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