Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/signal
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / x86 / Kconfig
1 # Select 32 or 64 bit
2 config 64BIT
3 bool "64-bit kernel" if ARCH = "x86"
4 default ARCH = "x86_64"
5 ---help---
6 Say yes to build a 64-bit kernel - formerly known as x86_64
7 Say no to build a 32-bit kernel - formerly known as i386
8
9 config X86_32
10 def_bool y
11 depends on !64BIT
12 select CLKSRC_I8253
13 select HAVE_UID16
14
15 config X86_64
16 def_bool y
17 depends on 64BIT
18 select X86_DEV_DMA_OPS
19
20 ### Arch settings
21 config X86
22 def_bool y
23 select HAVE_AOUT if X86_32
24 select HAVE_UNSTABLE_SCHED_CLOCK
25 select HAVE_IDE
26 select HAVE_OPROFILE
27 select HAVE_PCSPKR_PLATFORM
28 select HAVE_PERF_EVENTS
29 select HAVE_IRQ_WORK
30 select HAVE_IOREMAP_PROT
31 select HAVE_KPROBES
32 select HAVE_MEMBLOCK
33 select HAVE_MEMBLOCK_NODE_MAP
34 select ARCH_DISCARD_MEMBLOCK
35 select ARCH_WANT_OPTIONAL_GPIOLIB
36 select ARCH_WANT_FRAME_POINTERS
37 select HAVE_DMA_ATTRS
38 select HAVE_DMA_CONTIGUOUS if !SWIOTLB
39 select HAVE_KRETPROBES
40 select HAVE_OPTPROBES
41 select HAVE_FTRACE_MCOUNT_RECORD
42 select HAVE_FENTRY if X86_64
43 select HAVE_C_RECORDMCOUNT
44 select HAVE_DYNAMIC_FTRACE
45 select HAVE_FUNCTION_TRACER
46 select HAVE_FUNCTION_GRAPH_TRACER
47 select HAVE_FUNCTION_GRAPH_FP_TEST
48 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
49 select HAVE_SYSCALL_TRACEPOINTS
50 select SYSCTL_EXCEPTION_TRACE
51 select HAVE_KVM
52 select HAVE_ARCH_KGDB
53 select HAVE_ARCH_TRACEHOOK
54 select HAVE_GENERIC_DMA_COHERENT if X86_32
55 select HAVE_EFFICIENT_UNALIGNED_ACCESS
56 select USER_STACKTRACE_SUPPORT
57 select HAVE_REGS_AND_STACK_ACCESS_API
58 select HAVE_DMA_API_DEBUG
59 select HAVE_KERNEL_GZIP
60 select HAVE_KERNEL_BZIP2
61 select HAVE_KERNEL_LZMA
62 select HAVE_KERNEL_XZ
63 select HAVE_KERNEL_LZO
64 select HAVE_HW_BREAKPOINT
65 select HAVE_MIXED_BREAKPOINTS_REGS
66 select PERF_EVENTS
67 select HAVE_PERF_EVENTS_NMI
68 select HAVE_PERF_REGS
69 select HAVE_PERF_USER_STACK_DUMP
70 select HAVE_DEBUG_KMEMLEAK
71 select ANON_INODES
72 select HAVE_ALIGNED_STRUCT_PAGE if SLUB && !M386
73 select HAVE_CMPXCHG_LOCAL if !M386
74 select HAVE_CMPXCHG_DOUBLE
75 select HAVE_ARCH_KMEMCHECK
76 select HAVE_USER_RETURN_NOTIFIER
77 select ARCH_BINFMT_ELF_RANDOMIZE_PIE
78 select HAVE_ARCH_JUMP_LABEL
79 select HAVE_TEXT_POKE_SMP
80 select HAVE_GENERIC_HARDIRQS
81 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
82 select SPARSE_IRQ
83 select GENERIC_FIND_FIRST_BIT
84 select GENERIC_IRQ_PROBE
85 select GENERIC_PENDING_IRQ if SMP
86 select GENERIC_IRQ_SHOW
87 select GENERIC_CLOCKEVENTS_MIN_ADJUST
88 select IRQ_FORCED_THREADING
89 select USE_GENERIC_SMP_HELPERS if SMP
90 select HAVE_BPF_JIT if X86_64
91 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
92 select CLKEVT_I8253
93 select ARCH_HAVE_NMI_SAFE_CMPXCHG
94 select GENERIC_IOMAP
95 select DCACHE_WORD_ACCESS
96 select GENERIC_SMP_IDLE_THREAD
97 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
98 select HAVE_ARCH_SECCOMP_FILTER
99 select BUILDTIME_EXTABLE_SORT
100 select GENERIC_CMOS_UPDATE
101 select CLOCKSOURCE_WATCHDOG
102 select GENERIC_CLOCKEVENTS
103 select ARCH_CLOCKSOURCE_DATA if X86_64
104 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
105 select GENERIC_TIME_VSYSCALL if X86_64
106 select KTIME_SCALAR if X86_32
107 select GENERIC_STRNCPY_FROM_USER
108 select GENERIC_STRNLEN_USER
109 select HAVE_RCU_USER_QS if X86_64
110 select HAVE_IRQ_TIME_ACCOUNTING
111 select GENERIC_KERNEL_THREAD
112
113 config INSTRUCTION_DECODER
114 def_bool y
115 depends on KPROBES || PERF_EVENTS || UPROBES
116
117 config OUTPUT_FORMAT
118 string
119 default "elf32-i386" if X86_32
120 default "elf64-x86-64" if X86_64
121
122 config ARCH_DEFCONFIG
123 string
124 default "arch/x86/configs/i386_defconfig" if X86_32
125 default "arch/x86/configs/x86_64_defconfig" if X86_64
126
127 config LOCKDEP_SUPPORT
128 def_bool y
129
130 config STACKTRACE_SUPPORT
131 def_bool y
132
133 config HAVE_LATENCYTOP_SUPPORT
134 def_bool y
135
136 config MMU
137 def_bool y
138
139 config SBUS
140 bool
141
142 config NEED_DMA_MAP_STATE
143 def_bool y
144 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG
145
146 config NEED_SG_DMA_LENGTH
147 def_bool y
148
149 config GENERIC_ISA_DMA
150 def_bool y
151 depends on ISA_DMA_API
152
153 config GENERIC_BUG
154 def_bool y
155 depends on BUG
156 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
157
158 config GENERIC_BUG_RELATIVE_POINTERS
159 bool
160
161 config GENERIC_HWEIGHT
162 def_bool y
163
164 config GENERIC_GPIO
165 bool
166
167 config ARCH_MAY_HAVE_PC_FDC
168 def_bool y
169 depends on ISA_DMA_API
170
171 config RWSEM_GENERIC_SPINLOCK
172 def_bool y
173 depends on !X86_XADD
174
175 config RWSEM_XCHGADD_ALGORITHM
176 def_bool y
177 depends on X86_XADD
178
179 config GENERIC_CALIBRATE_DELAY
180 def_bool y
181
182 config ARCH_HAS_CPU_RELAX
183 def_bool y
184
185 config ARCH_HAS_DEFAULT_IDLE
186 def_bool y
187
188 config ARCH_HAS_CACHE_LINE_SIZE
189 def_bool y
190
191 config ARCH_HAS_CPU_AUTOPROBE
192 def_bool y
193
194 config HAVE_SETUP_PER_CPU_AREA
195 def_bool y
196
197 config NEED_PER_CPU_EMBED_FIRST_CHUNK
198 def_bool y
199
200 config NEED_PER_CPU_PAGE_FIRST_CHUNK
201 def_bool y
202
203 config ARCH_HIBERNATION_POSSIBLE
204 def_bool y
205
206 config ARCH_SUSPEND_POSSIBLE
207 def_bool y
208
209 config ZONE_DMA32
210 bool
211 default X86_64
212
213 config AUDIT_ARCH
214 bool
215 default X86_64
216
217 config ARCH_SUPPORTS_OPTIMIZED_INLINING
218 def_bool y
219
220 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
221 def_bool y
222
223 config HAVE_INTEL_TXT
224 def_bool y
225 depends on EXPERIMENTAL && INTEL_IOMMU && ACPI
226
227 config X86_32_SMP
228 def_bool y
229 depends on X86_32 && SMP
230
231 config X86_64_SMP
232 def_bool y
233 depends on X86_64 && SMP
234
235 config X86_HT
236 def_bool y
237 depends on SMP
238
239 config X86_32_LAZY_GS
240 def_bool y
241 depends on X86_32 && !CC_STACKPROTECTOR
242
243 config ARCH_HWEIGHT_CFLAGS
244 string
245 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
246 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
247
248 config ARCH_CPU_PROBE_RELEASE
249 def_bool y
250 depends on HOTPLUG_CPU
251
252 config ARCH_SUPPORTS_UPROBES
253 def_bool y
254
255 source "init/Kconfig"
256 source "kernel/Kconfig.freezer"
257
258 menu "Processor type and features"
259
260 config ZONE_DMA
261 bool "DMA memory allocation support" if EXPERT
262 default y
263 help
264 DMA memory allocation support allows devices with less than 32-bit
265 addressing to allocate within the first 16MB of address space.
266 Disable if no such devices will be used.
267
268 If unsure, say Y.
269
270 config SMP
271 bool "Symmetric multi-processing support"
272 ---help---
273 This enables support for systems with more than one CPU. If you have
274 a system with only one CPU, like most personal computers, say N. If
275 you have a system with more than one CPU, say Y.
276
277 If you say N here, the kernel will run on single and multiprocessor
278 machines, but will use only one CPU of a multiprocessor machine. If
279 you say Y here, the kernel will run on many, but not all,
280 singleprocessor machines. On a singleprocessor machine, the kernel
281 will run faster if you say N here.
282
283 Note that if you say Y here and choose architecture "586" or
284 "Pentium" under "Processor family", the kernel will not work on 486
285 architectures. Similarly, multiprocessor kernels for the "PPro"
286 architecture may not work on all Pentium based boards.
287
288 People using multiprocessor machines who say Y here should also say
289 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
290 Management" code will be disabled if you say Y here.
291
292 See also <file:Documentation/x86/i386/IO-APIC.txt>,
293 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
294 <http://www.tldp.org/docs.html#howto>.
295
296 If you don't know what to do here, say N.
297
298 config X86_X2APIC
299 bool "Support x2apic"
300 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
301 ---help---
302 This enables x2apic support on CPUs that have this feature.
303
304 This allows 32-bit apic IDs (so it can support very large systems),
305 and accesses the local apic via MSRs not via mmio.
306
307 If you don't know what to do here, say N.
308
309 config X86_MPPARSE
310 bool "Enable MPS table" if ACPI
311 default y
312 depends on X86_LOCAL_APIC
313 ---help---
314 For old smp systems that do not have proper acpi support. Newer systems
315 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
316
317 config X86_BIGSMP
318 bool "Support for big SMP systems with more than 8 CPUs"
319 depends on X86_32 && SMP
320 ---help---
321 This option is needed for the systems that have more than 8 CPUs
322
323 if X86_32
324 config X86_EXTENDED_PLATFORM
325 bool "Support for extended (non-PC) x86 platforms"
326 default y
327 ---help---
328 If you disable this option then the kernel will only support
329 standard PC platforms. (which covers the vast majority of
330 systems out there.)
331
332 If you enable this option then you'll be able to select support
333 for the following (non-PC) 32 bit x86 platforms:
334 AMD Elan
335 NUMAQ (IBM/Sequent)
336 RDC R-321x SoC
337 SGI 320/540 (Visual Workstation)
338 STA2X11-based (e.g. Northville)
339 Summit/EXA (IBM x440)
340 Unisys ES7000 IA32 series
341 Moorestown MID devices
342
343 If you have one of these systems, or if you want to build a
344 generic distribution kernel, say Y here - otherwise say N.
345 endif
346
347 if X86_64
348 config X86_EXTENDED_PLATFORM
349 bool "Support for extended (non-PC) x86 platforms"
350 default y
351 ---help---
352 If you disable this option then the kernel will only support
353 standard PC platforms. (which covers the vast majority of
354 systems out there.)
355
356 If you enable this option then you'll be able to select support
357 for the following (non-PC) 64 bit x86 platforms:
358 Numascale NumaChip
359 ScaleMP vSMP
360 SGI Ultraviolet
361
362 If you have one of these systems, or if you want to build a
363 generic distribution kernel, say Y here - otherwise say N.
364 endif
365 # This is an alphabetically sorted list of 64 bit extended platforms
366 # Please maintain the alphabetic order if and when there are additions
367 config X86_NUMACHIP
368 bool "Numascale NumaChip"
369 depends on X86_64
370 depends on X86_EXTENDED_PLATFORM
371 depends on NUMA
372 depends on SMP
373 depends on X86_X2APIC
374 ---help---
375 Adds support for Numascale NumaChip large-SMP systems. Needed to
376 enable more than ~168 cores.
377 If you don't have one of these, you should say N here.
378
379 config X86_VSMP
380 bool "ScaleMP vSMP"
381 select PARAVIRT_GUEST
382 select PARAVIRT
383 depends on X86_64 && PCI
384 depends on X86_EXTENDED_PLATFORM
385 depends on SMP
386 ---help---
387 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
388 supposed to run on these EM64T-based machines. Only choose this option
389 if you have one of these machines.
390
391 config X86_UV
392 bool "SGI Ultraviolet"
393 depends on X86_64
394 depends on X86_EXTENDED_PLATFORM
395 depends on NUMA
396 depends on X86_X2APIC
397 ---help---
398 This option is needed in order to support SGI Ultraviolet systems.
399 If you don't have one of these, you should say N here.
400
401 # Following is an alphabetically sorted list of 32 bit extended platforms
402 # Please maintain the alphabetic order if and when there are additions
403
404 config X86_INTEL_CE
405 bool "CE4100 TV platform"
406 depends on PCI
407 depends on PCI_GODIRECT
408 depends on X86_32
409 depends on X86_EXTENDED_PLATFORM
410 select X86_REBOOTFIXUPS
411 select OF
412 select OF_EARLY_FLATTREE
413 select IRQ_DOMAIN
414 ---help---
415 Select for the Intel CE media processor (CE4100) SOC.
416 This option compiles in support for the CE4100 SOC for settop
417 boxes and media devices.
418
419 config X86_WANT_INTEL_MID
420 bool "Intel MID platform support"
421 depends on X86_32
422 depends on X86_EXTENDED_PLATFORM
423 ---help---
424 Select to build a kernel capable of supporting Intel MID platform
425 systems which do not have the PCI legacy interfaces (Moorestown,
426 Medfield). If you are building for a PC class system say N here.
427
428 if X86_WANT_INTEL_MID
429
430 config X86_INTEL_MID
431 bool
432
433 config X86_MDFLD
434 bool "Medfield MID platform"
435 depends on PCI
436 depends on PCI_GOANY
437 depends on X86_IO_APIC
438 select X86_INTEL_MID
439 select SFI
440 select DW_APB_TIMER
441 select APB_TIMER
442 select I2C
443 select SPI
444 select INTEL_SCU_IPC
445 select X86_PLATFORM_DEVICES
446 select MFD_INTEL_MSIC
447 ---help---
448 Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin
449 Internet Device(MID) platform.
450 Unlike standard x86 PCs, Medfield does not have many legacy devices
451 nor standard legacy replacement devices/features. e.g. Medfield does
452 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
453
454 endif
455
456 config X86_RDC321X
457 bool "RDC R-321x SoC"
458 depends on X86_32
459 depends on X86_EXTENDED_PLATFORM
460 select M486
461 select X86_REBOOTFIXUPS
462 ---help---
463 This option is needed for RDC R-321x system-on-chip, also known
464 as R-8610-(G).
465 If you don't have one of these chips, you should say N here.
466
467 config X86_32_NON_STANDARD
468 bool "Support non-standard 32-bit SMP architectures"
469 depends on X86_32 && SMP
470 depends on X86_EXTENDED_PLATFORM
471 ---help---
472 This option compiles in the NUMAQ, Summit, bigsmp, ES7000,
473 STA2X11, default subarchitectures. It is intended for a generic
474 binary kernel. If you select them all, kernel will probe it
475 one by one and will fallback to default.
476
477 # Alphabetically sorted list of Non standard 32 bit platforms
478
479 config X86_NUMAQ
480 bool "NUMAQ (IBM/Sequent)"
481 depends on X86_32_NON_STANDARD
482 depends on PCI
483 select NUMA
484 select X86_MPPARSE
485 ---help---
486 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
487 NUMA multiquad box. This changes the way that processors are
488 bootstrapped, and uses Clustered Logical APIC addressing mode instead
489 of Flat Logical. You will need a new lynxer.elf file to flash your
490 firmware with - send email to <Martin.Bligh@us.ibm.com>.
491
492 config X86_SUPPORTS_MEMORY_FAILURE
493 def_bool y
494 # MCE code calls memory_failure():
495 depends on X86_MCE
496 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
497 depends on !X86_NUMAQ
498 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
499 depends on X86_64 || !SPARSEMEM
500 select ARCH_SUPPORTS_MEMORY_FAILURE
501
502 config X86_VISWS
503 bool "SGI 320/540 (Visual Workstation)"
504 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
505 depends on X86_32_NON_STANDARD
506 ---help---
507 The SGI Visual Workstation series is an IA32-based workstation
508 based on SGI systems chips with some legacy PC hardware attached.
509
510 Say Y here to create a kernel to run on the SGI 320 or 540.
511
512 A kernel compiled for the Visual Workstation will run on general
513 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
514
515 config STA2X11
516 bool "STA2X11 Companion Chip Support"
517 depends on X86_32_NON_STANDARD && PCI
518 select X86_DEV_DMA_OPS
519 select X86_DMA_REMAP
520 select SWIOTLB
521 select MFD_STA2X11
522 select ARCH_REQUIRE_GPIOLIB
523 default n
524 ---help---
525 This adds support for boards based on the STA2X11 IO-Hub,
526 a.k.a. "ConneXt". The chip is used in place of the standard
527 PC chipset, so all "standard" peripherals are missing. If this
528 option is selected the kernel will still be able to boot on
529 standard PC machines.
530
531 config X86_SUMMIT
532 bool "Summit/EXA (IBM x440)"
533 depends on X86_32_NON_STANDARD
534 ---help---
535 This option is needed for IBM systems that use the Summit/EXA chipset.
536 In particular, it is needed for the x440.
537
538 config X86_ES7000
539 bool "Unisys ES7000 IA32 series"
540 depends on X86_32_NON_STANDARD && X86_BIGSMP
541 ---help---
542 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
543 supposed to run on an IA32-based Unisys ES7000 system.
544
545 config X86_32_IRIS
546 tristate "Eurobraille/Iris poweroff module"
547 depends on X86_32
548 ---help---
549 The Iris machines from EuroBraille do not have APM or ACPI support
550 to shut themselves down properly. A special I/O sequence is
551 needed to do so, which is what this module does at
552 kernel shutdown.
553
554 This is only for Iris machines from EuroBraille.
555
556 If unused, say N.
557
558 config SCHED_OMIT_FRAME_POINTER
559 def_bool y
560 prompt "Single-depth WCHAN output"
561 depends on X86
562 ---help---
563 Calculate simpler /proc/<PID>/wchan values. If this option
564 is disabled then wchan values will recurse back to the
565 caller function. This provides more accurate wchan values,
566 at the expense of slightly more scheduling overhead.
567
568 If in doubt, say "Y".
569
570 menuconfig PARAVIRT_GUEST
571 bool "Paravirtualized guest support"
572 ---help---
573 Say Y here to get to see options related to running Linux under
574 various hypervisors. This option alone does not add any kernel code.
575
576 If you say N, all options in this submenu will be skipped and disabled.
577
578 if PARAVIRT_GUEST
579
580 config PARAVIRT_TIME_ACCOUNTING
581 bool "Paravirtual steal time accounting"
582 select PARAVIRT
583 default n
584 ---help---
585 Select this option to enable fine granularity task steal time
586 accounting. Time spent executing other tasks in parallel with
587 the current vCPU is discounted from the vCPU power. To account for
588 that, there can be a small performance impact.
589
590 If in doubt, say N here.
591
592 source "arch/x86/xen/Kconfig"
593
594 config KVM_GUEST
595 bool "KVM Guest support (including kvmclock)"
596 select PARAVIRT
597 select PARAVIRT
598 select PARAVIRT_CLOCK
599 default y if PARAVIRT_GUEST
600 ---help---
601 This option enables various optimizations for running under the KVM
602 hypervisor. It includes a paravirtualized clock, so that instead
603 of relying on a PIT (or probably other) emulation by the
604 underlying device model, the host provides the guest with
605 timing infrastructure such as time of day, and system time
606
607 source "arch/x86/lguest/Kconfig"
608
609 config PARAVIRT
610 bool "Enable paravirtualization code"
611 ---help---
612 This changes the kernel so it can modify itself when it is run
613 under a hypervisor, potentially improving performance significantly
614 over full virtualization. However, when run without a hypervisor
615 the kernel is theoretically slower and slightly larger.
616
617 config PARAVIRT_SPINLOCKS
618 bool "Paravirtualization layer for spinlocks"
619 depends on PARAVIRT && SMP && EXPERIMENTAL
620 ---help---
621 Paravirtualized spinlocks allow a pvops backend to replace the
622 spinlock implementation with something virtualization-friendly
623 (for example, block the virtual CPU rather than spinning).
624
625 Unfortunately the downside is an up to 5% performance hit on
626 native kernels, with various workloads.
627
628 If you are unsure how to answer this question, answer N.
629
630 config PARAVIRT_CLOCK
631 bool
632
633 endif
634
635 config PARAVIRT_DEBUG
636 bool "paravirt-ops debugging"
637 depends on PARAVIRT && DEBUG_KERNEL
638 ---help---
639 Enable to debug paravirt_ops internals. Specifically, BUG if
640 a paravirt_op is missing when it is called.
641
642 config NO_BOOTMEM
643 def_bool y
644
645 config MEMTEST
646 bool "Memtest"
647 ---help---
648 This option adds a kernel parameter 'memtest', which allows memtest
649 to be set.
650 memtest=0, mean disabled; -- default
651 memtest=1, mean do 1 test pattern;
652 ...
653 memtest=4, mean do 4 test patterns.
654 If you are unsure how to answer this question, answer N.
655
656 config X86_SUMMIT_NUMA
657 def_bool y
658 depends on X86_32 && NUMA && X86_32_NON_STANDARD
659
660 config X86_CYCLONE_TIMER
661 def_bool y
662 depends on X86_SUMMIT
663
664 source "arch/x86/Kconfig.cpu"
665
666 config HPET_TIMER
667 def_bool X86_64
668 prompt "HPET Timer Support" if X86_32
669 ---help---
670 Use the IA-PC HPET (High Precision Event Timer) to manage
671 time in preference to the PIT and RTC, if a HPET is
672 present.
673 HPET is the next generation timer replacing legacy 8254s.
674 The HPET provides a stable time base on SMP
675 systems, unlike the TSC, but it is more expensive to access,
676 as it is off-chip. You can find the HPET spec at
677 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
678
679 You can safely choose Y here. However, HPET will only be
680 activated if the platform and the BIOS support this feature.
681 Otherwise the 8254 will be used for timing services.
682
683 Choose N to continue using the legacy 8254 timer.
684
685 config HPET_EMULATE_RTC
686 def_bool y
687 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
688
689 config APB_TIMER
690 def_bool y if X86_INTEL_MID
691 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
692 select DW_APB_TIMER
693 depends on X86_INTEL_MID && SFI
694 help
695 APB timer is the replacement for 8254, HPET on X86 MID platforms.
696 The APBT provides a stable time base on SMP
697 systems, unlike the TSC, but it is more expensive to access,
698 as it is off-chip. APB timers are always running regardless of CPU
699 C states, they are used as per CPU clockevent device when possible.
700
701 # Mark as expert because too many people got it wrong.
702 # The code disables itself when not needed.
703 config DMI
704 default y
705 bool "Enable DMI scanning" if EXPERT
706 ---help---
707 Enabled scanning of DMI to identify machine quirks. Say Y
708 here unless you have verified that your setup is not
709 affected by entries in the DMI blacklist. Required by PNP
710 BIOS code.
711
712 config GART_IOMMU
713 bool "GART IOMMU support" if EXPERT
714 default y
715 select SWIOTLB
716 depends on X86_64 && PCI && AMD_NB
717 ---help---
718 Support for full DMA access of devices with 32bit memory access only
719 on systems with more than 3GB. This is usually needed for USB,
720 sound, many IDE/SATA chipsets and some other devices.
721 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
722 based hardware IOMMU and a software bounce buffer based IOMMU used
723 on Intel systems and as fallback.
724 The code is only active when needed (enough memory and limited
725 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
726 too.
727
728 config CALGARY_IOMMU
729 bool "IBM Calgary IOMMU support"
730 select SWIOTLB
731 depends on X86_64 && PCI && EXPERIMENTAL
732 ---help---
733 Support for hardware IOMMUs in IBM's xSeries x366 and x460
734 systems. Needed to run systems with more than 3GB of memory
735 properly with 32-bit PCI devices that do not support DAC
736 (Double Address Cycle). Calgary also supports bus level
737 isolation, where all DMAs pass through the IOMMU. This
738 prevents them from going anywhere except their intended
739 destination. This catches hard-to-find kernel bugs and
740 mis-behaving drivers and devices that do not use the DMA-API
741 properly to set up their DMA buffers. The IOMMU can be
742 turned off at boot time with the iommu=off parameter.
743 Normally the kernel will make the right choice by itself.
744 If unsure, say Y.
745
746 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
747 def_bool y
748 prompt "Should Calgary be enabled by default?"
749 depends on CALGARY_IOMMU
750 ---help---
751 Should Calgary be enabled by default? if you choose 'y', Calgary
752 will be used (if it exists). If you choose 'n', Calgary will not be
753 used even if it exists. If you choose 'n' and would like to use
754 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
755 If unsure, say Y.
756
757 # need this always selected by IOMMU for the VIA workaround
758 config SWIOTLB
759 def_bool y if X86_64
760 ---help---
761 Support for software bounce buffers used on x86-64 systems
762 which don't have a hardware IOMMU. Using this PCI devices
763 which can only access 32-bits of memory can be used on systems
764 with more than 3 GB of memory.
765 If unsure, say Y.
766
767 config IOMMU_HELPER
768 def_bool y
769 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
770
771 config MAXSMP
772 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
773 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
774 select CPUMASK_OFFSTACK
775 ---help---
776 Enable maximum number of CPUS and NUMA Nodes for this architecture.
777 If unsure, say N.
778
779 config NR_CPUS
780 int "Maximum number of CPUs" if SMP && !MAXSMP
781 range 2 8 if SMP && X86_32 && !X86_BIGSMP
782 range 2 512 if SMP && !MAXSMP
783 default "1" if !SMP
784 default "4096" if MAXSMP
785 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
786 default "8" if SMP
787 ---help---
788 This allows you to specify the maximum number of CPUs which this
789 kernel will support. The maximum supported value is 512 and the
790 minimum value which makes sense is 2.
791
792 This is purely to save memory - each supported CPU adds
793 approximately eight kilobytes to the kernel image.
794
795 config SCHED_SMT
796 bool "SMT (Hyperthreading) scheduler support"
797 depends on X86_HT
798 ---help---
799 SMT scheduler support improves the CPU scheduler's decision making
800 when dealing with Intel Pentium 4 chips with HyperThreading at a
801 cost of slightly increased overhead in some places. If unsure say
802 N here.
803
804 config SCHED_MC
805 def_bool y
806 prompt "Multi-core scheduler support"
807 depends on X86_HT
808 ---help---
809 Multi-core scheduler support improves the CPU scheduler's decision
810 making when dealing with multi-core CPU chips at a cost of slightly
811 increased overhead in some places. If unsure say N here.
812
813 source "kernel/Kconfig.preempt"
814
815 config X86_UP_APIC
816 bool "Local APIC support on uniprocessors"
817 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
818 ---help---
819 A local APIC (Advanced Programmable Interrupt Controller) is an
820 integrated interrupt controller in the CPU. If you have a single-CPU
821 system which has a processor with a local APIC, you can say Y here to
822 enable and use it. If you say Y here even though your machine doesn't
823 have a local APIC, then the kernel will still run with no slowdown at
824 all. The local APIC supports CPU-generated self-interrupts (timer,
825 performance counters), and the NMI watchdog which detects hard
826 lockups.
827
828 config X86_UP_IOAPIC
829 bool "IO-APIC support on uniprocessors"
830 depends on X86_UP_APIC
831 ---help---
832 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
833 SMP-capable replacement for PC-style interrupt controllers. Most
834 SMP systems and many recent uniprocessor systems have one.
835
836 If you have a single-CPU system with an IO-APIC, you can say Y here
837 to use it. If you say Y here even though your machine doesn't have
838 an IO-APIC, then the kernel will still run with no slowdown at all.
839
840 config X86_LOCAL_APIC
841 def_bool y
842 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
843
844 config X86_IO_APIC
845 def_bool y
846 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC
847
848 config X86_VISWS_APIC
849 def_bool y
850 depends on X86_32 && X86_VISWS
851
852 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
853 bool "Reroute for broken boot IRQs"
854 depends on X86_IO_APIC
855 ---help---
856 This option enables a workaround that fixes a source of
857 spurious interrupts. This is recommended when threaded
858 interrupt handling is used on systems where the generation of
859 superfluous "boot interrupts" cannot be disabled.
860
861 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
862 entry in the chipset's IO-APIC is masked (as, e.g. the RT
863 kernel does during interrupt handling). On chipsets where this
864 boot IRQ generation cannot be disabled, this workaround keeps
865 the original IRQ line masked so that only the equivalent "boot
866 IRQ" is delivered to the CPUs. The workaround also tells the
867 kernel to set up the IRQ handler on the boot IRQ line. In this
868 way only one interrupt is delivered to the kernel. Otherwise
869 the spurious second interrupt may cause the kernel to bring
870 down (vital) interrupt lines.
871
872 Only affects "broken" chipsets. Interrupt sharing may be
873 increased on these systems.
874
875 config X86_MCE
876 bool "Machine Check / overheating reporting"
877 default y
878 ---help---
879 Machine Check support allows the processor to notify the
880 kernel if it detects a problem (e.g. overheating, data corruption).
881 The action the kernel takes depends on the severity of the problem,
882 ranging from warning messages to halting the machine.
883
884 config X86_MCE_INTEL
885 def_bool y
886 prompt "Intel MCE features"
887 depends on X86_MCE && X86_LOCAL_APIC
888 ---help---
889 Additional support for intel specific MCE features such as
890 the thermal monitor.
891
892 config X86_MCE_AMD
893 def_bool y
894 prompt "AMD MCE features"
895 depends on X86_MCE && X86_LOCAL_APIC
896 ---help---
897 Additional support for AMD specific MCE features such as
898 the DRAM Error Threshold.
899
900 config X86_ANCIENT_MCE
901 bool "Support for old Pentium 5 / WinChip machine checks"
902 depends on X86_32 && X86_MCE
903 ---help---
904 Include support for machine check handling on old Pentium 5 or WinChip
905 systems. These typically need to be enabled explicitely on the command
906 line.
907
908 config X86_MCE_THRESHOLD
909 depends on X86_MCE_AMD || X86_MCE_INTEL
910 def_bool y
911
912 config X86_MCE_INJECT
913 depends on X86_MCE
914 tristate "Machine check injector support"
915 ---help---
916 Provide support for injecting machine checks for testing purposes.
917 If you don't know what a machine check is and you don't do kernel
918 QA it is safe to say n.
919
920 config X86_THERMAL_VECTOR
921 def_bool y
922 depends on X86_MCE_INTEL
923
924 config VM86
925 bool "Enable VM86 support" if EXPERT
926 default y
927 depends on X86_32
928 ---help---
929 This option is required by programs like DOSEMU to run 16-bit legacy
930 code on X86 processors. It also may be needed by software like
931 XFree86 to initialize some video cards via BIOS. Disabling this
932 option saves about 6k.
933
934 config TOSHIBA
935 tristate "Toshiba Laptop support"
936 depends on X86_32
937 ---help---
938 This adds a driver to safely access the System Management Mode of
939 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
940 not work on models with a Phoenix BIOS. The System Management Mode
941 is used to set the BIOS and power saving options on Toshiba portables.
942
943 For information on utilities to make use of this driver see the
944 Toshiba Linux utilities web site at:
945 <http://www.buzzard.org.uk/toshiba/>.
946
947 Say Y if you intend to run this kernel on a Toshiba portable.
948 Say N otherwise.
949
950 config I8K
951 tristate "Dell laptop support"
952 select HWMON
953 ---help---
954 This adds a driver to safely access the System Management Mode
955 of the CPU on the Dell Inspiron 8000. The System Management Mode
956 is used to read cpu temperature and cooling fan status and to
957 control the fans on the I8K portables.
958
959 This driver has been tested only on the Inspiron 8000 but it may
960 also work with other Dell laptops. You can force loading on other
961 models by passing the parameter `force=1' to the module. Use at
962 your own risk.
963
964 For information on utilities to make use of this driver see the
965 I8K Linux utilities web site at:
966 <http://people.debian.org/~dz/i8k/>
967
968 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
969 Say N otherwise.
970
971 config X86_REBOOTFIXUPS
972 bool "Enable X86 board specific fixups for reboot"
973 depends on X86_32
974 ---help---
975 This enables chipset and/or board specific fixups to be done
976 in order to get reboot to work correctly. This is only needed on
977 some combinations of hardware and BIOS. The symptom, for which
978 this config is intended, is when reboot ends with a stalled/hung
979 system.
980
981 Currently, the only fixup is for the Geode machines using
982 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
983
984 Say Y if you want to enable the fixup. Currently, it's safe to
985 enable this option even if you don't need it.
986 Say N otherwise.
987
988 config MICROCODE
989 tristate "CPU microcode loading support"
990 select FW_LOADER
991 ---help---
992
993 If you say Y here, you will be able to update the microcode on
994 certain Intel and AMD processors. The Intel support is for the
995 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
996 Xeon etc. The AMD support is for families 0x10 and later. You will
997 obviously need the actual microcode binary data itself which is not
998 shipped with the Linux kernel.
999
1000 This option selects the general module only, you need to select
1001 at least one vendor specific module as well.
1002
1003 To compile this driver as a module, choose M here: the module
1004 will be called microcode.
1005
1006 config MICROCODE_INTEL
1007 bool "Intel microcode loading support"
1008 depends on MICROCODE
1009 default MICROCODE
1010 select FW_LOADER
1011 ---help---
1012 This options enables microcode patch loading support for Intel
1013 processors.
1014
1015 For latest news and information on obtaining all the required
1016 Intel ingredients for this driver, check:
1017 <http://www.urbanmyth.org/microcode/>.
1018
1019 config MICROCODE_AMD
1020 bool "AMD microcode loading support"
1021 depends on MICROCODE
1022 select FW_LOADER
1023 ---help---
1024 If you select this option, microcode patch loading support for AMD
1025 processors will be enabled.
1026
1027 config MICROCODE_OLD_INTERFACE
1028 def_bool y
1029 depends on MICROCODE
1030
1031 config X86_MSR
1032 tristate "/dev/cpu/*/msr - Model-specific register support"
1033 ---help---
1034 This device gives privileged processes access to the x86
1035 Model-Specific Registers (MSRs). It is a character device with
1036 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1037 MSR accesses are directed to a specific CPU on multi-processor
1038 systems.
1039
1040 config X86_CPUID
1041 tristate "/dev/cpu/*/cpuid - CPU information support"
1042 ---help---
1043 This device gives processes access to the x86 CPUID instruction to
1044 be executed on a specific processor. It is a character device
1045 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1046 /dev/cpu/31/cpuid.
1047
1048 choice
1049 prompt "High Memory Support"
1050 default HIGHMEM64G if X86_NUMAQ
1051 default HIGHMEM4G
1052 depends on X86_32
1053
1054 config NOHIGHMEM
1055 bool "off"
1056 depends on !X86_NUMAQ
1057 ---help---
1058 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1059 However, the address space of 32-bit x86 processors is only 4
1060 Gigabytes large. That means that, if you have a large amount of
1061 physical memory, not all of it can be "permanently mapped" by the
1062 kernel. The physical memory that's not permanently mapped is called
1063 "high memory".
1064
1065 If you are compiling a kernel which will never run on a machine with
1066 more than 1 Gigabyte total physical RAM, answer "off" here (default
1067 choice and suitable for most users). This will result in a "3GB/1GB"
1068 split: 3GB are mapped so that each process sees a 3GB virtual memory
1069 space and the remaining part of the 4GB virtual memory space is used
1070 by the kernel to permanently map as much physical memory as
1071 possible.
1072
1073 If the machine has between 1 and 4 Gigabytes physical RAM, then
1074 answer "4GB" here.
1075
1076 If more than 4 Gigabytes is used then answer "64GB" here. This
1077 selection turns Intel PAE (Physical Address Extension) mode on.
1078 PAE implements 3-level paging on IA32 processors. PAE is fully
1079 supported by Linux, PAE mode is implemented on all recent Intel
1080 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1081 then the kernel will not boot on CPUs that don't support PAE!
1082
1083 The actual amount of total physical memory will either be
1084 auto detected or can be forced by using a kernel command line option
1085 such as "mem=256M". (Try "man bootparam" or see the documentation of
1086 your boot loader (lilo or loadlin) about how to pass options to the
1087 kernel at boot time.)
1088
1089 If unsure, say "off".
1090
1091 config HIGHMEM4G
1092 bool "4GB"
1093 depends on !X86_NUMAQ
1094 ---help---
1095 Select this if you have a 32-bit processor and between 1 and 4
1096 gigabytes of physical RAM.
1097
1098 config HIGHMEM64G
1099 bool "64GB"
1100 depends on !M386 && !M486
1101 select X86_PAE
1102 ---help---
1103 Select this if you have a 32-bit processor and more than 4
1104 gigabytes of physical RAM.
1105
1106 endchoice
1107
1108 choice
1109 depends on EXPERIMENTAL
1110 prompt "Memory split" if EXPERT
1111 default VMSPLIT_3G
1112 depends on X86_32
1113 ---help---
1114 Select the desired split between kernel and user memory.
1115
1116 If the address range available to the kernel is less than the
1117 physical memory installed, the remaining memory will be available
1118 as "high memory". Accessing high memory is a little more costly
1119 than low memory, as it needs to be mapped into the kernel first.
1120 Note that increasing the kernel address space limits the range
1121 available to user programs, making the address space there
1122 tighter. Selecting anything other than the default 3G/1G split
1123 will also likely make your kernel incompatible with binary-only
1124 kernel modules.
1125
1126 If you are not absolutely sure what you are doing, leave this
1127 option alone!
1128
1129 config VMSPLIT_3G
1130 bool "3G/1G user/kernel split"
1131 config VMSPLIT_3G_OPT
1132 depends on !X86_PAE
1133 bool "3G/1G user/kernel split (for full 1G low memory)"
1134 config VMSPLIT_2G
1135 bool "2G/2G user/kernel split"
1136 config VMSPLIT_2G_OPT
1137 depends on !X86_PAE
1138 bool "2G/2G user/kernel split (for full 2G low memory)"
1139 config VMSPLIT_1G
1140 bool "1G/3G user/kernel split"
1141 endchoice
1142
1143 config PAGE_OFFSET
1144 hex
1145 default 0xB0000000 if VMSPLIT_3G_OPT
1146 default 0x80000000 if VMSPLIT_2G
1147 default 0x78000000 if VMSPLIT_2G_OPT
1148 default 0x40000000 if VMSPLIT_1G
1149 default 0xC0000000
1150 depends on X86_32
1151
1152 config HIGHMEM
1153 def_bool y
1154 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1155
1156 config X86_PAE
1157 bool "PAE (Physical Address Extension) Support"
1158 depends on X86_32 && !HIGHMEM4G
1159 ---help---
1160 PAE is required for NX support, and furthermore enables
1161 larger swapspace support for non-overcommit purposes. It
1162 has the cost of more pagetable lookup overhead, and also
1163 consumes more pagetable space per process.
1164
1165 config ARCH_PHYS_ADDR_T_64BIT
1166 def_bool y
1167 depends on X86_64 || X86_PAE
1168
1169 config ARCH_DMA_ADDR_T_64BIT
1170 def_bool y
1171 depends on X86_64 || HIGHMEM64G
1172
1173 config DIRECT_GBPAGES
1174 bool "Enable 1GB pages for kernel pagetables" if EXPERT
1175 default y
1176 depends on X86_64
1177 ---help---
1178 Allow the kernel linear mapping to use 1GB pages on CPUs that
1179 support it. This can improve the kernel's performance a tiny bit by
1180 reducing TLB pressure. If in doubt, say "Y".
1181
1182 # Common NUMA Features
1183 config NUMA
1184 bool "Numa Memory Allocation and Scheduler Support"
1185 depends on SMP
1186 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1187 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1188 ---help---
1189 Enable NUMA (Non Uniform Memory Access) support.
1190
1191 The kernel will try to allocate memory used by a CPU on the
1192 local memory controller of the CPU and add some more
1193 NUMA awareness to the kernel.
1194
1195 For 64-bit this is recommended if the system is Intel Core i7
1196 (or later), AMD Opteron, or EM64T NUMA.
1197
1198 For 32-bit this is only needed on (rare) 32-bit-only platforms
1199 that support NUMA topologies, such as NUMAQ / Summit, or if you
1200 boot a 32-bit kernel on a 64-bit NUMA platform.
1201
1202 Otherwise, you should say N.
1203
1204 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1205 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1206
1207 config AMD_NUMA
1208 def_bool y
1209 prompt "Old style AMD Opteron NUMA detection"
1210 depends on X86_64 && NUMA && PCI
1211 ---help---
1212 Enable AMD NUMA node topology detection. You should say Y here if
1213 you have a multi processor AMD system. This uses an old method to
1214 read the NUMA configuration directly from the builtin Northbridge
1215 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1216 which also takes priority if both are compiled in.
1217
1218 config X86_64_ACPI_NUMA
1219 def_bool y
1220 prompt "ACPI NUMA detection"
1221 depends on X86_64 && NUMA && ACPI && PCI
1222 select ACPI_NUMA
1223 ---help---
1224 Enable ACPI SRAT based node topology detection.
1225
1226 # Some NUMA nodes have memory ranges that span
1227 # other nodes. Even though a pfn is valid and
1228 # between a node's start and end pfns, it may not
1229 # reside on that node. See memmap_init_zone()
1230 # for details.
1231 config NODES_SPAN_OTHER_NODES
1232 def_bool y
1233 depends on X86_64_ACPI_NUMA
1234
1235 config NUMA_EMU
1236 bool "NUMA emulation"
1237 depends on NUMA
1238 ---help---
1239 Enable NUMA emulation. A flat machine will be split
1240 into virtual nodes when booted with "numa=fake=N", where N is the
1241 number of nodes. This is only useful for debugging.
1242
1243 config NODES_SHIFT
1244 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1245 range 1 10
1246 default "10" if MAXSMP
1247 default "6" if X86_64
1248 default "4" if X86_NUMAQ
1249 default "3"
1250 depends on NEED_MULTIPLE_NODES
1251 ---help---
1252 Specify the maximum number of NUMA Nodes available on the target
1253 system. Increases memory reserved to accommodate various tables.
1254
1255 config HAVE_ARCH_ALLOC_REMAP
1256 def_bool y
1257 depends on X86_32 && NUMA
1258
1259 config ARCH_HAVE_MEMORY_PRESENT
1260 def_bool y
1261 depends on X86_32 && DISCONTIGMEM
1262
1263 config NEED_NODE_MEMMAP_SIZE
1264 def_bool y
1265 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1266
1267 config ARCH_FLATMEM_ENABLE
1268 def_bool y
1269 depends on X86_32 && !NUMA
1270
1271 config ARCH_DISCONTIGMEM_ENABLE
1272 def_bool y
1273 depends on NUMA && X86_32
1274
1275 config ARCH_DISCONTIGMEM_DEFAULT
1276 def_bool y
1277 depends on NUMA && X86_32
1278
1279 config ARCH_SPARSEMEM_ENABLE
1280 def_bool y
1281 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1282 select SPARSEMEM_STATIC if X86_32
1283 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1284
1285 config ARCH_SPARSEMEM_DEFAULT
1286 def_bool y
1287 depends on X86_64
1288
1289 config ARCH_SELECT_MEMORY_MODEL
1290 def_bool y
1291 depends on ARCH_SPARSEMEM_ENABLE
1292
1293 config ARCH_MEMORY_PROBE
1294 def_bool y
1295 depends on X86_64 && MEMORY_HOTPLUG
1296
1297 config ARCH_PROC_KCORE_TEXT
1298 def_bool y
1299 depends on X86_64 && PROC_KCORE
1300
1301 config ILLEGAL_POINTER_VALUE
1302 hex
1303 default 0 if X86_32
1304 default 0xdead000000000000 if X86_64
1305
1306 source "mm/Kconfig"
1307
1308 config HIGHPTE
1309 bool "Allocate 3rd-level pagetables from highmem"
1310 depends on HIGHMEM
1311 ---help---
1312 The VM uses one page table entry for each page of physical memory.
1313 For systems with a lot of RAM, this can be wasteful of precious
1314 low memory. Setting this option will put user-space page table
1315 entries in high memory.
1316
1317 config X86_CHECK_BIOS_CORRUPTION
1318 bool "Check for low memory corruption"
1319 ---help---
1320 Periodically check for memory corruption in low memory, which
1321 is suspected to be caused by BIOS. Even when enabled in the
1322 configuration, it is disabled at runtime. Enable it by
1323 setting "memory_corruption_check=1" on the kernel command
1324 line. By default it scans the low 64k of memory every 60
1325 seconds; see the memory_corruption_check_size and
1326 memory_corruption_check_period parameters in
1327 Documentation/kernel-parameters.txt to adjust this.
1328
1329 When enabled with the default parameters, this option has
1330 almost no overhead, as it reserves a relatively small amount
1331 of memory and scans it infrequently. It both detects corruption
1332 and prevents it from affecting the running system.
1333
1334 It is, however, intended as a diagnostic tool; if repeatable
1335 BIOS-originated corruption always affects the same memory,
1336 you can use memmap= to prevent the kernel from using that
1337 memory.
1338
1339 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1340 bool "Set the default setting of memory_corruption_check"
1341 depends on X86_CHECK_BIOS_CORRUPTION
1342 default y
1343 ---help---
1344 Set whether the default state of memory_corruption_check is
1345 on or off.
1346
1347 config X86_RESERVE_LOW
1348 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1349 default 64
1350 range 4 640
1351 ---help---
1352 Specify the amount of low memory to reserve for the BIOS.
1353
1354 The first page contains BIOS data structures that the kernel
1355 must not use, so that page must always be reserved.
1356
1357 By default we reserve the first 64K of physical RAM, as a
1358 number of BIOSes are known to corrupt that memory range
1359 during events such as suspend/resume or monitor cable
1360 insertion, so it must not be used by the kernel.
1361
1362 You can set this to 4 if you are absolutely sure that you
1363 trust the BIOS to get all its memory reservations and usages
1364 right. If you know your BIOS have problems beyond the
1365 default 64K area, you can set this to 640 to avoid using the
1366 entire low memory range.
1367
1368 If you have doubts about the BIOS (e.g. suspend/resume does
1369 not work or there's kernel crashes after certain hardware
1370 hotplug events) then you might want to enable
1371 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1372 typical corruption patterns.
1373
1374 Leave this to the default value of 64 if you are unsure.
1375
1376 config MATH_EMULATION
1377 bool
1378 prompt "Math emulation" if X86_32
1379 ---help---
1380 Linux can emulate a math coprocessor (used for floating point
1381 operations) if you don't have one. 486DX and Pentium processors have
1382 a math coprocessor built in, 486SX and 386 do not, unless you added
1383 a 487DX or 387, respectively. (The messages during boot time can
1384 give you some hints here ["man dmesg"].) Everyone needs either a
1385 coprocessor or this emulation.
1386
1387 If you don't have a math coprocessor, you need to say Y here; if you
1388 say Y here even though you have a coprocessor, the coprocessor will
1389 be used nevertheless. (This behavior can be changed with the kernel
1390 command line option "no387", which comes handy if your coprocessor
1391 is broken. Try "man bootparam" or see the documentation of your boot
1392 loader (lilo or loadlin) about how to pass options to the kernel at
1393 boot time.) This means that it is a good idea to say Y here if you
1394 intend to use this kernel on different machines.
1395
1396 More information about the internals of the Linux math coprocessor
1397 emulation can be found in <file:arch/x86/math-emu/README>.
1398
1399 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1400 kernel, it won't hurt.
1401
1402 config MTRR
1403 def_bool y
1404 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1405 ---help---
1406 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1407 the Memory Type Range Registers (MTRRs) may be used to control
1408 processor access to memory ranges. This is most useful if you have
1409 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1410 allows bus write transfers to be combined into a larger transfer
1411 before bursting over the PCI/AGP bus. This can increase performance
1412 of image write operations 2.5 times or more. Saying Y here creates a
1413 /proc/mtrr file which may be used to manipulate your processor's
1414 MTRRs. Typically the X server should use this.
1415
1416 This code has a reasonably generic interface so that similar
1417 control registers on other processors can be easily supported
1418 as well:
1419
1420 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1421 Registers (ARRs) which provide a similar functionality to MTRRs. For
1422 these, the ARRs are used to emulate the MTRRs.
1423 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1424 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1425 write-combining. All of these processors are supported by this code
1426 and it makes sense to say Y here if you have one of them.
1427
1428 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1429 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1430 can lead to all sorts of problems, so it's good to say Y here.
1431
1432 You can safely say Y even if your machine doesn't have MTRRs, you'll
1433 just add about 9 KB to your kernel.
1434
1435 See <file:Documentation/x86/mtrr.txt> for more information.
1436
1437 config MTRR_SANITIZER
1438 def_bool y
1439 prompt "MTRR cleanup support"
1440 depends on MTRR
1441 ---help---
1442 Convert MTRR layout from continuous to discrete, so X drivers can
1443 add writeback entries.
1444
1445 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1446 The largest mtrr entry size for a continuous block can be set with
1447 mtrr_chunk_size.
1448
1449 If unsure, say Y.
1450
1451 config MTRR_SANITIZER_ENABLE_DEFAULT
1452 int "MTRR cleanup enable value (0-1)"
1453 range 0 1
1454 default "0"
1455 depends on MTRR_SANITIZER
1456 ---help---
1457 Enable mtrr cleanup default value
1458
1459 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1460 int "MTRR cleanup spare reg num (0-7)"
1461 range 0 7
1462 default "1"
1463 depends on MTRR_SANITIZER
1464 ---help---
1465 mtrr cleanup spare entries default, it can be changed via
1466 mtrr_spare_reg_nr=N on the kernel command line.
1467
1468 config X86_PAT
1469 def_bool y
1470 prompt "x86 PAT support" if EXPERT
1471 depends on MTRR
1472 ---help---
1473 Use PAT attributes to setup page level cache control.
1474
1475 PATs are the modern equivalents of MTRRs and are much more
1476 flexible than MTRRs.
1477
1478 Say N here if you see bootup problems (boot crash, boot hang,
1479 spontaneous reboots) or a non-working video driver.
1480
1481 If unsure, say Y.
1482
1483 config ARCH_USES_PG_UNCACHED
1484 def_bool y
1485 depends on X86_PAT
1486
1487 config ARCH_RANDOM
1488 def_bool y
1489 prompt "x86 architectural random number generator" if EXPERT
1490 ---help---
1491 Enable the x86 architectural RDRAND instruction
1492 (Intel Bull Mountain technology) to generate random numbers.
1493 If supported, this is a high bandwidth, cryptographically
1494 secure hardware random number generator.
1495
1496 config X86_SMAP
1497 def_bool y
1498 prompt "Supervisor Mode Access Prevention" if EXPERT
1499 ---help---
1500 Supervisor Mode Access Prevention (SMAP) is a security
1501 feature in newer Intel processors. There is a small
1502 performance cost if this enabled and turned on; there is
1503 also a small increase in the kernel size if this is enabled.
1504
1505 If unsure, say Y.
1506
1507 config EFI
1508 bool "EFI runtime service support"
1509 depends on ACPI
1510 ---help---
1511 This enables the kernel to use EFI runtime services that are
1512 available (such as the EFI variable services).
1513
1514 This option is only useful on systems that have EFI firmware.
1515 In addition, you should use the latest ELILO loader available
1516 at <http://elilo.sourceforge.net> in order to take advantage
1517 of EFI runtime services. However, even with this option, the
1518 resultant kernel should continue to boot on existing non-EFI
1519 platforms.
1520
1521 config EFI_STUB
1522 bool "EFI stub support"
1523 depends on EFI
1524 ---help---
1525 This kernel feature allows a bzImage to be loaded directly
1526 by EFI firmware without the use of a bootloader.
1527
1528 See Documentation/x86/efi-stub.txt for more information.
1529
1530 config SECCOMP
1531 def_bool y
1532 prompt "Enable seccomp to safely compute untrusted bytecode"
1533 ---help---
1534 This kernel feature is useful for number crunching applications
1535 that may need to compute untrusted bytecode during their
1536 execution. By using pipes or other transports made available to
1537 the process as file descriptors supporting the read/write
1538 syscalls, it's possible to isolate those applications in
1539 their own address space using seccomp. Once seccomp is
1540 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1541 and the task is only allowed to execute a few safe syscalls
1542 defined by each seccomp mode.
1543
1544 If unsure, say Y. Only embedded should say N here.
1545
1546 config CC_STACKPROTECTOR
1547 bool "Enable -fstack-protector buffer overflow detection"
1548 ---help---
1549 This option turns on the -fstack-protector GCC feature. This
1550 feature puts, at the beginning of functions, a canary value on
1551 the stack just before the return address, and validates
1552 the value just before actually returning. Stack based buffer
1553 overflows (that need to overwrite this return address) now also
1554 overwrite the canary, which gets detected and the attack is then
1555 neutralized via a kernel panic.
1556
1557 This feature requires gcc version 4.2 or above, or a distribution
1558 gcc with the feature backported. Older versions are automatically
1559 detected and for those versions, this configuration option is
1560 ignored. (and a warning is printed during bootup)
1561
1562 source kernel/Kconfig.hz
1563
1564 config KEXEC
1565 bool "kexec system call"
1566 ---help---
1567 kexec is a system call that implements the ability to shutdown your
1568 current kernel, and to start another kernel. It is like a reboot
1569 but it is independent of the system firmware. And like a reboot
1570 you can start any kernel with it, not just Linux.
1571
1572 The name comes from the similarity to the exec system call.
1573
1574 It is an ongoing process to be certain the hardware in a machine
1575 is properly shutdown, so do not be surprised if this code does not
1576 initially work for you. It may help to enable device hotplugging
1577 support. As of this writing the exact hardware interface is
1578 strongly in flux, so no good recommendation can be made.
1579
1580 config CRASH_DUMP
1581 bool "kernel crash dumps"
1582 depends on X86_64 || (X86_32 && HIGHMEM)
1583 ---help---
1584 Generate crash dump after being started by kexec.
1585 This should be normally only set in special crash dump kernels
1586 which are loaded in the main kernel with kexec-tools into
1587 a specially reserved region and then later executed after
1588 a crash by kdump/kexec. The crash dump kernel must be compiled
1589 to a memory address not used by the main kernel or BIOS using
1590 PHYSICAL_START, or it must be built as a relocatable image
1591 (CONFIG_RELOCATABLE=y).
1592 For more details see Documentation/kdump/kdump.txt
1593
1594 config KEXEC_JUMP
1595 bool "kexec jump (EXPERIMENTAL)"
1596 depends on EXPERIMENTAL
1597 depends on KEXEC && HIBERNATION
1598 ---help---
1599 Jump between original kernel and kexeced kernel and invoke
1600 code in physical address mode via KEXEC
1601
1602 config PHYSICAL_START
1603 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1604 default "0x1000000"
1605 ---help---
1606 This gives the physical address where the kernel is loaded.
1607
1608 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1609 bzImage will decompress itself to above physical address and
1610 run from there. Otherwise, bzImage will run from the address where
1611 it has been loaded by the boot loader and will ignore above physical
1612 address.
1613
1614 In normal kdump cases one does not have to set/change this option
1615 as now bzImage can be compiled as a completely relocatable image
1616 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1617 address. This option is mainly useful for the folks who don't want
1618 to use a bzImage for capturing the crash dump and want to use a
1619 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1620 to be specifically compiled to run from a specific memory area
1621 (normally a reserved region) and this option comes handy.
1622
1623 So if you are using bzImage for capturing the crash dump,
1624 leave the value here unchanged to 0x1000000 and set
1625 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1626 for capturing the crash dump change this value to start of
1627 the reserved region. In other words, it can be set based on
1628 the "X" value as specified in the "crashkernel=YM@XM"
1629 command line boot parameter passed to the panic-ed
1630 kernel. Please take a look at Documentation/kdump/kdump.txt
1631 for more details about crash dumps.
1632
1633 Usage of bzImage for capturing the crash dump is recommended as
1634 one does not have to build two kernels. Same kernel can be used
1635 as production kernel and capture kernel. Above option should have
1636 gone away after relocatable bzImage support is introduced. But it
1637 is present because there are users out there who continue to use
1638 vmlinux for dump capture. This option should go away down the
1639 line.
1640
1641 Don't change this unless you know what you are doing.
1642
1643 config RELOCATABLE
1644 bool "Build a relocatable kernel"
1645 default y
1646 ---help---
1647 This builds a kernel image that retains relocation information
1648 so it can be loaded someplace besides the default 1MB.
1649 The relocations tend to make the kernel binary about 10% larger,
1650 but are discarded at runtime.
1651
1652 One use is for the kexec on panic case where the recovery kernel
1653 must live at a different physical address than the primary
1654 kernel.
1655
1656 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1657 it has been loaded at and the compile time physical address
1658 (CONFIG_PHYSICAL_START) is ignored.
1659
1660 # Relocation on x86-32 needs some additional build support
1661 config X86_NEED_RELOCS
1662 def_bool y
1663 depends on X86_32 && RELOCATABLE
1664
1665 config PHYSICAL_ALIGN
1666 hex "Alignment value to which kernel should be aligned" if X86_32
1667 default "0x1000000"
1668 range 0x2000 0x1000000
1669 ---help---
1670 This value puts the alignment restrictions on physical address
1671 where kernel is loaded and run from. Kernel is compiled for an
1672 address which meets above alignment restriction.
1673
1674 If bootloader loads the kernel at a non-aligned address and
1675 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1676 address aligned to above value and run from there.
1677
1678 If bootloader loads the kernel at a non-aligned address and
1679 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1680 load address and decompress itself to the address it has been
1681 compiled for and run from there. The address for which kernel is
1682 compiled already meets above alignment restrictions. Hence the
1683 end result is that kernel runs from a physical address meeting
1684 above alignment restrictions.
1685
1686 Don't change this unless you know what you are doing.
1687
1688 config HOTPLUG_CPU
1689 bool "Support for hot-pluggable CPUs"
1690 depends on SMP && HOTPLUG
1691 ---help---
1692 Say Y here to allow turning CPUs off and on. CPUs can be
1693 controlled through /sys/devices/system/cpu.
1694 ( Note: power management support will enable this option
1695 automatically on SMP systems. )
1696 Say N if you want to disable CPU hotplug.
1697
1698 config COMPAT_VDSO
1699 def_bool y
1700 prompt "Compat VDSO support"
1701 depends on X86_32 || IA32_EMULATION
1702 ---help---
1703 Map the 32-bit VDSO to the predictable old-style address too.
1704
1705 Say N here if you are running a sufficiently recent glibc
1706 version (2.3.3 or later), to remove the high-mapped
1707 VDSO mapping and to exclusively use the randomized VDSO.
1708
1709 If unsure, say Y.
1710
1711 config CMDLINE_BOOL
1712 bool "Built-in kernel command line"
1713 ---help---
1714 Allow for specifying boot arguments to the kernel at
1715 build time. On some systems (e.g. embedded ones), it is
1716 necessary or convenient to provide some or all of the
1717 kernel boot arguments with the kernel itself (that is,
1718 to not rely on the boot loader to provide them.)
1719
1720 To compile command line arguments into the kernel,
1721 set this option to 'Y', then fill in the
1722 the boot arguments in CONFIG_CMDLINE.
1723
1724 Systems with fully functional boot loaders (i.e. non-embedded)
1725 should leave this option set to 'N'.
1726
1727 config CMDLINE
1728 string "Built-in kernel command string"
1729 depends on CMDLINE_BOOL
1730 default ""
1731 ---help---
1732 Enter arguments here that should be compiled into the kernel
1733 image and used at boot time. If the boot loader provides a
1734 command line at boot time, it is appended to this string to
1735 form the full kernel command line, when the system boots.
1736
1737 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1738 change this behavior.
1739
1740 In most cases, the command line (whether built-in or provided
1741 by the boot loader) should specify the device for the root
1742 file system.
1743
1744 config CMDLINE_OVERRIDE
1745 bool "Built-in command line overrides boot loader arguments"
1746 depends on CMDLINE_BOOL
1747 ---help---
1748 Set this option to 'Y' to have the kernel ignore the boot loader
1749 command line, and use ONLY the built-in command line.
1750
1751 This is used to work around broken boot loaders. This should
1752 be set to 'N' under normal conditions.
1753
1754 endmenu
1755
1756 config ARCH_ENABLE_MEMORY_HOTPLUG
1757 def_bool y
1758 depends on X86_64 || (X86_32 && HIGHMEM)
1759
1760 config ARCH_ENABLE_MEMORY_HOTREMOVE
1761 def_bool y
1762 depends on MEMORY_HOTPLUG
1763
1764 config USE_PERCPU_NUMA_NODE_ID
1765 def_bool y
1766 depends on NUMA
1767
1768 menu "Power management and ACPI options"
1769
1770 config ARCH_HIBERNATION_HEADER
1771 def_bool y
1772 depends on X86_64 && HIBERNATION
1773
1774 source "kernel/power/Kconfig"
1775
1776 source "drivers/acpi/Kconfig"
1777
1778 source "drivers/sfi/Kconfig"
1779
1780 config X86_APM_BOOT
1781 def_bool y
1782 depends on APM
1783
1784 menuconfig APM
1785 tristate "APM (Advanced Power Management) BIOS support"
1786 depends on X86_32 && PM_SLEEP
1787 ---help---
1788 APM is a BIOS specification for saving power using several different
1789 techniques. This is mostly useful for battery powered laptops with
1790 APM compliant BIOSes. If you say Y here, the system time will be
1791 reset after a RESUME operation, the /proc/apm device will provide
1792 battery status information, and user-space programs will receive
1793 notification of APM "events" (e.g. battery status change).
1794
1795 If you select "Y" here, you can disable actual use of the APM
1796 BIOS by passing the "apm=off" option to the kernel at boot time.
1797
1798 Note that the APM support is almost completely disabled for
1799 machines with more than one CPU.
1800
1801 In order to use APM, you will need supporting software. For location
1802 and more information, read <file:Documentation/power/apm-acpi.txt>
1803 and the Battery Powered Linux mini-HOWTO, available from
1804 <http://www.tldp.org/docs.html#howto>.
1805
1806 This driver does not spin down disk drives (see the hdparm(8)
1807 manpage ("man 8 hdparm") for that), and it doesn't turn off
1808 VESA-compliant "green" monitors.
1809
1810 This driver does not support the TI 4000M TravelMate and the ACER
1811 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1812 desktop machines also don't have compliant BIOSes, and this driver
1813 may cause those machines to panic during the boot phase.
1814
1815 Generally, if you don't have a battery in your machine, there isn't
1816 much point in using this driver and you should say N. If you get
1817 random kernel OOPSes or reboots that don't seem to be related to
1818 anything, try disabling/enabling this option (or disabling/enabling
1819 APM in your BIOS).
1820
1821 Some other things you should try when experiencing seemingly random,
1822 "weird" problems:
1823
1824 1) make sure that you have enough swap space and that it is
1825 enabled.
1826 2) pass the "no-hlt" option to the kernel
1827 3) switch on floating point emulation in the kernel and pass
1828 the "no387" option to the kernel
1829 4) pass the "floppy=nodma" option to the kernel
1830 5) pass the "mem=4M" option to the kernel (thereby disabling
1831 all but the first 4 MB of RAM)
1832 6) make sure that the CPU is not over clocked.
1833 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1834 8) disable the cache from your BIOS settings
1835 9) install a fan for the video card or exchange video RAM
1836 10) install a better fan for the CPU
1837 11) exchange RAM chips
1838 12) exchange the motherboard.
1839
1840 To compile this driver as a module, choose M here: the
1841 module will be called apm.
1842
1843 if APM
1844
1845 config APM_IGNORE_USER_SUSPEND
1846 bool "Ignore USER SUSPEND"
1847 ---help---
1848 This option will ignore USER SUSPEND requests. On machines with a
1849 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1850 series notebooks, it is necessary to say Y because of a BIOS bug.
1851
1852 config APM_DO_ENABLE
1853 bool "Enable PM at boot time"
1854 ---help---
1855 Enable APM features at boot time. From page 36 of the APM BIOS
1856 specification: "When disabled, the APM BIOS does not automatically
1857 power manage devices, enter the Standby State, enter the Suspend
1858 State, or take power saving steps in response to CPU Idle calls."
1859 This driver will make CPU Idle calls when Linux is idle (unless this
1860 feature is turned off -- see "Do CPU IDLE calls", below). This
1861 should always save battery power, but more complicated APM features
1862 will be dependent on your BIOS implementation. You may need to turn
1863 this option off if your computer hangs at boot time when using APM
1864 support, or if it beeps continuously instead of suspending. Turn
1865 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1866 T400CDT. This is off by default since most machines do fine without
1867 this feature.
1868
1869 config APM_CPU_IDLE
1870 bool "Make CPU Idle calls when idle"
1871 ---help---
1872 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1873 On some machines, this can activate improved power savings, such as
1874 a slowed CPU clock rate, when the machine is idle. These idle calls
1875 are made after the idle loop has run for some length of time (e.g.,
1876 333 mS). On some machines, this will cause a hang at boot time or
1877 whenever the CPU becomes idle. (On machines with more than one CPU,
1878 this option does nothing.)
1879
1880 config APM_DISPLAY_BLANK
1881 bool "Enable console blanking using APM"
1882 ---help---
1883 Enable console blanking using the APM. Some laptops can use this to
1884 turn off the LCD backlight when the screen blanker of the Linux
1885 virtual console blanks the screen. Note that this is only used by
1886 the virtual console screen blanker, and won't turn off the backlight
1887 when using the X Window system. This also doesn't have anything to
1888 do with your VESA-compliant power-saving monitor. Further, this
1889 option doesn't work for all laptops -- it might not turn off your
1890 backlight at all, or it might print a lot of errors to the console,
1891 especially if you are using gpm.
1892
1893 config APM_ALLOW_INTS
1894 bool "Allow interrupts during APM BIOS calls"
1895 ---help---
1896 Normally we disable external interrupts while we are making calls to
1897 the APM BIOS as a measure to lessen the effects of a badly behaving
1898 BIOS implementation. The BIOS should reenable interrupts if it
1899 needs to. Unfortunately, some BIOSes do not -- especially those in
1900 many of the newer IBM Thinkpads. If you experience hangs when you
1901 suspend, try setting this to Y. Otherwise, say N.
1902
1903 endif # APM
1904
1905 source "drivers/cpufreq/Kconfig"
1906
1907 source "drivers/cpuidle/Kconfig"
1908
1909 source "drivers/idle/Kconfig"
1910
1911 endmenu
1912
1913
1914 menu "Bus options (PCI etc.)"
1915
1916 config PCI
1917 bool "PCI support"
1918 default y
1919 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1920 ---help---
1921 Find out whether you have a PCI motherboard. PCI is the name of a
1922 bus system, i.e. the way the CPU talks to the other stuff inside
1923 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1924 VESA. If you have PCI, say Y, otherwise N.
1925
1926 choice
1927 prompt "PCI access mode"
1928 depends on X86_32 && PCI
1929 default PCI_GOANY
1930 ---help---
1931 On PCI systems, the BIOS can be used to detect the PCI devices and
1932 determine their configuration. However, some old PCI motherboards
1933 have BIOS bugs and may crash if this is done. Also, some embedded
1934 PCI-based systems don't have any BIOS at all. Linux can also try to
1935 detect the PCI hardware directly without using the BIOS.
1936
1937 With this option, you can specify how Linux should detect the
1938 PCI devices. If you choose "BIOS", the BIOS will be used,
1939 if you choose "Direct", the BIOS won't be used, and if you
1940 choose "MMConfig", then PCI Express MMCONFIG will be used.
1941 If you choose "Any", the kernel will try MMCONFIG, then the
1942 direct access method and falls back to the BIOS if that doesn't
1943 work. If unsure, go with the default, which is "Any".
1944
1945 config PCI_GOBIOS
1946 bool "BIOS"
1947
1948 config PCI_GOMMCONFIG
1949 bool "MMConfig"
1950
1951 config PCI_GODIRECT
1952 bool "Direct"
1953
1954 config PCI_GOOLPC
1955 bool "OLPC XO-1"
1956 depends on OLPC
1957
1958 config PCI_GOANY
1959 bool "Any"
1960
1961 endchoice
1962
1963 config PCI_BIOS
1964 def_bool y
1965 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1966
1967 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1968 config PCI_DIRECT
1969 def_bool y
1970 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
1971
1972 config PCI_MMCONFIG
1973 def_bool y
1974 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
1975
1976 config PCI_OLPC
1977 def_bool y
1978 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1979
1980 config PCI_XEN
1981 def_bool y
1982 depends on PCI && XEN
1983 select SWIOTLB_XEN
1984
1985 config PCI_DOMAINS
1986 def_bool y
1987 depends on PCI
1988
1989 config PCI_MMCONFIG
1990 bool "Support mmconfig PCI config space access"
1991 depends on X86_64 && PCI && ACPI
1992
1993 config PCI_CNB20LE_QUIRK
1994 bool "Read CNB20LE Host Bridge Windows" if EXPERT
1995 depends on PCI && EXPERIMENTAL
1996 help
1997 Read the PCI windows out of the CNB20LE host bridge. This allows
1998 PCI hotplug to work on systems with the CNB20LE chipset which do
1999 not have ACPI.
2000
2001 There's no public spec for this chipset, and this functionality
2002 is known to be incomplete.
2003
2004 You should say N unless you know you need this.
2005
2006 source "drivers/pci/pcie/Kconfig"
2007
2008 source "drivers/pci/Kconfig"
2009
2010 # x86_64 have no ISA slots, but can have ISA-style DMA.
2011 config ISA_DMA_API
2012 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2013 default y
2014 help
2015 Enables ISA-style DMA support for devices requiring such controllers.
2016 If unsure, say Y.
2017
2018 if X86_32
2019
2020 config ISA
2021 bool "ISA support"
2022 ---help---
2023 Find out whether you have ISA slots on your motherboard. ISA is the
2024 name of a bus system, i.e. the way the CPU talks to the other stuff
2025 inside your box. Other bus systems are PCI, EISA, MicroChannel
2026 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2027 newer boards don't support it. If you have ISA, say Y, otherwise N.
2028
2029 config EISA
2030 bool "EISA support"
2031 depends on ISA
2032 ---help---
2033 The Extended Industry Standard Architecture (EISA) bus was
2034 developed as an open alternative to the IBM MicroChannel bus.
2035
2036 The EISA bus provided some of the features of the IBM MicroChannel
2037 bus while maintaining backward compatibility with cards made for
2038 the older ISA bus. The EISA bus saw limited use between 1988 and
2039 1995 when it was made obsolete by the PCI bus.
2040
2041 Say Y here if you are building a kernel for an EISA-based machine.
2042
2043 Otherwise, say N.
2044
2045 source "drivers/eisa/Kconfig"
2046
2047 config SCx200
2048 tristate "NatSemi SCx200 support"
2049 ---help---
2050 This provides basic support for National Semiconductor's
2051 (now AMD's) Geode processors. The driver probes for the
2052 PCI-IDs of several on-chip devices, so its a good dependency
2053 for other scx200_* drivers.
2054
2055 If compiled as a module, the driver is named scx200.
2056
2057 config SCx200HR_TIMER
2058 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2059 depends on SCx200
2060 default y
2061 ---help---
2062 This driver provides a clocksource built upon the on-chip
2063 27MHz high-resolution timer. Its also a workaround for
2064 NSC Geode SC-1100's buggy TSC, which loses time when the
2065 processor goes idle (as is done by the scheduler). The
2066 other workaround is idle=poll boot option.
2067
2068 config OLPC
2069 bool "One Laptop Per Child support"
2070 depends on !X86_PAE
2071 select GPIOLIB
2072 select OF
2073 select OF_PROMTREE
2074 select IRQ_DOMAIN
2075 ---help---
2076 Add support for detecting the unique features of the OLPC
2077 XO hardware.
2078
2079 config OLPC_XO1_PM
2080 bool "OLPC XO-1 Power Management"
2081 depends on OLPC && MFD_CS5535 && PM_SLEEP
2082 select MFD_CORE
2083 ---help---
2084 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2085
2086 config OLPC_XO1_RTC
2087 bool "OLPC XO-1 Real Time Clock"
2088 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2089 ---help---
2090 Add support for the XO-1 real time clock, which can be used as a
2091 programmable wakeup source.
2092
2093 config OLPC_XO1_SCI
2094 bool "OLPC XO-1 SCI extras"
2095 depends on OLPC && OLPC_XO1_PM
2096 select POWER_SUPPLY
2097 select GPIO_CS5535
2098 select MFD_CORE
2099 ---help---
2100 Add support for SCI-based features of the OLPC XO-1 laptop:
2101 - EC-driven system wakeups
2102 - Power button
2103 - Ebook switch
2104 - Lid switch
2105 - AC adapter status updates
2106 - Battery status updates
2107
2108 config OLPC_XO15_SCI
2109 bool "OLPC XO-1.5 SCI extras"
2110 depends on OLPC && ACPI
2111 select POWER_SUPPLY
2112 ---help---
2113 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2114 - EC-driven system wakeups
2115 - AC adapter status updates
2116 - Battery status updates
2117
2118 config ALIX
2119 bool "PCEngines ALIX System Support (LED setup)"
2120 select GPIOLIB
2121 ---help---
2122 This option enables system support for the PCEngines ALIX.
2123 At present this just sets up LEDs for GPIO control on
2124 ALIX2/3/6 boards. However, other system specific setup should
2125 get added here.
2126
2127 Note: You must still enable the drivers for GPIO and LED support
2128 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2129
2130 Note: You have to set alix.force=1 for boards with Award BIOS.
2131
2132 config NET5501
2133 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2134 select GPIOLIB
2135 ---help---
2136 This option enables system support for the Soekris Engineering net5501.
2137
2138 config GEOS
2139 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2140 select GPIOLIB
2141 depends on DMI
2142 ---help---
2143 This option enables system support for the Traverse Technologies GEOS.
2144
2145 endif # X86_32
2146
2147 config AMD_NB
2148 def_bool y
2149 depends on CPU_SUP_AMD && PCI
2150
2151 source "drivers/pcmcia/Kconfig"
2152
2153 source "drivers/pci/hotplug/Kconfig"
2154
2155 config RAPIDIO
2156 bool "RapidIO support"
2157 depends on PCI
2158 default n
2159 help
2160 If you say Y here, the kernel will include drivers and
2161 infrastructure code to support RapidIO interconnect devices.
2162
2163 source "drivers/rapidio/Kconfig"
2164
2165 endmenu
2166
2167
2168 menu "Executable file formats / Emulations"
2169
2170 source "fs/Kconfig.binfmt"
2171
2172 config IA32_EMULATION
2173 bool "IA32 Emulation"
2174 depends on X86_64
2175 select COMPAT_BINFMT_ELF
2176 select HAVE_UID16
2177 ---help---
2178 Include code to run legacy 32-bit programs under a
2179 64-bit kernel. You should likely turn this on, unless you're
2180 100% sure that you don't have any 32-bit programs left.
2181
2182 config IA32_AOUT
2183 tristate "IA32 a.out support"
2184 depends on IA32_EMULATION
2185 ---help---
2186 Support old a.out binaries in the 32bit emulation.
2187
2188 config X86_X32
2189 bool "x32 ABI for 64-bit mode (EXPERIMENTAL)"
2190 depends on X86_64 && IA32_EMULATION && EXPERIMENTAL
2191 ---help---
2192 Include code to run binaries for the x32 native 32-bit ABI
2193 for 64-bit processors. An x32 process gets access to the
2194 full 64-bit register file and wide data path while leaving
2195 pointers at 32 bits for smaller memory footprint.
2196
2197 You will need a recent binutils (2.22 or later) with
2198 elf32_x86_64 support enabled to compile a kernel with this
2199 option set.
2200
2201 config COMPAT
2202 def_bool y
2203 depends on IA32_EMULATION || X86_X32
2204 select ARCH_WANT_OLD_COMPAT_IPC
2205
2206 if COMPAT
2207 config COMPAT_FOR_U64_ALIGNMENT
2208 def_bool y
2209
2210 config SYSVIPC_COMPAT
2211 def_bool y
2212 depends on SYSVIPC
2213
2214 config KEYS_COMPAT
2215 def_bool y
2216 depends on KEYS
2217 endif
2218
2219 endmenu
2220
2221
2222 config HAVE_ATOMIC_IOMAP
2223 def_bool y
2224 depends on X86_32
2225
2226 config HAVE_TEXT_POKE_SMP
2227 bool
2228 select STOP_MACHINE if SMP
2229
2230 config X86_DEV_DMA_OPS
2231 bool
2232 depends on X86_64 || STA2X11
2233
2234 config X86_DMA_REMAP
2235 bool
2236 depends on STA2X11
2237
2238 source "net/Kconfig"
2239
2240 source "drivers/Kconfig"
2241
2242 source "drivers/firmware/Kconfig"
2243
2244 source "fs/Kconfig"
2245
2246 source "arch/x86/Kconfig.debug"
2247
2248 source "security/Kconfig"
2249
2250 source "crypto/Kconfig"
2251
2252 source "arch/x86/kvm/Kconfig"
2253
2254 source "lib/Kconfig"