linux/arch/x86/Kconfig
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   1# Select 32 or 64 bit
   2config 64BIT
   3        bool "64-bit kernel" if ARCH = "x86"
   4        default ARCH != "i386"
   5        ---help---
   6          Say yes to build a 64-bit kernel - formerly known as x86_64
   7          Say no to build a 32-bit kernel - formerly known as i386
   8
   9config X86_32
  10        def_bool y
  11        depends on !64BIT
  12        select CLKSRC_I8253
  13        select HAVE_UID16
  14
  15config X86_64
  16        def_bool y
  17        depends on 64BIT
  18        select X86_DEV_DMA_OPS
  19
  20### Arch settings
  21config X86
  22        def_bool y
  23        select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
  24        select HAVE_AOUT if X86_32
  25        select HAVE_UNSTABLE_SCHED_CLOCK
  26        select ARCH_SUPPORTS_NUMA_BALANCING
  27        select ARCH_WANTS_PROT_NUMA_PROT_NONE
  28        select HAVE_IDE
  29        select HAVE_OPROFILE
  30        select HAVE_PCSPKR_PLATFORM
  31        select HAVE_PERF_EVENTS
  32        select HAVE_IOREMAP_PROT
  33        select HAVE_KPROBES
  34        select HAVE_MEMBLOCK
  35        select HAVE_MEMBLOCK_NODE_MAP
  36        select ARCH_DISCARD_MEMBLOCK
  37        select ARCH_WANT_OPTIONAL_GPIOLIB
  38        select ARCH_WANT_FRAME_POINTERS
  39        select HAVE_DMA_ATTRS
  40        select HAVE_DMA_CONTIGUOUS if !SWIOTLB
  41        select HAVE_KRETPROBES
  42        select HAVE_OPTPROBES
  43        select HAVE_KPROBES_ON_FTRACE
  44        select HAVE_FTRACE_MCOUNT_RECORD
  45        select HAVE_FENTRY if X86_64
  46        select HAVE_C_RECORDMCOUNT
  47        select HAVE_DYNAMIC_FTRACE
  48        select HAVE_DYNAMIC_FTRACE_WITH_REGS
  49        select HAVE_FUNCTION_TRACER
  50        select HAVE_FUNCTION_GRAPH_TRACER
  51        select HAVE_FUNCTION_GRAPH_FP_TEST
  52        select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  53        select HAVE_SYSCALL_TRACEPOINTS
  54        select SYSCTL_EXCEPTION_TRACE
  55        select HAVE_KVM
  56        select HAVE_ARCH_KGDB
  57        select HAVE_ARCH_TRACEHOOK
  58        select HAVE_GENERIC_DMA_COHERENT if X86_32
  59        select HAVE_EFFICIENT_UNALIGNED_ACCESS
  60        select USER_STACKTRACE_SUPPORT
  61        select HAVE_REGS_AND_STACK_ACCESS_API
  62        select HAVE_DMA_API_DEBUG
  63        select HAVE_KERNEL_GZIP
  64        select HAVE_KERNEL_BZIP2
  65        select HAVE_KERNEL_LZMA
  66        select HAVE_KERNEL_XZ
  67        select HAVE_KERNEL_LZO
  68        select HAVE_KERNEL_LZ4
  69        select HAVE_HW_BREAKPOINT
  70        select HAVE_MIXED_BREAKPOINTS_REGS
  71        select PERF_EVENTS
  72        select HAVE_PERF_EVENTS_NMI
  73        select HAVE_PERF_REGS
  74        select HAVE_PERF_USER_STACK_DUMP
  75        select HAVE_DEBUG_KMEMLEAK
  76        select ANON_INODES
  77        select HAVE_ALIGNED_STRUCT_PAGE if SLUB
  78        select HAVE_CMPXCHG_LOCAL
  79        select HAVE_CMPXCHG_DOUBLE
  80        select HAVE_ARCH_KMEMCHECK
  81        select HAVE_USER_RETURN_NOTIFIER
  82        select ARCH_BINFMT_ELF_RANDOMIZE_PIE
  83        select HAVE_ARCH_JUMP_LABEL
  84        select HAVE_TEXT_POKE_SMP
  85        select HAVE_GENERIC_HARDIRQS
  86        select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
  87        select SPARSE_IRQ
  88        select GENERIC_FIND_FIRST_BIT
  89        select GENERIC_IRQ_PROBE
  90        select GENERIC_PENDING_IRQ if SMP
  91        select GENERIC_IRQ_SHOW
  92        select GENERIC_CLOCKEVENTS_MIN_ADJUST
  93        select IRQ_FORCED_THREADING
  94        select USE_GENERIC_SMP_HELPERS if SMP
  95        select HAVE_BPF_JIT if X86_64
  96        select HAVE_ARCH_TRANSPARENT_HUGEPAGE
  97        select CLKEVT_I8253
  98        select ARCH_HAVE_NMI_SAFE_CMPXCHG
  99        select GENERIC_IOMAP
 100        select DCACHE_WORD_ACCESS
 101        select GENERIC_SMP_IDLE_THREAD
 102        select ARCH_WANT_IPC_PARSE_VERSION if X86_32
 103        select HAVE_ARCH_SECCOMP_FILTER
 104        select BUILDTIME_EXTABLE_SORT
 105        select GENERIC_CMOS_UPDATE
 106        select HAVE_ARCH_SOFT_DIRTY
 107        select CLOCKSOURCE_WATCHDOG
 108        select GENERIC_CLOCKEVENTS
 109        select ARCH_CLOCKSOURCE_DATA if X86_64
 110        select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
 111        select GENERIC_TIME_VSYSCALL if X86_64
 112        select KTIME_SCALAR if X86_32
 113        select GENERIC_STRNCPY_FROM_USER
 114        select GENERIC_STRNLEN_USER
 115        select HAVE_CONTEXT_TRACKING if X86_64
 116        select HAVE_IRQ_TIME_ACCOUNTING
 117        select VIRT_TO_BUS
 118        select MODULES_USE_ELF_REL if X86_32
 119        select MODULES_USE_ELF_RELA if X86_64
 120        select CLONE_BACKWARDS if X86_32
 121        select ARCH_USE_BUILTIN_BSWAP
 122        select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
 123        select OLD_SIGACTION if X86_32
 124        select COMPAT_OLD_SIGACTION if IA32_EMULATION
 125        select RTC_LIB
 126        select HAVE_DEBUG_STACKOVERFLOW
 127
 128config INSTRUCTION_DECODER
 129        def_bool y
 130        depends on KPROBES || PERF_EVENTS || UPROBES
 131
 132config OUTPUT_FORMAT
 133        string
 134        default "elf32-i386" if X86_32
 135        default "elf64-x86-64" if X86_64
 136
 137config ARCH_DEFCONFIG
 138        string
 139        default "arch/x86/configs/i386_defconfig" if X86_32
 140        default "arch/x86/configs/x86_64_defconfig" if X86_64
 141
 142config LOCKDEP_SUPPORT
 143        def_bool y
 144
 145config STACKTRACE_SUPPORT
 146        def_bool y
 147
 148config HAVE_LATENCYTOP_SUPPORT
 149        def_bool y
 150
 151config MMU
 152        def_bool y
 153
 154config SBUS
 155        bool
 156
 157config NEED_DMA_MAP_STATE
 158        def_bool y
 159        depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG
 160
 161config NEED_SG_DMA_LENGTH
 162        def_bool y
 163
 164config GENERIC_ISA_DMA
 165        def_bool y
 166        depends on ISA_DMA_API
 167
 168config GENERIC_BUG
 169        def_bool y
 170        depends on BUG
 171        select GENERIC_BUG_RELATIVE_POINTERS if X86_64
 172
 173config GENERIC_BUG_RELATIVE_POINTERS
 174        bool
 175
 176config GENERIC_HWEIGHT
 177        def_bool y
 178
 179config ARCH_MAY_HAVE_PC_FDC
 180        def_bool y
 181        depends on ISA_DMA_API
 182
 183config RWSEM_XCHGADD_ALGORITHM
 184        def_bool y
 185
 186config GENERIC_CALIBRATE_DELAY
 187        def_bool y
 188
 189config ARCH_HAS_CPU_RELAX
 190        def_bool y
 191
 192config ARCH_HAS_CACHE_LINE_SIZE
 193        def_bool y
 194
 195config ARCH_HAS_CPU_AUTOPROBE
 196        def_bool y
 197
 198config HAVE_SETUP_PER_CPU_AREA
 199        def_bool y
 200
 201config NEED_PER_CPU_EMBED_FIRST_CHUNK
 202        def_bool y
 203
 204config NEED_PER_CPU_PAGE_FIRST_CHUNK
 205        def_bool y
 206
 207config ARCH_HIBERNATION_POSSIBLE
 208        def_bool y
 209
 210config ARCH_SUSPEND_POSSIBLE
 211        def_bool y
 212
 213config ARCH_WANT_HUGE_PMD_SHARE
 214        def_bool y
 215
 216config ARCH_WANT_GENERAL_HUGETLB
 217        def_bool y
 218
 219config ZONE_DMA32
 220        bool
 221        default X86_64
 222
 223config AUDIT_ARCH
 224        bool
 225        default X86_64
 226
 227config ARCH_SUPPORTS_OPTIMIZED_INLINING
 228        def_bool y
 229
 230config ARCH_SUPPORTS_DEBUG_PAGEALLOC
 231        def_bool y
 232
 233config HAVE_INTEL_TXT
 234        def_bool y
 235        depends on INTEL_IOMMU && ACPI
 236
 237config X86_32_SMP
 238        def_bool y
 239        depends on X86_32 && SMP
 240
 241config X86_64_SMP
 242        def_bool y
 243        depends on X86_64 && SMP
 244
 245config X86_HT
 246        def_bool y
 247        depends on SMP
 248
 249config X86_32_LAZY_GS
 250        def_bool y
 251        depends on X86_32 && !CC_STACKPROTECTOR
 252
 253config ARCH_HWEIGHT_CFLAGS
 254        string
 255        default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
 256        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
 257
 258config ARCH_CPU_PROBE_RELEASE
 259        def_bool y
 260        depends on HOTPLUG_CPU
 261
 262config ARCH_SUPPORTS_UPROBES
 263        def_bool y
 264
 265source "init/Kconfig"
 266source "kernel/Kconfig.freezer"
 267
 268menu "Processor type and features"
 269
 270config ZONE_DMA
 271        bool "DMA memory allocation support" if EXPERT
 272        default y
 273        help
 274          DMA memory allocation support allows devices with less than 32-bit
 275          addressing to allocate within the first 16MB of address space.
 276          Disable if no such devices will be used.
 277
 278          If unsure, say Y.
 279
 280config SMP
 281        bool "Symmetric multi-processing support"
 282        ---help---
 283          This enables support for systems with more than one CPU. If you have
 284          a system with only one CPU, like most personal computers, say N. If
 285          you have a system with more than one CPU, say Y.
 286
 287          If you say N here, the kernel will run on single and multiprocessor
 288          machines, but will use only one CPU of a multiprocessor machine. If
 289          you say Y here, the kernel will run on many, but not all,
 290          singleprocessor machines. On a singleprocessor machine, the kernel
 291          will run faster if you say N here.
 292
 293          Note that if you say Y here and choose architecture "586" or
 294          "Pentium" under "Processor family", the kernel will not work on 486
 295          architectures. Similarly, multiprocessor kernels for the "PPro"
 296          architecture may not work on all Pentium based boards.
 297
 298          People using multiprocessor machines who say Y here should also say
 299          Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
 300          Management" code will be disabled if you say Y here.
 301
 302          See also <file:Documentation/x86/i386/IO-APIC.txt>,
 303          <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
 304          <http://www.tldp.org/docs.html#howto>.
 305
 306          If you don't know what to do here, say N.
 307
 308config X86_X2APIC
 309        bool "Support x2apic"
 310        depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
 311        ---help---
 312          This enables x2apic support on CPUs that have this feature.
 313
 314          This allows 32-bit apic IDs (so it can support very large systems),
 315          and accesses the local apic via MSRs not via mmio.
 316
 317          If you don't know what to do here, say N.
 318
 319config X86_MPPARSE
 320        bool "Enable MPS table" if ACPI || SFI
 321        default y
 322        depends on X86_LOCAL_APIC
 323        ---help---
 324          For old smp systems that do not have proper acpi support. Newer systems
 325          (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
 326
 327config X86_BIGSMP
 328        bool "Support for big SMP systems with more than 8 CPUs"
 329        depends on X86_32 && SMP
 330        ---help---
 331          This option is needed for the systems that have more than 8 CPUs
 332
 333config GOLDFISH
 334       def_bool y
 335       depends on X86_GOLDFISH
 336
 337if X86_32
 338config X86_EXTENDED_PLATFORM
 339        bool "Support for extended (non-PC) x86 platforms"
 340        default y
 341        ---help---
 342          If you disable this option then the kernel will only support
 343          standard PC platforms. (which covers the vast majority of
 344          systems out there.)
 345
 346          If you enable this option then you'll be able to select support
 347          for the following (non-PC) 32 bit x86 platforms:
 348                Goldfish (Android emulator)
 349                AMD Elan
 350                NUMAQ (IBM/Sequent)
 351                RDC R-321x SoC
 352                SGI 320/540 (Visual Workstation)
 353                STA2X11-based (e.g. Northville)
 354                Summit/EXA (IBM x440)
 355                Unisys ES7000 IA32 series
 356                Moorestown MID devices
 357
 358          If you have one of these systems, or if you want to build a
 359          generic distribution kernel, say Y here - otherwise say N.
 360endif
 361
 362if X86_64
 363config X86_EXTENDED_PLATFORM
 364        bool "Support for extended (non-PC) x86 platforms"
 365        default y
 366        ---help---
 367          If you disable this option then the kernel will only support
 368          standard PC platforms. (which covers the vast majority of
 369          systems out there.)
 370
 371          If you enable this option then you'll be able to select support
 372          for the following (non-PC) 64 bit x86 platforms:
 373                Numascale NumaChip
 374                ScaleMP vSMP
 375                SGI Ultraviolet
 376
 377          If you have one of these systems, or if you want to build a
 378          generic distribution kernel, say Y here - otherwise say N.
 379endif
 380# This is an alphabetically sorted list of 64 bit extended platforms
 381# Please maintain the alphabetic order if and when there are additions
 382config X86_NUMACHIP
 383        bool "Numascale NumaChip"
 384        depends on X86_64
 385        depends on X86_EXTENDED_PLATFORM
 386        depends on NUMA
 387        depends on SMP
 388        depends on X86_X2APIC
 389        depends on PCI_MMCONFIG
 390        ---help---
 391          Adds support for Numascale NumaChip large-SMP systems. Needed to
 392          enable more than ~168 cores.
 393          If you don't have one of these, you should say N here.
 394
 395config X86_VSMP
 396        bool "ScaleMP vSMP"
 397        select HYPERVISOR_GUEST
 398        select PARAVIRT
 399        depends on X86_64 && PCI
 400        depends on X86_EXTENDED_PLATFORM
 401        depends on SMP
 402        ---help---
 403          Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
 404          supposed to run on these EM64T-based machines.  Only choose this option
 405          if you have one of these machines.
 406
 407config X86_UV
 408        bool "SGI Ultraviolet"
 409        depends on X86_64
 410        depends on X86_EXTENDED_PLATFORM
 411        depends on NUMA
 412        depends on X86_X2APIC
 413        ---help---
 414          This option is needed in order to support SGI Ultraviolet systems.
 415          If you don't have one of these, you should say N here.
 416
 417# Following is an alphabetically sorted list of 32 bit extended platforms
 418# Please maintain the alphabetic order if and when there are additions
 419
 420config X86_GOLDFISH
 421       bool "Goldfish (Virtual Platform)"
 422       depends on X86_32
 423       depends on X86_EXTENDED_PLATFORM
 424       ---help---
 425         Enable support for the Goldfish virtual platform used primarily
 426         for Android development. Unless you are building for the Android
 427         Goldfish emulator say N here.
 428
 429config X86_INTEL_CE
 430        bool "CE4100 TV platform"
 431        depends on PCI
 432        depends on PCI_GODIRECT
 433        depends on X86_32
 434        depends on X86_EXTENDED_PLATFORM
 435        select X86_REBOOTFIXUPS
 436        select OF
 437        select OF_EARLY_FLATTREE
 438        select IRQ_DOMAIN
 439        ---help---
 440          Select for the Intel CE media processor (CE4100) SOC.
 441          This option compiles in support for the CE4100 SOC for settop
 442          boxes and media devices.
 443
 444config X86_WANT_INTEL_MID
 445        bool "Intel MID platform support"
 446        depends on X86_32
 447        depends on X86_EXTENDED_PLATFORM
 448        ---help---
 449          Select to build a kernel capable of supporting Intel MID platform
 450          systems which do not have the PCI legacy interfaces (Moorestown,
 451          Medfield). If you are building for a PC class system say N here.
 452
 453if X86_WANT_INTEL_MID
 454
 455config X86_INTEL_MID
 456        bool
 457
 458config X86_MDFLD
 459       bool "Medfield MID platform"
 460        depends on PCI
 461        depends on PCI_GOANY
 462        depends on X86_IO_APIC
 463        select X86_INTEL_MID
 464        select SFI
 465        select DW_APB_TIMER
 466        select APB_TIMER
 467        select I2C
 468        select SPI
 469        select INTEL_SCU_IPC
 470        select X86_PLATFORM_DEVICES
 471        select MFD_INTEL_MSIC
 472        ---help---
 473          Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin
 474          Internet Device(MID) platform. 
 475          Unlike standard x86 PCs, Medfield does not have many legacy devices
 476          nor standard legacy replacement devices/features. e.g. Medfield does
 477          not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
 478
 479endif
 480
 481config X86_INTEL_LPSS
 482        bool "Intel Low Power Subsystem Support"
 483        depends on ACPI
 484        select COMMON_CLK
 485        ---help---
 486          Select to build support for Intel Low Power Subsystem such as
 487          found on Intel Lynxpoint PCH. Selecting this option enables
 488          things like clock tree (common clock framework) which are needed
 489          by the LPSS peripheral drivers.
 490
 491config X86_RDC321X
 492        bool "RDC R-321x SoC"
 493        depends on X86_32
 494        depends on X86_EXTENDED_PLATFORM
 495        select M486
 496        select X86_REBOOTFIXUPS
 497        ---help---
 498          This option is needed for RDC R-321x system-on-chip, also known
 499          as R-8610-(G).
 500          If you don't have one of these chips, you should say N here.
 501
 502config X86_32_NON_STANDARD
 503        bool "Support non-standard 32-bit SMP architectures"
 504        depends on X86_32 && SMP
 505        depends on X86_EXTENDED_PLATFORM
 506        ---help---
 507          This option compiles in the NUMAQ, Summit, bigsmp, ES7000,
 508          STA2X11, default subarchitectures.  It is intended for a generic
 509          binary kernel. If you select them all, kernel will probe it
 510          one by one and will fallback to default.
 511
 512# Alphabetically sorted list of Non standard 32 bit platforms
 513
 514config X86_NUMAQ
 515        bool "NUMAQ (IBM/Sequent)"
 516        depends on X86_32_NON_STANDARD
 517        depends on PCI
 518        select NUMA
 519        select X86_MPPARSE
 520        ---help---
 521          This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
 522          NUMA multiquad box. This changes the way that processors are
 523          bootstrapped, and uses Clustered Logical APIC addressing mode instead
 524          of Flat Logical.  You will need a new lynxer.elf file to flash your
 525          firmware with - send email to <Martin.Bligh@us.ibm.com>.
 526
 527config X86_SUPPORTS_MEMORY_FAILURE
 528        def_bool y
 529        # MCE code calls memory_failure():
 530        depends on X86_MCE
 531        # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
 532        depends on !X86_NUMAQ
 533        # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
 534        depends on X86_64 || !SPARSEMEM
 535        select ARCH_SUPPORTS_MEMORY_FAILURE
 536
 537config X86_VISWS
 538        bool "SGI 320/540 (Visual Workstation)"
 539        depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
 540        depends on X86_32_NON_STANDARD
 541        ---help---
 542          The SGI Visual Workstation series is an IA32-based workstation
 543          based on SGI systems chips with some legacy PC hardware attached.
 544
 545          Say Y here to create a kernel to run on the SGI 320 or 540.
 546
 547          A kernel compiled for the Visual Workstation will run on general
 548          PCs as well. See <file:Documentation/sgi-visws.txt> for details.
 549
 550config STA2X11
 551        bool "STA2X11 Companion Chip Support"
 552        depends on X86_32_NON_STANDARD && PCI
 553        select X86_DEV_DMA_OPS
 554        select X86_DMA_REMAP
 555        select SWIOTLB
 556        select MFD_STA2X11
 557        select ARCH_REQUIRE_GPIOLIB
 558        default n
 559        ---help---
 560          This adds support for boards based on the STA2X11 IO-Hub,
 561          a.k.a. "ConneXt". The chip is used in place of the standard
 562          PC chipset, so all "standard" peripherals are missing. If this
 563          option is selected the kernel will still be able to boot on
 564          standard PC machines.
 565
 566config X86_SUMMIT
 567        bool "Summit/EXA (IBM x440)"
 568        depends on X86_32_NON_STANDARD
 569        ---help---
 570          This option is needed for IBM systems that use the Summit/EXA chipset.
 571          In particular, it is needed for the x440.
 572
 573config X86_ES7000
 574        bool "Unisys ES7000 IA32 series"
 575        depends on X86_32_NON_STANDARD && X86_BIGSMP
 576        ---help---
 577          Support for Unisys ES7000 systems.  Say 'Y' here if this kernel is
 578          supposed to run on an IA32-based Unisys ES7000 system.
 579
 580config X86_32_IRIS
 581        tristate "Eurobraille/Iris poweroff module"
 582        depends on X86_32
 583        ---help---
 584          The Iris machines from EuroBraille do not have APM or ACPI support
 585          to shut themselves down properly.  A special I/O sequence is
 586          needed to do so, which is what this module does at
 587          kernel shutdown.
 588
 589          This is only for Iris machines from EuroBraille.
 590
 591          If unused, say N.
 592
 593config SCHED_OMIT_FRAME_POINTER
 594        def_bool y
 595        prompt "Single-depth WCHAN output"
 596        depends on X86
 597        ---help---
 598          Calculate simpler /proc/<PID>/wchan values. If this option
 599          is disabled then wchan values will recurse back to the
 600          caller function. This provides more accurate wchan values,
 601          at the expense of slightly more scheduling overhead.
 602
 603          If in doubt, say "Y".
 604
 605menuconfig HYPERVISOR_GUEST
 606        bool "Linux guest support"
 607        ---help---
 608          Say Y here to enable options for running Linux under various hyper-
 609          visors. This option enables basic hypervisor detection and platform
 610          setup.
 611
 612          If you say N, all options in this submenu will be skipped and
 613          disabled, and Linux guest support won't be built in.
 614
 615if HYPERVISOR_GUEST
 616
 617config PARAVIRT
 618        bool "Enable paravirtualization code"
 619        ---help---
 620          This changes the kernel so it can modify itself when it is run
 621          under a hypervisor, potentially improving performance significantly
 622          over full virtualization.  However, when run without a hypervisor
 623          the kernel is theoretically slower and slightly larger.
 624
 625config PARAVIRT_DEBUG
 626        bool "paravirt-ops debugging"
 627        depends on PARAVIRT && DEBUG_KERNEL
 628        ---help---
 629          Enable to debug paravirt_ops internals.  Specifically, BUG if
 630          a paravirt_op is missing when it is called.
 631
 632config PARAVIRT_SPINLOCKS
 633        bool "Paravirtualization layer for spinlocks"
 634        depends on PARAVIRT && SMP
 635        ---help---
 636          Paravirtualized spinlocks allow a pvops backend to replace the
 637          spinlock implementation with something virtualization-friendly
 638          (for example, block the virtual CPU rather than spinning).
 639
 640          Unfortunately the downside is an up to 5% performance hit on
 641          native kernels, with various workloads.
 642
 643          If you are unsure how to answer this question, answer N.
 644
 645source "arch/x86/xen/Kconfig"
 646
 647config KVM_GUEST
 648        bool "KVM Guest support (including kvmclock)"
 649        depends on PARAVIRT
 650        select PARAVIRT_CLOCK
 651        default y
 652        ---help---
 653          This option enables various optimizations for running under the KVM
 654          hypervisor. It includes a paravirtualized clock, so that instead
 655          of relying on a PIT (or probably other) emulation by the
 656          underlying device model, the host provides the guest with
 657          timing infrastructure such as time of day, and system time
 658
 659source "arch/x86/lguest/Kconfig"
 660
 661config PARAVIRT_TIME_ACCOUNTING
 662        bool "Paravirtual steal time accounting"
 663        depends on PARAVIRT
 664        default n
 665        ---help---
 666          Select this option to enable fine granularity task steal time
 667          accounting. Time spent executing other tasks in parallel with
 668          the current vCPU is discounted from the vCPU power. To account for
 669          that, there can be a small performance impact.
 670
 671          If in doubt, say N here.
 672
 673config PARAVIRT_CLOCK
 674        bool
 675
 676endif #HYPERVISOR_GUEST
 677
 678config NO_BOOTMEM
 679        def_bool y
 680
 681config MEMTEST
 682        bool "Memtest"
 683        ---help---
 684          This option adds a kernel parameter 'memtest', which allows memtest
 685          to be set.
 686                memtest=0, mean disabled; -- default
 687                memtest=1, mean do 1 test pattern;
 688                ...
 689                memtest=4, mean do 4 test patterns.
 690          If you are unsure how to answer this question, answer N.
 691
 692config X86_SUMMIT_NUMA
 693        def_bool y
 694        depends on X86_32 && NUMA && X86_32_NON_STANDARD
 695
 696config X86_CYCLONE_TIMER
 697        def_bool y
 698        depends on X86_SUMMIT
 699
 700source "arch/x86/Kconfig.cpu"
 701
 702config HPET_TIMER
 703        def_bool X86_64
 704        prompt "HPET Timer Support" if X86_32
 705        ---help---
 706          Use the IA-PC HPET (High Precision Event Timer) to manage
 707          time in preference to the PIT and RTC, if a HPET is
 708          present.
 709          HPET is the next generation timer replacing legacy 8254s.
 710          The HPET provides a stable time base on SMP
 711          systems, unlike the TSC, but it is more expensive to access,
 712          as it is off-chip.  You can find the HPET spec at
 713          <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
 714
 715          You can safely choose Y here.  However, HPET will only be
 716          activated if the platform and the BIOS support this feature.
 717          Otherwise the 8254 will be used for timing services.
 718
 719          Choose N to continue using the legacy 8254 timer.
 720
 721config HPET_EMULATE_RTC
 722        def_bool y
 723        depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
 724
 725config APB_TIMER
 726       def_bool y if X86_INTEL_MID
 727       prompt "Intel MID APB Timer Support" if X86_INTEL_MID
 728       select DW_APB_TIMER
 729       depends on X86_INTEL_MID && SFI
 730       help
 731         APB timer is the replacement for 8254, HPET on X86 MID platforms.
 732         The APBT provides a stable time base on SMP
 733         systems, unlike the TSC, but it is more expensive to access,
 734         as it is off-chip. APB timers are always running regardless of CPU
 735         C states, they are used as per CPU clockevent device when possible.
 736
 737# Mark as expert because too many people got it wrong.
 738# The code disables itself when not needed.
 739config DMI
 740        default y
 741        bool "Enable DMI scanning" if EXPERT
 742        ---help---
 743          Enabled scanning of DMI to identify machine quirks. Say Y
 744          here unless you have verified that your setup is not
 745          affected by entries in the DMI blacklist. Required by PNP
 746          BIOS code.
 747
 748config GART_IOMMU
 749        bool "GART IOMMU support" if EXPERT
 750        default y
 751        select SWIOTLB
 752        depends on X86_64 && PCI && AMD_NB
 753        ---help---
 754          Support for full DMA access of devices with 32bit memory access only
 755          on systems with more than 3GB. This is usually needed for USB,
 756          sound, many IDE/SATA chipsets and some other devices.
 757          Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
 758          based hardware IOMMU and a software bounce buffer based IOMMU used
 759          on Intel systems and as fallback.
 760          The code is only active when needed (enough memory and limited
 761          device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
 762          too.
 763
 764config CALGARY_IOMMU
 765        bool "IBM Calgary IOMMU support"
 766        select SWIOTLB
 767        depends on X86_64 && PCI
 768        ---help---
 769          Support for hardware IOMMUs in IBM's xSeries x366 and x460
 770          systems. Needed to run systems with more than 3GB of memory
 771          properly with 32-bit PCI devices that do not support DAC
 772          (Double Address Cycle). Calgary also supports bus level
 773          isolation, where all DMAs pass through the IOMMU.  This
 774          prevents them from going anywhere except their intended
 775          destination. This catches hard-to-find kernel bugs and
 776          mis-behaving drivers and devices that do not use the DMA-API
 777          properly to set up their DMA buffers.  The IOMMU can be
 778          turned off at boot time with the iommu=off parameter.
 779          Normally the kernel will make the right choice by itself.
 780          If unsure, say Y.
 781
 782config CALGARY_IOMMU_ENABLED_BY_DEFAULT
 783        def_bool y
 784        prompt "Should Calgary be enabled by default?"
 785        depends on CALGARY_IOMMU
 786        ---help---
 787          Should Calgary be enabled by default? if you choose 'y', Calgary
 788          will be used (if it exists). If you choose 'n', Calgary will not be
 789          used even if it exists. If you choose 'n' and would like to use
 790          Calgary anyway, pass 'iommu=calgary' on the kernel command line.
 791          If unsure, say Y.
 792
 793# need this always selected by IOMMU for the VIA workaround
 794config SWIOTLB
 795        def_bool y if X86_64
 796        ---help---
 797          Support for software bounce buffers used on x86-64 systems
 798          which don't have a hardware IOMMU. Using this PCI devices
 799          which can only access 32-bits of memory can be used on systems
 800          with more than 3 GB of memory.
 801          If unsure, say Y.
 802
 803config IOMMU_HELPER
 804        def_bool y
 805        depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
 806
 807config MAXSMP
 808        bool "Enable Maximum number of SMP Processors and NUMA Nodes"
 809        depends on X86_64 && SMP && DEBUG_KERNEL
 810        select CPUMASK_OFFSTACK
 811        ---help---
 812          Enable maximum number of CPUS and NUMA Nodes for this architecture.
 813          If unsure, say N.
 814
 815config NR_CPUS
 816        int "Maximum number of CPUs" if SMP && !MAXSMP
 817        range 2 8 if SMP && X86_32 && !X86_BIGSMP
 818        range 2 512 if SMP && !MAXSMP
 819        default "1" if !SMP
 820        default "4096" if MAXSMP
 821        default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
 822        default "8" if SMP
 823        ---help---
 824          This allows you to specify the maximum number of CPUs which this
 825          kernel will support.  The maximum supported value is 512 and the
 826          minimum value which makes sense is 2.
 827
 828          This is purely to save memory - each supported CPU adds
 829          approximately eight kilobytes to the kernel image.
 830
 831config SCHED_SMT
 832        bool "SMT (Hyperthreading) scheduler support"
 833        depends on X86_HT
 834        ---help---
 835          SMT scheduler support improves the CPU scheduler's decision making
 836          when dealing with Intel Pentium 4 chips with HyperThreading at a
 837          cost of slightly increased overhead in some places. If unsure say
 838          N here.
 839
 840config SCHED_MC
 841        def_bool y
 842        prompt "Multi-core scheduler support"
 843        depends on X86_HT
 844        ---help---
 845          Multi-core scheduler support improves the CPU scheduler's decision
 846          making when dealing with multi-core CPU chips at a cost of slightly
 847          increased overhead in some places. If unsure say N here.
 848
 849source "kernel/Kconfig.preempt"
 850
 851config X86_UP_APIC
 852        bool "Local APIC support on uniprocessors"
 853        depends on X86_32 && !SMP && !X86_32_NON_STANDARD
 854        ---help---
 855          A local APIC (Advanced Programmable Interrupt Controller) is an
 856          integrated interrupt controller in the CPU. If you have a single-CPU
 857          system which has a processor with a local APIC, you can say Y here to
 858          enable and use it. If you say Y here even though your machine doesn't
 859          have a local APIC, then the kernel will still run with no slowdown at
 860          all. The local APIC supports CPU-generated self-interrupts (timer,
 861          performance counters), and the NMI watchdog which detects hard
 862          lockups.
 863
 864config X86_UP_IOAPIC
 865        bool "IO-APIC support on uniprocessors"
 866        depends on X86_UP_APIC
 867        ---help---
 868          An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
 869          SMP-capable replacement for PC-style interrupt controllers. Most
 870          SMP systems and many recent uniprocessor systems have one.
 871
 872          If you have a single-CPU system with an IO-APIC, you can say Y here
 873          to use it. If you say Y here even though your machine doesn't have
 874          an IO-APIC, then the kernel will still run with no slowdown at all.
 875
 876config X86_LOCAL_APIC
 877        def_bool y
 878        depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
 879
 880config X86_IO_APIC
 881        def_bool y
 882        depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC
 883
 884config X86_VISWS_APIC
 885        def_bool y
 886        depends on X86_32 && X86_VISWS
 887
 888config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
 889        bool "Reroute for broken boot IRQs"
 890        depends on X86_IO_APIC
 891        ---help---
 892          This option enables a workaround that fixes a source of
 893          spurious interrupts. This is recommended when threaded
 894          interrupt handling is used on systems where the generation of
 895          superfluous "boot interrupts" cannot be disabled.
 896
 897          Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
 898          entry in the chipset's IO-APIC is masked (as, e.g. the RT
 899          kernel does during interrupt handling). On chipsets where this
 900          boot IRQ generation cannot be disabled, this workaround keeps
 901          the original IRQ line masked so that only the equivalent "boot
 902          IRQ" is delivered to the CPUs. The workaround also tells the
 903          kernel to set up the IRQ handler on the boot IRQ line. In this
 904          way only one interrupt is delivered to the kernel. Otherwise
 905          the spurious second interrupt may cause the kernel to bring
 906          down (vital) interrupt lines.
 907
 908          Only affects "broken" chipsets. Interrupt sharing may be
 909          increased on these systems.
 910
 911config X86_MCE
 912        bool "Machine Check / overheating reporting"
 913        default y
 914        ---help---
 915          Machine Check support allows the processor to notify the
 916          kernel if it detects a problem (e.g. overheating, data corruption).
 917          The action the kernel takes depends on the severity of the problem,
 918          ranging from warning messages to halting the machine.
 919
 920config X86_MCE_INTEL
 921        def_bool y
 922        prompt "Intel MCE features"
 923        depends on X86_MCE && X86_LOCAL_APIC
 924        ---help---
 925           Additional support for intel specific MCE features such as
 926           the thermal monitor.
 927
 928config X86_MCE_AMD
 929        def_bool y
 930        prompt "AMD MCE features"
 931        depends on X86_MCE && X86_LOCAL_APIC
 932        ---help---
 933           Additional support for AMD specific MCE features such as
 934           the DRAM Error Threshold.
 935
 936config X86_ANCIENT_MCE
 937        bool "Support for old Pentium 5 / WinChip machine checks"
 938        depends on X86_32 && X86_MCE
 939        ---help---
 940          Include support for machine check handling on old Pentium 5 or WinChip
 941          systems. These typically need to be enabled explicitely on the command
 942          line.
 943
 944config X86_MCE_THRESHOLD
 945        depends on X86_MCE_AMD || X86_MCE_INTEL
 946        def_bool y
 947
 948config X86_MCE_INJECT
 949        depends on X86_MCE
 950        tristate "Machine check injector support"
 951        ---help---
 952          Provide support for injecting machine checks for testing purposes.
 953          If you don't know what a machine check is and you don't do kernel
 954          QA it is safe to say n.
 955
 956config X86_THERMAL_VECTOR
 957        def_bool y
 958        depends on X86_MCE_INTEL
 959
 960config VM86
 961        bool "Enable VM86 support" if EXPERT
 962        default y
 963        depends on X86_32
 964        ---help---
 965          This option is required by programs like DOSEMU to run 16-bit legacy
 966          code on X86 processors. It also may be needed by software like
 967          XFree86 to initialize some video cards via BIOS. Disabling this
 968          option saves about 6k.
 969
 970config TOSHIBA
 971        tristate "Toshiba Laptop support"
 972        depends on X86_32
 973        ---help---
 974          This adds a driver to safely access the System Management Mode of
 975          the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
 976          not work on models with a Phoenix BIOS. The System Management Mode
 977          is used to set the BIOS and power saving options on Toshiba portables.
 978
 979          For information on utilities to make use of this driver see the
 980          Toshiba Linux utilities web site at:
 981          <http://www.buzzard.org.uk/toshiba/>.
 982
 983          Say Y if you intend to run this kernel on a Toshiba portable.
 984          Say N otherwise.
 985
 986config I8K
 987        tristate "Dell laptop support"
 988        select HWMON
 989        ---help---
 990          This adds a driver to safely access the System Management Mode
 991          of the CPU on the Dell Inspiron 8000. The System Management Mode
 992          is used to read cpu temperature and cooling fan status and to
 993          control the fans on the I8K portables.
 994
 995          This driver has been tested only on the Inspiron 8000 but it may
 996          also work with other Dell laptops. You can force loading on other
 997          models by passing the parameter `force=1' to the module. Use at
 998          your own risk.
 999
1000          For information on utilities to make use of this driver see the
1001          I8K Linux utilities web site at:
1002          <http://people.debian.org/~dz/i8k/>
1003
1004          Say Y if you intend to run this kernel on a Dell Inspiron 8000.
1005          Say N otherwise.
1006
1007config X86_REBOOTFIXUPS
1008        bool "Enable X86 board specific fixups for reboot"
1009        depends on X86_32
1010        ---help---
1011          This enables chipset and/or board specific fixups to be done
1012          in order to get reboot to work correctly. This is only needed on
1013          some combinations of hardware and BIOS. The symptom, for which
1014          this config is intended, is when reboot ends with a stalled/hung
1015          system.
1016
1017          Currently, the only fixup is for the Geode machines using
1018          CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1019
1020          Say Y if you want to enable the fixup. Currently, it's safe to
1021          enable this option even if you don't need it.
1022          Say N otherwise.
1023
1024config MICROCODE
1025        tristate "CPU microcode loading support"
1026        select FW_LOADER
1027        ---help---
1028
1029          If you say Y here, you will be able to update the microcode on
1030          certain Intel and AMD processors. The Intel support is for the
1031          IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1032          Xeon etc. The AMD support is for families 0x10 and later. You will
1033          obviously need the actual microcode binary data itself which is not
1034          shipped with the Linux kernel.
1035
1036          This option selects the general module only, you need to select
1037          at least one vendor specific module as well.
1038
1039          To compile this driver as a module, choose M here: the module
1040          will be called microcode.
1041
1042config MICROCODE_INTEL
1043        bool "Intel microcode loading support"
1044        depends on MICROCODE
1045        default MICROCODE
1046        select FW_LOADER
1047        ---help---
1048          This options enables microcode patch loading support for Intel
1049          processors.
1050
1051          For latest news and information on obtaining all the required
1052          Intel ingredients for this driver, check:
1053          <http://www.urbanmyth.org/microcode/>.
1054
1055config MICROCODE_AMD
1056        bool "AMD microcode loading support"
1057        depends on MICROCODE
1058        select FW_LOADER
1059        ---help---
1060          If you select this option, microcode patch loading support for AMD
1061          processors will be enabled.
1062
1063config MICROCODE_OLD_INTERFACE
1064        def_bool y
1065        depends on MICROCODE
1066
1067config MICROCODE_INTEL_LIB
1068        def_bool y
1069        depends on MICROCODE_INTEL
1070
1071config MICROCODE_INTEL_EARLY
1072        def_bool n
1073
1074config MICROCODE_AMD_EARLY
1075        def_bool n
1076
1077config MICROCODE_EARLY
1078        bool "Early load microcode"
1079        depends on MICROCODE=y && BLK_DEV_INITRD
1080        select MICROCODE_INTEL_EARLY if MICROCODE_INTEL
1081        select MICROCODE_AMD_EARLY if MICROCODE_AMD
1082        default y
1083        help
1084          This option provides functionality to read additional microcode data
1085          at the beginning of initrd image. The data tells kernel to load
1086          microcode to CPU's as early as possible. No functional change if no
1087          microcode data is glued to the initrd, therefore it's safe to say Y.
1088
1089config X86_MSR
1090        tristate "/dev/cpu/*/msr - Model-specific register support"
1091        ---help---
1092          This device gives privileged processes access to the x86
1093          Model-Specific Registers (MSRs).  It is a character device with
1094          major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1095          MSR accesses are directed to a specific CPU on multi-processor
1096          systems.
1097
1098config X86_CPUID
1099        tristate "/dev/cpu/*/cpuid - CPU information support"
1100        ---help---
1101          This device gives processes access to the x86 CPUID instruction to
1102          be executed on a specific processor.  It is a character device
1103          with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1104          /dev/cpu/31/cpuid.
1105
1106choice
1107        prompt "High Memory Support"
1108        default HIGHMEM64G if X86_NUMAQ
1109        default HIGHMEM4G
1110        depends on X86_32
1111
1112config NOHIGHMEM
1113        bool "off"
1114        depends on !X86_NUMAQ
1115        ---help---
1116          Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1117          However, the address space of 32-bit x86 processors is only 4
1118          Gigabytes large. That means that, if you have a large amount of
1119          physical memory, not all of it can be "permanently mapped" by the
1120          kernel. The physical memory that's not permanently mapped is called
1121          "high memory".
1122
1123          If you are compiling a kernel which will never run on a machine with
1124          more than 1 Gigabyte total physical RAM, answer "off" here (default
1125          choice and suitable for most users). This will result in a "3GB/1GB"
1126          split: 3GB are mapped so that each process sees a 3GB virtual memory
1127          space and the remaining part of the 4GB virtual memory space is used
1128          by the kernel to permanently map as much physical memory as
1129          possible.
1130
1131          If the machine has between 1 and 4 Gigabytes physical RAM, then
1132          answer "4GB" here.
1133
1134          If more than 4 Gigabytes is used then answer "64GB" here. This
1135          selection turns Intel PAE (Physical Address Extension) mode on.
1136          PAE implements 3-level paging on IA32 processors. PAE is fully
1137          supported by Linux, PAE mode is implemented on all recent Intel
1138          processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1139          then the kernel will not boot on CPUs that don't support PAE!
1140
1141          The actual amount of total physical memory will either be
1142          auto detected or can be forced by using a kernel command line option
1143          such as "mem=256M". (Try "man bootparam" or see the documentation of
1144          your boot loader (lilo or loadlin) about how to pass options to the
1145          kernel at boot time.)
1146
1147          If unsure, say "off".
1148
1149config HIGHMEM4G
1150        bool "4GB"
1151        depends on !X86_NUMAQ
1152        ---help---
1153          Select this if you have a 32-bit processor and between 1 and 4
1154          gigabytes of physical RAM.
1155
1156config HIGHMEM64G
1157        bool "64GB"
1158        depends on !M486
1159        select X86_PAE
1160        ---help---
1161          Select this if you have a 32-bit processor and more than 4
1162          gigabytes of physical RAM.
1163
1164endchoice
1165
1166choice
1167        prompt "Memory split" if EXPERT
1168        default VMSPLIT_3G
1169        depends on X86_32
1170        ---help---
1171          Select the desired split between kernel and user memory.
1172
1173          If the address range available to the kernel is less than the
1174          physical memory installed, the remaining memory will be available
1175          as "high memory". Accessing high memory is a little more costly
1176          than low memory, as it needs to be mapped into the kernel first.
1177          Note that increasing the kernel address space limits the range
1178          available to user programs, making the address space there
1179          tighter.  Selecting anything other than the default 3G/1G split
1180          will also likely make your kernel incompatible with binary-only
1181          kernel modules.
1182
1183          If you are not absolutely sure what you are doing, leave this
1184          option alone!
1185
1186        config VMSPLIT_3G
1187                bool "3G/1G user/kernel split"
1188        config VMSPLIT_3G_OPT
1189                depends on !X86_PAE
1190                bool "3G/1G user/kernel split (for full 1G low memory)"
1191        config VMSPLIT_2G
1192                bool "2G/2G user/kernel split"
1193        config VMSPLIT_2G_OPT
1194                depends on !X86_PAE
1195                bool "2G/2G user/kernel split (for full 2G low memory)"
1196        config VMSPLIT_1G
1197                bool "1G/3G user/kernel split"
1198endchoice
1199
1200config PAGE_OFFSET
1201        hex
1202        default 0xB0000000 if VMSPLIT_3G_OPT
1203        default 0x80000000 if VMSPLIT_2G
1204        default 0x78000000 if VMSPLIT_2G_OPT
1205        default 0x40000000 if VMSPLIT_1G
1206        default 0xC0000000
1207        depends on X86_32
1208
1209config HIGHMEM
1210        def_bool y
1211        depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1212
1213config X86_PAE
1214        bool "PAE (Physical Address Extension) Support"
1215        depends on X86_32 && !HIGHMEM4G
1216        ---help---
1217          PAE is required for NX support, and furthermore enables
1218          larger swapspace support for non-overcommit purposes. It
1219          has the cost of more pagetable lookup overhead, and also
1220          consumes more pagetable space per process.
1221
1222config ARCH_PHYS_ADDR_T_64BIT
1223        def_bool y
1224        depends on X86_64 || X86_PAE
1225
1226config ARCH_DMA_ADDR_T_64BIT
1227        def_bool y
1228        depends on X86_64 || HIGHMEM64G
1229
1230config DIRECT_GBPAGES
1231        bool "Enable 1GB pages for kernel pagetables" if EXPERT
1232        default y
1233        depends on X86_64
1234        ---help---
1235          Allow the kernel linear mapping to use 1GB pages on CPUs that
1236          support it. This can improve the kernel's performance a tiny bit by
1237          reducing TLB pressure. If in doubt, say "Y".
1238
1239# Common NUMA Features
1240config NUMA
1241        bool "Numa Memory Allocation and Scheduler Support"
1242        depends on SMP
1243        depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI))
1244        default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1245        ---help---
1246          Enable NUMA (Non Uniform Memory Access) support.
1247
1248          The kernel will try to allocate memory used by a CPU on the
1249          local memory controller of the CPU and add some more
1250          NUMA awareness to the kernel.
1251
1252          For 64-bit this is recommended if the system is Intel Core i7
1253          (or later), AMD Opteron, or EM64T NUMA.
1254
1255          For 32-bit this is only needed on (rare) 32-bit-only platforms
1256          that support NUMA topologies, such as NUMAQ / Summit, or if you
1257          boot a 32-bit kernel on a 64-bit NUMA platform.
1258
1259          Otherwise, you should say N.
1260
1261comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1262        depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1263
1264config AMD_NUMA
1265        def_bool y
1266        prompt "Old style AMD Opteron NUMA detection"
1267        depends on X86_64 && NUMA && PCI
1268        ---help---
1269          Enable AMD NUMA node topology detection.  You should say Y here if
1270          you have a multi processor AMD system. This uses an old method to
1271          read the NUMA configuration directly from the builtin Northbridge
1272          of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1273          which also takes priority if both are compiled in.
1274
1275config X86_64_ACPI_NUMA
1276        def_bool y
1277        prompt "ACPI NUMA detection"
1278        depends on X86_64 && NUMA && ACPI && PCI
1279        select ACPI_NUMA
1280        ---help---
1281          Enable ACPI SRAT based node topology detection.
1282
1283# Some NUMA nodes have memory ranges that span
1284# other nodes.  Even though a pfn is valid and
1285# between a node's start and end pfns, it may not
1286# reside on that node.  See memmap_init_zone()
1287# for details.
1288config NODES_SPAN_OTHER_NODES
1289        def_bool y
1290        depends on X86_64_ACPI_NUMA
1291
1292config NUMA_EMU
1293        bool "NUMA emulation"
1294        depends on NUMA
1295        ---help---
1296          Enable NUMA emulation. A flat machine will be split
1297          into virtual nodes when booted with "numa=fake=N", where N is the
1298          number of nodes. This is only useful for debugging.
1299
1300config NODES_SHIFT
1301        int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1302        range 1 10
1303        default "10" if MAXSMP
1304        default "6" if X86_64
1305        default "4" if X86_NUMAQ
1306        default "3"
1307        depends on NEED_MULTIPLE_NODES
1308        ---help---
1309          Specify the maximum number of NUMA Nodes available on the target
1310          system.  Increases memory reserved to accommodate various tables.
1311
1312config ARCH_HAVE_MEMORY_PRESENT
1313        def_bool y
1314        depends on X86_32 && DISCONTIGMEM
1315
1316config NEED_NODE_MEMMAP_SIZE
1317        def_bool y
1318        depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1319
1320config ARCH_FLATMEM_ENABLE
1321        def_bool y
1322        depends on X86_32 && !NUMA
1323
1324config ARCH_DISCONTIGMEM_ENABLE
1325        def_bool y
1326        depends on NUMA && X86_32
1327
1328config ARCH_DISCONTIGMEM_DEFAULT
1329        def_bool y
1330        depends on NUMA && X86_32
1331
1332config ARCH_SPARSEMEM_ENABLE
1333        def_bool y
1334        depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1335        select SPARSEMEM_STATIC if X86_32
1336        select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1337
1338config ARCH_SPARSEMEM_DEFAULT
1339        def_bool y
1340        depends on X86_64
1341
1342config ARCH_SELECT_MEMORY_MODEL
1343        def_bool y
1344        depends on ARCH_SPARSEMEM_ENABLE
1345
1346config ARCH_MEMORY_PROBE
1347        def_bool y
1348        depends on X86_64 && MEMORY_HOTPLUG
1349
1350config ARCH_PROC_KCORE_TEXT
1351        def_bool y
1352        depends on X86_64 && PROC_KCORE
1353
1354config ILLEGAL_POINTER_VALUE
1355       hex
1356       default 0 if X86_32
1357       default 0xdead000000000000 if X86_64
1358
1359source "mm/Kconfig"
1360
1361config HIGHPTE
1362        bool "Allocate 3rd-level pagetables from highmem"
1363        depends on HIGHMEM
1364        ---help---
1365          The VM uses one page table entry for each page of physical memory.
1366          For systems with a lot of RAM, this can be wasteful of precious
1367          low memory.  Setting this option will put user-space page table
1368          entries in high memory.
1369
1370config X86_CHECK_BIOS_CORRUPTION
1371        bool "Check for low memory corruption"
1372        ---help---
1373          Periodically check for memory corruption in low memory, which
1374          is suspected to be caused by BIOS.  Even when enabled in the
1375          configuration, it is disabled at runtime.  Enable it by
1376          setting "memory_corruption_check=1" on the kernel command
1377          line.  By default it scans the low 64k of memory every 60
1378          seconds; see the memory_corruption_check_size and
1379          memory_corruption_check_period parameters in
1380          Documentation/kernel-parameters.txt to adjust this.
1381
1382          When enabled with the default parameters, this option has
1383          almost no overhead, as it reserves a relatively small amount
1384          of memory and scans it infrequently.  It both detects corruption
1385          and prevents it from affecting the running system.
1386
1387          It is, however, intended as a diagnostic tool; if repeatable
1388          BIOS-originated corruption always affects the same memory,
1389          you can use memmap= to prevent the kernel from using that
1390          memory.
1391
1392config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1393        bool "Set the default setting of memory_corruption_check"
1394        depends on X86_CHECK_BIOS_CORRUPTION
1395        default y
1396        ---help---
1397          Set whether the default state of memory_corruption_check is
1398          on or off.
1399
1400config X86_RESERVE_LOW
1401        int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1402        default 64
1403        range 4 640
1404        ---help---
1405          Specify the amount of low memory to reserve for the BIOS.
1406
1407          The first page contains BIOS data structures that the kernel
1408          must not use, so that page must always be reserved.
1409
1410          By default we reserve the first 64K of physical RAM, as a
1411          number of BIOSes are known to corrupt that memory range
1412          during events such as suspend/resume or monitor cable
1413          insertion, so it must not be used by the kernel.
1414
1415          You can set this to 4 if you are absolutely sure that you
1416          trust the BIOS to get all its memory reservations and usages
1417          right.  If you know your BIOS have problems beyond the
1418          default 64K area, you can set this to 640 to avoid using the
1419          entire low memory range.
1420
1421          If you have doubts about the BIOS (e.g. suspend/resume does
1422          not work or there's kernel crashes after certain hardware
1423          hotplug events) then you might want to enable
1424          X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1425          typical corruption patterns.
1426
1427          Leave this to the default value of 64 if you are unsure.
1428
1429config MATH_EMULATION
1430        bool
1431        prompt "Math emulation" if X86_32
1432        ---help---
1433          Linux can emulate a math coprocessor (used for floating point
1434          operations) if you don't have one. 486DX and Pentium processors have
1435          a math coprocessor built in, 486SX and 386 do not, unless you added
1436          a 487DX or 387, respectively. (The messages during boot time can
1437          give you some hints here ["man dmesg"].) Everyone needs either a
1438          coprocessor or this emulation.
1439
1440          If you don't have a math coprocessor, you need to say Y here; if you
1441          say Y here even though you have a coprocessor, the coprocessor will
1442          be used nevertheless. (This behavior can be changed with the kernel
1443          command line option "no387", which comes handy if your coprocessor
1444          is broken. Try "man bootparam" or see the documentation of your boot
1445          loader (lilo or loadlin) about how to pass options to the kernel at
1446          boot time.) This means that it is a good idea to say Y here if you
1447          intend to use this kernel on different machines.
1448
1449          More information about the internals of the Linux math coprocessor
1450          emulation can be found in <file:arch/x86/math-emu/README>.
1451
1452          If you are not sure, say Y; apart from resulting in a 66 KB bigger
1453          kernel, it won't hurt.
1454
1455config MTRR
1456        def_bool y
1457        prompt "MTRR (Memory Type Range Register) support" if EXPERT
1458        ---help---
1459          On Intel P6 family processors (Pentium Pro, Pentium II and later)
1460          the Memory Type Range Registers (MTRRs) may be used to control
1461          processor access to memory ranges. This is most useful if you have
1462          a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1463          allows bus write transfers to be combined into a larger transfer
1464          before bursting over the PCI/AGP bus. This can increase performance
1465          of image write operations 2.5 times or more. Saying Y here creates a
1466          /proc/mtrr file which may be used to manipulate your processor's
1467          MTRRs. Typically the X server should use this.
1468
1469          This code has a reasonably generic interface so that similar
1470          control registers on other processors can be easily supported
1471          as well:
1472
1473          The Cyrix 6x86, 6x86MX and M II processors have Address Range
1474          Registers (ARRs) which provide a similar functionality to MTRRs. For
1475          these, the ARRs are used to emulate the MTRRs.
1476          The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1477          MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1478          write-combining. All of these processors are supported by this code
1479          and it makes sense to say Y here if you have one of them.
1480
1481          Saying Y here also fixes a problem with buggy SMP BIOSes which only
1482          set the MTRRs for the boot CPU and not for the secondary CPUs. This
1483          can lead to all sorts of problems, so it's good to say Y here.
1484
1485          You can safely say Y even if your machine doesn't have MTRRs, you'll
1486          just add about 9 KB to your kernel.
1487
1488          See <file:Documentation/x86/mtrr.txt> for more information.
1489
1490config MTRR_SANITIZER
1491        def_bool y
1492        prompt "MTRR cleanup support"
1493        depends on MTRR
1494        ---help---
1495          Convert MTRR layout from continuous to discrete, so X drivers can
1496          add writeback entries.
1497
1498          Can be disabled with disable_mtrr_cleanup on the kernel command line.
1499          The largest mtrr entry size for a continuous block can be set with
1500          mtrr_chunk_size.
1501
1502          If unsure, say Y.
1503
1504config MTRR_SANITIZER_ENABLE_DEFAULT
1505        int "MTRR cleanup enable value (0-1)"
1506        range 0 1
1507        default "0"
1508        depends on MTRR_SANITIZER
1509        ---help---
1510          Enable mtrr cleanup default value
1511
1512config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1513        int "MTRR cleanup spare reg num (0-7)"
1514        range 0 7
1515        default "1"
1516        depends on MTRR_SANITIZER
1517        ---help---
1518          mtrr cleanup spare entries default, it can be changed via
1519          mtrr_spare_reg_nr=N on the kernel command line.
1520
1521config X86_PAT
1522        def_bool y
1523        prompt "x86 PAT support" if EXPERT
1524        depends on MTRR
1525        ---help---
1526          Use PAT attributes to setup page level cache control.
1527
1528          PATs are the modern equivalents of MTRRs and are much more
1529          flexible than MTRRs.
1530
1531          Say N here if you see bootup problems (boot crash, boot hang,
1532          spontaneous reboots) or a non-working video driver.
1533
1534          If unsure, say Y.
1535
1536config ARCH_USES_PG_UNCACHED
1537        def_bool y
1538        depends on X86_PAT
1539
1540config ARCH_RANDOM
1541        def_bool y
1542        prompt "x86 architectural random number generator" if EXPERT
1543        ---help---
1544          Enable the x86 architectural RDRAND instruction
1545          (Intel Bull Mountain technology) to generate random numbers.
1546          If supported, this is a high bandwidth, cryptographically
1547          secure hardware random number generator.
1548
1549config X86_SMAP
1550        def_bool y
1551        prompt "Supervisor Mode Access Prevention" if EXPERT
1552        ---help---
1553          Supervisor Mode Access Prevention (SMAP) is a security
1554          feature in newer Intel processors.  There is a small
1555          performance cost if this enabled and turned on; there is
1556          also a small increase in the kernel size if this is enabled.
1557
1558          If unsure, say Y.
1559
1560config EFI
1561        bool "EFI runtime service support"
1562        depends on ACPI
1563        select UCS2_STRING
1564        ---help---
1565          This enables the kernel to use EFI runtime services that are
1566          available (such as the EFI variable services).
1567
1568          This option is only useful on systems that have EFI firmware.
1569          In addition, you should use the latest ELILO loader available
1570          at <http://elilo.sourceforge.net> in order to take advantage
1571          of EFI runtime services. However, even with this option, the
1572          resultant kernel should continue to boot on existing non-EFI
1573          platforms.
1574
1575config EFI_STUB
1576       bool "EFI stub support"
1577       depends on EFI
1578       ---help---
1579          This kernel feature allows a bzImage to be loaded directly
1580          by EFI firmware without the use of a bootloader.
1581
1582          See Documentation/x86/efi-stub.txt for more information.
1583
1584config SECCOMP
1585        def_bool y
1586        prompt "Enable seccomp to safely compute untrusted bytecode"
1587        ---help---
1588          This kernel feature is useful for number crunching applications
1589          that may need to compute untrusted bytecode during their
1590          execution. By using pipes or other transports made available to
1591          the process as file descriptors supporting the read/write
1592          syscalls, it's possible to isolate those applications in
1593          their own address space using seccomp. Once seccomp is
1594          enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1595          and the task is only allowed to execute a few safe syscalls
1596          defined by each seccomp mode.
1597
1598          If unsure, say Y. Only embedded should say N here.
1599
1600config CC_STACKPROTECTOR
1601        bool "Enable -fstack-protector buffer overflow detection"
1602        ---help---
1603          This option turns on the -fstack-protector GCC feature. This
1604          feature puts, at the beginning of functions, a canary value on
1605          the stack just before the return address, and validates
1606          the value just before actually returning.  Stack based buffer
1607          overflows (that need to overwrite this return address) now also
1608          overwrite the canary, which gets detected and the attack is then
1609          neutralized via a kernel panic.
1610
1611          This feature requires gcc version 4.2 or above, or a distribution
1612          gcc with the feature backported. Older versions are automatically
1613          detected and for those versions, this configuration option is
1614          ignored. (and a warning is printed during bootup)
1615
1616source kernel/Kconfig.hz
1617
1618config KEXEC
1619        bool "kexec system call"
1620        ---help---
1621          kexec is a system call that implements the ability to shutdown your
1622          current kernel, and to start another kernel.  It is like a reboot
1623          but it is independent of the system firmware.   And like a reboot
1624          you can start any kernel with it, not just Linux.
1625
1626          The name comes from the similarity to the exec system call.
1627
1628          It is an ongoing process to be certain the hardware in a machine
1629          is properly shutdown, so do not be surprised if this code does not
1630          initially work for you.  It may help to enable device hotplugging
1631          support.  As of this writing the exact hardware interface is
1632          strongly in flux, so no good recommendation can be made.
1633
1634config CRASH_DUMP
1635        bool "kernel crash dumps"
1636        depends on X86_64 || (X86_32 && HIGHMEM)
1637        ---help---
1638          Generate crash dump after being started by kexec.
1639          This should be normally only set in special crash dump kernels
1640          which are loaded in the main kernel with kexec-tools into
1641          a specially reserved region and then later executed after
1642          a crash by kdump/kexec. The crash dump kernel must be compiled
1643          to a memory address not used by the main kernel or BIOS using
1644          PHYSICAL_START, or it must be built as a relocatable image
1645          (CONFIG_RELOCATABLE=y).
1646          For more details see Documentation/kdump/kdump.txt
1647
1648config KEXEC_JUMP
1649        bool "kexec jump"
1650        depends on KEXEC && HIBERNATION
1651        ---help---
1652          Jump between original kernel and kexeced kernel and invoke
1653          code in physical address mode via KEXEC
1654
1655config PHYSICAL_START
1656        hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1657        default "0x1000000"
1658        ---help---
1659          This gives the physical address where the kernel is loaded.
1660
1661          If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1662          bzImage will decompress itself to above physical address and
1663          run from there. Otherwise, bzImage will run from the address where
1664          it has been loaded by the boot loader and will ignore above physical
1665          address.
1666
1667          In normal kdump cases one does not have to set/change this option
1668          as now bzImage can be compiled as a completely relocatable image
1669          (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1670          address. This option is mainly useful for the folks who don't want
1671          to use a bzImage for capturing the crash dump and want to use a
1672          vmlinux instead. vmlinux is not relocatable hence a kernel needs
1673          to be specifically compiled to run from a specific memory area
1674          (normally a reserved region) and this option comes handy.
1675
1676          So if you are using bzImage for capturing the crash dump,
1677          leave the value here unchanged to 0x1000000 and set
1678          CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
1679          for capturing the crash dump change this value to start of
1680          the reserved region.  In other words, it can be set based on
1681          the "X" value as specified in the "crashkernel=YM@XM"
1682          command line boot parameter passed to the panic-ed
1683          kernel. Please take a look at Documentation/kdump/kdump.txt
1684          for more details about crash dumps.
1685
1686          Usage of bzImage for capturing the crash dump is recommended as
1687          one does not have to build two kernels. Same kernel can be used
1688          as production kernel and capture kernel. Above option should have
1689          gone away after relocatable bzImage support is introduced. But it
1690          is present because there are users out there who continue to use
1691          vmlinux for dump capture. This option should go away down the
1692          line.
1693
1694          Don't change this unless you know what you are doing.
1695
1696config RELOCATABLE
1697        bool "Build a relocatable kernel"
1698        default y
1699        ---help---
1700          This builds a kernel image that retains relocation information
1701          so it can be loaded someplace besides the default 1MB.
1702          The relocations tend to make the kernel binary about 10% larger,
1703          but are discarded at runtime.
1704
1705          One use is for the kexec on panic case where the recovery kernel
1706          must live at a different physical address than the primary
1707          kernel.
1708
1709          Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1710          it has been loaded at and the compile time physical address
1711          (CONFIG_PHYSICAL_START) is ignored.
1712
1713# Relocation on x86-32 needs some additional build support
1714config X86_NEED_RELOCS
1715        def_bool y
1716        depends on X86_32 && RELOCATABLE
1717
1718config PHYSICAL_ALIGN
1719        hex "Alignment value to which kernel should be aligned" if X86_32
1720        default "0x1000000"
1721        range 0x2000 0x1000000
1722        ---help---
1723          This value puts the alignment restrictions on physical address
1724          where kernel is loaded and run from. Kernel is compiled for an
1725          address which meets above alignment restriction.
1726
1727          If bootloader loads the kernel at a non-aligned address and
1728          CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1729          address aligned to above value and run from there.
1730
1731          If bootloader loads the kernel at a non-aligned address and
1732          CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1733          load address and decompress itself to the address it has been
1734          compiled for and run from there. The address for which kernel is
1735          compiled already meets above alignment restrictions. Hence the
1736          end result is that kernel runs from a physical address meeting
1737          above alignment restrictions.
1738
1739          Don't change this unless you know what you are doing.
1740
1741config HOTPLUG_CPU
1742        bool "Support for hot-pluggable CPUs"
1743        depends on SMP
1744        ---help---
1745          Say Y here to allow turning CPUs off and on. CPUs can be
1746          controlled through /sys/devices/system/cpu.
1747          ( Note: power management support will enable this option
1748            automatically on SMP systems. )
1749          Say N if you want to disable CPU hotplug.
1750
1751config BOOTPARAM_HOTPLUG_CPU0
1752        bool "Set default setting of cpu0_hotpluggable"
1753        default n
1754        depends on HOTPLUG_CPU
1755        ---help---
1756          Set whether default state of cpu0_hotpluggable is on or off.
1757
1758          Say Y here to enable CPU0 hotplug by default. If this switch
1759          is turned on, there is no need to give cpu0_hotplug kernel
1760          parameter and the CPU0 hotplug feature is enabled by default.
1761
1762          Please note: there are two known CPU0 dependencies if you want
1763          to enable the CPU0 hotplug feature either by this switch or by
1764          cpu0_hotplug kernel parameter.
1765
1766          First, resume from hibernate or suspend always starts from CPU0.
1767          So hibernate and suspend are prevented if CPU0 is offline.
1768
1769          Second dependency is PIC interrupts always go to CPU0. CPU0 can not
1770          offline if any interrupt can not migrate out of CPU0. There may
1771          be other CPU0 dependencies.
1772
1773          Please make sure the dependencies are under your control before
1774          you enable this feature.
1775
1776          Say N if you don't want to enable CPU0 hotplug feature by default.
1777          You still can enable the CPU0 hotplug feature at boot by kernel
1778          parameter cpu0_hotplug.
1779
1780config DEBUG_HOTPLUG_CPU0
1781        def_bool n
1782        prompt "Debug CPU0 hotplug"
1783        depends on HOTPLUG_CPU
1784        ---help---
1785          Enabling this option offlines CPU0 (if CPU0 can be offlined) as
1786          soon as possible and boots up userspace with CPU0 offlined. User
1787          can online CPU0 back after boot time.
1788
1789          To debug CPU0 hotplug, you need to enable CPU0 offline/online
1790          feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
1791          compilation or giving cpu0_hotplug kernel parameter at boot.
1792
1793          If unsure, say N.
1794
1795config COMPAT_VDSO
1796        def_bool y
1797        prompt "Compat VDSO support"
1798        depends on X86_32 || IA32_EMULATION
1799        ---help---
1800          Map the 32-bit VDSO to the predictable old-style address too.
1801
1802          Say N here if you are running a sufficiently recent glibc
1803          version (2.3.3 or later), to remove the high-mapped
1804          VDSO mapping and to exclusively use the randomized VDSO.
1805
1806          If unsure, say Y.
1807
1808config CMDLINE_BOOL
1809        bool "Built-in kernel command line"
1810        ---help---
1811          Allow for specifying boot arguments to the kernel at
1812          build time.  On some systems (e.g. embedded ones), it is
1813          necessary or convenient to provide some or all of the
1814          kernel boot arguments with the kernel itself (that is,
1815          to not rely on the boot loader to provide them.)
1816
1817          To compile command line arguments into the kernel,
1818          set this option to 'Y', then fill in the
1819          the boot arguments in CONFIG_CMDLINE.
1820
1821          Systems with fully functional boot loaders (i.e. non-embedded)
1822          should leave this option set to 'N'.
1823
1824config CMDLINE
1825        string "Built-in kernel command string"
1826        depends on CMDLINE_BOOL
1827        default ""
1828        ---help---
1829          Enter arguments here that should be compiled into the kernel
1830          image and used at boot time.  If the boot loader provides a
1831          command line at boot time, it is appended to this string to
1832          form the full kernel command line, when the system boots.
1833
1834          However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1835          change this behavior.
1836
1837          In most cases, the command line (whether built-in or provided
1838          by the boot loader) should specify the device for the root
1839          file system.
1840
1841config CMDLINE_OVERRIDE
1842        bool "Built-in command line overrides boot loader arguments"
1843        depends on CMDLINE_BOOL
1844        ---help---
1845          Set this option to 'Y' to have the kernel ignore the boot loader
1846          command line, and use ONLY the built-in command line.
1847
1848          This is used to work around broken boot loaders.  This should
1849          be set to 'N' under normal conditions.
1850
1851endmenu
1852
1853config ARCH_ENABLE_MEMORY_HOTPLUG
1854        def_bool y
1855        depends on X86_64 || (X86_32 && HIGHMEM)
1856
1857config ARCH_ENABLE_MEMORY_HOTREMOVE
1858        def_bool y
1859        depends on MEMORY_HOTPLUG
1860
1861config USE_PERCPU_NUMA_NODE_ID
1862        def_bool y
1863        depends on NUMA
1864
1865menu "Power management and ACPI options"
1866
1867config ARCH_HIBERNATION_HEADER
1868        def_bool y
1869        depends on X86_64 && HIBERNATION
1870
1871source "kernel/power/Kconfig"
1872
1873source "drivers/acpi/Kconfig"
1874
1875source "drivers/sfi/Kconfig"
1876
1877config X86_APM_BOOT
1878        def_bool y
1879        depends on APM
1880
1881menuconfig APM
1882        tristate "APM (Advanced Power Management) BIOS support"
1883        depends on X86_32 && PM_SLEEP
1884        ---help---
1885          APM is a BIOS specification for saving power using several different
1886          techniques. This is mostly useful for battery powered laptops with
1887          APM compliant BIOSes. If you say Y here, the system time will be
1888          reset after a RESUME operation, the /proc/apm device will provide
1889          battery status information, and user-space programs will receive
1890          notification of APM "events" (e.g. battery status change).
1891
1892          If you select "Y" here, you can disable actual use of the APM
1893          BIOS by passing the "apm=off" option to the kernel at boot time.
1894
1895          Note that the APM support is almost completely disabled for
1896          machines with more than one CPU.
1897
1898          In order to use APM, you will need supporting software. For location
1899          and more information, read <file:Documentation/power/apm-acpi.txt>
1900          and the Battery Powered Linux mini-HOWTO, available from
1901          <http://www.tldp.org/docs.html#howto>.
1902
1903          This driver does not spin down disk drives (see the hdparm(8)
1904          manpage ("man 8 hdparm") for that), and it doesn't turn off
1905          VESA-compliant "green" monitors.
1906
1907          This driver does not support the TI 4000M TravelMate and the ACER
1908          486/DX4/75 because they don't have compliant BIOSes. Many "green"
1909          desktop machines also don't have compliant BIOSes, and this driver
1910          may cause those machines to panic during the boot phase.
1911
1912          Generally, if you don't have a battery in your machine, there isn't
1913          much point in using this driver and you should say N. If you get
1914          random kernel OOPSes or reboots that don't seem to be related to
1915          anything, try disabling/enabling this option (or disabling/enabling
1916          APM in your BIOS).
1917
1918          Some other things you should try when experiencing seemingly random,
1919          "weird" problems:
1920
1921          1) make sure that you have enough swap space and that it is
1922          enabled.
1923          2) pass the "no-hlt" option to the kernel
1924          3) switch on floating point emulation in the kernel and pass
1925          the "no387" option to the kernel
1926          4) pass the "floppy=nodma" option to the kernel
1927          5) pass the "mem=4M" option to the kernel (thereby disabling
1928          all but the first 4 MB of RAM)
1929          6) make sure that the CPU is not over clocked.
1930          7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1931          8) disable the cache from your BIOS settings
1932          9) install a fan for the video card or exchange video RAM
1933          10) install a better fan for the CPU
1934          11) exchange RAM chips
1935          12) exchange the motherboard.
1936
1937          To compile this driver as a module, choose M here: the
1938          module will be called apm.
1939
1940if APM
1941
1942config APM_IGNORE_USER_SUSPEND
1943        bool "Ignore USER SUSPEND"
1944        ---help---
1945          This option will ignore USER SUSPEND requests. On machines with a
1946          compliant APM BIOS, you want to say N. However, on the NEC Versa M
1947          series notebooks, it is necessary to say Y because of a BIOS bug.
1948
1949config APM_DO_ENABLE
1950        bool "Enable PM at boot time"
1951        ---help---
1952          Enable APM features at boot time. From page 36 of the APM BIOS
1953          specification: "When disabled, the APM BIOS does not automatically
1954          power manage devices, enter the Standby State, enter the Suspend
1955          State, or take power saving steps in response to CPU Idle calls."
1956          This driver will make CPU Idle calls when Linux is idle (unless this
1957          feature is turned off -- see "Do CPU IDLE calls", below). This
1958          should always save battery power, but more complicated APM features
1959          will be dependent on your BIOS implementation. You may need to turn
1960          this option off if your computer hangs at boot time when using APM
1961          support, or if it beeps continuously instead of suspending. Turn
1962          this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1963          T400CDT. This is off by default since most machines do fine without
1964          this feature.
1965
1966config APM_CPU_IDLE
1967        depends on CPU_IDLE
1968        bool "Make CPU Idle calls when idle"
1969        ---help---
1970          Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1971          On some machines, this can activate improved power savings, such as
1972          a slowed CPU clock rate, when the machine is idle. These idle calls
1973          are made after the idle loop has run for some length of time (e.g.,
1974          333 mS). On some machines, this will cause a hang at boot time or
1975          whenever the CPU becomes idle. (On machines with more than one CPU,
1976          this option does nothing.)
1977
1978config APM_DISPLAY_BLANK
1979        bool "Enable console blanking using APM"
1980        ---help---
1981          Enable console blanking using the APM. Some laptops can use this to
1982          turn off the LCD backlight when the screen blanker of the Linux
1983          virtual console blanks the screen. Note that this is only used by
1984          the virtual console screen blanker, and won't turn off the backlight
1985          when using the X Window system. This also doesn't have anything to
1986          do with your VESA-compliant power-saving monitor. Further, this
1987          option doesn't work for all laptops -- it might not turn off your
1988          backlight at all, or it might print a lot of errors to the console,
1989          especially if you are using gpm.
1990
1991config APM_ALLOW_INTS
1992        bool "Allow interrupts during APM BIOS calls"
1993        ---help---
1994          Normally we disable external interrupts while we are making calls to
1995          the APM BIOS as a measure to lessen the effects of a badly behaving
1996          BIOS implementation.  The BIOS should reenable interrupts if it
1997          needs to.  Unfortunately, some BIOSes do not -- especially those in
1998          many of the newer IBM Thinkpads.  If you experience hangs when you
1999          suspend, try setting this to Y.  Otherwise, say N.
2000
2001endif # APM
2002
2003source "drivers/cpufreq/Kconfig"
2004
2005source "drivers/cpuidle/Kconfig"
2006
2007source "drivers/idle/Kconfig"
2008
2009endmenu
2010
2011
2012menu "Bus options (PCI etc.)"
2013
2014config PCI
2015        bool "PCI support"
2016        default y
2017        select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
2018        ---help---
2019          Find out whether you have a PCI motherboard. PCI is the name of a
2020          bus system, i.e. the way the CPU talks to the other stuff inside
2021          your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2022          VESA. If you have PCI, say Y, otherwise N.
2023
2024choice
2025        prompt "PCI access mode"
2026        depends on X86_32 && PCI
2027        default PCI_GOANY
2028        ---help---
2029          On PCI systems, the BIOS can be used to detect the PCI devices and
2030          determine their configuration. However, some old PCI motherboards
2031          have BIOS bugs and may crash if this is done. Also, some embedded
2032          PCI-based systems don't have any BIOS at all. Linux can also try to
2033          detect the PCI hardware directly without using the BIOS.
2034
2035          With this option, you can specify how Linux should detect the
2036          PCI devices. If you choose "BIOS", the BIOS will be used,
2037          if you choose "Direct", the BIOS won't be used, and if you
2038          choose "MMConfig", then PCI Express MMCONFIG will be used.
2039          If you choose "Any", the kernel will try MMCONFIG, then the
2040          direct access method and falls back to the BIOS if that doesn't
2041          work. If unsure, go with the default, which is "Any".
2042
2043config PCI_GOBIOS
2044        bool "BIOS"
2045
2046config PCI_GOMMCONFIG
2047        bool "MMConfig"
2048
2049config PCI_GODIRECT
2050        bool "Direct"
2051
2052config PCI_GOOLPC
2053        bool "OLPC XO-1"
2054        depends on OLPC
2055
2056config PCI_GOANY
2057        bool "Any"
2058
2059endchoice
2060
2061config PCI_BIOS
2062        def_bool y
2063        depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2064
2065# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2066config PCI_DIRECT
2067        def_bool y
2068        depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2069
2070config PCI_MMCONFIG
2071        def_bool y
2072        depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2073
2074config PCI_OLPC
2075        def_bool y
2076        depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2077
2078config PCI_XEN
2079        def_bool y
2080        depends on PCI && XEN
2081        select SWIOTLB_XEN
2082
2083config PCI_DOMAINS
2084        def_bool y
2085        depends on PCI
2086
2087config PCI_MMCONFIG
2088        bool "Support mmconfig PCI config space access"
2089        depends on X86_64 && PCI && ACPI
2090
2091config PCI_CNB20LE_QUIRK
2092        bool "Read CNB20LE Host Bridge Windows" if EXPERT
2093        depends on PCI
2094        help
2095          Read the PCI windows out of the CNB20LE host bridge. This allows
2096          PCI hotplug to work on systems with the CNB20LE chipset which do
2097          not have ACPI.
2098
2099          There's no public spec for this chipset, and this functionality
2100          is known to be incomplete.
2101
2102          You should say N unless you know you need this.
2103
2104source "drivers/pci/pcie/Kconfig"
2105
2106source "drivers/pci/Kconfig"
2107
2108# x86_64 have no ISA slots, but can have ISA-style DMA.
2109config ISA_DMA_API
2110        bool "ISA-style DMA support" if (X86_64 && EXPERT)
2111        default y
2112        help
2113          Enables ISA-style DMA support for devices requiring such controllers.
2114          If unsure, say Y.
2115
2116if X86_32
2117
2118config ISA
2119        bool "ISA support"
2120        ---help---
2121          Find out whether you have ISA slots on your motherboard.  ISA is the
2122          name of a bus system, i.e. the way the CPU talks to the other stuff
2123          inside your box.  Other bus systems are PCI, EISA, MicroChannel
2124          (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
2125          newer boards don't support it.  If you have ISA, say Y, otherwise N.
2126
2127config EISA
2128        bool "EISA support"
2129        depends on ISA
2130        ---help---
2131          The Extended Industry Standard Architecture (EISA) bus was
2132          developed as an open alternative to the IBM MicroChannel bus.
2133
2134          The EISA bus provided some of the features of the IBM MicroChannel
2135          bus while maintaining backward compatibility with cards made for
2136          the older ISA bus.  The EISA bus saw limited use between 1988 and
2137          1995 when it was made obsolete by the PCI bus.
2138
2139          Say Y here if you are building a kernel for an EISA-based machine.
2140
2141          Otherwise, say N.
2142
2143source "drivers/eisa/Kconfig"
2144
2145config SCx200
2146        tristate "NatSemi SCx200 support"
2147        ---help---
2148          This provides basic support for National Semiconductor's
2149          (now AMD's) Geode processors.  The driver probes for the
2150          PCI-IDs of several on-chip devices, so its a good dependency
2151          for other scx200_* drivers.
2152
2153          If compiled as a module, the driver is named scx200.
2154
2155config SCx200HR_TIMER
2156        tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2157        depends on SCx200
2158        default y
2159        ---help---
2160          This driver provides a clocksource built upon the on-chip
2161          27MHz high-resolution timer.  Its also a workaround for
2162          NSC Geode SC-1100's buggy TSC, which loses time when the
2163          processor goes idle (as is done by the scheduler).  The
2164          other workaround is idle=poll boot option.
2165
2166config OLPC
2167        bool "One Laptop Per Child support"
2168        depends on !X86_PAE
2169        select GPIOLIB
2170        select OF
2171        select OF_PROMTREE
2172        select IRQ_DOMAIN
2173        ---help---
2174          Add support for detecting the unique features of the OLPC
2175          XO hardware.
2176
2177config OLPC_XO1_PM
2178        bool "OLPC XO-1 Power Management"
2179        depends on OLPC && MFD_CS5535 && PM_SLEEP
2180        select MFD_CORE
2181        ---help---
2182          Add support for poweroff and suspend of the OLPC XO-1 laptop.
2183
2184config OLPC_XO1_RTC
2185        bool "OLPC XO-1 Real Time Clock"
2186        depends on OLPC_XO1_PM && RTC_DRV_CMOS
2187        ---help---
2188          Add support for the XO-1 real time clock, which can be used as a
2189          programmable wakeup source.
2190
2191config OLPC_XO1_SCI
2192        bool "OLPC XO-1 SCI extras"
2193        depends on OLPC && OLPC_XO1_PM
2194        depends on INPUT=y
2195        select POWER_SUPPLY
2196        select GPIO_CS5535
2197        select MFD_CORE
2198        ---help---
2199          Add support for SCI-based features of the OLPC XO-1 laptop:
2200           - EC-driven system wakeups
2201           - Power button
2202           - Ebook switch
2203           - Lid switch
2204           - AC adapter status updates
2205           - Battery status updates
2206
2207config OLPC_XO15_SCI
2208        bool "OLPC XO-1.5 SCI extras"
2209        depends on OLPC && ACPI
2210        select POWER_SUPPLY
2211        ---help---
2212          Add support for SCI-based features of the OLPC XO-1.5 laptop:
2213           - EC-driven system wakeups
2214           - AC adapter status updates
2215           - Battery status updates
2216
2217config ALIX
2218        bool "PCEngines ALIX System Support (LED setup)"
2219        select GPIOLIB
2220        ---help---
2221          This option enables system support for the PCEngines ALIX.
2222          At present this just sets up LEDs for GPIO control on
2223          ALIX2/3/6 boards.  However, other system specific setup should
2224          get added here.
2225
2226          Note: You must still enable the drivers for GPIO and LED support
2227          (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2228
2229          Note: You have to set alix.force=1 for boards with Award BIOS.
2230
2231config NET5501
2232        bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2233        select GPIOLIB
2234        ---help---
2235          This option enables system support for the Soekris Engineering net5501.
2236
2237config GEOS
2238        bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2239        select GPIOLIB
2240        depends on DMI
2241        ---help---
2242          This option enables system support for the Traverse Technologies GEOS.
2243
2244config TS5500
2245        bool "Technologic Systems TS-5500 platform support"
2246        depends on MELAN
2247        select CHECK_SIGNATURE
2248        select NEW_LEDS
2249        select LEDS_CLASS
2250        ---help---
2251          This option enables system support for the Technologic Systems TS-5500.
2252
2253endif # X86_32
2254
2255config AMD_NB
2256        def_bool y
2257        depends on CPU_SUP_AMD && PCI
2258
2259source "drivers/pcmcia/Kconfig"
2260
2261source "drivers/pci/hotplug/Kconfig"
2262
2263config RAPIDIO
2264        tristate "RapidIO support"
2265        depends on PCI
2266        default n
2267        help
2268          If enabled this option will include drivers and the core
2269          infrastructure code to support RapidIO interconnect devices.
2270
2271source "drivers/rapidio/Kconfig"
2272
2273endmenu
2274
2275
2276menu "Executable file formats / Emulations"
2277
2278source "fs/Kconfig.binfmt"
2279
2280config IA32_EMULATION
2281        bool "IA32 Emulation"
2282        depends on X86_64
2283        select BINFMT_ELF
2284        select COMPAT_BINFMT_ELF
2285        select HAVE_UID16
2286        ---help---
2287          Include code to run legacy 32-bit programs under a
2288          64-bit kernel. You should likely turn this on, unless you're
2289          100% sure that you don't have any 32-bit programs left.
2290
2291config IA32_AOUT
2292        tristate "IA32 a.out support"
2293        depends on IA32_EMULATION
2294        ---help---
2295          Support old a.out binaries in the 32bit emulation.
2296
2297config X86_X32
2298        bool "x32 ABI for 64-bit mode"
2299        depends on X86_64 && IA32_EMULATION
2300        ---help---
2301          Include code to run binaries for the x32 native 32-bit ABI
2302          for 64-bit processors.  An x32 process gets access to the
2303          full 64-bit register file and wide data path while leaving
2304          pointers at 32 bits for smaller memory footprint.
2305
2306          You will need a recent binutils (2.22 or later) with
2307          elf32_x86_64 support enabled to compile a kernel with this
2308          option set.
2309
2310config COMPAT
2311        def_bool y
2312        depends on IA32_EMULATION || X86_X32
2313        select ARCH_WANT_OLD_COMPAT_IPC
2314
2315if COMPAT
2316config COMPAT_FOR_U64_ALIGNMENT
2317        def_bool y
2318
2319config SYSVIPC_COMPAT
2320        def_bool y
2321        depends on SYSVIPC
2322
2323config KEYS_COMPAT
2324        def_bool y
2325        depends on KEYS
2326endif
2327
2328endmenu
2329
2330
2331config HAVE_ATOMIC_IOMAP
2332        def_bool y
2333        depends on X86_32
2334
2335config HAVE_TEXT_POKE_SMP
2336        bool
2337        select STOP_MACHINE if SMP
2338
2339config X86_DEV_DMA_OPS
2340        bool
2341        depends on X86_64 || STA2X11
2342
2343config X86_DMA_REMAP
2344        bool
2345        depends on STA2X11
2346
2347source "net/Kconfig"
2348
2349source "drivers/Kconfig"
2350
2351source "drivers/firmware/Kconfig"
2352
2353source "fs/Kconfig"
2354
2355source "arch/x86/Kconfig.debug"
2356
2357source "security/Kconfig"
2358
2359source "crypto/Kconfig"
2360
2361source "arch/x86/kvm/Kconfig"
2362
2363source "lib/Kconfig"
2364