2 # For a description of the syntax of this configuration file,
3 # see Documentation/kbuild/kconfig-language.txt.
6 mainmenu "Linux Kernel Configuration"
12 This is Linux's home port. Linux was originally native to the Intel
13 386, and runs on all the later x86 processors including the Intel
14 486, 586, Pentiums, and various instruction-set-compatible chips by
15 AMD, Cyrix, and others.
17 config SEMAPHORE_SLEEPERS
32 config GENERIC_ISA_DMA
40 config GENERIC_HWEIGHT
44 config ARCH_MAY_HAVE_PC_FDC
54 menu "Processor type and features"
57 bool "Symmetric multi-processing support"
59 This enables support for systems with more than one CPU. If you have
60 a system with only one CPU, like most personal computers, say N. If
61 you have a system with more than one CPU, say Y.
63 If you say N here, the kernel will run on single and multiprocessor
64 machines, but will use only one CPU of a multiprocessor machine. If
65 you say Y here, the kernel will run on many, but not all,
66 singleprocessor machines. On a singleprocessor machine, the kernel
67 will run faster if you say N here.
69 Note that if you say Y here and choose architecture "586" or
70 "Pentium" under "Processor family", the kernel will not work on 486
71 architectures. Similarly, multiprocessor kernels for the "PPro"
72 architecture may not work on all Pentium based boards.
74 People using multiprocessor machines who say Y here should also say
75 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
76 Management" code will be disabled if you say Y here.
78 See also the <file:Documentation/smp.txt>,
79 <file:Documentation/i386/IO-APIC.txt>,
80 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
81 <http://www.tldp.org/docs.html#howto>.
83 If you don't know what to do here, say N.
86 prompt "Subarchitecture Type"
92 Choose this option if your computer is a standard PC or compatible.
97 Select this for an AMD Elan processor.
99 Do not use this option for K6/Athlon/Opteron processors!
101 If unsure, choose "PC-compatible" instead.
106 Voyager is an MCA-based 32-way capable SMP architecture proprietary
107 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
111 If you do not specifically know you have a Voyager based machine,
112 say N here, otherwise the kernel you build will not be bootable.
115 bool "NUMAQ (IBM/Sequent)"
119 This option is used for getting Linux to run on a (IBM/Sequent) NUMA
120 multiquad box. This changes the way that processors are bootstrapped,
121 and uses Clustered Logical APIC addressing mode instead of Flat Logical.
122 You will need a new lynxer.elf file to flash your firmware with - send
123 email to <Martin.Bligh@us.ibm.com>.
126 bool "Summit/EXA (IBM x440)"
129 This option is needed for IBM systems that use the Summit/EXA chipset.
130 In particular, it is needed for the x440.
132 If you don't have one of these computers, you should say N here.
135 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
138 This option is needed for the systems that have more than 8 CPUs
139 and if the system is not of any sub-arch type above.
141 If you don't have such a system, you should say N here.
144 bool "SGI 320/540 (Visual Workstation)"
146 The SGI Visual Workstation series is an IA32-based workstation
147 based on SGI systems chips with some legacy PC hardware attached.
149 Say Y here to create a kernel to run on the SGI 320 or 540.
151 A kernel compiled for the Visual Workstation will not run on PCs
152 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
154 config X86_GENERICARCH
155 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
158 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
159 It is intended for a generic binary kernel.
162 bool "Support for Unisys ES7000 IA32 series"
165 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
166 supposed to run on an IA32-based Unisys ES7000 system.
167 Only choose this option if you have such a system, otherwise you
175 depends on NUMA && (X86_SUMMIT || X86_GENERICARCH)
178 config HAVE_ARCH_PARSE_SRAT
183 config X86_SUMMIT_NUMA
186 depends on NUMA && (X86_SUMMIT || X86_GENERICARCH)
188 config X86_CYCLONE_TIMER
191 depends on X86_SUMMIT || X86_GENERICARCH
193 config ES7000_CLUSTERED_APIC
196 depends on SMP && X86_ES7000 && MPENTIUMIII
198 source "arch/i386/Kconfig.cpu"
201 bool "HPET Timer Support"
203 This enables the use of the HPET for the kernel's internal timer.
204 HPET is the next generation timer replacing legacy 8254s.
205 You can safely choose Y here. However, HPET will only be
206 activated if the platform and the BIOS support this feature.
207 Otherwise the 8254 will be used for timing services.
209 Choose N to continue using the legacy 8254 timer.
211 config HPET_EMULATE_RTC
213 depends on HPET_TIMER && RTC=y
217 int "Maximum number of CPUs (2-255)"
220 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
223 This allows you to specify the maximum number of CPUs which this
224 kernel will support. The maximum supported value is 255 and the
225 minimum value which makes sense is 2.
227 This is purely to save memory - each supported CPU adds
228 approximately eight kilobytes to the kernel image.
231 bool "SMT (Hyperthreading) scheduler support"
234 SMT scheduler support improves the CPU scheduler's decision making
235 when dealing with Intel Pentium 4 chips with HyperThreading at a
236 cost of slightly increased overhead in some places. If unsure say
240 bool "Multi-core scheduler support"
244 Multi-core scheduler support improves the CPU scheduler's decision
245 making when dealing with multi-core CPU chips at a cost of slightly
246 increased overhead in some places. If unsure say N here.
248 source "kernel/Kconfig.preempt"
251 bool "Local APIC support on uniprocessors"
252 depends on !SMP && !(X86_VISWS || X86_VOYAGER)
254 A local APIC (Advanced Programmable Interrupt Controller) is an
255 integrated interrupt controller in the CPU. If you have a single-CPU
256 system which has a processor with a local APIC, you can say Y here to
257 enable and use it. If you say Y here even though your machine doesn't
258 have a local APIC, then the kernel will still run with no slowdown at
259 all. The local APIC supports CPU-generated self-interrupts (timer,
260 performance counters), and the NMI watchdog which detects hard
264 bool "IO-APIC support on uniprocessors"
265 depends on X86_UP_APIC
267 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
268 SMP-capable replacement for PC-style interrupt controllers. Most
269 SMP systems and many recent uniprocessor systems have one.
271 If you have a single-CPU system with an IO-APIC, you can say Y here
272 to use it. If you say Y here even though your machine doesn't have
273 an IO-APIC, then the kernel will still run with no slowdown at all.
275 config X86_LOCAL_APIC
277 depends on X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER)
282 depends on X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER))
285 config X86_VISWS_APIC
291 bool "Machine Check Exception"
292 depends on !X86_VOYAGER
294 Machine Check Exception support allows the processor to notify the
295 kernel if it detects a problem (e.g. overheating, component failure).
296 The action the kernel takes depends on the severity of the problem,
297 ranging from a warning message on the console, to halting the machine.
298 Your processor must be a Pentium or newer to support this - check the
299 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
300 have a design flaw which leads to false MCE events - hence MCE is
301 disabled on all P5 processors, unless explicitly enabled with "mce"
302 as a boot argument. Similarly, if MCE is built in and creates a
303 problem on some new non-standard machine, you can boot with "nomce"
304 to disable it. MCE support simply ignores non-MCE processors like
305 the 386 and 486, so nearly everyone can say Y here.
307 config X86_MCE_NONFATAL
308 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
311 Enabling this feature starts a timer that triggers every 5 seconds which
312 will look at the machine check registers to see if anything happened.
313 Non-fatal problems automatically get corrected (but still logged).
314 Disable this if you don't want to see these messages.
315 Seeing the messages this option prints out may be indicative of dying hardware,
316 or out-of-spec (ie, overclocked) hardware.
317 This option only does something on certain CPUs.
318 (AMD Athlon/Duron and Intel Pentium 4)
320 config X86_MCE_P4THERMAL
321 bool "check for P4 thermal throttling interrupt."
322 depends on X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
324 Enabling this feature will cause a message to be printed when the P4
325 enters thermal throttling.
329 bool "Enable VM86 support" if EMBEDDED
331 This option is required by programs like DOSEMU to run 16-bit legacy
332 code on X86 processors. It also may be needed by software like
333 XFree86 to initialize some video cards via BIOS. Disabling this
334 option saves about 6k.
337 tristate "Toshiba Laptop support"
339 This adds a driver to safely access the System Management Mode of
340 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
341 not work on models with a Phoenix BIOS. The System Management Mode
342 is used to set the BIOS and power saving options on Toshiba portables.
344 For information on utilities to make use of this driver see the
345 Toshiba Linux utilities web site at:
346 <http://www.buzzard.org.uk/toshiba/>.
348 Say Y if you intend to run this kernel on a Toshiba portable.
352 tristate "Dell laptop support"
354 This adds a driver to safely access the System Management Mode
355 of the CPU on the Dell Inspiron 8000. The System Management Mode
356 is used to read cpu temperature and cooling fan status and to
357 control the fans on the I8K portables.
359 This driver has been tested only on the Inspiron 8000 but it may
360 also work with other Dell laptops. You can force loading on other
361 models by passing the parameter `force=1' to the module. Use at
364 For information on utilities to make use of this driver see the
365 I8K Linux utilities web site at:
366 <http://people.debian.org/~dz/i8k/>
368 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
371 config X86_REBOOTFIXUPS
372 bool "Enable X86 board specific fixups for reboot"
376 This enables chipset and/or board specific fixups to be done
377 in order to get reboot to work correctly. This is only needed on
378 some combinations of hardware and BIOS. The symptom, for which
379 this config is intended, is when reboot ends with a stalled/hung
382 Currently, the only fixup is for the Geode GX1/CS5530A/TROM2.1.
385 Say Y if you want to enable the fixup. Currently, it's safe to
386 enable this option even if you don't need it.
390 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
392 If you say Y here and also to "/dev file system support" in the
393 'File systems' section, you will be able to update the microcode on
394 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
395 Pentium III, Pentium 4, Xeon etc. You will obviously need the
396 actual microcode binary data itself which is not shipped with the
399 For latest news and information on obtaining all the required
400 ingredients for this driver, check:
401 <http://www.urbanmyth.org/microcode/>.
403 To compile this driver as a module, choose M here: the
404 module will be called microcode.
407 tristate "/dev/cpu/*/msr - Model-specific register support"
409 This device gives privileged processes access to the x86
410 Model-Specific Registers (MSRs). It is a character device with
411 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
412 MSR accesses are directed to a specific CPU on multi-processor
416 tristate "/dev/cpu/*/cpuid - CPU information support"
418 This device gives processes access to the x86 CPUID instruction to
419 be executed on a specific processor. It is a character device
420 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
423 source "drivers/firmware/Kconfig"
426 prompt "High Memory Support"
431 depends on !X86_NUMAQ
433 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
434 However, the address space of 32-bit x86 processors is only 4
435 Gigabytes large. That means that, if you have a large amount of
436 physical memory, not all of it can be "permanently mapped" by the
437 kernel. The physical memory that's not permanently mapped is called
440 If you are compiling a kernel which will never run on a machine with
441 more than 1 Gigabyte total physical RAM, answer "off" here (default
442 choice and suitable for most users). This will result in a "3GB/1GB"
443 split: 3GB are mapped so that each process sees a 3GB virtual memory
444 space and the remaining part of the 4GB virtual memory space is used
445 by the kernel to permanently map as much physical memory as
448 If the machine has between 1 and 4 Gigabytes physical RAM, then
451 If more than 4 Gigabytes is used then answer "64GB" here. This
452 selection turns Intel PAE (Physical Address Extension) mode on.
453 PAE implements 3-level paging on IA32 processors. PAE is fully
454 supported by Linux, PAE mode is implemented on all recent Intel
455 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
456 then the kernel will not boot on CPUs that don't support PAE!
458 The actual amount of total physical memory will either be
459 auto detected or can be forced by using a kernel command line option
460 such as "mem=256M". (Try "man bootparam" or see the documentation of
461 your boot loader (lilo or loadlin) about how to pass options to the
462 kernel at boot time.)
464 If unsure, say "off".
468 depends on !X86_NUMAQ
470 Select this if you have a 32-bit processor and between 1 and 4
471 gigabytes of physical RAM.
475 depends on X86_CMPXCHG64
477 Select this if you have a 32-bit processor and more than 4
478 gigabytes of physical RAM.
483 depends on EXPERIMENTAL && !X86_PAE
484 prompt "Memory split" if EMBEDDED
487 Select the desired split between kernel and user memory.
489 If the address range available to the kernel is less than the
490 physical memory installed, the remaining memory will be available
491 as "high memory". Accessing high memory is a little more costly
492 than low memory, as it needs to be mapped into the kernel first.
493 Note that increasing the kernel address space limits the range
494 available to user programs, making the address space there
495 tighter. Selecting anything other than the default 3G/1G split
496 will also likely make your kernel incompatible with binary-only
499 If you are not absolutely sure what you are doing, leave this
503 bool "3G/1G user/kernel split"
504 config VMSPLIT_3G_OPT
505 bool "3G/1G user/kernel split (for full 1G low memory)"
507 bool "2G/2G user/kernel split"
509 bool "1G/3G user/kernel split"
514 default 0xB0000000 if VMSPLIT_3G_OPT
515 default 0x78000000 if VMSPLIT_2G
516 default 0x40000000 if VMSPLIT_1G
521 depends on HIGHMEM64G || HIGHMEM4G
526 depends on HIGHMEM64G
529 # Common NUMA Features
531 bool "Numa Memory Allocation and Scheduler Support"
532 depends on SMP && HIGHMEM64G && (X86_NUMAQ || X86_GENERICARCH || (X86_SUMMIT && ACPI))
534 default y if (X86_NUMAQ || X86_SUMMIT)
536 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
537 depends on X86_SUMMIT && (!HIGHMEM64G || !ACPI)
541 default "4" if X86_NUMAQ
543 depends on NEED_MULTIPLE_NODES
545 config HAVE_ARCH_BOOTMEM_NODE
550 config ARCH_HAVE_MEMORY_PRESENT
552 depends on DISCONTIGMEM
555 config NEED_NODE_MEMMAP_SIZE
557 depends on DISCONTIGMEM || SPARSEMEM
560 config HAVE_ARCH_ALLOC_REMAP
565 config ARCH_FLATMEM_ENABLE
567 depends on (ARCH_SELECT_MEMORY_MODEL && X86_PC)
569 config ARCH_DISCONTIGMEM_ENABLE
573 config ARCH_DISCONTIGMEM_DEFAULT
577 config ARCH_SPARSEMEM_ENABLE
579 depends on (NUMA || (X86_PC && EXPERIMENTAL))
580 select SPARSEMEM_STATIC
582 config ARCH_SELECT_MEMORY_MODEL
584 depends on ARCH_SPARSEMEM_ENABLE
588 config HAVE_ARCH_EARLY_PFN_TO_NID
594 bool "Allocate 3rd-level pagetables from highmem"
595 depends on HIGHMEM4G || HIGHMEM64G
597 The VM uses one page table entry for each page of physical memory.
598 For systems with a lot of RAM, this can be wasteful of precious
599 low memory. Setting this option will put user-space page table
600 entries in high memory.
602 config MATH_EMULATION
603 bool "Math emulation"
605 Linux can emulate a math coprocessor (used for floating point
606 operations) if you don't have one. 486DX and Pentium processors have
607 a math coprocessor built in, 486SX and 386 do not, unless you added
608 a 487DX or 387, respectively. (The messages during boot time can
609 give you some hints here ["man dmesg"].) Everyone needs either a
610 coprocessor or this emulation.
612 If you don't have a math coprocessor, you need to say Y here; if you
613 say Y here even though you have a coprocessor, the coprocessor will
614 be used nevertheless. (This behavior can be changed with the kernel
615 command line option "no387", which comes handy if your coprocessor
616 is broken. Try "man bootparam" or see the documentation of your boot
617 loader (lilo or loadlin) about how to pass options to the kernel at
618 boot time.) This means that it is a good idea to say Y here if you
619 intend to use this kernel on different machines.
621 More information about the internals of the Linux math coprocessor
622 emulation can be found in <file:arch/i386/math-emu/README>.
624 If you are not sure, say Y; apart from resulting in a 66 KB bigger
625 kernel, it won't hurt.
628 bool "MTRR (Memory Type Range Register) support"
630 On Intel P6 family processors (Pentium Pro, Pentium II and later)
631 the Memory Type Range Registers (MTRRs) may be used to control
632 processor access to memory ranges. This is most useful if you have
633 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
634 allows bus write transfers to be combined into a larger transfer
635 before bursting over the PCI/AGP bus. This can increase performance
636 of image write operations 2.5 times or more. Saying Y here creates a
637 /proc/mtrr file which may be used to manipulate your processor's
638 MTRRs. Typically the X server should use this.
640 This code has a reasonably generic interface so that similar
641 control registers on other processors can be easily supported
644 The Cyrix 6x86, 6x86MX and M II processors have Address Range
645 Registers (ARRs) which provide a similar functionality to MTRRs. For
646 these, the ARRs are used to emulate the MTRRs.
647 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
648 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
649 write-combining. All of these processors are supported by this code
650 and it makes sense to say Y here if you have one of them.
652 Saying Y here also fixes a problem with buggy SMP BIOSes which only
653 set the MTRRs for the boot CPU and not for the secondary CPUs. This
654 can lead to all sorts of problems, so it's good to say Y here.
656 You can safely say Y even if your machine doesn't have MTRRs, you'll
657 just add about 9 KB to your kernel.
659 See <file:Documentation/mtrr.txt> for more information.
662 bool "Boot from EFI support (EXPERIMENTAL)"
666 This enables the the kernel to boot on EFI platforms using
667 system configuration information passed to it from the firmware.
668 This also enables the kernel to use any EFI runtime services that are
669 available (such as the EFI variable services).
671 This option is only useful on systems that have EFI firmware
672 and will result in a kernel image that is ~8k larger. In addition,
673 you must use the latest ELILO loader available at
674 <http://elilo.sourceforge.net> in order to take advantage of
675 kernel initialization using EFI information (neither GRUB nor LILO know
676 anything about EFI). However, even with this option, the resultant
677 kernel should continue to boot on existing non-EFI platforms.
680 bool "Enable kernel irq balancing"
681 depends on SMP && X86_IO_APIC
684 The default yes will allow the kernel to do irq load balancing.
685 Saying no will keep the kernel from doing irq load balancing.
687 # turning this on wastes a bunch of space.
688 # Summit needs it only when NUMA is on
691 depends on (((X86_SUMMIT || X86_GENERICARCH) && NUMA) || (X86 && EFI))
695 bool "Use register arguments"
698 Compile the kernel with -mregparm=3. This instructs gcc to use
699 a more efficient function call ABI which passes the first three
700 arguments of a function call via registers, which results in denser
703 If this option is disabled, then the default ABI of passing
704 arguments via the stack is used.
709 bool "Enable seccomp to safely compute untrusted bytecode"
713 This kernel feature is useful for number crunching applications
714 that may need to compute untrusted bytecode during their
715 execution. By using pipes or other transports made available to
716 the process as file descriptors supporting the read/write
717 syscalls, it's possible to isolate those applications in
718 their own address space using seccomp. Once seccomp is
719 enabled via /proc/<pid>/seccomp, it cannot be disabled
720 and the task is only allowed to execute a few safe syscalls
721 defined by each seccomp mode.
723 If unsure, say Y. Only embedded should say N here.
725 source kernel/Kconfig.hz
728 bool "kexec system call (EXPERIMENTAL)"
729 depends on EXPERIMENTAL
731 kexec is a system call that implements the ability to shutdown your
732 current kernel, and to start another kernel. It is like a reboot
733 but it is indepedent of the system firmware. And like a reboot
734 you can start any kernel with it, not just Linux.
736 The name comes from the similiarity to the exec system call.
738 It is an ongoing process to be certain the hardware in a machine
739 is properly shutdown, so do not be surprised if this code does not
740 initially work for you. It may help to enable device hotplugging
741 support. As of this writing the exact hardware interface is
742 strongly in flux, so no good recommendation can be made.
745 bool "kernel crash dumps (EXPERIMENTAL)"
746 depends on EXPERIMENTAL
749 Generate crash dump after being started by kexec.
751 config PHYSICAL_START
752 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
754 default "0x1000000" if CRASH_DUMP
757 This gives the physical address where the kernel is loaded. Normally
758 for regular kernels this value is 0x100000 (1MB). But in the case
759 of kexec on panic the fail safe kernel needs to run at a different
760 address than the panic-ed kernel. This option is used to set the load
761 address for kernels used to capture crash dump on being kexec'ed
762 after panic. The default value for crash dump kernels is
763 0x1000000 (16MB). This can also be set based on the "X" value as
764 specified in the "crashkernel=YM@XM" command line boot parameter
765 passed to the panic-ed kernel. Typically this parameter is set as
766 crashkernel=64M@16M. Please take a look at
767 Documentation/kdump/kdump.txt for more details about crash dumps.
769 Don't change this unless you know what you are doing.
772 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
773 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
775 Say Y here to experiment with turning CPUs off and on, and to
776 enable suspend on SMP systems. CPUs can be controlled through
777 /sys/devices/system/cpu.
783 menu "Power management options (ACPI, APM)"
784 depends on !X86_VOYAGER
786 source kernel/power/Kconfig
788 source "drivers/acpi/Kconfig"
790 menu "APM (Advanced Power Management) BIOS Support"
791 depends on PM && !X86_VISWS
794 tristate "APM (Advanced Power Management) BIOS support"
797 APM is a BIOS specification for saving power using several different
798 techniques. This is mostly useful for battery powered laptops with
799 APM compliant BIOSes. If you say Y here, the system time will be
800 reset after a RESUME operation, the /proc/apm device will provide
801 battery status information, and user-space programs will receive
802 notification of APM "events" (e.g. battery status change).
804 If you select "Y" here, you can disable actual use of the APM
805 BIOS by passing the "apm=off" option to the kernel at boot time.
807 Note that the APM support is almost completely disabled for
808 machines with more than one CPU.
810 In order to use APM, you will need supporting software. For location
811 and more information, read <file:Documentation/pm.txt> and the
812 Battery Powered Linux mini-HOWTO, available from
813 <http://www.tldp.org/docs.html#howto>.
815 This driver does not spin down disk drives (see the hdparm(8)
816 manpage ("man 8 hdparm") for that), and it doesn't turn off
817 VESA-compliant "green" monitors.
819 This driver does not support the TI 4000M TravelMate and the ACER
820 486/DX4/75 because they don't have compliant BIOSes. Many "green"
821 desktop machines also don't have compliant BIOSes, and this driver
822 may cause those machines to panic during the boot phase.
824 Generally, if you don't have a battery in your machine, there isn't
825 much point in using this driver and you should say N. If you get
826 random kernel OOPSes or reboots that don't seem to be related to
827 anything, try disabling/enabling this option (or disabling/enabling
830 Some other things you should try when experiencing seemingly random,
833 1) make sure that you have enough swap space and that it is
835 2) pass the "no-hlt" option to the kernel
836 3) switch on floating point emulation in the kernel and pass
837 the "no387" option to the kernel
838 4) pass the "floppy=nodma" option to the kernel
839 5) pass the "mem=4M" option to the kernel (thereby disabling
840 all but the first 4 MB of RAM)
841 6) make sure that the CPU is not over clocked.
842 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
843 8) disable the cache from your BIOS settings
844 9) install a fan for the video card or exchange video RAM
845 10) install a better fan for the CPU
846 11) exchange RAM chips
847 12) exchange the motherboard.
849 To compile this driver as a module, choose M here: the
850 module will be called apm.
852 config APM_IGNORE_USER_SUSPEND
853 bool "Ignore USER SUSPEND"
856 This option will ignore USER SUSPEND requests. On machines with a
857 compliant APM BIOS, you want to say N. However, on the NEC Versa M
858 series notebooks, it is necessary to say Y because of a BIOS bug.
861 bool "Enable PM at boot time"
864 Enable APM features at boot time. From page 36 of the APM BIOS
865 specification: "When disabled, the APM BIOS does not automatically
866 power manage devices, enter the Standby State, enter the Suspend
867 State, or take power saving steps in response to CPU Idle calls."
868 This driver will make CPU Idle calls when Linux is idle (unless this
869 feature is turned off -- see "Do CPU IDLE calls", below). This
870 should always save battery power, but more complicated APM features
871 will be dependent on your BIOS implementation. You may need to turn
872 this option off if your computer hangs at boot time when using APM
873 support, or if it beeps continuously instead of suspending. Turn
874 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
875 T400CDT. This is off by default since most machines do fine without
879 bool "Make CPU Idle calls when idle"
882 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
883 On some machines, this can activate improved power savings, such as
884 a slowed CPU clock rate, when the machine is idle. These idle calls
885 are made after the idle loop has run for some length of time (e.g.,
886 333 mS). On some machines, this will cause a hang at boot time or
887 whenever the CPU becomes idle. (On machines with more than one CPU,
888 this option does nothing.)
890 config APM_DISPLAY_BLANK
891 bool "Enable console blanking using APM"
894 Enable console blanking using the APM. Some laptops can use this to
895 turn off the LCD backlight when the screen blanker of the Linux
896 virtual console blanks the screen. Note that this is only used by
897 the virtual console screen blanker, and won't turn off the backlight
898 when using the X Window system. This also doesn't have anything to
899 do with your VESA-compliant power-saving monitor. Further, this
900 option doesn't work for all laptops -- it might not turn off your
901 backlight at all, or it might print a lot of errors to the console,
902 especially if you are using gpm.
904 config APM_RTC_IS_GMT
905 bool "RTC stores time in GMT"
908 Say Y here if your RTC (Real Time Clock a.k.a. hardware clock)
909 stores the time in GMT (Greenwich Mean Time). Say N if your RTC
912 It is in fact recommended to store GMT in your RTC, because then you
913 don't have to worry about daylight savings time changes. The only
914 reason not to use GMT in your RTC is if you also run a broken OS
915 that doesn't understand GMT.
917 config APM_ALLOW_INTS
918 bool "Allow interrupts during APM BIOS calls"
921 Normally we disable external interrupts while we are making calls to
922 the APM BIOS as a measure to lessen the effects of a badly behaving
923 BIOS implementation. The BIOS should reenable interrupts if it
924 needs to. Unfortunately, some BIOSes do not -- especially those in
925 many of the newer IBM Thinkpads. If you experience hangs when you
926 suspend, try setting this to Y. Otherwise, say N.
928 config APM_REAL_MODE_POWER_OFF
929 bool "Use real mode APM BIOS call to power off"
932 Use real mode APM BIOS calls to switch off the computer. This is
933 a work-around for a number of buggy BIOSes. Switch this option on if
934 your computer crashes instead of powering off properly.
938 source "arch/i386/kernel/cpu/cpufreq/Kconfig"
942 menu "Bus options (PCI, PCMCIA, EISA, MCA, ISA)"
945 bool "PCI support" if !X86_VISWS
946 depends on !X86_VOYAGER
947 default y if X86_VISWS
949 Find out whether you have a PCI motherboard. PCI is the name of a
950 bus system, i.e. the way the CPU talks to the other stuff inside
951 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
952 VESA. If you have PCI, say Y, otherwise N.
954 The PCI-HOWTO, available from
955 <http://www.tldp.org/docs.html#howto>, contains valuable
956 information about which PCI hardware does work under Linux and which
960 prompt "PCI access mode"
961 depends on PCI && !X86_VISWS
964 On PCI systems, the BIOS can be used to detect the PCI devices and
965 determine their configuration. However, some old PCI motherboards
966 have BIOS bugs and may crash if this is done. Also, some embedded
967 PCI-based systems don't have any BIOS at all. Linux can also try to
968 detect the PCI hardware directly without using the BIOS.
970 With this option, you can specify how Linux should detect the
971 PCI devices. If you choose "BIOS", the BIOS will be used,
972 if you choose "Direct", the BIOS won't be used, and if you
973 choose "MMConfig", then PCI Express MMCONFIG will be used.
974 If you choose "Any", the kernel will try MMCONFIG, then the
975 direct access method and falls back to the BIOS if that doesn't
976 work. If unsure, go with the default, which is "Any".
981 config PCI_GOMMCONFIG
994 depends on !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
999 depends on PCI && ((PCI_GODIRECT || PCI_GOANY) || X86_VISWS)
1004 depends on PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1007 source "drivers/pci/pcie/Kconfig"
1009 source "drivers/pci/Kconfig"
1017 depends on !(X86_VOYAGER || X86_VISWS)
1019 Find out whether you have ISA slots on your motherboard. ISA is the
1020 name of a bus system, i.e. the way the CPU talks to the other stuff
1021 inside your box. Other bus systems are PCI, EISA, MicroChannel
1022 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1023 newer boards don't support it. If you have ISA, say Y, otherwise N.
1029 The Extended Industry Standard Architecture (EISA) bus was
1030 developed as an open alternative to the IBM MicroChannel bus.
1032 The EISA bus provided some of the features of the IBM MicroChannel
1033 bus while maintaining backward compatibility with cards made for
1034 the older ISA bus. The EISA bus saw limited use between 1988 and
1035 1995 when it was made obsolete by the PCI bus.
1037 Say Y here if you are building a kernel for an EISA-based machine.
1041 source "drivers/eisa/Kconfig"
1044 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1045 default y if X86_VOYAGER
1047 MicroChannel Architecture is found in some IBM PS/2 machines and
1048 laptops. It is a bus system similar to PCI or ISA. See
1049 <file:Documentation/mca.txt> (and especially the web page given
1050 there) before attempting to build an MCA bus kernel.
1052 source "drivers/mca/Kconfig"
1055 tristate "NatSemi SCx200 support"
1056 depends on !X86_VOYAGER
1058 This provides basic support for the National Semiconductor SCx200
1059 processor. Right now this is just a driver for the GPIO pins.
1061 If you don't know what to do here, say N.
1063 This support is also available as a module. If compiled as a
1064 module, it will be called scx200.
1068 depends on AGP_AMD64
1070 source "drivers/pcmcia/Kconfig"
1072 source "drivers/pci/hotplug/Kconfig"
1076 menu "Executable file formats"
1078 source "fs/Kconfig.binfmt"
1082 source "net/Kconfig"
1084 source "drivers/Kconfig"
1088 menu "Instrumentation Support"
1089 depends on EXPERIMENTAL
1091 source "arch/i386/oprofile/Kconfig"
1094 bool "Kprobes (EXPERIMENTAL)"
1095 depends on EXPERIMENTAL && MODULES
1097 Kprobes allows you to trap at almost any kernel address and
1098 execute a callback function. register_kprobe() establishes
1099 a probepoint and specifies the callback. Kprobes is useful
1100 for kernel debugging, non-intrusive instrumentation and testing.
1101 If in doubt, say "N".
1104 source "arch/i386/Kconfig.debug"
1106 source "security/Kconfig"
1108 source "crypto/Kconfig"
1110 source "lib/Kconfig"
1113 # Use the generic interrupt handling code in kernel/irq/:
1115 config GENERIC_HARDIRQS
1119 config GENERIC_IRQ_PROBE
1123 config GENERIC_PENDING_IRQ
1125 depends on GENERIC_HARDIRQS && SMP
1130 depends on SMP && !X86_VOYAGER
1135 depends on SMP && !(X86_VISWS || X86_VOYAGER)
1138 config X86_BIOS_REBOOT
1140 depends on !(X86_VISWS || X86_VOYAGER)
1143 config X86_TRAMPOLINE
1145 depends on X86_SMP || (X86_VOYAGER && SMP)
projects / linux-2.6 / blob