arch/x86/Kconfig

   1 # Select 32 or 64 bit
   2 config 64BIT
   3         bool "64-bit kernel" if ARCH = "x86"
   4         default ARCH = "x86_64"
   5         ---help---
   6           Say yes to build a 64-bit kernel - formerly known as x86_64
   7           Say no to build a 32-bit kernel - formerly known as i386
   8
   9 config X86_32
  10         def_bool !64BIT
  11
  12 config X86_64
  13         def_bool 64BIT
  14
  15 ### Arch settings
  16 config X86
  17         def_bool y
  18         select HAVE_AOUT if X86_32
  19         select HAVE_READQ
  20         select HAVE_WRITEQ
  21         select HAVE_UNSTABLE_SCHED_CLOCK
  22         select HAVE_IDE
  23         select HAVE_OPROFILE
  24         select HAVE_PERF_EVENTS
  25         select HAVE_IRQ_WORK
  26         select HAVE_IOREMAP_PROT
  27         select HAVE_KPROBES
  28         select HAVE_MEMBLOCK
  29         select ARCH_WANT_OPTIONAL_GPIOLIB
  30         select ARCH_WANT_FRAME_POINTERS
  31         select HAVE_DMA_ATTRS
  32         select HAVE_KRETPROBES
  33         select HAVE_OPTPROBES
  34         select HAVE_FTRACE_MCOUNT_RECORD
  35         select HAVE_C_RECORDMCOUNT
  36         select HAVE_DYNAMIC_FTRACE
  37         select HAVE_FUNCTION_TRACER
  38         select HAVE_FUNCTION_GRAPH_TRACER
  39         select HAVE_FUNCTION_GRAPH_FP_TEST
  40         select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  41         select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
  42         select HAVE_SYSCALL_TRACEPOINTS
  43         select HAVE_KVM
  44         select HAVE_ARCH_KGDB
  45         select HAVE_ARCH_TRACEHOOK
  46         select HAVE_GENERIC_DMA_COHERENT if X86_32
  47         select HAVE_EFFICIENT_UNALIGNED_ACCESS
  48         select USER_STACKTRACE_SUPPORT
  49         select HAVE_REGS_AND_STACK_ACCESS_API
  50         select HAVE_DMA_API_DEBUG
  51         select HAVE_KERNEL_GZIP
  52         select HAVE_KERNEL_BZIP2
  53         select HAVE_KERNEL_LZMA
  54         select HAVE_KERNEL_XZ
  55         select HAVE_KERNEL_LZO
  56         select HAVE_HW_BREAKPOINT
  57         select HAVE_MIXED_BREAKPOINTS_REGS
  58         select PERF_EVENTS
  59         select HAVE_PERF_EVENTS_NMI
  60         select ANON_INODES
  61         select HAVE_ARCH_KMEMCHECK
  62         select HAVE_USER_RETURN_NOTIFIER
  63         select HAVE_ARCH_JUMP_LABEL
  64         select HAVE_TEXT_POKE_SMP
  65         select HAVE_GENERIC_HARDIRQS
  66         select HAVE_SPARSE_IRQ
  67         select GENERIC_IRQ_PROBE
  68         select GENERIC_PENDING_IRQ if SMP
  69         select USE_GENERIC_SMP_HELPERS if SMP
  70
  71 config INSTRUCTION_DECODER
  72         def_bool (KPROBES || PERF_EVENTS)
  73
  74 config OUTPUT_FORMAT
  75         string
  76         default "elf32-i386" if X86_32
  77         default "elf64-x86-64" if X86_64
  78
  79 config ARCH_DEFCONFIG
  80         string
  81         default "arch/x86/configs/i386_defconfig" if X86_32
  82         default "arch/x86/configs/x86_64_defconfig" if X86_64
  83
  84 config GENERIC_CMOS_UPDATE
  85         def_bool y
  86
  87 config CLOCKSOURCE_WATCHDOG
  88         def_bool y
  89
  90 config GENERIC_CLOCKEVENTS
  91         def_bool y
  92
  93 config GENERIC_CLOCKEVENTS_BROADCAST
  94         def_bool y
  95         depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  96
  97 config LOCKDEP_SUPPORT
  98         def_bool y
  99
 100 config STACKTRACE_SUPPORT
 101         def_bool y
 102
 103 config HAVE_LATENCYTOP_SUPPORT
 104         def_bool y
 105
 106 config MMU
 107         def_bool y
 108
 109 config ZONE_DMA
 110         def_bool y
 111
 112 config SBUS
 113         bool
 114
 115 config NEED_DMA_MAP_STATE
 116        def_bool (X86_64 || DMAR || DMA_API_DEBUG)
 117
 118 config NEED_SG_DMA_LENGTH
 119         def_bool y
 120
 121 config GENERIC_ISA_DMA
 122         def_bool y
 123
 124 config GENERIC_IOMAP
 125         def_bool y
 126
 127 config GENERIC_BUG
 128         def_bool y
 129         depends on BUG
 130         select GENERIC_BUG_RELATIVE_POINTERS if X86_64
 131
 132 config GENERIC_BUG_RELATIVE_POINTERS
 133         bool
 134
 135 config GENERIC_HWEIGHT
 136         def_bool y
 137
 138 config GENERIC_GPIO
 139         bool
 140
 141 config ARCH_MAY_HAVE_PC_FDC
 142         def_bool y
 143
 144 config RWSEM_GENERIC_SPINLOCK
 145         def_bool !X86_XADD
 146
 147 config RWSEM_XCHGADD_ALGORITHM
 148         def_bool X86_XADD
 149
 150 config ARCH_HAS_CPU_IDLE_WAIT
 151         def_bool y
 152
 153 config GENERIC_CALIBRATE_DELAY
 154         def_bool y
 155
 156 config GENERIC_TIME_VSYSCALL
 157         bool
 158         default X86_64
 159
 160 config ARCH_HAS_CPU_RELAX
 161         def_bool y
 162
 163 config ARCH_HAS_DEFAULT_IDLE
 164         def_bool y
 165
 166 config ARCH_HAS_CACHE_LINE_SIZE
 167         def_bool y
 168
 169 config HAVE_SETUP_PER_CPU_AREA
 170         def_bool y
 171
 172 config NEED_PER_CPU_EMBED_FIRST_CHUNK
 173         def_bool y
 174
 175 config NEED_PER_CPU_PAGE_FIRST_CHUNK
 176         def_bool y
 177
 178 config HAVE_CPUMASK_OF_CPU_MAP
 179         def_bool X86_64_SMP
 180
 181 config ARCH_HIBERNATION_POSSIBLE
 182         def_bool y
 183
 184 config ARCH_SUSPEND_POSSIBLE
 185         def_bool y
 186
 187 config ZONE_DMA32
 188         bool
 189         default X86_64
 190
 191 config ARCH_POPULATES_NODE_MAP
 192         def_bool y
 193
 194 config AUDIT_ARCH
 195         bool
 196         default X86_64
 197
 198 config ARCH_SUPPORTS_OPTIMIZED_INLINING
 199         def_bool y
 200
 201 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
 202         def_bool y
 203
 204 config HAVE_INTEL_TXT
 205         def_bool y
 206         depends on EXPERIMENTAL && DMAR && ACPI
 207
 208 config X86_32_SMP
 209         def_bool y
 210         depends on X86_32 && SMP
 211
 212 config X86_64_SMP
 213         def_bool y
 214         depends on X86_64 && SMP
 215
 216 config X86_HT
 217         def_bool y
 218         depends on SMP
 219
 220 config X86_TRAMPOLINE
 221         def_bool y
 222         depends on SMP || (64BIT && ACPI_SLEEP)
 223
 224 config X86_32_LAZY_GS
 225         def_bool y
 226         depends on X86_32 && !CC_STACKPROTECTOR
 227
 228 config ARCH_HWEIGHT_CFLAGS
 229         string
 230         default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
 231         default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64
 232
 233 config KTIME_SCALAR
 234         def_bool X86_32
 235
 236 config ARCH_CPU_PROBE_RELEASE
 237         def_bool y
 238         depends on HOTPLUG_CPU
 239
 240 source "init/Kconfig"
 241 source "kernel/Kconfig.freezer"
 242
 243 menu "Processor type and features"
 244
 245 source "kernel/time/Kconfig"
 246
 247 config SMP
 248         bool "Symmetric multi-processing support"
 249         ---help---
 250           This enables support for systems with more than one CPU. If you have
 251           a system with only one CPU, like most personal computers, say N. If
 252           you have a system with more than one CPU, say Y.
 253
 254           If you say N here, the kernel will run on single and multiprocessor
 255           machines, but will use only one CPU of a multiprocessor machine. If
 256           you say Y here, the kernel will run on many, but not all,
 257           singleprocessor machines. On a singleprocessor machine, the kernel
 258           will run faster if you say N here.
 259
 260           Note that if you say Y here and choose architecture "586" or
 261           "Pentium" under "Processor family", the kernel will not work on 486
 262           architectures. Similarly, multiprocessor kernels for the "PPro"
 263           architecture may not work on all Pentium based boards.
 264
 265           People using multiprocessor machines who say Y here should also say
 266           Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
 267           Management" code will be disabled if you say Y here.
 268
 269           See also <file:Documentation/i386/IO-APIC.txt>,
 270           <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
 271           <http://www.tldp.org/docs.html#howto>.
 272
 273           If you don't know what to do here, say N.
 274
 275 config X86_X2APIC
 276         bool "Support x2apic"
 277         depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
 278         ---help---
 279           This enables x2apic support on CPUs that have this feature.
 280
 281           This allows 32-bit apic IDs (so it can support very large systems),
 282           and accesses the local apic via MSRs not via mmio.
 283
 284           If you don't know what to do here, say N.
 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                 Moorestown MID devices
 318
 319           If you have one of these systems, or if you want to build a
 320           generic distribution kernel, say Y here - otherwise say N.
 321 endif
 322
 323 if X86_64
 324 config X86_EXTENDED_PLATFORM
 325         bool "Support for extended (non-PC) x86 platforms"
 326         default y
 327         ---help---
 328           If you disable this option then the kernel will only support
 329           standard PC platforms. (which covers the vast majority of
 330           systems out there.)
 331
 332           If you enable this option then you'll be able to select support
 333           for the following (non-PC) 64 bit x86 platforms:
 334                 ScaleMP vSMP
 335                 SGI Ultraviolet
 336
 337           If you have one of these systems, or if you want to build a
 338           generic distribution kernel, say Y here - otherwise say N.
 339 endif
 340 # This is an alphabetically sorted list of 64 bit extended platforms
 341 # Please maintain the alphabetic order if and when there are additions
 342
 343 config X86_VSMP
 344         bool "ScaleMP vSMP"
 345         select PARAVIRT_GUEST
 346         select PARAVIRT
 347         depends on X86_64 && PCI
 348         depends on X86_EXTENDED_PLATFORM
 349         ---help---
 350           Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
 351           supposed to run on these EM64T-based machines.  Only choose this option
 352           if you have one of these machines.
 353
 354 config X86_UV
 355         bool "SGI Ultraviolet"
 356         depends on X86_64
 357         depends on X86_EXTENDED_PLATFORM
 358         depends on NUMA
 359         depends on X86_X2APIC
 360         ---help---
 361           This option is needed in order to support SGI Ultraviolet systems.
 362           If you don't have one of these, you should say N here.
 363
 364 # Following is an alphabetically sorted list of 32 bit extended platforms
 365 # Please maintain the alphabetic order if and when there are additions
 366
 367 config X86_ELAN
 368         bool "AMD Elan"
 369         depends on X86_32
 370         depends on X86_EXTENDED_PLATFORM
 371         ---help---
 372           Select this for an AMD Elan processor.
 373
 374           Do not use this option for K6/Athlon/Opteron processors!
 375
 376           If unsure, choose "PC-compatible" instead.
 377
 378 config X86_INTEL_CE
 379         bool "CE4100 TV platform"
 380         depends on PCI
 381         depends on PCI_GODIRECT
 382         depends on X86_32
 383         depends on X86_EXTENDED_PLATFORM
 384         select X86_REBOOTFIXUPS
 385         ---help---
 386           Select for the Intel CE media processor (CE4100) SOC.
 387           This option compiles in support for the CE4100 SOC for settop
 388           boxes and media devices.
 389
 390 config X86_MRST
 391        bool "Moorestown MID platform"
 392         depends on PCI
 393         depends on PCI_GOANY
 394         depends on X86_32
 395         depends on X86_EXTENDED_PLATFORM
 396         depends on X86_IO_APIC
 397         select APB_TIMER
 398         select I2C
 399         select SPI
 400         select INTEL_SCU_IPC
 401         select X86_PLATFORM_DEVICES
 402         ---help---
 403           Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
 404           Internet Device(MID) platform. Moorestown consists of two chips:
 405           Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
 406           Unlike standard x86 PCs, Moorestown does not have many legacy devices
 407           nor standard legacy replacement devices/features. e.g. Moorestown does
 408           not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
 409
 410 config X86_RDC321X
 411         bool "RDC R-321x SoC"
 412         depends on X86_32
 413         depends on X86_EXTENDED_PLATFORM
 414         select M486
 415         select X86_REBOOTFIXUPS
 416         ---help---
 417           This option is needed for RDC R-321x system-on-chip, also known
 418           as R-8610-(G).
 419           If you don't have one of these chips, you should say N here.
 420
 421 config X86_32_NON_STANDARD
 422         bool "Support non-standard 32-bit SMP architectures"
 423         depends on X86_32 && SMP
 424         depends on X86_EXTENDED_PLATFORM
 425         ---help---
 426           This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
 427           subarchitectures.  It is intended for a generic binary kernel.
 428           if you select them all, kernel will probe it one by one. and will
 429           fallback to default.
 430
 431 # Alphabetically sorted list of Non standard 32 bit platforms
 432
 433 config X86_NUMAQ
 434         bool "NUMAQ (IBM/Sequent)"
 435         depends on X86_32_NON_STANDARD
 436         depends on PCI
 437         select NUMA
 438         select X86_MPPARSE
 439         ---help---
 440           This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
 441           NUMA multiquad box. This changes the way that processors are
 442           bootstrapped, and uses Clustered Logical APIC addressing mode instead
 443           of Flat Logical.  You will need a new lynxer.elf file to flash your
 444           firmware with - send email to <Martin.Bligh@us.ibm.com>.
 445
 446 config X86_SUPPORTS_MEMORY_FAILURE
 447         def_bool y
 448         # MCE code calls memory_failure():
 449         depends on X86_MCE
 450         # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
 451         depends on !X86_NUMAQ
 452         # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
 453         depends on X86_64 || !SPARSEMEM
 454         select ARCH_SUPPORTS_MEMORY_FAILURE
 455
 456 config X86_VISWS
 457         bool "SGI 320/540 (Visual Workstation)"
 458         depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
 459         depends on X86_32_NON_STANDARD
 460         ---help---
 461           The SGI Visual Workstation series is an IA32-based workstation
 462           based on SGI systems chips with some legacy PC hardware attached.
 463
 464           Say Y here to create a kernel to run on the SGI 320 or 540.
 465
 466           A kernel compiled for the Visual Workstation will run on general
 467           PCs as well. See <file:Documentation/sgi-visws.txt> for details.
 468
 469 config X86_SUMMIT
 470         bool "Summit/EXA (IBM x440)"
 471         depends on X86_32_NON_STANDARD
 472         ---help---
 473           This option is needed for IBM systems that use the Summit/EXA chipset.
 474           In particular, it is needed for the x440.
 475
 476 config X86_ES7000
 477         bool "Unisys ES7000 IA32 series"
 478         depends on X86_32_NON_STANDARD && X86_BIGSMP
 479         ---help---
 480           Support for Unisys ES7000 systems.  Say 'Y' here if this kernel is
 481           supposed to run on an IA32-based Unisys ES7000 system.
 482
 483 config X86_32_IRIS
 484         tristate "Eurobraille/Iris poweroff module"
 485         depends on X86_32
 486         ---help---
 487           The Iris machines from EuroBraille do not have APM or ACPI support
 488           to shut themselves down properly.  A special I/O sequence is
 489           needed to do so, which is what this module does at
 490           kernel shutdown.
 491
 492           This is only for Iris machines from EuroBraille.
 493
 494           If unused, say N.
 495
 496 config SCHED_OMIT_FRAME_POINTER
 497         def_bool y
 498         prompt "Single-depth WCHAN output"
 499         depends on X86
 500         ---help---
 501           Calculate simpler /proc/<PID>/wchan values. If this option
 502           is disabled then wchan values will recurse back to the
 503           caller function. This provides more accurate wchan values,
 504           at the expense of slightly more scheduling overhead.
 505
 506           If in doubt, say "Y".
 507
 508 menuconfig PARAVIRT_GUEST
 509         bool "Paravirtualized guest support"
 510         ---help---
 511           Say Y here to get to see options related to running Linux under
 512           various hypervisors.  This option alone does not add any kernel code.
 513
 514           If you say N, all options in this submenu will be skipped and disabled.
 515
 516 if PARAVIRT_GUEST
 517
 518 source "arch/x86/xen/Kconfig"
 519
 520 config KVM_CLOCK
 521         bool "KVM paravirtualized clock"
 522         select PARAVIRT
 523         select PARAVIRT_CLOCK
 524         ---help---
 525           Turning on this option will allow you to run a paravirtualized clock
 526           when running over the KVM hypervisor. Instead of relying on a PIT
 527           (or probably other) emulation by the underlying device model, the host
 528           provides the guest with timing infrastructure such as time of day, and
 529           system time
 530
 531 config KVM_GUEST
 532         bool "KVM Guest support"
 533         select PARAVIRT
 534         ---help---
 535           This option enables various optimizations for running under the KVM
 536           hypervisor.
 537
 538 source "arch/x86/lguest/Kconfig"
 539
 540 config PARAVIRT
 541         bool "Enable paravirtualization code"
 542         ---help---
 543           This changes the kernel so it can modify itself when it is run
 544           under a hypervisor, potentially improving performance significantly
 545           over full virtualization.  However, when run without a hypervisor
 546           the kernel is theoretically slower and slightly larger.
 547
 548 config PARAVIRT_SPINLOCKS
 549         bool "Paravirtualization layer for spinlocks"
 550         depends on PARAVIRT && SMP && EXPERIMENTAL
 551         ---help---
 552           Paravirtualized spinlocks allow a pvops backend to replace the
 553           spinlock implementation with something virtualization-friendly
 554           (for example, block the virtual CPU rather than spinning).
 555
 556           Unfortunately the downside is an up to 5% performance hit on
 557           native kernels, with various workloads.
 558
 559           If you are unsure how to answer this question, answer N.
 560
 561 config PARAVIRT_CLOCK
 562         bool
 563
 564 endif
 565
 566 config PARAVIRT_DEBUG
 567         bool "paravirt-ops debugging"
 568         depends on PARAVIRT && DEBUG_KERNEL
 569         ---help---
 570           Enable to debug paravirt_ops internals.  Specifically, BUG if
 571           a paravirt_op is missing when it is called.
 572
 573 config NO_BOOTMEM
 574         def_bool y
 575
 576 config MEMTEST
 577         bool "Memtest"
 578         ---help---
 579           This option adds a kernel parameter 'memtest', which allows memtest
 580           to be set.
 581                 memtest=0, mean disabled; -- default
 582                 memtest=1, mean do 1 test pattern;
 583                 ...
 584                 memtest=4, mean do 4 test patterns.
 585           If you are unsure how to answer this question, answer N.
 586
 587 config X86_SUMMIT_NUMA
 588         def_bool y
 589         depends on X86_32 && NUMA && X86_32_NON_STANDARD
 590
 591 config X86_CYCLONE_TIMER
 592         def_bool y
 593         depends on X86_32_NON_STANDARD
 594
 595 source "arch/x86/Kconfig.cpu"
 596
 597 config HPET_TIMER
 598         def_bool X86_64
 599         prompt "HPET Timer Support" if X86_32
 600         ---help---
 601           Use the IA-PC HPET (High Precision Event Timer) to manage
 602           time in preference to the PIT and RTC, if a HPET is
 603           present.
 604           HPET is the next generation timer replacing legacy 8254s.
 605           The HPET provides a stable time base on SMP
 606           systems, unlike the TSC, but it is more expensive to access,
 607           as it is off-chip.  You can find the HPET spec at
 608           <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
 609
 610           You can safely choose Y here.  However, HPET will only be
 611           activated if the platform and the BIOS support this feature.
 612           Otherwise the 8254 will be used for timing services.
 613
 614           Choose N to continue using the legacy 8254 timer.
 615
 616 config HPET_EMULATE_RTC
 617         def_bool y
 618         depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
 619
 620 config APB_TIMER
 621        def_bool y if MRST
 622        prompt "Langwell APB Timer Support" if X86_MRST
 623        help
 624          APB timer is the replacement for 8254, HPET on X86 MID platforms.
 625          The APBT provides a stable time base on SMP
 626          systems, unlike the TSC, but it is more expensive to access,
 627          as it is off-chip. APB timers are always running regardless of CPU
 628          C states, they are used as per CPU clockevent device when possible.
 629
 630 # Mark as embedded because too many people got it wrong.
 631 # The code disables itself when not needed.
 632 config DMI
 633         default y
 634         bool "Enable DMI scanning" if EMBEDDED
 635         ---help---
 636           Enabled scanning of DMI to identify machine quirks. Say Y
 637           here unless you have verified that your setup is not
 638           affected by entries in the DMI blacklist. Required by PNP
 639           BIOS code.
 640
 641 config GART_IOMMU
 642         bool "GART IOMMU support" if EMBEDDED
 643         default y
 644         select SWIOTLB
 645         depends on X86_64 && PCI && AMD_NB
 646         ---help---
 647           Support for full DMA access of devices with 32bit memory access only
 648           on systems with more than 3GB. This is usually needed for USB,
 649           sound, many IDE/SATA chipsets and some other devices.
 650           Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
 651           based hardware IOMMU and a software bounce buffer based IOMMU used
 652           on Intel systems and as fallback.
 653           The code is only active when needed (enough memory and limited
 654           device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
 655           too.
 656
 657 config CALGARY_IOMMU
 658         bool "IBM Calgary IOMMU support"
 659         select SWIOTLB
 660         depends on X86_64 && PCI && EXPERIMENTAL
 661         ---help---
 662           Support for hardware IOMMUs in IBM's xSeries x366 and x460
 663           systems. Needed to run systems with more than 3GB of memory
 664           properly with 32-bit PCI devices that do not support DAC
 665           (Double Address Cycle). Calgary also supports bus level
 666           isolation, where all DMAs pass through the IOMMU.  This
 667           prevents them from going anywhere except their intended
 668           destination. This catches hard-to-find kernel bugs and
 669           mis-behaving drivers and devices that do not use the DMA-API
 670           properly to set up their DMA buffers.  The IOMMU can be
 671           turned off at boot time with the iommu=off parameter.
 672           Normally the kernel will make the right choice by itself.
 673           If unsure, say Y.
 674
 675 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
 676         def_bool y
 677         prompt "Should Calgary be enabled by default?"
 678         depends on CALGARY_IOMMU
 679         ---help---
 680           Should Calgary be enabled by default? if you choose 'y', Calgary
 681           will be used (if it exists). If you choose 'n', Calgary will not be
 682           used even if it exists. If you choose 'n' and would like to use
 683           Calgary anyway, pass 'iommu=calgary' on the kernel command line.
 684           If unsure, say Y.
 685
 686 config AMD_IOMMU
 687         bool "AMD IOMMU support"
 688         select SWIOTLB
 689         select PCI_MSI
 690         depends on X86_64 && PCI && ACPI
 691         ---help---
 692           With this option you can enable support for AMD IOMMU hardware in
 693           your system. An IOMMU is a hardware component which provides
 694           remapping of DMA memory accesses from devices. With an AMD IOMMU you
 695           can isolate the the DMA memory of different devices and protect the
 696           system from misbehaving device drivers or hardware.
 697
 698           You can find out if your system has an AMD IOMMU if you look into
 699           your BIOS for an option to enable it or if you have an IVRS ACPI
 700           table.
 701
 702 config AMD_IOMMU_STATS
 703         bool "Export AMD IOMMU statistics to debugfs"
 704         depends on AMD_IOMMU
 705         select DEBUG_FS
 706         ---help---
 707           This option enables code in the AMD IOMMU driver to collect various
 708           statistics about whats happening in the driver and exports that
 709           information to userspace via debugfs.
 710           If unsure, say N.
 711
 712 # need this always selected by IOMMU for the VIA workaround
 713 config SWIOTLB
 714         def_bool y if X86_64
 715         ---help---
 716           Support for software bounce buffers used on x86-64 systems
 717           which don't have a hardware IOMMU (e.g. the current generation
 718           of Intel's x86-64 CPUs). Using this PCI devices which can only
 719           access 32-bits of memory can be used on systems with more than
 720           3 GB of memory. If unsure, say Y.
 721
 722 config IOMMU_HELPER
 723         def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
 724
 725 config IOMMU_API
 726         def_bool (AMD_IOMMU || DMAR)
 727
 728 config MAXSMP
 729         bool "Enable Maximum number of SMP Processors and NUMA Nodes"
 730         depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
 731         select CPUMASK_OFFSTACK
 732         ---help---
 733           Enable maximum number of CPUS and NUMA Nodes for this architecture.
 734           If unsure, say N.
 735
 736 config NR_CPUS
 737         int "Maximum number of CPUs" if SMP && !MAXSMP
 738         range 2 8 if SMP && X86_32 && !X86_BIGSMP
 739         range 2 512 if SMP && !MAXSMP
 740         default "1" if !SMP
 741         default "4096" if MAXSMP
 742         default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
 743         default "8" if SMP
 744         ---help---
 745           This allows you to specify the maximum number of CPUs which this
 746           kernel will support.  The maximum supported value is 512 and the
 747           minimum value which makes sense is 2.
 748
 749           This is purely to save memory - each supported CPU adds
 750           approximately eight kilobytes to the kernel image.
 751
 752 config SCHED_SMT
 753         bool "SMT (Hyperthreading) scheduler support"
 754         depends on X86_HT
 755         ---help---
 756           SMT scheduler support improves the CPU scheduler's decision making
 757           when dealing with Intel Pentium 4 chips with HyperThreading at a
 758           cost of slightly increased overhead in some places. If unsure say
 759           N here.
 760
 761 config SCHED_MC
 762         def_bool y
 763         prompt "Multi-core scheduler support"
 764         depends on X86_HT
 765         ---help---
 766           Multi-core scheduler support improves the CPU scheduler's decision
 767           making when dealing with multi-core CPU chips at a cost of slightly
 768           increased overhead in some places. If unsure say N here.
 769
 770 config IRQ_TIME_ACCOUNTING
 771         bool "Fine granularity task level IRQ time accounting"
 772         default n
 773         ---help---
 774           Select this option to enable fine granularity task irq time
 775           accounting. This is done by reading a timestamp on each
 776           transitions between softirq and hardirq state, so there can be a
 777           small performance impact.
 778
 779           If in doubt, say N here.
 780
 781 source "kernel/Kconfig.preempt"
 782
 783 config X86_UP_APIC
 784         bool "Local APIC support on uniprocessors"
 785         depends on X86_32 && !SMP && !X86_32_NON_STANDARD
 786         ---help---
 787           A local APIC (Advanced Programmable Interrupt Controller) is an
 788           integrated interrupt controller in the CPU. If you have a single-CPU
 789           system which has a processor with a local APIC, you can say Y here to
 790           enable and use it. If you say Y here even though your machine doesn't
 791           have a local APIC, then the kernel will still run with no slowdown at
 792           all. The local APIC supports CPU-generated self-interrupts (timer,
 793           performance counters), and the NMI watchdog which detects hard
 794           lockups.
 795
 796 config X86_UP_IOAPIC
 797         bool "IO-APIC support on uniprocessors"
 798         depends on X86_UP_APIC
 799         ---help---
 800           An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
 801           SMP-capable replacement for PC-style interrupt controllers. Most
 802           SMP systems and many recent uniprocessor systems have one.
 803
 804           If you have a single-CPU system with an IO-APIC, you can say Y here
 805           to use it. If you say Y here even though your machine doesn't have
 806           an IO-APIC, then the kernel will still run with no slowdown at all.
 807
 808 config X86_LOCAL_APIC
 809         def_bool y
 810         depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
 811
 812 config X86_IO_APIC
 813         def_bool y
 814         depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
 815
 816 config X86_VISWS_APIC
 817         def_bool y
 818         depends on X86_32 && X86_VISWS
 819
 820 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
 821         bool "Reroute for broken boot IRQs"
 822         depends on X86_IO_APIC
 823         ---help---
 824           This option enables a workaround that fixes a source of
 825           spurious interrupts. This is recommended when threaded
 826           interrupt handling is used on systems where the generation of
 827           superfluous "boot interrupts" cannot be disabled.
 828
 829           Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
 830           entry in the chipset's IO-APIC is masked (as, e.g. the RT
 831           kernel does during interrupt handling). On chipsets where this
 832           boot IRQ generation cannot be disabled, this workaround keeps
 833           the original IRQ line masked so that only the equivalent "boot
 834           IRQ" is delivered to the CPUs. The workaround also tells the
 835           kernel to set up the IRQ handler on the boot IRQ line. In this
 836           way only one interrupt is delivered to the kernel. Otherwise
 837           the spurious second interrupt may cause the kernel to bring
 838           down (vital) interrupt lines.
 839
 840           Only affects "broken" chipsets. Interrupt sharing may be
 841           increased on these systems.
 842
 843 config X86_MCE
 844         bool "Machine Check / overheating reporting"
 845         ---help---
 846           Machine Check support allows the processor to notify the
 847           kernel if it detects a problem (e.g. overheating, data corruption).
 848           The action the kernel takes depends on the severity of the problem,
 849           ranging from warning messages to halting the machine.
 850
 851 config X86_MCE_INTEL
 852         def_bool y
 853         prompt "Intel MCE features"
 854         depends on X86_MCE && X86_LOCAL_APIC
 855         ---help---
 856            Additional support for intel specific MCE features such as
 857            the thermal monitor.
 858
 859 config X86_MCE_AMD
 860         def_bool y
 861         prompt "AMD MCE features"
 862         depends on X86_MCE && X86_LOCAL_APIC
 863         ---help---
 864            Additional support for AMD specific MCE features such as
 865            the DRAM Error Threshold.
 866
 867 config X86_ANCIENT_MCE
 868         bool "Support for old Pentium 5 / WinChip machine checks"
 869         depends on X86_32 && X86_MCE
 870         ---help---
 871           Include support for machine check handling on old Pentium 5 or WinChip
 872           systems. These typically need to be enabled explicitely on the command
 873           line.
 874
 875 config X86_MCE_THRESHOLD
 876         depends on X86_MCE_AMD || X86_MCE_INTEL
 877         def_bool y
 878
 879 config X86_MCE_INJECT
 880         depends on X86_MCE
 881         tristate "Machine check injector support"
 882         ---help---
 883           Provide support for injecting machine checks for testing purposes.
 884           If you don't know what a machine check is and you don't do kernel
 885           QA it is safe to say n.
 886
 887 config X86_THERMAL_VECTOR
 888         def_bool y
 889         depends on X86_MCE_INTEL
 890
 891 config VM86
 892         bool "Enable VM86 support" if EMBEDDED
 893         default y
 894         depends on X86_32
 895         ---help---
 896           This option is required by programs like DOSEMU to run 16-bit legacy
 897           code on X86 processors. It also may be needed by software like
 898           XFree86 to initialize some video cards via BIOS. Disabling this
 899           option saves about 6k.
 900
 901 config TOSHIBA
 902         tristate "Toshiba Laptop support"
 903         depends on X86_32
 904         ---help---
 905           This adds a driver to safely access the System Management Mode of
 906           the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
 907           not work on models with a Phoenix BIOS. The System Management Mode
 908           is used to set the BIOS and power saving options on Toshiba portables.
 909
 910           For information on utilities to make use of this driver see the
 911           Toshiba Linux utilities web site at:
 912           <http://www.buzzard.org.uk/toshiba/>.
 913
 914           Say Y if you intend to run this kernel on a Toshiba portable.
 915           Say N otherwise.
 916
 917 config I8K
 918         tristate "Dell laptop support"
 919         ---help---
 920           This adds a driver to safely access the System Management Mode
 921           of the CPU on the Dell Inspiron 8000. The System Management Mode
 922           is used to read cpu temperature and cooling fan status and to
 923           control the fans on the I8K portables.
 924
 925           This driver has been tested only on the Inspiron 8000 but it may
 926           also work with other Dell laptops. You can force loading on other
 927           models by passing the parameter `force=1' to the module. Use at
 928           your own risk.
 929
 930           For information on utilities to make use of this driver see the
 931           I8K Linux utilities web site at:
 932           <http://people.debian.org/~dz/i8k/>
 933
 934           Say Y if you intend to run this kernel on a Dell Inspiron 8000.
 935           Say N otherwise.
 936
 937 config X86_REBOOTFIXUPS
 938         bool "Enable X86 board specific fixups for reboot"
 939         depends on X86_32
 940         ---help---
 941           This enables chipset and/or board specific fixups to be done
 942           in order to get reboot to work correctly. This is only needed on
 943           some combinations of hardware and BIOS. The symptom, for which
 944           this config is intended, is when reboot ends with a stalled/hung
 945           system.
 946
 947           Currently, the only fixup is for the Geode machines using
 948           CS5530A and CS5536 chipsets and the RDC R-321x SoC.
 949
 950           Say Y if you want to enable the fixup. Currently, it's safe to
 951           enable this option even if you don't need it.
 952           Say N otherwise.
 953
 954 config MICROCODE
 955         tristate "/dev/cpu/microcode - microcode support"
 956         select FW_LOADER
 957         ---help---
 958           If you say Y here, you will be able to update the microcode on
 959           certain Intel and AMD processors. The Intel support is for the
 960           IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
 961           Pentium 4, Xeon etc. The AMD support is for family 0x10 and
 962           0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
 963           You will obviously need the actual microcode binary data itself
 964           which is not shipped with the Linux kernel.
 965
 966           This option selects the general module only, you need to select
 967           at least one vendor specific module as well.
 968
 969           To compile this driver as a module, choose M here: the
 970           module will be called microcode.
 971
 972 config MICROCODE_INTEL
 973         bool "Intel microcode patch loading support"
 974         depends on MICROCODE
 975         default MICROCODE
 976         select FW_LOADER
 977         ---help---
 978           This options enables microcode patch loading support for Intel
 979           processors.
 980
 981           For latest news and information on obtaining all the required
 982           Intel ingredients for this driver, check:
 983           <http://www.urbanmyth.org/microcode/>.
 984
 985 config MICROCODE_AMD
 986         bool "AMD microcode patch loading support"
 987         depends on MICROCODE
 988         select FW_LOADER
 989         ---help---
 990           If you select this option, microcode patch loading support for AMD
 991           processors will be enabled.
 992
 993 config MICROCODE_OLD_INTERFACE
 994         def_bool y
 995         depends on MICROCODE
 996
 997 config X86_MSR
 998         tristate "/dev/cpu/*/msr - Model-specific register support"
 999         ---help---
1000           This device gives privileged processes access to the x86
1001           Model-Specific Registers (MSRs).  It is a character device with
1002           major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1003           MSR accesses are directed to a specific CPU on multi-processor
1004           systems.
1005
1006 config X86_CPUID
1007         tristate "/dev/cpu/*/cpuid - CPU information support"
1008         ---help---
1009           This device gives processes access to the x86 CPUID instruction to
1010           be executed on a specific processor.  It is a character device
1011           with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1012           /dev/cpu/31/cpuid.
1013
1014 choice
1015         prompt "High Memory Support"
1016         default HIGHMEM64G if X86_NUMAQ
1017         default HIGHMEM4G
1018         depends on X86_32
1019
1020 config NOHIGHMEM
1021         bool "off"
1022         depends on !X86_NUMAQ
1023         ---help---
1024           Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1025           However, the address space of 32-bit x86 processors is only 4
1026           Gigabytes large. That means that, if you have a large amount of
1027           physical memory, not all of it can be "permanently mapped" by the
1028           kernel. The physical memory that's not permanently mapped is called
1029           "high memory".
1030
1031           If you are compiling a kernel which will never run on a machine with
1032           more than 1 Gigabyte total physical RAM, answer "off" here (default
1033           choice and suitable for most users). This will result in a "3GB/1GB"
1034           split: 3GB are mapped so that each process sees a 3GB virtual memory
1035           space and the remaining part of the 4GB virtual memory space is used
1036           by the kernel to permanently map as much physical memory as
1037           possible.
1038
1039           If the machine has between 1 and 4 Gigabytes physical RAM, then
1040           answer "4GB" here.
1041
1042           If more than 4 Gigabytes is used then answer "64GB" here. This
1043           selection turns Intel PAE (Physical Address Extension) mode on.
1044           PAE implements 3-level paging on IA32 processors. PAE is fully
1045           supported by Linux, PAE mode is implemented on all recent Intel
1046           processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1047           then the kernel will not boot on CPUs that don't support PAE!
1048
1049           The actual amount of total physical memory will either be
1050           auto detected or can be forced by using a kernel command line option
1051           such as "mem=256M". (Try "man bootparam" or see the documentation of
1052           your boot loader (lilo or loadlin) about how to pass options to the
1053           kernel at boot time.)
1054
1055           If unsure, say "off".
1056
1057 config HIGHMEM4G
1058         bool "4GB"
1059         depends on !X86_NUMAQ
1060         ---help---
1061           Select this if you have a 32-bit processor and between 1 and 4
1062           gigabytes of physical RAM.
1063
1064 config HIGHMEM64G
1065         bool "64GB"
1066         depends on !M386 && !M486
1067         select X86_PAE
1068         ---help---
1069           Select this if you have a 32-bit processor and more than 4
1070           gigabytes of physical RAM.
1071
1072 endchoice
1073
1074 choice
1075         depends on EXPERIMENTAL
1076         prompt "Memory split" if EMBEDDED
1077         default VMSPLIT_3G
1078         depends on X86_32
1079         ---help---
1080           Select the desired split between kernel and user memory.
1081
1082           If the address range available to the kernel is less than the
1083           physical memory installed, the remaining memory will be available
1084           as "high memory". Accessing high memory is a little more costly
1085           than low memory, as it needs to be mapped into the kernel first.
1086           Note that increasing the kernel address space limits the range
1087           available to user programs, making the address space there
1088           tighter.  Selecting anything other than the default 3G/1G split
1089           will also likely make your kernel incompatible with binary-only
1090           kernel modules.
1091
1092           If you are not absolutely sure what you are doing, leave this
1093           option alone!
1094
1095         config VMSPLIT_3G
1096                 bool "3G/1G user/kernel split"
1097         config VMSPLIT_3G_OPT
1098                 depends on !X86_PAE
1099                 bool "3G/1G user/kernel split (for full 1G low memory)"
1100         config VMSPLIT_2G
1101                 bool "2G/2G user/kernel split"
1102         config VMSPLIT_2G_OPT
1103                 depends on !X86_PAE
1104                 bool "2G/2G user/kernel split (for full 2G low memory)"
1105         config VMSPLIT_1G
1106                 bool "1G/3G user/kernel split"
1107 endchoice
1108
1109 config PAGE_OFFSET
1110         hex
1111         default 0xB0000000 if VMSPLIT_3G_OPT
1112         default 0x80000000 if VMSPLIT_2G
1113         default 0x78000000 if VMSPLIT_2G_OPT
1114         default 0x40000000 if VMSPLIT_1G
1115         default 0xC0000000
1116         depends on X86_32
1117
1118 config HIGHMEM
1119         def_bool y
1120         depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1121
1122 config X86_PAE
1123         bool "PAE (Physical Address Extension) Support"
1124         depends on X86_32 && !HIGHMEM4G
1125         ---help---
1126           PAE is required for NX support, and furthermore enables
1127           larger swapspace support for non-overcommit purposes. It
1128           has the cost of more pagetable lookup overhead, and also
1129           consumes more pagetable space per process.
1130
1131 config ARCH_PHYS_ADDR_T_64BIT
1132         def_bool X86_64 || X86_PAE
1133
1134 config ARCH_DMA_ADDR_T_64BIT
1135         def_bool X86_64 || HIGHMEM64G
1136
1137 config DIRECT_GBPAGES
1138         bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
1139         default y
1140         depends on X86_64
1141         ---help---
1142           Allow the kernel linear mapping to use 1GB pages on CPUs that
1143           support it. This can improve the kernel's performance a tiny bit by
1144           reducing TLB pressure. If in doubt, say "Y".
1145
1146 # Common NUMA Features
1147 config NUMA
1148         bool "Numa Memory Allocation and Scheduler Support"
1149         depends on SMP
1150         depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1151         default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1152         ---help---
1153           Enable NUMA (Non Uniform Memory Access) support.
1154
1155           The kernel will try to allocate memory used by a CPU on the
1156           local memory controller of the CPU and add some more
1157           NUMA awareness to the kernel.
1158
1159           For 64-bit this is recommended if the system is Intel Core i7
1160           (or later), AMD Opteron, or EM64T NUMA.
1161
1162           For 32-bit this is only needed on (rare) 32-bit-only platforms
1163           that support NUMA topologies, such as NUMAQ / Summit, or if you
1164           boot a 32-bit kernel on a 64-bit NUMA platform.
1165
1166           Otherwise, you should say N.
1167
1168 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1169         depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1170
1171 config AMD_NUMA
1172         def_bool y
1173         prompt "Old style AMD Opteron NUMA detection"
1174         depends on X86_64 && NUMA && PCI
1175         ---help---
1176           Enable AMD NUMA node topology detection.  You should say Y here if
1177           you have a multi processor AMD system. This uses an old method to
1178           read the NUMA configuration directly from the builtin Northbridge
1179           of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1180           which also takes priority if both are compiled in.
1181
1182 config X86_64_ACPI_NUMA
1183         def_bool y
1184         prompt "ACPI NUMA detection"
1185         depends on X86_64 && NUMA && ACPI && PCI
1186         select ACPI_NUMA
1187         ---help---
1188           Enable ACPI SRAT based node topology detection.
1189
1190 # Some NUMA nodes have memory ranges that span
1191 # other nodes.  Even though a pfn is valid and
1192 # between a node's start and end pfns, it may not
1193 # reside on that node.  See memmap_init_zone()
1194 # for details.
1195 config NODES_SPAN_OTHER_NODES
1196         def_bool y
1197         depends on X86_64_ACPI_NUMA
1198
1199 config NUMA_EMU
1200         bool "NUMA emulation"
1201         depends on X86_64 && NUMA
1202         ---help---
1203           Enable NUMA emulation. A flat machine will be split
1204           into virtual nodes when booted with "numa=fake=N", where N is the
1205           number of nodes. This is only useful for debugging.
1206
1207 config NODES_SHIFT
1208         int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1209         range 1 10
1210         default "10" if MAXSMP
1211         default "6" if X86_64
1212         default "4" if X86_NUMAQ
1213         default "3"
1214         depends on NEED_MULTIPLE_NODES
1215         ---help---
1216           Specify the maximum number of NUMA Nodes available on the target
1217           system.  Increases memory reserved to accommodate various tables.
1218
1219 config HAVE_ARCH_BOOTMEM
1220         def_bool y
1221         depends on X86_32 && NUMA
1222
1223 config ARCH_HAVE_MEMORY_PRESENT
1224         def_bool y
1225         depends on X86_32 && DISCONTIGMEM
1226
1227 config NEED_NODE_MEMMAP_SIZE
1228         def_bool y
1229         depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1230
1231 config HAVE_ARCH_ALLOC_REMAP
1232         def_bool y
1233         depends on X86_32 && NUMA
1234
1235 config ARCH_FLATMEM_ENABLE
1236         def_bool y
1237         depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
1238
1239 config ARCH_DISCONTIGMEM_ENABLE
1240         def_bool y
1241         depends on NUMA && X86_32
1242
1243 config ARCH_DISCONTIGMEM_DEFAULT
1244         def_bool y
1245         depends on NUMA && X86_32
1246
1247 config ARCH_PROC_KCORE_TEXT
1248         def_bool y
1249         depends on X86_64 && PROC_KCORE
1250
1251 config ARCH_SPARSEMEM_DEFAULT
1252         def_bool y
1253         depends on X86_64
1254
1255 config ARCH_SPARSEMEM_ENABLE
1256         def_bool y
1257         depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1258         select SPARSEMEM_STATIC if X86_32
1259         select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1260
1261 config ARCH_SELECT_MEMORY_MODEL
1262         def_bool y
1263         depends on ARCH_SPARSEMEM_ENABLE
1264
1265 config ARCH_MEMORY_PROBE
1266         def_bool X86_64
1267         depends on MEMORY_HOTPLUG
1268
1269 config ILLEGAL_POINTER_VALUE
1270        hex
1271        default 0 if X86_32
1272        default 0xdead000000000000 if X86_64
1273
1274 source "mm/Kconfig"
1275
1276 config HIGHPTE
1277         bool "Allocate 3rd-level pagetables from highmem"
1278         depends on HIGHMEM
1279         ---help---
1280           The VM uses one page table entry for each page of physical memory.
1281           For systems with a lot of RAM, this can be wasteful of precious
1282           low memory.  Setting this option will put user-space page table
1283           entries in high memory.
1284
1285 config X86_CHECK_BIOS_CORRUPTION
1286         bool "Check for low memory corruption"
1287         ---help---
1288           Periodically check for memory corruption in low memory, which
1289           is suspected to be caused by BIOS.  Even when enabled in the
1290           configuration, it is disabled at runtime.  Enable it by
1291           setting "memory_corruption_check=1" on the kernel command
1292           line.  By default it scans the low 64k of memory every 60
1293           seconds; see the memory_corruption_check_size and
1294           memory_corruption_check_period parameters in
1295           Documentation/kernel-parameters.txt to adjust this.
1296
1297           When enabled with the default parameters, this option has
1298           almost no overhead, as it reserves a relatively small amount
1299           of memory and scans it infrequently.  It both detects corruption
1300           and prevents it from affecting the running system.
1301
1302           It is, however, intended as a diagnostic tool; if repeatable
1303           BIOS-originated corruption always affects the same memory,
1304           you can use memmap= to prevent the kernel from using that
1305           memory.
1306
1307 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1308         bool "Set the default setting of memory_corruption_check"
1309         depends on X86_CHECK_BIOS_CORRUPTION
1310         default y
1311         ---help---
1312           Set whether the default state of memory_corruption_check is
1313           on or off.
1314
1315 config X86_RESERVE_LOW
1316         int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1317         default 64
1318         range 4 640
1319         ---help---
1320           Specify the amount of low memory to reserve for the BIOS.
1321
1322           The first page contains BIOS data structures that the kernel
1323           must not use, so that page must always be reserved.
1324
1325           By default we reserve the first 64K of physical RAM, as a
1326           number of BIOSes are known to corrupt that memory range
1327           during events such as suspend/resume or monitor cable
1328           insertion, so it must not be used by the kernel.
1329
1330           You can set this to 4 if you are absolutely sure that you
1331           trust the BIOS to get all its memory reservations and usages
1332           right.  If you know your BIOS have problems beyond the
1333           default 64K area, you can set this to 640 to avoid using the
1334           entire low memory range.
1335
1336           If you have doubts about the BIOS (e.g. suspend/resume does
1337           not work or there's kernel crashes after certain hardware
1338           hotplug events) then you might want to enable
1339           X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1340           typical corruption patterns.
1341
1342           Leave this to the default value of 64 if you are unsure.
1343
1344 config MATH_EMULATION
1345         bool
1346         prompt "Math emulation" if X86_32
1347         ---help---
1348           Linux can emulate a math coprocessor (used for floating point
1349           operations) if you don't have one. 486DX and Pentium processors have
1350           a math coprocessor built in, 486SX and 386 do not, unless you added
1351           a 487DX or 387, respectively. (The messages during boot time can
1352           give you some hints here ["man dmesg"].) Everyone needs either a
1353           coprocessor or this emulation.
1354
1355           If you don't have a math coprocessor, you need to say Y here; if you
1356           say Y here even though you have a coprocessor, the coprocessor will
1357           be used nevertheless. (This behavior can be changed with the kernel
1358           command line option "no387", which comes handy if your coprocessor
1359           is broken. Try "man bootparam" or see the documentation of your boot
1360           loader (lilo or loadlin) about how to pass options to the kernel at
1361           boot time.) This means that it is a good idea to say Y here if you
1362           intend to use this kernel on different machines.
1363
1364           More information about the internals of the Linux math coprocessor
1365           emulation can be found in <file:arch/x86/math-emu/README>.
1366
1367           If you are not sure, say Y; apart from resulting in a 66 KB bigger
1368           kernel, it won't hurt.
1369
1370 config MTRR
1371         def_bool y
1372         prompt "MTRR (Memory Type Range Register) support" if EMBEDDED
1373         ---help---
1374           On Intel P6 family processors (Pentium Pro, Pentium II and later)
1375           the Memory Type Range Registers (MTRRs) may be used to control
1376           processor access to memory ranges. This is most useful if you have
1377           a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1378           allows bus write transfers to be combined into a larger transfer
1379           before bursting over the PCI/AGP bus. This can increase performance
1380           of image write operations 2.5 times or more. Saying Y here creates a
1381           /proc/mtrr file which may be used to manipulate your processor's
1382           MTRRs. Typically the X server should use this.
1383
1384           This code has a reasonably generic interface so that similar
1385           control registers on other processors can be easily supported
1386           as well:
1387
1388           The Cyrix 6x86, 6x86MX and M II processors have Address Range
1389           Registers (ARRs) which provide a similar functionality to MTRRs. For
1390           these, the ARRs are used to emulate the MTRRs.
1391           The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1392           MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1393           write-combining. All of these processors are supported by this code
1394           and it makes sense to say Y here if you have one of them.
1395
1396           Saying Y here also fixes a problem with buggy SMP BIOSes which only
1397           set the MTRRs for the boot CPU and not for the secondary CPUs. This
1398           can lead to all sorts of problems, so it's good to say Y here.
1399
1400           You can safely say Y even if your machine doesn't have MTRRs, you'll
1401           just add about 9 KB to your kernel.
1402
1403           See <file:Documentation/x86/mtrr.txt> for more information.
1404
1405 config MTRR_SANITIZER
1406         def_bool y
1407         prompt "MTRR cleanup support"
1408         depends on MTRR
1409         ---help---
1410           Convert MTRR layout from continuous to discrete, so X drivers can
1411           add writeback entries.
1412
1413           Can be disabled with disable_mtrr_cleanup on the kernel command line.
1414           The largest mtrr entry size for a continuous block can be set with
1415           mtrr_chunk_size.
1416
1417           If unsure, say Y.
1418
1419 config MTRR_SANITIZER_ENABLE_DEFAULT
1420         int "MTRR cleanup enable value (0-1)"
1421         range 0 1
1422         default "0"
1423         depends on MTRR_SANITIZER
1424         ---help---
1425           Enable mtrr cleanup default value
1426
1427 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1428         int "MTRR cleanup spare reg num (0-7)"
1429         range 0 7
1430         default "1"
1431         depends on MTRR_SANITIZER
1432         ---help---
1433           mtrr cleanup spare entries default, it can be changed via
1434           mtrr_spare_reg_nr=N on the kernel command line.
1435
1436 config X86_PAT
1437         def_bool y
1438         prompt "x86 PAT support" if EMBEDDED
1439         depends on MTRR
1440         ---help---
1441           Use PAT attributes to setup page level cache control.
1442
1443           PATs are the modern equivalents of MTRRs and are much more
1444           flexible than MTRRs.
1445
1446           Say N here if you see bootup problems (boot crash, boot hang,
1447           spontaneous reboots) or a non-working video driver.
1448
1449           If unsure, say Y.
1450
1451 config ARCH_USES_PG_UNCACHED
1452         def_bool y
1453         depends on X86_PAT
1454
1455 config EFI
1456         bool "EFI runtime service support"
1457         depends on ACPI
1458         ---help---
1459           This enables the kernel to use EFI runtime services that are
1460           available (such as the EFI variable services).
1461
1462           This option is only useful on systems that have EFI firmware.
1463           In addition, you should use the latest ELILO loader available
1464           at <http://elilo.sourceforge.net> in order to take advantage
1465           of EFI runtime services. However, even with this option, the
1466           resultant kernel should continue to boot on existing non-EFI
1467           platforms.
1468
1469 config SECCOMP
1470         def_bool y
1471         prompt "Enable seccomp to safely compute untrusted bytecode"
1472         ---help---
1473           This kernel feature is useful for number crunching applications
1474           that may need to compute untrusted bytecode during their
1475           execution. By using pipes or other transports made available to
1476           the process as file descriptors supporting the read/write
1477           syscalls, it's possible to isolate those applications in
1478           their own address space using seccomp. Once seccomp is
1479           enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1480           and the task is only allowed to execute a few safe syscalls
1481           defined by each seccomp mode.
1482
1483           If unsure, say Y. Only embedded should say N here.
1484
1485 config CC_STACKPROTECTOR
1486         bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1487         ---help---
1488           This option turns on the -fstack-protector GCC feature. This
1489           feature puts, at the beginning of functions, a canary value on
1490           the stack just before the return address, and validates
1491           the value just before actually returning.  Stack based buffer
1492           overflows (that need to overwrite this return address) now also
1493           overwrite the canary, which gets detected and the attack is then
1494           neutralized via a kernel panic.
1495
1496           This feature requires gcc version 4.2 or above, or a distribution
1497           gcc with the feature backported. Older versions are automatically
1498           detected and for those versions, this configuration option is
1499           ignored. (and a warning is printed during bootup)
1500
1501 source kernel/Kconfig.hz
1502
1503 config KEXEC
1504         bool "kexec system call"
1505         ---help---
1506           kexec is a system call that implements the ability to shutdown your
1507           current kernel, and to start another kernel.  It is like a reboot
1508           but it is independent of the system firmware.   And like a reboot
1509           you can start any kernel with it, not just Linux.
1510
1511           The name comes from the similarity to the exec system call.
1512
1513           It is an ongoing process to be certain the hardware in a machine
1514           is properly shutdown, so do not be surprised if this code does not
1515           initially work for you.  It may help to enable device hotplugging
1516           support.  As of this writing the exact hardware interface is
1517           strongly in flux, so no good recommendation can be made.
1518
1519 config CRASH_DUMP
1520         bool "kernel crash dumps"
1521         depends on X86_64 || (X86_32 && HIGHMEM)
1522         ---help---
1523           Generate crash dump after being started by kexec.
1524           This should be normally only set in special crash dump kernels
1525           which are loaded in the main kernel with kexec-tools into
1526           a specially reserved region and then later executed after
1527           a crash by kdump/kexec. The crash dump kernel must be compiled
1528           to a memory address not used by the main kernel or BIOS using
1529           PHYSICAL_START, or it must be built as a relocatable image
1530           (CONFIG_RELOCATABLE=y).
1531           For more details see Documentation/kdump/kdump.txt
1532
1533 config KEXEC_JUMP
1534         bool "kexec jump (EXPERIMENTAL)"
1535         depends on EXPERIMENTAL
1536         depends on KEXEC && HIBERNATION
1537         ---help---
1538           Jump between original kernel and kexeced kernel and invoke
1539           code in physical address mode via KEXEC
1540
1541 config PHYSICAL_START
1542         hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1543         default "0x1000000"
1544         ---help---
1545           This gives the physical address where the kernel is loaded.
1546
1547           If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1548           bzImage will decompress itself to above physical address and
1549           run from there. Otherwise, bzImage will run from the address where
1550           it has been loaded by the boot loader and will ignore above physical
1551           address.
1552
1553           In normal kdump cases one does not have to set/change this option
1554           as now bzImage can be compiled as a completely relocatable image
1555           (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1556           address. This option is mainly useful for the folks who don't want
1557           to use a bzImage for capturing the crash dump and want to use a
1558           vmlinux instead. vmlinux is not relocatable hence a kernel needs
1559           to be specifically compiled to run from a specific memory area
1560           (normally a reserved region) and this option comes handy.
1561
1562           So if you are using bzImage for capturing the crash dump,
1563           leave the value here unchanged to 0x1000000 and set
1564           CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
1565           for capturing the crash dump change this value to start of
1566           the reserved region.  In other words, it can be set based on
1567           the "X" value as specified in the "crashkernel=YM@XM"
1568           command line boot parameter passed to the panic-ed
1569           kernel. Please take a look at Documentation/kdump/kdump.txt
1570           for more details about crash dumps.
1571
1572           Usage of bzImage for capturing the crash dump is recommended as
1573           one does not have to build two kernels. Same kernel can be used
1574           as production kernel and capture kernel. Above option should have
1575           gone away after relocatable bzImage support is introduced. But it
1576           is present because there are users out there who continue to use
1577           vmlinux for dump capture. This option should go away down the
1578           line.
1579
1580           Don't change this unless you know what you are doing.
1581
1582 config RELOCATABLE
1583         bool "Build a relocatable kernel"
1584         default y
1585         ---help---
1586           This builds a kernel image that retains relocation information
1587           so it can be loaded someplace besides the default 1MB.
1588           The relocations tend to make the kernel binary about 10% larger,
1589           but are discarded at runtime.
1590
1591           One use is for the kexec on panic case where the recovery kernel
1592           must live at a different physical address than the primary
1593           kernel.
1594
1595           Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1596           it has been loaded at and the compile time physical address
1597           (CONFIG_PHYSICAL_START) is ignored.
1598
1599 # Relocation on x86-32 needs some additional build support
1600 config X86_NEED_RELOCS
1601         def_bool y
1602         depends on X86_32 && RELOCATABLE
1603
1604 config PHYSICAL_ALIGN
1605         hex "Alignment value to which kernel should be aligned" if X86_32
1606         default "0x1000000"
1607         range 0x2000 0x1000000
1608         ---help---
1609           This value puts the alignment restrictions on physical address
1610           where kernel is loaded and run from. Kernel is compiled for an
1611           address which meets above alignment restriction.
1612
1613           If bootloader loads the kernel at a non-aligned address and
1614           CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1615           address aligned to above value and run from there.
1616
1617           If bootloader loads the kernel at a non-aligned address and
1618           CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1619           load address and decompress itself to the address it has been
1620           compiled for and run from there. The address for which kernel is
1621           compiled already meets above alignment restrictions. Hence the
1622           end result is that kernel runs from a physical address meeting
1623           above alignment restrictions.
1624
1625           Don't change this unless you know what you are doing.
1626
1627 config HOTPLUG_CPU
1628         bool "Support for hot-pluggable CPUs"
1629         depends on SMP && HOTPLUG
1630         ---help---
1631           Say Y here to allow turning CPUs off and on. CPUs can be
1632           controlled through /sys/devices/system/cpu.
1633           ( Note: power management support will enable this option
1634             automatically on SMP systems. )
1635           Say N if you want to disable CPU hotplug.
1636
1637 config COMPAT_VDSO
1638         def_bool y
1639         prompt "Compat VDSO support"
1640         depends on X86_32 || IA32_EMULATION
1641         ---help---
1642           Map the 32-bit VDSO to the predictable old-style address too.
1643
1644           Say N here if you are running a sufficiently recent glibc
1645           version (2.3.3 or later), to remove the high-mapped
1646           VDSO mapping and to exclusively use the randomized VDSO.
1647
1648           If unsure, say Y.
1649
1650 config CMDLINE_BOOL
1651         bool "Built-in kernel command line"
1652         ---help---
1653           Allow for specifying boot arguments to the kernel at
1654           build time.  On some systems (e.g. embedded ones), it is
1655           necessary or convenient to provide some or all of the
1656           kernel boot arguments with the kernel itself (that is,
1657           to not rely on the boot loader to provide them.)
1658
1659           To compile command line arguments into the kernel,
1660           set this option to 'Y', then fill in the
1661           the boot arguments in CONFIG_CMDLINE.
1662
1663           Systems with fully functional boot loaders (i.e. non-embedded)
1664           should leave this option set to 'N'.
1665
1666 config CMDLINE
1667         string "Built-in kernel command string"
1668         depends on CMDLINE_BOOL
1669         default ""
1670         ---help---
1671           Enter arguments here that should be compiled into the kernel
1672           image and used at boot time.  If the boot loader provides a
1673           command line at boot time, it is appended to this string to
1674           form the full kernel command line, when the system boots.
1675
1676           However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1677           change this behavior.
1678
1679           In most cases, the command line (whether built-in or provided
1680           by the boot loader) should specify the device for the root
1681           file system.
1682
1683 config CMDLINE_OVERRIDE
1684         bool "Built-in command line overrides boot loader arguments"
1685         depends on CMDLINE_BOOL
1686         ---help---
1687           Set this option to 'Y' to have the kernel ignore the boot loader
1688           command line, and use ONLY the built-in command line.
1689
1690           This is used to work around broken boot loaders.  This should
1691           be set to 'N' under normal conditions.
1692
1693 endmenu
1694
1695 config ARCH_ENABLE_MEMORY_HOTPLUG
1696         def_bool y
1697         depends on X86_64 || (X86_32 && HIGHMEM)
1698
1699 config ARCH_ENABLE_MEMORY_HOTREMOVE
1700         def_bool y
1701         depends on MEMORY_HOTPLUG
1702
1703 config HAVE_ARCH_EARLY_PFN_TO_NID
1704         def_bool X86_64
1705         depends on NUMA
1706
1707 config USE_PERCPU_NUMA_NODE_ID
1708         def_bool X86_64
1709         depends on NUMA
1710
1711 menu "Power management and ACPI options"
1712
1713 config ARCH_HIBERNATION_HEADER
1714         def_bool y
1715         depends on X86_64 && HIBERNATION
1716
1717 source "kernel/power/Kconfig"
1718
1719 source "drivers/acpi/Kconfig"
1720
1721 source "drivers/sfi/Kconfig"
1722
1723 config X86_APM_BOOT
1724         def_bool y
1725         depends on APM || APM_MODULE
1726
1727 menuconfig APM
1728         tristate "APM (Advanced Power Management) BIOS support"
1729         depends on X86_32 && PM_SLEEP
1730         ---help---
1731           APM is a BIOS specification for saving power using several different
1732           techniques. This is mostly useful for battery powered laptops with
1733           APM compliant BIOSes. If you say Y here, the system time will be
1734           reset after a RESUME operation, the /proc/apm device will provide
1735           battery status information, and user-space programs will receive
1736           notification of APM "events" (e.g. battery status change).
1737
1738           If you select "Y" here, you can disable actual use of the APM
1739           BIOS by passing the "apm=off" option to the kernel at boot time.
1740
1741           Note that the APM support is almost completely disabled for
1742           machines with more than one CPU.
1743
1744           In order to use APM, you will need supporting software. For location
1745           and more information, read <file:Documentation/power/pm.txt> and the
1746           Battery Powered Linux mini-HOWTO, available from
1747           <http://www.tldp.org/docs.html#howto>.
1748
1749           This driver does not spin down disk drives (see the hdparm(8)
1750           manpage ("man 8 hdparm") for that), and it doesn't turn off
1751           VESA-compliant "green" monitors.
1752
1753           This driver does not support the TI 4000M TravelMate and the ACER
1754           486/DX4/75 because they don't have compliant BIOSes. Many "green"
1755           desktop machines also don't have compliant BIOSes, and this driver
1756           may cause those machines to panic during the boot phase.
1757
1758           Generally, if you don't have a battery in your machine, there isn't
1759           much point in using this driver and you should say N. If you get
1760           random kernel OOPSes or reboots that don't seem to be related to
1761           anything, try disabling/enabling this option (or disabling/enabling
1762           APM in your BIOS).
1763
1764           Some other things you should try when experiencing seemingly random,
1765           "weird" problems:
1766
1767           1) make sure that you have enough swap space and that it is
1768           enabled.
1769           2) pass the "no-hlt" option to the kernel
1770           3) switch on floating point emulation in the kernel and pass
1771           the "no387" option to the kernel
1772           4) pass the "floppy=nodma" option to the kernel
1773           5) pass the "mem=4M" option to the kernel (thereby disabling
1774           all but the first 4 MB of RAM)
1775           6) make sure that the CPU is not over clocked.
1776           7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1777           8) disable the cache from your BIOS settings
1778           9) install a fan for the video card or exchange video RAM
1779           10) install a better fan for the CPU
1780           11) exchange RAM chips
1781           12) exchange the motherboard.
1782
1783           To compile this driver as a module, choose M here: the
1784           module will be called apm.
1785
1786 if APM
1787
1788 config APM_IGNORE_USER_SUSPEND
1789         bool "Ignore USER SUSPEND"
1790         ---help---
1791           This option will ignore USER SUSPEND requests. On machines with a
1792           compliant APM BIOS, you want to say N. However, on the NEC Versa M
1793           series notebooks, it is necessary to say Y because of a BIOS bug.
1794
1795 config APM_DO_ENABLE
1796         bool "Enable PM at boot time"
1797         ---help---
1798           Enable APM features at boot time. From page 36 of the APM BIOS
1799           specification: "When disabled, the APM BIOS does not automatically
1800           power manage devices, enter the Standby State, enter the Suspend
1801           State, or take power saving steps in response to CPU Idle calls."
1802           This driver will make CPU Idle calls when Linux is idle (unless this
1803           feature is turned off -- see "Do CPU IDLE calls", below). This
1804           should always save battery power, but more complicated APM features
1805           will be dependent on your BIOS implementation. You may need to turn
1806           this option off if your computer hangs at boot time when using APM
1807           support, or if it beeps continuously instead of suspending. Turn
1808           this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1809           T400CDT. This is off by default since most machines do fine without
1810           this feature.
1811
1812 config APM_CPU_IDLE
1813         bool "Make CPU Idle calls when idle"
1814         ---help---
1815           Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1816           On some machines, this can activate improved power savings, such as
1817           a slowed CPU clock rate, when the machine is idle. These idle calls
1818           are made after the idle loop has run for some length of time (e.g.,
1819           333 mS). On some machines, this will cause a hang at boot time or
1820           whenever the CPU becomes idle. (On machines with more than one CPU,
1821           this option does nothing.)
1822
1823 config APM_DISPLAY_BLANK
1824         bool "Enable console blanking using APM"
1825         ---help---
1826           Enable console blanking using the APM. Some laptops can use this to
1827           turn off the LCD backlight when the screen blanker of the Linux
1828           virtual console blanks the screen. Note that this is only used by
1829           the virtual console screen blanker, and won't turn off the backlight
1830           when using the X Window system. This also doesn't have anything to
1831           do with your VESA-compliant power-saving monitor. Further, this
1832           option doesn't work for all laptops -- it might not turn off your
1833           backlight at all, or it might print a lot of errors to the console,
1834           especially if you are using gpm.
1835
1836 config APM_ALLOW_INTS
1837         bool "Allow interrupts during APM BIOS calls"
1838         ---help---
1839           Normally we disable external interrupts while we are making calls to
1840           the APM BIOS as a measure to lessen the effects of a badly behaving
1841           BIOS implementation.  The BIOS should reenable interrupts if it
1842           needs to.  Unfortunately, some BIOSes do not -- especially those in
1843           many of the newer IBM Thinkpads.  If you experience hangs when you
1844           suspend, try setting this to Y.  Otherwise, say N.
1845
1846 endif # APM
1847
1848 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1849
1850 source "drivers/cpuidle/Kconfig"
1851
1852 source "drivers/idle/Kconfig"
1853
1854 endmenu
1855
1856
1857 menu "Bus options (PCI etc.)"
1858
1859 config PCI
1860         bool "PCI support"
1861         default y
1862         select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1863         ---help---
1864           Find out whether you have a PCI motherboard. PCI is the name of a
1865           bus system, i.e. the way the CPU talks to the other stuff inside
1866           your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1867           VESA. If you have PCI, say Y, otherwise N.
1868
1869 choice
1870         prompt "PCI access mode"
1871         depends on X86_32 && PCI
1872         default PCI_GOANY
1873         ---help---
1874           On PCI systems, the BIOS can be used to detect the PCI devices and
1875           determine their configuration. However, some old PCI motherboards
1876           have BIOS bugs and may crash if this is done. Also, some embedded
1877           PCI-based systems don't have any BIOS at all. Linux can also try to
1878           detect the PCI hardware directly without using the BIOS.
1879
1880           With this option, you can specify how Linux should detect the
1881           PCI devices. If you choose "BIOS", the BIOS will be used,
1882           if you choose "Direct", the BIOS won't be used, and if you
1883           choose "MMConfig", then PCI Express MMCONFIG will be used.
1884           If you choose "Any", the kernel will try MMCONFIG, then the
1885           direct access method and falls back to the BIOS if that doesn't
1886           work. If unsure, go with the default, which is "Any".
1887
1888 config PCI_GOBIOS
1889         bool "BIOS"
1890
1891 config PCI_GOMMCONFIG
1892         bool "MMConfig"
1893
1894 config PCI_GODIRECT
1895         bool "Direct"
1896
1897 config PCI_GOOLPC
1898         bool "OLPC XO-1"
1899         depends on OLPC
1900
1901 config PCI_GOANY
1902         bool "Any"
1903
1904 endchoice
1905
1906 config PCI_BIOS
1907         def_bool y
1908         depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1909
1910 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1911 config PCI_DIRECT
1912         def_bool y
1913         depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1914
1915 config PCI_MMCONFIG
1916         def_bool y
1917         depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
1918
1919 config PCI_OLPC
1920         def_bool y
1921         depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1922
1923 config PCI_XEN
1924         def_bool y
1925         depends on PCI && XEN
1926         select SWIOTLB_XEN
1927
1928 config PCI_DOMAINS
1929         def_bool y
1930         depends on PCI
1931
1932 config PCI_MMCONFIG
1933         bool "Support mmconfig PCI config space access"
1934         depends on X86_64 && PCI && ACPI
1935
1936 config PCI_CNB20LE_QUIRK
1937         bool "Read CNB20LE Host Bridge Windows" if EMBEDDED
1938         default n
1939         depends on PCI && EXPERIMENTAL
1940         help
1941           Read the PCI windows out of the CNB20LE host bridge. This allows
1942           PCI hotplug to work on systems with the CNB20LE chipset which do
1943           not have ACPI.
1944
1945           There's no public spec for this chipset, and this functionality
1946           is known to be incomplete.
1947
1948           You should say N unless you know you need this.
1949
1950 config DMAR
1951         bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1952         depends on PCI_MSI && ACPI && EXPERIMENTAL
1953         help
1954           DMA remapping (DMAR) devices support enables independent address
1955           translations for Direct Memory Access (DMA) from devices.
1956           These DMA remapping devices are reported via ACPI tables
1957           and include PCI device scope covered by these DMA
1958           remapping devices.
1959
1960 config DMAR_DEFAULT_ON
1961         def_bool y
1962         prompt "Enable DMA Remapping Devices by default"
1963         depends on DMAR
1964         help
1965           Selecting this option will enable a DMAR device at boot time if
1966           one is found. If this option is not selected, DMAR support can
1967           be enabled by passing intel_iommu=on to the kernel. It is
1968           recommended you say N here while the DMAR code remains
1969           experimental.
1970
1971 config DMAR_BROKEN_GFX_WA
1972         bool "Workaround broken graphics drivers (going away soon)"
1973         depends on DMAR && BROKEN
1974         ---help---
1975           Current Graphics drivers tend to use physical address
1976           for DMA and avoid using DMA APIs. Setting this config
1977           option permits the IOMMU driver to set a unity map for
1978           all the OS-visible memory. Hence the driver can continue
1979           to use physical addresses for DMA, at least until this
1980           option is removed in the 2.6.32 kernel.
1981
1982 config DMAR_FLOPPY_WA
1983         def_bool y
1984         depends on DMAR
1985         ---help---
1986           Floppy disk drivers are known to bypass DMA API calls
1987           thereby failing to work when IOMMU is enabled. This
1988           workaround will setup a 1:1 mapping for the first
1989           16MiB to make floppy (an ISA device) work.
1990
1991 config INTR_REMAP
1992         bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1993         depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
1994         ---help---
1995           Supports Interrupt remapping for IO-APIC and MSI devices.
1996           To use x2apic mode in the CPU's which support x2APIC enhancements or
1997           to support platforms with CPU's having > 8 bit APIC ID, say Y.
1998
1999 source "drivers/pci/pcie/Kconfig"
2000
2001 source "drivers/pci/Kconfig"
2002
2003 # x86_64 have no ISA slots, but do have ISA-style DMA.
2004 config ISA_DMA_API
2005         def_bool y
2006
2007 if X86_32
2008
2009 config ISA
2010         bool "ISA support"
2011         ---help---
2012           Find out whether you have ISA slots on your motherboard.  ISA is the
2013           name of a bus system, i.e. the way the CPU talks to the other stuff
2014           inside your box.  Other bus systems are PCI, EISA, MicroChannel
2015           (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
2016           newer boards don't support it.  If you have ISA, say Y, otherwise N.
2017
2018 config EISA
2019         bool "EISA support"
2020         depends on ISA
2021         ---help---
2022           The Extended Industry Standard Architecture (EISA) bus was
2023           developed as an open alternative to the IBM MicroChannel bus.
2024
2025           The EISA bus provided some of the features of the IBM MicroChannel
2026           bus while maintaining backward compatibility with cards made for
2027           the older ISA bus.  The EISA bus saw limited use between 1988 and
2028           1995 when it was made obsolete by the PCI bus.
2029
2030           Say Y here if you are building a kernel for an EISA-based machine.
2031
2032           Otherwise, say N.
2033
2034 source "drivers/eisa/Kconfig"
2035
2036 config MCA
2037         bool "MCA support"
2038         ---help---
2039           MicroChannel Architecture is found in some IBM PS/2 machines and
2040           laptops.  It is a bus system similar to PCI or ISA. See
2041           <file:Documentation/mca.txt> (and especially the web page given
2042           there) before attempting to build an MCA bus kernel.
2043
2044 source "drivers/mca/Kconfig"
2045
2046 config SCx200
2047         tristate "NatSemi SCx200 support"
2048         ---help---
2049           This provides basic support for National Semiconductor's
2050           (now AMD's) Geode processors.  The driver probes for the
2051           PCI-IDs of several on-chip devices, so its a good dependency
2052           for other scx200_* drivers.
2053
2054           If compiled as a module, the driver is named scx200.
2055
2056 config SCx200HR_TIMER
2057         tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2058         depends on SCx200
2059         default y
2060         ---help---
2061           This driver provides a clocksource built upon the on-chip
2062           27MHz high-resolution timer.  Its also a workaround for
2063           NSC Geode SC-1100's buggy TSC, which loses time when the
2064           processor goes idle (as is done by the scheduler).  The
2065           other workaround is idle=poll boot option.
2066
2067 config OLPC
2068         bool "One Laptop Per Child support"
2069         select GPIOLIB
2070         select OLPC_OPENFIRMWARE
2071         ---help---
2072           Add support for detecting the unique features of the OLPC
2073           XO hardware.
2074
2075 config OLPC_XO1
2076         tristate "OLPC XO-1 support"
2077         depends on OLPC && MFD_CS5535
2078         ---help---
2079           Add support for non-essential features of the OLPC XO-1 laptop.
2080
2081 config OLPC_OPENFIRMWARE
2082         bool "Support for OLPC's Open Firmware"
2083         depends on !X86_64 && !X86_PAE
2084         default n
2085         select OF
2086         help
2087           This option adds support for the implementation of Open Firmware
2088           that is used on the OLPC XO-1 Children's Machine.
2089           If unsure, say N here.
2090
2091 config OLPC_OPENFIRMWARE_DT
2092         bool
2093         default y if OLPC_OPENFIRMWARE && PROC_DEVICETREE
2094         select OF_PROMTREE
2095
2096 endif # X86_32
2097
2098 config AMD_NB
2099         def_bool y
2100         depends on CPU_SUP_AMD && PCI
2101
2102 source "drivers/pcmcia/Kconfig"
2103
2104 source "drivers/pci/hotplug/Kconfig"
2105
2106 endmenu
2107
2108
2109 menu "Executable file formats / Emulations"
2110
2111 source "fs/Kconfig.binfmt"
2112
2113 config IA32_EMULATION
2114         bool "IA32 Emulation"
2115         depends on X86_64
2116         select COMPAT_BINFMT_ELF
2117         ---help---
2118           Include code to run 32-bit programs under a 64-bit kernel. You should
2119           likely turn this on, unless you're 100% sure that you don't have any
2120           32-bit programs left.
2121
2122 config IA32_AOUT
2123         tristate "IA32 a.out support"
2124         depends on IA32_EMULATION
2125         ---help---
2126           Support old a.out binaries in the 32bit emulation.
2127
2128 config COMPAT
2129         def_bool y
2130         depends on IA32_EMULATION
2131
2132 config COMPAT_FOR_U64_ALIGNMENT
2133         def_bool COMPAT
2134         depends on X86_64
2135
2136 config SYSVIPC_COMPAT
2137         def_bool y
2138         depends on COMPAT && SYSVIPC
2139
2140 endmenu
2141
2142
2143 config HAVE_ATOMIC_IOMAP
2144         def_bool y
2145         depends on X86_32
2146
2147 config HAVE_TEXT_POKE_SMP
2148         bool
2149         select STOP_MACHINE if SMP
2150
2151 source "net/Kconfig"
2152
2153 source "drivers/Kconfig"
2154
2155 source "drivers/firmware/Kconfig"
2156
2157 source "fs/Kconfig"
2158
2159 source "arch/x86/Kconfig.debug"
2160
2161 source "security/Kconfig"
2162
2163 source "crypto/Kconfig"
2164
2165 source "arch/x86/kvm/Kconfig"
2166
2167 source "lib/Kconfig"