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.
145 If you want to build a NUMA kernel, you must select ACPI.
148 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
151 This option is needed for the systems that have more than 8 CPUs
152 and if the system is not of any sub-arch type above.
154 If you don't have such a system, you should say N here.
157 bool "SGI 320/540 (Visual Workstation)"
159 The SGI Visual Workstation series is an IA32-based workstation
160 based on SGI systems chips with some legacy PC hardware attached.
162 Say Y here to create a kernel to run on the SGI 320 or 540.
164 A kernel compiled for the Visual Workstation will not run on PCs
165 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
167 config X86_GENERICARCH
168 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
171 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
172 It is intended for a generic binary kernel.
173 If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
176 bool "Support for Unisys ES7000 IA32 series"
179 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
180 supposed to run on an IA32-based Unisys ES7000 system.
181 Only choose this option if you have such a system, otherwise you
189 depends on ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
192 config HAVE_ARCH_PARSE_SRAT
197 config X86_SUMMIT_NUMA
200 depends on NUMA && (X86_SUMMIT || X86_GENERICARCH)
202 config X86_CYCLONE_TIMER
205 depends on X86_SUMMIT || X86_GENERICARCH
207 config ES7000_CLUSTERED_APIC
210 depends on SMP && X86_ES7000 && MPENTIUMIII
212 source "arch/i386/Kconfig.cpu"
215 bool "HPET Timer Support"
217 This enables the use of the HPET for the kernel's internal timer.
218 HPET is the next generation timer replacing legacy 8254s.
219 You can safely choose Y here. However, HPET will only be
220 activated if the platform and the BIOS support this feature.
221 Otherwise the 8254 will be used for timing services.
223 Choose N to continue using the legacy 8254 timer.
225 config HPET_EMULATE_RTC
227 depends on HPET_TIMER && RTC=y
231 int "Maximum number of CPUs (2-255)"
234 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
237 This allows you to specify the maximum number of CPUs which this
238 kernel will support. The maximum supported value is 255 and the
239 minimum value which makes sense is 2.
241 This is purely to save memory - each supported CPU adds
242 approximately eight kilobytes to the kernel image.
245 bool "SMT (Hyperthreading) scheduler support"
248 SMT scheduler support improves the CPU scheduler's decision making
249 when dealing with Intel Pentium 4 chips with HyperThreading at a
250 cost of slightly increased overhead in some places. If unsure say
254 bool "Multi-core scheduler support"
258 Multi-core scheduler support improves the CPU scheduler's decision
259 making when dealing with multi-core CPU chips at a cost of slightly
260 increased overhead in some places. If unsure say N here.
262 source "kernel/Kconfig.preempt"
265 bool "Local APIC support on uniprocessors"
266 depends on !SMP && !(X86_VISWS || X86_VOYAGER)
268 A local APIC (Advanced Programmable Interrupt Controller) is an
269 integrated interrupt controller in the CPU. If you have a single-CPU
270 system which has a processor with a local APIC, you can say Y here to
271 enable and use it. If you say Y here even though your machine doesn't
272 have a local APIC, then the kernel will still run with no slowdown at
273 all. The local APIC supports CPU-generated self-interrupts (timer,
274 performance counters), and the NMI watchdog which detects hard
278 bool "IO-APIC support on uniprocessors"
279 depends on X86_UP_APIC
281 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
282 SMP-capable replacement for PC-style interrupt controllers. Most
283 SMP systems and many recent uniprocessor systems have one.
285 If you have a single-CPU system with an IO-APIC, you can say Y here
286 to use it. If you say Y here even though your machine doesn't have
287 an IO-APIC, then the kernel will still run with no slowdown at all.
289 config X86_LOCAL_APIC
291 depends on X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER)
296 depends on X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER))
299 config X86_VISWS_APIC
305 bool "Machine Check Exception"
306 depends on !X86_VOYAGER
308 Machine Check Exception support allows the processor to notify the
309 kernel if it detects a problem (e.g. overheating, component failure).
310 The action the kernel takes depends on the severity of the problem,
311 ranging from a warning message on the console, to halting the machine.
312 Your processor must be a Pentium or newer to support this - check the
313 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
314 have a design flaw which leads to false MCE events - hence MCE is
315 disabled on all P5 processors, unless explicitly enabled with "mce"
316 as a boot argument. Similarly, if MCE is built in and creates a
317 problem on some new non-standard machine, you can boot with "nomce"
318 to disable it. MCE support simply ignores non-MCE processors like
319 the 386 and 486, so nearly everyone can say Y here.
321 config X86_MCE_NONFATAL
322 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
325 Enabling this feature starts a timer that triggers every 5 seconds which
326 will look at the machine check registers to see if anything happened.
327 Non-fatal problems automatically get corrected (but still logged).
328 Disable this if you don't want to see these messages.
329 Seeing the messages this option prints out may be indicative of dying hardware,
330 or out-of-spec (ie, overclocked) hardware.
331 This option only does something on certain CPUs.
332 (AMD Athlon/Duron and Intel Pentium 4)
334 config X86_MCE_P4THERMAL
335 bool "check for P4 thermal throttling interrupt."
336 depends on X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
338 Enabling this feature will cause a message to be printed when the P4
339 enters thermal throttling.
343 bool "Enable VM86 support" if EMBEDDED
345 This option is required by programs like DOSEMU to run 16-bit legacy
346 code on X86 processors. It also may be needed by software like
347 XFree86 to initialize some video cards via BIOS. Disabling this
348 option saves about 6k.
351 tristate "Toshiba Laptop support"
353 This adds a driver to safely access the System Management Mode of
354 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
355 not work on models with a Phoenix BIOS. The System Management Mode
356 is used to set the BIOS and power saving options on Toshiba portables.
358 For information on utilities to make use of this driver see the
359 Toshiba Linux utilities web site at:
360 <http://www.buzzard.org.uk/toshiba/>.
362 Say Y if you intend to run this kernel on a Toshiba portable.
366 tristate "Dell laptop support"
368 This adds a driver to safely access the System Management Mode
369 of the CPU on the Dell Inspiron 8000. The System Management Mode
370 is used to read cpu temperature and cooling fan status and to
371 control the fans on the I8K portables.
373 This driver has been tested only on the Inspiron 8000 but it may
374 also work with other Dell laptops. You can force loading on other
375 models by passing the parameter `force=1' to the module. Use at
378 For information on utilities to make use of this driver see the
379 I8K Linux utilities web site at:
380 <http://people.debian.org/~dz/i8k/>
382 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
385 config X86_REBOOTFIXUPS
386 bool "Enable X86 board specific fixups for reboot"
390 This enables chipset and/or board specific fixups to be done
391 in order to get reboot to work correctly. This is only needed on
392 some combinations of hardware and BIOS. The symptom, for which
393 this config is intended, is when reboot ends with a stalled/hung
396 Currently, the only fixup is for the Geode GX1/CS5530A/TROM2.1.
399 Say Y if you want to enable the fixup. Currently, it's safe to
400 enable this option even if you don't need it.
404 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
406 If you say Y here and also to "/dev file system support" in the
407 'File systems' section, you will be able to update the microcode on
408 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
409 Pentium III, Pentium 4, Xeon etc. You will obviously need the
410 actual microcode binary data itself which is not shipped with the
413 For latest news and information on obtaining all the required
414 ingredients for this driver, check:
415 <http://www.urbanmyth.org/microcode/>.
417 To compile this driver as a module, choose M here: the
418 module will be called microcode.
421 tristate "/dev/cpu/*/msr - Model-specific register support"
423 This device gives privileged processes access to the x86
424 Model-Specific Registers (MSRs). It is a character device with
425 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
426 MSR accesses are directed to a specific CPU on multi-processor
430 tristate "/dev/cpu/*/cpuid - CPU information support"
432 This device gives processes access to the x86 CPUID instruction to
433 be executed on a specific processor. It is a character device
434 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
437 source "drivers/firmware/Kconfig"
440 prompt "High Memory Support"
445 depends on !X86_NUMAQ
447 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
448 However, the address space of 32-bit x86 processors is only 4
449 Gigabytes large. That means that, if you have a large amount of
450 physical memory, not all of it can be "permanently mapped" by the
451 kernel. The physical memory that's not permanently mapped is called
454 If you are compiling a kernel which will never run on a machine with
455 more than 1 Gigabyte total physical RAM, answer "off" here (default
456 choice and suitable for most users). This will result in a "3GB/1GB"
457 split: 3GB are mapped so that each process sees a 3GB virtual memory
458 space and the remaining part of the 4GB virtual memory space is used
459 by the kernel to permanently map as much physical memory as
462 If the machine has between 1 and 4 Gigabytes physical RAM, then
465 If more than 4 Gigabytes is used then answer "64GB" here. This
466 selection turns Intel PAE (Physical Address Extension) mode on.
467 PAE implements 3-level paging on IA32 processors. PAE is fully
468 supported by Linux, PAE mode is implemented on all recent Intel
469 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
470 then the kernel will not boot on CPUs that don't support PAE!
472 The actual amount of total physical memory will either be
473 auto detected or can be forced by using a kernel command line option
474 such as "mem=256M". (Try "man bootparam" or see the documentation of
475 your boot loader (lilo or loadlin) about how to pass options to the
476 kernel at boot time.)
478 If unsure, say "off".
482 depends on !X86_NUMAQ
484 Select this if you have a 32-bit processor and between 1 and 4
485 gigabytes of physical RAM.
489 depends on X86_CMPXCHG64
491 Select this if you have a 32-bit processor and more than 4
492 gigabytes of physical RAM.
497 depends on EXPERIMENTAL && !X86_PAE
498 prompt "Memory split" if EMBEDDED
501 Select the desired split between kernel and user memory.
503 If the address range available to the kernel is less than the
504 physical memory installed, the remaining memory will be available
505 as "high memory". Accessing high memory is a little more costly
506 than low memory, as it needs to be mapped into the kernel first.
507 Note that increasing the kernel address space limits the range
508 available to user programs, making the address space there
509 tighter. Selecting anything other than the default 3G/1G split
510 will also likely make your kernel incompatible with binary-only
513 If you are not absolutely sure what you are doing, leave this
517 bool "3G/1G user/kernel split"
518 config VMSPLIT_3G_OPT
519 bool "3G/1G user/kernel split (for full 1G low memory)"
521 bool "2G/2G user/kernel split"
523 bool "1G/3G user/kernel split"
528 default 0xB0000000 if VMSPLIT_3G_OPT
529 default 0x78000000 if VMSPLIT_2G
530 default 0x40000000 if VMSPLIT_1G
535 depends on HIGHMEM64G || HIGHMEM4G
540 depends on HIGHMEM64G
542 select RESOURCES_64BIT
544 # Common NUMA Features
546 bool "Numa Memory Allocation and Scheduler Support"
547 depends on SMP && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI)
549 default y if (X86_NUMAQ || X86_SUMMIT)
551 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
552 depends on X86_SUMMIT && (!HIGHMEM64G || !ACPI)
556 default "4" if X86_NUMAQ
558 depends on NEED_MULTIPLE_NODES
560 config HAVE_ARCH_BOOTMEM_NODE
565 config ARCH_HAVE_MEMORY_PRESENT
567 depends on DISCONTIGMEM
570 config NEED_NODE_MEMMAP_SIZE
572 depends on DISCONTIGMEM || SPARSEMEM
575 config HAVE_ARCH_ALLOC_REMAP
580 config ARCH_FLATMEM_ENABLE
582 depends on (ARCH_SELECT_MEMORY_MODEL && X86_PC)
584 config ARCH_DISCONTIGMEM_ENABLE
588 config ARCH_DISCONTIGMEM_DEFAULT
592 config ARCH_SPARSEMEM_ENABLE
594 depends on (NUMA || (X86_PC && EXPERIMENTAL))
595 select SPARSEMEM_STATIC
597 config ARCH_SELECT_MEMORY_MODEL
599 depends on ARCH_SPARSEMEM_ENABLE
603 config HAVE_ARCH_EARLY_PFN_TO_NID
609 bool "Allocate 3rd-level pagetables from highmem"
610 depends on HIGHMEM4G || HIGHMEM64G
612 The VM uses one page table entry for each page of physical memory.
613 For systems with a lot of RAM, this can be wasteful of precious
614 low memory. Setting this option will put user-space page table
615 entries in high memory.
617 config MATH_EMULATION
618 bool "Math emulation"
620 Linux can emulate a math coprocessor (used for floating point
621 operations) if you don't have one. 486DX and Pentium processors have
622 a math coprocessor built in, 486SX and 386 do not, unless you added
623 a 487DX or 387, respectively. (The messages during boot time can
624 give you some hints here ["man dmesg"].) Everyone needs either a
625 coprocessor or this emulation.
627 If you don't have a math coprocessor, you need to say Y here; if you
628 say Y here even though you have a coprocessor, the coprocessor will
629 be used nevertheless. (This behavior can be changed with the kernel
630 command line option "no387", which comes handy if your coprocessor
631 is broken. Try "man bootparam" or see the documentation of your boot
632 loader (lilo or loadlin) about how to pass options to the kernel at
633 boot time.) This means that it is a good idea to say Y here if you
634 intend to use this kernel on different machines.
636 More information about the internals of the Linux math coprocessor
637 emulation can be found in <file:arch/i386/math-emu/README>.
639 If you are not sure, say Y; apart from resulting in a 66 KB bigger
640 kernel, it won't hurt.
643 bool "MTRR (Memory Type Range Register) support"
645 On Intel P6 family processors (Pentium Pro, Pentium II and later)
646 the Memory Type Range Registers (MTRRs) may be used to control
647 processor access to memory ranges. This is most useful if you have
648 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
649 allows bus write transfers to be combined into a larger transfer
650 before bursting over the PCI/AGP bus. This can increase performance
651 of image write operations 2.5 times or more. Saying Y here creates a
652 /proc/mtrr file which may be used to manipulate your processor's
653 MTRRs. Typically the X server should use this.
655 This code has a reasonably generic interface so that similar
656 control registers on other processors can be easily supported
659 The Cyrix 6x86, 6x86MX and M II processors have Address Range
660 Registers (ARRs) which provide a similar functionality to MTRRs. For
661 these, the ARRs are used to emulate the MTRRs.
662 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
663 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
664 write-combining. All of these processors are supported by this code
665 and it makes sense to say Y here if you have one of them.
667 Saying Y here also fixes a problem with buggy SMP BIOSes which only
668 set the MTRRs for the boot CPU and not for the secondary CPUs. This
669 can lead to all sorts of problems, so it's good to say Y here.
671 You can safely say Y even if your machine doesn't have MTRRs, you'll
672 just add about 9 KB to your kernel.
674 See <file:Documentation/mtrr.txt> for more information.
677 bool "Boot from EFI support"
681 This enables the the kernel to boot on EFI platforms using
682 system configuration information passed to it from the firmware.
683 This also enables the kernel to use any EFI runtime services that are
684 available (such as the EFI variable services).
686 This option is only useful on systems that have EFI firmware
687 and will result in a kernel image that is ~8k larger. In addition,
688 you must use the latest ELILO loader available at
689 <http://elilo.sourceforge.net> in order to take advantage of
690 kernel initialization using EFI information (neither GRUB nor LILO know
691 anything about EFI). However, even with this option, the resultant
692 kernel should continue to boot on existing non-EFI platforms.
695 bool "Enable kernel irq balancing"
696 depends on SMP && X86_IO_APIC
699 The default yes will allow the kernel to do irq load balancing.
700 Saying no will keep the kernel from doing irq load balancing.
702 # turning this on wastes a bunch of space.
703 # Summit needs it only when NUMA is on
706 depends on (((X86_SUMMIT || X86_GENERICARCH) && NUMA) || (X86 && EFI))
710 bool "Use register arguments"
713 Compile the kernel with -mregparm=3. This instructs gcc to use
714 a more efficient function call ABI which passes the first three
715 arguments of a function call via registers, which results in denser
718 If this option is disabled, then the default ABI of passing
719 arguments via the stack is used.
724 bool "Enable seccomp to safely compute untrusted bytecode"
728 This kernel feature is useful for number crunching applications
729 that may need to compute untrusted bytecode during their
730 execution. By using pipes or other transports made available to
731 the process as file descriptors supporting the read/write
732 syscalls, it's possible to isolate those applications in
733 their own address space using seccomp. Once seccomp is
734 enabled via /proc/<pid>/seccomp, it cannot be disabled
735 and the task is only allowed to execute a few safe syscalls
736 defined by each seccomp mode.
738 If unsure, say Y. Only embedded should say N here.
740 source kernel/Kconfig.hz
743 bool "kexec system call (EXPERIMENTAL)"
744 depends on EXPERIMENTAL
746 kexec is a system call that implements the ability to shutdown your
747 current kernel, and to start another kernel. It is like a reboot
748 but it is independent of the system firmware. And like a reboot
749 you can start any kernel with it, not just Linux.
751 The name comes from the similarity to the exec system call.
753 It is an ongoing process to be certain the hardware in a machine
754 is properly shutdown, so do not be surprised if this code does not
755 initially work for you. It may help to enable device hotplugging
756 support. As of this writing the exact hardware interface is
757 strongly in flux, so no good recommendation can be made.
760 bool "kernel crash dumps (EXPERIMENTAL)"
761 depends on EXPERIMENTAL
764 Generate crash dump after being started by kexec.
766 config PHYSICAL_START
767 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
769 default "0x1000000" if CRASH_DUMP
772 This gives the physical address where the kernel is loaded. Normally
773 for regular kernels this value is 0x100000 (1MB). But in the case
774 of kexec on panic the fail safe kernel needs to run at a different
775 address than the panic-ed kernel. This option is used to set the load
776 address for kernels used to capture crash dump on being kexec'ed
777 after panic. The default value for crash dump kernels is
778 0x1000000 (16MB). This can also be set based on the "X" value as
779 specified in the "crashkernel=YM@XM" command line boot parameter
780 passed to the panic-ed kernel. Typically this parameter is set as
781 crashkernel=64M@16M. Please take a look at
782 Documentation/kdump/kdump.txt for more details about crash dumps.
784 Don't change this unless you know what you are doing.
787 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
788 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
790 Say Y here to experiment with turning CPUs off and on, and to
791 enable suspend on SMP systems. CPUs can be controlled through
792 /sys/devices/system/cpu.
795 bool "Compat VDSO support"
798 Map the VDSO to the predictable old-style address too.
800 Say N here if you are running a sufficiently recent glibc
801 version (2.3.3 or later), to remove the high-mapped
802 VDSO mapping and to exclusively use the randomized VDSO.
808 config ARCH_ENABLE_MEMORY_HOTPLUG
812 menu "Power management options (ACPI, APM)"
813 depends on !X86_VOYAGER
815 source kernel/power/Kconfig
817 source "drivers/acpi/Kconfig"
819 menu "APM (Advanced Power Management) BIOS Support"
820 depends on PM && !X86_VISWS
823 tristate "APM (Advanced Power Management) BIOS support"
826 APM is a BIOS specification for saving power using several different
827 techniques. This is mostly useful for battery powered laptops with
828 APM compliant BIOSes. If you say Y here, the system time will be
829 reset after a RESUME operation, the /proc/apm device will provide
830 battery status information, and user-space programs will receive
831 notification of APM "events" (e.g. battery status change).
833 If you select "Y" here, you can disable actual use of the APM
834 BIOS by passing the "apm=off" option to the kernel at boot time.
836 Note that the APM support is almost completely disabled for
837 machines with more than one CPU.
839 In order to use APM, you will need supporting software. For location
840 and more information, read <file:Documentation/pm.txt> and the
841 Battery Powered Linux mini-HOWTO, available from
842 <http://www.tldp.org/docs.html#howto>.
844 This driver does not spin down disk drives (see the hdparm(8)
845 manpage ("man 8 hdparm") for that), and it doesn't turn off
846 VESA-compliant "green" monitors.
848 This driver does not support the TI 4000M TravelMate and the ACER
849 486/DX4/75 because they don't have compliant BIOSes. Many "green"
850 desktop machines also don't have compliant BIOSes, and this driver
851 may cause those machines to panic during the boot phase.
853 Generally, if you don't have a battery in your machine, there isn't
854 much point in using this driver and you should say N. If you get
855 random kernel OOPSes or reboots that don't seem to be related to
856 anything, try disabling/enabling this option (or disabling/enabling
859 Some other things you should try when experiencing seemingly random,
862 1) make sure that you have enough swap space and that it is
864 2) pass the "no-hlt" option to the kernel
865 3) switch on floating point emulation in the kernel and pass
866 the "no387" option to the kernel
867 4) pass the "floppy=nodma" option to the kernel
868 5) pass the "mem=4M" option to the kernel (thereby disabling
869 all but the first 4 MB of RAM)
870 6) make sure that the CPU is not over clocked.
871 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
872 8) disable the cache from your BIOS settings
873 9) install a fan for the video card or exchange video RAM
874 10) install a better fan for the CPU
875 11) exchange RAM chips
876 12) exchange the motherboard.
878 To compile this driver as a module, choose M here: the
879 module will be called apm.
881 config APM_IGNORE_USER_SUSPEND
882 bool "Ignore USER SUSPEND"
885 This option will ignore USER SUSPEND requests. On machines with a
886 compliant APM BIOS, you want to say N. However, on the NEC Versa M
887 series notebooks, it is necessary to say Y because of a BIOS bug.
890 bool "Enable PM at boot time"
893 Enable APM features at boot time. From page 36 of the APM BIOS
894 specification: "When disabled, the APM BIOS does not automatically
895 power manage devices, enter the Standby State, enter the Suspend
896 State, or take power saving steps in response to CPU Idle calls."
897 This driver will make CPU Idle calls when Linux is idle (unless this
898 feature is turned off -- see "Do CPU IDLE calls", below). This
899 should always save battery power, but more complicated APM features
900 will be dependent on your BIOS implementation. You may need to turn
901 this option off if your computer hangs at boot time when using APM
902 support, or if it beeps continuously instead of suspending. Turn
903 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
904 T400CDT. This is off by default since most machines do fine without
908 bool "Make CPU Idle calls when idle"
911 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
912 On some machines, this can activate improved power savings, such as
913 a slowed CPU clock rate, when the machine is idle. These idle calls
914 are made after the idle loop has run for some length of time (e.g.,
915 333 mS). On some machines, this will cause a hang at boot time or
916 whenever the CPU becomes idle. (On machines with more than one CPU,
917 this option does nothing.)
919 config APM_DISPLAY_BLANK
920 bool "Enable console blanking using APM"
923 Enable console blanking using the APM. Some laptops can use this to
924 turn off the LCD backlight when the screen blanker of the Linux
925 virtual console blanks the screen. Note that this is only used by
926 the virtual console screen blanker, and won't turn off the backlight
927 when using the X Window system. This also doesn't have anything to
928 do with your VESA-compliant power-saving monitor. Further, this
929 option doesn't work for all laptops -- it might not turn off your
930 backlight at all, or it might print a lot of errors to the console,
931 especially if you are using gpm.
933 config APM_RTC_IS_GMT
934 bool "RTC stores time in GMT"
937 Say Y here if your RTC (Real Time Clock a.k.a. hardware clock)
938 stores the time in GMT (Greenwich Mean Time). Say N if your RTC
941 It is in fact recommended to store GMT in your RTC, because then you
942 don't have to worry about daylight savings time changes. The only
943 reason not to use GMT in your RTC is if you also run a broken OS
944 that doesn't understand GMT.
946 config APM_ALLOW_INTS
947 bool "Allow interrupts during APM BIOS calls"
950 Normally we disable external interrupts while we are making calls to
951 the APM BIOS as a measure to lessen the effects of a badly behaving
952 BIOS implementation. The BIOS should reenable interrupts if it
953 needs to. Unfortunately, some BIOSes do not -- especially those in
954 many of the newer IBM Thinkpads. If you experience hangs when you
955 suspend, try setting this to Y. Otherwise, say N.
957 config APM_REAL_MODE_POWER_OFF
958 bool "Use real mode APM BIOS call to power off"
961 Use real mode APM BIOS calls to switch off the computer. This is
962 a work-around for a number of buggy BIOSes. Switch this option on if
963 your computer crashes instead of powering off properly.
967 source "arch/i386/kernel/cpu/cpufreq/Kconfig"
971 menu "Bus options (PCI, PCMCIA, EISA, MCA, ISA)"
974 bool "PCI support" if !X86_VISWS
975 depends on !X86_VOYAGER
976 default y if X86_VISWS
978 Find out whether you have a PCI motherboard. PCI is the name of a
979 bus system, i.e. the way the CPU talks to the other stuff inside
980 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
981 VESA. If you have PCI, say Y, otherwise N.
983 The PCI-HOWTO, available from
984 <http://www.tldp.org/docs.html#howto>, contains valuable
985 information about which PCI hardware does work under Linux and which
989 prompt "PCI access mode"
990 depends on PCI && !X86_VISWS
993 On PCI systems, the BIOS can be used to detect the PCI devices and
994 determine their configuration. However, some old PCI motherboards
995 have BIOS bugs and may crash if this is done. Also, some embedded
996 PCI-based systems don't have any BIOS at all. Linux can also try to
997 detect the PCI hardware directly without using the BIOS.
999 With this option, you can specify how Linux should detect the
1000 PCI devices. If you choose "BIOS", the BIOS will be used,
1001 if you choose "Direct", the BIOS won't be used, and if you
1002 choose "MMConfig", then PCI Express MMCONFIG will be used.
1003 If you choose "Any", the kernel will try MMCONFIG, then the
1004 direct access method and falls back to the BIOS if that doesn't
1005 work. If unsure, go with the default, which is "Any".
1010 config PCI_GOMMCONFIG
1023 depends on !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1028 depends on PCI && ((PCI_GODIRECT || PCI_GOANY) || X86_VISWS)
1033 depends on PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1036 source "drivers/pci/pcie/Kconfig"
1038 source "drivers/pci/Kconfig"
1046 depends on !(X86_VOYAGER || X86_VISWS)
1048 Find out whether you have ISA slots on your motherboard. ISA is the
1049 name of a bus system, i.e. the way the CPU talks to the other stuff
1050 inside your box. Other bus systems are PCI, EISA, MicroChannel
1051 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1052 newer boards don't support it. If you have ISA, say Y, otherwise N.
1058 The Extended Industry Standard Architecture (EISA) bus was
1059 developed as an open alternative to the IBM MicroChannel bus.
1061 The EISA bus provided some of the features of the IBM MicroChannel
1062 bus while maintaining backward compatibility with cards made for
1063 the older ISA bus. The EISA bus saw limited use between 1988 and
1064 1995 when it was made obsolete by the PCI bus.
1066 Say Y here if you are building a kernel for an EISA-based machine.
1070 source "drivers/eisa/Kconfig"
1073 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1074 default y if X86_VOYAGER
1076 MicroChannel Architecture is found in some IBM PS/2 machines and
1077 laptops. It is a bus system similar to PCI or ISA. See
1078 <file:Documentation/mca.txt> (and especially the web page given
1079 there) before attempting to build an MCA bus kernel.
1081 source "drivers/mca/Kconfig"
1084 tristate "NatSemi SCx200 support"
1085 depends on !X86_VOYAGER
1087 This provides basic support for National Semiconductor's
1088 (now AMD's) Geode processors. The driver probes for the
1089 PCI-IDs of several on-chip devices, so its a good dependency
1090 for other scx200_* drivers.
1092 If compiled as a module, the driver is named scx200.
1094 config SCx200HR_TIMER
1095 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1096 depends on SCx200 && GENERIC_TIME
1099 This driver provides a clocksource built upon the on-chip
1100 27MHz high-resolution timer. Its also a workaround for
1101 NSC Geode SC-1100's buggy TSC, which loses time when the
1102 processor goes idle (as is done by the scheduler). The
1103 other workaround is idle=poll boot option.
1107 depends on AGP_AMD64
1109 source "drivers/pcmcia/Kconfig"
1111 source "drivers/pci/hotplug/Kconfig"
1115 menu "Executable file formats"
1117 source "fs/Kconfig.binfmt"
1121 source "net/Kconfig"
1123 source "drivers/Kconfig"
1127 menu "Instrumentation Support"
1128 depends on EXPERIMENTAL
1130 source "arch/i386/oprofile/Kconfig"
1133 bool "Kprobes (EXPERIMENTAL)"
1134 depends on EXPERIMENTAL && MODULES
1136 Kprobes allows you to trap at almost any kernel address and
1137 execute a callback function. register_kprobe() establishes
1138 a probepoint and specifies the callback. Kprobes is useful
1139 for kernel debugging, non-intrusive instrumentation and testing.
1140 If in doubt, say "N".
1143 source "arch/i386/Kconfig.debug"
1145 source "security/Kconfig"
1147 source "crypto/Kconfig"
1149 source "lib/Kconfig"
1152 # Use the generic interrupt handling code in kernel/irq/:
1154 config GENERIC_HARDIRQS
1158 config GENERIC_IRQ_PROBE
1162 config GENERIC_PENDING_IRQ
1164 depends on GENERIC_HARDIRQS && SMP
1169 depends on SMP && !X86_VOYAGER
1174 depends on SMP && !(X86_VISWS || X86_VOYAGER)
1177 config X86_BIOS_REBOOT
1179 depends on !(X86_VISWS || X86_VOYAGER)
1182 config X86_TRAMPOLINE
1184 depends on X86_SMP || (X86_VOYAGER && SMP)
projects / linux-2.6 / blob