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_COUNTERS if (!M386 && !M486)
  28         select HAVE_IOREMAP_PROT
  29         select HAVE_KPROBES
  30         select ARCH_WANT_OPTIONAL_GPIOLIB
  31         select ARCH_WANT_FRAME_POINTERS
  32         select HAVE_DMA_ATTRS
  33         select HAVE_KRETPROBES
  34         select HAVE_FTRACE_MCOUNT_RECORD
  35         select HAVE_DYNAMIC_FTRACE
  36         select HAVE_FUNCTION_TRACER
  37         select HAVE_FUNCTION_GRAPH_TRACER
  38         select HAVE_FUNCTION_GRAPH_FP_TEST
  39         select HAVE_FUNCTION_TRACE_MCOUNT_TEST
  40         select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
  41         select HAVE_SYSCALL_TRACEPOINTS
  42         select HAVE_KVM
  43         select HAVE_ARCH_KGDB
  44         select HAVE_ARCH_TRACEHOOK
  45         select HAVE_GENERIC_DMA_COHERENT if X86_32
  46         select HAVE_EFFICIENT_UNALIGNED_ACCESS
  47         select USER_STACKTRACE_SUPPORT
  48         select HAVE_DMA_API_DEBUG
  49         select HAVE_KERNEL_GZIP
  50         select HAVE_KERNEL_BZIP2
  51         select HAVE_KERNEL_LZMA
  52         select HAVE_HW_BREAKPOINT
  53         select HAVE_ARCH_KMEMCHECK
  54
  55 config OUTPUT_FORMAT
  56         string
  57         default "elf32-i386" if X86_32
  58         default "elf64-x86-64" if X86_64
  59
  60 config ARCH_DEFCONFIG
  61         string
  62         default "arch/x86/configs/i386_defconfig" if X86_32
  63         default "arch/x86/configs/x86_64_defconfig" if X86_64
  64
  65 config GENERIC_TIME
  66         def_bool y
  67
  68 config GENERIC_CMOS_UPDATE
  69         def_bool y
  70
  71 config CLOCKSOURCE_WATCHDOG
  72         def_bool y
  73
  74 config GENERIC_CLOCKEVENTS
  75         def_bool y
  76
  77 config GENERIC_CLOCKEVENTS_BROADCAST
  78         def_bool y
  79         depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
  80
  81 config LOCKDEP_SUPPORT
  82         def_bool y
  83
  84 config STACKTRACE_SUPPORT
  85         def_bool y
  86
  87 config HAVE_LATENCYTOP_SUPPORT
  88         def_bool y
  89
  90 config FAST_CMPXCHG_LOCAL
  91         bool
  92         default y
  93
  94 config MMU
  95         def_bool y
  96
  97 config ZONE_DMA
  98         def_bool y
  99
 100 config SBUS
 101         bool
 102
 103 config GENERIC_ISA_DMA
 104         def_bool y
 105
 106 config GENERIC_IOMAP
 107         def_bool y
 108
 109 config GENERIC_BUG
 110         def_bool y
 111         depends on BUG
 112         select GENERIC_BUG_RELATIVE_POINTERS if X86_64
 113
 114 config GENERIC_BUG_RELATIVE_POINTERS
 115         bool
 116
 117 config GENERIC_HWEIGHT
 118         def_bool y
 119
 120 config GENERIC_GPIO
 121         bool
 122
 123 config ARCH_MAY_HAVE_PC_FDC
 124         def_bool y
 125
 126 config RWSEM_GENERIC_SPINLOCK
 127         def_bool !X86_XADD
 128
 129 config RWSEM_XCHGADD_ALGORITHM
 130         def_bool X86_XADD
 131
 132 config ARCH_HAS_CPU_IDLE_WAIT
 133         def_bool y
 134
 135 config GENERIC_CALIBRATE_DELAY
 136         def_bool y
 137
 138 config GENERIC_TIME_VSYSCALL
 139         bool
 140         default X86_64
 141
 142 config ARCH_HAS_CPU_RELAX
 143         def_bool y
 144
 145 config ARCH_HAS_DEFAULT_IDLE
 146         def_bool y
 147
 148 config ARCH_HAS_CACHE_LINE_SIZE
 149         def_bool y
 150
 151 config HAVE_SETUP_PER_CPU_AREA
 152         def_bool y
 153
 154 config HAVE_DYNAMIC_PER_CPU_AREA
 155         def_bool y
 156
 157 config HAVE_CPUMASK_OF_CPU_MAP
 158         def_bool X86_64_SMP
 159
 160 config ARCH_HIBERNATION_POSSIBLE
 161         def_bool y
 162
 163 config ARCH_SUSPEND_POSSIBLE
 164         def_bool y
 165
 166 config ZONE_DMA32
 167         bool
 168         default X86_64
 169
 170 config ARCH_POPULATES_NODE_MAP
 171         def_bool y
 172
 173 config AUDIT_ARCH
 174         bool
 175         default X86_64
 176
 177 config ARCH_SUPPORTS_OPTIMIZED_INLINING
 178         def_bool y
 179
 180 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
 181         def_bool y
 182
 183 # Use the generic interrupt handling code in kernel/irq/:
 184 config GENERIC_HARDIRQS
 185         bool
 186         default y
 187
 188 config GENERIC_HARDIRQS_NO__DO_IRQ
 189        def_bool y
 190
 191 config GENERIC_IRQ_PROBE
 192         bool
 193         default y
 194
 195 config GENERIC_PENDING_IRQ
 196         bool
 197         depends on GENERIC_HARDIRQS && SMP
 198         default y
 199
 200 config USE_GENERIC_SMP_HELPERS
 201         def_bool y
 202         depends on SMP
 203
 204 config X86_32_SMP
 205         def_bool y
 206         depends on X86_32 && SMP
 207
 208 config X86_64_SMP
 209         def_bool y
 210         depends on X86_64 && SMP
 211
 212 config X86_HT
 213         bool
 214         depends on SMP
 215         default y
 216
 217 config X86_TRAMPOLINE
 218         bool
 219         depends on SMP || (64BIT && ACPI_SLEEP)
 220         default y
 221
 222 config X86_32_LAZY_GS
 223         def_bool y
 224         depends on X86_32 && !CC_STACKPROTECTOR
 225
 226 config KTIME_SCALAR
 227         def_bool X86_32
 228 source "init/Kconfig"
 229 source "kernel/Kconfig.freezer"
 230
 231 menu "Processor type and features"
 232
 233 source "kernel/time/Kconfig"
 234
 235 config SMP
 236         bool "Symmetric multi-processing support"
 237         ---help---
 238           This enables support for systems with more than one CPU. If you have
 239           a system with only one CPU, like most personal computers, say N. If
 240           you have a system with more than one CPU, say Y.
 241
 242           If you say N here, the kernel will run on single and multiprocessor
 243           machines, but will use only one CPU of a multiprocessor machine. If
 244           you say Y here, the kernel will run on many, but not all,
 245           singleprocessor machines. On a singleprocessor machine, the kernel
 246           will run faster if you say N here.
 247
 248           Note that if you say Y here and choose architecture "586" or
 249           "Pentium" under "Processor family", the kernel will not work on 486
 250           architectures. Similarly, multiprocessor kernels for the "PPro"
 251           architecture may not work on all Pentium based boards.
 252
 253           People using multiprocessor machines who say Y here should also say
 254           Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
 255           Management" code will be disabled if you say Y here.
 256
 257           See also <file:Documentation/i386/IO-APIC.txt>,
 258           <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
 259           <http://www.tldp.org/docs.html#howto>.
 260
 261           If you don't know what to do here, say N.
 262
 263 config X86_X2APIC
 264         bool "Support x2apic"
 265         depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
 266         ---help---
 267           This enables x2apic support on CPUs that have this feature.
 268
 269           This allows 32-bit apic IDs (so it can support very large systems),
 270           and accesses the local apic via MSRs not via mmio.
 271
 272           If you don't know what to do here, say N.
 273
 274 config SPARSE_IRQ
 275         bool "Support sparse irq numbering"
 276         depends on PCI_MSI || HT_IRQ
 277         ---help---
 278           This enables support for sparse irqs. This is useful for distro
 279           kernels that want to define a high CONFIG_NR_CPUS value but still
 280           want to have low kernel memory footprint on smaller machines.
 281
 282           ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
 283             out the irq_desc[] array in a more NUMA-friendly way. )
 284
 285           If you don't know what to do here, say N.
 286
 287 config NUMA_IRQ_DESC
 288         def_bool y
 289         depends on SPARSE_IRQ && NUMA
 290
 291 config X86_MPPARSE
 292         bool "Enable MPS table" if ACPI
 293         default y
 294         depends on X86_LOCAL_APIC
 295         ---help---
 296           For old smp systems that do not have proper acpi support. Newer systems
 297           (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
 298
 299 config X86_BIGSMP
 300         bool "Support for big SMP systems with more than 8 CPUs"
 301         depends on X86_32 && SMP
 302         ---help---
 303           This option is needed for the systems that have more than 8 CPUs
 304
 305 if X86_32
 306 config X86_EXTENDED_PLATFORM
 307         bool "Support for extended (non-PC) x86 platforms"
 308         default y
 309         ---help---
 310           If you disable this option then the kernel will only support
 311           standard PC platforms. (which covers the vast majority of
 312           systems out there.)
 313
 314           If you enable this option then you'll be able to select support
 315           for the following (non-PC) 32 bit x86 platforms:
 316                 AMD Elan
 317                 NUMAQ (IBM/Sequent)
 318                 RDC R-321x SoC
 319                 SGI 320/540 (Visual Workstation)
 320                 Summit/EXA (IBM x440)
 321                 Unisys ES7000 IA32 series
 322
 323           If you have one of these systems, or if you want to build a
 324           generic distribution kernel, say Y here - otherwise say N.
 325 endif
 326
 327 if X86_64
 328 config X86_EXTENDED_PLATFORM
 329         bool "Support for extended (non-PC) x86 platforms"
 330         default y
 331         ---help---
 332           If you disable this option then the kernel will only support
 333           standard PC platforms. (which covers the vast majority of
 334           systems out there.)
 335
 336           If you enable this option then you'll be able to select support
 337           for the following (non-PC) 64 bit x86 platforms:
 338                 ScaleMP vSMP
 339                 SGI Ultraviolet
 340
 341           If you have one of these systems, or if you want to build a
 342           generic distribution kernel, say Y here - otherwise say N.
 343 endif
 344 # This is an alphabetically sorted list of 64 bit extended platforms
 345 # Please maintain the alphabetic order if and when there are additions
 346
 347 config X86_VSMP
 348         bool "ScaleMP vSMP"
 349         select PARAVIRT
 350         depends on X86_64 && PCI
 351         depends on X86_EXTENDED_PLATFORM
 352         ---help---
 353           Support for ScaleMP vSMP systems.  Say 'Y' here if this kernel is
 354           supposed to run on these EM64T-based machines.  Only choose this option
 355           if you have one of these machines.
 356
 357 config X86_UV
 358         bool "SGI Ultraviolet"
 359         depends on X86_64
 360         depends on X86_EXTENDED_PLATFORM
 361         depends on NUMA
 362         depends on X86_X2APIC
 363         ---help---
 364           This option is needed in order to support SGI Ultraviolet systems.
 365           If you don't have one of these, you should say N here.
 366
 367 # Following is an alphabetically sorted list of 32 bit extended platforms
 368 # Please maintain the alphabetic order if and when there are additions
 369
 370 config X86_ELAN
 371         bool "AMD Elan"
 372         depends on X86_32
 373         depends on X86_EXTENDED_PLATFORM
 374         ---help---
 375           Select this for an AMD Elan processor.
 376
 377           Do not use this option for K6/Athlon/Opteron processors!
 378
 379           If unsure, choose "PC-compatible" instead.
 380
 381 config X86_RDC321X
 382         bool "RDC R-321x SoC"
 383         depends on X86_32
 384         depends on X86_EXTENDED_PLATFORM
 385         select M486
 386         select X86_REBOOTFIXUPS
 387         ---help---
 388           This option is needed for RDC R-321x system-on-chip, also known
 389           as R-8610-(G).
 390           If you don't have one of these chips, you should say N here.
 391
 392 config X86_32_NON_STANDARD
 393         bool "Support non-standard 32-bit SMP architectures"
 394         depends on X86_32 && SMP
 395         depends on X86_EXTENDED_PLATFORM
 396         ---help---
 397           This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
 398           subarchitectures.  It is intended for a generic binary kernel.
 399           if you select them all, kernel will probe it one by one. and will
 400           fallback to default.
 401
 402 # Alphabetically sorted list of Non standard 32 bit platforms
 403
 404 config X86_NUMAQ
 405         bool "NUMAQ (IBM/Sequent)"
 406         depends on X86_32_NON_STANDARD
 407         select NUMA
 408         select X86_MPPARSE
 409         ---help---
 410           This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
 411           NUMA multiquad box. This changes the way that processors are
 412           bootstrapped, and uses Clustered Logical APIC addressing mode instead
 413           of Flat Logical.  You will need a new lynxer.elf file to flash your
 414           firmware with - send email to <Martin.Bligh@us.ibm.com>.
 415
 416 config X86_VISWS
 417         bool "SGI 320/540 (Visual Workstation)"
 418         depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
 419         depends on X86_32_NON_STANDARD
 420         ---help---
 421           The SGI Visual Workstation series is an IA32-based workstation
 422           based on SGI systems chips with some legacy PC hardware attached.
 423
 424           Say Y here to create a kernel to run on the SGI 320 or 540.
 425
 426           A kernel compiled for the Visual Workstation will run on general
 427           PCs as well. See <file:Documentation/sgi-visws.txt> for details.
 428
 429 config X86_SUMMIT
 430         bool "Summit/EXA (IBM x440)"
 431         depends on X86_32_NON_STANDARD
 432         ---help---
 433           This option is needed for IBM systems that use the Summit/EXA chipset.
 434           In particular, it is needed for the x440.
 435
 436 config X86_ES7000
 437         bool "Unisys ES7000 IA32 series"
 438         depends on X86_32_NON_STANDARD && X86_BIGSMP
 439         ---help---
 440           Support for Unisys ES7000 systems.  Say 'Y' here if this kernel is
 441           supposed to run on an IA32-based Unisys ES7000 system.
 442
 443 config SCHED_OMIT_FRAME_POINTER
 444         def_bool y
 445         prompt "Single-depth WCHAN output"
 446         depends on X86
 447         ---help---
 448           Calculate simpler /proc/<PID>/wchan values. If this option
 449           is disabled then wchan values will recurse back to the
 450           caller function. This provides more accurate wchan values,
 451           at the expense of slightly more scheduling overhead.
 452
 453           If in doubt, say "Y".
 454
 455 menuconfig PARAVIRT_GUEST
 456         bool "Paravirtualized guest support"
 457         ---help---
 458           Say Y here to get to see options related to running Linux under
 459           various hypervisors.  This option alone does not add any kernel code.
 460
 461           If you say N, all options in this submenu will be skipped and disabled.
 462
 463 if PARAVIRT_GUEST
 464
 465 source "arch/x86/xen/Kconfig"
 466
 467 config VMI
 468         bool "VMI Guest support"
 469         select PARAVIRT
 470         depends on X86_32
 471         ---help---
 472           VMI provides a paravirtualized interface to the VMware ESX server
 473           (it could be used by other hypervisors in theory too, but is not
 474           at the moment), by linking the kernel to a GPL-ed ROM module
 475           provided by the hypervisor.
 476
 477 config KVM_CLOCK
 478         bool "KVM paravirtualized clock"
 479         select PARAVIRT
 480         select PARAVIRT_CLOCK
 481         ---help---
 482           Turning on this option will allow you to run a paravirtualized clock
 483           when running over the KVM hypervisor. Instead of relying on a PIT
 484           (or probably other) emulation by the underlying device model, the host
 485           provides the guest with timing infrastructure such as time of day, and
 486           system time
 487
 488 config KVM_GUEST
 489         bool "KVM Guest support"
 490         select PARAVIRT
 491         ---help---
 492           This option enables various optimizations for running under the KVM
 493           hypervisor.
 494
 495 source "arch/x86/lguest/Kconfig"
 496
 497 config PARAVIRT
 498         bool "Enable paravirtualization code"
 499         ---help---
 500           This changes the kernel so it can modify itself when it is run
 501           under a hypervisor, potentially improving performance significantly
 502           over full virtualization.  However, when run without a hypervisor
 503           the kernel is theoretically slower and slightly larger.
 504
 505 config PARAVIRT_SPINLOCKS
 506         bool "Paravirtualization layer for spinlocks"
 507         depends on PARAVIRT && SMP && EXPERIMENTAL
 508         ---help---
 509           Paravirtualized spinlocks allow a pvops backend to replace the
 510           spinlock implementation with something virtualization-friendly
 511           (for example, block the virtual CPU rather than spinning).
 512
 513           Unfortunately the downside is an up to 5% performance hit on
 514           native kernels, with various workloads.
 515
 516           If you are unsure how to answer this question, answer N.
 517
 518 config PARAVIRT_CLOCK
 519         bool
 520         default n
 521
 522 endif
 523
 524 config PARAVIRT_DEBUG
 525         bool "paravirt-ops debugging"
 526         depends on PARAVIRT && DEBUG_KERNEL
 527         ---help---
 528           Enable to debug paravirt_ops internals.  Specifically, BUG if
 529           a paravirt_op is missing when it is called.
 530
 531 config MEMTEST
 532         bool "Memtest"
 533         ---help---
 534           This option adds a kernel parameter 'memtest', which allows memtest
 535           to be set.
 536                 memtest=0, mean disabled; -- default
 537                 memtest=1, mean do 1 test pattern;
 538                 ...
 539                 memtest=4, mean do 4 test patterns.
 540           If you are unsure how to answer this question, answer N.
 541
 542 config X86_SUMMIT_NUMA
 543         def_bool y
 544         depends on X86_32 && NUMA && X86_32_NON_STANDARD
 545
 546 config X86_CYCLONE_TIMER
 547         def_bool y
 548         depends on X86_32_NON_STANDARD
 549
 550 source "arch/x86/Kconfig.cpu"
 551
 552 config HPET_TIMER
 553         def_bool X86_64
 554         prompt "HPET Timer Support" if X86_32
 555         ---help---
 556           Use the IA-PC HPET (High Precision Event Timer) to manage
 557           time in preference to the PIT and RTC, if a HPET is
 558           present.
 559           HPET is the next generation timer replacing legacy 8254s.
 560           The HPET provides a stable time base on SMP
 561           systems, unlike the TSC, but it is more expensive to access,
 562           as it is off-chip.  You can find the HPET spec at
 563           <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
 564
 565           You can safely choose Y here.  However, HPET will only be
 566           activated if the platform and the BIOS support this feature.
 567           Otherwise the 8254 will be used for timing services.
 568
 569           Choose N to continue using the legacy 8254 timer.
 570
 571 config HPET_EMULATE_RTC
 572         def_bool y
 573         depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
 574
 575 # Mark as embedded because too many people got it wrong.
 576 # The code disables itself when not needed.
 577 config DMI
 578         default y
 579         bool "Enable DMI scanning" if EMBEDDED
 580         ---help---
 581           Enabled scanning of DMI to identify machine quirks. Say Y
 582           here unless you have verified that your setup is not
 583           affected by entries in the DMI blacklist. Required by PNP
 584           BIOS code.
 585
 586 config GART_IOMMU
 587         bool "GART IOMMU support" if EMBEDDED
 588         default y
 589         select SWIOTLB
 590         select AGP
 591         depends on X86_64 && PCI
 592         ---help---
 593           Support for full DMA access of devices with 32bit memory access only
 594           on systems with more than 3GB. This is usually needed for USB,
 595           sound, many IDE/SATA chipsets and some other devices.
 596           Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
 597           based hardware IOMMU and a software bounce buffer based IOMMU used
 598           on Intel systems and as fallback.
 599           The code is only active when needed (enough memory and limited
 600           device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
 601           too.
 602
 603 config CALGARY_IOMMU
 604         bool "IBM Calgary IOMMU support"
 605         select SWIOTLB
 606         depends on X86_64 && PCI && EXPERIMENTAL
 607         ---help---
 608           Support for hardware IOMMUs in IBM's xSeries x366 and x460
 609           systems. Needed to run systems with more than 3GB of memory
 610           properly with 32-bit PCI devices that do not support DAC
 611           (Double Address Cycle). Calgary also supports bus level
 612           isolation, where all DMAs pass through the IOMMU.  This
 613           prevents them from going anywhere except their intended
 614           destination. This catches hard-to-find kernel bugs and
 615           mis-behaving drivers and devices that do not use the DMA-API
 616           properly to set up their DMA buffers.  The IOMMU can be
 617           turned off at boot time with the iommu=off parameter.
 618           Normally the kernel will make the right choice by itself.
 619           If unsure, say Y.
 620
 621 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
 622         def_bool y
 623         prompt "Should Calgary be enabled by default?"
 624         depends on CALGARY_IOMMU
 625         ---help---
 626           Should Calgary be enabled by default? if you choose 'y', Calgary
 627           will be used (if it exists). If you choose 'n', Calgary will not be
 628           used even if it exists. If you choose 'n' and would like to use
 629           Calgary anyway, pass 'iommu=calgary' on the kernel command line.
 630           If unsure, say Y.
 631
 632 config AMD_IOMMU
 633         bool "AMD IOMMU support"
 634         select SWIOTLB
 635         select PCI_MSI
 636         depends on X86_64 && PCI && ACPI
 637         ---help---
 638           With this option you can enable support for AMD IOMMU hardware in
 639           your system. An IOMMU is a hardware component which provides
 640           remapping of DMA memory accesses from devices. With an AMD IOMMU you
 641           can isolate the the DMA memory of different devices and protect the
 642           system from misbehaving device drivers or hardware.
 643
 644           You can find out if your system has an AMD IOMMU if you look into
 645           your BIOS for an option to enable it or if you have an IVRS ACPI
 646           table.
 647
 648 config AMD_IOMMU_STATS
 649         bool "Export AMD IOMMU statistics to debugfs"
 650         depends on AMD_IOMMU
 651         select DEBUG_FS
 652         ---help---
 653           This option enables code in the AMD IOMMU driver to collect various
 654           statistics about whats happening in the driver and exports that
 655           information to userspace via debugfs.
 656           If unsure, say N.
 657
 658 # need this always selected by IOMMU for the VIA workaround
 659 config SWIOTLB
 660         def_bool y if X86_64
 661         ---help---
 662           Support for software bounce buffers used on x86-64 systems
 663           which don't have a hardware IOMMU (e.g. the current generation
 664           of Intel's x86-64 CPUs). Using this PCI devices which can only
 665           access 32-bits of memory can be used on systems with more than
 666           3 GB of memory. If unsure, say Y.
 667
 668 config IOMMU_HELPER
 669         def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
 670
 671 config IOMMU_API
 672         def_bool (AMD_IOMMU || DMAR)
 673
 674 config MAXSMP
 675         bool "Configure Maximum number of SMP Processors and NUMA Nodes"
 676         depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
 677         select CPUMASK_OFFSTACK
 678         default n
 679         ---help---
 680           Configure maximum number of CPUS and NUMA Nodes for this architecture.
 681           If unsure, say N.
 682
 683 config NR_CPUS
 684         int "Maximum number of CPUs" if SMP && !MAXSMP
 685         range 2 8 if SMP && X86_32 && !X86_BIGSMP
 686         range 2 512 if SMP && !MAXSMP
 687         default "1" if !SMP
 688         default "4096" if MAXSMP
 689         default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
 690         default "8" if SMP
 691         ---help---
 692           This allows you to specify the maximum number of CPUs which this
 693           kernel will support.  The maximum supported value is 512 and the
 694           minimum value which makes sense is 2.
 695
 696           This is purely to save memory - each supported CPU adds
 697           approximately eight kilobytes to the kernel image.
 698
 699 config SCHED_SMT
 700         bool "SMT (Hyperthreading) scheduler support"
 701         depends on X86_HT
 702         ---help---
 703           SMT scheduler support improves the CPU scheduler's decision making
 704           when dealing with Intel Pentium 4 chips with HyperThreading at a
 705           cost of slightly increased overhead in some places. If unsure say
 706           N here.
 707
 708 config SCHED_MC
 709         def_bool y
 710         prompt "Multi-core scheduler support"
 711         depends on X86_HT
 712         ---help---
 713           Multi-core scheduler support improves the CPU scheduler's decision
 714           making when dealing with multi-core CPU chips at a cost of slightly
 715           increased overhead in some places. If unsure say N here.
 716
 717 source "kernel/Kconfig.preempt"
 718
 719 config X86_UP_APIC
 720         bool "Local APIC support on uniprocessors"
 721         depends on X86_32 && !SMP && !X86_32_NON_STANDARD
 722         ---help---
 723           A local APIC (Advanced Programmable Interrupt Controller) is an
 724           integrated interrupt controller in the CPU. If you have a single-CPU
 725           system which has a processor with a local APIC, you can say Y here to
 726           enable and use it. If you say Y here even though your machine doesn't
 727           have a local APIC, then the kernel will still run with no slowdown at
 728           all. The local APIC supports CPU-generated self-interrupts (timer,
 729           performance counters), and the NMI watchdog which detects hard
 730           lockups.
 731
 732 config X86_UP_IOAPIC
 733         bool "IO-APIC support on uniprocessors"
 734         depends on X86_UP_APIC
 735         ---help---
 736           An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
 737           SMP-capable replacement for PC-style interrupt controllers. Most
 738           SMP systems and many recent uniprocessor systems have one.
 739
 740           If you have a single-CPU system with an IO-APIC, you can say Y here
 741           to use it. If you say Y here even though your machine doesn't have
 742           an IO-APIC, then the kernel will still run with no slowdown at all.
 743
 744 config X86_LOCAL_APIC
 745         def_bool y
 746         depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
 747
 748 config X86_IO_APIC
 749         def_bool y
 750         depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
 751
 752 config X86_VISWS_APIC
 753         def_bool y
 754         depends on X86_32 && X86_VISWS
 755
 756 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
 757         bool "Reroute for broken boot IRQs"
 758         default n
 759         depends on X86_IO_APIC
 760         ---help---
 761           This option enables a workaround that fixes a source of
 762           spurious interrupts. This is recommended when threaded
 763           interrupt handling is used on systems where the generation of
 764           superfluous "boot interrupts" cannot be disabled.
 765
 766           Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
 767           entry in the chipset's IO-APIC is masked (as, e.g. the RT
 768           kernel does during interrupt handling). On chipsets where this
 769           boot IRQ generation cannot be disabled, this workaround keeps
 770           the original IRQ line masked so that only the equivalent "boot
 771           IRQ" is delivered to the CPUs. The workaround also tells the
 772           kernel to set up the IRQ handler on the boot IRQ line. In this
 773           way only one interrupt is delivered to the kernel. Otherwise
 774           the spurious second interrupt may cause the kernel to bring
 775           down (vital) interrupt lines.
 776
 777           Only affects "broken" chipsets. Interrupt sharing may be
 778           increased on these systems.
 779
 780 config X86_MCE
 781         bool "Machine Check Exception"
 782         ---help---
 783           Machine Check Exception support allows the processor to notify the
 784           kernel if it detects a problem (e.g. overheating, component failure).
 785           The action the kernel takes depends on the severity of the problem,
 786           ranging from a warning message on the console, to halting the machine.
 787           Your processor must be a Pentium or newer to support this - check the
 788           flags in /proc/cpuinfo for mce.  Note that some older Pentium systems
 789           have a design flaw which leads to false MCE events - hence MCE is
 790           disabled on all P5 processors, unless explicitly enabled with "mce"
 791           as a boot argument.  Similarly, if MCE is built in and creates a
 792           problem on some new non-standard machine, you can boot with "nomce"
 793           to disable it.  MCE support simply ignores non-MCE processors like
 794           the 386 and 486, so nearly everyone can say Y here.
 795
 796 config X86_OLD_MCE
 797         depends on X86_32 && X86_MCE
 798         bool "Use legacy machine check code (will go away)"
 799         default n
 800         select X86_ANCIENT_MCE
 801         ---help---
 802           Use the old i386 machine check code. This is merely intended for
 803           testing in a transition period. Try this if you run into any machine
 804           check related software problems, but report the problem to
 805           linux-kernel.  When in doubt say no.
 806
 807 config X86_NEW_MCE
 808         depends on X86_MCE
 809         bool
 810         default y if (!X86_OLD_MCE && X86_32) || X86_64
 811
 812 config X86_MCE_INTEL
 813         def_bool y
 814         prompt "Intel MCE features"
 815         depends on X86_NEW_MCE && X86_LOCAL_APIC
 816         ---help---
 817            Additional support for intel specific MCE features such as
 818            the thermal monitor.
 819
 820 config X86_MCE_AMD
 821         def_bool y
 822         prompt "AMD MCE features"
 823         depends on X86_NEW_MCE && X86_LOCAL_APIC
 824         ---help---
 825            Additional support for AMD specific MCE features such as
 826            the DRAM Error Threshold.
 827
 828 config X86_ANCIENT_MCE
 829         def_bool n
 830         depends on X86_32
 831         prompt "Support for old Pentium 5 / WinChip machine checks"
 832         ---help---
 833           Include support for machine check handling on old Pentium 5 or WinChip
 834           systems. These typically need to be enabled explicitely on the command
 835           line.
 836
 837 config X86_MCE_THRESHOLD
 838         depends on X86_MCE_AMD || X86_MCE_INTEL
 839         bool
 840         default y
 841
 842 config X86_MCE_INJECT
 843         depends on X86_NEW_MCE
 844         tristate "Machine check injector support"
 845         ---help---
 846           Provide support for injecting machine checks for testing purposes.
 847           If you don't know what a machine check is and you don't do kernel
 848           QA it is safe to say n.
 849
 850 config X86_MCE_NONFATAL
 851         tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
 852         depends on X86_OLD_MCE
 853         ---help---
 854           Enabling this feature starts a timer that triggers every 5 seconds which
 855           will look at the machine check registers to see if anything happened.
 856           Non-fatal problems automatically get corrected (but still logged).
 857           Disable this if you don't want to see these messages.
 858           Seeing the messages this option prints out may be indicative of dying
 859           or out-of-spec (ie, overclocked) hardware.
 860           This option only does something on certain CPUs.
 861           (AMD Athlon/Duron and Intel Pentium 4)
 862
 863 config X86_MCE_P4THERMAL
 864         bool "check for P4 thermal throttling interrupt."
 865         depends on X86_OLD_MCE && X86_MCE && (X86_UP_APIC || SMP)
 866         ---help---
 867           Enabling this feature will cause a message to be printed when the P4
 868           enters thermal throttling.
 869
 870 config X86_THERMAL_VECTOR
 871         def_bool y
 872         depends on X86_MCE_P4THERMAL || X86_MCE_INTEL
 873
 874 config VM86
 875         bool "Enable VM86 support" if EMBEDDED
 876         default y
 877         depends on X86_32
 878         ---help---
 879           This option is required by programs like DOSEMU to run 16-bit legacy
 880           code on X86 processors. It also may be needed by software like
 881           XFree86 to initialize some video cards via BIOS. Disabling this
 882           option saves about 6k.
 883
 884 config TOSHIBA
 885         tristate "Toshiba Laptop support"
 886         depends on X86_32
 887         ---help---
 888           This adds a driver to safely access the System Management Mode of
 889           the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
 890           not work on models with a Phoenix BIOS. The System Management Mode
 891           is used to set the BIOS and power saving options on Toshiba portables.
 892
 893           For information on utilities to make use of this driver see the
 894           Toshiba Linux utilities web site at:
 895           <http://www.buzzard.org.uk/toshiba/>.
 896
 897           Say Y if you intend to run this kernel on a Toshiba portable.
 898           Say N otherwise.
 899
 900 config I8K
 901         tristate "Dell laptop support"
 902         ---help---
 903           This adds a driver to safely access the System Management Mode
 904           of the CPU on the Dell Inspiron 8000. The System Management Mode
 905           is used to read cpu temperature and cooling fan status and to
 906           control the fans on the I8K portables.
 907
 908           This driver has been tested only on the Inspiron 8000 but it may
 909           also work with other Dell laptops. You can force loading on other
 910           models by passing the parameter `force=1' to the module. Use at
 911           your own risk.
 912
 913           For information on utilities to make use of this driver see the
 914           I8K Linux utilities web site at:
 915           <http://people.debian.org/~dz/i8k/>
 916
 917           Say Y if you intend to run this kernel on a Dell Inspiron 8000.
 918           Say N otherwise.
 919
 920 config X86_REBOOTFIXUPS
 921         bool "Enable X86 board specific fixups for reboot"
 922         depends on X86_32
 923         ---help---
 924           This enables chipset and/or board specific fixups to be done
 925           in order to get reboot to work correctly. This is only needed on
 926           some combinations of hardware and BIOS. The symptom, for which
 927           this config is intended, is when reboot ends with a stalled/hung
 928           system.
 929
 930           Currently, the only fixup is for the Geode machines using
 931           CS5530A and CS5536 chipsets and the RDC R-321x SoC.
 932
 933           Say Y if you want to enable the fixup. Currently, it's safe to
 934           enable this option even if you don't need it.
 935           Say N otherwise.
 936
 937 config MICROCODE
 938         tristate "/dev/cpu/microcode - microcode support"
 939         select FW_LOADER
 940         ---help---
 941           If you say Y here, you will be able to update the microcode on
 942           certain Intel and AMD processors. The Intel support is for the
 943           IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
 944           Pentium 4, Xeon etc. The AMD support is for family 0x10 and
 945           0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
 946           You will obviously need the actual microcode binary data itself
 947           which is not shipped with the Linux kernel.
 948
 949           This option selects the general module only, you need to select
 950           at least one vendor specific module as well.
 951
 952           To compile this driver as a module, choose M here: the
 953           module will be called microcode.
 954
 955 config MICROCODE_INTEL
 956         bool "Intel microcode patch loading support"
 957         depends on MICROCODE
 958         default MICROCODE
 959         select FW_LOADER
 960         ---help---
 961           This options enables microcode patch loading support for Intel
 962           processors.
 963
 964           For latest news and information on obtaining all the required
 965           Intel ingredients for this driver, check:
 966           <http://www.urbanmyth.org/microcode/>.
 967
 968 config MICROCODE_AMD
 969         bool "AMD microcode patch loading support"
 970         depends on MICROCODE
 971         select FW_LOADER
 972         ---help---
 973           If you select this option, microcode patch loading support for AMD
 974           processors will be enabled.
 975
 976 config MICROCODE_OLD_INTERFACE
 977         def_bool y
 978         depends on MICROCODE
 979
 980 config X86_MSR
 981         tristate "/dev/cpu/*/msr - Model-specific register support"
 982         ---help---
 983           This device gives privileged processes access to the x86
 984           Model-Specific Registers (MSRs).  It is a character device with
 985           major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
 986           MSR accesses are directed to a specific CPU on multi-processor
 987           systems.
 988
 989 config X86_CPUID
 990         tristate "/dev/cpu/*/cpuid - CPU information support"
 991         ---help---
 992           This device gives processes access to the x86 CPUID instruction to
 993           be executed on a specific processor.  It is a character device
 994           with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
 995           /dev/cpu/31/cpuid.
 996
 997 config X86_CPU_DEBUG
 998         tristate "/sys/kernel/debug/x86/cpu/* - CPU Debug support"
 999         ---help---
1000           If you select this option, this will provide various x86 CPUs
1001           information through debugfs.
1002
1003 choice
1004         prompt "High Memory Support"
1005         default HIGHMEM4G if !X86_NUMAQ
1006         default HIGHMEM64G if X86_NUMAQ
1007         depends on X86_32
1008
1009 config NOHIGHMEM
1010         bool "off"
1011         depends on !X86_NUMAQ
1012         ---help---
1013           Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1014           However, the address space of 32-bit x86 processors is only 4
1015           Gigabytes large. That means that, if you have a large amount of
1016           physical memory, not all of it can be "permanently mapped" by the
1017           kernel. The physical memory that's not permanently mapped is called
1018           "high memory".
1019
1020           If you are compiling a kernel which will never run on a machine with
1021           more than 1 Gigabyte total physical RAM, answer "off" here (default
1022           choice and suitable for most users). This will result in a "3GB/1GB"
1023           split: 3GB are mapped so that each process sees a 3GB virtual memory
1024           space and the remaining part of the 4GB virtual memory space is used
1025           by the kernel to permanently map as much physical memory as
1026           possible.
1027
1028           If the machine has between 1 and 4 Gigabytes physical RAM, then
1029           answer "4GB" here.
1030
1031           If more than 4 Gigabytes is used then answer "64GB" here. This
1032           selection turns Intel PAE (Physical Address Extension) mode on.
1033           PAE implements 3-level paging on IA32 processors. PAE is fully
1034           supported by Linux, PAE mode is implemented on all recent Intel
1035           processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1036           then the kernel will not boot on CPUs that don't support PAE!
1037
1038           The actual amount of total physical memory will either be
1039           auto detected or can be forced by using a kernel command line option
1040           such as "mem=256M". (Try "man bootparam" or see the documentation of
1041           your boot loader (lilo or loadlin) about how to pass options to the
1042           kernel at boot time.)
1043
1044           If unsure, say "off".
1045
1046 config HIGHMEM4G
1047         bool "4GB"
1048         depends on !X86_NUMAQ
1049         ---help---
1050           Select this if you have a 32-bit processor and between 1 and 4
1051           gigabytes of physical RAM.
1052
1053 config HIGHMEM64G
1054         bool "64GB"
1055         depends on !M386 && !M486
1056         select X86_PAE
1057         ---help---
1058           Select this if you have a 32-bit processor and more than 4
1059           gigabytes of physical RAM.
1060
1061 endchoice
1062
1063 choice
1064         depends on EXPERIMENTAL
1065         prompt "Memory split" if EMBEDDED
1066         default VMSPLIT_3G
1067         depends on X86_32
1068         ---help---
1069           Select the desired split between kernel and user memory.
1070
1071           If the address range available to the kernel is less than the
1072           physical memory installed, the remaining memory will be available
1073           as "high memory". Accessing high memory is a little more costly
1074           than low memory, as it needs to be mapped into the kernel first.
1075           Note that increasing the kernel address space limits the range
1076           available to user programs, making the address space there
1077           tighter.  Selecting anything other than the default 3G/1G split
1078           will also likely make your kernel incompatible with binary-only
1079           kernel modules.
1080
1081           If you are not absolutely sure what you are doing, leave this
1082           option alone!
1083
1084         config VMSPLIT_3G
1085                 bool "3G/1G user/kernel split"
1086         config VMSPLIT_3G_OPT
1087                 depends on !X86_PAE
1088                 bool "3G/1G user/kernel split (for full 1G low memory)"
1089         config VMSPLIT_2G
1090                 bool "2G/2G user/kernel split"
1091         config VMSPLIT_2G_OPT
1092                 depends on !X86_PAE
1093                 bool "2G/2G user/kernel split (for full 2G low memory)"
1094         config VMSPLIT_1G
1095                 bool "1G/3G user/kernel split"
1096 endchoice
1097
1098 config PAGE_OFFSET
1099         hex
1100         default 0xB0000000 if VMSPLIT_3G_OPT
1101         default 0x80000000 if VMSPLIT_2G
1102         default 0x78000000 if VMSPLIT_2G_OPT
1103         default 0x40000000 if VMSPLIT_1G
1104         default 0xC0000000
1105         depends on X86_32
1106
1107 config HIGHMEM
1108         def_bool y
1109         depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1110
1111 config X86_PAE
1112         bool "PAE (Physical Address Extension) Support"
1113         depends on X86_32 && !HIGHMEM4G
1114         ---help---
1115           PAE is required for NX support, and furthermore enables
1116           larger swapspace support for non-overcommit purposes. It
1117           has the cost of more pagetable lookup overhead, and also
1118           consumes more pagetable space per process.
1119
1120 config ARCH_PHYS_ADDR_T_64BIT
1121         def_bool X86_64 || X86_PAE
1122
1123 config DIRECT_GBPAGES
1124         bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
1125         default y
1126         depends on X86_64
1127         ---help---
1128           Allow the kernel linear mapping to use 1GB pages on CPUs that
1129           support it. This can improve the kernel's performance a tiny bit by
1130           reducing TLB pressure. If in doubt, say "Y".
1131
1132 # Common NUMA Features
1133 config NUMA
1134         bool "Numa Memory Allocation and Scheduler Support"
1135         depends on SMP
1136         depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
1137         default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
1138         ---help---
1139           Enable NUMA (Non Uniform Memory Access) support.
1140
1141           The kernel will try to allocate memory used by a CPU on the
1142           local memory controller of the CPU and add some more
1143           NUMA awareness to the kernel.
1144
1145           For 64-bit this is recommended if the system is Intel Core i7
1146           (or later), AMD Opteron, or EM64T NUMA.
1147
1148           For 32-bit this is only needed on (rare) 32-bit-only platforms
1149           that support NUMA topologies, such as NUMAQ / Summit, or if you
1150           boot a 32-bit kernel on a 64-bit NUMA platform.
1151
1152           Otherwise, you should say N.
1153
1154 comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1155         depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1156
1157 config K8_NUMA
1158         def_bool y
1159         prompt "Old style AMD Opteron NUMA detection"
1160         depends on X86_64 && NUMA && PCI
1161         ---help---
1162           Enable K8 NUMA node topology detection.  You should say Y here if
1163           you have a multi processor AMD K8 system. This uses an old
1164           method to read the NUMA configuration directly from the builtin
1165           Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
1166           instead, which also takes priority if both are compiled in.
1167
1168 config X86_64_ACPI_NUMA
1169         def_bool y
1170         prompt "ACPI NUMA detection"
1171         depends on X86_64 && NUMA && ACPI && PCI
1172         select ACPI_NUMA
1173         ---help---
1174           Enable ACPI SRAT based node topology detection.
1175
1176 # Some NUMA nodes have memory ranges that span
1177 # other nodes.  Even though a pfn is valid and
1178 # between a node's start and end pfns, it may not
1179 # reside on that node.  See memmap_init_zone()
1180 # for details.
1181 config NODES_SPAN_OTHER_NODES
1182         def_bool y
1183         depends on X86_64_ACPI_NUMA
1184
1185 config NUMA_EMU
1186         bool "NUMA emulation"
1187         depends on X86_64 && NUMA
1188         ---help---
1189           Enable NUMA emulation. A flat machine will be split
1190           into virtual nodes when booted with "numa=fake=N", where N is the
1191           number of nodes. This is only useful for debugging.
1192
1193 config NODES_SHIFT
1194         int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1195         range 1 9
1196         default "9" if MAXSMP
1197         default "6" if X86_64
1198         default "4" if X86_NUMAQ
1199         default "3"
1200         depends on NEED_MULTIPLE_NODES
1201         ---help---
1202           Specify the maximum number of NUMA Nodes available on the target
1203           system.  Increases memory reserved to accommodate various tables.
1204
1205 config HAVE_ARCH_BOOTMEM
1206         def_bool y
1207         depends on X86_32 && NUMA
1208
1209 config ARCH_HAVE_MEMORY_PRESENT
1210         def_bool y
1211         depends on X86_32 && DISCONTIGMEM
1212
1213 config NEED_NODE_MEMMAP_SIZE
1214         def_bool y
1215         depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1216
1217 config HAVE_ARCH_ALLOC_REMAP
1218         def_bool y
1219         depends on X86_32 && NUMA
1220
1221 config ARCH_FLATMEM_ENABLE
1222         def_bool y
1223         depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
1224
1225 config ARCH_DISCONTIGMEM_ENABLE
1226         def_bool y
1227         depends on NUMA && X86_32
1228
1229 config ARCH_DISCONTIGMEM_DEFAULT
1230         def_bool y
1231         depends on NUMA && X86_32
1232
1233 config ARCH_SPARSEMEM_DEFAULT
1234         def_bool y
1235         depends on X86_64
1236
1237 config ARCH_SPARSEMEM_ENABLE
1238         def_bool y
1239         depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
1240         select SPARSEMEM_STATIC if X86_32
1241         select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1242
1243 config ARCH_SELECT_MEMORY_MODEL
1244         def_bool y
1245         depends on ARCH_SPARSEMEM_ENABLE
1246
1247 config ARCH_MEMORY_PROBE
1248         def_bool X86_64
1249         depends on MEMORY_HOTPLUG
1250
1251 source "mm/Kconfig"
1252
1253 config HIGHPTE
1254         bool "Allocate 3rd-level pagetables from highmem"
1255         depends on X86_32 && (HIGHMEM4G || HIGHMEM64G)
1256         ---help---
1257           The VM uses one page table entry for each page of physical memory.
1258           For systems with a lot of RAM, this can be wasteful of precious
1259           low memory.  Setting this option will put user-space page table
1260           entries in high memory.
1261
1262 config X86_CHECK_BIOS_CORRUPTION
1263         bool "Check for low memory corruption"
1264         ---help---
1265           Periodically check for memory corruption in low memory, which
1266           is suspected to be caused by BIOS.  Even when enabled in the
1267           configuration, it is disabled at runtime.  Enable it by
1268           setting "memory_corruption_check=1" on the kernel command
1269           line.  By default it scans the low 64k of memory every 60
1270           seconds; see the memory_corruption_check_size and
1271           memory_corruption_check_period parameters in
1272           Documentation/kernel-parameters.txt to adjust this.
1273
1274           When enabled with the default parameters, this option has
1275           almost no overhead, as it reserves a relatively small amount
1276           of memory and scans it infrequently.  It both detects corruption
1277           and prevents it from affecting the running system.
1278
1279           It is, however, intended as a diagnostic tool; if repeatable
1280           BIOS-originated corruption always affects the same memory,
1281           you can use memmap= to prevent the kernel from using that
1282           memory.
1283
1284 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1285         bool "Set the default setting of memory_corruption_check"
1286         depends on X86_CHECK_BIOS_CORRUPTION
1287         default y
1288         ---help---
1289           Set whether the default state of memory_corruption_check is
1290           on or off.
1291
1292 config X86_RESERVE_LOW_64K
1293         bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
1294         default y
1295         ---help---
1296           Reserve the first 64K of physical RAM on BIOSes that are known
1297           to potentially corrupt that memory range. A numbers of BIOSes are
1298           known to utilize this area during suspend/resume, so it must not
1299           be used by the kernel.
1300
1301           Set this to N if you are absolutely sure that you trust the BIOS
1302           to get all its memory reservations and usages right.
1303
1304           If you have doubts about the BIOS (e.g. suspend/resume does not
1305           work or there's kernel crashes after certain hardware hotplug
1306           events) and it's not AMI or Phoenix, then you might want to enable
1307           X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
1308           corruption patterns.
1309
1310           Say Y if unsure.
1311
1312 config MATH_EMULATION
1313         bool
1314         prompt "Math emulation" if X86_32
1315         ---help---
1316           Linux can emulate a math coprocessor (used for floating point
1317           operations) if you don't have one. 486DX and Pentium processors have
1318           a math coprocessor built in, 486SX and 386 do not, unless you added
1319           a 487DX or 387, respectively. (The messages during boot time can
1320           give you some hints here ["man dmesg"].) Everyone needs either a
1321           coprocessor or this emulation.
1322
1323           If you don't have a math coprocessor, you need to say Y here; if you
1324           say Y here even though you have a coprocessor, the coprocessor will
1325           be used nevertheless. (This behavior can be changed with the kernel
1326           command line option "no387", which comes handy if your coprocessor
1327           is broken. Try "man bootparam" or see the documentation of your boot
1328           loader (lilo or loadlin) about how to pass options to the kernel at
1329           boot time.) This means that it is a good idea to say Y here if you
1330           intend to use this kernel on different machines.
1331
1332           More information about the internals of the Linux math coprocessor
1333           emulation can be found in <file:arch/x86/math-emu/README>.
1334
1335           If you are not sure, say Y; apart from resulting in a 66 KB bigger
1336           kernel, it won't hurt.
1337
1338 config MTRR
1339         bool "MTRR (Memory Type Range Register) support"
1340         ---help---
1341           On Intel P6 family processors (Pentium Pro, Pentium II and later)
1342           the Memory Type Range Registers (MTRRs) may be used to control
1343           processor access to memory ranges. This is most useful if you have
1344           a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1345           allows bus write transfers to be combined into a larger transfer
1346           before bursting over the PCI/AGP bus. This can increase performance
1347           of image write operations 2.5 times or more. Saying Y here creates a
1348           /proc/mtrr file which may be used to manipulate your processor's
1349           MTRRs. Typically the X server should use this.
1350
1351           This code has a reasonably generic interface so that similar
1352           control registers on other processors can be easily supported
1353           as well:
1354
1355           The Cyrix 6x86, 6x86MX and M II processors have Address Range
1356           Registers (ARRs) which provide a similar functionality to MTRRs. For
1357           these, the ARRs are used to emulate the MTRRs.
1358           The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1359           MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1360           write-combining. All of these processors are supported by this code
1361           and it makes sense to say Y here if you have one of them.
1362
1363           Saying Y here also fixes a problem with buggy SMP BIOSes which only
1364           set the MTRRs for the boot CPU and not for the secondary CPUs. This
1365           can lead to all sorts of problems, so it's good to say Y here.
1366
1367           You can safely say Y even if your machine doesn't have MTRRs, you'll
1368           just add about 9 KB to your kernel.
1369
1370           See <file:Documentation/x86/mtrr.txt> for more information.
1371
1372 config MTRR_SANITIZER
1373         def_bool y
1374         prompt "MTRR cleanup support"
1375         depends on MTRR
1376         ---help---
1377           Convert MTRR layout from continuous to discrete, so X drivers can
1378           add writeback entries.
1379
1380           Can be disabled with disable_mtrr_cleanup on the kernel command line.
1381           The largest mtrr entry size for a continuous block can be set with
1382           mtrr_chunk_size.
1383
1384           If unsure, say Y.
1385
1386 config MTRR_SANITIZER_ENABLE_DEFAULT
1387         int "MTRR cleanup enable value (0-1)"
1388         range 0 1
1389         default "0"
1390         depends on MTRR_SANITIZER
1391         ---help---
1392           Enable mtrr cleanup default value
1393
1394 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1395         int "MTRR cleanup spare reg num (0-7)"
1396         range 0 7
1397         default "1"
1398         depends on MTRR_SANITIZER
1399         ---help---
1400           mtrr cleanup spare entries default, it can be changed via
1401           mtrr_spare_reg_nr=N on the kernel command line.
1402
1403 config X86_PAT
1404         bool
1405         prompt "x86 PAT support"
1406         depends on MTRR
1407         ---help---
1408           Use PAT attributes to setup page level cache control.
1409
1410           PATs are the modern equivalents of MTRRs and are much more
1411           flexible than MTRRs.
1412
1413           Say N here if you see bootup problems (boot crash, boot hang,
1414           spontaneous reboots) or a non-working video driver.
1415
1416           If unsure, say Y.
1417
1418 config EFI
1419         bool "EFI runtime service support"
1420         depends on ACPI
1421         ---help---
1422           This enables the kernel to use EFI runtime services that are
1423           available (such as the EFI variable services).
1424
1425           This option is only useful on systems that have EFI firmware.
1426           In addition, you should use the latest ELILO loader available
1427           at <http://elilo.sourceforge.net> in order to take advantage
1428           of EFI runtime services. However, even with this option, the
1429           resultant kernel should continue to boot on existing non-EFI
1430           platforms.
1431
1432 config SECCOMP
1433         def_bool y
1434         prompt "Enable seccomp to safely compute untrusted bytecode"
1435         ---help---
1436           This kernel feature is useful for number crunching applications
1437           that may need to compute untrusted bytecode during their
1438           execution. By using pipes or other transports made available to
1439           the process as file descriptors supporting the read/write
1440           syscalls, it's possible to isolate those applications in
1441           their own address space using seccomp. Once seccomp is
1442           enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1443           and the task is only allowed to execute a few safe syscalls
1444           defined by each seccomp mode.
1445
1446           If unsure, say Y. Only embedded should say N here.
1447
1448 config CC_STACKPROTECTOR_ALL
1449         bool
1450
1451 config CC_STACKPROTECTOR
1452         bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1453         select CC_STACKPROTECTOR_ALL
1454         ---help---
1455           This option turns on the -fstack-protector GCC feature. This
1456           feature puts, at the beginning of functions, a canary value on
1457           the stack just before the return address, and validates
1458           the value just before actually returning.  Stack based buffer
1459           overflows (that need to overwrite this return address) now also
1460           overwrite the canary, which gets detected and the attack is then
1461           neutralized via a kernel panic.
1462
1463           This feature requires gcc version 4.2 or above, or a distribution
1464           gcc with the feature backported. Older versions are automatically
1465           detected and for those versions, this configuration option is
1466           ignored. (and a warning is printed during bootup)
1467
1468 source kernel/Kconfig.hz
1469
1470 config KEXEC
1471         bool "kexec system call"
1472         ---help---
1473           kexec is a system call that implements the ability to shutdown your
1474           current kernel, and to start another kernel.  It is like a reboot
1475           but it is independent of the system firmware.   And like a reboot
1476           you can start any kernel with it, not just Linux.
1477
1478           The name comes from the similarity to the exec system call.
1479
1480           It is an ongoing process to be certain the hardware in a machine
1481           is properly shutdown, so do not be surprised if this code does not
1482           initially work for you.  It may help to enable device hotplugging
1483           support.  As of this writing the exact hardware interface is
1484           strongly in flux, so no good recommendation can be made.
1485
1486 config CRASH_DUMP
1487         bool "kernel crash dumps"
1488         depends on X86_64 || (X86_32 && HIGHMEM)
1489         ---help---
1490           Generate crash dump after being started by kexec.
1491           This should be normally only set in special crash dump kernels
1492           which are loaded in the main kernel with kexec-tools into
1493           a specially reserved region and then later executed after
1494           a crash by kdump/kexec. The crash dump kernel must be compiled
1495           to a memory address not used by the main kernel or BIOS using
1496           PHYSICAL_START, or it must be built as a relocatable image
1497           (CONFIG_RELOCATABLE=y).
1498           For more details see Documentation/kdump/kdump.txt
1499
1500 config KEXEC_JUMP
1501         bool "kexec jump (EXPERIMENTAL)"
1502         depends on EXPERIMENTAL
1503         depends on KEXEC && HIBERNATION
1504         ---help---
1505           Jump between original kernel and kexeced kernel and invoke
1506           code in physical address mode via KEXEC
1507
1508 config PHYSICAL_START
1509         hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
1510         default "0x1000000"
1511         ---help---
1512           This gives the physical address where the kernel is loaded.
1513
1514           If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1515           bzImage will decompress itself to above physical address and
1516           run from there. Otherwise, bzImage will run from the address where
1517           it has been loaded by the boot loader and will ignore above physical
1518           address.
1519
1520           In normal kdump cases one does not have to set/change this option
1521           as now bzImage can be compiled as a completely relocatable image
1522           (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1523           address. This option is mainly useful for the folks who don't want
1524           to use a bzImage for capturing the crash dump and want to use a
1525           vmlinux instead. vmlinux is not relocatable hence a kernel needs
1526           to be specifically compiled to run from a specific memory area
1527           (normally a reserved region) and this option comes handy.
1528
1529           So if you are using bzImage for capturing the crash dump,
1530           leave the value here unchanged to 0x1000000 and set
1531           CONFIG_RELOCATABLE=y.  Otherwise if you plan to use vmlinux
1532           for capturing the crash dump change this value to start of
1533           the reserved region.  In other words, it can be set based on
1534           the "X" value as specified in the "crashkernel=YM@XM"
1535           command line boot parameter passed to the panic-ed
1536           kernel. Please take a look at Documentation/kdump/kdump.txt
1537           for more details about crash dumps.
1538
1539           Usage of bzImage for capturing the crash dump is recommended as
1540           one does not have to build two kernels. Same kernel can be used
1541           as production kernel and capture kernel. Above option should have
1542           gone away after relocatable bzImage support is introduced. But it
1543           is present because there are users out there who continue to use
1544           vmlinux for dump capture. This option should go away down the
1545           line.
1546
1547           Don't change this unless you know what you are doing.
1548
1549 config RELOCATABLE
1550         bool "Build a relocatable kernel"
1551         default y
1552         ---help---
1553           This builds a kernel image that retains relocation information
1554           so it can be loaded someplace besides the default 1MB.
1555           The relocations tend to make the kernel binary about 10% larger,
1556           but are discarded at runtime.
1557
1558           One use is for the kexec on panic case where the recovery kernel
1559           must live at a different physical address than the primary
1560           kernel.
1561
1562           Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1563           it has been loaded at and the compile time physical address
1564           (CONFIG_PHYSICAL_START) is ignored.
1565
1566 # Relocation on x86-32 needs some additional build support
1567 config X86_NEED_RELOCS
1568         def_bool y
1569         depends on X86_32 && RELOCATABLE
1570
1571 config PHYSICAL_ALIGN
1572         hex
1573         prompt "Alignment value to which kernel should be aligned" if X86_32
1574         default "0x1000000"
1575         range 0x2000 0x1000000
1576         ---help---
1577           This value puts the alignment restrictions on physical address
1578           where kernel is loaded and run from. Kernel is compiled for an
1579           address which meets above alignment restriction.
1580
1581           If bootloader loads the kernel at a non-aligned address and
1582           CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1583           address aligned to above value and run from there.
1584
1585           If bootloader loads the kernel at a non-aligned address and
1586           CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1587           load address and decompress itself to the address it has been
1588           compiled for and run from there. The address for which kernel is
1589           compiled already meets above alignment restrictions. Hence the
1590           end result is that kernel runs from a physical address meeting
1591           above alignment restrictions.
1592
1593           Don't change this unless you know what you are doing.
1594
1595 config HOTPLUG_CPU
1596         bool "Support for hot-pluggable CPUs"
1597         depends on SMP && HOTPLUG
1598         ---help---
1599           Say Y here to allow turning CPUs off and on. CPUs can be
1600           controlled through /sys/devices/system/cpu.
1601           ( Note: power management support will enable this option
1602             automatically on SMP systems. )
1603           Say N if you want to disable CPU hotplug.
1604
1605 config COMPAT_VDSO
1606         def_bool y
1607         prompt "Compat VDSO support"
1608         depends on X86_32 || IA32_EMULATION
1609         ---help---
1610           Map the 32-bit VDSO to the predictable old-style address too.
1611         ---help---
1612           Say N here if you are running a sufficiently recent glibc
1613           version (2.3.3 or later), to remove the high-mapped
1614           VDSO mapping and to exclusively use the randomized VDSO.
1615
1616           If unsure, say Y.
1617
1618 config CMDLINE_BOOL
1619         bool "Built-in kernel command line"
1620         default n
1621         ---help---
1622           Allow for specifying boot arguments to the kernel at
1623           build time.  On some systems (e.g. embedded ones), it is
1624           necessary or convenient to provide some or all of the
1625           kernel boot arguments with the kernel itself (that is,
1626           to not rely on the boot loader to provide them.)
1627
1628           To compile command line arguments into the kernel,
1629           set this option to 'Y', then fill in the
1630           the boot arguments in CONFIG_CMDLINE.
1631
1632           Systems with fully functional boot loaders (i.e. non-embedded)
1633           should leave this option set to 'N'.
1634
1635 config CMDLINE
1636         string "Built-in kernel command string"
1637         depends on CMDLINE_BOOL
1638         default ""
1639         ---help---
1640           Enter arguments here that should be compiled into the kernel
1641           image and used at boot time.  If the boot loader provides a
1642           command line at boot time, it is appended to this string to
1643           form the full kernel command line, when the system boots.
1644
1645           However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1646           change this behavior.
1647
1648           In most cases, the command line (whether built-in or provided
1649           by the boot loader) should specify the device for the root
1650           file system.
1651
1652 config CMDLINE_OVERRIDE
1653         bool "Built-in command line overrides boot loader arguments"
1654         default n
1655         depends on CMDLINE_BOOL
1656         ---help---
1657           Set this option to 'Y' to have the kernel ignore the boot loader
1658           command line, and use ONLY the built-in command line.
1659
1660           This is used to work around broken boot loaders.  This should
1661           be set to 'N' under normal conditions.
1662
1663 endmenu
1664
1665 config ARCH_ENABLE_MEMORY_HOTPLUG
1666         def_bool y
1667         depends on X86_64 || (X86_32 && HIGHMEM)
1668
1669 config ARCH_ENABLE_MEMORY_HOTREMOVE
1670         def_bool y
1671         depends on MEMORY_HOTPLUG
1672
1673 config HAVE_ARCH_EARLY_PFN_TO_NID
1674         def_bool X86_64
1675         depends on NUMA
1676
1677 menu "Power management and ACPI options"
1678
1679 config ARCH_HIBERNATION_HEADER
1680         def_bool y
1681         depends on X86_64 && HIBERNATION
1682
1683 source "kernel/power/Kconfig"
1684
1685 source "drivers/acpi/Kconfig"
1686
1687 config X86_APM_BOOT
1688         bool
1689         default y
1690         depends on APM || APM_MODULE
1691
1692 menuconfig APM
1693         tristate "APM (Advanced Power Management) BIOS support"
1694         depends on X86_32 && PM_SLEEP
1695         ---help---
1696           APM is a BIOS specification for saving power using several different
1697           techniques. This is mostly useful for battery powered laptops with
1698           APM compliant BIOSes. If you say Y here, the system time will be
1699           reset after a RESUME operation, the /proc/apm device will provide
1700           battery status information, and user-space programs will receive
1701           notification of APM "events" (e.g. battery status change).
1702
1703           If you select "Y" here, you can disable actual use of the APM
1704           BIOS by passing the "apm=off" option to the kernel at boot time.
1705
1706           Note that the APM support is almost completely disabled for
1707           machines with more than one CPU.
1708
1709           In order to use APM, you will need supporting software. For location
1710           and more information, read <file:Documentation/power/pm.txt> and the
1711           Battery Powered Linux mini-HOWTO, available from
1712           <http://www.tldp.org/docs.html#howto>.
1713
1714           This driver does not spin down disk drives (see the hdparm(8)
1715           manpage ("man 8 hdparm") for that), and it doesn't turn off
1716           VESA-compliant "green" monitors.
1717
1718           This driver does not support the TI 4000M TravelMate and the ACER
1719           486/DX4/75 because they don't have compliant BIOSes. Many "green"
1720           desktop machines also don't have compliant BIOSes, and this driver
1721           may cause those machines to panic during the boot phase.
1722
1723           Generally, if you don't have a battery in your machine, there isn't
1724           much point in using this driver and you should say N. If you get
1725           random kernel OOPSes or reboots that don't seem to be related to
1726           anything, try disabling/enabling this option (or disabling/enabling
1727           APM in your BIOS).
1728
1729           Some other things you should try when experiencing seemingly random,
1730           "weird" problems:
1731
1732           1) make sure that you have enough swap space and that it is
1733           enabled.
1734           2) pass the "no-hlt" option to the kernel
1735           3) switch on floating point emulation in the kernel and pass
1736           the "no387" option to the kernel
1737           4) pass the "floppy=nodma" option to the kernel
1738           5) pass the "mem=4M" option to the kernel (thereby disabling
1739           all but the first 4 MB of RAM)
1740           6) make sure that the CPU is not over clocked.
1741           7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1742           8) disable the cache from your BIOS settings
1743           9) install a fan for the video card or exchange video RAM
1744           10) install a better fan for the CPU
1745           11) exchange RAM chips
1746           12) exchange the motherboard.
1747
1748           To compile this driver as a module, choose M here: the
1749           module will be called apm.
1750
1751 if APM
1752
1753 config APM_IGNORE_USER_SUSPEND
1754         bool "Ignore USER SUSPEND"
1755         ---help---
1756           This option will ignore USER SUSPEND requests. On machines with a
1757           compliant APM BIOS, you want to say N. However, on the NEC Versa M
1758           series notebooks, it is necessary to say Y because of a BIOS bug.
1759
1760 config APM_DO_ENABLE
1761         bool "Enable PM at boot time"
1762         ---help---
1763           Enable APM features at boot time. From page 36 of the APM BIOS
1764           specification: "When disabled, the APM BIOS does not automatically
1765           power manage devices, enter the Standby State, enter the Suspend
1766           State, or take power saving steps in response to CPU Idle calls."
1767           This driver will make CPU Idle calls when Linux is idle (unless this
1768           feature is turned off -- see "Do CPU IDLE calls", below). This
1769           should always save battery power, but more complicated APM features
1770           will be dependent on your BIOS implementation. You may need to turn
1771           this option off if your computer hangs at boot time when using APM
1772           support, or if it beeps continuously instead of suspending. Turn
1773           this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1774           T400CDT. This is off by default since most machines do fine without
1775           this feature.
1776
1777 config APM_CPU_IDLE
1778         bool "Make CPU Idle calls when idle"
1779         ---help---
1780           Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1781           On some machines, this can activate improved power savings, such as
1782           a slowed CPU clock rate, when the machine is idle. These idle calls
1783           are made after the idle loop has run for some length of time (e.g.,
1784           333 mS). On some machines, this will cause a hang at boot time or
1785           whenever the CPU becomes idle. (On machines with more than one CPU,
1786           this option does nothing.)
1787
1788 config APM_DISPLAY_BLANK
1789         bool "Enable console blanking using APM"
1790         ---help---
1791           Enable console blanking using the APM. Some laptops can use this to
1792           turn off the LCD backlight when the screen blanker of the Linux
1793           virtual console blanks the screen. Note that this is only used by
1794           the virtual console screen blanker, and won't turn off the backlight
1795           when using the X Window system. This also doesn't have anything to
1796           do with your VESA-compliant power-saving monitor. Further, this
1797           option doesn't work for all laptops -- it might not turn off your
1798           backlight at all, or it might print a lot of errors to the console,
1799           especially if you are using gpm.
1800
1801 config APM_ALLOW_INTS
1802         bool "Allow interrupts during APM BIOS calls"
1803         ---help---
1804           Normally we disable external interrupts while we are making calls to
1805           the APM BIOS as a measure to lessen the effects of a badly behaving
1806           BIOS implementation.  The BIOS should reenable interrupts if it
1807           needs to.  Unfortunately, some BIOSes do not -- especially those in
1808           many of the newer IBM Thinkpads.  If you experience hangs when you
1809           suspend, try setting this to Y.  Otherwise, say N.
1810
1811 endif # APM
1812
1813 source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1814
1815 source "drivers/cpuidle/Kconfig"
1816
1817 source "drivers/idle/Kconfig"
1818
1819 endmenu
1820
1821
1822 menu "Bus options (PCI etc.)"
1823
1824 config PCI
1825         bool "PCI support"
1826         default y
1827         select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
1828         ---help---
1829           Find out whether you have a PCI motherboard. PCI is the name of a
1830           bus system, i.e. the way the CPU talks to the other stuff inside
1831           your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1832           VESA. If you have PCI, say Y, otherwise N.
1833
1834 choice
1835         prompt "PCI access mode"
1836         depends on X86_32 && PCI
1837         default PCI_GOANY
1838         ---help---
1839           On PCI systems, the BIOS can be used to detect the PCI devices and
1840           determine their configuration. However, some old PCI motherboards
1841           have BIOS bugs and may crash if this is done. Also, some embedded
1842           PCI-based systems don't have any BIOS at all. Linux can also try to
1843           detect the PCI hardware directly without using the BIOS.
1844
1845           With this option, you can specify how Linux should detect the
1846           PCI devices. If you choose "BIOS", the BIOS will be used,
1847           if you choose "Direct", the BIOS won't be used, and if you
1848           choose "MMConfig", then PCI Express MMCONFIG will be used.
1849           If you choose "Any", the kernel will try MMCONFIG, then the
1850           direct access method and falls back to the BIOS if that doesn't
1851           work. If unsure, go with the default, which is "Any".
1852
1853 config PCI_GOBIOS
1854         bool "BIOS"
1855
1856 config PCI_GOMMCONFIG
1857         bool "MMConfig"
1858
1859 config PCI_GODIRECT
1860         bool "Direct"
1861
1862 config PCI_GOOLPC
1863         bool "OLPC"
1864         depends on OLPC
1865
1866 config PCI_GOANY
1867         bool "Any"
1868
1869 endchoice
1870
1871 config PCI_BIOS
1872         def_bool y
1873         depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
1874
1875 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1876 config PCI_DIRECT
1877         def_bool y
1878         depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
1879
1880 config PCI_MMCONFIG
1881         def_bool y
1882         depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1883
1884 config PCI_OLPC
1885         def_bool y
1886         depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
1887
1888 config PCI_DOMAINS
1889         def_bool y
1890         depends on PCI
1891
1892 config PCI_MMCONFIG
1893         bool "Support mmconfig PCI config space access"
1894         depends on X86_64 && PCI && ACPI
1895
1896 config DMAR
1897         bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
1898         depends on PCI_MSI && ACPI && EXPERIMENTAL
1899         help
1900           DMA remapping (DMAR) devices support enables independent address
1901           translations for Direct Memory Access (DMA) from devices.
1902           These DMA remapping devices are reported via ACPI tables
1903           and include PCI device scope covered by these DMA
1904           remapping devices.
1905
1906 config DMAR_DEFAULT_ON
1907         def_bool y
1908         prompt "Enable DMA Remapping Devices by default"
1909         depends on DMAR
1910         help
1911           Selecting this option will enable a DMAR device at boot time if
1912           one is found. If this option is not selected, DMAR support can
1913           be enabled by passing intel_iommu=on to the kernel. It is
1914           recommended you say N here while the DMAR code remains
1915           experimental.
1916
1917 config DMAR_BROKEN_GFX_WA
1918         def_bool n
1919         prompt "Workaround broken graphics drivers (going away soon)"
1920         depends on DMAR
1921         ---help---
1922           Current Graphics drivers tend to use physical address
1923           for DMA and avoid using DMA APIs. Setting this config
1924           option permits the IOMMU driver to set a unity map for
1925           all the OS-visible memory. Hence the driver can continue
1926           to use physical addresses for DMA, at least until this
1927           option is removed in the 2.6.32 kernel.
1928
1929 config DMAR_FLOPPY_WA
1930         def_bool y
1931         depends on DMAR
1932         ---help---
1933           Floppy disk drivers are known to bypass DMA API calls
1934           thereby failing to work when IOMMU is enabled. This
1935           workaround will setup a 1:1 mapping for the first
1936           16MiB to make floppy (an ISA device) work.
1937
1938 config INTR_REMAP
1939         bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1940         depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
1941         ---help---
1942           Supports Interrupt remapping for IO-APIC and MSI devices.
1943           To use x2apic mode in the CPU's which support x2APIC enhancements or
1944           to support platforms with CPU's having > 8 bit APIC ID, say Y.
1945
1946 source "drivers/pci/pcie/Kconfig"
1947
1948 source "drivers/pci/Kconfig"
1949
1950 # x86_64 have no ISA slots, but do have ISA-style DMA.
1951 config ISA_DMA_API
1952         def_bool y
1953
1954 if X86_32
1955
1956 config ISA
1957         bool "ISA support"
1958         ---help---
1959           Find out whether you have ISA slots on your motherboard.  ISA is the
1960           name of a bus system, i.e. the way the CPU talks to the other stuff
1961           inside your box.  Other bus systems are PCI, EISA, MicroChannel
1962           (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
1963           newer boards don't support it.  If you have ISA, say Y, otherwise N.
1964
1965 config EISA
1966         bool "EISA support"
1967         depends on ISA
1968         ---help---
1969           The Extended Industry Standard Architecture (EISA) bus was
1970           developed as an open alternative to the IBM MicroChannel bus.
1971
1972           The EISA bus provided some of the features of the IBM MicroChannel
1973           bus while maintaining backward compatibility with cards made for
1974           the older ISA bus.  The EISA bus saw limited use between 1988 and
1975           1995 when it was made obsolete by the PCI bus.
1976
1977           Say Y here if you are building a kernel for an EISA-based machine.
1978
1979           Otherwise, say N.
1980
1981 source "drivers/eisa/Kconfig"
1982
1983 config MCA
1984         bool "MCA support"
1985         ---help---
1986           MicroChannel Architecture is found in some IBM PS/2 machines and
1987           laptops.  It is a bus system similar to PCI or ISA. See
1988           <file:Documentation/mca.txt> (and especially the web page given
1989           there) before attempting to build an MCA bus kernel.
1990
1991 source "drivers/mca/Kconfig"
1992
1993 config SCx200
1994         tristate "NatSemi SCx200 support"
1995         ---help---
1996           This provides basic support for National Semiconductor's
1997           (now AMD's) Geode processors.  The driver probes for the
1998           PCI-IDs of several on-chip devices, so its a good dependency
1999           for other scx200_* drivers.
2000
2001           If compiled as a module, the driver is named scx200.
2002
2003 config SCx200HR_TIMER
2004         tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2005         depends on SCx200 && GENERIC_TIME
2006         default y
2007         ---help---
2008           This driver provides a clocksource built upon the on-chip
2009           27MHz high-resolution timer.  Its also a workaround for
2010           NSC Geode SC-1100's buggy TSC, which loses time when the
2011           processor goes idle (as is done by the scheduler).  The
2012           other workaround is idle=poll boot option.
2013
2014 config GEODE_MFGPT_TIMER
2015         def_bool y
2016         prompt "Geode Multi-Function General Purpose Timer (MFGPT) events"
2017         depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS
2018         ---help---
2019           This driver provides a clock event source based on the MFGPT
2020           timer(s) in the CS5535 and CS5536 companion chip for the geode.
2021           MFGPTs have a better resolution and max interval than the
2022           generic PIT, and are suitable for use as high-res timers.
2023
2024 config OLPC
2025         bool "One Laptop Per Child support"
2026         default n
2027         ---help---
2028           Add support for detecting the unique features of the OLPC
2029           XO hardware.
2030
2031 endif # X86_32
2032
2033 config K8_NB
2034         def_bool y
2035         depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA)))
2036
2037 source "drivers/pcmcia/Kconfig"
2038
2039 source "drivers/pci/hotplug/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 endmenu
2076
2077
2078 config HAVE_ATOMIC_IOMAP
2079         def_bool y
2080         depends on X86_32
2081
2082 source "net/Kconfig"
2083
2084 source "drivers/Kconfig"
2085
2086 source "drivers/firmware/Kconfig"
2087
2088 source "fs/Kconfig"
2089
2090 source "arch/x86/Kconfig.debug"
2091
2092 source "security/Kconfig"
2093
2094 source "crypto/Kconfig"
2095
2096 source "arch/x86/kvm/Kconfig"
2097
2098 source "lib/Kconfig"