| blob | 880fcb6c86f484c602afa6bbcfb436d48647f8c9 |
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
9 config X86_32
10 def_bool !64BIT
11 select CLKSRC_I8253
13 config X86_64
14 def_bool 64BIT
16 ### Arch settings
17 config X86
18 def_bool y
19 select HAVE_AOUT if X86_32
20 select HAVE_READQ
21 select HAVE_WRITEQ
22 select HAVE_UNSTABLE_SCHED_CLOCK
23 select HAVE_IDE
24 select HAVE_OPROFILE
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 ARCH_WANT_OPTIONAL_GPIOLIB
31 select ARCH_WANT_FRAME_POINTERS
32 select HAVE_DMA_ATTRS
33 select HAVE_KRETPROBES
34 select HAVE_OPTPROBES
35 select HAVE_FTRACE_MCOUNT_RECORD
36 select HAVE_C_RECORDMCOUNT
37 select HAVE_DYNAMIC_FTRACE
38 select HAVE_FUNCTION_TRACER
39 select HAVE_FUNCTION_GRAPH_TRACER
40 select HAVE_FUNCTION_GRAPH_FP_TEST
41 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
42 select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
43 select HAVE_SYSCALL_TRACEPOINTS
44 select HAVE_KVM
45 select HAVE_ARCH_KGDB
46 select HAVE_ARCH_TRACEHOOK
47 select HAVE_GENERIC_DMA_COHERENT if X86_32
48 select HAVE_EFFICIENT_UNALIGNED_ACCESS
49 select USER_STACKTRACE_SUPPORT
50 select HAVE_REGS_AND_STACK_ACCESS_API
51 select HAVE_DMA_API_DEBUG
52 select HAVE_KERNEL_GZIP
53 select HAVE_KERNEL_BZIP2
54 select HAVE_KERNEL_LZMA
55 select HAVE_KERNEL_XZ
56 select HAVE_KERNEL_LZO
57 select HAVE_HW_BREAKPOINT
58 select HAVE_MIXED_BREAKPOINTS_REGS
59 select PERF_EVENTS
60 select HAVE_PERF_EVENTS_NMI
61 select ANON_INODES
62 select HAVE_ARCH_KMEMCHECK
63 select HAVE_USER_RETURN_NOTIFIER
64 select HAVE_ARCH_JUMP_LABEL
65 select HAVE_TEXT_POKE_SMP
66 select HAVE_GENERIC_HARDIRQS
67 select HAVE_SPARSE_IRQ
68 select GENERIC_FIND_FIRST_BIT
69 select GENERIC_FIND_NEXT_BIT
70 select GENERIC_IRQ_PROBE
71 select GENERIC_PENDING_IRQ if SMP
72 select GENERIC_IRQ_SHOW
73 select IRQ_FORCED_THREADING
74 select USE_GENERIC_SMP_HELPERS if SMP
75 select HAVE_BPF_JIT if (X86_64 && NET)
77 config INSTRUCTION_DECODER
78 def_bool (KPROBES || PERF_EVENTS)
80 config OUTPUT_FORMAT
81 string
82 default "elf32-i386" if X86_32
83 default "elf64-x86-64" if X86_64
85 config ARCH_DEFCONFIG
86 string
87 default "arch/x86/configs/i386_defconfig" if X86_32
88 default "arch/x86/configs/x86_64_defconfig" if X86_64
90 config GENERIC_CMOS_UPDATE
91 def_bool y
93 config CLOCKSOURCE_WATCHDOG
94 def_bool y
96 config GENERIC_CLOCKEVENTS
97 def_bool y
99 config GENERIC_CLOCKEVENTS_BROADCAST
100 def_bool y
101 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
103 config LOCKDEP_SUPPORT
104 def_bool y
106 config STACKTRACE_SUPPORT
107 def_bool y
109 config HAVE_LATENCYTOP_SUPPORT
110 def_bool y
112 config MMU
113 def_bool y
115 config ZONE_DMA
116 bool "DMA memory allocation support" if EXPERT
117 default y
118 help
119 DMA memory allocation support allows devices with less than 32-bit
120 addressing to allocate within the first 16MB of address space.
121 Disable if no such devices will be used.
123 If unsure, say Y.
125 config SBUS
126 bool
128 config NEED_DMA_MAP_STATE
129 def_bool (X86_64 || DMAR || DMA_API_DEBUG)
131 config NEED_SG_DMA_LENGTH
132 def_bool y
134 config GENERIC_ISA_DMA
135 def_bool ISA_DMA_API
137 config GENERIC_IOMAP
138 def_bool y
140 config GENERIC_BUG
141 def_bool y
142 depends on BUG
143 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
145 config GENERIC_BUG_RELATIVE_POINTERS
146 bool
148 config GENERIC_HWEIGHT
149 def_bool y
151 config GENERIC_GPIO
152 bool
154 config ARCH_MAY_HAVE_PC_FDC
155 def_bool ISA_DMA_API
157 config RWSEM_GENERIC_SPINLOCK
158 def_bool !X86_XADD
160 config RWSEM_XCHGADD_ALGORITHM
161 def_bool X86_XADD
163 config ARCH_HAS_CPU_IDLE_WAIT
164 def_bool y
166 config GENERIC_CALIBRATE_DELAY
167 def_bool y
169 config GENERIC_TIME_VSYSCALL
170 bool
171 default X86_64
173 config ARCH_HAS_CPU_RELAX
174 def_bool y
176 config ARCH_HAS_DEFAULT_IDLE
177 def_bool y
179 config ARCH_HAS_CACHE_LINE_SIZE
180 def_bool y
182 config HAVE_SETUP_PER_CPU_AREA
183 def_bool y
185 config NEED_PER_CPU_EMBED_FIRST_CHUNK
186 def_bool y
188 config NEED_PER_CPU_PAGE_FIRST_CHUNK
189 def_bool y
191 config HAVE_CPUMASK_OF_CPU_MAP
192 def_bool X86_64_SMP
194 config ARCH_HIBERNATION_POSSIBLE
195 def_bool y
197 config ARCH_SUSPEND_POSSIBLE
198 def_bool y
200 config ZONE_DMA32
201 bool
202 default X86_64
204 config ARCH_POPULATES_NODE_MAP
205 def_bool y
207 config AUDIT_ARCH
208 bool
209 default X86_64
211 config ARCH_SUPPORTS_OPTIMIZED_INLINING
212 def_bool y
214 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
215 def_bool y
217 config HAVE_INTEL_TXT
218 def_bool y
219 depends on EXPERIMENTAL && DMAR && ACPI
221 config X86_32_SMP
222 def_bool y
223 depends on X86_32 && SMP
225 config X86_64_SMP
226 def_bool y
227 depends on X86_64 && SMP
229 config X86_HT
230 def_bool y
231 depends on SMP
233 config X86_32_LAZY_GS
234 def_bool y
235 depends on X86_32 && !CC_STACKPROTECTOR
237 config ARCH_HWEIGHT_CFLAGS
238 string
239 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
240 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
242 config KTIME_SCALAR
243 def_bool X86_32
245 config ARCH_CPU_PROBE_RELEASE
246 def_bool y
247 depends on HOTPLUG_CPU
249 source "init/Kconfig"
250 source "kernel/Kconfig.freezer"
252 menu "Processor type and features"
254 source "kernel/time/Kconfig"
256 config SMP
257 bool "Symmetric multi-processing support"
258 ---help---
259 This enables support for systems with more than one CPU. If you have
260 a system with only one CPU, like most personal computers, say N. If
261 you have a system with more than one CPU, say Y.
263 If you say N here, the kernel will run on single and multiprocessor
264 machines, but will use only one CPU of a multiprocessor machine. If
265 you say Y here, the kernel will run on many, but not all,
266 singleprocessor machines. On a singleprocessor machine, the kernel
267 will run faster if you say N here.
269 Note that if you say Y here and choose architecture "586" or
270 "Pentium" under "Processor family", the kernel will not work on 486
271 architectures. Similarly, multiprocessor kernels for the "PPro"
272 architecture may not work on all Pentium based boards.
274 People using multiprocessor machines who say Y here should also say
275 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
276 Management" code will be disabled if you say Y here.
278 See also <file:Documentation/i386/IO-APIC.txt>,
279 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
280 <http://www.tldp.org/docs.html#howto>.
282 If you don't know what to do here, say N.
284 config X86_X2APIC
285 bool "Support x2apic"
286 depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
287 ---help---
288 This enables x2apic support on CPUs that have this feature.
290 This allows 32-bit apic IDs (so it can support very large systems),
291 and accesses the local apic via MSRs not via mmio.
293 If you don't know what to do here, say N.
295 config X86_MPPARSE
296 bool "Enable MPS table" if ACPI
297 default y
298 depends on X86_LOCAL_APIC
299 ---help---
300 For old smp systems that do not have proper acpi support. Newer systems
301 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
303 config X86_BIGSMP
304 bool "Support for big SMP systems with more than 8 CPUs"
305 depends on X86_32 && SMP
306 ---help---
307 This option is needed for the systems that have more than 8 CPUs
309 if X86_32
310 config X86_EXTENDED_PLATFORM
311 bool "Support for extended (non-PC) x86 platforms"
312 default y
313 ---help---
314 If you disable this option then the kernel will only support
315 standard PC platforms. (which covers the vast majority of
316 systems out there.)
318 If you enable this option then you'll be able to select support
319 for the following (non-PC) 32 bit x86 platforms:
320 AMD Elan
321 NUMAQ (IBM/Sequent)
322 RDC R-321x SoC
323 SGI 320/540 (Visual Workstation)
324 Summit/EXA (IBM x440)
325 Unisys ES7000 IA32 series
326 Moorestown MID devices
328 If you have one of these systems, or if you want to build a
329 generic distribution kernel, say Y here - otherwise say N.
330 endif
332 if X86_64
333 config X86_EXTENDED_PLATFORM
334 bool "Support for extended (non-PC) x86 platforms"
335 default y
336 ---help---
337 If you disable this option then the kernel will only support
338 standard PC platforms. (which covers the vast majority of
339 systems out there.)
341 If you enable this option then you'll be able to select support
342 for the following (non-PC) 64 bit x86 platforms:
343 ScaleMP vSMP
344 SGI Ultraviolet
346 If you have one of these systems, or if you want to build a
347 generic distribution kernel, say Y here - otherwise say N.
348 endif
349 # This is an alphabetically sorted list of 64 bit extended platforms
350 # Please maintain the alphabetic order if and when there are additions
352 config X86_VSMP
353 bool "ScaleMP vSMP"
354 select PARAVIRT_GUEST
355 select PARAVIRT
356 depends on X86_64 && PCI
357 depends on X86_EXTENDED_PLATFORM
358 ---help---
359 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
360 supposed to run on these EM64T-based machines. Only choose this option
361 if you have one of these machines.
363 config X86_UV
364 bool "SGI Ultraviolet"
365 depends on X86_64
366 depends on X86_EXTENDED_PLATFORM
367 depends on NUMA
368 depends on X86_X2APIC
369 ---help---
370 This option is needed in order to support SGI Ultraviolet systems.
371 If you don't have one of these, you should say N here.
373 # Following is an alphabetically sorted list of 32 bit extended platforms
374 # Please maintain the alphabetic order if and when there are additions
376 config X86_INTEL_CE
377 bool "CE4100 TV platform"
378 depends on PCI
379 depends on PCI_GODIRECT
380 depends on X86_32
381 depends on X86_EXTENDED_PLATFORM
382 select X86_REBOOTFIXUPS
383 select OF
384 select OF_EARLY_FLATTREE
385 ---help---
386 Select for the Intel CE media processor (CE4100) SOC.
387 This option compiles in support for the CE4100 SOC for settop
388 boxes and media devices.
390 config X86_MRST
391 bool "Moorestown MID platform"
392 depends on PCI
393 depends on PCI_GOANY
394 depends on X86_32
395 depends on X86_EXTENDED_PLATFORM
396 depends on X86_IO_APIC
397 select APB_TIMER
398 select I2C
399 select SPI
400 select INTEL_SCU_IPC
401 select X86_PLATFORM_DEVICES
402 ---help---
403 Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
404 Internet Device(MID) platform. Moorestown consists of two chips:
405 Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
406 Unlike standard x86 PCs, Moorestown does not have many legacy devices
407 nor standard legacy replacement devices/features. e.g. Moorestown does
408 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
410 config X86_RDC321X
411 bool "RDC R-321x SoC"
412 depends on X86_32
413 depends on X86_EXTENDED_PLATFORM
414 select M486
415 select X86_REBOOTFIXUPS
416 ---help---
417 This option is needed for RDC R-321x system-on-chip, also known
418 as R-8610-(G).
419 If you don't have one of these chips, you should say N here.
421 config X86_32_NON_STANDARD
422 bool "Support non-standard 32-bit SMP architectures"
423 depends on X86_32 && SMP
424 depends on X86_EXTENDED_PLATFORM
425 ---help---
426 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
427 subarchitectures. It is intended for a generic binary kernel.
428 if you select them all, kernel will probe it one by one. and will
429 fallback to default.
431 # Alphabetically sorted list of Non standard 32 bit platforms
433 config X86_NUMAQ
434 bool "NUMAQ (IBM/Sequent)"
435 depends on X86_32_NON_STANDARD
436 depends on PCI
437 select NUMA
438 select X86_MPPARSE
439 ---help---
440 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
441 NUMA multiquad box. This changes the way that processors are
442 bootstrapped, and uses Clustered Logical APIC addressing mode instead
443 of Flat Logical. You will need a new lynxer.elf file to flash your
444 firmware with - send email to <Martin.Bligh@us.ibm.com>.
446 config X86_SUPPORTS_MEMORY_FAILURE
447 def_bool y
448 # MCE code calls memory_failure():
449 depends on X86_MCE
450 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
451 depends on !X86_NUMAQ
452 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
453 depends on X86_64 || !SPARSEMEM
454 select ARCH_SUPPORTS_MEMORY_FAILURE
456 config X86_VISWS
457 bool "SGI 320/540 (Visual Workstation)"
458 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
459 depends on X86_32_NON_STANDARD
460 ---help---
461 The SGI Visual Workstation series is an IA32-based workstation
462 based on SGI systems chips with some legacy PC hardware attached.
464 Say Y here to create a kernel to run on the SGI 320 or 540.
466 A kernel compiled for the Visual Workstation will run on general
467 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
469 config X86_SUMMIT
470 bool "Summit/EXA (IBM x440)"
471 depends on X86_32_NON_STANDARD
472 ---help---
473 This option is needed for IBM systems that use the Summit/EXA chipset.
474 In particular, it is needed for the x440.
476 config X86_ES7000
477 bool "Unisys ES7000 IA32 series"
478 depends on X86_32_NON_STANDARD && X86_BIGSMP
479 ---help---
480 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
481 supposed to run on an IA32-based Unisys ES7000 system.
483 config X86_32_IRIS
484 tristate "Eurobraille/Iris poweroff module"
485 depends on X86_32
486 ---help---
487 The Iris machines from EuroBraille do not have APM or ACPI support
488 to shut themselves down properly. A special I/O sequence is
489 needed to do so, which is what this module does at
490 kernel shutdown.
492 This is only for Iris machines from EuroBraille.
494 If unused, say N.
496 config SCHED_OMIT_FRAME_POINTER
497 def_bool y
498 prompt "Single-depth WCHAN output"
499 depends on X86
500 ---help---
501 Calculate simpler /proc/<PID>/wchan values. If this option
502 is disabled then wchan values will recurse back to the
503 caller function. This provides more accurate wchan values,
504 at the expense of slightly more scheduling overhead.
506 If in doubt, say "Y".
508 menuconfig PARAVIRT_GUEST
509 bool "Paravirtualized guest support"
510 ---help---
511 Say Y here to get to see options related to running Linux under
512 various hypervisors. This option alone does not add any kernel code.
514 If you say N, all options in this submenu will be skipped and disabled.
516 if PARAVIRT_GUEST
518 source "arch/x86/xen/Kconfig"
520 config KVM_CLOCK
521 bool "KVM paravirtualized clock"
522 select PARAVIRT
523 select PARAVIRT_CLOCK
524 ---help---
525 Turning on this option will allow you to run a paravirtualized clock
526 when running over the KVM hypervisor. Instead of relying on a PIT
527 (or probably other) emulation by the underlying device model, the host
528 provides the guest with timing infrastructure such as time of day, and
529 system time
531 config KVM_GUEST
532 bool "KVM Guest support"
533 select PARAVIRT
534 ---help---
535 This option enables various optimizations for running under the KVM
536 hypervisor.
538 source "arch/x86/lguest/Kconfig"
540 config PARAVIRT
541 bool "Enable paravirtualization code"
542 ---help---
543 This changes the kernel so it can modify itself when it is run
544 under a hypervisor, potentially improving performance significantly
545 over full virtualization. However, when run without a hypervisor
546 the kernel is theoretically slower and slightly larger.
548 config PARAVIRT_SPINLOCKS
549 bool "Paravirtualization layer for spinlocks"
550 depends on PARAVIRT && SMP && EXPERIMENTAL
551 ---help---
552 Paravirtualized spinlocks allow a pvops backend to replace the
553 spinlock implementation with something virtualization-friendly
554 (for example, block the virtual CPU rather than spinning).
556 Unfortunately the downside is an up to 5% performance hit on
557 native kernels, with various workloads.
559 If you are unsure how to answer this question, answer N.
561 config PARAVIRT_CLOCK
562 bool
564 endif
566 config PARAVIRT_DEBUG
567 bool "paravirt-ops debugging"
568 depends on PARAVIRT && DEBUG_KERNEL
569 ---help---
570 Enable to debug paravirt_ops internals. Specifically, BUG if
571 a paravirt_op is missing when it is called.
573 config NO_BOOTMEM
574 def_bool y
576 config MEMTEST
577 bool "Memtest"
578 ---help---
579 This option adds a kernel parameter 'memtest', which allows memtest
580 to be set.
581 memtest=0, mean disabled; -- default
582 memtest=1, mean do 1 test pattern;
583 ...
584 memtest=4, mean do 4 test patterns.
585 If you are unsure how to answer this question, answer N.
587 config X86_SUMMIT_NUMA
588 def_bool y
589 depends on X86_32 && NUMA && X86_32_NON_STANDARD
591 config X86_CYCLONE_TIMER
592 def_bool y
593 depends on X86_32_NON_STANDARD
595 source "arch/x86/Kconfig.cpu"
597 config HPET_TIMER
598 def_bool X86_64
599 prompt "HPET Timer Support" if X86_32
600 ---help---
601 Use the IA-PC HPET (High Precision Event Timer) to manage
602 time in preference to the PIT and RTC, if a HPET is
603 present.
604 HPET is the next generation timer replacing legacy 8254s.
605 The HPET provides a stable time base on SMP
606 systems, unlike the TSC, but it is more expensive to access,
607 as it is off-chip. You can find the HPET spec at
608 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
610 You can safely choose Y here. However, HPET will only be
611 activated if the platform and the BIOS support this feature.
612 Otherwise the 8254 will be used for timing services.
614 Choose N to continue using the legacy 8254 timer.
616 config HPET_EMULATE_RTC
617 def_bool y
618 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
620 config APB_TIMER
621 def_bool y if MRST
622 prompt "Langwell APB Timer Support" if X86_MRST
623 help
624 APB timer is the replacement for 8254, HPET on X86 MID platforms.
625 The APBT provides a stable time base on SMP
626 systems, unlike the TSC, but it is more expensive to access,
627 as it is off-chip. APB timers are always running regardless of CPU
628 C states, they are used as per CPU clockevent device when possible.
630 # Mark as expert because too many people got it wrong.
631 # The code disables itself when not needed.
632 config DMI
633 default y
634 bool "Enable DMI scanning" if EXPERT
635 ---help---
636 Enabled scanning of DMI to identify machine quirks. Say Y
637 here unless you have verified that your setup is not
638 affected by entries in the DMI blacklist. Required by PNP
639 BIOS code.
641 config GART_IOMMU
642 bool "GART IOMMU support" if EXPERT
643 default y
644 select SWIOTLB
645 depends on X86_64 && PCI && AMD_NB
646 ---help---
647 Support for full DMA access of devices with 32bit memory access only
648 on systems with more than 3GB. This is usually needed for USB,
649 sound, many IDE/SATA chipsets and some other devices.
650 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
651 based hardware IOMMU and a software bounce buffer based IOMMU used
652 on Intel systems and as fallback.
653 The code is only active when needed (enough memory and limited
654 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
655 too.
657 config CALGARY_IOMMU
658 bool "IBM Calgary IOMMU support"
659 select SWIOTLB
660 depends on X86_64 && PCI && EXPERIMENTAL
661 ---help---
662 Support for hardware IOMMUs in IBM's xSeries x366 and x460
663 systems. Needed to run systems with more than 3GB of memory
664 properly with 32-bit PCI devices that do not support DAC
665 (Double Address Cycle). Calgary also supports bus level
666 isolation, where all DMAs pass through the IOMMU. This
667 prevents them from going anywhere except their intended
668 destination. This catches hard-to-find kernel bugs and
669 mis-behaving drivers and devices that do not use the DMA-API
670 properly to set up their DMA buffers. The IOMMU can be
671 turned off at boot time with the iommu=off parameter.
672 Normally the kernel will make the right choice by itself.
673 If unsure, say Y.
675 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
676 def_bool y
677 prompt "Should Calgary be enabled by default?"
678 depends on CALGARY_IOMMU
679 ---help---
680 Should Calgary be enabled by default? if you choose 'y', Calgary
681 will be used (if it exists). If you choose 'n', Calgary will not be
682 used even if it exists. If you choose 'n' and would like to use
683 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
684 If unsure, say Y.
686 config AMD_IOMMU
687 bool "AMD IOMMU support"
688 select SWIOTLB
689 select PCI_MSI
690 select PCI_IOV
691 depends on X86_64 && PCI && ACPI
692 ---help---
693 With this option you can enable support for AMD IOMMU hardware in
694 your system. An IOMMU is a hardware component which provides
695 remapping of DMA memory accesses from devices. With an AMD IOMMU you
696 can isolate the the DMA memory of different devices and protect the
697 system from misbehaving device drivers or hardware.
699 You can find out if your system has an AMD IOMMU if you look into
700 your BIOS for an option to enable it or if you have an IVRS ACPI
701 table.
703 config AMD_IOMMU_STATS
704 bool "Export AMD IOMMU statistics to debugfs"
705 depends on AMD_IOMMU
706 select DEBUG_FS
707 ---help---
708 This option enables code in the AMD IOMMU driver to collect various
709 statistics about whats happening in the driver and exports that
710 information to userspace via debugfs.
711 If unsure, say N.
713 # need this always selected by IOMMU for the VIA workaround
714 config SWIOTLB
715 def_bool y if X86_64
716 ---help---
717 Support for software bounce buffers used on x86-64 systems
718 which don't have a hardware IOMMU (e.g. the current generation
719 of Intel's x86-64 CPUs). Using this PCI devices which can only
720 access 32-bits of memory can be used on systems with more than
721 3 GB of memory. If unsure, say Y.
723 config IOMMU_HELPER
724 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
726 config IOMMU_API
727 def_bool (AMD_IOMMU || DMAR)
729 config MAXSMP
730 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
731 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
732 select CPUMASK_OFFSTACK
733 ---help---
734 Enable maximum number of CPUS and NUMA Nodes for this architecture.
735 If unsure, say N.
737 config NR_CPUS
738 int "Maximum number of CPUs" if SMP && !MAXSMP
739 range 2 8 if SMP && X86_32 && !X86_BIGSMP
740 range 2 512 if SMP && !MAXSMP
741 default "1" if !SMP
742 default "4096" if MAXSMP
743 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
744 default "8" if SMP
745 ---help---
746 This allows you to specify the maximum number of CPUs which this
747 kernel will support. The maximum supported value is 512 and the
748 minimum value which makes sense is 2.
750 This is purely to save memory - each supported CPU adds
751 approximately eight kilobytes to the kernel image.
753 config SCHED_SMT
754 bool "SMT (Hyperthreading) scheduler support"
755 depends on X86_HT
756 ---help---
757 SMT scheduler support improves the CPU scheduler's decision making
758 when dealing with Intel Pentium 4 chips with HyperThreading at a
759 cost of slightly increased overhead in some places. If unsure say
760 N here.
762 config SCHED_MC
763 def_bool y
764 prompt "Multi-core scheduler support"
765 depends on X86_HT
766 ---help---
767 Multi-core scheduler support improves the CPU scheduler's decision
768 making when dealing with multi-core CPU chips at a cost of slightly
769 increased overhead in some places. If unsure say N here.
771 config IRQ_TIME_ACCOUNTING
772 bool "Fine granularity task level IRQ time accounting"
773 default n
774 ---help---
775 Select this option to enable fine granularity task irq time
776 accounting. This is done by reading a timestamp on each
777 transitions between softirq and hardirq state, so there can be a
778 small performance impact.
780 If in doubt, say N here.
782 source "kernel/Kconfig.preempt"
784 config X86_UP_APIC
785 bool "Local APIC support on uniprocessors"
786 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
787 ---help---
788 A local APIC (Advanced Programmable Interrupt Controller) is an
789 integrated interrupt controller in the CPU. If you have a single-CPU
790 system which has a processor with a local APIC, you can say Y here to
791 enable and use it. If you say Y here even though your machine doesn't
792 have a local APIC, then the kernel will still run with no slowdown at
793 all. The local APIC supports CPU-generated self-interrupts (timer,
794 performance counters), and the NMI watchdog which detects hard
795 lockups.
797 config X86_UP_IOAPIC
798 bool "IO-APIC support on uniprocessors"
799 depends on X86_UP_APIC
800 ---help---
801 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
802 SMP-capable replacement for PC-style interrupt controllers. Most
803 SMP systems and many recent uniprocessor systems have one.
805 If you have a single-CPU system with an IO-APIC, you can say Y here
806 to use it. If you say Y here even though your machine doesn't have
807 an IO-APIC, then the kernel will still run with no slowdown at all.
809 config X86_LOCAL_APIC
810 def_bool y
811 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
813 config X86_IO_APIC
814 def_bool y
815 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC
817 config X86_VISWS_APIC
818 def_bool y
819 depends on X86_32 && X86_VISWS
821 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
822 bool "Reroute for broken boot IRQs"
823 depends on X86_IO_APIC
824 ---help---
825 This option enables a workaround that fixes a source of
826 spurious interrupts. This is recommended when threaded
827 interrupt handling is used on systems where the generation of
828 superfluous "boot interrupts" cannot be disabled.
830 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
831 entry in the chipset's IO-APIC is masked (as, e.g. the RT
832 kernel does during interrupt handling). On chipsets where this
833 boot IRQ generation cannot be disabled, this workaround keeps
834 the original IRQ line masked so that only the equivalent "boot
835 IRQ" is delivered to the CPUs. The workaround also tells the
836 kernel to set up the IRQ handler on the boot IRQ line. In this
837 way only one interrupt is delivered to the kernel. Otherwise
838 the spurious second interrupt may cause the kernel to bring
839 down (vital) interrupt lines.
841 Only affects "broken" chipsets. Interrupt sharing may be
842 increased on these systems.
844 config X86_MCE
845 bool "Machine Check / overheating reporting"
846 ---help---
847 Machine Check support allows the processor to notify the
848 kernel if it detects a problem (e.g. overheating, data corruption).
849 The action the kernel takes depends on the severity of the problem,
850 ranging from warning messages to halting the machine.
852 config X86_MCE_INTEL
853 def_bool y
854 prompt "Intel MCE features"
855 depends on X86_MCE && X86_LOCAL_APIC
856 ---help---
857 Additional support for intel specific MCE features such as
858 the thermal monitor.
860 config X86_MCE_AMD
861 def_bool y
862 prompt "AMD MCE features"
863 depends on X86_MCE && X86_LOCAL_APIC
864 ---help---
865 Additional support for AMD specific MCE features such as
866 the DRAM Error Threshold.
868 config X86_ANCIENT_MCE
869 bool "Support for old Pentium 5 / WinChip machine checks"
870 depends on X86_32 && X86_MCE
871 ---help---
872 Include support for machine check handling on old Pentium 5 or WinChip
873 systems. These typically need to be enabled explicitely on the command
874 line.
876 config X86_MCE_THRESHOLD
877 depends on X86_MCE_AMD || X86_MCE_INTEL
878 def_bool y
880 config X86_MCE_INJECT
881 depends on X86_MCE
882 tristate "Machine check injector support"
883 ---help---
884 Provide support for injecting machine checks for testing purposes.
885 If you don't know what a machine check is and you don't do kernel
886 QA it is safe to say n.
888 config X86_THERMAL_VECTOR
889 def_bool y
890 depends on X86_MCE_INTEL
892 config VM86
893 bool "Enable VM86 support" if EXPERT
894 default y
895 depends on X86_32
896 ---help---
897 This option is required by programs like DOSEMU to run 16-bit legacy
898 code on X86 processors. It also may be needed by software like
899 XFree86 to initialize some video cards via BIOS. Disabling this
900 option saves about 6k.
902 config TOSHIBA
903 tristate "Toshiba Laptop support"
904 depends on X86_32
905 ---help---
906 This adds a driver to safely access the System Management Mode of
907 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
908 not work on models with a Phoenix BIOS. The System Management Mode
909 is used to set the BIOS and power saving options on Toshiba portables.
911 For information on utilities to make use of this driver see the
912 Toshiba Linux utilities web site at:
913 <http://www.buzzard.org.uk/toshiba/>.
915 Say Y if you intend to run this kernel on a Toshiba portable.
916 Say N otherwise.
918 config I8K
919 tristate "Dell laptop support"
920 ---help---
921 This adds a driver to safely access the System Management Mode
922 of the CPU on the Dell Inspiron 8000. The System Management Mode
923 is used to read cpu temperature and cooling fan status and to
924 control the fans on the I8K portables.
926 This driver has been tested only on the Inspiron 8000 but it may
927 also work with other Dell laptops. You can force loading on other
928 models by passing the parameter `force=1' to the module. Use at
929 your own risk.
931 For information on utilities to make use of this driver see the
932 I8K Linux utilities web site at:
933 <http://people.debian.org/~dz/i8k/>
935 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
936 Say N otherwise.
938 config X86_REBOOTFIXUPS
939 bool "Enable X86 board specific fixups for reboot"
940 depends on X86_32
941 ---help---
942 This enables chipset and/or board specific fixups to be done
943 in order to get reboot to work correctly. This is only needed on
944 some combinations of hardware and BIOS. The symptom, for which
945 this config is intended, is when reboot ends with a stalled/hung
946 system.
948 Currently, the only fixup is for the Geode machines using
949 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
951 Say Y if you want to enable the fixup. Currently, it's safe to
952 enable this option even if you don't need it.
953 Say N otherwise.
955 config MICROCODE
956 tristate "/dev/cpu/microcode - microcode support"
957 select FW_LOADER
958 ---help---
959 If you say Y here, you will be able to update the microcode on
960 certain Intel and AMD processors. The Intel support is for the
961 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
962 Pentium 4, Xeon etc. The AMD support is for family 0x10 and
963 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
964 You will obviously need the actual microcode binary data itself
965 which is not shipped with the Linux kernel.
967 This option selects the general module only, you need to select
968 at least one vendor specific module as well.
970 To compile this driver as a module, choose M here: the
971 module will be called microcode.
973 config MICROCODE_INTEL
974 bool "Intel microcode patch loading support"
975 depends on MICROCODE
976 default MICROCODE
977 select FW_LOADER
978 ---help---
979 This options enables microcode patch loading support for Intel
980 processors.
982 For latest news and information on obtaining all the required
983 Intel ingredients for this driver, check:
984 <http://www.urbanmyth.org/microcode/>.
986 config MICROCODE_AMD
987 bool "AMD microcode patch loading support"
988 depends on MICROCODE
989 select FW_LOADER
990 ---help---
991 If you select this option, microcode patch loading support for AMD
992 processors will be enabled.
994 config MICROCODE_OLD_INTERFACE
995 def_bool y
996 depends on MICROCODE
998 config X86_MSR
999 tristate "/dev/cpu/*/msr - Model-specific register support"
1000 ---help---
1001 This device gives privileged processes access to the x86
1002 Model-Specific Registers (MSRs). It is a character device with
1003 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1004 MSR accesses are directed to a specific CPU on multi-processor
1005 systems.
1007 config X86_CPUID
1008 tristate "/dev/cpu/*/cpuid - CPU information support"
1009 ---help---
1010 This device gives processes access to the x86 CPUID instruction to
1011 be executed on a specific processor. It is a character device
1012 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1013 /dev/cpu/31/cpuid.
1015 choice
1016 prompt "High Memory Support"
1017 default HIGHMEM64G if X86_NUMAQ
1018 default HIGHMEM4G
1019 depends on X86_32
1021 config NOHIGHMEM
1022 bool "off"
1023 depends on !X86_NUMAQ
1024 ---help---
1025 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1026 However, the address space of 32-bit x86 processors is only 4
1027 Gigabytes large. That means that, if you have a large amount of
1028 physical memory, not all of it can be "permanently mapped" by the
1029 kernel. The physical memory that's not permanently mapped is called
1030 "high memory".
1032 If you are compiling a kernel which will never run on a machine with
1033 more than 1 Gigabyte total physical RAM, answer "off" here (default
1034 choice and suitable for most users). This will result in a "3GB/1GB"
1035 split: 3GB are mapped so that each process sees a 3GB virtual memory
1036 space and the remaining part of the 4GB virtual memory space is used
1037 by the kernel to permanently map as much physical memory as
1038 possible.
1040 If the machine has between 1 and 4 Gigabytes physical RAM, then
1041 answer "4GB" here.
1043 If more than 4 Gigabytes is used then answer "64GB" here. This
1044 selection turns Intel PAE (Physical Address Extension) mode on.
1045 PAE implements 3-level paging on IA32 processors. PAE is fully
1046 supported by Linux, PAE mode is implemented on all recent Intel
1047 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1048 then the kernel will not boot on CPUs that don't support PAE!
1050 The actual amount of total physical memory will either be
1051 auto detected or can be forced by using a kernel command line option
1052 such as "mem=256M". (Try "man bootparam" or see the documentation of
1053 your boot loader (lilo or loadlin) about how to pass options to the
1054 kernel at boot time.)
1056 If unsure, say "off".
1058 config HIGHMEM4G
1059 bool "4GB"
1060 depends on !X86_NUMAQ
1061 ---help---
1062 Select this if you have a 32-bit processor and between 1 and 4
1063 gigabytes of physical RAM.
1065 config HIGHMEM64G
1066 bool "64GB"
1067 depends on !M386 && !M486
1068 select X86_PAE
1069 ---help---
1070 Select this if you have a 32-bit processor and more than 4
1071 gigabytes of physical RAM.
1073 endchoice
1075 choice
1076 depends on EXPERIMENTAL
1077 prompt "Memory split" if EXPERT
1078 default VMSPLIT_3G
1079 depends on X86_32
1080 ---help---
1081 Select the desired split between kernel and user memory.
1083 If the address range available to the kernel is less than the
1084 physical memory installed, the remaining memory will be available
1085 as "high memory". Accessing high memory is a little more costly
1086 than low memory, as it needs to be mapped into the kernel first.
1087 Note that increasing the kernel address space limits the range
1088 available to user programs, making the address space there
1089 tighter. Selecting anything other than the default 3G/1G split
1090 will also likely make your kernel incompatible with binary-only
1091 kernel modules.
1093 If you are not absolutely sure what you are doing, leave this
1094 option alone!
1096 config VMSPLIT_3G
1097 bool "3G/1G user/kernel split"
1098 config VMSPLIT_3G_OPT
1099 depends on !X86_PAE
1100 bool "3G/1G user/kernel split (for full 1G low memory)"
1101 config VMSPLIT_2G
1102 bool "2G/2G user/kernel split"
1103 config VMSPLIT_2G_OPT
1104 depends on !X86_PAE
1105 bool "2G/2G user/kernel split (for full 2G low memory)"
1106 config VMSPLIT_1G
1107 bool "1G/3G user/kernel split"
1108 endchoice
1110 config PAGE_OFFSET
1111 hex
1112 default 0xB0000000 if VMSPLIT_3G_OPT
1113 default 0x80000000 if VMSPLIT_2G
1114 default 0x78000000 if VMSPLIT_2G_OPT
1115 default 0x40000000 if VMSPLIT_1G
1116 default 0xC0000000
1117 depends on X86_32
1119 config HIGHMEM
1120 def_bool y
1121 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1123 config X86_PAE
1124 bool "PAE (Physical Address Extension) Support"
1125 depends on X86_32 && !HIGHMEM4G
1126 ---help---
1127 PAE is required for NX support, and furthermore enables
1128 larger swapspace support for non-overcommit purposes. It
1129 has the cost of more pagetable lookup overhead, and also
1130 consumes more pagetable space per process.
1132 config ARCH_PHYS_ADDR_T_64BIT
1133 def_bool X86_64 || X86_PAE
1135 config ARCH_DMA_ADDR_T_64BIT
1136 def_bool X86_64 || HIGHMEM64G
1138 config DIRECT_GBPAGES
1139 bool "Enable 1GB pages for kernel pagetables" if EXPERT
1140 default y
1141 depends on X86_64
1142 ---help---
1143 Allow the kernel linear mapping to use 1GB pages on CPUs that
1144 support it. This can improve the kernel's performance a tiny bit by
1145 reducing TLB pressure. If in doubt, say "Y".
1147 # Common NUMA Features
1148 config NUMA
1149 bool "Numa Memory Allocation and Scheduler Support"
1150 depends on SMP
1151 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1152 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1153 ---help---
1154 Enable NUMA (Non Uniform Memory Access) support.
1156 The kernel will try to allocate memory used by a CPU on the
1157 local memory controller of the CPU and add some more
1158 NUMA awareness to the kernel.
1160 For 64-bit this is recommended if the system is Intel Core i7
1161 (or later), AMD Opteron, or EM64T NUMA.
1163 For 32-bit this is only needed on (rare) 32-bit-only platforms
1164 that support NUMA topologies, such as NUMAQ / Summit, or if you
1165 boot a 32-bit kernel on a 64-bit NUMA platform.
1167 Otherwise, you should say N.
1169 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1170 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1172 config AMD_NUMA
1173 def_bool y
1174 prompt "Old style AMD Opteron NUMA detection"
1175 depends on NUMA && PCI
1176 ---help---
1177 Enable AMD NUMA node topology detection. You should say Y here if
1178 you have a multi processor AMD system. This uses an old method to
1179 read the NUMA configuration directly from the builtin Northbridge
1180 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1181 which also takes priority if both are compiled in.
1183 config X86_64_ACPI_NUMA
1184 def_bool y
1185 prompt "ACPI NUMA detection"
1186 depends on X86_64 && NUMA && ACPI && PCI
1187 select ACPI_NUMA
1188 ---help---
1189 Enable ACPI SRAT based node topology detection.
1191 # Some NUMA nodes have memory ranges that span
1192 # other nodes. Even though a pfn is valid and
1193 # between a node's start and end pfns, it may not
1194 # reside on that node. See memmap_init_zone()
1195 # for details.
1196 config NODES_SPAN_OTHER_NODES
1197 def_bool y
1198 depends on X86_64_ACPI_NUMA
1200 config NUMA_EMU
1201 bool "NUMA emulation"
1202 depends on NUMA
1203 ---help---
1204 Enable NUMA emulation. A flat machine will be split
1205 into virtual nodes when booted with "numa=fake=N", where N is the
1206 number of nodes. This is only useful for debugging.
1208 config NODES_SHIFT
1209 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1210 range 1 10
1211 default "10" if MAXSMP
1212 default "6" if X86_64
1213 default "4" if X86_NUMAQ
1214 default "3"
1215 depends on NEED_MULTIPLE_NODES
1216 ---help---
1217 Specify the maximum number of NUMA Nodes available on the target
1218 system. Increases memory reserved to accommodate various tables.
1220 config HAVE_ARCH_BOOTMEM
1221 def_bool y
1222 depends on X86_32 && NUMA
1224 config HAVE_ARCH_ALLOC_REMAP
1225 def_bool y
1226 depends on X86_32 && NUMA
1228 config ARCH_HAVE_MEMORY_PRESENT
1229 def_bool y
1230 depends on X86_32 && DISCONTIGMEM
1232 config NEED_NODE_MEMMAP_SIZE
1233 def_bool y
1234 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1236 config ARCH_FLATMEM_ENABLE
1237 def_bool y
1238 depends on X86_32 && !NUMA
1240 config ARCH_DISCONTIGMEM_ENABLE
1241 def_bool y
1242 depends on NUMA && X86_32
1244 config ARCH_DISCONTIGMEM_DEFAULT
1245 def_bool y
1246 depends on NUMA && X86_32
1248 config ARCH_SPARSEMEM_ENABLE
1249 def_bool y
1250 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1251 select SPARSEMEM_STATIC if X86_32
1252 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1254 config ARCH_SPARSEMEM_DEFAULT
1255 def_bool y
1256 depends on X86_64
1258 config ARCH_SELECT_MEMORY_MODEL
1259 def_bool y
1260 depends on ARCH_SPARSEMEM_ENABLE
1262 config ARCH_MEMORY_PROBE
1263 def_bool X86_64
1264 depends on MEMORY_HOTPLUG
1266 config ARCH_PROC_KCORE_TEXT
1267 def_bool y
1268 depends on X86_64 && PROC_KCORE
1270 config ILLEGAL_POINTER_VALUE
1271 hex
1272 default 0 if X86_32
1273 default 0xdead000000000000 if X86_64
1275 source "mm/Kconfig"
1277 config HIGHPTE
1278 bool "Allocate 3rd-level pagetables from highmem"
1279 depends on HIGHMEM
1280 ---help---
1281 The VM uses one page table entry for each page of physical memory.
1282 For systems with a lot of RAM, this can be wasteful of precious
1283 low memory. Setting this option will put user-space page table
1284 entries in high memory.
1286 config X86_CHECK_BIOS_CORRUPTION
1287 bool "Check for low memory corruption"
1288 ---help---
1289 Periodically check for memory corruption in low memory, which
1290 is suspected to be caused by BIOS. Even when enabled in the
1291 configuration, it is disabled at runtime. Enable it by
1292 setting "memory_corruption_check=1" on the kernel command
1293 line. By default it scans the low 64k of memory every 60
1294 seconds; see the memory_corruption_check_size and
1295 memory_corruption_check_period parameters in
1296 Documentation/kernel-parameters.txt to adjust this.
1298 When enabled with the default parameters, this option has
1299 almost no overhead, as it reserves a relatively small amount
1300 of memory and scans it infrequently. It both detects corruption
1301 and prevents it from affecting the running system.
1303 It is, however, intended as a diagnostic tool; if repeatable
1304 BIOS-originated corruption always affects the same memory,
1305 you can use memmap= to prevent the kernel from using that
1306 memory.
1308 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1309 bool "Set the default setting of memory_corruption_check"
1310 depends on X86_CHECK_BIOS_CORRUPTION
1311 default y
1312 ---help---
1313 Set whether the default state of memory_corruption_check is
1314 on or off.
1316 config X86_RESERVE_LOW
1317 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1318 default 64
1319 range 4 640
1320 ---help---
1321 Specify the amount of low memory to reserve for the BIOS.
1323 The first page contains BIOS data structures that the kernel
1324 must not use, so that page must always be reserved.
1326 By default we reserve the first 64K of physical RAM, as a
1327 number of BIOSes are known to corrupt that memory range
1328 during events such as suspend/resume or monitor cable
1329 insertion, so it must not be used by the kernel.
1331 You can set this to 4 if you are absolutely sure that you
1332 trust the BIOS to get all its memory reservations and usages
1333 right. If you know your BIOS have problems beyond the
1334 default 64K area, you can set this to 640 to avoid using the
1335 entire low memory range.
1337 If you have doubts about the BIOS (e.g. suspend/resume does
1338 not work or there's kernel crashes after certain hardware
1339 hotplug events) then you might want to enable
1340 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1341 typical corruption patterns.
1343 Leave this to the default value of 64 if you are unsure.
1345 config MATH_EMULATION
1346 bool
1347 prompt "Math emulation" if X86_32
1348 ---help---
1349 Linux can emulate a math coprocessor (used for floating point
1350 operations) if you don't have one. 486DX and Pentium processors have
1351 a math coprocessor built in, 486SX and 386 do not, unless you added
1352 a 487DX or 387, respectively. (The messages during boot time can
1353 give you some hints here ["man dmesg"].) Everyone needs either a
1354 coprocessor or this emulation.
1356 If you don't have a math coprocessor, you need to say Y here; if you
1357 say Y here even though you have a coprocessor, the coprocessor will
1358 be used nevertheless. (This behavior can be changed with the kernel
1359 command line option "no387", which comes handy if your coprocessor
1360 is broken. Try "man bootparam" or see the documentation of your boot
1361 loader (lilo or loadlin) about how to pass options to the kernel at
1362 boot time.) This means that it is a good idea to say Y here if you
1363 intend to use this kernel on different machines.
1365 More information about the internals of the Linux math coprocessor
1366 emulation can be found in <file:arch/x86/math-emu/README>.
1368 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1369 kernel, it won't hurt.
1371 config MTRR
1372 def_bool y
1373 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1374 ---help---
1375 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1376 the Memory Type Range Registers (MTRRs) may be used to control
1377 processor access to memory ranges. This is most useful if you have
1378 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1379 allows bus write transfers to be combined into a larger transfer
1380 before bursting over the PCI/AGP bus. This can increase performance
1381 of image write operations 2.5 times or more. Saying Y here creates a
1382 /proc/mtrr file which may be used to manipulate your processor's
1383 MTRRs. Typically the X server should use this.
1385 This code has a reasonably generic interface so that similar
1386 control registers on other processors can be easily supported
1387 as well:
1389 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1390 Registers (ARRs) which provide a similar functionality to MTRRs. For
1391 these, the ARRs are used to emulate the MTRRs.
1392 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1393 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1394 write-combining. All of these processors are supported by this code
1395 and it makes sense to say Y here if you have one of them.
1397 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1398 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1399 can lead to all sorts of problems, so it's good to say Y here.
1401 You can safely say Y even if your machine doesn't have MTRRs, you'll
1402 just add about 9 KB to your kernel.
1404 See <file:Documentation/x86/mtrr.txt> for more information.
1406 config MTRR_SANITIZER
1407 def_bool y
1408 prompt "MTRR cleanup support"
1409 depends on MTRR
1410 ---help---
1411 Convert MTRR layout from continuous to discrete, so X drivers can
1412 add writeback entries.
1414 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1415 The largest mtrr entry size for a continuous block can be set with
1416 mtrr_chunk_size.
1418 If unsure, say Y.
1420 config MTRR_SANITIZER_ENABLE_DEFAULT
1421 int "MTRR cleanup enable value (0-1)"
1422 range 0 1
1423 default "0"
1424 depends on MTRR_SANITIZER
1425 ---help---
1426 Enable mtrr cleanup default value
1428 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1429 int "MTRR cleanup spare reg num (0-7)"
1430 range 0 7
1431 default "1"
1432 depends on MTRR_SANITIZER
1433 ---help---
1434 mtrr cleanup spare entries default, it can be changed via
1435 mtrr_spare_reg_nr=N on the kernel command line.
1437 config X86_PAT
1438 def_bool y
1439 prompt "x86 PAT support" if EXPERT
1440 depends on MTRR
1441 ---help---
1442 Use PAT attributes to setup page level cache control.
1444 PATs are the modern equivalents of MTRRs and are much more
1445 flexible than MTRRs.
1447 Say N here if you see bootup problems (boot crash, boot hang,
1448 spontaneous reboots) or a non-working video driver.
1450 If unsure, say Y.
1452 config ARCH_USES_PG_UNCACHED
1453 def_bool y
1454 depends on X86_PAT
1456 config EFI
1457 bool "EFI runtime service support"
1458 depends on ACPI
1459 ---help---
1460 This enables the kernel to use EFI runtime services that are
1461 available (such as the EFI variable services).
1463 This option is only useful on systems that have EFI firmware.
1464 In addition, you should use the latest ELILO loader available
1465 at <http://elilo.sourceforge.net> in order to take advantage
1466 of EFI runtime services. However, even with this option, the
1467 resultant kernel should continue to boot on existing non-EFI
1468 platforms.
1470 config SECCOMP
1471 def_bool y
1472 prompt "Enable seccomp to safely compute untrusted bytecode"
1473 ---help---
1474 This kernel feature is useful for number crunching applications
1475 that may need to compute untrusted bytecode during their
1476 execution. By using pipes or other transports made available to
1477 the process as file descriptors supporting the read/write
1478 syscalls, it's possible to isolate those applications in
1479 their own address space using seccomp. Once seccomp is
1480 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1481 and the task is only allowed to execute a few safe syscalls
1482 defined by each seccomp mode.
1484 If unsure, say Y. Only embedded should say N here.
1486 config CC_STACKPROTECTOR
1487 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1488 ---help---
1489 This option turns on the -fstack-protector GCC feature. This
1490 feature puts, at the beginning of functions, a canary value on
1491 the stack just before the return address, and validates
1492 the value just before actually returning. Stack based buffer
1493 overflows (that need to overwrite this return address) now also
1494 overwrite the canary, which gets detected and the attack is then
1495 neutralized via a kernel panic.
1497 This feature requires gcc version 4.2 or above, or a distribution
1498 gcc with the feature backported. Older versions are automatically
1499 detected and for those versions, this configuration option is
1500 ignored. (and a warning is printed during bootup)
1502 source kernel/Kconfig.hz
1504 config KEXEC
1505 bool "kexec system call"
1506 ---help---
1507 kexec is a system call that implements the ability to shutdown your
1508 current kernel, and to start another kernel. It is like a reboot
1509 but it is independent of the system firmware. And like a reboot
1510 you can start any kernel with it, not just Linux.
1512 The name comes from the similarity to the exec system call.
1514 It is an ongoing process to be certain the hardware in a machine
1515 is properly shutdown, so do not be surprised if this code does not
1516 initially work for you. It may help to enable device hotplugging
1517 support. As of this writing the exact hardware interface is
1518 strongly in flux, so no good recommendation can be made.
1520 config CRASH_DUMP
1521 bool "kernel crash dumps"
1522 depends on X86_64 || (X86_32 && HIGHMEM)
1523 ---help---
1524 Generate crash dump after being started by kexec.
1525 This should be normally only set in special crash dump kernels
1526 which are loaded in the main kernel with kexec-tools into
1527 a specially reserved region and then later executed after
1528 a crash by kdump/kexec. The crash dump kernel must be compiled
1529 to a memory address not used by the main kernel or BIOS using
1530 PHYSICAL_START, or it must be built as a relocatable image
1531 (CONFIG_RELOCATABLE=y).
1532 For more details see Documentation/kdump/kdump.txt
1534 config KEXEC_JUMP
1535 bool "kexec jump (EXPERIMENTAL)"
1536 depends on EXPERIMENTAL
1537 depends on KEXEC && HIBERNATION
1538 ---help---
1539 Jump between original kernel and kexeced kernel and invoke
1540 code in physical address mode via KEXEC
1542 config PHYSICAL_START
1543 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1544 default "0x1000000"
1545 ---help---
1546 This gives the physical address where the kernel is loaded.
1548 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1549 bzImage will decompress itself to above physical address and
1550 run from there. Otherwise, bzImage will run from the address where
1551 it has been loaded by the boot loader and will ignore above physical
1552 address.
1554 In normal kdump cases one does not have to set/change this option
1555 as now bzImage can be compiled as a completely relocatable image
1556 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1557 address. This option is mainly useful for the folks who don't want
1558 to use a bzImage for capturing the crash dump and want to use a
1559 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1560 to be specifically compiled to run from a specific memory area
1561 (normally a reserved region) and this option comes handy.
1563 So if you are using bzImage for capturing the crash dump,
1564 leave the value here unchanged to 0x1000000 and set
1565 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1566 for capturing the crash dump change this value to start of
1567 the reserved region. In other words, it can be set based on
1568 the "X" value as specified in the "crashkernel=YM@XM"
1569 command line boot parameter passed to the panic-ed
1570 kernel. Please take a look at Documentation/kdump/kdump.txt
1571 for more details about crash dumps.
1573 Usage of bzImage for capturing the crash dump is recommended as
1574 one does not have to build two kernels. Same kernel can be used
1575 as production kernel and capture kernel. Above option should have
1576 gone away after relocatable bzImage support is introduced. But it
1577 is present because there are users out there who continue to use
1578 vmlinux for dump capture. This option should go away down the
1579 line.
1581 Don't change this unless you know what you are doing.
1583 config RELOCATABLE
1584 bool "Build a relocatable kernel"
1585 default y
1586 ---help---
1587 This builds a kernel image that retains relocation information
1588 so it can be loaded someplace besides the default 1MB.
1589 The relocations tend to make the kernel binary about 10% larger,
1590 but are discarded at runtime.
1592 One use is for the kexec on panic case where the recovery kernel
1593 must live at a different physical address than the primary
1594 kernel.
1596 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1597 it has been loaded at and the compile time physical address
1598 (CONFIG_PHYSICAL_START) is ignored.
1600 # Relocation on x86-32 needs some additional build support
1601 config X86_NEED_RELOCS
1602 def_bool y
1603 depends on X86_32 && RELOCATABLE
1605 config PHYSICAL_ALIGN
1606 hex "Alignment value to which kernel should be aligned" if X86_32
1607 default "0x1000000"
1608 range 0x2000 0x1000000
1609 ---help---
1610 This value puts the alignment restrictions on physical address
1611 where kernel is loaded and run from. Kernel is compiled for an
1612 address which meets above alignment restriction.
1614 If bootloader loads the kernel at a non-aligned address and
1615 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1616 address aligned to above value and run from there.
1618 If bootloader loads the kernel at a non-aligned address and
1619 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1620 load address and decompress itself to the address it has been
1621 compiled for and run from there. The address for which kernel is
1622 compiled already meets above alignment restrictions. Hence the
1623 end result is that kernel runs from a physical address meeting
1624 above alignment restrictions.
1626 Don't change this unless you know what you are doing.
1628 config HOTPLUG_CPU
1629 bool "Support for hot-pluggable CPUs"
1630 depends on SMP && HOTPLUG
1631 ---help---
1632 Say Y here to allow turning CPUs off and on. CPUs can be
1633 controlled through /sys/devices/system/cpu.
1634 ( Note: power management support will enable this option
1635 automatically on SMP systems. )
1636 Say N if you want to disable CPU hotplug.
1638 config COMPAT_VDSO
1639 def_bool y
1640 prompt "Compat VDSO support"
1641 depends on X86_32 || IA32_EMULATION
1642 ---help---
1643 Map the 32-bit VDSO to the predictable old-style address too.
1645 Say N here if you are running a sufficiently recent glibc
1646 version (2.3.3 or later), to remove the high-mapped
1647 VDSO mapping and to exclusively use the randomized VDSO.
1649 If unsure, say Y.
1651 config CMDLINE_BOOL
1652 bool "Built-in kernel command line"
1653 ---help---
1654 Allow for specifying boot arguments to the kernel at
1655 build time. On some systems (e.g. embedded ones), it is
1656 necessary or convenient to provide some or all of the
1657 kernel boot arguments with the kernel itself (that is,
1658 to not rely on the boot loader to provide them.)
1660 To compile command line arguments into the kernel,
1661 set this option to 'Y', then fill in the
1662 the boot arguments in CONFIG_CMDLINE.
1664 Systems with fully functional boot loaders (i.e. non-embedded)
1665 should leave this option set to 'N'.
1667 config CMDLINE
1668 string "Built-in kernel command string"
1669 depends on CMDLINE_BOOL
1670 default ""
1671 ---help---
1672 Enter arguments here that should be compiled into the kernel
1673 image and used at boot time. If the boot loader provides a
1674 command line at boot time, it is appended to this string to
1675 form the full kernel command line, when the system boots.
1677 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1678 change this behavior.
1680 In most cases, the command line (whether built-in or provided
1681 by the boot loader) should specify the device for the root
1682 file system.
1684 config CMDLINE_OVERRIDE
1685 bool "Built-in command line overrides boot loader arguments"
1686 depends on CMDLINE_BOOL
1687 ---help---
1688 Set this option to 'Y' to have the kernel ignore the boot loader
1689 command line, and use ONLY the built-in command line.
1691 This is used to work around broken boot loaders. This should
1692 be set to 'N' under normal conditions.
1694 endmenu
1696 config ARCH_ENABLE_MEMORY_HOTPLUG
1697 def_bool y
1698 depends on X86_64 || (X86_32 && HIGHMEM)
1700 config ARCH_ENABLE_MEMORY_HOTREMOVE
1701 def_bool y
1702 depends on MEMORY_HOTPLUG
1704 config USE_PERCPU_NUMA_NODE_ID
1705 def_bool y
1706 depends on NUMA
1708 menu "Power management and ACPI options"
1710 config ARCH_HIBERNATION_HEADER
1711 def_bool y
1712 depends on X86_64 && HIBERNATION
1714 source "kernel/power/Kconfig"
1716 source "drivers/acpi/Kconfig"
1718 source "drivers/sfi/Kconfig"
1720 config X86_APM_BOOT
1721 def_bool y
1722 depends on APM || APM_MODULE
1724 menuconfig APM
1725 tristate "APM (Advanced Power Management) BIOS support"
1726 depends on X86_32 && PM_SLEEP
1727 ---help---
1728 APM is a BIOS specification for saving power using several different
1729 techniques. This is mostly useful for battery powered laptops with
1730 APM compliant BIOSes. If you say Y here, the system time will be
1731 reset after a RESUME operation, the /proc/apm device will provide
1732 battery status information, and user-space programs will receive
1733 notification of APM "events" (e.g. battery status change).
1735 If you select "Y" here, you can disable actual use of the APM
1736 BIOS by passing the "apm=off" option to the kernel at boot time.
1738 Note that the APM support is almost completely disabled for
1739 machines with more than one CPU.
1741 In order to use APM, you will need supporting software. For location
1742 and more information, read <file:Documentation/power/pm.txt> and the
1743 Battery Powered Linux mini-HOWTO, available from
1744 <http://www.tldp.org/docs.html#howto>.
1746 This driver does not spin down disk drives (see the hdparm(8)
1747 manpage ("man 8 hdparm") for that), and it doesn't turn off
1748 VESA-compliant "green" monitors.
1750 This driver does not support the TI 4000M TravelMate and the ACER
1751 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1752 desktop machines also don't have compliant BIOSes, and this driver
1753 may cause those machines to panic during the boot phase.
1755 Generally, if you don't have a battery in your machine, there isn't
1756 much point in using this driver and you should say N. If you get
1757 random kernel OOPSes or reboots that don't seem to be related to
1758 anything, try disabling/enabling this option (or disabling/enabling
1759 APM in your BIOS).
1761 Some other things you should try when experiencing seemingly random,
1762 "weird" problems:
1764 1) make sure that you have enough swap space and that it is
1765 enabled.
1766 2) pass the "no-hlt" option to the kernel
1767 3) switch on floating point emulation in the kernel and pass
1768 the "no387" option to the kernel
1769 4) pass the "floppy=nodma" option to the kernel
1770 5) pass the "mem=4M" option to the kernel (thereby disabling
1771 all but the first 4 MB of RAM)
1772 6) make sure that the CPU is not over clocked.
1773 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1774 8) disable the cache from your BIOS settings
1775 9) install a fan for the video card or exchange video RAM
1776 10) install a better fan for the CPU
1777 11) exchange RAM chips
1778 12) exchange the motherboard.
1780 To compile this driver as a module, choose M here: the
1781 module will be called apm.
1783 if APM
1785 config APM_IGNORE_USER_SUSPEND
1786 bool "Ignore USER SUSPEND"
1787 ---help---
1788 This option will ignore USER SUSPEND requests. On machines with a
1789 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1790 series notebooks, it is necessary to say Y because of a BIOS bug.
1792 config APM_DO_ENABLE
1793 bool "Enable PM at boot time"
1794 ---help---
1795 Enable APM features at boot time. From page 36 of the APM BIOS
1796 specification: "When disabled, the APM BIOS does not automatically
1797 power manage devices, enter the Standby State, enter the Suspend
1798 State, or take power saving steps in response to CPU Idle calls."
1799 This driver will make CPU Idle calls when Linux is idle (unless this
1800 feature is turned off -- see "Do CPU IDLE calls", below). This
1801 should always save battery power, but more complicated APM features
1802 will be dependent on your BIOS implementation. You may need to turn
1803 this option off if your computer hangs at boot time when using APM
1804 support, or if it beeps continuously instead of suspending. Turn
1805 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1806 T400CDT. This is off by default since most machines do fine without
1807 this feature.
1809 config APM_CPU_IDLE
1810 bool "Make CPU Idle calls when idle"
1811 ---help---
1812 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1813 On some machines, this can activate improved power savings, such as
1814 a slowed CPU clock rate, when the machine is idle. These idle calls
1815 are made after the idle loop has run for some length of time (e.g.,
1816 333 mS). On some machines, this will cause a hang at boot time or
1817 whenever the CPU becomes idle. (On machines with more than one CPU,
1818 this option does nothing.)
1820 config APM_DISPLAY_BLANK
1821 bool "Enable console blanking using APM"
1822 ---help---
1823 Enable console blanking using the APM. Some laptops can use this to
1824 turn off the LCD backlight when the screen blanker of the Linux
1825 virtual console blanks the screen. Note that this is only used by
1826 the virtual console screen blanker, and won't turn off the backlight
1827 when using the X Window system. This also doesn't have anything to
1828 do with your VESA-compliant power-saving monitor. Further, this
1829 option doesn't work for all laptops -- it might not turn off your
1830 backlight at all, or it might print a lot of errors to the console,
1831 especially if you are using gpm.
1833 config APM_ALLOW_INTS
1834 bool "Allow interrupts during APM BIOS calls"
1835 ---help---
1836 Normally we disable external interrupts while we are making calls to
1837 the APM BIOS as a measure to lessen the effects of a badly behaving
1838 BIOS implementation. The BIOS should reenable interrupts if it
1839 needs to. Unfortunately, some BIOSes do not -- especially those in
1840 many of the newer IBM Thinkpads. If you experience hangs when you
1841 suspend, try setting this to Y. Otherwise, say N.
1843 endif # APM
1845 source "drivers/cpufreq/Kconfig"
1847 source "drivers/cpuidle/Kconfig"
1849 source "drivers/idle/Kconfig"
1851 endmenu
1854 menu "Bus options (PCI etc.)"
1856 config PCI
1857 bool "PCI support"
1858 default y
1859 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1860 ---help---
1861 Find out whether you have a PCI motherboard. PCI is the name of a
1862 bus system, i.e. the way the CPU talks to the other stuff inside
1863 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1864 VESA. If you have PCI, say Y, otherwise N.
1866 choice
1867 prompt "PCI access mode"
1868 depends on X86_32 && PCI
1869 default PCI_GOANY
1870 ---help---
1871 On PCI systems, the BIOS can be used to detect the PCI devices and
1872 determine their configuration. However, some old PCI motherboards
1873 have BIOS bugs and may crash if this is done. Also, some embedded
1874 PCI-based systems don't have any BIOS at all. Linux can also try to
1875 detect the PCI hardware directly without using the BIOS.
1877 With this option, you can specify how Linux should detect the
1878 PCI devices. If you choose "BIOS", the BIOS will be used,
1879 if you choose "Direct", the BIOS won't be used, and if you
1880 choose "MMConfig", then PCI Express MMCONFIG will be used.
1881 If you choose "Any", the kernel will try MMCONFIG, then the
1882 direct access method and falls back to the BIOS if that doesn't
1883 work. If unsure, go with the default, which is "Any".
1885 config PCI_GOBIOS
1886 bool "BIOS"
1888 config PCI_GOMMCONFIG
1889 bool "MMConfig"
1891 config PCI_GODIRECT
1892 bool "Direct"
1894 config PCI_GOOLPC
1895 bool "OLPC XO-1"
1896 depends on OLPC
1898 config PCI_GOANY
1899 bool "Any"
1901 endchoice
1903 config PCI_BIOS
1904 def_bool y
1905 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1907 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1908 config PCI_DIRECT
1909 def_bool y
1910 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1912 config PCI_MMCONFIG
1913 def_bool y
1914 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
1916 config PCI_OLPC
1917 def_bool y
1918 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1920 config PCI_XEN
1921 def_bool y
1922 depends on PCI && XEN
1923 select SWIOTLB_XEN
1925 config PCI_DOMAINS
1926 def_bool y
1927 depends on PCI
1929 config PCI_MMCONFIG
1930 bool "Support mmconfig PCI config space access"
1931 depends on X86_64 && PCI && ACPI
1933 config PCI_CNB20LE_QUIRK
1934 bool "Read CNB20LE Host Bridge Windows" if EXPERT
1935 default n
1936 depends on PCI && EXPERIMENTAL
1937 help
1938 Read the PCI windows out of the CNB20LE host bridge. This allows
1939 PCI hotplug to work on systems with the CNB20LE chipset which do
1940 not have ACPI.
1942 There's no public spec for this chipset, and this functionality
1943 is known to be incomplete.
1945 You should say N unless you know you need this.
1947 config DMAR
1948 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1949 depends on PCI_MSI && ACPI && EXPERIMENTAL
1950 help
1951 DMA remapping (DMAR) devices support enables independent address
1952 translations for Direct Memory Access (DMA) from devices.
1953 These DMA remapping devices are reported via ACPI tables
1954 and include PCI device scope covered by these DMA
1955 remapping devices.
1957 config DMAR_DEFAULT_ON
1958 def_bool y
1959 prompt "Enable DMA Remapping Devices by default"
1960 depends on DMAR
1961 help
1962 Selecting this option will enable a DMAR device at boot time if
1963 one is found. If this option is not selected, DMAR support can
1964 be enabled by passing intel_iommu=on to the kernel. It is
1965 recommended you say N here while the DMAR code remains
1966 experimental.
1968 config DMAR_BROKEN_GFX_WA
1969 bool "Workaround broken graphics drivers (going away soon)"
1970 depends on DMAR && BROKEN
1971 ---help---
1972 Current Graphics drivers tend to use physical address
1973 for DMA and avoid using DMA APIs. Setting this config
1974 option permits the IOMMU driver to set a unity map for
1975 all the OS-visible memory. Hence the driver can continue
1976 to use physical addresses for DMA, at least until this
1977 option is removed in the 2.6.32 kernel.
1979 config DMAR_FLOPPY_WA
1980 def_bool y
1981 depends on DMAR
1982 ---help---
1983 Floppy disk drivers are known to bypass DMA API calls
1984 thereby failing to work when IOMMU is enabled. This
1985 workaround will setup a 1:1 mapping for the first
1986 16MiB to make floppy (an ISA device) work.
1988 config INTR_REMAP
1989 bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1990 depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
1991 ---help---
1992 Supports Interrupt remapping for IO-APIC and MSI devices.
1993 To use x2apic mode in the CPU's which support x2APIC enhancements or
1994 to support platforms with CPU's having > 8 bit APIC ID, say Y.
1996 source "drivers/pci/pcie/Kconfig"
1998 source "drivers/pci/Kconfig"
2000 # x86_64 have no ISA slots, but can have ISA-style DMA.
2001 config ISA_DMA_API
2002 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2003 default y
2004 help
2005 Enables ISA-style DMA support for devices requiring such controllers.
2006 If unsure, say Y.
2008 if X86_32
2010 config ISA
2011 bool "ISA support"
2012 ---help---
2013 Find out whether you have ISA slots on your motherboard. ISA is the
2014 name of a bus system, i.e. the way the CPU talks to the other stuff
2015 inside your box. Other bus systems are PCI, EISA, MicroChannel
2016 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2017 newer boards don't support it. If you have ISA, say Y, otherwise N.
2019 config EISA
2020 bool "EISA support"
2021 depends on ISA
2022 ---help---
2023 The Extended Industry Standard Architecture (EISA) bus was
2024 developed as an open alternative to the IBM MicroChannel bus.
2026 The EISA bus provided some of the features of the IBM MicroChannel
2027 bus while maintaining backward compatibility with cards made for
2028 the older ISA bus. The EISA bus saw limited use between 1988 and
2029 1995 when it was made obsolete by the PCI bus.
2031 Say Y here if you are building a kernel for an EISA-based machine.
2033 Otherwise, say N.
2035 source "drivers/eisa/Kconfig"
2037 config MCA
2038 bool "MCA support"
2039 ---help---
2040 MicroChannel Architecture is found in some IBM PS/2 machines and
2041 laptops. It is a bus system similar to PCI or ISA. See
2042 <file:Documentation/mca.txt> (and especially the web page given
2043 there) before attempting to build an MCA bus kernel.
2045 source "drivers/mca/Kconfig"
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.
2055 If compiled as a module, the driver is named scx200.
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.
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 ---help---
2075 Add support for detecting the unique features of the OLPC
2076 XO hardware.
2078 config OLPC_XO1
2079 tristate "OLPC XO-1 support"
2080 depends on OLPC && MFD_CS5535
2081 ---help---
2082 Add support for non-essential features of the OLPC XO-1 laptop.
2084 endif # X86_32
2086 config AMD_NB
2087 def_bool y
2088 depends on CPU_SUP_AMD && PCI
2090 source "drivers/pcmcia/Kconfig"
2092 source "drivers/pci/hotplug/Kconfig"
2094 config RAPIDIO
2095 bool "RapidIO support"
2096 depends on PCI
2097 default n
2098 help
2099 If you say Y here, the kernel will include drivers and
2100 infrastructure code to support RapidIO interconnect devices.
2102 source "drivers/rapidio/Kconfig"
2104 endmenu
2107 menu "Executable file formats / Emulations"
2109 source "fs/Kconfig.binfmt"
2111 config IA32_EMULATION
2112 bool "IA32 Emulation"
2113 depends on X86_64
2114 select COMPAT_BINFMT_ELF
2115 ---help---
2116 Include code to run 32-bit programs under a 64-bit kernel. You should
2117 likely turn this on, unless you're 100% sure that you don't have any
2118 32-bit programs left.
2120 config IA32_AOUT
2121 tristate "IA32 a.out support"
2122 depends on IA32_EMULATION
2123 ---help---
2124 Support old a.out binaries in the 32bit emulation.
2126 config COMPAT
2127 def_bool y
2128 depends on IA32_EMULATION
2130 config COMPAT_FOR_U64_ALIGNMENT
2131 def_bool COMPAT
2132 depends on X86_64
2134 config SYSVIPC_COMPAT
2135 def_bool y
2136 depends on COMPAT && SYSVIPC
2138 config KEYS_COMPAT
2139 bool
2140 depends on COMPAT && KEYS
2141 default y
2143 endmenu
2146 config HAVE_ATOMIC_IOMAP
2147 def_bool y
2148 depends on X86_32
2150 config HAVE_TEXT_POKE_SMP
2151 bool
2152 select STOP_MACHINE if SMP
2154 source "net/Kconfig"
2156 source "drivers/Kconfig"
2158 source "drivers/firmware/Kconfig"
2160 source "fs/Kconfig"
2162 source "arch/x86/Kconfig.debug"
2164 source "security/Kconfig"
2166 source "crypto/Kconfig"
2168 source "arch/x86/kvm/Kconfig"
2170 source "lib/Kconfig"