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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 HAVE_AOUT if X86_32
26 select HAVE_UNSTABLE_SCHED_CLOCK
27 select ARCH_SUPPORTS_NUMA_BALANCING
28 select ARCH_WANTS_PROT_NUMA_PROT_NONE
29 select HAVE_IDE
30 select HAVE_OPROFILE
31 select HAVE_PCSPKR_PLATFORM
32 select HAVE_PERF_EVENTS
33 select HAVE_IOREMAP_PROT
34 select HAVE_KPROBES
35 select HAVE_MEMBLOCK
36 select HAVE_MEMBLOCK_NODE_MAP
37 select ARCH_DISCARD_MEMBLOCK
38 select ARCH_WANT_OPTIONAL_GPIOLIB
39 select ARCH_WANT_FRAME_POINTERS
40 select HAVE_DMA_ATTRS
41 select HAVE_DMA_CONTIGUOUS if !SWIOTLB
42 select HAVE_KRETPROBES
43 select HAVE_OPTPROBES
44 select HAVE_KPROBES_ON_FTRACE
45 select HAVE_FTRACE_MCOUNT_RECORD
46 select HAVE_FENTRY if X86_64
47 select HAVE_C_RECORDMCOUNT
48 select HAVE_DYNAMIC_FTRACE
49 select HAVE_DYNAMIC_FTRACE_WITH_REGS
50 select HAVE_FUNCTION_TRACER
51 select HAVE_FUNCTION_GRAPH_TRACER
52 select HAVE_FUNCTION_GRAPH_FP_TEST
53 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
54 select HAVE_SYSCALL_TRACEPOINTS
55 select SYSCTL_EXCEPTION_TRACE
56 select HAVE_KVM
57 select HAVE_ARCH_KGDB
58 select HAVE_ARCH_TRACEHOOK
59 select HAVE_GENERIC_DMA_COHERENT if X86_32
60 select HAVE_EFFICIENT_UNALIGNED_ACCESS
61 select USER_STACKTRACE_SUPPORT
62 select HAVE_REGS_AND_STACK_ACCESS_API
63 select HAVE_DMA_API_DEBUG
64 select HAVE_KERNEL_GZIP
65 select HAVE_KERNEL_BZIP2
66 select HAVE_KERNEL_LZMA
67 select HAVE_KERNEL_XZ
68 select HAVE_KERNEL_LZO
69 select HAVE_KERNEL_LZ4
70 select HAVE_HW_BREAKPOINT
71 select HAVE_MIXED_BREAKPOINTS_REGS
72 select PERF_EVENTS
73 select HAVE_PERF_EVENTS_NMI
74 select HAVE_PERF_REGS
75 select HAVE_PERF_USER_STACK_DUMP
76 select HAVE_DEBUG_KMEMLEAK
77 select ANON_INODES
78 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
79 select HAVE_CMPXCHG_LOCAL
80 select HAVE_CMPXCHG_DOUBLE
81 select HAVE_ARCH_KMEMCHECK
82 select HAVE_USER_RETURN_NOTIFIER
83 select ARCH_BINFMT_ELF_RANDOMIZE_PIE
84 select HAVE_ARCH_JUMP_LABEL
85 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
86 select SPARSE_IRQ
87 select GENERIC_FIND_FIRST_BIT
88 select GENERIC_IRQ_PROBE
89 select GENERIC_PENDING_IRQ if SMP
90 select GENERIC_IRQ_SHOW
91 select GENERIC_CLOCKEVENTS_MIN_ADJUST
92 select IRQ_FORCED_THREADING
93 select HAVE_BPF_JIT if X86_64
94 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
95 select CLKEVT_I8253
96 select ARCH_HAVE_NMI_SAFE_CMPXCHG
97 select GENERIC_IOMAP
98 select DCACHE_WORD_ACCESS
99 select GENERIC_SMP_IDLE_THREAD
100 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
101 select HAVE_ARCH_SECCOMP_FILTER
102 select BUILDTIME_EXTABLE_SORT
103 select GENERIC_CMOS_UPDATE
104 select HAVE_ARCH_SOFT_DIRTY
105 select CLOCKSOURCE_WATCHDOG
106 select GENERIC_CLOCKEVENTS
107 select ARCH_CLOCKSOURCE_DATA if X86_64
108 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
109 select GENERIC_TIME_VSYSCALL if X86_64
110 select KTIME_SCALAR if X86_32
111 select GENERIC_STRNCPY_FROM_USER
112 select GENERIC_STRNLEN_USER
113 select HAVE_CONTEXT_TRACKING if X86_64
114 select HAVE_IRQ_TIME_ACCOUNTING
115 select VIRT_TO_BUS
116 select MODULES_USE_ELF_REL if X86_32
117 select MODULES_USE_ELF_RELA if X86_64
118 select CLONE_BACKWARDS if X86_32
119 select ARCH_USE_BUILTIN_BSWAP
120 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
121 select OLD_SIGACTION if X86_32
122 select COMPAT_OLD_SIGACTION if IA32_EMULATION
123 select RTC_LIB
124 select HAVE_DEBUG_STACKOVERFLOW
125 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
126
127 config INSTRUCTION_DECODER
128 def_bool y
129 depends on KPROBES || PERF_EVENTS || UPROBES
130
131 config OUTPUT_FORMAT
132 string
133 default "elf32-i386" if X86_32
134 default "elf64-x86-64" if X86_64
135
136 config ARCH_DEFCONFIG
137 string
138 default "arch/x86/configs/i386_defconfig" if X86_32
139 default "arch/x86/configs/x86_64_defconfig" if X86_64
140
141 config LOCKDEP_SUPPORT
142 def_bool y
143
144 config STACKTRACE_SUPPORT
145 def_bool y
146
147 config HAVE_LATENCYTOP_SUPPORT
148 def_bool y
149
150 config MMU
151 def_bool y
152
153 config SBUS
154 bool
155
156 config NEED_DMA_MAP_STATE
157 def_bool y
158 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG
159
160 config NEED_SG_DMA_LENGTH
161 def_bool y
162
163 config GENERIC_ISA_DMA
164 def_bool y
165 depends on ISA_DMA_API
166
167 config GENERIC_BUG
168 def_bool y
169 depends on BUG
170 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
171
172 config GENERIC_BUG_RELATIVE_POINTERS
173 bool
174
175 config GENERIC_HWEIGHT
176 def_bool y
177
178 config ARCH_MAY_HAVE_PC_FDC
179 def_bool y
180 depends on ISA_DMA_API
181
182 config RWSEM_XCHGADD_ALGORITHM
183 def_bool y
184
185 config GENERIC_CALIBRATE_DELAY
186 def_bool y
187
188 config ARCH_HAS_CPU_RELAX
189 def_bool y
190
191 config ARCH_HAS_CACHE_LINE_SIZE
192 def_bool y
193
194 config ARCH_HAS_CPU_AUTOPROBE
195 def_bool y
196
197 config HAVE_SETUP_PER_CPU_AREA
198 def_bool y
199
200 config NEED_PER_CPU_EMBED_FIRST_CHUNK
201 def_bool y
202
203 config NEED_PER_CPU_PAGE_FIRST_CHUNK
204 def_bool y
205
206 config ARCH_HIBERNATION_POSSIBLE
207 def_bool y
208
209 config ARCH_SUSPEND_POSSIBLE
210 def_bool y
211
212 config ARCH_WANT_HUGE_PMD_SHARE
213 def_bool y
214
215 config ARCH_WANT_GENERAL_HUGETLB
216 def_bool y
217
218 config ZONE_DMA32
219 bool
220 default X86_64
221
222 config AUDIT_ARCH
223 bool
224 default X86_64
225
226 config ARCH_SUPPORTS_OPTIMIZED_INLINING
227 def_bool y
228
229 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
230 def_bool y
231
232 config HAVE_INTEL_TXT
233 def_bool y
234 depends on INTEL_IOMMU && ACPI
235
236 config X86_32_SMP
237 def_bool y
238 depends on X86_32 && SMP
239
240 config X86_64_SMP
241 def_bool y
242 depends on X86_64 && SMP
243
244 config X86_HT
245 def_bool y
246 depends on SMP
247
248 config X86_32_LAZY_GS
249 def_bool y
250 depends on X86_32 && !CC_STACKPROTECTOR
251
252 config ARCH_HWEIGHT_CFLAGS
253 string
254 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
255 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
256
257 config ARCH_SUPPORTS_UPROBES
258 def_bool y
259
260 source "init/Kconfig"
261 source "kernel/Kconfig.freezer"
262
263 menu "Processor type and features"
264
265 config ZONE_DMA
266 bool "DMA memory allocation support" if EXPERT
267 default y
268 help
269 DMA memory allocation support allows devices with less than 32-bit
270 addressing to allocate within the first 16MB of address space.
271 Disable if no such devices will be used.
272
273 If unsure, say Y.
274
275 config SMP
276 bool "Symmetric multi-processing support"
277 ---help---
278 This enables support for systems with more than one CPU. If you have
279 a system with only one CPU, like most personal computers, say N. If
280 you have a system with more than one CPU, say Y.
281
282 If you say N here, the kernel will run on single and multiprocessor
283 machines, but will use only one CPU of a multiprocessor machine. If
284 you say Y here, the kernel will run on many, but not all,
285 singleprocessor machines. On a singleprocessor machine, the kernel
286 will run faster if you say N here.
287
288 Note that if you say Y here and choose architecture "586" or
289 "Pentium" under "Processor family", the kernel will not work on 486
290 architectures. Similarly, multiprocessor kernels for the "PPro"
291 architecture may not work on all Pentium based boards.
292
293 People using multiprocessor machines who say Y here should also say
294 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
295 Management" code will be disabled if you say Y here.
296
297 See also <file:Documentation/x86/i386/IO-APIC.txt>,
298 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
299 <http://www.tldp.org/docs.html#howto>.
300
301 If you don't know what to do here, say N.
302
303 config X86_X2APIC
304 bool "Support x2apic"
305 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
306 ---help---
307 This enables x2apic support on CPUs that have this feature.
308
309 This allows 32-bit apic IDs (so it can support very large systems),
310 and accesses the local apic via MSRs not via mmio.
311
312 If you don't know what to do here, say N.
313
314 config X86_MPPARSE
315 bool "Enable MPS table" if ACPI || SFI
316 default y
317 depends on X86_LOCAL_APIC
318 ---help---
319 For old smp systems that do not have proper acpi support. Newer systems
320 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
321
322 config X86_BIGSMP
323 bool "Support for big SMP systems with more than 8 CPUs"
324 depends on X86_32 && SMP
325 ---help---
326 This option is needed for the systems that have more than 8 CPUs
327
328 config GOLDFISH
329 def_bool y
330 depends on X86_GOLDFISH
331
332 if X86_32
333 config X86_EXTENDED_PLATFORM
334 bool "Support for extended (non-PC) x86 platforms"
335 default y
336 ---help---
337 If you disable this option then the kernel will only support
338 standard PC platforms. (which covers the vast majority of
339 systems out there.)
340
341 If you enable this option then you'll be able to select support
342 for the following (non-PC) 32 bit x86 platforms:
343 Goldfish (Android emulator)
344 AMD Elan
345 NUMAQ (IBM/Sequent)
346 RDC R-321x SoC
347 SGI 320/540 (Visual Workstation)
348 STA2X11-based (e.g. Northville)
349 Summit/EXA (IBM x440)
350 Unisys ES7000 IA32 series
351 Moorestown MID devices
352
353 If you have one of these systems, or if you want to build a
354 generic distribution kernel, say Y here - otherwise say N.
355 endif
356
357 if X86_64
358 config X86_EXTENDED_PLATFORM
359 bool "Support for extended (non-PC) x86 platforms"
360 default y
361 ---help---
362 If you disable this option then the kernel will only support
363 standard PC platforms. (which covers the vast majority of
364 systems out there.)
365
366 If you enable this option then you'll be able to select support
367 for the following (non-PC) 64 bit x86 platforms:
368 Numascale NumaChip
369 ScaleMP vSMP
370 SGI Ultraviolet
371
372 If you have one of these systems, or if you want to build a
373 generic distribution kernel, say Y here - otherwise say N.
374 endif
375 # This is an alphabetically sorted list of 64 bit extended platforms
376 # Please maintain the alphabetic order if and when there are additions
377 config X86_NUMACHIP
378 bool "Numascale NumaChip"
379 depends on X86_64
380 depends on X86_EXTENDED_PLATFORM
381 depends on NUMA
382 depends on SMP
383 depends on X86_X2APIC
384 depends on PCI_MMCONFIG
385 ---help---
386 Adds support for Numascale NumaChip large-SMP systems. Needed to
387 enable more than ~168 cores.
388 If you don't have one of these, you should say N here.
389
390 config X86_VSMP
391 bool "ScaleMP vSMP"
392 select HYPERVISOR_GUEST
393 select PARAVIRT
394 depends on X86_64 && PCI
395 depends on X86_EXTENDED_PLATFORM
396 depends on SMP
397 ---help---
398 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
399 supposed to run on these EM64T-based machines. Only choose this option
400 if you have one of these machines.
401
402 config X86_UV
403 bool "SGI Ultraviolet"
404 depends on X86_64
405 depends on X86_EXTENDED_PLATFORM
406 depends on NUMA
407 depends on X86_X2APIC
408 ---help---
409 This option is needed in order to support SGI Ultraviolet systems.
410 If you don't have one of these, you should say N here.
411
412 # Following is an alphabetically sorted list of 32 bit extended platforms
413 # Please maintain the alphabetic order if and when there are additions
414
415 config X86_GOLDFISH
416 bool "Goldfish (Virtual Platform)"
417 depends on X86_32
418 depends on X86_EXTENDED_PLATFORM
419 ---help---
420 Enable support for the Goldfish virtual platform used primarily
421 for Android development. Unless you are building for the Android
422 Goldfish emulator say N here.
423
424 config X86_INTEL_CE
425 bool "CE4100 TV platform"
426 depends on PCI
427 depends on PCI_GODIRECT
428 depends on X86_32
429 depends on X86_EXTENDED_PLATFORM
430 select X86_REBOOTFIXUPS
431 select OF
432 select OF_EARLY_FLATTREE
433 select IRQ_DOMAIN
434 ---help---
435 Select for the Intel CE media processor (CE4100) SOC.
436 This option compiles in support for the CE4100 SOC for settop
437 boxes and media devices.
438
439 config X86_WANT_INTEL_MID
440 bool "Intel MID platform support"
441 depends on X86_32
442 depends on X86_EXTENDED_PLATFORM
443 ---help---
444 Select to build a kernel capable of supporting Intel MID platform
445 systems which do not have the PCI legacy interfaces (Moorestown,
446 Medfield). If you are building for a PC class system say N here.
447
448 if X86_WANT_INTEL_MID
449
450 config X86_INTEL_MID
451 bool
452
453 config X86_MDFLD
454 bool "Medfield MID platform"
455 depends on PCI
456 depends on PCI_GOANY
457 depends on X86_IO_APIC
458 select X86_INTEL_MID
459 select SFI
460 select DW_APB_TIMER
461 select APB_TIMER
462 select I2C
463 select SPI
464 select INTEL_SCU_IPC
465 select X86_PLATFORM_DEVICES
466 select MFD_INTEL_MSIC
467 ---help---
468 Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin
469 Internet Device(MID) platform.
470 Unlike standard x86 PCs, Medfield does not have many legacy devices
471 nor standard legacy replacement devices/features. e.g. Medfield does
472 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
473
474 endif
475
476 config X86_INTEL_LPSS
477 bool "Intel Low Power Subsystem Support"
478 depends on ACPI
479 select COMMON_CLK
480 select PINCTRL
481 ---help---
482 Select to build support for Intel Low Power Subsystem such as
483 found on Intel Lynxpoint PCH. Selecting this option enables
484 things like clock tree (common clock framework) and pincontrol
485 which are needed by the LPSS peripheral drivers.
486
487 config X86_RDC321X
488 bool "RDC R-321x SoC"
489 depends on X86_32
490 depends on X86_EXTENDED_PLATFORM
491 select M486
492 select X86_REBOOTFIXUPS
493 ---help---
494 This option is needed for RDC R-321x system-on-chip, also known
495 as R-8610-(G).
496 If you don't have one of these chips, you should say N here.
497
498 config X86_32_NON_STANDARD
499 bool "Support non-standard 32-bit SMP architectures"
500 depends on X86_32 && SMP
501 depends on X86_EXTENDED_PLATFORM
502 ---help---
503 This option compiles in the NUMAQ, Summit, bigsmp, ES7000,
504 STA2X11, default subarchitectures. It is intended for a generic
505 binary kernel. If you select them all, kernel will probe it
506 one by one and will fallback to default.
507
508 # Alphabetically sorted list of Non standard 32 bit platforms
509
510 config X86_NUMAQ
511 bool "NUMAQ (IBM/Sequent)"
512 depends on X86_32_NON_STANDARD
513 depends on PCI
514 select NUMA
515 select X86_MPPARSE
516 ---help---
517 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
518 NUMA multiquad box. This changes the way that processors are
519 bootstrapped, and uses Clustered Logical APIC addressing mode instead
520 of Flat Logical. You will need a new lynxer.elf file to flash your
521 firmware with - send email to <Martin.Bligh@us.ibm.com>.
522
523 config X86_SUPPORTS_MEMORY_FAILURE
524 def_bool y
525 # MCE code calls memory_failure():
526 depends on X86_MCE
527 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
528 depends on !X86_NUMAQ
529 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
530 depends on X86_64 || !SPARSEMEM
531 select ARCH_SUPPORTS_MEMORY_FAILURE
532
533 config X86_VISWS
534 bool "SGI 320/540 (Visual Workstation)"
535 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
536 depends on X86_32_NON_STANDARD
537 ---help---
538 The SGI Visual Workstation series is an IA32-based workstation
539 based on SGI systems chips with some legacy PC hardware attached.
540
541 Say Y here to create a kernel to run on the SGI 320 or 540.
542
543 A kernel compiled for the Visual Workstation will run on general
544 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
545
546 config STA2X11
547 bool "STA2X11 Companion Chip Support"
548 depends on X86_32_NON_STANDARD && PCI
549 select X86_DEV_DMA_OPS
550 select X86_DMA_REMAP
551 select SWIOTLB
552 select MFD_STA2X11
553 select ARCH_REQUIRE_GPIOLIB
554 default n
555 ---help---
556 This adds support for boards based on the STA2X11 IO-Hub,
557 a.k.a. "ConneXt". The chip is used in place of the standard
558 PC chipset, so all "standard" peripherals are missing. If this
559 option is selected the kernel will still be able to boot on
560 standard PC machines.
561
562 config X86_SUMMIT
563 bool "Summit/EXA (IBM x440)"
564 depends on X86_32_NON_STANDARD
565 ---help---
566 This option is needed for IBM systems that use the Summit/EXA chipset.
567 In particular, it is needed for the x440.
568
569 config X86_ES7000
570 bool "Unisys ES7000 IA32 series"
571 depends on X86_32_NON_STANDARD && X86_BIGSMP
572 ---help---
573 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
574 supposed to run on an IA32-based Unisys ES7000 system.
575
576 config X86_32_IRIS
577 tristate "Eurobraille/Iris poweroff module"
578 depends on X86_32
579 ---help---
580 The Iris machines from EuroBraille do not have APM or ACPI support
581 to shut themselves down properly. A special I/O sequence is
582 needed to do so, which is what this module does at
583 kernel shutdown.
584
585 This is only for Iris machines from EuroBraille.
586
587 If unused, say N.
588
589 config SCHED_OMIT_FRAME_POINTER
590 def_bool y
591 prompt "Single-depth WCHAN output"
592 depends on X86
593 ---help---
594 Calculate simpler /proc/<PID>/wchan values. If this option
595 is disabled then wchan values will recurse back to the
596 caller function. This provides more accurate wchan values,
597 at the expense of slightly more scheduling overhead.
598
599 If in doubt, say "Y".
600
601 menuconfig HYPERVISOR_GUEST
602 bool "Linux guest support"
603 ---help---
604 Say Y here to enable options for running Linux under various hyper-
605 visors. This option enables basic hypervisor detection and platform
606 setup.
607
608 If you say N, all options in this submenu will be skipped and
609 disabled, and Linux guest support won't be built in.
610
611 if HYPERVISOR_GUEST
612
613 config PARAVIRT
614 bool "Enable paravirtualization code"
615 ---help---
616 This changes the kernel so it can modify itself when it is run
617 under a hypervisor, potentially improving performance significantly
618 over full virtualization. However, when run without a hypervisor
619 the kernel is theoretically slower and slightly larger.
620
621 config PARAVIRT_DEBUG
622 bool "paravirt-ops debugging"
623 depends on PARAVIRT && DEBUG_KERNEL
624 ---help---
625 Enable to debug paravirt_ops internals. Specifically, BUG if
626 a paravirt_op is missing when it is called.
627
628 config PARAVIRT_SPINLOCKS
629 bool "Paravirtualization layer for spinlocks"
630 depends on PARAVIRT && SMP
631 select UNINLINE_SPIN_UNLOCK
632 ---help---
633 Paravirtualized spinlocks allow a pvops backend to replace the
634 spinlock implementation with something virtualization-friendly
635 (for example, block the virtual CPU rather than spinning).
636
637 It has a minimal impact on native kernels and gives a nice performance
638 benefit on paravirtualized KVM / Xen kernels.
639
640 If you are unsure how to answer this question, answer Y.
641
642 source "arch/x86/xen/Kconfig"
643
644 config KVM_GUEST
645 bool "KVM Guest support (including kvmclock)"
646 depends on PARAVIRT
647 select PARAVIRT_CLOCK
648 default y
649 ---help---
650 This option enables various optimizations for running under the KVM
651 hypervisor. It includes a paravirtualized clock, so that instead
652 of relying on a PIT (or probably other) emulation by the
653 underlying device model, the host provides the guest with
654 timing infrastructure such as time of day, and system time
655
656 config KVM_DEBUG_FS
657 bool "Enable debug information for KVM Guests in debugfs"
658 depends on KVM_GUEST && DEBUG_FS
659 default n
660 ---help---
661 This option enables collection of various statistics for KVM guest.
662 Statistics are displayed in debugfs filesystem. Enabling this option
663 may incur significant overhead.
664
665 source "arch/x86/lguest/Kconfig"
666
667 config PARAVIRT_TIME_ACCOUNTING
668 bool "Paravirtual steal time accounting"
669 depends on PARAVIRT
670 default n
671 ---help---
672 Select this option to enable fine granularity task steal time
673 accounting. Time spent executing other tasks in parallel with
674 the current vCPU is discounted from the vCPU power. To account for
675 that, there can be a small performance impact.
676
677 If in doubt, say N here.
678
679 config PARAVIRT_CLOCK
680 bool
681
682 endif #HYPERVISOR_GUEST
683
684 config NO_BOOTMEM
685 def_bool y
686
687 config MEMTEST
688 bool "Memtest"
689 ---help---
690 This option adds a kernel parameter 'memtest', which allows memtest
691 to be set.
692 memtest=0, mean disabled; -- default
693 memtest=1, mean do 1 test pattern;
694 ...
695 memtest=4, mean do 4 test patterns.
696 If you are unsure how to answer this question, answer N.
697
698 config X86_SUMMIT_NUMA
699 def_bool y
700 depends on X86_32 && NUMA && X86_32_NON_STANDARD
701
702 config X86_CYCLONE_TIMER
703 def_bool y
704 depends on X86_SUMMIT
705
706 source "arch/x86/Kconfig.cpu"
707
708 config HPET_TIMER
709 def_bool X86_64
710 prompt "HPET Timer Support" if X86_32
711 ---help---
712 Use the IA-PC HPET (High Precision Event Timer) to manage
713 time in preference to the PIT and RTC, if a HPET is
714 present.
715 HPET is the next generation timer replacing legacy 8254s.
716 The HPET provides a stable time base on SMP
717 systems, unlike the TSC, but it is more expensive to access,
718 as it is off-chip. You can find the HPET spec at
719 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
720
721 You can safely choose Y here. However, HPET will only be
722 activated if the platform and the BIOS support this feature.
723 Otherwise the 8254 will be used for timing services.
724
725 Choose N to continue using the legacy 8254 timer.
726
727 config HPET_EMULATE_RTC
728 def_bool y
729 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
730
731 config APB_TIMER
732 def_bool y if X86_INTEL_MID
733 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
734 select DW_APB_TIMER
735 depends on X86_INTEL_MID && SFI
736 help
737 APB timer is the replacement for 8254, HPET on X86 MID platforms.
738 The APBT provides a stable time base on SMP
739 systems, unlike the TSC, but it is more expensive to access,
740 as it is off-chip. APB timers are always running regardless of CPU
741 C states, they are used as per CPU clockevent device when possible.
742
743 # Mark as expert because too many people got it wrong.
744 # The code disables itself when not needed.
745 config DMI
746 default y
747 bool "Enable DMI scanning" if EXPERT
748 ---help---
749 Enabled scanning of DMI to identify machine quirks. Say Y
750 here unless you have verified that your setup is not
751 affected by entries in the DMI blacklist. Required by PNP
752 BIOS code.
753
754 config GART_IOMMU
755 bool "Old AMD GART IOMMU support"
756 select SWIOTLB
757 depends on X86_64 && PCI && AMD_NB
758 ---help---
759 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
760 GART based hardware IOMMUs.
761
762 The GART supports full DMA access for devices with 32-bit access
763 limitations, on systems with more than 3 GB. This is usually needed
764 for USB, sound, many IDE/SATA chipsets and some other devices.
765
766 Newer systems typically have a modern AMD IOMMU, supported via
767 the CONFIG_AMD_IOMMU=y config option.
768
769 In normal configurations this driver is only active when needed:
770 there's more than 3 GB of memory and the system contains a
771 32-bit limited device.
772
773 If unsure, say Y.
774
775 config CALGARY_IOMMU
776 bool "IBM Calgary IOMMU support"
777 select SWIOTLB
778 depends on X86_64 && PCI
779 ---help---
780 Support for hardware IOMMUs in IBM's xSeries x366 and x460
781 systems. Needed to run systems with more than 3GB of memory
782 properly with 32-bit PCI devices that do not support DAC
783 (Double Address Cycle). Calgary also supports bus level
784 isolation, where all DMAs pass through the IOMMU. This
785 prevents them from going anywhere except their intended
786 destination. This catches hard-to-find kernel bugs and
787 mis-behaving drivers and devices that do not use the DMA-API
788 properly to set up their DMA buffers. The IOMMU can be
789 turned off at boot time with the iommu=off parameter.
790 Normally the kernel will make the right choice by itself.
791 If unsure, say Y.
792
793 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
794 def_bool y
795 prompt "Should Calgary be enabled by default?"
796 depends on CALGARY_IOMMU
797 ---help---
798 Should Calgary be enabled by default? if you choose 'y', Calgary
799 will be used (if it exists). If you choose 'n', Calgary will not be
800 used even if it exists. If you choose 'n' and would like to use
801 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
802 If unsure, say Y.
803
804 # need this always selected by IOMMU for the VIA workaround
805 config SWIOTLB
806 def_bool y if X86_64
807 ---help---
808 Support for software bounce buffers used on x86-64 systems
809 which don't have a hardware IOMMU. Using this PCI devices
810 which can only access 32-bits of memory can be used on systems
811 with more than 3 GB of memory.
812 If unsure, say Y.
813
814 config IOMMU_HELPER
815 def_bool y
816 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
817
818 config MAXSMP
819 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
820 depends on X86_64 && SMP && DEBUG_KERNEL
821 select CPUMASK_OFFSTACK
822 ---help---
823 Enable maximum number of CPUS and NUMA Nodes for this architecture.
824 If unsure, say N.
825
826 config NR_CPUS
827 int "Maximum number of CPUs" if SMP && !MAXSMP
828 range 2 8 if SMP && X86_32 && !X86_BIGSMP
829 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
830 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
831 default "1" if !SMP
832 default "8192" if MAXSMP
833 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
834 default "8" if SMP
835 ---help---
836 This allows you to specify the maximum number of CPUs which this
837 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
838 supported value is 4096, otherwise the maximum value is 512. The
839 minimum value which makes sense is 2.
840
841 This is purely to save memory - each supported CPU adds
842 approximately eight kilobytes to the kernel image.
843
844 config SCHED_SMT
845 bool "SMT (Hyperthreading) scheduler support"
846 depends on X86_HT
847 ---help---
848 SMT scheduler support improves the CPU scheduler's decision making
849 when dealing with Intel Pentium 4 chips with HyperThreading at a
850 cost of slightly increased overhead in some places. If unsure say
851 N here.
852
853 config SCHED_MC
854 def_bool y
855 prompt "Multi-core scheduler support"
856 depends on X86_HT
857 ---help---
858 Multi-core scheduler support improves the CPU scheduler's decision
859 making when dealing with multi-core CPU chips at a cost of slightly
860 increased overhead in some places. If unsure say N here.
861
862 source "kernel/Kconfig.preempt"
863
864 config X86_UP_APIC
865 bool "Local APIC support on uniprocessors"
866 depends on X86_32 && !SMP && !X86_32_NON_STANDARD && !PCI_MSI
867 ---help---
868 A local APIC (Advanced Programmable Interrupt Controller) is an
869 integrated interrupt controller in the CPU. If you have a single-CPU
870 system which has a processor with a local APIC, you can say Y here to
871 enable and use it. If you say Y here even though your machine doesn't
872 have a local APIC, then the kernel will still run with no slowdown at
873 all. The local APIC supports CPU-generated self-interrupts (timer,
874 performance counters), and the NMI watchdog which detects hard
875 lockups.
876
877 config X86_UP_IOAPIC
878 bool "IO-APIC support on uniprocessors"
879 depends on X86_UP_APIC
880 ---help---
881 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
882 SMP-capable replacement for PC-style interrupt controllers. Most
883 SMP systems and many recent uniprocessor systems have one.
884
885 If you have a single-CPU system with an IO-APIC, you can say Y here
886 to use it. If you say Y here even though your machine doesn't have
887 an IO-APIC, then the kernel will still run with no slowdown at all.
888
889 config X86_LOCAL_APIC
890 def_bool y
891 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
892
893 config X86_IO_APIC
894 def_bool y
895 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC || PCI_MSI
896
897 config X86_VISWS_APIC
898 def_bool y
899 depends on X86_32 && X86_VISWS
900
901 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
902 bool "Reroute for broken boot IRQs"
903 depends on X86_IO_APIC
904 ---help---
905 This option enables a workaround that fixes a source of
906 spurious interrupts. This is recommended when threaded
907 interrupt handling is used on systems where the generation of
908 superfluous "boot interrupts" cannot be disabled.
909
910 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
911 entry in the chipset's IO-APIC is masked (as, e.g. the RT
912 kernel does during interrupt handling). On chipsets where this
913 boot IRQ generation cannot be disabled, this workaround keeps
914 the original IRQ line masked so that only the equivalent "boot
915 IRQ" is delivered to the CPUs. The workaround also tells the
916 kernel to set up the IRQ handler on the boot IRQ line. In this
917 way only one interrupt is delivered to the kernel. Otherwise
918 the spurious second interrupt may cause the kernel to bring
919 down (vital) interrupt lines.
920
921 Only affects "broken" chipsets. Interrupt sharing may be
922 increased on these systems.
923
924 config X86_MCE
925 bool "Machine Check / overheating reporting"
926 default y
927 ---help---
928 Machine Check support allows the processor to notify the
929 kernel if it detects a problem (e.g. overheating, data corruption).
930 The action the kernel takes depends on the severity of the problem,
931 ranging from warning messages to halting the machine.
932
933 config X86_MCE_INTEL
934 def_bool y
935 prompt "Intel MCE features"
936 depends on X86_MCE && X86_LOCAL_APIC
937 ---help---
938 Additional support for intel specific MCE features such as
939 the thermal monitor.
940
941 config X86_MCE_AMD
942 def_bool y
943 prompt "AMD MCE features"
944 depends on X86_MCE && X86_LOCAL_APIC
945 ---help---
946 Additional support for AMD specific MCE features such as
947 the DRAM Error Threshold.
948
949 config X86_ANCIENT_MCE
950 bool "Support for old Pentium 5 / WinChip machine checks"
951 depends on X86_32 && X86_MCE
952 ---help---
953 Include support for machine check handling on old Pentium 5 or WinChip
954 systems. These typically need to be enabled explicitely on the command
955 line.
956
957 config X86_MCE_THRESHOLD
958 depends on X86_MCE_AMD || X86_MCE_INTEL
959 def_bool y
960
961 config X86_MCE_INJECT
962 depends on X86_MCE
963 tristate "Machine check injector support"
964 ---help---
965 Provide support for injecting machine checks for testing purposes.
966 If you don't know what a machine check is and you don't do kernel
967 QA it is safe to say n.
968
969 config X86_THERMAL_VECTOR
970 def_bool y
971 depends on X86_MCE_INTEL
972
973 config VM86
974 bool "Enable VM86 support" if EXPERT
975 default y
976 depends on X86_32
977 ---help---
978 This option is required by programs like DOSEMU to run 16-bit legacy
979 code on X86 processors. It also may be needed by software like
980 XFree86 to initialize some video cards via BIOS. Disabling this
981 option saves about 6k.
982
983 config TOSHIBA
984 tristate "Toshiba Laptop support"
985 depends on X86_32
986 ---help---
987 This adds a driver to safely access the System Management Mode of
988 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
989 not work on models with a Phoenix BIOS. The System Management Mode
990 is used to set the BIOS and power saving options on Toshiba portables.
991
992 For information on utilities to make use of this driver see the
993 Toshiba Linux utilities web site at:
994 <http://www.buzzard.org.uk/toshiba/>.
995
996 Say Y if you intend to run this kernel on a Toshiba portable.
997 Say N otherwise.
998
999 config I8K
1000 tristate "Dell laptop support"
1001 select HWMON
1002 ---help---
1003 This adds a driver to safely access the System Management Mode
1004 of the CPU on the Dell Inspiron 8000. The System Management Mode
1005 is used to read cpu temperature and cooling fan status and to
1006 control the fans on the I8K portables.
1007
1008 This driver has been tested only on the Inspiron 8000 but it may
1009 also work with other Dell laptops. You can force loading on other
1010 models by passing the parameter `force=1' to the module. Use at
1011 your own risk.
1012
1013 For information on utilities to make use of this driver see the
1014 I8K Linux utilities web site at:
1015 <http://people.debian.org/~dz/i8k/>
1016
1017 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
1018 Say N otherwise.
1019
1020 config X86_REBOOTFIXUPS
1021 bool "Enable X86 board specific fixups for reboot"
1022 depends on X86_32
1023 ---help---
1024 This enables chipset and/or board specific fixups to be done
1025 in order to get reboot to work correctly. This is only needed on
1026 some combinations of hardware and BIOS. The symptom, for which
1027 this config is intended, is when reboot ends with a stalled/hung
1028 system.
1029
1030 Currently, the only fixup is for the Geode machines using
1031 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1032
1033 Say Y if you want to enable the fixup. Currently, it's safe to
1034 enable this option even if you don't need it.
1035 Say N otherwise.
1036
1037 config MICROCODE
1038 tristate "CPU microcode loading support"
1039 depends on CPU_SUP_AMD || CPU_SUP_INTEL
1040 select FW_LOADER
1041 ---help---
1042
1043 If you say Y here, you will be able to update the microcode on
1044 certain Intel and AMD processors. The Intel support is for the
1045 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1046 Xeon etc. The AMD support is for families 0x10 and later. You will
1047 obviously need the actual microcode binary data itself which is not
1048 shipped with the Linux kernel.
1049
1050 This option selects the general module only, you need to select
1051 at least one vendor specific module as well.
1052
1053 To compile this driver as a module, choose M here: the module
1054 will be called microcode.
1055
1056 config MICROCODE_INTEL
1057 bool "Intel microcode loading support"
1058 depends on MICROCODE
1059 default MICROCODE
1060 select FW_LOADER
1061 ---help---
1062 This options enables microcode patch loading support for Intel
1063 processors.
1064
1065 For latest news and information on obtaining all the required
1066 Intel ingredients for this driver, check:
1067 <http://www.urbanmyth.org/microcode/>.
1068
1069 config MICROCODE_AMD
1070 bool "AMD microcode loading support"
1071 depends on MICROCODE
1072 select FW_LOADER
1073 ---help---
1074 If you select this option, microcode patch loading support for AMD
1075 processors will be enabled.
1076
1077 config MICROCODE_OLD_INTERFACE
1078 def_bool y
1079 depends on MICROCODE
1080
1081 config MICROCODE_INTEL_LIB
1082 def_bool y
1083 depends on MICROCODE_INTEL
1084
1085 config MICROCODE_INTEL_EARLY
1086 def_bool n
1087
1088 config MICROCODE_AMD_EARLY
1089 def_bool n
1090
1091 config MICROCODE_EARLY
1092 bool "Early load microcode"
1093 depends on MICROCODE=y && BLK_DEV_INITRD
1094 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL
1095 select MICROCODE_AMD_EARLY if MICROCODE_AMD
1096 default y
1097 help
1098 This option provides functionality to read additional microcode data
1099 at the beginning of initrd image. The data tells kernel to load
1100 microcode to CPU's as early as possible. No functional change if no
1101 microcode data is glued to the initrd, therefore it's safe to say Y.
1102
1103 config X86_MSR
1104 tristate "/dev/cpu/*/msr - Model-specific register support"
1105 ---help---
1106 This device gives privileged processes access to the x86
1107 Model-Specific Registers (MSRs). It is a character device with
1108 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1109 MSR accesses are directed to a specific CPU on multi-processor
1110 systems.
1111
1112 config X86_CPUID
1113 tristate "/dev/cpu/*/cpuid - CPU information support"
1114 ---help---
1115 This device gives processes access to the x86 CPUID instruction to
1116 be executed on a specific processor. It is a character device
1117 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1118 /dev/cpu/31/cpuid.
1119
1120 choice
1121 prompt "High Memory Support"
1122 default HIGHMEM64G if X86_NUMAQ
1123 default HIGHMEM4G
1124 depends on X86_32
1125
1126 config NOHIGHMEM
1127 bool "off"
1128 depends on !X86_NUMAQ
1129 ---help---
1130 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1131 However, the address space of 32-bit x86 processors is only 4
1132 Gigabytes large. That means that, if you have a large amount of
1133 physical memory, not all of it can be "permanently mapped" by the
1134 kernel. The physical memory that's not permanently mapped is called
1135 "high memory".
1136
1137 If you are compiling a kernel which will never run on a machine with
1138 more than 1 Gigabyte total physical RAM, answer "off" here (default
1139 choice and suitable for most users). This will result in a "3GB/1GB"
1140 split: 3GB are mapped so that each process sees a 3GB virtual memory
1141 space and the remaining part of the 4GB virtual memory space is used
1142 by the kernel to permanently map as much physical memory as
1143 possible.
1144
1145 If the machine has between 1 and 4 Gigabytes physical RAM, then
1146 answer "4GB" here.
1147
1148 If more than 4 Gigabytes is used then answer "64GB" here. This
1149 selection turns Intel PAE (Physical Address Extension) mode on.
1150 PAE implements 3-level paging on IA32 processors. PAE is fully
1151 supported by Linux, PAE mode is implemented on all recent Intel
1152 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1153 then the kernel will not boot on CPUs that don't support PAE!
1154
1155 The actual amount of total physical memory will either be
1156 auto detected or can be forced by using a kernel command line option
1157 such as "mem=256M". (Try "man bootparam" or see the documentation of
1158 your boot loader (lilo or loadlin) about how to pass options to the
1159 kernel at boot time.)
1160
1161 If unsure, say "off".
1162
1163 config HIGHMEM4G
1164 bool "4GB"
1165 depends on !X86_NUMAQ
1166 ---help---
1167 Select this if you have a 32-bit processor and between 1 and 4
1168 gigabytes of physical RAM.
1169
1170 config HIGHMEM64G
1171 bool "64GB"
1172 depends on !M486
1173 select X86_PAE
1174 ---help---
1175 Select this if you have a 32-bit processor and more than 4
1176 gigabytes of physical RAM.
1177
1178 endchoice
1179
1180 choice
1181 prompt "Memory split" if EXPERT
1182 default VMSPLIT_3G
1183 depends on X86_32
1184 ---help---
1185 Select the desired split between kernel and user memory.
1186
1187 If the address range available to the kernel is less than the
1188 physical memory installed, the remaining memory will be available
1189 as "high memory". Accessing high memory is a little more costly
1190 than low memory, as it needs to be mapped into the kernel first.
1191 Note that increasing the kernel address space limits the range
1192 available to user programs, making the address space there
1193 tighter. Selecting anything other than the default 3G/1G split
1194 will also likely make your kernel incompatible with binary-only
1195 kernel modules.
1196
1197 If you are not absolutely sure what you are doing, leave this
1198 option alone!
1199
1200 config VMSPLIT_3G
1201 bool "3G/1G user/kernel split"
1202 config VMSPLIT_3G_OPT
1203 depends on !X86_PAE
1204 bool "3G/1G user/kernel split (for full 1G low memory)"
1205 config VMSPLIT_2G
1206 bool "2G/2G user/kernel split"
1207 config VMSPLIT_2G_OPT
1208 depends on !X86_PAE
1209 bool "2G/2G user/kernel split (for full 2G low memory)"
1210 config VMSPLIT_1G
1211 bool "1G/3G user/kernel split"
1212 endchoice
1213
1214 config PAGE_OFFSET
1215 hex
1216 default 0xB0000000 if VMSPLIT_3G_OPT
1217 default 0x80000000 if VMSPLIT_2G
1218 default 0x78000000 if VMSPLIT_2G_OPT
1219 default 0x40000000 if VMSPLIT_1G
1220 default 0xC0000000
1221 depends on X86_32
1222
1223 config HIGHMEM
1224 def_bool y
1225 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1226
1227 config X86_PAE
1228 bool "PAE (Physical Address Extension) Support"
1229 depends on X86_32 && !HIGHMEM4G
1230 ---help---
1231 PAE is required for NX support, and furthermore enables
1232 larger swapspace support for non-overcommit purposes. It
1233 has the cost of more pagetable lookup overhead, and also
1234 consumes more pagetable space per process.
1235
1236 config ARCH_PHYS_ADDR_T_64BIT
1237 def_bool y
1238 depends on X86_64 || X86_PAE
1239
1240 config ARCH_DMA_ADDR_T_64BIT
1241 def_bool y
1242 depends on X86_64 || HIGHMEM64G
1243
1244 config DIRECT_GBPAGES
1245 bool "Enable 1GB pages for kernel pagetables" if EXPERT
1246 default y
1247 depends on X86_64
1248 ---help---
1249 Allow the kernel linear mapping to use 1GB pages on CPUs that
1250 support it. This can improve the kernel's performance a tiny bit by
1251 reducing TLB pressure. If in doubt, say "Y".
1252
1253 # Common NUMA Features
1254 config NUMA
1255 bool "Numa Memory Allocation and Scheduler Support"
1256 depends on SMP
1257 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI))
1258 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1259 ---help---
1260 Enable NUMA (Non Uniform Memory Access) support.
1261
1262 The kernel will try to allocate memory used by a CPU on the
1263 local memory controller of the CPU and add some more
1264 NUMA awareness to the kernel.
1265
1266 For 64-bit this is recommended if the system is Intel Core i7
1267 (or later), AMD Opteron, or EM64T NUMA.
1268
1269 For 32-bit this is only needed on (rare) 32-bit-only platforms
1270 that support NUMA topologies, such as NUMAQ / Summit, or if you
1271 boot a 32-bit kernel on a 64-bit NUMA platform.
1272
1273 Otherwise, you should say N.
1274
1275 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1276 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1277
1278 config AMD_NUMA
1279 def_bool y
1280 prompt "Old style AMD Opteron NUMA detection"
1281 depends on X86_64 && NUMA && PCI
1282 ---help---
1283 Enable AMD NUMA node topology detection. You should say Y here if
1284 you have a multi processor AMD system. This uses an old method to
1285 read the NUMA configuration directly from the builtin Northbridge
1286 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1287 which also takes priority if both are compiled in.
1288
1289 config X86_64_ACPI_NUMA
1290 def_bool y
1291 prompt "ACPI NUMA detection"
1292 depends on X86_64 && NUMA && ACPI && PCI
1293 select ACPI_NUMA
1294 ---help---
1295 Enable ACPI SRAT based node topology detection.
1296
1297 # Some NUMA nodes have memory ranges that span
1298 # other nodes. Even though a pfn is valid and
1299 # between a node's start and end pfns, it may not
1300 # reside on that node. See memmap_init_zone()
1301 # for details.
1302 config NODES_SPAN_OTHER_NODES
1303 def_bool y
1304 depends on X86_64_ACPI_NUMA
1305
1306 config NUMA_EMU
1307 bool "NUMA emulation"
1308 depends on NUMA
1309 ---help---
1310 Enable NUMA emulation. A flat machine will be split
1311 into virtual nodes when booted with "numa=fake=N", where N is the
1312 number of nodes. This is only useful for debugging.
1313
1314 config NODES_SHIFT
1315 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1316 range 1 10
1317 default "10" if MAXSMP
1318 default "6" if X86_64
1319 default "4" if X86_NUMAQ
1320 default "3"
1321 depends on NEED_MULTIPLE_NODES
1322 ---help---
1323 Specify the maximum number of NUMA Nodes available on the target
1324 system. Increases memory reserved to accommodate various tables.
1325
1326 config ARCH_HAVE_MEMORY_PRESENT
1327 def_bool y
1328 depends on X86_32 && DISCONTIGMEM
1329
1330 config NEED_NODE_MEMMAP_SIZE
1331 def_bool y
1332 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1333
1334 config ARCH_FLATMEM_ENABLE
1335 def_bool y
1336 depends on X86_32 && !NUMA
1337
1338 config ARCH_DISCONTIGMEM_ENABLE
1339 def_bool y
1340 depends on NUMA && X86_32
1341
1342 config ARCH_DISCONTIGMEM_DEFAULT
1343 def_bool y
1344 depends on NUMA && X86_32
1345
1346 config ARCH_SPARSEMEM_ENABLE
1347 def_bool y
1348 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1349 select SPARSEMEM_STATIC if X86_32
1350 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1351
1352 config ARCH_SPARSEMEM_DEFAULT
1353 def_bool y
1354 depends on X86_64
1355
1356 config ARCH_SELECT_MEMORY_MODEL
1357 def_bool y
1358 depends on ARCH_SPARSEMEM_ENABLE
1359
1360 config ARCH_MEMORY_PROBE
1361 bool "Enable sysfs memory/probe interface"
1362 depends on X86_64 && MEMORY_HOTPLUG
1363 help
1364 This option enables a sysfs memory/probe interface for testing.
1365 See Documentation/memory-hotplug.txt for more information.
1366 If you are unsure how to answer this question, answer N.
1367
1368 config ARCH_PROC_KCORE_TEXT
1369 def_bool y
1370 depends on X86_64 && PROC_KCORE
1371
1372 config ILLEGAL_POINTER_VALUE
1373 hex
1374 default 0 if X86_32
1375 default 0xdead000000000000 if X86_64
1376
1377 source "mm/Kconfig"
1378
1379 config HIGHPTE
1380 bool "Allocate 3rd-level pagetables from highmem"
1381 depends on HIGHMEM
1382 ---help---
1383 The VM uses one page table entry for each page of physical memory.
1384 For systems with a lot of RAM, this can be wasteful of precious
1385 low memory. Setting this option will put user-space page table
1386 entries in high memory.
1387
1388 config X86_CHECK_BIOS_CORRUPTION
1389 bool "Check for low memory corruption"
1390 ---help---
1391 Periodically check for memory corruption in low memory, which
1392 is suspected to be caused by BIOS. Even when enabled in the
1393 configuration, it is disabled at runtime. Enable it by
1394 setting "memory_corruption_check=1" on the kernel command
1395 line. By default it scans the low 64k of memory every 60
1396 seconds; see the memory_corruption_check_size and
1397 memory_corruption_check_period parameters in
1398 Documentation/kernel-parameters.txt to adjust this.
1399
1400 When enabled with the default parameters, this option has
1401 almost no overhead, as it reserves a relatively small amount
1402 of memory and scans it infrequently. It both detects corruption
1403 and prevents it from affecting the running system.
1404
1405 It is, however, intended as a diagnostic tool; if repeatable
1406 BIOS-originated corruption always affects the same memory,
1407 you can use memmap= to prevent the kernel from using that
1408 memory.
1409
1410 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1411 bool "Set the default setting of memory_corruption_check"
1412 depends on X86_CHECK_BIOS_CORRUPTION
1413 default y
1414 ---help---
1415 Set whether the default state of memory_corruption_check is
1416 on or off.
1417
1418 config X86_RESERVE_LOW
1419 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1420 default 64
1421 range 4 640
1422 ---help---
1423 Specify the amount of low memory to reserve for the BIOS.
1424
1425 The first page contains BIOS data structures that the kernel
1426 must not use, so that page must always be reserved.
1427
1428 By default we reserve the first 64K of physical RAM, as a
1429 number of BIOSes are known to corrupt that memory range
1430 during events such as suspend/resume or monitor cable
1431 insertion, so it must not be used by the kernel.
1432
1433 You can set this to 4 if you are absolutely sure that you
1434 trust the BIOS to get all its memory reservations and usages
1435 right. If you know your BIOS have problems beyond the
1436 default 64K area, you can set this to 640 to avoid using the
1437 entire low memory range.
1438
1439 If you have doubts about the BIOS (e.g. suspend/resume does
1440 not work or there's kernel crashes after certain hardware
1441 hotplug events) then you might want to enable
1442 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1443 typical corruption patterns.
1444
1445 Leave this to the default value of 64 if you are unsure.
1446
1447 config MATH_EMULATION
1448 bool
1449 prompt "Math emulation" if X86_32
1450 ---help---
1451 Linux can emulate a math coprocessor (used for floating point
1452 operations) if you don't have one. 486DX and Pentium processors have
1453 a math coprocessor built in, 486SX and 386 do not, unless you added
1454 a 487DX or 387, respectively. (The messages during boot time can
1455 give you some hints here ["man dmesg"].) Everyone needs either a
1456 coprocessor or this emulation.
1457
1458 If you don't have a math coprocessor, you need to say Y here; if you
1459 say Y here even though you have a coprocessor, the coprocessor will
1460 be used nevertheless. (This behavior can be changed with the kernel
1461 command line option "no387", which comes handy if your coprocessor
1462 is broken. Try "man bootparam" or see the documentation of your boot
1463 loader (lilo or loadlin) about how to pass options to the kernel at
1464 boot time.) This means that it is a good idea to say Y here if you
1465 intend to use this kernel on different machines.
1466
1467 More information about the internals of the Linux math coprocessor
1468 emulation can be found in <file:arch/x86/math-emu/README>.
1469
1470 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1471 kernel, it won't hurt.
1472
1473 config MTRR
1474 def_bool y
1475 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1476 ---help---
1477 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1478 the Memory Type Range Registers (MTRRs) may be used to control
1479 processor access to memory ranges. This is most useful if you have
1480 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1481 allows bus write transfers to be combined into a larger transfer
1482 before bursting over the PCI/AGP bus. This can increase performance
1483 of image write operations 2.5 times or more. Saying Y here creates a
1484 /proc/mtrr file which may be used to manipulate your processor's
1485 MTRRs. Typically the X server should use this.
1486
1487 This code has a reasonably generic interface so that similar
1488 control registers on other processors can be easily supported
1489 as well:
1490
1491 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1492 Registers (ARRs) which provide a similar functionality to MTRRs. For
1493 these, the ARRs are used to emulate the MTRRs.
1494 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1495 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1496 write-combining. All of these processors are supported by this code
1497 and it makes sense to say Y here if you have one of them.
1498
1499 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1500 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1501 can lead to all sorts of problems, so it's good to say Y here.
1502
1503 You can safely say Y even if your machine doesn't have MTRRs, you'll
1504 just add about 9 KB to your kernel.
1505
1506 See <file:Documentation/x86/mtrr.txt> for more information.
1507
1508 config MTRR_SANITIZER
1509 def_bool y
1510 prompt "MTRR cleanup support"
1511 depends on MTRR
1512 ---help---
1513 Convert MTRR layout from continuous to discrete, so X drivers can
1514 add writeback entries.
1515
1516 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1517 The largest mtrr entry size for a continuous block can be set with
1518 mtrr_chunk_size.
1519
1520 If unsure, say Y.
1521
1522 config MTRR_SANITIZER_ENABLE_DEFAULT
1523 int "MTRR cleanup enable value (0-1)"
1524 range 0 1
1525 default "0"
1526 depends on MTRR_SANITIZER
1527 ---help---
1528 Enable mtrr cleanup default value
1529
1530 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1531 int "MTRR cleanup spare reg num (0-7)"
1532 range 0 7
1533 default "1"
1534 depends on MTRR_SANITIZER
1535 ---help---
1536 mtrr cleanup spare entries default, it can be changed via
1537 mtrr_spare_reg_nr=N on the kernel command line.
1538
1539 config X86_PAT
1540 def_bool y
1541 prompt "x86 PAT support" if EXPERT
1542 depends on MTRR
1543 ---help---
1544 Use PAT attributes to setup page level cache control.
1545
1546 PATs are the modern equivalents of MTRRs and are much more
1547 flexible than MTRRs.
1548
1549 Say N here if you see bootup problems (boot crash, boot hang,
1550 spontaneous reboots) or a non-working video driver.
1551
1552 If unsure, say Y.
1553
1554 config ARCH_USES_PG_UNCACHED
1555 def_bool y
1556 depends on X86_PAT
1557
1558 config ARCH_RANDOM
1559 def_bool y
1560 prompt "x86 architectural random number generator" if EXPERT
1561 ---help---
1562 Enable the x86 architectural RDRAND instruction
1563 (Intel Bull Mountain technology) to generate random numbers.
1564 If supported, this is a high bandwidth, cryptographically
1565 secure hardware random number generator.
1566
1567 config X86_SMAP
1568 def_bool y
1569 prompt "Supervisor Mode Access Prevention" if EXPERT
1570 ---help---
1571 Supervisor Mode Access Prevention (SMAP) is a security
1572 feature in newer Intel processors. There is a small
1573 performance cost if this enabled and turned on; there is
1574 also a small increase in the kernel size if this is enabled.
1575
1576 If unsure, say Y.
1577
1578 config EFI
1579 bool "EFI runtime service support"
1580 depends on ACPI
1581 select UCS2_STRING
1582 ---help---
1583 This enables the kernel to use EFI runtime services that are
1584 available (such as the EFI variable services).
1585
1586 This option is only useful on systems that have EFI firmware.
1587 In addition, you should use the latest ELILO loader available
1588 at <http://elilo.sourceforge.net> in order to take advantage
1589 of EFI runtime services. However, even with this option, the
1590 resultant kernel should continue to boot on existing non-EFI
1591 platforms.
1592
1593 config EFI_STUB
1594 bool "EFI stub support"
1595 depends on EFI
1596 ---help---
1597 This kernel feature allows a bzImage to be loaded directly
1598 by EFI firmware without the use of a bootloader.
1599
1600 See Documentation/efi-stub.txt for more information.
1601
1602 config SECCOMP
1603 def_bool y
1604 prompt "Enable seccomp to safely compute untrusted bytecode"
1605 ---help---
1606 This kernel feature is useful for number crunching applications
1607 that may need to compute untrusted bytecode during their
1608 execution. By using pipes or other transports made available to
1609 the process as file descriptors supporting the read/write
1610 syscalls, it's possible to isolate those applications in
1611 their own address space using seccomp. Once seccomp is
1612 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1613 and the task is only allowed to execute a few safe syscalls
1614 defined by each seccomp mode.
1615
1616 If unsure, say Y. Only embedded should say N here.
1617
1618 config CC_STACKPROTECTOR
1619 bool "Enable -fstack-protector buffer overflow detection"
1620 ---help---
1621 This option turns on the -fstack-protector GCC feature. This
1622 feature puts, at the beginning of functions, a canary value on
1623 the stack just before the return address, and validates
1624 the value just before actually returning. Stack based buffer
1625 overflows (that need to overwrite this return address) now also
1626 overwrite the canary, which gets detected and the attack is then
1627 neutralized via a kernel panic.
1628
1629 This feature requires gcc version 4.2 or above, or a distribution
1630 gcc with the feature backported. Older versions are automatically
1631 detected and for those versions, this configuration option is
1632 ignored. (and a warning is printed during bootup)
1633
1634 source kernel/Kconfig.hz
1635
1636 config KEXEC
1637 bool "kexec system call"
1638 ---help---
1639 kexec is a system call that implements the ability to shutdown your
1640 current kernel, and to start another kernel. It is like a reboot
1641 but it is independent of the system firmware. And like a reboot
1642 you can start any kernel with it, not just Linux.
1643
1644 The name comes from the similarity to the exec system call.
1645
1646 It is an ongoing process to be certain the hardware in a machine
1647 is properly shutdown, so do not be surprised if this code does not
1648 initially work for you. As of this writing the exact hardware
1649 interface is strongly in flux, so no good recommendation can be
1650 made.
1651
1652 config CRASH_DUMP
1653 bool "kernel crash dumps"
1654 depends on X86_64 || (X86_32 && HIGHMEM)
1655 ---help---
1656 Generate crash dump after being started by kexec.
1657 This should be normally only set in special crash dump kernels
1658 which are loaded in the main kernel with kexec-tools into
1659 a specially reserved region and then later executed after
1660 a crash by kdump/kexec. The crash dump kernel must be compiled
1661 to a memory address not used by the main kernel or BIOS using
1662 PHYSICAL_START, or it must be built as a relocatable image
1663 (CONFIG_RELOCATABLE=y).
1664 For more details see Documentation/kdump/kdump.txt
1665
1666 config KEXEC_JUMP
1667 bool "kexec jump"
1668 depends on KEXEC && HIBERNATION
1669 ---help---
1670 Jump between original kernel and kexeced kernel and invoke
1671 code in physical address mode via KEXEC
1672
1673 config PHYSICAL_START
1674 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1675 default "0x1000000"
1676 ---help---
1677 This gives the physical address where the kernel is loaded.
1678
1679 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1680 bzImage will decompress itself to above physical address and
1681 run from there. Otherwise, bzImage will run from the address where
1682 it has been loaded by the boot loader and will ignore above physical
1683 address.
1684
1685 In normal kdump cases one does not have to set/change this option
1686 as now bzImage can be compiled as a completely relocatable image
1687 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1688 address. This option is mainly useful for the folks who don't want
1689 to use a bzImage for capturing the crash dump and want to use a
1690 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1691 to be specifically compiled to run from a specific memory area
1692 (normally a reserved region) and this option comes handy.
1693
1694 So if you are using bzImage for capturing the crash dump,
1695 leave the value here unchanged to 0x1000000 and set
1696 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1697 for capturing the crash dump change this value to start of
1698 the reserved region. In other words, it can be set based on
1699 the "X" value as specified in the "crashkernel=YM@XM"
1700 command line boot parameter passed to the panic-ed
1701 kernel. Please take a look at Documentation/kdump/kdump.txt
1702 for more details about crash dumps.
1703
1704 Usage of bzImage for capturing the crash dump is recommended as
1705 one does not have to build two kernels. Same kernel can be used
1706 as production kernel and capture kernel. Above option should have
1707 gone away after relocatable bzImage support is introduced. But it
1708 is present because there are users out there who continue to use
1709 vmlinux for dump capture. This option should go away down the
1710 line.
1711
1712 Don't change this unless you know what you are doing.
1713
1714 config RELOCATABLE
1715 bool "Build a relocatable kernel"
1716 default y
1717 ---help---
1718 This builds a kernel image that retains relocation information
1719 so it can be loaded someplace besides the default 1MB.
1720 The relocations tend to make the kernel binary about 10% larger,
1721 but are discarded at runtime.
1722
1723 One use is for the kexec on panic case where the recovery kernel
1724 must live at a different physical address than the primary
1725 kernel.
1726
1727 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1728 it has been loaded at and the compile time physical address
1729 (CONFIG_PHYSICAL_START) is ignored.
1730
1731 # Relocation on x86-32 needs some additional build support
1732 config X86_NEED_RELOCS
1733 def_bool y
1734 depends on X86_32 && RELOCATABLE
1735
1736 config PHYSICAL_ALIGN
1737 hex "Alignment value to which kernel should be aligned"
1738 default "0x1000000"
1739 range 0x2000 0x1000000 if X86_32
1740 range 0x200000 0x1000000 if X86_64
1741 ---help---
1742 This value puts the alignment restrictions on physical address
1743 where kernel is loaded and run from. Kernel is compiled for an
1744 address which meets above alignment restriction.
1745
1746 If bootloader loads the kernel at a non-aligned address and
1747 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1748 address aligned to above value and run from there.
1749
1750 If bootloader loads the kernel at a non-aligned address and
1751 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1752 load address and decompress itself to the address it has been
1753 compiled for and run from there. The address for which kernel is
1754 compiled already meets above alignment restrictions. Hence the
1755 end result is that kernel runs from a physical address meeting
1756 above alignment restrictions.
1757
1758 On 32-bit this value must be a multiple of 0x2000. On 64-bit
1759 this value must be a multiple of 0x200000.
1760
1761 Don't change this unless you know what you are doing.
1762
1763 config HOTPLUG_CPU
1764 bool "Support for hot-pluggable CPUs"
1765 depends on SMP
1766 ---help---
1767 Say Y here to allow turning CPUs off and on. CPUs can be
1768 controlled through /sys/devices/system/cpu.
1769 ( Note: power management support will enable this option
1770 automatically on SMP systems. )
1771 Say N if you want to disable CPU hotplug.
1772
1773 config BOOTPARAM_HOTPLUG_CPU0
1774 bool "Set default setting of cpu0_hotpluggable"
1775 default n
1776 depends on HOTPLUG_CPU
1777 ---help---
1778 Set whether default state of cpu0_hotpluggable is on or off.
1779
1780 Say Y here to enable CPU0 hotplug by default. If this switch
1781 is turned on, there is no need to give cpu0_hotplug kernel
1782 parameter and the CPU0 hotplug feature is enabled by default.
1783
1784 Please note: there are two known CPU0 dependencies if you want
1785 to enable the CPU0 hotplug feature either by this switch or by
1786 cpu0_hotplug kernel parameter.
1787
1788 First, resume from hibernate or suspend always starts from CPU0.
1789 So hibernate and suspend are prevented if CPU0 is offline.
1790
1791 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1792 offline if any interrupt can not migrate out of CPU0. There may
1793 be other CPU0 dependencies.
1794
1795 Please make sure the dependencies are under your control before
1796 you enable this feature.
1797
1798 Say N if you don't want to enable CPU0 hotplug feature by default.
1799 You still can enable the CPU0 hotplug feature at boot by kernel
1800 parameter cpu0_hotplug.
1801
1802 config DEBUG_HOTPLUG_CPU0
1803 def_bool n
1804 prompt "Debug CPU0 hotplug"
1805 depends on HOTPLUG_CPU
1806 ---help---
1807 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1808 soon as possible and boots up userspace with CPU0 offlined. User
1809 can online CPU0 back after boot time.
1810
1811 To debug CPU0 hotplug, you need to enable CPU0 offline/online
1812 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
1813 compilation or giving cpu0_hotplug kernel parameter at boot.
1814
1815 If unsure, say N.
1816
1817 config COMPAT_VDSO
1818 def_bool y
1819 prompt "Compat VDSO support"
1820 depends on X86_32 || IA32_EMULATION
1821 ---help---
1822 Map the 32-bit VDSO to the predictable old-style address too.
1823
1824 Say N here if you are running a sufficiently recent glibc
1825 version (2.3.3 or later), to remove the high-mapped
1826 VDSO mapping and to exclusively use the randomized VDSO.
1827
1828 If unsure, say Y.
1829
1830 config CMDLINE_BOOL
1831 bool "Built-in kernel command line"
1832 ---help---
1833 Allow for specifying boot arguments to the kernel at
1834 build time. On some systems (e.g. embedded ones), it is
1835 necessary or convenient to provide some or all of the
1836 kernel boot arguments with the kernel itself (that is,
1837 to not rely on the boot loader to provide them.)
1838
1839 To compile command line arguments into the kernel,
1840 set this option to 'Y', then fill in the
1841 the boot arguments in CONFIG_CMDLINE.
1842
1843 Systems with fully functional boot loaders (i.e. non-embedded)
1844 should leave this option set to 'N'.
1845
1846 config CMDLINE
1847 string "Built-in kernel command string"
1848 depends on CMDLINE_BOOL
1849 default ""
1850 ---help---
1851 Enter arguments here that should be compiled into the kernel
1852 image and used at boot time. If the boot loader provides a
1853 command line at boot time, it is appended to this string to
1854 form the full kernel command line, when the system boots.
1855
1856 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1857 change this behavior.
1858
1859 In most cases, the command line (whether built-in or provided
1860 by the boot loader) should specify the device for the root
1861 file system.
1862
1863 config CMDLINE_OVERRIDE
1864 bool "Built-in command line overrides boot loader arguments"
1865 depends on CMDLINE_BOOL
1866 ---help---
1867 Set this option to 'Y' to have the kernel ignore the boot loader
1868 command line, and use ONLY the built-in command line.
1869
1870 This is used to work around broken boot loaders. This should
1871 be set to 'N' under normal conditions.
1872
1873 endmenu
1874
1875 config ARCH_ENABLE_MEMORY_HOTPLUG
1876 def_bool y
1877 depends on X86_64 || (X86_32 && HIGHMEM)
1878
1879 config ARCH_ENABLE_MEMORY_HOTREMOVE
1880 def_bool y
1881 depends on MEMORY_HOTPLUG
1882
1883 config USE_PERCPU_NUMA_NODE_ID
1884 def_bool y
1885 depends on NUMA
1886
1887 config ARCH_ENABLE_SPLIT_PMD_PTLOCK
1888 def_bool y
1889 depends on X86_64 || X86_PAE
1890
1891 menu "Power management and ACPI options"
1892
1893 config ARCH_HIBERNATION_HEADER
1894 def_bool y
1895 depends on X86_64 && HIBERNATION
1896
1897 source "kernel/power/Kconfig"
1898
1899 source "drivers/acpi/Kconfig"
1900
1901 source "drivers/sfi/Kconfig"
1902
1903 config X86_APM_BOOT
1904 def_bool y
1905 depends on APM
1906
1907 menuconfig APM
1908 tristate "APM (Advanced Power Management) BIOS support"
1909 depends on X86_32 && PM_SLEEP
1910 ---help---
1911 APM is a BIOS specification for saving power using several different
1912 techniques. This is mostly useful for battery powered laptops with
1913 APM compliant BIOSes. If you say Y here, the system time will be
1914 reset after a RESUME operation, the /proc/apm device will provide
1915 battery status information, and user-space programs will receive
1916 notification of APM "events" (e.g. battery status change).
1917
1918 If you select "Y" here, you can disable actual use of the APM
1919 BIOS by passing the "apm=off" option to the kernel at boot time.
1920
1921 Note that the APM support is almost completely disabled for
1922 machines with more than one CPU.
1923
1924 In order to use APM, you will need supporting software. For location
1925 and more information, read <file:Documentation/power/apm-acpi.txt>
1926 and the Battery Powered Linux mini-HOWTO, available from
1927 <http://www.tldp.org/docs.html#howto>.
1928
1929 This driver does not spin down disk drives (see the hdparm(8)
1930 manpage ("man 8 hdparm") for that), and it doesn't turn off
1931 VESA-compliant "green" monitors.
1932
1933 This driver does not support the TI 4000M TravelMate and the ACER
1934 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1935 desktop machines also don't have compliant BIOSes, and this driver
1936 may cause those machines to panic during the boot phase.
1937
1938 Generally, if you don't have a battery in your machine, there isn't
1939 much point in using this driver and you should say N. If you get
1940 random kernel OOPSes or reboots that don't seem to be related to
1941 anything, try disabling/enabling this option (or disabling/enabling
1942 APM in your BIOS).
1943
1944 Some other things you should try when experiencing seemingly random,
1945 "weird" problems:
1946
1947 1) make sure that you have enough swap space and that it is
1948 enabled.
1949 2) pass the "no-hlt" option to the kernel
1950 3) switch on floating point emulation in the kernel and pass
1951 the "no387" option to the kernel
1952 4) pass the "floppy=nodma" option to the kernel
1953 5) pass the "mem=4M" option to the kernel (thereby disabling
1954 all but the first 4 MB of RAM)
1955 6) make sure that the CPU is not over clocked.
1956 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1957 8) disable the cache from your BIOS settings
1958 9) install a fan for the video card or exchange video RAM
1959 10) install a better fan for the CPU
1960 11) exchange RAM chips
1961 12) exchange the motherboard.
1962
1963 To compile this driver as a module, choose M here: the
1964 module will be called apm.
1965
1966 if APM
1967
1968 config APM_IGNORE_USER_SUSPEND
1969 bool "Ignore USER SUSPEND"
1970 ---help---
1971 This option will ignore USER SUSPEND requests. On machines with a
1972 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1973 series notebooks, it is necessary to say Y because of a BIOS bug.
1974
1975 config APM_DO_ENABLE
1976 bool "Enable PM at boot time"
1977 ---help---
1978 Enable APM features at boot time. From page 36 of the APM BIOS
1979 specification: "When disabled, the APM BIOS does not automatically
1980 power manage devices, enter the Standby State, enter the Suspend
1981 State, or take power saving steps in response to CPU Idle calls."
1982 This driver will make CPU Idle calls when Linux is idle (unless this
1983 feature is turned off -- see "Do CPU IDLE calls", below). This
1984 should always save battery power, but more complicated APM features
1985 will be dependent on your BIOS implementation. You may need to turn
1986 this option off if your computer hangs at boot time when using APM
1987 support, or if it beeps continuously instead of suspending. Turn
1988 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1989 T400CDT. This is off by default since most machines do fine without
1990 this feature.
1991
1992 config APM_CPU_IDLE
1993 depends on CPU_IDLE
1994 bool "Make CPU Idle calls when idle"
1995 ---help---
1996 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1997 On some machines, this can activate improved power savings, such as
1998 a slowed CPU clock rate, when the machine is idle. These idle calls
1999 are made after the idle loop has run for some length of time (e.g.,
2000 333 mS). On some machines, this will cause a hang at boot time or
2001 whenever the CPU becomes idle. (On machines with more than one CPU,
2002 this option does nothing.)
2003
2004 config APM_DISPLAY_BLANK
2005 bool "Enable console blanking using APM"
2006 ---help---
2007 Enable console blanking using the APM. Some laptops can use this to
2008 turn off the LCD backlight when the screen blanker of the Linux
2009 virtual console blanks the screen. Note that this is only used by
2010 the virtual console screen blanker, and won't turn off the backlight
2011 when using the X Window system. This also doesn't have anything to
2012 do with your VESA-compliant power-saving monitor. Further, this
2013 option doesn't work for all laptops -- it might not turn off your
2014 backlight at all, or it might print a lot of errors to the console,
2015 especially if you are using gpm.
2016
2017 config APM_ALLOW_INTS
2018 bool "Allow interrupts during APM BIOS calls"
2019 ---help---
2020 Normally we disable external interrupts while we are making calls to
2021 the APM BIOS as a measure to lessen the effects of a badly behaving
2022 BIOS implementation. The BIOS should reenable interrupts if it
2023 needs to. Unfortunately, some BIOSes do not -- especially those in
2024 many of the newer IBM Thinkpads. If you experience hangs when you
2025 suspend, try setting this to Y. Otherwise, say N.
2026
2027 endif # APM
2028
2029 source "drivers/cpufreq/Kconfig"
2030
2031 source "drivers/cpuidle/Kconfig"
2032
2033 source "drivers/idle/Kconfig"
2034
2035 endmenu
2036
2037
2038 menu "Bus options (PCI etc.)"
2039
2040 config PCI
2041 bool "PCI support"
2042 default y
2043 ---help---
2044 Find out whether you have a PCI motherboard. PCI is the name of a
2045 bus system, i.e. the way the CPU talks to the other stuff inside
2046 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2047 VESA. If you have PCI, say Y, otherwise N.
2048
2049 choice
2050 prompt "PCI access mode"
2051 depends on X86_32 && PCI
2052 default PCI_GOANY
2053 ---help---
2054 On PCI systems, the BIOS can be used to detect the PCI devices and
2055 determine their configuration. However, some old PCI motherboards
2056 have BIOS bugs and may crash if this is done. Also, some embedded
2057 PCI-based systems don't have any BIOS at all. Linux can also try to
2058 detect the PCI hardware directly without using the BIOS.
2059
2060 With this option, you can specify how Linux should detect the
2061 PCI devices. If you choose "BIOS", the BIOS will be used,
2062 if you choose "Direct", the BIOS won't be used, and if you
2063 choose "MMConfig", then PCI Express MMCONFIG will be used.
2064 If you choose "Any", the kernel will try MMCONFIG, then the
2065 direct access method and falls back to the BIOS if that doesn't
2066 work. If unsure, go with the default, which is "Any".
2067
2068 config PCI_GOBIOS
2069 bool "BIOS"
2070
2071 config PCI_GOMMCONFIG
2072 bool "MMConfig"
2073
2074 config PCI_GODIRECT
2075 bool "Direct"
2076
2077 config PCI_GOOLPC
2078 bool "OLPC XO-1"
2079 depends on OLPC
2080
2081 config PCI_GOANY
2082 bool "Any"
2083
2084 endchoice
2085
2086 config PCI_BIOS
2087 def_bool y
2088 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2089
2090 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2091 config PCI_DIRECT
2092 def_bool y
2093 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2094
2095 config PCI_MMCONFIG
2096 def_bool y
2097 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2098
2099 config PCI_OLPC
2100 def_bool y
2101 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2102
2103 config PCI_XEN
2104 def_bool y
2105 depends on PCI && XEN
2106 select SWIOTLB_XEN
2107
2108 config PCI_DOMAINS
2109 def_bool y
2110 depends on PCI
2111
2112 config PCI_MMCONFIG
2113 bool "Support mmconfig PCI config space access"
2114 depends on X86_64 && PCI && ACPI
2115
2116 config PCI_CNB20LE_QUIRK
2117 bool "Read CNB20LE Host Bridge Windows" if EXPERT
2118 depends on PCI
2119 help
2120 Read the PCI windows out of the CNB20LE host bridge. This allows
2121 PCI hotplug to work on systems with the CNB20LE chipset which do
2122 not have ACPI.
2123
2124 There's no public spec for this chipset, and this functionality
2125 is known to be incomplete.
2126
2127 You should say N unless you know you need this.
2128
2129 source "drivers/pci/pcie/Kconfig"
2130
2131 source "drivers/pci/Kconfig"
2132
2133 # x86_64 have no ISA slots, but can have ISA-style DMA.
2134 config ISA_DMA_API
2135 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2136 default y
2137 help
2138 Enables ISA-style DMA support for devices requiring such controllers.
2139 If unsure, say Y.
2140
2141 if X86_32
2142
2143 config ISA
2144 bool "ISA support"
2145 ---help---
2146 Find out whether you have ISA slots on your motherboard. ISA is the
2147 name of a bus system, i.e. the way the CPU talks to the other stuff
2148 inside your box. Other bus systems are PCI, EISA, MicroChannel
2149 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2150 newer boards don't support it. If you have ISA, say Y, otherwise N.
2151
2152 config EISA
2153 bool "EISA support"
2154 depends on ISA
2155 ---help---
2156 The Extended Industry Standard Architecture (EISA) bus was
2157 developed as an open alternative to the IBM MicroChannel bus.
2158
2159 The EISA bus provided some of the features of the IBM MicroChannel
2160 bus while maintaining backward compatibility with cards made for
2161 the older ISA bus. The EISA bus saw limited use between 1988 and
2162 1995 when it was made obsolete by the PCI bus.
2163
2164 Say Y here if you are building a kernel for an EISA-based machine.
2165
2166 Otherwise, say N.
2167
2168 source "drivers/eisa/Kconfig"
2169
2170 config SCx200
2171 tristate "NatSemi SCx200 support"
2172 ---help---
2173 This provides basic support for National Semiconductor's
2174 (now AMD's) Geode processors. The driver probes for the
2175 PCI-IDs of several on-chip devices, so its a good dependency
2176 for other scx200_* drivers.
2177
2178 If compiled as a module, the driver is named scx200.
2179
2180 config SCx200HR_TIMER
2181 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2182 depends on SCx200
2183 default y
2184 ---help---
2185 This driver provides a clocksource built upon the on-chip
2186 27MHz high-resolution timer. Its also a workaround for
2187 NSC Geode SC-1100's buggy TSC, which loses time when the
2188 processor goes idle (as is done by the scheduler). The
2189 other workaround is idle=poll boot option.
2190
2191 config OLPC
2192 bool "One Laptop Per Child support"
2193 depends on !X86_PAE
2194 select GPIOLIB
2195 select OF
2196 select OF_PROMTREE
2197 select IRQ_DOMAIN
2198 ---help---
2199 Add support for detecting the unique features of the OLPC
2200 XO hardware.
2201
2202 config OLPC_XO1_PM
2203 bool "OLPC XO-1 Power Management"
2204 depends on OLPC && MFD_CS5535 && PM_SLEEP
2205 select MFD_CORE
2206 ---help---
2207 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2208
2209 config OLPC_XO1_RTC
2210 bool "OLPC XO-1 Real Time Clock"
2211 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2212 ---help---
2213 Add support for the XO-1 real time clock, which can be used as a
2214 programmable wakeup source.
2215
2216 config OLPC_XO1_SCI
2217 bool "OLPC XO-1 SCI extras"
2218 depends on OLPC && OLPC_XO1_PM
2219 depends on INPUT=y
2220 select POWER_SUPPLY
2221 select GPIO_CS5535
2222 select MFD_CORE
2223 ---help---
2224 Add support for SCI-based features of the OLPC XO-1 laptop:
2225 - EC-driven system wakeups
2226 - Power button
2227 - Ebook switch
2228 - Lid switch
2229 - AC adapter status updates
2230 - Battery status updates
2231
2232 config OLPC_XO15_SCI
2233 bool "OLPC XO-1.5 SCI extras"
2234 depends on OLPC && ACPI
2235 select POWER_SUPPLY
2236 ---help---
2237 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2238 - EC-driven system wakeups
2239 - AC adapter status updates
2240 - Battery status updates
2241
2242 config ALIX
2243 bool "PCEngines ALIX System Support (LED setup)"
2244 select GPIOLIB
2245 ---help---
2246 This option enables system support for the PCEngines ALIX.
2247 At present this just sets up LEDs for GPIO control on
2248 ALIX2/3/6 boards. However, other system specific setup should
2249 get added here.
2250
2251 Note: You must still enable the drivers for GPIO and LED support
2252 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2253
2254 Note: You have to set alix.force=1 for boards with Award BIOS.
2255
2256 config NET5501
2257 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2258 select GPIOLIB
2259 ---help---
2260 This option enables system support for the Soekris Engineering net5501.
2261
2262 config GEOS
2263 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2264 select GPIOLIB
2265 depends on DMI
2266 ---help---
2267 This option enables system support for the Traverse Technologies GEOS.
2268
2269 config TS5500
2270 bool "Technologic Systems TS-5500 platform support"
2271 depends on MELAN
2272 select CHECK_SIGNATURE
2273 select NEW_LEDS
2274 select LEDS_CLASS
2275 ---help---
2276 This option enables system support for the Technologic Systems TS-5500.
2277
2278 endif # X86_32
2279
2280 config AMD_NB
2281 def_bool y
2282 depends on CPU_SUP_AMD && PCI
2283
2284 source "drivers/pcmcia/Kconfig"
2285
2286 source "drivers/pci/hotplug/Kconfig"
2287
2288 config RAPIDIO
2289 tristate "RapidIO support"
2290 depends on PCI
2291 default n
2292 help
2293 If enabled this option will include drivers and the core
2294 infrastructure code to support RapidIO interconnect devices.
2295
2296 source "drivers/rapidio/Kconfig"
2297
2298 config X86_SYSFB
2299 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2300 help
2301 Firmwares often provide initial graphics framebuffers so the BIOS,
2302 bootloader or kernel can show basic video-output during boot for
2303 user-guidance and debugging. Historically, x86 used the VESA BIOS
2304 Extensions and EFI-framebuffers for this, which are mostly limited
2305 to x86.
2306 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2307 framebuffers so the new generic system-framebuffer drivers can be
2308 used on x86. If the framebuffer is not compatible with the generic
2309 modes, it is adverticed as fallback platform framebuffer so legacy
2310 drivers like efifb, vesafb and uvesafb can pick it up.
2311 If this option is not selected, all system framebuffers are always
2312 marked as fallback platform framebuffers as usual.
2313
2314 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2315 not be able to pick up generic system framebuffers if this option
2316 is selected. You are highly encouraged to enable simplefb as
2317 replacement if you select this option. simplefb can correctly deal
2318 with generic system framebuffers. But you should still keep vesafb
2319 and others enabled as fallback if a system framebuffer is
2320 incompatible with simplefb.
2321
2322 If unsure, say Y.
2323
2324 endmenu
2325
2326
2327 menu "Executable file formats / Emulations"
2328
2329 source "fs/Kconfig.binfmt"
2330
2331 config IA32_EMULATION
2332 bool "IA32 Emulation"
2333 depends on X86_64
2334 select BINFMT_ELF
2335 select COMPAT_BINFMT_ELF
2336 select HAVE_UID16
2337 ---help---
2338 Include code to run legacy 32-bit programs under a
2339 64-bit kernel. You should likely turn this on, unless you're
2340 100% sure that you don't have any 32-bit programs left.
2341
2342 config IA32_AOUT
2343 tristate "IA32 a.out support"
2344 depends on IA32_EMULATION
2345 ---help---
2346 Support old a.out binaries in the 32bit emulation.
2347
2348 config X86_X32
2349 bool "x32 ABI for 64-bit mode"
2350 depends on X86_64 && IA32_EMULATION
2351 ---help---
2352 Include code to run binaries for the x32 native 32-bit ABI
2353 for 64-bit processors. An x32 process gets access to the
2354 full 64-bit register file and wide data path while leaving
2355 pointers at 32 bits for smaller memory footprint.
2356
2357 You will need a recent binutils (2.22 or later) with
2358 elf32_x86_64 support enabled to compile a kernel with this
2359 option set.
2360
2361 config COMPAT
2362 def_bool y
2363 depends on IA32_EMULATION || X86_X32
2364 select ARCH_WANT_OLD_COMPAT_IPC
2365
2366 if COMPAT
2367 config COMPAT_FOR_U64_ALIGNMENT
2368 def_bool y
2369
2370 config SYSVIPC_COMPAT
2371 def_bool y
2372 depends on SYSVIPC
2373
2374 config KEYS_COMPAT
2375 def_bool y
2376 depends on KEYS
2377 endif
2378
2379 endmenu
2380
2381
2382 config HAVE_ATOMIC_IOMAP
2383 def_bool y
2384 depends on X86_32
2385
2386 config X86_DEV_DMA_OPS
2387 bool
2388 depends on X86_64 || STA2X11
2389
2390 config X86_DMA_REMAP
2391 bool
2392 depends on STA2X11
2393
2394 source "net/Kconfig"
2395
2396 source "drivers/Kconfig"
2397
2398 source "drivers/firmware/Kconfig"
2399
2400 source "fs/Kconfig"
2401
2402 source "arch/x86/Kconfig.debug"
2403
2404 source "security/Kconfig"
2405
2406 source "crypto/Kconfig"
2407
2408 source "arch/x86/kvm/Kconfig"
2409
2410 source "lib/Kconfig"