| blob | 08993a38b1195fb6c838df2c76963daa9ee270e9 |
1 # Select 32 or 64 bit
2 config 64BIT
3 bool "64-bit kernel" if ARCH = "x86"
4 default ARCH = "x86_64"
5 ---help---
6 Say yes to build a 64-bit kernel - formerly known as x86_64
7 Say no to build a 32-bit kernel - formerly known as i386
9 config X86_32
10 def_bool !64BIT
12 config X86_64
13 def_bool 64BIT
15 ### Arch settings
16 config X86
17 def_bool y
18 select HAVE_AOUT if X86_32
19 select HAVE_READQ
20 select HAVE_WRITEQ
21 select HAVE_UNSTABLE_SCHED_CLOCK
22 select HAVE_IDE
23 select HAVE_OPROFILE
24 select HAVE_PERF_EVENTS if (!M386 && !M486)
25 select HAVE_IRQ_WORK
26 select HAVE_IOREMAP_PROT
27 select HAVE_KPROBES
28 select HAVE_MEMBLOCK
29 select ARCH_WANT_OPTIONAL_GPIOLIB
30 select ARCH_WANT_FRAME_POINTERS
31 select HAVE_DMA_ATTRS
32 select HAVE_KRETPROBES
33 select HAVE_OPTPROBES
34 select HAVE_FTRACE_MCOUNT_RECORD
35 select HAVE_C_RECORDMCOUNT
36 select HAVE_DYNAMIC_FTRACE
37 select HAVE_FUNCTION_TRACER
38 select HAVE_FUNCTION_GRAPH_TRACER
39 select HAVE_FUNCTION_GRAPH_FP_TEST
40 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
41 select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
42 select HAVE_SYSCALL_TRACEPOINTS
43 select HAVE_KVM
44 select HAVE_ARCH_KGDB
45 select HAVE_ARCH_TRACEHOOK
46 select HAVE_GENERIC_DMA_COHERENT if X86_32
47 select HAVE_EFFICIENT_UNALIGNED_ACCESS
48 select USER_STACKTRACE_SUPPORT
49 select HAVE_REGS_AND_STACK_ACCESS_API
50 select HAVE_DMA_API_DEBUG
51 select HAVE_KERNEL_GZIP
52 select HAVE_KERNEL_BZIP2
53 select HAVE_KERNEL_LZMA
54 select HAVE_KERNEL_LZO
55 select HAVE_HW_BREAKPOINT
56 select HAVE_MIXED_BREAKPOINTS_REGS
57 select PERF_EVENTS
58 select HAVE_PERF_EVENTS_NMI
59 select ANON_INODES
60 select HAVE_ARCH_KMEMCHECK
61 select HAVE_USER_RETURN_NOTIFIER
62 select HAVE_ARCH_JUMP_LABEL
63 select HAVE_TEXT_POKE_SMP
64 select HAVE_GENERIC_HARDIRQS
65 select HAVE_SPARSE_IRQ
66 select GENERIC_IRQ_PROBE
67 select GENERIC_PENDING_IRQ if SMP
69 config INSTRUCTION_DECODER
70 def_bool (KPROBES || PERF_EVENTS)
72 config OUTPUT_FORMAT
73 string
74 default "elf32-i386" if X86_32
75 default "elf64-x86-64" if X86_64
77 config ARCH_DEFCONFIG
78 string
79 default "arch/x86/configs/i386_defconfig" if X86_32
80 default "arch/x86/configs/x86_64_defconfig" if X86_64
82 config GENERIC_CMOS_UPDATE
83 def_bool y
85 config CLOCKSOURCE_WATCHDOG
86 def_bool y
88 config GENERIC_CLOCKEVENTS
89 def_bool y
91 config GENERIC_CLOCKEVENTS_BROADCAST
92 def_bool y
93 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
95 config LOCKDEP_SUPPORT
96 def_bool y
98 config STACKTRACE_SUPPORT
99 def_bool y
101 config HAVE_LATENCYTOP_SUPPORT
102 def_bool y
104 config MMU
105 def_bool y
107 config ZONE_DMA
108 def_bool y
110 config SBUS
111 bool
113 config NEED_DMA_MAP_STATE
114 def_bool (X86_64 || DMAR || DMA_API_DEBUG)
116 config NEED_SG_DMA_LENGTH
117 def_bool y
119 config GENERIC_ISA_DMA
120 def_bool y
122 config GENERIC_IOMAP
123 def_bool y
125 config GENERIC_BUG
126 def_bool y
127 depends on BUG
128 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
130 config GENERIC_BUG_RELATIVE_POINTERS
131 bool
133 config GENERIC_HWEIGHT
134 def_bool y
136 config GENERIC_GPIO
137 bool
139 config ARCH_MAY_HAVE_PC_FDC
140 def_bool y
142 config RWSEM_GENERIC_SPINLOCK
143 def_bool !X86_XADD
145 config RWSEM_XCHGADD_ALGORITHM
146 def_bool X86_XADD
148 config ARCH_HAS_CPU_IDLE_WAIT
149 def_bool y
151 config GENERIC_CALIBRATE_DELAY
152 def_bool y
154 config GENERIC_TIME_VSYSCALL
155 bool
156 default X86_64
158 config ARCH_HAS_CPU_RELAX
159 def_bool y
161 config ARCH_HAS_DEFAULT_IDLE
162 def_bool y
164 config ARCH_HAS_CACHE_LINE_SIZE
165 def_bool y
167 config HAVE_SETUP_PER_CPU_AREA
168 def_bool y
170 config NEED_PER_CPU_EMBED_FIRST_CHUNK
171 def_bool y
173 config NEED_PER_CPU_PAGE_FIRST_CHUNK
174 def_bool y
176 config HAVE_CPUMASK_OF_CPU_MAP
177 def_bool X86_64_SMP
179 config ARCH_HIBERNATION_POSSIBLE
180 def_bool y
182 config ARCH_SUSPEND_POSSIBLE
183 def_bool y
185 config ZONE_DMA32
186 bool
187 default X86_64
189 config ARCH_POPULATES_NODE_MAP
190 def_bool y
192 config AUDIT_ARCH
193 bool
194 default X86_64
196 config ARCH_SUPPORTS_OPTIMIZED_INLINING
197 def_bool y
199 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
200 def_bool y
202 config HAVE_INTEL_TXT
203 def_bool y
204 depends on EXPERIMENTAL && DMAR && ACPI
206 config USE_GENERIC_SMP_HELPERS
207 def_bool y
208 depends on SMP
210 config X86_32_SMP
211 def_bool y
212 depends on X86_32 && SMP
214 config X86_64_SMP
215 def_bool y
216 depends on X86_64 && SMP
218 config X86_HT
219 def_bool y
220 depends on SMP
222 config X86_TRAMPOLINE
223 def_bool y
224 depends on SMP || (64BIT && ACPI_SLEEP)
226 config X86_32_LAZY_GS
227 def_bool y
228 depends on X86_32 && !CC_STACKPROTECTOR
230 config ARCH_HWEIGHT_CFLAGS
231 string
232 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
233 default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64
235 config KTIME_SCALAR
236 def_bool X86_32
238 config ARCH_CPU_PROBE_RELEASE
239 def_bool y
240 depends on HOTPLUG_CPU
242 source "init/Kconfig"
243 source "kernel/Kconfig.freezer"
245 menu "Processor type and features"
247 source "kernel/time/Kconfig"
249 config SMP
250 bool "Symmetric multi-processing support"
251 ---help---
252 This enables support for systems with more than one CPU. If you have
253 a system with only one CPU, like most personal computers, say N. If
254 you have a system with more than one CPU, say Y.
256 If you say N here, the kernel will run on single and multiprocessor
257 machines, but will use only one CPU of a multiprocessor machine. If
258 you say Y here, the kernel will run on many, but not all,
259 singleprocessor machines. On a singleprocessor machine, the kernel
260 will run faster if you say N here.
262 Note that if you say Y here and choose architecture "586" or
263 "Pentium" under "Processor family", the kernel will not work on 486
264 architectures. Similarly, multiprocessor kernels for the "PPro"
265 architecture may not work on all Pentium based boards.
267 People using multiprocessor machines who say Y here should also say
268 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
269 Management" code will be disabled if you say Y here.
271 See also <file:Documentation/i386/IO-APIC.txt>,
272 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
273 <http://www.tldp.org/docs.html#howto>.
275 If you don't know what to do here, say N.
277 config X86_X2APIC
278 bool "Support x2apic"
279 depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
280 ---help---
281 This enables x2apic support on CPUs that have this feature.
283 This allows 32-bit apic IDs (so it can support very large systems),
284 and accesses the local apic via MSRs not via mmio.
286 If you don't know what to do here, say N.
288 config X86_MPPARSE
289 bool "Enable MPS table" if ACPI
290 default y
291 depends on X86_LOCAL_APIC
292 ---help---
293 For old smp systems that do not have proper acpi support. Newer systems
294 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
296 config X86_BIGSMP
297 bool "Support for big SMP systems with more than 8 CPUs"
298 depends on X86_32 && SMP
299 ---help---
300 This option is needed for the systems that have more than 8 CPUs
302 if X86_32
303 config X86_EXTENDED_PLATFORM
304 bool "Support for extended (non-PC) x86 platforms"
305 default y
306 ---help---
307 If you disable this option then the kernel will only support
308 standard PC platforms. (which covers the vast majority of
309 systems out there.)
311 If you enable this option then you'll be able to select support
312 for the following (non-PC) 32 bit x86 platforms:
313 AMD Elan
314 NUMAQ (IBM/Sequent)
315 RDC R-321x SoC
316 SGI 320/540 (Visual Workstation)
317 Summit/EXA (IBM x440)
318 Unisys ES7000 IA32 series
319 Moorestown MID devices
321 If you have one of these systems, or if you want to build a
322 generic distribution kernel, say Y here - otherwise say N.
323 endif
325 if X86_64
326 config X86_EXTENDED_PLATFORM
327 bool "Support for extended (non-PC) x86 platforms"
328 default y
329 ---help---
330 If you disable this option then the kernel will only support
331 standard PC platforms. (which covers the vast majority of
332 systems out there.)
334 If you enable this option then you'll be able to select support
335 for the following (non-PC) 64 bit x86 platforms:
336 ScaleMP vSMP
337 SGI Ultraviolet
339 If you have one of these systems, or if you want to build a
340 generic distribution kernel, say Y here - otherwise say N.
341 endif
342 # This is an alphabetically sorted list of 64 bit extended platforms
343 # Please maintain the alphabetic order if and when there are additions
345 config X86_VSMP
346 bool "ScaleMP vSMP"
347 select PARAVIRT_GUEST
348 select PARAVIRT
349 depends on X86_64 && PCI
350 depends on X86_EXTENDED_PLATFORM
351 ---help---
352 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
353 supposed to run on these EM64T-based machines. Only choose this option
354 if you have one of these machines.
356 config X86_UV
357 bool "SGI Ultraviolet"
358 depends on X86_64
359 depends on X86_EXTENDED_PLATFORM
360 depends on NUMA
361 depends on X86_X2APIC
362 ---help---
363 This option is needed in order to support SGI Ultraviolet systems.
364 If you don't have one of these, you should say N here.
366 # Following is an alphabetically sorted list of 32 bit extended platforms
367 # Please maintain the alphabetic order if and when there are additions
369 config X86_ELAN
370 bool "AMD Elan"
371 depends on X86_32
372 depends on X86_EXTENDED_PLATFORM
373 ---help---
374 Select this for an AMD Elan processor.
376 Do not use this option for K6/Athlon/Opteron processors!
378 If unsure, choose "PC-compatible" instead.
380 config X86_MRST
381 bool "Moorestown MID platform"
382 depends on PCI
383 depends on PCI_GOANY
384 depends on X86_32
385 depends on X86_EXTENDED_PLATFORM
386 depends on X86_IO_APIC
387 select APB_TIMER
388 ---help---
389 Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
390 Internet Device(MID) platform. Moorestown consists of two chips:
391 Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
392 Unlike standard x86 PCs, Moorestown does not have many legacy devices
393 nor standard legacy replacement devices/features. e.g. Moorestown does
394 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
396 config X86_RDC321X
397 bool "RDC R-321x SoC"
398 depends on X86_32
399 depends on X86_EXTENDED_PLATFORM
400 select M486
401 select X86_REBOOTFIXUPS
402 ---help---
403 This option is needed for RDC R-321x system-on-chip, also known
404 as R-8610-(G).
405 If you don't have one of these chips, you should say N here.
407 config X86_32_NON_STANDARD
408 bool "Support non-standard 32-bit SMP architectures"
409 depends on X86_32 && SMP
410 depends on X86_EXTENDED_PLATFORM
411 ---help---
412 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
413 subarchitectures. It is intended for a generic binary kernel.
414 if you select them all, kernel will probe it one by one. and will
415 fallback to default.
417 # Alphabetically sorted list of Non standard 32 bit platforms
419 config X86_NUMAQ
420 bool "NUMAQ (IBM/Sequent)"
421 depends on X86_32_NON_STANDARD
422 depends on PCI
423 select NUMA
424 select X86_MPPARSE
425 ---help---
426 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
427 NUMA multiquad box. This changes the way that processors are
428 bootstrapped, and uses Clustered Logical APIC addressing mode instead
429 of Flat Logical. You will need a new lynxer.elf file to flash your
430 firmware with - send email to <Martin.Bligh@us.ibm.com>.
432 config X86_SUPPORTS_MEMORY_FAILURE
433 def_bool y
434 # MCE code calls memory_failure():
435 depends on X86_MCE
436 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
437 depends on !X86_NUMAQ
438 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
439 depends on X86_64 || !SPARSEMEM
440 select ARCH_SUPPORTS_MEMORY_FAILURE
442 config X86_VISWS
443 bool "SGI 320/540 (Visual Workstation)"
444 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
445 depends on X86_32_NON_STANDARD
446 ---help---
447 The SGI Visual Workstation series is an IA32-based workstation
448 based on SGI systems chips with some legacy PC hardware attached.
450 Say Y here to create a kernel to run on the SGI 320 or 540.
452 A kernel compiled for the Visual Workstation will run on general
453 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
455 config X86_SUMMIT
456 bool "Summit/EXA (IBM x440)"
457 depends on X86_32_NON_STANDARD
458 ---help---
459 This option is needed for IBM systems that use the Summit/EXA chipset.
460 In particular, it is needed for the x440.
462 config X86_ES7000
463 bool "Unisys ES7000 IA32 series"
464 depends on X86_32_NON_STANDARD && X86_BIGSMP
465 ---help---
466 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
467 supposed to run on an IA32-based Unisys ES7000 system.
469 config SCHED_OMIT_FRAME_POINTER
470 def_bool y
471 prompt "Single-depth WCHAN output"
472 depends on X86
473 ---help---
474 Calculate simpler /proc/<PID>/wchan values. If this option
475 is disabled then wchan values will recurse back to the
476 caller function. This provides more accurate wchan values,
477 at the expense of slightly more scheduling overhead.
479 If in doubt, say "Y".
481 menuconfig PARAVIRT_GUEST
482 bool "Paravirtualized guest support"
483 ---help---
484 Say Y here to get to see options related to running Linux under
485 various hypervisors. This option alone does not add any kernel code.
487 If you say N, all options in this submenu will be skipped and disabled.
489 if PARAVIRT_GUEST
491 source "arch/x86/xen/Kconfig"
493 config KVM_CLOCK
494 bool "KVM paravirtualized clock"
495 select PARAVIRT
496 select PARAVIRT_CLOCK
497 ---help---
498 Turning on this option will allow you to run a paravirtualized clock
499 when running over the KVM hypervisor. Instead of relying on a PIT
500 (or probably other) emulation by the underlying device model, the host
501 provides the guest with timing infrastructure such as time of day, and
502 system time
504 config KVM_GUEST
505 bool "KVM Guest support"
506 select PARAVIRT
507 ---help---
508 This option enables various optimizations for running under the KVM
509 hypervisor.
511 source "arch/x86/lguest/Kconfig"
513 config PARAVIRT
514 bool "Enable paravirtualization code"
515 ---help---
516 This changes the kernel so it can modify itself when it is run
517 under a hypervisor, potentially improving performance significantly
518 over full virtualization. However, when run without a hypervisor
519 the kernel is theoretically slower and slightly larger.
521 config PARAVIRT_SPINLOCKS
522 bool "Paravirtualization layer for spinlocks"
523 depends on PARAVIRT && SMP && EXPERIMENTAL
524 ---help---
525 Paravirtualized spinlocks allow a pvops backend to replace the
526 spinlock implementation with something virtualization-friendly
527 (for example, block the virtual CPU rather than spinning).
529 Unfortunately the downside is an up to 5% performance hit on
530 native kernels, with various workloads.
532 If you are unsure how to answer this question, answer N.
534 config PARAVIRT_CLOCK
535 bool
537 endif
539 config PARAVIRT_DEBUG
540 bool "paravirt-ops debugging"
541 depends on PARAVIRT && DEBUG_KERNEL
542 ---help---
543 Enable to debug paravirt_ops internals. Specifically, BUG if
544 a paravirt_op is missing when it is called.
546 config NO_BOOTMEM
547 def_bool y
549 config MEMTEST
550 bool "Memtest"
551 ---help---
552 This option adds a kernel parameter 'memtest', which allows memtest
553 to be set.
554 memtest=0, mean disabled; -- default
555 memtest=1, mean do 1 test pattern;
556 ...
557 memtest=4, mean do 4 test patterns.
558 If you are unsure how to answer this question, answer N.
560 config X86_SUMMIT_NUMA
561 def_bool y
562 depends on X86_32 && NUMA && X86_32_NON_STANDARD
564 config X86_CYCLONE_TIMER
565 def_bool y
566 depends on X86_32_NON_STANDARD
568 source "arch/x86/Kconfig.cpu"
570 config HPET_TIMER
571 def_bool X86_64
572 prompt "HPET Timer Support" if X86_32
573 ---help---
574 Use the IA-PC HPET (High Precision Event Timer) to manage
575 time in preference to the PIT and RTC, if a HPET is
576 present.
577 HPET is the next generation timer replacing legacy 8254s.
578 The HPET provides a stable time base on SMP
579 systems, unlike the TSC, but it is more expensive to access,
580 as it is off-chip. You can find the HPET spec at
581 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
583 You can safely choose Y here. However, HPET will only be
584 activated if the platform and the BIOS support this feature.
585 Otherwise the 8254 will be used for timing services.
587 Choose N to continue using the legacy 8254 timer.
589 config HPET_EMULATE_RTC
590 def_bool y
591 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
593 config APB_TIMER
594 def_bool y if MRST
595 prompt "Langwell APB Timer Support" if X86_MRST
596 help
597 APB timer is the replacement for 8254, HPET on X86 MID platforms.
598 The APBT provides a stable time base on SMP
599 systems, unlike the TSC, but it is more expensive to access,
600 as it is off-chip. APB timers are always running regardless of CPU
601 C states, they are used as per CPU clockevent device when possible.
603 # Mark as embedded because too many people got it wrong.
604 # The code disables itself when not needed.
605 config DMI
606 default y
607 bool "Enable DMI scanning" if EMBEDDED
608 ---help---
609 Enabled scanning of DMI to identify machine quirks. Say Y
610 here unless you have verified that your setup is not
611 affected by entries in the DMI blacklist. Required by PNP
612 BIOS code.
614 config GART_IOMMU
615 bool "GART IOMMU support" if EMBEDDED
616 default y
617 select SWIOTLB
618 depends on X86_64 && PCI && AMD_NB
619 ---help---
620 Support for full DMA access of devices with 32bit memory access only
621 on systems with more than 3GB. This is usually needed for USB,
622 sound, many IDE/SATA chipsets and some other devices.
623 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
624 based hardware IOMMU and a software bounce buffer based IOMMU used
625 on Intel systems and as fallback.
626 The code is only active when needed (enough memory and limited
627 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
628 too.
630 config CALGARY_IOMMU
631 bool "IBM Calgary IOMMU support"
632 select SWIOTLB
633 depends on X86_64 && PCI && EXPERIMENTAL
634 ---help---
635 Support for hardware IOMMUs in IBM's xSeries x366 and x460
636 systems. Needed to run systems with more than 3GB of memory
637 properly with 32-bit PCI devices that do not support DAC
638 (Double Address Cycle). Calgary also supports bus level
639 isolation, where all DMAs pass through the IOMMU. This
640 prevents them from going anywhere except their intended
641 destination. This catches hard-to-find kernel bugs and
642 mis-behaving drivers and devices that do not use the DMA-API
643 properly to set up their DMA buffers. The IOMMU can be
644 turned off at boot time with the iommu=off parameter.
645 Normally the kernel will make the right choice by itself.
646 If unsure, say Y.
648 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
649 def_bool y
650 prompt "Should Calgary be enabled by default?"
651 depends on CALGARY_IOMMU
652 ---help---
653 Should Calgary be enabled by default? if you choose 'y', Calgary
654 will be used (if it exists). If you choose 'n', Calgary will not be
655 used even if it exists. If you choose 'n' and would like to use
656 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
657 If unsure, say Y.
659 config AMD_IOMMU
660 bool "AMD IOMMU support"
661 select SWIOTLB
662 select PCI_MSI
663 depends on X86_64 && PCI && ACPI
664 ---help---
665 With this option you can enable support for AMD IOMMU hardware in
666 your system. An IOMMU is a hardware component which provides
667 remapping of DMA memory accesses from devices. With an AMD IOMMU you
668 can isolate the the DMA memory of different devices and protect the
669 system from misbehaving device drivers or hardware.
671 You can find out if your system has an AMD IOMMU if you look into
672 your BIOS for an option to enable it or if you have an IVRS ACPI
673 table.
675 config AMD_IOMMU_STATS
676 bool "Export AMD IOMMU statistics to debugfs"
677 depends on AMD_IOMMU
678 select DEBUG_FS
679 ---help---
680 This option enables code in the AMD IOMMU driver to collect various
681 statistics about whats happening in the driver and exports that
682 information to userspace via debugfs.
683 If unsure, say N.
685 # need this always selected by IOMMU for the VIA workaround
686 config SWIOTLB
687 def_bool y if X86_64
688 ---help---
689 Support for software bounce buffers used on x86-64 systems
690 which don't have a hardware IOMMU (e.g. the current generation
691 of Intel's x86-64 CPUs). Using this PCI devices which can only
692 access 32-bits of memory can be used on systems with more than
693 3 GB of memory. If unsure, say Y.
695 config IOMMU_HELPER
696 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
698 config IOMMU_API
699 def_bool (AMD_IOMMU || DMAR)
701 config MAXSMP
702 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
703 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
704 select CPUMASK_OFFSTACK
705 ---help---
706 Enable maximum number of CPUS and NUMA Nodes for this architecture.
707 If unsure, say N.
709 config NR_CPUS
710 int "Maximum number of CPUs" if SMP && !MAXSMP
711 range 2 8 if SMP && X86_32 && !X86_BIGSMP
712 range 2 512 if SMP && !MAXSMP
713 default "1" if !SMP
714 default "4096" if MAXSMP
715 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
716 default "8" if SMP
717 ---help---
718 This allows you to specify the maximum number of CPUs which this
719 kernel will support. The maximum supported value is 512 and the
720 minimum value which makes sense is 2.
722 This is purely to save memory - each supported CPU adds
723 approximately eight kilobytes to the kernel image.
725 config SCHED_SMT
726 bool "SMT (Hyperthreading) scheduler support"
727 depends on X86_HT
728 ---help---
729 SMT scheduler support improves the CPU scheduler's decision making
730 when dealing with Intel Pentium 4 chips with HyperThreading at a
731 cost of slightly increased overhead in some places. If unsure say
732 N here.
734 config SCHED_MC
735 def_bool y
736 prompt "Multi-core scheduler support"
737 depends on X86_HT
738 ---help---
739 Multi-core scheduler support improves the CPU scheduler's decision
740 making when dealing with multi-core CPU chips at a cost of slightly
741 increased overhead in some places. If unsure say N here.
743 config IRQ_TIME_ACCOUNTING
744 bool "Fine granularity task level IRQ time accounting"
745 default n
746 ---help---
747 Select this option to enable fine granularity task irq time
748 accounting. This is done by reading a timestamp on each
749 transitions between softirq and hardirq state, so there can be a
750 small performance impact.
752 If in doubt, say N here.
754 source "kernel/Kconfig.preempt"
756 config X86_UP_APIC
757 bool "Local APIC support on uniprocessors"
758 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
759 ---help---
760 A local APIC (Advanced Programmable Interrupt Controller) is an
761 integrated interrupt controller in the CPU. If you have a single-CPU
762 system which has a processor with a local APIC, you can say Y here to
763 enable and use it. If you say Y here even though your machine doesn't
764 have a local APIC, then the kernel will still run with no slowdown at
765 all. The local APIC supports CPU-generated self-interrupts (timer,
766 performance counters), and the NMI watchdog which detects hard
767 lockups.
769 config X86_UP_IOAPIC
770 bool "IO-APIC support on uniprocessors"
771 depends on X86_UP_APIC
772 ---help---
773 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
774 SMP-capable replacement for PC-style interrupt controllers. Most
775 SMP systems and many recent uniprocessor systems have one.
777 If you have a single-CPU system with an IO-APIC, you can say Y here
778 to use it. If you say Y here even though your machine doesn't have
779 an IO-APIC, then the kernel will still run with no slowdown at all.
781 config X86_LOCAL_APIC
782 def_bool y
783 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
785 config X86_IO_APIC
786 def_bool y
787 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
789 config X86_VISWS_APIC
790 def_bool y
791 depends on X86_32 && X86_VISWS
793 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
794 bool "Reroute for broken boot IRQs"
795 depends on X86_IO_APIC
796 ---help---
797 This option enables a workaround that fixes a source of
798 spurious interrupts. This is recommended when threaded
799 interrupt handling is used on systems where the generation of
800 superfluous "boot interrupts" cannot be disabled.
802 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
803 entry in the chipset's IO-APIC is masked (as, e.g. the RT
804 kernel does during interrupt handling). On chipsets where this
805 boot IRQ generation cannot be disabled, this workaround keeps
806 the original IRQ line masked so that only the equivalent "boot
807 IRQ" is delivered to the CPUs. The workaround also tells the
808 kernel to set up the IRQ handler on the boot IRQ line. In this
809 way only one interrupt is delivered to the kernel. Otherwise
810 the spurious second interrupt may cause the kernel to bring
811 down (vital) interrupt lines.
813 Only affects "broken" chipsets. Interrupt sharing may be
814 increased on these systems.
816 config X86_MCE
817 bool "Machine Check / overheating reporting"
818 ---help---
819 Machine Check support allows the processor to notify the
820 kernel if it detects a problem (e.g. overheating, data corruption).
821 The action the kernel takes depends on the severity of the problem,
822 ranging from warning messages to halting the machine.
824 config X86_MCE_INTEL
825 def_bool y
826 prompt "Intel MCE features"
827 depends on X86_MCE && X86_LOCAL_APIC
828 ---help---
829 Additional support for intel specific MCE features such as
830 the thermal monitor.
832 config X86_MCE_AMD
833 def_bool y
834 prompt "AMD MCE features"
835 depends on X86_MCE && X86_LOCAL_APIC
836 ---help---
837 Additional support for AMD specific MCE features such as
838 the DRAM Error Threshold.
840 config X86_ANCIENT_MCE
841 bool "Support for old Pentium 5 / WinChip machine checks"
842 depends on X86_32 && X86_MCE
843 ---help---
844 Include support for machine check handling on old Pentium 5 or WinChip
845 systems. These typically need to be enabled explicitely on the command
846 line.
848 config X86_MCE_THRESHOLD
849 depends on X86_MCE_AMD || X86_MCE_INTEL
850 def_bool y
852 config X86_MCE_INJECT
853 depends on X86_MCE
854 tristate "Machine check injector support"
855 ---help---
856 Provide support for injecting machine checks for testing purposes.
857 If you don't know what a machine check is and you don't do kernel
858 QA it is safe to say n.
860 config X86_THERMAL_VECTOR
861 def_bool y
862 depends on X86_MCE_INTEL
864 config VM86
865 bool "Enable VM86 support" if EMBEDDED
866 default y
867 depends on X86_32
868 ---help---
869 This option is required by programs like DOSEMU to run 16-bit legacy
870 code on X86 processors. It also may be needed by software like
871 XFree86 to initialize some video cards via BIOS. Disabling this
872 option saves about 6k.
874 config TOSHIBA
875 tristate "Toshiba Laptop support"
876 depends on X86_32
877 ---help---
878 This adds a driver to safely access the System Management Mode of
879 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
880 not work on models with a Phoenix BIOS. The System Management Mode
881 is used to set the BIOS and power saving options on Toshiba portables.
883 For information on utilities to make use of this driver see the
884 Toshiba Linux utilities web site at:
885 <http://www.buzzard.org.uk/toshiba/>.
887 Say Y if you intend to run this kernel on a Toshiba portable.
888 Say N otherwise.
890 config I8K
891 tristate "Dell laptop support"
892 ---help---
893 This adds a driver to safely access the System Management Mode
894 of the CPU on the Dell Inspiron 8000. The System Management Mode
895 is used to read cpu temperature and cooling fan status and to
896 control the fans on the I8K portables.
898 This driver has been tested only on the Inspiron 8000 but it may
899 also work with other Dell laptops. You can force loading on other
900 models by passing the parameter `force=1' to the module. Use at
901 your own risk.
903 For information on utilities to make use of this driver see the
904 I8K Linux utilities web site at:
905 <http://people.debian.org/~dz/i8k/>
907 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
908 Say N otherwise.
910 config X86_REBOOTFIXUPS
911 bool "Enable X86 board specific fixups for reboot"
912 depends on X86_32
913 ---help---
914 This enables chipset and/or board specific fixups to be done
915 in order to get reboot to work correctly. This is only needed on
916 some combinations of hardware and BIOS. The symptom, for which
917 this config is intended, is when reboot ends with a stalled/hung
918 system.
920 Currently, the only fixup is for the Geode machines using
921 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
923 Say Y if you want to enable the fixup. Currently, it's safe to
924 enable this option even if you don't need it.
925 Say N otherwise.
927 config MICROCODE
928 tristate "/dev/cpu/microcode - microcode support"
929 select FW_LOADER
930 ---help---
931 If you say Y here, you will be able to update the microcode on
932 certain Intel and AMD processors. The Intel support is for the
933 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
934 Pentium 4, Xeon etc. The AMD support is for family 0x10 and
935 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
936 You will obviously need the actual microcode binary data itself
937 which is not shipped with the Linux kernel.
939 This option selects the general module only, you need to select
940 at least one vendor specific module as well.
942 To compile this driver as a module, choose M here: the
943 module will be called microcode.
945 config MICROCODE_INTEL
946 bool "Intel microcode patch loading support"
947 depends on MICROCODE
948 default MICROCODE
949 select FW_LOADER
950 ---help---
951 This options enables microcode patch loading support for Intel
952 processors.
954 For latest news and information on obtaining all the required
955 Intel ingredients for this driver, check:
956 <http://www.urbanmyth.org/microcode/>.
958 config MICROCODE_AMD
959 bool "AMD microcode patch loading support"
960 depends on MICROCODE
961 select FW_LOADER
962 ---help---
963 If you select this option, microcode patch loading support for AMD
964 processors will be enabled.
966 config MICROCODE_OLD_INTERFACE
967 def_bool y
968 depends on MICROCODE
970 config X86_MSR
971 tristate "/dev/cpu/*/msr - Model-specific register support"
972 ---help---
973 This device gives privileged processes access to the x86
974 Model-Specific Registers (MSRs). It is a character device with
975 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
976 MSR accesses are directed to a specific CPU on multi-processor
977 systems.
979 config X86_CPUID
980 tristate "/dev/cpu/*/cpuid - CPU information support"
981 ---help---
982 This device gives processes access to the x86 CPUID instruction to
983 be executed on a specific processor. It is a character device
984 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
985 /dev/cpu/31/cpuid.
987 choice
988 prompt "High Memory Support"
989 default HIGHMEM64G if X86_NUMAQ
990 default HIGHMEM4G
991 depends on X86_32
993 config NOHIGHMEM
994 bool "off"
995 depends on !X86_NUMAQ
996 ---help---
997 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
998 However, the address space of 32-bit x86 processors is only 4
999 Gigabytes large. That means that, if you have a large amount of
1000 physical memory, not all of it can be "permanently mapped" by the
1001 kernel. The physical memory that's not permanently mapped is called
1002 "high memory".
1004 If you are compiling a kernel which will never run on a machine with
1005 more than 1 Gigabyte total physical RAM, answer "off" here (default
1006 choice and suitable for most users). This will result in a "3GB/1GB"
1007 split: 3GB are mapped so that each process sees a 3GB virtual memory
1008 space and the remaining part of the 4GB virtual memory space is used
1009 by the kernel to permanently map as much physical memory as
1010 possible.
1012 If the machine has between 1 and 4 Gigabytes physical RAM, then
1013 answer "4GB" here.
1015 If more than 4 Gigabytes is used then answer "64GB" here. This
1016 selection turns Intel PAE (Physical Address Extension) mode on.
1017 PAE implements 3-level paging on IA32 processors. PAE is fully
1018 supported by Linux, PAE mode is implemented on all recent Intel
1019 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1020 then the kernel will not boot on CPUs that don't support PAE!
1022 The actual amount of total physical memory will either be
1023 auto detected or can be forced by using a kernel command line option
1024 such as "mem=256M". (Try "man bootparam" or see the documentation of
1025 your boot loader (lilo or loadlin) about how to pass options to the
1026 kernel at boot time.)
1028 If unsure, say "off".
1030 config HIGHMEM4G
1031 bool "4GB"
1032 depends on !X86_NUMAQ
1033 ---help---
1034 Select this if you have a 32-bit processor and between 1 and 4
1035 gigabytes of physical RAM.
1037 config HIGHMEM64G
1038 bool "64GB"
1039 depends on !M386 && !M486
1040 select X86_PAE
1041 ---help---
1042 Select this if you have a 32-bit processor and more than 4
1043 gigabytes of physical RAM.
1045 endchoice
1047 choice
1048 depends on EXPERIMENTAL
1049 prompt "Memory split" if EMBEDDED
1050 default VMSPLIT_3G
1051 depends on X86_32
1052 ---help---
1053 Select the desired split between kernel and user memory.
1055 If the address range available to the kernel is less than the
1056 physical memory installed, the remaining memory will be available
1057 as "high memory". Accessing high memory is a little more costly
1058 than low memory, as it needs to be mapped into the kernel first.
1059 Note that increasing the kernel address space limits the range
1060 available to user programs, making the address space there
1061 tighter. Selecting anything other than the default 3G/1G split
1062 will also likely make your kernel incompatible with binary-only
1063 kernel modules.
1065 If you are not absolutely sure what you are doing, leave this
1066 option alone!
1068 config VMSPLIT_3G
1069 bool "3G/1G user/kernel split"
1070 config VMSPLIT_3G_OPT
1071 depends on !X86_PAE
1072 bool "3G/1G user/kernel split (for full 1G low memory)"
1073 config VMSPLIT_2G
1074 bool "2G/2G user/kernel split"
1075 config VMSPLIT_2G_OPT
1076 depends on !X86_PAE
1077 bool "2G/2G user/kernel split (for full 2G low memory)"
1078 config VMSPLIT_1G
1079 bool "1G/3G user/kernel split"
1080 endchoice
1082 config PAGE_OFFSET
1083 hex
1084 default 0xB0000000 if VMSPLIT_3G_OPT
1085 default 0x80000000 if VMSPLIT_2G
1086 default 0x78000000 if VMSPLIT_2G_OPT
1087 default 0x40000000 if VMSPLIT_1G
1088 default 0xC0000000
1089 depends on X86_32
1091 config HIGHMEM
1092 def_bool y
1093 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1095 config X86_PAE
1096 bool "PAE (Physical Address Extension) Support"
1097 depends on X86_32 && !HIGHMEM4G
1098 ---help---
1099 PAE is required for NX support, and furthermore enables
1100 larger swapspace support for non-overcommit purposes. It
1101 has the cost of more pagetable lookup overhead, and also
1102 consumes more pagetable space per process.
1104 config ARCH_PHYS_ADDR_T_64BIT
1105 def_bool X86_64 || X86_PAE
1107 config ARCH_DMA_ADDR_T_64BIT
1108 def_bool X86_64 || HIGHMEM64G
1110 config DIRECT_GBPAGES
1111 bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
1112 default y
1113 depends on X86_64
1114 ---help---
1115 Allow the kernel linear mapping to use 1GB pages on CPUs that
1116 support it. This can improve the kernel's performance a tiny bit by
1117 reducing TLB pressure. If in doubt, say "Y".
1119 # Common NUMA Features
1120 config NUMA
1121 bool "Numa Memory Allocation and Scheduler Support"
1122 depends on SMP
1123 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1124 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1125 ---help---
1126 Enable NUMA (Non Uniform Memory Access) support.
1128 The kernel will try to allocate memory used by a CPU on the
1129 local memory controller of the CPU and add some more
1130 NUMA awareness to the kernel.
1132 For 64-bit this is recommended if the system is Intel Core i7
1133 (or later), AMD Opteron, or EM64T NUMA.
1135 For 32-bit this is only needed on (rare) 32-bit-only platforms
1136 that support NUMA topologies, such as NUMAQ / Summit, or if you
1137 boot a 32-bit kernel on a 64-bit NUMA platform.
1139 Otherwise, you should say N.
1141 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1142 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1144 config AMD_NUMA
1145 def_bool y
1146 prompt "Old style AMD Opteron NUMA detection"
1147 depends on X86_64 && NUMA && PCI
1148 ---help---
1149 Enable AMD NUMA node topology detection. You should say Y here if
1150 you have a multi processor AMD system. This uses an old method to
1151 read the NUMA configuration directly from the builtin Northbridge
1152 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1153 which also takes priority if both are compiled in.
1155 config X86_64_ACPI_NUMA
1156 def_bool y
1157 prompt "ACPI NUMA detection"
1158 depends on X86_64 && NUMA && ACPI && PCI
1159 select ACPI_NUMA
1160 ---help---
1161 Enable ACPI SRAT based node topology detection.
1163 # Some NUMA nodes have memory ranges that span
1164 # other nodes. Even though a pfn is valid and
1165 # between a node's start and end pfns, it may not
1166 # reside on that node. See memmap_init_zone()
1167 # for details.
1168 config NODES_SPAN_OTHER_NODES
1169 def_bool y
1170 depends on X86_64_ACPI_NUMA
1172 config NUMA_EMU
1173 bool "NUMA emulation"
1174 depends on X86_64 && NUMA
1175 ---help---
1176 Enable NUMA emulation. A flat machine will be split
1177 into virtual nodes when booted with "numa=fake=N", where N is the
1178 number of nodes. This is only useful for debugging.
1180 config NODES_SHIFT
1181 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1182 range 1 10
1183 default "10" if MAXSMP
1184 default "6" if X86_64
1185 default "4" if X86_NUMAQ
1186 default "3"
1187 depends on NEED_MULTIPLE_NODES
1188 ---help---
1189 Specify the maximum number of NUMA Nodes available on the target
1190 system. Increases memory reserved to accommodate various tables.
1192 config HAVE_ARCH_BOOTMEM
1193 def_bool y
1194 depends on X86_32 && NUMA
1196 config ARCH_HAVE_MEMORY_PRESENT
1197 def_bool y
1198 depends on X86_32 && DISCONTIGMEM
1200 config NEED_NODE_MEMMAP_SIZE
1201 def_bool y
1202 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1204 config HAVE_ARCH_ALLOC_REMAP
1205 def_bool y
1206 depends on X86_32 && NUMA
1208 config ARCH_FLATMEM_ENABLE
1209 def_bool y
1210 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
1212 config ARCH_DISCONTIGMEM_ENABLE
1213 def_bool y
1214 depends on NUMA && X86_32
1216 config ARCH_DISCONTIGMEM_DEFAULT
1217 def_bool y
1218 depends on NUMA && X86_32
1220 config ARCH_PROC_KCORE_TEXT
1221 def_bool y
1222 depends on X86_64 && PROC_KCORE
1224 config ARCH_SPARSEMEM_DEFAULT
1225 def_bool y
1226 depends on X86_64
1228 config ARCH_SPARSEMEM_ENABLE
1229 def_bool y
1230 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1231 select SPARSEMEM_STATIC if X86_32
1232 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1234 config ARCH_SELECT_MEMORY_MODEL
1235 def_bool y
1236 depends on ARCH_SPARSEMEM_ENABLE
1238 config ARCH_MEMORY_PROBE
1239 def_bool X86_64
1240 depends on MEMORY_HOTPLUG
1242 config ILLEGAL_POINTER_VALUE
1243 hex
1244 default 0 if X86_32
1245 default 0xdead000000000000 if X86_64
1247 source "mm/Kconfig"
1249 config HIGHPTE
1250 bool "Allocate 3rd-level pagetables from highmem"
1251 depends on HIGHMEM
1252 ---help---
1253 The VM uses one page table entry for each page of physical memory.
1254 For systems with a lot of RAM, this can be wasteful of precious
1255 low memory. Setting this option will put user-space page table
1256 entries in high memory.
1258 config X86_CHECK_BIOS_CORRUPTION
1259 bool "Check for low memory corruption"
1260 ---help---
1261 Periodically check for memory corruption in low memory, which
1262 is suspected to be caused by BIOS. Even when enabled in the
1263 configuration, it is disabled at runtime. Enable it by
1264 setting "memory_corruption_check=1" on the kernel command
1265 line. By default it scans the low 64k of memory every 60
1266 seconds; see the memory_corruption_check_size and
1267 memory_corruption_check_period parameters in
1268 Documentation/kernel-parameters.txt to adjust this.
1270 When enabled with the default parameters, this option has
1271 almost no overhead, as it reserves a relatively small amount
1272 of memory and scans it infrequently. It both detects corruption
1273 and prevents it from affecting the running system.
1275 It is, however, intended as a diagnostic tool; if repeatable
1276 BIOS-originated corruption always affects the same memory,
1277 you can use memmap= to prevent the kernel from using that
1278 memory.
1280 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1281 bool "Set the default setting of memory_corruption_check"
1282 depends on X86_CHECK_BIOS_CORRUPTION
1283 default y
1284 ---help---
1285 Set whether the default state of memory_corruption_check is
1286 on or off.
1288 config X86_RESERVE_LOW
1289 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1290 default 64
1291 range 4 640
1292 ---help---
1293 Specify the amount of low memory to reserve for the BIOS.
1295 The first page contains BIOS data structures that the kernel
1296 must not use, so that page must always be reserved.
1298 By default we reserve the first 64K of physical RAM, as a
1299 number of BIOSes are known to corrupt that memory range
1300 during events such as suspend/resume or monitor cable
1301 insertion, so it must not be used by the kernel.
1303 You can set this to 4 if you are absolutely sure that you
1304 trust the BIOS to get all its memory reservations and usages
1305 right. If you know your BIOS have problems beyond the
1306 default 64K area, you can set this to 640 to avoid using the
1307 entire low memory range.
1309 If you have doubts about the BIOS (e.g. suspend/resume does
1310 not work or there's kernel crashes after certain hardware
1311 hotplug events) then you might want to enable
1312 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1313 typical corruption patterns.
1315 Leave this to the default value of 64 if you are unsure.
1317 config MATH_EMULATION
1318 bool
1319 prompt "Math emulation" if X86_32
1320 ---help---
1321 Linux can emulate a math coprocessor (used for floating point
1322 operations) if you don't have one. 486DX and Pentium processors have
1323 a math coprocessor built in, 486SX and 386 do not, unless you added
1324 a 487DX or 387, respectively. (The messages during boot time can
1325 give you some hints here ["man dmesg"].) Everyone needs either a
1326 coprocessor or this emulation.
1328 If you don't have a math coprocessor, you need to say Y here; if you
1329 say Y here even though you have a coprocessor, the coprocessor will
1330 be used nevertheless. (This behavior can be changed with the kernel
1331 command line option "no387", which comes handy if your coprocessor
1332 is broken. Try "man bootparam" or see the documentation of your boot
1333 loader (lilo or loadlin) about how to pass options to the kernel at
1334 boot time.) This means that it is a good idea to say Y here if you
1335 intend to use this kernel on different machines.
1337 More information about the internals of the Linux math coprocessor
1338 emulation can be found in <file:arch/x86/math-emu/README>.
1340 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1341 kernel, it won't hurt.
1343 config MTRR
1344 def_bool y
1345 prompt "MTRR (Memory Type Range Register) support" if EMBEDDED
1346 ---help---
1347 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1348 the Memory Type Range Registers (MTRRs) may be used to control
1349 processor access to memory ranges. This is most useful if you have
1350 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1351 allows bus write transfers to be combined into a larger transfer
1352 before bursting over the PCI/AGP bus. This can increase performance
1353 of image write operations 2.5 times or more. Saying Y here creates a
1354 /proc/mtrr file which may be used to manipulate your processor's
1355 MTRRs. Typically the X server should use this.
1357 This code has a reasonably generic interface so that similar
1358 control registers on other processors can be easily supported
1359 as well:
1361 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1362 Registers (ARRs) which provide a similar functionality to MTRRs. For
1363 these, the ARRs are used to emulate the MTRRs.
1364 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1365 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1366 write-combining. All of these processors are supported by this code
1367 and it makes sense to say Y here if you have one of them.
1369 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1370 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1371 can lead to all sorts of problems, so it's good to say Y here.
1373 You can safely say Y even if your machine doesn't have MTRRs, you'll
1374 just add about 9 KB to your kernel.
1376 See <file:Documentation/x86/mtrr.txt> for more information.
1378 config MTRR_SANITIZER
1379 def_bool y
1380 prompt "MTRR cleanup support"
1381 depends on MTRR
1382 ---help---
1383 Convert MTRR layout from continuous to discrete, so X drivers can
1384 add writeback entries.
1386 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1387 The largest mtrr entry size for a continuous block can be set with
1388 mtrr_chunk_size.
1390 If unsure, say Y.
1392 config MTRR_SANITIZER_ENABLE_DEFAULT
1393 int "MTRR cleanup enable value (0-1)"
1394 range 0 1
1395 default "0"
1396 depends on MTRR_SANITIZER
1397 ---help---
1398 Enable mtrr cleanup default value
1400 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1401 int "MTRR cleanup spare reg num (0-7)"
1402 range 0 7
1403 default "1"
1404 depends on MTRR_SANITIZER
1405 ---help---
1406 mtrr cleanup spare entries default, it can be changed via
1407 mtrr_spare_reg_nr=N on the kernel command line.
1409 config X86_PAT
1410 def_bool y
1411 prompt "x86 PAT support" if EMBEDDED
1412 depends on MTRR
1413 ---help---
1414 Use PAT attributes to setup page level cache control.
1416 PATs are the modern equivalents of MTRRs and are much more
1417 flexible than MTRRs.
1419 Say N here if you see bootup problems (boot crash, boot hang,
1420 spontaneous reboots) or a non-working video driver.
1422 If unsure, say Y.
1424 config ARCH_USES_PG_UNCACHED
1425 def_bool y
1426 depends on X86_PAT
1428 config EFI
1429 bool "EFI runtime service support"
1430 depends on ACPI
1431 ---help---
1432 This enables the kernel to use EFI runtime services that are
1433 available (such as the EFI variable services).
1435 This option is only useful on systems that have EFI firmware.
1436 In addition, you should use the latest ELILO loader available
1437 at <http://elilo.sourceforge.net> in order to take advantage
1438 of EFI runtime services. However, even with this option, the
1439 resultant kernel should continue to boot on existing non-EFI
1440 platforms.
1442 config SECCOMP
1443 def_bool y
1444 prompt "Enable seccomp to safely compute untrusted bytecode"
1445 ---help---
1446 This kernel feature is useful for number crunching applications
1447 that may need to compute untrusted bytecode during their
1448 execution. By using pipes or other transports made available to
1449 the process as file descriptors supporting the read/write
1450 syscalls, it's possible to isolate those applications in
1451 their own address space using seccomp. Once seccomp is
1452 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1453 and the task is only allowed to execute a few safe syscalls
1454 defined by each seccomp mode.
1456 If unsure, say Y. Only embedded should say N here.
1458 config CC_STACKPROTECTOR
1459 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1460 ---help---
1461 This option turns on the -fstack-protector GCC feature. This
1462 feature puts, at the beginning of functions, a canary value on
1463 the stack just before the return address, and validates
1464 the value just before actually returning. Stack based buffer
1465 overflows (that need to overwrite this return address) now also
1466 overwrite the canary, which gets detected and the attack is then
1467 neutralized via a kernel panic.
1469 This feature requires gcc version 4.2 or above, or a distribution
1470 gcc with the feature backported. Older versions are automatically
1471 detected and for those versions, this configuration option is
1472 ignored. (and a warning is printed during bootup)
1474 source kernel/Kconfig.hz
1476 config KEXEC
1477 bool "kexec system call"
1478 ---help---
1479 kexec is a system call that implements the ability to shutdown your
1480 current kernel, and to start another kernel. It is like a reboot
1481 but it is independent of the system firmware. And like a reboot
1482 you can start any kernel with it, not just Linux.
1484 The name comes from the similarity to the exec system call.
1486 It is an ongoing process to be certain the hardware in a machine
1487 is properly shutdown, so do not be surprised if this code does not
1488 initially work for you. It may help to enable device hotplugging
1489 support. As of this writing the exact hardware interface is
1490 strongly in flux, so no good recommendation can be made.
1492 config CRASH_DUMP
1493 bool "kernel crash dumps"
1494 depends on X86_64 || (X86_32 && HIGHMEM)
1495 ---help---
1496 Generate crash dump after being started by kexec.
1497 This should be normally only set in special crash dump kernels
1498 which are loaded in the main kernel with kexec-tools into
1499 a specially reserved region and then later executed after
1500 a crash by kdump/kexec. The crash dump kernel must be compiled
1501 to a memory address not used by the main kernel or BIOS using
1502 PHYSICAL_START, or it must be built as a relocatable image
1503 (CONFIG_RELOCATABLE=y).
1504 For more details see Documentation/kdump/kdump.txt
1506 config KEXEC_JUMP
1507 bool "kexec jump (EXPERIMENTAL)"
1508 depends on EXPERIMENTAL
1509 depends on KEXEC && HIBERNATION
1510 ---help---
1511 Jump between original kernel and kexeced kernel and invoke
1512 code in physical address mode via KEXEC
1514 config PHYSICAL_START
1515 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1516 default "0x1000000"
1517 ---help---
1518 This gives the physical address where the kernel is loaded.
1520 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1521 bzImage will decompress itself to above physical address and
1522 run from there. Otherwise, bzImage will run from the address where
1523 it has been loaded by the boot loader and will ignore above physical
1524 address.
1526 In normal kdump cases one does not have to set/change this option
1527 as now bzImage can be compiled as a completely relocatable image
1528 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1529 address. This option is mainly useful for the folks who don't want
1530 to use a bzImage for capturing the crash dump and want to use a
1531 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1532 to be specifically compiled to run from a specific memory area
1533 (normally a reserved region) and this option comes handy.
1535 So if you are using bzImage for capturing the crash dump,
1536 leave the value here unchanged to 0x1000000 and set
1537 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1538 for capturing the crash dump change this value to start of
1539 the reserved region. In other words, it can be set based on
1540 the "X" value as specified in the "crashkernel=YM@XM"
1541 command line boot parameter passed to the panic-ed
1542 kernel. Please take a look at Documentation/kdump/kdump.txt
1543 for more details about crash dumps.
1545 Usage of bzImage for capturing the crash dump is recommended as
1546 one does not have to build two kernels. Same kernel can be used
1547 as production kernel and capture kernel. Above option should have
1548 gone away after relocatable bzImage support is introduced. But it
1549 is present because there are users out there who continue to use
1550 vmlinux for dump capture. This option should go away down the
1551 line.
1553 Don't change this unless you know what you are doing.
1555 config RELOCATABLE
1556 bool "Build a relocatable kernel"
1557 default y
1558 ---help---
1559 This builds a kernel image that retains relocation information
1560 so it can be loaded someplace besides the default 1MB.
1561 The relocations tend to make the kernel binary about 10% larger,
1562 but are discarded at runtime.
1564 One use is for the kexec on panic case where the recovery kernel
1565 must live at a different physical address than the primary
1566 kernel.
1568 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1569 it has been loaded at and the compile time physical address
1570 (CONFIG_PHYSICAL_START) is ignored.
1572 # Relocation on x86-32 needs some additional build support
1573 config X86_NEED_RELOCS
1574 def_bool y
1575 depends on X86_32 && RELOCATABLE
1577 config PHYSICAL_ALIGN
1578 hex "Alignment value to which kernel should be aligned" if X86_32
1579 default "0x1000000"
1580 range 0x2000 0x1000000
1581 ---help---
1582 This value puts the alignment restrictions on physical address
1583 where kernel is loaded and run from. Kernel is compiled for an
1584 address which meets above alignment restriction.
1586 If bootloader loads the kernel at a non-aligned address and
1587 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1588 address aligned to above value and run from there.
1590 If bootloader loads the kernel at a non-aligned address and
1591 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1592 load address and decompress itself to the address it has been
1593 compiled for and run from there. The address for which kernel is
1594 compiled already meets above alignment restrictions. Hence the
1595 end result is that kernel runs from a physical address meeting
1596 above alignment restrictions.
1598 Don't change this unless you know what you are doing.
1600 config HOTPLUG_CPU
1601 bool "Support for hot-pluggable CPUs"
1602 depends on SMP && HOTPLUG
1603 ---help---
1604 Say Y here to allow turning CPUs off and on. CPUs can be
1605 controlled through /sys/devices/system/cpu.
1606 ( Note: power management support will enable this option
1607 automatically on SMP systems. )
1608 Say N if you want to disable CPU hotplug.
1610 config COMPAT_VDSO
1611 def_bool y
1612 prompt "Compat VDSO support"
1613 depends on X86_32 || IA32_EMULATION
1614 ---help---
1615 Map the 32-bit VDSO to the predictable old-style address too.
1617 Say N here if you are running a sufficiently recent glibc
1618 version (2.3.3 or later), to remove the high-mapped
1619 VDSO mapping and to exclusively use the randomized VDSO.
1621 If unsure, say Y.
1623 config CMDLINE_BOOL
1624 bool "Built-in kernel command line"
1625 ---help---
1626 Allow for specifying boot arguments to the kernel at
1627 build time. On some systems (e.g. embedded ones), it is
1628 necessary or convenient to provide some or all of the
1629 kernel boot arguments with the kernel itself (that is,
1630 to not rely on the boot loader to provide them.)
1632 To compile command line arguments into the kernel,
1633 set this option to 'Y', then fill in the
1634 the boot arguments in CONFIG_CMDLINE.
1636 Systems with fully functional boot loaders (i.e. non-embedded)
1637 should leave this option set to 'N'.
1639 config CMDLINE
1640 string "Built-in kernel command string"
1641 depends on CMDLINE_BOOL
1642 default ""
1643 ---help---
1644 Enter arguments here that should be compiled into the kernel
1645 image and used at boot time. If the boot loader provides a
1646 command line at boot time, it is appended to this string to
1647 form the full kernel command line, when the system boots.
1649 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1650 change this behavior.
1652 In most cases, the command line (whether built-in or provided
1653 by the boot loader) should specify the device for the root
1654 file system.
1656 config CMDLINE_OVERRIDE
1657 bool "Built-in command line overrides boot loader arguments"
1658 depends on CMDLINE_BOOL
1659 ---help---
1660 Set this option to 'Y' to have the kernel ignore the boot loader
1661 command line, and use ONLY the built-in command line.
1663 This is used to work around broken boot loaders. This should
1664 be set to 'N' under normal conditions.
1666 endmenu
1668 config ARCH_ENABLE_MEMORY_HOTPLUG
1669 def_bool y
1670 depends on X86_64 || (X86_32 && HIGHMEM)
1672 config ARCH_ENABLE_MEMORY_HOTREMOVE
1673 def_bool y
1674 depends on MEMORY_HOTPLUG
1676 config HAVE_ARCH_EARLY_PFN_TO_NID
1677 def_bool X86_64
1678 depends on NUMA
1680 config USE_PERCPU_NUMA_NODE_ID
1681 def_bool X86_64
1682 depends on NUMA
1684 menu "Power management and ACPI options"
1686 config ARCH_HIBERNATION_HEADER
1687 def_bool y
1688 depends on X86_64 && HIBERNATION
1690 source "kernel/power/Kconfig"
1692 source "drivers/acpi/Kconfig"
1694 source "drivers/sfi/Kconfig"
1696 config X86_APM_BOOT
1697 def_bool y
1698 depends on APM || APM_MODULE
1700 menuconfig APM
1701 tristate "APM (Advanced Power Management) BIOS support"
1702 depends on X86_32 && PM_SLEEP
1703 ---help---
1704 APM is a BIOS specification for saving power using several different
1705 techniques. This is mostly useful for battery powered laptops with
1706 APM compliant BIOSes. If you say Y here, the system time will be
1707 reset after a RESUME operation, the /proc/apm device will provide
1708 battery status information, and user-space programs will receive
1709 notification of APM "events" (e.g. battery status change).
1711 If you select "Y" here, you can disable actual use of the APM
1712 BIOS by passing the "apm=off" option to the kernel at boot time.
1714 Note that the APM support is almost completely disabled for
1715 machines with more than one CPU.
1717 In order to use APM, you will need supporting software. For location
1718 and more information, read <file:Documentation/power/pm.txt> and the
1719 Battery Powered Linux mini-HOWTO, available from
1720 <http://www.tldp.org/docs.html#howto>.
1722 This driver does not spin down disk drives (see the hdparm(8)
1723 manpage ("man 8 hdparm") for that), and it doesn't turn off
1724 VESA-compliant "green" monitors.
1726 This driver does not support the TI 4000M TravelMate and the ACER
1727 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1728 desktop machines also don't have compliant BIOSes, and this driver
1729 may cause those machines to panic during the boot phase.
1731 Generally, if you don't have a battery in your machine, there isn't
1732 much point in using this driver and you should say N. If you get
1733 random kernel OOPSes or reboots that don't seem to be related to
1734 anything, try disabling/enabling this option (or disabling/enabling
1735 APM in your BIOS).
1737 Some other things you should try when experiencing seemingly random,
1738 "weird" problems:
1740 1) make sure that you have enough swap space and that it is
1741 enabled.
1742 2) pass the "no-hlt" option to the kernel
1743 3) switch on floating point emulation in the kernel and pass
1744 the "no387" option to the kernel
1745 4) pass the "floppy=nodma" option to the kernel
1746 5) pass the "mem=4M" option to the kernel (thereby disabling
1747 all but the first 4 MB of RAM)
1748 6) make sure that the CPU is not over clocked.
1749 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1750 8) disable the cache from your BIOS settings
1751 9) install a fan for the video card or exchange video RAM
1752 10) install a better fan for the CPU
1753 11) exchange RAM chips
1754 12) exchange the motherboard.
1756 To compile this driver as a module, choose M here: the
1757 module will be called apm.
1759 if APM
1761 config APM_IGNORE_USER_SUSPEND
1762 bool "Ignore USER SUSPEND"
1763 ---help---
1764 This option will ignore USER SUSPEND requests. On machines with a
1765 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1766 series notebooks, it is necessary to say Y because of a BIOS bug.
1768 config APM_DO_ENABLE
1769 bool "Enable PM at boot time"
1770 ---help---
1771 Enable APM features at boot time. From page 36 of the APM BIOS
1772 specification: "When disabled, the APM BIOS does not automatically
1773 power manage devices, enter the Standby State, enter the Suspend
1774 State, or take power saving steps in response to CPU Idle calls."
1775 This driver will make CPU Idle calls when Linux is idle (unless this
1776 feature is turned off -- see "Do CPU IDLE calls", below). This
1777 should always save battery power, but more complicated APM features
1778 will be dependent on your BIOS implementation. You may need to turn
1779 this option off if your computer hangs at boot time when using APM
1780 support, or if it beeps continuously instead of suspending. Turn
1781 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1782 T400CDT. This is off by default since most machines do fine without
1783 this feature.
1785 config APM_CPU_IDLE
1786 bool "Make CPU Idle calls when idle"
1787 ---help---
1788 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1789 On some machines, this can activate improved power savings, such as
1790 a slowed CPU clock rate, when the machine is idle. These idle calls
1791 are made after the idle loop has run for some length of time (e.g.,
1792 333 mS). On some machines, this will cause a hang at boot time or
1793 whenever the CPU becomes idle. (On machines with more than one CPU,
1794 this option does nothing.)
1796 config APM_DISPLAY_BLANK
1797 bool "Enable console blanking using APM"
1798 ---help---
1799 Enable console blanking using the APM. Some laptops can use this to
1800 turn off the LCD backlight when the screen blanker of the Linux
1801 virtual console blanks the screen. Note that this is only used by
1802 the virtual console screen blanker, and won't turn off the backlight
1803 when using the X Window system. This also doesn't have anything to
1804 do with your VESA-compliant power-saving monitor. Further, this
1805 option doesn't work for all laptops -- it might not turn off your
1806 backlight at all, or it might print a lot of errors to the console,
1807 especially if you are using gpm.
1809 config APM_ALLOW_INTS
1810 bool "Allow interrupts during APM BIOS calls"
1811 ---help---
1812 Normally we disable external interrupts while we are making calls to
1813 the APM BIOS as a measure to lessen the effects of a badly behaving
1814 BIOS implementation. The BIOS should reenable interrupts if it
1815 needs to. Unfortunately, some BIOSes do not -- especially those in
1816 many of the newer IBM Thinkpads. If you experience hangs when you
1817 suspend, try setting this to Y. Otherwise, say N.
1819 endif # APM
1821 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1823 source "drivers/cpuidle/Kconfig"
1825 source "drivers/idle/Kconfig"
1827 endmenu
1830 menu "Bus options (PCI etc.)"
1832 config PCI
1833 bool "PCI support"
1834 default y
1835 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1836 ---help---
1837 Find out whether you have a PCI motherboard. PCI is the name of a
1838 bus system, i.e. the way the CPU talks to the other stuff inside
1839 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1840 VESA. If you have PCI, say Y, otherwise N.
1842 choice
1843 prompt "PCI access mode"
1844 depends on X86_32 && PCI
1845 default PCI_GOANY
1846 ---help---
1847 On PCI systems, the BIOS can be used to detect the PCI devices and
1848 determine their configuration. However, some old PCI motherboards
1849 have BIOS bugs and may crash if this is done. Also, some embedded
1850 PCI-based systems don't have any BIOS at all. Linux can also try to
1851 detect the PCI hardware directly without using the BIOS.
1853 With this option, you can specify how Linux should detect the
1854 PCI devices. If you choose "BIOS", the BIOS will be used,
1855 if you choose "Direct", the BIOS won't be used, and if you
1856 choose "MMConfig", then PCI Express MMCONFIG will be used.
1857 If you choose "Any", the kernel will try MMCONFIG, then the
1858 direct access method and falls back to the BIOS if that doesn't
1859 work. If unsure, go with the default, which is "Any".
1861 config PCI_GOBIOS
1862 bool "BIOS"
1864 config PCI_GOMMCONFIG
1865 bool "MMConfig"
1867 config PCI_GODIRECT
1868 bool "Direct"
1870 config PCI_GOOLPC
1871 bool "OLPC XO-1"
1872 depends on OLPC
1874 config PCI_GOANY
1875 bool "Any"
1877 endchoice
1879 config PCI_BIOS
1880 def_bool y
1881 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1883 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1884 config PCI_DIRECT
1885 def_bool y
1886 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1888 config PCI_MMCONFIG
1889 def_bool y
1890 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
1892 config PCI_OLPC
1893 def_bool y
1894 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1896 config PCI_XEN
1897 def_bool y
1898 depends on PCI && XEN
1899 select SWIOTLB_XEN
1901 config PCI_DOMAINS
1902 def_bool y
1903 depends on PCI
1905 config PCI_MMCONFIG
1906 bool "Support mmconfig PCI config space access"
1907 depends on X86_64 && PCI && ACPI
1909 config PCI_CNB20LE_QUIRK
1910 bool "Read CNB20LE Host Bridge Windows"
1911 depends on PCI
1912 help
1913 Read the PCI windows out of the CNB20LE host bridge. This allows
1914 PCI hotplug to work on systems with the CNB20LE chipset which do
1915 not have ACPI.
1917 config DMAR
1918 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1919 depends on PCI_MSI && ACPI && EXPERIMENTAL
1920 help
1921 DMA remapping (DMAR) devices support enables independent address
1922 translations for Direct Memory Access (DMA) from devices.
1923 These DMA remapping devices are reported via ACPI tables
1924 and include PCI device scope covered by these DMA
1925 remapping devices.
1927 config DMAR_DEFAULT_ON
1928 def_bool y
1929 prompt "Enable DMA Remapping Devices by default"
1930 depends on DMAR
1931 help
1932 Selecting this option will enable a DMAR device at boot time if
1933 one is found. If this option is not selected, DMAR support can
1934 be enabled by passing intel_iommu=on to the kernel. It is
1935 recommended you say N here while the DMAR code remains
1936 experimental.
1938 config DMAR_BROKEN_GFX_WA
1939 bool "Workaround broken graphics drivers (going away soon)"
1940 depends on DMAR && BROKEN
1941 ---help---
1942 Current Graphics drivers tend to use physical address
1943 for DMA and avoid using DMA APIs. Setting this config
1944 option permits the IOMMU driver to set a unity map for
1945 all the OS-visible memory. Hence the driver can continue
1946 to use physical addresses for DMA, at least until this
1947 option is removed in the 2.6.32 kernel.
1949 config DMAR_FLOPPY_WA
1950 def_bool y
1951 depends on DMAR
1952 ---help---
1953 Floppy disk drivers are known to bypass DMA API calls
1954 thereby failing to work when IOMMU is enabled. This
1955 workaround will setup a 1:1 mapping for the first
1956 16MiB to make floppy (an ISA device) work.
1958 config INTR_REMAP
1959 bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1960 depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
1961 ---help---
1962 Supports Interrupt remapping for IO-APIC and MSI devices.
1963 To use x2apic mode in the CPU's which support x2APIC enhancements or
1964 to support platforms with CPU's having > 8 bit APIC ID, say Y.
1966 source "drivers/pci/pcie/Kconfig"
1968 source "drivers/pci/Kconfig"
1970 # x86_64 have no ISA slots, but do have ISA-style DMA.
1971 config ISA_DMA_API
1972 def_bool y
1974 if X86_32
1976 config ISA
1977 bool "ISA support"
1978 ---help---
1979 Find out whether you have ISA slots on your motherboard. ISA is the
1980 name of a bus system, i.e. the way the CPU talks to the other stuff
1981 inside your box. Other bus systems are PCI, EISA, MicroChannel
1982 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1983 newer boards don't support it. If you have ISA, say Y, otherwise N.
1985 config EISA
1986 bool "EISA support"
1987 depends on ISA
1988 ---help---
1989 The Extended Industry Standard Architecture (EISA) bus was
1990 developed as an open alternative to the IBM MicroChannel bus.
1992 The EISA bus provided some of the features of the IBM MicroChannel
1993 bus while maintaining backward compatibility with cards made for
1994 the older ISA bus. The EISA bus saw limited use between 1988 and
1995 1995 when it was made obsolete by the PCI bus.
1997 Say Y here if you are building a kernel for an EISA-based machine.
1999 Otherwise, say N.
2001 source "drivers/eisa/Kconfig"
2003 config MCA
2004 bool "MCA support"
2005 ---help---
2006 MicroChannel Architecture is found in some IBM PS/2 machines and
2007 laptops. It is a bus system similar to PCI or ISA. See
2008 <file:Documentation/mca.txt> (and especially the web page given
2009 there) before attempting to build an MCA bus kernel.
2011 source "drivers/mca/Kconfig"
2013 config SCx200
2014 tristate "NatSemi SCx200 support"
2015 ---help---
2016 This provides basic support for National Semiconductor's
2017 (now AMD's) Geode processors. The driver probes for the
2018 PCI-IDs of several on-chip devices, so its a good dependency
2019 for other scx200_* drivers.
2021 If compiled as a module, the driver is named scx200.
2023 config SCx200HR_TIMER
2024 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2025 depends on SCx200
2026 default y
2027 ---help---
2028 This driver provides a clocksource built upon the on-chip
2029 27MHz high-resolution timer. Its also a workaround for
2030 NSC Geode SC-1100's buggy TSC, which loses time when the
2031 processor goes idle (as is done by the scheduler). The
2032 other workaround is idle=poll boot option.
2034 config OLPC
2035 bool "One Laptop Per Child support"
2036 select GPIOLIB
2037 select OLPC_OPENFIRMWARE
2038 ---help---
2039 Add support for detecting the unique features of the OLPC
2040 XO hardware.
2042 config OLPC_XO1
2043 tristate "OLPC XO-1 support"
2044 depends on OLPC && PCI
2045 ---help---
2046 Add support for non-essential features of the OLPC XO-1 laptop.
2048 config OLPC_OPENFIRMWARE
2049 bool "Support for OLPC's Open Firmware"
2050 depends on !X86_64 && !X86_PAE
2051 default n
2052 help
2053 This option adds support for the implementation of Open Firmware
2054 that is used on the OLPC XO-1 Children's Machine.
2055 If unsure, say N here.
2057 endif # X86_32
2059 config AMD_NB
2060 def_bool y
2061 depends on CPU_SUP_AMD && PCI
2063 source "drivers/pcmcia/Kconfig"
2065 source "drivers/pci/hotplug/Kconfig"
2067 endmenu
2070 menu "Executable file formats / Emulations"
2072 source "fs/Kconfig.binfmt"
2074 config IA32_EMULATION
2075 bool "IA32 Emulation"
2076 depends on X86_64
2077 select COMPAT_BINFMT_ELF
2078 ---help---
2079 Include code to run 32-bit programs under a 64-bit kernel. You should
2080 likely turn this on, unless you're 100% sure that you don't have any
2081 32-bit programs left.
2083 config IA32_AOUT
2084 tristate "IA32 a.out support"
2085 depends on IA32_EMULATION
2086 ---help---
2087 Support old a.out binaries in the 32bit emulation.
2089 config COMPAT
2090 def_bool y
2091 depends on IA32_EMULATION
2093 config COMPAT_FOR_U64_ALIGNMENT
2094 def_bool COMPAT
2095 depends on X86_64
2097 config SYSVIPC_COMPAT
2098 def_bool y
2099 depends on COMPAT && SYSVIPC
2101 endmenu
2104 config HAVE_ATOMIC_IOMAP
2105 def_bool y
2106 depends on X86_32
2108 config HAVE_TEXT_POKE_SMP
2109 bool
2110 select STOP_MACHINE if SMP
2112 source "net/Kconfig"
2114 source "drivers/Kconfig"
2116 source "drivers/firmware/Kconfig"
2118 source "fs/Kconfig"
2120 source "arch/x86/Kconfig.debug"
2122 source "security/Kconfig"
2124 source "crypto/Kconfig"
2126 source "arch/x86/kvm/Kconfig"
2128 source "lib/Kconfig"