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_PCSPKR_PLATFORM
  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_FIND_FIRST_BIT
  68         select GENERIC_IRQ_PROBE
  69         select GENERIC_PENDING_IRQ if SMP
  70         select GENERIC_IRQ_SHOW
  71         select IRQ_FORCED_THREADING
  72         select USE_GENERIC_SMP_HELPERS if SMP
  73         select HAVE_BPF_JIT if (X86_64 && NET)
  74         select CLKEVT_I8253
  75
  76 config INSTRUCTION_DECODER
  77         def_bool (KPROBES || PERF_EVENTS)
  78
  79 config OUTPUT_FORMAT
  80         string
  81         default "elf32-i386" if X86_32
  82         default "elf64-x86-64" if X86_64
  83
  84 config ARCH_DEFCONFIG
  85         string
  86         default "arch/x86/configs/i386_defconfig" if X86_32
  87         default "arch/x86/configs/x86_64_defconfig" if X86_64
  88
  89 config GENERIC_CMOS_UPDATE
  90         def_bool y
  91
  92 config CLOCKSOURCE_WATCHDOG
  93         def_bool y
  94
  95 config GENERIC_CLOCKEVENTS
  96         def_bool y
  97
  98 config ARCH_CLOCKSOURCE_DATA
  99         def_bool y
 100         depends on X86_64
 101
 102 config GENERIC_CLOCKEVENTS_BROADCAST
 103         def_bool y
 104         depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
 105
 106 config LOCKDEP_SUPPORT
 107         def_bool y
 108
 109 config STACKTRACE_SUPPORT
 110         def_bool y
 111
 112 config HAVE_LATENCYTOP_SUPPORT
 113         def_bool y
 114
 115 config MMU
 116         def_bool y
 117
 118 config ZONE_DMA
 119         bool "DMA memory allocation support" if EXPERT
 120         default y
 121         help
 122           DMA memory allocation support allows devices with less than 32-bit
 123           addressing to allocate within the first 16MB of address space.
 124           Disable if no such devices will be used.
 125
 126           If unsure, say Y.
 127
 128 config SBUS
 129         bool
 130
 131 config NEED_DMA_MAP_STATE
 132        def_bool (X86_64 || DMAR || DMA_API_DEBUG)
 133
 134 config NEED_SG_DMA_LENGTH
 135         def_bool y
 136
 137 config GENERIC_ISA_DMA
 138         def_bool ISA_DMA_API
 139
 140 config GENERIC_IOMAP
 141         def_bool y
 142
 143 config GENERIC_BUG
 144         def_bool y
 145         depends on BUG
 146         select GENERIC_BUG_RELATIVE_POINTERS if X86_64
 147
 148 config GENERIC_BUG_RELATIVE_POINTERS
 149         bool
 150
 151 config GENERIC_HWEIGHT
 152         def_bool y
 153
 154 config GENERIC_GPIO
 155         bool
 156
 157 config ARCH_MAY_HAVE_PC_FDC
 158         def_bool ISA_DMA_API
 159
 160 config RWSEM_GENERIC_SPINLOCK
 161         def_bool !X86_XADD
 162
 163 config RWSEM_XCHGADD_ALGORITHM
 164         def_bool X86_XADD
 165
 166 config ARCH_HAS_CPU_IDLE_WAIT
 167         def_bool y
 168
 169 config GENERIC_CALIBRATE_DELAY
 170         def_bool y
 171
 172 config GENERIC_TIME_VSYSCALL
 173         bool
 174         default X86_64
 175
 176 config ARCH_HAS_CPU_RELAX
 177         def_bool y
 178
 179 config ARCH_HAS_DEFAULT_IDLE
 180         def_bool y
 181
 182 config ARCH_HAS_CACHE_LINE_SIZE
 183         def_bool y
 184
 185 config HAVE_SETUP_PER_CPU_AREA
 186         def_bool y
 187
 188 config NEED_PER_CPU_EMBED_FIRST_CHUNK
 189         def_bool y
 190
 191 config NEED_PER_CPU_PAGE_FIRST_CHUNK
 192         def_bool y
 193
 194 config HAVE_CPUMASK_OF_CPU_MAP
 195         def_bool X86_64_SMP
 196
 197 config ARCH_HIBERNATION_POSSIBLE
 198         def_bool y
 199
 200 config ARCH_SUSPEND_POSSIBLE
 201         def_bool y
 202
 203 config ZONE_DMA32
 204         bool
 205         default X86_64
 206
 207 config ARCH_POPULATES_NODE_MAP
 208         def_bool y
 209
 210 config AUDIT_ARCH
 211         bool
 212         default X86_64
 213
 214 config ARCH_SUPPORTS_OPTIMIZED_INLINING
 215         def_bool y
 216
 217 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
 218         def_bool y
 219
 220 config HAVE_INTEL_TXT
 221         def_bool y
 222         depends on EXPERIMENTAL && DMAR && ACPI
 223
 224 config X86_32_SMP
 225         def_bool y
 226         depends on X86_32 && SMP
 227
 228 config X86_64_SMP
 229         def_bool y
 230         depends on X86_64 && SMP
 231
 232 config X86_HT
 233         def_bool y
 234         depends on SMP
 235
 236 config X86_32_LAZY_GS
 237         def_bool y
 238         depends on X86_32 && !CC_STACKPROTECTOR
 239
 240 config ARCH_HWEIGHT_CFLAGS
 241         string
 242         default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
 243         default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64
 244
 245 config KTIME_SCALAR
 246         def_bool X86_32
 247
 248 config ARCH_CPU_PROBE_RELEASE
 249         def_bool y
 250         depends on HOTPLUG_CPU
 251
 252 source "init/Kconfig"
 253 source "kernel/Kconfig.freezer"
 254
 255 menu "Processor type and features"
 256
 257 source "kernel/time/Kconfig"
 258
 259 config SMP
 260         bool "Symmetric multi-processing support"
 261         ---help---
 262           This enables support for systems with more than one CPU. If you have
 263           a system with only one CPU, like most personal computers, say N. If
 264           you have a system with more than one CPU, say Y.
 265
 266           If you say N here, the kernel will run on single and multiprocessor
 267           machines, but will use only one CPU of a multiprocessor machine. If
 268           you say Y here, the kernel will run on many, but not all,
 269           singleprocessor machines. On a singleprocessor machine, the kernel
 270           will run faster if you say N here.
 271
 272           Note that if you say Y here and choose architecture "586" or
 273           "Pentium" under "Processor family", the kernel will not work on 486
 274           architectures. Similarly, multiprocessor kernels for the "PPro"
 275           architecture may not work on all Pentium based boards.
 276
 277           People using multiprocessor machines who say Y here should also say
 278           Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
 279           Management" code will be disabled if you say Y here.
 280
 281           See also <file:Documentation/i386/IO-APIC.txt>,
 282           <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
 283           <http://www.tldp.org/docs.html#howto>.
 284
 285           If you don't know what to do here, say N.
 286
 287 config X86_X2APIC
 288         bool "Support x2apic"
 289         depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
 290         ---help---
 291           This enables x2apic support on CPUs that have this feature.
 292
 293           This allows 32-bit apic IDs (so it can support very large systems),
 294           and accesses the local apic via MSRs not via mmio.
 295
 296           If you don't know what to do here, say N.
 297
 298 config X86_MPPARSE
 299         bool "Enable MPS table" if ACPI
 300         default y
 301         depends on X86_LOCAL_APIC
 302         ---help---
 303           For old smp systems that do not have proper acpi support. Newer systems
 304           (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
 305
 306 config X86_BIGSMP
 307         bool "Support for big SMP systems with more than 8 CPUs"
 308         depends on X86_32 && SMP
 309         ---help---
 310           This option is needed for the systems that have more than 8 CPUs
 311
 312 if X86_32
 313 config X86_EXTENDED_PLATFORM
 314         bool "Support for extended (non-PC) x86 platforms"
 315         default y
 316         ---help---
 317           If you disable this option then the kernel will only support
 318           standard PC platforms. (which covers the vast majority of
 319           systems out there.)
 320
 321           If you enable this option then you'll be able to select support
 322           for the following (non-PC) 32 bit x86 platforms:
 323                 AMD Elan
 324                 NUMAQ (IBM/Sequent)
 325                 RDC R-321x SoC
 326                 SGI 320/540 (Visual Workstation)
 327                 Summit/EXA (IBM x440)
 328                 Unisys ES7000 IA32 series
 329                 Moorestown MID devices
 330
 331           If you have one of these systems, or if you want to build a
 332           generic distribution kernel, say Y here - otherwise say N.
 333 endif
 334
 335 if X86_64
 336 config X86_EXTENDED_PLATFORM
 337         bool "Support for extended (non-PC) x86 platforms"
 338         default y
 339         ---help---
 340           If you disable this option then the kernel will only support
 341           standard PC platforms. (which covers the vast majority of
 342           systems out there.)
 343
 344           If you enable this option then you'll be able to select support
 345           for the following (non-PC) 64 bit x86 platforms:
 346                 ScaleMP vSMP
 347                 SGI Ultraviolet
 348
 349           If you have one of these systems, or if you want to build a
 350           generic distribution kernel, say Y here - otherwise say N.
 351 endif
 352 # This is an alphabetically sorted list of 64 bit extended platforms
 353 # Please maintain the alphabetic order if and when there are additions
 354
 355 config X86_VSMP
 356         bool "ScaleMP vSMP"
 357         select PARAVIRT_GUEST
 358         select PARAVIRT
 359         depends on X86_64 && PCI
 360         depends on X86_EXTENDED_PLATFORM
 361         ---help---
 362           Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
 363           supposed to run on these EM64T-based machines.  Only choose this option
 364           if you have one of these machines.
 365
 366 config X86_UV
 367         bool "SGI Ultraviolet"
 368         depends on X86_64
 369         depends on X86_EXTENDED_PLATFORM
 370         depends on NUMA
 371         depends on X86_X2APIC
 372         ---help---
 373           This option is needed in order to support SGI Ultraviolet systems.
 374           If you don't have one of these, you should say N here.
 375
 376 # Following is an alphabetically sorted list of 32 bit extended platforms
 377 # Please maintain the alphabetic order if and when there are additions
 378
 379 config X86_INTEL_CE
 380         bool "CE4100 TV platform"
 381         depends on PCI
 382         depends on PCI_GODIRECT
 383         depends on X86_32
 384         depends on X86_EXTENDED_PLATFORM
 385         select X86_REBOOTFIXUPS
 386         select OF
 387         select OF_EARLY_FLATTREE
 388         ---help---
 389           Select for the Intel CE media processor (CE4100) SOC.
 390           This option compiles in support for the CE4100 SOC for settop
 391           boxes and media devices.
 392
 393 config X86_INTEL_MID
 394         bool "Intel MID platform support"
 395         depends on X86_32
 396         depends on X86_EXTENDED_PLATFORM
 397         ---help---
 398           Select to build a kernel capable of supporting Intel MID platform
 399           systems which do not have the PCI legacy interfaces (Moorestown,
 400           Medfield). If you are building for a PC class system say N here.
 401
 402 if X86_INTEL_MID
 403
 404 config X86_MRST
 405        bool "Moorestown MID platform"
 406         depends on PCI
 407         depends on PCI_GOANY
 408         depends on X86_IO_APIC
 409         select APB_TIMER
 410         select I2C
 411         select SPI
 412         select INTEL_SCU_IPC
 413         select X86_PLATFORM_DEVICES
 414         ---help---
 415           Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
 416           Internet Device(MID) platform. Moorestown consists of two chips:
 417           Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
 418           Unlike standard x86 PCs, Moorestown does not have many legacy devices
 419           nor standard legacy replacement devices/features. e.g. Moorestown does
 420           not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
 421
 422 endif
 423
 424 config X86_RDC321X
 425         bool "RDC R-321x SoC"
 426         depends on X86_32
 427         depends on X86_EXTENDED_PLATFORM
 428         select M486
 429         select X86_REBOOTFIXUPS
 430         ---help---
 431           This option is needed for RDC R-321x system-on-chip, also known
 432           as R-8610-(G).
 433           If you don't have one of these chips, you should say N here.
 434
 435 config X86_32_NON_STANDARD
 436         bool "Support non-standard 32-bit SMP architectures"
 437         depends on X86_32 && SMP
 438         depends on X86_EXTENDED_PLATFORM
 439         ---help---
 440           This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
 441           subarchitectures.  It is intended for a generic binary kernel.
 442           if you select them all, kernel will probe it one by one. and will
 443           fallback to default.
 444
 445 # Alphabetically sorted list of Non standard 32 bit platforms
 446
 447 config X86_NUMAQ
 448         bool "NUMAQ (IBM/Sequent)"
 449         depends on X86_32_NON_STANDARD
 450         depends on PCI
 451         select NUMA
 452         select X86_MPPARSE
 453         ---help---
 454           This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
 455           NUMA multiquad box. This changes the way that processors are
 456           bootstrapped, and uses Clustered Logical APIC addressing mode instead
 457           of Flat Logical.  You will need a new lynxer.elf file to flash your
 458           firmware with - send email to <Martin.Bligh@us.ibm.com>.
 459
 460 config X86_SUPPORTS_MEMORY_FAILURE
 461         def_bool y
 462         # MCE code calls memory_failure():
 463         depends on X86_MCE
 464         # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
 465         depends on !X86_NUMAQ
 466         # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
 467         depends on X86_64 || !SPARSEMEM
 468         select ARCH_SUPPORTS_MEMORY_FAILURE
 469
 470 config X86_VISWS
 471         bool "SGI 320/540 (Visual Workstation)"
 472         depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
 473         depends on X86_32_NON_STANDARD
 474         ---help---
 475           The SGI Visual Workstation series is an IA32-based workstation
 476           based on SGI systems chips with some legacy PC hardware attached.
 477
 478           Say Y here to create a kernel to run on the SGI 320 or 540.
 479
 480           A kernel compiled for the Visual Workstation will run on general
 481           PCs as well. See <file:Documentation/sgi-visws.txt> for details.
 482
 483 config X86_SUMMIT
 484         bool "Summit/EXA (IBM x440)"
 485         depends on X86_32_NON_STANDARD
 486         ---help---
 487           This option is needed for IBM systems that use the Summit/EXA chipset.
 488           In particular, it is needed for the x440.
 489
 490 config X86_ES7000
 491         bool "Unisys ES7000 IA32 series"
 492         depends on X86_32_NON_STANDARD && X86_BIGSMP
 493         ---help---
 494           Support for Unisys ES7000 systems.  Say 'Y' here if this kernel is
 495           supposed to run on an IA32-based Unisys ES7000 system.
 496
 497 config X86_32_IRIS
 498         tristate "Eurobraille/Iris poweroff module"
 499         depends on X86_32
 500         ---help---
 501           The Iris machines from EuroBraille do not have APM or ACPI support
 502           to shut themselves down properly.  A special I/O sequence is
 503           needed to do so, which is what this module does at
 504           kernel shutdown.
 505
 506           This is only for Iris machines from EuroBraille.
 507
 508           If unused, say N.
 509
 510 config SCHED_OMIT_FRAME_POINTER
 511         def_bool y
 512         prompt "Single-depth WCHAN output"
 513         depends on X86
 514         ---help---
 515           Calculate simpler /proc/<PID>/wchan values. If this option
 516           is disabled then wchan values will recurse back to the
 517           caller function. This provides more accurate wchan values,
 518           at the expense of slightly more scheduling overhead.
 519
 520           If in doubt, say "Y".
 521
 522 menuconfig PARAVIRT_GUEST
 523         bool "Paravirtualized guest support"
 524         ---help---
 525           Say Y here to get to see options related to running Linux under
 526           various hypervisors.  This option alone does not add any kernel code.
 527
 528           If you say N, all options in this submenu will be skipped and disabled.
 529
 530 if PARAVIRT_GUEST
 531
 532 source "arch/x86/xen/Kconfig"
 533
 534 config KVM_CLOCK
 535         bool "KVM paravirtualized clock"
 536         select PARAVIRT
 537         select PARAVIRT_CLOCK
 538         ---help---
 539           Turning on this option will allow you to run a paravirtualized clock
 540           when running over the KVM hypervisor. Instead of relying on a PIT
 541           (or probably other) emulation by the underlying device model, the host
 542           provides the guest with timing infrastructure such as time of day, and
 543           system time
 544
 545 config KVM_GUEST
 546         bool "KVM Guest support"
 547         select PARAVIRT
 548         ---help---
 549           This option enables various optimizations for running under the KVM
 550           hypervisor.
 551
 552 source "arch/x86/lguest/Kconfig"
 553
 554 config PARAVIRT
 555         bool "Enable paravirtualization code"
 556         ---help---
 557           This changes the kernel so it can modify itself when it is run
 558           under a hypervisor, potentially improving performance significantly
 559           over full virtualization.  However, when run without a hypervisor
 560           the kernel is theoretically slower and slightly larger.
 561
 562 config PARAVIRT_SPINLOCKS
 563         bool "Paravirtualization layer for spinlocks"
 564         depends on PARAVIRT && SMP && EXPERIMENTAL
 565         ---help---
 566           Paravirtualized spinlocks allow a pvops backend to replace the
 567           spinlock implementation with something virtualization-friendly
 568           (for example, block the virtual CPU rather than spinning).
 569
 570           Unfortunately the downside is an up to 5% performance hit on
 571           native kernels, with various workloads.
 572
 573           If you are unsure how to answer this question, answer N.
 574
 575 config PARAVIRT_CLOCK
 576         bool
 577
 578 endif
 579
 580 config PARAVIRT_DEBUG
 581         bool "paravirt-ops debugging"
 582         depends on PARAVIRT && DEBUG_KERNEL
 583         ---help---
 584           Enable to debug paravirt_ops internals.  Specifically, BUG if
 585           a paravirt_op is missing when it is called.
 586
 587 config NO_BOOTMEM
 588         def_bool y
 589
 590 config MEMTEST
 591         bool "Memtest"
 592         ---help---
 593           This option adds a kernel parameter 'memtest', which allows memtest
 594           to be set.
 595                 memtest=0, mean disabled; -- default
 596                 memtest=1, mean do 1 test pattern;
 597                 ...
 598                 memtest=4, mean do 4 test patterns.
 599           If you are unsure how to answer this question, answer N.
 600
 601 config X86_SUMMIT_NUMA
 602         def_bool y
 603         depends on X86_32 && NUMA && X86_32_NON_STANDARD
 604
 605 config X86_CYCLONE_TIMER
 606         def_bool y
 607         depends on X86_32_NON_STANDARD
 608
 609 source "arch/x86/Kconfig.cpu"
 610
 611 config HPET_TIMER
 612         def_bool X86_64
 613         prompt "HPET Timer Support" if X86_32
 614         ---help---
 615           Use the IA-PC HPET (High Precision Event Timer) to manage
 616           time in preference to the PIT and RTC, if a HPET is
 617           present.
 618           HPET is the next generation timer replacing legacy 8254s.
 619           The HPET provides a stable time base on SMP
 620           systems, unlike the TSC, but it is more expensive to access,
 621           as it is off-chip.  You can find the HPET spec at
 622           <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
 623
 624           You can safely choose Y here.  However, HPET will only be
 625           activated if the platform and the BIOS support this feature.
 626           Otherwise the 8254 will be used for timing services.
 627
 628           Choose N to continue using the legacy 8254 timer.
 629
 630 config HPET_EMULATE_RTC
 631         def_bool y
 632         depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
 633
 634 config APB_TIMER
 635        def_bool y if MRST
 636        prompt "Langwell APB Timer Support" if X86_MRST
 637        select DW_APB_TIMER
 638        help
 639          APB timer is the replacement for 8254, HPET on X86 MID platforms.
 640          The APBT provides a stable time base on SMP
 641          systems, unlike the TSC, but it is more expensive to access,
 642          as it is off-chip. APB timers are always running regardless of CPU
 643          C states, they are used as per CPU clockevent device when possible.
 644
 645 # Mark as expert because too many people got it wrong.
 646 # The code disables itself when not needed.
 647 config DMI
 648         default y
 649         bool "Enable DMI scanning" if EXPERT
 650         ---help---
 651           Enabled scanning of DMI to identify machine quirks. Say Y
 652           here unless you have verified that your setup is not
 653           affected by entries in the DMI blacklist. Required by PNP
 654           BIOS code.
 655
 656 config GART_IOMMU
 657         bool "GART IOMMU support" if EXPERT
 658         default y
 659         select SWIOTLB
 660         depends on X86_64 && PCI && AMD_NB
 661         ---help---
 662           Support for full DMA access of devices with 32bit memory access only
 663           on systems with more than 3GB. This is usually needed for USB,
 664           sound, many IDE/SATA chipsets and some other devices.
 665           Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
 666           based hardware IOMMU and a software bounce buffer based IOMMU used
 667           on Intel systems and as fallback.
 668           The code is only active when needed (enough memory and limited
 669           device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
 670           too.
 671
 672 config CALGARY_IOMMU
 673         bool "IBM Calgary IOMMU support"
 674         select SWIOTLB
 675         depends on X86_64 && PCI && EXPERIMENTAL
 676         ---help---
 677           Support for hardware IOMMUs in IBM's xSeries x366 and x460
 678           systems. Needed to run systems with more than 3GB of memory
 679           properly with 32-bit PCI devices that do not support DAC
 680           (Double Address Cycle). Calgary also supports bus level
 681           isolation, where all DMAs pass through the IOMMU.  This
 682           prevents them from going anywhere except their intended
 683           destination. This catches hard-to-find kernel bugs and
 684           mis-behaving drivers and devices that do not use the DMA-API
 685           properly to set up their DMA buffers.  The IOMMU can be
 686           turned off at boot time with the iommu=off parameter.
 687           Normally the kernel will make the right choice by itself.
 688           If unsure, say Y.
 689
 690 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
 691         def_bool y
 692         prompt "Should Calgary be enabled by default?"
 693         depends on CALGARY_IOMMU
 694         ---help---
 695           Should Calgary be enabled by default? if you choose 'y', Calgary
 696           will be used (if it exists). If you choose 'n', Calgary will not be
 697           used even if it exists. If you choose 'n' and would like to use
 698           Calgary anyway, pass 'iommu=calgary' on the kernel command line.
 699           If unsure, say Y.
 700
 701 # need this always selected by IOMMU for the VIA workaround
 702 config SWIOTLB
 703         def_bool y if X86_64
 704         ---help---
 705           Support for software bounce buffers used on x86-64 systems
 706           which don't have a hardware IOMMU (e.g. the current generation
 707           of Intel's x86-64 CPUs). Using this PCI devices which can only
 708           access 32-bits of memory can be used on systems with more than
 709           3 GB of memory. If unsure, say Y.
 710
 711 config IOMMU_HELPER
 712         def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
 713
 714 config MAXSMP
 715         bool "Enable Maximum number of SMP Processors and NUMA Nodes"
 716         depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
 717         select CPUMASK_OFFSTACK
 718         ---help---
 719           Enable maximum number of CPUS and NUMA Nodes for this architecture.
 720           If unsure, say N.
 721
 722 config NR_CPUS
 723         int "Maximum number of CPUs" if SMP && !MAXSMP
 724         range 2 8 if SMP && X86_32 && !X86_BIGSMP
 725         range 2 512 if SMP && !MAXSMP
 726         default "1" if !SMP
 727         default "4096" if MAXSMP
 728         default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
 729         default "8" if SMP
 730         ---help---
 731           This allows you to specify the maximum number of CPUs which this
 732           kernel will support.  The maximum supported value is 512 and the
 733           minimum value which makes sense is 2.
 734
 735           This is purely to save memory - each supported CPU adds
 736           approximately eight kilobytes to the kernel image.
 737
 738 config SCHED_SMT
 739         bool "SMT (Hyperthreading) scheduler support"
 740         depends on X86_HT
 741         ---help---
 742           SMT scheduler support improves the CPU scheduler's decision making
 743           when dealing with Intel Pentium 4 chips with HyperThreading at a
 744           cost of slightly increased overhead in some places. If unsure say
 745           N here.
 746
 747 config SCHED_MC
 748         def_bool y
 749         prompt "Multi-core scheduler support"
 750         depends on X86_HT
 751         ---help---
 752           Multi-core scheduler support improves the CPU scheduler's decision
 753           making when dealing with multi-core CPU chips at a cost of slightly
 754           increased overhead in some places. If unsure say N here.
 755
 756 config IRQ_TIME_ACCOUNTING
 757         bool "Fine granularity task level IRQ time accounting"
 758         default n
 759         ---help---
 760           Select this option to enable fine granularity task irq time
 761           accounting. This is done by reading a timestamp on each
 762           transitions between softirq and hardirq state, so there can be a
 763           small performance impact.
 764
 765           If in doubt, say N here.
 766
 767 source "kernel/Kconfig.preempt"
 768
 769 config X86_UP_APIC
 770         bool "Local APIC support on uniprocessors"
 771         depends on X86_32 && !SMP && !X86_32_NON_STANDARD
 772         ---help---
 773           A local APIC (Advanced Programmable Interrupt Controller) is an
 774           integrated interrupt controller in the CPU. If you have a single-CPU
 775           system which has a processor with a local APIC, you can say Y here to
 776           enable and use it. If you say Y here even though your machine doesn't
 777           have a local APIC, then the kernel will still run with no slowdown at
 778           all. The local APIC supports CPU-generated self-interrupts (timer,
 779           performance counters), and the NMI watchdog which detects hard
 780           lockups.
 781
 782 config X86_UP_IOAPIC
 783         bool "IO-APIC support on uniprocessors"
 784         depends on X86_UP_APIC
 785         ---help---
 786           An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
 787           SMP-capable replacement for PC-style interrupt controllers. Most
 788           SMP systems and many recent uniprocessor systems have one.
 789
 790           If you have a single-CPU system with an IO-APIC, you can say Y here
 791           to use it. If you say Y here even though your machine doesn't have
 792           an IO-APIC, then the kernel will still run with no slowdown at all.
 793
 794 config X86_LOCAL_APIC
 795         def_bool y
 796         depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
 797
 798 config X86_IO_APIC
 799         def_bool y
 800         depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC
 801
 802 config X86_VISWS_APIC
 803         def_bool y
 804         depends on X86_32 && X86_VISWS
 805
 806 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
 807         bool "Reroute for broken boot IRQs"
 808         depends on X86_IO_APIC
 809         ---help---
 810           This option enables a workaround that fixes a source of
 811           spurious interrupts. This is recommended when threaded
 812           interrupt handling is used on systems where the generation of
 813           superfluous "boot interrupts" cannot be disabled.
 814
 815           Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
 816           entry in the chipset's IO-APIC is masked (as, e.g. the RT
 817           kernel does during interrupt handling). On chipsets where this
 818           boot IRQ generation cannot be disabled, this workaround keeps
 819           the original IRQ line masked so that only the equivalent "boot
 820           IRQ" is delivered to the CPUs. The workaround also tells the
 821           kernel to set up the IRQ handler on the boot IRQ line. In this
 822           way only one interrupt is delivered to the kernel. Otherwise
 823           the spurious second interrupt may cause the kernel to bring
 824           down (vital) interrupt lines.
 825
 826           Only affects "broken" chipsets. Interrupt sharing may be
 827           increased on these systems.
 828
 829 config X86_MCE
 830         bool "Machine Check / overheating reporting"
 831         ---help---
 832           Machine Check support allows the processor to notify the
 833           kernel if it detects a problem (e.g. overheating, data corruption).
 834           The action the kernel takes depends on the severity of the problem,
 835           ranging from warning messages to halting the machine.
 836
 837 config X86_MCE_INTEL
 838         def_bool y
 839         prompt "Intel MCE features"
 840         depends on X86_MCE && X86_LOCAL_APIC
 841         ---help---
 842            Additional support for intel specific MCE features such as
 843            the thermal monitor.
 844
 845 config X86_MCE_AMD
 846         def_bool y
 847         prompt "AMD MCE features"
 848         depends on X86_MCE && X86_LOCAL_APIC
 849         ---help---
 850            Additional support for AMD specific MCE features such as
 851            the DRAM Error Threshold.
 852
 853 config X86_ANCIENT_MCE
 854         bool "Support for old Pentium 5 / WinChip machine checks"
 855         depends on X86_32 && X86_MCE
 856         ---help---
 857           Include support for machine check handling on old Pentium 5 or WinChip
 858           systems. These typically need to be enabled explicitely on the command
 859           line.
 860
 861 config X86_MCE_THRESHOLD
 862         depends on X86_MCE_AMD || X86_MCE_INTEL
 863         def_bool y
 864
 865 config X86_MCE_INJECT
 866         depends on X86_MCE
 867         tristate "Machine check injector support"
 868         ---help---
 869           Provide support for injecting machine checks for testing purposes.
 870           If you don't know what a machine check is and you don't do kernel
 871           QA it is safe to say n.
 872
 873 config X86_THERMAL_VECTOR
 874         def_bool y
 875         depends on X86_MCE_INTEL
 876
 877 config VM86
 878         bool "Enable VM86 support" if EXPERT
 879         default y
 880         depends on X86_32
 881         ---help---
 882           This option is required by programs like DOSEMU to run 16-bit legacy
 883           code on X86 processors. It also may be needed by software like
 884           XFree86 to initialize some video cards via BIOS. Disabling this
 885           option saves about 6k.
 886
 887 config TOSHIBA
 888         tristate "Toshiba Laptop support"
 889         depends on X86_32
 890         ---help---
 891           This adds a driver to safely access the System Management Mode of
 892           the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
 893           not work on models with a Phoenix BIOS. The System Management Mode
 894           is used to set the BIOS and power saving options on Toshiba portables.
 895
 896           For information on utilities to make use of this driver see the
 897           Toshiba Linux utilities web site at:
 898           <http://www.buzzard.org.uk/toshiba/>.
 899
 900           Say Y if you intend to run this kernel on a Toshiba portable.
 901           Say N otherwise.
 902
 903 config I8K
 904         tristate "Dell laptop support"
 905         select HWMON
 906         ---help---
 907           This adds a driver to safely access the System Management Mode
 908           of the CPU on the Dell Inspiron 8000. The System Management Mode
 909           is used to read cpu temperature and cooling fan status and to
 910           control the fans on the I8K portables.
 911
 912           This driver has been tested only on the Inspiron 8000 but it may
 913           also work with other Dell laptops. You can force loading on other
 914           models by passing the parameter `force=1' to the module. Use at
 915           your own risk.
 916
 917           For information on utilities to make use of this driver see the
 918           I8K Linux utilities web site at:
 919           <http://people.debian.org/~dz/i8k/>
 920
 921           Say Y if you intend to run this kernel on a Dell Inspiron 8000.
 922           Say N otherwise.
 923
 924 config X86_REBOOTFIXUPS
 925         bool "Enable X86 board specific fixups for reboot"
 926         depends on X86_32
 927         ---help---
 928           This enables chipset and/or board specific fixups to be done
 929           in order to get reboot to work correctly. This is only needed on
 930           some combinations of hardware and BIOS. The symptom, for which
 931           this config is intended, is when reboot ends with a stalled/hung
 932           system.
 933
 934           Currently, the only fixup is for the Geode machines using
 935           CS5530A and CS5536 chipsets and the RDC R-321x SoC.
 936
 937           Say Y if you want to enable the fixup. Currently, it's safe to
 938           enable this option even if you don't need it.
 939           Say N otherwise.
 940
 941 config MICROCODE
 942         tristate "/dev/cpu/microcode - microcode support"
 943         select FW_LOADER
 944         ---help---
 945           If you say Y here, you will be able to update the microcode on
 946           certain Intel and AMD processors. The Intel support is for the
 947           IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
 948           Pentium 4, Xeon etc. The AMD support is for family 0x10 and
 949           0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
 950           You will obviously need the actual microcode binary data itself
 951           which is not shipped with the Linux kernel.
 952
 953           This option selects the general module only, you need to select
 954           at least one vendor specific module as well.
 955
 956           To compile this driver as a module, choose M here: the
 957           module will be called microcode.
 958
 959 config MICROCODE_INTEL
 960         bool "Intel microcode patch loading support"
 961         depends on MICROCODE
 962         default MICROCODE
 963         select FW_LOADER
 964         ---help---
 965           This options enables microcode patch loading support for Intel
 966           processors.
 967
 968           For latest news and information on obtaining all the required
 969           Intel ingredients for this driver, check:
 970           <http://www.urbanmyth.org/microcode/>.
 971
 972 config MICROCODE_AMD
 973         bool "AMD microcode patch loading support"
 974         depends on MICROCODE
 975         select FW_LOADER
 976         ---help---
 977           If you select this option, microcode patch loading support for AMD
 978           processors will be enabled.
 979
 980 config MICROCODE_OLD_INTERFACE
 981         def_bool y
 982         depends on MICROCODE
 983
 984 config X86_MSR
 985         tristate "/dev/cpu/*/msr - Model-specific register support"
 986         ---help---
 987           This device gives privileged processes access to the x86
 988           Model-Specific Registers (MSRs).  It is a character device with
 989           major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
 990           MSR accesses are directed to a specific CPU on multi-processor
 991           systems.
 992
 993 config X86_CPUID
 994         tristate "/dev/cpu/*/cpuid - CPU information support"
 995         ---help---
 996           This device gives processes access to the x86 CPUID instruction to
 997           be executed on a specific processor.  It is a character device
 998           with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
 999           /dev/cpu/31/cpuid.
1000
1001 choice
1002         prompt "High Memory Support"
1003         default HIGHMEM64G if X86_NUMAQ
1004         default HIGHMEM4G
1005         depends on X86_32
1006
1007 config NOHIGHMEM
1008         bool "off"
1009         depends on !X86_NUMAQ
1010         ---help---
1011           Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1012           However, the address space of 32-bit x86 processors is only 4
1013           Gigabytes large. That means that, if you have a large amount of
1014           physical memory, not all of it can be "permanently mapped" by the
1015           kernel. The physical memory that's not permanently mapped is called
1016           "high memory".
1017
1018           If you are compiling a kernel which will never run on a machine with
1019           more than 1 Gigabyte total physical RAM, answer "off" here (default
1020           choice and suitable for most users). This will result in a "3GB/1GB"
1021           split: 3GB are mapped so that each process sees a 3GB virtual memory
1022           space and the remaining part of the 4GB virtual memory space is used
1023           by the kernel to permanently map as much physical memory as
1024           possible.
1025
1026           If the machine has between 1 and 4 Gigabytes physical RAM, then
1027           answer "4GB" here.
1028
1029           If more than 4 Gigabytes is used then answer "64GB" here. This
1030           selection turns Intel PAE (Physical Address Extension) mode on.
1031           PAE implements 3-level paging on IA32 processors. PAE is fully
1032           supported by Linux, PAE mode is implemented on all recent Intel
1033           processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1034           then the kernel will not boot on CPUs that don't support PAE!
1035
1036           The actual amount of total physical memory will either be
1037           auto detected or can be forced by using a kernel command line option
1038           such as "mem=256M". (Try "man bootparam" or see the documentation of
1039           your boot loader (lilo or loadlin) about how to pass options to the
1040           kernel at boot time.)
1041
1042           If unsure, say "off".
1043
1044 config HIGHMEM4G
1045         bool "4GB"
1046         depends on !X86_NUMAQ
1047         ---help---
1048           Select this if you have a 32-bit processor and between 1 and 4
1049           gigabytes of physical RAM.
1050
1051 config HIGHMEM64G
1052         bool "64GB"
1053         depends on !M386 && !M486
1054         select X86_PAE
1055         ---help---
1056           Select this if you have a 32-bit processor and more than 4
1057           gigabytes of physical RAM.
1058
1059 endchoice
1060
1061 choice
1062         depends on EXPERIMENTAL
1063         prompt "Memory split" if EXPERT
1064         default VMSPLIT_3G
1065         depends on X86_32
1066         ---help---
1067           Select the desired split between kernel and user memory.
1068
1069           If the address range available to the kernel is less than the
1070           physical memory installed, the remaining memory will be available
1071           as "high memory". Accessing high memory is a little more costly
1072           than low memory, as it needs to be mapped into the kernel first.
1073           Note that increasing the kernel address space limits the range
1074           available to user programs, making the address space there
1075           tighter.  Selecting anything other than the default 3G/1G split
1076           will also likely make your kernel incompatible with binary-only
1077           kernel modules.
1078
1079           If you are not absolutely sure what you are doing, leave this
1080           option alone!
1081
1082         config VMSPLIT_3G
1083                 bool "3G/1G user/kernel split"
1084         config VMSPLIT_3G_OPT
1085                 depends on !X86_PAE
1086                 bool "3G/1G user/kernel split (for full 1G low memory)"
1087         config VMSPLIT_2G
1088                 bool "2G/2G user/kernel split"
1089         config VMSPLIT_2G_OPT
1090                 depends on !X86_PAE
1091                 bool "2G/2G user/kernel split (for full 2G low memory)"
1092         config VMSPLIT_1G
1093                 bool "1G/3G user/kernel split"
1094 endchoice
1095
1096 config PAGE_OFFSET
1097         hex
1098         default 0xB0000000 if VMSPLIT_3G_OPT
1099         default 0x80000000 if VMSPLIT_2G
1100         default 0x78000000 if VMSPLIT_2G_OPT
1101         default 0x40000000 if VMSPLIT_1G
1102         default 0xC0000000
1103         depends on X86_32
1104
1105 config HIGHMEM
1106         def_bool y
1107         depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1108
1109 config X86_PAE
1110         bool "PAE (Physical Address Extension) Support"
1111         depends on X86_32 && !HIGHMEM4G
1112         ---help---
1113           PAE is required for NX support, and furthermore enables
1114           larger swapspace support for non-overcommit purposes. It
1115           has the cost of more pagetable lookup overhead, and also
1116           consumes more pagetable space per process.
1117
1118 config ARCH_PHYS_ADDR_T_64BIT
1119         def_bool X86_64 || X86_PAE
1120
1121 config ARCH_DMA_ADDR_T_64BIT
1122         def_bool X86_64 || HIGHMEM64G
1123
1124 config DIRECT_GBPAGES
1125         bool "Enable 1GB pages for kernel pagetables" if EXPERT
1126         default y
1127         depends on X86_64
1128         ---help---
1129           Allow the kernel linear mapping to use 1GB pages on CPUs that
1130           support it. This can improve the kernel's performance a tiny bit by
1131           reducing TLB pressure. If in doubt, say "Y".
1132
1133 # Common NUMA Features
1134 config NUMA
1135         bool "Numa Memory Allocation and Scheduler Support"
1136         depends on SMP
1137         depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1138         default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1139         ---help---
1140           Enable NUMA (Non Uniform Memory Access) support.
1141
1142           The kernel will try to allocate memory used by a CPU on the
1143           local memory controller of the CPU and add some more
1144           NUMA awareness to the kernel.
1145
1146           For 64-bit this is recommended if the system is Intel Core i7
1147           (or later), AMD Opteron, or EM64T NUMA.
1148
1149           For 32-bit this is only needed on (rare) 32-bit-only platforms
1150           that support NUMA topologies, such as NUMAQ / Summit, or if you
1151           boot a 32-bit kernel on a 64-bit NUMA platform.
1152
1153           Otherwise, you should say N.
1154
1155 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1156         depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1157
1158 config AMD_NUMA
1159         def_bool y
1160         prompt "Old style AMD Opteron NUMA detection"
1161         depends on X86_64 && NUMA && PCI
1162         ---help---
1163           Enable AMD NUMA node topology detection.  You should say Y here if
1164           you have a multi processor AMD system. This uses an old method to
1165           read the NUMA configuration directly from the builtin Northbridge
1166           of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1167           which also takes priority if both are compiled in.
1168
1169 config X86_64_ACPI_NUMA
1170         def_bool y
1171         prompt "ACPI NUMA detection"
1172         depends on X86_64 && NUMA && ACPI && PCI
1173         select ACPI_NUMA
1174         ---help---
1175           Enable ACPI SRAT based node topology detection.
1176
1177 # Some NUMA nodes have memory ranges that span
1178 # other nodes.  Even though a pfn is valid and
1179 # between a node's start and end pfns, it may not
1180 # reside on that node.  See memmap_init_zone()
1181 # for details.
1182 config NODES_SPAN_OTHER_NODES
1183         def_bool y
1184         depends on X86_64_ACPI_NUMA
1185
1186 config NUMA_EMU
1187         bool "NUMA emulation"
1188         depends on NUMA
1189         ---help---
1190           Enable NUMA emulation. A flat machine will be split
1191           into virtual nodes when booted with "numa=fake=N", where N is the
1192           number of nodes. This is only useful for debugging.
1193
1194 config NODES_SHIFT
1195         int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1196         range 1 10
1197         default "10" if MAXSMP
1198         default "6" if X86_64
1199         default "4" if X86_NUMAQ
1200         default "3"
1201         depends on NEED_MULTIPLE_NODES
1202         ---help---
1203           Specify the maximum number of NUMA Nodes available on the target
1204           system.  Increases memory reserved to accommodate various tables.
1205
1206 config HAVE_ARCH_BOOTMEM
1207         def_bool y
1208         depends on X86_32 && NUMA
1209
1210 config HAVE_ARCH_ALLOC_REMAP
1211         def_bool y
1212         depends on X86_32 && NUMA
1213
1214 config ARCH_HAVE_MEMORY_PRESENT
1215         def_bool y
1216         depends on X86_32 && DISCONTIGMEM
1217
1218 config NEED_NODE_MEMMAP_SIZE
1219         def_bool y
1220         depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1221
1222 config ARCH_FLATMEM_ENABLE
1223         def_bool y
1224         depends on X86_32 && !NUMA
1225
1226 config ARCH_DISCONTIGMEM_ENABLE
1227         def_bool y
1228         depends on NUMA && X86_32
1229
1230 config ARCH_DISCONTIGMEM_DEFAULT
1231         def_bool y
1232         depends on NUMA && X86_32
1233
1234 config ARCH_SPARSEMEM_ENABLE
1235         def_bool y
1236         depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1237         select SPARSEMEM_STATIC if X86_32
1238         select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1239
1240 config ARCH_SPARSEMEM_DEFAULT
1241         def_bool y
1242         depends on X86_64
1243
1244 config ARCH_SELECT_MEMORY_MODEL
1245         def_bool y
1246         depends on ARCH_SPARSEMEM_ENABLE
1247
1248 config ARCH_MEMORY_PROBE
1249         def_bool X86_64
1250         depends on MEMORY_HOTPLUG
1251
1252 config ARCH_PROC_KCORE_TEXT
1253         def_bool y
1254         depends on X86_64 && PROC_KCORE
1255
1256 config ILLEGAL_POINTER_VALUE
1257        hex
1258        default 0 if X86_32
1259        default 0xdead000000000000 if X86_64
1260
1261 source "mm/Kconfig"
1262
1263 config HIGHPTE
1264         bool "Allocate 3rd-level pagetables from highmem"
1265         depends on HIGHMEM
1266         ---help---
1267           The VM uses one page table entry for each page of physical memory.
1268           For systems with a lot of RAM, this can be wasteful of precious
1269           low memory.  Setting this option will put user-space page table
1270           entries in high memory.
1271
1272 config X86_CHECK_BIOS_CORRUPTION
1273         bool "Check for low memory corruption"
1274         ---help---
1275           Periodically check for memory corruption in low memory, which
1276           is suspected to be caused by BIOS.  Even when enabled in the
1277           configuration, it is disabled at runtime.  Enable it by
1278           setting "memory_corruption_check=1" on the kernel command
1279           line.  By default it scans the low 64k of memory every 60
1280           seconds; see the memory_corruption_check_size and
1281           memory_corruption_check_period parameters in
1282           Documentation/kernel-parameters.txt to adjust this.
1283
1284           When enabled with the default parameters, this option has
1285           almost no overhead, as it reserves a relatively small amount
1286           of memory and scans it infrequently.  It both detects corruption
1287           and prevents it from affecting the running system.
1288
1289           It is, however, intended as a diagnostic tool; if repeatable
1290           BIOS-originated corruption always affects the same memory,
1291           you can use memmap= to prevent the kernel from using that
1292           memory.
1293
1294 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1295         bool "Set the default setting of memory_corruption_check"
1296         depends on X86_CHECK_BIOS_CORRUPTION
1297         default y
1298         ---help---
1299           Set whether the default state of memory_corruption_check is
1300           on or off.
1301
1302 config X86_RESERVE_LOW
1303         int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1304         default 64
1305         range 4 640
1306         ---help---
1307           Specify the amount of low memory to reserve for the BIOS.
1308
1309           The first page contains BIOS data structures that the kernel
1310           must not use, so that page must always be reserved.
1311
1312           By default we reserve the first 64K of physical RAM, as a
1313           number of BIOSes are known to corrupt that memory range
1314           during events such as suspend/resume or monitor cable
1315           insertion, so it must not be used by the kernel.
1316
1317           You can set this to 4 if you are absolutely sure that you
1318           trust the BIOS to get all its memory reservations and usages
1319           right.  If you know your BIOS have problems beyond the
1320           default 64K area, you can set this to 640 to avoid using the
1321           entire low memory range.
1322
1323           If you have doubts about the BIOS (e.g. suspend/resume does
1324           not work or there's kernel crashes after certain hardware
1325           hotplug events) then you might want to enable
1326           X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1327           typical corruption patterns.
1328
1329           Leave this to the default value of 64 if you are unsure.
1330
1331 config MATH_EMULATION
1332         bool
1333         prompt "Math emulation" if X86_32
1334         ---help---
1335           Linux can emulate a math coprocessor (used for floating point
1336           operations) if you don't have one. 486DX and Pentium processors have
1337           a math coprocessor built in, 486SX and 386 do not, unless you added
1338           a 487DX or 387, respectively. (The messages during boot time can
1339           give you some hints here ["man dmesg"].) Everyone needs either a
1340           coprocessor or this emulation.
1341
1342           If you don't have a math coprocessor, you need to say Y here; if you
1343           say Y here even though you have a coprocessor, the coprocessor will
1344           be used nevertheless. (This behavior can be changed with the kernel
1345           command line option "no387", which comes handy if your coprocessor
1346           is broken. Try "man bootparam" or see the documentation of your boot
1347           loader (lilo or loadlin) about how to pass options to the kernel at
1348           boot time.) This means that it is a good idea to say Y here if you
1349           intend to use this kernel on different machines.
1350
1351           More information about the internals of the Linux math coprocessor
1352           emulation can be found in <file:arch/x86/math-emu/README>.
1353
1354           If you are not sure, say Y; apart from resulting in a 66 KB bigger
1355           kernel, it won't hurt.
1356
1357 config MTRR
1358         def_bool y
1359         prompt "MTRR (Memory Type Range Register) support" if EXPERT
1360         ---help---
1361           On Intel P6 family processors (Pentium Pro, Pentium II and later)
1362           the Memory Type Range Registers (MTRRs) may be used to control
1363           processor access to memory ranges. This is most useful if you have
1364           a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1365           allows bus write transfers to be combined into a larger transfer
1366           before bursting over the PCI/AGP bus. This can increase performance
1367           of image write operations 2.5 times or more. Saying Y here creates a
1368           /proc/mtrr file which may be used to manipulate your processor's
1369           MTRRs. Typically the X server should use this.
1370
1371           This code has a reasonably generic interface so that similar
1372           control registers on other processors can be easily supported
1373           as well:
1374
1375           The Cyrix 6x86, 6x86MX and M II processors have Address Range
1376           Registers (ARRs) which provide a similar functionality to MTRRs. For
1377           these, the ARRs are used to emulate the MTRRs.
1378           The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1379           MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1380           write-combining. All of these processors are supported by this code
1381           and it makes sense to say Y here if you have one of them.
1382
1383           Saying Y here also fixes a problem with buggy SMP BIOSes which only
1384           set the MTRRs for the boot CPU and not for the secondary CPUs. This
1385           can lead to all sorts of problems, so it's good to say Y here.
1386
1387           You can safely say Y even if your machine doesn't have MTRRs, you'll
1388           just add about 9 KB to your kernel.
1389
1390           See <file:Documentation/x86/mtrr.txt> for more information.
1391
1392 config MTRR_SANITIZER
1393         def_bool y
1394         prompt "MTRR cleanup support"
1395         depends on MTRR
1396         ---help---
1397           Convert MTRR layout from continuous to discrete, so X drivers can
1398           add writeback entries.
1399
1400           Can be disabled with disable_mtrr_cleanup on the kernel command line.
1401           The largest mtrr entry size for a continuous block can be set with
1402           mtrr_chunk_size.
1403
1404           If unsure, say Y.
1405
1406 config MTRR_SANITIZER_ENABLE_DEFAULT
1407         int "MTRR cleanup enable value (0-1)"
1408         range 0 1
1409         default "0"
1410         depends on MTRR_SANITIZER
1411         ---help---
1412           Enable mtrr cleanup default value
1413
1414 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1415         int "MTRR cleanup spare reg num (0-7)"
1416         range 0 7
1417         default "1"
1418         depends on MTRR_SANITIZER
1419         ---help---
1420           mtrr cleanup spare entries default, it can be changed via
1421           mtrr_spare_reg_nr=N on the kernel command line.
1422
1423 config X86_PAT
1424         def_bool y
1425         prompt "x86 PAT support" if EXPERT
1426         depends on MTRR
1427         ---help---
1428           Use PAT attributes to setup page level cache control.
1429
1430           PATs are the modern equivalents of MTRRs and are much more
1431           flexible than MTRRs.
1432
1433           Say N here if you see bootup problems (boot crash, boot hang,
1434           spontaneous reboots) or a non-working video driver.
1435
1436           If unsure, say Y.
1437
1438 config ARCH_USES_PG_UNCACHED
1439         def_bool y
1440         depends on X86_PAT
1441
1442 config EFI
1443         bool "EFI runtime service support"
1444         depends on ACPI
1445         ---help---
1446           This enables the kernel to use EFI runtime services that are
1447           available (such as the EFI variable services).
1448
1449           This option is only useful on systems that have EFI firmware.
1450           In addition, you should use the latest ELILO loader available
1451           at <http://elilo.sourceforge.net> in order to take advantage
1452           of EFI runtime services. However, even with this option, the
1453           resultant kernel should continue to boot on existing non-EFI
1454           platforms.
1455
1456 config SECCOMP
1457         def_bool y
1458         prompt "Enable seccomp to safely compute untrusted bytecode"
1459         ---help---
1460           This kernel feature is useful for number crunching applications
1461           that may need to compute untrusted bytecode during their
1462           execution. By using pipes or other transports made available to
1463           the process as file descriptors supporting the read/write
1464           syscalls, it's possible to isolate those applications in
1465           their own address space using seccomp. Once seccomp is
1466           enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1467           and the task is only allowed to execute a few safe syscalls
1468           defined by each seccomp mode.
1469
1470           If unsure, say Y. Only embedded should say N here.
1471
1472 config CC_STACKPROTECTOR
1473         bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1474         ---help---
1475           This option turns on the -fstack-protector GCC feature. This
1476           feature puts, at the beginning of functions, a canary value on
1477           the stack just before the return address, and validates
1478           the value just before actually returning.  Stack based buffer
1479           overflows (that need to overwrite this return address) now also
1480           overwrite the canary, which gets detected and the attack is then
1481           neutralized via a kernel panic.
1482
1483           This feature requires gcc version 4.2 or above, or a distribution
1484           gcc with the feature backported. Older versions are automatically
1485           detected and for those versions, this configuration option is
1486           ignored. (and a warning is printed during bootup)
1487
1488 source kernel/Kconfig.hz
1489
1490 config KEXEC
1491         bool "kexec system call"
1492         ---help---
1493           kexec is a system call that implements the ability to shutdown your
1494           current kernel, and to start another kernel.  It is like a reboot
1495           but it is independent of the system firmware.   And like a reboot
1496           you can start any kernel with it, not just Linux.
1497
1498           The name comes from the similarity to the exec system call.
1499
1500           It is an ongoing process to be certain the hardware in a machine
1501           is properly shutdown, so do not be surprised if this code does not
1502           initially work for you.  It may help to enable device hotplugging
1503           support.  As of this writing the exact hardware interface is
1504           strongly in flux, so no good recommendation can be made.
1505
1506 config CRASH_DUMP
1507         bool "kernel crash dumps"
1508         depends on X86_64 || (X86_32 && HIGHMEM)
1509         ---help---
1510           Generate crash dump after being started by kexec.
1511           This should be normally only set in special crash dump kernels
1512           which are loaded in the main kernel with kexec-tools into
1513           a specially reserved region and then later executed after
1514           a crash by kdump/kexec. The crash dump kernel must be compiled
1515           to a memory address not used by the main kernel or BIOS using
1516           PHYSICAL_START, or it must be built as a relocatable image
1517           (CONFIG_RELOCATABLE=y).
1518           For more details see Documentation/kdump/kdump.txt
1519
1520 config KEXEC_JUMP
1521         bool "kexec jump (EXPERIMENTAL)"
1522         depends on EXPERIMENTAL
1523         depends on KEXEC && HIBERNATION
1524         ---help---
1525           Jump between original kernel and kexeced kernel and invoke
1526           code in physical address mode via KEXEC
1527
1528 config PHYSICAL_START
1529         hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1530         default "0x1000000"
1531         ---help---
1532           This gives the physical address where the kernel is loaded.
1533
1534           If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1535           bzImage will decompress itself to above physical address and
1536           run from there. Otherwise, bzImage will run from the address where
1537           it has been loaded by the boot loader and will ignore above physical
1538           address.
1539
1540           In normal kdump cases one does not have to set/change this option
1541           as now bzImage can be compiled as a completely relocatable image
1542           (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1543           address. This option is mainly useful for the folks who don't want
1544           to use a bzImage for capturing the crash dump and want to use a
1545           vmlinux instead. vmlinux is not relocatable hence a kernel needs
1546           to be specifically compiled to run from a specific memory area
1547           (normally a reserved region) and this option comes handy.
1548
1549           So if you are using bzImage for capturing the crash dump,
1550           leave the value here unchanged to 0x1000000 and set
1551           CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
1552           for capturing the crash dump change this value to start of
1553           the reserved region.  In other words, it can be set based on
1554           the "X" value as specified in the "crashkernel=YM@XM"
1555           command line boot parameter passed to the panic-ed
1556           kernel. Please take a look at Documentation/kdump/kdump.txt
1557           for more details about crash dumps.
1558
1559           Usage of bzImage for capturing the crash dump is recommended as
1560           one does not have to build two kernels. Same kernel can be used
1561           as production kernel and capture kernel. Above option should have
1562           gone away after relocatable bzImage support is introduced. But it
1563           is present because there are users out there who continue to use
1564           vmlinux for dump capture. This option should go away down the
1565           line.
1566
1567           Don't change this unless you know what you are doing.
1568
1569 config RELOCATABLE
1570         bool "Build a relocatable kernel"
1571         default y
1572         ---help---
1573           This builds a kernel image that retains relocation information
1574           so it can be loaded someplace besides the default 1MB.
1575           The relocations tend to make the kernel binary about 10% larger,
1576           but are discarded at runtime.
1577
1578           One use is for the kexec on panic case where the recovery kernel
1579           must live at a different physical address than the primary
1580           kernel.
1581
1582           Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1583           it has been loaded at and the compile time physical address
1584           (CONFIG_PHYSICAL_START) is ignored.
1585
1586 # Relocation on x86-32 needs some additional build support
1587 config X86_NEED_RELOCS
1588         def_bool y
1589         depends on X86_32 && RELOCATABLE
1590
1591 config PHYSICAL_ALIGN
1592         hex "Alignment value to which kernel should be aligned" if X86_32
1593         default "0x1000000"
1594         range 0x2000 0x1000000
1595         ---help---
1596           This value puts the alignment restrictions on physical address
1597           where kernel is loaded and run from. Kernel is compiled for an
1598           address which meets above alignment restriction.
1599
1600           If bootloader loads the kernel at a non-aligned address and
1601           CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1602           address aligned to above value and run from there.
1603
1604           If bootloader loads the kernel at a non-aligned address and
1605           CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1606           load address and decompress itself to the address it has been
1607           compiled for and run from there. The address for which kernel is
1608           compiled already meets above alignment restrictions. Hence the
1609           end result is that kernel runs from a physical address meeting
1610           above alignment restrictions.
1611
1612           Don't change this unless you know what you are doing.
1613
1614 config HOTPLUG_CPU
1615         bool "Support for hot-pluggable CPUs"
1616         depends on SMP && HOTPLUG
1617         ---help---
1618           Say Y here to allow turning CPUs off and on. CPUs can be
1619           controlled through /sys/devices/system/cpu.
1620           ( Note: power management support will enable this option
1621             automatically on SMP systems. )
1622           Say N if you want to disable CPU hotplug.
1623
1624 config COMPAT_VDSO
1625         def_bool y
1626         prompt "Compat VDSO support"
1627         depends on X86_32 || IA32_EMULATION
1628         ---help---
1629           Map the 32-bit VDSO to the predictable old-style address too.
1630
1631           Say N here if you are running a sufficiently recent glibc
1632           version (2.3.3 or later), to remove the high-mapped
1633           VDSO mapping and to exclusively use the randomized VDSO.
1634
1635           If unsure, say Y.
1636
1637 config CMDLINE_BOOL
1638         bool "Built-in kernel command line"
1639         ---help---
1640           Allow for specifying boot arguments to the kernel at
1641           build time.  On some systems (e.g. embedded ones), it is
1642           necessary or convenient to provide some or all of the
1643           kernel boot arguments with the kernel itself (that is,
1644           to not rely on the boot loader to provide them.)
1645
1646           To compile command line arguments into the kernel,
1647           set this option to 'Y', then fill in the
1648           the boot arguments in CONFIG_CMDLINE.
1649
1650           Systems with fully functional boot loaders (i.e. non-embedded)
1651           should leave this option set to 'N'.
1652
1653 config CMDLINE
1654         string "Built-in kernel command string"
1655         depends on CMDLINE_BOOL
1656         default ""
1657         ---help---
1658           Enter arguments here that should be compiled into the kernel
1659           image and used at boot time.  If the boot loader provides a
1660           command line at boot time, it is appended to this string to
1661           form the full kernel command line, when the system boots.
1662
1663           However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1664           change this behavior.
1665
1666           In most cases, the command line (whether built-in or provided
1667           by the boot loader) should specify the device for the root
1668           file system.
1669
1670 config CMDLINE_OVERRIDE
1671         bool "Built-in command line overrides boot loader arguments"
1672         depends on CMDLINE_BOOL
1673         ---help---
1674           Set this option to 'Y' to have the kernel ignore the boot loader
1675           command line, and use ONLY the built-in command line.
1676
1677           This is used to work around broken boot loaders.  This should
1678           be set to 'N' under normal conditions.
1679
1680 endmenu
1681
1682 config ARCH_ENABLE_MEMORY_HOTPLUG
1683         def_bool y
1684         depends on X86_64 || (X86_32 && HIGHMEM)
1685
1686 config ARCH_ENABLE_MEMORY_HOTREMOVE
1687         def_bool y
1688         depends on MEMORY_HOTPLUG
1689
1690 config USE_PERCPU_NUMA_NODE_ID
1691         def_bool y
1692         depends on NUMA
1693
1694 menu "Power management and ACPI options"
1695
1696 config ARCH_HIBERNATION_HEADER
1697         def_bool y
1698         depends on X86_64 && HIBERNATION
1699
1700 source "kernel/power/Kconfig"
1701
1702 source "drivers/acpi/Kconfig"
1703
1704 source "drivers/sfi/Kconfig"
1705
1706 config X86_APM_BOOT
1707         def_bool y
1708         depends on APM || APM_MODULE
1709
1710 menuconfig APM
1711         tristate "APM (Advanced Power Management) BIOS support"
1712         depends on X86_32 && PM_SLEEP
1713         ---help---
1714           APM is a BIOS specification for saving power using several different
1715           techniques. This is mostly useful for battery powered laptops with
1716           APM compliant BIOSes. If you say Y here, the system time will be
1717           reset after a RESUME operation, the /proc/apm device will provide
1718           battery status information, and user-space programs will receive
1719           notification of APM "events" (e.g. battery status change).
1720
1721           If you select "Y" here, you can disable actual use of the APM
1722           BIOS by passing the "apm=off" option to the kernel at boot time.
1723
1724           Note that the APM support is almost completely disabled for
1725           machines with more than one CPU.
1726
1727           In order to use APM, you will need supporting software. For location
1728           and more information, read <file:Documentation/power/pm.txt> and the
1729           Battery Powered Linux mini-HOWTO, available from
1730           <http://www.tldp.org/docs.html#howto>.
1731
1732           This driver does not spin down disk drives (see the hdparm(8)
1733           manpage ("man 8 hdparm") for that), and it doesn't turn off
1734           VESA-compliant "green" monitors.
1735
1736           This driver does not support the TI 4000M TravelMate and the ACER
1737           486/DX4/75 because they don't have compliant BIOSes. Many "green"
1738           desktop machines also don't have compliant BIOSes, and this driver
1739           may cause those machines to panic during the boot phase.
1740
1741           Generally, if you don't have a battery in your machine, there isn't
1742           much point in using this driver and you should say N. If you get
1743           random kernel OOPSes or reboots that don't seem to be related to
1744           anything, try disabling/enabling this option (or disabling/enabling
1745           APM in your BIOS).
1746
1747           Some other things you should try when experiencing seemingly random,
1748           "weird" problems:
1749
1750           1) make sure that you have enough swap space and that it is
1751           enabled.
1752           2) pass the "no-hlt" option to the kernel
1753           3) switch on floating point emulation in the kernel and pass
1754           the "no387" option to the kernel
1755           4) pass the "floppy=nodma" option to the kernel
1756           5) pass the "mem=4M" option to the kernel (thereby disabling
1757           all but the first 4 MB of RAM)
1758           6) make sure that the CPU is not over clocked.
1759           7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1760           8) disable the cache from your BIOS settings
1761           9) install a fan for the video card or exchange video RAM
1762           10) install a better fan for the CPU
1763           11) exchange RAM chips
1764           12) exchange the motherboard.
1765
1766           To compile this driver as a module, choose M here: the
1767           module will be called apm.
1768
1769 if APM
1770
1771 config APM_IGNORE_USER_SUSPEND
1772         bool "Ignore USER SUSPEND"
1773         ---help---
1774           This option will ignore USER SUSPEND requests. On machines with a
1775           compliant APM BIOS, you want to say N. However, on the NEC Versa M
1776           series notebooks, it is necessary to say Y because of a BIOS bug.
1777
1778 config APM_DO_ENABLE
1779         bool "Enable PM at boot time"
1780         ---help---
1781           Enable APM features at boot time. From page 36 of the APM BIOS
1782           specification: "When disabled, the APM BIOS does not automatically
1783           power manage devices, enter the Standby State, enter the Suspend
1784           State, or take power saving steps in response to CPU Idle calls."
1785           This driver will make CPU Idle calls when Linux is idle (unless this
1786           feature is turned off -- see "Do CPU IDLE calls", below). This
1787           should always save battery power, but more complicated APM features
1788           will be dependent on your BIOS implementation. You may need to turn
1789           this option off if your computer hangs at boot time when using APM
1790           support, or if it beeps continuously instead of suspending. Turn
1791           this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1792           T400CDT. This is off by default since most machines do fine without
1793           this feature.
1794
1795 config APM_CPU_IDLE
1796         bool "Make CPU Idle calls when idle"
1797         ---help---
1798           Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1799           On some machines, this can activate improved power savings, such as
1800           a slowed CPU clock rate, when the machine is idle. These idle calls
1801           are made after the idle loop has run for some length of time (e.g.,
1802           333 mS). On some machines, this will cause a hang at boot time or
1803           whenever the CPU becomes idle. (On machines with more than one CPU,
1804           this option does nothing.)
1805
1806 config APM_DISPLAY_BLANK
1807         bool "Enable console blanking using APM"
1808         ---help---
1809           Enable console blanking using the APM. Some laptops can use this to
1810           turn off the LCD backlight when the screen blanker of the Linux
1811           virtual console blanks the screen. Note that this is only used by
1812           the virtual console screen blanker, and won't turn off the backlight
1813           when using the X Window system. This also doesn't have anything to
1814           do with your VESA-compliant power-saving monitor. Further, this
1815           option doesn't work for all laptops -- it might not turn off your
1816           backlight at all, or it might print a lot of errors to the console,
1817           especially if you are using gpm.
1818
1819 config APM_ALLOW_INTS
1820         bool "Allow interrupts during APM BIOS calls"
1821         ---help---
1822           Normally we disable external interrupts while we are making calls to
1823           the APM BIOS as a measure to lessen the effects of a badly behaving
1824           BIOS implementation.  The BIOS should reenable interrupts if it
1825           needs to.  Unfortunately, some BIOSes do not -- especially those in
1826           many of the newer IBM Thinkpads.  If you experience hangs when you
1827           suspend, try setting this to Y.  Otherwise, say N.
1828
1829 endif # APM
1830
1831 source "drivers/cpufreq/Kconfig"
1832
1833 source "drivers/cpuidle/Kconfig"
1834
1835 source "drivers/idle/Kconfig"
1836
1837 endmenu
1838
1839
1840 menu "Bus options (PCI etc.)"
1841
1842 config PCI
1843         bool "PCI support"
1844         default y
1845         select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1846         ---help---
1847           Find out whether you have a PCI motherboard. PCI is the name of a
1848           bus system, i.e. the way the CPU talks to the other stuff inside
1849           your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1850           VESA. If you have PCI, say Y, otherwise N.
1851
1852 choice
1853         prompt "PCI access mode"
1854         depends on X86_32 && PCI
1855         default PCI_GOANY
1856         ---help---
1857           On PCI systems, the BIOS can be used to detect the PCI devices and
1858           determine their configuration. However, some old PCI motherboards
1859           have BIOS bugs and may crash if this is done. Also, some embedded
1860           PCI-based systems don't have any BIOS at all. Linux can also try to
1861           detect the PCI hardware directly without using the BIOS.
1862
1863           With this option, you can specify how Linux should detect the
1864           PCI devices. If you choose "BIOS", the BIOS will be used,
1865           if you choose "Direct", the BIOS won't be used, and if you
1866           choose "MMConfig", then PCI Express MMCONFIG will be used.
1867           If you choose "Any", the kernel will try MMCONFIG, then the
1868           direct access method and falls back to the BIOS if that doesn't
1869           work. If unsure, go with the default, which is "Any".
1870
1871 config PCI_GOBIOS
1872         bool "BIOS"
1873
1874 config PCI_GOMMCONFIG
1875         bool "MMConfig"
1876
1877 config PCI_GODIRECT
1878         bool "Direct"
1879
1880 config PCI_GOOLPC
1881         bool "OLPC XO-1"
1882         depends on OLPC
1883
1884 config PCI_GOANY
1885         bool "Any"
1886
1887 endchoice
1888
1889 config PCI_BIOS
1890         def_bool y
1891         depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1892
1893 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1894 config PCI_DIRECT
1895         def_bool y
1896         depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1897
1898 config PCI_MMCONFIG
1899         def_bool y
1900         depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
1901
1902 config PCI_OLPC
1903         def_bool y
1904         depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1905
1906 config PCI_XEN
1907         def_bool y
1908         depends on PCI && XEN
1909         select SWIOTLB_XEN
1910
1911 config PCI_DOMAINS
1912         def_bool y
1913         depends on PCI
1914
1915 config PCI_MMCONFIG
1916         bool "Support mmconfig PCI config space access"
1917         depends on X86_64 && PCI && ACPI
1918
1919 config PCI_CNB20LE_QUIRK
1920         bool "Read CNB20LE Host Bridge Windows" if EXPERT
1921         default n
1922         depends on PCI && EXPERIMENTAL
1923         help
1924           Read the PCI windows out of the CNB20LE host bridge. This allows
1925           PCI hotplug to work on systems with the CNB20LE chipset which do
1926           not have ACPI.
1927
1928           There's no public spec for this chipset, and this functionality
1929           is known to be incomplete.
1930
1931           You should say N unless you know you need this.
1932
1933 source "drivers/pci/pcie/Kconfig"
1934
1935 source "drivers/pci/Kconfig"
1936
1937 # x86_64 have no ISA slots, but can have ISA-style DMA.
1938 config ISA_DMA_API
1939         bool "ISA-style DMA support" if (X86_64 && EXPERT)
1940         default y
1941         help
1942           Enables ISA-style DMA support for devices requiring such controllers.
1943           If unsure, say Y.
1944
1945 if X86_32
1946
1947 config ISA
1948         bool "ISA support"
1949         ---help---
1950           Find out whether you have ISA slots on your motherboard.  ISA is the
1951           name of a bus system, i.e. the way the CPU talks to the other stuff
1952           inside your box.  Other bus systems are PCI, EISA, MicroChannel
1953           (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
1954           newer boards don't support it.  If you have ISA, say Y, otherwise N.
1955
1956 config EISA
1957         bool "EISA support"
1958         depends on ISA
1959         ---help---
1960           The Extended Industry Standard Architecture (EISA) bus was
1961           developed as an open alternative to the IBM MicroChannel bus.
1962
1963           The EISA bus provided some of the features of the IBM MicroChannel
1964           bus while maintaining backward compatibility with cards made for
1965           the older ISA bus.  The EISA bus saw limited use between 1988 and
1966           1995 when it was made obsolete by the PCI bus.
1967
1968           Say Y here if you are building a kernel for an EISA-based machine.
1969
1970           Otherwise, say N.
1971
1972 source "drivers/eisa/Kconfig"
1973
1974 config MCA
1975         bool "MCA support"
1976         ---help---
1977           MicroChannel Architecture is found in some IBM PS/2 machines and
1978           laptops.  It is a bus system similar to PCI or ISA. See
1979           <file:Documentation/mca.txt> (and especially the web page given
1980           there) before attempting to build an MCA bus kernel.
1981
1982 source "drivers/mca/Kconfig"
1983
1984 config SCx200
1985         tristate "NatSemi SCx200 support"
1986         ---help---
1987           This provides basic support for National Semiconductor's
1988           (now AMD's) Geode processors.  The driver probes for the
1989           PCI-IDs of several on-chip devices, so its a good dependency
1990           for other scx200_* drivers.
1991
1992           If compiled as a module, the driver is named scx200.
1993
1994 config SCx200HR_TIMER
1995         tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1996         depends on SCx200
1997         default y
1998         ---help---
1999           This driver provides a clocksource built upon the on-chip
2000           27MHz high-resolution timer.  Its also a workaround for
2001           NSC Geode SC-1100's buggy TSC, which loses time when the
2002           processor goes idle (as is done by the scheduler).  The
2003           other workaround is idle=poll boot option.
2004
2005 config OLPC
2006         bool "One Laptop Per Child support"
2007         depends on !X86_PAE
2008         select GPIOLIB
2009         select OF
2010         select OF_PROMTREE
2011         ---help---
2012           Add support for detecting the unique features of the OLPC
2013           XO hardware.
2014
2015 config OLPC_XO1
2016         tristate "OLPC XO-1 support"
2017         depends on OLPC && MFD_CS5535
2018         ---help---
2019           Add support for non-essential features of the OLPC XO-1 laptop.
2020
2021 endif # X86_32
2022
2023 config AMD_NB
2024         def_bool y
2025         depends on CPU_SUP_AMD && PCI
2026
2027 source "drivers/pcmcia/Kconfig"
2028
2029 source "drivers/pci/hotplug/Kconfig"
2030
2031 config RAPIDIO
2032         bool "RapidIO support"
2033         depends on PCI
2034         default n
2035         help
2036           If you say Y here, the kernel will include drivers and
2037           infrastructure code to support RapidIO interconnect devices.
2038
2039 source "drivers/rapidio/Kconfig"
2040
2041 endmenu
2042
2043
2044 menu "Executable file formats / Emulations"
2045
2046 source "fs/Kconfig.binfmt"
2047
2048 config IA32_EMULATION
2049         bool "IA32 Emulation"
2050         depends on X86_64
2051         select COMPAT_BINFMT_ELF
2052         ---help---
2053           Include code to run 32-bit programs under a 64-bit kernel. You should
2054           likely turn this on, unless you're 100% sure that you don't have any
2055           32-bit programs left.
2056
2057 config IA32_AOUT
2058         tristate "IA32 a.out support"
2059         depends on IA32_EMULATION
2060         ---help---
2061           Support old a.out binaries in the 32bit emulation.
2062
2063 config COMPAT
2064         def_bool y
2065         depends on IA32_EMULATION
2066
2067 config COMPAT_FOR_U64_ALIGNMENT
2068         def_bool COMPAT
2069         depends on X86_64
2070
2071 config SYSVIPC_COMPAT
2072         def_bool y
2073         depends on COMPAT && SYSVIPC
2074
2075 config KEYS_COMPAT
2076         bool
2077         depends on COMPAT && KEYS
2078         default y
2079
2080 endmenu
2081
2082
2083 config HAVE_ATOMIC_IOMAP
2084         def_bool y
2085         depends on X86_32
2086
2087 config HAVE_TEXT_POKE_SMP
2088         bool
2089         select STOP_MACHINE if SMP
2090
2091 source "net/Kconfig"
2092
2093 source "drivers/Kconfig"
2094
2095 source "drivers/firmware/Kconfig"
2096
2097 source "fs/Kconfig"
2098
2099 source "arch/x86/Kconfig.debug"
2100
2101 source "security/Kconfig"
2102
2103 source "crypto/Kconfig"
2104
2105 source "arch/x86/kvm/Kconfig"
2106
2107 source "lib/Kconfig"