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_UNSTABLE_SCHED_CLOCK 22 select HAVE_IDE 23 select HAVE_OPROFILE 24 select HAVE_KPROBES 25 select HAVE_KRETPROBES 26 select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64) 27 select HAVE_ARCH_KGDB if !X86_VOYAGER 28 29config ARCH_DEFCONFIG 30 string 31 default "arch/x86/configs/i386_defconfig" if X86_32 32 default "arch/x86/configs/x86_64_defconfig" if X86_64 33 34 35config GENERIC_LOCKBREAK 36 def_bool n 37 38config GENERIC_TIME 39 def_bool y 40 41config GENERIC_CMOS_UPDATE 42 def_bool y 43 44config CLOCKSOURCE_WATCHDOG 45 def_bool y 46 47config GENERIC_CLOCKEVENTS 48 def_bool y 49 50config GENERIC_CLOCKEVENTS_BROADCAST 51 def_bool y 52 depends on X86_64 || (X86_32 && X86_LOCAL_APIC) 53 54config LOCKDEP_SUPPORT 55 def_bool y 56 57config STACKTRACE_SUPPORT 58 def_bool y 59 60config HAVE_LATENCYTOP_SUPPORT 61 def_bool y 62 63config FAST_CMPXCHG_LOCAL 64 bool 65 default y 66 67config MMU 68 def_bool y 69 70config ZONE_DMA 71 def_bool y 72 73config SBUS 74 bool 75 76config GENERIC_ISA_DMA 77 def_bool y 78 79config GENERIC_IOMAP 80 def_bool y 81 82config GENERIC_BUG 83 def_bool y 84 depends on BUG 85 86config GENERIC_HWEIGHT 87 def_bool y 88 89config GENERIC_GPIO 90 def_bool n 91 92config ARCH_MAY_HAVE_PC_FDC 93 def_bool y 94 95config RWSEM_GENERIC_SPINLOCK 96 def_bool !X86_XADD 97 98config RWSEM_XCHGADD_ALGORITHM 99 def_bool X86_XADD 100 101config ARCH_HAS_ILOG2_U32 102 def_bool n 103 104config ARCH_HAS_ILOG2_U64 105 def_bool n 106 107config ARCH_HAS_CPU_IDLE_WAIT 108 def_bool y 109 110config GENERIC_CALIBRATE_DELAY 111 def_bool y 112 113config GENERIC_TIME_VSYSCALL 114 bool 115 default X86_64 116 117config ARCH_HAS_CPU_RELAX 118 def_bool y 119 120config ARCH_HAS_CACHE_LINE_SIZE 121 def_bool y 122 123config HAVE_SETUP_PER_CPU_AREA 124 def_bool X86_64_SMP || (X86_SMP && !X86_VOYAGER) 125 126config HAVE_CPUMASK_OF_CPU_MAP 127 def_bool X86_64_SMP 128 129config ARCH_HIBERNATION_POSSIBLE 130 def_bool y 131 depends on !SMP || !X86_VOYAGER 132 133config ARCH_SUSPEND_POSSIBLE 134 def_bool y 135 depends on !X86_VOYAGER 136 137config ZONE_DMA32 138 bool 139 default X86_64 140 141config ARCH_POPULATES_NODE_MAP 142 def_bool y 143 144config AUDIT_ARCH 145 bool 146 default X86_64 147 148config ARCH_SUPPORTS_AOUT 149 def_bool y 150 151config ARCH_SUPPORTS_OPTIMIZED_INLINING 152 def_bool y 153 154# Use the generic interrupt handling code in kernel/irq/: 155config GENERIC_HARDIRQS 156 bool 157 default y 158 159config GENERIC_IRQ_PROBE 160 bool 161 default y 162 163config GENERIC_PENDING_IRQ 164 bool 165 depends on GENERIC_HARDIRQS && SMP 166 default y 167 168config X86_SMP 169 bool 170 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64) 171 default y 172 173config X86_32_SMP 174 def_bool y 175 depends on X86_32 && SMP 176 177config X86_64_SMP 178 def_bool y 179 depends on X86_64 && SMP 180 181config X86_HT 182 bool 183 depends on SMP 184 depends on (X86_32 && !(X86_VISWS || X86_VOYAGER)) || X86_64 185 default y 186 187config X86_BIOS_REBOOT 188 bool 189 depends on !X86_VISWS && !X86_VOYAGER 190 default y 191 192config X86_TRAMPOLINE 193 bool 194 depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP) 195 default y 196 197config KTIME_SCALAR 198 def_bool X86_32 199source "init/Kconfig" 200 201menu "Processor type and features" 202 203source "kernel/time/Kconfig" 204 205config SMP 206 bool "Symmetric multi-processing support" 207 ---help--- 208 This enables support for systems with more than one CPU. If you have 209 a system with only one CPU, like most personal computers, say N. If 210 you have a system with more than one CPU, say Y. 211 212 If you say N here, the kernel will run on single and multiprocessor 213 machines, but will use only one CPU of a multiprocessor machine. If 214 you say Y here, the kernel will run on many, but not all, 215 singleprocessor machines. On a singleprocessor machine, the kernel 216 will run faster if you say N here. 217 218 Note that if you say Y here and choose architecture "586" or 219 "Pentium" under "Processor family", the kernel will not work on 486 220 architectures. Similarly, multiprocessor kernels for the "PPro" 221 architecture may not work on all Pentium based boards. 222 223 People using multiprocessor machines who say Y here should also say 224 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 225 Management" code will be disabled if you say Y here. 226 227 See also <file:Documentation/i386/IO-APIC.txt>, 228 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 229 <http://www.tldp.org/docs.html#howto>. 230 231 If you don't know what to do here, say N. 232 233config X86_FIND_SMP_CONFIG 234 def_bool y 235 depends on X86_MPPARSE || X86_VOYAGER || X86_VISWS 236 237if ACPI 238config X86_MPPARSE 239 def_bool y 240 bool "Enable MPS table" 241 depends on X86_LOCAL_APIC && !X86_VISWS 242 help 243 For old smp systems that do not have proper acpi support. Newer systems 244 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 245endif 246 247if !ACPI 248config X86_MPPARSE 249 def_bool y 250 depends on X86_LOCAL_APIC && !X86_VISWS 251endif 252 253choice 254 prompt "Subarchitecture Type" 255 default X86_PC 256 257config X86_PC 258 bool "PC-compatible" 259 help 260 Choose this option if your computer is a standard PC or compatible. 261 262config X86_ELAN 263 bool "AMD Elan" 264 depends on X86_32 265 help 266 Select this for an AMD Elan processor. 267 268 Do not use this option for K6/Athlon/Opteron processors! 269 270 If unsure, choose "PC-compatible" instead. 271 272config X86_VOYAGER 273 bool "Voyager (NCR)" 274 depends on X86_32 && (SMP || BROKEN) && !PCI 275 help 276 Voyager is an MCA-based 32-way capable SMP architecture proprietary 277 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based. 278 279 *** WARNING *** 280 281 If you do not specifically know you have a Voyager based machine, 282 say N here, otherwise the kernel you build will not be bootable. 283 284config X86_VISWS 285 bool "SGI 320/540 (Visual Workstation)" 286 depends on X86_32 && !PCI 287 help 288 The SGI Visual Workstation series is an IA32-based workstation 289 based on SGI systems chips with some legacy PC hardware attached. 290 291 Say Y here to create a kernel to run on the SGI 320 or 540. 292 293 A kernel compiled for the Visual Workstation will not run on PCs 294 and vice versa. See <file:Documentation/sgi-visws.txt> for details. 295 296config X86_GENERICARCH 297 bool "Generic architecture" 298 depends on X86_32 299 help 300 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default 301 subarchitectures. It is intended for a generic binary kernel. 302 if you select them all, kernel will probe it one by one. and will 303 fallback to default. 304 305if X86_GENERICARCH 306 307config X86_NUMAQ 308 bool "NUMAQ (IBM/Sequent)" 309 depends on SMP && X86_32 && PCI && X86_MPPARSE 310 select NUMA 311 help 312 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent) 313 NUMA multiquad box. This changes the way that processors are 314 bootstrapped, and uses Clustered Logical APIC addressing mode instead 315 of Flat Logical. You will need a new lynxer.elf file to flash your 316 firmware with - send email to <Martin.Bligh@us.ibm.com>. 317 318config X86_SUMMIT 319 bool "Summit/EXA (IBM x440)" 320 depends on X86_32 && SMP 321 help 322 This option is needed for IBM systems that use the Summit/EXA chipset. 323 In particular, it is needed for the x440. 324 325config X86_ES7000 326 bool "Support for Unisys ES7000 IA32 series" 327 depends on X86_32 && SMP 328 help 329 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is 330 supposed to run on an IA32-based Unisys ES7000 system. 331 332config X86_BIGSMP 333 bool "Support for big SMP systems with more than 8 CPUs" 334 depends on X86_32 && SMP 335 help 336 This option is needed for the systems that have more than 8 CPUs 337 and if the system is not of any sub-arch type above. 338 339endif 340 341config X86_RDC321X 342 bool "RDC R-321x SoC" 343 depends on X86_32 344 select M486 345 select X86_REBOOTFIXUPS 346 select GENERIC_GPIO 347 select LEDS_CLASS 348 select LEDS_GPIO 349 select NEW_LEDS 350 help 351 This option is needed for RDC R-321x system-on-chip, also known 352 as R-8610-(G). 353 If you don't have one of these chips, you should say N here. 354 355config X86_VSMP 356 bool "Support for ScaleMP vSMP" 357 select PARAVIRT 358 depends on X86_64 && !PCI 359 help 360 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 361 supposed to run on these EM64T-based machines. Only choose this option 362 if you have one of these machines. 363 364endchoice 365 366config SCHED_NO_NO_OMIT_FRAME_POINTER 367 def_bool y 368 prompt "Single-depth WCHAN output" 369 depends on X86_32 370 help 371 Calculate simpler /proc/<PID>/wchan values. If this option 372 is disabled then wchan values will recurse back to the 373 caller function. This provides more accurate wchan values, 374 at the expense of slightly more scheduling overhead. 375 376 If in doubt, say "Y". 377 378menuconfig PARAVIRT_GUEST 379 bool "Paravirtualized guest support" 380 help 381 Say Y here to get to see options related to running Linux under 382 various hypervisors. This option alone does not add any kernel code. 383 384 If you say N, all options in this submenu will be skipped and disabled. 385 386if PARAVIRT_GUEST 387 388source "arch/x86/xen/Kconfig" 389 390config VMI 391 bool "VMI Guest support" 392 select PARAVIRT 393 depends on X86_32 394 depends on !(X86_VISWS || X86_VOYAGER) 395 help 396 VMI provides a paravirtualized interface to the VMware ESX server 397 (it could be used by other hypervisors in theory too, but is not 398 at the moment), by linking the kernel to a GPL-ed ROM module 399 provided by the hypervisor. 400 401config KVM_CLOCK 402 bool "KVM paravirtualized clock" 403 select PARAVIRT 404 select PARAVIRT_CLOCK 405 depends on !(X86_VISWS || X86_VOYAGER) 406 help 407 Turning on this option will allow you to run a paravirtualized clock 408 when running over the KVM hypervisor. Instead of relying on a PIT 409 (or probably other) emulation by the underlying device model, the host 410 provides the guest with timing infrastructure such as time of day, and 411 system time 412 413config KVM_GUEST 414 bool "KVM Guest support" 415 select PARAVIRT 416 depends on !(X86_VISWS || X86_VOYAGER) 417 help 418 This option enables various optimizations for running under the KVM 419 hypervisor. 420 421source "arch/x86/lguest/Kconfig" 422 423config PARAVIRT 424 bool "Enable paravirtualization code" 425 depends on !(X86_VISWS || X86_VOYAGER) 426 help 427 This changes the kernel so it can modify itself when it is run 428 under a hypervisor, potentially improving performance significantly 429 over full virtualization. However, when run without a hypervisor 430 the kernel is theoretically slower and slightly larger. 431 432config PARAVIRT_CLOCK 433 bool 434 default n 435 436endif 437 438config PARAVIRT_DEBUG 439 bool "paravirt-ops debugging" 440 depends on PARAVIRT && DEBUG_KERNEL 441 help 442 Enable to debug paravirt_ops internals. Specifically, BUG if 443 a paravirt_op is missing when it is called. 444 445config MEMTEST 446 bool "Memtest" 447 depends on X86_64 448 default y 449 help 450 This option adds a kernel parameter 'memtest', which allows memtest 451 to be set. 452 memtest=0, mean disabled; -- default 453 memtest=1, mean do 1 test pattern; 454 ... 455 memtest=4, mean do 4 test patterns. 456 If you are unsure how to answer this question, answer Y. 457 458config ACPI_SRAT 459 def_bool y 460 depends on X86_32 && ACPI && NUMA && X86_GENERICARCH 461 select ACPI_NUMA 462 463config X86_SUMMIT_NUMA 464 def_bool y 465 depends on X86_32 && NUMA && X86_GENERICARCH 466 467config X86_CYCLONE_TIMER 468 def_bool y 469 depends on X86_GENERICARCH 470 471config ES7000_CLUSTERED_APIC 472 def_bool y 473 depends on SMP && X86_ES7000 && MPENTIUMIII 474 475source "arch/x86/Kconfig.cpu" 476 477config HPET_TIMER 478 def_bool X86_64 479 prompt "HPET Timer Support" if X86_32 480 help 481 Use the IA-PC HPET (High Precision Event Timer) to manage 482 time in preference to the PIT and RTC, if a HPET is 483 present. 484 HPET is the next generation timer replacing legacy 8254s. 485 The HPET provides a stable time base on SMP 486 systems, unlike the TSC, but it is more expensive to access, 487 as it is off-chip. You can find the HPET spec at 488 <http://www.intel.com/hardwaredesign/hpetspec.htm>. 489 490 You can safely choose Y here. However, HPET will only be 491 activated if the platform and the BIOS support this feature. 492 Otherwise the 8254 will be used for timing services. 493 494 Choose N to continue using the legacy 8254 timer. 495 496config HPET_EMULATE_RTC 497 def_bool y 498 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 499 500# Mark as embedded because too many people got it wrong. 501# The code disables itself when not needed. 502config DMI 503 default y 504 bool "Enable DMI scanning" if EMBEDDED 505 help 506 Enabled scanning of DMI to identify machine quirks. Say Y 507 here unless you have verified that your setup is not 508 affected by entries in the DMI blacklist. Required by PNP 509 BIOS code. 510 511config GART_IOMMU 512 bool "GART IOMMU support" if EMBEDDED 513 default y 514 select SWIOTLB 515 select AGP 516 depends on X86_64 && PCI 517 help 518 Support for full DMA access of devices with 32bit memory access only 519 on systems with more than 3GB. This is usually needed for USB, 520 sound, many IDE/SATA chipsets and some other devices. 521 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART 522 based hardware IOMMU and a software bounce buffer based IOMMU used 523 on Intel systems and as fallback. 524 The code is only active when needed (enough memory and limited 525 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified 526 too. 527 528config CALGARY_IOMMU 529 bool "IBM Calgary IOMMU support" 530 select SWIOTLB 531 depends on X86_64 && PCI && EXPERIMENTAL 532 help 533 Support for hardware IOMMUs in IBM's xSeries x366 and x460 534 systems. Needed to run systems with more than 3GB of memory 535 properly with 32-bit PCI devices that do not support DAC 536 (Double Address Cycle). Calgary also supports bus level 537 isolation, where all DMAs pass through the IOMMU. This 538 prevents them from going anywhere except their intended 539 destination. This catches hard-to-find kernel bugs and 540 mis-behaving drivers and devices that do not use the DMA-API 541 properly to set up their DMA buffers. The IOMMU can be 542 turned off at boot time with the iommu=off parameter. 543 Normally the kernel will make the right choice by itself. 544 If unsure, say Y. 545 546config CALGARY_IOMMU_ENABLED_BY_DEFAULT 547 def_bool y 548 prompt "Should Calgary be enabled by default?" 549 depends on CALGARY_IOMMU 550 help 551 Should Calgary be enabled by default? if you choose 'y', Calgary 552 will be used (if it exists). If you choose 'n', Calgary will not be 553 used even if it exists. If you choose 'n' and would like to use 554 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 555 If unsure, say Y. 556 557config AMD_IOMMU 558 bool "AMD IOMMU support" 559 select SWIOTLB 560 depends on X86_64 && PCI && ACPI 561 help 562 With this option you can enable support for AMD IOMMU hardware in 563 your system. An IOMMU is a hardware component which provides 564 remapping of DMA memory accesses from devices. With an AMD IOMMU you 565 can isolate the the DMA memory of different devices and protect the 566 system from misbehaving device drivers or hardware. 567 568 You can find out if your system has an AMD IOMMU if you look into 569 your BIOS for an option to enable it or if you have an IVRS ACPI 570 table. 571 572# need this always selected by IOMMU for the VIA workaround 573config SWIOTLB 574 bool 575 help 576 Support for software bounce buffers used on x86-64 systems 577 which don't have a hardware IOMMU (e.g. the current generation 578 of Intel's x86-64 CPUs). Using this PCI devices which can only 579 access 32-bits of memory can be used on systems with more than 580 3 GB of memory. If unsure, say Y. 581 582config IOMMU_HELPER 583 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB) 584config MAXSMP 585 bool "Configure Maximum number of SMP Processors and NUMA Nodes" 586 depends on X86_64 && SMP 587 default n 588 help 589 Configure maximum number of CPUS and NUMA Nodes for this architecture. 590 If unsure, say N. 591 592if MAXSMP 593config NR_CPUS 594 int 595 default "4096" 596endif 597 598if !MAXSMP 599config NR_CPUS 600 int "Maximum number of CPUs (2-4096)" 601 range 2 4096 602 depends on SMP 603 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000 604 default "8" 605 help 606 This allows you to specify the maximum number of CPUs which this 607 kernel will support. The maximum supported value is 4096 and the 608 minimum value which makes sense is 2. 609 610 This is purely to save memory - each supported CPU adds 611 approximately eight kilobytes to the kernel image. 612endif 613 614config SCHED_SMT 615 bool "SMT (Hyperthreading) scheduler support" 616 depends on X86_HT 617 help 618 SMT scheduler support improves the CPU scheduler's decision making 619 when dealing with Intel Pentium 4 chips with HyperThreading at a 620 cost of slightly increased overhead in some places. If unsure say 621 N here. 622 623config SCHED_MC 624 def_bool y 625 prompt "Multi-core scheduler support" 626 depends on X86_HT 627 help 628 Multi-core scheduler support improves the CPU scheduler's decision 629 making when dealing with multi-core CPU chips at a cost of slightly 630 increased overhead in some places. If unsure say N here. 631 632source "kernel/Kconfig.preempt" 633 634config X86_UP_APIC 635 bool "Local APIC support on uniprocessors" 636 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH) 637 help 638 A local APIC (Advanced Programmable Interrupt Controller) is an 639 integrated interrupt controller in the CPU. If you have a single-CPU 640 system which has a processor with a local APIC, you can say Y here to 641 enable and use it. If you say Y here even though your machine doesn't 642 have a local APIC, then the kernel will still run with no slowdown at 643 all. The local APIC supports CPU-generated self-interrupts (timer, 644 performance counters), and the NMI watchdog which detects hard 645 lockups. 646 647config X86_UP_IOAPIC 648 bool "IO-APIC support on uniprocessors" 649 depends on X86_UP_APIC 650 help 651 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 652 SMP-capable replacement for PC-style interrupt controllers. Most 653 SMP systems and many recent uniprocessor systems have one. 654 655 If you have a single-CPU system with an IO-APIC, you can say Y here 656 to use it. If you say Y here even though your machine doesn't have 657 an IO-APIC, then the kernel will still run with no slowdown at all. 658 659config X86_LOCAL_APIC 660 def_bool y 661 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH)) 662 663config X86_IO_APIC 664 def_bool y 665 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH)) 666 667config X86_VISWS_APIC 668 def_bool y 669 depends on X86_32 && X86_VISWS 670 671config X86_MCE 672 bool "Machine Check Exception" 673 depends on !X86_VOYAGER 674 ---help--- 675 Machine Check Exception support allows the processor to notify the 676 kernel if it detects a problem (e.g. overheating, component failure). 677 The action the kernel takes depends on the severity of the problem, 678 ranging from a warning message on the console, to halting the machine. 679 Your processor must be a Pentium or newer to support this - check the 680 flags in /proc/cpuinfo for mce. Note that some older Pentium systems 681 have a design flaw which leads to false MCE events - hence MCE is 682 disabled on all P5 processors, unless explicitly enabled with "mce" 683 as a boot argument. Similarly, if MCE is built in and creates a 684 problem on some new non-standard machine, you can boot with "nomce" 685 to disable it. MCE support simply ignores non-MCE processors like 686 the 386 and 486, so nearly everyone can say Y here. 687 688config X86_MCE_INTEL 689 def_bool y 690 prompt "Intel MCE features" 691 depends on X86_64 && X86_MCE && X86_LOCAL_APIC 692 help 693 Additional support for intel specific MCE features such as 694 the thermal monitor. 695 696config X86_MCE_AMD 697 def_bool y 698 prompt "AMD MCE features" 699 depends on X86_64 && X86_MCE && X86_LOCAL_APIC 700 help 701 Additional support for AMD specific MCE features such as 702 the DRAM Error Threshold. 703 704config X86_MCE_NONFATAL 705 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4" 706 depends on X86_32 && X86_MCE 707 help 708 Enabling this feature starts a timer that triggers every 5 seconds which 709 will look at the machine check registers to see if anything happened. 710 Non-fatal problems automatically get corrected (but still logged). 711 Disable this if you don't want to see these messages. 712 Seeing the messages this option prints out may be indicative of dying 713 or out-of-spec (ie, overclocked) hardware. 714 This option only does something on certain CPUs. 715 (AMD Athlon/Duron and Intel Pentium 4) 716 717config X86_MCE_P4THERMAL 718 bool "check for P4 thermal throttling interrupt." 719 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS 720 help 721 Enabling this feature will cause a message to be printed when the P4 722 enters thermal throttling. 723 724config VM86 725 bool "Enable VM86 support" if EMBEDDED 726 default y 727 depends on X86_32 728 help 729 This option is required by programs like DOSEMU to run 16-bit legacy 730 code on X86 processors. It also may be needed by software like 731 XFree86 to initialize some video cards via BIOS. Disabling this 732 option saves about 6k. 733 734config TOSHIBA 735 tristate "Toshiba Laptop support" 736 depends on X86_32 737 ---help--- 738 This adds a driver to safely access the System Management Mode of 739 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 740 not work on models with a Phoenix BIOS. The System Management Mode 741 is used to set the BIOS and power saving options on Toshiba portables. 742 743 For information on utilities to make use of this driver see the 744 Toshiba Linux utilities web site at: 745 <http://www.buzzard.org.uk/toshiba/>. 746 747 Say Y if you intend to run this kernel on a Toshiba portable. 748 Say N otherwise. 749 750config I8K 751 tristate "Dell laptop support" 752 ---help--- 753 This adds a driver to safely access the System Management Mode 754 of the CPU on the Dell Inspiron 8000. The System Management Mode 755 is used to read cpu temperature and cooling fan status and to 756 control the fans on the I8K portables. 757 758 This driver has been tested only on the Inspiron 8000 but it may 759 also work with other Dell laptops. You can force loading on other 760 models by passing the parameter `force=1' to the module. Use at 761 your own risk. 762 763 For information on utilities to make use of this driver see the 764 I8K Linux utilities web site at: 765 <http://people.debian.org/~dz/i8k/> 766 767 Say Y if you intend to run this kernel on a Dell Inspiron 8000. 768 Say N otherwise. 769 770config X86_REBOOTFIXUPS 771 def_bool n 772 prompt "Enable X86 board specific fixups for reboot" 773 depends on X86_32 && X86 774 ---help--- 775 This enables chipset and/or board specific fixups to be done 776 in order to get reboot to work correctly. This is only needed on 777 some combinations of hardware and BIOS. The symptom, for which 778 this config is intended, is when reboot ends with a stalled/hung 779 system. 780 781 Currently, the only fixup is for the Geode machines using 782 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 783 784 Say Y if you want to enable the fixup. Currently, it's safe to 785 enable this option even if you don't need it. 786 Say N otherwise. 787 788config MICROCODE 789 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support" 790 select FW_LOADER 791 ---help--- 792 If you say Y here, you will be able to update the microcode on 793 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II, 794 Pentium III, Pentium 4, Xeon etc. You will obviously need the 795 actual microcode binary data itself which is not shipped with the 796 Linux kernel. 797 798 For latest news and information on obtaining all the required 799 ingredients for this driver, check: 800 <http://www.urbanmyth.org/microcode/>. 801 802 To compile this driver as a module, choose M here: the 803 module will be called microcode. 804 805config MICROCODE_OLD_INTERFACE 806 def_bool y 807 depends on MICROCODE 808 809config X86_MSR 810 tristate "/dev/cpu/*/msr - Model-specific register support" 811 help 812 This device gives privileged processes access to the x86 813 Model-Specific Registers (MSRs). It is a character device with 814 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 815 MSR accesses are directed to a specific CPU on multi-processor 816 systems. 817 818config X86_CPUID 819 tristate "/dev/cpu/*/cpuid - CPU information support" 820 help 821 This device gives processes access to the x86 CPUID instruction to 822 be executed on a specific processor. It is a character device 823 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 824 /dev/cpu/31/cpuid. 825 826choice 827 prompt "High Memory Support" 828 default HIGHMEM4G if !X86_NUMAQ 829 default HIGHMEM64G if X86_NUMAQ 830 depends on X86_32 831 832config NOHIGHMEM 833 bool "off" 834 depends on !X86_NUMAQ 835 ---help--- 836 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 837 However, the address space of 32-bit x86 processors is only 4 838 Gigabytes large. That means that, if you have a large amount of 839 physical memory, not all of it can be "permanently mapped" by the 840 kernel. The physical memory that's not permanently mapped is called 841 "high memory". 842 843 If you are compiling a kernel which will never run on a machine with 844 more than 1 Gigabyte total physical RAM, answer "off" here (default 845 choice and suitable for most users). This will result in a "3GB/1GB" 846 split: 3GB are mapped so that each process sees a 3GB virtual memory 847 space and the remaining part of the 4GB virtual memory space is used 848 by the kernel to permanently map as much physical memory as 849 possible. 850 851 If the machine has between 1 and 4 Gigabytes physical RAM, then 852 answer "4GB" here. 853 854 If more than 4 Gigabytes is used then answer "64GB" here. This 855 selection turns Intel PAE (Physical Address Extension) mode on. 856 PAE implements 3-level paging on IA32 processors. PAE is fully 857 supported by Linux, PAE mode is implemented on all recent Intel 858 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 859 then the kernel will not boot on CPUs that don't support PAE! 860 861 The actual amount of total physical memory will either be 862 auto detected or can be forced by using a kernel command line option 863 such as "mem=256M". (Try "man bootparam" or see the documentation of 864 your boot loader (lilo or loadlin) about how to pass options to the 865 kernel at boot time.) 866 867 If unsure, say "off". 868 869config HIGHMEM4G 870 bool "4GB" 871 depends on !X86_NUMAQ 872 help 873 Select this if you have a 32-bit processor and between 1 and 4 874 gigabytes of physical RAM. 875 876config HIGHMEM64G 877 bool "64GB" 878 depends on !M386 && !M486 879 select X86_PAE 880 help 881 Select this if you have a 32-bit processor and more than 4 882 gigabytes of physical RAM. 883 884endchoice 885 886choice 887 depends on EXPERIMENTAL 888 prompt "Memory split" if EMBEDDED 889 default VMSPLIT_3G 890 depends on X86_32 891 help 892 Select the desired split between kernel and user memory. 893 894 If the address range available to the kernel is less than the 895 physical memory installed, the remaining memory will be available 896 as "high memory". Accessing high memory is a little more costly 897 than low memory, as it needs to be mapped into the kernel first. 898 Note that increasing the kernel address space limits the range 899 available to user programs, making the address space there 900 tighter. Selecting anything other than the default 3G/1G split 901 will also likely make your kernel incompatible with binary-only 902 kernel modules. 903 904 If you are not absolutely sure what you are doing, leave this 905 option alone! 906 907 config VMSPLIT_3G 908 bool "3G/1G user/kernel split" 909 config VMSPLIT_3G_OPT 910 depends on !X86_PAE 911 bool "3G/1G user/kernel split (for full 1G low memory)" 912 config VMSPLIT_2G 913 bool "2G/2G user/kernel split" 914 config VMSPLIT_2G_OPT 915 depends on !X86_PAE 916 bool "2G/2G user/kernel split (for full 2G low memory)" 917 config VMSPLIT_1G 918 bool "1G/3G user/kernel split" 919endchoice 920 921config PAGE_OFFSET 922 hex 923 default 0xB0000000 if VMSPLIT_3G_OPT 924 default 0x80000000 if VMSPLIT_2G 925 default 0x78000000 if VMSPLIT_2G_OPT 926 default 0x40000000 if VMSPLIT_1G 927 default 0xC0000000 928 depends on X86_32 929 930config HIGHMEM 931 def_bool y 932 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 933 934config X86_PAE 935 def_bool n 936 prompt "PAE (Physical Address Extension) Support" 937 depends on X86_32 && !HIGHMEM4G 938 select RESOURCES_64BIT 939 help 940 PAE is required for NX support, and furthermore enables 941 larger swapspace support for non-overcommit purposes. It 942 has the cost of more pagetable lookup overhead, and also 943 consumes more pagetable space per process. 944 945# Common NUMA Features 946config NUMA 947 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)" 948 depends on SMP 949 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL) 950 default n if X86_PC 951 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP) 952 help 953 Enable NUMA (Non Uniform Memory Access) support. 954 The kernel will try to allocate memory used by a CPU on the 955 local memory controller of the CPU and add some more 956 NUMA awareness to the kernel. 957 958 For i386 this is currently highly experimental and should be only 959 used for kernel development. It might also cause boot failures. 960 For x86_64 this is recommended on all multiprocessor Opteron systems. 961 If the system is EM64T, you should say N unless your system is 962 EM64T NUMA. 963 964comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI" 965 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI) 966 967config K8_NUMA 968 def_bool y 969 prompt "Old style AMD Opteron NUMA detection" 970 depends on X86_64 && NUMA && PCI 971 help 972 Enable K8 NUMA node topology detection. You should say Y here if 973 you have a multi processor AMD K8 system. This uses an old 974 method to read the NUMA configuration directly from the builtin 975 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA 976 instead, which also takes priority if both are compiled in. 977 978config X86_64_ACPI_NUMA 979 def_bool y 980 prompt "ACPI NUMA detection" 981 depends on X86_64 && NUMA && ACPI && PCI 982 select ACPI_NUMA 983 help 984 Enable ACPI SRAT based node topology detection. 985 986# Some NUMA nodes have memory ranges that span 987# other nodes. Even though a pfn is valid and 988# between a node's start and end pfns, it may not 989# reside on that node. See memmap_init_zone() 990# for details. 991config NODES_SPAN_OTHER_NODES 992 def_bool y 993 depends on X86_64_ACPI_NUMA 994 995config NUMA_EMU 996 bool "NUMA emulation" 997 depends on X86_64 && NUMA 998 help 999 Enable NUMA emulation. A flat machine will be split 1000 into virtual nodes when booted with "numa=fake=N", where N is the 1001 number of nodes. This is only useful for debugging. 1002 1003if MAXSMP 1004 1005config NODES_SHIFT 1006 int 1007 default "9" 1008endif 1009 1010if !MAXSMP 1011config NODES_SHIFT 1012 int "Maximum NUMA Nodes (as a power of 2)" 1013 range 1 9 if X86_64 1014 default "6" if X86_64 1015 default "4" if X86_NUMAQ 1016 default "3" 1017 depends on NEED_MULTIPLE_NODES 1018 help 1019 Specify the maximum number of NUMA Nodes available on the target 1020 system. Increases memory reserved to accomodate various tables. 1021endif 1022 1023config HAVE_ARCH_BOOTMEM_NODE 1024 def_bool y 1025 depends on X86_32 && NUMA 1026 1027config ARCH_HAVE_MEMORY_PRESENT 1028 def_bool y 1029 depends on X86_32 && DISCONTIGMEM 1030 1031config NEED_NODE_MEMMAP_SIZE 1032 def_bool y 1033 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1034 1035config HAVE_ARCH_ALLOC_REMAP 1036 def_bool y 1037 depends on X86_32 && NUMA 1038 1039config ARCH_FLATMEM_ENABLE 1040 def_bool y 1041 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA 1042 1043config ARCH_DISCONTIGMEM_ENABLE 1044 def_bool y 1045 depends on NUMA && X86_32 1046 1047config ARCH_DISCONTIGMEM_DEFAULT 1048 def_bool y 1049 depends on NUMA && X86_32 1050 1051config ARCH_SPARSEMEM_DEFAULT 1052 def_bool y 1053 depends on X86_64 1054 1055config ARCH_SPARSEMEM_ENABLE 1056 def_bool y 1057 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC) 1058 select SPARSEMEM_STATIC if X86_32 1059 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1060 1061config ARCH_SELECT_MEMORY_MODEL 1062 def_bool y 1063 depends on ARCH_SPARSEMEM_ENABLE 1064 1065config ARCH_MEMORY_PROBE 1066 def_bool X86_64 1067 depends on MEMORY_HOTPLUG 1068 1069source "mm/Kconfig" 1070 1071config HIGHPTE 1072 bool "Allocate 3rd-level pagetables from highmem" 1073 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G) 1074 help 1075 The VM uses one page table entry for each page of physical memory. 1076 For systems with a lot of RAM, this can be wasteful of precious 1077 low memory. Setting this option will put user-space page table 1078 entries in high memory. 1079 1080config MATH_EMULATION 1081 bool 1082 prompt "Math emulation" if X86_32 1083 ---help--- 1084 Linux can emulate a math coprocessor (used for floating point 1085 operations) if you don't have one. 486DX and Pentium processors have 1086 a math coprocessor built in, 486SX and 386 do not, unless you added 1087 a 487DX or 387, respectively. (The messages during boot time can 1088 give you some hints here ["man dmesg"].) Everyone needs either a 1089 coprocessor or this emulation. 1090 1091 If you don't have a math coprocessor, you need to say Y here; if you 1092 say Y here even though you have a coprocessor, the coprocessor will 1093 be used nevertheless. (This behavior can be changed with the kernel 1094 command line option "no387", which comes handy if your coprocessor 1095 is broken. Try "man bootparam" or see the documentation of your boot 1096 loader (lilo or loadlin) about how to pass options to the kernel at 1097 boot time.) This means that it is a good idea to say Y here if you 1098 intend to use this kernel on different machines. 1099 1100 More information about the internals of the Linux math coprocessor 1101 emulation can be found in <file:arch/x86/math-emu/README>. 1102 1103 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1104 kernel, it won't hurt. 1105 1106config MTRR 1107 bool "MTRR (Memory Type Range Register) support" 1108 ---help--- 1109 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1110 the Memory Type Range Registers (MTRRs) may be used to control 1111 processor access to memory ranges. This is most useful if you have 1112 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1113 allows bus write transfers to be combined into a larger transfer 1114 before bursting over the PCI/AGP bus. This can increase performance 1115 of image write operations 2.5 times or more. Saying Y here creates a 1116 /proc/mtrr file which may be used to manipulate your processor's 1117 MTRRs. Typically the X server should use this. 1118 1119 This code has a reasonably generic interface so that similar 1120 control registers on other processors can be easily supported 1121 as well: 1122 1123 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1124 Registers (ARRs) which provide a similar functionality to MTRRs. For 1125 these, the ARRs are used to emulate the MTRRs. 1126 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1127 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1128 write-combining. All of these processors are supported by this code 1129 and it makes sense to say Y here if you have one of them. 1130 1131 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1132 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1133 can lead to all sorts of problems, so it's good to say Y here. 1134 1135 You can safely say Y even if your machine doesn't have MTRRs, you'll 1136 just add about 9 KB to your kernel. 1137 1138 See <file:Documentation/mtrr.txt> for more information. 1139 1140config MTRR_SANITIZER 1141 def_bool y 1142 prompt "MTRR cleanup support" 1143 depends on MTRR 1144 help 1145 Convert MTRR layout from continuous to discrete, so some X driver 1146 could add WB entries. 1147 1148 Say N here if you see bootup problems (boot crash, boot hang, 1149 spontaneous reboots). 1150 1151 Could be disabled with disable_mtrr_cleanup. Also mtrr_chunk_size 1152 could be used to send largest mtrr entry size for continuous block 1153 to hold holes (aka. UC entries) 1154 1155 If unsure, say Y. 1156 1157config MTRR_SANITIZER_ENABLE_DEFAULT 1158 int "MTRR cleanup enable value (0-1)" 1159 range 0 1 1160 default "0" 1161 depends on MTRR_SANITIZER 1162 help 1163 Enable mtrr cleanup default value 1164 1165config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1166 int "MTRR cleanup spare reg num (0-7)" 1167 range 0 7 1168 default "1" 1169 depends on MTRR_SANITIZER 1170 help 1171 mtrr cleanup spare entries default, it can be changed via 1172 mtrr_spare_reg_nr= 1173 1174config X86_PAT 1175 bool 1176 prompt "x86 PAT support" 1177 depends on MTRR 1178 help 1179 Use PAT attributes to setup page level cache control. 1180 1181 PATs are the modern equivalents of MTRRs and are much more 1182 flexible than MTRRs. 1183 1184 Say N here if you see bootup problems (boot crash, boot hang, 1185 spontaneous reboots) or a non-working video driver. 1186 1187 If unsure, say Y. 1188 1189config EFI 1190 def_bool n 1191 prompt "EFI runtime service support" 1192 depends on ACPI 1193 ---help--- 1194 This enables the kernel to use EFI runtime services that are 1195 available (such as the EFI variable services). 1196 1197 This option is only useful on systems that have EFI firmware. 1198 In addition, you should use the latest ELILO loader available 1199 at <http://elilo.sourceforge.net> in order to take advantage 1200 of EFI runtime services. However, even with this option, the 1201 resultant kernel should continue to boot on existing non-EFI 1202 platforms. 1203 1204config IRQBALANCE 1205 def_bool y 1206 prompt "Enable kernel irq balancing" 1207 depends on X86_32 && SMP && X86_IO_APIC 1208 help 1209 The default yes will allow the kernel to do irq load balancing. 1210 Saying no will keep the kernel from doing irq load balancing. 1211 1212config SECCOMP 1213 def_bool y 1214 prompt "Enable seccomp to safely compute untrusted bytecode" 1215 depends on PROC_FS 1216 help 1217 This kernel feature is useful for number crunching applications 1218 that may need to compute untrusted bytecode during their 1219 execution. By using pipes or other transports made available to 1220 the process as file descriptors supporting the read/write 1221 syscalls, it's possible to isolate those applications in 1222 their own address space using seccomp. Once seccomp is 1223 enabled via /proc/<pid>/seccomp, it cannot be disabled 1224 and the task is only allowed to execute a few safe syscalls 1225 defined by each seccomp mode. 1226 1227 If unsure, say Y. Only embedded should say N here. 1228 1229config CC_STACKPROTECTOR 1230 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)" 1231 depends on X86_64 && EXPERIMENTAL && BROKEN 1232 help 1233 This option turns on the -fstack-protector GCC feature. This 1234 feature puts, at the beginning of critical functions, a canary 1235 value on the stack just before the return address, and validates 1236 the value just before actually returning. Stack based buffer 1237 overflows (that need to overwrite this return address) now also 1238 overwrite the canary, which gets detected and the attack is then 1239 neutralized via a kernel panic. 1240 1241 This feature requires gcc version 4.2 or above, or a distribution 1242 gcc with the feature backported. Older versions are automatically 1243 detected and for those versions, this configuration option is ignored. 1244 1245config CC_STACKPROTECTOR_ALL 1246 bool "Use stack-protector for all functions" 1247 depends on CC_STACKPROTECTOR 1248 help 1249 Normally, GCC only inserts the canary value protection for 1250 functions that use large-ish on-stack buffers. By enabling 1251 this option, GCC will be asked to do this for ALL functions. 1252 1253source kernel/Kconfig.hz 1254 1255config KEXEC 1256 bool "kexec system call" 1257 depends on X86_BIOS_REBOOT 1258 help 1259 kexec is a system call that implements the ability to shutdown your 1260 current kernel, and to start another kernel. It is like a reboot 1261 but it is independent of the system firmware. And like a reboot 1262 you can start any kernel with it, not just Linux. 1263 1264 The name comes from the similarity to the exec system call. 1265 1266 It is an ongoing process to be certain the hardware in a machine 1267 is properly shutdown, so do not be surprised if this code does not 1268 initially work for you. It may help to enable device hotplugging 1269 support. As of this writing the exact hardware interface is 1270 strongly in flux, so no good recommendation can be made. 1271 1272config CRASH_DUMP 1273 bool "kernel crash dumps (EXPERIMENTAL)" 1274 depends on X86_64 || (X86_32 && HIGHMEM) 1275 help 1276 Generate crash dump after being started by kexec. 1277 This should be normally only set in special crash dump kernels 1278 which are loaded in the main kernel with kexec-tools into 1279 a specially reserved region and then later executed after 1280 a crash by kdump/kexec. The crash dump kernel must be compiled 1281 to a memory address not used by the main kernel or BIOS using 1282 PHYSICAL_START, or it must be built as a relocatable image 1283 (CONFIG_RELOCATABLE=y). 1284 For more details see Documentation/kdump/kdump.txt 1285 1286config PHYSICAL_START 1287 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP) 1288 default "0x1000000" if X86_NUMAQ 1289 default "0x200000" if X86_64 1290 default "0x100000" 1291 help 1292 This gives the physical address where the kernel is loaded. 1293 1294 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1295 bzImage will decompress itself to above physical address and 1296 run from there. Otherwise, bzImage will run from the address where 1297 it has been loaded by the boot loader and will ignore above physical 1298 address. 1299 1300 In normal kdump cases one does not have to set/change this option 1301 as now bzImage can be compiled as a completely relocatable image 1302 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1303 address. This option is mainly useful for the folks who don't want 1304 to use a bzImage for capturing the crash dump and want to use a 1305 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1306 to be specifically compiled to run from a specific memory area 1307 (normally a reserved region) and this option comes handy. 1308 1309 So if you are using bzImage for capturing the crash dump, leave 1310 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y. 1311 Otherwise if you plan to use vmlinux for capturing the crash dump 1312 change this value to start of the reserved region (Typically 16MB 1313 0x1000000). In other words, it can be set based on the "X" value as 1314 specified in the "crashkernel=YM@XM" command line boot parameter 1315 passed to the panic-ed kernel. Typically this parameter is set as 1316 crashkernel=64M@16M. Please take a look at 1317 Documentation/kdump/kdump.txt for more details about crash dumps. 1318 1319 Usage of bzImage for capturing the crash dump is recommended as 1320 one does not have to build two kernels. Same kernel can be used 1321 as production kernel and capture kernel. Above option should have 1322 gone away after relocatable bzImage support is introduced. But it 1323 is present because there are users out there who continue to use 1324 vmlinux for dump capture. This option should go away down the 1325 line. 1326 1327 Don't change this unless you know what you are doing. 1328 1329config RELOCATABLE 1330 bool "Build a relocatable kernel (EXPERIMENTAL)" 1331 depends on EXPERIMENTAL 1332 help 1333 This builds a kernel image that retains relocation information 1334 so it can be loaded someplace besides the default 1MB. 1335 The relocations tend to make the kernel binary about 10% larger, 1336 but are discarded at runtime. 1337 1338 One use is for the kexec on panic case where the recovery kernel 1339 must live at a different physical address than the primary 1340 kernel. 1341 1342 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1343 it has been loaded at and the compile time physical address 1344 (CONFIG_PHYSICAL_START) is ignored. 1345 1346config PHYSICAL_ALIGN 1347 hex 1348 prompt "Alignment value to which kernel should be aligned" if X86_32 1349 default "0x100000" if X86_32 1350 default "0x200000" if X86_64 1351 range 0x2000 0x400000 1352 help 1353 This value puts the alignment restrictions on physical address 1354 where kernel is loaded and run from. Kernel is compiled for an 1355 address which meets above alignment restriction. 1356 1357 If bootloader loads the kernel at a non-aligned address and 1358 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1359 address aligned to above value and run from there. 1360 1361 If bootloader loads the kernel at a non-aligned address and 1362 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1363 load address and decompress itself to the address it has been 1364 compiled for and run from there. The address for which kernel is 1365 compiled already meets above alignment restrictions. Hence the 1366 end result is that kernel runs from a physical address meeting 1367 above alignment restrictions. 1368 1369 Don't change this unless you know what you are doing. 1370 1371config HOTPLUG_CPU 1372 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)" 1373 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER 1374 ---help--- 1375 Say Y here to experiment with turning CPUs off and on, and to 1376 enable suspend on SMP systems. CPUs can be controlled through 1377 /sys/devices/system/cpu. 1378 Say N if you want to disable CPU hotplug and don't need to 1379 suspend. 1380 1381config COMPAT_VDSO 1382 def_bool y 1383 prompt "Compat VDSO support" 1384 depends on X86_32 || IA32_EMULATION 1385 help 1386 Map the 32-bit VDSO to the predictable old-style address too. 1387 ---help--- 1388 Say N here if you are running a sufficiently recent glibc 1389 version (2.3.3 or later), to remove the high-mapped 1390 VDSO mapping and to exclusively use the randomized VDSO. 1391 1392 If unsure, say Y. 1393 1394endmenu 1395 1396config ARCH_ENABLE_MEMORY_HOTPLUG 1397 def_bool y 1398 depends on X86_64 || (X86_32 && HIGHMEM) 1399 1400config HAVE_ARCH_EARLY_PFN_TO_NID 1401 def_bool X86_64 1402 depends on NUMA 1403 1404menu "Power management options" 1405 depends on !X86_VOYAGER 1406 1407config ARCH_HIBERNATION_HEADER 1408 def_bool y 1409 depends on X86_64 && HIBERNATION 1410 1411source "kernel/power/Kconfig" 1412 1413source "drivers/acpi/Kconfig" 1414 1415config X86_APM_BOOT 1416 bool 1417 default y 1418 depends on APM || APM_MODULE 1419 1420menuconfig APM 1421 tristate "APM (Advanced Power Management) BIOS support" 1422 depends on X86_32 && PM_SLEEP && !X86_VISWS 1423 ---help--- 1424 APM is a BIOS specification for saving power using several different 1425 techniques. This is mostly useful for battery powered laptops with 1426 APM compliant BIOSes. If you say Y here, the system time will be 1427 reset after a RESUME operation, the /proc/apm device will provide 1428 battery status information, and user-space programs will receive 1429 notification of APM "events" (e.g. battery status change). 1430 1431 If you select "Y" here, you can disable actual use of the APM 1432 BIOS by passing the "apm=off" option to the kernel at boot time. 1433 1434 Note that the APM support is almost completely disabled for 1435 machines with more than one CPU. 1436 1437 In order to use APM, you will need supporting software. For location 1438 and more information, read <file:Documentation/power/pm.txt> and the 1439 Battery Powered Linux mini-HOWTO, available from 1440 <http://www.tldp.org/docs.html#howto>. 1441 1442 This driver does not spin down disk drives (see the hdparm(8) 1443 manpage ("man 8 hdparm") for that), and it doesn't turn off 1444 VESA-compliant "green" monitors. 1445 1446 This driver does not support the TI 4000M TravelMate and the ACER 1447 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1448 desktop machines also don't have compliant BIOSes, and this driver 1449 may cause those machines to panic during the boot phase. 1450 1451 Generally, if you don't have a battery in your machine, there isn't 1452 much point in using this driver and you should say N. If you get 1453 random kernel OOPSes or reboots that don't seem to be related to 1454 anything, try disabling/enabling this option (or disabling/enabling 1455 APM in your BIOS). 1456 1457 Some other things you should try when experiencing seemingly random, 1458 "weird" problems: 1459 1460 1) make sure that you have enough swap space and that it is 1461 enabled. 1462 2) pass the "no-hlt" option to the kernel 1463 3) switch on floating point emulation in the kernel and pass 1464 the "no387" option to the kernel 1465 4) pass the "floppy=nodma" option to the kernel 1466 5) pass the "mem=4M" option to the kernel (thereby disabling 1467 all but the first 4 MB of RAM) 1468 6) make sure that the CPU is not over clocked. 1469 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1470 8) disable the cache from your BIOS settings 1471 9) install a fan for the video card or exchange video RAM 1472 10) install a better fan for the CPU 1473 11) exchange RAM chips 1474 12) exchange the motherboard. 1475 1476 To compile this driver as a module, choose M here: the 1477 module will be called apm. 1478 1479if APM 1480 1481config APM_IGNORE_USER_SUSPEND 1482 bool "Ignore USER SUSPEND" 1483 help 1484 This option will ignore USER SUSPEND requests. On machines with a 1485 compliant APM BIOS, you want to say N. However, on the NEC Versa M 1486 series notebooks, it is necessary to say Y because of a BIOS bug. 1487 1488config APM_DO_ENABLE 1489 bool "Enable PM at boot time" 1490 ---help--- 1491 Enable APM features at boot time. From page 36 of the APM BIOS 1492 specification: "When disabled, the APM BIOS does not automatically 1493 power manage devices, enter the Standby State, enter the Suspend 1494 State, or take power saving steps in response to CPU Idle calls." 1495 This driver will make CPU Idle calls when Linux is idle (unless this 1496 feature is turned off -- see "Do CPU IDLE calls", below). This 1497 should always save battery power, but more complicated APM features 1498 will be dependent on your BIOS implementation. You may need to turn 1499 this option off if your computer hangs at boot time when using APM 1500 support, or if it beeps continuously instead of suspending. Turn 1501 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1502 T400CDT. This is off by default since most machines do fine without 1503 this feature. 1504 1505config APM_CPU_IDLE 1506 bool "Make CPU Idle calls when idle" 1507 help 1508 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 1509 On some machines, this can activate improved power savings, such as 1510 a slowed CPU clock rate, when the machine is idle. These idle calls 1511 are made after the idle loop has run for some length of time (e.g., 1512 333 mS). On some machines, this will cause a hang at boot time or 1513 whenever the CPU becomes idle. (On machines with more than one CPU, 1514 this option does nothing.) 1515 1516config APM_DISPLAY_BLANK 1517 bool "Enable console blanking using APM" 1518 help 1519 Enable console blanking using the APM. Some laptops can use this to 1520 turn off the LCD backlight when the screen blanker of the Linux 1521 virtual console blanks the screen. Note that this is only used by 1522 the virtual console screen blanker, and won't turn off the backlight 1523 when using the X Window system. This also doesn't have anything to 1524 do with your VESA-compliant power-saving monitor. Further, this 1525 option doesn't work for all laptops -- it might not turn off your 1526 backlight at all, or it might print a lot of errors to the console, 1527 especially if you are using gpm. 1528 1529config APM_ALLOW_INTS 1530 bool "Allow interrupts during APM BIOS calls" 1531 help 1532 Normally we disable external interrupts while we are making calls to 1533 the APM BIOS as a measure to lessen the effects of a badly behaving 1534 BIOS implementation. The BIOS should reenable interrupts if it 1535 needs to. Unfortunately, some BIOSes do not -- especially those in 1536 many of the newer IBM Thinkpads. If you experience hangs when you 1537 suspend, try setting this to Y. Otherwise, say N. 1538 1539config APM_REAL_MODE_POWER_OFF 1540 bool "Use real mode APM BIOS call to power off" 1541 help 1542 Use real mode APM BIOS calls to switch off the computer. This is 1543 a work-around for a number of buggy BIOSes. Switch this option on if 1544 your computer crashes instead of powering off properly. 1545 1546endif # APM 1547 1548source "arch/x86/kernel/cpu/cpufreq/Kconfig" 1549 1550source "drivers/cpuidle/Kconfig" 1551 1552endmenu 1553 1554 1555menu "Bus options (PCI etc.)" 1556 1557config PCI 1558 bool "PCI support" 1559 default y 1560 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC) 1561 help 1562 Find out whether you have a PCI motherboard. PCI is the name of a 1563 bus system, i.e. the way the CPU talks to the other stuff inside 1564 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 1565 VESA. If you have PCI, say Y, otherwise N. 1566 1567choice 1568 prompt "PCI access mode" 1569 depends on X86_32 && PCI && !X86_VISWS 1570 default PCI_GOANY 1571 ---help--- 1572 On PCI systems, the BIOS can be used to detect the PCI devices and 1573 determine their configuration. However, some old PCI motherboards 1574 have BIOS bugs and may crash if this is done. Also, some embedded 1575 PCI-based systems don't have any BIOS at all. Linux can also try to 1576 detect the PCI hardware directly without using the BIOS. 1577 1578 With this option, you can specify how Linux should detect the 1579 PCI devices. If you choose "BIOS", the BIOS will be used, 1580 if you choose "Direct", the BIOS won't be used, and if you 1581 choose "MMConfig", then PCI Express MMCONFIG will be used. 1582 If you choose "Any", the kernel will try MMCONFIG, then the 1583 direct access method and falls back to the BIOS if that doesn't 1584 work. If unsure, go with the default, which is "Any". 1585 1586config PCI_GOBIOS 1587 bool "BIOS" 1588 1589config PCI_GOMMCONFIG 1590 bool "MMConfig" 1591 1592config PCI_GODIRECT 1593 bool "Direct" 1594 1595config PCI_GOOLPC 1596 bool "OLPC" 1597 depends on OLPC 1598 1599config PCI_GOANY 1600 bool "Any" 1601 1602endchoice 1603 1604config PCI_BIOS 1605 def_bool y 1606 depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY) 1607 1608# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 1609config PCI_DIRECT 1610 def_bool y 1611 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC) || X86_VISWS) 1612 1613config PCI_MMCONFIG 1614 def_bool y 1615 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY) 1616 1617config PCI_OLPC 1618 def_bool y 1619 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 1620 1621config PCI_DOMAINS 1622 def_bool y 1623 depends on PCI 1624 1625config PCI_MMCONFIG 1626 bool "Support mmconfig PCI config space access" 1627 depends on X86_64 && PCI && ACPI 1628 1629config DMAR 1630 bool "Support for DMA Remapping Devices (EXPERIMENTAL)" 1631 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL 1632 help 1633 DMA remapping (DMAR) devices support enables independent address 1634 translations for Direct Memory Access (DMA) from devices. 1635 These DMA remapping devices are reported via ACPI tables 1636 and include PCI device scope covered by these DMA 1637 remapping devices. 1638 1639config DMAR_GFX_WA 1640 def_bool y 1641 prompt "Support for Graphics workaround" 1642 depends on DMAR 1643 help 1644 Current Graphics drivers tend to use physical address 1645 for DMA and avoid using DMA APIs. Setting this config 1646 option permits the IOMMU driver to set a unity map for 1647 all the OS-visible memory. Hence the driver can continue 1648 to use physical addresses for DMA. 1649 1650config DMAR_FLOPPY_WA 1651 def_bool y 1652 depends on DMAR 1653 help 1654 Floppy disk drivers are know to bypass DMA API calls 1655 thereby failing to work when IOMMU is enabled. This 1656 workaround will setup a 1:1 mapping for the first 1657 16M to make floppy (an ISA device) work. 1658 1659source "drivers/pci/pcie/Kconfig" 1660 1661source "drivers/pci/Kconfig" 1662 1663# x86_64 have no ISA slots, but do have ISA-style DMA. 1664config ISA_DMA_API 1665 def_bool y 1666 1667if X86_32 1668 1669config ISA 1670 bool "ISA support" 1671 depends on !(X86_VOYAGER || X86_VISWS) 1672 help 1673 Find out whether you have ISA slots on your motherboard. ISA is the 1674 name of a bus system, i.e. the way the CPU talks to the other stuff 1675 inside your box. Other bus systems are PCI, EISA, MicroChannel 1676 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 1677 newer boards don't support it. If you have ISA, say Y, otherwise N. 1678 1679config EISA 1680 bool "EISA support" 1681 depends on ISA 1682 ---help--- 1683 The Extended Industry Standard Architecture (EISA) bus was 1684 developed as an open alternative to the IBM MicroChannel bus. 1685 1686 The EISA bus provided some of the features of the IBM MicroChannel 1687 bus while maintaining backward compatibility with cards made for 1688 the older ISA bus. The EISA bus saw limited use between 1988 and 1689 1995 when it was made obsolete by the PCI bus. 1690 1691 Say Y here if you are building a kernel for an EISA-based machine. 1692 1693 Otherwise, say N. 1694 1695source "drivers/eisa/Kconfig" 1696 1697config MCA 1698 bool "MCA support" if !(X86_VISWS || X86_VOYAGER) 1699 default y if X86_VOYAGER 1700 help 1701 MicroChannel Architecture is found in some IBM PS/2 machines and 1702 laptops. It is a bus system similar to PCI or ISA. See 1703 <file:Documentation/mca.txt> (and especially the web page given 1704 there) before attempting to build an MCA bus kernel. 1705 1706source "drivers/mca/Kconfig" 1707 1708config SCx200 1709 tristate "NatSemi SCx200 support" 1710 depends on !X86_VOYAGER 1711 help 1712 This provides basic support for National Semiconductor's 1713 (now AMD's) Geode processors. The driver probes for the 1714 PCI-IDs of several on-chip devices, so its a good dependency 1715 for other scx200_* drivers. 1716 1717 If compiled as a module, the driver is named scx200. 1718 1719config SCx200HR_TIMER 1720 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 1721 depends on SCx200 && GENERIC_TIME 1722 default y 1723 help 1724 This driver provides a clocksource built upon the on-chip 1725 27MHz high-resolution timer. Its also a workaround for 1726 NSC Geode SC-1100's buggy TSC, which loses time when the 1727 processor goes idle (as is done by the scheduler). The 1728 other workaround is idle=poll boot option. 1729 1730config GEODE_MFGPT_TIMER 1731 def_bool y 1732 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events" 1733 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS 1734 help 1735 This driver provides a clock event source based on the MFGPT 1736 timer(s) in the CS5535 and CS5536 companion chip for the geode. 1737 MFGPTs have a better resolution and max interval than the 1738 generic PIT, and are suitable for use as high-res timers. 1739 1740config OLPC 1741 bool "One Laptop Per Child support" 1742 default n 1743 help 1744 Add support for detecting the unique features of the OLPC 1745 XO hardware. 1746 1747endif # X86_32 1748 1749config K8_NB 1750 def_bool y 1751 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA))) 1752 1753source "drivers/pcmcia/Kconfig" 1754 1755source "drivers/pci/hotplug/Kconfig" 1756 1757endmenu 1758 1759 1760menu "Executable file formats / Emulations" 1761 1762source "fs/Kconfig.binfmt" 1763 1764config IA32_EMULATION 1765 bool "IA32 Emulation" 1766 depends on X86_64 1767 select COMPAT_BINFMT_ELF 1768 help 1769 Include code to run 32-bit programs under a 64-bit kernel. You should 1770 likely turn this on, unless you're 100% sure that you don't have any 1771 32-bit programs left. 1772 1773config IA32_AOUT 1774 tristate "IA32 a.out support" 1775 depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT 1776 help 1777 Support old a.out binaries in the 32bit emulation. 1778 1779config COMPAT 1780 def_bool y 1781 depends on IA32_EMULATION 1782 1783config COMPAT_FOR_U64_ALIGNMENT 1784 def_bool COMPAT 1785 depends on X86_64 1786 1787config SYSVIPC_COMPAT 1788 def_bool y 1789 depends on X86_64 && COMPAT && SYSVIPC 1790 1791endmenu 1792 1793 1794source "net/Kconfig" 1795 1796source "drivers/Kconfig" 1797 1798source "drivers/firmware/Kconfig" 1799 1800source "fs/Kconfig" 1801 1802source "arch/x86/Kconfig.debug" 1803 1804source "security/Kconfig" 1805 1806source "crypto/Kconfig" 1807 1808source "arch/x86/kvm/Kconfig" 1809 1810source "lib/Kconfig" 1811