arch/x86/Kconfig

   1 # x86 configuration
   2 mainmenu "Linux Kernel Configuration for x86"
   3
   4 # Select 32 or 64 bit
   5 config 64BIT
   6         bool "64-bit kernel" if ARCH = "x86"
   7         default ARCH = "x86_64"
   8         ---help---
   9           Say yes to build a 64-bit kernel - formerly known as x86_64
  10           Say no to build a 32-bit kernel - formerly known as i386
  11
  12 config X86_32
  13         def_bool !64BIT
  14
  15 config X86_64
  16         def_bool 64BIT
  17
  18 ### Arch settings
  19 config X86
  20         def_bool y
  21         select HAVE_AOUT if X86_32
  22         select HAVE_READQ
  23         select HAVE_WRITEQ
  24         select HAVE_UNSTABLE_SCHED_CLOCK
  25         select HAVE_IDE
  26         select HAVE_OPROFILE
  27         select HAVE_PERF_EVENTS if (!M386 && !M486)
  28         select HAVE_IRQ_WORK
  29         select HAVE_IOREMAP_PROT
  30         select HAVE_KPROBES
  31         select ARCH_WANT_OPTIONAL_GPIOLIB
  32         select ARCH_WANT_FRAME_POINTERS
  33         select HAVE_DMA_ATTRS
  34         select HAVE_KRETPROBES
  35         select HAVE_OPTPROBES
  36         select HAVE_FTRACE_MCOUNT_RECORD
  37         select HAVE_C_RECORDMCOUNT
  38         select HAVE_DYNAMIC_FTRACE
  39         select HAVE_FUNCTION_TRACER
  40         select HAVE_FUNCTION_GRAPH_TRACER
  41         select HAVE_FUNCTION_GRAPH_FP_TEST
  42         select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  43         select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
  44         select HAVE_SYSCALL_TRACEPOINTS
  45         select HAVE_KVM
  46         select HAVE_ARCH_KGDB
  47         select HAVE_ARCH_TRACEHOOK
  48         select HAVE_GENERIC_DMA_COHERENT if X86_32
  49         select HAVE_EFFICIENT_UNALIGNED_ACCESS
  50         select USER_STACKTRACE_SUPPORT
  51         select HAVE_REGS_AND_STACK_ACCESS_API
  52         select HAVE_DMA_API_DEBUG
  53         select HAVE_KERNEL_GZIP
  54         select HAVE_KERNEL_BZIP2
  55         select HAVE_KERNEL_LZMA
  56         select HAVE_KERNEL_LZO
  57         select HAVE_HW_BREAKPOINT
  58         select HAVE_MIXED_BREAKPOINTS_REGS
  59         select PERF_EVENTS
  60         select HAVE_PERF_EVENTS_NMI
  61         select ANON_INODES
  62         select HAVE_ARCH_KMEMCHECK
  63         select HAVE_USER_RETURN_NOTIFIER
  64         select HAVE_ARCH_JUMP_LABEL
  65         select HAVE_TEXT_POKE_SMP
  66
  67 config INSTRUCTION_DECODER
  68         def_bool (KPROBES || PERF_EVENTS)
  69
  70 config OUTPUT_FORMAT
  71         string
  72         default "elf32-i386" if X86_32
  73         default "elf64-x86-64" if X86_64
  74
  75 config ARCH_DEFCONFIG
  76         string
  77         default "arch/x86/configs/i386_defconfig" if X86_32
  78         default "arch/x86/configs/x86_64_defconfig" if X86_64
  79
  80 config GENERIC_CMOS_UPDATE
  81         def_bool y
  82
  83 config CLOCKSOURCE_WATCHDOG
  84         def_bool y
  85
  86 config GENERIC_CLOCKEVENTS
  87         def_bool y
  88
  89 config GENERIC_CLOCKEVENTS_BROADCAST
  90         def_bool y
  91         depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  92
  93 config LOCKDEP_SUPPORT
  94         def_bool y
  95
  96 config STACKTRACE_SUPPORT
  97         def_bool y
  98
  99 config HAVE_LATENCYTOP_SUPPORT
 100         def_bool y
 101
 102 config MMU
 103         def_bool y
 104
 105 config ZONE_DMA
 106         def_bool y
 107
 108 config SBUS
 109         bool
 110
 111 config NEED_DMA_MAP_STATE
 112        def_bool (X86_64 || DMAR || DMA_API_DEBUG)
 113
 114 config NEED_SG_DMA_LENGTH
 115         def_bool y
 116
 117 config GENERIC_ISA_DMA
 118         def_bool y
 119
 120 config GENERIC_IOMAP
 121         def_bool y
 122
 123 config GENERIC_BUG
 124         def_bool y
 125         depends on BUG
 126         select GENERIC_BUG_RELATIVE_POINTERS if X86_64
 127
 128 config GENERIC_BUG_RELATIVE_POINTERS
 129         bool
 130
 131 config GENERIC_HWEIGHT
 132         def_bool y
 133
 134 config GENERIC_GPIO
 135         bool
 136
 137 config ARCH_MAY_HAVE_PC_FDC
 138         def_bool y
 139
 140 config RWSEM_GENERIC_SPINLOCK
 141         def_bool !X86_XADD
 142
 143 config RWSEM_XCHGADD_ALGORITHM
 144         def_bool X86_XADD
 145
 146 config ARCH_HAS_CPU_IDLE_WAIT
 147         def_bool y
 148
 149 config GENERIC_CALIBRATE_DELAY
 150         def_bool y
 151
 152 config GENERIC_TIME_VSYSCALL
 153         bool
 154         default X86_64
 155
 156 config ARCH_HAS_CPU_RELAX
 157         def_bool y
 158
 159 config ARCH_HAS_DEFAULT_IDLE
 160         def_bool y
 161
 162 config ARCH_HAS_CACHE_LINE_SIZE
 163         def_bool y
 164
 165 config HAVE_SETUP_PER_CPU_AREA
 166         def_bool y
 167
 168 config NEED_PER_CPU_EMBED_FIRST_CHUNK
 169         def_bool y
 170
 171 config NEED_PER_CPU_PAGE_FIRST_CHUNK
 172         def_bool y
 173
 174 config HAVE_CPUMASK_OF_CPU_MAP
 175         def_bool X86_64_SMP
 176
 177 config ARCH_HIBERNATION_POSSIBLE
 178         def_bool y
 179
 180 config ARCH_SUSPEND_POSSIBLE
 181         def_bool y
 182
 183 config ZONE_DMA32
 184         bool
 185         default X86_64
 186
 187 config ARCH_POPULATES_NODE_MAP
 188         def_bool y
 189
 190 config AUDIT_ARCH
 191         bool
 192         default X86_64
 193
 194 config ARCH_SUPPORTS_OPTIMIZED_INLINING
 195         def_bool y
 196
 197 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
 198         def_bool y
 199
 200 config HAVE_EARLY_RES
 201         def_bool y
 202
 203 config HAVE_INTEL_TXT
 204         def_bool y
 205         depends on EXPERIMENTAL && DMAR && ACPI
 206
 207 # Use the generic interrupt handling code in kernel/irq/:
 208 config GENERIC_HARDIRQS
 209         def_bool y
 210
 211 config GENERIC_HARDIRQS_NO__DO_IRQ
 212        def_bool y
 213
 214 config GENERIC_IRQ_PROBE
 215         def_bool y
 216
 217 config GENERIC_PENDING_IRQ
 218         def_bool y
 219         depends on GENERIC_HARDIRQS && SMP
 220
 221 config USE_GENERIC_SMP_HELPERS
 222         def_bool y
 223         depends on SMP
 224
 225 config X86_32_SMP
 226         def_bool y
 227         depends on X86_32 && SMP
 228
 229 config X86_64_SMP
 230         def_bool y
 231         depends on X86_64 && SMP
 232
 233 config X86_HT
 234         def_bool y
 235         depends on SMP
 236
 237 config X86_TRAMPOLINE
 238         def_bool y
 239         depends on SMP || (64BIT && ACPI_SLEEP)
 240
 241 config X86_32_LAZY_GS
 242         def_bool y
 243         depends on X86_32 && !CC_STACKPROTECTOR
 244
 245 config ARCH_HWEIGHT_CFLAGS
 246         string
 247         default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
 248         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
 249
 250 config KTIME_SCALAR
 251         def_bool X86_32
 252
 253 config ARCH_CPU_PROBE_RELEASE
 254         def_bool y
 255         depends on HOTPLUG_CPU
 256
 257 source "init/Kconfig"
 258 source "kernel/Kconfig.freezer"
 259
 260 menu "Processor type and features"
 261
 262 source "kernel/time/Kconfig"
 263
 264 config SMP
 265         bool "Symmetric multi-processing support"
 266         ---help---
 267           This enables support for systems with more than one CPU. If you have
 268           a system with only one CPU, like most personal computers, say N. If
 269           you have a system with more than one CPU, say Y.
 270
 271           If you say N here, the kernel will run on single and multiprocessor
 272           machines, but will use only one CPU of a multiprocessor machine. If
 273           you say Y here, the kernel will run on many, but not all,
 274           singleprocessor machines. On a singleprocessor machine, the kernel
 275           will run faster if you say N here.
 276
 277           Note that if you say Y here and choose architecture "586" or
 278           "Pentium" under "Processor family", the kernel will not work on 486
 279           architectures. Similarly, multiprocessor kernels for the "PPro"
 280           architecture may not work on all Pentium based boards.
 281
 282           People using multiprocessor machines who say Y here should also say
 283           Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
 284           Management" code will be disabled if you say Y here.
 285
 286           See also <file:Documentation/i386/IO-APIC.txt>,
 287           <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
 288           <http://www.tldp.org/docs.html#howto>.
 289
 290           If you don't know what to do here, say N.
 291
 292 config X86_X2APIC
 293         bool "Support x2apic"
 294         depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
 295         ---help---
 296           This enables x2apic support on CPUs that have this feature.
 297
 298           This allows 32-bit apic IDs (so it can support very large systems),
 299           and accesses the local apic via MSRs not via mmio.
 300
 301           If you don't know what to do here, say N.
 302
 303 config SPARSE_IRQ
 304         bool "Support sparse irq numbering"
 305         depends on PCI_MSI || HT_IRQ
 306         ---help---
 307           This enables support for sparse irqs. This is useful for distro
 308           kernels that want to define a high CONFIG_NR_CPUS value but still
 309           want to have low kernel memory footprint on smaller machines.
 310
 311           ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
 312             out the irq_desc[] array in a more NUMA-friendly way. )
 313
 314           If you don't know what to do here, say N.
 315
 316 config NUMA_IRQ_DESC
 317         def_bool y
 318         depends on SPARSE_IRQ && NUMA
 319
 320 config X86_MPPARSE
 321         bool "Enable MPS table" if ACPI
 322         default y
 323         depends on X86_LOCAL_APIC
 324         ---help---
 325           For old smp systems that do not have proper acpi support. Newer systems
 326           (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
 327
 328 config X86_BIGSMP
 329         bool "Support for big SMP systems with more than 8 CPUs"
 330         depends on X86_32 && SMP
 331         ---help---
 332           This option is needed for the systems that have more than 8 CPUs
 333
 334 if X86_32
 335 config X86_EXTENDED_PLATFORM
 336         bool "Support for extended (non-PC) x86 platforms"
 337         default y
 338         ---help---
 339           If you disable this option then the kernel will only support
 340           standard PC platforms. (which covers the vast majority of
 341           systems out there.)
 342
 343           If you enable this option then you'll be able to select support
 344           for the following (non-PC) 32 bit x86 platforms:
 345                 AMD Elan
 346                 NUMAQ (IBM/Sequent)
 347                 RDC R-321x SoC
 348                 SGI 320/540 (Visual Workstation)
 349                 Summit/EXA (IBM x440)
 350                 Unisys ES7000 IA32 series
 351                 Moorestown MID devices
 352
 353           If you have one of these systems, or if you want to build a
 354           generic distribution kernel, say Y here - otherwise say N.
 355 endif
 356
 357 if X86_64
 358 config X86_EXTENDED_PLATFORM
 359         bool "Support for extended (non-PC) x86 platforms"
 360         default y
 361         ---help---
 362           If you disable this option then the kernel will only support
 363           standard PC platforms. (which covers the vast majority of
 364           systems out there.)
 365
 366           If you enable this option then you'll be able to select support
 367           for the following (non-PC) 64 bit x86 platforms:
 368                 ScaleMP vSMP
 369                 SGI Ultraviolet
 370
 371           If you have one of these systems, or if you want to build a
 372           generic distribution kernel, say Y here - otherwise say N.
 373 endif
 374 # This is an alphabetically sorted list of 64 bit extended platforms
 375 # Please maintain the alphabetic order if and when there are additions
 376
 377 config X86_VSMP
 378         bool "ScaleMP vSMP"
 379         select PARAVIRT
 380         depends on X86_64 && PCI
 381         depends on X86_EXTENDED_PLATFORM
 382         ---help---
 383           Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
 384           supposed to run on these EM64T-based machines.  Only choose this option
 385           if you have one of these machines.
 386
 387 config X86_UV
 388         bool "SGI Ultraviolet"
 389         depends on X86_64
 390         depends on X86_EXTENDED_PLATFORM
 391         depends on NUMA
 392         depends on X86_X2APIC
 393         ---help---
 394           This option is needed in order to support SGI Ultraviolet systems.
 395           If you don't have one of these, you should say N here.
 396
 397 # Following is an alphabetically sorted list of 32 bit extended platforms
 398 # Please maintain the alphabetic order if and when there are additions
 399
 400 config X86_ELAN
 401         bool "AMD Elan"
 402         depends on X86_32
 403         depends on X86_EXTENDED_PLATFORM
 404         ---help---
 405           Select this for an AMD Elan processor.
 406
 407           Do not use this option for K6/Athlon/Opteron processors!
 408
 409           If unsure, choose "PC-compatible" instead.
 410
 411 config X86_MRST
 412        bool "Moorestown MID platform"
 413         depends on PCI
 414         depends on PCI_GOANY
 415         depends on X86_32
 416         depends on X86_EXTENDED_PLATFORM
 417         depends on X86_IO_APIC
 418         select APB_TIMER
 419         ---help---
 420           Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
 421           Internet Device(MID) platform. Moorestown consists of two chips:
 422           Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
 423           Unlike standard x86 PCs, Moorestown does not have many legacy devices
 424           nor standard legacy replacement devices/features. e.g. Moorestown does
 425           not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
 426
 427 config X86_RDC321X
 428         bool "RDC R-321x SoC"
 429         depends on X86_32
 430         depends on X86_EXTENDED_PLATFORM
 431         select M486
 432         select X86_REBOOTFIXUPS
 433         ---help---
 434           This option is needed for RDC R-321x system-on-chip, also known
 435           as R-8610-(G).
 436           If you don't have one of these chips, you should say N here.
 437
 438 config X86_32_NON_STANDARD
 439         bool "Support non-standard 32-bit SMP architectures"
 440         depends on X86_32 && SMP
 441         depends on X86_EXTENDED_PLATFORM
 442         ---help---
 443           This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
 444           subarchitectures.  It is intended for a generic binary kernel.
 445           if you select them all, kernel will probe it one by one. and will
 446           fallback to default.
 447
 448 # Alphabetically sorted list of Non standard 32 bit platforms
 449
 450 config X86_NUMAQ
 451         bool "NUMAQ (IBM/Sequent)"
 452         depends on X86_32_NON_STANDARD
 453         depends on PCI
 454         select NUMA
 455         select X86_MPPARSE
 456         ---help---
 457           This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
 458           NUMA multiquad box. This changes the way that processors are
 459           bootstrapped, and uses Clustered Logical APIC addressing mode instead
 460           of Flat Logical.  You will need a new lynxer.elf file to flash your
 461           firmware with - send email to <Martin.Bligh@us.ibm.com>.
 462
 463 config X86_SUPPORTS_MEMORY_FAILURE
 464         def_bool y
 465         # MCE code calls memory_failure():
 466         depends on X86_MCE
 467         # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
 468         depends on !X86_NUMAQ
 469         # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
 470         depends on X86_64 || !SPARSEMEM
 471         select ARCH_SUPPORTS_MEMORY_FAILURE
 472
 473 config X86_VISWS
 474         bool "SGI 320/540 (Visual Workstation)"
 475         depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
 476         depends on X86_32_NON_STANDARD
 477         ---help---
 478           The SGI Visual Workstation series is an IA32-based workstation
 479           based on SGI systems chips with some legacy PC hardware attached.
 480
 481           Say Y here to create a kernel to run on the SGI 320 or 540.
 482
 483           A kernel compiled for the Visual Workstation will run on general
 484           PCs as well. See <file:Documentation/sgi-visws.txt> for details.
 485
 486 config X86_SUMMIT
 487         bool "Summit/EXA (IBM x440)"
 488         depends on X86_32_NON_STANDARD
 489         ---help---
 490           This option is needed for IBM systems that use the Summit/EXA chipset.
 491           In particular, it is needed for the x440.
 492
 493 config X86_ES7000
 494         bool "Unisys ES7000 IA32 series"
 495         depends on X86_32_NON_STANDARD && X86_BIGSMP
 496         ---help---
 497           Support for Unisys ES7000 systems.  Say 'Y' here if this kernel is
 498           supposed to run on an IA32-based Unisys ES7000 system.
 499
 500 config SCHED_OMIT_FRAME_POINTER
 501         def_bool y
 502         prompt "Single-depth WCHAN output"
 503         depends on X86
 504         ---help---
 505           Calculate simpler /proc/<PID>/wchan values. If this option
 506           is disabled then wchan values will recurse back to the
 507           caller function. This provides more accurate wchan values,
 508           at the expense of slightly more scheduling overhead.
 509
 510           If in doubt, say "Y".
 511
 512 menuconfig PARAVIRT_GUEST
 513         bool "Paravirtualized guest support"
 514         ---help---
 515           Say Y here to get to see options related to running Linux under
 516           various hypervisors.  This option alone does not add any kernel code.
 517
 518           If you say N, all options in this submenu will be skipped and disabled.
 519
 520 if PARAVIRT_GUEST
 521
 522 source "arch/x86/xen/Kconfig"
 523
 524 config VMI
 525         bool "VMI Guest support (DEPRECATED)"
 526         select PARAVIRT
 527         depends on X86_32
 528         ---help---
 529           VMI provides a paravirtualized interface to the VMware ESX server
 530           (it could be used by other hypervisors in theory too, but is not
 531           at the moment), by linking the kernel to a GPL-ed ROM module
 532           provided by the hypervisor.
 533
 534           As of September 2009, VMware has started a phased retirement
 535           of this feature from VMware's products. Please see
 536           feature-removal-schedule.txt for details.  If you are
 537           planning to enable this option, please note that you cannot
 538           live migrate a VMI enabled VM to a future VMware product,
 539           which doesn't support VMI. So if you expect your kernel to
 540           seamlessly migrate to newer VMware products, keep this
 541           disabled.
 542
 543 config KVM_CLOCK
 544         bool "KVM paravirtualized clock"
 545         select PARAVIRT
 546         select PARAVIRT_CLOCK
 547         ---help---
 548           Turning on this option will allow you to run a paravirtualized clock
 549           when running over the KVM hypervisor. Instead of relying on a PIT
 550           (or probably other) emulation by the underlying device model, the host
 551           provides the guest with timing infrastructure such as time of day, and
 552           system time
 553
 554 config KVM_GUEST
 555         bool "KVM Guest support"
 556         select PARAVIRT
 557         ---help---
 558           This option enables various optimizations for running under the KVM
 559           hypervisor.
 560
 561 source "arch/x86/lguest/Kconfig"
 562
 563 config PARAVIRT
 564         bool "Enable paravirtualization code"
 565         ---help---
 566           This changes the kernel so it can modify itself when it is run
 567           under a hypervisor, potentially improving performance significantly
 568           over full virtualization.  However, when run without a hypervisor
 569           the kernel is theoretically slower and slightly larger.
 570
 571 config PARAVIRT_SPINLOCKS
 572         bool "Paravirtualization layer for spinlocks"
 573         depends on PARAVIRT && SMP && EXPERIMENTAL
 574         ---help---
 575           Paravirtualized spinlocks allow a pvops backend to replace the
 576           spinlock implementation with something virtualization-friendly
 577           (for example, block the virtual CPU rather than spinning).
 578
 579           Unfortunately the downside is an up to 5% performance hit on
 580           native kernels, with various workloads.
 581
 582           If you are unsure how to answer this question, answer N.
 583
 584 config PARAVIRT_CLOCK
 585         bool
 586
 587 endif
 588
 589 config PARAVIRT_DEBUG
 590         bool "paravirt-ops debugging"
 591         depends on PARAVIRT && DEBUG_KERNEL
 592         ---help---
 593           Enable to debug paravirt_ops internals.  Specifically, BUG if
 594           a paravirt_op is missing when it is called.
 595
 596 config NO_BOOTMEM
 597         default y
 598         bool "Disable Bootmem code"
 599         ---help---
 600           Use early_res directly instead of bootmem before slab is ready.
 601                 - allocator (buddy) [generic]
 602                 - early allocator (bootmem) [generic]
 603                 - very early allocator (reserve_early*()) [x86]
 604                 - very very early allocator (early brk model) [x86]
 605           So reduce one layer between early allocator to final allocator
 606
 607
 608 config MEMTEST
 609         bool "Memtest"
 610         ---help---
 611           This option adds a kernel parameter 'memtest', which allows memtest
 612           to be set.
 613                 memtest=0, mean disabled; -- default
 614                 memtest=1, mean do 1 test pattern;
 615                 ...
 616                 memtest=4, mean do 4 test patterns.
 617           If you are unsure how to answer this question, answer N.
 618
 619 config X86_SUMMIT_NUMA
 620         def_bool y
 621         depends on X86_32 && NUMA && X86_32_NON_STANDARD
 622
 623 config X86_CYCLONE_TIMER
 624         def_bool y
 625         depends on X86_32_NON_STANDARD
 626
 627 source "arch/x86/Kconfig.cpu"
 628
 629 config HPET_TIMER
 630         def_bool X86_64
 631         prompt "HPET Timer Support" if X86_32
 632         ---help---
 633           Use the IA-PC HPET (High Precision Event Timer) to manage
 634           time in preference to the PIT and RTC, if a HPET is
 635           present.
 636           HPET is the next generation timer replacing legacy 8254s.
 637           The HPET provides a stable time base on SMP
 638           systems, unlike the TSC, but it is more expensive to access,
 639           as it is off-chip.  You can find the HPET spec at
 640           <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
 641
 642           You can safely choose Y here.  However, HPET will only be
 643           activated if the platform and the BIOS support this feature.
 644           Otherwise the 8254 will be used for timing services.
 645
 646           Choose N to continue using the legacy 8254 timer.
 647
 648 config HPET_EMULATE_RTC
 649         def_bool y
 650         depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
 651
 652 config APB_TIMER
 653        def_bool y if MRST
 654        prompt "Langwell APB Timer Support" if X86_MRST
 655        help
 656          APB timer is the replacement for 8254, HPET on X86 MID platforms.
 657          The APBT provides a stable time base on SMP
 658          systems, unlike the TSC, but it is more expensive to access,
 659          as it is off-chip. APB timers are always running regardless of CPU
 660          C states, they are used as per CPU clockevent device when possible.
 661
 662 # Mark as embedded because too many people got it wrong.
 663 # The code disables itself when not needed.
 664 config DMI
 665         default y
 666         bool "Enable DMI scanning" if EMBEDDED
 667         ---help---
 668           Enabled scanning of DMI to identify machine quirks. Say Y
 669           here unless you have verified that your setup is not
 670           affected by entries in the DMI blacklist. Required by PNP
 671           BIOS code.
 672
 673 config GART_IOMMU
 674         bool "GART IOMMU support" if EMBEDDED
 675         default y
 676         select SWIOTLB
 677         depends on X86_64 && PCI && K8_NB
 678         ---help---
 679           Support for full DMA access of devices with 32bit memory access only
 680           on systems with more than 3GB. This is usually needed for USB,
 681           sound, many IDE/SATA chipsets and some other devices.
 682           Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
 683           based hardware IOMMU and a software bounce buffer based IOMMU used
 684           on Intel systems and as fallback.
 685           The code is only active when needed (enough memory and limited
 686           device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
 687           too.
 688
 689 config CALGARY_IOMMU
 690         bool "IBM Calgary IOMMU support"
 691         select SWIOTLB
 692         depends on X86_64 && PCI && EXPERIMENTAL
 693         ---help---
 694           Support for hardware IOMMUs in IBM's xSeries x366 and x460
 695           systems. Needed to run systems with more than 3GB of memory
 696           properly with 32-bit PCI devices that do not support DAC
 697           (Double Address Cycle). Calgary also supports bus level
 698           isolation, where all DMAs pass through the IOMMU.  This
 699           prevents them from going anywhere except their intended
 700           destination. This catches hard-to-find kernel bugs and
 701           mis-behaving drivers and devices that do not use the DMA-API
 702           properly to set up their DMA buffers.  The IOMMU can be
 703           turned off at boot time with the iommu=off parameter.
 704           Normally the kernel will make the right choice by itself.
 705           If unsure, say Y.
 706
 707 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
 708         def_bool y
 709         prompt "Should Calgary be enabled by default?"
 710         depends on CALGARY_IOMMU
 711         ---help---
 712           Should Calgary be enabled by default? if you choose 'y', Calgary
 713           will be used (if it exists). If you choose 'n', Calgary will not be
 714           used even if it exists. If you choose 'n' and would like to use
 715           Calgary anyway, pass 'iommu=calgary' on the kernel command line.
 716           If unsure, say Y.
 717
 718 config AMD_IOMMU
 719         bool "AMD IOMMU support"
 720         select SWIOTLB
 721         select PCI_MSI
 722         depends on X86_64 && PCI && ACPI
 723         ---help---
 724           With this option you can enable support for AMD IOMMU hardware in
 725           your system. An IOMMU is a hardware component which provides
 726           remapping of DMA memory accesses from devices. With an AMD IOMMU you
 727           can isolate the the DMA memory of different devices and protect the
 728           system from misbehaving device drivers or hardware.
 729
 730           You can find out if your system has an AMD IOMMU if you look into
 731           your BIOS for an option to enable it or if you have an IVRS ACPI
 732           table.
 733
 734 config AMD_IOMMU_STATS
 735         bool "Export AMD IOMMU statistics to debugfs"
 736         depends on AMD_IOMMU
 737         select DEBUG_FS
 738         ---help---
 739           This option enables code in the AMD IOMMU driver to collect various
 740           statistics about whats happening in the driver and exports that
 741           information to userspace via debugfs.
 742           If unsure, say N.
 743
 744 # need this always selected by IOMMU for the VIA workaround
 745 config SWIOTLB
 746         def_bool y if X86_64
 747         ---help---
 748           Support for software bounce buffers used on x86-64 systems
 749           which don't have a hardware IOMMU (e.g. the current generation
 750           of Intel's x86-64 CPUs). Using this PCI devices which can only
 751           access 32-bits of memory can be used on systems with more than
 752           3 GB of memory. If unsure, say Y.
 753
 754 config IOMMU_HELPER
 755         def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
 756
 757 config IOMMU_API
 758         def_bool (AMD_IOMMU || DMAR)
 759
 760 config MAXSMP
 761         bool "Enable Maximum number of SMP Processors and NUMA Nodes"
 762         depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
 763         select CPUMASK_OFFSTACK
 764         ---help---
 765           Enable maximum number of CPUS and NUMA Nodes for this architecture.
 766           If unsure, say N.
 767
 768 config NR_CPUS
 769         int "Maximum number of CPUs" if SMP && !MAXSMP
 770         range 2 8 if SMP && X86_32 && !X86_BIGSMP
 771         range 2 512 if SMP && !MAXSMP
 772         default "1" if !SMP
 773         default "4096" if MAXSMP
 774         default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
 775         default "8" if SMP
 776         ---help---
 777           This allows you to specify the maximum number of CPUs which this
 778           kernel will support.  The maximum supported value is 512 and the
 779           minimum value which makes sense is 2.
 780
 781           This is purely to save memory - each supported CPU adds
 782           approximately eight kilobytes to the kernel image.
 783
 784 config SCHED_SMT
 785         bool "SMT (Hyperthreading) scheduler support"
 786         depends on X86_HT
 787         ---help---
 788           SMT scheduler support improves the CPU scheduler's decision making
 789           when dealing with Intel Pentium 4 chips with HyperThreading at a
 790           cost of slightly increased overhead in some places. If unsure say
 791           N here.
 792
 793 config SCHED_MC
 794         def_bool y
 795         prompt "Multi-core scheduler support"
 796         depends on X86_HT
 797         ---help---
 798           Multi-core scheduler support improves the CPU scheduler's decision
 799           making when dealing with multi-core CPU chips at a cost of slightly
 800           increased overhead in some places. If unsure say N here.
 801
 802 source "kernel/Kconfig.preempt"
 803
 804 config X86_UP_APIC
 805         bool "Local APIC support on uniprocessors"
 806         depends on X86_32 && !SMP && !X86_32_NON_STANDARD
 807         ---help---
 808           A local APIC (Advanced Programmable Interrupt Controller) is an
 809           integrated interrupt controller in the CPU. If you have a single-CPU
 810           system which has a processor with a local APIC, you can say Y here to
 811           enable and use it. If you say Y here even though your machine doesn't
 812           have a local APIC, then the kernel will still run with no slowdown at
 813           all. The local APIC supports CPU-generated self-interrupts (timer,
 814           performance counters), and the NMI watchdog which detects hard
 815           lockups.
 816
 817 config X86_UP_IOAPIC
 818         bool "IO-APIC support on uniprocessors"
 819         depends on X86_UP_APIC
 820         ---help---
 821           An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
 822           SMP-capable replacement for PC-style interrupt controllers. Most
 823           SMP systems and many recent uniprocessor systems have one.
 824
 825           If you have a single-CPU system with an IO-APIC, you can say Y here
 826           to use it. If you say Y here even though your machine doesn't have
 827           an IO-APIC, then the kernel will still run with no slowdown at all.
 828
 829 config X86_LOCAL_APIC
 830         def_bool y
 831         depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
 832
 833 config X86_IO_APIC
 834         def_bool y
 835         depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
 836
 837 config X86_VISWS_APIC
 838         def_bool y
 839         depends on X86_32 && X86_VISWS
 840
 841 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
 842         bool "Reroute for broken boot IRQs"
 843         depends on X86_IO_APIC
 844         ---help---
 845           This option enables a workaround that fixes a source of
 846           spurious interrupts. This is recommended when threaded
 847           interrupt handling is used on systems where the generation of
 848           superfluous "boot interrupts" cannot be disabled.
 849
 850           Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
 851           entry in the chipset's IO-APIC is masked (as, e.g. the RT
 852           kernel does during interrupt handling). On chipsets where this
 853           boot IRQ generation cannot be disabled, this workaround keeps
 854           the original IRQ line masked so that only the equivalent "boot
 855           IRQ" is delivered to the CPUs. The workaround also tells the
 856           kernel to set up the IRQ handler on the boot IRQ line. In this
 857           way only one interrupt is delivered to the kernel. Otherwise
 858           the spurious second interrupt may cause the kernel to bring
 859           down (vital) interrupt lines.
 860
 861           Only affects "broken" chipsets. Interrupt sharing may be
 862           increased on these systems.
 863
 864 config X86_MCE
 865         bool "Machine Check / overheating reporting"
 866         ---help---
 867           Machine Check support allows the processor to notify the
 868           kernel if it detects a problem (e.g. overheating, data corruption).
 869           The action the kernel takes depends on the severity of the problem,
 870           ranging from warning messages to halting the machine.
 871
 872 config X86_MCE_INTEL
 873         def_bool y
 874         prompt "Intel MCE features"
 875         depends on X86_MCE && X86_LOCAL_APIC
 876         ---help---
 877            Additional support for intel specific MCE features such as
 878            the thermal monitor.
 879
 880 config X86_MCE_AMD
 881         def_bool y
 882         prompt "AMD MCE features"
 883         depends on X86_MCE && X86_LOCAL_APIC
 884         ---help---
 885            Additional support for AMD specific MCE features such as
 886            the DRAM Error Threshold.
 887
 888 config X86_ANCIENT_MCE
 889         bool "Support for old Pentium 5 / WinChip machine checks"
 890         depends on X86_32 && X86_MCE
 891         ---help---
 892           Include support for machine check handling on old Pentium 5 or WinChip
 893           systems. These typically need to be enabled explicitely on the command
 894           line.
 895
 896 config X86_MCE_THRESHOLD
 897         depends on X86_MCE_AMD || X86_MCE_INTEL
 898         def_bool y
 899
 900 config X86_MCE_INJECT
 901         depends on X86_MCE
 902         tristate "Machine check injector support"
 903         ---help---
 904           Provide support for injecting machine checks for testing purposes.
 905           If you don't know what a machine check is and you don't do kernel
 906           QA it is safe to say n.
 907
 908 config X86_THERMAL_VECTOR
 909         def_bool y
 910         depends on X86_MCE_INTEL
 911
 912 config VM86
 913         bool "Enable VM86 support" if EMBEDDED
 914         default y
 915         depends on X86_32
 916         ---help---
 917           This option is required by programs like DOSEMU to run 16-bit legacy
 918           code on X86 processors. It also may be needed by software like
 919           XFree86 to initialize some video cards via BIOS. Disabling this
 920           option saves about 6k.
 921
 922 config TOSHIBA
 923         tristate "Toshiba Laptop support"
 924         depends on X86_32
 925         ---help---
 926           This adds a driver to safely access the System Management Mode of
 927           the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
 928           not work on models with a Phoenix BIOS. The System Management Mode
 929           is used to set the BIOS and power saving options on Toshiba portables.
 930
 931           For information on utilities to make use of this driver see the
 932           Toshiba Linux utilities web site at:
 933           <http://www.buzzard.org.uk/toshiba/>.
 934
 935           Say Y if you intend to run this kernel on a Toshiba portable.
 936           Say N otherwise.
 937
 938 config I8K
 939         tristate "Dell laptop support"
 940         ---help---
 941           This adds a driver to safely access the System Management Mode
 942           of the CPU on the Dell Inspiron 8000. The System Management Mode
 943           is used to read cpu temperature and cooling fan status and to
 944           control the fans on the I8K portables.
 945
 946           This driver has been tested only on the Inspiron 8000 but it may
 947           also work with other Dell laptops. You can force loading on other
 948           models by passing the parameter `force=1' to the module. Use at
 949           your own risk.
 950
 951           For information on utilities to make use of this driver see the
 952           I8K Linux utilities web site at:
 953           <http://people.debian.org/~dz/i8k/>
 954
 955           Say Y if you intend to run this kernel on a Dell Inspiron 8000.
 956           Say N otherwise.
 957
 958 config X86_REBOOTFIXUPS
 959         bool "Enable X86 board specific fixups for reboot"
 960         depends on X86_32
 961         ---help---
 962           This enables chipset and/or board specific fixups to be done
 963           in order to get reboot to work correctly. This is only needed on
 964           some combinations of hardware and BIOS. The symptom, for which
 965           this config is intended, is when reboot ends with a stalled/hung
 966           system.
 967
 968           Currently, the only fixup is for the Geode machines using
 969           CS5530A and CS5536 chipsets and the RDC R-321x SoC.
 970
 971           Say Y if you want to enable the fixup. Currently, it's safe to
 972           enable this option even if you don't need it.
 973           Say N otherwise.
 974
 975 config MICROCODE
 976         tristate "/dev/cpu/microcode - microcode support"
 977         select FW_LOADER
 978         ---help---
 979           If you say Y here, you will be able to update the microcode on
 980           certain Intel and AMD processors. The Intel support is for the
 981           IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
 982           Pentium 4, Xeon etc. The AMD support is for family 0x10 and
 983           0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
 984           You will obviously need the actual microcode binary data itself
 985           which is not shipped with the Linux kernel.
 986
 987           This option selects the general module only, you need to select
 988           at least one vendor specific module as well.
 989
 990           To compile this driver as a module, choose M here: the
 991           module will be called microcode.
 992
 993 config MICROCODE_INTEL
 994         bool "Intel microcode patch loading support"
 995         depends on MICROCODE
 996         default MICROCODE
 997         select FW_LOADER
 998         ---help---
 999           This options enables microcode patch loading support for Intel
1000           processors.
1001
1002           For latest news and information on obtaining all the required
1003           Intel ingredients for this driver, check:
1004           <http://www.urbanmyth.org/microcode/>.
1005
1006 config MICROCODE_AMD
1007         bool "AMD microcode patch loading support"
1008         depends on MICROCODE
1009         select FW_LOADER
1010         ---help---
1011           If you select this option, microcode patch loading support for AMD
1012           processors will be enabled.
1013
1014 config MICROCODE_OLD_INTERFACE
1015         def_bool y
1016         depends on MICROCODE
1017
1018 config X86_MSR
1019         tristate "/dev/cpu/*/msr - Model-specific register support"
1020         ---help---
1021           This device gives privileged processes access to the x86
1022           Model-Specific Registers (MSRs).  It is a character device with
1023           major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1024           MSR accesses are directed to a specific CPU on multi-processor
1025           systems.
1026
1027 config X86_CPUID
1028         tristate "/dev/cpu/*/cpuid - CPU information support"
1029         ---help---
1030           This device gives processes access to the x86 CPUID instruction to
1031           be executed on a specific processor.  It is a character device
1032           with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1033           /dev/cpu/31/cpuid.
1034
1035 choice
1036         prompt "High Memory Support"
1037         default HIGHMEM64G if X86_NUMAQ
1038         default HIGHMEM4G
1039         depends on X86_32
1040
1041 config NOHIGHMEM
1042         bool "off"
1043         depends on !X86_NUMAQ
1044         ---help---
1045           Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1046           However, the address space of 32-bit x86 processors is only 4
1047           Gigabytes large. That means that, if you have a large amount of
1048           physical memory, not all of it can be "permanently mapped" by the
1049           kernel. The physical memory that's not permanently mapped is called
1050           "high memory".
1051
1052           If you are compiling a kernel which will never run on a machine with
1053           more than 1 Gigabyte total physical RAM, answer "off" here (default
1054           choice and suitable for most users). This will result in a "3GB/1GB"
1055           split: 3GB are mapped so that each process sees a 3GB virtual memory
1056           space and the remaining part of the 4GB virtual memory space is used
1057           by the kernel to permanently map as much physical memory as
1058           possible.
1059
1060           If the machine has between 1 and 4 Gigabytes physical RAM, then
1061           answer "4GB" here.
1062
1063           If more than 4 Gigabytes is used then answer "64GB" here. This
1064           selection turns Intel PAE (Physical Address Extension) mode on.
1065           PAE implements 3-level paging on IA32 processors. PAE is fully
1066           supported by Linux, PAE mode is implemented on all recent Intel
1067           processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1068           then the kernel will not boot on CPUs that don't support PAE!
1069
1070           The actual amount of total physical memory will either be
1071           auto detected or can be forced by using a kernel command line option
1072           such as "mem=256M". (Try "man bootparam" or see the documentation of
1073           your boot loader (lilo or loadlin) about how to pass options to the
1074           kernel at boot time.)
1075
1076           If unsure, say "off".
1077
1078 config HIGHMEM4G
1079         bool "4GB"
1080         depends on !X86_NUMAQ
1081         ---help---
1082           Select this if you have a 32-bit processor and between 1 and 4
1083           gigabytes of physical RAM.
1084
1085 config HIGHMEM64G
1086         bool "64GB"
1087         depends on !M386 && !M486
1088         select X86_PAE
1089         ---help---
1090           Select this if you have a 32-bit processor and more than 4
1091           gigabytes of physical RAM.
1092
1093 endchoice
1094
1095 choice
1096         depends on EXPERIMENTAL
1097         prompt "Memory split" if EMBEDDED
1098         default VMSPLIT_3G
1099         depends on X86_32
1100         ---help---
1101           Select the desired split between kernel and user memory.
1102
1103           If the address range available to the kernel is less than the
1104           physical memory installed, the remaining memory will be available
1105           as "high memory". Accessing high memory is a little more costly
1106           than low memory, as it needs to be mapped into the kernel first.
1107           Note that increasing the kernel address space limits the range
1108           available to user programs, making the address space there
1109           tighter.  Selecting anything other than the default 3G/1G split
1110           will also likely make your kernel incompatible with binary-only
1111           kernel modules.
1112
1113           If you are not absolutely sure what you are doing, leave this
1114           option alone!
1115
1116         config VMSPLIT_3G
1117                 bool "3G/1G user/kernel split"
1118         config VMSPLIT_3G_OPT
1119                 depends on !X86_PAE
1120                 bool "3G/1G user/kernel split (for full 1G low memory)"
1121         config VMSPLIT_2G
1122                 bool "2G/2G user/kernel split"
1123         config VMSPLIT_2G_OPT
1124                 depends on !X86_PAE
1125                 bool "2G/2G user/kernel split (for full 2G low memory)"
1126         config VMSPLIT_1G
1127                 bool "1G/3G user/kernel split"
1128 endchoice
1129
1130 config PAGE_OFFSET
1131         hex
1132         default 0xB0000000 if VMSPLIT_3G_OPT
1133         default 0x80000000 if VMSPLIT_2G
1134         default 0x78000000 if VMSPLIT_2G_OPT
1135         default 0x40000000 if VMSPLIT_1G
1136         default 0xC0000000
1137         depends on X86_32
1138
1139 config HIGHMEM
1140         def_bool y
1141         depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1142
1143 config X86_PAE
1144         bool "PAE (Physical Address Extension) Support"
1145         depends on X86_32 && !HIGHMEM4G
1146         ---help---
1147           PAE is required for NX support, and furthermore enables
1148           larger swapspace support for non-overcommit purposes. It
1149           has the cost of more pagetable lookup overhead, and also
1150           consumes more pagetable space per process.
1151
1152 config ARCH_PHYS_ADDR_T_64BIT
1153         def_bool X86_64 || X86_PAE
1154
1155 config DIRECT_GBPAGES
1156         bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
1157         default y
1158         depends on X86_64
1159         ---help---
1160           Allow the kernel linear mapping to use 1GB pages on CPUs that
1161           support it. This can improve the kernel's performance a tiny bit by
1162           reducing TLB pressure. If in doubt, say "Y".
1163
1164 # Common NUMA Features
1165 config NUMA
1166         bool "Numa Memory Allocation and Scheduler Support"
1167         depends on SMP
1168         depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1169         default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1170         ---help---
1171           Enable NUMA (Non Uniform Memory Access) support.
1172
1173           The kernel will try to allocate memory used by a CPU on the
1174           local memory controller of the CPU and add some more
1175           NUMA awareness to the kernel.
1176
1177           For 64-bit this is recommended if the system is Intel Core i7
1178           (or later), AMD Opteron, or EM64T NUMA.
1179
1180           For 32-bit this is only needed on (rare) 32-bit-only platforms
1181           that support NUMA topologies, such as NUMAQ / Summit, or if you
1182           boot a 32-bit kernel on a 64-bit NUMA platform.
1183
1184           Otherwise, you should say N.
1185
1186 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1187         depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1188
1189 config K8_NUMA
1190         def_bool y
1191         prompt "Old style AMD Opteron NUMA detection"
1192         depends on X86_64 && NUMA && PCI
1193         ---help---
1194           Enable K8 NUMA node topology detection.  You should say Y here if
1195           you have a multi processor AMD K8 system. This uses an old
1196           method to read the NUMA configuration directly from the builtin
1197           Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
1198           instead, which also takes priority if both are compiled in.
1199
1200 config X86_64_ACPI_NUMA
1201         def_bool y
1202         prompt "ACPI NUMA detection"
1203         depends on X86_64 && NUMA && ACPI && PCI
1204         select ACPI_NUMA
1205         ---help---
1206           Enable ACPI SRAT based node topology detection.
1207
1208 # Some NUMA nodes have memory ranges that span
1209 # other nodes.  Even though a pfn is valid and
1210 # between a node's start and end pfns, it may not
1211 # reside on that node.  See memmap_init_zone()
1212 # for details.
1213 config NODES_SPAN_OTHER_NODES
1214         def_bool y
1215         depends on X86_64_ACPI_NUMA
1216
1217 config NUMA_EMU
1218         bool "NUMA emulation"
1219         depends on X86_64 && NUMA
1220         ---help---
1221           Enable NUMA emulation. A flat machine will be split
1222           into virtual nodes when booted with "numa=fake=N", where N is the
1223           number of nodes. This is only useful for debugging.
1224
1225 config NODES_SHIFT
1226         int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1227         range 1 10
1228         default "10" if MAXSMP
1229         default "6" if X86_64
1230         default "4" if X86_NUMAQ
1231         default "3"
1232         depends on NEED_MULTIPLE_NODES
1233         ---help---
1234           Specify the maximum number of NUMA Nodes available on the target
1235           system.  Increases memory reserved to accommodate various tables.
1236
1237 config HAVE_ARCH_BOOTMEM
1238         def_bool y
1239         depends on X86_32 && NUMA
1240
1241 config ARCH_HAVE_MEMORY_PRESENT
1242         def_bool y
1243         depends on X86_32 && DISCONTIGMEM
1244
1245 config NEED_NODE_MEMMAP_SIZE
1246         def_bool y
1247         depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1248
1249 config HAVE_ARCH_ALLOC_REMAP
1250         def_bool y
1251         depends on X86_32 && NUMA
1252
1253 config ARCH_FLATMEM_ENABLE
1254         def_bool y
1255         depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
1256
1257 config ARCH_DISCONTIGMEM_ENABLE
1258         def_bool y
1259         depends on NUMA && X86_32
1260
1261 config ARCH_DISCONTIGMEM_DEFAULT
1262         def_bool y
1263         depends on NUMA && X86_32
1264
1265 config ARCH_PROC_KCORE_TEXT
1266         def_bool y
1267         depends on X86_64 && PROC_KCORE
1268
1269 config ARCH_SPARSEMEM_DEFAULT
1270         def_bool y
1271         depends on X86_64
1272
1273 config ARCH_SPARSEMEM_ENABLE
1274         def_bool y
1275         depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1276         select SPARSEMEM_STATIC if X86_32
1277         select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1278
1279 config ARCH_SELECT_MEMORY_MODEL
1280         def_bool y
1281         depends on ARCH_SPARSEMEM_ENABLE
1282
1283 config ARCH_MEMORY_PROBE
1284         def_bool X86_64
1285         depends on MEMORY_HOTPLUG
1286
1287 config ILLEGAL_POINTER_VALUE
1288        hex
1289        default 0 if X86_32
1290        default 0xdead000000000000 if X86_64
1291
1292 source "mm/Kconfig"
1293
1294 config HIGHPTE
1295         bool "Allocate 3rd-level pagetables from highmem"
1296         depends on HIGHMEM
1297         ---help---
1298           The VM uses one page table entry for each page of physical memory.
1299           For systems with a lot of RAM, this can be wasteful of precious
1300           low memory.  Setting this option will put user-space page table
1301           entries in high memory.
1302
1303 config X86_CHECK_BIOS_CORRUPTION
1304         bool "Check for low memory corruption"
1305         ---help---
1306           Periodically check for memory corruption in low memory, which
1307           is suspected to be caused by BIOS.  Even when enabled in the
1308           configuration, it is disabled at runtime.  Enable it by
1309           setting "memory_corruption_check=1" on the kernel command
1310           line.  By default it scans the low 64k of memory every 60
1311           seconds; see the memory_corruption_check_size and
1312           memory_corruption_check_period parameters in
1313           Documentation/kernel-parameters.txt to adjust this.
1314
1315           When enabled with the default parameters, this option has
1316           almost no overhead, as it reserves a relatively small amount
1317           of memory and scans it infrequently.  It both detects corruption
1318           and prevents it from affecting the running system.
1319
1320           It is, however, intended as a diagnostic tool; if repeatable
1321           BIOS-originated corruption always affects the same memory,
1322           you can use memmap= to prevent the kernel from using that
1323           memory.
1324
1325 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1326         bool "Set the default setting of memory_corruption_check"
1327         depends on X86_CHECK_BIOS_CORRUPTION
1328         default y
1329         ---help---
1330           Set whether the default state of memory_corruption_check is
1331           on or off.
1332
1333 config X86_RESERVE_LOW_64K
1334         bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
1335         default y
1336         ---help---
1337           Reserve the first 64K of physical RAM on BIOSes that are known
1338           to potentially corrupt that memory range. A numbers of BIOSes are
1339           known to utilize this area during suspend/resume, so it must not
1340           be used by the kernel.
1341
1342           Set this to N if you are absolutely sure that you trust the BIOS
1343           to get all its memory reservations and usages right.
1344
1345           If you have doubts about the BIOS (e.g. suspend/resume does not
1346           work or there's kernel crashes after certain hardware hotplug
1347           events) and it's not AMI or Phoenix, then you might want to enable
1348           X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
1349           corruption patterns.
1350
1351           Say Y if unsure.
1352
1353 config MATH_EMULATION
1354         bool
1355         prompt "Math emulation" if X86_32
1356         ---help---
1357           Linux can emulate a math coprocessor (used for floating point
1358           operations) if you don't have one. 486DX and Pentium processors have
1359           a math coprocessor built in, 486SX and 386 do not, unless you added
1360           a 487DX or 387, respectively. (The messages during boot time can
1361           give you some hints here ["man dmesg"].) Everyone needs either a
1362           coprocessor or this emulation.
1363
1364           If you don't have a math coprocessor, you need to say Y here; if you
1365           say Y here even though you have a coprocessor, the coprocessor will
1366           be used nevertheless. (This behavior can be changed with the kernel
1367           command line option "no387", which comes handy if your coprocessor
1368           is broken. Try "man bootparam" or see the documentation of your boot
1369           loader (lilo or loadlin) about how to pass options to the kernel at
1370           boot time.) This means that it is a good idea to say Y here if you
1371           intend to use this kernel on different machines.
1372
1373           More information about the internals of the Linux math coprocessor
1374           emulation can be found in <file:arch/x86/math-emu/README>.
1375
1376           If you are not sure, say Y; apart from resulting in a 66 KB bigger
1377           kernel, it won't hurt.
1378
1379 config MTRR
1380         def_bool y
1381         prompt "MTRR (Memory Type Range Register) support" if EMBEDDED
1382         ---help---
1383           On Intel P6 family processors (Pentium Pro, Pentium II and later)
1384           the Memory Type Range Registers (MTRRs) may be used to control
1385           processor access to memory ranges. This is most useful if you have
1386           a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1387           allows bus write transfers to be combined into a larger transfer
1388           before bursting over the PCI/AGP bus. This can increase performance
1389           of image write operations 2.5 times or more. Saying Y here creates a
1390           /proc/mtrr file which may be used to manipulate your processor's
1391           MTRRs. Typically the X server should use this.
1392
1393           This code has a reasonably generic interface so that similar
1394           control registers on other processors can be easily supported
1395           as well:
1396
1397           The Cyrix 6x86, 6x86MX and M II processors have Address Range
1398           Registers (ARRs) which provide a similar functionality to MTRRs. For
1399           these, the ARRs are used to emulate the MTRRs.
1400           The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1401           MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1402           write-combining. All of these processors are supported by this code
1403           and it makes sense to say Y here if you have one of them.
1404
1405           Saying Y here also fixes a problem with buggy SMP BIOSes which only
1406           set the MTRRs for the boot CPU and not for the secondary CPUs. This
1407           can lead to all sorts of problems, so it's good to say Y here.
1408
1409           You can safely say Y even if your machine doesn't have MTRRs, you'll
1410           just add about 9 KB to your kernel.
1411
1412           See <file:Documentation/x86/mtrr.txt> for more information.
1413
1414 config MTRR_SANITIZER
1415         def_bool y
1416         prompt "MTRR cleanup support"
1417         depends on MTRR
1418         ---help---
1419           Convert MTRR layout from continuous to discrete, so X drivers can
1420           add writeback entries.
1421
1422           Can be disabled with disable_mtrr_cleanup on the kernel command line.
1423           The largest mtrr entry size for a continuous block can be set with
1424           mtrr_chunk_size.
1425
1426           If unsure, say Y.
1427
1428 config MTRR_SANITIZER_ENABLE_DEFAULT
1429         int "MTRR cleanup enable value (0-1)"
1430         range 0 1
1431         default "0"
1432         depends on MTRR_SANITIZER
1433         ---help---
1434           Enable mtrr cleanup default value
1435
1436 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1437         int "MTRR cleanup spare reg num (0-7)"
1438         range 0 7
1439         default "1"
1440         depends on MTRR_SANITIZER
1441         ---help---
1442           mtrr cleanup spare entries default, it can be changed via
1443           mtrr_spare_reg_nr=N on the kernel command line.
1444
1445 config X86_PAT
1446         def_bool y
1447         prompt "x86 PAT support" if EMBEDDED
1448         depends on MTRR
1449         ---help---
1450           Use PAT attributes to setup page level cache control.
1451
1452           PATs are the modern equivalents of MTRRs and are much more
1453           flexible than MTRRs.
1454
1455           Say N here if you see bootup problems (boot crash, boot hang,
1456           spontaneous reboots) or a non-working video driver.
1457
1458           If unsure, say Y.
1459
1460 config ARCH_USES_PG_UNCACHED
1461         def_bool y
1462         depends on X86_PAT
1463
1464 config EFI
1465         bool "EFI runtime service support"
1466         depends on ACPI
1467         ---help---
1468           This enables the kernel to use EFI runtime services that are
1469           available (such as the EFI variable services).
1470
1471           This option is only useful on systems that have EFI firmware.
1472           In addition, you should use the latest ELILO loader available
1473           at <http://elilo.sourceforge.net> in order to take advantage
1474           of EFI runtime services. However, even with this option, the
1475           resultant kernel should continue to boot on existing non-EFI
1476           platforms.
1477
1478 config SECCOMP
1479         def_bool y
1480         prompt "Enable seccomp to safely compute untrusted bytecode"
1481         ---help---
1482           This kernel feature is useful for number crunching applications
1483           that may need to compute untrusted bytecode during their
1484           execution. By using pipes or other transports made available to
1485           the process as file descriptors supporting the read/write
1486           syscalls, it's possible to isolate those applications in
1487           their own address space using seccomp. Once seccomp is
1488           enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1489           and the task is only allowed to execute a few safe syscalls
1490           defined by each seccomp mode.
1491
1492           If unsure, say Y. Only embedded should say N here.
1493
1494 config CC_STACKPROTECTOR
1495         bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1496         ---help---
1497           This option turns on the -fstack-protector GCC feature. This
1498           feature puts, at the beginning of functions, a canary value on
1499           the stack just before the return address, and validates
1500           the value just before actually returning.  Stack based buffer
1501           overflows (that need to overwrite this return address) now also
1502           overwrite the canary, which gets detected and the attack is then
1503           neutralized via a kernel panic.
1504
1505           This feature requires gcc version 4.2 or above, or a distribution
1506           gcc with the feature backported. Older versions are automatically
1507           detected and for those versions, this configuration option is
1508           ignored. (and a warning is printed during bootup)
1509
1510 source kernel/Kconfig.hz
1511
1512 config KEXEC
1513         bool "kexec system call"
1514         ---help---
1515           kexec is a system call that implements the ability to shutdown your
1516           current kernel, and to start another kernel.  It is like a reboot
1517           but it is independent of the system firmware.   And like a reboot
1518           you can start any kernel with it, not just Linux.
1519
1520           The name comes from the similarity to the exec system call.
1521
1522           It is an ongoing process to be certain the hardware in a machine
1523           is properly shutdown, so do not be surprised if this code does not
1524           initially work for you.  It may help to enable device hotplugging
1525           support.  As of this writing the exact hardware interface is
1526           strongly in flux, so no good recommendation can be made.
1527
1528 config CRASH_DUMP
1529         bool "kernel crash dumps"
1530         depends on X86_64 || (X86_32 && HIGHMEM)
1531         ---help---
1532           Generate crash dump after being started by kexec.
1533           This should be normally only set in special crash dump kernels
1534           which are loaded in the main kernel with kexec-tools into
1535           a specially reserved region and then later executed after
1536           a crash by kdump/kexec. The crash dump kernel must be compiled
1537           to a memory address not used by the main kernel or BIOS using
1538           PHYSICAL_START, or it must be built as a relocatable image
1539           (CONFIG_RELOCATABLE=y).
1540           For more details see Documentation/kdump/kdump.txt
1541
1542 config KEXEC_JUMP
1543         bool "kexec jump (EXPERIMENTAL)"
1544         depends on EXPERIMENTAL
1545         depends on KEXEC && HIBERNATION
1546         ---help---
1547           Jump between original kernel and kexeced kernel and invoke
1548           code in physical address mode via KEXEC
1549
1550 config PHYSICAL_START
1551         hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1552         default "0x1000000"
1553         ---help---
1554           This gives the physical address where the kernel is loaded.
1555
1556           If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1557           bzImage will decompress itself to above physical address and
1558           run from there. Otherwise, bzImage will run from the address where
1559           it has been loaded by the boot loader and will ignore above physical
1560           address.
1561
1562           In normal kdump cases one does not have to set/change this option
1563           as now bzImage can be compiled as a completely relocatable image
1564           (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1565           address. This option is mainly useful for the folks who don't want
1566           to use a bzImage for capturing the crash dump and want to use a
1567           vmlinux instead. vmlinux is not relocatable hence a kernel needs
1568           to be specifically compiled to run from a specific memory area
1569           (normally a reserved region) and this option comes handy.
1570
1571           So if you are using bzImage for capturing the crash dump,
1572           leave the value here unchanged to 0x1000000 and set
1573           CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
1574           for capturing the crash dump change this value to start of
1575           the reserved region.  In other words, it can be set based on
1576           the "X" value as specified in the "crashkernel=YM@XM"
1577           command line boot parameter passed to the panic-ed
1578           kernel. Please take a look at Documentation/kdump/kdump.txt
1579           for more details about crash dumps.
1580
1581           Usage of bzImage for capturing the crash dump is recommended as
1582           one does not have to build two kernels. Same kernel can be used
1583           as production kernel and capture kernel. Above option should have
1584           gone away after relocatable bzImage support is introduced. But it
1585           is present because there are users out there who continue to use
1586           vmlinux for dump capture. This option should go away down the
1587           line.
1588
1589           Don't change this unless you know what you are doing.
1590
1591 config RELOCATABLE
1592         bool "Build a relocatable kernel"
1593         default y
1594         ---help---
1595           This builds a kernel image that retains relocation information
1596           so it can be loaded someplace besides the default 1MB.
1597           The relocations tend to make the kernel binary about 10% larger,
1598           but are discarded at runtime.
1599
1600           One use is for the kexec on panic case where the recovery kernel
1601           must live at a different physical address than the primary
1602           kernel.
1603
1604           Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1605           it has been loaded at and the compile time physical address
1606           (CONFIG_PHYSICAL_START) is ignored.
1607
1608 # Relocation on x86-32 needs some additional build support
1609 config X86_NEED_RELOCS
1610         def_bool y
1611         depends on X86_32 && RELOCATABLE
1612
1613 config PHYSICAL_ALIGN
1614         hex "Alignment value to which kernel should be aligned" if X86_32
1615         default "0x1000000"
1616         range 0x2000 0x1000000
1617         ---help---
1618           This value puts the alignment restrictions on physical address
1619           where kernel is loaded and run from. Kernel is compiled for an
1620           address which meets above alignment restriction.
1621
1622           If bootloader loads the kernel at a non-aligned address and
1623           CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1624           address aligned to above value and run from there.
1625
1626           If bootloader loads the kernel at a non-aligned address and
1627           CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1628           load address and decompress itself to the address it has been
1629           compiled for and run from there. The address for which kernel is
1630           compiled already meets above alignment restrictions. Hence the
1631           end result is that kernel runs from a physical address meeting
1632           above alignment restrictions.
1633
1634           Don't change this unless you know what you are doing.
1635
1636 config HOTPLUG_CPU
1637         bool "Support for hot-pluggable CPUs"
1638         depends on SMP && HOTPLUG
1639         ---help---
1640           Say Y here to allow turning CPUs off and on. CPUs can be
1641           controlled through /sys/devices/system/cpu.
1642           ( Note: power management support will enable this option
1643             automatically on SMP systems. )
1644           Say N if you want to disable CPU hotplug.
1645
1646 config COMPAT_VDSO
1647         def_bool y
1648         prompt "Compat VDSO support"
1649         depends on X86_32 || IA32_EMULATION
1650         ---help---
1651           Map the 32-bit VDSO to the predictable old-style address too.
1652
1653           Say N here if you are running a sufficiently recent glibc
1654           version (2.3.3 or later), to remove the high-mapped
1655           VDSO mapping and to exclusively use the randomized VDSO.
1656
1657           If unsure, say Y.
1658
1659 config CMDLINE_BOOL
1660         bool "Built-in kernel command line"
1661         ---help---
1662           Allow for specifying boot arguments to the kernel at
1663           build time.  On some systems (e.g. embedded ones), it is
1664           necessary or convenient to provide some or all of the
1665           kernel boot arguments with the kernel itself (that is,
1666           to not rely on the boot loader to provide them.)
1667
1668           To compile command line arguments into the kernel,
1669           set this option to 'Y', then fill in the
1670           the boot arguments in CONFIG_CMDLINE.
1671
1672           Systems with fully functional boot loaders (i.e. non-embedded)
1673           should leave this option set to 'N'.
1674
1675 config CMDLINE
1676         string "Built-in kernel command string"
1677         depends on CMDLINE_BOOL
1678         default ""
1679         ---help---
1680           Enter arguments here that should be compiled into the kernel
1681           image and used at boot time.  If the boot loader provides a
1682           command line at boot time, it is appended to this string to
1683           form the full kernel command line, when the system boots.
1684
1685           However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1686           change this behavior.
1687
1688           In most cases, the command line (whether built-in or provided
1689           by the boot loader) should specify the device for the root
1690           file system.
1691
1692 config CMDLINE_OVERRIDE
1693         bool "Built-in command line overrides boot loader arguments"
1694         depends on CMDLINE_BOOL
1695         ---help---
1696           Set this option to 'Y' to have the kernel ignore the boot loader
1697           command line, and use ONLY the built-in command line.
1698
1699           This is used to work around broken boot loaders.  This should
1700           be set to 'N' under normal conditions.
1701
1702 endmenu
1703
1704 config ARCH_ENABLE_MEMORY_HOTPLUG
1705         def_bool y
1706         depends on X86_64 || (X86_32 && HIGHMEM)
1707
1708 config ARCH_ENABLE_MEMORY_HOTREMOVE
1709         def_bool y
1710         depends on MEMORY_HOTPLUG
1711
1712 config HAVE_ARCH_EARLY_PFN_TO_NID
1713         def_bool X86_64
1714         depends on NUMA
1715
1716 config USE_PERCPU_NUMA_NODE_ID
1717         def_bool X86_64
1718         depends on NUMA
1719
1720 menu "Power management and ACPI options"
1721
1722 config ARCH_HIBERNATION_HEADER
1723         def_bool y
1724         depends on X86_64 && HIBERNATION
1725
1726 source "kernel/power/Kconfig"
1727
1728 source "drivers/acpi/Kconfig"
1729
1730 source "drivers/sfi/Kconfig"
1731
1732 config X86_APM_BOOT
1733         def_bool y
1734         depends on APM || APM_MODULE
1735
1736 menuconfig APM
1737         tristate "APM (Advanced Power Management) BIOS support"
1738         depends on X86_32 && PM_SLEEP
1739         ---help---
1740           APM is a BIOS specification for saving power using several different
1741           techniques. This is mostly useful for battery powered laptops with
1742           APM compliant BIOSes. If you say Y here, the system time will be
1743           reset after a RESUME operation, the /proc/apm device will provide
1744           battery status information, and user-space programs will receive
1745           notification of APM "events" (e.g. battery status change).
1746
1747           If you select "Y" here, you can disable actual use of the APM
1748           BIOS by passing the "apm=off" option to the kernel at boot time.
1749
1750           Note that the APM support is almost completely disabled for
1751           machines with more than one CPU.
1752
1753           In order to use APM, you will need supporting software. For location
1754           and more information, read <file:Documentation/power/pm.txt> and the
1755           Battery Powered Linux mini-HOWTO, available from
1756           <http://www.tldp.org/docs.html#howto>.
1757
1758           This driver does not spin down disk drives (see the hdparm(8)
1759           manpage ("man 8 hdparm") for that), and it doesn't turn off
1760           VESA-compliant "green" monitors.
1761
1762           This driver does not support the TI 4000M TravelMate and the ACER
1763           486/DX4/75 because they don't have compliant BIOSes. Many "green"
1764           desktop machines also don't have compliant BIOSes, and this driver
1765           may cause those machines to panic during the boot phase.
1766
1767           Generally, if you don't have a battery in your machine, there isn't
1768           much point in using this driver and you should say N. If you get
1769           random kernel OOPSes or reboots that don't seem to be related to
1770           anything, try disabling/enabling this option (or disabling/enabling
1771           APM in your BIOS).
1772
1773           Some other things you should try when experiencing seemingly random,
1774           "weird" problems:
1775
1776           1) make sure that you have enough swap space and that it is
1777           enabled.
1778           2) pass the "no-hlt" option to the kernel
1779           3) switch on floating point emulation in the kernel and pass
1780           the "no387" option to the kernel
1781           4) pass the "floppy=nodma" option to the kernel
1782           5) pass the "mem=4M" option to the kernel (thereby disabling
1783           all but the first 4 MB of RAM)
1784           6) make sure that the CPU is not over clocked.
1785           7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1786           8) disable the cache from your BIOS settings
1787           9) install a fan for the video card or exchange video RAM
1788           10) install a better fan for the CPU
1789           11) exchange RAM chips
1790           12) exchange the motherboard.
1791
1792           To compile this driver as a module, choose M here: the
1793           module will be called apm.
1794
1795 if APM
1796
1797 config APM_IGNORE_USER_SUSPEND
1798         bool "Ignore USER SUSPEND"
1799         ---help---
1800           This option will ignore USER SUSPEND requests. On machines with a
1801           compliant APM BIOS, you want to say N. However, on the NEC Versa M
1802           series notebooks, it is necessary to say Y because of a BIOS bug.
1803
1804 config APM_DO_ENABLE
1805         bool "Enable PM at boot time"
1806         ---help---
1807           Enable APM features at boot time. From page 36 of the APM BIOS
1808           specification: "When disabled, the APM BIOS does not automatically
1809           power manage devices, enter the Standby State, enter the Suspend
1810           State, or take power saving steps in response to CPU Idle calls."
1811           This driver will make CPU Idle calls when Linux is idle (unless this
1812           feature is turned off -- see "Do CPU IDLE calls", below). This
1813           should always save battery power, but more complicated APM features
1814           will be dependent on your BIOS implementation. You may need to turn
1815           this option off if your computer hangs at boot time when using APM
1816           support, or if it beeps continuously instead of suspending. Turn
1817           this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1818           T400CDT. This is off by default since most machines do fine without
1819           this feature.
1820
1821 config APM_CPU_IDLE
1822         bool "Make CPU Idle calls when idle"
1823         ---help---
1824           Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1825           On some machines, this can activate improved power savings, such as
1826           a slowed CPU clock rate, when the machine is idle. These idle calls
1827           are made after the idle loop has run for some length of time (e.g.,
1828           333 mS). On some machines, this will cause a hang at boot time or
1829           whenever the CPU becomes idle. (On machines with more than one CPU,
1830           this option does nothing.)
1831
1832 config APM_DISPLAY_BLANK
1833         bool "Enable console blanking using APM"
1834         ---help---
1835           Enable console blanking using the APM. Some laptops can use this to
1836           turn off the LCD backlight when the screen blanker of the Linux
1837           virtual console blanks the screen. Note that this is only used by
1838           the virtual console screen blanker, and won't turn off the backlight
1839           when using the X Window system. This also doesn't have anything to
1840           do with your VESA-compliant power-saving monitor. Further, this
1841           option doesn't work for all laptops -- it might not turn off your
1842           backlight at all, or it might print a lot of errors to the console,
1843           especially if you are using gpm.
1844
1845 config APM_ALLOW_INTS
1846         bool "Allow interrupts during APM BIOS calls"
1847         ---help---
1848           Normally we disable external interrupts while we are making calls to
1849           the APM BIOS as a measure to lessen the effects of a badly behaving
1850           BIOS implementation.  The BIOS should reenable interrupts if it
1851           needs to.  Unfortunately, some BIOSes do not -- especially those in
1852           many of the newer IBM Thinkpads.  If you experience hangs when you
1853           suspend, try setting this to Y.  Otherwise, say N.
1854
1855 endif # APM
1856
1857 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1858
1859 source "drivers/cpuidle/Kconfig"
1860
1861 source "drivers/idle/Kconfig"
1862
1863 endmenu
1864
1865
1866 menu "Bus options (PCI etc.)"
1867
1868 config PCI
1869         bool "PCI support"
1870         default y
1871         select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1872         ---help---
1873           Find out whether you have a PCI motherboard. PCI is the name of a
1874           bus system, i.e. the way the CPU talks to the other stuff inside
1875           your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1876           VESA. If you have PCI, say Y, otherwise N.
1877
1878 choice
1879         prompt "PCI access mode"
1880         depends on X86_32 && PCI
1881         default PCI_GOANY
1882         ---help---
1883           On PCI systems, the BIOS can be used to detect the PCI devices and
1884           determine their configuration. However, some old PCI motherboards
1885           have BIOS bugs and may crash if this is done. Also, some embedded
1886           PCI-based systems don't have any BIOS at all. Linux can also try to
1887           detect the PCI hardware directly without using the BIOS.
1888
1889           With this option, you can specify how Linux should detect the
1890           PCI devices. If you choose "BIOS", the BIOS will be used,
1891           if you choose "Direct", the BIOS won't be used, and if you
1892           choose "MMConfig", then PCI Express MMCONFIG will be used.
1893           If you choose "Any", the kernel will try MMCONFIG, then the
1894           direct access method and falls back to the BIOS if that doesn't
1895           work. If unsure, go with the default, which is "Any".
1896
1897 config PCI_GOBIOS
1898         bool "BIOS"
1899
1900 config PCI_GOMMCONFIG
1901         bool "MMConfig"
1902
1903 config PCI_GODIRECT
1904         bool "Direct"
1905
1906 config PCI_GOOLPC
1907         bool "OLPC"
1908         depends on OLPC
1909
1910 config PCI_GOANY
1911         bool "Any"
1912
1913 endchoice
1914
1915 config PCI_BIOS
1916         def_bool y
1917         depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1918
1919 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1920 config PCI_DIRECT
1921         def_bool y
1922         depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1923
1924 config PCI_MMCONFIG
1925         def_bool y
1926         depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
1927
1928 config PCI_OLPC
1929         def_bool y
1930         depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1931
1932 config PCI_DOMAINS
1933         def_bool y
1934         depends on PCI
1935
1936 config PCI_MMCONFIG
1937         bool "Support mmconfig PCI config space access"
1938         depends on X86_64 && PCI && ACPI
1939
1940 config PCI_CNB20LE_QUIRK
1941         bool "Read CNB20LE Host Bridge Windows"
1942         depends on PCI
1943         help
1944           Read the PCI windows out of the CNB20LE host bridge. This allows
1945           PCI hotplug to work on systems with the CNB20LE chipset which do
1946           not have ACPI.
1947
1948 config DMAR
1949         bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1950         depends on PCI_MSI && ACPI && EXPERIMENTAL
1951         help
1952           DMA remapping (DMAR) devices support enables independent address
1953           translations for Direct Memory Access (DMA) from devices.
1954           These DMA remapping devices are reported via ACPI tables
1955           and include PCI device scope covered by these DMA
1956           remapping devices.
1957
1958 config DMAR_DEFAULT_ON
1959         def_bool y
1960         prompt "Enable DMA Remapping Devices by default"
1961         depends on DMAR
1962         help
1963           Selecting this option will enable a DMAR device at boot time if
1964           one is found. If this option is not selected, DMAR support can
1965           be enabled by passing intel_iommu=on to the kernel. It is
1966           recommended you say N here while the DMAR code remains
1967           experimental.
1968
1969 config DMAR_BROKEN_GFX_WA
1970         bool "Workaround broken graphics drivers (going away soon)"
1971         depends on DMAR && BROKEN
1972         ---help---
1973           Current Graphics drivers tend to use physical address
1974           for DMA and avoid using DMA APIs. Setting this config
1975           option permits the IOMMU driver to set a unity map for
1976           all the OS-visible memory. Hence the driver can continue
1977           to use physical addresses for DMA, at least until this
1978           option is removed in the 2.6.32 kernel.
1979
1980 config DMAR_FLOPPY_WA
1981         def_bool y
1982         depends on DMAR
1983         ---help---
1984           Floppy disk drivers are known to bypass DMA API calls
1985           thereby failing to work when IOMMU is enabled. This
1986           workaround will setup a 1:1 mapping for the first
1987           16MiB to make floppy (an ISA device) work.
1988
1989 config INTR_REMAP
1990         bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1991         depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
1992         ---help---
1993           Supports Interrupt remapping for IO-APIC and MSI devices.
1994           To use x2apic mode in the CPU's which support x2APIC enhancements or
1995           to support platforms with CPU's having > 8 bit APIC ID, say Y.
1996
1997 source "drivers/pci/pcie/Kconfig"
1998
1999 source "drivers/pci/Kconfig"
2000
2001 # x86_64 have no ISA slots, but do have ISA-style DMA.
2002 config ISA_DMA_API
2003         def_bool y
2004
2005 if X86_32
2006
2007 config ISA
2008         bool "ISA support"
2009         ---help---
2010           Find out whether you have ISA slots on your motherboard.  ISA is the
2011           name of a bus system, i.e. the way the CPU talks to the other stuff
2012           inside your box.  Other bus systems are PCI, EISA, MicroChannel
2013           (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
2014           newer boards don't support it.  If you have ISA, say Y, otherwise N.
2015
2016 config EISA
2017         bool "EISA support"
2018         depends on ISA
2019         ---help---
2020           The Extended Industry Standard Architecture (EISA) bus was
2021           developed as an open alternative to the IBM MicroChannel bus.
2022
2023           The EISA bus provided some of the features of the IBM MicroChannel
2024           bus while maintaining backward compatibility with cards made for
2025           the older ISA bus.  The EISA bus saw limited use between 1988 and
2026           1995 when it was made obsolete by the PCI bus.
2027
2028           Say Y here if you are building a kernel for an EISA-based machine.
2029
2030           Otherwise, say N.
2031
2032 source "drivers/eisa/Kconfig"
2033
2034 config MCA
2035         bool "MCA support"
2036         ---help---
2037           MicroChannel Architecture is found in some IBM PS/2 machines and
2038           laptops.  It is a bus system similar to PCI or ISA. See
2039           <file:Documentation/mca.txt> (and especially the web page given
2040           there) before attempting to build an MCA bus kernel.
2041
2042 source "drivers/mca/Kconfig"
2043
2044 config SCx200
2045         tristate "NatSemi SCx200 support"
2046         ---help---
2047           This provides basic support for National Semiconductor's
2048           (now AMD's) Geode processors.  The driver probes for the
2049           PCI-IDs of several on-chip devices, so its a good dependency
2050           for other scx200_* drivers.
2051
2052           If compiled as a module, the driver is named scx200.
2053
2054 config SCx200HR_TIMER
2055         tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2056         depends on SCx200
2057         default y
2058         ---help---
2059           This driver provides a clocksource built upon the on-chip
2060           27MHz high-resolution timer.  Its also a workaround for
2061           NSC Geode SC-1100's buggy TSC, which loses time when the
2062           processor goes idle (as is done by the scheduler).  The
2063           other workaround is idle=poll boot option.
2064
2065 config OLPC
2066         bool "One Laptop Per Child support"
2067         select GPIOLIB
2068         ---help---
2069           Add support for detecting the unique features of the OLPC
2070           XO hardware.
2071
2072 config OLPC_OPENFIRMWARE
2073         bool "Support for OLPC's Open Firmware"
2074         depends on !X86_64 && !X86_PAE
2075         default y if OLPC
2076         help
2077           This option adds support for the implementation of Open Firmware
2078           that is used on the OLPC XO-1 Children's Machine.
2079           If unsure, say N here.
2080
2081 endif # X86_32
2082
2083 config K8_NB
2084         def_bool y
2085         depends on CPU_SUP_AMD && PCI
2086
2087 source "drivers/pcmcia/Kconfig"
2088
2089 source "drivers/pci/hotplug/Kconfig"
2090
2091 endmenu
2092
2093
2094 menu "Executable file formats / Emulations"
2095
2096 source "fs/Kconfig.binfmt"
2097
2098 config IA32_EMULATION
2099         bool "IA32 Emulation"
2100         depends on X86_64
2101         select COMPAT_BINFMT_ELF
2102         ---help---
2103           Include code to run 32-bit programs under a 64-bit kernel. You should
2104           likely turn this on, unless you're 100% sure that you don't have any
2105           32-bit programs left.
2106
2107 config IA32_AOUT
2108         tristate "IA32 a.out support"
2109         depends on IA32_EMULATION
2110         ---help---
2111           Support old a.out binaries in the 32bit emulation.
2112
2113 config COMPAT
2114         def_bool y
2115         depends on IA32_EMULATION
2116
2117 config COMPAT_FOR_U64_ALIGNMENT
2118         def_bool COMPAT
2119         depends on X86_64
2120
2121 config SYSVIPC_COMPAT
2122         def_bool y
2123         depends on COMPAT && SYSVIPC
2124
2125 endmenu
2126
2127
2128 config HAVE_ATOMIC_IOMAP
2129         def_bool y
2130         depends on X86_32
2131
2132 config HAVE_TEXT_POKE_SMP
2133         bool
2134         select STOP_MACHINE if SMP
2135
2136 source "net/Kconfig"
2137
2138 source "drivers/Kconfig"
2139
2140 source "drivers/firmware/Kconfig"
2141
2142 source "fs/Kconfig"
2143
2144 source "arch/x86/Kconfig.debug"
2145
2146 source "security/Kconfig"
2147
2148 source "crypto/Kconfig"
2149
2150 source "arch/x86/kvm/Kconfig"
2151
2152 source "lib/Kconfig"