xref: /openbmc/linux/arch/x86/Kconfig (revision f7018c21)
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
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 if !SWIOTLB
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_FUNCTION_TRACE_MCOUNT_TEST
58	select HAVE_SYSCALL_TRACEPOINTS
59	select SYSCTL_EXCEPTION_TRACE
60	select HAVE_KVM
61	select HAVE_ARCH_KGDB
62	select HAVE_ARCH_TRACEHOOK
63	select HAVE_GENERIC_DMA_COHERENT if X86_32
64	select HAVE_EFFICIENT_UNALIGNED_ACCESS
65	select USER_STACKTRACE_SUPPORT
66	select HAVE_REGS_AND_STACK_ACCESS_API
67	select HAVE_DMA_API_DEBUG
68	select HAVE_KERNEL_GZIP
69	select HAVE_KERNEL_BZIP2
70	select HAVE_KERNEL_LZMA
71	select HAVE_KERNEL_XZ
72	select HAVE_KERNEL_LZO
73	select HAVE_KERNEL_LZ4
74	select HAVE_HW_BREAKPOINT
75	select HAVE_MIXED_BREAKPOINTS_REGS
76	select PERF_EVENTS
77	select HAVE_PERF_EVENTS_NMI
78	select HAVE_PERF_REGS
79	select HAVE_PERF_USER_STACK_DUMP
80	select HAVE_DEBUG_KMEMLEAK
81	select ANON_INODES
82	select HAVE_ALIGNED_STRUCT_PAGE if SLUB
83	select HAVE_CMPXCHG_LOCAL
84	select HAVE_CMPXCHG_DOUBLE
85	select HAVE_ARCH_KMEMCHECK
86	select HAVE_USER_RETURN_NOTIFIER
87	select ARCH_BINFMT_ELF_RANDOMIZE_PIE
88	select HAVE_ARCH_JUMP_LABEL
89	select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
90	select SPARSE_IRQ
91	select GENERIC_FIND_FIRST_BIT
92	select GENERIC_IRQ_PROBE
93	select GENERIC_PENDING_IRQ if SMP
94	select GENERIC_IRQ_SHOW
95	select GENERIC_CLOCKEVENTS_MIN_ADJUST
96	select IRQ_FORCED_THREADING
97	select HAVE_BPF_JIT if X86_64
98	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
99	select CLKEVT_I8253
100	select ARCH_HAVE_NMI_SAFE_CMPXCHG
101	select GENERIC_IOMAP
102	select DCACHE_WORD_ACCESS
103	select GENERIC_SMP_IDLE_THREAD
104	select ARCH_WANT_IPC_PARSE_VERSION if X86_32
105	select HAVE_ARCH_SECCOMP_FILTER
106	select BUILDTIME_EXTABLE_SORT
107	select GENERIC_CMOS_UPDATE
108	select HAVE_ARCH_SOFT_DIRTY
109	select CLOCKSOURCE_WATCHDOG
110	select GENERIC_CLOCKEVENTS
111	select ARCH_CLOCKSOURCE_DATA
112	select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
113	select GENERIC_TIME_VSYSCALL
114	select KTIME_SCALAR if X86_32
115	select GENERIC_STRNCPY_FROM_USER
116	select GENERIC_STRNLEN_USER
117	select HAVE_CONTEXT_TRACKING if X86_64
118	select HAVE_IRQ_TIME_ACCOUNTING
119	select VIRT_TO_BUS
120	select MODULES_USE_ELF_REL if X86_32
121	select MODULES_USE_ELF_RELA if X86_64
122	select CLONE_BACKWARDS if X86_32
123	select ARCH_USE_BUILTIN_BSWAP
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
134config INSTRUCTION_DECODER
135	def_bool y
136	depends on KPROBES || PERF_EVENTS || UPROBES
137
138config OUTPUT_FORMAT
139	string
140	default "elf32-i386" if X86_32
141	default "elf64-x86-64" if X86_64
142
143config ARCH_DEFCONFIG
144	string
145	default "arch/x86/configs/i386_defconfig" if X86_32
146	default "arch/x86/configs/x86_64_defconfig" if X86_64
147
148config LOCKDEP_SUPPORT
149	def_bool y
150
151config STACKTRACE_SUPPORT
152	def_bool y
153
154config HAVE_LATENCYTOP_SUPPORT
155	def_bool y
156
157config MMU
158	def_bool y
159
160config SBUS
161	bool
162
163config NEED_DMA_MAP_STATE
164	def_bool y
165	depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG
166
167config NEED_SG_DMA_LENGTH
168	def_bool y
169
170config GENERIC_ISA_DMA
171	def_bool y
172	depends on ISA_DMA_API
173
174config GENERIC_BUG
175	def_bool y
176	depends on BUG
177	select GENERIC_BUG_RELATIVE_POINTERS if X86_64
178
179config GENERIC_BUG_RELATIVE_POINTERS
180	bool
181
182config GENERIC_HWEIGHT
183	def_bool y
184
185config ARCH_MAY_HAVE_PC_FDC
186	def_bool y
187	depends on ISA_DMA_API
188
189config RWSEM_XCHGADD_ALGORITHM
190	def_bool y
191
192config GENERIC_CALIBRATE_DELAY
193	def_bool y
194
195config ARCH_HAS_CPU_RELAX
196	def_bool y
197
198config ARCH_HAS_CACHE_LINE_SIZE
199	def_bool y
200
201config HAVE_SETUP_PER_CPU_AREA
202	def_bool y
203
204config NEED_PER_CPU_EMBED_FIRST_CHUNK
205	def_bool y
206
207config NEED_PER_CPU_PAGE_FIRST_CHUNK
208	def_bool y
209
210config ARCH_HIBERNATION_POSSIBLE
211	def_bool y
212
213config ARCH_SUSPEND_POSSIBLE
214	def_bool y
215
216config ARCH_WANT_HUGE_PMD_SHARE
217	def_bool y
218
219config ARCH_WANT_GENERAL_HUGETLB
220	def_bool y
221
222config ZONE_DMA32
223	bool
224	default X86_64
225
226config AUDIT_ARCH
227	bool
228	default X86_64
229
230config ARCH_SUPPORTS_OPTIMIZED_INLINING
231	def_bool y
232
233config ARCH_SUPPORTS_DEBUG_PAGEALLOC
234	def_bool y
235
236config HAVE_INTEL_TXT
237	def_bool y
238	depends on INTEL_IOMMU && ACPI
239
240config X86_32_SMP
241	def_bool y
242	depends on X86_32 && SMP
243
244config X86_64_SMP
245	def_bool y
246	depends on X86_64 && SMP
247
248config X86_HT
249	def_bool y
250	depends on SMP
251
252config X86_32_LAZY_GS
253	def_bool y
254	depends on X86_32 && !CC_STACKPROTECTOR
255
256config ARCH_HWEIGHT_CFLAGS
257	string
258	default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
259	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
260
261config ARCH_SUPPORTS_UPROBES
262	def_bool y
263
264source "init/Kconfig"
265source "kernel/Kconfig.freezer"
266
267menu "Processor type and features"
268
269config ZONE_DMA
270	bool "DMA memory allocation support" if EXPERT
271	default y
272	help
273	  DMA memory allocation support allows devices with less than 32-bit
274	  addressing to allocate within the first 16MB of address space.
275	  Disable if no such devices will be used.
276
277	  If unsure, say Y.
278
279config SMP
280	bool "Symmetric multi-processing support"
281	---help---
282	  This enables support for systems with more than one CPU. If you have
283	  a system with only one CPU, say N. If you have a system with more
284	  than one CPU, say Y.
285
286	  If you say N here, the kernel will run on uni- and multiprocessor
287	  machines, but will use only one CPU of a multiprocessor machine. If
288	  you say Y here, the kernel will run on many, but not all,
289	  uniprocessor machines. On a uniprocessor machine, the kernel
290	  will run faster if you say N here.
291
292	  Note that if you say Y here and choose architecture "586" or
293	  "Pentium" under "Processor family", the kernel will not work on 486
294	  architectures. Similarly, multiprocessor kernels for the "PPro"
295	  architecture may not work on all Pentium based boards.
296
297	  People using multiprocessor machines who say Y here should also say
298	  Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
299	  Management" code will be disabled if you say Y here.
300
301	  See also <file:Documentation/x86/i386/IO-APIC.txt>,
302	  <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
303	  <http://www.tldp.org/docs.html#howto>.
304
305	  If you don't know what to do here, say N.
306
307config X86_X2APIC
308	bool "Support x2apic"
309	depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
310	---help---
311	  This enables x2apic support on CPUs that have this feature.
312
313	  This allows 32-bit apic IDs (so it can support very large systems),
314	  and accesses the local apic via MSRs not via mmio.
315
316	  If you don't know what to do here, say N.
317
318config X86_MPPARSE
319	bool "Enable MPS table" if ACPI || SFI
320	default y
321	depends on X86_LOCAL_APIC
322	---help---
323	  For old smp systems that do not have proper acpi support. Newer systems
324	  (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
325
326config X86_BIGSMP
327	bool "Support for big SMP systems with more than 8 CPUs"
328	depends on X86_32 && SMP
329	---help---
330	  This option is needed for the systems that have more than 8 CPUs
331
332config GOLDFISH
333       def_bool y
334       depends on X86_GOLDFISH
335
336if X86_32
337config X86_EXTENDED_PLATFORM
338	bool "Support for extended (non-PC) x86 platforms"
339	default y
340	---help---
341	  If you disable this option then the kernel will only support
342	  standard PC platforms. (which covers the vast majority of
343	  systems out there.)
344
345	  If you enable this option then you'll be able to select support
346	  for the following (non-PC) 32 bit x86 platforms:
347		Goldfish (Android emulator)
348		AMD Elan
349		RDC R-321x SoC
350		SGI 320/540 (Visual Workstation)
351		STA2X11-based (e.g. Northville)
352		Moorestown MID devices
353
354	  If you have one of these systems, or if you want to build a
355	  generic distribution kernel, say Y here - otherwise say N.
356endif
357
358if X86_64
359config X86_EXTENDED_PLATFORM
360	bool "Support for extended (non-PC) x86 platforms"
361	default y
362	---help---
363	  If you disable this option then the kernel will only support
364	  standard PC platforms. (which covers the vast majority of
365	  systems out there.)
366
367	  If you enable this option then you'll be able to select support
368	  for the following (non-PC) 64 bit x86 platforms:
369		Numascale NumaChip
370		ScaleMP vSMP
371		SGI Ultraviolet
372
373	  If you have one of these systems, or if you want to build a
374	  generic distribution kernel, say Y here - otherwise say N.
375endif
376# This is an alphabetically sorted list of 64 bit extended platforms
377# Please maintain the alphabetic order if and when there are additions
378config X86_NUMACHIP
379	bool "Numascale NumaChip"
380	depends on X86_64
381	depends on X86_EXTENDED_PLATFORM
382	depends on NUMA
383	depends on SMP
384	depends on X86_X2APIC
385	depends on PCI_MMCONFIG
386	---help---
387	  Adds support for Numascale NumaChip large-SMP systems. Needed to
388	  enable more than ~168 cores.
389	  If you don't have one of these, you should say N here.
390
391config X86_VSMP
392	bool "ScaleMP vSMP"
393	select HYPERVISOR_GUEST
394	select PARAVIRT
395	depends on X86_64 && PCI
396	depends on X86_EXTENDED_PLATFORM
397	depends on SMP
398	---help---
399	  Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
400	  supposed to run on these EM64T-based machines.  Only choose this option
401	  if you have one of these machines.
402
403config X86_UV
404	bool "SGI Ultraviolet"
405	depends on X86_64
406	depends on X86_EXTENDED_PLATFORM
407	depends on NUMA
408	depends on X86_X2APIC
409	---help---
410	  This option is needed in order to support SGI Ultraviolet systems.
411	  If you don't have one of these, you should say N here.
412
413# Following is an alphabetically sorted list of 32 bit extended platforms
414# Please maintain the alphabetic order if and when there are additions
415
416config X86_GOLDFISH
417       bool "Goldfish (Virtual Platform)"
418       depends on X86_32
419       depends on X86_EXTENDED_PLATFORM
420       ---help---
421	 Enable support for the Goldfish virtual platform used primarily
422	 for Android development. Unless you are building for the Android
423	 Goldfish emulator say N here.
424
425config X86_INTEL_CE
426	bool "CE4100 TV platform"
427	depends on PCI
428	depends on PCI_GODIRECT
429	depends on X86_32
430	depends on X86_EXTENDED_PLATFORM
431	select X86_REBOOTFIXUPS
432	select OF
433	select OF_EARLY_FLATTREE
434	select IRQ_DOMAIN
435	---help---
436	  Select for the Intel CE media processor (CE4100) SOC.
437	  This option compiles in support for the CE4100 SOC for settop
438	  boxes and media devices.
439
440config X86_INTEL_MID
441	bool "Intel MID platform support"
442	depends on X86_32
443	depends on X86_EXTENDED_PLATFORM
444	depends on X86_PLATFORM_DEVICES
445	depends on PCI
446	depends on PCI_GOANY
447	depends on X86_IO_APIC
448	select SFI
449	select I2C
450	select DW_APB_TIMER
451	select APB_TIMER
452	select INTEL_SCU_IPC
453	select MFD_INTEL_MSIC
454	---help---
455	  Select to build a kernel capable of supporting Intel MID (Mobile
456	  Internet Device) platform systems which do not have the PCI legacy
457	  interfaces. If you are building for a PC class system say N here.
458
459	  Intel MID platforms are based on an Intel processor and chipset which
460	  consume less power than most of the x86 derivatives.
461
462config X86_INTEL_LPSS
463	bool "Intel Low Power Subsystem Support"
464	depends on ACPI
465	select COMMON_CLK
466	select PINCTRL
467	---help---
468	  Select to build support for Intel Low Power Subsystem such as
469	  found on Intel Lynxpoint PCH. Selecting this option enables
470	  things like clock tree (common clock framework) and pincontrol
471	  which are needed by the LPSS peripheral drivers.
472
473config X86_RDC321X
474	bool "RDC R-321x SoC"
475	depends on X86_32
476	depends on X86_EXTENDED_PLATFORM
477	select M486
478	select X86_REBOOTFIXUPS
479	---help---
480	  This option is needed for RDC R-321x system-on-chip, also known
481	  as R-8610-(G).
482	  If you don't have one of these chips, you should say N here.
483
484config X86_32_NON_STANDARD
485	bool "Support non-standard 32-bit SMP architectures"
486	depends on X86_32 && SMP
487	depends on X86_EXTENDED_PLATFORM
488	---help---
489	  This option compiles in the bigsmp and STA2X11 default
490	  subarchitectures.  It is intended for a generic binary
491	  kernel. If you select them all, kernel will probe it one by
492	  one and will fallback to default.
493
494# Alphabetically sorted list of Non standard 32 bit platforms
495
496config X86_SUPPORTS_MEMORY_FAILURE
497	def_bool y
498	# MCE code calls memory_failure():
499	depends on X86_MCE
500	# On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
501	# On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
502	depends on X86_64 || !SPARSEMEM
503	select ARCH_SUPPORTS_MEMORY_FAILURE
504
505config STA2X11
506	bool "STA2X11 Companion Chip Support"
507	depends on X86_32_NON_STANDARD && PCI
508	select X86_DEV_DMA_OPS
509	select X86_DMA_REMAP
510	select SWIOTLB
511	select MFD_STA2X11
512	select ARCH_REQUIRE_GPIOLIB
513	default n
514	---help---
515	  This adds support for boards based on the STA2X11 IO-Hub,
516	  a.k.a. "ConneXt". The chip is used in place of the standard
517	  PC chipset, so all "standard" peripherals are missing. If this
518	  option is selected the kernel will still be able to boot on
519	  standard PC machines.
520
521config X86_32_IRIS
522	tristate "Eurobraille/Iris poweroff module"
523	depends on X86_32
524	---help---
525	  The Iris machines from EuroBraille do not have APM or ACPI support
526	  to shut themselves down properly.  A special I/O sequence is
527	  needed to do so, which is what this module does at
528	  kernel shutdown.
529
530	  This is only for Iris machines from EuroBraille.
531
532	  If unused, say N.
533
534config SCHED_OMIT_FRAME_POINTER
535	def_bool y
536	prompt "Single-depth WCHAN output"
537	depends on X86
538	---help---
539	  Calculate simpler /proc/<PID>/wchan values. If this option
540	  is disabled then wchan values will recurse back to the
541	  caller function. This provides more accurate wchan values,
542	  at the expense of slightly more scheduling overhead.
543
544	  If in doubt, say "Y".
545
546menuconfig HYPERVISOR_GUEST
547	bool "Linux guest support"
548	---help---
549	  Say Y here to enable options for running Linux under various hyper-
550	  visors. This option enables basic hypervisor detection and platform
551	  setup.
552
553	  If you say N, all options in this submenu will be skipped and
554	  disabled, and Linux guest support won't be built in.
555
556if HYPERVISOR_GUEST
557
558config PARAVIRT
559	bool "Enable paravirtualization code"
560	---help---
561	  This changes the kernel so it can modify itself when it is run
562	  under a hypervisor, potentially improving performance significantly
563	  over full virtualization.  However, when run without a hypervisor
564	  the kernel is theoretically slower and slightly larger.
565
566config PARAVIRT_DEBUG
567	bool "paravirt-ops debugging"
568	depends on PARAVIRT && DEBUG_KERNEL
569	---help---
570	  Enable to debug paravirt_ops internals.  Specifically, BUG if
571	  a paravirt_op is missing when it is called.
572
573config PARAVIRT_SPINLOCKS
574	bool "Paravirtualization layer for spinlocks"
575	depends on PARAVIRT && SMP
576	select UNINLINE_SPIN_UNLOCK
577	---help---
578	  Paravirtualized spinlocks allow a pvops backend to replace the
579	  spinlock implementation with something virtualization-friendly
580	  (for example, block the virtual CPU rather than spinning).
581
582	  It has a minimal impact on native kernels and gives a nice performance
583	  benefit on paravirtualized KVM / Xen kernels.
584
585	  If you are unsure how to answer this question, answer Y.
586
587source "arch/x86/xen/Kconfig"
588
589config KVM_GUEST
590	bool "KVM Guest support (including kvmclock)"
591	depends on PARAVIRT
592	select PARAVIRT_CLOCK
593	default y
594	---help---
595	  This option enables various optimizations for running under the KVM
596	  hypervisor. It includes a paravirtualized clock, so that instead
597	  of relying on a PIT (or probably other) emulation by the
598	  underlying device model, the host provides the guest with
599	  timing infrastructure such as time of day, and system time
600
601config KVM_DEBUG_FS
602	bool "Enable debug information for KVM Guests in debugfs"
603	depends on KVM_GUEST && DEBUG_FS
604	default n
605	---help---
606	  This option enables collection of various statistics for KVM guest.
607	  Statistics are displayed in debugfs filesystem. Enabling this option
608	  may incur significant overhead.
609
610source "arch/x86/lguest/Kconfig"
611
612config PARAVIRT_TIME_ACCOUNTING
613	bool "Paravirtual steal time accounting"
614	depends on PARAVIRT
615	default n
616	---help---
617	  Select this option to enable fine granularity task steal time
618	  accounting. Time spent executing other tasks in parallel with
619	  the current vCPU is discounted from the vCPU power. To account for
620	  that, there can be a small performance impact.
621
622	  If in doubt, say N here.
623
624config PARAVIRT_CLOCK
625	bool
626
627endif #HYPERVISOR_GUEST
628
629config NO_BOOTMEM
630	def_bool y
631
632config MEMTEST
633	bool "Memtest"
634	---help---
635	  This option adds a kernel parameter 'memtest', which allows memtest
636	  to be set.
637	        memtest=0, mean disabled; -- default
638	        memtest=1, mean do 1 test pattern;
639	        ...
640	        memtest=4, mean do 4 test patterns.
641	  If you are unsure how to answer this question, answer N.
642
643source "arch/x86/Kconfig.cpu"
644
645config HPET_TIMER
646	def_bool X86_64
647	prompt "HPET Timer Support" if X86_32
648	---help---
649	  Use the IA-PC HPET (High Precision Event Timer) to manage
650	  time in preference to the PIT and RTC, if a HPET is
651	  present.
652	  HPET is the next generation timer replacing legacy 8254s.
653	  The HPET provides a stable time base on SMP
654	  systems, unlike the TSC, but it is more expensive to access,
655	  as it is off-chip.  You can find the HPET spec at
656	  <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
657
658	  You can safely choose Y here.  However, HPET will only be
659	  activated if the platform and the BIOS support this feature.
660	  Otherwise the 8254 will be used for timing services.
661
662	  Choose N to continue using the legacy 8254 timer.
663
664config HPET_EMULATE_RTC
665	def_bool y
666	depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
667
668config APB_TIMER
669       def_bool y if X86_INTEL_MID
670       prompt "Intel MID APB Timer Support" if X86_INTEL_MID
671       select DW_APB_TIMER
672       depends on X86_INTEL_MID && SFI
673       help
674         APB timer is the replacement for 8254, HPET on X86 MID platforms.
675         The APBT provides a stable time base on SMP
676         systems, unlike the TSC, but it is more expensive to access,
677         as it is off-chip. APB timers are always running regardless of CPU
678         C states, they are used as per CPU clockevent device when possible.
679
680# Mark as expert because too many people got it wrong.
681# The code disables itself when not needed.
682config DMI
683	default y
684	select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
685	bool "Enable DMI scanning" if EXPERT
686	---help---
687	  Enabled scanning of DMI to identify machine quirks. Say Y
688	  here unless you have verified that your setup is not
689	  affected by entries in the DMI blacklist. Required by PNP
690	  BIOS code.
691
692config GART_IOMMU
693	bool "Old AMD GART IOMMU support"
694	select SWIOTLB
695	depends on X86_64 && PCI && AMD_NB
696	---help---
697	  Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
698	  GART based hardware IOMMUs.
699
700	  The GART supports full DMA access for devices with 32-bit access
701	  limitations, on systems with more than 3 GB. This is usually needed
702	  for USB, sound, many IDE/SATA chipsets and some other devices.
703
704	  Newer systems typically have a modern AMD IOMMU, supported via
705	  the CONFIG_AMD_IOMMU=y config option.
706
707	  In normal configurations this driver is only active when needed:
708	  there's more than 3 GB of memory and the system contains a
709	  32-bit limited device.
710
711	  If unsure, say Y.
712
713config CALGARY_IOMMU
714	bool "IBM Calgary IOMMU support"
715	select SWIOTLB
716	depends on X86_64 && PCI
717	---help---
718	  Support for hardware IOMMUs in IBM's xSeries x366 and x460
719	  systems. Needed to run systems with more than 3GB of memory
720	  properly with 32-bit PCI devices that do not support DAC
721	  (Double Address Cycle). Calgary also supports bus level
722	  isolation, where all DMAs pass through the IOMMU.  This
723	  prevents them from going anywhere except their intended
724	  destination. This catches hard-to-find kernel bugs and
725	  mis-behaving drivers and devices that do not use the DMA-API
726	  properly to set up their DMA buffers.  The IOMMU can be
727	  turned off at boot time with the iommu=off parameter.
728	  Normally the kernel will make the right choice by itself.
729	  If unsure, say Y.
730
731config CALGARY_IOMMU_ENABLED_BY_DEFAULT
732	def_bool y
733	prompt "Should Calgary be enabled by default?"
734	depends on CALGARY_IOMMU
735	---help---
736	  Should Calgary be enabled by default? if you choose 'y', Calgary
737	  will be used (if it exists). If you choose 'n', Calgary will not be
738	  used even if it exists. If you choose 'n' and would like to use
739	  Calgary anyway, pass 'iommu=calgary' on the kernel command line.
740	  If unsure, say Y.
741
742# need this always selected by IOMMU for the VIA workaround
743config SWIOTLB
744	def_bool y if X86_64
745	---help---
746	  Support for software bounce buffers used on x86-64 systems
747	  which don't have a hardware IOMMU. Using this PCI devices
748	  which can only access 32-bits of memory can be used on systems
749	  with more than 3 GB of memory.
750	  If unsure, say Y.
751
752config IOMMU_HELPER
753	def_bool y
754	depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
755
756config MAXSMP
757	bool "Enable Maximum number of SMP Processors and NUMA Nodes"
758	depends on X86_64 && SMP && DEBUG_KERNEL
759	select CPUMASK_OFFSTACK
760	---help---
761	  Enable maximum number of CPUS and NUMA Nodes for this architecture.
762	  If unsure, say N.
763
764config NR_CPUS
765	int "Maximum number of CPUs" if SMP && !MAXSMP
766	range 2 8 if SMP && X86_32 && !X86_BIGSMP
767	range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
768	range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
769	default "1" if !SMP
770	default "8192" if MAXSMP
771	default "32" if SMP && X86_BIGSMP
772	default "8" if SMP
773	---help---
774	  This allows you to specify the maximum number of CPUs which this
775	  kernel will support.  If CPUMASK_OFFSTACK is enabled, the maximum
776	  supported value is 4096, otherwise the maximum value is 512.  The
777	  minimum value which makes sense is 2.
778
779	  This is purely to save memory - each supported CPU adds
780	  approximately eight kilobytes to the kernel image.
781
782config SCHED_SMT
783	bool "SMT (Hyperthreading) scheduler support"
784	depends on X86_HT
785	---help---
786	  SMT scheduler support improves the CPU scheduler's decision making
787	  when dealing with Intel Pentium 4 chips with HyperThreading at a
788	  cost of slightly increased overhead in some places. If unsure say
789	  N here.
790
791config SCHED_MC
792	def_bool y
793	prompt "Multi-core scheduler support"
794	depends on X86_HT
795	---help---
796	  Multi-core scheduler support improves the CPU scheduler's decision
797	  making when dealing with multi-core CPU chips at a cost of slightly
798	  increased overhead in some places. If unsure say N here.
799
800source "kernel/Kconfig.preempt"
801
802config X86_UP_APIC
803	bool "Local APIC support on uniprocessors"
804	depends on X86_32 && !SMP && !X86_32_NON_STANDARD && !PCI_MSI
805	---help---
806	  A local APIC (Advanced Programmable Interrupt Controller) is an
807	  integrated interrupt controller in the CPU. If you have a single-CPU
808	  system which has a processor with a local APIC, you can say Y here to
809	  enable and use it. If you say Y here even though your machine doesn't
810	  have a local APIC, then the kernel will still run with no slowdown at
811	  all. The local APIC supports CPU-generated self-interrupts (timer,
812	  performance counters), and the NMI watchdog which detects hard
813	  lockups.
814
815config X86_UP_IOAPIC
816	bool "IO-APIC support on uniprocessors"
817	depends on X86_UP_APIC
818	---help---
819	  An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
820	  SMP-capable replacement for PC-style interrupt controllers. Most
821	  SMP systems and many recent uniprocessor systems have one.
822
823	  If you have a single-CPU system with an IO-APIC, you can say Y here
824	  to use it. If you say Y here even though your machine doesn't have
825	  an IO-APIC, then the kernel will still run with no slowdown at all.
826
827config X86_LOCAL_APIC
828	def_bool y
829	depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
830
831config X86_IO_APIC
832	def_bool y
833	depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC || PCI_MSI
834
835config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
836	bool "Reroute for broken boot IRQs"
837	depends on X86_IO_APIC
838	---help---
839	  This option enables a workaround that fixes a source of
840	  spurious interrupts. This is recommended when threaded
841	  interrupt handling is used on systems where the generation of
842	  superfluous "boot interrupts" cannot be disabled.
843
844	  Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
845	  entry in the chipset's IO-APIC is masked (as, e.g. the RT
846	  kernel does during interrupt handling). On chipsets where this
847	  boot IRQ generation cannot be disabled, this workaround keeps
848	  the original IRQ line masked so that only the equivalent "boot
849	  IRQ" is delivered to the CPUs. The workaround also tells the
850	  kernel to set up the IRQ handler on the boot IRQ line. In this
851	  way only one interrupt is delivered to the kernel. Otherwise
852	  the spurious second interrupt may cause the kernel to bring
853	  down (vital) interrupt lines.
854
855	  Only affects "broken" chipsets. Interrupt sharing may be
856	  increased on these systems.
857
858config X86_MCE
859	bool "Machine Check / overheating reporting"
860	default y
861	---help---
862	  Machine Check support allows the processor to notify the
863	  kernel if it detects a problem (e.g. overheating, data corruption).
864	  The action the kernel takes depends on the severity of the problem,
865	  ranging from warning messages to halting the machine.
866
867config X86_MCE_INTEL
868	def_bool y
869	prompt "Intel MCE features"
870	depends on X86_MCE && X86_LOCAL_APIC
871	---help---
872	   Additional support for intel specific MCE features such as
873	   the thermal monitor.
874
875config X86_MCE_AMD
876	def_bool y
877	prompt "AMD MCE features"
878	depends on X86_MCE && X86_LOCAL_APIC
879	---help---
880	   Additional support for AMD specific MCE features such as
881	   the DRAM Error Threshold.
882
883config X86_ANCIENT_MCE
884	bool "Support for old Pentium 5 / WinChip machine checks"
885	depends on X86_32 && X86_MCE
886	---help---
887	  Include support for machine check handling on old Pentium 5 or WinChip
888	  systems. These typically need to be enabled explicitly on the command
889	  line.
890
891config X86_MCE_THRESHOLD
892	depends on X86_MCE_AMD || X86_MCE_INTEL
893	def_bool y
894
895config X86_MCE_INJECT
896	depends on X86_MCE
897	tristate "Machine check injector support"
898	---help---
899	  Provide support for injecting machine checks for testing purposes.
900	  If you don't know what a machine check is and you don't do kernel
901	  QA it is safe to say n.
902
903config X86_THERMAL_VECTOR
904	def_bool y
905	depends on X86_MCE_INTEL
906
907config VM86
908	bool "Enable VM86 support" if EXPERT
909	default y
910	depends on X86_32
911	---help---
912	  This option is required by programs like DOSEMU to run 16-bit legacy
913	  code on X86 processors. It also may be needed by software like
914	  XFree86 to initialize some video cards via BIOS. Disabling this
915	  option saves about 6k.
916
917config TOSHIBA
918	tristate "Toshiba Laptop support"
919	depends on X86_32
920	---help---
921	  This adds a driver to safely access the System Management Mode of
922	  the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
923	  not work on models with a Phoenix BIOS. The System Management Mode
924	  is used to set the BIOS and power saving options on Toshiba portables.
925
926	  For information on utilities to make use of this driver see the
927	  Toshiba Linux utilities web site at:
928	  <http://www.buzzard.org.uk/toshiba/>.
929
930	  Say Y if you intend to run this kernel on a Toshiba portable.
931	  Say N otherwise.
932
933config I8K
934	tristate "Dell laptop support"
935	select HWMON
936	---help---
937	  This adds a driver to safely access the System Management Mode
938	  of the CPU on the Dell Inspiron 8000. The System Management Mode
939	  is used to read cpu temperature and cooling fan status and to
940	  control the fans on the I8K portables.
941
942	  This driver has been tested only on the Inspiron 8000 but it may
943	  also work with other Dell laptops. You can force loading on other
944	  models by passing the parameter `force=1' to the module. Use at
945	  your own risk.
946
947	  For information on utilities to make use of this driver see the
948	  I8K Linux utilities web site at:
949	  <http://people.debian.org/~dz/i8k/>
950
951	  Say Y if you intend to run this kernel on a Dell Inspiron 8000.
952	  Say N otherwise.
953
954config X86_REBOOTFIXUPS
955	bool "Enable X86 board specific fixups for reboot"
956	depends on X86_32
957	---help---
958	  This enables chipset and/or board specific fixups to be done
959	  in order to get reboot to work correctly. This is only needed on
960	  some combinations of hardware and BIOS. The symptom, for which
961	  this config is intended, is when reboot ends with a stalled/hung
962	  system.
963
964	  Currently, the only fixup is for the Geode machines using
965	  CS5530A and CS5536 chipsets and the RDC R-321x SoC.
966
967	  Say Y if you want to enable the fixup. Currently, it's safe to
968	  enable this option even if you don't need it.
969	  Say N otherwise.
970
971config MICROCODE
972	tristate "CPU microcode loading support"
973	depends on CPU_SUP_AMD || CPU_SUP_INTEL
974	select FW_LOADER
975	---help---
976
977	  If you say Y here, you will be able to update the microcode on
978	  certain Intel and AMD processors. The Intel support is for the
979	  IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
980	  Xeon etc. The AMD support is for families 0x10 and later. You will
981	  obviously need the actual microcode binary data itself which is not
982	  shipped with the Linux kernel.
983
984	  This option selects the general module only, you need to select
985	  at least one vendor specific module as well.
986
987	  To compile this driver as a module, choose M here: the module
988	  will be called microcode.
989
990config MICROCODE_INTEL
991	bool "Intel microcode loading support"
992	depends on MICROCODE
993	default MICROCODE
994	select FW_LOADER
995	---help---
996	  This options enables microcode patch loading support for Intel
997	  processors.
998
999	  For the current Intel microcode data package go to
1000	  <https://downloadcenter.intel.com> and search for
1001	  'Linux Processor Microcode Data File'.
1002
1003config MICROCODE_AMD
1004	bool "AMD microcode loading support"
1005	depends on MICROCODE
1006	select FW_LOADER
1007	---help---
1008	  If you select this option, microcode patch loading support for AMD
1009	  processors will be enabled.
1010
1011config MICROCODE_OLD_INTERFACE
1012	def_bool y
1013	depends on MICROCODE
1014
1015config MICROCODE_INTEL_EARLY
1016	def_bool n
1017
1018config MICROCODE_AMD_EARLY
1019	def_bool n
1020
1021config MICROCODE_EARLY
1022	bool "Early load microcode"
1023	depends on MICROCODE=y && BLK_DEV_INITRD
1024	select MICROCODE_INTEL_EARLY if MICROCODE_INTEL
1025	select MICROCODE_AMD_EARLY if MICROCODE_AMD
1026	default y
1027	help
1028	  This option provides functionality to read additional microcode data
1029	  at the beginning of initrd image. The data tells kernel to load
1030	  microcode to CPU's as early as possible. No functional change if no
1031	  microcode data is glued to the initrd, therefore it's safe to say Y.
1032
1033config X86_MSR
1034	tristate "/dev/cpu/*/msr - Model-specific register support"
1035	---help---
1036	  This device gives privileged processes access to the x86
1037	  Model-Specific Registers (MSRs).  It is a character device with
1038	  major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1039	  MSR accesses are directed to a specific CPU on multi-processor
1040	  systems.
1041
1042config X86_CPUID
1043	tristate "/dev/cpu/*/cpuid - CPU information support"
1044	---help---
1045	  This device gives processes access to the x86 CPUID instruction to
1046	  be executed on a specific processor.  It is a character device
1047	  with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1048	  /dev/cpu/31/cpuid.
1049
1050choice
1051	prompt "High Memory Support"
1052	default HIGHMEM4G
1053	depends on X86_32
1054
1055config NOHIGHMEM
1056	bool "off"
1057	---help---
1058	  Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1059	  However, the address space of 32-bit x86 processors is only 4
1060	  Gigabytes large. That means that, if you have a large amount of
1061	  physical memory, not all of it can be "permanently mapped" by the
1062	  kernel. The physical memory that's not permanently mapped is called
1063	  "high memory".
1064
1065	  If you are compiling a kernel which will never run on a machine with
1066	  more than 1 Gigabyte total physical RAM, answer "off" here (default
1067	  choice and suitable for most users). This will result in a "3GB/1GB"
1068	  split: 3GB are mapped so that each process sees a 3GB virtual memory
1069	  space and the remaining part of the 4GB virtual memory space is used
1070	  by the kernel to permanently map as much physical memory as
1071	  possible.
1072
1073	  If the machine has between 1 and 4 Gigabytes physical RAM, then
1074	  answer "4GB" here.
1075
1076	  If more than 4 Gigabytes is used then answer "64GB" here. This
1077	  selection turns Intel PAE (Physical Address Extension) mode on.
1078	  PAE implements 3-level paging on IA32 processors. PAE is fully
1079	  supported by Linux, PAE mode is implemented on all recent Intel
1080	  processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1081	  then the kernel will not boot on CPUs that don't support PAE!
1082
1083	  The actual amount of total physical memory will either be
1084	  auto detected or can be forced by using a kernel command line option
1085	  such as "mem=256M". (Try "man bootparam" or see the documentation of
1086	  your boot loader (lilo or loadlin) about how to pass options to the
1087	  kernel at boot time.)
1088
1089	  If unsure, say "off".
1090
1091config HIGHMEM4G
1092	bool "4GB"
1093	---help---
1094	  Select this if you have a 32-bit processor and between 1 and 4
1095	  gigabytes of physical RAM.
1096
1097config HIGHMEM64G
1098	bool "64GB"
1099	depends on !M486
1100	select X86_PAE
1101	---help---
1102	  Select this if you have a 32-bit processor and more than 4
1103	  gigabytes of physical RAM.
1104
1105endchoice
1106
1107choice
1108	prompt "Memory split" if EXPERT
1109	default VMSPLIT_3G
1110	depends on X86_32
1111	---help---
1112	  Select the desired split between kernel and user memory.
1113
1114	  If the address range available to the kernel is less than the
1115	  physical memory installed, the remaining memory will be available
1116	  as "high memory". Accessing high memory is a little more costly
1117	  than low memory, as it needs to be mapped into the kernel first.
1118	  Note that increasing the kernel address space limits the range
1119	  available to user programs, making the address space there
1120	  tighter.  Selecting anything other than the default 3G/1G split
1121	  will also likely make your kernel incompatible with binary-only
1122	  kernel modules.
1123
1124	  If you are not absolutely sure what you are doing, leave this
1125	  option alone!
1126
1127	config VMSPLIT_3G
1128		bool "3G/1G user/kernel split"
1129	config VMSPLIT_3G_OPT
1130		depends on !X86_PAE
1131		bool "3G/1G user/kernel split (for full 1G low memory)"
1132	config VMSPLIT_2G
1133		bool "2G/2G user/kernel split"
1134	config VMSPLIT_2G_OPT
1135		depends on !X86_PAE
1136		bool "2G/2G user/kernel split (for full 2G low memory)"
1137	config VMSPLIT_1G
1138		bool "1G/3G user/kernel split"
1139endchoice
1140
1141config PAGE_OFFSET
1142	hex
1143	default 0xB0000000 if VMSPLIT_3G_OPT
1144	default 0x80000000 if VMSPLIT_2G
1145	default 0x78000000 if VMSPLIT_2G_OPT
1146	default 0x40000000 if VMSPLIT_1G
1147	default 0xC0000000
1148	depends on X86_32
1149
1150config HIGHMEM
1151	def_bool y
1152	depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1153
1154config X86_PAE
1155	bool "PAE (Physical Address Extension) Support"
1156	depends on X86_32 && !HIGHMEM4G
1157	---help---
1158	  PAE is required for NX support, and furthermore enables
1159	  larger swapspace support for non-overcommit purposes. It
1160	  has the cost of more pagetable lookup overhead, and also
1161	  consumes more pagetable space per process.
1162
1163config ARCH_PHYS_ADDR_T_64BIT
1164	def_bool y
1165	depends on X86_64 || X86_PAE
1166
1167config ARCH_DMA_ADDR_T_64BIT
1168	def_bool y
1169	depends on X86_64 || HIGHMEM64G
1170
1171config DIRECT_GBPAGES
1172	bool "Enable 1GB pages for kernel pagetables" if EXPERT
1173	default y
1174	depends on X86_64
1175	---help---
1176	  Allow the kernel linear mapping to use 1GB pages on CPUs that
1177	  support it. This can improve the kernel's performance a tiny bit by
1178	  reducing TLB pressure. If in doubt, say "Y".
1179
1180# Common NUMA Features
1181config NUMA
1182	bool "Numa Memory Allocation and Scheduler Support"
1183	depends on SMP
1184	depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1185	default y if X86_BIGSMP
1186	---help---
1187	  Enable NUMA (Non Uniform Memory Access) support.
1188
1189	  The kernel will try to allocate memory used by a CPU on the
1190	  local memory controller of the CPU and add some more
1191	  NUMA awareness to the kernel.
1192
1193	  For 64-bit this is recommended if the system is Intel Core i7
1194	  (or later), AMD Opteron, or EM64T NUMA.
1195
1196	  For 32-bit this is only needed if you boot a 32-bit
1197	  kernel on a 64-bit NUMA platform.
1198
1199	  Otherwise, you should say N.
1200
1201config AMD_NUMA
1202	def_bool y
1203	prompt "Old style AMD Opteron NUMA detection"
1204	depends on X86_64 && NUMA && PCI
1205	---help---
1206	  Enable AMD NUMA node topology detection.  You should say Y here if
1207	  you have a multi processor AMD system. This uses an old method to
1208	  read the NUMA configuration directly from the builtin Northbridge
1209	  of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1210	  which also takes priority if both are compiled in.
1211
1212config X86_64_ACPI_NUMA
1213	def_bool y
1214	prompt "ACPI NUMA detection"
1215	depends on X86_64 && NUMA && ACPI && PCI
1216	select ACPI_NUMA
1217	---help---
1218	  Enable ACPI SRAT based node topology detection.
1219
1220# Some NUMA nodes have memory ranges that span
1221# other nodes.  Even though a pfn is valid and
1222# between a node's start and end pfns, it may not
1223# reside on that node.  See memmap_init_zone()
1224# for details.
1225config NODES_SPAN_OTHER_NODES
1226	def_bool y
1227	depends on X86_64_ACPI_NUMA
1228
1229config NUMA_EMU
1230	bool "NUMA emulation"
1231	depends on NUMA
1232	---help---
1233	  Enable NUMA emulation. A flat machine will be split
1234	  into virtual nodes when booted with "numa=fake=N", where N is the
1235	  number of nodes. This is only useful for debugging.
1236
1237config NODES_SHIFT
1238	int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1239	range 1 10
1240	default "10" if MAXSMP
1241	default "6" if X86_64
1242	default "3"
1243	depends on NEED_MULTIPLE_NODES
1244	---help---
1245	  Specify the maximum number of NUMA Nodes available on the target
1246	  system.  Increases memory reserved to accommodate various tables.
1247
1248config ARCH_HAVE_MEMORY_PRESENT
1249	def_bool y
1250	depends on X86_32 && DISCONTIGMEM
1251
1252config NEED_NODE_MEMMAP_SIZE
1253	def_bool y
1254	depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1255
1256config ARCH_FLATMEM_ENABLE
1257	def_bool y
1258	depends on X86_32 && !NUMA
1259
1260config ARCH_DISCONTIGMEM_ENABLE
1261	def_bool y
1262	depends on NUMA && X86_32
1263
1264config ARCH_DISCONTIGMEM_DEFAULT
1265	def_bool y
1266	depends on NUMA && X86_32
1267
1268config ARCH_SPARSEMEM_ENABLE
1269	def_bool y
1270	depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1271	select SPARSEMEM_STATIC if X86_32
1272	select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1273
1274config ARCH_SPARSEMEM_DEFAULT
1275	def_bool y
1276	depends on X86_64
1277
1278config ARCH_SELECT_MEMORY_MODEL
1279	def_bool y
1280	depends on ARCH_SPARSEMEM_ENABLE
1281
1282config ARCH_MEMORY_PROBE
1283	bool "Enable sysfs memory/probe interface"
1284	depends on X86_64 && MEMORY_HOTPLUG
1285	help
1286	  This option enables a sysfs memory/probe interface for testing.
1287	  See Documentation/memory-hotplug.txt for more information.
1288	  If you are unsure how to answer this question, answer N.
1289
1290config ARCH_PROC_KCORE_TEXT
1291	def_bool y
1292	depends on X86_64 && PROC_KCORE
1293
1294config ILLEGAL_POINTER_VALUE
1295       hex
1296       default 0 if X86_32
1297       default 0xdead000000000000 if X86_64
1298
1299source "mm/Kconfig"
1300
1301config HIGHPTE
1302	bool "Allocate 3rd-level pagetables from highmem"
1303	depends on HIGHMEM
1304	---help---
1305	  The VM uses one page table entry for each page of physical memory.
1306	  For systems with a lot of RAM, this can be wasteful of precious
1307	  low memory.  Setting this option will put user-space page table
1308	  entries in high memory.
1309
1310config X86_CHECK_BIOS_CORRUPTION
1311	bool "Check for low memory corruption"
1312	---help---
1313	  Periodically check for memory corruption in low memory, which
1314	  is suspected to be caused by BIOS.  Even when enabled in the
1315	  configuration, it is disabled at runtime.  Enable it by
1316	  setting "memory_corruption_check=1" on the kernel command
1317	  line.  By default it scans the low 64k of memory every 60
1318	  seconds; see the memory_corruption_check_size and
1319	  memory_corruption_check_period parameters in
1320	  Documentation/kernel-parameters.txt to adjust this.
1321
1322	  When enabled with the default parameters, this option has
1323	  almost no overhead, as it reserves a relatively small amount
1324	  of memory and scans it infrequently.  It both detects corruption
1325	  and prevents it from affecting the running system.
1326
1327	  It is, however, intended as a diagnostic tool; if repeatable
1328	  BIOS-originated corruption always affects the same memory,
1329	  you can use memmap= to prevent the kernel from using that
1330	  memory.
1331
1332config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1333	bool "Set the default setting of memory_corruption_check"
1334	depends on X86_CHECK_BIOS_CORRUPTION
1335	default y
1336	---help---
1337	  Set whether the default state of memory_corruption_check is
1338	  on or off.
1339
1340config X86_RESERVE_LOW
1341	int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1342	default 64
1343	range 4 640
1344	---help---
1345	  Specify the amount of low memory to reserve for the BIOS.
1346
1347	  The first page contains BIOS data structures that the kernel
1348	  must not use, so that page must always be reserved.
1349
1350	  By default we reserve the first 64K of physical RAM, as a
1351	  number of BIOSes are known to corrupt that memory range
1352	  during events such as suspend/resume or monitor cable
1353	  insertion, so it must not be used by the kernel.
1354
1355	  You can set this to 4 if you are absolutely sure that you
1356	  trust the BIOS to get all its memory reservations and usages
1357	  right.  If you know your BIOS have problems beyond the
1358	  default 64K area, you can set this to 640 to avoid using the
1359	  entire low memory range.
1360
1361	  If you have doubts about the BIOS (e.g. suspend/resume does
1362	  not work or there's kernel crashes after certain hardware
1363	  hotplug events) then you might want to enable
1364	  X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1365	  typical corruption patterns.
1366
1367	  Leave this to the default value of 64 if you are unsure.
1368
1369config MATH_EMULATION
1370	bool
1371	prompt "Math emulation" if X86_32
1372	---help---
1373	  Linux can emulate a math coprocessor (used for floating point
1374	  operations) if you don't have one. 486DX and Pentium processors have
1375	  a math coprocessor built in, 486SX and 386 do not, unless you added
1376	  a 487DX or 387, respectively. (The messages during boot time can
1377	  give you some hints here ["man dmesg"].) Everyone needs either a
1378	  coprocessor or this emulation.
1379
1380	  If you don't have a math coprocessor, you need to say Y here; if you
1381	  say Y here even though you have a coprocessor, the coprocessor will
1382	  be used nevertheless. (This behavior can be changed with the kernel
1383	  command line option "no387", which comes handy if your coprocessor
1384	  is broken. Try "man bootparam" or see the documentation of your boot
1385	  loader (lilo or loadlin) about how to pass options to the kernel at
1386	  boot time.) This means that it is a good idea to say Y here if you
1387	  intend to use this kernel on different machines.
1388
1389	  More information about the internals of the Linux math coprocessor
1390	  emulation can be found in <file:arch/x86/math-emu/README>.
1391
1392	  If you are not sure, say Y; apart from resulting in a 66 KB bigger
1393	  kernel, it won't hurt.
1394
1395config MTRR
1396	def_bool y
1397	prompt "MTRR (Memory Type Range Register) support" if EXPERT
1398	---help---
1399	  On Intel P6 family processors (Pentium Pro, Pentium II and later)
1400	  the Memory Type Range Registers (MTRRs) may be used to control
1401	  processor access to memory ranges. This is most useful if you have
1402	  a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1403	  allows bus write transfers to be combined into a larger transfer
1404	  before bursting over the PCI/AGP bus. This can increase performance
1405	  of image write operations 2.5 times or more. Saying Y here creates a
1406	  /proc/mtrr file which may be used to manipulate your processor's
1407	  MTRRs. Typically the X server should use this.
1408
1409	  This code has a reasonably generic interface so that similar
1410	  control registers on other processors can be easily supported
1411	  as well:
1412
1413	  The Cyrix 6x86, 6x86MX and M II processors have Address Range
1414	  Registers (ARRs) which provide a similar functionality to MTRRs. For
1415	  these, the ARRs are used to emulate the MTRRs.
1416	  The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1417	  MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1418	  write-combining. All of these processors are supported by this code
1419	  and it makes sense to say Y here if you have one of them.
1420
1421	  Saying Y here also fixes a problem with buggy SMP BIOSes which only
1422	  set the MTRRs for the boot CPU and not for the secondary CPUs. This
1423	  can lead to all sorts of problems, so it's good to say Y here.
1424
1425	  You can safely say Y even if your machine doesn't have MTRRs, you'll
1426	  just add about 9 KB to your kernel.
1427
1428	  See <file:Documentation/x86/mtrr.txt> for more information.
1429
1430config MTRR_SANITIZER
1431	def_bool y
1432	prompt "MTRR cleanup support"
1433	depends on MTRR
1434	---help---
1435	  Convert MTRR layout from continuous to discrete, so X drivers can
1436	  add writeback entries.
1437
1438	  Can be disabled with disable_mtrr_cleanup on the kernel command line.
1439	  The largest mtrr entry size for a continuous block can be set with
1440	  mtrr_chunk_size.
1441
1442	  If unsure, say Y.
1443
1444config MTRR_SANITIZER_ENABLE_DEFAULT
1445	int "MTRR cleanup enable value (0-1)"
1446	range 0 1
1447	default "0"
1448	depends on MTRR_SANITIZER
1449	---help---
1450	  Enable mtrr cleanup default value
1451
1452config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1453	int "MTRR cleanup spare reg num (0-7)"
1454	range 0 7
1455	default "1"
1456	depends on MTRR_SANITIZER
1457	---help---
1458	  mtrr cleanup spare entries default, it can be changed via
1459	  mtrr_spare_reg_nr=N on the kernel command line.
1460
1461config X86_PAT
1462	def_bool y
1463	prompt "x86 PAT support" if EXPERT
1464	depends on MTRR
1465	---help---
1466	  Use PAT attributes to setup page level cache control.
1467
1468	  PATs are the modern equivalents of MTRRs and are much more
1469	  flexible than MTRRs.
1470
1471	  Say N here if you see bootup problems (boot crash, boot hang,
1472	  spontaneous reboots) or a non-working video driver.
1473
1474	  If unsure, say Y.
1475
1476config ARCH_USES_PG_UNCACHED
1477	def_bool y
1478	depends on X86_PAT
1479
1480config ARCH_RANDOM
1481	def_bool y
1482	prompt "x86 architectural random number generator" if EXPERT
1483	---help---
1484	  Enable the x86 architectural RDRAND instruction
1485	  (Intel Bull Mountain technology) to generate random numbers.
1486	  If supported, this is a high bandwidth, cryptographically
1487	  secure hardware random number generator.
1488
1489config X86_SMAP
1490	def_bool y
1491	prompt "Supervisor Mode Access Prevention" if EXPERT
1492	---help---
1493	  Supervisor Mode Access Prevention (SMAP) is a security
1494	  feature in newer Intel processors.  There is a small
1495	  performance cost if this enabled and turned on; there is
1496	  also a small increase in the kernel size if this is enabled.
1497
1498	  If unsure, say Y.
1499
1500config EFI
1501	bool "EFI runtime service support"
1502	depends on ACPI
1503	select UCS2_STRING
1504	---help---
1505	  This enables the kernel to use EFI runtime services that are
1506	  available (such as the EFI variable services).
1507
1508	  This option is only useful on systems that have EFI firmware.
1509	  In addition, you should use the latest ELILO loader available
1510	  at <http://elilo.sourceforge.net> in order to take advantage
1511	  of EFI runtime services. However, even with this option, the
1512	  resultant kernel should continue to boot on existing non-EFI
1513	  platforms.
1514
1515config EFI_STUB
1516       bool "EFI stub support"
1517       depends on EFI
1518       ---help---
1519          This kernel feature allows a bzImage to be loaded directly
1520	  by EFI firmware without the use of a bootloader.
1521
1522	  See Documentation/efi-stub.txt for more information.
1523
1524config EFI_MIXED
1525	bool "EFI mixed-mode support"
1526	depends on EFI_STUB && X86_64
1527	---help---
1528	   Enabling this feature allows a 64-bit kernel to be booted
1529	   on a 32-bit firmware, provided that your CPU supports 64-bit
1530	   mode.
1531
1532	   Note that it is not possible to boot a mixed-mode enabled
1533	   kernel via the EFI boot stub - a bootloader that supports
1534	   the EFI handover protocol must be used.
1535
1536	   If unsure, say N.
1537
1538config SECCOMP
1539	def_bool y
1540	prompt "Enable seccomp to safely compute untrusted bytecode"
1541	---help---
1542	  This kernel feature is useful for number crunching applications
1543	  that may need to compute untrusted bytecode during their
1544	  execution. By using pipes or other transports made available to
1545	  the process as file descriptors supporting the read/write
1546	  syscalls, it's possible to isolate those applications in
1547	  their own address space using seccomp. Once seccomp is
1548	  enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1549	  and the task is only allowed to execute a few safe syscalls
1550	  defined by each seccomp mode.
1551
1552	  If unsure, say Y. Only embedded should say N here.
1553
1554source kernel/Kconfig.hz
1555
1556config KEXEC
1557	bool "kexec system call"
1558	---help---
1559	  kexec is a system call that implements the ability to shutdown your
1560	  current kernel, and to start another kernel.  It is like a reboot
1561	  but it is independent of the system firmware.   And like a reboot
1562	  you can start any kernel with it, not just Linux.
1563
1564	  The name comes from the similarity to the exec system call.
1565
1566	  It is an ongoing process to be certain the hardware in a machine
1567	  is properly shutdown, so do not be surprised if this code does not
1568	  initially work for you.  As of this writing the exact hardware
1569	  interface is strongly in flux, so no good recommendation can be
1570	  made.
1571
1572config CRASH_DUMP
1573	bool "kernel crash dumps"
1574	depends on X86_64 || (X86_32 && HIGHMEM)
1575	---help---
1576	  Generate crash dump after being started by kexec.
1577	  This should be normally only set in special crash dump kernels
1578	  which are loaded in the main kernel with kexec-tools into
1579	  a specially reserved region and then later executed after
1580	  a crash by kdump/kexec. The crash dump kernel must be compiled
1581	  to a memory address not used by the main kernel or BIOS using
1582	  PHYSICAL_START, or it must be built as a relocatable image
1583	  (CONFIG_RELOCATABLE=y).
1584	  For more details see Documentation/kdump/kdump.txt
1585
1586config KEXEC_JUMP
1587	bool "kexec jump"
1588	depends on KEXEC && HIBERNATION
1589	---help---
1590	  Jump between original kernel and kexeced kernel and invoke
1591	  code in physical address mode via KEXEC
1592
1593config PHYSICAL_START
1594	hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1595	default "0x1000000"
1596	---help---
1597	  This gives the physical address where the kernel is loaded.
1598
1599	  If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1600	  bzImage will decompress itself to above physical address and
1601	  run from there. Otherwise, bzImage will run from the address where
1602	  it has been loaded by the boot loader and will ignore above physical
1603	  address.
1604
1605	  In normal kdump cases one does not have to set/change this option
1606	  as now bzImage can be compiled as a completely relocatable image
1607	  (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1608	  address. This option is mainly useful for the folks who don't want
1609	  to use a bzImage for capturing the crash dump and want to use a
1610	  vmlinux instead. vmlinux is not relocatable hence a kernel needs
1611	  to be specifically compiled to run from a specific memory area
1612	  (normally a reserved region) and this option comes handy.
1613
1614	  So if you are using bzImage for capturing the crash dump,
1615	  leave the value here unchanged to 0x1000000 and set
1616	  CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
1617	  for capturing the crash dump change this value to start of
1618	  the reserved region.  In other words, it can be set based on
1619	  the "X" value as specified in the "crashkernel=YM@XM"
1620	  command line boot parameter passed to the panic-ed
1621	  kernel. Please take a look at Documentation/kdump/kdump.txt
1622	  for more details about crash dumps.
1623
1624	  Usage of bzImage for capturing the crash dump is recommended as
1625	  one does not have to build two kernels. Same kernel can be used
1626	  as production kernel and capture kernel. Above option should have
1627	  gone away after relocatable bzImage support is introduced. But it
1628	  is present because there are users out there who continue to use
1629	  vmlinux for dump capture. This option should go away down the
1630	  line.
1631
1632	  Don't change this unless you know what you are doing.
1633
1634config RELOCATABLE
1635	bool "Build a relocatable kernel"
1636	default y
1637	---help---
1638	  This builds a kernel image that retains relocation information
1639	  so it can be loaded someplace besides the default 1MB.
1640	  The relocations tend to make the kernel binary about 10% larger,
1641	  but are discarded at runtime.
1642
1643	  One use is for the kexec on panic case where the recovery kernel
1644	  must live at a different physical address than the primary
1645	  kernel.
1646
1647	  Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1648	  it has been loaded at and the compile time physical address
1649	  (CONFIG_PHYSICAL_START) is used as the minimum location.
1650
1651config RANDOMIZE_BASE
1652	bool "Randomize the address of the kernel image"
1653	depends on RELOCATABLE
1654	depends on !HIBERNATION
1655	default n
1656	---help---
1657	   Randomizes the physical and virtual address at which the
1658	   kernel image is decompressed, as a security feature that
1659	   deters exploit attempts relying on knowledge of the location
1660	   of kernel internals.
1661
1662	   Entropy is generated using the RDRAND instruction if it is
1663	   supported. If RDTSC is supported, it is used as well. If
1664	   neither RDRAND nor RDTSC are supported, then randomness is
1665	   read from the i8254 timer.
1666
1667	   The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
1668	   and aligned according to PHYSICAL_ALIGN. Since the kernel is
1669	   built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
1670	   minimum of 2MiB, only 10 bits of entropy is theoretically
1671	   possible. At best, due to page table layouts, 64-bit can use
1672	   9 bits of entropy and 32-bit uses 8 bits.
1673
1674	   If unsure, say N.
1675
1676config RANDOMIZE_BASE_MAX_OFFSET
1677	hex "Maximum kASLR offset allowed" if EXPERT
1678	depends on RANDOMIZE_BASE
1679	range 0x0 0x20000000 if X86_32
1680	default "0x20000000" if X86_32
1681	range 0x0 0x40000000 if X86_64
1682	default "0x40000000" if X86_64
1683	---help---
1684	  The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
1685	  memory is used to determine the maximal offset in bytes that will
1686	  be applied to the kernel when kernel Address Space Layout
1687	  Randomization (kASLR) is active. This must be a multiple of
1688	  PHYSICAL_ALIGN.
1689
1690	  On 32-bit this is limited to 512MiB by page table layouts. The
1691	  default is 512MiB.
1692
1693	  On 64-bit this is limited by how the kernel fixmap page table is
1694	  positioned, so this cannot be larger than 1GiB currently. Without
1695	  RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
1696	  and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
1697	  modules area will shrink to compensate, up to the current maximum
1698	  1GiB to 1GiB split. The default is 1GiB.
1699
1700	  If unsure, leave at the default value.
1701
1702# Relocation on x86 needs some additional build support
1703config X86_NEED_RELOCS
1704	def_bool y
1705	depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
1706
1707config PHYSICAL_ALIGN
1708	hex "Alignment value to which kernel should be aligned"
1709	default "0x200000"
1710	range 0x2000 0x1000000 if X86_32
1711	range 0x200000 0x1000000 if X86_64
1712	---help---
1713	  This value puts the alignment restrictions on physical address
1714	  where kernel is loaded and run from. Kernel is compiled for an
1715	  address which meets above alignment restriction.
1716
1717	  If bootloader loads the kernel at a non-aligned address and
1718	  CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1719	  address aligned to above value and run from there.
1720
1721	  If bootloader loads the kernel at a non-aligned address and
1722	  CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1723	  load address and decompress itself to the address it has been
1724	  compiled for and run from there. The address for which kernel is
1725	  compiled already meets above alignment restrictions. Hence the
1726	  end result is that kernel runs from a physical address meeting
1727	  above alignment restrictions.
1728
1729	  On 32-bit this value must be a multiple of 0x2000. On 64-bit
1730	  this value must be a multiple of 0x200000.
1731
1732	  Don't change this unless you know what you are doing.
1733
1734config HOTPLUG_CPU
1735	bool "Support for hot-pluggable CPUs"
1736	depends on SMP
1737	---help---
1738	  Say Y here to allow turning CPUs off and on. CPUs can be
1739	  controlled through /sys/devices/system/cpu.
1740	  ( Note: power management support will enable this option
1741	    automatically on SMP systems. )
1742	  Say N if you want to disable CPU hotplug.
1743
1744config BOOTPARAM_HOTPLUG_CPU0
1745	bool "Set default setting of cpu0_hotpluggable"
1746	default n
1747	depends on HOTPLUG_CPU
1748	---help---
1749	  Set whether default state of cpu0_hotpluggable is on or off.
1750
1751	  Say Y here to enable CPU0 hotplug by default. If this switch
1752	  is turned on, there is no need to give cpu0_hotplug kernel
1753	  parameter and the CPU0 hotplug feature is enabled by default.
1754
1755	  Please note: there are two known CPU0 dependencies if you want
1756	  to enable the CPU0 hotplug feature either by this switch or by
1757	  cpu0_hotplug kernel parameter.
1758
1759	  First, resume from hibernate or suspend always starts from CPU0.
1760	  So hibernate and suspend are prevented if CPU0 is offline.
1761
1762	  Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1763	  offline if any interrupt can not migrate out of CPU0. There may
1764	  be other CPU0 dependencies.
1765
1766	  Please make sure the dependencies are under your control before
1767	  you enable this feature.
1768
1769	  Say N if you don't want to enable CPU0 hotplug feature by default.
1770	  You still can enable the CPU0 hotplug feature at boot by kernel
1771	  parameter cpu0_hotplug.
1772
1773config DEBUG_HOTPLUG_CPU0
1774	def_bool n
1775	prompt "Debug CPU0 hotplug"
1776	depends on HOTPLUG_CPU
1777	---help---
1778	  Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1779	  soon as possible and boots up userspace with CPU0 offlined. User
1780	  can online CPU0 back after boot time.
1781
1782	  To debug CPU0 hotplug, you need to enable CPU0 offline/online
1783	  feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
1784	  compilation or giving cpu0_hotplug kernel parameter at boot.
1785
1786	  If unsure, say N.
1787
1788config COMPAT_VDSO
1789	def_bool n
1790	prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
1791	depends on X86_32 || IA32_EMULATION
1792	---help---
1793	  Certain buggy versions of glibc will crash if they are
1794	  presented with a 32-bit vDSO that is not mapped at the address
1795	  indicated in its segment table.
1796
1797	  The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
1798	  and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
1799	  49ad572a70b8aeb91e57483a11dd1b77e31c4468.  Glibc 2.3.3 is
1800	  the only released version with the bug, but OpenSUSE 9
1801	  contains a buggy "glibc 2.3.2".
1802
1803	  The symptom of the bug is that everything crashes on startup, saying:
1804	  dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
1805
1806	  Saying Y here changes the default value of the vdso32 boot
1807	  option from 1 to 0, which turns off the 32-bit vDSO entirely.
1808	  This works around the glibc bug but hurts performance.
1809
1810	  If unsure, say N: if you are compiling your own kernel, you
1811	  are unlikely to be using a buggy version of glibc.
1812
1813config CMDLINE_BOOL
1814	bool "Built-in kernel command line"
1815	---help---
1816	  Allow for specifying boot arguments to the kernel at
1817	  build time.  On some systems (e.g. embedded ones), it is
1818	  necessary or convenient to provide some or all of the
1819	  kernel boot arguments with the kernel itself (that is,
1820	  to not rely on the boot loader to provide them.)
1821
1822	  To compile command line arguments into the kernel,
1823	  set this option to 'Y', then fill in the
1824	  the boot arguments in CONFIG_CMDLINE.
1825
1826	  Systems with fully functional boot loaders (i.e. non-embedded)
1827	  should leave this option set to 'N'.
1828
1829config CMDLINE
1830	string "Built-in kernel command string"
1831	depends on CMDLINE_BOOL
1832	default ""
1833	---help---
1834	  Enter arguments here that should be compiled into the kernel
1835	  image and used at boot time.  If the boot loader provides a
1836	  command line at boot time, it is appended to this string to
1837	  form the full kernel command line, when the system boots.
1838
1839	  However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1840	  change this behavior.
1841
1842	  In most cases, the command line (whether built-in or provided
1843	  by the boot loader) should specify the device for the root
1844	  file system.
1845
1846config CMDLINE_OVERRIDE
1847	bool "Built-in command line overrides boot loader arguments"
1848	depends on CMDLINE_BOOL
1849	---help---
1850	  Set this option to 'Y' to have the kernel ignore the boot loader
1851	  command line, and use ONLY the built-in command line.
1852
1853	  This is used to work around broken boot loaders.  This should
1854	  be set to 'N' under normal conditions.
1855
1856endmenu
1857
1858config ARCH_ENABLE_MEMORY_HOTPLUG
1859	def_bool y
1860	depends on X86_64 || (X86_32 && HIGHMEM)
1861
1862config ARCH_ENABLE_MEMORY_HOTREMOVE
1863	def_bool y
1864	depends on MEMORY_HOTPLUG
1865
1866config USE_PERCPU_NUMA_NODE_ID
1867	def_bool y
1868	depends on NUMA
1869
1870config ARCH_ENABLE_SPLIT_PMD_PTLOCK
1871	def_bool y
1872	depends on X86_64 || X86_PAE
1873
1874menu "Power management and ACPI options"
1875
1876config ARCH_HIBERNATION_HEADER
1877	def_bool y
1878	depends on X86_64 && HIBERNATION
1879
1880source "kernel/power/Kconfig"
1881
1882source "drivers/acpi/Kconfig"
1883
1884source "drivers/sfi/Kconfig"
1885
1886config X86_APM_BOOT
1887	def_bool y
1888	depends on APM
1889
1890menuconfig APM
1891	tristate "APM (Advanced Power Management) BIOS support"
1892	depends on X86_32 && PM_SLEEP
1893	---help---
1894	  APM is a BIOS specification for saving power using several different
1895	  techniques. This is mostly useful for battery powered laptops with
1896	  APM compliant BIOSes. If you say Y here, the system time will be
1897	  reset after a RESUME operation, the /proc/apm device will provide
1898	  battery status information, and user-space programs will receive
1899	  notification of APM "events" (e.g. battery status change).
1900
1901	  If you select "Y" here, you can disable actual use of the APM
1902	  BIOS by passing the "apm=off" option to the kernel at boot time.
1903
1904	  Note that the APM support is almost completely disabled for
1905	  machines with more than one CPU.
1906
1907	  In order to use APM, you will need supporting software. For location
1908	  and more information, read <file:Documentation/power/apm-acpi.txt>
1909	  and the Battery Powered Linux mini-HOWTO, available from
1910	  <http://www.tldp.org/docs.html#howto>.
1911
1912	  This driver does not spin down disk drives (see the hdparm(8)
1913	  manpage ("man 8 hdparm") for that), and it doesn't turn off
1914	  VESA-compliant "green" monitors.
1915
1916	  This driver does not support the TI 4000M TravelMate and the ACER
1917	  486/DX4/75 because they don't have compliant BIOSes. Many "green"
1918	  desktop machines also don't have compliant BIOSes, and this driver
1919	  may cause those machines to panic during the boot phase.
1920
1921	  Generally, if you don't have a battery in your machine, there isn't
1922	  much point in using this driver and you should say N. If you get
1923	  random kernel OOPSes or reboots that don't seem to be related to
1924	  anything, try disabling/enabling this option (or disabling/enabling
1925	  APM in your BIOS).
1926
1927	  Some other things you should try when experiencing seemingly random,
1928	  "weird" problems:
1929
1930	  1) make sure that you have enough swap space and that it is
1931	  enabled.
1932	  2) pass the "no-hlt" option to the kernel
1933	  3) switch on floating point emulation in the kernel and pass
1934	  the "no387" option to the kernel
1935	  4) pass the "floppy=nodma" option to the kernel
1936	  5) pass the "mem=4M" option to the kernel (thereby disabling
1937	  all but the first 4 MB of RAM)
1938	  6) make sure that the CPU is not over clocked.
1939	  7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1940	  8) disable the cache from your BIOS settings
1941	  9) install a fan for the video card or exchange video RAM
1942	  10) install a better fan for the CPU
1943	  11) exchange RAM chips
1944	  12) exchange the motherboard.
1945
1946	  To compile this driver as a module, choose M here: the
1947	  module will be called apm.
1948
1949if APM
1950
1951config APM_IGNORE_USER_SUSPEND
1952	bool "Ignore USER SUSPEND"
1953	---help---
1954	  This option will ignore USER SUSPEND requests. On machines with a
1955	  compliant APM BIOS, you want to say N. However, on the NEC Versa M
1956	  series notebooks, it is necessary to say Y because of a BIOS bug.
1957
1958config APM_DO_ENABLE
1959	bool "Enable PM at boot time"
1960	---help---
1961	  Enable APM features at boot time. From page 36 of the APM BIOS
1962	  specification: "When disabled, the APM BIOS does not automatically
1963	  power manage devices, enter the Standby State, enter the Suspend
1964	  State, or take power saving steps in response to CPU Idle calls."
1965	  This driver will make CPU Idle calls when Linux is idle (unless this
1966	  feature is turned off -- see "Do CPU IDLE calls", below). This
1967	  should always save battery power, but more complicated APM features
1968	  will be dependent on your BIOS implementation. You may need to turn
1969	  this option off if your computer hangs at boot time when using APM
1970	  support, or if it beeps continuously instead of suspending. Turn
1971	  this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1972	  T400CDT. This is off by default since most machines do fine without
1973	  this feature.
1974
1975config APM_CPU_IDLE
1976	depends on CPU_IDLE
1977	bool "Make CPU Idle calls when idle"
1978	---help---
1979	  Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1980	  On some machines, this can activate improved power savings, such as
1981	  a slowed CPU clock rate, when the machine is idle. These idle calls
1982	  are made after the idle loop has run for some length of time (e.g.,
1983	  333 mS). On some machines, this will cause a hang at boot time or
1984	  whenever the CPU becomes idle. (On machines with more than one CPU,
1985	  this option does nothing.)
1986
1987config APM_DISPLAY_BLANK
1988	bool "Enable console blanking using APM"
1989	---help---
1990	  Enable console blanking using the APM. Some laptops can use this to
1991	  turn off the LCD backlight when the screen blanker of the Linux
1992	  virtual console blanks the screen. Note that this is only used by
1993	  the virtual console screen blanker, and won't turn off the backlight
1994	  when using the X Window system. This also doesn't have anything to
1995	  do with your VESA-compliant power-saving monitor. Further, this
1996	  option doesn't work for all laptops -- it might not turn off your
1997	  backlight at all, or it might print a lot of errors to the console,
1998	  especially if you are using gpm.
1999
2000config APM_ALLOW_INTS
2001	bool "Allow interrupts during APM BIOS calls"
2002	---help---
2003	  Normally we disable external interrupts while we are making calls to
2004	  the APM BIOS as a measure to lessen the effects of a badly behaving
2005	  BIOS implementation.  The BIOS should reenable interrupts if it
2006	  needs to.  Unfortunately, some BIOSes do not -- especially those in
2007	  many of the newer IBM Thinkpads.  If you experience hangs when you
2008	  suspend, try setting this to Y.  Otherwise, say N.
2009
2010endif # APM
2011
2012source "drivers/cpufreq/Kconfig"
2013
2014source "drivers/cpuidle/Kconfig"
2015
2016source "drivers/idle/Kconfig"
2017
2018endmenu
2019
2020
2021menu "Bus options (PCI etc.)"
2022
2023config PCI
2024	bool "PCI support"
2025	default y
2026	---help---
2027	  Find out whether you have a PCI motherboard. PCI is the name of a
2028	  bus system, i.e. the way the CPU talks to the other stuff inside
2029	  your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2030	  VESA. If you have PCI, say Y, otherwise N.
2031
2032choice
2033	prompt "PCI access mode"
2034	depends on X86_32 && PCI
2035	default PCI_GOANY
2036	---help---
2037	  On PCI systems, the BIOS can be used to detect the PCI devices and
2038	  determine their configuration. However, some old PCI motherboards
2039	  have BIOS bugs and may crash if this is done. Also, some embedded
2040	  PCI-based systems don't have any BIOS at all. Linux can also try to
2041	  detect the PCI hardware directly without using the BIOS.
2042
2043	  With this option, you can specify how Linux should detect the
2044	  PCI devices. If you choose "BIOS", the BIOS will be used,
2045	  if you choose "Direct", the BIOS won't be used, and if you
2046	  choose "MMConfig", then PCI Express MMCONFIG will be used.
2047	  If you choose "Any", the kernel will try MMCONFIG, then the
2048	  direct access method and falls back to the BIOS if that doesn't
2049	  work. If unsure, go with the default, which is "Any".
2050
2051config PCI_GOBIOS
2052	bool "BIOS"
2053
2054config PCI_GOMMCONFIG
2055	bool "MMConfig"
2056
2057config PCI_GODIRECT
2058	bool "Direct"
2059
2060config PCI_GOOLPC
2061	bool "OLPC XO-1"
2062	depends on OLPC
2063
2064config PCI_GOANY
2065	bool "Any"
2066
2067endchoice
2068
2069config PCI_BIOS
2070	def_bool y
2071	depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2072
2073# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2074config PCI_DIRECT
2075	def_bool y
2076	depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2077
2078config PCI_MMCONFIG
2079	def_bool y
2080	depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2081
2082config PCI_OLPC
2083	def_bool y
2084	depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2085
2086config PCI_XEN
2087	def_bool y
2088	depends on PCI && XEN
2089	select SWIOTLB_XEN
2090
2091config PCI_DOMAINS
2092	def_bool y
2093	depends on PCI
2094
2095config PCI_MMCONFIG
2096	bool "Support mmconfig PCI config space access"
2097	depends on X86_64 && PCI && ACPI
2098
2099config PCI_CNB20LE_QUIRK
2100	bool "Read CNB20LE Host Bridge Windows" if EXPERT
2101	depends on PCI
2102	help
2103	  Read the PCI windows out of the CNB20LE host bridge. This allows
2104	  PCI hotplug to work on systems with the CNB20LE chipset which do
2105	  not have ACPI.
2106
2107	  There's no public spec for this chipset, and this functionality
2108	  is known to be incomplete.
2109
2110	  You should say N unless you know you need this.
2111
2112source "drivers/pci/pcie/Kconfig"
2113
2114source "drivers/pci/Kconfig"
2115
2116# x86_64 have no ISA slots, but can have ISA-style DMA.
2117config ISA_DMA_API
2118	bool "ISA-style DMA support" if (X86_64 && EXPERT)
2119	default y
2120	help
2121	  Enables ISA-style DMA support for devices requiring such controllers.
2122	  If unsure, say Y.
2123
2124if X86_32
2125
2126config ISA
2127	bool "ISA support"
2128	---help---
2129	  Find out whether you have ISA slots on your motherboard.  ISA is the
2130	  name of a bus system, i.e. the way the CPU talks to the other stuff
2131	  inside your box.  Other bus systems are PCI, EISA, MicroChannel
2132	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
2133	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
2134
2135config EISA
2136	bool "EISA support"
2137	depends on ISA
2138	---help---
2139	  The Extended Industry Standard Architecture (EISA) bus was
2140	  developed as an open alternative to the IBM MicroChannel bus.
2141
2142	  The EISA bus provided some of the features of the IBM MicroChannel
2143	  bus while maintaining backward compatibility with cards made for
2144	  the older ISA bus.  The EISA bus saw limited use between 1988 and
2145	  1995 when it was made obsolete by the PCI bus.
2146
2147	  Say Y here if you are building a kernel for an EISA-based machine.
2148
2149	  Otherwise, say N.
2150
2151source "drivers/eisa/Kconfig"
2152
2153config SCx200
2154	tristate "NatSemi SCx200 support"
2155	---help---
2156	  This provides basic support for National Semiconductor's
2157	  (now AMD's) Geode processors.  The driver probes for the
2158	  PCI-IDs of several on-chip devices, so its a good dependency
2159	  for other scx200_* drivers.
2160
2161	  If compiled as a module, the driver is named scx200.
2162
2163config SCx200HR_TIMER
2164	tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2165	depends on SCx200
2166	default y
2167	---help---
2168	  This driver provides a clocksource built upon the on-chip
2169	  27MHz high-resolution timer.  Its also a workaround for
2170	  NSC Geode SC-1100's buggy TSC, which loses time when the
2171	  processor goes idle (as is done by the scheduler).  The
2172	  other workaround is idle=poll boot option.
2173
2174config OLPC
2175	bool "One Laptop Per Child support"
2176	depends on !X86_PAE
2177	select GPIOLIB
2178	select OF
2179	select OF_PROMTREE
2180	select IRQ_DOMAIN
2181	---help---
2182	  Add support for detecting the unique features of the OLPC
2183	  XO hardware.
2184
2185config OLPC_XO1_PM
2186	bool "OLPC XO-1 Power Management"
2187	depends on OLPC && MFD_CS5535 && PM_SLEEP
2188	select MFD_CORE
2189	---help---
2190	  Add support for poweroff and suspend of the OLPC XO-1 laptop.
2191
2192config OLPC_XO1_RTC
2193	bool "OLPC XO-1 Real Time Clock"
2194	depends on OLPC_XO1_PM && RTC_DRV_CMOS
2195	---help---
2196	  Add support for the XO-1 real time clock, which can be used as a
2197	  programmable wakeup source.
2198
2199config OLPC_XO1_SCI
2200	bool "OLPC XO-1 SCI extras"
2201	depends on OLPC && OLPC_XO1_PM
2202	depends on INPUT=y
2203	select POWER_SUPPLY
2204	select GPIO_CS5535
2205	select MFD_CORE
2206	---help---
2207	  Add support for SCI-based features of the OLPC XO-1 laptop:
2208	   - EC-driven system wakeups
2209	   - Power button
2210	   - Ebook switch
2211	   - Lid switch
2212	   - AC adapter status updates
2213	   - Battery status updates
2214
2215config OLPC_XO15_SCI
2216	bool "OLPC XO-1.5 SCI extras"
2217	depends on OLPC && ACPI
2218	select POWER_SUPPLY
2219	---help---
2220	  Add support for SCI-based features of the OLPC XO-1.5 laptop:
2221	   - EC-driven system wakeups
2222	   - AC adapter status updates
2223	   - Battery status updates
2224
2225config ALIX
2226	bool "PCEngines ALIX System Support (LED setup)"
2227	select GPIOLIB
2228	---help---
2229	  This option enables system support for the PCEngines ALIX.
2230	  At present this just sets up LEDs for GPIO control on
2231	  ALIX2/3/6 boards.  However, other system specific setup should
2232	  get added here.
2233
2234	  Note: You must still enable the drivers for GPIO and LED support
2235	  (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2236
2237	  Note: You have to set alix.force=1 for boards with Award BIOS.
2238
2239config NET5501
2240	bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2241	select GPIOLIB
2242	---help---
2243	  This option enables system support for the Soekris Engineering net5501.
2244
2245config GEOS
2246	bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2247	select GPIOLIB
2248	depends on DMI
2249	---help---
2250	  This option enables system support for the Traverse Technologies GEOS.
2251
2252config TS5500
2253	bool "Technologic Systems TS-5500 platform support"
2254	depends on MELAN
2255	select CHECK_SIGNATURE
2256	select NEW_LEDS
2257	select LEDS_CLASS
2258	---help---
2259	  This option enables system support for the Technologic Systems TS-5500.
2260
2261endif # X86_32
2262
2263config AMD_NB
2264	def_bool y
2265	depends on CPU_SUP_AMD && PCI
2266
2267source "drivers/pcmcia/Kconfig"
2268
2269source "drivers/pci/hotplug/Kconfig"
2270
2271config RAPIDIO
2272	tristate "RapidIO support"
2273	depends on PCI
2274	default n
2275	help
2276	  If enabled this option will include drivers and the core
2277	  infrastructure code to support RapidIO interconnect devices.
2278
2279source "drivers/rapidio/Kconfig"
2280
2281config X86_SYSFB
2282	bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2283	help
2284	  Firmwares often provide initial graphics framebuffers so the BIOS,
2285	  bootloader or kernel can show basic video-output during boot for
2286	  user-guidance and debugging. Historically, x86 used the VESA BIOS
2287	  Extensions and EFI-framebuffers for this, which are mostly limited
2288	  to x86.
2289	  This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2290	  framebuffers so the new generic system-framebuffer drivers can be
2291	  used on x86. If the framebuffer is not compatible with the generic
2292	  modes, it is adverticed as fallback platform framebuffer so legacy
2293	  drivers like efifb, vesafb and uvesafb can pick it up.
2294	  If this option is not selected, all system framebuffers are always
2295	  marked as fallback platform framebuffers as usual.
2296
2297	  Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2298	  not be able to pick up generic system framebuffers if this option
2299	  is selected. You are highly encouraged to enable simplefb as
2300	  replacement if you select this option. simplefb can correctly deal
2301	  with generic system framebuffers. But you should still keep vesafb
2302	  and others enabled as fallback if a system framebuffer is
2303	  incompatible with simplefb.
2304
2305	  If unsure, say Y.
2306
2307endmenu
2308
2309
2310menu "Executable file formats / Emulations"
2311
2312source "fs/Kconfig.binfmt"
2313
2314config IA32_EMULATION
2315	bool "IA32 Emulation"
2316	depends on X86_64
2317	select BINFMT_ELF
2318	select COMPAT_BINFMT_ELF
2319	select HAVE_UID16
2320	---help---
2321	  Include code to run legacy 32-bit programs under a
2322	  64-bit kernel. You should likely turn this on, unless you're
2323	  100% sure that you don't have any 32-bit programs left.
2324
2325config IA32_AOUT
2326	tristate "IA32 a.out support"
2327	depends on IA32_EMULATION
2328	---help---
2329	  Support old a.out binaries in the 32bit emulation.
2330
2331config X86_X32
2332	bool "x32 ABI for 64-bit mode"
2333	depends on X86_64 && IA32_EMULATION
2334	---help---
2335	  Include code to run binaries for the x32 native 32-bit ABI
2336	  for 64-bit processors.  An x32 process gets access to the
2337	  full 64-bit register file and wide data path while leaving
2338	  pointers at 32 bits for smaller memory footprint.
2339
2340	  You will need a recent binutils (2.22 or later) with
2341	  elf32_x86_64 support enabled to compile a kernel with this
2342	  option set.
2343
2344config COMPAT
2345	def_bool y
2346	depends on IA32_EMULATION || X86_X32
2347	select ARCH_WANT_OLD_COMPAT_IPC
2348
2349if COMPAT
2350config COMPAT_FOR_U64_ALIGNMENT
2351	def_bool y
2352
2353config SYSVIPC_COMPAT
2354	def_bool y
2355	depends on SYSVIPC
2356
2357config KEYS_COMPAT
2358	def_bool y
2359	depends on KEYS
2360endif
2361
2362endmenu
2363
2364
2365config HAVE_ATOMIC_IOMAP
2366	def_bool y
2367	depends on X86_32
2368
2369config X86_DEV_DMA_OPS
2370	bool
2371	depends on X86_64 || STA2X11
2372
2373config X86_DMA_REMAP
2374	bool
2375	depends on STA2X11
2376
2377config IOSF_MBI
2378	bool
2379	depends on PCI
2380	---help---
2381	  To be selected by modules requiring access to the Intel OnChip System
2382	  Fabric (IOSF) Sideband MailBox Interface (MBI). For MBI platforms
2383	  enumerable by PCI.
2384
2385source "net/Kconfig"
2386
2387source "drivers/Kconfig"
2388
2389source "drivers/firmware/Kconfig"
2390
2391source "fs/Kconfig"
2392
2393source "arch/x86/Kconfig.debug"
2394
2395source "security/Kconfig"
2396
2397source "crypto/Kconfig"
2398
2399source "arch/x86/kvm/Kconfig"
2400
2401source "lib/Kconfig"
2402