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 = "x86_64"
   5        ---help---
   6          Say yes to build a 64-bit kernel - formerly known as x86_64
   7          Say no to build a 32-bit kernel - formerly known as i386
   8
   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 HAVE_AOUT if X86_32
  24        select HAVE_UNSTABLE_SCHED_CLOCK
  25        select HAVE_IDE
  26        select HAVE_OPROFILE
  27        select HAVE_PCSPKR_PLATFORM
  28        select HAVE_PERF_EVENTS
  29        select HAVE_IRQ_WORK
  30        select HAVE_IOREMAP_PROT
  31        select HAVE_KPROBES
  32        select HAVE_MEMBLOCK
  33        select HAVE_MEMBLOCK_NODE_MAP
  34        select ARCH_DISCARD_MEMBLOCK
  35        select ARCH_WANT_OPTIONAL_GPIOLIB
  36        select ARCH_WANT_FRAME_POINTERS
  37        select HAVE_DMA_ATTRS
  38        select HAVE_DMA_CONTIGUOUS if !SWIOTLB
  39        select HAVE_KRETPROBES
  40        select HAVE_OPTPROBES
  41        select HAVE_FTRACE_MCOUNT_RECORD
  42        select HAVE_FENTRY if X86_64
  43        select HAVE_C_RECORDMCOUNT
  44        select HAVE_DYNAMIC_FTRACE
  45        select HAVE_FUNCTION_TRACER
  46        select HAVE_FUNCTION_GRAPH_TRACER
  47        select HAVE_FUNCTION_GRAPH_FP_TEST
  48        select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  49        select HAVE_SYSCALL_TRACEPOINTS
  50        select SYSCTL_EXCEPTION_TRACE
  51        select HAVE_KVM
  52        select HAVE_ARCH_KGDB
  53        select HAVE_ARCH_TRACEHOOK
  54        select HAVE_GENERIC_DMA_COHERENT if X86_32
  55        select HAVE_EFFICIENT_UNALIGNED_ACCESS
  56        select USER_STACKTRACE_SUPPORT
  57        select HAVE_REGS_AND_STACK_ACCESS_API
  58        select HAVE_DMA_API_DEBUG
  59        select HAVE_KERNEL_GZIP
  60        select HAVE_KERNEL_BZIP2
  61        select HAVE_KERNEL_LZMA
  62        select HAVE_KERNEL_XZ
  63        select HAVE_KERNEL_LZO
  64        select HAVE_HW_BREAKPOINT
  65        select HAVE_MIXED_BREAKPOINTS_REGS
  66        select PERF_EVENTS
  67        select HAVE_PERF_EVENTS_NMI
  68        select HAVE_PERF_REGS
  69        select HAVE_PERF_USER_STACK_DUMP
  70        select HAVE_DEBUG_KMEMLEAK
  71        select ANON_INODES
  72        select HAVE_ALIGNED_STRUCT_PAGE if SLUB && !M386
  73        select HAVE_CMPXCHG_LOCAL if !M386
  74        select HAVE_CMPXCHG_DOUBLE
  75        select HAVE_ARCH_KMEMCHECK
  76        select HAVE_USER_RETURN_NOTIFIER
  77        select ARCH_BINFMT_ELF_RANDOMIZE_PIE
  78        select HAVE_ARCH_JUMP_LABEL
  79        select HAVE_TEXT_POKE_SMP
  80        select HAVE_GENERIC_HARDIRQS
  81        select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
  82        select SPARSE_IRQ
  83        select GENERIC_FIND_FIRST_BIT
  84        select GENERIC_IRQ_PROBE
  85        select GENERIC_PENDING_IRQ if SMP
  86        select GENERIC_IRQ_SHOW
  87        select GENERIC_CLOCKEVENTS_MIN_ADJUST
  88        select IRQ_FORCED_THREADING
  89        select USE_GENERIC_SMP_HELPERS if SMP
  90        select HAVE_BPF_JIT if X86_64
  91        select HAVE_ARCH_TRANSPARENT_HUGEPAGE
  92        select CLKEVT_I8253
  93        select ARCH_HAVE_NMI_SAFE_CMPXCHG
  94        select GENERIC_IOMAP
  95        select DCACHE_WORD_ACCESS
  96        select GENERIC_SMP_IDLE_THREAD
  97        select ARCH_WANT_IPC_PARSE_VERSION if X86_32
  98        select HAVE_ARCH_SECCOMP_FILTER
  99        select BUILDTIME_EXTABLE_SORT
 100        select GENERIC_CMOS_UPDATE
 101        select CLOCKSOURCE_WATCHDOG
 102        select GENERIC_CLOCKEVENTS
 103        select ARCH_CLOCKSOURCE_DATA if X86_64
 104        select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
 105        select GENERIC_TIME_VSYSCALL if X86_64
 106        select KTIME_SCALAR if X86_32
 107        select GENERIC_STRNCPY_FROM_USER
 108        select GENERIC_STRNLEN_USER
 109        select HAVE_RCU_USER_QS if X86_64
 110        select HAVE_IRQ_TIME_ACCOUNTING
 111        select GENERIC_KERNEL_THREAD
 112        select GENERIC_KERNEL_EXECVE
 113        select MODULES_USE_ELF_REL if X86_32
 114        select MODULES_USE_ELF_RELA if X86_64
 115
 116config INSTRUCTION_DECODER
 117        def_bool y
 118        depends on KPROBES || PERF_EVENTS || UPROBES
 119
 120config OUTPUT_FORMAT
 121        string
 122        default "elf32-i386" if X86_32
 123        default "elf64-x86-64" if X86_64
 124
 125config ARCH_DEFCONFIG
 126        string
 127        default "arch/x86/configs/i386_defconfig" if X86_32
 128        default "arch/x86/configs/x86_64_defconfig" if X86_64
 129
 130config LOCKDEP_SUPPORT
 131        def_bool y
 132
 133config STACKTRACE_SUPPORT
 134        def_bool y
 135
 136config HAVE_LATENCYTOP_SUPPORT
 137        def_bool y
 138
 139config MMU
 140        def_bool y
 141
 142config SBUS
 143        bool
 144
 145config NEED_DMA_MAP_STATE
 146        def_bool y
 147        depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG
 148
 149config NEED_SG_DMA_LENGTH
 150        def_bool y
 151
 152config GENERIC_ISA_DMA
 153        def_bool y
 154        depends on ISA_DMA_API
 155
 156config GENERIC_BUG
 157        def_bool y
 158        depends on BUG
 159        select GENERIC_BUG_RELATIVE_POINTERS if X86_64
 160
 161config GENERIC_BUG_RELATIVE_POINTERS
 162        bool
 163
 164config GENERIC_HWEIGHT
 165        def_bool y
 166
 167config GENERIC_GPIO
 168        bool
 169
 170config ARCH_MAY_HAVE_PC_FDC
 171        def_bool y
 172        depends on ISA_DMA_API
 173
 174config RWSEM_GENERIC_SPINLOCK
 175        def_bool y
 176        depends on !X86_XADD
 177
 178config RWSEM_XCHGADD_ALGORITHM
 179        def_bool y
 180        depends on X86_XADD
 181
 182config GENERIC_CALIBRATE_DELAY
 183        def_bool y
 184
 185config ARCH_HAS_CPU_RELAX
 186        def_bool y
 187
 188config ARCH_HAS_DEFAULT_IDLE
 189        def_bool y
 190
 191config ARCH_HAS_CACHE_LINE_SIZE
 192        def_bool y
 193
 194config ARCH_HAS_CPU_AUTOPROBE
 195        def_bool y
 196
 197config HAVE_SETUP_PER_CPU_AREA
 198        def_bool y
 199
 200config NEED_PER_CPU_EMBED_FIRST_CHUNK
 201        def_bool y
 202
 203config NEED_PER_CPU_PAGE_FIRST_CHUNK
 204        def_bool y
 205
 206config ARCH_HIBERNATION_POSSIBLE
 207        def_bool y
 208
 209config ARCH_SUSPEND_POSSIBLE
 210        def_bool y
 211
 212config ZONE_DMA32
 213        bool
 214        default X86_64
 215
 216config AUDIT_ARCH
 217        bool
 218        default X86_64
 219
 220config ARCH_SUPPORTS_OPTIMIZED_INLINING
 221        def_bool y
 222
 223config ARCH_SUPPORTS_DEBUG_PAGEALLOC
 224        def_bool y
 225
 226config HAVE_INTEL_TXT
 227        def_bool y
 228        depends on EXPERIMENTAL && INTEL_IOMMU && ACPI
 229
 230config X86_32_SMP
 231        def_bool y
 232        depends on X86_32 && SMP
 233
 234config X86_64_SMP
 235        def_bool y
 236        depends on X86_64 && SMP
 237
 238config X86_HT
 239        def_bool y
 240        depends on SMP
 241
 242config X86_32_LAZY_GS
 243        def_bool y
 244        depends on X86_32 && !CC_STACKPROTECTOR
 245
 246config ARCH_HWEIGHT_CFLAGS
 247        string
 248        default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
 249        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
 250
 251config ARCH_CPU_PROBE_RELEASE
 252        def_bool y
 253        depends on HOTPLUG_CPU
 254
 255config ARCH_SUPPORTS_UPROBES
 256        def_bool y
 257
 258source "init/Kconfig"
 259source "kernel/Kconfig.freezer"
 260
 261menu "Processor type and features"
 262
 263config ZONE_DMA
 264        bool "DMA memory allocation support" if EXPERT
 265        default y
 266        help
 267          DMA memory allocation support allows devices with less than 32-bit
 268          addressing to allocate within the first 16MB of address space.
 269          Disable if no such devices will be used.
 270
 271          If unsure, say Y.
 272
 273config SMP
 274        bool "Symmetric multi-processing support"
 275        ---help---
 276          This enables support for systems with more than one CPU. If you have
 277          a system with only one CPU, like most personal computers, say N. If
 278          you have a system with more than one CPU, say Y.
 279
 280          If you say N here, the kernel will run on single and multiprocessor
 281          machines, but will use only one CPU of a multiprocessor machine. If
 282          you say Y here, the kernel will run on many, but not all,
 283          singleprocessor machines. On a singleprocessor machine, the kernel
 284          will run faster if you say N here.
 285
 286          Note that if you say Y here and choose architecture "586" or
 287          "Pentium" under "Processor family", the kernel will not work on 486
 288          architectures. Similarly, multiprocessor kernels for the "PPro"
 289          architecture may not work on all Pentium based boards.
 290
 291          People using multiprocessor machines who say Y here should also say
 292          Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
 293          Management" code will be disabled if you say Y here.
 294
 295          See also <file:Documentation/x86/i386/IO-APIC.txt>,
 296          <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
 297          <http://www.tldp.org/docs.html#howto>.
 298
 299          If you don't know what to do here, say N.
 300
 301config X86_X2APIC
 302        bool "Support x2apic"
 303        depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
 304        ---help---
 305          This enables x2apic support on CPUs that have this feature.
 306
 307          This allows 32-bit apic IDs (so it can support very large systems),
 308          and accesses the local apic via MSRs not via mmio.
 309
 310          If you don't know what to do here, say N.
 311
 312config X86_MPPARSE
 313        bool "Enable MPS table" if ACPI
 314        default y
 315        depends on X86_LOCAL_APIC
 316        ---help---
 317          For old smp systems that do not have proper acpi support. Newer systems
 318          (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
 319
 320config X86_BIGSMP
 321        bool "Support for big SMP systems with more than 8 CPUs"
 322        depends on X86_32 && SMP
 323        ---help---
 324          This option is needed for the systems that have more than 8 CPUs
 325
 326if X86_32
 327config X86_EXTENDED_PLATFORM
 328        bool "Support for extended (non-PC) x86 platforms"
 329        default y
 330        ---help---
 331          If you disable this option then the kernel will only support
 332          standard PC platforms. (which covers the vast majority of
 333          systems out there.)
 334
 335          If you enable this option then you'll be able to select support
 336          for the following (non-PC) 32 bit x86 platforms:
 337                AMD Elan
 338                NUMAQ (IBM/Sequent)
 339                RDC R-321x SoC
 340                SGI 320/540 (Visual Workstation)
 341                STA2X11-based (e.g. Northville)
 342                Summit/EXA (IBM x440)
 343                Unisys ES7000 IA32 series
 344                Moorestown MID devices
 345
 346          If you have one of these systems, or if you want to build a
 347          generic distribution kernel, say Y here - otherwise say N.
 348endif
 349
 350if X86_64
 351config X86_EXTENDED_PLATFORM
 352        bool "Support for extended (non-PC) x86 platforms"
 353        default y
 354        ---help---
 355          If you disable this option then the kernel will only support
 356          standard PC platforms. (which covers the vast majority of
 357          systems out there.)
 358
 359          If you enable this option then you'll be able to select support
 360          for the following (non-PC) 64 bit x86 platforms:
 361                Numascale NumaChip
 362                ScaleMP vSMP
 363                SGI Ultraviolet
 364
 365          If you have one of these systems, or if you want to build a
 366          generic distribution kernel, say Y here - otherwise say N.
 367endif
 368# This is an alphabetically sorted list of 64 bit extended platforms
 369# Please maintain the alphabetic order if and when there are additions
 370config X86_NUMACHIP
 371        bool "Numascale NumaChip"
 372        depends on X86_64
 373        depends on X86_EXTENDED_PLATFORM
 374        depends on NUMA
 375        depends on SMP
 376        depends on X86_X2APIC
 377        ---help---
 378          Adds support for Numascale NumaChip large-SMP systems. Needed to
 379          enable more than ~168 cores.
 380          If you don't have one of these, you should say N here.
 381
 382config X86_VSMP
 383        bool "ScaleMP vSMP"
 384        select PARAVIRT_GUEST
 385        select PARAVIRT
 386        depends on X86_64 && PCI
 387        depends on X86_EXTENDED_PLATFORM
 388        depends on SMP
 389        ---help---
 390          Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
 391          supposed to run on these EM64T-based machines.  Only choose this option
 392          if you have one of these machines.
 393
 394config X86_UV
 395        bool "SGI Ultraviolet"
 396        depends on X86_64
 397        depends on X86_EXTENDED_PLATFORM
 398        depends on NUMA
 399        depends on X86_X2APIC
 400        ---help---
 401          This option is needed in order to support SGI Ultraviolet systems.
 402          If you don't have one of these, you should say N here.
 403
 404# Following is an alphabetically sorted list of 32 bit extended platforms
 405# Please maintain the alphabetic order if and when there are additions
 406
 407config X86_INTEL_CE
 408        bool "CE4100 TV platform"
 409        depends on PCI
 410        depends on PCI_GODIRECT
 411        depends on X86_32
 412        depends on X86_EXTENDED_PLATFORM
 413        select X86_REBOOTFIXUPS
 414        select OF
 415        select OF_EARLY_FLATTREE
 416        select IRQ_DOMAIN
 417        ---help---
 418          Select for the Intel CE media processor (CE4100) SOC.
 419          This option compiles in support for the CE4100 SOC for settop
 420          boxes and media devices.
 421
 422config X86_WANT_INTEL_MID
 423        bool "Intel MID platform support"
 424        depends on X86_32
 425        depends on X86_EXTENDED_PLATFORM
 426        ---help---
 427          Select to build a kernel capable of supporting Intel MID platform
 428          systems which do not have the PCI legacy interfaces (Moorestown,
 429          Medfield). If you are building for a PC class system say N here.
 430
 431if X86_WANT_INTEL_MID
 432
 433config X86_INTEL_MID
 434        bool
 435
 436config X86_MDFLD
 437       bool "Medfield MID platform"
 438        depends on PCI
 439        depends on PCI_GOANY
 440        depends on X86_IO_APIC
 441        select X86_INTEL_MID
 442        select SFI
 443        select DW_APB_TIMER
 444        select APB_TIMER
 445        select I2C
 446        select SPI
 447        select INTEL_SCU_IPC
 448        select X86_PLATFORM_DEVICES
 449        select MFD_INTEL_MSIC
 450        ---help---
 451          Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin
 452          Internet Device(MID) platform. 
 453          Unlike standard x86 PCs, Medfield does not have many legacy devices
 454          nor standard legacy replacement devices/features. e.g. Medfield does
 455          not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
 456
 457endif
 458
 459config X86_RDC321X
 460        bool "RDC R-321x SoC"
 461        depends on X86_32
 462        depends on X86_EXTENDED_PLATFORM
 463        select M486
 464        select X86_REBOOTFIXUPS
 465        ---help---
 466          This option is needed for RDC R-321x system-on-chip, also known
 467          as R-8610-(G).
 468          If you don't have one of these chips, you should say N here.
 469
 470config X86_32_NON_STANDARD
 471        bool "Support non-standard 32-bit SMP architectures"
 472        depends on X86_32 && SMP
 473        depends on X86_EXTENDED_PLATFORM
 474        ---help---
 475          This option compiles in the NUMAQ, Summit, bigsmp, ES7000,
 476          STA2X11, default subarchitectures.  It is intended for a generic
 477          binary kernel. If you select them all, kernel will probe it
 478          one by one and will fallback to default.
 479
 480# Alphabetically sorted list of Non standard 32 bit platforms
 481
 482config X86_NUMAQ
 483        bool "NUMAQ (IBM/Sequent)"
 484        depends on X86_32_NON_STANDARD
 485        depends on PCI
 486        select NUMA
 487        select X86_MPPARSE
 488        ---help---
 489          This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
 490          NUMA multiquad box. This changes the way that processors are
 491          bootstrapped, and uses Clustered Logical APIC addressing mode instead
 492          of Flat Logical.  You will need a new lynxer.elf file to flash your
 493          firmware with - send email to <Martin.Bligh@us.ibm.com>.
 494
 495config X86_SUPPORTS_MEMORY_FAILURE
 496        def_bool y
 497        # MCE code calls memory_failure():
 498        depends on X86_MCE
 499        # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
 500        depends on !X86_NUMAQ
 501        # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
 502        depends on X86_64 || !SPARSEMEM
 503        select ARCH_SUPPORTS_MEMORY_FAILURE
 504
 505config X86_VISWS
 506        bool "SGI 320/540 (Visual Workstation)"
 507        depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
 508        depends on X86_32_NON_STANDARD
 509        ---help---
 510          The SGI Visual Workstation series is an IA32-based workstation
 511          based on SGI systems chips with some legacy PC hardware attached.
 512
 513          Say Y here to create a kernel to run on the SGI 320 or 540.
 514
 515          A kernel compiled for the Visual Workstation will run on general
 516          PCs as well. See <file:Documentation/sgi-visws.txt> for details.
 517
 518config STA2X11
 519        bool "STA2X11 Companion Chip Support"
 520        depends on X86_32_NON_STANDARD && PCI
 521        select X86_DEV_DMA_OPS
 522        select X86_DMA_REMAP
 523        select SWIOTLB
 524        select MFD_STA2X11
 525        select ARCH_REQUIRE_GPIOLIB
 526        default n
 527        ---help---
 528          This adds support for boards based on the STA2X11 IO-Hub,
 529          a.k.a. "ConneXt". The chip is used in place of the standard
 530          PC chipset, so all "standard" peripherals are missing. If this
 531          option is selected the kernel will still be able to boot on
 532          standard PC machines.
 533
 534config X86_SUMMIT
 535        bool "Summit/EXA (IBM x440)"
 536        depends on X86_32_NON_STANDARD
 537        ---help---
 538          This option is needed for IBM systems that use the Summit/EXA chipset.
 539          In particular, it is needed for the x440.
 540
 541config X86_ES7000
 542        bool "Unisys ES7000 IA32 series"
 543        depends on X86_32_NON_STANDARD && X86_BIGSMP
 544        ---help---
 545          Support for Unisys ES7000 systems.  Say 'Y' here if this kernel is
 546          supposed to run on an IA32-based Unisys ES7000 system.
 547
 548config X86_32_IRIS
 549        tristate "Eurobraille/Iris poweroff module"
 550        depends on X86_32
 551        ---help---
 552          The Iris machines from EuroBraille do not have APM or ACPI support
 553          to shut themselves down properly.  A special I/O sequence is
 554          needed to do so, which is what this module does at
 555          kernel shutdown.
 556
 557          This is only for Iris machines from EuroBraille.
 558
 559          If unused, say N.
 560
 561config SCHED_OMIT_FRAME_POINTER
 562        def_bool y
 563        prompt "Single-depth WCHAN output"
 564        depends on X86
 565        ---help---
 566          Calculate simpler /proc/<PID>/wchan values. If this option
 567          is disabled then wchan values will recurse back to the
 568          caller function. This provides more accurate wchan values,
 569          at the expense of slightly more scheduling overhead.
 570
 571          If in doubt, say "Y".
 572
 573menuconfig PARAVIRT_GUEST
 574        bool "Paravirtualized guest support"
 575        ---help---
 576          Say Y here to get to see options related to running Linux under
 577          various hypervisors.  This option alone does not add any kernel code.
 578
 579          If you say N, all options in this submenu will be skipped and disabled.
 580
 581if PARAVIRT_GUEST
 582
 583config PARAVIRT_TIME_ACCOUNTING
 584        bool "Paravirtual steal time accounting"
 585        select PARAVIRT
 586        default n
 587        ---help---
 588          Select this option to enable fine granularity task steal time
 589          accounting. Time spent executing other tasks in parallel with
 590          the current vCPU is discounted from the vCPU power. To account for
 591          that, there can be a small performance impact.
 592
 593          If in doubt, say N here.
 594
 595source "arch/x86/xen/Kconfig"
 596
 597config KVM_GUEST
 598        bool "KVM Guest support (including kvmclock)"
 599        select PARAVIRT
 600        select PARAVIRT
 601        select PARAVIRT_CLOCK
 602        default y if PARAVIRT_GUEST
 603        ---help---
 604          This option enables various optimizations for running under the KVM
 605          hypervisor. It includes a paravirtualized clock, so that instead
 606          of relying on a PIT (or probably other) emulation by the
 607          underlying device model, the host provides the guest with
 608          timing infrastructure such as time of day, and system time
 609
 610source "arch/x86/lguest/Kconfig"
 611
 612config PARAVIRT
 613        bool "Enable paravirtualization code"
 614        ---help---
 615          This changes the kernel so it can modify itself when it is run
 616          under a hypervisor, potentially improving performance significantly
 617          over full virtualization.  However, when run without a hypervisor
 618          the kernel is theoretically slower and slightly larger.
 619
 620config PARAVIRT_SPINLOCKS
 621        bool "Paravirtualization layer for spinlocks"
 622        depends on PARAVIRT && SMP && EXPERIMENTAL
 623        ---help---
 624          Paravirtualized spinlocks allow a pvops backend to replace the
 625          spinlock implementation with something virtualization-friendly
 626          (for example, block the virtual CPU rather than spinning).
 627
 628          Unfortunately the downside is an up to 5% performance hit on
 629          native kernels, with various workloads.
 630
 631          If you are unsure how to answer this question, answer N.
 632
 633config PARAVIRT_CLOCK
 634        bool
 635
 636endif
 637
 638config PARAVIRT_DEBUG
 639        bool "paravirt-ops debugging"
 640        depends on PARAVIRT && DEBUG_KERNEL
 641        ---help---
 642          Enable to debug paravirt_ops internals.  Specifically, BUG if
 643          a paravirt_op is missing when it is called.
 644
 645config NO_BOOTMEM
 646        def_bool y
 647
 648config MEMTEST
 649        bool "Memtest"
 650        ---help---
 651          This option adds a kernel parameter 'memtest', which allows memtest
 652          to be set.
 653                memtest=0, mean disabled; -- default
 654                memtest=1, mean do 1 test pattern;
 655                ...
 656                memtest=4, mean do 4 test patterns.
 657          If you are unsure how to answer this question, answer N.
 658
 659config X86_SUMMIT_NUMA
 660        def_bool y
 661        depends on X86_32 && NUMA && X86_32_NON_STANDARD
 662
 663config X86_CYCLONE_TIMER
 664        def_bool y
 665        depends on X86_SUMMIT
 666
 667source "arch/x86/Kconfig.cpu"
 668
 669config HPET_TIMER
 670        def_bool X86_64
 671        prompt "HPET Timer Support" if X86_32
 672        ---help---
 673          Use the IA-PC HPET (High Precision Event Timer) to manage
 674          time in preference to the PIT and RTC, if a HPET is
 675          present.
 676          HPET is the next generation timer replacing legacy 8254s.
 677          The HPET provides a stable time base on SMP
 678          systems, unlike the TSC, but it is more expensive to access,
 679          as it is off-chip.  You can find the HPET spec at
 680          <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
 681
 682          You can safely choose Y here.  However, HPET will only be
 683          activated if the platform and the BIOS support this feature.
 684          Otherwise the 8254 will be used for timing services.
 685
 686          Choose N to continue using the legacy 8254 timer.
 687
 688config HPET_EMULATE_RTC
 689        def_bool y
 690        depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
 691
 692config APB_TIMER
 693       def_bool y if X86_INTEL_MID
 694       prompt "Intel MID APB Timer Support" if X86_INTEL_MID
 695       select DW_APB_TIMER
 696       depends on X86_INTEL_MID && SFI
 697       help
 698         APB timer is the replacement for 8254, HPET on X86 MID platforms.
 699         The APBT provides a stable time base on SMP
 700         systems, unlike the TSC, but it is more expensive to access,
 701         as it is off-chip. APB timers are always running regardless of CPU
 702         C states, they are used as per CPU clockevent device when possible.
 703
 704# Mark as expert because too many people got it wrong.
 705# The code disables itself when not needed.
 706config DMI
 707        default y
 708        bool "Enable DMI scanning" if EXPERT
 709        ---help---
 710          Enabled scanning of DMI to identify machine quirks. Say Y
 711          here unless you have verified that your setup is not
 712          affected by entries in the DMI blacklist. Required by PNP
 713          BIOS code.
 714
 715config GART_IOMMU
 716        bool "GART IOMMU support" if EXPERT
 717        default y
 718        select SWIOTLB
 719        depends on X86_64 && PCI && AMD_NB
 720        ---help---
 721          Support for full DMA access of devices with 32bit memory access only
 722          on systems with more than 3GB. This is usually needed for USB,
 723          sound, many IDE/SATA chipsets and some other devices.
 724          Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
 725          based hardware IOMMU and a software bounce buffer based IOMMU used
 726          on Intel systems and as fallback.
 727          The code is only active when needed (enough memory and limited
 728          device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
 729          too.
 730
 731config CALGARY_IOMMU
 732        bool "IBM Calgary IOMMU support"
 733        select SWIOTLB
 734        depends on X86_64 && PCI && EXPERIMENTAL
 735        ---help---
 736          Support for hardware IOMMUs in IBM's xSeries x366 and x460
 737          systems. Needed to run systems with more than 3GB of memory
 738          properly with 32-bit PCI devices that do not support DAC
 739          (Double Address Cycle). Calgary also supports bus level
 740          isolation, where all DMAs pass through the IOMMU.  This
 741          prevents them from going anywhere except their intended
 742          destination. This catches hard-to-find kernel bugs and
 743          mis-behaving drivers and devices that do not use the DMA-API
 744          properly to set up their DMA buffers.  The IOMMU can be
 745          turned off at boot time with the iommu=off parameter.
 746          Normally the kernel will make the right choice by itself.
 747          If unsure, say Y.
 748
 749config CALGARY_IOMMU_ENABLED_BY_DEFAULT
 750        def_bool y
 751        prompt "Should Calgary be enabled by default?"
 752        depends on CALGARY_IOMMU
 753        ---help---
 754          Should Calgary be enabled by default? if you choose 'y', Calgary
 755          will be used (if it exists). If you choose 'n', Calgary will not be
 756          used even if it exists. If you choose 'n' and would like to use
 757          Calgary anyway, pass 'iommu=calgary' on the kernel command line.
 758          If unsure, say Y.
 759
 760# need this always selected by IOMMU for the VIA workaround
 761config SWIOTLB
 762        def_bool y if X86_64
 763        ---help---
 764          Support for software bounce buffers used on x86-64 systems
 765          which don't have a hardware IOMMU. Using this PCI devices
 766          which can only access 32-bits of memory can be used on systems
 767          with more than 3 GB of memory.
 768          If unsure, say Y.
 769
 770config IOMMU_HELPER
 771        def_bool y
 772        depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
 773
 774config MAXSMP
 775        bool "Enable Maximum number of SMP Processors and NUMA Nodes"
 776        depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
 777        select CPUMASK_OFFSTACK
 778        ---help---
 779          Enable maximum number of CPUS and NUMA Nodes for this architecture.
 780          If unsure, say N.
 781
 782config NR_CPUS
 783        int "Maximum number of CPUs" if SMP && !MAXSMP
 784        range 2 8 if SMP && X86_32 && !X86_BIGSMP
 785        range 2 512 if SMP && !MAXSMP
 786        default "1" if !SMP
 787        default "4096" if MAXSMP
 788        default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
 789        default "8" if SMP
 790        ---help---
 791          This allows you to specify the maximum number of CPUs which this
 792          kernel will support.  The maximum supported value is 512 and the
 793          minimum value which makes sense is 2.
 794
 795          This is purely to save memory - each supported CPU adds
 796          approximately eight kilobytes to the kernel image.
 797
 798config SCHED_SMT
 799        bool "SMT (Hyperthreading) scheduler support"
 800        depends on X86_HT
 801        ---help---
 802          SMT scheduler support improves the CPU scheduler's decision making
 803          when dealing with Intel Pentium 4 chips with HyperThreading at a
 804          cost of slightly increased overhead in some places. If unsure say
 805          N here.
 806
 807config SCHED_MC
 808        def_bool y
 809        prompt "Multi-core scheduler support"
 810        depends on X86_HT
 811        ---help---
 812          Multi-core scheduler support improves the CPU scheduler's decision
 813          making when dealing with multi-core CPU chips at a cost of slightly
 814          increased overhead in some places. If unsure say N here.
 815
 816source "kernel/Kconfig.preempt"
 817
 818config X86_UP_APIC
 819        bool "Local APIC support on uniprocessors"
 820        depends on X86_32 && !SMP && !X86_32_NON_STANDARD
 821        ---help---
 822          A local APIC (Advanced Programmable Interrupt Controller) is an
 823          integrated interrupt controller in the CPU. If you have a single-CPU
 824          system which has a processor with a local APIC, you can say Y here to
 825          enable and use it. If you say Y here even though your machine doesn't
 826          have a local APIC, then the kernel will still run with no slowdown at
 827          all. The local APIC supports CPU-generated self-interrupts (timer,
 828          performance counters), and the NMI watchdog which detects hard
 829          lockups.
 830
 831config X86_UP_IOAPIC
 832        bool "IO-APIC support on uniprocessors"
 833        depends on X86_UP_APIC
 834        ---help---
 835          An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
 836          SMP-capable replacement for PC-style interrupt controllers. Most
 837          SMP systems and many recent uniprocessor systems have one.
 838
 839          If you have a single-CPU system with an IO-APIC, you can say Y here
 840          to use it. If you say Y here even though your machine doesn't have
 841          an IO-APIC, then the kernel will still run with no slowdown at all.
 842
 843config X86_LOCAL_APIC
 844        def_bool y
 845        depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
 846
 847config X86_IO_APIC
 848        def_bool y
 849        depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC
 850
 851config X86_VISWS_APIC
 852        def_bool y
 853        depends on X86_32 && X86_VISWS
 854
 855config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
 856        bool "Reroute for broken boot IRQs"
 857        depends on X86_IO_APIC
 858        ---help---
 859          This option enables a workaround that fixes a source of
 860          spurious interrupts. This is recommended when threaded
 861          interrupt handling is used on systems where the generation of
 862          superfluous "boot interrupts" cannot be disabled.
 863
 864          Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
 865          entry in the chipset's IO-APIC is masked (as, e.g. the RT
 866          kernel does during interrupt handling). On chipsets where this
 867          boot IRQ generation cannot be disabled, this workaround keeps
 868          the original IRQ line masked so that only the equivalent "boot
 869          IRQ" is delivered to the CPUs. The workaround also tells the
 870          kernel to set up the IRQ handler on the boot IRQ line. In this
 871          way only one interrupt is delivered to the kernel. Otherwise
 872          the spurious second interrupt may cause the kernel to bring
 873          down (vital) interrupt lines.
 874
 875          Only affects "broken" chipsets. Interrupt sharing may be
 876          increased on these systems.
 877
 878config X86_MCE
 879        bool "Machine Check / overheating reporting"
 880        default y
 881        ---help---
 882          Machine Check support allows the processor to notify the
 883          kernel if it detects a problem (e.g. overheating, data corruption).
 884          The action the kernel takes depends on the severity of the problem,
 885          ranging from warning messages to halting the machine.
 886
 887config X86_MCE_INTEL
 888        def_bool y
 889        prompt "Intel MCE features"
 890        depends on X86_MCE && X86_LOCAL_APIC
 891        ---help---
 892           Additional support for intel specific MCE features such as
 893           the thermal monitor.
 894
 895config X86_MCE_AMD
 896        def_bool y
 897        prompt "AMD MCE features"
 898        depends on X86_MCE && X86_LOCAL_APIC
 899        ---help---
 900           Additional support for AMD specific MCE features such as
 901           the DRAM Error Threshold.
 902
 903config X86_ANCIENT_MCE
 904        bool "Support for old Pentium 5 / WinChip machine checks"
 905        depends on X86_32 && X86_MCE
 906        ---help---
 907          Include support for machine check handling on old Pentium 5 or WinChip
 908          systems. These typically need to be enabled explicitely on the command
 909          line.
 910
 911config X86_MCE_THRESHOLD
 912        depends on X86_MCE_AMD || X86_MCE_INTEL
 913        def_bool y
 914
 915config X86_MCE_INJECT
 916        depends on X86_MCE
 917        tristate "Machine check injector support"
 918        ---help---
 919          Provide support for injecting machine checks for testing purposes.
 920          If you don't know what a machine check is and you don't do kernel
 921          QA it is safe to say n.
 922
 923config X86_THERMAL_VECTOR
 924        def_bool y
 925        depends on X86_MCE_INTEL
 926
 927config VM86
 928        bool "Enable VM86 support" if EXPERT
 929        default y
 930        depends on X86_32
 931        ---help---
 932          This option is required by programs like DOSEMU to run 16-bit legacy
 933          code on X86 processors. It also may be needed by software like
 934          XFree86 to initialize some video cards via BIOS. Disabling this
 935          option saves about 6k.
 936
 937config TOSHIBA
 938        tristate "Toshiba Laptop support"
 939        depends on X86_32
 940        ---help---
 941          This adds a driver to safely access the System Management Mode of
 942          the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
 943          not work on models with a Phoenix BIOS. The System Management Mode
 944          is used to set the BIOS and power saving options on Toshiba portables.
 945
 946          For information on utilities to make use of this driver see the
 947          Toshiba Linux utilities web site at:
 948          <http://www.buzzard.org.uk/toshiba/>.
 949
 950          Say Y if you intend to run this kernel on a Toshiba portable.
 951          Say N otherwise.
 952
 953config I8K
 954        tristate "Dell laptop support"
 955        select HWMON
 956        ---help---
 957          This adds a driver to safely access the System Management Mode
 958          of the CPU on the Dell Inspiron 8000. The System Management Mode
 959          is used to read cpu temperature and cooling fan status and to
 960          control the fans on the I8K portables.
 961
 962          This driver has been tested only on the Inspiron 8000 but it may
 963          also work with other Dell laptops. You can force loading on other
 964          models by passing the parameter `force=1' to the module. Use at
 965          your own risk.
 966
 967          For information on utilities to make use of this driver see the
 968          I8K Linux utilities web site at:
 969          <http://people.debian.org/~dz/i8k/>
 970
 971          Say Y if you intend to run this kernel on a Dell Inspiron 8000.
 972          Say N otherwise.
 973
 974config X86_REBOOTFIXUPS
 975        bool "Enable X86 board specific fixups for reboot"
 976        depends on X86_32
 977        ---help---
 978          This enables chipset and/or board specific fixups to be done
 979          in order to get reboot to work correctly. This is only needed on
 980          some combinations of hardware and BIOS. The symptom, for which
 981          this config is intended, is when reboot ends with a stalled/hung
 982          system.
 983
 984          Currently, the only fixup is for the Geode machines using
 985          CS5530A and CS5536 chipsets and the RDC R-321x SoC.
 986
 987          Say Y if you want to enable the fixup. Currently, it's safe to
 988          enable this option even if you don't need it.
 989          Say N otherwise.
 990
 991config MICROCODE
 992        tristate "CPU microcode loading support"
 993        select FW_LOADER
 994        ---help---
 995
 996          If you say Y here, you will be able to update the microcode on
 997          certain Intel and AMD processors. The Intel support is for the
 998          IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
 999          Xeon etc. The AMD support is for families 0x10 and later. You will
1000          obviously need the actual microcode binary data itself which is not
1001          shipped with the Linux kernel.
1002
1003          This option selects the general module only, you need to select
1004          at least one vendor specific module as well.
1005
1006          To compile this driver as a module, choose M here: the module
1007          will be called microcode.
1008
1009config MICROCODE_INTEL
1010        bool "Intel microcode loading support"
1011        depends on MICROCODE
1012        default MICROCODE
1013        select FW_LOADER
1014        ---help---
1015          This options enables microcode patch loading support for Intel
1016          processors.
1017
1018          For latest news and information on obtaining all the required
1019          Intel ingredients for this driver, check:
1020          <http://www.urbanmyth.org/microcode/>.
1021
1022config MICROCODE_AMD
1023        bool "AMD microcode loading support"
1024        depends on MICROCODE
1025        select FW_LOADER
1026        ---help---
1027          If you select this option, microcode patch loading support for AMD
1028          processors will be enabled.
1029
1030config MICROCODE_OLD_INTERFACE
1031        def_bool y
1032        depends on MICROCODE
1033
1034config X86_MSR
1035        tristate "/dev/cpu/*/msr - Model-specific register support"
1036        ---help---
1037          This device gives privileged processes access to the x86
1038          Model-Specific Registers (MSRs).  It is a character device with
1039          major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1040          MSR accesses are directed to a specific CPU on multi-processor
1041          systems.
1042
1043config X86_CPUID
1044        tristate "/dev/cpu/*/cpuid - CPU information support"
1045        ---help---
1046          This device gives processes access to the x86 CPUID instruction to
1047          be executed on a specific processor.  It is a character device
1048          with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1049          /dev/cpu/31/cpuid.
1050
1051choice
1052        prompt "High Memory Support"
1053        default HIGHMEM64G if X86_NUMAQ
1054        default HIGHMEM4G
1055        depends on X86_32
1056
1057config NOHIGHMEM
1058        bool "off"
1059        depends on !X86_NUMAQ
1060        ---help---
1061          Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1062          However, the address space of 32-bit x86 processors is only 4
1063          Gigabytes large. That means that, if you have a large amount of
1064          physical memory, not all of it can be "permanently mapped" by the
1065          kernel. The physical memory that's not permanently mapped is called
1066          "high memory".
1067
1068          If you are compiling a kernel which will never run on a machine with
1069          more than 1 Gigabyte total physical RAM, answer "off" here (default
1070          choice and suitable for most users). This will result in a "3GB/1GB"
1071          split: 3GB are mapped so that each process sees a 3GB virtual memory
1072          space and the remaining part of the 4GB virtual memory space is used
1073          by the kernel to permanently map as much physical memory as
1074          possible.
1075
1076          If the machine has between 1 and 4 Gigabytes physical RAM, then
1077          answer "4GB" here.
1078
1079          If more than 4 Gigabytes is used then answer "64GB" here. This
1080          selection turns Intel PAE (Physical Address Extension) mode on.
1081          PAE implements 3-level paging on IA32 processors. PAE is fully
1082          supported by Linux, PAE mode is implemented on all recent Intel
1083          processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1084          then the kernel will not boot on CPUs that don't support PAE!
1085
1086          The actual amount of total physical memory will either be
1087          auto detected or can be forced by using a kernel command line option
1088          such as "mem=256M". (Try "man bootparam" or see the documentation of
1089          your boot loader (lilo or loadlin) about how to pass options to the
1090          kernel at boot time.)
1091
1092          If unsure, say "off".
1093
1094config HIGHMEM4G
1095        bool "4GB"
1096        depends on !X86_NUMAQ
1097        ---help---
1098          Select this if you have a 32-bit processor and between 1 and 4
1099          gigabytes of physical RAM.
1100
1101config HIGHMEM64G
1102        bool "64GB"
1103        depends on !M386 && !M486
1104        select X86_PAE
1105        ---help---
1106          Select this if you have a 32-bit processor and more than 4
1107          gigabytes of physical RAM.
1108
1109endchoice
1110
1111choice
1112        depends on EXPERIMENTAL
1113        prompt "Memory split" if EXPERT
1114        default VMSPLIT_3G
1115        depends on X86_32
1116        ---help---
1117          Select the desired split between kernel and user memory.
1118
1119          If the address range available to the kernel is less than the
1120          physical memory installed, the remaining memory will be available
1121          as "high memory". Accessing high memory is a little more costly
1122          than low memory, as it needs to be mapped into the kernel first.
1123          Note that increasing the kernel address space limits the range
1124          available to user programs, making the address space there
1125          tighter.  Selecting anything other than the default 3G/1G split
1126          will also likely make your kernel incompatible with binary-only
1127          kernel modules.
1128
1129          If you are not absolutely sure what you are doing, leave this
1130          option alone!
1131
1132        config VMSPLIT_3G
1133                bool "3G/1G user/kernel split"
1134        config VMSPLIT_3G_OPT
1135                depends on !X86_PAE
1136                bool "3G/1G user/kernel split (for full 1G low memory)"
1137        config VMSPLIT_2G
1138                bool "2G/2G user/kernel split"
1139        config VMSPLIT_2G_OPT
1140                depends on !X86_PAE
1141                bool "2G/2G user/kernel split (for full 2G low memory)"
1142        config VMSPLIT_1G
1143                bool "1G/3G user/kernel split"
1144endchoice
1145
1146config PAGE_OFFSET
1147        hex
1148        default 0xB0000000 if VMSPLIT_3G_OPT
1149        default 0x80000000 if VMSPLIT_2G
1150        default 0x78000000 if VMSPLIT_2G_OPT
1151        default 0x40000000 if VMSPLIT_1G
1152        default 0xC0000000
1153        depends on X86_32
1154
1155config HIGHMEM
1156        def_bool y
1157        depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1158
1159config X86_PAE
1160        bool "PAE (Physical Address Extension) Support"
1161        depends on X86_32 && !HIGHMEM4G
1162        ---help---
1163          PAE is required for NX support, and furthermore enables
1164          larger swapspace support for non-overcommit purposes. It
1165          has the cost of more pagetable lookup overhead, and also
1166          consumes more pagetable space per process.
1167
1168config ARCH_PHYS_ADDR_T_64BIT
1169        def_bool y
1170        depends on X86_64 || X86_PAE
1171
1172config ARCH_DMA_ADDR_T_64BIT
1173        def_bool y
1174        depends on X86_64 || HIGHMEM64G
1175
1176config DIRECT_GBPAGES
1177        bool "Enable 1GB pages for kernel pagetables" if EXPERT
1178        default y
1179        depends on X86_64
1180        ---help---
1181          Allow the kernel linear mapping to use 1GB pages on CPUs that
1182          support it. This can improve the kernel's performance a tiny bit by
1183          reducing TLB pressure. If in doubt, say "Y".
1184
1185# Common NUMA Features
1186config NUMA
1187        bool "Numa Memory Allocation and Scheduler Support"
1188        depends on SMP
1189        depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1190        default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1191        ---help---
1192          Enable NUMA (Non Uniform Memory Access) support.
1193
1194          The kernel will try to allocate memory used by a CPU on the
1195          local memory controller of the CPU and add some more
1196          NUMA awareness to the kernel.
1197
1198          For 64-bit this is recommended if the system is Intel Core i7
1199          (or later), AMD Opteron, or EM64T NUMA.
1200
1201          For 32-bit this is only needed on (rare) 32-bit-only platforms
1202          that support NUMA topologies, such as NUMAQ / Summit, or if you
1203          boot a 32-bit kernel on a 64-bit NUMA platform.
1204
1205          Otherwise, you should say N.
1206
1207comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1208        depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1209
1210config AMD_NUMA
1211        def_bool y
1212        prompt "Old style AMD Opteron NUMA detection"
1213        depends on X86_64 && NUMA && PCI
1214        ---help---
1215          Enable AMD NUMA node topology detection.  You should say Y here if
1216          you have a multi processor AMD system. This uses an old method to
1217          read the NUMA configuration directly from the builtin Northbridge
1218          of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1219          which also takes priority if both are compiled in.
1220
1221config X86_64_ACPI_NUMA
1222        def_bool y
1223        prompt "ACPI NUMA detection"
1224        depends on X86_64 && NUMA && ACPI && PCI
1225        select ACPI_NUMA
1226        ---help---
1227          Enable ACPI SRAT based node topology detection.
1228
1229# Some NUMA nodes have memory ranges that span
1230# other nodes.  Even though a pfn is valid and
1231# between a node's start and end pfns, it may not
1232# reside on that node.  See memmap_init_zone()
1233# for details.
1234config NODES_SPAN_OTHER_NODES
1235        def_bool y
1236        depends on X86_64_ACPI_NUMA
1237
1238config NUMA_EMU
1239        bool "NUMA emulation"
1240        depends on NUMA
1241        ---help---
1242          Enable NUMA emulation. A flat machine will be split
1243          into virtual nodes when booted with "numa=fake=N", where N is the
1244          number of nodes. This is only useful for debugging.
1245
1246config NODES_SHIFT
1247        int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1248        range 1 10
1249        default "10" if MAXSMP
1250        default "6" if X86_64
1251        default "4" if X86_NUMAQ
1252        default "3"
1253        depends on NEED_MULTIPLE_NODES
1254        ---help---
1255          Specify the maximum number of NUMA Nodes available on the target
1256          system.  Increases memory reserved to accommodate various tables.
1257
1258config HAVE_ARCH_ALLOC_REMAP
1259        def_bool y
1260        depends on X86_32 && NUMA
1261
1262config ARCH_HAVE_MEMORY_PRESENT
1263        def_bool y
1264        depends on X86_32 && DISCONTIGMEM
1265
1266config NEED_NODE_MEMMAP_SIZE
1267        def_bool y
1268        depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1269
1270config ARCH_FLATMEM_ENABLE
1271        def_bool y
1272        depends on X86_32 && !NUMA
1273
1274config ARCH_DISCONTIGMEM_ENABLE
1275        def_bool y
1276        depends on NUMA && X86_32
1277
1278config ARCH_DISCONTIGMEM_DEFAULT
1279        def_bool y
1280        depends on NUMA && X86_32
1281
1282config ARCH_SPARSEMEM_ENABLE
1283        def_bool y
1284        depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1285        select SPARSEMEM_STATIC if X86_32
1286        select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1287
1288config ARCH_SPARSEMEM_DEFAULT
1289        def_bool y
1290        depends on X86_64
1291
1292config ARCH_SELECT_MEMORY_MODEL
1293        def_bool y
1294        depends on ARCH_SPARSEMEM_ENABLE
1295
1296config ARCH_MEMORY_PROBE
1297        def_bool y
1298        depends on X86_64 && MEMORY_HOTPLUG
1299
1300config ARCH_PROC_KCORE_TEXT
1301        def_bool y
1302        depends on X86_64 && PROC_KCORE
1303
1304config ILLEGAL_POINTER_VALUE
1305       hex
1306       default 0 if X86_32
1307       default 0xdead000000000000 if X86_64
1308
1309source "mm/Kconfig"
1310
1311config HIGHPTE
1312        bool "Allocate 3rd-level pagetables from highmem"
1313        depends on HIGHMEM
1314        ---help---
1315          The VM uses one page table entry for each page of physical memory.
1316          For systems with a lot of RAM, this can be wasteful of precious
1317          low memory.  Setting this option will put user-space page table
1318          entries in high memory.
1319
1320config X86_CHECK_BIOS_CORRUPTION
1321        bool "Check for low memory corruption"
1322        ---help---
1323          Periodically check for memory corruption in low memory, which
1324          is suspected to be caused by BIOS.  Even when enabled in the
1325          configuration, it is disabled at runtime.  Enable it by
1326          setting "memory_corruption_check=1" on the kernel command
1327          line.  By default it scans the low 64k of memory every 60
1328          seconds; see the memory_corruption_check_size and
1329          memory_corruption_check_period parameters in
1330          Documentation/kernel-parameters.txt to adjust this.
1331
1332          When enabled with the default parameters, this option has
1333          almost no overhead, as it reserves a relatively small amount
1334          of memory and scans it infrequently.  It both detects corruption
1335          and prevents it from affecting the running system.
1336
1337          It is, however, intended as a diagnostic tool; if repeatable
1338          BIOS-originated corruption always affects the same memory,
1339          you can use memmap= to prevent the kernel from using that
1340          memory.
1341
1342config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1343        bool "Set the default setting of memory_corruption_check"
1344        depends on X86_CHECK_BIOS_CORRUPTION
1345        default y
1346        ---help---
1347          Set whether the default state of memory_corruption_check is
1348          on or off.
1349
1350config X86_RESERVE_LOW
1351        int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1352        default 64
1353        range 4 640
1354        ---help---
1355          Specify the amount of low memory to reserve for the BIOS.
1356
1357          The first page contains BIOS data structures that the kernel
1358          must not use, so that page must always be reserved.
1359
1360          By default we reserve the first 64K of physical RAM, as a
1361          number of BIOSes are known to corrupt that memory range
1362          during events such as suspend/resume or monitor cable
1363          insertion, so it must not be used by the kernel.
1364
1365          You can set this to 4 if you are absolutely sure that you
1366          trust the BIOS to get all its memory reservations and usages
1367          right.  If you know your BIOS have problems beyond the
1368          default 64K area, you can set this to 640 to avoid using the
1369          entire low memory range.
1370
1371          If you have doubts about the BIOS (e.g. suspend/resume does
1372          not work or there's kernel crashes after certain hardware
1373          hotplug events) then you might want to enable
1374          X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1375          typical corruption patterns.
1376
1377          Leave this to the default value of 64 if you are unsure.
1378
1379config MATH_EMULATION
1380        bool
1381        prompt "Math emulation" if X86_32
1382        ---help---
1383          Linux can emulate a math coprocessor (used for floating point
1384          operations) if you don't have one. 486DX and Pentium processors have
1385          a math coprocessor built in, 486SX and 386 do not, unless you added
1386          a 487DX or 387, respectively. (The messages during boot time can
1387          give you some hints here ["man dmesg"].) Everyone needs either a
1388          coprocessor or this emulation.
1389
1390          If you don't have a math coprocessor, you need to say Y here; if you
1391          say Y here even though you have a coprocessor, the coprocessor will
1392          be used nevertheless. (This behavior can be changed with the kernel
1393          command line option "no387", which comes handy if your coprocessor
1394          is broken. Try "man bootparam" or see the documentation of your boot
1395          loader (lilo or loadlin) about how to pass options to the kernel at
1396          boot time.) This means that it is a good idea to say Y here if you
1397          intend to use this kernel on different machines.
1398
1399          More information about the internals of the Linux math coprocessor
1400          emulation can be found in <file:arch/x86/math-emu/README>.
1401
1402          If you are not sure, say Y; apart from resulting in a 66 KB bigger
1403          kernel, it won't hurt.
1404
1405config MTRR
1406        def_bool y
1407        prompt "MTRR (Memory Type Range Register) support" if EXPERT
1408        ---help---
1409          On Intel P6 family processors (Pentium Pro, Pentium II and later)
1410          the Memory Type Range Registers (MTRRs) may be used to control
1411          processor access to memory ranges. This is most useful if you have
1412          a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1413          allows bus write transfers to be combined into a larger transfer
1414          before bursting over the PCI/AGP bus. This can increase performance
1415          of image write operations 2.5 times or more. Saying Y here creates a
1416          /proc/mtrr file which may be used to manipulate your processor's
1417          MTRRs. Typically the X server should use this.
1418
1419          This code has a reasonably generic interface so that similar
1420          control registers on other processors can be easily supported
1421          as well:
1422
1423          The Cyrix 6x86, 6x86MX and M II processors have Address Range
1424          Registers (ARRs) which provide a similar functionality to MTRRs. For
1425          these, the ARRs are used to emulate the MTRRs.
1426          The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1427          MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1428          write-combining. All of these processors are supported by this code
1429          and it makes sense to say Y here if you have one of them.
1430
1431          Saying Y here also fixes a problem with buggy SMP BIOSes which only
1432          set the MTRRs for the boot CPU and not for the secondary CPUs. This
1433          can lead to all sorts of problems, so it's good to say Y here.
1434
1435          You can safely say Y even if your machine doesn't have MTRRs, you'll
1436          just add about 9 KB to your kernel.
1437
1438          See <file:Documentation/x86/mtrr.txt> for more information.
1439
1440config MTRR_SANITIZER
1441        def_bool y
1442        prompt "MTRR cleanup support"
1443        depends on MTRR
1444        ---help---
1445          Convert MTRR layout from continuous to discrete, so X drivers can
1446          add writeback entries.
1447
1448          Can be disabled with disable_mtrr_cleanup on the kernel command line.
1449          The largest mtrr entry size for a continuous block can be set with
1450          mtrr_chunk_size.
1451
1452          If unsure, say Y.
1453
1454config MTRR_SANITIZER_ENABLE_DEFAULT
1455        int "MTRR cleanup enable value (0-1)"
1456        range 0 1
1457        default "0"
1458        depends on MTRR_SANITIZER
1459        ---help---
1460          Enable mtrr cleanup default value
1461
1462config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1463        int "MTRR cleanup spare reg num (0-7)"
1464        range 0 7
1465        default "1"
1466        depends on MTRR_SANITIZER
1467        ---help---
1468          mtrr cleanup spare entries default, it can be changed via
1469          mtrr_spare_reg_nr=N on the kernel command line.
1470
1471config X86_PAT
1472        def_bool y
1473        prompt "x86 PAT support" if EXPERT
1474        depends on MTRR
1475        ---help---
1476          Use PAT attributes to setup page level cache control.
1477
1478          PATs are the modern equivalents of MTRRs and are much more
1479          flexible than MTRRs.
1480
1481          Say N here if you see bootup problems (boot crash, boot hang,
1482          spontaneous reboots) or a non-working video driver.
1483
1484          If unsure, say Y.
1485
1486config ARCH_USES_PG_UNCACHED
1487        def_bool y
1488        depends on X86_PAT
1489
1490config ARCH_RANDOM
1491        def_bool y
1492        prompt "x86 architectural random number generator" if EXPERT
1493        ---help---
1494          Enable the x86 architectural RDRAND instruction
1495          (Intel Bull Mountain technology) to generate random numbers.
1496          If supported, this is a high bandwidth, cryptographically
1497          secure hardware random number generator.
1498
1499config X86_SMAP
1500        def_bool y
1501        prompt "Supervisor Mode Access Prevention" if EXPERT
1502        ---help---
1503          Supervisor Mode Access Prevention (SMAP) is a security
1504          feature in newer Intel processors.  There is a small
1505          performance cost if this enabled and turned on; there is
1506          also a small increase in the kernel size if this is enabled.
1507
1508          If unsure, say Y.
1509
1510config EFI
1511        bool "EFI runtime service support"
1512        depends on ACPI
1513        ---help---
1514          This enables the kernel to use EFI runtime services that are
1515          available (such as the EFI variable services).
1516
1517          This option is only useful on systems that have EFI firmware.
1518          In addition, you should use the latest ELILO loader available
1519          at <http://elilo.sourceforge.net> in order to take advantage
1520          of EFI runtime services. However, even with this option, the
1521          resultant kernel should continue to boot on existing non-EFI
1522          platforms.
1523
1524config EFI_STUB
1525       bool "EFI stub support"
1526       depends on EFI
1527       ---help---
1528          This kernel feature allows a bzImage to be loaded directly
1529          by EFI firmware without the use of a bootloader.
1530
1531          See Documentation/x86/efi-stub.txt for more information.
1532
1533config SECCOMP
1534        def_bool y
1535        prompt "Enable seccomp to safely compute untrusted bytecode"
1536        ---help---
1537          This kernel feature is useful for number crunching applications
1538          that may need to compute untrusted bytecode during their
1539          execution. By using pipes or other transports made available to
1540          the process as file descriptors supporting the read/write
1541          syscalls, it's possible to isolate those applications in
1542          their own address space using seccomp. Once seccomp is
1543          enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1544          and the task is only allowed to execute a few safe syscalls
1545          defined by each seccomp mode.
1546
1547          If unsure, say Y. Only embedded should say N here.
1548
1549config CC_STACKPROTECTOR
1550        bool "Enable -fstack-protector buffer overflow detection"
1551        ---help---
1552          This option turns on the -fstack-protector GCC feature. This
1553          feature puts, at the beginning of functions, a canary value on
1554          the stack just before the return address, and validates
1555          the value just before actually returning.  Stack based buffer
1556          overflows (that need to overwrite this return address) now also
1557          overwrite the canary, which gets detected and the attack is then
1558          neutralized via a kernel panic.
1559
1560          This feature requires gcc version 4.2 or above, or a distribution
1561          gcc with the feature backported. Older versions are automatically
1562          detected and for those versions, this configuration option is
1563          ignored. (and a warning is printed during bootup)
1564
1565source kernel/Kconfig.hz
1566
1567config KEXEC
1568        bool "kexec system call"
1569        ---help---
1570          kexec is a system call that implements the ability to shutdown your
1571          current kernel, and to start another kernel.  It is like a reboot
1572          but it is independent of the system firmware.   And like a reboot
1573          you can start any kernel with it, not just Linux.
1574
1575          The name comes from the similarity to the exec system call.
1576
1577          It is an ongoing process to be certain the hardware in a machine
1578          is properly shutdown, so do not be surprised if this code does not
1579          initially work for you.  It may help to enable device hotplugging
1580          support.  As of this writing the exact hardware interface is
1581          strongly in flux, so no good recommendation can be made.
1582
1583config CRASH_DUMP
1584        bool "kernel crash dumps"
1585        depends on X86_64 || (X86_32 && HIGHMEM)
1586        ---help---
1587          Generate crash dump after being started by kexec.
1588          This should be normally only set in special crash dump kernels
1589          which are loaded in the main kernel with kexec-tools into
1590          a specially reserved region and then later executed after
1591          a crash by kdump/kexec. The crash dump kernel must be compiled
1592          to a memory address not used by the main kernel or BIOS using
1593          PHYSICAL_START, or it must be built as a relocatable image
1594          (CONFIG_RELOCATABLE=y).
1595          For more details see Documentation/kdump/kdump.txt
1596
1597config KEXEC_JUMP
1598        bool "kexec jump (EXPERIMENTAL)"
1599        depends on EXPERIMENTAL
1600        depends on KEXEC && HIBERNATION
1601        ---help---
1602          Jump between original kernel and kexeced kernel and invoke
1603          code in physical address mode via KEXEC
1604
1605config PHYSICAL_START
1606        hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1607        default "0x1000000"
1608        ---help---
1609          This gives the physical address where the kernel is loaded.
1610
1611          If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1612          bzImage will decompress itself to above physical address and
1613          run from there. Otherwise, bzImage will run from the address where
1614          it has been loaded by the boot loader and will ignore above physical
1615          address.
1616
1617          In normal kdump cases one does not have to set/change this option
1618          as now bzImage can be compiled as a completely relocatable image
1619          (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1620          address. This option is mainly useful for the folks who don't want
1621          to use a bzImage for capturing the crash dump and want to use a
1622          vmlinux instead. vmlinux is not relocatable hence a kernel needs
1623          to be specifically compiled to run from a specific memory area
1624          (normally a reserved region) and this option comes handy.
1625
1626          So if you are using bzImage for capturing the crash dump,
1627          leave the value here unchanged to 0x1000000 and set
1628          CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
1629          for capturing the crash dump change this value to start of
1630          the reserved region.  In other words, it can be set based on
1631          the "X" value as specified in the "crashkernel=YM@XM"
1632          command line boot parameter passed to the panic-ed
1633          kernel. Please take a look at Documentation/kdump/kdump.txt
1634          for more details about crash dumps.
1635
1636          Usage of bzImage for capturing the crash dump is recommended as
1637          one does not have to build two kernels. Same kernel can be used
1638          as production kernel and capture kernel. Above option should have
1639          gone away after relocatable bzImage support is introduced. But it
1640          is present because there are users out there who continue to use
1641          vmlinux for dump capture. This option should go away down the
1642          line.
1643
1644          Don't change this unless you know what you are doing.
1645
1646config RELOCATABLE
1647        bool "Build a relocatable kernel"
1648        default y
1649        ---help---
1650          This builds a kernel image that retains relocation information
1651          so it can be loaded someplace besides the default 1MB.
1652          The relocations tend to make the kernel binary about 10% larger,
1653          but are discarded at runtime.
1654
1655          One use is for the kexec on panic case where the recovery kernel
1656          must live at a different physical address than the primary
1657          kernel.
1658
1659          Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1660          it has been loaded at and the compile time physical address
1661          (CONFIG_PHYSICAL_START) is ignored.
1662
1663# Relocation on x86-32 needs some additional build support
1664config X86_NEED_RELOCS
1665        def_bool y
1666        depends on X86_32 && RELOCATABLE
1667
1668config PHYSICAL_ALIGN
1669        hex "Alignment value to which kernel should be aligned" if X86_32
1670        default "0x1000000"
1671        range 0x2000 0x1000000
1672        ---help---
1673          This value puts the alignment restrictions on physical address
1674          where kernel is loaded and run from. Kernel is compiled for an
1675          address which meets above alignment restriction.
1676
1677          If bootloader loads the kernel at a non-aligned address and
1678          CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1679          address aligned to above value and run from there.
1680
1681          If bootloader loads the kernel at a non-aligned address and
1682          CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1683          load address and decompress itself to the address it has been
1684          compiled for and run from there. The address for which kernel is
1685          compiled already meets above alignment restrictions. Hence the
1686          end result is that kernel runs from a physical address meeting
1687          above alignment restrictions.
1688
1689          Don't change this unless you know what you are doing.
1690
1691config HOTPLUG_CPU
1692        bool "Support for hot-pluggable CPUs"
1693        depends on SMP && HOTPLUG
1694        ---help---
1695          Say Y here to allow turning CPUs off and on. CPUs can be
1696          controlled through /sys/devices/system/cpu.
1697          ( Note: power management support will enable this option
1698            automatically on SMP systems. )
1699          Say N if you want to disable CPU hotplug.
1700
1701config COMPAT_VDSO
1702        def_bool y
1703        prompt "Compat VDSO support"
1704        depends on X86_32 || IA32_EMULATION
1705        ---help---
1706          Map the 32-bit VDSO to the predictable old-style address too.
1707
1708          Say N here if you are running a sufficiently recent glibc
1709          version (2.3.3 or later), to remove the high-mapped
1710          VDSO mapping and to exclusively use the randomized VDSO.
1711
1712          If unsure, say Y.
1713
1714config CMDLINE_BOOL
1715        bool "Built-in kernel command line"
1716        ---help---
1717          Allow for specifying boot arguments to the kernel at
1718          build time.  On some systems (e.g. embedded ones), it is
1719          necessary or convenient to provide some or all of the
1720          kernel boot arguments with the kernel itself (that is,
1721          to not rely on the boot loader to provide them.)
1722
1723          To compile command line arguments into the kernel,
1724          set this option to 'Y', then fill in the
1725          the boot arguments in CONFIG_CMDLINE.
1726
1727          Systems with fully functional boot loaders (i.e. non-embedded)
1728          should leave this option set to 'N'.
1729
1730config CMDLINE
1731        string "Built-in kernel command string"
1732        depends on CMDLINE_BOOL
1733        default ""
1734        ---help---
1735          Enter arguments here that should be compiled into the kernel
1736          image and used at boot time.  If the boot loader provides a
1737          command line at boot time, it is appended to this string to
1738          form the full kernel command line, when the system boots.
1739
1740          However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1741          change this behavior.
1742
1743          In most cases, the command line (whether built-in or provided
1744          by the boot loader) should specify the device for the root
1745          file system.
1746
1747config CMDLINE_OVERRIDE
1748        bool "Built-in command line overrides boot loader arguments"
1749        depends on CMDLINE_BOOL
1750        ---help---
1751          Set this option to 'Y' to have the kernel ignore the boot loader
1752          command line, and use ONLY the built-in command line.
1753
1754          This is used to work around broken boot loaders.  This should
1755          be set to 'N' under normal conditions.
1756
1757endmenu
1758
1759config ARCH_ENABLE_MEMORY_HOTPLUG
1760        def_bool y
1761        depends on X86_64 || (X86_32 && HIGHMEM)
1762
1763config ARCH_ENABLE_MEMORY_HOTREMOVE
1764        def_bool y
1765        depends on MEMORY_HOTPLUG
1766
1767config USE_PERCPU_NUMA_NODE_ID
1768        def_bool y
1769        depends on NUMA
1770
1771menu "Power management and ACPI options"
1772
1773config ARCH_HIBERNATION_HEADER
1774        def_bool y
1775        depends on X86_64 && HIBERNATION
1776
1777source "kernel/power/Kconfig"
1778
1779source "drivers/acpi/Kconfig"
1780
1781source "drivers/sfi/Kconfig"
1782
1783config X86_APM_BOOT
1784        def_bool y
1785        depends on APM
1786
1787menuconfig APM
1788        tristate "APM (Advanced Power Management) BIOS support"
1789        depends on X86_32 && PM_SLEEP
1790        ---help---
1791          APM is a BIOS specification for saving power using several different
1792          techniques. This is mostly useful for battery powered laptops with
1793          APM compliant BIOSes. If you say Y here, the system time will be
1794          reset after a RESUME operation, the /proc/apm device will provide
1795          battery status information, and user-space programs will receive
1796          notification of APM "events" (e.g. battery status change).
1797
1798          If you select "Y" here, you can disable actual use of the APM
1799          BIOS by passing the "apm=off" option to the kernel at boot time.
1800
1801          Note that the APM support is almost completely disabled for
1802          machines with more than one CPU.
1803
1804          In order to use APM, you will need supporting software. For location
1805          and more information, read <file:Documentation/power/apm-acpi.txt>
1806          and the Battery Powered Linux mini-HOWTO, available from
1807          <http://www.tldp.org/docs.html#howto>.
1808
1809          This driver does not spin down disk drives (see the hdparm(8)
1810          manpage ("man 8 hdparm") for that), and it doesn't turn off
1811          VESA-compliant "green" monitors.
1812
1813          This driver does not support the TI 4000M TravelMate and the ACER
1814          486/DX4/75 because they don't have compliant BIOSes. Many "green"
1815          desktop machines also don't have compliant BIOSes, and this driver
1816          may cause those machines to panic during the boot phase.
1817
1818          Generally, if you don't have a battery in your machine, there isn't
1819          much point in using this driver and you should say N. If you get
1820          random kernel OOPSes or reboots that don't seem to be related to
1821          anything, try disabling/enabling this option (or disabling/enabling
1822          APM in your BIOS).
1823
1824          Some other things you should try when experiencing seemingly random,
1825          "weird" problems:
1826
1827          1) make sure that you have enough swap space and that it is
1828          enabled.
1829          2) pass the "no-hlt" option to the kernel
1830          3) switch on floating point emulation in the kernel and pass
1831          the "no387" option to the kernel
1832          4) pass the "floppy=nodma" option to the kernel
1833          5) pass the "mem=4M" option to the kernel (thereby disabling
1834          all but the first 4 MB of RAM)
1835          6) make sure that the CPU is not over clocked.
1836          7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1837          8) disable the cache from your BIOS settings
1838          9) install a fan for the video card or exchange video RAM
1839          10) install a better fan for the CPU
1840          11) exchange RAM chips
1841          12) exchange the motherboard.
1842
1843          To compile this driver as a module, choose M here: the
1844          module will be called apm.
1845
1846if APM
1847
1848config APM_IGNORE_USER_SUSPEND
1849        bool "Ignore USER SUSPEND"
1850        ---help---
1851          This option will ignore USER SUSPEND requests. On machines with a
1852          compliant APM BIOS, you want to say N. However, on the NEC Versa M
1853          series notebooks, it is necessary to say Y because of a BIOS bug.
1854
1855config APM_DO_ENABLE
1856        bool "Enable PM at boot time"
1857        ---help---
1858          Enable APM features at boot time. From page 36 of the APM BIOS
1859          specification: "When disabled, the APM BIOS does not automatically
1860          power manage devices, enter the Standby State, enter the Suspend
1861          State, or take power saving steps in response to CPU Idle calls."
1862          This driver will make CPU Idle calls when Linux is idle (unless this
1863          feature is turned off -- see "Do CPU IDLE calls", below). This
1864          should always save battery power, but more complicated APM features
1865          will be dependent on your BIOS implementation. You may need to turn
1866          this option off if your computer hangs at boot time when using APM
1867          support, or if it beeps continuously instead of suspending. Turn
1868          this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1869          T400CDT. This is off by default since most machines do fine without
1870          this feature.
1871
1872config APM_CPU_IDLE
1873        bool "Make CPU Idle calls when idle"
1874        ---help---
1875          Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1876          On some machines, this can activate improved power savings, such as
1877          a slowed CPU clock rate, when the machine is idle. These idle calls
1878          are made after the idle loop has run for some length of time (e.g.,
1879          333 mS). On some machines, this will cause a hang at boot time or
1880          whenever the CPU becomes idle. (On machines with more than one CPU,
1881          this option does nothing.)
1882
1883config APM_DISPLAY_BLANK
1884        bool "Enable console blanking using APM"
1885        ---help---
1886          Enable console blanking using the APM. Some laptops can use this to
1887          turn off the LCD backlight when the screen blanker of the Linux
1888          virtual console blanks the screen. Note that this is only used by
1889          the virtual console screen blanker, and won't turn off the backlight
1890          when using the X Window system. This also doesn't have anything to
1891          do with your VESA-compliant power-saving monitor. Further, this
1892          option doesn't work for all laptops -- it might not turn off your
1893          backlight at all, or it might print a lot of errors to the console,
1894          especially if you are using gpm.
1895
1896config APM_ALLOW_INTS
1897        bool "Allow interrupts during APM BIOS calls"
1898        ---help---
1899          Normally we disable external interrupts while we are making calls to
1900          the APM BIOS as a measure to lessen the effects of a badly behaving
1901          BIOS implementation.  The BIOS should reenable interrupts if it
1902          needs to.  Unfortunately, some BIOSes do not -- especially those in
1903          many of the newer IBM Thinkpads.  If you experience hangs when you
1904          suspend, try setting this to Y.  Otherwise, say N.
1905
1906endif # APM
1907
1908source "drivers/cpufreq/Kconfig"
1909
1910source "drivers/cpuidle/Kconfig"
1911
1912source "drivers/idle/Kconfig"
1913
1914endmenu
1915
1916
1917menu "Bus options (PCI etc.)"
1918
1919config PCI
1920        bool "PCI support"
1921        default y
1922        select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1923        ---help---
1924          Find out whether you have a PCI motherboard. PCI is the name of a
1925          bus system, i.e. the way the CPU talks to the other stuff inside
1926          your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1927          VESA. If you have PCI, say Y, otherwise N.
1928
1929choice
1930        prompt "PCI access mode"
1931        depends on X86_32 && PCI
1932        default PCI_GOANY
1933        ---help---
1934          On PCI systems, the BIOS can be used to detect the PCI devices and
1935          determine their configuration. However, some old PCI motherboards
1936          have BIOS bugs and may crash if this is done. Also, some embedded
1937          PCI-based systems don't have any BIOS at all. Linux can also try to
1938          detect the PCI hardware directly without using the BIOS.
1939
1940          With this option, you can specify how Linux should detect the
1941          PCI devices. If you choose "BIOS", the BIOS will be used,
1942          if you choose "Direct", the BIOS won't be used, and if you
1943          choose "MMConfig", then PCI Express MMCONFIG will be used.
1944          If you choose "Any", the kernel will try MMCONFIG, then the
1945          direct access method and falls back to the BIOS if that doesn't
1946          work. If unsure, go with the default, which is "Any".
1947
1948config PCI_GOBIOS
1949        bool "BIOS"
1950
1951config PCI_GOMMCONFIG
1952        bool "MMConfig"
1953
1954config PCI_GODIRECT
1955        bool "Direct"
1956
1957config PCI_GOOLPC
1958        bool "OLPC XO-1"
1959        depends on OLPC
1960
1961config PCI_GOANY
1962        bool "Any"
1963
1964endchoice
1965
1966config PCI_BIOS
1967        def_bool y
1968        depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1969
1970# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1971config PCI_DIRECT
1972        def_bool y
1973        depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
1974
1975config PCI_MMCONFIG
1976        def_bool y
1977        depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
1978
1979config PCI_OLPC
1980        def_bool y
1981        depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1982
1983config PCI_XEN
1984        def_bool y
1985        depends on PCI && XEN
1986        select SWIOTLB_XEN
1987
1988config PCI_DOMAINS
1989        def_bool y
1990        depends on PCI
1991
1992config PCI_MMCONFIG
1993        bool "Support mmconfig PCI config space access"
1994        depends on X86_64 && PCI && ACPI
1995
1996config PCI_CNB20LE_QUIRK
1997        bool "Read CNB20LE Host Bridge Windows" if EXPERT
1998        depends on PCI && EXPERIMENTAL
1999        help
2000          Read the PCI windows out of the CNB20LE host bridge. This allows
2001          PCI hotplug to work on systems with the CNB20LE chipset which do
2002          not have ACPI.
2003
2004          There's no public spec for this chipset, and this functionality
2005          is known to be incomplete.
2006
2007          You should say N unless you know you need this.
2008
2009source "drivers/pci/pcie/Kconfig"
2010
2011source "drivers/pci/Kconfig"
2012
2013# x86_64 have no ISA slots, but can have ISA-style DMA.
2014config ISA_DMA_API
2015        bool "ISA-style DMA support" if (X86_64 && EXPERT)
2016        default y
2017        help
2018          Enables ISA-style DMA support for devices requiring such controllers.
2019          If unsure, say Y.
2020
2021if X86_32
2022
2023config ISA
2024        bool "ISA support"
2025        ---help---
2026          Find out whether you have ISA slots on your motherboard.  ISA is the
2027          name of a bus system, i.e. the way the CPU talks to the other stuff
2028          inside your box.  Other bus systems are PCI, EISA, MicroChannel
2029          (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
2030          newer boards don't support it.  If you have ISA, say Y, otherwise N.
2031
2032config EISA
2033        bool "EISA support"
2034        depends on ISA
2035        ---help---
2036          The Extended Industry Standard Architecture (EISA) bus was
2037          developed as an open alternative to the IBM MicroChannel bus.
2038
2039          The EISA bus provided some of the features of the IBM MicroChannel
2040          bus while maintaining backward compatibility with cards made for
2041          the older ISA bus.  The EISA bus saw limited use between 1988 and
2042          1995 when it was made obsolete by the PCI bus.
2043
2044          Say Y here if you are building a kernel for an EISA-based machine.
2045
2046          Otherwise, say N.
2047
2048source "drivers/eisa/Kconfig"
2049
2050config SCx200
2051        tristate "NatSemi SCx200 support"
2052        ---help---
2053          This provides basic support for National Semiconductor's
2054          (now AMD's) Geode processors.  The driver probes for the
2055          PCI-IDs of several on-chip devices, so its a good dependency
2056          for other scx200_* drivers.
2057
2058          If compiled as a module, the driver is named scx200.
2059
2060config SCx200HR_TIMER
2061        tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2062        depends on SCx200
2063        default y
2064        ---help---
2065          This driver provides a clocksource built upon the on-chip
2066          27MHz high-resolution timer.  Its also a workaround for
2067          NSC Geode SC-1100's buggy TSC, which loses time when the
2068          processor goes idle (as is done by the scheduler).  The
2069          other workaround is idle=poll boot option.
2070
2071config OLPC
2072        bool "One Laptop Per Child support"
2073        depends on !X86_PAE
2074        select GPIOLIB
2075        select OF
2076        select OF_PROMTREE
2077        select IRQ_DOMAIN
2078        ---help---
2079          Add support for detecting the unique features of the OLPC
2080          XO hardware.
2081
2082config OLPC_XO1_PM
2083        bool "OLPC XO-1 Power Management"
2084        depends on OLPC && MFD_CS5535 && PM_SLEEP
2085        select MFD_CORE
2086        ---help---
2087          Add support for poweroff and suspend of the OLPC XO-1 laptop.
2088
2089config OLPC_XO1_RTC
2090        bool "OLPC XO-1 Real Time Clock"
2091        depends on OLPC_XO1_PM && RTC_DRV_CMOS
2092        ---help---
2093          Add support for the XO-1 real time clock, which can be used as a
2094          programmable wakeup source.
2095
2096config OLPC_XO1_SCI
2097        bool "OLPC XO-1 SCI extras"
2098        depends on OLPC && OLPC_XO1_PM
2099        select POWER_SUPPLY
2100        select GPIO_CS5535
2101        select MFD_CORE
2102        ---help---
2103          Add support for SCI-based features of the OLPC XO-1 laptop:
2104           - EC-driven system wakeups
2105           - Power button
2106           - Ebook switch
2107           - Lid switch
2108           - AC adapter status updates
2109           - Battery status updates
2110
2111config OLPC_XO15_SCI
2112        bool "OLPC XO-1.5 SCI extras"
2113        depends on OLPC && ACPI
2114        select POWER_SUPPLY
2115        ---help---
2116          Add support for SCI-based features of the OLPC XO-1.5 laptop:
2117           - EC-driven system wakeups
2118           - AC adapter status updates
2119           - Battery status updates
2120
2121config ALIX
2122        bool "PCEngines ALIX System Support (LED setup)"
2123        select GPIOLIB
2124        ---help---
2125          This option enables system support for the PCEngines ALIX.
2126          At present this just sets up LEDs for GPIO control on
2127          ALIX2/3/6 boards.  However, other system specific setup should
2128          get added here.
2129
2130          Note: You must still enable the drivers for GPIO and LED support
2131          (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2132
2133          Note: You have to set alix.force=1 for boards with Award BIOS.
2134
2135config NET5501
2136        bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2137        select GPIOLIB
2138        ---help---
2139          This option enables system support for the Soekris Engineering net5501.
2140
2141config GEOS
2142        bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2143        select GPIOLIB
2144        depends on DMI
2145        ---help---
2146          This option enables system support for the Traverse Technologies GEOS.
2147
2148endif # X86_32
2149
2150config AMD_NB
2151        def_bool y
2152        depends on CPU_SUP_AMD && PCI
2153
2154source "drivers/pcmcia/Kconfig"
2155
2156source "drivers/pci/hotplug/Kconfig"
2157
2158config RAPIDIO
2159        bool "RapidIO support"
2160        depends on PCI
2161        default n
2162        help
2163          If you say Y here, the kernel will include drivers and
2164          infrastructure code to support RapidIO interconnect devices.
2165
2166source "drivers/rapidio/Kconfig"
2167
2168endmenu
2169
2170
2171menu "Executable file formats / Emulations"
2172
2173source "fs/Kconfig.binfmt"
2174
2175config IA32_EMULATION
2176        bool "IA32 Emulation"
2177        depends on X86_64
2178        select COMPAT_BINFMT_ELF
2179        select HAVE_UID16
2180        ---help---
2181          Include code to run legacy 32-bit programs under a
2182          64-bit kernel. You should likely turn this on, unless you're
2183          100% sure that you don't have any 32-bit programs left.
2184
2185config IA32_AOUT
2186        tristate "IA32 a.out support"
2187        depends on IA32_EMULATION
2188        ---help---
2189          Support old a.out binaries in the 32bit emulation.
2190
2191config X86_X32
2192        bool "x32 ABI for 64-bit mode (EXPERIMENTAL)"
2193        depends on X86_64 && IA32_EMULATION && EXPERIMENTAL
2194        ---help---
2195          Include code to run binaries for the x32 native 32-bit ABI
2196          for 64-bit processors.  An x32 process gets access to the
2197          full 64-bit register file and wide data path while leaving
2198          pointers at 32 bits for smaller memory footprint.
2199
2200          You will need a recent binutils (2.22 or later) with
2201          elf32_x86_64 support enabled to compile a kernel with this
2202          option set.
2203
2204config COMPAT
2205        def_bool y
2206        depends on IA32_EMULATION || X86_X32
2207        select ARCH_WANT_OLD_COMPAT_IPC
2208
2209if COMPAT
2210config COMPAT_FOR_U64_ALIGNMENT
2211        def_bool y
2212
2213config SYSVIPC_COMPAT
2214        def_bool y
2215        depends on SYSVIPC
2216
2217config KEYS_COMPAT
2218        def_bool y
2219        depends on KEYS
2220endif
2221
2222endmenu
2223
2224
2225config HAVE_ATOMIC_IOMAP
2226        def_bool y
2227        depends on X86_32
2228
2229config HAVE_TEXT_POKE_SMP
2230        bool
2231        select STOP_MACHINE if SMP
2232
2233config X86_DEV_DMA_OPS
2234        bool
2235        depends on X86_64 || STA2X11
2236
2237config X86_DMA_REMAP
2238        bool
2239        depends on STA2X11
2240
2241source "net/Kconfig"
2242
2243source "drivers/Kconfig"
2244
2245source "drivers/firmware/Kconfig"
2246
2247source "fs/Kconfig"
2248
2249source "arch/x86/Kconfig.debug"
2250
2251source "security/Kconfig"
2252
2253source "crypto/Kconfig"
2254
2255source "arch/x86/kvm/Kconfig"
2256
2257source "lib/Kconfig"
2258
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