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_PERF_EVENTS 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_KERNEL_LZO 53 select HAVE_HW_BREAKPOINT 54 select PERF_EVENTS 55 select ANON_INODES 56 select HAVE_ARCH_KMEMCHECK 57 select HAVE_USER_RETURN_NOTIFIER 58 59config OUTPUT_FORMAT 60 string 61 default "elf32-i386" if X86_32 62 default "elf64-x86-64" if X86_64 63 64config ARCH_DEFCONFIG 65 string 66 default "arch/x86/configs/i386_defconfig" if X86_32 67 default "arch/x86/configs/x86_64_defconfig" if X86_64 68 69config GENERIC_TIME 70 def_bool y 71 72config GENERIC_CMOS_UPDATE 73 def_bool y 74 75config CLOCKSOURCE_WATCHDOG 76 def_bool y 77 78config GENERIC_CLOCKEVENTS 79 def_bool y 80 81config GENERIC_CLOCKEVENTS_BROADCAST 82 def_bool y 83 depends on X86_64 || (X86_32 && X86_LOCAL_APIC) 84 85config LOCKDEP_SUPPORT 86 def_bool y 87 88config STACKTRACE_SUPPORT 89 def_bool y 90 91config HAVE_LATENCYTOP_SUPPORT 92 def_bool y 93 94config MMU 95 def_bool y 96 97config ZONE_DMA 98 def_bool y 99 100config SBUS 101 bool 102 103config GENERIC_ISA_DMA 104 def_bool y 105 106config GENERIC_IOMAP 107 def_bool y 108 109config GENERIC_BUG 110 def_bool y 111 depends on BUG 112 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 113 114config GENERIC_BUG_RELATIVE_POINTERS 115 bool 116 117config GENERIC_HWEIGHT 118 def_bool y 119 120config GENERIC_GPIO 121 bool 122 123config ARCH_MAY_HAVE_PC_FDC 124 def_bool y 125 126config RWSEM_GENERIC_SPINLOCK 127 def_bool !X86_XADD 128 129config RWSEM_XCHGADD_ALGORITHM 130 def_bool X86_XADD 131 132config ARCH_HAS_CPU_IDLE_WAIT 133 def_bool y 134 135config GENERIC_CALIBRATE_DELAY 136 def_bool y 137 138config GENERIC_TIME_VSYSCALL 139 bool 140 default X86_64 141 142config ARCH_HAS_CPU_RELAX 143 def_bool y 144 145config ARCH_HAS_DEFAULT_IDLE 146 def_bool y 147 148config ARCH_HAS_CACHE_LINE_SIZE 149 def_bool y 150 151config HAVE_SETUP_PER_CPU_AREA 152 def_bool y 153 154config NEED_PER_CPU_EMBED_FIRST_CHUNK 155 def_bool y 156 157config NEED_PER_CPU_PAGE_FIRST_CHUNK 158 def_bool y 159 160config HAVE_CPUMASK_OF_CPU_MAP 161 def_bool X86_64_SMP 162 163config ARCH_HIBERNATION_POSSIBLE 164 def_bool y 165 166config ARCH_SUSPEND_POSSIBLE 167 def_bool y 168 169config ZONE_DMA32 170 bool 171 default X86_64 172 173config ARCH_POPULATES_NODE_MAP 174 def_bool y 175 176config AUDIT_ARCH 177 bool 178 default X86_64 179 180config ARCH_SUPPORTS_OPTIMIZED_INLINING 181 def_bool y 182 183config ARCH_SUPPORTS_DEBUG_PAGEALLOC 184 def_bool y 185 186config HAVE_INTEL_TXT 187 def_bool y 188 depends on EXPERIMENTAL && DMAR && ACPI 189 190# Use the generic interrupt handling code in kernel/irq/: 191config GENERIC_HARDIRQS 192 bool 193 default y 194 195config GENERIC_HARDIRQS_NO__DO_IRQ 196 def_bool y 197 198config GENERIC_IRQ_PROBE 199 bool 200 default y 201 202config GENERIC_PENDING_IRQ 203 bool 204 depends on GENERIC_HARDIRQS && SMP 205 default y 206 207config USE_GENERIC_SMP_HELPERS 208 def_bool y 209 depends on SMP 210 211config X86_32_SMP 212 def_bool y 213 depends on X86_32 && SMP 214 215config X86_64_SMP 216 def_bool y 217 depends on X86_64 && SMP 218 219config X86_HT 220 bool 221 depends on SMP 222 default y 223 224config X86_TRAMPOLINE 225 bool 226 depends on SMP || (64BIT && ACPI_SLEEP) 227 default y 228 229config X86_32_LAZY_GS 230 def_bool y 231 depends on X86_32 && !CC_STACKPROTECTOR 232 233config KTIME_SCALAR 234 def_bool X86_32 235source "init/Kconfig" 236source "kernel/Kconfig.freezer" 237 238menu "Processor type and features" 239 240source "kernel/time/Kconfig" 241 242config SMP 243 bool "Symmetric multi-processing support" 244 ---help--- 245 This enables support for systems with more than one CPU. If you have 246 a system with only one CPU, like most personal computers, say N. If 247 you have a system with more than one CPU, say Y. 248 249 If you say N here, the kernel will run on single and multiprocessor 250 machines, but will use only one CPU of a multiprocessor machine. If 251 you say Y here, the kernel will run on many, but not all, 252 singleprocessor machines. On a singleprocessor machine, the kernel 253 will run faster if you say N here. 254 255 Note that if you say Y here and choose architecture "586" or 256 "Pentium" under "Processor family", the kernel will not work on 486 257 architectures. Similarly, multiprocessor kernels for the "PPro" 258 architecture may not work on all Pentium based boards. 259 260 People using multiprocessor machines who say Y here should also say 261 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 262 Management" code will be disabled if you say Y here. 263 264 See also <file:Documentation/i386/IO-APIC.txt>, 265 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 266 <http://www.tldp.org/docs.html#howto>. 267 268 If you don't know what to do here, say N. 269 270config X86_X2APIC 271 bool "Support x2apic" 272 depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP 273 ---help--- 274 This enables x2apic support on CPUs that have this feature. 275 276 This allows 32-bit apic IDs (so it can support very large systems), 277 and accesses the local apic via MSRs not via mmio. 278 279 If you don't know what to do here, say N. 280 281config SPARSE_IRQ 282 bool "Support sparse irq numbering" 283 depends on PCI_MSI || HT_IRQ 284 ---help--- 285 This enables support for sparse irqs. This is useful for distro 286 kernels that want to define a high CONFIG_NR_CPUS value but still 287 want to have low kernel memory footprint on smaller machines. 288 289 ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread 290 out the irq_desc[] array in a more NUMA-friendly way. ) 291 292 If you don't know what to do here, say N. 293 294config NUMA_IRQ_DESC 295 def_bool y 296 depends on SPARSE_IRQ && NUMA 297 298config X86_MPPARSE 299 bool "Enable MPS table" if ACPI 300 default y 301 depends on X86_LOCAL_APIC 302 ---help--- 303 For old smp systems that do not have proper acpi support. Newer systems 304 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 305 306config X86_BIGSMP 307 bool "Support for big SMP systems with more than 8 CPUs" 308 depends on X86_32 && SMP 309 ---help--- 310 This option is needed for the systems that have more than 8 CPUs 311 312if X86_32 313config X86_EXTENDED_PLATFORM 314 bool "Support for extended (non-PC) x86 platforms" 315 default y 316 ---help--- 317 If you disable this option then the kernel will only support 318 standard PC platforms. (which covers the vast majority of 319 systems out there.) 320 321 If you enable this option then you'll be able to select support 322 for the following (non-PC) 32 bit x86 platforms: 323 AMD Elan 324 NUMAQ (IBM/Sequent) 325 RDC R-321x SoC 326 SGI 320/540 (Visual Workstation) 327 Summit/EXA (IBM x440) 328 Unisys ES7000 IA32 series 329 Moorestown MID devices 330 331 If you have one of these systems, or if you want to build a 332 generic distribution kernel, say Y here - otherwise say N. 333endif 334 335if X86_64 336config X86_EXTENDED_PLATFORM 337 bool "Support for extended (non-PC) x86 platforms" 338 default y 339 ---help--- 340 If you disable this option then the kernel will only support 341 standard PC platforms. (which covers the vast majority of 342 systems out there.) 343 344 If you enable this option then you'll be able to select support 345 for the following (non-PC) 64 bit x86 platforms: 346 ScaleMP vSMP 347 SGI Ultraviolet 348 349 If you have one of these systems, or if you want to build a 350 generic distribution kernel, say Y here - otherwise say N. 351endif 352# This is an alphabetically sorted list of 64 bit extended platforms 353# Please maintain the alphabetic order if and when there are additions 354 355config X86_VSMP 356 bool "ScaleMP vSMP" 357 select PARAVIRT 358 depends on X86_64 && PCI 359 depends on X86_EXTENDED_PLATFORM 360 ---help--- 361 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 362 supposed to run on these EM64T-based machines. Only choose this option 363 if you have one of these machines. 364 365config X86_UV 366 bool "SGI Ultraviolet" 367 depends on X86_64 368 depends on X86_EXTENDED_PLATFORM 369 depends on NUMA 370 depends on X86_X2APIC 371 ---help--- 372 This option is needed in order to support SGI Ultraviolet systems. 373 If you don't have one of these, you should say N here. 374 375# Following is an alphabetically sorted list of 32 bit extended platforms 376# Please maintain the alphabetic order if and when there are additions 377 378config X86_ELAN 379 bool "AMD Elan" 380 depends on X86_32 381 depends on X86_EXTENDED_PLATFORM 382 ---help--- 383 Select this for an AMD Elan processor. 384 385 Do not use this option for K6/Athlon/Opteron processors! 386 387 If unsure, choose "PC-compatible" instead. 388 389config X86_MRST 390 bool "Moorestown MID platform" 391 depends on X86_32 392 depends on X86_EXTENDED_PLATFORM 393 ---help--- 394 Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin 395 Internet Device(MID) platform. Moorestown consists of two chips: 396 Lincroft (CPU core, graphics, and memory controller) and Langwell IOH. 397 Unlike standard x86 PCs, Moorestown does not have many legacy devices 398 nor standard legacy replacement devices/features. e.g. Moorestown does 399 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports. 400 401config X86_RDC321X 402 bool "RDC R-321x SoC" 403 depends on X86_32 404 depends on X86_EXTENDED_PLATFORM 405 select M486 406 select X86_REBOOTFIXUPS 407 ---help--- 408 This option is needed for RDC R-321x system-on-chip, also known 409 as R-8610-(G). 410 If you don't have one of these chips, you should say N here. 411 412config X86_32_NON_STANDARD 413 bool "Support non-standard 32-bit SMP architectures" 414 depends on X86_32 && SMP 415 depends on X86_EXTENDED_PLATFORM 416 ---help--- 417 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default 418 subarchitectures. It is intended for a generic binary kernel. 419 if you select them all, kernel will probe it one by one. and will 420 fallback to default. 421 422# Alphabetically sorted list of Non standard 32 bit platforms 423 424config X86_NUMAQ 425 bool "NUMAQ (IBM/Sequent)" 426 depends on X86_32_NON_STANDARD 427 select NUMA 428 select X86_MPPARSE 429 ---help--- 430 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent) 431 NUMA multiquad box. This changes the way that processors are 432 bootstrapped, and uses Clustered Logical APIC addressing mode instead 433 of Flat Logical. You will need a new lynxer.elf file to flash your 434 firmware with - send email to <Martin.Bligh@us.ibm.com>. 435 436config X86_SUPPORTS_MEMORY_FAILURE 437 bool 438 # MCE code calls memory_failure(): 439 depends on X86_MCE 440 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 441 depends on !X86_NUMAQ 442 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 443 depends on X86_64 || !SPARSEMEM 444 select ARCH_SUPPORTS_MEMORY_FAILURE 445 default y 446 447config X86_VISWS 448 bool "SGI 320/540 (Visual Workstation)" 449 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT 450 depends on X86_32_NON_STANDARD 451 ---help--- 452 The SGI Visual Workstation series is an IA32-based workstation 453 based on SGI systems chips with some legacy PC hardware attached. 454 455 Say Y here to create a kernel to run on the SGI 320 or 540. 456 457 A kernel compiled for the Visual Workstation will run on general 458 PCs as well. See <file:Documentation/sgi-visws.txt> for details. 459 460config X86_SUMMIT 461 bool "Summit/EXA (IBM x440)" 462 depends on X86_32_NON_STANDARD 463 ---help--- 464 This option is needed for IBM systems that use the Summit/EXA chipset. 465 In particular, it is needed for the x440. 466 467config X86_ES7000 468 bool "Unisys ES7000 IA32 series" 469 depends on X86_32_NON_STANDARD && X86_BIGSMP 470 ---help--- 471 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is 472 supposed to run on an IA32-based Unisys ES7000 system. 473 474config SCHED_OMIT_FRAME_POINTER 475 def_bool y 476 prompt "Single-depth WCHAN output" 477 depends on X86 478 ---help--- 479 Calculate simpler /proc/<PID>/wchan values. If this option 480 is disabled then wchan values will recurse back to the 481 caller function. This provides more accurate wchan values, 482 at the expense of slightly more scheduling overhead. 483 484 If in doubt, say "Y". 485 486menuconfig PARAVIRT_GUEST 487 bool "Paravirtualized guest support" 488 ---help--- 489 Say Y here to get to see options related to running Linux under 490 various hypervisors. This option alone does not add any kernel code. 491 492 If you say N, all options in this submenu will be skipped and disabled. 493 494if PARAVIRT_GUEST 495 496source "arch/x86/xen/Kconfig" 497 498config VMI 499 bool "VMI Guest support (DEPRECATED)" 500 select PARAVIRT 501 depends on X86_32 502 ---help--- 503 VMI provides a paravirtualized interface to the VMware ESX server 504 (it could be used by other hypervisors in theory too, but is not 505 at the moment), by linking the kernel to a GPL-ed ROM module 506 provided by the hypervisor. 507 508 As of September 2009, VMware has started a phased retirement 509 of this feature from VMware's products. Please see 510 feature-removal-schedule.txt for details. If you are 511 planning to enable this option, please note that you cannot 512 live migrate a VMI enabled VM to a future VMware product, 513 which doesn't support VMI. So if you expect your kernel to 514 seamlessly migrate to newer VMware products, keep this 515 disabled. 516 517config KVM_CLOCK 518 bool "KVM paravirtualized clock" 519 select PARAVIRT 520 select PARAVIRT_CLOCK 521 ---help--- 522 Turning on this option will allow you to run a paravirtualized clock 523 when running over the KVM hypervisor. Instead of relying on a PIT 524 (or probably other) emulation by the underlying device model, the host 525 provides the guest with timing infrastructure such as time of day, and 526 system time 527 528config KVM_GUEST 529 bool "KVM Guest support" 530 select PARAVIRT 531 ---help--- 532 This option enables various optimizations for running under the KVM 533 hypervisor. 534 535source "arch/x86/lguest/Kconfig" 536 537config PARAVIRT 538 bool "Enable paravirtualization code" 539 ---help--- 540 This changes the kernel so it can modify itself when it is run 541 under a hypervisor, potentially improving performance significantly 542 over full virtualization. However, when run without a hypervisor 543 the kernel is theoretically slower and slightly larger. 544 545config PARAVIRT_SPINLOCKS 546 bool "Paravirtualization layer for spinlocks" 547 depends on PARAVIRT && SMP && EXPERIMENTAL 548 ---help--- 549 Paravirtualized spinlocks allow a pvops backend to replace the 550 spinlock implementation with something virtualization-friendly 551 (for example, block the virtual CPU rather than spinning). 552 553 Unfortunately the downside is an up to 5% performance hit on 554 native kernels, with various workloads. 555 556 If you are unsure how to answer this question, answer N. 557 558config PARAVIRT_CLOCK 559 bool 560 default n 561 562endif 563 564config PARAVIRT_DEBUG 565 bool "paravirt-ops debugging" 566 depends on PARAVIRT && DEBUG_KERNEL 567 ---help--- 568 Enable to debug paravirt_ops internals. Specifically, BUG if 569 a paravirt_op is missing when it is called. 570 571config MEMTEST 572 bool "Memtest" 573 ---help--- 574 This option adds a kernel parameter 'memtest', which allows memtest 575 to be set. 576 memtest=0, mean disabled; -- default 577 memtest=1, mean do 1 test pattern; 578 ... 579 memtest=4, mean do 4 test patterns. 580 If you are unsure how to answer this question, answer N. 581 582config X86_SUMMIT_NUMA 583 def_bool y 584 depends on X86_32 && NUMA && X86_32_NON_STANDARD 585 586config X86_CYCLONE_TIMER 587 def_bool y 588 depends on X86_32_NON_STANDARD 589 590source "arch/x86/Kconfig.cpu" 591 592config HPET_TIMER 593 def_bool X86_64 594 prompt "HPET Timer Support" if X86_32 595 ---help--- 596 Use the IA-PC HPET (High Precision Event Timer) to manage 597 time in preference to the PIT and RTC, if a HPET is 598 present. 599 HPET is the next generation timer replacing legacy 8254s. 600 The HPET provides a stable time base on SMP 601 systems, unlike the TSC, but it is more expensive to access, 602 as it is off-chip. You can find the HPET spec at 603 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>. 604 605 You can safely choose Y here. However, HPET will only be 606 activated if the platform and the BIOS support this feature. 607 Otherwise the 8254 will be used for timing services. 608 609 Choose N to continue using the legacy 8254 timer. 610 611config HPET_EMULATE_RTC 612 def_bool y 613 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 614 615# Mark as embedded because too many people got it wrong. 616# The code disables itself when not needed. 617config DMI 618 default y 619 bool "Enable DMI scanning" if EMBEDDED 620 ---help--- 621 Enabled scanning of DMI to identify machine quirks. Say Y 622 here unless you have verified that your setup is not 623 affected by entries in the DMI blacklist. Required by PNP 624 BIOS code. 625 626config GART_IOMMU 627 bool "GART IOMMU support" if EMBEDDED 628 default y 629 select SWIOTLB 630 depends on X86_64 && PCI 631 ---help--- 632 Support for full DMA access of devices with 32bit memory access only 633 on systems with more than 3GB. This is usually needed for USB, 634 sound, many IDE/SATA chipsets and some other devices. 635 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART 636 based hardware IOMMU and a software bounce buffer based IOMMU used 637 on Intel systems and as fallback. 638 The code is only active when needed (enough memory and limited 639 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified 640 too. 641 642config CALGARY_IOMMU 643 bool "IBM Calgary IOMMU support" 644 select SWIOTLB 645 depends on X86_64 && PCI && EXPERIMENTAL 646 ---help--- 647 Support for hardware IOMMUs in IBM's xSeries x366 and x460 648 systems. Needed to run systems with more than 3GB of memory 649 properly with 32-bit PCI devices that do not support DAC 650 (Double Address Cycle). Calgary also supports bus level 651 isolation, where all DMAs pass through the IOMMU. This 652 prevents them from going anywhere except their intended 653 destination. This catches hard-to-find kernel bugs and 654 mis-behaving drivers and devices that do not use the DMA-API 655 properly to set up their DMA buffers. The IOMMU can be 656 turned off at boot time with the iommu=off parameter. 657 Normally the kernel will make the right choice by itself. 658 If unsure, say Y. 659 660config CALGARY_IOMMU_ENABLED_BY_DEFAULT 661 def_bool y 662 prompt "Should Calgary be enabled by default?" 663 depends on CALGARY_IOMMU 664 ---help--- 665 Should Calgary be enabled by default? if you choose 'y', Calgary 666 will be used (if it exists). If you choose 'n', Calgary will not be 667 used even if it exists. If you choose 'n' and would like to use 668 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 669 If unsure, say Y. 670 671config AMD_IOMMU 672 bool "AMD IOMMU support" 673 select SWIOTLB 674 select PCI_MSI 675 depends on X86_64 && PCI && ACPI 676 ---help--- 677 With this option you can enable support for AMD IOMMU hardware in 678 your system. An IOMMU is a hardware component which provides 679 remapping of DMA memory accesses from devices. With an AMD IOMMU you 680 can isolate the the DMA memory of different devices and protect the 681 system from misbehaving device drivers or hardware. 682 683 You can find out if your system has an AMD IOMMU if you look into 684 your BIOS for an option to enable it or if you have an IVRS ACPI 685 table. 686 687config AMD_IOMMU_STATS 688 bool "Export AMD IOMMU statistics to debugfs" 689 depends on AMD_IOMMU 690 select DEBUG_FS 691 ---help--- 692 This option enables code in the AMD IOMMU driver to collect various 693 statistics about whats happening in the driver and exports that 694 information to userspace via debugfs. 695 If unsure, say N. 696 697# need this always selected by IOMMU for the VIA workaround 698config SWIOTLB 699 def_bool y if X86_64 700 ---help--- 701 Support for software bounce buffers used on x86-64 systems 702 which don't have a hardware IOMMU (e.g. the current generation 703 of Intel's x86-64 CPUs). Using this PCI devices which can only 704 access 32-bits of memory can be used on systems with more than 705 3 GB of memory. If unsure, say Y. 706 707config IOMMU_HELPER 708 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU) 709 710config IOMMU_API 711 def_bool (AMD_IOMMU || DMAR) 712 713config MAXSMP 714 bool "Configure Maximum number of SMP Processors and NUMA Nodes" 715 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL 716 select CPUMASK_OFFSTACK 717 default n 718 ---help--- 719 Configure maximum number of CPUS and NUMA Nodes for this architecture. 720 If unsure, say N. 721 722config NR_CPUS 723 int "Maximum number of CPUs" if SMP && !MAXSMP 724 range 2 8 if SMP && X86_32 && !X86_BIGSMP 725 range 2 512 if SMP && !MAXSMP 726 default "1" if !SMP 727 default "4096" if MAXSMP 728 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000) 729 default "8" if SMP 730 ---help--- 731 This allows you to specify the maximum number of CPUs which this 732 kernel will support. The maximum supported value is 512 and the 733 minimum value which makes sense is 2. 734 735 This is purely to save memory - each supported CPU adds 736 approximately eight kilobytes to the kernel image. 737 738config SCHED_SMT 739 bool "SMT (Hyperthreading) scheduler support" 740 depends on X86_HT 741 ---help--- 742 SMT scheduler support improves the CPU scheduler's decision making 743 when dealing with Intel Pentium 4 chips with HyperThreading at a 744 cost of slightly increased overhead in some places. If unsure say 745 N here. 746 747config SCHED_MC 748 def_bool y 749 prompt "Multi-core scheduler support" 750 depends on X86_HT 751 ---help--- 752 Multi-core scheduler support improves the CPU scheduler's decision 753 making when dealing with multi-core CPU chips at a cost of slightly 754 increased overhead in some places. If unsure say N here. 755 756source "kernel/Kconfig.preempt" 757 758config X86_UP_APIC 759 bool "Local APIC support on uniprocessors" 760 depends on X86_32 && !SMP && !X86_32_NON_STANDARD 761 ---help--- 762 A local APIC (Advanced Programmable Interrupt Controller) is an 763 integrated interrupt controller in the CPU. If you have a single-CPU 764 system which has a processor with a local APIC, you can say Y here to 765 enable and use it. If you say Y here even though your machine doesn't 766 have a local APIC, then the kernel will still run with no slowdown at 767 all. The local APIC supports CPU-generated self-interrupts (timer, 768 performance counters), and the NMI watchdog which detects hard 769 lockups. 770 771config X86_UP_IOAPIC 772 bool "IO-APIC support on uniprocessors" 773 depends on X86_UP_APIC 774 ---help--- 775 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 776 SMP-capable replacement for PC-style interrupt controllers. Most 777 SMP systems and many recent uniprocessor systems have one. 778 779 If you have a single-CPU system with an IO-APIC, you can say Y here 780 to use it. If you say Y here even though your machine doesn't have 781 an IO-APIC, then the kernel will still run with no slowdown at all. 782 783config X86_LOCAL_APIC 784 def_bool y 785 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC 786 787config X86_IO_APIC 788 def_bool y 789 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC 790 791config X86_VISWS_APIC 792 def_bool y 793 depends on X86_32 && X86_VISWS 794 795config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 796 bool "Reroute for broken boot IRQs" 797 default n 798 depends on X86_IO_APIC 799 ---help--- 800 This option enables a workaround that fixes a source of 801 spurious interrupts. This is recommended when threaded 802 interrupt handling is used on systems where the generation of 803 superfluous "boot interrupts" cannot be disabled. 804 805 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 806 entry in the chipset's IO-APIC is masked (as, e.g. the RT 807 kernel does during interrupt handling). On chipsets where this 808 boot IRQ generation cannot be disabled, this workaround keeps 809 the original IRQ line masked so that only the equivalent "boot 810 IRQ" is delivered to the CPUs. The workaround also tells the 811 kernel to set up the IRQ handler on the boot IRQ line. In this 812 way only one interrupt is delivered to the kernel. Otherwise 813 the spurious second interrupt may cause the kernel to bring 814 down (vital) interrupt lines. 815 816 Only affects "broken" chipsets. Interrupt sharing may be 817 increased on these systems. 818 819config X86_MCE 820 bool "Machine Check / overheating reporting" 821 ---help--- 822 Machine Check support allows the processor to notify the 823 kernel if it detects a problem (e.g. overheating, data corruption). 824 The action the kernel takes depends on the severity of the problem, 825 ranging from warning messages to halting the machine. 826 827config X86_MCE_INTEL 828 def_bool y 829 prompt "Intel MCE features" 830 depends on X86_MCE && X86_LOCAL_APIC 831 ---help--- 832 Additional support for intel specific MCE features such as 833 the thermal monitor. 834 835config X86_MCE_AMD 836 def_bool y 837 prompt "AMD MCE features" 838 depends on X86_MCE && X86_LOCAL_APIC 839 ---help--- 840 Additional support for AMD specific MCE features such as 841 the DRAM Error Threshold. 842 843config X86_ANCIENT_MCE 844 def_bool n 845 depends on X86_32 && X86_MCE 846 prompt "Support for old Pentium 5 / WinChip machine checks" 847 ---help--- 848 Include support for machine check handling on old Pentium 5 or WinChip 849 systems. These typically need to be enabled explicitely on the command 850 line. 851 852config X86_MCE_THRESHOLD 853 depends on X86_MCE_AMD || X86_MCE_INTEL 854 bool 855 default y 856 857config X86_MCE_INJECT 858 depends on X86_MCE 859 tristate "Machine check injector support" 860 ---help--- 861 Provide support for injecting machine checks for testing purposes. 862 If you don't know what a machine check is and you don't do kernel 863 QA it is safe to say n. 864 865config X86_THERMAL_VECTOR 866 def_bool y 867 depends on X86_MCE_INTEL 868 869config VM86 870 bool "Enable VM86 support" if EMBEDDED 871 default y 872 depends on X86_32 873 ---help--- 874 This option is required by programs like DOSEMU to run 16-bit legacy 875 code on X86 processors. It also may be needed by software like 876 XFree86 to initialize some video cards via BIOS. Disabling this 877 option saves about 6k. 878 879config TOSHIBA 880 tristate "Toshiba Laptop support" 881 depends on X86_32 882 ---help--- 883 This adds a driver to safely access the System Management Mode of 884 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 885 not work on models with a Phoenix BIOS. The System Management Mode 886 is used to set the BIOS and power saving options on Toshiba portables. 887 888 For information on utilities to make use of this driver see the 889 Toshiba Linux utilities web site at: 890 <http://www.buzzard.org.uk/toshiba/>. 891 892 Say Y if you intend to run this kernel on a Toshiba portable. 893 Say N otherwise. 894 895config I8K 896 tristate "Dell laptop support" 897 ---help--- 898 This adds a driver to safely access the System Management Mode 899 of the CPU on the Dell Inspiron 8000. The System Management Mode 900 is used to read cpu temperature and cooling fan status and to 901 control the fans on the I8K portables. 902 903 This driver has been tested only on the Inspiron 8000 but it may 904 also work with other Dell laptops. You can force loading on other 905 models by passing the parameter `force=1' to the module. Use at 906 your own risk. 907 908 For information on utilities to make use of this driver see the 909 I8K Linux utilities web site at: 910 <http://people.debian.org/~dz/i8k/> 911 912 Say Y if you intend to run this kernel on a Dell Inspiron 8000. 913 Say N otherwise. 914 915config X86_REBOOTFIXUPS 916 bool "Enable X86 board specific fixups for reboot" 917 depends on X86_32 918 ---help--- 919 This enables chipset and/or board specific fixups to be done 920 in order to get reboot to work correctly. This is only needed on 921 some combinations of hardware and BIOS. The symptom, for which 922 this config is intended, is when reboot ends with a stalled/hung 923 system. 924 925 Currently, the only fixup is for the Geode machines using 926 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 927 928 Say Y if you want to enable the fixup. Currently, it's safe to 929 enable this option even if you don't need it. 930 Say N otherwise. 931 932config MICROCODE 933 tristate "/dev/cpu/microcode - microcode support" 934 select FW_LOADER 935 ---help--- 936 If you say Y here, you will be able to update the microcode on 937 certain Intel and AMD processors. The Intel support is for the 938 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, 939 Pentium 4, Xeon etc. The AMD support is for family 0x10 and 940 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra. 941 You will obviously need the actual microcode binary data itself 942 which is not shipped with the Linux kernel. 943 944 This option selects the general module only, you need to select 945 at least one vendor specific module as well. 946 947 To compile this driver as a module, choose M here: the 948 module will be called microcode. 949 950config MICROCODE_INTEL 951 bool "Intel microcode patch loading support" 952 depends on MICROCODE 953 default MICROCODE 954 select FW_LOADER 955 ---help--- 956 This options enables microcode patch loading support for Intel 957 processors. 958 959 For latest news and information on obtaining all the required 960 Intel ingredients for this driver, check: 961 <http://www.urbanmyth.org/microcode/>. 962 963config MICROCODE_AMD 964 bool "AMD microcode patch loading support" 965 depends on MICROCODE 966 select FW_LOADER 967 ---help--- 968 If you select this option, microcode patch loading support for AMD 969 processors will be enabled. 970 971config MICROCODE_OLD_INTERFACE 972 def_bool y 973 depends on MICROCODE 974 975config X86_MSR 976 tristate "/dev/cpu/*/msr - Model-specific register support" 977 ---help--- 978 This device gives privileged processes access to the x86 979 Model-Specific Registers (MSRs). It is a character device with 980 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 981 MSR accesses are directed to a specific CPU on multi-processor 982 systems. 983 984config X86_CPUID 985 tristate "/dev/cpu/*/cpuid - CPU information support" 986 ---help--- 987 This device gives processes access to the x86 CPUID instruction to 988 be executed on a specific processor. It is a character device 989 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 990 /dev/cpu/31/cpuid. 991 992config X86_CPU_DEBUG 993 tristate "/sys/kernel/debug/x86/cpu/* - CPU Debug support" 994 ---help--- 995 If you select this option, this will provide various x86 CPUs 996 information through debugfs. 997 998choice 999 prompt "High Memory Support" 1000 default HIGHMEM4G if !X86_NUMAQ 1001 default HIGHMEM64G if X86_NUMAQ 1002 depends on X86_32 1003 1004config NOHIGHMEM 1005 bool "off" 1006 depends on !X86_NUMAQ 1007 ---help--- 1008 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1009 However, the address space of 32-bit x86 processors is only 4 1010 Gigabytes large. That means that, if you have a large amount of 1011 physical memory, not all of it can be "permanently mapped" by the 1012 kernel. The physical memory that's not permanently mapped is called 1013 "high memory". 1014 1015 If you are compiling a kernel which will never run on a machine with 1016 more than 1 Gigabyte total physical RAM, answer "off" here (default 1017 choice and suitable for most users). This will result in a "3GB/1GB" 1018 split: 3GB are mapped so that each process sees a 3GB virtual memory 1019 space and the remaining part of the 4GB virtual memory space is used 1020 by the kernel to permanently map as much physical memory as 1021 possible. 1022 1023 If the machine has between 1 and 4 Gigabytes physical RAM, then 1024 answer "4GB" here. 1025 1026 If more than 4 Gigabytes is used then answer "64GB" here. This 1027 selection turns Intel PAE (Physical Address Extension) mode on. 1028 PAE implements 3-level paging on IA32 processors. PAE is fully 1029 supported by Linux, PAE mode is implemented on all recent Intel 1030 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1031 then the kernel will not boot on CPUs that don't support PAE! 1032 1033 The actual amount of total physical memory will either be 1034 auto detected or can be forced by using a kernel command line option 1035 such as "mem=256M". (Try "man bootparam" or see the documentation of 1036 your boot loader (lilo or loadlin) about how to pass options to the 1037 kernel at boot time.) 1038 1039 If unsure, say "off". 1040 1041config HIGHMEM4G 1042 bool "4GB" 1043 depends on !X86_NUMAQ 1044 ---help--- 1045 Select this if you have a 32-bit processor and between 1 and 4 1046 gigabytes of physical RAM. 1047 1048config HIGHMEM64G 1049 bool "64GB" 1050 depends on !M386 && !M486 1051 select X86_PAE 1052 ---help--- 1053 Select this if you have a 32-bit processor and more than 4 1054 gigabytes of physical RAM. 1055 1056endchoice 1057 1058choice 1059 depends on EXPERIMENTAL 1060 prompt "Memory split" if EMBEDDED 1061 default VMSPLIT_3G 1062 depends on X86_32 1063 ---help--- 1064 Select the desired split between kernel and user memory. 1065 1066 If the address range available to the kernel is less than the 1067 physical memory installed, the remaining memory will be available 1068 as "high memory". Accessing high memory is a little more costly 1069 than low memory, as it needs to be mapped into the kernel first. 1070 Note that increasing the kernel address space limits the range 1071 available to user programs, making the address space there 1072 tighter. Selecting anything other than the default 3G/1G split 1073 will also likely make your kernel incompatible with binary-only 1074 kernel modules. 1075 1076 If you are not absolutely sure what you are doing, leave this 1077 option alone! 1078 1079 config VMSPLIT_3G 1080 bool "3G/1G user/kernel split" 1081 config VMSPLIT_3G_OPT 1082 depends on !X86_PAE 1083 bool "3G/1G user/kernel split (for full 1G low memory)" 1084 config VMSPLIT_2G 1085 bool "2G/2G user/kernel split" 1086 config VMSPLIT_2G_OPT 1087 depends on !X86_PAE 1088 bool "2G/2G user/kernel split (for full 2G low memory)" 1089 config VMSPLIT_1G 1090 bool "1G/3G user/kernel split" 1091endchoice 1092 1093config PAGE_OFFSET 1094 hex 1095 default 0xB0000000 if VMSPLIT_3G_OPT 1096 default 0x80000000 if VMSPLIT_2G 1097 default 0x78000000 if VMSPLIT_2G_OPT 1098 default 0x40000000 if VMSPLIT_1G 1099 default 0xC0000000 1100 depends on X86_32 1101 1102config HIGHMEM 1103 def_bool y 1104 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1105 1106config X86_PAE 1107 bool "PAE (Physical Address Extension) Support" 1108 depends on X86_32 && !HIGHMEM4G 1109 ---help--- 1110 PAE is required for NX support, and furthermore enables 1111 larger swapspace support for non-overcommit purposes. It 1112 has the cost of more pagetable lookup overhead, and also 1113 consumes more pagetable space per process. 1114 1115config ARCH_PHYS_ADDR_T_64BIT 1116 def_bool X86_64 || X86_PAE 1117 1118config DIRECT_GBPAGES 1119 bool "Enable 1GB pages for kernel pagetables" if EMBEDDED 1120 default y 1121 depends on X86_64 1122 ---help--- 1123 Allow the kernel linear mapping to use 1GB pages on CPUs that 1124 support it. This can improve the kernel's performance a tiny bit by 1125 reducing TLB pressure. If in doubt, say "Y". 1126 1127# Common NUMA Features 1128config NUMA 1129 bool "Numa Memory Allocation and Scheduler Support" 1130 depends on SMP 1131 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL) 1132 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP) 1133 ---help--- 1134 Enable NUMA (Non Uniform Memory Access) support. 1135 1136 The kernel will try to allocate memory used by a CPU on the 1137 local memory controller of the CPU and add some more 1138 NUMA awareness to the kernel. 1139 1140 For 64-bit this is recommended if the system is Intel Core i7 1141 (or later), AMD Opteron, or EM64T NUMA. 1142 1143 For 32-bit this is only needed on (rare) 32-bit-only platforms 1144 that support NUMA topologies, such as NUMAQ / Summit, or if you 1145 boot a 32-bit kernel on a 64-bit NUMA platform. 1146 1147 Otherwise, you should say N. 1148 1149comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI" 1150 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI) 1151 1152config K8_NUMA 1153 def_bool y 1154 prompt "Old style AMD Opteron NUMA detection" 1155 depends on X86_64 && NUMA && PCI 1156 ---help--- 1157 Enable K8 NUMA node topology detection. You should say Y here if 1158 you have a multi processor AMD K8 system. This uses an old 1159 method to read the NUMA configuration directly from the builtin 1160 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA 1161 instead, which also takes priority if both are compiled in. 1162 1163config X86_64_ACPI_NUMA 1164 def_bool y 1165 prompt "ACPI NUMA detection" 1166 depends on X86_64 && NUMA && ACPI && PCI 1167 select ACPI_NUMA 1168 ---help--- 1169 Enable ACPI SRAT based node topology detection. 1170 1171# Some NUMA nodes have memory ranges that span 1172# other nodes. Even though a pfn is valid and 1173# between a node's start and end pfns, it may not 1174# reside on that node. See memmap_init_zone() 1175# for details. 1176config NODES_SPAN_OTHER_NODES 1177 def_bool y 1178 depends on X86_64_ACPI_NUMA 1179 1180config NUMA_EMU 1181 bool "NUMA emulation" 1182 depends on X86_64 && NUMA 1183 ---help--- 1184 Enable NUMA emulation. A flat machine will be split 1185 into virtual nodes when booted with "numa=fake=N", where N is the 1186 number of nodes. This is only useful for debugging. 1187 1188config NODES_SHIFT 1189 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1190 range 1 9 1191 default "9" if MAXSMP 1192 default "6" if X86_64 1193 default "4" if X86_NUMAQ 1194 default "3" 1195 depends on NEED_MULTIPLE_NODES 1196 ---help--- 1197 Specify the maximum number of NUMA Nodes available on the target 1198 system. Increases memory reserved to accommodate various tables. 1199 1200config HAVE_ARCH_BOOTMEM 1201 def_bool y 1202 depends on X86_32 && NUMA 1203 1204config ARCH_HAVE_MEMORY_PRESENT 1205 def_bool y 1206 depends on X86_32 && DISCONTIGMEM 1207 1208config NEED_NODE_MEMMAP_SIZE 1209 def_bool y 1210 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1211 1212config HAVE_ARCH_ALLOC_REMAP 1213 def_bool y 1214 depends on X86_32 && NUMA 1215 1216config ARCH_FLATMEM_ENABLE 1217 def_bool y 1218 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA 1219 1220config ARCH_DISCONTIGMEM_ENABLE 1221 def_bool y 1222 depends on NUMA && X86_32 1223 1224config ARCH_DISCONTIGMEM_DEFAULT 1225 def_bool y 1226 depends on NUMA && X86_32 1227 1228config ARCH_PROC_KCORE_TEXT 1229 def_bool y 1230 depends on X86_64 && PROC_KCORE 1231 1232config ARCH_SPARSEMEM_DEFAULT 1233 def_bool y 1234 depends on X86_64 1235 1236config ARCH_SPARSEMEM_ENABLE 1237 def_bool y 1238 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD 1239 select SPARSEMEM_STATIC if X86_32 1240 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1241 1242config ARCH_SELECT_MEMORY_MODEL 1243 def_bool y 1244 depends on ARCH_SPARSEMEM_ENABLE 1245 1246config ARCH_MEMORY_PROBE 1247 def_bool X86_64 1248 depends on MEMORY_HOTPLUG 1249 1250config ILLEGAL_POINTER_VALUE 1251 hex 1252 default 0 if X86_32 1253 default 0xdead000000000000 if X86_64 1254 1255source "mm/Kconfig" 1256 1257config HIGHPTE 1258 bool "Allocate 3rd-level pagetables from highmem" 1259 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G) 1260 ---help--- 1261 The VM uses one page table entry for each page of physical memory. 1262 For systems with a lot of RAM, this can be wasteful of precious 1263 low memory. Setting this option will put user-space page table 1264 entries in high memory. 1265 1266config X86_CHECK_BIOS_CORRUPTION 1267 bool "Check for low memory corruption" 1268 ---help--- 1269 Periodically check for memory corruption in low memory, which 1270 is suspected to be caused by BIOS. Even when enabled in the 1271 configuration, it is disabled at runtime. Enable it by 1272 setting "memory_corruption_check=1" on the kernel command 1273 line. By default it scans the low 64k of memory every 60 1274 seconds; see the memory_corruption_check_size and 1275 memory_corruption_check_period parameters in 1276 Documentation/kernel-parameters.txt to adjust this. 1277 1278 When enabled with the default parameters, this option has 1279 almost no overhead, as it reserves a relatively small amount 1280 of memory and scans it infrequently. It both detects corruption 1281 and prevents it from affecting the running system. 1282 1283 It is, however, intended as a diagnostic tool; if repeatable 1284 BIOS-originated corruption always affects the same memory, 1285 you can use memmap= to prevent the kernel from using that 1286 memory. 1287 1288config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1289 bool "Set the default setting of memory_corruption_check" 1290 depends on X86_CHECK_BIOS_CORRUPTION 1291 default y 1292 ---help--- 1293 Set whether the default state of memory_corruption_check is 1294 on or off. 1295 1296config X86_RESERVE_LOW_64K 1297 bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen" 1298 default y 1299 ---help--- 1300 Reserve the first 64K of physical RAM on BIOSes that are known 1301 to potentially corrupt that memory range. A numbers of BIOSes are 1302 known to utilize this area during suspend/resume, so it must not 1303 be used by the kernel. 1304 1305 Set this to N if you are absolutely sure that you trust the BIOS 1306 to get all its memory reservations and usages right. 1307 1308 If you have doubts about the BIOS (e.g. suspend/resume does not 1309 work or there's kernel crashes after certain hardware hotplug 1310 events) and it's not AMI or Phoenix, then you might want to enable 1311 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical 1312 corruption patterns. 1313 1314 Say Y if unsure. 1315 1316config MATH_EMULATION 1317 bool 1318 prompt "Math emulation" if X86_32 1319 ---help--- 1320 Linux can emulate a math coprocessor (used for floating point 1321 operations) if you don't have one. 486DX and Pentium processors have 1322 a math coprocessor built in, 486SX and 386 do not, unless you added 1323 a 487DX or 387, respectively. (The messages during boot time can 1324 give you some hints here ["man dmesg"].) Everyone needs either a 1325 coprocessor or this emulation. 1326 1327 If you don't have a math coprocessor, you need to say Y here; if you 1328 say Y here even though you have a coprocessor, the coprocessor will 1329 be used nevertheless. (This behavior can be changed with the kernel 1330 command line option "no387", which comes handy if your coprocessor 1331 is broken. Try "man bootparam" or see the documentation of your boot 1332 loader (lilo or loadlin) about how to pass options to the kernel at 1333 boot time.) This means that it is a good idea to say Y here if you 1334 intend to use this kernel on different machines. 1335 1336 More information about the internals of the Linux math coprocessor 1337 emulation can be found in <file:arch/x86/math-emu/README>. 1338 1339 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1340 kernel, it won't hurt. 1341 1342config MTRR 1343 bool 1344 default y 1345 prompt "MTRR (Memory Type Range Register) support" if EMBEDDED 1346 ---help--- 1347 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1348 the Memory Type Range Registers (MTRRs) may be used to control 1349 processor access to memory ranges. This is most useful if you have 1350 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1351 allows bus write transfers to be combined into a larger transfer 1352 before bursting over the PCI/AGP bus. This can increase performance 1353 of image write operations 2.5 times or more. Saying Y here creates a 1354 /proc/mtrr file which may be used to manipulate your processor's 1355 MTRRs. Typically the X server should use this. 1356 1357 This code has a reasonably generic interface so that similar 1358 control registers on other processors can be easily supported 1359 as well: 1360 1361 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1362 Registers (ARRs) which provide a similar functionality to MTRRs. For 1363 these, the ARRs are used to emulate the MTRRs. 1364 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1365 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1366 write-combining. All of these processors are supported by this code 1367 and it makes sense to say Y here if you have one of them. 1368 1369 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1370 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1371 can lead to all sorts of problems, so it's good to say Y here. 1372 1373 You can safely say Y even if your machine doesn't have MTRRs, you'll 1374 just add about 9 KB to your kernel. 1375 1376 See <file:Documentation/x86/mtrr.txt> for more information. 1377 1378config MTRR_SANITIZER 1379 def_bool y 1380 prompt "MTRR cleanup support" 1381 depends on MTRR 1382 ---help--- 1383 Convert MTRR layout from continuous to discrete, so X drivers can 1384 add writeback entries. 1385 1386 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1387 The largest mtrr entry size for a continuous block can be set with 1388 mtrr_chunk_size. 1389 1390 If unsure, say Y. 1391 1392config MTRR_SANITIZER_ENABLE_DEFAULT 1393 int "MTRR cleanup enable value (0-1)" 1394 range 0 1 1395 default "0" 1396 depends on MTRR_SANITIZER 1397 ---help--- 1398 Enable mtrr cleanup default value 1399 1400config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1401 int "MTRR cleanup spare reg num (0-7)" 1402 range 0 7 1403 default "1" 1404 depends on MTRR_SANITIZER 1405 ---help--- 1406 mtrr cleanup spare entries default, it can be changed via 1407 mtrr_spare_reg_nr=N on the kernel command line. 1408 1409config X86_PAT 1410 bool 1411 default y 1412 prompt "x86 PAT support" if EMBEDDED 1413 depends on MTRR 1414 ---help--- 1415 Use PAT attributes to setup page level cache control. 1416 1417 PATs are the modern equivalents of MTRRs and are much more 1418 flexible than MTRRs. 1419 1420 Say N here if you see bootup problems (boot crash, boot hang, 1421 spontaneous reboots) or a non-working video driver. 1422 1423 If unsure, say Y. 1424 1425config ARCH_USES_PG_UNCACHED 1426 def_bool y 1427 depends on X86_PAT 1428 1429config EFI 1430 bool "EFI runtime service support" 1431 depends on ACPI 1432 ---help--- 1433 This enables the kernel to use EFI runtime services that are 1434 available (such as the EFI variable services). 1435 1436 This option is only useful on systems that have EFI firmware. 1437 In addition, you should use the latest ELILO loader available 1438 at <http://elilo.sourceforge.net> in order to take advantage 1439 of EFI runtime services. However, even with this option, the 1440 resultant kernel should continue to boot on existing non-EFI 1441 platforms. 1442 1443config SECCOMP 1444 def_bool y 1445 prompt "Enable seccomp to safely compute untrusted bytecode" 1446 ---help--- 1447 This kernel feature is useful for number crunching applications 1448 that may need to compute untrusted bytecode during their 1449 execution. By using pipes or other transports made available to 1450 the process as file descriptors supporting the read/write 1451 syscalls, it's possible to isolate those applications in 1452 their own address space using seccomp. Once seccomp is 1453 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1454 and the task is only allowed to execute a few safe syscalls 1455 defined by each seccomp mode. 1456 1457 If unsure, say Y. Only embedded should say N here. 1458 1459config CC_STACKPROTECTOR 1460 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)" 1461 ---help--- 1462 This option turns on the -fstack-protector GCC feature. This 1463 feature puts, at the beginning of functions, a canary value on 1464 the stack just before the return address, and validates 1465 the value just before actually returning. Stack based buffer 1466 overflows (that need to overwrite this return address) now also 1467 overwrite the canary, which gets detected and the attack is then 1468 neutralized via a kernel panic. 1469 1470 This feature requires gcc version 4.2 or above, or a distribution 1471 gcc with the feature backported. Older versions are automatically 1472 detected and for those versions, this configuration option is 1473 ignored. (and a warning is printed during bootup) 1474 1475source kernel/Kconfig.hz 1476 1477config KEXEC 1478 bool "kexec system call" 1479 ---help--- 1480 kexec is a system call that implements the ability to shutdown your 1481 current kernel, and to start another kernel. It is like a reboot 1482 but it is independent of the system firmware. And like a reboot 1483 you can start any kernel with it, not just Linux. 1484 1485 The name comes from the similarity to the exec system call. 1486 1487 It is an ongoing process to be certain the hardware in a machine 1488 is properly shutdown, so do not be surprised if this code does not 1489 initially work for you. It may help to enable device hotplugging 1490 support. As of this writing the exact hardware interface is 1491 strongly in flux, so no good recommendation can be made. 1492 1493config CRASH_DUMP 1494 bool "kernel crash dumps" 1495 depends on X86_64 || (X86_32 && HIGHMEM) 1496 ---help--- 1497 Generate crash dump after being started by kexec. 1498 This should be normally only set in special crash dump kernels 1499 which are loaded in the main kernel with kexec-tools into 1500 a specially reserved region and then later executed after 1501 a crash by kdump/kexec. The crash dump kernel must be compiled 1502 to a memory address not used by the main kernel or BIOS using 1503 PHYSICAL_START, or it must be built as a relocatable image 1504 (CONFIG_RELOCATABLE=y). 1505 For more details see Documentation/kdump/kdump.txt 1506 1507config KEXEC_JUMP 1508 bool "kexec jump (EXPERIMENTAL)" 1509 depends on EXPERIMENTAL 1510 depends on KEXEC && HIBERNATION 1511 ---help--- 1512 Jump between original kernel and kexeced kernel and invoke 1513 code in physical address mode via KEXEC 1514 1515config PHYSICAL_START 1516 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP) 1517 default "0x1000000" 1518 ---help--- 1519 This gives the physical address where the kernel is loaded. 1520 1521 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1522 bzImage will decompress itself to above physical address and 1523 run from there. Otherwise, bzImage will run from the address where 1524 it has been loaded by the boot loader and will ignore above physical 1525 address. 1526 1527 In normal kdump cases one does not have to set/change this option 1528 as now bzImage can be compiled as a completely relocatable image 1529 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1530 address. This option is mainly useful for the folks who don't want 1531 to use a bzImage for capturing the crash dump and want to use a 1532 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1533 to be specifically compiled to run from a specific memory area 1534 (normally a reserved region) and this option comes handy. 1535 1536 So if you are using bzImage for capturing the crash dump, 1537 leave the value here unchanged to 0x1000000 and set 1538 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1539 for capturing the crash dump change this value to start of 1540 the reserved region. In other words, it can be set based on 1541 the "X" value as specified in the "crashkernel=YM@XM" 1542 command line boot parameter passed to the panic-ed 1543 kernel. Please take a look at Documentation/kdump/kdump.txt 1544 for more details about crash dumps. 1545 1546 Usage of bzImage for capturing the crash dump is recommended as 1547 one does not have to build two kernels. Same kernel can be used 1548 as production kernel and capture kernel. Above option should have 1549 gone away after relocatable bzImage support is introduced. But it 1550 is present because there are users out there who continue to use 1551 vmlinux for dump capture. This option should go away down the 1552 line. 1553 1554 Don't change this unless you know what you are doing. 1555 1556config RELOCATABLE 1557 bool "Build a relocatable kernel" 1558 default y 1559 ---help--- 1560 This builds a kernel image that retains relocation information 1561 so it can be loaded someplace besides the default 1MB. 1562 The relocations tend to make the kernel binary about 10% larger, 1563 but are discarded at runtime. 1564 1565 One use is for the kexec on panic case where the recovery kernel 1566 must live at a different physical address than the primary 1567 kernel. 1568 1569 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1570 it has been loaded at and the compile time physical address 1571 (CONFIG_PHYSICAL_START) is ignored. 1572 1573# Relocation on x86-32 needs some additional build support 1574config X86_NEED_RELOCS 1575 def_bool y 1576 depends on X86_32 && RELOCATABLE 1577 1578config PHYSICAL_ALIGN 1579 hex 1580 prompt "Alignment value to which kernel should be aligned" if X86_32 1581 default "0x1000000" 1582 range 0x2000 0x1000000 1583 ---help--- 1584 This value puts the alignment restrictions on physical address 1585 where kernel is loaded and run from. Kernel is compiled for an 1586 address which meets above alignment restriction. 1587 1588 If bootloader loads the kernel at a non-aligned address and 1589 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1590 address aligned to above value and run from there. 1591 1592 If bootloader loads the kernel at a non-aligned address and 1593 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1594 load address and decompress itself to the address it has been 1595 compiled for and run from there. The address for which kernel is 1596 compiled already meets above alignment restrictions. Hence the 1597 end result is that kernel runs from a physical address meeting 1598 above alignment restrictions. 1599 1600 Don't change this unless you know what you are doing. 1601 1602config HOTPLUG_CPU 1603 bool "Support for hot-pluggable CPUs" 1604 depends on SMP && HOTPLUG 1605 ---help--- 1606 Say Y here to allow turning CPUs off and on. CPUs can be 1607 controlled through /sys/devices/system/cpu. 1608 ( Note: power management support will enable this option 1609 automatically on SMP systems. ) 1610 Say N if you want to disable CPU hotplug. 1611 1612config COMPAT_VDSO 1613 def_bool y 1614 prompt "Compat VDSO support" 1615 depends on X86_32 || IA32_EMULATION 1616 ---help--- 1617 Map the 32-bit VDSO to the predictable old-style address too. 1618 1619 Say N here if you are running a sufficiently recent glibc 1620 version (2.3.3 or later), to remove the high-mapped 1621 VDSO mapping and to exclusively use the randomized VDSO. 1622 1623 If unsure, say Y. 1624 1625config CMDLINE_BOOL 1626 bool "Built-in kernel command line" 1627 default n 1628 ---help--- 1629 Allow for specifying boot arguments to the kernel at 1630 build time. On some systems (e.g. embedded ones), it is 1631 necessary or convenient to provide some or all of the 1632 kernel boot arguments with the kernel itself (that is, 1633 to not rely on the boot loader to provide them.) 1634 1635 To compile command line arguments into the kernel, 1636 set this option to 'Y', then fill in the 1637 the boot arguments in CONFIG_CMDLINE. 1638 1639 Systems with fully functional boot loaders (i.e. non-embedded) 1640 should leave this option set to 'N'. 1641 1642config CMDLINE 1643 string "Built-in kernel command string" 1644 depends on CMDLINE_BOOL 1645 default "" 1646 ---help--- 1647 Enter arguments here that should be compiled into the kernel 1648 image and used at boot time. If the boot loader provides a 1649 command line at boot time, it is appended to this string to 1650 form the full kernel command line, when the system boots. 1651 1652 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 1653 change this behavior. 1654 1655 In most cases, the command line (whether built-in or provided 1656 by the boot loader) should specify the device for the root 1657 file system. 1658 1659config CMDLINE_OVERRIDE 1660 bool "Built-in command line overrides boot loader arguments" 1661 default n 1662 depends on CMDLINE_BOOL 1663 ---help--- 1664 Set this option to 'Y' to have the kernel ignore the boot loader 1665 command line, and use ONLY the built-in command line. 1666 1667 This is used to work around broken boot loaders. This should 1668 be set to 'N' under normal conditions. 1669 1670endmenu 1671 1672config ARCH_ENABLE_MEMORY_HOTPLUG 1673 def_bool y 1674 depends on X86_64 || (X86_32 && HIGHMEM) 1675 1676config ARCH_ENABLE_MEMORY_HOTREMOVE 1677 def_bool y 1678 depends on MEMORY_HOTPLUG 1679 1680config HAVE_ARCH_EARLY_PFN_TO_NID 1681 def_bool X86_64 1682 depends on NUMA 1683 1684menu "Power management and ACPI options" 1685 1686config ARCH_HIBERNATION_HEADER 1687 def_bool y 1688 depends on X86_64 && HIBERNATION 1689 1690source "kernel/power/Kconfig" 1691 1692source "drivers/acpi/Kconfig" 1693 1694source "drivers/sfi/Kconfig" 1695 1696config X86_APM_BOOT 1697 bool 1698 default y 1699 depends on APM || APM_MODULE 1700 1701menuconfig APM 1702 tristate "APM (Advanced Power Management) BIOS support" 1703 depends on X86_32 && PM_SLEEP 1704 ---help--- 1705 APM is a BIOS specification for saving power using several different 1706 techniques. This is mostly useful for battery powered laptops with 1707 APM compliant BIOSes. If you say Y here, the system time will be 1708 reset after a RESUME operation, the /proc/apm device will provide 1709 battery status information, and user-space programs will receive 1710 notification of APM "events" (e.g. battery status change). 1711 1712 If you select "Y" here, you can disable actual use of the APM 1713 BIOS by passing the "apm=off" option to the kernel at boot time. 1714 1715 Note that the APM support is almost completely disabled for 1716 machines with more than one CPU. 1717 1718 In order to use APM, you will need supporting software. For location 1719 and more information, read <file:Documentation/power/pm.txt> and the 1720 Battery Powered Linux mini-HOWTO, available from 1721 <http://www.tldp.org/docs.html#howto>. 1722 1723 This driver does not spin down disk drives (see the hdparm(8) 1724 manpage ("man 8 hdparm") for that), and it doesn't turn off 1725 VESA-compliant "green" monitors. 1726 1727 This driver does not support the TI 4000M TravelMate and the ACER 1728 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1729 desktop machines also don't have compliant BIOSes, and this driver 1730 may cause those machines to panic during the boot phase. 1731 1732 Generally, if you don't have a battery in your machine, there isn't 1733 much point in using this driver and you should say N. If you get 1734 random kernel OOPSes or reboots that don't seem to be related to 1735 anything, try disabling/enabling this option (or disabling/enabling 1736 APM in your BIOS). 1737 1738 Some other things you should try when experiencing seemingly random, 1739 "weird" problems: 1740 1741 1) make sure that you have enough swap space and that it is 1742 enabled. 1743 2) pass the "no-hlt" option to the kernel 1744 3) switch on floating point emulation in the kernel and pass 1745 the "no387" option to the kernel 1746 4) pass the "floppy=nodma" option to the kernel 1747 5) pass the "mem=4M" option to the kernel (thereby disabling 1748 all but the first 4 MB of RAM) 1749 6) make sure that the CPU is not over clocked. 1750 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1751 8) disable the cache from your BIOS settings 1752 9) install a fan for the video card or exchange video RAM 1753 10) install a better fan for the CPU 1754 11) exchange RAM chips 1755 12) exchange the motherboard. 1756 1757 To compile this driver as a module, choose M here: the 1758 module will be called apm. 1759 1760if APM 1761 1762config APM_IGNORE_USER_SUSPEND 1763 bool "Ignore USER SUSPEND" 1764 ---help--- 1765 This option will ignore USER SUSPEND requests. On machines with a 1766 compliant APM BIOS, you want to say N. However, on the NEC Versa M 1767 series notebooks, it is necessary to say Y because of a BIOS bug. 1768 1769config APM_DO_ENABLE 1770 bool "Enable PM at boot time" 1771 ---help--- 1772 Enable APM features at boot time. From page 36 of the APM BIOS 1773 specification: "When disabled, the APM BIOS does not automatically 1774 power manage devices, enter the Standby State, enter the Suspend 1775 State, or take power saving steps in response to CPU Idle calls." 1776 This driver will make CPU Idle calls when Linux is idle (unless this 1777 feature is turned off -- see "Do CPU IDLE calls", below). This 1778 should always save battery power, but more complicated APM features 1779 will be dependent on your BIOS implementation. You may need to turn 1780 this option off if your computer hangs at boot time when using APM 1781 support, or if it beeps continuously instead of suspending. Turn 1782 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1783 T400CDT. This is off by default since most machines do fine without 1784 this feature. 1785 1786config APM_CPU_IDLE 1787 bool "Make CPU Idle calls when idle" 1788 ---help--- 1789 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 1790 On some machines, this can activate improved power savings, such as 1791 a slowed CPU clock rate, when the machine is idle. These idle calls 1792 are made after the idle loop has run for some length of time (e.g., 1793 333 mS). On some machines, this will cause a hang at boot time or 1794 whenever the CPU becomes idle. (On machines with more than one CPU, 1795 this option does nothing.) 1796 1797config APM_DISPLAY_BLANK 1798 bool "Enable console blanking using APM" 1799 ---help--- 1800 Enable console blanking using the APM. Some laptops can use this to 1801 turn off the LCD backlight when the screen blanker of the Linux 1802 virtual console blanks the screen. Note that this is only used by 1803 the virtual console screen blanker, and won't turn off the backlight 1804 when using the X Window system. This also doesn't have anything to 1805 do with your VESA-compliant power-saving monitor. Further, this 1806 option doesn't work for all laptops -- it might not turn off your 1807 backlight at all, or it might print a lot of errors to the console, 1808 especially if you are using gpm. 1809 1810config APM_ALLOW_INTS 1811 bool "Allow interrupts during APM BIOS calls" 1812 ---help--- 1813 Normally we disable external interrupts while we are making calls to 1814 the APM BIOS as a measure to lessen the effects of a badly behaving 1815 BIOS implementation. The BIOS should reenable interrupts if it 1816 needs to. Unfortunately, some BIOSes do not -- especially those in 1817 many of the newer IBM Thinkpads. If you experience hangs when you 1818 suspend, try setting this to Y. Otherwise, say N. 1819 1820endif # APM 1821 1822source "arch/x86/kernel/cpu/cpufreq/Kconfig" 1823 1824source "drivers/cpuidle/Kconfig" 1825 1826source "drivers/idle/Kconfig" 1827 1828endmenu 1829 1830 1831menu "Bus options (PCI etc.)" 1832 1833config PCI 1834 bool "PCI support" 1835 default y 1836 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC) 1837 ---help--- 1838 Find out whether you have a PCI motherboard. PCI is the name of a 1839 bus system, i.e. the way the CPU talks to the other stuff inside 1840 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 1841 VESA. If you have PCI, say Y, otherwise N. 1842 1843choice 1844 prompt "PCI access mode" 1845 depends on X86_32 && PCI 1846 default PCI_GOANY 1847 ---help--- 1848 On PCI systems, the BIOS can be used to detect the PCI devices and 1849 determine their configuration. However, some old PCI motherboards 1850 have BIOS bugs and may crash if this is done. Also, some embedded 1851 PCI-based systems don't have any BIOS at all. Linux can also try to 1852 detect the PCI hardware directly without using the BIOS. 1853 1854 With this option, you can specify how Linux should detect the 1855 PCI devices. If you choose "BIOS", the BIOS will be used, 1856 if you choose "Direct", the BIOS won't be used, and if you 1857 choose "MMConfig", then PCI Express MMCONFIG will be used. 1858 If you choose "Any", the kernel will try MMCONFIG, then the 1859 direct access method and falls back to the BIOS if that doesn't 1860 work. If unsure, go with the default, which is "Any". 1861 1862config PCI_GOBIOS 1863 bool "BIOS" 1864 1865config PCI_GOMMCONFIG 1866 bool "MMConfig" 1867 1868config PCI_GODIRECT 1869 bool "Direct" 1870 1871config PCI_GOOLPC 1872 bool "OLPC" 1873 depends on OLPC 1874 1875config PCI_GOANY 1876 bool "Any" 1877 1878endchoice 1879 1880config PCI_BIOS 1881 def_bool y 1882 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 1883 1884# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 1885config PCI_DIRECT 1886 def_bool y 1887 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC)) 1888 1889config PCI_MMCONFIG 1890 def_bool y 1891 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 1892 1893config PCI_OLPC 1894 def_bool y 1895 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 1896 1897config PCI_DOMAINS 1898 def_bool y 1899 depends on PCI 1900 1901config PCI_MMCONFIG 1902 bool "Support mmconfig PCI config space access" 1903 depends on X86_64 && PCI && ACPI 1904 1905config DMAR 1906 bool "Support for DMA Remapping Devices (EXPERIMENTAL)" 1907 depends on PCI_MSI && ACPI && EXPERIMENTAL 1908 help 1909 DMA remapping (DMAR) devices support enables independent address 1910 translations for Direct Memory Access (DMA) from devices. 1911 These DMA remapping devices are reported via ACPI tables 1912 and include PCI device scope covered by these DMA 1913 remapping devices. 1914 1915config DMAR_DEFAULT_ON 1916 def_bool y 1917 prompt "Enable DMA Remapping Devices by default" 1918 depends on DMAR 1919 help 1920 Selecting this option will enable a DMAR device at boot time if 1921 one is found. If this option is not selected, DMAR support can 1922 be enabled by passing intel_iommu=on to the kernel. It is 1923 recommended you say N here while the DMAR code remains 1924 experimental. 1925 1926config DMAR_BROKEN_GFX_WA 1927 def_bool n 1928 prompt "Workaround broken graphics drivers (going away soon)" 1929 depends on DMAR && BROKEN 1930 ---help--- 1931 Current Graphics drivers tend to use physical address 1932 for DMA and avoid using DMA APIs. Setting this config 1933 option permits the IOMMU driver to set a unity map for 1934 all the OS-visible memory. Hence the driver can continue 1935 to use physical addresses for DMA, at least until this 1936 option is removed in the 2.6.32 kernel. 1937 1938config DMAR_FLOPPY_WA 1939 def_bool y 1940 depends on DMAR 1941 ---help--- 1942 Floppy disk drivers are known to bypass DMA API calls 1943 thereby failing to work when IOMMU is enabled. This 1944 workaround will setup a 1:1 mapping for the first 1945 16MiB to make floppy (an ISA device) work. 1946 1947config INTR_REMAP 1948 bool "Support for Interrupt Remapping (EXPERIMENTAL)" 1949 depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL 1950 ---help--- 1951 Supports Interrupt remapping for IO-APIC and MSI devices. 1952 To use x2apic mode in the CPU's which support x2APIC enhancements or 1953 to support platforms with CPU's having > 8 bit APIC ID, say Y. 1954 1955source "drivers/pci/pcie/Kconfig" 1956 1957source "drivers/pci/Kconfig" 1958 1959# x86_64 have no ISA slots, but do have ISA-style DMA. 1960config ISA_DMA_API 1961 def_bool y 1962 1963if X86_32 1964 1965config ISA 1966 bool "ISA support" 1967 ---help--- 1968 Find out whether you have ISA slots on your motherboard. ISA is the 1969 name of a bus system, i.e. the way the CPU talks to the other stuff 1970 inside your box. Other bus systems are PCI, EISA, MicroChannel 1971 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 1972 newer boards don't support it. If you have ISA, say Y, otherwise N. 1973 1974config EISA 1975 bool "EISA support" 1976 depends on ISA 1977 ---help--- 1978 The Extended Industry Standard Architecture (EISA) bus was 1979 developed as an open alternative to the IBM MicroChannel bus. 1980 1981 The EISA bus provided some of the features of the IBM MicroChannel 1982 bus while maintaining backward compatibility with cards made for 1983 the older ISA bus. The EISA bus saw limited use between 1988 and 1984 1995 when it was made obsolete by the PCI bus. 1985 1986 Say Y here if you are building a kernel for an EISA-based machine. 1987 1988 Otherwise, say N. 1989 1990source "drivers/eisa/Kconfig" 1991 1992config MCA 1993 bool "MCA support" 1994 ---help--- 1995 MicroChannel Architecture is found in some IBM PS/2 machines and 1996 laptops. It is a bus system similar to PCI or ISA. See 1997 <file:Documentation/mca.txt> (and especially the web page given 1998 there) before attempting to build an MCA bus kernel. 1999 2000source "drivers/mca/Kconfig" 2001 2002config SCx200 2003 tristate "NatSemi SCx200 support" 2004 ---help--- 2005 This provides basic support for National Semiconductor's 2006 (now AMD's) Geode processors. The driver probes for the 2007 PCI-IDs of several on-chip devices, so its a good dependency 2008 for other scx200_* drivers. 2009 2010 If compiled as a module, the driver is named scx200. 2011 2012config SCx200HR_TIMER 2013 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2014 depends on SCx200 && GENERIC_TIME 2015 default y 2016 ---help--- 2017 This driver provides a clocksource built upon the on-chip 2018 27MHz high-resolution timer. Its also a workaround for 2019 NSC Geode SC-1100's buggy TSC, which loses time when the 2020 processor goes idle (as is done by the scheduler). The 2021 other workaround is idle=poll boot option. 2022 2023config OLPC 2024 bool "One Laptop Per Child support" 2025 select GPIOLIB 2026 default n 2027 ---help--- 2028 Add support for detecting the unique features of the OLPC 2029 XO hardware. 2030 2031endif # X86_32 2032 2033config K8_NB 2034 def_bool y 2035 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA))) 2036 2037source "drivers/pcmcia/Kconfig" 2038 2039source "drivers/pci/hotplug/Kconfig" 2040 2041endmenu 2042 2043 2044menu "Executable file formats / Emulations" 2045 2046source "fs/Kconfig.binfmt" 2047 2048config 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 2057config 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 2063config COMPAT 2064 def_bool y 2065 depends on IA32_EMULATION 2066 2067config COMPAT_FOR_U64_ALIGNMENT 2068 def_bool COMPAT 2069 depends on X86_64 2070 2071config SYSVIPC_COMPAT 2072 def_bool y 2073 depends on COMPAT && SYSVIPC 2074 2075endmenu 2076 2077 2078config HAVE_ATOMIC_IOMAP 2079 def_bool y 2080 depends on X86_32 2081 2082source "net/Kconfig" 2083 2084source "drivers/Kconfig" 2085 2086source "drivers/firmware/Kconfig" 2087 2088source "fs/Kconfig" 2089 2090source "arch/x86/Kconfig.debug" 2091 2092source "security/Kconfig" 2093 2094source "crypto/Kconfig" 2095 2096source "arch/x86/kvm/Kconfig" 2097 2098source "lib/Kconfig" 2099