Merge tag 'stable/for-linus-3.8-rc0-tag' of git://git.kernel.org/pub/scm/linux/kernel...
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / x86 / Kconfig
1 # Select 32 or 64 bit
2 config 64BIT
3 bool "64-bit kernel" if ARCH = "x86"
4 default ARCH = "x86_64"
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 HAVE_AOUT if X86_32
24 select HAVE_UNSTABLE_SCHED_CLOCK
25 select ARCH_SUPPORTS_NUMA_BALANCING
26 select ARCH_WANTS_PROT_NUMA_PROT_NONE
27 select HAVE_IDE
28 select HAVE_OPROFILE
29 select HAVE_PCSPKR_PLATFORM
30 select HAVE_PERF_EVENTS
31 select HAVE_IRQ_WORK
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_FTRACE_MCOUNT_RECORD
44 select HAVE_FENTRY if X86_64
45 select HAVE_C_RECORDMCOUNT
46 select HAVE_DYNAMIC_FTRACE
47 select HAVE_FUNCTION_TRACER
48 select HAVE_FUNCTION_GRAPH_TRACER
49 select HAVE_FUNCTION_GRAPH_FP_TEST
50 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
51 select HAVE_SYSCALL_TRACEPOINTS
52 select SYSCTL_EXCEPTION_TRACE
53 select HAVE_KVM
54 select HAVE_ARCH_KGDB
55 select HAVE_ARCH_TRACEHOOK
56 select HAVE_GENERIC_DMA_COHERENT if X86_32
57 select HAVE_EFFICIENT_UNALIGNED_ACCESS
58 select USER_STACKTRACE_SUPPORT
59 select HAVE_REGS_AND_STACK_ACCESS_API
60 select HAVE_DMA_API_DEBUG
61 select HAVE_KERNEL_GZIP
62 select HAVE_KERNEL_BZIP2
63 select HAVE_KERNEL_LZMA
64 select HAVE_KERNEL_XZ
65 select HAVE_KERNEL_LZO
66 select HAVE_HW_BREAKPOINT
67 select HAVE_MIXED_BREAKPOINTS_REGS
68 select PERF_EVENTS
69 select HAVE_PERF_EVENTS_NMI
70 select HAVE_PERF_REGS
71 select HAVE_PERF_USER_STACK_DUMP
72 select HAVE_DEBUG_KMEMLEAK
73 select ANON_INODES
74 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
75 select HAVE_CMPXCHG_LOCAL
76 select HAVE_CMPXCHG_DOUBLE
77 select HAVE_ARCH_KMEMCHECK
78 select HAVE_USER_RETURN_NOTIFIER
79 select ARCH_BINFMT_ELF_RANDOMIZE_PIE
80 select HAVE_ARCH_JUMP_LABEL
81 select HAVE_TEXT_POKE_SMP
82 select HAVE_GENERIC_HARDIRQS
83 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
84 select SPARSE_IRQ
85 select GENERIC_FIND_FIRST_BIT
86 select GENERIC_IRQ_PROBE
87 select GENERIC_PENDING_IRQ if SMP
88 select GENERIC_IRQ_SHOW
89 select GENERIC_CLOCKEVENTS_MIN_ADJUST
90 select IRQ_FORCED_THREADING
91 select USE_GENERIC_SMP_HELPERS if SMP
92 select HAVE_BPF_JIT if X86_64
93 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
94 select CLKEVT_I8253
95 select ARCH_HAVE_NMI_SAFE_CMPXCHG
96 select GENERIC_IOMAP
97 select DCACHE_WORD_ACCESS
98 select GENERIC_SMP_IDLE_THREAD
99 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
100 select HAVE_ARCH_SECCOMP_FILTER
101 select BUILDTIME_EXTABLE_SORT
102 select GENERIC_CMOS_UPDATE
103 select CLOCKSOURCE_WATCHDOG
104 select GENERIC_CLOCKEVENTS
105 select ARCH_CLOCKSOURCE_DATA if X86_64
106 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
107 select GENERIC_TIME_VSYSCALL if X86_64
108 select KTIME_SCALAR if X86_32
109 select GENERIC_STRNCPY_FROM_USER
110 select GENERIC_STRNLEN_USER
111 select HAVE_CONTEXT_TRACKING if X86_64
112 select HAVE_IRQ_TIME_ACCOUNTING
113 select GENERIC_KERNEL_THREAD
114 select GENERIC_KERNEL_EXECVE
115 select MODULES_USE_ELF_REL if X86_32
116 select MODULES_USE_ELF_RELA if X86_64
117 select CLONE_BACKWARDS if X86_32
118
119 config INSTRUCTION_DECODER
120 def_bool y
121 depends on KPROBES || PERF_EVENTS || UPROBES
122
123 config OUTPUT_FORMAT
124 string
125 default "elf32-i386" if X86_32
126 default "elf64-x86-64" if X86_64
127
128 config ARCH_DEFCONFIG
129 string
130 default "arch/x86/configs/i386_defconfig" if X86_32
131 default "arch/x86/configs/x86_64_defconfig" if X86_64
132
133 config LOCKDEP_SUPPORT
134 def_bool y
135
136 config STACKTRACE_SUPPORT
137 def_bool y
138
139 config HAVE_LATENCYTOP_SUPPORT
140 def_bool y
141
142 config MMU
143 def_bool y
144
145 config SBUS
146 bool
147
148 config NEED_DMA_MAP_STATE
149 def_bool y
150 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG
151
152 config NEED_SG_DMA_LENGTH
153 def_bool y
154
155 config GENERIC_ISA_DMA
156 def_bool y
157 depends on ISA_DMA_API
158
159 config GENERIC_BUG
160 def_bool y
161 depends on BUG
162 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
163
164 config GENERIC_BUG_RELATIVE_POINTERS
165 bool
166
167 config GENERIC_HWEIGHT
168 def_bool y
169
170 config GENERIC_GPIO
171 bool
172
173 config ARCH_MAY_HAVE_PC_FDC
174 def_bool y
175 depends on ISA_DMA_API
176
177 config RWSEM_XCHGADD_ALGORITHM
178 def_bool y
179
180 config GENERIC_CALIBRATE_DELAY
181 def_bool y
182
183 config ARCH_HAS_CPU_RELAX
184 def_bool y
185
186 config ARCH_HAS_DEFAULT_IDLE
187 def_bool y
188
189 config ARCH_HAS_CACHE_LINE_SIZE
190 def_bool y
191
192 config ARCH_HAS_CPU_AUTOPROBE
193 def_bool y
194
195 config HAVE_SETUP_PER_CPU_AREA
196 def_bool y
197
198 config NEED_PER_CPU_EMBED_FIRST_CHUNK
199 def_bool y
200
201 config NEED_PER_CPU_PAGE_FIRST_CHUNK
202 def_bool y
203
204 config ARCH_HIBERNATION_POSSIBLE
205 def_bool y
206
207 config ARCH_SUSPEND_POSSIBLE
208 def_bool y
209
210 config ZONE_DMA32
211 bool
212 default X86_64
213
214 config AUDIT_ARCH
215 bool
216 default X86_64
217
218 config ARCH_SUPPORTS_OPTIMIZED_INLINING
219 def_bool y
220
221 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
222 def_bool y
223
224 config HAVE_INTEL_TXT
225 def_bool y
226 depends on EXPERIMENTAL && INTEL_IOMMU && ACPI
227
228 config X86_32_SMP
229 def_bool y
230 depends on X86_32 && SMP
231
232 config X86_64_SMP
233 def_bool y
234 depends on X86_64 && SMP
235
236 config X86_HT
237 def_bool y
238 depends on SMP
239
240 config X86_32_LAZY_GS
241 def_bool y
242 depends on X86_32 && !CC_STACKPROTECTOR
243
244 config ARCH_HWEIGHT_CFLAGS
245 string
246 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
247 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
248
249 config ARCH_CPU_PROBE_RELEASE
250 def_bool y
251 depends on HOTPLUG_CPU
252
253 config ARCH_SUPPORTS_UPROBES
254 def_bool y
255
256 source "init/Kconfig"
257 source "kernel/Kconfig.freezer"
258
259 menu "Processor type and features"
260
261 config ZONE_DMA
262 bool "DMA memory allocation support" if EXPERT
263 default y
264 help
265 DMA memory allocation support allows devices with less than 32-bit
266 addressing to allocate within the first 16MB of address space.
267 Disable if no such devices will be used.
268
269 If unsure, say Y.
270
271 config SMP
272 bool "Symmetric multi-processing support"
273 ---help---
274 This enables support for systems with more than one CPU. If you have
275 a system with only one CPU, like most personal computers, say N. If
276 you have a system with more than one CPU, say Y.
277
278 If you say N here, the kernel will run on single and multiprocessor
279 machines, but will use only one CPU of a multiprocessor machine. If
280 you say Y here, the kernel will run on many, but not all,
281 singleprocessor machines. On a singleprocessor machine, the kernel
282 will run faster if you say N here.
283
284 Note that if you say Y here and choose architecture "586" or
285 "Pentium" under "Processor family", the kernel will not work on 486
286 architectures. Similarly, multiprocessor kernels for the "PPro"
287 architecture may not work on all Pentium based boards.
288
289 People using multiprocessor machines who say Y here should also say
290 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
291 Management" code will be disabled if you say Y here.
292
293 See also <file:Documentation/x86/i386/IO-APIC.txt>,
294 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
295 <http://www.tldp.org/docs.html#howto>.
296
297 If you don't know what to do here, say N.
298
299 config X86_X2APIC
300 bool "Support x2apic"
301 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
302 ---help---
303 This enables x2apic support on CPUs that have this feature.
304
305 This allows 32-bit apic IDs (so it can support very large systems),
306 and accesses the local apic via MSRs not via mmio.
307
308 If you don't know what to do here, say N.
309
310 config X86_MPPARSE
311 bool "Enable MPS table" if ACPI || SFI
312 default y
313 depends on X86_LOCAL_APIC
314 ---help---
315 For old smp systems that do not have proper acpi support. Newer systems
316 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
317
318 config X86_BIGSMP
319 bool "Support for big SMP systems with more than 8 CPUs"
320 depends on X86_32 && SMP
321 ---help---
322 This option is needed for the systems that have more than 8 CPUs
323
324 if X86_32
325 config X86_EXTENDED_PLATFORM
326 bool "Support for extended (non-PC) x86 platforms"
327 default y
328 ---help---
329 If you disable this option then the kernel will only support
330 standard PC platforms. (which covers the vast majority of
331 systems out there.)
332
333 If you enable this option then you'll be able to select support
334 for the following (non-PC) 32 bit x86 platforms:
335 AMD Elan
336 NUMAQ (IBM/Sequent)
337 RDC R-321x SoC
338 SGI 320/540 (Visual Workstation)
339 STA2X11-based (e.g. Northville)
340 Summit/EXA (IBM x440)
341 Unisys ES7000 IA32 series
342 Moorestown MID devices
343
344 If you have one of these systems, or if you want to build a
345 generic distribution kernel, say Y here - otherwise say N.
346 endif
347
348 if X86_64
349 config X86_EXTENDED_PLATFORM
350 bool "Support for extended (non-PC) x86 platforms"
351 default y
352 ---help---
353 If you disable this option then the kernel will only support
354 standard PC platforms. (which covers the vast majority of
355 systems out there.)
356
357 If you enable this option then you'll be able to select support
358 for the following (non-PC) 64 bit x86 platforms:
359 Numascale NumaChip
360 ScaleMP vSMP
361 SGI Ultraviolet
362
363 If you have one of these systems, or if you want to build a
364 generic distribution kernel, say Y here - otherwise say N.
365 endif
366 # This is an alphabetically sorted list of 64 bit extended platforms
367 # Please maintain the alphabetic order if and when there are additions
368 config X86_NUMACHIP
369 bool "Numascale NumaChip"
370 depends on X86_64
371 depends on X86_EXTENDED_PLATFORM
372 depends on NUMA
373 depends on SMP
374 depends on X86_X2APIC
375 depends on PCI_MMCONFIG
376 ---help---
377 Adds support for Numascale NumaChip large-SMP systems. Needed to
378 enable more than ~168 cores.
379 If you don't have one of these, you should say N here.
380
381 config X86_VSMP
382 bool "ScaleMP vSMP"
383 select PARAVIRT_GUEST
384 select PARAVIRT
385 depends on X86_64 && PCI
386 depends on X86_EXTENDED_PLATFORM
387 depends on SMP
388 ---help---
389 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
390 supposed to run on these EM64T-based machines. Only choose this option
391 if you have one of these machines.
392
393 config X86_UV
394 bool "SGI Ultraviolet"
395 depends on X86_64
396 depends on X86_EXTENDED_PLATFORM
397 depends on NUMA
398 depends on X86_X2APIC
399 ---help---
400 This option is needed in order to support SGI Ultraviolet systems.
401 If you don't have one of these, you should say N here.
402
403 # Following is an alphabetically sorted list of 32 bit extended platforms
404 # Please maintain the alphabetic order if and when there are additions
405
406 config X86_INTEL_CE
407 bool "CE4100 TV platform"
408 depends on PCI
409 depends on PCI_GODIRECT
410 depends on X86_32
411 depends on X86_EXTENDED_PLATFORM
412 select X86_REBOOTFIXUPS
413 select OF
414 select OF_EARLY_FLATTREE
415 select IRQ_DOMAIN
416 ---help---
417 Select for the Intel CE media processor (CE4100) SOC.
418 This option compiles in support for the CE4100 SOC for settop
419 boxes and media devices.
420
421 config X86_WANT_INTEL_MID
422 bool "Intel MID platform support"
423 depends on X86_32
424 depends on X86_EXTENDED_PLATFORM
425 ---help---
426 Select to build a kernel capable of supporting Intel MID platform
427 systems which do not have the PCI legacy interfaces (Moorestown,
428 Medfield). If you are building for a PC class system say N here.
429
430 if X86_WANT_INTEL_MID
431
432 config X86_INTEL_MID
433 bool
434
435 config X86_MDFLD
436 bool "Medfield MID platform"
437 depends on PCI
438 depends on PCI_GOANY
439 depends on X86_IO_APIC
440 select X86_INTEL_MID
441 select SFI
442 select DW_APB_TIMER
443 select APB_TIMER
444 select I2C
445 select SPI
446 select INTEL_SCU_IPC
447 select X86_PLATFORM_DEVICES
448 select MFD_INTEL_MSIC
449 ---help---
450 Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin
451 Internet Device(MID) platform.
452 Unlike standard x86 PCs, Medfield does not have many legacy devices
453 nor standard legacy replacement devices/features. e.g. Medfield does
454 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
455
456 endif
457
458 config X86_RDC321X
459 bool "RDC R-321x SoC"
460 depends on X86_32
461 depends on X86_EXTENDED_PLATFORM
462 select M486
463 select X86_REBOOTFIXUPS
464 ---help---
465 This option is needed for RDC R-321x system-on-chip, also known
466 as R-8610-(G).
467 If you don't have one of these chips, you should say N here.
468
469 config X86_32_NON_STANDARD
470 bool "Support non-standard 32-bit SMP architectures"
471 depends on X86_32 && SMP
472 depends on X86_EXTENDED_PLATFORM
473 ---help---
474 This option compiles in the NUMAQ, Summit, bigsmp, ES7000,
475 STA2X11, default subarchitectures. It is intended for a generic
476 binary kernel. If you select them all, kernel will probe it
477 one by one and will fallback to default.
478
479 # Alphabetically sorted list of Non standard 32 bit platforms
480
481 config X86_NUMAQ
482 bool "NUMAQ (IBM/Sequent)"
483 depends on X86_32_NON_STANDARD
484 depends on PCI
485 select NUMA
486 select X86_MPPARSE
487 ---help---
488 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
489 NUMA multiquad box. This changes the way that processors are
490 bootstrapped, and uses Clustered Logical APIC addressing mode instead
491 of Flat Logical. You will need a new lynxer.elf file to flash your
492 firmware with - send email to <Martin.Bligh@us.ibm.com>.
493
494 config X86_SUPPORTS_MEMORY_FAILURE
495 def_bool y
496 # MCE code calls memory_failure():
497 depends on X86_MCE
498 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
499 depends on !X86_NUMAQ
500 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
501 depends on X86_64 || !SPARSEMEM
502 select ARCH_SUPPORTS_MEMORY_FAILURE
503
504 config X86_VISWS
505 bool "SGI 320/540 (Visual Workstation)"
506 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
507 depends on X86_32_NON_STANDARD
508 ---help---
509 The SGI Visual Workstation series is an IA32-based workstation
510 based on SGI systems chips with some legacy PC hardware attached.
511
512 Say Y here to create a kernel to run on the SGI 320 or 540.
513
514 A kernel compiled for the Visual Workstation will run on general
515 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
516
517 config STA2X11
518 bool "STA2X11 Companion Chip Support"
519 depends on X86_32_NON_STANDARD && PCI
520 select X86_DEV_DMA_OPS
521 select X86_DMA_REMAP
522 select SWIOTLB
523 select MFD_STA2X11
524 select ARCH_REQUIRE_GPIOLIB
525 default n
526 ---help---
527 This adds support for boards based on the STA2X11 IO-Hub,
528 a.k.a. "ConneXt". The chip is used in place of the standard
529 PC chipset, so all "standard" peripherals are missing. If this
530 option is selected the kernel will still be able to boot on
531 standard PC machines.
532
533 config X86_SUMMIT
534 bool "Summit/EXA (IBM x440)"
535 depends on X86_32_NON_STANDARD
536 ---help---
537 This option is needed for IBM systems that use the Summit/EXA chipset.
538 In particular, it is needed for the x440.
539
540 config X86_ES7000
541 bool "Unisys ES7000 IA32 series"
542 depends on X86_32_NON_STANDARD && X86_BIGSMP
543 ---help---
544 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
545 supposed to run on an IA32-based Unisys ES7000 system.
546
547 config X86_32_IRIS
548 tristate "Eurobraille/Iris poweroff module"
549 depends on X86_32
550 ---help---
551 The Iris machines from EuroBraille do not have APM or ACPI support
552 to shut themselves down properly. A special I/O sequence is
553 needed to do so, which is what this module does at
554 kernel shutdown.
555
556 This is only for Iris machines from EuroBraille.
557
558 If unused, say N.
559
560 config SCHED_OMIT_FRAME_POINTER
561 def_bool y
562 prompt "Single-depth WCHAN output"
563 depends on X86
564 ---help---
565 Calculate simpler /proc/<PID>/wchan values. If this option
566 is disabled then wchan values will recurse back to the
567 caller function. This provides more accurate wchan values,
568 at the expense of slightly more scheduling overhead.
569
570 If in doubt, say "Y".
571
572 menuconfig PARAVIRT_GUEST
573 bool "Paravirtualized guest support"
574 ---help---
575 Say Y here to get to see options related to running Linux under
576 various hypervisors. This option alone does not add any kernel code.
577
578 If you say N, all options in this submenu will be skipped and disabled.
579
580 if PARAVIRT_GUEST
581
582 config PARAVIRT_TIME_ACCOUNTING
583 bool "Paravirtual steal time accounting"
584 select PARAVIRT
585 default n
586 ---help---
587 Select this option to enable fine granularity task steal time
588 accounting. Time spent executing other tasks in parallel with
589 the current vCPU is discounted from the vCPU power. To account for
590 that, there can be a small performance impact.
591
592 If in doubt, say N here.
593
594 source "arch/x86/xen/Kconfig"
595
596 config KVM_GUEST
597 bool "KVM Guest support (including kvmclock)"
598 select PARAVIRT
599 select PARAVIRT
600 select PARAVIRT_CLOCK
601 default y if PARAVIRT_GUEST
602 ---help---
603 This option enables various optimizations for running under the KVM
604 hypervisor. It includes a paravirtualized clock, so that instead
605 of relying on a PIT (or probably other) emulation by the
606 underlying device model, the host provides the guest with
607 timing infrastructure such as time of day, and system time
608
609 source "arch/x86/lguest/Kconfig"
610
611 config PARAVIRT
612 bool "Enable paravirtualization code"
613 ---help---
614 This changes the kernel so it can modify itself when it is run
615 under a hypervisor, potentially improving performance significantly
616 over full virtualization. However, when run without a hypervisor
617 the kernel is theoretically slower and slightly larger.
618
619 config PARAVIRT_SPINLOCKS
620 bool "Paravirtualization layer for spinlocks"
621 depends on PARAVIRT && SMP && EXPERIMENTAL
622 ---help---
623 Paravirtualized spinlocks allow a pvops backend to replace the
624 spinlock implementation with something virtualization-friendly
625 (for example, block the virtual CPU rather than spinning).
626
627 Unfortunately the downside is an up to 5% performance hit on
628 native kernels, with various workloads.
629
630 If you are unsure how to answer this question, answer N.
631
632 config PARAVIRT_CLOCK
633 bool
634
635 endif
636
637 config PARAVIRT_DEBUG
638 bool "paravirt-ops debugging"
639 depends on PARAVIRT && DEBUG_KERNEL
640 ---help---
641 Enable to debug paravirt_ops internals. Specifically, BUG if
642 a paravirt_op is missing when it is called.
643
644 config NO_BOOTMEM
645 def_bool y
646
647 config MEMTEST
648 bool "Memtest"
649 ---help---
650 This option adds a kernel parameter 'memtest', which allows memtest
651 to be set.
652 memtest=0, mean disabled; -- default
653 memtest=1, mean do 1 test pattern;
654 ...
655 memtest=4, mean do 4 test patterns.
656 If you are unsure how to answer this question, answer N.
657
658 config X86_SUMMIT_NUMA
659 def_bool y
660 depends on X86_32 && NUMA && X86_32_NON_STANDARD
661
662 config X86_CYCLONE_TIMER
663 def_bool y
664 depends on X86_SUMMIT
665
666 source "arch/x86/Kconfig.cpu"
667
668 config HPET_TIMER
669 def_bool X86_64
670 prompt "HPET Timer Support" if X86_32
671 ---help---
672 Use the IA-PC HPET (High Precision Event Timer) to manage
673 time in preference to the PIT and RTC, if a HPET is
674 present.
675 HPET is the next generation timer replacing legacy 8254s.
676 The HPET provides a stable time base on SMP
677 systems, unlike the TSC, but it is more expensive to access,
678 as it is off-chip. You can find the HPET spec at
679 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
680
681 You can safely choose Y here. However, HPET will only be
682 activated if the platform and the BIOS support this feature.
683 Otherwise the 8254 will be used for timing services.
684
685 Choose N to continue using the legacy 8254 timer.
686
687 config HPET_EMULATE_RTC
688 def_bool y
689 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
690
691 config APB_TIMER
692 def_bool y if X86_INTEL_MID
693 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
694 select DW_APB_TIMER
695 depends on X86_INTEL_MID && SFI
696 help
697 APB timer is the replacement for 8254, HPET on X86 MID platforms.
698 The APBT provides a stable time base on SMP
699 systems, unlike the TSC, but it is more expensive to access,
700 as it is off-chip. APB timers are always running regardless of CPU
701 C states, they are used as per CPU clockevent device when possible.
702
703 # Mark as expert because too many people got it wrong.
704 # The code disables itself when not needed.
705 config DMI
706 default y
707 bool "Enable DMI scanning" if EXPERT
708 ---help---
709 Enabled scanning of DMI to identify machine quirks. Say Y
710 here unless you have verified that your setup is not
711 affected by entries in the DMI blacklist. Required by PNP
712 BIOS code.
713
714 config GART_IOMMU
715 bool "GART IOMMU support" if EXPERT
716 default y
717 select SWIOTLB
718 depends on X86_64 && PCI && AMD_NB
719 ---help---
720 Support for full DMA access of devices with 32bit memory access only
721 on systems with more than 3GB. This is usually needed for USB,
722 sound, many IDE/SATA chipsets and some other devices.
723 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
724 based hardware IOMMU and a software bounce buffer based IOMMU used
725 on Intel systems and as fallback.
726 The code is only active when needed (enough memory and limited
727 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
728 too.
729
730 config CALGARY_IOMMU
731 bool "IBM Calgary IOMMU support"
732 select SWIOTLB
733 depends on X86_64 && PCI && EXPERIMENTAL
734 ---help---
735 Support for hardware IOMMUs in IBM's xSeries x366 and x460
736 systems. Needed to run systems with more than 3GB of memory
737 properly with 32-bit PCI devices that do not support DAC
738 (Double Address Cycle). Calgary also supports bus level
739 isolation, where all DMAs pass through the IOMMU. This
740 prevents them from going anywhere except their intended
741 destination. This catches hard-to-find kernel bugs and
742 mis-behaving drivers and devices that do not use the DMA-API
743 properly to set up their DMA buffers. The IOMMU can be
744 turned off at boot time with the iommu=off parameter.
745 Normally the kernel will make the right choice by itself.
746 If unsure, say Y.
747
748 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
749 def_bool y
750 prompt "Should Calgary be enabled by default?"
751 depends on CALGARY_IOMMU
752 ---help---
753 Should Calgary be enabled by default? if you choose 'y', Calgary
754 will be used (if it exists). If you choose 'n', Calgary will not be
755 used even if it exists. If you choose 'n' and would like to use
756 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
757 If unsure, say Y.
758
759 # need this always selected by IOMMU for the VIA workaround
760 config SWIOTLB
761 def_bool y if X86_64
762 ---help---
763 Support for software bounce buffers used on x86-64 systems
764 which don't have a hardware IOMMU. Using this PCI devices
765 which can only access 32-bits of memory can be used on systems
766 with more than 3 GB of memory.
767 If unsure, say Y.
768
769 config IOMMU_HELPER
770 def_bool y
771 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
772
773 config MAXSMP
774 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
775 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
776 select CPUMASK_OFFSTACK
777 ---help---
778 Enable maximum number of CPUS and NUMA Nodes for this architecture.
779 If unsure, say N.
780
781 config NR_CPUS
782 int "Maximum number of CPUs" if SMP && !MAXSMP
783 range 2 8 if SMP && X86_32 && !X86_BIGSMP
784 range 2 512 if SMP && !MAXSMP
785 default "1" if !SMP
786 default "4096" if MAXSMP
787 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
788 default "8" if SMP
789 ---help---
790 This allows you to specify the maximum number of CPUs which this
791 kernel will support. The maximum supported value is 512 and the
792 minimum value which makes sense is 2.
793
794 This is purely to save memory - each supported CPU adds
795 approximately eight kilobytes to the kernel image.
796
797 config SCHED_SMT
798 bool "SMT (Hyperthreading) scheduler support"
799 depends on X86_HT
800 ---help---
801 SMT scheduler support improves the CPU scheduler's decision making
802 when dealing with Intel Pentium 4 chips with HyperThreading at a
803 cost of slightly increased overhead in some places. If unsure say
804 N here.
805
806 config SCHED_MC
807 def_bool y
808 prompt "Multi-core scheduler support"
809 depends on X86_HT
810 ---help---
811 Multi-core scheduler support improves the CPU scheduler's decision
812 making when dealing with multi-core CPU chips at a cost of slightly
813 increased overhead in some places. If unsure say N here.
814
815 source "kernel/Kconfig.preempt"
816
817 config X86_UP_APIC
818 bool "Local APIC support on uniprocessors"
819 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
820 ---help---
821 A local APIC (Advanced Programmable Interrupt Controller) is an
822 integrated interrupt controller in the CPU. If you have a single-CPU
823 system which has a processor with a local APIC, you can say Y here to
824 enable and use it. If you say Y here even though your machine doesn't
825 have a local APIC, then the kernel will still run with no slowdown at
826 all. The local APIC supports CPU-generated self-interrupts (timer,
827 performance counters), and the NMI watchdog which detects hard
828 lockups.
829
830 config X86_UP_IOAPIC
831 bool "IO-APIC support on uniprocessors"
832 depends on X86_UP_APIC
833 ---help---
834 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
835 SMP-capable replacement for PC-style interrupt controllers. Most
836 SMP systems and many recent uniprocessor systems have one.
837
838 If you have a single-CPU system with an IO-APIC, you can say Y here
839 to use it. If you say Y here even though your machine doesn't have
840 an IO-APIC, then the kernel will still run with no slowdown at all.
841
842 config X86_LOCAL_APIC
843 def_bool y
844 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
845
846 config X86_IO_APIC
847 def_bool y
848 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC
849
850 config X86_VISWS_APIC
851 def_bool y
852 depends on X86_32 && X86_VISWS
853
854 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
855 bool "Reroute for broken boot IRQs"
856 depends on X86_IO_APIC
857 ---help---
858 This option enables a workaround that fixes a source of
859 spurious interrupts. This is recommended when threaded
860 interrupt handling is used on systems where the generation of
861 superfluous "boot interrupts" cannot be disabled.
862
863 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
864 entry in the chipset's IO-APIC is masked (as, e.g. the RT
865 kernel does during interrupt handling). On chipsets where this
866 boot IRQ generation cannot be disabled, this workaround keeps
867 the original IRQ line masked so that only the equivalent "boot
868 IRQ" is delivered to the CPUs. The workaround also tells the
869 kernel to set up the IRQ handler on the boot IRQ line. In this
870 way only one interrupt is delivered to the kernel. Otherwise
871 the spurious second interrupt may cause the kernel to bring
872 down (vital) interrupt lines.
873
874 Only affects "broken" chipsets. Interrupt sharing may be
875 increased on these systems.
876
877 config X86_MCE
878 bool "Machine Check / overheating reporting"
879 default y
880 ---help---
881 Machine Check support allows the processor to notify the
882 kernel if it detects a problem (e.g. overheating, data corruption).
883 The action the kernel takes depends on the severity of the problem,
884 ranging from warning messages to halting the machine.
885
886 config X86_MCE_INTEL
887 def_bool y
888 prompt "Intel MCE features"
889 depends on X86_MCE && X86_LOCAL_APIC
890 ---help---
891 Additional support for intel specific MCE features such as
892 the thermal monitor.
893
894 config X86_MCE_AMD
895 def_bool y
896 prompt "AMD MCE features"
897 depends on X86_MCE && X86_LOCAL_APIC
898 ---help---
899 Additional support for AMD specific MCE features such as
900 the DRAM Error Threshold.
901
902 config X86_ANCIENT_MCE
903 bool "Support for old Pentium 5 / WinChip machine checks"
904 depends on X86_32 && X86_MCE
905 ---help---
906 Include support for machine check handling on old Pentium 5 or WinChip
907 systems. These typically need to be enabled explicitely on the command
908 line.
909
910 config X86_MCE_THRESHOLD
911 depends on X86_MCE_AMD || X86_MCE_INTEL
912 def_bool y
913
914 config X86_MCE_INJECT
915 depends on X86_MCE
916 tristate "Machine check injector support"
917 ---help---
918 Provide support for injecting machine checks for testing purposes.
919 If you don't know what a machine check is and you don't do kernel
920 QA it is safe to say n.
921
922 config X86_THERMAL_VECTOR
923 def_bool y
924 depends on X86_MCE_INTEL
925
926 config VM86
927 bool "Enable VM86 support" if EXPERT
928 default y
929 depends on X86_32
930 ---help---
931 This option is required by programs like DOSEMU to run 16-bit legacy
932 code on X86 processors. It also may be needed by software like
933 XFree86 to initialize some video cards via BIOS. Disabling this
934 option saves about 6k.
935
936 config TOSHIBA
937 tristate "Toshiba Laptop support"
938 depends on X86_32
939 ---help---
940 This adds a driver to safely access the System Management Mode of
941 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
942 not work on models with a Phoenix BIOS. The System Management Mode
943 is used to set the BIOS and power saving options on Toshiba portables.
944
945 For information on utilities to make use of this driver see the
946 Toshiba Linux utilities web site at:
947 <http://www.buzzard.org.uk/toshiba/>.
948
949 Say Y if you intend to run this kernel on a Toshiba portable.
950 Say N otherwise.
951
952 config I8K
953 tristate "Dell laptop support"
954 select HWMON
955 ---help---
956 This adds a driver to safely access the System Management Mode
957 of the CPU on the Dell Inspiron 8000. The System Management Mode
958 is used to read cpu temperature and cooling fan status and to
959 control the fans on the I8K portables.
960
961 This driver has been tested only on the Inspiron 8000 but it may
962 also work with other Dell laptops. You can force loading on other
963 models by passing the parameter `force=1' to the module. Use at
964 your own risk.
965
966 For information on utilities to make use of this driver see the
967 I8K Linux utilities web site at:
968 <http://people.debian.org/~dz/i8k/>
969
970 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
971 Say N otherwise.
972
973 config X86_REBOOTFIXUPS
974 bool "Enable X86 board specific fixups for reboot"
975 depends on X86_32
976 ---help---
977 This enables chipset and/or board specific fixups to be done
978 in order to get reboot to work correctly. This is only needed on
979 some combinations of hardware and BIOS. The symptom, for which
980 this config is intended, is when reboot ends with a stalled/hung
981 system.
982
983 Currently, the only fixup is for the Geode machines using
984 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
985
986 Say Y if you want to enable the fixup. Currently, it's safe to
987 enable this option even if you don't need it.
988 Say N otherwise.
989
990 config MICROCODE
991 tristate "CPU microcode loading support"
992 select FW_LOADER
993 ---help---
994
995 If you say Y here, you will be able to update the microcode on
996 certain Intel and AMD processors. The Intel support is for the
997 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
998 Xeon etc. The AMD support is for families 0x10 and later. You will
999 obviously need the actual microcode binary data itself which is not
1000 shipped with the Linux kernel.
1001
1002 This option selects the general module only, you need to select
1003 at least one vendor specific module as well.
1004
1005 To compile this driver as a module, choose M here: the module
1006 will be called microcode.
1007
1008 config MICROCODE_INTEL
1009 bool "Intel microcode loading support"
1010 depends on MICROCODE
1011 default MICROCODE
1012 select FW_LOADER
1013 ---help---
1014 This options enables microcode patch loading support for Intel
1015 processors.
1016
1017 For latest news and information on obtaining all the required
1018 Intel ingredients for this driver, check:
1019 <http://www.urbanmyth.org/microcode/>.
1020
1021 config MICROCODE_AMD
1022 bool "AMD microcode loading support"
1023 depends on MICROCODE
1024 select FW_LOADER
1025 ---help---
1026 If you select this option, microcode patch loading support for AMD
1027 processors will be enabled.
1028
1029 config MICROCODE_OLD_INTERFACE
1030 def_bool y
1031 depends on MICROCODE
1032
1033 config X86_MSR
1034 tristate "/dev/cpu/*/msr - Model-specific register support"
1035 ---help---
1036 This device gives privileged processes access to the x86
1037 Model-Specific Registers (MSRs). It is a character device with
1038 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1039 MSR accesses are directed to a specific CPU on multi-processor
1040 systems.
1041
1042 config X86_CPUID
1043 tristate "/dev/cpu/*/cpuid - CPU information support"
1044 ---help---
1045 This device gives processes access to the x86 CPUID instruction to
1046 be executed on a specific processor. It is a character device
1047 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1048 /dev/cpu/31/cpuid.
1049
1050 choice
1051 prompt "High Memory Support"
1052 default HIGHMEM64G if X86_NUMAQ
1053 default HIGHMEM4G
1054 depends on X86_32
1055
1056 config NOHIGHMEM
1057 bool "off"
1058 depends on !X86_NUMAQ
1059 ---help---
1060 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1061 However, the address space of 32-bit x86 processors is only 4
1062 Gigabytes large. That means that, if you have a large amount of
1063 physical memory, not all of it can be "permanently mapped" by the
1064 kernel. The physical memory that's not permanently mapped is called
1065 "high memory".
1066
1067 If you are compiling a kernel which will never run on a machine with
1068 more than 1 Gigabyte total physical RAM, answer "off" here (default
1069 choice and suitable for most users). This will result in a "3GB/1GB"
1070 split: 3GB are mapped so that each process sees a 3GB virtual memory
1071 space and the remaining part of the 4GB virtual memory space is used
1072 by the kernel to permanently map as much physical memory as
1073 possible.
1074
1075 If the machine has between 1 and 4 Gigabytes physical RAM, then
1076 answer "4GB" here.
1077
1078 If more than 4 Gigabytes is used then answer "64GB" here. This
1079 selection turns Intel PAE (Physical Address Extension) mode on.
1080 PAE implements 3-level paging on IA32 processors. PAE is fully
1081 supported by Linux, PAE mode is implemented on all recent Intel
1082 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1083 then the kernel will not boot on CPUs that don't support PAE!
1084
1085 The actual amount of total physical memory will either be
1086 auto detected or can be forced by using a kernel command line option
1087 such as "mem=256M". (Try "man bootparam" or see the documentation of
1088 your boot loader (lilo or loadlin) about how to pass options to the
1089 kernel at boot time.)
1090
1091 If unsure, say "off".
1092
1093 config HIGHMEM4G
1094 bool "4GB"
1095 depends on !X86_NUMAQ
1096 ---help---
1097 Select this if you have a 32-bit processor and between 1 and 4
1098 gigabytes of physical RAM.
1099
1100 config HIGHMEM64G
1101 bool "64GB"
1102 depends on !M486
1103 select X86_PAE
1104 ---help---
1105 Select this if you have a 32-bit processor and more than 4
1106 gigabytes of physical RAM.
1107
1108 endchoice
1109
1110 choice
1111 depends on EXPERIMENTAL
1112 prompt "Memory split" if EXPERT
1113 default VMSPLIT_3G
1114 depends on X86_32
1115 ---help---
1116 Select the desired split between kernel and user memory.
1117
1118 If the address range available to the kernel is less than the
1119 physical memory installed, the remaining memory will be available
1120 as "high memory". Accessing high memory is a little more costly
1121 than low memory, as it needs to be mapped into the kernel first.
1122 Note that increasing the kernel address space limits the range
1123 available to user programs, making the address space there
1124 tighter. Selecting anything other than the default 3G/1G split
1125 will also likely make your kernel incompatible with binary-only
1126 kernel modules.
1127
1128 If you are not absolutely sure what you are doing, leave this
1129 option alone!
1130
1131 config VMSPLIT_3G
1132 bool "3G/1G user/kernel split"
1133 config VMSPLIT_3G_OPT
1134 depends on !X86_PAE
1135 bool "3G/1G user/kernel split (for full 1G low memory)"
1136 config VMSPLIT_2G
1137 bool "2G/2G user/kernel split"
1138 config VMSPLIT_2G_OPT
1139 depends on !X86_PAE
1140 bool "2G/2G user/kernel split (for full 2G low memory)"
1141 config VMSPLIT_1G
1142 bool "1G/3G user/kernel split"
1143 endchoice
1144
1145 config PAGE_OFFSET
1146 hex
1147 default 0xB0000000 if VMSPLIT_3G_OPT
1148 default 0x80000000 if VMSPLIT_2G
1149 default 0x78000000 if VMSPLIT_2G_OPT
1150 default 0x40000000 if VMSPLIT_1G
1151 default 0xC0000000
1152 depends on X86_32
1153
1154 config HIGHMEM
1155 def_bool y
1156 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1157
1158 config X86_PAE
1159 bool "PAE (Physical Address Extension) Support"
1160 depends on X86_32 && !HIGHMEM4G
1161 ---help---
1162 PAE is required for NX support, and furthermore enables
1163 larger swapspace support for non-overcommit purposes. It
1164 has the cost of more pagetable lookup overhead, and also
1165 consumes more pagetable space per process.
1166
1167 config ARCH_PHYS_ADDR_T_64BIT
1168 def_bool y
1169 depends on X86_64 || X86_PAE
1170
1171 config ARCH_DMA_ADDR_T_64BIT
1172 def_bool y
1173 depends on X86_64 || HIGHMEM64G
1174
1175 config DIRECT_GBPAGES
1176 bool "Enable 1GB pages for kernel pagetables" if EXPERT
1177 default y
1178 depends on X86_64
1179 ---help---
1180 Allow the kernel linear mapping to use 1GB pages on CPUs that
1181 support it. This can improve the kernel's performance a tiny bit by
1182 reducing TLB pressure. If in doubt, say "Y".
1183
1184 # Common NUMA Features
1185 config NUMA
1186 bool "Numa Memory Allocation and Scheduler Support"
1187 depends on SMP
1188 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1189 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1190 ---help---
1191 Enable NUMA (Non Uniform Memory Access) support.
1192
1193 The kernel will try to allocate memory used by a CPU on the
1194 local memory controller of the CPU and add some more
1195 NUMA awareness to the kernel.
1196
1197 For 64-bit this is recommended if the system is Intel Core i7
1198 (or later), AMD Opteron, or EM64T NUMA.
1199
1200 For 32-bit this is only needed on (rare) 32-bit-only platforms
1201 that support NUMA topologies, such as NUMAQ / Summit, or if you
1202 boot a 32-bit kernel on a 64-bit NUMA platform.
1203
1204 Otherwise, you should say N.
1205
1206 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1207 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1208
1209 config AMD_NUMA
1210 def_bool y
1211 prompt "Old style AMD Opteron NUMA detection"
1212 depends on X86_64 && NUMA && PCI
1213 ---help---
1214 Enable AMD NUMA node topology detection. You should say Y here if
1215 you have a multi processor AMD system. This uses an old method to
1216 read the NUMA configuration directly from the builtin Northbridge
1217 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1218 which also takes priority if both are compiled in.
1219
1220 config X86_64_ACPI_NUMA
1221 def_bool y
1222 prompt "ACPI NUMA detection"
1223 depends on X86_64 && NUMA && ACPI && PCI
1224 select ACPI_NUMA
1225 ---help---
1226 Enable ACPI SRAT based node topology detection.
1227
1228 # Some NUMA nodes have memory ranges that span
1229 # other nodes. Even though a pfn is valid and
1230 # between a node's start and end pfns, it may not
1231 # reside on that node. See memmap_init_zone()
1232 # for details.
1233 config NODES_SPAN_OTHER_NODES
1234 def_bool y
1235 depends on X86_64_ACPI_NUMA
1236
1237 config NUMA_EMU
1238 bool "NUMA emulation"
1239 depends on NUMA
1240 ---help---
1241 Enable NUMA emulation. A flat machine will be split
1242 into virtual nodes when booted with "numa=fake=N", where N is the
1243 number of nodes. This is only useful for debugging.
1244
1245 config NODES_SHIFT
1246 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1247 range 1 10
1248 default "10" if MAXSMP
1249 default "6" if X86_64
1250 default "4" if X86_NUMAQ
1251 default "3"
1252 depends on NEED_MULTIPLE_NODES
1253 ---help---
1254 Specify the maximum number of NUMA Nodes available on the target
1255 system. Increases memory reserved to accommodate various tables.
1256
1257 config HAVE_ARCH_ALLOC_REMAP
1258 def_bool y
1259 depends on X86_32 && NUMA
1260
1261 config ARCH_HAVE_MEMORY_PRESENT
1262 def_bool y
1263 depends on X86_32 && DISCONTIGMEM
1264
1265 config NEED_NODE_MEMMAP_SIZE
1266 def_bool y
1267 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1268
1269 config ARCH_FLATMEM_ENABLE
1270 def_bool y
1271 depends on X86_32 && !NUMA
1272
1273 config ARCH_DISCONTIGMEM_ENABLE
1274 def_bool y
1275 depends on NUMA && X86_32
1276
1277 config ARCH_DISCONTIGMEM_DEFAULT
1278 def_bool y
1279 depends on NUMA && X86_32
1280
1281 config ARCH_SPARSEMEM_ENABLE
1282 def_bool y
1283 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1284 select SPARSEMEM_STATIC if X86_32
1285 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1286
1287 config ARCH_SPARSEMEM_DEFAULT
1288 def_bool y
1289 depends on X86_64
1290
1291 config ARCH_SELECT_MEMORY_MODEL
1292 def_bool y
1293 depends on ARCH_SPARSEMEM_ENABLE
1294
1295 config ARCH_MEMORY_PROBE
1296 def_bool y
1297 depends on X86_64 && MEMORY_HOTPLUG
1298
1299 config ARCH_PROC_KCORE_TEXT
1300 def_bool y
1301 depends on X86_64 && PROC_KCORE
1302
1303 config ILLEGAL_POINTER_VALUE
1304 hex
1305 default 0 if X86_32
1306 default 0xdead000000000000 if X86_64
1307
1308 source "mm/Kconfig"
1309
1310 config HIGHPTE
1311 bool "Allocate 3rd-level pagetables from highmem"
1312 depends on HIGHMEM
1313 ---help---
1314 The VM uses one page table entry for each page of physical memory.
1315 For systems with a lot of RAM, this can be wasteful of precious
1316 low memory. Setting this option will put user-space page table
1317 entries in high memory.
1318
1319 config X86_CHECK_BIOS_CORRUPTION
1320 bool "Check for low memory corruption"
1321 ---help---
1322 Periodically check for memory corruption in low memory, which
1323 is suspected to be caused by BIOS. Even when enabled in the
1324 configuration, it is disabled at runtime. Enable it by
1325 setting "memory_corruption_check=1" on the kernel command
1326 line. By default it scans the low 64k of memory every 60
1327 seconds; see the memory_corruption_check_size and
1328 memory_corruption_check_period parameters in
1329 Documentation/kernel-parameters.txt to adjust this.
1330
1331 When enabled with the default parameters, this option has
1332 almost no overhead, as it reserves a relatively small amount
1333 of memory and scans it infrequently. It both detects corruption
1334 and prevents it from affecting the running system.
1335
1336 It is, however, intended as a diagnostic tool; if repeatable
1337 BIOS-originated corruption always affects the same memory,
1338 you can use memmap= to prevent the kernel from using that
1339 memory.
1340
1341 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1342 bool "Set the default setting of memory_corruption_check"
1343 depends on X86_CHECK_BIOS_CORRUPTION
1344 default y
1345 ---help---
1346 Set whether the default state of memory_corruption_check is
1347 on or off.
1348
1349 config X86_RESERVE_LOW
1350 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1351 default 64
1352 range 4 640
1353 ---help---
1354 Specify the amount of low memory to reserve for the BIOS.
1355
1356 The first page contains BIOS data structures that the kernel
1357 must not use, so that page must always be reserved.
1358
1359 By default we reserve the first 64K of physical RAM, as a
1360 number of BIOSes are known to corrupt that memory range
1361 during events such as suspend/resume or monitor cable
1362 insertion, so it must not be used by the kernel.
1363
1364 You can set this to 4 if you are absolutely sure that you
1365 trust the BIOS to get all its memory reservations and usages
1366 right. If you know your BIOS have problems beyond the
1367 default 64K area, you can set this to 640 to avoid using the
1368 entire low memory range.
1369
1370 If you have doubts about the BIOS (e.g. suspend/resume does
1371 not work or there's kernel crashes after certain hardware
1372 hotplug events) then you might want to enable
1373 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1374 typical corruption patterns.
1375
1376 Leave this to the default value of 64 if you are unsure.
1377
1378 config MATH_EMULATION
1379 bool
1380 prompt "Math emulation" if X86_32
1381 ---help---
1382 Linux can emulate a math coprocessor (used for floating point
1383 operations) if you don't have one. 486DX and Pentium processors have
1384 a math coprocessor built in, 486SX and 386 do not, unless you added
1385 a 487DX or 387, respectively. (The messages during boot time can
1386 give you some hints here ["man dmesg"].) Everyone needs either a
1387 coprocessor or this emulation.
1388
1389 If you don't have a math coprocessor, you need to say Y here; if you
1390 say Y here even though you have a coprocessor, the coprocessor will
1391 be used nevertheless. (This behavior can be changed with the kernel
1392 command line option "no387", which comes handy if your coprocessor
1393 is broken. Try "man bootparam" or see the documentation of your boot
1394 loader (lilo or loadlin) about how to pass options to the kernel at
1395 boot time.) This means that it is a good idea to say Y here if you
1396 intend to use this kernel on different machines.
1397
1398 More information about the internals of the Linux math coprocessor
1399 emulation can be found in <file:arch/x86/math-emu/README>.
1400
1401 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1402 kernel, it won't hurt.
1403
1404 config MTRR
1405 def_bool y
1406 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1407 ---help---
1408 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1409 the Memory Type Range Registers (MTRRs) may be used to control
1410 processor access to memory ranges. This is most useful if you have
1411 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1412 allows bus write transfers to be combined into a larger transfer
1413 before bursting over the PCI/AGP bus. This can increase performance
1414 of image write operations 2.5 times or more. Saying Y here creates a
1415 /proc/mtrr file which may be used to manipulate your processor's
1416 MTRRs. Typically the X server should use this.
1417
1418 This code has a reasonably generic interface so that similar
1419 control registers on other processors can be easily supported
1420 as well:
1421
1422 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1423 Registers (ARRs) which provide a similar functionality to MTRRs. For
1424 these, the ARRs are used to emulate the MTRRs.
1425 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1426 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1427 write-combining. All of these processors are supported by this code
1428 and it makes sense to say Y here if you have one of them.
1429
1430 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1431 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1432 can lead to all sorts of problems, so it's good to say Y here.
1433
1434 You can safely say Y even if your machine doesn't have MTRRs, you'll
1435 just add about 9 KB to your kernel.
1436
1437 See <file:Documentation/x86/mtrr.txt> for more information.
1438
1439 config MTRR_SANITIZER
1440 def_bool y
1441 prompt "MTRR cleanup support"
1442 depends on MTRR
1443 ---help---
1444 Convert MTRR layout from continuous to discrete, so X drivers can
1445 add writeback entries.
1446
1447 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1448 The largest mtrr entry size for a continuous block can be set with
1449 mtrr_chunk_size.
1450
1451 If unsure, say Y.
1452
1453 config MTRR_SANITIZER_ENABLE_DEFAULT
1454 int "MTRR cleanup enable value (0-1)"
1455 range 0 1
1456 default "0"
1457 depends on MTRR_SANITIZER
1458 ---help---
1459 Enable mtrr cleanup default value
1460
1461 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1462 int "MTRR cleanup spare reg num (0-7)"
1463 range 0 7
1464 default "1"
1465 depends on MTRR_SANITIZER
1466 ---help---
1467 mtrr cleanup spare entries default, it can be changed via
1468 mtrr_spare_reg_nr=N on the kernel command line.
1469
1470 config X86_PAT
1471 def_bool y
1472 prompt "x86 PAT support" if EXPERT
1473 depends on MTRR
1474 ---help---
1475 Use PAT attributes to setup page level cache control.
1476
1477 PATs are the modern equivalents of MTRRs and are much more
1478 flexible than MTRRs.
1479
1480 Say N here if you see bootup problems (boot crash, boot hang,
1481 spontaneous reboots) or a non-working video driver.
1482
1483 If unsure, say Y.
1484
1485 config ARCH_USES_PG_UNCACHED
1486 def_bool y
1487 depends on X86_PAT
1488
1489 config ARCH_RANDOM
1490 def_bool y
1491 prompt "x86 architectural random number generator" if EXPERT
1492 ---help---
1493 Enable the x86 architectural RDRAND instruction
1494 (Intel Bull Mountain technology) to generate random numbers.
1495 If supported, this is a high bandwidth, cryptographically
1496 secure hardware random number generator.
1497
1498 config X86_SMAP
1499 def_bool y
1500 prompt "Supervisor Mode Access Prevention" if EXPERT
1501 ---help---
1502 Supervisor Mode Access Prevention (SMAP) is a security
1503 feature in newer Intel processors. There is a small
1504 performance cost if this enabled and turned on; there is
1505 also a small increase in the kernel size if this is enabled.
1506
1507 If unsure, say Y.
1508
1509 config EFI
1510 bool "EFI runtime service support"
1511 depends on ACPI
1512 ---help---
1513 This enables the kernel to use EFI runtime services that are
1514 available (such as the EFI variable services).
1515
1516 This option is only useful on systems that have EFI firmware.
1517 In addition, you should use the latest ELILO loader available
1518 at <http://elilo.sourceforge.net> in order to take advantage
1519 of EFI runtime services. However, even with this option, the
1520 resultant kernel should continue to boot on existing non-EFI
1521 platforms.
1522
1523 config EFI_STUB
1524 bool "EFI stub support"
1525 depends on EFI
1526 ---help---
1527 This kernel feature allows a bzImage to be loaded directly
1528 by EFI firmware without the use of a bootloader.
1529
1530 See Documentation/x86/efi-stub.txt for more information.
1531
1532 config SECCOMP
1533 def_bool y
1534 prompt "Enable seccomp to safely compute untrusted bytecode"
1535 ---help---
1536 This kernel feature is useful for number crunching applications
1537 that may need to compute untrusted bytecode during their
1538 execution. By using pipes or other transports made available to
1539 the process as file descriptors supporting the read/write
1540 syscalls, it's possible to isolate those applications in
1541 their own address space using seccomp. Once seccomp is
1542 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1543 and the task is only allowed to execute a few safe syscalls
1544 defined by each seccomp mode.
1545
1546 If unsure, say Y. Only embedded should say N here.
1547
1548 config CC_STACKPROTECTOR
1549 bool "Enable -fstack-protector buffer overflow detection"
1550 ---help---
1551 This option turns on the -fstack-protector GCC feature. This
1552 feature puts, at the beginning of functions, a canary value on
1553 the stack just before the return address, and validates
1554 the value just before actually returning. Stack based buffer
1555 overflows (that need to overwrite this return address) now also
1556 overwrite the canary, which gets detected and the attack is then
1557 neutralized via a kernel panic.
1558
1559 This feature requires gcc version 4.2 or above, or a distribution
1560 gcc with the feature backported. Older versions are automatically
1561 detected and for those versions, this configuration option is
1562 ignored. (and a warning is printed during bootup)
1563
1564 source kernel/Kconfig.hz
1565
1566 config KEXEC
1567 bool "kexec system call"
1568 ---help---
1569 kexec is a system call that implements the ability to shutdown your
1570 current kernel, and to start another kernel. It is like a reboot
1571 but it is independent of the system firmware. And like a reboot
1572 you can start any kernel with it, not just Linux.
1573
1574 The name comes from the similarity to the exec system call.
1575
1576 It is an ongoing process to be certain the hardware in a machine
1577 is properly shutdown, so do not be surprised if this code does not
1578 initially work for you. It may help to enable device hotplugging
1579 support. As of this writing the exact hardware interface is
1580 strongly in flux, so no good recommendation can be made.
1581
1582 config CRASH_DUMP
1583 bool "kernel crash dumps"
1584 depends on X86_64 || (X86_32 && HIGHMEM)
1585 ---help---
1586 Generate crash dump after being started by kexec.
1587 This should be normally only set in special crash dump kernels
1588 which are loaded in the main kernel with kexec-tools into
1589 a specially reserved region and then later executed after
1590 a crash by kdump/kexec. The crash dump kernel must be compiled
1591 to a memory address not used by the main kernel or BIOS using
1592 PHYSICAL_START, or it must be built as a relocatable image
1593 (CONFIG_RELOCATABLE=y).
1594 For more details see Documentation/kdump/kdump.txt
1595
1596 config KEXEC_JUMP
1597 bool "kexec jump (EXPERIMENTAL)"
1598 depends on EXPERIMENTAL
1599 depends on KEXEC && HIBERNATION
1600 ---help---
1601 Jump between original kernel and kexeced kernel and invoke
1602 code in physical address mode via KEXEC
1603
1604 config PHYSICAL_START
1605 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1606 default "0x1000000"
1607 ---help---
1608 This gives the physical address where the kernel is loaded.
1609
1610 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1611 bzImage will decompress itself to above physical address and
1612 run from there. Otherwise, bzImage will run from the address where
1613 it has been loaded by the boot loader and will ignore above physical
1614 address.
1615
1616 In normal kdump cases one does not have to set/change this option
1617 as now bzImage can be compiled as a completely relocatable image
1618 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1619 address. This option is mainly useful for the folks who don't want
1620 to use a bzImage for capturing the crash dump and want to use a
1621 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1622 to be specifically compiled to run from a specific memory area
1623 (normally a reserved region) and this option comes handy.
1624
1625 So if you are using bzImage for capturing the crash dump,
1626 leave the value here unchanged to 0x1000000 and set
1627 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1628 for capturing the crash dump change this value to start of
1629 the reserved region. In other words, it can be set based on
1630 the "X" value as specified in the "crashkernel=YM@XM"
1631 command line boot parameter passed to the panic-ed
1632 kernel. Please take a look at Documentation/kdump/kdump.txt
1633 for more details about crash dumps.
1634
1635 Usage of bzImage for capturing the crash dump is recommended as
1636 one does not have to build two kernels. Same kernel can be used
1637 as production kernel and capture kernel. Above option should have
1638 gone away after relocatable bzImage support is introduced. But it
1639 is present because there are users out there who continue to use
1640 vmlinux for dump capture. This option should go away down the
1641 line.
1642
1643 Don't change this unless you know what you are doing.
1644
1645 config RELOCATABLE
1646 bool "Build a relocatable kernel"
1647 default y
1648 ---help---
1649 This builds a kernel image that retains relocation information
1650 so it can be loaded someplace besides the default 1MB.
1651 The relocations tend to make the kernel binary about 10% larger,
1652 but are discarded at runtime.
1653
1654 One use is for the kexec on panic case where the recovery kernel
1655 must live at a different physical address than the primary
1656 kernel.
1657
1658 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1659 it has been loaded at and the compile time physical address
1660 (CONFIG_PHYSICAL_START) is ignored.
1661
1662 # Relocation on x86-32 needs some additional build support
1663 config X86_NEED_RELOCS
1664 def_bool y
1665 depends on X86_32 && RELOCATABLE
1666
1667 config PHYSICAL_ALIGN
1668 hex "Alignment value to which kernel should be aligned" if X86_32
1669 default "0x1000000"
1670 range 0x2000 0x1000000
1671 ---help---
1672 This value puts the alignment restrictions on physical address
1673 where kernel is loaded and run from. Kernel is compiled for an
1674 address which meets above alignment restriction.
1675
1676 If bootloader loads the kernel at a non-aligned address and
1677 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1678 address aligned to above value and run from there.
1679
1680 If bootloader loads the kernel at a non-aligned address and
1681 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1682 load address and decompress itself to the address it has been
1683 compiled for and run from there. The address for which kernel is
1684 compiled already meets above alignment restrictions. Hence the
1685 end result is that kernel runs from a physical address meeting
1686 above alignment restrictions.
1687
1688 Don't change this unless you know what you are doing.
1689
1690 config HOTPLUG_CPU
1691 bool "Support for hot-pluggable CPUs"
1692 depends on SMP && HOTPLUG
1693 ---help---
1694 Say Y here to allow turning CPUs off and on. CPUs can be
1695 controlled through /sys/devices/system/cpu.
1696 ( Note: power management support will enable this option
1697 automatically on SMP systems. )
1698 Say N if you want to disable CPU hotplug.
1699
1700 config BOOTPARAM_HOTPLUG_CPU0
1701 bool "Set default setting of cpu0_hotpluggable"
1702 default n
1703 depends on HOTPLUG_CPU && EXPERIMENTAL
1704 ---help---
1705 Set whether default state of cpu0_hotpluggable is on or off.
1706
1707 Say Y here to enable CPU0 hotplug by default. If this switch
1708 is turned on, there is no need to give cpu0_hotplug kernel
1709 parameter and the CPU0 hotplug feature is enabled by default.
1710
1711 Please note: there are two known CPU0 dependencies if you want
1712 to enable the CPU0 hotplug feature either by this switch or by
1713 cpu0_hotplug kernel parameter.
1714
1715 First, resume from hibernate or suspend always starts from CPU0.
1716 So hibernate and suspend are prevented if CPU0 is offline.
1717
1718 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1719 offline if any interrupt can not migrate out of CPU0. There may
1720 be other CPU0 dependencies.
1721
1722 Please make sure the dependencies are under your control before
1723 you enable this feature.
1724
1725 Say N if you don't want to enable CPU0 hotplug feature by default.
1726 You still can enable the CPU0 hotplug feature at boot by kernel
1727 parameter cpu0_hotplug.
1728
1729 config DEBUG_HOTPLUG_CPU0
1730 def_bool n
1731 prompt "Debug CPU0 hotplug"
1732 depends on HOTPLUG_CPU && EXPERIMENTAL
1733 ---help---
1734 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1735 soon as possible and boots up userspace with CPU0 offlined. User
1736 can online CPU0 back after boot time.
1737
1738 To debug CPU0 hotplug, you need to enable CPU0 offline/online
1739 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
1740 compilation or giving cpu0_hotplug kernel parameter at boot.
1741
1742 If unsure, say N.
1743
1744 config COMPAT_VDSO
1745 def_bool y
1746 prompt "Compat VDSO support"
1747 depends on X86_32 || IA32_EMULATION
1748 ---help---
1749 Map the 32-bit VDSO to the predictable old-style address too.
1750
1751 Say N here if you are running a sufficiently recent glibc
1752 version (2.3.3 or later), to remove the high-mapped
1753 VDSO mapping and to exclusively use the randomized VDSO.
1754
1755 If unsure, say Y.
1756
1757 config CMDLINE_BOOL
1758 bool "Built-in kernel command line"
1759 ---help---
1760 Allow for specifying boot arguments to the kernel at
1761 build time. On some systems (e.g. embedded ones), it is
1762 necessary or convenient to provide some or all of the
1763 kernel boot arguments with the kernel itself (that is,
1764 to not rely on the boot loader to provide them.)
1765
1766 To compile command line arguments into the kernel,
1767 set this option to 'Y', then fill in the
1768 the boot arguments in CONFIG_CMDLINE.
1769
1770 Systems with fully functional boot loaders (i.e. non-embedded)
1771 should leave this option set to 'N'.
1772
1773 config CMDLINE
1774 string "Built-in kernel command string"
1775 depends on CMDLINE_BOOL
1776 default ""
1777 ---help---
1778 Enter arguments here that should be compiled into the kernel
1779 image and used at boot time. If the boot loader provides a
1780 command line at boot time, it is appended to this string to
1781 form the full kernel command line, when the system boots.
1782
1783 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1784 change this behavior.
1785
1786 In most cases, the command line (whether built-in or provided
1787 by the boot loader) should specify the device for the root
1788 file system.
1789
1790 config CMDLINE_OVERRIDE
1791 bool "Built-in command line overrides boot loader arguments"
1792 depends on CMDLINE_BOOL
1793 ---help---
1794 Set this option to 'Y' to have the kernel ignore the boot loader
1795 command line, and use ONLY the built-in command line.
1796
1797 This is used to work around broken boot loaders. This should
1798 be set to 'N' under normal conditions.
1799
1800 endmenu
1801
1802 config ARCH_ENABLE_MEMORY_HOTPLUG
1803 def_bool y
1804 depends on X86_64 || (X86_32 && HIGHMEM)
1805
1806 config ARCH_ENABLE_MEMORY_HOTREMOVE
1807 def_bool y
1808 depends on MEMORY_HOTPLUG
1809
1810 config USE_PERCPU_NUMA_NODE_ID
1811 def_bool y
1812 depends on NUMA
1813
1814 menu "Power management and ACPI options"
1815
1816 config ARCH_HIBERNATION_HEADER
1817 def_bool y
1818 depends on X86_64 && HIBERNATION
1819
1820 source "kernel/power/Kconfig"
1821
1822 source "drivers/acpi/Kconfig"
1823
1824 source "drivers/sfi/Kconfig"
1825
1826 config X86_APM_BOOT
1827 def_bool y
1828 depends on APM
1829
1830 menuconfig APM
1831 tristate "APM (Advanced Power Management) BIOS support"
1832 depends on X86_32 && PM_SLEEP
1833 ---help---
1834 APM is a BIOS specification for saving power using several different
1835 techniques. This is mostly useful for battery powered laptops with
1836 APM compliant BIOSes. If you say Y here, the system time will be
1837 reset after a RESUME operation, the /proc/apm device will provide
1838 battery status information, and user-space programs will receive
1839 notification of APM "events" (e.g. battery status change).
1840
1841 If you select "Y" here, you can disable actual use of the APM
1842 BIOS by passing the "apm=off" option to the kernel at boot time.
1843
1844 Note that the APM support is almost completely disabled for
1845 machines with more than one CPU.
1846
1847 In order to use APM, you will need supporting software. For location
1848 and more information, read <file:Documentation/power/apm-acpi.txt>
1849 and the Battery Powered Linux mini-HOWTO, available from
1850 <http://www.tldp.org/docs.html#howto>.
1851
1852 This driver does not spin down disk drives (see the hdparm(8)
1853 manpage ("man 8 hdparm") for that), and it doesn't turn off
1854 VESA-compliant "green" monitors.
1855
1856 This driver does not support the TI 4000M TravelMate and the ACER
1857 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1858 desktop machines also don't have compliant BIOSes, and this driver
1859 may cause those machines to panic during the boot phase.
1860
1861 Generally, if you don't have a battery in your machine, there isn't
1862 much point in using this driver and you should say N. If you get
1863 random kernel OOPSes or reboots that don't seem to be related to
1864 anything, try disabling/enabling this option (or disabling/enabling
1865 APM in your BIOS).
1866
1867 Some other things you should try when experiencing seemingly random,
1868 "weird" problems:
1869
1870 1) make sure that you have enough swap space and that it is
1871 enabled.
1872 2) pass the "no-hlt" option to the kernel
1873 3) switch on floating point emulation in the kernel and pass
1874 the "no387" option to the kernel
1875 4) pass the "floppy=nodma" option to the kernel
1876 5) pass the "mem=4M" option to the kernel (thereby disabling
1877 all but the first 4 MB of RAM)
1878 6) make sure that the CPU is not over clocked.
1879 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1880 8) disable the cache from your BIOS settings
1881 9) install a fan for the video card or exchange video RAM
1882 10) install a better fan for the CPU
1883 11) exchange RAM chips
1884 12) exchange the motherboard.
1885
1886 To compile this driver as a module, choose M here: the
1887 module will be called apm.
1888
1889 if APM
1890
1891 config APM_IGNORE_USER_SUSPEND
1892 bool "Ignore USER SUSPEND"
1893 ---help---
1894 This option will ignore USER SUSPEND requests. On machines with a
1895 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1896 series notebooks, it is necessary to say Y because of a BIOS bug.
1897
1898 config APM_DO_ENABLE
1899 bool "Enable PM at boot time"
1900 ---help---
1901 Enable APM features at boot time. From page 36 of the APM BIOS
1902 specification: "When disabled, the APM BIOS does not automatically
1903 power manage devices, enter the Standby State, enter the Suspend
1904 State, or take power saving steps in response to CPU Idle calls."
1905 This driver will make CPU Idle calls when Linux is idle (unless this
1906 feature is turned off -- see "Do CPU IDLE calls", below). This
1907 should always save battery power, but more complicated APM features
1908 will be dependent on your BIOS implementation. You may need to turn
1909 this option off if your computer hangs at boot time when using APM
1910 support, or if it beeps continuously instead of suspending. Turn
1911 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1912 T400CDT. This is off by default since most machines do fine without
1913 this feature.
1914
1915 config APM_CPU_IDLE
1916 bool "Make CPU Idle calls when idle"
1917 ---help---
1918 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1919 On some machines, this can activate improved power savings, such as
1920 a slowed CPU clock rate, when the machine is idle. These idle calls
1921 are made after the idle loop has run for some length of time (e.g.,
1922 333 mS). On some machines, this will cause a hang at boot time or
1923 whenever the CPU becomes idle. (On machines with more than one CPU,
1924 this option does nothing.)
1925
1926 config APM_DISPLAY_BLANK
1927 bool "Enable console blanking using APM"
1928 ---help---
1929 Enable console blanking using the APM. Some laptops can use this to
1930 turn off the LCD backlight when the screen blanker of the Linux
1931 virtual console blanks the screen. Note that this is only used by
1932 the virtual console screen blanker, and won't turn off the backlight
1933 when using the X Window system. This also doesn't have anything to
1934 do with your VESA-compliant power-saving monitor. Further, this
1935 option doesn't work for all laptops -- it might not turn off your
1936 backlight at all, or it might print a lot of errors to the console,
1937 especially if you are using gpm.
1938
1939 config APM_ALLOW_INTS
1940 bool "Allow interrupts during APM BIOS calls"
1941 ---help---
1942 Normally we disable external interrupts while we are making calls to
1943 the APM BIOS as a measure to lessen the effects of a badly behaving
1944 BIOS implementation. The BIOS should reenable interrupts if it
1945 needs to. Unfortunately, some BIOSes do not -- especially those in
1946 many of the newer IBM Thinkpads. If you experience hangs when you
1947 suspend, try setting this to Y. Otherwise, say N.
1948
1949 endif # APM
1950
1951 source "drivers/cpufreq/Kconfig"
1952
1953 source "drivers/cpuidle/Kconfig"
1954
1955 source "drivers/idle/Kconfig"
1956
1957 endmenu
1958
1959
1960 menu "Bus options (PCI etc.)"
1961
1962 config PCI
1963 bool "PCI support"
1964 default y
1965 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1966 ---help---
1967 Find out whether you have a PCI motherboard. PCI is the name of a
1968 bus system, i.e. the way the CPU talks to the other stuff inside
1969 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1970 VESA. If you have PCI, say Y, otherwise N.
1971
1972 choice
1973 prompt "PCI access mode"
1974 depends on X86_32 && PCI
1975 default PCI_GOANY
1976 ---help---
1977 On PCI systems, the BIOS can be used to detect the PCI devices and
1978 determine their configuration. However, some old PCI motherboards
1979 have BIOS bugs and may crash if this is done. Also, some embedded
1980 PCI-based systems don't have any BIOS at all. Linux can also try to
1981 detect the PCI hardware directly without using the BIOS.
1982
1983 With this option, you can specify how Linux should detect the
1984 PCI devices. If you choose "BIOS", the BIOS will be used,
1985 if you choose "Direct", the BIOS won't be used, and if you
1986 choose "MMConfig", then PCI Express MMCONFIG will be used.
1987 If you choose "Any", the kernel will try MMCONFIG, then the
1988 direct access method and falls back to the BIOS if that doesn't
1989 work. If unsure, go with the default, which is "Any".
1990
1991 config PCI_GOBIOS
1992 bool "BIOS"
1993
1994 config PCI_GOMMCONFIG
1995 bool "MMConfig"
1996
1997 config PCI_GODIRECT
1998 bool "Direct"
1999
2000 config PCI_GOOLPC
2001 bool "OLPC XO-1"
2002 depends on OLPC
2003
2004 config PCI_GOANY
2005 bool "Any"
2006
2007 endchoice
2008
2009 config PCI_BIOS
2010 def_bool y
2011 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2012
2013 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2014 config PCI_DIRECT
2015 def_bool y
2016 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2017
2018 config PCI_MMCONFIG
2019 def_bool y
2020 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2021
2022 config PCI_OLPC
2023 def_bool y
2024 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2025
2026 config PCI_XEN
2027 def_bool y
2028 depends on PCI && XEN
2029 select SWIOTLB_XEN
2030
2031 config PCI_DOMAINS
2032 def_bool y
2033 depends on PCI
2034
2035 config PCI_MMCONFIG
2036 bool "Support mmconfig PCI config space access"
2037 depends on X86_64 && PCI && ACPI
2038
2039 config PCI_CNB20LE_QUIRK
2040 bool "Read CNB20LE Host Bridge Windows" if EXPERT
2041 depends on PCI && EXPERIMENTAL
2042 help
2043 Read the PCI windows out of the CNB20LE host bridge. This allows
2044 PCI hotplug to work on systems with the CNB20LE chipset which do
2045 not have ACPI.
2046
2047 There's no public spec for this chipset, and this functionality
2048 is known to be incomplete.
2049
2050 You should say N unless you know you need this.
2051
2052 source "drivers/pci/pcie/Kconfig"
2053
2054 source "drivers/pci/Kconfig"
2055
2056 # x86_64 have no ISA slots, but can have ISA-style DMA.
2057 config ISA_DMA_API
2058 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2059 default y
2060 help
2061 Enables ISA-style DMA support for devices requiring such controllers.
2062 If unsure, say Y.
2063
2064 if X86_32
2065
2066 config ISA
2067 bool "ISA support"
2068 ---help---
2069 Find out whether you have ISA slots on your motherboard. ISA is the
2070 name of a bus system, i.e. the way the CPU talks to the other stuff
2071 inside your box. Other bus systems are PCI, EISA, MicroChannel
2072 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2073 newer boards don't support it. If you have ISA, say Y, otherwise N.
2074
2075 config EISA
2076 bool "EISA support"
2077 depends on ISA
2078 ---help---
2079 The Extended Industry Standard Architecture (EISA) bus was
2080 developed as an open alternative to the IBM MicroChannel bus.
2081
2082 The EISA bus provided some of the features of the IBM MicroChannel
2083 bus while maintaining backward compatibility with cards made for
2084 the older ISA bus. The EISA bus saw limited use between 1988 and
2085 1995 when it was made obsolete by the PCI bus.
2086
2087 Say Y here if you are building a kernel for an EISA-based machine.
2088
2089 Otherwise, say N.
2090
2091 source "drivers/eisa/Kconfig"
2092
2093 config SCx200
2094 tristate "NatSemi SCx200 support"
2095 ---help---
2096 This provides basic support for National Semiconductor's
2097 (now AMD's) Geode processors. The driver probes for the
2098 PCI-IDs of several on-chip devices, so its a good dependency
2099 for other scx200_* drivers.
2100
2101 If compiled as a module, the driver is named scx200.
2102
2103 config SCx200HR_TIMER
2104 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2105 depends on SCx200
2106 default y
2107 ---help---
2108 This driver provides a clocksource built upon the on-chip
2109 27MHz high-resolution timer. Its also a workaround for
2110 NSC Geode SC-1100's buggy TSC, which loses time when the
2111 processor goes idle (as is done by the scheduler). The
2112 other workaround is idle=poll boot option.
2113
2114 config OLPC
2115 bool "One Laptop Per Child support"
2116 depends on !X86_PAE
2117 select GPIOLIB
2118 select OF
2119 select OF_PROMTREE
2120 select IRQ_DOMAIN
2121 ---help---
2122 Add support for detecting the unique features of the OLPC
2123 XO hardware.
2124
2125 config OLPC_XO1_PM
2126 bool "OLPC XO-1 Power Management"
2127 depends on OLPC && MFD_CS5535 && PM_SLEEP
2128 select MFD_CORE
2129 ---help---
2130 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2131
2132 config OLPC_XO1_RTC
2133 bool "OLPC XO-1 Real Time Clock"
2134 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2135 ---help---
2136 Add support for the XO-1 real time clock, which can be used as a
2137 programmable wakeup source.
2138
2139 config OLPC_XO1_SCI
2140 bool "OLPC XO-1 SCI extras"
2141 depends on OLPC && OLPC_XO1_PM
2142 select POWER_SUPPLY
2143 select GPIO_CS5535
2144 select MFD_CORE
2145 ---help---
2146 Add support for SCI-based features of the OLPC XO-1 laptop:
2147 - EC-driven system wakeups
2148 - Power button
2149 - Ebook switch
2150 - Lid switch
2151 - AC adapter status updates
2152 - Battery status updates
2153
2154 config OLPC_XO15_SCI
2155 bool "OLPC XO-1.5 SCI extras"
2156 depends on OLPC && ACPI
2157 select POWER_SUPPLY
2158 ---help---
2159 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2160 - EC-driven system wakeups
2161 - AC adapter status updates
2162 - Battery status updates
2163
2164 config ALIX
2165 bool "PCEngines ALIX System Support (LED setup)"
2166 select GPIOLIB
2167 ---help---
2168 This option enables system support for the PCEngines ALIX.
2169 At present this just sets up LEDs for GPIO control on
2170 ALIX2/3/6 boards. However, other system specific setup should
2171 get added here.
2172
2173 Note: You must still enable the drivers for GPIO and LED support
2174 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2175
2176 Note: You have to set alix.force=1 for boards with Award BIOS.
2177
2178 config NET5501
2179 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2180 select GPIOLIB
2181 ---help---
2182 This option enables system support for the Soekris Engineering net5501.
2183
2184 config GEOS
2185 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2186 select GPIOLIB
2187 depends on DMI
2188 ---help---
2189 This option enables system support for the Traverse Technologies GEOS.
2190
2191 endif # X86_32
2192
2193 config AMD_NB
2194 def_bool y
2195 depends on CPU_SUP_AMD && PCI
2196
2197 source "drivers/pcmcia/Kconfig"
2198
2199 source "drivers/pci/hotplug/Kconfig"
2200
2201 config RAPIDIO
2202 bool "RapidIO support"
2203 depends on PCI
2204 default n
2205 help
2206 If you say Y here, the kernel will include drivers and
2207 infrastructure code to support RapidIO interconnect devices.
2208
2209 source "drivers/rapidio/Kconfig"
2210
2211 endmenu
2212
2213
2214 menu "Executable file formats / Emulations"
2215
2216 source "fs/Kconfig.binfmt"
2217
2218 config IA32_EMULATION
2219 bool "IA32 Emulation"
2220 depends on X86_64
2221 select COMPAT_BINFMT_ELF
2222 select HAVE_UID16
2223 ---help---
2224 Include code to run legacy 32-bit programs under a
2225 64-bit kernel. You should likely turn this on, unless you're
2226 100% sure that you don't have any 32-bit programs left.
2227
2228 config IA32_AOUT
2229 tristate "IA32 a.out support"
2230 depends on IA32_EMULATION
2231 ---help---
2232 Support old a.out binaries in the 32bit emulation.
2233
2234 config X86_X32
2235 bool "x32 ABI for 64-bit mode (EXPERIMENTAL)"
2236 depends on X86_64 && IA32_EMULATION && EXPERIMENTAL
2237 ---help---
2238 Include code to run binaries for the x32 native 32-bit ABI
2239 for 64-bit processors. An x32 process gets access to the
2240 full 64-bit register file and wide data path while leaving
2241 pointers at 32 bits for smaller memory footprint.
2242
2243 You will need a recent binutils (2.22 or later) with
2244 elf32_x86_64 support enabled to compile a kernel with this
2245 option set.
2246
2247 config COMPAT
2248 def_bool y
2249 depends on IA32_EMULATION || X86_X32
2250 select ARCH_WANT_OLD_COMPAT_IPC
2251
2252 if COMPAT
2253 config COMPAT_FOR_U64_ALIGNMENT
2254 def_bool y
2255
2256 config SYSVIPC_COMPAT
2257 def_bool y
2258 depends on SYSVIPC
2259
2260 config KEYS_COMPAT
2261 def_bool y
2262 depends on KEYS
2263 endif
2264
2265 endmenu
2266
2267
2268 config HAVE_ATOMIC_IOMAP
2269 def_bool y
2270 depends on X86_32
2271
2272 config HAVE_TEXT_POKE_SMP
2273 bool
2274 select STOP_MACHINE if SMP
2275
2276 config X86_DEV_DMA_OPS
2277 bool
2278 depends on X86_64 || STA2X11
2279
2280 config X86_DMA_REMAP
2281 bool
2282 depends on STA2X11
2283
2284 source "net/Kconfig"
2285
2286 source "drivers/Kconfig"
2287
2288 source "drivers/firmware/Kconfig"
2289
2290 source "fs/Kconfig"
2291
2292 source "arch/x86/Kconfig.debug"
2293
2294 source "security/Kconfig"
2295
2296 source "crypto/Kconfig"
2297
2298 source "arch/x86/kvm/Kconfig"
2299
2300 source "lib/Kconfig"