not. These are busmastering cards, +and have parameters to set the ``fairness'' that is used to share +the bus with other devices. The boot arg looks like the following. +.IP +.BI aha1542= iobase[,buson,busoff[,dmaspeed]] +.LP +Valid iobase values are usually one of: 0x130, 0x134, 0x230, 0x234, +0x330, 0x334. Clone cards may permit other values. + +The +.IR buson ", " busoff +values refer to the number of microseconds that the +card dominates the ISA bus. The defaults are 11us on, and 4us off, so +that other cards (such as an ISA LANCE Ethernet card) have a chance to +get access to the ISA bus. + +The +.I dmaspeed +value refers to the rate (in MB/s) at which the DMA +(Direct Memory Access) transfers proceed. The default is 5MB/s. +Newer revision cards allow you to select this value as part of the +soft-configuration, older cards use jumpers. You can use values up to +10MB/s assuming that your motherboard is capable of handling it. +Experiment with caution if using values over 5MB/s. + +.SS "Adaptec aha274x, aha284x, aic7xxx configuration" + +These boards can accept an argument of the form: +.IP +.BI aic7xxx= extended,no_reset +.LP +The +.I extended +value, if non-zero, indicates that extended translation for large +disks is enabled. The +.I no_reset +value, if non-zero, tells the driver not to reset the SCSI bus when +setting up the host adaptor at boot. + +.SS "AdvanSys SCSI Hosts configuration (`advansys=')" + +The AdvanSys driver can accept up to four i/o addresses that will be +probed for an AdvanSys SCSI card. Note that these values (if used) do +not effect EISA or PCI probing in any way. They are only used for +probing ISA and VLB cards. In addition, if the driver has been +compiled with debugging enabled, the level of debugging output can be +set by adding an 0xdeb[0-f] parameter. The 0-f allows setting the +level of the debugging messages to any of 16 levels of verbosity. + +.SS "AM53C974" +.IP +.BI AM53C974= host-scsi-id,target-scsi-id,max-rate,max-offset +.LP + +.SS "BusLogic SCSI Hosts configuration (`BusLogic=')" +.IP +.BI BusLogic= N1,N2,N3,N4,N5,S1,S2,... +.LP +For an extensive discussion of the BusLogic command line parameters, +see +.IR /usr/src/linux/drivers/scsi/BusLogic.c +(lines 3149-3270 in the kernel version I am looking at). The text +below is a very much abbreviated extract. + +The parameters N1-N5 are integers. The parameters S1,... are strings. +N1 is the I/O Address at which the Host Adapter is located. +N2 is the Tagged Queue Depth to use for Target Devices that support +Tagged Queuing. +N3 is the Bus Settle Time in seconds. This is the amount of time +to wait between a Host Adapter Hard Reset which +initiates a SCSI Bus Reset and issuing any SCSI Commands. +N4 is the Local Options (for one Host Adapter). +N5 is the Global Options (for all Host Adapters). + +The string options are used to provide control over Tagged Queuing +(TQ:Default, TQ:Enable, TQ:Disable, TQ:<Per-Target-Spec>), over +Error Recovery (ER:Default, ER:HardReset, ER:BusDeviceReset, +ER:None, ER:<Per-Target-Spec>), and over Host Adapter Probing +(NoProbe, NoProbeISA, NoSortPCI). + +.SS "EATA/DMA configuration" +The default list of i/o ports to be probed can be changed by +.IP +.BI eata= iobase,iobase,... . +.LP + +.SS "Future Domain TMC-16x0 configuration" +.IP +.BI fdomain= iobase,irq[,adapter_id] +.LP + +.SS "Great Valley Products (GVP) SCSI controller configuration" +.IP +.BI gvp11= dma_transfer_bitmask +.LP + +.SS "Future Domain TMC-8xx, TMC-950 configuration" +.IP +.BI tmc8xx= mem_base,irq +.LP +The +.I mem_base +value is the value of the memory mapped I/O region that +the card uses. This will usually be one of the following values: +0xc8000, 0xca000, 0xcc000, 0xce000, 0xdc000, 0xde000. + +.SS "IN2000 configuration" +.IP +.BI in2000= S +.LP +where S is a comma-separated string of items keyword[:value]. +Recognized keywords (possibly with value) are: +ioport:addr, noreset, nosync:x, period:ns, disconnect:x, +debug:x, proc:x. For the function of these parameters, see +.IR /usr/src/linux/drivers/scsi/in2000.c . + +.SS "NCR5380 and NCR53C400 configuration" +The boot arg is of the form +.IP +.BI ncr5380= iobase,irq,dma +.LP +or +.IP +.BI ncr53c400= iobase,irq +.LP +If the card doesn't use interrupts, then an IRQ value of 255 (0xff) will +disable interrupts. An IRQ value of 254 means to autoprobe. More +details can be found in the file +.IR /usr/src/linux/drivers/scsi/README.g_NCR5380 . + +.SS "NCR53C8xx configuration" +.IP +.BI ncr53c8xx= S +.LP +where S is a comma-separated string of items keyword:value. +Recognized keywords are: mpar (master_parity), spar (scsi_parity), +disc (disconnection), specf (special_features), ultra (ultra_scsi), +fsn (force_sync_nego), tags (default_tags), sync (default_sync), +verb (verbose), debug (debug), burst (burst_max). +For the function of the assigned values, see +.IR /usr/src/linux/drivers/scsi/ncr53c8xx.c . + +.SS "NCR53c406a configuration" +.IP +.BI ncr53c406a= iobase[,irq[,fastpio]] +.LP +Specify irq = 0 for non-interrupt driven mode. +Set fastpio = 1 for fast pio mode, 0 for slow mode. + +.SS "Pro Audio Spectrum configuration" + +The PAS16 uses a NC5380 SCSI chip, and newer models support +jumperless configuration. The boot arg is of the form: +.IP +.BI pas16= iobase,irq +.LP +The only difference is that you can specify an IRQ value of 255, which +will tell the driver to work without using interrupts, albeit at a +performance loss. The iobase is usually 0x388. + +.SS "Seagate ST-0x configuration" + +If your card is not detected at boot time, +you will then have to use a boot arg of the form: +.IP +.BI st0x= mem_base,irq +.LP +The +.I mem_base +value is the value of the memory mapped I/O region that +the card uses. This will usually be one of the following values: +0xc8000, 0xca000, 0xcc000, 0xce000, 0xdc000, 0xde000. + +.SS "Trantor T128 configuration" + +These cards are also based on the NCR5380 chip, and accept the +following options: +.IP +.BI t128= mem_base,irq +.LP +The valid values for +.I mem_base +are as follows: 0xcc000, 0xc8000, 0xdc000, 0xd8000. + +.SS "UltraStor 14F/34F configuration" +The default list of i/o ports to be probed can be changed by +.IP +.BI eata= iobase,iobase,... . +.LP + +.SS "WD7000 configuration" +.IP +.BI wd7000= irq,dma,iobase +.LP + +.SS "Commodore Amiga A2091/590 SCSI controller configuration" +.IP +.BI wd33c93= S +.LP +where S is a comma-separated string of options. Recognized options are +nosync:bitmask, nodma:x, period:ns, disconnect:x, debug:x, +clock:x, next. For details, see +.IR /usr/src/linux/drivers/scsi/wd33c93.c . + +.SH "HARD DISKS" + +.SS "IDE Disk/CD-ROM Driver Parameters" + +The IDE driver accepts a number of parameters, which range from disk +geometry specifications, to support for broken controller chips. Drive +specific options are specified by using `hdX=' with X in `a'-`h'. + +Non-drive specific options are specified with the prefix `hd='. Note +that using a drive specific prefix for a non-drive specific option +will still work, and the option will just be applied as expected. + +Also note that `hd=' can be used to refer to the next unspecified +drive in the (a, ..., h) sequence. For the following discussions, +the `hd=' option will be cited for brevity. See the file +README.ide in linux/drivers/block for more details. + +.SS "The `hd=cyls,heads,sects[,wpcom[,irq]]' options" + +These options are used to specify the physical geometry of the disk. +Only the first three values are required. The cylinder/head/sectors +values will be those used by fdisk. The write precompensation value +is ignored for IDE disks. The IRQ value specified will be the IRQ +used for the interface that the drive resides on, and is not really a +drive specific parameter. + +.SS "The `hd=serialize' option" + +The dual IDE interface CMD-640 chip is broken as designed such that +when drives on the secondary interface are used at the same time as +drives on the primary interface, it will corrupt your data. Using this +option tells the driver to make sure that both interfaces are never +used at the same time. + +.SS "The `hd=dtc2278' option" + +This option tells the driver that you have a DTC-2278D IDE interface. +The driver then tries to do DTC specific operations to enable the +second interface and to enable faster transfer modes. + +.SS "The `hd=noprobe' option" + +Do not probe for this drive. For example, +.IP +hdb=noprobe hdb=1166,7,17 +.LP +would disable the probe, but still specify the drive geometry so +that it would be registered as a valid block device, and hence +usable. + +.SS "The `hd=nowerr' option" + +Some drives apparently have the WRERR_STAT bit stuck on permanently. +This enables a work-around for these broken devices. + +.SS "The `hd=cdrom' option" + +This tells the IDE driver that there is an ATAPI compatible CD-ROM +attached in place of a normal IDE hard disk. In most cases the CD-ROM +is identified automatically, but if it isn't then this may help. + +.SS "Standard ST-506 Disk Driver Options (`hd=')" + +The standard disk driver can accept geometry arguments for the disks +similar to the IDE driver. Note however that it only expects three +values (C/H/S) -- any more or any less and it will silently ignore +you. Also, it only accepts `hd=' as an argument, i.e. `hda=' +and so on are not valid here. The format is as follows: +.IP +hd=cyls,heads,sects +.LP +If there are two disks installed, the above is repeated with the +geometry parameters of the second disk. + +.SS "XT Disk Driver Options (`xd=')" + +If you are unfortunate enough to be using one of these old 8 bit cards +that move data at a whopping 125kB/s then here is the scoop. +If the card is not recognised, you will have to use a boot arg of the form: +.IP +xd=type,irq,iobase,dma_chan +.LP +The type value specifies the particular manufacturer of the card, +overriding autodetection. For the types to use, consult the +.I drivers/block/xd.c +source file of the kernel you are using. The type is an index in the list +.I xd_sigs +and in the course of time +.\" 1.1.50, 1.3.81, 1.3.99, 2.0.34, 2.1.67, 2.1.78, 2.1.127 +types have been added to or deleted from the middle of the list, +changing all type numbers. Today (Linux 2.5.0) the types are +0=generic; 1=DTC 5150cx; 2,3=DTC 5150x; 4,5=Western Digital; +6,7,8=Seagate; 9=Omti; 10=XEBEC, and where here several types are +given with the same designation, they are equivalent. + +The xd_setup() function does no checking on the values, and assumes +that you entered all four values. Don't disappoint it. Here is an +example usage for a WD1002 controller with the BIOS disabled/removed, +using the `default' XT controller parameters: +.IP +xd=2,5,0x320,3 +.LP + +.SS "Syquest's EZ* removable disks" +.IP +.BI ez= iobase[,irq[,rep[,nybble]]] +.LP + +.SH "IBM MCA BUS DEVICES" +See also +.IR /usr/src/linux/Documentation/mca.txt . + +.SS "PS/2 ESDI hard disks" +It is possible to specify the desired geometry at boot time: +.IP +.BI ed= cyls,heads,sectors. +.LP +For a ThinkPad-720, add the option +.IP +.BR tp720=1 . +.LP + +.SS "IBM Microchannel SCSI Subsystem configuration" +.IP +.BI ibmmcascsi= N +.LP +where N is the \fIpun\fP (SCSI ID) of the subsystem. + +.SH "CD-ROMs (Non-SCSI/ATAPI/IDE)" + +.SS "The Aztech Interface" + +The syntax for this type of card is: +.IP +aztcd=iobase[,magic_number] +.LP +If you set the magic_number to 0x79 then the driver will try and run +anyway in the event of an unknown firmware version. All other values +are ignored. + +.SS "Parallel port CD-ROM drives" +Syntax: +.IP +pcd.driveN=prt,pro,uni,mod,slv,dly +.br +pcd.nice=nice +.LP +where `port' is the base address, `pro' is the protocol number, `uni' +is the unit selector (for chained devices), `mod' is the mode (or -1 +to choose the best automatically), `slv' is 1 if it should be a slave, +and `dly' is a small integer for slowing down port accesses. The +`nice' parameter controls the driver's use of idle CPU time, at the +expense of some speed. + +.SS "The CDU-31A and CDU-33A Sony Interface" + +This CD-ROM interface is found on some of the Pro Audio Spectrum sound +cards, and other Sony supplied interface cards. The syntax is as +follows: +.IP +cdu31a=iobase,[irq[,is_pas_card]] +.LP +Specifying an IRQ value of zero tells the driver that hardware +interrupts aren't supported (as on some PAS cards). If your card +supports interrupts, you should use them as it cuts down on the CPU +usage of the driver. + +The +.I is_pas_card +should be entered as `PAS' if using a Pro Audio Spectrum card, +and otherwise it should not be specified at all. + +.SS "The CDU-535 Sony Interface" + +The syntax for this CD-ROM interface is: +.IP +sonycd535=iobase[,irq] +.LP +A zero can be used for the I/O base as a `placeholder' if one wishes +to specify an IRQ value. + +.SS "The GoldStar Interface" + +The syntax for this CD-ROM interface is: +.IP +gscd=iobase +.LP + +.SS "The ISP16 CD-ROM Interface" +Syntax: +.IP +isp16=[iobase[,irq[,dma[,type]]]] +.LP +(three integers and a string). If the type is given as `noisp16', +the interface will not be configured. Other recognized types +are: `Sanyo", `Sony', `Panasonic' and `Mitsumi'. + +.SS "The Mitsumi Standard Interface" + +The syntax for this CD-ROM interface is: +.IP +mcd=iobase,[irq[,wait_value]] +.LP +The +.I wait_value +is used as an internal timeout value for people who are +having problems with their drive, and may or may not be implemented +depending on a compile time #define. +The Mitsumi FX400 is an IDE/ATAPI CD-ROM player and does not use +the mcd driver. + +.SS "The Mitsumi XA/MultiSession Interface" + +This is for the same hardware as above, but the driver has extended features. +Syntax: +.IP +mcdx=iobase[,irq] +.LP + +.SS "The Optics Storage Interface" + +The syntax for this type of card is: +.IP +optcd=iobase +.LP + +.SS "The Phillips CM206 Interface" + +The syntax for this type of card is: +.IP +cm206=[iobase][,irq] +.LP + +The driver assumes numbers between 3 and 11 are IRQ values, and +numbers between 0x300 and 0x370 are I/O ports, so you can specify one, +or both numbers, in any order. It also accepts `cm206=auto' to enable +autoprobing. + +.SS "The Sanyo Interface" + +The syntax for this type of card is: +.IP +sjcd=iobase[,irq[,dma_channel]] +.LP + +.SS "The SoundBlaster Pro Interface" + +The syntax for this type of card is: +.IP +sbpcd=iobase,type +.LP +where type is one of the following (case sensitive) strings: +`SoundBlaster', `LaserMate', or `SPEA'. The I/O base is that of the +CD-ROM interface, and not that of the sound portion of the card. + +.SH "ETHERNET DEVICES" + +Different drivers make use of different parameters, but they all at +least share having an IRQ, an I/O port base value, and a name. In its +most generic form, it looks something like this: +.IP +ether=irq,iobase[,param_1[,...param_8]],name +.LP +The first non-numeric argument is taken as the name. The param_n +values (if applicable) usually have different meanings for each +different card/driver. Typical param_n values are used to specify +things like shared memory address, interface selection, DMA channel +and the like. + +The most common use of this parameter is to force probing for a second +ethercard, as the default is to only probe for one. This can be +accomplished with a simple: +.IP +ether=0,0,eth1 +.LP +Note that the values of zero for the IRQ and I/O base in the above +example tell the driver(s) to autoprobe. + +The Ethernet-HowTo has extensive documentation on using multiple +cards and on the card/driver specific implementation +of the param_n values where used. Interested readers should refer to +the section in that document on their particular card. + +.SH "THE FLOPPY DISK DRIVER" + +There are many floppy driver options, and they are all listed in +README.fd in linux/drivers/block. This information is taken directly +from that file. + +.SS "floppy=mask,allowed_drive_mask" + +Sets the bitmask of allowed drives to mask. By default, only units 0 +and 1 of each floppy controller are allowed. This is done because +certain non-standard hardware (ASUS PCI motherboards) mess up the +keyboard when accessing units 2 or 3. This option is somewhat +obsoleted by the cmos option. + +.SS "floppy=all_drives" + +Sets the bitmask of allowed drives to all drives. Use this if you have +more than two drives connected to a floppy controller. + +.SS "floppy=asus_pci" + +Sets the bitmask to allow only units 0 and 1. (The default) + +.SS "floppy=daring" + +Tells the floppy driver that you have a well behaved floppy +controller. This allows more efficient and smoother operation, but +may fail on certain controllers. This may speed up certain operations. + +.SS "floppy=0,daring" + +Tells the floppy driver that your floppy controller should be used +with caution. + +.SS "floppy=one_fdc" + +Tells the floppy driver that you have only floppy controller (default) + +.SS "floppy=two_fdc or floppy=address,two_fdc" + +Tells the floppy driver that you have two floppy controllers. The +second floppy controller is assumed to be at address. If address is +not given, 0x370 is assumed. + +.SS "floppy=thinkpad" + +Tells the floppy driver that you have a Thinkpad. Thinkpads use an +inverted convention for the disk change line. + +.SS "floppy=0,thinkpad" + +Tells the floppy driver that you don't have a Thinkpad. + +.SS "floppy=drive,type,cmos" + +Sets the cmos type of drive to type. Additionally, this drive is +allowed in the bitmask. This is useful if you have more than two +floppy drives (only two can be described in the physical cmos), or if +your BIOS uses non-standard CMOS types. Setting the CMOS to 0 for the +first two drives (default) makes the floppy driver read the physical +cmos for those drives. + +.SS "floppy=unexpected_interrupts" + +Print a warning message when an unexpected interrupt is received +(default behaviour) + +.SS "floppy=no_unexpected_interrupts or floppy=L40SX" + +Don't print a message when an unexpected interrupt is received. This +is needed on IBM L40SX laptops in certain video modes. (There seems to +be an interaction between video and floppy. The unexpected interrupts +only affect performance, and can safely be ignored.) + +.SH "THE SOUND DRIVER" + +The sound driver can also accept boot args to override the compiled in +values. This is not recommended, as it is rather complex. It is +described in the Readme.Linux file, in linux/drivers/sound. It accepts +a boot arg of the form: +.IP +sound=device1[,device2[,device3...[,device10]]] +.LP +where each deviceN value is of the following format 0xTaaaId and the +bytes are used as follows: + +T - device type: 1=FM, 2=SB, 3=PAS, 4=GUS, 5=MPU401, 6=SB16, +7=SB16-MPU401 + +aaa - I/O address in hex. + +I - interrupt line in hex (i.e 10=a, 11=b, ...) + +d - DMA channel. + +As you can see it gets pretty messy, and you are better off to compile +in your own personal values as recommended. Using a boot arg of +`sound=0' will disable the sound driver entirely. + + +.SH "ISDN DRIVERS" + +.SS "The ICN ISDN driver" +Syntax: +.IP +icn=iobase,membase,icn_id1,icn_id2 +.LP +where icn_id1,icn_id2 are two strings used to identify the +card in kernel messages. + +.SS "The PCBIT ISDN driver" +Syntax: +.IP +pcbit=membase1,irq1[,membase2,irq2] +.LP +where membaseN is the shared memory base of the N'th card, and irqN is +the interrupt setting of the N'th card. The default is IRQ 5 and +membase 0xD0000. + +.SS "The Teles ISDN driver" +Syntax: +.IP +teles=iobase,irq,membase,protocol,teles_id +.LP +where iobase is the i/o port address of the card, membase is the +shared memory base address of the card, irq is the interrupt channel +the card uses, and teles_id is the unique ASCII string identifier. + +.SH "SERIAL PORT DRIVERS" + +.SS "The RISCom/8 Multiport Serial Driver (`riscom8=')" +Syntax: +.IP +riscom=iobase1[,iobase2[,iobase3[,iobase4]]] +.LP +More details can be found in +.IR /usr/src/linux/Documentation/riscom8.txt . + +.SS "The DigiBoard Driver (`digi=')" +If this option is used, it should have precisely six parameters. +Syntax: +.IP +digi=status,type,altpin,numports,iobase,membase +.LP +The parameters maybe given as integers, or as strings. +If strings are used, then iobase and membase should be given +in hexadecimal. +The integer arguments (fewer may be given) are in order: +status (Enable(1) or Disable(0) this card), +type (PC/Xi(0), PC/Xe(1), PC/Xeve(2), PC/Xem(3)), +altpin (Enable(1) or Disable(0) alternate pin arrangement), +numports (number of ports on this card), +iobase (I/O Port where card is configured (in HEX)), +membase (base of memory window (in HEX)). +Thus, the following two boot prompt arguments are equivalent: +.IP +digi=E,PC/Xi,D,16,200,D0000 +.br +digi=1,0,0,16,0x200,851968 +.LP +More details can be found in +.IR /usr/src/linux/Documentation/digiboard.txt . + +.SS "The Baycom Serial/Parallel Radio Modem" +Syntax: +.IP +baycom=iobase,irq,modem +.LP +There are precisely 3 parameters; for several cards, give +several `baycom=' commands. The modem parameter is a string +that can take one of the values ser12, ser12*, par96, par96*. +Here the * denotes that software DCD is to be used, and +ser12/par96 chooses between the supported modem types. +For more details, see +.IR /usr/src/linux/drivers/net/README.baycom . + +.SS "Soundcard radio modem driver" +Syntax: +.IP +soundmodem=iobase,irq,dma[,dma2[,serio[,pario]]],0,mode +.LP +All parameters except the last are integers; +the dummy 0 is required because of a bug in the setup code. +The mode parameter is a string with syntax hw:modem, +where hw is one of sbc, wss, wssfdx and modem is one of +afsk1200, fsk9600. + +.SH "THE LINE PRINTER DRIVER" + +.SS "`lp='" +Syntax: +.IP +lp=0 +.br +lp=auto +.br +lp=reset +.br +lp=port[,port...] +.LP +You can tell the printer driver what ports to use and what ports not +to use. The latter comes in handy if you don't want the printer driver +to claim all available parallel ports, so that other drivers +(e.g. PLIP, PPA) can use them instead. + +The format of the argument is multiple port names. For example, +lp=none,parport0 would use the first parallel port for lp1, and +disable lp0. To disable the printer driver entirely, one can use +lp=0. + +.SS "WDT500/501 driver" +Syntax: +.IP +wdt=io,irq +.LP + +.SH "MOUSE DRIVERS" + +.SS "`bmouse=irq'" +The busmouse driver only accepts one parameter, that being the +hardware IRQ value to be used. + +.SS "`msmouse=irq'" +And precisely the same is true for the msmouse driver. + +.SS "ATARI mouse setup" +.LP +atamouse=threshold[,y-threshold] +.IP +If only one argument is given, it is used for both +x-threshold and y-threshold. Otherwise, the first argument +is the x-threshold, and the second the y-threshold. +These values must lie between 1 and 20 (inclusive); the default is 2. + +.SH "VIDEO HARDWARE" + +.SS "`no-scroll'" +This option tells the console driver not to use hardware scroll +(where a scroll is effected by moving the screen origin in video +memory, instead of moving the data). It is required by certain +Braille machines. + +.SH AUTHORS +Linus Torvalds (and many others) + +.SH "SEE ALSO" +.BR lilo.conf (5), +.BR klogd (8), +.BR lilo (8), +.BR mount (8), +.BR rdev (8) + +Large parts of this man page have been derived from the +Boot Parameter HOWTO (version 1.0.1) written by Paul Gortmaker. +More information may be found in this (or a more recent) HOWTO. +An uptodate source of information is +.IR /usr/src/linux/Documentation/kernel-parameters.txt . |