Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel...
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / x86 / Kconfig
1 # Select 32 or 64 bit
2 config 64BIT
3 bool "64-bit kernel" if ARCH = "x86"
4 default ARCH = "x86_64"
5 ---help---
6 Say yes to build a 64-bit kernel - formerly known as x86_64
7 Say no to build a 32-bit kernel - formerly known as i386
8
9 config X86_32
10 def_bool !64BIT
11 select CLKSRC_I8253
12
13 config X86_64
14 def_bool 64BIT
15 select X86_DEV_DMA_OPS
16
17 ### Arch settings
18 config 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_FENTRY if X86_64
40 select HAVE_C_RECORDMCOUNT
41 select HAVE_DYNAMIC_FTRACE
42 select HAVE_FUNCTION_TRACER
43 select HAVE_FUNCTION_GRAPH_TRACER
44 select HAVE_FUNCTION_GRAPH_FP_TEST
45 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
46 select HAVE_SYSCALL_TRACEPOINTS
47 select HAVE_KVM
48 select HAVE_ARCH_KGDB
49 select HAVE_ARCH_TRACEHOOK
50 select HAVE_GENERIC_DMA_COHERENT if X86_32
51 select HAVE_EFFICIENT_UNALIGNED_ACCESS
52 select USER_STACKTRACE_SUPPORT
53 select HAVE_REGS_AND_STACK_ACCESS_API
54 select HAVE_DMA_API_DEBUG
55 select HAVE_KERNEL_GZIP
56 select HAVE_KERNEL_BZIP2
57 select HAVE_KERNEL_LZMA
58 select HAVE_KERNEL_XZ
59 select HAVE_KERNEL_LZO
60 select HAVE_HW_BREAKPOINT
61 select HAVE_MIXED_BREAKPOINTS_REGS
62 select PERF_EVENTS
63 select HAVE_PERF_EVENTS_NMI
64 select HAVE_PERF_REGS
65 select HAVE_PERF_USER_STACK_DUMP
66 select ANON_INODES
67 select HAVE_ALIGNED_STRUCT_PAGE if SLUB && !M386
68 select HAVE_CMPXCHG_LOCAL if !M386
69 select HAVE_CMPXCHG_DOUBLE
70 select HAVE_ARCH_KMEMCHECK
71 select HAVE_USER_RETURN_NOTIFIER
72 select ARCH_BINFMT_ELF_RANDOMIZE_PIE
73 select HAVE_ARCH_JUMP_LABEL
74 select HAVE_TEXT_POKE_SMP
75 select HAVE_GENERIC_HARDIRQS
76 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
77 select SPARSE_IRQ
78 select GENERIC_FIND_FIRST_BIT
79 select GENERIC_IRQ_PROBE
80 select GENERIC_PENDING_IRQ if SMP
81 select GENERIC_IRQ_SHOW
82 select GENERIC_CLOCKEVENTS_MIN_ADJUST
83 select IRQ_FORCED_THREADING
84 select USE_GENERIC_SMP_HELPERS if SMP
85 select HAVE_BPF_JIT if X86_64
86 select CLKEVT_I8253
87 select ARCH_HAVE_NMI_SAFE_CMPXCHG
88 select GENERIC_IOMAP
89 select DCACHE_WORD_ACCESS
90 select GENERIC_SMP_IDLE_THREAD
91 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
92 select HAVE_ARCH_SECCOMP_FILTER
93 select BUILDTIME_EXTABLE_SORT
94 select GENERIC_CMOS_UPDATE
95 select CLOCKSOURCE_WATCHDOG
96 select GENERIC_CLOCKEVENTS
97 select ARCH_CLOCKSOURCE_DATA if X86_64
98 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
99 select GENERIC_TIME_VSYSCALL if X86_64
100 select KTIME_SCALAR if X86_32
101 select GENERIC_STRNCPY_FROM_USER
102 select GENERIC_STRNLEN_USER
103 select HAVE_RCU_USER_QS if X86_64
104 select HAVE_IRQ_TIME_ACCOUNTING
105
106 config INSTRUCTION_DECODER
107 def_bool (KPROBES || PERF_EVENTS || UPROBES)
108
109 config OUTPUT_FORMAT
110 string
111 default "elf32-i386" if X86_32
112 default "elf64-x86-64" if X86_64
113
114 config ARCH_DEFCONFIG
115 string
116 default "arch/x86/configs/i386_defconfig" if X86_32
117 default "arch/x86/configs/x86_64_defconfig" if X86_64
118
119 config LOCKDEP_SUPPORT
120 def_bool y
121
122 config STACKTRACE_SUPPORT
123 def_bool y
124
125 config HAVE_LATENCYTOP_SUPPORT
126 def_bool y
127
128 config MMU
129 def_bool y
130
131 config SBUS
132 bool
133
134 config NEED_DMA_MAP_STATE
135 def_bool (X86_64 || INTEL_IOMMU || DMA_API_DEBUG)
136
137 config NEED_SG_DMA_LENGTH
138 def_bool y
139
140 config GENERIC_ISA_DMA
141 def_bool ISA_DMA_API
142
143 config GENERIC_BUG
144 def_bool y
145 depends on BUG
146 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
147
148 config GENERIC_BUG_RELATIVE_POINTERS
149 bool
150
151 config GENERIC_HWEIGHT
152 def_bool y
153
154 config GENERIC_GPIO
155 bool
156
157 config ARCH_MAY_HAVE_PC_FDC
158 def_bool ISA_DMA_API
159
160 config RWSEM_GENERIC_SPINLOCK
161 def_bool !X86_XADD
162
163 config RWSEM_XCHGADD_ALGORITHM
164 def_bool X86_XADD
165
166 config GENERIC_CALIBRATE_DELAY
167 def_bool y
168
169 config ARCH_HAS_CPU_RELAX
170 def_bool y
171
172 config ARCH_HAS_DEFAULT_IDLE
173 def_bool y
174
175 config ARCH_HAS_CACHE_LINE_SIZE
176 def_bool y
177
178 config ARCH_HAS_CPU_AUTOPROBE
179 def_bool y
180
181 config HAVE_SETUP_PER_CPU_AREA
182 def_bool y
183
184 config NEED_PER_CPU_EMBED_FIRST_CHUNK
185 def_bool y
186
187 config NEED_PER_CPU_PAGE_FIRST_CHUNK
188 def_bool y
189
190 config ARCH_HIBERNATION_POSSIBLE
191 def_bool y
192
193 config ARCH_SUSPEND_POSSIBLE
194 def_bool y
195
196 config ZONE_DMA32
197 bool
198 default X86_64
199
200 config AUDIT_ARCH
201 bool
202 default X86_64
203
204 config ARCH_SUPPORTS_OPTIMIZED_INLINING
205 def_bool y
206
207 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
208 def_bool y
209
210 config HAVE_INTEL_TXT
211 def_bool y
212 depends on EXPERIMENTAL && INTEL_IOMMU && ACPI
213
214 config X86_32_SMP
215 def_bool y
216 depends on X86_32 && SMP
217
218 config X86_64_SMP
219 def_bool y
220 depends on X86_64 && SMP
221
222 config X86_HT
223 def_bool y
224 depends on SMP
225
226 config X86_32_LAZY_GS
227 def_bool y
228 depends on X86_32 && !CC_STACKPROTECTOR
229
230 config ARCH_HWEIGHT_CFLAGS
231 string
232 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
233 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
234
235 config ARCH_CPU_PROBE_RELEASE
236 def_bool y
237 depends on HOTPLUG_CPU
238
239 config ARCH_SUPPORTS_UPROBES
240 def_bool y
241
242 source "init/Kconfig"
243 source "kernel/Kconfig.freezer"
244
245 menu "Processor type and features"
246
247 config ZONE_DMA
248 bool "DMA memory allocation support" if EXPERT
249 default y
250 help
251 DMA memory allocation support allows devices with less than 32-bit
252 addressing to allocate within the first 16MB of address space.
253 Disable if no such devices will be used.
254
255 If unsure, say Y.
256
257 config SMP
258 bool "Symmetric multi-processing support"
259 ---help---
260 This enables support for systems with more than one CPU. If you have
261 a system with only one CPU, like most personal computers, say N. If
262 you have a system with more than one CPU, say Y.
263
264 If you say N here, the kernel will run on single and multiprocessor
265 machines, but will use only one CPU of a multiprocessor machine. If
266 you say Y here, the kernel will run on many, but not all,
267 singleprocessor machines. On a singleprocessor machine, the kernel
268 will run faster if you say N here.
269
270 Note that if you say Y here and choose architecture "586" or
271 "Pentium" under "Processor family", the kernel will not work on 486
272 architectures. Similarly, multiprocessor kernels for the "PPro"
273 architecture may not work on all Pentium based boards.
274
275 People using multiprocessor machines who say Y here should also say
276 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
277 Management" code will be disabled if you say Y here.
278
279 See also <file:Documentation/x86/i386/IO-APIC.txt>,
280 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
281 <http://www.tldp.org/docs.html#howto>.
282
283 If you don't know what to do here, say N.
284
285 config X86_X2APIC
286 bool "Support x2apic"
287 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
288 ---help---
289 This enables x2apic support on CPUs that have this feature.
290
291 This allows 32-bit apic IDs (so it can support very large systems),
292 and accesses the local apic via MSRs not via mmio.
293
294 If you don't know what to do here, say N.
295
296 config X86_MPPARSE
297 bool "Enable MPS table" if ACPI
298 default y
299 depends on X86_LOCAL_APIC
300 ---help---
301 For old smp systems that do not have proper acpi support. Newer systems
302 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
303
304 config X86_BIGSMP
305 bool "Support for big SMP systems with more than 8 CPUs"
306 depends on X86_32 && SMP
307 ---help---
308 This option is needed for the systems that have more than 8 CPUs
309
310 if X86_32
311 config X86_EXTENDED_PLATFORM
312 bool "Support for extended (non-PC) x86 platforms"
313 default y
314 ---help---
315 If you disable this option then the kernel will only support
316 standard PC platforms. (which covers the vast majority of
317 systems out there.)
318
319 If you enable this option then you'll be able to select support
320 for the following (non-PC) 32 bit x86 platforms:
321 AMD Elan
322 NUMAQ (IBM/Sequent)
323 RDC R-321x SoC
324 SGI 320/540 (Visual Workstation)
325 STA2X11-based (e.g. Northville)
326 Summit/EXA (IBM x440)
327 Unisys ES7000 IA32 series
328 Moorestown MID devices
329
330 If you have one of these systems, or if you want to build a
331 generic distribution kernel, say Y here - otherwise say N.
332 endif
333
334 if X86_64
335 config X86_EXTENDED_PLATFORM
336 bool "Support for extended (non-PC) x86 platforms"
337 default y
338 ---help---
339 If you disable this option then the kernel will only support
340 standard PC platforms. (which covers the vast majority of
341 systems out there.)
342
343 If you enable this option then you'll be able to select support
344 for the following (non-PC) 64 bit x86 platforms:
345 Numascale NumaChip
346 ScaleMP vSMP
347 SGI Ultraviolet
348
349 If you have one of these systems, or if you want to build a
350 generic distribution kernel, say Y here - otherwise say N.
351 endif
352 # This is an alphabetically sorted list of 64 bit extended platforms
353 # Please maintain the alphabetic order if and when there are additions
354 config X86_NUMACHIP
355 bool "Numascale NumaChip"
356 depends on X86_64
357 depends on X86_EXTENDED_PLATFORM
358 depends on NUMA
359 depends on SMP
360 depends on X86_X2APIC
361 ---help---
362 Adds support for Numascale NumaChip large-SMP systems. Needed to
363 enable more than ~168 cores.
364 If you don't have one of these, you should say N here.
365
366 config X86_VSMP
367 bool "ScaleMP vSMP"
368 select PARAVIRT_GUEST
369 select PARAVIRT
370 depends on X86_64 && PCI
371 depends on X86_EXTENDED_PLATFORM
372 depends on SMP
373 ---help---
374 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
375 supposed to run on these EM64T-based machines. Only choose this option
376 if you have one of these machines.
377
378 config X86_UV
379 bool "SGI Ultraviolet"
380 depends on X86_64
381 depends on X86_EXTENDED_PLATFORM
382 depends on NUMA
383 depends on X86_X2APIC
384 ---help---
385 This option is needed in order to support SGI Ultraviolet systems.
386 If you don't have one of these, you should say N here.
387
388 # Following is an alphabetically sorted list of 32 bit extended platforms
389 # Please maintain the alphabetic order if and when there are additions
390
391 config X86_INTEL_CE
392 bool "CE4100 TV platform"
393 depends on PCI
394 depends on PCI_GODIRECT
395 depends on X86_32
396 depends on X86_EXTENDED_PLATFORM
397 select X86_REBOOTFIXUPS
398 select OF
399 select OF_EARLY_FLATTREE
400 select IRQ_DOMAIN
401 ---help---
402 Select for the Intel CE media processor (CE4100) SOC.
403 This option compiles in support for the CE4100 SOC for settop
404 boxes and media devices.
405
406 config X86_WANT_INTEL_MID
407 bool "Intel MID platform support"
408 depends on X86_32
409 depends on X86_EXTENDED_PLATFORM
410 ---help---
411 Select to build a kernel capable of supporting Intel MID platform
412 systems which do not have the PCI legacy interfaces (Moorestown,
413 Medfield). If you are building for a PC class system say N here.
414
415 if X86_WANT_INTEL_MID
416
417 config X86_INTEL_MID
418 bool
419
420 config X86_MDFLD
421 bool "Medfield MID platform"
422 depends on PCI
423 depends on PCI_GOANY
424 depends on X86_IO_APIC
425 select X86_INTEL_MID
426 select SFI
427 select DW_APB_TIMER
428 select APB_TIMER
429 select I2C
430 select SPI
431 select INTEL_SCU_IPC
432 select X86_PLATFORM_DEVICES
433 select MFD_INTEL_MSIC
434 ---help---
435 Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin
436 Internet Device(MID) platform.
437 Unlike standard x86 PCs, Medfield does not have many legacy devices
438 nor standard legacy replacement devices/features. e.g. Medfield does
439 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
440
441 endif
442
443 config X86_RDC321X
444 bool "RDC R-321x SoC"
445 depends on X86_32
446 depends on X86_EXTENDED_PLATFORM
447 select M486
448 select X86_REBOOTFIXUPS
449 ---help---
450 This option is needed for RDC R-321x system-on-chip, also known
451 as R-8610-(G).
452 If you don't have one of these chips, you should say N here.
453
454 config X86_32_NON_STANDARD
455 bool "Support non-standard 32-bit SMP architectures"
456 depends on X86_32 && SMP
457 depends on X86_EXTENDED_PLATFORM
458 ---help---
459 This option compiles in the NUMAQ, Summit, bigsmp, ES7000,
460 STA2X11, default subarchitectures. It is intended for a generic
461 binary kernel. If you select them all, kernel will probe it
462 one by one and will fallback to default.
463
464 # Alphabetically sorted list of Non standard 32 bit platforms
465
466 config X86_NUMAQ
467 bool "NUMAQ (IBM/Sequent)"
468 depends on X86_32_NON_STANDARD
469 depends on PCI
470 select NUMA
471 select X86_MPPARSE
472 ---help---
473 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
474 NUMA multiquad box. This changes the way that processors are
475 bootstrapped, and uses Clustered Logical APIC addressing mode instead
476 of Flat Logical. You will need a new lynxer.elf file to flash your
477 firmware with - send email to <Martin.Bligh@us.ibm.com>.
478
479 config X86_SUPPORTS_MEMORY_FAILURE
480 def_bool y
481 # MCE code calls memory_failure():
482 depends on X86_MCE
483 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
484 depends on !X86_NUMAQ
485 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
486 depends on X86_64 || !SPARSEMEM
487 select ARCH_SUPPORTS_MEMORY_FAILURE
488
489 config X86_VISWS
490 bool "SGI 320/540 (Visual Workstation)"
491 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
492 depends on X86_32_NON_STANDARD
493 ---help---
494 The SGI Visual Workstation series is an IA32-based workstation
495 based on SGI systems chips with some legacy PC hardware attached.
496
497 Say Y here to create a kernel to run on the SGI 320 or 540.
498
499 A kernel compiled for the Visual Workstation will run on general
500 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
501
502 config STA2X11
503 bool "STA2X11 Companion Chip Support"
504 depends on X86_32_NON_STANDARD && PCI
505 select X86_DEV_DMA_OPS
506 select X86_DMA_REMAP
507 select SWIOTLB
508 select MFD_STA2X11
509 select ARCH_REQUIRE_GPIOLIB
510 default n
511 ---help---
512 This adds support for boards based on the STA2X11 IO-Hub,
513 a.k.a. "ConneXt". The chip is used in place of the standard
514 PC chipset, so all "standard" peripherals are missing. If this
515 option is selected the kernel will still be able to boot on
516 standard PC machines.
517
518 config X86_SUMMIT
519 bool "Summit/EXA (IBM x440)"
520 depends on X86_32_NON_STANDARD
521 ---help---
522 This option is needed for IBM systems that use the Summit/EXA chipset.
523 In particular, it is needed for the x440.
524
525 config X86_ES7000
526 bool "Unisys ES7000 IA32 series"
527 depends on X86_32_NON_STANDARD && X86_BIGSMP
528 ---help---
529 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
530 supposed to run on an IA32-based Unisys ES7000 system.
531
532 config X86_32_IRIS
533 tristate "Eurobraille/Iris poweroff module"
534 depends on X86_32
535 ---help---
536 The Iris machines from EuroBraille do not have APM or ACPI support
537 to shut themselves down properly. A special I/O sequence is
538 needed to do so, which is what this module does at
539 kernel shutdown.
540
541 This is only for Iris machines from EuroBraille.
542
543 If unused, say N.
544
545 config SCHED_OMIT_FRAME_POINTER
546 def_bool y
547 prompt "Single-depth WCHAN output"
548 depends on X86
549 ---help---
550 Calculate simpler /proc/<PID>/wchan values. If this option
551 is disabled then wchan values will recurse back to the
552 caller function. This provides more accurate wchan values,
553 at the expense of slightly more scheduling overhead.
554
555 If in doubt, say "Y".
556
557 menuconfig PARAVIRT_GUEST
558 bool "Paravirtualized guest support"
559 ---help---
560 Say Y here to get to see options related to running Linux under
561 various hypervisors. This option alone does not add any kernel code.
562
563 If you say N, all options in this submenu will be skipped and disabled.
564
565 if PARAVIRT_GUEST
566
567 config PARAVIRT_TIME_ACCOUNTING
568 bool "Paravirtual steal time accounting"
569 select PARAVIRT
570 default n
571 ---help---
572 Select this option to enable fine granularity task steal time
573 accounting. Time spent executing other tasks in parallel with
574 the current vCPU is discounted from the vCPU power. To account for
575 that, there can be a small performance impact.
576
577 If in doubt, say N here.
578
579 source "arch/x86/xen/Kconfig"
580
581 config KVM_CLOCK
582 bool "KVM paravirtualized clock"
583 select PARAVIRT
584 select PARAVIRT_CLOCK
585 ---help---
586 Turning on this option will allow you to run a paravirtualized clock
587 when running over the KVM hypervisor. Instead of relying on a PIT
588 (or probably other) emulation by the underlying device model, the host
589 provides the guest with timing infrastructure such as time of day, and
590 system time
591
592 config KVM_GUEST
593 bool "KVM Guest support"
594 select PARAVIRT
595 ---help---
596 This option enables various optimizations for running under the KVM
597 hypervisor.
598
599 source "arch/x86/lguest/Kconfig"
600
601 config PARAVIRT
602 bool "Enable paravirtualization code"
603 ---help---
604 This changes the kernel so it can modify itself when it is run
605 under a hypervisor, potentially improving performance significantly
606 over full virtualization. However, when run without a hypervisor
607 the kernel is theoretically slower and slightly larger.
608
609 config PARAVIRT_SPINLOCKS
610 bool "Paravirtualization layer for spinlocks"
611 depends on PARAVIRT && SMP && EXPERIMENTAL
612 ---help---
613 Paravirtualized spinlocks allow a pvops backend to replace the
614 spinlock implementation with something virtualization-friendly
615 (for example, block the virtual CPU rather than spinning).
616
617 Unfortunately the downside is an up to 5% performance hit on
618 native kernels, with various workloads.
619
620 If you are unsure how to answer this question, answer N.
621
622 config PARAVIRT_CLOCK
623 bool
624
625 endif
626
627 config PARAVIRT_DEBUG
628 bool "paravirt-ops debugging"
629 depends on PARAVIRT && DEBUG_KERNEL
630 ---help---
631 Enable to debug paravirt_ops internals. Specifically, BUG if
632 a paravirt_op is missing when it is called.
633
634 config NO_BOOTMEM
635 def_bool y
636
637 config MEMTEST
638 bool "Memtest"
639 ---help---
640 This option adds a kernel parameter 'memtest', which allows memtest
641 to be set.
642 memtest=0, mean disabled; -- default
643 memtest=1, mean do 1 test pattern;
644 ...
645 memtest=4, mean do 4 test patterns.
646 If you are unsure how to answer this question, answer N.
647
648 config X86_SUMMIT_NUMA
649 def_bool y
650 depends on X86_32 && NUMA && X86_32_NON_STANDARD
651
652 config X86_CYCLONE_TIMER
653 def_bool y
654 depends on X86_SUMMIT
655
656 source "arch/x86/Kconfig.cpu"
657
658 config HPET_TIMER
659 def_bool X86_64
660 prompt "HPET Timer Support" if X86_32
661 ---help---
662 Use the IA-PC HPET (High Precision Event Timer) to manage
663 time in preference to the PIT and RTC, if a HPET is
664 present.
665 HPET is the next generation timer replacing legacy 8254s.
666 The HPET provides a stable time base on SMP
667 systems, unlike the TSC, but it is more expensive to access,
668 as it is off-chip. You can find the HPET spec at
669 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
670
671 You can safely choose Y here. However, HPET will only be
672 activated if the platform and the BIOS support this feature.
673 Otherwise the 8254 will be used for timing services.
674
675 Choose N to continue using the legacy 8254 timer.
676
677 config HPET_EMULATE_RTC
678 def_bool y
679 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
680
681 config APB_TIMER
682 def_bool y if X86_INTEL_MID
683 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
684 select DW_APB_TIMER
685 depends on X86_INTEL_MID && SFI
686 help
687 APB timer is the replacement for 8254, HPET on X86 MID platforms.
688 The APBT provides a stable time base on SMP
689 systems, unlike the TSC, but it is more expensive to access,
690 as it is off-chip. APB timers are always running regardless of CPU
691 C states, they are used as per CPU clockevent device when possible.
692
693 # Mark as expert because too many people got it wrong.
694 # The code disables itself when not needed.
695 config DMI
696 default y
697 bool "Enable DMI scanning" if EXPERT
698 ---help---
699 Enabled scanning of DMI to identify machine quirks. Say Y
700 here unless you have verified that your setup is not
701 affected by entries in the DMI blacklist. Required by PNP
702 BIOS code.
703
704 config GART_IOMMU
705 bool "GART IOMMU support" if EXPERT
706 default y
707 select SWIOTLB
708 depends on X86_64 && PCI && AMD_NB
709 ---help---
710 Support for full DMA access of devices with 32bit memory access only
711 on systems with more than 3GB. This is usually needed for USB,
712 sound, many IDE/SATA chipsets and some other devices.
713 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
714 based hardware IOMMU and a software bounce buffer based IOMMU used
715 on Intel systems and as fallback.
716 The code is only active when needed (enough memory and limited
717 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
718 too.
719
720 config CALGARY_IOMMU
721 bool "IBM Calgary IOMMU support"
722 select SWIOTLB
723 depends on X86_64 && PCI && EXPERIMENTAL
724 ---help---
725 Support for hardware IOMMUs in IBM's xSeries x366 and x460
726 systems. Needed to run systems with more than 3GB of memory
727 properly with 32-bit PCI devices that do not support DAC
728 (Double Address Cycle). Calgary also supports bus level
729 isolation, where all DMAs pass through the IOMMU. This
730 prevents them from going anywhere except their intended
731 destination. This catches hard-to-find kernel bugs and
732 mis-behaving drivers and devices that do not use the DMA-API
733 properly to set up their DMA buffers. The IOMMU can be
734 turned off at boot time with the iommu=off parameter.
735 Normally the kernel will make the right choice by itself.
736 If unsure, say Y.
737
738 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
739 def_bool y
740 prompt "Should Calgary be enabled by default?"
741 depends on CALGARY_IOMMU
742 ---help---
743 Should Calgary be enabled by default? if you choose 'y', Calgary
744 will be used (if it exists). If you choose 'n', Calgary will not be
745 used even if it exists. If you choose 'n' and would like to use
746 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
747 If unsure, say Y.
748
749 # need this always selected by IOMMU for the VIA workaround
750 config SWIOTLB
751 def_bool y if X86_64
752 ---help---
753 Support for software bounce buffers used on x86-64 systems
754 which don't have a hardware IOMMU. Using this PCI devices
755 which can only access 32-bits of memory can be used on systems
756 with more than 3 GB of memory.
757 If unsure, say Y.
758
759 config IOMMU_HELPER
760 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
761
762 config MAXSMP
763 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
764 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
765 select CPUMASK_OFFSTACK
766 ---help---
767 Enable maximum number of CPUS and NUMA Nodes for this architecture.
768 If unsure, say N.
769
770 config NR_CPUS
771 int "Maximum number of CPUs" if SMP && !MAXSMP
772 range 2 8 if SMP && X86_32 && !X86_BIGSMP
773 range 2 512 if SMP && !MAXSMP
774 default "1" if !SMP
775 default "4096" if MAXSMP
776 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
777 default "8" if SMP
778 ---help---
779 This allows you to specify the maximum number of CPUs which this
780 kernel will support. The maximum supported value is 512 and the
781 minimum value which makes sense is 2.
782
783 This is purely to save memory - each supported CPU adds
784 approximately eight kilobytes to the kernel image.
785
786 config SCHED_SMT
787 bool "SMT (Hyperthreading) scheduler support"
788 depends on X86_HT
789 ---help---
790 SMT scheduler support improves the CPU scheduler's decision making
791 when dealing with Intel Pentium 4 chips with HyperThreading at a
792 cost of slightly increased overhead in some places. If unsure say
793 N here.
794
795 config SCHED_MC
796 def_bool y
797 prompt "Multi-core scheduler support"
798 depends on X86_HT
799 ---help---
800 Multi-core scheduler support improves the CPU scheduler's decision
801 making when dealing with multi-core CPU chips at a cost of slightly
802 increased overhead in some places. If unsure say N here.
803
804 source "kernel/Kconfig.preempt"
805
806 config X86_UP_APIC
807 bool "Local APIC support on uniprocessors"
808 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
809 ---help---
810 A local APIC (Advanced Programmable Interrupt Controller) is an
811 integrated interrupt controller in the CPU. If you have a single-CPU
812 system which has a processor with a local APIC, you can say Y here to
813 enable and use it. If you say Y here even though your machine doesn't
814 have a local APIC, then the kernel will still run with no slowdown at
815 all. The local APIC supports CPU-generated self-interrupts (timer,
816 performance counters), and the NMI watchdog which detects hard
817 lockups.
818
819 config X86_UP_IOAPIC
820 bool "IO-APIC support on uniprocessors"
821 depends on X86_UP_APIC
822 ---help---
823 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
824 SMP-capable replacement for PC-style interrupt controllers. Most
825 SMP systems and many recent uniprocessor systems have one.
826
827 If you have a single-CPU system with an IO-APIC, you can say Y here
828 to use it. If you say Y here even though your machine doesn't have
829 an IO-APIC, then the kernel will still run with no slowdown at all.
830
831 config X86_LOCAL_APIC
832 def_bool y
833 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
834
835 config X86_IO_APIC
836 def_bool y
837 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC
838
839 config X86_VISWS_APIC
840 def_bool y
841 depends on X86_32 && X86_VISWS
842
843 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
844 bool "Reroute for broken boot IRQs"
845 depends on X86_IO_APIC
846 ---help---
847 This option enables a workaround that fixes a source of
848 spurious interrupts. This is recommended when threaded
849 interrupt handling is used on systems where the generation of
850 superfluous "boot interrupts" cannot be disabled.
851
852 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
853 entry in the chipset's IO-APIC is masked (as, e.g. the RT
854 kernel does during interrupt handling). On chipsets where this
855 boot IRQ generation cannot be disabled, this workaround keeps
856 the original IRQ line masked so that only the equivalent "boot
857 IRQ" is delivered to the CPUs. The workaround also tells the
858 kernel to set up the IRQ handler on the boot IRQ line. In this
859 way only one interrupt is delivered to the kernel. Otherwise
860 the spurious second interrupt may cause the kernel to bring
861 down (vital) interrupt lines.
862
863 Only affects "broken" chipsets. Interrupt sharing may be
864 increased on these systems.
865
866 config X86_MCE
867 bool "Machine Check / overheating reporting"
868 ---help---
869 Machine Check support allows the processor to notify the
870 kernel if it detects a problem (e.g. overheating, data corruption).
871 The action the kernel takes depends on the severity of the problem,
872 ranging from warning messages to halting the machine.
873
874 config X86_MCE_INTEL
875 def_bool y
876 prompt "Intel MCE features"
877 depends on X86_MCE && X86_LOCAL_APIC
878 ---help---
879 Additional support for intel specific MCE features such as
880 the thermal monitor.
881
882 config X86_MCE_AMD
883 def_bool y
884 prompt "AMD MCE features"
885 depends on X86_MCE && X86_LOCAL_APIC
886 ---help---
887 Additional support for AMD specific MCE features such as
888 the DRAM Error Threshold.
889
890 config X86_ANCIENT_MCE
891 bool "Support for old Pentium 5 / WinChip machine checks"
892 depends on X86_32 && X86_MCE
893 ---help---
894 Include support for machine check handling on old Pentium 5 or WinChip
895 systems. These typically need to be enabled explicitely on the command
896 line.
897
898 config X86_MCE_THRESHOLD
899 depends on X86_MCE_AMD || X86_MCE_INTEL
900 def_bool y
901
902 config X86_MCE_INJECT
903 depends on X86_MCE
904 tristate "Machine check injector support"
905 ---help---
906 Provide support for injecting machine checks for testing purposes.
907 If you don't know what a machine check is and you don't do kernel
908 QA it is safe to say n.
909
910 config X86_THERMAL_VECTOR
911 def_bool y
912 depends on X86_MCE_INTEL
913
914 config VM86
915 bool "Enable VM86 support" if EXPERT
916 default y
917 depends on X86_32
918 ---help---
919 This option is required by programs like DOSEMU to run 16-bit legacy
920 code on X86 processors. It also may be needed by software like
921 XFree86 to initialize some video cards via BIOS. Disabling this
922 option saves about 6k.
923
924 config TOSHIBA
925 tristate "Toshiba Laptop support"
926 depends on X86_32
927 ---help---
928 This adds a driver to safely access the System Management Mode of
929 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
930 not work on models with a Phoenix BIOS. The System Management Mode
931 is used to set the BIOS and power saving options on Toshiba portables.
932
933 For information on utilities to make use of this driver see the
934 Toshiba Linux utilities web site at:
935 <http://www.buzzard.org.uk/toshiba/>.
936
937 Say Y if you intend to run this kernel on a Toshiba portable.
938 Say N otherwise.
939
940 config I8K
941 tristate "Dell laptop support"
942 select HWMON
943 ---help---
944 This adds a driver to safely access the System Management Mode
945 of the CPU on the Dell Inspiron 8000. The System Management Mode
946 is used to read cpu temperature and cooling fan status and to
947 control the fans on the I8K portables.
948
949 This driver has been tested only on the Inspiron 8000 but it may
950 also work with other Dell laptops. You can force loading on other
951 models by passing the parameter `force=1' to the module. Use at
952 your own risk.
953
954 For information on utilities to make use of this driver see the
955 I8K Linux utilities web site at:
956 <http://people.debian.org/~dz/i8k/>
957
958 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
959 Say N otherwise.
960
961 config X86_REBOOTFIXUPS
962 bool "Enable X86 board specific fixups for reboot"
963 depends on X86_32
964 ---help---
965 This enables chipset and/or board specific fixups to be done
966 in order to get reboot to work correctly. This is only needed on
967 some combinations of hardware and BIOS. The symptom, for which
968 this config is intended, is when reboot ends with a stalled/hung
969 system.
970
971 Currently, the only fixup is for the Geode machines using
972 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
973
974 Say Y if you want to enable the fixup. Currently, it's safe to
975 enable this option even if you don't need it.
976 Say N otherwise.
977
978 config MICROCODE
979 tristate "/dev/cpu/microcode - microcode support"
980 select FW_LOADER
981 ---help---
982 If you say Y here, you will be able to update the microcode on
983 certain Intel and AMD processors. The Intel support is for the
984 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
985 Pentium 4, Xeon etc. The AMD support is for family 0x10 and
986 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
987 You will obviously need the actual microcode binary data itself
988 which is not shipped with the Linux kernel.
989
990 This option selects the general module only, you need to select
991 at least one vendor specific module as well.
992
993 To compile this driver as a module, choose M here: the
994 module will be called microcode.
995
996 config MICROCODE_INTEL
997 bool "Intel microcode patch loading support"
998 depends on MICROCODE
999 default MICROCODE
1000 select FW_LOADER
1001 ---help---
1002 This options enables microcode patch loading support for Intel
1003 processors.
1004
1005 For latest news and information on obtaining all the required
1006 Intel ingredients for this driver, check:
1007 <http://www.urbanmyth.org/microcode/>.
1008
1009 config MICROCODE_AMD
1010 bool "AMD microcode patch loading support"
1011 depends on MICROCODE
1012 select FW_LOADER
1013 ---help---
1014 If you select this option, microcode patch loading support for AMD
1015 processors will be enabled.
1016
1017 config MICROCODE_OLD_INTERFACE
1018 def_bool y
1019 depends on MICROCODE
1020
1021 config X86_MSR
1022 tristate "/dev/cpu/*/msr - Model-specific register support"
1023 ---help---
1024 This device gives privileged processes access to the x86
1025 Model-Specific Registers (MSRs). It is a character device with
1026 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1027 MSR accesses are directed to a specific CPU on multi-processor
1028 systems.
1029
1030 config X86_CPUID
1031 tristate "/dev/cpu/*/cpuid - CPU information support"
1032 ---help---
1033 This device gives processes access to the x86 CPUID instruction to
1034 be executed on a specific processor. It is a character device
1035 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1036 /dev/cpu/31/cpuid.
1037
1038 choice
1039 prompt "High Memory Support"
1040 default HIGHMEM64G if X86_NUMAQ
1041 default HIGHMEM4G
1042 depends on X86_32
1043
1044 config NOHIGHMEM
1045 bool "off"
1046 depends on !X86_NUMAQ
1047 ---help---
1048 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1049 However, the address space of 32-bit x86 processors is only 4
1050 Gigabytes large. That means that, if you have a large amount of
1051 physical memory, not all of it can be "permanently mapped" by the
1052 kernel. The physical memory that's not permanently mapped is called
1053 "high memory".
1054
1055 If you are compiling a kernel which will never run on a machine with
1056 more than 1 Gigabyte total physical RAM, answer "off" here (default
1057 choice and suitable for most users). This will result in a "3GB/1GB"
1058 split: 3GB are mapped so that each process sees a 3GB virtual memory
1059 space and the remaining part of the 4GB virtual memory space is used
1060 by the kernel to permanently map as much physical memory as
1061 possible.
1062
1063 If the machine has between 1 and 4 Gigabytes physical RAM, then
1064 answer "4GB" here.
1065
1066 If more than 4 Gigabytes is used then answer "64GB" here. This
1067 selection turns Intel PAE (Physical Address Extension) mode on.
1068 PAE implements 3-level paging on IA32 processors. PAE is fully
1069 supported by Linux, PAE mode is implemented on all recent Intel
1070 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1071 then the kernel will not boot on CPUs that don't support PAE!
1072
1073 The actual amount of total physical memory will either be
1074 auto detected or can be forced by using a kernel command line option
1075 such as "mem=256M". (Try "man bootparam" or see the documentation of
1076 your boot loader (lilo or loadlin) about how to pass options to the
1077 kernel at boot time.)
1078
1079 If unsure, say "off".
1080
1081 config HIGHMEM4G
1082 bool "4GB"
1083 depends on !X86_NUMAQ
1084 ---help---
1085 Select this if you have a 32-bit processor and between 1 and 4
1086 gigabytes of physical RAM.
1087
1088 config HIGHMEM64G
1089 bool "64GB"
1090 depends on !M386 && !M486
1091 select X86_PAE
1092 ---help---
1093 Select this if you have a 32-bit processor and more than 4
1094 gigabytes of physical RAM.
1095
1096 endchoice
1097
1098 choice
1099 depends on EXPERIMENTAL
1100 prompt "Memory split" if EXPERT
1101 default VMSPLIT_3G
1102 depends on X86_32
1103 ---help---
1104 Select the desired split between kernel and user memory.
1105
1106 If the address range available to the kernel is less than the
1107 physical memory installed, the remaining memory will be available
1108 as "high memory". Accessing high memory is a little more costly
1109 than low memory, as it needs to be mapped into the kernel first.
1110 Note that increasing the kernel address space limits the range
1111 available to user programs, making the address space there
1112 tighter. Selecting anything other than the default 3G/1G split
1113 will also likely make your kernel incompatible with binary-only
1114 kernel modules.
1115
1116 If you are not absolutely sure what you are doing, leave this
1117 option alone!
1118
1119 config VMSPLIT_3G
1120 bool "3G/1G user/kernel split"
1121 config VMSPLIT_3G_OPT
1122 depends on !X86_PAE
1123 bool "3G/1G user/kernel split (for full 1G low memory)"
1124 config VMSPLIT_2G
1125 bool "2G/2G user/kernel split"
1126 config VMSPLIT_2G_OPT
1127 depends on !X86_PAE
1128 bool "2G/2G user/kernel split (for full 2G low memory)"
1129 config VMSPLIT_1G
1130 bool "1G/3G user/kernel split"
1131 endchoice
1132
1133 config PAGE_OFFSET
1134 hex
1135 default 0xB0000000 if VMSPLIT_3G_OPT
1136 default 0x80000000 if VMSPLIT_2G
1137 default 0x78000000 if VMSPLIT_2G_OPT
1138 default 0x40000000 if VMSPLIT_1G
1139 default 0xC0000000
1140 depends on X86_32
1141
1142 config HIGHMEM
1143 def_bool y
1144 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1145
1146 config X86_PAE
1147 bool "PAE (Physical Address Extension) Support"
1148 depends on X86_32 && !HIGHMEM4G
1149 ---help---
1150 PAE is required for NX support, and furthermore enables
1151 larger swapspace support for non-overcommit purposes. It
1152 has the cost of more pagetable lookup overhead, and also
1153 consumes more pagetable space per process.
1154
1155 config ARCH_PHYS_ADDR_T_64BIT
1156 def_bool X86_64 || X86_PAE
1157
1158 config ARCH_DMA_ADDR_T_64BIT
1159 def_bool X86_64 || HIGHMEM64G
1160
1161 config DIRECT_GBPAGES
1162 bool "Enable 1GB pages for kernel pagetables" if EXPERT
1163 default y
1164 depends on X86_64
1165 ---help---
1166 Allow the kernel linear mapping to use 1GB pages on CPUs that
1167 support it. This can improve the kernel's performance a tiny bit by
1168 reducing TLB pressure. If in doubt, say "Y".
1169
1170 # Common NUMA Features
1171 config NUMA
1172 bool "Numa Memory Allocation and Scheduler Support"
1173 depends on SMP
1174 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1175 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1176 ---help---
1177 Enable NUMA (Non Uniform Memory Access) support.
1178
1179 The kernel will try to allocate memory used by a CPU on the
1180 local memory controller of the CPU and add some more
1181 NUMA awareness to the kernel.
1182
1183 For 64-bit this is recommended if the system is Intel Core i7
1184 (or later), AMD Opteron, or EM64T NUMA.
1185
1186 For 32-bit this is only needed on (rare) 32-bit-only platforms
1187 that support NUMA topologies, such as NUMAQ / Summit, or if you
1188 boot a 32-bit kernel on a 64-bit NUMA platform.
1189
1190 Otherwise, you should say N.
1191
1192 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1193 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1194
1195 config AMD_NUMA
1196 def_bool y
1197 prompt "Old style AMD Opteron NUMA detection"
1198 depends on X86_64 && NUMA && PCI
1199 ---help---
1200 Enable AMD NUMA node topology detection. You should say Y here if
1201 you have a multi processor AMD system. This uses an old method to
1202 read the NUMA configuration directly from the builtin Northbridge
1203 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1204 which also takes priority if both are compiled in.
1205
1206 config X86_64_ACPI_NUMA
1207 def_bool y
1208 prompt "ACPI NUMA detection"
1209 depends on X86_64 && NUMA && ACPI && PCI
1210 select ACPI_NUMA
1211 ---help---
1212 Enable ACPI SRAT based node topology detection.
1213
1214 # Some NUMA nodes have memory ranges that span
1215 # other nodes. Even though a pfn is valid and
1216 # between a node's start and end pfns, it may not
1217 # reside on that node. See memmap_init_zone()
1218 # for details.
1219 config NODES_SPAN_OTHER_NODES
1220 def_bool y
1221 depends on X86_64_ACPI_NUMA
1222
1223 config NUMA_EMU
1224 bool "NUMA emulation"
1225 depends on NUMA
1226 ---help---
1227 Enable NUMA emulation. A flat machine will be split
1228 into virtual nodes when booted with "numa=fake=N", where N is the
1229 number of nodes. This is only useful for debugging.
1230
1231 config NODES_SHIFT
1232 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1233 range 1 10
1234 default "10" if MAXSMP
1235 default "6" if X86_64
1236 default "4" if X86_NUMAQ
1237 default "3"
1238 depends on NEED_MULTIPLE_NODES
1239 ---help---
1240 Specify the maximum number of NUMA Nodes available on the target
1241 system. Increases memory reserved to accommodate various tables.
1242
1243 config HAVE_ARCH_ALLOC_REMAP
1244 def_bool y
1245 depends on X86_32 && NUMA
1246
1247 config ARCH_HAVE_MEMORY_PRESENT
1248 def_bool y
1249 depends on X86_32 && DISCONTIGMEM
1250
1251 config NEED_NODE_MEMMAP_SIZE
1252 def_bool y
1253 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1254
1255 config ARCH_FLATMEM_ENABLE
1256 def_bool y
1257 depends on X86_32 && !NUMA
1258
1259 config ARCH_DISCONTIGMEM_ENABLE
1260 def_bool y
1261 depends on NUMA && X86_32
1262
1263 config ARCH_DISCONTIGMEM_DEFAULT
1264 def_bool y
1265 depends on NUMA && X86_32
1266
1267 config ARCH_SPARSEMEM_ENABLE
1268 def_bool y
1269 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1270 select SPARSEMEM_STATIC if X86_32
1271 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1272
1273 config ARCH_SPARSEMEM_DEFAULT
1274 def_bool y
1275 depends on X86_64
1276
1277 config ARCH_SELECT_MEMORY_MODEL
1278 def_bool y
1279 depends on ARCH_SPARSEMEM_ENABLE
1280
1281 config ARCH_MEMORY_PROBE
1282 def_bool X86_64
1283 depends on MEMORY_HOTPLUG
1284
1285 config ARCH_PROC_KCORE_TEXT
1286 def_bool y
1287 depends on X86_64 && PROC_KCORE
1288
1289 config ILLEGAL_POINTER_VALUE
1290 hex
1291 default 0 if X86_32
1292 default 0xdead000000000000 if X86_64
1293
1294 source "mm/Kconfig"
1295
1296 config HIGHPTE
1297 bool "Allocate 3rd-level pagetables from highmem"
1298 depends on HIGHMEM
1299 ---help---
1300 The VM uses one page table entry for each page of physical memory.
1301 For systems with a lot of RAM, this can be wasteful of precious
1302 low memory. Setting this option will put user-space page table
1303 entries in high memory.
1304
1305 config X86_CHECK_BIOS_CORRUPTION
1306 bool "Check for low memory corruption"
1307 ---help---
1308 Periodically check for memory corruption in low memory, which
1309 is suspected to be caused by BIOS. Even when enabled in the
1310 configuration, it is disabled at runtime. Enable it by
1311 setting "memory_corruption_check=1" on the kernel command
1312 line. By default it scans the low 64k of memory every 60
1313 seconds; see the memory_corruption_check_size and
1314 memory_corruption_check_period parameters in
1315 Documentation/kernel-parameters.txt to adjust this.
1316
1317 When enabled with the default parameters, this option has
1318 almost no overhead, as it reserves a relatively small amount
1319 of memory and scans it infrequently. It both detects corruption
1320 and prevents it from affecting the running system.
1321
1322 It is, however, intended as a diagnostic tool; if repeatable
1323 BIOS-originated corruption always affects the same memory,
1324 you can use memmap= to prevent the kernel from using that
1325 memory.
1326
1327 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1328 bool "Set the default setting of memory_corruption_check"
1329 depends on X86_CHECK_BIOS_CORRUPTION
1330 default y
1331 ---help---
1332 Set whether the default state of memory_corruption_check is
1333 on or off.
1334
1335 config X86_RESERVE_LOW
1336 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1337 default 64
1338 range 4 640
1339 ---help---
1340 Specify the amount of low memory to reserve for the BIOS.
1341
1342 The first page contains BIOS data structures that the kernel
1343 must not use, so that page must always be reserved.
1344
1345 By default we reserve the first 64K of physical RAM, as a
1346 number of BIOSes are known to corrupt that memory range
1347 during events such as suspend/resume or monitor cable
1348 insertion, so it must not be used by the kernel.
1349
1350 You can set this to 4 if you are absolutely sure that you
1351 trust the BIOS to get all its memory reservations and usages
1352 right. If you know your BIOS have problems beyond the
1353 default 64K area, you can set this to 640 to avoid using the
1354 entire low memory range.
1355
1356 If you have doubts about the BIOS (e.g. suspend/resume does
1357 not work or there's kernel crashes after certain hardware
1358 hotplug events) then you might want to enable
1359 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1360 typical corruption patterns.
1361
1362 Leave this to the default value of 64 if you are unsure.
1363
1364 config MATH_EMULATION
1365 bool
1366 prompt "Math emulation" if X86_32
1367 ---help---
1368 Linux can emulate a math coprocessor (used for floating point
1369 operations) if you don't have one. 486DX and Pentium processors have
1370 a math coprocessor built in, 486SX and 386 do not, unless you added
1371 a 487DX or 387, respectively. (The messages during boot time can
1372 give you some hints here ["man dmesg"].) Everyone needs either a
1373 coprocessor or this emulation.
1374
1375 If you don't have a math coprocessor, you need to say Y here; if you
1376 say Y here even though you have a coprocessor, the coprocessor will
1377 be used nevertheless. (This behavior can be changed with the kernel
1378 command line option "no387", which comes handy if your coprocessor
1379 is broken. Try "man bootparam" or see the documentation of your boot
1380 loader (lilo or loadlin) about how to pass options to the kernel at
1381 boot time.) This means that it is a good idea to say Y here if you
1382 intend to use this kernel on different machines.
1383
1384 More information about the internals of the Linux math coprocessor
1385 emulation can be found in <file:arch/x86/math-emu/README>.
1386
1387 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1388 kernel, it won't hurt.
1389
1390 config MTRR
1391 def_bool y
1392 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1393 ---help---
1394 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1395 the Memory Type Range Registers (MTRRs) may be used to control
1396 processor access to memory ranges. This is most useful if you have
1397 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1398 allows bus write transfers to be combined into a larger transfer
1399 before bursting over the PCI/AGP bus. This can increase performance
1400 of image write operations 2.5 times or more. Saying Y here creates a
1401 /proc/mtrr file which may be used to manipulate your processor's
1402 MTRRs. Typically the X server should use this.
1403
1404 This code has a reasonably generic interface so that similar
1405 control registers on other processors can be easily supported
1406 as well:
1407
1408 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1409 Registers (ARRs) which provide a similar functionality to MTRRs. For
1410 these, the ARRs are used to emulate the MTRRs.
1411 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1412 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1413 write-combining. All of these processors are supported by this code
1414 and it makes sense to say Y here if you have one of them.
1415
1416 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1417 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1418 can lead to all sorts of problems, so it's good to say Y here.
1419
1420 You can safely say Y even if your machine doesn't have MTRRs, you'll
1421 just add about 9 KB to your kernel.
1422
1423 See <file:Documentation/x86/mtrr.txt> for more information.
1424
1425 config MTRR_SANITIZER
1426 def_bool y
1427 prompt "MTRR cleanup support"
1428 depends on MTRR
1429 ---help---
1430 Convert MTRR layout from continuous to discrete, so X drivers can
1431 add writeback entries.
1432
1433 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1434 The largest mtrr entry size for a continuous block can be set with
1435 mtrr_chunk_size.
1436
1437 If unsure, say Y.
1438
1439 config MTRR_SANITIZER_ENABLE_DEFAULT
1440 int "MTRR cleanup enable value (0-1)"
1441 range 0 1
1442 default "0"
1443 depends on MTRR_SANITIZER
1444 ---help---
1445 Enable mtrr cleanup default value
1446
1447 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1448 int "MTRR cleanup spare reg num (0-7)"
1449 range 0 7
1450 default "1"
1451 depends on MTRR_SANITIZER
1452 ---help---
1453 mtrr cleanup spare entries default, it can be changed via
1454 mtrr_spare_reg_nr=N on the kernel command line.
1455
1456 config X86_PAT
1457 def_bool y
1458 prompt "x86 PAT support" if EXPERT
1459 depends on MTRR
1460 ---help---
1461 Use PAT attributes to setup page level cache control.
1462
1463 PATs are the modern equivalents of MTRRs and are much more
1464 flexible than MTRRs.
1465
1466 Say N here if you see bootup problems (boot crash, boot hang,
1467 spontaneous reboots) or a non-working video driver.
1468
1469 If unsure, say Y.
1470
1471 config ARCH_USES_PG_UNCACHED
1472 def_bool y
1473 depends on X86_PAT
1474
1475 config ARCH_RANDOM
1476 def_bool y
1477 prompt "x86 architectural random number generator" if EXPERT
1478 ---help---
1479 Enable the x86 architectural RDRAND instruction
1480 (Intel Bull Mountain technology) to generate random numbers.
1481 If supported, this is a high bandwidth, cryptographically
1482 secure hardware random number generator.
1483
1484 config EFI
1485 bool "EFI runtime service support"
1486 depends on ACPI
1487 ---help---
1488 This enables the kernel to use EFI runtime services that are
1489 available (such as the EFI variable services).
1490
1491 This option is only useful on systems that have EFI firmware.
1492 In addition, you should use the latest ELILO loader available
1493 at <http://elilo.sourceforge.net> in order to take advantage
1494 of EFI runtime services. However, even with this option, the
1495 resultant kernel should continue to boot on existing non-EFI
1496 platforms.
1497
1498 config EFI_STUB
1499 bool "EFI stub support"
1500 depends on EFI
1501 ---help---
1502 This kernel feature allows a bzImage to be loaded directly
1503 by EFI firmware without the use of a bootloader.
1504
1505 See Documentation/x86/efi-stub.txt for more information.
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"
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 SCx200
2026 tristate "NatSemi SCx200 support"
2027 ---help---
2028 This provides basic support for National Semiconductor's
2029 (now AMD's) Geode processors. The driver probes for the
2030 PCI-IDs of several on-chip devices, so its a good dependency
2031 for other scx200_* drivers.
2032
2033 If compiled as a module, the driver is named scx200.
2034
2035 config SCx200HR_TIMER
2036 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2037 depends on SCx200
2038 default y
2039 ---help---
2040 This driver provides a clocksource built upon the on-chip
2041 27MHz high-resolution timer. Its also a workaround for
2042 NSC Geode SC-1100's buggy TSC, which loses time when the
2043 processor goes idle (as is done by the scheduler). The
2044 other workaround is idle=poll boot option.
2045
2046 config OLPC
2047 bool "One Laptop Per Child support"
2048 depends on !X86_PAE
2049 select GPIOLIB
2050 select OF
2051 select OF_PROMTREE
2052 select IRQ_DOMAIN
2053 ---help---
2054 Add support for detecting the unique features of the OLPC
2055 XO hardware.
2056
2057 config OLPC_XO1_PM
2058 bool "OLPC XO-1 Power Management"
2059 depends on OLPC && MFD_CS5535 && PM_SLEEP
2060 select MFD_CORE
2061 ---help---
2062 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2063
2064 config OLPC_XO1_RTC
2065 bool "OLPC XO-1 Real Time Clock"
2066 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2067 ---help---
2068 Add support for the XO-1 real time clock, which can be used as a
2069 programmable wakeup source.
2070
2071 config OLPC_XO1_SCI
2072 bool "OLPC XO-1 SCI extras"
2073 depends on OLPC && OLPC_XO1_PM
2074 select POWER_SUPPLY
2075 select GPIO_CS5535
2076 select MFD_CORE
2077 ---help---
2078 Add support for SCI-based features of the OLPC XO-1 laptop:
2079 - EC-driven system wakeups
2080 - Power button
2081 - Ebook switch
2082 - Lid switch
2083 - AC adapter status updates
2084 - Battery status updates
2085
2086 config OLPC_XO15_SCI
2087 bool "OLPC XO-1.5 SCI extras"
2088 depends on OLPC && ACPI
2089 select POWER_SUPPLY
2090 ---help---
2091 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2092 - EC-driven system wakeups
2093 - AC adapter status updates
2094 - Battery status updates
2095
2096 config ALIX
2097 bool "PCEngines ALIX System Support (LED setup)"
2098 select GPIOLIB
2099 ---help---
2100 This option enables system support for the PCEngines ALIX.
2101 At present this just sets up LEDs for GPIO control on
2102 ALIX2/3/6 boards. However, other system specific setup should
2103 get added here.
2104
2105 Note: You must still enable the drivers for GPIO and LED support
2106 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2107
2108 Note: You have to set alix.force=1 for boards with Award BIOS.
2109
2110 config NET5501
2111 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2112 select GPIOLIB
2113 ---help---
2114 This option enables system support for the Soekris Engineering net5501.
2115
2116 config GEOS
2117 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2118 select GPIOLIB
2119 depends on DMI
2120 ---help---
2121 This option enables system support for the Traverse Technologies GEOS.
2122
2123 endif # X86_32
2124
2125 config AMD_NB
2126 def_bool y
2127 depends on CPU_SUP_AMD && PCI
2128
2129 source "drivers/pcmcia/Kconfig"
2130
2131 source "drivers/pci/hotplug/Kconfig"
2132
2133 config RAPIDIO
2134 bool "RapidIO support"
2135 depends on PCI
2136 default n
2137 help
2138 If you say Y here, the kernel will include drivers and
2139 infrastructure code to support RapidIO interconnect devices.
2140
2141 source "drivers/rapidio/Kconfig"
2142
2143 endmenu
2144
2145
2146 menu "Executable file formats / Emulations"
2147
2148 source "fs/Kconfig.binfmt"
2149
2150 config IA32_EMULATION
2151 bool "IA32 Emulation"
2152 depends on X86_64
2153 select COMPAT_BINFMT_ELF
2154 ---help---
2155 Include code to run legacy 32-bit programs under a
2156 64-bit kernel. You should likely turn this on, unless you're
2157 100% sure that you don't have any 32-bit programs left.
2158
2159 config IA32_AOUT
2160 tristate "IA32 a.out support"
2161 depends on IA32_EMULATION
2162 ---help---
2163 Support old a.out binaries in the 32bit emulation.
2164
2165 config X86_X32
2166 bool "x32 ABI for 64-bit mode (EXPERIMENTAL)"
2167 depends on X86_64 && IA32_EMULATION && EXPERIMENTAL
2168 ---help---
2169 Include code to run binaries for the x32 native 32-bit ABI
2170 for 64-bit processors. An x32 process gets access to the
2171 full 64-bit register file and wide data path while leaving
2172 pointers at 32 bits for smaller memory footprint.
2173
2174 You will need a recent binutils (2.22 or later) with
2175 elf32_x86_64 support enabled to compile a kernel with this
2176 option set.
2177
2178 config COMPAT
2179 def_bool y
2180 depends on IA32_EMULATION || X86_X32
2181 select ARCH_WANT_OLD_COMPAT_IPC
2182
2183 config COMPAT_FOR_U64_ALIGNMENT
2184 def_bool COMPAT
2185 depends on X86_64
2186
2187 config SYSVIPC_COMPAT
2188 def_bool y
2189 depends on COMPAT && SYSVIPC
2190
2191 config KEYS_COMPAT
2192 bool
2193 depends on COMPAT && KEYS
2194 default y
2195
2196 endmenu
2197
2198
2199 config HAVE_ATOMIC_IOMAP
2200 def_bool y
2201 depends on X86_32
2202
2203 config HAVE_TEXT_POKE_SMP
2204 bool
2205 select STOP_MACHINE if SMP
2206
2207 config X86_DEV_DMA_OPS
2208 bool
2209 depends on X86_64 || STA2X11
2210
2211 config X86_DMA_REMAP
2212 bool
2213 depends on STA2X11
2214
2215 source "net/Kconfig"
2216
2217 source "drivers/Kconfig"
2218
2219 source "drivers/firmware/Kconfig"
2220
2221 source "fs/Kconfig"
2222
2223 source "arch/x86/Kconfig.debug"
2224
2225 source "security/Kconfig"
2226
2227 source "crypto/Kconfig"
2228
2229 source "arch/x86/kvm/Kconfig"
2230
2231 source "lib/Kconfig"