arch/x86/Kconfig

   1 # x86 configuration
   2 mainmenu "Linux Kernel Configuration for x86"
   3
   4 # Select 32 or 64 bit
   5 config 64BIT
   6         bool "64-bit kernel" if ARCH = "x86"
   7         default ARCH = "x86_64"
   8         ---help---
   9           Say yes to build a 64-bit kernel - formerly known as x86_64
  10           Say no to build a 32-bit kernel - formerly known as i386
  11
  12 config X86_32
  13         def_bool !64BIT
  14
  15 config X86_64
  16         def_bool 64BIT
  17
  18 ### Arch settings
  19 config X86
  20         def_bool y
  21         select HAVE_AOUT if X86_32
  22         select HAVE_READQ
  23         select HAVE_WRITEQ
  24         select HAVE_UNSTABLE_SCHED_CLOCK
  25         select HAVE_IDE
  26         select HAVE_OPROFILE
  27         select HAVE_PERF_EVENTS if (!M386 && !M486)
  28         select HAVE_IOREMAP_PROT
  29         select HAVE_KPROBES
  30         select ARCH_WANT_OPTIONAL_GPIOLIB
  31         select ARCH_WANT_FRAME_POINTERS
  32         select HAVE_DMA_ATTRS
  33         select HAVE_KRETPROBES
  34         select HAVE_OPTPROBES
  35         select HAVE_FTRACE_MCOUNT_RECORD
  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 ANON_INODES
  59         select HAVE_ARCH_KMEMCHECK
  60         select HAVE_USER_RETURN_NOTIFIER
  61
  62 config INSTRUCTION_DECODER
  63         def_bool (KPROBES || PERF_EVENTS)
  64
  65 config OUTPUT_FORMAT
  66         string
  67         default "elf32-i386" if X86_32
  68         default "elf64-x86-64" if X86_64
  69
  70 config ARCH_DEFCONFIG
  71         string
  72         default "arch/x86/configs/i386_defconfig" if X86_32
  73         default "arch/x86/configs/x86_64_defconfig" if X86_64
  74
  75 config GENERIC_TIME
  76         def_bool y
  77
  78 config GENERIC_CMOS_UPDATE
  79         def_bool y
  80
  81 config CLOCKSOURCE_WATCHDOG
  82         def_bool y
  83
  84 config GENERIC_CLOCKEVENTS
  85         def_bool y
  86
  87 config GENERIC_CLOCKEVENTS_BROADCAST
  88         def_bool y
  89         depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  90
  91 config LOCKDEP_SUPPORT
  92         def_bool y
  93
  94 config STACKTRACE_SUPPORT
  95         def_bool y
  96
  97 config HAVE_LATENCYTOP_SUPPORT
  98         def_bool y
  99
 100 config MMU
 101         def_bool y
 102
 103 config ZONE_DMA
 104         def_bool y
 105
 106 config SBUS
 107         bool
 108
 109 config NEED_DMA_MAP_STATE
 110        def_bool (X86_64 || DMAR || DMA_API_DEBUG)
 111
 112 config GENERIC_ISA_DMA
 113         def_bool y
 114
 115 config GENERIC_IOMAP
 116         def_bool y
 117
 118 config GENERIC_BUG
 119         def_bool y
 120         depends on BUG
 121         select GENERIC_BUG_RELATIVE_POINTERS if X86_64
 122
 123 config GENERIC_BUG_RELATIVE_POINTERS
 124         bool
 125
 126 config GENERIC_HWEIGHT
 127         def_bool y
 128
 129 config GENERIC_GPIO
 130         bool
 131
 132 config ARCH_MAY_HAVE_PC_FDC
 133         def_bool y
 134
 135 config RWSEM_GENERIC_SPINLOCK
 136         def_bool !X86_XADD
 137
 138 config RWSEM_XCHGADD_ALGORITHM
 139         def_bool X86_XADD
 140
 141 config ARCH_HAS_CPU_IDLE_WAIT
 142         def_bool y
 143
 144 config GENERIC_CALIBRATE_DELAY
 145         def_bool y
 146
 147 config GENERIC_TIME_VSYSCALL
 148         bool
 149         default X86_64
 150
 151 config ARCH_HAS_CPU_RELAX
 152         def_bool y
 153
 154 config ARCH_HAS_DEFAULT_IDLE
 155         def_bool y
 156
 157 config ARCH_HAS_CACHE_LINE_SIZE
 158         def_bool y
 159
 160 config HAVE_SETUP_PER_CPU_AREA
 161         def_bool y
 162
 163 config NEED_PER_CPU_EMBED_FIRST_CHUNK
 164         def_bool y
 165
 166 config NEED_PER_CPU_PAGE_FIRST_CHUNK
 167         def_bool y
 168
 169 config HAVE_CPUMASK_OF_CPU_MAP
 170         def_bool X86_64_SMP
 171
 172 config ARCH_HIBERNATION_POSSIBLE
 173         def_bool y
 174
 175 config ARCH_SUSPEND_POSSIBLE
 176         def_bool y
 177
 178 config ZONE_DMA32
 179         bool
 180         default X86_64
 181
 182 config ARCH_POPULATES_NODE_MAP
 183         def_bool y
 184
 185 config AUDIT_ARCH
 186         bool
 187         default X86_64
 188
 189 config ARCH_SUPPORTS_OPTIMIZED_INLINING
 190         def_bool y
 191
 192 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
 193         def_bool y
 194
 195 config HAVE_EARLY_RES
 196         def_bool y
 197
 198 config HAVE_INTEL_TXT
 199         def_bool y
 200         depends on EXPERIMENTAL && DMAR && ACPI
 201
 202 # Use the generic interrupt handling code in kernel/irq/:
 203 config GENERIC_HARDIRQS
 204         def_bool y
 205
 206 config GENERIC_HARDIRQS_NO__DO_IRQ
 207        def_bool y
 208
 209 config GENERIC_IRQ_PROBE
 210         def_bool y
 211
 212 config GENERIC_PENDING_IRQ
 213         def_bool y
 214         depends on GENERIC_HARDIRQS && SMP
 215
 216 config USE_GENERIC_SMP_HELPERS
 217         def_bool y
 218         depends on SMP
 219
 220 config X86_32_SMP
 221         def_bool y
 222         depends on X86_32 && SMP
 223
 224 config X86_64_SMP
 225         def_bool y
 226         depends on X86_64 && SMP
 227
 228 config X86_HT
 229         def_bool y
 230         depends on SMP
 231
 232 config X86_TRAMPOLINE
 233         def_bool y
 234         depends on SMP || (64BIT && ACPI_SLEEP)
 235
 236 config X86_32_LAZY_GS
 237         def_bool y
 238         depends on X86_32 && !CC_STACKPROTECTOR
 239
 240 config ARCH_HWEIGHT_CFLAGS
 241         string
 242         default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
 243         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
 244
 245 config KTIME_SCALAR
 246         def_bool X86_32
 247 source "init/Kconfig"
 248 source "kernel/Kconfig.freezer"
 249
 250 menu "Processor type and features"
 251
 252 source "kernel/time/Kconfig"
 253
 254 config SMP
 255         bool "Symmetric multi-processing support"
 256         ---help---
 257           This enables support for systems with more than one CPU. If you have
 258           a system with only one CPU, like most personal computers, say N. If
 259           you have a system with more than one CPU, say Y.
 260
 261           If you say N here, the kernel will run on single and multiprocessor
 262           machines, but will use only one CPU of a multiprocessor machine. If
 263           you say Y here, the kernel will run on many, but not all,
 264           singleprocessor machines. On a singleprocessor machine, the kernel
 265           will run faster if you say N here.
 266
 267           Note that if you say Y here and choose architecture "586" or
 268           "Pentium" under "Processor family", the kernel will not work on 486
 269           architectures. Similarly, multiprocessor kernels for the "PPro"
 270           architecture may not work on all Pentium based boards.
 271
 272           People using multiprocessor machines who say Y here should also say
 273           Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
 274           Management" code will be disabled if you say Y here.
 275
 276           See also <file:Documentation/i386/IO-APIC.txt>,
 277           <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
 278           <http://www.tldp.org/docs.html#howto>.
 279
 280           If you don't know what to do here, say N.
 281
 282 config X86_X2APIC
 283         bool "Support x2apic"
 284         depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
 285         ---help---
 286           This enables x2apic support on CPUs that have this feature.
 287
 288           This allows 32-bit apic IDs (so it can support very large systems),
 289           and accesses the local apic via MSRs not via mmio.
 290
 291           If you don't know what to do here, say N.
 292
 293 config SPARSE_IRQ
 294         bool "Support sparse irq numbering"
 295         depends on PCI_MSI || HT_IRQ
 296         ---help---
 297           This enables support for sparse irqs. This is useful for distro
 298           kernels that want to define a high CONFIG_NR_CPUS value but still
 299           want to have low kernel memory footprint on smaller machines.
 300
 301           ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
 302             out the irq_desc[] array in a more NUMA-friendly way. )
 303
 304           If you don't know what to do here, say N.
 305
 306 config NUMA_IRQ_DESC
 307         def_bool y
 308         depends on SPARSE_IRQ && NUMA
 309
 310 config X86_MPPARSE
 311         bool "Enable MPS table" if ACPI
 312         default y
 313         depends on X86_LOCAL_APIC
 314         ---help---
 315           For old smp systems that do not have proper acpi support. Newer systems
 316           (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
 317
 318 config X86_BIGSMP
 319         bool "Support for big SMP systems with more than 8 CPUs"
 320         depends on X86_32 && SMP
 321         ---help---
 322           This option is needed for the systems that have more than 8 CPUs
 323
 324 if X86_32
 325 config X86_EXTENDED_PLATFORM
 326         bool "Support for extended (non-PC) x86 platforms"
 327         default y
 328         ---help---
 329           If you disable this option then the kernel will only support
 330           standard PC platforms. (which covers the vast majority of
 331           systems out there.)
 332
 333           If you enable this option then you'll be able to select support
 334           for the following (non-PC) 32 bit x86 platforms:
 335                 AMD Elan
 336                 NUMAQ (IBM/Sequent)
 337                 RDC R-321x SoC
 338                 SGI 320/540 (Visual Workstation)
 339                 Summit/EXA (IBM x440)
 340                 Unisys ES7000 IA32 series
 341                 Moorestown MID devices
 342
 343           If you have one of these systems, or if you want to build a
 344           generic distribution kernel, say Y here - otherwise say N.
 345 endif
 346
 347 if X86_64
 348 config X86_EXTENDED_PLATFORM
 349         bool "Support for extended (non-PC) x86 platforms"
 350         default y
 351         ---help---
 352           If you disable this option then the kernel will only support
 353           standard PC platforms. (which covers the vast majority of
 354           systems out there.)
 355
 356           If you enable this option then you'll be able to select support
 357           for the following (non-PC) 64 bit x86 platforms:
 358                 ScaleMP vSMP
 359                 SGI Ultraviolet
 360
 361           If you have one of these systems, or if you want to build a
 362           generic distribution kernel, say Y here - otherwise say N.
 363 endif
 364 # This is an alphabetically sorted list of 64 bit extended platforms
 365 # Please maintain the alphabetic order if and when there are additions
 366
 367 config X86_VSMP
 368         bool "ScaleMP vSMP"
 369         select PARAVIRT
 370         depends on X86_64 && PCI
 371         depends on X86_EXTENDED_PLATFORM
 372         ---help---
 373           Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
 374           supposed to run on these EM64T-based machines.  Only choose this option
 375           if you have one of these machines.
 376
 377 config X86_UV
 378         bool "SGI Ultraviolet"
 379         depends on X86_64
 380         depends on X86_EXTENDED_PLATFORM
 381         depends on NUMA
 382         depends on X86_X2APIC
 383         ---help---
 384           This option is needed in order to support SGI Ultraviolet systems.
 385           If you don't have one of these, you should say N here.
 386
 387 # Following is an alphabetically sorted list of 32 bit extended platforms
 388 # Please maintain the alphabetic order if and when there are additions
 389
 390 config X86_ELAN
 391         bool "AMD Elan"
 392         depends on X86_32
 393         depends on X86_EXTENDED_PLATFORM
 394         ---help---
 395           Select this for an AMD Elan processor.
 396
 397           Do not use this option for K6/Athlon/Opteron processors!
 398
 399           If unsure, choose "PC-compatible" instead.
 400
 401 config X86_MRST
 402        bool "Moorestown MID platform"
 403         depends on PCI
 404         depends on PCI_GOANY
 405         depends on X86_32
 406         depends on X86_EXTENDED_PLATFORM
 407         depends on X86_IO_APIC
 408         select APB_TIMER
 409         ---help---
 410           Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
 411           Internet Device(MID) platform. Moorestown consists of two chips:
 412           Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
 413           Unlike standard x86 PCs, Moorestown does not have many legacy devices
 414           nor standard legacy replacement devices/features. e.g. Moorestown does
 415           not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
 416
 417 config X86_RDC321X
 418         bool "RDC R-321x SoC"
 419         depends on X86_32
 420         depends on X86_EXTENDED_PLATFORM
 421         select M486
 422         select X86_REBOOTFIXUPS
 423         ---help---
 424           This option is needed for RDC R-321x system-on-chip, also known
 425           as R-8610-(G).
 426           If you don't have one of these chips, you should say N here.
 427
 428 config X86_32_NON_STANDARD
 429         bool "Support non-standard 32-bit SMP architectures"
 430         depends on X86_32 && SMP
 431         depends on X86_EXTENDED_PLATFORM
 432         ---help---
 433           This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
 434           subarchitectures.  It is intended for a generic binary kernel.
 435           if you select them all, kernel will probe it one by one. and will
 436           fallback to default.
 437
 438 # Alphabetically sorted list of Non standard 32 bit platforms
 439
 440 config X86_NUMAQ
 441         bool "NUMAQ (IBM/Sequent)"
 442         depends on X86_32_NON_STANDARD
 443         depends on PCI
 444         select NUMA
 445         select X86_MPPARSE
 446         ---help---
 447           This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
 448           NUMA multiquad box. This changes the way that processors are
 449           bootstrapped, and uses Clustered Logical APIC addressing mode instead
 450           of Flat Logical.  You will need a new lynxer.elf file to flash your
 451           firmware with - send email to <Martin.Bligh@us.ibm.com>.
 452
 453 config X86_SUPPORTS_MEMORY_FAILURE
 454         def_bool y
 455         # MCE code calls memory_failure():
 456         depends on X86_MCE
 457         # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
 458         depends on !X86_NUMAQ
 459         # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
 460         depends on X86_64 || !SPARSEMEM
 461         select ARCH_SUPPORTS_MEMORY_FAILURE
 462
 463 config X86_VISWS
 464         bool "SGI 320/540 (Visual Workstation)"
 465         depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
 466         depends on X86_32_NON_STANDARD
 467         ---help---
 468           The SGI Visual Workstation series is an IA32-based workstation
 469           based on SGI systems chips with some legacy PC hardware attached.
 470
 471           Say Y here to create a kernel to run on the SGI 320 or 540.
 472
 473           A kernel compiled for the Visual Workstation will run on general
 474           PCs as well. See <file:Documentation/sgi-visws.txt> for details.
 475
 476 config X86_SUMMIT
 477         bool "Summit/EXA (IBM x440)"
 478         depends on X86_32_NON_STANDARD
 479         ---help---
 480           This option is needed for IBM systems that use the Summit/EXA chipset.
 481           In particular, it is needed for the x440.
 482
 483 config X86_ES7000
 484         bool "Unisys ES7000 IA32 series"
 485         depends on X86_32_NON_STANDARD && X86_BIGSMP
 486         ---help---
 487           Support for Unisys ES7000 systems.  Say 'Y' here if this kernel is
 488           supposed to run on an IA32-based Unisys ES7000 system.
 489
 490 config SCHED_OMIT_FRAME_POINTER
 491         def_bool y
 492         prompt "Single-depth WCHAN output"
 493         depends on X86
 494         ---help---
 495           Calculate simpler /proc/<PID>/wchan values. If this option
 496           is disabled then wchan values will recurse back to the
 497           caller function. This provides more accurate wchan values,
 498           at the expense of slightly more scheduling overhead.
 499
 500           If in doubt, say "Y".
 501
 502 menuconfig PARAVIRT_GUEST
 503         bool "Paravirtualized guest support"
 504         ---help---
 505           Say Y here to get to see options related to running Linux under
 506           various hypervisors.  This option alone does not add any kernel code.
 507
 508           If you say N, all options in this submenu will be skipped and disabled.
 509
 510 if PARAVIRT_GUEST
 511
 512 source "arch/x86/xen/Kconfig"
 513
 514 config VMI
 515         bool "VMI Guest support (DEPRECATED)"
 516         select PARAVIRT
 517         depends on X86_32
 518         ---help---
 519           VMI provides a paravirtualized interface to the VMware ESX server
 520           (it could be used by other hypervisors in theory too, but is not
 521           at the moment), by linking the kernel to a GPL-ed ROM module
 522           provided by the hypervisor.
 523
 524           As of September 2009, VMware has started a phased retirement
 525           of this feature from VMware's products. Please see
 526           feature-removal-schedule.txt for details.  If you are
 527           planning to enable this option, please note that you cannot
 528           live migrate a VMI enabled VM to a future VMware product,
 529           which doesn't support VMI. So if you expect your kernel to
 530           seamlessly migrate to newer VMware products, keep this
 531           disabled.
 532
 533 config KVM_CLOCK
 534         bool "KVM paravirtualized clock"
 535         select PARAVIRT
 536         select PARAVIRT_CLOCK
 537         ---help---
 538           Turning on this option will allow you to run a paravirtualized clock
 539           when running over the KVM hypervisor. Instead of relying on a PIT
 540           (or probably other) emulation by the underlying device model, the host
 541           provides the guest with timing infrastructure such as time of day, and
 542           system time
 543
 544 config KVM_GUEST
 545         bool "KVM Guest support"
 546         select PARAVIRT
 547         ---help---
 548           This option enables various optimizations for running under the KVM
 549           hypervisor.
 550
 551 source "arch/x86/lguest/Kconfig"
 552
 553 config PARAVIRT
 554         bool "Enable paravirtualization code"
 555         ---help---
 556           This changes the kernel so it can modify itself when it is run
 557           under a hypervisor, potentially improving performance significantly
 558           over full virtualization.  However, when run without a hypervisor
 559           the kernel is theoretically slower and slightly larger.
 560
 561 config PARAVIRT_SPINLOCKS
 562         bool "Paravirtualization layer for spinlocks"
 563         depends on PARAVIRT && SMP && EXPERIMENTAL
 564         ---help---
 565           Paravirtualized spinlocks allow a pvops backend to replace the
 566           spinlock implementation with something virtualization-friendly
 567           (for example, block the virtual CPU rather than spinning).
 568
 569           Unfortunately the downside is an up to 5% performance hit on
 570           native kernels, with various workloads.
 571
 572           If you are unsure how to answer this question, answer N.
 573
 574 config PARAVIRT_CLOCK
 575         bool
 576
 577 endif
 578
 579 config PARAVIRT_DEBUG
 580         bool "paravirt-ops debugging"
 581         depends on PARAVIRT && DEBUG_KERNEL
 582         ---help---
 583           Enable to debug paravirt_ops internals.  Specifically, BUG if
 584           a paravirt_op is missing when it is called.
 585
 586 config NO_BOOTMEM
 587         default y
 588         bool "Disable Bootmem code"
 589         ---help---
 590           Use early_res directly instead of bootmem before slab is ready.
 591                 - allocator (buddy) [generic]
 592                 - early allocator (bootmem) [generic]
 593                 - very early allocator (reserve_early*()) [x86]
 594                 - very very early allocator (early brk model) [x86]
 595           So reduce one layer between early allocator to final allocator
 596
 597
 598 config MEMTEST
 599         bool "Memtest"
 600         ---help---
 601           This option adds a kernel parameter 'memtest', which allows memtest
 602           to be set.
 603                 memtest=0, mean disabled; -- default
 604                 memtest=1, mean do 1 test pattern;
 605                 ...
 606                 memtest=4, mean do 4 test patterns.
 607           If you are unsure how to answer this question, answer N.
 608
 609 config X86_SUMMIT_NUMA
 610         def_bool y
 611         depends on X86_32 && NUMA && X86_32_NON_STANDARD
 612
 613 config X86_CYCLONE_TIMER
 614         def_bool y
 615         depends on X86_32_NON_STANDARD
 616
 617 source "arch/x86/Kconfig.cpu"
 618
 619 config HPET_TIMER
 620         def_bool X86_64
 621         prompt "HPET Timer Support" if X86_32
 622         ---help---
 623           Use the IA-PC HPET (High Precision Event Timer) to manage
 624           time in preference to the PIT and RTC, if a HPET is
 625           present.
 626           HPET is the next generation timer replacing legacy 8254s.
 627           The HPET provides a stable time base on SMP
 628           systems, unlike the TSC, but it is more expensive to access,
 629           as it is off-chip.  You can find the HPET spec at
 630           <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
 631
 632           You can safely choose Y here.  However, HPET will only be
 633           activated if the platform and the BIOS support this feature.
 634           Otherwise the 8254 will be used for timing services.
 635
 636           Choose N to continue using the legacy 8254 timer.
 637
 638 config HPET_EMULATE_RTC
 639         def_bool y
 640         depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
 641
 642 config APB_TIMER
 643        def_bool y if MRST
 644        prompt "Langwell APB Timer Support" if X86_MRST
 645        help
 646          APB timer is the replacement for 8254, HPET on X86 MID platforms.
 647          The APBT provides a stable time base on SMP
 648          systems, unlike the TSC, but it is more expensive to access,
 649          as it is off-chip. APB timers are always running regardless of CPU
 650          C states, they are used as per CPU clockevent device when possible.
 651
 652 # Mark as embedded because too many people got it wrong.
 653 # The code disables itself when not needed.
 654 config DMI
 655         default y
 656         bool "Enable DMI scanning" if EMBEDDED
 657         ---help---
 658           Enabled scanning of DMI to identify machine quirks. Say Y
 659           here unless you have verified that your setup is not
 660           affected by entries in the DMI blacklist. Required by PNP
 661           BIOS code.
 662
 663 config GART_IOMMU
 664         bool "GART IOMMU support" if EMBEDDED
 665         default y
 666         select SWIOTLB
 667         depends on X86_64 && PCI && K8_NB
 668         ---help---
 669           Support for full DMA access of devices with 32bit memory access only
 670           on systems with more than 3GB. This is usually needed for USB,
 671           sound, many IDE/SATA chipsets and some other devices.
 672           Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
 673           based hardware IOMMU and a software bounce buffer based IOMMU used
 674           on Intel systems and as fallback.
 675           The code is only active when needed (enough memory and limited
 676           device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
 677           too.
 678
 679 config CALGARY_IOMMU
 680         bool "IBM Calgary IOMMU support"
 681         select SWIOTLB
 682         depends on X86_64 && PCI && EXPERIMENTAL
 683         ---help---
 684           Support for hardware IOMMUs in IBM's xSeries x366 and x460
 685           systems. Needed to run systems with more than 3GB of memory
 686           properly with 32-bit PCI devices that do not support DAC
 687           (Double Address Cycle). Calgary also supports bus level
 688           isolation, where all DMAs pass through the IOMMU.  This
 689           prevents them from going anywhere except their intended
 690           destination. This catches hard-to-find kernel bugs and
 691           mis-behaving drivers and devices that do not use the DMA-API
 692           properly to set up their DMA buffers.  The IOMMU can be
 693           turned off at boot time with the iommu=off parameter.
 694           Normally the kernel will make the right choice by itself.
 695           If unsure, say Y.
 696
 697 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
 698         def_bool y
 699         prompt "Should Calgary be enabled by default?"
 700         depends on CALGARY_IOMMU
 701         ---help---
 702           Should Calgary be enabled by default? if you choose 'y', Calgary
 703           will be used (if it exists). If you choose 'n', Calgary will not be
 704           used even if it exists. If you choose 'n' and would like to use
 705           Calgary anyway, pass 'iommu=calgary' on the kernel command line.
 706           If unsure, say Y.
 707
 708 config AMD_IOMMU
 709         bool "AMD IOMMU support"
 710         select SWIOTLB
 711         select PCI_MSI
 712         depends on X86_64 && PCI && ACPI
 713         ---help---
 714           With this option you can enable support for AMD IOMMU hardware in
 715           your system. An IOMMU is a hardware component which provides
 716           remapping of DMA memory accesses from devices. With an AMD IOMMU you
 717           can isolate the the DMA memory of different devices and protect the
 718           system from misbehaving device drivers or hardware.
 719
 720           You can find out if your system has an AMD IOMMU if you look into
 721           your BIOS for an option to enable it or if you have an IVRS ACPI
 722           table.
 723
 724 config AMD_IOMMU_STATS
 725         bool "Export AMD IOMMU statistics to debugfs"
 726         depends on AMD_IOMMU
 727         select DEBUG_FS
 728         ---help---
 729           This option enables code in the AMD IOMMU driver to collect various
 730           statistics about whats happening in the driver and exports that
 731           information to userspace via debugfs.
 732           If unsure, say N.
 733
 734 # need this always selected by IOMMU for the VIA workaround
 735 config SWIOTLB
 736         def_bool y if X86_64
 737         ---help---
 738           Support for software bounce buffers used on x86-64 systems
 739           which don't have a hardware IOMMU (e.g. the current generation
 740           of Intel's x86-64 CPUs). Using this PCI devices which can only
 741           access 32-bits of memory can be used on systems with more than
 742           3 GB of memory. If unsure, say Y.
 743
 744 config IOMMU_HELPER
 745         def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
 746
 747 config IOMMU_API
 748         def_bool (AMD_IOMMU || DMAR)
 749
 750 config MAXSMP
 751         bool "Configure Maximum number of SMP Processors and NUMA Nodes"
 752         depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
 753         select CPUMASK_OFFSTACK
 754         ---help---
 755           Configure maximum number of CPUS and NUMA Nodes for this architecture.
 756           If unsure, say N.
 757
 758 config NR_CPUS
 759         int "Maximum number of CPUs" if SMP && !MAXSMP
 760         range 2 8 if SMP && X86_32 && !X86_BIGSMP
 761         range 2 512 if SMP && !MAXSMP
 762         default "1" if !SMP
 763         default "4096" if MAXSMP
 764         default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
 765         default "8" if SMP
 766         ---help---
 767           This allows you to specify the maximum number of CPUs which this
 768           kernel will support.  The maximum supported value is 512 and the
 769           minimum value which makes sense is 2.
 770
 771           This is purely to save memory - each supported CPU adds
 772           approximately eight kilobytes to the kernel image.
 773
 774 config SCHED_SMT
 775         bool "SMT (Hyperthreading) scheduler support"
 776         depends on X86_HT
 777         ---help---
 778           SMT scheduler support improves the CPU scheduler's decision making
 779           when dealing with Intel Pentium 4 chips with HyperThreading at a
 780           cost of slightly increased overhead in some places. If unsure say
 781           N here.
 782
 783 config SCHED_MC
 784         def_bool y
 785         prompt "Multi-core scheduler support"
 786         depends on X86_HT
 787         ---help---
 788           Multi-core scheduler support improves the CPU scheduler's decision
 789           making when dealing with multi-core CPU chips at a cost of slightly
 790           increased overhead in some places. If unsure say N here.
 791
 792 source "kernel/Kconfig.preempt"
 793
 794 config X86_UP_APIC
 795         bool "Local APIC support on uniprocessors"
 796         depends on X86_32 && !SMP && !X86_32_NON_STANDARD
 797         ---help---
 798           A local APIC (Advanced Programmable Interrupt Controller) is an
 799           integrated interrupt controller in the CPU. If you have a single-CPU
 800           system which has a processor with a local APIC, you can say Y here to
 801           enable and use it. If you say Y here even though your machine doesn't
 802           have a local APIC, then the kernel will still run with no slowdown at
 803           all. The local APIC supports CPU-generated self-interrupts (timer,
 804           performance counters), and the NMI watchdog which detects hard
 805           lockups.
 806
 807 config X86_UP_IOAPIC
 808         bool "IO-APIC support on uniprocessors"
 809         depends on X86_UP_APIC
 810         ---help---
 811           An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
 812           SMP-capable replacement for PC-style interrupt controllers. Most
 813           SMP systems and many recent uniprocessor systems have one.
 814
 815           If you have a single-CPU system with an IO-APIC, you can say Y here
 816           to use it. If you say Y here even though your machine doesn't have
 817           an IO-APIC, then the kernel will still run with no slowdown at all.
 818
 819 config X86_LOCAL_APIC
 820         def_bool y
 821         depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
 822
 823 config X86_IO_APIC
 824         def_bool y
 825         depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
 826
 827 config X86_VISWS_APIC
 828         def_bool y
 829         depends on X86_32 && X86_VISWS
 830
 831 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
 832         bool "Reroute for broken boot IRQs"
 833         depends on X86_IO_APIC
 834         ---help---
 835           This option enables a workaround that fixes a source of
 836           spurious interrupts. This is recommended when threaded
 837           interrupt handling is used on systems where the generation of
 838           superfluous "boot interrupts" cannot be disabled.
 839
 840           Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
 841           entry in the chipset's IO-APIC is masked (as, e.g. the RT
 842           kernel does during interrupt handling). On chipsets where this
 843           boot IRQ generation cannot be disabled, this workaround keeps
 844           the original IRQ line masked so that only the equivalent "boot
 845           IRQ" is delivered to the CPUs. The workaround also tells the
 846           kernel to set up the IRQ handler on the boot IRQ line. In this
 847           way only one interrupt is delivered to the kernel. Otherwise
 848           the spurious second interrupt may cause the kernel to bring
 849           down (vital) interrupt lines.
 850
 851           Only affects "broken" chipsets. Interrupt sharing may be
 852           increased on these systems.
 853
 854 config X86_MCE
 855         bool "Machine Check / overheating reporting"
 856         ---help---
 857           Machine Check support allows the processor to notify the
 858           kernel if it detects a problem (e.g. overheating, data corruption).
 859           The action the kernel takes depends on the severity of the problem,
 860           ranging from warning messages to halting the machine.
 861
 862 config X86_MCE_INTEL
 863         def_bool y
 864         prompt "Intel MCE features"
 865         depends on X86_MCE && X86_LOCAL_APIC
 866         ---help---
 867            Additional support for intel specific MCE features such as
 868            the thermal monitor.
 869
 870 config X86_MCE_AMD
 871         def_bool y
 872         prompt "AMD MCE features"
 873         depends on X86_MCE && X86_LOCAL_APIC
 874         ---help---
 875            Additional support for AMD specific MCE features such as
 876            the DRAM Error Threshold.
 877
 878 config X86_ANCIENT_MCE
 879         bool "Support for old Pentium 5 / WinChip machine checks"
 880         depends on X86_32 && X86_MCE
 881         ---help---
 882           Include support for machine check handling on old Pentium 5 or WinChip
 883           systems. These typically need to be enabled explicitely on the command
 884           line.
 885
 886 config X86_MCE_THRESHOLD
 887         depends on X86_MCE_AMD || X86_MCE_INTEL
 888         def_bool y
 889
 890 config X86_MCE_INJECT
 891         depends on X86_MCE
 892         tristate "Machine check injector support"
 893         ---help---
 894           Provide support for injecting machine checks for testing purposes.
 895           If you don't know what a machine check is and you don't do kernel
 896           QA it is safe to say n.
 897
 898 config X86_THERMAL_VECTOR
 899         def_bool y
 900         depends on X86_MCE_INTEL
 901
 902 config VM86
 903         bool "Enable VM86 support" if EMBEDDED
 904         default y
 905         depends on X86_32
 906         ---help---
 907           This option is required by programs like DOSEMU to run 16-bit legacy
 908           code on X86 processors. It also may be needed by software like
 909           XFree86 to initialize some video cards via BIOS. Disabling this
 910           option saves about 6k.
 911
 912 config TOSHIBA
 913         tristate "Toshiba Laptop support"
 914         depends on X86_32
 915         ---help---
 916           This adds a driver to safely access the System Management Mode of
 917           the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
 918           not work on models with a Phoenix BIOS. The System Management Mode
 919           is used to set the BIOS and power saving options on Toshiba portables.
 920
 921           For information on utilities to make use of this driver see the
 922           Toshiba Linux utilities web site at:
 923           <http://www.buzzard.org.uk/toshiba/>.
 924
 925           Say Y if you intend to run this kernel on a Toshiba portable.
 926           Say N otherwise.
 927
 928 config I8K
 929         tristate "Dell laptop support"
 930         ---help---
 931           This adds a driver to safely access the System Management Mode
 932           of the CPU on the Dell Inspiron 8000. The System Management Mode
 933           is used to read cpu temperature and cooling fan status and to
 934           control the fans on the I8K portables.
 935
 936           This driver has been tested only on the Inspiron 8000 but it may
 937           also work with other Dell laptops. You can force loading on other
 938           models by passing the parameter `force=1' to the module. Use at
 939           your own risk.
 940
 941           For information on utilities to make use of this driver see the
 942           I8K Linux utilities web site at:
 943           <http://people.debian.org/~dz/i8k/>
 944
 945           Say Y if you intend to run this kernel on a Dell Inspiron 8000.
 946           Say N otherwise.
 947
 948 config X86_REBOOTFIXUPS
 949         bool "Enable X86 board specific fixups for reboot"
 950         depends on X86_32
 951         ---help---
 952           This enables chipset and/or board specific fixups to be done
 953           in order to get reboot to work correctly. This is only needed on
 954           some combinations of hardware and BIOS. The symptom, for which
 955           this config is intended, is when reboot ends with a stalled/hung
 956           system.
 957
 958           Currently, the only fixup is for the Geode machines using
 959           CS5530A and CS5536 chipsets and the RDC R-321x SoC.
 960
 961           Say Y if you want to enable the fixup. Currently, it's safe to
 962           enable this option even if you don't need it.
 963           Say N otherwise.
 964
 965 config MICROCODE
 966         tristate "/dev/cpu/microcode - microcode support"
 967         select FW_LOADER
 968         ---help---
 969           If you say Y here, you will be able to update the microcode on
 970           certain Intel and AMD processors. The Intel support is for the
 971           IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
 972           Pentium 4, Xeon etc. The AMD support is for family 0x10 and
 973           0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
 974           You will obviously need the actual microcode binary data itself
 975           which is not shipped with the Linux kernel.
 976
 977           This option selects the general module only, you need to select
 978           at least one vendor specific module as well.
 979
 980           To compile this driver as a module, choose M here: the
 981           module will be called microcode.
 982
 983 config MICROCODE_INTEL
 984         bool "Intel microcode patch loading support"
 985         depends on MICROCODE
 986         default MICROCODE
 987         select FW_LOADER
 988         ---help---
 989           This options enables microcode patch loading support for Intel
 990           processors.
 991
 992           For latest news and information on obtaining all the required
 993           Intel ingredients for this driver, check:
 994           <http://www.urbanmyth.org/microcode/>.
 995
 996 config MICROCODE_AMD
 997         bool "AMD microcode patch loading support"
 998         depends on MICROCODE
 999         select FW_LOADER
1000         ---help---
1001           If you select this option, microcode patch loading support for AMD
1002           processors will be enabled.
1003
1004 config MICROCODE_OLD_INTERFACE
1005         def_bool y
1006         depends on MICROCODE
1007
1008 config X86_MSR
1009         tristate "/dev/cpu/*/msr - Model-specific register support"
1010         ---help---
1011           This device gives privileged processes access to the x86
1012           Model-Specific Registers (MSRs).  It is a character device with
1013           major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1014           MSR accesses are directed to a specific CPU on multi-processor
1015           systems.
1016
1017 config X86_CPUID
1018         tristate "/dev/cpu/*/cpuid - CPU information support"
1019         ---help---
1020           This device gives processes access to the x86 CPUID instruction to
1021           be executed on a specific processor.  It is a character device
1022           with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1023           /dev/cpu/31/cpuid.
1024
1025 choice
1026         prompt "High Memory Support"
1027         default HIGHMEM64G if X86_NUMAQ
1028         default HIGHMEM4G
1029         depends on X86_32
1030
1031 config NOHIGHMEM
1032         bool "off"
1033         depends on !X86_NUMAQ
1034         ---help---
1035           Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1036           However, the address space of 32-bit x86 processors is only 4
1037           Gigabytes large. That means that, if you have a large amount of
1038           physical memory, not all of it can be "permanently mapped" by the
1039           kernel. The physical memory that's not permanently mapped is called
1040           "high memory".
1041
1042           If you are compiling a kernel which will never run on a machine with
1043           more than 1 Gigabyte total physical RAM, answer "off" here (default
1044           choice and suitable for most users). This will result in a "3GB/1GB"
1045           split: 3GB are mapped so that each process sees a 3GB virtual memory
1046           space and the remaining part of the 4GB virtual memory space is used
1047           by the kernel to permanently map as much physical memory as
1048           possible.
1049
1050           If the machine has between 1 and 4 Gigabytes physical RAM, then
1051           answer "4GB" here.
1052
1053           If more than 4 Gigabytes is used then answer "64GB" here. This
1054           selection turns Intel PAE (Physical Address Extension) mode on.
1055           PAE implements 3-level paging on IA32 processors. PAE is fully
1056           supported by Linux, PAE mode is implemented on all recent Intel
1057           processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1058           then the kernel will not boot on CPUs that don't support PAE!
1059
1060           The actual amount of total physical memory will either be
1061           auto detected or can be forced by using a kernel command line option
1062           such as "mem=256M". (Try "man bootparam" or see the documentation of
1063           your boot loader (lilo or loadlin) about how to pass options to the
1064           kernel at boot time.)
1065
1066           If unsure, say "off".
1067
1068 config HIGHMEM4G
1069         bool "4GB"
1070         depends on !X86_NUMAQ
1071         ---help---
1072           Select this if you have a 32-bit processor and between 1 and 4
1073           gigabytes of physical RAM.
1074
1075 config HIGHMEM64G
1076         bool "64GB"
1077         depends on !M386 && !M486
1078         select X86_PAE
1079         ---help---
1080           Select this if you have a 32-bit processor and more than 4
1081           gigabytes of physical RAM.
1082
1083 endchoice
1084
1085 choice
1086         depends on EXPERIMENTAL
1087         prompt "Memory split" if EMBEDDED
1088         default VMSPLIT_3G
1089         depends on X86_32
1090         ---help---
1091           Select the desired split between kernel and user memory.
1092
1093           If the address range available to the kernel is less than the
1094           physical memory installed, the remaining memory will be available
1095           as "high memory". Accessing high memory is a little more costly
1096           than low memory, as it needs to be mapped into the kernel first.
1097           Note that increasing the kernel address space limits the range
1098           available to user programs, making the address space there
1099           tighter.  Selecting anything other than the default 3G/1G split
1100           will also likely make your kernel incompatible with binary-only
1101           kernel modules.
1102
1103           If you are not absolutely sure what you are doing, leave this
1104           option alone!
1105
1106         config VMSPLIT_3G
1107                 bool "3G/1G user/kernel split"
1108         config VMSPLIT_3G_OPT
1109                 depends on !X86_PAE
1110                 bool "3G/1G user/kernel split (for full 1G low memory)"
1111         config VMSPLIT_2G
1112                 bool "2G/2G user/kernel split"
1113         config VMSPLIT_2G_OPT
1114                 depends on !X86_PAE
1115                 bool "2G/2G user/kernel split (for full 2G low memory)"
1116         config VMSPLIT_1G
1117                 bool "1G/3G user/kernel split"
1118 endchoice
1119
1120 config PAGE_OFFSET
1121         hex
1122         default 0xB0000000 if VMSPLIT_3G_OPT
1123         default 0x80000000 if VMSPLIT_2G
1124         default 0x78000000 if VMSPLIT_2G_OPT
1125         default 0x40000000 if VMSPLIT_1G
1126         default 0xC0000000
1127         depends on X86_32
1128
1129 config HIGHMEM
1130         def_bool y
1131         depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1132
1133 config X86_PAE
1134         bool "PAE (Physical Address Extension) Support"
1135         depends on X86_32 && !HIGHMEM4G
1136         ---help---
1137           PAE is required for NX support, and furthermore enables
1138           larger swapspace support for non-overcommit purposes. It
1139           has the cost of more pagetable lookup overhead, and also
1140           consumes more pagetable space per process.
1141
1142 config ARCH_PHYS_ADDR_T_64BIT
1143         def_bool X86_64 || X86_PAE
1144
1145 config DIRECT_GBPAGES
1146         bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
1147         default y
1148         depends on X86_64
1149         ---help---
1150           Allow the kernel linear mapping to use 1GB pages on CPUs that
1151           support it. This can improve the kernel's performance a tiny bit by
1152           reducing TLB pressure. If in doubt, say "Y".
1153
1154 # Common NUMA Features
1155 config NUMA
1156         bool "Numa Memory Allocation and Scheduler Support"
1157         depends on SMP
1158         depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1159         default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1160         ---help---
1161           Enable NUMA (Non Uniform Memory Access) support.
1162
1163           The kernel will try to allocate memory used by a CPU on the
1164           local memory controller of the CPU and add some more
1165           NUMA awareness to the kernel.
1166
1167           For 64-bit this is recommended if the system is Intel Core i7
1168           (or later), AMD Opteron, or EM64T NUMA.
1169
1170           For 32-bit this is only needed on (rare) 32-bit-only platforms
1171           that support NUMA topologies, such as NUMAQ / Summit, or if you
1172           boot a 32-bit kernel on a 64-bit NUMA platform.
1173
1174           Otherwise, you should say N.
1175
1176 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1177         depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1178
1179 config K8_NUMA
1180         def_bool y
1181         prompt "Old style AMD Opteron NUMA detection"
1182         depends on X86_64 && NUMA && PCI
1183         ---help---
1184           Enable K8 NUMA node topology detection.  You should say Y here if
1185           you have a multi processor AMD K8 system. This uses an old
1186           method to read the NUMA configuration directly from the builtin
1187           Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
1188           instead, which also takes priority if both are compiled in.
1189
1190 config X86_64_ACPI_NUMA
1191         def_bool y
1192         prompt "ACPI NUMA detection"
1193         depends on X86_64 && NUMA && ACPI && PCI
1194         select ACPI_NUMA
1195         ---help---
1196           Enable ACPI SRAT based node topology detection.
1197
1198 # Some NUMA nodes have memory ranges that span
1199 # other nodes.  Even though a pfn is valid and
1200 # between a node's start and end pfns, it may not
1201 # reside on that node.  See memmap_init_zone()
1202 # for details.
1203 config NODES_SPAN_OTHER_NODES
1204         def_bool y
1205         depends on X86_64_ACPI_NUMA
1206
1207 config NUMA_EMU
1208         bool "NUMA emulation"
1209         depends on X86_64 && NUMA
1210         ---help---
1211           Enable NUMA emulation. A flat machine will be split
1212           into virtual nodes when booted with "numa=fake=N", where N is the
1213           number of nodes. This is only useful for debugging.
1214
1215 config NODES_SHIFT
1216         int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1217         range 1 10
1218         default "10" if MAXSMP
1219         default "6" if X86_64
1220         default "4" if X86_NUMAQ
1221         default "3"
1222         depends on NEED_MULTIPLE_NODES
1223         ---help---
1224           Specify the maximum number of NUMA Nodes available on the target
1225           system.  Increases memory reserved to accommodate various tables.
1226
1227 config HAVE_ARCH_BOOTMEM
1228         def_bool y
1229         depends on X86_32 && NUMA
1230
1231 config ARCH_HAVE_MEMORY_PRESENT
1232         def_bool y
1233         depends on X86_32 && DISCONTIGMEM
1234
1235 config NEED_NODE_MEMMAP_SIZE
1236         def_bool y
1237         depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1238
1239 config HAVE_ARCH_ALLOC_REMAP
1240         def_bool y
1241         depends on X86_32 && NUMA
1242
1243 config ARCH_FLATMEM_ENABLE
1244         def_bool y
1245         depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
1246
1247 config ARCH_DISCONTIGMEM_ENABLE
1248         def_bool y
1249         depends on NUMA && X86_32
1250
1251 config ARCH_DISCONTIGMEM_DEFAULT
1252         def_bool y
1253         depends on NUMA && X86_32
1254
1255 config ARCH_PROC_KCORE_TEXT
1256         def_bool y
1257         depends on X86_64 && PROC_KCORE
1258
1259 config ARCH_SPARSEMEM_DEFAULT
1260         def_bool y
1261         depends on X86_64
1262
1263 config ARCH_SPARSEMEM_ENABLE
1264         def_bool y
1265         depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1266         select SPARSEMEM_STATIC if X86_32
1267         select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1268
1269 config ARCH_SELECT_MEMORY_MODEL
1270         def_bool y
1271         depends on ARCH_SPARSEMEM_ENABLE
1272
1273 config ARCH_MEMORY_PROBE
1274         def_bool X86_64
1275         depends on MEMORY_HOTPLUG
1276
1277 config ILLEGAL_POINTER_VALUE
1278        hex
1279        default 0 if X86_32
1280        default 0xdead000000000000 if X86_64
1281
1282 source "mm/Kconfig"
1283
1284 config HIGHPTE
1285         bool "Allocate 3rd-level pagetables from highmem"
1286         depends on HIGHMEM
1287         ---help---
1288           The VM uses one page table entry for each page of physical memory.
1289           For systems with a lot of RAM, this can be wasteful of precious
1290           low memory.  Setting this option will put user-space page table
1291           entries in high memory.
1292
1293 config X86_CHECK_BIOS_CORRUPTION
1294         bool "Check for low memory corruption"
1295         ---help---
1296           Periodically check for memory corruption in low memory, which
1297           is suspected to be caused by BIOS.  Even when enabled in the
1298           configuration, it is disabled at runtime.  Enable it by
1299           setting "memory_corruption_check=1" on the kernel command
1300           line.  By default it scans the low 64k of memory every 60
1301           seconds; see the memory_corruption_check_size and
1302           memory_corruption_check_period parameters in
1303           Documentation/kernel-parameters.txt to adjust this.
1304
1305           When enabled with the default parameters, this option has
1306           almost no overhead, as it reserves a relatively small amount
1307           of memory and scans it infrequently.  It both detects corruption
1308           and prevents it from affecting the running system.
1309
1310           It is, however, intended as a diagnostic tool; if repeatable
1311           BIOS-originated corruption always affects the same memory,
1312           you can use memmap= to prevent the kernel from using that
1313           memory.
1314
1315 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1316         bool "Set the default setting of memory_corruption_check"
1317         depends on X86_CHECK_BIOS_CORRUPTION
1318         default y
1319         ---help---
1320           Set whether the default state of memory_corruption_check is
1321           on or off.
1322
1323 config X86_RESERVE_LOW_64K
1324         bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
1325         default y
1326         ---help---
1327           Reserve the first 64K of physical RAM on BIOSes that are known
1328           to potentially corrupt that memory range. A numbers of BIOSes are
1329           known to utilize this area during suspend/resume, so it must not
1330           be used by the kernel.
1331
1332           Set this to N if you are absolutely sure that you trust the BIOS
1333           to get all its memory reservations and usages right.
1334
1335           If you have doubts about the BIOS (e.g. suspend/resume does not
1336           work or there's kernel crashes after certain hardware hotplug
1337           events) and it's not AMI or Phoenix, then you might want to enable
1338           X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
1339           corruption patterns.
1340
1341           Say Y if unsure.
1342
1343 config MATH_EMULATION
1344         bool
1345         prompt "Math emulation" if X86_32
1346         ---help---
1347           Linux can emulate a math coprocessor (used for floating point
1348           operations) if you don't have one. 486DX and Pentium processors have
1349           a math coprocessor built in, 486SX and 386 do not, unless you added
1350           a 487DX or 387, respectively. (The messages during boot time can
1351           give you some hints here ["man dmesg"].) Everyone needs either a
1352           coprocessor or this emulation.
1353
1354           If you don't have a math coprocessor, you need to say Y here; if you
1355           say Y here even though you have a coprocessor, the coprocessor will
1356           be used nevertheless. (This behavior can be changed with the kernel
1357           command line option "no387", which comes handy if your coprocessor
1358           is broken. Try "man bootparam" or see the documentation of your boot
1359           loader (lilo or loadlin) about how to pass options to the kernel at
1360           boot time.) This means that it is a good idea to say Y here if you
1361           intend to use this kernel on different machines.
1362
1363           More information about the internals of the Linux math coprocessor
1364           emulation can be found in <file:arch/x86/math-emu/README>.
1365
1366           If you are not sure, say Y; apart from resulting in a 66 KB bigger
1367           kernel, it won't hurt.
1368
1369 config MTRR
1370         def_bool y
1371         prompt "MTRR (Memory Type Range Register) support" if EMBEDDED
1372         ---help---
1373           On Intel P6 family processors (Pentium Pro, Pentium II and later)
1374           the Memory Type Range Registers (MTRRs) may be used to control
1375           processor access to memory ranges. This is most useful if you have
1376           a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1377           allows bus write transfers to be combined into a larger transfer
1378           before bursting over the PCI/AGP bus. This can increase performance
1379           of image write operations 2.5 times or more. Saying Y here creates a
1380           /proc/mtrr file which may be used to manipulate your processor's
1381           MTRRs. Typically the X server should use this.
1382
1383           This code has a reasonably generic interface so that similar
1384           control registers on other processors can be easily supported
1385           as well:
1386
1387           The Cyrix 6x86, 6x86MX and M II processors have Address Range
1388           Registers (ARRs) which provide a similar functionality to MTRRs. For
1389           these, the ARRs are used to emulate the MTRRs.
1390           The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1391           MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1392           write-combining. All of these processors are supported by this code
1393           and it makes sense to say Y here if you have one of them.
1394
1395           Saying Y here also fixes a problem with buggy SMP BIOSes which only
1396           set the MTRRs for the boot CPU and not for the secondary CPUs. This
1397           can lead to all sorts of problems, so it's good to say Y here.
1398
1399           You can safely say Y even if your machine doesn't have MTRRs, you'll
1400           just add about 9 KB to your kernel.
1401
1402           See <file:Documentation/x86/mtrr.txt> for more information.
1403
1404 config MTRR_SANITIZER
1405         def_bool y
1406         prompt "MTRR cleanup support"
1407         depends on MTRR
1408         ---help---
1409           Convert MTRR layout from continuous to discrete, so X drivers can
1410           add writeback entries.
1411
1412           Can be disabled with disable_mtrr_cleanup on the kernel command line.
1413           The largest mtrr entry size for a continuous block can be set with
1414           mtrr_chunk_size.
1415
1416           If unsure, say Y.
1417
1418 config MTRR_SANITIZER_ENABLE_DEFAULT
1419         int "MTRR cleanup enable value (0-1)"
1420         range 0 1
1421         default "0"
1422         depends on MTRR_SANITIZER
1423         ---help---
1424           Enable mtrr cleanup default value
1425
1426 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1427         int "MTRR cleanup spare reg num (0-7)"
1428         range 0 7
1429         default "1"
1430         depends on MTRR_SANITIZER
1431         ---help---
1432           mtrr cleanup spare entries default, it can be changed via
1433           mtrr_spare_reg_nr=N on the kernel command line.
1434
1435 config X86_PAT
1436         def_bool y
1437         prompt "x86 PAT support" if EMBEDDED
1438         depends on MTRR
1439         ---help---
1440           Use PAT attributes to setup page level cache control.
1441
1442           PATs are the modern equivalents of MTRRs and are much more
1443           flexible than MTRRs.
1444
1445           Say N here if you see bootup problems (boot crash, boot hang,
1446           spontaneous reboots) or a non-working video driver.
1447
1448           If unsure, say Y.
1449
1450 config ARCH_USES_PG_UNCACHED
1451         def_bool y
1452         depends on X86_PAT
1453
1454 config EFI
1455         bool "EFI runtime service support"
1456         depends on ACPI
1457         ---help---
1458           This enables the kernel to use EFI runtime services that are
1459           available (such as the EFI variable services).
1460
1461           This option is only useful on systems that have EFI firmware.
1462           In addition, you should use the latest ELILO loader available
1463           at <http://elilo.sourceforge.net> in order to take advantage
1464           of EFI runtime services. However, even with this option, the
1465           resultant kernel should continue to boot on existing non-EFI
1466           platforms.
1467
1468 config SECCOMP
1469         def_bool y
1470         prompt "Enable seccomp to safely compute untrusted bytecode"
1471         ---help---
1472           This kernel feature is useful for number crunching applications
1473           that may need to compute untrusted bytecode during their
1474           execution. By using pipes or other transports made available to
1475           the process as file descriptors supporting the read/write
1476           syscalls, it's possible to isolate those applications in
1477           their own address space using seccomp. Once seccomp is
1478           enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1479           and the task is only allowed to execute a few safe syscalls
1480           defined by each seccomp mode.
1481
1482           If unsure, say Y. Only embedded should say N here.
1483
1484 config CC_STACKPROTECTOR
1485         bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1486         ---help---
1487           This option turns on the -fstack-protector GCC feature. This
1488           feature puts, at the beginning of functions, a canary value on
1489           the stack just before the return address, and validates
1490           the value just before actually returning.  Stack based buffer
1491           overflows (that need to overwrite this return address) now also
1492           overwrite the canary, which gets detected and the attack is then
1493           neutralized via a kernel panic.
1494
1495           This feature requires gcc version 4.2 or above, or a distribution
1496           gcc with the feature backported. Older versions are automatically
1497           detected and for those versions, this configuration option is
1498           ignored. (and a warning is printed during bootup)
1499
1500 source kernel/Kconfig.hz
1501
1502 config KEXEC
1503         bool "kexec system call"
1504         ---help---
1505           kexec is a system call that implements the ability to shutdown your
1506           current kernel, and to start another kernel.  It is like a reboot
1507           but it is independent of the system firmware.   And like a reboot
1508           you can start any kernel with it, not just Linux.
1509
1510           The name comes from the similarity to the exec system call.
1511
1512           It is an ongoing process to be certain the hardware in a machine
1513           is properly shutdown, so do not be surprised if this code does not
1514           initially work for you.  It may help to enable device hotplugging
1515           support.  As of this writing the exact hardware interface is
1516           strongly in flux, so no good recommendation can be made.
1517
1518 config CRASH_DUMP
1519         bool "kernel crash dumps"
1520         depends on X86_64 || (X86_32 && HIGHMEM)
1521         ---help---
1522           Generate crash dump after being started by kexec.
1523           This should be normally only set in special crash dump kernels
1524           which are loaded in the main kernel with kexec-tools into
1525           a specially reserved region and then later executed after
1526           a crash by kdump/kexec. The crash dump kernel must be compiled
1527           to a memory address not used by the main kernel or BIOS using
1528           PHYSICAL_START, or it must be built as a relocatable image
1529           (CONFIG_RELOCATABLE=y).
1530           For more details see Documentation/kdump/kdump.txt
1531
1532 config KEXEC_JUMP
1533         bool "kexec jump (EXPERIMENTAL)"
1534         depends on EXPERIMENTAL
1535         depends on KEXEC && HIBERNATION
1536         ---help---
1537           Jump between original kernel and kexeced kernel and invoke
1538           code in physical address mode via KEXEC
1539
1540 config PHYSICAL_START
1541         hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1542         default "0x1000000"
1543         ---help---
1544           This gives the physical address where the kernel is loaded.
1545
1546           If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1547           bzImage will decompress itself to above physical address and
1548           run from there. Otherwise, bzImage will run from the address where
1549           it has been loaded by the boot loader and will ignore above physical
1550           address.
1551
1552           In normal kdump cases one does not have to set/change this option
1553           as now bzImage can be compiled as a completely relocatable image
1554           (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1555           address. This option is mainly useful for the folks who don't want
1556           to use a bzImage for capturing the crash dump and want to use a
1557           vmlinux instead. vmlinux is not relocatable hence a kernel needs
1558           to be specifically compiled to run from a specific memory area
1559           (normally a reserved region) and this option comes handy.
1560
1561           So if you are using bzImage for capturing the crash dump,
1562           leave the value here unchanged to 0x1000000 and set
1563           CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
1564           for capturing the crash dump change this value to start of
1565           the reserved region.  In other words, it can be set based on
1566           the "X" value as specified in the "crashkernel=YM@XM"
1567           command line boot parameter passed to the panic-ed
1568           kernel. Please take a look at Documentation/kdump/kdump.txt
1569           for more details about crash dumps.
1570
1571           Usage of bzImage for capturing the crash dump is recommended as
1572           one does not have to build two kernels. Same kernel can be used
1573           as production kernel and capture kernel. Above option should have
1574           gone away after relocatable bzImage support is introduced. But it
1575           is present because there are users out there who continue to use
1576           vmlinux for dump capture. This option should go away down the
1577           line.
1578
1579           Don't change this unless you know what you are doing.
1580
1581 config RELOCATABLE
1582         bool "Build a relocatable kernel"
1583         default y
1584         ---help---
1585           This builds a kernel image that retains relocation information
1586           so it can be loaded someplace besides the default 1MB.
1587           The relocations tend to make the kernel binary about 10% larger,
1588           but are discarded at runtime.
1589
1590           One use is for the kexec on panic case where the recovery kernel
1591           must live at a different physical address than the primary
1592           kernel.
1593
1594           Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1595           it has been loaded at and the compile time physical address
1596           (CONFIG_PHYSICAL_START) is ignored.
1597
1598 # Relocation on x86-32 needs some additional build support
1599 config X86_NEED_RELOCS
1600         def_bool y
1601         depends on X86_32 && RELOCATABLE
1602
1603 config PHYSICAL_ALIGN
1604         hex "Alignment value to which kernel should be aligned" if X86_32
1605         default "0x1000000"
1606         range 0x2000 0x1000000
1607         ---help---
1608           This value puts the alignment restrictions on physical address
1609           where kernel is loaded and run from. Kernel is compiled for an
1610           address which meets above alignment restriction.
1611
1612           If bootloader loads the kernel at a non-aligned address and
1613           CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1614           address aligned to above value and run from there.
1615
1616           If bootloader loads the kernel at a non-aligned address and
1617           CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1618           load address and decompress itself to the address it has been
1619           compiled for and run from there. The address for which kernel is
1620           compiled already meets above alignment restrictions. Hence the
1621           end result is that kernel runs from a physical address meeting
1622           above alignment restrictions.
1623
1624           Don't change this unless you know what you are doing.
1625
1626 config HOTPLUG_CPU
1627         bool "Support for hot-pluggable CPUs"
1628         depends on SMP && HOTPLUG
1629         ---help---
1630           Say Y here to allow turning CPUs off and on. CPUs can be
1631           controlled through /sys/devices/system/cpu.
1632           ( Note: power management support will enable this option
1633             automatically on SMP systems. )
1634           Say N if you want to disable CPU hotplug.
1635
1636 config COMPAT_VDSO
1637         def_bool y
1638         prompt "Compat VDSO support"
1639         depends on X86_32 || IA32_EMULATION
1640         ---help---
1641           Map the 32-bit VDSO to the predictable old-style address too.
1642
1643           Say N here if you are running a sufficiently recent glibc
1644           version (2.3.3 or later), to remove the high-mapped
1645           VDSO mapping and to exclusively use the randomized VDSO.
1646
1647           If unsure, say Y.
1648
1649 config CMDLINE_BOOL
1650         bool "Built-in kernel command line"
1651         ---help---
1652           Allow for specifying boot arguments to the kernel at
1653           build time.  On some systems (e.g. embedded ones), it is
1654           necessary or convenient to provide some or all of the
1655           kernel boot arguments with the kernel itself (that is,
1656           to not rely on the boot loader to provide them.)
1657
1658           To compile command line arguments into the kernel,
1659           set this option to 'Y', then fill in the
1660           the boot arguments in CONFIG_CMDLINE.
1661
1662           Systems with fully functional boot loaders (i.e. non-embedded)
1663           should leave this option set to 'N'.
1664
1665 config CMDLINE
1666         string "Built-in kernel command string"
1667         depends on CMDLINE_BOOL
1668         default ""
1669         ---help---
1670           Enter arguments here that should be compiled into the kernel
1671           image and used at boot time.  If the boot loader provides a
1672           command line at boot time, it is appended to this string to
1673           form the full kernel command line, when the system boots.
1674
1675           However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1676           change this behavior.
1677
1678           In most cases, the command line (whether built-in or provided
1679           by the boot loader) should specify the device for the root
1680           file system.
1681
1682 config CMDLINE_OVERRIDE
1683         bool "Built-in command line overrides boot loader arguments"
1684         depends on CMDLINE_BOOL
1685         ---help---
1686           Set this option to 'Y' to have the kernel ignore the boot loader
1687           command line, and use ONLY the built-in command line.
1688
1689           This is used to work around broken boot loaders.  This should
1690           be set to 'N' under normal conditions.
1691
1692 endmenu
1693
1694 config ARCH_ENABLE_MEMORY_HOTPLUG
1695         def_bool y
1696         depends on X86_64 || (X86_32 && HIGHMEM)
1697
1698 config ARCH_ENABLE_MEMORY_HOTREMOVE
1699         def_bool y
1700         depends on MEMORY_HOTPLUG
1701
1702 config HAVE_ARCH_EARLY_PFN_TO_NID
1703         def_bool X86_64
1704         depends on NUMA
1705
1706 menu "Power management and ACPI options"
1707
1708 config ARCH_HIBERNATION_HEADER
1709         def_bool y
1710         depends on X86_64 && HIBERNATION
1711
1712 source "kernel/power/Kconfig"
1713
1714 source "drivers/acpi/Kconfig"
1715
1716 source "drivers/sfi/Kconfig"
1717
1718 config X86_APM_BOOT
1719         def_bool y
1720         depends on APM || APM_MODULE
1721
1722 menuconfig APM
1723         tristate "APM (Advanced Power Management) BIOS support"
1724         depends on X86_32 && PM_SLEEP
1725         ---help---
1726           APM is a BIOS specification for saving power using several different
1727           techniques. This is mostly useful for battery powered laptops with
1728           APM compliant BIOSes. If you say Y here, the system time will be
1729           reset after a RESUME operation, the /proc/apm device will provide
1730           battery status information, and user-space programs will receive
1731           notification of APM "events" (e.g. battery status change).
1732
1733           If you select "Y" here, you can disable actual use of the APM
1734           BIOS by passing the "apm=off" option to the kernel at boot time.
1735
1736           Note that the APM support is almost completely disabled for
1737           machines with more than one CPU.
1738
1739           In order to use APM, you will need supporting software. For location
1740           and more information, read <file:Documentation/power/pm.txt> and the
1741           Battery Powered Linux mini-HOWTO, available from
1742           <http://www.tldp.org/docs.html#howto>.
1743
1744           This driver does not spin down disk drives (see the hdparm(8)
1745           manpage ("man 8 hdparm") for that), and it doesn't turn off
1746           VESA-compliant "green" monitors.
1747
1748           This driver does not support the TI 4000M TravelMate and the ACER
1749           486/DX4/75 because they don't have compliant BIOSes. Many "green"
1750           desktop machines also don't have compliant BIOSes, and this driver
1751           may cause those machines to panic during the boot phase.
1752
1753           Generally, if you don't have a battery in your machine, there isn't
1754           much point in using this driver and you should say N. If you get
1755           random kernel OOPSes or reboots that don't seem to be related to
1756           anything, try disabling/enabling this option (or disabling/enabling
1757           APM in your BIOS).
1758
1759           Some other things you should try when experiencing seemingly random,
1760           "weird" problems:
1761
1762           1) make sure that you have enough swap space and that it is
1763           enabled.
1764           2) pass the "no-hlt" option to the kernel
1765           3) switch on floating point emulation in the kernel and pass
1766           the "no387" option to the kernel
1767           4) pass the "floppy=nodma" option to the kernel
1768           5) pass the "mem=4M" option to the kernel (thereby disabling
1769           all but the first 4 MB of RAM)
1770           6) make sure that the CPU is not over clocked.
1771           7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1772           8) disable the cache from your BIOS settings
1773           9) install a fan for the video card or exchange video RAM
1774           10) install a better fan for the CPU
1775           11) exchange RAM chips
1776           12) exchange the motherboard.
1777
1778           To compile this driver as a module, choose M here: the
1779           module will be called apm.
1780
1781 if APM
1782
1783 config APM_IGNORE_USER_SUSPEND
1784         bool "Ignore USER SUSPEND"
1785         ---help---
1786           This option will ignore USER SUSPEND requests. On machines with a
1787           compliant APM BIOS, you want to say N. However, on the NEC Versa M
1788           series notebooks, it is necessary to say Y because of a BIOS bug.
1789
1790 config APM_DO_ENABLE
1791         bool "Enable PM at boot time"
1792         ---help---
1793           Enable APM features at boot time. From page 36 of the APM BIOS
1794           specification: "When disabled, the APM BIOS does not automatically
1795           power manage devices, enter the Standby State, enter the Suspend
1796           State, or take power saving steps in response to CPU Idle calls."
1797           This driver will make CPU Idle calls when Linux is idle (unless this
1798           feature is turned off -- see "Do CPU IDLE calls", below). This
1799           should always save battery power, but more complicated APM features
1800           will be dependent on your BIOS implementation. You may need to turn
1801           this option off if your computer hangs at boot time when using APM
1802           support, or if it beeps continuously instead of suspending. Turn
1803           this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1804           T400CDT. This is off by default since most machines do fine without
1805           this feature.
1806
1807 config APM_CPU_IDLE
1808         bool "Make CPU Idle calls when idle"
1809         ---help---
1810           Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1811           On some machines, this can activate improved power savings, such as
1812           a slowed CPU clock rate, when the machine is idle. These idle calls
1813           are made after the idle loop has run for some length of time (e.g.,
1814           333 mS). On some machines, this will cause a hang at boot time or
1815           whenever the CPU becomes idle. (On machines with more than one CPU,
1816           this option does nothing.)
1817
1818 config APM_DISPLAY_BLANK
1819         bool "Enable console blanking using APM"
1820         ---help---
1821           Enable console blanking using the APM. Some laptops can use this to
1822           turn off the LCD backlight when the screen blanker of the Linux
1823           virtual console blanks the screen. Note that this is only used by
1824           the virtual console screen blanker, and won't turn off the backlight
1825           when using the X Window system. This also doesn't have anything to
1826           do with your VESA-compliant power-saving monitor. Further, this
1827           option doesn't work for all laptops -- it might not turn off your
1828           backlight at all, or it might print a lot of errors to the console,
1829           especially if you are using gpm.
1830
1831 config APM_ALLOW_INTS
1832         bool "Allow interrupts during APM BIOS calls"
1833         ---help---
1834           Normally we disable external interrupts while we are making calls to
1835           the APM BIOS as a measure to lessen the effects of a badly behaving
1836           BIOS implementation.  The BIOS should reenable interrupts if it
1837           needs to.  Unfortunately, some BIOSes do not -- especially those in
1838           many of the newer IBM Thinkpads.  If you experience hangs when you
1839           suspend, try setting this to Y.  Otherwise, say N.
1840
1841 endif # APM
1842
1843 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1844
1845 source "drivers/cpuidle/Kconfig"
1846
1847 source "drivers/idle/Kconfig"
1848
1849 endmenu
1850
1851
1852 menu "Bus options (PCI etc.)"
1853
1854 config PCI
1855         bool "PCI support"
1856         default y
1857         select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1858         ---help---
1859           Find out whether you have a PCI motherboard. PCI is the name of a
1860           bus system, i.e. the way the CPU talks to the other stuff inside
1861           your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1862           VESA. If you have PCI, say Y, otherwise N.
1863
1864 choice
1865         prompt "PCI access mode"
1866         depends on X86_32 && PCI
1867         default PCI_GOANY
1868         ---help---
1869           On PCI systems, the BIOS can be used to detect the PCI devices and
1870           determine their configuration. However, some old PCI motherboards
1871           have BIOS bugs and may crash if this is done. Also, some embedded
1872           PCI-based systems don't have any BIOS at all. Linux can also try to
1873           detect the PCI hardware directly without using the BIOS.
1874
1875           With this option, you can specify how Linux should detect the
1876           PCI devices. If you choose "BIOS", the BIOS will be used,
1877           if you choose "Direct", the BIOS won't be used, and if you
1878           choose "MMConfig", then PCI Express MMCONFIG will be used.
1879           If you choose "Any", the kernel will try MMCONFIG, then the
1880           direct access method and falls back to the BIOS if that doesn't
1881           work. If unsure, go with the default, which is "Any".
1882
1883 config PCI_GOBIOS
1884         bool "BIOS"
1885
1886 config PCI_GOMMCONFIG
1887         bool "MMConfig"
1888
1889 config PCI_GODIRECT
1890         bool "Direct"
1891
1892 config PCI_GOOLPC
1893         bool "OLPC"
1894         depends on OLPC
1895
1896 config PCI_GOANY
1897         bool "Any"
1898
1899 endchoice
1900
1901 config PCI_BIOS
1902         def_bool y
1903         depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1904
1905 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1906 config PCI_DIRECT
1907         def_bool y
1908         depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1909
1910 config PCI_MMCONFIG
1911         def_bool y
1912         depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
1913
1914 config PCI_OLPC
1915         def_bool y
1916         depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1917
1918 config PCI_DOMAINS
1919         def_bool y
1920         depends on PCI
1921
1922 config PCI_MMCONFIG
1923         bool "Support mmconfig PCI config space access"
1924         depends on X86_64 && PCI && ACPI
1925
1926 config PCI_CNB20LE_QUIRK
1927         bool "Read CNB20LE Host Bridge Windows"
1928         depends on PCI
1929         help
1930           Read the PCI windows out of the CNB20LE host bridge. This allows
1931           PCI hotplug to work on systems with the CNB20LE chipset which do
1932           not have ACPI.
1933
1934 config DMAR
1935         bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1936         depends on PCI_MSI && ACPI && EXPERIMENTAL
1937         help
1938           DMA remapping (DMAR) devices support enables independent address
1939           translations for Direct Memory Access (DMA) from devices.
1940           These DMA remapping devices are reported via ACPI tables
1941           and include PCI device scope covered by these DMA
1942           remapping devices.
1943
1944 config DMAR_DEFAULT_ON
1945         def_bool y
1946         prompt "Enable DMA Remapping Devices by default"
1947         depends on DMAR
1948         help
1949           Selecting this option will enable a DMAR device at boot time if
1950           one is found. If this option is not selected, DMAR support can
1951           be enabled by passing intel_iommu=on to the kernel. It is
1952           recommended you say N here while the DMAR code remains
1953           experimental.
1954
1955 config DMAR_BROKEN_GFX_WA
1956         bool "Workaround broken graphics drivers (going away soon)"
1957         depends on DMAR && BROKEN
1958         ---help---
1959           Current Graphics drivers tend to use physical address
1960           for DMA and avoid using DMA APIs. Setting this config
1961           option permits the IOMMU driver to set a unity map for
1962           all the OS-visible memory. Hence the driver can continue
1963           to use physical addresses for DMA, at least until this
1964           option is removed in the 2.6.32 kernel.
1965
1966 config DMAR_FLOPPY_WA
1967         def_bool y
1968         depends on DMAR
1969         ---help---
1970           Floppy disk drivers are known to bypass DMA API calls
1971           thereby failing to work when IOMMU is enabled. This
1972           workaround will setup a 1:1 mapping for the first
1973           16MiB to make floppy (an ISA device) work.
1974
1975 config INTR_REMAP
1976         bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1977         depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
1978         ---help---
1979           Supports Interrupt remapping for IO-APIC and MSI devices.
1980           To use x2apic mode in the CPU's which support x2APIC enhancements or
1981           to support platforms with CPU's having > 8 bit APIC ID, say Y.
1982
1983 source "drivers/pci/pcie/Kconfig"
1984
1985 source "drivers/pci/Kconfig"
1986
1987 # x86_64 have no ISA slots, but do have ISA-style DMA.
1988 config ISA_DMA_API
1989         def_bool y
1990
1991 if X86_32
1992
1993 config ISA
1994         bool "ISA support"
1995         ---help---
1996           Find out whether you have ISA slots on your motherboard.  ISA is the
1997           name of a bus system, i.e. the way the CPU talks to the other stuff
1998           inside your box.  Other bus systems are PCI, EISA, MicroChannel
1999           (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
2000           newer boards don't support it.  If you have ISA, say Y, otherwise N.
2001
2002 config EISA
2003         bool "EISA support"
2004         depends on ISA
2005         ---help---
2006           The Extended Industry Standard Architecture (EISA) bus was
2007           developed as an open alternative to the IBM MicroChannel bus.
2008
2009           The EISA bus provided some of the features of the IBM MicroChannel
2010           bus while maintaining backward compatibility with cards made for
2011           the older ISA bus.  The EISA bus saw limited use between 1988 and
2012           1995 when it was made obsolete by the PCI bus.
2013
2014           Say Y here if you are building a kernel for an EISA-based machine.
2015
2016           Otherwise, say N.
2017
2018 source "drivers/eisa/Kconfig"
2019
2020 config MCA
2021         bool "MCA support"
2022         ---help---
2023           MicroChannel Architecture is found in some IBM PS/2 machines and
2024           laptops.  It is a bus system similar to PCI or ISA. See
2025           <file:Documentation/mca.txt> (and especially the web page given
2026           there) before attempting to build an MCA bus kernel.
2027
2028 source "drivers/mca/Kconfig"
2029
2030 config SCx200
2031         tristate "NatSemi SCx200 support"
2032         ---help---
2033           This provides basic support for National Semiconductor's
2034           (now AMD's) Geode processors.  The driver probes for the
2035           PCI-IDs of several on-chip devices, so its a good dependency
2036           for other scx200_* drivers.
2037
2038           If compiled as a module, the driver is named scx200.
2039
2040 config SCx200HR_TIMER
2041         tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2042         depends on SCx200 && GENERIC_TIME
2043         default y
2044         ---help---
2045           This driver provides a clocksource built upon the on-chip
2046           27MHz high-resolution timer.  Its also a workaround for
2047           NSC Geode SC-1100's buggy TSC, which loses time when the
2048           processor goes idle (as is done by the scheduler).  The
2049           other workaround is idle=poll boot option.
2050
2051 config OLPC
2052         bool "One Laptop Per Child support"
2053         select GPIOLIB
2054         ---help---
2055           Add support for detecting the unique features of the OLPC
2056           XO hardware.
2057
2058 endif # X86_32
2059
2060 config K8_NB
2061         def_bool y
2062         depends on CPU_SUP_AMD && PCI
2063
2064 source "drivers/pcmcia/Kconfig"
2065
2066 source "drivers/pci/hotplug/Kconfig"
2067
2068 endmenu
2069
2070
2071 menu "Executable file formats / Emulations"
2072
2073 source "fs/Kconfig.binfmt"
2074
2075 config IA32_EMULATION
2076         bool "IA32 Emulation"
2077         depends on X86_64
2078         select COMPAT_BINFMT_ELF
2079         ---help---
2080           Include code to run 32-bit programs under a 64-bit kernel. You should
2081           likely turn this on, unless you're 100% sure that you don't have any
2082           32-bit programs left.
2083
2084 config IA32_AOUT
2085         tristate "IA32 a.out support"
2086         depends on IA32_EMULATION
2087         ---help---
2088           Support old a.out binaries in the 32bit emulation.
2089
2090 config COMPAT
2091         def_bool y
2092         depends on IA32_EMULATION
2093
2094 config COMPAT_FOR_U64_ALIGNMENT
2095         def_bool COMPAT
2096         depends on X86_64
2097
2098 config SYSVIPC_COMPAT
2099         def_bool y
2100         depends on COMPAT && SYSVIPC
2101
2102 endmenu
2103
2104
2105 config HAVE_ATOMIC_IOMAP
2106         def_bool y
2107         depends on X86_32
2108
2109 source "net/Kconfig"
2110
2111 source "drivers/Kconfig"
2112
2113 source "drivers/firmware/Kconfig"
2114
2115 source "fs/Kconfig"
2116
2117 source "arch/x86/Kconfig.debug"
2118
2119 source "security/Kconfig"
2120
2121 source "crypto/Kconfig"
2122
2123 source "arch/x86/kvm/Kconfig"
2124
2125 source "lib/Kconfig"