| blob | e0edaaa6920af63832979a04d4f525acafe64e8a |
1 # x86 configuration
2 mainmenu "Linux Kernel Configuration for x86"
4 # Select 32 or 64 bit
5 config 64BIT
6 bool "64-bit kernel" if ARCH = "x86"
7 default ARCH = "x86_64"
8 help
9 Say yes to build a 64-bit kernel - formerly known as x86_64
10 Say no to build a 32-bit kernel - formerly known as i386
12 config X86_32
13 def_bool !64BIT
15 config X86_64
16 def_bool 64BIT
18 ### Arch settings
19 config X86
20 def_bool y
21 select HAVE_UNSTABLE_SCHED_CLOCK
22 select HAVE_IDE
23 select HAVE_OPROFILE
24 select HAVE_KPROBES
25 select HAVE_KRETPROBES
26 select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64)
27 select HAVE_ARCH_KGDB if !X86_VOYAGER
29 config ARCH_DEFCONFIG
30 string
31 default "arch/x86/configs/i386_defconfig" if X86_32
32 default "arch/x86/configs/x86_64_defconfig" if X86_64
35 config GENERIC_LOCKBREAK
36 def_bool n
38 config GENERIC_TIME
39 def_bool y
41 config GENERIC_CMOS_UPDATE
42 def_bool y
44 config CLOCKSOURCE_WATCHDOG
45 def_bool y
47 config GENERIC_CLOCKEVENTS
48 def_bool y
50 config GENERIC_CLOCKEVENTS_BROADCAST
51 def_bool y
52 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
54 config LOCKDEP_SUPPORT
55 def_bool y
57 config STACKTRACE_SUPPORT
58 def_bool y
60 config HAVE_LATENCYTOP_SUPPORT
61 def_bool y
63 config FAST_CMPXCHG_LOCAL
64 bool
65 default y
67 config MMU
68 def_bool y
70 config ZONE_DMA
71 def_bool y
73 config SBUS
74 bool
76 config GENERIC_ISA_DMA
77 def_bool y
79 config GENERIC_IOMAP
80 def_bool y
82 config GENERIC_BUG
83 def_bool y
84 depends on BUG
86 config GENERIC_HWEIGHT
87 def_bool y
89 config GENERIC_GPIO
90 def_bool n
92 config ARCH_MAY_HAVE_PC_FDC
93 def_bool y
95 config RWSEM_GENERIC_SPINLOCK
96 def_bool !X86_XADD
98 config RWSEM_XCHGADD_ALGORITHM
99 def_bool X86_XADD
101 config ARCH_HAS_ILOG2_U32
102 def_bool n
104 config ARCH_HAS_ILOG2_U64
105 def_bool n
107 config ARCH_HAS_CPU_IDLE_WAIT
108 def_bool y
110 config GENERIC_CALIBRATE_DELAY
111 def_bool y
113 config GENERIC_TIME_VSYSCALL
114 bool
115 default X86_64
117 config ARCH_HAS_CPU_RELAX
118 def_bool y
120 config ARCH_HAS_CACHE_LINE_SIZE
121 def_bool y
123 config HAVE_SETUP_PER_CPU_AREA
124 def_bool X86_64 || (X86_SMP && !X86_VOYAGER)
126 config HAVE_CPUMASK_OF_CPU_MAP
127 def_bool X86_64_SMP
129 config ARCH_HIBERNATION_POSSIBLE
130 def_bool y
131 depends on !SMP || !X86_VOYAGER
133 config ARCH_SUSPEND_POSSIBLE
134 def_bool y
135 depends on !X86_VOYAGER
137 config ZONE_DMA32
138 bool
139 default X86_64
141 config ARCH_POPULATES_NODE_MAP
142 def_bool y
144 config AUDIT_ARCH
145 bool
146 default X86_64
148 config ARCH_SUPPORTS_AOUT
149 def_bool y
151 config ARCH_SUPPORTS_OPTIMIZED_INLINING
152 def_bool y
154 # Use the generic interrupt handling code in kernel/irq/:
155 config GENERIC_HARDIRQS
156 bool
157 default y
159 config GENERIC_IRQ_PROBE
160 bool
161 default y
163 config GENERIC_PENDING_IRQ
164 bool
165 depends on GENERIC_HARDIRQS && SMP
166 default y
168 config X86_SMP
169 bool
170 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64)
171 default y
173 config X86_32_SMP
174 def_bool y
175 depends on X86_32 && SMP
177 config X86_64_SMP
178 def_bool y
179 depends on X86_64 && SMP
181 config X86_HT
182 bool
183 depends on SMP
184 depends on (X86_32 && !(X86_VISWS || X86_VOYAGER)) || X86_64
185 default y
187 config X86_BIOS_REBOOT
188 bool
189 depends on !X86_VISWS && !X86_VOYAGER
190 default y
192 config X86_TRAMPOLINE
193 bool
194 depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP)
195 default y
197 config KTIME_SCALAR
198 def_bool X86_32
199 source "init/Kconfig"
201 menu "Processor type and features"
203 source "kernel/time/Kconfig"
205 config SMP
206 bool "Symmetric multi-processing support"
207 ---help---
208 This enables support for systems with more than one CPU. If you have
209 a system with only one CPU, like most personal computers, say N. If
210 you have a system with more than one CPU, say Y.
212 If you say N here, the kernel will run on single and multiprocessor
213 machines, but will use only one CPU of a multiprocessor machine. If
214 you say Y here, the kernel will run on many, but not all,
215 singleprocessor machines. On a singleprocessor machine, the kernel
216 will run faster if you say N here.
218 Note that if you say Y here and choose architecture "586" or
219 "Pentium" under "Processor family", the kernel will not work on 486
220 architectures. Similarly, multiprocessor kernels for the "PPro"
221 architecture may not work on all Pentium based boards.
223 People using multiprocessor machines who say Y here should also say
224 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
225 Management" code will be disabled if you say Y here.
227 See also <file:Documentation/i386/IO-APIC.txt>,
228 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
229 <http://www.tldp.org/docs.html#howto>.
231 If you don't know what to do here, say N.
233 choice
234 prompt "Subarchitecture Type"
235 default X86_PC
237 config X86_PC
238 bool "PC-compatible"
239 help
240 Choose this option if your computer is a standard PC or compatible.
242 config X86_ELAN
243 bool "AMD Elan"
244 depends on X86_32
245 help
246 Select this for an AMD Elan processor.
248 Do not use this option for K6/Athlon/Opteron processors!
250 If unsure, choose "PC-compatible" instead.
252 config X86_VOYAGER
253 bool "Voyager (NCR)"
254 depends on X86_32 && (SMP || BROKEN)
255 help
256 Voyager is an MCA-based 32-way capable SMP architecture proprietary
257 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
259 *** WARNING ***
261 If you do not specifically know you have a Voyager based machine,
262 say N here, otherwise the kernel you build will not be bootable.
264 config X86_NUMAQ
265 bool "NUMAQ (IBM/Sequent)"
266 depends on SMP && X86_32
267 select NUMA
268 help
269 This option is used for getting Linux to run on a (IBM/Sequent) NUMA
270 multiquad box. This changes the way that processors are bootstrapped,
271 and uses Clustered Logical APIC addressing mode instead of Flat Logical.
272 You will need a new lynxer.elf file to flash your firmware with - send
273 email to <Martin.Bligh@us.ibm.com>.
275 config X86_SUMMIT
276 bool "Summit/EXA (IBM x440)"
277 depends on X86_32 && SMP
278 help
279 This option is needed for IBM systems that use the Summit/EXA chipset.
280 In particular, it is needed for the x440.
282 If you don't have one of these computers, you should say N here.
283 If you want to build a NUMA kernel, you must select ACPI.
285 config X86_BIGSMP
286 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
287 depends on X86_32 && SMP
288 help
289 This option is needed for the systems that have more than 8 CPUs
290 and if the system is not of any sub-arch type above.
292 If you don't have such a system, you should say N here.
294 config X86_VISWS
295 bool "SGI 320/540 (Visual Workstation)"
296 depends on X86_32
297 help
298 The SGI Visual Workstation series is an IA32-based workstation
299 based on SGI systems chips with some legacy PC hardware attached.
301 Say Y here to create a kernel to run on the SGI 320 or 540.
303 A kernel compiled for the Visual Workstation will not run on PCs
304 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
306 config X86_GENERICARCH
307 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
308 depends on X86_32
309 help
310 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
311 It is intended for a generic binary kernel.
312 If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
314 config X86_ES7000
315 bool "Support for Unisys ES7000 IA32 series"
316 depends on X86_32 && SMP
317 help
318 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
319 supposed to run on an IA32-based Unisys ES7000 system.
320 Only choose this option if you have such a system, otherwise you
321 should say N here.
323 config X86_RDC321X
324 bool "RDC R-321x SoC"
325 depends on X86_32
326 select M486
327 select X86_REBOOTFIXUPS
328 select GENERIC_GPIO
329 select LEDS_CLASS
330 select LEDS_GPIO
331 select NEW_LEDS
332 help
333 This option is needed for RDC R-321x system-on-chip, also known
334 as R-8610-(G).
335 If you don't have one of these chips, you should say N here.
337 config X86_VSMP
338 bool "Support for ScaleMP vSMP"
339 select PARAVIRT
340 depends on X86_64
341 help
342 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
343 supposed to run on these EM64T-based machines. Only choose this option
344 if you have one of these machines.
346 endchoice
348 config SCHED_NO_NO_OMIT_FRAME_POINTER
349 def_bool y
350 prompt "Single-depth WCHAN output"
351 depends on X86_32
352 help
353 Calculate simpler /proc/<PID>/wchan values. If this option
354 is disabled then wchan values will recurse back to the
355 caller function. This provides more accurate wchan values,
356 at the expense of slightly more scheduling overhead.
358 If in doubt, say "Y".
360 menuconfig PARAVIRT_GUEST
361 bool "Paravirtualized guest support"
362 help
363 Say Y here to get to see options related to running Linux under
364 various hypervisors. This option alone does not add any kernel code.
366 If you say N, all options in this submenu will be skipped and disabled.
368 if PARAVIRT_GUEST
370 source "arch/x86/xen/Kconfig"
372 config VMI
373 bool "VMI Guest support"
374 select PARAVIRT
375 depends on X86_32
376 depends on !(X86_VISWS || X86_VOYAGER)
377 help
378 VMI provides a paravirtualized interface to the VMware ESX server
379 (it could be used by other hypervisors in theory too, but is not
380 at the moment), by linking the kernel to a GPL-ed ROM module
381 provided by the hypervisor.
383 config KVM_CLOCK
384 bool "KVM paravirtualized clock"
385 select PARAVIRT
386 select PARAVIRT_CLOCK
387 depends on !(X86_VISWS || X86_VOYAGER)
388 help
389 Turning on this option will allow you to run a paravirtualized clock
390 when running over the KVM hypervisor. Instead of relying on a PIT
391 (or probably other) emulation by the underlying device model, the host
392 provides the guest with timing infrastructure such as time of day, and
393 system time
395 config KVM_GUEST
396 bool "KVM Guest support"
397 select PARAVIRT
398 depends on !(X86_VISWS || X86_VOYAGER)
399 help
400 This option enables various optimizations for running under the KVM
401 hypervisor.
403 source "arch/x86/lguest/Kconfig"
405 config PARAVIRT
406 bool "Enable paravirtualization code"
407 depends on !(X86_VISWS || X86_VOYAGER)
408 help
409 This changes the kernel so it can modify itself when it is run
410 under a hypervisor, potentially improving performance significantly
411 over full virtualization. However, when run without a hypervisor
412 the kernel is theoretically slower and slightly larger.
414 config PARAVIRT_CLOCK
415 bool
416 default n
418 endif
420 config MEMTEST_BOOTPARAM
421 bool "Memtest boot parameter"
422 depends on X86_64
423 default y
424 help
425 This option adds a kernel parameter 'memtest', which allows memtest
426 to be disabled at boot. If this option is selected, memtest
427 functionality can be disabled with memtest=0 on the kernel
428 command line. The purpose of this option is to allow a single
429 kernel image to be distributed with memtest built in, but not
430 necessarily enabled.
432 If you are unsure how to answer this question, answer Y.
434 config MEMTEST_BOOTPARAM_VALUE
435 int "Memtest boot parameter default value (0-4)"
436 depends on MEMTEST_BOOTPARAM
437 range 0 4
438 default 0
439 help
440 This option sets the default value for the kernel parameter
441 'memtest', which allows memtest to be disabled at boot. If this
442 option is set to 0 (zero), the memtest kernel parameter will
443 default to 0, disabling memtest at bootup. If this option is
444 set to 4, the memtest kernel parameter will default to 4,
445 enabling memtest at bootup, and use that as pattern number.
447 If you are unsure how to answer this question, answer 0.
449 config ACPI_SRAT
450 def_bool y
451 depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
452 select ACPI_NUMA
454 config HAVE_ARCH_PARSE_SRAT
455 def_bool y
456 depends on ACPI_SRAT
458 config X86_SUMMIT_NUMA
459 def_bool y
460 depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH)
462 config X86_CYCLONE_TIMER
463 def_bool y
464 depends on X86_32 && X86_SUMMIT || X86_GENERICARCH
466 config ES7000_CLUSTERED_APIC
467 def_bool y
468 depends on SMP && X86_ES7000 && MPENTIUMIII
470 source "arch/x86/Kconfig.cpu"
472 config HPET_TIMER
473 def_bool X86_64
474 prompt "HPET Timer Support" if X86_32
475 help
476 Use the IA-PC HPET (High Precision Event Timer) to manage
477 time in preference to the PIT and RTC, if a HPET is
478 present.
479 HPET is the next generation timer replacing legacy 8254s.
480 The HPET provides a stable time base on SMP
481 systems, unlike the TSC, but it is more expensive to access,
482 as it is off-chip. You can find the HPET spec at
483 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
485 You can safely choose Y here. However, HPET will only be
486 activated if the platform and the BIOS support this feature.
487 Otherwise the 8254 will be used for timing services.
489 Choose N to continue using the legacy 8254 timer.
491 config HPET_EMULATE_RTC
492 def_bool y
493 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
495 # Mark as embedded because too many people got it wrong.
496 # The code disables itself when not needed.
497 config DMI
498 default y
499 bool "Enable DMI scanning" if EMBEDDED
500 help
501 Enabled scanning of DMI to identify machine quirks. Say Y
502 here unless you have verified that your setup is not
503 affected by entries in the DMI blacklist. Required by PNP
504 BIOS code.
506 config GART_IOMMU
507 bool "GART IOMMU support" if EMBEDDED
508 default y
509 select SWIOTLB
510 select AGP
511 depends on X86_64 && PCI
512 help
513 Support for full DMA access of devices with 32bit memory access only
514 on systems with more than 3GB. This is usually needed for USB,
515 sound, many IDE/SATA chipsets and some other devices.
516 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
517 based hardware IOMMU and a software bounce buffer based IOMMU used
518 on Intel systems and as fallback.
519 The code is only active when needed (enough memory and limited
520 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
521 too.
523 config CALGARY_IOMMU
524 bool "IBM Calgary IOMMU support"
525 select SWIOTLB
526 depends on X86_64 && PCI && EXPERIMENTAL
527 help
528 Support for hardware IOMMUs in IBM's xSeries x366 and x460
529 systems. Needed to run systems with more than 3GB of memory
530 properly with 32-bit PCI devices that do not support DAC
531 (Double Address Cycle). Calgary also supports bus level
532 isolation, where all DMAs pass through the IOMMU. This
533 prevents them from going anywhere except their intended
534 destination. This catches hard-to-find kernel bugs and
535 mis-behaving drivers and devices that do not use the DMA-API
536 properly to set up their DMA buffers. The IOMMU can be
537 turned off at boot time with the iommu=off parameter.
538 Normally the kernel will make the right choice by itself.
539 If unsure, say Y.
541 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
542 def_bool y
543 prompt "Should Calgary be enabled by default?"
544 depends on CALGARY_IOMMU
545 help
546 Should Calgary be enabled by default? if you choose 'y', Calgary
547 will be used (if it exists). If you choose 'n', Calgary will not be
548 used even if it exists. If you choose 'n' and would like to use
549 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
550 If unsure, say Y.
552 # need this always selected by IOMMU for the VIA workaround
553 config SWIOTLB
554 bool
555 help
556 Support for software bounce buffers used on x86-64 systems
557 which don't have a hardware IOMMU (e.g. the current generation
558 of Intel's x86-64 CPUs). Using this PCI devices which can only
559 access 32-bits of memory can be used on systems with more than
560 3 GB of memory. If unsure, say Y.
562 config IOMMU_HELPER
563 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB)
565 config NR_CPUS
566 int "Maximum number of CPUs (2-255)"
567 range 2 255
568 depends on SMP
569 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
570 default "8"
571 help
572 This allows you to specify the maximum number of CPUs which this
573 kernel will support. The maximum supported value is 255 and the
574 minimum value which makes sense is 2.
576 This is purely to save memory - each supported CPU adds
577 approximately eight kilobytes to the kernel image.
579 config SCHED_SMT
580 bool "SMT (Hyperthreading) scheduler support"
581 depends on X86_HT
582 help
583 SMT scheduler support improves the CPU scheduler's decision making
584 when dealing with Intel Pentium 4 chips with HyperThreading at a
585 cost of slightly increased overhead in some places. If unsure say
586 N here.
588 config SCHED_MC
589 def_bool y
590 prompt "Multi-core scheduler support"
591 depends on X86_HT
592 help
593 Multi-core scheduler support improves the CPU scheduler's decision
594 making when dealing with multi-core CPU chips at a cost of slightly
595 increased overhead in some places. If unsure say N here.
597 source "kernel/Kconfig.preempt"
599 config X86_UP_APIC
600 bool "Local APIC support on uniprocessors"
601 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
602 help
603 A local APIC (Advanced Programmable Interrupt Controller) is an
604 integrated interrupt controller in the CPU. If you have a single-CPU
605 system which has a processor with a local APIC, you can say Y here to
606 enable and use it. If you say Y here even though your machine doesn't
607 have a local APIC, then the kernel will still run with no slowdown at
608 all. The local APIC supports CPU-generated self-interrupts (timer,
609 performance counters), and the NMI watchdog which detects hard
610 lockups.
612 config X86_UP_IOAPIC
613 bool "IO-APIC support on uniprocessors"
614 depends on X86_UP_APIC
615 help
616 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
617 SMP-capable replacement for PC-style interrupt controllers. Most
618 SMP systems and many recent uniprocessor systems have one.
620 If you have a single-CPU system with an IO-APIC, you can say Y here
621 to use it. If you say Y here even though your machine doesn't have
622 an IO-APIC, then the kernel will still run with no slowdown at all.
624 config X86_LOCAL_APIC
625 def_bool y
626 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH))
628 config X86_IO_APIC
629 def_bool y
630 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH))
632 config X86_VISWS_APIC
633 def_bool y
634 depends on X86_32 && X86_VISWS
636 config X86_MCE
637 bool "Machine Check Exception"
638 depends on !X86_VOYAGER
639 ---help---
640 Machine Check Exception support allows the processor to notify the
641 kernel if it detects a problem (e.g. overheating, component failure).
642 The action the kernel takes depends on the severity of the problem,
643 ranging from a warning message on the console, to halting the machine.
644 Your processor must be a Pentium or newer to support this - check the
645 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
646 have a design flaw which leads to false MCE events - hence MCE is
647 disabled on all P5 processors, unless explicitly enabled with "mce"
648 as a boot argument. Similarly, if MCE is built in and creates a
649 problem on some new non-standard machine, you can boot with "nomce"
650 to disable it. MCE support simply ignores non-MCE processors like
651 the 386 and 486, so nearly everyone can say Y here.
653 config X86_MCE_INTEL
654 def_bool y
655 prompt "Intel MCE features"
656 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
657 help
658 Additional support for intel specific MCE features such as
659 the thermal monitor.
661 config X86_MCE_AMD
662 def_bool y
663 prompt "AMD MCE features"
664 depends on X86_64 && X86_MCE && X86_LOCAL_APIC
665 help
666 Additional support for AMD specific MCE features such as
667 the DRAM Error Threshold.
669 config X86_MCE_NONFATAL
670 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
671 depends on X86_32 && X86_MCE
672 help
673 Enabling this feature starts a timer that triggers every 5 seconds which
674 will look at the machine check registers to see if anything happened.
675 Non-fatal problems automatically get corrected (but still logged).
676 Disable this if you don't want to see these messages.
677 Seeing the messages this option prints out may be indicative of dying
678 or out-of-spec (ie, overclocked) hardware.
679 This option only does something on certain CPUs.
680 (AMD Athlon/Duron and Intel Pentium 4)
682 config X86_MCE_P4THERMAL
683 bool "check for P4 thermal throttling interrupt."
684 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
685 help
686 Enabling this feature will cause a message to be printed when the P4
687 enters thermal throttling.
689 config VM86
690 bool "Enable VM86 support" if EMBEDDED
691 default y
692 depends on X86_32
693 help
694 This option is required by programs like DOSEMU to run 16-bit legacy
695 code on X86 processors. It also may be needed by software like
696 XFree86 to initialize some video cards via BIOS. Disabling this
697 option saves about 6k.
699 config TOSHIBA
700 tristate "Toshiba Laptop support"
701 depends on X86_32
702 ---help---
703 This adds a driver to safely access the System Management Mode of
704 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
705 not work on models with a Phoenix BIOS. The System Management Mode
706 is used to set the BIOS and power saving options on Toshiba portables.
708 For information on utilities to make use of this driver see the
709 Toshiba Linux utilities web site at:
710 <http://www.buzzard.org.uk/toshiba/>.
712 Say Y if you intend to run this kernel on a Toshiba portable.
713 Say N otherwise.
715 config I8K
716 tristate "Dell laptop support"
717 ---help---
718 This adds a driver to safely access the System Management Mode
719 of the CPU on the Dell Inspiron 8000. The System Management Mode
720 is used to read cpu temperature and cooling fan status and to
721 control the fans on the I8K portables.
723 This driver has been tested only on the Inspiron 8000 but it may
724 also work with other Dell laptops. You can force loading on other
725 models by passing the parameter `force=1' to the module. Use at
726 your own risk.
728 For information on utilities to make use of this driver see the
729 I8K Linux utilities web site at:
730 <http://people.debian.org/~dz/i8k/>
732 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
733 Say N otherwise.
735 config X86_REBOOTFIXUPS
736 def_bool n
737 prompt "Enable X86 board specific fixups for reboot"
738 depends on X86_32 && X86
739 ---help---
740 This enables chipset and/or board specific fixups to be done
741 in order to get reboot to work correctly. This is only needed on
742 some combinations of hardware and BIOS. The symptom, for which
743 this config is intended, is when reboot ends with a stalled/hung
744 system.
746 Currently, the only fixup is for the Geode machines using
747 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
749 Say Y if you want to enable the fixup. Currently, it's safe to
750 enable this option even if you don't need it.
751 Say N otherwise.
753 config MICROCODE
754 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
755 select FW_LOADER
756 ---help---
757 If you say Y here, you will be able to update the microcode on
758 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
759 Pentium III, Pentium 4, Xeon etc. You will obviously need the
760 actual microcode binary data itself which is not shipped with the
761 Linux kernel.
763 For latest news and information on obtaining all the required
764 ingredients for this driver, check:
765 <http://www.urbanmyth.org/microcode/>.
767 To compile this driver as a module, choose M here: the
768 module will be called microcode.
770 config MICROCODE_OLD_INTERFACE
771 def_bool y
772 depends on MICROCODE
774 config X86_MSR
775 tristate "/dev/cpu/*/msr - Model-specific register support"
776 help
777 This device gives privileged processes access to the x86
778 Model-Specific Registers (MSRs). It is a character device with
779 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
780 MSR accesses are directed to a specific CPU on multi-processor
781 systems.
783 config X86_CPUID
784 tristate "/dev/cpu/*/cpuid - CPU information support"
785 help
786 This device gives processes access to the x86 CPUID instruction to
787 be executed on a specific processor. It is a character device
788 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
789 /dev/cpu/31/cpuid.
791 choice
792 prompt "High Memory Support"
793 default HIGHMEM4G if !X86_NUMAQ
794 default HIGHMEM64G if X86_NUMAQ
795 depends on X86_32
797 config NOHIGHMEM
798 bool "off"
799 depends on !X86_NUMAQ
800 ---help---
801 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
802 However, the address space of 32-bit x86 processors is only 4
803 Gigabytes large. That means that, if you have a large amount of
804 physical memory, not all of it can be "permanently mapped" by the
805 kernel. The physical memory that's not permanently mapped is called
806 "high memory".
808 If you are compiling a kernel which will never run on a machine with
809 more than 1 Gigabyte total physical RAM, answer "off" here (default
810 choice and suitable for most users). This will result in a "3GB/1GB"
811 split: 3GB are mapped so that each process sees a 3GB virtual memory
812 space and the remaining part of the 4GB virtual memory space is used
813 by the kernel to permanently map as much physical memory as
814 possible.
816 If the machine has between 1 and 4 Gigabytes physical RAM, then
817 answer "4GB" here.
819 If more than 4 Gigabytes is used then answer "64GB" here. This
820 selection turns Intel PAE (Physical Address Extension) mode on.
821 PAE implements 3-level paging on IA32 processors. PAE is fully
822 supported by Linux, PAE mode is implemented on all recent Intel
823 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
824 then the kernel will not boot on CPUs that don't support PAE!
826 The actual amount of total physical memory will either be
827 auto detected or can be forced by using a kernel command line option
828 such as "mem=256M". (Try "man bootparam" or see the documentation of
829 your boot loader (lilo or loadlin) about how to pass options to the
830 kernel at boot time.)
832 If unsure, say "off".
834 config HIGHMEM4G
835 bool "4GB"
836 depends on !X86_NUMAQ
837 help
838 Select this if you have a 32-bit processor and between 1 and 4
839 gigabytes of physical RAM.
841 config HIGHMEM64G
842 bool "64GB"
843 depends on !M386 && !M486
844 select X86_PAE
845 help
846 Select this if you have a 32-bit processor and more than 4
847 gigabytes of physical RAM.
849 endchoice
851 choice
852 depends on EXPERIMENTAL
853 prompt "Memory split" if EMBEDDED
854 default VMSPLIT_3G
855 depends on X86_32
856 help
857 Select the desired split between kernel and user memory.
859 If the address range available to the kernel is less than the
860 physical memory installed, the remaining memory will be available
861 as "high memory". Accessing high memory is a little more costly
862 than low memory, as it needs to be mapped into the kernel first.
863 Note that increasing the kernel address space limits the range
864 available to user programs, making the address space there
865 tighter. Selecting anything other than the default 3G/1G split
866 will also likely make your kernel incompatible with binary-only
867 kernel modules.
869 If you are not absolutely sure what you are doing, leave this
870 option alone!
872 config VMSPLIT_3G
873 bool "3G/1G user/kernel split"
874 config VMSPLIT_3G_OPT
875 depends on !X86_PAE
876 bool "3G/1G user/kernel split (for full 1G low memory)"
877 config VMSPLIT_2G
878 bool "2G/2G user/kernel split"
879 config VMSPLIT_2G_OPT
880 depends on !X86_PAE
881 bool "2G/2G user/kernel split (for full 2G low memory)"
882 config VMSPLIT_1G
883 bool "1G/3G user/kernel split"
884 endchoice
886 config PAGE_OFFSET
887 hex
888 default 0xB0000000 if VMSPLIT_3G_OPT
889 default 0x80000000 if VMSPLIT_2G
890 default 0x78000000 if VMSPLIT_2G_OPT
891 default 0x40000000 if VMSPLIT_1G
892 default 0xC0000000
893 depends on X86_32
895 config HIGHMEM
896 def_bool y
897 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
899 config X86_PAE
900 def_bool n
901 prompt "PAE (Physical Address Extension) Support"
902 depends on X86_32 && !HIGHMEM4G
903 select RESOURCES_64BIT
904 help
905 PAE is required for NX support, and furthermore enables
906 larger swapspace support for non-overcommit purposes. It
907 has the cost of more pagetable lookup overhead, and also
908 consumes more pagetable space per process.
910 # Common NUMA Features
911 config NUMA
912 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)"
913 depends on SMP
914 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL)
915 default n if X86_PC
916 default y if (X86_NUMAQ || X86_SUMMIT)
917 help
918 Enable NUMA (Non Uniform Memory Access) support.
919 The kernel will try to allocate memory used by a CPU on the
920 local memory controller of the CPU and add some more
921 NUMA awareness to the kernel.
923 For i386 this is currently highly experimental and should be only
924 used for kernel development. It might also cause boot failures.
925 For x86_64 this is recommended on all multiprocessor Opteron systems.
926 If the system is EM64T, you should say N unless your system is
927 EM64T NUMA.
929 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
930 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
932 config K8_NUMA
933 def_bool y
934 prompt "Old style AMD Opteron NUMA detection"
935 depends on X86_64 && NUMA && PCI
936 help
937 Enable K8 NUMA node topology detection. You should say Y here if
938 you have a multi processor AMD K8 system. This uses an old
939 method to read the NUMA configuration directly from the builtin
940 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
941 instead, which also takes priority if both are compiled in.
943 config X86_64_ACPI_NUMA
944 def_bool y
945 prompt "ACPI NUMA detection"
946 depends on X86_64 && NUMA && ACPI && PCI
947 select ACPI_NUMA
948 help
949 Enable ACPI SRAT based node topology detection.
951 # Some NUMA nodes have memory ranges that span
952 # other nodes. Even though a pfn is valid and
953 # between a node's start and end pfns, it may not
954 # reside on that node. See memmap_init_zone()
955 # for details.
956 config NODES_SPAN_OTHER_NODES
957 def_bool y
958 depends on X86_64_ACPI_NUMA
960 config NUMA_EMU
961 bool "NUMA emulation"
962 depends on X86_64 && NUMA
963 help
964 Enable NUMA emulation. A flat machine will be split
965 into virtual nodes when booted with "numa=fake=N", where N is the
966 number of nodes. This is only useful for debugging.
968 config NODES_SHIFT
969 int "Max num nodes shift(1-15)"
970 range 1 15 if X86_64
971 default "6" if X86_64
972 default "4" if X86_NUMAQ
973 default "3"
974 depends on NEED_MULTIPLE_NODES
976 config HAVE_ARCH_BOOTMEM_NODE
977 def_bool y
978 depends on X86_32 && NUMA
980 config ARCH_HAVE_MEMORY_PRESENT
981 def_bool y
982 depends on X86_32 && DISCONTIGMEM
984 config NEED_NODE_MEMMAP_SIZE
985 def_bool y
986 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
988 config HAVE_ARCH_ALLOC_REMAP
989 def_bool y
990 depends on X86_32 && NUMA
992 config ARCH_FLATMEM_ENABLE
993 def_bool y
994 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA
996 config ARCH_DISCONTIGMEM_ENABLE
997 def_bool y
998 depends on NUMA && X86_32
1000 config ARCH_DISCONTIGMEM_DEFAULT
1001 def_bool y
1002 depends on NUMA && X86_32
1004 config ARCH_SPARSEMEM_DEFAULT
1005 def_bool y
1006 depends on X86_64
1008 config ARCH_SPARSEMEM_ENABLE
1009 def_bool y
1010 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC)
1011 select SPARSEMEM_STATIC if X86_32
1012 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1014 config ARCH_SELECT_MEMORY_MODEL
1015 def_bool y
1016 depends on ARCH_SPARSEMEM_ENABLE
1018 config ARCH_MEMORY_PROBE
1019 def_bool X86_64
1020 depends on MEMORY_HOTPLUG
1022 source "mm/Kconfig"
1024 config HIGHPTE
1025 bool "Allocate 3rd-level pagetables from highmem"
1026 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1027 help
1028 The VM uses one page table entry for each page of physical memory.
1029 For systems with a lot of RAM, this can be wasteful of precious
1030 low memory. Setting this option will put user-space page table
1031 entries in high memory.
1033 config MATH_EMULATION
1034 bool
1035 prompt "Math emulation" if X86_32
1036 ---help---
1037 Linux can emulate a math coprocessor (used for floating point
1038 operations) if you don't have one. 486DX and Pentium processors have
1039 a math coprocessor built in, 486SX and 386 do not, unless you added
1040 a 487DX or 387, respectively. (The messages during boot time can
1041 give you some hints here ["man dmesg"].) Everyone needs either a
1042 coprocessor or this emulation.
1044 If you don't have a math coprocessor, you need to say Y here; if you
1045 say Y here even though you have a coprocessor, the coprocessor will
1046 be used nevertheless. (This behavior can be changed with the kernel
1047 command line option "no387", which comes handy if your coprocessor
1048 is broken. Try "man bootparam" or see the documentation of your boot
1049 loader (lilo or loadlin) about how to pass options to the kernel at
1050 boot time.) This means that it is a good idea to say Y here if you
1051 intend to use this kernel on different machines.
1053 More information about the internals of the Linux math coprocessor
1054 emulation can be found in <file:arch/x86/math-emu/README>.
1056 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1057 kernel, it won't hurt.
1059 config MTRR
1060 bool "MTRR (Memory Type Range Register) support"
1061 ---help---
1062 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1063 the Memory Type Range Registers (MTRRs) may be used to control
1064 processor access to memory ranges. This is most useful if you have
1065 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1066 allows bus write transfers to be combined into a larger transfer
1067 before bursting over the PCI/AGP bus. This can increase performance
1068 of image write operations 2.5 times or more. Saying Y here creates a
1069 /proc/mtrr file which may be used to manipulate your processor's
1070 MTRRs. Typically the X server should use this.
1072 This code has a reasonably generic interface so that similar
1073 control registers on other processors can be easily supported
1074 as well:
1076 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1077 Registers (ARRs) which provide a similar functionality to MTRRs. For
1078 these, the ARRs are used to emulate the MTRRs.
1079 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1080 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1081 write-combining. All of these processors are supported by this code
1082 and it makes sense to say Y here if you have one of them.
1084 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1085 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1086 can lead to all sorts of problems, so it's good to say Y here.
1088 You can safely say Y even if your machine doesn't have MTRRs, you'll
1089 just add about 9 KB to your kernel.
1091 See <file:Documentation/mtrr.txt> for more information.
1093 config X86_PAT
1094 bool
1095 prompt "x86 PAT support"
1096 depends on MTRR
1097 help
1098 Use PAT attributes to setup page level cache control.
1100 PATs are the modern equivalents of MTRRs and are much more
1101 flexible than MTRRs.
1103 Say N here if you see bootup problems (boot crash, boot hang,
1104 spontaneous reboots) or a non-working video driver.
1106 If unsure, say Y.
1108 config EFI
1109 def_bool n
1110 prompt "EFI runtime service support"
1111 depends on ACPI
1112 ---help---
1113 This enables the kernel to use EFI runtime services that are
1114 available (such as the EFI variable services).
1116 This option is only useful on systems that have EFI firmware.
1117 In addition, you should use the latest ELILO loader available
1118 at <http://elilo.sourceforge.net> in order to take advantage
1119 of EFI runtime services. However, even with this option, the
1120 resultant kernel should continue to boot on existing non-EFI
1121 platforms.
1123 config IRQBALANCE
1124 def_bool y
1125 prompt "Enable kernel irq balancing"
1126 depends on X86_32 && SMP && X86_IO_APIC
1127 help
1128 The default yes will allow the kernel to do irq load balancing.
1129 Saying no will keep the kernel from doing irq load balancing.
1131 config SECCOMP
1132 def_bool y
1133 prompt "Enable seccomp to safely compute untrusted bytecode"
1134 depends on PROC_FS
1135 help
1136 This kernel feature is useful for number crunching applications
1137 that may need to compute untrusted bytecode during their
1138 execution. By using pipes or other transports made available to
1139 the process as file descriptors supporting the read/write
1140 syscalls, it's possible to isolate those applications in
1141 their own address space using seccomp. Once seccomp is
1142 enabled via /proc/<pid>/seccomp, it cannot be disabled
1143 and the task is only allowed to execute a few safe syscalls
1144 defined by each seccomp mode.
1146 If unsure, say Y. Only embedded should say N here.
1148 config CC_STACKPROTECTOR
1149 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1150 depends on X86_64 && EXPERIMENTAL && BROKEN
1151 help
1152 This option turns on the -fstack-protector GCC feature. This
1153 feature puts, at the beginning of critical functions, a canary
1154 value on the stack just before the return address, and validates
1155 the value just before actually returning. Stack based buffer
1156 overflows (that need to overwrite this return address) now also
1157 overwrite the canary, which gets detected and the attack is then
1158 neutralized via a kernel panic.
1160 This feature requires gcc version 4.2 or above, or a distribution
1161 gcc with the feature backported. Older versions are automatically
1162 detected and for those versions, this configuration option is ignored.
1164 config CC_STACKPROTECTOR_ALL
1165 bool "Use stack-protector for all functions"
1166 depends on CC_STACKPROTECTOR
1167 help
1168 Normally, GCC only inserts the canary value protection for
1169 functions that use large-ish on-stack buffers. By enabling
1170 this option, GCC will be asked to do this for ALL functions.
1172 source kernel/Kconfig.hz
1174 config KEXEC
1175 bool "kexec system call"
1176 depends on X86_BIOS_REBOOT
1177 help
1178 kexec is a system call that implements the ability to shutdown your
1179 current kernel, and to start another kernel. It is like a reboot
1180 but it is independent of the system firmware. And like a reboot
1181 you can start any kernel with it, not just Linux.
1183 The name comes from the similarity to the exec system call.
1185 It is an ongoing process to be certain the hardware in a machine
1186 is properly shutdown, so do not be surprised if this code does not
1187 initially work for you. It may help to enable device hotplugging
1188 support. As of this writing the exact hardware interface is
1189 strongly in flux, so no good recommendation can be made.
1191 config CRASH_DUMP
1192 bool "kernel crash dumps (EXPERIMENTAL)"
1193 depends on EXPERIMENTAL
1194 depends on X86_64 || (X86_32 && HIGHMEM)
1195 help
1196 Generate crash dump after being started by kexec.
1197 This should be normally only set in special crash dump kernels
1198 which are loaded in the main kernel with kexec-tools into
1199 a specially reserved region and then later executed after
1200 a crash by kdump/kexec. The crash dump kernel must be compiled
1201 to a memory address not used by the main kernel or BIOS using
1202 PHYSICAL_START, or it must be built as a relocatable image
1203 (CONFIG_RELOCATABLE=y).
1204 For more details see Documentation/kdump/kdump.txt
1206 config PHYSICAL_START
1207 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1208 default "0x1000000" if X86_NUMAQ
1209 default "0x200000" if X86_64
1210 default "0x100000"
1211 help
1212 This gives the physical address where the kernel is loaded.
1214 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1215 bzImage will decompress itself to above physical address and
1216 run from there. Otherwise, bzImage will run from the address where
1217 it has been loaded by the boot loader and will ignore above physical
1218 address.
1220 In normal kdump cases one does not have to set/change this option
1221 as now bzImage can be compiled as a completely relocatable image
1222 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1223 address. This option is mainly useful for the folks who don't want
1224 to use a bzImage for capturing the crash dump and want to use a
1225 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1226 to be specifically compiled to run from a specific memory area
1227 (normally a reserved region) and this option comes handy.
1229 So if you are using bzImage for capturing the crash dump, leave
1230 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y.
1231 Otherwise if you plan to use vmlinux for capturing the crash dump
1232 change this value to start of the reserved region (Typically 16MB
1233 0x1000000). In other words, it can be set based on the "X" value as
1234 specified in the "crashkernel=YM@XM" command line boot parameter
1235 passed to the panic-ed kernel. Typically this parameter is set as
1236 crashkernel=64M@16M. Please take a look at
1237 Documentation/kdump/kdump.txt for more details about crash dumps.
1239 Usage of bzImage for capturing the crash dump is recommended as
1240 one does not have to build two kernels. Same kernel can be used
1241 as production kernel and capture kernel. Above option should have
1242 gone away after relocatable bzImage support is introduced. But it
1243 is present because there are users out there who continue to use
1244 vmlinux for dump capture. This option should go away down the
1245 line.
1247 Don't change this unless you know what you are doing.
1249 config RELOCATABLE
1250 bool "Build a relocatable kernel (EXPERIMENTAL)"
1251 depends on EXPERIMENTAL
1252 help
1253 This builds a kernel image that retains relocation information
1254 so it can be loaded someplace besides the default 1MB.
1255 The relocations tend to make the kernel binary about 10% larger,
1256 but are discarded at runtime.
1258 One use is for the kexec on panic case where the recovery kernel
1259 must live at a different physical address than the primary
1260 kernel.
1262 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1263 it has been loaded at and the compile time physical address
1264 (CONFIG_PHYSICAL_START) is ignored.
1266 config PHYSICAL_ALIGN
1267 hex
1268 prompt "Alignment value to which kernel should be aligned" if X86_32
1269 default "0x100000" if X86_32
1270 default "0x200000" if X86_64
1271 range 0x2000 0x400000
1272 help
1273 This value puts the alignment restrictions on physical address
1274 where kernel is loaded and run from. Kernel is compiled for an
1275 address which meets above alignment restriction.
1277 If bootloader loads the kernel at a non-aligned address and
1278 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1279 address aligned to above value and run from there.
1281 If bootloader loads the kernel at a non-aligned address and
1282 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1283 load address and decompress itself to the address it has been
1284 compiled for and run from there. The address for which kernel is
1285 compiled already meets above alignment restrictions. Hence the
1286 end result is that kernel runs from a physical address meeting
1287 above alignment restrictions.
1289 Don't change this unless you know what you are doing.
1291 config HOTPLUG_CPU
1292 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)"
1293 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
1294 ---help---
1295 Say Y here to experiment with turning CPUs off and on, and to
1296 enable suspend on SMP systems. CPUs can be controlled through
1297 /sys/devices/system/cpu.
1298 Say N if you want to disable CPU hotplug and don't need to
1299 suspend.
1301 config COMPAT_VDSO
1302 def_bool y
1303 prompt "Compat VDSO support"
1304 depends on X86_32 || IA32_EMULATION
1305 help
1306 Map the 32-bit VDSO to the predictable old-style address too.
1307 ---help---
1308 Say N here if you are running a sufficiently recent glibc
1309 version (2.3.3 or later), to remove the high-mapped
1310 VDSO mapping and to exclusively use the randomized VDSO.
1312 If unsure, say Y.
1314 endmenu
1316 config ARCH_ENABLE_MEMORY_HOTPLUG
1317 def_bool y
1318 depends on X86_64 || (X86_32 && HIGHMEM)
1320 config HAVE_ARCH_EARLY_PFN_TO_NID
1321 def_bool X86_64
1322 depends on NUMA
1324 menu "Power management options"
1325 depends on !X86_VOYAGER
1327 config ARCH_HIBERNATION_HEADER
1328 def_bool y
1329 depends on X86_64 && HIBERNATION
1331 source "kernel/power/Kconfig"
1333 source "drivers/acpi/Kconfig"
1335 config X86_APM_BOOT
1336 bool
1337 default y
1338 depends on APM || APM_MODULE
1340 menuconfig APM
1341 tristate "APM (Advanced Power Management) BIOS support"
1342 depends on X86_32 && PM_SLEEP && !X86_VISWS
1343 ---help---
1344 APM is a BIOS specification for saving power using several different
1345 techniques. This is mostly useful for battery powered laptops with
1346 APM compliant BIOSes. If you say Y here, the system time will be
1347 reset after a RESUME operation, the /proc/apm device will provide
1348 battery status information, and user-space programs will receive
1349 notification of APM "events" (e.g. battery status change).
1351 If you select "Y" here, you can disable actual use of the APM
1352 BIOS by passing the "apm=off" option to the kernel at boot time.
1354 Note that the APM support is almost completely disabled for
1355 machines with more than one CPU.
1357 In order to use APM, you will need supporting software. For location
1358 and more information, read <file:Documentation/power/pm.txt> and the
1359 Battery Powered Linux mini-HOWTO, available from
1360 <http://www.tldp.org/docs.html#howto>.
1362 This driver does not spin down disk drives (see the hdparm(8)
1363 manpage ("man 8 hdparm") for that), and it doesn't turn off
1364 VESA-compliant "green" monitors.
1366 This driver does not support the TI 4000M TravelMate and the ACER
1367 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1368 desktop machines also don't have compliant BIOSes, and this driver
1369 may cause those machines to panic during the boot phase.
1371 Generally, if you don't have a battery in your machine, there isn't
1372 much point in using this driver and you should say N. If you get
1373 random kernel OOPSes or reboots that don't seem to be related to
1374 anything, try disabling/enabling this option (or disabling/enabling
1375 APM in your BIOS).
1377 Some other things you should try when experiencing seemingly random,
1378 "weird" problems:
1380 1) make sure that you have enough swap space and that it is
1381 enabled.
1382 2) pass the "no-hlt" option to the kernel
1383 3) switch on floating point emulation in the kernel and pass
1384 the "no387" option to the kernel
1385 4) pass the "floppy=nodma" option to the kernel
1386 5) pass the "mem=4M" option to the kernel (thereby disabling
1387 all but the first 4 MB of RAM)
1388 6) make sure that the CPU is not over clocked.
1389 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1390 8) disable the cache from your BIOS settings
1391 9) install a fan for the video card or exchange video RAM
1392 10) install a better fan for the CPU
1393 11) exchange RAM chips
1394 12) exchange the motherboard.
1396 To compile this driver as a module, choose M here: the
1397 module will be called apm.
1399 if APM
1401 config APM_IGNORE_USER_SUSPEND
1402 bool "Ignore USER SUSPEND"
1403 help
1404 This option will ignore USER SUSPEND requests. On machines with a
1405 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1406 series notebooks, it is necessary to say Y because of a BIOS bug.
1408 config APM_DO_ENABLE
1409 bool "Enable PM at boot time"
1410 ---help---
1411 Enable APM features at boot time. From page 36 of the APM BIOS
1412 specification: "When disabled, the APM BIOS does not automatically
1413 power manage devices, enter the Standby State, enter the Suspend
1414 State, or take power saving steps in response to CPU Idle calls."
1415 This driver will make CPU Idle calls when Linux is idle (unless this
1416 feature is turned off -- see "Do CPU IDLE calls", below). This
1417 should always save battery power, but more complicated APM features
1418 will be dependent on your BIOS implementation. You may need to turn
1419 this option off if your computer hangs at boot time when using APM
1420 support, or if it beeps continuously instead of suspending. Turn
1421 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1422 T400CDT. This is off by default since most machines do fine without
1423 this feature.
1425 config APM_CPU_IDLE
1426 bool "Make CPU Idle calls when idle"
1427 help
1428 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1429 On some machines, this can activate improved power savings, such as
1430 a slowed CPU clock rate, when the machine is idle. These idle calls
1431 are made after the idle loop has run for some length of time (e.g.,
1432 333 mS). On some machines, this will cause a hang at boot time or
1433 whenever the CPU becomes idle. (On machines with more than one CPU,
1434 this option does nothing.)
1436 config APM_DISPLAY_BLANK
1437 bool "Enable console blanking using APM"
1438 help
1439 Enable console blanking using the APM. Some laptops can use this to
1440 turn off the LCD backlight when the screen blanker of the Linux
1441 virtual console blanks the screen. Note that this is only used by
1442 the virtual console screen blanker, and won't turn off the backlight
1443 when using the X Window system. This also doesn't have anything to
1444 do with your VESA-compliant power-saving monitor. Further, this
1445 option doesn't work for all laptops -- it might not turn off your
1446 backlight at all, or it might print a lot of errors to the console,
1447 especially if you are using gpm.
1449 config APM_ALLOW_INTS
1450 bool "Allow interrupts during APM BIOS calls"
1451 help
1452 Normally we disable external interrupts while we are making calls to
1453 the APM BIOS as a measure to lessen the effects of a badly behaving
1454 BIOS implementation. The BIOS should reenable interrupts if it
1455 needs to. Unfortunately, some BIOSes do not -- especially those in
1456 many of the newer IBM Thinkpads. If you experience hangs when you
1457 suspend, try setting this to Y. Otherwise, say N.
1459 config APM_REAL_MODE_POWER_OFF
1460 bool "Use real mode APM BIOS call to power off"
1461 help
1462 Use real mode APM BIOS calls to switch off the computer. This is
1463 a work-around for a number of buggy BIOSes. Switch this option on if
1464 your computer crashes instead of powering off properly.
1466 endif # APM
1468 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1470 source "drivers/cpuidle/Kconfig"
1472 endmenu
1475 menu "Bus options (PCI etc.)"
1477 config PCI
1478 bool "PCI support" if !X86_VISWS && !X86_VSMP
1479 depends on !X86_VOYAGER
1480 default y
1481 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1482 help
1483 Find out whether you have a PCI motherboard. PCI is the name of a
1484 bus system, i.e. the way the CPU talks to the other stuff inside
1485 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1486 VESA. If you have PCI, say Y, otherwise N.
1488 choice
1489 prompt "PCI access mode"
1490 depends on X86_32 && PCI && !X86_VISWS
1491 default PCI_GOANY
1492 ---help---
1493 On PCI systems, the BIOS can be used to detect the PCI devices and
1494 determine their configuration. However, some old PCI motherboards
1495 have BIOS bugs and may crash if this is done. Also, some embedded
1496 PCI-based systems don't have any BIOS at all. Linux can also try to
1497 detect the PCI hardware directly without using the BIOS.
1499 With this option, you can specify how Linux should detect the
1500 PCI devices. If you choose "BIOS", the BIOS will be used,
1501 if you choose "Direct", the BIOS won't be used, and if you
1502 choose "MMConfig", then PCI Express MMCONFIG will be used.
1503 If you choose "Any", the kernel will try MMCONFIG, then the
1504 direct access method and falls back to the BIOS if that doesn't
1505 work. If unsure, go with the default, which is "Any".
1507 config PCI_GOBIOS
1508 bool "BIOS"
1510 config PCI_GOMMCONFIG
1511 bool "MMConfig"
1513 config PCI_GODIRECT
1514 bool "Direct"
1516 config PCI_GOOLPC
1517 bool "OLPC"
1518 depends on OLPC
1520 config PCI_GOANY
1521 bool "Any"
1523 endchoice
1525 config PCI_BIOS
1526 def_bool y
1527 depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1529 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1530 config PCI_DIRECT
1531 def_bool y
1532 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC) || X86_VISWS)
1534 config PCI_MMCONFIG
1535 def_bool y
1536 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1538 config PCI_OLPC
1539 def_bool y
1540 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1542 config PCI_DOMAINS
1543 def_bool y
1544 depends on PCI
1546 config PCI_MMCONFIG
1547 bool "Support mmconfig PCI config space access"
1548 depends on X86_64 && PCI && ACPI
1550 config DMAR
1551 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1552 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL
1553 help
1554 DMA remapping (DMAR) devices support enables independent address
1555 translations for Direct Memory Access (DMA) from devices.
1556 These DMA remapping devices are reported via ACPI tables
1557 and include PCI device scope covered by these DMA
1558 remapping devices.
1560 config DMAR_GFX_WA
1561 def_bool y
1562 prompt "Support for Graphics workaround"
1563 depends on DMAR
1564 help
1565 Current Graphics drivers tend to use physical address
1566 for DMA and avoid using DMA APIs. Setting this config
1567 option permits the IOMMU driver to set a unity map for
1568 all the OS-visible memory. Hence the driver can continue
1569 to use physical addresses for DMA.
1571 config DMAR_FLOPPY_WA
1572 def_bool y
1573 depends on DMAR
1574 help
1575 Floppy disk drivers are know to bypass DMA API calls
1576 thereby failing to work when IOMMU is enabled. This
1577 workaround will setup a 1:1 mapping for the first
1578 16M to make floppy (an ISA device) work.
1580 source "drivers/pci/pcie/Kconfig"
1582 source "drivers/pci/Kconfig"
1584 # x86_64 have no ISA slots, but do have ISA-style DMA.
1585 config ISA_DMA_API
1586 def_bool y
1588 if X86_32
1590 config ISA
1591 bool "ISA support"
1592 depends on !(X86_VOYAGER || X86_VISWS)
1593 help
1594 Find out whether you have ISA slots on your motherboard. ISA is the
1595 name of a bus system, i.e. the way the CPU talks to the other stuff
1596 inside your box. Other bus systems are PCI, EISA, MicroChannel
1597 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1598 newer boards don't support it. If you have ISA, say Y, otherwise N.
1600 config EISA
1601 bool "EISA support"
1602 depends on ISA
1603 ---help---
1604 The Extended Industry Standard Architecture (EISA) bus was
1605 developed as an open alternative to the IBM MicroChannel bus.
1607 The EISA bus provided some of the features of the IBM MicroChannel
1608 bus while maintaining backward compatibility with cards made for
1609 the older ISA bus. The EISA bus saw limited use between 1988 and
1610 1995 when it was made obsolete by the PCI bus.
1612 Say Y here if you are building a kernel for an EISA-based machine.
1614 Otherwise, say N.
1616 source "drivers/eisa/Kconfig"
1618 config MCA
1619 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1620 default y if X86_VOYAGER
1621 help
1622 MicroChannel Architecture is found in some IBM PS/2 machines and
1623 laptops. It is a bus system similar to PCI or ISA. See
1624 <file:Documentation/mca.txt> (and especially the web page given
1625 there) before attempting to build an MCA bus kernel.
1627 source "drivers/mca/Kconfig"
1629 config SCx200
1630 tristate "NatSemi SCx200 support"
1631 depends on !X86_VOYAGER
1632 help
1633 This provides basic support for National Semiconductor's
1634 (now AMD's) Geode processors. The driver probes for the
1635 PCI-IDs of several on-chip devices, so its a good dependency
1636 for other scx200_* drivers.
1638 If compiled as a module, the driver is named scx200.
1640 config SCx200HR_TIMER
1641 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1642 depends on SCx200 && GENERIC_TIME
1643 default y
1644 help
1645 This driver provides a clocksource built upon the on-chip
1646 27MHz high-resolution timer. Its also a workaround for
1647 NSC Geode SC-1100's buggy TSC, which loses time when the
1648 processor goes idle (as is done by the scheduler). The
1649 other workaround is idle=poll boot option.
1651 config GEODE_MFGPT_TIMER
1652 def_bool y
1653 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
1654 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
1655 help
1656 This driver provides a clock event source based on the MFGPT
1657 timer(s) in the CS5535 and CS5536 companion chip for the geode.
1658 MFGPTs have a better resolution and max interval than the
1659 generic PIT, and are suitable for use as high-res timers.
1661 config OLPC
1662 bool "One Laptop Per Child support"
1663 default n
1664 help
1665 Add support for detecting the unique features of the OLPC
1666 XO hardware.
1668 endif # X86_32
1670 config K8_NB
1671 def_bool y
1672 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
1674 source "drivers/pcmcia/Kconfig"
1676 source "drivers/pci/hotplug/Kconfig"
1678 endmenu
1681 menu "Executable file formats / Emulations"
1683 source "fs/Kconfig.binfmt"
1685 config IA32_EMULATION
1686 bool "IA32 Emulation"
1687 depends on X86_64
1688 select COMPAT_BINFMT_ELF
1689 help
1690 Include code to run 32-bit programs under a 64-bit kernel. You should
1691 likely turn this on, unless you're 100% sure that you don't have any
1692 32-bit programs left.
1694 config IA32_AOUT
1695 tristate "IA32 a.out support"
1696 depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT
1697 help
1698 Support old a.out binaries in the 32bit emulation.
1700 config COMPAT
1701 def_bool y
1702 depends on IA32_EMULATION
1704 config COMPAT_FOR_U64_ALIGNMENT
1705 def_bool COMPAT
1706 depends on X86_64
1708 config SYSVIPC_COMPAT
1709 def_bool y
1710 depends on X86_64 && COMPAT && SYSVIPC
1712 endmenu
1715 source "net/Kconfig"
1717 source "drivers/Kconfig"
1719 source "drivers/firmware/Kconfig"
1721 source "fs/Kconfig"
1723 source "arch/x86/Kconfig.debug"
1725 source "security/Kconfig"
1727 source "crypto/Kconfig"
1729 source "arch/x86/kvm/Kconfig"
1731 source "lib/Kconfig"