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         select CLKSRC_I8253
  12
  13 config X86_64
  14         def_bool 64BIT
  15
  16 ### Arch settings
  17 config X86
  18         def_bool y
  19         select HAVE_AOUT if X86_32
  20         select HAVE_UNSTABLE_SCHED_CLOCK
  21         select HAVE_IDE
  22         select HAVE_OPROFILE
  23         select HAVE_PERF_EVENTS
  24         select HAVE_IRQ_WORK
  25         select HAVE_IOREMAP_PROT
  26         select HAVE_KPROBES
  27         select HAVE_MEMBLOCK
  28         select ARCH_WANT_OPTIONAL_GPIOLIB
  29         select ARCH_WANT_FRAME_POINTERS
  30         select HAVE_DMA_ATTRS
  31         select HAVE_KRETPROBES
  32         select HAVE_OPTPROBES
  33         select HAVE_FTRACE_MCOUNT_RECORD
  34         select HAVE_C_RECORDMCOUNT
  35         select HAVE_DYNAMIC_FTRACE
  36         select HAVE_FUNCTION_TRACER
  37         select HAVE_FUNCTION_GRAPH_TRACER
  38         select HAVE_FUNCTION_GRAPH_FP_TEST
  39         select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  40         select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
  41         select HAVE_SYSCALL_TRACEPOINTS
  42         select HAVE_KVM
  43         select HAVE_ARCH_KGDB
  44         select HAVE_ARCH_TRACEHOOK
  45         select HAVE_GENERIC_DMA_COHERENT if X86_32
  46         select HAVE_EFFICIENT_UNALIGNED_ACCESS
  47         select USER_STACKTRACE_SUPPORT
  48         select HAVE_REGS_AND_STACK_ACCESS_API
  49         select HAVE_DMA_API_DEBUG
  50         select HAVE_KERNEL_GZIP
  51         select HAVE_KERNEL_BZIP2
  52         select HAVE_KERNEL_LZMA
  53         select HAVE_KERNEL_XZ
  54         select HAVE_KERNEL_LZO
  55         select HAVE_HW_BREAKPOINT
  56         select HAVE_MIXED_BREAKPOINTS_REGS
  57         select PERF_EVENTS
  58         select HAVE_PERF_EVENTS_NMI
  59         select ANON_INODES
  60         select HAVE_ARCH_KMEMCHECK
  61         select HAVE_USER_RETURN_NOTIFIER
  62         select HAVE_ARCH_JUMP_LABEL
  63         select HAVE_TEXT_POKE_SMP
  64         select HAVE_GENERIC_HARDIRQS
  65         select HAVE_SPARSE_IRQ
  66         select GENERIC_FIND_FIRST_BIT
  67         select GENERIC_IRQ_PROBE
  68         select GENERIC_PENDING_IRQ if SMP
  69         select GENERIC_IRQ_SHOW
  70         select IRQ_FORCED_THREADING
  71         select USE_GENERIC_SMP_HELPERS if SMP
  72         select HAVE_BPF_JIT if (X86_64 && NET)
  73
  74 config INSTRUCTION_DECODER
  75         def_bool (KPROBES || PERF_EVENTS)
  76
  77 config OUTPUT_FORMAT
  78         string
  79         default "elf32-i386" if X86_32
  80         default "elf64-x86-64" if X86_64
  81
  82 config ARCH_DEFCONFIG
  83         string
  84         default "arch/x86/configs/i386_defconfig" if X86_32
  85         default "arch/x86/configs/x86_64_defconfig" if X86_64
  86
  87 config GENERIC_CMOS_UPDATE
  88         def_bool y
  89
  90 config CLOCKSOURCE_WATCHDOG
  91         def_bool y
  92
  93 config GENERIC_CLOCKEVENTS
  94         def_bool y
  95
  96 config GENERIC_CLOCKEVENTS_BROADCAST
  97         def_bool y
  98         depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  99
 100 config LOCKDEP_SUPPORT
 101         def_bool y
 102
 103 config STACKTRACE_SUPPORT
 104         def_bool y
 105
 106 config HAVE_LATENCYTOP_SUPPORT
 107         def_bool y
 108
 109 config MMU
 110         def_bool y
 111
 112 config ZONE_DMA
 113         bool "DMA memory allocation support" if EXPERT
 114         default y
 115         help
 116           DMA memory allocation support allows devices with less than 32-bit
 117           addressing to allocate within the first 16MB of address space.
 118           Disable if no such devices will be used.
 119
 120           If unsure, say Y.
 121
 122 config SBUS
 123         bool
 124
 125 config NEED_DMA_MAP_STATE
 126        def_bool (X86_64 || DMAR || DMA_API_DEBUG)
 127
 128 config NEED_SG_DMA_LENGTH
 129         def_bool y
 130
 131 config GENERIC_ISA_DMA
 132         def_bool ISA_DMA_API
 133
 134 config GENERIC_IOMAP
 135         def_bool y
 136
 137 config GENERIC_BUG
 138         def_bool y
 139         depends on BUG
 140         select GENERIC_BUG_RELATIVE_POINTERS if X86_64
 141
 142 config GENERIC_BUG_RELATIVE_POINTERS
 143         bool
 144
 145 config GENERIC_HWEIGHT
 146         def_bool y
 147
 148 config GENERIC_GPIO
 149         bool
 150
 151 config ARCH_MAY_HAVE_PC_FDC
 152         def_bool ISA_DMA_API
 153
 154 config RWSEM_GENERIC_SPINLOCK
 155         def_bool !X86_XADD
 156
 157 config RWSEM_XCHGADD_ALGORITHM
 158         def_bool X86_XADD
 159
 160 config ARCH_HAS_CPU_IDLE_WAIT
 161         def_bool y
 162
 163 config GENERIC_CALIBRATE_DELAY
 164         def_bool y
 165
 166 config GENERIC_TIME_VSYSCALL
 167         bool
 168         default X86_64
 169
 170 config ARCH_HAS_CPU_RELAX
 171         def_bool y
 172
 173 config ARCH_HAS_DEFAULT_IDLE
 174         def_bool y
 175
 176 config ARCH_HAS_CACHE_LINE_SIZE
 177         def_bool y
 178
 179 config HAVE_SETUP_PER_CPU_AREA
 180         def_bool y
 181
 182 config NEED_PER_CPU_EMBED_FIRST_CHUNK
 183         def_bool y
 184
 185 config NEED_PER_CPU_PAGE_FIRST_CHUNK
 186         def_bool y
 187
 188 config HAVE_CPUMASK_OF_CPU_MAP
 189         def_bool X86_64_SMP
 190
 191 config ARCH_HIBERNATION_POSSIBLE
 192         def_bool y
 193
 194 config ARCH_SUSPEND_POSSIBLE
 195         def_bool y
 196
 197 config ZONE_DMA32
 198         bool
 199         default X86_64
 200
 201 config ARCH_POPULATES_NODE_MAP
 202         def_bool y
 203
 204 config AUDIT_ARCH
 205         bool
 206         default X86_64
 207
 208 config ARCH_SUPPORTS_OPTIMIZED_INLINING
 209         def_bool y
 210
 211 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
 212         def_bool y
 213
 214 config HAVE_INTEL_TXT
 215         def_bool y
 216         depends on EXPERIMENTAL && DMAR && ACPI
 217
 218 config X86_32_SMP
 219         def_bool y
 220         depends on X86_32 && SMP
 221
 222 config X86_64_SMP
 223         def_bool y
 224         depends on X86_64 && SMP
 225
 226 config X86_HT
 227         def_bool y
 228         depends on SMP
 229
 230 config X86_32_LAZY_GS
 231         def_bool y
 232         depends on X86_32 && !CC_STACKPROTECTOR
 233
 234 config ARCH_HWEIGHT_CFLAGS
 235         string
 236         default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
 237         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
 238
 239 config KTIME_SCALAR
 240         def_bool X86_32
 241
 242 config ARCH_CPU_PROBE_RELEASE
 243         def_bool y
 244         depends on HOTPLUG_CPU
 245
 246 source "init/Kconfig"
 247 source "kernel/Kconfig.freezer"
 248
 249 menu "Processor type and features"
 250
 251 source "kernel/time/Kconfig"
 252
 253 config SMP
 254         bool "Symmetric multi-processing support"
 255         ---help---
 256           This enables support for systems with more than one CPU. If you have
 257           a system with only one CPU, like most personal computers, say N. If
 258           you have a system with more than one CPU, say Y.
 259
 260           If you say N here, the kernel will run on single and multiprocessor
 261           machines, but will use only one CPU of a multiprocessor machine. If
 262           you say Y here, the kernel will run on many, but not all,
 263           singleprocessor machines. On a singleprocessor machine, the kernel
 264           will run faster if you say N here.
 265
 266           Note that if you say Y here and choose architecture "586" or
 267           "Pentium" under "Processor family", the kernel will not work on 486
 268           architectures. Similarly, multiprocessor kernels for the "PPro"
 269           architecture may not work on all Pentium based boards.
 270
 271           People using multiprocessor machines who say Y here should also say
 272           Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
 273           Management" code will be disabled if you say Y here.
 274
 275           See also <file:Documentation/i386/IO-APIC.txt>,
 276           <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
 277           <http://www.tldp.org/docs.html#howto>.
 278
 279           If you don't know what to do here, say N.
 280
 281 config X86_X2APIC
 282         bool "Support x2apic"
 283         depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
 284         ---help---
 285           This enables x2apic support on CPUs that have this feature.
 286
 287           This allows 32-bit apic IDs (so it can support very large systems),
 288           and accesses the local apic via MSRs not via mmio.
 289
 290           If you don't know what to do here, say N.
 291
 292 config X86_MPPARSE
 293         bool "Enable MPS table" if ACPI
 294         default y
 295         depends on X86_LOCAL_APIC
 296         ---help---
 297           For old smp systems that do not have proper acpi support. Newer systems
 298           (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
 299
 300 config X86_BIGSMP
 301         bool "Support for big SMP systems with more than 8 CPUs"
 302         depends on X86_32 && SMP
 303         ---help---
 304           This option is needed for the systems that have more than 8 CPUs
 305
 306 if X86_32
 307 config X86_EXTENDED_PLATFORM
 308         bool "Support for extended (non-PC) x86 platforms"
 309         default y
 310         ---help---
 311           If you disable this option then the kernel will only support
 312           standard PC platforms. (which covers the vast majority of
 313           systems out there.)
 314
 315           If you enable this option then you'll be able to select support
 316           for the following (non-PC) 32 bit x86 platforms:
 317                 AMD Elan
 318                 NUMAQ (IBM/Sequent)
 319                 RDC R-321x SoC
 320                 SGI 320/540 (Visual Workstation)
 321                 Summit/EXA (IBM x440)
 322                 Unisys ES7000 IA32 series
 323                 Moorestown MID devices
 324
 325           If you have one of these systems, or if you want to build a
 326           generic distribution kernel, say Y here - otherwise say N.
 327 endif
 328
 329 if X86_64
 330 config X86_EXTENDED_PLATFORM
 331         bool "Support for extended (non-PC) x86 platforms"
 332         default y
 333         ---help---
 334           If you disable this option then the kernel will only support
 335           standard PC platforms. (which covers the vast majority of
 336           systems out there.)
 337
 338           If you enable this option then you'll be able to select support
 339           for the following (non-PC) 64 bit x86 platforms:
 340                 ScaleMP vSMP
 341                 SGI Ultraviolet
 342
 343           If you have one of these systems, or if you want to build a
 344           generic distribution kernel, say Y here - otherwise say N.
 345 endif
 346 # This is an alphabetically sorted list of 64 bit extended platforms
 347 # Please maintain the alphabetic order if and when there are additions
 348
 349 config X86_VSMP
 350         bool "ScaleMP vSMP"
 351         select PARAVIRT_GUEST
 352         select PARAVIRT
 353         depends on X86_64 && PCI
 354         depends on X86_EXTENDED_PLATFORM
 355         ---help---
 356           Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
 357           supposed to run on these EM64T-based machines.  Only choose this option
 358           if you have one of these machines.
 359
 360 config X86_UV
 361         bool "SGI Ultraviolet"
 362         depends on X86_64
 363         depends on X86_EXTENDED_PLATFORM
 364         depends on NUMA
 365         depends on X86_X2APIC
 366         ---help---
 367           This option is needed in order to support SGI Ultraviolet systems.
 368           If you don't have one of these, you should say N here.
 369
 370 # Following is an alphabetically sorted list of 32 bit extended platforms
 371 # Please maintain the alphabetic order if and when there are additions
 372
 373 config X86_INTEL_CE
 374         bool "CE4100 TV platform"
 375         depends on PCI
 376         depends on PCI_GODIRECT
 377         depends on X86_32
 378         depends on X86_EXTENDED_PLATFORM
 379         select X86_REBOOTFIXUPS
 380         select OF
 381         select OF_EARLY_FLATTREE
 382         ---help---
 383           Select for the Intel CE media processor (CE4100) SOC.
 384           This option compiles in support for the CE4100 SOC for settop
 385           boxes and media devices.
 386
 387 config X86_MRST
 388        bool "Moorestown MID platform"
 389         depends on PCI
 390         depends on PCI_GOANY
 391         depends on X86_32
 392         depends on X86_EXTENDED_PLATFORM
 393         depends on X86_IO_APIC
 394         select APB_TIMER
 395         select I2C
 396         select SPI
 397         select INTEL_SCU_IPC
 398         select X86_PLATFORM_DEVICES
 399         ---help---
 400           Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
 401           Internet Device(MID) platform. Moorestown consists of two chips:
 402           Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
 403           Unlike standard x86 PCs, Moorestown does not have many legacy devices
 404           nor standard legacy replacement devices/features. e.g. Moorestown does
 405           not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
 406
 407 config X86_RDC321X
 408         bool "RDC R-321x SoC"
 409         depends on X86_32
 410         depends on X86_EXTENDED_PLATFORM
 411         select M486
 412         select X86_REBOOTFIXUPS
 413         ---help---
 414           This option is needed for RDC R-321x system-on-chip, also known
 415           as R-8610-(G).
 416           If you don't have one of these chips, you should say N here.
 417
 418 config X86_32_NON_STANDARD
 419         bool "Support non-standard 32-bit SMP architectures"
 420         depends on X86_32 && SMP
 421         depends on X86_EXTENDED_PLATFORM
 422         ---help---
 423           This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
 424           subarchitectures.  It is intended for a generic binary kernel.
 425           if you select them all, kernel will probe it one by one. and will
 426           fallback to default.
 427
 428 # Alphabetically sorted list of Non standard 32 bit platforms
 429
 430 config X86_NUMAQ
 431         bool "NUMAQ (IBM/Sequent)"
 432         depends on X86_32_NON_STANDARD
 433         depends on PCI
 434         select NUMA
 435         select X86_MPPARSE
 436         ---help---
 437           This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
 438           NUMA multiquad box. This changes the way that processors are
 439           bootstrapped, and uses Clustered Logical APIC addressing mode instead
 440           of Flat Logical.  You will need a new lynxer.elf file to flash your
 441           firmware with - send email to <Martin.Bligh@us.ibm.com>.
 442
 443 config X86_SUPPORTS_MEMORY_FAILURE
 444         def_bool y
 445         # MCE code calls memory_failure():
 446         depends on X86_MCE
 447         # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
 448         depends on !X86_NUMAQ
 449         # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
 450         depends on X86_64 || !SPARSEMEM
 451         select ARCH_SUPPORTS_MEMORY_FAILURE
 452
 453 config X86_VISWS
 454         bool "SGI 320/540 (Visual Workstation)"
 455         depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
 456         depends on X86_32_NON_STANDARD
 457         ---help---
 458           The SGI Visual Workstation series is an IA32-based workstation
 459           based on SGI systems chips with some legacy PC hardware attached.
 460
 461           Say Y here to create a kernel to run on the SGI 320 or 540.
 462
 463           A kernel compiled for the Visual Workstation will run on general
 464           PCs as well. See <file:Documentation/sgi-visws.txt> for details.
 465
 466 config X86_SUMMIT
 467         bool "Summit/EXA (IBM x440)"
 468         depends on X86_32_NON_STANDARD
 469         ---help---
 470           This option is needed for IBM systems that use the Summit/EXA chipset.
 471           In particular, it is needed for the x440.
 472
 473 config X86_ES7000
 474         bool "Unisys ES7000 IA32 series"
 475         depends on X86_32_NON_STANDARD && X86_BIGSMP
 476         ---help---
 477           Support for Unisys ES7000 systems.  Say 'Y' here if this kernel is
 478           supposed to run on an IA32-based Unisys ES7000 system.
 479
 480 config X86_32_IRIS
 481         tristate "Eurobraille/Iris poweroff module"
 482         depends on X86_32
 483         ---help---
 484           The Iris machines from EuroBraille do not have APM or ACPI support
 485           to shut themselves down properly.  A special I/O sequence is
 486           needed to do so, which is what this module does at
 487           kernel shutdown.
 488
 489           This is only for Iris machines from EuroBraille.
 490
 491           If unused, say N.
 492
 493 config SCHED_OMIT_FRAME_POINTER
 494         def_bool y
 495         prompt "Single-depth WCHAN output"
 496         depends on X86
 497         ---help---
 498           Calculate simpler /proc/<PID>/wchan values. If this option
 499           is disabled then wchan values will recurse back to the
 500           caller function. This provides more accurate wchan values,
 501           at the expense of slightly more scheduling overhead.
 502
 503           If in doubt, say "Y".
 504
 505 menuconfig PARAVIRT_GUEST
 506         bool "Paravirtualized guest support"
 507         ---help---
 508           Say Y here to get to see options related to running Linux under
 509           various hypervisors.  This option alone does not add any kernel code.
 510
 511           If you say N, all options in this submenu will be skipped and disabled.
 512
 513 if PARAVIRT_GUEST
 514
 515 source "arch/x86/xen/Kconfig"
 516
 517 config KVM_CLOCK
 518         bool "KVM paravirtualized clock"
 519         select PARAVIRT
 520         select PARAVIRT_CLOCK
 521         ---help---
 522           Turning on this option will allow you to run a paravirtualized clock
 523           when running over the KVM hypervisor. Instead of relying on a PIT
 524           (or probably other) emulation by the underlying device model, the host
 525           provides the guest with timing infrastructure such as time of day, and
 526           system time
 527
 528 config KVM_GUEST
 529         bool "KVM Guest support"
 530         select PARAVIRT
 531         ---help---
 532           This option enables various optimizations for running under the KVM
 533           hypervisor.
 534
 535 source "arch/x86/lguest/Kconfig"
 536
 537 config PARAVIRT
 538         bool "Enable paravirtualization code"
 539         ---help---
 540           This changes the kernel so it can modify itself when it is run
 541           under a hypervisor, potentially improving performance significantly
 542           over full virtualization.  However, when run without a hypervisor
 543           the kernel is theoretically slower and slightly larger.
 544
 545 config PARAVIRT_SPINLOCKS
 546         bool "Paravirtualization layer for spinlocks"
 547         depends on PARAVIRT && SMP && EXPERIMENTAL
 548         ---help---
 549           Paravirtualized spinlocks allow a pvops backend to replace the
 550           spinlock implementation with something virtualization-friendly
 551           (for example, block the virtual CPU rather than spinning).
 552
 553           Unfortunately the downside is an up to 5% performance hit on
 554           native kernels, with various workloads.
 555
 556           If you are unsure how to answer this question, answer N.
 557
 558 config PARAVIRT_CLOCK
 559         bool
 560
 561 endif
 562
 563 config PARAVIRT_DEBUG
 564         bool "paravirt-ops debugging"
 565         depends on PARAVIRT && DEBUG_KERNEL
 566         ---help---
 567           Enable to debug paravirt_ops internals.  Specifically, BUG if
 568           a paravirt_op is missing when it is called.
 569
 570 config NO_BOOTMEM
 571         def_bool y
 572
 573 config MEMTEST
 574         bool "Memtest"
 575         ---help---
 576           This option adds a kernel parameter 'memtest', which allows memtest
 577           to be set.
 578                 memtest=0, mean disabled; -- default
 579                 memtest=1, mean do 1 test pattern;
 580                 ...
 581                 memtest=4, mean do 4 test patterns.
 582           If you are unsure how to answer this question, answer N.
 583
 584 config X86_SUMMIT_NUMA
 585         def_bool y
 586         depends on X86_32 && NUMA && X86_32_NON_STANDARD
 587
 588 config X86_CYCLONE_TIMER
 589         def_bool y
 590         depends on X86_32_NON_STANDARD
 591
 592 source "arch/x86/Kconfig.cpu"
 593
 594 config HPET_TIMER
 595         def_bool X86_64
 596         prompt "HPET Timer Support" if X86_32
 597         ---help---
 598           Use the IA-PC HPET (High Precision Event Timer) to manage
 599           time in preference to the PIT and RTC, if a HPET is
 600           present.
 601           HPET is the next generation timer replacing legacy 8254s.
 602           The HPET provides a stable time base on SMP
 603           systems, unlike the TSC, but it is more expensive to access,
 604           as it is off-chip.  You can find the HPET spec at
 605           <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
 606
 607           You can safely choose Y here.  However, HPET will only be
 608           activated if the platform and the BIOS support this feature.
 609           Otherwise the 8254 will be used for timing services.
 610
 611           Choose N to continue using the legacy 8254 timer.
 612
 613 config HPET_EMULATE_RTC
 614         def_bool y
 615         depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
 616
 617 config APB_TIMER
 618        def_bool y if MRST
 619        prompt "Langwell APB Timer Support" if X86_MRST
 620        help
 621          APB timer is the replacement for 8254, HPET on X86 MID platforms.
 622          The APBT provides a stable time base on SMP
 623          systems, unlike the TSC, but it is more expensive to access,
 624          as it is off-chip. APB timers are always running regardless of CPU
 625          C states, they are used as per CPU clockevent device when possible.
 626
 627 # Mark as expert because too many people got it wrong.
 628 # The code disables itself when not needed.
 629 config DMI
 630         default y
 631         bool "Enable DMI scanning" if EXPERT
 632         ---help---
 633           Enabled scanning of DMI to identify machine quirks. Say Y
 634           here unless you have verified that your setup is not
 635           affected by entries in the DMI blacklist. Required by PNP
 636           BIOS code.
 637
 638 config GART_IOMMU
 639         bool "GART IOMMU support" if EXPERT
 640         default y
 641         select SWIOTLB
 642         depends on X86_64 && PCI && AMD_NB
 643         ---help---
 644           Support for full DMA access of devices with 32bit memory access only
 645           on systems with more than 3GB. This is usually needed for USB,
 646           sound, many IDE/SATA chipsets and some other devices.
 647           Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
 648           based hardware IOMMU and a software bounce buffer based IOMMU used
 649           on Intel systems and as fallback.
 650           The code is only active when needed (enough memory and limited
 651           device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
 652           too.
 653
 654 config CALGARY_IOMMU
 655         bool "IBM Calgary IOMMU support"
 656         select SWIOTLB
 657         depends on X86_64 && PCI && EXPERIMENTAL
 658         ---help---
 659           Support for hardware IOMMUs in IBM's xSeries x366 and x460
 660           systems. Needed to run systems with more than 3GB of memory
 661           properly with 32-bit PCI devices that do not support DAC
 662           (Double Address Cycle). Calgary also supports bus level
 663           isolation, where all DMAs pass through the IOMMU.  This
 664           prevents them from going anywhere except their intended
 665           destination. This catches hard-to-find kernel bugs and
 666           mis-behaving drivers and devices that do not use the DMA-API
 667           properly to set up their DMA buffers.  The IOMMU can be
 668           turned off at boot time with the iommu=off parameter.
 669           Normally the kernel will make the right choice by itself.
 670           If unsure, say Y.
 671
 672 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
 673         def_bool y
 674         prompt "Should Calgary be enabled by default?"
 675         depends on CALGARY_IOMMU
 676         ---help---
 677           Should Calgary be enabled by default? if you choose 'y', Calgary
 678           will be used (if it exists). If you choose 'n', Calgary will not be
 679           used even if it exists. If you choose 'n' and would like to use
 680           Calgary anyway, pass 'iommu=calgary' on the kernel command line.
 681           If unsure, say Y.
 682
 683 # need this always selected by IOMMU for the VIA workaround
 684 config SWIOTLB
 685         def_bool y if X86_64
 686         ---help---
 687           Support for software bounce buffers used on x86-64 systems
 688           which don't have a hardware IOMMU (e.g. the current generation
 689           of Intel's x86-64 CPUs). Using this PCI devices which can only
 690           access 32-bits of memory can be used on systems with more than
 691           3 GB of memory. If unsure, say Y.
 692
 693 config IOMMU_HELPER
 694         def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
 695
 696 config MAXSMP
 697         bool "Enable Maximum number of SMP Processors and NUMA Nodes"
 698         depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
 699         select CPUMASK_OFFSTACK
 700         ---help---
 701           Enable maximum number of CPUS and NUMA Nodes for this architecture.
 702           If unsure, say N.
 703
 704 config NR_CPUS
 705         int "Maximum number of CPUs" if SMP && !MAXSMP
 706         range 2 8 if SMP && X86_32 && !X86_BIGSMP
 707         range 2 512 if SMP && !MAXSMP
 708         default "1" if !SMP
 709         default "4096" if MAXSMP
 710         default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
 711         default "8" if SMP
 712         ---help---
 713           This allows you to specify the maximum number of CPUs which this
 714           kernel will support.  The maximum supported value is 512 and the
 715           minimum value which makes sense is 2.
 716
 717           This is purely to save memory - each supported CPU adds
 718           approximately eight kilobytes to the kernel image.
 719
 720 config SCHED_SMT
 721         bool "SMT (Hyperthreading) scheduler support"
 722         depends on X86_HT
 723         ---help---
 724           SMT scheduler support improves the CPU scheduler's decision making
 725           when dealing with Intel Pentium 4 chips with HyperThreading at a
 726           cost of slightly increased overhead in some places. If unsure say
 727           N here.
 728
 729 config SCHED_MC
 730         def_bool y
 731         prompt "Multi-core scheduler support"
 732         depends on X86_HT
 733         ---help---
 734           Multi-core scheduler support improves the CPU scheduler's decision
 735           making when dealing with multi-core CPU chips at a cost of slightly
 736           increased overhead in some places. If unsure say N here.
 737
 738 config IRQ_TIME_ACCOUNTING
 739         bool "Fine granularity task level IRQ time accounting"
 740         default n
 741         ---help---
 742           Select this option to enable fine granularity task irq time
 743           accounting. This is done by reading a timestamp on each
 744           transitions between softirq and hardirq state, so there can be a
 745           small performance impact.
 746
 747           If in doubt, say N here.
 748
 749 source "kernel/Kconfig.preempt"
 750
 751 config X86_UP_APIC
 752         bool "Local APIC support on uniprocessors"
 753         depends on X86_32 && !SMP && !X86_32_NON_STANDARD
 754         ---help---
 755           A local APIC (Advanced Programmable Interrupt Controller) is an
 756           integrated interrupt controller in the CPU. If you have a single-CPU
 757           system which has a processor with a local APIC, you can say Y here to
 758           enable and use it. If you say Y here even though your machine doesn't
 759           have a local APIC, then the kernel will still run with no slowdown at
 760           all. The local APIC supports CPU-generated self-interrupts (timer,
 761           performance counters), and the NMI watchdog which detects hard
 762           lockups.
 763
 764 config X86_UP_IOAPIC
 765         bool "IO-APIC support on uniprocessors"
 766         depends on X86_UP_APIC
 767         ---help---
 768           An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
 769           SMP-capable replacement for PC-style interrupt controllers. Most
 770           SMP systems and many recent uniprocessor systems have one.
 771
 772           If you have a single-CPU system with an IO-APIC, you can say Y here
 773           to use it. If you say Y here even though your machine doesn't have
 774           an IO-APIC, then the kernel will still run with no slowdown at all.
 775
 776 config X86_LOCAL_APIC
 777         def_bool y
 778         depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
 779
 780 config X86_IO_APIC
 781         def_bool y
 782         depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC
 783
 784 config X86_VISWS_APIC
 785         def_bool y
 786         depends on X86_32 && X86_VISWS
 787
 788 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
 789         bool "Reroute for broken boot IRQs"
 790         depends on X86_IO_APIC
 791         ---help---
 792           This option enables a workaround that fixes a source of
 793           spurious interrupts. This is recommended when threaded
 794           interrupt handling is used on systems where the generation of
 795           superfluous "boot interrupts" cannot be disabled.
 796
 797           Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
 798           entry in the chipset's IO-APIC is masked (as, e.g. the RT
 799           kernel does during interrupt handling). On chipsets where this
 800           boot IRQ generation cannot be disabled, this workaround keeps
 801           the original IRQ line masked so that only the equivalent "boot
 802           IRQ" is delivered to the CPUs. The workaround also tells the
 803           kernel to set up the IRQ handler on the boot IRQ line. In this
 804           way only one interrupt is delivered to the kernel. Otherwise
 805           the spurious second interrupt may cause the kernel to bring
 806           down (vital) interrupt lines.
 807
 808           Only affects "broken" chipsets. Interrupt sharing may be
 809           increased on these systems.
 810
 811 config X86_MCE
 812         bool "Machine Check / overheating reporting"
 813         ---help---
 814           Machine Check support allows the processor to notify the
 815           kernel if it detects a problem (e.g. overheating, data corruption).
 816           The action the kernel takes depends on the severity of the problem,
 817           ranging from warning messages to halting the machine.
 818
 819 config X86_MCE_INTEL
 820         def_bool y
 821         prompt "Intel MCE features"
 822         depends on X86_MCE && X86_LOCAL_APIC
 823         ---help---
 824            Additional support for intel specific MCE features such as
 825            the thermal monitor.
 826
 827 config X86_MCE_AMD
 828         def_bool y
 829         prompt "AMD MCE features"
 830         depends on X86_MCE && X86_LOCAL_APIC
 831         ---help---
 832            Additional support for AMD specific MCE features such as
 833            the DRAM Error Threshold.
 834
 835 config X86_ANCIENT_MCE
 836         bool "Support for old Pentium 5 / WinChip machine checks"
 837         depends on X86_32 && X86_MCE
 838         ---help---
 839           Include support for machine check handling on old Pentium 5 or WinChip
 840           systems. These typically need to be enabled explicitely on the command
 841           line.
 842
 843 config X86_MCE_THRESHOLD
 844         depends on X86_MCE_AMD || X86_MCE_INTEL
 845         def_bool y
 846
 847 config X86_MCE_INJECT
 848         depends on X86_MCE
 849         tristate "Machine check injector support"
 850         ---help---
 851           Provide support for injecting machine checks for testing purposes.
 852           If you don't know what a machine check is and you don't do kernel
 853           QA it is safe to say n.
 854
 855 config X86_THERMAL_VECTOR
 856         def_bool y
 857         depends on X86_MCE_INTEL
 858
 859 config VM86
 860         bool "Enable VM86 support" if EXPERT
 861         default y
 862         depends on X86_32
 863         ---help---
 864           This option is required by programs like DOSEMU to run 16-bit legacy
 865           code on X86 processors. It also may be needed by software like
 866           XFree86 to initialize some video cards via BIOS. Disabling this
 867           option saves about 6k.
 868
 869 config TOSHIBA
 870         tristate "Toshiba Laptop support"
 871         depends on X86_32
 872         ---help---
 873           This adds a driver to safely access the System Management Mode of
 874           the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
 875           not work on models with a Phoenix BIOS. The System Management Mode
 876           is used to set the BIOS and power saving options on Toshiba portables.
 877
 878           For information on utilities to make use of this driver see the
 879           Toshiba Linux utilities web site at:
 880           <http://www.buzzard.org.uk/toshiba/>.
 881
 882           Say Y if you intend to run this kernel on a Toshiba portable.
 883           Say N otherwise.
 884
 885 config I8K
 886         tristate "Dell laptop support"
 887         select HWMON
 888         ---help---
 889           This adds a driver to safely access the System Management Mode
 890           of the CPU on the Dell Inspiron 8000. The System Management Mode
 891           is used to read cpu temperature and cooling fan status and to
 892           control the fans on the I8K portables.
 893
 894           This driver has been tested only on the Inspiron 8000 but it may
 895           also work with other Dell laptops. You can force loading on other
 896           models by passing the parameter `force=1' to the module. Use at
 897           your own risk.
 898
 899           For information on utilities to make use of this driver see the
 900           I8K Linux utilities web site at:
 901           <http://people.debian.org/~dz/i8k/>
 902
 903           Say Y if you intend to run this kernel on a Dell Inspiron 8000.
 904           Say N otherwise.
 905
 906 config X86_REBOOTFIXUPS
 907         bool "Enable X86 board specific fixups for reboot"
 908         depends on X86_32
 909         ---help---
 910           This enables chipset and/or board specific fixups to be done
 911           in order to get reboot to work correctly. This is only needed on
 912           some combinations of hardware and BIOS. The symptom, for which
 913           this config is intended, is when reboot ends with a stalled/hung
 914           system.
 915
 916           Currently, the only fixup is for the Geode machines using
 917           CS5530A and CS5536 chipsets and the RDC R-321x SoC.
 918
 919           Say Y if you want to enable the fixup. Currently, it's safe to
 920           enable this option even if you don't need it.
 921           Say N otherwise.
 922
 923 config MICROCODE
 924         tristate "/dev/cpu/microcode - microcode support"
 925         select FW_LOADER
 926         ---help---
 927           If you say Y here, you will be able to update the microcode on
 928           certain Intel and AMD processors. The Intel support is for the
 929           IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
 930           Pentium 4, Xeon etc. The AMD support is for family 0x10 and
 931           0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
 932           You will obviously need the actual microcode binary data itself
 933           which is not shipped with the Linux kernel.
 934
 935           This option selects the general module only, you need to select
 936           at least one vendor specific module as well.
 937
 938           To compile this driver as a module, choose M here: the
 939           module will be called microcode.
 940
 941 config MICROCODE_INTEL
 942         bool "Intel microcode patch loading support"
 943         depends on MICROCODE
 944         default MICROCODE
 945         select FW_LOADER
 946         ---help---
 947           This options enables microcode patch loading support for Intel
 948           processors.
 949
 950           For latest news and information on obtaining all the required
 951           Intel ingredients for this driver, check:
 952           <http://www.urbanmyth.org/microcode/>.
 953
 954 config MICROCODE_AMD
 955         bool "AMD microcode patch loading support"
 956         depends on MICROCODE
 957         select FW_LOADER
 958         ---help---
 959           If you select this option, microcode patch loading support for AMD
 960           processors will be enabled.
 961
 962 config MICROCODE_OLD_INTERFACE
 963         def_bool y
 964         depends on MICROCODE
 965
 966 config X86_MSR
 967         tristate "/dev/cpu/*/msr - Model-specific register support"
 968         ---help---
 969           This device gives privileged processes access to the x86
 970           Model-Specific Registers (MSRs).  It is a character device with
 971           major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
 972           MSR accesses are directed to a specific CPU on multi-processor
 973           systems.
 974
 975 config X86_CPUID
 976         tristate "/dev/cpu/*/cpuid - CPU information support"
 977         ---help---
 978           This device gives processes access to the x86 CPUID instruction to
 979           be executed on a specific processor.  It is a character device
 980           with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
 981           /dev/cpu/31/cpuid.
 982
 983 choice
 984         prompt "High Memory Support"
 985         default HIGHMEM64G if X86_NUMAQ
 986         default HIGHMEM4G
 987         depends on X86_32
 988
 989 config NOHIGHMEM
 990         bool "off"
 991         depends on !X86_NUMAQ
 992         ---help---
 993           Linux can use up to 64 Gigabytes of physical memory on x86 systems.
 994           However, the address space of 32-bit x86 processors is only 4
 995           Gigabytes large. That means that, if you have a large amount of
 996           physical memory, not all of it can be "permanently mapped" by the
 997           kernel. The physical memory that's not permanently mapped is called
 998           "high memory".
 999
1000           If you are compiling a kernel which will never run on a machine with
1001           more than 1 Gigabyte total physical RAM, answer "off" here (default
1002           choice and suitable for most users). This will result in a "3GB/1GB"
1003           split: 3GB are mapped so that each process sees a 3GB virtual memory
1004           space and the remaining part of the 4GB virtual memory space is used
1005           by the kernel to permanently map as much physical memory as
1006           possible.
1007
1008           If the machine has between 1 and 4 Gigabytes physical RAM, then
1009           answer "4GB" here.
1010
1011           If more than 4 Gigabytes is used then answer "64GB" here. This
1012           selection turns Intel PAE (Physical Address Extension) mode on.
1013           PAE implements 3-level paging on IA32 processors. PAE is fully
1014           supported by Linux, PAE mode is implemented on all recent Intel
1015           processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1016           then the kernel will not boot on CPUs that don't support PAE!
1017
1018           The actual amount of total physical memory will either be
1019           auto detected or can be forced by using a kernel command line option
1020           such as "mem=256M". (Try "man bootparam" or see the documentation of
1021           your boot loader (lilo or loadlin) about how to pass options to the
1022           kernel at boot time.)
1023
1024           If unsure, say "off".
1025
1026 config HIGHMEM4G
1027         bool "4GB"
1028         depends on !X86_NUMAQ
1029         ---help---
1030           Select this if you have a 32-bit processor and between 1 and 4
1031           gigabytes of physical RAM.
1032
1033 config HIGHMEM64G
1034         bool "64GB"
1035         depends on !M386 && !M486
1036         select X86_PAE
1037         ---help---
1038           Select this if you have a 32-bit processor and more than 4
1039           gigabytes of physical RAM.
1040
1041 endchoice
1042
1043 choice
1044         depends on EXPERIMENTAL
1045         prompt "Memory split" if EXPERT
1046         default VMSPLIT_3G
1047         depends on X86_32
1048         ---help---
1049           Select the desired split between kernel and user memory.
1050
1051           If the address range available to the kernel is less than the
1052           physical memory installed, the remaining memory will be available
1053           as "high memory". Accessing high memory is a little more costly
1054           than low memory, as it needs to be mapped into the kernel first.
1055           Note that increasing the kernel address space limits the range
1056           available to user programs, making the address space there
1057           tighter.  Selecting anything other than the default 3G/1G split
1058           will also likely make your kernel incompatible with binary-only
1059           kernel modules.
1060
1061           If you are not absolutely sure what you are doing, leave this
1062           option alone!
1063
1064         config VMSPLIT_3G
1065                 bool "3G/1G user/kernel split"
1066         config VMSPLIT_3G_OPT
1067                 depends on !X86_PAE
1068                 bool "3G/1G user/kernel split (for full 1G low memory)"
1069         config VMSPLIT_2G
1070                 bool "2G/2G user/kernel split"
1071         config VMSPLIT_2G_OPT
1072                 depends on !X86_PAE
1073                 bool "2G/2G user/kernel split (for full 2G low memory)"
1074         config VMSPLIT_1G
1075                 bool "1G/3G user/kernel split"
1076 endchoice
1077
1078 config PAGE_OFFSET
1079         hex
1080         default 0xB0000000 if VMSPLIT_3G_OPT
1081         default 0x80000000 if VMSPLIT_2G
1082         default 0x78000000 if VMSPLIT_2G_OPT
1083         default 0x40000000 if VMSPLIT_1G
1084         default 0xC0000000
1085         depends on X86_32
1086
1087 config HIGHMEM
1088         def_bool y
1089         depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1090
1091 config X86_PAE
1092         bool "PAE (Physical Address Extension) Support"
1093         depends on X86_32 && !HIGHMEM4G
1094         ---help---
1095           PAE is required for NX support, and furthermore enables
1096           larger swapspace support for non-overcommit purposes. It
1097           has the cost of more pagetable lookup overhead, and also
1098           consumes more pagetable space per process.
1099
1100 config ARCH_PHYS_ADDR_T_64BIT
1101         def_bool X86_64 || X86_PAE
1102
1103 config ARCH_DMA_ADDR_T_64BIT
1104         def_bool X86_64 || HIGHMEM64G
1105
1106 config DIRECT_GBPAGES
1107         bool "Enable 1GB pages for kernel pagetables" if EXPERT
1108         default y
1109         depends on X86_64
1110         ---help---
1111           Allow the kernel linear mapping to use 1GB pages on CPUs that
1112           support it. This can improve the kernel's performance a tiny bit by
1113           reducing TLB pressure. If in doubt, say "Y".
1114
1115 # Common NUMA Features
1116 config NUMA
1117         bool "Numa Memory Allocation and Scheduler Support"
1118         depends on SMP
1119         depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1120         default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1121         ---help---
1122           Enable NUMA (Non Uniform Memory Access) support.
1123
1124           The kernel will try to allocate memory used by a CPU on the
1125           local memory controller of the CPU and add some more
1126           NUMA awareness to the kernel.
1127
1128           For 64-bit this is recommended if the system is Intel Core i7
1129           (or later), AMD Opteron, or EM64T NUMA.
1130
1131           For 32-bit this is only needed on (rare) 32-bit-only platforms
1132           that support NUMA topologies, such as NUMAQ / Summit, or if you
1133           boot a 32-bit kernel on a 64-bit NUMA platform.
1134
1135           Otherwise, you should say N.
1136
1137 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1138         depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1139
1140 config AMD_NUMA
1141         def_bool y
1142         prompt "Old style AMD Opteron NUMA detection"
1143         depends on NUMA && PCI
1144         ---help---
1145           Enable AMD NUMA node topology detection.  You should say Y here if
1146           you have a multi processor AMD system. This uses an old method to
1147           read the NUMA configuration directly from the builtin Northbridge
1148           of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1149           which also takes priority if both are compiled in.
1150
1151 config X86_64_ACPI_NUMA
1152         def_bool y
1153         prompt "ACPI NUMA detection"
1154         depends on X86_64 && NUMA && ACPI && PCI
1155         select ACPI_NUMA
1156         ---help---
1157           Enable ACPI SRAT based node topology detection.
1158
1159 # Some NUMA nodes have memory ranges that span
1160 # other nodes.  Even though a pfn is valid and
1161 # between a node's start and end pfns, it may not
1162 # reside on that node.  See memmap_init_zone()
1163 # for details.
1164 config NODES_SPAN_OTHER_NODES
1165         def_bool y
1166         depends on X86_64_ACPI_NUMA
1167
1168 config NUMA_EMU
1169         bool "NUMA emulation"
1170         depends on NUMA
1171         ---help---
1172           Enable NUMA emulation. A flat machine will be split
1173           into virtual nodes when booted with "numa=fake=N", where N is the
1174           number of nodes. This is only useful for debugging.
1175
1176 config NODES_SHIFT
1177         int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1178         range 1 10
1179         default "10" if MAXSMP
1180         default "6" if X86_64
1181         default "4" if X86_NUMAQ
1182         default "3"
1183         depends on NEED_MULTIPLE_NODES
1184         ---help---
1185           Specify the maximum number of NUMA Nodes available on the target
1186           system.  Increases memory reserved to accommodate various tables.
1187
1188 config HAVE_ARCH_BOOTMEM
1189         def_bool y
1190         depends on X86_32 && NUMA
1191
1192 config HAVE_ARCH_ALLOC_REMAP
1193         def_bool y
1194         depends on X86_32 && NUMA
1195
1196 config ARCH_HAVE_MEMORY_PRESENT
1197         def_bool y
1198         depends on X86_32 && DISCONTIGMEM
1199
1200 config NEED_NODE_MEMMAP_SIZE
1201         def_bool y
1202         depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1203
1204 config ARCH_FLATMEM_ENABLE
1205         def_bool y
1206         depends on X86_32 && !NUMA
1207
1208 config ARCH_DISCONTIGMEM_ENABLE
1209         def_bool y
1210         depends on NUMA && X86_32
1211
1212 config ARCH_DISCONTIGMEM_DEFAULT
1213         def_bool y
1214         depends on NUMA && X86_32
1215
1216 config ARCH_SPARSEMEM_ENABLE
1217         def_bool y
1218         depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1219         select SPARSEMEM_STATIC if X86_32
1220         select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1221
1222 config ARCH_SPARSEMEM_DEFAULT
1223         def_bool y
1224         depends on X86_64
1225
1226 config ARCH_SELECT_MEMORY_MODEL
1227         def_bool y
1228         depends on ARCH_SPARSEMEM_ENABLE
1229
1230 config ARCH_MEMORY_PROBE
1231         def_bool X86_64
1232         depends on MEMORY_HOTPLUG
1233
1234 config ARCH_PROC_KCORE_TEXT
1235         def_bool y
1236         depends on X86_64 && PROC_KCORE
1237
1238 config ILLEGAL_POINTER_VALUE
1239        hex
1240        default 0 if X86_32
1241        default 0xdead000000000000 if X86_64
1242
1243 source "mm/Kconfig"
1244
1245 config HIGHPTE
1246         bool "Allocate 3rd-level pagetables from highmem"
1247         depends on HIGHMEM
1248         ---help---
1249           The VM uses one page table entry for each page of physical memory.
1250           For systems with a lot of RAM, this can be wasteful of precious
1251           low memory.  Setting this option will put user-space page table
1252           entries in high memory.
1253
1254 config X86_CHECK_BIOS_CORRUPTION
1255         bool "Check for low memory corruption"
1256         ---help---
1257           Periodically check for memory corruption in low memory, which
1258           is suspected to be caused by BIOS.  Even when enabled in the
1259           configuration, it is disabled at runtime.  Enable it by
1260           setting "memory_corruption_check=1" on the kernel command
1261           line.  By default it scans the low 64k of memory every 60
1262           seconds; see the memory_corruption_check_size and
1263           memory_corruption_check_period parameters in
1264           Documentation/kernel-parameters.txt to adjust this.
1265
1266           When enabled with the default parameters, this option has
1267           almost no overhead, as it reserves a relatively small amount
1268           of memory and scans it infrequently.  It both detects corruption
1269           and prevents it from affecting the running system.
1270
1271           It is, however, intended as a diagnostic tool; if repeatable
1272           BIOS-originated corruption always affects the same memory,
1273           you can use memmap= to prevent the kernel from using that
1274           memory.
1275
1276 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1277         bool "Set the default setting of memory_corruption_check"
1278         depends on X86_CHECK_BIOS_CORRUPTION
1279         default y
1280         ---help---
1281           Set whether the default state of memory_corruption_check is
1282           on or off.
1283
1284 config X86_RESERVE_LOW
1285         int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1286         default 64
1287         range 4 640
1288         ---help---
1289           Specify the amount of low memory to reserve for the BIOS.
1290
1291           The first page contains BIOS data structures that the kernel
1292           must not use, so that page must always be reserved.
1293
1294           By default we reserve the first 64K of physical RAM, as a
1295           number of BIOSes are known to corrupt that memory range
1296           during events such as suspend/resume or monitor cable
1297           insertion, so it must not be used by the kernel.
1298
1299           You can set this to 4 if you are absolutely sure that you
1300           trust the BIOS to get all its memory reservations and usages
1301           right.  If you know your BIOS have problems beyond the
1302           default 64K area, you can set this to 640 to avoid using the
1303           entire low memory range.
1304
1305           If you have doubts about the BIOS (e.g. suspend/resume does
1306           not work or there's kernel crashes after certain hardware
1307           hotplug events) then you might want to enable
1308           X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1309           typical corruption patterns.
1310
1311           Leave this to the default value of 64 if you are unsure.
1312
1313 config MATH_EMULATION
1314         bool
1315         prompt "Math emulation" if X86_32
1316         ---help---
1317           Linux can emulate a math coprocessor (used for floating point
1318           operations) if you don't have one. 486DX and Pentium processors have
1319           a math coprocessor built in, 486SX and 386 do not, unless you added
1320           a 487DX or 387, respectively. (The messages during boot time can
1321           give you some hints here ["man dmesg"].) Everyone needs either a
1322           coprocessor or this emulation.
1323
1324           If you don't have a math coprocessor, you need to say Y here; if you
1325           say Y here even though you have a coprocessor, the coprocessor will
1326           be used nevertheless. (This behavior can be changed with the kernel
1327           command line option "no387", which comes handy if your coprocessor
1328           is broken. Try "man bootparam" or see the documentation of your boot
1329           loader (lilo or loadlin) about how to pass options to the kernel at
1330           boot time.) This means that it is a good idea to say Y here if you
1331           intend to use this kernel on different machines.
1332
1333           More information about the internals of the Linux math coprocessor
1334           emulation can be found in <file:arch/x86/math-emu/README>.
1335
1336           If you are not sure, say Y; apart from resulting in a 66 KB bigger
1337           kernel, it won't hurt.
1338
1339 config MTRR
1340         def_bool y
1341         prompt "MTRR (Memory Type Range Register) support" if EXPERT
1342         ---help---
1343           On Intel P6 family processors (Pentium Pro, Pentium II and later)
1344           the Memory Type Range Registers (MTRRs) may be used to control
1345           processor access to memory ranges. This is most useful if you have
1346           a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1347           allows bus write transfers to be combined into a larger transfer
1348           before bursting over the PCI/AGP bus. This can increase performance
1349           of image write operations 2.5 times or more. Saying Y here creates a
1350           /proc/mtrr file which may be used to manipulate your processor's
1351           MTRRs. Typically the X server should use this.
1352
1353           This code has a reasonably generic interface so that similar
1354           control registers on other processors can be easily supported
1355           as well:
1356
1357           The Cyrix 6x86, 6x86MX and M II processors have Address Range
1358           Registers (ARRs) which provide a similar functionality to MTRRs. For
1359           these, the ARRs are used to emulate the MTRRs.
1360           The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1361           MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1362           write-combining. All of these processors are supported by this code
1363           and it makes sense to say Y here if you have one of them.
1364
1365           Saying Y here also fixes a problem with buggy SMP BIOSes which only
1366           set the MTRRs for the boot CPU and not for the secondary CPUs. This
1367           can lead to all sorts of problems, so it's good to say Y here.
1368
1369           You can safely say Y even if your machine doesn't have MTRRs, you'll
1370           just add about 9 KB to your kernel.
1371
1372           See <file:Documentation/x86/mtrr.txt> for more information.
1373
1374 config MTRR_SANITIZER
1375         def_bool y
1376         prompt "MTRR cleanup support"
1377         depends on MTRR
1378         ---help---
1379           Convert MTRR layout from continuous to discrete, so X drivers can
1380           add writeback entries.
1381
1382           Can be disabled with disable_mtrr_cleanup on the kernel command line.
1383           The largest mtrr entry size for a continuous block can be set with
1384           mtrr_chunk_size.
1385
1386           If unsure, say Y.
1387
1388 config MTRR_SANITIZER_ENABLE_DEFAULT
1389         int "MTRR cleanup enable value (0-1)"
1390         range 0 1
1391         default "0"
1392         depends on MTRR_SANITIZER
1393         ---help---
1394           Enable mtrr cleanup default value
1395
1396 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1397         int "MTRR cleanup spare reg num (0-7)"
1398         range 0 7
1399         default "1"
1400         depends on MTRR_SANITIZER
1401         ---help---
1402           mtrr cleanup spare entries default, it can be changed via
1403           mtrr_spare_reg_nr=N on the kernel command line.
1404
1405 config X86_PAT
1406         def_bool y
1407         prompt "x86 PAT support" if EXPERT
1408         depends on MTRR
1409         ---help---
1410           Use PAT attributes to setup page level cache control.
1411
1412           PATs are the modern equivalents of MTRRs and are much more
1413           flexible than MTRRs.
1414
1415           Say N here if you see bootup problems (boot crash, boot hang,
1416           spontaneous reboots) or a non-working video driver.
1417
1418           If unsure, say Y.
1419
1420 config ARCH_USES_PG_UNCACHED
1421         def_bool y
1422         depends on X86_PAT
1423
1424 config EFI
1425         bool "EFI runtime service support"
1426         depends on ACPI
1427         ---help---
1428           This enables the kernel to use EFI runtime services that are
1429           available (such as the EFI variable services).
1430
1431           This option is only useful on systems that have EFI firmware.
1432           In addition, you should use the latest ELILO loader available
1433           at <http://elilo.sourceforge.net> in order to take advantage
1434           of EFI runtime services. However, even with this option, the
1435           resultant kernel should continue to boot on existing non-EFI
1436           platforms.
1437
1438 config SECCOMP
1439         def_bool y
1440         prompt "Enable seccomp to safely compute untrusted bytecode"
1441         ---help---
1442           This kernel feature is useful for number crunching applications
1443           that may need to compute untrusted bytecode during their
1444           execution. By using pipes or other transports made available to
1445           the process as file descriptors supporting the read/write
1446           syscalls, it's possible to isolate those applications in
1447           their own address space using seccomp. Once seccomp is
1448           enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1449           and the task is only allowed to execute a few safe syscalls
1450           defined by each seccomp mode.
1451
1452           If unsure, say Y. Only embedded should say N here.
1453
1454 config CC_STACKPROTECTOR
1455         bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1456         ---help---
1457           This option turns on the -fstack-protector GCC feature. This
1458           feature puts, at the beginning of functions, a canary value on
1459           the stack just before the return address, and validates
1460           the value just before actually returning.  Stack based buffer
1461           overflows (that need to overwrite this return address) now also
1462           overwrite the canary, which gets detected and the attack is then
1463           neutralized via a kernel panic.
1464
1465           This feature requires gcc version 4.2 or above, or a distribution
1466           gcc with the feature backported. Older versions are automatically
1467           detected and for those versions, this configuration option is
1468           ignored. (and a warning is printed during bootup)
1469
1470 source kernel/Kconfig.hz
1471
1472 config KEXEC
1473         bool "kexec system call"
1474         ---help---
1475           kexec is a system call that implements the ability to shutdown your
1476           current kernel, and to start another kernel.  It is like a reboot
1477           but it is independent of the system firmware.   And like a reboot
1478           you can start any kernel with it, not just Linux.
1479
1480           The name comes from the similarity to the exec system call.
1481
1482           It is an ongoing process to be certain the hardware in a machine
1483           is properly shutdown, so do not be surprised if this code does not
1484           initially work for you.  It may help to enable device hotplugging
1485           support.  As of this writing the exact hardware interface is
1486           strongly in flux, so no good recommendation can be made.
1487
1488 config CRASH_DUMP
1489         bool "kernel crash dumps"
1490         depends on X86_64 || (X86_32 && HIGHMEM)
1491         ---help---
1492           Generate crash dump after being started by kexec.
1493           This should be normally only set in special crash dump kernels
1494           which are loaded in the main kernel with kexec-tools into
1495           a specially reserved region and then later executed after
1496           a crash by kdump/kexec. The crash dump kernel must be compiled
1497           to a memory address not used by the main kernel or BIOS using
1498           PHYSICAL_START, or it must be built as a relocatable image
1499           (CONFIG_RELOCATABLE=y).
1500           For more details see Documentation/kdump/kdump.txt
1501
1502 config KEXEC_JUMP
1503         bool "kexec jump (EXPERIMENTAL)"
1504         depends on EXPERIMENTAL
1505         depends on KEXEC && HIBERNATION
1506         ---help---
1507           Jump between original kernel and kexeced kernel and invoke
1508           code in physical address mode via KEXEC
1509
1510 config PHYSICAL_START
1511         hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1512         default "0x1000000"
1513         ---help---
1514           This gives the physical address where the kernel is loaded.
1515
1516           If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1517           bzImage will decompress itself to above physical address and
1518           run from there. Otherwise, bzImage will run from the address where
1519           it has been loaded by the boot loader and will ignore above physical
1520           address.
1521
1522           In normal kdump cases one does not have to set/change this option
1523           as now bzImage can be compiled as a completely relocatable image
1524           (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1525           address. This option is mainly useful for the folks who don't want
1526           to use a bzImage for capturing the crash dump and want to use a
1527           vmlinux instead. vmlinux is not relocatable hence a kernel needs
1528           to be specifically compiled to run from a specific memory area
1529           (normally a reserved region) and this option comes handy.
1530
1531           So if you are using bzImage for capturing the crash dump,
1532           leave the value here unchanged to 0x1000000 and set
1533           CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
1534           for capturing the crash dump change this value to start of
1535           the reserved region.  In other words, it can be set based on
1536           the "X" value as specified in the "crashkernel=YM@XM"
1537           command line boot parameter passed to the panic-ed
1538           kernel. Please take a look at Documentation/kdump/kdump.txt
1539           for more details about crash dumps.
1540
1541           Usage of bzImage for capturing the crash dump is recommended as
1542           one does not have to build two kernels. Same kernel can be used
1543           as production kernel and capture kernel. Above option should have
1544           gone away after relocatable bzImage support is introduced. But it
1545           is present because there are users out there who continue to use
1546           vmlinux for dump capture. This option should go away down the
1547           line.
1548
1549           Don't change this unless you know what you are doing.
1550
1551 config RELOCATABLE
1552         bool "Build a relocatable kernel"
1553         default y
1554         ---help---
1555           This builds a kernel image that retains relocation information
1556           so it can be loaded someplace besides the default 1MB.
1557           The relocations tend to make the kernel binary about 10% larger,
1558           but are discarded at runtime.
1559
1560           One use is for the kexec on panic case where the recovery kernel
1561           must live at a different physical address than the primary
1562           kernel.
1563
1564           Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1565           it has been loaded at and the compile time physical address
1566           (CONFIG_PHYSICAL_START) is ignored.
1567
1568 # Relocation on x86-32 needs some additional build support
1569 config X86_NEED_RELOCS
1570         def_bool y
1571         depends on X86_32 && RELOCATABLE
1572
1573 config PHYSICAL_ALIGN
1574         hex "Alignment value to which kernel should be aligned" if X86_32
1575         default "0x1000000"
1576         range 0x2000 0x1000000
1577         ---help---
1578           This value puts the alignment restrictions on physical address
1579           where kernel is loaded and run from. Kernel is compiled for an
1580           address which meets above alignment restriction.
1581
1582           If bootloader loads the kernel at a non-aligned address and
1583           CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1584           address aligned to above value and run from there.
1585
1586           If bootloader loads the kernel at a non-aligned address and
1587           CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1588           load address and decompress itself to the address it has been
1589           compiled for and run from there. The address for which kernel is
1590           compiled already meets above alignment restrictions. Hence the
1591           end result is that kernel runs from a physical address meeting
1592           above alignment restrictions.
1593
1594           Don't change this unless you know what you are doing.
1595
1596 config HOTPLUG_CPU
1597         bool "Support for hot-pluggable CPUs"
1598         depends on SMP && HOTPLUG
1599         ---help---
1600           Say Y here to allow turning CPUs off and on. CPUs can be
1601           controlled through /sys/devices/system/cpu.
1602           ( Note: power management support will enable this option
1603             automatically on SMP systems. )
1604           Say N if you want to disable CPU hotplug.
1605
1606 config COMPAT_VDSO
1607         def_bool y
1608         prompt "Compat VDSO support"
1609         depends on X86_32 || IA32_EMULATION
1610         ---help---
1611           Map the 32-bit VDSO to the predictable old-style address too.
1612
1613           Say N here if you are running a sufficiently recent glibc
1614           version (2.3.3 or later), to remove the high-mapped
1615           VDSO mapping and to exclusively use the randomized VDSO.
1616
1617           If unsure, say Y.
1618
1619 config CMDLINE_BOOL
1620         bool "Built-in kernel command line"
1621         ---help---
1622           Allow for specifying boot arguments to the kernel at
1623           build time.  On some systems (e.g. embedded ones), it is
1624           necessary or convenient to provide some or all of the
1625           kernel boot arguments with the kernel itself (that is,
1626           to not rely on the boot loader to provide them.)
1627
1628           To compile command line arguments into the kernel,
1629           set this option to 'Y', then fill in the
1630           the boot arguments in CONFIG_CMDLINE.
1631
1632           Systems with fully functional boot loaders (i.e. non-embedded)
1633           should leave this option set to 'N'.
1634
1635 config CMDLINE
1636         string "Built-in kernel command string"
1637         depends on CMDLINE_BOOL
1638         default ""
1639         ---help---
1640           Enter arguments here that should be compiled into the kernel
1641           image and used at boot time.  If the boot loader provides a
1642           command line at boot time, it is appended to this string to
1643           form the full kernel command line, when the system boots.
1644
1645           However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1646           change this behavior.
1647
1648           In most cases, the command line (whether built-in or provided
1649           by the boot loader) should specify the device for the root
1650           file system.
1651
1652 config CMDLINE_OVERRIDE
1653         bool "Built-in command line overrides boot loader arguments"
1654         depends on CMDLINE_BOOL
1655         ---help---
1656           Set this option to 'Y' to have the kernel ignore the boot loader
1657           command line, and use ONLY the built-in command line.
1658
1659           This is used to work around broken boot loaders.  This should
1660           be set to 'N' under normal conditions.
1661
1662 endmenu
1663
1664 config ARCH_ENABLE_MEMORY_HOTPLUG
1665         def_bool y
1666         depends on X86_64 || (X86_32 && HIGHMEM)
1667
1668 config ARCH_ENABLE_MEMORY_HOTREMOVE
1669         def_bool y
1670         depends on MEMORY_HOTPLUG
1671
1672 config USE_PERCPU_NUMA_NODE_ID
1673         def_bool y
1674         depends on NUMA
1675
1676 menu "Power management and ACPI options"
1677
1678 config ARCH_HIBERNATION_HEADER
1679         def_bool y
1680         depends on X86_64 && HIBERNATION
1681
1682 source "kernel/power/Kconfig"
1683
1684 source "drivers/acpi/Kconfig"
1685
1686 source "drivers/sfi/Kconfig"
1687
1688 config X86_APM_BOOT
1689         def_bool y
1690         depends on APM || APM_MODULE
1691
1692 menuconfig APM
1693         tristate "APM (Advanced Power Management) BIOS support"
1694         depends on X86_32 && PM_SLEEP
1695         ---help---
1696           APM is a BIOS specification for saving power using several different
1697           techniques. This is mostly useful for battery powered laptops with
1698           APM compliant BIOSes. If you say Y here, the system time will be
1699           reset after a RESUME operation, the /proc/apm device will provide
1700           battery status information, and user-space programs will receive
1701           notification of APM "events" (e.g. battery status change).
1702
1703           If you select "Y" here, you can disable actual use of the APM
1704           BIOS by passing the "apm=off" option to the kernel at boot time.
1705
1706           Note that the APM support is almost completely disabled for
1707           machines with more than one CPU.
1708
1709           In order to use APM, you will need supporting software. For location
1710           and more information, read <file:Documentation/power/pm.txt> and the
1711           Battery Powered Linux mini-HOWTO, available from
1712           <http://www.tldp.org/docs.html#howto>.
1713
1714           This driver does not spin down disk drives (see the hdparm(8)
1715           manpage ("man 8 hdparm") for that), and it doesn't turn off
1716           VESA-compliant "green" monitors.
1717
1718           This driver does not support the TI 4000M TravelMate and the ACER
1719           486/DX4/75 because they don't have compliant BIOSes. Many "green"
1720           desktop machines also don't have compliant BIOSes, and this driver
1721           may cause those machines to panic during the boot phase.
1722
1723           Generally, if you don't have a battery in your machine, there isn't
1724           much point in using this driver and you should say N. If you get
1725           random kernel OOPSes or reboots that don't seem to be related to
1726           anything, try disabling/enabling this option (or disabling/enabling
1727           APM in your BIOS).
1728
1729           Some other things you should try when experiencing seemingly random,
1730           "weird" problems:
1731
1732           1) make sure that you have enough swap space and that it is
1733           enabled.
1734           2) pass the "no-hlt" option to the kernel
1735           3) switch on floating point emulation in the kernel and pass
1736           the "no387" option to the kernel
1737           4) pass the "floppy=nodma" option to the kernel
1738           5) pass the "mem=4M" option to the kernel (thereby disabling
1739           all but the first 4 MB of RAM)
1740           6) make sure that the CPU is not over clocked.
1741           7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1742           8) disable the cache from your BIOS settings
1743           9) install a fan for the video card or exchange video RAM
1744           10) install a better fan for the CPU
1745           11) exchange RAM chips
1746           12) exchange the motherboard.
1747
1748           To compile this driver as a module, choose M here: the
1749           module will be called apm.
1750
1751 if APM
1752
1753 config APM_IGNORE_USER_SUSPEND
1754         bool "Ignore USER SUSPEND"
1755         ---help---
1756           This option will ignore USER SUSPEND requests. On machines with a
1757           compliant APM BIOS, you want to say N. However, on the NEC Versa M
1758           series notebooks, it is necessary to say Y because of a BIOS bug.
1759
1760 config APM_DO_ENABLE
1761         bool "Enable PM at boot time"
1762         ---help---
1763           Enable APM features at boot time. From page 36 of the APM BIOS
1764           specification: "When disabled, the APM BIOS does not automatically
1765           power manage devices, enter the Standby State, enter the Suspend
1766           State, or take power saving steps in response to CPU Idle calls."
1767           This driver will make CPU Idle calls when Linux is idle (unless this
1768           feature is turned off -- see "Do CPU IDLE calls", below). This
1769           should always save battery power, but more complicated APM features
1770           will be dependent on your BIOS implementation. You may need to turn
1771           this option off if your computer hangs at boot time when using APM
1772           support, or if it beeps continuously instead of suspending. Turn
1773           this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1774           T400CDT. This is off by default since most machines do fine without
1775           this feature.
1776
1777 config APM_CPU_IDLE
1778         bool "Make CPU Idle calls when idle"
1779         ---help---
1780           Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1781           On some machines, this can activate improved power savings, such as
1782           a slowed CPU clock rate, when the machine is idle. These idle calls
1783           are made after the idle loop has run for some length of time (e.g.,
1784           333 mS). On some machines, this will cause a hang at boot time or
1785           whenever the CPU becomes idle. (On machines with more than one CPU,
1786           this option does nothing.)
1787
1788 config APM_DISPLAY_BLANK
1789         bool "Enable console blanking using APM"
1790         ---help---
1791           Enable console blanking using the APM. Some laptops can use this to
1792           turn off the LCD backlight when the screen blanker of the Linux
1793           virtual console blanks the screen. Note that this is only used by
1794           the virtual console screen blanker, and won't turn off the backlight
1795           when using the X Window system. This also doesn't have anything to
1796           do with your VESA-compliant power-saving monitor. Further, this
1797           option doesn't work for all laptops -- it might not turn off your
1798           backlight at all, or it might print a lot of errors to the console,
1799           especially if you are using gpm.
1800
1801 config APM_ALLOW_INTS
1802         bool "Allow interrupts during APM BIOS calls"
1803         ---help---
1804           Normally we disable external interrupts while we are making calls to
1805           the APM BIOS as a measure to lessen the effects of a badly behaving
1806           BIOS implementation.  The BIOS should reenable interrupts if it
1807           needs to.  Unfortunately, some BIOSes do not -- especially those in
1808           many of the newer IBM Thinkpads.  If you experience hangs when you
1809           suspend, try setting this to Y.  Otherwise, say N.
1810
1811 endif # APM
1812
1813 source "drivers/cpufreq/Kconfig"
1814
1815 source "drivers/cpuidle/Kconfig"
1816
1817 source "drivers/idle/Kconfig"
1818
1819 endmenu
1820
1821
1822 menu "Bus options (PCI etc.)"
1823
1824 config PCI
1825         bool "PCI support"
1826         default y
1827         select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1828         ---help---
1829           Find out whether you have a PCI motherboard. PCI is the name of a
1830           bus system, i.e. the way the CPU talks to the other stuff inside
1831           your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1832           VESA. If you have PCI, say Y, otherwise N.
1833
1834 choice
1835         prompt "PCI access mode"
1836         depends on X86_32 && PCI
1837         default PCI_GOANY
1838         ---help---
1839           On PCI systems, the BIOS can be used to detect the PCI devices and
1840           determine their configuration. However, some old PCI motherboards
1841           have BIOS bugs and may crash if this is done. Also, some embedded
1842           PCI-based systems don't have any BIOS at all. Linux can also try to
1843           detect the PCI hardware directly without using the BIOS.
1844
1845           With this option, you can specify how Linux should detect the
1846           PCI devices. If you choose "BIOS", the BIOS will be used,
1847           if you choose "Direct", the BIOS won't be used, and if you
1848           choose "MMConfig", then PCI Express MMCONFIG will be used.
1849           If you choose "Any", the kernel will try MMCONFIG, then the
1850           direct access method and falls back to the BIOS if that doesn't
1851           work. If unsure, go with the default, which is "Any".
1852
1853 config PCI_GOBIOS
1854         bool "BIOS"
1855
1856 config PCI_GOMMCONFIG
1857         bool "MMConfig"
1858
1859 config PCI_GODIRECT
1860         bool "Direct"
1861
1862 config PCI_GOOLPC
1863         bool "OLPC XO-1"
1864         depends on OLPC
1865
1866 config PCI_GOANY
1867         bool "Any"
1868
1869 endchoice
1870
1871 config PCI_BIOS
1872         def_bool y
1873         depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1874
1875 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1876 config PCI_DIRECT
1877         def_bool y
1878         depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1879
1880 config PCI_MMCONFIG
1881         def_bool y
1882         depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
1883
1884 config PCI_OLPC
1885         def_bool y
1886         depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1887
1888 config PCI_XEN
1889         def_bool y
1890         depends on PCI && XEN
1891         select SWIOTLB_XEN
1892
1893 config PCI_DOMAINS
1894         def_bool y
1895         depends on PCI
1896
1897 config PCI_MMCONFIG
1898         bool "Support mmconfig PCI config space access"
1899         depends on X86_64 && PCI && ACPI
1900
1901 config PCI_CNB20LE_QUIRK
1902         bool "Read CNB20LE Host Bridge Windows" if EXPERT
1903         default n
1904         depends on PCI && EXPERIMENTAL
1905         help
1906           Read the PCI windows out of the CNB20LE host bridge. This allows
1907           PCI hotplug to work on systems with the CNB20LE chipset which do
1908           not have ACPI.
1909
1910           There's no public spec for this chipset, and this functionality
1911           is known to be incomplete.
1912
1913           You should say N unless you know you need this.
1914
1915 source "drivers/pci/pcie/Kconfig"
1916
1917 source "drivers/pci/Kconfig"
1918
1919 # x86_64 have no ISA slots, but can have ISA-style DMA.
1920 config ISA_DMA_API
1921         bool "ISA-style DMA support" if (X86_64 && EXPERT)
1922         default y
1923         help
1924           Enables ISA-style DMA support for devices requiring such controllers.
1925           If unsure, say Y.
1926
1927 if X86_32
1928
1929 config ISA
1930         bool "ISA support"
1931         ---help---
1932           Find out whether you have ISA slots on your motherboard.  ISA is the
1933           name of a bus system, i.e. the way the CPU talks to the other stuff
1934           inside your box.  Other bus systems are PCI, EISA, MicroChannel
1935           (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
1936           newer boards don't support it.  If you have ISA, say Y, otherwise N.
1937
1938 config EISA
1939         bool "EISA support"
1940         depends on ISA
1941         ---help---
1942           The Extended Industry Standard Architecture (EISA) bus was
1943           developed as an open alternative to the IBM MicroChannel bus.
1944
1945           The EISA bus provided some of the features of the IBM MicroChannel
1946           bus while maintaining backward compatibility with cards made for
1947           the older ISA bus.  The EISA bus saw limited use between 1988 and
1948           1995 when it was made obsolete by the PCI bus.
1949
1950           Say Y here if you are building a kernel for an EISA-based machine.
1951
1952           Otherwise, say N.
1953
1954 source "drivers/eisa/Kconfig"
1955
1956 config MCA
1957         bool "MCA support"
1958         ---help---
1959           MicroChannel Architecture is found in some IBM PS/2 machines and
1960           laptops.  It is a bus system similar to PCI or ISA. See
1961           <file:Documentation/mca.txt> (and especially the web page given
1962           there) before attempting to build an MCA bus kernel.
1963
1964 source "drivers/mca/Kconfig"
1965
1966 config SCx200
1967         tristate "NatSemi SCx200 support"
1968         ---help---
1969           This provides basic support for National Semiconductor's
1970           (now AMD's) Geode processors.  The driver probes for the
1971           PCI-IDs of several on-chip devices, so its a good dependency
1972           for other scx200_* drivers.
1973
1974           If compiled as a module, the driver is named scx200.
1975
1976 config SCx200HR_TIMER
1977         tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1978         depends on SCx200
1979         default y
1980         ---help---
1981           This driver provides a clocksource built upon the on-chip
1982           27MHz high-resolution timer.  Its also a workaround for
1983           NSC Geode SC-1100's buggy TSC, which loses time when the
1984           processor goes idle (as is done by the scheduler).  The
1985           other workaround is idle=poll boot option.
1986
1987 config OLPC
1988         bool "One Laptop Per Child support"
1989         depends on !X86_PAE
1990         select GPIOLIB
1991         select OF
1992         select OF_PROMTREE
1993         ---help---
1994           Add support for detecting the unique features of the OLPC
1995           XO hardware.
1996
1997 config OLPC_XO1
1998         tristate "OLPC XO-1 support"
1999         depends on OLPC && MFD_CS5535
2000         ---help---
2001           Add support for non-essential features of the OLPC XO-1 laptop.
2002
2003 endif # X86_32
2004
2005 config AMD_NB
2006         def_bool y
2007         depends on CPU_SUP_AMD && PCI
2008
2009 source "drivers/pcmcia/Kconfig"
2010
2011 source "drivers/pci/hotplug/Kconfig"
2012
2013 config RAPIDIO
2014         bool "RapidIO support"
2015         depends on PCI
2016         default n
2017         help
2018           If you say Y here, the kernel will include drivers and
2019           infrastructure code to support RapidIO interconnect devices.
2020
2021 source "drivers/rapidio/Kconfig"
2022
2023 endmenu
2024
2025
2026 menu "Executable file formats / Emulations"
2027
2028 source "fs/Kconfig.binfmt"
2029
2030 config IA32_EMULATION
2031         bool "IA32 Emulation"
2032         depends on X86_64
2033         select COMPAT_BINFMT_ELF
2034         ---help---
2035           Include code to run 32-bit programs under a 64-bit kernel. You should
2036           likely turn this on, unless you're 100% sure that you don't have any
2037           32-bit programs left.
2038
2039 config IA32_AOUT
2040         tristate "IA32 a.out support"
2041         depends on IA32_EMULATION
2042         ---help---
2043           Support old a.out binaries in the 32bit emulation.
2044
2045 config COMPAT
2046         def_bool y
2047         depends on IA32_EMULATION
2048
2049 config COMPAT_FOR_U64_ALIGNMENT
2050         def_bool COMPAT
2051         depends on X86_64
2052
2053 config SYSVIPC_COMPAT
2054         def_bool y
2055         depends on COMPAT && SYSVIPC
2056
2057 config KEYS_COMPAT
2058         bool
2059         depends on COMPAT && KEYS
2060         default y
2061
2062 endmenu
2063
2064
2065 config HAVE_ATOMIC_IOMAP
2066         def_bool y
2067         depends on X86_32
2068
2069 config HAVE_TEXT_POKE_SMP
2070         bool
2071         select STOP_MACHINE if SMP
2072
2073 source "net/Kconfig"
2074
2075 source "drivers/Kconfig"
2076
2077 source "drivers/firmware/Kconfig"
2078
2079 source "fs/Kconfig"
2080
2081 source "arch/x86/Kconfig.debug"
2082
2083 source "security/Kconfig"
2084
2085 source "crypto/Kconfig"
2086
2087 source "arch/x86/kvm/Kconfig"
2088
2089 source "lib/Kconfig"