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_DMA_API_DEBUG
  50         select HAVE_KERNEL_GZIP
  51         select HAVE_KERNEL_BZIP2
  52         select HAVE_KERNEL_LZMA
  53         select HAVE_KERNEL_LZO
  54         select HAVE_HW_BREAKPOINT
  55         select PERF_EVENTS
  56         select ANON_INODES
  57         select HAVE_ARCH_KMEMCHECK
  58         select HAVE_USER_RETURN_NOTIFIER
  59
  60 config OUTPUT_FORMAT
  61         string
  62         default "elf32-i386" if X86_32
  63         default "elf64-x86-64" if X86_64
  64
  65 config ARCH_DEFCONFIG
  66         string
  67         default "arch/x86/configs/i386_defconfig" if X86_32
  68         default "arch/x86/configs/x86_64_defconfig" if X86_64
  69
  70 config GENERIC_TIME
  71         def_bool y
  72
  73 config GENERIC_CMOS_UPDATE
  74         def_bool y
  75
  76 config CLOCKSOURCE_WATCHDOG
  77         def_bool y
  78
  79 config GENERIC_CLOCKEVENTS
  80         def_bool y
  81
  82 config GENERIC_CLOCKEVENTS_BROADCAST
  83         def_bool y
  84         depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  85
  86 config LOCKDEP_SUPPORT
  87         def_bool y
  88
  89 config STACKTRACE_SUPPORT
  90         def_bool y
  91
  92 config HAVE_LATENCYTOP_SUPPORT
  93         def_bool y
  94
  95 config MMU
  96         def_bool y
  97
  98 config ZONE_DMA
  99         def_bool y
 100
 101 config SBUS
 102         bool
 103
 104 config GENERIC_ISA_DMA
 105         def_bool y
 106
 107 config GENERIC_IOMAP
 108         def_bool y
 109
 110 config GENERIC_BUG
 111         def_bool y
 112         depends on BUG
 113         select GENERIC_BUG_RELATIVE_POINTERS if X86_64
 114
 115 config GENERIC_BUG_RELATIVE_POINTERS
 116         bool
 117
 118 config GENERIC_HWEIGHT
 119         def_bool y
 120
 121 config GENERIC_GPIO
 122         bool
 123
 124 config ARCH_MAY_HAVE_PC_FDC
 125         def_bool y
 126
 127 config RWSEM_GENERIC_SPINLOCK
 128         def_bool !X86_XADD
 129
 130 config RWSEM_XCHGADD_ALGORITHM
 131         def_bool X86_XADD
 132
 133 config ARCH_HAS_CPU_IDLE_WAIT
 134         def_bool y
 135
 136 config GENERIC_CALIBRATE_DELAY
 137         def_bool y
 138
 139 config GENERIC_TIME_VSYSCALL
 140         bool
 141         default X86_64
 142
 143 config ARCH_HAS_CPU_RELAX
 144         def_bool y
 145
 146 config ARCH_HAS_DEFAULT_IDLE
 147         def_bool y
 148
 149 config ARCH_HAS_CACHE_LINE_SIZE
 150         def_bool y
 151
 152 config HAVE_SETUP_PER_CPU_AREA
 153         def_bool y
 154
 155 config NEED_PER_CPU_EMBED_FIRST_CHUNK
 156         def_bool y
 157
 158 config NEED_PER_CPU_PAGE_FIRST_CHUNK
 159         def_bool y
 160
 161 config HAVE_CPUMASK_OF_CPU_MAP
 162         def_bool X86_64_SMP
 163
 164 config ARCH_HIBERNATION_POSSIBLE
 165         def_bool y
 166
 167 config ARCH_SUSPEND_POSSIBLE
 168         def_bool y
 169
 170 config ZONE_DMA32
 171         bool
 172         default X86_64
 173
 174 config ARCH_POPULATES_NODE_MAP
 175         def_bool y
 176
 177 config AUDIT_ARCH
 178         bool
 179         default X86_64
 180
 181 config ARCH_SUPPORTS_OPTIMIZED_INLINING
 182         def_bool y
 183
 184 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
 185         def_bool y
 186
 187 config HAVE_INTEL_TXT
 188         def_bool y
 189         depends on EXPERIMENTAL && DMAR && ACPI
 190
 191 # Use the generic interrupt handling code in kernel/irq/:
 192 config GENERIC_HARDIRQS
 193         bool
 194         default y
 195
 196 config GENERIC_HARDIRQS_NO__DO_IRQ
 197        def_bool y
 198
 199 config GENERIC_IRQ_PROBE
 200         bool
 201         default y
 202
 203 config GENERIC_PENDING_IRQ
 204         bool
 205         depends on GENERIC_HARDIRQS && SMP
 206         default y
 207
 208 config USE_GENERIC_SMP_HELPERS
 209         def_bool y
 210         depends on SMP
 211
 212 config X86_32_SMP
 213         def_bool y
 214         depends on X86_32 && SMP
 215
 216 config X86_64_SMP
 217         def_bool y
 218         depends on X86_64 && SMP
 219
 220 config X86_HT
 221         bool
 222         depends on SMP
 223         default y
 224
 225 config X86_TRAMPOLINE
 226         bool
 227         depends on SMP || (64BIT && ACPI_SLEEP)
 228         default y
 229
 230 config X86_32_LAZY_GS
 231         def_bool y
 232         depends on X86_32 && !CC_STACKPROTECTOR
 233
 234 config KTIME_SCALAR
 235         def_bool X86_32
 236 source "init/Kconfig"
 237 source "kernel/Kconfig.freezer"
 238
 239 menu "Processor type and features"
 240
 241 source "kernel/time/Kconfig"
 242
 243 config SMP
 244         bool "Symmetric multi-processing support"
 245         ---help---
 246           This enables support for systems with more than one CPU. If you have
 247           a system with only one CPU, like most personal computers, say N. If
 248           you have a system with more than one CPU, say Y.
 249
 250           If you say N here, the kernel will run on single and multiprocessor
 251           machines, but will use only one CPU of a multiprocessor machine. If
 252           you say Y here, the kernel will run on many, but not all,
 253           singleprocessor machines. On a singleprocessor machine, the kernel
 254           will run faster if you say N here.
 255
 256           Note that if you say Y here and choose architecture "586" or
 257           "Pentium" under "Processor family", the kernel will not work on 486
 258           architectures. Similarly, multiprocessor kernels for the "PPro"
 259           architecture may not work on all Pentium based boards.
 260
 261           People using multiprocessor machines who say Y here should also say
 262           Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
 263           Management" code will be disabled if you say Y here.
 264
 265           See also <file:Documentation/i386/IO-APIC.txt>,
 266           <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
 267           <http://www.tldp.org/docs.html#howto>.
 268
 269           If you don't know what to do here, say N.
 270
 271 config X86_X2APIC
 272         bool "Support x2apic"
 273         depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
 274         ---help---
 275           This enables x2apic support on CPUs that have this feature.
 276
 277           This allows 32-bit apic IDs (so it can support very large systems),
 278           and accesses the local apic via MSRs not via mmio.
 279
 280           If you don't know what to do here, say N.
 281
 282 config SPARSE_IRQ
 283         bool "Support sparse irq numbering"
 284         depends on PCI_MSI || HT_IRQ
 285         ---help---
 286           This enables support for sparse irqs. This is useful for distro
 287           kernels that want to define a high CONFIG_NR_CPUS value but still
 288           want to have low kernel memory footprint on smaller machines.
 289
 290           ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
 291             out the irq_desc[] array in a more NUMA-friendly way. )
 292
 293           If you don't know what to do here, say N.
 294
 295 config NUMA_IRQ_DESC
 296         def_bool y
 297         depends on SPARSE_IRQ && NUMA
 298
 299 config X86_MPPARSE
 300         bool "Enable MPS table" if ACPI
 301         default y
 302         depends on X86_LOCAL_APIC
 303         ---help---
 304           For old smp systems that do not have proper acpi support. Newer systems
 305           (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
 306
 307 config X86_BIGSMP
 308         bool "Support for big SMP systems with more than 8 CPUs"
 309         depends on X86_32 && SMP
 310         ---help---
 311           This option is needed for the systems that have more than 8 CPUs
 312
 313 if X86_32
 314 config X86_EXTENDED_PLATFORM
 315         bool "Support for extended (non-PC) x86 platforms"
 316         default y
 317         ---help---
 318           If you disable this option then the kernel will only support
 319           standard PC platforms. (which covers the vast majority of
 320           systems out there.)
 321
 322           If you enable this option then you'll be able to select support
 323           for the following (non-PC) 32 bit x86 platforms:
 324                 AMD Elan
 325                 NUMAQ (IBM/Sequent)
 326                 RDC R-321x SoC
 327                 SGI 320/540 (Visual Workstation)
 328                 Summit/EXA (IBM x440)
 329                 Unisys ES7000 IA32 series
 330                 Moorestown MID devices
 331
 332           If you have one of these systems, or if you want to build a
 333           generic distribution kernel, say Y here - otherwise say N.
 334 endif
 335
 336 if X86_64
 337 config X86_EXTENDED_PLATFORM
 338         bool "Support for extended (non-PC) x86 platforms"
 339         default y
 340         ---help---
 341           If you disable this option then the kernel will only support
 342           standard PC platforms. (which covers the vast majority of
 343           systems out there.)
 344
 345           If you enable this option then you'll be able to select support
 346           for the following (non-PC) 64 bit x86 platforms:
 347                 ScaleMP vSMP
 348                 SGI Ultraviolet
 349
 350           If you have one of these systems, or if you want to build a
 351           generic distribution kernel, say Y here - otherwise say N.
 352 endif
 353 # This is an alphabetically sorted list of 64 bit extended platforms
 354 # Please maintain the alphabetic order if and when there are additions
 355
 356 config X86_VSMP
 357         bool "ScaleMP vSMP"
 358         select PARAVIRT
 359         depends on X86_64 && PCI
 360         depends on X86_EXTENDED_PLATFORM
 361         ---help---
 362           Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
 363           supposed to run on these EM64T-based machines.  Only choose this option
 364           if you have one of these machines.
 365
 366 config X86_UV
 367         bool "SGI Ultraviolet"
 368         depends on X86_64
 369         depends on X86_EXTENDED_PLATFORM
 370         depends on NUMA
 371         depends on X86_X2APIC
 372         ---help---
 373           This option is needed in order to support SGI Ultraviolet systems.
 374           If you don't have one of these, you should say N here.
 375
 376 # Following is an alphabetically sorted list of 32 bit extended platforms
 377 # Please maintain the alphabetic order if and when there are additions
 378
 379 config X86_ELAN
 380         bool "AMD Elan"
 381         depends on X86_32
 382         depends on X86_EXTENDED_PLATFORM
 383         ---help---
 384           Select this for an AMD Elan processor.
 385
 386           Do not use this option for K6/Athlon/Opteron processors!
 387
 388           If unsure, choose "PC-compatible" instead.
 389
 390 config X86_MRST
 391        bool "Moorestown MID platform"
 392         depends on X86_32
 393         depends on X86_EXTENDED_PLATFORM
 394         ---help---
 395           Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
 396           Internet Device(MID) platform. Moorestown consists of two chips:
 397           Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
 398           Unlike standard x86 PCs, Moorestown does not have many legacy devices
 399           nor standard legacy replacement devices/features. e.g. Moorestown does
 400           not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
 401
 402 config X86_RDC321X
 403         bool "RDC R-321x SoC"
 404         depends on X86_32
 405         depends on X86_EXTENDED_PLATFORM
 406         select M486
 407         select X86_REBOOTFIXUPS
 408         ---help---
 409           This option is needed for RDC R-321x system-on-chip, also known
 410           as R-8610-(G).
 411           If you don't have one of these chips, you should say N here.
 412
 413 config X86_32_NON_STANDARD
 414         bool "Support non-standard 32-bit SMP architectures"
 415         depends on X86_32 && SMP
 416         depends on X86_EXTENDED_PLATFORM
 417         ---help---
 418           This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
 419           subarchitectures.  It is intended for a generic binary kernel.
 420           if you select them all, kernel will probe it one by one. and will
 421           fallback to default.
 422
 423 # Alphabetically sorted list of Non standard 32 bit platforms
 424
 425 config X86_NUMAQ
 426         bool "NUMAQ (IBM/Sequent)"
 427         depends on X86_32_NON_STANDARD
 428         select NUMA
 429         select X86_MPPARSE
 430         ---help---
 431           This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
 432           NUMA multiquad box. This changes the way that processors are
 433           bootstrapped, and uses Clustered Logical APIC addressing mode instead
 434           of Flat Logical.  You will need a new lynxer.elf file to flash your
 435           firmware with - send email to <Martin.Bligh@us.ibm.com>.
 436
 437 config X86_SUPPORTS_MEMORY_FAILURE
 438         bool
 439         # MCE code calls memory_failure():
 440         depends on X86_MCE
 441         # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
 442         depends on !X86_NUMAQ
 443         # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
 444         depends on X86_64 || !SPARSEMEM
 445         select ARCH_SUPPORTS_MEMORY_FAILURE
 446         default y
 447
 448 config X86_VISWS
 449         bool "SGI 320/540 (Visual Workstation)"
 450         depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
 451         depends on X86_32_NON_STANDARD
 452         ---help---
 453           The SGI Visual Workstation series is an IA32-based workstation
 454           based on SGI systems chips with some legacy PC hardware attached.
 455
 456           Say Y here to create a kernel to run on the SGI 320 or 540.
 457
 458           A kernel compiled for the Visual Workstation will run on general
 459           PCs as well. See <file:Documentation/sgi-visws.txt> for details.
 460
 461 config X86_SUMMIT
 462         bool "Summit/EXA (IBM x440)"
 463         depends on X86_32_NON_STANDARD
 464         ---help---
 465           This option is needed for IBM systems that use the Summit/EXA chipset.
 466           In particular, it is needed for the x440.
 467
 468 config X86_ES7000
 469         bool "Unisys ES7000 IA32 series"
 470         depends on X86_32_NON_STANDARD && X86_BIGSMP
 471         ---help---
 472           Support for Unisys ES7000 systems.  Say 'Y' here if this kernel is
 473           supposed to run on an IA32-based Unisys ES7000 system.
 474
 475 config SCHED_OMIT_FRAME_POINTER
 476         def_bool y
 477         prompt "Single-depth WCHAN output"
 478         depends on X86
 479         ---help---
 480           Calculate simpler /proc/<PID>/wchan values. If this option
 481           is disabled then wchan values will recurse back to the
 482           caller function. This provides more accurate wchan values,
 483           at the expense of slightly more scheduling overhead.
 484
 485           If in doubt, say "Y".
 486
 487 menuconfig PARAVIRT_GUEST
 488         bool "Paravirtualized guest support"
 489         ---help---
 490           Say Y here to get to see options related to running Linux under
 491           various hypervisors.  This option alone does not add any kernel code.
 492
 493           If you say N, all options in this submenu will be skipped and disabled.
 494
 495 if PARAVIRT_GUEST
 496
 497 source "arch/x86/xen/Kconfig"
 498
 499 config VMI
 500         bool "VMI Guest support (DEPRECATED)"
 501         select PARAVIRT
 502         depends on X86_32
 503         ---help---
 504           VMI provides a paravirtualized interface to the VMware ESX server
 505           (it could be used by other hypervisors in theory too, but is not
 506           at the moment), by linking the kernel to a GPL-ed ROM module
 507           provided by the hypervisor.
 508
 509           As of September 2009, VMware has started a phased retirement
 510           of this feature from VMware's products. Please see
 511           feature-removal-schedule.txt for details.  If you are
 512           planning to enable this option, please note that you cannot
 513           live migrate a VMI enabled VM to a future VMware product,
 514           which doesn't support VMI. So if you expect your kernel to
 515           seamlessly migrate to newer VMware products, keep this
 516           disabled.
 517
 518 config KVM_CLOCK
 519         bool "KVM paravirtualized clock"
 520         select PARAVIRT
 521         select PARAVIRT_CLOCK
 522         ---help---
 523           Turning on this option will allow you to run a paravirtualized clock
 524           when running over the KVM hypervisor. Instead of relying on a PIT
 525           (or probably other) emulation by the underlying device model, the host
 526           provides the guest with timing infrastructure such as time of day, and
 527           system time
 528
 529 config KVM_GUEST
 530         bool "KVM Guest support"
 531         select PARAVIRT
 532         ---help---
 533           This option enables various optimizations for running under the KVM
 534           hypervisor.
 535
 536 source "arch/x86/lguest/Kconfig"
 537
 538 config PARAVIRT
 539         bool "Enable paravirtualization code"
 540         ---help---
 541           This changes the kernel so it can modify itself when it is run
 542           under a hypervisor, potentially improving performance significantly
 543           over full virtualization.  However, when run without a hypervisor
 544           the kernel is theoretically slower and slightly larger.
 545
 546 config PARAVIRT_SPINLOCKS
 547         bool "Paravirtualization layer for spinlocks"
 548         depends on PARAVIRT && SMP && EXPERIMENTAL
 549         ---help---
 550           Paravirtualized spinlocks allow a pvops backend to replace the
 551           spinlock implementation with something virtualization-friendly
 552           (for example, block the virtual CPU rather than spinning).
 553
 554           Unfortunately the downside is an up to 5% performance hit on
 555           native kernels, with various workloads.
 556
 557           If you are unsure how to answer this question, answer N.
 558
 559 config PARAVIRT_CLOCK
 560         bool
 561         default n
 562
 563 endif
 564
 565 config PARAVIRT_DEBUG
 566         bool "paravirt-ops debugging"
 567         depends on PARAVIRT && DEBUG_KERNEL
 568         ---help---
 569           Enable to debug paravirt_ops internals.  Specifically, BUG if
 570           a paravirt_op is missing when it is called.
 571
 572 config MEMTEST
 573         bool "Memtest"
 574         ---help---
 575           This option adds a kernel parameter 'memtest', which allows memtest
 576           to be set.
 577                 memtest=0, mean disabled; -- default
 578                 memtest=1, mean do 1 test pattern;
 579                 ...
 580                 memtest=4, mean do 4 test patterns.
 581           If you are unsure how to answer this question, answer N.
 582
 583 config X86_SUMMIT_NUMA
 584         def_bool y
 585         depends on X86_32 && NUMA && X86_32_NON_STANDARD
 586
 587 config X86_CYCLONE_TIMER
 588         def_bool y
 589         depends on X86_32_NON_STANDARD
 590
 591 source "arch/x86/Kconfig.cpu"
 592
 593 config HPET_TIMER
 594         def_bool X86_64
 595         prompt "HPET Timer Support" if X86_32
 596         ---help---
 597           Use the IA-PC HPET (High Precision Event Timer) to manage
 598           time in preference to the PIT and RTC, if a HPET is
 599           present.
 600           HPET is the next generation timer replacing legacy 8254s.
 601           The HPET provides a stable time base on SMP
 602           systems, unlike the TSC, but it is more expensive to access,
 603           as it is off-chip.  You can find the HPET spec at
 604           <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
 605
 606           You can safely choose Y here.  However, HPET will only be
 607           activated if the platform and the BIOS support this feature.
 608           Otherwise the 8254 will be used for timing services.
 609
 610           Choose N to continue using the legacy 8254 timer.
 611
 612 config HPET_EMULATE_RTC
 613         def_bool y
 614         depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
 615
 616 # Mark as embedded because too many people got it wrong.
 617 # The code disables itself when not needed.
 618 config DMI
 619         default y
 620         bool "Enable DMI scanning" if EMBEDDED
 621         ---help---
 622           Enabled scanning of DMI to identify machine quirks. Say Y
 623           here unless you have verified that your setup is not
 624           affected by entries in the DMI blacklist. Required by PNP
 625           BIOS code.
 626
 627 config GART_IOMMU
 628         bool "GART IOMMU support" if EMBEDDED
 629         default y
 630         select SWIOTLB
 631         depends on X86_64 && PCI
 632         ---help---
 633           Support for full DMA access of devices with 32bit memory access only
 634           on systems with more than 3GB. This is usually needed for USB,
 635           sound, many IDE/SATA chipsets and some other devices.
 636           Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
 637           based hardware IOMMU and a software bounce buffer based IOMMU used
 638           on Intel systems and as fallback.
 639           The code is only active when needed (enough memory and limited
 640           device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
 641           too.
 642
 643 config CALGARY_IOMMU
 644         bool "IBM Calgary IOMMU support"
 645         select SWIOTLB
 646         depends on X86_64 && PCI && EXPERIMENTAL
 647         ---help---
 648           Support for hardware IOMMUs in IBM's xSeries x366 and x460
 649           systems. Needed to run systems with more than 3GB of memory
 650           properly with 32-bit PCI devices that do not support DAC
 651           (Double Address Cycle). Calgary also supports bus level
 652           isolation, where all DMAs pass through the IOMMU.  This
 653           prevents them from going anywhere except their intended
 654           destination. This catches hard-to-find kernel bugs and
 655           mis-behaving drivers and devices that do not use the DMA-API
 656           properly to set up their DMA buffers.  The IOMMU can be
 657           turned off at boot time with the iommu=off parameter.
 658           Normally the kernel will make the right choice by itself.
 659           If unsure, say Y.
 660
 661 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
 662         def_bool y
 663         prompt "Should Calgary be enabled by default?"
 664         depends on CALGARY_IOMMU
 665         ---help---
 666           Should Calgary be enabled by default? if you choose 'y', Calgary
 667           will be used (if it exists). If you choose 'n', Calgary will not be
 668           used even if it exists. If you choose 'n' and would like to use
 669           Calgary anyway, pass 'iommu=calgary' on the kernel command line.
 670           If unsure, say Y.
 671
 672 config AMD_IOMMU
 673         bool "AMD IOMMU support"
 674         select SWIOTLB
 675         select PCI_MSI
 676         depends on X86_64 && PCI && ACPI
 677         ---help---
 678           With this option you can enable support for AMD IOMMU hardware in
 679           your system. An IOMMU is a hardware component which provides
 680           remapping of DMA memory accesses from devices. With an AMD IOMMU you
 681           can isolate the the DMA memory of different devices and protect the
 682           system from misbehaving device drivers or hardware.
 683
 684           You can find out if your system has an AMD IOMMU if you look into
 685           your BIOS for an option to enable it or if you have an IVRS ACPI
 686           table.
 687
 688 config AMD_IOMMU_STATS
 689         bool "Export AMD IOMMU statistics to debugfs"
 690         depends on AMD_IOMMU
 691         select DEBUG_FS
 692         ---help---
 693           This option enables code in the AMD IOMMU driver to collect various
 694           statistics about whats happening in the driver and exports that
 695           information to userspace via debugfs.
 696           If unsure, say N.
 697
 698 # need this always selected by IOMMU for the VIA workaround
 699 config SWIOTLB
 700         def_bool y if X86_64
 701         ---help---
 702           Support for software bounce buffers used on x86-64 systems
 703           which don't have a hardware IOMMU (e.g. the current generation
 704           of Intel's x86-64 CPUs). Using this PCI devices which can only
 705           access 32-bits of memory can be used on systems with more than
 706           3 GB of memory. If unsure, say Y.
 707
 708 config IOMMU_HELPER
 709         def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
 710
 711 config IOMMU_API
 712         def_bool (AMD_IOMMU || DMAR)
 713
 714 config MAXSMP
 715         bool "Configure Maximum number of SMP Processors and NUMA Nodes"
 716         depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
 717         select CPUMASK_OFFSTACK
 718         default n
 719         ---help---
 720           Configure maximum number of CPUS and NUMA Nodes for this architecture.
 721           If unsure, say N.
 722
 723 config NR_CPUS
 724         int "Maximum number of CPUs" if SMP && !MAXSMP
 725         range 2 8 if SMP && X86_32 && !X86_BIGSMP
 726         range 2 512 if SMP && !MAXSMP
 727         default "1" if !SMP
 728         default "4096" if MAXSMP
 729         default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
 730         default "8" if SMP
 731         ---help---
 732           This allows you to specify the maximum number of CPUs which this
 733           kernel will support.  The maximum supported value is 512 and the
 734           minimum value which makes sense is 2.
 735
 736           This is purely to save memory - each supported CPU adds
 737           approximately eight kilobytes to the kernel image.
 738
 739 config SCHED_SMT
 740         bool "SMT (Hyperthreading) scheduler support"
 741         depends on X86_HT
 742         ---help---
 743           SMT scheduler support improves the CPU scheduler's decision making
 744           when dealing with Intel Pentium 4 chips with HyperThreading at a
 745           cost of slightly increased overhead in some places. If unsure say
 746           N here.
 747
 748 config SCHED_MC
 749         def_bool y
 750         prompt "Multi-core scheduler support"
 751         depends on X86_HT
 752         ---help---
 753           Multi-core scheduler support improves the CPU scheduler's decision
 754           making when dealing with multi-core CPU chips at a cost of slightly
 755           increased overhead in some places. If unsure say N here.
 756
 757 source "kernel/Kconfig.preempt"
 758
 759 config X86_UP_APIC
 760         bool "Local APIC support on uniprocessors"
 761         depends on X86_32 && !SMP && !X86_32_NON_STANDARD
 762         ---help---
 763           A local APIC (Advanced Programmable Interrupt Controller) is an
 764           integrated interrupt controller in the CPU. If you have a single-CPU
 765           system which has a processor with a local APIC, you can say Y here to
 766           enable and use it. If you say Y here even though your machine doesn't
 767           have a local APIC, then the kernel will still run with no slowdown at
 768           all. The local APIC supports CPU-generated self-interrupts (timer,
 769           performance counters), and the NMI watchdog which detects hard
 770           lockups.
 771
 772 config X86_UP_IOAPIC
 773         bool "IO-APIC support on uniprocessors"
 774         depends on X86_UP_APIC
 775         ---help---
 776           An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
 777           SMP-capable replacement for PC-style interrupt controllers. Most
 778           SMP systems and many recent uniprocessor systems have one.
 779
 780           If you have a single-CPU system with an IO-APIC, you can say Y here
 781           to use it. If you say Y here even though your machine doesn't have
 782           an IO-APIC, then the kernel will still run with no slowdown at all.
 783
 784 config X86_LOCAL_APIC
 785         def_bool y
 786         depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
 787
 788 config X86_IO_APIC
 789         def_bool y
 790         depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
 791
 792 config X86_VISWS_APIC
 793         def_bool y
 794         depends on X86_32 && X86_VISWS
 795
 796 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
 797         bool "Reroute for broken boot IRQs"
 798         default n
 799         depends on X86_IO_APIC
 800         ---help---
 801           This option enables a workaround that fixes a source of
 802           spurious interrupts. This is recommended when threaded
 803           interrupt handling is used on systems where the generation of
 804           superfluous "boot interrupts" cannot be disabled.
 805
 806           Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
 807           entry in the chipset's IO-APIC is masked (as, e.g. the RT
 808           kernel does during interrupt handling). On chipsets where this
 809           boot IRQ generation cannot be disabled, this workaround keeps
 810           the original IRQ line masked so that only the equivalent "boot
 811           IRQ" is delivered to the CPUs. The workaround also tells the
 812           kernel to set up the IRQ handler on the boot IRQ line. In this
 813           way only one interrupt is delivered to the kernel. Otherwise
 814           the spurious second interrupt may cause the kernel to bring
 815           down (vital) interrupt lines.
 816
 817           Only affects "broken" chipsets. Interrupt sharing may be
 818           increased on these systems.
 819
 820 config X86_MCE
 821         bool "Machine Check / overheating reporting"
 822         ---help---
 823           Machine Check support allows the processor to notify the
 824           kernel if it detects a problem (e.g. overheating, data corruption).
 825           The action the kernel takes depends on the severity of the problem,
 826           ranging from warning messages to halting the machine.
 827
 828 config X86_MCE_INTEL
 829         def_bool y
 830         prompt "Intel MCE features"
 831         depends on X86_MCE && X86_LOCAL_APIC
 832         ---help---
 833            Additional support for intel specific MCE features such as
 834            the thermal monitor.
 835
 836 config X86_MCE_AMD
 837         def_bool y
 838         prompt "AMD MCE features"
 839         depends on X86_MCE && X86_LOCAL_APIC
 840         ---help---
 841            Additional support for AMD specific MCE features such as
 842            the DRAM Error Threshold.
 843
 844 config X86_ANCIENT_MCE
 845         def_bool n
 846         depends on X86_32 && X86_MCE
 847         prompt "Support for old Pentium 5 / WinChip machine checks"
 848         ---help---
 849           Include support for machine check handling on old Pentium 5 or WinChip
 850           systems. These typically need to be enabled explicitely on the command
 851           line.
 852
 853 config X86_MCE_THRESHOLD
 854         depends on X86_MCE_AMD || X86_MCE_INTEL
 855         bool
 856         default y
 857
 858 config X86_MCE_INJECT
 859         depends on X86_MCE
 860         tristate "Machine check injector support"
 861         ---help---
 862           Provide support for injecting machine checks for testing purposes.
 863           If you don't know what a machine check is and you don't do kernel
 864           QA it is safe to say n.
 865
 866 config X86_THERMAL_VECTOR
 867         def_bool y
 868         depends on X86_MCE_INTEL
 869
 870 config VM86
 871         bool "Enable VM86 support" if EMBEDDED
 872         default y
 873         depends on X86_32
 874         ---help---
 875           This option is required by programs like DOSEMU to run 16-bit legacy
 876           code on X86 processors. It also may be needed by software like
 877           XFree86 to initialize some video cards via BIOS. Disabling this
 878           option saves about 6k.
 879
 880 config TOSHIBA
 881         tristate "Toshiba Laptop support"
 882         depends on X86_32
 883         ---help---
 884           This adds a driver to safely access the System Management Mode of
 885           the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
 886           not work on models with a Phoenix BIOS. The System Management Mode
 887           is used to set the BIOS and power saving options on Toshiba portables.
 888
 889           For information on utilities to make use of this driver see the
 890           Toshiba Linux utilities web site at:
 891           <http://www.buzzard.org.uk/toshiba/>.
 892
 893           Say Y if you intend to run this kernel on a Toshiba portable.
 894           Say N otherwise.
 895
 896 config I8K
 897         tristate "Dell laptop support"
 898         ---help---
 899           This adds a driver to safely access the System Management Mode
 900           of the CPU on the Dell Inspiron 8000. The System Management Mode
 901           is used to read cpu temperature and cooling fan status and to
 902           control the fans on the I8K portables.
 903
 904           This driver has been tested only on the Inspiron 8000 but it may
 905           also work with other Dell laptops. You can force loading on other
 906           models by passing the parameter `force=1' to the module. Use at
 907           your own risk.
 908
 909           For information on utilities to make use of this driver see the
 910           I8K Linux utilities web site at:
 911           <http://people.debian.org/~dz/i8k/>
 912
 913           Say Y if you intend to run this kernel on a Dell Inspiron 8000.
 914           Say N otherwise.
 915
 916 config X86_REBOOTFIXUPS
 917         bool "Enable X86 board specific fixups for reboot"
 918         depends on X86_32
 919         ---help---
 920           This enables chipset and/or board specific fixups to be done
 921           in order to get reboot to work correctly. This is only needed on
 922           some combinations of hardware and BIOS. The symptom, for which
 923           this config is intended, is when reboot ends with a stalled/hung
 924           system.
 925
 926           Currently, the only fixup is for the Geode machines using
 927           CS5530A and CS5536 chipsets and the RDC R-321x SoC.
 928
 929           Say Y if you want to enable the fixup. Currently, it's safe to
 930           enable this option even if you don't need it.
 931           Say N otherwise.
 932
 933 config MICROCODE
 934         tristate "/dev/cpu/microcode - microcode support"
 935         select FW_LOADER
 936         ---help---
 937           If you say Y here, you will be able to update the microcode on
 938           certain Intel and AMD processors. The Intel support is for the
 939           IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
 940           Pentium 4, Xeon etc. The AMD support is for family 0x10 and
 941           0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
 942           You will obviously need the actual microcode binary data itself
 943           which is not shipped with the Linux kernel.
 944
 945           This option selects the general module only, you need to select
 946           at least one vendor specific module as well.
 947
 948           To compile this driver as a module, choose M here: the
 949           module will be called microcode.
 950
 951 config MICROCODE_INTEL
 952         bool "Intel microcode patch loading support"
 953         depends on MICROCODE
 954         default MICROCODE
 955         select FW_LOADER
 956         ---help---
 957           This options enables microcode patch loading support for Intel
 958           processors.
 959
 960           For latest news and information on obtaining all the required
 961           Intel ingredients for this driver, check:
 962           <http://www.urbanmyth.org/microcode/>.
 963
 964 config MICROCODE_AMD
 965         bool "AMD microcode patch loading support"
 966         depends on MICROCODE
 967         select FW_LOADER
 968         ---help---
 969           If you select this option, microcode patch loading support for AMD
 970           processors will be enabled.
 971
 972 config MICROCODE_OLD_INTERFACE
 973         def_bool y
 974         depends on MICROCODE
 975
 976 config X86_MSR
 977         tristate "/dev/cpu/*/msr - Model-specific register support"
 978         ---help---
 979           This device gives privileged processes access to the x86
 980           Model-Specific Registers (MSRs).  It is a character device with
 981           major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
 982           MSR accesses are directed to a specific CPU on multi-processor
 983           systems.
 984
 985 config X86_CPUID
 986         tristate "/dev/cpu/*/cpuid - CPU information support"
 987         ---help---
 988           This device gives processes access to the x86 CPUID instruction to
 989           be executed on a specific processor.  It is a character device
 990           with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
 991           /dev/cpu/31/cpuid.
 992
 993 config X86_CPU_DEBUG
 994         tristate "/sys/kernel/debug/x86/cpu/* - CPU Debug support"
 995         ---help---
 996           If you select this option, this will provide various x86 CPUs
 997           information through debugfs.
 998
 999 choice
1000         prompt "High Memory Support"
1001         default HIGHMEM4G if !X86_NUMAQ
1002         default HIGHMEM64G if X86_NUMAQ
1003         depends on X86_32
1004
1005 config NOHIGHMEM
1006         bool "off"
1007         depends on !X86_NUMAQ
1008         ---help---
1009           Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1010           However, the address space of 32-bit x86 processors is only 4
1011           Gigabytes large. That means that, if you have a large amount of
1012           physical memory, not all of it can be "permanently mapped" by the
1013           kernel. The physical memory that's not permanently mapped is called
1014           "high memory".
1015
1016           If you are compiling a kernel which will never run on a machine with
1017           more than 1 Gigabyte total physical RAM, answer "off" here (default
1018           choice and suitable for most users). This will result in a "3GB/1GB"
1019           split: 3GB are mapped so that each process sees a 3GB virtual memory
1020           space and the remaining part of the 4GB virtual memory space is used
1021           by the kernel to permanently map as much physical memory as
1022           possible.
1023
1024           If the machine has between 1 and 4 Gigabytes physical RAM, then
1025           answer "4GB" here.
1026
1027           If more than 4 Gigabytes is used then answer "64GB" here. This
1028           selection turns Intel PAE (Physical Address Extension) mode on.
1029           PAE implements 3-level paging on IA32 processors. PAE is fully
1030           supported by Linux, PAE mode is implemented on all recent Intel
1031           processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1032           then the kernel will not boot on CPUs that don't support PAE!
1033
1034           The actual amount of total physical memory will either be
1035           auto detected or can be forced by using a kernel command line option
1036           such as "mem=256M". (Try "man bootparam" or see the documentation of
1037           your boot loader (lilo or loadlin) about how to pass options to the
1038           kernel at boot time.)
1039
1040           If unsure, say "off".
1041
1042 config HIGHMEM4G
1043         bool "4GB"
1044         depends on !X86_NUMAQ
1045         ---help---
1046           Select this if you have a 32-bit processor and between 1 and 4
1047           gigabytes of physical RAM.
1048
1049 config HIGHMEM64G
1050         bool "64GB"
1051         depends on !M386 && !M486
1052         select X86_PAE
1053         ---help---
1054           Select this if you have a 32-bit processor and more than 4
1055           gigabytes of physical RAM.
1056
1057 endchoice
1058
1059 choice
1060         depends on EXPERIMENTAL
1061         prompt "Memory split" if EMBEDDED
1062         default VMSPLIT_3G
1063         depends on X86_32
1064         ---help---
1065           Select the desired split between kernel and user memory.
1066
1067           If the address range available to the kernel is less than the
1068           physical memory installed, the remaining memory will be available
1069           as "high memory". Accessing high memory is a little more costly
1070           than low memory, as it needs to be mapped into the kernel first.
1071           Note that increasing the kernel address space limits the range
1072           available to user programs, making the address space there
1073           tighter.  Selecting anything other than the default 3G/1G split
1074           will also likely make your kernel incompatible with binary-only
1075           kernel modules.
1076
1077           If you are not absolutely sure what you are doing, leave this
1078           option alone!
1079
1080         config VMSPLIT_3G
1081                 bool "3G/1G user/kernel split"
1082         config VMSPLIT_3G_OPT
1083                 depends on !X86_PAE
1084                 bool "3G/1G user/kernel split (for full 1G low memory)"
1085         config VMSPLIT_2G
1086                 bool "2G/2G user/kernel split"
1087         config VMSPLIT_2G_OPT
1088                 depends on !X86_PAE
1089                 bool "2G/2G user/kernel split (for full 2G low memory)"
1090         config VMSPLIT_1G
1091                 bool "1G/3G user/kernel split"
1092 endchoice
1093
1094 config PAGE_OFFSET
1095         hex
1096         default 0xB0000000 if VMSPLIT_3G_OPT
1097         default 0x80000000 if VMSPLIT_2G
1098         default 0x78000000 if VMSPLIT_2G_OPT
1099         default 0x40000000 if VMSPLIT_1G
1100         default 0xC0000000
1101         depends on X86_32
1102
1103 config HIGHMEM
1104         def_bool y
1105         depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1106
1107 config X86_PAE
1108         bool "PAE (Physical Address Extension) Support"
1109         depends on X86_32 && !HIGHMEM4G
1110         ---help---
1111           PAE is required for NX support, and furthermore enables
1112           larger swapspace support for non-overcommit purposes. It
1113           has the cost of more pagetable lookup overhead, and also
1114           consumes more pagetable space per process.
1115
1116 config ARCH_PHYS_ADDR_T_64BIT
1117         def_bool X86_64 || X86_PAE
1118
1119 config DIRECT_GBPAGES
1120         bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
1121         default y
1122         depends on X86_64
1123         ---help---
1124           Allow the kernel linear mapping to use 1GB pages on CPUs that
1125           support it. This can improve the kernel's performance a tiny bit by
1126           reducing TLB pressure. If in doubt, say "Y".
1127
1128 # Common NUMA Features
1129 config NUMA
1130         bool "Numa Memory Allocation and Scheduler Support"
1131         depends on SMP
1132         depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1133         default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1134         ---help---
1135           Enable NUMA (Non Uniform Memory Access) support.
1136
1137           The kernel will try to allocate memory used by a CPU on the
1138           local memory controller of the CPU and add some more
1139           NUMA awareness to the kernel.
1140
1141           For 64-bit this is recommended if the system is Intel Core i7
1142           (or later), AMD Opteron, or EM64T NUMA.
1143
1144           For 32-bit this is only needed on (rare) 32-bit-only platforms
1145           that support NUMA topologies, such as NUMAQ / Summit, or if you
1146           boot a 32-bit kernel on a 64-bit NUMA platform.
1147
1148           Otherwise, you should say N.
1149
1150 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1151         depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1152
1153 config K8_NUMA
1154         def_bool y
1155         prompt "Old style AMD Opteron NUMA detection"
1156         depends on X86_64 && NUMA && PCI
1157         ---help---
1158           Enable K8 NUMA node topology detection.  You should say Y here if
1159           you have a multi processor AMD K8 system. This uses an old
1160           method to read the NUMA configuration directly from the builtin
1161           Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
1162           instead, which also takes priority if both are compiled in.
1163
1164 config X86_64_ACPI_NUMA
1165         def_bool y
1166         prompt "ACPI NUMA detection"
1167         depends on X86_64 && NUMA && ACPI && PCI
1168         select ACPI_NUMA
1169         ---help---
1170           Enable ACPI SRAT based node topology detection.
1171
1172 # Some NUMA nodes have memory ranges that span
1173 # other nodes.  Even though a pfn is valid and
1174 # between a node's start and end pfns, it may not
1175 # reside on that node.  See memmap_init_zone()
1176 # for details.
1177 config NODES_SPAN_OTHER_NODES
1178         def_bool y
1179         depends on X86_64_ACPI_NUMA
1180
1181 config NUMA_EMU
1182         bool "NUMA emulation"
1183         depends on X86_64 && NUMA
1184         ---help---
1185           Enable NUMA emulation. A flat machine will be split
1186           into virtual nodes when booted with "numa=fake=N", where N is the
1187           number of nodes. This is only useful for debugging.
1188
1189 config NODES_SHIFT
1190         int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1191         range 1 9
1192         default "9" if MAXSMP
1193         default "6" if X86_64
1194         default "4" if X86_NUMAQ
1195         default "3"
1196         depends on NEED_MULTIPLE_NODES
1197         ---help---
1198           Specify the maximum number of NUMA Nodes available on the target
1199           system.  Increases memory reserved to accommodate various tables.
1200
1201 config HAVE_ARCH_BOOTMEM
1202         def_bool y
1203         depends on X86_32 && NUMA
1204
1205 config ARCH_HAVE_MEMORY_PRESENT
1206         def_bool y
1207         depends on X86_32 && DISCONTIGMEM
1208
1209 config NEED_NODE_MEMMAP_SIZE
1210         def_bool y
1211         depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1212
1213 config HAVE_ARCH_ALLOC_REMAP
1214         def_bool y
1215         depends on X86_32 && NUMA
1216
1217 config ARCH_FLATMEM_ENABLE
1218         def_bool y
1219         depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
1220
1221 config ARCH_DISCONTIGMEM_ENABLE
1222         def_bool y
1223         depends on NUMA && X86_32
1224
1225 config ARCH_DISCONTIGMEM_DEFAULT
1226         def_bool y
1227         depends on NUMA && X86_32
1228
1229 config ARCH_PROC_KCORE_TEXT
1230         def_bool y
1231         depends on X86_64 && PROC_KCORE
1232
1233 config ARCH_SPARSEMEM_DEFAULT
1234         def_bool y
1235         depends on X86_64
1236
1237 config ARCH_SPARSEMEM_ENABLE
1238         def_bool y
1239         depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1240         select SPARSEMEM_STATIC if X86_32
1241         select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1242
1243 config ARCH_SELECT_MEMORY_MODEL
1244         def_bool y
1245         depends on ARCH_SPARSEMEM_ENABLE
1246
1247 config ARCH_MEMORY_PROBE
1248         def_bool X86_64
1249         depends on MEMORY_HOTPLUG
1250
1251 config ILLEGAL_POINTER_VALUE
1252        hex
1253        default 0 if X86_32
1254        default 0xdead000000000000 if X86_64
1255
1256 source "mm/Kconfig"
1257
1258 config HIGHPTE
1259         bool "Allocate 3rd-level pagetables from highmem"
1260         depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1261         ---help---
1262           The VM uses one page table entry for each page of physical memory.
1263           For systems with a lot of RAM, this can be wasteful of precious
1264           low memory.  Setting this option will put user-space page table
1265           entries in high memory.
1266
1267 config X86_CHECK_BIOS_CORRUPTION
1268         bool "Check for low memory corruption"
1269         ---help---
1270           Periodically check for memory corruption in low memory, which
1271           is suspected to be caused by BIOS.  Even when enabled in the
1272           configuration, it is disabled at runtime.  Enable it by
1273           setting "memory_corruption_check=1" on the kernel command
1274           line.  By default it scans the low 64k of memory every 60
1275           seconds; see the memory_corruption_check_size and
1276           memory_corruption_check_period parameters in
1277           Documentation/kernel-parameters.txt to adjust this.
1278
1279           When enabled with the default parameters, this option has
1280           almost no overhead, as it reserves a relatively small amount
1281           of memory and scans it infrequently.  It both detects corruption
1282           and prevents it from affecting the running system.
1283
1284           It is, however, intended as a diagnostic tool; if repeatable
1285           BIOS-originated corruption always affects the same memory,
1286           you can use memmap= to prevent the kernel from using that
1287           memory.
1288
1289 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1290         bool "Set the default setting of memory_corruption_check"
1291         depends on X86_CHECK_BIOS_CORRUPTION
1292         default y
1293         ---help---
1294           Set whether the default state of memory_corruption_check is
1295           on or off.
1296
1297 config X86_RESERVE_LOW_64K
1298         bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
1299         default y
1300         ---help---
1301           Reserve the first 64K of physical RAM on BIOSes that are known
1302           to potentially corrupt that memory range. A numbers of BIOSes are
1303           known to utilize this area during suspend/resume, so it must not
1304           be used by the kernel.
1305
1306           Set this to N if you are absolutely sure that you trust the BIOS
1307           to get all its memory reservations and usages right.
1308
1309           If you have doubts about the BIOS (e.g. suspend/resume does not
1310           work or there's kernel crashes after certain hardware hotplug
1311           events) and it's not AMI or Phoenix, then you might want to enable
1312           X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
1313           corruption patterns.
1314
1315           Say Y if 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         bool
1345         default y
1346         prompt "MTRR (Memory Type Range Register) support" if EMBEDDED
1347         ---help---
1348           On Intel P6 family processors (Pentium Pro, Pentium II and later)
1349           the Memory Type Range Registers (MTRRs) may be used to control
1350           processor access to memory ranges. This is most useful if you have
1351           a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1352           allows bus write transfers to be combined into a larger transfer
1353           before bursting over the PCI/AGP bus. This can increase performance
1354           of image write operations 2.5 times or more. Saying Y here creates a
1355           /proc/mtrr file which may be used to manipulate your processor's
1356           MTRRs. Typically the X server should use this.
1357
1358           This code has a reasonably generic interface so that similar
1359           control registers on other processors can be easily supported
1360           as well:
1361
1362           The Cyrix 6x86, 6x86MX and M II processors have Address Range
1363           Registers (ARRs) which provide a similar functionality to MTRRs. For
1364           these, the ARRs are used to emulate the MTRRs.
1365           The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1366           MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1367           write-combining. All of these processors are supported by this code
1368           and it makes sense to say Y here if you have one of them.
1369
1370           Saying Y here also fixes a problem with buggy SMP BIOSes which only
1371           set the MTRRs for the boot CPU and not for the secondary CPUs. This
1372           can lead to all sorts of problems, so it's good to say Y here.
1373
1374           You can safely say Y even if your machine doesn't have MTRRs, you'll
1375           just add about 9 KB to your kernel.
1376
1377           See <file:Documentation/x86/mtrr.txt> for more information.
1378
1379 config MTRR_SANITIZER
1380         def_bool y
1381         prompt "MTRR cleanup support"
1382         depends on MTRR
1383         ---help---
1384           Convert MTRR layout from continuous to discrete, so X drivers can
1385           add writeback entries.
1386
1387           Can be disabled with disable_mtrr_cleanup on the kernel command line.
1388           The largest mtrr entry size for a continuous block can be set with
1389           mtrr_chunk_size.
1390
1391           If unsure, say Y.
1392
1393 config MTRR_SANITIZER_ENABLE_DEFAULT
1394         int "MTRR cleanup enable value (0-1)"
1395         range 0 1
1396         default "0"
1397         depends on MTRR_SANITIZER
1398         ---help---
1399           Enable mtrr cleanup default value
1400
1401 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1402         int "MTRR cleanup spare reg num (0-7)"
1403         range 0 7
1404         default "1"
1405         depends on MTRR_SANITIZER
1406         ---help---
1407           mtrr cleanup spare entries default, it can be changed via
1408           mtrr_spare_reg_nr=N on the kernel command line.
1409
1410 config X86_PAT
1411         bool
1412         default y
1413         prompt "x86 PAT support" if EMBEDDED
1414         depends on MTRR
1415         ---help---
1416           Use PAT attributes to setup page level cache control.
1417
1418           PATs are the modern equivalents of MTRRs and are much more
1419           flexible than MTRRs.
1420
1421           Say N here if you see bootup problems (boot crash, boot hang,
1422           spontaneous reboots) or a non-working video driver.
1423
1424           If unsure, say Y.
1425
1426 config ARCH_USES_PG_UNCACHED
1427         def_bool y
1428         depends on X86_PAT
1429
1430 config EFI
1431         bool "EFI runtime service support"
1432         depends on ACPI
1433         ---help---
1434           This enables the kernel to use EFI runtime services that are
1435           available (such as the EFI variable services).
1436
1437           This option is only useful on systems that have EFI firmware.
1438           In addition, you should use the latest ELILO loader available
1439           at <http://elilo.sourceforge.net> in order to take advantage
1440           of EFI runtime services. However, even with this option, the
1441           resultant kernel should continue to boot on existing non-EFI
1442           platforms.
1443
1444 config SECCOMP
1445         def_bool y
1446         prompt "Enable seccomp to safely compute untrusted bytecode"
1447         ---help---
1448           This kernel feature is useful for number crunching applications
1449           that may need to compute untrusted bytecode during their
1450           execution. By using pipes or other transports made available to
1451           the process as file descriptors supporting the read/write
1452           syscalls, it's possible to isolate those applications in
1453           their own address space using seccomp. Once seccomp is
1454           enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1455           and the task is only allowed to execute a few safe syscalls
1456           defined by each seccomp mode.
1457
1458           If unsure, say Y. Only embedded should say N here.
1459
1460 config CC_STACKPROTECTOR
1461         bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1462         ---help---
1463           This option turns on the -fstack-protector GCC feature. This
1464           feature puts, at the beginning of functions, a canary value on
1465           the stack just before the return address, and validates
1466           the value just before actually returning.  Stack based buffer
1467           overflows (that need to overwrite this return address) now also
1468           overwrite the canary, which gets detected and the attack is then
1469           neutralized via a kernel panic.
1470
1471           This feature requires gcc version 4.2 or above, or a distribution
1472           gcc with the feature backported. Older versions are automatically
1473           detected and for those versions, this configuration option is
1474           ignored. (and a warning is printed during bootup)
1475
1476 source kernel/Kconfig.hz
1477
1478 config KEXEC
1479         bool "kexec system call"
1480         ---help---
1481           kexec is a system call that implements the ability to shutdown your
1482           current kernel, and to start another kernel.  It is like a reboot
1483           but it is independent of the system firmware.   And like a reboot
1484           you can start any kernel with it, not just Linux.
1485
1486           The name comes from the similarity to the exec system call.
1487
1488           It is an ongoing process to be certain the hardware in a machine
1489           is properly shutdown, so do not be surprised if this code does not
1490           initially work for you.  It may help to enable device hotplugging
1491           support.  As of this writing the exact hardware interface is
1492           strongly in flux, so no good recommendation can be made.
1493
1494 config CRASH_DUMP
1495         bool "kernel crash dumps"
1496         depends on X86_64 || (X86_32 && HIGHMEM)
1497         ---help---
1498           Generate crash dump after being started by kexec.
1499           This should be normally only set in special crash dump kernels
1500           which are loaded in the main kernel with kexec-tools into
1501           a specially reserved region and then later executed after
1502           a crash by kdump/kexec. The crash dump kernel must be compiled
1503           to a memory address not used by the main kernel or BIOS using
1504           PHYSICAL_START, or it must be built as a relocatable image
1505           (CONFIG_RELOCATABLE=y).
1506           For more details see Documentation/kdump/kdump.txt
1507
1508 config KEXEC_JUMP
1509         bool "kexec jump (EXPERIMENTAL)"
1510         depends on EXPERIMENTAL
1511         depends on KEXEC && HIBERNATION
1512         ---help---
1513           Jump between original kernel and kexeced kernel and invoke
1514           code in physical address mode via KEXEC
1515
1516 config PHYSICAL_START
1517         hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1518         default "0x1000000"
1519         ---help---
1520           This gives the physical address where the kernel is loaded.
1521
1522           If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1523           bzImage will decompress itself to above physical address and
1524           run from there. Otherwise, bzImage will run from the address where
1525           it has been loaded by the boot loader and will ignore above physical
1526           address.
1527
1528           In normal kdump cases one does not have to set/change this option
1529           as now bzImage can be compiled as a completely relocatable image
1530           (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1531           address. This option is mainly useful for the folks who don't want
1532           to use a bzImage for capturing the crash dump and want to use a
1533           vmlinux instead. vmlinux is not relocatable hence a kernel needs
1534           to be specifically compiled to run from a specific memory area
1535           (normally a reserved region) and this option comes handy.
1536
1537           So if you are using bzImage for capturing the crash dump,
1538           leave the value here unchanged to 0x1000000 and set
1539           CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
1540           for capturing the crash dump change this value to start of
1541           the reserved region.  In other words, it can be set based on
1542           the "X" value as specified in the "crashkernel=YM@XM"
1543           command line boot parameter passed to the panic-ed
1544           kernel. Please take a look at Documentation/kdump/kdump.txt
1545           for more details about crash dumps.
1546
1547           Usage of bzImage for capturing the crash dump is recommended as
1548           one does not have to build two kernels. Same kernel can be used
1549           as production kernel and capture kernel. Above option should have
1550           gone away after relocatable bzImage support is introduced. But it
1551           is present because there are users out there who continue to use
1552           vmlinux for dump capture. This option should go away down the
1553           line.
1554
1555           Don't change this unless you know what you are doing.
1556
1557 config RELOCATABLE
1558         bool "Build a relocatable kernel"
1559         default y
1560         ---help---
1561           This builds a kernel image that retains relocation information
1562           so it can be loaded someplace besides the default 1MB.
1563           The relocations tend to make the kernel binary about 10% larger,
1564           but are discarded at runtime.
1565
1566           One use is for the kexec on panic case where the recovery kernel
1567           must live at a different physical address than the primary
1568           kernel.
1569
1570           Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1571           it has been loaded at and the compile time physical address
1572           (CONFIG_PHYSICAL_START) is ignored.
1573
1574 # Relocation on x86-32 needs some additional build support
1575 config X86_NEED_RELOCS
1576         def_bool y
1577         depends on X86_32 && RELOCATABLE
1578
1579 config PHYSICAL_ALIGN
1580         hex
1581         prompt "Alignment value to which kernel should be aligned" if X86_32
1582         default "0x1000000"
1583         range 0x2000 0x1000000
1584         ---help---
1585           This value puts the alignment restrictions on physical address
1586           where kernel is loaded and run from. Kernel is compiled for an
1587           address which meets above alignment restriction.
1588
1589           If bootloader loads the kernel at a non-aligned address and
1590           CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1591           address aligned to above value and run from there.
1592
1593           If bootloader loads the kernel at a non-aligned address and
1594           CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1595           load address and decompress itself to the address it has been
1596           compiled for and run from there. The address for which kernel is
1597           compiled already meets above alignment restrictions. Hence the
1598           end result is that kernel runs from a physical address meeting
1599           above alignment restrictions.
1600
1601           Don't change this unless you know what you are doing.
1602
1603 config HOTPLUG_CPU
1604         bool "Support for hot-pluggable CPUs"
1605         depends on SMP && HOTPLUG
1606         ---help---
1607           Say Y here to allow turning CPUs off and on. CPUs can be
1608           controlled through /sys/devices/system/cpu.
1609           ( Note: power management support will enable this option
1610             automatically on SMP systems. )
1611           Say N if you want to disable CPU hotplug.
1612
1613 config COMPAT_VDSO
1614         def_bool y
1615         prompt "Compat VDSO support"
1616         depends on X86_32 || IA32_EMULATION
1617         ---help---
1618           Map the 32-bit VDSO to the predictable old-style address too.
1619
1620           Say N here if you are running a sufficiently recent glibc
1621           version (2.3.3 or later), to remove the high-mapped
1622           VDSO mapping and to exclusively use the randomized VDSO.
1623
1624           If unsure, say Y.
1625
1626 config CMDLINE_BOOL
1627         bool "Built-in kernel command line"
1628         default n
1629         ---help---
1630           Allow for specifying boot arguments to the kernel at
1631           build time.  On some systems (e.g. embedded ones), it is
1632           necessary or convenient to provide some or all of the
1633           kernel boot arguments with the kernel itself (that is,
1634           to not rely on the boot loader to provide them.)
1635
1636           To compile command line arguments into the kernel,
1637           set this option to 'Y', then fill in the
1638           the boot arguments in CONFIG_CMDLINE.
1639
1640           Systems with fully functional boot loaders (i.e. non-embedded)
1641           should leave this option set to 'N'.
1642
1643 config CMDLINE
1644         string "Built-in kernel command string"
1645         depends on CMDLINE_BOOL
1646         default ""
1647         ---help---
1648           Enter arguments here that should be compiled into the kernel
1649           image and used at boot time.  If the boot loader provides a
1650           command line at boot time, it is appended to this string to
1651           form the full kernel command line, when the system boots.
1652
1653           However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1654           change this behavior.
1655
1656           In most cases, the command line (whether built-in or provided
1657           by the boot loader) should specify the device for the root
1658           file system.
1659
1660 config CMDLINE_OVERRIDE
1661         bool "Built-in command line overrides boot loader arguments"
1662         default n
1663         depends on CMDLINE_BOOL
1664         ---help---
1665           Set this option to 'Y' to have the kernel ignore the boot loader
1666           command line, and use ONLY the built-in command line.
1667
1668           This is used to work around broken boot loaders.  This should
1669           be set to 'N' under normal conditions.
1670
1671 endmenu
1672
1673 config ARCH_ENABLE_MEMORY_HOTPLUG
1674         def_bool y
1675         depends on X86_64 || (X86_32 && HIGHMEM)
1676
1677 config ARCH_ENABLE_MEMORY_HOTREMOVE
1678         def_bool y
1679         depends on MEMORY_HOTPLUG
1680
1681 config HAVE_ARCH_EARLY_PFN_TO_NID
1682         def_bool X86_64
1683         depends on NUMA
1684
1685 menu "Power management and ACPI options"
1686
1687 config ARCH_HIBERNATION_HEADER
1688         def_bool y
1689         depends on X86_64 && HIBERNATION
1690
1691 source "kernel/power/Kconfig"
1692
1693 source "drivers/acpi/Kconfig"
1694
1695 source "drivers/sfi/Kconfig"
1696
1697 config X86_APM_BOOT
1698         bool
1699         default y
1700         depends on APM || APM_MODULE
1701
1702 menuconfig APM
1703         tristate "APM (Advanced Power Management) BIOS support"
1704         depends on X86_32 && PM_SLEEP
1705         ---help---
1706           APM is a BIOS specification for saving power using several different
1707           techniques. This is mostly useful for battery powered laptops with
1708           APM compliant BIOSes. If you say Y here, the system time will be
1709           reset after a RESUME operation, the /proc/apm device will provide
1710           battery status information, and user-space programs will receive
1711           notification of APM "events" (e.g. battery status change).
1712
1713           If you select "Y" here, you can disable actual use of the APM
1714           BIOS by passing the "apm=off" option to the kernel at boot time.
1715
1716           Note that the APM support is almost completely disabled for
1717           machines with more than one CPU.
1718
1719           In order to use APM, you will need supporting software. For location
1720           and more information, read <file:Documentation/power/pm.txt> and the
1721           Battery Powered Linux mini-HOWTO, available from
1722           <http://www.tldp.org/docs.html#howto>.
1723
1724           This driver does not spin down disk drives (see the hdparm(8)
1725           manpage ("man 8 hdparm") for that), and it doesn't turn off
1726           VESA-compliant "green" monitors.
1727
1728           This driver does not support the TI 4000M TravelMate and the ACER
1729           486/DX4/75 because they don't have compliant BIOSes. Many "green"
1730           desktop machines also don't have compliant BIOSes, and this driver
1731           may cause those machines to panic during the boot phase.
1732
1733           Generally, if you don't have a battery in your machine, there isn't
1734           much point in using this driver and you should say N. If you get
1735           random kernel OOPSes or reboots that don't seem to be related to
1736           anything, try disabling/enabling this option (or disabling/enabling
1737           APM in your BIOS).
1738
1739           Some other things you should try when experiencing seemingly random,
1740           "weird" problems:
1741
1742           1) make sure that you have enough swap space and that it is
1743           enabled.
1744           2) pass the "no-hlt" option to the kernel
1745           3) switch on floating point emulation in the kernel and pass
1746           the "no387" option to the kernel
1747           4) pass the "floppy=nodma" option to the kernel
1748           5) pass the "mem=4M" option to the kernel (thereby disabling
1749           all but the first 4 MB of RAM)
1750           6) make sure that the CPU is not over clocked.
1751           7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1752           8) disable the cache from your BIOS settings
1753           9) install a fan for the video card or exchange video RAM
1754           10) install a better fan for the CPU
1755           11) exchange RAM chips
1756           12) exchange the motherboard.
1757
1758           To compile this driver as a module, choose M here: the
1759           module will be called apm.
1760
1761 if APM
1762
1763 config APM_IGNORE_USER_SUSPEND
1764         bool "Ignore USER SUSPEND"
1765         ---help---
1766           This option will ignore USER SUSPEND requests. On machines with a
1767           compliant APM BIOS, you want to say N. However, on the NEC Versa M
1768           series notebooks, it is necessary to say Y because of a BIOS bug.
1769
1770 config APM_DO_ENABLE
1771         bool "Enable PM at boot time"
1772         ---help---
1773           Enable APM features at boot time. From page 36 of the APM BIOS
1774           specification: "When disabled, the APM BIOS does not automatically
1775           power manage devices, enter the Standby State, enter the Suspend
1776           State, or take power saving steps in response to CPU Idle calls."
1777           This driver will make CPU Idle calls when Linux is idle (unless this
1778           feature is turned off -- see "Do CPU IDLE calls", below). This
1779           should always save battery power, but more complicated APM features
1780           will be dependent on your BIOS implementation. You may need to turn
1781           this option off if your computer hangs at boot time when using APM
1782           support, or if it beeps continuously instead of suspending. Turn
1783           this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1784           T400CDT. This is off by default since most machines do fine without
1785           this feature.
1786
1787 config APM_CPU_IDLE
1788         bool "Make CPU Idle calls when idle"
1789         ---help---
1790           Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1791           On some machines, this can activate improved power savings, such as
1792           a slowed CPU clock rate, when the machine is idle. These idle calls
1793           are made after the idle loop has run for some length of time (e.g.,
1794           333 mS). On some machines, this will cause a hang at boot time or
1795           whenever the CPU becomes idle. (On machines with more than one CPU,
1796           this option does nothing.)
1797
1798 config APM_DISPLAY_BLANK
1799         bool "Enable console blanking using APM"
1800         ---help---
1801           Enable console blanking using the APM. Some laptops can use this to
1802           turn off the LCD backlight when the screen blanker of the Linux
1803           virtual console blanks the screen. Note that this is only used by
1804           the virtual console screen blanker, and won't turn off the backlight
1805           when using the X Window system. This also doesn't have anything to
1806           do with your VESA-compliant power-saving monitor. Further, this
1807           option doesn't work for all laptops -- it might not turn off your
1808           backlight at all, or it might print a lot of errors to the console,
1809           especially if you are using gpm.
1810
1811 config APM_ALLOW_INTS
1812         bool "Allow interrupts during APM BIOS calls"
1813         ---help---
1814           Normally we disable external interrupts while we are making calls to
1815           the APM BIOS as a measure to lessen the effects of a badly behaving
1816           BIOS implementation.  The BIOS should reenable interrupts if it
1817           needs to.  Unfortunately, some BIOSes do not -- especially those in
1818           many of the newer IBM Thinkpads.  If you experience hangs when you
1819           suspend, try setting this to Y.  Otherwise, say N.
1820
1821 endif # APM
1822
1823 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1824
1825 source "drivers/cpuidle/Kconfig"
1826
1827 source "drivers/idle/Kconfig"
1828
1829 endmenu
1830
1831
1832 menu "Bus options (PCI etc.)"
1833
1834 config PCI
1835         bool "PCI support"
1836         default y
1837         select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1838         ---help---
1839           Find out whether you have a PCI motherboard. PCI is the name of a
1840           bus system, i.e. the way the CPU talks to the other stuff inside
1841           your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1842           VESA. If you have PCI, say Y, otherwise N.
1843
1844 choice
1845         prompt "PCI access mode"
1846         depends on X86_32 && PCI
1847         default PCI_GOANY
1848         ---help---
1849           On PCI systems, the BIOS can be used to detect the PCI devices and
1850           determine their configuration. However, some old PCI motherboards
1851           have BIOS bugs and may crash if this is done. Also, some embedded
1852           PCI-based systems don't have any BIOS at all. Linux can also try to
1853           detect the PCI hardware directly without using the BIOS.
1854
1855           With this option, you can specify how Linux should detect the
1856           PCI devices. If you choose "BIOS", the BIOS will be used,
1857           if you choose "Direct", the BIOS won't be used, and if you
1858           choose "MMConfig", then PCI Express MMCONFIG will be used.
1859           If you choose "Any", the kernel will try MMCONFIG, then the
1860           direct access method and falls back to the BIOS if that doesn't
1861           work. If unsure, go with the default, which is "Any".
1862
1863 config PCI_GOBIOS
1864         bool "BIOS"
1865
1866 config PCI_GOMMCONFIG
1867         bool "MMConfig"
1868
1869 config PCI_GODIRECT
1870         bool "Direct"
1871
1872 config PCI_GOOLPC
1873         bool "OLPC"
1874         depends on OLPC
1875
1876 config PCI_GOANY
1877         bool "Any"
1878
1879 endchoice
1880
1881 config PCI_BIOS
1882         def_bool y
1883         depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1884
1885 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1886 config PCI_DIRECT
1887         def_bool y
1888         depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1889
1890 config PCI_MMCONFIG
1891         def_bool y
1892         depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
1893
1894 config PCI_OLPC
1895         def_bool y
1896         depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1897
1898 config PCI_DOMAINS
1899         def_bool y
1900         depends on PCI
1901
1902 config PCI_MMCONFIG
1903         bool "Support mmconfig PCI config space access"
1904         depends on X86_64 && PCI && ACPI
1905
1906 config DMAR
1907         bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1908         depends on PCI_MSI && ACPI && EXPERIMENTAL
1909         help
1910           DMA remapping (DMAR) devices support enables independent address
1911           translations for Direct Memory Access (DMA) from devices.
1912           These DMA remapping devices are reported via ACPI tables
1913           and include PCI device scope covered by these DMA
1914           remapping devices.
1915
1916 config DMAR_DEFAULT_ON
1917         def_bool y
1918         prompt "Enable DMA Remapping Devices by default"
1919         depends on DMAR
1920         help
1921           Selecting this option will enable a DMAR device at boot time if
1922           one is found. If this option is not selected, DMAR support can
1923           be enabled by passing intel_iommu=on to the kernel. It is
1924           recommended you say N here while the DMAR code remains
1925           experimental.
1926
1927 config DMAR_BROKEN_GFX_WA
1928         def_bool n
1929         prompt "Workaround broken graphics drivers (going away soon)"
1930         depends on DMAR && BROKEN
1931         ---help---
1932           Current Graphics drivers tend to use physical address
1933           for DMA and avoid using DMA APIs. Setting this config
1934           option permits the IOMMU driver to set a unity map for
1935           all the OS-visible memory. Hence the driver can continue
1936           to use physical addresses for DMA, at least until this
1937           option is removed in the 2.6.32 kernel.
1938
1939 config DMAR_FLOPPY_WA
1940         def_bool y
1941         depends on DMAR
1942         ---help---
1943           Floppy disk drivers are known to bypass DMA API calls
1944           thereby failing to work when IOMMU is enabled. This
1945           workaround will setup a 1:1 mapping for the first
1946           16MiB to make floppy (an ISA device) work.
1947
1948 config INTR_REMAP
1949         bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1950         depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
1951         ---help---
1952           Supports Interrupt remapping for IO-APIC and MSI devices.
1953           To use x2apic mode in the CPU's which support x2APIC enhancements or
1954           to support platforms with CPU's having > 8 bit APIC ID, say Y.
1955
1956 source "drivers/pci/pcie/Kconfig"
1957
1958 source "drivers/pci/Kconfig"
1959
1960 # x86_64 have no ISA slots, but do have ISA-style DMA.
1961 config ISA_DMA_API
1962         def_bool y
1963
1964 if X86_32
1965
1966 config ISA
1967         bool "ISA support"
1968         ---help---
1969           Find out whether you have ISA slots on your motherboard.  ISA is the
1970           name of a bus system, i.e. the way the CPU talks to the other stuff
1971           inside your box.  Other bus systems are PCI, EISA, MicroChannel
1972           (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
1973           newer boards don't support it.  If you have ISA, say Y, otherwise N.
1974
1975 config EISA
1976         bool "EISA support"
1977         depends on ISA
1978         ---help---
1979           The Extended Industry Standard Architecture (EISA) bus was
1980           developed as an open alternative to the IBM MicroChannel bus.
1981
1982           The EISA bus provided some of the features of the IBM MicroChannel
1983           bus while maintaining backward compatibility with cards made for
1984           the older ISA bus.  The EISA bus saw limited use between 1988 and
1985           1995 when it was made obsolete by the PCI bus.
1986
1987           Say Y here if you are building a kernel for an EISA-based machine.
1988
1989           Otherwise, say N.
1990
1991 source "drivers/eisa/Kconfig"
1992
1993 config MCA
1994         bool "MCA support"
1995         ---help---
1996           MicroChannel Architecture is found in some IBM PS/2 machines and
1997           laptops.  It is a bus system similar to PCI or ISA. See
1998           <file:Documentation/mca.txt> (and especially the web page given
1999           there) before attempting to build an MCA bus kernel.
2000
2001 source "drivers/mca/Kconfig"
2002
2003 config SCx200
2004         tristate "NatSemi SCx200 support"
2005         ---help---
2006           This provides basic support for National Semiconductor's
2007           (now AMD's) Geode processors.  The driver probes for the
2008           PCI-IDs of several on-chip devices, so its a good dependency
2009           for other scx200_* drivers.
2010
2011           If compiled as a module, the driver is named scx200.
2012
2013 config SCx200HR_TIMER
2014         tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2015         depends on SCx200 && GENERIC_TIME
2016         default y
2017         ---help---
2018           This driver provides a clocksource built upon the on-chip
2019           27MHz high-resolution timer.  Its also a workaround for
2020           NSC Geode SC-1100's buggy TSC, which loses time when the
2021           processor goes idle (as is done by the scheduler).  The
2022           other workaround is idle=poll boot option.
2023
2024 config OLPC
2025         bool "One Laptop Per Child support"
2026         select GPIOLIB
2027         default n
2028         ---help---
2029           Add support for detecting the unique features of the OLPC
2030           XO hardware.
2031
2032 endif # X86_32
2033
2034 config K8_NB
2035         def_bool y
2036         depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
2037
2038 source "drivers/pcmcia/Kconfig"
2039
2040 source "drivers/pci/hotplug/Kconfig"
2041
2042 endmenu
2043
2044
2045 menu "Executable file formats / Emulations"
2046
2047 source "fs/Kconfig.binfmt"
2048
2049 config IA32_EMULATION
2050         bool "IA32 Emulation"
2051         depends on X86_64
2052         select COMPAT_BINFMT_ELF
2053         ---help---
2054           Include code to run 32-bit programs under a 64-bit kernel. You should
2055           likely turn this on, unless you're 100% sure that you don't have any
2056           32-bit programs left.
2057
2058 config IA32_AOUT
2059         tristate "IA32 a.out support"
2060         depends on IA32_EMULATION
2061         ---help---
2062           Support old a.out binaries in the 32bit emulation.
2063
2064 config COMPAT
2065         def_bool y
2066         depends on IA32_EMULATION
2067
2068 config COMPAT_FOR_U64_ALIGNMENT
2069         def_bool COMPAT
2070         depends on X86_64
2071
2072 config SYSVIPC_COMPAT
2073         def_bool y
2074         depends on COMPAT && SYSVIPC
2075
2076 endmenu
2077
2078
2079 config HAVE_ATOMIC_IOMAP
2080         def_bool y
2081         depends on X86_32
2082
2083 source "net/Kconfig"
2084
2085 source "drivers/Kconfig"
2086
2087 source "drivers/firmware/Kconfig"
2088
2089 source "fs/Kconfig"
2090
2091 source "arch/x86/Kconfig.debug"
2092
2093 source "security/Kconfig"
2094
2095 source "crypto/Kconfig"
2096
2097 source "arch/x86/kvm/Kconfig"
2098
2099 source "lib/Kconfig"