2 # For a description of the syntax of this configuration file,
3 # see Documentation/kbuild/kconfig-language.txt.
6 mainmenu "Linux Kernel Configuration"
12 The ARM series is a line of low-power-consumption RISC chip designs
13 licensed by ARM Ltd and targeted at embedded applications and
14 handhelds such as the Compaq IPAQ. ARM-based PCs are no longer
15 manufactured, but legacy ARM-based PC hardware remains popular in
16 Europe. There is an ARM Linux project with a web page at
17 <http://www.arm.linux.org.uk/>.
26 The Extended Industry Standard Architecture (EISA) bus was
27 developed as an open alternative to the IBM MicroChannel bus.
29 The EISA bus provided some of the features of the IBM MicroChannel
30 bus while maintaining backward compatibility with cards made for
31 the older ISA bus. The EISA bus saw limited use between 1988 and
32 1995 when it was made obsolete by the PCI bus.
34 Say Y here if you are building a kernel for an EISA-based machine.
44 MicroChannel Architecture is found in some IBM PS/2 machines and
45 laptops. It is a bus system similar to PCI or ISA. See
46 <file:Documentation/mca.txt> (and especially the web page given
47 there) before attempting to build an MCA bus kernel.
49 config RWSEM_GENERIC_SPINLOCK
53 config RWSEM_XCHGADD_ALGORITHM
56 config GENERIC_CALIBRATE_DELAY
60 config GENERIC_BUST_SPINLOCK
63 config ARCH_MAY_HAVE_PC_FDC
66 config GENERIC_ISA_DMA
80 prompt "ARM system type"
81 default ARCH_VERSATILE
84 bool "Cirrus-CL-PS7500FE"
88 Support for the Cirrus Logic PS7500FE system-on-a-chip.
91 bool "CLPS711x/EP721x-based"
93 Support for Cirrus Logic 711x/721x based boards.
98 select FOOTBRIDGE_ADDIN
100 Support for Intel's EBSA285 companion chip.
106 This is an evaluation board for the StrongARM processor available
107 from Digital. It has limited hardware on-board, including an
108 Ethernet interface, two PCMCIA sockets, two serial ports and a
116 This enables support for the Cirrus EP93xx series of CPUs.
118 config ARCH_FOOTBRIDGE
122 Support for systems based on the DC21285 companion chip
123 ("FootBridge"), such as the Simtec CATS and the Rebel NetWinder.
125 config ARCH_INTEGRATOR
130 Support for ARM's Integrator platform.
136 Support for Intel's IOP3XX (XScale) family of processors.
143 Support for Intel's IXP4XX (XScale) family of processors.
146 bool "IXP2400/2800-based"
149 Support for Intel's IXP2400/2800 (XScale) family of processors.
155 Say Y here if you intend to run this kernel on a LinkUp Systems
156 L7200 Software Development Board which uses an ARM720T processor.
157 Information on this board can be obtained at:
159 <http://www.linkupsys.com/>
161 If you have any questions or comments about the Linux kernel port
162 to this board, send e-mail to <sjhill@cotw.com>.
168 Support for Intel's PXA2XX processor line.
175 select ARCH_MAY_HAVE_PC_FDC
178 On the Acorn Risc-PC, Linux can support the internal IDE disk and
179 CD-ROM interface, serial and parallel port, and the floppy drive.
184 select ARCH_DISCONTIGMEM_ENABLE
187 Support for StrongARM 11x0 based boards.
190 bool "Samsung S3C2410"
192 Samsung S3C2410X CPU based systems, such as the Simtec Electronics
193 BAST (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or
194 the Samsung SMDK2410 development board (and derivatives).
202 Support for the StrongARM based Digital DNARD machine, also known
203 as "Shark" (<http://www.shark-linux.de/shark.html>).
208 Say Y here for systems based on one of the Sharp LH7A40X
209 System on a Chip processors. These CPUs include an ARM922T
210 core with a wide array of integrated devices for
211 hand-held and low-power applications.
216 Support for TI's OMAP platform (OMAP1 and OMAP2).
218 config ARCH_VERSATILE
224 This enables support for ARM Ltd Versatile board.
231 This enables support for ARM Ltd RealView boards.
236 Support for Motorola's i.MX family of processors (MX1, MXL).
239 bool "Hynix-HMS720x-based"
242 This enables support for systems based on the Hynix HMS720x
245 bool "Agilent AAEC-2000 based"
248 This enables support for systems based on the Agilent AAEC-2000
250 config ARCH_AT91RM9200
253 Say Y here if you intend to run this kernel on an Atmel
254 AT91RM9200-based board.
258 source "arch/arm/mach-clps711x/Kconfig"
260 source "arch/arm/mach-ep93xx/Kconfig"
262 source "arch/arm/mach-footbridge/Kconfig"
264 source "arch/arm/mach-integrator/Kconfig"
266 source "arch/arm/mach-iop3xx/Kconfig"
268 source "arch/arm/mach-ixp4xx/Kconfig"
270 source "arch/arm/mach-ixp2000/Kconfig"
272 source "arch/arm/mach-pxa/Kconfig"
274 source "arch/arm/mach-sa1100/Kconfig"
276 source "arch/arm/plat-omap/Kconfig"
278 source "arch/arm/mach-omap1/Kconfig"
280 source "arch/arm/mach-omap2/Kconfig"
282 source "arch/arm/mach-s3c2410/Kconfig"
284 source "arch/arm/mach-lh7a40x/Kconfig"
286 source "arch/arm/mach-imx/Kconfig"
288 source "arch/arm/mach-h720x/Kconfig"
290 source "arch/arm/mach-versatile/Kconfig"
292 source "arch/arm/mach-aaec2000/Kconfig"
294 source "arch/arm/mach-realview/Kconfig"
296 source "arch/arm/mach-at91rm9200/Kconfig"
298 # Definitions to make life easier
302 source arch/arm/mm/Kconfig
304 # bool 'Use XScale PMU as timer source' CONFIG_XSCALE_PMU_TIMER
307 depends on CPU_XSCALE && !XSCALE_PMU_TIMER
312 source "arch/arm/common/Kconfig"
314 config FORCE_MAX_ZONEORDER
327 Find out whether you have ISA slots on your motherboard. ISA is the
328 name of a bus system, i.e. the way the CPU talks to the other stuff
329 inside your box. Other bus systems are PCI, EISA, MicroChannel
330 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
331 newer boards don't support it. If you have ISA, say Y, otherwise N.
333 # Select ISA DMA controller support
338 # Select ISA DMA interface
343 bool "PCI support" if ARCH_INTEGRATOR_AP || ARCH_VERSATILE_PB
345 Find out whether you have a PCI motherboard. PCI is the name of a
346 bus system, i.e. the way the CPU talks to the other stuff inside
347 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
348 VESA. If you have PCI, say Y, otherwise N.
350 The PCI-HOWTO, available from
351 <http://www.tldp.org/docs.html#howto>, contains valuable
352 information about which PCI hardware does work under Linux and which
355 # Select the host bridge type
356 config PCI_HOST_VIA82C505
358 depends on PCI && ARCH_SHARK
361 source "drivers/pci/Kconfig"
363 source "drivers/pcmcia/Kconfig"
367 menu "Kernel Features"
370 bool "Symmetric Multi-Processing (EXPERIMENTAL)"
371 depends on EXPERIMENTAL && REALVIEW_MPCORE
373 This enables support for systems with more than one CPU. If you have
374 a system with only one CPU, like most personal computers, say N. If
375 you have a system with more than one CPU, say Y.
377 If you say N here, the kernel will run on single and multiprocessor
378 machines, but will use only one CPU of a multiprocessor machine. If
379 you say Y here, the kernel will run on many, but not all, single
380 processor machines. On a single processor machine, the kernel will
381 run faster if you say N here.
383 See also the <file:Documentation/smp.txt>,
384 <file:Documentation/i386/IO-APIC.txt>,
385 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
386 <http://www.linuxdoc.org/docs.html#howto>.
388 If you don't know what to do here, say N.
391 int "Maximum number of CPUs (2-32)"
397 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
398 depends on SMP && HOTPLUG && EXPERIMENTAL
400 Say Y here to experiment with turning CPUs off and on. CPUs
401 can be controlled through /sys/devices/system/cpu.
404 bool "Use local timer interrupts"
405 depends on SMP && REALVIEW_MPCORE
408 Enable support for local timers on SMP platforms, rather then the
409 legacy IPI broadcast method. Local timers allows the system
410 accounting to be spread across the timer interval, preventing a
411 "thundering herd" at every timer tick.
414 bool "Preemptible Kernel (EXPERIMENTAL)"
415 depends on EXPERIMENTAL
417 This option reduces the latency of the kernel when reacting to
418 real-time or interactive events by allowing a low priority process to
419 be preempted even if it is in kernel mode executing a system call.
420 This allows applications to run more reliably even when the system is
423 Say Y here if you are building a kernel for a desktop, embedded
424 or real-time system. Say N if you are unsure.
427 bool "Dynamic tick timer"
429 Select this option if you want to disable continuous timer ticks
430 and have them programmed to occur as required. This option saves
431 power as the system can remain in idle state for longer.
433 By default dynamic tick is disabled during the boot, and can be
434 manually enabled with:
436 echo 1 > /sys/devices/system/timer/timer0/dyn_tick
438 Alternatively, if you want dynamic tick automatically enabled
439 during boot, pass "dyntick=enable" via the kernel command string.
441 Please note that dynamic tick may affect the accuracy of
442 timekeeping on some platforms depending on the implementation.
443 Currently at least OMAP, PXA2xx and SA11x0 platforms are known
444 to have accurate timekeeping with dynamic tick.
448 default 128 if ARCH_L7200
449 default 200 if ARCH_EBSA110 || ARCH_S3C2410
450 default OMAP_32K_TIMER_HZ if ARCH_OMAP && OMAP_32K_TIMER
454 bool "Use the ARM EABI to compile the kernel"
456 This option allows for the kernel to be compiled using the latest
457 ARM ABI (aka EABI). This is only useful if you are using a user
458 space environment that is also compiled with EABI.
460 Since there are major incompatibilities between the legacy ABI and
461 EABI, especially with regard to structure member alignment, this
462 option also changes the kernel syscall calling convention to
463 disambiguate both ABIs and allow for backward compatibility support
464 (selected with CONFIG_OABI_COMPAT).
466 To use this you need GCC version 4.0.0 or later.
469 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
470 depends on AEABI && EXPERIMENTAL
473 This option preserves the old syscall interface along with the
474 new (ARM EABI) one. It also provides a compatibility layer to
475 intercept syscalls that have structure arguments which layout
476 in memory differs between the legacy ABI and the new ARM EABI
477 (only for non "thumb" binaries). This option adds a tiny
478 overhead to all syscalls and produces a slightly larger kernel.
479 If you know you'll be using only pure EABI user space then you
480 can say N here. If this option is not selected and you attempt
481 to execute a legacy ABI binary then the result will be
482 UNPREDICTABLE (in fact it can be predicted that it won't work
483 at all). If in doubt say Y.
485 config ARCH_DISCONTIGMEM_ENABLE
487 default (ARCH_LH7A40X && !LH7A40X_CONTIGMEM)
489 Say Y to support efficient handling of discontiguous physical memory,
490 for architectures which are either NUMA (Non-Uniform Memory Access)
491 or have huge holes in the physical address space for other reasons.
492 See <file:Documentation/vm/numa> for more.
497 bool "Timer and CPU usage LEDs"
498 depends on ARCH_CDB89712 || ARCH_CO285 || ARCH_EBSA110 || \
499 ARCH_EBSA285 || ARCH_IMX || ARCH_INTEGRATOR || \
500 ARCH_LUBBOCK || MACH_MAINSTONE || ARCH_NETWINDER || \
501 ARCH_OMAP || ARCH_P720T || ARCH_PXA_IDP || \
502 ARCH_SA1100 || ARCH_SHARK || ARCH_VERSATILE || \
505 If you say Y here, the LEDs on your machine will be used
506 to provide useful information about your current system status.
508 If you are compiling a kernel for a NetWinder or EBSA-285, you will
509 be able to select which LEDs are active using the options below. If
510 you are compiling a kernel for the EBSA-110 or the LART however, the
511 red LED will simply flash regularly to indicate that the system is
512 still functional. It is safe to say Y here if you have a CATS
513 system, but the driver will do nothing.
516 bool "Timer LED" if (!ARCH_CDB89712 && !ARCH_OMAP) || \
517 MACH_OMAP_H2 || MACH_OMAP_PERSEUS2
519 default y if ARCH_EBSA110
521 If you say Y here, one of the system LEDs (the green one on the
522 NetWinder, the amber one on the EBSA285, or the red one on the LART)
523 will flash regularly to indicate that the system is still
524 operational. This is mainly useful to kernel hackers who are
525 debugging unstable kernels.
527 The LART uses the same LED for both Timer LED and CPU usage LED
528 functions. You may choose to use both, but the Timer LED function
529 will overrule the CPU usage LED.
532 bool "CPU usage LED" if (!ARCH_CDB89712 && !ARCH_EBSA110 && \
533 !ARCH_OMAP) || MACH_OMAP_H2 || MACH_OMAP_PERSEUS2
536 If you say Y here, the red LED will be used to give a good real
537 time indication of CPU usage, by lighting whenever the idle task
538 is not currently executing.
540 The LART uses the same LED for both Timer LED and CPU usage LED
541 functions. You may choose to use both, but the Timer LED function
542 will overrule the CPU usage LED.
544 config ALIGNMENT_TRAP
546 default y if !ARCH_EBSA110
548 ARM processors can not fetch/store information which is not
549 naturally aligned on the bus, i.e., a 4 byte fetch must start at an
550 address divisible by 4. On 32-bit ARM processors, these non-aligned
551 fetch/store instructions will be emulated in software if you say
552 here, which has a severe performance impact. This is necessary for
553 correct operation of some network protocols. With an IP-only
554 configuration it is safe to say N, otherwise say Y.
560 # Compressed boot loader in ROM. Yes, we really want to ask about
561 # TEXT and BSS so we preserve their values in the config files.
562 config ZBOOT_ROM_TEXT
563 hex "Compressed ROM boot loader base address"
566 The physical address at which the ROM-able zImage is to be
567 placed in the target. Platforms which normally make use of
568 ROM-able zImage formats normally set this to a suitable
569 value in their defconfig file.
571 If ZBOOT_ROM is not enabled, this has no effect.
574 hex "Compressed ROM boot loader BSS address"
577 The base address of 64KiB of read/write memory in the target
578 for the ROM-able zImage, which must be available while the
579 decompressor is running. Platforms which normally make use of
580 ROM-able zImage formats normally set this to a suitable
581 value in their defconfig file.
583 If ZBOOT_ROM is not enabled, this has no effect.
586 bool "Compressed boot loader in ROM/flash"
587 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
589 Say Y here if you intend to execute your compressed kernel image
590 (zImage) directly from ROM or flash. If unsure, say N.
593 string "Default kernel command string"
596 On some architectures (EBSA110 and CATS), there is currently no way
597 for the boot loader to pass arguments to the kernel. For these
598 architectures, you should supply some command-line options at build
599 time by entering them here. As a minimum, you should specify the
600 memory size and the root device (e.g., mem=64M root=/dev/nfs).
603 bool "Kernel Execute-In-Place from ROM"
604 depends on !ZBOOT_ROM
606 Execute-In-Place allows the kernel to run from non-volatile storage
607 directly addressable by the CPU, such as NOR flash. This saves RAM
608 space since the text section of the kernel is not loaded from flash
609 to RAM. Read-write sections, such as the data section and stack,
610 are still copied to RAM. The XIP kernel is not compressed since
611 it has to run directly from flash, so it will take more space to
612 store it. The flash address used to link the kernel object files,
613 and for storing it, is configuration dependent. Therefore, if you
614 say Y here, you must know the proper physical address where to
615 store the kernel image depending on your own flash memory usage.
617 Also note that the make target becomes "make xipImage" rather than
618 "make zImage" or "make Image". The final kernel binary to put in
619 ROM memory will be arch/arm/boot/xipImage.
624 hex "XIP Kernel Physical Location"
625 depends on XIP_KERNEL
628 This is the physical address in your flash memory the kernel will
629 be linked for and stored to. This address is dependent on your
634 if (ARCH_SA1100 || ARCH_INTEGRATOR || ARCH_OMAP1)
636 menu "CPU Frequency scaling"
638 source "drivers/cpufreq/Kconfig"
640 config CPU_FREQ_SA1100
642 depends on CPU_FREQ && (SA1100_H3100 || SA1100_H3600 || SA1100_H3800 || SA1100_LART || SA1100_PLEB || SA1100_BADGE4 || SA1100_HACKKIT)
645 config CPU_FREQ_SA1110
647 depends on CPU_FREQ && (SA1100_ASSABET || SA1100_CERF || SA1100_PT_SYSTEM3)
650 config CPU_FREQ_INTEGRATOR
651 tristate "CPUfreq driver for ARM Integrator CPUs"
652 depends on ARCH_INTEGRATOR && CPU_FREQ
655 This enables the CPUfreq driver for ARM Integrator CPUs.
657 For details, take a look at <file:Documentation/cpu-freq>.
665 menu "Floating point emulation"
667 comment "At least one emulation must be selected"
670 bool "NWFPE math emulation"
671 depends on !AEABI || OABI_COMPAT
673 Say Y to include the NWFPE floating point emulator in the kernel.
674 This is necessary to run most binaries. Linux does not currently
675 support floating point hardware so you need to say Y here even if
676 your machine has an FPA or floating point co-processor podule.
678 You may say N here if you are going to load the Acorn FPEmulator
682 bool "Support extended precision"
685 Say Y to include 80-bit support in the kernel floating-point
686 emulator. Otherwise, only 32 and 64-bit support is compiled in.
687 Note that gcc does not generate 80-bit operations by default,
688 so in most cases this option only enlarges the size of the
689 floating point emulator without any good reason.
691 You almost surely want to say N here.
694 bool "FastFPE math emulation (EXPERIMENTAL)"
695 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3 && EXPERIMENTAL
697 Say Y here to include the FAST floating point emulator in the kernel.
698 This is an experimental much faster emulator which now also has full
699 precision for the mantissa. It does not support any exceptions.
700 It is very simple, and approximately 3-6 times faster than NWFPE.
702 It should be sufficient for most programs. It may be not suitable
703 for scientific calculations, but you have to check this for yourself.
704 If you do not feel you need a faster FP emulation you should better
708 bool "VFP-format floating point maths"
709 depends on CPU_V6 || CPU_ARM926T
711 Say Y to include VFP support code in the kernel. This is needed
712 if your hardware includes a VFP unit.
714 Please see <file:Documentation/arm/VFP/release-notes.txt> for
715 release notes and additional status information.
717 Say N if your target does not have VFP hardware.
721 menu "Userspace binary formats"
723 source "fs/Kconfig.binfmt"
726 tristate "RISC OS personality"
729 Say Y here to include the kernel code necessary if you want to run
730 Acorn RISC OS/Arthur binaries under Linux. This code is still very
731 experimental; if this sounds frightening, say N and sleep in peace.
732 You can also say M here to compile this support as a module (which
733 will be called arthur).
737 menu "Power management options"
739 source "kernel/power/Kconfig"
742 tristate "Advanced Power Management Emulation"
744 APM is a BIOS specification for saving power using several different
745 techniques. This is mostly useful for battery powered laptops with
746 APM compliant BIOSes. If you say Y here, the system time will be
747 reset after a RESUME operation, the /proc/apm device will provide
748 battery status information, and user-space programs will receive
749 notification of APM "events" (e.g. battery status change).
751 In order to use APM, you will need supporting software. For location
752 and more information, read <file:Documentation/pm.txt> and the
753 Battery Powered Linux mini-HOWTO, available from
754 <http://www.tldp.org/docs.html#howto>.
756 This driver does not spin down disk drives (see the hdparm(8)
757 manpage ("man 8 hdparm") for that), and it doesn't turn off
758 VESA-compliant "green" monitors.
760 Generally, if you don't have a battery in your machine, there isn't
761 much point in using this driver and you should say N. If you get
762 random kernel OOPSes or reboots that don't seem to be related to
763 anything, try disabling/enabling this option (or disabling/enabling
770 menu "Device Drivers"
772 source "drivers/base/Kconfig"
774 source "drivers/connector/Kconfig"
777 source "drivers/mtd/Kconfig"
780 source "drivers/parport/Kconfig"
782 source "drivers/pnp/Kconfig"
784 source "drivers/block/Kconfig"
786 source "drivers/acorn/block/Kconfig"
788 if PCMCIA || ARCH_CLPS7500 || ARCH_IOP3XX || ARCH_IXP4XX \
789 || ARCH_L7200 || ARCH_LH7A40X || ARCH_PXA || ARCH_RPC \
790 || ARCH_S3C2410 || ARCH_SA1100 || ARCH_SHARK || FOOTBRIDGE
791 source "drivers/ide/Kconfig"
794 source "drivers/scsi/Kconfig"
796 source "drivers/md/Kconfig"
798 source "drivers/message/fusion/Kconfig"
800 source "drivers/ieee1394/Kconfig"
802 source "drivers/message/i2o/Kconfig"
804 source "drivers/net/Kconfig"
806 source "drivers/isdn/Kconfig"
808 # input before char - char/joystick depends on it. As does USB.
810 source "drivers/input/Kconfig"
812 source "drivers/char/Kconfig"
814 source "drivers/i2c/Kconfig"
816 source "drivers/spi/Kconfig"
818 source "drivers/w1/Kconfig"
820 source "drivers/hwmon/Kconfig"
822 #source "drivers/l3/Kconfig"
824 source "drivers/misc/Kconfig"
826 source "drivers/mfd/Kconfig"
828 source "drivers/media/Kconfig"
830 source "drivers/video/Kconfig"
832 source "sound/Kconfig"
834 source "drivers/usb/Kconfig"
836 source "drivers/mmc/Kconfig"
842 source "arch/arm/oprofile/Kconfig"
844 source "arch/arm/Kconfig.debug"
846 source "security/Kconfig"
848 source "crypto/Kconfig"