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_DMA_ATTRS 32 select HAVE_KRETPROBES 33 select HAVE_FTRACE_MCOUNT_RECORD 34 select HAVE_DYNAMIC_FTRACE 35 select HAVE_FUNCTION_TRACER 36 select HAVE_FUNCTION_GRAPH_TRACER 37 select HAVE_FUNCTION_GRAPH_FP_TEST 38 select HAVE_FUNCTION_TRACE_MCOUNT_TEST 39 select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE 40 select HAVE_FTRACE_SYSCALLS 41 select HAVE_KVM 42 select HAVE_ARCH_KGDB 43 select HAVE_ARCH_TRACEHOOK 44 select HAVE_GENERIC_DMA_COHERENT if X86_32 45 select HAVE_EFFICIENT_UNALIGNED_ACCESS 46 select USER_STACKTRACE_SUPPORT 47 select HAVE_DMA_API_DEBUG 48 select HAVE_KERNEL_GZIP 49 select HAVE_KERNEL_BZIP2 50 select HAVE_KERNEL_LZMA 51 select HAVE_ARCH_KMEMCHECK 52 53config OUTPUT_FORMAT 54 string 55 default "elf32-i386" if X86_32 56 default "elf64-x86-64" if X86_64 57 58config ARCH_DEFCONFIG 59 string 60 default "arch/x86/configs/i386_defconfig" if X86_32 61 default "arch/x86/configs/x86_64_defconfig" if X86_64 62 63config GENERIC_TIME 64 def_bool y 65 66config GENERIC_CMOS_UPDATE 67 def_bool y 68 69config CLOCKSOURCE_WATCHDOG 70 def_bool y 71 72config GENERIC_CLOCKEVENTS 73 def_bool y 74 75config GENERIC_CLOCKEVENTS_BROADCAST 76 def_bool y 77 depends on X86_64 || (X86_32 && X86_LOCAL_APIC) 78 79config LOCKDEP_SUPPORT 80 def_bool y 81 82config STACKTRACE_SUPPORT 83 def_bool y 84 85config HAVE_LATENCYTOP_SUPPORT 86 def_bool y 87 88config FAST_CMPXCHG_LOCAL 89 bool 90 default y 91 92config MMU 93 def_bool y 94 95config ZONE_DMA 96 def_bool y 97 98config SBUS 99 bool 100 101config GENERIC_ISA_DMA 102 def_bool y 103 104config GENERIC_IOMAP 105 def_bool y 106 107config GENERIC_BUG 108 def_bool y 109 depends on BUG 110 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 111 112config GENERIC_BUG_RELATIVE_POINTERS 113 bool 114 115config GENERIC_HWEIGHT 116 def_bool y 117 118config GENERIC_GPIO 119 bool 120 121config ARCH_MAY_HAVE_PC_FDC 122 def_bool y 123 124config RWSEM_GENERIC_SPINLOCK 125 def_bool !X86_XADD 126 127config RWSEM_XCHGADD_ALGORITHM 128 def_bool X86_XADD 129 130config ARCH_HAS_CPU_IDLE_WAIT 131 def_bool y 132 133config GENERIC_CALIBRATE_DELAY 134 def_bool y 135 136config GENERIC_TIME_VSYSCALL 137 bool 138 default X86_64 139 140config ARCH_HAS_CPU_RELAX 141 def_bool y 142 143config ARCH_HAS_DEFAULT_IDLE 144 def_bool y 145 146config ARCH_HAS_CACHE_LINE_SIZE 147 def_bool y 148 149config HAVE_SETUP_PER_CPU_AREA 150 def_bool y 151 152config HAVE_DYNAMIC_PER_CPU_AREA 153 def_bool y 154 155config HAVE_CPUMASK_OF_CPU_MAP 156 def_bool X86_64_SMP 157 158config ARCH_HIBERNATION_POSSIBLE 159 def_bool y 160 161config ARCH_SUSPEND_POSSIBLE 162 def_bool y 163 164config ZONE_DMA32 165 bool 166 default X86_64 167 168config ARCH_POPULATES_NODE_MAP 169 def_bool y 170 171config AUDIT_ARCH 172 bool 173 default X86_64 174 175config ARCH_SUPPORTS_OPTIMIZED_INLINING 176 def_bool y 177 178config ARCH_SUPPORTS_DEBUG_PAGEALLOC 179 def_bool y 180 181# Use the generic interrupt handling code in kernel/irq/: 182config GENERIC_HARDIRQS 183 bool 184 default y 185 186config GENERIC_HARDIRQS_NO__DO_IRQ 187 def_bool y 188 189config GENERIC_IRQ_PROBE 190 bool 191 default y 192 193config GENERIC_PENDING_IRQ 194 bool 195 depends on GENERIC_HARDIRQS && SMP 196 default y 197 198config USE_GENERIC_SMP_HELPERS 199 def_bool y 200 depends on SMP 201 202config X86_32_SMP 203 def_bool y 204 depends on X86_32 && SMP 205 206config X86_64_SMP 207 def_bool y 208 depends on X86_64 && SMP 209 210config X86_HT 211 bool 212 depends on SMP 213 default y 214 215config X86_TRAMPOLINE 216 bool 217 depends on SMP || (64BIT && ACPI_SLEEP) 218 default y 219 220config X86_32_LAZY_GS 221 def_bool y 222 depends on X86_32 && !CC_STACKPROTECTOR 223 224config KTIME_SCALAR 225 def_bool X86_32 226source "init/Kconfig" 227source "kernel/Kconfig.freezer" 228 229menu "Processor type and features" 230 231source "kernel/time/Kconfig" 232 233config SMP 234 bool "Symmetric multi-processing support" 235 ---help--- 236 This enables support for systems with more than one CPU. If you have 237 a system with only one CPU, like most personal computers, say N. If 238 you have a system with more than one CPU, say Y. 239 240 If you say N here, the kernel will run on single and multiprocessor 241 machines, but will use only one CPU of a multiprocessor machine. If 242 you say Y here, the kernel will run on many, but not all, 243 singleprocessor machines. On a singleprocessor machine, the kernel 244 will run faster if you say N here. 245 246 Note that if you say Y here and choose architecture "586" or 247 "Pentium" under "Processor family", the kernel will not work on 486 248 architectures. Similarly, multiprocessor kernels for the "PPro" 249 architecture may not work on all Pentium based boards. 250 251 People using multiprocessor machines who say Y here should also say 252 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 253 Management" code will be disabled if you say Y here. 254 255 See also <file:Documentation/i386/IO-APIC.txt>, 256 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 257 <http://www.tldp.org/docs.html#howto>. 258 259 If you don't know what to do here, say N. 260 261config X86_X2APIC 262 bool "Support x2apic" 263 depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP 264 ---help--- 265 This enables x2apic support on CPUs that have this feature. 266 267 This allows 32-bit apic IDs (so it can support very large systems), 268 and accesses the local apic via MSRs not via mmio. 269 270 If you don't know what to do here, say N. 271 272config SPARSE_IRQ 273 bool "Support sparse irq numbering" 274 depends on PCI_MSI || HT_IRQ 275 ---help--- 276 This enables support for sparse irqs. This is useful for distro 277 kernels that want to define a high CONFIG_NR_CPUS value but still 278 want to have low kernel memory footprint on smaller machines. 279 280 ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread 281 out the irq_desc[] array in a more NUMA-friendly way. ) 282 283 If you don't know what to do here, say N. 284 285config NUMA_IRQ_DESC 286 def_bool y 287 depends on SPARSE_IRQ && NUMA 288 289config X86_MPPARSE 290 bool "Enable MPS table" if ACPI 291 default y 292 depends on X86_LOCAL_APIC 293 ---help--- 294 For old smp systems that do not have proper acpi support. Newer systems 295 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 296 297config X86_BIGSMP 298 bool "Support for big SMP systems with more than 8 CPUs" 299 depends on X86_32 && SMP 300 ---help--- 301 This option is needed for the systems that have more than 8 CPUs 302 303if X86_32 304config X86_EXTENDED_PLATFORM 305 bool "Support for extended (non-PC) x86 platforms" 306 default y 307 ---help--- 308 If you disable this option then the kernel will only support 309 standard PC platforms. (which covers the vast majority of 310 systems out there.) 311 312 If you enable this option then you'll be able to select support 313 for the following (non-PC) 32 bit x86 platforms: 314 AMD Elan 315 NUMAQ (IBM/Sequent) 316 RDC R-321x SoC 317 SGI 320/540 (Visual Workstation) 318 Summit/EXA (IBM x440) 319 Unisys ES7000 IA32 series 320 321 If you have one of these systems, or if you want to build a 322 generic distribution kernel, say Y here - otherwise say N. 323endif 324 325if X86_64 326config X86_EXTENDED_PLATFORM 327 bool "Support for extended (non-PC) x86 platforms" 328 default y 329 ---help--- 330 If you disable this option then the kernel will only support 331 standard PC platforms. (which covers the vast majority of 332 systems out there.) 333 334 If you enable this option then you'll be able to select support 335 for the following (non-PC) 64 bit x86 platforms: 336 ScaleMP vSMP 337 SGI Ultraviolet 338 339 If you have one of these systems, or if you want to build a 340 generic distribution kernel, say Y here - otherwise say N. 341endif 342# This is an alphabetically sorted list of 64 bit extended platforms 343# Please maintain the alphabetic order if and when there are additions 344 345config X86_VSMP 346 bool "ScaleMP vSMP" 347 select PARAVIRT 348 depends on X86_64 && PCI 349 depends on X86_EXTENDED_PLATFORM 350 ---help--- 351 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 352 supposed to run on these EM64T-based machines. Only choose this option 353 if you have one of these machines. 354 355config X86_UV 356 bool "SGI Ultraviolet" 357 depends on X86_64 358 depends on X86_EXTENDED_PLATFORM 359 depends on NUMA 360 depends on X86_X2APIC 361 ---help--- 362 This option is needed in order to support SGI Ultraviolet systems. 363 If you don't have one of these, you should say N here. 364 365# Following is an alphabetically sorted list of 32 bit extended platforms 366# Please maintain the alphabetic order if and when there are additions 367 368config X86_ELAN 369 bool "AMD Elan" 370 depends on X86_32 371 depends on X86_EXTENDED_PLATFORM 372 ---help--- 373 Select this for an AMD Elan processor. 374 375 Do not use this option for K6/Athlon/Opteron processors! 376 377 If unsure, choose "PC-compatible" instead. 378 379config X86_RDC321X 380 bool "RDC R-321x SoC" 381 depends on X86_32 382 depends on X86_EXTENDED_PLATFORM 383 select M486 384 select X86_REBOOTFIXUPS 385 ---help--- 386 This option is needed for RDC R-321x system-on-chip, also known 387 as R-8610-(G). 388 If you don't have one of these chips, you should say N here. 389 390config X86_32_NON_STANDARD 391 bool "Support non-standard 32-bit SMP architectures" 392 depends on X86_32 && SMP 393 depends on X86_EXTENDED_PLATFORM 394 ---help--- 395 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default 396 subarchitectures. It is intended for a generic binary kernel. 397 if you select them all, kernel will probe it one by one. and will 398 fallback to default. 399 400# Alphabetically sorted list of Non standard 32 bit platforms 401 402config X86_NUMAQ 403 bool "NUMAQ (IBM/Sequent)" 404 depends on X86_32_NON_STANDARD 405 select NUMA 406 select X86_MPPARSE 407 ---help--- 408 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent) 409 NUMA multiquad box. This changes the way that processors are 410 bootstrapped, and uses Clustered Logical APIC addressing mode instead 411 of Flat Logical. You will need a new lynxer.elf file to flash your 412 firmware with - send email to <Martin.Bligh@us.ibm.com>. 413 414config X86_VISWS 415 bool "SGI 320/540 (Visual Workstation)" 416 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT 417 depends on X86_32_NON_STANDARD 418 ---help--- 419 The SGI Visual Workstation series is an IA32-based workstation 420 based on SGI systems chips with some legacy PC hardware attached. 421 422 Say Y here to create a kernel to run on the SGI 320 or 540. 423 424 A kernel compiled for the Visual Workstation will run on general 425 PCs as well. See <file:Documentation/sgi-visws.txt> for details. 426 427config X86_SUMMIT 428 bool "Summit/EXA (IBM x440)" 429 depends on X86_32_NON_STANDARD 430 ---help--- 431 This option is needed for IBM systems that use the Summit/EXA chipset. 432 In particular, it is needed for the x440. 433 434config X86_ES7000 435 bool "Unisys ES7000 IA32 series" 436 depends on X86_32_NON_STANDARD && X86_BIGSMP 437 ---help--- 438 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is 439 supposed to run on an IA32-based Unisys ES7000 system. 440 441config SCHED_OMIT_FRAME_POINTER 442 def_bool y 443 prompt "Single-depth WCHAN output" 444 depends on X86 445 ---help--- 446 Calculate simpler /proc/<PID>/wchan values. If this option 447 is disabled then wchan values will recurse back to the 448 caller function. This provides more accurate wchan values, 449 at the expense of slightly more scheduling overhead. 450 451 If in doubt, say "Y". 452 453menuconfig PARAVIRT_GUEST 454 bool "Paravirtualized guest support" 455 ---help--- 456 Say Y here to get to see options related to running Linux under 457 various hypervisors. This option alone does not add any kernel code. 458 459 If you say N, all options in this submenu will be skipped and disabled. 460 461if PARAVIRT_GUEST 462 463source "arch/x86/xen/Kconfig" 464 465config VMI 466 bool "VMI Guest support" 467 select PARAVIRT 468 depends on X86_32 469 ---help--- 470 VMI provides a paravirtualized interface to the VMware ESX server 471 (it could be used by other hypervisors in theory too, but is not 472 at the moment), by linking the kernel to a GPL-ed ROM module 473 provided by the hypervisor. 474 475config KVM_CLOCK 476 bool "KVM paravirtualized clock" 477 select PARAVIRT 478 select PARAVIRT_CLOCK 479 ---help--- 480 Turning on this option will allow you to run a paravirtualized clock 481 when running over the KVM hypervisor. Instead of relying on a PIT 482 (or probably other) emulation by the underlying device model, the host 483 provides the guest with timing infrastructure such as time of day, and 484 system time 485 486config KVM_GUEST 487 bool "KVM Guest support" 488 select PARAVIRT 489 ---help--- 490 This option enables various optimizations for running under the KVM 491 hypervisor. 492 493source "arch/x86/lguest/Kconfig" 494 495config PARAVIRT 496 bool "Enable paravirtualization code" 497 ---help--- 498 This changes the kernel so it can modify itself when it is run 499 under a hypervisor, potentially improving performance significantly 500 over full virtualization. However, when run without a hypervisor 501 the kernel is theoretically slower and slightly larger. 502 503config PARAVIRT_SPINLOCKS 504 bool "Paravirtualization layer for spinlocks" 505 depends on PARAVIRT && SMP && EXPERIMENTAL 506 ---help--- 507 Paravirtualized spinlocks allow a pvops backend to replace the 508 spinlock implementation with something virtualization-friendly 509 (for example, block the virtual CPU rather than spinning). 510 511 Unfortunately the downside is an up to 5% performance hit on 512 native kernels, with various workloads. 513 514 If you are unsure how to answer this question, answer N. 515 516config PARAVIRT_CLOCK 517 bool 518 default n 519 520endif 521 522config PARAVIRT_DEBUG 523 bool "paravirt-ops debugging" 524 depends on PARAVIRT && DEBUG_KERNEL 525 ---help--- 526 Enable to debug paravirt_ops internals. Specifically, BUG if 527 a paravirt_op is missing when it is called. 528 529config MEMTEST 530 bool "Memtest" 531 ---help--- 532 This option adds a kernel parameter 'memtest', which allows memtest 533 to be set. 534 memtest=0, mean disabled; -- default 535 memtest=1, mean do 1 test pattern; 536 ... 537 memtest=4, mean do 4 test patterns. 538 If you are unsure how to answer this question, answer N. 539 540config X86_SUMMIT_NUMA 541 def_bool y 542 depends on X86_32 && NUMA && X86_32_NON_STANDARD 543 544config X86_CYCLONE_TIMER 545 def_bool y 546 depends on X86_32_NON_STANDARD 547 548source "arch/x86/Kconfig.cpu" 549 550config HPET_TIMER 551 def_bool X86_64 552 prompt "HPET Timer Support" if X86_32 553 ---help--- 554 Use the IA-PC HPET (High Precision Event Timer) to manage 555 time in preference to the PIT and RTC, if a HPET is 556 present. 557 HPET is the next generation timer replacing legacy 8254s. 558 The HPET provides a stable time base on SMP 559 systems, unlike the TSC, but it is more expensive to access, 560 as it is off-chip. You can find the HPET spec at 561 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>. 562 563 You can safely choose Y here. However, HPET will only be 564 activated if the platform and the BIOS support this feature. 565 Otherwise the 8254 will be used for timing services. 566 567 Choose N to continue using the legacy 8254 timer. 568 569config HPET_EMULATE_RTC 570 def_bool y 571 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 572 573# Mark as embedded because too many people got it wrong. 574# The code disables itself when not needed. 575config DMI 576 default y 577 bool "Enable DMI scanning" if EMBEDDED 578 ---help--- 579 Enabled scanning of DMI to identify machine quirks. Say Y 580 here unless you have verified that your setup is not 581 affected by entries in the DMI blacklist. Required by PNP 582 BIOS code. 583 584config GART_IOMMU 585 bool "GART IOMMU support" if EMBEDDED 586 default y 587 select SWIOTLB 588 select AGP 589 depends on X86_64 && PCI 590 ---help--- 591 Support for full DMA access of devices with 32bit memory access only 592 on systems with more than 3GB. This is usually needed for USB, 593 sound, many IDE/SATA chipsets and some other devices. 594 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART 595 based hardware IOMMU and a software bounce buffer based IOMMU used 596 on Intel systems and as fallback. 597 The code is only active when needed (enough memory and limited 598 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified 599 too. 600 601config CALGARY_IOMMU 602 bool "IBM Calgary IOMMU support" 603 select SWIOTLB 604 depends on X86_64 && PCI && EXPERIMENTAL 605 ---help--- 606 Support for hardware IOMMUs in IBM's xSeries x366 and x460 607 systems. Needed to run systems with more than 3GB of memory 608 properly with 32-bit PCI devices that do not support DAC 609 (Double Address Cycle). Calgary also supports bus level 610 isolation, where all DMAs pass through the IOMMU. This 611 prevents them from going anywhere except their intended 612 destination. This catches hard-to-find kernel bugs and 613 mis-behaving drivers and devices that do not use the DMA-API 614 properly to set up their DMA buffers. The IOMMU can be 615 turned off at boot time with the iommu=off parameter. 616 Normally the kernel will make the right choice by itself. 617 If unsure, say Y. 618 619config CALGARY_IOMMU_ENABLED_BY_DEFAULT 620 def_bool y 621 prompt "Should Calgary be enabled by default?" 622 depends on CALGARY_IOMMU 623 ---help--- 624 Should Calgary be enabled by default? if you choose 'y', Calgary 625 will be used (if it exists). If you choose 'n', Calgary will not be 626 used even if it exists. If you choose 'n' and would like to use 627 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 628 If unsure, say Y. 629 630config AMD_IOMMU 631 bool "AMD IOMMU support" 632 select SWIOTLB 633 select PCI_MSI 634 depends on X86_64 && PCI && ACPI 635 ---help--- 636 With this option you can enable support for AMD IOMMU hardware in 637 your system. An IOMMU is a hardware component which provides 638 remapping of DMA memory accesses from devices. With an AMD IOMMU you 639 can isolate the the DMA memory of different devices and protect the 640 system from misbehaving device drivers or hardware. 641 642 You can find out if your system has an AMD IOMMU if you look into 643 your BIOS for an option to enable it or if you have an IVRS ACPI 644 table. 645 646config AMD_IOMMU_STATS 647 bool "Export AMD IOMMU statistics to debugfs" 648 depends on AMD_IOMMU 649 select DEBUG_FS 650 ---help--- 651 This option enables code in the AMD IOMMU driver to collect various 652 statistics about whats happening in the driver and exports that 653 information to userspace via debugfs. 654 If unsure, say N. 655 656# need this always selected by IOMMU for the VIA workaround 657config SWIOTLB 658 def_bool y if X86_64 659 ---help--- 660 Support for software bounce buffers used on x86-64 systems 661 which don't have a hardware IOMMU (e.g. the current generation 662 of Intel's x86-64 CPUs). Using this PCI devices which can only 663 access 32-bits of memory can be used on systems with more than 664 3 GB of memory. If unsure, say Y. 665 666config IOMMU_HELPER 667 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU) 668 669config IOMMU_API 670 def_bool (AMD_IOMMU || DMAR) 671 672config MAXSMP 673 bool "Configure Maximum number of SMP Processors and NUMA Nodes" 674 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL 675 select CPUMASK_OFFSTACK 676 default n 677 ---help--- 678 Configure maximum number of CPUS and NUMA Nodes for this architecture. 679 If unsure, say N. 680 681config NR_CPUS 682 int "Maximum number of CPUs" if SMP && !MAXSMP 683 range 2 8 if SMP && X86_32 && !X86_BIGSMP 684 range 2 512 if SMP && !MAXSMP 685 default "1" if !SMP 686 default "4096" if MAXSMP 687 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000) 688 default "8" if SMP 689 ---help--- 690 This allows you to specify the maximum number of CPUs which this 691 kernel will support. The maximum supported value is 512 and the 692 minimum value which makes sense is 2. 693 694 This is purely to save memory - each supported CPU adds 695 approximately eight kilobytes to the kernel image. 696 697config SCHED_SMT 698 bool "SMT (Hyperthreading) scheduler support" 699 depends on X86_HT 700 ---help--- 701 SMT scheduler support improves the CPU scheduler's decision making 702 when dealing with Intel Pentium 4 chips with HyperThreading at a 703 cost of slightly increased overhead in some places. If unsure say 704 N here. 705 706config SCHED_MC 707 def_bool y 708 prompt "Multi-core scheduler support" 709 depends on X86_HT 710 ---help--- 711 Multi-core scheduler support improves the CPU scheduler's decision 712 making when dealing with multi-core CPU chips at a cost of slightly 713 increased overhead in some places. If unsure say N here. 714 715source "kernel/Kconfig.preempt" 716 717config X86_UP_APIC 718 bool "Local APIC support on uniprocessors" 719 depends on X86_32 && !SMP && !X86_32_NON_STANDARD 720 ---help--- 721 A local APIC (Advanced Programmable Interrupt Controller) is an 722 integrated interrupt controller in the CPU. If you have a single-CPU 723 system which has a processor with a local APIC, you can say Y here to 724 enable and use it. If you say Y here even though your machine doesn't 725 have a local APIC, then the kernel will still run with no slowdown at 726 all. The local APIC supports CPU-generated self-interrupts (timer, 727 performance counters), and the NMI watchdog which detects hard 728 lockups. 729 730config X86_UP_IOAPIC 731 bool "IO-APIC support on uniprocessors" 732 depends on X86_UP_APIC 733 ---help--- 734 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 735 SMP-capable replacement for PC-style interrupt controllers. Most 736 SMP systems and many recent uniprocessor systems have one. 737 738 If you have a single-CPU system with an IO-APIC, you can say Y here 739 to use it. If you say Y here even though your machine doesn't have 740 an IO-APIC, then the kernel will still run with no slowdown at all. 741 742config X86_LOCAL_APIC 743 def_bool y 744 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC 745 select HAVE_PERF_COUNTERS if (!M386 && !M486) 746 747config X86_IO_APIC 748 def_bool y 749 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC 750 751config X86_VISWS_APIC 752 def_bool y 753 depends on X86_32 && X86_VISWS 754 755config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 756 bool "Reroute for broken boot IRQs" 757 default n 758 depends on X86_IO_APIC 759 ---help--- 760 This option enables a workaround that fixes a source of 761 spurious interrupts. This is recommended when threaded 762 interrupt handling is used on systems where the generation of 763 superfluous "boot interrupts" cannot be disabled. 764 765 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 766 entry in the chipset's IO-APIC is masked (as, e.g. the RT 767 kernel does during interrupt handling). On chipsets where this 768 boot IRQ generation cannot be disabled, this workaround keeps 769 the original IRQ line masked so that only the equivalent "boot 770 IRQ" is delivered to the CPUs. The workaround also tells the 771 kernel to set up the IRQ handler on the boot IRQ line. In this 772 way only one interrupt is delivered to the kernel. Otherwise 773 the spurious second interrupt may cause the kernel to bring 774 down (vital) interrupt lines. 775 776 Only affects "broken" chipsets. Interrupt sharing may be 777 increased on these systems. 778 779config X86_MCE 780 bool "Machine Check Exception" 781 ---help--- 782 Machine Check Exception support allows the processor to notify the 783 kernel if it detects a problem (e.g. overheating, component failure). 784 The action the kernel takes depends on the severity of the problem, 785 ranging from a warning message on the console, to halting the machine. 786 Your processor must be a Pentium or newer to support this - check the 787 flags in /proc/cpuinfo for mce. Note that some older Pentium systems 788 have a design flaw which leads to false MCE events - hence MCE is 789 disabled on all P5 processors, unless explicitly enabled with "mce" 790 as a boot argument. Similarly, if MCE is built in and creates a 791 problem on some new non-standard machine, you can boot with "nomce" 792 to disable it. MCE support simply ignores non-MCE processors like 793 the 386 and 486, so nearly everyone can say Y here. 794 795config X86_OLD_MCE 796 depends on X86_32 && X86_MCE 797 bool "Use legacy machine check code (will go away)" 798 default n 799 select X86_ANCIENT_MCE 800 ---help--- 801 Use the old i386 machine check code. This is merely intended for 802 testing in a transition period. Try this if you run into any machine 803 check related software problems, but report the problem to 804 linux-kernel. When in doubt say no. 805 806config X86_NEW_MCE 807 depends on X86_MCE 808 bool 809 default y if (!X86_OLD_MCE && X86_32) || X86_64 810 811config X86_MCE_INTEL 812 def_bool y 813 prompt "Intel MCE features" 814 depends on X86_NEW_MCE && X86_LOCAL_APIC 815 ---help--- 816 Additional support for intel specific MCE features such as 817 the thermal monitor. 818 819config X86_MCE_AMD 820 def_bool y 821 prompt "AMD MCE features" 822 depends on X86_NEW_MCE && X86_LOCAL_APIC 823 ---help--- 824 Additional support for AMD specific MCE features such as 825 the DRAM Error Threshold. 826 827config X86_ANCIENT_MCE 828 def_bool n 829 depends on X86_32 830 prompt "Support for old Pentium 5 / WinChip machine checks" 831 ---help--- 832 Include support for machine check handling on old Pentium 5 or WinChip 833 systems. These typically need to be enabled explicitely on the command 834 line. 835 836config X86_MCE_THRESHOLD 837 depends on X86_MCE_AMD || X86_MCE_INTEL 838 bool 839 default y 840 841config X86_MCE_INJECT 842 depends on X86_NEW_MCE 843 tristate "Machine check injector support" 844 ---help--- 845 Provide support for injecting machine checks for testing purposes. 846 If you don't know what a machine check is and you don't do kernel 847 QA it is safe to say n. 848 849config X86_MCE_NONFATAL 850 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4" 851 depends on X86_OLD_MCE 852 ---help--- 853 Enabling this feature starts a timer that triggers every 5 seconds which 854 will look at the machine check registers to see if anything happened. 855 Non-fatal problems automatically get corrected (but still logged). 856 Disable this if you don't want to see these messages. 857 Seeing the messages this option prints out may be indicative of dying 858 or out-of-spec (ie, overclocked) hardware. 859 This option only does something on certain CPUs. 860 (AMD Athlon/Duron and Intel Pentium 4) 861 862config X86_MCE_P4THERMAL 863 bool "check for P4 thermal throttling interrupt." 864 depends on X86_OLD_MCE && X86_MCE && (X86_UP_APIC || SMP) 865 ---help--- 866 Enabling this feature will cause a message to be printed when the P4 867 enters thermal throttling. 868 869config X86_THERMAL_VECTOR 870 def_bool y 871 depends on X86_MCE_P4THERMAL || X86_MCE_INTEL 872 873config VM86 874 bool "Enable VM86 support" if EMBEDDED 875 default y 876 depends on X86_32 877 ---help--- 878 This option is required by programs like DOSEMU to run 16-bit legacy 879 code on X86 processors. It also may be needed by software like 880 XFree86 to initialize some video cards via BIOS. Disabling this 881 option saves about 6k. 882 883config TOSHIBA 884 tristate "Toshiba Laptop support" 885 depends on X86_32 886 ---help--- 887 This adds a driver to safely access the System Management Mode of 888 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 889 not work on models with a Phoenix BIOS. The System Management Mode 890 is used to set the BIOS and power saving options on Toshiba portables. 891 892 For information on utilities to make use of this driver see the 893 Toshiba Linux utilities web site at: 894 <http://www.buzzard.org.uk/toshiba/>. 895 896 Say Y if you intend to run this kernel on a Toshiba portable. 897 Say N otherwise. 898 899config I8K 900 tristate "Dell laptop support" 901 ---help--- 902 This adds a driver to safely access the System Management Mode 903 of the CPU on the Dell Inspiron 8000. The System Management Mode 904 is used to read cpu temperature and cooling fan status and to 905 control the fans on the I8K portables. 906 907 This driver has been tested only on the Inspiron 8000 but it may 908 also work with other Dell laptops. You can force loading on other 909 models by passing the parameter `force=1' to the module. Use at 910 your own risk. 911 912 For information on utilities to make use of this driver see the 913 I8K Linux utilities web site at: 914 <http://people.debian.org/~dz/i8k/> 915 916 Say Y if you intend to run this kernel on a Dell Inspiron 8000. 917 Say N otherwise. 918 919config X86_REBOOTFIXUPS 920 bool "Enable X86 board specific fixups for reboot" 921 depends on X86_32 922 ---help--- 923 This enables chipset and/or board specific fixups to be done 924 in order to get reboot to work correctly. This is only needed on 925 some combinations of hardware and BIOS. The symptom, for which 926 this config is intended, is when reboot ends with a stalled/hung 927 system. 928 929 Currently, the only fixup is for the Geode machines using 930 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 931 932 Say Y if you want to enable the fixup. Currently, it's safe to 933 enable this option even if you don't need it. 934 Say N otherwise. 935 936config MICROCODE 937 tristate "/dev/cpu/microcode - microcode support" 938 select FW_LOADER 939 ---help--- 940 If you say Y here, you will be able to update the microcode on 941 certain Intel and AMD processors. The Intel support is for the 942 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, 943 Pentium 4, Xeon etc. The AMD support is for family 0x10 and 944 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra. 945 You will obviously need the actual microcode binary data itself 946 which is not shipped with the Linux kernel. 947 948 This option selects the general module only, you need to select 949 at least one vendor specific module as well. 950 951 To compile this driver as a module, choose M here: the 952 module will be called microcode. 953 954config MICROCODE_INTEL 955 bool "Intel microcode patch loading support" 956 depends on MICROCODE 957 default MICROCODE 958 select FW_LOADER 959 ---help--- 960 This options enables microcode patch loading support for Intel 961 processors. 962 963 For latest news and information on obtaining all the required 964 Intel ingredients for this driver, check: 965 <http://www.urbanmyth.org/microcode/>. 966 967config MICROCODE_AMD 968 bool "AMD microcode patch loading support" 969 depends on MICROCODE 970 select FW_LOADER 971 ---help--- 972 If you select this option, microcode patch loading support for AMD 973 processors will be enabled. 974 975config MICROCODE_OLD_INTERFACE 976 def_bool y 977 depends on MICROCODE 978 979config X86_MSR 980 tristate "/dev/cpu/*/msr - Model-specific register support" 981 ---help--- 982 This device gives privileged processes access to the x86 983 Model-Specific Registers (MSRs). It is a character device with 984 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 985 MSR accesses are directed to a specific CPU on multi-processor 986 systems. 987 988config X86_CPUID 989 tristate "/dev/cpu/*/cpuid - CPU information support" 990 ---help--- 991 This device gives processes access to the x86 CPUID instruction to 992 be executed on a specific processor. It is a character device 993 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 994 /dev/cpu/31/cpuid. 995 996config X86_CPU_DEBUG 997 tristate "/sys/kernel/debug/x86/cpu/* - CPU Debug support" 998 ---help--- 999 If you select this option, this will provide various x86 CPUs 1000 information through debugfs. 1001 1002choice 1003 prompt "High Memory Support" 1004 default HIGHMEM4G if !X86_NUMAQ 1005 default HIGHMEM64G if X86_NUMAQ 1006 depends on X86_32 1007 1008config NOHIGHMEM 1009 bool "off" 1010 depends on !X86_NUMAQ 1011 ---help--- 1012 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1013 However, the address space of 32-bit x86 processors is only 4 1014 Gigabytes large. That means that, if you have a large amount of 1015 physical memory, not all of it can be "permanently mapped" by the 1016 kernel. The physical memory that's not permanently mapped is called 1017 "high memory". 1018 1019 If you are compiling a kernel which will never run on a machine with 1020 more than 1 Gigabyte total physical RAM, answer "off" here (default 1021 choice and suitable for most users). This will result in a "3GB/1GB" 1022 split: 3GB are mapped so that each process sees a 3GB virtual memory 1023 space and the remaining part of the 4GB virtual memory space is used 1024 by the kernel to permanently map as much physical memory as 1025 possible. 1026 1027 If the machine has between 1 and 4 Gigabytes physical RAM, then 1028 answer "4GB" here. 1029 1030 If more than 4 Gigabytes is used then answer "64GB" here. This 1031 selection turns Intel PAE (Physical Address Extension) mode on. 1032 PAE implements 3-level paging on IA32 processors. PAE is fully 1033 supported by Linux, PAE mode is implemented on all recent Intel 1034 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1035 then the kernel will not boot on CPUs that don't support PAE! 1036 1037 The actual amount of total physical memory will either be 1038 auto detected or can be forced by using a kernel command line option 1039 such as "mem=256M". (Try "man bootparam" or see the documentation of 1040 your boot loader (lilo or loadlin) about how to pass options to the 1041 kernel at boot time.) 1042 1043 If unsure, say "off". 1044 1045config HIGHMEM4G 1046 bool "4GB" 1047 depends on !X86_NUMAQ 1048 ---help--- 1049 Select this if you have a 32-bit processor and between 1 and 4 1050 gigabytes of physical RAM. 1051 1052config HIGHMEM64G 1053 bool "64GB" 1054 depends on !M386 && !M486 1055 select X86_PAE 1056 ---help--- 1057 Select this if you have a 32-bit processor and more than 4 1058 gigabytes of physical RAM. 1059 1060endchoice 1061 1062choice 1063 depends on EXPERIMENTAL 1064 prompt "Memory split" if EMBEDDED 1065 default VMSPLIT_3G 1066 depends on X86_32 1067 ---help--- 1068 Select the desired split between kernel and user memory. 1069 1070 If the address range available to the kernel is less than the 1071 physical memory installed, the remaining memory will be available 1072 as "high memory". Accessing high memory is a little more costly 1073 than low memory, as it needs to be mapped into the kernel first. 1074 Note that increasing the kernel address space limits the range 1075 available to user programs, making the address space there 1076 tighter. Selecting anything other than the default 3G/1G split 1077 will also likely make your kernel incompatible with binary-only 1078 kernel modules. 1079 1080 If you are not absolutely sure what you are doing, leave this 1081 option alone! 1082 1083 config VMSPLIT_3G 1084 bool "3G/1G user/kernel split" 1085 config VMSPLIT_3G_OPT 1086 depends on !X86_PAE 1087 bool "3G/1G user/kernel split (for full 1G low memory)" 1088 config VMSPLIT_2G 1089 bool "2G/2G user/kernel split" 1090 config VMSPLIT_2G_OPT 1091 depends on !X86_PAE 1092 bool "2G/2G user/kernel split (for full 2G low memory)" 1093 config VMSPLIT_1G 1094 bool "1G/3G user/kernel split" 1095endchoice 1096 1097config PAGE_OFFSET 1098 hex 1099 default 0xB0000000 if VMSPLIT_3G_OPT 1100 default 0x80000000 if VMSPLIT_2G 1101 default 0x78000000 if VMSPLIT_2G_OPT 1102 default 0x40000000 if VMSPLIT_1G 1103 default 0xC0000000 1104 depends on X86_32 1105 1106config HIGHMEM 1107 def_bool y 1108 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1109 1110config X86_PAE 1111 bool "PAE (Physical Address Extension) Support" 1112 depends on X86_32 && !HIGHMEM4G 1113 ---help--- 1114 PAE is required for NX support, and furthermore enables 1115 larger swapspace support for non-overcommit purposes. It 1116 has the cost of more pagetable lookup overhead, and also 1117 consumes more pagetable space per process. 1118 1119config ARCH_PHYS_ADDR_T_64BIT 1120 def_bool X86_64 || X86_PAE 1121 1122config DIRECT_GBPAGES 1123 bool "Enable 1GB pages for kernel pagetables" if EMBEDDED 1124 default y 1125 depends on X86_64 1126 ---help--- 1127 Allow the kernel linear mapping to use 1GB pages on CPUs that 1128 support it. This can improve the kernel's performance a tiny bit by 1129 reducing TLB pressure. If in doubt, say "Y". 1130 1131# Common NUMA Features 1132config NUMA 1133 bool "Numa Memory Allocation and Scheduler Support" 1134 depends on SMP 1135 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL) 1136 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP) 1137 ---help--- 1138 Enable NUMA (Non Uniform Memory Access) support. 1139 1140 The kernel will try to allocate memory used by a CPU on the 1141 local memory controller of the CPU and add some more 1142 NUMA awareness to the kernel. 1143 1144 For 64-bit this is recommended if the system is Intel Core i7 1145 (or later), AMD Opteron, or EM64T NUMA. 1146 1147 For 32-bit this is only needed on (rare) 32-bit-only platforms 1148 that support NUMA topologies, such as NUMAQ / Summit, or if you 1149 boot a 32-bit kernel on a 64-bit NUMA platform. 1150 1151 Otherwise, you should say N. 1152 1153comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI" 1154 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI) 1155 1156config K8_NUMA 1157 def_bool y 1158 prompt "Old style AMD Opteron NUMA detection" 1159 depends on X86_64 && NUMA && PCI 1160 ---help--- 1161 Enable K8 NUMA node topology detection. You should say Y here if 1162 you have a multi processor AMD K8 system. This uses an old 1163 method to read the NUMA configuration directly from the builtin 1164 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA 1165 instead, which also takes priority if both are compiled in. 1166 1167config X86_64_ACPI_NUMA 1168 def_bool y 1169 prompt "ACPI NUMA detection" 1170 depends on X86_64 && NUMA && ACPI && PCI 1171 select ACPI_NUMA 1172 ---help--- 1173 Enable ACPI SRAT based node topology detection. 1174 1175# Some NUMA nodes have memory ranges that span 1176# other nodes. Even though a pfn is valid and 1177# between a node's start and end pfns, it may not 1178# reside on that node. See memmap_init_zone() 1179# for details. 1180config NODES_SPAN_OTHER_NODES 1181 def_bool y 1182 depends on X86_64_ACPI_NUMA 1183 1184config NUMA_EMU 1185 bool "NUMA emulation" 1186 depends on X86_64 && NUMA 1187 ---help--- 1188 Enable NUMA emulation. A flat machine will be split 1189 into virtual nodes when booted with "numa=fake=N", where N is the 1190 number of nodes. This is only useful for debugging. 1191 1192config NODES_SHIFT 1193 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1194 range 1 9 1195 default "9" if MAXSMP 1196 default "6" if X86_64 1197 default "4" if X86_NUMAQ 1198 default "3" 1199 depends on NEED_MULTIPLE_NODES 1200 ---help--- 1201 Specify the maximum number of NUMA Nodes available on the target 1202 system. Increases memory reserved to accommodate various tables. 1203 1204config HAVE_ARCH_BOOTMEM 1205 def_bool y 1206 depends on X86_32 && NUMA 1207 1208config ARCH_HAVE_MEMORY_PRESENT 1209 def_bool y 1210 depends on X86_32 && DISCONTIGMEM 1211 1212config NEED_NODE_MEMMAP_SIZE 1213 def_bool y 1214 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1215 1216config HAVE_ARCH_ALLOC_REMAP 1217 def_bool y 1218 depends on X86_32 && NUMA 1219 1220config ARCH_FLATMEM_ENABLE 1221 def_bool y 1222 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA 1223 1224config ARCH_DISCONTIGMEM_ENABLE 1225 def_bool y 1226 depends on NUMA && X86_32 1227 1228config ARCH_DISCONTIGMEM_DEFAULT 1229 def_bool y 1230 depends on NUMA && X86_32 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 1250source "mm/Kconfig" 1251 1252config HIGHPTE 1253 bool "Allocate 3rd-level pagetables from highmem" 1254 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G) 1255 ---help--- 1256 The VM uses one page table entry for each page of physical memory. 1257 For systems with a lot of RAM, this can be wasteful of precious 1258 low memory. Setting this option will put user-space page table 1259 entries in high memory. 1260 1261config X86_CHECK_BIOS_CORRUPTION 1262 bool "Check for low memory corruption" 1263 ---help--- 1264 Periodically check for memory corruption in low memory, which 1265 is suspected to be caused by BIOS. Even when enabled in the 1266 configuration, it is disabled at runtime. Enable it by 1267 setting "memory_corruption_check=1" on the kernel command 1268 line. By default it scans the low 64k of memory every 60 1269 seconds; see the memory_corruption_check_size and 1270 memory_corruption_check_period parameters in 1271 Documentation/kernel-parameters.txt to adjust this. 1272 1273 When enabled with the default parameters, this option has 1274 almost no overhead, as it reserves a relatively small amount 1275 of memory and scans it infrequently. It both detects corruption 1276 and prevents it from affecting the running system. 1277 1278 It is, however, intended as a diagnostic tool; if repeatable 1279 BIOS-originated corruption always affects the same memory, 1280 you can use memmap= to prevent the kernel from using that 1281 memory. 1282 1283config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1284 bool "Set the default setting of memory_corruption_check" 1285 depends on X86_CHECK_BIOS_CORRUPTION 1286 default y 1287 ---help--- 1288 Set whether the default state of memory_corruption_check is 1289 on or off. 1290 1291config X86_RESERVE_LOW_64K 1292 bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen" 1293 default y 1294 ---help--- 1295 Reserve the first 64K of physical RAM on BIOSes that are known 1296 to potentially corrupt that memory range. A numbers of BIOSes are 1297 known to utilize this area during suspend/resume, so it must not 1298 be used by the kernel. 1299 1300 Set this to N if you are absolutely sure that you trust the BIOS 1301 to get all its memory reservations and usages right. 1302 1303 If you have doubts about the BIOS (e.g. suspend/resume does not 1304 work or there's kernel crashes after certain hardware hotplug 1305 events) and it's not AMI or Phoenix, then you might want to enable 1306 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical 1307 corruption patterns. 1308 1309 Say Y if unsure. 1310 1311config MATH_EMULATION 1312 bool 1313 prompt "Math emulation" if X86_32 1314 ---help--- 1315 Linux can emulate a math coprocessor (used for floating point 1316 operations) if you don't have one. 486DX and Pentium processors have 1317 a math coprocessor built in, 486SX and 386 do not, unless you added 1318 a 487DX or 387, respectively. (The messages during boot time can 1319 give you some hints here ["man dmesg"].) Everyone needs either a 1320 coprocessor or this emulation. 1321 1322 If you don't have a math coprocessor, you need to say Y here; if you 1323 say Y here even though you have a coprocessor, the coprocessor will 1324 be used nevertheless. (This behavior can be changed with the kernel 1325 command line option "no387", which comes handy if your coprocessor 1326 is broken. Try "man bootparam" or see the documentation of your boot 1327 loader (lilo or loadlin) about how to pass options to the kernel at 1328 boot time.) This means that it is a good idea to say Y here if you 1329 intend to use this kernel on different machines. 1330 1331 More information about the internals of the Linux math coprocessor 1332 emulation can be found in <file:arch/x86/math-emu/README>. 1333 1334 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1335 kernel, it won't hurt. 1336 1337config MTRR 1338 bool "MTRR (Memory Type Range Register) support" 1339 ---help--- 1340 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1341 the Memory Type Range Registers (MTRRs) may be used to control 1342 processor access to memory ranges. This is most useful if you have 1343 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1344 allows bus write transfers to be combined into a larger transfer 1345 before bursting over the PCI/AGP bus. This can increase performance 1346 of image write operations 2.5 times or more. Saying Y here creates a 1347 /proc/mtrr file which may be used to manipulate your processor's 1348 MTRRs. Typically the X server should use this. 1349 1350 This code has a reasonably generic interface so that similar 1351 control registers on other processors can be easily supported 1352 as well: 1353 1354 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1355 Registers (ARRs) which provide a similar functionality to MTRRs. For 1356 these, the ARRs are used to emulate the MTRRs. 1357 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1358 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1359 write-combining. All of these processors are supported by this code 1360 and it makes sense to say Y here if you have one of them. 1361 1362 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1363 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1364 can lead to all sorts of problems, so it's good to say Y here. 1365 1366 You can safely say Y even if your machine doesn't have MTRRs, you'll 1367 just add about 9 KB to your kernel. 1368 1369 See <file:Documentation/x86/mtrr.txt> for more information. 1370 1371config MTRR_SANITIZER 1372 def_bool y 1373 prompt "MTRR cleanup support" 1374 depends on MTRR 1375 ---help--- 1376 Convert MTRR layout from continuous to discrete, so X drivers can 1377 add writeback entries. 1378 1379 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1380 The largest mtrr entry size for a continuous block can be set with 1381 mtrr_chunk_size. 1382 1383 If unsure, say Y. 1384 1385config MTRR_SANITIZER_ENABLE_DEFAULT 1386 int "MTRR cleanup enable value (0-1)" 1387 range 0 1 1388 default "0" 1389 depends on MTRR_SANITIZER 1390 ---help--- 1391 Enable mtrr cleanup default value 1392 1393config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1394 int "MTRR cleanup spare reg num (0-7)" 1395 range 0 7 1396 default "1" 1397 depends on MTRR_SANITIZER 1398 ---help--- 1399 mtrr cleanup spare entries default, it can be changed via 1400 mtrr_spare_reg_nr=N on the kernel command line. 1401 1402config X86_PAT 1403 bool 1404 prompt "x86 PAT support" 1405 depends on MTRR 1406 ---help--- 1407 Use PAT attributes to setup page level cache control. 1408 1409 PATs are the modern equivalents of MTRRs and are much more 1410 flexible than MTRRs. 1411 1412 Say N here if you see bootup problems (boot crash, boot hang, 1413 spontaneous reboots) or a non-working video driver. 1414 1415 If unsure, say Y. 1416 1417config EFI 1418 bool "EFI runtime service support" 1419 depends on ACPI 1420 ---help--- 1421 This enables the kernel to use EFI runtime services that are 1422 available (such as the EFI variable services). 1423 1424 This option is only useful on systems that have EFI firmware. 1425 In addition, you should use the latest ELILO loader available 1426 at <http://elilo.sourceforge.net> in order to take advantage 1427 of EFI runtime services. However, even with this option, the 1428 resultant kernel should continue to boot on existing non-EFI 1429 platforms. 1430 1431config SECCOMP 1432 def_bool y 1433 prompt "Enable seccomp to safely compute untrusted bytecode" 1434 ---help--- 1435 This kernel feature is useful for number crunching applications 1436 that may need to compute untrusted bytecode during their 1437 execution. By using pipes or other transports made available to 1438 the process as file descriptors supporting the read/write 1439 syscalls, it's possible to isolate those applications in 1440 their own address space using seccomp. Once seccomp is 1441 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1442 and the task is only allowed to execute a few safe syscalls 1443 defined by each seccomp mode. 1444 1445 If unsure, say Y. Only embedded should say N here. 1446 1447config CC_STACKPROTECTOR_ALL 1448 bool 1449 1450config CC_STACKPROTECTOR 1451 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)" 1452 select CC_STACKPROTECTOR_ALL 1453 ---help--- 1454 This option turns on the -fstack-protector GCC feature. This 1455 feature puts, at the beginning of functions, a canary value on 1456 the stack just before the return address, and validates 1457 the value just before actually returning. Stack based buffer 1458 overflows (that need to overwrite this return address) now also 1459 overwrite the canary, which gets detected and the attack is then 1460 neutralized via a kernel panic. 1461 1462 This feature requires gcc version 4.2 or above, or a distribution 1463 gcc with the feature backported. Older versions are automatically 1464 detected and for those versions, this configuration option is 1465 ignored. (and a warning is printed during bootup) 1466 1467source kernel/Kconfig.hz 1468 1469config KEXEC 1470 bool "kexec system call" 1471 ---help--- 1472 kexec is a system call that implements the ability to shutdown your 1473 current kernel, and to start another kernel. It is like a reboot 1474 but it is independent of the system firmware. And like a reboot 1475 you can start any kernel with it, not just Linux. 1476 1477 The name comes from the similarity to the exec system call. 1478 1479 It is an ongoing process to be certain the hardware in a machine 1480 is properly shutdown, so do not be surprised if this code does not 1481 initially work for you. It may help to enable device hotplugging 1482 support. As of this writing the exact hardware interface is 1483 strongly in flux, so no good recommendation can be made. 1484 1485config CRASH_DUMP 1486 bool "kernel crash dumps" 1487 depends on X86_64 || (X86_32 && HIGHMEM) 1488 ---help--- 1489 Generate crash dump after being started by kexec. 1490 This should be normally only set in special crash dump kernels 1491 which are loaded in the main kernel with kexec-tools into 1492 a specially reserved region and then later executed after 1493 a crash by kdump/kexec. The crash dump kernel must be compiled 1494 to a memory address not used by the main kernel or BIOS using 1495 PHYSICAL_START, or it must be built as a relocatable image 1496 (CONFIG_RELOCATABLE=y). 1497 For more details see Documentation/kdump/kdump.txt 1498 1499config KEXEC_JUMP 1500 bool "kexec jump (EXPERIMENTAL)" 1501 depends on EXPERIMENTAL 1502 depends on KEXEC && HIBERNATION 1503 ---help--- 1504 Jump between original kernel and kexeced kernel and invoke 1505 code in physical address mode via KEXEC 1506 1507config PHYSICAL_START 1508 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP) 1509 default "0x1000000" 1510 ---help--- 1511 This gives the physical address where the kernel is loaded. 1512 1513 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1514 bzImage will decompress itself to above physical address and 1515 run from there. Otherwise, bzImage will run from the address where 1516 it has been loaded by the boot loader and will ignore above physical 1517 address. 1518 1519 In normal kdump cases one does not have to set/change this option 1520 as now bzImage can be compiled as a completely relocatable image 1521 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1522 address. This option is mainly useful for the folks who don't want 1523 to use a bzImage for capturing the crash dump and want to use a 1524 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1525 to be specifically compiled to run from a specific memory area 1526 (normally a reserved region) and this option comes handy. 1527 1528 So if you are using bzImage for capturing the crash dump, 1529 leave the value here unchanged to 0x1000000 and set 1530 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1531 for capturing the crash dump change this value to start of 1532 the reserved region. In other words, it can be set based on 1533 the "X" value as specified in the "crashkernel=YM@XM" 1534 command line boot parameter passed to the panic-ed 1535 kernel. Please take a look at Documentation/kdump/kdump.txt 1536 for more details about crash dumps. 1537 1538 Usage of bzImage for capturing the crash dump is recommended as 1539 one does not have to build two kernels. Same kernel can be used 1540 as production kernel and capture kernel. Above option should have 1541 gone away after relocatable bzImage support is introduced. But it 1542 is present because there are users out there who continue to use 1543 vmlinux for dump capture. This option should go away down the 1544 line. 1545 1546 Don't change this unless you know what you are doing. 1547 1548config RELOCATABLE 1549 bool "Build a relocatable kernel" 1550 default y 1551 ---help--- 1552 This builds a kernel image that retains relocation information 1553 so it can be loaded someplace besides the default 1MB. 1554 The relocations tend to make the kernel binary about 10% larger, 1555 but are discarded at runtime. 1556 1557 One use is for the kexec on panic case where the recovery kernel 1558 must live at a different physical address than the primary 1559 kernel. 1560 1561 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1562 it has been loaded at and the compile time physical address 1563 (CONFIG_PHYSICAL_START) is ignored. 1564 1565# Relocation on x86-32 needs some additional build support 1566config X86_NEED_RELOCS 1567 def_bool y 1568 depends on X86_32 && RELOCATABLE 1569 1570config PHYSICAL_ALIGN 1571 hex 1572 prompt "Alignment value to which kernel should be aligned" if X86_32 1573 default "0x1000000" 1574 range 0x2000 0x1000000 1575 ---help--- 1576 This value puts the alignment restrictions on physical address 1577 where kernel is loaded and run from. Kernel is compiled for an 1578 address which meets above alignment restriction. 1579 1580 If bootloader loads the kernel at a non-aligned address and 1581 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1582 address aligned to above value and run from there. 1583 1584 If bootloader loads the kernel at a non-aligned address and 1585 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1586 load address and decompress itself to the address it has been 1587 compiled for and run from there. The address for which kernel is 1588 compiled already meets above alignment restrictions. Hence the 1589 end result is that kernel runs from a physical address meeting 1590 above alignment restrictions. 1591 1592 Don't change this unless you know what you are doing. 1593 1594config HOTPLUG_CPU 1595 bool "Support for hot-pluggable CPUs" 1596 depends on SMP && HOTPLUG 1597 ---help--- 1598 Say Y here to allow turning CPUs off and on. CPUs can be 1599 controlled through /sys/devices/system/cpu. 1600 ( Note: power management support will enable this option 1601 automatically on SMP systems. ) 1602 Say N if you want to disable CPU hotplug. 1603 1604config COMPAT_VDSO 1605 def_bool y 1606 prompt "Compat VDSO support" 1607 depends on X86_32 || IA32_EMULATION 1608 ---help--- 1609 Map the 32-bit VDSO to the predictable old-style address too. 1610 ---help--- 1611 Say N here if you are running a sufficiently recent glibc 1612 version (2.3.3 or later), to remove the high-mapped 1613 VDSO mapping and to exclusively use the randomized VDSO. 1614 1615 If unsure, say Y. 1616 1617config CMDLINE_BOOL 1618 bool "Built-in kernel command line" 1619 default n 1620 ---help--- 1621 Allow for specifying boot arguments to the kernel at 1622 build time. On some systems (e.g. embedded ones), it is 1623 necessary or convenient to provide some or all of the 1624 kernel boot arguments with the kernel itself (that is, 1625 to not rely on the boot loader to provide them.) 1626 1627 To compile command line arguments into the kernel, 1628 set this option to 'Y', then fill in the 1629 the boot arguments in CONFIG_CMDLINE. 1630 1631 Systems with fully functional boot loaders (i.e. non-embedded) 1632 should leave this option set to 'N'. 1633 1634config CMDLINE 1635 string "Built-in kernel command string" 1636 depends on CMDLINE_BOOL 1637 default "" 1638 ---help--- 1639 Enter arguments here that should be compiled into the kernel 1640 image and used at boot time. If the boot loader provides a 1641 command line at boot time, it is appended to this string to 1642 form the full kernel command line, when the system boots. 1643 1644 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 1645 change this behavior. 1646 1647 In most cases, the command line (whether built-in or provided 1648 by the boot loader) should specify the device for the root 1649 file system. 1650 1651config CMDLINE_OVERRIDE 1652 bool "Built-in command line overrides boot loader arguments" 1653 default n 1654 depends on CMDLINE_BOOL 1655 ---help--- 1656 Set this option to 'Y' to have the kernel ignore the boot loader 1657 command line, and use ONLY the built-in command line. 1658 1659 This is used to work around broken boot loaders. This should 1660 be set to 'N' under normal conditions. 1661 1662endmenu 1663 1664config ARCH_ENABLE_MEMORY_HOTPLUG 1665 def_bool y 1666 depends on X86_64 || (X86_32 && HIGHMEM) 1667 1668config ARCH_ENABLE_MEMORY_HOTREMOVE 1669 def_bool y 1670 depends on MEMORY_HOTPLUG 1671 1672config HAVE_ARCH_EARLY_PFN_TO_NID 1673 def_bool X86_64 1674 depends on NUMA 1675 1676menu "Power management and ACPI options" 1677 1678config ARCH_HIBERNATION_HEADER 1679 def_bool y 1680 depends on X86_64 && HIBERNATION 1681 1682source "kernel/power/Kconfig" 1683 1684source "drivers/acpi/Kconfig" 1685 1686config X86_APM_BOOT 1687 bool 1688 default y 1689 depends on APM || APM_MODULE 1690 1691menuconfig APM 1692 tristate "APM (Advanced Power Management) BIOS support" 1693 depends on X86_32 && PM_SLEEP 1694 ---help--- 1695 APM is a BIOS specification for saving power using several different 1696 techniques. This is mostly useful for battery powered laptops with 1697 APM compliant BIOSes. If you say Y here, the system time will be 1698 reset after a RESUME operation, the /proc/apm device will provide 1699 battery status information, and user-space programs will receive 1700 notification of APM "events" (e.g. battery status change). 1701 1702 If you select "Y" here, you can disable actual use of the APM 1703 BIOS by passing the "apm=off" option to the kernel at boot time. 1704 1705 Note that the APM support is almost completely disabled for 1706 machines with more than one CPU. 1707 1708 In order to use APM, you will need supporting software. For location 1709 and more information, read <file:Documentation/power/pm.txt> and the 1710 Battery Powered Linux mini-HOWTO, available from 1711 <http://www.tldp.org/docs.html#howto>. 1712 1713 This driver does not spin down disk drives (see the hdparm(8) 1714 manpage ("man 8 hdparm") for that), and it doesn't turn off 1715 VESA-compliant "green" monitors. 1716 1717 This driver does not support the TI 4000M TravelMate and the ACER 1718 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1719 desktop machines also don't have compliant BIOSes, and this driver 1720 may cause those machines to panic during the boot phase. 1721 1722 Generally, if you don't have a battery in your machine, there isn't 1723 much point in using this driver and you should say N. If you get 1724 random kernel OOPSes or reboots that don't seem to be related to 1725 anything, try disabling/enabling this option (or disabling/enabling 1726 APM in your BIOS). 1727 1728 Some other things you should try when experiencing seemingly random, 1729 "weird" problems: 1730 1731 1) make sure that you have enough swap space and that it is 1732 enabled. 1733 2) pass the "no-hlt" option to the kernel 1734 3) switch on floating point emulation in the kernel and pass 1735 the "no387" option to the kernel 1736 4) pass the "floppy=nodma" option to the kernel 1737 5) pass the "mem=4M" option to the kernel (thereby disabling 1738 all but the first 4 MB of RAM) 1739 6) make sure that the CPU is not over clocked. 1740 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1741 8) disable the cache from your BIOS settings 1742 9) install a fan for the video card or exchange video RAM 1743 10) install a better fan for the CPU 1744 11) exchange RAM chips 1745 12) exchange the motherboard. 1746 1747 To compile this driver as a module, choose M here: the 1748 module will be called apm. 1749 1750if APM 1751 1752config APM_IGNORE_USER_SUSPEND 1753 bool "Ignore USER SUSPEND" 1754 ---help--- 1755 This option will ignore USER SUSPEND requests. On machines with a 1756 compliant APM BIOS, you want to say N. However, on the NEC Versa M 1757 series notebooks, it is necessary to say Y because of a BIOS bug. 1758 1759config APM_DO_ENABLE 1760 bool "Enable PM at boot time" 1761 ---help--- 1762 Enable APM features at boot time. From page 36 of the APM BIOS 1763 specification: "When disabled, the APM BIOS does not automatically 1764 power manage devices, enter the Standby State, enter the Suspend 1765 State, or take power saving steps in response to CPU Idle calls." 1766 This driver will make CPU Idle calls when Linux is idle (unless this 1767 feature is turned off -- see "Do CPU IDLE calls", below). This 1768 should always save battery power, but more complicated APM features 1769 will be dependent on your BIOS implementation. You may need to turn 1770 this option off if your computer hangs at boot time when using APM 1771 support, or if it beeps continuously instead of suspending. Turn 1772 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1773 T400CDT. This is off by default since most machines do fine without 1774 this feature. 1775 1776config APM_CPU_IDLE 1777 bool "Make CPU Idle calls when idle" 1778 ---help--- 1779 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 1780 On some machines, this can activate improved power savings, such as 1781 a slowed CPU clock rate, when the machine is idle. These idle calls 1782 are made after the idle loop has run for some length of time (e.g., 1783 333 mS). On some machines, this will cause a hang at boot time or 1784 whenever the CPU becomes idle. (On machines with more than one CPU, 1785 this option does nothing.) 1786 1787config APM_DISPLAY_BLANK 1788 bool "Enable console blanking using APM" 1789 ---help--- 1790 Enable console blanking using the APM. Some laptops can use this to 1791 turn off the LCD backlight when the screen blanker of the Linux 1792 virtual console blanks the screen. Note that this is only used by 1793 the virtual console screen blanker, and won't turn off the backlight 1794 when using the X Window system. This also doesn't have anything to 1795 do with your VESA-compliant power-saving monitor. Further, this 1796 option doesn't work for all laptops -- it might not turn off your 1797 backlight at all, or it might print a lot of errors to the console, 1798 especially if you are using gpm. 1799 1800config APM_ALLOW_INTS 1801 bool "Allow interrupts during APM BIOS calls" 1802 ---help--- 1803 Normally we disable external interrupts while we are making calls to 1804 the APM BIOS as a measure to lessen the effects of a badly behaving 1805 BIOS implementation. The BIOS should reenable interrupts if it 1806 needs to. Unfortunately, some BIOSes do not -- especially those in 1807 many of the newer IBM Thinkpads. If you experience hangs when you 1808 suspend, try setting this to Y. Otherwise, say N. 1809 1810endif # APM 1811 1812source "arch/x86/kernel/cpu/cpufreq/Kconfig" 1813 1814source "drivers/cpuidle/Kconfig" 1815 1816source "drivers/idle/Kconfig" 1817 1818endmenu 1819 1820 1821menu "Bus options (PCI etc.)" 1822 1823config PCI 1824 bool "PCI support" 1825 default y 1826 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC) 1827 ---help--- 1828 Find out whether you have a PCI motherboard. PCI is the name of a 1829 bus system, i.e. the way the CPU talks to the other stuff inside 1830 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 1831 VESA. If you have PCI, say Y, otherwise N. 1832 1833choice 1834 prompt "PCI access mode" 1835 depends on X86_32 && PCI 1836 default PCI_GOANY 1837 ---help--- 1838 On PCI systems, the BIOS can be used to detect the PCI devices and 1839 determine their configuration. However, some old PCI motherboards 1840 have BIOS bugs and may crash if this is done. Also, some embedded 1841 PCI-based systems don't have any BIOS at all. Linux can also try to 1842 detect the PCI hardware directly without using the BIOS. 1843 1844 With this option, you can specify how Linux should detect the 1845 PCI devices. If you choose "BIOS", the BIOS will be used, 1846 if you choose "Direct", the BIOS won't be used, and if you 1847 choose "MMConfig", then PCI Express MMCONFIG will be used. 1848 If you choose "Any", the kernel will try MMCONFIG, then the 1849 direct access method and falls back to the BIOS if that doesn't 1850 work. If unsure, go with the default, which is "Any". 1851 1852config PCI_GOBIOS 1853 bool "BIOS" 1854 1855config PCI_GOMMCONFIG 1856 bool "MMConfig" 1857 1858config PCI_GODIRECT 1859 bool "Direct" 1860 1861config PCI_GOOLPC 1862 bool "OLPC" 1863 depends on OLPC 1864 1865config PCI_GOANY 1866 bool "Any" 1867 1868endchoice 1869 1870config PCI_BIOS 1871 def_bool y 1872 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 1873 1874# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 1875config PCI_DIRECT 1876 def_bool y 1877 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC)) 1878 1879config PCI_MMCONFIG 1880 def_bool y 1881 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY) 1882 1883config PCI_OLPC 1884 def_bool y 1885 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 1886 1887config PCI_DOMAINS 1888 def_bool y 1889 depends on PCI 1890 1891config PCI_MMCONFIG 1892 bool "Support mmconfig PCI config space access" 1893 depends on X86_64 && PCI && ACPI 1894 1895config DMAR 1896 bool "Support for DMA Remapping Devices (EXPERIMENTAL)" 1897 depends on PCI_MSI && ACPI && EXPERIMENTAL 1898 help 1899 DMA remapping (DMAR) devices support enables independent address 1900 translations for Direct Memory Access (DMA) from devices. 1901 These DMA remapping devices are reported via ACPI tables 1902 and include PCI device scope covered by these DMA 1903 remapping devices. 1904 1905config DMAR_DEFAULT_ON 1906 def_bool y 1907 prompt "Enable DMA Remapping Devices by default" 1908 depends on DMAR 1909 help 1910 Selecting this option will enable a DMAR device at boot time if 1911 one is found. If this option is not selected, DMAR support can 1912 be enabled by passing intel_iommu=on to the kernel. It is 1913 recommended you say N here while the DMAR code remains 1914 experimental. 1915 1916config DMAR_BROKEN_GFX_WA 1917 def_bool n 1918 prompt "Workaround broken graphics drivers (going away soon)" 1919 depends on DMAR 1920 ---help--- 1921 Current Graphics drivers tend to use physical address 1922 for DMA and avoid using DMA APIs. Setting this config 1923 option permits the IOMMU driver to set a unity map for 1924 all the OS-visible memory. Hence the driver can continue 1925 to use physical addresses for DMA, at least until this 1926 option is removed in the 2.6.32 kernel. 1927 1928config DMAR_FLOPPY_WA 1929 def_bool y 1930 depends on DMAR 1931 ---help--- 1932 Floppy disk drivers are known to bypass DMA API calls 1933 thereby failing to work when IOMMU is enabled. This 1934 workaround will setup a 1:1 mapping for the first 1935 16MiB to make floppy (an ISA device) work. 1936 1937config INTR_REMAP 1938 bool "Support for Interrupt Remapping (EXPERIMENTAL)" 1939 depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL 1940 ---help--- 1941 Supports Interrupt remapping for IO-APIC and MSI devices. 1942 To use x2apic mode in the CPU's which support x2APIC enhancements or 1943 to support platforms with CPU's having > 8 bit APIC ID, say Y. 1944 1945source "drivers/pci/pcie/Kconfig" 1946 1947source "drivers/pci/Kconfig" 1948 1949# x86_64 have no ISA slots, but do have ISA-style DMA. 1950config ISA_DMA_API 1951 def_bool y 1952 1953if X86_32 1954 1955config ISA 1956 bool "ISA support" 1957 ---help--- 1958 Find out whether you have ISA slots on your motherboard. ISA is the 1959 name of a bus system, i.e. the way the CPU talks to the other stuff 1960 inside your box. Other bus systems are PCI, EISA, MicroChannel 1961 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 1962 newer boards don't support it. If you have ISA, say Y, otherwise N. 1963 1964config EISA 1965 bool "EISA support" 1966 depends on ISA 1967 ---help--- 1968 The Extended Industry Standard Architecture (EISA) bus was 1969 developed as an open alternative to the IBM MicroChannel bus. 1970 1971 The EISA bus provided some of the features of the IBM MicroChannel 1972 bus while maintaining backward compatibility with cards made for 1973 the older ISA bus. The EISA bus saw limited use between 1988 and 1974 1995 when it was made obsolete by the PCI bus. 1975 1976 Say Y here if you are building a kernel for an EISA-based machine. 1977 1978 Otherwise, say N. 1979 1980source "drivers/eisa/Kconfig" 1981 1982config MCA 1983 bool "MCA support" 1984 ---help--- 1985 MicroChannel Architecture is found in some IBM PS/2 machines and 1986 laptops. It is a bus system similar to PCI or ISA. See 1987 <file:Documentation/mca.txt> (and especially the web page given 1988 there) before attempting to build an MCA bus kernel. 1989 1990source "drivers/mca/Kconfig" 1991 1992config SCx200 1993 tristate "NatSemi SCx200 support" 1994 ---help--- 1995 This provides basic support for National Semiconductor's 1996 (now AMD's) Geode processors. The driver probes for the 1997 PCI-IDs of several on-chip devices, so its a good dependency 1998 for other scx200_* drivers. 1999 2000 If compiled as a module, the driver is named scx200. 2001 2002config SCx200HR_TIMER 2003 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2004 depends on SCx200 && GENERIC_TIME 2005 default y 2006 ---help--- 2007 This driver provides a clocksource built upon the on-chip 2008 27MHz high-resolution timer. Its also a workaround for 2009 NSC Geode SC-1100's buggy TSC, which loses time when the 2010 processor goes idle (as is done by the scheduler). The 2011 other workaround is idle=poll boot option. 2012 2013config GEODE_MFGPT_TIMER 2014 def_bool y 2015 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events" 2016 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS 2017 ---help--- 2018 This driver provides a clock event source based on the MFGPT 2019 timer(s) in the CS5535 and CS5536 companion chip for the geode. 2020 MFGPTs have a better resolution and max interval than the 2021 generic PIT, and are suitable for use as high-res timers. 2022 2023config OLPC 2024 bool "One Laptop Per Child support" 2025 default n 2026 ---help--- 2027 Add support for detecting the unique features of the OLPC 2028 XO hardware. 2029 2030endif # X86_32 2031 2032config K8_NB 2033 def_bool y 2034 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA))) 2035 2036source "drivers/pcmcia/Kconfig" 2037 2038source "drivers/pci/hotplug/Kconfig" 2039 2040endmenu 2041 2042 2043menu "Executable file formats / Emulations" 2044 2045source "fs/Kconfig.binfmt" 2046 2047config IA32_EMULATION 2048 bool "IA32 Emulation" 2049 depends on X86_64 2050 select COMPAT_BINFMT_ELF 2051 ---help--- 2052 Include code to run 32-bit programs under a 64-bit kernel. You should 2053 likely turn this on, unless you're 100% sure that you don't have any 2054 32-bit programs left. 2055 2056config IA32_AOUT 2057 tristate "IA32 a.out support" 2058 depends on IA32_EMULATION 2059 ---help--- 2060 Support old a.out binaries in the 32bit emulation. 2061 2062config COMPAT 2063 def_bool y 2064 depends on IA32_EMULATION 2065 2066config COMPAT_FOR_U64_ALIGNMENT 2067 def_bool COMPAT 2068 depends on X86_64 2069 2070config SYSVIPC_COMPAT 2071 def_bool y 2072 depends on COMPAT && SYSVIPC 2073 2074endmenu 2075 2076 2077config HAVE_ATOMIC_IOMAP 2078 def_bool y 2079 depends on X86_32 2080 2081source "net/Kconfig" 2082 2083source "drivers/Kconfig" 2084 2085source "drivers/firmware/Kconfig" 2086 2087source "fs/Kconfig" 2088 2089source "arch/x86/Kconfig.debug" 2090 2091source "security/Kconfig" 2092 2093source "crypto/Kconfig" 2094 2095source "arch/x86/kvm/Kconfig" 2096 2097source "lib/Kconfig" 2098