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1 # Select 32 or 64 bit
2 config 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
9 config X86_32
10 def_bool y
11 depends on !64BIT
12 select CLKSRC_I8253
13 select HAVE_UID16
14
15 config 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
22 config X86
23 def_bool y
24 select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
25 select ARCH_MIGHT_HAVE_PC_PARPORT
26 select HAVE_AOUT if X86_32
27 select HAVE_UNSTABLE_SCHED_CLOCK
28 select ARCH_SUPPORTS_NUMA_BALANCING
29 select ARCH_WANTS_PROT_NUMA_PROT_NONE
30 select HAVE_IDE
31 select HAVE_OPROFILE
32 select HAVE_PCSPKR_PLATFORM
33 select HAVE_PERF_EVENTS
34 select HAVE_IOREMAP_PROT
35 select HAVE_KPROBES
36 select HAVE_MEMBLOCK
37 select HAVE_MEMBLOCK_NODE_MAP
38 select ARCH_DISCARD_MEMBLOCK
39 select ARCH_WANT_OPTIONAL_GPIOLIB
40 select ARCH_WANT_FRAME_POINTERS
41 select HAVE_DMA_ATTRS
42 select HAVE_DMA_CONTIGUOUS if !SWIOTLB
43 select HAVE_KRETPROBES
44 select HAVE_OPTPROBES
45 select HAVE_KPROBES_ON_FTRACE
46 select HAVE_FTRACE_MCOUNT_RECORD
47 select HAVE_FENTRY if X86_64
48 select HAVE_C_RECORDMCOUNT
49 select HAVE_DYNAMIC_FTRACE
50 select HAVE_DYNAMIC_FTRACE_WITH_REGS
51 select HAVE_FUNCTION_TRACER
52 select HAVE_FUNCTION_GRAPH_TRACER
53 select HAVE_FUNCTION_GRAPH_FP_TEST
54 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
55 select HAVE_SYSCALL_TRACEPOINTS
56 select SYSCTL_EXCEPTION_TRACE
57 select HAVE_KVM
58 select HAVE_ARCH_KGDB
59 select HAVE_ARCH_TRACEHOOK
60 select HAVE_GENERIC_DMA_COHERENT if X86_32
61 select HAVE_EFFICIENT_UNALIGNED_ACCESS
62 select USER_STACKTRACE_SUPPORT
63 select HAVE_REGS_AND_STACK_ACCESS_API
64 select HAVE_DMA_API_DEBUG
65 select HAVE_KERNEL_GZIP
66 select HAVE_KERNEL_BZIP2
67 select HAVE_KERNEL_LZMA
68 select HAVE_KERNEL_XZ
69 select HAVE_KERNEL_LZO
70 select HAVE_KERNEL_LZ4
71 select HAVE_HW_BREAKPOINT
72 select HAVE_MIXED_BREAKPOINTS_REGS
73 select PERF_EVENTS
74 select HAVE_PERF_EVENTS_NMI
75 select HAVE_PERF_REGS
76 select HAVE_PERF_USER_STACK_DUMP
77 select HAVE_DEBUG_KMEMLEAK
78 select ANON_INODES
79 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
80 select HAVE_CMPXCHG_LOCAL
81 select HAVE_CMPXCHG_DOUBLE
82 select HAVE_ARCH_KMEMCHECK
83 select HAVE_USER_RETURN_NOTIFIER
84 select ARCH_BINFMT_ELF_RANDOMIZE_PIE
85 select HAVE_ARCH_JUMP_LABEL
86 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
87 select SPARSE_IRQ
88 select GENERIC_FIND_FIRST_BIT
89 select GENERIC_IRQ_PROBE
90 select GENERIC_PENDING_IRQ if SMP
91 select GENERIC_IRQ_SHOW
92 select GENERIC_CLOCKEVENTS_MIN_ADJUST
93 select IRQ_FORCED_THREADING
94 select HAVE_BPF_JIT if X86_64
95 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
96 select CLKEVT_I8253
97 select ARCH_HAVE_NMI_SAFE_CMPXCHG
98 select GENERIC_IOMAP
99 select DCACHE_WORD_ACCESS
100 select GENERIC_SMP_IDLE_THREAD
101 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
102 select HAVE_ARCH_SECCOMP_FILTER
103 select BUILDTIME_EXTABLE_SORT
104 select GENERIC_CMOS_UPDATE
105 select HAVE_ARCH_SOFT_DIRTY
106 select CLOCKSOURCE_WATCHDOG
107 select GENERIC_CLOCKEVENTS
108 select ARCH_CLOCKSOURCE_DATA if X86_64
109 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
110 select GENERIC_TIME_VSYSCALL if X86_64
111 select KTIME_SCALAR if X86_32
112 select GENERIC_STRNCPY_FROM_USER
113 select GENERIC_STRNLEN_USER
114 select HAVE_CONTEXT_TRACKING if X86_64
115 select HAVE_IRQ_TIME_ACCOUNTING
116 select VIRT_TO_BUS
117 select MODULES_USE_ELF_REL if X86_32
118 select MODULES_USE_ELF_RELA if X86_64
119 select CLONE_BACKWARDS if X86_32
120 select ARCH_USE_BUILTIN_BSWAP
121 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
122 select OLD_SIGACTION if X86_32
123 select COMPAT_OLD_SIGACTION if IA32_EMULATION
124 select RTC_LIB
125 select HAVE_DEBUG_STACKOVERFLOW
126 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
127
128 config INSTRUCTION_DECODER
129 def_bool y
130 depends on KPROBES || PERF_EVENTS || UPROBES
131
132 config OUTPUT_FORMAT
133 string
134 default "elf32-i386" if X86_32
135 default "elf64-x86-64" if X86_64
136
137 config ARCH_DEFCONFIG
138 string
139 default "arch/x86/configs/i386_defconfig" if X86_32
140 default "arch/x86/configs/x86_64_defconfig" if X86_64
141
142 config LOCKDEP_SUPPORT
143 def_bool y
144
145 config STACKTRACE_SUPPORT
146 def_bool y
147
148 config HAVE_LATENCYTOP_SUPPORT
149 def_bool y
150
151 config MMU
152 def_bool y
153
154 config SBUS
155 bool
156
157 config NEED_DMA_MAP_STATE
158 def_bool y
159 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG
160
161 config NEED_SG_DMA_LENGTH
162 def_bool y
163
164 config GENERIC_ISA_DMA
165 def_bool y
166 depends on ISA_DMA_API
167
168 config GENERIC_BUG
169 def_bool y
170 depends on BUG
171 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
172
173 config GENERIC_BUG_RELATIVE_POINTERS
174 bool
175
176 config GENERIC_HWEIGHT
177 def_bool y
178
179 config ARCH_MAY_HAVE_PC_FDC
180 def_bool y
181 depends on ISA_DMA_API
182
183 config RWSEM_XCHGADD_ALGORITHM
184 def_bool y
185
186 config GENERIC_CALIBRATE_DELAY
187 def_bool y
188
189 config ARCH_HAS_CPU_RELAX
190 def_bool y
191
192 config ARCH_HAS_CACHE_LINE_SIZE
193 def_bool y
194
195 config ARCH_HAS_CPU_AUTOPROBE
196 def_bool y
197
198 config HAVE_SETUP_PER_CPU_AREA
199 def_bool y
200
201 config NEED_PER_CPU_EMBED_FIRST_CHUNK
202 def_bool y
203
204 config NEED_PER_CPU_PAGE_FIRST_CHUNK
205 def_bool y
206
207 config ARCH_HIBERNATION_POSSIBLE
208 def_bool y
209
210 config ARCH_SUSPEND_POSSIBLE
211 def_bool y
212
213 config ARCH_WANT_HUGE_PMD_SHARE
214 def_bool y
215
216 config ARCH_WANT_GENERAL_HUGETLB
217 def_bool y
218
219 config ZONE_DMA32
220 bool
221 default X86_64
222
223 config AUDIT_ARCH
224 bool
225 default X86_64
226
227 config ARCH_SUPPORTS_OPTIMIZED_INLINING
228 def_bool y
229
230 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
231 def_bool y
232
233 config HAVE_INTEL_TXT
234 def_bool y
235 depends on INTEL_IOMMU && ACPI
236
237 config X86_32_SMP
238 def_bool y
239 depends on X86_32 && SMP
240
241 config X86_64_SMP
242 def_bool y
243 depends on X86_64 && SMP
244
245 config X86_HT
246 def_bool y
247 depends on SMP
248
249 config X86_32_LAZY_GS
250 def_bool y
251 depends on X86_32 && !CC_STACKPROTECTOR
252
253 config ARCH_HWEIGHT_CFLAGS
254 string
255 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
256 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
257
258 config ARCH_SUPPORTS_UPROBES
259 def_bool y
260
261 source "init/Kconfig"
262 source "kernel/Kconfig.freezer"
263
264 menu "Processor type and features"
265
266 config ZONE_DMA
267 bool "DMA memory allocation support" if EXPERT
268 default y
269 help
270 DMA memory allocation support allows devices with less than 32-bit
271 addressing to allocate within the first 16MB of address space.
272 Disable if no such devices will be used.
273
274 If unsure, say Y.
275
276 config SMP
277 bool "Symmetric multi-processing support"
278 ---help---
279 This enables support for systems with more than one CPU. If you have
280 a system with only one CPU, like most personal computers, say N. If
281 you have a system with more than one CPU, say Y.
282
283 If you say N here, the kernel will run on single and multiprocessor
284 machines, but will use only one CPU of a multiprocessor machine. If
285 you say Y here, the kernel will run on many, but not all,
286 singleprocessor machines. On a singleprocessor machine, the kernel
287 will run faster if you say N here.
288
289 Note that if you say Y here and choose architecture "586" or
290 "Pentium" under "Processor family", the kernel will not work on 486
291 architectures. Similarly, multiprocessor kernels for the "PPro"
292 architecture may not work on all Pentium based boards.
293
294 People using multiprocessor machines who say Y here should also say
295 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
296 Management" code will be disabled if you say Y here.
297
298 See also <file:Documentation/x86/i386/IO-APIC.txt>,
299 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
300 <http://www.tldp.org/docs.html#howto>.
301
302 If you don't know what to do here, say N.
303
304 config X86_X2APIC
305 bool "Support x2apic"
306 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
307 ---help---
308 This enables x2apic support on CPUs that have this feature.
309
310 This allows 32-bit apic IDs (so it can support very large systems),
311 and accesses the local apic via MSRs not via mmio.
312
313 If you don't know what to do here, say N.
314
315 config X86_MPPARSE
316 bool "Enable MPS table" if ACPI || SFI
317 default y
318 depends on X86_LOCAL_APIC
319 ---help---
320 For old smp systems that do not have proper acpi support. Newer systems
321 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
322
323 config X86_BIGSMP
324 bool "Support for big SMP systems with more than 8 CPUs"
325 depends on X86_32 && SMP
326 ---help---
327 This option is needed for the systems that have more than 8 CPUs
328
329 config GOLDFISH
330 def_bool y
331 depends on X86_GOLDFISH
332
333 if X86_32
334 config X86_EXTENDED_PLATFORM
335 bool "Support for extended (non-PC) x86 platforms"
336 default y
337 ---help---
338 If you disable this option then the kernel will only support
339 standard PC platforms. (which covers the vast majority of
340 systems out there.)
341
342 If you enable this option then you'll be able to select support
343 for the following (non-PC) 32 bit x86 platforms:
344 Goldfish (Android emulator)
345 AMD Elan
346 NUMAQ (IBM/Sequent)
347 RDC R-321x SoC
348 SGI 320/540 (Visual Workstation)
349 STA2X11-based (e.g. Northville)
350 Summit/EXA (IBM x440)
351 Unisys ES7000 IA32 series
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.
356 endif
357
358 if X86_64
359 config 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.
375 endif
376 # This is an alphabetically sorted list of 64 bit extended platforms
377 # Please maintain the alphabetic order if and when there are additions
378 config 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
391 config 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
403 config 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
416 config 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
425 config 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
440 config X86_WANT_INTEL_MID
441 bool "Intel MID platform support"
442 depends on X86_32
443 depends on X86_EXTENDED_PLATFORM
444 ---help---
445 Select to build a kernel capable of supporting Intel MID platform
446 systems which do not have the PCI legacy interfaces (Moorestown,
447 Medfield). If you are building for a PC class system say N here.
448
449 if X86_WANT_INTEL_MID
450
451 config X86_INTEL_MID
452 bool
453
454 config X86_MDFLD
455 bool "Medfield MID platform"
456 depends on PCI
457 depends on PCI_GOANY
458 depends on X86_IO_APIC
459 select X86_INTEL_MID
460 select SFI
461 select DW_APB_TIMER
462 select APB_TIMER
463 select I2C
464 select SPI
465 select INTEL_SCU_IPC
466 select X86_PLATFORM_DEVICES
467 select MFD_INTEL_MSIC
468 ---help---
469 Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin
470 Internet Device(MID) platform.
471 Unlike standard x86 PCs, Medfield does not have many legacy devices
472 nor standard legacy replacement devices/features. e.g. Medfield does
473 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
474
475 endif
476
477 config X86_INTEL_LPSS
478 bool "Intel Low Power Subsystem Support"
479 depends on ACPI
480 select COMMON_CLK
481 select PINCTRL
482 ---help---
483 Select to build support for Intel Low Power Subsystem such as
484 found on Intel Lynxpoint PCH. Selecting this option enables
485 things like clock tree (common clock framework) and pincontrol
486 which are needed by the LPSS peripheral drivers.
487
488 config X86_RDC321X
489 bool "RDC R-321x SoC"
490 depends on X86_32
491 depends on X86_EXTENDED_PLATFORM
492 select M486
493 select X86_REBOOTFIXUPS
494 ---help---
495 This option is needed for RDC R-321x system-on-chip, also known
496 as R-8610-(G).
497 If you don't have one of these chips, you should say N here.
498
499 config X86_32_NON_STANDARD
500 bool "Support non-standard 32-bit SMP architectures"
501 depends on X86_32 && SMP
502 depends on X86_EXTENDED_PLATFORM
503 ---help---
504 This option compiles in the NUMAQ, Summit, bigsmp, ES7000,
505 STA2X11, default subarchitectures. It is intended for a generic
506 binary kernel. If you select them all, kernel will probe it
507 one by one and will fallback to default.
508
509 # Alphabetically sorted list of Non standard 32 bit platforms
510
511 config X86_NUMAQ
512 bool "NUMAQ (IBM/Sequent)"
513 depends on X86_32_NON_STANDARD
514 depends on PCI
515 select NUMA
516 select X86_MPPARSE
517 ---help---
518 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
519 NUMA multiquad box. This changes the way that processors are
520 bootstrapped, and uses Clustered Logical APIC addressing mode instead
521 of Flat Logical. You will need a new lynxer.elf file to flash your
522 firmware with - send email to <Martin.Bligh@us.ibm.com>.
523
524 config X86_SUPPORTS_MEMORY_FAILURE
525 def_bool y
526 # MCE code calls memory_failure():
527 depends on X86_MCE
528 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
529 depends on !X86_NUMAQ
530 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
531 depends on X86_64 || !SPARSEMEM
532 select ARCH_SUPPORTS_MEMORY_FAILURE
533
534 config X86_VISWS
535 bool "SGI 320/540 (Visual Workstation)"
536 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
537 depends on X86_32_NON_STANDARD
538 ---help---
539 The SGI Visual Workstation series is an IA32-based workstation
540 based on SGI systems chips with some legacy PC hardware attached.
541
542 Say Y here to create a kernel to run on the SGI 320 or 540.
543
544 A kernel compiled for the Visual Workstation will run on general
545 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
546
547 config STA2X11
548 bool "STA2X11 Companion Chip Support"
549 depends on X86_32_NON_STANDARD && PCI
550 select X86_DEV_DMA_OPS
551 select X86_DMA_REMAP
552 select SWIOTLB
553 select MFD_STA2X11
554 select ARCH_REQUIRE_GPIOLIB
555 default n
556 ---help---
557 This adds support for boards based on the STA2X11 IO-Hub,
558 a.k.a. "ConneXt". The chip is used in place of the standard
559 PC chipset, so all "standard" peripherals are missing. If this
560 option is selected the kernel will still be able to boot on
561 standard PC machines.
562
563 config X86_SUMMIT
564 bool "Summit/EXA (IBM x440)"
565 depends on X86_32_NON_STANDARD
566 ---help---
567 This option is needed for IBM systems that use the Summit/EXA chipset.
568 In particular, it is needed for the x440.
569
570 config X86_ES7000
571 bool "Unisys ES7000 IA32 series"
572 depends on X86_32_NON_STANDARD && X86_BIGSMP
573 ---help---
574 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
575 supposed to run on an IA32-based Unisys ES7000 system.
576
577 config X86_32_IRIS
578 tristate "Eurobraille/Iris poweroff module"
579 depends on X86_32
580 ---help---
581 The Iris machines from EuroBraille do not have APM or ACPI support
582 to shut themselves down properly. A special I/O sequence is
583 needed to do so, which is what this module does at
584 kernel shutdown.
585
586 This is only for Iris machines from EuroBraille.
587
588 If unused, say N.
589
590 config SCHED_OMIT_FRAME_POINTER
591 def_bool y
592 prompt "Single-depth WCHAN output"
593 depends on X86
594 ---help---
595 Calculate simpler /proc/<PID>/wchan values. If this option
596 is disabled then wchan values will recurse back to the
597 caller function. This provides more accurate wchan values,
598 at the expense of slightly more scheduling overhead.
599
600 If in doubt, say "Y".
601
602 menuconfig HYPERVISOR_GUEST
603 bool "Linux guest support"
604 ---help---
605 Say Y here to enable options for running Linux under various hyper-
606 visors. This option enables basic hypervisor detection and platform
607 setup.
608
609 If you say N, all options in this submenu will be skipped and
610 disabled, and Linux guest support won't be built in.
611
612 if HYPERVISOR_GUEST
613
614 config PARAVIRT
615 bool "Enable paravirtualization code"
616 ---help---
617 This changes the kernel so it can modify itself when it is run
618 under a hypervisor, potentially improving performance significantly
619 over full virtualization. However, when run without a hypervisor
620 the kernel is theoretically slower and slightly larger.
621
622 config PARAVIRT_DEBUG
623 bool "paravirt-ops debugging"
624 depends on PARAVIRT && DEBUG_KERNEL
625 ---help---
626 Enable to debug paravirt_ops internals. Specifically, BUG if
627 a paravirt_op is missing when it is called.
628
629 config PARAVIRT_SPINLOCKS
630 bool "Paravirtualization layer for spinlocks"
631 depends on PARAVIRT && SMP
632 select UNINLINE_SPIN_UNLOCK
633 ---help---
634 Paravirtualized spinlocks allow a pvops backend to replace the
635 spinlock implementation with something virtualization-friendly
636 (for example, block the virtual CPU rather than spinning).
637
638 It has a minimal impact on native kernels and gives a nice performance
639 benefit on paravirtualized KVM / Xen kernels.
640
641 If you are unsure how to answer this question, answer Y.
642
643 source "arch/x86/xen/Kconfig"
644
645 config KVM_GUEST
646 bool "KVM Guest support (including kvmclock)"
647 depends on PARAVIRT
648 select PARAVIRT_CLOCK
649 default y
650 ---help---
651 This option enables various optimizations for running under the KVM
652 hypervisor. It includes a paravirtualized clock, so that instead
653 of relying on a PIT (or probably other) emulation by the
654 underlying device model, the host provides the guest with
655 timing infrastructure such as time of day, and system time
656
657 config KVM_DEBUG_FS
658 bool "Enable debug information for KVM Guests in debugfs"
659 depends on KVM_GUEST && DEBUG_FS
660 default n
661 ---help---
662 This option enables collection of various statistics for KVM guest.
663 Statistics are displayed in debugfs filesystem. Enabling this option
664 may incur significant overhead.
665
666 source "arch/x86/lguest/Kconfig"
667
668 config PARAVIRT_TIME_ACCOUNTING
669 bool "Paravirtual steal time accounting"
670 depends on PARAVIRT
671 default n
672 ---help---
673 Select this option to enable fine granularity task steal time
674 accounting. Time spent executing other tasks in parallel with
675 the current vCPU is discounted from the vCPU power. To account for
676 that, there can be a small performance impact.
677
678 If in doubt, say N here.
679
680 config PARAVIRT_CLOCK
681 bool
682
683 endif #HYPERVISOR_GUEST
684
685 config NO_BOOTMEM
686 def_bool y
687
688 config MEMTEST
689 bool "Memtest"
690 ---help---
691 This option adds a kernel parameter 'memtest', which allows memtest
692 to be set.
693 memtest=0, mean disabled; -- default
694 memtest=1, mean do 1 test pattern;
695 ...
696 memtest=4, mean do 4 test patterns.
697 If you are unsure how to answer this question, answer N.
698
699 config X86_SUMMIT_NUMA
700 def_bool y
701 depends on X86_32 && NUMA && X86_32_NON_STANDARD
702
703 config X86_CYCLONE_TIMER
704 def_bool y
705 depends on X86_SUMMIT
706
707 source "arch/x86/Kconfig.cpu"
708
709 config HPET_TIMER
710 def_bool X86_64
711 prompt "HPET Timer Support" if X86_32
712 ---help---
713 Use the IA-PC HPET (High Precision Event Timer) to manage
714 time in preference to the PIT and RTC, if a HPET is
715 present.
716 HPET is the next generation timer replacing legacy 8254s.
717 The HPET provides a stable time base on SMP
718 systems, unlike the TSC, but it is more expensive to access,
719 as it is off-chip. You can find the HPET spec at
720 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
721
722 You can safely choose Y here. However, HPET will only be
723 activated if the platform and the BIOS support this feature.
724 Otherwise the 8254 will be used for timing services.
725
726 Choose N to continue using the legacy 8254 timer.
727
728 config HPET_EMULATE_RTC
729 def_bool y
730 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
731
732 config APB_TIMER
733 def_bool y if X86_INTEL_MID
734 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
735 select DW_APB_TIMER
736 depends on X86_INTEL_MID && SFI
737 help
738 APB timer is the replacement for 8254, HPET on X86 MID platforms.
739 The APBT provides a stable time base on SMP
740 systems, unlike the TSC, but it is more expensive to access,
741 as it is off-chip. APB timers are always running regardless of CPU
742 C states, they are used as per CPU clockevent device when possible.
743
744 # Mark as expert because too many people got it wrong.
745 # The code disables itself when not needed.
746 config DMI
747 default y
748 bool "Enable DMI scanning" if EXPERT
749 ---help---
750 Enabled scanning of DMI to identify machine quirks. Say Y
751 here unless you have verified that your setup is not
752 affected by entries in the DMI blacklist. Required by PNP
753 BIOS code.
754
755 config GART_IOMMU
756 bool "Old AMD GART IOMMU support"
757 select SWIOTLB
758 depends on X86_64 && PCI && AMD_NB
759 ---help---
760 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
761 GART based hardware IOMMUs.
762
763 The GART supports full DMA access for devices with 32-bit access
764 limitations, on systems with more than 3 GB. This is usually needed
765 for USB, sound, many IDE/SATA chipsets and some other devices.
766
767 Newer systems typically have a modern AMD IOMMU, supported via
768 the CONFIG_AMD_IOMMU=y config option.
769
770 In normal configurations this driver is only active when needed:
771 there's more than 3 GB of memory and the system contains a
772 32-bit limited device.
773
774 If unsure, say Y.
775
776 config CALGARY_IOMMU
777 bool "IBM Calgary IOMMU support"
778 select SWIOTLB
779 depends on X86_64 && PCI
780 ---help---
781 Support for hardware IOMMUs in IBM's xSeries x366 and x460
782 systems. Needed to run systems with more than 3GB of memory
783 properly with 32-bit PCI devices that do not support DAC
784 (Double Address Cycle). Calgary also supports bus level
785 isolation, where all DMAs pass through the IOMMU. This
786 prevents them from going anywhere except their intended
787 destination. This catches hard-to-find kernel bugs and
788 mis-behaving drivers and devices that do not use the DMA-API
789 properly to set up their DMA buffers. The IOMMU can be
790 turned off at boot time with the iommu=off parameter.
791 Normally the kernel will make the right choice by itself.
792 If unsure, say Y.
793
794 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
795 def_bool y
796 prompt "Should Calgary be enabled by default?"
797 depends on CALGARY_IOMMU
798 ---help---
799 Should Calgary be enabled by default? if you choose 'y', Calgary
800 will be used (if it exists). If you choose 'n', Calgary will not be
801 used even if it exists. If you choose 'n' and would like to use
802 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
803 If unsure, say Y.
804
805 # need this always selected by IOMMU for the VIA workaround
806 config SWIOTLB
807 def_bool y if X86_64
808 ---help---
809 Support for software bounce buffers used on x86-64 systems
810 which don't have a hardware IOMMU. Using this PCI devices
811 which can only access 32-bits of memory can be used on systems
812 with more than 3 GB of memory.
813 If unsure, say Y.
814
815 config IOMMU_HELPER
816 def_bool y
817 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
818
819 config MAXSMP
820 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
821 depends on X86_64 && SMP && DEBUG_KERNEL
822 select CPUMASK_OFFSTACK
823 ---help---
824 Enable maximum number of CPUS and NUMA Nodes for this architecture.
825 If unsure, say N.
826
827 config NR_CPUS
828 int "Maximum number of CPUs" if SMP && !MAXSMP
829 range 2 8 if SMP && X86_32 && !X86_BIGSMP
830 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
831 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
832 default "1" if !SMP
833 default "8192" if MAXSMP
834 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
835 default "8" if SMP
836 ---help---
837 This allows you to specify the maximum number of CPUs which this
838 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
839 supported value is 4096, otherwise the maximum value is 512. The
840 minimum value which makes sense is 2.
841
842 This is purely to save memory - each supported CPU adds
843 approximately eight kilobytes to the kernel image.
844
845 config SCHED_SMT
846 bool "SMT (Hyperthreading) scheduler support"
847 depends on X86_HT
848 ---help---
849 SMT scheduler support improves the CPU scheduler's decision making
850 when dealing with Intel Pentium 4 chips with HyperThreading at a
851 cost of slightly increased overhead in some places. If unsure say
852 N here.
853
854 config SCHED_MC
855 def_bool y
856 prompt "Multi-core scheduler support"
857 depends on X86_HT
858 ---help---
859 Multi-core scheduler support improves the CPU scheduler's decision
860 making when dealing with multi-core CPU chips at a cost of slightly
861 increased overhead in some places. If unsure say N here.
862
863 source "kernel/Kconfig.preempt"
864
865 config X86_UP_APIC
866 bool "Local APIC support on uniprocessors"
867 depends on X86_32 && !SMP && !X86_32_NON_STANDARD && !PCI_MSI
868 ---help---
869 A local APIC (Advanced Programmable Interrupt Controller) is an
870 integrated interrupt controller in the CPU. If you have a single-CPU
871 system which has a processor with a local APIC, you can say Y here to
872 enable and use it. If you say Y here even though your machine doesn't
873 have a local APIC, then the kernel will still run with no slowdown at
874 all. The local APIC supports CPU-generated self-interrupts (timer,
875 performance counters), and the NMI watchdog which detects hard
876 lockups.
877
878 config X86_UP_IOAPIC
879 bool "IO-APIC support on uniprocessors"
880 depends on X86_UP_APIC
881 ---help---
882 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
883 SMP-capable replacement for PC-style interrupt controllers. Most
884 SMP systems and many recent uniprocessor systems have one.
885
886 If you have a single-CPU system with an IO-APIC, you can say Y here
887 to use it. If you say Y here even though your machine doesn't have
888 an IO-APIC, then the kernel will still run with no slowdown at all.
889
890 config X86_LOCAL_APIC
891 def_bool y
892 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
893
894 config X86_IO_APIC
895 def_bool y
896 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC || PCI_MSI
897
898 config X86_VISWS_APIC
899 def_bool y
900 depends on X86_32 && X86_VISWS
901
902 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
903 bool "Reroute for broken boot IRQs"
904 depends on X86_IO_APIC
905 ---help---
906 This option enables a workaround that fixes a source of
907 spurious interrupts. This is recommended when threaded
908 interrupt handling is used on systems where the generation of
909 superfluous "boot interrupts" cannot be disabled.
910
911 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
912 entry in the chipset's IO-APIC is masked (as, e.g. the RT
913 kernel does during interrupt handling). On chipsets where this
914 boot IRQ generation cannot be disabled, this workaround keeps
915 the original IRQ line masked so that only the equivalent "boot
916 IRQ" is delivered to the CPUs. The workaround also tells the
917 kernel to set up the IRQ handler on the boot IRQ line. In this
918 way only one interrupt is delivered to the kernel. Otherwise
919 the spurious second interrupt may cause the kernel to bring
920 down (vital) interrupt lines.
921
922 Only affects "broken" chipsets. Interrupt sharing may be
923 increased on these systems.
924
925 config X86_MCE
926 bool "Machine Check / overheating reporting"
927 default y
928 ---help---
929 Machine Check support allows the processor to notify the
930 kernel if it detects a problem (e.g. overheating, data corruption).
931 The action the kernel takes depends on the severity of the problem,
932 ranging from warning messages to halting the machine.
933
934 config X86_MCE_INTEL
935 def_bool y
936 prompt "Intel MCE features"
937 depends on X86_MCE && X86_LOCAL_APIC
938 ---help---
939 Additional support for intel specific MCE features such as
940 the thermal monitor.
941
942 config X86_MCE_AMD
943 def_bool y
944 prompt "AMD MCE features"
945 depends on X86_MCE && X86_LOCAL_APIC
946 ---help---
947 Additional support for AMD specific MCE features such as
948 the DRAM Error Threshold.
949
950 config X86_ANCIENT_MCE
951 bool "Support for old Pentium 5 / WinChip machine checks"
952 depends on X86_32 && X86_MCE
953 ---help---
954 Include support for machine check handling on old Pentium 5 or WinChip
955 systems. These typically need to be enabled explicitly on the command
956 line.
957
958 config X86_MCE_THRESHOLD
959 depends on X86_MCE_AMD || X86_MCE_INTEL
960 def_bool y
961
962 config X86_MCE_INJECT
963 depends on X86_MCE
964 tristate "Machine check injector support"
965 ---help---
966 Provide support for injecting machine checks for testing purposes.
967 If you don't know what a machine check is and you don't do kernel
968 QA it is safe to say n.
969
970 config X86_THERMAL_VECTOR
971 def_bool y
972 depends on X86_MCE_INTEL
973
974 config VM86
975 bool "Enable VM86 support" if EXPERT
976 default y
977 depends on X86_32
978 ---help---
979 This option is required by programs like DOSEMU to run 16-bit legacy
980 code on X86 processors. It also may be needed by software like
981 XFree86 to initialize some video cards via BIOS. Disabling this
982 option saves about 6k.
983
984 config TOSHIBA
985 tristate "Toshiba Laptop support"
986 depends on X86_32
987 ---help---
988 This adds a driver to safely access the System Management Mode of
989 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
990 not work on models with a Phoenix BIOS. The System Management Mode
991 is used to set the BIOS and power saving options on Toshiba portables.
992
993 For information on utilities to make use of this driver see the
994 Toshiba Linux utilities web site at:
995 <http://www.buzzard.org.uk/toshiba/>.
996
997 Say Y if you intend to run this kernel on a Toshiba portable.
998 Say N otherwise.
999
1000 config I8K
1001 tristate "Dell laptop support"
1002 select HWMON
1003 ---help---
1004 This adds a driver to safely access the System Management Mode
1005 of the CPU on the Dell Inspiron 8000. The System Management Mode
1006 is used to read cpu temperature and cooling fan status and to
1007 control the fans on the I8K portables.
1008
1009 This driver has been tested only on the Inspiron 8000 but it may
1010 also work with other Dell laptops. You can force loading on other
1011 models by passing the parameter `force=1' to the module. Use at
1012 your own risk.
1013
1014 For information on utilities to make use of this driver see the
1015 I8K Linux utilities web site at:
1016 <http://people.debian.org/~dz/i8k/>
1017
1018 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
1019 Say N otherwise.
1020
1021 config X86_REBOOTFIXUPS
1022 bool "Enable X86 board specific fixups for reboot"
1023 depends on X86_32
1024 ---help---
1025 This enables chipset and/or board specific fixups to be done
1026 in order to get reboot to work correctly. This is only needed on
1027 some combinations of hardware and BIOS. The symptom, for which
1028 this config is intended, is when reboot ends with a stalled/hung
1029 system.
1030
1031 Currently, the only fixup is for the Geode machines using
1032 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1033
1034 Say Y if you want to enable the fixup. Currently, it's safe to
1035 enable this option even if you don't need it.
1036 Say N otherwise.
1037
1038 config MICROCODE
1039 tristate "CPU microcode loading support"
1040 depends on CPU_SUP_AMD || CPU_SUP_INTEL
1041 select FW_LOADER
1042 ---help---
1043
1044 If you say Y here, you will be able to update the microcode on
1045 certain Intel and AMD processors. The Intel support is for the
1046 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1047 Xeon etc. The AMD support is for families 0x10 and later. You will
1048 obviously need the actual microcode binary data itself which is not
1049 shipped with the Linux kernel.
1050
1051 This option selects the general module only, you need to select
1052 at least one vendor specific module as well.
1053
1054 To compile this driver as a module, choose M here: the module
1055 will be called microcode.
1056
1057 config MICROCODE_INTEL
1058 bool "Intel microcode loading support"
1059 depends on MICROCODE
1060 default MICROCODE
1061 select FW_LOADER
1062 ---help---
1063 This options enables microcode patch loading support for Intel
1064 processors.
1065
1066 For latest news and information on obtaining all the required
1067 Intel ingredients for this driver, check:
1068 <http://www.urbanmyth.org/microcode/>.
1069
1070 config MICROCODE_AMD
1071 bool "AMD microcode loading support"
1072 depends on MICROCODE
1073 select FW_LOADER
1074 ---help---
1075 If you select this option, microcode patch loading support for AMD
1076 processors will be enabled.
1077
1078 config MICROCODE_OLD_INTERFACE
1079 def_bool y
1080 depends on MICROCODE
1081
1082 config MICROCODE_INTEL_LIB
1083 def_bool y
1084 depends on MICROCODE_INTEL
1085
1086 config MICROCODE_INTEL_EARLY
1087 def_bool n
1088
1089 config MICROCODE_AMD_EARLY
1090 def_bool n
1091
1092 config MICROCODE_EARLY
1093 bool "Early load microcode"
1094 depends on MICROCODE=y && BLK_DEV_INITRD
1095 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL
1096 select MICROCODE_AMD_EARLY if MICROCODE_AMD
1097 default y
1098 help
1099 This option provides functionality to read additional microcode data
1100 at the beginning of initrd image. The data tells kernel to load
1101 microcode to CPU's as early as possible. No functional change if no
1102 microcode data is glued to the initrd, therefore it's safe to say Y.
1103
1104 config X86_MSR
1105 tristate "/dev/cpu/*/msr - Model-specific register support"
1106 ---help---
1107 This device gives privileged processes access to the x86
1108 Model-Specific Registers (MSRs). It is a character device with
1109 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1110 MSR accesses are directed to a specific CPU on multi-processor
1111 systems.
1112
1113 config X86_CPUID
1114 tristate "/dev/cpu/*/cpuid - CPU information support"
1115 ---help---
1116 This device gives processes access to the x86 CPUID instruction to
1117 be executed on a specific processor. It is a character device
1118 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1119 /dev/cpu/31/cpuid.
1120
1121 choice
1122 prompt "High Memory Support"
1123 default HIGHMEM64G if X86_NUMAQ
1124 default HIGHMEM4G
1125 depends on X86_32
1126
1127 config NOHIGHMEM
1128 bool "off"
1129 depends on !X86_NUMAQ
1130 ---help---
1131 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1132 However, the address space of 32-bit x86 processors is only 4
1133 Gigabytes large. That means that, if you have a large amount of
1134 physical memory, not all of it can be "permanently mapped" by the
1135 kernel. The physical memory that's not permanently mapped is called
1136 "high memory".
1137
1138 If you are compiling a kernel which will never run on a machine with
1139 more than 1 Gigabyte total physical RAM, answer "off" here (default
1140 choice and suitable for most users). This will result in a "3GB/1GB"
1141 split: 3GB are mapped so that each process sees a 3GB virtual memory
1142 space and the remaining part of the 4GB virtual memory space is used
1143 by the kernel to permanently map as much physical memory as
1144 possible.
1145
1146 If the machine has between 1 and 4 Gigabytes physical RAM, then
1147 answer "4GB" here.
1148
1149 If more than 4 Gigabytes is used then answer "64GB" here. This
1150 selection turns Intel PAE (Physical Address Extension) mode on.
1151 PAE implements 3-level paging on IA32 processors. PAE is fully
1152 supported by Linux, PAE mode is implemented on all recent Intel
1153 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1154 then the kernel will not boot on CPUs that don't support PAE!
1155
1156 The actual amount of total physical memory will either be
1157 auto detected or can be forced by using a kernel command line option
1158 such as "mem=256M". (Try "man bootparam" or see the documentation of
1159 your boot loader (lilo or loadlin) about how to pass options to the
1160 kernel at boot time.)
1161
1162 If unsure, say "off".
1163
1164 config HIGHMEM4G
1165 bool "4GB"
1166 depends on !X86_NUMAQ
1167 ---help---
1168 Select this if you have a 32-bit processor and between 1 and 4
1169 gigabytes of physical RAM.
1170
1171 config HIGHMEM64G
1172 bool "64GB"
1173 depends on !M486
1174 select X86_PAE
1175 ---help---
1176 Select this if you have a 32-bit processor and more than 4
1177 gigabytes of physical RAM.
1178
1179 endchoice
1180
1181 choice
1182 prompt "Memory split" if EXPERT
1183 default VMSPLIT_3G
1184 depends on X86_32
1185 ---help---
1186 Select the desired split between kernel and user memory.
1187
1188 If the address range available to the kernel is less than the
1189 physical memory installed, the remaining memory will be available
1190 as "high memory". Accessing high memory is a little more costly
1191 than low memory, as it needs to be mapped into the kernel first.
1192 Note that increasing the kernel address space limits the range
1193 available to user programs, making the address space there
1194 tighter. Selecting anything other than the default 3G/1G split
1195 will also likely make your kernel incompatible with binary-only
1196 kernel modules.
1197
1198 If you are not absolutely sure what you are doing, leave this
1199 option alone!
1200
1201 config VMSPLIT_3G
1202 bool "3G/1G user/kernel split"
1203 config VMSPLIT_3G_OPT
1204 depends on !X86_PAE
1205 bool "3G/1G user/kernel split (for full 1G low memory)"
1206 config VMSPLIT_2G
1207 bool "2G/2G user/kernel split"
1208 config VMSPLIT_2G_OPT
1209 depends on !X86_PAE
1210 bool "2G/2G user/kernel split (for full 2G low memory)"
1211 config VMSPLIT_1G
1212 bool "1G/3G user/kernel split"
1213 endchoice
1214
1215 config PAGE_OFFSET
1216 hex
1217 default 0xB0000000 if VMSPLIT_3G_OPT
1218 default 0x80000000 if VMSPLIT_2G
1219 default 0x78000000 if VMSPLIT_2G_OPT
1220 default 0x40000000 if VMSPLIT_1G
1221 default 0xC0000000
1222 depends on X86_32
1223
1224 config HIGHMEM
1225 def_bool y
1226 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1227
1228 config X86_PAE
1229 bool "PAE (Physical Address Extension) Support"
1230 depends on X86_32 && !HIGHMEM4G
1231 ---help---
1232 PAE is required for NX support, and furthermore enables
1233 larger swapspace support for non-overcommit purposes. It
1234 has the cost of more pagetable lookup overhead, and also
1235 consumes more pagetable space per process.
1236
1237 config ARCH_PHYS_ADDR_T_64BIT
1238 def_bool y
1239 depends on X86_64 || X86_PAE
1240
1241 config ARCH_DMA_ADDR_T_64BIT
1242 def_bool y
1243 depends on X86_64 || HIGHMEM64G
1244
1245 config DIRECT_GBPAGES
1246 bool "Enable 1GB pages for kernel pagetables" if EXPERT
1247 default y
1248 depends on X86_64
1249 ---help---
1250 Allow the kernel linear mapping to use 1GB pages on CPUs that
1251 support it. This can improve the kernel's performance a tiny bit by
1252 reducing TLB pressure. If in doubt, say "Y".
1253
1254 # Common NUMA Features
1255 config NUMA
1256 bool "Numa Memory Allocation and Scheduler Support"
1257 depends on SMP
1258 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI))
1259 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1260 ---help---
1261 Enable NUMA (Non Uniform Memory Access) support.
1262
1263 The kernel will try to allocate memory used by a CPU on the
1264 local memory controller of the CPU and add some more
1265 NUMA awareness to the kernel.
1266
1267 For 64-bit this is recommended if the system is Intel Core i7
1268 (or later), AMD Opteron, or EM64T NUMA.
1269
1270 For 32-bit this is only needed on (rare) 32-bit-only platforms
1271 that support NUMA topologies, such as NUMAQ / Summit, or if you
1272 boot a 32-bit kernel on a 64-bit NUMA platform.
1273
1274 Otherwise, you should say N.
1275
1276 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1277 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1278
1279 config AMD_NUMA
1280 def_bool y
1281 prompt "Old style AMD Opteron NUMA detection"
1282 depends on X86_64 && NUMA && PCI
1283 ---help---
1284 Enable AMD NUMA node topology detection. You should say Y here if
1285 you have a multi processor AMD system. This uses an old method to
1286 read the NUMA configuration directly from the builtin Northbridge
1287 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1288 which also takes priority if both are compiled in.
1289
1290 config X86_64_ACPI_NUMA
1291 def_bool y
1292 prompt "ACPI NUMA detection"
1293 depends on X86_64 && NUMA && ACPI && PCI
1294 select ACPI_NUMA
1295 ---help---
1296 Enable ACPI SRAT based node topology detection.
1297
1298 # Some NUMA nodes have memory ranges that span
1299 # other nodes. Even though a pfn is valid and
1300 # between a node's start and end pfns, it may not
1301 # reside on that node. See memmap_init_zone()
1302 # for details.
1303 config NODES_SPAN_OTHER_NODES
1304 def_bool y
1305 depends on X86_64_ACPI_NUMA
1306
1307 config NUMA_EMU
1308 bool "NUMA emulation"
1309 depends on NUMA
1310 ---help---
1311 Enable NUMA emulation. A flat machine will be split
1312 into virtual nodes when booted with "numa=fake=N", where N is the
1313 number of nodes. This is only useful for debugging.
1314
1315 config NODES_SHIFT
1316 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1317 range 1 10
1318 default "10" if MAXSMP
1319 default "6" if X86_64
1320 default "4" if X86_NUMAQ
1321 default "3"
1322 depends on NEED_MULTIPLE_NODES
1323 ---help---
1324 Specify the maximum number of NUMA Nodes available on the target
1325 system. Increases memory reserved to accommodate various tables.
1326
1327 config ARCH_HAVE_MEMORY_PRESENT
1328 def_bool y
1329 depends on X86_32 && DISCONTIGMEM
1330
1331 config NEED_NODE_MEMMAP_SIZE
1332 def_bool y
1333 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1334
1335 config ARCH_FLATMEM_ENABLE
1336 def_bool y
1337 depends on X86_32 && !NUMA
1338
1339 config ARCH_DISCONTIGMEM_ENABLE
1340 def_bool y
1341 depends on NUMA && X86_32
1342
1343 config ARCH_DISCONTIGMEM_DEFAULT
1344 def_bool y
1345 depends on NUMA && X86_32
1346
1347 config ARCH_SPARSEMEM_ENABLE
1348 def_bool y
1349 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1350 select SPARSEMEM_STATIC if X86_32
1351 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1352
1353 config ARCH_SPARSEMEM_DEFAULT
1354 def_bool y
1355 depends on X86_64
1356
1357 config ARCH_SELECT_MEMORY_MODEL
1358 def_bool y
1359 depends on ARCH_SPARSEMEM_ENABLE
1360
1361 config ARCH_MEMORY_PROBE
1362 bool "Enable sysfs memory/probe interface"
1363 depends on X86_64 && MEMORY_HOTPLUG
1364 help
1365 This option enables a sysfs memory/probe interface for testing.
1366 See Documentation/memory-hotplug.txt for more information.
1367 If you are unsure how to answer this question, answer N.
1368
1369 config ARCH_PROC_KCORE_TEXT
1370 def_bool y
1371 depends on X86_64 && PROC_KCORE
1372
1373 config ILLEGAL_POINTER_VALUE
1374 hex
1375 default 0 if X86_32
1376 default 0xdead000000000000 if X86_64
1377
1378 source "mm/Kconfig"
1379
1380 config HIGHPTE
1381 bool "Allocate 3rd-level pagetables from highmem"
1382 depends on HIGHMEM
1383 ---help---
1384 The VM uses one page table entry for each page of physical memory.
1385 For systems with a lot of RAM, this can be wasteful of precious
1386 low memory. Setting this option will put user-space page table
1387 entries in high memory.
1388
1389 config X86_CHECK_BIOS_CORRUPTION
1390 bool "Check for low memory corruption"
1391 ---help---
1392 Periodically check for memory corruption in low memory, which
1393 is suspected to be caused by BIOS. Even when enabled in the
1394 configuration, it is disabled at runtime. Enable it by
1395 setting "memory_corruption_check=1" on the kernel command
1396 line. By default it scans the low 64k of memory every 60
1397 seconds; see the memory_corruption_check_size and
1398 memory_corruption_check_period parameters in
1399 Documentation/kernel-parameters.txt to adjust this.
1400
1401 When enabled with the default parameters, this option has
1402 almost no overhead, as it reserves a relatively small amount
1403 of memory and scans it infrequently. It both detects corruption
1404 and prevents it from affecting the running system.
1405
1406 It is, however, intended as a diagnostic tool; if repeatable
1407 BIOS-originated corruption always affects the same memory,
1408 you can use memmap= to prevent the kernel from using that
1409 memory.
1410
1411 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1412 bool "Set the default setting of memory_corruption_check"
1413 depends on X86_CHECK_BIOS_CORRUPTION
1414 default y
1415 ---help---
1416 Set whether the default state of memory_corruption_check is
1417 on or off.
1418
1419 config X86_RESERVE_LOW
1420 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1421 default 64
1422 range 4 640
1423 ---help---
1424 Specify the amount of low memory to reserve for the BIOS.
1425
1426 The first page contains BIOS data structures that the kernel
1427 must not use, so that page must always be reserved.
1428
1429 By default we reserve the first 64K of physical RAM, as a
1430 number of BIOSes are known to corrupt that memory range
1431 during events such as suspend/resume or monitor cable
1432 insertion, so it must not be used by the kernel.
1433
1434 You can set this to 4 if you are absolutely sure that you
1435 trust the BIOS to get all its memory reservations and usages
1436 right. If you know your BIOS have problems beyond the
1437 default 64K area, you can set this to 640 to avoid using the
1438 entire low memory range.
1439
1440 If you have doubts about the BIOS (e.g. suspend/resume does
1441 not work or there's kernel crashes after certain hardware
1442 hotplug events) then you might want to enable
1443 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1444 typical corruption patterns.
1445
1446 Leave this to the default value of 64 if you are unsure.
1447
1448 config MATH_EMULATION
1449 bool
1450 prompt "Math emulation" if X86_32
1451 ---help---
1452 Linux can emulate a math coprocessor (used for floating point
1453 operations) if you don't have one. 486DX and Pentium processors have
1454 a math coprocessor built in, 486SX and 386 do not, unless you added
1455 a 487DX or 387, respectively. (The messages during boot time can
1456 give you some hints here ["man dmesg"].) Everyone needs either a
1457 coprocessor or this emulation.
1458
1459 If you don't have a math coprocessor, you need to say Y here; if you
1460 say Y here even though you have a coprocessor, the coprocessor will
1461 be used nevertheless. (This behavior can be changed with the kernel
1462 command line option "no387", which comes handy if your coprocessor
1463 is broken. Try "man bootparam" or see the documentation of your boot
1464 loader (lilo or loadlin) about how to pass options to the kernel at
1465 boot time.) This means that it is a good idea to say Y here if you
1466 intend to use this kernel on different machines.
1467
1468 More information about the internals of the Linux math coprocessor
1469 emulation can be found in <file:arch/x86/math-emu/README>.
1470
1471 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1472 kernel, it won't hurt.
1473
1474 config MTRR
1475 def_bool y
1476 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1477 ---help---
1478 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1479 the Memory Type Range Registers (MTRRs) may be used to control
1480 processor access to memory ranges. This is most useful if you have
1481 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1482 allows bus write transfers to be combined into a larger transfer
1483 before bursting over the PCI/AGP bus. This can increase performance
1484 of image write operations 2.5 times or more. Saying Y here creates a
1485 /proc/mtrr file which may be used to manipulate your processor's
1486 MTRRs. Typically the X server should use this.
1487
1488 This code has a reasonably generic interface so that similar
1489 control registers on other processors can be easily supported
1490 as well:
1491
1492 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1493 Registers (ARRs) which provide a similar functionality to MTRRs. For
1494 these, the ARRs are used to emulate the MTRRs.
1495 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1496 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1497 write-combining. All of these processors are supported by this code
1498 and it makes sense to say Y here if you have one of them.
1499
1500 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1501 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1502 can lead to all sorts of problems, so it's good to say Y here.
1503
1504 You can safely say Y even if your machine doesn't have MTRRs, you'll
1505 just add about 9 KB to your kernel.
1506
1507 See <file:Documentation/x86/mtrr.txt> for more information.
1508
1509 config MTRR_SANITIZER
1510 def_bool y
1511 prompt "MTRR cleanup support"
1512 depends on MTRR
1513 ---help---
1514 Convert MTRR layout from continuous to discrete, so X drivers can
1515 add writeback entries.
1516
1517 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1518 The largest mtrr entry size for a continuous block can be set with
1519 mtrr_chunk_size.
1520
1521 If unsure, say Y.
1522
1523 config MTRR_SANITIZER_ENABLE_DEFAULT
1524 int "MTRR cleanup enable value (0-1)"
1525 range 0 1
1526 default "0"
1527 depends on MTRR_SANITIZER
1528 ---help---
1529 Enable mtrr cleanup default value
1530
1531 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1532 int "MTRR cleanup spare reg num (0-7)"
1533 range 0 7
1534 default "1"
1535 depends on MTRR_SANITIZER
1536 ---help---
1537 mtrr cleanup spare entries default, it can be changed via
1538 mtrr_spare_reg_nr=N on the kernel command line.
1539
1540 config X86_PAT
1541 def_bool y
1542 prompt "x86 PAT support" if EXPERT
1543 depends on MTRR
1544 ---help---
1545 Use PAT attributes to setup page level cache control.
1546
1547 PATs are the modern equivalents of MTRRs and are much more
1548 flexible than MTRRs.
1549
1550 Say N here if you see bootup problems (boot crash, boot hang,
1551 spontaneous reboots) or a non-working video driver.
1552
1553 If unsure, say Y.
1554
1555 config ARCH_USES_PG_UNCACHED
1556 def_bool y
1557 depends on X86_PAT
1558
1559 config ARCH_RANDOM
1560 def_bool y
1561 prompt "x86 architectural random number generator" if EXPERT
1562 ---help---
1563 Enable the x86 architectural RDRAND instruction
1564 (Intel Bull Mountain technology) to generate random numbers.
1565 If supported, this is a high bandwidth, cryptographically
1566 secure hardware random number generator.
1567
1568 config X86_SMAP
1569 def_bool y
1570 prompt "Supervisor Mode Access Prevention" if EXPERT
1571 ---help---
1572 Supervisor Mode Access Prevention (SMAP) is a security
1573 feature in newer Intel processors. There is a small
1574 performance cost if this enabled and turned on; there is
1575 also a small increase in the kernel size if this is enabled.
1576
1577 If unsure, say Y.
1578
1579 config EFI
1580 bool "EFI runtime service support"
1581 depends on ACPI
1582 select UCS2_STRING
1583 ---help---
1584 This enables the kernel to use EFI runtime services that are
1585 available (such as the EFI variable services).
1586
1587 This option is only useful on systems that have EFI firmware.
1588 In addition, you should use the latest ELILO loader available
1589 at <http://elilo.sourceforge.net> in order to take advantage
1590 of EFI runtime services. However, even with this option, the
1591 resultant kernel should continue to boot on existing non-EFI
1592 platforms.
1593
1594 config EFI_STUB
1595 bool "EFI stub support"
1596 depends on EFI
1597 ---help---
1598 This kernel feature allows a bzImage to be loaded directly
1599 by EFI firmware without the use of a bootloader.
1600
1601 See Documentation/efi-stub.txt for more information.
1602
1603 config SECCOMP
1604 def_bool y
1605 prompt "Enable seccomp to safely compute untrusted bytecode"
1606 ---help---
1607 This kernel feature is useful for number crunching applications
1608 that may need to compute untrusted bytecode during their
1609 execution. By using pipes or other transports made available to
1610 the process as file descriptors supporting the read/write
1611 syscalls, it's possible to isolate those applications in
1612 their own address space using seccomp. Once seccomp is
1613 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1614 and the task is only allowed to execute a few safe syscalls
1615 defined by each seccomp mode.
1616
1617 If unsure, say Y. Only embedded should say N here.
1618
1619 config CC_STACKPROTECTOR
1620 bool "Enable -fstack-protector buffer overflow detection"
1621 ---help---
1622 This option turns on the -fstack-protector GCC feature. This
1623 feature puts, at the beginning of functions, a canary value on
1624 the stack just before the return address, and validates
1625 the value just before actually returning. Stack based buffer
1626 overflows (that need to overwrite this return address) now also
1627 overwrite the canary, which gets detected and the attack is then
1628 neutralized via a kernel panic.
1629
1630 This feature requires gcc version 4.2 or above, or a distribution
1631 gcc with the feature backported. Older versions are automatically
1632 detected and for those versions, this configuration option is
1633 ignored. (and a warning is printed during bootup)
1634
1635 source kernel/Kconfig.hz
1636
1637 config KEXEC
1638 bool "kexec system call"
1639 ---help---
1640 kexec is a system call that implements the ability to shutdown your
1641 current kernel, and to start another kernel. It is like a reboot
1642 but it is independent of the system firmware. And like a reboot
1643 you can start any kernel with it, not just Linux.
1644
1645 The name comes from the similarity to the exec system call.
1646
1647 It is an ongoing process to be certain the hardware in a machine
1648 is properly shutdown, so do not be surprised if this code does not
1649 initially work for you. As of this writing the exact hardware
1650 interface is strongly in flux, so no good recommendation can be
1651 made.
1652
1653 config CRASH_DUMP
1654 bool "kernel crash dumps"
1655 depends on X86_64 || (X86_32 && HIGHMEM)
1656 ---help---
1657 Generate crash dump after being started by kexec.
1658 This should be normally only set in special crash dump kernels
1659 which are loaded in the main kernel with kexec-tools into
1660 a specially reserved region and then later executed after
1661 a crash by kdump/kexec. The crash dump kernel must be compiled
1662 to a memory address not used by the main kernel or BIOS using
1663 PHYSICAL_START, or it must be built as a relocatable image
1664 (CONFIG_RELOCATABLE=y).
1665 For more details see Documentation/kdump/kdump.txt
1666
1667 config KEXEC_JUMP
1668 bool "kexec jump"
1669 depends on KEXEC && HIBERNATION
1670 ---help---
1671 Jump between original kernel and kexeced kernel and invoke
1672 code in physical address mode via KEXEC
1673
1674 config PHYSICAL_START
1675 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1676 default "0x1000000"
1677 ---help---
1678 This gives the physical address where the kernel is loaded.
1679
1680 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1681 bzImage will decompress itself to above physical address and
1682 run from there. Otherwise, bzImage will run from the address where
1683 it has been loaded by the boot loader and will ignore above physical
1684 address.
1685
1686 In normal kdump cases one does not have to set/change this option
1687 as now bzImage can be compiled as a completely relocatable image
1688 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1689 address. This option is mainly useful for the folks who don't want
1690 to use a bzImage for capturing the crash dump and want to use a
1691 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1692 to be specifically compiled to run from a specific memory area
1693 (normally a reserved region) and this option comes handy.
1694
1695 So if you are using bzImage for capturing the crash dump,
1696 leave the value here unchanged to 0x1000000 and set
1697 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1698 for capturing the crash dump change this value to start of
1699 the reserved region. In other words, it can be set based on
1700 the "X" value as specified in the "crashkernel=YM@XM"
1701 command line boot parameter passed to the panic-ed
1702 kernel. Please take a look at Documentation/kdump/kdump.txt
1703 for more details about crash dumps.
1704
1705 Usage of bzImage for capturing the crash dump is recommended as
1706 one does not have to build two kernels. Same kernel can be used
1707 as production kernel and capture kernel. Above option should have
1708 gone away after relocatable bzImage support is introduced. But it
1709 is present because there are users out there who continue to use
1710 vmlinux for dump capture. This option should go away down the
1711 line.
1712
1713 Don't change this unless you know what you are doing.
1714
1715 config RELOCATABLE
1716 bool "Build a relocatable kernel"
1717 default y
1718 ---help---
1719 This builds a kernel image that retains relocation information
1720 so it can be loaded someplace besides the default 1MB.
1721 The relocations tend to make the kernel binary about 10% larger,
1722 but are discarded at runtime.
1723
1724 One use is for the kexec on panic case where the recovery kernel
1725 must live at a different physical address than the primary
1726 kernel.
1727
1728 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1729 it has been loaded at and the compile time physical address
1730 (CONFIG_PHYSICAL_START) is ignored.
1731
1732 # Relocation on x86-32 needs some additional build support
1733 config X86_NEED_RELOCS
1734 def_bool y
1735 depends on X86_32 && RELOCATABLE
1736
1737 config PHYSICAL_ALIGN
1738 hex "Alignment value to which kernel should be aligned"
1739 default "0x1000000"
1740 range 0x2000 0x1000000 if X86_32
1741 range 0x200000 0x1000000 if X86_64
1742 ---help---
1743 This value puts the alignment restrictions on physical address
1744 where kernel is loaded and run from. Kernel is compiled for an
1745 address which meets above alignment restriction.
1746
1747 If bootloader loads the kernel at a non-aligned address and
1748 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1749 address aligned to above value and run from there.
1750
1751 If bootloader loads the kernel at a non-aligned address and
1752 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1753 load address and decompress itself to the address it has been
1754 compiled for and run from there. The address for which kernel is
1755 compiled already meets above alignment restrictions. Hence the
1756 end result is that kernel runs from a physical address meeting
1757 above alignment restrictions.
1758
1759 On 32-bit this value must be a multiple of 0x2000. On 64-bit
1760 this value must be a multiple of 0x200000.
1761
1762 Don't change this unless you know what you are doing.
1763
1764 config HOTPLUG_CPU
1765 bool "Support for hot-pluggable CPUs"
1766 depends on SMP
1767 ---help---
1768 Say Y here to allow turning CPUs off and on. CPUs can be
1769 controlled through /sys/devices/system/cpu.
1770 ( Note: power management support will enable this option
1771 automatically on SMP systems. )
1772 Say N if you want to disable CPU hotplug.
1773
1774 config BOOTPARAM_HOTPLUG_CPU0
1775 bool "Set default setting of cpu0_hotpluggable"
1776 default n
1777 depends on HOTPLUG_CPU
1778 ---help---
1779 Set whether default state of cpu0_hotpluggable is on or off.
1780
1781 Say Y here to enable CPU0 hotplug by default. If this switch
1782 is turned on, there is no need to give cpu0_hotplug kernel
1783 parameter and the CPU0 hotplug feature is enabled by default.
1784
1785 Please note: there are two known CPU0 dependencies if you want
1786 to enable the CPU0 hotplug feature either by this switch or by
1787 cpu0_hotplug kernel parameter.
1788
1789 First, resume from hibernate or suspend always starts from CPU0.
1790 So hibernate and suspend are prevented if CPU0 is offline.
1791
1792 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1793 offline if any interrupt can not migrate out of CPU0. There may
1794 be other CPU0 dependencies.
1795
1796 Please make sure the dependencies are under your control before
1797 you enable this feature.
1798
1799 Say N if you don't want to enable CPU0 hotplug feature by default.
1800 You still can enable the CPU0 hotplug feature at boot by kernel
1801 parameter cpu0_hotplug.
1802
1803 config DEBUG_HOTPLUG_CPU0
1804 def_bool n
1805 prompt "Debug CPU0 hotplug"
1806 depends on HOTPLUG_CPU
1807 ---help---
1808 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1809 soon as possible and boots up userspace with CPU0 offlined. User
1810 can online CPU0 back after boot time.
1811
1812 To debug CPU0 hotplug, you need to enable CPU0 offline/online
1813 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
1814 compilation or giving cpu0_hotplug kernel parameter at boot.
1815
1816 If unsure, say N.
1817
1818 config COMPAT_VDSO
1819 def_bool y
1820 prompt "Compat VDSO support"
1821 depends on X86_32 || IA32_EMULATION
1822 ---help---
1823 Map the 32-bit VDSO to the predictable old-style address too.
1824
1825 Say N here if you are running a sufficiently recent glibc
1826 version (2.3.3 or later), to remove the high-mapped
1827 VDSO mapping and to exclusively use the randomized VDSO.
1828
1829 If unsure, say Y.
1830
1831 config CMDLINE_BOOL
1832 bool "Built-in kernel command line"
1833 ---help---
1834 Allow for specifying boot arguments to the kernel at
1835 build time. On some systems (e.g. embedded ones), it is
1836 necessary or convenient to provide some or all of the
1837 kernel boot arguments with the kernel itself (that is,
1838 to not rely on the boot loader to provide them.)
1839
1840 To compile command line arguments into the kernel,
1841 set this option to 'Y', then fill in the
1842 the boot arguments in CONFIG_CMDLINE.
1843
1844 Systems with fully functional boot loaders (i.e. non-embedded)
1845 should leave this option set to 'N'.
1846
1847 config CMDLINE
1848 string "Built-in kernel command string"
1849 depends on CMDLINE_BOOL
1850 default ""
1851 ---help---
1852 Enter arguments here that should be compiled into the kernel
1853 image and used at boot time. If the boot loader provides a
1854 command line at boot time, it is appended to this string to
1855 form the full kernel command line, when the system boots.
1856
1857 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1858 change this behavior.
1859
1860 In most cases, the command line (whether built-in or provided
1861 by the boot loader) should specify the device for the root
1862 file system.
1863
1864 config CMDLINE_OVERRIDE
1865 bool "Built-in command line overrides boot loader arguments"
1866 depends on CMDLINE_BOOL
1867 ---help---
1868 Set this option to 'Y' to have the kernel ignore the boot loader
1869 command line, and use ONLY the built-in command line.
1870
1871 This is used to work around broken boot loaders. This should
1872 be set to 'N' under normal conditions.
1873
1874 endmenu
1875
1876 config ARCH_ENABLE_MEMORY_HOTPLUG
1877 def_bool y
1878 depends on X86_64 || (X86_32 && HIGHMEM)
1879
1880 config ARCH_ENABLE_MEMORY_HOTREMOVE
1881 def_bool y
1882 depends on MEMORY_HOTPLUG
1883
1884 config USE_PERCPU_NUMA_NODE_ID
1885 def_bool y
1886 depends on NUMA
1887
1888 config ARCH_ENABLE_SPLIT_PMD_PTLOCK
1889 def_bool y
1890 depends on X86_64 || X86_PAE
1891
1892 menu "Power management and ACPI options"
1893
1894 config ARCH_HIBERNATION_HEADER
1895 def_bool y
1896 depends on X86_64 && HIBERNATION
1897
1898 source "kernel/power/Kconfig"
1899
1900 source "drivers/acpi/Kconfig"
1901
1902 source "drivers/sfi/Kconfig"
1903
1904 config X86_APM_BOOT
1905 def_bool y
1906 depends on APM
1907
1908 menuconfig APM
1909 tristate "APM (Advanced Power Management) BIOS support"
1910 depends on X86_32 && PM_SLEEP
1911 ---help---
1912 APM is a BIOS specification for saving power using several different
1913 techniques. This is mostly useful for battery powered laptops with
1914 APM compliant BIOSes. If you say Y here, the system time will be
1915 reset after a RESUME operation, the /proc/apm device will provide
1916 battery status information, and user-space programs will receive
1917 notification of APM "events" (e.g. battery status change).
1918
1919 If you select "Y" here, you can disable actual use of the APM
1920 BIOS by passing the "apm=off" option to the kernel at boot time.
1921
1922 Note that the APM support is almost completely disabled for
1923 machines with more than one CPU.
1924
1925 In order to use APM, you will need supporting software. For location
1926 and more information, read <file:Documentation/power/apm-acpi.txt>
1927 and the Battery Powered Linux mini-HOWTO, available from
1928 <http://www.tldp.org/docs.html#howto>.
1929
1930 This driver does not spin down disk drives (see the hdparm(8)
1931 manpage ("man 8 hdparm") for that), and it doesn't turn off
1932 VESA-compliant "green" monitors.
1933
1934 This driver does not support the TI 4000M TravelMate and the ACER
1935 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1936 desktop machines also don't have compliant BIOSes, and this driver
1937 may cause those machines to panic during the boot phase.
1938
1939 Generally, if you don't have a battery in your machine, there isn't
1940 much point in using this driver and you should say N. If you get
1941 random kernel OOPSes or reboots that don't seem to be related to
1942 anything, try disabling/enabling this option (or disabling/enabling
1943 APM in your BIOS).
1944
1945 Some other things you should try when experiencing seemingly random,
1946 "weird" problems:
1947
1948 1) make sure that you have enough swap space and that it is
1949 enabled.
1950 2) pass the "no-hlt" option to the kernel
1951 3) switch on floating point emulation in the kernel and pass
1952 the "no387" option to the kernel
1953 4) pass the "floppy=nodma" option to the kernel
1954 5) pass the "mem=4M" option to the kernel (thereby disabling
1955 all but the first 4 MB of RAM)
1956 6) make sure that the CPU is not over clocked.
1957 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1958 8) disable the cache from your BIOS settings
1959 9) install a fan for the video card or exchange video RAM
1960 10) install a better fan for the CPU
1961 11) exchange RAM chips
1962 12) exchange the motherboard.
1963
1964 To compile this driver as a module, choose M here: the
1965 module will be called apm.
1966
1967 if APM
1968
1969 config APM_IGNORE_USER_SUSPEND
1970 bool "Ignore USER SUSPEND"
1971 ---help---
1972 This option will ignore USER SUSPEND requests. On machines with a
1973 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1974 series notebooks, it is necessary to say Y because of a BIOS bug.
1975
1976 config APM_DO_ENABLE
1977 bool "Enable PM at boot time"
1978 ---help---
1979 Enable APM features at boot time. From page 36 of the APM BIOS
1980 specification: "When disabled, the APM BIOS does not automatically
1981 power manage devices, enter the Standby State, enter the Suspend
1982 State, or take power saving steps in response to CPU Idle calls."
1983 This driver will make CPU Idle calls when Linux is idle (unless this
1984 feature is turned off -- see "Do CPU IDLE calls", below). This
1985 should always save battery power, but more complicated APM features
1986 will be dependent on your BIOS implementation. You may need to turn
1987 this option off if your computer hangs at boot time when using APM
1988 support, or if it beeps continuously instead of suspending. Turn
1989 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1990 T400CDT. This is off by default since most machines do fine without
1991 this feature.
1992
1993 config APM_CPU_IDLE
1994 depends on CPU_IDLE
1995 bool "Make CPU Idle calls when idle"
1996 ---help---
1997 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1998 On some machines, this can activate improved power savings, such as
1999 a slowed CPU clock rate, when the machine is idle. These idle calls
2000 are made after the idle loop has run for some length of time (e.g.,
2001 333 mS). On some machines, this will cause a hang at boot time or
2002 whenever the CPU becomes idle. (On machines with more than one CPU,
2003 this option does nothing.)
2004
2005 config APM_DISPLAY_BLANK
2006 bool "Enable console blanking using APM"
2007 ---help---
2008 Enable console blanking using the APM. Some laptops can use this to
2009 turn off the LCD backlight when the screen blanker of the Linux
2010 virtual console blanks the screen. Note that this is only used by
2011 the virtual console screen blanker, and won't turn off the backlight
2012 when using the X Window system. This also doesn't have anything to
2013 do with your VESA-compliant power-saving monitor. Further, this
2014 option doesn't work for all laptops -- it might not turn off your
2015 backlight at all, or it might print a lot of errors to the console,
2016 especially if you are using gpm.
2017
2018 config APM_ALLOW_INTS
2019 bool "Allow interrupts during APM BIOS calls"
2020 ---help---
2021 Normally we disable external interrupts while we are making calls to
2022 the APM BIOS as a measure to lessen the effects of a badly behaving
2023 BIOS implementation. The BIOS should reenable interrupts if it
2024 needs to. Unfortunately, some BIOSes do not -- especially those in
2025 many of the newer IBM Thinkpads. If you experience hangs when you
2026 suspend, try setting this to Y. Otherwise, say N.
2027
2028 endif # APM
2029
2030 source "drivers/cpufreq/Kconfig"
2031
2032 source "drivers/cpuidle/Kconfig"
2033
2034 source "drivers/idle/Kconfig"
2035
2036 endmenu
2037
2038
2039 menu "Bus options (PCI etc.)"
2040
2041 config PCI
2042 bool "PCI support"
2043 default y
2044 ---help---
2045 Find out whether you have a PCI motherboard. PCI is the name of a
2046 bus system, i.e. the way the CPU talks to the other stuff inside
2047 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2048 VESA. If you have PCI, say Y, otherwise N.
2049
2050 choice
2051 prompt "PCI access mode"
2052 depends on X86_32 && PCI
2053 default PCI_GOANY
2054 ---help---
2055 On PCI systems, the BIOS can be used to detect the PCI devices and
2056 determine their configuration. However, some old PCI motherboards
2057 have BIOS bugs and may crash if this is done. Also, some embedded
2058 PCI-based systems don't have any BIOS at all. Linux can also try to
2059 detect the PCI hardware directly without using the BIOS.
2060
2061 With this option, you can specify how Linux should detect the
2062 PCI devices. If you choose "BIOS", the BIOS will be used,
2063 if you choose "Direct", the BIOS won't be used, and if you
2064 choose "MMConfig", then PCI Express MMCONFIG will be used.
2065 If you choose "Any", the kernel will try MMCONFIG, then the
2066 direct access method and falls back to the BIOS if that doesn't
2067 work. If unsure, go with the default, which is "Any".
2068
2069 config PCI_GOBIOS
2070 bool "BIOS"
2071
2072 config PCI_GOMMCONFIG
2073 bool "MMConfig"
2074
2075 config PCI_GODIRECT
2076 bool "Direct"
2077
2078 config PCI_GOOLPC
2079 bool "OLPC XO-1"
2080 depends on OLPC
2081
2082 config PCI_GOANY
2083 bool "Any"
2084
2085 endchoice
2086
2087 config PCI_BIOS
2088 def_bool y
2089 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2090
2091 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2092 config PCI_DIRECT
2093 def_bool y
2094 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2095
2096 config PCI_MMCONFIG
2097 def_bool y
2098 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2099
2100 config PCI_OLPC
2101 def_bool y
2102 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2103
2104 config PCI_XEN
2105 def_bool y
2106 depends on PCI && XEN
2107 select SWIOTLB_XEN
2108
2109 config PCI_DOMAINS
2110 def_bool y
2111 depends on PCI
2112
2113 config PCI_MMCONFIG
2114 bool "Support mmconfig PCI config space access"
2115 depends on X86_64 && PCI && ACPI
2116
2117 config PCI_CNB20LE_QUIRK
2118 bool "Read CNB20LE Host Bridge Windows" if EXPERT
2119 depends on PCI
2120 help
2121 Read the PCI windows out of the CNB20LE host bridge. This allows
2122 PCI hotplug to work on systems with the CNB20LE chipset which do
2123 not have ACPI.
2124
2125 There's no public spec for this chipset, and this functionality
2126 is known to be incomplete.
2127
2128 You should say N unless you know you need this.
2129
2130 source "drivers/pci/pcie/Kconfig"
2131
2132 source "drivers/pci/Kconfig"
2133
2134 # x86_64 have no ISA slots, but can have ISA-style DMA.
2135 config ISA_DMA_API
2136 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2137 default y
2138 help
2139 Enables ISA-style DMA support for devices requiring such controllers.
2140 If unsure, say Y.
2141
2142 if X86_32
2143
2144 config ISA
2145 bool "ISA support"
2146 ---help---
2147 Find out whether you have ISA slots on your motherboard. ISA is the
2148 name of a bus system, i.e. the way the CPU talks to the other stuff
2149 inside your box. Other bus systems are PCI, EISA, MicroChannel
2150 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2151 newer boards don't support it. If you have ISA, say Y, otherwise N.
2152
2153 config EISA
2154 bool "EISA support"
2155 depends on ISA
2156 ---help---
2157 The Extended Industry Standard Architecture (EISA) bus was
2158 developed as an open alternative to the IBM MicroChannel bus.
2159
2160 The EISA bus provided some of the features of the IBM MicroChannel
2161 bus while maintaining backward compatibility with cards made for
2162 the older ISA bus. The EISA bus saw limited use between 1988 and
2163 1995 when it was made obsolete by the PCI bus.
2164
2165 Say Y here if you are building a kernel for an EISA-based machine.
2166
2167 Otherwise, say N.
2168
2169 source "drivers/eisa/Kconfig"
2170
2171 config SCx200
2172 tristate "NatSemi SCx200 support"
2173 ---help---
2174 This provides basic support for National Semiconductor's
2175 (now AMD's) Geode processors. The driver probes for the
2176 PCI-IDs of several on-chip devices, so its a good dependency
2177 for other scx200_* drivers.
2178
2179 If compiled as a module, the driver is named scx200.
2180
2181 config SCx200HR_TIMER
2182 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2183 depends on SCx200
2184 default y
2185 ---help---
2186 This driver provides a clocksource built upon the on-chip
2187 27MHz high-resolution timer. Its also a workaround for
2188 NSC Geode SC-1100's buggy TSC, which loses time when the
2189 processor goes idle (as is done by the scheduler). The
2190 other workaround is idle=poll boot option.
2191
2192 config OLPC
2193 bool "One Laptop Per Child support"
2194 depends on !X86_PAE
2195 select GPIOLIB
2196 select OF
2197 select OF_PROMTREE
2198 select IRQ_DOMAIN
2199 ---help---
2200 Add support for detecting the unique features of the OLPC
2201 XO hardware.
2202
2203 config OLPC_XO1_PM
2204 bool "OLPC XO-1 Power Management"
2205 depends on OLPC && MFD_CS5535 && PM_SLEEP
2206 select MFD_CORE
2207 ---help---
2208 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2209
2210 config OLPC_XO1_RTC
2211 bool "OLPC XO-1 Real Time Clock"
2212 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2213 ---help---
2214 Add support for the XO-1 real time clock, which can be used as a
2215 programmable wakeup source.
2216
2217 config OLPC_XO1_SCI
2218 bool "OLPC XO-1 SCI extras"
2219 depends on OLPC && OLPC_XO1_PM
2220 depends on INPUT=y
2221 select POWER_SUPPLY
2222 select GPIO_CS5535
2223 select MFD_CORE
2224 ---help---
2225 Add support for SCI-based features of the OLPC XO-1 laptop:
2226 - EC-driven system wakeups
2227 - Power button
2228 - Ebook switch
2229 - Lid switch
2230 - AC adapter status updates
2231 - Battery status updates
2232
2233 config OLPC_XO15_SCI
2234 bool "OLPC XO-1.5 SCI extras"
2235 depends on OLPC && ACPI
2236 select POWER_SUPPLY
2237 ---help---
2238 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2239 - EC-driven system wakeups
2240 - AC adapter status updates
2241 - Battery status updates
2242
2243 config ALIX
2244 bool "PCEngines ALIX System Support (LED setup)"
2245 select GPIOLIB
2246 ---help---
2247 This option enables system support for the PCEngines ALIX.
2248 At present this just sets up LEDs for GPIO control on
2249 ALIX2/3/6 boards. However, other system specific setup should
2250 get added here.
2251
2252 Note: You must still enable the drivers for GPIO and LED support
2253 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2254
2255 Note: You have to set alix.force=1 for boards with Award BIOS.
2256
2257 config NET5501
2258 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2259 select GPIOLIB
2260 ---help---
2261 This option enables system support for the Soekris Engineering net5501.
2262
2263 config GEOS
2264 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2265 select GPIOLIB
2266 depends on DMI
2267 ---help---
2268 This option enables system support for the Traverse Technologies GEOS.
2269
2270 config TS5500
2271 bool "Technologic Systems TS-5500 platform support"
2272 depends on MELAN
2273 select CHECK_SIGNATURE
2274 select NEW_LEDS
2275 select LEDS_CLASS
2276 ---help---
2277 This option enables system support for the Technologic Systems TS-5500.
2278
2279 endif # X86_32
2280
2281 config AMD_NB
2282 def_bool y
2283 depends on CPU_SUP_AMD && PCI
2284
2285 source "drivers/pcmcia/Kconfig"
2286
2287 source "drivers/pci/hotplug/Kconfig"
2288
2289 config RAPIDIO
2290 tristate "RapidIO support"
2291 depends on PCI
2292 default n
2293 help
2294 If enabled this option will include drivers and the core
2295 infrastructure code to support RapidIO interconnect devices.
2296
2297 source "drivers/rapidio/Kconfig"
2298
2299 config X86_SYSFB
2300 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2301 help
2302 Firmwares often provide initial graphics framebuffers so the BIOS,
2303 bootloader or kernel can show basic video-output during boot for
2304 user-guidance and debugging. Historically, x86 used the VESA BIOS
2305 Extensions and EFI-framebuffers for this, which are mostly limited
2306 to x86.
2307 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2308 framebuffers so the new generic system-framebuffer drivers can be
2309 used on x86. If the framebuffer is not compatible with the generic
2310 modes, it is adverticed as fallback platform framebuffer so legacy
2311 drivers like efifb, vesafb and uvesafb can pick it up.
2312 If this option is not selected, all system framebuffers are always
2313 marked as fallback platform framebuffers as usual.
2314
2315 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2316 not be able to pick up generic system framebuffers if this option
2317 is selected. You are highly encouraged to enable simplefb as
2318 replacement if you select this option. simplefb can correctly deal
2319 with generic system framebuffers. But you should still keep vesafb
2320 and others enabled as fallback if a system framebuffer is
2321 incompatible with simplefb.
2322
2323 If unsure, say Y.
2324
2325 endmenu
2326
2327
2328 menu "Executable file formats / Emulations"
2329
2330 source "fs/Kconfig.binfmt"
2331
2332 config IA32_EMULATION
2333 bool "IA32 Emulation"
2334 depends on X86_64
2335 select BINFMT_ELF
2336 select COMPAT_BINFMT_ELF
2337 select HAVE_UID16
2338 ---help---
2339 Include code to run legacy 32-bit programs under a
2340 64-bit kernel. You should likely turn this on, unless you're
2341 100% sure that you don't have any 32-bit programs left.
2342
2343 config IA32_AOUT
2344 tristate "IA32 a.out support"
2345 depends on IA32_EMULATION
2346 ---help---
2347 Support old a.out binaries in the 32bit emulation.
2348
2349 config X86_X32
2350 bool "x32 ABI for 64-bit mode"
2351 depends on X86_64 && IA32_EMULATION
2352 ---help---
2353 Include code to run binaries for the x32 native 32-bit ABI
2354 for 64-bit processors. An x32 process gets access to the
2355 full 64-bit register file and wide data path while leaving
2356 pointers at 32 bits for smaller memory footprint.
2357
2358 You will need a recent binutils (2.22 or later) with
2359 elf32_x86_64 support enabled to compile a kernel with this
2360 option set.
2361
2362 config COMPAT
2363 def_bool y
2364 depends on IA32_EMULATION || X86_X32
2365 select ARCH_WANT_OLD_COMPAT_IPC
2366
2367 if COMPAT
2368 config COMPAT_FOR_U64_ALIGNMENT
2369 def_bool y
2370
2371 config SYSVIPC_COMPAT
2372 def_bool y
2373 depends on SYSVIPC
2374
2375 config KEYS_COMPAT
2376 def_bool y
2377 depends on KEYS
2378 endif
2379
2380 endmenu
2381
2382
2383 config HAVE_ATOMIC_IOMAP
2384 def_bool y
2385 depends on X86_32
2386
2387 config X86_DEV_DMA_OPS
2388 bool
2389 depends on X86_64 || STA2X11
2390
2391 config X86_DMA_REMAP
2392 bool
2393 depends on STA2X11
2394
2395 source "net/Kconfig"
2396
2397 source "drivers/Kconfig"
2398
2399 source "drivers/firmware/Kconfig"
2400
2401 source "fs/Kconfig"
2402
2403 source "arch/x86/Kconfig.debug"
2404
2405 source "security/Kconfig"
2406
2407 source "crypto/Kconfig"
2408
2409 source "arch/x86/kvm/Kconfig"
2410
2411 source "lib/Kconfig"