xref: /openbmc/linux/arch/x86/Kconfig (revision 62e7ca52)
1# Select 32 or 64 bit
2config 64BIT
3	bool "64-bit kernel" if ARCH = "x86"
4	default ARCH != "i386"
5	---help---
6	  Say yes to build a 64-bit kernel - formerly known as x86_64
7	  Say no to build a 32-bit kernel - formerly known as i386
8
9config X86_32
10	def_bool y
11	depends on !64BIT
12	select CLKSRC_I8253
13	select HAVE_UID16
14
15config X86_64
16	def_bool y
17	depends on 64BIT
18	select X86_DEV_DMA_OPS
19	select ARCH_USE_CMPXCHG_LOCKREF
20
21### Arch settings
22config X86
23	def_bool y
24	select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
25	select ARCH_MIGHT_HAVE_PC_PARPORT
26	select ARCH_MIGHT_HAVE_PC_SERIO
27	select HAVE_AOUT if X86_32
28	select HAVE_UNSTABLE_SCHED_CLOCK
29	select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
30	select ARCH_SUPPORTS_INT128 if X86_64
31	select ARCH_WANTS_PROT_NUMA_PROT_NONE
32	select HAVE_IDE
33	select HAVE_OPROFILE
34	select HAVE_PCSPKR_PLATFORM
35	select HAVE_PERF_EVENTS
36	select HAVE_IOREMAP_PROT
37	select HAVE_KPROBES
38	select HAVE_MEMBLOCK
39	select HAVE_MEMBLOCK_NODE_MAP
40	select ARCH_DISCARD_MEMBLOCK
41	select ARCH_WANT_OPTIONAL_GPIOLIB
42	select ARCH_WANT_FRAME_POINTERS
43	select HAVE_DMA_ATTRS
44	select HAVE_DMA_CONTIGUOUS
45	select HAVE_KRETPROBES
46	select GENERIC_EARLY_IOREMAP
47	select HAVE_OPTPROBES
48	select HAVE_KPROBES_ON_FTRACE
49	select HAVE_FTRACE_MCOUNT_RECORD
50	select HAVE_FENTRY if X86_64
51	select HAVE_C_RECORDMCOUNT
52	select HAVE_DYNAMIC_FTRACE
53	select HAVE_DYNAMIC_FTRACE_WITH_REGS
54	select HAVE_FUNCTION_TRACER
55	select HAVE_FUNCTION_GRAPH_TRACER
56	select HAVE_FUNCTION_GRAPH_FP_TEST
57	select HAVE_SYSCALL_TRACEPOINTS
58	select SYSCTL_EXCEPTION_TRACE
59	select HAVE_KVM
60	select HAVE_ARCH_KGDB
61	select HAVE_ARCH_TRACEHOOK
62	select HAVE_GENERIC_DMA_COHERENT if X86_32
63	select HAVE_EFFICIENT_UNALIGNED_ACCESS
64	select USER_STACKTRACE_SUPPORT
65	select HAVE_REGS_AND_STACK_ACCESS_API
66	select HAVE_DMA_API_DEBUG
67	select HAVE_KERNEL_GZIP
68	select HAVE_KERNEL_BZIP2
69	select HAVE_KERNEL_LZMA
70	select HAVE_KERNEL_XZ
71	select HAVE_KERNEL_LZO
72	select HAVE_KERNEL_LZ4
73	select HAVE_HW_BREAKPOINT
74	select HAVE_MIXED_BREAKPOINTS_REGS
75	select PERF_EVENTS
76	select HAVE_PERF_EVENTS_NMI
77	select HAVE_PERF_REGS
78	select HAVE_PERF_USER_STACK_DUMP
79	select HAVE_DEBUG_KMEMLEAK
80	select ANON_INODES
81	select HAVE_ALIGNED_STRUCT_PAGE if SLUB
82	select HAVE_CMPXCHG_LOCAL
83	select HAVE_CMPXCHG_DOUBLE
84	select HAVE_ARCH_KMEMCHECK
85	select HAVE_USER_RETURN_NOTIFIER
86	select ARCH_BINFMT_ELF_RANDOMIZE_PIE
87	select HAVE_ARCH_JUMP_LABEL
88	select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
89	select SPARSE_IRQ
90	select GENERIC_FIND_FIRST_BIT
91	select GENERIC_IRQ_PROBE
92	select GENERIC_PENDING_IRQ if SMP
93	select GENERIC_IRQ_SHOW
94	select GENERIC_CLOCKEVENTS_MIN_ADJUST
95	select IRQ_FORCED_THREADING
96	select HAVE_BPF_JIT if X86_64
97	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
98	select CLKEVT_I8253
99	select ARCH_HAVE_NMI_SAFE_CMPXCHG
100	select GENERIC_IOMAP
101	select DCACHE_WORD_ACCESS
102	select GENERIC_SMP_IDLE_THREAD
103	select ARCH_WANT_IPC_PARSE_VERSION if X86_32
104	select HAVE_ARCH_SECCOMP_FILTER
105	select BUILDTIME_EXTABLE_SORT
106	select GENERIC_CMOS_UPDATE
107	select HAVE_ARCH_SOFT_DIRTY if X86_64
108	select CLOCKSOURCE_WATCHDOG
109	select GENERIC_CLOCKEVENTS
110	select ARCH_CLOCKSOURCE_DATA
111	select CLOCKSOURCE_VALIDATE_LAST_CYCLE
112	select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
113	select GENERIC_TIME_VSYSCALL
114	select GENERIC_STRNCPY_FROM_USER
115	select GENERIC_STRNLEN_USER
116	select HAVE_CONTEXT_TRACKING if X86_64
117	select HAVE_IRQ_TIME_ACCOUNTING
118	select VIRT_TO_BUS
119	select MODULES_USE_ELF_REL if X86_32
120	select MODULES_USE_ELF_RELA if X86_64
121	select CLONE_BACKWARDS if X86_32
122	select ARCH_USE_BUILTIN_BSWAP
123	select ARCH_USE_QUEUE_RWLOCK
124	select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
125	select OLD_SIGACTION if X86_32
126	select COMPAT_OLD_SIGACTION if IA32_EMULATION
127	select RTC_LIB
128	select HAVE_DEBUG_STACKOVERFLOW
129	select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
130	select HAVE_CC_STACKPROTECTOR
131	select GENERIC_CPU_AUTOPROBE
132	select HAVE_ARCH_AUDITSYSCALL
133	select ARCH_SUPPORTS_ATOMIC_RMW
134	select HAVE_ACPI_APEI if ACPI
135	select HAVE_ACPI_APEI_NMI if ACPI
136
137config INSTRUCTION_DECODER
138	def_bool y
139	depends on KPROBES || PERF_EVENTS || UPROBES
140
141config OUTPUT_FORMAT
142	string
143	default "elf32-i386" if X86_32
144	default "elf64-x86-64" if X86_64
145
146config ARCH_DEFCONFIG
147	string
148	default "arch/x86/configs/i386_defconfig" if X86_32
149	default "arch/x86/configs/x86_64_defconfig" if X86_64
150
151config LOCKDEP_SUPPORT
152	def_bool y
153
154config STACKTRACE_SUPPORT
155	def_bool y
156
157config HAVE_LATENCYTOP_SUPPORT
158	def_bool y
159
160config MMU
161	def_bool y
162
163config SBUS
164	bool
165
166config NEED_DMA_MAP_STATE
167	def_bool y
168	depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG
169
170config NEED_SG_DMA_LENGTH
171	def_bool y
172
173config GENERIC_ISA_DMA
174	def_bool y
175	depends on ISA_DMA_API
176
177config GENERIC_BUG
178	def_bool y
179	depends on BUG
180	select GENERIC_BUG_RELATIVE_POINTERS if X86_64
181
182config GENERIC_BUG_RELATIVE_POINTERS
183	bool
184
185config GENERIC_HWEIGHT
186	def_bool y
187
188config ARCH_MAY_HAVE_PC_FDC
189	def_bool y
190	depends on ISA_DMA_API
191
192config RWSEM_XCHGADD_ALGORITHM
193	def_bool y
194
195config GENERIC_CALIBRATE_DELAY
196	def_bool y
197
198config ARCH_HAS_CPU_RELAX
199	def_bool y
200
201config ARCH_HAS_CACHE_LINE_SIZE
202	def_bool y
203
204config HAVE_SETUP_PER_CPU_AREA
205	def_bool y
206
207config NEED_PER_CPU_EMBED_FIRST_CHUNK
208	def_bool y
209
210config NEED_PER_CPU_PAGE_FIRST_CHUNK
211	def_bool y
212
213config ARCH_HIBERNATION_POSSIBLE
214	def_bool y
215
216config ARCH_SUSPEND_POSSIBLE
217	def_bool y
218
219config ARCH_WANT_HUGE_PMD_SHARE
220	def_bool y
221
222config ARCH_WANT_GENERAL_HUGETLB
223	def_bool y
224
225config ZONE_DMA32
226	bool
227	default X86_64
228
229config AUDIT_ARCH
230	bool
231	default X86_64
232
233config ARCH_SUPPORTS_OPTIMIZED_INLINING
234	def_bool y
235
236config ARCH_SUPPORTS_DEBUG_PAGEALLOC
237	def_bool y
238
239config HAVE_INTEL_TXT
240	def_bool y
241	depends on INTEL_IOMMU && ACPI
242
243config X86_32_SMP
244	def_bool y
245	depends on X86_32 && SMP
246
247config X86_64_SMP
248	def_bool y
249	depends on X86_64 && SMP
250
251config X86_HT
252	def_bool y
253	depends on SMP
254
255config X86_32_LAZY_GS
256	def_bool y
257	depends on X86_32 && !CC_STACKPROTECTOR
258
259config ARCH_HWEIGHT_CFLAGS
260	string
261	default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
262	default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64
263
264config ARCH_SUPPORTS_UPROBES
265	def_bool y
266
267config FIX_EARLYCON_MEM
268	def_bool y
269
270source "init/Kconfig"
271source "kernel/Kconfig.freezer"
272
273menu "Processor type and features"
274
275config ZONE_DMA
276	bool "DMA memory allocation support" if EXPERT
277	default y
278	help
279	  DMA memory allocation support allows devices with less than 32-bit
280	  addressing to allocate within the first 16MB of address space.
281	  Disable if no such devices will be used.
282
283	  If unsure, say Y.
284
285config SMP
286	bool "Symmetric multi-processing support"
287	---help---
288	  This enables support for systems with more than one CPU. If you have
289	  a system with only one CPU, say N. If you have a system with more
290	  than one CPU, say Y.
291
292	  If you say N here, the kernel will run on uni- and multiprocessor
293	  machines, but will use only one CPU of a multiprocessor machine. If
294	  you say Y here, the kernel will run on many, but not all,
295	  uniprocessor machines. On a uniprocessor machine, the kernel
296	  will run faster if you say N here.
297
298	  Note that if you say Y here and choose architecture "586" or
299	  "Pentium" under "Processor family", the kernel will not work on 486
300	  architectures. Similarly, multiprocessor kernels for the "PPro"
301	  architecture may not work on all Pentium based boards.
302
303	  People using multiprocessor machines who say Y here should also say
304	  Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
305	  Management" code will be disabled if you say Y here.
306
307	  See also <file:Documentation/x86/i386/IO-APIC.txt>,
308	  <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
309	  <http://www.tldp.org/docs.html#howto>.
310
311	  If you don't know what to do here, say N.
312
313config X86_X2APIC
314	bool "Support x2apic"
315	depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
316	---help---
317	  This enables x2apic support on CPUs that have this feature.
318
319	  This allows 32-bit apic IDs (so it can support very large systems),
320	  and accesses the local apic via MSRs not via mmio.
321
322	  If you don't know what to do here, say N.
323
324config X86_MPPARSE
325	bool "Enable MPS table" if ACPI || SFI
326	default y
327	depends on X86_LOCAL_APIC
328	---help---
329	  For old smp systems that do not have proper acpi support. Newer systems
330	  (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
331
332config X86_BIGSMP
333	bool "Support for big SMP systems with more than 8 CPUs"
334	depends on X86_32 && SMP
335	---help---
336	  This option is needed for the systems that have more than 8 CPUs
337
338config GOLDFISH
339       def_bool y
340       depends on X86_GOLDFISH
341
342if X86_32
343config X86_EXTENDED_PLATFORM
344	bool "Support for extended (non-PC) x86 platforms"
345	default y
346	---help---
347	  If you disable this option then the kernel will only support
348	  standard PC platforms. (which covers the vast majority of
349	  systems out there.)
350
351	  If you enable this option then you'll be able to select support
352	  for the following (non-PC) 32 bit x86 platforms:
353		Goldfish (Android emulator)
354		AMD Elan
355		RDC R-321x SoC
356		SGI 320/540 (Visual Workstation)
357		STA2X11-based (e.g. Northville)
358		Moorestown MID devices
359
360	  If you have one of these systems, or if you want to build a
361	  generic distribution kernel, say Y here - otherwise say N.
362endif
363
364if X86_64
365config X86_EXTENDED_PLATFORM
366	bool "Support for extended (non-PC) x86 platforms"
367	default y
368	---help---
369	  If you disable this option then the kernel will only support
370	  standard PC platforms. (which covers the vast majority of
371	  systems out there.)
372
373	  If you enable this option then you'll be able to select support
374	  for the following (non-PC) 64 bit x86 platforms:
375		Numascale NumaChip
376		ScaleMP vSMP
377		SGI Ultraviolet
378
379	  If you have one of these systems, or if you want to build a
380	  generic distribution kernel, say Y here - otherwise say N.
381endif
382# This is an alphabetically sorted list of 64 bit extended platforms
383# Please maintain the alphabetic order if and when there are additions
384config X86_NUMACHIP
385	bool "Numascale NumaChip"
386	depends on X86_64
387	depends on X86_EXTENDED_PLATFORM
388	depends on NUMA
389	depends on SMP
390	depends on X86_X2APIC
391	depends on PCI_MMCONFIG
392	---help---
393	  Adds support for Numascale NumaChip large-SMP systems. Needed to
394	  enable more than ~168 cores.
395	  If you don't have one of these, you should say N here.
396
397config X86_VSMP
398	bool "ScaleMP vSMP"
399	select HYPERVISOR_GUEST
400	select PARAVIRT
401	depends on X86_64 && PCI
402	depends on X86_EXTENDED_PLATFORM
403	depends on SMP
404	---help---
405	  Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
406	  supposed to run on these EM64T-based machines.  Only choose this option
407	  if you have one of these machines.
408
409config X86_UV
410	bool "SGI Ultraviolet"
411	depends on X86_64
412	depends on X86_EXTENDED_PLATFORM
413	depends on NUMA
414	depends on X86_X2APIC
415	---help---
416	  This option is needed in order to support SGI Ultraviolet systems.
417	  If you don't have one of these, you should say N here.
418
419# Following is an alphabetically sorted list of 32 bit extended platforms
420# Please maintain the alphabetic order if and when there are additions
421
422config X86_GOLDFISH
423       bool "Goldfish (Virtual Platform)"
424       depends on X86_EXTENDED_PLATFORM
425       ---help---
426	 Enable support for the Goldfish virtual platform used primarily
427	 for Android development. Unless you are building for the Android
428	 Goldfish emulator say N here.
429
430config X86_INTEL_CE
431	bool "CE4100 TV platform"
432	depends on PCI
433	depends on PCI_GODIRECT
434	depends on X86_32
435	depends on X86_EXTENDED_PLATFORM
436	select X86_REBOOTFIXUPS
437	select OF
438	select OF_EARLY_FLATTREE
439	select IRQ_DOMAIN
440	---help---
441	  Select for the Intel CE media processor (CE4100) SOC.
442	  This option compiles in support for the CE4100 SOC for settop
443	  boxes and media devices.
444
445config X86_INTEL_MID
446	bool "Intel MID platform support"
447	depends on X86_32
448	depends on X86_EXTENDED_PLATFORM
449	depends on X86_PLATFORM_DEVICES
450	depends on PCI
451	depends on PCI_GOANY
452	depends on X86_IO_APIC
453	select SFI
454	select I2C
455	select DW_APB_TIMER
456	select APB_TIMER
457	select INTEL_SCU_IPC
458	select MFD_INTEL_MSIC
459	---help---
460	  Select to build a kernel capable of supporting Intel MID (Mobile
461	  Internet Device) platform systems which do not have the PCI legacy
462	  interfaces. If you are building for a PC class system say N here.
463
464	  Intel MID platforms are based on an Intel processor and chipset which
465	  consume less power than most of the x86 derivatives.
466
467config X86_INTEL_LPSS
468	bool "Intel Low Power Subsystem Support"
469	depends on ACPI
470	select COMMON_CLK
471	select PINCTRL
472	---help---
473	  Select to build support for Intel Low Power Subsystem such as
474	  found on Intel Lynxpoint PCH. Selecting this option enables
475	  things like clock tree (common clock framework) and pincontrol
476	  which are needed by the LPSS peripheral drivers.
477
478config X86_RDC321X
479	bool "RDC R-321x SoC"
480	depends on X86_32
481	depends on X86_EXTENDED_PLATFORM
482	select M486
483	select X86_REBOOTFIXUPS
484	---help---
485	  This option is needed for RDC R-321x system-on-chip, also known
486	  as R-8610-(G).
487	  If you don't have one of these chips, you should say N here.
488
489config X86_32_NON_STANDARD
490	bool "Support non-standard 32-bit SMP architectures"
491	depends on X86_32 && SMP
492	depends on X86_EXTENDED_PLATFORM
493	---help---
494	  This option compiles in the bigsmp and STA2X11 default
495	  subarchitectures.  It is intended for a generic binary
496	  kernel. If you select them all, kernel will probe it one by
497	  one and will fallback to default.
498
499# Alphabetically sorted list of Non standard 32 bit platforms
500
501config X86_SUPPORTS_MEMORY_FAILURE
502	def_bool y
503	# MCE code calls memory_failure():
504	depends on X86_MCE
505	# On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
506	# On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
507	depends on X86_64 || !SPARSEMEM
508	select ARCH_SUPPORTS_MEMORY_FAILURE
509
510config STA2X11
511	bool "STA2X11 Companion Chip Support"
512	depends on X86_32_NON_STANDARD && PCI
513	select X86_DEV_DMA_OPS
514	select X86_DMA_REMAP
515	select SWIOTLB
516	select MFD_STA2X11
517	select ARCH_REQUIRE_GPIOLIB
518	default n
519	---help---
520	  This adds support for boards based on the STA2X11 IO-Hub,
521	  a.k.a. "ConneXt". The chip is used in place of the standard
522	  PC chipset, so all "standard" peripherals are missing. If this
523	  option is selected the kernel will still be able to boot on
524	  standard PC machines.
525
526config X86_32_IRIS
527	tristate "Eurobraille/Iris poweroff module"
528	depends on X86_32
529	---help---
530	  The Iris machines from EuroBraille do not have APM or ACPI support
531	  to shut themselves down properly.  A special I/O sequence is
532	  needed to do so, which is what this module does at
533	  kernel shutdown.
534
535	  This is only for Iris machines from EuroBraille.
536
537	  If unused, say N.
538
539config SCHED_OMIT_FRAME_POINTER
540	def_bool y
541	prompt "Single-depth WCHAN output"
542	depends on X86
543	---help---
544	  Calculate simpler /proc/<PID>/wchan values. If this option
545	  is disabled then wchan values will recurse back to the
546	  caller function. This provides more accurate wchan values,
547	  at the expense of slightly more scheduling overhead.
548
549	  If in doubt, say "Y".
550
551menuconfig HYPERVISOR_GUEST
552	bool "Linux guest support"
553	---help---
554	  Say Y here to enable options for running Linux under various hyper-
555	  visors. This option enables basic hypervisor detection and platform
556	  setup.
557
558	  If you say N, all options in this submenu will be skipped and
559	  disabled, and Linux guest support won't be built in.
560
561if HYPERVISOR_GUEST
562
563config PARAVIRT
564	bool "Enable paravirtualization code"
565	---help---
566	  This changes the kernel so it can modify itself when it is run
567	  under a hypervisor, potentially improving performance significantly
568	  over full virtualization.  However, when run without a hypervisor
569	  the kernel is theoretically slower and slightly larger.
570
571config PARAVIRT_DEBUG
572	bool "paravirt-ops debugging"
573	depends on PARAVIRT && DEBUG_KERNEL
574	---help---
575	  Enable to debug paravirt_ops internals.  Specifically, BUG if
576	  a paravirt_op is missing when it is called.
577
578config PARAVIRT_SPINLOCKS
579	bool "Paravirtualization layer for spinlocks"
580	depends on PARAVIRT && SMP
581	select UNINLINE_SPIN_UNLOCK
582	---help---
583	  Paravirtualized spinlocks allow a pvops backend to replace the
584	  spinlock implementation with something virtualization-friendly
585	  (for example, block the virtual CPU rather than spinning).
586
587	  It has a minimal impact on native kernels and gives a nice performance
588	  benefit on paravirtualized KVM / Xen kernels.
589
590	  If you are unsure how to answer this question, answer Y.
591
592source "arch/x86/xen/Kconfig"
593
594config KVM_GUEST
595	bool "KVM Guest support (including kvmclock)"
596	depends on PARAVIRT
597	select PARAVIRT_CLOCK
598	default y
599	---help---
600	  This option enables various optimizations for running under the KVM
601	  hypervisor. It includes a paravirtualized clock, so that instead
602	  of relying on a PIT (or probably other) emulation by the
603	  underlying device model, the host provides the guest with
604	  timing infrastructure such as time of day, and system time
605
606config KVM_DEBUG_FS
607	bool "Enable debug information for KVM Guests in debugfs"
608	depends on KVM_GUEST && DEBUG_FS
609	default n
610	---help---
611	  This option enables collection of various statistics for KVM guest.
612	  Statistics are displayed in debugfs filesystem. Enabling this option
613	  may incur significant overhead.
614
615source "arch/x86/lguest/Kconfig"
616
617config PARAVIRT_TIME_ACCOUNTING
618	bool "Paravirtual steal time accounting"
619	depends on PARAVIRT
620	default n
621	---help---
622	  Select this option to enable fine granularity task steal time
623	  accounting. Time spent executing other tasks in parallel with
624	  the current vCPU is discounted from the vCPU power. To account for
625	  that, there can be a small performance impact.
626
627	  If in doubt, say N here.
628
629config PARAVIRT_CLOCK
630	bool
631
632endif #HYPERVISOR_GUEST
633
634config NO_BOOTMEM
635	def_bool y
636
637config MEMTEST
638	bool "Memtest"
639	---help---
640	  This option adds a kernel parameter 'memtest', which allows memtest
641	  to be set.
642	        memtest=0, mean disabled; -- default
643	        memtest=1, mean do 1 test pattern;
644	        ...
645	        memtest=4, mean do 4 test patterns.
646	  If you are unsure how to answer this question, answer N.
647
648source "arch/x86/Kconfig.cpu"
649
650config HPET_TIMER
651	def_bool X86_64
652	prompt "HPET Timer Support" if X86_32
653	---help---
654	  Use the IA-PC HPET (High Precision Event Timer) to manage
655	  time in preference to the PIT and RTC, if a HPET is
656	  present.
657	  HPET is the next generation timer replacing legacy 8254s.
658	  The HPET provides a stable time base on SMP
659	  systems, unlike the TSC, but it is more expensive to access,
660	  as it is off-chip.  You can find the HPET spec at
661	  <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
662
663	  You can safely choose Y here.  However, HPET will only be
664	  activated if the platform and the BIOS support this feature.
665	  Otherwise the 8254 will be used for timing services.
666
667	  Choose N to continue using the legacy 8254 timer.
668
669config HPET_EMULATE_RTC
670	def_bool y
671	depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
672
673config APB_TIMER
674       def_bool y if X86_INTEL_MID
675       prompt "Intel MID APB Timer Support" if X86_INTEL_MID
676       select DW_APB_TIMER
677       depends on X86_INTEL_MID && SFI
678       help
679         APB timer is the replacement for 8254, HPET on X86 MID platforms.
680         The APBT provides a stable time base on SMP
681         systems, unlike the TSC, but it is more expensive to access,
682         as it is off-chip. APB timers are always running regardless of CPU
683         C states, they are used as per CPU clockevent device when possible.
684
685# Mark as expert because too many people got it wrong.
686# The code disables itself when not needed.
687config DMI
688	default y
689	select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
690	bool "Enable DMI scanning" if EXPERT
691	---help---
692	  Enabled scanning of DMI to identify machine quirks. Say Y
693	  here unless you have verified that your setup is not
694	  affected by entries in the DMI blacklist. Required by PNP
695	  BIOS code.
696
697config GART_IOMMU
698	bool "Old AMD GART IOMMU support"
699	select SWIOTLB
700	depends on X86_64 && PCI && AMD_NB
701	---help---
702	  Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
703	  GART based hardware IOMMUs.
704
705	  The GART supports full DMA access for devices with 32-bit access
706	  limitations, on systems with more than 3 GB. This is usually needed
707	  for USB, sound, many IDE/SATA chipsets and some other devices.
708
709	  Newer systems typically have a modern AMD IOMMU, supported via
710	  the CONFIG_AMD_IOMMU=y config option.
711
712	  In normal configurations this driver is only active when needed:
713	  there's more than 3 GB of memory and the system contains a
714	  32-bit limited device.
715
716	  If unsure, say Y.
717
718config CALGARY_IOMMU
719	bool "IBM Calgary IOMMU support"
720	select SWIOTLB
721	depends on X86_64 && PCI
722	---help---
723	  Support for hardware IOMMUs in IBM's xSeries x366 and x460
724	  systems. Needed to run systems with more than 3GB of memory
725	  properly with 32-bit PCI devices that do not support DAC
726	  (Double Address Cycle). Calgary also supports bus level
727	  isolation, where all DMAs pass through the IOMMU.  This
728	  prevents them from going anywhere except their intended
729	  destination. This catches hard-to-find kernel bugs and
730	  mis-behaving drivers and devices that do not use the DMA-API
731	  properly to set up their DMA buffers.  The IOMMU can be
732	  turned off at boot time with the iommu=off parameter.
733	  Normally the kernel will make the right choice by itself.
734	  If unsure, say Y.
735
736config CALGARY_IOMMU_ENABLED_BY_DEFAULT
737	def_bool y
738	prompt "Should Calgary be enabled by default?"
739	depends on CALGARY_IOMMU
740	---help---
741	  Should Calgary be enabled by default? if you choose 'y', Calgary
742	  will be used (if it exists). If you choose 'n', Calgary will not be
743	  used even if it exists. If you choose 'n' and would like to use
744	  Calgary anyway, pass 'iommu=calgary' on the kernel command line.
745	  If unsure, say Y.
746
747# need this always selected by IOMMU for the VIA workaround
748config SWIOTLB
749	def_bool y if X86_64
750	---help---
751	  Support for software bounce buffers used on x86-64 systems
752	  which don't have a hardware IOMMU. Using this PCI devices
753	  which can only access 32-bits of memory can be used on systems
754	  with more than 3 GB of memory.
755	  If unsure, say Y.
756
757config IOMMU_HELPER
758	def_bool y
759	depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
760
761config MAXSMP
762	bool "Enable Maximum number of SMP Processors and NUMA Nodes"
763	depends on X86_64 && SMP && DEBUG_KERNEL
764	select CPUMASK_OFFSTACK
765	---help---
766	  Enable maximum number of CPUS and NUMA Nodes for this architecture.
767	  If unsure, say N.
768
769config NR_CPUS
770	int "Maximum number of CPUs" if SMP && !MAXSMP
771	range 2 8 if SMP && X86_32 && !X86_BIGSMP
772	range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
773	range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
774	default "1" if !SMP
775	default "8192" if MAXSMP
776	default "32" if SMP && X86_BIGSMP
777	default "8" if SMP
778	---help---
779	  This allows you to specify the maximum number of CPUs which this
780	  kernel will support.  If CPUMASK_OFFSTACK is enabled, the maximum
781	  supported value is 4096, otherwise the maximum value is 512.  The
782	  minimum value which makes sense is 2.
783
784	  This is purely to save memory - each supported CPU adds
785	  approximately eight kilobytes to the kernel image.
786
787config SCHED_SMT
788	bool "SMT (Hyperthreading) scheduler support"
789	depends on X86_HT
790	---help---
791	  SMT scheduler support improves the CPU scheduler's decision making
792	  when dealing with Intel Pentium 4 chips with HyperThreading at a
793	  cost of slightly increased overhead in some places. If unsure say
794	  N here.
795
796config SCHED_MC
797	def_bool y
798	prompt "Multi-core scheduler support"
799	depends on X86_HT
800	---help---
801	  Multi-core scheduler support improves the CPU scheduler's decision
802	  making when dealing with multi-core CPU chips at a cost of slightly
803	  increased overhead in some places. If unsure say N here.
804
805source "kernel/Kconfig.preempt"
806
807config X86_UP_APIC
808	bool "Local APIC support on uniprocessors"
809	depends on X86_32 && !SMP && !X86_32_NON_STANDARD && !PCI_MSI
810	---help---
811	  A local APIC (Advanced Programmable Interrupt Controller) is an
812	  integrated interrupt controller in the CPU. If you have a single-CPU
813	  system which has a processor with a local APIC, you can say Y here to
814	  enable and use it. If you say Y here even though your machine doesn't
815	  have a local APIC, then the kernel will still run with no slowdown at
816	  all. The local APIC supports CPU-generated self-interrupts (timer,
817	  performance counters), and the NMI watchdog which detects hard
818	  lockups.
819
820config X86_UP_IOAPIC
821	bool "IO-APIC support on uniprocessors"
822	depends on X86_UP_APIC
823	---help---
824	  An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
825	  SMP-capable replacement for PC-style interrupt controllers. Most
826	  SMP systems and many recent uniprocessor systems have one.
827
828	  If you have a single-CPU system with an IO-APIC, you can say Y here
829	  to use it. If you say Y here even though your machine doesn't have
830	  an IO-APIC, then the kernel will still run with no slowdown at all.
831
832config X86_LOCAL_APIC
833	def_bool y
834	depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
835
836config X86_IO_APIC
837	def_bool y
838	depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC || PCI_MSI
839	select GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
840
841config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
842	bool "Reroute for broken boot IRQs"
843	depends on X86_IO_APIC
844	---help---
845	  This option enables a workaround that fixes a source of
846	  spurious interrupts. This is recommended when threaded
847	  interrupt handling is used on systems where the generation of
848	  superfluous "boot interrupts" cannot be disabled.
849
850	  Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
851	  entry in the chipset's IO-APIC is masked (as, e.g. the RT
852	  kernel does during interrupt handling). On chipsets where this
853	  boot IRQ generation cannot be disabled, this workaround keeps
854	  the original IRQ line masked so that only the equivalent "boot
855	  IRQ" is delivered to the CPUs. The workaround also tells the
856	  kernel to set up the IRQ handler on the boot IRQ line. In this
857	  way only one interrupt is delivered to the kernel. Otherwise
858	  the spurious second interrupt may cause the kernel to bring
859	  down (vital) interrupt lines.
860
861	  Only affects "broken" chipsets. Interrupt sharing may be
862	  increased on these systems.
863
864config X86_MCE
865	bool "Machine Check / overheating reporting"
866	default y
867	---help---
868	  Machine Check support allows the processor to notify the
869	  kernel if it detects a problem (e.g. overheating, data corruption).
870	  The action the kernel takes depends on the severity of the problem,
871	  ranging from warning messages to halting the machine.
872
873config X86_MCE_INTEL
874	def_bool y
875	prompt "Intel MCE features"
876	depends on X86_MCE && X86_LOCAL_APIC
877	---help---
878	   Additional support for intel specific MCE features such as
879	   the thermal monitor.
880
881config X86_MCE_AMD
882	def_bool y
883	prompt "AMD MCE features"
884	depends on X86_MCE && X86_LOCAL_APIC
885	---help---
886	   Additional support for AMD specific MCE features such as
887	   the DRAM Error Threshold.
888
889config X86_ANCIENT_MCE
890	bool "Support for old Pentium 5 / WinChip machine checks"
891	depends on X86_32 && X86_MCE
892	---help---
893	  Include support for machine check handling on old Pentium 5 or WinChip
894	  systems. These typically need to be enabled explicitly on the command
895	  line.
896
897config X86_MCE_THRESHOLD
898	depends on X86_MCE_AMD || X86_MCE_INTEL
899	def_bool y
900
901config X86_MCE_INJECT
902	depends on X86_MCE
903	tristate "Machine check injector support"
904	---help---
905	  Provide support for injecting machine checks for testing purposes.
906	  If you don't know what a machine check is and you don't do kernel
907	  QA it is safe to say n.
908
909config X86_THERMAL_VECTOR
910	def_bool y
911	depends on X86_MCE_INTEL
912
913config VM86
914	bool "Enable VM86 support" if EXPERT
915	default y
916	depends on X86_32
917	---help---
918	  This option is required by programs like DOSEMU to run
919	  16-bit real mode legacy code on x86 processors. It also may
920	  be needed by software like XFree86 to initialize some video
921	  cards via BIOS. Disabling this option saves about 6K.
922
923config X86_16BIT
924	bool "Enable support for 16-bit segments" if EXPERT
925	default y
926	---help---
927	  This option is required by programs like Wine to run 16-bit
928	  protected mode legacy code on x86 processors.  Disabling
929	  this option saves about 300 bytes on i386, or around 6K text
930	  plus 16K runtime memory on x86-64,
931
932config X86_ESPFIX32
933	def_bool y
934	depends on X86_16BIT && X86_32
935
936config X86_ESPFIX64
937	def_bool y
938	depends on X86_16BIT && X86_64
939
940config TOSHIBA
941	tristate "Toshiba Laptop support"
942	depends on X86_32
943	---help---
944	  This adds a driver to safely access the System Management Mode of
945	  the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
946	  not work on models with a Phoenix BIOS. The System Management Mode
947	  is used to set the BIOS and power saving options on Toshiba portables.
948
949	  For information on utilities to make use of this driver see the
950	  Toshiba Linux utilities web site at:
951	  <http://www.buzzard.org.uk/toshiba/>.
952
953	  Say Y if you intend to run this kernel on a Toshiba portable.
954	  Say N otherwise.
955
956config I8K
957	tristate "Dell laptop support"
958	select HWMON
959	---help---
960	  This adds a driver to safely access the System Management Mode
961	  of the CPU on the Dell Inspiron 8000. The System Management Mode
962	  is used to read cpu temperature and cooling fan status and to
963	  control the fans on the I8K portables.
964
965	  This driver has been tested only on the Inspiron 8000 but it may
966	  also work with other Dell laptops. You can force loading on other
967	  models by passing the parameter `force=1' to the module. Use at
968	  your own risk.
969
970	  For information on utilities to make use of this driver see the
971	  I8K Linux utilities web site at:
972	  <http://people.debian.org/~dz/i8k/>
973
974	  Say Y if you intend to run this kernel on a Dell Inspiron 8000.
975	  Say N otherwise.
976
977config X86_REBOOTFIXUPS
978	bool "Enable X86 board specific fixups for reboot"
979	depends on X86_32
980	---help---
981	  This enables chipset and/or board specific fixups to be done
982	  in order to get reboot to work correctly. This is only needed on
983	  some combinations of hardware and BIOS. The symptom, for which
984	  this config is intended, is when reboot ends with a stalled/hung
985	  system.
986
987	  Currently, the only fixup is for the Geode machines using
988	  CS5530A and CS5536 chipsets and the RDC R-321x SoC.
989
990	  Say Y if you want to enable the fixup. Currently, it's safe to
991	  enable this option even if you don't need it.
992	  Say N otherwise.
993
994config MICROCODE
995	tristate "CPU microcode loading support"
996	depends on CPU_SUP_AMD || CPU_SUP_INTEL
997	select FW_LOADER
998	---help---
999
1000	  If you say Y here, you will be able to update the microcode on
1001	  certain Intel and AMD processors. The Intel support is for the
1002	  IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1003	  Xeon etc. The AMD support is for families 0x10 and later. You will
1004	  obviously need the actual microcode binary data itself which is not
1005	  shipped with the Linux kernel.
1006
1007	  This option selects the general module only, you need to select
1008	  at least one vendor specific module as well.
1009
1010	  To compile this driver as a module, choose M here: the module
1011	  will be called microcode.
1012
1013config MICROCODE_INTEL
1014	bool "Intel microcode loading support"
1015	depends on MICROCODE
1016	default MICROCODE
1017	select FW_LOADER
1018	---help---
1019	  This options enables microcode patch loading support for Intel
1020	  processors.
1021
1022	  For the current Intel microcode data package go to
1023	  <https://downloadcenter.intel.com> and search for
1024	  'Linux Processor Microcode Data File'.
1025
1026config MICROCODE_AMD
1027	bool "AMD microcode loading support"
1028	depends on MICROCODE
1029	select FW_LOADER
1030	---help---
1031	  If you select this option, microcode patch loading support for AMD
1032	  processors will be enabled.
1033
1034config MICROCODE_OLD_INTERFACE
1035	def_bool y
1036	depends on MICROCODE
1037
1038config MICROCODE_INTEL_EARLY
1039	def_bool n
1040
1041config MICROCODE_AMD_EARLY
1042	def_bool n
1043
1044config MICROCODE_EARLY
1045	bool "Early load microcode"
1046	depends on MICROCODE=y && BLK_DEV_INITRD
1047	select MICROCODE_INTEL_EARLY if MICROCODE_INTEL
1048	select MICROCODE_AMD_EARLY if MICROCODE_AMD
1049	default y
1050	help
1051	  This option provides functionality to read additional microcode data
1052	  at the beginning of initrd image. The data tells kernel to load
1053	  microcode to CPU's as early as possible. No functional change if no
1054	  microcode data is glued to the initrd, therefore it's safe to say Y.
1055
1056config X86_MSR
1057	tristate "/dev/cpu/*/msr - Model-specific register support"
1058	---help---
1059	  This device gives privileged processes access to the x86
1060	  Model-Specific Registers (MSRs).  It is a character device with
1061	  major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1062	  MSR accesses are directed to a specific CPU on multi-processor
1063	  systems.
1064
1065config X86_CPUID
1066	tristate "/dev/cpu/*/cpuid - CPU information support"
1067	---help---
1068	  This device gives processes access to the x86 CPUID instruction to
1069	  be executed on a specific processor.  It is a character device
1070	  with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1071	  /dev/cpu/31/cpuid.
1072
1073choice
1074	prompt "High Memory Support"
1075	default HIGHMEM4G
1076	depends on X86_32
1077
1078config NOHIGHMEM
1079	bool "off"
1080	---help---
1081	  Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1082	  However, the address space of 32-bit x86 processors is only 4
1083	  Gigabytes large. That means that, if you have a large amount of
1084	  physical memory, not all of it can be "permanently mapped" by the
1085	  kernel. The physical memory that's not permanently mapped is called
1086	  "high memory".
1087
1088	  If you are compiling a kernel which will never run on a machine with
1089	  more than 1 Gigabyte total physical RAM, answer "off" here (default
1090	  choice and suitable for most users). This will result in a "3GB/1GB"
1091	  split: 3GB are mapped so that each process sees a 3GB virtual memory
1092	  space and the remaining part of the 4GB virtual memory space is used
1093	  by the kernel to permanently map as much physical memory as
1094	  possible.
1095
1096	  If the machine has between 1 and 4 Gigabytes physical RAM, then
1097	  answer "4GB" here.
1098
1099	  If more than 4 Gigabytes is used then answer "64GB" here. This
1100	  selection turns Intel PAE (Physical Address Extension) mode on.
1101	  PAE implements 3-level paging on IA32 processors. PAE is fully
1102	  supported by Linux, PAE mode is implemented on all recent Intel
1103	  processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1104	  then the kernel will not boot on CPUs that don't support PAE!
1105
1106	  The actual amount of total physical memory will either be
1107	  auto detected or can be forced by using a kernel command line option
1108	  such as "mem=256M". (Try "man bootparam" or see the documentation of
1109	  your boot loader (lilo or loadlin) about how to pass options to the
1110	  kernel at boot time.)
1111
1112	  If unsure, say "off".
1113
1114config HIGHMEM4G
1115	bool "4GB"
1116	---help---
1117	  Select this if you have a 32-bit processor and between 1 and 4
1118	  gigabytes of physical RAM.
1119
1120config HIGHMEM64G
1121	bool "64GB"
1122	depends on !M486
1123	select X86_PAE
1124	---help---
1125	  Select this if you have a 32-bit processor and more than 4
1126	  gigabytes of physical RAM.
1127
1128endchoice
1129
1130choice
1131	prompt "Memory split" if EXPERT
1132	default VMSPLIT_3G
1133	depends on X86_32
1134	---help---
1135	  Select the desired split between kernel and user memory.
1136
1137	  If the address range available to the kernel is less than the
1138	  physical memory installed, the remaining memory will be available
1139	  as "high memory". Accessing high memory is a little more costly
1140	  than low memory, as it needs to be mapped into the kernel first.
1141	  Note that increasing the kernel address space limits the range
1142	  available to user programs, making the address space there
1143	  tighter.  Selecting anything other than the default 3G/1G split
1144	  will also likely make your kernel incompatible with binary-only
1145	  kernel modules.
1146
1147	  If you are not absolutely sure what you are doing, leave this
1148	  option alone!
1149
1150	config VMSPLIT_3G
1151		bool "3G/1G user/kernel split"
1152	config VMSPLIT_3G_OPT
1153		depends on !X86_PAE
1154		bool "3G/1G user/kernel split (for full 1G low memory)"
1155	config VMSPLIT_2G
1156		bool "2G/2G user/kernel split"
1157	config VMSPLIT_2G_OPT
1158		depends on !X86_PAE
1159		bool "2G/2G user/kernel split (for full 2G low memory)"
1160	config VMSPLIT_1G
1161		bool "1G/3G user/kernel split"
1162endchoice
1163
1164config PAGE_OFFSET
1165	hex
1166	default 0xB0000000 if VMSPLIT_3G_OPT
1167	default 0x80000000 if VMSPLIT_2G
1168	default 0x78000000 if VMSPLIT_2G_OPT
1169	default 0x40000000 if VMSPLIT_1G
1170	default 0xC0000000
1171	depends on X86_32
1172
1173config HIGHMEM
1174	def_bool y
1175	depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1176
1177config X86_PAE
1178	bool "PAE (Physical Address Extension) Support"
1179	depends on X86_32 && !HIGHMEM4G
1180	---help---
1181	  PAE is required for NX support, and furthermore enables
1182	  larger swapspace support for non-overcommit purposes. It
1183	  has the cost of more pagetable lookup overhead, and also
1184	  consumes more pagetable space per process.
1185
1186config ARCH_PHYS_ADDR_T_64BIT
1187	def_bool y
1188	depends on X86_64 || X86_PAE
1189
1190config ARCH_DMA_ADDR_T_64BIT
1191	def_bool y
1192	depends on X86_64 || HIGHMEM64G
1193
1194config DIRECT_GBPAGES
1195	bool "Enable 1GB pages for kernel pagetables" if EXPERT
1196	default y
1197	depends on X86_64
1198	---help---
1199	  Allow the kernel linear mapping to use 1GB pages on CPUs that
1200	  support it. This can improve the kernel's performance a tiny bit by
1201	  reducing TLB pressure. If in doubt, say "Y".
1202
1203# Common NUMA Features
1204config NUMA
1205	bool "Numa Memory Allocation and Scheduler Support"
1206	depends on SMP
1207	depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1208	default y if X86_BIGSMP
1209	---help---
1210	  Enable NUMA (Non Uniform Memory Access) support.
1211
1212	  The kernel will try to allocate memory used by a CPU on the
1213	  local memory controller of the CPU and add some more
1214	  NUMA awareness to the kernel.
1215
1216	  For 64-bit this is recommended if the system is Intel Core i7
1217	  (or later), AMD Opteron, or EM64T NUMA.
1218
1219	  For 32-bit this is only needed if you boot a 32-bit
1220	  kernel on a 64-bit NUMA platform.
1221
1222	  Otherwise, you should say N.
1223
1224config AMD_NUMA
1225	def_bool y
1226	prompt "Old style AMD Opteron NUMA detection"
1227	depends on X86_64 && NUMA && PCI
1228	---help---
1229	  Enable AMD NUMA node topology detection.  You should say Y here if
1230	  you have a multi processor AMD system. This uses an old method to
1231	  read the NUMA configuration directly from the builtin Northbridge
1232	  of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1233	  which also takes priority if both are compiled in.
1234
1235config X86_64_ACPI_NUMA
1236	def_bool y
1237	prompt "ACPI NUMA detection"
1238	depends on X86_64 && NUMA && ACPI && PCI
1239	select ACPI_NUMA
1240	---help---
1241	  Enable ACPI SRAT based node topology detection.
1242
1243# Some NUMA nodes have memory ranges that span
1244# other nodes.  Even though a pfn is valid and
1245# between a node's start and end pfns, it may not
1246# reside on that node.  See memmap_init_zone()
1247# for details.
1248config NODES_SPAN_OTHER_NODES
1249	def_bool y
1250	depends on X86_64_ACPI_NUMA
1251
1252config NUMA_EMU
1253	bool "NUMA emulation"
1254	depends on NUMA
1255	---help---
1256	  Enable NUMA emulation. A flat machine will be split
1257	  into virtual nodes when booted with "numa=fake=N", where N is the
1258	  number of nodes. This is only useful for debugging.
1259
1260config NODES_SHIFT
1261	int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1262	range 1 10
1263	default "10" if MAXSMP
1264	default "6" if X86_64
1265	default "3"
1266	depends on NEED_MULTIPLE_NODES
1267	---help---
1268	  Specify the maximum number of NUMA Nodes available on the target
1269	  system.  Increases memory reserved to accommodate various tables.
1270
1271config ARCH_HAVE_MEMORY_PRESENT
1272	def_bool y
1273	depends on X86_32 && DISCONTIGMEM
1274
1275config NEED_NODE_MEMMAP_SIZE
1276	def_bool y
1277	depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1278
1279config ARCH_FLATMEM_ENABLE
1280	def_bool y
1281	depends on X86_32 && !NUMA
1282
1283config ARCH_DISCONTIGMEM_ENABLE
1284	def_bool y
1285	depends on NUMA && X86_32
1286
1287config ARCH_DISCONTIGMEM_DEFAULT
1288	def_bool y
1289	depends on NUMA && X86_32
1290
1291config ARCH_SPARSEMEM_ENABLE
1292	def_bool y
1293	depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1294	select SPARSEMEM_STATIC if X86_32
1295	select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1296
1297config ARCH_SPARSEMEM_DEFAULT
1298	def_bool y
1299	depends on X86_64
1300
1301config ARCH_SELECT_MEMORY_MODEL
1302	def_bool y
1303	depends on ARCH_SPARSEMEM_ENABLE
1304
1305config ARCH_MEMORY_PROBE
1306	bool "Enable sysfs memory/probe interface"
1307	depends on X86_64 && MEMORY_HOTPLUG
1308	help
1309	  This option enables a sysfs memory/probe interface for testing.
1310	  See Documentation/memory-hotplug.txt for more information.
1311	  If you are unsure how to answer this question, answer N.
1312
1313config ARCH_PROC_KCORE_TEXT
1314	def_bool y
1315	depends on X86_64 && PROC_KCORE
1316
1317config ILLEGAL_POINTER_VALUE
1318       hex
1319       default 0 if X86_32
1320       default 0xdead000000000000 if X86_64
1321
1322source "mm/Kconfig"
1323
1324config HIGHPTE
1325	bool "Allocate 3rd-level pagetables from highmem"
1326	depends on HIGHMEM
1327	---help---
1328	  The VM uses one page table entry for each page of physical memory.
1329	  For systems with a lot of RAM, this can be wasteful of precious
1330	  low memory.  Setting this option will put user-space page table
1331	  entries in high memory.
1332
1333config X86_CHECK_BIOS_CORRUPTION
1334	bool "Check for low memory corruption"
1335	---help---
1336	  Periodically check for memory corruption in low memory, which
1337	  is suspected to be caused by BIOS.  Even when enabled in the
1338	  configuration, it is disabled at runtime.  Enable it by
1339	  setting "memory_corruption_check=1" on the kernel command
1340	  line.  By default it scans the low 64k of memory every 60
1341	  seconds; see the memory_corruption_check_size and
1342	  memory_corruption_check_period parameters in
1343	  Documentation/kernel-parameters.txt to adjust this.
1344
1345	  When enabled with the default parameters, this option has
1346	  almost no overhead, as it reserves a relatively small amount
1347	  of memory and scans it infrequently.  It both detects corruption
1348	  and prevents it from affecting the running system.
1349
1350	  It is, however, intended as a diagnostic tool; if repeatable
1351	  BIOS-originated corruption always affects the same memory,
1352	  you can use memmap= to prevent the kernel from using that
1353	  memory.
1354
1355config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1356	bool "Set the default setting of memory_corruption_check"
1357	depends on X86_CHECK_BIOS_CORRUPTION
1358	default y
1359	---help---
1360	  Set whether the default state of memory_corruption_check is
1361	  on or off.
1362
1363config X86_RESERVE_LOW
1364	int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1365	default 64
1366	range 4 640
1367	---help---
1368	  Specify the amount of low memory to reserve for the BIOS.
1369
1370	  The first page contains BIOS data structures that the kernel
1371	  must not use, so that page must always be reserved.
1372
1373	  By default we reserve the first 64K of physical RAM, as a
1374	  number of BIOSes are known to corrupt that memory range
1375	  during events such as suspend/resume or monitor cable
1376	  insertion, so it must not be used by the kernel.
1377
1378	  You can set this to 4 if you are absolutely sure that you
1379	  trust the BIOS to get all its memory reservations and usages
1380	  right.  If you know your BIOS have problems beyond the
1381	  default 64K area, you can set this to 640 to avoid using the
1382	  entire low memory range.
1383
1384	  If you have doubts about the BIOS (e.g. suspend/resume does
1385	  not work or there's kernel crashes after certain hardware
1386	  hotplug events) then you might want to enable
1387	  X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1388	  typical corruption patterns.
1389
1390	  Leave this to the default value of 64 if you are unsure.
1391
1392config MATH_EMULATION
1393	bool
1394	prompt "Math emulation" if X86_32
1395	---help---
1396	  Linux can emulate a math coprocessor (used for floating point
1397	  operations) if you don't have one. 486DX and Pentium processors have
1398	  a math coprocessor built in, 486SX and 386 do not, unless you added
1399	  a 487DX or 387, respectively. (The messages during boot time can
1400	  give you some hints here ["man dmesg"].) Everyone needs either a
1401	  coprocessor or this emulation.
1402
1403	  If you don't have a math coprocessor, you need to say Y here; if you
1404	  say Y here even though you have a coprocessor, the coprocessor will
1405	  be used nevertheless. (This behavior can be changed with the kernel
1406	  command line option "no387", which comes handy if your coprocessor
1407	  is broken. Try "man bootparam" or see the documentation of your boot
1408	  loader (lilo or loadlin) about how to pass options to the kernel at
1409	  boot time.) This means that it is a good idea to say Y here if you
1410	  intend to use this kernel on different machines.
1411
1412	  More information about the internals of the Linux math coprocessor
1413	  emulation can be found in <file:arch/x86/math-emu/README>.
1414
1415	  If you are not sure, say Y; apart from resulting in a 66 KB bigger
1416	  kernel, it won't hurt.
1417
1418config MTRR
1419	def_bool y
1420	prompt "MTRR (Memory Type Range Register) support" if EXPERT
1421	---help---
1422	  On Intel P6 family processors (Pentium Pro, Pentium II and later)
1423	  the Memory Type Range Registers (MTRRs) may be used to control
1424	  processor access to memory ranges. This is most useful if you have
1425	  a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1426	  allows bus write transfers to be combined into a larger transfer
1427	  before bursting over the PCI/AGP bus. This can increase performance
1428	  of image write operations 2.5 times or more. Saying Y here creates a
1429	  /proc/mtrr file which may be used to manipulate your processor's
1430	  MTRRs. Typically the X server should use this.
1431
1432	  This code has a reasonably generic interface so that similar
1433	  control registers on other processors can be easily supported
1434	  as well:
1435
1436	  The Cyrix 6x86, 6x86MX and M II processors have Address Range
1437	  Registers (ARRs) which provide a similar functionality to MTRRs. For
1438	  these, the ARRs are used to emulate the MTRRs.
1439	  The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1440	  MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1441	  write-combining. All of these processors are supported by this code
1442	  and it makes sense to say Y here if you have one of them.
1443
1444	  Saying Y here also fixes a problem with buggy SMP BIOSes which only
1445	  set the MTRRs for the boot CPU and not for the secondary CPUs. This
1446	  can lead to all sorts of problems, so it's good to say Y here.
1447
1448	  You can safely say Y even if your machine doesn't have MTRRs, you'll
1449	  just add about 9 KB to your kernel.
1450
1451	  See <file:Documentation/x86/mtrr.txt> for more information.
1452
1453config MTRR_SANITIZER
1454	def_bool y
1455	prompt "MTRR cleanup support"
1456	depends on MTRR
1457	---help---
1458	  Convert MTRR layout from continuous to discrete, so X drivers can
1459	  add writeback entries.
1460
1461	  Can be disabled with disable_mtrr_cleanup on the kernel command line.
1462	  The largest mtrr entry size for a continuous block can be set with
1463	  mtrr_chunk_size.
1464
1465	  If unsure, say Y.
1466
1467config MTRR_SANITIZER_ENABLE_DEFAULT
1468	int "MTRR cleanup enable value (0-1)"
1469	range 0 1
1470	default "0"
1471	depends on MTRR_SANITIZER
1472	---help---
1473	  Enable mtrr cleanup default value
1474
1475config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1476	int "MTRR cleanup spare reg num (0-7)"
1477	range 0 7
1478	default "1"
1479	depends on MTRR_SANITIZER
1480	---help---
1481	  mtrr cleanup spare entries default, it can be changed via
1482	  mtrr_spare_reg_nr=N on the kernel command line.
1483
1484config X86_PAT
1485	def_bool y
1486	prompt "x86 PAT support" if EXPERT
1487	depends on MTRR
1488	---help---
1489	  Use PAT attributes to setup page level cache control.
1490
1491	  PATs are the modern equivalents of MTRRs and are much more
1492	  flexible than MTRRs.
1493
1494	  Say N here if you see bootup problems (boot crash, boot hang,
1495	  spontaneous reboots) or a non-working video driver.
1496
1497	  If unsure, say Y.
1498
1499config ARCH_USES_PG_UNCACHED
1500	def_bool y
1501	depends on X86_PAT
1502
1503config ARCH_RANDOM
1504	def_bool y
1505	prompt "x86 architectural random number generator" if EXPERT
1506	---help---
1507	  Enable the x86 architectural RDRAND instruction
1508	  (Intel Bull Mountain technology) to generate random numbers.
1509	  If supported, this is a high bandwidth, cryptographically
1510	  secure hardware random number generator.
1511
1512config X86_SMAP
1513	def_bool y
1514	prompt "Supervisor Mode Access Prevention" if EXPERT
1515	---help---
1516	  Supervisor Mode Access Prevention (SMAP) is a security
1517	  feature in newer Intel processors.  There is a small
1518	  performance cost if this enabled and turned on; there is
1519	  also a small increase in the kernel size if this is enabled.
1520
1521	  If unsure, say Y.
1522
1523config EFI
1524	bool "EFI runtime service support"
1525	depends on ACPI
1526	select UCS2_STRING
1527	select EFI_RUNTIME_WRAPPERS
1528	---help---
1529	  This enables the kernel to use EFI runtime services that are
1530	  available (such as the EFI variable services).
1531
1532	  This option is only useful on systems that have EFI firmware.
1533	  In addition, you should use the latest ELILO loader available
1534	  at <http://elilo.sourceforge.net> in order to take advantage
1535	  of EFI runtime services. However, even with this option, the
1536	  resultant kernel should continue to boot on existing non-EFI
1537	  platforms.
1538
1539config EFI_STUB
1540       bool "EFI stub support"
1541       depends on EFI
1542       ---help---
1543          This kernel feature allows a bzImage to be loaded directly
1544	  by EFI firmware without the use of a bootloader.
1545
1546	  See Documentation/efi-stub.txt for more information.
1547
1548config EFI_MIXED
1549	bool "EFI mixed-mode support"
1550	depends on EFI_STUB && X86_64
1551	---help---
1552	   Enabling this feature allows a 64-bit kernel to be booted
1553	   on a 32-bit firmware, provided that your CPU supports 64-bit
1554	   mode.
1555
1556	   Note that it is not possible to boot a mixed-mode enabled
1557	   kernel via the EFI boot stub - a bootloader that supports
1558	   the EFI handover protocol must be used.
1559
1560	   If unsure, say N.
1561
1562config SECCOMP
1563	def_bool y
1564	prompt "Enable seccomp to safely compute untrusted bytecode"
1565	---help---
1566	  This kernel feature is useful for number crunching applications
1567	  that may need to compute untrusted bytecode during their
1568	  execution. By using pipes or other transports made available to
1569	  the process as file descriptors supporting the read/write
1570	  syscalls, it's possible to isolate those applications in
1571	  their own address space using seccomp. Once seccomp is
1572	  enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1573	  and the task is only allowed to execute a few safe syscalls
1574	  defined by each seccomp mode.
1575
1576	  If unsure, say Y. Only embedded should say N here.
1577
1578source kernel/Kconfig.hz
1579
1580config KEXEC
1581	bool "kexec system call"
1582	---help---
1583	  kexec is a system call that implements the ability to shutdown your
1584	  current kernel, and to start another kernel.  It is like a reboot
1585	  but it is independent of the system firmware.   And like a reboot
1586	  you can start any kernel with it, not just Linux.
1587
1588	  The name comes from the similarity to the exec system call.
1589
1590	  It is an ongoing process to be certain the hardware in a machine
1591	  is properly shutdown, so do not be surprised if this code does not
1592	  initially work for you.  As of this writing the exact hardware
1593	  interface is strongly in flux, so no good recommendation can be
1594	  made.
1595
1596config CRASH_DUMP
1597	bool "kernel crash dumps"
1598	depends on X86_64 || (X86_32 && HIGHMEM)
1599	---help---
1600	  Generate crash dump after being started by kexec.
1601	  This should be normally only set in special crash dump kernels
1602	  which are loaded in the main kernel with kexec-tools into
1603	  a specially reserved region and then later executed after
1604	  a crash by kdump/kexec. The crash dump kernel must be compiled
1605	  to a memory address not used by the main kernel or BIOS using
1606	  PHYSICAL_START, or it must be built as a relocatable image
1607	  (CONFIG_RELOCATABLE=y).
1608	  For more details see Documentation/kdump/kdump.txt
1609
1610config KEXEC_JUMP
1611	bool "kexec jump"
1612	depends on KEXEC && HIBERNATION
1613	---help---
1614	  Jump between original kernel and kexeced kernel and invoke
1615	  code in physical address mode via KEXEC
1616
1617config PHYSICAL_START
1618	hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1619	default "0x1000000"
1620	---help---
1621	  This gives the physical address where the kernel is loaded.
1622
1623	  If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1624	  bzImage will decompress itself to above physical address and
1625	  run from there. Otherwise, bzImage will run from the address where
1626	  it has been loaded by the boot loader and will ignore above physical
1627	  address.
1628
1629	  In normal kdump cases one does not have to set/change this option
1630	  as now bzImage can be compiled as a completely relocatable image
1631	  (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1632	  address. This option is mainly useful for the folks who don't want
1633	  to use a bzImage for capturing the crash dump and want to use a
1634	  vmlinux instead. vmlinux is not relocatable hence a kernel needs
1635	  to be specifically compiled to run from a specific memory area
1636	  (normally a reserved region) and this option comes handy.
1637
1638	  So if you are using bzImage for capturing the crash dump,
1639	  leave the value here unchanged to 0x1000000 and set
1640	  CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
1641	  for capturing the crash dump change this value to start of
1642	  the reserved region.  In other words, it can be set based on
1643	  the "X" value as specified in the "crashkernel=YM@XM"
1644	  command line boot parameter passed to the panic-ed
1645	  kernel. Please take a look at Documentation/kdump/kdump.txt
1646	  for more details about crash dumps.
1647
1648	  Usage of bzImage for capturing the crash dump is recommended as
1649	  one does not have to build two kernels. Same kernel can be used
1650	  as production kernel and capture kernel. Above option should have
1651	  gone away after relocatable bzImage support is introduced. But it
1652	  is present because there are users out there who continue to use
1653	  vmlinux for dump capture. This option should go away down the
1654	  line.
1655
1656	  Don't change this unless you know what you are doing.
1657
1658config RELOCATABLE
1659	bool "Build a relocatable kernel"
1660	default y
1661	---help---
1662	  This builds a kernel image that retains relocation information
1663	  so it can be loaded someplace besides the default 1MB.
1664	  The relocations tend to make the kernel binary about 10% larger,
1665	  but are discarded at runtime.
1666
1667	  One use is for the kexec on panic case where the recovery kernel
1668	  must live at a different physical address than the primary
1669	  kernel.
1670
1671	  Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1672	  it has been loaded at and the compile time physical address
1673	  (CONFIG_PHYSICAL_START) is used as the minimum location.
1674
1675config RANDOMIZE_BASE
1676	bool "Randomize the address of the kernel image"
1677	depends on RELOCATABLE
1678	default n
1679	---help---
1680	   Randomizes the physical and virtual address at which the
1681	   kernel image is decompressed, as a security feature that
1682	   deters exploit attempts relying on knowledge of the location
1683	   of kernel internals.
1684
1685	   Entropy is generated using the RDRAND instruction if it is
1686	   supported. If RDTSC is supported, it is used as well. If
1687	   neither RDRAND nor RDTSC are supported, then randomness is
1688	   read from the i8254 timer.
1689
1690	   The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
1691	   and aligned according to PHYSICAL_ALIGN. Since the kernel is
1692	   built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
1693	   minimum of 2MiB, only 10 bits of entropy is theoretically
1694	   possible. At best, due to page table layouts, 64-bit can use
1695	   9 bits of entropy and 32-bit uses 8 bits.
1696
1697	   If unsure, say N.
1698
1699config RANDOMIZE_BASE_MAX_OFFSET
1700	hex "Maximum kASLR offset allowed" if EXPERT
1701	depends on RANDOMIZE_BASE
1702	range 0x0 0x20000000 if X86_32
1703	default "0x20000000" if X86_32
1704	range 0x0 0x40000000 if X86_64
1705	default "0x40000000" if X86_64
1706	---help---
1707	  The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
1708	  memory is used to determine the maximal offset in bytes that will
1709	  be applied to the kernel when kernel Address Space Layout
1710	  Randomization (kASLR) is active. This must be a multiple of
1711	  PHYSICAL_ALIGN.
1712
1713	  On 32-bit this is limited to 512MiB by page table layouts. The
1714	  default is 512MiB.
1715
1716	  On 64-bit this is limited by how the kernel fixmap page table is
1717	  positioned, so this cannot be larger than 1GiB currently. Without
1718	  RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
1719	  and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
1720	  modules area will shrink to compensate, up to the current maximum
1721	  1GiB to 1GiB split. The default is 1GiB.
1722
1723	  If unsure, leave at the default value.
1724
1725# Relocation on x86 needs some additional build support
1726config X86_NEED_RELOCS
1727	def_bool y
1728	depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
1729
1730config PHYSICAL_ALIGN
1731	hex "Alignment value to which kernel should be aligned"
1732	default "0x200000"
1733	range 0x2000 0x1000000 if X86_32
1734	range 0x200000 0x1000000 if X86_64
1735	---help---
1736	  This value puts the alignment restrictions on physical address
1737	  where kernel is loaded and run from. Kernel is compiled for an
1738	  address which meets above alignment restriction.
1739
1740	  If bootloader loads the kernel at a non-aligned address and
1741	  CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1742	  address aligned to above value and run from there.
1743
1744	  If bootloader loads the kernel at a non-aligned address and
1745	  CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1746	  load address and decompress itself to the address it has been
1747	  compiled for and run from there. The address for which kernel is
1748	  compiled already meets above alignment restrictions. Hence the
1749	  end result is that kernel runs from a physical address meeting
1750	  above alignment restrictions.
1751
1752	  On 32-bit this value must be a multiple of 0x2000. On 64-bit
1753	  this value must be a multiple of 0x200000.
1754
1755	  Don't change this unless you know what you are doing.
1756
1757config HOTPLUG_CPU
1758	bool "Support for hot-pluggable CPUs"
1759	depends on SMP
1760	---help---
1761	  Say Y here to allow turning CPUs off and on. CPUs can be
1762	  controlled through /sys/devices/system/cpu.
1763	  ( Note: power management support will enable this option
1764	    automatically on SMP systems. )
1765	  Say N if you want to disable CPU hotplug.
1766
1767config BOOTPARAM_HOTPLUG_CPU0
1768	bool "Set default setting of cpu0_hotpluggable"
1769	default n
1770	depends on HOTPLUG_CPU
1771	---help---
1772	  Set whether default state of cpu0_hotpluggable is on or off.
1773
1774	  Say Y here to enable CPU0 hotplug by default. If this switch
1775	  is turned on, there is no need to give cpu0_hotplug kernel
1776	  parameter and the CPU0 hotplug feature is enabled by default.
1777
1778	  Please note: there are two known CPU0 dependencies if you want
1779	  to enable the CPU0 hotplug feature either by this switch or by
1780	  cpu0_hotplug kernel parameter.
1781
1782	  First, resume from hibernate or suspend always starts from CPU0.
1783	  So hibernate and suspend are prevented if CPU0 is offline.
1784
1785	  Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1786	  offline if any interrupt can not migrate out of CPU0. There may
1787	  be other CPU0 dependencies.
1788
1789	  Please make sure the dependencies are under your control before
1790	  you enable this feature.
1791
1792	  Say N if you don't want to enable CPU0 hotplug feature by default.
1793	  You still can enable the CPU0 hotplug feature at boot by kernel
1794	  parameter cpu0_hotplug.
1795
1796config DEBUG_HOTPLUG_CPU0
1797	def_bool n
1798	prompt "Debug CPU0 hotplug"
1799	depends on HOTPLUG_CPU
1800	---help---
1801	  Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1802	  soon as possible and boots up userspace with CPU0 offlined. User
1803	  can online CPU0 back after boot time.
1804
1805	  To debug CPU0 hotplug, you need to enable CPU0 offline/online
1806	  feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
1807	  compilation or giving cpu0_hotplug kernel parameter at boot.
1808
1809	  If unsure, say N.
1810
1811config COMPAT_VDSO
1812	def_bool n
1813	prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
1814	depends on X86_32 || IA32_EMULATION
1815	---help---
1816	  Certain buggy versions of glibc will crash if they are
1817	  presented with a 32-bit vDSO that is not mapped at the address
1818	  indicated in its segment table.
1819
1820	  The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
1821	  and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
1822	  49ad572a70b8aeb91e57483a11dd1b77e31c4468.  Glibc 2.3.3 is
1823	  the only released version with the bug, but OpenSUSE 9
1824	  contains a buggy "glibc 2.3.2".
1825
1826	  The symptom of the bug is that everything crashes on startup, saying:
1827	  dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
1828
1829	  Saying Y here changes the default value of the vdso32 boot
1830	  option from 1 to 0, which turns off the 32-bit vDSO entirely.
1831	  This works around the glibc bug but hurts performance.
1832
1833	  If unsure, say N: if you are compiling your own kernel, you
1834	  are unlikely to be using a buggy version of glibc.
1835
1836config CMDLINE_BOOL
1837	bool "Built-in kernel command line"
1838	---help---
1839	  Allow for specifying boot arguments to the kernel at
1840	  build time.  On some systems (e.g. embedded ones), it is
1841	  necessary or convenient to provide some or all of the
1842	  kernel boot arguments with the kernel itself (that is,
1843	  to not rely on the boot loader to provide them.)
1844
1845	  To compile command line arguments into the kernel,
1846	  set this option to 'Y', then fill in the
1847	  the boot arguments in CONFIG_CMDLINE.
1848
1849	  Systems with fully functional boot loaders (i.e. non-embedded)
1850	  should leave this option set to 'N'.
1851
1852config CMDLINE
1853	string "Built-in kernel command string"
1854	depends on CMDLINE_BOOL
1855	default ""
1856	---help---
1857	  Enter arguments here that should be compiled into the kernel
1858	  image and used at boot time.  If the boot loader provides a
1859	  command line at boot time, it is appended to this string to
1860	  form the full kernel command line, when the system boots.
1861
1862	  However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1863	  change this behavior.
1864
1865	  In most cases, the command line (whether built-in or provided
1866	  by the boot loader) should specify the device for the root
1867	  file system.
1868
1869config CMDLINE_OVERRIDE
1870	bool "Built-in command line overrides boot loader arguments"
1871	depends on CMDLINE_BOOL
1872	---help---
1873	  Set this option to 'Y' to have the kernel ignore the boot loader
1874	  command line, and use ONLY the built-in command line.
1875
1876	  This is used to work around broken boot loaders.  This should
1877	  be set to 'N' under normal conditions.
1878
1879endmenu
1880
1881config ARCH_ENABLE_MEMORY_HOTPLUG
1882	def_bool y
1883	depends on X86_64 || (X86_32 && HIGHMEM)
1884
1885config ARCH_ENABLE_MEMORY_HOTREMOVE
1886	def_bool y
1887	depends on MEMORY_HOTPLUG
1888
1889config USE_PERCPU_NUMA_NODE_ID
1890	def_bool y
1891	depends on NUMA
1892
1893config ARCH_ENABLE_SPLIT_PMD_PTLOCK
1894	def_bool y
1895	depends on X86_64 || X86_PAE
1896
1897config ARCH_ENABLE_HUGEPAGE_MIGRATION
1898	def_bool y
1899	depends on X86_64 && HUGETLB_PAGE && MIGRATION
1900
1901menu "Power management and ACPI options"
1902
1903config ARCH_HIBERNATION_HEADER
1904	def_bool y
1905	depends on X86_64 && HIBERNATION
1906
1907source "kernel/power/Kconfig"
1908
1909source "drivers/acpi/Kconfig"
1910
1911source "drivers/sfi/Kconfig"
1912
1913config X86_APM_BOOT
1914	def_bool y
1915	depends on APM
1916
1917menuconfig APM
1918	tristate "APM (Advanced Power Management) BIOS support"
1919	depends on X86_32 && PM_SLEEP
1920	---help---
1921	  APM is a BIOS specification for saving power using several different
1922	  techniques. This is mostly useful for battery powered laptops with
1923	  APM compliant BIOSes. If you say Y here, the system time will be
1924	  reset after a RESUME operation, the /proc/apm device will provide
1925	  battery status information, and user-space programs will receive
1926	  notification of APM "events" (e.g. battery status change).
1927
1928	  If you select "Y" here, you can disable actual use of the APM
1929	  BIOS by passing the "apm=off" option to the kernel at boot time.
1930
1931	  Note that the APM support is almost completely disabled for
1932	  machines with more than one CPU.
1933
1934	  In order to use APM, you will need supporting software. For location
1935	  and more information, read <file:Documentation/power/apm-acpi.txt>
1936	  and the Battery Powered Linux mini-HOWTO, available from
1937	  <http://www.tldp.org/docs.html#howto>.
1938
1939	  This driver does not spin down disk drives (see the hdparm(8)
1940	  manpage ("man 8 hdparm") for that), and it doesn't turn off
1941	  VESA-compliant "green" monitors.
1942
1943	  This driver does not support the TI 4000M TravelMate and the ACER
1944	  486/DX4/75 because they don't have compliant BIOSes. Many "green"
1945	  desktop machines also don't have compliant BIOSes, and this driver
1946	  may cause those machines to panic during the boot phase.
1947
1948	  Generally, if you don't have a battery in your machine, there isn't
1949	  much point in using this driver and you should say N. If you get
1950	  random kernel OOPSes or reboots that don't seem to be related to
1951	  anything, try disabling/enabling this option (or disabling/enabling
1952	  APM in your BIOS).
1953
1954	  Some other things you should try when experiencing seemingly random,
1955	  "weird" problems:
1956
1957	  1) make sure that you have enough swap space and that it is
1958	  enabled.
1959	  2) pass the "no-hlt" option to the kernel
1960	  3) switch on floating point emulation in the kernel and pass
1961	  the "no387" option to the kernel
1962	  4) pass the "floppy=nodma" option to the kernel
1963	  5) pass the "mem=4M" option to the kernel (thereby disabling
1964	  all but the first 4 MB of RAM)
1965	  6) make sure that the CPU is not over clocked.
1966	  7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1967	  8) disable the cache from your BIOS settings
1968	  9) install a fan for the video card or exchange video RAM
1969	  10) install a better fan for the CPU
1970	  11) exchange RAM chips
1971	  12) exchange the motherboard.
1972
1973	  To compile this driver as a module, choose M here: the
1974	  module will be called apm.
1975
1976if APM
1977
1978config APM_IGNORE_USER_SUSPEND
1979	bool "Ignore USER SUSPEND"
1980	---help---
1981	  This option will ignore USER SUSPEND requests. On machines with a
1982	  compliant APM BIOS, you want to say N. However, on the NEC Versa M
1983	  series notebooks, it is necessary to say Y because of a BIOS bug.
1984
1985config APM_DO_ENABLE
1986	bool "Enable PM at boot time"
1987	---help---
1988	  Enable APM features at boot time. From page 36 of the APM BIOS
1989	  specification: "When disabled, the APM BIOS does not automatically
1990	  power manage devices, enter the Standby State, enter the Suspend
1991	  State, or take power saving steps in response to CPU Idle calls."
1992	  This driver will make CPU Idle calls when Linux is idle (unless this
1993	  feature is turned off -- see "Do CPU IDLE calls", below). This
1994	  should always save battery power, but more complicated APM features
1995	  will be dependent on your BIOS implementation. You may need to turn
1996	  this option off if your computer hangs at boot time when using APM
1997	  support, or if it beeps continuously instead of suspending. Turn
1998	  this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1999	  T400CDT. This is off by default since most machines do fine without
2000	  this feature.
2001
2002config APM_CPU_IDLE
2003	depends on CPU_IDLE
2004	bool "Make CPU Idle calls when idle"
2005	---help---
2006	  Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2007	  On some machines, this can activate improved power savings, such as
2008	  a slowed CPU clock rate, when the machine is idle. These idle calls
2009	  are made after the idle loop has run for some length of time (e.g.,
2010	  333 mS). On some machines, this will cause a hang at boot time or
2011	  whenever the CPU becomes idle. (On machines with more than one CPU,
2012	  this option does nothing.)
2013
2014config APM_DISPLAY_BLANK
2015	bool "Enable console blanking using APM"
2016	---help---
2017	  Enable console blanking using the APM. Some laptops can use this to
2018	  turn off the LCD backlight when the screen blanker of the Linux
2019	  virtual console blanks the screen. Note that this is only used by
2020	  the virtual console screen blanker, and won't turn off the backlight
2021	  when using the X Window system. This also doesn't have anything to
2022	  do with your VESA-compliant power-saving monitor. Further, this
2023	  option doesn't work for all laptops -- it might not turn off your
2024	  backlight at all, or it might print a lot of errors to the console,
2025	  especially if you are using gpm.
2026
2027config APM_ALLOW_INTS
2028	bool "Allow interrupts during APM BIOS calls"
2029	---help---
2030	  Normally we disable external interrupts while we are making calls to
2031	  the APM BIOS as a measure to lessen the effects of a badly behaving
2032	  BIOS implementation.  The BIOS should reenable interrupts if it
2033	  needs to.  Unfortunately, some BIOSes do not -- especially those in
2034	  many of the newer IBM Thinkpads.  If you experience hangs when you
2035	  suspend, try setting this to Y.  Otherwise, say N.
2036
2037endif # APM
2038
2039source "drivers/cpufreq/Kconfig"
2040
2041source "drivers/cpuidle/Kconfig"
2042
2043source "drivers/idle/Kconfig"
2044
2045endmenu
2046
2047
2048menu "Bus options (PCI etc.)"
2049
2050config PCI
2051	bool "PCI support"
2052	default y
2053	---help---
2054	  Find out whether you have a PCI motherboard. PCI is the name of a
2055	  bus system, i.e. the way the CPU talks to the other stuff inside
2056	  your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2057	  VESA. If you have PCI, say Y, otherwise N.
2058
2059choice
2060	prompt "PCI access mode"
2061	depends on X86_32 && PCI
2062	default PCI_GOANY
2063	---help---
2064	  On PCI systems, the BIOS can be used to detect the PCI devices and
2065	  determine their configuration. However, some old PCI motherboards
2066	  have BIOS bugs and may crash if this is done. Also, some embedded
2067	  PCI-based systems don't have any BIOS at all. Linux can also try to
2068	  detect the PCI hardware directly without using the BIOS.
2069
2070	  With this option, you can specify how Linux should detect the
2071	  PCI devices. If you choose "BIOS", the BIOS will be used,
2072	  if you choose "Direct", the BIOS won't be used, and if you
2073	  choose "MMConfig", then PCI Express MMCONFIG will be used.
2074	  If you choose "Any", the kernel will try MMCONFIG, then the
2075	  direct access method and falls back to the BIOS if that doesn't
2076	  work. If unsure, go with the default, which is "Any".
2077
2078config PCI_GOBIOS
2079	bool "BIOS"
2080
2081config PCI_GOMMCONFIG
2082	bool "MMConfig"
2083
2084config PCI_GODIRECT
2085	bool "Direct"
2086
2087config PCI_GOOLPC
2088	bool "OLPC XO-1"
2089	depends on OLPC
2090
2091config PCI_GOANY
2092	bool "Any"
2093
2094endchoice
2095
2096config PCI_BIOS
2097	def_bool y
2098	depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2099
2100# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2101config PCI_DIRECT
2102	def_bool y
2103	depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2104
2105config PCI_MMCONFIG
2106	def_bool y
2107	depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2108
2109config PCI_OLPC
2110	def_bool y
2111	depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2112
2113config PCI_XEN
2114	def_bool y
2115	depends on PCI && XEN
2116	select SWIOTLB_XEN
2117
2118config PCI_DOMAINS
2119	def_bool y
2120	depends on PCI
2121
2122config PCI_MMCONFIG
2123	bool "Support mmconfig PCI config space access"
2124	depends on X86_64 && PCI && ACPI
2125
2126config PCI_CNB20LE_QUIRK
2127	bool "Read CNB20LE Host Bridge Windows" if EXPERT
2128	depends on PCI
2129	help
2130	  Read the PCI windows out of the CNB20LE host bridge. This allows
2131	  PCI hotplug to work on systems with the CNB20LE chipset which do
2132	  not have ACPI.
2133
2134	  There's no public spec for this chipset, and this functionality
2135	  is known to be incomplete.
2136
2137	  You should say N unless you know you need this.
2138
2139source "drivers/pci/pcie/Kconfig"
2140
2141source "drivers/pci/Kconfig"
2142
2143# x86_64 have no ISA slots, but can have ISA-style DMA.
2144config ISA_DMA_API
2145	bool "ISA-style DMA support" if (X86_64 && EXPERT)
2146	default y
2147	help
2148	  Enables ISA-style DMA support for devices requiring such controllers.
2149	  If unsure, say Y.
2150
2151if X86_32
2152
2153config ISA
2154	bool "ISA support"
2155	---help---
2156	  Find out whether you have ISA slots on your motherboard.  ISA is the
2157	  name of a bus system, i.e. the way the CPU talks to the other stuff
2158	  inside your box.  Other bus systems are PCI, EISA, MicroChannel
2159	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
2160	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
2161
2162config EISA
2163	bool "EISA support"
2164	depends on ISA
2165	---help---
2166	  The Extended Industry Standard Architecture (EISA) bus was
2167	  developed as an open alternative to the IBM MicroChannel bus.
2168
2169	  The EISA bus provided some of the features of the IBM MicroChannel
2170	  bus while maintaining backward compatibility with cards made for
2171	  the older ISA bus.  The EISA bus saw limited use between 1988 and
2172	  1995 when it was made obsolete by the PCI bus.
2173
2174	  Say Y here if you are building a kernel for an EISA-based machine.
2175
2176	  Otherwise, say N.
2177
2178source "drivers/eisa/Kconfig"
2179
2180config SCx200
2181	tristate "NatSemi SCx200 support"
2182	---help---
2183	  This provides basic support for National Semiconductor's
2184	  (now AMD's) Geode processors.  The driver probes for the
2185	  PCI-IDs of several on-chip devices, so its a good dependency
2186	  for other scx200_* drivers.
2187
2188	  If compiled as a module, the driver is named scx200.
2189
2190config SCx200HR_TIMER
2191	tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2192	depends on SCx200
2193	default y
2194	---help---
2195	  This driver provides a clocksource built upon the on-chip
2196	  27MHz high-resolution timer.  Its also a workaround for
2197	  NSC Geode SC-1100's buggy TSC, which loses time when the
2198	  processor goes idle (as is done by the scheduler).  The
2199	  other workaround is idle=poll boot option.
2200
2201config OLPC
2202	bool "One Laptop Per Child support"
2203	depends on !X86_PAE
2204	select GPIOLIB
2205	select OF
2206	select OF_PROMTREE
2207	select IRQ_DOMAIN
2208	---help---
2209	  Add support for detecting the unique features of the OLPC
2210	  XO hardware.
2211
2212config OLPC_XO1_PM
2213	bool "OLPC XO-1 Power Management"
2214	depends on OLPC && MFD_CS5535 && PM_SLEEP
2215	select MFD_CORE
2216	---help---
2217	  Add support for poweroff and suspend of the OLPC XO-1 laptop.
2218
2219config OLPC_XO1_RTC
2220	bool "OLPC XO-1 Real Time Clock"
2221	depends on OLPC_XO1_PM && RTC_DRV_CMOS
2222	---help---
2223	  Add support for the XO-1 real time clock, which can be used as a
2224	  programmable wakeup source.
2225
2226config OLPC_XO1_SCI
2227	bool "OLPC XO-1 SCI extras"
2228	depends on OLPC && OLPC_XO1_PM
2229	depends on INPUT=y
2230	select POWER_SUPPLY
2231	select GPIO_CS5535
2232	select MFD_CORE
2233	---help---
2234	  Add support for SCI-based features of the OLPC XO-1 laptop:
2235	   - EC-driven system wakeups
2236	   - Power button
2237	   - Ebook switch
2238	   - Lid switch
2239	   - AC adapter status updates
2240	   - Battery status updates
2241
2242config OLPC_XO15_SCI
2243	bool "OLPC XO-1.5 SCI extras"
2244	depends on OLPC && ACPI
2245	select POWER_SUPPLY
2246	---help---
2247	  Add support for SCI-based features of the OLPC XO-1.5 laptop:
2248	   - EC-driven system wakeups
2249	   - AC adapter status updates
2250	   - Battery status updates
2251
2252config ALIX
2253	bool "PCEngines ALIX System Support (LED setup)"
2254	select GPIOLIB
2255	---help---
2256	  This option enables system support for the PCEngines ALIX.
2257	  At present this just sets up LEDs for GPIO control on
2258	  ALIX2/3/6 boards.  However, other system specific setup should
2259	  get added here.
2260
2261	  Note: You must still enable the drivers for GPIO and LED support
2262	  (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2263
2264	  Note: You have to set alix.force=1 for boards with Award BIOS.
2265
2266config NET5501
2267	bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2268	select GPIOLIB
2269	---help---
2270	  This option enables system support for the Soekris Engineering net5501.
2271
2272config GEOS
2273	bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2274	select GPIOLIB
2275	depends on DMI
2276	---help---
2277	  This option enables system support for the Traverse Technologies GEOS.
2278
2279config TS5500
2280	bool "Technologic Systems TS-5500 platform support"
2281	depends on MELAN
2282	select CHECK_SIGNATURE
2283	select NEW_LEDS
2284	select LEDS_CLASS
2285	---help---
2286	  This option enables system support for the Technologic Systems TS-5500.
2287
2288endif # X86_32
2289
2290config AMD_NB
2291	def_bool y
2292	depends on CPU_SUP_AMD && PCI
2293
2294source "drivers/pcmcia/Kconfig"
2295
2296source "drivers/pci/hotplug/Kconfig"
2297
2298config RAPIDIO
2299	tristate "RapidIO support"
2300	depends on PCI
2301	default n
2302	help
2303	  If enabled this option will include drivers and the core
2304	  infrastructure code to support RapidIO interconnect devices.
2305
2306source "drivers/rapidio/Kconfig"
2307
2308config X86_SYSFB
2309	bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2310	help
2311	  Firmwares often provide initial graphics framebuffers so the BIOS,
2312	  bootloader or kernel can show basic video-output during boot for
2313	  user-guidance and debugging. Historically, x86 used the VESA BIOS
2314	  Extensions and EFI-framebuffers for this, which are mostly limited
2315	  to x86.
2316	  This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2317	  framebuffers so the new generic system-framebuffer drivers can be
2318	  used on x86. If the framebuffer is not compatible with the generic
2319	  modes, it is adverticed as fallback platform framebuffer so legacy
2320	  drivers like efifb, vesafb and uvesafb can pick it up.
2321	  If this option is not selected, all system framebuffers are always
2322	  marked as fallback platform framebuffers as usual.
2323
2324	  Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2325	  not be able to pick up generic system framebuffers if this option
2326	  is selected. You are highly encouraged to enable simplefb as
2327	  replacement if you select this option. simplefb can correctly deal
2328	  with generic system framebuffers. But you should still keep vesafb
2329	  and others enabled as fallback if a system framebuffer is
2330	  incompatible with simplefb.
2331
2332	  If unsure, say Y.
2333
2334endmenu
2335
2336
2337menu "Executable file formats / Emulations"
2338
2339source "fs/Kconfig.binfmt"
2340
2341config IA32_EMULATION
2342	bool "IA32 Emulation"
2343	depends on X86_64
2344	select BINFMT_ELF
2345	select COMPAT_BINFMT_ELF
2346	select HAVE_UID16
2347	---help---
2348	  Include code to run legacy 32-bit programs under a
2349	  64-bit kernel. You should likely turn this on, unless you're
2350	  100% sure that you don't have any 32-bit programs left.
2351
2352config IA32_AOUT
2353	tristate "IA32 a.out support"
2354	depends on IA32_EMULATION
2355	---help---
2356	  Support old a.out binaries in the 32bit emulation.
2357
2358config X86_X32
2359	bool "x32 ABI for 64-bit mode"
2360	depends on X86_64 && IA32_EMULATION
2361	---help---
2362	  Include code to run binaries for the x32 native 32-bit ABI
2363	  for 64-bit processors.  An x32 process gets access to the
2364	  full 64-bit register file and wide data path while leaving
2365	  pointers at 32 bits for smaller memory footprint.
2366
2367	  You will need a recent binutils (2.22 or later) with
2368	  elf32_x86_64 support enabled to compile a kernel with this
2369	  option set.
2370
2371config COMPAT
2372	def_bool y
2373	depends on IA32_EMULATION || X86_X32
2374	select ARCH_WANT_OLD_COMPAT_IPC
2375
2376if COMPAT
2377config COMPAT_FOR_U64_ALIGNMENT
2378	def_bool y
2379
2380config SYSVIPC_COMPAT
2381	def_bool y
2382	depends on SYSVIPC
2383
2384config KEYS_COMPAT
2385	def_bool y
2386	depends on KEYS
2387endif
2388
2389endmenu
2390
2391
2392config HAVE_ATOMIC_IOMAP
2393	def_bool y
2394	depends on X86_32
2395
2396config X86_DEV_DMA_OPS
2397	bool
2398	depends on X86_64 || STA2X11
2399
2400config X86_DMA_REMAP
2401	bool
2402	depends on STA2X11
2403
2404config IOSF_MBI
2405	tristate
2406	default m
2407	depends on PCI
2408
2409config PMC_ATOM
2410	def_bool y
2411        depends on PCI
2412
2413source "net/Kconfig"
2414
2415source "drivers/Kconfig"
2416
2417source "drivers/firmware/Kconfig"
2418
2419source "fs/Kconfig"
2420
2421source "arch/x86/Kconfig.debug"
2422
2423source "security/Kconfig"
2424
2425source "crypto/Kconfig"
2426
2427source "arch/x86/kvm/Kconfig"
2428
2429source "lib/Kconfig"
2430