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"
235 SMT scheduler support improves the CPU scheduler's decision making
236 when dealing with Intel Pentium 4 chips with HyperThreading at a
237 cost of slightly increased overhead in some places. If unsure say
241 bool "Multi-core scheduler support"
245 Multi-core scheduler support improves the CPU scheduler's decision
246 making when dealing with multi-core CPU chips at a cost of slightly
247 increased overhead in some places. If unsure say N here.
249 source "kernel/Kconfig.preempt"
252 bool "Local APIC support on uniprocessors"
253 depends on !SMP && !(X86_VISWS || X86_VOYAGER)
255 A local APIC (Advanced Programmable Interrupt Controller) is an
256 integrated interrupt controller in the CPU. If you have a single-CPU
257 system which has a processor with a local APIC, you can say Y here to
258 enable and use it. If you say Y here even though your machine doesn't
259 have a local APIC, then the kernel will still run with no slowdown at
260 all. The local APIC supports CPU-generated self-interrupts (timer,
261 performance counters), and the NMI watchdog which detects hard
265 bool "IO-APIC support on uniprocessors"
266 depends on X86_UP_APIC
268 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
269 SMP-capable replacement for PC-style interrupt controllers. Most
270 SMP systems and many recent uniprocessor systems have one.
272 If you have a single-CPU system with an IO-APIC, you can say Y here
273 to use it. If you say Y here even though your machine doesn't have
274 an IO-APIC, then the kernel will still run with no slowdown at all.
276 config X86_LOCAL_APIC
278 depends on X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER)
283 depends on X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER))
286 config X86_VISWS_APIC
292 bool "Machine Check Exception"
293 depends on !X86_VOYAGER
295 Machine Check Exception support allows the processor to notify the
296 kernel if it detects a problem (e.g. overheating, component failure).
297 The action the kernel takes depends on the severity of the problem,
298 ranging from a warning message on the console, to halting the machine.
299 Your processor must be a Pentium or newer to support this - check the
300 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
301 have a design flaw which leads to false MCE events - hence MCE is
302 disabled on all P5 processors, unless explicitly enabled with "mce"
303 as a boot argument. Similarly, if MCE is built in and creates a
304 problem on some new non-standard machine, you can boot with "nomce"
305 to disable it. MCE support simply ignores non-MCE processors like
306 the 386 and 486, so nearly everyone can say Y here.
308 config X86_MCE_NONFATAL
309 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
312 Enabling this feature starts a timer that triggers every 5 seconds which
313 will look at the machine check registers to see if anything happened.
314 Non-fatal problems automatically get corrected (but still logged).
315 Disable this if you don't want to see these messages.
316 Seeing the messages this option prints out may be indicative of dying hardware,
317 or out-of-spec (ie, overclocked) hardware.
318 This option only does something on certain CPUs.
319 (AMD Athlon/Duron and Intel Pentium 4)
321 config X86_MCE_P4THERMAL
322 bool "check for P4 thermal throttling interrupt."
323 depends on X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
325 Enabling this feature will cause a message to be printed when the P4
326 enters thermal throttling.
329 tristate "Toshiba Laptop support"
331 This adds a driver to safely access the System Management Mode of
332 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
333 not work on models with a Phoenix BIOS. The System Management Mode
334 is used to set the BIOS and power saving options on Toshiba portables.
336 For information on utilities to make use of this driver see the
337 Toshiba Linux utilities web site at:
338 <http://www.buzzard.org.uk/toshiba/>.
340 Say Y if you intend to run this kernel on a Toshiba portable.
344 tristate "Dell laptop support"
346 This adds a driver to safely access the System Management Mode
347 of the CPU on the Dell Inspiron 8000. The System Management Mode
348 is used to read cpu temperature and cooling fan status and to
349 control the fans on the I8K portables.
351 This driver has been tested only on the Inspiron 8000 but it may
352 also work with other Dell laptops. You can force loading on other
353 models by passing the parameter `force=1' to the module. Use at
356 For information on utilities to make use of this driver see the
357 I8K Linux utilities web site at:
358 <http://people.debian.org/~dz/i8k/>
360 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
363 config X86_REBOOTFIXUPS
364 bool "Enable X86 board specific fixups for reboot"
368 This enables chipset and/or board specific fixups to be done
369 in order to get reboot to work correctly. This is only needed on
370 some combinations of hardware and BIOS. The symptom, for which
371 this config is intended, is when reboot ends with a stalled/hung
374 Currently, the only fixup is for the Geode GX1/CS5530A/TROM2.1.
377 Say Y if you want to enable the fixup. Currently, it's safe to
378 enable this option even if you don't need it.
382 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
384 If you say Y here and also to "/dev file system support" in the
385 'File systems' section, you will be able to update the microcode on
386 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
387 Pentium III, Pentium 4, Xeon etc. You will obviously need the
388 actual microcode binary data itself which is not shipped with the
391 For latest news and information on obtaining all the required
392 ingredients for this driver, check:
393 <http://www.urbanmyth.org/microcode/>.
395 To compile this driver as a module, choose M here: the
396 module will be called microcode.
399 tristate "/dev/cpu/*/msr - Model-specific register support"
401 This device gives privileged processes access to the x86
402 Model-Specific Registers (MSRs). It is a character device with
403 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
404 MSR accesses are directed to a specific CPU on multi-processor
408 tristate "/dev/cpu/*/cpuid - CPU information support"
410 This device gives processes access to the x86 CPUID instruction to
411 be executed on a specific processor. It is a character device
412 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
415 source "drivers/firmware/Kconfig"
418 prompt "High Memory Support"
423 depends on !X86_NUMAQ
425 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
426 However, the address space of 32-bit x86 processors is only 4
427 Gigabytes large. That means that, if you have a large amount of
428 physical memory, not all of it can be "permanently mapped" by the
429 kernel. The physical memory that's not permanently mapped is called
432 If you are compiling a kernel which will never run on a machine with
433 more than 1 Gigabyte total physical RAM, answer "off" here (default
434 choice and suitable for most users). This will result in a "3GB/1GB"
435 split: 3GB are mapped so that each process sees a 3GB virtual memory
436 space and the remaining part of the 4GB virtual memory space is used
437 by the kernel to permanently map as much physical memory as
440 If the machine has between 1 and 4 Gigabytes physical RAM, then
443 If more than 4 Gigabytes is used then answer "64GB" here. This
444 selection turns Intel PAE (Physical Address Extension) mode on.
445 PAE implements 3-level paging on IA32 processors. PAE is fully
446 supported by Linux, PAE mode is implemented on all recent Intel
447 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
448 then the kernel will not boot on CPUs that don't support PAE!
450 The actual amount of total physical memory will either be
451 auto detected or can be forced by using a kernel command line option
452 such as "mem=256M". (Try "man bootparam" or see the documentation of
453 your boot loader (lilo or loadlin) about how to pass options to the
454 kernel at boot time.)
456 If unsure, say "off".
460 depends on !X86_NUMAQ
462 Select this if you have a 32-bit processor and between 1 and 4
463 gigabytes of physical RAM.
467 depends on X86_CMPXCHG64
469 Select this if you have a 32-bit processor and more than 4
470 gigabytes of physical RAM.
475 depends on EXPERIMENTAL && !X86_PAE
476 prompt "Memory split" if EMBEDDED
479 Select the desired split between kernel and user memory.
481 If the address range available to the kernel is less than the
482 physical memory installed, the remaining memory will be available
483 as "high memory". Accessing high memory is a little more costly
484 than low memory, as it needs to be mapped into the kernel first.
485 Note that increasing the kernel address space limits the range
486 available to user programs, making the address space there
487 tighter. Selecting anything other than the default 3G/1G split
488 will also likely make your kernel incompatible with binary-only
491 If you are not absolutely sure what you are doing, leave this
495 bool "3G/1G user/kernel split"
496 config VMSPLIT_3G_OPT
497 bool "3G/1G user/kernel split (for full 1G low memory)"
499 bool "2G/2G user/kernel split"
501 bool "1G/3G user/kernel split"
506 default 0xB0000000 if VMSPLIT_3G_OPT
507 default 0x78000000 if VMSPLIT_2G
508 default 0x40000000 if VMSPLIT_1G
513 depends on HIGHMEM64G || HIGHMEM4G
518 depends on HIGHMEM64G
521 # Common NUMA Features
523 bool "Numa Memory Allocation and Scheduler Support"
524 depends on SMP && HIGHMEM64G && (X86_NUMAQ || X86_GENERICARCH || (X86_SUMMIT && ACPI))
526 default y if (X86_NUMAQ || X86_SUMMIT)
528 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
529 depends on X86_SUMMIT && (!HIGHMEM64G || !ACPI)
533 default "4" if X86_NUMAQ
535 depends on NEED_MULTIPLE_NODES
537 config HAVE_ARCH_BOOTMEM_NODE
542 config ARCH_HAVE_MEMORY_PRESENT
544 depends on DISCONTIGMEM
547 config NEED_NODE_MEMMAP_SIZE
549 depends on DISCONTIGMEM || SPARSEMEM
552 config HAVE_ARCH_ALLOC_REMAP
557 config ARCH_FLATMEM_ENABLE
559 depends on (ARCH_SELECT_MEMORY_MODEL && X86_PC)
561 config ARCH_DISCONTIGMEM_ENABLE
565 config ARCH_DISCONTIGMEM_DEFAULT
569 config ARCH_SPARSEMEM_ENABLE
571 depends on (NUMA || (X86_PC && EXPERIMENTAL))
572 select SPARSEMEM_STATIC
574 config ARCH_SELECT_MEMORY_MODEL
576 depends on ARCH_SPARSEMEM_ENABLE
580 config HAVE_ARCH_EARLY_PFN_TO_NID
586 bool "Allocate 3rd-level pagetables from highmem"
587 depends on HIGHMEM4G || HIGHMEM64G
589 The VM uses one page table entry for each page of physical memory.
590 For systems with a lot of RAM, this can be wasteful of precious
591 low memory. Setting this option will put user-space page table
592 entries in high memory.
594 config MATH_EMULATION
595 bool "Math emulation"
597 Linux can emulate a math coprocessor (used for floating point
598 operations) if you don't have one. 486DX and Pentium processors have
599 a math coprocessor built in, 486SX and 386 do not, unless you added
600 a 487DX or 387, respectively. (The messages during boot time can
601 give you some hints here ["man dmesg"].) Everyone needs either a
602 coprocessor or this emulation.
604 If you don't have a math coprocessor, you need to say Y here; if you
605 say Y here even though you have a coprocessor, the coprocessor will
606 be used nevertheless. (This behavior can be changed with the kernel
607 command line option "no387", which comes handy if your coprocessor
608 is broken. Try "man bootparam" or see the documentation of your boot
609 loader (lilo or loadlin) about how to pass options to the kernel at
610 boot time.) This means that it is a good idea to say Y here if you
611 intend to use this kernel on different machines.
613 More information about the internals of the Linux math coprocessor
614 emulation can be found in <file:arch/i386/math-emu/README>.
616 If you are not sure, say Y; apart from resulting in a 66 KB bigger
617 kernel, it won't hurt.
620 bool "MTRR (Memory Type Range Register) support"
622 On Intel P6 family processors (Pentium Pro, Pentium II and later)
623 the Memory Type Range Registers (MTRRs) may be used to control
624 processor access to memory ranges. This is most useful if you have
625 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
626 allows bus write transfers to be combined into a larger transfer
627 before bursting over the PCI/AGP bus. This can increase performance
628 of image write operations 2.5 times or more. Saying Y here creates a
629 /proc/mtrr file which may be used to manipulate your processor's
630 MTRRs. Typically the X server should use this.
632 This code has a reasonably generic interface so that similar
633 control registers on other processors can be easily supported
636 The Cyrix 6x86, 6x86MX and M II processors have Address Range
637 Registers (ARRs) which provide a similar functionality to MTRRs. For
638 these, the ARRs are used to emulate the MTRRs.
639 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
640 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
641 write-combining. All of these processors are supported by this code
642 and it makes sense to say Y here if you have one of them.
644 Saying Y here also fixes a problem with buggy SMP BIOSes which only
645 set the MTRRs for the boot CPU and not for the secondary CPUs. This
646 can lead to all sorts of problems, so it's good to say Y here.
648 You can safely say Y even if your machine doesn't have MTRRs, you'll
649 just add about 9 KB to your kernel.
651 See <file:Documentation/mtrr.txt> for more information.
654 bool "Boot from EFI support (EXPERIMENTAL)"
658 This enables the the kernel to boot on EFI platforms using
659 system configuration information passed to it from the firmware.
660 This also enables the kernel to use any EFI runtime services that are
661 available (such as the EFI variable services).
663 This option is only useful on systems that have EFI firmware
664 and will result in a kernel image that is ~8k larger. In addition,
665 you must use the latest ELILO loader available at
666 <http://elilo.sourceforge.net> in order to take advantage of
667 kernel initialization using EFI information (neither GRUB nor LILO know
668 anything about EFI). However, even with this option, the resultant
669 kernel should continue to boot on existing non-EFI platforms.
672 bool "Enable kernel irq balancing"
673 depends on SMP && X86_IO_APIC
676 The default yes will allow the kernel to do irq load balancing.
677 Saying no will keep the kernel from doing irq load balancing.
679 # turning this on wastes a bunch of space.
680 # Summit needs it only when NUMA is on
683 depends on (((X86_SUMMIT || X86_GENERICARCH) && NUMA) || (X86 && EFI))
687 bool "Use register arguments"
690 Compile the kernel with -mregparm=3. This instructs gcc to use
691 a more efficient function call ABI which passes the first three
692 arguments of a function call via registers, which results in denser
695 If this option is disabled, then the default ABI of passing
696 arguments via the stack is used.
701 bool "Enable seccomp to safely compute untrusted bytecode"
705 This kernel feature is useful for number crunching applications
706 that may need to compute untrusted bytecode during their
707 execution. By using pipes or other transports made available to
708 the process as file descriptors supporting the read/write
709 syscalls, it's possible to isolate those applications in
710 their own address space using seccomp. Once seccomp is
711 enabled via /proc/<pid>/seccomp, it cannot be disabled
712 and the task is only allowed to execute a few safe syscalls
713 defined by each seccomp mode.
715 If unsure, say Y. Only embedded should say N here.
717 source kernel/Kconfig.hz
720 bool "kexec system call (EXPERIMENTAL)"
721 depends on EXPERIMENTAL
723 kexec is a system call that implements the ability to shutdown your
724 current kernel, and to start another kernel. It is like a reboot
725 but it is indepedent of the system firmware. And like a reboot
726 you can start any kernel with it, not just Linux.
728 The name comes from the similiarity to the exec system call.
730 It is an ongoing process to be certain the hardware in a machine
731 is properly shutdown, so do not be surprised if this code does not
732 initially work for you. It may help to enable device hotplugging
733 support. As of this writing the exact hardware interface is
734 strongly in flux, so no good recommendation can be made.
737 bool "kernel crash dumps (EXPERIMENTAL)"
738 depends on EXPERIMENTAL
741 Generate crash dump after being started by kexec.
743 config PHYSICAL_START
744 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
746 default "0x1000000" if CRASH_DUMP
749 This gives the physical address where the kernel is loaded. Normally
750 for regular kernels this value is 0x100000 (1MB). But in the case
751 of kexec on panic the fail safe kernel needs to run at a different
752 address than the panic-ed kernel. This option is used to set the load
753 address for kernels used to capture crash dump on being kexec'ed
754 after panic. The default value for crash dump kernels is
755 0x1000000 (16MB). This can also be set based on the "X" value as
756 specified in the "crashkernel=YM@XM" command line boot parameter
757 passed to the panic-ed kernel. Typically this parameter is set as
758 crashkernel=64M@16M. Please take a look at
759 Documentation/kdump/kdump.txt for more details about crash dumps.
761 Don't change this unless you know what you are doing.
764 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
765 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
767 Say Y here to experiment with turning CPUs off and on, and to
768 enable suspend on SMP systems. CPUs can be controlled through
769 /sys/devices/system/cpu.
775 menu "Power management options (ACPI, APM)"
776 depends on !X86_VOYAGER
778 source kernel/power/Kconfig
780 source "drivers/acpi/Kconfig"
782 menu "APM (Advanced Power Management) BIOS Support"
783 depends on PM && !X86_VISWS
786 tristate "APM (Advanced Power Management) BIOS support"
789 APM is a BIOS specification for saving power using several different
790 techniques. This is mostly useful for battery powered laptops with
791 APM compliant BIOSes. If you say Y here, the system time will be
792 reset after a RESUME operation, the /proc/apm device will provide
793 battery status information, and user-space programs will receive
794 notification of APM "events" (e.g. battery status change).
796 If you select "Y" here, you can disable actual use of the APM
797 BIOS by passing the "apm=off" option to the kernel at boot time.
799 Note that the APM support is almost completely disabled for
800 machines with more than one CPU.
802 In order to use APM, you will need supporting software. For location
803 and more information, read <file:Documentation/pm.txt> and the
804 Battery Powered Linux mini-HOWTO, available from
805 <http://www.tldp.org/docs.html#howto>.
807 This driver does not spin down disk drives (see the hdparm(8)
808 manpage ("man 8 hdparm") for that), and it doesn't turn off
809 VESA-compliant "green" monitors.
811 This driver does not support the TI 4000M TravelMate and the ACER
812 486/DX4/75 because they don't have compliant BIOSes. Many "green"
813 desktop machines also don't have compliant BIOSes, and this driver
814 may cause those machines to panic during the boot phase.
816 Generally, if you don't have a battery in your machine, there isn't
817 much point in using this driver and you should say N. If you get
818 random kernel OOPSes or reboots that don't seem to be related to
819 anything, try disabling/enabling this option (or disabling/enabling
822 Some other things you should try when experiencing seemingly random,
825 1) make sure that you have enough swap space and that it is
827 2) pass the "no-hlt" option to the kernel
828 3) switch on floating point emulation in the kernel and pass
829 the "no387" option to the kernel
830 4) pass the "floppy=nodma" option to the kernel
831 5) pass the "mem=4M" option to the kernel (thereby disabling
832 all but the first 4 MB of RAM)
833 6) make sure that the CPU is not over clocked.
834 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
835 8) disable the cache from your BIOS settings
836 9) install a fan for the video card or exchange video RAM
837 10) install a better fan for the CPU
838 11) exchange RAM chips
839 12) exchange the motherboard.
841 To compile this driver as a module, choose M here: the
842 module will be called apm.
844 config APM_IGNORE_USER_SUSPEND
845 bool "Ignore USER SUSPEND"
848 This option will ignore USER SUSPEND requests. On machines with a
849 compliant APM BIOS, you want to say N. However, on the NEC Versa M
850 series notebooks, it is necessary to say Y because of a BIOS bug.
853 bool "Enable PM at boot time"
856 Enable APM features at boot time. From page 36 of the APM BIOS
857 specification: "When disabled, the APM BIOS does not automatically
858 power manage devices, enter the Standby State, enter the Suspend
859 State, or take power saving steps in response to CPU Idle calls."
860 This driver will make CPU Idle calls when Linux is idle (unless this
861 feature is turned off -- see "Do CPU IDLE calls", below). This
862 should always save battery power, but more complicated APM features
863 will be dependent on your BIOS implementation. You may need to turn
864 this option off if your computer hangs at boot time when using APM
865 support, or if it beeps continuously instead of suspending. Turn
866 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
867 T400CDT. This is off by default since most machines do fine without
871 bool "Make CPU Idle calls when idle"
874 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
875 On some machines, this can activate improved power savings, such as
876 a slowed CPU clock rate, when the machine is idle. These idle calls
877 are made after the idle loop has run for some length of time (e.g.,
878 333 mS). On some machines, this will cause a hang at boot time or
879 whenever the CPU becomes idle. (On machines with more than one CPU,
880 this option does nothing.)
882 config APM_DISPLAY_BLANK
883 bool "Enable console blanking using APM"
886 Enable console blanking using the APM. Some laptops can use this to
887 turn off the LCD backlight when the screen blanker of the Linux
888 virtual console blanks the screen. Note that this is only used by
889 the virtual console screen blanker, and won't turn off the backlight
890 when using the X Window system. This also doesn't have anything to
891 do with your VESA-compliant power-saving monitor. Further, this
892 option doesn't work for all laptops -- it might not turn off your
893 backlight at all, or it might print a lot of errors to the console,
894 especially if you are using gpm.
896 config APM_RTC_IS_GMT
897 bool "RTC stores time in GMT"
900 Say Y here if your RTC (Real Time Clock a.k.a. hardware clock)
901 stores the time in GMT (Greenwich Mean Time). Say N if your RTC
904 It is in fact recommended to store GMT in your RTC, because then you
905 don't have to worry about daylight savings time changes. The only
906 reason not to use GMT in your RTC is if you also run a broken OS
907 that doesn't understand GMT.
909 config APM_ALLOW_INTS
910 bool "Allow interrupts during APM BIOS calls"
913 Normally we disable external interrupts while we are making calls to
914 the APM BIOS as a measure to lessen the effects of a badly behaving
915 BIOS implementation. The BIOS should reenable interrupts if it
916 needs to. Unfortunately, some BIOSes do not -- especially those in
917 many of the newer IBM Thinkpads. If you experience hangs when you
918 suspend, try setting this to Y. Otherwise, say N.
920 config APM_REAL_MODE_POWER_OFF
921 bool "Use real mode APM BIOS call to power off"
924 Use real mode APM BIOS calls to switch off the computer. This is
925 a work-around for a number of buggy BIOSes. Switch this option on if
926 your computer crashes instead of powering off properly.
930 source "arch/i386/kernel/cpu/cpufreq/Kconfig"
934 menu "Bus options (PCI, PCMCIA, EISA, MCA, ISA)"
937 bool "PCI support" if !X86_VISWS
938 depends on !X86_VOYAGER
939 default y if X86_VISWS
941 Find out whether you have a PCI motherboard. PCI is the name of a
942 bus system, i.e. the way the CPU talks to the other stuff inside
943 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
944 VESA. If you have PCI, say Y, otherwise N.
946 The PCI-HOWTO, available from
947 <http://www.tldp.org/docs.html#howto>, contains valuable
948 information about which PCI hardware does work under Linux and which
952 prompt "PCI access mode"
953 depends on PCI && !X86_VISWS
956 On PCI systems, the BIOS can be used to detect the PCI devices and
957 determine their configuration. However, some old PCI motherboards
958 have BIOS bugs and may crash if this is done. Also, some embedded
959 PCI-based systems don't have any BIOS at all. Linux can also try to
960 detect the PCI hardware directly without using the BIOS.
962 With this option, you can specify how Linux should detect the
963 PCI devices. If you choose "BIOS", the BIOS will be used,
964 if you choose "Direct", the BIOS won't be used, and if you
965 choose "MMConfig", then PCI Express MMCONFIG will be used.
966 If you choose "Any", the kernel will try MMCONFIG, then the
967 direct access method and falls back to the BIOS if that doesn't
968 work. If unsure, go with the default, which is "Any".
973 config PCI_GOMMCONFIG
986 depends on !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
991 depends on PCI && ((PCI_GODIRECT || PCI_GOANY) || X86_VISWS)
996 depends on PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
999 source "drivers/pci/pcie/Kconfig"
1001 source "drivers/pci/Kconfig"
1009 depends on !(X86_VOYAGER || X86_VISWS)
1011 Find out whether you have ISA slots on your motherboard. ISA is the
1012 name of a bus system, i.e. the way the CPU talks to the other stuff
1013 inside your box. Other bus systems are PCI, EISA, MicroChannel
1014 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1015 newer boards don't support it. If you have ISA, say Y, otherwise N.
1021 The Extended Industry Standard Architecture (EISA) bus was
1022 developed as an open alternative to the IBM MicroChannel bus.
1024 The EISA bus provided some of the features of the IBM MicroChannel
1025 bus while maintaining backward compatibility with cards made for
1026 the older ISA bus. The EISA bus saw limited use between 1988 and
1027 1995 when it was made obsolete by the PCI bus.
1029 Say Y here if you are building a kernel for an EISA-based machine.
1033 source "drivers/eisa/Kconfig"
1036 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1037 default y if X86_VOYAGER
1039 MicroChannel Architecture is found in some IBM PS/2 machines and
1040 laptops. It is a bus system similar to PCI or ISA. See
1041 <file:Documentation/mca.txt> (and especially the web page given
1042 there) before attempting to build an MCA bus kernel.
1044 source "drivers/mca/Kconfig"
1047 tristate "NatSemi SCx200 support"
1048 depends on !X86_VOYAGER
1050 This provides basic support for the National Semiconductor SCx200
1051 processor. Right now this is just a driver for the GPIO pins.
1053 If you don't know what to do here, say N.
1055 This support is also available as a module. If compiled as a
1056 module, it will be called scx200.
1058 source "drivers/pcmcia/Kconfig"
1060 source "drivers/pci/hotplug/Kconfig"
1064 menu "Executable file formats"
1066 source "fs/Kconfig.binfmt"
1070 source "net/Kconfig"
1072 source "drivers/Kconfig"
1076 menu "Instrumentation Support"
1077 depends on EXPERIMENTAL
1079 source "arch/i386/oprofile/Kconfig"
1082 bool "Kprobes (EXPERIMENTAL)"
1083 depends on EXPERIMENTAL && MODULES
1085 Kprobes allows you to trap at almost any kernel address and
1086 execute a callback function. register_kprobe() establishes
1087 a probepoint and specifies the callback. Kprobes is useful
1088 for kernel debugging, non-intrusive instrumentation and testing.
1089 If in doubt, say "N".
1092 source "arch/i386/Kconfig.debug"
1094 source "security/Kconfig"
1096 source "crypto/Kconfig"
1098 source "lib/Kconfig"
1101 # Use the generic interrupt handling code in kernel/irq/:
1103 config GENERIC_HARDIRQS
1107 config GENERIC_IRQ_PROBE
1111 config GENERIC_PENDING_IRQ
1113 depends on GENERIC_HARDIRQS && SMP
1118 depends on SMP && !X86_VOYAGER
1123 depends on SMP && !(X86_VISWS || X86_VOYAGER)
1126 config X86_BIOS_REBOOT
1128 depends on !(X86_VISWS || X86_VOYAGER)
1131 config X86_TRAMPOLINE
1133 depends on X86_SMP || (X86_VOYAGER && SMP)