3 bool "64-bit kernel" if ARCH = "x86"
4 default ARCH = "x86_64"
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
15 select X86_DEV_DMA_OPS
20 select HAVE_AOUT if X86_32
21 select HAVE_UNSTABLE_SCHED_CLOCK
24 select HAVE_PCSPKR_PLATFORM
25 select HAVE_PERF_EVENTS
27 select HAVE_IOREMAP_PROT
30 select HAVE_MEMBLOCK_NODE_MAP
31 select ARCH_DISCARD_MEMBLOCK
32 select ARCH_WANT_OPTIONAL_GPIOLIB
33 select ARCH_WANT_FRAME_POINTERS
35 select HAVE_DMA_CONTIGUOUS if !SWIOTLB
36 select HAVE_KRETPROBES
38 select HAVE_FTRACE_MCOUNT_RECORD
39 select HAVE_C_RECORDMCOUNT
40 select HAVE_DYNAMIC_FTRACE
41 select HAVE_FUNCTION_TRACER
42 select HAVE_FUNCTION_GRAPH_TRACER
43 select HAVE_FUNCTION_GRAPH_FP_TEST
44 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
45 select HAVE_SYSCALL_TRACEPOINTS
48 select HAVE_ARCH_TRACEHOOK
49 select HAVE_GENERIC_DMA_COHERENT if X86_32
50 select HAVE_EFFICIENT_UNALIGNED_ACCESS
51 select USER_STACKTRACE_SUPPORT
52 select HAVE_REGS_AND_STACK_ACCESS_API
53 select HAVE_DMA_API_DEBUG
54 select HAVE_KERNEL_GZIP
55 select HAVE_KERNEL_BZIP2
56 select HAVE_KERNEL_LZMA
58 select HAVE_KERNEL_LZO
59 select HAVE_HW_BREAKPOINT
60 select HAVE_MIXED_BREAKPOINTS_REGS
62 select HAVE_PERF_EVENTS_NMI
64 select HAVE_ALIGNED_STRUCT_PAGE if SLUB && !M386
65 select HAVE_CMPXCHG_LOCAL if !M386
66 select HAVE_CMPXCHG_DOUBLE
67 select HAVE_ARCH_KMEMCHECK
68 select HAVE_USER_RETURN_NOTIFIER
69 select ARCH_BINFMT_ELF_RANDOMIZE_PIE
70 select HAVE_ARCH_JUMP_LABEL
71 select HAVE_TEXT_POKE_SMP
72 select HAVE_GENERIC_HARDIRQS
74 select GENERIC_FIND_FIRST_BIT
75 select GENERIC_IRQ_PROBE
76 select GENERIC_PENDING_IRQ if SMP
77 select GENERIC_IRQ_SHOW
78 select GENERIC_CLOCKEVENTS_MIN_ADJUST
79 select IRQ_FORCED_THREADING
80 select USE_GENERIC_SMP_HELPERS if SMP
81 select HAVE_BPF_JIT if X86_64
83 select ARCH_HAVE_NMI_SAFE_CMPXCHG
85 select DCACHE_WORD_ACCESS
86 select GENERIC_SMP_IDLE_THREAD
87 select HAVE_ARCH_SECCOMP_FILTER
88 select BUILDTIME_EXTABLE_SORT
89 select GENERIC_CMOS_UPDATE
90 select CLOCKSOURCE_WATCHDOG
91 select GENERIC_CLOCKEVENTS
92 select ARCH_CLOCKSOURCE_DATA if X86_64
93 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
94 select GENERIC_TIME_VSYSCALL if X86_64
95 select KTIME_SCALAR if X86_32
96 select GENERIC_STRNCPY_FROM_USER
97 select GENERIC_STRNLEN_USER
99 config INSTRUCTION_DECODER
100 def_bool (KPROBES || PERF_EVENTS || UPROBES)
104 default "elf32-i386" if X86_32
105 default "elf64-x86-64" if X86_64
107 config ARCH_DEFCONFIG
109 default "arch/x86/configs/i386_defconfig" if X86_32
110 default "arch/x86/configs/x86_64_defconfig" if X86_64
112 config LOCKDEP_SUPPORT
115 config STACKTRACE_SUPPORT
118 config HAVE_LATENCYTOP_SUPPORT
127 config NEED_DMA_MAP_STATE
128 def_bool (X86_64 || INTEL_IOMMU || DMA_API_DEBUG)
130 config NEED_SG_DMA_LENGTH
133 config GENERIC_ISA_DMA
139 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
141 config GENERIC_BUG_RELATIVE_POINTERS
144 config GENERIC_HWEIGHT
150 config ARCH_MAY_HAVE_PC_FDC
153 config RWSEM_GENERIC_SPINLOCK
156 config RWSEM_XCHGADD_ALGORITHM
159 config GENERIC_CALIBRATE_DELAY
162 config ARCH_HAS_CPU_RELAX
165 config ARCH_HAS_DEFAULT_IDLE
168 config ARCH_HAS_CACHE_LINE_SIZE
171 config ARCH_HAS_CPU_AUTOPROBE
174 config HAVE_SETUP_PER_CPU_AREA
177 config NEED_PER_CPU_EMBED_FIRST_CHUNK
180 config NEED_PER_CPU_PAGE_FIRST_CHUNK
183 config ARCH_HIBERNATION_POSSIBLE
186 config ARCH_SUSPEND_POSSIBLE
197 config ARCH_SUPPORTS_OPTIMIZED_INLINING
200 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
203 config HAVE_INTEL_TXT
205 depends on EXPERIMENTAL && INTEL_IOMMU && ACPI
209 depends on X86_32 && SMP
213 depends on X86_64 && SMP
219 config X86_32_LAZY_GS
221 depends on X86_32 && !CC_STACKPROTECTOR
223 config ARCH_HWEIGHT_CFLAGS
225 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
226 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
228 config ARCH_CPU_PROBE_RELEASE
230 depends on HOTPLUG_CPU
232 config ARCH_SUPPORTS_UPROBES
235 source "init/Kconfig"
236 source "kernel/Kconfig.freezer"
238 menu "Processor type and features"
241 bool "DMA memory allocation support" if EXPERT
244 DMA memory allocation support allows devices with less than 32-bit
245 addressing to allocate within the first 16MB of address space.
246 Disable if no such devices will be used.
251 bool "Symmetric multi-processing support"
253 This enables support for systems with more than one CPU. If you have
254 a system with only one CPU, like most personal computers, say N. If
255 you have a system with more than one CPU, say Y.
257 If you say N here, the kernel will run on single and multiprocessor
258 machines, but will use only one CPU of a multiprocessor machine. If
259 you say Y here, the kernel will run on many, but not all,
260 singleprocessor machines. On a singleprocessor machine, the kernel
261 will run faster if you say N here.
263 Note that if you say Y here and choose architecture "586" or
264 "Pentium" under "Processor family", the kernel will not work on 486
265 architectures. Similarly, multiprocessor kernels for the "PPro"
266 architecture may not work on all Pentium based boards.
268 People using multiprocessor machines who say Y here should also say
269 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
270 Management" code will be disabled if you say Y here.
272 See also <file:Documentation/x86/i386/IO-APIC.txt>,
273 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
274 <http://www.tldp.org/docs.html#howto>.
276 If you don't know what to do here, say N.
279 bool "Support x2apic"
280 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
282 This enables x2apic support on CPUs that have this feature.
284 This allows 32-bit apic IDs (so it can support very large systems),
285 and accesses the local apic via MSRs not via mmio.
287 If you don't know what to do here, say N.
290 bool "Enable MPS table" if ACPI
292 depends on X86_LOCAL_APIC
294 For old smp systems that do not have proper acpi support. Newer systems
295 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
298 bool "Support for big SMP systems with more than 8 CPUs"
299 depends on X86_32 && SMP
301 This option is needed for the systems that have more than 8 CPUs
304 config X86_EXTENDED_PLATFORM
305 bool "Support for extended (non-PC) x86 platforms"
308 If you disable this option then the kernel will only support
309 standard PC platforms. (which covers the vast majority of
312 If you enable this option then you'll be able to select support
313 for the following (non-PC) 32 bit x86 platforms:
317 SGI 320/540 (Visual Workstation)
318 STA2X11-based (e.g. Northville)
319 Summit/EXA (IBM x440)
320 Unisys ES7000 IA32 series
321 Moorestown MID devices
323 If you have one of these systems, or if you want to build a
324 generic distribution kernel, say Y here - otherwise say N.
328 config X86_EXTENDED_PLATFORM
329 bool "Support for extended (non-PC) x86 platforms"
332 If you disable this option then the kernel will only support
333 standard PC platforms. (which covers the vast majority of
336 If you enable this option then you'll be able to select support
337 for the following (non-PC) 64 bit x86 platforms:
342 If you have one of these systems, or if you want to build a
343 generic distribution kernel, say Y here - otherwise say N.
345 # This is an alphabetically sorted list of 64 bit extended platforms
346 # Please maintain the alphabetic order if and when there are additions
348 bool "Numascale NumaChip"
350 depends on X86_EXTENDED_PLATFORM
353 depends on X86_X2APIC
355 Adds support for Numascale NumaChip large-SMP systems. Needed to
356 enable more than ~168 cores.
357 If you don't have one of these, you should say N here.
361 select PARAVIRT_GUEST
363 depends on X86_64 && PCI
364 depends on X86_EXTENDED_PLATFORM
367 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
368 supposed to run on these EM64T-based machines. Only choose this option
369 if you have one of these machines.
372 bool "SGI Ultraviolet"
374 depends on X86_EXTENDED_PLATFORM
376 depends on X86_X2APIC
378 This option is needed in order to support SGI Ultraviolet systems.
379 If you don't have one of these, you should say N here.
381 # Following is an alphabetically sorted list of 32 bit extended platforms
382 # Please maintain the alphabetic order if and when there are additions
385 bool "CE4100 TV platform"
387 depends on PCI_GODIRECT
389 depends on X86_EXTENDED_PLATFORM
390 select X86_REBOOTFIXUPS
392 select OF_EARLY_FLATTREE
395 Select for the Intel CE media processor (CE4100) SOC.
396 This option compiles in support for the CE4100 SOC for settop
397 boxes and media devices.
399 config X86_WANT_INTEL_MID
400 bool "Intel MID platform support"
402 depends on X86_EXTENDED_PLATFORM
404 Select to build a kernel capable of supporting Intel MID platform
405 systems which do not have the PCI legacy interfaces (Moorestown,
406 Medfield). If you are building for a PC class system say N here.
408 if X86_WANT_INTEL_MID
414 bool "Medfield MID platform"
417 depends on X86_IO_APIC
425 select X86_PLATFORM_DEVICES
426 select MFD_INTEL_MSIC
428 Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin
429 Internet Device(MID) platform.
430 Unlike standard x86 PCs, Medfield does not have many legacy devices
431 nor standard legacy replacement devices/features. e.g. Medfield does
432 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
437 bool "RDC R-321x SoC"
439 depends on X86_EXTENDED_PLATFORM
441 select X86_REBOOTFIXUPS
443 This option is needed for RDC R-321x system-on-chip, also known
445 If you don't have one of these chips, you should say N here.
447 config X86_32_NON_STANDARD
448 bool "Support non-standard 32-bit SMP architectures"
449 depends on X86_32 && SMP
450 depends on X86_EXTENDED_PLATFORM
452 This option compiles in the NUMAQ, Summit, bigsmp, ES7000,
453 STA2X11, default subarchitectures. It is intended for a generic
454 binary kernel. If you select them all, kernel will probe it
455 one by one and will fallback to default.
457 # Alphabetically sorted list of Non standard 32 bit platforms
460 bool "NUMAQ (IBM/Sequent)"
461 depends on X86_32_NON_STANDARD
466 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
467 NUMA multiquad box. This changes the way that processors are
468 bootstrapped, and uses Clustered Logical APIC addressing mode instead
469 of Flat Logical. You will need a new lynxer.elf file to flash your
470 firmware with - send email to <Martin.Bligh@us.ibm.com>.
472 config X86_SUPPORTS_MEMORY_FAILURE
474 # MCE code calls memory_failure():
476 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
477 depends on !X86_NUMAQ
478 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
479 depends on X86_64 || !SPARSEMEM
480 select ARCH_SUPPORTS_MEMORY_FAILURE
483 bool "SGI 320/540 (Visual Workstation)"
484 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
485 depends on X86_32_NON_STANDARD
487 The SGI Visual Workstation series is an IA32-based workstation
488 based on SGI systems chips with some legacy PC hardware attached.
490 Say Y here to create a kernel to run on the SGI 320 or 540.
492 A kernel compiled for the Visual Workstation will run on general
493 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
496 bool "STA2X11 Companion Chip Support"
497 depends on X86_32_NON_STANDARD && PCI
498 select X86_DEV_DMA_OPS
502 select ARCH_REQUIRE_GPIOLIB
505 This adds support for boards based on the STA2X11 IO-Hub,
506 a.k.a. "ConneXt". The chip is used in place of the standard
507 PC chipset, so all "standard" peripherals are missing. If this
508 option is selected the kernel will still be able to boot on
509 standard PC machines.
512 bool "Summit/EXA (IBM x440)"
513 depends on X86_32_NON_STANDARD
515 This option is needed for IBM systems that use the Summit/EXA chipset.
516 In particular, it is needed for the x440.
519 bool "Unisys ES7000 IA32 series"
520 depends on X86_32_NON_STANDARD && X86_BIGSMP
522 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
523 supposed to run on an IA32-based Unisys ES7000 system.
526 tristate "Eurobraille/Iris poweroff module"
529 The Iris machines from EuroBraille do not have APM or ACPI support
530 to shut themselves down properly. A special I/O sequence is
531 needed to do so, which is what this module does at
534 This is only for Iris machines from EuroBraille.
538 config SCHED_OMIT_FRAME_POINTER
540 prompt "Single-depth WCHAN output"
543 Calculate simpler /proc/<PID>/wchan values. If this option
544 is disabled then wchan values will recurse back to the
545 caller function. This provides more accurate wchan values,
546 at the expense of slightly more scheduling overhead.
548 If in doubt, say "Y".
550 menuconfig PARAVIRT_GUEST
551 bool "Paravirtualized guest support"
553 Say Y here to get to see options related to running Linux under
554 various hypervisors. This option alone does not add any kernel code.
556 If you say N, all options in this submenu will be skipped and disabled.
560 config PARAVIRT_TIME_ACCOUNTING
561 bool "Paravirtual steal time accounting"
565 Select this option to enable fine granularity task steal time
566 accounting. Time spent executing other tasks in parallel with
567 the current vCPU is discounted from the vCPU power. To account for
568 that, there can be a small performance impact.
570 If in doubt, say N here.
572 source "arch/x86/xen/Kconfig"
575 bool "KVM paravirtualized clock"
577 select PARAVIRT_CLOCK
579 Turning on this option will allow you to run a paravirtualized clock
580 when running over the KVM hypervisor. Instead of relying on a PIT
581 (or probably other) emulation by the underlying device model, the host
582 provides the guest with timing infrastructure such as time of day, and
586 bool "KVM Guest support"
589 This option enables various optimizations for running under the KVM
592 source "arch/x86/lguest/Kconfig"
595 bool "Enable paravirtualization code"
597 This changes the kernel so it can modify itself when it is run
598 under a hypervisor, potentially improving performance significantly
599 over full virtualization. However, when run without a hypervisor
600 the kernel is theoretically slower and slightly larger.
602 config PARAVIRT_SPINLOCKS
603 bool "Paravirtualization layer for spinlocks"
604 depends on PARAVIRT && SMP && EXPERIMENTAL
606 Paravirtualized spinlocks allow a pvops backend to replace the
607 spinlock implementation with something virtualization-friendly
608 (for example, block the virtual CPU rather than spinning).
610 Unfortunately the downside is an up to 5% performance hit on
611 native kernels, with various workloads.
613 If you are unsure how to answer this question, answer N.
615 config PARAVIRT_CLOCK
620 config PARAVIRT_DEBUG
621 bool "paravirt-ops debugging"
622 depends on PARAVIRT && DEBUG_KERNEL
624 Enable to debug paravirt_ops internals. Specifically, BUG if
625 a paravirt_op is missing when it is called.
633 This option adds a kernel parameter 'memtest', which allows memtest
635 memtest=0, mean disabled; -- default
636 memtest=1, mean do 1 test pattern;
638 memtest=4, mean do 4 test patterns.
639 If you are unsure how to answer this question, answer N.
641 config X86_SUMMIT_NUMA
643 depends on X86_32 && NUMA && X86_32_NON_STANDARD
645 config X86_CYCLONE_TIMER
647 depends on X86_SUMMIT
649 source "arch/x86/Kconfig.cpu"
653 prompt "HPET Timer Support" if X86_32
655 Use the IA-PC HPET (High Precision Event Timer) to manage
656 time in preference to the PIT and RTC, if a HPET is
658 HPET is the next generation timer replacing legacy 8254s.
659 The HPET provides a stable time base on SMP
660 systems, unlike the TSC, but it is more expensive to access,
661 as it is off-chip. You can find the HPET spec at
662 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
664 You can safely choose Y here. However, HPET will only be
665 activated if the platform and the BIOS support this feature.
666 Otherwise the 8254 will be used for timing services.
668 Choose N to continue using the legacy 8254 timer.
670 config HPET_EMULATE_RTC
672 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
675 def_bool y if X86_INTEL_MID
676 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
678 depends on X86_INTEL_MID && SFI
680 APB timer is the replacement for 8254, HPET on X86 MID platforms.
681 The APBT provides a stable time base on SMP
682 systems, unlike the TSC, but it is more expensive to access,
683 as it is off-chip. APB timers are always running regardless of CPU
684 C states, they are used as per CPU clockevent device when possible.
686 # Mark as expert because too many people got it wrong.
687 # The code disables itself when not needed.
690 bool "Enable DMI scanning" if EXPERT
692 Enabled scanning of DMI to identify machine quirks. Say Y
693 here unless you have verified that your setup is not
694 affected by entries in the DMI blacklist. Required by PNP
698 bool "GART IOMMU support" if EXPERT
701 depends on X86_64 && PCI && AMD_NB
703 Support for full DMA access of devices with 32bit memory access only
704 on systems with more than 3GB. This is usually needed for USB,
705 sound, many IDE/SATA chipsets and some other devices.
706 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
707 based hardware IOMMU and a software bounce buffer based IOMMU used
708 on Intel systems and as fallback.
709 The code is only active when needed (enough memory and limited
710 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
714 bool "IBM Calgary IOMMU support"
716 depends on X86_64 && PCI && EXPERIMENTAL
718 Support for hardware IOMMUs in IBM's xSeries x366 and x460
719 systems. Needed to run systems with more than 3GB of memory
720 properly with 32-bit PCI devices that do not support DAC
721 (Double Address Cycle). Calgary also supports bus level
722 isolation, where all DMAs pass through the IOMMU. This
723 prevents them from going anywhere except their intended
724 destination. This catches hard-to-find kernel bugs and
725 mis-behaving drivers and devices that do not use the DMA-API
726 properly to set up their DMA buffers. The IOMMU can be
727 turned off at boot time with the iommu=off parameter.
728 Normally the kernel will make the right choice by itself.
731 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
733 prompt "Should Calgary be enabled by default?"
734 depends on CALGARY_IOMMU
736 Should Calgary be enabled by default? if you choose 'y', Calgary
737 will be used (if it exists). If you choose 'n', Calgary will not be
738 used even if it exists. If you choose 'n' and would like to use
739 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
742 # need this always selected by IOMMU for the VIA workaround
746 Support for software bounce buffers used on x86-64 systems
747 which don't have a hardware IOMMU (e.g. the current generation
748 of Intel's x86-64 CPUs). Using this PCI devices which can only
749 access 32-bits of memory can be used on systems with more than
750 3 GB of memory. If unsure, say Y.
753 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
756 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
757 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
758 select CPUMASK_OFFSTACK
760 Enable maximum number of CPUS and NUMA Nodes for this architecture.
764 int "Maximum number of CPUs" if SMP && !MAXSMP
765 range 2 8 if SMP && X86_32 && !X86_BIGSMP
766 range 2 512 if SMP && !MAXSMP
768 default "4096" if MAXSMP
769 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
772 This allows you to specify the maximum number of CPUs which this
773 kernel will support. The maximum supported value is 512 and the
774 minimum value which makes sense is 2.
776 This is purely to save memory - each supported CPU adds
777 approximately eight kilobytes to the kernel image.
780 bool "SMT (Hyperthreading) scheduler support"
783 SMT scheduler support improves the CPU scheduler's decision making
784 when dealing with Intel Pentium 4 chips with HyperThreading at a
785 cost of slightly increased overhead in some places. If unsure say
790 prompt "Multi-core scheduler support"
793 Multi-core scheduler support improves the CPU scheduler's decision
794 making when dealing with multi-core CPU chips at a cost of slightly
795 increased overhead in some places. If unsure say N here.
797 config IRQ_TIME_ACCOUNTING
798 bool "Fine granularity task level IRQ time accounting"
801 Select this option to enable fine granularity task irq time
802 accounting. This is done by reading a timestamp on each
803 transitions between softirq and hardirq state, so there can be a
804 small performance impact.
806 If in doubt, say N here.
808 source "kernel/Kconfig.preempt"
811 bool "Local APIC support on uniprocessors"
812 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
814 A local APIC (Advanced Programmable Interrupt Controller) is an
815 integrated interrupt controller in the CPU. If you have a single-CPU
816 system which has a processor with a local APIC, you can say Y here to
817 enable and use it. If you say Y here even though your machine doesn't
818 have a local APIC, then the kernel will still run with no slowdown at
819 all. The local APIC supports CPU-generated self-interrupts (timer,
820 performance counters), and the NMI watchdog which detects hard
824 bool "IO-APIC support on uniprocessors"
825 depends on X86_UP_APIC
827 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
828 SMP-capable replacement for PC-style interrupt controllers. Most
829 SMP systems and many recent uniprocessor systems have one.
831 If you have a single-CPU system with an IO-APIC, you can say Y here
832 to use it. If you say Y here even though your machine doesn't have
833 an IO-APIC, then the kernel will still run with no slowdown at all.
835 config X86_LOCAL_APIC
837 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
841 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC
843 config X86_VISWS_APIC
845 depends on X86_32 && X86_VISWS
847 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
848 bool "Reroute for broken boot IRQs"
849 depends on X86_IO_APIC
851 This option enables a workaround that fixes a source of
852 spurious interrupts. This is recommended when threaded
853 interrupt handling is used on systems where the generation of
854 superfluous "boot interrupts" cannot be disabled.
856 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
857 entry in the chipset's IO-APIC is masked (as, e.g. the RT
858 kernel does during interrupt handling). On chipsets where this
859 boot IRQ generation cannot be disabled, this workaround keeps
860 the original IRQ line masked so that only the equivalent "boot
861 IRQ" is delivered to the CPUs. The workaround also tells the
862 kernel to set up the IRQ handler on the boot IRQ line. In this
863 way only one interrupt is delivered to the kernel. Otherwise
864 the spurious second interrupt may cause the kernel to bring
865 down (vital) interrupt lines.
867 Only affects "broken" chipsets. Interrupt sharing may be
868 increased on these systems.
871 bool "Machine Check / overheating reporting"
873 Machine Check support allows the processor to notify the
874 kernel if it detects a problem (e.g. overheating, data corruption).
875 The action the kernel takes depends on the severity of the problem,
876 ranging from warning messages to halting the machine.
880 prompt "Intel MCE features"
881 depends on X86_MCE && X86_LOCAL_APIC
883 Additional support for intel specific MCE features such as
888 prompt "AMD MCE features"
889 depends on X86_MCE && X86_LOCAL_APIC
891 Additional support for AMD specific MCE features such as
892 the DRAM Error Threshold.
894 config X86_ANCIENT_MCE
895 bool "Support for old Pentium 5 / WinChip machine checks"
896 depends on X86_32 && X86_MCE
898 Include support for machine check handling on old Pentium 5 or WinChip
899 systems. These typically need to be enabled explicitely on the command
902 config X86_MCE_THRESHOLD
903 depends on X86_MCE_AMD || X86_MCE_INTEL
906 config X86_MCE_INJECT
908 tristate "Machine check injector support"
910 Provide support for injecting machine checks for testing purposes.
911 If you don't know what a machine check is and you don't do kernel
912 QA it is safe to say n.
914 config X86_THERMAL_VECTOR
916 depends on X86_MCE_INTEL
919 bool "Enable VM86 support" if EXPERT
923 This option is required by programs like DOSEMU to run 16-bit legacy
924 code on X86 processors. It also may be needed by software like
925 XFree86 to initialize some video cards via BIOS. Disabling this
926 option saves about 6k.
929 tristate "Toshiba Laptop support"
932 This adds a driver to safely access the System Management Mode of
933 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
934 not work on models with a Phoenix BIOS. The System Management Mode
935 is used to set the BIOS and power saving options on Toshiba portables.
937 For information on utilities to make use of this driver see the
938 Toshiba Linux utilities web site at:
939 <http://www.buzzard.org.uk/toshiba/>.
941 Say Y if you intend to run this kernel on a Toshiba portable.
945 tristate "Dell laptop support"
948 This adds a driver to safely access the System Management Mode
949 of the CPU on the Dell Inspiron 8000. The System Management Mode
950 is used to read cpu temperature and cooling fan status and to
951 control the fans on the I8K portables.
953 This driver has been tested only on the Inspiron 8000 but it may
954 also work with other Dell laptops. You can force loading on other
955 models by passing the parameter `force=1' to the module. Use at
958 For information on utilities to make use of this driver see the
959 I8K Linux utilities web site at:
960 <http://people.debian.org/~dz/i8k/>
962 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
965 config X86_REBOOTFIXUPS
966 bool "Enable X86 board specific fixups for reboot"
969 This enables chipset and/or board specific fixups to be done
970 in order to get reboot to work correctly. This is only needed on
971 some combinations of hardware and BIOS. The symptom, for which
972 this config is intended, is when reboot ends with a stalled/hung
975 Currently, the only fixup is for the Geode machines using
976 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
978 Say Y if you want to enable the fixup. Currently, it's safe to
979 enable this option even if you don't need it.
983 tristate "/dev/cpu/microcode - microcode support"
986 If you say Y here, you will be able to update the microcode on
987 certain Intel and AMD processors. The Intel support is for the
988 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
989 Pentium 4, Xeon etc. The AMD support is for family 0x10 and
990 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
991 You will obviously need the actual microcode binary data itself
992 which is not shipped with the Linux kernel.
994 This option selects the general module only, you need to select
995 at least one vendor specific module as well.
997 To compile this driver as a module, choose M here: the
998 module will be called microcode.
1000 config MICROCODE_INTEL
1001 bool "Intel microcode patch loading support"
1002 depends on MICROCODE
1006 This options enables microcode patch loading support for Intel
1009 For latest news and information on obtaining all the required
1010 Intel ingredients for this driver, check:
1011 <http://www.urbanmyth.org/microcode/>.
1013 config MICROCODE_AMD
1014 bool "AMD microcode patch loading support"
1015 depends on MICROCODE
1018 If you select this option, microcode patch loading support for AMD
1019 processors will be enabled.
1021 config MICROCODE_OLD_INTERFACE
1023 depends on MICROCODE
1026 tristate "/dev/cpu/*/msr - Model-specific register support"
1028 This device gives privileged processes access to the x86
1029 Model-Specific Registers (MSRs). It is a character device with
1030 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1031 MSR accesses are directed to a specific CPU on multi-processor
1035 tristate "/dev/cpu/*/cpuid - CPU information support"
1037 This device gives processes access to the x86 CPUID instruction to
1038 be executed on a specific processor. It is a character device
1039 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1043 prompt "High Memory Support"
1044 default HIGHMEM64G if X86_NUMAQ
1050 depends on !X86_NUMAQ
1052 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1053 However, the address space of 32-bit x86 processors is only 4
1054 Gigabytes large. That means that, if you have a large amount of
1055 physical memory, not all of it can be "permanently mapped" by the
1056 kernel. The physical memory that's not permanently mapped is called
1059 If you are compiling a kernel which will never run on a machine with
1060 more than 1 Gigabyte total physical RAM, answer "off" here (default
1061 choice and suitable for most users). This will result in a "3GB/1GB"
1062 split: 3GB are mapped so that each process sees a 3GB virtual memory
1063 space and the remaining part of the 4GB virtual memory space is used
1064 by the kernel to permanently map as much physical memory as
1067 If the machine has between 1 and 4 Gigabytes physical RAM, then
1070 If more than 4 Gigabytes is used then answer "64GB" here. This
1071 selection turns Intel PAE (Physical Address Extension) mode on.
1072 PAE implements 3-level paging on IA32 processors. PAE is fully
1073 supported by Linux, PAE mode is implemented on all recent Intel
1074 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1075 then the kernel will not boot on CPUs that don't support PAE!
1077 The actual amount of total physical memory will either be
1078 auto detected or can be forced by using a kernel command line option
1079 such as "mem=256M". (Try "man bootparam" or see the documentation of
1080 your boot loader (lilo or loadlin) about how to pass options to the
1081 kernel at boot time.)
1083 If unsure, say "off".
1087 depends on !X86_NUMAQ
1089 Select this if you have a 32-bit processor and between 1 and 4
1090 gigabytes of physical RAM.
1094 depends on !M386 && !M486
1097 Select this if you have a 32-bit processor and more than 4
1098 gigabytes of physical RAM.
1103 depends on EXPERIMENTAL
1104 prompt "Memory split" if EXPERT
1108 Select the desired split between kernel and user memory.
1110 If the address range available to the kernel is less than the
1111 physical memory installed, the remaining memory will be available
1112 as "high memory". Accessing high memory is a little more costly
1113 than low memory, as it needs to be mapped into the kernel first.
1114 Note that increasing the kernel address space limits the range
1115 available to user programs, making the address space there
1116 tighter. Selecting anything other than the default 3G/1G split
1117 will also likely make your kernel incompatible with binary-only
1120 If you are not absolutely sure what you are doing, leave this
1124 bool "3G/1G user/kernel split"
1125 config VMSPLIT_3G_OPT
1127 bool "3G/1G user/kernel split (for full 1G low memory)"
1129 bool "2G/2G user/kernel split"
1130 config VMSPLIT_2G_OPT
1132 bool "2G/2G user/kernel split (for full 2G low memory)"
1134 bool "1G/3G user/kernel split"
1139 default 0xB0000000 if VMSPLIT_3G_OPT
1140 default 0x80000000 if VMSPLIT_2G
1141 default 0x78000000 if VMSPLIT_2G_OPT
1142 default 0x40000000 if VMSPLIT_1G
1148 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1151 bool "PAE (Physical Address Extension) Support"
1152 depends on X86_32 && !HIGHMEM4G
1154 PAE is required for NX support, and furthermore enables
1155 larger swapspace support for non-overcommit purposes. It
1156 has the cost of more pagetable lookup overhead, and also
1157 consumes more pagetable space per process.
1159 config ARCH_PHYS_ADDR_T_64BIT
1160 def_bool X86_64 || X86_PAE
1162 config ARCH_DMA_ADDR_T_64BIT
1163 def_bool X86_64 || HIGHMEM64G
1165 config DIRECT_GBPAGES
1166 bool "Enable 1GB pages for kernel pagetables" if EXPERT
1170 Allow the kernel linear mapping to use 1GB pages on CPUs that
1171 support it. This can improve the kernel's performance a tiny bit by
1172 reducing TLB pressure. If in doubt, say "Y".
1174 # Common NUMA Features
1176 bool "Numa Memory Allocation and Scheduler Support"
1178 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1179 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1181 Enable NUMA (Non Uniform Memory Access) support.
1183 The kernel will try to allocate memory used by a CPU on the
1184 local memory controller of the CPU and add some more
1185 NUMA awareness to the kernel.
1187 For 64-bit this is recommended if the system is Intel Core i7
1188 (or later), AMD Opteron, or EM64T NUMA.
1190 For 32-bit this is only needed on (rare) 32-bit-only platforms
1191 that support NUMA topologies, such as NUMAQ / Summit, or if you
1192 boot a 32-bit kernel on a 64-bit NUMA platform.
1194 Otherwise, you should say N.
1196 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1197 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1201 prompt "Old style AMD Opteron NUMA detection"
1202 depends on X86_64 && NUMA && PCI
1204 Enable AMD NUMA node topology detection. You should say Y here if
1205 you have a multi processor AMD system. This uses an old method to
1206 read the NUMA configuration directly from the builtin Northbridge
1207 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1208 which also takes priority if both are compiled in.
1210 config X86_64_ACPI_NUMA
1212 prompt "ACPI NUMA detection"
1213 depends on X86_64 && NUMA && ACPI && PCI
1216 Enable ACPI SRAT based node topology detection.
1218 # Some NUMA nodes have memory ranges that span
1219 # other nodes. Even though a pfn is valid and
1220 # between a node's start and end pfns, it may not
1221 # reside on that node. See memmap_init_zone()
1223 config NODES_SPAN_OTHER_NODES
1225 depends on X86_64_ACPI_NUMA
1228 bool "NUMA emulation"
1231 Enable NUMA emulation. A flat machine will be split
1232 into virtual nodes when booted with "numa=fake=N", where N is the
1233 number of nodes. This is only useful for debugging.
1236 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1238 default "10" if MAXSMP
1239 default "6" if X86_64
1240 default "4" if X86_NUMAQ
1242 depends on NEED_MULTIPLE_NODES
1244 Specify the maximum number of NUMA Nodes available on the target
1245 system. Increases memory reserved to accommodate various tables.
1247 config HAVE_ARCH_ALLOC_REMAP
1249 depends on X86_32 && NUMA
1251 config ARCH_HAVE_MEMORY_PRESENT
1253 depends on X86_32 && DISCONTIGMEM
1255 config NEED_NODE_MEMMAP_SIZE
1257 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1259 config ARCH_FLATMEM_ENABLE
1261 depends on X86_32 && !NUMA
1263 config ARCH_DISCONTIGMEM_ENABLE
1265 depends on NUMA && X86_32
1267 config ARCH_DISCONTIGMEM_DEFAULT
1269 depends on NUMA && X86_32
1271 config ARCH_SPARSEMEM_ENABLE
1273 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1274 select SPARSEMEM_STATIC if X86_32
1275 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1277 config ARCH_SPARSEMEM_DEFAULT
1281 config ARCH_SELECT_MEMORY_MODEL
1283 depends on ARCH_SPARSEMEM_ENABLE
1285 config ARCH_MEMORY_PROBE
1287 depends on MEMORY_HOTPLUG
1289 config ARCH_PROC_KCORE_TEXT
1291 depends on X86_64 && PROC_KCORE
1293 config ILLEGAL_POINTER_VALUE
1296 default 0xdead000000000000 if X86_64
1301 bool "Allocate 3rd-level pagetables from highmem"
1304 The VM uses one page table entry for each page of physical memory.
1305 For systems with a lot of RAM, this can be wasteful of precious
1306 low memory. Setting this option will put user-space page table
1307 entries in high memory.
1309 config X86_CHECK_BIOS_CORRUPTION
1310 bool "Check for low memory corruption"
1312 Periodically check for memory corruption in low memory, which
1313 is suspected to be caused by BIOS. Even when enabled in the
1314 configuration, it is disabled at runtime. Enable it by
1315 setting "memory_corruption_check=1" on the kernel command
1316 line. By default it scans the low 64k of memory every 60
1317 seconds; see the memory_corruption_check_size and
1318 memory_corruption_check_period parameters in
1319 Documentation/kernel-parameters.txt to adjust this.
1321 When enabled with the default parameters, this option has
1322 almost no overhead, as it reserves a relatively small amount
1323 of memory and scans it infrequently. It both detects corruption
1324 and prevents it from affecting the running system.
1326 It is, however, intended as a diagnostic tool; if repeatable
1327 BIOS-originated corruption always affects the same memory,
1328 you can use memmap= to prevent the kernel from using that
1331 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1332 bool "Set the default setting of memory_corruption_check"
1333 depends on X86_CHECK_BIOS_CORRUPTION
1336 Set whether the default state of memory_corruption_check is
1339 config X86_RESERVE_LOW
1340 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1344 Specify the amount of low memory to reserve for the BIOS.
1346 The first page contains BIOS data structures that the kernel
1347 must not use, so that page must always be reserved.
1349 By default we reserve the first 64K of physical RAM, as a
1350 number of BIOSes are known to corrupt that memory range
1351 during events such as suspend/resume or monitor cable
1352 insertion, so it must not be used by the kernel.
1354 You can set this to 4 if you are absolutely sure that you
1355 trust the BIOS to get all its memory reservations and usages
1356 right. If you know your BIOS have problems beyond the
1357 default 64K area, you can set this to 640 to avoid using the
1358 entire low memory range.
1360 If you have doubts about the BIOS (e.g. suspend/resume does
1361 not work or there's kernel crashes after certain hardware
1362 hotplug events) then you might want to enable
1363 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1364 typical corruption patterns.
1366 Leave this to the default value of 64 if you are unsure.
1368 config MATH_EMULATION
1370 prompt "Math emulation" if X86_32
1372 Linux can emulate a math coprocessor (used for floating point
1373 operations) if you don't have one. 486DX and Pentium processors have
1374 a math coprocessor built in, 486SX and 386 do not, unless you added
1375 a 487DX or 387, respectively. (The messages during boot time can
1376 give you some hints here ["man dmesg"].) Everyone needs either a
1377 coprocessor or this emulation.
1379 If you don't have a math coprocessor, you need to say Y here; if you
1380 say Y here even though you have a coprocessor, the coprocessor will
1381 be used nevertheless. (This behavior can be changed with the kernel
1382 command line option "no387", which comes handy if your coprocessor
1383 is broken. Try "man bootparam" or see the documentation of your boot
1384 loader (lilo or loadlin) about how to pass options to the kernel at
1385 boot time.) This means that it is a good idea to say Y here if you
1386 intend to use this kernel on different machines.
1388 More information about the internals of the Linux math coprocessor
1389 emulation can be found in <file:arch/x86/math-emu/README>.
1391 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1392 kernel, it won't hurt.
1396 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1398 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1399 the Memory Type Range Registers (MTRRs) may be used to control
1400 processor access to memory ranges. This is most useful if you have
1401 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1402 allows bus write transfers to be combined into a larger transfer
1403 before bursting over the PCI/AGP bus. This can increase performance
1404 of image write operations 2.5 times or more. Saying Y here creates a
1405 /proc/mtrr file which may be used to manipulate your processor's
1406 MTRRs. Typically the X server should use this.
1408 This code has a reasonably generic interface so that similar
1409 control registers on other processors can be easily supported
1412 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1413 Registers (ARRs) which provide a similar functionality to MTRRs. For
1414 these, the ARRs are used to emulate the MTRRs.
1415 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1416 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1417 write-combining. All of these processors are supported by this code
1418 and it makes sense to say Y here if you have one of them.
1420 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1421 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1422 can lead to all sorts of problems, so it's good to say Y here.
1424 You can safely say Y even if your machine doesn't have MTRRs, you'll
1425 just add about 9 KB to your kernel.
1427 See <file:Documentation/x86/mtrr.txt> for more information.
1429 config MTRR_SANITIZER
1431 prompt "MTRR cleanup support"
1434 Convert MTRR layout from continuous to discrete, so X drivers can
1435 add writeback entries.
1437 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1438 The largest mtrr entry size for a continuous block can be set with
1443 config MTRR_SANITIZER_ENABLE_DEFAULT
1444 int "MTRR cleanup enable value (0-1)"
1447 depends on MTRR_SANITIZER
1449 Enable mtrr cleanup default value
1451 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1452 int "MTRR cleanup spare reg num (0-7)"
1455 depends on MTRR_SANITIZER
1457 mtrr cleanup spare entries default, it can be changed via
1458 mtrr_spare_reg_nr=N on the kernel command line.
1462 prompt "x86 PAT support" if EXPERT
1465 Use PAT attributes to setup page level cache control.
1467 PATs are the modern equivalents of MTRRs and are much more
1468 flexible than MTRRs.
1470 Say N here if you see bootup problems (boot crash, boot hang,
1471 spontaneous reboots) or a non-working video driver.
1475 config ARCH_USES_PG_UNCACHED
1481 prompt "x86 architectural random number generator" if EXPERT
1483 Enable the x86 architectural RDRAND instruction
1484 (Intel Bull Mountain technology) to generate random numbers.
1485 If supported, this is a high bandwidth, cryptographically
1486 secure hardware random number generator.
1489 bool "EFI runtime service support"
1492 This enables the kernel to use EFI runtime services that are
1493 available (such as the EFI variable services).
1495 This option is only useful on systems that have EFI firmware.
1496 In addition, you should use the latest ELILO loader available
1497 at <http://elilo.sourceforge.net> in order to take advantage
1498 of EFI runtime services. However, even with this option, the
1499 resultant kernel should continue to boot on existing non-EFI
1503 bool "EFI stub support"
1506 This kernel feature allows a bzImage to be loaded directly
1507 by EFI firmware without the use of a bootloader.
1509 See Documentation/x86/efi-stub.txt for more information.
1513 prompt "Enable seccomp to safely compute untrusted bytecode"
1515 This kernel feature is useful for number crunching applications
1516 that may need to compute untrusted bytecode during their
1517 execution. By using pipes or other transports made available to
1518 the process as file descriptors supporting the read/write
1519 syscalls, it's possible to isolate those applications in
1520 their own address space using seccomp. Once seccomp is
1521 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1522 and the task is only allowed to execute a few safe syscalls
1523 defined by each seccomp mode.
1525 If unsure, say Y. Only embedded should say N here.
1527 config CC_STACKPROTECTOR
1528 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1530 This option turns on the -fstack-protector GCC feature. This
1531 feature puts, at the beginning of functions, a canary value on
1532 the stack just before the return address, and validates
1533 the value just before actually returning. Stack based buffer
1534 overflows (that need to overwrite this return address) now also
1535 overwrite the canary, which gets detected and the attack is then
1536 neutralized via a kernel panic.
1538 This feature requires gcc version 4.2 or above, or a distribution
1539 gcc with the feature backported. Older versions are automatically
1540 detected and for those versions, this configuration option is
1541 ignored. (and a warning is printed during bootup)
1543 source kernel/Kconfig.hz
1546 bool "kexec system call"
1548 kexec is a system call that implements the ability to shutdown your
1549 current kernel, and to start another kernel. It is like a reboot
1550 but it is independent of the system firmware. And like a reboot
1551 you can start any kernel with it, not just Linux.
1553 The name comes from the similarity to the exec system call.
1555 It is an ongoing process to be certain the hardware in a machine
1556 is properly shutdown, so do not be surprised if this code does not
1557 initially work for you. It may help to enable device hotplugging
1558 support. As of this writing the exact hardware interface is
1559 strongly in flux, so no good recommendation can be made.
1562 bool "kernel crash dumps"
1563 depends on X86_64 || (X86_32 && HIGHMEM)
1565 Generate crash dump after being started by kexec.
1566 This should be normally only set in special crash dump kernels
1567 which are loaded in the main kernel with kexec-tools into
1568 a specially reserved region and then later executed after
1569 a crash by kdump/kexec. The crash dump kernel must be compiled
1570 to a memory address not used by the main kernel or BIOS using
1571 PHYSICAL_START, or it must be built as a relocatable image
1572 (CONFIG_RELOCATABLE=y).
1573 For more details see Documentation/kdump/kdump.txt
1576 bool "kexec jump (EXPERIMENTAL)"
1577 depends on EXPERIMENTAL
1578 depends on KEXEC && HIBERNATION
1580 Jump between original kernel and kexeced kernel and invoke
1581 code in physical address mode via KEXEC
1583 config PHYSICAL_START
1584 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1587 This gives the physical address where the kernel is loaded.
1589 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1590 bzImage will decompress itself to above physical address and
1591 run from there. Otherwise, bzImage will run from the address where
1592 it has been loaded by the boot loader and will ignore above physical
1595 In normal kdump cases one does not have to set/change this option
1596 as now bzImage can be compiled as a completely relocatable image
1597 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1598 address. This option is mainly useful for the folks who don't want
1599 to use a bzImage for capturing the crash dump and want to use a
1600 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1601 to be specifically compiled to run from a specific memory area
1602 (normally a reserved region) and this option comes handy.
1604 So if you are using bzImage for capturing the crash dump,
1605 leave the value here unchanged to 0x1000000 and set
1606 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1607 for capturing the crash dump change this value to start of
1608 the reserved region. In other words, it can be set based on
1609 the "X" value as specified in the "crashkernel=YM@XM"
1610 command line boot parameter passed to the panic-ed
1611 kernel. Please take a look at Documentation/kdump/kdump.txt
1612 for more details about crash dumps.
1614 Usage of bzImage for capturing the crash dump is recommended as
1615 one does not have to build two kernels. Same kernel can be used
1616 as production kernel and capture kernel. Above option should have
1617 gone away after relocatable bzImage support is introduced. But it
1618 is present because there are users out there who continue to use
1619 vmlinux for dump capture. This option should go away down the
1622 Don't change this unless you know what you are doing.
1625 bool "Build a relocatable kernel"
1628 This builds a kernel image that retains relocation information
1629 so it can be loaded someplace besides the default 1MB.
1630 The relocations tend to make the kernel binary about 10% larger,
1631 but are discarded at runtime.
1633 One use is for the kexec on panic case where the recovery kernel
1634 must live at a different physical address than the primary
1637 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1638 it has been loaded at and the compile time physical address
1639 (CONFIG_PHYSICAL_START) is ignored.
1641 # Relocation on x86-32 needs some additional build support
1642 config X86_NEED_RELOCS
1644 depends on X86_32 && RELOCATABLE
1646 config PHYSICAL_ALIGN
1647 hex "Alignment value to which kernel should be aligned" if X86_32
1649 range 0x2000 0x1000000
1651 This value puts the alignment restrictions on physical address
1652 where kernel is loaded and run from. Kernel is compiled for an
1653 address which meets above alignment restriction.
1655 If bootloader loads the kernel at a non-aligned address and
1656 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1657 address aligned to above value and run from there.
1659 If bootloader loads the kernel at a non-aligned address and
1660 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1661 load address and decompress itself to the address it has been
1662 compiled for and run from there. The address for which kernel is
1663 compiled already meets above alignment restrictions. Hence the
1664 end result is that kernel runs from a physical address meeting
1665 above alignment restrictions.
1667 Don't change this unless you know what you are doing.
1670 bool "Support for hot-pluggable CPUs"
1671 depends on SMP && HOTPLUG
1673 Say Y here to allow turning CPUs off and on. CPUs can be
1674 controlled through /sys/devices/system/cpu.
1675 ( Note: power management support will enable this option
1676 automatically on SMP systems. )
1677 Say N if you want to disable CPU hotplug.
1681 prompt "Compat VDSO support"
1682 depends on X86_32 || IA32_EMULATION
1684 Map the 32-bit VDSO to the predictable old-style address too.
1686 Say N here if you are running a sufficiently recent glibc
1687 version (2.3.3 or later), to remove the high-mapped
1688 VDSO mapping and to exclusively use the randomized VDSO.
1693 bool "Built-in kernel command line"
1695 Allow for specifying boot arguments to the kernel at
1696 build time. On some systems (e.g. embedded ones), it is
1697 necessary or convenient to provide some or all of the
1698 kernel boot arguments with the kernel itself (that is,
1699 to not rely on the boot loader to provide them.)
1701 To compile command line arguments into the kernel,
1702 set this option to 'Y', then fill in the
1703 the boot arguments in CONFIG_CMDLINE.
1705 Systems with fully functional boot loaders (i.e. non-embedded)
1706 should leave this option set to 'N'.
1709 string "Built-in kernel command string"
1710 depends on CMDLINE_BOOL
1713 Enter arguments here that should be compiled into the kernel
1714 image and used at boot time. If the boot loader provides a
1715 command line at boot time, it is appended to this string to
1716 form the full kernel command line, when the system boots.
1718 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1719 change this behavior.
1721 In most cases, the command line (whether built-in or provided
1722 by the boot loader) should specify the device for the root
1725 config CMDLINE_OVERRIDE
1726 bool "Built-in command line overrides boot loader arguments"
1727 depends on CMDLINE_BOOL
1729 Set this option to 'Y' to have the kernel ignore the boot loader
1730 command line, and use ONLY the built-in command line.
1732 This is used to work around broken boot loaders. This should
1733 be set to 'N' under normal conditions.
1737 config ARCH_ENABLE_MEMORY_HOTPLUG
1739 depends on X86_64 || (X86_32 && HIGHMEM)
1741 config ARCH_ENABLE_MEMORY_HOTREMOVE
1743 depends on MEMORY_HOTPLUG
1745 config USE_PERCPU_NUMA_NODE_ID
1749 menu "Power management and ACPI options"
1751 config ARCH_HIBERNATION_HEADER
1753 depends on X86_64 && HIBERNATION
1755 source "kernel/power/Kconfig"
1757 source "drivers/acpi/Kconfig"
1759 source "drivers/sfi/Kconfig"
1766 tristate "APM (Advanced Power Management) BIOS support"
1767 depends on X86_32 && PM_SLEEP
1769 APM is a BIOS specification for saving power using several different
1770 techniques. This is mostly useful for battery powered laptops with
1771 APM compliant BIOSes. If you say Y here, the system time will be
1772 reset after a RESUME operation, the /proc/apm device will provide
1773 battery status information, and user-space programs will receive
1774 notification of APM "events" (e.g. battery status change).
1776 If you select "Y" here, you can disable actual use of the APM
1777 BIOS by passing the "apm=off" option to the kernel at boot time.
1779 Note that the APM support is almost completely disabled for
1780 machines with more than one CPU.
1782 In order to use APM, you will need supporting software. For location
1783 and more information, read <file:Documentation/power/apm-acpi.txt>
1784 and the Battery Powered Linux mini-HOWTO, available from
1785 <http://www.tldp.org/docs.html#howto>.
1787 This driver does not spin down disk drives (see the hdparm(8)
1788 manpage ("man 8 hdparm") for that), and it doesn't turn off
1789 VESA-compliant "green" monitors.
1791 This driver does not support the TI 4000M TravelMate and the ACER
1792 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1793 desktop machines also don't have compliant BIOSes, and this driver
1794 may cause those machines to panic during the boot phase.
1796 Generally, if you don't have a battery in your machine, there isn't
1797 much point in using this driver and you should say N. If you get
1798 random kernel OOPSes or reboots that don't seem to be related to
1799 anything, try disabling/enabling this option (or disabling/enabling
1802 Some other things you should try when experiencing seemingly random,
1805 1) make sure that you have enough swap space and that it is
1807 2) pass the "no-hlt" option to the kernel
1808 3) switch on floating point emulation in the kernel and pass
1809 the "no387" option to the kernel
1810 4) pass the "floppy=nodma" option to the kernel
1811 5) pass the "mem=4M" option to the kernel (thereby disabling
1812 all but the first 4 MB of RAM)
1813 6) make sure that the CPU is not over clocked.
1814 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1815 8) disable the cache from your BIOS settings
1816 9) install a fan for the video card or exchange video RAM
1817 10) install a better fan for the CPU
1818 11) exchange RAM chips
1819 12) exchange the motherboard.
1821 To compile this driver as a module, choose M here: the
1822 module will be called apm.
1826 config APM_IGNORE_USER_SUSPEND
1827 bool "Ignore USER SUSPEND"
1829 This option will ignore USER SUSPEND requests. On machines with a
1830 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1831 series notebooks, it is necessary to say Y because of a BIOS bug.
1833 config APM_DO_ENABLE
1834 bool "Enable PM at boot time"
1836 Enable APM features at boot time. From page 36 of the APM BIOS
1837 specification: "When disabled, the APM BIOS does not automatically
1838 power manage devices, enter the Standby State, enter the Suspend
1839 State, or take power saving steps in response to CPU Idle calls."
1840 This driver will make CPU Idle calls when Linux is idle (unless this
1841 feature is turned off -- see "Do CPU IDLE calls", below). This
1842 should always save battery power, but more complicated APM features
1843 will be dependent on your BIOS implementation. You may need to turn
1844 this option off if your computer hangs at boot time when using APM
1845 support, or if it beeps continuously instead of suspending. Turn
1846 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1847 T400CDT. This is off by default since most machines do fine without
1851 bool "Make CPU Idle calls when idle"
1853 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1854 On some machines, this can activate improved power savings, such as
1855 a slowed CPU clock rate, when the machine is idle. These idle calls
1856 are made after the idle loop has run for some length of time (e.g.,
1857 333 mS). On some machines, this will cause a hang at boot time or
1858 whenever the CPU becomes idle. (On machines with more than one CPU,
1859 this option does nothing.)
1861 config APM_DISPLAY_BLANK
1862 bool "Enable console blanking using APM"
1864 Enable console blanking using the APM. Some laptops can use this to
1865 turn off the LCD backlight when the screen blanker of the Linux
1866 virtual console blanks the screen. Note that this is only used by
1867 the virtual console screen blanker, and won't turn off the backlight
1868 when using the X Window system. This also doesn't have anything to
1869 do with your VESA-compliant power-saving monitor. Further, this
1870 option doesn't work for all laptops -- it might not turn off your
1871 backlight at all, or it might print a lot of errors to the console,
1872 especially if you are using gpm.
1874 config APM_ALLOW_INTS
1875 bool "Allow interrupts during APM BIOS calls"
1877 Normally we disable external interrupts while we are making calls to
1878 the APM BIOS as a measure to lessen the effects of a badly behaving
1879 BIOS implementation. The BIOS should reenable interrupts if it
1880 needs to. Unfortunately, some BIOSes do not -- especially those in
1881 many of the newer IBM Thinkpads. If you experience hangs when you
1882 suspend, try setting this to Y. Otherwise, say N.
1886 source "drivers/cpufreq/Kconfig"
1888 source "drivers/cpuidle/Kconfig"
1890 source "drivers/idle/Kconfig"
1895 menu "Bus options (PCI etc.)"
1900 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1902 Find out whether you have a PCI motherboard. PCI is the name of a
1903 bus system, i.e. the way the CPU talks to the other stuff inside
1904 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1905 VESA. If you have PCI, say Y, otherwise N.
1908 prompt "PCI access mode"
1909 depends on X86_32 && PCI
1912 On PCI systems, the BIOS can be used to detect the PCI devices and
1913 determine their configuration. However, some old PCI motherboards
1914 have BIOS bugs and may crash if this is done. Also, some embedded
1915 PCI-based systems don't have any BIOS at all. Linux can also try to
1916 detect the PCI hardware directly without using the BIOS.
1918 With this option, you can specify how Linux should detect the
1919 PCI devices. If you choose "BIOS", the BIOS will be used,
1920 if you choose "Direct", the BIOS won't be used, and if you
1921 choose "MMConfig", then PCI Express MMCONFIG will be used.
1922 If you choose "Any", the kernel will try MMCONFIG, then the
1923 direct access method and falls back to the BIOS if that doesn't
1924 work. If unsure, go with the default, which is "Any".
1929 config PCI_GOMMCONFIG
1946 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1948 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1951 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
1955 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
1959 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1963 depends on PCI && XEN
1971 bool "Support mmconfig PCI config space access"
1972 depends on X86_64 && PCI && ACPI
1974 config PCI_CNB20LE_QUIRK
1975 bool "Read CNB20LE Host Bridge Windows" if EXPERT
1977 depends on PCI && EXPERIMENTAL
1979 Read the PCI windows out of the CNB20LE host bridge. This allows
1980 PCI hotplug to work on systems with the CNB20LE chipset which do
1983 There's no public spec for this chipset, and this functionality
1984 is known to be incomplete.
1986 You should say N unless you know you need this.
1988 source "drivers/pci/pcie/Kconfig"
1990 source "drivers/pci/Kconfig"
1992 # x86_64 have no ISA slots, but can have ISA-style DMA.
1994 bool "ISA-style DMA support" if (X86_64 && EXPERT)
1997 Enables ISA-style DMA support for devices requiring such controllers.
2005 Find out whether you have ISA slots on your motherboard. ISA is the
2006 name of a bus system, i.e. the way the CPU talks to the other stuff
2007 inside your box. Other bus systems are PCI, EISA, MicroChannel
2008 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2009 newer boards don't support it. If you have ISA, say Y, otherwise N.
2015 The Extended Industry Standard Architecture (EISA) bus was
2016 developed as an open alternative to the IBM MicroChannel bus.
2018 The EISA bus provided some of the features of the IBM MicroChannel
2019 bus while maintaining backward compatibility with cards made for
2020 the older ISA bus. The EISA bus saw limited use between 1988 and
2021 1995 when it was made obsolete by the PCI bus.
2023 Say Y here if you are building a kernel for an EISA-based machine.
2027 source "drivers/eisa/Kconfig"
2030 tristate "NatSemi SCx200 support"
2032 This provides basic support for National Semiconductor's
2033 (now AMD's) Geode processors. The driver probes for the
2034 PCI-IDs of several on-chip devices, so its a good dependency
2035 for other scx200_* drivers.
2037 If compiled as a module, the driver is named scx200.
2039 config SCx200HR_TIMER
2040 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2044 This driver provides a clocksource built upon the on-chip
2045 27MHz high-resolution timer. Its also a workaround for
2046 NSC Geode SC-1100's buggy TSC, which loses time when the
2047 processor goes idle (as is done by the scheduler). The
2048 other workaround is idle=poll boot option.
2051 bool "One Laptop Per Child support"
2058 Add support for detecting the unique features of the OLPC
2062 bool "OLPC XO-1 Power Management"
2063 depends on OLPC && MFD_CS5535 && PM_SLEEP
2066 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2069 bool "OLPC XO-1 Real Time Clock"
2070 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2072 Add support for the XO-1 real time clock, which can be used as a
2073 programmable wakeup source.
2076 bool "OLPC XO-1 SCI extras"
2077 depends on OLPC && OLPC_XO1_PM
2082 Add support for SCI-based features of the OLPC XO-1 laptop:
2083 - EC-driven system wakeups
2087 - AC adapter status updates
2088 - Battery status updates
2090 config OLPC_XO15_SCI
2091 bool "OLPC XO-1.5 SCI extras"
2092 depends on OLPC && ACPI
2095 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2096 - EC-driven system wakeups
2097 - AC adapter status updates
2098 - Battery status updates
2101 bool "PCEngines ALIX System Support (LED setup)"
2104 This option enables system support for the PCEngines ALIX.
2105 At present this just sets up LEDs for GPIO control on
2106 ALIX2/3/6 boards. However, other system specific setup should
2109 Note: You must still enable the drivers for GPIO and LED support
2110 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2112 Note: You have to set alix.force=1 for boards with Award BIOS.
2115 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2118 This option enables system support for the Soekris Engineering net5501.
2121 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2125 This option enables system support for the Traverse Technologies GEOS.
2131 depends on CPU_SUP_AMD && PCI
2133 source "drivers/pcmcia/Kconfig"
2135 source "drivers/pci/hotplug/Kconfig"
2138 bool "RapidIO support"
2142 If you say Y here, the kernel will include drivers and
2143 infrastructure code to support RapidIO interconnect devices.
2145 source "drivers/rapidio/Kconfig"
2150 menu "Executable file formats / Emulations"
2152 source "fs/Kconfig.binfmt"
2154 config IA32_EMULATION
2155 bool "IA32 Emulation"
2157 select COMPAT_BINFMT_ELF
2159 Include code to run legacy 32-bit programs under a
2160 64-bit kernel. You should likely turn this on, unless you're
2161 100% sure that you don't have any 32-bit programs left.
2164 tristate "IA32 a.out support"
2165 depends on IA32_EMULATION
2167 Support old a.out binaries in the 32bit emulation.
2170 bool "x32 ABI for 64-bit mode (EXPERIMENTAL)"
2171 depends on X86_64 && IA32_EMULATION && EXPERIMENTAL
2173 Include code to run binaries for the x32 native 32-bit ABI
2174 for 64-bit processors. An x32 process gets access to the
2175 full 64-bit register file and wide data path while leaving
2176 pointers at 32 bits for smaller memory footprint.
2178 You will need a recent binutils (2.22 or later) with
2179 elf32_x86_64 support enabled to compile a kernel with this
2184 depends on IA32_EMULATION || X86_X32
2185 select ARCH_WANT_OLD_COMPAT_IPC
2187 config COMPAT_FOR_U64_ALIGNMENT
2191 config SYSVIPC_COMPAT
2193 depends on COMPAT && SYSVIPC
2197 depends on COMPAT && KEYS
2203 config HAVE_ATOMIC_IOMAP
2207 config HAVE_TEXT_POKE_SMP
2209 select STOP_MACHINE if SMP
2211 config X86_DEV_DMA_OPS
2213 depends on X86_64 || STA2X11
2215 config X86_DMA_REMAP
2219 source "net/Kconfig"
2221 source "drivers/Kconfig"
2223 source "drivers/firmware/Kconfig"
2227 source "arch/x86/Kconfig.debug"
2229 source "security/Kconfig"
2231 source "crypto/Kconfig"
2233 source "arch/x86/kvm/Kconfig"
2235 source "lib/Kconfig"
projects / platform / adaptation / renesas_rcar / renesas_kernel.git / blob