| blob | ff6d4e7d0b3eafd3fdcf84001aaef3a4e1929a52 |
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
11 select CLKSRC_I8253
13 config X86_64
14 def_bool 64BIT
16 ### Arch settings
17 config X86
18 def_bool y
19 select HAVE_AOUT if X86_32
20 select HAVE_UNSTABLE_SCHED_CLOCK
21 select HAVE_IDE
22 select HAVE_OPROFILE
23 select HAVE_PCSPKR_PLATFORM
24 select HAVE_PERF_EVENTS
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_XZ
55 select HAVE_KERNEL_LZO
56 select HAVE_HW_BREAKPOINT
57 select HAVE_MIXED_BREAKPOINTS_REGS
58 select PERF_EVENTS
59 select HAVE_PERF_EVENTS_NMI
60 select ANON_INODES
61 select HAVE_ARCH_KMEMCHECK
62 select HAVE_USER_RETURN_NOTIFIER
63 select HAVE_ARCH_JUMP_LABEL
64 select HAVE_TEXT_POKE_SMP
65 select HAVE_GENERIC_HARDIRQS
66 select HAVE_SPARSE_IRQ
67 select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
68 select GENERIC_FIND_FIRST_BIT
69 select GENERIC_IRQ_PROBE
70 select GENERIC_PENDING_IRQ if SMP
71 select GENERIC_IRQ_SHOW
72 select IRQ_FORCED_THREADING
73 select USE_GENERIC_SMP_HELPERS if SMP
74 select HAVE_BPF_JIT if (X86_64 && NET)
75 select CLKEVT_I8253
76 select ARCH_HAVE_NMI_SAFE_CMPXCHG
78 config INSTRUCTION_DECODER
79 def_bool (KPROBES || PERF_EVENTS)
81 config OUTPUT_FORMAT
82 string
83 default "elf32-i386" if X86_32
84 default "elf64-x86-64" if X86_64
86 config ARCH_DEFCONFIG
87 string
88 default "arch/x86/configs/i386_defconfig" if X86_32
89 default "arch/x86/configs/x86_64_defconfig" if X86_64
91 config GENERIC_CMOS_UPDATE
92 def_bool y
94 config CLOCKSOURCE_WATCHDOG
95 def_bool y
97 config GENERIC_CLOCKEVENTS
98 def_bool y
100 config ARCH_CLOCKSOURCE_DATA
101 def_bool y
102 depends on X86_64
104 config GENERIC_CLOCKEVENTS_BROADCAST
105 def_bool y
106 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
108 config LOCKDEP_SUPPORT
109 def_bool y
111 config STACKTRACE_SUPPORT
112 def_bool y
114 config HAVE_LATENCYTOP_SUPPORT
115 def_bool y
117 config MMU
118 def_bool y
120 config ZONE_DMA
121 bool "DMA memory allocation support" if EXPERT
122 default y
123 help
124 DMA memory allocation support allows devices with less than 32-bit
125 addressing to allocate within the first 16MB of address space.
126 Disable if no such devices will be used.
128 If unsure, say Y.
130 config SBUS
131 bool
133 config NEED_DMA_MAP_STATE
134 def_bool (X86_64 || DMAR || DMA_API_DEBUG)
136 config NEED_SG_DMA_LENGTH
137 def_bool y
139 config GENERIC_ISA_DMA
140 def_bool ISA_DMA_API
142 config GENERIC_IOMAP
143 def_bool y
145 config GENERIC_BUG
146 def_bool y
147 depends on BUG
148 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
150 config GENERIC_BUG_RELATIVE_POINTERS
151 bool
153 config GENERIC_HWEIGHT
154 def_bool y
156 config GENERIC_GPIO
157 bool
159 config ARCH_MAY_HAVE_PC_FDC
160 def_bool ISA_DMA_API
162 config RWSEM_GENERIC_SPINLOCK
163 def_bool !X86_XADD
165 config RWSEM_XCHGADD_ALGORITHM
166 def_bool X86_XADD
168 config ARCH_HAS_CPU_IDLE_WAIT
169 def_bool y
171 config GENERIC_CALIBRATE_DELAY
172 def_bool y
174 config GENERIC_TIME_VSYSCALL
175 bool
176 default X86_64
178 config ARCH_HAS_CPU_RELAX
179 def_bool y
181 config ARCH_HAS_DEFAULT_IDLE
182 def_bool y
184 config ARCH_HAS_CACHE_LINE_SIZE
185 def_bool y
187 config HAVE_SETUP_PER_CPU_AREA
188 def_bool y
190 config NEED_PER_CPU_EMBED_FIRST_CHUNK
191 def_bool y
193 config NEED_PER_CPU_PAGE_FIRST_CHUNK
194 def_bool y
196 config HAVE_CPUMASK_OF_CPU_MAP
197 def_bool X86_64_SMP
199 config ARCH_HIBERNATION_POSSIBLE
200 def_bool y
202 config ARCH_SUSPEND_POSSIBLE
203 def_bool y
205 config ZONE_DMA32
206 bool
207 default X86_64
209 config ARCH_POPULATES_NODE_MAP
210 def_bool y
212 config AUDIT_ARCH
213 bool
214 default X86_64
216 config ARCH_SUPPORTS_OPTIMIZED_INLINING
217 def_bool y
219 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
220 def_bool y
222 config HAVE_INTEL_TXT
223 def_bool y
224 depends on EXPERIMENTAL && DMAR && ACPI
226 config X86_32_SMP
227 def_bool y
228 depends on X86_32 && SMP
230 config X86_64_SMP
231 def_bool y
232 depends on X86_64 && SMP
234 config X86_HT
235 def_bool y
236 depends on SMP
238 config X86_32_LAZY_GS
239 def_bool y
240 depends on X86_32 && !CC_STACKPROTECTOR
242 config ARCH_HWEIGHT_CFLAGS
243 string
244 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
245 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
247 config KTIME_SCALAR
248 def_bool X86_32
250 config ARCH_CPU_PROBE_RELEASE
251 def_bool y
252 depends on HOTPLUG_CPU
254 source "init/Kconfig"
255 source "kernel/Kconfig.freezer"
257 menu "Processor type and features"
259 source "kernel/time/Kconfig"
261 config SMP
262 bool "Symmetric multi-processing support"
263 ---help---
264 This enables support for systems with more than one CPU. If you have
265 a system with only one CPU, like most personal computers, say N. If
266 you have a system with more than one CPU, say Y.
268 If you say N here, the kernel will run on single and multiprocessor
269 machines, but will use only one CPU of a multiprocessor machine. If
270 you say Y here, the kernel will run on many, but not all,
271 singleprocessor machines. On a singleprocessor machine, the kernel
272 will run faster if you say N here.
274 Note that if you say Y here and choose architecture "586" or
275 "Pentium" under "Processor family", the kernel will not work on 486
276 architectures. Similarly, multiprocessor kernels for the "PPro"
277 architecture may not work on all Pentium based boards.
279 People using multiprocessor machines who say Y here should also say
280 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
281 Management" code will be disabled if you say Y here.
283 See also <file:Documentation/i386/IO-APIC.txt>,
284 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
285 <http://www.tldp.org/docs.html#howto>.
287 If you don't know what to do here, say N.
289 config X86_X2APIC
290 bool "Support x2apic"
291 depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
292 ---help---
293 This enables x2apic support on CPUs that have this feature.
295 This allows 32-bit apic IDs (so it can support very large systems),
296 and accesses the local apic via MSRs not via mmio.
298 If you don't know what to do here, say N.
300 config X86_MPPARSE
301 bool "Enable MPS table" if ACPI
302 default y
303 depends on X86_LOCAL_APIC
304 ---help---
305 For old smp systems that do not have proper acpi support. Newer systems
306 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
308 config X86_BIGSMP
309 bool "Support for big SMP systems with more than 8 CPUs"
310 depends on X86_32 && SMP
311 ---help---
312 This option is needed for the systems that have more than 8 CPUs
314 if X86_32
315 config X86_EXTENDED_PLATFORM
316 bool "Support for extended (non-PC) x86 platforms"
317 default y
318 ---help---
319 If you disable this option then the kernel will only support
320 standard PC platforms. (which covers the vast majority of
321 systems out there.)
323 If you enable this option then you'll be able to select support
324 for the following (non-PC) 32 bit x86 platforms:
325 AMD Elan
326 NUMAQ (IBM/Sequent)
327 RDC R-321x SoC
328 SGI 320/540 (Visual Workstation)
329 Summit/EXA (IBM x440)
330 Unisys ES7000 IA32 series
331 Moorestown MID devices
333 If you have one of these systems, or if you want to build a
334 generic distribution kernel, say Y here - otherwise say N.
335 endif
337 if X86_64
338 config X86_EXTENDED_PLATFORM
339 bool "Support for extended (non-PC) x86 platforms"
340 default y
341 ---help---
342 If you disable this option then the kernel will only support
343 standard PC platforms. (which covers the vast majority of
344 systems out there.)
346 If you enable this option then you'll be able to select support
347 for the following (non-PC) 64 bit x86 platforms:
348 ScaleMP vSMP
349 SGI Ultraviolet
351 If you have one of these systems, or if you want to build a
352 generic distribution kernel, say Y here - otherwise say N.
353 endif
354 # This is an alphabetically sorted list of 64 bit extended platforms
355 # Please maintain the alphabetic order if and when there are additions
357 config X86_VSMP
358 bool "ScaleMP vSMP"
359 select PARAVIRT_GUEST
360 select PARAVIRT
361 depends on X86_64 && PCI
362 depends on X86_EXTENDED_PLATFORM
363 ---help---
364 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
365 supposed to run on these EM64T-based machines. Only choose this option
366 if you have one of these machines.
368 config X86_UV
369 bool "SGI Ultraviolet"
370 depends on X86_64
371 depends on X86_EXTENDED_PLATFORM
372 depends on NUMA
373 depends on X86_X2APIC
374 ---help---
375 This option is needed in order to support SGI Ultraviolet systems.
376 If you don't have one of these, you should say N here.
378 # Following is an alphabetically sorted list of 32 bit extended platforms
379 # Please maintain the alphabetic order if and when there are additions
381 config X86_INTEL_CE
382 bool "CE4100 TV platform"
383 depends on PCI
384 depends on PCI_GODIRECT
385 depends on X86_32
386 depends on X86_EXTENDED_PLATFORM
387 select X86_REBOOTFIXUPS
388 select OF
389 select OF_EARLY_FLATTREE
390 ---help---
391 Select for the Intel CE media processor (CE4100) SOC.
392 This option compiles in support for the CE4100 SOC for settop
393 boxes and media devices.
395 config X86_INTEL_MID
396 bool "Intel MID platform support"
397 depends on X86_32
398 depends on X86_EXTENDED_PLATFORM
399 ---help---
400 Select to build a kernel capable of supporting Intel MID platform
401 systems which do not have the PCI legacy interfaces (Moorestown,
402 Medfield). If you are building for a PC class system say N here.
404 if X86_INTEL_MID
406 config X86_MRST
407 bool "Moorestown MID platform"
408 depends on PCI
409 depends on PCI_GOANY
410 depends on X86_IO_APIC
411 select APB_TIMER
412 select I2C
413 select SPI
414 select INTEL_SCU_IPC
415 select X86_PLATFORM_DEVICES
416 ---help---
417 Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
418 Internet Device(MID) platform. Moorestown consists of two chips:
419 Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
420 Unlike standard x86 PCs, Moorestown does not have many legacy devices
421 nor standard legacy replacement devices/features. e.g. Moorestown does
422 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
424 endif
426 config X86_RDC321X
427 bool "RDC R-321x SoC"
428 depends on X86_32
429 depends on X86_EXTENDED_PLATFORM
430 select M486
431 select X86_REBOOTFIXUPS
432 ---help---
433 This option is needed for RDC R-321x system-on-chip, also known
434 as R-8610-(G).
435 If you don't have one of these chips, you should say N here.
437 config X86_32_NON_STANDARD
438 bool "Support non-standard 32-bit SMP architectures"
439 depends on X86_32 && SMP
440 depends on X86_EXTENDED_PLATFORM
441 ---help---
442 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
443 subarchitectures. It is intended for a generic binary kernel.
444 if you select them all, kernel will probe it one by one. and will
445 fallback to default.
447 # Alphabetically sorted list of Non standard 32 bit platforms
449 config X86_NUMAQ
450 bool "NUMAQ (IBM/Sequent)"
451 depends on X86_32_NON_STANDARD
452 depends on PCI
453 select NUMA
454 select X86_MPPARSE
455 ---help---
456 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
457 NUMA multiquad box. This changes the way that processors are
458 bootstrapped, and uses Clustered Logical APIC addressing mode instead
459 of Flat Logical. You will need a new lynxer.elf file to flash your
460 firmware with - send email to <Martin.Bligh@us.ibm.com>.
462 config X86_SUPPORTS_MEMORY_FAILURE
463 def_bool y
464 # MCE code calls memory_failure():
465 depends on X86_MCE
466 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
467 depends on !X86_NUMAQ
468 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
469 depends on X86_64 || !SPARSEMEM
470 select ARCH_SUPPORTS_MEMORY_FAILURE
472 config X86_VISWS
473 bool "SGI 320/540 (Visual Workstation)"
474 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
475 depends on X86_32_NON_STANDARD
476 ---help---
477 The SGI Visual Workstation series is an IA32-based workstation
478 based on SGI systems chips with some legacy PC hardware attached.
480 Say Y here to create a kernel to run on the SGI 320 or 540.
482 A kernel compiled for the Visual Workstation will run on general
483 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
485 config X86_SUMMIT
486 bool "Summit/EXA (IBM x440)"
487 depends on X86_32_NON_STANDARD
488 ---help---
489 This option is needed for IBM systems that use the Summit/EXA chipset.
490 In particular, it is needed for the x440.
492 config X86_ES7000
493 bool "Unisys ES7000 IA32 series"
494 depends on X86_32_NON_STANDARD && X86_BIGSMP
495 ---help---
496 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
497 supposed to run on an IA32-based Unisys ES7000 system.
499 config X86_32_IRIS
500 tristate "Eurobraille/Iris poweroff module"
501 depends on X86_32
502 ---help---
503 The Iris machines from EuroBraille do not have APM or ACPI support
504 to shut themselves down properly. A special I/O sequence is
505 needed to do so, which is what this module does at
506 kernel shutdown.
508 This is only for Iris machines from EuroBraille.
510 If unused, say N.
512 config SCHED_OMIT_FRAME_POINTER
513 def_bool y
514 prompt "Single-depth WCHAN output"
515 depends on X86
516 ---help---
517 Calculate simpler /proc/<PID>/wchan values. If this option
518 is disabled then wchan values will recurse back to the
519 caller function. This provides more accurate wchan values,
520 at the expense of slightly more scheduling overhead.
522 If in doubt, say "Y".
524 menuconfig PARAVIRT_GUEST
525 bool "Paravirtualized guest support"
526 ---help---
527 Say Y here to get to see options related to running Linux under
528 various hypervisors. This option alone does not add any kernel code.
530 If you say N, all options in this submenu will be skipped and disabled.
532 if PARAVIRT_GUEST
534 config PARAVIRT_TIME_ACCOUNTING
535 bool "Paravirtual steal time accounting"
536 select PARAVIRT
537 default n
538 ---help---
539 Select this option to enable fine granularity task steal time
540 accounting. Time spent executing other tasks in parallel with
541 the current vCPU is discounted from the vCPU power. To account for
542 that, there can be a small performance impact.
544 If in doubt, say N here.
546 source "arch/x86/xen/Kconfig"
548 config KVM_CLOCK
549 bool "KVM paravirtualized clock"
550 select PARAVIRT
551 select PARAVIRT_CLOCK
552 ---help---
553 Turning on this option will allow you to run a paravirtualized clock
554 when running over the KVM hypervisor. Instead of relying on a PIT
555 (or probably other) emulation by the underlying device model, the host
556 provides the guest with timing infrastructure such as time of day, and
557 system time
559 config KVM_GUEST
560 bool "KVM Guest support"
561 select PARAVIRT
562 ---help---
563 This option enables various optimizations for running under the KVM
564 hypervisor.
566 source "arch/x86/lguest/Kconfig"
568 config PARAVIRT
569 bool "Enable paravirtualization code"
570 ---help---
571 This changes the kernel so it can modify itself when it is run
572 under a hypervisor, potentially improving performance significantly
573 over full virtualization. However, when run without a hypervisor
574 the kernel is theoretically slower and slightly larger.
576 config PARAVIRT_SPINLOCKS
577 bool "Paravirtualization layer for spinlocks"
578 depends on PARAVIRT && SMP && EXPERIMENTAL
579 ---help---
580 Paravirtualized spinlocks allow a pvops backend to replace the
581 spinlock implementation with something virtualization-friendly
582 (for example, block the virtual CPU rather than spinning).
584 Unfortunately the downside is an up to 5% performance hit on
585 native kernels, with various workloads.
587 If you are unsure how to answer this question, answer N.
589 config PARAVIRT_CLOCK
590 bool
592 endif
594 config PARAVIRT_DEBUG
595 bool "paravirt-ops debugging"
596 depends on PARAVIRT && DEBUG_KERNEL
597 ---help---
598 Enable to debug paravirt_ops internals. Specifically, BUG if
599 a paravirt_op is missing when it is called.
601 config NO_BOOTMEM
602 def_bool y
604 config MEMTEST
605 bool "Memtest"
606 ---help---
607 This option adds a kernel parameter 'memtest', which allows memtest
608 to be set.
609 memtest=0, mean disabled; -- default
610 memtest=1, mean do 1 test pattern;
611 ...
612 memtest=4, mean do 4 test patterns.
613 If you are unsure how to answer this question, answer N.
615 config X86_SUMMIT_NUMA
616 def_bool y
617 depends on X86_32 && NUMA && X86_32_NON_STANDARD
619 config X86_CYCLONE_TIMER
620 def_bool y
621 depends on X86_32_NON_STANDARD
623 source "arch/x86/Kconfig.cpu"
625 config HPET_TIMER
626 def_bool X86_64
627 prompt "HPET Timer Support" if X86_32
628 ---help---
629 Use the IA-PC HPET (High Precision Event Timer) to manage
630 time in preference to the PIT and RTC, if a HPET is
631 present.
632 HPET is the next generation timer replacing legacy 8254s.
633 The HPET provides a stable time base on SMP
634 systems, unlike the TSC, but it is more expensive to access,
635 as it is off-chip. You can find the HPET spec at
636 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
638 You can safely choose Y here. However, HPET will only be
639 activated if the platform and the BIOS support this feature.
640 Otherwise the 8254 will be used for timing services.
642 Choose N to continue using the legacy 8254 timer.
644 config HPET_EMULATE_RTC
645 def_bool y
646 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
648 config APB_TIMER
649 def_bool y if MRST
650 prompt "Langwell APB Timer Support" if X86_MRST
651 select DW_APB_TIMER
652 help
653 APB timer is the replacement for 8254, HPET on X86 MID platforms.
654 The APBT provides a stable time base on SMP
655 systems, unlike the TSC, but it is more expensive to access,
656 as it is off-chip. APB timers are always running regardless of CPU
657 C states, they are used as per CPU clockevent device when possible.
659 # Mark as expert because too many people got it wrong.
660 # The code disables itself when not needed.
661 config DMI
662 default y
663 bool "Enable DMI scanning" if EXPERT
664 ---help---
665 Enabled scanning of DMI to identify machine quirks. Say Y
666 here unless you have verified that your setup is not
667 affected by entries in the DMI blacklist. Required by PNP
668 BIOS code.
670 config GART_IOMMU
671 bool "GART IOMMU support" if EXPERT
672 default y
673 select SWIOTLB
674 depends on X86_64 && PCI && AMD_NB
675 ---help---
676 Support for full DMA access of devices with 32bit memory access only
677 on systems with more than 3GB. This is usually needed for USB,
678 sound, many IDE/SATA chipsets and some other devices.
679 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
680 based hardware IOMMU and a software bounce buffer based IOMMU used
681 on Intel systems and as fallback.
682 The code is only active when needed (enough memory and limited
683 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
684 too.
686 config CALGARY_IOMMU
687 bool "IBM Calgary IOMMU support"
688 select SWIOTLB
689 depends on X86_64 && PCI && EXPERIMENTAL
690 ---help---
691 Support for hardware IOMMUs in IBM's xSeries x366 and x460
692 systems. Needed to run systems with more than 3GB of memory
693 properly with 32-bit PCI devices that do not support DAC
694 (Double Address Cycle). Calgary also supports bus level
695 isolation, where all DMAs pass through the IOMMU. This
696 prevents them from going anywhere except their intended
697 destination. This catches hard-to-find kernel bugs and
698 mis-behaving drivers and devices that do not use the DMA-API
699 properly to set up their DMA buffers. The IOMMU can be
700 turned off at boot time with the iommu=off parameter.
701 Normally the kernel will make the right choice by itself.
702 If unsure, say Y.
704 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
705 def_bool y
706 prompt "Should Calgary be enabled by default?"
707 depends on CALGARY_IOMMU
708 ---help---
709 Should Calgary be enabled by default? if you choose 'y', Calgary
710 will be used (if it exists). If you choose 'n', Calgary will not be
711 used even if it exists. If you choose 'n' and would like to use
712 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
713 If unsure, say Y.
715 # need this always selected by IOMMU for the VIA workaround
716 config SWIOTLB
717 def_bool y if X86_64
718 ---help---
719 Support for software bounce buffers used on x86-64 systems
720 which don't have a hardware IOMMU (e.g. the current generation
721 of Intel's x86-64 CPUs). Using this PCI devices which can only
722 access 32-bits of memory can be used on systems with more than
723 3 GB of memory. If unsure, say Y.
725 config IOMMU_HELPER
726 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
728 config MAXSMP
729 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
730 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
731 select CPUMASK_OFFSTACK
732 ---help---
733 Enable maximum number of CPUS and NUMA Nodes for this architecture.
734 If unsure, say N.
736 config NR_CPUS
737 int "Maximum number of CPUs" if SMP && !MAXSMP
738 range 2 8 if SMP && X86_32 && !X86_BIGSMP
739 range 2 512 if SMP && !MAXSMP
740 default "1" if !SMP
741 default "4096" if MAXSMP
742 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
743 default "8" if SMP
744 ---help---
745 This allows you to specify the maximum number of CPUs which this
746 kernel will support. The maximum supported value is 512 and the
747 minimum value which makes sense is 2.
749 This is purely to save memory - each supported CPU adds
750 approximately eight kilobytes to the kernel image.
752 config SCHED_SMT
753 bool "SMT (Hyperthreading) scheduler support"
754 depends on X86_HT
755 ---help---
756 SMT scheduler support improves the CPU scheduler's decision making
757 when dealing with Intel Pentium 4 chips with HyperThreading at a
758 cost of slightly increased overhead in some places. If unsure say
759 N here.
761 config SCHED_MC
762 def_bool y
763 prompt "Multi-core scheduler support"
764 depends on X86_HT
765 ---help---
766 Multi-core scheduler support improves the CPU scheduler's decision
767 making when dealing with multi-core CPU chips at a cost of slightly
768 increased overhead in some places. If unsure say N here.
770 config IRQ_TIME_ACCOUNTING
771 bool "Fine granularity task level IRQ time accounting"
772 default n
773 ---help---
774 Select this option to enable fine granularity task irq time
775 accounting. This is done by reading a timestamp on each
776 transitions between softirq and hardirq state, so there can be a
777 small performance impact.
779 If in doubt, say N here.
781 source "kernel/Kconfig.preempt"
783 config X86_UP_APIC
784 bool "Local APIC support on uniprocessors"
785 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
786 ---help---
787 A local APIC (Advanced Programmable Interrupt Controller) is an
788 integrated interrupt controller in the CPU. If you have a single-CPU
789 system which has a processor with a local APIC, you can say Y here to
790 enable and use it. If you say Y here even though your machine doesn't
791 have a local APIC, then the kernel will still run with no slowdown at
792 all. The local APIC supports CPU-generated self-interrupts (timer,
793 performance counters), and the NMI watchdog which detects hard
794 lockups.
796 config X86_UP_IOAPIC
797 bool "IO-APIC support on uniprocessors"
798 depends on X86_UP_APIC
799 ---help---
800 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
801 SMP-capable replacement for PC-style interrupt controllers. Most
802 SMP systems and many recent uniprocessor systems have one.
804 If you have a single-CPU system with an IO-APIC, you can say Y here
805 to use it. If you say Y here even though your machine doesn't have
806 an IO-APIC, then the kernel will still run with no slowdown at all.
808 config X86_LOCAL_APIC
809 def_bool y
810 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
812 config X86_IO_APIC
813 def_bool y
814 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC
816 config X86_VISWS_APIC
817 def_bool y
818 depends on X86_32 && X86_VISWS
820 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
821 bool "Reroute for broken boot IRQs"
822 depends on X86_IO_APIC
823 ---help---
824 This option enables a workaround that fixes a source of
825 spurious interrupts. This is recommended when threaded
826 interrupt handling is used on systems where the generation of
827 superfluous "boot interrupts" cannot be disabled.
829 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
830 entry in the chipset's IO-APIC is masked (as, e.g. the RT
831 kernel does during interrupt handling). On chipsets where this
832 boot IRQ generation cannot be disabled, this workaround keeps
833 the original IRQ line masked so that only the equivalent "boot
834 IRQ" is delivered to the CPUs. The workaround also tells the
835 kernel to set up the IRQ handler on the boot IRQ line. In this
836 way only one interrupt is delivered to the kernel. Otherwise
837 the spurious second interrupt may cause the kernel to bring
838 down (vital) interrupt lines.
840 Only affects "broken" chipsets. Interrupt sharing may be
841 increased on these systems.
843 config X86_MCE
844 bool "Machine Check / overheating reporting"
845 ---help---
846 Machine Check support allows the processor to notify the
847 kernel if it detects a problem (e.g. overheating, data corruption).
848 The action the kernel takes depends on the severity of the problem,
849 ranging from warning messages to halting the machine.
851 config X86_MCE_INTEL
852 def_bool y
853 prompt "Intel MCE features"
854 depends on X86_MCE && X86_LOCAL_APIC
855 ---help---
856 Additional support for intel specific MCE features such as
857 the thermal monitor.
859 config X86_MCE_AMD
860 def_bool y
861 prompt "AMD MCE features"
862 depends on X86_MCE && X86_LOCAL_APIC
863 ---help---
864 Additional support for AMD specific MCE features such as
865 the DRAM Error Threshold.
867 config X86_ANCIENT_MCE
868 bool "Support for old Pentium 5 / WinChip machine checks"
869 depends on X86_32 && X86_MCE
870 ---help---
871 Include support for machine check handling on old Pentium 5 or WinChip
872 systems. These typically need to be enabled explicitely on the command
873 line.
875 config X86_MCE_THRESHOLD
876 depends on X86_MCE_AMD || X86_MCE_INTEL
877 def_bool y
879 config X86_MCE_INJECT
880 depends on X86_MCE
881 tristate "Machine check injector support"
882 ---help---
883 Provide support for injecting machine checks for testing purposes.
884 If you don't know what a machine check is and you don't do kernel
885 QA it is safe to say n.
887 config X86_THERMAL_VECTOR
888 def_bool y
889 depends on X86_MCE_INTEL
891 config VM86
892 bool "Enable VM86 support" if EXPERT
893 default y
894 depends on X86_32
895 ---help---
896 This option is required by programs like DOSEMU to run 16-bit legacy
897 code on X86 processors. It also may be needed by software like
898 XFree86 to initialize some video cards via BIOS. Disabling this
899 option saves about 6k.
901 config TOSHIBA
902 tristate "Toshiba Laptop support"
903 depends on X86_32
904 ---help---
905 This adds a driver to safely access the System Management Mode of
906 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
907 not work on models with a Phoenix BIOS. The System Management Mode
908 is used to set the BIOS and power saving options on Toshiba portables.
910 For information on utilities to make use of this driver see the
911 Toshiba Linux utilities web site at:
912 <http://www.buzzard.org.uk/toshiba/>.
914 Say Y if you intend to run this kernel on a Toshiba portable.
915 Say N otherwise.
917 config I8K
918 tristate "Dell laptop support"
919 select HWMON
920 ---help---
921 This adds a driver to safely access the System Management Mode
922 of the CPU on the Dell Inspiron 8000. The System Management Mode
923 is used to read cpu temperature and cooling fan status and to
924 control the fans on the I8K portables.
926 This driver has been tested only on the Inspiron 8000 but it may
927 also work with other Dell laptops. You can force loading on other
928 models by passing the parameter `force=1' to the module. Use at
929 your own risk.
931 For information on utilities to make use of this driver see the
932 I8K Linux utilities web site at:
933 <http://people.debian.org/~dz/i8k/>
935 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
936 Say N otherwise.
938 config X86_REBOOTFIXUPS
939 bool "Enable X86 board specific fixups for reboot"
940 depends on X86_32
941 ---help---
942 This enables chipset and/or board specific fixups to be done
943 in order to get reboot to work correctly. This is only needed on
944 some combinations of hardware and BIOS. The symptom, for which
945 this config is intended, is when reboot ends with a stalled/hung
946 system.
948 Currently, the only fixup is for the Geode machines using
949 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
951 Say Y if you want to enable the fixup. Currently, it's safe to
952 enable this option even if you don't need it.
953 Say N otherwise.
955 config MICROCODE
956 tristate "/dev/cpu/microcode - microcode support"
957 select FW_LOADER
958 ---help---
959 If you say Y here, you will be able to update the microcode on
960 certain Intel and AMD processors. The Intel support is for the
961 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
962 Pentium 4, Xeon etc. The AMD support is for family 0x10 and
963 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
964 You will obviously need the actual microcode binary data itself
965 which is not shipped with the Linux kernel.
967 This option selects the general module only, you need to select
968 at least one vendor specific module as well.
970 To compile this driver as a module, choose M here: the
971 module will be called microcode.
973 config MICROCODE_INTEL
974 bool "Intel microcode patch loading support"
975 depends on MICROCODE
976 default MICROCODE
977 select FW_LOADER
978 ---help---
979 This options enables microcode patch loading support for Intel
980 processors.
982 For latest news and information on obtaining all the required
983 Intel ingredients for this driver, check:
984 <http://www.urbanmyth.org/microcode/>.
986 config MICROCODE_AMD
987 bool "AMD microcode patch loading support"
988 depends on MICROCODE
989 select FW_LOADER
990 ---help---
991 If you select this option, microcode patch loading support for AMD
992 processors will be enabled.
994 config MICROCODE_OLD_INTERFACE
995 def_bool y
996 depends on MICROCODE
998 config X86_MSR
999 tristate "/dev/cpu/*/msr - Model-specific register support"
1000 ---help---
1001 This device gives privileged processes access to the x86
1002 Model-Specific Registers (MSRs). It is a character device with
1003 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1004 MSR accesses are directed to a specific CPU on multi-processor
1005 systems.
1007 config X86_CPUID
1008 tristate "/dev/cpu/*/cpuid - CPU information support"
1009 ---help---
1010 This device gives processes access to the x86 CPUID instruction to
1011 be executed on a specific processor. It is a character device
1012 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1013 /dev/cpu/31/cpuid.
1015 choice
1016 prompt "High Memory Support"
1017 default HIGHMEM64G if X86_NUMAQ
1018 default HIGHMEM4G
1019 depends on X86_32
1021 config NOHIGHMEM
1022 bool "off"
1023 depends on !X86_NUMAQ
1024 ---help---
1025 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1026 However, the address space of 32-bit x86 processors is only 4
1027 Gigabytes large. That means that, if you have a large amount of
1028 physical memory, not all of it can be "permanently mapped" by the
1029 kernel. The physical memory that's not permanently mapped is called
1030 "high memory".
1032 If you are compiling a kernel which will never run on a machine with
1033 more than 1 Gigabyte total physical RAM, answer "off" here (default
1034 choice and suitable for most users). This will result in a "3GB/1GB"
1035 split: 3GB are mapped so that each process sees a 3GB virtual memory
1036 space and the remaining part of the 4GB virtual memory space is used
1037 by the kernel to permanently map as much physical memory as
1038 possible.
1040 If the machine has between 1 and 4 Gigabytes physical RAM, then
1041 answer "4GB" here.
1043 If more than 4 Gigabytes is used then answer "64GB" here. This
1044 selection turns Intel PAE (Physical Address Extension) mode on.
1045 PAE implements 3-level paging on IA32 processors. PAE is fully
1046 supported by Linux, PAE mode is implemented on all recent Intel
1047 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1048 then the kernel will not boot on CPUs that don't support PAE!
1050 The actual amount of total physical memory will either be
1051 auto detected or can be forced by using a kernel command line option
1052 such as "mem=256M". (Try "man bootparam" or see the documentation of
1053 your boot loader (lilo or loadlin) about how to pass options to the
1054 kernel at boot time.)
1056 If unsure, say "off".
1058 config HIGHMEM4G
1059 bool "4GB"
1060 depends on !X86_NUMAQ
1061 ---help---
1062 Select this if you have a 32-bit processor and between 1 and 4
1063 gigabytes of physical RAM.
1065 config HIGHMEM64G
1066 bool "64GB"
1067 depends on !M386 && !M486
1068 select X86_PAE
1069 ---help---
1070 Select this if you have a 32-bit processor and more than 4
1071 gigabytes of physical RAM.
1073 endchoice
1075 choice
1076 depends on EXPERIMENTAL
1077 prompt "Memory split" if EXPERT
1078 default VMSPLIT_3G
1079 depends on X86_32
1080 ---help---
1081 Select the desired split between kernel and user memory.
1083 If the address range available to the kernel is less than the
1084 physical memory installed, the remaining memory will be available
1085 as "high memory". Accessing high memory is a little more costly
1086 than low memory, as it needs to be mapped into the kernel first.
1087 Note that increasing the kernel address space limits the range
1088 available to user programs, making the address space there
1089 tighter. Selecting anything other than the default 3G/1G split
1090 will also likely make your kernel incompatible with binary-only
1091 kernel modules.
1093 If you are not absolutely sure what you are doing, leave this
1094 option alone!
1096 config VMSPLIT_3G
1097 bool "3G/1G user/kernel split"
1098 config VMSPLIT_3G_OPT
1099 depends on !X86_PAE
1100 bool "3G/1G user/kernel split (for full 1G low memory)"
1101 config VMSPLIT_2G
1102 bool "2G/2G user/kernel split"
1103 config VMSPLIT_2G_OPT
1104 depends on !X86_PAE
1105 bool "2G/2G user/kernel split (for full 2G low memory)"
1106 config VMSPLIT_1G
1107 bool "1G/3G user/kernel split"
1108 endchoice
1110 config PAGE_OFFSET
1111 hex
1112 default 0xB0000000 if VMSPLIT_3G_OPT
1113 default 0x80000000 if VMSPLIT_2G
1114 default 0x78000000 if VMSPLIT_2G_OPT
1115 default 0x40000000 if VMSPLIT_1G
1116 default 0xC0000000
1117 depends on X86_32
1119 config HIGHMEM
1120 def_bool y
1121 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1123 config X86_PAE
1124 bool "PAE (Physical Address Extension) Support"
1125 depends on X86_32 && !HIGHMEM4G
1126 ---help---
1127 PAE is required for NX support, and furthermore enables
1128 larger swapspace support for non-overcommit purposes. It
1129 has the cost of more pagetable lookup overhead, and also
1130 consumes more pagetable space per process.
1132 config ARCH_PHYS_ADDR_T_64BIT
1133 def_bool X86_64 || X86_PAE
1135 config ARCH_DMA_ADDR_T_64BIT
1136 def_bool X86_64 || HIGHMEM64G
1138 config DIRECT_GBPAGES
1139 bool "Enable 1GB pages for kernel pagetables" if EXPERT
1140 default y
1141 depends on X86_64
1142 ---help---
1143 Allow the kernel linear mapping to use 1GB pages on CPUs that
1144 support it. This can improve the kernel's performance a tiny bit by
1145 reducing TLB pressure. If in doubt, say "Y".
1147 # Common NUMA Features
1148 config NUMA
1149 bool "Numa Memory Allocation and Scheduler Support"
1150 depends on SMP
1151 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1152 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1153 ---help---
1154 Enable NUMA (Non Uniform Memory Access) support.
1156 The kernel will try to allocate memory used by a CPU on the
1157 local memory controller of the CPU and add some more
1158 NUMA awareness to the kernel.
1160 For 64-bit this is recommended if the system is Intel Core i7
1161 (or later), AMD Opteron, or EM64T NUMA.
1163 For 32-bit this is only needed on (rare) 32-bit-only platforms
1164 that support NUMA topologies, such as NUMAQ / Summit, or if you
1165 boot a 32-bit kernel on a 64-bit NUMA platform.
1167 Otherwise, you should say N.
1169 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1170 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1172 config AMD_NUMA
1173 def_bool y
1174 prompt "Old style AMD Opteron NUMA detection"
1175 depends on X86_64 && NUMA && PCI
1176 ---help---
1177 Enable AMD NUMA node topology detection. You should say Y here if
1178 you have a multi processor AMD system. This uses an old method to
1179 read the NUMA configuration directly from the builtin Northbridge
1180 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1181 which also takes priority if both are compiled in.
1183 config X86_64_ACPI_NUMA
1184 def_bool y
1185 prompt "ACPI NUMA detection"
1186 depends on X86_64 && NUMA && ACPI && PCI
1187 select ACPI_NUMA
1188 ---help---
1189 Enable ACPI SRAT based node topology detection.
1191 # Some NUMA nodes have memory ranges that span
1192 # other nodes. Even though a pfn is valid and
1193 # between a node's start and end pfns, it may not
1194 # reside on that node. See memmap_init_zone()
1195 # for details.
1196 config NODES_SPAN_OTHER_NODES
1197 def_bool y
1198 depends on X86_64_ACPI_NUMA
1200 config NUMA_EMU
1201 bool "NUMA emulation"
1202 depends on NUMA
1203 ---help---
1204 Enable NUMA emulation. A flat machine will be split
1205 into virtual nodes when booted with "numa=fake=N", where N is the
1206 number of nodes. This is only useful for debugging.
1208 config NODES_SHIFT
1209 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1210 range 1 10
1211 default "10" if MAXSMP
1212 default "6" if X86_64
1213 default "4" if X86_NUMAQ
1214 default "3"
1215 depends on NEED_MULTIPLE_NODES
1216 ---help---
1217 Specify the maximum number of NUMA Nodes available on the target
1218 system. Increases memory reserved to accommodate various tables.
1220 config HAVE_ARCH_BOOTMEM
1221 def_bool y
1222 depends on X86_32 && NUMA
1224 config HAVE_ARCH_ALLOC_REMAP
1225 def_bool y
1226 depends on X86_32 && NUMA
1228 config ARCH_HAVE_MEMORY_PRESENT
1229 def_bool y
1230 depends on X86_32 && DISCONTIGMEM
1232 config NEED_NODE_MEMMAP_SIZE
1233 def_bool y
1234 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1236 config ARCH_FLATMEM_ENABLE
1237 def_bool y
1238 depends on X86_32 && !NUMA
1240 config ARCH_DISCONTIGMEM_ENABLE
1241 def_bool y
1242 depends on NUMA && X86_32
1244 config ARCH_DISCONTIGMEM_DEFAULT
1245 def_bool y
1246 depends on NUMA && X86_32
1248 config ARCH_SPARSEMEM_ENABLE
1249 def_bool y
1250 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1251 select SPARSEMEM_STATIC if X86_32
1252 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1254 config ARCH_SPARSEMEM_DEFAULT
1255 def_bool y
1256 depends on X86_64
1258 config ARCH_SELECT_MEMORY_MODEL
1259 def_bool y
1260 depends on ARCH_SPARSEMEM_ENABLE
1262 config ARCH_MEMORY_PROBE
1263 def_bool X86_64
1264 depends on MEMORY_HOTPLUG
1266 config ARCH_PROC_KCORE_TEXT
1267 def_bool y
1268 depends on X86_64 && PROC_KCORE
1270 config ILLEGAL_POINTER_VALUE
1271 hex
1272 default 0 if X86_32
1273 default 0xdead000000000000 if X86_64
1275 source "mm/Kconfig"
1277 config HIGHPTE
1278 bool "Allocate 3rd-level pagetables from highmem"
1279 depends on HIGHMEM
1280 ---help---
1281 The VM uses one page table entry for each page of physical memory.
1282 For systems with a lot of RAM, this can be wasteful of precious
1283 low memory. Setting this option will put user-space page table
1284 entries in high memory.
1286 config X86_CHECK_BIOS_CORRUPTION
1287 bool "Check for low memory corruption"
1288 ---help---
1289 Periodically check for memory corruption in low memory, which
1290 is suspected to be caused by BIOS. Even when enabled in the
1291 configuration, it is disabled at runtime. Enable it by
1292 setting "memory_corruption_check=1" on the kernel command
1293 line. By default it scans the low 64k of memory every 60
1294 seconds; see the memory_corruption_check_size and
1295 memory_corruption_check_period parameters in
1296 Documentation/kernel-parameters.txt to adjust this.
1298 When enabled with the default parameters, this option has
1299 almost no overhead, as it reserves a relatively small amount
1300 of memory and scans it infrequently. It both detects corruption
1301 and prevents it from affecting the running system.
1303 It is, however, intended as a diagnostic tool; if repeatable
1304 BIOS-originated corruption always affects the same memory,
1305 you can use memmap= to prevent the kernel from using that
1306 memory.
1308 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1309 bool "Set the default setting of memory_corruption_check"
1310 depends on X86_CHECK_BIOS_CORRUPTION
1311 default y
1312 ---help---
1313 Set whether the default state of memory_corruption_check is
1314 on or off.
1316 config X86_RESERVE_LOW
1317 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1318 default 64
1319 range 4 640
1320 ---help---
1321 Specify the amount of low memory to reserve for the BIOS.
1323 The first page contains BIOS data structures that the kernel
1324 must not use, so that page must always be reserved.
1326 By default we reserve the first 64K of physical RAM, as a
1327 number of BIOSes are known to corrupt that memory range
1328 during events such as suspend/resume or monitor cable
1329 insertion, so it must not be used by the kernel.
1331 You can set this to 4 if you are absolutely sure that you
1332 trust the BIOS to get all its memory reservations and usages
1333 right. If you know your BIOS have problems beyond the
1334 default 64K area, you can set this to 640 to avoid using the
1335 entire low memory range.
1337 If you have doubts about the BIOS (e.g. suspend/resume does
1338 not work or there's kernel crashes after certain hardware
1339 hotplug events) then you might want to enable
1340 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1341 typical corruption patterns.
1343 Leave this to the default value of 64 if you are unsure.
1345 config MATH_EMULATION
1346 bool
1347 prompt "Math emulation" if X86_32
1348 ---help---
1349 Linux can emulate a math coprocessor (used for floating point
1350 operations) if you don't have one. 486DX and Pentium processors have
1351 a math coprocessor built in, 486SX and 386 do not, unless you added
1352 a 487DX or 387, respectively. (The messages during boot time can
1353 give you some hints here ["man dmesg"].) Everyone needs either a
1354 coprocessor or this emulation.
1356 If you don't have a math coprocessor, you need to say Y here; if you
1357 say Y here even though you have a coprocessor, the coprocessor will
1358 be used nevertheless. (This behavior can be changed with the kernel
1359 command line option "no387", which comes handy if your coprocessor
1360 is broken. Try "man bootparam" or see the documentation of your boot
1361 loader (lilo or loadlin) about how to pass options to the kernel at
1362 boot time.) This means that it is a good idea to say Y here if you
1363 intend to use this kernel on different machines.
1365 More information about the internals of the Linux math coprocessor
1366 emulation can be found in <file:arch/x86/math-emu/README>.
1368 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1369 kernel, it won't hurt.
1371 config MTRR
1372 def_bool y
1373 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1374 ---help---
1375 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1376 the Memory Type Range Registers (MTRRs) may be used to control
1377 processor access to memory ranges. This is most useful if you have
1378 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1379 allows bus write transfers to be combined into a larger transfer
1380 before bursting over the PCI/AGP bus. This can increase performance
1381 of image write operations 2.5 times or more. Saying Y here creates a
1382 /proc/mtrr file which may be used to manipulate your processor's
1383 MTRRs. Typically the X server should use this.
1385 This code has a reasonably generic interface so that similar
1386 control registers on other processors can be easily supported
1387 as well:
1389 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1390 Registers (ARRs) which provide a similar functionality to MTRRs. For
1391 these, the ARRs are used to emulate the MTRRs.
1392 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1393 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1394 write-combining. All of these processors are supported by this code
1395 and it makes sense to say Y here if you have one of them.
1397 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1398 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1399 can lead to all sorts of problems, so it's good to say Y here.
1401 You can safely say Y even if your machine doesn't have MTRRs, you'll
1402 just add about 9 KB to your kernel.
1404 See <file:Documentation/x86/mtrr.txt> for more information.
1406 config MTRR_SANITIZER
1407 def_bool y
1408 prompt "MTRR cleanup support"
1409 depends on MTRR
1410 ---help---
1411 Convert MTRR layout from continuous to discrete, so X drivers can
1412 add writeback entries.
1414 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1415 The largest mtrr entry size for a continuous block can be set with
1416 mtrr_chunk_size.
1418 If unsure, say Y.
1420 config MTRR_SANITIZER_ENABLE_DEFAULT
1421 int "MTRR cleanup enable value (0-1)"
1422 range 0 1
1423 default "0"
1424 depends on MTRR_SANITIZER
1425 ---help---
1426 Enable mtrr cleanup default value
1428 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1429 int "MTRR cleanup spare reg num (0-7)"
1430 range 0 7
1431 default "1"
1432 depends on MTRR_SANITIZER
1433 ---help---
1434 mtrr cleanup spare entries default, it can be changed via
1435 mtrr_spare_reg_nr=N on the kernel command line.
1437 config X86_PAT
1438 def_bool y
1439 prompt "x86 PAT support" if EXPERT
1440 depends on MTRR
1441 ---help---
1442 Use PAT attributes to setup page level cache control.
1444 PATs are the modern equivalents of MTRRs and are much more
1445 flexible than MTRRs.
1447 Say N here if you see bootup problems (boot crash, boot hang,
1448 spontaneous reboots) or a non-working video driver.
1450 If unsure, say Y.
1452 config ARCH_USES_PG_UNCACHED
1453 def_bool y
1454 depends on X86_PAT
1456 config ARCH_RANDOM
1457 def_bool y
1458 prompt "x86 architectural random number generator" if EXPERT
1459 ---help---
1460 Enable the x86 architectural RDRAND instruction
1461 (Intel Bull Mountain technology) to generate random numbers.
1462 If supported, this is a high bandwidth, cryptographically
1463 secure hardware random number generator.
1465 config EFI
1466 bool "EFI runtime service support"
1467 depends on ACPI
1468 ---help---
1469 This enables the kernel to use EFI runtime services that are
1470 available (such as the EFI variable services).
1472 This option is only useful on systems that have EFI firmware.
1473 In addition, you should use the latest ELILO loader available
1474 at <http://elilo.sourceforge.net> in order to take advantage
1475 of EFI runtime services. However, even with this option, the
1476 resultant kernel should continue to boot on existing non-EFI
1477 platforms.
1479 config SECCOMP
1480 def_bool y
1481 prompt "Enable seccomp to safely compute untrusted bytecode"
1482 ---help---
1483 This kernel feature is useful for number crunching applications
1484 that may need to compute untrusted bytecode during their
1485 execution. By using pipes or other transports made available to
1486 the process as file descriptors supporting the read/write
1487 syscalls, it's possible to isolate those applications in
1488 their own address space using seccomp. Once seccomp is
1489 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1490 and the task is only allowed to execute a few safe syscalls
1491 defined by each seccomp mode.
1493 If unsure, say Y. Only embedded should say N here.
1495 config CC_STACKPROTECTOR
1496 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1497 ---help---
1498 This option turns on the -fstack-protector GCC feature. This
1499 feature puts, at the beginning of functions, a canary value on
1500 the stack just before the return address, and validates
1501 the value just before actually returning. Stack based buffer
1502 overflows (that need to overwrite this return address) now also
1503 overwrite the canary, which gets detected and the attack is then
1504 neutralized via a kernel panic.
1506 This feature requires gcc version 4.2 or above, or a distribution
1507 gcc with the feature backported. Older versions are automatically
1508 detected and for those versions, this configuration option is
1509 ignored. (and a warning is printed during bootup)
1511 source kernel/Kconfig.hz
1513 config KEXEC
1514 bool "kexec system call"
1515 ---help---
1516 kexec is a system call that implements the ability to shutdown your
1517 current kernel, and to start another kernel. It is like a reboot
1518 but it is independent of the system firmware. And like a reboot
1519 you can start any kernel with it, not just Linux.
1521 The name comes from the similarity to the exec system call.
1523 It is an ongoing process to be certain the hardware in a machine
1524 is properly shutdown, so do not be surprised if this code does not
1525 initially work for you. It may help to enable device hotplugging
1526 support. As of this writing the exact hardware interface is
1527 strongly in flux, so no good recommendation can be made.
1529 config CRASH_DUMP
1530 bool "kernel crash dumps"
1531 depends on X86_64 || (X86_32 && HIGHMEM)
1532 ---help---
1533 Generate crash dump after being started by kexec.
1534 This should be normally only set in special crash dump kernels
1535 which are loaded in the main kernel with kexec-tools into
1536 a specially reserved region and then later executed after
1537 a crash by kdump/kexec. The crash dump kernel must be compiled
1538 to a memory address not used by the main kernel or BIOS using
1539 PHYSICAL_START, or it must be built as a relocatable image
1540 (CONFIG_RELOCATABLE=y).
1541 For more details see Documentation/kdump/kdump.txt
1543 config KEXEC_JUMP
1544 bool "kexec jump (EXPERIMENTAL)"
1545 depends on EXPERIMENTAL
1546 depends on KEXEC && HIBERNATION
1547 ---help---
1548 Jump between original kernel and kexeced kernel and invoke
1549 code in physical address mode via KEXEC
1551 config PHYSICAL_START
1552 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1553 default "0x1000000"
1554 ---help---
1555 This gives the physical address where the kernel is loaded.
1557 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1558 bzImage will decompress itself to above physical address and
1559 run from there. Otherwise, bzImage will run from the address where
1560 it has been loaded by the boot loader and will ignore above physical
1561 address.
1563 In normal kdump cases one does not have to set/change this option
1564 as now bzImage can be compiled as a completely relocatable image
1565 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1566 address. This option is mainly useful for the folks who don't want
1567 to use a bzImage for capturing the crash dump and want to use a
1568 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1569 to be specifically compiled to run from a specific memory area
1570 (normally a reserved region) and this option comes handy.
1572 So if you are using bzImage for capturing the crash dump,
1573 leave the value here unchanged to 0x1000000 and set
1574 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1575 for capturing the crash dump change this value to start of
1576 the reserved region. In other words, it can be set based on
1577 the "X" value as specified in the "crashkernel=YM@XM"
1578 command line boot parameter passed to the panic-ed
1579 kernel. Please take a look at Documentation/kdump/kdump.txt
1580 for more details about crash dumps.
1582 Usage of bzImage for capturing the crash dump is recommended as
1583 one does not have to build two kernels. Same kernel can be used
1584 as production kernel and capture kernel. Above option should have
1585 gone away after relocatable bzImage support is introduced. But it
1586 is present because there are users out there who continue to use
1587 vmlinux for dump capture. This option should go away down the
1588 line.
1590 Don't change this unless you know what you are doing.
1592 config RELOCATABLE
1593 bool "Build a relocatable kernel"
1594 default y
1595 ---help---
1596 This builds a kernel image that retains relocation information
1597 so it can be loaded someplace besides the default 1MB.
1598 The relocations tend to make the kernel binary about 10% larger,
1599 but are discarded at runtime.
1601 One use is for the kexec on panic case where the recovery kernel
1602 must live at a different physical address than the primary
1603 kernel.
1605 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1606 it has been loaded at and the compile time physical address
1607 (CONFIG_PHYSICAL_START) is ignored.
1609 # Relocation on x86-32 needs some additional build support
1610 config X86_NEED_RELOCS
1611 def_bool y
1612 depends on X86_32 && RELOCATABLE
1614 config PHYSICAL_ALIGN
1615 hex "Alignment value to which kernel should be aligned" if X86_32
1616 default "0x1000000"
1617 range 0x2000 0x1000000
1618 ---help---
1619 This value puts the alignment restrictions on physical address
1620 where kernel is loaded and run from. Kernel is compiled for an
1621 address which meets above alignment restriction.
1623 If bootloader loads the kernel at a non-aligned address and
1624 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1625 address aligned to above value and run from there.
1627 If bootloader loads the kernel at a non-aligned address and
1628 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1629 load address and decompress itself to the address it has been
1630 compiled for and run from there. The address for which kernel is
1631 compiled already meets above alignment restrictions. Hence the
1632 end result is that kernel runs from a physical address meeting
1633 above alignment restrictions.
1635 Don't change this unless you know what you are doing.
1637 config HOTPLUG_CPU
1638 bool "Support for hot-pluggable CPUs"
1639 depends on SMP && HOTPLUG
1640 ---help---
1641 Say Y here to allow turning CPUs off and on. CPUs can be
1642 controlled through /sys/devices/system/cpu.
1643 ( Note: power management support will enable this option
1644 automatically on SMP systems. )
1645 Say N if you want to disable CPU hotplug.
1647 config COMPAT_VDSO
1648 def_bool y
1649 prompt "Compat VDSO support"
1650 depends on X86_32 || IA32_EMULATION
1651 ---help---
1652 Map the 32-bit VDSO to the predictable old-style address too.
1654 Say N here if you are running a sufficiently recent glibc
1655 version (2.3.3 or later), to remove the high-mapped
1656 VDSO mapping and to exclusively use the randomized VDSO.
1658 If unsure, say Y.
1660 config CMDLINE_BOOL
1661 bool "Built-in kernel command line"
1662 ---help---
1663 Allow for specifying boot arguments to the kernel at
1664 build time. On some systems (e.g. embedded ones), it is
1665 necessary or convenient to provide some or all of the
1666 kernel boot arguments with the kernel itself (that is,
1667 to not rely on the boot loader to provide them.)
1669 To compile command line arguments into the kernel,
1670 set this option to 'Y', then fill in the
1671 the boot arguments in CONFIG_CMDLINE.
1673 Systems with fully functional boot loaders (i.e. non-embedded)
1674 should leave this option set to 'N'.
1676 config CMDLINE
1677 string "Built-in kernel command string"
1678 depends on CMDLINE_BOOL
1679 default ""
1680 ---help---
1681 Enter arguments here that should be compiled into the kernel
1682 image and used at boot time. If the boot loader provides a
1683 command line at boot time, it is appended to this string to
1684 form the full kernel command line, when the system boots.
1686 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1687 change this behavior.
1689 In most cases, the command line (whether built-in or provided
1690 by the boot loader) should specify the device for the root
1691 file system.
1693 config CMDLINE_OVERRIDE
1694 bool "Built-in command line overrides boot loader arguments"
1695 depends on CMDLINE_BOOL
1696 ---help---
1697 Set this option to 'Y' to have the kernel ignore the boot loader
1698 command line, and use ONLY the built-in command line.
1700 This is used to work around broken boot loaders. This should
1701 be set to 'N' under normal conditions.
1703 endmenu
1705 config ARCH_ENABLE_MEMORY_HOTPLUG
1706 def_bool y
1707 depends on X86_64 || (X86_32 && HIGHMEM)
1709 config ARCH_ENABLE_MEMORY_HOTREMOVE
1710 def_bool y
1711 depends on MEMORY_HOTPLUG
1713 config USE_PERCPU_NUMA_NODE_ID
1714 def_bool y
1715 depends on NUMA
1717 menu "Power management and ACPI options"
1719 config ARCH_HIBERNATION_HEADER
1720 def_bool y
1721 depends on X86_64 && HIBERNATION
1723 source "kernel/power/Kconfig"
1725 source "drivers/acpi/Kconfig"
1727 source "drivers/sfi/Kconfig"
1729 config X86_APM_BOOT
1730 def_bool y
1731 depends on APM || APM_MODULE
1733 menuconfig APM
1734 tristate "APM (Advanced Power Management) BIOS support"
1735 depends on X86_32 && PM_SLEEP
1736 ---help---
1737 APM is a BIOS specification for saving power using several different
1738 techniques. This is mostly useful for battery powered laptops with
1739 APM compliant BIOSes. If you say Y here, the system time will be
1740 reset after a RESUME operation, the /proc/apm device will provide
1741 battery status information, and user-space programs will receive
1742 notification of APM "events" (e.g. battery status change).
1744 If you select "Y" here, you can disable actual use of the APM
1745 BIOS by passing the "apm=off" option to the kernel at boot time.
1747 Note that the APM support is almost completely disabled for
1748 machines with more than one CPU.
1750 In order to use APM, you will need supporting software. For location
1751 and more information, read <file:Documentation/power/apm-acpi.txt>
1752 and the Battery Powered Linux mini-HOWTO, available from
1753 <http://www.tldp.org/docs.html#howto>.
1755 This driver does not spin down disk drives (see the hdparm(8)
1756 manpage ("man 8 hdparm") for that), and it doesn't turn off
1757 VESA-compliant "green" monitors.
1759 This driver does not support the TI 4000M TravelMate and the ACER
1760 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1761 desktop machines also don't have compliant BIOSes, and this driver
1762 may cause those machines to panic during the boot phase.
1764 Generally, if you don't have a battery in your machine, there isn't
1765 much point in using this driver and you should say N. If you get
1766 random kernel OOPSes or reboots that don't seem to be related to
1767 anything, try disabling/enabling this option (or disabling/enabling
1768 APM in your BIOS).
1770 Some other things you should try when experiencing seemingly random,
1771 "weird" problems:
1773 1) make sure that you have enough swap space and that it is
1774 enabled.
1775 2) pass the "no-hlt" option to the kernel
1776 3) switch on floating point emulation in the kernel and pass
1777 the "no387" option to the kernel
1778 4) pass the "floppy=nodma" option to the kernel
1779 5) pass the "mem=4M" option to the kernel (thereby disabling
1780 all but the first 4 MB of RAM)
1781 6) make sure that the CPU is not over clocked.
1782 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1783 8) disable the cache from your BIOS settings
1784 9) install a fan for the video card or exchange video RAM
1785 10) install a better fan for the CPU
1786 11) exchange RAM chips
1787 12) exchange the motherboard.
1789 To compile this driver as a module, choose M here: the
1790 module will be called apm.
1792 if APM
1794 config APM_IGNORE_USER_SUSPEND
1795 bool "Ignore USER SUSPEND"
1796 ---help---
1797 This option will ignore USER SUSPEND requests. On machines with a
1798 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1799 series notebooks, it is necessary to say Y because of a BIOS bug.
1801 config APM_DO_ENABLE
1802 bool "Enable PM at boot time"
1803 ---help---
1804 Enable APM features at boot time. From page 36 of the APM BIOS
1805 specification: "When disabled, the APM BIOS does not automatically
1806 power manage devices, enter the Standby State, enter the Suspend
1807 State, or take power saving steps in response to CPU Idle calls."
1808 This driver will make CPU Idle calls when Linux is idle (unless this
1809 feature is turned off -- see "Do CPU IDLE calls", below). This
1810 should always save battery power, but more complicated APM features
1811 will be dependent on your BIOS implementation. You may need to turn
1812 this option off if your computer hangs at boot time when using APM
1813 support, or if it beeps continuously instead of suspending. Turn
1814 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1815 T400CDT. This is off by default since most machines do fine without
1816 this feature.
1818 config APM_CPU_IDLE
1819 bool "Make CPU Idle calls when idle"
1820 ---help---
1821 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1822 On some machines, this can activate improved power savings, such as
1823 a slowed CPU clock rate, when the machine is idle. These idle calls
1824 are made after the idle loop has run for some length of time (e.g.,
1825 333 mS). On some machines, this will cause a hang at boot time or
1826 whenever the CPU becomes idle. (On machines with more than one CPU,
1827 this option does nothing.)
1829 config APM_DISPLAY_BLANK
1830 bool "Enable console blanking using APM"
1831 ---help---
1832 Enable console blanking using the APM. Some laptops can use this to
1833 turn off the LCD backlight when the screen blanker of the Linux
1834 virtual console blanks the screen. Note that this is only used by
1835 the virtual console screen blanker, and won't turn off the backlight
1836 when using the X Window system. This also doesn't have anything to
1837 do with your VESA-compliant power-saving monitor. Further, this
1838 option doesn't work for all laptops -- it might not turn off your
1839 backlight at all, or it might print a lot of errors to the console,
1840 especially if you are using gpm.
1842 config APM_ALLOW_INTS
1843 bool "Allow interrupts during APM BIOS calls"
1844 ---help---
1845 Normally we disable external interrupts while we are making calls to
1846 the APM BIOS as a measure to lessen the effects of a badly behaving
1847 BIOS implementation. The BIOS should reenable interrupts if it
1848 needs to. Unfortunately, some BIOSes do not -- especially those in
1849 many of the newer IBM Thinkpads. If you experience hangs when you
1850 suspend, try setting this to Y. Otherwise, say N.
1852 endif # APM
1854 source "drivers/cpufreq/Kconfig"
1856 source "drivers/cpuidle/Kconfig"
1858 source "drivers/idle/Kconfig"
1860 endmenu
1863 menu "Bus options (PCI etc.)"
1865 config PCI
1866 bool "PCI support"
1867 default y
1868 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1869 ---help---
1870 Find out whether you have a PCI motherboard. PCI is the name of a
1871 bus system, i.e. the way the CPU talks to the other stuff inside
1872 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1873 VESA. If you have PCI, say Y, otherwise N.
1875 choice
1876 prompt "PCI access mode"
1877 depends on X86_32 && PCI
1878 default PCI_GOANY
1879 ---help---
1880 On PCI systems, the BIOS can be used to detect the PCI devices and
1881 determine their configuration. However, some old PCI motherboards
1882 have BIOS bugs and may crash if this is done. Also, some embedded
1883 PCI-based systems don't have any BIOS at all. Linux can also try to
1884 detect the PCI hardware directly without using the BIOS.
1886 With this option, you can specify how Linux should detect the
1887 PCI devices. If you choose "BIOS", the BIOS will be used,
1888 if you choose "Direct", the BIOS won't be used, and if you
1889 choose "MMConfig", then PCI Express MMCONFIG will be used.
1890 If you choose "Any", the kernel will try MMCONFIG, then the
1891 direct access method and falls back to the BIOS if that doesn't
1892 work. If unsure, go with the default, which is "Any".
1894 config PCI_GOBIOS
1895 bool "BIOS"
1897 config PCI_GOMMCONFIG
1898 bool "MMConfig"
1900 config PCI_GODIRECT
1901 bool "Direct"
1903 config PCI_GOOLPC
1904 bool "OLPC XO-1"
1905 depends on OLPC
1907 config PCI_GOANY
1908 bool "Any"
1910 endchoice
1912 config PCI_BIOS
1913 def_bool y
1914 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1916 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1917 config PCI_DIRECT
1918 def_bool y
1919 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
1921 config PCI_MMCONFIG
1922 def_bool y
1923 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
1925 config PCI_OLPC
1926 def_bool y
1927 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1929 config PCI_XEN
1930 def_bool y
1931 depends on PCI && XEN
1932 select SWIOTLB_XEN
1934 config PCI_DOMAINS
1935 def_bool y
1936 depends on PCI
1938 config PCI_MMCONFIG
1939 bool "Support mmconfig PCI config space access"
1940 depends on X86_64 && PCI && ACPI
1942 config PCI_CNB20LE_QUIRK
1943 bool "Read CNB20LE Host Bridge Windows" if EXPERT
1944 default n
1945 depends on PCI && EXPERIMENTAL
1946 help
1947 Read the PCI windows out of the CNB20LE host bridge. This allows
1948 PCI hotplug to work on systems with the CNB20LE chipset which do
1949 not have ACPI.
1951 There's no public spec for this chipset, and this functionality
1952 is known to be incomplete.
1954 You should say N unless you know you need this.
1956 source "drivers/pci/pcie/Kconfig"
1958 source "drivers/pci/Kconfig"
1960 # x86_64 have no ISA slots, but can have ISA-style DMA.
1961 config ISA_DMA_API
1962 bool "ISA-style DMA support" if (X86_64 && EXPERT)
1963 default y
1964 help
1965 Enables ISA-style DMA support for devices requiring such controllers.
1966 If unsure, say Y.
1968 if X86_32
1970 config ISA
1971 bool "ISA support"
1972 ---help---
1973 Find out whether you have ISA slots on your motherboard. ISA is the
1974 name of a bus system, i.e. the way the CPU talks to the other stuff
1975 inside your box. Other bus systems are PCI, EISA, MicroChannel
1976 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1977 newer boards don't support it. If you have ISA, say Y, otherwise N.
1979 config EISA
1980 bool "EISA support"
1981 depends on ISA
1982 ---help---
1983 The Extended Industry Standard Architecture (EISA) bus was
1984 developed as an open alternative to the IBM MicroChannel bus.
1986 The EISA bus provided some of the features of the IBM MicroChannel
1987 bus while maintaining backward compatibility with cards made for
1988 the older ISA bus. The EISA bus saw limited use between 1988 and
1989 1995 when it was made obsolete by the PCI bus.
1991 Say Y here if you are building a kernel for an EISA-based machine.
1993 Otherwise, say N.
1995 source "drivers/eisa/Kconfig"
1997 config MCA
1998 bool "MCA support"
1999 ---help---
2000 MicroChannel Architecture is found in some IBM PS/2 machines and
2001 laptops. It is a bus system similar to PCI or ISA. See
2002 <file:Documentation/mca.txt> (and especially the web page given
2003 there) before attempting to build an MCA bus kernel.
2005 source "drivers/mca/Kconfig"
2007 config SCx200
2008 tristate "NatSemi SCx200 support"
2009 ---help---
2010 This provides basic support for National Semiconductor's
2011 (now AMD's) Geode processors. The driver probes for the
2012 PCI-IDs of several on-chip devices, so its a good dependency
2013 for other scx200_* drivers.
2015 If compiled as a module, the driver is named scx200.
2017 config SCx200HR_TIMER
2018 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2019 depends on SCx200
2020 default y
2021 ---help---
2022 This driver provides a clocksource built upon the on-chip
2023 27MHz high-resolution timer. Its also a workaround for
2024 NSC Geode SC-1100's buggy TSC, which loses time when the
2025 processor goes idle (as is done by the scheduler). The
2026 other workaround is idle=poll boot option.
2028 config OLPC
2029 bool "One Laptop Per Child support"
2030 depends on !X86_PAE
2031 select GPIOLIB
2032 select OF
2033 select OF_PROMTREE
2034 ---help---
2035 Add support for detecting the unique features of the OLPC
2036 XO hardware.
2038 config OLPC_XO1_PM
2039 bool "OLPC XO-1 Power Management"
2040 depends on OLPC && MFD_CS5535 && PM_SLEEP
2041 select MFD_CORE
2042 ---help---
2043 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2045 config OLPC_XO1_RTC
2046 bool "OLPC XO-1 Real Time Clock"
2047 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2048 ---help---
2049 Add support for the XO-1 real time clock, which can be used as a
2050 programmable wakeup source.
2052 config OLPC_XO1_SCI
2053 bool "OLPC XO-1 SCI extras"
2054 depends on OLPC && OLPC_XO1_PM
2055 select POWER_SUPPLY
2056 select GPIO_CS5535
2057 select MFD_CORE
2058 ---help---
2059 Add support for SCI-based features of the OLPC XO-1 laptop:
2060 - EC-driven system wakeups
2061 - Power button
2062 - Ebook switch
2063 - Lid switch
2064 - AC adapter status updates
2065 - Battery status updates
2067 config OLPC_XO15_SCI
2068 bool "OLPC XO-1.5 SCI extras"
2069 depends on OLPC && ACPI
2070 select POWER_SUPPLY
2071 ---help---
2072 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2073 - EC-driven system wakeups
2074 - AC adapter status updates
2075 - Battery status updates
2077 config ALIX
2078 bool "PCEngines ALIX System Support (LED setup)"
2079 select GPIOLIB
2080 ---help---
2081 This option enables system support for the PCEngines ALIX.
2082 At present this just sets up LEDs for GPIO control on
2083 ALIX2/3/6 boards. However, other system specific setup should
2084 get added here.
2086 Note: You must still enable the drivers for GPIO and LED support
2087 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2089 Note: You have to set alix.force=1 for boards with Award BIOS.
2091 endif # X86_32
2093 config AMD_NB
2094 def_bool y
2095 depends on CPU_SUP_AMD && PCI
2097 source "drivers/pcmcia/Kconfig"
2099 source "drivers/pci/hotplug/Kconfig"
2101 config RAPIDIO
2102 bool "RapidIO support"
2103 depends on PCI
2104 default n
2105 help
2106 If you say Y here, the kernel will include drivers and
2107 infrastructure code to support RapidIO interconnect devices.
2109 source "drivers/rapidio/Kconfig"
2111 endmenu
2114 menu "Executable file formats / Emulations"
2116 source "fs/Kconfig.binfmt"
2118 config IA32_EMULATION
2119 bool "IA32 Emulation"
2120 depends on X86_64
2121 select COMPAT_BINFMT_ELF
2122 ---help---
2123 Include code to run 32-bit programs under a 64-bit kernel. You should
2124 likely turn this on, unless you're 100% sure that you don't have any
2125 32-bit programs left.
2127 config IA32_AOUT
2128 tristate "IA32 a.out support"
2129 depends on IA32_EMULATION
2130 ---help---
2131 Support old a.out binaries in the 32bit emulation.
2133 config COMPAT
2134 def_bool y
2135 depends on IA32_EMULATION
2137 config COMPAT_FOR_U64_ALIGNMENT
2138 def_bool COMPAT
2139 depends on X86_64
2141 config SYSVIPC_COMPAT
2142 def_bool y
2143 depends on COMPAT && SYSVIPC
2145 config KEYS_COMPAT
2146 bool
2147 depends on COMPAT && KEYS
2148 default y
2150 endmenu
2153 config HAVE_ATOMIC_IOMAP
2154 def_bool y
2155 depends on X86_32
2157 config HAVE_TEXT_POKE_SMP
2158 bool
2159 select STOP_MACHINE if SMP
2161 source "net/Kconfig"
2163 source "drivers/Kconfig"
2165 source "drivers/firmware/Kconfig"
2167 source "fs/Kconfig"
2169 source "arch/x86/Kconfig.debug"
2171 source "security/Kconfig"
2173 source "crypto/Kconfig"
2175 source "arch/x86/kvm/Kconfig"
2177 source "lib/Kconfig"