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Linux Cross Reference
Linux/Documentation/Configure.help

Version: ~ [ 2.4.0 ] ~
Architecture: ~ [ i386 ] ~ [ alpha ] ~ [ m68k ] ~ [ mips ] ~ [ ppc ] ~ [ sparc ] ~ [ sparc64 ] ~

  1 # Maintained by Axel Boldt (axel@uni-paderborn.de)
  2 #
  3 # This version of the Linux kernel configuration help texts
  4 # corresponds to the kernel versions 2.3.x.
  5 #
  6 # Translations of this file available on the WWW:
  7 #
  8 #   - Japanese, maintained by the JF Project (JF@linux.or.jp), at
  9 #     http://www.linux.or.jp/JF/JFdocs/Configure.help/
 10 #   - Russian, by kaf@linux.nevod.perm.su, at
 11 #     http://nevod.perm.su/service/linux/doc/kernel/Configure.help
 12 #   - French, by Pierre Tane (tanep@bigfoot.com), at
 13 #     http://www.traduc.org/kernelfr
 14 #   - Spanish, by Carlos Perelló Marín (fperllo@ehome.encis.es), at
 15 #     http://visar.csustan.edu/~carlos/
 16 #   - Italian, by Alessandro Rubini (rubini@linux.it), at
 17 #     ftp://ftp-pavia1.linux.it/pub/linux/Configure.help
 18 #   - Polish, by Cezar Cichocki (cezar@cs.net.pl), at
 19 #     http://www.cs.net.pl/~cezar/Kernel
 20 #   - German, by SuSE, at http://www.suse.de/~ke/kernel . This patch
 21 #     also includes infrastructure to support different languages.
 22 #
 23 # To access a document on the WWW, you need to have a direct Internet
 24 # connection and a browser program such as netscape or lynx. If you
 25 # only have email access, you can still use FTP and WWW servers: send
 26 # an email to mail-server@rtfm.mit.edu with the text 
 27 #   send usenet/news.answers/internet-services/access-via-email 
 28 # in the body of the message.
 29 #
 30 # Information about what a kernel is, what it does, how to patch and
 31 # compile it and much more is contained in the Kernel-HOWTO, available
 32 # at http://www.linuxdoc.org/docs.html#howto . Before you start
 33 # compiling, make sure that you have the necessary versions of all
 34 # programs and libraries required to compile and run this kernel; they
 35 # are listed in the file Documentation/Changes. Make sure to read the
 36 # toplevel kernel README file as well.
 37 #
 38 # Format of this file: description<nl>variable<nl>help text<nl><nl>. If
 39 # the question being documented is of type "choice", we list only the
 40 # first occurring config variable. The help texts may contain empty
 41 # lines, but every non-empty line must be indented two positions.
 42 # Order of the help texts does not matter, however, no variable should
 43 # be documented twice: if it is, only the first occurrence will be
 44 # used by Configure. We try to keep the help texts of related variables
 45 # close together. Lines starting with `#' are ignored. To be nice to
 46 # menuconfig, limit your line length to 70 characters. Use emacs'
 47 # kfill.el to edit and ispell.el to spell check this file or you lose.
 48 #
 49 # If you add a help text to this file, please try to be as gentle as
 50 # possible. Don't use unexplained acronyms and generally write for the
 51 # hypothetical ignorant but intelligent user who has just bought a PC,
 52 # removed Windows, installed Linux and is now recompiling the kernel
 53 # for the first time. Tell them what to do if they're unsure. Technical 
 54 # information should go in a README in the Documentation directory.
 55 # Mention all the relevant READMEs and HOWTOs in the help text.
 56 # Repetitions are fine since the help texts are not meant to be read
 57 # in sequence.
 58 #
 59 # All this was shamelessly stolen from several different sources. Many
 60 # thanks to all the contributors. Feel free to use these help texts in
 61 # your own kernel configuration tools. The texts are copyrighted (c)
 62 # 1995-2000 by Axel Boldt and many others and are governed by the GNU
 63 # General Public License.
 64 
 65 Prompt for development and/or incomplete code/drivers
 66 CONFIG_EXPERIMENTAL
 67   Some of the various things that Linux supports (such as network 
 68   drivers, file systems, network protocols, etc.) can be in a state 
 69   of development where the functionality, stability, or the level of 
 70   testing is not yet high enough for general use. This is usually
 71   known as the "alpha-test" phase amongst developers. If a feature is
 72   currently in alpha-test, then the developers usually discourage 
 73   uninformed widespread use of this feature by the general public to
 74   avoid "Why doesn't this work?" type mail messages. However, active
 75   testing and use of these systems is welcomed. Just be aware that it
 76   may not meet the normal level of reliability or it may fail to work
 77   in some special cases. Detailed bug reports from people familiar
 78   with the kernel internals are usually welcomed by the developers
 79   (before submitting bug reports, please read the documents README,
 80   MAINTAINERS, REPORTING-BUGS, Documentation/BUG-HUNTING, and
 81   Documentation/oops-tracing.txt in the kernel source). 
 82 
 83   This option will also make obsoleted drivers available. These are
 84   drivers that have been replaced by something else, and/or are
 85   scheduled to be removed in a future kernel release.
 86 
 87   Unless you intend to help test and develop a feature or driver that
 88   falls into this category, or you have a situation that requires
 89   using these features, you should probably say N here, which will
 90   cause this configure script to present you with fewer choices. If
 91   you say Y here, you will be offered the choice of using features or
 92   drivers that are currently considered to be in the alpha-test phase.
 93 
 94 Symmetric Multi Processing
 95 CONFIG_SMP
 96   This enables support for systems with more than one CPU. If you have
 97   a system with only one CPU, like most personal computers, say N. If
 98   you have a system with more than one CPU, say Y.
 99 
100   If you say N here, the kernel will run on single and multiprocessor
101   machines, but will use only one CPU of a multiprocessor machine. If
102   you say Y here, the kernel will run on many, but not all,
103   singleprocessor machines. On a singleprocessor machine, the kernel
104   will run faster if you say N here.
105 
106   Note that if you say Y here and choose architecture "586" or
107   "Pentium" under "Processor family", the kernel will not work on 486
108   architectures. Similarly, multiprocessor kernels for the "PPro"
109   architecture may not work on all Pentium based boards.
110 
111   People using multiprocessor machines who say Y here should also say
112   Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
113   Management" code will be disabled if you say Y here.
114 
115   See also the files Documentation/smp.tex, Documentation/smp.txt,
116   Documentation/i386/IO-APIC.txt, Documentation/nmi_watchdog.txt and the 
117   SMP-FAQ on the WWW at http://www.irisa.fr/prive/mentre/smp-faq/ .
118   
119   If you don't know what to do here, say N.
120   
121 APIC and IO-APIC Support on Uniprocessors
122 CONFIG_X86_UP_IOAPIC
123   APIC (Advanced Programmable Interrupt Controller) is a scheme for
124   delivering hardware interrupt requests to the CPU. It is commonly
125   used on systems with several CPU's. If you have a single-CPU system
126   which uses APIC, you can say Y here to use it. If you say Y here
127   even though your machine doesn't have APIC, then the kernel will
128   still run with no slowdown at all.
129 
130   If you have system with several CPU's, you do not need to say Y
131   here: APIC will be used automatically.
132 
133 Kernel math emulation
134 CONFIG_MATH_EMULATION
135   Linux can emulate a math coprocessor (used for floating point
136   operations) if you don't have one. 486DX and Pentium processors have
137   a math coprocessor built in, 486SX and 386 do not, unless you added
138   a 487DX or 387, respectively. (The messages during boot time can
139   give you some hints here ["man dmesg"].) Everyone needs either a
140   coprocessor or this emulation. 
141 
142   If you don't have a math coprocessor, you need to say Y here; if you
143   say Y here even though you have a coprocessor, the coprocessor will
144   be used nevertheless. (This behavior can be changed with the kernel
145   command line option "no387", which comes handy if your coprocessor
146   is broken. Try "man bootparam" or see the documentation of your boot
147   loader (lilo or loadlin) about how to pass options to the kernel at
148   boot time.) This means that it is a good idea to say Y here if you
149   intend to use this kernel on different machines.
150 
151   More information about the internals of the Linux math coprocessor
152   emulation can be found in arch/i386/math-emu/README.
153 
154   If you are not sure, say Y; apart from resulting in a 66 KB bigger
155   kernel, it won't hurt.
156 
157 Timer and CPU usage LEDs
158 CONFIG_LEDS
159   If you say Y here, the LEDs on your machine will be used
160   to provide useful information about your current system status.
161 
162   If you are compiling a kernel for a NetWinder or EBSA-285, you will
163   be able to select which LEDs are active using the options below. If
164   you are compiling a kernel for the EBSA-110 or the LART however, the
165   red LED will simply flash regularly to indicate that the system is
166   still functional. It is safe to say Y here if you have a CATS
167   system, but the driver will do nothing.
168 
169 Timer LED
170 CONFIG_LEDS_TIMER
171   If you say Y here, one of the system LEDs (the green one on the
172   NetWinder, the amber one on the EBSA285, or the red one on the LART)
173   will flash regularly to indicate that the system is still
174   operational. This is mainly useful to kernel hackers who are
175   debugging unstable kernels.
176 
177   The LART uses the same LED for both Timer LED and CPU usage LED
178   functions. You may choose to use both, but the Timer LED function
179   will overrule the CPU usage LED.
180 
181 CPU usage LED
182 CONFIG_LEDS_CPU
183   If you say Y here, the red LED will be used to give a good real
184   time indication of CPU usage, by lighting whenever the idle task
185   is not currently executing.
186 
187   The LART uses the same LED for both Timer LED and CPU usage LED
188   functions. You may choose to use both, but the Timer LED function
189   will overrule the CPU usage LED.
190 
191 Kernel FP software completion (EXPERIMENTAL)
192 CONFIG_MATHEMU
193   This option is required for IEEE compliant floating point arithmetic
194   on the Alpha. The only time you would ever not say Y is to say M in
195   order to debug the code. Say Y unless you know what you are doing.
196 
197 High Memory support
198 CONFIG_NOHIGHMEM
199   Linux can use up to 64 Gigabytes of physical memory on x86 systems.
200   However, the address space of 32-bit x86 processors is only 4
201   Gigabytes large. That means that, if you have a large amount of
202   physical memory, not all of it can be "permanently mapped" by the
203   kernel. The physical memory that's not permanently mapped is called
204   "high memory".
205 
206   If you are compiling a kernel which will never run on a machine with
207   more than 1 Gigabyte total physical RAM, answer "off" here (default
208   choice and suitable for most users). This will result in a "3GB/1GB"
209   split: 3GB are mapped so that each process sees a 3GB virtual memory
210   space and the remaining part of the 4GB virtual memory space is used
211   by the kernel to permanently map as much physical memory as
212   possible.
213 
214   If the machine has between 1 and 4 Gigabytes physical RAM, then
215   answer "4GB" here.
216 
217   If more than 4 Gigabytes is used then answer "64GB" here. This
218   selection turns Intel PAE (Physical Address Extension) mode on.
219   PAE implements 3-level paging on IA32 processors. PAE is fully
220   supported by Linux, PAE mode is implemented on all recent Intel
221   processors (Pentium Pro and better). NOTE: If you say "64GB" here,
222   then the kernel will not boot on CPUs that don't support PAE!
223 
224   The actual amount of total physical memory will either be
225   auto detected or can be forced by using a kernel command line option
226   such as "mem=256M". (Try "man bootparam" or see the documentation of
227   your boot loader (lilo or loadlin) about how to pass options to the
228   kernel at boot time.) 
229 
230   If unsure, say "off".
231 
232 Normal PC floppy disk support
233 CONFIG_BLK_DEV_FD
234   If you want to use the floppy disk drive(s) of your PC under Linux,
235   say Y. Information about this driver, especially important for IBM
236   Thinkpad users, is contained in Documentation/floppy.txt. That file
237   also contains the location of the Floppy driver FAQ as well as
238   location of the fdutils package used to configure additional
239   parameters of the driver at run time.
240 
241   This driver is also available as a module ( = code which can be
242   inserted in and removed from the running kernel whenever you want).
243   The module will be called floppy.o. If you want to compile it as a
244   module, say M here and read Documentation/modules.txt.
245 
246 Support for PowerMac floppy
247 CONFIG_MAC_FLOPPY
248   If you have a SWIM-3 (Super Woz Integrated Machine 3; from Apple)
249   floppy controller, say Y here. Most commonly found in PowerMacs.
250 
251 RAM disk support
252 CONFIG_BLK_DEV_RAM
253   Saying Y here will allow you to use a portion of your RAM memory as
254   a block device, so that you can make file systems on it, read and
255   write to it and do all the other things that you can do with normal
256   block devices (such as hard drives). It is usually used to load and
257   store a copy of a minimal root file system off of a floppy into RAM
258   during the initial install of Linux. 
259 
260   Note that the kernel command line option "ramdisk=XX" is now
261   obsolete. For details, read Documentation/ramdisk.txt.
262 
263   If you want to compile this as a module ( = code which can be
264   inserted in and removed from the running kernel whenever you want),
265   say M and read Documentation/modules.txt. The module will be called
266   rd.o. 
267 
268   Most normal users won't need the RAM disk functionality, and can
269   thus say N here.
270 
271 Initial RAM disk (initrd) support
272 CONFIG_BLK_DEV_INITRD
273   The initial RAM disk is a RAM disk that is loaded by the boot loader
274   (loadlin or lilo) and that is mounted as root before the normal boot
275   procedure. It is typically used to load modules needed to mount the
276   "real" root file system, etc. See Documentation/initrd.txt for
277   details.
278 
279 Loop device support
280 CONFIG_BLK_DEV_LOOP
281   Saying Y here will allow you to use a regular file as a block
282   device; you can then create a file system on that block device and
283   mount it just as you would mount other block devices such as hard
284   drive partitions, CDROM drives or floppy drives. The loop devices
285   are block special device files with major number 7 and typically
286   called /dev/loop0, /dev/loop1 etc.
287 
288   This is useful if you want to check an ISO 9660 file system before
289   burning the CD, or if you want to use floppy images without first
290   writing them to floppy. Furthermore, some Linux distributions avoid
291   the need for a dedicated Linux partition by keeping their complete
292   root file system inside a DOS FAT file using this loop device
293   driver. 
294 
295   The loop device driver can also be used to "hide" a file system in a
296   disk partition, floppy, or regular file, either using encryption
297   (scrambling the data) or steganography (hiding the data in the low
298   bits of, say, a sound file). This is also safe if the file resides
299   on a remote file server. If you want to do this, you will first have
300   to acquire and install a kernel patch from
301   ftp://ftp.kerneli.org/pub/kerneli/ , and then you need to
302   say Y to this option.
303 
304   Note that alternative ways to use encrypted file systems are
305   provided by the cfs package, which can be gotten from
306   ftp://ftp.kerneli.org/pub/kerneli/net-source/ , and the newer tcfs
307   package, available at http://tcfs.dia.unisa.it/ . You do not need to
308   say Y here if you want to use one of these. However, using cfs
309   requires saying Y to "NFS file system support" below while using
310   tcfs requires applying a kernel patch. An alternative steganography
311   solution is provided by StegFS, also available from
312   ftp://ftp.kerneli.org/pub/kerneli/net-source/ .
313 
314   To use the loop device, you need the losetup utility and a recent
315   version of the mount program, both contained in the util-linux
316   package. The location and current version number of util-linux is
317   contained in the file Documentation/Changes.
318 
319   Note that this loop device has nothing to do with the loopback
320   device used for network connections from the machine to itself.
321 
322   If you want to compile this driver as a module ( = code which can be
323   inserted in and removed from the running kernel whenever you want),
324   say M here and read Documentation/modules.txt. The module will be
325   called loop.o.
326 
327   Most users will answer N here.
328 
329 Network Block Device support
330 CONFIG_BLK_DEV_NBD
331   Saying Y here will allow your computer to be a client for network
332   block devices, i.e. it will be able to use block devices exported by
333   servers (mount file systems on them etc.). Communication between
334   client and server works over TCP/IP networking, but to the client
335   program this is hidden: it looks like a regular local file access to
336   a block device special file such as /dev/nd0. 
337 
338   Network block devices also allows you to run a block-device in
339   userland (making server and client physically the same computer,
340   communicating using the loopback network device).
341   
342   Read Documentation/nbd.txt for more information, especially about
343   where to find the server code, which runs in user space and does not
344   need special kernel support.
345 
346   Note that this has nothing to do with the network file systems NFS
347   or Coda; you can say N here even if you intend to use NFS or Coda.
348 
349   If you want to compile this driver as a module ( = code which can be
350   inserted in and removed from the running kernel whenever you want),
351   say M here and read Documentation/modules.txt. The module will be
352   called nbd.o.
353 
354   If unsure, say N.
355 
356 ATA/IDE/MFM/RLL support
357 CONFIG_IDE
358   If you say Y here, your kernel will be able to manage low cost mass
359   storage units such as ATA/(E)IDE and ATAPI units. The most common
360   cases are IDE hard drives and ATAPI CDROM drives.
361 
362   If your system is pure SCSI and doesn't use these interfaces, you
363   can say N here.
364  
365   Integrated Disk Electronics (IDE aka ATA-1) is a connecting standard
366   for mass storage units such as hard disks. It was designed by
367   Western Digital and Compaq Computer in 1984. It was then named
368   ST506. Quite a number of disks use the IDE interface.
369         
370   AT Attachment (ATA) is the superset of the IDE specifications.
371   ST506 was also called ATA-1.
372 
373   Fast-IDE is ATA-2 (also named Fast ATA), Enhanced IDE (EIDE) is
374   ATA-3. It provides support for larger disks (up to 8.4GB by means of
375   the LBA standard), more disks (4 instead of 2) and for other mass
376   storage units such as tapes and cdrom. UDMA/33 (aka UltraDMA/33) is
377   ATA-4 and provides faster (and more CPU friendly) transfer modes
378   than previous PIO (Programmed processor Input/Output) from previous
379   ATA/IDE standards by means of fast DMA controllers.
380 
381   ATA Packet Interface (ATAPI) is a protocol used by EIDE tape and
382   CDROM drives, similar in many respects to the SCSI protocol.
383   
384   SMART IDE (Self Monitoring, Analysis and Reporting Technology) was
385   designed in order to prevent data corruption and disk crash by
386   detecting pre hardware failure conditions (heat, access time, and
387   the like...). Disks built since June 1995 may follow this
388   standard. The kernel itself don't manage this; however there are
389   quite a number of user programs such as smart that can query the
390   status of SMART parameters disk.
391 
392   If you want to compile this driver as a module ( = code which can be
393   inserted in and removed from the running kernel whenever you want),
394   say M here and read Documentation/modules.txt. The module will be
395   called ide.o.
396 
397   For further information, please read Documentation/ide.txt.
398 
399   If unsure, say Y.
400 
401 Enhanced IDE/MFM/RLL disk/cdrom/tape/floppy support
402 CONFIG_BLK_DEV_IDE
403   If you say Y here, you will use the full-featured IDE driver to
404   control up to ten ATA/IDE interfaces, each being able to serve a
405   "master" and a "slave" device, for a total of up to twenty ATA/IDE
406   disk/cdrom/tape/floppy drives.
407 
408   Useful information about large (>540 MB) IDE disks, multiple
409   interfaces, what to do if ATA/IDE devices are not automatically
410   detected, sound card ATA/IDE ports, module support, and other
411   topics, is contained in Documentation/ide.txt. For detailed
412   information about hard drives, consult the Disk-HOWTO and the
413   Multi-Disk-HOWTO, available from
414   http://www.linuxdoc.org/docs.html#howto .
415 
416   To fine-tune ATA/IDE drive/interface parameters for improved
417   performance, look for the hdparm package at
418   ftp://metalab.unc.edu/pub/Linux/kernel/patches/diskdrives/ .
419 
420   If you want to compile this driver as a module ( = code which can be
421   inserted in and removed from the running kernel whenever you want),
422   say M here and read Documentation/modules.txt and
423   Documentation/ide.txt. The module will be called ide-mod.o. Do not
424   compile this driver as a module if your root file system (the one
425   containing the directory /) is located on an IDE device.
426 
427   If you have one or more IDE drives, say Y or M here. If your system
428   has no IDE drives, or if memory requirements are really tight, you
429   could say N here, and select the "Old hard disk driver" below
430   instead to save about 13 KB of memory in the kernel.
431 
432 Old hard disk (MFM/RLL/IDE) driver
433 CONFIG_BLK_DEV_HD_ONLY
434   There are two drivers for MFM/RLL/IDE hard disks. Most people use
435   the newer enhanced driver, but this old one is still around for two
436   reasons. Some older systems have strange timing problems and seem to
437   work only with the old driver (which itself does not work with some
438   newer systems). The other reason is that the old driver is smaller,
439   since it lacks the enhanced functionality of the new one. This makes
440   it a good choice for systems with very tight memory restrictions, or
441   for systems with only older MFM/RLL/ESDI drives. Choosing the old
442   driver can save 13 KB or so of kernel memory. 
443 
444   If you are unsure, then just choose the Enhanced IDE/MFM/RLL driver
445   instead of this one. For more detailed information, read the
446   Disk-HOWTO, available from
447   http://www.linuxdoc.org/docs.html#howto .
448 
449 Use old disk-only driver on primary interface
450 CONFIG_BLK_DEV_HD_IDE
451   There are two drivers for MFM/RLL/IDE disks. Most people use just
452   the new enhanced driver by itself. This option however installs the
453   old hard disk driver to control the primary IDE/disk interface in
454   the system, leaving the new enhanced IDE driver to take care of only
455   the 2nd/3rd/4th IDE interfaces. Doing this will prevent you from
456   having an IDE/ATAPI CDROM or tape drive connected to the primary IDE
457   interface. Choosing this option may be useful for older systems
458   which have MFM/RLL/ESDI controller+drives at the primary port
459   address (0x1f0), along with IDE drives at the secondary/3rd/4th port
460   addresses. 
461 
462   Normally, just say N here; you will then use the new driver for all
463   4 interfaces.
464 
465 Include IDE/ATA-2 DISK support
466 CONFIG_BLK_DEV_IDEDISK
467   This will include enhanced support for MFM/RLL/IDE hard disks. If
468   you have a MFM/RLL/IDE disk, and there is no special reason to use
469   the old hard disk driver instead, say Y. If you have an SCSI-only
470   system, you can say N here.
471 
472   If you want to compile this driver as a module ( = code which can be
473   inserted in and removed from the running kernel whenever you want),
474   say M here and read Documentation/modules.txt. The module will be
475   called ide-disk.o. Do not compile this driver as a module if your
476   root file system (the one containing the directory /) is located on
477   the IDE disk. If unsure, say Y.
478 
479 Use multi-mode by default
480 CONFIG_IDEDISK_MULTI_MODE
481   If you get this error, try to say Y here:
482 
483   hda: set_multmode: status=0x51 { DriveReady SeekComplete Error }
484   hda: set_multmode: error=0x04 { DriveStatusError }
485 
486   If in doubt, say N.
487 
488 Include IDE/ATAPI CDROM support
489 CONFIG_BLK_DEV_IDECD
490   If you have a CDROM drive using the ATAPI protocol, say Y. ATAPI is
491   a newer protocol used by IDE CDROM and TAPE drives, similar to the
492   SCSI protocol. Most new CDROM drives use ATAPI, including the
493   NEC-260, Mitsumi FX400, Sony 55E, and just about all non-SCSI
494   double(2X) or better speed drives.
495 
496   If you say Y here, the CDROM drive will be identified at boot time
497   along with other IDE devices, as "hdb" or "hdc", or something
498   similar (check the boot messages with dmesg). If this is your only
499   CDROM drive, you can say N to all other CDROM options, but be sure
500   to say Y or M to "ISO 9660 CDROM file system support".
501 
502   Read the CDROM-HOWTO, available from
503   http://www.linuxdoc.org/docs.html#howto and the file
504   Documentation/cdrom/ide-cd. Note that older versions of lilo (the
505   Linux boot loader) cannot properly deal with IDE/ATAPI CDROMs, so
506   install lilo-16 or higher, available from
507   ftp://metalab.unc.edu/pub/Linux/system/boot/lilo .
508 
509   If you want to compile the driver as a module ( = code which can be
510   inserted in and removed from the running kernel whenever you want),
511   say M here and read Documentation/modules.txt. The module will be
512   called ide-cd.o.
513 
514 Include IDE/ATAPI TAPE support
515 CONFIG_BLK_DEV_IDETAPE
516   If you have an IDE tape drive using the ATAPI protocol, say Y.
517   ATAPI is a newer protocol used by IDE tape and CDROM drives, similar
518   to the SCSI protocol. If you have an SCSI tape drive however, you
519   can say N here.
520 
521   You should also say Y if you have an OnStream DI-30 tape drive; this
522   will not work with the SCSI protocol, until there is support for the
523   SC-30 and SC-50 versions.
524 
525   If you say Y here, the tape drive will be identified at boot time
526   along with other IDE devices, as "hdb" or "hdc", or something
527   similar, and will be mapped to a character device such as "ht0"
528   (check the boot messages with dmesg). Be sure to consult the
529   drivers/ide/ide-tape.c and Documentation/ide.txt files for usage
530   information.
531 
532   If you want to compile the driver as a module ( = code which can be
533   inserted in and removed from the running kernel whenever you want),
534   say M here and read Documentation/modules.txt. The module will be
535   called ide-tape.o.
536 
537 Include IDE/ATAPI FLOPPY support
538 CONFIG_BLK_DEV_IDEFLOPPY
539   If you have an IDE floppy drive which uses the ATAPI protocol,
540   answer Y. ATAPI is a newer protocol used by IDE CDROM/tape/floppy
541   drives, similar to the SCSI protocol. 
542 
543   The LS-120 and the IDE/ATAPI Iomega ZIP drive are also supported by
544   this driver. For information about jumper settings and the question
545   of when a ZIP drive uses a partition table, see
546   http://www.win.tue.nl/~aeb/linux/zip/zip-1.html .
547   (ATAPI PD-CD/CDR drives are not supported by this driver; support
548   for PD-CD/CDR drives is available if you answer Y to 
549   "SCSI emulation support", below).
550 
551   If you say Y here, the FLOPPY drive will be identified along with
552   other IDE devices, as "hdb" or "hdc", or something similar (check
553   the boot messages with dmesg).
554 
555   If you want to compile the driver as a module ( = code which can be
556   inserted in and removed from the running kernel whenever you want),
557   say M here and read Documentation/modules.txt. The module will be
558   called ide-floppy.o.
559 
560 SCSI emulation support
561 CONFIG_BLK_DEV_IDESCSI
562   This will provide SCSI host adapter emulation for IDE ATAPI devices,
563   and will allow you to use a SCSI device driver instead of a native
564   ATAPI driver.
565 
566   This is useful if you have an ATAPI device for which no native
567   driver has been written (for example, an ATAPI PD-CD or CDR drive);
568   you can then use this emulation together with an appropriate SCSI
569   device driver. In order to do this, say Y here and to "SCSI support"
570   and "SCSI generic support", below. You must then provide the kernel
571   command line "hdx=scsi" (try "man bootparam" or see the
572   documentation of your boot loader (lilo or loadlin) about how to
573   pass options to the kernel at boot time) for devices if you want the
574   native EIDE sub-drivers to skip over the native support, so that
575   this SCSI emulation can be used instead. This is required for use of
576   CD-RW's.
577 
578   Note that this option does NOT allow you to attach SCSI devices to a
579   box that doesn't have a SCSI host adapter installed.
580 
581   If both this SCSI emulation and native ATAPI support are compiled
582   into the kernel, the native support will be used.
583 
584 ISA-PNP EIDE support
585 CONFIG_BLK_DEV_ISAPNP
586   If you have an ISA EIDE card that is PnP (Plug and Play) and
587   requires setup first before scanning for devices, say Y here.
588 
589   If unsure, say N.
590 
591 CMD640 chipset bugfix/support
592 CONFIG_BLK_DEV_CMD640
593   The CMD-Technologies CMD640 IDE chip is used on many common 486 and
594   Pentium motherboards, usually in combination with a "Neptune" or
595   "SiS" chipset. Unfortunately, it has a number of rather nasty
596   design flaws that can cause severe data corruption under many common
597   conditions. Say Y here to include code which tries to automatically
598   detect and correct the problems under Linux. This option also
599   enables access to the secondary IDE ports in some CMD640 based
600   systems. 
601 
602   This driver will work automatically in PCI based systems (most new
603   systems have PCI slots). But if your system uses VESA local bus
604   (VLB) instead of PCI, you must also supply a kernel boot parameter
605   to enable the CMD640 bugfix/support: "ide0=cmd640_vlb". (Try "man
606   bootparam" or see the documentation of your boot loader about how to
607   pass options to the kernel.)
608 
609   The CMD640 chip is also used on add-in cards by Acculogic, and on
610   the "CSA-6400E PCI to IDE controller" that some people have. For
611   details, read Documentation/ide.txt. 
612 
613 CMD640 enhanced support
614 CONFIG_BLK_DEV_CMD640_ENHANCED
615   This option includes support for setting/autotuning PIO modes and
616   prefetch on CMD640 IDE interfaces. For details, read
617   Documentation/ide.txt. If you have a CMD640 IDE interface and your
618   BIOS does not already do this for you, then say Y here. Otherwise
619   say N.
620 
621 RZ1000 chipset bugfix/support
622 CONFIG_BLK_DEV_RZ1000
623   The PC-Technologies RZ1000 IDE chip is used on many common 486 and
624   Pentium motherboards, usually along with the "Neptune" chipset.
625   Unfortunately, it has a rather nasty design flaw that can cause
626   severe data corruption under many conditions. Say Y here to include
627   code which automatically detects and corrects the problem under
628   Linux. This may slow disk throughput by a few percent, but at least
629   things will operate 100% reliably. 
630 
631 Generic PCI IDE chipset support
632 CONFIG_BLK_DEV_IDEPCI
633   Say Y here for PCI systems which use IDE drive(s).
634   This option helps the IDE driver to automatically detect and
635   configure all PCI-based IDE interfaces in your system.
636   
637 Support for sharing PCI IDE interrupts
638 CONFIG_IDEPCI_SHARE_IRQ
639   Some ATA/IDE chipsets have hardware support which allows for
640   sharing a single IRQ with other cards. To enable support for
641   this in the ATA/IDE driver, say Y here.
642 
643   It is safe to say Y to this question, in most cases.
644   If unsure, say N.
645 
646 Generic PCI bus-master DMA support
647 CONFIG_BLK_DEV_IDEDMA_PCI
648   If your PCI system uses IDE drive(s) (as opposed to SCSI, say) and
649   is capable of bus-master DMA operation (most Pentium PCI systems),
650   you will want to say Y here to reduce CPU overhead. You can then use
651   the "hdparm" utility to enable DMA for drives for which it was not
652   enabled automatically. By default, DMA is not enabled automatically
653   for these drives, but you can change that by saying Y to the
654   following question "Use DMA by default when available". You can get
655   the latest version of the hdparm utility from
656   ftp://metalab.unc.edu/pub/Linux/system/hardware/ .
657 
658   Read the comments at the beginning of drivers/ide/ide-dma.c and
659   the file Documentation/ide.txt for more information.
660 
661   It is safe to say Y to this question.
662 
663 Good-Bad DMA Model-Firmware (EXPERIMENTAL)
664 CONFIG_IDEDMA_NEW_DRIVE_LISTINGS
665   If you say Y here, the model and firmware revision of your drive
666   will be compared against a blacklist of buggy drives that claim to
667   be (U)DMA capable but aren't. This is a blanket on/off test with no
668   speed limit options.
669 
670   Straight GNU GCC 2.7.3/2.8.X compilers are known to be safe;
671   whereas, many versions of EGCS have a problem and miscompile if you
672   say Y here.
673 
674   If in doubt, say N.
675 
676 Boot off-board chipsets first support
677 CONFIG_BLK_DEV_OFFBOARD
678   Normally, IDE controllers built into the motherboard (on-board
679   controllers) are assigned to ide0 and ide1 while those on add-in PCI
680   cards (off-board controllers) are relegated to ide2 and ide3.
681   Answering Y here will allow you to reverse the situation, with
682   off-board controllers on ide0/1 and on-board controllers on ide2/3.
683   This can improve the usability of some boot managers such as lilo
684   when booting from a drive on an off-board controller.
685 
686   If you say Y here, and you actually want to reverse the device scan
687   order as explained above, you also need to issue the kernel command
688   line option "ide=reverse". (Try "man bootparam" or see the
689   documentation of your boot loader (lilo or loadlin) about how to
690   pass options to the kernel at boot time.)
691 
692   Note that, if you do this, the order of the hd* devices will be
693   rearranged which may require modification of fstab and other files.
694 
695   If in doubt, say N.
696 
697 Use DMA by default when available
698 CONFIG_IDEDMA_PCI_AUTO
699   Prior to kernel version 2.1.112, Linux used to automatically use
700   DMA for IDE drives and chipsets which support it. Due to concerns
701   about a couple of cases where buggy hardware may have caused damage,
702   the default is now to NOT use DMA automatically. To revert to the
703   previous behaviour, say Y to this question.
704 
705   If you suspect your hardware is at all flakey, say N here.
706   Do NOT email the IDE kernel people regarding this issue!
707 
708   It is normally safe to answer Y to this question unless your
709   motherboard uses a VIA VP2 chipset, in which case you should say N.
710 
711 IGNORE word93 Validation BITS
712 CONFIG_IDEDMA_IVB
713   Since various rules were applied and created ... et al. as it relates
714   the detection of vaild cable signals.  This is a result of unclear terms
715   in ATA-4 and ATA-5 standards.
716 
717   It is normally safe to answer Y; however, the default is N.
718 
719 Various ATA, Work(s) In Progress (EXPERIMENTAL)
720 CONFIG_IDEDMA_PCI_WIP
721   If you enable this you will be able to use and test highly
722   developmental projects. If you say N, this configure script will
723   simply skip those options.
724 
725   It is SAFEST to say N to this question.
726 
727 3ware Hardware ATA-RAID support
728 CONFIG_BLK_DEV_3W_XXXX_RAID
729   3ware is the only hardware ATA-Raid product in Linux to date.
730   This card is 2,4, or 8 channel master mode support only.
731   SCSI support required!!!
732 
733   http://www.3ware.com/
734 
735   Please read the comments at the top of drivers/scsi/3w-xxxx.c  
736 
737 AEC62XX chipset support
738 CONFIG_BLK_DEV_AEC62XX
739   This driver adds up to 4 more EIDE devices sharing a single
740   interrupt. This add-on card is a bootable PCI UDMA controller. In
741   order to get this card to initialize correctly in some cases, you
742   should say Y here, and preferably also to "Use DMA by default when
743   available".
744 
745   The ATP850U/UF is an UltraDMA 33 chipset base.
746   The ATP860 is an UltraDMA 66 chipset base.
747   The ATP860M(acintosh) version is an UltraDMA 66 chipset base.
748 
749   Please read the comments at the top of drivers/ide/aec62xx.c
750   If you say Y here, then say Y to "Use DMA by default when available" as
751   well.
752 
753 AEC62XX Tuning support
754 CONFIG_AEC62XX_TUNING
755   Please read the comments at the top of drivers/ide/aec62xx.c  
756   If unsure, say N.
757 
758 ALI M15x3 chipset support
759 CONFIG_BLK_DEV_ALI15X3
760   This driver ensures (U)DMA support for ALI 1533, 1543 and 1543C
761   onboard chipsets.  It also tests for Simplex mode and enables
762   normal dual channel support.
763 
764   If you say Y here, you also need to say Y to "Use DMA by default
765   when available", above.
766   Please read the comments at the top of drivers/ide/alim15x3.c
767 
768   If unsure, say N.
769 
770 ALI M15x3 WDC support (DANGEROUS)
771 CONFIG_WDC_ALI15X3
772   This allows for UltraDMA support for WDC drives that ignore CRC
773   checking. You are a fool for enabling this option, but there have
774   been requests. DO NOT COMPLAIN IF YOUR DRIVE HAS FS CORRUPTION, IF
775   YOU ENABLE THIS! No one will listen, just laugh for ignoring this
776   SERIOUS WARNING.
777 
778   Using this option can allow WDC drives to run at ATA-4/5 transfer
779   rates with only an ATA-2 support structure.
780 
781   SAY NO!
782 
783 AMD7409 chipset support
784 CONFIG_BLK_DEV_AMD7409
785   This driver ensures (U)DMA support for the AMD756 Viper chipset.
786 
787   If you say Y here, you also need to say Y to "Use DMA by default
788   when available", above.
789   Please read the comments at the top of drivers/ide/amd7409.c
790 
791   If unsure, say N.
792 
793 AMD Viper ATA-66 Override support (WIP)
794 CONFIG_AMD7409_OVERRIDE
795   This option auto-forces the ata66 flag.
796   This effect can be also invoked by calling "idex=ata66"
797   If unsure, say N.
798 
799 CMD64X chipset support
800 CONFIG_BLK_DEV_CMD64X
801   Say Y here if you have an IDE controller which uses any of these
802   chipsets: CMD643, CMD646, or CMD648.
803 
804 CY82C693 chipset support
805 CONFIG_BLK_DEV_CY82C693
806   This driver adds detection and support for the CY82C693 chipset
807   used on Digital's PC-Alpha 164SX boards.
808 
809   If you say Y here, you need to say Y to "Use DMA by default
810   when available" as well.
811 
812 Cyrix CS5530 MediaGX chipset support
813 CONFIG_BLK_DEV_CS5530
814   Include support for UDMA on the Cyrix MediaGX 5530 chipset. This
815   will automatically be detected and configured if found.
816 
817   It is safe to say Y to this question.
818 
819   People with SCSI-only systems should say N here. If unsure, say Y.
820 
821 HPT34X chipset support
822 CONFIG_BLK_DEV_HPT34X
823   This driver adds up to 4 more EIDE devices sharing a single
824   interrupt. The HPT343 chipset in its current form is a non-bootable
825   controller; the HPT345/HPT363 chipset is a bootable (needs BIOS FIX)
826   PCI UDMA controllers. This driver requires dynamic tuning of the
827   chipset during the ide-probe at boot time. It is reported to support
828   DVD II drives, by the manufacturer.
829 
830 HPT34X AUTODMA support (WIP)
831 CONFIG_HPT34X_AUTODMA
832   This is a dangerous thing to attempt currently! Please read the
833   comments at the top of drivers/ide/hpt34x.c If you say Y here,
834   then say Y to "Use DMA by default when available" as well.
835 
836   If unsure, say N.
837 
838 HPT366 chipset support
839 CONFIG_BLK_DEV_HPT366
840   HPT366 is an Ultra DMA chipset for ATA-66.
841   HPT368 is an Ultra DMA chipset for ATA-66 RAID Based.
842   HPT370 is an Ultra DMA chipset for ATA-100.
843  
844   This driver adds up to 4 more EIDE devices sharing a single
845   interrupt. 
846 
847   The HPT366 chipset in its current form is bootable. One solution
848   for this problem are special LILO commands for redirecting the
849   reference to device 0x80. The other solution is to say Y to "Boot
850   off-board chipsets first support" (CONFIG_BLK_DEV_OFFBOARD) unless
851   your mother board has the chipset natively mounted. Regardless one
852   should use the fore mentioned option and call at LILO or include
853   "ide=reverse" in LILO's append-line.
854 
855   This driver requires dynamic tuning of the chipset during the
856   ide-probe at boot. It is reported to support DVD II drives, by the
857   manufacturer.
858 
859 NS87415 support (EXPERIMENTAL)
860 CONFIG_BLK_DEV_NS87415
861   This driver adds detection and support for the NS87415 chip
862   (used in SPARC64, among others).
863 
864   Please read the comments at the top of drivers/ide/ns87415.c.
865 
866 OPTi 82C621 enhanced support (EXPERIMENTAL)
867 CONFIG_BLK_DEV_OPTI621
868   This is a driver for the OPTi 82C621 EIDE controller.
869   Please read the comments at the top of drivers/ide/opti621.c.
870 
871 ServerWorks OSB4 chipset support (EXPERIMENTAL)
872 CONFIG_BLK_DEV_OSB4
873   This driver adds PIO/DMA support for the Serverworks OSB4 chipset
874 
875 Intel PIIXn chipsets support
876 CONFIG_BLK_DEV_PIIX
877   This driver adds PIO mode setting and tuning for all PIIX IDE
878   controllers by Intel.  Since the BIOS can sometimes improperly tune
879   PIO 0-4 mode settings, this allows dynamic tuning of the chipset
880   via the standard end-user tool 'hdparm'.
881 
882   Please read the comments at the top of drivers/ide/piix.c.
883 
884   If you say Y here, you should also say Y to "PIIXn Tuning support",
885   below.
886 
887   If unsure, say N.
888 
889 PIIXn Tuning support
890 CONFIG_PIIX_TUNING
891   This driver extension adds DMA mode setting and tuning for all PIIX
892   IDE controllers by Intel. Since the BIOS can sometimes improperly
893   set up the device/adapter combination and speed limits, it has
894   become a necessity to back/forward speed devices as needed.
895 
896   Case 430HX/440FX PIIX3 need speed limits to reduce UDMA to DMA mode
897   2 if the BIOS can not perform this task at initialization.
898 
899   If unsure, say N.
900 
901 PROMISE PDC20246/PDC20262/PDC20267 support
902 CONFIG_BLK_DEV_PDC202XX
903   Promise Ultra33 or PDC20246
904   Promise Ultra66 or PDC20262
905   Promise Ultra100 or PDC20265/PDC20267
906 
907   This driver adds up to 4 more EIDE devices sharing a single
908   interrupt. This add-on card is a bootable PCI UDMA controller. Since
909   multiple cards can be installed and there are BIOS ROM problems that
910   happen if the BIOS revisions of all installed cards (three-max) do
911   not match, the driver attempts to do dynamic tuning of the chipset
912   at boot-time for max-speed. Ultra33 BIOS 1.25 or newer is required
913   for more than one card. This card may require that you say Y to
914   "Special UDMA Feature (EXPERIMENTAL)".
915 
916   If you say Y here, you need to say Y to "Use DMA by default when
917   available" as well.
918 
919   Please read the comments at the top of drivers/ide/pdc202xx.c
920 
921   If unsure, say N.
922 
923 Special UDMA Feature (EXPERIMENTAL)
924 CONFIG_PDC202XX_BURST
925   For PDC20246, PDC20262, PDC20265 and PDC20267 Ultra DMA chipsets.
926   Designed originally for PDC20246/Ultra33 that has BIOS setup
927   failures when using 3 or more cards.
928 
929   Unknown for PDC20265/PDC20267 Ultra DMA 100.
930 
931   Please read the comments at the top of drivers/ide/pdc202xx.c
932 
933   If unsure, say N.
934 
935 SiS5513 chipset support
936 CONFIG_BLK_DEV_SIS5513
937   This driver ensures (U)DMA support for SIS5513 chipset based
938   mainboards. SiS620/530 UDMA mode 4, SiS5600/5597 UDMA mode 2, all
939   other DMA mode 2 limited chipsets are unsupported to date.
940 
941   If you say Y here, you need to say Y to "Use DMA by default when
942   available" as well.
943 
944   Please read the comments at the top of drivers/ide/sis5513.c
945 
946 SLC90E66 chipset support
947 CONFIG_BLK_DEV_SLC90E66
948   This driver ensures (U)DMA support for Victroy66 SouthBridges for
949   SMsC with Intel NorthBridges.  This is an Ultra66 based chipset.
950   The nice thing about it is that you can mix Ultra/DMA/PIO devices
951   and it will handle timing cycles.  Since this is an improved look-a-like
952   to the PIIX4 it should be a nice addition.
953 
954   If you say Y here, you need to say Y to "Use DMA by default when
955   available" as well.
956 
957   Please read the comments at the top of drivers/ide/slc90e66.c
958 
959 Winbond SL82c105 support
960 CONFIG_BLK_DEV_SL82C105
961   If you have a Winbond SL82c105 IDE controller, say Y here to enable
962   special configuration for this chip. This is common on various CHRP
963   motherboards, but could be used elsewhere. If in doubt, say Y.
964 
965 Tekram TRM290 chipset support (EXPERIMENTAL)
966 CONFIG_BLK_DEV_TRM290
967   This driver adds support for bus master DMA transfers
968   using the Tekram TRM290 PCI IDE chip. Volunteers are
969   needed for further tweaking and development.
970   Please read the comments at the top of drivers/ide/trm290.c.
971 
972 VIA82CXXX chipset support
973 CONFIG_BLK_DEV_VIA82CXXX
974   This allows you to configure your chipset for a better use while
975   running (U)DMA: it will allow you to enable efficiently the second
976   channel dma usage, as it may not be set by BIOS. It allows you to
977   pass a kernel command line at boot time in order to set fifo
978   config. If no command line is provided, it will try to set fifo
979   configuration at its best. It will allow you to get information from
980   /proc/ide/via provided you enabled "proc" support.
981 
982   Please read the comments at the top of drivers/ide/via82cxxx.c
983 
984   If you say Y here, then say Y to "Use DMA by default when available"
985   as well.
986 
987   If unsure, say N.
988 
989 VIA82CXXX Tuning support (WIP)
990 CONFIG_VIA82CXXX_TUNING
991   Please read the comments at the top of drivers/ide/via82cxxx.c
992 
993   If unsure, say N.
994 
995 Other IDE chipset support
996 CONFIG_IDE_CHIPSETS
997   Say Y here if you want to include enhanced support for various IDE
998   interface chipsets used on motherboards and add-on cards. You can
999   then pick your particular IDE chip from among the following options.
1000   This enhanced support may be necessary for Linux to be able to
1001   access the 3rd/4th drives in some systems. It may also enable
1002   setting of higher speed I/O rates to improve system performance with
1003   these chipsets. Most of these also require special kernel boot
1004   parameters to actually turn on the support at runtime; you can find
1005   a list of these in the file Documentation/ide.txt.
1006   
1007   People with SCSI-only systems can say N here. 
1008 
1009 Generic 4 drives/port support
1010 CONFIG_BLK_DEV_4DRIVES
1011   Certain older chipsets, including the Tekram 690CD, use a single set
1012   of I/O ports at 0x1f0 to control up to four drives, instead of the
1013   customary two drives per port. Support for this can be enabled at
1014   runtime using the "ide0=four" kernel boot parameter if you say Y
1015   here.
1016 
1017 ALI M14xx support
1018 CONFIG_BLK_DEV_ALI14XX
1019   This driver is enabled at runtime using the "ide0=ali14xx" kernel
1020   boot parameter. It enables support for the secondary IDE interface
1021   of the ALI M1439/1443/1445/1487/1489 chipsets, and permits faster
1022   I/O speeds to be set as well. See the files Documentation/ide.txt
1023   and drivers/ide/ali14xx.c for more info.
1024 
1025 DTC-2278 support
1026 CONFIG_BLK_DEV_DTC2278
1027   This driver is enabled at runtime using the "ide0=dtc2278" kernel
1028   boot parameter. It enables support for the secondary IDE interface
1029   of the DTC-2278 card, and permits faster I/O speeds to be set as
1030   well. See the Documentation/ide.txt and drivers/ide/dtc2278.c
1031   files for more info.
1032 
1033 Holtek HT6560B support
1034 CONFIG_BLK_DEV_HT6560B
1035   This driver is enabled at runtime using the "ide0=ht6560b" kernel
1036   boot parameter. It enables support for the secondary IDE interface
1037   of the Holtek card, and permits faster I/O speeds to be set as well.
1038   See the Documentation/ide.txt and drivers/ide/ht6560b.c files for
1039   more info.
1040 
1041 PROMISE DC4030 support (EXPERIMENTAL)
1042 CONFIG_BLK_DEV_PDC4030
1043   This driver provides support for the secondary IDE interface and
1044   cache of Promise IDE chipsets, e.g. DC4030 and DC5030. This driver
1045   is known to incur timeouts/retries during heavy I/O to drives
1046   attached to the secondary interface. CDROM and TAPE devices are not
1047   supported yet. This driver is enabled at runtime using the
1048   "ide0=dc4030" kernel boot parameter. See the Documentation/ide.txt
1049   and drivers/ide/pdc4030.c files for more info.
1050 
1051 QDI QD6580 support
1052 CONFIG_BLK_DEV_QD6580
1053   This driver is enabled at runtime using the "ide0=qd6580" kernel
1054   boot parameter. It permits faster I/O speeds to be set. See the
1055   files Documentation/ide.txt and drivers/ide/qd6580.c for more
1056   info.
1057 
1058 UMC 8672 support
1059 CONFIG_BLK_DEV_UMC8672
1060   This driver is enabled at runtime using the "ide0=umc8672" kernel
1061   boot parameter. It enables support for the secondary IDE interface
1062   of the UMC-8672, and permits faster I/O speeds to be set as well.
1063   See the files Documentation/ide.txt and drivers/ide/umc8672.c for
1064   more info.
1065 
1066 Amiga builtin Gayle IDE interface support
1067 CONFIG_BLK_DEV_GAYLE
1068   This is the IDE driver for the builtin IDE interface on some Amiga
1069   models. It supports both the `A1200 style' (used in A600 and A1200)
1070   and `A4000 style' (used in A4000 and A4000T) of the Gayle IDE
1071   interface. Say Y if you have such an Amiga model and want to use IDE
1072   devices (hard disks, CD-ROM drives, etc.) that are connected to the
1073   builtin IDE interface.
1074 
1075 Falcon IDE interface support
1076 CONFIG_BLK_DEV_FALCON_IDE
1077   This is the IDE driver for the builtin IDE interface on the Atari
1078   Falcon. Say Y if you have a Falcon and want to use IDE devices (hard
1079   disks, CD-ROM drives, etc.) that are connected to the builtin IDE
1080   interface.
1081 
1082 Amiga Buddha/Catweasel IDE interface support (EXPERIMENTAL)
1083 CONFIG_BLK_DEV_BUDDHA
1084   This is the IDE driver for the IDE interfaces on the Buddha and
1085   Catweasel expansion boards.  It supports up to two interfaces on the
1086   Buddha and three on the Catweasel.
1087 
1088   Say Y if you have a Buddha or Catweasel expansion board and want to
1089   use IDE devices (hard disks, CD-ROM drives, etc.) that are connected
1090   to one of its IDE interfaces.
1091 
1092 Amiga IDE Doubler support (EXPERIMENTAL)
1093 CONFIG_BLK_DEV_IDEDOUBLER
1094   This driver provides support for the so-called `IDE doublers' (made
1095   by various manufacturers, e.g. Eyetech) that can be connected to the
1096   builtin IDE interface of some Amiga models. Using such an IDE
1097   doubler, you can connect up to four instead of two IDE devices on
1098   the Amiga's builtin IDE interface.
1099 
1100   Note that the normal Amiga Gayle IDE driver may not work correctly
1101   if you have an IDE doubler and don't enable this driver!
1102 
1103   Say Y if you have an IDE doubler.  The driver is enabled at kernel
1104   runtime using the "ide=doubler" kernel boot parameter.
1105 
1106 Support for PowerMac IDE devices (must also enable IDE)
1107 CONFIG_BLK_DEV_IDE_PMAC
1108   This driver provides support for the built-in IDE controller on most
1109   of the recent Apple Power Macintoshes and PowerBooks.
1110   If unsure, say Y.
1111 
1112 PowerMac IDE DMA support
1113 CONFIG_BLK_DEV_IDEDMA_PMAC
1114   This option allows the driver for the built-in IDE controller on
1115   Power Macintoshes and PowerBooks to use DMA (direct memory access)
1116   to transfer data to and from memory.  Saying Y is safe and improves
1117   performance.
1118 
1119 Use DMA by default
1120 CONFIG_BLK_DEV_IDEDMA_PMAC_AUTO
1121   This option allows the driver for the built-in IDE controller on
1122   Power Macintoshes and PowerBooks to use DMA automatically, without
1123   it having to be explicitly enabled.  This option is provided because
1124   of concerns about a couple of cases where using DMA on buggy PC
1125   hardware may have caused damage.  Saying Y should be safe on all
1126   Apple machines.
1127 
1128 Macintosh Quadra/Powerbook IDE interface support
1129 CONFIG_BLK_DEV_MAC_IDE
1130   This is the IDE driver for the builtin IDE interface on some m68k
1131   Macintosh models. It supports both the `Quadra style' (used in
1132   Quadra/ Centris 630 and Performa 588 models) and `Powerbook style'
1133   (used in the Powerbook 150 and 190 models) IDE interface.
1134 
1135   Say Y if you have such an Macintosh model and want to use IDE
1136   devices (hard disks, CD-ROM drives, etc.) that are connected to the
1137   builtin IDE interface.
1138 
1139 ICS IDE interface support
1140 CONFIG_BLK_DEV_IDE_ICSIDE
1141   On Acorn systems, say Y here if you wish to use the ICS IDE
1142   interface card.  This is not required for ICS partition support.
1143   If you are unsure, say N to this.
1144 
1145 ICS DMA support
1146 CONFIG_BLK_DEV_IDEDMA_ICS
1147   Say Y here if you want to add DMA (Direct Memory Access) support to
1148   the ICS IDE driver.
1149 
1150 Use ICS DMA by default
1151 CONFIG_IDEDMA_ICS_AUTO
1152   Prior to kernel version 2.1.112, Linux used to automatically use
1153   DMA for IDE drives and chipsets which support it. Due to concerns
1154   about a couple of cases where buggy hardware may have caused damage,
1155   the default is now to NOT use DMA automatically. To revert to the
1156   previous behaviour, say Y to this question.
1157 
1158   If you suspect your hardware is at all flakey, say N here.
1159   Do NOT email the IDE kernel people regarding this issue!
1160 
1161 XT hard disk support
1162 CONFIG_BLK_DEV_XD
1163   Very old 8 bit hard disk controllers used in the IBM XT computer
1164   will be supported if you say Y here. 
1165 
1166   If you want to compile the driver as a module ( = code which can be
1167   inserted in and removed from the running kernel whenever you want),
1168   say M here and read Documentation/modules.txt. The module will be
1169   called xd.o. 
1170 
1171   It's pretty unlikely that you have one of these: say N.
1172 
1173 PS/2 ESDI hard disk support
1174 CONFIG_BLK_DEV_PS2
1175   Say Y here if you have a PS/2 machine with a MCA bus and an ESDI
1176   hard disk.
1177   
1178   If you want to compile the driver as a module ( = code which can be
1179   inserted in and removed from the running kernel whenever you want),
1180   say M here and read Documentation/modules.txt. The module will be
1181   called ps2esdi.o.
1182 
1183 Mylex DAC960/DAC1100 PCI RAID Controller support
1184 CONFIG_BLK_DEV_DAC960
1185   This driver adds support for the Mylex DAC960, AcceleRAID, and
1186   eXtremeRAID PCI RAID controllers. See the file
1187   Documentation/README.DAC960 for further information about this
1188   driver.
1189 
1190   If you want to compile the driver as a module ( = code which can be
1191   inserted in and removed from the running kernel whenever you want),
1192   say M here and read Documentation/modules.txt.  The module will be
1193   called DAC960.o. 
1194 
1195 Parallel port IDE device support
1196 CONFIG_PARIDE
1197   There are many external CD-ROM and disk devices that connect through
1198   your computer's parallel port. Most of them are actually IDE devices
1199   using a parallel port IDE adapter. This option enables the PARIDE
1200   subsystem which contains drivers for many of these external drives.
1201   Read Documentation/paride.txt for more information.
1202 
1203   If you have said Y to the "Parallel-port support" configuration
1204   option, you may share a single port between your printer and other
1205   parallel port devices. Answer Y to build PARIDE support into your
1206   kernel, or M if you would like to build it as a loadable module. If
1207   your parallel port support is in a loadable module, you must build
1208   PARIDE as a module. If you built PARIDE support into your kernel,
1209   you may still build the individual protocol modules and high-level
1210   drivers as loadable modules. If you build this support as a module,
1211   it will be called paride.o.
1212 
1213   To use the PARIDE support, you must say Y or M here and also to at
1214   least one high-level driver (e.g. "Parallel port IDE disks",
1215   "Parallel port ATAPI CD-ROMs", "Parallel port ATAPI disks" etc.) and
1216   to at least one protocol driver (e.g. "ATEN EH-100 protocol",
1217   "MicroSolutions backpack protocol", "DataStor Commuter protocol"
1218   etc.).
1219 
1220 Parallel port IDE disks
1221 CONFIG_PARIDE_PD
1222   This option enables the high-level driver for IDE-type disk devices 
1223   connected through a parallel port. If you chose to build PARIDE 
1224   support into your kernel, you may answer Y here to build in the 
1225   parallel port IDE driver, otherwise you should answer M to build 
1226   it as a loadable module. The module will be called pd.o. You 
1227   must also have at least one parallel port protocol driver in your 
1228   system. Among the devices supported by this driver are the SyQuest 
1229   EZ-135, EZ-230 and SparQ drives, the Avatar Shark and the backpack
1230   hard drives from MicroSolutions.
1231 
1232 Parallel port ATAPI CD-ROMs
1233 CONFIG_PARIDE_PCD
1234   This option enables the high-level driver for ATAPI CD-ROM devices
1235   connected through a parallel port. If you chose to build PARIDE
1236   support into your kernel, you may answer Y here to build in the
1237   parallel port ATAPI CD-ROM driver, otherwise you should answer M to
1238   build it as a loadable module. The module will be called pcd.o. You
1239   must also have at least one parallel port protocol driver in your
1240   system. Among the devices supported by this driver are the
1241   MicroSolutions backpack CD-ROM drives and the Freecom Power CD. If
1242   you have such a CD-ROM drive, you should also say Y or M to "ISO
1243   9660 CDROM file system support" below, because that's the file
1244   system used on CDROMs.
1245 
1246 Parallel port ATAPI disks
1247 CONFIG_PARIDE_PF
1248   This option enables the high-level driver for ATAPI disk devices
1249   connected through a parallel port. If you chose to build PARIDE
1250   support into your kernel, you may answer Y here to build in the
1251   parallel port ATAPI disk driver, otherwise you should answer M
1252   to build it as a loadable module. The module will be called pf.o.
1253   You must also have at least one parallel port protocol driver in
1254   your system. Among the devices supported by this driver are the
1255   MicroSolutions backpack PD/CD drive and the Imation Superdisk
1256   LS-120 drive.
1257 
1258 Parallel port ATAPI tapes
1259 CONFIG_PARIDE_PT
1260   This option enables the high-level driver for ATAPI tape devices
1261   connected through a parallel port. If you chose to build PARIDE
1262   support into your kernel, you may answer Y here to build in the
1263   parallel port ATAPI disk driver, otherwise you should answer M
1264   to build it as a loadable module. The module will be called pt.o.
1265   You must also have at least one parallel port protocol driver in
1266   your system. Among the devices supported by this driver is the
1267   parallel port version of the HP 5GB drive.
1268 
1269 Parallel port generic ATAPI devices
1270 CONFIG_PARIDE_PG
1271   This option enables a special high-level driver for generic ATAPI
1272   devices connected through a parallel port. The driver allows user
1273   programs, such as cdrecord, to send ATAPI commands directly to a
1274   device. 
1275 
1276   If you chose to build PARIDE support into your kernel, you may
1277   answer Y here to build in the parallel port generic ATAPI driver,
1278   otherwise you should answer M to build it as a loadable module. The
1279   module will be called pg.o.
1280 
1281   You must also have at least one parallel port protocol driver in
1282   your system.
1283 
1284   This driver implements an API loosely related to the generic SCSI
1285   driver. See include/linux/pg.h for details.
1286 
1287   You can obtain the most recent version of cdrecord from
1288   ftp://ftp.fokus.gmd.de/pub/unix/cdrecord/ . Versions 1.6.1a3 and
1289   later fully support this driver.
1290 
1291 ATEN EH-100 protocol
1292 CONFIG_PARIDE_ATEN
1293   This option enables support for the ATEN EH-100 parallel port IDE
1294   protocol. This protocol is used in some inexpensive low performance
1295   parallel port kits made in Hong Kong. If you chose to build PARIDE
1296   support into your kernel, you may answer Y here to build in the
1297   protocol driver, otherwise you should answer M to build it as a
1298   loadable module. The module will be called aten.o. You must also
1299   have a high-level driver for the type of device that you want to
1300   support.
1301 
1302 MicroSolutions backpack protocol
1303 CONFIG_PARIDE_BPCK
1304   This option enables support for the MicroSolutions backpack parallel
1305   port IDE protocol. If you chose to build PARIDE support into your
1306   kernel, you may answer Y here to build in the protocol driver,
1307   otherwise you should answer M to build it as a loadable module. The
1308   module will be called bpck.o. You must also have a high-level driver
1309   for the type of device that you want to support.
1310 
1311 DataStor Commuter protocol
1312 CONFIG_PARIDE_COMM
1313   This option enables support for the Commuter parallel port IDE 
1314   protocol from DataStor. If you chose to build PARIDE support
1315   into your kernel, you may answer Y here to build in the protocol
1316   driver, otherwise you should answer M to build it as a loadable
1317   module. The module will be called comm.o. You must also have
1318   a high-level driver for the type of device that you want to support.
1319 
1320 DataStor EP-2000 protocol
1321 CONFIG_PARIDE_DSTR
1322   This option enables support for the EP-2000 parallel port IDE 
1323   protocol from DataStor. If you chose to build PARIDE support
1324   into your kernel, you may answer Y here to build in the protocol
1325   driver, otherwise you should answer M to build it as a loadable
1326   module. The module will be called dstr.o. You must also have
1327   a high-level driver for the type of device that you want to support.
1328 
1329 Shuttle EPAT/EPEZ protocol
1330 CONFIG_PARIDE_EPAT
1331   This option enables support for the EPAT parallel port IDE protocol.
1332   EPAT is a parallel port IDE adapter manufactured by Shuttle
1333   Technology and widely used in devices from major vendors such as
1334   Hewlett-Packard, SyQuest, Imation and Avatar. If you chose to build
1335   PARIDE support into your kernel, you may answer Y here to build in
1336   the protocol driver, otherwise you should answer M to build it as a
1337   loadable module. The module will be called epat.o. You must also
1338   have a high-level driver for the type of device that you want to
1339   support.
1340 
1341 Shuttle EPIA protocol
1342 CONFIG_PARIDE_EPIA
1343   This option enables support for the (obsolete) EPIA parallel port
1344   IDE protocol from Shuttle Technology. This adapter can still be
1345   found in some no-name kits. If you chose to build PARIDE support
1346   into your kernel, you may answer Y here to build in the protocol
1347   driver, otherwise you should answer M to build it as a loadable
1348   module. The module will be called epia.o. You must also have a
1349   high-level driver for the type of device that you want to support.
1350 
1351 FIT TD-2000 protocol
1352 CONFIG_PARIDE_FIT2
1353   This option enables support for the TD-2000 parallel port IDE
1354   protocol from Fidelity International Technology. This is a simple
1355   (low speed) adapter that is used in some portable hard drives. If
1356   you chose to build PARIDE support into your kernel, you may answer Y
1357   here to build in the protocol driver, otherwise you should answer M
1358   to build it as a loadable module. The module will be called ktti.o.
1359   You must also have a high-level driver for the type of device that
1360   you want to support.
1361 
1362 FIT TD-3000 protocol
1363 CONFIG_PARIDE_FIT3
1364   This option enables support for the TD-3000 parallel port IDE
1365   protocol from Fidelity International Technology. This protocol is
1366   used in newer models of their portable disk, CD-ROM and PD/CD
1367   devices. If you chose to build PARIDE support into your kernel, you
1368   may answer Y here to build in the protocol driver, otherwise you
1369   should answer M to build it as a loadable module. The module will be
1370   called fit3.o. You must also have a high-level driver for the type
1371   of device that you want to support.
1372 
1373 Freecom IQ ASIC-2 protocol
1374 CONFIG_PARIDE_FRIQ
1375   This option enables support for version 2 of the Freecom IQ parallel
1376   port IDE adapter.  This adapter is used by the Maxell Superdisk 
1377   drive.  If you chose to build PARIDE support into your kernel, you
1378   may answer Y here to build in the protocol driver, otherwise you
1379   should answer M to build it as a loadable module. The module will be
1380   called friq.o. You must also have a high-level driver for the type
1381   of device that you want to support. 
1382 
1383 FreeCom power protocol
1384 CONFIG_PARIDE_FRPW
1385   This option enables support for the Freecom power parallel port IDE
1386   protocol. If you chose to build PARIDE support into your kernel, you
1387   may answer Y here to build in the protocol driver, otherwise you
1388   should answer M to build it as a loadable module. The module will be
1389   called frpw.o. You must also have a high-level driver for the type
1390   of device that you want to support.
1391 
1392 KingByte KBIC-951A/971A protocols
1393 CONFIG_PARIDE_KBIC
1394   This option enables support for the KBIC-951A and KBIC-971A parallel
1395   port IDE protocols from KingByte Information Corp. KingByte's
1396   adapters appear in many no-name portable disk and CD-ROM products,
1397   especially in Europe. If you chose to build PARIDE support into your
1398   kernel, you may answer Y here to build in the protocol driver,
1399   otherwise you should answer M to build it as a loadable module. The
1400   module will be called kbic.o. You must also have a high-level driver
1401   for the type of device that you want to support.
1402 
1403 KT PHd protocol
1404 CONFIG_PARIDE_KTTI
1405   This option enables support for the "PHd" parallel port IDE protocol
1406   from KT Technology. This is a simple (low speed) adapter that is
1407   used in some 2.5" portable hard drives. If you chose to build PARIDE
1408   support into your kernel, you may answer Y here to build in the
1409   protocol driver, otherwise you should answer M to build it as a
1410   loadable module. The module will be called ktti.o. You must also
1411   have a high-level driver for the type of device that you want to
1412   support.
1413 
1414 OnSpec 90c20 protocol
1415 CONFIG_PARIDE_ON20
1416   This option enables support for the (obsolete) 90c20 parallel port 
1417   IDE protocol from OnSpec (often marketed under the ValuStore brand
1418   name). If you chose to build PARIDE support into your kernel, you 
1419   may answer Y here to build in the protocol driver, otherwise you 
1420   should answer M to build it as a loadable module. The module will 
1421   be called on20.o. You must also have a high-level driver for the 
1422   type of device that you want to support.
1423 
1424 OnSpec 90c26 protocol
1425 CONFIG_PARIDE_ON26
1426   This option enables support for the 90c26 parallel port IDE protocol
1427   from OnSpec Electronics (often marketed under the ValuStore brand
1428   name). If you chose to build PARIDE support into your kernel, you
1429   may answer Y here to build in the protocol driver, otherwise you
1430   should answer M to build it as a loadable module. The module will be
1431   called on26.o. You must also have a high-level driver for the type
1432   of device that you want to support.
1433 
1434 Logical Volume Manager (LVM) support
1435 CONFIG_BLK_DEV_LVM
1436   This driver lets you combine several hard disks, hard disk
1437   partitions, multiple devices or even loop devices (for evaluation
1438   purposes) into a volume group.  Imagine a volume group as a kind of
1439   virtual disk. Logical volumes, which can be thought of as virtual
1440   partitions, can be created in the volume group.  You can resize
1441   volume groups and logical volumes after creation time, corresponding
1442   to new capacity needs.  Logical volumes are accessed as block
1443   devices named /dev/VolumeGroupName/LogicalVolumeName.
1444 
1445   For details see Documentation/LVM-HOWTO. You will need supporting
1446   user space software; location is in Documentation/Changes.
1447 
1448   If you want to compile this support as a module ( = code which can
1449   be inserted in and removed from the running kernel whenever you
1450   want), say M here and read Documentation/modules.txt. The module
1451   will be called lvm-mod.o.
1452 
1453 Logical Volume Manager /proc file system information
1454 CONFIG_LVM_PROC_FS
1455   If you say Y here, you are able to access overall Logical Volume
1456   Manager, Volume Group, Logical and Physical Volume information in
1457   /proc/lvm.
1458 
1459   To use this option, you have to check, that the "/proc file system
1460   support" (CONFIG_PROC_FS) is enabled too.
1461 
1462 Multiple devices driver support
1463 CONFIG_BLK_DEV_MD
1464   This driver lets you combine several hard disk partitions into one
1465   logical block device. This can be used to simply append one
1466   partition to another one or to combine several redundant hard disks
1467   into a RAID1/4/5 device so as to provide protection against hard
1468   disk failures. This is called "Software RAID" since the combining of
1469   the partitions is done by the kernel. "Hardware RAID" means that the
1470   combining is done by a dedicated controller; if you have such a
1471   controller, you do not need to say Y here.
1472 
1473   More information about Software RAID on Linux is contained in the
1474   Software-RAID mini-HOWTO, available from
1475   http://www.linuxdoc.org/docs.html#howto . There you will also
1476   learn where to get the supporting user space utilities raidtools.
1477 
1478   If unsure, say N.
1479 
1480 Linear (append) mode
1481 CONFIG_MD_LINEAR
1482   If you say Y here, then your multiple devices driver will be able to
1483   use the so-called linear mode, i.e. it will combine the hard disk
1484   partitions by simply appending one to the other. 
1485 
1486   If you want to compile this as a module ( = code which can be
1487   inserted in and removed from the running kernel whenever you want),
1488   say M here and read Documentation/modules.txt. The module will be
1489   called linear.o.
1490 
1491   If unsure, say Y.
1492 
1493 RAID-0 (striping) mode
1494 CONFIG_MD_RAID0
1495   If you say Y here, then your multiple devices driver will be able to
1496   use the so-called raid0 mode, i.e. it will combine the hard disk
1497   partitions into one logical device in such a fashion as to fill them
1498   up evenly, one chunk here and one chunk there. This will increase
1499   the throughput rate if the partitions reside on distinct disks. 
1500 
1501   Information about Software RAID on Linux is contained in the
1502   Software-RAID mini-HOWTO, available from
1503   http://www.linuxdoc.org/docs.html#howto . There you will also
1504   learn where to get the supporting user space utilities raidtools.
1505 
1506   If you want to compile this as a module ( = code which can be
1507   inserted in and removed from the running kernel whenever you want),
1508   say M here and read Documentation/modules.txt. The module will be
1509   called raid0.o.
1510 
1511   If unsure, say Y.
1512 
1513 RAID-1/RAID-5 code (DANGEROUS)
1514 CONFIG_RAID15_DANGEROUS
1515   This new RAID1/RAID5 code has been freshly merged, and has not seen
1516   enough testing yet. While there are no known bugs in it, it might
1517   destroy your filesystems, eat your data and start World War III.
1518   You have been warned.
1519 
1520   If unsure, say N.
1521 
1522 RAID-1 (mirroring) mode
1523 CONFIG_MD_RAID1
1524   A RAID-1 set consists of several disk drives which are exact copies
1525   of each other. In the event of a mirror failure, the RAID driver
1526   will continue to use the operational mirrors in the set, providing
1527   an error free MD (multiple device) to the higher levels of the
1528   kernel. In a set with N drives, the available space is the capacity
1529   of a single drive, and the set protects against a failure of (N - 1)
1530   drives. 
1531 
1532   Information about Software RAID on Linux is contained in the
1533   Software-RAID mini-HOWTO, available from
1534   http://www.linuxdoc.org/docs.html#howto . There you will also
1535   learn where to get the supporting user space utilities raidtools.
1536 
1537   If you want to use such a RAID-1 set, say Y. This code is also
1538   available as a module called raid1.o ( = code which can be inserted
1539   in and removed from the running kernel whenever you want). If you
1540   want to compile it as a module, say M here and read
1541   Documentation/modules.txt.
1542 
1543   If unsure, say Y.
1544 
1545 RAID-4/RAID-5 mode
1546 CONFIG_MD_RAID5
1547   A RAID-5 set of N drives with a capacity of C MB per drive provides
1548   the capacity of C * (N - 1) MB, and protects against a failure
1549   of a single drive. For a given sector (row) number, (N - 1) drives
1550   contain data sectors, and one drive contains the parity protection.
1551   For a RAID-4 set, the parity blocks are present on a single drive,
1552   while a RAID-5 set distributes the parity across the drives in one
1553   of the available parity distribution methods.
1554 
1555   Information about Software RAID on Linux is contained in the
1556   Software-RAID mini-HOWTO, available from
1557   http://www.linuxdoc.org/docs.html#howto . There you will also
1558   learn where to get the supporting user space utilities raidtools.
1559 
1560   If you want to use such a RAID-4/RAID-5 set, say Y. This code is
1561   also available as a module called raid5.o ( = code which can be
1562   inserted in and removed from the running kernel whenever you want).
1563   If you want to compile it as a module, say M here and read
1564   Documentation/modules.txt.
1565 
1566   If unsure, say Y.
1567 
1568 RAID Boot support
1569 CONFIG_MD_BOOT
1570   To boot with an initial raid volume (any type) you can select
1571   autodetect, or answer Y here and appropriate options to the kernel
1572   at boot time.
1573   For lilo and loadlin options see the file Documentation/md.txt.
1574 
1575 RAID AutoDetect support
1576 CONFIG_AUTODETECT_RAID
1577   An alternative to "Raid Boot support" is autodetect support.
1578   With this selected, any partitons of type 0xFD will be considered for
1579   inclusion in a RAID array.  Information in the RAID-superblock on
1580   the partition will determine how it is included.
1581 
1582 Support for Acer PICA 1 chipset
1583 CONFIG_ACER_PICA_61
1584   This is a machine with a R4400 133/150 MHz CPU. To compile a Linux
1585   kernel that runs on these, say Y here. For details about Linux on
1586   the MIPS architecture, check out the Linux/MIPS FAQ on the WWW at
1587   http://oss.sgi.com/mips .
1588 
1589 Support for Algorithmics P4032 (EXPERIMENTAL)
1590 CONFIG_ALGOR_P4032
1591   This is an evaluation board of the British company Algorithmics. The
1592   board uses the R4300 and a R5230 CPUs. For more information about
1593   this board see http://www.algor.co.uk .
1594 
1595 Support for BAGET MIPS series
1596 CONFIG_BAGET_MIPS
1597   This enables support for the Baget, a Russian embedded system.  For 
1598   more details about the Baget see the Linux/MIPS FAQ on 
1599   http://oss.sgi.com/mips .
1600 
1601 Support for Cobalt Microserver
1602 CONFIG_COBALT_MICRO_SERVER
1603   This enables support for the Cobalt Microserver.  For more information
1604   see the Linux/MIPS FAQ on http://oss.sgi.com/mips .
1605 
1606 Support for 2800
1607 CONFIG_COBALT_28
1608   This adds support for the Cobalt Microserver 2800.  A kernel with this
1609   option selected will only work on the 2800.
1610 
1611 Support for DECstations
1612 CONFIG_DECSTATION
1613   This enables support for DEC's MIPS based workstations.  For details
1614   see the Linux/MIPS FAQ on http://oss.sgi.com/mips and the 
1615   DECstation porting pages on http://decstation.unix-ag.org .
1616 
1617   If you have one of the following DECstation Models you definitely
1618   want to choose R4xx0 for the CPU Type:
1619 
1620         DECstation 5000/50
1621         DECstation 5000/150
1622         DECstation 5000/260
1623         DECsystem 5900/260
1624 
1625   otherwise choose R3000.
1626 
1627 Support for NEC DDB Vrc-5074
1628 CONFIG_DDB5074
1629   This enables support for the VR5000-based NEC DDB Vrc-5074
1630   evaluation board.
1631 
1632 Support for Mips Magnum 4000
1633 CONFIG_MIPS_MAGNUM_4000
1634   This is a machine with a R4000 100 MHz CPU. To compile a Linux
1635   kernel that runs on these, say Y here. For details about Linux on
1636   the MIPS architecture, check out the Linux/MIPS FAQ on the WWW at
1637   http://oss.sgi.com/mips.
1638 
1639 Support for Olivetti M700
1640 CONFIG_OLIVETTI_M700
1641   This is a machine with a R4000 100 MHz CPU. To compile a Linux
1642   kernel that runs on these, say Y here. For details about Linux on
1643   the MIPS architecture, check out the Linux/MIPS FAQ on the WWW at
1644   http://oss.sgi.com/mips.
1645 
1646 Support for SGI IP22
1647 CONFIG_SGI_IP22
1648   This are the SGI Indy, Challenge S and Indigo2, as well as certain
1649   OEM variants like the Tandem CMN B006S. To compile a Linux kernel
1650   that runs on these, say Y here.
1651 
1652 Support for SGI IP27
1653   This are the SGI Origin 200, Origin 2000 and Onyx 2 Graphics
1654   workstations.  To compile a Linux kernel that runs on these, say Y
1655   here.
1656 
1657 IP27 N-Mode
1658 CONFIG_SGI_SN0_N_MODE
1659   The nodes of Origin 200, Origin 2000 and Onyx 2 systems can be
1660   configured in either N-Modes which allows for more nodes or M-Mode
1661   which allows for more more memory.  Your system is most probably
1662   running in M-Mode, so you should say N here.
1663 
1664 MIPS JAZZ onboard SONIC Ethernet support
1665 CONFIG_MIPS_JAZZ_SONIC
1666   This is the driver for the onboard card of of MIPS Magnum 4000,
1667   Acer PICA, Olivetti M700-10 and a few other identical OEM systems.
1668 
1669 MIPS JAZZ FAS216 SCSI support
1670 CONFIG_JAZZ_ESP
1671   This is the driver for the onboard SCSI host adapter of MIPS Magnum
1672   4000, Acer PICA, Olivetti M700-10 and a few other identical OEM
1673   systems.
1674 
1675 PCMCIA SCSI adapter support
1676 CONFIG_SCSI_PCMCIA
1677   Say Y here if you intend to attach a PCMCIA or CardBus card to your
1678   computer which acts as a SCSI host adapter. These are credit card
1679   size devices often used with laptops.
1680 
1681   Note that the answer to this question won't directly affect the
1682   kernel: saying N will just cause this configure script to skip all
1683   the questions PCMCIA SCSI host adapters.
1684 
1685 Adaptec AHA152X PCMCIA support
1686 CONFIG_PCMCIA_AHA152X
1687   Say Y here if you intend to attach this type of PCMCIA SCSI host
1688   adapter to your computer.
1689 
1690   This driver is also available as a module called aha152x_cs.o ( =
1691   code which can be inserted in and removed from the running kernel
1692   whenever you want). If you want to compile it as a module, say M
1693   here and read Documentation/modules.txt.
1694 
1695 Qlogic PCMCIA support
1696 CONFIG_PCMCIA_QLOGIC
1697   Say Y here if you intend to attach this type of PCMCIA SCSI host
1698   adapter to your computer.
1699 
1700   This driver is also available as a module called qlogic_cs.o ( =
1701   code which can be inserted in and removed from the running kernel
1702   whenever you want). If you want to compile it as a module, say M
1703   here and read Documentation/modules.txt.
1704 
1705 Future Domain PCMCIA support
1706 CONFIG_PCMCIA_FDOMAIN
1707   Say Y here if you intend to attach this type of PCMCIA SCSI host
1708   adapter to your computer.
1709 
1710   This driver is also available as a module called fdomain_cs.o ( =
1711   code which can be inserted in and removed from the running kernel
1712   whenever you want). If you want to compile it as a module, say M
1713   here and read Documentation/modules.txt.
1714 
1715 Adaptec APA1480 CardBus support
1716 CONFIG_PCMCIA_APA1480
1717   Say Y here if you intend to attach this type of CardBus SCSI host
1718   adapter to your computer.
1719 
1720   This driver is also available as a module called apa1480_cb.o ( =
1721   code which can be inserted in and removed from the running kernel
1722   whenever you want). If you want to compile it as a module, say M
1723   here and read Documentation/modules.txt.
1724 
1725 CPU type
1726 CONFIG_CPU_R3000
1727   Please make sure to pick the right CPU type. Linux/MIPS is not
1728   designed to be generic, i.e. Kernels compiled for R3000 CPUs will
1729   *not* work on R4000 Machines and vice versa.
1730   However, since most the supported Machines have an R4000 (or 
1731   similar) CPU, R4xx0 might be a safe bet.
1732   If the resulting Kernel does not work try to recompile with R3000.
1733 
1734 Support for large 64-bit configurations
1735 CONFIG_MIPS_INSANE_LARGE
1736   MIPS R10000 does support a 44 bit / 16TB address space as opposed to
1737   previous 64-bit processors which only supported 40 bit / 1TB. If you
1738   need processes of more than 1TB virtual address space, say Y here.
1739   This will result in additional memory usage, so it is not
1740   recommended for normal users.
1741 
1742 Generate little endian code
1743 CONFIG_CPU_LITTLE_ENDIAN
1744   Some MIPS machines can be configured for either little or big endian
1745   byte order. These modes require different kernels. Say Y if your
1746   machine is little endian, N if it's a big endian machine.
1747 
1748 Networking support
1749 CONFIG_NET
1750   Unless you really know what you are doing, you should say Y here.
1751   The reason is that some programs need kernel networking support even
1752   when running on a stand-alone machine that isn't connected to any
1753   other computer. If you are upgrading from an older kernel, you
1754   should consider updating your networking tools too because changes
1755   in the kernel and the tools often go hand in hand. The tools are
1756   contained in the package net-tools, the location and version number
1757   of which are given in Documentation/Changes.
1758 
1759   For a general introduction to Linux networking, it is highly
1760   recommended to read the NET-3-HOWTO, available from
1761   http://www.linuxdoc.org/docs.html#howto .
1762 
1763 Socket filtering
1764 CONFIG_FILTER
1765   The Linux Socket Filter is derived from the Berkeley Packet Filter.
1766   If you say Y here, user-space programs can attach a filter to any
1767   socket and thereby tell the kernel that it should allow or disallow
1768   certain types of data to get through the socket. Linux Socket
1769   Filtering works on all socket types except TCP for now. See the text
1770   file Documentation/networking/filter.txt for more information.
1771   If unsure, say N.
1772 
1773 Network packet filtering
1774 CONFIG_NETFILTER
1775   Netfilter is a framework for filtering and mangling network packets
1776   that pass through your Linux box.
1777 
1778   The most common use of packet filtering is to run your Linux box as
1779   a firewall protecting a local network from the Internet. The type of
1780   firewall provided by this kernel support is called a "packet
1781   filter", which means that it can reject individual network packets
1782   based on type, source, destination etc. The other kind of firewall,
1783   a "proxy-based" one, is more secure but more intrusive and more
1784   bothersome to set up; it inspects the network traffic much more
1785   closely, modifies it and has knowledge about the higher level
1786   protocols, which a packet filter lacks. Moreover, proxy-based
1787   firewalls often require changes to the programs running on the local
1788   clients. Proxy-based firewalls don't need support by the kernel, but
1789   they are often combined with a packet filter, which only works if
1790   you say Y here.
1791 
1792   You should also say Y here if you intend to use your Linux box as
1793   the gateway to the Internet for a local network of machines without
1794   globally valid IP addresses. This is called "masquerading": if one
1795   of the computers on your local network wants to send something to
1796   the outside, your box can "masquerade" as that computer, i.e. it
1797   forwards the traffic to the intended outside destination, but
1798   modifies the packets to make it look like they came from the
1799   firewall box itself. It works both ways: if the outside host
1800   replies, the Linux box will silently forward the traffic to the
1801   correct local computer. This way, the computers on your local net
1802   are completely invisible to the outside world, even though they can
1803   reach the outside and can receive replies. It is even possible to
1804   run globally visible servers from within a masqueraded local network
1805   using a mechanism called portforwarding. Masquerading is also often
1806   called NAT (Network Address Translation).
1807 
1808   Another use of Netfilter is in transparent proxying: if a machine on
1809   the local network tries to connect to an outside host, your Linux
1810   box can transparently forward the traffic to a local server,
1811   typically a caching proxy server.
1812 
1813   Various modules exist for netfilter which replace the previous
1814   masquerading (ipmasqadm), packet filtering (ipchains), transparent
1815   proxying, and portforwarding mechanisms. Please see
1816   Documentation/Changes under "iptables" for the location of these
1817   packages.
1818  
1819   Make sure to say N to "Fast switching" below if you intend to say Y
1820   here, as Fast switching currently bypasses netfilter.
1821  
1822   Chances are that you should say Y here if you compile a kernel which
1823   will run as a router and N for regular hosts. If unsure, say N.
1824  
1825 Network packet filtering debugging
1826 CONFIG_NETFILTER_DEBUG
1827   You can say Y here if you want to get additional messages useful in
1828   debugging the netfilter code. 
1829 
1830 IP: connection tracking (required for masq/NAT)
1831 CONFIG_IP_NF_CONNTRACK
1832   Connection tracking keeps a record of what packets have passed
1833   through your machine, in order to figure out how they are related
1834   into connections.
1835 
1836   This is required to do Masquerading or other kinds of Network
1837   Address Translation (except for Fast NAT).  It can also be used to
1838   enhance packet filtering (see `Connection state match support'
1839   below).
1840 
1841   If you want to compile it as a module, say M here and read
1842   Documentation/modules.txt.  If unsure, say `N'.
1843 
1844 FTP protocol support
1845 CONFIG_IP_NF_FTP
1846   Tracking FTP connections is problematic: special helpers are
1847   required for tracking them, and doing masquerading and other forms
1848   of Network Address Translation on them.
1849 
1850   If you want to compile it as a module, say M here and read
1851   Documentation/modules.txt.  If unsure, say `Y'.
1852 
1853 IP: user space queueing via NETLINK (EXPERIMENTAL)
1854 CONFIG_IP_NF_QUEUE
1855   Netfilter has the ability to queue packets to user space: the
1856   netlink device can be used to access them using this driver.
1857 
1858   If you want to compile it as a module, say M here and read
1859   Documentation/modules.txt.  If unsure, say `N'.
1860 
1861 IP: ip tables support (required for filtering/masq/NAT)
1862 CONFIG_IP_NF_IPTABLES
1863   iptables is a general, extensible packet identification framework.
1864   The packet filtering and full NAT (masquerading, port forwarding,
1865   etc) subsystems now use this: say `Y' or `M' here if you want to use
1866   either of those.
1867 
1868   If you want to compile it as a module, say M here and read
1869   Documentation/modules.txt.  If unsure, say `N'.
1870 
1871 limit match support
1872 CONFIG_IP_NF_MATCH_LIMIT
1873   limit matching allows you to control the rate at which a rule can be
1874   matched: mainly useful in combination with the LOG target ("LOG
1875   target support", below) and to avoid some Denial of Service attacks.
1876 
1877   If you want to compile it as a module, say M here and read
1878   Documentation/modules.txt.  If unsure, say `N'.
1879 
1880 MAC address match support
1881 CONFIG_IP_NF_MATCH_MAC
1882   mac matching allows you to match packets based on the source
1883   ethernet address of the packet.
1884 
1885   If you want to compile it as a module, say M here and read
1886   Documentation/modules.txt.  If unsure, say `N'.
1887 
1888 netfilter mark match support
1889 CONFIG_IP_NF_MATCH_MARK
1890   Netfilter mark matching allows you to match packets based on the
1891   `nfmark' value in the packet.  This can be set by the MARK target
1892   (see below).
1893 
1894   If you want to compile it as a module, say M here and read
1895   Documentation/modules.txt.  If unsure, say `N'.
1896 
1897 Multiple port match support
1898 CONFIG_IP_NF_MATCH_MULTIPORT
1899   Multiport matching allows you to match TCP or UDP packets based on
1900   a series of source or destination ports: normally a rule can only
1901   match a single range of ports.
1902 
1903   If you want to compile it as a module, say M here and read
1904   Documentation/modules.txt.  If unsure, say `N'.
1905 
1906 TOS match support
1907 CONFIG_IP_NF_MATCH_TOS
1908   TOS matching allows you to match packets based on the Type Of
1909   Service fields of the IP packet.
1910 
1911   If you want to compile it as a module, say M here and read
1912   Documentation/modules.txt.  If unsure, say `N'.
1913 
1914 Connection state match support
1915 CONFIG_IP_NF_MATCH_STATE
1916   Connection state matching allows you to match packets based on their
1917   relationship to a tracked connection (ie. previous packets).  This
1918   is a powerful tool for packet classification.
1919 
1920   If you want to compile it as a module, say M here and read
1921   Documentation/modules.txt.  If unsure, say `N'.
1922 
1923 Unclean match support (EXPERIMENTAL)
1924 CONFIG_IP_NF_MATCH_UNCLEAN
1925   Unclean packet matching matches any strange or invalid packets, by
1926   looking at a series of fields in the IP, TCP, UDP and ICMP headers.
1927 
1928   If you want to compile it as a module, say M here and read
1929   Documentation/modules.txt.  If unsure, say `N'.
1930 
1931 Owner match support (EXPERIMENTAL)
1932 CONFIG_IP_NF_MATCH_OWNER
1933   Packet owner matching allows you to match locally-generated packets
1934   based on who created them: the user, group, process or session.
1935 
1936   If you want to compile it as a module, say M here and read
1937   Documentation/modules.txt.  If unsure, say `N'.
1938 
1939 Packet filtering
1940 CONFIG_IP_NF_FILTER
1941   Packet filtering defines a table `filter', which has a series of
1942   rules for simple packet filtering at local input, forwarding and
1943   local output.  See the man page for iptables(8).
1944 
1945   If you want to compile it as a module, say M here and read
1946   Documentation/modules.txt.  If unsure, say `N'.
1947 
1948 REJECT target support
1949 CONFIG_IP_NF_TARGET_REJECT
1950   The REJECT target allows a filtering rule to specify that an ICMP
1951   error should be issued in response to an incoming packet, rather
1952   than silently being dropped.
1953 
1954   If you want to compile it as a module, say M here and read
1955   Documentation/modules.txt.  If unsure, say `N'.
1956 
1957 MIRROR target support (EXPERIMENTAL)
1958 CONFIG_IP_NF_TARGET_MIRROR
1959   The MIRROR target allows a filtering rule to specify that an
1960   incoming packet should be bounced back to the sender.
1961 
1962   If you want to compile it as a module, say M here and read
1963   Documentation/modules.txt.  If unsure, say `N'.
1964 
1965 Full NAT
1966 CONFIG_IP_NF_NAT
1967   The Full NAT option allows masquerading, port forwarding and other
1968   forms of full Network Address Port Translation.  It is controlled by
1969   the `nat' table in iptables: see the man page for iptables(8).
1970 
1971   If you want to compile it as a module, say M here and read
1972   Documentation/modules.txt.  If unsure, say `N'.
1973 
1974 MASQUERADE target support
1975 CONFIG_IP_NF_TARGET_MASQUERADE
1976   Masquerading is a special case of NAT: all outgoing connections are
1977   changed to seem to come from a particular interface's address, and
1978   if the interface goes down, those connections are lost.  This is
1979   only useful for dialup accounts with dynamic IP address (ie. your IP
1980   address will be different on next dialup).
1981 
1982   If you want to compile it as a module, say M here and read
1983   Documentation/modules.txt.  If unsure, say `N'.
1984 
1985 REDIRECT target support
1986 CONFIG_IP_NF_TARGET_REDIRECT
1987   REDIRECT is a special case of NAT: all incoming connections are
1988   mapped onto the incoming interface's address, causing the packets to
1989   come to the local machine instead of passing through.  This is
1990   useful for transparent proxies.
1991 
1992   If you want to compile it as a module, say M here and read
1993   Documentation/modules.txt.  If unsure, say `N'.
1994 
1995 Packet mangling
1996 CONFIG_IP_NF_MANGLE
1997   This option adds a `mangle' table to iptables: see the man page for
1998   iptables(8).  This table is used for various packet alterations
1999   which can effect how the packet is routed.
2000 
2001   If you want to compile it as a module, say M here and read
2002   Documentation/modules.txt.  If unsure, say `N'.
2003 
2004 TOS target support
2005 CONFIG_IP_NF_TARGET_TOS
2006   This option adds a `TOS' target, which allows you to create rules in
2007   the `mangle' table which alter the Type Of Service field of an IP
2008   packet prior to routing.
2009 
2010   If you want to compile it as a module, say M here and read
2011   Documentation/modules.txt.  If unsure, say `N'.
2012 
2013 MARK target support
2014 CONFIG_IP_NF_TARGET_MARK
2015   This option adds a `MARK' target, which allows you to create rules
2016   in the `mangle' table which alter the netfilter mark (nfmark) field
2017   associated with the packet packet prior to routing. This can change
2018   the routing method (see `IP: use netfilter MARK value as routing
2019   key') and can also be used by other subsystems to change their
2020   behavior.
2021 
2022   If you want to compile it as a module, say M here and read
2023   Documentation/modules.txt.  If unsure, say `N'.
2024 
2025 LOG target support
2026 CONFIG_IP_NF_TARGET_LOG
2027   This option adds a `LOG' target, which allows you to create rules in
2028   any iptables table which records the packet header to the syslog.
2029 
2030   If you want to compile it as a module, say M here and read
2031   Documentation/modules.txt.  If unsure, say `N'.
2032 
2033 ipchains (2.2-style) support
2034 CONFIG_IP_NF_COMPAT_IPCHAINS
2035   This option places ipchains (with masquerading and redirection
2036   support) back into the kernel, using the new netfilter
2037   infrastructure.  It is not recommended for new installations (see
2038   `Packet filtering').  With this enabled, you should be able to use
2039   the ipchains tool exactly as in 2.2 kernels.
2040 
2041   If you want to compile it as a module, say M here and read
2042   Documentation/modules.txt.  If unsure, say `N'.
2043 
2044 ipfwadm (2.0-style) support
2045 CONFIG_IP_NF_COMPAT_IPFWADM
2046   This option places ipfwadm (with masquerading and redirection
2047   support) back into the kernel, using the new netfilter
2048   infrastructure.  It is not recommended for new installations (see
2049   `Packet filtering').  With this enabled, you should be able to use
2050   the ipfwadm tool exactly as in 2.0 kernels.
2051 
2052   If you want to compile it as a module, say M here and read
2053   Documentation/modules.txt.  If unsure, say `N'.
2054 
2055 TCP Explicit Congestion Notification support
2056 CONFIG_INET_ECN
2057   Explicit Congestion Notification (ECN) allows routers to notify
2058   clients about network congestion, resulting in fewer dropped packets
2059   and increased network performance. This option adds ECN support to the
2060   Linux kernel, as well as a sysctl (/proc/sys/net/ipv4/tcp_ecn) which
2061   allows ECN support to be disabled at runtime.
2062 
2063   Note that, on the Internet, there are many broken firewalls which
2064   refuse connections from ECN-enabled machines, and it may be a while
2065   before these firewalls are fixed. Until then, to access a site behind
2066   such a firewall (some of which are major sites, at the time of this
2067   writing) you will have to disable this option, either by saying N now
2068   or by using the sysctl.
2069 
2070   If in doubt, say N.
2071 
2072 SYN flood protection
2073 CONFIG_SYN_COOKIES
2074   Normal TCP/IP networking is open to an attack known as "SYN
2075   flooding". This denial-of-service attack prevents legitimate remote
2076   users from being able to connect to your computer during an ongoing
2077   attack and requires very little work from the attacker, who can
2078   operate from anywhere on the Internet.
2079 
2080   SYN cookies provide protection against this type of attack. If you
2081   say Y here, the TCP/IP stack will use a cryptographic challenge
2082   protocol known as "SYN cookies" to enable legitimate users to
2083   continue to connect, even when your machine is under attack. There
2084   is no need for the legitimate users to change their TCP/IP software;
2085   SYN cookies work transparently to them. For technical information
2086   about SYN cookies, check out
2087   ftp://koobera.math.uic.edu/syncookies.html .
2088 
2089   If you are SYN flooded, the source address reported by the kernel is
2090   likely to have been forged by the attacker; it is only reported as
2091   an aid in tracing the packets to their actual source and should not
2092   be taken as absolute truth.
2093 
2094   SYN cookies may prevent correct error reporting on clients when the
2095   server is really overloaded. If this happens frequently better turn
2096   them off.
2097 
2098   If you say Y here, note that SYN cookies aren't enabled by default;
2099   you can enable them by saying Y to "/proc file system support" and
2100   "Sysctl support" below and executing the command
2101 
2102     echo 1 >/proc/sys/net/ipv4/tcp_syncookies 
2103 
2104   at boot time after the /proc file system has been mounted.
2105   
2106   If unsure, say Y.
2107 
2108 Alpha system type
2109 CONFIG_ALPHA_GENERIC
2110   This is the system type of your hardware.  A "generic" kernel will
2111   run on any supported Alpha system. However, if you configure a
2112   kernel for your specific system, it will be faster and smaller.
2113 
2114   To find out what type of Alpha system you have, you may want to
2115   check out the Linux/Alpha FAQ, accessible on the WWW from
2116   http://www.alphalinux.org . In summary:
2117 
2118   Alcor/Alpha-XLT     AS 600
2119   Alpha-XL            XL-233, XL-266
2120   AlphaBook1          Alpha laptop
2121   Avanti              AS 200, AS 205, AS 250, AS 255, AS 300, AS 400
2122   Cabriolet           AlphaPC64, AlphaPCI64
2123   DP264               DP264
2124   EB164               EB164 21164 evaluation board
2125   EB64+               EB64+ 21064 evaluation board
2126   EB66                EB66 21066 evaluation board
2127   EB66+               EB66+ 21066 evaluation board
2128   Jensen              DECpc 150, DEC 2000 model 300, 
2129                       DEC 2000 model 500
2130   LX164               AlphaPC164-LX
2131   Miata               Personal Workstation 433a, 433au, 500a,
2132                       500au, 600a, or 600au
2133   Mikasa              AS 1000
2134   Noname              AXPpci33, UDB (Multia)
2135   Noritake            AS 1000A, AS 600A, AS 800
2136   PC164               AlphaPC164
2137   Rawhide             AS 1200, AS 4000, AS 4100
2138   Ruffian             RPX164-2, AlphaPC164-UX, AlphaPC164-BX
2139   SX164               AlphaPC164-SX
2140   Sable               AS 2000, AS 2100
2141   Takara              Takara
2142   Titan               Privateer
2143   Wildfire            AlphaServer GS 40/80/160/320
2144 
2145   If you don't know what to do, choose "generic".
2146 
2147 EV5 CPU daughtercard
2148 CONFIG_ALPHA_PRIMO
2149   Say Y if you have an AS 1000 5/xxx or an AS 1000A 5/xxx.
2150 
2151 EV5 CPU(s)
2152 CONFIG_ALPHA_GAMMA
2153   Say Y if you have an AS 2000 5/xxx or an AS 2100 5/xxx.
2154 
2155 Using SRM as bootloader
2156 CONFIG_ALPHA_SRM
2157   There are two different types of booting firmware on Alphas: SRM,
2158   which is command line driven, and ARC, which uses menus and arrow
2159   keys. Details about the Linux/Alpha booting process are contained in
2160   the Linux/Alpha FAQ, accessible on the WWW from
2161   http://www.alphalinux.org .
2162 
2163   The usual way to load Linux on an Alpha machine is to use MILO
2164   (a bootloader that lets you pass command line parameters to the
2165   kernel just like lilo does for the x86 architecture) which can be
2166   loaded either from ARC or can be installed directly as a permanent
2167   firmware replacement from floppy (which requires changing a certain
2168   jumper on the motherboard). If you want to do either of these, say N
2169   here. If MILO doesn't work on your system (true for Jensen
2170   motherboards), you can bypass it altogether and boot Linux directly
2171   from an SRM console; say Y here in order to do that. Note that you
2172   won't be able to boot from an IDE disk using SRM. 
2173 
2174   If unsure, say N.
2175 
2176 Legacy kernel start address
2177 CONFIG_ALPHA_LEGACY_START_ADDRESS
2178   The 2.4 kernel changed the kernel start address from 0x310000
2179   to 0x810000 to make room for the Wildfire's larger SRM console.
2180 
2181   If you're using aboot 0.7 or later, the bootloader will examine
2182   the ELF headers to determine where to transfer control.  Unfortunately,
2183   most older bootloaders -- APB or MILO -- hardcoded the kernel
2184   start address rather than examining the ELF headers, and the result
2185   is a hard lockup.
2186 
2187   Say Y if you have a broken bootloader.  Say N if you do not, or
2188   if you wish to run on Wildfire.
2189 
2190 Large VMALLOC support
2191 CONFIG_ALPHA_LARGE_VMALLOC
2192   Process creation and other aspects of virtual memory management
2193   can be streamlined if we restrict the kernel to one PGD for all
2194   vmalloc allocations.  This equates to about 8GB.
2195 
2196   Under normal circumstances, this is so far and above what is needed
2197   as to be laughable.  However, there are certain applications (such
2198   as benchmark-grade in-kernel web serving) that can make use of as
2199   much vmalloc space as is available.
2200 
2201   Say N unless you know you need gobs and gobs of vmalloc space.
2202 
2203 Non-standard serial port support
2204 CONFIG_SERIAL_NONSTANDARD
2205   Say Y here if you have any non-standard serial boards -- boards
2206   which aren't supported using the standard "dumb" serial driver.
2207   This includes intelligent serial boards such as Cyclades,
2208   Digiboards, etc. These are usually used for systems that need many
2209   serial ports because they serve many terminals or dial-in
2210   connections. 
2211 
2212   Note that the answer to this question won't directly affect the
2213   kernel: saying N will just cause this configure script to skip all
2214   the questions about non-standard serial boards. 
2215 
2216   Most people can say N here.
2217 
2218 Extended dumb serial driver options
2219 CONFIG_SERIAL_EXTENDED
2220   If you wish to use any non-standard features of the standard "dumb"
2221   driver, say Y here. This includes HUB6 support, shared serial
2222   interrupts, special multiport support, support for more than the
2223   four COM 1/2/3/4 boards, etc. 
2224 
2225   Note that the answer to this question won't directly affect the
2226   kernel: saying N will just cause this configure script to skip all
2227   the questions about serial driver options. If unsure, say N.
2228 
2229 Support more than 4 serial ports
2230 CONFIG_SERIAL_MANY_PORTS
2231   Say Y here if you have dumb serial boards other than the four
2232   standard COM 1/2/3/4 ports. This may happen if you have an AST
2233   FourPort, Accent Async, Boca (read the Boca mini-HOWTO, available
2234   from http://www.linuxdoc.org/docs.html#howto ), or other custom
2235   serial port hardware which acts similar to standard serial port
2236   hardware. If you only use the standard COM 1/2/3/4 ports, you can
2237   say N here to save some memory. You can also say Y if you have an
2238   "intelligent" multiport card such as Cyclades, Digiboards, etc.
2239 
2240 Support for sharing serial interrupts
2241 CONFIG_SERIAL_SHARE_IRQ
2242   Some serial boards have hardware support which allows multiple dumb
2243   serial ports on the same board to share a single IRQ. To enable
2244   support for this in the serial driver, say Y here.
2245 
2246 Auto detect IRQ on standard ports (unsafe)
2247 CONFIG_SERIAL_DETECT_IRQ
2248   Say Y here if you want the kernel to try to guess which IRQ
2249   to use for your serial port. 
2250 
2251   This is considered unsafe; it is far better to configure the IRQ in
2252   a boot script using the setserial command.
2253 
2254   If unsure, say N.
2255 
2256 Support special multiport boards
2257 CONFIG_SERIAL_MULTIPORT
2258   Some multiport serial ports have special ports which are used to
2259   signal when there are any serial ports on the board which need
2260   servicing. Say Y here to enable the serial driver to take advantage
2261   of those special I/O ports.
2262 
2263 SGI PROM Console Support
2264 CONFIG_SGI_PROM_CONSOLE
2265   Say Y here if you want to use the PROMs for console I/O.
2266 
2267 SGI Zilog85C30 serial support
2268 CONFIG_SGI_SERIAL
2269   If you want to use your SGI's built-in serial ports under Linux,
2270   answer Y.
2271 
2272 SGI Newport Graphics support (EXPERIMENTAL)
2273 CONFIG_SGI_NEWPORT_GFX
2274   If you have an SGI machine and you want to compile the graphics
2275   drivers, say Y here. This will include the code for the
2276   /dev/graphics and /dev/gfx drivers into the kernel for supporting
2277   virtualized access to your graphics hardware.
2278 
2279 SGI Newport Console support
2280 CONFIG_SGI_NEWPORT_CONSOLE
2281   Say Y here if you want the console on the Newport aka XL graphics
2282   card of your Indy.  Most people say Y here.
2283 
2284 SGI DS1286 RTC support
2285 CONFIG_SGI_DS1286
2286   If you say Y here and create a character special file /dev/rtc with
2287   major number 10 and minor number 135 using mknod ("man mknod"), you
2288   will get access to the real time clock built into your computer.
2289   Every SGI has such a clock built in. It reports status information
2290   via the file /proc/rtc and its behaviour is set by various ioctls on
2291   /dev/rtc.
2292 
2293 Support the Bell Technologies HUB6 card
2294 CONFIG_HUB6
2295   Say Y here to enable support in the dumb serial driver to support
2296   the HUB6 card.
2297 
2298 PCMCIA serial device support
2299 CONFIG_PCMCIA_SERIAL_CS
2300   Say Y here to enable support for 16-bit PCMCIA serial devices,
2301   including serial port cards, modems, and the modem functions of
2302   multi-function ethernet/modem cards. (PCMCIA- or PC-cards are
2303   credit-card size devices often used with laptops.)
2304 
2305   This driver is also available as a module ( = code which can be
2306   inserted in and removed from the running kernel whenever you want).
2307   The module will be called serial_cs.o. If you want to compile it as
2308   a module, say M here and read Documentation/modules.txt. If unsure,
2309   say N.
2310 
2311 CardBus serial device support
2312 CONFIG_PCMCIA_SERIAL_CB
2313   Say Y here to enable support for CardBus serial devices, including
2314   serial port cards, modems, and the modem functions of multi-function
2315   ethernet/modem devices. (CardBus cards are the newer and better 
2316   version of PCMCIA- or PC-cards: credit card size devices often 
2317   used with laptops.)
2318 
2319   This driver is also available as a module ( = code which can be
2320   inserted in and removed from the running kernel whenever you want).
2321   The module will be called serial_cb.o. If you want to compile it as
2322   a module, say M here and read Documentation/modules.txt. If unsure,
2323   say N.
2324 
2325 /dev/agpgart (AGP Support) (EXPERIMENTAL)
2326 CONFIG_AGP
2327   AGP (Accelerated Graphics Port) is a bus system mainly used to
2328   connect graphics cards to the rest of the system. 
2329 
2330   If you have an AGP system and you say Y here, it will be possible to
2331   use the AGP features of your 3D rendering video card. This code acts
2332   as a sort of "AGP driver" for the motherboard's chipset. The glx
2333   module will then be able to program the GART (graphics aperture
2334   relocation table) registers with appropriate values to transfer
2335   commands to the card.
2336 
2337   If you need more texture memory than you can get with the AGP GART
2338   (theoretically up to 256 MB, but in practice usually 64 or 128 MB
2339   due to kernel allocation issues), you could use PCI accesses
2340   and have up to a couple gigs of texture space.
2341 
2342   Note that this is the only means to have XFree4/GLX use
2343   write-combining with MTRR support on the AGP bus. Without it, OpenGL
2344   direct rendering will be a lot slower but still faster than PIO.
2345 
2346   For the moment, you should probably say N, unless you want to test
2347   the GLX component for XFree86 3.3.6, which can be downloaded from
2348   http://utah-glx.sourceforge.net/ , or need to use the 810 Xserver in
2349   XFree 3.3.6.
2350 
2351   This driver is available as a module. If you want to compile it as a
2352   module, say M here and read Documentation/modules.txt. The module
2353   will be called agpgart.o.
2354 
2355 Intel 440LX/BX/GX/815/840/850 support
2356 CONFIG_AGP_INTEL
2357   This option gives you AGP support for the GLX component of the
2358   XFree86 4.x on Intel 440LX/BX/GX, 815, 840 and 850 chipsets.
2359 
2360   For the moment, you should probably say N, unless you want to test
2361   the GLX component for XFree86 3.3.6, which can be downloaded from
2362   http://utah-glx.sourceforge.net/ .
2363 
2364 Intel I810/I810 DC100/I810e support
2365 CONFIG_AGP_I810
2366   This option gives you AGP support for the Xserver on the Intel 810
2367   and 815 chipset boards for their on-board integrated graphics. This
2368   is required to do any useful video modes with these boards.
2369 
2370 VIA chipset support
2371 CONFIG_AGP_VIA
2372   This option gives you AGP support for the GLX component of the
2373   XFree86 4.x on VIA MPV3/Apollo Pro chipsets.
2374 
2375   For the moment, you should probably say N, unless you want to test
2376   the GLX component for XFree86 3.3.6, which can be downloaded from
2377   http://utah-glx.sourceforge.net/ .
2378 
2379 AMD Irongate support
2380 CONFIG_AGP_AMD
2381   This option gives you AGP support for the GLX component of the
2382   XFree86 4.x on AMD Irongate chipset.
2383 
2384   For the moment, you should probably say N, unless you want to test
2385   the GLX component for XFree86 3.3.6, which can be downloaded from
2386   http://utah-glx.sourceforge.net/ .
2387 
2388 Generic SiS support
2389 CONFIG_AGP_SIS
2390   This option gives you AGP support for the GLX component of the "soon
2391   to be released" XFree86 4.x on Silicon Integrated Systems [SiS]
2392   chipsets.
2393 
2394   Note that 5591/5592 AGP chipsets are NOT supported.
2395 
2396   For the moment, you should probably say N, unless you want to test
2397   the GLX component for XFree86 3.3.6, which can be downloaded from
2398   http://utah-glx.sourceforge.net/ .
2399 
2400 ALI M1541 support
2401 CONFIG_AGP_ALI
2402   This option gives you AGP support for the GLX component of the
2403   XFree86 4.x on the ALi M1541 chipset.
2404 
2405   This chipset can do AGP 1x and 2x, but note that there is an
2406   acknowledged incompatibility with Matrox G200 cards. Due to
2407   timing issues, this chipset cannot do AGP 2x with the G200.
2408   This is a hardware limitation. AGP 1x seems to be fine, though.
2409 
2410   For the moment, you should probably say N, unless you want to test
2411   the GLX component for XFree86 3.3.6, which can be downloaded from
2412   http://utah-glx.sourceforge.net/ .
2413 
2414 PCI support
2415 CONFIG_PCI
2416   Find out whether you have a PCI motherboard. PCI is the name of a
2417   bus system, i.e. the way the CPU talks to the other stuff inside
2418   your box. Other bus systems are ISA, EISA, Microchannel (MCA) or
2419   VESA. If you have PCI, say Y, otherwise N. 
2420 
2421   The PCI-HOWTO, available from
2422   http://www.linuxdoc.org/docs.html#howto , contains valuable
2423   information about which PCI hardware does work under Linux and which
2424   doesn't.
2425 
2426 PCI support
2427 CONFIG_PCI_INTEGRATOR
2428   Find out whether you have a PCI motherboard. PCI is the name of a
2429   bus system, i.e. the way the CPU talks to the other stuff inside
2430   your box. Other bus systems are ISA, EISA, Microchannel (MCA) or
2431   VESA. If you have PCI, say Y, otherwise N. 
2432 
2433   The PCI-HOWTO, available from
2434   http://www.linuxdoc.org/docs.html#howto , contains valuable
2435   information about which PCI hardware does work under Linux and which
2436   doesn't.
2437 
2438 QSpan PCI
2439 CONFIG_PCI_QSPAN
2440   Find out whether you have a PCI motherboard. PCI is the name of a
2441   bus system, i.e. the way the CPU talks to the other stuff inside
2442   your box. Other bus systems are ISA, EISA, Microchannel (MCA) or
2443   VESA. If you have PCI, say Y, otherwise N. 
2444 
2445   The PCI-HOWTO, available from
2446   http://www.linuxdoc.org/docs.html#howto , contains valuable
2447   information about which PCI hardware does work under Linux and which
2448   doesn't.
2449 
2450 PCI access mode
2451 CONFIG_PCI_GOBIOS
2452   On PCI systems, the BIOS can be used to detect the PCI devices and
2453   determine their configuration. However, some old PCI motherboards
2454   have BIOS bugs and may crash if this is done. Also, some embedded
2455   PCI-based systems don't have any BIOS at all. Linux can also try to
2456   detect the PCI hardware directly without using the BIOS.
2457 
2458   With this option, you can specify how Linux should detect the PCI
2459   devices. If you choose "BIOS", the BIOS will be used, if you choose
2460   "Direct", the BIOS won't be used, and if you choose "Any", the
2461   kernel will try the direct access method and falls back to the BIOS
2462   if that doesn't work. If unsure, go with the default, which is
2463   "Any".
2464 
2465 PCI device name database
2466 CONFIG_PCI_NAMES
2467   By default, the kernel contains a database of all known PCI device
2468   names to make the information in /proc/pci, /proc/ioports and
2469   similar files comprehensible to the user. This database increases
2470   size of the kernel image by about 80KB, but it gets freed after the
2471   system boots up, so it doesn't take up kernel memory. Anyway, if you
2472   are building an installation floppy or kernel for an embedded system
2473   where kernel image size really matters, you can disable this feature
2474   and you'll get device ID numbers instead of names.
2475 
2476   When in doubt, say Y.
2477 
2478 MCA support
2479 CONFIG_MCA
2480   MicroChannel Architecture is found in some IBM PS/2 machines and
2481   laptops. It is a bus system similar to PCI or ISA. See
2482   Documentation/mca.txt (and especially the web page given there)
2483   before attempting to build an MCA bus kernel.
2484 
2485 EISA support
2486 CONFIG_EISA
2487   The Extended Industry Standard Architecture (EISA) bus was
2488   developed as an open alternative to the IBM MicroChannel bus.
2489 
2490   The EISA bus provided some of the features of the IBM MicroChannel
2491   bus while maintaining backward compatibility with cards made for
2492   the older ISA bus. The EISA bus saw limited use between 1988 and 1995
2493   when it was made obsolete by the PCI bus.
2494 
2495   Say Y here if you are building a kernel for an EISA-based machine.
2496 
2497   Otherwise, say N.
2498 
2499 SGI Visual Workstation support
2500 CONFIG_VISWS
2501   The SGI Visual Workstation series is an IA32-based workstation
2502   based on SGI systems chips with some legacy PC hardware attached.
2503   Say Y here to create a kernel to run on the SGI 320 or 540.
2504   A kernel compiled for the Visual Workstation will not run on other
2505   PC boards and vice versa.
2506   See Documentation/sgi-visws.txt for more.
2507 
2508 SGI Visual Workstation framebuffer support
2509 CONFIG_FB_SGIVW
2510   SGI Visual Workstation support for framebuffer graphics.
2511 
2512 I2O support
2513 CONFIG_I2O
2514   The Intelligent Input/Output (I2O) architecture allows hardware
2515   drivers to be split into two parts: an operating system specific
2516   module called the OSM and an hardware specific module called the
2517   HDM. The OSM can talk to a whole range of HDM's, and ideally the
2518   HDM's are not OS dependent. This allows for the same HDM driver to
2519   be used under different operating systems if the relevant OSM is in
2520   place. In order for this to work, you need to have an I2O interface
2521   adapter card in your computer. This card contains a special I/O
2522   processor (IOP), thus allowing high speeds since the CPU does not
2523   have to deal with I/O.
2524 
2525   If you say Y here, you will get a choice of interface adapter
2526   drivers and OSM's with the following questions.
2527 
2528   This support is also available as a module ( = code which can be
2529   inserted in and removed from the running kernel whenever you want).
2530   If you want to compile it as a module, say M here and read
2531   Documentation/modules.txt. You will get modules called i2o_core.o
2532   and i20_config.o. 
2533 
2534   If unsure, say N.
2535 
2536 I2O PCI support
2537 CONFIG_I2O_PCI
2538   Say Y for support of PCI bus I2O interface adapters. Currently this
2539   is the only variety supported, so you should say Y.
2540 
2541   This support is also available as a module called i2o_pci.o ( = code
2542   which can be inserted in and removed from the running kernel
2543   whenever you want). If you want to compile it as a module, say M
2544   here and read Documentation/modules.txt.
2545 
2546 I2O Block OSM
2547 CONFIG_I2O_BLOCK
2548   Include support for the I2O Block OSM. The Block OSM presents disk
2549   and other structured block devices to the operating system.
2550 
2551   This support is also available as a module called i2o_block.o ( =
2552   code which can be inserted in and removed from the running kernel
2553   whenever you want). If you want to compile it as a module, say M
2554   here and read Documentation/modules.txt.
2555 
2556 I2O LAN OSM
2557 CONFIG_I2O_LAN
2558   Include support for the LAN OSM. You will also need to include
2559   support for token ring or FDDI if you wish to use token ring or FDDI
2560   I2O cards with this driver.
2561 
2562   This support is also available as a module called i2o_lan.o ( = code
2563   which can be inserted in and removed from the running kernel
2564   whenever you want). If you want to compile it as a module, say M
2565   here and read Documentation/modules.txt.
2566 
2567 I2O SCSI OSM
2568 CONFIG_I2O_SCSI
2569   Allows direct SCSI access to SCSI devices on a SCSI or FibreChannel
2570   I2O controller. You can use both the SCSI and Block OSM together if
2571   you wish.
2572 
2573   This support is also available as a module called i2o_scsi.o ( =
2574   code which can be inserted in and removed from the running kernel
2575   whenever you want). If you want to compile it as a module, say M
2576   here and read Documentation/modules.txt.
2577 
2578 I2O /proc support
2579 CONFIG_I2O_PROC
2580   If you say Y here and to "/proc file system support", you will be
2581   able to read I2O related information from the virtual directory
2582   /proc/i2o.
2583 
2584   This support is also available as a module called i2o_proc.o ( =
2585   code which can be inserted in and removed from the running kernel
2586   whenever you want). If you want to compile it as a module, say M
2587   here and read Documentation/modules.txt.
2588 
2589 Plug and Play support
2590 CONFIG_PNP
2591   Plug and Play (PnP) is a standard for peripherals which allows those
2592   peripherals to be configured by software, e.g. assign IRQ's or other
2593   parameters. No jumpers on the cards are needed, instead the values
2594   are provided to the cards from the BIOS, from the operating system,
2595   or using a user-space utility.
2596 
2597   Say Y here if you would like Linux to configure your Plug and Play
2598   devices. You should then also say Y to "ISA Plug and Play support",
2599   below. Alternatively, you can say N here and configure your PnP 
2600   devices using the user space utilities contained in the isapnptools
2601   package.
2602   
2603   This support is also available as a module ( = code which can be
2604   inserted in and removed from the running kernel whenever you want).
2605   If you want to compile it as a module, say M here and read
2606   Documentation/modules.txt.
2607 
2608 ISA Plug and Play support
2609 CONFIG_ISAPNP
2610   Say Y here if you would like support for ISA Plug and Play devices.
2611   Some information is in Documentation/isapnp.txt.
2612  
2613   This support is also available as a module called isapnp.o ( =
2614   code which can be inserted in and removed from the running kernel
2615   whenever you want). If you want to compile it as a module, say M
2616   here and read Documentation/modules.txt.
2617 
2618   If unsure, say Y.
2619 
2620 Support for hot-pluggable devices
2621 CONFIG_HOTPLUG
2622   Say Y here if you want to plug devices into your computer while
2623   the system is running, and be able to use them quickly.  In many
2624   cases, the devices can likewise be unplugged at any time too.
2625 
2626   One well known example of this is PCMCIA- or PC-cards, credit-card
2627   size devices such as network cards, modems or hard drives which are
2628   plugged into slots found on all modern laptop computers.
2629 
2630   Another example, used on modern desktops as well as laptops, is USB.
2631   Enable HOTPLUG with USB and KMOD, and your kernel will automatically
2632   call out to a user mode "policy agent" to load modules and set up
2633   software needed to use USB devices you plug in.  Get agent software
2634   (at http://www.linux-usb.org/policy.html) and install it.
2635 
2636 PCMCIA/Cardbus support
2637 CONFIG_PCMCIA
2638   Say Y here if you want to attach PCMCIA- or PC-cards to your Linux
2639   computer. These are credit-card size devices such as network cards,
2640   modems or hard drives often used with laptops computers. There are
2641   actually two varieties of these cards: the older 16 bit PCMCIA cards
2642   and the newer 32 bit CardBus cards. If you want to use CardBus
2643   cards, you need to say Y here and also to "CardBus support" below.
2644 
2645   To use your PC-cards, you will need supporting software from David 
2646   Hinds' pcmcia-cs package (see the file Documentation/Changes for 
2647   location). Please also read the PCMCIA-HOWTO, available from
2648   http://www.linuxdoc.org/docs.html#howto
2649 
2650   This driver is also available as a module ( = code which can be
2651   inserted in and removed from the running kernel whenever you want).
2652   When compiled this way, there will be modules called pcmcia_core.o
2653   and ds.o.  If you want to compile it as a module, say M here and
2654   read Documentation/modules.txt.
2655 
2656 CardBus support
2657 CONFIG_CARDBUS
2658   CardBus is a bus mastering architecture for PC-cards, which allows 
2659   for 32 bit PC-cards (the original PCMCIA standard specifies only 
2660   a 16 bit wide bus). Many newer PC-cards are actually CardBus cards.
2661 
2662   To use your PC-cards, you will need supporting software from David 
2663   Hinds' pcmcia-cs package (see the file Documentation/Changes for 
2664   location).
2665 
2666   If unsure, say Y.
2667 
2668 i82365/Yenta compatible bridge support
2669 CONFIG_I82365
2670   Say Y here to include support for PCMCIA and CardBus host bridges
2671   that are register compatible with the Intel i82365 and/or the Yenta
2672   specification: this includes virtually all modern PCMCIA bridges.
2673   "Bridge" is the name used for the hardware inside your computer that
2674   PCMCIA cards are plugged into. If unsure, say Y.
2675 
2676 Databook TCIC host bridge support
2677 CONFIG_TCIC
2678   Say Y here to include support for the Databook TCIC family of PCMCIA
2679   host bridges. These are only found on a handful of old systems.
2680   "Bridge" is the name used for the hardware inside your computer that
2681   PCMCIA cards are plugged into. If unsure, say N.
2682 
2683 System V IPC
2684 CONFIG_SYSVIPC
2685   Inter Process Communication is a suite of library functions and
2686   system calls which let processes (running programs) synchronize and
2687   exchange information. It is generally considered to be a good thing,
2688   and some programs won't run unless you say Y here. In particular, if
2689   you want to run the DOS emulator dosemu under Linux (read the
2690   DOSEMU-HOWTO, available from
2691   http://www.linuxdoc.org/docs.html#howto ), you'll need to say Y
2692   here.
2693   
2694   You can find documentation about IPC with "info ipc" and also in
2695   section 6.4 of the Linux Programmer's Guide, available from
2696   http://www.linuxdoc.org/docs.html#guide .
2697 
2698   Shared memory is now implemented using a new (minimal) virtual file
2699   system. To mount it automatically at system startup just add the
2700   following line to your /etc/fstab:
2701 
2702   none  /dev/shm        shm     defaults        0 0
2703 
2704   Saying Y here enlarges your kernel by about 18 KB. Just say Y.
2705 
2706 BSD Process Accounting
2707 CONFIG_BSD_PROCESS_ACCT
2708   If you say Y here, a user level program will be able to instruct the
2709   kernel (via a special system call) to write process accounting
2710   information to a file: whenever a process exits, information about
2711   that process will be appended to the file by the kernel. The
2712   information includes things such as creation time, owning user,
2713   command name, memory usage, controlling terminal etc. (the complete
2714   list is in the struct acct in include/linux/acct.h). It is up to the
2715   user level program to do useful things with this information. This
2716   is generally a good idea, so say Y.
2717   
2718 Sysctl support
2719 CONFIG_SYSCTL
2720   The sysctl interface provides a means of dynamically changing
2721   certain kernel parameters and variables on the fly without requiring
2722   a recompile of the kernel or reboot of the system. The primary
2723   interface consists of a system call, but if you say Y to "/proc
2724   file system support", a tree of modifiable sysctl entries will be
2725   generated beneath the /proc/sys directory. They are explained in the
2726   files in Documentation/sysctl/. Note that enabling this option will
2727   enlarge the kernel by at least 8 KB.
2728 
2729   As it is generally a good thing, you should say Y here unless
2730   building a kernel for install/rescue disks or your system is very
2731   limited in memory.
2732 
2733 Kernel core (/proc/kcore) format
2734 CONFIG_KCORE_ELF
2735   If you enabled support for /proc file system then the file 
2736   /proc/kcore will contain the kernel core image. This can be used 
2737   in gdb:
2738 
2739   $ cd /usr/src/linux ; gdb vmlinux /proc/kcore
2740 
2741   You have two choices here: ELF and A.OUT. Selecting ELF will make 
2742   /proc/kcore appear in ELF core format as defined by the Executable
2743   and Linking Format specification. Selecting A.OUT will choose the
2744   old "a.out" format which may be necessary for some old versions
2745   of binutils or on some architectures.
2746 
2747   This is especially useful if you have compiled the kernel with the 
2748   "-g" option to preserve debugging information. It is mainly used 
2749   for examining kernel data structures on the live kernel so if you 
2750   don't understand what this means or are not a kernel hacker, just 
2751   leave it at its default value ELF.
2752 
2753 Kernel support for ELF binaries
2754 CONFIG_BINFMT_ELF
2755   ELF (Executable and Linkable Format) is a format for libraries and
2756   executables used across different architectures and operating
2757   systems. Saying Y here will enable your kernel to run ELF binaries
2758   and enlarge it by about 13 KB. ELF support under Linux has now all
2759   but replaced the traditional Linux a.out formats (QMAGIC and ZMAGIC)
2760   because it is portable (this does *not* mean that you will be able
2761   to run executables from different architectures or operating systems
2762   however) and makes building run-time libraries very easy. Many new
2763   executables are distributed solely in ELF format. You definitely
2764   want to say Y here.
2765 
2766   Information about ELF is contained in the ELF HOWTO available from
2767   http://www.linuxdoc.org/docs.html#howto .
2768 
2769   If you find that after upgrading from Linux kernel 1.2 and saying Y
2770   here, you still can't run any ELF binaries (they just crash), then
2771   you'll have to install the newest ELF runtime libraries, including
2772   ld.so (check the file Documentation/Changes for location and latest
2773   version).
2774 
2775   If you want to compile this as a module ( = code which can be
2776   inserted in and removed from the running kernel whenever you want),
2777   say M here and read Documentation/modules.txt. The module will be
2778   called binfmt_elf.o. Saying M or N here is dangerous because some
2779   crucial programs on your system might be in ELF format.
2780 
2781 Kernel support for A.OUT binaries
2782 CONFIG_BINFMT_AOUT
2783   A.out (Assembler.OUTput) is a set of formats for libraries and
2784   executables used in the earliest versions of UNIX. Linux used the
2785   a.out formats QMAGIC and ZMAGIC until they were replaced with the
2786   ELF format.
2787 
2788   As more and more programs are converted to ELF, the use for a.out
2789   will gradually diminish. If you disable this option it will reduce
2790   your kernel by one page. This is not much and by itself does not
2791   warrant removing support. However its removal is a good idea if you
2792   wish to ensure that absolutely none of your programs will use this
2793   older executable format. If you don't know what to answer at this
2794   point then answer Y. If someone told you "You need a kernel with
2795   QMAGIC support" then you'll have to say Y here. You may answer M to
2796   compile a.out support as a module and later load the module when you
2797   want to use a program or library in a.out format. The module will be
2798   called binfmt_aout.o. Saying M or N here is dangerous though,
2799   because some crucial programs on your system might still be in A.OUT
2800   format.
2801 
2802 Kernel support for Linux/Intel ELF binaries
2803 CONFIG_BINFMT_EM86
2804   Say Y here if you want to be able to execute Linux/Intel ELF
2805   binaries just like native Alpha binaries on your Alpha machine. For
2806   this to work, you need to have the emulator /usr/bin/em86 in place.
2807 
2808   You can get the same functionality by saying N here and saying Y to
2809   "Kernel support for MISC binaries". 
2810 
2811   You may answer M to compile the emulation support as a module and
2812   later load the module when you want to use a Linux/Intel binary. The
2813   module will be called binfmt_em86.o. If unsure, say Y.
2814 
2815 Kernel support for MISC binaries
2816 CONFIG_BINFMT_MISC
2817   If you say Y here, it will be possible to plug wrapper-driven binary
2818   formats into the kernel. You will like this especially when you use
2819   programs that need an interpreter to run like Java, Python or
2820   Emacs-Lisp. It's also useful if you often run DOS executables under
2821   the Linux DOS emulator DOSEMU (read the DOSEMU-HOWTO, available from
2822   http://www.linuxdoc.org/docs.html#howto ). Once you have
2823   registered such a binary class with the kernel, you can start one of
2824   those programs simply by typing in its name at a shell prompt; Linux
2825   will automatically feed it to the correct interpreter.
2826 
2827   You can do other nice things, too. Read the file
2828   Documentation/binfmt_misc.txt to learn how to use this feature, and
2829   Documentation/java.txt for information about how to include Java
2830   support.
2831 
2832   You must say Y to "/proc file system support" (CONFIG_PROC_FS) to
2833   use this part of the kernel.
2834 
2835   You may say M here for module support and later load the module when
2836   you have use for it; the module is called binfmt_misc.o. If you
2837   don't know what to answer at this point, say Y.
2838 
2839 Solaris binary emulation (EXPERIMENTAL)
2840 CONFIG_SOLARIS_EMUL
2841   This is experimental code which will enable you to run (many)
2842   Solaris binaries on your SPARC Linux machine. 
2843 
2844   This code is also available as a module ( = code which can be
2845   inserted in and removed from the running kernel whenever you want).
2846   The module will be called solaris.o. If you want to compile it as a
2847   module, say M here and read Documentation/modules.txt.
2848 
2849 Processor family
2850 CONFIG_M386
2851   This is the processor type of your CPU. This information is used for
2852   optimizing purposes. In order to compile a kernel that can run on
2853   all x86 CPU types (albeit not optimally fast), you can specify
2854   "386" here.
2855 
2856   The kernel will not necessarily run on earlier architectures than
2857   the one you have chosen, e.g. a Pentium optimized kernel will run on
2858   a PPro, but not necessarily on a i486.
2859 
2860   Here are the settings recommended for greatest speed:
2861    - "386" for the AMD/Cyrix/Intel 386DX/DXL/SL/SLC/SX, Cyrix/TI
2862      486DLC/DLC2, UMC 486SX-S and NexGen Nx586. Only "386" kernels will
2863      run on a 386 class machine.
2864    - "486" for the AMD/Cyrix/IBM/Intel 486DX/DX2/DX4 or
2865      SL/SLC/SLC2/SLC3/SX/SX2 and UMC U5D or U5S.
2866    - "586" for generic Pentium CPUs, possibly lacking the TSC 
2867      (time stamp counter) register.
2868    - "Pentium-Classic" for the Intel Pentium.
2869    - "Pentium-MMX" for the Intel Pentium MMX.
2870    - "Pentium-Pro" for the Intel Pentium Pro/Celeron/Pentium II.
2871    - "Pentium-III" for the Intel Pentium III.
2872    - "Pentium-4" for the Intel Pentium 4
2873    - "K6" for the AMD K6, K6-II and K6-III (aka K6-3D).
2874    - "Athlon" for the AMD Athlon (K7).
2875    - "Crusoe" for the Transmeta Crusoe series.
2876    - "Winchip-C6" for original IDT Winchip.
2877    - "Winchip-2" for IDT Winchip 2.
2878    - "Winchip-2A" for IDT Winchips with 3dNow! capabilities.
2879 
2880   If you don't know what to do, choose "386".
2881 
2882 VGA text console
2883 CONFIG_VGA_CONSOLE
2884   Saying Y here will allow you to use Linux in text mode through a
2885   display that complies with the generic VGA standard. Virtually
2886   everyone wants that. 
2887 
2888   The program SVGATextMode can be used to utilize SVGA video cards to
2889   their full potential in text mode. Download it from
2890   ftp://metalab.unc.edu/pub/Linux/utils/console .
2891 
2892   Say Y.
2893 
2894 Video mode selection support
2895 CONFIG_VIDEO_SELECT
2896   This enables support for text mode selection on kernel startup. If
2897   you want to take advantage of some high-resolution text mode your
2898   card's BIOS offers, but the traditional Linux utilities like
2899   SVGATextMode don't, you can say Y here and set the mode using the
2900   "vga=" option from your boot loader (lilo or loadlin) or set
2901   "vga=ask" which brings up a video mode menu on kernel startup. (Try
2902   "man bootparam" or see the documentation of your boot loader about
2903   how to pass options to the kernel.)
2904 
2905   Read the file Documentation/svga.txt for more information about the
2906   Video mode selection support. If unsure, say N.
2907 
2908 Support for frame buffer devices (EXPERIMENTAL)
2909 CONFIG_FB
2910   The frame buffer device provides an abstraction for the graphics
2911   hardware. It represents the frame buffer of some video hardware and
2912   allows application software to access the graphics hardware through
2913   a well-defined interface, so the software doesn't need to know
2914   anything about the low-level (hardware register) stuff. 
2915 
2916   Frame buffer devices work identically across the different
2917   architectures supported by Linux and make the implementation of
2918   application programs easier and more portable; at this point, an X
2919   server exists which uses the frame buffer device exclusively.
2920   On several non-X86 architectures, the frame buffer device is the
2921   only way to use the graphics hardware.
2922  
2923   The device is accessed through special device nodes, usually located
2924   in the /dev directory, i.e. /dev/fb*.
2925 
2926   You need an utility program called fbset to make full use of frame
2927   buffer devices. Please read Documentation/fb/framebuffer.txt and the
2928   Framebuffer-HOWTO at
2929   http://www.tahallah.demon.co.uk/programming/prog.html for more
2930   information.
2931 
2932   Say Y here and to the driver for your graphics board below if you
2933   are compiling a kernel for a non-x86 architecture.
2934 
2935   If you are compiling for the x86 architecture, you can say Y if you
2936   want to play with it, but it is not essential. Please note that
2937   running graphical applications that directly touch the hardware
2938   (e.g. an accelerated X server) and that are not frame buffer
2939   device-aware may cause unexpected results. If unsure, say N.
2940 
2941 Acorn VIDC support
2942 CONFIG_FB_ACORN
2943   This is the frame buffer device driver for the Acorn VIDC graphics
2944   hardware found in Acorn RISC PCs and other ARM-based machines.  If
2945   unsure, say N.
2946 
2947 Amiga native chipset support
2948 CONFIG_FB_AMIGA
2949   This is the frame buffer device driver for the builtin graphics
2950   chipset found in Amigas.
2951 
2952   The driver is also available as a module ( = code which can be
2953   inserted and removed from the running kernel whenever you want). The
2954   module will be called amifb.o. If you want to compile it as a
2955   module, say M here and read Documentation/modules.txt.
2956 
2957 Amiga OCS chipset support
2958 CONFIG_FB_AMIGA_OCS
2959   This enables support for the original Agnus and Denise video chips,
2960   found in the Amiga 1000 and most A500's and A2000's. If you intend
2961   to run Linux on any of these systems, say Y; otherwise say N.
2962 
2963 Amiga ECS chipset support
2964 CONFIG_FB_AMIGA_ECS
2965   This enables support for the Enhanced Chip Set, found in later
2966   A500's, later A2000's, the A600, the A3000, the A3000T and CDTV. If
2967   you intend to run Linux on any of these systems, say Y; otherwise
2968   say N.
2969 
2970 Amiga AGA chipset support
2971 CONFIG_FB_AMIGA_AGA
2972   This enables support for the Advanced Graphics Architecture (also
2973   known as the AGA or AA) Chip Set, found in the A1200, A4000, A4000T
2974   and CD32. If you intend to run Linux on any of these systems, say Y;
2975   otherwise say N.
2976 
2977 Amiga CyberVision support
2978 CONFIG_FB_CYBER
2979   This enables support for the Cybervision 64 graphics card from
2980   Phase5. Please note that its use is not all that intuitive (i.e. if
2981   you have any questions, be sure to ask!). Say N unless you have a
2982   Cybervision 64 or plan to get one before you next recompile the
2983   kernel. Please note that this driver DOES NOT support the
2984   Cybervision 64 3D card, as they use incompatible video chips.
2985 
2986 CyberPro 20x0 support
2987 CONFIG_FB_CYBER2000
2988   This enables support for the Integraphics CyberPro 20x0 and 5000
2989   VGA chips used in the Rebel.com Netwinder and other machines.
2990   Say Y if you have a NetWinder or a graphics card containing this
2991   device, otherwise say N.
2992 
2993 Amiga CyberVision3D support (EXPERIMENTAL)
2994 CONFIG_FB_VIRGE
2995   This enables support for the Cybervision 64/3D graphics card from
2996   Phase5. Please note that its use is not all that intuitive (i.e. if
2997   you have any questions, be sure to ask!). Say N unless you have a
2998   Cybervision 64/3D or plan to get one before you next recompile the
2999   kernel. Please note that this driver DOES NOT support the older
3000   Cybervision 64 card, as they use incompatible video chips.
3001 
3002 Amiga RetinaZ3 support (EXPERIMENTAL)
3003 CONFIG_FB_RETINAZ3
3004   This enables support for the Retina Z3 graphics card. Say N unless
3005   you have a Retina Z3 or plan to get one before you next recompile
3006   the kernel.
3007 
3008 Cirrus Logic generic driver (EXPERIMENTAL)
3009 CONFIG_FB_CLGEN
3010   This enables support for Cirrus Logic GD542x/543x based boards on
3011   Amiga: SD64, Piccolo, Picasso II/II+, Picasso IV, or EGS Spectrum.
3012 
3013   If you have a PCI-based system, this enables support for these
3014   chips: GD-543x, GD-544x, GD-5480.
3015 
3016   Please read the file Documentation/fb/clgenfb.txt.
3017 
3018   Say N unless you have such a graphics board or plan to get one
3019   before you next recompile the kernel.
3020 
3021 Permedia2 support (EXPERIMENTAL)
3022 CONFIG_FB_PM2
3023   Say Y here if this is your graphics board.
3024 
3025 Apollo support
3026 CONFIG_APOLLO
3027   Say Y here if you want to run Linux on an MC680x0-based Apollo
3028   Domain workstation such as the DN3500.
3029 
3030 Apollo 3c505 support
3031 CONFIG_APOLLO_ELPLUS
3032   Say Y or M here if your Apollo has a 3Com 3c505 ISA Ethernet card.
3033   If you don't have one made for Apollos, you can use one from a PC,
3034   except that your Apollo won't be able to boot from it (because the
3035   code in the ROM will be for a PC).
3036 
3037 Atari native chipset support
3038 CONFIG_FB_ATARI
3039   This is the frame buffer device driver for the builtin graphics
3040   chipset found in Ataris.
3041 
3042 Open Firmware frame buffer device support 
3043 CONFIG_FB_OF
3044   Say Y if you want support with Open Firmware for your graphics
3045   board.
3046 
3047 S3 Trio frame buffer device support 
3048 CONFIG_FB_S3TRIO
3049   If you have a S3 Trio say Y. Say N for S3 Virge. 
3050 
3051 3Dfx Banshee/Voodoo3 display support (EXPERIMENTAL)
3052 CONFIG_FB_3DFX
3053   This driver supports graphics boards with the 3Dfx Banshee/Voodoo3
3054   chips. Say Y if you have such a graphics board.
3055 
3056   The driver is also available as a module ( = code which can be
3057   inserted and removed from the running kernel whenever you want). The
3058   module will be called tdfxfb.o. If you want to compile it as a
3059   module, say M here and read Documentation/modules.txt.
3060 
3061 nVidia Riva support (EXPERIMENTAL)
3062 CONFIG_FB_RIVA
3063   This driver supports graphics boards with the nVidia Riva (aka TNTx)
3064   chips.
3065   Say Y if you have such a graphics board.
3066 
3067   The driver is also available as a module ( = code which can be
3068   inserted and removed from the running kernel whenever you want). The
3069   module will be called rivafb.o. If you want to compile it as a
3070   module, say M here and read Documentation/modules.txt.
3071 
3072 ATI Mach64 display support (EXPERIMENTAL)
3073 CONFIG_FB_ATY
3074   This driver supports graphics boards with the ATI Mach64 chips.
3075   Say Y if you have such a graphics board.
3076 
3077   The driver is also available as a module ( = code which can be
3078   inserted and removed from the running kernel whenever you want). The
3079   module will be called atyfb.o. If you want to compile it as a
3080   module, say M here and read Documentation/modules.txt.
3081   
3082 ATI Rage128 display support (EXPERIMENTAL)
3083 CONFIG_FB_ATY128
3084   This driver supports graphics boards with the ATI Rage128 chips.
3085   Say Y if you have such a graphics board and read
3086   Documentation/fb/aty128fb.txt. 
3087 
3088   The driver is also available as a module ( = code which can be
3089   inserted and removed from the running kernel whenever you want). The
3090   module will be called aty128fb.o. If you want to compile it as a
3091   module, say M here and read Documentation/modules.txt.
3092 
3093 PowerMac "control" frame buffer device support
3094 CONFIG_FB_CONTROL
3095   This driver supports a frame buffer for the graphics adapter in the
3096   Power Macintosh 7300 and others.
3097 
3098 PowerMac "platinum" frame buffer device support
3099 CONFIG_FB_PLATINUM
3100   This driver supports a frame buffer for the "platinum" graphics
3101   adapter in some Power Macintoshes.
3102 
3103 PowerMac "valkyrie" frame buffer device support
3104 CONFIG_FB_VALKYRIE
3105   This driver supports a frame buffer for the "valkyrie" graphics
3106   adapter in some Power Macintoshes.
3107 
3108 Chips 65550 display support
3109 CONFIG_FB_CT65550
3110   This is the frame buffer device driver for the Chips & Technologies
3111   65550 graphics chip in PowerBooks.
3112 
3113 TGA frame buffer support
3114 CONFIG_FB_TGA
3115   This is the frame buffer device driver for generic TGA graphic
3116   cards. Say Y if you have one of those.
3117 
3118 VESA VGA graphics console
3119 CONFIG_FB_VESA
3120   This is the frame buffer device driver for generic VESA 2.0
3121   compliant graphic cards. The older VESA 1.2 cards are not supported.
3122   You will get a boot time penguin logo at no additional cost. Please
3123   read Documentation/fb/vesafb.txt. If unsure, say Y.
3124 
3125 VGA 16-color planar support
3126 CONFIG_FBCON_VGA_PLANES
3127   This low level frame buffer console driver enable the kernel to use
3128   the 16-color planar modes of the old VGA cards where the bits of
3129   each pixel are separated into 4 planes. 
3130 
3131   Only answer Y here if you have a (very old) VGA card that isn't VESA
3132   2 compatible.
3133 
3134 VGA 16-color graphics console
3135 CONFIG_FB_VGA16
3136   This is the frame buffer device driver for VGA 16 color graphic
3137   cards. Say Y if you have such a card.
3138 
3139   This code is also available as a module. If you want to compile it
3140   as a module ( = code which can be inserted in and removed from the
3141   running kernel whenever you want), say M here and read
3142   Documentation/modules.txt. The module will be called vga16fb.o.
3143 
3144 Select other compiled-in fonts
3145 CONFIG_FBCON_FONTS
3146   Say Y here if you would like to use fonts other than the default
3147   your frame buffer console usually use.
3148 
3149   Note that the answer to this question won't directly affect the
3150   kernel: saying N will just cause this configure script to skip all
3151   the questions about foreign fonts.
3152 
3153   If unsure, say N (the default choices are safe).
3154 
3155 VGA 8x16 font
3156 CONFIG_FONT_8x16
3157   This is the "high resolution" font for the VGA frame buffer (the one
3158   provided by the VGA text console 80x25 mode.
3159 
3160   If unsure, say Y.
3161 
3162 Support only 8 pixels wide fonts
3163 CONFIG_FBCON_FONTWIDTH8_ONLY
3164   Answer Y here will make the kernel provide only the 8x8 fonts (these
3165   are the less readable).
3166 
3167   If unsure, say N.
3168 
3169 Sparc console 8x16 font
3170 CONFIG_FONT_SUN8x16
3171   This is the high resolution console font for Sun machines. Say Y.
3172 
3173 Sparc console 12x22 font (not supported by all drivers)
3174 CONFIG_FONT_SUN12x22
3175   This is the high resolution console font for Sun machines with very
3176   big letters (like the letters used in the SPARC PROM). If the
3177   standard font is unreadable for you, say Y, otherwise say N.
3178 
3179 VGA 8x8 font
3180 CONFIG_FONT_8x8
3181   This is the "high resolution" font for the VGA frame buffer (the one
3182   provided by the text console 80x50 (and higher) modes). 
3183 
3184   Note that this is a poor quality font. The VGA 8x16 font is quite a
3185   lot more readable. 
3186 
3187   Given the resolution provided by the frame buffer device, answer N
3188   here is safe.
3189 
3190 Backward compatibility mode for Xpmac
3191 CONFIG_FB_COMPAT_XPMAC
3192   If you use the Xpmac X server (common with mklinux), you'll need to
3193   say Y here to use X. You should consider changing to XFree86 which
3194   includes a server that supports the frame buffer device directly
3195   (XF68_FBDev).
3196 
3197 HGA monochrome support (EXPERIMENTAL)
3198 CONFIG_FB_HGA
3199   Say Y here if you have a Hercules mono graphics card.
3200 
3201   This driver is also available as a module ( = code which can be
3202   inserted and removed from the running kernel whenever you want).
3203   The module will be called hgafb.o. If you want to compile it as
3204   a module, say M here and read Documentation/modules.txt.
3205 
3206   As this card technology is 15 years old, most people will answer N
3207   here.
3208 
3209 Matrox unified accelerated driver (EXPERIMENTAL)
3210 CONFIG_FB_MATROX
3211   Say Y here if you have a Matrox Millennium, Matrox Millennium II,
3212   Matrox Mystique, Matrox Mystique 220, Matrox Productiva G100, Matrox
3213   Mystique G200, Matrox Millennium G200, Matrox Marvel G200 video,
3214   Matrox G400 or G450 card in your box. At this time, support for the G100
3215   is untested and support for G450 is highly experimental.
3216 
3217   This driver is also available as a module ( = code which can be
3218   inserted and removed from the running kernel whenever you want).
3219   The module will be called matroxfb.o. If you want to compile it as
3220   a module, say M here and read Documentation/modules.txt.
3221 
3222   You can pass several parameters to the driver at boot time or at
3223   module load time. The parameters look like "video=matrox:XXX", where
3224   the meaning of XXX can be found at the end of the main source file
3225   (drivers/video/matroxfb.c). Please see the file
3226   Documentation/fb/matroxfb.txt. 
3227 
3228 Matrox Millennium support
3229 CONFIG_FB_MATROX_MILLENIUM
3230   Say Y here if you have a Matrox Millennium or Matrox Millennium II
3231   video card. If you select "Advanced lowlevel driver options" below,
3232   you should check 4 bpp packed pixel, 8 bpp packed pixel, 16 bpp
3233   packed pixel, 24 bpp packed pixel and 32 bpp packed pixel. You can
3234   also use font widths different from 8.
3235 
3236 Matrox Mystique support
3237 CONFIG_FB_MATROX_MYSTIQUE
3238   Say Y here if you have a Matrox Mystique or Matrox Mystique 220
3239   video card. If you select "Advanced lowlevel driver options" below,
3240   you should check 8 bpp packed pixel, 16 bpp packed pixel, 24 bpp
3241   packed pixel and 32 bpp packed pixel. You can also use font widths
3242   different from 8.
3243 
3244 Matrox G100/G200/G400/G450 support
3245 CONFIG_FB_MATROX_G100
3246   Say Y here if you have a Matrox G100, G200, G400 or G450 based
3247   video card. If you select "Advanced lowlevel driver options", you 
3248   should check 8 bpp packed pixel, 16 bpp packed pixel, 24 bpp packed 
3249   pixel and 32 bpp packed pixel. You can also use font widths 
3250   different from 8.
3251 
3252   If you need support for G400 secondary head, you must first say Y to
3253   "I2C support" and "I2C bit-banging support" in the character devices
3254   section, and then to "Matrox I2C support" and "G400 second head
3255   support" here in the framebuffer section.
3256 
3257 Matrox I2C support
3258 CONFIG_FB_MATROX_I2C
3259   This drivers creates I2C buses which are needed for accessing the
3260   DDC (I2C) bus present on all Matroxes, an I2C bus which
3261   interconnects Matrox optional devices, like MGA-TVO on G200 and
3262   G400, and the secondary head DDC bus, present on G400 only.
3263   
3264   You can say Y or M here if you want to experiment with monitor 
3265   detection code. You must say Y or M here if you want to use either
3266   second head of G400 or MGA-TVO on G200 or G400.
3267   
3268   If you compile it as module, it will create a module named
3269   i2c-matroxfb.o.
3270   
3271 Matrox G400 second head support
3272 CONFIG_FB_MATROX_MAVEN
3273   WARNING !!! This support does not work with G450 !!!
3274 
3275   Say Y or M here if you want to use a secondary head (meaning two
3276   monitors in parallel) on G400 or MGA-TVO add-on on G200. Secondary
3277   head is not compatible with accelerated XFree 3.3.x SVGA servers -
3278   secondary head output is blanked while you are in X. With XFree
3279   3.9.17 preview you can use both heads if you use SVGA over fbdev or
3280   the fbdev driver on first head and the fbdev driver on second head.
3281   
3282   If you compile it as module, two modules are created,
3283   matroxfb_crtc2.o and matroxfb_maven.o. Matroxfb_maven is needed for
3284   both G200 and G400, matroxfb_crtc2 is needed only by G400. You must
3285   also load i2c-matroxfb to get it to run.
3286   
3287   The driver starts in monitor mode and you must use the matroxset
3288   tool (available at ftp://platan.vc.cvut.cz/pub/linux/matrox-latest)
3289   to switch it to PAL or NTSC or to swap primary and secondary head
3290   outputs. Secondary head driver also always start in 640x480
3291   resolution, you must use fbset to change it.
3292   
3293   Also do not forget that second head supports only 16 and 32 bpp
3294   packed pixels, so it is a good idea to compile them into the kernel
3295   too. You can use only some font widths, as the driver uses generic
3296   painting procedures (the secondary head does not use acceleration
3297   engine).
3298   
3299   There is no need for enabling 'Matrox multihead support' if you have
3300   only one Matrox card in the box.
3301 
3302 Matrox G450 second head support
3303 CONFIG_FB_MATROX_G450
3304   Say Y or M here if you want to use a secondary head (meaning two
3305   monitors in parallel) on G450.
3306 
3307   If you compile it as module, two modules are created,
3308   matroxfb_crtc2.o and matroxfb_g450.o. Both modules are needed if you
3309   want two independent display devices.
3310 
3311   The driver starts in monitor mode and currently does not support
3312   output in TV modes. You must use the matroxset tool (available
3313   at ftp://platan.vc.cvut.cz/pub/linux/matrox-latest) to swap primary
3314   and secondary head outputs. Secondary head driver always start in
3315   640x480 resolution and you must use fbset to change it.
3316 
3317   Also do not forget that second head supports only 16 and 32 bpp
3318   packed pixels, so it is a good idea to compile them into the kernel
3319   too. You can use only some font widths, as the driver uses generic
3320   painting procedures (the secondary head does not use acceleration
3321   engine).
3322 
3323   There is no need for enabling 'Matrox multihead support' if you have
3324   only one Matrox card in the box.
3325 
3326 Matrox unified driver multihead support
3327 CONFIG_FB_MATROX_MULTIHEAD
3328   Say Y here if you have more than one (supported) Matrox device in
3329   your computer and you want to use all of them for different monitors
3330   ("multihead"). If you have only one device, you should say N because
3331   the driver compiled with Y is larger and a bit slower, especially on
3332   ia32 (ix86).
3333 
3334   If you said M to "Matrox unified accelerated driver" and N here, you
3335   will still be able to use several Matrox devices simultaneously:
3336   insert several instances of the module matroxfb.o into the kernel
3337   with insmod, supplying the parameter "dev=N" where N is 0, 1, etc.
3338   for the different Matrox devices. This method is slightly faster but
3339   uses 40 KB of kernel memory per Matrox card.
3340 
3341 MDA text console (dual-headed)
3342 CONFIG_MDA_CONSOLE
3343   Say Y here if you have an old MDA or monochrome Hercules graphics
3344   adapter in your system acting as a second head ( = video card). You
3345   will then be able to use two monitors with your Linux system. Do not
3346   say Y here if your MDA card is the primary card in your system; the
3347   normal VGA driver will handle it.
3348   
3349   This driver is also available as a module ( = code which can be
3350   inserted and removed from the running kernel whenever you want).
3351   The module will be called mdacon.o. If you want to compile it as
3352   a module, say M here and read Documentation/modules.txt.
3353   
3354   If unsure, say N.
3355 
3356 SBUS and UPA frame buffers
3357 CONFIG_FB_SBUS
3358   Say Y if you want support for SBUS or UPA based frame buffer device.
3359 
3360 Creator/Creator3D support
3361 CONFIG_FB_CREATOR
3362   This is the frame buffer device driver for the Creator and Creator3D
3363   graphics boards.
3364 
3365 CGsix (GX,TurboGX) support
3366 CONFIG_FB_CGSIX
3367   This is the frame buffer device driver for the CGsix (GX, TurboGX)
3368   frame buffer.
3369 
3370 BWtwo support
3371 CONFIG_FB_BWTWO
3372   This is the frame buffer device driver for the BWtwo frame buffer.
3373 
3374 CGthree support
3375 CONFIG_FB_CGTHREE
3376   This is the frame buffer device driver for the CGthree frame buffer.
3377 
3378 TCX (SS4/SS5 only) support
3379 CONFIG_FB_TCX
3380   This is the frame buffer device driver for the TCX 24/8bit frame
3381   buffer.
3382 
3383 Virtual Frame Buffer support (ONLY FOR TESTING!)
3384 CONFIG_FB_VIRTUAL
3385   This is a `virtual' frame buffer device. It operates on a chunk of
3386   unswapable kernel memory instead of on the memory of a graphics
3387   board. This means you cannot see any output sent to this frame
3388   buffer device, while it does consume precious memory. The main use
3389   of this frame buffer device is testing and debugging the frame
3390   buffer subsystem. Do NOT enable it for normal systems! To protect
3391   the innocent, it has to be enabled explicitly at boot time using the
3392   kernel option `video=vfb:'.
3393 
3394   This driver is also available as a module ( = code which can be
3395   inserted and removed from the running kernel whenever you want). The
3396   module will be called vfb.o. If you want to compile it as a module,
3397   say M here and read Documentation/modules.txt.
3398  
3399   If unsure, say N.
3400 
3401 CONFIG_FB_SA1100
3402   This is a framebuffer device for the SA-1100 LCD Controller.
3403   See http://www.linux-fbdev.org/ for information on framebuffer
3404   devices.
3405 
3406   If you plan to use the LCD display with your SA-1100 system, say
3407   Y here.
3408 
3409 Advanced low level driver options
3410 CONFIG_FBCON_ADVANCED
3411   The frame buffer console uses character drawing routines that are
3412   tailored to the specific organization of pixels in the memory of
3413   your graphics hardware. These are called the low level frame buffer
3414   console drivers. Note that they are used for text console output
3415   only; they are NOT needed for graphical applications.
3416 
3417   If you say N here, the needed low level drivers are automatically
3418   enabled, depending on what frame buffer devices you selected above.
3419   This is recommended for most users.
3420 
3421   If you say Y here, you have more fine-grained control over which low
3422   level drivers are enabled. You can e.g. leave out low level drivers
3423   for color depths you do not intend to use for text consoles.
3424 
3425   Low level frame buffer console drivers can be modules ( = code which
3426   can be inserted and removed from the running kernel whenever you
3427   want). The modules will be called fbcon-*.o. If you want to compile
3428   (some of) them as modules, read Documentation/modules.txt.
3429   
3430   If unsure, say N.
3431 
3432 Monochrome support
3433 CONFIG_FBCON_MFB
3434   This is the low level frame buffer console driver for monochrome
3435   (2 colors) packed pixels.
3436 
3437 2 bpp packed pixels support
3438 CONFIG_FBCON_CFB2
3439   This is the low level frame buffer console driver for 2 bits per
3440   pixel (4 colors) packed pixels.
3441 
3442 4 bpp packed pixels support
3443 CONFIG_FBCON_CFB4
3444   This is the low level frame buffer console driver for 4 bits per
3445   pixel (16 colors) packed pixels.
3446 
3447 8 bpp packed pixels support
3448 CONFIG_FBCON_CFB8
3449   This is the low level frame buffer console driver for 8 bits per
3450   pixel (256 colors) packed pixels.
3451 
3452 16 bpp packed pixels support
3453 CONFIG_FBCON_CFB16
3454   This is the low level frame buffer console driver for 15 or 16 bits
3455   per pixel (32K or 64K colors, also known as `hicolor') packed
3456   pixels.
3457 
3458 24 bpp packed pixels support
3459 CONFIG_FBCON_CFB24
3460   This is the low level frame buffer console driver for 24 bits per
3461   pixel (16M colors, also known as `truecolor') packed pixels. It is
3462   NOT for `sparse' 32 bits per pixel mode.
3463 
3464 32 bpp packed pixels support
3465 CONFIG_FBCON_CFB32
3466   This is the low level frame buffer console driver for 32 bits per
3467   pixel (16M colors, also known as `truecolor') sparse packed pixels.
3468 
3469 Amiga bitplanes support
3470 CONFIG_FBCON_AFB
3471   This is the low level frame buffer console driver for 1 to 8
3472   bitplanes (2 to 256 colors) on Amiga.
3473 
3474 Amiga interleaved bitplanes support
3475 CONFIG_FBCON_ILBM
3476   This is the low level frame buffer console driver for 1 to 8
3477   interleaved bitplanes (2 to 256 colors) on Amiga.
3478 
3479 Atari interleaved bitplanes (2 planes) support
3480 CONFIG_FBCON_IPLAN2P2
3481   This is the low level frame buffer console driver for 2 interleaved
3482   bitplanes (4 colors) on Atari.
3483 
3484 Atari interleaved bitplanes (4 planes) support
3485 CONFIG_FBCON_IPLAN2P4
3486   This is the low level frame buffer console driver for 4 interleaved
3487   bitplanes (16 colors) on Atari.
3488 
3489 Atari interleaved bitplanes (8 planes) support
3490 CONFIG_FBCON_IPLAN2P8
3491   This is the low level frame buffer console driver for 8 interleaved
3492   bitplanes (256 colors) on Atari.
3493 
3494 Mac variable bpp packed pixels support
3495 CONFIG_FBCON_MAC
3496   This is the low level frame buffer console driver for 1/2/4/8/16/32
3497   bits per pixel packed pixels on Mac. It supports variable font
3498   widths for low resolution screens.
3499   
3500 HGA monochrome support (EXPERIMENTAL)
3501 CONFIG_FBCON_HGA
3502   This is the low level frame buffer console driver for Hercules mono 
3503   graphics cards.
3504 
3505 VGA characters/attributes support
3506 CONFIG_FBCON_VGA
3507   This is the low level frame buffer console driver for VGA text mode;
3508   it is used by frame buffer device drivers that support VGA text
3509   mode.
3510 
3511 Parallel-port support
3512 CONFIG_PARPORT
3513   If you want to use devices connected to your machine's parallel port
3514   (the connector at the computer with 25 holes), e.g. printer, ZIP
3515   drive, PLIP link (Parallel Line Internet Protocol is mainly used to
3516   create a mini network by connecting the parallel ports of two local
3517   machines) etc., then you need to say Y here; please read
3518   Documentation/parport.txt and drivers/parport/BUGS-parport.
3519 
3520   For extensive information about drivers for many devices attaching
3521   to the parallel port see http://www.torque.net/linux-pp.html on the
3522   WWW.
3523 
3524   It is possible to share a single parallel port among several devices
3525   and it is safe to compile all the corresponding drivers into the
3526   kernel. If you want to compile parallel port support as a module ( =
3527   code which can be inserted in and removed from the running kernel
3528   whenever you want), say M here and read Documentation/modules.txt.
3529   The module will be called parport.o. If you have more than one
3530   parallel port and want to specify which port and IRQ to be used by
3531   this driver at module load time, take a look at
3532   Documentation/parport.txt.
3533 
3534   If unsure, say Y.
3535 
3536 PC-style hardware
3537 CONFIG_PARPORT_PC
3538   You should say Y here if you have a PC-style parallel port. All IBM
3539   PC compatible computers and some Alphas have PC-style parallel
3540   ports. 
3541 
3542   This code is also available as a module. If you want to compile it
3543   as a module ( = code which can be inserted in and removed from the
3544   running kernel whenever you want), say M here and read
3545   Documentation/modules.txt. The module will be called parport_pc.o.
3546   
3547   If unsure, say Y.
3548 
3549 Use FIFO/DMA if available
3550 CONFIG_PARPORT_PC_FIFO
3551   Many parallel port chipsets provide hardware that can speed up
3552   printing. Say Y here if you want to take advantage of that.
3553 
3554   As well as actually having a FIFO, or DMA capability, the kernel
3555   will need to know which IRQ the parallel port has. By default,
3556   parallel port interrupts will not be used, and so neither will the
3557   FIFO. See Documentation/parport.txt to find out how to specify
3558   which IRQ/DMA to use.
3559 
3560 SuperIO chipset support (EXPERIMENTAL)
3561 CONFIG_PARPORT_PC_SUPERIO
3562   Saying Y here enables some probes for Super-IO chipsets in order to
3563   find out things like base addresses, IRQ lines and DMA channels.  It
3564   is safe to say N.
3565 
3566 Support for PCMCIA management for PC-style ports
3567 CONFIG_PARPORT_PC_PCMCIA
3568   Say Y here if you need PCMCIA support for your PC-style parallel
3569   ports. If unsure, say N.
3570 
3571 Support foreign hardware
3572 CONFIG_PARPORT_OTHER
3573   Say Y here if you want to be able to load driver modules to support
3574   other non-standard types of parallel ports. This causes a
3575   performance loss, so most people say N.
3576 
3577 Sun Ultra/AX-style hardware 
3578 CONFIG_PARPORT_AX
3579   Say Y here if you need support for the parallel port hardware on Sun
3580   Ultra/AX machines. This code is also available as a module (say M),
3581   called parport_ax.o. If in doubt, saying N is the safe plan.
3582 
3583 Amiga built-in parallel port support
3584 CONFIG_PARPORT_AMIGA
3585   Say Y here if you need support for the parallel port hardware on
3586   Amiga machines. This code is also available as a module (say M),
3587   called parport_amiga.o. If in doubt, saying N is the safe plan.
3588 
3589 Atari built-in parallel port support
3590 CONFIG_PARPORT_ATARI
3591   Say Y here if you need support for the parallel port hardware on
3592   Atari machines. This code is also available as a module (say M),
3593   called parport_atari.o. If in doubt, saying N is the safe plan.
3594 
3595 Multiface 3 parallel port card support
3596 CONFIG_PARPORT_MFC3
3597   Say Y here if you need parallel port support for the MFC3 card.
3598   This code is also available as a module (say M), called
3599   parport_mfc3.o. If in doubt, saying N is the safe plan.
3600 
3601 Support IEEE1284 status readback
3602 CONFIG_PRINTER_READBACK
3603   If you have a device on your parallel port that support this
3604   protocol, this option will allow the device to report its status. It
3605   is safe to say Y.
3606 
3607 IEEE1284 transfer modes
3608 CONFIG_PARPORT_1284
3609   If you have a printer that supports status readback or device ID, or
3610   want to use a device that uses enhanced parallel port transfer modes
3611   such as EPP and ECP, say Y here to enable advanced IEEE 1284
3612   transfer modes. Also say Y if you want device ID information to
3613   appear in /proc/sys/dev/parport/*/autoprobe*. It is safe to say N.
3614  
3615 Enable loadable module support
3616 CONFIG_MODULES
3617   Kernel modules are small pieces of compiled code which can be
3618   inserted in or removed from the running kernel, using the programs
3619   insmod and rmmod. This is described in the file
3620   Documentation/modules.txt, including the fact that you have to say
3621   "make modules" in order to compile the modules that you chose during
3622   kernel configuration. Modules can be device drivers, file systems,
3623   binary executable formats, and so on. If you think that you may want
3624   to make use of modules with this kernel in the future, then say Y
3625   here. If unsure, say Y.
3626 
3627 Set version information on all symbols for modules
3628 CONFIG_MODVERSIONS
3629   Usually, modules have to be recompiled whenever you switch to a new
3630   kernel. Saying Y here makes it possible, and safe, to use the
3631   same modules even after compiling a new kernel; this requires the
3632   program modprobe. All the software needed for module support is in
3633   the modutils package (check the file Documentation/Changes for
3634   location and latest version). NOTE: if you say Y here but don't
3635   have the program genksyms (which is also contained in the above
3636   mentioned modutils package), then the building of your kernel will
3637   fail. If you are going to use modules that are generated from
3638   non-kernel sources, you would benefit from this option. Otherwise
3639   it's not that important. So, N ought to be a safe bet.
3640 
3641 Kernel module loader support
3642 CONFIG_KMOD
3643   Normally when you have selected some drivers and/or file systems to
3644   be created as loadable modules, you also have the responsibility to
3645   load the corresponding modules (using the programs insmod or
3646   modprobe) before you can use them. If you say Y here however, the
3647   kernel will be able to load modules for itself: when a part of the
3648   kernel needs a module, it runs modprobe with the appropriate
3649   arguments, thereby loading the module if it is available. (This is a
3650   replacement for kerneld.) Say Y here and read about configuring it
3651   in Documentation/kmod.txt.
3652 
3653 ARP daemon support (EXPERIMENTAL)
3654 CONFIG_ARPD
3655   Normally, the kernel maintains an internal cache which maps IP 
3656   addresses to hardware addresses on the local network, so that
3657   Ethernet/Token Ring/ etc. frames are sent to the proper address on
3658   the physical networking layer. For small networks having a few
3659   hundred directly connected hosts or less, keeping this address
3660   resolution (ARP) cache inside the kernel works well. However,
3661   maintaining an internal ARP cache does not work well for very large
3662   switched networks, and will use a lot of kernel memory if TCP/IP
3663   connections are made to many machines on the network. 
3664 
3665   If you say Y here, the kernel's internal ARP cache will never grow
3666   to more than 256 entries (the oldest entries are expired in a LIFO
3667   manner) and communication will be attempted with the user space ARP
3668   daemon arpd. Arpd then answers the address resolution request either
3669   from its own cache or by asking the net.
3670 
3671   This code is experimental and also obsolete. If you want to use it,
3672   you need to find a version of the daemon arpd on the net somewhere,
3673   and you should also say Y to "Kernel/User network link driver",
3674   below. If unsure, say N.
3675 
3676 TCP/IP networking
3677 CONFIG_INET
3678   These are the protocols used on the Internet and on most local
3679   Ethernets. It is highly recommended to say Y here (this will enlarge
3680   your kernel by about 144 KB), since some programs (e.g. the X window
3681   system) use TCP/IP even if your machine is not connected to any
3682   other computer. You will get the so-called loopback device which
3683   allows you to ping yourself (great fun, that!).
3684 
3685   For an excellent introduction to Linux networking, please read the
3686   NET-3-HOWTO, available from
3687   http://www.linuxdoc.org/docs.html#howto .
3688 
3689   This option is also necessary if you want to use the full power of
3690   term (term is a program which gives you almost full Internet
3691   connectivity if you have a regular dial up shell account on some
3692   Internet connected Unix computer; for more information, read
3693   http://www.bart.nl/~patrickr/term-howto/Term-HOWTO.html ).
3694   
3695   If you say Y here and also to "/proc file system support" and
3696   "Sysctl support" below, you can change various aspects of the
3697   behavior of the TCP/IP code by writing to the (virtual) files in
3698   /proc/sys/net/ipv4/*; the options are explained in the file
3699   Documentation/networking/ip-sysctl.txt.
3700 
3701   Short answer: say Y.
3702 
3703 IP: multicasting
3704 CONFIG_IP_MULTICAST
3705   This is code for addressing several networked computers at once,
3706   enlarging your kernel by about 2 KB. You need multicasting if you
3707   intend to participate in the MBONE, a high bandwidth network on top
3708   of the Internet which carries audio and video broadcasts. More
3709   information about the MBONE is on the WWW at
3710   http://www-itg.lbl.gov/mbone/ . Information about the multicast
3711   capabilities of the various network cards is contained in
3712   Documentation/networking/multicast.txt. For most people, it's safe
3713   to say N.
3714 
3715 IP: advanced router
3716 CONFIG_IP_ADVANCED_ROUTER
3717   If you intend to run your Linux box mostly as a router, i.e. as a
3718   computer that forwards and redistributes network packets, say Y; you
3719   will then be presented with several options that allow more precise
3720   control about the routing process.
3721 
3722   The answer to this question won't directly affect the kernel:
3723   answering N will just cause this configure script to skip all the
3724   questions about advanced routing.
3725 
3726   Note that your box can only act as a router if you enable IP
3727   forwarding in your kernel; you can do that by saying Y to "/proc
3728   file system support" and "Sysctl support" below and executing the
3729   line
3730 
3731     echo "1" > /proc/sys/net/ipv4/ip_forward
3732 
3733   at boot time after the /proc file system has been mounted. 
3734 
3735   If you turn on IP forwarding, you will also get the rp_filter, which
3736   automatically rejects incoming packets if the routing table entry
3737   for their source address doesn't match the network interface they're
3738   arriving on. This has security advantages because it prevents the
3739   so-called IP spoofing, however it can pose problems if you use
3740   asymmetric routing (packets from you to a host take a different path
3741   than packets from that host to you) or if you operate a non-routing
3742   host which has several IP addresses on different interfaces. To turn
3743   rp_filter off use:
3744 
3745         echo 0 > /proc/sys/net/ipv4/conf/<device>/rp_filter
3746   or
3747         echo 0 > /proc/sys/net/ipv4/conf/all/rp_filter
3748 
3749   If unsure, say N here.
3750 
3751 IP: policy routing
3752 CONFIG_IP_MULTIPLE_TABLES
3753   Normally, a router decides what to do with a received packet based
3754   solely on the packet's final destination address. If you say Y here,
3755   the Linux router will also be able to take the packet's source
3756   address into account. Furthermore, if you also say Y to "IP: use TOS
3757   value as routing key" below, the TOS (Type-Of-Service) field of the
3758   packet can be used for routing decisions as well. In addition, if
3759   you say Y here and to "IP: fast network address translation" below,
3760   the router will also be able to modify source and destination
3761   addresses of forwarded packets.
3762 
3763   If you are interested in this, please see the preliminary
3764   documentation at http://www.compendium.com.ar/policy-routing.txt and
3765   ftp://post.tepkom.ru/pub/vol2/Linux/docs/advanced-routing.tex . You
3766   will need supporting software from ftp://ftp.inr.ac.ru/ip-routing/
3767   
3768   If unsure, say N.
3769   
3770 IP: equal cost multipath
3771 CONFIG_IP_ROUTE_MULTIPATH
3772   Normally, the routing tables specify a single action to be taken in
3773   a deterministic manner for a given packet. If you say Y here
3774   however, it becomes possible to attach several actions to a packet
3775   pattern, in effect specifying several alternative paths to travel
3776   for those packets. The router considers all these paths to be of
3777   equal "cost" and chooses one of them in a non-deterministic fashion
3778   if a matching packet arrives.
3779 
3780 IP: use TOS value as routing key
3781 CONFIG_IP_ROUTE_TOS
3782   The header of every IP packet carries a TOS (Type Of Service) value
3783   with which the packet requests a certain treatment, e.g. low latency
3784   (for interactive traffic), high throughput, or high reliability. If
3785   you say Y here, you will be able to specify different routes for
3786   packets with different TOS values.
3787 
3788 IP: use netfilter MARK value as routing key
3789 CONFIG_IP_ROUTE_FWMARK
3790   If you say Y here, you will be able to specify different routes for
3791   packets with different mark values (see iptables(8), MARK target).
3792 
3793 IP: verbose route monitoring
3794 CONFIG_IP_ROUTE_VERBOSE
3795   If you say Y here, which is recommended, then the kernel will print
3796   verbose messages regarding the routing, for example warnings about
3797   received packets which look strange and could be evidence of an
3798   attack or a misconfigured system somewhere. The information is
3799   handled by the klogd daemon which is responsible for kernel messages
3800   ("man klogd").
3801 
3802 IP: large routing tables
3803 CONFIG_IP_ROUTE_LARGE_TABLES
3804   If you have routing zones that grow to more than about 64 entries,
3805   you may want to say Y here to speed up the routing process.
3806 
3807 IP: fast network address translation
3808 CONFIG_IP_ROUTE_NAT
3809   If you say Y here, your router will be able to modify source and
3810   destination addresses of packets that pass through it, in a manner
3811   you specify. General information about Network Address Translation
3812   can be gotten from the document
3813   http://www.csn.tu-chemnitz.de/~mha/linux-ip-nat/diplom/nat.html
3814 
3815 IP: kernel level autoconfiguration
3816 CONFIG_IP_PNP
3817   This enables automatic configuration of IP addresses of devices and
3818   of the routing table during kernel boot, based on either information
3819   supplied on the kernel command line or by BOOTP or RARP protocols.
3820   You need to say Y only for diskless machines requiring network
3821   access to boot (in which case you want to say Y to "Root file system
3822   on NFS" as well), because all other machines configure the network
3823   in their startup scripts.
3824 
3825 BOOTP support
3826 CONFIG_IP_PNP_BOOTP
3827   If you want your Linux box to mount its whole root file system (the
3828   one containing the directory /) from some other computer over the
3829   net via NFS and you want the IP address of your computer to be
3830   discovered automatically at boot time using the BOOTP protocol (a
3831   special protocol designed for doing this job), say Y here. In case
3832   the boot ROM of your network card was designed for booting Linux and
3833   does BOOTP itself, providing all necessary information on the kernel
3834   command line, you can say N here. If unsure, say Y. Note that if you
3835   want to use BOOTP, a BOOTP server must be operating on your network.
3836   Read Documentation/nfsroot.txt for details.
3837 
3838 RARP support
3839 CONFIG_IP_PNP_RARP
3840   If you want your Linux box to mount its whole root file system (the
3841   one containing the directory /) from some other computer over the
3842   net via NFS and you want the IP address of your computer to be
3843   discovered automatically at boot time using the RARP protocol (an
3844   older protocol which is being obsoleted by BOOTP and DHCP), say Y
3845   here. Note that if you want to use RARP, a RARP server must be
3846   operating on your network. Read Documentation/nfsroot.txt for
3847   details.
3848 
3849 IP: tunneling
3850 CONFIG_NET_IPIP
3851   Tunneling means encapsulating data of one protocol type within
3852   another protocol and sending it over a channel that understands the
3853   encapsulating protocol. This particular tunneling driver implements
3854   encapsulation of IP within IP, which sounds kind of pointless, but
3855   can be useful if you want to make your (or some other) machine
3856   appear on a different network than it physically is, or to use
3857   mobile-IP facilities (allowing laptops to seamlessly move between
3858   networks without changing their IP addresses; check out
3859   http://anchor.cs.binghamton.edu/~mobileip/LJ/index.html ). 
3860 
3861   Saying Y to this option will produce two modules ( = code which can
3862   be inserted in and removed from the running kernel whenever you
3863   want). Most people won't need this and can say N.
3864 
3865 IP: GRE tunnels over IP
3866 CONFIG_NET_IPGRE
3867   Tunneling means encapsulating data of one protocol type within
3868   another protocol and sending it over a channel that understands the
3869   encapsulating protocol. This particular tunneling driver implements
3870   GRE (Generic Routing Encapsulation) and at this time allows
3871   encapsulating of IPv4 or IPv6 over existing IPv4 infrastructure.
3872   This driver is useful if the other endpoint is a Cisco router: Cisco
3873   likes GRE much better than the other Linux tunneling driver ("IP:
3874   tunneling" above). In addition, GRE allows multicast redistribution
3875   through the tunnel.
3876 
3877 IP: broadcast GRE over IP
3878 CONFIG_NET_IPGRE_BROADCAST
3879   One application of GRE/IP is to construct a broadcast WAN (Wide Area
3880   Network), which looks like a normal Ethernet LAN (Local Area
3881   Network), but can be distributed all over the Internet. If you want
3882   to do that, say Y here and to "IP: multicast routing" below.
3883 
3884 IP: multicast routing
3885 CONFIG_IP_MROUTE
3886   This is used if you want your machine to act as a router for IP
3887   packets that have several destination addresses. It is needed on the
3888   MBONE, a high bandwidth network on top of the Internet which carries
3889   audio and video broadcasts. In order to do that, you would most
3890   likely run the program mrouted. Information about the multicast
3891   capabilities of the various network cards is contained in
3892   Documentation/networking/multicast.txt. If you haven't heard about
3893   it, you don't need it.
3894 
3895 IP: PIM-SM version 1 support
3896 CONFIG_IP_PIMSM_V1
3897   Kernel side support for Sparse Mode PIM (Protocol Independent
3898   Multicast) version 1. This multicast routing protocol is used widely
3899   because Cisco supports it. You need special software to use it
3900   (pimd-v1). Please see http://netweb.usc.edu/pim/ for more
3901   information about PIM.
3902 
3903   Say Y if you want to use PIM-SM v1. Note that you can say N here if
3904   you just want to use Dense Mode PIM.
3905 
3906 IP: PIM-SM version 2 support
3907 CONFIG_IP_PIMSM_V2
3908   Kernel side support for Sparse Mode PIM version 2. In order to use
3909   this, you need an experimental routing daemon supporting it (pimd or
3910   gated-5). This routing protocol is not used widely, so say N unless
3911   you want to play with it.
3912 
3913 PC/TCP compatibility mode
3914 CONFIG_INET_PCTCP
3915   If you have been having difficulties telnetting to your Linux
3916   machine from a DOS system that uses (broken) PC/TCP networking
3917   software (all versions up to OnNet 2.0) over your local Ethernet try
3918   saying Y here. Everyone else says N. 
3919 
3920   People having problems with NCSA telnet should see the file
3921   Documentation/networking/ncsa-telnet.
3922 
3923 Path MTU Discovery (normally enabled)
3924 CONFIG_PATH_MTU_DISCOVERY
3925   MTU (maximal transfer unit) is the size of the chunks we send out
3926   over the net. "Path MTU Discovery" means that, instead of always
3927   sending very small chunks, we start out sending big ones and if we
3928   then discover that some host along the way likes its chunks smaller,
3929   we adjust to a smaller size. This is good, so most people say Y
3930   here.
3931 
3932   However, some DOS software (versions of DOS NCSA telnet and Trumpet
3933   Winsock in PPP mode) is broken and won't be able to connect to your
3934   Linux machine correctly in all cases (especially through a terminal
3935   server) unless you say N here. See
3936   Documentation/networking/ncsa-telnet for the location of fixed NCSA
3937   telnet clients. If in doubt, say Y.
3938 
3939 Disable NAGLE algorithm (normally enabled)
3940 CONFIG_TCP_NAGLE_OFF
3941   The NAGLE algorithm works by requiring an acknowledgment before
3942   sending small IP frames (packets). This keeps tiny telnet and
3943   rlogin packets from congesting Wide Area Networks. Most people
3944   strongly recommend to say N here, thereby leaving NAGLE
3945   enabled. Those programs that would benefit from disabling this
3946   facility can do it on a per connection basis themselves.
3947 
3948 IP: Allow large windows (not recommended if <16 MB of memory)
3949 CONFIG_SKB_LARGE
3950   On high speed, long distance networks the performance limit on
3951   networking becomes the amount of data the sending machine can buffer
3952   until the other end confirms its reception. (At 45 Mbit/second there
3953   are a lot of bits between New York and London ...). If you say Y
3954   here, bigger buffers can be used which allows larger amounts of data
3955   to be "in flight" at any given time. It also means a user process
3956   can require a lot more memory for network buffers and thus this
3957   option is best used only on machines with 16 MB of memory or higher.
3958   Unless you are using long links with end to end speeds of over 2
3959   Mbit a second or satellite links this option will make no difference
3960   to performance.
3961 
3962 Unix domain sockets
3963 CONFIG_UNIX
3964   If you say Y here, you will include support for Unix domain sockets;
3965   sockets are the standard Unix mechanism for establishing and
3966   accessing network connections. Many commonly used programs such as
3967   the X Window system and syslog use these sockets even if your
3968   machine is not connected to any network. Unless you are working on
3969   an embedded system or something similar, you therefore definitely
3970   want to say Y here.
3971 
3972   However, the socket support is also available as a module ( = code
3973   which can be inserted in and removed from the running kernel
3974   whenever you want). If you want to compile it as a module, say M
3975   here and read Documentation/modules.txt. The module will be called
3976   unix.o. If you try building this as a module and you have said Y to
3977   "Kernel module loader support" above, be sure to add 'alias net-pf-1
3978   unix' to your /etc/modules.conf file. Note that several important
3979   services won't work correctly if you say M here and then neglect to
3980   load the module.
3981 
3982   Say Y unless you know what you are doing.
3983 
3984 The IPv6 protocol (EXPERIMENTAL)
3985 CONFIG_IPV6
3986   This is experimental support for the next version of the Internet
3987   Protocol: IP version 6 (also called IPng "IP next generation").
3988   Features of this new protocol include: expanded address space,
3989   authentication and privacy, and seamless interoperability with the
3990   current version of IP (IP version 4). For general information about
3991   IPv6, see http://playground.sun.com/pub/ipng/html/ipng-main.html ;
3992   for specific information about IPv6 under Linux read the HOWTO at
3993   http://www.bieringer.de/linux/IPv6/ and the file net/ipv6/README in
3994   the kernel source.
3995 
3996   If you want to use IPv6, please upgrade to the newest net-tools as
3997   given in Documentation/Changes. You will still be able to do regular
3998   IPv4 networking as well.
3999 
4000   This protocol support is also available as a module ( = code which
4001   can be inserted in and removed from the running kernel whenever you
4002   want). The module will be called ipv6.o. If you want to compile it
4003   as a module, say M here and read Documentation/modules.txt.
4004 
4005   It is safe to say N here for now.
4006 
4007 IPv6: enable EUI-64 token format
4008 CONFIG_IPV6_EUI64
4009   6bone, the network of computers using the IPv6 protocol, is moving
4010   to a new aggregatable address format and a new link local address
4011   assignment (EUI-64). Say Y if your site has upgraded already, or
4012   has started to upgrade.
4013 
4014 IPv6: disable provider based addresses
4015 CONFIG_IPV6_NO_PB
4016   Linux tries to operate correctly when your site has moved to EUI-64
4017   only partially. Unfortunately, the two address formats (old:
4018   "provider based" and new: "aggregatable") are incompatible. Say Y if
4019   your site finished the upgrade to EUI-64, and/or you encountered
4020   some problems caused by the presence of two link-local addresses on
4021   an interface.
4022 
4023 IPv6: routing messages via old netlink
4024 CONFIG_IPV6_NETLINK
4025   You can say Y here to receive routing messages from the IPv6 code
4026   through the old netlink interface. However, a better option is to
4027   say Y to "Kernel/User network link driver" and to "Routing
4028   messages" instead.
4029   
4030 Kernel httpd acceleration (EXPERIMENTAL)
4031 CONFIG_KHTTPD
4032   The kernel httpd acceleration daemon (kHTTPd) is a (limited) web
4033   server built into the kernel. It is limited since it can only serve
4034   files from the file system and cannot deal with executable content
4035   such as CGI scripts. Serving files is sped up if you use kHTTPd.
4036   If kHTTPd is not able to fulfill a request, it can transparently
4037   pass it through to a user space web server such as apache.
4038 
4039   Saying "M" here builds the kHTTPd module; this is NOT enough to have
4040   a working kHTTPd. For safety reasons, the module has to be activated
4041   by doing a "echo 1 > /proc/sys/net/khttpd/start" after inserting the
4042   module.
4043 
4044   Before using this, read the README in net/khttpd !
4045 
4046   The kHTTPd is experimental. Be careful when using it on a production
4047   machine. Also note that kHTTPd doesn't support virtual servers yet.
4048 
4049 IPX networking
4050 CONFIG_IPX
4051   This is support for the Novell networking protocol, IPX, commonly
4052   used for local networks of Windows machines. You need it if you want
4053   to access Novell NetWare file or print servers using the Linux
4054   Novell client ncpfs (available from
4055   ftp://metalab.unc.edu/pub/Linux/system/filesystems/ ) or from within
4056   the Linux DOS emulator DOSEMU (read the DOSEMU-HOWTO, available from
4057   http://www.linuxdoc.org/docs.html#howto ). In order to do the
4058   former, you'll also have to say Y to "NCP file system support",
4059   below.
4060 
4061   IPX is similar in scope to IP, while SPX, which runs on top of IPX,
4062   is similar to TCP. There is also experimental support for SPX in
4063   Linux (see "SPX networking", below).
4064 
4065   To turn your Linux box into a fully featured NetWare file server and
4066   IPX router, say Y here and fetch either lwared from
4067   ftp://metalab.unc.edu/pub/Linux/system/network/daemons/ or mars_nwe
4068   from ftp://ftp.gwdg.de/pub/linux/misc/ncpfs . For more information,
4069   read the IPX-HOWTO available from
4070   http://www.linuxdoc.org/docs.html#howto .
4071 
4072   General information about how to connect Linux, Windows machines and
4073   Macs is on the WWW at http://www.eats.com/linux_mac_win.html .
4074 
4075   The IPX driver would enlarge your kernel by about 16 KB. This driver
4076   is also available as a module ( = code which can be inserted in and
4077   removed from the running kernel whenever you want). The module will
4078   be called ipx.o. If you want to compile it as a module, say M here
4079   and read Documentation/modules.txt. Unless you want to integrate
4080   your Linux box with a local Novell network, say N.
4081 
4082 IPX: Full internal IPX network
4083 CONFIG_IPX_INTERN
4084   Every IPX network has an address that identifies it. Sometimes it is
4085   useful to give an IPX "network" address to your Linux box as well
4086   (for example if your box is acting as a file server for different
4087   IPX networks: it will then be accessible from everywhere using the
4088   same address). The way this is done is to create a virtual internal
4089   "network" inside your box and to assign an IPX address to this
4090   network. Say Y here if you want to do this; read the IPX-HOWTO at
4091   http://www.linuxdoc.org/docs.html#howto for details.
4092 
4093   The full internal IPX network enables you to allocate sockets on
4094   different virtual nodes of the internal network. This is done by
4095   evaluating the field sipx_node of the socket address given to the
4096   bind call. So applications should always initialize the node field
4097   to 0 when binding a socket on the primary network. In this case the
4098   socket is assigned the default node that has been given to the
4099   kernel when the internal network was created. By enabling the full
4100   internal IPX network the cross-forwarding of packets targeted at
4101   'special' sockets to sockets listening on the primary network is
4102   disabled. This might break existing applications, especially RIP/SAP
4103   daemons. A RIP/SAP daemon that works well with the full internal net
4104   can be found on ftp://ftp.gwdg.de/pub/linux/misc/ncpfs . 
4105 
4106   If you don't know what you are doing, say N.
4107 
4108 IPX: SPX networking (EXPERIMENTAL)
4109 CONFIG_SPX
4110   The Sequenced Packet eXchange protocol is a transport layer protocol
4111   built on top of IPX. It is used in Novell NetWare systems for
4112   client-server applications and is similar to TCP (which runs on top
4113   of IP).
4114 
4115   Note that Novell NetWare file sharing does not use SPX; it uses a
4116   protocol called NCP, for which separate Linux support is available
4117   ("NCP file system support" below for the client side, and the user
4118   space programs lwared or mars_nwe for the server side).
4119 
4120   Say Y here if you have use for SPX; read the IPX-HOWTO at
4121   http://www.linuxdoc.org/docs.html#howto for details.
4122 
4123   This driver is also available as a module ( = code which can be
4124   inserted in and removed from the running kernel whenever you want).
4125   The module will be called af_spx.o. If you want to compile it as a
4126   module, say M here and read Documentation/modules.txt.
4127 
4128 DECnet networking (EXPERIMENTAL)
4129 CONFIG_DECNET
4130   The DECnet networking protocol was used in many products made by
4131   Digital (now Compaq). It provides reliable stream and sequenced
4132   packet communications over which run a variety of services similar
4133   to those which run over TCP/IP.
4134 
4135   To find some tools to use with the kernel layer support, please
4136   look at Patrick Caulfield's web site: 
4137   http://linux.dreamtime.org/decnet/
4138 
4139   More detailed documentation is available in the
4140   Documentation/networking/decnet.txt file.
4141 
4142   Be sure to say Y to "/proc file system support" and "Sysctl support"
4143   below when using DECnet, since you will need sysctl support to aid
4144   in configuration at run time.
4145 
4146   The DECnet code is also available as a module ( = code which can be
4147   inserted in and removed from the running kernel whenever you want).
4148   The module is called decnet.o.
4149 
4150 DECnet SIOCFIGCONF support
4151 CONFIG_DECNET_SIOCGIFCONF
4152    This option should only be turned on if you are really sure that
4153    you know what you are doing. It can break other applications which
4154    use this system call and the proper way to get the information
4155    provided by this call is to use rtnetlink.
4156    
4157    If unsure, say N.
4158 
4159 DECnet Router Support (EXPERIMENTAL)
4160 CONFIG_DECNET_ROUTER
4161    Add support for turning your DECnet Endnode into a level 1 or 2
4162    router. This is an unfinished option for developers only. If you do
4163    say Y here, then make sure that you also say Y to "Kernel/User
4164    network link driver", "Routing messages" and "Network packet
4165    filtering". The first two are required to allow configuration via
4166    rtnetlink (currently you need Alexey Kuznetsov's iproute2 package
4167    from ftp://ftp.inr.ac.ru). The "Network packet filtering" option
4168    will be required for the forthcoming routing daemon to work.
4169 
4170    See Documentation/networking/decnet.txt for more information.
4171 
4172 DECnet: use FWMARK value as routing key
4173 CONFIG_DECNET_ROUTE_FWMARK
4174   If you say Y here, you will be able to specify different routes for
4175   packets with different FWMARK ("firewalling mark") values
4176   (see ipchains(8), "-m" argument).
4177 
4178 Appletalk interfaces support
4179 CONFIG_APPLETALK
4180   AppleTalk is the way Apple computers speak to each other on a
4181   network. If your Linux box is connected to such a network and you
4182   want to join the conversation, say Y.
4183 
4184 AppleTalk protocol support
4185 CONFIG_ATALK
4186   AppleTalk is the way Apple computers speak to each other on a
4187   network. If your Linux box is connected to such a network and you
4188   want to join the conversation, say Y. You will need to use the
4189   netatalk package so that your Linux box can act as a print and file
4190   server for Macs as well as access AppleTalk printers. Check out
4191   http://threepio.hitchcock.org/cgi-bin/faq/netatalk/faq.pl on the WWW
4192   for details. EtherTalk is the name used for AppleTalk over Ethernet
4193   and the cheaper and slower LocalTalk is AppleTalk over a proprietary
4194   Apple network using serial links. EtherTalk and LocalTalk are fully
4195   supported by Linux.
4196 
4197   General information about how to connect Linux, Windows machines and
4198   Macs is on the WWW at http://www.eats.com/linux_mac_win.html . The
4199   NET-3-HOWTO, available from
4200   http://www.linuxdoc.org/docs.html#howto , contains valuable
4201   information as well.
4202 
4203   This driver is also available as a module ( = code which can be
4204   inserted in and removed from the running kernel whenever you want).
4205   The module is called appletalk.o. If you want to compile it as a
4206   module, say M here and read Documentation/modules.txt. I hear that
4207   the GNU boycott of Apple is over, so even politically correct people
4208   are allowed to say Y here.
4209 
4210 AppleTalk-IP driver support
4211 CONFIG_IPDDP
4212   This allows IP networking for users who only have AppleTalk
4213   networking available. This feature is experimental. With this
4214   driver, you can encapsulate IP inside AppleTalk (e.g. if your Linux
4215   box is stuck on an AppleTalk only network) or decapsulate (e.g. if
4216   you want your Linux box to act as an Internet gateway for a zoo of
4217   AppleTalk connected Macs). Please see the file
4218   Documentation/networking/ipddp.txt for more information.
4219 
4220   If you say Y here, the AppleTalk-IP support will be compiled into
4221   the kernel. In this case, you can either use encapsulation or
4222   decapsulation, but not both. With the following two questions, you
4223   decide which one you want.
4224 
4225   If you say M here, the AppleTalk-IP support will be compiled as a
4226   module ( = code which can be inserted in and removed from the
4227   running kernel whenever you want, read Documentation/modules.txt).
4228   The module is called ipddp.o. In this case, you will be able to use
4229   both encapsulation and decapsulation simultaneously, by loading two
4230   copies of the module and specifying different values for the module
4231   option ipddp_mode. 
4232 
4233 IP to AppleTalk-IP Encapsulation support
4234 CONFIG_IPDDP_ENCAP
4235   If you say Y here, the AppleTalk-IP code will be able to encapsulate
4236   IP packets inside AppleTalk frames; this is useful if your Linux box
4237   is stuck on an AppleTalk network (which hopefully contains a
4238   decapsulator somewhere). Please see
4239   Documentation/networking/ipddp.txt for more information. If you said
4240   Y to "AppleTalk-IP driver support" above and you say Y here, then
4241   you cannot say Y to "AppleTalk-IP to IP Decapsulation support",
4242   below.
4243 
4244 AppleTalk-IP to IP Decapsulation support
4245 CONFIG_IPDDP_DECAP
4246   If you say Y here, the AppleTalk-IP code will be able to decapsulate
4247   AppleTalk-IP frames to IP packets; this is useful if you want your
4248   Linux box to act as an Internet gateway for an AppleTalk network.
4249   Please see Documentation/networking/ipddp.txt for more information.
4250   If you said Y to "AppleTalk-IP driver support" above and you say Y
4251   here, then you cannot say Y to "IP to AppleTalk-IP Encapsulation
4252   support", above.
4253 
4254 Apple/Farallon LocalTalk PC card support
4255 CONFIG_LTPC
4256   This allows you to use the AppleTalk PC card to connect to LocalTalk
4257   networks. The card is also known as the Farallon PhoneNet PC card.
4258   If you are in doubt, this card is the one with the 65C02 chip on it.
4259   You also need version 1.3.3 or later of the netatalk package.
4260   This driver is experimental, which means that it may not work.
4261   See the file Documentation/networking/ltpc.txt.
4262 
4263 COPS LocalTalk PC card support
4264 CONFIG_COPS
4265   This allows you to use COPS AppleTalk cards to connect to LocalTalk
4266   networks. You also need version 1.3.3 or later of the netatalk
4267   package. This driver is experimental, which means that it may not
4268   work. This driver will only work if you choose "AppleTalk DDP"
4269   networking support, above.
4270   Please read the file Documentation/networking/cops.txt. 
4271 
4272 Dayna firmware support
4273 CONFIG_COPS_DAYNA
4274   Support COPS compatible cards with Dayna style firmware (Dayna
4275   DL2000/ Daynatalk/PC (half length), COPS LT-95, Farallon PhoneNET PC
4276   III, Farallon PhoneNET PC II).
4277 
4278 Tangent firmware support
4279 CONFIG_COPS_TANGENT
4280   Support COPS compatible cards with Tangent style firmware (Tangent
4281   ATB_II, Novell NL-1000, Daystar Digital LT-200.
4282 
4283 Amateur Radio support
4284 CONFIG_HAMRADIO
4285   If you want to connect your Linux box to an amateur radio, answer Y
4286   here. You want to read http://www.tapr.org/tapr/html/pkthome.html
4287   and the HAM-HOWTO and the AX25-HOWTO, both available from
4288   http://www.linuxdoc.org/docs.html#howto .
4289 
4290   Note that the answer to this question won't directly affect the
4291   kernel: saying N will just cause this configure script to skip all
4292   the questions about amateur radio.
4293 
4294 Amateur Radio AX.25 Level 2
4295 CONFIG_AX25
4296   This is the protocol used for computer communication over amateur
4297   radio. It is either used by itself for point-to-point links, or to
4298   carry other protocols such as tcp/ip. To use it, you need a device
4299   that connects your Linux box to your amateur radio. You can either
4300   use a low speed TNC (a Terminal Node Controller acts as a kind of
4301   modem connecting your computer's serial port to your radio's
4302   microphone input and speaker output) supporting the KISS protocol or
4303   one of the various SCC cards that are supported by the generic Z8530
4304   or the DMA SCC driver. Another option are the Baycom modem serial
4305   and parallel port hacks or the sound card modem (supported by their
4306   own drivers). If you say Y here, you also have to say Y to one of
4307   those drivers.
4308 
4309   Information about where to get supporting software for Linux amateur
4310   radio as well as information about how to configure an AX.25 port is
4311   contained in the AX25-HOWTO, available from
4312   http://www.linuxdoc.org/docs.html#howto . You might also want to
4313   check out the file Documentation/networking/ax25.txt in the kernel
4314   source. More information about digital amateur radio in general is
4315   on the WWW at http://www.tapr.org/tapr/html/pkthome.html .
4316 
4317   This driver is also available as a module ( = code which can be
4318   inserted in and removed from the running kernel whenever you want).
4319   The module will be called ax25.o. If you want to compile it as a
4320   module, say M here and read Documentation/modules.txt.
4321 
4322 AX.25 DAMA Slave support
4323 CONFIG_AX25_DAMA_SLAVE
4324   DAMA is a mechanism to prevent collisions when doing AX.25
4325   networking. A DAMA server (called "master") accepts incoming traffic
4326   from clients (called "slaves") and redistributes it to other slaves.
4327   If you say Y here, your Linux box will act as a DAMA slave; this is
4328   transparent in that you don't have to do any special DAMA
4329   configuration. (Linux cannot yet act as a DAMA server.) If unsure,
4330   say N.
4331 
4332 AX.25 DAMA Master support
4333 CONFIG_AX25_DAMA_MASTER
4334   DAMA is a mechanism to prevent collisions when doing AX.25
4335   networking. A DAMA server (called "master") accepts incoming traffic
4336   from clients (called "slaves") and redistributes it to other
4337   slaves. If you say Y here, your Linux box will act as a DAMA server.
4338   If unsure, say N.
4339 
4340 Amateur Radio NET/ROM
4341 CONFIG_NETROM
4342   NET/ROM is a network layer protocol on top of AX.25 useful for
4343   routing.
4344 
4345   A comprehensive listing of all the software for Linux amateur radio
4346   users as well as information about how to configure an AX.25 port is
4347   contained in the AX25-HOWTO, available from
4348   http://www.linuxdoc.org/docs.html#howto . You also might want to
4349   check out the file Documentation/networking/ax25.txt. More
4350   information about digital amateur radio in general is on the WWW at
4351   http://www.tapr.org/tapr/html/pkthome.html .
4352 
4353   This driver is also available as a module ( = code which can be
4354   inserted in and removed from the running kernel whenever you want).
4355   The module will be called netrom.o. If you want to compile it as a
4356   module, say M here and read Documentation/modules.txt.
4357 
4358 Amateur Radio X.25 PLP (Rose)
4359 CONFIG_ROSE
4360   The Packet Layer Protocol (PLP) is a way to route packets over X.25
4361   connections in general and amateur radio AX.25 connections in
4362   particular, essentially an alternative to NET/ROM.
4363 
4364   A comprehensive listing of all the software for Linux amateur radio
4365   users as well as information about how to configure an AX.25 port is
4366   contained in the AX25-HOWTO, available from
4367   http://www.linuxdoc.org/docs.html#howto . You also might want to
4368   check out the file Documentation/networking/ax25.txt. More
4369   information about digital amateur radio in general is on the WWW at
4370   http://www.tapr.org/tapr/html/pkthome.html .
4371 
4372   This driver is also available as a module ( = code which can be
4373   inserted in and removed from the running kernel whenever you want).
4374   The module will be called rose.o. If you want to compile it as a
4375   module, say M here and read Documentation/modules.txt.
4376 
4377 Serial port KISS driver for AX.25
4378 CONFIG_MKISS
4379   KISS is a protocol used for the exchange of data between a computer
4380   and a Terminal Node Controller (a small embedded system commonly
4381   used for networking over AX.25 amateur radio connections; it
4382   connects the computer's serial port with the radio's microphone
4383   input and speaker output).
4384 
4385   Although KISS is less advanced than the 6pack protocol, it has
4386   the advantage that it is already supported by most modern TNCs
4387   without the need for a firmware upgrade.
4388 
4389   If you want to compile this driver as a module ( = code which can be
4390   inserted in and removed from the running kernel whenever you want),
4391   say M here and read Documentation/modules.txt. The module will be
4392   called mkiss.o.
4393 
4394 Serial port 6PACK driver for AX.25
4395 CONFIG_6PACK
4396   6pack is a transmission protocol for the data exchange between your
4397   PC and your TNC (the Terminal Node Controller acts as a kind of
4398   modem connecting your computer's serial port to your radio's
4399   microphone input and speaker output). This protocol can be used as
4400   an alternative to KISS for networking over AX.25 amateur radio
4401   connections, but it has some extended functionality.
4402 
4403   Note that this driver is still experimental and might cause
4404   problems. For details about the features and the usage of the
4405   driver, read Documentation/networking/6pack.txt.
4406 
4407   If you want to compile this driver as a module ( = code which can be
4408   inserted in and removed from the running kernel whenever you want),
4409   say M here and read Documentation/modules.txt. The module will be
4410   called 6pack.o.
4411 
4412 BPQ Ethernet driver
4413 CONFIG_BPQETHER
4414   AX.25 is the protocol used for computer communication over amateur
4415   radio. If you say Y here, you will be able to send and receive AX.25
4416   traffic over Ethernet (also called "BPQ AX.25"), which could be
4417   useful if some other computer on your local network has a direct
4418   amateur radio connection.
4419 
4420 High-speed (DMA) SCC driver for AX.25
4421 CONFIG_DMASCC
4422   This is a driver for high-speed SCC boards, i.e. those supporting
4423   DMA on one port. You usually use those boards to connect your
4424   computer to an amateur radio modem (such as the WA4DSY 56kbps
4425   modem), in order to send and receive AX.25 packet radio network
4426   traffic.
4427 
4428   Currently, this driver supports Ottawa PI/PI2, Paccomm/Gracilis
4429   PackeTwin, and S5SCC/DMA boards. They are detected automatically.
4430   If you have one of these cards, say Y here and read the AX25-HOWTO,
4431   available from http://www.linuxdoc.org/docs.html#howto .
4432 
4433   This driver can operate multiple boards simultaneously. If you
4434   compile it as a module (by saying M instead of Y), it will be called
4435   dmascc.o. If you don't pass any parameter to the driver, all
4436   possible I/O addresses are probed. This could irritate other devices
4437   that are currently not in use. You may specify the list of addresses
4438   to be probed by "dmascc=addr1,addr2,..." (when compiled into the
4439   kernel image) or "io=addr1,addr2,..." (when loaded as a module). The
4440   network interfaces will be called dmascc0 and dmascc1 for the board
4441   detected first, dmascc2 and dmascc3 for the second one, and so on.
4442 
4443   Before you configure each interface with ifconfig, you MUST set
4444   certain parameters, such as channel access timing, clock mode, and
4445   DMA channel. This is accomplished with a small utility program,
4446   dmascc_cfg, available at
4447   http://www.nt.tuwien.ac.at/~kkudielk/Linux/ . Please be sure to get
4448   at least version 1.27 of dmascc_cfg, as older versions will not
4449   work with the current driver.
4450 
4451 Z8530 SCC driver for AX.25
4452 CONFIG_SCC
4453   These cards are used to connect your Linux box to an amateur radio
4454   in order to communicate with other computers. If you want to use
4455   this, read Documentation/networking/z8530drv.txt and the AX25-HOWTO,
4456   available from http://www.linuxdoc.org/docs.html#howto . Also
4457   make sure to say Y to "Amateur Radio AX.25 Level 2" support.
4458 
4459   If you want to compile this as a module ( = code which can be
4460   inserted in and removed from the running kernel whenever you want),
4461   say M here and read Documentation/modules.txt. The module will be
4462   called scc.o.
4463 
4464 additional delay for PA0HZP OptoSCC compatible boards
4465 CONFIG_SCC_DELAY
4466   Say Y here if you experience problems with the SCC driver not
4467   working properly; please read Documentation/networking/z8530drv.txt
4468   for details. If unsure, say N.
4469 
4470 #support for TRX that feedback the tx signal to rx
4471 #CONFIG_SCC_TRXECHO
4472 ###
4473 ### Don't know what's going on here.
4474 ###
4475 #
4476 
4477 YAM driver for AX.25
4478 CONFIG_YAM
4479   The YAM is a modem for packet radio which connects to the serial
4480   port and includes some of the functions of a Terminal Node
4481   Controller. If you have one of those, say Y here.
4482 
4483   If you want to compile this as a module ( = code which can be
4484   inserted in and removed from the running kernel whenever you want),
4485   say M here and read Documentation/modules.txt.
4486 
4487 BAYCOM picpar and par96 driver for AX.25
4488 CONFIG_BAYCOM_PAR
4489   This is a driver for Baycom style simple amateur radio modems that
4490   connect to a parallel interface. The driver supports the picpar and
4491   par96 designs. To configure the driver, use the sethdlc utility
4492   available in the standard ax25 utilities package. For information on
4493   the modems, see http://www.baycom.de and the file
4494   Documentation/networking/baycom.txt.
4495 
4496   If you want to compile this driver as a module ( = code which can be
4497   inserted in and removed from the running kernel whenever you want),
4498   say M here and read Documentation/modules.txt. This is recommended.
4499   The module will be called baycom_par.o.
4500 
4501 BAYCOM EPP driver for AX.25
4502 CONFIG_BAYCOM_EPP
4503   This is a driver for Baycom style simple