2 # For a description of the syntax of this configuration file,
3 # see Documentation/kbuild/kconfig-language.txt.
6 mainmenu "Linux Kernel Configuration"
12 This is Linux's home port. Linux was originally native to the Intel
13 386, and runs on all the later x86 processors including the Intel
14 486, 586, Pentiums, and various instruction-set-compatible chips by
15 AMD, Cyrix, and others.
17 config SEMAPHORE_SLEEPERS
32 config GENERIC_ISA_DMA
40 config GENERIC_HWEIGHT
44 config ARCH_MAY_HAVE_PC_FDC
54 menu "Processor type and features"
57 bool "Symmetric multi-processing support"
59 This enables support for systems with more than one CPU. If you have
60 a system with only one CPU, like most personal computers, say N. If
61 you have a system with more than one CPU, say Y.
63 If you say N here, the kernel will run on single and multiprocessor
64 machines, but will use only one CPU of a multiprocessor machine. If
65 you say Y here, the kernel will run on many, but not all,
66 singleprocessor machines. On a singleprocessor machine, the kernel
67 will run faster if you say N here.
69 Note that if you say Y here and choose architecture "586" or
70 "Pentium" under "Processor family", the kernel will not work on 486
71 architectures. Similarly, multiprocessor kernels for the "PPro"
72 architecture may not work on all Pentium based boards.
74 People using multiprocessor machines who say Y here should also say
75 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
76 Management" code will be disabled if you say Y here.
78 See also the <file:Documentation/smp.txt>,
79 <file:Documentation/i386/IO-APIC.txt>,
80 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
81 <http://www.tldp.org/docs.html#howto>.
83 If you don't know what to do here, say N.
86 prompt "Subarchitecture Type"
92 Choose this option if your computer is a standard PC or compatible.
97 Select this for an AMD Elan processor.
99 Do not use this option for K6/Athlon/Opteron processors!
101 If unsure, choose "PC-compatible" instead.
106 Voyager is an MCA-based 32-way capable SMP architecture proprietary
107 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
111 If you do not specifically know you have a Voyager based machine,
112 say N here, otherwise the kernel you build will not be bootable.
115 bool "NUMAQ (IBM/Sequent)"
119 This option is used for getting Linux to run on a (IBM/Sequent) NUMA
120 multiquad box. This changes the way that processors are bootstrapped,
121 and uses Clustered Logical APIC addressing mode instead of Flat Logical.
122 You will need a new lynxer.elf file to flash your firmware with - send
123 email to <Martin.Bligh@us.ibm.com>.
126 bool "Summit/EXA (IBM x440)"
129 This option is needed for IBM systems that use the Summit/EXA chipset.
130 In particular, it is needed for the x440.
132 If you don't have one of these computers, you should say N here.
135 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
138 This option is needed for the systems that have more than 8 CPUs
139 and if the system is not of any sub-arch type above.
141 If you don't have such a system, you should say N here.
144 bool "SGI 320/540 (Visual Workstation)"
146 The SGI Visual Workstation series is an IA32-based workstation
147 based on SGI systems chips with some legacy PC hardware attached.
149 Say Y here to create a kernel to run on the SGI 320 or 540.
151 A kernel compiled for the Visual Workstation will not run on PCs
152 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
154 config X86_GENERICARCH
155 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
158 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
159 It is intended for a generic binary kernel.
162 bool "Support for Unisys ES7000 IA32 series"
165 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
166 supposed to run on an IA32-based Unisys ES7000 system.
167 Only choose this option if you have such a system, otherwise you
175 depends on NUMA && (X86_SUMMIT || X86_GENERICARCH)
178 config HAVE_ARCH_PARSE_SRAT
183 config X86_SUMMIT_NUMA
186 depends on NUMA && (X86_SUMMIT || X86_GENERICARCH)
188 config X86_CYCLONE_TIMER
191 depends on X86_SUMMIT || X86_GENERICARCH
193 config ES7000_CLUSTERED_APIC
196 depends on SMP && X86_ES7000 && MPENTIUMIII
198 source "arch/i386/Kconfig.cpu"
201 bool "HPET Timer Support"
203 This enables the use of the HPET for the kernel's internal timer.
204 HPET is the next generation timer replacing legacy 8254s.
205 You can safely choose Y here. However, HPET will only be
206 activated if the platform and the BIOS support this feature.
207 Otherwise the 8254 will be used for timing services.
209 Choose N to continue using the legacy 8254 timer.
211 config HPET_EMULATE_RTC
213 depends on HPET_TIMER && RTC=y
217 int "Maximum number of CPUs (2-255)"
220 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
223 This allows you to specify the maximum number of CPUs which this
224 kernel will support. The maximum supported value is 255 and the
225 minimum value which makes sense is 2.
227 This is purely to save memory - each supported CPU adds
228 approximately eight kilobytes to the kernel image.
231 bool "SMT (Hyperthreading) scheduler support"
234 SMT scheduler support improves the CPU scheduler's decision making
235 when dealing with Intel Pentium 4 chips with HyperThreading at a
236 cost of slightly increased overhead in some places. If unsure say
240 bool "Multi-core scheduler support"
244 Multi-core scheduler support improves the CPU scheduler's decision
245 making when dealing with multi-core CPU chips at a cost of slightly
246 increased overhead in some places. If unsure say N here.
248 source "kernel/Kconfig.preempt"
251 bool "Local APIC support on uniprocessors"
252 depends on !SMP && !(X86_VISWS || X86_VOYAGER)
254 A local APIC (Advanced Programmable Interrupt Controller) is an
255 integrated interrupt controller in the CPU. If you have a single-CPU
256 system which has a processor with a local APIC, you can say Y here to
257 enable and use it. If you say Y here even though your machine doesn't
258 have a local APIC, then the kernel will still run with no slowdown at
259 all. The local APIC supports CPU-generated self-interrupts (timer,
260 performance counters), and the NMI watchdog which detects hard
264 bool "IO-APIC support on uniprocessors"
265 depends on X86_UP_APIC
267 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
268 SMP-capable replacement for PC-style interrupt controllers. Most
269 SMP systems and many recent uniprocessor systems have one.
271 If you have a single-CPU system with an IO-APIC, you can say Y here
272 to use it. If you say Y here even though your machine doesn't have
273 an IO-APIC, then the kernel will still run with no slowdown at all.
275 config X86_LOCAL_APIC
277 depends on X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER)
282 depends on X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER))
285 config X86_VISWS_APIC
291 bool "Machine Check Exception"
292 depends on !X86_VOYAGER
294 Machine Check Exception support allows the processor to notify the
295 kernel if it detects a problem (e.g. overheating, component failure).
296 The action the kernel takes depends on the severity of the problem,
297 ranging from a warning message on the console, to halting the machine.
298 Your processor must be a Pentium or newer to support this - check the
299 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
300 have a design flaw which leads to false MCE events - hence MCE is
301 disabled on all P5 processors, unless explicitly enabled with "mce"
302 as a boot argument. Similarly, if MCE is built in and creates a
303 problem on some new non-standard machine, you can boot with "nomce"
304 to disable it. MCE support simply ignores non-MCE processors like
305 the 386 and 486, so nearly everyone can say Y here.
307 config X86_MCE_NONFATAL
308 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
311 Enabling this feature starts a timer that triggers every 5 seconds which
312 will look at the machine check registers to see if anything happened.
313 Non-fatal problems automatically get corrected (but still logged).
314 Disable this if you don't want to see these messages.
315 Seeing the messages this option prints out may be indicative of dying hardware,
316 or out-of-spec (ie, overclocked) hardware.
317 This option only does something on certain CPUs.
318 (AMD Athlon/Duron and Intel Pentium 4)
320 config X86_MCE_P4THERMAL
321 bool "check for P4 thermal throttling interrupt."
322 depends on X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
324 Enabling this feature will cause a message to be printed when the P4
325 enters thermal throttling.
328 tristate "Toshiba Laptop support"
330 This adds a driver to safely access the System Management Mode of
331 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
332 not work on models with a Phoenix BIOS. The System Management Mode
333 is used to set the BIOS and power saving options on Toshiba portables.
335 For information on utilities to make use of this driver see the
336 Toshiba Linux utilities web site at:
337 <http://www.buzzard.org.uk/toshiba/>.
339 Say Y if you intend to run this kernel on a Toshiba portable.
343 tristate "Dell laptop support"
345 This adds a driver to safely access the System Management Mode
346 of the CPU on the Dell Inspiron 8000. The System Management Mode
347 is used to read cpu temperature and cooling fan status and to
348 control the fans on the I8K portables.
350 This driver has been tested only on the Inspiron 8000 but it may
351 also work with other Dell laptops. You can force loading on other
352 models by passing the parameter `force=1' to the module. Use at
355 For information on utilities to make use of this driver see the
356 I8K Linux utilities web site at:
357 <http://people.debian.org/~dz/i8k/>
359 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
362 config X86_REBOOTFIXUPS
363 bool "Enable X86 board specific fixups for reboot"
367 This enables chipset and/or board specific fixups to be done
368 in order to get reboot to work correctly. This is only needed on
369 some combinations of hardware and BIOS. The symptom, for which
370 this config is intended, is when reboot ends with a stalled/hung
373 Currently, the only fixup is for the Geode GX1/CS5530A/TROM2.1.
376 Say Y if you want to enable the fixup. Currently, it's safe to
377 enable this option even if you don't need it.
381 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
383 If you say Y here and also to "/dev file system support" in the
384 'File systems' section, you will be able to update the microcode on
385 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
386 Pentium III, Pentium 4, Xeon etc. You will obviously need the
387 actual microcode binary data itself which is not shipped with the
390 For latest news and information on obtaining all the required
391 ingredients for this driver, check:
392 <http://www.urbanmyth.org/microcode/>.
394 To compile this driver as a module, choose M here: the
395 module will be called microcode.
398 tristate "/dev/cpu/*/msr - Model-specific register support"
400 This device gives privileged processes access to the x86
401 Model-Specific Registers (MSRs). It is a character device with
402 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
403 MSR accesses are directed to a specific CPU on multi-processor
407 tristate "/dev/cpu/*/cpuid - CPU information support"
409 This device gives processes access to the x86 CPUID instruction to
410 be executed on a specific processor. It is a character device
411 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
414 source "drivers/firmware/Kconfig"
417 prompt "High Memory Support"
422 depends on !X86_NUMAQ
424 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
425 However, the address space of 32-bit x86 processors is only 4
426 Gigabytes large. That means that, if you have a large amount of
427 physical memory, not all of it can be "permanently mapped" by the
428 kernel. The physical memory that's not permanently mapped is called
431 If you are compiling a kernel which will never run on a machine with
432 more than 1 Gigabyte total physical RAM, answer "off" here (default
433 choice and suitable for most users). This will result in a "3GB/1GB"
434 split: 3GB are mapped so that each process sees a 3GB virtual memory
435 space and the remaining part of the 4GB virtual memory space is used
436 by the kernel to permanently map as much physical memory as
439 If the machine has between 1 and 4 Gigabytes physical RAM, then
442 If more than 4 Gigabytes is used then answer "64GB" here. This
443 selection turns Intel PAE (Physical Address Extension) mode on.
444 PAE implements 3-level paging on IA32 processors. PAE is fully
445 supported by Linux, PAE mode is implemented on all recent Intel
446 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
447 then the kernel will not boot on CPUs that don't support PAE!
449 The actual amount of total physical memory will either be
450 auto detected or can be forced by using a kernel command line option
451 such as "mem=256M". (Try "man bootparam" or see the documentation of
452 your boot loader (lilo or loadlin) about how to pass options to the
453 kernel at boot time.)
455 If unsure, say "off".
459 depends on !X86_NUMAQ
461 Select this if you have a 32-bit processor and between 1 and 4
462 gigabytes of physical RAM.
466 depends on X86_CMPXCHG64
468 Select this if you have a 32-bit processor and more than 4
469 gigabytes of physical RAM.
474 depends on EXPERIMENTAL && !X86_PAE
475 prompt "Memory split" if EMBEDDED
478 Select the desired split between kernel and user memory.
480 If the address range available to the kernel is less than the
481 physical memory installed, the remaining memory will be available
482 as "high memory". Accessing high memory is a little more costly
483 than low memory, as it needs to be mapped into the kernel first.
484 Note that increasing the kernel address space limits the range
485 available to user programs, making the address space there
486 tighter. Selecting anything other than the default 3G/1G split
487 will also likely make your kernel incompatible with binary-only
490 If you are not absolutely sure what you are doing, leave this
494 bool "3G/1G user/kernel split"
495 config VMSPLIT_3G_OPT
496 bool "3G/1G user/kernel split (for full 1G low memory)"
498 bool "2G/2G user/kernel split"
500 bool "1G/3G user/kernel split"
505 default 0xB0000000 if VMSPLIT_3G_OPT
506 default 0x78000000 if VMSPLIT_2G
507 default 0x40000000 if VMSPLIT_1G
512 depends on HIGHMEM64G || HIGHMEM4G
517 depends on HIGHMEM64G
520 # Common NUMA Features
522 bool "Numa Memory Allocation and Scheduler Support"
523 depends on SMP && HIGHMEM64G && (X86_NUMAQ || X86_GENERICARCH || (X86_SUMMIT && ACPI))
525 default y if (X86_NUMAQ || X86_SUMMIT)
527 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
528 depends on X86_SUMMIT && (!HIGHMEM64G || !ACPI)
532 default "4" if X86_NUMAQ
534 depends on NEED_MULTIPLE_NODES
536 config HAVE_ARCH_BOOTMEM_NODE
541 config ARCH_HAVE_MEMORY_PRESENT
543 depends on DISCONTIGMEM
546 config NEED_NODE_MEMMAP_SIZE
548 depends on DISCONTIGMEM || SPARSEMEM
551 config HAVE_ARCH_ALLOC_REMAP
556 config ARCH_FLATMEM_ENABLE
558 depends on (ARCH_SELECT_MEMORY_MODEL && X86_PC)
560 config ARCH_DISCONTIGMEM_ENABLE
564 config ARCH_DISCONTIGMEM_DEFAULT
568 config ARCH_SPARSEMEM_ENABLE
570 depends on (NUMA || (X86_PC && EXPERIMENTAL))
571 select SPARSEMEM_STATIC
573 config ARCH_SELECT_MEMORY_MODEL
575 depends on ARCH_SPARSEMEM_ENABLE
579 config HAVE_ARCH_EARLY_PFN_TO_NID
585 bool "Allocate 3rd-level pagetables from highmem"
586 depends on HIGHMEM4G || HIGHMEM64G
588 The VM uses one page table entry for each page of physical memory.
589 For systems with a lot of RAM, this can be wasteful of precious
590 low memory. Setting this option will put user-space page table
591 entries in high memory.
593 config MATH_EMULATION
594 bool "Math emulation"
596 Linux can emulate a math coprocessor (used for floating point
597 operations) if you don't have one. 486DX and Pentium processors have
598 a math coprocessor built in, 486SX and 386 do not, unless you added
599 a 487DX or 387, respectively. (The messages during boot time can
600 give you some hints here ["man dmesg"].) Everyone needs either a
601 coprocessor or this emulation.
603 If you don't have a math coprocessor, you need to say Y here; if you
604 say Y here even though you have a coprocessor, the coprocessor will
605 be used nevertheless. (This behavior can be changed with the kernel
606 command line option "no387", which comes handy if your coprocessor
607 is broken. Try "man bootparam" or see the documentation of your boot
608 loader (lilo or loadlin) about how to pass options to the kernel at
609 boot time.) This means that it is a good idea to say Y here if you
610 intend to use this kernel on different machines.
612 More information about the internals of the Linux math coprocessor
613 emulation can be found in <file:arch/i386/math-emu/README>.
615 If you are not sure, say Y; apart from resulting in a 66 KB bigger
616 kernel, it won't hurt.
619 bool "MTRR (Memory Type Range Register) support"
621 On Intel P6 family processors (Pentium Pro, Pentium II and later)
622 the Memory Type Range Registers (MTRRs) may be used to control
623 processor access to memory ranges. This is most useful if you have
624 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
625 allows bus write transfers to be combined into a larger transfer
626 before bursting over the PCI/AGP bus. This can increase performance
627 of image write operations 2.5 times or more. Saying Y here creates a
628 /proc/mtrr file which may be used to manipulate your processor's
629 MTRRs. Typically the X server should use this.
631 This code has a reasonably generic interface so that similar
632 control registers on other processors can be easily supported
635 The Cyrix 6x86, 6x86MX and M II processors have Address Range
636 Registers (ARRs) which provide a similar functionality to MTRRs. For
637 these, the ARRs are used to emulate the MTRRs.
638 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
639 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
640 write-combining. All of these processors are supported by this code
641 and it makes sense to say Y here if you have one of them.
643 Saying Y here also fixes a problem with buggy SMP BIOSes which only
644 set the MTRRs for the boot CPU and not for the secondary CPUs. This
645 can lead to all sorts of problems, so it's good to say Y here.
647 You can safely say Y even if your machine doesn't have MTRRs, you'll
648 just add about 9 KB to your kernel.
650 See <file:Documentation/mtrr.txt> for more information.
653 bool "Boot from EFI support (EXPERIMENTAL)"
657 This enables the the kernel to boot on EFI platforms using
658 system configuration information passed to it from the firmware.
659 This also enables the kernel to use any EFI runtime services that are
660 available (such as the EFI variable services).
662 This option is only useful on systems that have EFI firmware
663 and will result in a kernel image that is ~8k larger. In addition,
664 you must use the latest ELILO loader available at
665 <http://elilo.sourceforge.net> in order to take advantage of
666 kernel initialization using EFI information (neither GRUB nor LILO know
667 anything about EFI). However, even with this option, the resultant
668 kernel should continue to boot on existing non-EFI platforms.
671 bool "Enable kernel irq balancing"
672 depends on SMP && X86_IO_APIC
675 The default yes will allow the kernel to do irq load balancing.
676 Saying no will keep the kernel from doing irq load balancing.
678 # turning this on wastes a bunch of space.
679 # Summit needs it only when NUMA is on
682 depends on (((X86_SUMMIT || X86_GENERICARCH) && NUMA) || (X86 && EFI))
686 bool "Use register arguments"
689 Compile the kernel with -mregparm=3. This instructs gcc to use
690 a more efficient function call ABI which passes the first three
691 arguments of a function call via registers, which results in denser
694 If this option is disabled, then the default ABI of passing
695 arguments via the stack is used.
700 bool "Enable seccomp to safely compute untrusted bytecode"
704 This kernel feature is useful for number crunching applications
705 that may need to compute untrusted bytecode during their
706 execution. By using pipes or other transports made available to
707 the process as file descriptors supporting the read/write
708 syscalls, it's possible to isolate those applications in
709 their own address space using seccomp. Once seccomp is
710 enabled via /proc/<pid>/seccomp, it cannot be disabled
711 and the task is only allowed to execute a few safe syscalls
712 defined by each seccomp mode.
714 If unsure, say Y. Only embedded should say N here.
716 source kernel/Kconfig.hz
719 bool "kexec system call (EXPERIMENTAL)"
720 depends on EXPERIMENTAL
722 kexec is a system call that implements the ability to shutdown your
723 current kernel, and to start another kernel. It is like a reboot
724 but it is indepedent of the system firmware. And like a reboot
725 you can start any kernel with it, not just Linux.
727 The name comes from the similiarity to the exec system call.
729 It is an ongoing process to be certain the hardware in a machine
730 is properly shutdown, so do not be surprised if this code does not
731 initially work for you. It may help to enable device hotplugging
732 support. As of this writing the exact hardware interface is
733 strongly in flux, so no good recommendation can be made.
736 bool "kernel crash dumps (EXPERIMENTAL)"
737 depends on EXPERIMENTAL
740 Generate crash dump after being started by kexec.
742 config PHYSICAL_START
743 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
745 default "0x1000000" if CRASH_DUMP
748 This gives the physical address where the kernel is loaded. Normally
749 for regular kernels this value is 0x100000 (1MB). But in the case
750 of kexec on panic the fail safe kernel needs to run at a different
751 address than the panic-ed kernel. This option is used to set the load
752 address for kernels used to capture crash dump on being kexec'ed
753 after panic. The default value for crash dump kernels is
754 0x1000000 (16MB). This can also be set based on the "X" value as
755 specified in the "crashkernel=YM@XM" command line boot parameter
756 passed to the panic-ed kernel. Typically this parameter is set as
757 crashkernel=64M@16M. Please take a look at
758 Documentation/kdump/kdump.txt for more details about crash dumps.
760 Don't change this unless you know what you are doing.
763 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
764 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
766 Say Y here to experiment with turning CPUs off and on, and to
767 enable suspend on SMP systems. CPUs can be controlled through
768 /sys/devices/system/cpu.
774 menu "Power management options (ACPI, APM)"
775 depends on !X86_VOYAGER
777 source kernel/power/Kconfig
779 source "drivers/acpi/Kconfig"
781 menu "APM (Advanced Power Management) BIOS Support"
782 depends on PM && !X86_VISWS
785 tristate "APM (Advanced Power Management) BIOS support"
788 APM is a BIOS specification for saving power using several different
789 techniques. This is mostly useful for battery powered laptops with
790 APM compliant BIOSes. If you say Y here, the system time will be
791 reset after a RESUME operation, the /proc/apm device will provide
792 battery status information, and user-space programs will receive
793 notification of APM "events" (e.g. battery status change).
795 If you select "Y" here, you can disable actual use of the APM
796 BIOS by passing the "apm=off" option to the kernel at boot time.
798 Note that the APM support is almost completely disabled for
799 machines with more than one CPU.
801 In order to use APM, you will need supporting software. For location
802 and more information, read <file:Documentation/pm.txt> and the
803 Battery Powered Linux mini-HOWTO, available from
804 <http://www.tldp.org/docs.html#howto>.
806 This driver does not spin down disk drives (see the hdparm(8)
807 manpage ("man 8 hdparm") for that), and it doesn't turn off
808 VESA-compliant "green" monitors.
810 This driver does not support the TI 4000M TravelMate and the ACER
811 486/DX4/75 because they don't have compliant BIOSes. Many "green"
812 desktop machines also don't have compliant BIOSes, and this driver
813 may cause those machines to panic during the boot phase.
815 Generally, if you don't have a battery in your machine, there isn't
816 much point in using this driver and you should say N. If you get
817 random kernel OOPSes or reboots that don't seem to be related to
818 anything, try disabling/enabling this option (or disabling/enabling
821 Some other things you should try when experiencing seemingly random,
824 1) make sure that you have enough swap space and that it is
826 2) pass the "no-hlt" option to the kernel
827 3) switch on floating point emulation in the kernel and pass
828 the "no387" option to the kernel
829 4) pass the "floppy=nodma" option to the kernel
830 5) pass the "mem=4M" option to the kernel (thereby disabling
831 all but the first 4 MB of RAM)
832 6) make sure that the CPU is not over clocked.
833 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
834 8) disable the cache from your BIOS settings
835 9) install a fan for the video card or exchange video RAM
836 10) install a better fan for the CPU
837 11) exchange RAM chips
838 12) exchange the motherboard.
840 To compile this driver as a module, choose M here: the
841 module will be called apm.
843 config APM_IGNORE_USER_SUSPEND
844 bool "Ignore USER SUSPEND"
847 This option will ignore USER SUSPEND requests. On machines with a
848 compliant APM BIOS, you want to say N. However, on the NEC Versa M
849 series notebooks, it is necessary to say Y because of a BIOS bug.
852 bool "Enable PM at boot time"
855 Enable APM features at boot time. From page 36 of the APM BIOS
856 specification: "When disabled, the APM BIOS does not automatically
857 power manage devices, enter the Standby State, enter the Suspend
858 State, or take power saving steps in response to CPU Idle calls."
859 This driver will make CPU Idle calls when Linux is idle (unless this
860 feature is turned off -- see "Do CPU IDLE calls", below). This
861 should always save battery power, but more complicated APM features
862 will be dependent on your BIOS implementation. You may need to turn
863 this option off if your computer hangs at boot time when using APM
864 support, or if it beeps continuously instead of suspending. Turn
865 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
866 T400CDT. This is off by default since most machines do fine without
870 bool "Make CPU Idle calls when idle"
873 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
874 On some machines, this can activate improved power savings, such as
875 a slowed CPU clock rate, when the machine is idle. These idle calls
876 are made after the idle loop has run for some length of time (e.g.,
877 333 mS). On some machines, this will cause a hang at boot time or
878 whenever the CPU becomes idle. (On machines with more than one CPU,
879 this option does nothing.)
881 config APM_DISPLAY_BLANK
882 bool "Enable console blanking using APM"
885 Enable console blanking using the APM. Some laptops can use this to
886 turn off the LCD backlight when the screen blanker of the Linux
887 virtual console blanks the screen. Note that this is only used by
888 the virtual console screen blanker, and won't turn off the backlight
889 when using the X Window system. This also doesn't have anything to
890 do with your VESA-compliant power-saving monitor. Further, this
891 option doesn't work for all laptops -- it might not turn off your
892 backlight at all, or it might print a lot of errors to the console,
893 especially if you are using gpm.
895 config APM_RTC_IS_GMT
896 bool "RTC stores time in GMT"
899 Say Y here if your RTC (Real Time Clock a.k.a. hardware clock)
900 stores the time in GMT (Greenwich Mean Time). Say N if your RTC
903 It is in fact recommended to store GMT in your RTC, because then you
904 don't have to worry about daylight savings time changes. The only
905 reason not to use GMT in your RTC is if you also run a broken OS
906 that doesn't understand GMT.
908 config APM_ALLOW_INTS
909 bool "Allow interrupts during APM BIOS calls"
912 Normally we disable external interrupts while we are making calls to
913 the APM BIOS as a measure to lessen the effects of a badly behaving
914 BIOS implementation. The BIOS should reenable interrupts if it
915 needs to. Unfortunately, some BIOSes do not -- especially those in
916 many of the newer IBM Thinkpads. If you experience hangs when you
917 suspend, try setting this to Y. Otherwise, say N.
919 config APM_REAL_MODE_POWER_OFF
920 bool "Use real mode APM BIOS call to power off"
923 Use real mode APM BIOS calls to switch off the computer. This is
924 a work-around for a number of buggy BIOSes. Switch this option on if
925 your computer crashes instead of powering off properly.
929 source "arch/i386/kernel/cpu/cpufreq/Kconfig"
933 menu "Bus options (PCI, PCMCIA, EISA, MCA, ISA)"
936 bool "PCI support" if !X86_VISWS
937 depends on !X86_VOYAGER
938 default y if X86_VISWS
940 Find out whether you have a PCI motherboard. PCI is the name of a
941 bus system, i.e. the way the CPU talks to the other stuff inside
942 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
943 VESA. If you have PCI, say Y, otherwise N.
945 The PCI-HOWTO, available from
946 <http://www.tldp.org/docs.html#howto>, contains valuable
947 information about which PCI hardware does work under Linux and which
951 prompt "PCI access mode"
952 depends on PCI && !X86_VISWS
955 On PCI systems, the BIOS can be used to detect the PCI devices and
956 determine their configuration. However, some old PCI motherboards
957 have BIOS bugs and may crash if this is done. Also, some embedded
958 PCI-based systems don't have any BIOS at all. Linux can also try to
959 detect the PCI hardware directly without using the BIOS.
961 With this option, you can specify how Linux should detect the
962 PCI devices. If you choose "BIOS", the BIOS will be used,
963 if you choose "Direct", the BIOS won't be used, and if you
964 choose "MMConfig", then PCI Express MMCONFIG will be used.
965 If you choose "Any", the kernel will try MMCONFIG, then the
966 direct access method and falls back to the BIOS if that doesn't
967 work. If unsure, go with the default, which is "Any".
972 config PCI_GOMMCONFIG
985 depends on !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
990 depends on PCI && ((PCI_GODIRECT || PCI_GOANY) || X86_VISWS)
995 depends on PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
998 source "drivers/pci/pcie/Kconfig"
1000 source "drivers/pci/Kconfig"
1008 depends on !(X86_VOYAGER || X86_VISWS)
1010 Find out whether you have ISA slots on your motherboard. ISA is the
1011 name of a bus system, i.e. the way the CPU talks to the other stuff
1012 inside your box. Other bus systems are PCI, EISA, MicroChannel
1013 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1014 newer boards don't support it. If you have ISA, say Y, otherwise N.
1020 The Extended Industry Standard Architecture (EISA) bus was
1021 developed as an open alternative to the IBM MicroChannel bus.
1023 The EISA bus provided some of the features of the IBM MicroChannel
1024 bus while maintaining backward compatibility with cards made for
1025 the older ISA bus. The EISA bus saw limited use between 1988 and
1026 1995 when it was made obsolete by the PCI bus.
1028 Say Y here if you are building a kernel for an EISA-based machine.
1032 source "drivers/eisa/Kconfig"
1035 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1036 default y if X86_VOYAGER
1038 MicroChannel Architecture is found in some IBM PS/2 machines and
1039 laptops. It is a bus system similar to PCI or ISA. See
1040 <file:Documentation/mca.txt> (and especially the web page given
1041 there) before attempting to build an MCA bus kernel.
1043 source "drivers/mca/Kconfig"
1046 tristate "NatSemi SCx200 support"
1047 depends on !X86_VOYAGER
1049 This provides basic support for the National Semiconductor SCx200
1050 processor. Right now this is just a driver for the GPIO pins.
1052 If you don't know what to do here, say N.
1054 This support is also available as a module. If compiled as a
1055 module, it will be called scx200.
1057 source "drivers/pcmcia/Kconfig"
1059 source "drivers/pci/hotplug/Kconfig"
1063 menu "Executable file formats"
1065 source "fs/Kconfig.binfmt"
1069 source "net/Kconfig"
1071 source "drivers/Kconfig"
1075 menu "Instrumentation Support"
1076 depends on EXPERIMENTAL
1078 source "arch/i386/oprofile/Kconfig"
1081 bool "Kprobes (EXPERIMENTAL)"
1082 depends on EXPERIMENTAL && MODULES
1084 Kprobes allows you to trap at almost any kernel address and
1085 execute a callback function. register_kprobe() establishes
1086 a probepoint and specifies the callback. Kprobes is useful
1087 for kernel debugging, non-intrusive instrumentation and testing.
1088 If in doubt, say "N".
1091 source "arch/i386/Kconfig.debug"
1093 source "security/Kconfig"
1095 source "crypto/Kconfig"
1097 source "lib/Kconfig"
1100 # Use the generic interrupt handling code in kernel/irq/:
1102 config GENERIC_HARDIRQS
1106 config GENERIC_IRQ_PROBE
1110 config GENERIC_PENDING_IRQ
1112 depends on GENERIC_HARDIRQS && SMP
1117 depends on SMP && !X86_VOYAGER
1122 depends on SMP && !(X86_VISWS || X86_VOYAGER)
1125 config X86_BIOS_REBOOT
1127 depends on !(X86_VISWS || X86_VOYAGER)
1130 config X86_TRAMPOLINE
1132 depends on X86_SMP || (X86_VOYAGER && SMP)
projects / linux-2.6 / blob