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_IOREMAP_PROT
  28         select HAVE_KPROBES
  29         select ARCH_WANT_OPTIONAL_GPIOLIB
  30         select ARCH_WANT_FRAME_POINTERS
  31         select HAVE_KRETPROBES
  32         select HAVE_FTRACE_MCOUNT_RECORD
  33         select HAVE_DYNAMIC_FTRACE
  34         select HAVE_FUNCTION_TRACER
  35         select HAVE_FUNCTION_GRAPH_TRACER
  36         select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  37         select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
  38         select HAVE_FTRACE_SYSCALLS
  39         select HAVE_KVM
  40         select HAVE_ARCH_KGDB
  41         select HAVE_ARCH_TRACEHOOK
  42         select HAVE_GENERIC_DMA_COHERENT if X86_32
  43         select HAVE_EFFICIENT_UNALIGNED_ACCESS
  44         select USER_STACKTRACE_SUPPORT
  45         select HAVE_DMA_API_DEBUG
  46         select HAVE_KERNEL_GZIP
  47         select HAVE_KERNEL_BZIP2
  48         select HAVE_KERNEL_LZMA
  49
  50 config OUTPUT_FORMAT
  51         string
  52         default "elf32-i386" if X86_32
  53         default "elf64-x86-64" if X86_64
  54
  55 config ARCH_DEFCONFIG
  56         string
  57         default "arch/x86/configs/i386_defconfig" if X86_32
  58         default "arch/x86/configs/x86_64_defconfig" if X86_64
  59
  60 config GENERIC_TIME
  61         def_bool y
  62
  63 config GENERIC_CMOS_UPDATE
  64         def_bool y
  65
  66 config CLOCKSOURCE_WATCHDOG
  67         def_bool y
  68
  69 config GENERIC_CLOCKEVENTS
  70         def_bool y
  71
  72 config GENERIC_CLOCKEVENTS_BROADCAST
  73         def_bool y
  74         depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  75
  76 config LOCKDEP_SUPPORT
  77         def_bool y
  78
  79 config STACKTRACE_SUPPORT
  80         def_bool y
  81
  82 config HAVE_LATENCYTOP_SUPPORT
  83         def_bool y
  84
  85 config FAST_CMPXCHG_LOCAL
  86         bool
  87         default y
  88
  89 config MMU
  90         def_bool y
  91
  92 config ZONE_DMA
  93         def_bool y
  94
  95 config SBUS
  96         bool
  97
  98 config GENERIC_ISA_DMA
  99         def_bool y
 100
 101 config GENERIC_IOMAP
 102         def_bool y
 103
 104 config GENERIC_BUG
 105         def_bool y
 106         depends on BUG
 107         select GENERIC_BUG_RELATIVE_POINTERS if X86_64
 108
 109 config GENERIC_BUG_RELATIVE_POINTERS
 110         bool
 111
 112 config GENERIC_HWEIGHT
 113         def_bool y
 114
 115 config GENERIC_GPIO
 116         bool
 117
 118 config ARCH_MAY_HAVE_PC_FDC
 119         def_bool y
 120
 121 config RWSEM_GENERIC_SPINLOCK
 122         def_bool !X86_XADD
 123
 124 config RWSEM_XCHGADD_ALGORITHM
 125         def_bool X86_XADD
 126
 127 config ARCH_HAS_CPU_IDLE_WAIT
 128         def_bool y
 129
 130 config GENERIC_CALIBRATE_DELAY
 131         def_bool y
 132
 133 config GENERIC_TIME_VSYSCALL
 134         bool
 135         default X86_64
 136
 137 config ARCH_HAS_CPU_RELAX
 138         def_bool y
 139
 140 config ARCH_HAS_DEFAULT_IDLE
 141         def_bool y
 142
 143 config ARCH_HAS_CACHE_LINE_SIZE
 144         def_bool y
 145
 146 config HAVE_SETUP_PER_CPU_AREA
 147         def_bool y
 148
 149 config HAVE_DYNAMIC_PER_CPU_AREA
 150         def_bool y
 151
 152 config HAVE_CPUMASK_OF_CPU_MAP
 153         def_bool X86_64_SMP
 154
 155 config ARCH_HIBERNATION_POSSIBLE
 156         def_bool y
 157
 158 config ARCH_SUSPEND_POSSIBLE
 159         def_bool y
 160
 161 config ZONE_DMA32
 162         bool
 163         default X86_64
 164
 165 config ARCH_POPULATES_NODE_MAP
 166         def_bool y
 167
 168 config AUDIT_ARCH
 169         bool
 170         default X86_64
 171
 172 config ARCH_SUPPORTS_OPTIMIZED_INLINING
 173         def_bool y
 174
 175 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
 176         def_bool y
 177
 178 # Use the generic interrupt handling code in kernel/irq/:
 179 config GENERIC_HARDIRQS
 180         bool
 181         default y
 182
 183 config GENERIC_HARDIRQS_NO__DO_IRQ
 184        def_bool y
 185
 186 config GENERIC_IRQ_PROBE
 187         bool
 188         default y
 189
 190 config GENERIC_PENDING_IRQ
 191         bool
 192         depends on GENERIC_HARDIRQS && SMP
 193         default y
 194
 195 config USE_GENERIC_SMP_HELPERS
 196         def_bool y
 197         depends on SMP
 198
 199 config X86_32_SMP
 200         def_bool y
 201         depends on X86_32 && SMP
 202
 203 config X86_64_SMP
 204         def_bool y
 205         depends on X86_64 && SMP
 206
 207 config X86_HT
 208         bool
 209         depends on SMP
 210         default y
 211
 212 config X86_TRAMPOLINE
 213         bool
 214         depends on SMP || (64BIT && ACPI_SLEEP)
 215         default y
 216
 217 config X86_32_LAZY_GS
 218         def_bool y
 219         depends on X86_32 && !CC_STACKPROTECTOR
 220
 221 config KTIME_SCALAR
 222         def_bool X86_32
 223 source "init/Kconfig"
 224 source "kernel/Kconfig.freezer"
 225
 226 menu "Processor type and features"
 227
 228 source "kernel/time/Kconfig"
 229
 230 config SMP
 231         bool "Symmetric multi-processing support"
 232         ---help---
 233           This enables support for systems with more than one CPU. If you have
 234           a system with only one CPU, like most personal computers, say N. If
 235           you have a system with more than one CPU, say Y.
 236
 237           If you say N here, the kernel will run on single and multiprocessor
 238           machines, but will use only one CPU of a multiprocessor machine. If
 239           you say Y here, the kernel will run on many, but not all,
 240           singleprocessor machines. On a singleprocessor machine, the kernel
 241           will run faster if you say N here.
 242
 243           Note that if you say Y here and choose architecture "586" or
 244           "Pentium" under "Processor family", the kernel will not work on 486
 245           architectures. Similarly, multiprocessor kernels for the "PPro"
 246           architecture may not work on all Pentium based boards.
 247
 248           People using multiprocessor machines who say Y here should also say
 249           Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
 250           Management" code will be disabled if you say Y here.
 251
 252           See also <file:Documentation/i386/IO-APIC.txt>,
 253           <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
 254           <http://www.tldp.org/docs.html#howto>.
 255
 256           If you don't know what to do here, say N.
 257
 258 config X86_X2APIC
 259         bool "Support x2apic"
 260         depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
 261         ---help---
 262           This enables x2apic support on CPUs that have this feature.
 263
 264           This allows 32-bit apic IDs (so it can support very large systems),
 265           and accesses the local apic via MSRs not via mmio.
 266
 267           If you don't know what to do here, say N.
 268
 269 config SPARSE_IRQ
 270         bool "Support sparse irq numbering"
 271         depends on PCI_MSI || HT_IRQ
 272         ---help---
 273           This enables support for sparse irqs. This is useful for distro
 274           kernels that want to define a high CONFIG_NR_CPUS value but still
 275           want to have low kernel memory footprint on smaller machines.
 276
 277           ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
 278             out the irq_desc[] array in a more NUMA-friendly way. )
 279
 280           If you don't know what to do here, say N.
 281
 282 config NUMA_IRQ_DESC
 283         def_bool y
 284         depends on SPARSE_IRQ && NUMA
 285
 286 config X86_MPPARSE
 287         bool "Enable MPS table" if ACPI
 288         default y
 289         depends on X86_LOCAL_APIC
 290         ---help---
 291           For old smp systems that do not have proper acpi support. Newer systems
 292           (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
 293
 294 config X86_BIGSMP
 295         bool "Support for big SMP systems with more than 8 CPUs"
 296         depends on X86_32 && SMP
 297         ---help---
 298           This option is needed for the systems that have more than 8 CPUs
 299
 300 if X86_32
 301 config X86_EXTENDED_PLATFORM
 302         bool "Support for extended (non-PC) x86 platforms"
 303         default y
 304         ---help---
 305           If you disable this option then the kernel will only support
 306           standard PC platforms. (which covers the vast majority of
 307           systems out there.)
 308
 309           If you enable this option then you'll be able to select support
 310           for the following (non-PC) 32 bit x86 platforms:
 311                 AMD Elan
 312                 NUMAQ (IBM/Sequent)
 313                 RDC R-321x SoC
 314                 SGI 320/540 (Visual Workstation)
 315                 Summit/EXA (IBM x440)
 316                 Unisys ES7000 IA32 series
 317
 318           If you have one of these systems, or if you want to build a
 319           generic distribution kernel, say Y here - otherwise say N.
 320 endif
 321
 322 if X86_64
 323 config X86_EXTENDED_PLATFORM
 324         bool "Support for extended (non-PC) x86 platforms"
 325         default y
 326         ---help---
 327           If you disable this option then the kernel will only support
 328           standard PC platforms. (which covers the vast majority of
 329           systems out there.)
 330
 331           If you enable this option then you'll be able to select support
 332           for the following (non-PC) 64 bit x86 platforms:
 333                 ScaleMP vSMP
 334                 SGI Ultraviolet
 335
 336           If you have one of these systems, or if you want to build a
 337           generic distribution kernel, say Y here - otherwise say N.
 338 endif
 339 # This is an alphabetically sorted list of 64 bit extended platforms
 340 # Please maintain the alphabetic order if and when there are additions
 341
 342 config X86_VSMP
 343         bool "ScaleMP vSMP"
 344         select PARAVIRT
 345         depends on X86_64 && PCI
 346         depends on X86_EXTENDED_PLATFORM
 347         ---help---
 348           Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
 349           supposed to run on these EM64T-based machines.  Only choose this option
 350           if you have one of these machines.
 351
 352 config X86_UV
 353         bool "SGI Ultraviolet"
 354         depends on X86_64
 355         depends on X86_EXTENDED_PLATFORM
 356         depends on NUMA
 357         depends on X86_X2APIC
 358         ---help---
 359           This option is needed in order to support SGI Ultraviolet systems.
 360           If you don't have one of these, you should say N here.
 361
 362 # Following is an alphabetically sorted list of 32 bit extended platforms
 363 # Please maintain the alphabetic order if and when there are additions
 364
 365 config X86_ELAN
 366         bool "AMD Elan"
 367         depends on X86_32
 368         depends on X86_EXTENDED_PLATFORM
 369         ---help---
 370           Select this for an AMD Elan processor.
 371
 372           Do not use this option for K6/Athlon/Opteron processors!
 373
 374           If unsure, choose "PC-compatible" instead.
 375
 376 config X86_RDC321X
 377         bool "RDC R-321x SoC"
 378         depends on X86_32
 379         depends on X86_EXTENDED_PLATFORM
 380         select M486
 381         select X86_REBOOTFIXUPS
 382         ---help---
 383           This option is needed for RDC R-321x system-on-chip, also known
 384           as R-8610-(G).
 385           If you don't have one of these chips, you should say N here.
 386
 387 config X86_32_NON_STANDARD
 388         bool "Support non-standard 32-bit SMP architectures"
 389         depends on X86_32 && SMP
 390         depends on X86_EXTENDED_PLATFORM
 391         ---help---
 392           This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
 393           subarchitectures.  It is intended for a generic binary kernel.
 394           if you select them all, kernel will probe it one by one. and will
 395           fallback to default.
 396
 397 # Alphabetically sorted list of Non standard 32 bit platforms
 398
 399 config X86_NUMAQ
 400         bool "NUMAQ (IBM/Sequent)"
 401         depends on X86_32_NON_STANDARD
 402         select NUMA
 403         select X86_MPPARSE
 404         ---help---
 405           This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
 406           NUMA multiquad box. This changes the way that processors are
 407           bootstrapped, and uses Clustered Logical APIC addressing mode instead
 408           of Flat Logical.  You will need a new lynxer.elf file to flash your
 409           firmware with - send email to <Martin.Bligh@us.ibm.com>.
 410
 411 config X86_VISWS
 412         bool "SGI 320/540 (Visual Workstation)"
 413         depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
 414         depends on X86_32_NON_STANDARD
 415         ---help---
 416           The SGI Visual Workstation series is an IA32-based workstation
 417           based on SGI systems chips with some legacy PC hardware attached.
 418
 419           Say Y here to create a kernel to run on the SGI 320 or 540.
 420
 421           A kernel compiled for the Visual Workstation will run on general
 422           PCs as well. See <file:Documentation/sgi-visws.txt> for details.
 423
 424 config X86_SUMMIT
 425         bool "Summit/EXA (IBM x440)"
 426         depends on X86_32_NON_STANDARD
 427         ---help---
 428           This option is needed for IBM systems that use the Summit/EXA chipset.
 429           In particular, it is needed for the x440.
 430
 431 config X86_ES7000
 432         bool "Unisys ES7000 IA32 series"
 433         depends on X86_32_NON_STANDARD && X86_BIGSMP
 434         ---help---
 435           Support for Unisys ES7000 systems.  Say 'Y' here if this kernel is
 436           supposed to run on an IA32-based Unisys ES7000 system.
 437
 438 config SCHED_OMIT_FRAME_POINTER
 439         def_bool y
 440         prompt "Single-depth WCHAN output"
 441         depends on X86
 442         ---help---
 443           Calculate simpler /proc/<PID>/wchan values. If this option
 444           is disabled then wchan values will recurse back to the
 445           caller function. This provides more accurate wchan values,
 446           at the expense of slightly more scheduling overhead.
 447
 448           If in doubt, say "Y".
 449
 450 menuconfig PARAVIRT_GUEST
 451         bool "Paravirtualized guest support"
 452         ---help---
 453           Say Y here to get to see options related to running Linux under
 454           various hypervisors.  This option alone does not add any kernel code.
 455
 456           If you say N, all options in this submenu will be skipped and disabled.
 457
 458 if PARAVIRT_GUEST
 459
 460 source "arch/x86/xen/Kconfig"
 461
 462 config VMI
 463         bool "VMI Guest support"
 464         select PARAVIRT
 465         depends on X86_32
 466         ---help---
 467           VMI provides a paravirtualized interface to the VMware ESX server
 468           (it could be used by other hypervisors in theory too, but is not
 469           at the moment), by linking the kernel to a GPL-ed ROM module
 470           provided by the hypervisor.
 471
 472 config KVM_CLOCK
 473         bool "KVM paravirtualized clock"
 474         select PARAVIRT
 475         select PARAVIRT_CLOCK
 476         ---help---
 477           Turning on this option will allow you to run a paravirtualized clock
 478           when running over the KVM hypervisor. Instead of relying on a PIT
 479           (or probably other) emulation by the underlying device model, the host
 480           provides the guest with timing infrastructure such as time of day, and
 481           system time
 482
 483 config KVM_GUEST
 484         bool "KVM Guest support"
 485         select PARAVIRT
 486         ---help---
 487           This option enables various optimizations for running under the KVM
 488           hypervisor.
 489
 490 source "arch/x86/lguest/Kconfig"
 491
 492 config PARAVIRT
 493         bool "Enable paravirtualization code"
 494         ---help---
 495           This changes the kernel so it can modify itself when it is run
 496           under a hypervisor, potentially improving performance significantly
 497           over full virtualization.  However, when run without a hypervisor
 498           the kernel is theoretically slower and slightly larger.
 499
 500 config PARAVIRT_SPINLOCKS
 501         bool "Paravirtualization layer for spinlocks"
 502         depends on PARAVIRT && SMP && EXPERIMENTAL
 503         ---help---
 504           Paravirtualized spinlocks allow a pvops backend to replace the
 505           spinlock implementation with something virtualization-friendly
 506           (for example, block the virtual CPU rather than spinning).
 507
 508           Unfortunately the downside is an up to 5% performance hit on
 509           native kernels, with various workloads.
 510
 511           If you are unsure how to answer this question, answer N.
 512
 513 config PARAVIRT_CLOCK
 514         bool
 515         default n
 516
 517 endif
 518
 519 config PARAVIRT_DEBUG
 520         bool "paravirt-ops debugging"
 521         depends on PARAVIRT && DEBUG_KERNEL
 522         ---help---
 523           Enable to debug paravirt_ops internals.  Specifically, BUG if
 524           a paravirt_op is missing when it is called.
 525
 526 config MEMTEST
 527         bool "Memtest"
 528         ---help---
 529           This option adds a kernel parameter 'memtest', which allows memtest
 530           to be set.
 531                 memtest=0, mean disabled; -- default
 532                 memtest=1, mean do 1 test pattern;
 533                 ...
 534                 memtest=4, mean do 4 test patterns.
 535           If you are unsure how to answer this question, answer N.
 536
 537 config X86_SUMMIT_NUMA
 538         def_bool y
 539         depends on X86_32 && NUMA && X86_32_NON_STANDARD
 540
 541 config X86_CYCLONE_TIMER
 542         def_bool y
 543         depends on X86_32_NON_STANDARD
 544
 545 source "arch/x86/Kconfig.cpu"
 546
 547 config HPET_TIMER
 548         def_bool X86_64
 549         prompt "HPET Timer Support" if X86_32
 550         ---help---
 551           Use the IA-PC HPET (High Precision Event Timer) to manage
 552           time in preference to the PIT and RTC, if a HPET is
 553           present.
 554           HPET is the next generation timer replacing legacy 8254s.
 555           The HPET provides a stable time base on SMP
 556           systems, unlike the TSC, but it is more expensive to access,
 557           as it is off-chip.  You can find the HPET spec at
 558           <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
 559
 560           You can safely choose Y here.  However, HPET will only be
 561           activated if the platform and the BIOS support this feature.
 562           Otherwise the 8254 will be used for timing services.
 563
 564           Choose N to continue using the legacy 8254 timer.
 565
 566 config HPET_EMULATE_RTC
 567         def_bool y
 568         depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
 569
 570 # Mark as embedded because too many people got it wrong.
 571 # The code disables itself when not needed.
 572 config DMI
 573         default y
 574         bool "Enable DMI scanning" if EMBEDDED
 575         ---help---
 576           Enabled scanning of DMI to identify machine quirks. Say Y
 577           here unless you have verified that your setup is not
 578           affected by entries in the DMI blacklist. Required by PNP
 579           BIOS code.
 580
 581 config GART_IOMMU
 582         bool "GART IOMMU support" if EMBEDDED
 583         default y
 584         select SWIOTLB
 585         select AGP
 586         depends on X86_64 && PCI
 587         ---help---
 588           Support for full DMA access of devices with 32bit memory access only
 589           on systems with more than 3GB. This is usually needed for USB,
 590           sound, many IDE/SATA chipsets and some other devices.
 591           Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
 592           based hardware IOMMU and a software bounce buffer based IOMMU used
 593           on Intel systems and as fallback.
 594           The code is only active when needed (enough memory and limited
 595           device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
 596           too.
 597
 598 config CALGARY_IOMMU
 599         bool "IBM Calgary IOMMU support"
 600         select SWIOTLB
 601         depends on X86_64 && PCI && EXPERIMENTAL
 602         ---help---
 603           Support for hardware IOMMUs in IBM's xSeries x366 and x460
 604           systems. Needed to run systems with more than 3GB of memory
 605           properly with 32-bit PCI devices that do not support DAC
 606           (Double Address Cycle). Calgary also supports bus level
 607           isolation, where all DMAs pass through the IOMMU.  This
 608           prevents them from going anywhere except their intended
 609           destination. This catches hard-to-find kernel bugs and
 610           mis-behaving drivers and devices that do not use the DMA-API
 611           properly to set up their DMA buffers.  The IOMMU can be
 612           turned off at boot time with the iommu=off parameter.
 613           Normally the kernel will make the right choice by itself.
 614           If unsure, say Y.
 615
 616 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
 617         def_bool y
 618         prompt "Should Calgary be enabled by default?"
 619         depends on CALGARY_IOMMU
 620         ---help---
 621           Should Calgary be enabled by default? if you choose 'y', Calgary
 622           will be used (if it exists). If you choose 'n', Calgary will not be
 623           used even if it exists. If you choose 'n' and would like to use
 624           Calgary anyway, pass 'iommu=calgary' on the kernel command line.
 625           If unsure, say Y.
 626
 627 config AMD_IOMMU
 628         bool "AMD IOMMU support"
 629         select SWIOTLB
 630         select PCI_MSI
 631         depends on X86_64 && PCI && ACPI
 632         ---help---
 633           With this option you can enable support for AMD IOMMU hardware in
 634           your system. An IOMMU is a hardware component which provides
 635           remapping of DMA memory accesses from devices. With an AMD IOMMU you
 636           can isolate the the DMA memory of different devices and protect the
 637           system from misbehaving device drivers or hardware.
 638
 639           You can find out if your system has an AMD IOMMU if you look into
 640           your BIOS for an option to enable it or if you have an IVRS ACPI
 641           table.
 642
 643 config AMD_IOMMU_STATS
 644         bool "Export AMD IOMMU statistics to debugfs"
 645         depends on AMD_IOMMU
 646         select DEBUG_FS
 647         ---help---
 648           This option enables code in the AMD IOMMU driver to collect various
 649           statistics about whats happening in the driver and exports that
 650           information to userspace via debugfs.
 651           If unsure, say N.
 652
 653 # need this always selected by IOMMU for the VIA workaround
 654 config SWIOTLB
 655         def_bool y if X86_64
 656         ---help---
 657           Support for software bounce buffers used on x86-64 systems
 658           which don't have a hardware IOMMU (e.g. the current generation
 659           of Intel's x86-64 CPUs). Using this PCI devices which can only
 660           access 32-bits of memory can be used on systems with more than
 661           3 GB of memory. If unsure, say Y.
 662
 663 config IOMMU_HELPER
 664         def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
 665
 666 config IOMMU_API
 667         def_bool (AMD_IOMMU || DMAR)
 668
 669 config MAXSMP
 670         bool "Configure Maximum number of SMP Processors and NUMA Nodes"
 671         depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
 672         select CPUMASK_OFFSTACK
 673         default n
 674         ---help---
 675           Configure maximum number of CPUS and NUMA Nodes for this architecture.
 676           If unsure, say N.
 677
 678 config NR_CPUS
 679         int "Maximum number of CPUs" if SMP && !MAXSMP
 680         range 2 8 if SMP && X86_32 && !X86_BIGSMP
 681         range 2 512 if SMP && !MAXSMP
 682         default "1" if !SMP
 683         default "4096" if MAXSMP
 684         default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
 685         default "8" if SMP
 686         ---help---
 687           This allows you to specify the maximum number of CPUs which this
 688           kernel will support.  The maximum supported value is 512 and the
 689           minimum value which makes sense is 2.
 690
 691           This is purely to save memory - each supported CPU adds
 692           approximately eight kilobytes to the kernel image.
 693
 694 config SCHED_SMT
 695         bool "SMT (Hyperthreading) scheduler support"
 696         depends on X86_HT
 697         ---help---
 698           SMT scheduler support improves the CPU scheduler's decision making
 699           when dealing with Intel Pentium 4 chips with HyperThreading at a
 700           cost of slightly increased overhead in some places. If unsure say
 701           N here.
 702
 703 config SCHED_MC
 704         def_bool y
 705         prompt "Multi-core scheduler support"
 706         depends on X86_HT
 707         ---help---
 708           Multi-core scheduler support improves the CPU scheduler's decision
 709           making when dealing with multi-core CPU chips at a cost of slightly
 710           increased overhead in some places. If unsure say N here.
 711
 712 source "kernel/Kconfig.preempt"
 713
 714 config X86_UP_APIC
 715         bool "Local APIC support on uniprocessors"
 716         depends on X86_32 && !SMP && !X86_32_NON_STANDARD
 717         ---help---
 718           A local APIC (Advanced Programmable Interrupt Controller) is an
 719           integrated interrupt controller in the CPU. If you have a single-CPU
 720           system which has a processor with a local APIC, you can say Y here to
 721           enable and use it. If you say Y here even though your machine doesn't
 722           have a local APIC, then the kernel will still run with no slowdown at
 723           all. The local APIC supports CPU-generated self-interrupts (timer,
 724           performance counters), and the NMI watchdog which detects hard
 725           lockups.
 726
 727 config X86_UP_IOAPIC
 728         bool "IO-APIC support on uniprocessors"
 729         depends on X86_UP_APIC
 730         ---help---
 731           An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
 732           SMP-capable replacement for PC-style interrupt controllers. Most
 733           SMP systems and many recent uniprocessor systems have one.
 734
 735           If you have a single-CPU system with an IO-APIC, you can say Y here
 736           to use it. If you say Y here even though your machine doesn't have
 737           an IO-APIC, then the kernel will still run with no slowdown at all.
 738
 739 config X86_LOCAL_APIC
 740         def_bool y
 741         depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
 742         select HAVE_PERF_COUNTERS if (!M386 && !M486)
 743
 744 config X86_IO_APIC
 745         def_bool y
 746         depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
 747
 748 config X86_VISWS_APIC
 749         def_bool y
 750         depends on X86_32 && X86_VISWS
 751
 752 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
 753         bool "Reroute for broken boot IRQs"
 754         default n
 755         depends on X86_IO_APIC
 756         ---help---
 757           This option enables a workaround that fixes a source of
 758           spurious interrupts. This is recommended when threaded
 759           interrupt handling is used on systems where the generation of
 760           superfluous "boot interrupts" cannot be disabled.
 761
 762           Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
 763           entry in the chipset's IO-APIC is masked (as, e.g. the RT
 764           kernel does during interrupt handling). On chipsets where this
 765           boot IRQ generation cannot be disabled, this workaround keeps
 766           the original IRQ line masked so that only the equivalent "boot
 767           IRQ" is delivered to the CPUs. The workaround also tells the
 768           kernel to set up the IRQ handler on the boot IRQ line. In this
 769           way only one interrupt is delivered to the kernel. Otherwise
 770           the spurious second interrupt may cause the kernel to bring
 771           down (vital) interrupt lines.
 772
 773           Only affects "broken" chipsets. Interrupt sharing may be
 774           increased on these systems.
 775
 776 config X86_MCE
 777         bool "Machine Check Exception"
 778         ---help---
 779           Machine Check Exception support allows the processor to notify the
 780           kernel if it detects a problem (e.g. overheating, component failure).
 781           The action the kernel takes depends on the severity of the problem,
 782           ranging from a warning message on the console, to halting the machine.
 783           Your processor must be a Pentium or newer to support this - check the
 784           flags in /proc/cpuinfo for mce.  Note that some older Pentium systems
 785           have a design flaw which leads to false MCE events - hence MCE is
 786           disabled on all P5 processors, unless explicitly enabled with "mce"
 787           as a boot argument.  Similarly, if MCE is built in and creates a
 788           problem on some new non-standard machine, you can boot with "nomce"
 789           to disable it.  MCE support simply ignores non-MCE processors like
 790           the 386 and 486, so nearly everyone can say Y here.
 791
 792 config X86_OLD_MCE
 793         depends on X86_32 && X86_MCE
 794         bool "Use legacy machine check code (will go away)"
 795         default n
 796         select X86_ANCIENT_MCE
 797         ---help---
 798           Use the old i386 machine check code. This is merely intended for
 799           testing in a transition period. Try this if you run into any machine
 800           check related software problems, but report the problem to
 801           linux-kernel.  When in doubt say no.
 802
 803 config X86_NEW_MCE
 804         depends on X86_MCE
 805         bool
 806         default y if (!X86_OLD_MCE && X86_32) || X86_64
 807
 808 config X86_MCE_INTEL
 809         def_bool y
 810         prompt "Intel MCE features"
 811         depends on X86_NEW_MCE && X86_LOCAL_APIC
 812         ---help---
 813            Additional support for intel specific MCE features such as
 814            the thermal monitor.
 815
 816 config X86_MCE_AMD
 817         def_bool y
 818         prompt "AMD MCE features"
 819         depends on X86_NEW_MCE && X86_LOCAL_APIC
 820         ---help---
 821            Additional support for AMD specific MCE features such as
 822            the DRAM Error Threshold.
 823
 824 config X86_ANCIENT_MCE
 825         def_bool n
 826         depends on X86_32
 827         prompt "Support for old Pentium 5 / WinChip machine checks"
 828         ---help---
 829           Include support for machine check handling on old Pentium 5 or WinChip
 830           systems. These typically need to be enabled explicitely on the command
 831           line.
 832
 833 config X86_MCE_THRESHOLD
 834         depends on X86_MCE_AMD || X86_MCE_INTEL
 835         bool
 836         default y
 837
 838 config X86_MCE_INJECT
 839         depends on X86_NEW_MCE
 840         tristate "Machine check injector support"
 841         ---help---
 842           Provide support for injecting machine checks for testing purposes.
 843           If you don't know what a machine check is and you don't do kernel
 844           QA it is safe to say n.
 845
 846 config X86_MCE_NONFATAL
 847         tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
 848         depends on X86_OLD_MCE
 849         ---help---
 850           Enabling this feature starts a timer that triggers every 5 seconds which
 851           will look at the machine check registers to see if anything happened.
 852           Non-fatal problems automatically get corrected (but still logged).
 853           Disable this if you don't want to see these messages.
 854           Seeing the messages this option prints out may be indicative of dying
 855           or out-of-spec (ie, overclocked) hardware.
 856           This option only does something on certain CPUs.
 857           (AMD Athlon/Duron and Intel Pentium 4)
 858
 859 config X86_MCE_P4THERMAL
 860         bool "check for P4 thermal throttling interrupt."
 861         depends on X86_OLD_MCE && X86_MCE && (X86_UP_APIC || SMP)
 862         ---help---
 863           Enabling this feature will cause a message to be printed when the P4
 864           enters thermal throttling.
 865
 866 config X86_THERMAL_VECTOR
 867         def_bool y
 868         depends on X86_MCE_P4THERMAL || 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_SPARSEMEM_DEFAULT
1230         def_bool y
1231         depends on X86_64
1232
1233 config ARCH_SPARSEMEM_ENABLE
1234         def_bool y
1235         depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1236         select SPARSEMEM_STATIC if X86_32
1237         select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1238
1239 config ARCH_SELECT_MEMORY_MODEL
1240         def_bool y
1241         depends on ARCH_SPARSEMEM_ENABLE
1242
1243 config ARCH_MEMORY_PROBE
1244         def_bool X86_64
1245         depends on MEMORY_HOTPLUG
1246
1247 source "mm/Kconfig"
1248
1249 config HIGHPTE
1250         bool "Allocate 3rd-level pagetables from highmem"
1251         depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1252         ---help---
1253           The VM uses one page table entry for each page of physical memory.
1254           For systems with a lot of RAM, this can be wasteful of precious
1255           low memory.  Setting this option will put user-space page table
1256           entries in high memory.
1257
1258 config X86_CHECK_BIOS_CORRUPTION
1259         bool "Check for low memory corruption"
1260         ---help---
1261           Periodically check for memory corruption in low memory, which
1262           is suspected to be caused by BIOS.  Even when enabled in the
1263           configuration, it is disabled at runtime.  Enable it by
1264           setting "memory_corruption_check=1" on the kernel command
1265           line.  By default it scans the low 64k of memory every 60
1266           seconds; see the memory_corruption_check_size and
1267           memory_corruption_check_period parameters in
1268           Documentation/kernel-parameters.txt to adjust this.
1269
1270           When enabled with the default parameters, this option has
1271           almost no overhead, as it reserves a relatively small amount
1272           of memory and scans it infrequently.  It both detects corruption
1273           and prevents it from affecting the running system.
1274
1275           It is, however, intended as a diagnostic tool; if repeatable
1276           BIOS-originated corruption always affects the same memory,
1277           you can use memmap= to prevent the kernel from using that
1278           memory.
1279
1280 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1281         bool "Set the default setting of memory_corruption_check"
1282         depends on X86_CHECK_BIOS_CORRUPTION
1283         default y
1284         ---help---
1285           Set whether the default state of memory_corruption_check is
1286           on or off.
1287
1288 config X86_RESERVE_LOW_64K
1289         bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
1290         default y
1291         ---help---
1292           Reserve the first 64K of physical RAM on BIOSes that are known
1293           to potentially corrupt that memory range. A numbers of BIOSes are
1294           known to utilize this area during suspend/resume, so it must not
1295           be used by the kernel.
1296
1297           Set this to N if you are absolutely sure that you trust the BIOS
1298           to get all its memory reservations and usages right.
1299
1300           If you have doubts about the BIOS (e.g. suspend/resume does not
1301           work or there's kernel crashes after certain hardware hotplug
1302           events) and it's not AMI or Phoenix, then you might want to enable
1303           X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
1304           corruption patterns.
1305
1306           Say Y if unsure.
1307
1308 config MATH_EMULATION
1309         bool
1310         prompt "Math emulation" if X86_32
1311         ---help---
1312           Linux can emulate a math coprocessor (used for floating point
1313           operations) if you don't have one. 486DX and Pentium processors have
1314           a math coprocessor built in, 486SX and 386 do not, unless you added
1315           a 487DX or 387, respectively. (The messages during boot time can
1316           give you some hints here ["man dmesg"].) Everyone needs either a
1317           coprocessor or this emulation.
1318
1319           If you don't have a math coprocessor, you need to say Y here; if you
1320           say Y here even though you have a coprocessor, the coprocessor will
1321           be used nevertheless. (This behavior can be changed with the kernel
1322           command line option "no387", which comes handy if your coprocessor
1323           is broken. Try "man bootparam" or see the documentation of your boot
1324           loader (lilo or loadlin) about how to pass options to the kernel at
1325           boot time.) This means that it is a good idea to say Y here if you
1326           intend to use this kernel on different machines.
1327
1328           More information about the internals of the Linux math coprocessor
1329           emulation can be found in <file:arch/x86/math-emu/README>.
1330
1331           If you are not sure, say Y; apart from resulting in a 66 KB bigger
1332           kernel, it won't hurt.
1333
1334 config MTRR
1335         bool "MTRR (Memory Type Range Register) support"
1336         ---help---
1337           On Intel P6 family processors (Pentium Pro, Pentium II and later)
1338           the Memory Type Range Registers (MTRRs) may be used to control
1339           processor access to memory ranges. This is most useful if you have
1340           a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1341           allows bus write transfers to be combined into a larger transfer
1342           before bursting over the PCI/AGP bus. This can increase performance
1343           of image write operations 2.5 times or more. Saying Y here creates a
1344           /proc/mtrr file which may be used to manipulate your processor's
1345           MTRRs. Typically the X server should use this.
1346
1347           This code has a reasonably generic interface so that similar
1348           control registers on other processors can be easily supported
1349           as well:
1350
1351           The Cyrix 6x86, 6x86MX and M II processors have Address Range
1352           Registers (ARRs) which provide a similar functionality to MTRRs. For
1353           these, the ARRs are used to emulate the MTRRs.
1354           The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1355           MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1356           write-combining. All of these processors are supported by this code
1357           and it makes sense to say Y here if you have one of them.
1358
1359           Saying Y here also fixes a problem with buggy SMP BIOSes which only
1360           set the MTRRs for the boot CPU and not for the secondary CPUs. This
1361           can lead to all sorts of problems, so it's good to say Y here.
1362
1363           You can safely say Y even if your machine doesn't have MTRRs, you'll
1364           just add about 9 KB to your kernel.
1365
1366           See <file:Documentation/x86/mtrr.txt> for more information.
1367
1368 config MTRR_SANITIZER
1369         def_bool y
1370         prompt "MTRR cleanup support"
1371         depends on MTRR
1372         ---help---
1373           Convert MTRR layout from continuous to discrete, so X drivers can
1374           add writeback entries.
1375
1376           Can be disabled with disable_mtrr_cleanup on the kernel command line.
1377           The largest mtrr entry size for a continuous block can be set with
1378           mtrr_chunk_size.
1379
1380           If unsure, say Y.
1381
1382 config MTRR_SANITIZER_ENABLE_DEFAULT
1383         int "MTRR cleanup enable value (0-1)"
1384         range 0 1
1385         default "0"
1386         depends on MTRR_SANITIZER
1387         ---help---
1388           Enable mtrr cleanup default value
1389
1390 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1391         int "MTRR cleanup spare reg num (0-7)"
1392         range 0 7
1393         default "1"
1394         depends on MTRR_SANITIZER
1395         ---help---
1396           mtrr cleanup spare entries default, it can be changed via
1397           mtrr_spare_reg_nr=N on the kernel command line.
1398
1399 config X86_PAT
1400         bool
1401         prompt "x86 PAT support"
1402         depends on MTRR
1403         ---help---
1404           Use PAT attributes to setup page level cache control.
1405
1406           PATs are the modern equivalents of MTRRs and are much more
1407           flexible than MTRRs.
1408
1409           Say N here if you see bootup problems (boot crash, boot hang,
1410           spontaneous reboots) or a non-working video driver.
1411
1412           If unsure, say Y.
1413
1414 config EFI
1415         bool "EFI runtime service support"
1416         depends on ACPI
1417         ---help---
1418           This enables the kernel to use EFI runtime services that are
1419           available (such as the EFI variable services).
1420
1421           This option is only useful on systems that have EFI firmware.
1422           In addition, you should use the latest ELILO loader available
1423           at <http://elilo.sourceforge.net> in order to take advantage
1424           of EFI runtime services. However, even with this option, the
1425           resultant kernel should continue to boot on existing non-EFI
1426           platforms.
1427
1428 config SECCOMP
1429         def_bool y
1430         prompt "Enable seccomp to safely compute untrusted bytecode"
1431         ---help---
1432           This kernel feature is useful for number crunching applications
1433           that may need to compute untrusted bytecode during their
1434           execution. By using pipes or other transports made available to
1435           the process as file descriptors supporting the read/write
1436           syscalls, it's possible to isolate those applications in
1437           their own address space using seccomp. Once seccomp is
1438           enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1439           and the task is only allowed to execute a few safe syscalls
1440           defined by each seccomp mode.
1441
1442           If unsure, say Y. Only embedded should say N here.
1443
1444 config CC_STACKPROTECTOR_ALL
1445         bool
1446
1447 config CC_STACKPROTECTOR
1448         bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1449         select CC_STACKPROTECTOR_ALL
1450         ---help---
1451           This option turns on the -fstack-protector GCC feature. This
1452           feature puts, at the beginning of functions, a canary value on
1453           the stack just before the return address, and validates
1454           the value just before actually returning.  Stack based buffer
1455           overflows (that need to overwrite this return address) now also
1456           overwrite the canary, which gets detected and the attack is then
1457           neutralized via a kernel panic.
1458
1459           This feature requires gcc version 4.2 or above, or a distribution
1460           gcc with the feature backported. Older versions are automatically
1461           detected and for those versions, this configuration option is
1462           ignored. (and a warning is printed during bootup)
1463
1464 source kernel/Kconfig.hz
1465
1466 config KEXEC
1467         bool "kexec system call"
1468         ---help---
1469           kexec is a system call that implements the ability to shutdown your
1470           current kernel, and to start another kernel.  It is like a reboot
1471           but it is independent of the system firmware.   And like a reboot
1472           you can start any kernel with it, not just Linux.
1473
1474           The name comes from the similarity to the exec system call.
1475
1476           It is an ongoing process to be certain the hardware in a machine
1477           is properly shutdown, so do not be surprised if this code does not
1478           initially work for you.  It may help to enable device hotplugging
1479           support.  As of this writing the exact hardware interface is
1480           strongly in flux, so no good recommendation can be made.
1481
1482 config CRASH_DUMP
1483         bool "kernel crash dumps"
1484         depends on X86_64 || (X86_32 && HIGHMEM)
1485         ---help---
1486           Generate crash dump after being started by kexec.
1487           This should be normally only set in special crash dump kernels
1488           which are loaded in the main kernel with kexec-tools into
1489           a specially reserved region and then later executed after
1490           a crash by kdump/kexec. The crash dump kernel must be compiled
1491           to a memory address not used by the main kernel or BIOS using
1492           PHYSICAL_START, or it must be built as a relocatable image
1493           (CONFIG_RELOCATABLE=y).
1494           For more details see Documentation/kdump/kdump.txt
1495
1496 config KEXEC_JUMP
1497         bool "kexec jump (EXPERIMENTAL)"
1498         depends on EXPERIMENTAL
1499         depends on KEXEC && HIBERNATION
1500         ---help---
1501           Jump between original kernel and kexeced kernel and invoke
1502           code in physical address mode via KEXEC
1503
1504 config PHYSICAL_START
1505         hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1506         default "0x1000000"
1507         ---help---
1508           This gives the physical address where the kernel is loaded.
1509
1510           If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1511           bzImage will decompress itself to above physical address and
1512           run from there. Otherwise, bzImage will run from the address where
1513           it has been loaded by the boot loader and will ignore above physical
1514           address.
1515
1516           In normal kdump cases one does not have to set/change this option
1517           as now bzImage can be compiled as a completely relocatable image
1518           (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1519           address. This option is mainly useful for the folks who don't want
1520           to use a bzImage for capturing the crash dump and want to use a
1521           vmlinux instead. vmlinux is not relocatable hence a kernel needs
1522           to be specifically compiled to run from a specific memory area
1523           (normally a reserved region) and this option comes handy.
1524
1525           So if you are using bzImage for capturing the crash dump,
1526           leave the value here unchanged to 0x1000000 and set
1527           CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
1528           for capturing the crash dump change this value to start of
1529           the reserved region.  In other words, it can be set based on
1530           the "X" value as specified in the "crashkernel=YM@XM"
1531           command line boot parameter passed to the panic-ed
1532           kernel. Please take a look at Documentation/kdump/kdump.txt
1533           for more details about crash dumps.
1534
1535           Usage of bzImage for capturing the crash dump is recommended as
1536           one does not have to build two kernels. Same kernel can be used
1537           as production kernel and capture kernel. Above option should have
1538           gone away after relocatable bzImage support is introduced. But it
1539           is present because there are users out there who continue to use
1540           vmlinux for dump capture. This option should go away down the
1541           line.
1542
1543           Don't change this unless you know what you are doing.
1544
1545 config RELOCATABLE
1546         bool "Build a relocatable kernel"
1547         default y
1548         ---help---
1549           This builds a kernel image that retains relocation information
1550           so it can be loaded someplace besides the default 1MB.
1551           The relocations tend to make the kernel binary about 10% larger,
1552           but are discarded at runtime.
1553
1554           One use is for the kexec on panic case where the recovery kernel
1555           must live at a different physical address than the primary
1556           kernel.
1557
1558           Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1559           it has been loaded at and the compile time physical address
1560           (CONFIG_PHYSICAL_START) is ignored.
1561
1562 # Relocation on x86-32 needs some additional build support
1563 config X86_NEED_RELOCS
1564         def_bool y
1565         depends on X86_32 && RELOCATABLE
1566
1567 config PHYSICAL_ALIGN
1568         hex
1569         prompt "Alignment value to which kernel should be aligned" if X86_32
1570         default "0x1000000"
1571         range 0x2000 0x1000000
1572         ---help---
1573           This value puts the alignment restrictions on physical address
1574           where kernel is loaded and run from. Kernel is compiled for an
1575           address which meets above alignment restriction.
1576
1577           If bootloader loads the kernel at a non-aligned address and
1578           CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1579           address aligned to above value and run from there.
1580
1581           If bootloader loads the kernel at a non-aligned address and
1582           CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1583           load address and decompress itself to the address it has been
1584           compiled for and run from there. The address for which kernel is
1585           compiled already meets above alignment restrictions. Hence the
1586           end result is that kernel runs from a physical address meeting
1587           above alignment restrictions.
1588
1589           Don't change this unless you know what you are doing.
1590
1591 config HOTPLUG_CPU
1592         bool "Support for hot-pluggable CPUs"
1593         depends on SMP && HOTPLUG
1594         ---help---
1595           Say Y here to allow turning CPUs off and on. CPUs can be
1596           controlled through /sys/devices/system/cpu.
1597           ( Note: power management support will enable this option
1598             automatically on SMP systems. )
1599           Say N if you want to disable CPU hotplug.
1600
1601 config COMPAT_VDSO
1602         def_bool y
1603         prompt "Compat VDSO support"
1604         depends on X86_32 || IA32_EMULATION
1605         ---help---
1606           Map the 32-bit VDSO to the predictable old-style address too.
1607         ---help---
1608           Say N here if you are running a sufficiently recent glibc
1609           version (2.3.3 or later), to remove the high-mapped
1610           VDSO mapping and to exclusively use the randomized VDSO.
1611
1612           If unsure, say Y.
1613
1614 config CMDLINE_BOOL
1615         bool "Built-in kernel command line"
1616         default n
1617         ---help---
1618           Allow for specifying boot arguments to the kernel at
1619           build time.  On some systems (e.g. embedded ones), it is
1620           necessary or convenient to provide some or all of the
1621           kernel boot arguments with the kernel itself (that is,
1622           to not rely on the boot loader to provide them.)
1623
1624           To compile command line arguments into the kernel,
1625           set this option to 'Y', then fill in the
1626           the boot arguments in CONFIG_CMDLINE.
1627
1628           Systems with fully functional boot loaders (i.e. non-embedded)
1629           should leave this option set to 'N'.
1630
1631 config CMDLINE
1632         string "Built-in kernel command string"
1633         depends on CMDLINE_BOOL
1634         default ""
1635         ---help---
1636           Enter arguments here that should be compiled into the kernel
1637           image and used at boot time.  If the boot loader provides a
1638           command line at boot time, it is appended to this string to
1639           form the full kernel command line, when the system boots.
1640
1641           However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1642           change this behavior.
1643
1644           In most cases, the command line (whether built-in or provided
1645           by the boot loader) should specify the device for the root
1646           file system.
1647
1648 config CMDLINE_OVERRIDE
1649         bool "Built-in command line overrides boot loader arguments"
1650         default n
1651         depends on CMDLINE_BOOL
1652         ---help---
1653           Set this option to 'Y' to have the kernel ignore the boot loader
1654           command line, and use ONLY the built-in command line.
1655
1656           This is used to work around broken boot loaders.  This should
1657           be set to 'N' under normal conditions.
1658
1659 endmenu
1660
1661 config ARCH_ENABLE_MEMORY_HOTPLUG
1662         def_bool y
1663         depends on X86_64 || (X86_32 && HIGHMEM)
1664
1665 config ARCH_ENABLE_MEMORY_HOTREMOVE
1666         def_bool y
1667         depends on MEMORY_HOTPLUG
1668
1669 config HAVE_ARCH_EARLY_PFN_TO_NID
1670         def_bool X86_64
1671         depends on NUMA
1672
1673 menu "Power management and ACPI options"
1674
1675 config ARCH_HIBERNATION_HEADER
1676         def_bool y
1677         depends on X86_64 && HIBERNATION
1678
1679 source "kernel/power/Kconfig"
1680
1681 source "drivers/acpi/Kconfig"
1682
1683 config X86_APM_BOOT
1684         bool
1685         default y
1686         depends on APM || APM_MODULE
1687
1688 menuconfig APM
1689         tristate "APM (Advanced Power Management) BIOS support"
1690         depends on X86_32 && PM_SLEEP
1691         ---help---
1692           APM is a BIOS specification for saving power using several different
1693           techniques. This is mostly useful for battery powered laptops with
1694           APM compliant BIOSes. If you say Y here, the system time will be
1695           reset after a RESUME operation, the /proc/apm device will provide
1696           battery status information, and user-space programs will receive
1697           notification of APM "events" (e.g. battery status change).
1698
1699           If you select "Y" here, you can disable actual use of the APM
1700           BIOS by passing the "apm=off" option to the kernel at boot time.
1701
1702           Note that the APM support is almost completely disabled for
1703           machines with more than one CPU.
1704
1705           In order to use APM, you will need supporting software. For location
1706           and more information, read <file:Documentation/power/pm.txt> and the
1707           Battery Powered Linux mini-HOWTO, available from
1708           <http://www.tldp.org/docs.html#howto>.
1709
1710           This driver does not spin down disk drives (see the hdparm(8)
1711           manpage ("man 8 hdparm") for that), and it doesn't turn off
1712           VESA-compliant "green" monitors.
1713
1714           This driver does not support the TI 4000M TravelMate and the ACER
1715           486/DX4/75 because they don't have compliant BIOSes. Many "green"
1716           desktop machines also don't have compliant BIOSes, and this driver
1717           may cause those machines to panic during the boot phase.
1718
1719           Generally, if you don't have a battery in your machine, there isn't
1720           much point in using this driver and you should say N. If you get
1721           random kernel OOPSes or reboots that don't seem to be related to
1722           anything, try disabling/enabling this option (or disabling/enabling
1723           APM in your BIOS).
1724
1725           Some other things you should try when experiencing seemingly random,
1726           "weird" problems:
1727
1728           1) make sure that you have enough swap space and that it is
1729           enabled.
1730           2) pass the "no-hlt" option to the kernel
1731           3) switch on floating point emulation in the kernel and pass
1732           the "no387" option to the kernel
1733           4) pass the "floppy=nodma" option to the kernel
1734           5) pass the "mem=4M" option to the kernel (thereby disabling
1735           all but the first 4 MB of RAM)
1736           6) make sure that the CPU is not over clocked.
1737           7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1738           8) disable the cache from your BIOS settings
1739           9) install a fan for the video card or exchange video RAM
1740           10) install a better fan for the CPU
1741           11) exchange RAM chips
1742           12) exchange the motherboard.
1743
1744           To compile this driver as a module, choose M here: the
1745           module will be called apm.
1746
1747 if APM
1748
1749 config APM_IGNORE_USER_SUSPEND
1750         bool "Ignore USER SUSPEND"
1751         ---help---
1752           This option will ignore USER SUSPEND requests. On machines with a
1753           compliant APM BIOS, you want to say N. However, on the NEC Versa M
1754           series notebooks, it is necessary to say Y because of a BIOS bug.
1755
1756 config APM_DO_ENABLE
1757         bool "Enable PM at boot time"
1758         ---help---
1759           Enable APM features at boot time. From page 36 of the APM BIOS
1760           specification: "When disabled, the APM BIOS does not automatically
1761           power manage devices, enter the Standby State, enter the Suspend
1762           State, or take power saving steps in response to CPU Idle calls."
1763           This driver will make CPU Idle calls when Linux is idle (unless this
1764           feature is turned off -- see "Do CPU IDLE calls", below). This
1765           should always save battery power, but more complicated APM features
1766           will be dependent on your BIOS implementation. You may need to turn
1767           this option off if your computer hangs at boot time when using APM
1768           support, or if it beeps continuously instead of suspending. Turn
1769           this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1770           T400CDT. This is off by default since most machines do fine without
1771           this feature.
1772
1773 config APM_CPU_IDLE
1774         bool "Make CPU Idle calls when idle"
1775         ---help---
1776           Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1777           On some machines, this can activate improved power savings, such as
1778           a slowed CPU clock rate, when the machine is idle. These idle calls
1779           are made after the idle loop has run for some length of time (e.g.,
1780           333 mS). On some machines, this will cause a hang at boot time or
1781           whenever the CPU becomes idle. (On machines with more than one CPU,
1782           this option does nothing.)
1783
1784 config APM_DISPLAY_BLANK
1785         bool "Enable console blanking using APM"
1786         ---help---
1787           Enable console blanking using the APM. Some laptops can use this to
1788           turn off the LCD backlight when the screen blanker of the Linux
1789           virtual console blanks the screen. Note that this is only used by
1790           the virtual console screen blanker, and won't turn off the backlight
1791           when using the X Window system. This also doesn't have anything to
1792           do with your VESA-compliant power-saving monitor. Further, this
1793           option doesn't work for all laptops -- it might not turn off your
1794           backlight at all, or it might print a lot of errors to the console,
1795           especially if you are using gpm.
1796
1797 config APM_ALLOW_INTS
1798         bool "Allow interrupts during APM BIOS calls"
1799         ---help---
1800           Normally we disable external interrupts while we are making calls to
1801           the APM BIOS as a measure to lessen the effects of a badly behaving
1802           BIOS implementation.  The BIOS should reenable interrupts if it
1803           needs to.  Unfortunately, some BIOSes do not -- especially those in
1804           many of the newer IBM Thinkpads.  If you experience hangs when you
1805           suspend, try setting this to Y.  Otherwise, say N.
1806
1807 endif # APM
1808
1809 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1810
1811 source "drivers/cpuidle/Kconfig"
1812
1813 source "drivers/idle/Kconfig"
1814
1815 endmenu
1816
1817
1818 menu "Bus options (PCI etc.)"
1819
1820 config PCI
1821         bool "PCI support"
1822         default y
1823         select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1824         ---help---
1825           Find out whether you have a PCI motherboard. PCI is the name of a
1826           bus system, i.e. the way the CPU talks to the other stuff inside
1827           your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1828           VESA. If you have PCI, say Y, otherwise N.
1829
1830 choice
1831         prompt "PCI access mode"
1832         depends on X86_32 && PCI
1833         default PCI_GOANY
1834         ---help---
1835           On PCI systems, the BIOS can be used to detect the PCI devices and
1836           determine their configuration. However, some old PCI motherboards
1837           have BIOS bugs and may crash if this is done. Also, some embedded
1838           PCI-based systems don't have any BIOS at all. Linux can also try to
1839           detect the PCI hardware directly without using the BIOS.
1840
1841           With this option, you can specify how Linux should detect the
1842           PCI devices. If you choose "BIOS", the BIOS will be used,
1843           if you choose "Direct", the BIOS won't be used, and if you
1844           choose "MMConfig", then PCI Express MMCONFIG will be used.
1845           If you choose "Any", the kernel will try MMCONFIG, then the
1846           direct access method and falls back to the BIOS if that doesn't
1847           work. If unsure, go with the default, which is "Any".
1848
1849 config PCI_GOBIOS
1850         bool "BIOS"
1851
1852 config PCI_GOMMCONFIG
1853         bool "MMConfig"
1854
1855 config PCI_GODIRECT
1856         bool "Direct"
1857
1858 config PCI_GOOLPC
1859         bool "OLPC"
1860         depends on OLPC
1861
1862 config PCI_GOANY
1863         bool "Any"
1864
1865 endchoice
1866
1867 config PCI_BIOS
1868         def_bool y
1869         depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1870
1871 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1872 config PCI_DIRECT
1873         def_bool y
1874         depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1875
1876 config PCI_MMCONFIG
1877         def_bool y
1878         depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1879
1880 config PCI_OLPC
1881         def_bool y
1882         depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1883
1884 config PCI_DOMAINS
1885         def_bool y
1886         depends on PCI
1887
1888 config PCI_MMCONFIG
1889         bool "Support mmconfig PCI config space access"
1890         depends on X86_64 && PCI && ACPI
1891
1892 config DMAR
1893         bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1894         depends on PCI_MSI && ACPI && EXPERIMENTAL
1895         help
1896           DMA remapping (DMAR) devices support enables independent address
1897           translations for Direct Memory Access (DMA) from devices.
1898           These DMA remapping devices are reported via ACPI tables
1899           and include PCI device scope covered by these DMA
1900           remapping devices.
1901
1902 config DMAR_DEFAULT_ON
1903         def_bool y
1904         prompt "Enable DMA Remapping Devices by default"
1905         depends on DMAR
1906         help
1907           Selecting this option will enable a DMAR device at boot time if
1908           one is found. If this option is not selected, DMAR support can
1909           be enabled by passing intel_iommu=on to the kernel. It is
1910           recommended you say N here while the DMAR code remains
1911           experimental.
1912
1913 config DMAR_GFX_WA
1914         def_bool y
1915         prompt "Support for Graphics workaround"
1916         depends on DMAR
1917         ---help---
1918           Current Graphics drivers tend to use physical address
1919           for DMA and avoid using DMA APIs. Setting this config
1920           option permits the IOMMU driver to set a unity map for
1921           all the OS-visible memory. Hence the driver can continue
1922           to use physical addresses for DMA.
1923
1924 config DMAR_FLOPPY_WA
1925         def_bool y
1926         depends on DMAR
1927         ---help---
1928           Floppy disk drivers are know to bypass DMA API calls
1929           thereby failing to work when IOMMU is enabled. This
1930           workaround will setup a 1:1 mapping for the first
1931           16M to make floppy (an ISA device) work.
1932
1933 config INTR_REMAP
1934         bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1935         depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
1936         ---help---
1937           Supports Interrupt remapping for IO-APIC and MSI devices.
1938           To use x2apic mode in the CPU's which support x2APIC enhancements or
1939           to support platforms with CPU's having > 8 bit APIC ID, say Y.
1940
1941 source "drivers/pci/pcie/Kconfig"
1942
1943 source "drivers/pci/Kconfig"
1944
1945 # x86_64 have no ISA slots, but do have ISA-style DMA.
1946 config ISA_DMA_API
1947         def_bool y
1948
1949 if X86_32
1950
1951 config ISA
1952         bool "ISA support"
1953         ---help---
1954           Find out whether you have ISA slots on your motherboard.  ISA is the
1955           name of a bus system, i.e. the way the CPU talks to the other stuff
1956           inside your box.  Other bus systems are PCI, EISA, MicroChannel
1957           (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
1958           newer boards don't support it.  If you have ISA, say Y, otherwise N.
1959
1960 config EISA
1961         bool "EISA support"
1962         depends on ISA
1963         ---help---
1964           The Extended Industry Standard Architecture (EISA) bus was
1965           developed as an open alternative to the IBM MicroChannel bus.
1966
1967           The EISA bus provided some of the features of the IBM MicroChannel
1968           bus while maintaining backward compatibility with cards made for
1969           the older ISA bus.  The EISA bus saw limited use between 1988 and
1970           1995 when it was made obsolete by the PCI bus.
1971
1972           Say Y here if you are building a kernel for an EISA-based machine.
1973
1974           Otherwise, say N.
1975
1976 source "drivers/eisa/Kconfig"
1977
1978 config MCA
1979         bool "MCA support"
1980         ---help---
1981           MicroChannel Architecture is found in some IBM PS/2 machines and
1982           laptops.  It is a bus system similar to PCI or ISA. See
1983           <file:Documentation/mca.txt> (and especially the web page given
1984           there) before attempting to build an MCA bus kernel.
1985
1986 source "drivers/mca/Kconfig"
1987
1988 config SCx200
1989         tristate "NatSemi SCx200 support"
1990         ---help---
1991           This provides basic support for National Semiconductor's
1992           (now AMD's) Geode processors.  The driver probes for the
1993           PCI-IDs of several on-chip devices, so its a good dependency
1994           for other scx200_* drivers.
1995
1996           If compiled as a module, the driver is named scx200.
1997
1998 config SCx200HR_TIMER
1999         tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2000         depends on SCx200 && GENERIC_TIME
2001         default y
2002         ---help---
2003           This driver provides a clocksource built upon the on-chip
2004           27MHz high-resolution timer.  Its also a workaround for
2005           NSC Geode SC-1100's buggy TSC, which loses time when the
2006           processor goes idle (as is done by the scheduler).  The
2007           other workaround is idle=poll boot option.
2008
2009 config GEODE_MFGPT_TIMER
2010         def_bool y
2011         prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
2012         depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
2013         ---help---
2014           This driver provides a clock event source based on the MFGPT
2015           timer(s) in the CS5535 and CS5536 companion chip for the geode.
2016           MFGPTs have a better resolution and max interval than the
2017           generic PIT, and are suitable for use as high-res timers.
2018
2019 config OLPC
2020         bool "One Laptop Per Child support"
2021         default n
2022         ---help---
2023           Add support for detecting the unique features of the OLPC
2024           XO hardware.
2025
2026 endif # X86_32
2027
2028 config K8_NB
2029         def_bool y
2030         depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
2031
2032 source "drivers/pcmcia/Kconfig"
2033
2034 source "drivers/pci/hotplug/Kconfig"
2035
2036 endmenu
2037
2038
2039 menu "Executable file formats / Emulations"
2040
2041 source "fs/Kconfig.binfmt"
2042
2043 config IA32_EMULATION
2044         bool "IA32 Emulation"
2045         depends on X86_64
2046         select COMPAT_BINFMT_ELF
2047         ---help---
2048           Include code to run 32-bit programs under a 64-bit kernel. You should
2049           likely turn this on, unless you're 100% sure that you don't have any
2050           32-bit programs left.
2051
2052 config IA32_AOUT
2053         tristate "IA32 a.out support"
2054         depends on IA32_EMULATION
2055         ---help---
2056           Support old a.out binaries in the 32bit emulation.
2057
2058 config COMPAT
2059         def_bool y
2060         depends on IA32_EMULATION
2061
2062 config COMPAT_FOR_U64_ALIGNMENT
2063         def_bool COMPAT
2064         depends on X86_64
2065
2066 config SYSVIPC_COMPAT
2067         def_bool y
2068         depends on COMPAT && SYSVIPC
2069
2070 endmenu
2071
2072
2073 config HAVE_ATOMIC_IOMAP
2074         def_bool y
2075         depends on X86_32
2076
2077 source "net/Kconfig"
2078
2079 source "drivers/Kconfig"
2080
2081 source "drivers/firmware/Kconfig"
2082
2083 source "fs/Kconfig"
2084
2085 source "arch/x86/Kconfig.debug"
2086
2087 source "security/Kconfig"
2088
2089 source "crypto/Kconfig"
2090
2091 source "arch/x86/kvm/Kconfig"
2092
2093 source "lib/Kconfig"