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.
21 config LOCKDEP_SUPPORT
25 config STACKTRACE_SUPPORT
29 config SEMAPHORE_SLEEPERS
44 config GENERIC_ISA_DMA
52 config GENERIC_HWEIGHT
56 config ARCH_MAY_HAVE_PC_FDC
66 menu "Processor type and features"
69 bool "Symmetric multi-processing support"
71 This enables support for systems with more than one CPU. If you have
72 a system with only one CPU, like most personal computers, say N. If
73 you have a system with more than one CPU, say Y.
75 If you say N here, the kernel will run on single and multiprocessor
76 machines, but will use only one CPU of a multiprocessor machine. If
77 you say Y here, the kernel will run on many, but not all,
78 singleprocessor machines. On a singleprocessor machine, the kernel
79 will run faster if you say N here.
81 Note that if you say Y here and choose architecture "586" or
82 "Pentium" under "Processor family", the kernel will not work on 486
83 architectures. Similarly, multiprocessor kernels for the "PPro"
84 architecture may not work on all Pentium based boards.
86 People using multiprocessor machines who say Y here should also say
87 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
88 Management" code will be disabled if you say Y here.
90 See also the <file:Documentation/smp.txt>,
91 <file:Documentation/i386/IO-APIC.txt>,
92 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
93 <http://www.tldp.org/docs.html#howto>.
95 If you don't know what to do here, say N.
98 prompt "Subarchitecture Type"
104 Choose this option if your computer is a standard PC or compatible.
109 Select this for an AMD Elan processor.
111 Do not use this option for K6/Athlon/Opteron processors!
113 If unsure, choose "PC-compatible" instead.
118 Voyager is an MCA-based 32-way capable SMP architecture proprietary
119 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
123 If you do not specifically know you have a Voyager based machine,
124 say N here, otherwise the kernel you build will not be bootable.
127 bool "NUMAQ (IBM/Sequent)"
131 This option is used for getting Linux to run on a (IBM/Sequent) NUMA
132 multiquad box. This changes the way that processors are bootstrapped,
133 and uses Clustered Logical APIC addressing mode instead of Flat Logical.
134 You will need a new lynxer.elf file to flash your firmware with - send
135 email to <Martin.Bligh@us.ibm.com>.
138 bool "Summit/EXA (IBM x440)"
141 This option is needed for IBM systems that use the Summit/EXA chipset.
142 In particular, it is needed for the x440.
144 If you don't have one of these computers, you should say N here.
147 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
150 This option is needed for the systems that have more than 8 CPUs
151 and if the system is not of any sub-arch type above.
153 If you don't have such a system, you should say N here.
156 bool "SGI 320/540 (Visual Workstation)"
158 The SGI Visual Workstation series is an IA32-based workstation
159 based on SGI systems chips with some legacy PC hardware attached.
161 Say Y here to create a kernel to run on the SGI 320 or 540.
163 A kernel compiled for the Visual Workstation will not run on PCs
164 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
166 config X86_GENERICARCH
167 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
170 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
171 It is intended for a generic binary kernel.
174 bool "Support for Unisys ES7000 IA32 series"
177 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
178 supposed to run on an IA32-based Unisys ES7000 system.
179 Only choose this option if you have such a system, otherwise you
187 depends on ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
190 config HAVE_ARCH_PARSE_SRAT
195 config X86_SUMMIT_NUMA
198 depends on NUMA && (X86_SUMMIT || X86_GENERICARCH)
200 config X86_CYCLONE_TIMER
203 depends on X86_SUMMIT || X86_GENERICARCH
205 config ES7000_CLUSTERED_APIC
208 depends on SMP && X86_ES7000 && MPENTIUMIII
210 source "arch/i386/Kconfig.cpu"
213 bool "HPET Timer Support"
215 This enables the use of the HPET for the kernel's internal timer.
216 HPET is the next generation timer replacing legacy 8254s.
217 You can safely choose Y here. However, HPET will only be
218 activated if the platform and the BIOS support this feature.
219 Otherwise the 8254 will be used for timing services.
221 Choose N to continue using the legacy 8254 timer.
223 config HPET_EMULATE_RTC
225 depends on HPET_TIMER && RTC=y
229 int "Maximum number of CPUs (2-255)"
232 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
235 This allows you to specify the maximum number of CPUs which this
236 kernel will support. The maximum supported value is 255 and the
237 minimum value which makes sense is 2.
239 This is purely to save memory - each supported CPU adds
240 approximately eight kilobytes to the kernel image.
243 bool "SMT (Hyperthreading) scheduler support"
246 SMT scheduler support improves the CPU scheduler's decision making
247 when dealing with Intel Pentium 4 chips with HyperThreading at a
248 cost of slightly increased overhead in some places. If unsure say
252 bool "Multi-core scheduler support"
256 Multi-core scheduler support improves the CPU scheduler's decision
257 making when dealing with multi-core CPU chips at a cost of slightly
258 increased overhead in some places. If unsure say N here.
260 source "kernel/Kconfig.preempt"
263 bool "Local APIC support on uniprocessors"
264 depends on !SMP && !(X86_VISWS || X86_VOYAGER)
266 A local APIC (Advanced Programmable Interrupt Controller) is an
267 integrated interrupt controller in the CPU. If you have a single-CPU
268 system which has a processor with a local APIC, you can say Y here to
269 enable and use it. If you say Y here even though your machine doesn't
270 have a local APIC, then the kernel will still run with no slowdown at
271 all. The local APIC supports CPU-generated self-interrupts (timer,
272 performance counters), and the NMI watchdog which detects hard
276 bool "IO-APIC support on uniprocessors"
277 depends on X86_UP_APIC
279 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
280 SMP-capable replacement for PC-style interrupt controllers. Most
281 SMP systems and many recent uniprocessor systems have one.
283 If you have a single-CPU system with an IO-APIC, you can say Y here
284 to use it. If you say Y here even though your machine doesn't have
285 an IO-APIC, then the kernel will still run with no slowdown at all.
287 config X86_LOCAL_APIC
289 depends on X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER)
294 depends on X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER))
297 config X86_VISWS_APIC
303 bool "Machine Check Exception"
304 depends on !X86_VOYAGER
306 Machine Check Exception support allows the processor to notify the
307 kernel if it detects a problem (e.g. overheating, component failure).
308 The action the kernel takes depends on the severity of the problem,
309 ranging from a warning message on the console, to halting the machine.
310 Your processor must be a Pentium or newer to support this - check the
311 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
312 have a design flaw which leads to false MCE events - hence MCE is
313 disabled on all P5 processors, unless explicitly enabled with "mce"
314 as a boot argument. Similarly, if MCE is built in and creates a
315 problem on some new non-standard machine, you can boot with "nomce"
316 to disable it. MCE support simply ignores non-MCE processors like
317 the 386 and 486, so nearly everyone can say Y here.
319 config X86_MCE_NONFATAL
320 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
323 Enabling this feature starts a timer that triggers every 5 seconds which
324 will look at the machine check registers to see if anything happened.
325 Non-fatal problems automatically get corrected (but still logged).
326 Disable this if you don't want to see these messages.
327 Seeing the messages this option prints out may be indicative of dying hardware,
328 or out-of-spec (ie, overclocked) hardware.
329 This option only does something on certain CPUs.
330 (AMD Athlon/Duron and Intel Pentium 4)
332 config X86_MCE_P4THERMAL
333 bool "check for P4 thermal throttling interrupt."
334 depends on X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
336 Enabling this feature will cause a message to be printed when the P4
337 enters thermal throttling.
341 bool "Enable VM86 support" if EMBEDDED
343 This option is required by programs like DOSEMU to run 16-bit legacy
344 code on X86 processors. It also may be needed by software like
345 XFree86 to initialize some video cards via BIOS. Disabling this
346 option saves about 6k.
349 tristate "Toshiba Laptop support"
351 This adds a driver to safely access the System Management Mode of
352 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
353 not work on models with a Phoenix BIOS. The System Management Mode
354 is used to set the BIOS and power saving options on Toshiba portables.
356 For information on utilities to make use of this driver see the
357 Toshiba Linux utilities web site at:
358 <http://www.buzzard.org.uk/toshiba/>.
360 Say Y if you intend to run this kernel on a Toshiba portable.
364 tristate "Dell laptop support"
366 This adds a driver to safely access the System Management Mode
367 of the CPU on the Dell Inspiron 8000. The System Management Mode
368 is used to read cpu temperature and cooling fan status and to
369 control the fans on the I8K portables.
371 This driver has been tested only on the Inspiron 8000 but it may
372 also work with other Dell laptops. You can force loading on other
373 models by passing the parameter `force=1' to the module. Use at
376 For information on utilities to make use of this driver see the
377 I8K Linux utilities web site at:
378 <http://people.debian.org/~dz/i8k/>
380 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
383 config X86_REBOOTFIXUPS
384 bool "Enable X86 board specific fixups for reboot"
388 This enables chipset and/or board specific fixups to be done
389 in order to get reboot to work correctly. This is only needed on
390 some combinations of hardware and BIOS. The symptom, for which
391 this config is intended, is when reboot ends with a stalled/hung
394 Currently, the only fixup is for the Geode GX1/CS5530A/TROM2.1.
397 Say Y if you want to enable the fixup. Currently, it's safe to
398 enable this option even if you don't need it.
402 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
404 If you say Y here and also to "/dev file system support" in the
405 'File systems' section, you will be able to update the microcode on
406 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
407 Pentium III, Pentium 4, Xeon etc. You will obviously need the
408 actual microcode binary data itself which is not shipped with the
411 For latest news and information on obtaining all the required
412 ingredients for this driver, check:
413 <http://www.urbanmyth.org/microcode/>.
415 To compile this driver as a module, choose M here: the
416 module will be called microcode.
419 tristate "/dev/cpu/*/msr - Model-specific register support"
421 This device gives privileged processes access to the x86
422 Model-Specific Registers (MSRs). It is a character device with
423 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
424 MSR accesses are directed to a specific CPU on multi-processor
428 tristate "/dev/cpu/*/cpuid - CPU information support"
430 This device gives processes access to the x86 CPUID instruction to
431 be executed on a specific processor. It is a character device
432 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
435 source "drivers/firmware/Kconfig"
438 prompt "High Memory Support"
443 depends on !X86_NUMAQ
445 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
446 However, the address space of 32-bit x86 processors is only 4
447 Gigabytes large. That means that, if you have a large amount of
448 physical memory, not all of it can be "permanently mapped" by the
449 kernel. The physical memory that's not permanently mapped is called
452 If you are compiling a kernel which will never run on a machine with
453 more than 1 Gigabyte total physical RAM, answer "off" here (default
454 choice and suitable for most users). This will result in a "3GB/1GB"
455 split: 3GB are mapped so that each process sees a 3GB virtual memory
456 space and the remaining part of the 4GB virtual memory space is used
457 by the kernel to permanently map as much physical memory as
460 If the machine has between 1 and 4 Gigabytes physical RAM, then
463 If more than 4 Gigabytes is used then answer "64GB" here. This
464 selection turns Intel PAE (Physical Address Extension) mode on.
465 PAE implements 3-level paging on IA32 processors. PAE is fully
466 supported by Linux, PAE mode is implemented on all recent Intel
467 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
468 then the kernel will not boot on CPUs that don't support PAE!
470 The actual amount of total physical memory will either be
471 auto detected or can be forced by using a kernel command line option
472 such as "mem=256M". (Try "man bootparam" or see the documentation of
473 your boot loader (lilo or loadlin) about how to pass options to the
474 kernel at boot time.)
476 If unsure, say "off".
480 depends on !X86_NUMAQ
482 Select this if you have a 32-bit processor and between 1 and 4
483 gigabytes of physical RAM.
487 depends on X86_CMPXCHG64
489 Select this if you have a 32-bit processor and more than 4
490 gigabytes of physical RAM.
495 depends on EXPERIMENTAL && !X86_PAE
496 prompt "Memory split" if EMBEDDED
499 Select the desired split between kernel and user memory.
501 If the address range available to the kernel is less than the
502 physical memory installed, the remaining memory will be available
503 as "high memory". Accessing high memory is a little more costly
504 than low memory, as it needs to be mapped into the kernel first.
505 Note that increasing the kernel address space limits the range
506 available to user programs, making the address space there
507 tighter. Selecting anything other than the default 3G/1G split
508 will also likely make your kernel incompatible with binary-only
511 If you are not absolutely sure what you are doing, leave this
515 bool "3G/1G user/kernel split"
516 config VMSPLIT_3G_OPT
517 bool "3G/1G user/kernel split (for full 1G low memory)"
519 bool "2G/2G user/kernel split"
521 bool "1G/3G user/kernel split"
526 default 0xB0000000 if VMSPLIT_3G_OPT
527 default 0x78000000 if VMSPLIT_2G
528 default 0x40000000 if VMSPLIT_1G
533 depends on HIGHMEM64G || HIGHMEM4G
538 depends on HIGHMEM64G
540 select RESOURCES_64BIT
542 # Common NUMA Features
544 bool "Numa Memory Allocation and Scheduler Support"
545 depends on SMP && HIGHMEM64G && (X86_NUMAQ || X86_GENERICARCH || (X86_SUMMIT && ACPI))
547 default y if (X86_NUMAQ || X86_SUMMIT)
549 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
550 depends on X86_SUMMIT && (!HIGHMEM64G || !ACPI)
554 default "4" if X86_NUMAQ
556 depends on NEED_MULTIPLE_NODES
558 config HAVE_ARCH_BOOTMEM_NODE
563 config ARCH_HAVE_MEMORY_PRESENT
565 depends on DISCONTIGMEM
568 config NEED_NODE_MEMMAP_SIZE
570 depends on DISCONTIGMEM || SPARSEMEM
573 config HAVE_ARCH_ALLOC_REMAP
578 config ARCH_FLATMEM_ENABLE
580 depends on (ARCH_SELECT_MEMORY_MODEL && X86_PC)
582 config ARCH_DISCONTIGMEM_ENABLE
586 config ARCH_DISCONTIGMEM_DEFAULT
590 config ARCH_SPARSEMEM_ENABLE
592 depends on (NUMA || (X86_PC && EXPERIMENTAL))
593 select SPARSEMEM_STATIC
595 config ARCH_SELECT_MEMORY_MODEL
597 depends on ARCH_SPARSEMEM_ENABLE
601 config HAVE_ARCH_EARLY_PFN_TO_NID
607 bool "Allocate 3rd-level pagetables from highmem"
608 depends on HIGHMEM4G || HIGHMEM64G
610 The VM uses one page table entry for each page of physical memory.
611 For systems with a lot of RAM, this can be wasteful of precious
612 low memory. Setting this option will put user-space page table
613 entries in high memory.
615 config MATH_EMULATION
616 bool "Math emulation"
618 Linux can emulate a math coprocessor (used for floating point
619 operations) if you don't have one. 486DX and Pentium processors have
620 a math coprocessor built in, 486SX and 386 do not, unless you added
621 a 487DX or 387, respectively. (The messages during boot time can
622 give you some hints here ["man dmesg"].) Everyone needs either a
623 coprocessor or this emulation.
625 If you don't have a math coprocessor, you need to say Y here; if you
626 say Y here even though you have a coprocessor, the coprocessor will
627 be used nevertheless. (This behavior can be changed with the kernel
628 command line option "no387", which comes handy if your coprocessor
629 is broken. Try "man bootparam" or see the documentation of your boot
630 loader (lilo or loadlin) about how to pass options to the kernel at
631 boot time.) This means that it is a good idea to say Y here if you
632 intend to use this kernel on different machines.
634 More information about the internals of the Linux math coprocessor
635 emulation can be found in <file:arch/i386/math-emu/README>.
637 If you are not sure, say Y; apart from resulting in a 66 KB bigger
638 kernel, it won't hurt.
641 bool "MTRR (Memory Type Range Register) support"
643 On Intel P6 family processors (Pentium Pro, Pentium II and later)
644 the Memory Type Range Registers (MTRRs) may be used to control
645 processor access to memory ranges. This is most useful if you have
646 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
647 allows bus write transfers to be combined into a larger transfer
648 before bursting over the PCI/AGP bus. This can increase performance
649 of image write operations 2.5 times or more. Saying Y here creates a
650 /proc/mtrr file which may be used to manipulate your processor's
651 MTRRs. Typically the X server should use this.
653 This code has a reasonably generic interface so that similar
654 control registers on other processors can be easily supported
657 The Cyrix 6x86, 6x86MX and M II processors have Address Range
658 Registers (ARRs) which provide a similar functionality to MTRRs. For
659 these, the ARRs are used to emulate the MTRRs.
660 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
661 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
662 write-combining. All of these processors are supported by this code
663 and it makes sense to say Y here if you have one of them.
665 Saying Y here also fixes a problem with buggy SMP BIOSes which only
666 set the MTRRs for the boot CPU and not for the secondary CPUs. This
667 can lead to all sorts of problems, so it's good to say Y here.
669 You can safely say Y even if your machine doesn't have MTRRs, you'll
670 just add about 9 KB to your kernel.
672 See <file:Documentation/mtrr.txt> for more information.
675 bool "Boot from EFI support (EXPERIMENTAL)"
679 This enables the the kernel to boot on EFI platforms using
680 system configuration information passed to it from the firmware.
681 This also enables the kernel to use any EFI runtime services that are
682 available (such as the EFI variable services).
684 This option is only useful on systems that have EFI firmware
685 and will result in a kernel image that is ~8k larger. In addition,
686 you must use the latest ELILO loader available at
687 <http://elilo.sourceforge.net> in order to take advantage of
688 kernel initialization using EFI information (neither GRUB nor LILO know
689 anything about EFI). However, even with this option, the resultant
690 kernel should continue to boot on existing non-EFI platforms.
693 bool "Enable kernel irq balancing"
694 depends on SMP && X86_IO_APIC
697 The default yes will allow the kernel to do irq load balancing.
698 Saying no will keep the kernel from doing irq load balancing.
700 # turning this on wastes a bunch of space.
701 # Summit needs it only when NUMA is on
704 depends on (((X86_SUMMIT || X86_GENERICARCH) && NUMA) || (X86 && EFI))
708 bool "Use register arguments"
711 Compile the kernel with -mregparm=3. This instructs gcc to use
712 a more efficient function call ABI which passes the first three
713 arguments of a function call via registers, which results in denser
716 If this option is disabled, then the default ABI of passing
717 arguments via the stack is used.
722 bool "Enable seccomp to safely compute untrusted bytecode"
726 This kernel feature is useful for number crunching applications
727 that may need to compute untrusted bytecode during their
728 execution. By using pipes or other transports made available to
729 the process as file descriptors supporting the read/write
730 syscalls, it's possible to isolate those applications in
731 their own address space using seccomp. Once seccomp is
732 enabled via /proc/<pid>/seccomp, it cannot be disabled
733 and the task is only allowed to execute a few safe syscalls
734 defined by each seccomp mode.
736 If unsure, say Y. Only embedded should say N here.
738 source kernel/Kconfig.hz
741 bool "kexec system call (EXPERIMENTAL)"
742 depends on EXPERIMENTAL
744 kexec is a system call that implements the ability to shutdown your
745 current kernel, and to start another kernel. It is like a reboot
746 but it is independent of the system firmware. And like a reboot
747 you can start any kernel with it, not just Linux.
749 The name comes from the similarity to the exec system call.
751 It is an ongoing process to be certain the hardware in a machine
752 is properly shutdown, so do not be surprised if this code does not
753 initially work for you. It may help to enable device hotplugging
754 support. As of this writing the exact hardware interface is
755 strongly in flux, so no good recommendation can be made.
758 bool "kernel crash dumps (EXPERIMENTAL)"
759 depends on EXPERIMENTAL
762 Generate crash dump after being started by kexec.
764 config PHYSICAL_START
765 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
767 default "0x1000000" if CRASH_DUMP
770 This gives the physical address where the kernel is loaded. Normally
771 for regular kernels this value is 0x100000 (1MB). But in the case
772 of kexec on panic the fail safe kernel needs to run at a different
773 address than the panic-ed kernel. This option is used to set the load
774 address for kernels used to capture crash dump on being kexec'ed
775 after panic. The default value for crash dump kernels is
776 0x1000000 (16MB). This can also be set based on the "X" value as
777 specified in the "crashkernel=YM@XM" command line boot parameter
778 passed to the panic-ed kernel. Typically this parameter is set as
779 crashkernel=64M@16M. Please take a look at
780 Documentation/kdump/kdump.txt for more details about crash dumps.
782 Don't change this unless you know what you are doing.
785 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
786 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
788 Say Y here to experiment with turning CPUs off and on, and to
789 enable suspend on SMP systems. CPUs can be controlled through
790 /sys/devices/system/cpu.
793 bool "Compat VDSO support"
796 Map the VDSO to the predictable old-style address too.
798 Say N here if you are running a sufficiently recent glibc
799 version (2.3.3 or later), to remove the high-mapped
800 VDSO mapping and to exclusively use the randomized VDSO.
806 config ARCH_ENABLE_MEMORY_HOTPLUG
810 menu "Power management options (ACPI, APM)"
811 depends on !X86_VOYAGER
813 source kernel/power/Kconfig
815 source "drivers/acpi/Kconfig"
817 menu "APM (Advanced Power Management) BIOS Support"
818 depends on PM && !X86_VISWS
821 tristate "APM (Advanced Power Management) BIOS support"
824 APM is a BIOS specification for saving power using several different
825 techniques. This is mostly useful for battery powered laptops with
826 APM compliant BIOSes. If you say Y here, the system time will be
827 reset after a RESUME operation, the /proc/apm device will provide
828 battery status information, and user-space programs will receive
829 notification of APM "events" (e.g. battery status change).
831 If you select "Y" here, you can disable actual use of the APM
832 BIOS by passing the "apm=off" option to the kernel at boot time.
834 Note that the APM support is almost completely disabled for
835 machines with more than one CPU.
837 In order to use APM, you will need supporting software. For location
838 and more information, read <file:Documentation/pm.txt> and the
839 Battery Powered Linux mini-HOWTO, available from
840 <http://www.tldp.org/docs.html#howto>.
842 This driver does not spin down disk drives (see the hdparm(8)
843 manpage ("man 8 hdparm") for that), and it doesn't turn off
844 VESA-compliant "green" monitors.
846 This driver does not support the TI 4000M TravelMate and the ACER
847 486/DX4/75 because they don't have compliant BIOSes. Many "green"
848 desktop machines also don't have compliant BIOSes, and this driver
849 may cause those machines to panic during the boot phase.
851 Generally, if you don't have a battery in your machine, there isn't
852 much point in using this driver and you should say N. If you get
853 random kernel OOPSes or reboots that don't seem to be related to
854 anything, try disabling/enabling this option (or disabling/enabling
857 Some other things you should try when experiencing seemingly random,
860 1) make sure that you have enough swap space and that it is
862 2) pass the "no-hlt" option to the kernel
863 3) switch on floating point emulation in the kernel and pass
864 the "no387" option to the kernel
865 4) pass the "floppy=nodma" option to the kernel
866 5) pass the "mem=4M" option to the kernel (thereby disabling
867 all but the first 4 MB of RAM)
868 6) make sure that the CPU is not over clocked.
869 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
870 8) disable the cache from your BIOS settings
871 9) install a fan for the video card or exchange video RAM
872 10) install a better fan for the CPU
873 11) exchange RAM chips
874 12) exchange the motherboard.
876 To compile this driver as a module, choose M here: the
877 module will be called apm.
879 config APM_IGNORE_USER_SUSPEND
880 bool "Ignore USER SUSPEND"
883 This option will ignore USER SUSPEND requests. On machines with a
884 compliant APM BIOS, you want to say N. However, on the NEC Versa M
885 series notebooks, it is necessary to say Y because of a BIOS bug.
888 bool "Enable PM at boot time"
891 Enable APM features at boot time. From page 36 of the APM BIOS
892 specification: "When disabled, the APM BIOS does not automatically
893 power manage devices, enter the Standby State, enter the Suspend
894 State, or take power saving steps in response to CPU Idle calls."
895 This driver will make CPU Idle calls when Linux is idle (unless this
896 feature is turned off -- see "Do CPU IDLE calls", below). This
897 should always save battery power, but more complicated APM features
898 will be dependent on your BIOS implementation. You may need to turn
899 this option off if your computer hangs at boot time when using APM
900 support, or if it beeps continuously instead of suspending. Turn
901 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
902 T400CDT. This is off by default since most machines do fine without
906 bool "Make CPU Idle calls when idle"
909 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
910 On some machines, this can activate improved power savings, such as
911 a slowed CPU clock rate, when the machine is idle. These idle calls
912 are made after the idle loop has run for some length of time (e.g.,
913 333 mS). On some machines, this will cause a hang at boot time or
914 whenever the CPU becomes idle. (On machines with more than one CPU,
915 this option does nothing.)
917 config APM_DISPLAY_BLANK
918 bool "Enable console blanking using APM"
921 Enable console blanking using the APM. Some laptops can use this to
922 turn off the LCD backlight when the screen blanker of the Linux
923 virtual console blanks the screen. Note that this is only used by
924 the virtual console screen blanker, and won't turn off the backlight
925 when using the X Window system. This also doesn't have anything to
926 do with your VESA-compliant power-saving monitor. Further, this
927 option doesn't work for all laptops -- it might not turn off your
928 backlight at all, or it might print a lot of errors to the console,
929 especially if you are using gpm.
931 config APM_RTC_IS_GMT
932 bool "RTC stores time in GMT"
935 Say Y here if your RTC (Real Time Clock a.k.a. hardware clock)
936 stores the time in GMT (Greenwich Mean Time). Say N if your RTC
939 It is in fact recommended to store GMT in your RTC, because then you
940 don't have to worry about daylight savings time changes. The only
941 reason not to use GMT in your RTC is if you also run a broken OS
942 that doesn't understand GMT.
944 config APM_ALLOW_INTS
945 bool "Allow interrupts during APM BIOS calls"
948 Normally we disable external interrupts while we are making calls to
949 the APM BIOS as a measure to lessen the effects of a badly behaving
950 BIOS implementation. The BIOS should reenable interrupts if it
951 needs to. Unfortunately, some BIOSes do not -- especially those in
952 many of the newer IBM Thinkpads. If you experience hangs when you
953 suspend, try setting this to Y. Otherwise, say N.
955 config APM_REAL_MODE_POWER_OFF
956 bool "Use real mode APM BIOS call to power off"
959 Use real mode APM BIOS calls to switch off the computer. This is
960 a work-around for a number of buggy BIOSes. Switch this option on if
961 your computer crashes instead of powering off properly.
965 source "arch/i386/kernel/cpu/cpufreq/Kconfig"
969 menu "Bus options (PCI, PCMCIA, EISA, MCA, ISA)"
972 bool "PCI support" if !X86_VISWS
973 depends on !X86_VOYAGER
974 default y if X86_VISWS
976 Find out whether you have a PCI motherboard. PCI is the name of a
977 bus system, i.e. the way the CPU talks to the other stuff inside
978 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
979 VESA. If you have PCI, say Y, otherwise N.
981 The PCI-HOWTO, available from
982 <http://www.tldp.org/docs.html#howto>, contains valuable
983 information about which PCI hardware does work under Linux and which
987 prompt "PCI access mode"
988 depends on PCI && !X86_VISWS
991 On PCI systems, the BIOS can be used to detect the PCI devices and
992 determine their configuration. However, some old PCI motherboards
993 have BIOS bugs and may crash if this is done. Also, some embedded
994 PCI-based systems don't have any BIOS at all. Linux can also try to
995 detect the PCI hardware directly without using the BIOS.
997 With this option, you can specify how Linux should detect the
998 PCI devices. If you choose "BIOS", the BIOS will be used,
999 if you choose "Direct", the BIOS won't be used, and if you
1000 choose "MMConfig", then PCI Express MMCONFIG will be used.
1001 If you choose "Any", the kernel will try MMCONFIG, then the
1002 direct access method and falls back to the BIOS if that doesn't
1003 work. If unsure, go with the default, which is "Any".
1008 config PCI_GOMMCONFIG
1021 depends on !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1026 depends on PCI && ((PCI_GODIRECT || PCI_GOANY) || X86_VISWS)
1031 depends on PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1034 source "drivers/pci/pcie/Kconfig"
1036 source "drivers/pci/Kconfig"
1044 depends on !(X86_VOYAGER || X86_VISWS)
1046 Find out whether you have ISA slots on your motherboard. ISA is the
1047 name of a bus system, i.e. the way the CPU talks to the other stuff
1048 inside your box. Other bus systems are PCI, EISA, MicroChannel
1049 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1050 newer boards don't support it. If you have ISA, say Y, otherwise N.
1056 The Extended Industry Standard Architecture (EISA) bus was
1057 developed as an open alternative to the IBM MicroChannel bus.
1059 The EISA bus provided some of the features of the IBM MicroChannel
1060 bus while maintaining backward compatibility with cards made for
1061 the older ISA bus. The EISA bus saw limited use between 1988 and
1062 1995 when it was made obsolete by the PCI bus.
1064 Say Y here if you are building a kernel for an EISA-based machine.
1068 source "drivers/eisa/Kconfig"
1071 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1072 default y if X86_VOYAGER
1074 MicroChannel Architecture is found in some IBM PS/2 machines and
1075 laptops. It is a bus system similar to PCI or ISA. See
1076 <file:Documentation/mca.txt> (and especially the web page given
1077 there) before attempting to build an MCA bus kernel.
1079 source "drivers/mca/Kconfig"
1082 tristate "NatSemi SCx200 support"
1083 depends on !X86_VOYAGER
1085 This provides basic support for National Semiconductor's
1086 (now AMD's) Geode processors. The driver probes for the
1087 PCI-IDs of several on-chip devices, so its a good dependency
1088 for other scx200_* drivers.
1090 If compiled as a module, the driver is named scx200.
1092 config SCx200HR_TIMER
1093 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1094 depends on SCx200 && GENERIC_TIME
1097 This driver provides a clocksource built upon the on-chip
1098 27MHz high-resolution timer. Its also a workaround for
1099 NSC Geode SC-1100's buggy TSC, which loses time when the
1100 processor goes idle (as is done by the scheduler). The
1101 other workaround is idle=poll boot option.
1105 depends on AGP_AMD64
1107 source "drivers/pcmcia/Kconfig"
1109 source "drivers/pci/hotplug/Kconfig"
1113 menu "Executable file formats"
1115 source "fs/Kconfig.binfmt"
1119 source "net/Kconfig"
1121 source "drivers/Kconfig"
1125 menu "Instrumentation Support"
1126 depends on EXPERIMENTAL
1128 source "arch/i386/oprofile/Kconfig"
1131 bool "Kprobes (EXPERIMENTAL)"
1132 depends on EXPERIMENTAL && MODULES
1134 Kprobes allows you to trap at almost any kernel address and
1135 execute a callback function. register_kprobe() establishes
1136 a probepoint and specifies the callback. Kprobes is useful
1137 for kernel debugging, non-intrusive instrumentation and testing.
1138 If in doubt, say "N".
1141 source "arch/i386/Kconfig.debug"
1143 source "security/Kconfig"
1145 source "crypto/Kconfig"
1147 source "lib/Kconfig"
1150 # Use the generic interrupt handling code in kernel/irq/:
1152 config GENERIC_HARDIRQS
1156 config GENERIC_IRQ_PROBE
1160 config GENERIC_PENDING_IRQ
1162 depends on GENERIC_HARDIRQS && SMP
1167 depends on SMP && !X86_VOYAGER
1172 depends on SMP && !(X86_VISWS || X86_VOYAGER)
1175 config X86_BIOS_REBOOT
1177 depends on !(X86_VISWS || X86_VOYAGER)
1180 config X86_TRAMPOLINE
1182 depends on X86_SMP || (X86_VOYAGER && SMP)
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