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1 | .\" Copyright (c) 1995,1997 Paul Gortmaker and Andries Brouwer |
2 | .\" | |
1dd72f9c | 3 | .\" %%%LICENSE_START(GPLv2+_DOC_FULL) |
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4 | .\" This is free documentation; you can redistribute it and/or |
5 | .\" modify it under the terms of the GNU General Public License as | |
6 | .\" published by the Free Software Foundation; either version 2 of | |
7 | .\" the License, or (at your option) any later version. | |
8 | .\" | |
9 | .\" The GNU General Public License's references to "object code" | |
10 | .\" and "executables" are to be interpreted as the output of any | |
11 | .\" document formatting or typesetting system, including | |
12 | .\" intermediate and printed output. | |
13 | .\" | |
14 | .\" This manual is distributed in the hope that it will be useful, | |
15 | .\" but WITHOUT ANY WARRANTY; without even the implied warranty of | |
16 | .\" MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
17 | .\" GNU General Public License for more details. | |
18 | .\" | |
19 | .\" You should have received a copy of the GNU General Public | |
c715f741 MK |
20 | .\" License along with this manual; if not, see |
21 | .\" <http://www.gnu.org/licenses/>. | |
6a8d8745 | 22 | .\" %%%LICENSE_END |
fea681da MK |
23 | .\" |
24 | .\" This man page written 950814 by aeb, based on Paul Gortmaker's HOWTO | |
25 | .\" (dated v1.0.1, 15/08/95). | |
26 | .\" Major update, aeb, 970114. | |
8062a091 MK |
27 | .\" FIXME ? The use of quotes on this page is inconsistent with the |
28 | .\" rest of man-pages. | |
fea681da | 29 | .\" |
40dedbfe | 30 | .TH BOOTPARAM 7 2007-12-16 "Linux" "Linux Programmer's Manual" |
fea681da | 31 | .SH NAME |
f68512e9 | 32 | bootparam \- introduction to boot time parameters of the Linux kernel |
fea681da | 33 | .SH DESCRIPTION |
76c44d83 | 34 | The Linux kernel accepts certain 'command-line options' or 'boot time |
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35 | parameters' at the moment it is started. |
36 | In general this is used to | |
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37 | supply the kernel with information about hardware parameters that |
38 | the kernel would not be able to determine on its own, or to avoid/override | |
39 | the values that the kernel would otherwise detect. | |
40 | ||
41 | When the kernel is booted directly by the BIOS (say from a floppy to | |
40dedbfe | 42 | which you copied a kernel using 'cp zImage /dev/fd0'), |
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43 | you have no opportunity to specify any parameters. |
44 | So, in order to take advantage of this possibility you have to | |
45 | use software that is able to pass parameters, like LILO or loadlin. | |
46 | For a few parameters one can also modify the kernel image itself, | |
47 | using rdev, see | |
48 | .BR rdev (8) | |
49 | for further details. | |
50 | ||
51 | The LILO program (LInux LOader) written by Werner Almesberger is the | |
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52 | most commonly used. |
53 | It has the ability to boot various kernels, and | |
54 | stores the configuration information in a plain text file. | |
55 | (See | |
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56 | .BR lilo (8) |
57 | and | |
58 | .BR lilo.conf (5).) | |
59 | LILO can boot DOS, OS/2, Linux, FreeBSD, UnixWare, etc., and is quite flexible. | |
60 | ||
40dedbfe | 61 | The other commonly used Linux loader is 'LoadLin' which is a DOS |
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62 | program that has the capability to launch a Linux kernel from the DOS |
63 | prompt (with boot-args) assuming that certain resources are available. | |
64 | This is good for people that want to launch Linux from DOS. | |
65 | ||
66 | It is also very useful if you have certain hardware which relies on | |
c13182ef | 67 | the supplied DOS driver to put the hardware into a known state. |
40dedbfe | 68 | A common example is 'SoundBlaster Compatible' sound cards that require |
fea681da | 69 | the DOS driver to twiddle a few mystical registers to put the card |
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70 | into a SB compatible mode. |
71 | Booting DOS with the supplied driver, and | |
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72 | then loading Linux from the DOS prompt with loadlin avoids the reset |
73 | of the card that happens if one rebooted instead. | |
73d8cece | 74 | .SS The argument list |
fea681da | 75 | The kernel command line is parsed into a list of strings |
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76 | (boot arguments) separated by spaces. |
77 | Most of the boot args take the form of: | |
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78 | .IP |
79 | name[=value_1][,value_2]...[,value_10] | |
80 | .LP | |
40dedbfe | 81 | where 'name' is a unique keyword that is used to identify what part of |
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82 | the kernel the associated values (if any) are to be given to. |
83 | Note the limit of 10 is real, as the present code only handles 10 comma | |
c13182ef | 84 | separated parameters per keyword. |
3b777aff | 85 | (However, you can reuse the same |
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86 | keyword with up to an additional 10 parameters in unusually |
87 | complicated situations, assuming the setup function supports it.) | |
88 | ||
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89 | Most of the sorting goes on in linux/init/main.c. |
90 | First, the kernel | |
40dedbfe | 91 | checks to see if the argument is any of the special arguments 'root=', |
25715c96 | 92 | \&'nfsroot=', 'nfsaddrs=', 'ro', 'rw', 'debug' or 'init'. |
c13182ef | 93 | The meaning of these special arguments is described below. |
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94 | |
95 | Then it walks a list of setup functions (contained in the bootsetups | |
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96 | array) to see if the specified argument string (such as 'foo') has |
97 | been associated with a setup function ('foo_setup()') for a particular | |
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98 | device or part of the kernel. |
99 | If you passed the kernel the line | |
fea681da | 100 | foo=3,4,5,6 then the kernel would search the bootsetups array to see |
40dedbfe | 101 | if 'foo' was registered. |
c13182ef | 102 | If it was, then it would call the setup |
40dedbfe | 103 | function associated with 'foo' (foo_setup()) and hand it the arguments |
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104 | 3, 4, 5 and 6 as given on the kernel command line. |
105 | ||
40dedbfe | 106 | Anything of the form 'foo=bar' that is not accepted as a setup function |
fea681da | 107 | as described above is then interpreted as an environment variable to |
c13182ef | 108 | be set. |
40dedbfe | 109 | A (useless?) example would be to use 'TERM=vt100' as a boot |
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110 | argument. |
111 | ||
112 | Any remaining arguments that were not picked up by the kernel and were | |
113 | not interpreted as environment variables are then passed onto process | |
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114 | one, which is usually the init program. |
115 | The most common argument that | |
40dedbfe | 116 | is passed to the init process is the word 'single' which instructs init |
fea681da | 117 | to boot the computer in single user mode, and not launch all the usual |
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118 | daemons. |
119 | Check the manual page for the version of init installed on | |
fea681da | 120 | your system to see what arguments it accepts. |
73d8cece | 121 | .SS General non-device specific boot arguments |
bebbbd1f | 122 | .TP |
40dedbfe | 123 | .B "'init=...'" |
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124 | This sets the initial command to be executed by the kernel. |
125 | If this is not set, or cannot be found, the kernel will try | |
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126 | .IR /sbin/init , |
127 | then | |
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128 | .IR /etc/init , |
129 | then | |
130 | .IR /bin/init , | |
131 | then | |
0daa9e92 | 132 | .I /bin/sh |
fea681da | 133 | and panic if all of this fails. |
bebbbd1f | 134 | .TP |
40dedbfe | 135 | .B "'nfsaddrs=...'" |
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136 | This sets the nfs boot address to the given string. |
137 | This boot address is used in case of a net boot. | |
bebbbd1f | 138 | .TP |
40dedbfe | 139 | .B "'nfsroot=...'" |
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140 | This sets the nfs root name to the given string. |
141 | If this string | |
fea681da | 142 | does not begin with '/' or ',' or a digit, then it is prefixed by |
25715c96 | 143 | \&'/tftpboot/'. |
c13182ef | 144 | This root name is used in case of a net boot. |
bebbbd1f | 145 | .TP |
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146 | .B "'no387'" |
147 | (Only when | |
148 | .B CONFIG_BUGi386 | |
149 | is defined.) | |
fea681da | 150 | Some i387 coprocessor chips have bugs that show up when used in 32 bit |
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151 | protected mode. |
152 | For example, some of the early ULSI-387 chips would | |
c45bd688 | 153 | cause solid lockups while performing floating-point calculations. |
40dedbfe | 154 | Using the 'no387' boot arg causes Linux to ignore the maths |
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155 | coprocessor even if you have one. |
156 | Of course you must then have your | |
fea681da | 157 | kernel compiled with math emulation support! |
bebbbd1f | 158 | .TP |
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159 | .B "'no-hlt'" |
160 | (Only when | |
161 | .B CONFIG_BUGi386 | |
162 | is defined.) | |
163 | Some of the early i486DX-100 chips have a problem with the 'hlt' | |
fea681da | 164 | instruction, in that they can't reliably return to operating mode |
c13182ef | 165 | after this instruction is used. |
40dedbfe | 166 | Using the 'no-hlt' instruction tells |
fea681da | 167 | Linux to just run an infinite loop when there is nothing else to do, |
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168 | and to not halt the CPU. |
169 | This allows people with these broken chips | |
fea681da | 170 | to use Linux. |
bebbbd1f | 171 | .TP |
40dedbfe | 172 | .B "'root=...'" |
fea681da | 173 | This argument tells the kernel what device is to be used as the root |
24d01c53 | 174 | file system while booting. |
c13182ef | 175 | The default of this setting is determined |
fea681da | 176 | at compile time, and usually is the value of the root device of the |
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177 | system that the kernel was built on. |
178 | To override this value, and | |
fea681da | 179 | select the second floppy drive as the root device, one would |
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180 | use 'root=/dev/fd1'. |
181 | (The root device can also be set using | |
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182 | .BR rdev (8).) |
183 | ||
184 | The root device can be specified symbolically or numerically. | |
185 | A symbolic specification has the form /dev/XXYN, where XX designates | |
40dedbfe | 186 | the device type ('hd' for ST-506 compatible hard disk, with Y in |
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187 | \&'a'-'d'; 'sd' for SCSI compatible disk, with Y in 'a'-'e'; |
188 | \&'ad' for Atari ACSI disk, with Y in 'a'-'e', | |
189 | \&'ez' for a Syquest EZ135 parallel port removable drive, with Y='a', | |
190 | \&'xd' for XT compatible disk, with Y either 'a' or 'b'; 'fd' for | |
5503c85e | 191 | floppy disk, with Y the floppy drive number\(emfd0 would be |
40dedbfe | 192 | the DOS 'A:' drive, and fd1 would be 'B:'), Y the driver letter or |
fea681da | 193 | number, and N the number (in decimal) of the partition on this device |
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194 | (absent in the case of floppies). |
195 | Recent kernels allow many other | |
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196 | types, mostly for CD-ROMs: nfs, ram, scd, mcd, cdu535, aztcd, cm206cd, |
197 | gscd, sbpcd, sonycd, bpcd. | |
198 | (The type nfs specifies a net boot; ram refers to a ram disk.) | |
199 | ||
200 | Note that this has nothing to do with the designation of these | |
c13182ef | 201 | devices on your file system. |
40dedbfe | 202 | The '/dev/' part is purely conventional. |
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203 | |
204 | The more awkward and less portable numeric specification of the above | |
c13182ef | 205 | possible root devices in major/minor format is also accepted. |
40dedbfe | 206 | (E.g., /dev/sda3 is major 8, minor 3, so you could use 'root=0x803' as an |
fea681da | 207 | alternative.) |
bebbbd1f | 208 | .TP |
40dedbfe | 209 | .BR 'ro' " and " 'rw' |
24d01c53 | 210 | The 'ro' option tells the kernel to mount the root file system |
415d4dd0 | 211 | as 'read-only' so that file system consistency check programs (fsck) |
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212 | can do their work on a quiescent file system. |
213 | No processes can | |
24d01c53 | 214 | write to files on the file system in question until it is 'remounted' |
40dedbfe | 215 | as read/write capable, for example, by 'mount \-w \-n \-o remount /'. |
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216 | (See also |
217 | .BR mount (8).) | |
218 | ||
24d01c53 | 219 | The 'rw' option tells the kernel to mount the root file system read/write. |
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220 | This is the default. |
221 | ||
222 | The choice between read-only and read/write can also be set using | |
223 | .BR rdev (8). | |
bebbbd1f | 224 | .TP |
40dedbfe | 225 | .B "'reserve=...'" |
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226 | This is used to protect I/O port regions from probes. |
227 | The form of the command is: | |
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228 | .IP |
229 | .BI reserve= iobase,extent[,iobase,extent]... | |
bebbbd1f | 230 | .sp |
fea681da | 231 | In some machines it may be necessary to prevent device drivers from |
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232 | checking for devices (auto-probing) in a specific region. |
233 | This may be | |
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234 | because of hardware that reacts badly to the probing, or hardware |
235 | that would be mistakenly identified, or merely | |
236 | hardware you don't want the kernel to initialize. | |
237 | ||
238 | The reserve boot-time argument specifies an I/O port region that | |
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239 | shouldn't be probed. |
240 | A device driver will not probe a reserved region, | |
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241 | unless another boot argument explicitly specifies that it do so. |
242 | ||
243 | For example, the boot line | |
244 | .IP | |
245 | reserve=0x300,32 blah=0x300 | |
bebbbd1f | 246 | .IP |
40dedbfe | 247 | keeps all device drivers except the driver for 'blah' from probing |
94e9d9fe | 248 | 0x300\-0x31f. |
bebbbd1f | 249 | .TP |
40dedbfe | 250 | .B "'mem=...'" |
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251 | The BIOS call defined in the PC specification that returns |
252 | the amount of installed memory was only designed to be able | |
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253 | to report up to 64MB. |
254 | Linux uses this BIOS call at boot to | |
255 | determine how much memory is installed. | |
256 | If you have more than 64MB of | |
fea681da | 257 | RAM installed, you can use this boot arg to tell Linux how much memory |
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258 | you have. |
259 | The value is in decimal or hexadecimal (prefix 0x), | |
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260 | and the suffixes 'k' (times 1024) or 'M' (times 1048576) can be used. |
261 | Here is a quote from Linus on usage of the 'mem=' parameter. | |
fea681da | 262 | |
324633ae | 263 | .in +0.5i |
40dedbfe | 264 | The kernel will accept any 'mem=xx' parameter you give it, and if it |
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265 | turns out that you lied to it, it will crash horribly sooner or later. |
266 | The parameter indicates the highest addressable RAM address, so | |
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267 | \&'mem=0x1000000' means you have 16MB of memory, for example. |
268 | For a 96MB machine this would be 'mem=0x6000000'. | |
fea681da | 269 | |
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270 | .BR NOTE : |
271 | some machines might use the top of memory for BIOS | |
4f9d18f8 | 272 | caching or whatever, so you might not actually have up to the full |
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273 | 96MB addressable. |
274 | The reverse is also true: some chipsets will map | |
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275 | the physical memory that is covered by the BIOS area into the area |
276 | just past the top of memory, so the top-of-mem might actually be 96MB | |
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277 | + 384kB for example. |
278 | If you tell linux that it has more memory than | |
fea681da | 279 | it actually does have, bad things will happen: maybe not at once, but |
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280 | surely eventually. |
281 | .in | |
fea681da | 282 | |
40dedbfe | 283 | You can also use the boot argument 'mem=nopentium' to turn off 4 MB |
eb1af896 | 284 | page tables on kernels configured for IA32 systems with a pentium or newer |
441082ad | 285 | CPU. |
bebbbd1f | 286 | .TP |
40dedbfe | 287 | .B "'panic=N'" |
fea681da | 288 | By default the kernel will not reboot after a panic, but this option |
f7ceac86 | 289 | will cause a kernel reboot after N seconds (if N is greater than zero). |
fea681da | 290 | This panic timeout can also be set by "echo N > /proc/sys/kernel/panic". |
bebbbd1f | 291 | .TP |
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292 | .B "'reboot=[warm|cold][,[bios|hard]]'" |
293 | (Only when | |
294 | .B CONFIG_BUGi386 | |
295 | is defined.) | |
fea681da | 296 | Since 2.0.22 a reboot is by default a cold reboot. |
40dedbfe | 297 | One asks for the old default with 'reboot=warm'. |
fea681da MK |
298 | (A cold reboot may be required to reset certain hardware, |
299 | but might destroy not yet written data in a disk cache. | |
300 | A warm reboot may be faster.) | |
301 | By default a reboot is hard, by asking the keyboard controller | |
302 | to pulse the reset line low, but there is at least one type | |
c13182ef | 303 | of motherboard where that doesn't work. |
40dedbfe | 304 | The option 'reboot=bios' will |
fea681da | 305 | instead jump through the BIOS. |
bebbbd1f | 306 | .TP |
40dedbfe | 307 | .BR 'nosmp' " and " 'maxcpus=N' |
fea681da | 308 | (Only when __SMP__ is defined.) |
40dedbfe MK |
309 | A command-line option of 'nosmp' or 'maxcpus=0' will disable SMP |
310 | activation entirely; an option 'maxcpus=N' limits the maximum number | |
fea681da | 311 | of CPUs activated in SMP mode to N. |
73d8cece | 312 | .SS Boot arguments for use by kernel developers |
bebbbd1f | 313 | .TP |
40dedbfe | 314 | .B "'debug'" |
fea681da | 315 | Kernel messages are handed off to the kernel log daemon klogd so that they |
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316 | may be logged to disk. |
317 | Messages with a priority above | |
fea681da | 318 | .I console_loglevel |
c13182ef | 319 | are also printed on the console. |
c84371c6 | 320 | (For these levels, see \fI<linux/kernel.h>\fP.) |
fea681da | 321 | By default this variable is set to log anything more important than |
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322 | debug messages. |
323 | This boot argument will cause the kernel to also | |
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324 | print the messages of DEBUG priority. |
325 | The console loglevel can also be set at run time via an option | |
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326 | to klogd. |
327 | See | |
fea681da | 328 | .BR klogd (8). |
bebbbd1f | 329 | .TP |
40dedbfe | 330 | .B "'profile=N'" |
fea681da MK |
331 | It is possible to enable a kernel profiling function, |
332 | if one wishes to find out where the kernel is spending its CPU cycles. | |
333 | Profiling is enabled by setting the variable | |
334 | .I prof_shift | |
c7094399 | 335 | to a nonzero value. |
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336 | This is done either by specifying |
337 | .B CONFIG_PROFILE | |
338 | at compile time, or by giving the 'profile=' option. | |
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339 | Now the value that |
340 | .I prof_shift | |
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341 | gets will be N, when given, or |
342 | .BR CONFIG_PROFILE_SHIFT , | |
343 | when that is given, or 2, the default. | |
c13182ef | 344 | The significance of this variable is that it |
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345 | gives the granularity of the profiling: each clock tick, if the |
346 | system was executing kernel code, a counter is incremented: | |
347 | .IP | |
348 | profile[address >> prof_shift]++; | |
bebbbd1f | 349 | .sp |
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350 | The raw profiling information can be read from |
351 | .IR /proc/profile . | |
352 | Probably you'll want to use a tool such as readprofile.c to digest it. | |
353 | Writing to | |
354 | .I /proc/profile | |
355 | will clear the counters. | |
bebbbd1f | 356 | .TP |
40dedbfe | 357 | .B "'swap=N1,N2,N3,N4,N5,N6,N7,N8'" |
fea681da MK |
358 | Set the eight parameters max_page_age, page_advance, page_decline, |
359 | page_initial_age, age_cluster_fract, age_cluster_min, pageout_weight, | |
360 | bufferout_weight that control the kernel swap algorithm. | |
361 | For kernel tuners only. | |
bebbbd1f | 362 | .TP |
40dedbfe | 363 | .B "'buff=N1,N2,N3,N4,N5,N6'" |
fea681da MK |
364 | Set the six parameters max_buff_age, buff_advance, buff_decline, |
365 | buff_initial_age, bufferout_weight, buffermem_grace that control | |
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366 | kernel buffer memory management. |
367 | For kernel tuners only. | |
73d8cece | 368 | .SS Boot arguments for ramdisk use |
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369 | (Only if the kernel was compiled with |
370 | .BR CONFIG_BLK_DEV_RAM .) | |
5503c85e MK |
371 | In general it is a bad idea to use a ramdisk under Linux\(emthe |
372 | system will use available memory more efficiently itself. | |
fea681da MK |
373 | But while booting (or while constructing boot floppies) |
374 | it is often useful to load the floppy contents into a | |
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375 | ramdisk. |
376 | One might also have a system in which first | |
24d01c53 | 377 | some modules (for file system or hardware) must be loaded |
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378 | before the main disk can be accessed. |
379 | ||
380 | In Linux 1.3.48, ramdisk handling was changed drastically. | |
381 | Earlier, the memory was allocated statically, and there was | |
40dedbfe | 382 | a 'ramdisk=N' parameter to tell its size. |
c13182ef | 383 | (This could also |
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384 | be set in the kernel image at compile time, or by use of |
385 | .BR rdev (8).) | |
386 | These days ram disks use the buffer cache, and grow dynamically. | |
387 | For a lot of information (e.g., how to use | |
388 | .BR rdev (8) | |
389 | in conjunction with the new ramdisk setup), see | |
390 | .IR /usr/src/linux/Documentation/ramdisk.txt . | |
391 | ||
392 | There are four parameters, two boolean and two integral. | |
bebbbd1f | 393 | .TP |
40dedbfe | 394 | .B "'load_ramdisk=N'" |
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395 | If N=1, do load a ramdisk. |
396 | If N=0, do not load a ramdisk. | |
fea681da | 397 | (This is the default.) |
bebbbd1f | 398 | .TP |
40dedbfe | 399 | .B "'prompt_ramdisk=N'" |
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400 | If N=1, do prompt for insertion of the floppy. |
401 | (This is the default.) | |
402 | If N=0, do not prompt. | |
403 | (Thus, this parameter is never needed.) | |
bebbbd1f | 404 | .TP |
40dedbfe | 405 | .BR 'ramdisk_size=N' " or (obsolete) " 'ramdisk=N' |
c13182ef MK |
406 | Set the maximal size of the ramdisk(s) to N kB. |
407 | The default is 4096 (4 MB). | |
bebbbd1f | 408 | .TP |
40dedbfe | 409 | .B "'ramdisk_start=N'" |
fea681da MK |
410 | Sets the starting block number (the offset on the floppy where |
411 | the ramdisk starts) to N. | |
412 | This is needed in case the ramdisk follows a kernel image. | |
bebbbd1f | 413 | .TP |
40dedbfe MK |
414 | .B "'noinitrd'" |
415 | (Only if the kernel was compiled with | |
416 | .B CONFIG_BLK_DEV_RAM | |
417 | and | |
418 | .BR CONFIG_BLK_DEV_INITRD .) | |
fea681da MK |
419 | These days it is possible to compile the kernel to use initrd. |
420 | When this feature is enabled, the boot process will load the kernel | |
421 | and an initial ramdisk; then the kernel converts initrd into | |
422 | a "normal" ramdisk, which is mounted read-write as root device; | |
5fab2e7c | 423 | then /linuxrc is executed; afterward the "real" root file system is mounted, |
24d01c53 | 424 | and the initrd file system is moved over to /initrd; finally |
75b94dc3 | 425 | the usual boot sequence (e.g., invocation of /sbin/init) is performed. |
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426 | |
427 | For a detailed description of the initrd feature, see | |
428 | .IR /usr/src/linux/Documentation/initrd.txt . | |
429 | ||
40dedbfe | 430 | The 'noinitrd' option tells the kernel that although it was compiled for |
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431 | operation with initrd, it should not go through the above steps, but |
432 | leave the initrd data under | |
433 | .IR /dev/initrd . | |
4d9b6984 | 434 | (This device can be used only once: the data is freed as soon as |
fea681da MK |
435 | the last process that used it has closed |
436 | .IR /dev/initrd .) | |
73d8cece | 437 | .SS Boot arguments for SCSI devices |
fea681da MK |
438 | General notation for this section: |
439 | ||
440 | .I iobase | |
c13182ef MK |
441 | -- the first I/O port that the SCSI host occupies. |
442 | These are specified in hexadecimal notation, | |
443 | and usually lie in the range from 0x200 to 0x3ff. | |
fea681da MK |
444 | |
445 | .I irq | |
446 | -- the hardware interrupt that the card is configured to use. | |
447 | Valid values will be dependent on the card in question, but will | |
c13182ef MK |
448 | usually be 5, 7, 9, 10, 11, 12, and 15. |
449 | The other values are usually | |
fea681da | 450 | used for common peripherals like IDE hard disks, floppies, serial |
fb3969cd | 451 | ports, and so on. |
fea681da MK |
452 | |
453 | .I scsi-id | |
454 | -- the ID that the host adapter uses to identify itself on the | |
c13182ef MK |
455 | SCSI bus. |
456 | Only some host adapters allow you to change this value, as | |
457 | most have it permanently specified internally. | |
458 | The usual default value | |
fea681da MK |
459 | is 7, but the Seagate and Future Domain TMC-950 boards use 6. |
460 | ||
461 | .I parity | |
462 | -- whether the SCSI host adapter expects the attached devices | |
c13182ef MK |
463 | to supply a parity value with all information exchanges. |
464 | Specifying a one indicates parity checking is enabled, | |
465 | and a zero disables parity checking. | |
466 | Again, not all adapters will support selection of parity | |
d9bfdb9c | 467 | behavior as a boot argument. |
bebbbd1f | 468 | .TP |
40dedbfe | 469 | .B "'max_scsi_luns=...'" |
310672d6 | 470 | A SCSI device can have a number of 'subdevices' contained within |
c13182ef MK |
471 | itself. |
472 | The most common example is one of the new SCSI CD-ROMs that | |
473 | handle more than one disk at a time. | |
474 | Each CD is addressed as a | |
25715c96 | 475 | \&'Logical Unit Number' (LUN) of that particular device. |
c13182ef | 476 | But most |
fea681da MK |
477 | devices, such as hard disks, tape drives and such are only one device, |
478 | and will be assigned to LUN zero. | |
479 | ||
480 | Some poorly designed SCSI devices cannot handle being probed for | |
c13182ef | 481 | LUNs not equal to zero. |
29aceda4 | 482 | Therefore, if the compile-time flag |
40dedbfe MK |
483 | .B CONFIG_SCSI_MULTI_LUN |
484 | is not set, newer kernels will by default only probe LUN zero. | |
fea681da MK |
485 | |
486 | To specify the number of probed LUNs at boot, one enters | |
25715c96 | 487 | \&'max_scsi_luns=n' as a boot arg, where n is a number between one and |
c13182ef MK |
488 | eight. |
489 | To avoid problems as described above, one would use n=1 to | |
fea681da | 490 | avoid upsetting such broken devices. |
bebbbd1f MK |
491 | .TP |
492 | .B "SCSI tape configuration" | |
fea681da MK |
493 | Some boot time configuration of the SCSI tape driver can be achieved |
494 | by using the following: | |
495 | .IP | |
496 | .BI st= buf_size[,write_threshold[,max_bufs]] | |
bebbbd1f | 497 | .sp |
c13182ef MK |
498 | The first two numbers are specified in units of kB. |
499 | The default | |
fea681da MK |
500 | .I buf_size |
501 | is 32kB, and the maximum size that can be specified is a | |
c13182ef MK |
502 | ridiculous 16384kB. |
503 | The | |
fea681da MK |
504 | .I write_threshold |
505 | is the value at which the buffer is committed to tape, with a | |
c13182ef MK |
506 | default value of 30kB. |
507 | The maximum number of buffers varies | |
fea681da MK |
508 | with the number of drives detected, and has a default of two. |
509 | An example usage would be: | |
510 | .IP | |
511 | st=32,30,2 | |
bebbbd1f | 512 | .IP |
4568d084 MK |
513 | Full details can be found in the file |
514 | .I Documentation/scsi/st.txt | |
515 | (or | |
516 | .I drivers/scsi/README.st | |
66a9882e | 517 | for older kernels) in the Linux kernel source. |
bebbbd1f MK |
518 | .TP |
519 | .B "Adaptec aha151x, aha152x, aic6260, aic6360, SB16-SCSI configuration" | |
fea681da MK |
520 | The aha numbers refer to cards and the aic numbers refer to the actual |
521 | SCSI chip on these type of cards, including the Soundblaster-16 SCSI. | |
522 | ||
523 | The probe code for these SCSI hosts looks for an installed BIOS, and | |
c13182ef MK |
524 | if none is present, the probe will not find your card. |
525 | Then you will | |
fea681da MK |
526 | have to use a boot arg of the form: |
527 | .IP | |
528 | .BI aha152x= iobase[,irq[,scsi-id[,reconnect[,parity]]]] | |
bebbbd1f | 529 | .IP |
fea681da MK |
530 | If the driver was compiled with debugging enabled, a sixth |
531 | value can be specified to set the debug level. | |
532 | ||
533 | All the parameters are as described at the top of this section, and the | |
534 | .I reconnect | |
c7094399 | 535 | value will allow device disconnect/reconnect if a nonzero value |
c13182ef MK |
536 | is used. |
537 | An example usage is as follows: | |
fea681da MK |
538 | .IP |
539 | aha152x=0x340,11,7,1 | |
bebbbd1f | 540 | .IP |
fea681da MK |
541 | Note that the parameters must be specified in order, meaning that if |
542 | you want to specify a parity setting, then you will have to specify an | |
543 | iobase, irq, scsi-id and reconnect value as well. | |
bebbbd1f MK |
544 | .TP |
545 | .B "Adaptec aha154x configuration" | |
fea681da | 546 | The aha1542 series cards have an i82077 floppy controller onboard, |
c13182ef MK |
547 | while the aha1540 series cards do not. |
548 | These are busmastering cards, | |
324633ae | 549 | and have parameters to set the "fairness" that is used to share |
c13182ef MK |
550 | the bus with other devices. |
551 | The boot arg looks like the following. | |
fea681da MK |
552 | .IP |
553 | .BI aha1542= iobase[,buson,busoff[,dmaspeed]] | |
bebbbd1f | 554 | .IP |
fea681da | 555 | Valid iobase values are usually one of: 0x130, 0x134, 0x230, 0x234, |
c13182ef MK |
556 | 0x330, 0x334. |
557 | Clone cards may permit other values. | |
fea681da MK |
558 | |
559 | The | |
560 | .IR buson ", " busoff | |
561 | values refer to the number of microseconds that the | |
c13182ef MK |
562 | card dominates the ISA bus. |
563 | The defaults are 11us on, and 4us off, so | |
fea681da MK |
564 | that other cards (such as an ISA LANCE Ethernet card) have a chance to |
565 | get access to the ISA bus. | |
566 | ||
567 | The | |
568 | .I dmaspeed | |
569 | value refers to the rate (in MB/s) at which the DMA | |
c13182ef MK |
570 | (Direct Memory Access) transfers proceed. |
571 | The default is 5MB/s. | |
fea681da | 572 | Newer revision cards allow you to select this value as part of the |
c13182ef MK |
573 | soft-configuration, older cards use jumpers. |
574 | You can use values up to | |
fea681da MK |
575 | 10MB/s assuming that your motherboard is capable of handling it. |
576 | Experiment with caution if using values over 5MB/s. | |
bebbbd1f MK |
577 | .TP |
578 | .B "Adaptec aha274x, aha284x, aic7xxx configuration" | |
fea681da MK |
579 | These boards can accept an argument of the form: |
580 | .IP | |
581 | .BI aic7xxx= extended,no_reset | |
bebbbd1f | 582 | .IP |
fea681da MK |
583 | The |
584 | .I extended | |
c7094399 | 585 | value, if nonzero, indicates that extended translation for large |
c13182ef MK |
586 | disks is enabled. |
587 | The | |
fea681da | 588 | .I no_reset |
c7094399 | 589 | value, if nonzero, tells the driver not to reset the SCSI bus when |
d89be9f3 | 590 | setting up the host adapter at boot. |
bebbbd1f | 591 | .TP |
40dedbfe | 592 | .B "AdvanSys SCSI Hosts configuration ('advansys=')" |
fea681da | 593 | The AdvanSys driver can accept up to four i/o addresses that will be |
c13182ef MK |
594 | probed for an AdvanSys SCSI card. |
595 | Note that these values (if used) do | |
596 | not effect EISA or PCI probing in any way. | |
597 | They are only used for | |
598 | probing ISA and VLB cards. | |
599 | In addition, if the driver has been | |
fea681da | 600 | compiled with debugging enabled, the level of debugging output can be |
c13182ef MK |
601 | set by adding an 0xdeb[0-f] parameter. |
602 | The 0-f allows setting the | |
fea681da | 603 | level of the debugging messages to any of 16 levels of verbosity. |
bebbbd1f MK |
604 | .TP |
605 | .B "AM53C974" | |
fea681da MK |
606 | .IP |
607 | .BI AM53C974= host-scsi-id,target-scsi-id,max-rate,max-offset | |
bebbbd1f | 608 | .TP |
40dedbfe | 609 | .B "BusLogic SCSI Hosts configuration ('BusLogic=')" |
fea681da MK |
610 | .IP |
611 | .BI BusLogic= N1,N2,N3,N4,N5,S1,S2,... | |
bebbbd1f | 612 | .IP |
fea681da MK |
613 | For an extensive discussion of the BusLogic command line parameters, |
614 | see | |
0daa9e92 | 615 | .I /usr/src/linux/drivers/scsi/BusLogic.c |
c13182ef MK |
616 | (lines 3149-3270 in the kernel version I am looking at). |
617 | The text | |
fea681da MK |
618 | below is a very much abbreviated extract. |
619 | ||
c13182ef MK |
620 | The parameters N1-N5 are integers. |
621 | The parameters S1,... are strings. | |
fea681da MK |
622 | N1 is the I/O Address at which the Host Adapter is located. |
623 | N2 is the Tagged Queue Depth to use for Target Devices that support | |
624 | Tagged Queuing. | |
c13182ef MK |
625 | N3 is the Bus Settle Time in seconds. |
626 | This is the amount of time | |
fea681da MK |
627 | to wait between a Host Adapter Hard Reset which |
628 | initiates a SCSI Bus Reset and issuing any SCSI Commands. | |
629 | N4 is the Local Options (for one Host Adapter). | |
630 | N5 is the Global Options (for all Host Adapters). | |
631 | ||
632 | The string options are used to provide control over Tagged Queuing | |
633 | (TQ:Default, TQ:Enable, TQ:Disable, TQ:<Per-Target-Spec>), over | |
634 | Error Recovery (ER:Default, ER:HardReset, ER:BusDeviceReset, | |
635 | ER:None, ER:<Per-Target-Spec>), and over Host Adapter Probing | |
636 | (NoProbe, NoProbeISA, NoSortPCI). | |
bebbbd1f MK |
637 | .TP |
638 | .B "EATA/DMA configuration" | |
fea681da MK |
639 | The default list of i/o ports to be probed can be changed by |
640 | .IP | |
40dedbfe | 641 | .BI eata= iobase,iobase,...\fP. |
bebbbd1f MK |
642 | .TP |
643 | .B "Future Domain TMC-16x0 configuration" | |
fea681da MK |
644 | .IP |
645 | .BI fdomain= iobase,irq[,adapter_id] | |
bebbbd1f MK |
646 | .TP |
647 | .B "Great Valley Products (GVP) SCSI controller configuration" | |
fea681da MK |
648 | .IP |
649 | .BI gvp11= dma_transfer_bitmask | |
bebbbd1f MK |
650 | .TP |
651 | .B "Future Domain TMC-8xx, TMC-950 configuration" | |
fea681da MK |
652 | .IP |
653 | .BI tmc8xx= mem_base,irq | |
bebbbd1f | 654 | .IP |
fea681da MK |
655 | The |
656 | .I mem_base | |
657 | value is the value of the memory mapped I/O region that | |
c13182ef MK |
658 | the card uses. |
659 | This will usually be one of the following values: | |
fea681da | 660 | 0xc8000, 0xca000, 0xcc000, 0xce000, 0xdc000, 0xde000. |
bebbbd1f MK |
661 | .TP |
662 | .B "IN2000 configuration" | |
fea681da MK |
663 | .IP |
664 | .BI in2000= S | |
bebbbd1f | 665 | .IP |
fea681da MK |
666 | where S is a comma-separated string of items keyword[:value]. |
667 | Recognized keywords (possibly with value) are: | |
668 | ioport:addr, noreset, nosync:x, period:ns, disconnect:x, | |
c13182ef MK |
669 | debug:x, proc:x. |
670 | For the function of these parameters, see | |
fea681da | 671 | .IR /usr/src/linux/drivers/scsi/in2000.c . |
bebbbd1f MK |
672 | .TP |
673 | .B "NCR5380 and NCR53C400 configuration" | |
fea681da MK |
674 | The boot arg is of the form |
675 | .IP | |
676 | .BI ncr5380= iobase,irq,dma | |
bebbbd1f | 677 | .IP |
fea681da MK |
678 | or |
679 | .IP | |
680 | .BI ncr53c400= iobase,irq | |
bebbbd1f | 681 | .IP |
fea681da | 682 | If the card doesn't use interrupts, then an IRQ value of 255 (0xff) will |
c13182ef MK |
683 | disable interrupts. |
684 | An IRQ value of 254 means to autoprobe. | |
4568d084 MK |
685 | More details can be found in the file |
686 | .I Documentation/scsi/g_NCR5380.txt | |
687 | (or | |
688 | .I drivers/scsi/README.g_NCR5380 | |
66a9882e | 689 | for older kernels) in the Linux kernel source. |
bebbbd1f MK |
690 | .TP |
691 | .B "NCR53C8xx configuration" | |
fea681da MK |
692 | .IP |
693 | .BI ncr53c8xx= S | |
bebbbd1f | 694 | .IP |
fea681da MK |
695 | where S is a comma-separated string of items keyword:value. |
696 | Recognized keywords are: mpar (master_parity), spar (scsi_parity), | |
697 | disc (disconnection), specf (special_features), ultra (ultra_scsi), | |
698 | fsn (force_sync_nego), tags (default_tags), sync (default_sync), | |
699 | verb (verbose), debug (debug), burst (burst_max). | |
700 | For the function of the assigned values, see | |
701 | .IR /usr/src/linux/drivers/scsi/ncr53c8xx.c . | |
bebbbd1f MK |
702 | .TP |
703 | .B "NCR53c406a configuration" | |
fea681da MK |
704 | .IP |
705 | .BI ncr53c406a= iobase[,irq[,fastpio]] | |
bebbbd1f | 706 | .IP |
24b74457 | 707 | Specify irq = 0 for noninterrupt driven mode. |
fea681da | 708 | Set fastpio = 1 for fast pio mode, 0 for slow mode. |
bebbbd1f MK |
709 | .TP |
710 | .B "Pro Audio Spectrum configuration" | |
fea681da | 711 | The PAS16 uses a NC5380 SCSI chip, and newer models support |
c13182ef MK |
712 | jumperless configuration. |
713 | The boot arg is of the form: | |
fea681da MK |
714 | .IP |
715 | .BI pas16= iobase,irq | |
bebbbd1f | 716 | .IP |
fea681da MK |
717 | The only difference is that you can specify an IRQ value of 255, which |
718 | will tell the driver to work without using interrupts, albeit at a | |
c13182ef MK |
719 | performance loss. |
720 | The iobase is usually 0x388. | |
bebbbd1f MK |
721 | .TP |
722 | .B "Seagate ST-0x configuration" | |
fea681da MK |
723 | If your card is not detected at boot time, |
724 | you will then have to use a boot arg of the form: | |
725 | .IP | |
726 | .BI st0x= mem_base,irq | |
bebbbd1f | 727 | .IP |
fea681da MK |
728 | The |
729 | .I mem_base | |
730 | value is the value of the memory mapped I/O region that | |
c13182ef MK |
731 | the card uses. |
732 | This will usually be one of the following values: | |
fea681da | 733 | 0xc8000, 0xca000, 0xcc000, 0xce000, 0xdc000, 0xde000. |
bebbbd1f MK |
734 | .TP |
735 | .B "Trantor T128 configuration" | |
fea681da MK |
736 | These cards are also based on the NCR5380 chip, and accept the |
737 | following options: | |
738 | .IP | |
739 | .BI t128= mem_base,irq | |
bebbbd1f | 740 | .IP |
fea681da MK |
741 | The valid values for |
742 | .I mem_base | |
743 | are as follows: 0xcc000, 0xc8000, 0xdc000, 0xd8000. | |
bebbbd1f MK |
744 | .TP |
745 | .B "UltraStor 14F/34F configuration" | |
fea681da MK |
746 | The default list of i/o ports to be probed can be changed by |
747 | .IP | |
748 | .BI eata= iobase,iobase,... . | |
bebbbd1f MK |
749 | .TP |
750 | .B "WD7000 configuration" | |
fea681da MK |
751 | .IP |
752 | .BI wd7000= irq,dma,iobase | |
bebbbd1f MK |
753 | .TP |
754 | .B "Commodore Amiga A2091/590 SCSI controller configuration" | |
fea681da MK |
755 | .IP |
756 | .BI wd33c93= S | |
bebbbd1f | 757 | .IP |
c13182ef MK |
758 | where S is a comma-separated string of options. |
759 | Recognized options are | |
fea681da | 760 | nosync:bitmask, nodma:x, period:ns, disconnect:x, debug:x, |
c13182ef MK |
761 | clock:x, next. |
762 | For details, see | |
fea681da | 763 | .IR /usr/src/linux/drivers/scsi/wd33c93.c . |
73d8cece | 764 | .SS Hard disks |
bebbbd1f MK |
765 | .TP |
766 | .B "IDE Disk/CD-ROM Driver Parameters" | |
fea681da | 767 | The IDE driver accepts a number of parameters, which range from disk |
c13182ef | 768 | geometry specifications, to support for broken controller chips. |
e2badfdf | 769 | Drive-specific options are specified by using 'hdX=' with X in 'a'-'h'. |
fea681da | 770 | |
e2badfdf MK |
771 | Non-drive-specific options are specified with the prefix 'hd='. |
772 | Note that using a drive-specific prefix for a non-drive-specific option | |
fea681da MK |
773 | will still work, and the option will just be applied as expected. |
774 | ||
40dedbfe | 775 | Also note that 'hd=' can be used to refer to the next unspecified |
c13182ef MK |
776 | drive in the (a, ..., h) sequence. |
777 | For the following discussions, | |
40dedbfe | 778 | the 'hd=' option will be cited for brevity. |
c13182ef | 779 | See the file |
4568d084 MK |
780 | .I Documentation/ide.txt |
781 | (or | |
782 | .I drivers/block/README.ide | |
66a9882e | 783 | for older kernels) in the Linux kernel source for more details. |
bebbbd1f | 784 | .TP |
40dedbfe | 785 | .B "The 'hd=cyls,heads,sects[,wpcom[,irq]]' options" |
fea681da | 786 | These options are used to specify the physical geometry of the disk. |
c13182ef MK |
787 | Only the first three values are required. |
788 | The cylinder/head/sectors | |
789 | values will be those used by fdisk. | |
790 | The write precompensation value | |
791 | is ignored for IDE disks. | |
792 | The IRQ value specified will be the IRQ | |
fea681da | 793 | used for the interface that the drive resides on, and is not really a |
e2badfdf | 794 | drive-specific parameter. |
bebbbd1f | 795 | .TP |
40dedbfe | 796 | .B "The 'hd=serialize' option" |
fea681da MK |
797 | The dual IDE interface CMD-640 chip is broken as designed such that |
798 | when drives on the secondary interface are used at the same time as | |
c13182ef MK |
799 | drives on the primary interface, it will corrupt your data. |
800 | Using this | |
fea681da MK |
801 | option tells the driver to make sure that both interfaces are never |
802 | used at the same time. | |
bebbbd1f | 803 | .TP |
40dedbfe | 804 | .B "The 'hd=dtc2278' option" |
fea681da | 805 | This option tells the driver that you have a DTC-2278D IDE interface. |
e2badfdf | 806 | The driver then tries to do DTC-specific operations to enable the |
fea681da | 807 | second interface and to enable faster transfer modes. |
bebbbd1f | 808 | .TP |
40dedbfe | 809 | .B "The 'hd=noprobe' option" |
c13182ef MK |
810 | Do not probe for this drive. |
811 | For example, | |
fea681da MK |
812 | .IP |
813 | hdb=noprobe hdb=1166,7,17 | |
bebbbd1f | 814 | .IP |
fea681da MK |
815 | would disable the probe, but still specify the drive geometry so |
816 | that it would be registered as a valid block device, and hence | |
817 | usable. | |
bebbbd1f | 818 | .TP |
40dedbfe MK |
819 | .B "The 'hd=nowerr' option" |
820 | Some drives apparently have the | |
821 | .B WRERR_STAT | |
822 | bit stuck on permanently. | |
fea681da | 823 | This enables a work-around for these broken devices. |
bebbbd1f | 824 | .TP |
40dedbfe | 825 | .B "The 'hd=cdrom' option" |
fea681da | 826 | This tells the IDE driver that there is an ATAPI compatible CD-ROM |
c13182ef MK |
827 | attached in place of a normal IDE hard disk. |
828 | In most cases the CD-ROM | |
fea681da | 829 | is identified automatically, but if it isn't then this may help. |
bebbbd1f | 830 | .TP |
40dedbfe | 831 | .B "Standard ST-506 Disk Driver Options ('hd=')" |
fea681da | 832 | The standard disk driver can accept geometry arguments for the disks |
c13182ef MK |
833 | similar to the IDE driver. |
834 | Note however that it only expects three | |
835 | values (C/H/S); any more or any less and it will silently ignore you. | |
40dedbfe | 836 | Also, it only accepts 'hd=' as an argument, that is, 'hda=' |
c13182ef MK |
837 | and so on are not valid here. |
838 | The format is as follows: | |
fea681da MK |
839 | .IP |
840 | hd=cyls,heads,sects | |
bebbbd1f | 841 | .IP |
fea681da MK |
842 | If there are two disks installed, the above is repeated with the |
843 | geometry parameters of the second disk. | |
bebbbd1f | 844 | .TP |
40dedbfe | 845 | .B "XT Disk Driver Options ('xd=')" |
fea681da MK |
846 | If you are unfortunate enough to be using one of these old 8 bit cards |
847 | that move data at a whopping 125kB/s then here is the scoop. | |
d9bfdb9c | 848 | If the card is not recognized, you will have to use a boot arg of the form: |
fea681da MK |
849 | .IP |
850 | xd=type,irq,iobase,dma_chan | |
bebbbd1f | 851 | .IP |
fea681da | 852 | The type value specifies the particular manufacturer of the card, |
c13182ef MK |
853 | overriding autodetection. |
854 | For the types to use, consult the | |
fea681da | 855 | .I drivers/block/xd.c |
c13182ef MK |
856 | source file of the kernel you are using. |
857 | The type is an index in the list | |
fea681da MK |
858 | .I xd_sigs |
859 | and in the course of time | |
860 | .\" 1.1.50, 1.3.81, 1.3.99, 2.0.34, 2.1.67, 2.1.78, 2.1.127 | |
861 | types have been added to or deleted from the middle of the list, | |
c13182ef MK |
862 | changing all type numbers. |
863 | Today (Linux 2.5.0) the types are | |
fea681da MK |
864 | 0=generic; 1=DTC 5150cx; 2,3=DTC 5150x; 4,5=Western Digital; |
865 | 6,7,8=Seagate; 9=Omti; 10=XEBEC, and where here several types are | |
866 | given with the same designation, they are equivalent. | |
867 | ||
868 | The xd_setup() function does no checking on the values, and assumes | |
c13182ef MK |
869 | that you entered all four values. |
870 | Don't disappoint it. | |
871 | Here is an | |
fea681da | 872 | example usage for a WD1002 controller with the BIOS disabled/removed, |
40dedbfe | 873 | using the 'default' XT controller parameters: |
fea681da MK |
874 | .IP |
875 | xd=2,5,0x320,3 | |
bebbbd1f MK |
876 | .TP |
877 | .B "Syquest's EZ* removable disks" | |
fea681da MK |
878 | .IP |
879 | .BI ez= iobase[,irq[,rep[,nybble]]] | |
73d8cece | 880 | .SS IBM MCA bus devices |
fea681da MK |
881 | See also |
882 | .IR /usr/src/linux/Documentation/mca.txt . | |
bebbbd1f MK |
883 | .TP |
884 | .B "PS/2 ESDI hard disks" | |
fea681da MK |
885 | It is possible to specify the desired geometry at boot time: |
886 | .IP | |
887 | .BI ed= cyls,heads,sectors. | |
bebbbd1f | 888 | .IP |
fea681da MK |
889 | For a ThinkPad-720, add the option |
890 | .IP | |
891 | .BR tp720=1 . | |
bebbbd1f MK |
892 | .TP |
893 | .B "IBM Microchannel SCSI Subsystem configuration" | |
fea681da MK |
894 | .IP |
895 | .BI ibmmcascsi= N | |
bebbbd1f | 896 | .IP |
fea681da | 897 | where N is the \fIpun\fP (SCSI ID) of the subsystem. |
bebbbd1f MK |
898 | .TP |
899 | .B "The Aztech Interface" | |
fea681da MK |
900 | The syntax for this type of card is: |
901 | .IP | |
902 | aztcd=iobase[,magic_number] | |
bebbbd1f | 903 | .IP |
fea681da | 904 | If you set the magic_number to 0x79 then the driver will try and run |
c13182ef MK |
905 | anyway in the event of an unknown firmware version. |
906 | All other values | |
fea681da | 907 | are ignored. |
bebbbd1f MK |
908 | .TP |
909 | .B "Parallel port CD-ROM drives" | |
fea681da MK |
910 | Syntax: |
911 | .IP | |
912 | pcd.driveN=prt,pro,uni,mod,slv,dly | |
913 | .br | |
914 | pcd.nice=nice | |
bebbbd1f | 915 | .IP |
40dedbfe MK |
916 | where 'port' is the base address, 'pro' is the protocol number, 'uni' |
917 | is the unit selector (for chained devices), 'mod' is the mode (or \-1 | |
918 | to choose the best automatically), 'slv' is 1 if it should be a slave, | |
919 | and 'dly' is a small integer for slowing down port accesses. | |
920 | The 'nice' parameter controls the driver's use of idle CPU time, at the | |
fea681da | 921 | expense of some speed. |
bebbbd1f MK |
922 | .TP |
923 | .B "The CDU-31A and CDU-33A Sony Interface" | |
fea681da | 924 | This CD-ROM interface is found on some of the Pro Audio Spectrum sound |
c13182ef MK |
925 | cards, and other Sony supplied interface cards. |
926 | The syntax is as follows: | |
fea681da MK |
927 | .IP |
928 | cdu31a=iobase,[irq[,is_pas_card]] | |
bebbbd1f | 929 | .IP |
fea681da | 930 | Specifying an IRQ value of zero tells the driver that hardware |
c13182ef MK |
931 | interrupts aren't supported (as on some PAS cards). |
932 | If your card | |
fea681da MK |
933 | supports interrupts, you should use them as it cuts down on the CPU |
934 | usage of the driver. | |
935 | ||
936 | The | |
937 | .I is_pas_card | |
40dedbfe | 938 | should be entered as 'PAS' if using a Pro Audio Spectrum card, |
fea681da | 939 | and otherwise it should not be specified at all. |
bebbbd1f MK |
940 | .TP |
941 | .B "The CDU-535 Sony Interface" | |
fea681da MK |
942 | The syntax for this CD-ROM interface is: |
943 | .IP | |
944 | sonycd535=iobase[,irq] | |
bebbbd1f | 945 | .IP |
40dedbfe | 946 | A zero can be used for the I/O base as a 'placeholder' if one wishes |
fea681da | 947 | to specify an IRQ value. |
bebbbd1f MK |
948 | .TP |
949 | .B "The GoldStar Interface" | |
fea681da MK |
950 | The syntax for this CD-ROM interface is: |
951 | .IP | |
952 | gscd=iobase | |
bebbbd1f MK |
953 | .TP |
954 | .B "The ISP16 CD-ROM Interface" | |
fea681da MK |
955 | Syntax: |
956 | .IP | |
957 | isp16=[iobase[,irq[,dma[,type]]]] | |
bebbbd1f | 958 | .IP |
c13182ef | 959 | (three integers and a string). |
40dedbfe | 960 | If the type is given as 'noisp16', |
c13182ef MK |
961 | the interface will not be configured. |
962 | Other recognized types | |
40dedbfe | 963 | are: 'Sanyo", 'Sony', 'Panasonic' and 'Mitsumi'. |
bebbbd1f MK |
964 | .TP |
965 | .B "The Mitsumi Standard Interface" | |
fea681da MK |
966 | The syntax for this CD-ROM interface is: |
967 | .IP | |
968 | mcd=iobase,[irq[,wait_value]] | |
bebbbd1f | 969 | .IP |
fea681da MK |
970 | The |
971 | .I wait_value | |
972 | is used as an internal timeout value for people who are | |
973 | having problems with their drive, and may or may not be implemented | |
29aceda4 | 974 | depending on a compile-time #define. |
fea681da MK |
975 | The Mitsumi FX400 is an IDE/ATAPI CD-ROM player and does not use |
976 | the mcd driver. | |
bebbbd1f MK |
977 | .TP |
978 | .B "The Mitsumi XA/MultiSession Interface" | |
fea681da MK |
979 | This is for the same hardware as above, but the driver has extended features. |
980 | Syntax: | |
981 | .IP | |
982 | mcdx=iobase[,irq] | |
bebbbd1f MK |
983 | .TP |
984 | .B "The Optics Storage Interface" | |
fea681da MK |
985 | The syntax for this type of card is: |
986 | .IP | |
987 | optcd=iobase | |
bebbbd1f MK |
988 | .TP |
989 | .B "The Phillips CM206 Interface" | |
fea681da MK |
990 | The syntax for this type of card is: |
991 | .IP | |
992 | cm206=[iobase][,irq] | |
bebbbd1f | 993 | .IP |
fea681da MK |
994 | The driver assumes numbers between 3 and 11 are IRQ values, and |
995 | numbers between 0x300 and 0x370 are I/O ports, so you can specify one, | |
c13182ef | 996 | or both numbers, in any order. |
40dedbfe | 997 | It also accepts 'cm206=auto' to enable |
fea681da | 998 | autoprobing. |
bebbbd1f MK |
999 | .TP |
1000 | .B "The Sanyo Interface" | |
fea681da MK |
1001 | The syntax for this type of card is: |
1002 | .IP | |
1003 | sjcd=iobase[,irq[,dma_channel]] | |
bebbbd1f MK |
1004 | .TP |
1005 | .B "The SoundBlaster Pro Interface" | |
fea681da MK |
1006 | The syntax for this type of card is: |
1007 | .IP | |
1008 | sbpcd=iobase,type | |
bebbbd1f | 1009 | .IP |
fea681da | 1010 | where type is one of the following (case sensitive) strings: |
25715c96 | 1011 | \&'SoundBlaster', 'LaserMate', or 'SPEA'. |
c13182ef | 1012 | The I/O base is that of the |
fea681da | 1013 | CD-ROM interface, and not that of the sound portion of the card. |
73d8cece | 1014 | .SS Ethernet devices |
fea681da | 1015 | Different drivers make use of different parameters, but they all at |
c13182ef MK |
1016 | least share having an IRQ, an I/O port base value, and a name. |
1017 | In its most generic form, it looks something like this: | |
fea681da MK |
1018 | .IP |
1019 | ether=irq,iobase[,param_1[,...param_8]],name | |
bebbbd1f | 1020 | .IP |
80c9146c | 1021 | The first nonnumeric argument is taken as the name. |
c13182ef MK |
1022 | The param_n values (if applicable) usually have different meanings for each |
1023 | different card/driver. | |
1024 | Typical param_n values are used to specify | |
fea681da MK |
1025 | things like shared memory address, interface selection, DMA channel |
1026 | and the like. | |
1027 | ||
1028 | The most common use of this parameter is to force probing for a second | |
c13182ef MK |
1029 | ethercard, as the default is to only probe for one. |
1030 | This can be accomplished with a simple: | |
fea681da MK |
1031 | .IP |
1032 | ether=0,0,eth1 | |
bebbbd1f | 1033 | .IP |
fea681da MK |
1034 | Note that the values of zero for the IRQ and I/O base in the above |
1035 | example tell the driver(s) to autoprobe. | |
1036 | ||
1037 | The Ethernet-HowTo has extensive documentation on using multiple | |
e2badfdf | 1038 | cards and on the card/driver-specific implementation |
c13182ef MK |
1039 | of the param_n values where used. |
1040 | Interested readers should refer to | |
fea681da | 1041 | the section in that document on their particular card. |
73d8cece | 1042 | .SS The floppy disk driver |
fea681da | 1043 | There are many floppy driver options, and they are all listed in |
4568d084 MK |
1044 | .I Documentation/floppy.txt |
1045 | (or | |
1046 | .I drivers/block/README.fd | |
66a9882e | 1047 | for older kernels) in the Linux kernel source. |
c13182ef | 1048 | This information is taken directly |
fea681da | 1049 | from that file. |
bebbbd1f MK |
1050 | .TP |
1051 | .B "floppy=mask,allowed_drive_mask" | |
10f5f294 | 1052 | Sets the bit mask of allowed drives to mask. |
c13182ef MK |
1053 | By default, only units 0 |
1054 | and 1 of each floppy controller are allowed. | |
1055 | This is done because | |
c8f2dd47 | 1056 | certain nonstandard hardware (ASUS PCI motherboards) mess up the |
c13182ef MK |
1057 | keyboard when accessing units 2 or 3. |
1058 | This option is somewhat | |
fea681da | 1059 | obsoleted by the cmos option. |
bebbbd1f MK |
1060 | .TP |
1061 | .B "floppy=all_drives" | |
10f5f294 | 1062 | Sets the bit mask of allowed drives to all drives. |
c13182ef | 1063 | Use this if you have |
fea681da | 1064 | more than two drives connected to a floppy controller. |
bebbbd1f MK |
1065 | .TP |
1066 | .B "floppy=asus_pci" | |
6387216b MK |
1067 | Sets the bit mask to allow only units 0 and 1. |
1068 | (The default) | |
bebbbd1f MK |
1069 | .TP |
1070 | .B "floppy=daring" | |
fea681da | 1071 | Tells the floppy driver that you have a well behaved floppy |
c13182ef MK |
1072 | controller. |
1073 | This allows more efficient and smoother operation, but | |
1074 | may fail on certain controllers. | |
1075 | This may speed up certain operations. | |
bebbbd1f MK |
1076 | .TP |
1077 | .B "floppy=0,daring" | |
fea681da MK |
1078 | Tells the floppy driver that your floppy controller should be used |
1079 | with caution. | |
bebbbd1f MK |
1080 | .TP |
1081 | .B "floppy=one_fdc" | |
fea681da | 1082 | Tells the floppy driver that you have only floppy controller (default) |
bebbbd1f | 1083 | .TP |
40dedbfe | 1084 | .BR floppy=two_fdc " or " floppy=address,two_fdc |
c13182ef MK |
1085 | Tells the floppy driver that you have two floppy controllers. |
1086 | The second floppy controller is assumed to be at address. | |
1087 | If address is | |
fea681da | 1088 | not given, 0x370 is assumed. |
bebbbd1f MK |
1089 | .TP |
1090 | .B "floppy=thinkpad" | |
c13182ef MK |
1091 | Tells the floppy driver that you have a Thinkpad. |
1092 | Thinkpads use an | |
fea681da | 1093 | inverted convention for the disk change line. |
bebbbd1f MK |
1094 | .TP |
1095 | .B "floppy=0,thinkpad" | |
fea681da | 1096 | Tells the floppy driver that you don't have a Thinkpad. |
bebbbd1f MK |
1097 | .TP |
1098 | .B "floppy=drive,type,cmos" | |
c13182ef MK |
1099 | Sets the cmos type of drive to type. |
1100 | Additionally, this drive is | |
10f5f294 | 1101 | allowed in the bit mask. |
c13182ef | 1102 | This is useful if you have more than two |
fea681da | 1103 | floppy drives (only two can be described in the physical cmos), or if |
c8f2dd47 | 1104 | your BIOS uses nonstandard CMOS types. |
c13182ef | 1105 | Setting the CMOS to 0 for the |
fea681da MK |
1106 | first two drives (default) makes the floppy driver read the physical |
1107 | cmos for those drives. | |
bebbbd1f MK |
1108 | .TP |
1109 | .B "floppy=unexpected_interrupts" | |
fea681da | 1110 | Print a warning message when an unexpected interrupt is received |
d9bfdb9c | 1111 | (default behavior) |
bebbbd1f | 1112 | .TP |
40dedbfe | 1113 | .BR floppy=no_unexpected_interrupts " or " floppy=L40SX |
c13182ef MK |
1114 | Don't print a message when an unexpected interrupt is received. |
1115 | This is needed on IBM L40SX laptops in certain video modes. | |
1116 | (There seems to | |
1117 | be an interaction between video and floppy. | |
1118 | The unexpected interrupts | |
fea681da | 1119 | only affect performance, and can safely be ignored.) |
73d8cece | 1120 | .SS The sound driver |
fea681da | 1121 | The sound driver can also accept boot args to override the compiled in |
c13182ef MK |
1122 | values. |
1123 | This is not recommended, as it is rather complex. | |
66a9882e | 1124 | It is described in the Linux kernel source file |
ef505ff0 MK |
1125 | .IR Documentation/sound/oss/README.OSS |
1126 | .RI ( drivers/sound/Readme.linux | |
1127 | in older kernel versions). | |
c13182ef | 1128 | It accepts |
fea681da MK |
1129 | a boot arg of the form: |
1130 | .IP | |
1131 | sound=device1[,device2[,device3...[,device10]]] | |
bebbbd1f | 1132 | .IP |
fea681da MK |
1133 | where each deviceN value is of the following format 0xTaaaId and the |
1134 | bytes are used as follows: | |
1135 | ||
4d9b6984 | 1136 | T \- device type: 1=FM, 2=SB, 3=PAS, 4=GUS, 5=MPU401, 6=SB16, |
fea681da MK |
1137 | 7=SB16-MPU401 |
1138 | ||
4d9b6984 | 1139 | aaa \- I/O address in hex. |
fea681da | 1140 | |
4d9b6984 | 1141 | I \- interrupt line in hex (i.e 10=a, 11=b, ...) |
fea681da | 1142 | |
4d9b6984 | 1143 | d \- DMA channel. |
fea681da MK |
1144 | |
1145 | As you can see it gets pretty messy, and you are better off to compile | |
c13182ef MK |
1146 | in your own personal values as recommended. |
1147 | Using a boot arg of | |
25715c96 | 1148 | \&'sound=0' will disable the sound driver entirely. |
73d8cece | 1149 | .SS ISDN drivers |
bebbbd1f MK |
1150 | .TP |
1151 | .B "The ICN ISDN driver" | |
fea681da MK |
1152 | Syntax: |
1153 | .IP | |
1154 | icn=iobase,membase,icn_id1,icn_id2 | |
bebbbd1f | 1155 | .IP |
fea681da MK |
1156 | where icn_id1,icn_id2 are two strings used to identify the |
1157 | card in kernel messages. | |
bebbbd1f MK |
1158 | .TP |
1159 | .B "The PCBIT ISDN driver" | |
fea681da MK |
1160 | Syntax: |
1161 | .IP | |
1162 | pcbit=membase1,irq1[,membase2,irq2] | |
bebbbd1f | 1163 | .IP |
fea681da | 1164 | where membaseN is the shared memory base of the N'th card, and irqN is |
c13182ef MK |
1165 | the interrupt setting of the N'th card. |
1166 | The default is IRQ 5 and | |
fea681da | 1167 | membase 0xD0000. |
bebbbd1f MK |
1168 | .TP |
1169 | .B "The Teles ISDN driver" | |
fea681da MK |
1170 | Syntax: |
1171 | .IP | |
1172 | teles=iobase,irq,membase,protocol,teles_id | |
bebbbd1f | 1173 | .IP |
fea681da MK |
1174 | where iobase is the i/o port address of the card, membase is the |
1175 | shared memory base address of the card, irq is the interrupt channel | |
1176 | the card uses, and teles_id is the unique ASCII string identifier. | |
73d8cece | 1177 | .SS Serial port drivers |
bebbbd1f | 1178 | .TP |
40dedbfe | 1179 | .B "The RISCom/8 Multiport Serial Driver ('riscom8=')" |
fea681da MK |
1180 | Syntax: |
1181 | .IP | |
1182 | riscom=iobase1[,iobase2[,iobase3[,iobase4]]] | |
bebbbd1f | 1183 | .IP |
fea681da MK |
1184 | More details can be found in |
1185 | .IR /usr/src/linux/Documentation/riscom8.txt . | |
bebbbd1f | 1186 | .TP |
40dedbfe | 1187 | .B "The DigiBoard Driver ('digi=')" |
fea681da MK |
1188 | If this option is used, it should have precisely six parameters. |
1189 | Syntax: | |
1190 | .IP | |
1191 | digi=status,type,altpin,numports,iobase,membase | |
bebbbd1f | 1192 | .IP |
fea681da MK |
1193 | The parameters maybe given as integers, or as strings. |
1194 | If strings are used, then iobase and membase should be given | |
1195 | in hexadecimal. | |
1196 | The integer arguments (fewer may be given) are in order: | |
1197 | status (Enable(1) or Disable(0) this card), | |
1198 | type (PC/Xi(0), PC/Xe(1), PC/Xeve(2), PC/Xem(3)), | |
1199 | altpin (Enable(1) or Disable(0) alternate pin arrangement), | |
1200 | numports (number of ports on this card), | |
1201 | iobase (I/O Port where card is configured (in HEX)), | |
1202 | membase (base of memory window (in HEX)). | |
1203 | Thus, the following two boot prompt arguments are equivalent: | |
1204 | .IP | |
1205 | digi=E,PC/Xi,D,16,200,D0000 | |
1206 | .br | |
1207 | digi=1,0,0,16,0x200,851968 | |
bebbbd1f | 1208 | .IP |
fea681da MK |
1209 | More details can be found in |
1210 | .IR /usr/src/linux/Documentation/digiboard.txt . | |
bebbbd1f MK |
1211 | .TP |
1212 | .B "The Baycom Serial/Parallel Radio Modem" | |
fea681da MK |
1213 | Syntax: |
1214 | .IP | |
1215 | baycom=iobase,irq,modem | |
bebbbd1f | 1216 | .IP |
fea681da | 1217 | There are precisely 3 parameters; for several cards, give |
40dedbfe | 1218 | several 'baycom=' commands. |
c13182ef | 1219 | The modem parameter is a string |
fea681da MK |
1220 | that can take one of the values ser12, ser12*, par96, par96*. |
1221 | Here the * denotes that software DCD is to be used, and | |
1222 | ser12/par96 chooses between the supported modem types. | |
4568d084 MK |
1223 | For more details, see the file |
1224 | .I Documentation/networking/baycom.txt | |
1225 | (or | |
1226 | .I drivers/net/README.baycom | |
66a9882e | 1227 | for older kernels) in the Linux kernel source. |
bebbbd1f MK |
1228 | .TP |
1229 | .B "Soundcard radio modem driver" | |
fea681da MK |
1230 | Syntax: |
1231 | .IP | |
1232 | soundmodem=iobase,irq,dma[,dma2[,serio[,pario]]],0,mode | |
bebbbd1f | 1233 | .IP |
fea681da MK |
1234 | All parameters except the last are integers; |
1235 | the dummy 0 is required because of a bug in the setup code. | |
1236 | The mode parameter is a string with syntax hw:modem, | |
1237 | where hw is one of sbc, wss, wssfdx and modem is one of | |
1238 | afsk1200, fsk9600. | |
73d8cece | 1239 | .SS The line printer driver |
bebbbd1f | 1240 | .TP |
40dedbfe | 1241 | .B "'lp='" |
fea681da MK |
1242 | Syntax: |
1243 | .IP | |
1244 | lp=0 | |
1245 | .br | |
1246 | lp=auto | |
1247 | .br | |
1248 | lp=reset | |
1249 | .br | |
1250 | lp=port[,port...] | |
bebbbd1f | 1251 | .IP |
fea681da | 1252 | You can tell the printer driver what ports to use and what ports not |
c13182ef MK |
1253 | to use. |
1254 | The latter comes in handy if you don't want the printer driver | |
fea681da | 1255 | to claim all available parallel ports, so that other drivers |
75b94dc3 | 1256 | (e.g., PLIP, PPA) can use them instead. |
fea681da | 1257 | |
c13182ef MK |
1258 | The format of the argument is multiple port names. |
1259 | For example, | |
fea681da | 1260 | lp=none,parport0 would use the first parallel port for lp1, and |
c13182ef MK |
1261 | disable lp0. |
1262 | To disable the printer driver entirely, one can use | |
fea681da | 1263 | lp=0. |
bebbbd1f MK |
1264 | .TP |
1265 | .B "WDT500/501 driver" | |
fea681da MK |
1266 | Syntax: |
1267 | .IP | |
1268 | wdt=io,irq | |
73d8cece | 1269 | .SS Mouse drivers |
bebbbd1f | 1270 | .TP |
40dedbfe | 1271 | .B "'bmouse=irq'" |
fea681da MK |
1272 | The busmouse driver only accepts one parameter, that being the |
1273 | hardware IRQ value to be used. | |
bebbbd1f | 1274 | .TP |
40dedbfe | 1275 | .B "'msmouse=irq'" |
fea681da | 1276 | And precisely the same is true for the msmouse driver. |
bebbbd1f MK |
1277 | .TP |
1278 | .B "ATARI mouse setup" | |
1279 | .IP | |
fea681da MK |
1280 | atamouse=threshold[,y-threshold] |
1281 | .IP | |
1282 | If only one argument is given, it is used for both | |
c13182ef MK |
1283 | x-threshold and y-threshold. |
1284 | Otherwise, the first argument | |
fea681da MK |
1285 | is the x-threshold, and the second the y-threshold. |
1286 | These values must lie between 1 and 20 (inclusive); the default is 2. | |
73d8cece | 1287 | .SS Video hardware |
bebbbd1f | 1288 | .TP |
40dedbfe | 1289 | .B "'no-scroll'" |
fea681da MK |
1290 | This option tells the console driver not to use hardware scroll |
1291 | (where a scroll is effected by moving the screen origin in video | |
c13182ef MK |
1292 | memory, instead of moving the data). |
1293 | It is required by certain | |
fea681da | 1294 | Braille machines. |
fd7f0a7f MK |
1295 | .\" .SH AUTHORS |
1296 | .\" Linus Torvalds (and many others) | |
47297adb | 1297 | .SH SEE ALSO |
fea681da MK |
1298 | .BR lilo.conf (5), |
1299 | .BR klogd (8), | |
1300 | .BR lilo (8), | |
1301 | .BR mount (8), | |
1302 | .BR rdev (8) | |
1303 | ||
1304 | Large parts of this man page have been derived from the | |
1305 | Boot Parameter HOWTO (version 1.0.1) written by Paul Gortmaker. | |
1306 | More information may be found in this (or a more recent) HOWTO. | |
b9560046 | 1307 | An up-to-date source of information is |
fea681da | 1308 | .IR /usr/src/linux/Documentation/kernel-parameters.txt . |