xref: /linux/arch/x86/Kconfig (revision aa07a99412f56ad56faecbaa683f3bc0ae99abc2)
1# x86 configuration
2mainmenu "Linux Kernel Configuration for x86"
3
4# Select 32 or 64 bit
5config 64BIT
6	bool "64-bit kernel" if ARCH = "x86"
7	default ARCH = "x86_64"
8	---help---
9	  Say yes to build a 64-bit kernel - formerly known as x86_64
10	  Say no to build a 32-bit kernel - formerly known as i386
11
12config X86_32
13	def_bool !64BIT
14
15config X86_64
16	def_bool 64BIT
17
18### Arch settings
19config X86
20	def_bool y
21	select HAVE_AOUT if X86_32
22	select HAVE_READQ
23	select HAVE_WRITEQ
24	select HAVE_UNSTABLE_SCHED_CLOCK
25	select HAVE_IDE
26	select HAVE_OPROFILE
27	select HAVE_PERF_EVENTS if (!M386 && !M486)
28	select HAVE_IOREMAP_PROT
29	select HAVE_KPROBES
30	select ARCH_WANT_OPTIONAL_GPIOLIB
31	select ARCH_WANT_FRAME_POINTERS
32	select HAVE_DMA_ATTRS
33	select HAVE_KRETPROBES
34	select HAVE_FTRACE_MCOUNT_RECORD
35	select HAVE_DYNAMIC_FTRACE
36	select HAVE_FUNCTION_TRACER
37	select HAVE_FUNCTION_GRAPH_TRACER
38	select HAVE_FUNCTION_GRAPH_FP_TEST
39	select HAVE_FUNCTION_TRACE_MCOUNT_TEST
40	select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
41	select HAVE_SYSCALL_TRACEPOINTS
42	select HAVE_KVM
43	select HAVE_ARCH_KGDB
44	select HAVE_ARCH_TRACEHOOK
45	select HAVE_GENERIC_DMA_COHERENT if X86_32
46	select HAVE_EFFICIENT_UNALIGNED_ACCESS
47	select USER_STACKTRACE_SUPPORT
48	select HAVE_DMA_API_DEBUG
49	select HAVE_KERNEL_GZIP
50	select HAVE_KERNEL_BZIP2
51	select HAVE_KERNEL_LZMA
52	select HAVE_ARCH_KMEMCHECK
53
54config OUTPUT_FORMAT
55	string
56	default "elf32-i386" if X86_32
57	default "elf64-x86-64" if X86_64
58
59config ARCH_DEFCONFIG
60	string
61	default "arch/x86/configs/i386_defconfig" if X86_32
62	default "arch/x86/configs/x86_64_defconfig" if X86_64
63
64config GENERIC_TIME
65	def_bool y
66
67config GENERIC_CMOS_UPDATE
68	def_bool y
69
70config CLOCKSOURCE_WATCHDOG
71	def_bool y
72
73config GENERIC_CLOCKEVENTS
74	def_bool y
75
76config GENERIC_CLOCKEVENTS_BROADCAST
77	def_bool y
78	depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
79
80config LOCKDEP_SUPPORT
81	def_bool y
82
83config STACKTRACE_SUPPORT
84	def_bool y
85
86config HAVE_LATENCYTOP_SUPPORT
87	def_bool y
88
89config MMU
90	def_bool y
91
92config ZONE_DMA
93	def_bool y
94
95config SBUS
96	bool
97
98config GENERIC_ISA_DMA
99	def_bool y
100
101config GENERIC_IOMAP
102	def_bool y
103
104config GENERIC_BUG
105	def_bool y
106	depends on BUG
107	select GENERIC_BUG_RELATIVE_POINTERS if X86_64
108
109config GENERIC_BUG_RELATIVE_POINTERS
110	bool
111
112config GENERIC_HWEIGHT
113	def_bool y
114
115config GENERIC_GPIO
116	bool
117
118config ARCH_MAY_HAVE_PC_FDC
119	def_bool y
120
121config RWSEM_GENERIC_SPINLOCK
122	def_bool !X86_XADD
123
124config RWSEM_XCHGADD_ALGORITHM
125	def_bool X86_XADD
126
127config ARCH_HAS_CPU_IDLE_WAIT
128	def_bool y
129
130config GENERIC_CALIBRATE_DELAY
131	def_bool y
132
133config GENERIC_TIME_VSYSCALL
134	bool
135	default X86_64
136
137config ARCH_HAS_CPU_RELAX
138	def_bool y
139
140config ARCH_HAS_DEFAULT_IDLE
141	def_bool y
142
143config ARCH_HAS_CACHE_LINE_SIZE
144	def_bool y
145
146config HAVE_SETUP_PER_CPU_AREA
147	def_bool y
148
149config NEED_PER_CPU_EMBED_FIRST_CHUNK
150	def_bool y
151
152config NEED_PER_CPU_PAGE_FIRST_CHUNK
153	def_bool y
154
155config HAVE_CPUMASK_OF_CPU_MAP
156	def_bool X86_64_SMP
157
158config ARCH_HIBERNATION_POSSIBLE
159	def_bool y
160
161config ARCH_SUSPEND_POSSIBLE
162	def_bool y
163
164config ZONE_DMA32
165	bool
166	default X86_64
167
168config ARCH_POPULATES_NODE_MAP
169	def_bool y
170
171config AUDIT_ARCH
172	bool
173	default X86_64
174
175config ARCH_SUPPORTS_OPTIMIZED_INLINING
176	def_bool y
177
178config ARCH_SUPPORTS_DEBUG_PAGEALLOC
179	def_bool y
180
181config HAVE_INTEL_TXT
182	def_bool y
183	depends on EXPERIMENTAL && DMAR && ACPI
184
185# Use the generic interrupt handling code in kernel/irq/:
186config GENERIC_HARDIRQS
187	bool
188	default y
189
190config GENERIC_HARDIRQS_NO__DO_IRQ
191       def_bool y
192
193config GENERIC_IRQ_PROBE
194	bool
195	default y
196
197config GENERIC_PENDING_IRQ
198	bool
199	depends on GENERIC_HARDIRQS && SMP
200	default y
201
202config USE_GENERIC_SMP_HELPERS
203	def_bool y
204	depends on SMP
205
206config X86_32_SMP
207	def_bool y
208	depends on X86_32 && SMP
209
210config X86_64_SMP
211	def_bool y
212	depends on X86_64 && SMP
213
214config X86_HT
215	bool
216	depends on SMP
217	default y
218
219config X86_TRAMPOLINE
220	bool
221	depends on SMP || (64BIT && ACPI_SLEEP)
222	default y
223
224config X86_32_LAZY_GS
225	def_bool y
226	depends on X86_32 && !CC_STACKPROTECTOR
227
228config KTIME_SCALAR
229	def_bool X86_32
230source "init/Kconfig"
231source "kernel/Kconfig.freezer"
232
233menu "Processor type and features"
234
235source "kernel/time/Kconfig"
236
237config SMP
238	bool "Symmetric multi-processing support"
239	---help---
240	  This enables support for systems with more than one CPU. If you have
241	  a system with only one CPU, like most personal computers, say N. If
242	  you have a system with more than one CPU, say Y.
243
244	  If you say N here, the kernel will run on single and multiprocessor
245	  machines, but will use only one CPU of a multiprocessor machine. If
246	  you say Y here, the kernel will run on many, but not all,
247	  singleprocessor machines. On a singleprocessor machine, the kernel
248	  will run faster if you say N here.
249
250	  Note that if you say Y here and choose architecture "586" or
251	  "Pentium" under "Processor family", the kernel will not work on 486
252	  architectures. Similarly, multiprocessor kernels for the "PPro"
253	  architecture may not work on all Pentium based boards.
254
255	  People using multiprocessor machines who say Y here should also say
256	  Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
257	  Management" code will be disabled if you say Y here.
258
259	  See also <file:Documentation/i386/IO-APIC.txt>,
260	  <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
261	  <http://www.tldp.org/docs.html#howto>.
262
263	  If you don't know what to do here, say N.
264
265config X86_X2APIC
266	bool "Support x2apic"
267	depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
268	---help---
269	  This enables x2apic support on CPUs that have this feature.
270
271	  This allows 32-bit apic IDs (so it can support very large systems),
272	  and accesses the local apic via MSRs not via mmio.
273
274	  If you don't know what to do here, say N.
275
276config SPARSE_IRQ
277	bool "Support sparse irq numbering"
278	depends on PCI_MSI || HT_IRQ
279	---help---
280	  This enables support for sparse irqs. This is useful for distro
281	  kernels that want to define a high CONFIG_NR_CPUS value but still
282	  want to have low kernel memory footprint on smaller machines.
283
284	  ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
285	    out the irq_desc[] array in a more NUMA-friendly way. )
286
287	  If you don't know what to do here, say N.
288
289config NUMA_IRQ_DESC
290	def_bool y
291	depends on SPARSE_IRQ && NUMA
292
293config X86_MPPARSE
294	bool "Enable MPS table" if ACPI
295	default y
296	depends on X86_LOCAL_APIC
297	---help---
298	  For old smp systems that do not have proper acpi support. Newer systems
299	  (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
300
301config X86_BIGSMP
302	bool "Support for big SMP systems with more than 8 CPUs"
303	depends on X86_32 && SMP
304	---help---
305	  This option is needed for the systems that have more than 8 CPUs
306
307if X86_32
308config X86_EXTENDED_PLATFORM
309	bool "Support for extended (non-PC) x86 platforms"
310	default y
311	---help---
312	  If you disable this option then the kernel will only support
313	  standard PC platforms. (which covers the vast majority of
314	  systems out there.)
315
316	  If you enable this option then you'll be able to select support
317	  for the following (non-PC) 32 bit x86 platforms:
318		AMD Elan
319		NUMAQ (IBM/Sequent)
320		RDC R-321x SoC
321		SGI 320/540 (Visual Workstation)
322		Summit/EXA (IBM x440)
323		Unisys ES7000 IA32 series
324		Moorestown MID devices
325
326	  If you have one of these systems, or if you want to build a
327	  generic distribution kernel, say Y here - otherwise say N.
328endif
329
330if X86_64
331config X86_EXTENDED_PLATFORM
332	bool "Support for extended (non-PC) x86 platforms"
333	default y
334	---help---
335	  If you disable this option then the kernel will only support
336	  standard PC platforms. (which covers the vast majority of
337	  systems out there.)
338
339	  If you enable this option then you'll be able to select support
340	  for the following (non-PC) 64 bit x86 platforms:
341		ScaleMP vSMP
342		SGI Ultraviolet
343
344	  If you have one of these systems, or if you want to build a
345	  generic distribution kernel, say Y here - otherwise say N.
346endif
347# This is an alphabetically sorted list of 64 bit extended platforms
348# Please maintain the alphabetic order if and when there are additions
349
350config X86_VSMP
351	bool "ScaleMP vSMP"
352	select PARAVIRT
353	depends on X86_64 && PCI
354	depends on X86_EXTENDED_PLATFORM
355	---help---
356	  Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
357	  supposed to run on these EM64T-based machines.  Only choose this option
358	  if you have one of these machines.
359
360config X86_UV
361	bool "SGI Ultraviolet"
362	depends on X86_64
363	depends on X86_EXTENDED_PLATFORM
364	depends on NUMA
365	depends on X86_X2APIC
366	---help---
367	  This option is needed in order to support SGI Ultraviolet systems.
368	  If you don't have one of these, you should say N here.
369
370# Following is an alphabetically sorted list of 32 bit extended platforms
371# Please maintain the alphabetic order if and when there are additions
372
373config X86_ELAN
374	bool "AMD Elan"
375	depends on X86_32
376	depends on X86_EXTENDED_PLATFORM
377	---help---
378	  Select this for an AMD Elan processor.
379
380	  Do not use this option for K6/Athlon/Opteron processors!
381
382	  If unsure, choose "PC-compatible" instead.
383
384config X86_MRST
385       bool "Moorestown MID platform"
386	depends on X86_32
387	depends on X86_EXTENDED_PLATFORM
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.
395
396config 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.
406
407config 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.
416
417# Alphabetically sorted list of Non standard 32 bit platforms
418
419config X86_NUMAQ
420	bool "NUMAQ (IBM/Sequent)"
421	depends on X86_32_NON_STANDARD
422	select NUMA
423	select X86_MPPARSE
424	---help---
425	  This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
426	  NUMA multiquad box. This changes the way that processors are
427	  bootstrapped, and uses Clustered Logical APIC addressing mode instead
428	  of Flat Logical.  You will need a new lynxer.elf file to flash your
429	  firmware with - send email to <Martin.Bligh@us.ibm.com>.
430
431config X86_SUPPORTS_MEMORY_FAILURE
432	bool
433	# MCE code calls memory_failure():
434	depends on X86_MCE
435	# On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
436	depends on !X86_NUMAQ
437	# On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
438	depends on X86_64 || !SPARSEMEM
439	select ARCH_SUPPORTS_MEMORY_FAILURE
440	default y
441
442config 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.
449
450	  Say Y here to create a kernel to run on the SGI 320 or 540.
451
452	  A kernel compiled for the Visual Workstation will run on general
453	  PCs as well. See <file:Documentation/sgi-visws.txt> for details.
454
455config 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.
461
462config 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.
468
469config 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.
478
479	  If in doubt, say "Y".
480
481menuconfig 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.
486
487	  If you say N, all options in this submenu will be skipped and disabled.
488
489if PARAVIRT_GUEST
490
491source "arch/x86/xen/Kconfig"
492
493config VMI
494	bool "VMI Guest support"
495	select PARAVIRT
496	depends on X86_32
497	---help---
498	  VMI provides a paravirtualized interface to the VMware ESX server
499	  (it could be used by other hypervisors in theory too, but is not
500	  at the moment), by linking the kernel to a GPL-ed ROM module
501	  provided by the hypervisor.
502
503config KVM_CLOCK
504	bool "KVM paravirtualized clock"
505	select PARAVIRT
506	select PARAVIRT_CLOCK
507	---help---
508	  Turning on this option will allow you to run a paravirtualized clock
509	  when running over the KVM hypervisor. Instead of relying on a PIT
510	  (or probably other) emulation by the underlying device model, the host
511	  provides the guest with timing infrastructure such as time of day, and
512	  system time
513
514config KVM_GUEST
515	bool "KVM Guest support"
516	select PARAVIRT
517	---help---
518	  This option enables various optimizations for running under the KVM
519	  hypervisor.
520
521source "arch/x86/lguest/Kconfig"
522
523config PARAVIRT
524	bool "Enable paravirtualization code"
525	---help---
526	  This changes the kernel so it can modify itself when it is run
527	  under a hypervisor, potentially improving performance significantly
528	  over full virtualization.  However, when run without a hypervisor
529	  the kernel is theoretically slower and slightly larger.
530
531config PARAVIRT_SPINLOCKS
532	bool "Paravirtualization layer for spinlocks"
533	depends on PARAVIRT && SMP && EXPERIMENTAL
534	---help---
535	  Paravirtualized spinlocks allow a pvops backend to replace the
536	  spinlock implementation with something virtualization-friendly
537	  (for example, block the virtual CPU rather than spinning).
538
539	  Unfortunately the downside is an up to 5% performance hit on
540	  native kernels, with various workloads.
541
542	  If you are unsure how to answer this question, answer N.
543
544config PARAVIRT_CLOCK
545	bool
546	default n
547
548endif
549
550config PARAVIRT_DEBUG
551	bool "paravirt-ops debugging"
552	depends on PARAVIRT && DEBUG_KERNEL
553	---help---
554	  Enable to debug paravirt_ops internals.  Specifically, BUG if
555	  a paravirt_op is missing when it is called.
556
557config MEMTEST
558	bool "Memtest"
559	---help---
560	  This option adds a kernel parameter 'memtest', which allows memtest
561	  to be set.
562	        memtest=0, mean disabled; -- default
563	        memtest=1, mean do 1 test pattern;
564	        ...
565	        memtest=4, mean do 4 test patterns.
566	  If you are unsure how to answer this question, answer N.
567
568config X86_SUMMIT_NUMA
569	def_bool y
570	depends on X86_32 && NUMA && X86_32_NON_STANDARD
571
572config X86_CYCLONE_TIMER
573	def_bool y
574	depends on X86_32_NON_STANDARD
575
576source "arch/x86/Kconfig.cpu"
577
578config HPET_TIMER
579	def_bool X86_64
580	prompt "HPET Timer Support" if X86_32
581	---help---
582	  Use the IA-PC HPET (High Precision Event Timer) to manage
583	  time in preference to the PIT and RTC, if a HPET is
584	  present.
585	  HPET is the next generation timer replacing legacy 8254s.
586	  The HPET provides a stable time base on SMP
587	  systems, unlike the TSC, but it is more expensive to access,
588	  as it is off-chip.  You can find the HPET spec at
589	  <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
590
591	  You can safely choose Y here.  However, HPET will only be
592	  activated if the platform and the BIOS support this feature.
593	  Otherwise the 8254 will be used for timing services.
594
595	  Choose N to continue using the legacy 8254 timer.
596
597config HPET_EMULATE_RTC
598	def_bool y
599	depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
600
601# Mark as embedded because too many people got it wrong.
602# The code disables itself when not needed.
603config DMI
604	default y
605	bool "Enable DMI scanning" if EMBEDDED
606	---help---
607	  Enabled scanning of DMI to identify machine quirks. Say Y
608	  here unless you have verified that your setup is not
609	  affected by entries in the DMI blacklist. Required by PNP
610	  BIOS code.
611
612config GART_IOMMU
613	bool "GART IOMMU support" if EMBEDDED
614	default y
615	select SWIOTLB
616	depends on X86_64 && PCI
617	---help---
618	  Support for full DMA access of devices with 32bit memory access only
619	  on systems with more than 3GB. This is usually needed for USB,
620	  sound, many IDE/SATA chipsets and some other devices.
621	  Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
622	  based hardware IOMMU and a software bounce buffer based IOMMU used
623	  on Intel systems and as fallback.
624	  The code is only active when needed (enough memory and limited
625	  device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
626	  too.
627
628config CALGARY_IOMMU
629	bool "IBM Calgary IOMMU support"
630	select SWIOTLB
631	depends on X86_64 && PCI && EXPERIMENTAL
632	---help---
633	  Support for hardware IOMMUs in IBM's xSeries x366 and x460
634	  systems. Needed to run systems with more than 3GB of memory
635	  properly with 32-bit PCI devices that do not support DAC
636	  (Double Address Cycle). Calgary also supports bus level
637	  isolation, where all DMAs pass through the IOMMU.  This
638	  prevents them from going anywhere except their intended
639	  destination. This catches hard-to-find kernel bugs and
640	  mis-behaving drivers and devices that do not use the DMA-API
641	  properly to set up their DMA buffers.  The IOMMU can be
642	  turned off at boot time with the iommu=off parameter.
643	  Normally the kernel will make the right choice by itself.
644	  If unsure, say Y.
645
646config CALGARY_IOMMU_ENABLED_BY_DEFAULT
647	def_bool y
648	prompt "Should Calgary be enabled by default?"
649	depends on CALGARY_IOMMU
650	---help---
651	  Should Calgary be enabled by default? if you choose 'y', Calgary
652	  will be used (if it exists). If you choose 'n', Calgary will not be
653	  used even if it exists. If you choose 'n' and would like to use
654	  Calgary anyway, pass 'iommu=calgary' on the kernel command line.
655	  If unsure, say Y.
656
657config AMD_IOMMU
658	bool "AMD IOMMU support"
659	select SWIOTLB
660	select PCI_MSI
661	depends on X86_64 && PCI && ACPI
662	---help---
663	  With this option you can enable support for AMD IOMMU hardware in
664	  your system. An IOMMU is a hardware component which provides
665	  remapping of DMA memory accesses from devices. With an AMD IOMMU you
666	  can isolate the the DMA memory of different devices and protect the
667	  system from misbehaving device drivers or hardware.
668
669	  You can find out if your system has an AMD IOMMU if you look into
670	  your BIOS for an option to enable it or if you have an IVRS ACPI
671	  table.
672
673config AMD_IOMMU_STATS
674	bool "Export AMD IOMMU statistics to debugfs"
675	depends on AMD_IOMMU
676	select DEBUG_FS
677	---help---
678	  This option enables code in the AMD IOMMU driver to collect various
679	  statistics about whats happening in the driver and exports that
680	  information to userspace via debugfs.
681	  If unsure, say N.
682
683# need this always selected by IOMMU for the VIA workaround
684config SWIOTLB
685	def_bool y if X86_64
686	---help---
687	  Support for software bounce buffers used on x86-64 systems
688	  which don't have a hardware IOMMU (e.g. the current generation
689	  of Intel's x86-64 CPUs). Using this PCI devices which can only
690	  access 32-bits of memory can be used on systems with more than
691	  3 GB of memory. If unsure, say Y.
692
693config IOMMU_HELPER
694	def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
695
696config IOMMU_API
697	def_bool (AMD_IOMMU || DMAR)
698
699config MAXSMP
700	bool "Configure Maximum number of SMP Processors and NUMA Nodes"
701	depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
702	select CPUMASK_OFFSTACK
703	default n
704	---help---
705	  Configure maximum number of CPUS and NUMA Nodes for this architecture.
706	  If unsure, say N.
707
708config NR_CPUS
709	int "Maximum number of CPUs" if SMP && !MAXSMP
710	range 2 8 if SMP && X86_32 && !X86_BIGSMP
711	range 2 512 if SMP && !MAXSMP
712	default "1" if !SMP
713	default "4096" if MAXSMP
714	default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
715	default "8" if SMP
716	---help---
717	  This allows you to specify the maximum number of CPUs which this
718	  kernel will support.  The maximum supported value is 512 and the
719	  minimum value which makes sense is 2.
720
721	  This is purely to save memory - each supported CPU adds
722	  approximately eight kilobytes to the kernel image.
723
724config SCHED_SMT
725	bool "SMT (Hyperthreading) scheduler support"
726	depends on X86_HT
727	---help---
728	  SMT scheduler support improves the CPU scheduler's decision making
729	  when dealing with Intel Pentium 4 chips with HyperThreading at a
730	  cost of slightly increased overhead in some places. If unsure say
731	  N here.
732
733config SCHED_MC
734	def_bool y
735	prompt "Multi-core scheduler support"
736	depends on X86_HT
737	---help---
738	  Multi-core scheduler support improves the CPU scheduler's decision
739	  making when dealing with multi-core CPU chips at a cost of slightly
740	  increased overhead in some places. If unsure say N here.
741
742source "kernel/Kconfig.preempt"
743
744config X86_UP_APIC
745	bool "Local APIC support on uniprocessors"
746	depends on X86_32 && !SMP && !X86_32_NON_STANDARD
747	---help---
748	  A local APIC (Advanced Programmable Interrupt Controller) is an
749	  integrated interrupt controller in the CPU. If you have a single-CPU
750	  system which has a processor with a local APIC, you can say Y here to
751	  enable and use it. If you say Y here even though your machine doesn't
752	  have a local APIC, then the kernel will still run with no slowdown at
753	  all. The local APIC supports CPU-generated self-interrupts (timer,
754	  performance counters), and the NMI watchdog which detects hard
755	  lockups.
756
757config X86_UP_IOAPIC
758	bool "IO-APIC support on uniprocessors"
759	depends on X86_UP_APIC
760	---help---
761	  An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
762	  SMP-capable replacement for PC-style interrupt controllers. Most
763	  SMP systems and many recent uniprocessor systems have one.
764
765	  If you have a single-CPU system with an IO-APIC, you can say Y here
766	  to use it. If you say Y here even though your machine doesn't have
767	  an IO-APIC, then the kernel will still run with no slowdown at all.
768
769config X86_LOCAL_APIC
770	def_bool y
771	depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
772
773config X86_IO_APIC
774	def_bool y
775	depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
776
777config X86_VISWS_APIC
778	def_bool y
779	depends on X86_32 && X86_VISWS
780
781config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
782	bool "Reroute for broken boot IRQs"
783	default n
784	depends on X86_IO_APIC
785	---help---
786	  This option enables a workaround that fixes a source of
787	  spurious interrupts. This is recommended when threaded
788	  interrupt handling is used on systems where the generation of
789	  superfluous "boot interrupts" cannot be disabled.
790
791	  Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
792	  entry in the chipset's IO-APIC is masked (as, e.g. the RT
793	  kernel does during interrupt handling). On chipsets where this
794	  boot IRQ generation cannot be disabled, this workaround keeps
795	  the original IRQ line masked so that only the equivalent "boot
796	  IRQ" is delivered to the CPUs. The workaround also tells the
797	  kernel to set up the IRQ handler on the boot IRQ line. In this
798	  way only one interrupt is delivered to the kernel. Otherwise
799	  the spurious second interrupt may cause the kernel to bring
800	  down (vital) interrupt lines.
801
802	  Only affects "broken" chipsets. Interrupt sharing may be
803	  increased on these systems.
804
805config X86_MCE
806	bool "Machine Check / overheating reporting"
807	---help---
808	  Machine Check support allows the processor to notify the
809	  kernel if it detects a problem (e.g. overheating, data corruption).
810	  The action the kernel takes depends on the severity of the problem,
811	  ranging from warning messages to halting the machine.
812
813config X86_MCE_INTEL
814	def_bool y
815	prompt "Intel MCE features"
816	depends on X86_MCE && X86_LOCAL_APIC
817	---help---
818	   Additional support for intel specific MCE features such as
819	   the thermal monitor.
820
821config X86_MCE_AMD
822	def_bool y
823	prompt "AMD MCE features"
824	depends on X86_MCE && X86_LOCAL_APIC
825	---help---
826	   Additional support for AMD specific MCE features such as
827	   the DRAM Error Threshold.
828
829config X86_ANCIENT_MCE
830	def_bool n
831	depends on X86_32 && X86_MCE
832	prompt "Support for old Pentium 5 / WinChip machine checks"
833	---help---
834	  Include support for machine check handling on old Pentium 5 or WinChip
835	  systems. These typically need to be enabled explicitely on the command
836	  line.
837
838config X86_MCE_THRESHOLD
839	depends on X86_MCE_AMD || X86_MCE_INTEL
840	bool
841	default y
842
843config X86_MCE_INJECT
844	depends on X86_MCE
845	tristate "Machine check injector support"
846	---help---
847	  Provide support for injecting machine checks for testing purposes.
848	  If you don't know what a machine check is and you don't do kernel
849	  QA it is safe to say n.
850
851config X86_THERMAL_VECTOR
852	def_bool y
853	depends on X86_MCE_INTEL
854
855config VM86
856	bool "Enable VM86 support" if EMBEDDED
857	default y
858	depends on X86_32
859	---help---
860	  This option is required by programs like DOSEMU to run 16-bit legacy
861	  code on X86 processors. It also may be needed by software like
862	  XFree86 to initialize some video cards via BIOS. Disabling this
863	  option saves about 6k.
864
865config TOSHIBA
866	tristate "Toshiba Laptop support"
867	depends on X86_32
868	---help---
869	  This adds a driver to safely access the System Management Mode of
870	  the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
871	  not work on models with a Phoenix BIOS. The System Management Mode
872	  is used to set the BIOS and power saving options on Toshiba portables.
873
874	  For information on utilities to make use of this driver see the
875	  Toshiba Linux utilities web site at:
876	  <http://www.buzzard.org.uk/toshiba/>.
877
878	  Say Y if you intend to run this kernel on a Toshiba portable.
879	  Say N otherwise.
880
881config I8K
882	tristate "Dell laptop support"
883	---help---
884	  This adds a driver to safely access the System Management Mode
885	  of the CPU on the Dell Inspiron 8000. The System Management Mode
886	  is used to read cpu temperature and cooling fan status and to
887	  control the fans on the I8K portables.
888
889	  This driver has been tested only on the Inspiron 8000 but it may
890	  also work with other Dell laptops. You can force loading on other
891	  models by passing the parameter `force=1' to the module. Use at
892	  your own risk.
893
894	  For information on utilities to make use of this driver see the
895	  I8K Linux utilities web site at:
896	  <http://people.debian.org/~dz/i8k/>
897
898	  Say Y if you intend to run this kernel on a Dell Inspiron 8000.
899	  Say N otherwise.
900
901config X86_REBOOTFIXUPS
902	bool "Enable X86 board specific fixups for reboot"
903	depends on X86_32
904	---help---
905	  This enables chipset and/or board specific fixups to be done
906	  in order to get reboot to work correctly. This is only needed on
907	  some combinations of hardware and BIOS. The symptom, for which
908	  this config is intended, is when reboot ends with a stalled/hung
909	  system.
910
911	  Currently, the only fixup is for the Geode machines using
912	  CS5530A and CS5536 chipsets and the RDC R-321x SoC.
913
914	  Say Y if you want to enable the fixup. Currently, it's safe to
915	  enable this option even if you don't need it.
916	  Say N otherwise.
917
918config MICROCODE
919	tristate "/dev/cpu/microcode - microcode support"
920	select FW_LOADER
921	---help---
922	  If you say Y here, you will be able to update the microcode on
923	  certain Intel and AMD processors. The Intel support is for the
924	  IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
925	  Pentium 4, Xeon etc. The AMD support is for family 0x10 and
926	  0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
927	  You will obviously need the actual microcode binary data itself
928	  which is not shipped with the Linux kernel.
929
930	  This option selects the general module only, you need to select
931	  at least one vendor specific module as well.
932
933	  To compile this driver as a module, choose M here: the
934	  module will be called microcode.
935
936config MICROCODE_INTEL
937	bool "Intel microcode patch loading support"
938	depends on MICROCODE
939	default MICROCODE
940	select FW_LOADER
941	---help---
942	  This options enables microcode patch loading support for Intel
943	  processors.
944
945	  For latest news and information on obtaining all the required
946	  Intel ingredients for this driver, check:
947	  <http://www.urbanmyth.org/microcode/>.
948
949config MICROCODE_AMD
950	bool "AMD microcode patch loading support"
951	depends on MICROCODE
952	select FW_LOADER
953	---help---
954	  If you select this option, microcode patch loading support for AMD
955	  processors will be enabled.
956
957config MICROCODE_OLD_INTERFACE
958	def_bool y
959	depends on MICROCODE
960
961config X86_MSR
962	tristate "/dev/cpu/*/msr - Model-specific register support"
963	---help---
964	  This device gives privileged processes access to the x86
965	  Model-Specific Registers (MSRs).  It is a character device with
966	  major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
967	  MSR accesses are directed to a specific CPU on multi-processor
968	  systems.
969
970config X86_CPUID
971	tristate "/dev/cpu/*/cpuid - CPU information support"
972	---help---
973	  This device gives processes access to the x86 CPUID instruction to
974	  be executed on a specific processor.  It is a character device
975	  with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
976	  /dev/cpu/31/cpuid.
977
978config X86_CPU_DEBUG
979	tristate "/sys/kernel/debug/x86/cpu/* - CPU Debug support"
980	---help---
981	  If you select this option, this will provide various x86 CPUs
982	  information through debugfs.
983
984choice
985	prompt "High Memory Support"
986	default HIGHMEM4G if !X86_NUMAQ
987	default HIGHMEM64G if X86_NUMAQ
988	depends on X86_32
989
990config NOHIGHMEM
991	bool "off"
992	depends on !X86_NUMAQ
993	---help---
994	  Linux can use up to 64 Gigabytes of physical memory on x86 systems.
995	  However, the address space of 32-bit x86 processors is only 4
996	  Gigabytes large. That means that, if you have a large amount of
997	  physical memory, not all of it can be "permanently mapped" by the
998	  kernel. The physical memory that's not permanently mapped is called
999	  "high memory".
1000
1001	  If you are compiling a kernel which will never run on a machine with
1002	  more than 1 Gigabyte total physical RAM, answer "off" here (default
1003	  choice and suitable for most users). This will result in a "3GB/1GB"
1004	  split: 3GB are mapped so that each process sees a 3GB virtual memory
1005	  space and the remaining part of the 4GB virtual memory space is used
1006	  by the kernel to permanently map as much physical memory as
1007	  possible.
1008
1009	  If the machine has between 1 and 4 Gigabytes physical RAM, then
1010	  answer "4GB" here.
1011
1012	  If more than 4 Gigabytes is used then answer "64GB" here. This
1013	  selection turns Intel PAE (Physical Address Extension) mode on.
1014	  PAE implements 3-level paging on IA32 processors. PAE is fully
1015	  supported by Linux, PAE mode is implemented on all recent Intel
1016	  processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1017	  then the kernel will not boot on CPUs that don't support PAE!
1018
1019	  The actual amount of total physical memory will either be
1020	  auto detected or can be forced by using a kernel command line option
1021	  such as "mem=256M". (Try "man bootparam" or see the documentation of
1022	  your boot loader (lilo or loadlin) about how to pass options to the
1023	  kernel at boot time.)
1024
1025	  If unsure, say "off".
1026
1027config HIGHMEM4G
1028	bool "4GB"
1029	depends on !X86_NUMAQ
1030	---help---
1031	  Select this if you have a 32-bit processor and between 1 and 4
1032	  gigabytes of physical RAM.
1033
1034config HIGHMEM64G
1035	bool "64GB"
1036	depends on !M386 && !M486
1037	select X86_PAE
1038	---help---
1039	  Select this if you have a 32-bit processor and more than 4
1040	  gigabytes of physical RAM.
1041
1042endchoice
1043
1044choice
1045	depends on EXPERIMENTAL
1046	prompt "Memory split" if EMBEDDED
1047	default VMSPLIT_3G
1048	depends on X86_32
1049	---help---
1050	  Select the desired split between kernel and user memory.
1051
1052	  If the address range available to the kernel is less than the
1053	  physical memory installed, the remaining memory will be available
1054	  as "high memory". Accessing high memory is a little more costly
1055	  than low memory, as it needs to be mapped into the kernel first.
1056	  Note that increasing the kernel address space limits the range
1057	  available to user programs, making the address space there
1058	  tighter.  Selecting anything other than the default 3G/1G split
1059	  will also likely make your kernel incompatible with binary-only
1060	  kernel modules.
1061
1062	  If you are not absolutely sure what you are doing, leave this
1063	  option alone!
1064
1065	config VMSPLIT_3G
1066		bool "3G/1G user/kernel split"
1067	config VMSPLIT_3G_OPT
1068		depends on !X86_PAE
1069		bool "3G/1G user/kernel split (for full 1G low memory)"
1070	config VMSPLIT_2G
1071		bool "2G/2G user/kernel split"
1072	config VMSPLIT_2G_OPT
1073		depends on !X86_PAE
1074		bool "2G/2G user/kernel split (for full 2G low memory)"
1075	config VMSPLIT_1G
1076		bool "1G/3G user/kernel split"
1077endchoice
1078
1079config PAGE_OFFSET
1080	hex
1081	default 0xB0000000 if VMSPLIT_3G_OPT
1082	default 0x80000000 if VMSPLIT_2G
1083	default 0x78000000 if VMSPLIT_2G_OPT
1084	default 0x40000000 if VMSPLIT_1G
1085	default 0xC0000000
1086	depends on X86_32
1087
1088config HIGHMEM
1089	def_bool y
1090	depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1091
1092config X86_PAE
1093	bool "PAE (Physical Address Extension) Support"
1094	depends on X86_32 && !HIGHMEM4G
1095	---help---
1096	  PAE is required for NX support, and furthermore enables
1097	  larger swapspace support for non-overcommit purposes. It
1098	  has the cost of more pagetable lookup overhead, and also
1099	  consumes more pagetable space per process.
1100
1101config ARCH_PHYS_ADDR_T_64BIT
1102	def_bool X86_64 || X86_PAE
1103
1104config DIRECT_GBPAGES
1105	bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
1106	default y
1107	depends on X86_64
1108	---help---
1109	  Allow the kernel linear mapping to use 1GB pages on CPUs that
1110	  support it. This can improve the kernel's performance a tiny bit by
1111	  reducing TLB pressure. If in doubt, say "Y".
1112
1113# Common NUMA Features
1114config NUMA
1115	bool "Numa Memory Allocation and Scheduler Support"
1116	depends on SMP
1117	depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1118	default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1119	---help---
1120	  Enable NUMA (Non Uniform Memory Access) support.
1121
1122	  The kernel will try to allocate memory used by a CPU on the
1123	  local memory controller of the CPU and add some more
1124	  NUMA awareness to the kernel.
1125
1126	  For 64-bit this is recommended if the system is Intel Core i7
1127	  (or later), AMD Opteron, or EM64T NUMA.
1128
1129	  For 32-bit this is only needed on (rare) 32-bit-only platforms
1130	  that support NUMA topologies, such as NUMAQ / Summit, or if you
1131	  boot a 32-bit kernel on a 64-bit NUMA platform.
1132
1133	  Otherwise, you should say N.
1134
1135comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1136	depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1137
1138config K8_NUMA
1139	def_bool y
1140	prompt "Old style AMD Opteron NUMA detection"
1141	depends on X86_64 && NUMA && PCI
1142	---help---
1143	  Enable K8 NUMA node topology detection.  You should say Y here if
1144	  you have a multi processor AMD K8 system. This uses an old
1145	  method to read the NUMA configuration directly from the builtin
1146	  Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
1147	  instead, which also takes priority if both are compiled in.
1148
1149config X86_64_ACPI_NUMA
1150	def_bool y
1151	prompt "ACPI NUMA detection"
1152	depends on X86_64 && NUMA && ACPI && PCI
1153	select ACPI_NUMA
1154	---help---
1155	  Enable ACPI SRAT based node topology detection.
1156
1157# Some NUMA nodes have memory ranges that span
1158# other nodes.  Even though a pfn is valid and
1159# between a node's start and end pfns, it may not
1160# reside on that node.  See memmap_init_zone()
1161# for details.
1162config NODES_SPAN_OTHER_NODES
1163	def_bool y
1164	depends on X86_64_ACPI_NUMA
1165
1166config NUMA_EMU
1167	bool "NUMA emulation"
1168	depends on X86_64 && NUMA
1169	---help---
1170	  Enable NUMA emulation. A flat machine will be split
1171	  into virtual nodes when booted with "numa=fake=N", where N is the
1172	  number of nodes. This is only useful for debugging.
1173
1174config NODES_SHIFT
1175	int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1176	range 1 9
1177	default "9" if MAXSMP
1178	default "6" if X86_64
1179	default "4" if X86_NUMAQ
1180	default "3"
1181	depends on NEED_MULTIPLE_NODES
1182	---help---
1183	  Specify the maximum number of NUMA Nodes available on the target
1184	  system.  Increases memory reserved to accommodate various tables.
1185
1186config HAVE_ARCH_BOOTMEM
1187	def_bool y
1188	depends on X86_32 && NUMA
1189
1190config ARCH_HAVE_MEMORY_PRESENT
1191	def_bool y
1192	depends on X86_32 && DISCONTIGMEM
1193
1194config NEED_NODE_MEMMAP_SIZE
1195	def_bool y
1196	depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1197
1198config HAVE_ARCH_ALLOC_REMAP
1199	def_bool y
1200	depends on X86_32 && NUMA
1201
1202config ARCH_FLATMEM_ENABLE
1203	def_bool y
1204	depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
1205
1206config ARCH_DISCONTIGMEM_ENABLE
1207	def_bool y
1208	depends on NUMA && X86_32
1209
1210config ARCH_DISCONTIGMEM_DEFAULT
1211	def_bool y
1212	depends on NUMA && X86_32
1213
1214config ARCH_PROC_KCORE_TEXT
1215	def_bool y
1216	depends on X86_64 && PROC_KCORE
1217
1218config ARCH_SPARSEMEM_DEFAULT
1219	def_bool y
1220	depends on X86_64
1221
1222config ARCH_SPARSEMEM_ENABLE
1223	def_bool y
1224	depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1225	select SPARSEMEM_STATIC if X86_32
1226	select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1227
1228config ARCH_SELECT_MEMORY_MODEL
1229	def_bool y
1230	depends on ARCH_SPARSEMEM_ENABLE
1231
1232config ARCH_MEMORY_PROBE
1233	def_bool X86_64
1234	depends on MEMORY_HOTPLUG
1235
1236source "mm/Kconfig"
1237
1238config HIGHPTE
1239	bool "Allocate 3rd-level pagetables from highmem"
1240	depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1241	---help---
1242	  The VM uses one page table entry for each page of physical memory.
1243	  For systems with a lot of RAM, this can be wasteful of precious
1244	  low memory.  Setting this option will put user-space page table
1245	  entries in high memory.
1246
1247config X86_CHECK_BIOS_CORRUPTION
1248	bool "Check for low memory corruption"
1249	---help---
1250	  Periodically check for memory corruption in low memory, which
1251	  is suspected to be caused by BIOS.  Even when enabled in the
1252	  configuration, it is disabled at runtime.  Enable it by
1253	  setting "memory_corruption_check=1" on the kernel command
1254	  line.  By default it scans the low 64k of memory every 60
1255	  seconds; see the memory_corruption_check_size and
1256	  memory_corruption_check_period parameters in
1257	  Documentation/kernel-parameters.txt to adjust this.
1258
1259	  When enabled with the default parameters, this option has
1260	  almost no overhead, as it reserves a relatively small amount
1261	  of memory and scans it infrequently.  It both detects corruption
1262	  and prevents it from affecting the running system.
1263
1264	  It is, however, intended as a diagnostic tool; if repeatable
1265	  BIOS-originated corruption always affects the same memory,
1266	  you can use memmap= to prevent the kernel from using that
1267	  memory.
1268
1269config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1270	bool "Set the default setting of memory_corruption_check"
1271	depends on X86_CHECK_BIOS_CORRUPTION
1272	default y
1273	---help---
1274	  Set whether the default state of memory_corruption_check is
1275	  on or off.
1276
1277config X86_RESERVE_LOW_64K
1278	bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
1279	default y
1280	---help---
1281	  Reserve the first 64K of physical RAM on BIOSes that are known
1282	  to potentially corrupt that memory range. A numbers of BIOSes are
1283	  known to utilize this area during suspend/resume, so it must not
1284	  be used by the kernel.
1285
1286	  Set this to N if you are absolutely sure that you trust the BIOS
1287	  to get all its memory reservations and usages right.
1288
1289	  If you have doubts about the BIOS (e.g. suspend/resume does not
1290	  work or there's kernel crashes after certain hardware hotplug
1291	  events) and it's not AMI or Phoenix, then you might want to enable
1292	  X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
1293	  corruption patterns.
1294
1295	  Say Y if unsure.
1296
1297config MATH_EMULATION
1298	bool
1299	prompt "Math emulation" if X86_32
1300	---help---
1301	  Linux can emulate a math coprocessor (used for floating point
1302	  operations) if you don't have one. 486DX and Pentium processors have
1303	  a math coprocessor built in, 486SX and 386 do not, unless you added
1304	  a 487DX or 387, respectively. (The messages during boot time can
1305	  give you some hints here ["man dmesg"].) Everyone needs either a
1306	  coprocessor or this emulation.
1307
1308	  If you don't have a math coprocessor, you need to say Y here; if you
1309	  say Y here even though you have a coprocessor, the coprocessor will
1310	  be used nevertheless. (This behavior can be changed with the kernel
1311	  command line option "no387", which comes handy if your coprocessor
1312	  is broken. Try "man bootparam" or see the documentation of your boot
1313	  loader (lilo or loadlin) about how to pass options to the kernel at
1314	  boot time.) This means that it is a good idea to say Y here if you
1315	  intend to use this kernel on different machines.
1316
1317	  More information about the internals of the Linux math coprocessor
1318	  emulation can be found in <file:arch/x86/math-emu/README>.
1319
1320	  If you are not sure, say Y; apart from resulting in a 66 KB bigger
1321	  kernel, it won't hurt.
1322
1323config MTRR
1324	bool "MTRR (Memory Type Range Register) support"
1325	---help---
1326	  On Intel P6 family processors (Pentium Pro, Pentium II and later)
1327	  the Memory Type Range Registers (MTRRs) may be used to control
1328	  processor access to memory ranges. This is most useful if you have
1329	  a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1330	  allows bus write transfers to be combined into a larger transfer
1331	  before bursting over the PCI/AGP bus. This can increase performance
1332	  of image write operations 2.5 times or more. Saying Y here creates a
1333	  /proc/mtrr file which may be used to manipulate your processor's
1334	  MTRRs. Typically the X server should use this.
1335
1336	  This code has a reasonably generic interface so that similar
1337	  control registers on other processors can be easily supported
1338	  as well:
1339
1340	  The Cyrix 6x86, 6x86MX and M II processors have Address Range
1341	  Registers (ARRs) which provide a similar functionality to MTRRs. For
1342	  these, the ARRs are used to emulate the MTRRs.
1343	  The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1344	  MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1345	  write-combining. All of these processors are supported by this code
1346	  and it makes sense to say Y here if you have one of them.
1347
1348	  Saying Y here also fixes a problem with buggy SMP BIOSes which only
1349	  set the MTRRs for the boot CPU and not for the secondary CPUs. This
1350	  can lead to all sorts of problems, so it's good to say Y here.
1351
1352	  You can safely say Y even if your machine doesn't have MTRRs, you'll
1353	  just add about 9 KB to your kernel.
1354
1355	  See <file:Documentation/x86/mtrr.txt> for more information.
1356
1357config MTRR_SANITIZER
1358	def_bool y
1359	prompt "MTRR cleanup support"
1360	depends on MTRR
1361	---help---
1362	  Convert MTRR layout from continuous to discrete, so X drivers can
1363	  add writeback entries.
1364
1365	  Can be disabled with disable_mtrr_cleanup on the kernel command line.
1366	  The largest mtrr entry size for a continuous block can be set with
1367	  mtrr_chunk_size.
1368
1369	  If unsure, say Y.
1370
1371config MTRR_SANITIZER_ENABLE_DEFAULT
1372	int "MTRR cleanup enable value (0-1)"
1373	range 0 1
1374	default "0"
1375	depends on MTRR_SANITIZER
1376	---help---
1377	  Enable mtrr cleanup default value
1378
1379config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1380	int "MTRR cleanup spare reg num (0-7)"
1381	range 0 7
1382	default "1"
1383	depends on MTRR_SANITIZER
1384	---help---
1385	  mtrr cleanup spare entries default, it can be changed via
1386	  mtrr_spare_reg_nr=N on the kernel command line.
1387
1388config X86_PAT
1389	bool
1390	prompt "x86 PAT support"
1391	depends on MTRR
1392	---help---
1393	  Use PAT attributes to setup page level cache control.
1394
1395	  PATs are the modern equivalents of MTRRs and are much more
1396	  flexible than MTRRs.
1397
1398	  Say N here if you see bootup problems (boot crash, boot hang,
1399	  spontaneous reboots) or a non-working video driver.
1400
1401	  If unsure, say Y.
1402
1403config ARCH_USES_PG_UNCACHED
1404	def_bool y
1405	depends on X86_PAT
1406
1407config EFI
1408	bool "EFI runtime service support"
1409	depends on ACPI
1410	---help---
1411	  This enables the kernel to use EFI runtime services that are
1412	  available (such as the EFI variable services).
1413
1414	  This option is only useful on systems that have EFI firmware.
1415	  In addition, you should use the latest ELILO loader available
1416	  at <http://elilo.sourceforge.net> in order to take advantage
1417	  of EFI runtime services. However, even with this option, the
1418	  resultant kernel should continue to boot on existing non-EFI
1419	  platforms.
1420
1421config SECCOMP
1422	def_bool y
1423	prompt "Enable seccomp to safely compute untrusted bytecode"
1424	---help---
1425	  This kernel feature is useful for number crunching applications
1426	  that may need to compute untrusted bytecode during their
1427	  execution. By using pipes or other transports made available to
1428	  the process as file descriptors supporting the read/write
1429	  syscalls, it's possible to isolate those applications in
1430	  their own address space using seccomp. Once seccomp is
1431	  enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1432	  and the task is only allowed to execute a few safe syscalls
1433	  defined by each seccomp mode.
1434
1435	  If unsure, say Y. Only embedded should say N here.
1436
1437config CC_STACKPROTECTOR_ALL
1438	bool
1439
1440config CC_STACKPROTECTOR
1441	bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1442	select CC_STACKPROTECTOR_ALL
1443	---help---
1444	  This option turns on the -fstack-protector GCC feature. This
1445	  feature puts, at the beginning of functions, a canary value on
1446	  the stack just before the return address, and validates
1447	  the value just before actually returning.  Stack based buffer
1448	  overflows (that need to overwrite this return address) now also
1449	  overwrite the canary, which gets detected and the attack is then
1450	  neutralized via a kernel panic.
1451
1452	  This feature requires gcc version 4.2 or above, or a distribution
1453	  gcc with the feature backported. Older versions are automatically
1454	  detected and for those versions, this configuration option is
1455	  ignored. (and a warning is printed during bootup)
1456
1457source kernel/Kconfig.hz
1458
1459config KEXEC
1460	bool "kexec system call"
1461	---help---
1462	  kexec is a system call that implements the ability to shutdown your
1463	  current kernel, and to start another kernel.  It is like a reboot
1464	  but it is independent of the system firmware.   And like a reboot
1465	  you can start any kernel with it, not just Linux.
1466
1467	  The name comes from the similarity to the exec system call.
1468
1469	  It is an ongoing process to be certain the hardware in a machine
1470	  is properly shutdown, so do not be surprised if this code does not
1471	  initially work for you.  It may help to enable device hotplugging
1472	  support.  As of this writing the exact hardware interface is
1473	  strongly in flux, so no good recommendation can be made.
1474
1475config CRASH_DUMP
1476	bool "kernel crash dumps"
1477	depends on X86_64 || (X86_32 && HIGHMEM)
1478	---help---
1479	  Generate crash dump after being started by kexec.
1480	  This should be normally only set in special crash dump kernels
1481	  which are loaded in the main kernel with kexec-tools into
1482	  a specially reserved region and then later executed after
1483	  a crash by kdump/kexec. The crash dump kernel must be compiled
1484	  to a memory address not used by the main kernel or BIOS using
1485	  PHYSICAL_START, or it must be built as a relocatable image
1486	  (CONFIG_RELOCATABLE=y).
1487	  For more details see Documentation/kdump/kdump.txt
1488
1489config KEXEC_JUMP
1490	bool "kexec jump (EXPERIMENTAL)"
1491	depends on EXPERIMENTAL
1492	depends on KEXEC && HIBERNATION
1493	---help---
1494	  Jump between original kernel and kexeced kernel and invoke
1495	  code in physical address mode via KEXEC
1496
1497config PHYSICAL_START
1498	hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1499	default "0x1000000"
1500	---help---
1501	  This gives the physical address where the kernel is loaded.
1502
1503	  If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1504	  bzImage will decompress itself to above physical address and
1505	  run from there. Otherwise, bzImage will run from the address where
1506	  it has been loaded by the boot loader and will ignore above physical
1507	  address.
1508
1509	  In normal kdump cases one does not have to set/change this option
1510	  as now bzImage can be compiled as a completely relocatable image
1511	  (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1512	  address. This option is mainly useful for the folks who don't want
1513	  to use a bzImage for capturing the crash dump and want to use a
1514	  vmlinux instead. vmlinux is not relocatable hence a kernel needs
1515	  to be specifically compiled to run from a specific memory area
1516	  (normally a reserved region) and this option comes handy.
1517
1518	  So if you are using bzImage for capturing the crash dump,
1519	  leave the value here unchanged to 0x1000000 and set
1520	  CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
1521	  for capturing the crash dump change this value to start of
1522	  the reserved region.  In other words, it can be set based on
1523	  the "X" value as specified in the "crashkernel=YM@XM"
1524	  command line boot parameter passed to the panic-ed
1525	  kernel. Please take a look at Documentation/kdump/kdump.txt
1526	  for more details about crash dumps.
1527
1528	  Usage of bzImage for capturing the crash dump is recommended as
1529	  one does not have to build two kernels. Same kernel can be used
1530	  as production kernel and capture kernel. Above option should have
1531	  gone away after relocatable bzImage support is introduced. But it
1532	  is present because there are users out there who continue to use
1533	  vmlinux for dump capture. This option should go away down the
1534	  line.
1535
1536	  Don't change this unless you know what you are doing.
1537
1538config RELOCATABLE
1539	bool "Build a relocatable kernel"
1540	default y
1541	---help---
1542	  This builds a kernel image that retains relocation information
1543	  so it can be loaded someplace besides the default 1MB.
1544	  The relocations tend to make the kernel binary about 10% larger,
1545	  but are discarded at runtime.
1546
1547	  One use is for the kexec on panic case where the recovery kernel
1548	  must live at a different physical address than the primary
1549	  kernel.
1550
1551	  Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1552	  it has been loaded at and the compile time physical address
1553	  (CONFIG_PHYSICAL_START) is ignored.
1554
1555# Relocation on x86-32 needs some additional build support
1556config X86_NEED_RELOCS
1557	def_bool y
1558	depends on X86_32 && RELOCATABLE
1559
1560config PHYSICAL_ALIGN
1561	hex
1562	prompt "Alignment value to which kernel should be aligned" if X86_32
1563	default "0x1000000"
1564	range 0x2000 0x1000000
1565	---help---
1566	  This value puts the alignment restrictions on physical address
1567	  where kernel is loaded and run from. Kernel is compiled for an
1568	  address which meets above alignment restriction.
1569
1570	  If bootloader loads the kernel at a non-aligned address and
1571	  CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1572	  address aligned to above value and run from there.
1573
1574	  If bootloader loads the kernel at a non-aligned address and
1575	  CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1576	  load address and decompress itself to the address it has been
1577	  compiled for and run from there. The address for which kernel is
1578	  compiled already meets above alignment restrictions. Hence the
1579	  end result is that kernel runs from a physical address meeting
1580	  above alignment restrictions.
1581
1582	  Don't change this unless you know what you are doing.
1583
1584config HOTPLUG_CPU
1585	bool "Support for hot-pluggable CPUs"
1586	depends on SMP && HOTPLUG
1587	---help---
1588	  Say Y here to allow turning CPUs off and on. CPUs can be
1589	  controlled through /sys/devices/system/cpu.
1590	  ( Note: power management support will enable this option
1591	    automatically on SMP systems. )
1592	  Say N if you want to disable CPU hotplug.
1593
1594config COMPAT_VDSO
1595	def_bool y
1596	prompt "Compat VDSO support"
1597	depends on X86_32 || IA32_EMULATION
1598	---help---
1599	  Map the 32-bit VDSO to the predictable old-style address too.
1600	---help---
1601	  Say N here if you are running a sufficiently recent glibc
1602	  version (2.3.3 or later), to remove the high-mapped
1603	  VDSO mapping and to exclusively use the randomized VDSO.
1604
1605	  If unsure, say Y.
1606
1607config CMDLINE_BOOL
1608	bool "Built-in kernel command line"
1609	default n
1610	---help---
1611	  Allow for specifying boot arguments to the kernel at
1612	  build time.  On some systems (e.g. embedded ones), it is
1613	  necessary or convenient to provide some or all of the
1614	  kernel boot arguments with the kernel itself (that is,
1615	  to not rely on the boot loader to provide them.)
1616
1617	  To compile command line arguments into the kernel,
1618	  set this option to 'Y', then fill in the
1619	  the boot arguments in CONFIG_CMDLINE.
1620
1621	  Systems with fully functional boot loaders (i.e. non-embedded)
1622	  should leave this option set to 'N'.
1623
1624config CMDLINE
1625	string "Built-in kernel command string"
1626	depends on CMDLINE_BOOL
1627	default ""
1628	---help---
1629	  Enter arguments here that should be compiled into the kernel
1630	  image and used at boot time.  If the boot loader provides a
1631	  command line at boot time, it is appended to this string to
1632	  form the full kernel command line, when the system boots.
1633
1634	  However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1635	  change this behavior.
1636
1637	  In most cases, the command line (whether built-in or provided
1638	  by the boot loader) should specify the device for the root
1639	  file system.
1640
1641config CMDLINE_OVERRIDE
1642	bool "Built-in command line overrides boot loader arguments"
1643	default n
1644	depends on CMDLINE_BOOL
1645	---help---
1646	  Set this option to 'Y' to have the kernel ignore the boot loader
1647	  command line, and use ONLY the built-in command line.
1648
1649	  This is used to work around broken boot loaders.  This should
1650	  be set to 'N' under normal conditions.
1651
1652endmenu
1653
1654config ARCH_ENABLE_MEMORY_HOTPLUG
1655	def_bool y
1656	depends on X86_64 || (X86_32 && HIGHMEM)
1657
1658config ARCH_ENABLE_MEMORY_HOTREMOVE
1659	def_bool y
1660	depends on MEMORY_HOTPLUG
1661
1662config HAVE_ARCH_EARLY_PFN_TO_NID
1663	def_bool X86_64
1664	depends on NUMA
1665
1666menu "Power management and ACPI options"
1667
1668config ARCH_HIBERNATION_HEADER
1669	def_bool y
1670	depends on X86_64 && HIBERNATION
1671
1672source "kernel/power/Kconfig"
1673
1674source "drivers/acpi/Kconfig"
1675
1676source "drivers/sfi/Kconfig"
1677
1678config X86_APM_BOOT
1679	bool
1680	default y
1681	depends on APM || APM_MODULE
1682
1683menuconfig APM
1684	tristate "APM (Advanced Power Management) BIOS support"
1685	depends on X86_32 && PM_SLEEP
1686	---help---
1687	  APM is a BIOS specification for saving power using several different
1688	  techniques. This is mostly useful for battery powered laptops with
1689	  APM compliant BIOSes. If you say Y here, the system time will be
1690	  reset after a RESUME operation, the /proc/apm device will provide
1691	  battery status information, and user-space programs will receive
1692	  notification of APM "events" (e.g. battery status change).
1693
1694	  If you select "Y" here, you can disable actual use of the APM
1695	  BIOS by passing the "apm=off" option to the kernel at boot time.
1696
1697	  Note that the APM support is almost completely disabled for
1698	  machines with more than one CPU.
1699
1700	  In order to use APM, you will need supporting software. For location
1701	  and more information, read <file:Documentation/power/pm.txt> and the
1702	  Battery Powered Linux mini-HOWTO, available from
1703	  <http://www.tldp.org/docs.html#howto>.
1704
1705	  This driver does not spin down disk drives (see the hdparm(8)
1706	  manpage ("man 8 hdparm") for that), and it doesn't turn off
1707	  VESA-compliant "green" monitors.
1708
1709	  This driver does not support the TI 4000M TravelMate and the ACER
1710	  486/DX4/75 because they don't have compliant BIOSes. Many "green"
1711	  desktop machines also don't have compliant BIOSes, and this driver
1712	  may cause those machines to panic during the boot phase.
1713
1714	  Generally, if you don't have a battery in your machine, there isn't
1715	  much point in using this driver and you should say N. If you get
1716	  random kernel OOPSes or reboots that don't seem to be related to
1717	  anything, try disabling/enabling this option (or disabling/enabling
1718	  APM in your BIOS).
1719
1720	  Some other things you should try when experiencing seemingly random,
1721	  "weird" problems:
1722
1723	  1) make sure that you have enough swap space and that it is
1724	  enabled.
1725	  2) pass the "no-hlt" option to the kernel
1726	  3) switch on floating point emulation in the kernel and pass
1727	  the "no387" option to the kernel
1728	  4) pass the "floppy=nodma" option to the kernel
1729	  5) pass the "mem=4M" option to the kernel (thereby disabling
1730	  all but the first 4 MB of RAM)
1731	  6) make sure that the CPU is not over clocked.
1732	  7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1733	  8) disable the cache from your BIOS settings
1734	  9) install a fan for the video card or exchange video RAM
1735	  10) install a better fan for the CPU
1736	  11) exchange RAM chips
1737	  12) exchange the motherboard.
1738
1739	  To compile this driver as a module, choose M here: the
1740	  module will be called apm.
1741
1742if APM
1743
1744config APM_IGNORE_USER_SUSPEND
1745	bool "Ignore USER SUSPEND"
1746	---help---
1747	  This option will ignore USER SUSPEND requests. On machines with a
1748	  compliant APM BIOS, you want to say N. However, on the NEC Versa M
1749	  series notebooks, it is necessary to say Y because of a BIOS bug.
1750
1751config APM_DO_ENABLE
1752	bool "Enable PM at boot time"
1753	---help---
1754	  Enable APM features at boot time. From page 36 of the APM BIOS
1755	  specification: "When disabled, the APM BIOS does not automatically
1756	  power manage devices, enter the Standby State, enter the Suspend
1757	  State, or take power saving steps in response to CPU Idle calls."
1758	  This driver will make CPU Idle calls when Linux is idle (unless this
1759	  feature is turned off -- see "Do CPU IDLE calls", below). This
1760	  should always save battery power, but more complicated APM features
1761	  will be dependent on your BIOS implementation. You may need to turn
1762	  this option off if your computer hangs at boot time when using APM
1763	  support, or if it beeps continuously instead of suspending. Turn
1764	  this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1765	  T400CDT. This is off by default since most machines do fine without
1766	  this feature.
1767
1768config APM_CPU_IDLE
1769	bool "Make CPU Idle calls when idle"
1770	---help---
1771	  Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1772	  On some machines, this can activate improved power savings, such as
1773	  a slowed CPU clock rate, when the machine is idle. These idle calls
1774	  are made after the idle loop has run for some length of time (e.g.,
1775	  333 mS). On some machines, this will cause a hang at boot time or
1776	  whenever the CPU becomes idle. (On machines with more than one CPU,
1777	  this option does nothing.)
1778
1779config APM_DISPLAY_BLANK
1780	bool "Enable console blanking using APM"
1781	---help---
1782	  Enable console blanking using the APM. Some laptops can use this to
1783	  turn off the LCD backlight when the screen blanker of the Linux
1784	  virtual console blanks the screen. Note that this is only used by
1785	  the virtual console screen blanker, and won't turn off the backlight
1786	  when using the X Window system. This also doesn't have anything to
1787	  do with your VESA-compliant power-saving monitor. Further, this
1788	  option doesn't work for all laptops -- it might not turn off your
1789	  backlight at all, or it might print a lot of errors to the console,
1790	  especially if you are using gpm.
1791
1792config APM_ALLOW_INTS
1793	bool "Allow interrupts during APM BIOS calls"
1794	---help---
1795	  Normally we disable external interrupts while we are making calls to
1796	  the APM BIOS as a measure to lessen the effects of a badly behaving
1797	  BIOS implementation.  The BIOS should reenable interrupts if it
1798	  needs to.  Unfortunately, some BIOSes do not -- especially those in
1799	  many of the newer IBM Thinkpads.  If you experience hangs when you
1800	  suspend, try setting this to Y.  Otherwise, say N.
1801
1802endif # APM
1803
1804source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1805
1806source "drivers/cpuidle/Kconfig"
1807
1808source "drivers/idle/Kconfig"
1809
1810endmenu
1811
1812
1813menu "Bus options (PCI etc.)"
1814
1815config PCI
1816	bool "PCI support"
1817	default y
1818	select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1819	---help---
1820	  Find out whether you have a PCI motherboard. PCI is the name of a
1821	  bus system, i.e. the way the CPU talks to the other stuff inside
1822	  your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1823	  VESA. If you have PCI, say Y, otherwise N.
1824
1825choice
1826	prompt "PCI access mode"
1827	depends on X86_32 && PCI
1828	default PCI_GOANY
1829	---help---
1830	  On PCI systems, the BIOS can be used to detect the PCI devices and
1831	  determine their configuration. However, some old PCI motherboards
1832	  have BIOS bugs and may crash if this is done. Also, some embedded
1833	  PCI-based systems don't have any BIOS at all. Linux can also try to
1834	  detect the PCI hardware directly without using the BIOS.
1835
1836	  With this option, you can specify how Linux should detect the
1837	  PCI devices. If you choose "BIOS", the BIOS will be used,
1838	  if you choose "Direct", the BIOS won't be used, and if you
1839	  choose "MMConfig", then PCI Express MMCONFIG will be used.
1840	  If you choose "Any", the kernel will try MMCONFIG, then the
1841	  direct access method and falls back to the BIOS if that doesn't
1842	  work. If unsure, go with the default, which is "Any".
1843
1844config PCI_GOBIOS
1845	bool "BIOS"
1846
1847config PCI_GOMMCONFIG
1848	bool "MMConfig"
1849
1850config PCI_GODIRECT
1851	bool "Direct"
1852
1853config PCI_GOOLPC
1854	bool "OLPC"
1855	depends on OLPC
1856
1857config PCI_GOANY
1858	bool "Any"
1859
1860endchoice
1861
1862config PCI_BIOS
1863	def_bool y
1864	depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1865
1866# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1867config PCI_DIRECT
1868	def_bool y
1869	depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1870
1871config PCI_MMCONFIG
1872	def_bool y
1873	depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
1874
1875config PCI_OLPC
1876	def_bool y
1877	depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1878
1879config PCI_DOMAINS
1880	def_bool y
1881	depends on PCI
1882
1883config PCI_MMCONFIG
1884	bool "Support mmconfig PCI config space access"
1885	depends on X86_64 && PCI && ACPI
1886
1887config DMAR
1888	bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1889	depends on PCI_MSI && ACPI && EXPERIMENTAL
1890	help
1891	  DMA remapping (DMAR) devices support enables independent address
1892	  translations for Direct Memory Access (DMA) from devices.
1893	  These DMA remapping devices are reported via ACPI tables
1894	  and include PCI device scope covered by these DMA
1895	  remapping devices.
1896
1897config DMAR_DEFAULT_ON
1898	def_bool y
1899	prompt "Enable DMA Remapping Devices by default"
1900	depends on DMAR
1901	help
1902	  Selecting this option will enable a DMAR device at boot time if
1903	  one is found. If this option is not selected, DMAR support can
1904	  be enabled by passing intel_iommu=on to the kernel. It is
1905	  recommended you say N here while the DMAR code remains
1906	  experimental.
1907
1908config DMAR_BROKEN_GFX_WA
1909	def_bool n
1910	prompt "Workaround broken graphics drivers (going away soon)"
1911	depends on DMAR && BROKEN
1912	---help---
1913	  Current Graphics drivers tend to use physical address
1914	  for DMA and avoid using DMA APIs. Setting this config
1915	  option permits the IOMMU driver to set a unity map for
1916	  all the OS-visible memory. Hence the driver can continue
1917	  to use physical addresses for DMA, at least until this
1918	  option is removed in the 2.6.32 kernel.
1919
1920config DMAR_FLOPPY_WA
1921	def_bool y
1922	depends on DMAR
1923	---help---
1924	  Floppy disk drivers are known to bypass DMA API calls
1925	  thereby failing to work when IOMMU is enabled. This
1926	  workaround will setup a 1:1 mapping for the first
1927	  16MiB to make floppy (an ISA device) work.
1928
1929config INTR_REMAP
1930	bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1931	depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
1932	---help---
1933	  Supports Interrupt remapping for IO-APIC and MSI devices.
1934	  To use x2apic mode in the CPU's which support x2APIC enhancements or
1935	  to support platforms with CPU's having > 8 bit APIC ID, say Y.
1936
1937source "drivers/pci/pcie/Kconfig"
1938
1939source "drivers/pci/Kconfig"
1940
1941# x86_64 have no ISA slots, but do have ISA-style DMA.
1942config ISA_DMA_API
1943	def_bool y
1944
1945if X86_32
1946
1947config ISA
1948	bool "ISA support"
1949	---help---
1950	  Find out whether you have ISA slots on your motherboard.  ISA is the
1951	  name of a bus system, i.e. the way the CPU talks to the other stuff
1952	  inside your box.  Other bus systems are PCI, EISA, MicroChannel
1953	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
1954	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
1955
1956config EISA
1957	bool "EISA support"
1958	depends on ISA
1959	---help---
1960	  The Extended Industry Standard Architecture (EISA) bus was
1961	  developed as an open alternative to the IBM MicroChannel bus.
1962
1963	  The EISA bus provided some of the features of the IBM MicroChannel
1964	  bus while maintaining backward compatibility with cards made for
1965	  the older ISA bus.  The EISA bus saw limited use between 1988 and
1966	  1995 when it was made obsolete by the PCI bus.
1967
1968	  Say Y here if you are building a kernel for an EISA-based machine.
1969
1970	  Otherwise, say N.
1971
1972source "drivers/eisa/Kconfig"
1973
1974config MCA
1975	bool "MCA support"
1976	---help---
1977	  MicroChannel Architecture is found in some IBM PS/2 machines and
1978	  laptops.  It is a bus system similar to PCI or ISA. See
1979	  <file:Documentation/mca.txt> (and especially the web page given
1980	  there) before attempting to build an MCA bus kernel.
1981
1982source "drivers/mca/Kconfig"
1983
1984config SCx200
1985	tristate "NatSemi SCx200 support"
1986	---help---
1987	  This provides basic support for National Semiconductor's
1988	  (now AMD's) Geode processors.  The driver probes for the
1989	  PCI-IDs of several on-chip devices, so its a good dependency
1990	  for other scx200_* drivers.
1991
1992	  If compiled as a module, the driver is named scx200.
1993
1994config SCx200HR_TIMER
1995	tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1996	depends on SCx200 && GENERIC_TIME
1997	default y
1998	---help---
1999	  This driver provides a clocksource built upon the on-chip
2000	  27MHz high-resolution timer.  Its also a workaround for
2001	  NSC Geode SC-1100's buggy TSC, which loses time when the
2002	  processor goes idle (as is done by the scheduler).  The
2003	  other workaround is idle=poll boot option.
2004
2005config GEODE_MFGPT_TIMER
2006	def_bool y
2007	prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
2008	depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
2009	---help---
2010	  This driver provides a clock event source based on the MFGPT
2011	  timer(s) in the CS5535 and CS5536 companion chip for the geode.
2012	  MFGPTs have a better resolution and max interval than the
2013	  generic PIT, and are suitable for use as high-res timers.
2014
2015config OLPC
2016	bool "One Laptop Per Child support"
2017	default n
2018	---help---
2019	  Add support for detecting the unique features of the OLPC
2020	  XO hardware.
2021
2022endif # X86_32
2023
2024config K8_NB
2025	def_bool y
2026	depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
2027
2028source "drivers/pcmcia/Kconfig"
2029
2030source "drivers/pci/hotplug/Kconfig"
2031
2032endmenu
2033
2034
2035menu "Executable file formats / Emulations"
2036
2037source "fs/Kconfig.binfmt"
2038
2039config IA32_EMULATION
2040	bool "IA32 Emulation"
2041	depends on X86_64
2042	select COMPAT_BINFMT_ELF
2043	---help---
2044	  Include code to run 32-bit programs under a 64-bit kernel. You should
2045	  likely turn this on, unless you're 100% sure that you don't have any
2046	  32-bit programs left.
2047
2048config IA32_AOUT
2049	tristate "IA32 a.out support"
2050	depends on IA32_EMULATION
2051	---help---
2052	  Support old a.out binaries in the 32bit emulation.
2053
2054config COMPAT
2055	def_bool y
2056	depends on IA32_EMULATION
2057
2058config COMPAT_FOR_U64_ALIGNMENT
2059	def_bool COMPAT
2060	depends on X86_64
2061
2062config SYSVIPC_COMPAT
2063	def_bool y
2064	depends on COMPAT && SYSVIPC
2065
2066endmenu
2067
2068
2069config HAVE_ATOMIC_IOMAP
2070	def_bool y
2071	depends on X86_32
2072
2073source "net/Kconfig"
2074
2075source "drivers/Kconfig"
2076
2077source "drivers/firmware/Kconfig"
2078
2079source "fs/Kconfig"
2080
2081source "arch/x86/Kconfig.debug"
2082
2083source "security/Kconfig"
2084
2085source "crypto/Kconfig"
2086
2087source "arch/x86/kvm/Kconfig"
2088
2089source "lib/Kconfig"
2090