Merge branch 'pm-cpuidle'
[deliverable/linux.git] / arch / x86 / Kconfig
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_MIGHT_HAVE_ACPI_PDC if ACPI
25 select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
26 select ARCH_MIGHT_HAVE_PC_PARPORT
27 select ARCH_MIGHT_HAVE_PC_SERIO
28 select HAVE_AOUT if X86_32
29 select HAVE_UNSTABLE_SCHED_CLOCK
30 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
31 select ARCH_SUPPORTS_INT128 if X86_64
32 select ARCH_WANTS_PROT_NUMA_PROT_NONE
33 select HAVE_IDE
34 select HAVE_OPROFILE
35 select HAVE_PCSPKR_PLATFORM
36 select HAVE_PERF_EVENTS
37 select HAVE_IOREMAP_PROT
38 select HAVE_KPROBES
39 select HAVE_MEMBLOCK
40 select HAVE_MEMBLOCK_NODE_MAP
41 select ARCH_DISCARD_MEMBLOCK
42 select ARCH_WANT_OPTIONAL_GPIOLIB
43 select ARCH_WANT_FRAME_POINTERS
44 select HAVE_DMA_ATTRS
45 select HAVE_DMA_CONTIGUOUS
46 select HAVE_KRETPROBES
47 select GENERIC_EARLY_IOREMAP
48 select HAVE_OPTPROBES
49 select HAVE_KPROBES_ON_FTRACE
50 select HAVE_FTRACE_MCOUNT_RECORD
51 select HAVE_FENTRY if X86_64
52 select HAVE_C_RECORDMCOUNT
53 select HAVE_DYNAMIC_FTRACE
54 select HAVE_DYNAMIC_FTRACE_WITH_REGS
55 select HAVE_FUNCTION_TRACER
56 select HAVE_FUNCTION_GRAPH_TRACER
57 select HAVE_FUNCTION_GRAPH_FP_TEST
58 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
59 select HAVE_SYSCALL_TRACEPOINTS
60 select SYSCTL_EXCEPTION_TRACE
61 select HAVE_KVM
62 select HAVE_ARCH_KGDB
63 select HAVE_ARCH_TRACEHOOK
64 select HAVE_GENERIC_DMA_COHERENT if X86_32
65 select HAVE_EFFICIENT_UNALIGNED_ACCESS
66 select USER_STACKTRACE_SUPPORT
67 select HAVE_REGS_AND_STACK_ACCESS_API
68 select HAVE_DMA_API_DEBUG
69 select HAVE_KERNEL_GZIP
70 select HAVE_KERNEL_BZIP2
71 select HAVE_KERNEL_LZMA
72 select HAVE_KERNEL_XZ
73 select HAVE_KERNEL_LZO
74 select HAVE_KERNEL_LZ4
75 select HAVE_HW_BREAKPOINT
76 select HAVE_MIXED_BREAKPOINTS_REGS
77 select PERF_EVENTS
78 select HAVE_PERF_EVENTS_NMI
79 select HAVE_PERF_REGS
80 select HAVE_PERF_USER_STACK_DUMP
81 select HAVE_DEBUG_KMEMLEAK
82 select ANON_INODES
83 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
84 select HAVE_CMPXCHG_LOCAL
85 select HAVE_CMPXCHG_DOUBLE
86 select HAVE_ARCH_KMEMCHECK
87 select HAVE_USER_RETURN_NOTIFIER
88 select ARCH_BINFMT_ELF_RANDOMIZE_PIE
89 select HAVE_ARCH_JUMP_LABEL
90 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
91 select SPARSE_IRQ
92 select GENERIC_FIND_FIRST_BIT
93 select GENERIC_IRQ_PROBE
94 select GENERIC_PENDING_IRQ if SMP
95 select GENERIC_IRQ_SHOW
96 select GENERIC_CLOCKEVENTS_MIN_ADJUST
97 select IRQ_FORCED_THREADING
98 select HAVE_BPF_JIT if X86_64
99 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
100 select CLKEVT_I8253
101 select ARCH_HAVE_NMI_SAFE_CMPXCHG
102 select GENERIC_IOMAP
103 select DCACHE_WORD_ACCESS
104 select GENERIC_SMP_IDLE_THREAD
105 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
106 select HAVE_ARCH_SECCOMP_FILTER
107 select BUILDTIME_EXTABLE_SORT
108 select GENERIC_CMOS_UPDATE
109 select HAVE_ARCH_SOFT_DIRTY if X86_64
110 select CLOCKSOURCE_WATCHDOG
111 select GENERIC_CLOCKEVENTS
112 select ARCH_CLOCKSOURCE_DATA
113 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
114 select GENERIC_TIME_VSYSCALL
115 select KTIME_SCALAR if X86_32
116 select GENERIC_STRNCPY_FROM_USER
117 select GENERIC_STRNLEN_USER
118 select HAVE_CONTEXT_TRACKING if X86_64
119 select HAVE_IRQ_TIME_ACCOUNTING
120 select VIRT_TO_BUS
121 select MODULES_USE_ELF_REL if X86_32
122 select MODULES_USE_ELF_RELA if X86_64
123 select CLONE_BACKWARDS if X86_32
124 select ARCH_USE_BUILTIN_BSWAP
125 select ARCH_USE_QUEUE_RWLOCK
126 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
127 select OLD_SIGACTION if X86_32
128 select COMPAT_OLD_SIGACTION if IA32_EMULATION
129 select RTC_LIB
130 select HAVE_DEBUG_STACKOVERFLOW
131 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
132 select HAVE_CC_STACKPROTECTOR
133 select GENERIC_CPU_AUTOPROBE
134 select HAVE_ARCH_AUDITSYSCALL
135 select ARCH_SUPPORTS_ATOMIC_RMW
136 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
137
138 config INSTRUCTION_DECODER
139 def_bool y
140 depends on KPROBES || PERF_EVENTS || UPROBES
141
142 config OUTPUT_FORMAT
143 string
144 default "elf32-i386" if X86_32
145 default "elf64-x86-64" if X86_64
146
147 config ARCH_DEFCONFIG
148 string
149 default "arch/x86/configs/i386_defconfig" if X86_32
150 default "arch/x86/configs/x86_64_defconfig" if X86_64
151
152 config LOCKDEP_SUPPORT
153 def_bool y
154
155 config STACKTRACE_SUPPORT
156 def_bool y
157
158 config HAVE_LATENCYTOP_SUPPORT
159 def_bool y
160
161 config MMU
162 def_bool y
163
164 config SBUS
165 bool
166
167 config NEED_DMA_MAP_STATE
168 def_bool y
169 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG
170
171 config NEED_SG_DMA_LENGTH
172 def_bool y
173
174 config GENERIC_ISA_DMA
175 def_bool y
176 depends on ISA_DMA_API
177
178 config GENERIC_BUG
179 def_bool y
180 depends on BUG
181 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
182
183 config GENERIC_BUG_RELATIVE_POINTERS
184 bool
185
186 config GENERIC_HWEIGHT
187 def_bool y
188
189 config ARCH_MAY_HAVE_PC_FDC
190 def_bool y
191 depends on ISA_DMA_API
192
193 config RWSEM_XCHGADD_ALGORITHM
194 def_bool y
195
196 config GENERIC_CALIBRATE_DELAY
197 def_bool y
198
199 config ARCH_HAS_CPU_RELAX
200 def_bool y
201
202 config ARCH_HAS_CACHE_LINE_SIZE
203 def_bool y
204
205 config HAVE_SETUP_PER_CPU_AREA
206 def_bool y
207
208 config NEED_PER_CPU_EMBED_FIRST_CHUNK
209 def_bool y
210
211 config NEED_PER_CPU_PAGE_FIRST_CHUNK
212 def_bool y
213
214 config ARCH_HIBERNATION_POSSIBLE
215 def_bool y
216
217 config ARCH_SUSPEND_POSSIBLE
218 def_bool y
219
220 config ARCH_WANT_HUGE_PMD_SHARE
221 def_bool y
222
223 config ARCH_WANT_GENERAL_HUGETLB
224 def_bool y
225
226 config ZONE_DMA32
227 bool
228 default X86_64
229
230 config AUDIT_ARCH
231 bool
232 default X86_64
233
234 config ARCH_SUPPORTS_OPTIMIZED_INLINING
235 def_bool y
236
237 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
238 def_bool y
239
240 config HAVE_INTEL_TXT
241 def_bool y
242 depends on INTEL_IOMMU && ACPI
243
244 config X86_32_SMP
245 def_bool y
246 depends on X86_32 && SMP
247
248 config X86_64_SMP
249 def_bool y
250 depends on X86_64 && SMP
251
252 config X86_HT
253 def_bool y
254 depends on SMP
255
256 config X86_32_LAZY_GS
257 def_bool y
258 depends on X86_32 && !CC_STACKPROTECTOR
259
260 config ARCH_HWEIGHT_CFLAGS
261 string
262 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
263 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
264
265 config ARCH_SUPPORTS_UPROBES
266 def_bool y
267
268 config FIX_EARLYCON_MEM
269 def_bool y
270
271 source "init/Kconfig"
272 source "kernel/Kconfig.freezer"
273
274 menu "Processor type and features"
275
276 config ZONE_DMA
277 bool "DMA memory allocation support" if EXPERT
278 default y
279 help
280 DMA memory allocation support allows devices with less than 32-bit
281 addressing to allocate within the first 16MB of address space.
282 Disable if no such devices will be used.
283
284 If unsure, say Y.
285
286 config SMP
287 bool "Symmetric multi-processing support"
288 ---help---
289 This enables support for systems with more than one CPU. If you have
290 a system with only one CPU, say N. If you have a system with more
291 than one CPU, say Y.
292
293 If you say N here, the kernel will run on uni- and multiprocessor
294 machines, but will use only one CPU of a multiprocessor machine. If
295 you say Y here, the kernel will run on many, but not all,
296 uniprocessor machines. On a uniprocessor machine, the kernel
297 will run faster if you say N here.
298
299 Note that if you say Y here and choose architecture "586" or
300 "Pentium" under "Processor family", the kernel will not work on 486
301 architectures. Similarly, multiprocessor kernels for the "PPro"
302 architecture may not work on all Pentium based boards.
303
304 People using multiprocessor machines who say Y here should also say
305 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
306 Management" code will be disabled if you say Y here.
307
308 See also <file:Documentation/x86/i386/IO-APIC.txt>,
309 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
310 <http://www.tldp.org/docs.html#howto>.
311
312 If you don't know what to do here, say N.
313
314 config X86_X2APIC
315 bool "Support x2apic"
316 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
317 ---help---
318 This enables x2apic support on CPUs that have this feature.
319
320 This allows 32-bit apic IDs (so it can support very large systems),
321 and accesses the local apic via MSRs not via mmio.
322
323 If you don't know what to do here, say N.
324
325 config X86_MPPARSE
326 bool "Enable MPS table" if ACPI || SFI
327 default y
328 depends on X86_LOCAL_APIC
329 ---help---
330 For old smp systems that do not have proper acpi support. Newer systems
331 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
332
333 config X86_BIGSMP
334 bool "Support for big SMP systems with more than 8 CPUs"
335 depends on X86_32 && SMP
336 ---help---
337 This option is needed for the systems that have more than 8 CPUs
338
339 config GOLDFISH
340 def_bool y
341 depends on X86_GOLDFISH
342
343 if X86_32
344 config X86_EXTENDED_PLATFORM
345 bool "Support for extended (non-PC) x86 platforms"
346 default y
347 ---help---
348 If you disable this option then the kernel will only support
349 standard PC platforms. (which covers the vast majority of
350 systems out there.)
351
352 If you enable this option then you'll be able to select support
353 for the following (non-PC) 32 bit x86 platforms:
354 Goldfish (Android emulator)
355 AMD Elan
356 RDC R-321x SoC
357 SGI 320/540 (Visual Workstation)
358 STA2X11-based (e.g. Northville)
359 Moorestown MID devices
360
361 If you have one of these systems, or if you want to build a
362 generic distribution kernel, say Y here - otherwise say N.
363 endif
364
365 if X86_64
366 config X86_EXTENDED_PLATFORM
367 bool "Support for extended (non-PC) x86 platforms"
368 default y
369 ---help---
370 If you disable this option then the kernel will only support
371 standard PC platforms. (which covers the vast majority of
372 systems out there.)
373
374 If you enable this option then you'll be able to select support
375 for the following (non-PC) 64 bit x86 platforms:
376 Numascale NumaChip
377 ScaleMP vSMP
378 SGI Ultraviolet
379
380 If you have one of these systems, or if you want to build a
381 generic distribution kernel, say Y here - otherwise say N.
382 endif
383 # This is an alphabetically sorted list of 64 bit extended platforms
384 # Please maintain the alphabetic order if and when there are additions
385 config X86_NUMACHIP
386 bool "Numascale NumaChip"
387 depends on X86_64
388 depends on X86_EXTENDED_PLATFORM
389 depends on NUMA
390 depends on SMP
391 depends on X86_X2APIC
392 depends on PCI_MMCONFIG
393 ---help---
394 Adds support for Numascale NumaChip large-SMP systems. Needed to
395 enable more than ~168 cores.
396 If you don't have one of these, you should say N here.
397
398 config X86_VSMP
399 bool "ScaleMP vSMP"
400 select HYPERVISOR_GUEST
401 select PARAVIRT
402 depends on X86_64 && PCI
403 depends on X86_EXTENDED_PLATFORM
404 depends on SMP
405 ---help---
406 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
407 supposed to run on these EM64T-based machines. Only choose this option
408 if you have one of these machines.
409
410 config X86_UV
411 bool "SGI Ultraviolet"
412 depends on X86_64
413 depends on X86_EXTENDED_PLATFORM
414 depends on NUMA
415 depends on X86_X2APIC
416 ---help---
417 This option is needed in order to support SGI Ultraviolet systems.
418 If you don't have one of these, you should say N here.
419
420 # Following is an alphabetically sorted list of 32 bit extended platforms
421 # Please maintain the alphabetic order if and when there are additions
422
423 config X86_GOLDFISH
424 bool "Goldfish (Virtual Platform)"
425 depends on X86_EXTENDED_PLATFORM
426 ---help---
427 Enable support for the Goldfish virtual platform used primarily
428 for Android development. Unless you are building for the Android
429 Goldfish emulator say N here.
430
431 config X86_INTEL_CE
432 bool "CE4100 TV platform"
433 depends on PCI
434 depends on PCI_GODIRECT
435 depends on X86_32
436 depends on X86_EXTENDED_PLATFORM
437 select X86_REBOOTFIXUPS
438 select OF
439 select OF_EARLY_FLATTREE
440 select IRQ_DOMAIN
441 ---help---
442 Select for the Intel CE media processor (CE4100) SOC.
443 This option compiles in support for the CE4100 SOC for settop
444 boxes and media devices.
445
446 config X86_INTEL_MID
447 bool "Intel MID platform support"
448 depends on X86_32
449 depends on X86_EXTENDED_PLATFORM
450 depends on X86_PLATFORM_DEVICES
451 depends on PCI
452 depends on PCI_GOANY
453 depends on X86_IO_APIC
454 select SFI
455 select I2C
456 select DW_APB_TIMER
457 select APB_TIMER
458 select INTEL_SCU_IPC
459 select MFD_INTEL_MSIC
460 ---help---
461 Select to build a kernel capable of supporting Intel MID (Mobile
462 Internet Device) platform systems which do not have the PCI legacy
463 interfaces. If you are building for a PC class system say N here.
464
465 Intel MID platforms are based on an Intel processor and chipset which
466 consume less power than most of the x86 derivatives.
467
468 config X86_INTEL_LPSS
469 bool "Intel Low Power Subsystem Support"
470 depends on ACPI
471 select COMMON_CLK
472 select PINCTRL
473 ---help---
474 Select to build support for Intel Low Power Subsystem such as
475 found on Intel Lynxpoint PCH. Selecting this option enables
476 things like clock tree (common clock framework) and pincontrol
477 which are needed by the LPSS peripheral drivers.
478
479 config X86_RDC321X
480 bool "RDC R-321x SoC"
481 depends on X86_32
482 depends on X86_EXTENDED_PLATFORM
483 select M486
484 select X86_REBOOTFIXUPS
485 ---help---
486 This option is needed for RDC R-321x system-on-chip, also known
487 as R-8610-(G).
488 If you don't have one of these chips, you should say N here.
489
490 config X86_32_NON_STANDARD
491 bool "Support non-standard 32-bit SMP architectures"
492 depends on X86_32 && SMP
493 depends on X86_EXTENDED_PLATFORM
494 ---help---
495 This option compiles in the bigsmp and STA2X11 default
496 subarchitectures. It is intended for a generic binary
497 kernel. If you select them all, kernel will probe it one by
498 one and will fallback to default.
499
500 # Alphabetically sorted list of Non standard 32 bit platforms
501
502 config X86_SUPPORTS_MEMORY_FAILURE
503 def_bool y
504 # MCE code calls memory_failure():
505 depends on X86_MCE
506 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
507 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
508 depends on X86_64 || !SPARSEMEM
509 select ARCH_SUPPORTS_MEMORY_FAILURE
510
511 config STA2X11
512 bool "STA2X11 Companion Chip Support"
513 depends on X86_32_NON_STANDARD && PCI
514 select X86_DEV_DMA_OPS
515 select X86_DMA_REMAP
516 select SWIOTLB
517 select MFD_STA2X11
518 select ARCH_REQUIRE_GPIOLIB
519 default n
520 ---help---
521 This adds support for boards based on the STA2X11 IO-Hub,
522 a.k.a. "ConneXt". The chip is used in place of the standard
523 PC chipset, so all "standard" peripherals are missing. If this
524 option is selected the kernel will still be able to boot on
525 standard PC machines.
526
527 config X86_32_IRIS
528 tristate "Eurobraille/Iris poweroff module"
529 depends on X86_32
530 ---help---
531 The Iris machines from EuroBraille do not have APM or ACPI support
532 to shut themselves down properly. A special I/O sequence is
533 needed to do so, which is what this module does at
534 kernel shutdown.
535
536 This is only for Iris machines from EuroBraille.
537
538 If unused, say N.
539
540 config SCHED_OMIT_FRAME_POINTER
541 def_bool y
542 prompt "Single-depth WCHAN output"
543 depends on X86
544 ---help---
545 Calculate simpler /proc/<PID>/wchan values. If this option
546 is disabled then wchan values will recurse back to the
547 caller function. This provides more accurate wchan values,
548 at the expense of slightly more scheduling overhead.
549
550 If in doubt, say "Y".
551
552 menuconfig HYPERVISOR_GUEST
553 bool "Linux guest support"
554 ---help---
555 Say Y here to enable options for running Linux under various hyper-
556 visors. This option enables basic hypervisor detection and platform
557 setup.
558
559 If you say N, all options in this submenu will be skipped and
560 disabled, and Linux guest support won't be built in.
561
562 if HYPERVISOR_GUEST
563
564 config PARAVIRT
565 bool "Enable paravirtualization code"
566 ---help---
567 This changes the kernel so it can modify itself when it is run
568 under a hypervisor, potentially improving performance significantly
569 over full virtualization. However, when run without a hypervisor
570 the kernel is theoretically slower and slightly larger.
571
572 config PARAVIRT_DEBUG
573 bool "paravirt-ops debugging"
574 depends on PARAVIRT && DEBUG_KERNEL
575 ---help---
576 Enable to debug paravirt_ops internals. Specifically, BUG if
577 a paravirt_op is missing when it is called.
578
579 config PARAVIRT_SPINLOCKS
580 bool "Paravirtualization layer for spinlocks"
581 depends on PARAVIRT && SMP
582 select UNINLINE_SPIN_UNLOCK
583 ---help---
584 Paravirtualized spinlocks allow a pvops backend to replace the
585 spinlock implementation with something virtualization-friendly
586 (for example, block the virtual CPU rather than spinning).
587
588 It has a minimal impact on native kernels and gives a nice performance
589 benefit on paravirtualized KVM / Xen kernels.
590
591 If you are unsure how to answer this question, answer Y.
592
593 source "arch/x86/xen/Kconfig"
594
595 config KVM_GUEST
596 bool "KVM Guest support (including kvmclock)"
597 depends on PARAVIRT
598 select PARAVIRT_CLOCK
599 default y
600 ---help---
601 This option enables various optimizations for running under the KVM
602 hypervisor. It includes a paravirtualized clock, so that instead
603 of relying on a PIT (or probably other) emulation by the
604 underlying device model, the host provides the guest with
605 timing infrastructure such as time of day, and system time
606
607 config KVM_DEBUG_FS
608 bool "Enable debug information for KVM Guests in debugfs"
609 depends on KVM_GUEST && DEBUG_FS
610 default n
611 ---help---
612 This option enables collection of various statistics for KVM guest.
613 Statistics are displayed in debugfs filesystem. Enabling this option
614 may incur significant overhead.
615
616 source "arch/x86/lguest/Kconfig"
617
618 config PARAVIRT_TIME_ACCOUNTING
619 bool "Paravirtual steal time accounting"
620 depends on PARAVIRT
621 default n
622 ---help---
623 Select this option to enable fine granularity task steal time
624 accounting. Time spent executing other tasks in parallel with
625 the current vCPU is discounted from the vCPU power. To account for
626 that, there can be a small performance impact.
627
628 If in doubt, say N here.
629
630 config PARAVIRT_CLOCK
631 bool
632
633 endif #HYPERVISOR_GUEST
634
635 config NO_BOOTMEM
636 def_bool y
637
638 config MEMTEST
639 bool "Memtest"
640 ---help---
641 This option adds a kernel parameter 'memtest', which allows memtest
642 to be set.
643 memtest=0, mean disabled; -- default
644 memtest=1, mean do 1 test pattern;
645 ...
646 memtest=4, mean do 4 test patterns.
647 If you are unsure how to answer this question, answer N.
648
649 source "arch/x86/Kconfig.cpu"
650
651 config HPET_TIMER
652 def_bool X86_64
653 prompt "HPET Timer Support" if X86_32
654 ---help---
655 Use the IA-PC HPET (High Precision Event Timer) to manage
656 time in preference to the PIT and RTC, if a HPET is
657 present.
658 HPET is the next generation timer replacing legacy 8254s.
659 The HPET provides a stable time base on SMP
660 systems, unlike the TSC, but it is more expensive to access,
661 as it is off-chip. You can find the HPET spec at
662 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
663
664 You can safely choose Y here. However, HPET will only be
665 activated if the platform and the BIOS support this feature.
666 Otherwise the 8254 will be used for timing services.
667
668 Choose N to continue using the legacy 8254 timer.
669
670 config HPET_EMULATE_RTC
671 def_bool y
672 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
673
674 config APB_TIMER
675 def_bool y if X86_INTEL_MID
676 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
677 select DW_APB_TIMER
678 depends on X86_INTEL_MID && SFI
679 help
680 APB timer is the replacement for 8254, HPET on X86 MID platforms.
681 The APBT provides a stable time base on SMP
682 systems, unlike the TSC, but it is more expensive to access,
683 as it is off-chip. APB timers are always running regardless of CPU
684 C states, they are used as per CPU clockevent device when possible.
685
686 # Mark as expert because too many people got it wrong.
687 # The code disables itself when not needed.
688 config DMI
689 default y
690 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
691 bool "Enable DMI scanning" if EXPERT
692 ---help---
693 Enabled scanning of DMI to identify machine quirks. Say Y
694 here unless you have verified that your setup is not
695 affected by entries in the DMI blacklist. Required by PNP
696 BIOS code.
697
698 config GART_IOMMU
699 bool "Old AMD GART IOMMU support"
700 select SWIOTLB
701 depends on X86_64 && PCI && AMD_NB
702 ---help---
703 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
704 GART based hardware IOMMUs.
705
706 The GART supports full DMA access for devices with 32-bit access
707 limitations, on systems with more than 3 GB. This is usually needed
708 for USB, sound, many IDE/SATA chipsets and some other devices.
709
710 Newer systems typically have a modern AMD IOMMU, supported via
711 the CONFIG_AMD_IOMMU=y config option.
712
713 In normal configurations this driver is only active when needed:
714 there's more than 3 GB of memory and the system contains a
715 32-bit limited device.
716
717 If unsure, say Y.
718
719 config CALGARY_IOMMU
720 bool "IBM Calgary IOMMU support"
721 select SWIOTLB
722 depends on X86_64 && PCI
723 ---help---
724 Support for hardware IOMMUs in IBM's xSeries x366 and x460
725 systems. Needed to run systems with more than 3GB of memory
726 properly with 32-bit PCI devices that do not support DAC
727 (Double Address Cycle). Calgary also supports bus level
728 isolation, where all DMAs pass through the IOMMU. This
729 prevents them from going anywhere except their intended
730 destination. This catches hard-to-find kernel bugs and
731 mis-behaving drivers and devices that do not use the DMA-API
732 properly to set up their DMA buffers. The IOMMU can be
733 turned off at boot time with the iommu=off parameter.
734 Normally the kernel will make the right choice by itself.
735 If unsure, say Y.
736
737 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
738 def_bool y
739 prompt "Should Calgary be enabled by default?"
740 depends on CALGARY_IOMMU
741 ---help---
742 Should Calgary be enabled by default? if you choose 'y', Calgary
743 will be used (if it exists). If you choose 'n', Calgary will not be
744 used even if it exists. If you choose 'n' and would like to use
745 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
746 If unsure, say Y.
747
748 # need this always selected by IOMMU for the VIA workaround
749 config SWIOTLB
750 def_bool y if X86_64
751 ---help---
752 Support for software bounce buffers used on x86-64 systems
753 which don't have a hardware IOMMU. Using this PCI devices
754 which can only access 32-bits of memory can be used on systems
755 with more than 3 GB of memory.
756 If unsure, say Y.
757
758 config IOMMU_HELPER
759 def_bool y
760 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
761
762 config MAXSMP
763 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
764 depends on X86_64 && SMP && DEBUG_KERNEL
765 select CPUMASK_OFFSTACK
766 ---help---
767 Enable maximum number of CPUS and NUMA Nodes for this architecture.
768 If unsure, say N.
769
770 config NR_CPUS
771 int "Maximum number of CPUs" if SMP && !MAXSMP
772 range 2 8 if SMP && X86_32 && !X86_BIGSMP
773 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
774 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
775 default "1" if !SMP
776 default "8192" if MAXSMP
777 default "32" if SMP && X86_BIGSMP
778 default "8" if SMP
779 ---help---
780 This allows you to specify the maximum number of CPUs which this
781 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
782 supported value is 4096, otherwise the maximum value is 512. The
783 minimum value which makes sense is 2.
784
785 This is purely to save memory - each supported CPU adds
786 approximately eight kilobytes to the kernel image.
787
788 config SCHED_SMT
789 bool "SMT (Hyperthreading) scheduler support"
790 depends on X86_HT
791 ---help---
792 SMT scheduler support improves the CPU scheduler's decision making
793 when dealing with Intel Pentium 4 chips with HyperThreading at a
794 cost of slightly increased overhead in some places. If unsure say
795 N here.
796
797 config SCHED_MC
798 def_bool y
799 prompt "Multi-core scheduler support"
800 depends on X86_HT
801 ---help---
802 Multi-core scheduler support improves the CPU scheduler's decision
803 making when dealing with multi-core CPU chips at a cost of slightly
804 increased overhead in some places. If unsure say N here.
805
806 source "kernel/Kconfig.preempt"
807
808 config X86_UP_APIC
809 bool "Local APIC support on uniprocessors"
810 depends on X86_32 && !SMP && !X86_32_NON_STANDARD && !PCI_MSI
811 ---help---
812 A local APIC (Advanced Programmable Interrupt Controller) is an
813 integrated interrupt controller in the CPU. If you have a single-CPU
814 system which has a processor with a local APIC, you can say Y here to
815 enable and use it. If you say Y here even though your machine doesn't
816 have a local APIC, then the kernel will still run with no slowdown at
817 all. The local APIC supports CPU-generated self-interrupts (timer,
818 performance counters), and the NMI watchdog which detects hard
819 lockups.
820
821 config X86_UP_IOAPIC
822 bool "IO-APIC support on uniprocessors"
823 depends on X86_UP_APIC
824 ---help---
825 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
826 SMP-capable replacement for PC-style interrupt controllers. Most
827 SMP systems and many recent uniprocessor systems have one.
828
829 If you have a single-CPU system with an IO-APIC, you can say Y here
830 to use it. If you say Y here even though your machine doesn't have
831 an IO-APIC, then the kernel will still run with no slowdown at all.
832
833 config X86_LOCAL_APIC
834 def_bool y
835 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
836
837 config X86_IO_APIC
838 def_bool y
839 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC || PCI_MSI
840 select GENERIC_IRQ_LEGACY_ALLOC_HWIRQ
841
842 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
843 bool "Reroute for broken boot IRQs"
844 depends on X86_IO_APIC
845 ---help---
846 This option enables a workaround that fixes a source of
847 spurious interrupts. This is recommended when threaded
848 interrupt handling is used on systems where the generation of
849 superfluous "boot interrupts" cannot be disabled.
850
851 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
852 entry in the chipset's IO-APIC is masked (as, e.g. the RT
853 kernel does during interrupt handling). On chipsets where this
854 boot IRQ generation cannot be disabled, this workaround keeps
855 the original IRQ line masked so that only the equivalent "boot
856 IRQ" is delivered to the CPUs. The workaround also tells the
857 kernel to set up the IRQ handler on the boot IRQ line. In this
858 way only one interrupt is delivered to the kernel. Otherwise
859 the spurious second interrupt may cause the kernel to bring
860 down (vital) interrupt lines.
861
862 Only affects "broken" chipsets. Interrupt sharing may be
863 increased on these systems.
864
865 config X86_MCE
866 bool "Machine Check / overheating reporting"
867 default y
868 ---help---
869 Machine Check support allows the processor to notify the
870 kernel if it detects a problem (e.g. overheating, data corruption).
871 The action the kernel takes depends on the severity of the problem,
872 ranging from warning messages to halting the machine.
873
874 config X86_MCE_INTEL
875 def_bool y
876 prompt "Intel MCE features"
877 depends on X86_MCE && X86_LOCAL_APIC
878 ---help---
879 Additional support for intel specific MCE features such as
880 the thermal monitor.
881
882 config X86_MCE_AMD
883 def_bool y
884 prompt "AMD MCE features"
885 depends on X86_MCE && X86_LOCAL_APIC
886 ---help---
887 Additional support for AMD specific MCE features such as
888 the DRAM Error Threshold.
889
890 config X86_ANCIENT_MCE
891 bool "Support for old Pentium 5 / WinChip machine checks"
892 depends on X86_32 && X86_MCE
893 ---help---
894 Include support for machine check handling on old Pentium 5 or WinChip
895 systems. These typically need to be enabled explicitly on the command
896 line.
897
898 config X86_MCE_THRESHOLD
899 depends on X86_MCE_AMD || X86_MCE_INTEL
900 def_bool y
901
902 config X86_MCE_INJECT
903 depends on X86_MCE
904 tristate "Machine check injector support"
905 ---help---
906 Provide support for injecting machine checks for testing purposes.
907 If you don't know what a machine check is and you don't do kernel
908 QA it is safe to say n.
909
910 config X86_THERMAL_VECTOR
911 def_bool y
912 depends on X86_MCE_INTEL
913
914 config VM86
915 bool "Enable VM86 support" if EXPERT
916 default y
917 depends on X86_32
918 ---help---
919 This option is required by programs like DOSEMU to run
920 16-bit real mode legacy code on x86 processors. It also may
921 be needed by software like XFree86 to initialize some video
922 cards via BIOS. Disabling this option saves about 6K.
923
924 config X86_16BIT
925 bool "Enable support for 16-bit segments" if EXPERT
926 default y
927 ---help---
928 This option is required by programs like Wine to run 16-bit
929 protected mode legacy code on x86 processors. Disabling
930 this option saves about 300 bytes on i386, or around 6K text
931 plus 16K runtime memory on x86-64,
932
933 config X86_ESPFIX32
934 def_bool y
935 depends on X86_16BIT && X86_32
936
937 config X86_ESPFIX64
938 def_bool y
939 depends on X86_16BIT && X86_64
940
941 config TOSHIBA
942 tristate "Toshiba Laptop support"
943 depends on X86_32
944 ---help---
945 This adds a driver to safely access the System Management Mode of
946 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
947 not work on models with a Phoenix BIOS. The System Management Mode
948 is used to set the BIOS and power saving options on Toshiba portables.
949
950 For information on utilities to make use of this driver see the
951 Toshiba Linux utilities web site at:
952 <http://www.buzzard.org.uk/toshiba/>.
953
954 Say Y if you intend to run this kernel on a Toshiba portable.
955 Say N otherwise.
956
957 config I8K
958 tristate "Dell laptop support"
959 select HWMON
960 ---help---
961 This adds a driver to safely access the System Management Mode
962 of the CPU on the Dell Inspiron 8000. The System Management Mode
963 is used to read cpu temperature and cooling fan status and to
964 control the fans on the I8K portables.
965
966 This driver has been tested only on the Inspiron 8000 but it may
967 also work with other Dell laptops. You can force loading on other
968 models by passing the parameter `force=1' to the module. Use at
969 your own risk.
970
971 For information on utilities to make use of this driver see the
972 I8K Linux utilities web site at:
973 <http://people.debian.org/~dz/i8k/>
974
975 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
976 Say N otherwise.
977
978 config X86_REBOOTFIXUPS
979 bool "Enable X86 board specific fixups for reboot"
980 depends on X86_32
981 ---help---
982 This enables chipset and/or board specific fixups to be done
983 in order to get reboot to work correctly. This is only needed on
984 some combinations of hardware and BIOS. The symptom, for which
985 this config is intended, is when reboot ends with a stalled/hung
986 system.
987
988 Currently, the only fixup is for the Geode machines using
989 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
990
991 Say Y if you want to enable the fixup. Currently, it's safe to
992 enable this option even if you don't need it.
993 Say N otherwise.
994
995 config MICROCODE
996 tristate "CPU microcode loading support"
997 depends on CPU_SUP_AMD || CPU_SUP_INTEL
998 select FW_LOADER
999 ---help---
1000
1001 If you say Y here, you will be able to update the microcode on
1002 certain Intel and AMD processors. The Intel support is for the
1003 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1004 Xeon etc. The AMD support is for families 0x10 and later. You will
1005 obviously need the actual microcode binary data itself which is not
1006 shipped with the Linux kernel.
1007
1008 This option selects the general module only, you need to select
1009 at least one vendor specific module as well.
1010
1011 To compile this driver as a module, choose M here: the module
1012 will be called microcode.
1013
1014 config MICROCODE_INTEL
1015 bool "Intel microcode loading support"
1016 depends on MICROCODE
1017 default MICROCODE
1018 select FW_LOADER
1019 ---help---
1020 This options enables microcode patch loading support for Intel
1021 processors.
1022
1023 For the current Intel microcode data package go to
1024 <https://downloadcenter.intel.com> and search for
1025 'Linux Processor Microcode Data File'.
1026
1027 config MICROCODE_AMD
1028 bool "AMD microcode loading support"
1029 depends on MICROCODE
1030 select FW_LOADER
1031 ---help---
1032 If you select this option, microcode patch loading support for AMD
1033 processors will be enabled.
1034
1035 config MICROCODE_OLD_INTERFACE
1036 def_bool y
1037 depends on MICROCODE
1038
1039 config MICROCODE_INTEL_EARLY
1040 def_bool n
1041
1042 config MICROCODE_AMD_EARLY
1043 def_bool n
1044
1045 config MICROCODE_EARLY
1046 bool "Early load microcode"
1047 depends on MICROCODE=y && BLK_DEV_INITRD
1048 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL
1049 select MICROCODE_AMD_EARLY if MICROCODE_AMD
1050 default y
1051 help
1052 This option provides functionality to read additional microcode data
1053 at the beginning of initrd image. The data tells kernel to load
1054 microcode to CPU's as early as possible. No functional change if no
1055 microcode data is glued to the initrd, therefore it's safe to say Y.
1056
1057 config X86_MSR
1058 tristate "/dev/cpu/*/msr - Model-specific register support"
1059 ---help---
1060 This device gives privileged processes access to the x86
1061 Model-Specific Registers (MSRs). It is a character device with
1062 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1063 MSR accesses are directed to a specific CPU on multi-processor
1064 systems.
1065
1066 config X86_CPUID
1067 tristate "/dev/cpu/*/cpuid - CPU information support"
1068 ---help---
1069 This device gives processes access to the x86 CPUID instruction to
1070 be executed on a specific processor. It is a character device
1071 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1072 /dev/cpu/31/cpuid.
1073
1074 choice
1075 prompt "High Memory Support"
1076 default HIGHMEM4G
1077 depends on X86_32
1078
1079 config NOHIGHMEM
1080 bool "off"
1081 ---help---
1082 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1083 However, the address space of 32-bit x86 processors is only 4
1084 Gigabytes large. That means that, if you have a large amount of
1085 physical memory, not all of it can be "permanently mapped" by the
1086 kernel. The physical memory that's not permanently mapped is called
1087 "high memory".
1088
1089 If you are compiling a kernel which will never run on a machine with
1090 more than 1 Gigabyte total physical RAM, answer "off" here (default
1091 choice and suitable for most users). This will result in a "3GB/1GB"
1092 split: 3GB are mapped so that each process sees a 3GB virtual memory
1093 space and the remaining part of the 4GB virtual memory space is used
1094 by the kernel to permanently map as much physical memory as
1095 possible.
1096
1097 If the machine has between 1 and 4 Gigabytes physical RAM, then
1098 answer "4GB" here.
1099
1100 If more than 4 Gigabytes is used then answer "64GB" here. This
1101 selection turns Intel PAE (Physical Address Extension) mode on.
1102 PAE implements 3-level paging on IA32 processors. PAE is fully
1103 supported by Linux, PAE mode is implemented on all recent Intel
1104 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1105 then the kernel will not boot on CPUs that don't support PAE!
1106
1107 The actual amount of total physical memory will either be
1108 auto detected or can be forced by using a kernel command line option
1109 such as "mem=256M". (Try "man bootparam" or see the documentation of
1110 your boot loader (lilo or loadlin) about how to pass options to the
1111 kernel at boot time.)
1112
1113 If unsure, say "off".
1114
1115 config HIGHMEM4G
1116 bool "4GB"
1117 ---help---
1118 Select this if you have a 32-bit processor and between 1 and 4
1119 gigabytes of physical RAM.
1120
1121 config HIGHMEM64G
1122 bool "64GB"
1123 depends on !M486
1124 select X86_PAE
1125 ---help---
1126 Select this if you have a 32-bit processor and more than 4
1127 gigabytes of physical RAM.
1128
1129 endchoice
1130
1131 choice
1132 prompt "Memory split" if EXPERT
1133 default VMSPLIT_3G
1134 depends on X86_32
1135 ---help---
1136 Select the desired split between kernel and user memory.
1137
1138 If the address range available to the kernel is less than the
1139 physical memory installed, the remaining memory will be available
1140 as "high memory". Accessing high memory is a little more costly
1141 than low memory, as it needs to be mapped into the kernel first.
1142 Note that increasing the kernel address space limits the range
1143 available to user programs, making the address space there
1144 tighter. Selecting anything other than the default 3G/1G split
1145 will also likely make your kernel incompatible with binary-only
1146 kernel modules.
1147
1148 If you are not absolutely sure what you are doing, leave this
1149 option alone!
1150
1151 config VMSPLIT_3G
1152 bool "3G/1G user/kernel split"
1153 config VMSPLIT_3G_OPT
1154 depends on !X86_PAE
1155 bool "3G/1G user/kernel split (for full 1G low memory)"
1156 config VMSPLIT_2G
1157 bool "2G/2G user/kernel split"
1158 config VMSPLIT_2G_OPT
1159 depends on !X86_PAE
1160 bool "2G/2G user/kernel split (for full 2G low memory)"
1161 config VMSPLIT_1G
1162 bool "1G/3G user/kernel split"
1163 endchoice
1164
1165 config PAGE_OFFSET
1166 hex
1167 default 0xB0000000 if VMSPLIT_3G_OPT
1168 default 0x80000000 if VMSPLIT_2G
1169 default 0x78000000 if VMSPLIT_2G_OPT
1170 default 0x40000000 if VMSPLIT_1G
1171 default 0xC0000000
1172 depends on X86_32
1173
1174 config HIGHMEM
1175 def_bool y
1176 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1177
1178 config X86_PAE
1179 bool "PAE (Physical Address Extension) Support"
1180 depends on X86_32 && !HIGHMEM4G
1181 ---help---
1182 PAE is required for NX support, and furthermore enables
1183 larger swapspace support for non-overcommit purposes. It
1184 has the cost of more pagetable lookup overhead, and also
1185 consumes more pagetable space per process.
1186
1187 config ARCH_PHYS_ADDR_T_64BIT
1188 def_bool y
1189 depends on X86_64 || X86_PAE
1190
1191 config ARCH_DMA_ADDR_T_64BIT
1192 def_bool y
1193 depends on X86_64 || HIGHMEM64G
1194
1195 config DIRECT_GBPAGES
1196 bool "Enable 1GB pages for kernel pagetables" if EXPERT
1197 default y
1198 depends on X86_64
1199 ---help---
1200 Allow the kernel linear mapping to use 1GB pages on CPUs that
1201 support it. This can improve the kernel's performance a tiny bit by
1202 reducing TLB pressure. If in doubt, say "Y".
1203
1204 # Common NUMA Features
1205 config NUMA
1206 bool "Numa Memory Allocation and Scheduler Support"
1207 depends on SMP
1208 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1209 default y if X86_BIGSMP
1210 ---help---
1211 Enable NUMA (Non Uniform Memory Access) support.
1212
1213 The kernel will try to allocate memory used by a CPU on the
1214 local memory controller of the CPU and add some more
1215 NUMA awareness to the kernel.
1216
1217 For 64-bit this is recommended if the system is Intel Core i7
1218 (or later), AMD Opteron, or EM64T NUMA.
1219
1220 For 32-bit this is only needed if you boot a 32-bit
1221 kernel on a 64-bit NUMA platform.
1222
1223 Otherwise, you should say N.
1224
1225 config AMD_NUMA
1226 def_bool y
1227 prompt "Old style AMD Opteron NUMA detection"
1228 depends on X86_64 && NUMA && PCI
1229 ---help---
1230 Enable AMD NUMA node topology detection. You should say Y here if
1231 you have a multi processor AMD system. This uses an old method to
1232 read the NUMA configuration directly from the builtin Northbridge
1233 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1234 which also takes priority if both are compiled in.
1235
1236 config X86_64_ACPI_NUMA
1237 def_bool y
1238 prompt "ACPI NUMA detection"
1239 depends on X86_64 && NUMA && ACPI && PCI
1240 select ACPI_NUMA
1241 ---help---
1242 Enable ACPI SRAT based node topology detection.
1243
1244 # Some NUMA nodes have memory ranges that span
1245 # other nodes. Even though a pfn is valid and
1246 # between a node's start and end pfns, it may not
1247 # reside on that node. See memmap_init_zone()
1248 # for details.
1249 config NODES_SPAN_OTHER_NODES
1250 def_bool y
1251 depends on X86_64_ACPI_NUMA
1252
1253 config NUMA_EMU
1254 bool "NUMA emulation"
1255 depends on NUMA
1256 ---help---
1257 Enable NUMA emulation. A flat machine will be split
1258 into virtual nodes when booted with "numa=fake=N", where N is the
1259 number of nodes. This is only useful for debugging.
1260
1261 config NODES_SHIFT
1262 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1263 range 1 10
1264 default "10" if MAXSMP
1265 default "6" if X86_64
1266 default "3"
1267 depends on NEED_MULTIPLE_NODES
1268 ---help---
1269 Specify the maximum number of NUMA Nodes available on the target
1270 system. Increases memory reserved to accommodate various tables.
1271
1272 config ARCH_HAVE_MEMORY_PRESENT
1273 def_bool y
1274 depends on X86_32 && DISCONTIGMEM
1275
1276 config NEED_NODE_MEMMAP_SIZE
1277 def_bool y
1278 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1279
1280 config ARCH_FLATMEM_ENABLE
1281 def_bool y
1282 depends on X86_32 && !NUMA
1283
1284 config ARCH_DISCONTIGMEM_ENABLE
1285 def_bool y
1286 depends on NUMA && X86_32
1287
1288 config ARCH_DISCONTIGMEM_DEFAULT
1289 def_bool y
1290 depends on NUMA && X86_32
1291
1292 config ARCH_SPARSEMEM_ENABLE
1293 def_bool y
1294 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1295 select SPARSEMEM_STATIC if X86_32
1296 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1297
1298 config ARCH_SPARSEMEM_DEFAULT
1299 def_bool y
1300 depends on X86_64
1301
1302 config ARCH_SELECT_MEMORY_MODEL
1303 def_bool y
1304 depends on ARCH_SPARSEMEM_ENABLE
1305
1306 config ARCH_MEMORY_PROBE
1307 bool "Enable sysfs memory/probe interface"
1308 depends on X86_64 && MEMORY_HOTPLUG
1309 help
1310 This option enables a sysfs memory/probe interface for testing.
1311 See Documentation/memory-hotplug.txt for more information.
1312 If you are unsure how to answer this question, answer N.
1313
1314 config ARCH_PROC_KCORE_TEXT
1315 def_bool y
1316 depends on X86_64 && PROC_KCORE
1317
1318 config ILLEGAL_POINTER_VALUE
1319 hex
1320 default 0 if X86_32
1321 default 0xdead000000000000 if X86_64
1322
1323 source "mm/Kconfig"
1324
1325 config HIGHPTE
1326 bool "Allocate 3rd-level pagetables from highmem"
1327 depends on HIGHMEM
1328 ---help---
1329 The VM uses one page table entry for each page of physical memory.
1330 For systems with a lot of RAM, this can be wasteful of precious
1331 low memory. Setting this option will put user-space page table
1332 entries in high memory.
1333
1334 config X86_CHECK_BIOS_CORRUPTION
1335 bool "Check for low memory corruption"
1336 ---help---
1337 Periodically check for memory corruption in low memory, which
1338 is suspected to be caused by BIOS. Even when enabled in the
1339 configuration, it is disabled at runtime. Enable it by
1340 setting "memory_corruption_check=1" on the kernel command
1341 line. By default it scans the low 64k of memory every 60
1342 seconds; see the memory_corruption_check_size and
1343 memory_corruption_check_period parameters in
1344 Documentation/kernel-parameters.txt to adjust this.
1345
1346 When enabled with the default parameters, this option has
1347 almost no overhead, as it reserves a relatively small amount
1348 of memory and scans it infrequently. It both detects corruption
1349 and prevents it from affecting the running system.
1350
1351 It is, however, intended as a diagnostic tool; if repeatable
1352 BIOS-originated corruption always affects the same memory,
1353 you can use memmap= to prevent the kernel from using that
1354 memory.
1355
1356 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1357 bool "Set the default setting of memory_corruption_check"
1358 depends on X86_CHECK_BIOS_CORRUPTION
1359 default y
1360 ---help---
1361 Set whether the default state of memory_corruption_check is
1362 on or off.
1363
1364 config X86_RESERVE_LOW
1365 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1366 default 64
1367 range 4 640
1368 ---help---
1369 Specify the amount of low memory to reserve for the BIOS.
1370
1371 The first page contains BIOS data structures that the kernel
1372 must not use, so that page must always be reserved.
1373
1374 By default we reserve the first 64K of physical RAM, as a
1375 number of BIOSes are known to corrupt that memory range
1376 during events such as suspend/resume or monitor cable
1377 insertion, so it must not be used by the kernel.
1378
1379 You can set this to 4 if you are absolutely sure that you
1380 trust the BIOS to get all its memory reservations and usages
1381 right. If you know your BIOS have problems beyond the
1382 default 64K area, you can set this to 640 to avoid using the
1383 entire low memory range.
1384
1385 If you have doubts about the BIOS (e.g. suspend/resume does
1386 not work or there's kernel crashes after certain hardware
1387 hotplug events) then you might want to enable
1388 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1389 typical corruption patterns.
1390
1391 Leave this to the default value of 64 if you are unsure.
1392
1393 config MATH_EMULATION
1394 bool
1395 prompt "Math emulation" if X86_32
1396 ---help---
1397 Linux can emulate a math coprocessor (used for floating point
1398 operations) if you don't have one. 486DX and Pentium processors have
1399 a math coprocessor built in, 486SX and 386 do not, unless you added
1400 a 487DX or 387, respectively. (The messages during boot time can
1401 give you some hints here ["man dmesg"].) Everyone needs either a
1402 coprocessor or this emulation.
1403
1404 If you don't have a math coprocessor, you need to say Y here; if you
1405 say Y here even though you have a coprocessor, the coprocessor will
1406 be used nevertheless. (This behavior can be changed with the kernel
1407 command line option "no387", which comes handy if your coprocessor
1408 is broken. Try "man bootparam" or see the documentation of your boot
1409 loader (lilo or loadlin) about how to pass options to the kernel at
1410 boot time.) This means that it is a good idea to say Y here if you
1411 intend to use this kernel on different machines.
1412
1413 More information about the internals of the Linux math coprocessor
1414 emulation can be found in <file:arch/x86/math-emu/README>.
1415
1416 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1417 kernel, it won't hurt.
1418
1419 config MTRR
1420 def_bool y
1421 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1422 ---help---
1423 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1424 the Memory Type Range Registers (MTRRs) may be used to control
1425 processor access to memory ranges. This is most useful if you have
1426 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1427 allows bus write transfers to be combined into a larger transfer
1428 before bursting over the PCI/AGP bus. This can increase performance
1429 of image write operations 2.5 times or more. Saying Y here creates a
1430 /proc/mtrr file which may be used to manipulate your processor's
1431 MTRRs. Typically the X server should use this.
1432
1433 This code has a reasonably generic interface so that similar
1434 control registers on other processors can be easily supported
1435 as well:
1436
1437 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1438 Registers (ARRs) which provide a similar functionality to MTRRs. For
1439 these, the ARRs are used to emulate the MTRRs.
1440 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1441 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1442 write-combining. All of these processors are supported by this code
1443 and it makes sense to say Y here if you have one of them.
1444
1445 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1446 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1447 can lead to all sorts of problems, so it's good to say Y here.
1448
1449 You can safely say Y even if your machine doesn't have MTRRs, you'll
1450 just add about 9 KB to your kernel.
1451
1452 See <file:Documentation/x86/mtrr.txt> for more information.
1453
1454 config MTRR_SANITIZER
1455 def_bool y
1456 prompt "MTRR cleanup support"
1457 depends on MTRR
1458 ---help---
1459 Convert MTRR layout from continuous to discrete, so X drivers can
1460 add writeback entries.
1461
1462 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1463 The largest mtrr entry size for a continuous block can be set with
1464 mtrr_chunk_size.
1465
1466 If unsure, say Y.
1467
1468 config MTRR_SANITIZER_ENABLE_DEFAULT
1469 int "MTRR cleanup enable value (0-1)"
1470 range 0 1
1471 default "0"
1472 depends on MTRR_SANITIZER
1473 ---help---
1474 Enable mtrr cleanup default value
1475
1476 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1477 int "MTRR cleanup spare reg num (0-7)"
1478 range 0 7
1479 default "1"
1480 depends on MTRR_SANITIZER
1481 ---help---
1482 mtrr cleanup spare entries default, it can be changed via
1483 mtrr_spare_reg_nr=N on the kernel command line.
1484
1485 config X86_PAT
1486 def_bool y
1487 prompt "x86 PAT support" if EXPERT
1488 depends on MTRR
1489 ---help---
1490 Use PAT attributes to setup page level cache control.
1491
1492 PATs are the modern equivalents of MTRRs and are much more
1493 flexible than MTRRs.
1494
1495 Say N here if you see bootup problems (boot crash, boot hang,
1496 spontaneous reboots) or a non-working video driver.
1497
1498 If unsure, say Y.
1499
1500 config ARCH_USES_PG_UNCACHED
1501 def_bool y
1502 depends on X86_PAT
1503
1504 config ARCH_RANDOM
1505 def_bool y
1506 prompt "x86 architectural random number generator" if EXPERT
1507 ---help---
1508 Enable the x86 architectural RDRAND instruction
1509 (Intel Bull Mountain technology) to generate random numbers.
1510 If supported, this is a high bandwidth, cryptographically
1511 secure hardware random number generator.
1512
1513 config X86_SMAP
1514 def_bool y
1515 prompt "Supervisor Mode Access Prevention" if EXPERT
1516 ---help---
1517 Supervisor Mode Access Prevention (SMAP) is a security
1518 feature in newer Intel processors. There is a small
1519 performance cost if this enabled and turned on; there is
1520 also a small increase in the kernel size if this is enabled.
1521
1522 If unsure, say Y.
1523
1524 config EFI
1525 bool "EFI runtime service support"
1526 depends on ACPI
1527 select UCS2_STRING
1528 ---help---
1529 This enables the kernel to use EFI runtime services that are
1530 available (such as the EFI variable services).
1531
1532 This option is only useful on systems that have EFI firmware.
1533 In addition, you should use the latest ELILO loader available
1534 at <http://elilo.sourceforge.net> in order to take advantage
1535 of EFI runtime services. However, even with this option, the
1536 resultant kernel should continue to boot on existing non-EFI
1537 platforms.
1538
1539 config EFI_STUB
1540 bool "EFI stub support"
1541 depends on EFI
1542 ---help---
1543 This kernel feature allows a bzImage to be loaded directly
1544 by EFI firmware without the use of a bootloader.
1545
1546 See Documentation/efi-stub.txt for more information.
1547
1548 config EFI_MIXED
1549 bool "EFI mixed-mode support"
1550 depends on EFI_STUB && X86_64
1551 ---help---
1552 Enabling this feature allows a 64-bit kernel to be booted
1553 on a 32-bit firmware, provided that your CPU supports 64-bit
1554 mode.
1555
1556 Note that it is not possible to boot a mixed-mode enabled
1557 kernel via the EFI boot stub - a bootloader that supports
1558 the EFI handover protocol must be used.
1559
1560 If unsure, say N.
1561
1562 config SECCOMP
1563 def_bool y
1564 prompt "Enable seccomp to safely compute untrusted bytecode"
1565 ---help---
1566 This kernel feature is useful for number crunching applications
1567 that may need to compute untrusted bytecode during their
1568 execution. By using pipes or other transports made available to
1569 the process as file descriptors supporting the read/write
1570 syscalls, it's possible to isolate those applications in
1571 their own address space using seccomp. Once seccomp is
1572 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1573 and the task is only allowed to execute a few safe syscalls
1574 defined by each seccomp mode.
1575
1576 If unsure, say Y. Only embedded should say N here.
1577
1578 source kernel/Kconfig.hz
1579
1580 config KEXEC
1581 bool "kexec system call"
1582 ---help---
1583 kexec is a system call that implements the ability to shutdown your
1584 current kernel, and to start another kernel. It is like a reboot
1585 but it is independent of the system firmware. And like a reboot
1586 you can start any kernel with it, not just Linux.
1587
1588 The name comes from the similarity to the exec system call.
1589
1590 It is an ongoing process to be certain the hardware in a machine
1591 is properly shutdown, so do not be surprised if this code does not
1592 initially work for you. As of this writing the exact hardware
1593 interface is strongly in flux, so no good recommendation can be
1594 made.
1595
1596 config CRASH_DUMP
1597 bool "kernel crash dumps"
1598 depends on X86_64 || (X86_32 && HIGHMEM)
1599 ---help---
1600 Generate crash dump after being started by kexec.
1601 This should be normally only set in special crash dump kernels
1602 which are loaded in the main kernel with kexec-tools into
1603 a specially reserved region and then later executed after
1604 a crash by kdump/kexec. The crash dump kernel must be compiled
1605 to a memory address not used by the main kernel or BIOS using
1606 PHYSICAL_START, or it must be built as a relocatable image
1607 (CONFIG_RELOCATABLE=y).
1608 For more details see Documentation/kdump/kdump.txt
1609
1610 config KEXEC_JUMP
1611 bool "kexec jump"
1612 depends on KEXEC && HIBERNATION
1613 ---help---
1614 Jump between original kernel and kexeced kernel and invoke
1615 code in physical address mode via KEXEC
1616
1617 config PHYSICAL_START
1618 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1619 default "0x1000000"
1620 ---help---
1621 This gives the physical address where the kernel is loaded.
1622
1623 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1624 bzImage will decompress itself to above physical address and
1625 run from there. Otherwise, bzImage will run from the address where
1626 it has been loaded by the boot loader and will ignore above physical
1627 address.
1628
1629 In normal kdump cases one does not have to set/change this option
1630 as now bzImage can be compiled as a completely relocatable image
1631 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1632 address. This option is mainly useful for the folks who don't want
1633 to use a bzImage for capturing the crash dump and want to use a
1634 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1635 to be specifically compiled to run from a specific memory area
1636 (normally a reserved region) and this option comes handy.
1637
1638 So if you are using bzImage for capturing the crash dump,
1639 leave the value here unchanged to 0x1000000 and set
1640 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1641 for capturing the crash dump change this value to start of
1642 the reserved region. In other words, it can be set based on
1643 the "X" value as specified in the "crashkernel=YM@XM"
1644 command line boot parameter passed to the panic-ed
1645 kernel. Please take a look at Documentation/kdump/kdump.txt
1646 for more details about crash dumps.
1647
1648 Usage of bzImage for capturing the crash dump is recommended as
1649 one does not have to build two kernels. Same kernel can be used
1650 as production kernel and capture kernel. Above option should have
1651 gone away after relocatable bzImage support is introduced. But it
1652 is present because there are users out there who continue to use
1653 vmlinux for dump capture. This option should go away down the
1654 line.
1655
1656 Don't change this unless you know what you are doing.
1657
1658 config RELOCATABLE
1659 bool "Build a relocatable kernel"
1660 default y
1661 ---help---
1662 This builds a kernel image that retains relocation information
1663 so it can be loaded someplace besides the default 1MB.
1664 The relocations tend to make the kernel binary about 10% larger,
1665 but are discarded at runtime.
1666
1667 One use is for the kexec on panic case where the recovery kernel
1668 must live at a different physical address than the primary
1669 kernel.
1670
1671 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1672 it has been loaded at and the compile time physical address
1673 (CONFIG_PHYSICAL_START) is used as the minimum location.
1674
1675 config RANDOMIZE_BASE
1676 bool "Randomize the address of the kernel image"
1677 depends on RELOCATABLE
1678 default n
1679 ---help---
1680 Randomizes the physical and virtual address at which the
1681 kernel image is decompressed, as a security feature that
1682 deters exploit attempts relying on knowledge of the location
1683 of kernel internals.
1684
1685 Entropy is generated using the RDRAND instruction if it is
1686 supported. If RDTSC is supported, it is used as well. If
1687 neither RDRAND nor RDTSC are supported, then randomness is
1688 read from the i8254 timer.
1689
1690 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
1691 and aligned according to PHYSICAL_ALIGN. Since the kernel is
1692 built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
1693 minimum of 2MiB, only 10 bits of entropy is theoretically
1694 possible. At best, due to page table layouts, 64-bit can use
1695 9 bits of entropy and 32-bit uses 8 bits.
1696
1697 If unsure, say N.
1698
1699 config RANDOMIZE_BASE_MAX_OFFSET
1700 hex "Maximum kASLR offset allowed" if EXPERT
1701 depends on RANDOMIZE_BASE
1702 range 0x0 0x20000000 if X86_32
1703 default "0x20000000" if X86_32
1704 range 0x0 0x40000000 if X86_64
1705 default "0x40000000" if X86_64
1706 ---help---
1707 The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
1708 memory is used to determine the maximal offset in bytes that will
1709 be applied to the kernel when kernel Address Space Layout
1710 Randomization (kASLR) is active. This must be a multiple of
1711 PHYSICAL_ALIGN.
1712
1713 On 32-bit this is limited to 512MiB by page table layouts. The
1714 default is 512MiB.
1715
1716 On 64-bit this is limited by how the kernel fixmap page table is
1717 positioned, so this cannot be larger than 1GiB currently. Without
1718 RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
1719 and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
1720 modules area will shrink to compensate, up to the current maximum
1721 1GiB to 1GiB split. The default is 1GiB.
1722
1723 If unsure, leave at the default value.
1724
1725 # Relocation on x86 needs some additional build support
1726 config X86_NEED_RELOCS
1727 def_bool y
1728 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
1729
1730 config PHYSICAL_ALIGN
1731 hex "Alignment value to which kernel should be aligned"
1732 default "0x200000"
1733 range 0x2000 0x1000000 if X86_32
1734 range 0x200000 0x1000000 if X86_64
1735 ---help---
1736 This value puts the alignment restrictions on physical address
1737 where kernel is loaded and run from. Kernel is compiled for an
1738 address which meets above alignment restriction.
1739
1740 If bootloader loads the kernel at a non-aligned address and
1741 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1742 address aligned to above value and run from there.
1743
1744 If bootloader loads the kernel at a non-aligned address and
1745 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1746 load address and decompress itself to the address it has been
1747 compiled for and run from there. The address for which kernel is
1748 compiled already meets above alignment restrictions. Hence the
1749 end result is that kernel runs from a physical address meeting
1750 above alignment restrictions.
1751
1752 On 32-bit this value must be a multiple of 0x2000. On 64-bit
1753 this value must be a multiple of 0x200000.
1754
1755 Don't change this unless you know what you are doing.
1756
1757 config HOTPLUG_CPU
1758 bool "Support for hot-pluggable CPUs"
1759 depends on SMP
1760 ---help---
1761 Say Y here to allow turning CPUs off and on. CPUs can be
1762 controlled through /sys/devices/system/cpu.
1763 ( Note: power management support will enable this option
1764 automatically on SMP systems. )
1765 Say N if you want to disable CPU hotplug.
1766
1767 config BOOTPARAM_HOTPLUG_CPU0
1768 bool "Set default setting of cpu0_hotpluggable"
1769 default n
1770 depends on HOTPLUG_CPU
1771 ---help---
1772 Set whether default state of cpu0_hotpluggable is on or off.
1773
1774 Say Y here to enable CPU0 hotplug by default. If this switch
1775 is turned on, there is no need to give cpu0_hotplug kernel
1776 parameter and the CPU0 hotplug feature is enabled by default.
1777
1778 Please note: there are two known CPU0 dependencies if you want
1779 to enable the CPU0 hotplug feature either by this switch or by
1780 cpu0_hotplug kernel parameter.
1781
1782 First, resume from hibernate or suspend always starts from CPU0.
1783 So hibernate and suspend are prevented if CPU0 is offline.
1784
1785 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1786 offline if any interrupt can not migrate out of CPU0. There may
1787 be other CPU0 dependencies.
1788
1789 Please make sure the dependencies are under your control before
1790 you enable this feature.
1791
1792 Say N if you don't want to enable CPU0 hotplug feature by default.
1793 You still can enable the CPU0 hotplug feature at boot by kernel
1794 parameter cpu0_hotplug.
1795
1796 config DEBUG_HOTPLUG_CPU0
1797 def_bool n
1798 prompt "Debug CPU0 hotplug"
1799 depends on HOTPLUG_CPU
1800 ---help---
1801 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1802 soon as possible and boots up userspace with CPU0 offlined. User
1803 can online CPU0 back after boot time.
1804
1805 To debug CPU0 hotplug, you need to enable CPU0 offline/online
1806 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
1807 compilation or giving cpu0_hotplug kernel parameter at boot.
1808
1809 If unsure, say N.
1810
1811 config COMPAT_VDSO
1812 def_bool n
1813 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
1814 depends on X86_32 || IA32_EMULATION
1815 ---help---
1816 Certain buggy versions of glibc will crash if they are
1817 presented with a 32-bit vDSO that is not mapped at the address
1818 indicated in its segment table.
1819
1820 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
1821 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
1822 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
1823 the only released version with the bug, but OpenSUSE 9
1824 contains a buggy "glibc 2.3.2".
1825
1826 The symptom of the bug is that everything crashes on startup, saying:
1827 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
1828
1829 Saying Y here changes the default value of the vdso32 boot
1830 option from 1 to 0, which turns off the 32-bit vDSO entirely.
1831 This works around the glibc bug but hurts performance.
1832
1833 If unsure, say N: if you are compiling your own kernel, you
1834 are unlikely to be using a buggy version of glibc.
1835
1836 config CMDLINE_BOOL
1837 bool "Built-in kernel command line"
1838 ---help---
1839 Allow for specifying boot arguments to the kernel at
1840 build time. On some systems (e.g. embedded ones), it is
1841 necessary or convenient to provide some or all of the
1842 kernel boot arguments with the kernel itself (that is,
1843 to not rely on the boot loader to provide them.)
1844
1845 To compile command line arguments into the kernel,
1846 set this option to 'Y', then fill in the
1847 the boot arguments in CONFIG_CMDLINE.
1848
1849 Systems with fully functional boot loaders (i.e. non-embedded)
1850 should leave this option set to 'N'.
1851
1852 config CMDLINE
1853 string "Built-in kernel command string"
1854 depends on CMDLINE_BOOL
1855 default ""
1856 ---help---
1857 Enter arguments here that should be compiled into the kernel
1858 image and used at boot time. If the boot loader provides a
1859 command line at boot time, it is appended to this string to
1860 form the full kernel command line, when the system boots.
1861
1862 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1863 change this behavior.
1864
1865 In most cases, the command line (whether built-in or provided
1866 by the boot loader) should specify the device for the root
1867 file system.
1868
1869 config CMDLINE_OVERRIDE
1870 bool "Built-in command line overrides boot loader arguments"
1871 depends on CMDLINE_BOOL
1872 ---help---
1873 Set this option to 'Y' to have the kernel ignore the boot loader
1874 command line, and use ONLY the built-in command line.
1875
1876 This is used to work around broken boot loaders. This should
1877 be set to 'N' under normal conditions.
1878
1879 endmenu
1880
1881 config ARCH_ENABLE_MEMORY_HOTPLUG
1882 def_bool y
1883 depends on X86_64 || (X86_32 && HIGHMEM)
1884
1885 config ARCH_ENABLE_MEMORY_HOTREMOVE
1886 def_bool y
1887 depends on MEMORY_HOTPLUG
1888
1889 config USE_PERCPU_NUMA_NODE_ID
1890 def_bool y
1891 depends on NUMA
1892
1893 config ARCH_ENABLE_SPLIT_PMD_PTLOCK
1894 def_bool y
1895 depends on X86_64 || X86_PAE
1896
1897 config ARCH_ENABLE_HUGEPAGE_MIGRATION
1898 def_bool y
1899 depends on X86_64 && HUGETLB_PAGE && MIGRATION
1900
1901 menu "Power management and ACPI options"
1902
1903 config ARCH_HIBERNATION_HEADER
1904 def_bool y
1905 depends on X86_64 && HIBERNATION
1906
1907 source "kernel/power/Kconfig"
1908
1909 source "drivers/acpi/Kconfig"
1910
1911 source "drivers/sfi/Kconfig"
1912
1913 config X86_APM_BOOT
1914 def_bool y
1915 depends on APM
1916
1917 menuconfig APM
1918 tristate "APM (Advanced Power Management) BIOS support"
1919 depends on X86_32 && PM_SLEEP
1920 ---help---
1921 APM is a BIOS specification for saving power using several different
1922 techniques. This is mostly useful for battery powered laptops with
1923 APM compliant BIOSes. If you say Y here, the system time will be
1924 reset after a RESUME operation, the /proc/apm device will provide
1925 battery status information, and user-space programs will receive
1926 notification of APM "events" (e.g. battery status change).
1927
1928 If you select "Y" here, you can disable actual use of the APM
1929 BIOS by passing the "apm=off" option to the kernel at boot time.
1930
1931 Note that the APM support is almost completely disabled for
1932 machines with more than one CPU.
1933
1934 In order to use APM, you will need supporting software. For location
1935 and more information, read <file:Documentation/power/apm-acpi.txt>
1936 and the Battery Powered Linux mini-HOWTO, available from
1937 <http://www.tldp.org/docs.html#howto>.
1938
1939 This driver does not spin down disk drives (see the hdparm(8)
1940 manpage ("man 8 hdparm") for that), and it doesn't turn off
1941 VESA-compliant "green" monitors.
1942
1943 This driver does not support the TI 4000M TravelMate and the ACER
1944 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1945 desktop machines also don't have compliant BIOSes, and this driver
1946 may cause those machines to panic during the boot phase.
1947
1948 Generally, if you don't have a battery in your machine, there isn't
1949 much point in using this driver and you should say N. If you get
1950 random kernel OOPSes or reboots that don't seem to be related to
1951 anything, try disabling/enabling this option (or disabling/enabling
1952 APM in your BIOS).
1953
1954 Some other things you should try when experiencing seemingly random,
1955 "weird" problems:
1956
1957 1) make sure that you have enough swap space and that it is
1958 enabled.
1959 2) pass the "no-hlt" option to the kernel
1960 3) switch on floating point emulation in the kernel and pass
1961 the "no387" option to the kernel
1962 4) pass the "floppy=nodma" option to the kernel
1963 5) pass the "mem=4M" option to the kernel (thereby disabling
1964 all but the first 4 MB of RAM)
1965 6) make sure that the CPU is not over clocked.
1966 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1967 8) disable the cache from your BIOS settings
1968 9) install a fan for the video card or exchange video RAM
1969 10) install a better fan for the CPU
1970 11) exchange RAM chips
1971 12) exchange the motherboard.
1972
1973 To compile this driver as a module, choose M here: the
1974 module will be called apm.
1975
1976 if APM
1977
1978 config APM_IGNORE_USER_SUSPEND
1979 bool "Ignore USER SUSPEND"
1980 ---help---
1981 This option will ignore USER SUSPEND requests. On machines with a
1982 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1983 series notebooks, it is necessary to say Y because of a BIOS bug.
1984
1985 config APM_DO_ENABLE
1986 bool "Enable PM at boot time"
1987 ---help---
1988 Enable APM features at boot time. From page 36 of the APM BIOS
1989 specification: "When disabled, the APM BIOS does not automatically
1990 power manage devices, enter the Standby State, enter the Suspend
1991 State, or take power saving steps in response to CPU Idle calls."
1992 This driver will make CPU Idle calls when Linux is idle (unless this
1993 feature is turned off -- see "Do CPU IDLE calls", below). This
1994 should always save battery power, but more complicated APM features
1995 will be dependent on your BIOS implementation. You may need to turn
1996 this option off if your computer hangs at boot time when using APM
1997 support, or if it beeps continuously instead of suspending. Turn
1998 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1999 T400CDT. This is off by default since most machines do fine without
2000 this feature.
2001
2002 config APM_CPU_IDLE
2003 depends on CPU_IDLE
2004 bool "Make CPU Idle calls when idle"
2005 ---help---
2006 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2007 On some machines, this can activate improved power savings, such as
2008 a slowed CPU clock rate, when the machine is idle. These idle calls
2009 are made after the idle loop has run for some length of time (e.g.,
2010 333 mS). On some machines, this will cause a hang at boot time or
2011 whenever the CPU becomes idle. (On machines with more than one CPU,
2012 this option does nothing.)
2013
2014 config APM_DISPLAY_BLANK
2015 bool "Enable console blanking using APM"
2016 ---help---
2017 Enable console blanking using the APM. Some laptops can use this to
2018 turn off the LCD backlight when the screen blanker of the Linux
2019 virtual console blanks the screen. Note that this is only used by
2020 the virtual console screen blanker, and won't turn off the backlight
2021 when using the X Window system. This also doesn't have anything to
2022 do with your VESA-compliant power-saving monitor. Further, this
2023 option doesn't work for all laptops -- it might not turn off your
2024 backlight at all, or it might print a lot of errors to the console,
2025 especially if you are using gpm.
2026
2027 config APM_ALLOW_INTS
2028 bool "Allow interrupts during APM BIOS calls"
2029 ---help---
2030 Normally we disable external interrupts while we are making calls to
2031 the APM BIOS as a measure to lessen the effects of a badly behaving
2032 BIOS implementation. The BIOS should reenable interrupts if it
2033 needs to. Unfortunately, some BIOSes do not -- especially those in
2034 many of the newer IBM Thinkpads. If you experience hangs when you
2035 suspend, try setting this to Y. Otherwise, say N.
2036
2037 endif # APM
2038
2039 source "drivers/cpufreq/Kconfig"
2040
2041 source "drivers/cpuidle/Kconfig"
2042
2043 source "drivers/idle/Kconfig"
2044
2045 endmenu
2046
2047
2048 menu "Bus options (PCI etc.)"
2049
2050 config PCI
2051 bool "PCI support"
2052 default y
2053 ---help---
2054 Find out whether you have a PCI motherboard. PCI is the name of a
2055 bus system, i.e. the way the CPU talks to the other stuff inside
2056 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2057 VESA. If you have PCI, say Y, otherwise N.
2058
2059 choice
2060 prompt "PCI access mode"
2061 depends on X86_32 && PCI
2062 default PCI_GOANY
2063 ---help---
2064 On PCI systems, the BIOS can be used to detect the PCI devices and
2065 determine their configuration. However, some old PCI motherboards
2066 have BIOS bugs and may crash if this is done. Also, some embedded
2067 PCI-based systems don't have any BIOS at all. Linux can also try to
2068 detect the PCI hardware directly without using the BIOS.
2069
2070 With this option, you can specify how Linux should detect the
2071 PCI devices. If you choose "BIOS", the BIOS will be used,
2072 if you choose "Direct", the BIOS won't be used, and if you
2073 choose "MMConfig", then PCI Express MMCONFIG will be used.
2074 If you choose "Any", the kernel will try MMCONFIG, then the
2075 direct access method and falls back to the BIOS if that doesn't
2076 work. If unsure, go with the default, which is "Any".
2077
2078 config PCI_GOBIOS
2079 bool "BIOS"
2080
2081 config PCI_GOMMCONFIG
2082 bool "MMConfig"
2083
2084 config PCI_GODIRECT
2085 bool "Direct"
2086
2087 config PCI_GOOLPC
2088 bool "OLPC XO-1"
2089 depends on OLPC
2090
2091 config PCI_GOANY
2092 bool "Any"
2093
2094 endchoice
2095
2096 config PCI_BIOS
2097 def_bool y
2098 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2099
2100 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2101 config PCI_DIRECT
2102 def_bool y
2103 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2104
2105 config PCI_MMCONFIG
2106 def_bool y
2107 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2108
2109 config PCI_OLPC
2110 def_bool y
2111 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2112
2113 config PCI_XEN
2114 def_bool y
2115 depends on PCI && XEN
2116 select SWIOTLB_XEN
2117
2118 config PCI_DOMAINS
2119 def_bool y
2120 depends on PCI
2121
2122 config PCI_MMCONFIG
2123 bool "Support mmconfig PCI config space access"
2124 depends on X86_64 && PCI && ACPI
2125
2126 config PCI_CNB20LE_QUIRK
2127 bool "Read CNB20LE Host Bridge Windows" if EXPERT
2128 depends on PCI
2129 help
2130 Read the PCI windows out of the CNB20LE host bridge. This allows
2131 PCI hotplug to work on systems with the CNB20LE chipset which do
2132 not have ACPI.
2133
2134 There's no public spec for this chipset, and this functionality
2135 is known to be incomplete.
2136
2137 You should say N unless you know you need this.
2138
2139 source "drivers/pci/pcie/Kconfig"
2140
2141 source "drivers/pci/Kconfig"
2142
2143 # x86_64 have no ISA slots, but can have ISA-style DMA.
2144 config ISA_DMA_API
2145 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2146 default y
2147 help
2148 Enables ISA-style DMA support for devices requiring such controllers.
2149 If unsure, say Y.
2150
2151 if X86_32
2152
2153 config ISA
2154 bool "ISA support"
2155 ---help---
2156 Find out whether you have ISA slots on your motherboard. ISA is the
2157 name of a bus system, i.e. the way the CPU talks to the other stuff
2158 inside your box. Other bus systems are PCI, EISA, MicroChannel
2159 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2160 newer boards don't support it. If you have ISA, say Y, otherwise N.
2161
2162 config EISA
2163 bool "EISA support"
2164 depends on ISA
2165 ---help---
2166 The Extended Industry Standard Architecture (EISA) bus was
2167 developed as an open alternative to the IBM MicroChannel bus.
2168
2169 The EISA bus provided some of the features of the IBM MicroChannel
2170 bus while maintaining backward compatibility with cards made for
2171 the older ISA bus. The EISA bus saw limited use between 1988 and
2172 1995 when it was made obsolete by the PCI bus.
2173
2174 Say Y here if you are building a kernel for an EISA-based machine.
2175
2176 Otherwise, say N.
2177
2178 source "drivers/eisa/Kconfig"
2179
2180 config SCx200
2181 tristate "NatSemi SCx200 support"
2182 ---help---
2183 This provides basic support for National Semiconductor's
2184 (now AMD's) Geode processors. The driver probes for the
2185 PCI-IDs of several on-chip devices, so its a good dependency
2186 for other scx200_* drivers.
2187
2188 If compiled as a module, the driver is named scx200.
2189
2190 config SCx200HR_TIMER
2191 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2192 depends on SCx200
2193 default y
2194 ---help---
2195 This driver provides a clocksource built upon the on-chip
2196 27MHz high-resolution timer. Its also a workaround for
2197 NSC Geode SC-1100's buggy TSC, which loses time when the
2198 processor goes idle (as is done by the scheduler). The
2199 other workaround is idle=poll boot option.
2200
2201 config OLPC
2202 bool "One Laptop Per Child support"
2203 depends on !X86_PAE
2204 select GPIOLIB
2205 select OF
2206 select OF_PROMTREE
2207 select IRQ_DOMAIN
2208 ---help---
2209 Add support for detecting the unique features of the OLPC
2210 XO hardware.
2211
2212 config OLPC_XO1_PM
2213 bool "OLPC XO-1 Power Management"
2214 depends on OLPC && MFD_CS5535 && PM_SLEEP
2215 select MFD_CORE
2216 ---help---
2217 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2218
2219 config OLPC_XO1_RTC
2220 bool "OLPC XO-1 Real Time Clock"
2221 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2222 ---help---
2223 Add support for the XO-1 real time clock, which can be used as a
2224 programmable wakeup source.
2225
2226 config OLPC_XO1_SCI
2227 bool "OLPC XO-1 SCI extras"
2228 depends on OLPC && OLPC_XO1_PM
2229 depends on INPUT=y
2230 select POWER_SUPPLY
2231 select GPIO_CS5535
2232 select MFD_CORE
2233 ---help---
2234 Add support for SCI-based features of the OLPC XO-1 laptop:
2235 - EC-driven system wakeups
2236 - Power button
2237 - Ebook switch
2238 - Lid switch
2239 - AC adapter status updates
2240 - Battery status updates
2241
2242 config OLPC_XO15_SCI
2243 bool "OLPC XO-1.5 SCI extras"
2244 depends on OLPC && ACPI
2245 select POWER_SUPPLY
2246 ---help---
2247 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2248 - EC-driven system wakeups
2249 - AC adapter status updates
2250 - Battery status updates
2251
2252 config ALIX
2253 bool "PCEngines ALIX System Support (LED setup)"
2254 select GPIOLIB
2255 ---help---
2256 This option enables system support for the PCEngines ALIX.
2257 At present this just sets up LEDs for GPIO control on
2258 ALIX2/3/6 boards. However, other system specific setup should
2259 get added here.
2260
2261 Note: You must still enable the drivers for GPIO and LED support
2262 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2263
2264 Note: You have to set alix.force=1 for boards with Award BIOS.
2265
2266 config NET5501
2267 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2268 select GPIOLIB
2269 ---help---
2270 This option enables system support for the Soekris Engineering net5501.
2271
2272 config GEOS
2273 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2274 select GPIOLIB
2275 depends on DMI
2276 ---help---
2277 This option enables system support for the Traverse Technologies GEOS.
2278
2279 config TS5500
2280 bool "Technologic Systems TS-5500 platform support"
2281 depends on MELAN
2282 select CHECK_SIGNATURE
2283 select NEW_LEDS
2284 select LEDS_CLASS
2285 ---help---
2286 This option enables system support for the Technologic Systems TS-5500.
2287
2288 endif # X86_32
2289
2290 config AMD_NB
2291 def_bool y
2292 depends on CPU_SUP_AMD && PCI
2293
2294 source "drivers/pcmcia/Kconfig"
2295
2296 source "drivers/pci/hotplug/Kconfig"
2297
2298 config RAPIDIO
2299 tristate "RapidIO support"
2300 depends on PCI
2301 default n
2302 help
2303 If enabled this option will include drivers and the core
2304 infrastructure code to support RapidIO interconnect devices.
2305
2306 source "drivers/rapidio/Kconfig"
2307
2308 config X86_SYSFB
2309 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2310 help
2311 Firmwares often provide initial graphics framebuffers so the BIOS,
2312 bootloader or kernel can show basic video-output during boot for
2313 user-guidance and debugging. Historically, x86 used the VESA BIOS
2314 Extensions and EFI-framebuffers for this, which are mostly limited
2315 to x86.
2316 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2317 framebuffers so the new generic system-framebuffer drivers can be
2318 used on x86. If the framebuffer is not compatible with the generic
2319 modes, it is adverticed as fallback platform framebuffer so legacy
2320 drivers like efifb, vesafb and uvesafb can pick it up.
2321 If this option is not selected, all system framebuffers are always
2322 marked as fallback platform framebuffers as usual.
2323
2324 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2325 not be able to pick up generic system framebuffers if this option
2326 is selected. You are highly encouraged to enable simplefb as
2327 replacement if you select this option. simplefb can correctly deal
2328 with generic system framebuffers. But you should still keep vesafb
2329 and others enabled as fallback if a system framebuffer is
2330 incompatible with simplefb.
2331
2332 If unsure, say Y.
2333
2334 endmenu
2335
2336
2337 menu "Executable file formats / Emulations"
2338
2339 source "fs/Kconfig.binfmt"
2340
2341 config IA32_EMULATION
2342 bool "IA32 Emulation"
2343 depends on X86_64
2344 select BINFMT_ELF
2345 select COMPAT_BINFMT_ELF
2346 select HAVE_UID16
2347 ---help---
2348 Include code to run legacy 32-bit programs under a
2349 64-bit kernel. You should likely turn this on, unless you're
2350 100% sure that you don't have any 32-bit programs left.
2351
2352 config IA32_AOUT
2353 tristate "IA32 a.out support"
2354 depends on IA32_EMULATION
2355 ---help---
2356 Support old a.out binaries in the 32bit emulation.
2357
2358 config X86_X32
2359 bool "x32 ABI for 64-bit mode"
2360 depends on X86_64 && IA32_EMULATION
2361 ---help---
2362 Include code to run binaries for the x32 native 32-bit ABI
2363 for 64-bit processors. An x32 process gets access to the
2364 full 64-bit register file and wide data path while leaving
2365 pointers at 32 bits for smaller memory footprint.
2366
2367 You will need a recent binutils (2.22 or later) with
2368 elf32_x86_64 support enabled to compile a kernel with this
2369 option set.
2370
2371 config COMPAT
2372 def_bool y
2373 depends on IA32_EMULATION || X86_X32
2374 select ARCH_WANT_OLD_COMPAT_IPC
2375
2376 if COMPAT
2377 config COMPAT_FOR_U64_ALIGNMENT
2378 def_bool y
2379
2380 config SYSVIPC_COMPAT
2381 def_bool y
2382 depends on SYSVIPC
2383
2384 config KEYS_COMPAT
2385 def_bool y
2386 depends on KEYS
2387 endif
2388
2389 endmenu
2390
2391
2392 config HAVE_ATOMIC_IOMAP
2393 def_bool y
2394 depends on X86_32
2395
2396 config X86_DEV_DMA_OPS
2397 bool
2398 depends on X86_64 || STA2X11
2399
2400 config X86_DMA_REMAP
2401 bool
2402 depends on STA2X11
2403
2404 config IOSF_MBI
2405 tristate
2406 default m
2407 depends on PCI
2408
2409 source "net/Kconfig"
2410
2411 source "drivers/Kconfig"
2412
2413 source "drivers/firmware/Kconfig"
2414
2415 source "fs/Kconfig"
2416
2417 source "arch/x86/Kconfig.debug"
2418
2419 source "security/Kconfig"
2420
2421 source "crypto/Kconfig"
2422
2423 source "arch/x86/kvm/Kconfig"
2424
2425 source "lib/Kconfig"
This page took 0.078 seconds and 6 git commands to generate.