1# x86 configuration 2mainmenu "Linux Kernel Configuration for x86" 3 4# Select 32 or 64 bit 5config 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 12config X86_32 13 def_bool !64BIT 14 15config X86_64 16 def_bool 64BIT 17 18### Arch settings 19config 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_IOREMAP_PROT 28 select HAVE_KPROBES 29 select ARCH_WANT_OPTIONAL_GPIOLIB 30 select ARCH_WANT_FRAME_POINTERS 31 select HAVE_KRETPROBES 32 select HAVE_FTRACE_MCOUNT_RECORD 33 select HAVE_DYNAMIC_FTRACE 34 select HAVE_FUNCTION_TRACER 35 select HAVE_FUNCTION_GRAPH_TRACER 36 select HAVE_FUNCTION_TRACE_MCOUNT_TEST 37 select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE 38 select HAVE_FTRACE_SYSCALLS 39 select HAVE_KVM 40 select HAVE_ARCH_KGDB 41 select HAVE_ARCH_TRACEHOOK 42 select HAVE_GENERIC_DMA_COHERENT if X86_32 43 select HAVE_EFFICIENT_UNALIGNED_ACCESS 44 select USER_STACKTRACE_SUPPORT 45 select HAVE_DMA_API_DEBUG 46 select HAVE_KERNEL_GZIP 47 select HAVE_KERNEL_BZIP2 48 select HAVE_KERNEL_LZMA 49 50config ARCH_DEFCONFIG 51 string 52 default "arch/x86/configs/i386_defconfig" if X86_32 53 default "arch/x86/configs/x86_64_defconfig" if X86_64 54 55config GENERIC_TIME 56 def_bool y 57 58config GENERIC_CMOS_UPDATE 59 def_bool y 60 61config CLOCKSOURCE_WATCHDOG 62 def_bool y 63 64config GENERIC_CLOCKEVENTS 65 def_bool y 66 67config GENERIC_CLOCKEVENTS_BROADCAST 68 def_bool y 69 depends on X86_64 || (X86_32 && X86_LOCAL_APIC) 70 71config LOCKDEP_SUPPORT 72 def_bool y 73 74config STACKTRACE_SUPPORT 75 def_bool y 76 77config HAVE_LATENCYTOP_SUPPORT 78 def_bool y 79 80config FAST_CMPXCHG_LOCAL 81 bool 82 default y 83 84config MMU 85 def_bool y 86 87config ZONE_DMA 88 def_bool y 89 90config SBUS 91 bool 92 93config GENERIC_ISA_DMA 94 def_bool y 95 96config GENERIC_IOMAP 97 def_bool y 98 99config GENERIC_BUG 100 def_bool y 101 depends on BUG 102 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 103 104config GENERIC_BUG_RELATIVE_POINTERS 105 bool 106 107config GENERIC_HWEIGHT 108 def_bool y 109 110config GENERIC_GPIO 111 bool 112 113config ARCH_MAY_HAVE_PC_FDC 114 def_bool y 115 116config RWSEM_GENERIC_SPINLOCK 117 def_bool !X86_XADD 118 119config RWSEM_XCHGADD_ALGORITHM 120 def_bool X86_XADD 121 122config ARCH_HAS_CPU_IDLE_WAIT 123 def_bool y 124 125config GENERIC_CALIBRATE_DELAY 126 def_bool y 127 128config GENERIC_TIME_VSYSCALL 129 bool 130 default X86_64 131 132config ARCH_HAS_CPU_RELAX 133 def_bool y 134 135config ARCH_HAS_DEFAULT_IDLE 136 def_bool y 137 138config ARCH_HAS_CACHE_LINE_SIZE 139 def_bool y 140 141config HAVE_SETUP_PER_CPU_AREA 142 def_bool y 143 144config HAVE_DYNAMIC_PER_CPU_AREA 145 def_bool y 146 147config HAVE_CPUMASK_OF_CPU_MAP 148 def_bool X86_64_SMP 149 150config ARCH_HIBERNATION_POSSIBLE 151 def_bool y 152 153config ARCH_SUSPEND_POSSIBLE 154 def_bool y 155 156config ZONE_DMA32 157 bool 158 default X86_64 159 160config ARCH_POPULATES_NODE_MAP 161 def_bool y 162 163config AUDIT_ARCH 164 bool 165 default X86_64 166 167config ARCH_SUPPORTS_OPTIMIZED_INLINING 168 def_bool y 169 170config ARCH_SUPPORTS_DEBUG_PAGEALLOC 171 def_bool y 172 173# Use the generic interrupt handling code in kernel/irq/: 174config GENERIC_HARDIRQS 175 bool 176 default y 177 178config GENERIC_HARDIRQS_NO__DO_IRQ 179 def_bool y 180 181config GENERIC_IRQ_PROBE 182 bool 183 default y 184 185config GENERIC_PENDING_IRQ 186 bool 187 depends on GENERIC_HARDIRQS && SMP 188 default y 189 190config USE_GENERIC_SMP_HELPERS 191 def_bool y 192 depends on SMP 193 194config X86_32_SMP 195 def_bool y 196 depends on X86_32 && SMP 197 198config X86_64_SMP 199 def_bool y 200 depends on X86_64 && SMP 201 202config X86_HT 203 bool 204 depends on SMP 205 default y 206 207config X86_TRAMPOLINE 208 bool 209 depends on SMP || (64BIT && ACPI_SLEEP) 210 default y 211 212config X86_32_LAZY_GS 213 def_bool y 214 depends on X86_32 && !CC_STACKPROTECTOR 215 216config KTIME_SCALAR 217 def_bool X86_32 218source "init/Kconfig" 219source "kernel/Kconfig.freezer" 220 221menu "Processor type and features" 222 223source "kernel/time/Kconfig" 224 225config SMP 226 bool "Symmetric multi-processing support" 227 ---help--- 228 This enables support for systems with more than one CPU. If you have 229 a system with only one CPU, like most personal computers, say N. If 230 you have a system with more than one CPU, say Y. 231 232 If you say N here, the kernel will run on single and multiprocessor 233 machines, but will use only one CPU of a multiprocessor machine. If 234 you say Y here, the kernel will run on many, but not all, 235 singleprocessor machines. On a singleprocessor machine, the kernel 236 will run faster if you say N here. 237 238 Note that if you say Y here and choose architecture "586" or 239 "Pentium" under "Processor family", the kernel will not work on 486 240 architectures. Similarly, multiprocessor kernels for the "PPro" 241 architecture may not work on all Pentium based boards. 242 243 People using multiprocessor machines who say Y here should also say 244 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 245 Management" code will be disabled if you say Y here. 246 247 See also <file:Documentation/i386/IO-APIC.txt>, 248 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 249 <http://www.tldp.org/docs.html#howto>. 250 251 If you don't know what to do here, say N. 252 253config X86_X2APIC 254 bool "Support x2apic" 255 depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP 256 ---help--- 257 This enables x2apic support on CPUs that have this feature. 258 259 This allows 32-bit apic IDs (so it can support very large systems), 260 and accesses the local apic via MSRs not via mmio. 261 262 If you don't know what to do here, say N. 263 264config SPARSE_IRQ 265 bool "Support sparse irq numbering" 266 depends on PCI_MSI || HT_IRQ 267 ---help--- 268 This enables support for sparse irqs. This is useful for distro 269 kernels that want to define a high CONFIG_NR_CPUS value but still 270 want to have low kernel memory footprint on smaller machines. 271 272 ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread 273 out the irq_desc[] array in a more NUMA-friendly way. ) 274 275 If you don't know what to do here, say N. 276 277config NUMA_MIGRATE_IRQ_DESC 278 bool "Move irq desc when changing irq smp_affinity" 279 depends on SPARSE_IRQ && NUMA 280 depends on BROKEN 281 default n 282 ---help--- 283 This enables moving irq_desc to cpu/node that irq will use handled. 284 285 If you don't know what to do here, say N. 286 287config X86_MPPARSE 288 bool "Enable MPS table" if ACPI 289 default y 290 depends on X86_LOCAL_APIC 291 ---help--- 292 For old smp systems that do not have proper acpi support. Newer systems 293 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 294 295config X86_BIGSMP 296 bool "Support for big SMP systems with more than 8 CPUs" 297 depends on X86_32 && SMP 298 ---help--- 299 This option is needed for the systems that have more than 8 CPUs 300 301if X86_32 302config X86_EXTENDED_PLATFORM 303 bool "Support for extended (non-PC) x86 platforms" 304 default y 305 ---help--- 306 If you disable this option then the kernel will only support 307 standard PC platforms. (which covers the vast majority of 308 systems out there.) 309 310 If you enable this option then you'll be able to select support 311 for the following (non-PC) 32 bit x86 platforms: 312 AMD Elan 313 NUMAQ (IBM/Sequent) 314 RDC R-321x SoC 315 SGI 320/540 (Visual Workstation) 316 Summit/EXA (IBM x440) 317 Unisys ES7000 IA32 series 318 319 If you have one of these systems, or if you want to build a 320 generic distribution kernel, say Y here - otherwise say N. 321endif 322 323if X86_64 324config X86_EXTENDED_PLATFORM 325 bool "Support for extended (non-PC) x86 platforms" 326 default y 327 ---help--- 328 If you disable this option then the kernel will only support 329 standard PC platforms. (which covers the vast majority of 330 systems out there.) 331 332 If you enable this option then you'll be able to select support 333 for the following (non-PC) 64 bit x86 platforms: 334 ScaleMP vSMP 335 SGI Ultraviolet 336 337 If you have one of these systems, or if you want to build a 338 generic distribution kernel, say Y here - otherwise say N. 339endif 340# This is an alphabetically sorted list of 64 bit extended platforms 341# Please maintain the alphabetic order if and when there are additions 342 343config X86_VSMP 344 bool "ScaleMP vSMP" 345 select PARAVIRT 346 depends on X86_64 && PCI 347 depends on X86_EXTENDED_PLATFORM 348 ---help--- 349 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 350 supposed to run on these EM64T-based machines. Only choose this option 351 if you have one of these machines. 352 353config X86_UV 354 bool "SGI Ultraviolet" 355 depends on X86_64 356 depends on X86_EXTENDED_PLATFORM 357 depends on NUMA 358 select X86_X2APIC 359 ---help--- 360 This option is needed in order to support SGI Ultraviolet systems. 361 If you don't have one of these, you should say N here. 362 363# Following is an alphabetically sorted list of 32 bit extended platforms 364# Please maintain the alphabetic order if and when there are additions 365 366config X86_ELAN 367 bool "AMD Elan" 368 depends on X86_32 369 depends on X86_EXTENDED_PLATFORM 370 ---help--- 371 Select this for an AMD Elan processor. 372 373 Do not use this option for K6/Athlon/Opteron processors! 374 375 If unsure, choose "PC-compatible" instead. 376 377config X86_RDC321X 378 bool "RDC R-321x SoC" 379 depends on X86_32 380 depends on X86_EXTENDED_PLATFORM 381 select M486 382 select X86_REBOOTFIXUPS 383 ---help--- 384 This option is needed for RDC R-321x system-on-chip, also known 385 as R-8610-(G). 386 If you don't have one of these chips, you should say N here. 387 388config X86_32_NON_STANDARD 389 bool "Support non-standard 32-bit SMP architectures" 390 depends on X86_32 && SMP 391 depends on X86_EXTENDED_PLATFORM 392 ---help--- 393 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default 394 subarchitectures. It is intended for a generic binary kernel. 395 if you select them all, kernel will probe it one by one. and will 396 fallback to default. 397 398# Alphabetically sorted list of Non standard 32 bit platforms 399 400config X86_NUMAQ 401 bool "NUMAQ (IBM/Sequent)" 402 depends on X86_32_NON_STANDARD 403 select NUMA 404 select X86_MPPARSE 405 ---help--- 406 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent) 407 NUMA multiquad box. This changes the way that processors are 408 bootstrapped, and uses Clustered Logical APIC addressing mode instead 409 of Flat Logical. You will need a new lynxer.elf file to flash your 410 firmware with - send email to <Martin.Bligh@us.ibm.com>. 411 412config X86_VISWS 413 bool "SGI 320/540 (Visual Workstation)" 414 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT 415 depends on X86_32_NON_STANDARD 416 ---help--- 417 The SGI Visual Workstation series is an IA32-based workstation 418 based on SGI systems chips with some legacy PC hardware attached. 419 420 Say Y here to create a kernel to run on the SGI 320 or 540. 421 422 A kernel compiled for the Visual Workstation will run on general 423 PCs as well. See <file:Documentation/sgi-visws.txt> for details. 424 425config X86_SUMMIT 426 bool "Summit/EXA (IBM x440)" 427 depends on X86_32_NON_STANDARD 428 ---help--- 429 This option is needed for IBM systems that use the Summit/EXA chipset. 430 In particular, it is needed for the x440. 431 432config X86_ES7000 433 bool "Unisys ES7000 IA32 series" 434 depends on X86_32_NON_STANDARD && X86_BIGSMP 435 ---help--- 436 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is 437 supposed to run on an IA32-based Unisys ES7000 system. 438 439config SCHED_OMIT_FRAME_POINTER 440 def_bool y 441 prompt "Single-depth WCHAN output" 442 depends on X86 443 ---help--- 444 Calculate simpler /proc/<PID>/wchan values. If this option 445 is disabled then wchan values will recurse back to the 446 caller function. This provides more accurate wchan values, 447 at the expense of slightly more scheduling overhead. 448 449 If in doubt, say "Y". 450 451menuconfig PARAVIRT_GUEST 452 bool "Paravirtualized guest support" 453 ---help--- 454 Say Y here to get to see options related to running Linux under 455 various hypervisors. This option alone does not add any kernel code. 456 457 If you say N, all options in this submenu will be skipped and disabled. 458 459if PARAVIRT_GUEST 460 461source "arch/x86/xen/Kconfig" 462 463config VMI 464 bool "VMI Guest support" 465 select PARAVIRT 466 depends on X86_32 467 ---help--- 468 VMI provides a paravirtualized interface to the VMware ESX server 469 (it could be used by other hypervisors in theory too, but is not 470 at the moment), by linking the kernel to a GPL-ed ROM module 471 provided by the hypervisor. 472 473config KVM_CLOCK 474 bool "KVM paravirtualized clock" 475 select PARAVIRT 476 select PARAVIRT_CLOCK 477 ---help--- 478 Turning on this option will allow you to run a paravirtualized clock 479 when running over the KVM hypervisor. Instead of relying on a PIT 480 (or probably other) emulation by the underlying device model, the host 481 provides the guest with timing infrastructure such as time of day, and 482 system time 483 484config KVM_GUEST 485 bool "KVM Guest support" 486 select PARAVIRT 487 ---help--- 488 This option enables various optimizations for running under the KVM 489 hypervisor. 490 491source "arch/x86/lguest/Kconfig" 492 493config PARAVIRT 494 bool "Enable paravirtualization code" 495 ---help--- 496 This changes the kernel so it can modify itself when it is run 497 under a hypervisor, potentially improving performance significantly 498 over full virtualization. However, when run without a hypervisor 499 the kernel is theoretically slower and slightly larger. 500 501config PARAVIRT_CLOCK 502 bool 503 default n 504 505endif 506 507config PARAVIRT_DEBUG 508 bool "paravirt-ops debugging" 509 depends on PARAVIRT && DEBUG_KERNEL 510 ---help--- 511 Enable to debug paravirt_ops internals. Specifically, BUG if 512 a paravirt_op is missing when it is called. 513 514config MEMTEST 515 bool "Memtest" 516 ---help--- 517 This option adds a kernel parameter 'memtest', which allows memtest 518 to be set. 519 memtest=0, mean disabled; -- default 520 memtest=1, mean do 1 test pattern; 521 ... 522 memtest=4, mean do 4 test patterns. 523 If you are unsure how to answer this question, answer N. 524 525config X86_SUMMIT_NUMA 526 def_bool y 527 depends on X86_32 && NUMA && X86_32_NON_STANDARD 528 529config X86_CYCLONE_TIMER 530 def_bool y 531 depends on X86_32_NON_STANDARD 532 533source "arch/x86/Kconfig.cpu" 534 535config HPET_TIMER 536 def_bool X86_64 537 prompt "HPET Timer Support" if X86_32 538 ---help--- 539 Use the IA-PC HPET (High Precision Event Timer) to manage 540 time in preference to the PIT and RTC, if a HPET is 541 present. 542 HPET is the next generation timer replacing legacy 8254s. 543 The HPET provides a stable time base on SMP 544 systems, unlike the TSC, but it is more expensive to access, 545 as it is off-chip. You can find the HPET spec at 546 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>. 547 548 You can safely choose Y here. However, HPET will only be 549 activated if the platform and the BIOS support this feature. 550 Otherwise the 8254 will be used for timing services. 551 552 Choose N to continue using the legacy 8254 timer. 553 554config HPET_EMULATE_RTC 555 def_bool y 556 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 557 558# Mark as embedded because too many people got it wrong. 559# The code disables itself when not needed. 560config DMI 561 default y 562 bool "Enable DMI scanning" if EMBEDDED 563 ---help--- 564 Enabled scanning of DMI to identify machine quirks. Say Y 565 here unless you have verified that your setup is not 566 affected by entries in the DMI blacklist. Required by PNP 567 BIOS code. 568 569config GART_IOMMU 570 bool "GART IOMMU support" if EMBEDDED 571 default y 572 select SWIOTLB 573 select AGP 574 depends on X86_64 && PCI 575 ---help--- 576 Support for full DMA access of devices with 32bit memory access only 577 on systems with more than 3GB. This is usually needed for USB, 578 sound, many IDE/SATA chipsets and some other devices. 579 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART 580 based hardware IOMMU and a software bounce buffer based IOMMU used 581 on Intel systems and as fallback. 582 The code is only active when needed (enough memory and limited 583 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified 584 too. 585 586config CALGARY_IOMMU 587 bool "IBM Calgary IOMMU support" 588 select SWIOTLB 589 depends on X86_64 && PCI && EXPERIMENTAL 590 ---help--- 591 Support for hardware IOMMUs in IBM's xSeries x366 and x460 592 systems. Needed to run systems with more than 3GB of memory 593 properly with 32-bit PCI devices that do not support DAC 594 (Double Address Cycle). Calgary also supports bus level 595 isolation, where all DMAs pass through the IOMMU. This 596 prevents them from going anywhere except their intended 597 destination. This catches hard-to-find kernel bugs and 598 mis-behaving drivers and devices that do not use the DMA-API 599 properly to set up their DMA buffers. The IOMMU can be 600 turned off at boot time with the iommu=off parameter. 601 Normally the kernel will make the right choice by itself. 602 If unsure, say Y. 603 604config CALGARY_IOMMU_ENABLED_BY_DEFAULT 605 def_bool y 606 prompt "Should Calgary be enabled by default?" 607 depends on CALGARY_IOMMU 608 ---help--- 609 Should Calgary be enabled by default? if you choose 'y', Calgary 610 will be used (if it exists). If you choose 'n', Calgary will not be 611 used even if it exists. If you choose 'n' and would like to use 612 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 613 If unsure, say Y. 614 615config AMD_IOMMU 616 bool "AMD IOMMU support" 617 select SWIOTLB 618 select PCI_MSI 619 depends on X86_64 && PCI && ACPI 620 ---help--- 621 With this option you can enable support for AMD IOMMU hardware in 622 your system. An IOMMU is a hardware component which provides 623 remapping of DMA memory accesses from devices. With an AMD IOMMU you 624 can isolate the the DMA memory of different devices and protect the 625 system from misbehaving device drivers or hardware. 626 627 You can find out if your system has an AMD IOMMU if you look into 628 your BIOS for an option to enable it or if you have an IVRS ACPI 629 table. 630 631config AMD_IOMMU_STATS 632 bool "Export AMD IOMMU statistics to debugfs" 633 depends on AMD_IOMMU 634 select DEBUG_FS 635 ---help--- 636 This option enables code in the AMD IOMMU driver to collect various 637 statistics about whats happening in the driver and exports that 638 information to userspace via debugfs. 639 If unsure, say N. 640 641# need this always selected by IOMMU for the VIA workaround 642config SWIOTLB 643 def_bool y if X86_64 644 ---help--- 645 Support for software bounce buffers used on x86-64 systems 646 which don't have a hardware IOMMU (e.g. the current generation 647 of Intel's x86-64 CPUs). Using this PCI devices which can only 648 access 32-bits of memory can be used on systems with more than 649 3 GB of memory. If unsure, say Y. 650 651config IOMMU_HELPER 652 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU) 653 654config IOMMU_API 655 def_bool (AMD_IOMMU || DMAR) 656 657config MAXSMP 658 bool "Configure Maximum number of SMP Processors and NUMA Nodes" 659 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL 660 select CPUMASK_OFFSTACK 661 default n 662 ---help--- 663 Configure maximum number of CPUS and NUMA Nodes for this architecture. 664 If unsure, say N. 665 666config NR_CPUS 667 int "Maximum number of CPUs" if SMP && !MAXSMP 668 range 2 8 if SMP && X86_32 && !X86_BIGSMP 669 range 2 512 if SMP && !MAXSMP 670 default "1" if !SMP 671 default "4096" if MAXSMP 672 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000) 673 default "8" if SMP 674 ---help--- 675 This allows you to specify the maximum number of CPUs which this 676 kernel will support. The maximum supported value is 512 and the 677 minimum value which makes sense is 2. 678 679 This is purely to save memory - each supported CPU adds 680 approximately eight kilobytes to the kernel image. 681 682config SCHED_SMT 683 bool "SMT (Hyperthreading) scheduler support" 684 depends on X86_HT 685 ---help--- 686 SMT scheduler support improves the CPU scheduler's decision making 687 when dealing with Intel Pentium 4 chips with HyperThreading at a 688 cost of slightly increased overhead in some places. If unsure say 689 N here. 690 691config SCHED_MC 692 def_bool y 693 prompt "Multi-core scheduler support" 694 depends on X86_HT 695 ---help--- 696 Multi-core scheduler support improves the CPU scheduler's decision 697 making when dealing with multi-core CPU chips at a cost of slightly 698 increased overhead in some places. If unsure say N here. 699 700source "kernel/Kconfig.preempt" 701 702config X86_UP_APIC 703 bool "Local APIC support on uniprocessors" 704 depends on X86_32 && !SMP && !X86_32_NON_STANDARD 705 ---help--- 706 A local APIC (Advanced Programmable Interrupt Controller) is an 707 integrated interrupt controller in the CPU. If you have a single-CPU 708 system which has a processor with a local APIC, you can say Y here to 709 enable and use it. If you say Y here even though your machine doesn't 710 have a local APIC, then the kernel will still run with no slowdown at 711 all. The local APIC supports CPU-generated self-interrupts (timer, 712 performance counters), and the NMI watchdog which detects hard 713 lockups. 714 715config X86_UP_IOAPIC 716 bool "IO-APIC support on uniprocessors" 717 depends on X86_UP_APIC 718 ---help--- 719 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 720 SMP-capable replacement for PC-style interrupt controllers. Most 721 SMP systems and many recent uniprocessor systems have one. 722 723 If you have a single-CPU system with an IO-APIC, you can say Y here 724 to use it. If you say Y here even though your machine doesn't have 725 an IO-APIC, then the kernel will still run with no slowdown at all. 726 727config X86_LOCAL_APIC 728 def_bool y 729 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC 730 731config X86_IO_APIC 732 def_bool y 733 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC 734 735config X86_VISWS_APIC 736 def_bool y 737 depends on X86_32 && X86_VISWS 738 739config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 740 bool "Reroute for broken boot IRQs" 741 default n 742 depends on X86_IO_APIC 743 ---help--- 744 This option enables a workaround that fixes a source of 745 spurious interrupts. This is recommended when threaded 746 interrupt handling is used on systems where the generation of 747 superfluous "boot interrupts" cannot be disabled. 748 749 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 750 entry in the chipset's IO-APIC is masked (as, e.g. the RT 751 kernel does during interrupt handling). On chipsets where this 752 boot IRQ generation cannot be disabled, this workaround keeps 753 the original IRQ line masked so that only the equivalent "boot 754 IRQ" is delivered to the CPUs. The workaround also tells the 755 kernel to set up the IRQ handler on the boot IRQ line. In this 756 way only one interrupt is delivered to the kernel. Otherwise 757 the spurious second interrupt may cause the kernel to bring 758 down (vital) interrupt lines. 759 760 Only affects "broken" chipsets. Interrupt sharing may be 761 increased on these systems. 762 763config X86_MCE 764 bool "Machine Check Exception" 765 ---help--- 766 Machine Check Exception support allows the processor to notify the 767 kernel if it detects a problem (e.g. overheating, component failure). 768 The action the kernel takes depends on the severity of the problem, 769 ranging from a warning message on the console, to halting the machine. 770 Your processor must be a Pentium or newer to support this - check the 771 flags in /proc/cpuinfo for mce. Note that some older Pentium systems 772 have a design flaw which leads to false MCE events - hence MCE is 773 disabled on all P5 processors, unless explicitly enabled with "mce" 774 as a boot argument. Similarly, if MCE is built in and creates a 775 problem on some new non-standard machine, you can boot with "nomce" 776 to disable it. MCE support simply ignores non-MCE processors like 777 the 386 and 486, so nearly everyone can say Y here. 778 779config X86_MCE_INTEL 780 def_bool y 781 prompt "Intel MCE features" 782 depends on X86_64 && X86_MCE && X86_LOCAL_APIC 783 ---help--- 784 Additional support for intel specific MCE features such as 785 the thermal monitor. 786 787config X86_MCE_AMD 788 def_bool y 789 prompt "AMD MCE features" 790 depends on X86_64 && X86_MCE && X86_LOCAL_APIC 791 ---help--- 792 Additional support for AMD specific MCE features such as 793 the DRAM Error Threshold. 794 795config X86_MCE_THRESHOLD 796 depends on X86_MCE_AMD || X86_MCE_INTEL 797 bool 798 default y 799 800config X86_MCE_NONFATAL 801 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4" 802 depends on X86_32 && X86_MCE 803 ---help--- 804 Enabling this feature starts a timer that triggers every 5 seconds which 805 will look at the machine check registers to see if anything happened. 806 Non-fatal problems automatically get corrected (but still logged). 807 Disable this if you don't want to see these messages. 808 Seeing the messages this option prints out may be indicative of dying 809 or out-of-spec (ie, overclocked) hardware. 810 This option only does something on certain CPUs. 811 (AMD Athlon/Duron and Intel Pentium 4) 812 813config X86_MCE_P4THERMAL 814 bool "check for P4 thermal throttling interrupt." 815 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) 816 ---help--- 817 Enabling this feature will cause a message to be printed when the P4 818 enters thermal throttling. 819 820config VM86 821 bool "Enable VM86 support" if EMBEDDED 822 default y 823 depends on X86_32 824 ---help--- 825 This option is required by programs like DOSEMU to run 16-bit legacy 826 code on X86 processors. It also may be needed by software like 827 XFree86 to initialize some video cards via BIOS. Disabling this 828 option saves about 6k. 829 830config TOSHIBA 831 tristate "Toshiba Laptop support" 832 depends on X86_32 833 ---help--- 834 This adds a driver to safely access the System Management Mode of 835 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 836 not work on models with a Phoenix BIOS. The System Management Mode 837 is used to set the BIOS and power saving options on Toshiba portables. 838 839 For information on utilities to make use of this driver see the 840 Toshiba Linux utilities web site at: 841 <http://www.buzzard.org.uk/toshiba/>. 842 843 Say Y if you intend to run this kernel on a Toshiba portable. 844 Say N otherwise. 845 846config I8K 847 tristate "Dell laptop support" 848 ---help--- 849 This adds a driver to safely access the System Management Mode 850 of the CPU on the Dell Inspiron 8000. The System Management Mode 851 is used to read cpu temperature and cooling fan status and to 852 control the fans on the I8K portables. 853 854 This driver has been tested only on the Inspiron 8000 but it may 855 also work with other Dell laptops. You can force loading on other 856 models by passing the parameter `force=1' to the module. Use at 857 your own risk. 858 859 For information on utilities to make use of this driver see the 860 I8K Linux utilities web site at: 861 <http://people.debian.org/~dz/i8k/> 862 863 Say Y if you intend to run this kernel on a Dell Inspiron 8000. 864 Say N otherwise. 865 866config X86_REBOOTFIXUPS 867 bool "Enable X86 board specific fixups for reboot" 868 depends on X86_32 869 ---help--- 870 This enables chipset and/or board specific fixups to be done 871 in order to get reboot to work correctly. This is only needed on 872 some combinations of hardware and BIOS. The symptom, for which 873 this config is intended, is when reboot ends with a stalled/hung 874 system. 875 876 Currently, the only fixup is for the Geode machines using 877 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 878 879 Say Y if you want to enable the fixup. Currently, it's safe to 880 enable this option even if you don't need it. 881 Say N otherwise. 882 883config MICROCODE 884 tristate "/dev/cpu/microcode - microcode support" 885 select FW_LOADER 886 ---help--- 887 If you say Y here, you will be able to update the microcode on 888 certain Intel and AMD processors. The Intel support is for the 889 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, 890 Pentium 4, Xeon etc. The AMD support is for family 0x10 and 891 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra. 892 You will obviously need the actual microcode binary data itself 893 which is not shipped with the Linux kernel. 894 895 This option selects the general module only, you need to select 896 at least one vendor specific module as well. 897 898 To compile this driver as a module, choose M here: the 899 module will be called microcode. 900 901config MICROCODE_INTEL 902 bool "Intel microcode patch loading support" 903 depends on MICROCODE 904 default MICROCODE 905 select FW_LOADER 906 ---help--- 907 This options enables microcode patch loading support for Intel 908 processors. 909 910 For latest news and information on obtaining all the required 911 Intel ingredients for this driver, check: 912 <http://www.urbanmyth.org/microcode/>. 913 914config MICROCODE_AMD 915 bool "AMD microcode patch loading support" 916 depends on MICROCODE 917 select FW_LOADER 918 ---help--- 919 If you select this option, microcode patch loading support for AMD 920 processors will be enabled. 921 922config MICROCODE_OLD_INTERFACE 923 def_bool y 924 depends on MICROCODE 925 926config X86_MSR 927 tristate "/dev/cpu/*/msr - Model-specific register support" 928 ---help--- 929 This device gives privileged processes access to the x86 930 Model-Specific Registers (MSRs). It is a character device with 931 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 932 MSR accesses are directed to a specific CPU on multi-processor 933 systems. 934 935config X86_CPUID 936 tristate "/dev/cpu/*/cpuid - CPU information support" 937 ---help--- 938 This device gives processes access to the x86 CPUID instruction to 939 be executed on a specific processor. It is a character device 940 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 941 /dev/cpu/31/cpuid. 942 943config X86_CPU_DEBUG 944 tristate "/sys/kernel/debug/x86/cpu/* - CPU Debug support" 945 ---help--- 946 If you select this option, this will provide various x86 CPUs 947 information through debugfs. 948 949choice 950 prompt "High Memory Support" 951 default HIGHMEM4G if !X86_NUMAQ 952 default HIGHMEM64G if X86_NUMAQ 953 depends on X86_32 954 955config NOHIGHMEM 956 bool "off" 957 depends on !X86_NUMAQ 958 ---help--- 959 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 960 However, the address space of 32-bit x86 processors is only 4 961 Gigabytes large. That means that, if you have a large amount of 962 physical memory, not all of it can be "permanently mapped" by the 963 kernel. The physical memory that's not permanently mapped is called 964 "high memory". 965 966 If you are compiling a kernel which will never run on a machine with 967 more than 1 Gigabyte total physical RAM, answer "off" here (default 968 choice and suitable for most users). This will result in a "3GB/1GB" 969 split: 3GB are mapped so that each process sees a 3GB virtual memory 970 space and the remaining part of the 4GB virtual memory space is used 971 by the kernel to permanently map as much physical memory as 972 possible. 973 974 If the machine has between 1 and 4 Gigabytes physical RAM, then 975 answer "4GB" here. 976 977 If more than 4 Gigabytes is used then answer "64GB" here. This 978 selection turns Intel PAE (Physical Address Extension) mode on. 979 PAE implements 3-level paging on IA32 processors. PAE is fully 980 supported by Linux, PAE mode is implemented on all recent Intel 981 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 982 then the kernel will not boot on CPUs that don't support PAE! 983 984 The actual amount of total physical memory will either be 985 auto detected or can be forced by using a kernel command line option 986 such as "mem=256M". (Try "man bootparam" or see the documentation of 987 your boot loader (lilo or loadlin) about how to pass options to the 988 kernel at boot time.) 989 990 If unsure, say "off". 991 992config HIGHMEM4G 993 bool "4GB" 994 depends on !X86_NUMAQ 995 ---help--- 996 Select this if you have a 32-bit processor and between 1 and 4 997 gigabytes of physical RAM. 998 999config HIGHMEM64G 1000 bool "64GB" 1001 depends on !M386 && !M486 1002 select X86_PAE 1003 ---help--- 1004 Select this if you have a 32-bit processor and more than 4 1005 gigabytes of physical RAM. 1006 1007endchoice 1008 1009choice 1010 depends on EXPERIMENTAL 1011 prompt "Memory split" if EMBEDDED 1012 default VMSPLIT_3G 1013 depends on X86_32 1014 ---help--- 1015 Select the desired split between kernel and user memory. 1016 1017 If the address range available to the kernel is less than the 1018 physical memory installed, the remaining memory will be available 1019 as "high memory". Accessing high memory is a little more costly 1020 than low memory, as it needs to be mapped into the kernel first. 1021 Note that increasing the kernel address space limits the range 1022 available to user programs, making the address space there 1023 tighter. Selecting anything other than the default 3G/1G split 1024 will also likely make your kernel incompatible with binary-only 1025 kernel modules. 1026 1027 If you are not absolutely sure what you are doing, leave this 1028 option alone! 1029 1030 config VMSPLIT_3G 1031 bool "3G/1G user/kernel split" 1032 config VMSPLIT_3G_OPT 1033 depends on !X86_PAE 1034 bool "3G/1G user/kernel split (for full 1G low memory)" 1035 config VMSPLIT_2G 1036 bool "2G/2G user/kernel split" 1037 config VMSPLIT_2G_OPT 1038 depends on !X86_PAE 1039 bool "2G/2G user/kernel split (for full 2G low memory)" 1040 config VMSPLIT_1G 1041 bool "1G/3G user/kernel split" 1042endchoice 1043 1044config PAGE_OFFSET 1045 hex 1046 default 0xB0000000 if VMSPLIT_3G_OPT 1047 default 0x80000000 if VMSPLIT_2G 1048 default 0x78000000 if VMSPLIT_2G_OPT 1049 default 0x40000000 if VMSPLIT_1G 1050 default 0xC0000000 1051 depends on X86_32 1052 1053config HIGHMEM 1054 def_bool y 1055 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1056 1057config X86_PAE 1058 bool "PAE (Physical Address Extension) Support" 1059 depends on X86_32 && !HIGHMEM4G 1060 ---help--- 1061 PAE is required for NX support, and furthermore enables 1062 larger swapspace support for non-overcommit purposes. It 1063 has the cost of more pagetable lookup overhead, and also 1064 consumes more pagetable space per process. 1065 1066config ARCH_PHYS_ADDR_T_64BIT 1067 def_bool X86_64 || X86_PAE 1068 1069config DIRECT_GBPAGES 1070 bool "Enable 1GB pages for kernel pagetables" if EMBEDDED 1071 default y 1072 depends on X86_64 1073 ---help--- 1074 Allow the kernel linear mapping to use 1GB pages on CPUs that 1075 support it. This can improve the kernel's performance a tiny bit by 1076 reducing TLB pressure. If in doubt, say "Y". 1077 1078# Common NUMA Features 1079config NUMA 1080 bool "Numa Memory Allocation and Scheduler Support" 1081 depends on SMP 1082 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL) 1083 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP) 1084 ---help--- 1085 Enable NUMA (Non Uniform Memory Access) support. 1086 1087 The kernel will try to allocate memory used by a CPU on the 1088 local memory controller of the CPU and add some more 1089 NUMA awareness to the kernel. 1090 1091 For 64-bit this is recommended if the system is Intel Core i7 1092 (or later), AMD Opteron, or EM64T NUMA. 1093 1094 For 32-bit this is only needed on (rare) 32-bit-only platforms 1095 that support NUMA topologies, such as NUMAQ / Summit, or if you 1096 boot a 32-bit kernel on a 64-bit NUMA platform. 1097 1098 Otherwise, you should say N. 1099 1100comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI" 1101 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI) 1102 1103config K8_NUMA 1104 def_bool y 1105 prompt "Old style AMD Opteron NUMA detection" 1106 depends on X86_64 && NUMA && PCI 1107 ---help--- 1108 Enable K8 NUMA node topology detection. You should say Y here if 1109 you have a multi processor AMD K8 system. This uses an old 1110 method to read the NUMA configuration directly from the builtin 1111 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA 1112 instead, which also takes priority if both are compiled in. 1113 1114config X86_64_ACPI_NUMA 1115 def_bool y 1116 prompt "ACPI NUMA detection" 1117 depends on X86_64 && NUMA && ACPI && PCI 1118 select ACPI_NUMA 1119 ---help--- 1120 Enable ACPI SRAT based node topology detection. 1121 1122# Some NUMA nodes have memory ranges that span 1123# other nodes. Even though a pfn is valid and 1124# between a node's start and end pfns, it may not 1125# reside on that node. See memmap_init_zone() 1126# for details. 1127config NODES_SPAN_OTHER_NODES 1128 def_bool y 1129 depends on X86_64_ACPI_NUMA 1130 1131config NUMA_EMU 1132 bool "NUMA emulation" 1133 depends on X86_64 && NUMA 1134 ---help--- 1135 Enable NUMA emulation. A flat machine will be split 1136 into virtual nodes when booted with "numa=fake=N", where N is the 1137 number of nodes. This is only useful for debugging. 1138 1139config NODES_SHIFT 1140 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1141 range 1 9 1142 default "9" if MAXSMP 1143 default "6" if X86_64 1144 default "4" if X86_NUMAQ 1145 default "3" 1146 depends on NEED_MULTIPLE_NODES 1147 ---help--- 1148 Specify the maximum number of NUMA Nodes available on the target 1149 system. Increases memory reserved to accommodate various tables. 1150 1151config HAVE_ARCH_BOOTMEM 1152 def_bool y 1153 depends on X86_32 && NUMA 1154 1155config ARCH_HAVE_MEMORY_PRESENT 1156 def_bool y 1157 depends on X86_32 && DISCONTIGMEM 1158 1159config NEED_NODE_MEMMAP_SIZE 1160 def_bool y 1161 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1162 1163config HAVE_ARCH_ALLOC_REMAP 1164 def_bool y 1165 depends on X86_32 && NUMA 1166 1167config ARCH_FLATMEM_ENABLE 1168 def_bool y 1169 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA 1170 1171config ARCH_DISCONTIGMEM_ENABLE 1172 def_bool y 1173 depends on NUMA && X86_32 1174 1175config ARCH_DISCONTIGMEM_DEFAULT 1176 def_bool y 1177 depends on NUMA && X86_32 1178 1179config ARCH_SPARSEMEM_DEFAULT 1180 def_bool y 1181 depends on X86_64 1182 1183config ARCH_SPARSEMEM_ENABLE 1184 def_bool y 1185 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD 1186 select SPARSEMEM_STATIC if X86_32 1187 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1188 1189config ARCH_SELECT_MEMORY_MODEL 1190 def_bool y 1191 depends on ARCH_SPARSEMEM_ENABLE 1192 1193config ARCH_MEMORY_PROBE 1194 def_bool X86_64 1195 depends on MEMORY_HOTPLUG 1196 1197source "mm/Kconfig" 1198 1199config HIGHPTE 1200 bool "Allocate 3rd-level pagetables from highmem" 1201 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G) 1202 ---help--- 1203 The VM uses one page table entry for each page of physical memory. 1204 For systems with a lot of RAM, this can be wasteful of precious 1205 low memory. Setting this option will put user-space page table 1206 entries in high memory. 1207 1208config X86_CHECK_BIOS_CORRUPTION 1209 bool "Check for low memory corruption" 1210 ---help--- 1211 Periodically check for memory corruption in low memory, which 1212 is suspected to be caused by BIOS. Even when enabled in the 1213 configuration, it is disabled at runtime. Enable it by 1214 setting "memory_corruption_check=1" on the kernel command 1215 line. By default it scans the low 64k of memory every 60 1216 seconds; see the memory_corruption_check_size and 1217 memory_corruption_check_period parameters in 1218 Documentation/kernel-parameters.txt to adjust this. 1219 1220 When enabled with the default parameters, this option has 1221 almost no overhead, as it reserves a relatively small amount 1222 of memory and scans it infrequently. It both detects corruption 1223 and prevents it from affecting the running system. 1224 1225 It is, however, intended as a diagnostic tool; if repeatable 1226 BIOS-originated corruption always affects the same memory, 1227 you can use memmap= to prevent the kernel from using that 1228 memory. 1229 1230config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1231 bool "Set the default setting of memory_corruption_check" 1232 depends on X86_CHECK_BIOS_CORRUPTION 1233 default y 1234 ---help--- 1235 Set whether the default state of memory_corruption_check is 1236 on or off. 1237 1238config X86_RESERVE_LOW_64K 1239 bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen" 1240 default y 1241 ---help--- 1242 Reserve the first 64K of physical RAM on BIOSes that are known 1243 to potentially corrupt that memory range. A numbers of BIOSes are 1244 known to utilize this area during suspend/resume, so it must not 1245 be used by the kernel. 1246 1247 Set this to N if you are absolutely sure that you trust the BIOS 1248 to get all its memory reservations and usages right. 1249 1250 If you have doubts about the BIOS (e.g. suspend/resume does not 1251 work or there's kernel crashes after certain hardware hotplug 1252 events) and it's not AMI or Phoenix, then you might want to enable 1253 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical 1254 corruption patterns. 1255 1256 Say Y if unsure. 1257 1258config MATH_EMULATION 1259 bool 1260 prompt "Math emulation" if X86_32 1261 ---help--- 1262 Linux can emulate a math coprocessor (used for floating point 1263 operations) if you don't have one. 486DX and Pentium processors have 1264 a math coprocessor built in, 486SX and 386 do not, unless you added 1265 a 487DX or 387, respectively. (The messages during boot time can 1266 give you some hints here ["man dmesg"].) Everyone needs either a 1267 coprocessor or this emulation. 1268 1269 If you don't have a math coprocessor, you need to say Y here; if you 1270 say Y here even though you have a coprocessor, the coprocessor will 1271 be used nevertheless. (This behavior can be changed with the kernel 1272 command line option "no387", which comes handy if your coprocessor 1273 is broken. Try "man bootparam" or see the documentation of your boot 1274 loader (lilo or loadlin) about how to pass options to the kernel at 1275 boot time.) This means that it is a good idea to say Y here if you 1276 intend to use this kernel on different machines. 1277 1278 More information about the internals of the Linux math coprocessor 1279 emulation can be found in <file:arch/x86/math-emu/README>. 1280 1281 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1282 kernel, it won't hurt. 1283 1284config MTRR 1285 bool "MTRR (Memory Type Range Register) support" 1286 ---help--- 1287 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1288 the Memory Type Range Registers (MTRRs) may be used to control 1289 processor access to memory ranges. This is most useful if you have 1290 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1291 allows bus write transfers to be combined into a larger transfer 1292 before bursting over the PCI/AGP bus. This can increase performance 1293 of image write operations 2.5 times or more. Saying Y here creates a 1294 /proc/mtrr file which may be used to manipulate your processor's 1295 MTRRs. Typically the X server should use this. 1296 1297 This code has a reasonably generic interface so that similar 1298 control registers on other processors can be easily supported 1299 as well: 1300 1301 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1302 Registers (ARRs) which provide a similar functionality to MTRRs. For 1303 these, the ARRs are used to emulate the MTRRs. 1304 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1305 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1306 write-combining. All of these processors are supported by this code 1307 and it makes sense to say Y here if you have one of them. 1308 1309 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1310 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1311 can lead to all sorts of problems, so it's good to say Y here. 1312 1313 You can safely say Y even if your machine doesn't have MTRRs, you'll 1314 just add about 9 KB to your kernel. 1315 1316 See <file:Documentation/x86/mtrr.txt> for more information. 1317 1318config MTRR_SANITIZER 1319 def_bool y 1320 prompt "MTRR cleanup support" 1321 depends on MTRR 1322 ---help--- 1323 Convert MTRR layout from continuous to discrete, so X drivers can 1324 add writeback entries. 1325 1326 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1327 The largest mtrr entry size for a continuous block can be set with 1328 mtrr_chunk_size. 1329 1330 If unsure, say Y. 1331 1332config MTRR_SANITIZER_ENABLE_DEFAULT 1333 int "MTRR cleanup enable value (0-1)" 1334 range 0 1 1335 default "0" 1336 depends on MTRR_SANITIZER 1337 ---help--- 1338 Enable mtrr cleanup default value 1339 1340config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1341 int "MTRR cleanup spare reg num (0-7)" 1342 range 0 7 1343 default "1" 1344 depends on MTRR_SANITIZER 1345 ---help--- 1346 mtrr cleanup spare entries default, it can be changed via 1347 mtrr_spare_reg_nr=N on the kernel command line. 1348 1349config X86_PAT 1350 bool 1351 prompt "x86 PAT support" 1352 depends on MTRR 1353 ---help--- 1354 Use PAT attributes to setup page level cache control. 1355 1356 PATs are the modern equivalents of MTRRs and are much more 1357 flexible than MTRRs. 1358 1359 Say N here if you see bootup problems (boot crash, boot hang, 1360 spontaneous reboots) or a non-working video driver. 1361 1362 If unsure, say Y. 1363 1364config EFI 1365 bool "EFI runtime service support" 1366 depends on ACPI 1367 ---help--- 1368 This enables the kernel to use EFI runtime services that are 1369 available (such as the EFI variable services). 1370 1371 This option is only useful on systems that have EFI firmware. 1372 In addition, you should use the latest ELILO loader available 1373 at <http://elilo.sourceforge.net> in order to take advantage 1374 of EFI runtime services. However, even with this option, the 1375 resultant kernel should continue to boot on existing non-EFI 1376 platforms. 1377 1378config SECCOMP 1379 def_bool y 1380 prompt "Enable seccomp to safely compute untrusted bytecode" 1381 ---help--- 1382 This kernel feature is useful for number crunching applications 1383 that may need to compute untrusted bytecode during their 1384 execution. By using pipes or other transports made available to 1385 the process as file descriptors supporting the read/write 1386 syscalls, it's possible to isolate those applications in 1387 their own address space using seccomp. Once seccomp is 1388 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1389 and the task is only allowed to execute a few safe syscalls 1390 defined by each seccomp mode. 1391 1392 If unsure, say Y. Only embedded should say N here. 1393 1394config CC_STACKPROTECTOR_ALL 1395 bool 1396 1397config CC_STACKPROTECTOR 1398 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)" 1399 select CC_STACKPROTECTOR_ALL 1400 ---help--- 1401 This option turns on the -fstack-protector GCC feature. This 1402 feature puts, at the beginning of functions, a canary value on 1403 the stack just before the return address, and validates 1404 the value just before actually returning. Stack based buffer 1405 overflows (that need to overwrite this return address) now also 1406 overwrite the canary, which gets detected and the attack is then 1407 neutralized via a kernel panic. 1408 1409 This feature requires gcc version 4.2 or above, or a distribution 1410 gcc with the feature backported. Older versions are automatically 1411 detected and for those versions, this configuration option is 1412 ignored. (and a warning is printed during bootup) 1413 1414source kernel/Kconfig.hz 1415 1416config KEXEC 1417 bool "kexec system call" 1418 ---help--- 1419 kexec is a system call that implements the ability to shutdown your 1420 current kernel, and to start another kernel. It is like a reboot 1421 but it is independent of the system firmware. And like a reboot 1422 you can start any kernel with it, not just Linux. 1423 1424 The name comes from the similarity to the exec system call. 1425 1426 It is an ongoing process to be certain the hardware in a machine 1427 is properly shutdown, so do not be surprised if this code does not 1428 initially work for you. It may help to enable device hotplugging 1429 support. As of this writing the exact hardware interface is 1430 strongly in flux, so no good recommendation can be made. 1431 1432config CRASH_DUMP 1433 bool "kernel crash dumps" 1434 depends on X86_64 || (X86_32 && HIGHMEM) 1435 ---help--- 1436 Generate crash dump after being started by kexec. 1437 This should be normally only set in special crash dump kernels 1438 which are loaded in the main kernel with kexec-tools into 1439 a specially reserved region and then later executed after 1440 a crash by kdump/kexec. The crash dump kernel must be compiled 1441 to a memory address not used by the main kernel or BIOS using 1442 PHYSICAL_START, or it must be built as a relocatable image 1443 (CONFIG_RELOCATABLE=y). 1444 For more details see Documentation/kdump/kdump.txt 1445 1446config KEXEC_JUMP 1447 bool "kexec jump (EXPERIMENTAL)" 1448 depends on EXPERIMENTAL 1449 depends on KEXEC && HIBERNATION 1450 ---help--- 1451 Jump between original kernel and kexeced kernel and invoke 1452 code in physical address mode via KEXEC 1453 1454config PHYSICAL_START 1455 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP) 1456 default "0x1000000" if X86_NUMAQ 1457 default "0x200000" if X86_64 1458 default "0x100000" 1459 ---help--- 1460 This gives the physical address where the kernel is loaded. 1461 1462 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1463 bzImage will decompress itself to above physical address and 1464 run from there. Otherwise, bzImage will run from the address where 1465 it has been loaded by the boot loader and will ignore above physical 1466 address. 1467 1468 In normal kdump cases one does not have to set/change this option 1469 as now bzImage can be compiled as a completely relocatable image 1470 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1471 address. This option is mainly useful for the folks who don't want 1472 to use a bzImage for capturing the crash dump and want to use a 1473 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1474 to be specifically compiled to run from a specific memory area 1475 (normally a reserved region) and this option comes handy. 1476 1477 So if you are using bzImage for capturing the crash dump, leave 1478 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y. 1479 Otherwise if you plan to use vmlinux for capturing the crash dump 1480 change this value to start of the reserved region (Typically 16MB 1481 0x1000000). In other words, it can be set based on the "X" value as 1482 specified in the "crashkernel=YM@XM" command line boot parameter 1483 passed to the panic-ed kernel. Typically this parameter is set as 1484 crashkernel=64M@16M. Please take a look at 1485 Documentation/kdump/kdump.txt for more details about crash dumps. 1486 1487 Usage of bzImage for capturing the crash dump is recommended as 1488 one does not have to build two kernels. Same kernel can be used 1489 as production kernel and capture kernel. Above option should have 1490 gone away after relocatable bzImage support is introduced. But it 1491 is present because there are users out there who continue to use 1492 vmlinux for dump capture. This option should go away down the 1493 line. 1494 1495 Don't change this unless you know what you are doing. 1496 1497config RELOCATABLE 1498 bool "Build a relocatable kernel (EXPERIMENTAL)" 1499 depends on EXPERIMENTAL 1500 ---help--- 1501 This builds a kernel image that retains relocation information 1502 so it can be loaded someplace besides the default 1MB. 1503 The relocations tend to make the kernel binary about 10% larger, 1504 but are discarded at runtime. 1505 1506 One use is for the kexec on panic case where the recovery kernel 1507 must live at a different physical address than the primary 1508 kernel. 1509 1510 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1511 it has been loaded at and the compile time physical address 1512 (CONFIG_PHYSICAL_START) is ignored. 1513 1514config PHYSICAL_ALIGN 1515 hex 1516 prompt "Alignment value to which kernel should be aligned" if X86_32 1517 default "0x100000" if X86_32 1518 default "0x200000" if X86_64 1519 range 0x2000 0x400000 1520 ---help--- 1521 This value puts the alignment restrictions on physical address 1522 where kernel is loaded and run from. Kernel is compiled for an 1523 address which meets above alignment restriction. 1524 1525 If bootloader loads the kernel at a non-aligned address and 1526 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1527 address aligned to above value and run from there. 1528 1529 If bootloader loads the kernel at a non-aligned address and 1530 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1531 load address and decompress itself to the address it has been 1532 compiled for and run from there. The address for which kernel is 1533 compiled already meets above alignment restrictions. Hence the 1534 end result is that kernel runs from a physical address meeting 1535 above alignment restrictions. 1536 1537 Don't change this unless you know what you are doing. 1538 1539config HOTPLUG_CPU 1540 bool "Support for hot-pluggable CPUs" 1541 depends on SMP && HOTPLUG 1542 ---help--- 1543 Say Y here to allow turning CPUs off and on. CPUs can be 1544 controlled through /sys/devices/system/cpu. 1545 ( Note: power management support will enable this option 1546 automatically on SMP systems. ) 1547 Say N if you want to disable CPU hotplug. 1548 1549config COMPAT_VDSO 1550 def_bool y 1551 prompt "Compat VDSO support" 1552 depends on X86_32 || IA32_EMULATION 1553 ---help--- 1554 Map the 32-bit VDSO to the predictable old-style address too. 1555 ---help--- 1556 Say N here if you are running a sufficiently recent glibc 1557 version (2.3.3 or later), to remove the high-mapped 1558 VDSO mapping and to exclusively use the randomized VDSO. 1559 1560 If unsure, say Y. 1561 1562config CMDLINE_BOOL 1563 bool "Built-in kernel command line" 1564 default n 1565 ---help--- 1566 Allow for specifying boot arguments to the kernel at 1567 build time. On some systems (e.g. embedded ones), it is 1568 necessary or convenient to provide some or all of the 1569 kernel boot arguments with the kernel itself (that is, 1570 to not rely on the boot loader to provide them.) 1571 1572 To compile command line arguments into the kernel, 1573 set this option to 'Y', then fill in the 1574 the boot arguments in CONFIG_CMDLINE. 1575 1576 Systems with fully functional boot loaders (i.e. non-embedded) 1577 should leave this option set to 'N'. 1578 1579config CMDLINE 1580 string "Built-in kernel command string" 1581 depends on CMDLINE_BOOL 1582 default "" 1583 ---help--- 1584 Enter arguments here that should be compiled into the kernel 1585 image and used at boot time. If the boot loader provides a 1586 command line at boot time, it is appended to this string to 1587 form the full kernel command line, when the system boots. 1588 1589 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 1590 change this behavior. 1591 1592 In most cases, the command line (whether built-in or provided 1593 by the boot loader) should specify the device for the root 1594 file system. 1595 1596config CMDLINE_OVERRIDE 1597 bool "Built-in command line overrides boot loader arguments" 1598 default n 1599 depends on CMDLINE_BOOL 1600 ---help--- 1601 Set this option to 'Y' to have the kernel ignore the boot loader 1602 command line, and use ONLY the built-in command line. 1603 1604 This is used to work around broken boot loaders. This should 1605 be set to 'N' under normal conditions. 1606 1607endmenu 1608 1609config ARCH_ENABLE_MEMORY_HOTPLUG 1610 def_bool y 1611 depends on X86_64 || (X86_32 && HIGHMEM) 1612 1613config ARCH_ENABLE_MEMORY_HOTREMOVE 1614 def_bool y 1615 depends on MEMORY_HOTPLUG 1616 1617config HAVE_ARCH_EARLY_PFN_TO_NID 1618 def_bool X86_64 1619 depends on NUMA 1620 1621menu "Power management and ACPI options" 1622 1623config ARCH_HIBERNATION_HEADER 1624 def_bool y 1625 depends on X86_64 && HIBERNATION 1626 1627source "kernel/power/Kconfig" 1628 1629source "drivers/acpi/Kconfig" 1630 1631config X86_APM_BOOT 1632 bool 1633 default y 1634 depends on APM || APM_MODULE 1635 1636menuconfig APM 1637 tristate "APM (Advanced Power Management) BIOS support" 1638 depends on X86_32 && PM_SLEEP 1639 ---help--- 1640 APM is a BIOS specification for saving power using several different 1641 techniques. This is mostly useful for battery powered laptops with 1642 APM compliant BIOSes. If you say Y here, the system time will be 1643 reset after a RESUME operation, the /proc/apm device will provide 1644 battery status information, and user-space programs will receive 1645 notification of APM "events" (e.g. battery status change). 1646 1647 If you select "Y" here, you can disable actual use of the APM 1648 BIOS by passing the "apm=off" option to the kernel at boot time. 1649 1650 Note that the APM support is almost completely disabled for 1651 machines with more than one CPU. 1652 1653 In order to use APM, you will need supporting software. For location 1654 and more information, read <file:Documentation/power/pm.txt> and the 1655 Battery Powered Linux mini-HOWTO, available from 1656 <http://www.tldp.org/docs.html#howto>. 1657 1658 This driver does not spin down disk drives (see the hdparm(8) 1659 manpage ("man 8 hdparm") for that), and it doesn't turn off 1660 VESA-compliant "green" monitors. 1661 1662 This driver does not support the TI 4000M TravelMate and the ACER 1663 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1664 desktop machines also don't have compliant BIOSes, and this driver 1665 may cause those machines to panic during the boot phase. 1666 1667 Generally, if you don't have a battery in your machine, there isn't 1668 much point in using this driver and you should say N. If you get 1669 random kernel OOPSes or reboots that don't seem to be related to 1670 anything, try disabling/enabling this option (or disabling/enabling 1671 APM in your BIOS). 1672 1673 Some other things you should try when experiencing seemingly random, 1674 "weird" problems: 1675 1676 1) make sure that you have enough swap space and that it is 1677 enabled. 1678 2) pass the "no-hlt" option to the kernel 1679 3) switch on floating point emulation in the kernel and pass 1680 the "no387" option to the kernel 1681 4) pass the "floppy=nodma" option to the kernel 1682 5) pass the "mem=4M" option to the kernel (thereby disabling 1683 all but the first 4 MB of RAM) 1684 6) make sure that the CPU is not over clocked. 1685 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1686 8) disable the cache from your BIOS settings 1687 9) install a fan for the video card or exchange video RAM 1688 10) install a better fan for the CPU 1689 11) exchange RAM chips 1690 12) exchange the motherboard. 1691 1692 To compile this driver as a module, choose M here: the 1693 module will be called apm. 1694 1695if APM 1696 1697config APM_IGNORE_USER_SUSPEND 1698 bool "Ignore USER SUSPEND" 1699 ---help--- 1700 This option will ignore USER SUSPEND requests. On machines with a 1701 compliant APM BIOS, you want to say N. However, on the NEC Versa M 1702 series notebooks, it is necessary to say Y because of a BIOS bug. 1703 1704config APM_DO_ENABLE 1705 bool "Enable PM at boot time" 1706 ---help--- 1707 Enable APM features at boot time. From page 36 of the APM BIOS 1708 specification: "When disabled, the APM BIOS does not automatically 1709 power manage devices, enter the Standby State, enter the Suspend 1710 State, or take power saving steps in response to CPU Idle calls." 1711 This driver will make CPU Idle calls when Linux is idle (unless this 1712 feature is turned off -- see "Do CPU IDLE calls", below). This 1713 should always save battery power, but more complicated APM features 1714 will be dependent on your BIOS implementation. You may need to turn 1715 this option off if your computer hangs at boot time when using APM 1716 support, or if it beeps continuously instead of suspending. Turn 1717 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1718 T400CDT. This is off by default since most machines do fine without 1719 this feature. 1720 1721config APM_CPU_IDLE 1722 bool "Make CPU Idle calls when idle" 1723 ---help--- 1724 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 1725 On some machines, this can activate improved power savings, such as 1726 a slowed CPU clock rate, when the machine is idle. These idle calls 1727 are made after the idle loop has run for some length of time (e.g., 1728 333 mS). On some machines, this will cause a hang at boot time or 1729 whenever the CPU becomes idle. (On machines with more than one CPU, 1730 this option does nothing.) 1731 1732config APM_DISPLAY_BLANK 1733 bool "Enable console blanking using APM" 1734 ---help--- 1735 Enable console blanking using the APM. Some laptops can use this to 1736 turn off the LCD backlight when the screen blanker of the Linux 1737 virtual console blanks the screen. Note that this is only used by 1738 the virtual console screen blanker, and won't turn off the backlight 1739 when using the X Window system. This also doesn't have anything to 1740 do with your VESA-compliant power-saving monitor. Further, this 1741 option doesn't work for all laptops -- it might not turn off your 1742 backlight at all, or it might print a lot of errors to the console, 1743 especially if you are using gpm. 1744 1745config APM_ALLOW_INTS 1746 bool "Allow interrupts during APM BIOS calls" 1747 ---help--- 1748 Normally we disable external interrupts while we are making calls to 1749 the APM BIOS as a measure to lessen the effects of a badly behaving 1750 BIOS implementation. The BIOS should reenable interrupts if it 1751 needs to. Unfortunately, some BIOSes do not -- especially those in 1752 many of the newer IBM Thinkpads. If you experience hangs when you 1753 suspend, try setting this to Y. Otherwise, say N. 1754 1755endif # APM 1756 1757source "arch/x86/kernel/cpu/cpufreq/Kconfig" 1758 1759source "drivers/cpuidle/Kconfig" 1760 1761source "drivers/idle/Kconfig" 1762 1763endmenu 1764 1765 1766menu "Bus options (PCI etc.)" 1767 1768config PCI 1769 bool "PCI support" 1770 default y 1771 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC) 1772 ---help--- 1773 Find out whether you have a PCI motherboard. PCI is the name of a 1774 bus system, i.e. the way the CPU talks to the other stuff inside 1775 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 1776 VESA. If you have PCI, say Y, otherwise N. 1777 1778choice 1779 prompt "PCI access mode" 1780 depends on X86_32 && PCI 1781 default PCI_GOANY 1782 ---help--- 1783 On PCI systems, the BIOS can be used to detect the PCI devices and 1784 determine their configuration. However, some old PCI motherboards 1785 have BIOS bugs and may crash if this is done. Also, some embedded 1786 PCI-based systems don't have any BIOS at all. Linux can also try to 1787 detect the PCI hardware directly without using the BIOS. 1788 1789 With this option, you can specify how Linux should detect the 1790 PCI devices. If you choose "BIOS", the BIOS will be used, 1791 if you choose "Direct", the BIOS won't be used, and if you 1792 choose "MMConfig", then PCI Express MMCONFIG will be used. 1793 If you choose "Any", the kernel will try MMCONFIG, then the 1794 direct access method and falls back to the BIOS if that doesn't 1795 work. If unsure, go with the default, which is "Any". 1796 1797config PCI_GOBIOS 1798 bool "BIOS" 1799 1800config PCI_GOMMCONFIG 1801 bool "MMConfig" 1802 1803config PCI_GODIRECT 1804 bool "Direct" 1805 1806config PCI_GOOLPC 1807 bool "OLPC" 1808 depends on OLPC 1809 1810config PCI_GOANY 1811 bool "Any" 1812 1813endchoice 1814 1815config PCI_BIOS 1816 def_bool y 1817 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 1818 1819# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 1820config PCI_DIRECT 1821 def_bool y 1822 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC)) 1823 1824config PCI_MMCONFIG 1825 def_bool y 1826 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY) 1827 1828config PCI_OLPC 1829 def_bool y 1830 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 1831 1832config PCI_DOMAINS 1833 def_bool y 1834 depends on PCI 1835 1836config PCI_MMCONFIG 1837 bool "Support mmconfig PCI config space access" 1838 depends on X86_64 && PCI && ACPI 1839 1840config DMAR 1841 bool "Support for DMA Remapping Devices (EXPERIMENTAL)" 1842 depends on PCI_MSI && ACPI && EXPERIMENTAL 1843 help 1844 DMA remapping (DMAR) devices support enables independent address 1845 translations for Direct Memory Access (DMA) from devices. 1846 These DMA remapping devices are reported via ACPI tables 1847 and include PCI device scope covered by these DMA 1848 remapping devices. 1849 1850config DMAR_DEFAULT_ON 1851 def_bool y 1852 prompt "Enable DMA Remapping Devices by default" 1853 depends on DMAR 1854 help 1855 Selecting this option will enable a DMAR device at boot time if 1856 one is found. If this option is not selected, DMAR support can 1857 be enabled by passing intel_iommu=on to the kernel. It is 1858 recommended you say N here while the DMAR code remains 1859 experimental. 1860 1861config DMAR_GFX_WA 1862 def_bool y 1863 prompt "Support for Graphics workaround" 1864 depends on DMAR 1865 ---help--- 1866 Current Graphics drivers tend to use physical address 1867 for DMA and avoid using DMA APIs. Setting this config 1868 option permits the IOMMU driver to set a unity map for 1869 all the OS-visible memory. Hence the driver can continue 1870 to use physical addresses for DMA. 1871 1872config DMAR_FLOPPY_WA 1873 def_bool y 1874 depends on DMAR 1875 ---help--- 1876 Floppy disk drivers are know to bypass DMA API calls 1877 thereby failing to work when IOMMU is enabled. This 1878 workaround will setup a 1:1 mapping for the first 1879 16M to make floppy (an ISA device) work. 1880 1881config INTR_REMAP 1882 bool "Support for Interrupt Remapping (EXPERIMENTAL)" 1883 depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL 1884 ---help--- 1885 Supports Interrupt remapping for IO-APIC and MSI devices. 1886 To use x2apic mode in the CPU's which support x2APIC enhancements or 1887 to support platforms with CPU's having > 8 bit APIC ID, say Y. 1888 1889source "drivers/pci/pcie/Kconfig" 1890 1891source "drivers/pci/Kconfig" 1892 1893# x86_64 have no ISA slots, but do have ISA-style DMA. 1894config ISA_DMA_API 1895 def_bool y 1896 1897if X86_32 1898 1899config ISA 1900 bool "ISA support" 1901 ---help--- 1902 Find out whether you have ISA slots on your motherboard. ISA is the 1903 name of a bus system, i.e. the way the CPU talks to the other stuff 1904 inside your box. Other bus systems are PCI, EISA, MicroChannel 1905 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 1906 newer boards don't support it. If you have ISA, say Y, otherwise N. 1907 1908config EISA 1909 bool "EISA support" 1910 depends on ISA 1911 ---help--- 1912 The Extended Industry Standard Architecture (EISA) bus was 1913 developed as an open alternative to the IBM MicroChannel bus. 1914 1915 The EISA bus provided some of the features of the IBM MicroChannel 1916 bus while maintaining backward compatibility with cards made for 1917 the older ISA bus. The EISA bus saw limited use between 1988 and 1918 1995 when it was made obsolete by the PCI bus. 1919 1920 Say Y here if you are building a kernel for an EISA-based machine. 1921 1922 Otherwise, say N. 1923 1924source "drivers/eisa/Kconfig" 1925 1926config MCA 1927 bool "MCA support" 1928 ---help--- 1929 MicroChannel Architecture is found in some IBM PS/2 machines and 1930 laptops. It is a bus system similar to PCI or ISA. See 1931 <file:Documentation/mca.txt> (and especially the web page given 1932 there) before attempting to build an MCA bus kernel. 1933 1934source "drivers/mca/Kconfig" 1935 1936config SCx200 1937 tristate "NatSemi SCx200 support" 1938 ---help--- 1939 This provides basic support for National Semiconductor's 1940 (now AMD's) Geode processors. The driver probes for the 1941 PCI-IDs of several on-chip devices, so its a good dependency 1942 for other scx200_* drivers. 1943 1944 If compiled as a module, the driver is named scx200. 1945 1946config SCx200HR_TIMER 1947 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 1948 depends on SCx200 && GENERIC_TIME 1949 default y 1950 ---help--- 1951 This driver provides a clocksource built upon the on-chip 1952 27MHz high-resolution timer. Its also a workaround for 1953 NSC Geode SC-1100's buggy TSC, which loses time when the 1954 processor goes idle (as is done by the scheduler). The 1955 other workaround is idle=poll boot option. 1956 1957config GEODE_MFGPT_TIMER 1958 def_bool y 1959 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events" 1960 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS 1961 ---help--- 1962 This driver provides a clock event source based on the MFGPT 1963 timer(s) in the CS5535 and CS5536 companion chip for the geode. 1964 MFGPTs have a better resolution and max interval than the 1965 generic PIT, and are suitable for use as high-res timers. 1966 1967config OLPC 1968 bool "One Laptop Per Child support" 1969 default n 1970 ---help--- 1971 Add support for detecting the unique features of the OLPC 1972 XO hardware. 1973 1974endif # X86_32 1975 1976config K8_NB 1977 def_bool y 1978 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA))) 1979 1980source "drivers/pcmcia/Kconfig" 1981 1982source "drivers/pci/hotplug/Kconfig" 1983 1984endmenu 1985 1986 1987menu "Executable file formats / Emulations" 1988 1989source "fs/Kconfig.binfmt" 1990 1991config IA32_EMULATION 1992 bool "IA32 Emulation" 1993 depends on X86_64 1994 select COMPAT_BINFMT_ELF 1995 ---help--- 1996 Include code to run 32-bit programs under a 64-bit kernel. You should 1997 likely turn this on, unless you're 100% sure that you don't have any 1998 32-bit programs left. 1999 2000config IA32_AOUT 2001 tristate "IA32 a.out support" 2002 depends on IA32_EMULATION 2003 ---help--- 2004 Support old a.out binaries in the 32bit emulation. 2005 2006config COMPAT 2007 def_bool y 2008 depends on IA32_EMULATION 2009 2010config COMPAT_FOR_U64_ALIGNMENT 2011 def_bool COMPAT 2012 depends on X86_64 2013 2014config SYSVIPC_COMPAT 2015 def_bool y 2016 depends on COMPAT && SYSVIPC 2017 2018endmenu 2019 2020 2021config HAVE_ATOMIC_IOMAP 2022 def_bool y 2023 depends on X86_32 2024 2025source "net/Kconfig" 2026 2027source "drivers/Kconfig" 2028 2029source "drivers/firmware/Kconfig" 2030 2031source "fs/Kconfig" 2032 2033source "arch/x86/Kconfig.debug" 2034 2035source "security/Kconfig" 2036 2037source "crypto/Kconfig" 2038 2039source "arch/x86/kvm/Kconfig" 2040 2041source "lib/Kconfig" 2042