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1# Select 32 or 64 bit
2config 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
9config X86_32
10 def_bool !64BIT
11 select CLKSRC_I8253
12
13config X86_64
14 def_bool 64BIT
15 select X86_DEV_DMA_OPS
16
17### Arch settings
18config X86
19 def_bool y
20 select HAVE_AOUT if X86_32
21 select HAVE_UNSTABLE_SCHED_CLOCK
22 select HAVE_IDE
23 select HAVE_OPROFILE
24 select HAVE_PCSPKR_PLATFORM
25 select HAVE_PERF_EVENTS
26 select HAVE_IRQ_WORK
27 select HAVE_IOREMAP_PROT
28 select HAVE_KPROBES
29 select HAVE_MEMBLOCK
30 select HAVE_MEMBLOCK_NODE_MAP
31 select ARCH_DISCARD_MEMBLOCK
32 select ARCH_WANT_OPTIONAL_GPIOLIB
33 select ARCH_WANT_FRAME_POINTERS
34 select HAVE_DMA_ATTRS
35 select HAVE_DMA_CONTIGUOUS if !SWIOTLB
36 select HAVE_KRETPROBES
37 select HAVE_OPTPROBES
38 select HAVE_FTRACE_MCOUNT_RECORD
39 select HAVE_C_RECORDMCOUNT
40 select HAVE_DYNAMIC_FTRACE
41 select HAVE_FUNCTION_TRACER
42 select HAVE_FUNCTION_GRAPH_TRACER
43 select HAVE_FUNCTION_GRAPH_FP_TEST
44 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
45 select HAVE_SYSCALL_TRACEPOINTS
46 select HAVE_KVM
47 select HAVE_ARCH_KGDB
48 select HAVE_ARCH_TRACEHOOK
49 select HAVE_GENERIC_DMA_COHERENT if X86_32
50 select HAVE_EFFICIENT_UNALIGNED_ACCESS
51 select USER_STACKTRACE_SUPPORT
52 select HAVE_REGS_AND_STACK_ACCESS_API
53 select HAVE_DMA_API_DEBUG
54 select HAVE_KERNEL_GZIP
55 select HAVE_KERNEL_BZIP2
56 select HAVE_KERNEL_LZMA
57 select HAVE_KERNEL_XZ
58 select HAVE_KERNEL_LZO
59 select HAVE_HW_BREAKPOINT
60 select HAVE_MIXED_BREAKPOINTS_REGS
61 select PERF_EVENTS
62 select HAVE_PERF_EVENTS_NMI
63 select ANON_INODES
64 select HAVE_ALIGNED_STRUCT_PAGE if SLUB && !M386
65 select HAVE_CMPXCHG_LOCAL if !M386
66 select HAVE_CMPXCHG_DOUBLE
67 select HAVE_ARCH_KMEMCHECK
68 select HAVE_USER_RETURN_NOTIFIER
69 select ARCH_BINFMT_ELF_RANDOMIZE_PIE
70 select HAVE_ARCH_JUMP_LABEL
71 select HAVE_TEXT_POKE_SMP
72 select HAVE_GENERIC_HARDIRQS
73 select SPARSE_IRQ
74 select GENERIC_FIND_FIRST_BIT
75 select GENERIC_IRQ_PROBE
76 select GENERIC_PENDING_IRQ if SMP
77 select GENERIC_IRQ_SHOW
78 select GENERIC_CLOCKEVENTS_MIN_ADJUST
79 select IRQ_FORCED_THREADING
80 select USE_GENERIC_SMP_HELPERS if SMP
81 select HAVE_BPF_JIT if X86_64
82 select CLKEVT_I8253
83 select ARCH_HAVE_NMI_SAFE_CMPXCHG
84 select GENERIC_IOMAP
85 select DCACHE_WORD_ACCESS
86 select GENERIC_SMP_IDLE_THREAD
87 select HAVE_ARCH_SECCOMP_FILTER
88 select BUILDTIME_EXTABLE_SORT
89 select GENERIC_CMOS_UPDATE
90 select CLOCKSOURCE_WATCHDOG
91 select GENERIC_CLOCKEVENTS
92 select ARCH_CLOCKSOURCE_DATA if X86_64
93 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
94 select GENERIC_TIME_VSYSCALL if X86_64
95 select KTIME_SCALAR if X86_32
96 select GENERIC_STRNCPY_FROM_USER
97 select GENERIC_STRNLEN_USER
98
99config INSTRUCTION_DECODER
100 def_bool (KPROBES || PERF_EVENTS || UPROBES)
101
102config OUTPUT_FORMAT
103 string
104 default "elf32-i386" if X86_32
105 default "elf64-x86-64" if X86_64
106
107config ARCH_DEFCONFIG
108 string
109 default "arch/x86/configs/i386_defconfig" if X86_32
110 default "arch/x86/configs/x86_64_defconfig" if X86_64
111
112config LOCKDEP_SUPPORT
113 def_bool y
114
115config STACKTRACE_SUPPORT
116 def_bool y
117
118config HAVE_LATENCYTOP_SUPPORT
119 def_bool y
120
121config MMU
122 def_bool y
123
124config SBUS
125 bool
126
127config NEED_DMA_MAP_STATE
128 def_bool (X86_64 || INTEL_IOMMU || DMA_API_DEBUG)
129
130config NEED_SG_DMA_LENGTH
131 def_bool y
132
133config GENERIC_ISA_DMA
134 def_bool ISA_DMA_API
135
136config GENERIC_BUG
137 def_bool y
138 depends on BUG
139 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
140
141config GENERIC_BUG_RELATIVE_POINTERS
142 bool
143
144config GENERIC_HWEIGHT
145 def_bool y
146
147config GENERIC_GPIO
148 bool
149
150config ARCH_MAY_HAVE_PC_FDC
151 def_bool ISA_DMA_API
152
153config RWSEM_GENERIC_SPINLOCK
154 def_bool !X86_XADD
155
156config RWSEM_XCHGADD_ALGORITHM
157 def_bool X86_XADD
158
159config GENERIC_CALIBRATE_DELAY
160 def_bool y
161
162config ARCH_HAS_CPU_RELAX
163 def_bool y
164
165config ARCH_HAS_DEFAULT_IDLE
166 def_bool y
167
168config ARCH_HAS_CACHE_LINE_SIZE
169 def_bool y
170
171config ARCH_HAS_CPU_AUTOPROBE
172 def_bool y
173
174config HAVE_SETUP_PER_CPU_AREA
175 def_bool y
176
177config NEED_PER_CPU_EMBED_FIRST_CHUNK
178 def_bool y
179
180config NEED_PER_CPU_PAGE_FIRST_CHUNK
181 def_bool y
182
183config ARCH_HIBERNATION_POSSIBLE
184 def_bool y
185
186config ARCH_SUSPEND_POSSIBLE
187 def_bool y
188
189config ZONE_DMA32
190 bool
191 default X86_64
192
193config AUDIT_ARCH
194 bool
195 default X86_64
196
197config ARCH_SUPPORTS_OPTIMIZED_INLINING
198 def_bool y
199
200config ARCH_SUPPORTS_DEBUG_PAGEALLOC
201 def_bool y
202
203config HAVE_INTEL_TXT
204 def_bool y
205 depends on EXPERIMENTAL && INTEL_IOMMU && ACPI
206
207config X86_32_SMP
208 def_bool y
209 depends on X86_32 && SMP
210
211config X86_64_SMP
212 def_bool y
213 depends on X86_64 && SMP
214
215config X86_HT
216 def_bool y
217 depends on SMP
218
219config X86_32_LAZY_GS
220 def_bool y
221 depends on X86_32 && !CC_STACKPROTECTOR
222
223config ARCH_HWEIGHT_CFLAGS
224 string
225 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
226 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
227
228config ARCH_CPU_PROBE_RELEASE
229 def_bool y
230 depends on HOTPLUG_CPU
231
232config ARCH_SUPPORTS_UPROBES
233 def_bool y
234
235source "init/Kconfig"
236source "kernel/Kconfig.freezer"
237
238menu "Processor type and features"
239
240config ZONE_DMA
241 bool "DMA memory allocation support" if EXPERT
242 default y
243 help
244 DMA memory allocation support allows devices with less than 32-bit
245 addressing to allocate within the first 16MB of address space.
246 Disable if no such devices will be used.
247
248 If unsure, say Y.
249
250config SMP
251 bool "Symmetric multi-processing support"
252 ---help---
253 This enables support for systems with more than one CPU. If you have
254 a system with only one CPU, like most personal computers, say N. If
255 you have a system with more than one CPU, say Y.
256
257 If you say N here, the kernel will run on single and multiprocessor
258 machines, but will use only one CPU of a multiprocessor machine. If
259 you say Y here, the kernel will run on many, but not all,
260 singleprocessor machines. On a singleprocessor machine, the kernel
261 will run faster if you say N here.
262
263 Note that if you say Y here and choose architecture "586" or
264 "Pentium" under "Processor family", the kernel will not work on 486
265 architectures. Similarly, multiprocessor kernels for the "PPro"
266 architecture may not work on all Pentium based boards.
267
268 People using multiprocessor machines who say Y here should also say
269 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
270 Management" code will be disabled if you say Y here.
271
272 See also <file:Documentation/x86/i386/IO-APIC.txt>,
273 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
274 <http://www.tldp.org/docs.html#howto>.
275
276 If you don't know what to do here, say N.
277
278config X86_X2APIC
279 bool "Support x2apic"
280 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
281 ---help---
282 This enables x2apic support on CPUs that have this feature.
283
284 This allows 32-bit apic IDs (so it can support very large systems),
285 and accesses the local apic via MSRs not via mmio.
286
287 If you don't know what to do here, say N.
288
289config X86_MPPARSE
290 bool "Enable MPS table" if ACPI
291 default y
292 depends on X86_LOCAL_APIC
293 ---help---
294 For old smp systems that do not have proper acpi support. Newer systems
295 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
296
297config X86_BIGSMP
298 bool "Support for big SMP systems with more than 8 CPUs"
299 depends on X86_32 && SMP
300 ---help---
301 This option is needed for the systems that have more than 8 CPUs
302
303if X86_32
304config X86_EXTENDED_PLATFORM
305 bool "Support for extended (non-PC) x86 platforms"
306 default y
307 ---help---
308 If you disable this option then the kernel will only support
309 standard PC platforms. (which covers the vast majority of
310 systems out there.)
311
312 If you enable this option then you'll be able to select support
313 for the following (non-PC) 32 bit x86 platforms:
314 AMD Elan
315 NUMAQ (IBM/Sequent)
316 RDC R-321x SoC
317 SGI 320/540 (Visual Workstation)
318 STA2X11-based (e.g. Northville)
319 Summit/EXA (IBM x440)
320 Unisys ES7000 IA32 series
321 Moorestown MID devices
322
323 If you have one of these systems, or if you want to build a
324 generic distribution kernel, say Y here - otherwise say N.
325endif
326
327if X86_64
328config X86_EXTENDED_PLATFORM
329 bool "Support for extended (non-PC) x86 platforms"
330 default y
331 ---help---
332 If you disable this option then the kernel will only support
333 standard PC platforms. (which covers the vast majority of
334 systems out there.)
335
336 If you enable this option then you'll be able to select support
337 for the following (non-PC) 64 bit x86 platforms:
338 Numascale NumaChip
339 ScaleMP vSMP
340 SGI Ultraviolet
341
342 If you have one of these systems, or if you want to build a
343 generic distribution kernel, say Y here - otherwise say N.
344endif
345# This is an alphabetically sorted list of 64 bit extended platforms
346# Please maintain the alphabetic order if and when there are additions
347config X86_NUMACHIP
348 bool "Numascale NumaChip"
349 depends on X86_64
350 depends on X86_EXTENDED_PLATFORM
351 depends on NUMA
352 depends on SMP
353 depends on X86_X2APIC
354 ---help---
355 Adds support for Numascale NumaChip large-SMP systems. Needed to
356 enable more than ~168 cores.
357 If you don't have one of these, you should say N here.
358
359config X86_VSMP
360 bool "ScaleMP vSMP"
361 select PARAVIRT_GUEST
362 select PARAVIRT
363 depends on X86_64 && PCI
364 depends on X86_EXTENDED_PLATFORM
365 depends on SMP
366 ---help---
367 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
368 supposed to run on these EM64T-based machines. Only choose this option
369 if you have one of these machines.
370
371config X86_UV
372 bool "SGI Ultraviolet"
373 depends on X86_64
374 depends on X86_EXTENDED_PLATFORM
375 depends on NUMA
376 depends on X86_X2APIC
377 ---help---
378 This option is needed in order to support SGI Ultraviolet systems.
379 If you don't have one of these, you should say N here.
380
381# Following is an alphabetically sorted list of 32 bit extended platforms
382# Please maintain the alphabetic order if and when there are additions
383
384config X86_INTEL_CE
385 bool "CE4100 TV platform"
386 depends on PCI
387 depends on PCI_GODIRECT
388 depends on X86_32
389 depends on X86_EXTENDED_PLATFORM
390 select X86_REBOOTFIXUPS
391 select OF
392 select OF_EARLY_FLATTREE
393 select IRQ_DOMAIN
394 ---help---
395 Select for the Intel CE media processor (CE4100) SOC.
396 This option compiles in support for the CE4100 SOC for settop
397 boxes and media devices.
398
399config X86_WANT_INTEL_MID
400 bool "Intel MID platform support"
401 depends on X86_32
402 depends on X86_EXTENDED_PLATFORM
403 ---help---
404 Select to build a kernel capable of supporting Intel MID platform
405 systems which do not have the PCI legacy interfaces (Moorestown,
406 Medfield). If you are building for a PC class system say N here.
407
408if X86_WANT_INTEL_MID
409
410config X86_INTEL_MID
411 bool
412
413config X86_MDFLD
414 bool "Medfield MID platform"
415 depends on PCI
416 depends on PCI_GOANY
417 depends on X86_IO_APIC
418 select X86_INTEL_MID
419 select SFI
420 select DW_APB_TIMER
421 select APB_TIMER
422 select I2C
423 select SPI
424 select INTEL_SCU_IPC
425 select X86_PLATFORM_DEVICES
426 select MFD_INTEL_MSIC
427 ---help---
428 Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin
429 Internet Device(MID) platform.
430 Unlike standard x86 PCs, Medfield does not have many legacy devices
431 nor standard legacy replacement devices/features. e.g. Medfield does
432 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
433
434endif
435
436config X86_RDC321X
437 bool "RDC R-321x SoC"
438 depends on X86_32
439 depends on X86_EXTENDED_PLATFORM
440 select M486
441 select X86_REBOOTFIXUPS
442 ---help---
443 This option is needed for RDC R-321x system-on-chip, also known
444 as R-8610-(G).
445 If you don't have one of these chips, you should say N here.
446
447config X86_32_NON_STANDARD
448 bool "Support non-standard 32-bit SMP architectures"
449 depends on X86_32 && SMP
450 depends on X86_EXTENDED_PLATFORM
451 ---help---
452 This option compiles in the NUMAQ, Summit, bigsmp, ES7000,
453 STA2X11, default subarchitectures. It is intended for a generic
454 binary kernel. If you select them all, kernel will probe it
455 one by one and will fallback to default.
456
457# Alphabetically sorted list of Non standard 32 bit platforms
458
459config X86_NUMAQ
460 bool "NUMAQ (IBM/Sequent)"
461 depends on X86_32_NON_STANDARD
462 depends on PCI
463 select NUMA
464 select X86_MPPARSE
465 ---help---
466 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
467 NUMA multiquad box. This changes the way that processors are
468 bootstrapped, and uses Clustered Logical APIC addressing mode instead
469 of Flat Logical. You will need a new lynxer.elf file to flash your
470 firmware with - send email to <Martin.Bligh@us.ibm.com>.
471
472config X86_SUPPORTS_MEMORY_FAILURE
473 def_bool y
474 # MCE code calls memory_failure():
475 depends on X86_MCE
476 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
477 depends on !X86_NUMAQ
478 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
479 depends on X86_64 || !SPARSEMEM
480 select ARCH_SUPPORTS_MEMORY_FAILURE
481
482config X86_VISWS
483 bool "SGI 320/540 (Visual Workstation)"
484 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
485 depends on X86_32_NON_STANDARD
486 ---help---
487 The SGI Visual Workstation series is an IA32-based workstation
488 based on SGI systems chips with some legacy PC hardware attached.
489
490 Say Y here to create a kernel to run on the SGI 320 or 540.
491
492 A kernel compiled for the Visual Workstation will run on general
493 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
494
495config STA2X11
496 bool "STA2X11 Companion Chip Support"
497 depends on X86_32_NON_STANDARD && PCI
498 select X86_DEV_DMA_OPS
499 select X86_DMA_REMAP
500 select SWIOTLB
501 select MFD_STA2X11
502 select ARCH_REQUIRE_GPIOLIB
503 default n
504 ---help---
505 This adds support for boards based on the STA2X11 IO-Hub,
506 a.k.a. "ConneXt". The chip is used in place of the standard
507 PC chipset, so all "standard" peripherals are missing. If this
508 option is selected the kernel will still be able to boot on
509 standard PC machines.
510
511config X86_SUMMIT
512 bool "Summit/EXA (IBM x440)"
513 depends on X86_32_NON_STANDARD
514 ---help---
515 This option is needed for IBM systems that use the Summit/EXA chipset.
516 In particular, it is needed for the x440.
517
518config X86_ES7000
519 bool "Unisys ES7000 IA32 series"
520 depends on X86_32_NON_STANDARD && X86_BIGSMP
521 ---help---
522 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
523 supposed to run on an IA32-based Unisys ES7000 system.
524
525config X86_32_IRIS
526 tristate "Eurobraille/Iris poweroff module"
527 depends on X86_32
528 ---help---
529 The Iris machines from EuroBraille do not have APM or ACPI support
530 to shut themselves down properly. A special I/O sequence is
531 needed to do so, which is what this module does at
532 kernel shutdown.
533
534 This is only for Iris machines from EuroBraille.
535
536 If unused, say N.
537
538config SCHED_OMIT_FRAME_POINTER
539 def_bool y
540 prompt "Single-depth WCHAN output"
541 depends on X86
542 ---help---
543 Calculate simpler /proc/<PID>/wchan values. If this option
544 is disabled then wchan values will recurse back to the
545 caller function. This provides more accurate wchan values,
546 at the expense of slightly more scheduling overhead.
547
548 If in doubt, say "Y".
549
550menuconfig PARAVIRT_GUEST
551 bool "Paravirtualized guest support"
552 ---help---
553 Say Y here to get to see options related to running Linux under
554 various hypervisors. This option alone does not add any kernel code.
555
556 If you say N, all options in this submenu will be skipped and disabled.
557
558if PARAVIRT_GUEST
559
560config PARAVIRT_TIME_ACCOUNTING
561 bool "Paravirtual steal time accounting"
562 select PARAVIRT
563 default n
564 ---help---
565 Select this option to enable fine granularity task steal time
566 accounting. Time spent executing other tasks in parallel with
567 the current vCPU is discounted from the vCPU power. To account for
568 that, there can be a small performance impact.
569
570 If in doubt, say N here.
571
572source "arch/x86/xen/Kconfig"
573
574config KVM_CLOCK
575 bool "KVM paravirtualized clock"
576 select PARAVIRT
577 select PARAVIRT_CLOCK
578 ---help---
579 Turning on this option will allow you to run a paravirtualized clock
580 when running over the KVM hypervisor. Instead of relying on a PIT
581 (or probably other) emulation by the underlying device model, the host
582 provides the guest with timing infrastructure such as time of day, and
583 system time
584
585config KVM_GUEST
586 bool "KVM Guest support"
587 select PARAVIRT
588 ---help---
589 This option enables various optimizations for running under the KVM
590 hypervisor.
591
592source "arch/x86/lguest/Kconfig"
593
594config PARAVIRT
595 bool "Enable paravirtualization code"
596 ---help---
597 This changes the kernel so it can modify itself when it is run
598 under a hypervisor, potentially improving performance significantly
599 over full virtualization. However, when run without a hypervisor
600 the kernel is theoretically slower and slightly larger.
601
602config PARAVIRT_SPINLOCKS
603 bool "Paravirtualization layer for spinlocks"
604 depends on PARAVIRT && SMP && EXPERIMENTAL
605 ---help---
606 Paravirtualized spinlocks allow a pvops backend to replace the
607 spinlock implementation with something virtualization-friendly
608 (for example, block the virtual CPU rather than spinning).
609
610 Unfortunately the downside is an up to 5% performance hit on
611 native kernels, with various workloads.
612
613 If you are unsure how to answer this question, answer N.
614
615config PARAVIRT_CLOCK
616 bool
617
618endif
619
620config PARAVIRT_DEBUG
621 bool "paravirt-ops debugging"
622 depends on PARAVIRT && DEBUG_KERNEL
623 ---help---
624 Enable to debug paravirt_ops internals. Specifically, BUG if
625 a paravirt_op is missing when it is called.
626
627config NO_BOOTMEM
628 def_bool y
629
630config MEMTEST
631 bool "Memtest"
632 ---help---
633 This option adds a kernel parameter 'memtest', which allows memtest
634 to be set.
635 memtest=0, mean disabled; -- default
636 memtest=1, mean do 1 test pattern;
637 ...
638 memtest=4, mean do 4 test patterns.
639 If you are unsure how to answer this question, answer N.
640
641config X86_SUMMIT_NUMA
642 def_bool y
643 depends on X86_32 && NUMA && X86_32_NON_STANDARD
644
645config X86_CYCLONE_TIMER
646 def_bool y
647 depends on X86_SUMMIT
648
649source "arch/x86/Kconfig.cpu"
650
651config HPET_TIMER
652 def_bool X86_64
653 prompt "HPET Timer Support" if X86_32
654 ---help---
655 Use the IA-PC HPET (High Precision Event Timer) to manage
656 time in preference to the PIT and RTC, if a HPET is
657 present.
658 HPET is the next generation timer replacing legacy 8254s.
659 The HPET provides a stable time base on SMP
660 systems, unlike the TSC, but it is more expensive to access,
661 as it is off-chip. You can find the HPET spec at
662 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
663
664 You can safely choose Y here. However, HPET will only be
665 activated if the platform and the BIOS support this feature.
666 Otherwise the 8254 will be used for timing services.
667
668 Choose N to continue using the legacy 8254 timer.
669
670config HPET_EMULATE_RTC
671 def_bool y
672 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
673
674config APB_TIMER
675 def_bool y if X86_INTEL_MID
676 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
677 select DW_APB_TIMER
678 depends on X86_INTEL_MID && SFI
679 help
680 APB timer is the replacement for 8254, HPET on X86 MID platforms.
681 The APBT provides a stable time base on SMP
682 systems, unlike the TSC, but it is more expensive to access,
683 as it is off-chip. APB timers are always running regardless of CPU
684 C states, they are used as per CPU clockevent device when possible.
685
686# Mark as expert because too many people got it wrong.
687# The code disables itself when not needed.
688config DMI
689 default y
690 bool "Enable DMI scanning" if EXPERT
691 ---help---
692 Enabled scanning of DMI to identify machine quirks. Say Y
693 here unless you have verified that your setup is not
694 affected by entries in the DMI blacklist. Required by PNP
695 BIOS code.
696
697config GART_IOMMU
698 bool "GART IOMMU support" if EXPERT
699 default y
700 select SWIOTLB
701 depends on X86_64 && PCI && AMD_NB
702 ---help---
703 Support for full DMA access of devices with 32bit memory access only
704 on systems with more than 3GB. This is usually needed for USB,
705 sound, many IDE/SATA chipsets and some other devices.
706 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
707 based hardware IOMMU and a software bounce buffer based IOMMU used
708 on Intel systems and as fallback.
709 The code is only active when needed (enough memory and limited
710 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
711 too.
712
713config CALGARY_IOMMU
714 bool "IBM Calgary IOMMU support"
715 select SWIOTLB
716 depends on X86_64 && PCI && EXPERIMENTAL
717 ---help---
718 Support for hardware IOMMUs in IBM's xSeries x366 and x460
719 systems. Needed to run systems with more than 3GB of memory
720 properly with 32-bit PCI devices that do not support DAC
721 (Double Address Cycle). Calgary also supports bus level
722 isolation, where all DMAs pass through the IOMMU. This
723 prevents them from going anywhere except their intended
724 destination. This catches hard-to-find kernel bugs and
725 mis-behaving drivers and devices that do not use the DMA-API
726 properly to set up their DMA buffers. The IOMMU can be
727 turned off at boot time with the iommu=off parameter.
728 Normally the kernel will make the right choice by itself.
729 If unsure, say Y.
730
731config CALGARY_IOMMU_ENABLED_BY_DEFAULT
732 def_bool y
733 prompt "Should Calgary be enabled by default?"
734 depends on CALGARY_IOMMU
735 ---help---
736 Should Calgary be enabled by default? if you choose 'y', Calgary
737 will be used (if it exists). If you choose 'n', Calgary will not be
738 used even if it exists. If you choose 'n' and would like to use
739 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
740 If unsure, say Y.
741
742# need this always selected by IOMMU for the VIA workaround
743config SWIOTLB
744 def_bool y if X86_64
745 ---help---
746 Support for software bounce buffers used on x86-64 systems
747 which don't have a hardware IOMMU (e.g. the current generation
748 of Intel's x86-64 CPUs). Using this PCI devices which can only
749 access 32-bits of memory can be used on systems with more than
750 3 GB of memory. If unsure, say Y.
751
752config IOMMU_HELPER
753 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
754
755config MAXSMP
756 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
757 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
758 select CPUMASK_OFFSTACK
759 ---help---
760 Enable maximum number of CPUS and NUMA Nodes for this architecture.
761 If unsure, say N.
762
763config NR_CPUS
764 int "Maximum number of CPUs" if SMP && !MAXSMP
765 range 2 8 if SMP && X86_32 && !X86_BIGSMP
766 range 2 512 if SMP && !MAXSMP
767 default "1" if !SMP
768 default "4096" if MAXSMP
769 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
770 default "8" if SMP
771 ---help---
772 This allows you to specify the maximum number of CPUs which this
773 kernel will support. The maximum supported value is 512 and the
774 minimum value which makes sense is 2.
775
776 This is purely to save memory - each supported CPU adds
777 approximately eight kilobytes to the kernel image.
778
779config SCHED_SMT
780 bool "SMT (Hyperthreading) scheduler support"
781 depends on X86_HT
782 ---help---
783 SMT scheduler support improves the CPU scheduler's decision making
784 when dealing with Intel Pentium 4 chips with HyperThreading at a
785 cost of slightly increased overhead in some places. If unsure say
786 N here.
787
788config SCHED_MC
789 def_bool y
790 prompt "Multi-core scheduler support"
791 depends on X86_HT
792 ---help---
793 Multi-core scheduler support improves the CPU scheduler's decision
794 making when dealing with multi-core CPU chips at a cost of slightly
795 increased overhead in some places. If unsure say N here.
796
797config IRQ_TIME_ACCOUNTING
798 bool "Fine granularity task level IRQ time accounting"
799 default n
800 ---help---
801 Select this option to enable fine granularity task irq time
802 accounting. This is done by reading a timestamp on each
803 transitions between softirq and hardirq state, so there can be a
804 small performance impact.
805
806 If in doubt, say N here.
807
808source "kernel/Kconfig.preempt"
809
810config X86_UP_APIC
811 bool "Local APIC support on uniprocessors"
812 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
813 ---help---
814 A local APIC (Advanced Programmable Interrupt Controller) is an
815 integrated interrupt controller in the CPU. If you have a single-CPU
816 system which has a processor with a local APIC, you can say Y here to
817 enable and use it. If you say Y here even though your machine doesn't
818 have a local APIC, then the kernel will still run with no slowdown at
819 all. The local APIC supports CPU-generated self-interrupts (timer,
820 performance counters), and the NMI watchdog which detects hard
821 lockups.
822
823config X86_UP_IOAPIC
824 bool "IO-APIC support on uniprocessors"
825 depends on X86_UP_APIC
826 ---help---
827 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
828 SMP-capable replacement for PC-style interrupt controllers. Most
829 SMP systems and many recent uniprocessor systems have one.
830
831 If you have a single-CPU system with an IO-APIC, you can say Y here
832 to use it. If you say Y here even though your machine doesn't have
833 an IO-APIC, then the kernel will still run with no slowdown at all.
834
835config X86_LOCAL_APIC
836 def_bool y
837 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
838
839config X86_IO_APIC
840 def_bool y
841 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC
842
843config X86_VISWS_APIC
844 def_bool y
845 depends on X86_32 && X86_VISWS
846
847config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
848 bool "Reroute for broken boot IRQs"
849 depends on X86_IO_APIC
850 ---help---
851 This option enables a workaround that fixes a source of
852 spurious interrupts. This is recommended when threaded
853 interrupt handling is used on systems where the generation of
854 superfluous "boot interrupts" cannot be disabled.
855
856 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
857 entry in the chipset's IO-APIC is masked (as, e.g. the RT
858 kernel does during interrupt handling). On chipsets where this
859 boot IRQ generation cannot be disabled, this workaround keeps
860 the original IRQ line masked so that only the equivalent "boot
861 IRQ" is delivered to the CPUs. The workaround also tells the
862 kernel to set up the IRQ handler on the boot IRQ line. In this
863 way only one interrupt is delivered to the kernel. Otherwise
864 the spurious second interrupt may cause the kernel to bring
865 down (vital) interrupt lines.
866
867 Only affects "broken" chipsets. Interrupt sharing may be
868 increased on these systems.
869
870config X86_MCE
871 bool "Machine Check / overheating reporting"
872 ---help---
873 Machine Check support allows the processor to notify the
874 kernel if it detects a problem (e.g. overheating, data corruption).
875 The action the kernel takes depends on the severity of the problem,
876 ranging from warning messages to halting the machine.
877
878config X86_MCE_INTEL
879 def_bool y
880 prompt "Intel MCE features"
881 depends on X86_MCE && X86_LOCAL_APIC
882 ---help---
883 Additional support for intel specific MCE features such as
884 the thermal monitor.
885
886config X86_MCE_AMD
887 def_bool y
888 prompt "AMD MCE features"
889 depends on X86_MCE && X86_LOCAL_APIC
890 ---help---
891 Additional support for AMD specific MCE features such as
892 the DRAM Error Threshold.
893
894config X86_ANCIENT_MCE
895 bool "Support for old Pentium 5 / WinChip machine checks"
896 depends on X86_32 && X86_MCE
897 ---help---
898 Include support for machine check handling on old Pentium 5 or WinChip
899 systems. These typically need to be enabled explicitely on the command
900 line.
901
902config X86_MCE_THRESHOLD
903 depends on X86_MCE_AMD || X86_MCE_INTEL
904 def_bool y
905
906config X86_MCE_INJECT
907 depends on X86_MCE
908 tristate "Machine check injector support"
909 ---help---
910 Provide support for injecting machine checks for testing purposes.
911 If you don't know what a machine check is and you don't do kernel
912 QA it is safe to say n.
913
914config X86_THERMAL_VECTOR
915 def_bool y
916 depends on X86_MCE_INTEL
917
918config VM86
919 bool "Enable VM86 support" if EXPERT
920 default y
921 depends on X86_32
922 ---help---
923 This option is required by programs like DOSEMU to run 16-bit legacy
924 code on X86 processors. It also may be needed by software like
925 XFree86 to initialize some video cards via BIOS. Disabling this
926 option saves about 6k.
927
928config TOSHIBA
929 tristate "Toshiba Laptop support"
930 depends on X86_32
931 ---help---
932 This adds a driver to safely access the System Management Mode of
933 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
934 not work on models with a Phoenix BIOS. The System Management Mode
935 is used to set the BIOS and power saving options on Toshiba portables.
936
937 For information on utilities to make use of this driver see the
938 Toshiba Linux utilities web site at:
939 <http://www.buzzard.org.uk/toshiba/>.
940
941 Say Y if you intend to run this kernel on a Toshiba portable.
942 Say N otherwise.
943
944config I8K
945 tristate "Dell laptop support"
946 select HWMON
947 ---help---
948 This adds a driver to safely access the System Management Mode
949 of the CPU on the Dell Inspiron 8000. The System Management Mode
950 is used to read cpu temperature and cooling fan status and to
951 control the fans on the I8K portables.
952
953 This driver has been tested only on the Inspiron 8000 but it may
954 also work with other Dell laptops. You can force loading on other
955 models by passing the parameter `force=1' to the module. Use at
956 your own risk.
957
958 For information on utilities to make use of this driver see the
959 I8K Linux utilities web site at:
960 <http://people.debian.org/~dz/i8k/>
961
962 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
963 Say N otherwise.
964
965config X86_REBOOTFIXUPS
966 bool "Enable X86 board specific fixups for reboot"
967 depends on X86_32
968 ---help---
969 This enables chipset and/or board specific fixups to be done
970 in order to get reboot to work correctly. This is only needed on
971 some combinations of hardware and BIOS. The symptom, for which
972 this config is intended, is when reboot ends with a stalled/hung
973 system.
974
975 Currently, the only fixup is for the Geode machines using
976 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
977
978 Say Y if you want to enable the fixup. Currently, it's safe to
979 enable this option even if you don't need it.
980 Say N otherwise.
981
982config MICROCODE
983 tristate "/dev/cpu/microcode - microcode support"
984 select FW_LOADER
985 ---help---
986 If you say Y here, you will be able to update the microcode on
987 certain Intel and AMD processors. The Intel support is for the
988 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
989 Pentium 4, Xeon etc. The AMD support is for family 0x10 and
990 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
991 You will obviously need the actual microcode binary data itself
992 which is not shipped with the Linux kernel.
993
994 This option selects the general module only, you need to select
995 at least one vendor specific module as well.
996
997 To compile this driver as a module, choose M here: the
998 module will be called microcode.
999
1000config MICROCODE_INTEL
1001 bool "Intel microcode patch loading support"
1002 depends on MICROCODE
1003 default MICROCODE
1004 select FW_LOADER
1005 ---help---
1006 This options enables microcode patch loading support for Intel
1007 processors.
1008
1009 For latest news and information on obtaining all the required
1010 Intel ingredients for this driver, check:
1011 <http://www.urbanmyth.org/microcode/>.
1012
1013config MICROCODE_AMD
1014 bool "AMD microcode patch loading support"
1015 depends on MICROCODE
1016 select FW_LOADER
1017 ---help---
1018 If you select this option, microcode patch loading support for AMD
1019 processors will be enabled.
1020
1021config MICROCODE_OLD_INTERFACE
1022 def_bool y
1023 depends on MICROCODE
1024
1025config X86_MSR
1026 tristate "/dev/cpu/*/msr - Model-specific register support"
1027 ---help---
1028 This device gives privileged processes access to the x86
1029 Model-Specific Registers (MSRs). It is a character device with
1030 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1031 MSR accesses are directed to a specific CPU on multi-processor
1032 systems.
1033
1034config X86_CPUID
1035 tristate "/dev/cpu/*/cpuid - CPU information support"
1036 ---help---
1037 This device gives processes access to the x86 CPUID instruction to
1038 be executed on a specific processor. It is a character device
1039 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1040 /dev/cpu/31/cpuid.
1041
1042choice
1043 prompt "High Memory Support"
1044 default HIGHMEM64G if X86_NUMAQ
1045 default HIGHMEM4G
1046 depends on X86_32
1047
1048config NOHIGHMEM
1049 bool "off"
1050 depends on !X86_NUMAQ
1051 ---help---
1052 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1053 However, the address space of 32-bit x86 processors is only 4
1054 Gigabytes large. That means that, if you have a large amount of
1055 physical memory, not all of it can be "permanently mapped" by the
1056 kernel. The physical memory that's not permanently mapped is called
1057 "high memory".
1058
1059 If you are compiling a kernel which will never run on a machine with
1060 more than 1 Gigabyte total physical RAM, answer "off" here (default
1061 choice and suitable for most users). This will result in a "3GB/1GB"
1062 split: 3GB are mapped so that each process sees a 3GB virtual memory
1063 space and the remaining part of the 4GB virtual memory space is used
1064 by the kernel to permanently map as much physical memory as
1065 possible.
1066
1067 If the machine has between 1 and 4 Gigabytes physical RAM, then
1068 answer "4GB" here.
1069
1070 If more than 4 Gigabytes is used then answer "64GB" here. This
1071 selection turns Intel PAE (Physical Address Extension) mode on.
1072 PAE implements 3-level paging on IA32 processors. PAE is fully
1073 supported by Linux, PAE mode is implemented on all recent Intel
1074 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1075 then the kernel will not boot on CPUs that don't support PAE!
1076
1077 The actual amount of total physical memory will either be
1078 auto detected or can be forced by using a kernel command line option
1079 such as "mem=256M". (Try "man bootparam" or see the documentation of
1080 your boot loader (lilo or loadlin) about how to pass options to the
1081 kernel at boot time.)
1082
1083 If unsure, say "off".
1084
1085config HIGHMEM4G
1086 bool "4GB"
1087 depends on !X86_NUMAQ
1088 ---help---
1089 Select this if you have a 32-bit processor and between 1 and 4
1090 gigabytes of physical RAM.
1091
1092config HIGHMEM64G
1093 bool "64GB"
1094 depends on !M386 && !M486
1095 select X86_PAE
1096 ---help---
1097 Select this if you have a 32-bit processor and more than 4
1098 gigabytes of physical RAM.
1099
1100endchoice
1101
1102choice
1103 depends on EXPERIMENTAL
1104 prompt "Memory split" if EXPERT
1105 default VMSPLIT_3G
1106 depends on X86_32
1107 ---help---
1108 Select the desired split between kernel and user memory.
1109
1110 If the address range available to the kernel is less than the
1111 physical memory installed, the remaining memory will be available
1112 as "high memory". Accessing high memory is a little more costly
1113 than low memory, as it needs to be mapped into the kernel first.
1114 Note that increasing the kernel address space limits the range
1115 available to user programs, making the address space there
1116 tighter. Selecting anything other than the default 3G/1G split
1117 will also likely make your kernel incompatible with binary-only
1118 kernel modules.
1119
1120 If you are not absolutely sure what you are doing, leave this
1121 option alone!
1122
1123 config VMSPLIT_3G
1124 bool "3G/1G user/kernel split"
1125 config VMSPLIT_3G_OPT
1126 depends on !X86_PAE
1127 bool "3G/1G user/kernel split (for full 1G low memory)"
1128 config VMSPLIT_2G
1129 bool "2G/2G user/kernel split"
1130 config VMSPLIT_2G_OPT
1131 depends on !X86_PAE
1132 bool "2G/2G user/kernel split (for full 2G low memory)"
1133 config VMSPLIT_1G
1134 bool "1G/3G user/kernel split"
1135endchoice
1136
1137config PAGE_OFFSET
1138 hex
1139 default 0xB0000000 if VMSPLIT_3G_OPT
1140 default 0x80000000 if VMSPLIT_2G
1141 default 0x78000000 if VMSPLIT_2G_OPT
1142 default 0x40000000 if VMSPLIT_1G
1143 default 0xC0000000
1144 depends on X86_32
1145
1146config HIGHMEM
1147 def_bool y
1148 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1149
1150config X86_PAE
1151 bool "PAE (Physical Address Extension) Support"
1152 depends on X86_32 && !HIGHMEM4G
1153 ---help---
1154 PAE is required for NX support, and furthermore enables
1155 larger swapspace support for non-overcommit purposes. It
1156 has the cost of more pagetable lookup overhead, and also
1157 consumes more pagetable space per process.
1158
1159config ARCH_PHYS_ADDR_T_64BIT
1160 def_bool X86_64 || X86_PAE
1161
1162config ARCH_DMA_ADDR_T_64BIT
1163 def_bool X86_64 || HIGHMEM64G
1164
1165config DIRECT_GBPAGES
1166 bool "Enable 1GB pages for kernel pagetables" if EXPERT
1167 default y
1168 depends on X86_64
1169 ---help---
1170 Allow the kernel linear mapping to use 1GB pages on CPUs that
1171 support it. This can improve the kernel's performance a tiny bit by
1172 reducing TLB pressure. If in doubt, say "Y".
1173
1174# Common NUMA Features
1175config NUMA
1176 bool "Numa Memory Allocation and Scheduler Support"
1177 depends on SMP
1178 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1179 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1180 ---help---
1181 Enable NUMA (Non Uniform Memory Access) support.
1182
1183 The kernel will try to allocate memory used by a CPU on the
1184 local memory controller of the CPU and add some more
1185 NUMA awareness to the kernel.
1186
1187 For 64-bit this is recommended if the system is Intel Core i7
1188 (or later), AMD Opteron, or EM64T NUMA.
1189
1190 For 32-bit this is only needed on (rare) 32-bit-only platforms
1191 that support NUMA topologies, such as NUMAQ / Summit, or if you
1192 boot a 32-bit kernel on a 64-bit NUMA platform.
1193
1194 Otherwise, you should say N.
1195
1196comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1197 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1198
1199config AMD_NUMA
1200 def_bool y
1201 prompt "Old style AMD Opteron NUMA detection"
1202 depends on X86_64 && NUMA && PCI
1203 ---help---
1204 Enable AMD NUMA node topology detection. You should say Y here if
1205 you have a multi processor AMD system. This uses an old method to
1206 read the NUMA configuration directly from the builtin Northbridge
1207 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1208 which also takes priority if both are compiled in.
1209
1210config X86_64_ACPI_NUMA
1211 def_bool y
1212 prompt "ACPI NUMA detection"
1213 depends on X86_64 && NUMA && ACPI && PCI
1214 select ACPI_NUMA
1215 ---help---
1216 Enable ACPI SRAT based node topology detection.
1217
1218# Some NUMA nodes have memory ranges that span
1219# other nodes. Even though a pfn is valid and
1220# between a node's start and end pfns, it may not
1221# reside on that node. See memmap_init_zone()
1222# for details.
1223config NODES_SPAN_OTHER_NODES
1224 def_bool y
1225 depends on X86_64_ACPI_NUMA
1226
1227config NUMA_EMU
1228 bool "NUMA emulation"
1229 depends on NUMA
1230 ---help---
1231 Enable NUMA emulation. A flat machine will be split
1232 into virtual nodes when booted with "numa=fake=N", where N is the
1233 number of nodes. This is only useful for debugging.
1234
1235config NODES_SHIFT
1236 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1237 range 1 10
1238 default "10" if MAXSMP
1239 default "6" if X86_64
1240 default "4" if X86_NUMAQ
1241 default "3"
1242 depends on NEED_MULTIPLE_NODES
1243 ---help---
1244 Specify the maximum number of NUMA Nodes available on the target
1245 system. Increases memory reserved to accommodate various tables.
1246
1247config HAVE_ARCH_ALLOC_REMAP
1248 def_bool y
1249 depends on X86_32 && NUMA
1250
1251config ARCH_HAVE_MEMORY_PRESENT
1252 def_bool y
1253 depends on X86_32 && DISCONTIGMEM
1254
1255config NEED_NODE_MEMMAP_SIZE
1256 def_bool y
1257 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1258
1259config ARCH_FLATMEM_ENABLE
1260 def_bool y
1261 depends on X86_32 && !NUMA
1262
1263config ARCH_DISCONTIGMEM_ENABLE
1264 def_bool y
1265 depends on NUMA && X86_32
1266
1267config ARCH_DISCONTIGMEM_DEFAULT
1268 def_bool y
1269 depends on NUMA && X86_32
1270
1271config ARCH_SPARSEMEM_ENABLE
1272 def_bool y
1273 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1274 select SPARSEMEM_STATIC if X86_32
1275 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1276
1277config ARCH_SPARSEMEM_DEFAULT
1278 def_bool y
1279 depends on X86_64
1280
1281config ARCH_SELECT_MEMORY_MODEL
1282 def_bool y
1283 depends on ARCH_SPARSEMEM_ENABLE
1284
1285config ARCH_MEMORY_PROBE
1286 def_bool X86_64
1287 depends on MEMORY_HOTPLUG
1288
1289config ARCH_PROC_KCORE_TEXT
1290 def_bool y
1291 depends on X86_64 && PROC_KCORE
1292
1293config ILLEGAL_POINTER_VALUE
1294 hex
1295 default 0 if X86_32
1296 default 0xdead000000000000 if X86_64
1297
1298source "mm/Kconfig"
1299
1300config HIGHPTE
1301 bool "Allocate 3rd-level pagetables from highmem"
1302 depends on HIGHMEM
1303 ---help---
1304 The VM uses one page table entry for each page of physical memory.
1305 For systems with a lot of RAM, this can be wasteful of precious
1306 low memory. Setting this option will put user-space page table
1307 entries in high memory.
1308
1309config X86_CHECK_BIOS_CORRUPTION
1310 bool "Check for low memory corruption"
1311 ---help---
1312 Periodically check for memory corruption in low memory, which
1313 is suspected to be caused by BIOS. Even when enabled in the
1314 configuration, it is disabled at runtime. Enable it by
1315 setting "memory_corruption_check=1" on the kernel command
1316 line. By default it scans the low 64k of memory every 60
1317 seconds; see the memory_corruption_check_size and
1318 memory_corruption_check_period parameters in
1319 Documentation/kernel-parameters.txt to adjust this.
1320
1321 When enabled with the default parameters, this option has
1322 almost no overhead, as it reserves a relatively small amount
1323 of memory and scans it infrequently. It both detects corruption
1324 and prevents it from affecting the running system.
1325
1326 It is, however, intended as a diagnostic tool; if repeatable
1327 BIOS-originated corruption always affects the same memory,
1328 you can use memmap= to prevent the kernel from using that
1329 memory.
1330
1331config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1332 bool "Set the default setting of memory_corruption_check"
1333 depends on X86_CHECK_BIOS_CORRUPTION
1334 default y
1335 ---help---
1336 Set whether the default state of memory_corruption_check is
1337 on or off.
1338
1339config X86_RESERVE_LOW
1340 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1341 default 64
1342 range 4 640
1343 ---help---
1344 Specify the amount of low memory to reserve for the BIOS.
1345
1346 The first page contains BIOS data structures that the kernel
1347 must not use, so that page must always be reserved.
1348
1349 By default we reserve the first 64K of physical RAM, as a
1350 number of BIOSes are known to corrupt that memory range
1351 during events such as suspend/resume or monitor cable
1352 insertion, so it must not be used by the kernel.
1353
1354 You can set this to 4 if you are absolutely sure that you
1355 trust the BIOS to get all its memory reservations and usages
1356 right. If you know your BIOS have problems beyond the
1357 default 64K area, you can set this to 640 to avoid using the
1358 entire low memory range.
1359
1360 If you have doubts about the BIOS (e.g. suspend/resume does
1361 not work or there's kernel crashes after certain hardware
1362 hotplug events) then you might want to enable
1363 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1364 typical corruption patterns.
1365
1366 Leave this to the default value of 64 if you are unsure.
1367
1368config MATH_EMULATION
1369 bool
1370 prompt "Math emulation" if X86_32
1371 ---help---
1372 Linux can emulate a math coprocessor (used for floating point
1373 operations) if you don't have one. 486DX and Pentium processors have
1374 a math coprocessor built in, 486SX and 386 do not, unless you added
1375 a 487DX or 387, respectively. (The messages during boot time can
1376 give you some hints here ["man dmesg"].) Everyone needs either a
1377 coprocessor or this emulation.
1378
1379 If you don't have a math coprocessor, you need to say Y here; if you
1380 say Y here even though you have a coprocessor, the coprocessor will
1381 be used nevertheless. (This behavior can be changed with the kernel
1382 command line option "no387", which comes handy if your coprocessor
1383 is broken. Try "man bootparam" or see the documentation of your boot
1384 loader (lilo or loadlin) about how to pass options to the kernel at
1385 boot time.) This means that it is a good idea to say Y here if you
1386 intend to use this kernel on different machines.
1387
1388 More information about the internals of the Linux math coprocessor
1389 emulation can be found in <file:arch/x86/math-emu/README>.
1390
1391 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1392 kernel, it won't hurt.
1393
1394config MTRR
1395 def_bool y
1396 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1397 ---help---
1398 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1399 the Memory Type Range Registers (MTRRs) may be used to control
1400 processor access to memory ranges. This is most useful if you have
1401 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1402 allows bus write transfers to be combined into a larger transfer
1403 before bursting over the PCI/AGP bus. This can increase performance
1404 of image write operations 2.5 times or more. Saying Y here creates a
1405 /proc/mtrr file which may be used to manipulate your processor's
1406 MTRRs. Typically the X server should use this.
1407
1408 This code has a reasonably generic interface so that similar
1409 control registers on other processors can be easily supported
1410 as well:
1411
1412 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1413 Registers (ARRs) which provide a similar functionality to MTRRs. For
1414 these, the ARRs are used to emulate the MTRRs.
1415 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1416 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1417 write-combining. All of these processors are supported by this code
1418 and it makes sense to say Y here if you have one of them.
1419
1420 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1421 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1422 can lead to all sorts of problems, so it's good to say Y here.
1423
1424 You can safely say Y even if your machine doesn't have MTRRs, you'll
1425 just add about 9 KB to your kernel.
1426
1427 See <file:Documentation/x86/mtrr.txt> for more information.
1428
1429config MTRR_SANITIZER
1430 def_bool y
1431 prompt "MTRR cleanup support"
1432 depends on MTRR
1433 ---help---
1434 Convert MTRR layout from continuous to discrete, so X drivers can
1435 add writeback entries.
1436
1437 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1438 The largest mtrr entry size for a continuous block can be set with
1439 mtrr_chunk_size.
1440
1441 If unsure, say Y.
1442
1443config MTRR_SANITIZER_ENABLE_DEFAULT
1444 int "MTRR cleanup enable value (0-1)"
1445 range 0 1
1446 default "0"
1447 depends on MTRR_SANITIZER
1448 ---help---
1449 Enable mtrr cleanup default value
1450
1451config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1452 int "MTRR cleanup spare reg num (0-7)"
1453 range 0 7
1454 default "1"
1455 depends on MTRR_SANITIZER
1456 ---help---
1457 mtrr cleanup spare entries default, it can be changed via
1458 mtrr_spare_reg_nr=N on the kernel command line.
1459
1460config X86_PAT
1461 def_bool y
1462 prompt "x86 PAT support" if EXPERT
1463 depends on MTRR
1464 ---help---
1465 Use PAT attributes to setup page level cache control.
1466
1467 PATs are the modern equivalents of MTRRs and are much more
1468 flexible than MTRRs.
1469
1470 Say N here if you see bootup problems (boot crash, boot hang,
1471 spontaneous reboots) or a non-working video driver.
1472
1473 If unsure, say Y.
1474
1475config ARCH_USES_PG_UNCACHED
1476 def_bool y
1477 depends on X86_PAT
1478
1479config ARCH_RANDOM
1480 def_bool y
1481 prompt "x86 architectural random number generator" if EXPERT
1482 ---help---
1483 Enable the x86 architectural RDRAND instruction
1484 (Intel Bull Mountain technology) to generate random numbers.
1485 If supported, this is a high bandwidth, cryptographically
1486 secure hardware random number generator.
1487
1488config EFI
1489 bool "EFI runtime service support"
1490 depends on ACPI
1491 ---help---
1492 This enables the kernel to use EFI runtime services that are
1493 available (such as the EFI variable services).
1494
1495 This option is only useful on systems that have EFI firmware.
1496 In addition, you should use the latest ELILO loader available
1497 at <http://elilo.sourceforge.net> in order to take advantage
1498 of EFI runtime services. However, even with this option, the
1499 resultant kernel should continue to boot on existing non-EFI
1500 platforms.
1501
1502config EFI_STUB
1503 bool "EFI stub support"
1504 depends on EFI
1505 ---help---
1506 This kernel feature allows a bzImage to be loaded directly
1507 by EFI firmware without the use of a bootloader.
1508
1509 See Documentation/x86/efi-stub.txt for more information.
1510
1511config SECCOMP
1512 def_bool y
1513 prompt "Enable seccomp to safely compute untrusted bytecode"
1514 ---help---
1515 This kernel feature is useful for number crunching applications
1516 that may need to compute untrusted bytecode during their
1517 execution. By using pipes or other transports made available to
1518 the process as file descriptors supporting the read/write
1519 syscalls, it's possible to isolate those applications in
1520 their own address space using seccomp. Once seccomp is
1521 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1522 and the task is only allowed to execute a few safe syscalls
1523 defined by each seccomp mode.
1524
1525 If unsure, say Y. Only embedded should say N here.
1526
1527config CC_STACKPROTECTOR
1528 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1529 ---help---
1530 This option turns on the -fstack-protector GCC feature. This
1531 feature puts, at the beginning of functions, a canary value on
1532 the stack just before the return address, and validates
1533 the value just before actually returning. Stack based buffer
1534 overflows (that need to overwrite this return address) now also
1535 overwrite the canary, which gets detected and the attack is then
1536 neutralized via a kernel panic.
1537
1538 This feature requires gcc version 4.2 or above, or a distribution
1539 gcc with the feature backported. Older versions are automatically
1540 detected and for those versions, this configuration option is
1541 ignored. (and a warning is printed during bootup)
1542
1543source kernel/Kconfig.hz
1544
1545config KEXEC
1546 bool "kexec system call"
1547 ---help---
1548 kexec is a system call that implements the ability to shutdown your
1549 current kernel, and to start another kernel. It is like a reboot
1550 but it is independent of the system firmware. And like a reboot
1551 you can start any kernel with it, not just Linux.
1552
1553 The name comes from the similarity to the exec system call.
1554
1555 It is an ongoing process to be certain the hardware in a machine
1556 is properly shutdown, so do not be surprised if this code does not
1557 initially work for you. It may help to enable device hotplugging
1558 support. As of this writing the exact hardware interface is
1559 strongly in flux, so no good recommendation can be made.
1560
1561config CRASH_DUMP
1562 bool "kernel crash dumps"
1563 depends on X86_64 || (X86_32 && HIGHMEM)
1564 ---help---
1565 Generate crash dump after being started by kexec.
1566 This should be normally only set in special crash dump kernels
1567 which are loaded in the main kernel with kexec-tools into
1568 a specially reserved region and then later executed after
1569 a crash by kdump/kexec. The crash dump kernel must be compiled
1570 to a memory address not used by the main kernel or BIOS using
1571 PHYSICAL_START, or it must be built as a relocatable image
1572 (CONFIG_RELOCATABLE=y).
1573 For more details see Documentation/kdump/kdump.txt
1574
1575config KEXEC_JUMP
1576 bool "kexec jump (EXPERIMENTAL)"
1577 depends on EXPERIMENTAL
1578 depends on KEXEC && HIBERNATION
1579 ---help---
1580 Jump between original kernel and kexeced kernel and invoke
1581 code in physical address mode via KEXEC
1582
1583config PHYSICAL_START
1584 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1585 default "0x1000000"
1586 ---help---
1587 This gives the physical address where the kernel is loaded.
1588
1589 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1590 bzImage will decompress itself to above physical address and
1591 run from there. Otherwise, bzImage will run from the address where
1592 it has been loaded by the boot loader and will ignore above physical
1593 address.
1594
1595 In normal kdump cases one does not have to set/change this option
1596 as now bzImage can be compiled as a completely relocatable image
1597 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1598 address. This option is mainly useful for the folks who don't want
1599 to use a bzImage for capturing the crash dump and want to use a
1600 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1601 to be specifically compiled to run from a specific memory area
1602 (normally a reserved region) and this option comes handy.
1603
1604 So if you are using bzImage for capturing the crash dump,
1605 leave the value here unchanged to 0x1000000 and set
1606 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1607 for capturing the crash dump change this value to start of
1608 the reserved region. In other words, it can be set based on
1609 the "X" value as specified in the "crashkernel=YM@XM"
1610 command line boot parameter passed to the panic-ed
1611 kernel. Please take a look at Documentation/kdump/kdump.txt
1612 for more details about crash dumps.
1613
1614 Usage of bzImage for capturing the crash dump is recommended as
1615 one does not have to build two kernels. Same kernel can be used
1616 as production kernel and capture kernel. Above option should have
1617 gone away after relocatable bzImage support is introduced. But it
1618 is present because there are users out there who continue to use
1619 vmlinux for dump capture. This option should go away down the
1620 line.
1621
1622 Don't change this unless you know what you are doing.
1623
1624config RELOCATABLE
1625 bool "Build a relocatable kernel"
1626 default y
1627 ---help---
1628 This builds a kernel image that retains relocation information
1629 so it can be loaded someplace besides the default 1MB.
1630 The relocations tend to make the kernel binary about 10% larger,
1631 but are discarded at runtime.
1632
1633 One use is for the kexec on panic case where the recovery kernel
1634 must live at a different physical address than the primary
1635 kernel.
1636
1637 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1638 it has been loaded at and the compile time physical address
1639 (CONFIG_PHYSICAL_START) is ignored.
1640
1641# Relocation on x86-32 needs some additional build support
1642config X86_NEED_RELOCS
1643 def_bool y
1644 depends on X86_32 && RELOCATABLE
1645
1646config PHYSICAL_ALIGN
1647 hex "Alignment value to which kernel should be aligned" if X86_32
1648 default "0x1000000"
1649 range 0x2000 0x1000000
1650 ---help---
1651 This value puts the alignment restrictions on physical address
1652 where kernel is loaded and run from. Kernel is compiled for an
1653 address which meets above alignment restriction.
1654
1655 If bootloader loads the kernel at a non-aligned address and
1656 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1657 address aligned to above value and run from there.
1658
1659 If bootloader loads the kernel at a non-aligned address and
1660 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1661 load address and decompress itself to the address it has been
1662 compiled for and run from there. The address for which kernel is
1663 compiled already meets above alignment restrictions. Hence the
1664 end result is that kernel runs from a physical address meeting
1665 above alignment restrictions.
1666
1667 Don't change this unless you know what you are doing.
1668
1669config HOTPLUG_CPU
1670 bool "Support for hot-pluggable CPUs"
1671 depends on SMP && HOTPLUG
1672 ---help---
1673 Say Y here to allow turning CPUs off and on. CPUs can be
1674 controlled through /sys/devices/system/cpu.
1675 ( Note: power management support will enable this option
1676 automatically on SMP systems. )
1677 Say N if you want to disable CPU hotplug.
1678
1679config COMPAT_VDSO
1680 def_bool y
1681 prompt "Compat VDSO support"
1682 depends on X86_32 || IA32_EMULATION
1683 ---help---
1684 Map the 32-bit VDSO to the predictable old-style address too.
1685
1686 Say N here if you are running a sufficiently recent glibc
1687 version (2.3.3 or later), to remove the high-mapped
1688 VDSO mapping and to exclusively use the randomized VDSO.
1689
1690 If unsure, say Y.
1691
1692config CMDLINE_BOOL
1693 bool "Built-in kernel command line"
1694 ---help---
1695 Allow for specifying boot arguments to the kernel at
1696 build time. On some systems (e.g. embedded ones), it is
1697 necessary or convenient to provide some or all of the
1698 kernel boot arguments with the kernel itself (that is,
1699 to not rely on the boot loader to provide them.)
1700
1701 To compile command line arguments into the kernel,
1702 set this option to 'Y', then fill in the
1703 the boot arguments in CONFIG_CMDLINE.
1704
1705 Systems with fully functional boot loaders (i.e. non-embedded)
1706 should leave this option set to 'N'.
1707
1708config CMDLINE
1709 string "Built-in kernel command string"
1710 depends on CMDLINE_BOOL
1711 default ""
1712 ---help---
1713 Enter arguments here that should be compiled into the kernel
1714 image and used at boot time. If the boot loader provides a
1715 command line at boot time, it is appended to this string to
1716 form the full kernel command line, when the system boots.
1717
1718 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1719 change this behavior.
1720
1721 In most cases, the command line (whether built-in or provided
1722 by the boot loader) should specify the device for the root
1723 file system.
1724
1725config CMDLINE_OVERRIDE
1726 bool "Built-in command line overrides boot loader arguments"
1727 depends on CMDLINE_BOOL
1728 ---help---
1729 Set this option to 'Y' to have the kernel ignore the boot loader
1730 command line, and use ONLY the built-in command line.
1731
1732 This is used to work around broken boot loaders. This should
1733 be set to 'N' under normal conditions.
1734
1735endmenu
1736
1737config ARCH_ENABLE_MEMORY_HOTPLUG
1738 def_bool y
1739 depends on X86_64 || (X86_32 && HIGHMEM)
1740
1741config ARCH_ENABLE_MEMORY_HOTREMOVE
1742 def_bool y
1743 depends on MEMORY_HOTPLUG
1744
1745config USE_PERCPU_NUMA_NODE_ID
1746 def_bool y
1747 depends on NUMA
1748
1749menu "Power management and ACPI options"
1750
1751config ARCH_HIBERNATION_HEADER
1752 def_bool y
1753 depends on X86_64 && HIBERNATION
1754
1755source "kernel/power/Kconfig"
1756
1757source "drivers/acpi/Kconfig"
1758
1759source "drivers/sfi/Kconfig"
1760
1761config X86_APM_BOOT
1762 def_bool y
1763 depends on APM
1764
1765menuconfig APM
1766 tristate "APM (Advanced Power Management) BIOS support"
1767 depends on X86_32 && PM_SLEEP
1768 ---help---
1769 APM is a BIOS specification for saving power using several different
1770 techniques. This is mostly useful for battery powered laptops with
1771 APM compliant BIOSes. If you say Y here, the system time will be
1772 reset after a RESUME operation, the /proc/apm device will provide
1773 battery status information, and user-space programs will receive
1774 notification of APM "events" (e.g. battery status change).
1775
1776 If you select "Y" here, you can disable actual use of the APM
1777 BIOS by passing the "apm=off" option to the kernel at boot time.
1778
1779 Note that the APM support is almost completely disabled for
1780 machines with more than one CPU.
1781
1782 In order to use APM, you will need supporting software. For location
1783 and more information, read <file:Documentation/power/apm-acpi.txt>
1784 and the Battery Powered Linux mini-HOWTO, available from
1785 <http://www.tldp.org/docs.html#howto>.
1786
1787 This driver does not spin down disk drives (see the hdparm(8)
1788 manpage ("man 8 hdparm") for that), and it doesn't turn off
1789 VESA-compliant "green" monitors.
1790
1791 This driver does not support the TI 4000M TravelMate and the ACER
1792 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1793 desktop machines also don't have compliant BIOSes, and this driver
1794 may cause those machines to panic during the boot phase.
1795
1796 Generally, if you don't have a battery in your machine, there isn't
1797 much point in using this driver and you should say N. If you get
1798 random kernel OOPSes or reboots that don't seem to be related to
1799 anything, try disabling/enabling this option (or disabling/enabling
1800 APM in your BIOS).
1801
1802 Some other things you should try when experiencing seemingly random,
1803 "weird" problems:
1804
1805 1) make sure that you have enough swap space and that it is
1806 enabled.
1807 2) pass the "no-hlt" option to the kernel
1808 3) switch on floating point emulation in the kernel and pass
1809 the "no387" option to the kernel
1810 4) pass the "floppy=nodma" option to the kernel
1811 5) pass the "mem=4M" option to the kernel (thereby disabling
1812 all but the first 4 MB of RAM)
1813 6) make sure that the CPU is not over clocked.
1814 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1815 8) disable the cache from your BIOS settings
1816 9) install a fan for the video card or exchange video RAM
1817 10) install a better fan for the CPU
1818 11) exchange RAM chips
1819 12) exchange the motherboard.
1820
1821 To compile this driver as a module, choose M here: the
1822 module will be called apm.
1823
1824if APM
1825
1826config APM_IGNORE_USER_SUSPEND
1827 bool "Ignore USER SUSPEND"
1828 ---help---
1829 This option will ignore USER SUSPEND requests. On machines with a
1830 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1831 series notebooks, it is necessary to say Y because of a BIOS bug.
1832
1833config APM_DO_ENABLE
1834 bool "Enable PM at boot time"
1835 ---help---
1836 Enable APM features at boot time. From page 36 of the APM BIOS
1837 specification: "When disabled, the APM BIOS does not automatically
1838 power manage devices, enter the Standby State, enter the Suspend
1839 State, or take power saving steps in response to CPU Idle calls."
1840 This driver will make CPU Idle calls when Linux is idle (unless this
1841 feature is turned off -- see "Do CPU IDLE calls", below). This
1842 should always save battery power, but more complicated APM features
1843 will be dependent on your BIOS implementation. You may need to turn
1844 this option off if your computer hangs at boot time when using APM
1845 support, or if it beeps continuously instead of suspending. Turn
1846 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1847 T400CDT. This is off by default since most machines do fine without
1848 this feature.
1849
1850config APM_CPU_IDLE
1851 bool "Make CPU Idle calls when idle"
1852 ---help---
1853 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1854 On some machines, this can activate improved power savings, such as
1855 a slowed CPU clock rate, when the machine is idle. These idle calls
1856 are made after the idle loop has run for some length of time (e.g.,
1857 333 mS). On some machines, this will cause a hang at boot time or
1858 whenever the CPU becomes idle. (On machines with more than one CPU,
1859 this option does nothing.)
1860
1861config APM_DISPLAY_BLANK
1862 bool "Enable console blanking using APM"
1863 ---help---
1864 Enable console blanking using the APM. Some laptops can use this to
1865 turn off the LCD backlight when the screen blanker of the Linux
1866 virtual console blanks the screen. Note that this is only used by
1867 the virtual console screen blanker, and won't turn off the backlight
1868 when using the X Window system. This also doesn't have anything to
1869 do with your VESA-compliant power-saving monitor. Further, this
1870 option doesn't work for all laptops -- it might not turn off your
1871 backlight at all, or it might print a lot of errors to the console,
1872 especially if you are using gpm.
1873
1874config APM_ALLOW_INTS
1875 bool "Allow interrupts during APM BIOS calls"
1876 ---help---
1877 Normally we disable external interrupts while we are making calls to
1878 the APM BIOS as a measure to lessen the effects of a badly behaving
1879 BIOS implementation. The BIOS should reenable interrupts if it
1880 needs to. Unfortunately, some BIOSes do not -- especially those in
1881 many of the newer IBM Thinkpads. If you experience hangs when you
1882 suspend, try setting this to Y. Otherwise, say N.
1883
1884endif # APM
1885
1886source "drivers/cpufreq/Kconfig"
1887
1888source "drivers/cpuidle/Kconfig"
1889
1890source "drivers/idle/Kconfig"
1891
1892endmenu
1893
1894
1895menu "Bus options (PCI etc.)"
1896
1897config PCI
1898 bool "PCI support"
1899 default y
1900 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1901 ---help---
1902 Find out whether you have a PCI motherboard. PCI is the name of a
1903 bus system, i.e. the way the CPU talks to the other stuff inside
1904 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1905 VESA. If you have PCI, say Y, otherwise N.
1906
1907choice
1908 prompt "PCI access mode"
1909 depends on X86_32 && PCI
1910 default PCI_GOANY
1911 ---help---
1912 On PCI systems, the BIOS can be used to detect the PCI devices and
1913 determine their configuration. However, some old PCI motherboards
1914 have BIOS bugs and may crash if this is done. Also, some embedded
1915 PCI-based systems don't have any BIOS at all. Linux can also try to
1916 detect the PCI hardware directly without using the BIOS.
1917
1918 With this option, you can specify how Linux should detect the
1919 PCI devices. If you choose "BIOS", the BIOS will be used,
1920 if you choose "Direct", the BIOS won't be used, and if you
1921 choose "MMConfig", then PCI Express MMCONFIG will be used.
1922 If you choose "Any", the kernel will try MMCONFIG, then the
1923 direct access method and falls back to the BIOS if that doesn't
1924 work. If unsure, go with the default, which is "Any".
1925
1926config PCI_GOBIOS
1927 bool "BIOS"
1928
1929config PCI_GOMMCONFIG
1930 bool "MMConfig"
1931
1932config PCI_GODIRECT
1933 bool "Direct"
1934
1935config PCI_GOOLPC
1936 bool "OLPC XO-1"
1937 depends on OLPC
1938
1939config PCI_GOANY
1940 bool "Any"
1941
1942endchoice
1943
1944config PCI_BIOS
1945 def_bool y
1946 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1947
1948# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1949config PCI_DIRECT
1950 def_bool y
1951 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
1952
1953config PCI_MMCONFIG
1954 def_bool y
1955 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
1956
1957config PCI_OLPC
1958 def_bool y
1959 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1960
1961config PCI_XEN
1962 def_bool y
1963 depends on PCI && XEN
1964 select SWIOTLB_XEN
1965
1966config PCI_DOMAINS
1967 def_bool y
1968 depends on PCI
1969
1970config PCI_MMCONFIG
1971 bool "Support mmconfig PCI config space access"
1972 depends on X86_64 && PCI && ACPI
1973
1974config PCI_CNB20LE_QUIRK
1975 bool "Read CNB20LE Host Bridge Windows" if EXPERT
1976 default n
1977 depends on PCI && EXPERIMENTAL
1978 help
1979 Read the PCI windows out of the CNB20LE host bridge. This allows
1980 PCI hotplug to work on systems with the CNB20LE chipset which do
1981 not have ACPI.
1982
1983 There's no public spec for this chipset, and this functionality
1984 is known to be incomplete.
1985
1986 You should say N unless you know you need this.
1987
1988source "drivers/pci/pcie/Kconfig"
1989
1990source "drivers/pci/Kconfig"
1991
1992# x86_64 have no ISA slots, but can have ISA-style DMA.
1993config ISA_DMA_API
1994 bool "ISA-style DMA support" if (X86_64 && EXPERT)
1995 default y
1996 help
1997 Enables ISA-style DMA support for devices requiring such controllers.
1998 If unsure, say Y.
1999
2000if X86_32
2001
2002config ISA
2003 bool "ISA support"
2004 ---help---
2005 Find out whether you have ISA slots on your motherboard. ISA is the
2006 name of a bus system, i.e. the way the CPU talks to the other stuff
2007 inside your box. Other bus systems are PCI, EISA, MicroChannel
2008 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2009 newer boards don't support it. If you have ISA, say Y, otherwise N.
2010
2011config EISA
2012 bool "EISA support"
2013 depends on ISA
2014 ---help---
2015 The Extended Industry Standard Architecture (EISA) bus was
2016 developed as an open alternative to the IBM MicroChannel bus.
2017
2018 The EISA bus provided some of the features of the IBM MicroChannel
2019 bus while maintaining backward compatibility with cards made for
2020 the older ISA bus. The EISA bus saw limited use between 1988 and
2021 1995 when it was made obsolete by the PCI bus.
2022
2023 Say Y here if you are building a kernel for an EISA-based machine.
2024
2025 Otherwise, say N.
2026
2027source "drivers/eisa/Kconfig"
2028
2029config SCx200
2030 tristate "NatSemi SCx200 support"
2031 ---help---
2032 This provides basic support for National Semiconductor's
2033 (now AMD's) Geode processors. The driver probes for the
2034 PCI-IDs of several on-chip devices, so its a good dependency
2035 for other scx200_* drivers.
2036
2037 If compiled as a module, the driver is named scx200.
2038
2039config SCx200HR_TIMER
2040 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2041 depends on SCx200
2042 default y
2043 ---help---
2044 This driver provides a clocksource built upon the on-chip
2045 27MHz high-resolution timer. Its also a workaround for
2046 NSC Geode SC-1100's buggy TSC, which loses time when the
2047 processor goes idle (as is done by the scheduler). The
2048 other workaround is idle=poll boot option.
2049
2050config OLPC
2051 bool "One Laptop Per Child support"
2052 depends on !X86_PAE
2053 select GPIOLIB
2054 select OF
2055 select OF_PROMTREE
2056 select IRQ_DOMAIN
2057 ---help---
2058 Add support for detecting the unique features of the OLPC
2059 XO hardware.
2060
2061config OLPC_XO1_PM
2062 bool "OLPC XO-1 Power Management"
2063 depends on OLPC && MFD_CS5535 && PM_SLEEP
2064 select MFD_CORE
2065 ---help---
2066 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2067
2068config OLPC_XO1_RTC
2069 bool "OLPC XO-1 Real Time Clock"
2070 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2071 ---help---
2072 Add support for the XO-1 real time clock, which can be used as a
2073 programmable wakeup source.
2074
2075config OLPC_XO1_SCI
2076 bool "OLPC XO-1 SCI extras"
2077 depends on OLPC && OLPC_XO1_PM
2078 select POWER_SUPPLY
2079 select GPIO_CS5535
2080 select MFD_CORE
2081 ---help---
2082 Add support for SCI-based features of the OLPC XO-1 laptop:
2083 - EC-driven system wakeups
2084 - Power button
2085 - Ebook switch
2086 - Lid switch
2087 - AC adapter status updates
2088 - Battery status updates
2089
2090config OLPC_XO15_SCI
2091 bool "OLPC XO-1.5 SCI extras"
2092 depends on OLPC && ACPI
2093 select POWER_SUPPLY
2094 ---help---
2095 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2096 - EC-driven system wakeups
2097 - AC adapter status updates
2098 - Battery status updates
2099
2100config ALIX
2101 bool "PCEngines ALIX System Support (LED setup)"
2102 select GPIOLIB
2103 ---help---
2104 This option enables system support for the PCEngines ALIX.
2105 At present this just sets up LEDs for GPIO control on
2106 ALIX2/3/6 boards. However, other system specific setup should
2107 get added here.
2108
2109 Note: You must still enable the drivers for GPIO and LED support
2110 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2111
2112 Note: You have to set alix.force=1 for boards with Award BIOS.
2113
2114config NET5501
2115 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2116 select GPIOLIB
2117 ---help---
2118 This option enables system support for the Soekris Engineering net5501.
2119
2120config GEOS
2121 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2122 select GPIOLIB
2123 depends on DMI
2124 ---help---
2125 This option enables system support for the Traverse Technologies GEOS.
2126
2127endif # X86_32
2128
2129config AMD_NB
2130 def_bool y
2131 depends on CPU_SUP_AMD && PCI
2132
2133source "drivers/pcmcia/Kconfig"
2134
2135source "drivers/pci/hotplug/Kconfig"
2136
2137config RAPIDIO
2138 bool "RapidIO support"
2139 depends on PCI
2140 default n
2141 help
2142 If you say Y here, the kernel will include drivers and
2143 infrastructure code to support RapidIO interconnect devices.
2144
2145source "drivers/rapidio/Kconfig"
2146
2147endmenu
2148
2149
2150menu "Executable file formats / Emulations"
2151
2152source "fs/Kconfig.binfmt"
2153
2154config IA32_EMULATION
2155 bool "IA32 Emulation"
2156 depends on X86_64
2157 select COMPAT_BINFMT_ELF
2158 ---help---
2159 Include code to run legacy 32-bit programs under a
2160 64-bit kernel. You should likely turn this on, unless you're
2161 100% sure that you don't have any 32-bit programs left.
2162
2163config IA32_AOUT
2164 tristate "IA32 a.out support"
2165 depends on IA32_EMULATION
2166 ---help---
2167 Support old a.out binaries in the 32bit emulation.
2168
2169config X86_X32
2170 bool "x32 ABI for 64-bit mode (EXPERIMENTAL)"
2171 depends on X86_64 && IA32_EMULATION && EXPERIMENTAL
2172 ---help---
2173 Include code to run binaries for the x32 native 32-bit ABI
2174 for 64-bit processors. An x32 process gets access to the
2175 full 64-bit register file and wide data path while leaving
2176 pointers at 32 bits for smaller memory footprint.
2177
2178 You will need a recent binutils (2.22 or later) with
2179 elf32_x86_64 support enabled to compile a kernel with this
2180 option set.
2181
2182config COMPAT
2183 def_bool y
2184 depends on IA32_EMULATION || X86_X32
2185 select ARCH_WANT_OLD_COMPAT_IPC
2186
2187config COMPAT_FOR_U64_ALIGNMENT
2188 def_bool COMPAT
2189 depends on X86_64
2190
2191config SYSVIPC_COMPAT
2192 def_bool y
2193 depends on COMPAT && SYSVIPC
2194
2195config KEYS_COMPAT
2196 bool
2197 depends on COMPAT && KEYS
2198 default y
2199
2200endmenu
2201
2202
2203config HAVE_ATOMIC_IOMAP
2204 def_bool y
2205 depends on X86_32
2206
2207config HAVE_TEXT_POKE_SMP
2208 bool
2209 select STOP_MACHINE if SMP
2210
2211config X86_DEV_DMA_OPS
2212 bool
2213 depends on X86_64 || STA2X11
2214
2215config X86_DMA_REMAP
2216 bool
2217 depends on STA2X11
2218
2219source "net/Kconfig"
2220
2221source "drivers/Kconfig"
2222
2223source "drivers/firmware/Kconfig"
2224
2225source "fs/Kconfig"
2226
2227source "arch/x86/Kconfig.debug"
2228
2229source "security/Kconfig"
2230
2231source "crypto/Kconfig"
2232
2233source "arch/x86/kvm/Kconfig"
2234
2235source "lib/Kconfig"
1# Select 32 or 64 bit
2config 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
9config X86_32
10 def_bool !64BIT
11 select CLKSRC_I8253
12
13config X86_64
14 def_bool 64BIT
15
16### Arch settings
17config X86
18 def_bool y
19 select HAVE_AOUT if X86_32
20 select HAVE_UNSTABLE_SCHED_CLOCK
21 select HAVE_IDE
22 select HAVE_OPROFILE
23 select HAVE_PCSPKR_PLATFORM
24 select HAVE_PERF_EVENTS
25 select HAVE_IRQ_WORK
26 select HAVE_IOREMAP_PROT
27 select HAVE_KPROBES
28 select HAVE_MEMBLOCK
29 select ARCH_WANT_OPTIONAL_GPIOLIB
30 select ARCH_WANT_FRAME_POINTERS
31 select HAVE_DMA_ATTRS
32 select HAVE_KRETPROBES
33 select HAVE_OPTPROBES
34 select HAVE_FTRACE_MCOUNT_RECORD
35 select HAVE_C_RECORDMCOUNT
36 select HAVE_DYNAMIC_FTRACE
37 select HAVE_FUNCTION_TRACER
38 select HAVE_FUNCTION_GRAPH_TRACER
39 select HAVE_FUNCTION_GRAPH_FP_TEST
40 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
41 select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
42 select HAVE_SYSCALL_TRACEPOINTS
43 select HAVE_KVM
44 select HAVE_ARCH_KGDB
45 select HAVE_ARCH_TRACEHOOK
46 select HAVE_GENERIC_DMA_COHERENT if X86_32
47 select HAVE_EFFICIENT_UNALIGNED_ACCESS
48 select USER_STACKTRACE_SUPPORT
49 select HAVE_REGS_AND_STACK_ACCESS_API
50 select HAVE_DMA_API_DEBUG
51 select HAVE_KERNEL_GZIP
52 select HAVE_KERNEL_BZIP2
53 select HAVE_KERNEL_LZMA
54 select HAVE_KERNEL_XZ
55 select HAVE_KERNEL_LZO
56 select HAVE_HW_BREAKPOINT
57 select HAVE_MIXED_BREAKPOINTS_REGS
58 select PERF_EVENTS
59 select HAVE_PERF_EVENTS_NMI
60 select ANON_INODES
61 select HAVE_ARCH_KMEMCHECK
62 select HAVE_USER_RETURN_NOTIFIER
63 select HAVE_ARCH_JUMP_LABEL
64 select HAVE_TEXT_POKE_SMP
65 select HAVE_GENERIC_HARDIRQS
66 select HAVE_SPARSE_IRQ
67 select GENERIC_FIND_FIRST_BIT
68 select GENERIC_IRQ_PROBE
69 select GENERIC_PENDING_IRQ if SMP
70 select GENERIC_IRQ_SHOW
71 select IRQ_FORCED_THREADING
72 select USE_GENERIC_SMP_HELPERS if SMP
73 select HAVE_BPF_JIT if (X86_64 && NET)
74 select CLKEVT_I8253
75 select ARCH_HAVE_NMI_SAFE_CMPXCHG
76
77config INSTRUCTION_DECODER
78 def_bool (KPROBES || PERF_EVENTS)
79
80config OUTPUT_FORMAT
81 string
82 default "elf32-i386" if X86_32
83 default "elf64-x86-64" if X86_64
84
85config ARCH_DEFCONFIG
86 string
87 default "arch/x86/configs/i386_defconfig" if X86_32
88 default "arch/x86/configs/x86_64_defconfig" if X86_64
89
90config GENERIC_CMOS_UPDATE
91 def_bool y
92
93config CLOCKSOURCE_WATCHDOG
94 def_bool y
95
96config GENERIC_CLOCKEVENTS
97 def_bool y
98
99config ARCH_CLOCKSOURCE_DATA
100 def_bool y
101 depends on X86_64
102
103config GENERIC_CLOCKEVENTS_BROADCAST
104 def_bool y
105 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
106
107config LOCKDEP_SUPPORT
108 def_bool y
109
110config STACKTRACE_SUPPORT
111 def_bool y
112
113config HAVE_LATENCYTOP_SUPPORT
114 def_bool y
115
116config MMU
117 def_bool y
118
119config ZONE_DMA
120 bool "DMA memory allocation support" if EXPERT
121 default y
122 help
123 DMA memory allocation support allows devices with less than 32-bit
124 addressing to allocate within the first 16MB of address space.
125 Disable if no such devices will be used.
126
127 If unsure, say Y.
128
129config SBUS
130 bool
131
132config NEED_DMA_MAP_STATE
133 def_bool (X86_64 || DMAR || DMA_API_DEBUG)
134
135config NEED_SG_DMA_LENGTH
136 def_bool y
137
138config GENERIC_ISA_DMA
139 def_bool ISA_DMA_API
140
141config GENERIC_IOMAP
142 def_bool y
143
144config GENERIC_BUG
145 def_bool y
146 depends on BUG
147 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
148
149config GENERIC_BUG_RELATIVE_POINTERS
150 bool
151
152config GENERIC_HWEIGHT
153 def_bool y
154
155config GENERIC_GPIO
156 bool
157
158config ARCH_MAY_HAVE_PC_FDC
159 def_bool ISA_DMA_API
160
161config RWSEM_GENERIC_SPINLOCK
162 def_bool !X86_XADD
163
164config RWSEM_XCHGADD_ALGORITHM
165 def_bool X86_XADD
166
167config ARCH_HAS_CPU_IDLE_WAIT
168 def_bool y
169
170config GENERIC_CALIBRATE_DELAY
171 def_bool y
172
173config GENERIC_TIME_VSYSCALL
174 bool
175 default X86_64
176
177config ARCH_HAS_CPU_RELAX
178 def_bool y
179
180config ARCH_HAS_DEFAULT_IDLE
181 def_bool y
182
183config ARCH_HAS_CACHE_LINE_SIZE
184 def_bool y
185
186config HAVE_SETUP_PER_CPU_AREA
187 def_bool y
188
189config NEED_PER_CPU_EMBED_FIRST_CHUNK
190 def_bool y
191
192config NEED_PER_CPU_PAGE_FIRST_CHUNK
193 def_bool y
194
195config HAVE_CPUMASK_OF_CPU_MAP
196 def_bool X86_64_SMP
197
198config ARCH_HIBERNATION_POSSIBLE
199 def_bool y
200
201config ARCH_SUSPEND_POSSIBLE
202 def_bool y
203
204config ZONE_DMA32
205 bool
206 default X86_64
207
208config ARCH_POPULATES_NODE_MAP
209 def_bool y
210
211config AUDIT_ARCH
212 bool
213 default X86_64
214
215config ARCH_SUPPORTS_OPTIMIZED_INLINING
216 def_bool y
217
218config ARCH_SUPPORTS_DEBUG_PAGEALLOC
219 def_bool y
220
221config HAVE_INTEL_TXT
222 def_bool y
223 depends on EXPERIMENTAL && DMAR && ACPI
224
225config X86_32_SMP
226 def_bool y
227 depends on X86_32 && SMP
228
229config X86_64_SMP
230 def_bool y
231 depends on X86_64 && SMP
232
233config X86_HT
234 def_bool y
235 depends on SMP
236
237config X86_32_LAZY_GS
238 def_bool y
239 depends on X86_32 && !CC_STACKPROTECTOR
240
241config ARCH_HWEIGHT_CFLAGS
242 string
243 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
244 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
245
246config KTIME_SCALAR
247 def_bool X86_32
248
249config ARCH_CPU_PROBE_RELEASE
250 def_bool y
251 depends on HOTPLUG_CPU
252
253source "init/Kconfig"
254source "kernel/Kconfig.freezer"
255
256menu "Processor type and features"
257
258source "kernel/time/Kconfig"
259
260config SMP
261 bool "Symmetric multi-processing support"
262 ---help---
263 This enables support for systems with more than one CPU. If you have
264 a system with only one CPU, like most personal computers, say N. If
265 you have a system with more than one CPU, say Y.
266
267 If you say N here, the kernel will run on single and multiprocessor
268 machines, but will use only one CPU of a multiprocessor machine. If
269 you say Y here, the kernel will run on many, but not all,
270 singleprocessor machines. On a singleprocessor machine, the kernel
271 will run faster if you say N here.
272
273 Note that if you say Y here and choose architecture "586" or
274 "Pentium" under "Processor family", the kernel will not work on 486
275 architectures. Similarly, multiprocessor kernels for the "PPro"
276 architecture may not work on all Pentium based boards.
277
278 People using multiprocessor machines who say Y here should also say
279 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
280 Management" code will be disabled if you say Y here.
281
282 See also <file:Documentation/i386/IO-APIC.txt>,
283 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
284 <http://www.tldp.org/docs.html#howto>.
285
286 If you don't know what to do here, say N.
287
288config X86_X2APIC
289 bool "Support x2apic"
290 depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
291 ---help---
292 This enables x2apic support on CPUs that have this feature.
293
294 This allows 32-bit apic IDs (so it can support very large systems),
295 and accesses the local apic via MSRs not via mmio.
296
297 If you don't know what to do here, say N.
298
299config X86_MPPARSE
300 bool "Enable MPS table" if ACPI
301 default y
302 depends on X86_LOCAL_APIC
303 ---help---
304 For old smp systems that do not have proper acpi support. Newer systems
305 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
306
307config X86_BIGSMP
308 bool "Support for big SMP systems with more than 8 CPUs"
309 depends on X86_32 && SMP
310 ---help---
311 This option is needed for the systems that have more than 8 CPUs
312
313if X86_32
314config X86_EXTENDED_PLATFORM
315 bool "Support for extended (non-PC) x86 platforms"
316 default y
317 ---help---
318 If you disable this option then the kernel will only support
319 standard PC platforms. (which covers the vast majority of
320 systems out there.)
321
322 If you enable this option then you'll be able to select support
323 for the following (non-PC) 32 bit x86 platforms:
324 AMD Elan
325 NUMAQ (IBM/Sequent)
326 RDC R-321x SoC
327 SGI 320/540 (Visual Workstation)
328 Summit/EXA (IBM x440)
329 Unisys ES7000 IA32 series
330 Moorestown MID devices
331
332 If you have one of these systems, or if you want to build a
333 generic distribution kernel, say Y here - otherwise say N.
334endif
335
336if X86_64
337config X86_EXTENDED_PLATFORM
338 bool "Support for extended (non-PC) x86 platforms"
339 default y
340 ---help---
341 If you disable this option then the kernel will only support
342 standard PC platforms. (which covers the vast majority of
343 systems out there.)
344
345 If you enable this option then you'll be able to select support
346 for the following (non-PC) 64 bit x86 platforms:
347 ScaleMP vSMP
348 SGI Ultraviolet
349
350 If you have one of these systems, or if you want to build a
351 generic distribution kernel, say Y here - otherwise say N.
352endif
353# This is an alphabetically sorted list of 64 bit extended platforms
354# Please maintain the alphabetic order if and when there are additions
355
356config X86_VSMP
357 bool "ScaleMP vSMP"
358 select PARAVIRT_GUEST
359 select PARAVIRT
360 depends on X86_64 && PCI
361 depends on X86_EXTENDED_PLATFORM
362 ---help---
363 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
364 supposed to run on these EM64T-based machines. Only choose this option
365 if you have one of these machines.
366
367config X86_UV
368 bool "SGI Ultraviolet"
369 depends on X86_64
370 depends on X86_EXTENDED_PLATFORM
371 depends on NUMA
372 depends on X86_X2APIC
373 ---help---
374 This option is needed in order to support SGI Ultraviolet systems.
375 If you don't have one of these, you should say N here.
376
377# Following is an alphabetically sorted list of 32 bit extended platforms
378# Please maintain the alphabetic order if and when there are additions
379
380config X86_INTEL_CE
381 bool "CE4100 TV platform"
382 depends on PCI
383 depends on PCI_GODIRECT
384 depends on X86_32
385 depends on X86_EXTENDED_PLATFORM
386 select X86_REBOOTFIXUPS
387 select OF
388 select OF_EARLY_FLATTREE
389 ---help---
390 Select for the Intel CE media processor (CE4100) SOC.
391 This option compiles in support for the CE4100 SOC for settop
392 boxes and media devices.
393
394config X86_INTEL_MID
395 bool "Intel MID platform support"
396 depends on X86_32
397 depends on X86_EXTENDED_PLATFORM
398 ---help---
399 Select to build a kernel capable of supporting Intel MID platform
400 systems which do not have the PCI legacy interfaces (Moorestown,
401 Medfield). If you are building for a PC class system say N here.
402
403if X86_INTEL_MID
404
405config X86_MRST
406 bool "Moorestown MID platform"
407 depends on PCI
408 depends on PCI_GOANY
409 depends on X86_IO_APIC
410 select APB_TIMER
411 select I2C
412 select SPI
413 select INTEL_SCU_IPC
414 select X86_PLATFORM_DEVICES
415 ---help---
416 Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
417 Internet Device(MID) platform. Moorestown consists of two chips:
418 Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
419 Unlike standard x86 PCs, Moorestown does not have many legacy devices
420 nor standard legacy replacement devices/features. e.g. Moorestown does
421 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
422
423endif
424
425config X86_RDC321X
426 bool "RDC R-321x SoC"
427 depends on X86_32
428 depends on X86_EXTENDED_PLATFORM
429 select M486
430 select X86_REBOOTFIXUPS
431 ---help---
432 This option is needed for RDC R-321x system-on-chip, also known
433 as R-8610-(G).
434 If you don't have one of these chips, you should say N here.
435
436config X86_32_NON_STANDARD
437 bool "Support non-standard 32-bit SMP architectures"
438 depends on X86_32 && SMP
439 depends on X86_EXTENDED_PLATFORM
440 ---help---
441 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
442 subarchitectures. It is intended for a generic binary kernel.
443 if you select them all, kernel will probe it one by one. and will
444 fallback to default.
445
446# Alphabetically sorted list of Non standard 32 bit platforms
447
448config X86_NUMAQ
449 bool "NUMAQ (IBM/Sequent)"
450 depends on X86_32_NON_STANDARD
451 depends on PCI
452 select NUMA
453 select X86_MPPARSE
454 ---help---
455 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
456 NUMA multiquad box. This changes the way that processors are
457 bootstrapped, and uses Clustered Logical APIC addressing mode instead
458 of Flat Logical. You will need a new lynxer.elf file to flash your
459 firmware with - send email to <Martin.Bligh@us.ibm.com>.
460
461config X86_SUPPORTS_MEMORY_FAILURE
462 def_bool y
463 # MCE code calls memory_failure():
464 depends on X86_MCE
465 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
466 depends on !X86_NUMAQ
467 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
468 depends on X86_64 || !SPARSEMEM
469 select ARCH_SUPPORTS_MEMORY_FAILURE
470
471config X86_VISWS
472 bool "SGI 320/540 (Visual Workstation)"
473 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
474 depends on X86_32_NON_STANDARD
475 ---help---
476 The SGI Visual Workstation series is an IA32-based workstation
477 based on SGI systems chips with some legacy PC hardware attached.
478
479 Say Y here to create a kernel to run on the SGI 320 or 540.
480
481 A kernel compiled for the Visual Workstation will run on general
482 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
483
484config X86_SUMMIT
485 bool "Summit/EXA (IBM x440)"
486 depends on X86_32_NON_STANDARD
487 ---help---
488 This option is needed for IBM systems that use the Summit/EXA chipset.
489 In particular, it is needed for the x440.
490
491config X86_ES7000
492 bool "Unisys ES7000 IA32 series"
493 depends on X86_32_NON_STANDARD && X86_BIGSMP
494 ---help---
495 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
496 supposed to run on an IA32-based Unisys ES7000 system.
497
498config X86_32_IRIS
499 tristate "Eurobraille/Iris poweroff module"
500 depends on X86_32
501 ---help---
502 The Iris machines from EuroBraille do not have APM or ACPI support
503 to shut themselves down properly. A special I/O sequence is
504 needed to do so, which is what this module does at
505 kernel shutdown.
506
507 This is only for Iris machines from EuroBraille.
508
509 If unused, say N.
510
511config SCHED_OMIT_FRAME_POINTER
512 def_bool y
513 prompt "Single-depth WCHAN output"
514 depends on X86
515 ---help---
516 Calculate simpler /proc/<PID>/wchan values. If this option
517 is disabled then wchan values will recurse back to the
518 caller function. This provides more accurate wchan values,
519 at the expense of slightly more scheduling overhead.
520
521 If in doubt, say "Y".
522
523menuconfig PARAVIRT_GUEST
524 bool "Paravirtualized guest support"
525 ---help---
526 Say Y here to get to see options related to running Linux under
527 various hypervisors. This option alone does not add any kernel code.
528
529 If you say N, all options in this submenu will be skipped and disabled.
530
531if PARAVIRT_GUEST
532
533config PARAVIRT_TIME_ACCOUNTING
534 bool "Paravirtual steal time accounting"
535 select PARAVIRT
536 default n
537 ---help---
538 Select this option to enable fine granularity task steal time
539 accounting. Time spent executing other tasks in parallel with
540 the current vCPU is discounted from the vCPU power. To account for
541 that, there can be a small performance impact.
542
543 If in doubt, say N here.
544
545source "arch/x86/xen/Kconfig"
546
547config KVM_CLOCK
548 bool "KVM paravirtualized clock"
549 select PARAVIRT
550 select PARAVIRT_CLOCK
551 ---help---
552 Turning on this option will allow you to run a paravirtualized clock
553 when running over the KVM hypervisor. Instead of relying on a PIT
554 (or probably other) emulation by the underlying device model, the host
555 provides the guest with timing infrastructure such as time of day, and
556 system time
557
558config KVM_GUEST
559 bool "KVM Guest support"
560 select PARAVIRT
561 ---help---
562 This option enables various optimizations for running under the KVM
563 hypervisor.
564
565source "arch/x86/lguest/Kconfig"
566
567config PARAVIRT
568 bool "Enable paravirtualization code"
569 ---help---
570 This changes the kernel so it can modify itself when it is run
571 under a hypervisor, potentially improving performance significantly
572 over full virtualization. However, when run without a hypervisor
573 the kernel is theoretically slower and slightly larger.
574
575config PARAVIRT_SPINLOCKS
576 bool "Paravirtualization layer for spinlocks"
577 depends on PARAVIRT && SMP && EXPERIMENTAL
578 ---help---
579 Paravirtualized spinlocks allow a pvops backend to replace the
580 spinlock implementation with something virtualization-friendly
581 (for example, block the virtual CPU rather than spinning).
582
583 Unfortunately the downside is an up to 5% performance hit on
584 native kernels, with various workloads.
585
586 If you are unsure how to answer this question, answer N.
587
588config PARAVIRT_CLOCK
589 bool
590
591endif
592
593config PARAVIRT_DEBUG
594 bool "paravirt-ops debugging"
595 depends on PARAVIRT && DEBUG_KERNEL
596 ---help---
597 Enable to debug paravirt_ops internals. Specifically, BUG if
598 a paravirt_op is missing when it is called.
599
600config NO_BOOTMEM
601 def_bool y
602
603config MEMTEST
604 bool "Memtest"
605 ---help---
606 This option adds a kernel parameter 'memtest', which allows memtest
607 to be set.
608 memtest=0, mean disabled; -- default
609 memtest=1, mean do 1 test pattern;
610 ...
611 memtest=4, mean do 4 test patterns.
612 If you are unsure how to answer this question, answer N.
613
614config X86_SUMMIT_NUMA
615 def_bool y
616 depends on X86_32 && NUMA && X86_32_NON_STANDARD
617
618config X86_CYCLONE_TIMER
619 def_bool y
620 depends on X86_32_NON_STANDARD
621
622source "arch/x86/Kconfig.cpu"
623
624config HPET_TIMER
625 def_bool X86_64
626 prompt "HPET Timer Support" if X86_32
627 ---help---
628 Use the IA-PC HPET (High Precision Event Timer) to manage
629 time in preference to the PIT and RTC, if a HPET is
630 present.
631 HPET is the next generation timer replacing legacy 8254s.
632 The HPET provides a stable time base on SMP
633 systems, unlike the TSC, but it is more expensive to access,
634 as it is off-chip. You can find the HPET spec at
635 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
636
637 You can safely choose Y here. However, HPET will only be
638 activated if the platform and the BIOS support this feature.
639 Otherwise the 8254 will be used for timing services.
640
641 Choose N to continue using the legacy 8254 timer.
642
643config HPET_EMULATE_RTC
644 def_bool y
645 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
646
647config APB_TIMER
648 def_bool y if MRST
649 prompt "Langwell APB Timer Support" if X86_MRST
650 select DW_APB_TIMER
651 help
652 APB timer is the replacement for 8254, HPET on X86 MID platforms.
653 The APBT provides a stable time base on SMP
654 systems, unlike the TSC, but it is more expensive to access,
655 as it is off-chip. APB timers are always running regardless of CPU
656 C states, they are used as per CPU clockevent device when possible.
657
658# Mark as expert because too many people got it wrong.
659# The code disables itself when not needed.
660config DMI
661 default y
662 bool "Enable DMI scanning" if EXPERT
663 ---help---
664 Enabled scanning of DMI to identify machine quirks. Say Y
665 here unless you have verified that your setup is not
666 affected by entries in the DMI blacklist. Required by PNP
667 BIOS code.
668
669config GART_IOMMU
670 bool "GART IOMMU support" if EXPERT
671 default y
672 select SWIOTLB
673 depends on X86_64 && PCI && AMD_NB
674 ---help---
675 Support for full DMA access of devices with 32bit memory access only
676 on systems with more than 3GB. This is usually needed for USB,
677 sound, many IDE/SATA chipsets and some other devices.
678 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
679 based hardware IOMMU and a software bounce buffer based IOMMU used
680 on Intel systems and as fallback.
681 The code is only active when needed (enough memory and limited
682 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
683 too.
684
685config CALGARY_IOMMU
686 bool "IBM Calgary IOMMU support"
687 select SWIOTLB
688 depends on X86_64 && PCI && EXPERIMENTAL
689 ---help---
690 Support for hardware IOMMUs in IBM's xSeries x366 and x460
691 systems. Needed to run systems with more than 3GB of memory
692 properly with 32-bit PCI devices that do not support DAC
693 (Double Address Cycle). Calgary also supports bus level
694 isolation, where all DMAs pass through the IOMMU. This
695 prevents them from going anywhere except their intended
696 destination. This catches hard-to-find kernel bugs and
697 mis-behaving drivers and devices that do not use the DMA-API
698 properly to set up their DMA buffers. The IOMMU can be
699 turned off at boot time with the iommu=off parameter.
700 Normally the kernel will make the right choice by itself.
701 If unsure, say Y.
702
703config CALGARY_IOMMU_ENABLED_BY_DEFAULT
704 def_bool y
705 prompt "Should Calgary be enabled by default?"
706 depends on CALGARY_IOMMU
707 ---help---
708 Should Calgary be enabled by default? if you choose 'y', Calgary
709 will be used (if it exists). If you choose 'n', Calgary will not be
710 used even if it exists. If you choose 'n' and would like to use
711 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
712 If unsure, say Y.
713
714# need this always selected by IOMMU for the VIA workaround
715config SWIOTLB
716 def_bool y if X86_64
717 ---help---
718 Support for software bounce buffers used on x86-64 systems
719 which don't have a hardware IOMMU (e.g. the current generation
720 of Intel's x86-64 CPUs). Using this PCI devices which can only
721 access 32-bits of memory can be used on systems with more than
722 3 GB of memory. If unsure, say Y.
723
724config IOMMU_HELPER
725 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
726
727config MAXSMP
728 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
729 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
730 select CPUMASK_OFFSTACK
731 ---help---
732 Enable maximum number of CPUS and NUMA Nodes for this architecture.
733 If unsure, say N.
734
735config NR_CPUS
736 int "Maximum number of CPUs" if SMP && !MAXSMP
737 range 2 8 if SMP && X86_32 && !X86_BIGSMP
738 range 2 512 if SMP && !MAXSMP
739 default "1" if !SMP
740 default "4096" if MAXSMP
741 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
742 default "8" if SMP
743 ---help---
744 This allows you to specify the maximum number of CPUs which this
745 kernel will support. The maximum supported value is 512 and the
746 minimum value which makes sense is 2.
747
748 This is purely to save memory - each supported CPU adds
749 approximately eight kilobytes to the kernel image.
750
751config SCHED_SMT
752 bool "SMT (Hyperthreading) scheduler support"
753 depends on X86_HT
754 ---help---
755 SMT scheduler support improves the CPU scheduler's decision making
756 when dealing with Intel Pentium 4 chips with HyperThreading at a
757 cost of slightly increased overhead in some places. If unsure say
758 N here.
759
760config SCHED_MC
761 def_bool y
762 prompt "Multi-core scheduler support"
763 depends on X86_HT
764 ---help---
765 Multi-core scheduler support improves the CPU scheduler's decision
766 making when dealing with multi-core CPU chips at a cost of slightly
767 increased overhead in some places. If unsure say N here.
768
769config IRQ_TIME_ACCOUNTING
770 bool "Fine granularity task level IRQ time accounting"
771 default n
772 ---help---
773 Select this option to enable fine granularity task irq time
774 accounting. This is done by reading a timestamp on each
775 transitions between softirq and hardirq state, so there can be a
776 small performance impact.
777
778 If in doubt, say N here.
779
780source "kernel/Kconfig.preempt"
781
782config X86_UP_APIC
783 bool "Local APIC support on uniprocessors"
784 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
785 ---help---
786 A local APIC (Advanced Programmable Interrupt Controller) is an
787 integrated interrupt controller in the CPU. If you have a single-CPU
788 system which has a processor with a local APIC, you can say Y here to
789 enable and use it. If you say Y here even though your machine doesn't
790 have a local APIC, then the kernel will still run with no slowdown at
791 all. The local APIC supports CPU-generated self-interrupts (timer,
792 performance counters), and the NMI watchdog which detects hard
793 lockups.
794
795config X86_UP_IOAPIC
796 bool "IO-APIC support on uniprocessors"
797 depends on X86_UP_APIC
798 ---help---
799 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
800 SMP-capable replacement for PC-style interrupt controllers. Most
801 SMP systems and many recent uniprocessor systems have one.
802
803 If you have a single-CPU system with an IO-APIC, you can say Y here
804 to use it. If you say Y here even though your machine doesn't have
805 an IO-APIC, then the kernel will still run with no slowdown at all.
806
807config X86_LOCAL_APIC
808 def_bool y
809 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
810
811config X86_IO_APIC
812 def_bool y
813 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC
814
815config X86_VISWS_APIC
816 def_bool y
817 depends on X86_32 && X86_VISWS
818
819config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
820 bool "Reroute for broken boot IRQs"
821 depends on X86_IO_APIC
822 ---help---
823 This option enables a workaround that fixes a source of
824 spurious interrupts. This is recommended when threaded
825 interrupt handling is used on systems where the generation of
826 superfluous "boot interrupts" cannot be disabled.
827
828 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
829 entry in the chipset's IO-APIC is masked (as, e.g. the RT
830 kernel does during interrupt handling). On chipsets where this
831 boot IRQ generation cannot be disabled, this workaround keeps
832 the original IRQ line masked so that only the equivalent "boot
833 IRQ" is delivered to the CPUs. The workaround also tells the
834 kernel to set up the IRQ handler on the boot IRQ line. In this
835 way only one interrupt is delivered to the kernel. Otherwise
836 the spurious second interrupt may cause the kernel to bring
837 down (vital) interrupt lines.
838
839 Only affects "broken" chipsets. Interrupt sharing may be
840 increased on these systems.
841
842config X86_MCE
843 bool "Machine Check / overheating reporting"
844 ---help---
845 Machine Check support allows the processor to notify the
846 kernel if it detects a problem (e.g. overheating, data corruption).
847 The action the kernel takes depends on the severity of the problem,
848 ranging from warning messages to halting the machine.
849
850config X86_MCE_INTEL
851 def_bool y
852 prompt "Intel MCE features"
853 depends on X86_MCE && X86_LOCAL_APIC
854 ---help---
855 Additional support for intel specific MCE features such as
856 the thermal monitor.
857
858config X86_MCE_AMD
859 def_bool y
860 prompt "AMD MCE features"
861 depends on X86_MCE && X86_LOCAL_APIC
862 ---help---
863 Additional support for AMD specific MCE features such as
864 the DRAM Error Threshold.
865
866config X86_ANCIENT_MCE
867 bool "Support for old Pentium 5 / WinChip machine checks"
868 depends on X86_32 && X86_MCE
869 ---help---
870 Include support for machine check handling on old Pentium 5 or WinChip
871 systems. These typically need to be enabled explicitely on the command
872 line.
873
874config X86_MCE_THRESHOLD
875 depends on X86_MCE_AMD || X86_MCE_INTEL
876 def_bool y
877
878config X86_MCE_INJECT
879 depends on X86_MCE
880 tristate "Machine check injector support"
881 ---help---
882 Provide support for injecting machine checks for testing purposes.
883 If you don't know what a machine check is and you don't do kernel
884 QA it is safe to say n.
885
886config X86_THERMAL_VECTOR
887 def_bool y
888 depends on X86_MCE_INTEL
889
890config VM86
891 bool "Enable VM86 support" if EXPERT
892 default y
893 depends on X86_32
894 ---help---
895 This option is required by programs like DOSEMU to run 16-bit legacy
896 code on X86 processors. It also may be needed by software like
897 XFree86 to initialize some video cards via BIOS. Disabling this
898 option saves about 6k.
899
900config TOSHIBA
901 tristate "Toshiba Laptop support"
902 depends on X86_32
903 ---help---
904 This adds a driver to safely access the System Management Mode of
905 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
906 not work on models with a Phoenix BIOS. The System Management Mode
907 is used to set the BIOS and power saving options on Toshiba portables.
908
909 For information on utilities to make use of this driver see the
910 Toshiba Linux utilities web site at:
911 <http://www.buzzard.org.uk/toshiba/>.
912
913 Say Y if you intend to run this kernel on a Toshiba portable.
914 Say N otherwise.
915
916config I8K
917 tristate "Dell laptop support"
918 select HWMON
919 ---help---
920 This adds a driver to safely access the System Management Mode
921 of the CPU on the Dell Inspiron 8000. The System Management Mode
922 is used to read cpu temperature and cooling fan status and to
923 control the fans on the I8K portables.
924
925 This driver has been tested only on the Inspiron 8000 but it may
926 also work with other Dell laptops. You can force loading on other
927 models by passing the parameter `force=1' to the module. Use at
928 your own risk.
929
930 For information on utilities to make use of this driver see the
931 I8K Linux utilities web site at:
932 <http://people.debian.org/~dz/i8k/>
933
934 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
935 Say N otherwise.
936
937config X86_REBOOTFIXUPS
938 bool "Enable X86 board specific fixups for reboot"
939 depends on X86_32
940 ---help---
941 This enables chipset and/or board specific fixups to be done
942 in order to get reboot to work correctly. This is only needed on
943 some combinations of hardware and BIOS. The symptom, for which
944 this config is intended, is when reboot ends with a stalled/hung
945 system.
946
947 Currently, the only fixup is for the Geode machines using
948 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
949
950 Say Y if you want to enable the fixup. Currently, it's safe to
951 enable this option even if you don't need it.
952 Say N otherwise.
953
954config MICROCODE
955 tristate "/dev/cpu/microcode - microcode support"
956 select FW_LOADER
957 ---help---
958 If you say Y here, you will be able to update the microcode on
959 certain Intel and AMD processors. The Intel support is for the
960 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
961 Pentium 4, Xeon etc. The AMD support is for family 0x10 and
962 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
963 You will obviously need the actual microcode binary data itself
964 which is not shipped with the Linux kernel.
965
966 This option selects the general module only, you need to select
967 at least one vendor specific module as well.
968
969 To compile this driver as a module, choose M here: the
970 module will be called microcode.
971
972config MICROCODE_INTEL
973 bool "Intel microcode patch loading support"
974 depends on MICROCODE
975 default MICROCODE
976 select FW_LOADER
977 ---help---
978 This options enables microcode patch loading support for Intel
979 processors.
980
981 For latest news and information on obtaining all the required
982 Intel ingredients for this driver, check:
983 <http://www.urbanmyth.org/microcode/>.
984
985config MICROCODE_AMD
986 bool "AMD microcode patch loading support"
987 depends on MICROCODE
988 select FW_LOADER
989 ---help---
990 If you select this option, microcode patch loading support for AMD
991 processors will be enabled.
992
993config MICROCODE_OLD_INTERFACE
994 def_bool y
995 depends on MICROCODE
996
997config X86_MSR
998 tristate "/dev/cpu/*/msr - Model-specific register support"
999 ---help---
1000 This device gives privileged processes access to the x86
1001 Model-Specific Registers (MSRs). It is a character device with
1002 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1003 MSR accesses are directed to a specific CPU on multi-processor
1004 systems.
1005
1006config X86_CPUID
1007 tristate "/dev/cpu/*/cpuid - CPU information support"
1008 ---help---
1009 This device gives processes access to the x86 CPUID instruction to
1010 be executed on a specific processor. It is a character device
1011 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1012 /dev/cpu/31/cpuid.
1013
1014choice
1015 prompt "High Memory Support"
1016 default HIGHMEM64G if X86_NUMAQ
1017 default HIGHMEM4G
1018 depends on X86_32
1019
1020config NOHIGHMEM
1021 bool "off"
1022 depends on !X86_NUMAQ
1023 ---help---
1024 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1025 However, the address space of 32-bit x86 processors is only 4
1026 Gigabytes large. That means that, if you have a large amount of
1027 physical memory, not all of it can be "permanently mapped" by the
1028 kernel. The physical memory that's not permanently mapped is called
1029 "high memory".
1030
1031 If you are compiling a kernel which will never run on a machine with
1032 more than 1 Gigabyte total physical RAM, answer "off" here (default
1033 choice and suitable for most users). This will result in a "3GB/1GB"
1034 split: 3GB are mapped so that each process sees a 3GB virtual memory
1035 space and the remaining part of the 4GB virtual memory space is used
1036 by the kernel to permanently map as much physical memory as
1037 possible.
1038
1039 If the machine has between 1 and 4 Gigabytes physical RAM, then
1040 answer "4GB" here.
1041
1042 If more than 4 Gigabytes is used then answer "64GB" here. This
1043 selection turns Intel PAE (Physical Address Extension) mode on.
1044 PAE implements 3-level paging on IA32 processors. PAE is fully
1045 supported by Linux, PAE mode is implemented on all recent Intel
1046 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1047 then the kernel will not boot on CPUs that don't support PAE!
1048
1049 The actual amount of total physical memory will either be
1050 auto detected or can be forced by using a kernel command line option
1051 such as "mem=256M". (Try "man bootparam" or see the documentation of
1052 your boot loader (lilo or loadlin) about how to pass options to the
1053 kernel at boot time.)
1054
1055 If unsure, say "off".
1056
1057config HIGHMEM4G
1058 bool "4GB"
1059 depends on !X86_NUMAQ
1060 ---help---
1061 Select this if you have a 32-bit processor and between 1 and 4
1062 gigabytes of physical RAM.
1063
1064config HIGHMEM64G
1065 bool "64GB"
1066 depends on !M386 && !M486
1067 select X86_PAE
1068 ---help---
1069 Select this if you have a 32-bit processor and more than 4
1070 gigabytes of physical RAM.
1071
1072endchoice
1073
1074choice
1075 depends on EXPERIMENTAL
1076 prompt "Memory split" if EXPERT
1077 default VMSPLIT_3G
1078 depends on X86_32
1079 ---help---
1080 Select the desired split between kernel and user memory.
1081
1082 If the address range available to the kernel is less than the
1083 physical memory installed, the remaining memory will be available
1084 as "high memory". Accessing high memory is a little more costly
1085 than low memory, as it needs to be mapped into the kernel first.
1086 Note that increasing the kernel address space limits the range
1087 available to user programs, making the address space there
1088 tighter. Selecting anything other than the default 3G/1G split
1089 will also likely make your kernel incompatible with binary-only
1090 kernel modules.
1091
1092 If you are not absolutely sure what you are doing, leave this
1093 option alone!
1094
1095 config VMSPLIT_3G
1096 bool "3G/1G user/kernel split"
1097 config VMSPLIT_3G_OPT
1098 depends on !X86_PAE
1099 bool "3G/1G user/kernel split (for full 1G low memory)"
1100 config VMSPLIT_2G
1101 bool "2G/2G user/kernel split"
1102 config VMSPLIT_2G_OPT
1103 depends on !X86_PAE
1104 bool "2G/2G user/kernel split (for full 2G low memory)"
1105 config VMSPLIT_1G
1106 bool "1G/3G user/kernel split"
1107endchoice
1108
1109config PAGE_OFFSET
1110 hex
1111 default 0xB0000000 if VMSPLIT_3G_OPT
1112 default 0x80000000 if VMSPLIT_2G
1113 default 0x78000000 if VMSPLIT_2G_OPT
1114 default 0x40000000 if VMSPLIT_1G
1115 default 0xC0000000
1116 depends on X86_32
1117
1118config HIGHMEM
1119 def_bool y
1120 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1121
1122config X86_PAE
1123 bool "PAE (Physical Address Extension) Support"
1124 depends on X86_32 && !HIGHMEM4G
1125 ---help---
1126 PAE is required for NX support, and furthermore enables
1127 larger swapspace support for non-overcommit purposes. It
1128 has the cost of more pagetable lookup overhead, and also
1129 consumes more pagetable space per process.
1130
1131config ARCH_PHYS_ADDR_T_64BIT
1132 def_bool X86_64 || X86_PAE
1133
1134config ARCH_DMA_ADDR_T_64BIT
1135 def_bool X86_64 || HIGHMEM64G
1136
1137config DIRECT_GBPAGES
1138 bool "Enable 1GB pages for kernel pagetables" if EXPERT
1139 default y
1140 depends on X86_64
1141 ---help---
1142 Allow the kernel linear mapping to use 1GB pages on CPUs that
1143 support it. This can improve the kernel's performance a tiny bit by
1144 reducing TLB pressure. If in doubt, say "Y".
1145
1146# Common NUMA Features
1147config NUMA
1148 bool "Numa Memory Allocation and Scheduler Support"
1149 depends on SMP
1150 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1151 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1152 ---help---
1153 Enable NUMA (Non Uniform Memory Access) support.
1154
1155 The kernel will try to allocate memory used by a CPU on the
1156 local memory controller of the CPU and add some more
1157 NUMA awareness to the kernel.
1158
1159 For 64-bit this is recommended if the system is Intel Core i7
1160 (or later), AMD Opteron, or EM64T NUMA.
1161
1162 For 32-bit this is only needed on (rare) 32-bit-only platforms
1163 that support NUMA topologies, such as NUMAQ / Summit, or if you
1164 boot a 32-bit kernel on a 64-bit NUMA platform.
1165
1166 Otherwise, you should say N.
1167
1168comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1169 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1170
1171config AMD_NUMA
1172 def_bool y
1173 prompt "Old style AMD Opteron NUMA detection"
1174 depends on X86_64 && NUMA && PCI
1175 ---help---
1176 Enable AMD NUMA node topology detection. You should say Y here if
1177 you have a multi processor AMD system. This uses an old method to
1178 read the NUMA configuration directly from the builtin Northbridge
1179 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1180 which also takes priority if both are compiled in.
1181
1182config X86_64_ACPI_NUMA
1183 def_bool y
1184 prompt "ACPI NUMA detection"
1185 depends on X86_64 && NUMA && ACPI && PCI
1186 select ACPI_NUMA
1187 ---help---
1188 Enable ACPI SRAT based node topology detection.
1189
1190# Some NUMA nodes have memory ranges that span
1191# other nodes. Even though a pfn is valid and
1192# between a node's start and end pfns, it may not
1193# reside on that node. See memmap_init_zone()
1194# for details.
1195config NODES_SPAN_OTHER_NODES
1196 def_bool y
1197 depends on X86_64_ACPI_NUMA
1198
1199config NUMA_EMU
1200 bool "NUMA emulation"
1201 depends on NUMA
1202 ---help---
1203 Enable NUMA emulation. A flat machine will be split
1204 into virtual nodes when booted with "numa=fake=N", where N is the
1205 number of nodes. This is only useful for debugging.
1206
1207config NODES_SHIFT
1208 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1209 range 1 10
1210 default "10" if MAXSMP
1211 default "6" if X86_64
1212 default "4" if X86_NUMAQ
1213 default "3"
1214 depends on NEED_MULTIPLE_NODES
1215 ---help---
1216 Specify the maximum number of NUMA Nodes available on the target
1217 system. Increases memory reserved to accommodate various tables.
1218
1219config HAVE_ARCH_BOOTMEM
1220 def_bool y
1221 depends on X86_32 && NUMA
1222
1223config HAVE_ARCH_ALLOC_REMAP
1224 def_bool y
1225 depends on X86_32 && NUMA
1226
1227config ARCH_HAVE_MEMORY_PRESENT
1228 def_bool y
1229 depends on X86_32 && DISCONTIGMEM
1230
1231config NEED_NODE_MEMMAP_SIZE
1232 def_bool y
1233 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1234
1235config ARCH_FLATMEM_ENABLE
1236 def_bool y
1237 depends on X86_32 && !NUMA
1238
1239config ARCH_DISCONTIGMEM_ENABLE
1240 def_bool y
1241 depends on NUMA && X86_32
1242
1243config ARCH_DISCONTIGMEM_DEFAULT
1244 def_bool y
1245 depends on NUMA && X86_32
1246
1247config ARCH_SPARSEMEM_ENABLE
1248 def_bool y
1249 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1250 select SPARSEMEM_STATIC if X86_32
1251 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1252
1253config ARCH_SPARSEMEM_DEFAULT
1254 def_bool y
1255 depends on X86_64
1256
1257config ARCH_SELECT_MEMORY_MODEL
1258 def_bool y
1259 depends on ARCH_SPARSEMEM_ENABLE
1260
1261config ARCH_MEMORY_PROBE
1262 def_bool X86_64
1263 depends on MEMORY_HOTPLUG
1264
1265config ARCH_PROC_KCORE_TEXT
1266 def_bool y
1267 depends on X86_64 && PROC_KCORE
1268
1269config ILLEGAL_POINTER_VALUE
1270 hex
1271 default 0 if X86_32
1272 default 0xdead000000000000 if X86_64
1273
1274source "mm/Kconfig"
1275
1276config HIGHPTE
1277 bool "Allocate 3rd-level pagetables from highmem"
1278 depends on HIGHMEM
1279 ---help---
1280 The VM uses one page table entry for each page of physical memory.
1281 For systems with a lot of RAM, this can be wasteful of precious
1282 low memory. Setting this option will put user-space page table
1283 entries in high memory.
1284
1285config X86_CHECK_BIOS_CORRUPTION
1286 bool "Check for low memory corruption"
1287 ---help---
1288 Periodically check for memory corruption in low memory, which
1289 is suspected to be caused by BIOS. Even when enabled in the
1290 configuration, it is disabled at runtime. Enable it by
1291 setting "memory_corruption_check=1" on the kernel command
1292 line. By default it scans the low 64k of memory every 60
1293 seconds; see the memory_corruption_check_size and
1294 memory_corruption_check_period parameters in
1295 Documentation/kernel-parameters.txt to adjust this.
1296
1297 When enabled with the default parameters, this option has
1298 almost no overhead, as it reserves a relatively small amount
1299 of memory and scans it infrequently. It both detects corruption
1300 and prevents it from affecting the running system.
1301
1302 It is, however, intended as a diagnostic tool; if repeatable
1303 BIOS-originated corruption always affects the same memory,
1304 you can use memmap= to prevent the kernel from using that
1305 memory.
1306
1307config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1308 bool "Set the default setting of memory_corruption_check"
1309 depends on X86_CHECK_BIOS_CORRUPTION
1310 default y
1311 ---help---
1312 Set whether the default state of memory_corruption_check is
1313 on or off.
1314
1315config X86_RESERVE_LOW
1316 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1317 default 64
1318 range 4 640
1319 ---help---
1320 Specify the amount of low memory to reserve for the BIOS.
1321
1322 The first page contains BIOS data structures that the kernel
1323 must not use, so that page must always be reserved.
1324
1325 By default we reserve the first 64K of physical RAM, as a
1326 number of BIOSes are known to corrupt that memory range
1327 during events such as suspend/resume or monitor cable
1328 insertion, so it must not be used by the kernel.
1329
1330 You can set this to 4 if you are absolutely sure that you
1331 trust the BIOS to get all its memory reservations and usages
1332 right. If you know your BIOS have problems beyond the
1333 default 64K area, you can set this to 640 to avoid using the
1334 entire low memory range.
1335
1336 If you have doubts about the BIOS (e.g. suspend/resume does
1337 not work or there's kernel crashes after certain hardware
1338 hotplug events) then you might want to enable
1339 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1340 typical corruption patterns.
1341
1342 Leave this to the default value of 64 if you are unsure.
1343
1344config MATH_EMULATION
1345 bool
1346 prompt "Math emulation" if X86_32
1347 ---help---
1348 Linux can emulate a math coprocessor (used for floating point
1349 operations) if you don't have one. 486DX and Pentium processors have
1350 a math coprocessor built in, 486SX and 386 do not, unless you added
1351 a 487DX or 387, respectively. (The messages during boot time can
1352 give you some hints here ["man dmesg"].) Everyone needs either a
1353 coprocessor or this emulation.
1354
1355 If you don't have a math coprocessor, you need to say Y here; if you
1356 say Y here even though you have a coprocessor, the coprocessor will
1357 be used nevertheless. (This behavior can be changed with the kernel
1358 command line option "no387", which comes handy if your coprocessor
1359 is broken. Try "man bootparam" or see the documentation of your boot
1360 loader (lilo or loadlin) about how to pass options to the kernel at
1361 boot time.) This means that it is a good idea to say Y here if you
1362 intend to use this kernel on different machines.
1363
1364 More information about the internals of the Linux math coprocessor
1365 emulation can be found in <file:arch/x86/math-emu/README>.
1366
1367 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1368 kernel, it won't hurt.
1369
1370config MTRR
1371 def_bool y
1372 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1373 ---help---
1374 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1375 the Memory Type Range Registers (MTRRs) may be used to control
1376 processor access to memory ranges. This is most useful if you have
1377 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1378 allows bus write transfers to be combined into a larger transfer
1379 before bursting over the PCI/AGP bus. This can increase performance
1380 of image write operations 2.5 times or more. Saying Y here creates a
1381 /proc/mtrr file which may be used to manipulate your processor's
1382 MTRRs. Typically the X server should use this.
1383
1384 This code has a reasonably generic interface so that similar
1385 control registers on other processors can be easily supported
1386 as well:
1387
1388 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1389 Registers (ARRs) which provide a similar functionality to MTRRs. For
1390 these, the ARRs are used to emulate the MTRRs.
1391 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1392 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1393 write-combining. All of these processors are supported by this code
1394 and it makes sense to say Y here if you have one of them.
1395
1396 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1397 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1398 can lead to all sorts of problems, so it's good to say Y here.
1399
1400 You can safely say Y even if your machine doesn't have MTRRs, you'll
1401 just add about 9 KB to your kernel.
1402
1403 See <file:Documentation/x86/mtrr.txt> for more information.
1404
1405config MTRR_SANITIZER
1406 def_bool y
1407 prompt "MTRR cleanup support"
1408 depends on MTRR
1409 ---help---
1410 Convert MTRR layout from continuous to discrete, so X drivers can
1411 add writeback entries.
1412
1413 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1414 The largest mtrr entry size for a continuous block can be set with
1415 mtrr_chunk_size.
1416
1417 If unsure, say Y.
1418
1419config MTRR_SANITIZER_ENABLE_DEFAULT
1420 int "MTRR cleanup enable value (0-1)"
1421 range 0 1
1422 default "0"
1423 depends on MTRR_SANITIZER
1424 ---help---
1425 Enable mtrr cleanup default value
1426
1427config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1428 int "MTRR cleanup spare reg num (0-7)"
1429 range 0 7
1430 default "1"
1431 depends on MTRR_SANITIZER
1432 ---help---
1433 mtrr cleanup spare entries default, it can be changed via
1434 mtrr_spare_reg_nr=N on the kernel command line.
1435
1436config X86_PAT
1437 def_bool y
1438 prompt "x86 PAT support" if EXPERT
1439 depends on MTRR
1440 ---help---
1441 Use PAT attributes to setup page level cache control.
1442
1443 PATs are the modern equivalents of MTRRs and are much more
1444 flexible than MTRRs.
1445
1446 Say N here if you see bootup problems (boot crash, boot hang,
1447 spontaneous reboots) or a non-working video driver.
1448
1449 If unsure, say Y.
1450
1451config ARCH_USES_PG_UNCACHED
1452 def_bool y
1453 depends on X86_PAT
1454
1455config EFI
1456 bool "EFI runtime service support"
1457 depends on ACPI
1458 ---help---
1459 This enables the kernel to use EFI runtime services that are
1460 available (such as the EFI variable services).
1461
1462 This option is only useful on systems that have EFI firmware.
1463 In addition, you should use the latest ELILO loader available
1464 at <http://elilo.sourceforge.net> in order to take advantage
1465 of EFI runtime services. However, even with this option, the
1466 resultant kernel should continue to boot on existing non-EFI
1467 platforms.
1468
1469config SECCOMP
1470 def_bool y
1471 prompt "Enable seccomp to safely compute untrusted bytecode"
1472 ---help---
1473 This kernel feature is useful for number crunching applications
1474 that may need to compute untrusted bytecode during their
1475 execution. By using pipes or other transports made available to
1476 the process as file descriptors supporting the read/write
1477 syscalls, it's possible to isolate those applications in
1478 their own address space using seccomp. Once seccomp is
1479 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1480 and the task is only allowed to execute a few safe syscalls
1481 defined by each seccomp mode.
1482
1483 If unsure, say Y. Only embedded should say N here.
1484
1485config CC_STACKPROTECTOR
1486 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1487 ---help---
1488 This option turns on the -fstack-protector GCC feature. This
1489 feature puts, at the beginning of functions, a canary value on
1490 the stack just before the return address, and validates
1491 the value just before actually returning. Stack based buffer
1492 overflows (that need to overwrite this return address) now also
1493 overwrite the canary, which gets detected and the attack is then
1494 neutralized via a kernel panic.
1495
1496 This feature requires gcc version 4.2 or above, or a distribution
1497 gcc with the feature backported. Older versions are automatically
1498 detected and for those versions, this configuration option is
1499 ignored. (and a warning is printed during bootup)
1500
1501source kernel/Kconfig.hz
1502
1503config KEXEC
1504 bool "kexec system call"
1505 ---help---
1506 kexec is a system call that implements the ability to shutdown your
1507 current kernel, and to start another kernel. It is like a reboot
1508 but it is independent of the system firmware. And like a reboot
1509 you can start any kernel with it, not just Linux.
1510
1511 The name comes from the similarity to the exec system call.
1512
1513 It is an ongoing process to be certain the hardware in a machine
1514 is properly shutdown, so do not be surprised if this code does not
1515 initially work for you. It may help to enable device hotplugging
1516 support. As of this writing the exact hardware interface is
1517 strongly in flux, so no good recommendation can be made.
1518
1519config CRASH_DUMP
1520 bool "kernel crash dumps"
1521 depends on X86_64 || (X86_32 && HIGHMEM)
1522 ---help---
1523 Generate crash dump after being started by kexec.
1524 This should be normally only set in special crash dump kernels
1525 which are loaded in the main kernel with kexec-tools into
1526 a specially reserved region and then later executed after
1527 a crash by kdump/kexec. The crash dump kernel must be compiled
1528 to a memory address not used by the main kernel or BIOS using
1529 PHYSICAL_START, or it must be built as a relocatable image
1530 (CONFIG_RELOCATABLE=y).
1531 For more details see Documentation/kdump/kdump.txt
1532
1533config KEXEC_JUMP
1534 bool "kexec jump (EXPERIMENTAL)"
1535 depends on EXPERIMENTAL
1536 depends on KEXEC && HIBERNATION
1537 ---help---
1538 Jump between original kernel and kexeced kernel and invoke
1539 code in physical address mode via KEXEC
1540
1541config PHYSICAL_START
1542 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1543 default "0x1000000"
1544 ---help---
1545 This gives the physical address where the kernel is loaded.
1546
1547 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1548 bzImage will decompress itself to above physical address and
1549 run from there. Otherwise, bzImage will run from the address where
1550 it has been loaded by the boot loader and will ignore above physical
1551 address.
1552
1553 In normal kdump cases one does not have to set/change this option
1554 as now bzImage can be compiled as a completely relocatable image
1555 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1556 address. This option is mainly useful for the folks who don't want
1557 to use a bzImage for capturing the crash dump and want to use a
1558 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1559 to be specifically compiled to run from a specific memory area
1560 (normally a reserved region) and this option comes handy.
1561
1562 So if you are using bzImage for capturing the crash dump,
1563 leave the value here unchanged to 0x1000000 and set
1564 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1565 for capturing the crash dump change this value to start of
1566 the reserved region. In other words, it can be set based on
1567 the "X" value as specified in the "crashkernel=YM@XM"
1568 command line boot parameter passed to the panic-ed
1569 kernel. Please take a look at Documentation/kdump/kdump.txt
1570 for more details about crash dumps.
1571
1572 Usage of bzImage for capturing the crash dump is recommended as
1573 one does not have to build two kernels. Same kernel can be used
1574 as production kernel and capture kernel. Above option should have
1575 gone away after relocatable bzImage support is introduced. But it
1576 is present because there are users out there who continue to use
1577 vmlinux for dump capture. This option should go away down the
1578 line.
1579
1580 Don't change this unless you know what you are doing.
1581
1582config RELOCATABLE
1583 bool "Build a relocatable kernel"
1584 default y
1585 ---help---
1586 This builds a kernel image that retains relocation information
1587 so it can be loaded someplace besides the default 1MB.
1588 The relocations tend to make the kernel binary about 10% larger,
1589 but are discarded at runtime.
1590
1591 One use is for the kexec on panic case where the recovery kernel
1592 must live at a different physical address than the primary
1593 kernel.
1594
1595 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1596 it has been loaded at and the compile time physical address
1597 (CONFIG_PHYSICAL_START) is ignored.
1598
1599# Relocation on x86-32 needs some additional build support
1600config X86_NEED_RELOCS
1601 def_bool y
1602 depends on X86_32 && RELOCATABLE
1603
1604config PHYSICAL_ALIGN
1605 hex "Alignment value to which kernel should be aligned" if X86_32
1606 default "0x1000000"
1607 range 0x2000 0x1000000
1608 ---help---
1609 This value puts the alignment restrictions on physical address
1610 where kernel is loaded and run from. Kernel is compiled for an
1611 address which meets above alignment restriction.
1612
1613 If bootloader loads the kernel at a non-aligned address and
1614 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1615 address aligned to above value and run from there.
1616
1617 If bootloader loads the kernel at a non-aligned address and
1618 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1619 load address and decompress itself to the address it has been
1620 compiled for and run from there. The address for which kernel is
1621 compiled already meets above alignment restrictions. Hence the
1622 end result is that kernel runs from a physical address meeting
1623 above alignment restrictions.
1624
1625 Don't change this unless you know what you are doing.
1626
1627config HOTPLUG_CPU
1628 bool "Support for hot-pluggable CPUs"
1629 depends on SMP && HOTPLUG
1630 ---help---
1631 Say Y here to allow turning CPUs off and on. CPUs can be
1632 controlled through /sys/devices/system/cpu.
1633 ( Note: power management support will enable this option
1634 automatically on SMP systems. )
1635 Say N if you want to disable CPU hotplug.
1636
1637config COMPAT_VDSO
1638 def_bool y
1639 prompt "Compat VDSO support"
1640 depends on X86_32 || IA32_EMULATION
1641 ---help---
1642 Map the 32-bit VDSO to the predictable old-style address too.
1643
1644 Say N here if you are running a sufficiently recent glibc
1645 version (2.3.3 or later), to remove the high-mapped
1646 VDSO mapping and to exclusively use the randomized VDSO.
1647
1648 If unsure, say Y.
1649
1650config CMDLINE_BOOL
1651 bool "Built-in kernel command line"
1652 ---help---
1653 Allow for specifying boot arguments to the kernel at
1654 build time. On some systems (e.g. embedded ones), it is
1655 necessary or convenient to provide some or all of the
1656 kernel boot arguments with the kernel itself (that is,
1657 to not rely on the boot loader to provide them.)
1658
1659 To compile command line arguments into the kernel,
1660 set this option to 'Y', then fill in the
1661 the boot arguments in CONFIG_CMDLINE.
1662
1663 Systems with fully functional boot loaders (i.e. non-embedded)
1664 should leave this option set to 'N'.
1665
1666config CMDLINE
1667 string "Built-in kernel command string"
1668 depends on CMDLINE_BOOL
1669 default ""
1670 ---help---
1671 Enter arguments here that should be compiled into the kernel
1672 image and used at boot time. If the boot loader provides a
1673 command line at boot time, it is appended to this string to
1674 form the full kernel command line, when the system boots.
1675
1676 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1677 change this behavior.
1678
1679 In most cases, the command line (whether built-in or provided
1680 by the boot loader) should specify the device for the root
1681 file system.
1682
1683config CMDLINE_OVERRIDE
1684 bool "Built-in command line overrides boot loader arguments"
1685 depends on CMDLINE_BOOL
1686 ---help---
1687 Set this option to 'Y' to have the kernel ignore the boot loader
1688 command line, and use ONLY the built-in command line.
1689
1690 This is used to work around broken boot loaders. This should
1691 be set to 'N' under normal conditions.
1692
1693endmenu
1694
1695config ARCH_ENABLE_MEMORY_HOTPLUG
1696 def_bool y
1697 depends on X86_64 || (X86_32 && HIGHMEM)
1698
1699config ARCH_ENABLE_MEMORY_HOTREMOVE
1700 def_bool y
1701 depends on MEMORY_HOTPLUG
1702
1703config USE_PERCPU_NUMA_NODE_ID
1704 def_bool y
1705 depends on NUMA
1706
1707menu "Power management and ACPI options"
1708
1709config ARCH_HIBERNATION_HEADER
1710 def_bool y
1711 depends on X86_64 && HIBERNATION
1712
1713source "kernel/power/Kconfig"
1714
1715source "drivers/acpi/Kconfig"
1716
1717source "drivers/sfi/Kconfig"
1718
1719config X86_APM_BOOT
1720 def_bool y
1721 depends on APM || APM_MODULE
1722
1723menuconfig APM
1724 tristate "APM (Advanced Power Management) BIOS support"
1725 depends on X86_32 && PM_SLEEP
1726 ---help---
1727 APM is a BIOS specification for saving power using several different
1728 techniques. This is mostly useful for battery powered laptops with
1729 APM compliant BIOSes. If you say Y here, the system time will be
1730 reset after a RESUME operation, the /proc/apm device will provide
1731 battery status information, and user-space programs will receive
1732 notification of APM "events" (e.g. battery status change).
1733
1734 If you select "Y" here, you can disable actual use of the APM
1735 BIOS by passing the "apm=off" option to the kernel at boot time.
1736
1737 Note that the APM support is almost completely disabled for
1738 machines with more than one CPU.
1739
1740 In order to use APM, you will need supporting software. For location
1741 and more information, read <file:Documentation/power/apm-acpi.txt>
1742 and the Battery Powered Linux mini-HOWTO, available from
1743 <http://www.tldp.org/docs.html#howto>.
1744
1745 This driver does not spin down disk drives (see the hdparm(8)
1746 manpage ("man 8 hdparm") for that), and it doesn't turn off
1747 VESA-compliant "green" monitors.
1748
1749 This driver does not support the TI 4000M TravelMate and the ACER
1750 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1751 desktop machines also don't have compliant BIOSes, and this driver
1752 may cause those machines to panic during the boot phase.
1753
1754 Generally, if you don't have a battery in your machine, there isn't
1755 much point in using this driver and you should say N. If you get
1756 random kernel OOPSes or reboots that don't seem to be related to
1757 anything, try disabling/enabling this option (or disabling/enabling
1758 APM in your BIOS).
1759
1760 Some other things you should try when experiencing seemingly random,
1761 "weird" problems:
1762
1763 1) make sure that you have enough swap space and that it is
1764 enabled.
1765 2) pass the "no-hlt" option to the kernel
1766 3) switch on floating point emulation in the kernel and pass
1767 the "no387" option to the kernel
1768 4) pass the "floppy=nodma" option to the kernel
1769 5) pass the "mem=4M" option to the kernel (thereby disabling
1770 all but the first 4 MB of RAM)
1771 6) make sure that the CPU is not over clocked.
1772 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1773 8) disable the cache from your BIOS settings
1774 9) install a fan for the video card or exchange video RAM
1775 10) install a better fan for the CPU
1776 11) exchange RAM chips
1777 12) exchange the motherboard.
1778
1779 To compile this driver as a module, choose M here: the
1780 module will be called apm.
1781
1782if APM
1783
1784config APM_IGNORE_USER_SUSPEND
1785 bool "Ignore USER SUSPEND"
1786 ---help---
1787 This option will ignore USER SUSPEND requests. On machines with a
1788 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1789 series notebooks, it is necessary to say Y because of a BIOS bug.
1790
1791config APM_DO_ENABLE
1792 bool "Enable PM at boot time"
1793 ---help---
1794 Enable APM features at boot time. From page 36 of the APM BIOS
1795 specification: "When disabled, the APM BIOS does not automatically
1796 power manage devices, enter the Standby State, enter the Suspend
1797 State, or take power saving steps in response to CPU Idle calls."
1798 This driver will make CPU Idle calls when Linux is idle (unless this
1799 feature is turned off -- see "Do CPU IDLE calls", below). This
1800 should always save battery power, but more complicated APM features
1801 will be dependent on your BIOS implementation. You may need to turn
1802 this option off if your computer hangs at boot time when using APM
1803 support, or if it beeps continuously instead of suspending. Turn
1804 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1805 T400CDT. This is off by default since most machines do fine without
1806 this feature.
1807
1808config APM_CPU_IDLE
1809 bool "Make CPU Idle calls when idle"
1810 ---help---
1811 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1812 On some machines, this can activate improved power savings, such as
1813 a slowed CPU clock rate, when the machine is idle. These idle calls
1814 are made after the idle loop has run for some length of time (e.g.,
1815 333 mS). On some machines, this will cause a hang at boot time or
1816 whenever the CPU becomes idle. (On machines with more than one CPU,
1817 this option does nothing.)
1818
1819config APM_DISPLAY_BLANK
1820 bool "Enable console blanking using APM"
1821 ---help---
1822 Enable console blanking using the APM. Some laptops can use this to
1823 turn off the LCD backlight when the screen blanker of the Linux
1824 virtual console blanks the screen. Note that this is only used by
1825 the virtual console screen blanker, and won't turn off the backlight
1826 when using the X Window system. This also doesn't have anything to
1827 do with your VESA-compliant power-saving monitor. Further, this
1828 option doesn't work for all laptops -- it might not turn off your
1829 backlight at all, or it might print a lot of errors to the console,
1830 especially if you are using gpm.
1831
1832config APM_ALLOW_INTS
1833 bool "Allow interrupts during APM BIOS calls"
1834 ---help---
1835 Normally we disable external interrupts while we are making calls to
1836 the APM BIOS as a measure to lessen the effects of a badly behaving
1837 BIOS implementation. The BIOS should reenable interrupts if it
1838 needs to. Unfortunately, some BIOSes do not -- especially those in
1839 many of the newer IBM Thinkpads. If you experience hangs when you
1840 suspend, try setting this to Y. Otherwise, say N.
1841
1842endif # APM
1843
1844source "drivers/cpufreq/Kconfig"
1845
1846source "drivers/cpuidle/Kconfig"
1847
1848source "drivers/idle/Kconfig"
1849
1850endmenu
1851
1852
1853menu "Bus options (PCI etc.)"
1854
1855config PCI
1856 bool "PCI support"
1857 default y
1858 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1859 ---help---
1860 Find out whether you have a PCI motherboard. PCI is the name of a
1861 bus system, i.e. the way the CPU talks to the other stuff inside
1862 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1863 VESA. If you have PCI, say Y, otherwise N.
1864
1865choice
1866 prompt "PCI access mode"
1867 depends on X86_32 && PCI
1868 default PCI_GOANY
1869 ---help---
1870 On PCI systems, the BIOS can be used to detect the PCI devices and
1871 determine their configuration. However, some old PCI motherboards
1872 have BIOS bugs and may crash if this is done. Also, some embedded
1873 PCI-based systems don't have any BIOS at all. Linux can also try to
1874 detect the PCI hardware directly without using the BIOS.
1875
1876 With this option, you can specify how Linux should detect the
1877 PCI devices. If you choose "BIOS", the BIOS will be used,
1878 if you choose "Direct", the BIOS won't be used, and if you
1879 choose "MMConfig", then PCI Express MMCONFIG will be used.
1880 If you choose "Any", the kernel will try MMCONFIG, then the
1881 direct access method and falls back to the BIOS if that doesn't
1882 work. If unsure, go with the default, which is "Any".
1883
1884config PCI_GOBIOS
1885 bool "BIOS"
1886
1887config PCI_GOMMCONFIG
1888 bool "MMConfig"
1889
1890config PCI_GODIRECT
1891 bool "Direct"
1892
1893config PCI_GOOLPC
1894 bool "OLPC XO-1"
1895 depends on OLPC
1896
1897config PCI_GOANY
1898 bool "Any"
1899
1900endchoice
1901
1902config PCI_BIOS
1903 def_bool y
1904 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1905
1906# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1907config PCI_DIRECT
1908 def_bool y
1909 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
1910
1911config PCI_MMCONFIG
1912 def_bool y
1913 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
1914
1915config PCI_OLPC
1916 def_bool y
1917 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1918
1919config PCI_XEN
1920 def_bool y
1921 depends on PCI && XEN
1922 select SWIOTLB_XEN
1923
1924config PCI_DOMAINS
1925 def_bool y
1926 depends on PCI
1927
1928config PCI_MMCONFIG
1929 bool "Support mmconfig PCI config space access"
1930 depends on X86_64 && PCI && ACPI
1931
1932config PCI_CNB20LE_QUIRK
1933 bool "Read CNB20LE Host Bridge Windows" if EXPERT
1934 default n
1935 depends on PCI && EXPERIMENTAL
1936 help
1937 Read the PCI windows out of the CNB20LE host bridge. This allows
1938 PCI hotplug to work on systems with the CNB20LE chipset which do
1939 not have ACPI.
1940
1941 There's no public spec for this chipset, and this functionality
1942 is known to be incomplete.
1943
1944 You should say N unless you know you need this.
1945
1946source "drivers/pci/pcie/Kconfig"
1947
1948source "drivers/pci/Kconfig"
1949
1950# x86_64 have no ISA slots, but can have ISA-style DMA.
1951config ISA_DMA_API
1952 bool "ISA-style DMA support" if (X86_64 && EXPERT)
1953 default y
1954 help
1955 Enables ISA-style DMA support for devices requiring such controllers.
1956 If unsure, say Y.
1957
1958if X86_32
1959
1960config ISA
1961 bool "ISA support"
1962 ---help---
1963 Find out whether you have ISA slots on your motherboard. ISA is the
1964 name of a bus system, i.e. the way the CPU talks to the other stuff
1965 inside your box. Other bus systems are PCI, EISA, MicroChannel
1966 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1967 newer boards don't support it. If you have ISA, say Y, otherwise N.
1968
1969config EISA
1970 bool "EISA support"
1971 depends on ISA
1972 ---help---
1973 The Extended Industry Standard Architecture (EISA) bus was
1974 developed as an open alternative to the IBM MicroChannel bus.
1975
1976 The EISA bus provided some of the features of the IBM MicroChannel
1977 bus while maintaining backward compatibility with cards made for
1978 the older ISA bus. The EISA bus saw limited use between 1988 and
1979 1995 when it was made obsolete by the PCI bus.
1980
1981 Say Y here if you are building a kernel for an EISA-based machine.
1982
1983 Otherwise, say N.
1984
1985source "drivers/eisa/Kconfig"
1986
1987config MCA
1988 bool "MCA support"
1989 ---help---
1990 MicroChannel Architecture is found in some IBM PS/2 machines and
1991 laptops. It is a bus system similar to PCI or ISA. See
1992 <file:Documentation/mca.txt> (and especially the web page given
1993 there) before attempting to build an MCA bus kernel.
1994
1995source "drivers/mca/Kconfig"
1996
1997config SCx200
1998 tristate "NatSemi SCx200 support"
1999 ---help---
2000 This provides basic support for National Semiconductor's
2001 (now AMD's) Geode processors. The driver probes for the
2002 PCI-IDs of several on-chip devices, so its a good dependency
2003 for other scx200_* drivers.
2004
2005 If compiled as a module, the driver is named scx200.
2006
2007config SCx200HR_TIMER
2008 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2009 depends on SCx200
2010 default y
2011 ---help---
2012 This driver provides a clocksource built upon the on-chip
2013 27MHz high-resolution timer. Its also a workaround for
2014 NSC Geode SC-1100's buggy TSC, which loses time when the
2015 processor goes idle (as is done by the scheduler). The
2016 other workaround is idle=poll boot option.
2017
2018config OLPC
2019 bool "One Laptop Per Child support"
2020 depends on !X86_PAE
2021 select GPIOLIB
2022 select OF
2023 select OF_PROMTREE
2024 ---help---
2025 Add support for detecting the unique features of the OLPC
2026 XO hardware.
2027
2028config OLPC_XO1_PM
2029 bool "OLPC XO-1 Power Management"
2030 depends on OLPC && MFD_CS5535 && PM_SLEEP
2031 select MFD_CORE
2032 ---help---
2033 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2034
2035config OLPC_XO1_RTC
2036 bool "OLPC XO-1 Real Time Clock"
2037 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2038 ---help---
2039 Add support for the XO-1 real time clock, which can be used as a
2040 programmable wakeup source.
2041
2042config OLPC_XO1_SCI
2043 bool "OLPC XO-1 SCI extras"
2044 depends on OLPC && OLPC_XO1_PM
2045 select POWER_SUPPLY
2046 select GPIO_CS5535
2047 select MFD_CORE
2048 ---help---
2049 Add support for SCI-based features of the OLPC XO-1 laptop:
2050 - EC-driven system wakeups
2051 - Power button
2052 - Ebook switch
2053 - Lid switch
2054 - AC adapter status updates
2055 - Battery status updates
2056
2057config OLPC_XO15_SCI
2058 bool "OLPC XO-1.5 SCI extras"
2059 depends on OLPC && ACPI
2060 select POWER_SUPPLY
2061 ---help---
2062 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2063 - EC-driven system wakeups
2064 - AC adapter status updates
2065 - Battery status updates
2066
2067endif # X86_32
2068
2069config AMD_NB
2070 def_bool y
2071 depends on CPU_SUP_AMD && PCI
2072
2073source "drivers/pcmcia/Kconfig"
2074
2075source "drivers/pci/hotplug/Kconfig"
2076
2077config RAPIDIO
2078 bool "RapidIO support"
2079 depends on PCI
2080 default n
2081 help
2082 If you say Y here, the kernel will include drivers and
2083 infrastructure code to support RapidIO interconnect devices.
2084
2085source "drivers/rapidio/Kconfig"
2086
2087endmenu
2088
2089
2090menu "Executable file formats / Emulations"
2091
2092source "fs/Kconfig.binfmt"
2093
2094config IA32_EMULATION
2095 bool "IA32 Emulation"
2096 depends on X86_64
2097 select COMPAT_BINFMT_ELF
2098 ---help---
2099 Include code to run 32-bit programs under a 64-bit kernel. You should
2100 likely turn this on, unless you're 100% sure that you don't have any
2101 32-bit programs left.
2102
2103config IA32_AOUT
2104 tristate "IA32 a.out support"
2105 depends on IA32_EMULATION
2106 ---help---
2107 Support old a.out binaries in the 32bit emulation.
2108
2109config COMPAT
2110 def_bool y
2111 depends on IA32_EMULATION
2112
2113config COMPAT_FOR_U64_ALIGNMENT
2114 def_bool COMPAT
2115 depends on X86_64
2116
2117config SYSVIPC_COMPAT
2118 def_bool y
2119 depends on COMPAT && SYSVIPC
2120
2121config KEYS_COMPAT
2122 bool
2123 depends on COMPAT && KEYS
2124 default y
2125
2126endmenu
2127
2128
2129config HAVE_ATOMIC_IOMAP
2130 def_bool y
2131 depends on X86_32
2132
2133config HAVE_TEXT_POKE_SMP
2134 bool
2135 select STOP_MACHINE if SMP
2136
2137source "net/Kconfig"
2138
2139source "drivers/Kconfig"
2140
2141source "drivers/firmware/Kconfig"
2142
2143source "fs/Kconfig"
2144
2145source "arch/x86/Kconfig.debug"
2146
2147source "security/Kconfig"
2148
2149source "crypto/Kconfig"
2150
2151source "arch/x86/kvm/Kconfig"
2152
2153source "lib/Kconfig"