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