arch/x86/Kconfig

   1 # Select 32 or 64 bit
   2 config 64BIT
   3         bool "64-bit kernel" if ARCH = "x86"
   4         default ARCH = "x86_64"
   5         ---help---
   6           Say yes to build a 64-bit kernel - formerly known as x86_64
   7           Say no to build a 32-bit kernel - formerly known as i386
   8
   9 config X86_32
  10         def_bool !64BIT
  11
  12 config X86_64
  13         def_bool 64BIT
  14
  15 ### Arch settings
  16 config X86
  17         def_bool y
  18         select HAVE_AOUT if X86_32
  19         select HAVE_READQ
  20         select HAVE_WRITEQ
  21         select HAVE_UNSTABLE_SCHED_CLOCK
  22         select HAVE_IDE
  23         select HAVE_OPROFILE
  24         select HAVE_PERF_EVENTS if (!M386 && !M486)
  25         select HAVE_IRQ_WORK
  26         select HAVE_IOREMAP_PROT
  27         select HAVE_KPROBES
  28         select HAVE_MEMBLOCK
  29         select ARCH_WANT_OPTIONAL_GPIOLIB
  30         select ARCH_WANT_FRAME_POINTERS
  31         select HAVE_DMA_ATTRS
  32         select HAVE_KRETPROBES
  33         select HAVE_OPTPROBES
  34         select HAVE_FTRACE_MCOUNT_RECORD
  35         select HAVE_C_RECORDMCOUNT
  36         select HAVE_DYNAMIC_FTRACE
  37         select HAVE_FUNCTION_TRACER
  38         select HAVE_FUNCTION_GRAPH_TRACER
  39         select HAVE_FUNCTION_GRAPH_FP_TEST
  40         select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  41         select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
  42         select HAVE_SYSCALL_TRACEPOINTS
  43         select HAVE_KVM
  44         select HAVE_ARCH_KGDB
  45         select HAVE_ARCH_TRACEHOOK
  46         select HAVE_GENERIC_DMA_COHERENT if X86_32
  47         select HAVE_EFFICIENT_UNALIGNED_ACCESS
  48         select USER_STACKTRACE_SUPPORT
  49         select HAVE_REGS_AND_STACK_ACCESS_API
  50         select HAVE_DMA_API_DEBUG
  51         select HAVE_KERNEL_GZIP
  52         select HAVE_KERNEL_BZIP2
  53         select HAVE_KERNEL_LZMA
  54         select HAVE_KERNEL_LZO
  55         select HAVE_HW_BREAKPOINT
  56         select HAVE_MIXED_BREAKPOINTS_REGS
  57         select PERF_EVENTS
  58         select HAVE_PERF_EVENTS_NMI
  59         select ANON_INODES
  60         select HAVE_ARCH_KMEMCHECK
  61         select HAVE_USER_RETURN_NOTIFIER
  62         select HAVE_ARCH_JUMP_LABEL
  63         select HAVE_TEXT_POKE_SMP
  64         select HAVE_GENERIC_HARDIRQS
  65         select HAVE_SPARSE_IRQ
  66         select GENERIC_IRQ_PROBE
  67         select GENERIC_PENDING_IRQ if SMP
  68
  69 config INSTRUCTION_DECODER
  70         def_bool (KPROBES || PERF_EVENTS)
  71
  72 config OUTPUT_FORMAT
  73         string
  74         default "elf32-i386" if X86_32
  75         default "elf64-x86-64" if X86_64
  76
  77 config ARCH_DEFCONFIG
  78         string
  79         default "arch/x86/configs/i386_defconfig" if X86_32
  80         default "arch/x86/configs/x86_64_defconfig" if X86_64
  81
  82 config GENERIC_CMOS_UPDATE
  83         def_bool y
  84
  85 config CLOCKSOURCE_WATCHDOG
  86         def_bool y
  87
  88 config GENERIC_CLOCKEVENTS
  89         def_bool y
  90
  91 config GENERIC_CLOCKEVENTS_BROADCAST
  92         def_bool y
  93         depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  94
  95 config LOCKDEP_SUPPORT
  96         def_bool y
  97
  98 config STACKTRACE_SUPPORT
  99         def_bool y
 100
 101 config HAVE_LATENCYTOP_SUPPORT
 102         def_bool y
 103
 104 config MMU
 105         def_bool y
 106
 107 config ZONE_DMA
 108         def_bool y
 109
 110 config SBUS
 111         bool
 112
 113 config NEED_DMA_MAP_STATE
 114        def_bool (X86_64 || DMAR || DMA_API_DEBUG)
 115
 116 config NEED_SG_DMA_LENGTH
 117         def_bool y
 118
 119 config GENERIC_ISA_DMA
 120         def_bool y
 121
 122 config GENERIC_IOMAP
 123         def_bool y
 124
 125 config GENERIC_BUG
 126         def_bool y
 127         depends on BUG
 128         select GENERIC_BUG_RELATIVE_POINTERS if X86_64
 129
 130 config GENERIC_BUG_RELATIVE_POINTERS
 131         bool
 132
 133 config GENERIC_HWEIGHT
 134         def_bool y
 135
 136 config GENERIC_GPIO
 137         bool
 138
 139 config ARCH_MAY_HAVE_PC_FDC
 140         def_bool y
 141
 142 config RWSEM_GENERIC_SPINLOCK
 143         def_bool !X86_XADD
 144
 145 config RWSEM_XCHGADD_ALGORITHM
 146         def_bool X86_XADD
 147
 148 config ARCH_HAS_CPU_IDLE_WAIT
 149         def_bool y
 150
 151 config GENERIC_CALIBRATE_DELAY
 152         def_bool y
 153
 154 config GENERIC_TIME_VSYSCALL
 155         bool
 156         default X86_64
 157
 158 config ARCH_HAS_CPU_RELAX
 159         def_bool y
 160
 161 config ARCH_HAS_DEFAULT_IDLE
 162         def_bool y
 163
 164 config ARCH_HAS_CACHE_LINE_SIZE
 165         def_bool y
 166
 167 config HAVE_SETUP_PER_CPU_AREA
 168         def_bool y
 169
 170 config NEED_PER_CPU_EMBED_FIRST_CHUNK
 171         def_bool y
 172
 173 config NEED_PER_CPU_PAGE_FIRST_CHUNK
 174         def_bool y
 175
 176 config HAVE_CPUMASK_OF_CPU_MAP
 177         def_bool X86_64_SMP
 178
 179 config ARCH_HIBERNATION_POSSIBLE
 180         def_bool y
 181
 182 config ARCH_SUSPEND_POSSIBLE
 183         def_bool y
 184
 185 config ZONE_DMA32
 186         bool
 187         default X86_64
 188
 189 config ARCH_POPULATES_NODE_MAP
 190         def_bool y
 191
 192 config AUDIT_ARCH
 193         bool
 194         default X86_64
 195
 196 config ARCH_SUPPORTS_OPTIMIZED_INLINING
 197         def_bool y
 198
 199 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
 200         def_bool y
 201
 202 config HAVE_INTEL_TXT
 203         def_bool y
 204         depends on EXPERIMENTAL && DMAR && ACPI
 205
 206 config USE_GENERIC_SMP_HELPERS
 207         def_bool y
 208         depends on SMP
 209
 210 config X86_32_SMP
 211         def_bool y
 212         depends on X86_32 && SMP
 213
 214 config X86_64_SMP
 215         def_bool y
 216         depends on X86_64 && SMP
 217
 218 config X86_HT
 219         def_bool y
 220         depends on SMP
 221
 222 config X86_TRAMPOLINE
 223         def_bool y
 224         depends on SMP || (64BIT && ACPI_SLEEP)
 225
 226 config X86_32_LAZY_GS
 227         def_bool y
 228         depends on X86_32 && !CC_STACKPROTECTOR
 229
 230 config ARCH_HWEIGHT_CFLAGS
 231         string
 232         default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
 233         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
 234
 235 config KTIME_SCALAR
 236         def_bool X86_32
 237
 238 config ARCH_CPU_PROBE_RELEASE
 239         def_bool y
 240         depends on HOTPLUG_CPU
 241
 242 source "init/Kconfig"
 243 source "kernel/Kconfig.freezer"
 244
 245 menu "Processor type and features"
 246
 247 source "kernel/time/Kconfig"
 248
 249 config SMP
 250         bool "Symmetric multi-processing support"
 251         ---help---
 252           This enables support for systems with more than one CPU. If you have
 253           a system with only one CPU, like most personal computers, say N. If
 254           you have a system with more than one CPU, say Y.
 255
 256           If you say N here, the kernel will run on single and multiprocessor
 257           machines, but will use only one CPU of a multiprocessor machine. If
 258           you say Y here, the kernel will run on many, but not all,
 259           singleprocessor machines. On a singleprocessor machine, the kernel
 260           will run faster if you say N here.
 261
 262           Note that if you say Y here and choose architecture "586" or
 263           "Pentium" under "Processor family", the kernel will not work on 486
 264           architectures. Similarly, multiprocessor kernels for the "PPro"
 265           architecture may not work on all Pentium based boards.
 266
 267           People using multiprocessor machines who say Y here should also say
 268           Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
 269           Management" code will be disabled if you say Y here.
 270
 271           See also <file:Documentation/i386/IO-APIC.txt>,
 272           <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
 273           <http://www.tldp.org/docs.html#howto>.
 274
 275           If you don't know what to do here, say N.
 276
 277 config X86_X2APIC
 278         bool "Support x2apic"
 279         depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
 280         ---help---
 281           This enables x2apic support on CPUs that have this feature.
 282
 283           This allows 32-bit apic IDs (so it can support very large systems),
 284           and accesses the local apic via MSRs not via mmio.
 285
 286           If you don't know what to do here, say N.
 287
 288 config X86_MPPARSE
 289         bool "Enable MPS table" if ACPI
 290         default y
 291         depends on X86_LOCAL_APIC
 292         ---help---
 293           For old smp systems that do not have proper acpi support. Newer systems
 294           (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
 295
 296 config X86_BIGSMP
 297         bool "Support for big SMP systems with more than 8 CPUs"
 298         depends on X86_32 && SMP
 299         ---help---
 300           This option is needed for the systems that have more than 8 CPUs
 301
 302 if X86_32
 303 config X86_EXTENDED_PLATFORM
 304         bool "Support for extended (non-PC) x86 platforms"
 305         default y
 306         ---help---
 307           If you disable this option then the kernel will only support
 308           standard PC platforms. (which covers the vast majority of
 309           systems out there.)
 310
 311           If you enable this option then you'll be able to select support
 312           for the following (non-PC) 32 bit x86 platforms:
 313                 AMD Elan
 314                 NUMAQ (IBM/Sequent)
 315                 RDC R-321x SoC
 316                 SGI 320/540 (Visual Workstation)
 317                 Summit/EXA (IBM x440)
 318                 Unisys ES7000 IA32 series
 319                 Moorestown MID devices
 320
 321           If you have one of these systems, or if you want to build a
 322           generic distribution kernel, say Y here - otherwise say N.
 323 endif
 324
 325 if X86_64
 326 config X86_EXTENDED_PLATFORM
 327         bool "Support for extended (non-PC) x86 platforms"
 328         default y
 329         ---help---
 330           If you disable this option then the kernel will only support
 331           standard PC platforms. (which covers the vast majority of
 332           systems out there.)
 333
 334           If you enable this option then you'll be able to select support
 335           for the following (non-PC) 64 bit x86 platforms:
 336                 ScaleMP vSMP
 337                 SGI Ultraviolet
 338
 339           If you have one of these systems, or if you want to build a
 340           generic distribution kernel, say Y here - otherwise say N.
 341 endif
 342 # This is an alphabetically sorted list of 64 bit extended platforms
 343 # Please maintain the alphabetic order if and when there are additions
 344
 345 config X86_VSMP
 346         bool "ScaleMP vSMP"
 347         select PARAVIRT_GUEST
 348         select PARAVIRT
 349         depends on X86_64 && PCI
 350         depends on X86_EXTENDED_PLATFORM
 351         ---help---
 352           Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
 353           supposed to run on these EM64T-based machines.  Only choose this option
 354           if you have one of these machines.
 355
 356 config X86_UV
 357         bool "SGI Ultraviolet"
 358         depends on X86_64
 359         depends on X86_EXTENDED_PLATFORM
 360         depends on NUMA
 361         depends on X86_X2APIC
 362         ---help---
 363           This option is needed in order to support SGI Ultraviolet systems.
 364           If you don't have one of these, you should say N here.
 365
 366 # Following is an alphabetically sorted list of 32 bit extended platforms
 367 # Please maintain the alphabetic order if and when there are additions
 368
 369 config X86_ELAN
 370         bool "AMD Elan"
 371         depends on X86_32
 372         depends on X86_EXTENDED_PLATFORM
 373         ---help---
 374           Select this for an AMD Elan processor.
 375
 376           Do not use this option for K6/Athlon/Opteron processors!
 377
 378           If unsure, choose "PC-compatible" instead.
 379
 380 config X86_MRST
 381        bool "Moorestown MID platform"
 382         depends on PCI
 383         depends on PCI_GOANY
 384         depends on X86_32
 385         depends on X86_EXTENDED_PLATFORM
 386         depends on X86_IO_APIC
 387         select APB_TIMER
 388         ---help---
 389           Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
 390           Internet Device(MID) platform. Moorestown consists of two chips:
 391           Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
 392           Unlike standard x86 PCs, Moorestown does not have many legacy devices
 393           nor standard legacy replacement devices/features. e.g. Moorestown does
 394           not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
 395
 396 config X86_RDC321X
 397         bool "RDC R-321x SoC"
 398         depends on X86_32
 399         depends on X86_EXTENDED_PLATFORM
 400         select M486
 401         select X86_REBOOTFIXUPS
 402         ---help---
 403           This option is needed for RDC R-321x system-on-chip, also known
 404           as R-8610-(G).
 405           If you don't have one of these chips, you should say N here.
 406
 407 config X86_32_NON_STANDARD
 408         bool "Support non-standard 32-bit SMP architectures"
 409         depends on X86_32 && SMP
 410         depends on X86_EXTENDED_PLATFORM
 411         ---help---
 412           This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
 413           subarchitectures.  It is intended for a generic binary kernel.
 414           if you select them all, kernel will probe it one by one. and will
 415           fallback to default.
 416
 417 # Alphabetically sorted list of Non standard 32 bit platforms
 418
 419 config X86_NUMAQ
 420         bool "NUMAQ (IBM/Sequent)"
 421         depends on X86_32_NON_STANDARD
 422         depends on PCI
 423         select NUMA
 424         select X86_MPPARSE
 425         ---help---
 426           This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
 427           NUMA multiquad box. This changes the way that processors are
 428           bootstrapped, and uses Clustered Logical APIC addressing mode instead
 429           of Flat Logical.  You will need a new lynxer.elf file to flash your
 430           firmware with - send email to <Martin.Bligh@us.ibm.com>.
 431
 432 config X86_SUPPORTS_MEMORY_FAILURE
 433         def_bool y
 434         # MCE code calls memory_failure():
 435         depends on X86_MCE
 436         # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
 437         depends on !X86_NUMAQ
 438         # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
 439         depends on X86_64 || !SPARSEMEM
 440         select ARCH_SUPPORTS_MEMORY_FAILURE
 441
 442 config X86_VISWS
 443         bool "SGI 320/540 (Visual Workstation)"
 444         depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
 445         depends on X86_32_NON_STANDARD
 446         ---help---
 447           The SGI Visual Workstation series is an IA32-based workstation
 448           based on SGI systems chips with some legacy PC hardware attached.
 449
 450           Say Y here to create a kernel to run on the SGI 320 or 540.
 451
 452           A kernel compiled for the Visual Workstation will run on general
 453           PCs as well. See <file:Documentation/sgi-visws.txt> for details.
 454
 455 config X86_SUMMIT
 456         bool "Summit/EXA (IBM x440)"
 457         depends on X86_32_NON_STANDARD
 458         ---help---
 459           This option is needed for IBM systems that use the Summit/EXA chipset.
 460           In particular, it is needed for the x440.
 461
 462 config X86_ES7000
 463         bool "Unisys ES7000 IA32 series"
 464         depends on X86_32_NON_STANDARD && X86_BIGSMP
 465         ---help---
 466           Support for Unisys ES7000 systems.  Say 'Y' here if this kernel is
 467           supposed to run on an IA32-based Unisys ES7000 system.
 468
 469 config SCHED_OMIT_FRAME_POINTER
 470         def_bool y
 471         prompt "Single-depth WCHAN output"
 472         depends on X86
 473         ---help---
 474           Calculate simpler /proc/<PID>/wchan values. If this option
 475           is disabled then wchan values will recurse back to the
 476           caller function. This provides more accurate wchan values,
 477           at the expense of slightly more scheduling overhead.
 478
 479           If in doubt, say "Y".
 480
 481 menuconfig PARAVIRT_GUEST
 482         bool "Paravirtualized guest support"
 483         ---help---
 484           Say Y here to get to see options related to running Linux under
 485           various hypervisors.  This option alone does not add any kernel code.
 486
 487           If you say N, all options in this submenu will be skipped and disabled.
 488
 489 if PARAVIRT_GUEST
 490
 491 source "arch/x86/xen/Kconfig"
 492
 493 config KVM_CLOCK
 494         bool "KVM paravirtualized clock"
 495         select PARAVIRT
 496         select PARAVIRT_CLOCK
 497         ---help---
 498           Turning on this option will allow you to run a paravirtualized clock
 499           when running over the KVM hypervisor. Instead of relying on a PIT
 500           (or probably other) emulation by the underlying device model, the host
 501           provides the guest with timing infrastructure such as time of day, and
 502           system time
 503
 504 config KVM_GUEST
 505         bool "KVM Guest support"
 506         select PARAVIRT
 507         ---help---
 508           This option enables various optimizations for running under the KVM
 509           hypervisor.
 510
 511 source "arch/x86/lguest/Kconfig"
 512
 513 config PARAVIRT
 514         bool "Enable paravirtualization code"
 515         ---help---
 516           This changes the kernel so it can modify itself when it is run
 517           under a hypervisor, potentially improving performance significantly
 518           over full virtualization.  However, when run without a hypervisor
 519           the kernel is theoretically slower and slightly larger.
 520
 521 config PARAVIRT_SPINLOCKS
 522         bool "Paravirtualization layer for spinlocks"
 523         depends on PARAVIRT && SMP && EXPERIMENTAL
 524         ---help---
 525           Paravirtualized spinlocks allow a pvops backend to replace the
 526           spinlock implementation with something virtualization-friendly
 527           (for example, block the virtual CPU rather than spinning).
 528
 529           Unfortunately the downside is an up to 5% performance hit on
 530           native kernels, with various workloads.
 531
 532           If you are unsure how to answer this question, answer N.
 533
 534 config PARAVIRT_CLOCK
 535         bool
 536
 537 endif
 538
 539 config PARAVIRT_DEBUG
 540         bool "paravirt-ops debugging"
 541         depends on PARAVIRT && DEBUG_KERNEL
 542         ---help---
 543           Enable to debug paravirt_ops internals.  Specifically, BUG if
 544           a paravirt_op is missing when it is called.
 545
 546 config NO_BOOTMEM
 547         def_bool y
 548
 549 config MEMTEST
 550         bool "Memtest"
 551         ---help---
 552           This option adds a kernel parameter 'memtest', which allows memtest
 553           to be set.
 554                 memtest=0, mean disabled; -- default
 555                 memtest=1, mean do 1 test pattern;
 556                 ...
 557                 memtest=4, mean do 4 test patterns.
 558           If you are unsure how to answer this question, answer N.
 559
 560 config X86_SUMMIT_NUMA
 561         def_bool y
 562         depends on X86_32 && NUMA && X86_32_NON_STANDARD
 563
 564 config X86_CYCLONE_TIMER
 565         def_bool y
 566         depends on X86_32_NON_STANDARD
 567
 568 source "arch/x86/Kconfig.cpu"
 569
 570 config HPET_TIMER
 571         def_bool X86_64
 572         prompt "HPET Timer Support" if X86_32
 573         ---help---
 574           Use the IA-PC HPET (High Precision Event Timer) to manage
 575           time in preference to the PIT and RTC, if a HPET is
 576           present.
 577           HPET is the next generation timer replacing legacy 8254s.
 578           The HPET provides a stable time base on SMP
 579           systems, unlike the TSC, but it is more expensive to access,
 580           as it is off-chip.  You can find the HPET spec at
 581           <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
 582
 583           You can safely choose Y here.  However, HPET will only be
 584           activated if the platform and the BIOS support this feature.
 585           Otherwise the 8254 will be used for timing services.
 586
 587           Choose N to continue using the legacy 8254 timer.
 588
 589 config HPET_EMULATE_RTC
 590         def_bool y
 591         depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
 592
 593 config APB_TIMER
 594        def_bool y if MRST
 595        prompt "Langwell APB Timer Support" if X86_MRST
 596        help
 597          APB timer is the replacement for 8254, HPET on X86 MID platforms.
 598          The APBT provides a stable time base on SMP
 599          systems, unlike the TSC, but it is more expensive to access,
 600          as it is off-chip. APB timers are always running regardless of CPU
 601          C states, they are used as per CPU clockevent device when possible.
 602
 603 # Mark as embedded because too many people got it wrong.
 604 # The code disables itself when not needed.
 605 config DMI
 606         default y
 607         bool "Enable DMI scanning" if EMBEDDED
 608         ---help---
 609           Enabled scanning of DMI to identify machine quirks. Say Y
 610           here unless you have verified that your setup is not
 611           affected by entries in the DMI blacklist. Required by PNP
 612           BIOS code.
 613
 614 config GART_IOMMU
 615         bool "GART IOMMU support" if EMBEDDED
 616         default y
 617         select SWIOTLB
 618         depends on X86_64 && PCI && AMD_NB
 619         ---help---
 620           Support for full DMA access of devices with 32bit memory access only
 621           on systems with more than 3GB. This is usually needed for USB,
 622           sound, many IDE/SATA chipsets and some other devices.
 623           Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
 624           based hardware IOMMU and a software bounce buffer based IOMMU used
 625           on Intel systems and as fallback.
 626           The code is only active when needed (enough memory and limited
 627           device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
 628           too.
 629
 630 config CALGARY_IOMMU
 631         bool "IBM Calgary IOMMU support"
 632         select SWIOTLB
 633         depends on X86_64 && PCI && EXPERIMENTAL
 634         ---help---
 635           Support for hardware IOMMUs in IBM's xSeries x366 and x460
 636           systems. Needed to run systems with more than 3GB of memory
 637           properly with 32-bit PCI devices that do not support DAC
 638           (Double Address Cycle). Calgary also supports bus level
 639           isolation, where all DMAs pass through the IOMMU.  This
 640           prevents them from going anywhere except their intended
 641           destination. This catches hard-to-find kernel bugs and
 642           mis-behaving drivers and devices that do not use the DMA-API
 643           properly to set up their DMA buffers.  The IOMMU can be
 644           turned off at boot time with the iommu=off parameter.
 645           Normally the kernel will make the right choice by itself.
 646           If unsure, say Y.
 647
 648 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
 649         def_bool y
 650         prompt "Should Calgary be enabled by default?"
 651         depends on CALGARY_IOMMU
 652         ---help---
 653           Should Calgary be enabled by default? if you choose 'y', Calgary
 654           will be used (if it exists). If you choose 'n', Calgary will not be
 655           used even if it exists. If you choose 'n' and would like to use
 656           Calgary anyway, pass 'iommu=calgary' on the kernel command line.
 657           If unsure, say Y.
 658
 659 config AMD_IOMMU
 660         bool "AMD IOMMU support"
 661         select SWIOTLB
 662         select PCI_MSI
 663         depends on X86_64 && PCI && ACPI
 664         ---help---
 665           With this option you can enable support for AMD IOMMU hardware in
 666           your system. An IOMMU is a hardware component which provides
 667           remapping of DMA memory accesses from devices. With an AMD IOMMU you
 668           can isolate the the DMA memory of different devices and protect the
 669           system from misbehaving device drivers or hardware.
 670
 671           You can find out if your system has an AMD IOMMU if you look into
 672           your BIOS for an option to enable it or if you have an IVRS ACPI
 673           table.
 674
 675 config AMD_IOMMU_STATS
 676         bool "Export AMD IOMMU statistics to debugfs"
 677         depends on AMD_IOMMU
 678         select DEBUG_FS
 679         ---help---
 680           This option enables code in the AMD IOMMU driver to collect various
 681           statistics about whats happening in the driver and exports that
 682           information to userspace via debugfs.
 683           If unsure, say N.
 684
 685 # need this always selected by IOMMU for the VIA workaround
 686 config SWIOTLB
 687         def_bool y if X86_64
 688         ---help---
 689           Support for software bounce buffers used on x86-64 systems
 690           which don't have a hardware IOMMU (e.g. the current generation
 691           of Intel's x86-64 CPUs). Using this PCI devices which can only
 692           access 32-bits of memory can be used on systems with more than
 693           3 GB of memory. If unsure, say Y.
 694
 695 config IOMMU_HELPER
 696         def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
 697
 698 config IOMMU_API
 699         def_bool (AMD_IOMMU || DMAR)
 700
 701 config MAXSMP
 702         bool "Enable Maximum number of SMP Processors and NUMA Nodes"
 703         depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
 704         select CPUMASK_OFFSTACK
 705         ---help---
 706           Enable maximum number of CPUS and NUMA Nodes for this architecture.
 707           If unsure, say N.
 708
 709 config NR_CPUS
 710         int "Maximum number of CPUs" if SMP && !MAXSMP
 711         range 2 8 if SMP && X86_32 && !X86_BIGSMP
 712         range 2 512 if SMP && !MAXSMP
 713         default "1" if !SMP
 714         default "4096" if MAXSMP
 715         default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
 716         default "8" if SMP
 717         ---help---
 718           This allows you to specify the maximum number of CPUs which this
 719           kernel will support.  The maximum supported value is 512 and the
 720           minimum value which makes sense is 2.
 721
 722           This is purely to save memory - each supported CPU adds
 723           approximately eight kilobytes to the kernel image.
 724
 725 config SCHED_SMT
 726         bool "SMT (Hyperthreading) scheduler support"
 727         depends on X86_HT
 728         ---help---
 729           SMT scheduler support improves the CPU scheduler's decision making
 730           when dealing with Intel Pentium 4 chips with HyperThreading at a
 731           cost of slightly increased overhead in some places. If unsure say
 732           N here.
 733
 734 config SCHED_MC
 735         def_bool y
 736         prompt "Multi-core scheduler support"
 737         depends on X86_HT
 738         ---help---
 739           Multi-core scheduler support improves the CPU scheduler's decision
 740           making when dealing with multi-core CPU chips at a cost of slightly
 741           increased overhead in some places. If unsure say N here.
 742
 743 config IRQ_TIME_ACCOUNTING
 744         bool "Fine granularity task level IRQ time accounting"
 745         default n
 746         ---help---
 747           Select this option to enable fine granularity task irq time
 748           accounting. This is done by reading a timestamp on each
 749           transitions between softirq and hardirq state, so there can be a
 750           small performance impact.
 751
 752           If in doubt, say N here.
 753
 754 source "kernel/Kconfig.preempt"
 755
 756 config X86_UP_APIC
 757         bool "Local APIC support on uniprocessors"
 758         depends on X86_32 && !SMP && !X86_32_NON_STANDARD
 759         ---help---
 760           A local APIC (Advanced Programmable Interrupt Controller) is an
 761           integrated interrupt controller in the CPU. If you have a single-CPU
 762           system which has a processor with a local APIC, you can say Y here to
 763           enable and use it. If you say Y here even though your machine doesn't
 764           have a local APIC, then the kernel will still run with no slowdown at
 765           all. The local APIC supports CPU-generated self-interrupts (timer,
 766           performance counters), and the NMI watchdog which detects hard
 767           lockups.
 768
 769 config X86_UP_IOAPIC
 770         bool "IO-APIC support on uniprocessors"
 771         depends on X86_UP_APIC
 772         ---help---
 773           An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
 774           SMP-capable replacement for PC-style interrupt controllers. Most
 775           SMP systems and many recent uniprocessor systems have one.
 776
 777           If you have a single-CPU system with an IO-APIC, you can say Y here
 778           to use it. If you say Y here even though your machine doesn't have
 779           an IO-APIC, then the kernel will still run with no slowdown at all.
 780
 781 config X86_LOCAL_APIC
 782         def_bool y
 783         depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
 784
 785 config X86_IO_APIC
 786         def_bool y
 787         depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
 788
 789 config X86_VISWS_APIC
 790         def_bool y
 791         depends on X86_32 && X86_VISWS
 792
 793 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
 794         bool "Reroute for broken boot IRQs"
 795         depends on X86_IO_APIC
 796         ---help---
 797           This option enables a workaround that fixes a source of
 798           spurious interrupts. This is recommended when threaded
 799           interrupt handling is used on systems where the generation of
 800           superfluous "boot interrupts" cannot be disabled.
 801
 802           Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
 803           entry in the chipset's IO-APIC is masked (as, e.g. the RT
 804           kernel does during interrupt handling). On chipsets where this
 805           boot IRQ generation cannot be disabled, this workaround keeps
 806           the original IRQ line masked so that only the equivalent "boot
 807           IRQ" is delivered to the CPUs. The workaround also tells the
 808           kernel to set up the IRQ handler on the boot IRQ line. In this
 809           way only one interrupt is delivered to the kernel. Otherwise
 810           the spurious second interrupt may cause the kernel to bring
 811           down (vital) interrupt lines.
 812
 813           Only affects "broken" chipsets. Interrupt sharing may be
 814           increased on these systems.
 815
 816 config X86_MCE
 817         bool "Machine Check / overheating reporting"
 818         ---help---
 819           Machine Check support allows the processor to notify the
 820           kernel if it detects a problem (e.g. overheating, data corruption).
 821           The action the kernel takes depends on the severity of the problem,
 822           ranging from warning messages to halting the machine.
 823
 824 config X86_MCE_INTEL
 825         def_bool y
 826         prompt "Intel MCE features"
 827         depends on X86_MCE && X86_LOCAL_APIC
 828         ---help---
 829            Additional support for intel specific MCE features such as
 830            the thermal monitor.
 831
 832 config X86_MCE_AMD
 833         def_bool y
 834         prompt "AMD MCE features"
 835         depends on X86_MCE && X86_LOCAL_APIC
 836         ---help---
 837            Additional support for AMD specific MCE features such as
 838            the DRAM Error Threshold.
 839
 840 config X86_ANCIENT_MCE
 841         bool "Support for old Pentium 5 / WinChip machine checks"
 842         depends on X86_32 && X86_MCE
 843         ---help---
 844           Include support for machine check handling on old Pentium 5 or WinChip
 845           systems. These typically need to be enabled explicitely on the command
 846           line.
 847
 848 config X86_MCE_THRESHOLD
 849         depends on X86_MCE_AMD || X86_MCE_INTEL
 850         def_bool y
 851
 852 config X86_MCE_INJECT
 853         depends on X86_MCE
 854         tristate "Machine check injector support"
 855         ---help---
 856           Provide support for injecting machine checks for testing purposes.
 857           If you don't know what a machine check is and you don't do kernel
 858           QA it is safe to say n.
 859
 860 config X86_THERMAL_VECTOR
 861         def_bool y
 862         depends on X86_MCE_INTEL
 863
 864 config VM86
 865         bool "Enable VM86 support" if EMBEDDED
 866         default y
 867         depends on X86_32
 868         ---help---
 869           This option is required by programs like DOSEMU to run 16-bit legacy
 870           code on X86 processors. It also may be needed by software like
 871           XFree86 to initialize some video cards via BIOS. Disabling this
 872           option saves about 6k.
 873
 874 config TOSHIBA
 875         tristate "Toshiba Laptop support"
 876         depends on X86_32
 877         ---help---
 878           This adds a driver to safely access the System Management Mode of
 879           the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
 880           not work on models with a Phoenix BIOS. The System Management Mode
 881           is used to set the BIOS and power saving options on Toshiba portables.
 882
 883           For information on utilities to make use of this driver see the
 884           Toshiba Linux utilities web site at:
 885           <http://www.buzzard.org.uk/toshiba/>.
 886
 887           Say Y if you intend to run this kernel on a Toshiba portable.
 888           Say N otherwise.
 889
 890 config I8K
 891         tristate "Dell laptop support"
 892         ---help---
 893           This adds a driver to safely access the System Management Mode
 894           of the CPU on the Dell Inspiron 8000. The System Management Mode
 895           is used to read cpu temperature and cooling fan status and to
 896           control the fans on the I8K portables.
 897
 898           This driver has been tested only on the Inspiron 8000 but it may
 899           also work with other Dell laptops. You can force loading on other
 900           models by passing the parameter `force=1' to the module. Use at
 901           your own risk.
 902
 903           For information on utilities to make use of this driver see the
 904           I8K Linux utilities web site at:
 905           <http://people.debian.org/~dz/i8k/>
 906
 907           Say Y if you intend to run this kernel on a Dell Inspiron 8000.
 908           Say N otherwise.
 909
 910 config X86_REBOOTFIXUPS
 911         bool "Enable X86 board specific fixups for reboot"
 912         depends on X86_32
 913         ---help---
 914           This enables chipset and/or board specific fixups to be done
 915           in order to get reboot to work correctly. This is only needed on
 916           some combinations of hardware and BIOS. The symptom, for which
 917           this config is intended, is when reboot ends with a stalled/hung
 918           system.
 919
 920           Currently, the only fixup is for the Geode machines using
 921           CS5530A and CS5536 chipsets and the RDC R-321x SoC.
 922
 923           Say Y if you want to enable the fixup. Currently, it's safe to
 924           enable this option even if you don't need it.
 925           Say N otherwise.
 926
 927 config MICROCODE
 928         tristate "/dev/cpu/microcode - microcode support"
 929         select FW_LOADER
 930         ---help---
 931           If you say Y here, you will be able to update the microcode on
 932           certain Intel and AMD processors. The Intel support is for the
 933           IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
 934           Pentium 4, Xeon etc. The AMD support is for family 0x10 and
 935           0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
 936           You will obviously need the actual microcode binary data itself
 937           which is not shipped with the Linux kernel.
 938
 939           This option selects the general module only, you need to select
 940           at least one vendor specific module as well.
 941
 942           To compile this driver as a module, choose M here: the
 943           module will be called microcode.
 944
 945 config MICROCODE_INTEL
 946         bool "Intel microcode patch loading support"
 947         depends on MICROCODE
 948         default MICROCODE
 949         select FW_LOADER
 950         ---help---
 951           This options enables microcode patch loading support for Intel
 952           processors.
 953
 954           For latest news and information on obtaining all the required
 955           Intel ingredients for this driver, check:
 956           <http://www.urbanmyth.org/microcode/>.
 957
 958 config MICROCODE_AMD
 959         bool "AMD microcode patch loading support"
 960         depends on MICROCODE
 961         select FW_LOADER
 962         ---help---
 963           If you select this option, microcode patch loading support for AMD
 964           processors will be enabled.
 965
 966 config MICROCODE_OLD_INTERFACE
 967         def_bool y
 968         depends on MICROCODE
 969
 970 config X86_MSR
 971         tristate "/dev/cpu/*/msr - Model-specific register support"
 972         ---help---
 973           This device gives privileged processes access to the x86
 974           Model-Specific Registers (MSRs).  It is a character device with
 975           major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
 976           MSR accesses are directed to a specific CPU on multi-processor
 977           systems.
 978
 979 config X86_CPUID
 980         tristate "/dev/cpu/*/cpuid - CPU information support"
 981         ---help---
 982           This device gives processes access to the x86 CPUID instruction to
 983           be executed on a specific processor.  It is a character device
 984           with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
 985           /dev/cpu/31/cpuid.
 986
 987 choice
 988         prompt "High Memory Support"
 989         default HIGHMEM64G if X86_NUMAQ
 990         default HIGHMEM4G
 991         depends on X86_32
 992
 993 config NOHIGHMEM
 994         bool "off"
 995         depends on !X86_NUMAQ
 996         ---help---
 997           Linux can use up to 64 Gigabytes of physical memory on x86 systems.
 998           However, the address space of 32-bit x86 processors is only 4
 999           Gigabytes large. That means that, if you have a large amount of
1000           physical memory, not all of it can be "permanently mapped" by the
1001           kernel. The physical memory that's not permanently mapped is called
1002           "high memory".
1003
1004           If you are compiling a kernel which will never run on a machine with
1005           more than 1 Gigabyte total physical RAM, answer "off" here (default
1006           choice and suitable for most users). This will result in a "3GB/1GB"
1007           split: 3GB are mapped so that each process sees a 3GB virtual memory
1008           space and the remaining part of the 4GB virtual memory space is used
1009           by the kernel to permanently map as much physical memory as
1010           possible.
1011
1012           If the machine has between 1 and 4 Gigabytes physical RAM, then
1013           answer "4GB" here.
1014
1015           If more than 4 Gigabytes is used then answer "64GB" here. This
1016           selection turns Intel PAE (Physical Address Extension) mode on.
1017           PAE implements 3-level paging on IA32 processors. PAE is fully
1018           supported by Linux, PAE mode is implemented on all recent Intel
1019           processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1020           then the kernel will not boot on CPUs that don't support PAE!
1021
1022           The actual amount of total physical memory will either be
1023           auto detected or can be forced by using a kernel command line option
1024           such as "mem=256M". (Try "man bootparam" or see the documentation of
1025           your boot loader (lilo or loadlin) about how to pass options to the
1026           kernel at boot time.)
1027
1028           If unsure, say "off".
1029
1030 config HIGHMEM4G
1031         bool "4GB"
1032         depends on !X86_NUMAQ
1033         ---help---
1034           Select this if you have a 32-bit processor and between 1 and 4
1035           gigabytes of physical RAM.
1036
1037 config HIGHMEM64G
1038         bool "64GB"
1039         depends on !M386 && !M486
1040         select X86_PAE
1041         ---help---
1042           Select this if you have a 32-bit processor and more than 4
1043           gigabytes of physical RAM.
1044
1045 endchoice
1046
1047 choice
1048         depends on EXPERIMENTAL
1049         prompt "Memory split" if EMBEDDED
1050         default VMSPLIT_3G
1051         depends on X86_32
1052         ---help---
1053           Select the desired split between kernel and user memory.
1054
1055           If the address range available to the kernel is less than the
1056           physical memory installed, the remaining memory will be available
1057           as "high memory". Accessing high memory is a little more costly
1058           than low memory, as it needs to be mapped into the kernel first.
1059           Note that increasing the kernel address space limits the range
1060           available to user programs, making the address space there
1061           tighter.  Selecting anything other than the default 3G/1G split
1062           will also likely make your kernel incompatible with binary-only
1063           kernel modules.
1064
1065           If you are not absolutely sure what you are doing, leave this
1066           option alone!
1067
1068         config VMSPLIT_3G
1069                 bool "3G/1G user/kernel split"
1070         config VMSPLIT_3G_OPT
1071                 depends on !X86_PAE
1072                 bool "3G/1G user/kernel split (for full 1G low memory)"
1073         config VMSPLIT_2G
1074                 bool "2G/2G user/kernel split"
1075         config VMSPLIT_2G_OPT
1076                 depends on !X86_PAE
1077                 bool "2G/2G user/kernel split (for full 2G low memory)"
1078         config VMSPLIT_1G
1079                 bool "1G/3G user/kernel split"
1080 endchoice
1081
1082 config PAGE_OFFSET
1083         hex
1084         default 0xB0000000 if VMSPLIT_3G_OPT
1085         default 0x80000000 if VMSPLIT_2G
1086         default 0x78000000 if VMSPLIT_2G_OPT
1087         default 0x40000000 if VMSPLIT_1G
1088         default 0xC0000000
1089         depends on X86_32
1090
1091 config HIGHMEM
1092         def_bool y
1093         depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1094
1095 config X86_PAE
1096         bool "PAE (Physical Address Extension) Support"
1097         depends on X86_32 && !HIGHMEM4G
1098         ---help---
1099           PAE is required for NX support, and furthermore enables
1100           larger swapspace support for non-overcommit purposes. It
1101           has the cost of more pagetable lookup overhead, and also
1102           consumes more pagetable space per process.
1103
1104 config ARCH_PHYS_ADDR_T_64BIT
1105         def_bool X86_64 || X86_PAE
1106
1107 config ARCH_DMA_ADDR_T_64BIT
1108         def_bool X86_64 || HIGHMEM64G
1109
1110 config DIRECT_GBPAGES
1111         bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
1112         default y
1113         depends on X86_64
1114         ---help---
1115           Allow the kernel linear mapping to use 1GB pages on CPUs that
1116           support it. This can improve the kernel's performance a tiny bit by
1117           reducing TLB pressure. If in doubt, say "Y".
1118
1119 # Common NUMA Features
1120 config NUMA
1121         bool "Numa Memory Allocation and Scheduler Support"
1122         depends on SMP
1123         depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1124         default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1125         ---help---
1126           Enable NUMA (Non Uniform Memory Access) support.
1127
1128           The kernel will try to allocate memory used by a CPU on the
1129           local memory controller of the CPU and add some more
1130           NUMA awareness to the kernel.
1131
1132           For 64-bit this is recommended if the system is Intel Core i7
1133           (or later), AMD Opteron, or EM64T NUMA.
1134
1135           For 32-bit this is only needed on (rare) 32-bit-only platforms
1136           that support NUMA topologies, such as NUMAQ / Summit, or if you
1137           boot a 32-bit kernel on a 64-bit NUMA platform.
1138
1139           Otherwise, you should say N.
1140
1141 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1142         depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1143
1144 config K8_NUMA
1145         def_bool y
1146         prompt "Old style AMD Opteron NUMA detection"
1147         depends on X86_64 && NUMA && PCI
1148         ---help---
1149           Enable K8 NUMA node topology detection.  You should say Y here if
1150           you have a multi processor AMD K8 system. This uses an old
1151           method to read the NUMA configuration directly from the builtin
1152           Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
1153           instead, which also takes priority if both are compiled in.
1154
1155 config X86_64_ACPI_NUMA
1156         def_bool y
1157         prompt "ACPI NUMA detection"
1158         depends on X86_64 && NUMA && ACPI && PCI
1159         select ACPI_NUMA
1160         ---help---
1161           Enable ACPI SRAT based node topology detection.
1162
1163 # Some NUMA nodes have memory ranges that span
1164 # other nodes.  Even though a pfn is valid and
1165 # between a node's start and end pfns, it may not
1166 # reside on that node.  See memmap_init_zone()
1167 # for details.
1168 config NODES_SPAN_OTHER_NODES
1169         def_bool y
1170         depends on X86_64_ACPI_NUMA
1171
1172 config NUMA_EMU
1173         bool "NUMA emulation"
1174         depends on X86_64 && NUMA
1175         ---help---
1176           Enable NUMA emulation. A flat machine will be split
1177           into virtual nodes when booted with "numa=fake=N", where N is the
1178           number of nodes. This is only useful for debugging.
1179
1180 config NODES_SHIFT
1181         int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1182         range 1 10
1183         default "10" if MAXSMP
1184         default "6" if X86_64
1185         default "4" if X86_NUMAQ
1186         default "3"
1187         depends on NEED_MULTIPLE_NODES
1188         ---help---
1189           Specify the maximum number of NUMA Nodes available on the target
1190           system.  Increases memory reserved to accommodate various tables.
1191
1192 config HAVE_ARCH_BOOTMEM
1193         def_bool y
1194         depends on X86_32 && NUMA
1195
1196 config ARCH_HAVE_MEMORY_PRESENT
1197         def_bool y
1198         depends on X86_32 && DISCONTIGMEM
1199
1200 config NEED_NODE_MEMMAP_SIZE
1201         def_bool y
1202         depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1203
1204 config HAVE_ARCH_ALLOC_REMAP
1205         def_bool y
1206         depends on X86_32 && NUMA
1207
1208 config ARCH_FLATMEM_ENABLE
1209         def_bool y
1210         depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
1211
1212 config ARCH_DISCONTIGMEM_ENABLE
1213         def_bool y
1214         depends on NUMA && X86_32
1215
1216 config ARCH_DISCONTIGMEM_DEFAULT
1217         def_bool y
1218         depends on NUMA && X86_32
1219
1220 config ARCH_PROC_KCORE_TEXT
1221         def_bool y
1222         depends on X86_64 && PROC_KCORE
1223
1224 config ARCH_SPARSEMEM_DEFAULT
1225         def_bool y
1226         depends on X86_64
1227
1228 config ARCH_SPARSEMEM_ENABLE
1229         def_bool y
1230         depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1231         select SPARSEMEM_STATIC if X86_32
1232         select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1233
1234 config ARCH_SELECT_MEMORY_MODEL
1235         def_bool y
1236         depends on ARCH_SPARSEMEM_ENABLE
1237
1238 config ARCH_MEMORY_PROBE
1239         def_bool X86_64
1240         depends on MEMORY_HOTPLUG
1241
1242 config ILLEGAL_POINTER_VALUE
1243        hex
1244        default 0 if X86_32
1245        default 0xdead000000000000 if X86_64
1246
1247 source "mm/Kconfig"
1248
1249 config HIGHPTE
1250         bool "Allocate 3rd-level pagetables from highmem"
1251         depends on HIGHMEM
1252         ---help---
1253           The VM uses one page table entry for each page of physical memory.
1254           For systems with a lot of RAM, this can be wasteful of precious
1255           low memory.  Setting this option will put user-space page table
1256           entries in high memory.
1257
1258 config X86_CHECK_BIOS_CORRUPTION
1259         bool "Check for low memory corruption"
1260         ---help---
1261           Periodically check for memory corruption in low memory, which
1262           is suspected to be caused by BIOS.  Even when enabled in the
1263           configuration, it is disabled at runtime.  Enable it by
1264           setting "memory_corruption_check=1" on the kernel command
1265           line.  By default it scans the low 64k of memory every 60
1266           seconds; see the memory_corruption_check_size and
1267           memory_corruption_check_period parameters in
1268           Documentation/kernel-parameters.txt to adjust this.
1269
1270           When enabled with the default parameters, this option has
1271           almost no overhead, as it reserves a relatively small amount
1272           of memory and scans it infrequently.  It both detects corruption
1273           and prevents it from affecting the running system.
1274
1275           It is, however, intended as a diagnostic tool; if repeatable
1276           BIOS-originated corruption always affects the same memory,
1277           you can use memmap= to prevent the kernel from using that
1278           memory.
1279
1280 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1281         bool "Set the default setting of memory_corruption_check"
1282         depends on X86_CHECK_BIOS_CORRUPTION
1283         default y
1284         ---help---
1285           Set whether the default state of memory_corruption_check is
1286           on or off.
1287
1288 config X86_RESERVE_LOW
1289         int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1290         default 64
1291         range 4 640
1292         ---help---
1293           Specify the amount of low memory to reserve for the BIOS.
1294
1295           The first page contains BIOS data structures that the kernel
1296           must not use, so that page must always be reserved.
1297
1298           By default we reserve the first 64K of physical RAM, as a
1299           number of BIOSes are known to corrupt that memory range
1300           during events such as suspend/resume or monitor cable
1301           insertion, so it must not be used by the kernel.
1302
1303           You can set this to 4 if you are absolutely sure that you
1304           trust the BIOS to get all its memory reservations and usages
1305           right.  If you know your BIOS have problems beyond the
1306           default 64K area, you can set this to 640 to avoid using the
1307           entire low memory range.
1308
1309           If you have doubts about the BIOS (e.g. suspend/resume does
1310           not work or there's kernel crashes after certain hardware
1311           hotplug events) then you might want to enable
1312           X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1313           typical corruption patterns.
1314
1315           Leave this to the default value of 64 if you are unsure.
1316
1317 config MATH_EMULATION
1318         bool
1319         prompt "Math emulation" if X86_32
1320         ---help---
1321           Linux can emulate a math coprocessor (used for floating point
1322           operations) if you don't have one. 486DX and Pentium processors have
1323           a math coprocessor built in, 486SX and 386 do not, unless you added
1324           a 487DX or 387, respectively. (The messages during boot time can
1325           give you some hints here ["man dmesg"].) Everyone needs either a
1326           coprocessor or this emulation.
1327
1328           If you don't have a math coprocessor, you need to say Y here; if you
1329           say Y here even though you have a coprocessor, the coprocessor will
1330           be used nevertheless. (This behavior can be changed with the kernel
1331           command line option "no387", which comes handy if your coprocessor
1332           is broken. Try "man bootparam" or see the documentation of your boot
1333           loader (lilo or loadlin) about how to pass options to the kernel at
1334           boot time.) This means that it is a good idea to say Y here if you
1335           intend to use this kernel on different machines.
1336
1337           More information about the internals of the Linux math coprocessor
1338           emulation can be found in <file:arch/x86/math-emu/README>.
1339
1340           If you are not sure, say Y; apart from resulting in a 66 KB bigger
1341           kernel, it won't hurt.
1342
1343 config MTRR
1344         def_bool y
1345         prompt "MTRR (Memory Type Range Register) support" if EMBEDDED
1346         ---help---
1347           On Intel P6 family processors (Pentium Pro, Pentium II and later)
1348           the Memory Type Range Registers (MTRRs) may be used to control
1349           processor access to memory ranges. This is most useful if you have
1350           a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1351           allows bus write transfers to be combined into a larger transfer
1352           before bursting over the PCI/AGP bus. This can increase performance
1353           of image write operations 2.5 times or more. Saying Y here creates a
1354           /proc/mtrr file which may be used to manipulate your processor's
1355           MTRRs. Typically the X server should use this.
1356
1357           This code has a reasonably generic interface so that similar
1358           control registers on other processors can be easily supported
1359           as well:
1360
1361           The Cyrix 6x86, 6x86MX and M II processors have Address Range
1362           Registers (ARRs) which provide a similar functionality to MTRRs. For
1363           these, the ARRs are used to emulate the MTRRs.
1364           The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1365           MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1366           write-combining. All of these processors are supported by this code
1367           and it makes sense to say Y here if you have one of them.
1368
1369           Saying Y here also fixes a problem with buggy SMP BIOSes which only
1370           set the MTRRs for the boot CPU and not for the secondary CPUs. This
1371           can lead to all sorts of problems, so it's good to say Y here.
1372
1373           You can safely say Y even if your machine doesn't have MTRRs, you'll
1374           just add about 9 KB to your kernel.
1375
1376           See <file:Documentation/x86/mtrr.txt> for more information.
1377
1378 config MTRR_SANITIZER
1379         def_bool y
1380         prompt "MTRR cleanup support"
1381         depends on MTRR
1382         ---help---
1383           Convert MTRR layout from continuous to discrete, so X drivers can
1384           add writeback entries.
1385
1386           Can be disabled with disable_mtrr_cleanup on the kernel command line.
1387           The largest mtrr entry size for a continuous block can be set with
1388           mtrr_chunk_size.
1389
1390           If unsure, say Y.
1391
1392 config MTRR_SANITIZER_ENABLE_DEFAULT
1393         int "MTRR cleanup enable value (0-1)"
1394         range 0 1
1395         default "0"
1396         depends on MTRR_SANITIZER
1397         ---help---
1398           Enable mtrr cleanup default value
1399
1400 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1401         int "MTRR cleanup spare reg num (0-7)"
1402         range 0 7
1403         default "1"
1404         depends on MTRR_SANITIZER
1405         ---help---
1406           mtrr cleanup spare entries default, it can be changed via
1407           mtrr_spare_reg_nr=N on the kernel command line.
1408
1409 config X86_PAT
1410         def_bool y
1411         prompt "x86 PAT support" if EMBEDDED
1412         depends on MTRR
1413         ---help---
1414           Use PAT attributes to setup page level cache control.
1415
1416           PATs are the modern equivalents of MTRRs and are much more
1417           flexible than MTRRs.
1418
1419           Say N here if you see bootup problems (boot crash, boot hang,
1420           spontaneous reboots) or a non-working video driver.
1421
1422           If unsure, say Y.
1423
1424 config ARCH_USES_PG_UNCACHED
1425         def_bool y
1426         depends on X86_PAT
1427
1428 config EFI
1429         bool "EFI runtime service support"
1430         depends on ACPI
1431         ---help---
1432           This enables the kernel to use EFI runtime services that are
1433           available (such as the EFI variable services).
1434
1435           This option is only useful on systems that have EFI firmware.
1436           In addition, you should use the latest ELILO loader available
1437           at <http://elilo.sourceforge.net> in order to take advantage
1438           of EFI runtime services. However, even with this option, the
1439           resultant kernel should continue to boot on existing non-EFI
1440           platforms.
1441
1442 config SECCOMP
1443         def_bool y
1444         prompt "Enable seccomp to safely compute untrusted bytecode"
1445         ---help---
1446           This kernel feature is useful for number crunching applications
1447           that may need to compute untrusted bytecode during their
1448           execution. By using pipes or other transports made available to
1449           the process as file descriptors supporting the read/write
1450           syscalls, it's possible to isolate those applications in
1451           their own address space using seccomp. Once seccomp is
1452           enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1453           and the task is only allowed to execute a few safe syscalls
1454           defined by each seccomp mode.
1455
1456           If unsure, say Y. Only embedded should say N here.
1457
1458 config CC_STACKPROTECTOR
1459         bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1460         ---help---
1461           This option turns on the -fstack-protector GCC feature. This
1462           feature puts, at the beginning of functions, a canary value on
1463           the stack just before the return address, and validates
1464           the value just before actually returning.  Stack based buffer
1465           overflows (that need to overwrite this return address) now also
1466           overwrite the canary, which gets detected and the attack is then
1467           neutralized via a kernel panic.
1468
1469           This feature requires gcc version 4.2 or above, or a distribution
1470           gcc with the feature backported. Older versions are automatically
1471           detected and for those versions, this configuration option is
1472           ignored. (and a warning is printed during bootup)
1473
1474 source kernel/Kconfig.hz
1475
1476 config KEXEC
1477         bool "kexec system call"
1478         ---help---
1479           kexec is a system call that implements the ability to shutdown your
1480           current kernel, and to start another kernel.  It is like a reboot
1481           but it is independent of the system firmware.   And like a reboot
1482           you can start any kernel with it, not just Linux.
1483
1484           The name comes from the similarity to the exec system call.
1485
1486           It is an ongoing process to be certain the hardware in a machine
1487           is properly shutdown, so do not be surprised if this code does not
1488           initially work for you.  It may help to enable device hotplugging
1489           support.  As of this writing the exact hardware interface is
1490           strongly in flux, so no good recommendation can be made.
1491
1492 config CRASH_DUMP
1493         bool "kernel crash dumps"
1494         depends on X86_64 || (X86_32 && HIGHMEM)
1495         ---help---
1496           Generate crash dump after being started by kexec.
1497           This should be normally only set in special crash dump kernels
1498           which are loaded in the main kernel with kexec-tools into
1499           a specially reserved region and then later executed after
1500           a crash by kdump/kexec. The crash dump kernel must be compiled
1501           to a memory address not used by the main kernel or BIOS using
1502           PHYSICAL_START, or it must be built as a relocatable image
1503           (CONFIG_RELOCATABLE=y).
1504           For more details see Documentation/kdump/kdump.txt
1505
1506 config KEXEC_JUMP
1507         bool "kexec jump (EXPERIMENTAL)"
1508         depends on EXPERIMENTAL
1509         depends on KEXEC && HIBERNATION
1510         ---help---
1511           Jump between original kernel and kexeced kernel and invoke
1512           code in physical address mode via KEXEC
1513
1514 config PHYSICAL_START
1515         hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1516         default "0x1000000"
1517         ---help---
1518           This gives the physical address where the kernel is loaded.
1519
1520           If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1521           bzImage will decompress itself to above physical address and
1522           run from there. Otherwise, bzImage will run from the address where
1523           it has been loaded by the boot loader and will ignore above physical
1524           address.
1525
1526           In normal kdump cases one does not have to set/change this option
1527           as now bzImage can be compiled as a completely relocatable image
1528           (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1529           address. This option is mainly useful for the folks who don't want
1530           to use a bzImage for capturing the crash dump and want to use a
1531           vmlinux instead. vmlinux is not relocatable hence a kernel needs
1532           to be specifically compiled to run from a specific memory area
1533           (normally a reserved region) and this option comes handy.
1534
1535           So if you are using bzImage for capturing the crash dump,
1536           leave the value here unchanged to 0x1000000 and set
1537           CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
1538           for capturing the crash dump change this value to start of
1539           the reserved region.  In other words, it can be set based on
1540           the "X" value as specified in the "crashkernel=YM@XM"
1541           command line boot parameter passed to the panic-ed
1542           kernel. Please take a look at Documentation/kdump/kdump.txt
1543           for more details about crash dumps.
1544
1545           Usage of bzImage for capturing the crash dump is recommended as
1546           one does not have to build two kernels. Same kernel can be used
1547           as production kernel and capture kernel. Above option should have
1548           gone away after relocatable bzImage support is introduced. But it
1549           is present because there are users out there who continue to use
1550           vmlinux for dump capture. This option should go away down the
1551           line.
1552
1553           Don't change this unless you know what you are doing.
1554
1555 config RELOCATABLE
1556         bool "Build a relocatable kernel"
1557         default y
1558         ---help---
1559           This builds a kernel image that retains relocation information
1560           so it can be loaded someplace besides the default 1MB.
1561           The relocations tend to make the kernel binary about 10% larger,
1562           but are discarded at runtime.
1563
1564           One use is for the kexec on panic case where the recovery kernel
1565           must live at a different physical address than the primary
1566           kernel.
1567
1568           Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1569           it has been loaded at and the compile time physical address
1570           (CONFIG_PHYSICAL_START) is ignored.
1571
1572 # Relocation on x86-32 needs some additional build support
1573 config X86_NEED_RELOCS
1574         def_bool y
1575         depends on X86_32 && RELOCATABLE
1576
1577 config PHYSICAL_ALIGN
1578         hex "Alignment value to which kernel should be aligned" if X86_32
1579         default "0x1000000"
1580         range 0x2000 0x1000000
1581         ---help---
1582           This value puts the alignment restrictions on physical address
1583           where kernel is loaded and run from. Kernel is compiled for an
1584           address which meets above alignment restriction.
1585
1586           If bootloader loads the kernel at a non-aligned address and
1587           CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1588           address aligned to above value and run from there.
1589
1590           If bootloader loads the kernel at a non-aligned address and
1591           CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1592           load address and decompress itself to the address it has been
1593           compiled for and run from there. The address for which kernel is
1594           compiled already meets above alignment restrictions. Hence the
1595           end result is that kernel runs from a physical address meeting
1596           above alignment restrictions.
1597
1598           Don't change this unless you know what you are doing.
1599
1600 config HOTPLUG_CPU
1601         bool "Support for hot-pluggable CPUs"
1602         depends on SMP && HOTPLUG
1603         ---help---
1604           Say Y here to allow turning CPUs off and on. CPUs can be
1605           controlled through /sys/devices/system/cpu.
1606           ( Note: power management support will enable this option
1607             automatically on SMP systems. )
1608           Say N if you want to disable CPU hotplug.
1609
1610 config COMPAT_VDSO
1611         def_bool y
1612         prompt "Compat VDSO support"
1613         depends on X86_32 || IA32_EMULATION
1614         ---help---
1615           Map the 32-bit VDSO to the predictable old-style address too.
1616
1617           Say N here if you are running a sufficiently recent glibc
1618           version (2.3.3 or later), to remove the high-mapped
1619           VDSO mapping and to exclusively use the randomized VDSO.
1620
1621           If unsure, say Y.
1622
1623 config CMDLINE_BOOL
1624         bool "Built-in kernel command line"
1625         ---help---
1626           Allow for specifying boot arguments to the kernel at
1627           build time.  On some systems (e.g. embedded ones), it is
1628           necessary or convenient to provide some or all of the
1629           kernel boot arguments with the kernel itself (that is,
1630           to not rely on the boot loader to provide them.)
1631
1632           To compile command line arguments into the kernel,
1633           set this option to 'Y', then fill in the
1634           the boot arguments in CONFIG_CMDLINE.
1635
1636           Systems with fully functional boot loaders (i.e. non-embedded)
1637           should leave this option set to 'N'.
1638
1639 config CMDLINE
1640         string "Built-in kernel command string"
1641         depends on CMDLINE_BOOL
1642         default ""
1643         ---help---
1644           Enter arguments here that should be compiled into the kernel
1645           image and used at boot time.  If the boot loader provides a
1646           command line at boot time, it is appended to this string to
1647           form the full kernel command line, when the system boots.
1648
1649           However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1650           change this behavior.
1651
1652           In most cases, the command line (whether built-in or provided
1653           by the boot loader) should specify the device for the root
1654           file system.
1655
1656 config CMDLINE_OVERRIDE
1657         bool "Built-in command line overrides boot loader arguments"
1658         depends on CMDLINE_BOOL
1659         ---help---
1660           Set this option to 'Y' to have the kernel ignore the boot loader
1661           command line, and use ONLY the built-in command line.
1662
1663           This is used to work around broken boot loaders.  This should
1664           be set to 'N' under normal conditions.
1665
1666 endmenu
1667
1668 config ARCH_ENABLE_MEMORY_HOTPLUG
1669         def_bool y
1670         depends on X86_64 || (X86_32 && HIGHMEM)
1671
1672 config ARCH_ENABLE_MEMORY_HOTREMOVE
1673         def_bool y
1674         depends on MEMORY_HOTPLUG
1675
1676 config HAVE_ARCH_EARLY_PFN_TO_NID
1677         def_bool X86_64
1678         depends on NUMA
1679
1680 config USE_PERCPU_NUMA_NODE_ID
1681         def_bool X86_64
1682         depends on NUMA
1683
1684 menu "Power management and ACPI options"
1685
1686 config ARCH_HIBERNATION_HEADER
1687         def_bool y
1688         depends on X86_64 && HIBERNATION
1689
1690 source "kernel/power/Kconfig"
1691
1692 source "drivers/acpi/Kconfig"
1693
1694 source "drivers/sfi/Kconfig"
1695
1696 config X86_APM_BOOT
1697         def_bool y
1698         depends on APM || APM_MODULE
1699
1700 menuconfig APM
1701         tristate "APM (Advanced Power Management) BIOS support"
1702         depends on X86_32 && PM_SLEEP
1703         ---help---
1704           APM is a BIOS specification for saving power using several different
1705           techniques. This is mostly useful for battery powered laptops with
1706           APM compliant BIOSes. If you say Y here, the system time will be
1707           reset after a RESUME operation, the /proc/apm device will provide
1708           battery status information, and user-space programs will receive
1709           notification of APM "events" (e.g. battery status change).
1710
1711           If you select "Y" here, you can disable actual use of the APM
1712           BIOS by passing the "apm=off" option to the kernel at boot time.
1713
1714           Note that the APM support is almost completely disabled for
1715           machines with more than one CPU.
1716
1717           In order to use APM, you will need supporting software. For location
1718           and more information, read <file:Documentation/power/pm.txt> and the
1719           Battery Powered Linux mini-HOWTO, available from
1720           <http://www.tldp.org/docs.html#howto>.
1721
1722           This driver does not spin down disk drives (see the hdparm(8)
1723           manpage ("man 8 hdparm") for that), and it doesn't turn off
1724           VESA-compliant "green" monitors.
1725
1726           This driver does not support the TI 4000M TravelMate and the ACER
1727           486/DX4/75 because they don't have compliant BIOSes. Many "green"
1728           desktop machines also don't have compliant BIOSes, and this driver
1729           may cause those machines to panic during the boot phase.
1730
1731           Generally, if you don't have a battery in your machine, there isn't
1732           much point in using this driver and you should say N. If you get
1733           random kernel OOPSes or reboots that don't seem to be related to
1734           anything, try disabling/enabling this option (or disabling/enabling
1735           APM in your BIOS).
1736
1737           Some other things you should try when experiencing seemingly random,
1738           "weird" problems:
1739
1740           1) make sure that you have enough swap space and that it is
1741           enabled.
1742           2) pass the "no-hlt" option to the kernel
1743           3) switch on floating point emulation in the kernel and pass
1744           the "no387" option to the kernel
1745           4) pass the "floppy=nodma" option to the kernel
1746           5) pass the "mem=4M" option to the kernel (thereby disabling
1747           all but the first 4 MB of RAM)
1748           6) make sure that the CPU is not over clocked.
1749           7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1750           8) disable the cache from your BIOS settings
1751           9) install a fan for the video card or exchange video RAM
1752           10) install a better fan for the CPU
1753           11) exchange RAM chips
1754           12) exchange the motherboard.
1755
1756           To compile this driver as a module, choose M here: the
1757           module will be called apm.
1758
1759 if APM
1760
1761 config APM_IGNORE_USER_SUSPEND
1762         bool "Ignore USER SUSPEND"
1763         ---help---
1764           This option will ignore USER SUSPEND requests. On machines with a
1765           compliant APM BIOS, you want to say N. However, on the NEC Versa M
1766           series notebooks, it is necessary to say Y because of a BIOS bug.
1767
1768 config APM_DO_ENABLE
1769         bool "Enable PM at boot time"
1770         ---help---
1771           Enable APM features at boot time. From page 36 of the APM BIOS
1772           specification: "When disabled, the APM BIOS does not automatically
1773           power manage devices, enter the Standby State, enter the Suspend
1774           State, or take power saving steps in response to CPU Idle calls."
1775           This driver will make CPU Idle calls when Linux is idle (unless this
1776           feature is turned off -- see "Do CPU IDLE calls", below). This
1777           should always save battery power, but more complicated APM features
1778           will be dependent on your BIOS implementation. You may need to turn
1779           this option off if your computer hangs at boot time when using APM
1780           support, or if it beeps continuously instead of suspending. Turn
1781           this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1782           T400CDT. This is off by default since most machines do fine without
1783           this feature.
1784
1785 config APM_CPU_IDLE
1786         bool "Make CPU Idle calls when idle"
1787         ---help---
1788           Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1789           On some machines, this can activate improved power savings, such as
1790           a slowed CPU clock rate, when the machine is idle. These idle calls
1791           are made after the idle loop has run for some length of time (e.g.,
1792           333 mS). On some machines, this will cause a hang at boot time or
1793           whenever the CPU becomes idle. (On machines with more than one CPU,
1794           this option does nothing.)
1795
1796 config APM_DISPLAY_BLANK
1797         bool "Enable console blanking using APM"
1798         ---help---
1799           Enable console blanking using the APM. Some laptops can use this to
1800           turn off the LCD backlight when the screen blanker of the Linux
1801           virtual console blanks the screen. Note that this is only used by
1802           the virtual console screen blanker, and won't turn off the backlight
1803           when using the X Window system. This also doesn't have anything to
1804           do with your VESA-compliant power-saving monitor. Further, this
1805           option doesn't work for all laptops -- it might not turn off your
1806           backlight at all, or it might print a lot of errors to the console,
1807           especially if you are using gpm.
1808
1809 config APM_ALLOW_INTS
1810         bool "Allow interrupts during APM BIOS calls"
1811         ---help---
1812           Normally we disable external interrupts while we are making calls to
1813           the APM BIOS as a measure to lessen the effects of a badly behaving
1814           BIOS implementation.  The BIOS should reenable interrupts if it
1815           needs to.  Unfortunately, some BIOSes do not -- especially those in
1816           many of the newer IBM Thinkpads.  If you experience hangs when you
1817           suspend, try setting this to Y.  Otherwise, say N.
1818
1819 endif # APM
1820
1821 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1822
1823 source "drivers/cpuidle/Kconfig"
1824
1825 source "drivers/idle/Kconfig"
1826
1827 endmenu
1828
1829
1830 menu "Bus options (PCI etc.)"
1831
1832 config PCI
1833         bool "PCI support"
1834         default y
1835         select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1836         ---help---
1837           Find out whether you have a PCI motherboard. PCI is the name of a
1838           bus system, i.e. the way the CPU talks to the other stuff inside
1839           your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1840           VESA. If you have PCI, say Y, otherwise N.
1841
1842 choice
1843         prompt "PCI access mode"
1844         depends on X86_32 && PCI
1845         default PCI_GOANY
1846         ---help---
1847           On PCI systems, the BIOS can be used to detect the PCI devices and
1848           determine their configuration. However, some old PCI motherboards
1849           have BIOS bugs and may crash if this is done. Also, some embedded
1850           PCI-based systems don't have any BIOS at all. Linux can also try to
1851           detect the PCI hardware directly without using the BIOS.
1852
1853           With this option, you can specify how Linux should detect the
1854           PCI devices. If you choose "BIOS", the BIOS will be used,
1855           if you choose "Direct", the BIOS won't be used, and if you
1856           choose "MMConfig", then PCI Express MMCONFIG will be used.
1857           If you choose "Any", the kernel will try MMCONFIG, then the
1858           direct access method and falls back to the BIOS if that doesn't
1859           work. If unsure, go with the default, which is "Any".
1860
1861 config PCI_GOBIOS
1862         bool "BIOS"
1863
1864 config PCI_GOMMCONFIG
1865         bool "MMConfig"
1866
1867 config PCI_GODIRECT
1868         bool "Direct"
1869
1870 config PCI_GOOLPC
1871         bool "OLPC XO-1"
1872         depends on OLPC
1873
1874 config PCI_GOANY
1875         bool "Any"
1876
1877 endchoice
1878
1879 config PCI_BIOS
1880         def_bool y
1881         depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1882
1883 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1884 config PCI_DIRECT
1885         def_bool y
1886         depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1887
1888 config PCI_MMCONFIG
1889         def_bool y
1890         depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
1891
1892 config PCI_OLPC
1893         def_bool y
1894         depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1895
1896 config PCI_XEN
1897         def_bool y
1898         depends on PCI && XEN
1899         select SWIOTLB_XEN
1900
1901 config PCI_DOMAINS
1902         def_bool y
1903         depends on PCI
1904
1905 config PCI_MMCONFIG
1906         bool "Support mmconfig PCI config space access"
1907         depends on X86_64 && PCI && ACPI
1908
1909 config PCI_CNB20LE_QUIRK
1910         bool "Read CNB20LE Host Bridge Windows"
1911         depends on PCI
1912         help
1913           Read the PCI windows out of the CNB20LE host bridge. This allows
1914           PCI hotplug to work on systems with the CNB20LE chipset which do
1915           not have ACPI.
1916
1917 config DMAR
1918         bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1919         depends on PCI_MSI && ACPI && EXPERIMENTAL
1920         help
1921           DMA remapping (DMAR) devices support enables independent address
1922           translations for Direct Memory Access (DMA) from devices.
1923           These DMA remapping devices are reported via ACPI tables
1924           and include PCI device scope covered by these DMA
1925           remapping devices.
1926
1927 config DMAR_DEFAULT_ON
1928         def_bool y
1929         prompt "Enable DMA Remapping Devices by default"
1930         depends on DMAR
1931         help
1932           Selecting this option will enable a DMAR device at boot time if
1933           one is found. If this option is not selected, DMAR support can
1934           be enabled by passing intel_iommu=on to the kernel. It is
1935           recommended you say N here while the DMAR code remains
1936           experimental.
1937
1938 config DMAR_BROKEN_GFX_WA
1939         bool "Workaround broken graphics drivers (going away soon)"
1940         depends on DMAR && BROKEN
1941         ---help---
1942           Current Graphics drivers tend to use physical address
1943           for DMA and avoid using DMA APIs. Setting this config
1944           option permits the IOMMU driver to set a unity map for
1945           all the OS-visible memory. Hence the driver can continue
1946           to use physical addresses for DMA, at least until this
1947           option is removed in the 2.6.32 kernel.
1948
1949 config DMAR_FLOPPY_WA
1950         def_bool y
1951         depends on DMAR
1952         ---help---
1953           Floppy disk drivers are known to bypass DMA API calls
1954           thereby failing to work when IOMMU is enabled. This
1955           workaround will setup a 1:1 mapping for the first
1956           16MiB to make floppy (an ISA device) work.
1957
1958 config INTR_REMAP
1959         bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1960         depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
1961         ---help---
1962           Supports Interrupt remapping for IO-APIC and MSI devices.
1963           To use x2apic mode in the CPU's which support x2APIC enhancements or
1964           to support platforms with CPU's having > 8 bit APIC ID, say Y.
1965
1966 source "drivers/pci/pcie/Kconfig"
1967
1968 source "drivers/pci/Kconfig"
1969
1970 # x86_64 have no ISA slots, but do have ISA-style DMA.
1971 config ISA_DMA_API
1972         def_bool y
1973
1974 if X86_32
1975
1976 config ISA
1977         bool "ISA support"
1978         ---help---
1979           Find out whether you have ISA slots on your motherboard.  ISA is the
1980           name of a bus system, i.e. the way the CPU talks to the other stuff
1981           inside your box.  Other bus systems are PCI, EISA, MicroChannel
1982           (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
1983           newer boards don't support it.  If you have ISA, say Y, otherwise N.
1984
1985 config EISA
1986         bool "EISA support"
1987         depends on ISA
1988         ---help---
1989           The Extended Industry Standard Architecture (EISA) bus was
1990           developed as an open alternative to the IBM MicroChannel bus.
1991
1992           The EISA bus provided some of the features of the IBM MicroChannel
1993           bus while maintaining backward compatibility with cards made for
1994           the older ISA bus.  The EISA bus saw limited use between 1988 and
1995           1995 when it was made obsolete by the PCI bus.
1996
1997           Say Y here if you are building a kernel for an EISA-based machine.
1998
1999           Otherwise, say N.
2000
2001 source "drivers/eisa/Kconfig"
2002
2003 config MCA
2004         bool "MCA support"
2005         ---help---
2006           MicroChannel Architecture is found in some IBM PS/2 machines and
2007           laptops.  It is a bus system similar to PCI or ISA. See
2008           <file:Documentation/mca.txt> (and especially the web page given
2009           there) before attempting to build an MCA bus kernel.
2010
2011 source "drivers/mca/Kconfig"
2012
2013 config SCx200
2014         tristate "NatSemi SCx200 support"
2015         ---help---
2016           This provides basic support for National Semiconductor's
2017           (now AMD's) Geode processors.  The driver probes for the
2018           PCI-IDs of several on-chip devices, so its a good dependency
2019           for other scx200_* drivers.
2020
2021           If compiled as a module, the driver is named scx200.
2022
2023 config SCx200HR_TIMER
2024         tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2025         depends on SCx200
2026         default y
2027         ---help---
2028           This driver provides a clocksource built upon the on-chip
2029           27MHz high-resolution timer.  Its also a workaround for
2030           NSC Geode SC-1100's buggy TSC, which loses time when the
2031           processor goes idle (as is done by the scheduler).  The
2032           other workaround is idle=poll boot option.
2033
2034 config OLPC
2035         bool "One Laptop Per Child support"
2036         select GPIOLIB
2037         select OLPC_OPENFIRMWARE
2038         ---help---
2039           Add support for detecting the unique features of the OLPC
2040           XO hardware.
2041
2042 config OLPC_XO1
2043         tristate "OLPC XO-1 support"
2044         depends on OLPC && PCI
2045         ---help---
2046           Add support for non-essential features of the OLPC XO-1 laptop.
2047
2048 config OLPC_OPENFIRMWARE
2049         bool "Support for OLPC's Open Firmware"
2050         depends on !X86_64 && !X86_PAE
2051         default n
2052         help
2053           This option adds support for the implementation of Open Firmware
2054           that is used on the OLPC XO-1 Children's Machine.
2055           If unsure, say N here.
2056
2057 endif # X86_32
2058
2059 config AMD_NB
2060         def_bool y
2061         depends on CPU_SUP_AMD && PCI
2062
2063 source "drivers/pcmcia/Kconfig"
2064
2065 source "drivers/pci/hotplug/Kconfig"
2066
2067 endmenu
2068
2069
2070 menu "Executable file formats / Emulations"
2071
2072 source "fs/Kconfig.binfmt"
2073
2074 config IA32_EMULATION
2075         bool "IA32 Emulation"
2076         depends on X86_64
2077         select COMPAT_BINFMT_ELF
2078         ---help---
2079           Include code to run 32-bit programs under a 64-bit kernel. You should
2080           likely turn this on, unless you're 100% sure that you don't have any
2081           32-bit programs left.
2082
2083 config IA32_AOUT
2084         tristate "IA32 a.out support"
2085         depends on IA32_EMULATION
2086         ---help---
2087           Support old a.out binaries in the 32bit emulation.
2088
2089 config COMPAT
2090         def_bool y
2091         depends on IA32_EMULATION
2092
2093 config COMPAT_FOR_U64_ALIGNMENT
2094         def_bool COMPAT
2095         depends on X86_64
2096
2097 config SYSVIPC_COMPAT
2098         def_bool y
2099         depends on COMPAT && SYSVIPC
2100
2101 endmenu
2102
2103
2104 config HAVE_ATOMIC_IOMAP
2105         def_bool y
2106         depends on X86_32
2107
2108 config HAVE_TEXT_POKE_SMP
2109         bool
2110         select STOP_MACHINE if SMP
2111
2112 source "net/Kconfig"
2113
2114 source "drivers/Kconfig"
2115
2116 source "drivers/firmware/Kconfig"
2117
2118 source "fs/Kconfig"
2119
2120 source "arch/x86/Kconfig.debug"
2121
2122 source "security/Kconfig"
2123
2124 source "crypto/Kconfig"
2125
2126 source "arch/x86/kvm/Kconfig"
2127
2128 source "lib/Kconfig"