xref: /linux/arch/x86/Kconfig (revision a0b54e256d513ed99e456bea6e4e188ff92e7c46)
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_COUNTERS 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 FAST_CMPXCHG_LOCAL
90	bool
91	default y
92
93config MMU
94	def_bool y
95
96config ZONE_DMA
97	def_bool y
98
99config SBUS
100	bool
101
102config GENERIC_ISA_DMA
103	def_bool y
104
105config GENERIC_IOMAP
106	def_bool y
107
108config GENERIC_BUG
109	def_bool y
110	depends on BUG
111	select GENERIC_BUG_RELATIVE_POINTERS if X86_64
112
113config GENERIC_BUG_RELATIVE_POINTERS
114	bool
115
116config GENERIC_HWEIGHT
117	def_bool y
118
119config GENERIC_GPIO
120	bool
121
122config ARCH_MAY_HAVE_PC_FDC
123	def_bool y
124
125config RWSEM_GENERIC_SPINLOCK
126	def_bool !X86_XADD
127
128config RWSEM_XCHGADD_ALGORITHM
129	def_bool X86_XADD
130
131config ARCH_HAS_CPU_IDLE_WAIT
132	def_bool y
133
134config GENERIC_CALIBRATE_DELAY
135	def_bool y
136
137config GENERIC_TIME_VSYSCALL
138	bool
139	default X86_64
140
141config ARCH_HAS_CPU_RELAX
142	def_bool y
143
144config ARCH_HAS_DEFAULT_IDLE
145	def_bool y
146
147config ARCH_HAS_CACHE_LINE_SIZE
148	def_bool y
149
150config HAVE_SETUP_PER_CPU_AREA
151	def_bool y
152
153config NEED_PER_CPU_EMBED_FIRST_CHUNK
154	def_bool y
155
156config NEED_PER_CPU_PAGE_FIRST_CHUNK
157	def_bool y
158
159config HAVE_CPUMASK_OF_CPU_MAP
160	def_bool X86_64_SMP
161
162config ARCH_HIBERNATION_POSSIBLE
163	def_bool y
164
165config ARCH_SUSPEND_POSSIBLE
166	def_bool y
167
168config ZONE_DMA32
169	bool
170	default X86_64
171
172config ARCH_POPULATES_NODE_MAP
173	def_bool y
174
175config AUDIT_ARCH
176	bool
177	default X86_64
178
179config ARCH_SUPPORTS_OPTIMIZED_INLINING
180	def_bool y
181
182config ARCH_SUPPORTS_DEBUG_PAGEALLOC
183	def_bool y
184
185config HAVE_INTEL_TXT
186	def_bool y
187	depends on EXPERIMENTAL && DMAR && ACPI
188
189# Use the generic interrupt handling code in kernel/irq/:
190config GENERIC_HARDIRQS
191	bool
192	default y
193
194config GENERIC_HARDIRQS_NO__DO_IRQ
195       def_bool y
196
197config GENERIC_IRQ_PROBE
198	bool
199	default y
200
201config GENERIC_PENDING_IRQ
202	bool
203	depends on GENERIC_HARDIRQS && SMP
204	default y
205
206config USE_GENERIC_SMP_HELPERS
207	def_bool y
208	depends on SMP
209
210config X86_32_SMP
211	def_bool y
212	depends on X86_32 && SMP
213
214config X86_64_SMP
215	def_bool y
216	depends on X86_64 && SMP
217
218config X86_HT
219	bool
220	depends on SMP
221	default y
222
223config X86_TRAMPOLINE
224	bool
225	depends on SMP || (64BIT && ACPI_SLEEP)
226	default y
227
228config X86_32_LAZY_GS
229	def_bool y
230	depends on X86_32 && !CC_STACKPROTECTOR
231
232config KTIME_SCALAR
233	def_bool X86_32
234source "init/Kconfig"
235source "kernel/Kconfig.freezer"
236
237menu "Processor type and features"
238
239source "kernel/time/Kconfig"
240
241config SMP
242	bool "Symmetric multi-processing support"
243	---help---
244	  This enables support for systems with more than one CPU. If you have
245	  a system with only one CPU, like most personal computers, say N. If
246	  you have a system with more than one CPU, say Y.
247
248	  If you say N here, the kernel will run on single and multiprocessor
249	  machines, but will use only one CPU of a multiprocessor machine. If
250	  you say Y here, the kernel will run on many, but not all,
251	  singleprocessor machines. On a singleprocessor machine, the kernel
252	  will run faster if you say N here.
253
254	  Note that if you say Y here and choose architecture "586" or
255	  "Pentium" under "Processor family", the kernel will not work on 486
256	  architectures. Similarly, multiprocessor kernels for the "PPro"
257	  architecture may not work on all Pentium based boards.
258
259	  People using multiprocessor machines who say Y here should also say
260	  Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
261	  Management" code will be disabled if you say Y here.
262
263	  See also <file:Documentation/i386/IO-APIC.txt>,
264	  <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
265	  <http://www.tldp.org/docs.html#howto>.
266
267	  If you don't know what to do here, say N.
268
269config X86_X2APIC
270	bool "Support x2apic"
271	depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
272	---help---
273	  This enables x2apic support on CPUs that have this feature.
274
275	  This allows 32-bit apic IDs (so it can support very large systems),
276	  and accesses the local apic via MSRs not via mmio.
277
278	  If you don't know what to do here, say N.
279
280config SPARSE_IRQ
281	bool "Support sparse irq numbering"
282	depends on PCI_MSI || HT_IRQ
283	---help---
284	  This enables support for sparse irqs. This is useful for distro
285	  kernels that want to define a high CONFIG_NR_CPUS value but still
286	  want to have low kernel memory footprint on smaller machines.
287
288	  ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
289	    out the irq_desc[] array in a more NUMA-friendly way. )
290
291	  If you don't know what to do here, say N.
292
293config NUMA_IRQ_DESC
294	def_bool y
295	depends on SPARSE_IRQ && NUMA
296
297config X86_MPPARSE
298	bool "Enable MPS table" if ACPI
299	default y
300	depends on X86_LOCAL_APIC
301	---help---
302	  For old smp systems that do not have proper acpi support. Newer systems
303	  (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
304
305config X86_BIGSMP
306	bool "Support for big SMP systems with more than 8 CPUs"
307	depends on X86_32 && SMP
308	---help---
309	  This option is needed for the systems that have more than 8 CPUs
310
311if X86_32
312config X86_EXTENDED_PLATFORM
313	bool "Support for extended (non-PC) x86 platforms"
314	default y
315	---help---
316	  If you disable this option then the kernel will only support
317	  standard PC platforms. (which covers the vast majority of
318	  systems out there.)
319
320	  If you enable this option then you'll be able to select support
321	  for the following (non-PC) 32 bit x86 platforms:
322		AMD Elan
323		NUMAQ (IBM/Sequent)
324		RDC R-321x SoC
325		SGI 320/540 (Visual Workstation)
326		Summit/EXA (IBM x440)
327		Unisys ES7000 IA32 series
328
329	  If you have one of these systems, or if you want to build a
330	  generic distribution kernel, say Y here - otherwise say N.
331endif
332
333if X86_64
334config X86_EXTENDED_PLATFORM
335	bool "Support for extended (non-PC) x86 platforms"
336	default y
337	---help---
338	  If you disable this option then the kernel will only support
339	  standard PC platforms. (which covers the vast majority of
340	  systems out there.)
341
342	  If you enable this option then you'll be able to select support
343	  for the following (non-PC) 64 bit x86 platforms:
344		ScaleMP vSMP
345		SGI Ultraviolet
346
347	  If you have one of these systems, or if you want to build a
348	  generic distribution kernel, say Y here - otherwise say N.
349endif
350# This is an alphabetically sorted list of 64 bit extended platforms
351# Please maintain the alphabetic order if and when there are additions
352
353config X86_VSMP
354	bool "ScaleMP vSMP"
355	select PARAVIRT
356	depends on X86_64 && PCI
357	depends on X86_EXTENDED_PLATFORM
358	---help---
359	  Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
360	  supposed to run on these EM64T-based machines.  Only choose this option
361	  if you have one of these machines.
362
363config X86_UV
364	bool "SGI Ultraviolet"
365	depends on X86_64
366	depends on X86_EXTENDED_PLATFORM
367	depends on NUMA
368	depends on X86_X2APIC
369	---help---
370	  This option is needed in order to support SGI Ultraviolet systems.
371	  If you don't have one of these, you should say N here.
372
373# Following is an alphabetically sorted list of 32 bit extended platforms
374# Please maintain the alphabetic order if and when there are additions
375
376config X86_ELAN
377	bool "AMD Elan"
378	depends on X86_32
379	depends on X86_EXTENDED_PLATFORM
380	---help---
381	  Select this for an AMD Elan processor.
382
383	  Do not use this option for K6/Athlon/Opteron processors!
384
385	  If unsure, choose "PC-compatible" instead.
386
387config X86_RDC321X
388	bool "RDC R-321x SoC"
389	depends on X86_32
390	depends on X86_EXTENDED_PLATFORM
391	select M486
392	select X86_REBOOTFIXUPS
393	---help---
394	  This option is needed for RDC R-321x system-on-chip, also known
395	  as R-8610-(G).
396	  If you don't have one of these chips, you should say N here.
397
398config X86_32_NON_STANDARD
399	bool "Support non-standard 32-bit SMP architectures"
400	depends on X86_32 && SMP
401	depends on X86_EXTENDED_PLATFORM
402	---help---
403	  This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
404	  subarchitectures.  It is intended for a generic binary kernel.
405	  if you select them all, kernel will probe it one by one. and will
406	  fallback to default.
407
408# Alphabetically sorted list of Non standard 32 bit platforms
409
410config X86_NUMAQ
411	bool "NUMAQ (IBM/Sequent)"
412	depends on X86_32_NON_STANDARD
413	select NUMA
414	select X86_MPPARSE
415	---help---
416	  This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
417	  NUMA multiquad box. This changes the way that processors are
418	  bootstrapped, and uses Clustered Logical APIC addressing mode instead
419	  of Flat Logical.  You will need a new lynxer.elf file to flash your
420	  firmware with - send email to <Martin.Bligh@us.ibm.com>.
421
422config X86_VISWS
423	bool "SGI 320/540 (Visual Workstation)"
424	depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
425	depends on X86_32_NON_STANDARD
426	---help---
427	  The SGI Visual Workstation series is an IA32-based workstation
428	  based on SGI systems chips with some legacy PC hardware attached.
429
430	  Say Y here to create a kernel to run on the SGI 320 or 540.
431
432	  A kernel compiled for the Visual Workstation will run on general
433	  PCs as well. See <file:Documentation/sgi-visws.txt> for details.
434
435config X86_SUMMIT
436	bool "Summit/EXA (IBM x440)"
437	depends on X86_32_NON_STANDARD
438	---help---
439	  This option is needed for IBM systems that use the Summit/EXA chipset.
440	  In particular, it is needed for the x440.
441
442config X86_ES7000
443	bool "Unisys ES7000 IA32 series"
444	depends on X86_32_NON_STANDARD && X86_BIGSMP
445	---help---
446	  Support for Unisys ES7000 systems.  Say 'Y' here if this kernel is
447	  supposed to run on an IA32-based Unisys ES7000 system.
448
449config SCHED_OMIT_FRAME_POINTER
450	def_bool y
451	prompt "Single-depth WCHAN output"
452	depends on X86
453	---help---
454	  Calculate simpler /proc/<PID>/wchan values. If this option
455	  is disabled then wchan values will recurse back to the
456	  caller function. This provides more accurate wchan values,
457	  at the expense of slightly more scheduling overhead.
458
459	  If in doubt, say "Y".
460
461menuconfig PARAVIRT_GUEST
462	bool "Paravirtualized guest support"
463	---help---
464	  Say Y here to get to see options related to running Linux under
465	  various hypervisors.  This option alone does not add any kernel code.
466
467	  If you say N, all options in this submenu will be skipped and disabled.
468
469if PARAVIRT_GUEST
470
471source "arch/x86/xen/Kconfig"
472
473config VMI
474	bool "VMI Guest support"
475	select PARAVIRT
476	depends on X86_32
477	---help---
478	  VMI provides a paravirtualized interface to the VMware ESX server
479	  (it could be used by other hypervisors in theory too, but is not
480	  at the moment), by linking the kernel to a GPL-ed ROM module
481	  provided by the hypervisor.
482
483config KVM_CLOCK
484	bool "KVM paravirtualized clock"
485	select PARAVIRT
486	select PARAVIRT_CLOCK
487	---help---
488	  Turning on this option will allow you to run a paravirtualized clock
489	  when running over the KVM hypervisor. Instead of relying on a PIT
490	  (or probably other) emulation by the underlying device model, the host
491	  provides the guest with timing infrastructure such as time of day, and
492	  system time
493
494config KVM_GUEST
495	bool "KVM Guest support"
496	select PARAVIRT
497	---help---
498	  This option enables various optimizations for running under the KVM
499	  hypervisor.
500
501source "arch/x86/lguest/Kconfig"
502
503config PARAVIRT
504	bool "Enable paravirtualization code"
505	---help---
506	  This changes the kernel so it can modify itself when it is run
507	  under a hypervisor, potentially improving performance significantly
508	  over full virtualization.  However, when run without a hypervisor
509	  the kernel is theoretically slower and slightly larger.
510
511config PARAVIRT_SPINLOCKS
512	bool "Paravirtualization layer for spinlocks"
513	depends on PARAVIRT && SMP && EXPERIMENTAL
514	---help---
515	  Paravirtualized spinlocks allow a pvops backend to replace the
516	  spinlock implementation with something virtualization-friendly
517	  (for example, block the virtual CPU rather than spinning).
518
519	  Unfortunately the downside is an up to 5% performance hit on
520	  native kernels, with various workloads.
521
522	  If you are unsure how to answer this question, answer N.
523
524config PARAVIRT_CLOCK
525	bool
526	default n
527
528endif
529
530config PARAVIRT_DEBUG
531	bool "paravirt-ops debugging"
532	depends on PARAVIRT && DEBUG_KERNEL
533	---help---
534	  Enable to debug paravirt_ops internals.  Specifically, BUG if
535	  a paravirt_op is missing when it is called.
536
537config MEMTEST
538	bool "Memtest"
539	---help---
540	  This option adds a kernel parameter 'memtest', which allows memtest
541	  to be set.
542	        memtest=0, mean disabled; -- default
543	        memtest=1, mean do 1 test pattern;
544	        ...
545	        memtest=4, mean do 4 test patterns.
546	  If you are unsure how to answer this question, answer N.
547
548config X86_SUMMIT_NUMA
549	def_bool y
550	depends on X86_32 && NUMA && X86_32_NON_STANDARD
551
552config X86_CYCLONE_TIMER
553	def_bool y
554	depends on X86_32_NON_STANDARD
555
556source "arch/x86/Kconfig.cpu"
557
558config HPET_TIMER
559	def_bool X86_64
560	prompt "HPET Timer Support" if X86_32
561	---help---
562	  Use the IA-PC HPET (High Precision Event Timer) to manage
563	  time in preference to the PIT and RTC, if a HPET is
564	  present.
565	  HPET is the next generation timer replacing legacy 8254s.
566	  The HPET provides a stable time base on SMP
567	  systems, unlike the TSC, but it is more expensive to access,
568	  as it is off-chip.  You can find the HPET spec at
569	  <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
570
571	  You can safely choose Y here.  However, HPET will only be
572	  activated if the platform and the BIOS support this feature.
573	  Otherwise the 8254 will be used for timing services.
574
575	  Choose N to continue using the legacy 8254 timer.
576
577config HPET_EMULATE_RTC
578	def_bool y
579	depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
580
581# Mark as embedded because too many people got it wrong.
582# The code disables itself when not needed.
583config DMI
584	default y
585	bool "Enable DMI scanning" if EMBEDDED
586	---help---
587	  Enabled scanning of DMI to identify machine quirks. Say Y
588	  here unless you have verified that your setup is not
589	  affected by entries in the DMI blacklist. Required by PNP
590	  BIOS code.
591
592config GART_IOMMU
593	bool "GART IOMMU support" if EMBEDDED
594	default y
595	select SWIOTLB
596	depends on X86_64 && PCI
597	---help---
598	  Support for full DMA access of devices with 32bit memory access only
599	  on systems with more than 3GB. This is usually needed for USB,
600	  sound, many IDE/SATA chipsets and some other devices.
601	  Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
602	  based hardware IOMMU and a software bounce buffer based IOMMU used
603	  on Intel systems and as fallback.
604	  The code is only active when needed (enough memory and limited
605	  device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
606	  too.
607
608config CALGARY_IOMMU
609	bool "IBM Calgary IOMMU support"
610	select SWIOTLB
611	depends on X86_64 && PCI && EXPERIMENTAL
612	---help---
613	  Support for hardware IOMMUs in IBM's xSeries x366 and x460
614	  systems. Needed to run systems with more than 3GB of memory
615	  properly with 32-bit PCI devices that do not support DAC
616	  (Double Address Cycle). Calgary also supports bus level
617	  isolation, where all DMAs pass through the IOMMU.  This
618	  prevents them from going anywhere except their intended
619	  destination. This catches hard-to-find kernel bugs and
620	  mis-behaving drivers and devices that do not use the DMA-API
621	  properly to set up their DMA buffers.  The IOMMU can be
622	  turned off at boot time with the iommu=off parameter.
623	  Normally the kernel will make the right choice by itself.
624	  If unsure, say Y.
625
626config CALGARY_IOMMU_ENABLED_BY_DEFAULT
627	def_bool y
628	prompt "Should Calgary be enabled by default?"
629	depends on CALGARY_IOMMU
630	---help---
631	  Should Calgary be enabled by default? if you choose 'y', Calgary
632	  will be used (if it exists). If you choose 'n', Calgary will not be
633	  used even if it exists. If you choose 'n' and would like to use
634	  Calgary anyway, pass 'iommu=calgary' on the kernel command line.
635	  If unsure, say Y.
636
637config AMD_IOMMU
638	bool "AMD IOMMU support"
639	select SWIOTLB
640	select PCI_MSI
641	depends on X86_64 && PCI && ACPI
642	---help---
643	  With this option you can enable support for AMD IOMMU hardware in
644	  your system. An IOMMU is a hardware component which provides
645	  remapping of DMA memory accesses from devices. With an AMD IOMMU you
646	  can isolate the the DMA memory of different devices and protect the
647	  system from misbehaving device drivers or hardware.
648
649	  You can find out if your system has an AMD IOMMU if you look into
650	  your BIOS for an option to enable it or if you have an IVRS ACPI
651	  table.
652
653config AMD_IOMMU_STATS
654	bool "Export AMD IOMMU statistics to debugfs"
655	depends on AMD_IOMMU
656	select DEBUG_FS
657	---help---
658	  This option enables code in the AMD IOMMU driver to collect various
659	  statistics about whats happening in the driver and exports that
660	  information to userspace via debugfs.
661	  If unsure, say N.
662
663# need this always selected by IOMMU for the VIA workaround
664config SWIOTLB
665	def_bool y if X86_64
666	---help---
667	  Support for software bounce buffers used on x86-64 systems
668	  which don't have a hardware IOMMU (e.g. the current generation
669	  of Intel's x86-64 CPUs). Using this PCI devices which can only
670	  access 32-bits of memory can be used on systems with more than
671	  3 GB of memory. If unsure, say Y.
672
673config IOMMU_HELPER
674	def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
675
676config IOMMU_API
677	def_bool (AMD_IOMMU || DMAR)
678
679config MAXSMP
680	bool "Configure Maximum number of SMP Processors and NUMA Nodes"
681	depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
682	select CPUMASK_OFFSTACK
683	default n
684	---help---
685	  Configure maximum number of CPUS and NUMA Nodes for this architecture.
686	  If unsure, say N.
687
688config NR_CPUS
689	int "Maximum number of CPUs" if SMP && !MAXSMP
690	range 2 8 if SMP && X86_32 && !X86_BIGSMP
691	range 2 512 if SMP && !MAXSMP
692	default "1" if !SMP
693	default "4096" if MAXSMP
694	default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
695	default "8" if SMP
696	---help---
697	  This allows you to specify the maximum number of CPUs which this
698	  kernel will support.  The maximum supported value is 512 and the
699	  minimum value which makes sense is 2.
700
701	  This is purely to save memory - each supported CPU adds
702	  approximately eight kilobytes to the kernel image.
703
704config SCHED_SMT
705	bool "SMT (Hyperthreading) scheduler support"
706	depends on X86_HT
707	---help---
708	  SMT scheduler support improves the CPU scheduler's decision making
709	  when dealing with Intel Pentium 4 chips with HyperThreading at a
710	  cost of slightly increased overhead in some places. If unsure say
711	  N here.
712
713config SCHED_MC
714	def_bool y
715	prompt "Multi-core scheduler support"
716	depends on X86_HT
717	---help---
718	  Multi-core scheduler support improves the CPU scheduler's decision
719	  making when dealing with multi-core CPU chips at a cost of slightly
720	  increased overhead in some places. If unsure say N here.
721
722source "kernel/Kconfig.preempt"
723
724config X86_UP_APIC
725	bool "Local APIC support on uniprocessors"
726	depends on X86_32 && !SMP && !X86_32_NON_STANDARD
727	---help---
728	  A local APIC (Advanced Programmable Interrupt Controller) is an
729	  integrated interrupt controller in the CPU. If you have a single-CPU
730	  system which has a processor with a local APIC, you can say Y here to
731	  enable and use it. If you say Y here even though your machine doesn't
732	  have a local APIC, then the kernel will still run with no slowdown at
733	  all. The local APIC supports CPU-generated self-interrupts (timer,
734	  performance counters), and the NMI watchdog which detects hard
735	  lockups.
736
737config X86_UP_IOAPIC
738	bool "IO-APIC support on uniprocessors"
739	depends on X86_UP_APIC
740	---help---
741	  An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
742	  SMP-capable replacement for PC-style interrupt controllers. Most
743	  SMP systems and many recent uniprocessor systems have one.
744
745	  If you have a single-CPU system with an IO-APIC, you can say Y here
746	  to use it. If you say Y here even though your machine doesn't have
747	  an IO-APIC, then the kernel will still run with no slowdown at all.
748
749config X86_LOCAL_APIC
750	def_bool y
751	depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
752
753config X86_IO_APIC
754	def_bool y
755	depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
756
757config X86_VISWS_APIC
758	def_bool y
759	depends on X86_32 && X86_VISWS
760
761config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
762	bool "Reroute for broken boot IRQs"
763	default n
764	depends on X86_IO_APIC
765	---help---
766	  This option enables a workaround that fixes a source of
767	  spurious interrupts. This is recommended when threaded
768	  interrupt handling is used on systems where the generation of
769	  superfluous "boot interrupts" cannot be disabled.
770
771	  Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
772	  entry in the chipset's IO-APIC is masked (as, e.g. the RT
773	  kernel does during interrupt handling). On chipsets where this
774	  boot IRQ generation cannot be disabled, this workaround keeps
775	  the original IRQ line masked so that only the equivalent "boot
776	  IRQ" is delivered to the CPUs. The workaround also tells the
777	  kernel to set up the IRQ handler on the boot IRQ line. In this
778	  way only one interrupt is delivered to the kernel. Otherwise
779	  the spurious second interrupt may cause the kernel to bring
780	  down (vital) interrupt lines.
781
782	  Only affects "broken" chipsets. Interrupt sharing may be
783	  increased on these systems.
784
785config X86_MCE
786	bool "Machine Check Exception"
787	---help---
788	  Machine Check Exception support allows the processor to notify the
789	  kernel if it detects a problem (e.g. overheating, component failure).
790	  The action the kernel takes depends on the severity of the problem,
791	  ranging from a warning message on the console, to halting the machine.
792	  Your processor must be a Pentium or newer to support this - check the
793	  flags in /proc/cpuinfo for mce.  Note that some older Pentium systems
794	  have a design flaw which leads to false MCE events - hence MCE is
795	  disabled on all P5 processors, unless explicitly enabled with "mce"
796	  as a boot argument.  Similarly, if MCE is built in and creates a
797	  problem on some new non-standard machine, you can boot with "nomce"
798	  to disable it.  MCE support simply ignores non-MCE processors like
799	  the 386 and 486, so nearly everyone can say Y here.
800
801config X86_OLD_MCE
802	depends on X86_32 && X86_MCE
803	bool "Use legacy machine check code (will go away)"
804	default n
805	select X86_ANCIENT_MCE
806	---help---
807	  Use the old i386 machine check code. This is merely intended for
808	  testing in a transition period. Try this if you run into any machine
809	  check related software problems, but report the problem to
810	  linux-kernel.  When in doubt say no.
811
812config X86_NEW_MCE
813	depends on X86_MCE
814	bool
815	default y if (!X86_OLD_MCE && X86_32) || X86_64
816
817config X86_MCE_INTEL
818	def_bool y
819	prompt "Intel MCE features"
820	depends on X86_NEW_MCE && X86_LOCAL_APIC
821	---help---
822	   Additional support for intel specific MCE features such as
823	   the thermal monitor.
824
825config X86_MCE_AMD
826	def_bool y
827	prompt "AMD MCE features"
828	depends on X86_NEW_MCE && X86_LOCAL_APIC
829	---help---
830	   Additional support for AMD specific MCE features such as
831	   the DRAM Error Threshold.
832
833config X86_ANCIENT_MCE
834	def_bool n
835	depends on X86_32
836	prompt "Support for old Pentium 5 / WinChip machine checks"
837	---help---
838	  Include support for machine check handling on old Pentium 5 or WinChip
839	  systems. These typically need to be enabled explicitely on the command
840	  line.
841
842config X86_MCE_THRESHOLD
843	depends on X86_MCE_AMD || X86_MCE_INTEL
844	bool
845	default y
846
847config X86_MCE_INJECT
848	depends on X86_NEW_MCE
849	tristate "Machine check injector support"
850	---help---
851	  Provide support for injecting machine checks for testing purposes.
852	  If you don't know what a machine check is and you don't do kernel
853	  QA it is safe to say n.
854
855config X86_MCE_NONFATAL
856	tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
857	depends on X86_OLD_MCE
858	---help---
859	  Enabling this feature starts a timer that triggers every 5 seconds which
860	  will look at the machine check registers to see if anything happened.
861	  Non-fatal problems automatically get corrected (but still logged).
862	  Disable this if you don't want to see these messages.
863	  Seeing the messages this option prints out may be indicative of dying
864	  or out-of-spec (ie, overclocked) hardware.
865	  This option only does something on certain CPUs.
866	  (AMD Athlon/Duron and Intel Pentium 4)
867
868config X86_MCE_P4THERMAL
869	bool "check for P4 thermal throttling interrupt."
870	depends on X86_OLD_MCE && X86_MCE && (X86_UP_APIC || SMP)
871	---help---
872	  Enabling this feature will cause a message to be printed when the P4
873	  enters thermal throttling.
874
875config X86_THERMAL_VECTOR
876	def_bool y
877	depends on X86_MCE_P4THERMAL || X86_MCE_INTEL
878
879config VM86
880	bool "Enable VM86 support" if EMBEDDED
881	default y
882	depends on X86_32
883	---help---
884	  This option is required by programs like DOSEMU to run 16-bit legacy
885	  code on X86 processors. It also may be needed by software like
886	  XFree86 to initialize some video cards via BIOS. Disabling this
887	  option saves about 6k.
888
889config TOSHIBA
890	tristate "Toshiba Laptop support"
891	depends on X86_32
892	---help---
893	  This adds a driver to safely access the System Management Mode of
894	  the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
895	  not work on models with a Phoenix BIOS. The System Management Mode
896	  is used to set the BIOS and power saving options on Toshiba portables.
897
898	  For information on utilities to make use of this driver see the
899	  Toshiba Linux utilities web site at:
900	  <http://www.buzzard.org.uk/toshiba/>.
901
902	  Say Y if you intend to run this kernel on a Toshiba portable.
903	  Say N otherwise.
904
905config I8K
906	tristate "Dell laptop support"
907	---help---
908	  This adds a driver to safely access the System Management Mode
909	  of the CPU on the Dell Inspiron 8000. The System Management Mode
910	  is used to read cpu temperature and cooling fan status and to
911	  control the fans on the I8K portables.
912
913	  This driver has been tested only on the Inspiron 8000 but it may
914	  also work with other Dell laptops. You can force loading on other
915	  models by passing the parameter `force=1' to the module. Use at
916	  your own risk.
917
918	  For information on utilities to make use of this driver see the
919	  I8K Linux utilities web site at:
920	  <http://people.debian.org/~dz/i8k/>
921
922	  Say Y if you intend to run this kernel on a Dell Inspiron 8000.
923	  Say N otherwise.
924
925config X86_REBOOTFIXUPS
926	bool "Enable X86 board specific fixups for reboot"
927	depends on X86_32
928	---help---
929	  This enables chipset and/or board specific fixups to be done
930	  in order to get reboot to work correctly. This is only needed on
931	  some combinations of hardware and BIOS. The symptom, for which
932	  this config is intended, is when reboot ends with a stalled/hung
933	  system.
934
935	  Currently, the only fixup is for the Geode machines using
936	  CS5530A and CS5536 chipsets and the RDC R-321x SoC.
937
938	  Say Y if you want to enable the fixup. Currently, it's safe to
939	  enable this option even if you don't need it.
940	  Say N otherwise.
941
942config MICROCODE
943	tristate "/dev/cpu/microcode - microcode support"
944	select FW_LOADER
945	---help---
946	  If you say Y here, you will be able to update the microcode on
947	  certain Intel and AMD processors. The Intel support is for the
948	  IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
949	  Pentium 4, Xeon etc. The AMD support is for family 0x10 and
950	  0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
951	  You will obviously need the actual microcode binary data itself
952	  which is not shipped with the Linux kernel.
953
954	  This option selects the general module only, you need to select
955	  at least one vendor specific module as well.
956
957	  To compile this driver as a module, choose M here: the
958	  module will be called microcode.
959
960config MICROCODE_INTEL
961	bool "Intel microcode patch loading support"
962	depends on MICROCODE
963	default MICROCODE
964	select FW_LOADER
965	---help---
966	  This options enables microcode patch loading support for Intel
967	  processors.
968
969	  For latest news and information on obtaining all the required
970	  Intel ingredients for this driver, check:
971	  <http://www.urbanmyth.org/microcode/>.
972
973config MICROCODE_AMD
974	bool "AMD microcode patch loading support"
975	depends on MICROCODE
976	select FW_LOADER
977	---help---
978	  If you select this option, microcode patch loading support for AMD
979	  processors will be enabled.
980
981config MICROCODE_OLD_INTERFACE
982	def_bool y
983	depends on MICROCODE
984
985config X86_MSR
986	tristate "/dev/cpu/*/msr - Model-specific register support"
987	---help---
988	  This device gives privileged processes access to the x86
989	  Model-Specific Registers (MSRs).  It is a character device with
990	  major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
991	  MSR accesses are directed to a specific CPU on multi-processor
992	  systems.
993
994config X86_CPUID
995	tristate "/dev/cpu/*/cpuid - CPU information support"
996	---help---
997	  This device gives processes access to the x86 CPUID instruction to
998	  be executed on a specific processor.  It is a character device
999	  with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1000	  /dev/cpu/31/cpuid.
1001
1002config X86_CPU_DEBUG
1003	tristate "/sys/kernel/debug/x86/cpu/* - CPU Debug support"
1004	---help---
1005	  If you select this option, this will provide various x86 CPUs
1006	  information through debugfs.
1007
1008choice
1009	prompt "High Memory Support"
1010	default HIGHMEM4G if !X86_NUMAQ
1011	default HIGHMEM64G if X86_NUMAQ
1012	depends on X86_32
1013
1014config NOHIGHMEM
1015	bool "off"
1016	depends on !X86_NUMAQ
1017	---help---
1018	  Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1019	  However, the address space of 32-bit x86 processors is only 4
1020	  Gigabytes large. That means that, if you have a large amount of
1021	  physical memory, not all of it can be "permanently mapped" by the
1022	  kernel. The physical memory that's not permanently mapped is called
1023	  "high memory".
1024
1025	  If you are compiling a kernel which will never run on a machine with
1026	  more than 1 Gigabyte total physical RAM, answer "off" here (default
1027	  choice and suitable for most users). This will result in a "3GB/1GB"
1028	  split: 3GB are mapped so that each process sees a 3GB virtual memory
1029	  space and the remaining part of the 4GB virtual memory space is used
1030	  by the kernel to permanently map as much physical memory as
1031	  possible.
1032
1033	  If the machine has between 1 and 4 Gigabytes physical RAM, then
1034	  answer "4GB" here.
1035
1036	  If more than 4 Gigabytes is used then answer "64GB" here. This
1037	  selection turns Intel PAE (Physical Address Extension) mode on.
1038	  PAE implements 3-level paging on IA32 processors. PAE is fully
1039	  supported by Linux, PAE mode is implemented on all recent Intel
1040	  processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1041	  then the kernel will not boot on CPUs that don't support PAE!
1042
1043	  The actual amount of total physical memory will either be
1044	  auto detected or can be forced by using a kernel command line option
1045	  such as "mem=256M". (Try "man bootparam" or see the documentation of
1046	  your boot loader (lilo or loadlin) about how to pass options to the
1047	  kernel at boot time.)
1048
1049	  If unsure, say "off".
1050
1051config HIGHMEM4G
1052	bool "4GB"
1053	depends on !X86_NUMAQ
1054	---help---
1055	  Select this if you have a 32-bit processor and between 1 and 4
1056	  gigabytes of physical RAM.
1057
1058config HIGHMEM64G
1059	bool "64GB"
1060	depends on !M386 && !M486
1061	select X86_PAE
1062	---help---
1063	  Select this if you have a 32-bit processor and more than 4
1064	  gigabytes of physical RAM.
1065
1066endchoice
1067
1068choice
1069	depends on EXPERIMENTAL
1070	prompt "Memory split" if EMBEDDED
1071	default VMSPLIT_3G
1072	depends on X86_32
1073	---help---
1074	  Select the desired split between kernel and user memory.
1075
1076	  If the address range available to the kernel is less than the
1077	  physical memory installed, the remaining memory will be available
1078	  as "high memory". Accessing high memory is a little more costly
1079	  than low memory, as it needs to be mapped into the kernel first.
1080	  Note that increasing the kernel address space limits the range
1081	  available to user programs, making the address space there
1082	  tighter.  Selecting anything other than the default 3G/1G split
1083	  will also likely make your kernel incompatible with binary-only
1084	  kernel modules.
1085
1086	  If you are not absolutely sure what you are doing, leave this
1087	  option alone!
1088
1089	config VMSPLIT_3G
1090		bool "3G/1G user/kernel split"
1091	config VMSPLIT_3G_OPT
1092		depends on !X86_PAE
1093		bool "3G/1G user/kernel split (for full 1G low memory)"
1094	config VMSPLIT_2G
1095		bool "2G/2G user/kernel split"
1096	config VMSPLIT_2G_OPT
1097		depends on !X86_PAE
1098		bool "2G/2G user/kernel split (for full 2G low memory)"
1099	config VMSPLIT_1G
1100		bool "1G/3G user/kernel split"
1101endchoice
1102
1103config PAGE_OFFSET
1104	hex
1105	default 0xB0000000 if VMSPLIT_3G_OPT
1106	default 0x80000000 if VMSPLIT_2G
1107	default 0x78000000 if VMSPLIT_2G_OPT
1108	default 0x40000000 if VMSPLIT_1G
1109	default 0xC0000000
1110	depends on X86_32
1111
1112config HIGHMEM
1113	def_bool y
1114	depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1115
1116config X86_PAE
1117	bool "PAE (Physical Address Extension) Support"
1118	depends on X86_32 && !HIGHMEM4G
1119	---help---
1120	  PAE is required for NX support, and furthermore enables
1121	  larger swapspace support for non-overcommit purposes. It
1122	  has the cost of more pagetable lookup overhead, and also
1123	  consumes more pagetable space per process.
1124
1125config ARCH_PHYS_ADDR_T_64BIT
1126	def_bool X86_64 || X86_PAE
1127
1128config DIRECT_GBPAGES
1129	bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
1130	default y
1131	depends on X86_64
1132	---help---
1133	  Allow the kernel linear mapping to use 1GB pages on CPUs that
1134	  support it. This can improve the kernel's performance a tiny bit by
1135	  reducing TLB pressure. If in doubt, say "Y".
1136
1137# Common NUMA Features
1138config NUMA
1139	bool "Numa Memory Allocation and Scheduler Support"
1140	depends on SMP
1141	depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1142	default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1143	---help---
1144	  Enable NUMA (Non Uniform Memory Access) support.
1145
1146	  The kernel will try to allocate memory used by a CPU on the
1147	  local memory controller of the CPU and add some more
1148	  NUMA awareness to the kernel.
1149
1150	  For 64-bit this is recommended if the system is Intel Core i7
1151	  (or later), AMD Opteron, or EM64T NUMA.
1152
1153	  For 32-bit this is only needed on (rare) 32-bit-only platforms
1154	  that support NUMA topologies, such as NUMAQ / Summit, or if you
1155	  boot a 32-bit kernel on a 64-bit NUMA platform.
1156
1157	  Otherwise, you should say N.
1158
1159comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1160	depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1161
1162config K8_NUMA
1163	def_bool y
1164	prompt "Old style AMD Opteron NUMA detection"
1165	depends on X86_64 && NUMA && PCI
1166	---help---
1167	  Enable K8 NUMA node topology detection.  You should say Y here if
1168	  you have a multi processor AMD K8 system. This uses an old
1169	  method to read the NUMA configuration directly from the builtin
1170	  Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
1171	  instead, which also takes priority if both are compiled in.
1172
1173config X86_64_ACPI_NUMA
1174	def_bool y
1175	prompt "ACPI NUMA detection"
1176	depends on X86_64 && NUMA && ACPI && PCI
1177	select ACPI_NUMA
1178	---help---
1179	  Enable ACPI SRAT based node topology detection.
1180
1181# Some NUMA nodes have memory ranges that span
1182# other nodes.  Even though a pfn is valid and
1183# between a node's start and end pfns, it may not
1184# reside on that node.  See memmap_init_zone()
1185# for details.
1186config NODES_SPAN_OTHER_NODES
1187	def_bool y
1188	depends on X86_64_ACPI_NUMA
1189
1190config NUMA_EMU
1191	bool "NUMA emulation"
1192	depends on X86_64 && NUMA
1193	---help---
1194	  Enable NUMA emulation. A flat machine will be split
1195	  into virtual nodes when booted with "numa=fake=N", where N is the
1196	  number of nodes. This is only useful for debugging.
1197
1198config NODES_SHIFT
1199	int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1200	range 1 9
1201	default "9" if MAXSMP
1202	default "6" if X86_64
1203	default "4" if X86_NUMAQ
1204	default "3"
1205	depends on NEED_MULTIPLE_NODES
1206	---help---
1207	  Specify the maximum number of NUMA Nodes available on the target
1208	  system.  Increases memory reserved to accommodate various tables.
1209
1210config HAVE_ARCH_BOOTMEM
1211	def_bool y
1212	depends on X86_32 && NUMA
1213
1214config ARCH_HAVE_MEMORY_PRESENT
1215	def_bool y
1216	depends on X86_32 && DISCONTIGMEM
1217
1218config NEED_NODE_MEMMAP_SIZE
1219	def_bool y
1220	depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1221
1222config HAVE_ARCH_ALLOC_REMAP
1223	def_bool y
1224	depends on X86_32 && NUMA
1225
1226config ARCH_FLATMEM_ENABLE
1227	def_bool y
1228	depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
1229
1230config ARCH_DISCONTIGMEM_ENABLE
1231	def_bool y
1232	depends on NUMA && X86_32
1233
1234config ARCH_DISCONTIGMEM_DEFAULT
1235	def_bool y
1236	depends on NUMA && X86_32
1237
1238config ARCH_SPARSEMEM_DEFAULT
1239	def_bool y
1240	depends on X86_64
1241
1242config ARCH_SPARSEMEM_ENABLE
1243	def_bool y
1244	depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1245	select SPARSEMEM_STATIC if X86_32
1246	select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1247
1248config ARCH_SELECT_MEMORY_MODEL
1249	def_bool y
1250	depends on ARCH_SPARSEMEM_ENABLE
1251
1252config ARCH_MEMORY_PROBE
1253	def_bool X86_64
1254	depends on MEMORY_HOTPLUG
1255
1256source "mm/Kconfig"
1257
1258config HIGHPTE
1259	bool "Allocate 3rd-level pagetables from highmem"
1260	depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1261	---help---
1262	  The VM uses one page table entry for each page of physical memory.
1263	  For systems with a lot of RAM, this can be wasteful of precious
1264	  low memory.  Setting this option will put user-space page table
1265	  entries in high memory.
1266
1267config X86_CHECK_BIOS_CORRUPTION
1268	bool "Check for low memory corruption"
1269	---help---
1270	  Periodically check for memory corruption in low memory, which
1271	  is suspected to be caused by BIOS.  Even when enabled in the
1272	  configuration, it is disabled at runtime.  Enable it by
1273	  setting "memory_corruption_check=1" on the kernel command
1274	  line.  By default it scans the low 64k of memory every 60
1275	  seconds; see the memory_corruption_check_size and
1276	  memory_corruption_check_period parameters in
1277	  Documentation/kernel-parameters.txt to adjust this.
1278
1279	  When enabled with the default parameters, this option has
1280	  almost no overhead, as it reserves a relatively small amount
1281	  of memory and scans it infrequently.  It both detects corruption
1282	  and prevents it from affecting the running system.
1283
1284	  It is, however, intended as a diagnostic tool; if repeatable
1285	  BIOS-originated corruption always affects the same memory,
1286	  you can use memmap= to prevent the kernel from using that
1287	  memory.
1288
1289config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1290	bool "Set the default setting of memory_corruption_check"
1291	depends on X86_CHECK_BIOS_CORRUPTION
1292	default y
1293	---help---
1294	  Set whether the default state of memory_corruption_check is
1295	  on or off.
1296
1297config X86_RESERVE_LOW_64K
1298	bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
1299	default y
1300	---help---
1301	  Reserve the first 64K of physical RAM on BIOSes that are known
1302	  to potentially corrupt that memory range. A numbers of BIOSes are
1303	  known to utilize this area during suspend/resume, so it must not
1304	  be used by the kernel.
1305
1306	  Set this to N if you are absolutely sure that you trust the BIOS
1307	  to get all its memory reservations and usages right.
1308
1309	  If you have doubts about the BIOS (e.g. suspend/resume does not
1310	  work or there's kernel crashes after certain hardware hotplug
1311	  events) and it's not AMI or Phoenix, then you might want to enable
1312	  X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
1313	  corruption patterns.
1314
1315	  Say Y if unsure.
1316
1317config MATH_EMULATION
1318	bool
1319	prompt "Math emulation" if X86_32
1320	---help---
1321	  Linux can emulate a math coprocessor (used for floating point
1322	  operations) if you don't have one. 486DX and Pentium processors have
1323	  a math coprocessor built in, 486SX and 386 do not, unless you added
1324	  a 487DX or 387, respectively. (The messages during boot time can
1325	  give you some hints here ["man dmesg"].) Everyone needs either a
1326	  coprocessor or this emulation.
1327
1328	  If you don't have a math coprocessor, you need to say Y here; if you
1329	  say Y here even though you have a coprocessor, the coprocessor will
1330	  be used nevertheless. (This behavior can be changed with the kernel
1331	  command line option "no387", which comes handy if your coprocessor
1332	  is broken. Try "man bootparam" or see the documentation of your boot
1333	  loader (lilo or loadlin) about how to pass options to the kernel at
1334	  boot time.) This means that it is a good idea to say Y here if you
1335	  intend to use this kernel on different machines.
1336
1337	  More information about the internals of the Linux math coprocessor
1338	  emulation can be found in <file:arch/x86/math-emu/README>.
1339
1340	  If you are not sure, say Y; apart from resulting in a 66 KB bigger
1341	  kernel, it won't hurt.
1342
1343config MTRR
1344	bool "MTRR (Memory Type Range Register) support"
1345	---help---
1346	  On Intel P6 family processors (Pentium Pro, Pentium II and later)
1347	  the Memory Type Range Registers (MTRRs) may be used to control
1348	  processor access to memory ranges. This is most useful if you have
1349	  a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1350	  allows bus write transfers to be combined into a larger transfer
1351	  before bursting over the PCI/AGP bus. This can increase performance
1352	  of image write operations 2.5 times or more. Saying Y here creates a
1353	  /proc/mtrr file which may be used to manipulate your processor's
1354	  MTRRs. Typically the X server should use this.
1355
1356	  This code has a reasonably generic interface so that similar
1357	  control registers on other processors can be easily supported
1358	  as well:
1359
1360	  The Cyrix 6x86, 6x86MX and M II processors have Address Range
1361	  Registers (ARRs) which provide a similar functionality to MTRRs. For
1362	  these, the ARRs are used to emulate the MTRRs.
1363	  The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1364	  MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1365	  write-combining. All of these processors are supported by this code
1366	  and it makes sense to say Y here if you have one of them.
1367
1368	  Saying Y here also fixes a problem with buggy SMP BIOSes which only
1369	  set the MTRRs for the boot CPU and not for the secondary CPUs. This
1370	  can lead to all sorts of problems, so it's good to say Y here.
1371
1372	  You can safely say Y even if your machine doesn't have MTRRs, you'll
1373	  just add about 9 KB to your kernel.
1374
1375	  See <file:Documentation/x86/mtrr.txt> for more information.
1376
1377config MTRR_SANITIZER
1378	def_bool y
1379	prompt "MTRR cleanup support"
1380	depends on MTRR
1381	---help---
1382	  Convert MTRR layout from continuous to discrete, so X drivers can
1383	  add writeback entries.
1384
1385	  Can be disabled with disable_mtrr_cleanup on the kernel command line.
1386	  The largest mtrr entry size for a continuous block can be set with
1387	  mtrr_chunk_size.
1388
1389	  If unsure, say Y.
1390
1391config MTRR_SANITIZER_ENABLE_DEFAULT
1392	int "MTRR cleanup enable value (0-1)"
1393	range 0 1
1394	default "0"
1395	depends on MTRR_SANITIZER
1396	---help---
1397	  Enable mtrr cleanup default value
1398
1399config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1400	int "MTRR cleanup spare reg num (0-7)"
1401	range 0 7
1402	default "1"
1403	depends on MTRR_SANITIZER
1404	---help---
1405	  mtrr cleanup spare entries default, it can be changed via
1406	  mtrr_spare_reg_nr=N on the kernel command line.
1407
1408config X86_PAT
1409	bool
1410	prompt "x86 PAT support"
1411	depends on MTRR
1412	---help---
1413	  Use PAT attributes to setup page level cache control.
1414
1415	  PATs are the modern equivalents of MTRRs and are much more
1416	  flexible than MTRRs.
1417
1418	  Say N here if you see bootup problems (boot crash, boot hang,
1419	  spontaneous reboots) or a non-working video driver.
1420
1421	  If unsure, say Y.
1422
1423config ARCH_USES_PG_UNCACHED
1424	def_bool y
1425	depends on X86_PAT
1426
1427config EFI
1428	bool "EFI runtime service support"
1429	depends on ACPI
1430	---help---
1431	  This enables the kernel to use EFI runtime services that are
1432	  available (such as the EFI variable services).
1433
1434	  This option is only useful on systems that have EFI firmware.
1435	  In addition, you should use the latest ELILO loader available
1436	  at <http://elilo.sourceforge.net> in order to take advantage
1437	  of EFI runtime services. However, even with this option, the
1438	  resultant kernel should continue to boot on existing non-EFI
1439	  platforms.
1440
1441config SECCOMP
1442	def_bool y
1443	prompt "Enable seccomp to safely compute untrusted bytecode"
1444	---help---
1445	  This kernel feature is useful for number crunching applications
1446	  that may need to compute untrusted bytecode during their
1447	  execution. By using pipes or other transports made available to
1448	  the process as file descriptors supporting the read/write
1449	  syscalls, it's possible to isolate those applications in
1450	  their own address space using seccomp. Once seccomp is
1451	  enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1452	  and the task is only allowed to execute a few safe syscalls
1453	  defined by each seccomp mode.
1454
1455	  If unsure, say Y. Only embedded should say N here.
1456
1457config CC_STACKPROTECTOR_ALL
1458	bool
1459
1460config CC_STACKPROTECTOR
1461	bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1462	select CC_STACKPROTECTOR_ALL
1463	---help---
1464	  This option turns on the -fstack-protector GCC feature. This
1465	  feature puts, at the beginning of functions, a canary value on
1466	  the stack just before the return address, and validates
1467	  the value just before actually returning.  Stack based buffer
1468	  overflows (that need to overwrite this return address) now also
1469	  overwrite the canary, which gets detected and the attack is then
1470	  neutralized via a kernel panic.
1471
1472	  This feature requires gcc version 4.2 or above, or a distribution
1473	  gcc with the feature backported. Older versions are automatically
1474	  detected and for those versions, this configuration option is
1475	  ignored. (and a warning is printed during bootup)
1476
1477source kernel/Kconfig.hz
1478
1479config KEXEC
1480	bool "kexec system call"
1481	---help---
1482	  kexec is a system call that implements the ability to shutdown your
1483	  current kernel, and to start another kernel.  It is like a reboot
1484	  but it is independent of the system firmware.   And like a reboot
1485	  you can start any kernel with it, not just Linux.
1486
1487	  The name comes from the similarity to the exec system call.
1488
1489	  It is an ongoing process to be certain the hardware in a machine
1490	  is properly shutdown, so do not be surprised if this code does not
1491	  initially work for you.  It may help to enable device hotplugging
1492	  support.  As of this writing the exact hardware interface is
1493	  strongly in flux, so no good recommendation can be made.
1494
1495config CRASH_DUMP
1496	bool "kernel crash dumps"
1497	depends on X86_64 || (X86_32 && HIGHMEM)
1498	---help---
1499	  Generate crash dump after being started by kexec.
1500	  This should be normally only set in special crash dump kernels
1501	  which are loaded in the main kernel with kexec-tools into
1502	  a specially reserved region and then later executed after
1503	  a crash by kdump/kexec. The crash dump kernel must be compiled
1504	  to a memory address not used by the main kernel or BIOS using
1505	  PHYSICAL_START, or it must be built as a relocatable image
1506	  (CONFIG_RELOCATABLE=y).
1507	  For more details see Documentation/kdump/kdump.txt
1508
1509config KEXEC_JUMP
1510	bool "kexec jump (EXPERIMENTAL)"
1511	depends on EXPERIMENTAL
1512	depends on KEXEC && HIBERNATION
1513	---help---
1514	  Jump between original kernel and kexeced kernel and invoke
1515	  code in physical address mode via KEXEC
1516
1517config PHYSICAL_START
1518	hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1519	default "0x1000000"
1520	---help---
1521	  This gives the physical address where the kernel is loaded.
1522
1523	  If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1524	  bzImage will decompress itself to above physical address and
1525	  run from there. Otherwise, bzImage will run from the address where
1526	  it has been loaded by the boot loader and will ignore above physical
1527	  address.
1528
1529	  In normal kdump cases one does not have to set/change this option
1530	  as now bzImage can be compiled as a completely relocatable image
1531	  (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1532	  address. This option is mainly useful for the folks who don't want
1533	  to use a bzImage for capturing the crash dump and want to use a
1534	  vmlinux instead. vmlinux is not relocatable hence a kernel needs
1535	  to be specifically compiled to run from a specific memory area
1536	  (normally a reserved region) and this option comes handy.
1537
1538	  So if you are using bzImage for capturing the crash dump,
1539	  leave the value here unchanged to 0x1000000 and set
1540	  CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
1541	  for capturing the crash dump change this value to start of
1542	  the reserved region.  In other words, it can be set based on
1543	  the "X" value as specified in the "crashkernel=YM@XM"
1544	  command line boot parameter passed to the panic-ed
1545	  kernel. Please take a look at Documentation/kdump/kdump.txt
1546	  for more details about crash dumps.
1547
1548	  Usage of bzImage for capturing the crash dump is recommended as
1549	  one does not have to build two kernels. Same kernel can be used
1550	  as production kernel and capture kernel. Above option should have
1551	  gone away after relocatable bzImage support is introduced. But it
1552	  is present because there are users out there who continue to use
1553	  vmlinux for dump capture. This option should go away down the
1554	  line.
1555
1556	  Don't change this unless you know what you are doing.
1557
1558config RELOCATABLE
1559	bool "Build a relocatable kernel"
1560	default y
1561	---help---
1562	  This builds a kernel image that retains relocation information
1563	  so it can be loaded someplace besides the default 1MB.
1564	  The relocations tend to make the kernel binary about 10% larger,
1565	  but are discarded at runtime.
1566
1567	  One use is for the kexec on panic case where the recovery kernel
1568	  must live at a different physical address than the primary
1569	  kernel.
1570
1571	  Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1572	  it has been loaded at and the compile time physical address
1573	  (CONFIG_PHYSICAL_START) is ignored.
1574
1575# Relocation on x86-32 needs some additional build support
1576config X86_NEED_RELOCS
1577	def_bool y
1578	depends on X86_32 && RELOCATABLE
1579
1580config PHYSICAL_ALIGN
1581	hex
1582	prompt "Alignment value to which kernel should be aligned" if X86_32
1583	default "0x1000000"
1584	range 0x2000 0x1000000
1585	---help---
1586	  This value puts the alignment restrictions on physical address
1587	  where kernel is loaded and run from. Kernel is compiled for an
1588	  address which meets above alignment restriction.
1589
1590	  If bootloader loads the kernel at a non-aligned address and
1591	  CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1592	  address aligned to above value and run from there.
1593
1594	  If bootloader loads the kernel at a non-aligned address and
1595	  CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1596	  load address and decompress itself to the address it has been
1597	  compiled for and run from there. The address for which kernel is
1598	  compiled already meets above alignment restrictions. Hence the
1599	  end result is that kernel runs from a physical address meeting
1600	  above alignment restrictions.
1601
1602	  Don't change this unless you know what you are doing.
1603
1604config HOTPLUG_CPU
1605	bool "Support for hot-pluggable CPUs"
1606	depends on SMP && HOTPLUG
1607	---help---
1608	  Say Y here to allow turning CPUs off and on. CPUs can be
1609	  controlled through /sys/devices/system/cpu.
1610	  ( Note: power management support will enable this option
1611	    automatically on SMP systems. )
1612	  Say N if you want to disable CPU hotplug.
1613
1614config COMPAT_VDSO
1615	def_bool y
1616	prompt "Compat VDSO support"
1617	depends on X86_32 || IA32_EMULATION
1618	---help---
1619	  Map the 32-bit VDSO to the predictable old-style address too.
1620	---help---
1621	  Say N here if you are running a sufficiently recent glibc
1622	  version (2.3.3 or later), to remove the high-mapped
1623	  VDSO mapping and to exclusively use the randomized VDSO.
1624
1625	  If unsure, say Y.
1626
1627config CMDLINE_BOOL
1628	bool "Built-in kernel command line"
1629	default n
1630	---help---
1631	  Allow for specifying boot arguments to the kernel at
1632	  build time.  On some systems (e.g. embedded ones), it is
1633	  necessary or convenient to provide some or all of the
1634	  kernel boot arguments with the kernel itself (that is,
1635	  to not rely on the boot loader to provide them.)
1636
1637	  To compile command line arguments into the kernel,
1638	  set this option to 'Y', then fill in the
1639	  the boot arguments in CONFIG_CMDLINE.
1640
1641	  Systems with fully functional boot loaders (i.e. non-embedded)
1642	  should leave this option set to 'N'.
1643
1644config CMDLINE
1645	string "Built-in kernel command string"
1646	depends on CMDLINE_BOOL
1647	default ""
1648	---help---
1649	  Enter arguments here that should be compiled into the kernel
1650	  image and used at boot time.  If the boot loader provides a
1651	  command line at boot time, it is appended to this string to
1652	  form the full kernel command line, when the system boots.
1653
1654	  However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1655	  change this behavior.
1656
1657	  In most cases, the command line (whether built-in or provided
1658	  by the boot loader) should specify the device for the root
1659	  file system.
1660
1661config CMDLINE_OVERRIDE
1662	bool "Built-in command line overrides boot loader arguments"
1663	default n
1664	depends on CMDLINE_BOOL
1665	---help---
1666	  Set this option to 'Y' to have the kernel ignore the boot loader
1667	  command line, and use ONLY the built-in command line.
1668
1669	  This is used to work around broken boot loaders.  This should
1670	  be set to 'N' under normal conditions.
1671
1672endmenu
1673
1674config ARCH_ENABLE_MEMORY_HOTPLUG
1675	def_bool y
1676	depends on X86_64 || (X86_32 && HIGHMEM)
1677
1678config ARCH_ENABLE_MEMORY_HOTREMOVE
1679	def_bool y
1680	depends on MEMORY_HOTPLUG
1681
1682config HAVE_ARCH_EARLY_PFN_TO_NID
1683	def_bool X86_64
1684	depends on NUMA
1685
1686menu "Power management and ACPI options"
1687
1688config ARCH_HIBERNATION_HEADER
1689	def_bool y
1690	depends on X86_64 && HIBERNATION
1691
1692source "kernel/power/Kconfig"
1693
1694source "drivers/acpi/Kconfig"
1695
1696config X86_APM_BOOT
1697	bool
1698	default y
1699	depends on APM || APM_MODULE
1700
1701menuconfig APM
1702	tristate "APM (Advanced Power Management) BIOS support"
1703	depends on X86_32 && PM_SLEEP
1704	---help---
1705	  APM is a BIOS specification for saving power using several different
1706	  techniques. This is mostly useful for battery powered laptops with
1707	  APM compliant BIOSes. If you say Y here, the system time will be
1708	  reset after a RESUME operation, the /proc/apm device will provide
1709	  battery status information, and user-space programs will receive
1710	  notification of APM "events" (e.g. battery status change).
1711
1712	  If you select "Y" here, you can disable actual use of the APM
1713	  BIOS by passing the "apm=off" option to the kernel at boot time.
1714
1715	  Note that the APM support is almost completely disabled for
1716	  machines with more than one CPU.
1717
1718	  In order to use APM, you will need supporting software. For location
1719	  and more information, read <file:Documentation/power/pm.txt> and the
1720	  Battery Powered Linux mini-HOWTO, available from
1721	  <http://www.tldp.org/docs.html#howto>.
1722
1723	  This driver does not spin down disk drives (see the hdparm(8)
1724	  manpage ("man 8 hdparm") for that), and it doesn't turn off
1725	  VESA-compliant "green" monitors.
1726
1727	  This driver does not support the TI 4000M TravelMate and the ACER
1728	  486/DX4/75 because they don't have compliant BIOSes. Many "green"
1729	  desktop machines also don't have compliant BIOSes, and this driver
1730	  may cause those machines to panic during the boot phase.
1731
1732	  Generally, if you don't have a battery in your machine, there isn't
1733	  much point in using this driver and you should say N. If you get
1734	  random kernel OOPSes or reboots that don't seem to be related to
1735	  anything, try disabling/enabling this option (or disabling/enabling
1736	  APM in your BIOS).
1737
1738	  Some other things you should try when experiencing seemingly random,
1739	  "weird" problems:
1740
1741	  1) make sure that you have enough swap space and that it is
1742	  enabled.
1743	  2) pass the "no-hlt" option to the kernel
1744	  3) switch on floating point emulation in the kernel and pass
1745	  the "no387" option to the kernel
1746	  4) pass the "floppy=nodma" option to the kernel
1747	  5) pass the "mem=4M" option to the kernel (thereby disabling
1748	  all but the first 4 MB of RAM)
1749	  6) make sure that the CPU is not over clocked.
1750	  7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1751	  8) disable the cache from your BIOS settings
1752	  9) install a fan for the video card or exchange video RAM
1753	  10) install a better fan for the CPU
1754	  11) exchange RAM chips
1755	  12) exchange the motherboard.
1756
1757	  To compile this driver as a module, choose M here: the
1758	  module will be called apm.
1759
1760if APM
1761
1762config APM_IGNORE_USER_SUSPEND
1763	bool "Ignore USER SUSPEND"
1764	---help---
1765	  This option will ignore USER SUSPEND requests. On machines with a
1766	  compliant APM BIOS, you want to say N. However, on the NEC Versa M
1767	  series notebooks, it is necessary to say Y because of a BIOS bug.
1768
1769config APM_DO_ENABLE
1770	bool "Enable PM at boot time"
1771	---help---
1772	  Enable APM features at boot time. From page 36 of the APM BIOS
1773	  specification: "When disabled, the APM BIOS does not automatically
1774	  power manage devices, enter the Standby State, enter the Suspend
1775	  State, or take power saving steps in response to CPU Idle calls."
1776	  This driver will make CPU Idle calls when Linux is idle (unless this
1777	  feature is turned off -- see "Do CPU IDLE calls", below). This
1778	  should always save battery power, but more complicated APM features
1779	  will be dependent on your BIOS implementation. You may need to turn
1780	  this option off if your computer hangs at boot time when using APM
1781	  support, or if it beeps continuously instead of suspending. Turn
1782	  this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1783	  T400CDT. This is off by default since most machines do fine without
1784	  this feature.
1785
1786config APM_CPU_IDLE
1787	bool "Make CPU Idle calls when idle"
1788	---help---
1789	  Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1790	  On some machines, this can activate improved power savings, such as
1791	  a slowed CPU clock rate, when the machine is idle. These idle calls
1792	  are made after the idle loop has run for some length of time (e.g.,
1793	  333 mS). On some machines, this will cause a hang at boot time or
1794	  whenever the CPU becomes idle. (On machines with more than one CPU,
1795	  this option does nothing.)
1796
1797config APM_DISPLAY_BLANK
1798	bool "Enable console blanking using APM"
1799	---help---
1800	  Enable console blanking using the APM. Some laptops can use this to
1801	  turn off the LCD backlight when the screen blanker of the Linux
1802	  virtual console blanks the screen. Note that this is only used by
1803	  the virtual console screen blanker, and won't turn off the backlight
1804	  when using the X Window system. This also doesn't have anything to
1805	  do with your VESA-compliant power-saving monitor. Further, this
1806	  option doesn't work for all laptops -- it might not turn off your
1807	  backlight at all, or it might print a lot of errors to the console,
1808	  especially if you are using gpm.
1809
1810config APM_ALLOW_INTS
1811	bool "Allow interrupts during APM BIOS calls"
1812	---help---
1813	  Normally we disable external interrupts while we are making calls to
1814	  the APM BIOS as a measure to lessen the effects of a badly behaving
1815	  BIOS implementation.  The BIOS should reenable interrupts if it
1816	  needs to.  Unfortunately, some BIOSes do not -- especially those in
1817	  many of the newer IBM Thinkpads.  If you experience hangs when you
1818	  suspend, try setting this to Y.  Otherwise, say N.
1819
1820endif # APM
1821
1822source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1823
1824source "drivers/cpuidle/Kconfig"
1825
1826source "drivers/idle/Kconfig"
1827
1828endmenu
1829
1830
1831menu "Bus options (PCI etc.)"
1832
1833config PCI
1834	bool "PCI support"
1835	default y
1836	select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1837	---help---
1838	  Find out whether you have a PCI motherboard. PCI is the name of a
1839	  bus system, i.e. the way the CPU talks to the other stuff inside
1840	  your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1841	  VESA. If you have PCI, say Y, otherwise N.
1842
1843choice
1844	prompt "PCI access mode"
1845	depends on X86_32 && PCI
1846	default PCI_GOANY
1847	---help---
1848	  On PCI systems, the BIOS can be used to detect the PCI devices and
1849	  determine their configuration. However, some old PCI motherboards
1850	  have BIOS bugs and may crash if this is done. Also, some embedded
1851	  PCI-based systems don't have any BIOS at all. Linux can also try to
1852	  detect the PCI hardware directly without using the BIOS.
1853
1854	  With this option, you can specify how Linux should detect the
1855	  PCI devices. If you choose "BIOS", the BIOS will be used,
1856	  if you choose "Direct", the BIOS won't be used, and if you
1857	  choose "MMConfig", then PCI Express MMCONFIG will be used.
1858	  If you choose "Any", the kernel will try MMCONFIG, then the
1859	  direct access method and falls back to the BIOS if that doesn't
1860	  work. If unsure, go with the default, which is "Any".
1861
1862config PCI_GOBIOS
1863	bool "BIOS"
1864
1865config PCI_GOMMCONFIG
1866	bool "MMConfig"
1867
1868config PCI_GODIRECT
1869	bool "Direct"
1870
1871config PCI_GOOLPC
1872	bool "OLPC"
1873	depends on OLPC
1874
1875config PCI_GOANY
1876	bool "Any"
1877
1878endchoice
1879
1880config PCI_BIOS
1881	def_bool y
1882	depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1883
1884# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1885config PCI_DIRECT
1886	def_bool y
1887	depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1888
1889config PCI_MMCONFIG
1890	def_bool y
1891	depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1892
1893config PCI_OLPC
1894	def_bool y
1895	depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1896
1897config PCI_DOMAINS
1898	def_bool y
1899	depends on PCI
1900
1901config PCI_MMCONFIG
1902	bool "Support mmconfig PCI config space access"
1903	depends on X86_64 && PCI && ACPI
1904
1905config DMAR
1906	bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1907	depends on PCI_MSI && ACPI && EXPERIMENTAL
1908	help
1909	  DMA remapping (DMAR) devices support enables independent address
1910	  translations for Direct Memory Access (DMA) from devices.
1911	  These DMA remapping devices are reported via ACPI tables
1912	  and include PCI device scope covered by these DMA
1913	  remapping devices.
1914
1915config DMAR_DEFAULT_ON
1916	def_bool y
1917	prompt "Enable DMA Remapping Devices by default"
1918	depends on DMAR
1919	help
1920	  Selecting this option will enable a DMAR device at boot time if
1921	  one is found. If this option is not selected, DMAR support can
1922	  be enabled by passing intel_iommu=on to the kernel. It is
1923	  recommended you say N here while the DMAR code remains
1924	  experimental.
1925
1926config DMAR_BROKEN_GFX_WA
1927	def_bool n
1928	prompt "Workaround broken graphics drivers (going away soon)"
1929	depends on DMAR
1930	---help---
1931	  Current Graphics drivers tend to use physical address
1932	  for DMA and avoid using DMA APIs. Setting this config
1933	  option permits the IOMMU driver to set a unity map for
1934	  all the OS-visible memory. Hence the driver can continue
1935	  to use physical addresses for DMA, at least until this
1936	  option is removed in the 2.6.32 kernel.
1937
1938config DMAR_FLOPPY_WA
1939	def_bool y
1940	depends on DMAR
1941	---help---
1942	  Floppy disk drivers are known to bypass DMA API calls
1943	  thereby failing to work when IOMMU is enabled. This
1944	  workaround will setup a 1:1 mapping for the first
1945	  16MiB to make floppy (an ISA device) work.
1946
1947config INTR_REMAP
1948	bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1949	depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
1950	---help---
1951	  Supports Interrupt remapping for IO-APIC and MSI devices.
1952	  To use x2apic mode in the CPU's which support x2APIC enhancements or
1953	  to support platforms with CPU's having > 8 bit APIC ID, say Y.
1954
1955source "drivers/pci/pcie/Kconfig"
1956
1957source "drivers/pci/Kconfig"
1958
1959# x86_64 have no ISA slots, but do have ISA-style DMA.
1960config ISA_DMA_API
1961	def_bool y
1962
1963if X86_32
1964
1965config ISA
1966	bool "ISA support"
1967	---help---
1968	  Find out whether you have ISA slots on your motherboard.  ISA is the
1969	  name of a bus system, i.e. the way the CPU talks to the other stuff
1970	  inside your box.  Other bus systems are PCI, EISA, MicroChannel
1971	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
1972	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
1973
1974config EISA
1975	bool "EISA support"
1976	depends on ISA
1977	---help---
1978	  The Extended Industry Standard Architecture (EISA) bus was
1979	  developed as an open alternative to the IBM MicroChannel bus.
1980
1981	  The EISA bus provided some of the features of the IBM MicroChannel
1982	  bus while maintaining backward compatibility with cards made for
1983	  the older ISA bus.  The EISA bus saw limited use between 1988 and
1984	  1995 when it was made obsolete by the PCI bus.
1985
1986	  Say Y here if you are building a kernel for an EISA-based machine.
1987
1988	  Otherwise, say N.
1989
1990source "drivers/eisa/Kconfig"
1991
1992config MCA
1993	bool "MCA support"
1994	---help---
1995	  MicroChannel Architecture is found in some IBM PS/2 machines and
1996	  laptops.  It is a bus system similar to PCI or ISA. See
1997	  <file:Documentation/mca.txt> (and especially the web page given
1998	  there) before attempting to build an MCA bus kernel.
1999
2000source "drivers/mca/Kconfig"
2001
2002config SCx200
2003	tristate "NatSemi SCx200 support"
2004	---help---
2005	  This provides basic support for National Semiconductor's
2006	  (now AMD's) Geode processors.  The driver probes for the
2007	  PCI-IDs of several on-chip devices, so its a good dependency
2008	  for other scx200_* drivers.
2009
2010	  If compiled as a module, the driver is named scx200.
2011
2012config SCx200HR_TIMER
2013	tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2014	depends on SCx200 && GENERIC_TIME
2015	default y
2016	---help---
2017	  This driver provides a clocksource built upon the on-chip
2018	  27MHz high-resolution timer.  Its also a workaround for
2019	  NSC Geode SC-1100's buggy TSC, which loses time when the
2020	  processor goes idle (as is done by the scheduler).  The
2021	  other workaround is idle=poll boot option.
2022
2023config GEODE_MFGPT_TIMER
2024	def_bool y
2025	prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
2026	depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
2027	---help---
2028	  This driver provides a clock event source based on the MFGPT
2029	  timer(s) in the CS5535 and CS5536 companion chip for the geode.
2030	  MFGPTs have a better resolution and max interval than the
2031	  generic PIT, and are suitable for use as high-res timers.
2032
2033config OLPC
2034	bool "One Laptop Per Child support"
2035	default n
2036	---help---
2037	  Add support for detecting the unique features of the OLPC
2038	  XO hardware.
2039
2040endif # X86_32
2041
2042config K8_NB
2043	def_bool y
2044	depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
2045
2046source "drivers/pcmcia/Kconfig"
2047
2048source "drivers/pci/hotplug/Kconfig"
2049
2050endmenu
2051
2052
2053menu "Executable file formats / Emulations"
2054
2055source "fs/Kconfig.binfmt"
2056
2057config IA32_EMULATION
2058	bool "IA32 Emulation"
2059	depends on X86_64
2060	select COMPAT_BINFMT_ELF
2061	---help---
2062	  Include code to run 32-bit programs under a 64-bit kernel. You should
2063	  likely turn this on, unless you're 100% sure that you don't have any
2064	  32-bit programs left.
2065
2066config IA32_AOUT
2067	tristate "IA32 a.out support"
2068	depends on IA32_EMULATION
2069	---help---
2070	  Support old a.out binaries in the 32bit emulation.
2071
2072config COMPAT
2073	def_bool y
2074	depends on IA32_EMULATION
2075
2076config COMPAT_FOR_U64_ALIGNMENT
2077	def_bool COMPAT
2078	depends on X86_64
2079
2080config SYSVIPC_COMPAT
2081	def_bool y
2082	depends on COMPAT && SYSVIPC
2083
2084endmenu
2085
2086
2087config HAVE_ATOMIC_IOMAP
2088	def_bool y
2089	depends on X86_32
2090
2091source "net/Kconfig"
2092
2093source "drivers/Kconfig"
2094
2095source "drivers/firmware/Kconfig"
2096
2097source "fs/Kconfig"
2098
2099source "arch/x86/Kconfig.debug"
2100
2101source "security/Kconfig"
2102
2103source "crypto/Kconfig"
2104
2105source "arch/x86/kvm/Kconfig"
2106
2107source "lib/Kconfig"
2108