| blob | 3ed5ad92b029a09bb6c30823ae3472c14107e831 |
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
12 config X86_64
13 def_bool 64BIT
15 ### Arch settings
16 config X86
17 def_bool y
18 select HAVE_AOUT if X86_32
19 select HAVE_READQ
20 select HAVE_WRITEQ
21 select HAVE_UNSTABLE_SCHED_CLOCK
22 select HAVE_IDE
23 select HAVE_OPROFILE
24 select HAVE_PERF_EVENTS
25 select HAVE_IRQ_WORK
26 select HAVE_IOREMAP_PROT
27 select HAVE_KPROBES
28 select HAVE_MEMBLOCK
29 select ARCH_WANT_OPTIONAL_GPIOLIB
30 select ARCH_WANT_FRAME_POINTERS
31 select HAVE_DMA_ATTRS
32 select HAVE_KRETPROBES
33 select HAVE_OPTPROBES
34 select HAVE_FTRACE_MCOUNT_RECORD
35 select HAVE_C_RECORDMCOUNT
36 select HAVE_DYNAMIC_FTRACE
37 select HAVE_FUNCTION_TRACER
38 select HAVE_FUNCTION_GRAPH_TRACER
39 select HAVE_FUNCTION_GRAPH_FP_TEST
40 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
41 select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
42 select HAVE_SYSCALL_TRACEPOINTS
43 select HAVE_KVM
44 select HAVE_ARCH_KGDB
45 select HAVE_ARCH_TRACEHOOK
46 select HAVE_GENERIC_DMA_COHERENT if X86_32
47 select HAVE_EFFICIENT_UNALIGNED_ACCESS
48 select USER_STACKTRACE_SUPPORT
49 select HAVE_REGS_AND_STACK_ACCESS_API
50 select HAVE_DMA_API_DEBUG
51 select HAVE_KERNEL_GZIP
52 select HAVE_KERNEL_BZIP2
53 select HAVE_KERNEL_LZMA
54 select HAVE_KERNEL_XZ
55 select HAVE_KERNEL_LZO
56 select HAVE_HW_BREAKPOINT
57 select HAVE_MIXED_BREAKPOINTS_REGS
58 select PERF_EVENTS
59 select HAVE_PERF_EVENTS_NMI
60 select ANON_INODES
61 select HAVE_ARCH_KMEMCHECK
62 select HAVE_USER_RETURN_NOTIFIER
63 select HAVE_ARCH_JUMP_LABEL
64 select HAVE_TEXT_POKE_SMP
65 select HAVE_GENERIC_HARDIRQS
66 select HAVE_SPARSE_IRQ
67 select GENERIC_IRQ_PROBE
68 select GENERIC_PENDING_IRQ if SMP
69 select USE_GENERIC_SMP_HELPERS if SMP
71 config INSTRUCTION_DECODER
72 def_bool (KPROBES || PERF_EVENTS)
74 config OUTPUT_FORMAT
75 string
76 default "elf32-i386" if X86_32
77 default "elf64-x86-64" if X86_64
79 config ARCH_DEFCONFIG
80 string
81 default "arch/x86/configs/i386_defconfig" if X86_32
82 default "arch/x86/configs/x86_64_defconfig" if X86_64
84 config GENERIC_CMOS_UPDATE
85 def_bool y
87 config CLOCKSOURCE_WATCHDOG
88 def_bool y
90 config GENERIC_CLOCKEVENTS
91 def_bool y
93 config GENERIC_CLOCKEVENTS_BROADCAST
94 def_bool y
95 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
97 config LOCKDEP_SUPPORT
98 def_bool y
100 config STACKTRACE_SUPPORT
101 def_bool y
103 config HAVE_LATENCYTOP_SUPPORT
104 def_bool y
106 config MMU
107 def_bool y
109 config ZONE_DMA
110 def_bool y
112 config SBUS
113 bool
115 config NEED_DMA_MAP_STATE
116 def_bool (X86_64 || DMAR || DMA_API_DEBUG)
118 config NEED_SG_DMA_LENGTH
119 def_bool y
121 config GENERIC_ISA_DMA
122 def_bool y
124 config GENERIC_IOMAP
125 def_bool y
127 config GENERIC_BUG
128 def_bool y
129 depends on BUG
130 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
132 config GENERIC_BUG_RELATIVE_POINTERS
133 bool
135 config GENERIC_HWEIGHT
136 def_bool y
138 config GENERIC_GPIO
139 bool
141 config ARCH_MAY_HAVE_PC_FDC
142 def_bool y
144 config RWSEM_GENERIC_SPINLOCK
145 def_bool !X86_XADD
147 config RWSEM_XCHGADD_ALGORITHM
148 def_bool X86_XADD
150 config ARCH_HAS_CPU_IDLE_WAIT
151 def_bool y
153 config GENERIC_CALIBRATE_DELAY
154 def_bool y
156 config GENERIC_TIME_VSYSCALL
157 bool
158 default X86_64
160 config ARCH_HAS_CPU_RELAX
161 def_bool y
163 config ARCH_HAS_DEFAULT_IDLE
164 def_bool y
166 config ARCH_HAS_CACHE_LINE_SIZE
167 def_bool y
169 config HAVE_SETUP_PER_CPU_AREA
170 def_bool y
172 config NEED_PER_CPU_EMBED_FIRST_CHUNK
173 def_bool y
175 config NEED_PER_CPU_PAGE_FIRST_CHUNK
176 def_bool y
178 config HAVE_CPUMASK_OF_CPU_MAP
179 def_bool X86_64_SMP
181 config ARCH_HIBERNATION_POSSIBLE
182 def_bool y
184 config ARCH_SUSPEND_POSSIBLE
185 def_bool y
187 config ZONE_DMA32
188 bool
189 default X86_64
191 config ARCH_POPULATES_NODE_MAP
192 def_bool y
194 config AUDIT_ARCH
195 bool
196 default X86_64
198 config ARCH_SUPPORTS_OPTIMIZED_INLINING
199 def_bool y
201 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
202 def_bool y
204 config HAVE_INTEL_TXT
205 def_bool y
206 depends on EXPERIMENTAL && DMAR && ACPI
208 config X86_32_SMP
209 def_bool y
210 depends on X86_32 && SMP
212 config X86_64_SMP
213 def_bool y
214 depends on X86_64 && SMP
216 config X86_HT
217 def_bool y
218 depends on SMP
220 config X86_TRAMPOLINE
221 def_bool y
222 depends on SMP || (64BIT && ACPI_SLEEP)
224 config X86_32_LAZY_GS
225 def_bool y
226 depends on X86_32 && !CC_STACKPROTECTOR
228 config ARCH_HWEIGHT_CFLAGS
229 string
230 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
231 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
233 config KTIME_SCALAR
234 def_bool X86_32
236 config ARCH_CPU_PROBE_RELEASE
237 def_bool y
238 depends on HOTPLUG_CPU
240 source "init/Kconfig"
241 source "kernel/Kconfig.freezer"
243 menu "Processor type and features"
245 source "kernel/time/Kconfig"
247 config SMP
248 bool "Symmetric multi-processing support"
249 ---help---
250 This enables support for systems with more than one CPU. If you have
251 a system with only one CPU, like most personal computers, say N. If
252 you have a system with more than one CPU, say Y.
254 If you say N here, the kernel will run on single and multiprocessor
255 machines, but will use only one CPU of a multiprocessor machine. If
256 you say Y here, the kernel will run on many, but not all,
257 singleprocessor machines. On a singleprocessor machine, the kernel
258 will run faster if you say N here.
260 Note that if you say Y here and choose architecture "586" or
261 "Pentium" under "Processor family", the kernel will not work on 486
262 architectures. Similarly, multiprocessor kernels for the "PPro"
263 architecture may not work on all Pentium based boards.
265 People using multiprocessor machines who say Y here should also say
266 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
267 Management" code will be disabled if you say Y here.
269 See also <file:Documentation/i386/IO-APIC.txt>,
270 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
271 <http://www.tldp.org/docs.html#howto>.
273 If you don't know what to do here, say N.
275 config X86_X2APIC
276 bool "Support x2apic"
277 depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
278 ---help---
279 This enables x2apic support on CPUs that have this feature.
281 This allows 32-bit apic IDs (so it can support very large systems),
282 and accesses the local apic via MSRs not via mmio.
284 If you don't know what to do here, say N.
286 config X86_MPPARSE
287 bool "Enable MPS table" if ACPI
288 default y
289 depends on X86_LOCAL_APIC
290 ---help---
291 For old smp systems that do not have proper acpi support. Newer systems
292 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
294 config X86_BIGSMP
295 bool "Support for big SMP systems with more than 8 CPUs"
296 depends on X86_32 && SMP
297 ---help---
298 This option is needed for the systems that have more than 8 CPUs
300 if X86_32
301 config X86_EXTENDED_PLATFORM
302 bool "Support for extended (non-PC) x86 platforms"
303 default y
304 ---help---
305 If you disable this option then the kernel will only support
306 standard PC platforms. (which covers the vast majority of
307 systems out there.)
309 If you enable this option then you'll be able to select support
310 for the following (non-PC) 32 bit x86 platforms:
311 AMD Elan
312 NUMAQ (IBM/Sequent)
313 RDC R-321x SoC
314 SGI 320/540 (Visual Workstation)
315 Summit/EXA (IBM x440)
316 Unisys ES7000 IA32 series
317 Moorestown MID devices
319 If you have one of these systems, or if you want to build a
320 generic distribution kernel, say Y here - otherwise say N.
321 endif
323 if X86_64
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.)
332 If you enable this option then you'll be able to select support
333 for the following (non-PC) 64 bit x86 platforms:
334 ScaleMP vSMP
335 SGI Ultraviolet
337 If you have one of these systems, or if you want to build a
338 generic distribution kernel, say Y here - otherwise say N.
339 endif
340 # This is an alphabetically sorted list of 64 bit extended platforms
341 # Please maintain the alphabetic order if and when there are additions
343 config X86_VSMP
344 bool "ScaleMP vSMP"
345 select PARAVIRT_GUEST
346 select PARAVIRT
347 depends on X86_64 && PCI
348 depends on X86_EXTENDED_PLATFORM
349 ---help---
350 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
351 supposed to run on these EM64T-based machines. Only choose this option
352 if you have one of these machines.
354 config X86_UV
355 bool "SGI Ultraviolet"
356 depends on X86_64
357 depends on X86_EXTENDED_PLATFORM
358 depends on NUMA
359 depends on X86_X2APIC
360 ---help---
361 This option is needed in order to support SGI Ultraviolet systems.
362 If you don't have one of these, you should say N here.
364 # Following is an alphabetically sorted list of 32 bit extended platforms
365 # Please maintain the alphabetic order if and when there are additions
367 config X86_ELAN
368 bool "AMD Elan"
369 depends on X86_32
370 depends on X86_EXTENDED_PLATFORM
371 ---help---
372 Select this for an AMD Elan processor.
374 Do not use this option for K6/Athlon/Opteron processors!
376 If unsure, choose "PC-compatible" instead.
378 config X86_INTEL_CE
379 bool "CE4100 TV platform"
380 depends on PCI
381 depends on PCI_GODIRECT
382 depends on X86_32
383 depends on X86_EXTENDED_PLATFORM
384 select X86_REBOOTFIXUPS
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 embedded 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 EMBEDDED
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 EMBEDDED
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 depends on X86_64 && PCI && ACPI
691 ---help---
692 With this option you can enable support for AMD IOMMU hardware in
693 your system. An IOMMU is a hardware component which provides
694 remapping of DMA memory accesses from devices. With an AMD IOMMU you
695 can isolate the the DMA memory of different devices and protect the
696 system from misbehaving device drivers or hardware.
698 You can find out if your system has an AMD IOMMU if you look into
699 your BIOS for an option to enable it or if you have an IVRS ACPI
700 table.
702 config AMD_IOMMU_STATS
703 bool "Export AMD IOMMU statistics to debugfs"
704 depends on AMD_IOMMU
705 select DEBUG_FS
706 ---help---
707 This option enables code in the AMD IOMMU driver to collect various
708 statistics about whats happening in the driver and exports that
709 information to userspace via debugfs.
710 If unsure, say N.
712 # need this always selected by IOMMU for the VIA workaround
713 config SWIOTLB
714 def_bool y if X86_64
715 ---help---
716 Support for software bounce buffers used on x86-64 systems
717 which don't have a hardware IOMMU (e.g. the current generation
718 of Intel's x86-64 CPUs). Using this PCI devices which can only
719 access 32-bits of memory can be used on systems with more than
720 3 GB of memory. If unsure, say Y.
722 config IOMMU_HELPER
723 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
725 config IOMMU_API
726 def_bool (AMD_IOMMU || DMAR)
728 config MAXSMP
729 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
730 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
731 select CPUMASK_OFFSTACK
732 ---help---
733 Enable maximum number of CPUS and NUMA Nodes for this architecture.
734 If unsure, say N.
736 config NR_CPUS
737 int "Maximum number of CPUs" if SMP && !MAXSMP
738 range 2 8 if SMP && X86_32 && !X86_BIGSMP
739 range 2 512 if SMP && !MAXSMP
740 default "1" if !SMP
741 default "4096" if MAXSMP
742 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
743 default "8" if SMP
744 ---help---
745 This allows you to specify the maximum number of CPUs which this
746 kernel will support. The maximum supported value is 512 and the
747 minimum value which makes sense is 2.
749 This is purely to save memory - each supported CPU adds
750 approximately eight kilobytes to the kernel image.
752 config SCHED_SMT
753 bool "SMT (Hyperthreading) scheduler support"
754 depends on X86_HT
755 ---help---
756 SMT scheduler support improves the CPU scheduler's decision making
757 when dealing with Intel Pentium 4 chips with HyperThreading at a
758 cost of slightly increased overhead in some places. If unsure say
759 N here.
761 config SCHED_MC
762 def_bool y
763 prompt "Multi-core scheduler support"
764 depends on X86_HT
765 ---help---
766 Multi-core scheduler support improves the CPU scheduler's decision
767 making when dealing with multi-core CPU chips at a cost of slightly
768 increased overhead in some places. If unsure say N here.
770 config IRQ_TIME_ACCOUNTING
771 bool "Fine granularity task level IRQ time accounting"
772 default n
773 ---help---
774 Select this option to enable fine granularity task irq time
775 accounting. This is done by reading a timestamp on each
776 transitions between softirq and hardirq state, so there can be a
777 small performance impact.
779 If in doubt, say N here.
781 source "kernel/Kconfig.preempt"
783 config X86_UP_APIC
784 bool "Local APIC support on uniprocessors"
785 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
786 ---help---
787 A local APIC (Advanced Programmable Interrupt Controller) is an
788 integrated interrupt controller in the CPU. If you have a single-CPU
789 system which has a processor with a local APIC, you can say Y here to
790 enable and use it. If you say Y here even though your machine doesn't
791 have a local APIC, then the kernel will still run with no slowdown at
792 all. The local APIC supports CPU-generated self-interrupts (timer,
793 performance counters), and the NMI watchdog which detects hard
794 lockups.
796 config X86_UP_IOAPIC
797 bool "IO-APIC support on uniprocessors"
798 depends on X86_UP_APIC
799 ---help---
800 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
801 SMP-capable replacement for PC-style interrupt controllers. Most
802 SMP systems and many recent uniprocessor systems have one.
804 If you have a single-CPU system with an IO-APIC, you can say Y here
805 to use it. If you say Y here even though your machine doesn't have
806 an IO-APIC, then the kernel will still run with no slowdown at all.
808 config X86_LOCAL_APIC
809 def_bool y
810 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
812 config X86_IO_APIC
813 def_bool y
814 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
816 config X86_VISWS_APIC
817 def_bool y
818 depends on X86_32 && X86_VISWS
820 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
821 bool "Reroute for broken boot IRQs"
822 depends on X86_IO_APIC
823 ---help---
824 This option enables a workaround that fixes a source of
825 spurious interrupts. This is recommended when threaded
826 interrupt handling is used on systems where the generation of
827 superfluous "boot interrupts" cannot be disabled.
829 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
830 entry in the chipset's IO-APIC is masked (as, e.g. the RT
831 kernel does during interrupt handling). On chipsets where this
832 boot IRQ generation cannot be disabled, this workaround keeps
833 the original IRQ line masked so that only the equivalent "boot
834 IRQ" is delivered to the CPUs. The workaround also tells the
835 kernel to set up the IRQ handler on the boot IRQ line. In this
836 way only one interrupt is delivered to the kernel. Otherwise
837 the spurious second interrupt may cause the kernel to bring
838 down (vital) interrupt lines.
840 Only affects "broken" chipsets. Interrupt sharing may be
841 increased on these systems.
843 config X86_MCE
844 bool "Machine Check / overheating reporting"
845 ---help---
846 Machine Check support allows the processor to notify the
847 kernel if it detects a problem (e.g. overheating, data corruption).
848 The action the kernel takes depends on the severity of the problem,
849 ranging from warning messages to halting the machine.
851 config X86_MCE_INTEL
852 def_bool y
853 prompt "Intel MCE features"
854 depends on X86_MCE && X86_LOCAL_APIC
855 ---help---
856 Additional support for intel specific MCE features such as
857 the thermal monitor.
859 config X86_MCE_AMD
860 def_bool y
861 prompt "AMD MCE features"
862 depends on X86_MCE && X86_LOCAL_APIC
863 ---help---
864 Additional support for AMD specific MCE features such as
865 the DRAM Error Threshold.
867 config X86_ANCIENT_MCE
868 bool "Support for old Pentium 5 / WinChip machine checks"
869 depends on X86_32 && X86_MCE
870 ---help---
871 Include support for machine check handling on old Pentium 5 or WinChip
872 systems. These typically need to be enabled explicitely on the command
873 line.
875 config X86_MCE_THRESHOLD
876 depends on X86_MCE_AMD || X86_MCE_INTEL
877 def_bool y
879 config X86_MCE_INJECT
880 depends on X86_MCE
881 tristate "Machine check injector support"
882 ---help---
883 Provide support for injecting machine checks for testing purposes.
884 If you don't know what a machine check is and you don't do kernel
885 QA it is safe to say n.
887 config X86_THERMAL_VECTOR
888 def_bool y
889 depends on X86_MCE_INTEL
891 config VM86
892 bool "Enable VM86 support" if EMBEDDED
893 default y
894 depends on X86_32
895 ---help---
896 This option is required by programs like DOSEMU to run 16-bit legacy
897 code on X86 processors. It also may be needed by software like
898 XFree86 to initialize some video cards via BIOS. Disabling this
899 option saves about 6k.
901 config TOSHIBA
902 tristate "Toshiba Laptop support"
903 depends on X86_32
904 ---help---
905 This adds a driver to safely access the System Management Mode of
906 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
907 not work on models with a Phoenix BIOS. The System Management Mode
908 is used to set the BIOS and power saving options on Toshiba portables.
910 For information on utilities to make use of this driver see the
911 Toshiba Linux utilities web site at:
912 <http://www.buzzard.org.uk/toshiba/>.
914 Say Y if you intend to run this kernel on a Toshiba portable.
915 Say N otherwise.
917 config I8K
918 tristate "Dell laptop support"
919 ---help---
920 This adds a driver to safely access the System Management Mode
921 of the CPU on the Dell Inspiron 8000. The System Management Mode
922 is used to read cpu temperature and cooling fan status and to
923 control the fans on the I8K portables.
925 This driver has been tested only on the Inspiron 8000 but it may
926 also work with other Dell laptops. You can force loading on other
927 models by passing the parameter `force=1' to the module. Use at
928 your own risk.
930 For information on utilities to make use of this driver see the
931 I8K Linux utilities web site at:
932 <http://people.debian.org/~dz/i8k/>
934 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
935 Say N otherwise.
937 config X86_REBOOTFIXUPS
938 bool "Enable X86 board specific fixups for reboot"
939 depends on X86_32
940 ---help---
941 This enables chipset and/or board specific fixups to be done
942 in order to get reboot to work correctly. This is only needed on
943 some combinations of hardware and BIOS. The symptom, for which
944 this config is intended, is when reboot ends with a stalled/hung
945 system.
947 Currently, the only fixup is for the Geode machines using
948 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
950 Say Y if you want to enable the fixup. Currently, it's safe to
951 enable this option even if you don't need it.
952 Say N otherwise.
954 config MICROCODE
955 tristate "/dev/cpu/microcode - microcode support"
956 select FW_LOADER
957 ---help---
958 If you say Y here, you will be able to update the microcode on
959 certain Intel and AMD processors. The Intel support is for the
960 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
961 Pentium 4, Xeon etc. The AMD support is for family 0x10 and
962 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
963 You will obviously need the actual microcode binary data itself
964 which is not shipped with the Linux kernel.
966 This option selects the general module only, you need to select
967 at least one vendor specific module as well.
969 To compile this driver as a module, choose M here: the
970 module will be called microcode.
972 config MICROCODE_INTEL
973 bool "Intel microcode patch loading support"
974 depends on MICROCODE
975 default MICROCODE
976 select FW_LOADER
977 ---help---
978 This options enables microcode patch loading support for Intel
979 processors.
981 For latest news and information on obtaining all the required
982 Intel ingredients for this driver, check:
983 <http://www.urbanmyth.org/microcode/>.
985 config MICROCODE_AMD
986 bool "AMD microcode patch loading support"
987 depends on MICROCODE
988 select FW_LOADER
989 ---help---
990 If you select this option, microcode patch loading support for AMD
991 processors will be enabled.
993 config MICROCODE_OLD_INTERFACE
994 def_bool y
995 depends on MICROCODE
997 config X86_MSR
998 tristate "/dev/cpu/*/msr - Model-specific register support"
999 ---help---
1000 This device gives privileged processes access to the x86
1001 Model-Specific Registers (MSRs). It is a character device with
1002 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1003 MSR accesses are directed to a specific CPU on multi-processor
1004 systems.
1006 config X86_CPUID
1007 tristate "/dev/cpu/*/cpuid - CPU information support"
1008 ---help---
1009 This device gives processes access to the x86 CPUID instruction to
1010 be executed on a specific processor. It is a character device
1011 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1012 /dev/cpu/31/cpuid.
1014 choice
1015 prompt "High Memory Support"
1016 default HIGHMEM64G if X86_NUMAQ
1017 default HIGHMEM4G
1018 depends on X86_32
1020 config NOHIGHMEM
1021 bool "off"
1022 depends on !X86_NUMAQ
1023 ---help---
1024 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1025 However, the address space of 32-bit x86 processors is only 4
1026 Gigabytes large. That means that, if you have a large amount of
1027 physical memory, not all of it can be "permanently mapped" by the
1028 kernel. The physical memory that's not permanently mapped is called
1029 "high memory".
1031 If you are compiling a kernel which will never run on a machine with
1032 more than 1 Gigabyte total physical RAM, answer "off" here (default
1033 choice and suitable for most users). This will result in a "3GB/1GB"
1034 split: 3GB are mapped so that each process sees a 3GB virtual memory
1035 space and the remaining part of the 4GB virtual memory space is used
1036 by the kernel to permanently map as much physical memory as
1037 possible.
1039 If the machine has between 1 and 4 Gigabytes physical RAM, then
1040 answer "4GB" here.
1042 If more than 4 Gigabytes is used then answer "64GB" here. This
1043 selection turns Intel PAE (Physical Address Extension) mode on.
1044 PAE implements 3-level paging on IA32 processors. PAE is fully
1045 supported by Linux, PAE mode is implemented on all recent Intel
1046 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1047 then the kernel will not boot on CPUs that don't support PAE!
1049 The actual amount of total physical memory will either be
1050 auto detected or can be forced by using a kernel command line option
1051 such as "mem=256M". (Try "man bootparam" or see the documentation of
1052 your boot loader (lilo or loadlin) about how to pass options to the
1053 kernel at boot time.)
1055 If unsure, say "off".
1057 config HIGHMEM4G
1058 bool "4GB"
1059 depends on !X86_NUMAQ
1060 ---help---
1061 Select this if you have a 32-bit processor and between 1 and 4
1062 gigabytes of physical RAM.
1064 config HIGHMEM64G
1065 bool "64GB"
1066 depends on !M386 && !M486
1067 select X86_PAE
1068 ---help---
1069 Select this if you have a 32-bit processor and more than 4
1070 gigabytes of physical RAM.
1072 endchoice
1074 choice
1075 depends on EXPERIMENTAL
1076 prompt "Memory split" if EMBEDDED
1077 default VMSPLIT_3G
1078 depends on X86_32
1079 ---help---
1080 Select the desired split between kernel and user memory.
1082 If the address range available to the kernel is less than the
1083 physical memory installed, the remaining memory will be available
1084 as "high memory". Accessing high memory is a little more costly
1085 than low memory, as it needs to be mapped into the kernel first.
1086 Note that increasing the kernel address space limits the range
1087 available to user programs, making the address space there
1088 tighter. Selecting anything other than the default 3G/1G split
1089 will also likely make your kernel incompatible with binary-only
1090 kernel modules.
1092 If you are not absolutely sure what you are doing, leave this
1093 option alone!
1095 config VMSPLIT_3G
1096 bool "3G/1G user/kernel split"
1097 config VMSPLIT_3G_OPT
1098 depends on !X86_PAE
1099 bool "3G/1G user/kernel split (for full 1G low memory)"
1100 config VMSPLIT_2G
1101 bool "2G/2G user/kernel split"
1102 config VMSPLIT_2G_OPT
1103 depends on !X86_PAE
1104 bool "2G/2G user/kernel split (for full 2G low memory)"
1105 config VMSPLIT_1G
1106 bool "1G/3G user/kernel split"
1107 endchoice
1109 config PAGE_OFFSET
1110 hex
1111 default 0xB0000000 if VMSPLIT_3G_OPT
1112 default 0x80000000 if VMSPLIT_2G
1113 default 0x78000000 if VMSPLIT_2G_OPT
1114 default 0x40000000 if VMSPLIT_1G
1115 default 0xC0000000
1116 depends on X86_32
1118 config HIGHMEM
1119 def_bool y
1120 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1122 config X86_PAE
1123 bool "PAE (Physical Address Extension) Support"
1124 depends on X86_32 && !HIGHMEM4G
1125 ---help---
1126 PAE is required for NX support, and furthermore enables
1127 larger swapspace support for non-overcommit purposes. It
1128 has the cost of more pagetable lookup overhead, and also
1129 consumes more pagetable space per process.
1131 config ARCH_PHYS_ADDR_T_64BIT
1132 def_bool X86_64 || X86_PAE
1134 config ARCH_DMA_ADDR_T_64BIT
1135 def_bool X86_64 || HIGHMEM64G
1137 config DIRECT_GBPAGES
1138 bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
1139 default y
1140 depends on X86_64
1141 ---help---
1142 Allow the kernel linear mapping to use 1GB pages on CPUs that
1143 support it. This can improve the kernel's performance a tiny bit by
1144 reducing TLB pressure. If in doubt, say "Y".
1146 # Common NUMA Features
1147 config NUMA
1148 bool "Numa Memory Allocation and Scheduler Support"
1149 depends on SMP
1150 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1151 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1152 ---help---
1153 Enable NUMA (Non Uniform Memory Access) support.
1155 The kernel will try to allocate memory used by a CPU on the
1156 local memory controller of the CPU and add some more
1157 NUMA awareness to the kernel.
1159 For 64-bit this is recommended if the system is Intel Core i7
1160 (or later), AMD Opteron, or EM64T NUMA.
1162 For 32-bit this is only needed on (rare) 32-bit-only platforms
1163 that support NUMA topologies, such as NUMAQ / Summit, or if you
1164 boot a 32-bit kernel on a 64-bit NUMA platform.
1166 Otherwise, you should say N.
1168 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1169 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1171 config AMD_NUMA
1172 def_bool y
1173 prompt "Old style AMD Opteron NUMA detection"
1174 depends on X86_64 && NUMA && PCI
1175 ---help---
1176 Enable AMD NUMA node topology detection. You should say Y here if
1177 you have a multi processor AMD system. This uses an old method to
1178 read the NUMA configuration directly from the builtin Northbridge
1179 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1180 which also takes priority if both are compiled in.
1182 config X86_64_ACPI_NUMA
1183 def_bool y
1184 prompt "ACPI NUMA detection"
1185 depends on X86_64 && NUMA && ACPI && PCI
1186 select ACPI_NUMA
1187 ---help---
1188 Enable ACPI SRAT based node topology detection.
1190 # Some NUMA nodes have memory ranges that span
1191 # other nodes. Even though a pfn is valid and
1192 # between a node's start and end pfns, it may not
1193 # reside on that node. See memmap_init_zone()
1194 # for details.
1195 config NODES_SPAN_OTHER_NODES
1196 def_bool y
1197 depends on X86_64_ACPI_NUMA
1199 config NUMA_EMU
1200 bool "NUMA emulation"
1201 depends on X86_64 && NUMA
1202 ---help---
1203 Enable NUMA emulation. A flat machine will be split
1204 into virtual nodes when booted with "numa=fake=N", where N is the
1205 number of nodes. This is only useful for debugging.
1207 config NODES_SHIFT
1208 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1209 range 1 10
1210 default "10" if MAXSMP
1211 default "6" if X86_64
1212 default "4" if X86_NUMAQ
1213 default "3"
1214 depends on NEED_MULTIPLE_NODES
1215 ---help---
1216 Specify the maximum number of NUMA Nodes available on the target
1217 system. Increases memory reserved to accommodate various tables.
1219 config HAVE_ARCH_BOOTMEM
1220 def_bool y
1221 depends on X86_32 && NUMA
1223 config ARCH_HAVE_MEMORY_PRESENT
1224 def_bool y
1225 depends on X86_32 && DISCONTIGMEM
1227 config NEED_NODE_MEMMAP_SIZE
1228 def_bool y
1229 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1231 config HAVE_ARCH_ALLOC_REMAP
1232 def_bool y
1233 depends on X86_32 && NUMA
1235 config ARCH_FLATMEM_ENABLE
1236 def_bool y
1237 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
1239 config ARCH_DISCONTIGMEM_ENABLE
1240 def_bool y
1241 depends on NUMA && X86_32
1243 config ARCH_DISCONTIGMEM_DEFAULT
1244 def_bool y
1245 depends on NUMA && X86_32
1247 config ARCH_PROC_KCORE_TEXT
1248 def_bool y
1249 depends on X86_64 && PROC_KCORE
1251 config ARCH_SPARSEMEM_DEFAULT
1252 def_bool y
1253 depends on X86_64
1255 config ARCH_SPARSEMEM_ENABLE
1256 def_bool y
1257 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1258 select SPARSEMEM_STATIC if X86_32
1259 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1261 config ARCH_SELECT_MEMORY_MODEL
1262 def_bool y
1263 depends on ARCH_SPARSEMEM_ENABLE
1265 config ARCH_MEMORY_PROBE
1266 def_bool X86_64
1267 depends on MEMORY_HOTPLUG
1269 config ILLEGAL_POINTER_VALUE
1270 hex
1271 default 0 if X86_32
1272 default 0xdead000000000000 if X86_64
1274 source "mm/Kconfig"
1276 config HIGHPTE
1277 bool "Allocate 3rd-level pagetables from highmem"
1278 depends on HIGHMEM
1279 ---help---
1280 The VM uses one page table entry for each page of physical memory.
1281 For systems with a lot of RAM, this can be wasteful of precious
1282 low memory. Setting this option will put user-space page table
1283 entries in high memory.
1285 config X86_CHECK_BIOS_CORRUPTION
1286 bool "Check for low memory corruption"
1287 ---help---
1288 Periodically check for memory corruption in low memory, which
1289 is suspected to be caused by BIOS. Even when enabled in the
1290 configuration, it is disabled at runtime. Enable it by
1291 setting "memory_corruption_check=1" on the kernel command
1292 line. By default it scans the low 64k of memory every 60
1293 seconds; see the memory_corruption_check_size and
1294 memory_corruption_check_period parameters in
1295 Documentation/kernel-parameters.txt to adjust this.
1297 When enabled with the default parameters, this option has
1298 almost no overhead, as it reserves a relatively small amount
1299 of memory and scans it infrequently. It both detects corruption
1300 and prevents it from affecting the running system.
1302 It is, however, intended as a diagnostic tool; if repeatable
1303 BIOS-originated corruption always affects the same memory,
1304 you can use memmap= to prevent the kernel from using that
1305 memory.
1307 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1308 bool "Set the default setting of memory_corruption_check"
1309 depends on X86_CHECK_BIOS_CORRUPTION
1310 default y
1311 ---help---
1312 Set whether the default state of memory_corruption_check is
1313 on or off.
1315 config X86_RESERVE_LOW
1316 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1317 default 64
1318 range 4 640
1319 ---help---
1320 Specify the amount of low memory to reserve for the BIOS.
1322 The first page contains BIOS data structures that the kernel
1323 must not use, so that page must always be reserved.
1325 By default we reserve the first 64K of physical RAM, as a
1326 number of BIOSes are known to corrupt that memory range
1327 during events such as suspend/resume or monitor cable
1328 insertion, so it must not be used by the kernel.
1330 You can set this to 4 if you are absolutely sure that you
1331 trust the BIOS to get all its memory reservations and usages
1332 right. If you know your BIOS have problems beyond the
1333 default 64K area, you can set this to 640 to avoid using the
1334 entire low memory range.
1336 If you have doubts about the BIOS (e.g. suspend/resume does
1337 not work or there's kernel crashes after certain hardware
1338 hotplug events) then you might want to enable
1339 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1340 typical corruption patterns.
1342 Leave this to the default value of 64 if you are unsure.
1344 config MATH_EMULATION
1345 bool
1346 prompt "Math emulation" if X86_32
1347 ---help---
1348 Linux can emulate a math coprocessor (used for floating point
1349 operations) if you don't have one. 486DX and Pentium processors have
1350 a math coprocessor built in, 486SX and 386 do not, unless you added
1351 a 487DX or 387, respectively. (The messages during boot time can
1352 give you some hints here ["man dmesg"].) Everyone needs either a
1353 coprocessor or this emulation.
1355 If you don't have a math coprocessor, you need to say Y here; if you
1356 say Y here even though you have a coprocessor, the coprocessor will
1357 be used nevertheless. (This behavior can be changed with the kernel
1358 command line option "no387", which comes handy if your coprocessor
1359 is broken. Try "man bootparam" or see the documentation of your boot
1360 loader (lilo or loadlin) about how to pass options to the kernel at
1361 boot time.) This means that it is a good idea to say Y here if you
1362 intend to use this kernel on different machines.
1364 More information about the internals of the Linux math coprocessor
1365 emulation can be found in <file:arch/x86/math-emu/README>.
1367 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1368 kernel, it won't hurt.
1370 config MTRR
1371 def_bool y
1372 prompt "MTRR (Memory Type Range Register) support" if EMBEDDED
1373 ---help---
1374 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1375 the Memory Type Range Registers (MTRRs) may be used to control
1376 processor access to memory ranges. This is most useful if you have
1377 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1378 allows bus write transfers to be combined into a larger transfer
1379 before bursting over the PCI/AGP bus. This can increase performance
1380 of image write operations 2.5 times or more. Saying Y here creates a
1381 /proc/mtrr file which may be used to manipulate your processor's
1382 MTRRs. Typically the X server should use this.
1384 This code has a reasonably generic interface so that similar
1385 control registers on other processors can be easily supported
1386 as well:
1388 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1389 Registers (ARRs) which provide a similar functionality to MTRRs. For
1390 these, the ARRs are used to emulate the MTRRs.
1391 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1392 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1393 write-combining. All of these processors are supported by this code
1394 and it makes sense to say Y here if you have one of them.
1396 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1397 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1398 can lead to all sorts of problems, so it's good to say Y here.
1400 You can safely say Y even if your machine doesn't have MTRRs, you'll
1401 just add about 9 KB to your kernel.
1403 See <file:Documentation/x86/mtrr.txt> for more information.
1405 config MTRR_SANITIZER
1406 def_bool y
1407 prompt "MTRR cleanup support"
1408 depends on MTRR
1409 ---help---
1410 Convert MTRR layout from continuous to discrete, so X drivers can
1411 add writeback entries.
1413 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1414 The largest mtrr entry size for a continuous block can be set with
1415 mtrr_chunk_size.
1417 If unsure, say Y.
1419 config MTRR_SANITIZER_ENABLE_DEFAULT
1420 int "MTRR cleanup enable value (0-1)"
1421 range 0 1
1422 default "0"
1423 depends on MTRR_SANITIZER
1424 ---help---
1425 Enable mtrr cleanup default value
1427 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1428 int "MTRR cleanup spare reg num (0-7)"
1429 range 0 7
1430 default "1"
1431 depends on MTRR_SANITIZER
1432 ---help---
1433 mtrr cleanup spare entries default, it can be changed via
1434 mtrr_spare_reg_nr=N on the kernel command line.
1436 config X86_PAT
1437 def_bool y
1438 prompt "x86 PAT support" if EMBEDDED
1439 depends on MTRR
1440 ---help---
1441 Use PAT attributes to setup page level cache control.
1443 PATs are the modern equivalents of MTRRs and are much more
1444 flexible than MTRRs.
1446 Say N here if you see bootup problems (boot crash, boot hang,
1447 spontaneous reboots) or a non-working video driver.
1449 If unsure, say Y.
1451 config ARCH_USES_PG_UNCACHED
1452 def_bool y
1453 depends on X86_PAT
1455 config EFI
1456 bool "EFI runtime service support"
1457 depends on ACPI
1458 ---help---
1459 This enables the kernel to use EFI runtime services that are
1460 available (such as the EFI variable services).
1462 This option is only useful on systems that have EFI firmware.
1463 In addition, you should use the latest ELILO loader available
1464 at <http://elilo.sourceforge.net> in order to take advantage
1465 of EFI runtime services. However, even with this option, the
1466 resultant kernel should continue to boot on existing non-EFI
1467 platforms.
1469 config SECCOMP
1470 def_bool y
1471 prompt "Enable seccomp to safely compute untrusted bytecode"
1472 ---help---
1473 This kernel feature is useful for number crunching applications
1474 that may need to compute untrusted bytecode during their
1475 execution. By using pipes or other transports made available to
1476 the process as file descriptors supporting the read/write
1477 syscalls, it's possible to isolate those applications in
1478 their own address space using seccomp. Once seccomp is
1479 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1480 and the task is only allowed to execute a few safe syscalls
1481 defined by each seccomp mode.
1483 If unsure, say Y. Only embedded should say N here.
1485 config CC_STACKPROTECTOR
1486 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1487 ---help---
1488 This option turns on the -fstack-protector GCC feature. This
1489 feature puts, at the beginning of functions, a canary value on
1490 the stack just before the return address, and validates
1491 the value just before actually returning. Stack based buffer
1492 overflows (that need to overwrite this return address) now also
1493 overwrite the canary, which gets detected and the attack is then
1494 neutralized via a kernel panic.
1496 This feature requires gcc version 4.2 or above, or a distribution
1497 gcc with the feature backported. Older versions are automatically
1498 detected and for those versions, this configuration option is
1499 ignored. (and a warning is printed during bootup)
1501 source kernel/Kconfig.hz
1503 config KEXEC
1504 bool "kexec system call"
1505 ---help---
1506 kexec is a system call that implements the ability to shutdown your
1507 current kernel, and to start another kernel. It is like a reboot
1508 but it is independent of the system firmware. And like a reboot
1509 you can start any kernel with it, not just Linux.
1511 The name comes from the similarity to the exec system call.
1513 It is an ongoing process to be certain the hardware in a machine
1514 is properly shutdown, so do not be surprised if this code does not
1515 initially work for you. It may help to enable device hotplugging
1516 support. As of this writing the exact hardware interface is
1517 strongly in flux, so no good recommendation can be made.
1519 config CRASH_DUMP
1520 bool "kernel crash dumps"
1521 depends on X86_64 || (X86_32 && HIGHMEM)
1522 ---help---
1523 Generate crash dump after being started by kexec.
1524 This should be normally only set in special crash dump kernels
1525 which are loaded in the main kernel with kexec-tools into
1526 a specially reserved region and then later executed after
1527 a crash by kdump/kexec. The crash dump kernel must be compiled
1528 to a memory address not used by the main kernel or BIOS using
1529 PHYSICAL_START, or it must be built as a relocatable image
1530 (CONFIG_RELOCATABLE=y).
1531 For more details see Documentation/kdump/kdump.txt
1533 config KEXEC_JUMP
1534 bool "kexec jump (EXPERIMENTAL)"
1535 depends on EXPERIMENTAL
1536 depends on KEXEC && HIBERNATION
1537 ---help---
1538 Jump between original kernel and kexeced kernel and invoke
1539 code in physical address mode via KEXEC
1541 config PHYSICAL_START
1542 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1543 default "0x1000000"
1544 ---help---
1545 This gives the physical address where the kernel is loaded.
1547 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1548 bzImage will decompress itself to above physical address and
1549 run from there. Otherwise, bzImage will run from the address where
1550 it has been loaded by the boot loader and will ignore above physical
1551 address.
1553 In normal kdump cases one does not have to set/change this option
1554 as now bzImage can be compiled as a completely relocatable image
1555 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1556 address. This option is mainly useful for the folks who don't want
1557 to use a bzImage for capturing the crash dump and want to use a
1558 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1559 to be specifically compiled to run from a specific memory area
1560 (normally a reserved region) and this option comes handy.
1562 So if you are using bzImage for capturing the crash dump,
1563 leave the value here unchanged to 0x1000000 and set
1564 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1565 for capturing the crash dump change this value to start of
1566 the reserved region. In other words, it can be set based on
1567 the "X" value as specified in the "crashkernel=YM@XM"
1568 command line boot parameter passed to the panic-ed
1569 kernel. Please take a look at Documentation/kdump/kdump.txt
1570 for more details about crash dumps.
1572 Usage of bzImage for capturing the crash dump is recommended as
1573 one does not have to build two kernels. Same kernel can be used
1574 as production kernel and capture kernel. Above option should have
1575 gone away after relocatable bzImage support is introduced. But it
1576 is present because there are users out there who continue to use
1577 vmlinux for dump capture. This option should go away down the
1578 line.
1580 Don't change this unless you know what you are doing.
1582 config RELOCATABLE
1583 bool "Build a relocatable kernel"
1584 default y
1585 ---help---
1586 This builds a kernel image that retains relocation information
1587 so it can be loaded someplace besides the default 1MB.
1588 The relocations tend to make the kernel binary about 10% larger,
1589 but are discarded at runtime.
1591 One use is for the kexec on panic case where the recovery kernel
1592 must live at a different physical address than the primary
1593 kernel.
1595 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1596 it has been loaded at and the compile time physical address
1597 (CONFIG_PHYSICAL_START) is ignored.
1599 # Relocation on x86-32 needs some additional build support
1600 config X86_NEED_RELOCS
1601 def_bool y
1602 depends on X86_32 && RELOCATABLE
1604 config PHYSICAL_ALIGN
1605 hex "Alignment value to which kernel should be aligned" if X86_32
1606 default "0x1000000"
1607 range 0x2000 0x1000000
1608 ---help---
1609 This value puts the alignment restrictions on physical address
1610 where kernel is loaded and run from. Kernel is compiled for an
1611 address which meets above alignment restriction.
1613 If bootloader loads the kernel at a non-aligned address and
1614 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1615 address aligned to above value and run from there.
1617 If bootloader loads the kernel at a non-aligned address and
1618 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1619 load address and decompress itself to the address it has been
1620 compiled for and run from there. The address for which kernel is
1621 compiled already meets above alignment restrictions. Hence the
1622 end result is that kernel runs from a physical address meeting
1623 above alignment restrictions.
1625 Don't change this unless you know what you are doing.
1627 config HOTPLUG_CPU
1628 bool "Support for hot-pluggable CPUs"
1629 depends on SMP && HOTPLUG
1630 ---help---
1631 Say Y here to allow turning CPUs off and on. CPUs can be
1632 controlled through /sys/devices/system/cpu.
1633 ( Note: power management support will enable this option
1634 automatically on SMP systems. )
1635 Say N if you want to disable CPU hotplug.
1637 config COMPAT_VDSO
1638 def_bool y
1639 prompt "Compat VDSO support"
1640 depends on X86_32 || IA32_EMULATION
1641 ---help---
1642 Map the 32-bit VDSO to the predictable old-style address too.
1644 Say N here if you are running a sufficiently recent glibc
1645 version (2.3.3 or later), to remove the high-mapped
1646 VDSO mapping and to exclusively use the randomized VDSO.
1648 If unsure, say Y.
1650 config CMDLINE_BOOL
1651 bool "Built-in kernel command line"
1652 ---help---
1653 Allow for specifying boot arguments to the kernel at
1654 build time. On some systems (e.g. embedded ones), it is
1655 necessary or convenient to provide some or all of the
1656 kernel boot arguments with the kernel itself (that is,
1657 to not rely on the boot loader to provide them.)
1659 To compile command line arguments into the kernel,
1660 set this option to 'Y', then fill in the
1661 the boot arguments in CONFIG_CMDLINE.
1663 Systems with fully functional boot loaders (i.e. non-embedded)
1664 should leave this option set to 'N'.
1666 config CMDLINE
1667 string "Built-in kernel command string"
1668 depends on CMDLINE_BOOL
1669 default ""
1670 ---help---
1671 Enter arguments here that should be compiled into the kernel
1672 image and used at boot time. If the boot loader provides a
1673 command line at boot time, it is appended to this string to
1674 form the full kernel command line, when the system boots.
1676 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1677 change this behavior.
1679 In most cases, the command line (whether built-in or provided
1680 by the boot loader) should specify the device for the root
1681 file system.
1683 config CMDLINE_OVERRIDE
1684 bool "Built-in command line overrides boot loader arguments"
1685 depends on CMDLINE_BOOL
1686 ---help---
1687 Set this option to 'Y' to have the kernel ignore the boot loader
1688 command line, and use ONLY the built-in command line.
1690 This is used to work around broken boot loaders. This should
1691 be set to 'N' under normal conditions.
1693 endmenu
1695 config ARCH_ENABLE_MEMORY_HOTPLUG
1696 def_bool y
1697 depends on X86_64 || (X86_32 && HIGHMEM)
1699 config ARCH_ENABLE_MEMORY_HOTREMOVE
1700 def_bool y
1701 depends on MEMORY_HOTPLUG
1703 config HAVE_ARCH_EARLY_PFN_TO_NID
1704 def_bool X86_64
1705 depends on NUMA
1707 config USE_PERCPU_NUMA_NODE_ID
1708 def_bool X86_64
1709 depends on NUMA
1711 menu "Power management and ACPI options"
1713 config ARCH_HIBERNATION_HEADER
1714 def_bool y
1715 depends on X86_64 && HIBERNATION
1717 source "kernel/power/Kconfig"
1719 source "drivers/acpi/Kconfig"
1721 source "drivers/sfi/Kconfig"
1723 config X86_APM_BOOT
1724 def_bool y
1725 depends on APM || APM_MODULE
1727 menuconfig APM
1728 tristate "APM (Advanced Power Management) BIOS support"
1729 depends on X86_32 && PM_SLEEP
1730 ---help---
1731 APM is a BIOS specification for saving power using several different
1732 techniques. This is mostly useful for battery powered laptops with
1733 APM compliant BIOSes. If you say Y here, the system time will be
1734 reset after a RESUME operation, the /proc/apm device will provide
1735 battery status information, and user-space programs will receive
1736 notification of APM "events" (e.g. battery status change).
1738 If you select "Y" here, you can disable actual use of the APM
1739 BIOS by passing the "apm=off" option to the kernel at boot time.
1741 Note that the APM support is almost completely disabled for
1742 machines with more than one CPU.
1744 In order to use APM, you will need supporting software. For location
1745 and more information, read <file:Documentation/power/pm.txt> and the
1746 Battery Powered Linux mini-HOWTO, available from
1747 <http://www.tldp.org/docs.html#howto>.
1749 This driver does not spin down disk drives (see the hdparm(8)
1750 manpage ("man 8 hdparm") for that), and it doesn't turn off
1751 VESA-compliant "green" monitors.
1753 This driver does not support the TI 4000M TravelMate and the ACER
1754 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1755 desktop machines also don't have compliant BIOSes, and this driver
1756 may cause those machines to panic during the boot phase.
1758 Generally, if you don't have a battery in your machine, there isn't
1759 much point in using this driver and you should say N. If you get
1760 random kernel OOPSes or reboots that don't seem to be related to
1761 anything, try disabling/enabling this option (or disabling/enabling
1762 APM in your BIOS).
1764 Some other things you should try when experiencing seemingly random,
1765 "weird" problems:
1767 1) make sure that you have enough swap space and that it is
1768 enabled.
1769 2) pass the "no-hlt" option to the kernel
1770 3) switch on floating point emulation in the kernel and pass
1771 the "no387" option to the kernel
1772 4) pass the "floppy=nodma" option to the kernel
1773 5) pass the "mem=4M" option to the kernel (thereby disabling
1774 all but the first 4 MB of RAM)
1775 6) make sure that the CPU is not over clocked.
1776 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1777 8) disable the cache from your BIOS settings
1778 9) install a fan for the video card or exchange video RAM
1779 10) install a better fan for the CPU
1780 11) exchange RAM chips
1781 12) exchange the motherboard.
1783 To compile this driver as a module, choose M here: the
1784 module will be called apm.
1786 if APM
1788 config APM_IGNORE_USER_SUSPEND
1789 bool "Ignore USER SUSPEND"
1790 ---help---
1791 This option will ignore USER SUSPEND requests. On machines with a
1792 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1793 series notebooks, it is necessary to say Y because of a BIOS bug.
1795 config APM_DO_ENABLE
1796 bool "Enable PM at boot time"
1797 ---help---
1798 Enable APM features at boot time. From page 36 of the APM BIOS
1799 specification: "When disabled, the APM BIOS does not automatically
1800 power manage devices, enter the Standby State, enter the Suspend
1801 State, or take power saving steps in response to CPU Idle calls."
1802 This driver will make CPU Idle calls when Linux is idle (unless this
1803 feature is turned off -- see "Do CPU IDLE calls", below). This
1804 should always save battery power, but more complicated APM features
1805 will be dependent on your BIOS implementation. You may need to turn
1806 this option off if your computer hangs at boot time when using APM
1807 support, or if it beeps continuously instead of suspending. Turn
1808 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1809 T400CDT. This is off by default since most machines do fine without
1810 this feature.
1812 config APM_CPU_IDLE
1813 bool "Make CPU Idle calls when idle"
1814 ---help---
1815 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1816 On some machines, this can activate improved power savings, such as
1817 a slowed CPU clock rate, when the machine is idle. These idle calls
1818 are made after the idle loop has run for some length of time (e.g.,
1819 333 mS). On some machines, this will cause a hang at boot time or
1820 whenever the CPU becomes idle. (On machines with more than one CPU,
1821 this option does nothing.)
1823 config APM_DISPLAY_BLANK
1824 bool "Enable console blanking using APM"
1825 ---help---
1826 Enable console blanking using the APM. Some laptops can use this to
1827 turn off the LCD backlight when the screen blanker of the Linux
1828 virtual console blanks the screen. Note that this is only used by
1829 the virtual console screen blanker, and won't turn off the backlight
1830 when using the X Window system. This also doesn't have anything to
1831 do with your VESA-compliant power-saving monitor. Further, this
1832 option doesn't work for all laptops -- it might not turn off your
1833 backlight at all, or it might print a lot of errors to the console,
1834 especially if you are using gpm.
1836 config APM_ALLOW_INTS
1837 bool "Allow interrupts during APM BIOS calls"
1838 ---help---
1839 Normally we disable external interrupts while we are making calls to
1840 the APM BIOS as a measure to lessen the effects of a badly behaving
1841 BIOS implementation. The BIOS should reenable interrupts if it
1842 needs to. Unfortunately, some BIOSes do not -- especially those in
1843 many of the newer IBM Thinkpads. If you experience hangs when you
1844 suspend, try setting this to Y. Otherwise, say N.
1846 endif # APM
1848 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1850 source "drivers/cpuidle/Kconfig"
1852 source "drivers/idle/Kconfig"
1854 endmenu
1857 menu "Bus options (PCI etc.)"
1859 config PCI
1860 bool "PCI support"
1861 default y
1862 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1863 ---help---
1864 Find out whether you have a PCI motherboard. PCI is the name of a
1865 bus system, i.e. the way the CPU talks to the other stuff inside
1866 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1867 VESA. If you have PCI, say Y, otherwise N.
1869 choice
1870 prompt "PCI access mode"
1871 depends on X86_32 && PCI
1872 default PCI_GOANY
1873 ---help---
1874 On PCI systems, the BIOS can be used to detect the PCI devices and
1875 determine their configuration. However, some old PCI motherboards
1876 have BIOS bugs and may crash if this is done. Also, some embedded
1877 PCI-based systems don't have any BIOS at all. Linux can also try to
1878 detect the PCI hardware directly without using the BIOS.
1880 With this option, you can specify how Linux should detect the
1881 PCI devices. If you choose "BIOS", the BIOS will be used,
1882 if you choose "Direct", the BIOS won't be used, and if you
1883 choose "MMConfig", then PCI Express MMCONFIG will be used.
1884 If you choose "Any", the kernel will try MMCONFIG, then the
1885 direct access method and falls back to the BIOS if that doesn't
1886 work. If unsure, go with the default, which is "Any".
1888 config PCI_GOBIOS
1889 bool "BIOS"
1891 config PCI_GOMMCONFIG
1892 bool "MMConfig"
1894 config PCI_GODIRECT
1895 bool "Direct"
1897 config PCI_GOOLPC
1898 bool "OLPC XO-1"
1899 depends on OLPC
1901 config PCI_GOANY
1902 bool "Any"
1904 endchoice
1906 config PCI_BIOS
1907 def_bool y
1908 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1910 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1911 config PCI_DIRECT
1912 def_bool y
1913 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1915 config PCI_MMCONFIG
1916 def_bool y
1917 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
1919 config PCI_OLPC
1920 def_bool y
1921 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1923 config PCI_XEN
1924 def_bool y
1925 depends on PCI && XEN
1926 select SWIOTLB_XEN
1928 config PCI_DOMAINS
1929 def_bool y
1930 depends on PCI
1932 config PCI_MMCONFIG
1933 bool "Support mmconfig PCI config space access"
1934 depends on X86_64 && PCI && ACPI
1936 config PCI_CNB20LE_QUIRK
1937 bool "Read CNB20LE Host Bridge Windows" if EMBEDDED
1938 default n
1939 depends on PCI && EXPERIMENTAL
1940 help
1941 Read the PCI windows out of the CNB20LE host bridge. This allows
1942 PCI hotplug to work on systems with the CNB20LE chipset which do
1943 not have ACPI.
1945 There's no public spec for this chipset, and this functionality
1946 is known to be incomplete.
1948 You should say N unless you know you need this.
1950 config DMAR
1951 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1952 depends on PCI_MSI && ACPI && EXPERIMENTAL
1953 help
1954 DMA remapping (DMAR) devices support enables independent address
1955 translations for Direct Memory Access (DMA) from devices.
1956 These DMA remapping devices are reported via ACPI tables
1957 and include PCI device scope covered by these DMA
1958 remapping devices.
1960 config DMAR_DEFAULT_ON
1961 def_bool y
1962 prompt "Enable DMA Remapping Devices by default"
1963 depends on DMAR
1964 help
1965 Selecting this option will enable a DMAR device at boot time if
1966 one is found. If this option is not selected, DMAR support can
1967 be enabled by passing intel_iommu=on to the kernel. It is
1968 recommended you say N here while the DMAR code remains
1969 experimental.
1971 config DMAR_BROKEN_GFX_WA
1972 bool "Workaround broken graphics drivers (going away soon)"
1973 depends on DMAR && BROKEN
1974 ---help---
1975 Current Graphics drivers tend to use physical address
1976 for DMA and avoid using DMA APIs. Setting this config
1977 option permits the IOMMU driver to set a unity map for
1978 all the OS-visible memory. Hence the driver can continue
1979 to use physical addresses for DMA, at least until this
1980 option is removed in the 2.6.32 kernel.
1982 config DMAR_FLOPPY_WA
1983 def_bool y
1984 depends on DMAR
1985 ---help---
1986 Floppy disk drivers are known to bypass DMA API calls
1987 thereby failing to work when IOMMU is enabled. This
1988 workaround will setup a 1:1 mapping for the first
1989 16MiB to make floppy (an ISA device) work.
1991 config INTR_REMAP
1992 bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1993 depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
1994 ---help---
1995 Supports Interrupt remapping for IO-APIC and MSI devices.
1996 To use x2apic mode in the CPU's which support x2APIC enhancements or
1997 to support platforms with CPU's having > 8 bit APIC ID, say Y.
1999 source "drivers/pci/pcie/Kconfig"
2001 source "drivers/pci/Kconfig"
2003 # x86_64 have no ISA slots, but do have ISA-style DMA.
2004 config ISA_DMA_API
2005 def_bool y
2007 if X86_32
2009 config ISA
2010 bool "ISA support"
2011 ---help---
2012 Find out whether you have ISA slots on your motherboard. ISA is the
2013 name of a bus system, i.e. the way the CPU talks to the other stuff
2014 inside your box. Other bus systems are PCI, EISA, MicroChannel
2015 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2016 newer boards don't support it. If you have ISA, say Y, otherwise N.
2018 config EISA
2019 bool "EISA support"
2020 depends on ISA
2021 ---help---
2022 The Extended Industry Standard Architecture (EISA) bus was
2023 developed as an open alternative to the IBM MicroChannel bus.
2025 The EISA bus provided some of the features of the IBM MicroChannel
2026 bus while maintaining backward compatibility with cards made for
2027 the older ISA bus. The EISA bus saw limited use between 1988 and
2028 1995 when it was made obsolete by the PCI bus.
2030 Say Y here if you are building a kernel for an EISA-based machine.
2032 Otherwise, say N.
2034 source "drivers/eisa/Kconfig"
2036 config MCA
2037 bool "MCA support"
2038 ---help---
2039 MicroChannel Architecture is found in some IBM PS/2 machines and
2040 laptops. It is a bus system similar to PCI or ISA. See
2041 <file:Documentation/mca.txt> (and especially the web page given
2042 there) before attempting to build an MCA bus kernel.
2044 source "drivers/mca/Kconfig"
2046 config SCx200
2047 tristate "NatSemi SCx200 support"
2048 ---help---
2049 This provides basic support for National Semiconductor's
2050 (now AMD's) Geode processors. The driver probes for the
2051 PCI-IDs of several on-chip devices, so its a good dependency
2052 for other scx200_* drivers.
2054 If compiled as a module, the driver is named scx200.
2056 config SCx200HR_TIMER
2057 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2058 depends on SCx200
2059 default y
2060 ---help---
2061 This driver provides a clocksource built upon the on-chip
2062 27MHz high-resolution timer. Its also a workaround for
2063 NSC Geode SC-1100's buggy TSC, which loses time when the
2064 processor goes idle (as is done by the scheduler). The
2065 other workaround is idle=poll boot option.
2067 config OLPC
2068 bool "One Laptop Per Child support"
2069 select GPIOLIB
2070 select OLPC_OPENFIRMWARE
2071 depends on !X86_64 && !X86_PAE
2072 ---help---
2073 Add support for detecting the unique features of the OLPC
2074 XO hardware.
2076 config OLPC_XO1
2077 tristate "OLPC XO-1 support"
2078 depends on OLPC && MFD_CS5535
2079 ---help---
2080 Add support for non-essential features of the OLPC XO-1 laptop.
2082 config OLPC_OPENFIRMWARE
2083 bool "Support for OLPC's Open Firmware"
2084 depends on !X86_64 && !X86_PAE
2085 default n
2086 select OF
2087 help
2088 This option adds support for the implementation of Open Firmware
2089 that is used on the OLPC XO-1 Children's Machine.
2090 If unsure, say N here.
2092 config OLPC_OPENFIRMWARE_DT
2093 bool
2094 default y if OLPC_OPENFIRMWARE && PROC_DEVICETREE
2095 select OF_PROMTREE
2097 endif # X86_32
2099 config AMD_NB
2100 def_bool y
2101 depends on CPU_SUP_AMD && PCI
2103 source "drivers/pcmcia/Kconfig"
2105 source "drivers/pci/hotplug/Kconfig"
2107 endmenu
2110 menu "Executable file formats / Emulations"
2112 source "fs/Kconfig.binfmt"
2114 config IA32_EMULATION
2115 bool "IA32 Emulation"
2116 depends on X86_64
2117 select COMPAT_BINFMT_ELF
2118 ---help---
2119 Include code to run 32-bit programs under a 64-bit kernel. You should
2120 likely turn this on, unless you're 100% sure that you don't have any
2121 32-bit programs left.
2123 config IA32_AOUT
2124 tristate "IA32 a.out support"
2125 depends on IA32_EMULATION
2126 ---help---
2127 Support old a.out binaries in the 32bit emulation.
2129 config COMPAT
2130 def_bool y
2131 depends on IA32_EMULATION
2133 config COMPAT_FOR_U64_ALIGNMENT
2134 def_bool COMPAT
2135 depends on X86_64
2137 config SYSVIPC_COMPAT
2138 def_bool y
2139 depends on COMPAT && SYSVIPC
2141 endmenu
2144 config HAVE_ATOMIC_IOMAP
2145 def_bool y
2146 depends on X86_32
2148 config HAVE_TEXT_POKE_SMP
2149 bool
2150 select STOP_MACHINE if SMP
2152 source "net/Kconfig"
2154 source "drivers/Kconfig"
2156 source "drivers/firmware/Kconfig"
2158 source "fs/Kconfig"
2160 source "arch/x86/Kconfig.debug"
2162 source "security/Kconfig"
2164 source "crypto/Kconfig"
2166 source "arch/x86/kvm/Kconfig"
2168 source "lib/Kconfig"