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_IOREMAP_PROT 25 select HAVE_GET_USER_PAGES_FAST 26 select HAVE_KPROBES 27 select ARCH_WANT_OPTIONAL_GPIOLIB 28 select HAVE_KRETPROBES 29 select HAVE_DYNAMIC_FTRACE 30 select HAVE_FTRACE 31 select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64) 32 select HAVE_ARCH_KGDB if !X86_VOYAGER 33 select HAVE_EFFICIENT_UNALIGNED_ACCESS 34 35config ARCH_DEFCONFIG 36 string 37 default "arch/x86/configs/i386_defconfig" if X86_32 38 default "arch/x86/configs/x86_64_defconfig" if X86_64 39 40 41config GENERIC_LOCKBREAK 42 def_bool n 43 44config GENERIC_TIME 45 def_bool y 46 47config GENERIC_CMOS_UPDATE 48 def_bool y 49 50config CLOCKSOURCE_WATCHDOG 51 def_bool y 52 53config GENERIC_CLOCKEVENTS 54 def_bool y 55 56config GENERIC_CLOCKEVENTS_BROADCAST 57 def_bool y 58 depends on X86_64 || (X86_32 && X86_LOCAL_APIC) 59 60config LOCKDEP_SUPPORT 61 def_bool y 62 63config STACKTRACE_SUPPORT 64 def_bool y 65 66config HAVE_LATENCYTOP_SUPPORT 67 def_bool y 68 69config FAST_CMPXCHG_LOCAL 70 bool 71 default y 72 73config MMU 74 def_bool y 75 76config ZONE_DMA 77 def_bool y 78 79config SBUS 80 bool 81 82config GENERIC_ISA_DMA 83 def_bool y 84 85config GENERIC_IOMAP 86 def_bool y 87 88config GENERIC_BUG 89 def_bool y 90 depends on BUG 91 92config GENERIC_HWEIGHT 93 def_bool y 94 95config GENERIC_GPIO 96 def_bool n 97 98config ARCH_MAY_HAVE_PC_FDC 99 def_bool y 100 101config RWSEM_GENERIC_SPINLOCK 102 def_bool !X86_XADD 103 104config RWSEM_XCHGADD_ALGORITHM 105 def_bool X86_XADD 106 107config ARCH_HAS_ILOG2_U32 108 def_bool n 109 110config ARCH_HAS_ILOG2_U64 111 def_bool n 112 113config ARCH_HAS_CPU_IDLE_WAIT 114 def_bool y 115 116config GENERIC_CALIBRATE_DELAY 117 def_bool y 118 119config GENERIC_TIME_VSYSCALL 120 bool 121 default X86_64 122 123config ARCH_HAS_CPU_RELAX 124 def_bool y 125 126config ARCH_HAS_CACHE_LINE_SIZE 127 def_bool y 128 129config HAVE_SETUP_PER_CPU_AREA 130 def_bool X86_64_SMP || (X86_SMP && !X86_VOYAGER) 131 132config HAVE_CPUMASK_OF_CPU_MAP 133 def_bool X86_64_SMP 134 135config ARCH_HIBERNATION_POSSIBLE 136 def_bool y 137 depends on !SMP || !X86_VOYAGER 138 139config ARCH_SUSPEND_POSSIBLE 140 def_bool y 141 depends on !X86_VOYAGER 142 143config ZONE_DMA32 144 bool 145 default X86_64 146 147config ARCH_POPULATES_NODE_MAP 148 def_bool y 149 150config AUDIT_ARCH 151 bool 152 default X86_64 153 154config ARCH_SUPPORTS_AOUT 155 def_bool y 156 157config ARCH_SUPPORTS_OPTIMIZED_INLINING 158 def_bool y 159 160# Use the generic interrupt handling code in kernel/irq/: 161config GENERIC_HARDIRQS 162 bool 163 default y 164 165config GENERIC_IRQ_PROBE 166 bool 167 default y 168 169config GENERIC_PENDING_IRQ 170 bool 171 depends on GENERIC_HARDIRQS && SMP 172 default y 173 174config X86_SMP 175 bool 176 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64) 177 select USE_GENERIC_SMP_HELPERS 178 default y 179 180config X86_32_SMP 181 def_bool y 182 depends on X86_32 && SMP 183 184config X86_64_SMP 185 def_bool y 186 depends on X86_64 && SMP 187 188config X86_HT 189 bool 190 depends on SMP 191 depends on (X86_32 && !X86_VOYAGER) || X86_64 192 default y 193 194config X86_BIOS_REBOOT 195 bool 196 depends on !X86_VOYAGER 197 default y 198 199config X86_TRAMPOLINE 200 bool 201 depends on X86_SMP || (X86_VOYAGER && SMP) || (64BIT && ACPI_SLEEP) 202 default y 203 204config KTIME_SCALAR 205 def_bool X86_32 206source "init/Kconfig" 207 208menu "Processor type and features" 209 210source "kernel/time/Kconfig" 211 212config SMP 213 bool "Symmetric multi-processing support" 214 ---help--- 215 This enables support for systems with more than one CPU. If you have 216 a system with only one CPU, like most personal computers, say N. If 217 you have a system with more than one CPU, say Y. 218 219 If you say N here, the kernel will run on single and multiprocessor 220 machines, but will use only one CPU of a multiprocessor machine. If 221 you say Y here, the kernel will run on many, but not all, 222 singleprocessor machines. On a singleprocessor machine, the kernel 223 will run faster if you say N here. 224 225 Note that if you say Y here and choose architecture "586" or 226 "Pentium" under "Processor family", the kernel will not work on 486 227 architectures. Similarly, multiprocessor kernels for the "PPro" 228 architecture may not work on all Pentium based boards. 229 230 People using multiprocessor machines who say Y here should also say 231 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 232 Management" code will be disabled if you say Y here. 233 234 See also <file:Documentation/i386/IO-APIC.txt>, 235 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 236 <http://www.tldp.org/docs.html#howto>. 237 238 If you don't know what to do here, say N. 239 240config X86_FIND_SMP_CONFIG 241 def_bool y 242 depends on X86_MPPARSE || X86_VOYAGER 243 244if ACPI 245config X86_MPPARSE 246 def_bool y 247 bool "Enable MPS table" 248 depends on X86_LOCAL_APIC 249 help 250 For old smp systems that do not have proper acpi support. Newer systems 251 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 252endif 253 254if !ACPI 255config X86_MPPARSE 256 def_bool y 257 depends on X86_LOCAL_APIC 258endif 259 260choice 261 prompt "Subarchitecture Type" 262 default X86_PC 263 264config X86_PC 265 bool "PC-compatible" 266 help 267 Choose this option if your computer is a standard PC or compatible. 268 269config X86_ELAN 270 bool "AMD Elan" 271 depends on X86_32 272 help 273 Select this for an AMD Elan processor. 274 275 Do not use this option for K6/Athlon/Opteron processors! 276 277 If unsure, choose "PC-compatible" instead. 278 279config X86_VOYAGER 280 bool "Voyager (NCR)" 281 depends on X86_32 && (SMP || BROKEN) && !PCI 282 help 283 Voyager is an MCA-based 32-way capable SMP architecture proprietary 284 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based. 285 286 *** WARNING *** 287 288 If you do not specifically know you have a Voyager based machine, 289 say N here, otherwise the kernel you build will not be bootable. 290 291config X86_GENERICARCH 292 bool "Generic architecture" 293 depends on X86_32 294 help 295 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default 296 subarchitectures. It is intended for a generic binary kernel. 297 if you select them all, kernel will probe it one by one. and will 298 fallback to default. 299 300if X86_GENERICARCH 301 302config X86_NUMAQ 303 bool "NUMAQ (IBM/Sequent)" 304 depends on SMP && X86_32 && PCI && X86_MPPARSE 305 select NUMA 306 help 307 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent) 308 NUMA multiquad box. This changes the way that processors are 309 bootstrapped, and uses Clustered Logical APIC addressing mode instead 310 of Flat Logical. You will need a new lynxer.elf file to flash your 311 firmware with - send email to <Martin.Bligh@us.ibm.com>. 312 313config X86_SUMMIT 314 bool "Summit/EXA (IBM x440)" 315 depends on X86_32 && SMP 316 help 317 This option is needed for IBM systems that use the Summit/EXA chipset. 318 In particular, it is needed for the x440. 319 320config X86_ES7000 321 bool "Support for Unisys ES7000 IA32 series" 322 depends on X86_32 && SMP 323 help 324 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is 325 supposed to run on an IA32-based Unisys ES7000 system. 326 327config X86_BIGSMP 328 bool "Support for big SMP systems with more than 8 CPUs" 329 depends on X86_32 && SMP 330 help 331 This option is needed for the systems that have more than 8 CPUs 332 and if the system is not of any sub-arch type above. 333 334endif 335 336config X86_VSMP 337 bool "Support for ScaleMP vSMP" 338 select PARAVIRT 339 depends on X86_64 && PCI 340 help 341 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 342 supposed to run on these EM64T-based machines. Only choose this option 343 if you have one of these machines. 344 345endchoice 346 347config X86_VISWS 348 bool "SGI 320/540 (Visual Workstation)" 349 depends on X86_32 && PCI && !X86_VOYAGER && X86_MPPARSE && PCI_GODIRECT 350 help 351 The SGI Visual Workstation series is an IA32-based workstation 352 based on SGI systems chips with some legacy PC hardware attached. 353 354 Say Y here to create a kernel to run on the SGI 320 or 540. 355 356 A kernel compiled for the Visual Workstation will run on general 357 PCs as well. See <file:Documentation/sgi-visws.txt> for details. 358 359config X86_RDC321X 360 bool "RDC R-321x SoC" 361 depends on X86_32 362 select M486 363 select X86_REBOOTFIXUPS 364 help 365 This option is needed for RDC R-321x system-on-chip, also known 366 as R-8610-(G). 367 If you don't have one of these chips, you should say N here. 368 369config SCHED_NO_NO_OMIT_FRAME_POINTER 370 def_bool y 371 prompt "Single-depth WCHAN output" 372 depends on X86_32 373 help 374 Calculate simpler /proc/<PID>/wchan values. If this option 375 is disabled then wchan values will recurse back to the 376 caller function. This provides more accurate wchan values, 377 at the expense of slightly more scheduling overhead. 378 379 If in doubt, say "Y". 380 381menuconfig PARAVIRT_GUEST 382 bool "Paravirtualized guest support" 383 help 384 Say Y here to get to see options related to running Linux under 385 various hypervisors. This option alone does not add any kernel code. 386 387 If you say N, all options in this submenu will be skipped and disabled. 388 389if PARAVIRT_GUEST 390 391source "arch/x86/xen/Kconfig" 392 393config VMI 394 bool "VMI Guest support" 395 select PARAVIRT 396 depends on X86_32 397 depends on !X86_VOYAGER 398 help 399 VMI provides a paravirtualized interface to the VMware ESX server 400 (it could be used by other hypervisors in theory too, but is not 401 at the moment), by linking the kernel to a GPL-ed ROM module 402 provided by the hypervisor. 403 404config KVM_CLOCK 405 bool "KVM paravirtualized clock" 406 select PARAVIRT 407 select PARAVIRT_CLOCK 408 depends on !X86_VOYAGER 409 help 410 Turning on this option will allow you to run a paravirtualized clock 411 when running over the KVM hypervisor. Instead of relying on a PIT 412 (or probably other) emulation by the underlying device model, the host 413 provides the guest with timing infrastructure such as time of day, and 414 system time 415 416config KVM_GUEST 417 bool "KVM Guest support" 418 select PARAVIRT 419 depends on !X86_VOYAGER 420 help 421 This option enables various optimizations for running under the KVM 422 hypervisor. 423 424source "arch/x86/lguest/Kconfig" 425 426config PARAVIRT 427 bool "Enable paravirtualization code" 428 depends on !X86_VOYAGER 429 help 430 This changes the kernel so it can modify itself when it is run 431 under a hypervisor, potentially improving performance significantly 432 over full virtualization. However, when run without a hypervisor 433 the kernel is theoretically slower and slightly larger. 434 435config PARAVIRT_CLOCK 436 bool 437 default n 438 439endif 440 441config PARAVIRT_DEBUG 442 bool "paravirt-ops debugging" 443 depends on PARAVIRT && DEBUG_KERNEL 444 help 445 Enable to debug paravirt_ops internals. Specifically, BUG if 446 a paravirt_op is missing when it is called. 447 448config MEMTEST 449 bool "Memtest" 450 help 451 This option adds a kernel parameter 'memtest', which allows memtest 452 to be set. 453 memtest=0, mean disabled; -- default 454 memtest=1, mean do 1 test pattern; 455 ... 456 memtest=4, mean do 4 test patterns. 457 If you are unsure how to answer this question, answer N. 458 459config X86_SUMMIT_NUMA 460 def_bool y 461 depends on X86_32 && NUMA && X86_GENERICARCH 462 463config X86_CYCLONE_TIMER 464 def_bool y 465 depends on X86_GENERICARCH 466 467config ES7000_CLUSTERED_APIC 468 def_bool y 469 depends on SMP && X86_ES7000 && MPENTIUMIII 470 471source "arch/x86/Kconfig.cpu" 472 473config HPET_TIMER 474 def_bool X86_64 475 prompt "HPET Timer Support" if X86_32 476 help 477 Use the IA-PC HPET (High Precision Event Timer) to manage 478 time in preference to the PIT and RTC, if a HPET is 479 present. 480 HPET is the next generation timer replacing legacy 8254s. 481 The HPET provides a stable time base on SMP 482 systems, unlike the TSC, but it is more expensive to access, 483 as it is off-chip. You can find the HPET spec at 484 <http://www.intel.com/hardwaredesign/hpetspec.htm>. 485 486 You can safely choose Y here. However, HPET will only be 487 activated if the platform and the BIOS support this feature. 488 Otherwise the 8254 will be used for timing services. 489 490 Choose N to continue using the legacy 8254 timer. 491 492config HPET_EMULATE_RTC 493 def_bool y 494 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 495 496# Mark as embedded because too many people got it wrong. 497# The code disables itself when not needed. 498config DMI 499 default y 500 bool "Enable DMI scanning" if EMBEDDED 501 help 502 Enabled scanning of DMI to identify machine quirks. Say Y 503 here unless you have verified that your setup is not 504 affected by entries in the DMI blacklist. Required by PNP 505 BIOS code. 506 507config GART_IOMMU 508 bool "GART IOMMU support" if EMBEDDED 509 default y 510 select SWIOTLB 511 select AGP 512 depends on X86_64 && PCI 513 help 514 Support for full DMA access of devices with 32bit memory access only 515 on systems with more than 3GB. This is usually needed for USB, 516 sound, many IDE/SATA chipsets and some other devices. 517 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART 518 based hardware IOMMU and a software bounce buffer based IOMMU used 519 on Intel systems and as fallback. 520 The code is only active when needed (enough memory and limited 521 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified 522 too. 523 524config CALGARY_IOMMU 525 bool "IBM Calgary IOMMU support" 526 select SWIOTLB 527 depends on X86_64 && PCI && EXPERIMENTAL 528 help 529 Support for hardware IOMMUs in IBM's xSeries x366 and x460 530 systems. Needed to run systems with more than 3GB of memory 531 properly with 32-bit PCI devices that do not support DAC 532 (Double Address Cycle). Calgary also supports bus level 533 isolation, where all DMAs pass through the IOMMU. This 534 prevents them from going anywhere except their intended 535 destination. This catches hard-to-find kernel bugs and 536 mis-behaving drivers and devices that do not use the DMA-API 537 properly to set up their DMA buffers. The IOMMU can be 538 turned off at boot time with the iommu=off parameter. 539 Normally the kernel will make the right choice by itself. 540 If unsure, say Y. 541 542config CALGARY_IOMMU_ENABLED_BY_DEFAULT 543 def_bool y 544 prompt "Should Calgary be enabled by default?" 545 depends on CALGARY_IOMMU 546 help 547 Should Calgary be enabled by default? if you choose 'y', Calgary 548 will be used (if it exists). If you choose 'n', Calgary will not be 549 used even if it exists. If you choose 'n' and would like to use 550 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 551 If unsure, say Y. 552 553config AMD_IOMMU 554 bool "AMD IOMMU support" 555 select SWIOTLB 556 depends on X86_64 && PCI && ACPI 557 help 558 With this option you can enable support for AMD IOMMU hardware in 559 your system. An IOMMU is a hardware component which provides 560 remapping of DMA memory accesses from devices. With an AMD IOMMU you 561 can isolate the the DMA memory of different devices and protect the 562 system from misbehaving device drivers or hardware. 563 564 You can find out if your system has an AMD IOMMU if you look into 565 your BIOS for an option to enable it or if you have an IVRS ACPI 566 table. 567 568# need this always selected by IOMMU for the VIA workaround 569config SWIOTLB 570 bool 571 help 572 Support for software bounce buffers used on x86-64 systems 573 which don't have a hardware IOMMU (e.g. the current generation 574 of Intel's x86-64 CPUs). Using this PCI devices which can only 575 access 32-bits of memory can be used on systems with more than 576 3 GB of memory. If unsure, say Y. 577 578config IOMMU_HELPER 579 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU) 580config MAXSMP 581 bool "Configure Maximum number of SMP Processors and NUMA Nodes" 582 depends on X86_64 && SMP 583 default n 584 help 585 Configure maximum number of CPUS and NUMA Nodes for this architecture. 586 If unsure, say N. 587 588if MAXSMP 589config NR_CPUS 590 int 591 default "4096" 592endif 593 594if !MAXSMP 595config NR_CPUS 596 int "Maximum number of CPUs (2-4096)" 597 range 2 4096 598 depends on SMP 599 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000 600 default "8" 601 help 602 This allows you to specify the maximum number of CPUs which this 603 kernel will support. The maximum supported value is 4096 and the 604 minimum value which makes sense is 2. 605 606 This is purely to save memory - each supported CPU adds 607 approximately eight kilobytes to the kernel image. 608endif 609 610config SCHED_SMT 611 bool "SMT (Hyperthreading) scheduler support" 612 depends on X86_HT 613 help 614 SMT scheduler support improves the CPU scheduler's decision making 615 when dealing with Intel Pentium 4 chips with HyperThreading at a 616 cost of slightly increased overhead in some places. If unsure say 617 N here. 618 619config SCHED_MC 620 def_bool y 621 prompt "Multi-core scheduler support" 622 depends on X86_HT 623 help 624 Multi-core scheduler support improves the CPU scheduler's decision 625 making when dealing with multi-core CPU chips at a cost of slightly 626 increased overhead in some places. If unsure say N here. 627 628source "kernel/Kconfig.preempt" 629 630config X86_UP_APIC 631 bool "Local APIC support on uniprocessors" 632 depends on X86_32 && !SMP && !(X86_VOYAGER || X86_GENERICARCH) 633 help 634 A local APIC (Advanced Programmable Interrupt Controller) is an 635 integrated interrupt controller in the CPU. If you have a single-CPU 636 system which has a processor with a local APIC, you can say Y here to 637 enable and use it. If you say Y here even though your machine doesn't 638 have a local APIC, then the kernel will still run with no slowdown at 639 all. The local APIC supports CPU-generated self-interrupts (timer, 640 performance counters), and the NMI watchdog which detects hard 641 lockups. 642 643config X86_UP_IOAPIC 644 bool "IO-APIC support on uniprocessors" 645 depends on X86_UP_APIC 646 help 647 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 648 SMP-capable replacement for PC-style interrupt controllers. Most 649 SMP systems and many recent uniprocessor systems have one. 650 651 If you have a single-CPU system with an IO-APIC, you can say Y here 652 to use it. If you say Y here even though your machine doesn't have 653 an IO-APIC, then the kernel will still run with no slowdown at all. 654 655config X86_LOCAL_APIC 656 def_bool y 657 depends on X86_64 || (X86_32 && (X86_UP_APIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH)) 658 659config X86_IO_APIC 660 def_bool y 661 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH)) 662 663config X86_VISWS_APIC 664 def_bool y 665 depends on X86_32 && X86_VISWS 666 667config X86_MCE 668 bool "Machine Check Exception" 669 depends on !X86_VOYAGER 670 ---help--- 671 Machine Check Exception support allows the processor to notify the 672 kernel if it detects a problem (e.g. overheating, component failure). 673 The action the kernel takes depends on the severity of the problem, 674 ranging from a warning message on the console, to halting the machine. 675 Your processor must be a Pentium or newer to support this - check the 676 flags in /proc/cpuinfo for mce. Note that some older Pentium systems 677 have a design flaw which leads to false MCE events - hence MCE is 678 disabled on all P5 processors, unless explicitly enabled with "mce" 679 as a boot argument. Similarly, if MCE is built in and creates a 680 problem on some new non-standard machine, you can boot with "nomce" 681 to disable it. MCE support simply ignores non-MCE processors like 682 the 386 and 486, so nearly everyone can say Y here. 683 684config X86_MCE_INTEL 685 def_bool y 686 prompt "Intel MCE features" 687 depends on X86_64 && X86_MCE && X86_LOCAL_APIC 688 help 689 Additional support for intel specific MCE features such as 690 the thermal monitor. 691 692config X86_MCE_AMD 693 def_bool y 694 prompt "AMD MCE features" 695 depends on X86_64 && X86_MCE && X86_LOCAL_APIC 696 help 697 Additional support for AMD specific MCE features such as 698 the DRAM Error Threshold. 699 700config X86_MCE_NONFATAL 701 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4" 702 depends on X86_32 && X86_MCE 703 help 704 Enabling this feature starts a timer that triggers every 5 seconds which 705 will look at the machine check registers to see if anything happened. 706 Non-fatal problems automatically get corrected (but still logged). 707 Disable this if you don't want to see these messages. 708 Seeing the messages this option prints out may be indicative of dying 709 or out-of-spec (ie, overclocked) hardware. 710 This option only does something on certain CPUs. 711 (AMD Athlon/Duron and Intel Pentium 4) 712 713config X86_MCE_P4THERMAL 714 bool "check for P4 thermal throttling interrupt." 715 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) 716 help 717 Enabling this feature will cause a message to be printed when the P4 718 enters thermal throttling. 719 720config VM86 721 bool "Enable VM86 support" if EMBEDDED 722 default y 723 depends on X86_32 724 help 725 This option is required by programs like DOSEMU to run 16-bit legacy 726 code on X86 processors. It also may be needed by software like 727 XFree86 to initialize some video cards via BIOS. Disabling this 728 option saves about 6k. 729 730config TOSHIBA 731 tristate "Toshiba Laptop support" 732 depends on X86_32 733 ---help--- 734 This adds a driver to safely access the System Management Mode of 735 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 736 not work on models with a Phoenix BIOS. The System Management Mode 737 is used to set the BIOS and power saving options on Toshiba portables. 738 739 For information on utilities to make use of this driver see the 740 Toshiba Linux utilities web site at: 741 <http://www.buzzard.org.uk/toshiba/>. 742 743 Say Y if you intend to run this kernel on a Toshiba portable. 744 Say N otherwise. 745 746config I8K 747 tristate "Dell laptop support" 748 ---help--- 749 This adds a driver to safely access the System Management Mode 750 of the CPU on the Dell Inspiron 8000. The System Management Mode 751 is used to read cpu temperature and cooling fan status and to 752 control the fans on the I8K portables. 753 754 This driver has been tested only on the Inspiron 8000 but it may 755 also work with other Dell laptops. You can force loading on other 756 models by passing the parameter `force=1' to the module. Use at 757 your own risk. 758 759 For information on utilities to make use of this driver see the 760 I8K Linux utilities web site at: 761 <http://people.debian.org/~dz/i8k/> 762 763 Say Y if you intend to run this kernel on a Dell Inspiron 8000. 764 Say N otherwise. 765 766config X86_REBOOTFIXUPS 767 def_bool n 768 prompt "Enable X86 board specific fixups for reboot" 769 depends on X86_32 && X86 770 ---help--- 771 This enables chipset and/or board specific fixups to be done 772 in order to get reboot to work correctly. This is only needed on 773 some combinations of hardware and BIOS. The symptom, for which 774 this config is intended, is when reboot ends with a stalled/hung 775 system. 776 777 Currently, the only fixup is for the Geode machines using 778 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 779 780 Say Y if you want to enable the fixup. Currently, it's safe to 781 enable this option even if you don't need it. 782 Say N otherwise. 783 784config MICROCODE 785 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support" 786 select FW_LOADER 787 ---help--- 788 If you say Y here, you will be able to update the microcode on 789 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II, 790 Pentium III, Pentium 4, Xeon etc. You will obviously need the 791 actual microcode binary data itself which is not shipped with the 792 Linux kernel. 793 794 For latest news and information on obtaining all the required 795 ingredients for this driver, check: 796 <http://www.urbanmyth.org/microcode/>. 797 798 To compile this driver as a module, choose M here: the 799 module will be called microcode. 800 801config MICROCODE_OLD_INTERFACE 802 def_bool y 803 depends on MICROCODE 804 805config X86_MSR 806 tristate "/dev/cpu/*/msr - Model-specific register support" 807 help 808 This device gives privileged processes access to the x86 809 Model-Specific Registers (MSRs). It is a character device with 810 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 811 MSR accesses are directed to a specific CPU on multi-processor 812 systems. 813 814config X86_CPUID 815 tristate "/dev/cpu/*/cpuid - CPU information support" 816 help 817 This device gives processes access to the x86 CPUID instruction to 818 be executed on a specific processor. It is a character device 819 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 820 /dev/cpu/31/cpuid. 821 822choice 823 prompt "High Memory Support" 824 default HIGHMEM4G if !X86_NUMAQ 825 default HIGHMEM64G if X86_NUMAQ 826 depends on X86_32 827 828config NOHIGHMEM 829 bool "off" 830 depends on !X86_NUMAQ 831 ---help--- 832 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 833 However, the address space of 32-bit x86 processors is only 4 834 Gigabytes large. That means that, if you have a large amount of 835 physical memory, not all of it can be "permanently mapped" by the 836 kernel. The physical memory that's not permanently mapped is called 837 "high memory". 838 839 If you are compiling a kernel which will never run on a machine with 840 more than 1 Gigabyte total physical RAM, answer "off" here (default 841 choice and suitable for most users). This will result in a "3GB/1GB" 842 split: 3GB are mapped so that each process sees a 3GB virtual memory 843 space and the remaining part of the 4GB virtual memory space is used 844 by the kernel to permanently map as much physical memory as 845 possible. 846 847 If the machine has between 1 and 4 Gigabytes physical RAM, then 848 answer "4GB" here. 849 850 If more than 4 Gigabytes is used then answer "64GB" here. This 851 selection turns Intel PAE (Physical Address Extension) mode on. 852 PAE implements 3-level paging on IA32 processors. PAE is fully 853 supported by Linux, PAE mode is implemented on all recent Intel 854 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 855 then the kernel will not boot on CPUs that don't support PAE! 856 857 The actual amount of total physical memory will either be 858 auto detected or can be forced by using a kernel command line option 859 such as "mem=256M". (Try "man bootparam" or see the documentation of 860 your boot loader (lilo or loadlin) about how to pass options to the 861 kernel at boot time.) 862 863 If unsure, say "off". 864 865config HIGHMEM4G 866 bool "4GB" 867 depends on !X86_NUMAQ 868 help 869 Select this if you have a 32-bit processor and between 1 and 4 870 gigabytes of physical RAM. 871 872config HIGHMEM64G 873 bool "64GB" 874 depends on !M386 && !M486 875 select X86_PAE 876 help 877 Select this if you have a 32-bit processor and more than 4 878 gigabytes of physical RAM. 879 880endchoice 881 882choice 883 depends on EXPERIMENTAL 884 prompt "Memory split" if EMBEDDED 885 default VMSPLIT_3G 886 depends on X86_32 887 help 888 Select the desired split between kernel and user memory. 889 890 If the address range available to the kernel is less than the 891 physical memory installed, the remaining memory will be available 892 as "high memory". Accessing high memory is a little more costly 893 than low memory, as it needs to be mapped into the kernel first. 894 Note that increasing the kernel address space limits the range 895 available to user programs, making the address space there 896 tighter. Selecting anything other than the default 3G/1G split 897 will also likely make your kernel incompatible with binary-only 898 kernel modules. 899 900 If you are not absolutely sure what you are doing, leave this 901 option alone! 902 903 config VMSPLIT_3G 904 bool "3G/1G user/kernel split" 905 config VMSPLIT_3G_OPT 906 depends on !X86_PAE 907 bool "3G/1G user/kernel split (for full 1G low memory)" 908 config VMSPLIT_2G 909 bool "2G/2G user/kernel split" 910 config VMSPLIT_2G_OPT 911 depends on !X86_PAE 912 bool "2G/2G user/kernel split (for full 2G low memory)" 913 config VMSPLIT_1G 914 bool "1G/3G user/kernel split" 915endchoice 916 917config PAGE_OFFSET 918 hex 919 default 0xB0000000 if VMSPLIT_3G_OPT 920 default 0x80000000 if VMSPLIT_2G 921 default 0x78000000 if VMSPLIT_2G_OPT 922 default 0x40000000 if VMSPLIT_1G 923 default 0xC0000000 924 depends on X86_32 925 926config HIGHMEM 927 def_bool y 928 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 929 930config X86_PAE 931 def_bool n 932 prompt "PAE (Physical Address Extension) Support" 933 depends on X86_32 && !HIGHMEM4G 934 select RESOURCES_64BIT 935 help 936 PAE is required for NX support, and furthermore enables 937 larger swapspace support for non-overcommit purposes. It 938 has the cost of more pagetable lookup overhead, and also 939 consumes more pagetable space per process. 940 941# Common NUMA Features 942config NUMA 943 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)" 944 depends on SMP 945 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL) 946 default n if X86_PC 947 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP) 948 help 949 Enable NUMA (Non Uniform Memory Access) support. 950 The kernel will try to allocate memory used by a CPU on the 951 local memory controller of the CPU and add some more 952 NUMA awareness to the kernel. 953 954 For i386 this is currently highly experimental and should be only 955 used for kernel development. It might also cause boot failures. 956 For x86_64 this is recommended on all multiprocessor Opteron systems. 957 If the system is EM64T, you should say N unless your system is 958 EM64T NUMA. 959 960comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI" 961 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI) 962 963config K8_NUMA 964 def_bool y 965 prompt "Old style AMD Opteron NUMA detection" 966 depends on X86_64 && NUMA && PCI 967 help 968 Enable K8 NUMA node topology detection. You should say Y here if 969 you have a multi processor AMD K8 system. This uses an old 970 method to read the NUMA configuration directly from the builtin 971 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA 972 instead, which also takes priority if both are compiled in. 973 974config X86_64_ACPI_NUMA 975 def_bool y 976 prompt "ACPI NUMA detection" 977 depends on X86_64 && NUMA && ACPI && PCI 978 select ACPI_NUMA 979 help 980 Enable ACPI SRAT based node topology detection. 981 982# Some NUMA nodes have memory ranges that span 983# other nodes. Even though a pfn is valid and 984# between a node's start and end pfns, it may not 985# reside on that node. See memmap_init_zone() 986# for details. 987config NODES_SPAN_OTHER_NODES 988 def_bool y 989 depends on X86_64_ACPI_NUMA 990 991config NUMA_EMU 992 bool "NUMA emulation" 993 depends on X86_64 && NUMA 994 help 995 Enable NUMA emulation. A flat machine will be split 996 into virtual nodes when booted with "numa=fake=N", where N is the 997 number of nodes. This is only useful for debugging. 998 999if MAXSMP 1000 1001config NODES_SHIFT 1002 int 1003 default "9" 1004endif 1005 1006if !MAXSMP 1007config NODES_SHIFT 1008 int "Maximum NUMA Nodes (as a power of 2)" 1009 range 1 9 if X86_64 1010 default "6" if X86_64 1011 default "4" if X86_NUMAQ 1012 default "3" 1013 depends on NEED_MULTIPLE_NODES 1014 help 1015 Specify the maximum number of NUMA Nodes available on the target 1016 system. Increases memory reserved to accomodate various tables. 1017endif 1018 1019config HAVE_ARCH_BOOTMEM_NODE 1020 def_bool y 1021 depends on X86_32 && NUMA 1022 1023config ARCH_HAVE_MEMORY_PRESENT 1024 def_bool y 1025 depends on X86_32 && DISCONTIGMEM 1026 1027config NEED_NODE_MEMMAP_SIZE 1028 def_bool y 1029 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1030 1031config HAVE_ARCH_ALLOC_REMAP 1032 def_bool y 1033 depends on X86_32 && NUMA 1034 1035config ARCH_FLATMEM_ENABLE 1036 def_bool y 1037 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA 1038 1039config ARCH_DISCONTIGMEM_ENABLE 1040 def_bool y 1041 depends on NUMA && X86_32 1042 1043config ARCH_DISCONTIGMEM_DEFAULT 1044 def_bool y 1045 depends on NUMA && X86_32 1046 1047config ARCH_SPARSEMEM_DEFAULT 1048 def_bool y 1049 depends on X86_64 1050 1051config ARCH_SPARSEMEM_ENABLE 1052 def_bool y 1053 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC) 1054 select SPARSEMEM_STATIC if X86_32 1055 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1056 1057config ARCH_SELECT_MEMORY_MODEL 1058 def_bool y 1059 depends on ARCH_SPARSEMEM_ENABLE 1060 1061config ARCH_MEMORY_PROBE 1062 def_bool X86_64 1063 depends on MEMORY_HOTPLUG 1064 1065source "mm/Kconfig" 1066 1067config HIGHPTE 1068 bool "Allocate 3rd-level pagetables from highmem" 1069 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G) 1070 help 1071 The VM uses one page table entry for each page of physical memory. 1072 For systems with a lot of RAM, this can be wasteful of precious 1073 low memory. Setting this option will put user-space page table 1074 entries in high memory. 1075 1076config MATH_EMULATION 1077 bool 1078 prompt "Math emulation" if X86_32 1079 ---help--- 1080 Linux can emulate a math coprocessor (used for floating point 1081 operations) if you don't have one. 486DX and Pentium processors have 1082 a math coprocessor built in, 486SX and 386 do not, unless you added 1083 a 487DX or 387, respectively. (The messages during boot time can 1084 give you some hints here ["man dmesg"].) Everyone needs either a 1085 coprocessor or this emulation. 1086 1087 If you don't have a math coprocessor, you need to say Y here; if you 1088 say Y here even though you have a coprocessor, the coprocessor will 1089 be used nevertheless. (This behavior can be changed with the kernel 1090 command line option "no387", which comes handy if your coprocessor 1091 is broken. Try "man bootparam" or see the documentation of your boot 1092 loader (lilo or loadlin) about how to pass options to the kernel at 1093 boot time.) This means that it is a good idea to say Y here if you 1094 intend to use this kernel on different machines. 1095 1096 More information about the internals of the Linux math coprocessor 1097 emulation can be found in <file:arch/x86/math-emu/README>. 1098 1099 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1100 kernel, it won't hurt. 1101 1102config MTRR 1103 bool "MTRR (Memory Type Range Register) support" 1104 ---help--- 1105 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1106 the Memory Type Range Registers (MTRRs) may be used to control 1107 processor access to memory ranges. This is most useful if you have 1108 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1109 allows bus write transfers to be combined into a larger transfer 1110 before bursting over the PCI/AGP bus. This can increase performance 1111 of image write operations 2.5 times or more. Saying Y here creates a 1112 /proc/mtrr file which may be used to manipulate your processor's 1113 MTRRs. Typically the X server should use this. 1114 1115 This code has a reasonably generic interface so that similar 1116 control registers on other processors can be easily supported 1117 as well: 1118 1119 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1120 Registers (ARRs) which provide a similar functionality to MTRRs. For 1121 these, the ARRs are used to emulate the MTRRs. 1122 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1123 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1124 write-combining. All of these processors are supported by this code 1125 and it makes sense to say Y here if you have one of them. 1126 1127 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1128 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1129 can lead to all sorts of problems, so it's good to say Y here. 1130 1131 You can safely say Y even if your machine doesn't have MTRRs, you'll 1132 just add about 9 KB to your kernel. 1133 1134 See <file:Documentation/mtrr.txt> for more information. 1135 1136config MTRR_SANITIZER 1137 bool 1138 prompt "MTRR cleanup support" 1139 depends on MTRR 1140 help 1141 Convert MTRR layout from continuous to discrete, so X drivers can 1142 add writeback entries. 1143 1144 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1145 The largest mtrr entry size for a continous block can be set with 1146 mtrr_chunk_size. 1147 1148 If unsure, say N. 1149 1150config MTRR_SANITIZER_ENABLE_DEFAULT 1151 int "MTRR cleanup enable value (0-1)" 1152 range 0 1 1153 default "0" 1154 depends on MTRR_SANITIZER 1155 help 1156 Enable mtrr cleanup default value 1157 1158config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1159 int "MTRR cleanup spare reg num (0-7)" 1160 range 0 7 1161 default "1" 1162 depends on MTRR_SANITIZER 1163 help 1164 mtrr cleanup spare entries default, it can be changed via 1165 mtrr_spare_reg_nr=N on the kernel command line. 1166 1167config X86_PAT 1168 bool 1169 prompt "x86 PAT support" 1170 depends on MTRR 1171 help 1172 Use PAT attributes to setup page level cache control. 1173 1174 PATs are the modern equivalents of MTRRs and are much more 1175 flexible than MTRRs. 1176 1177 Say N here if you see bootup problems (boot crash, boot hang, 1178 spontaneous reboots) or a non-working video driver. 1179 1180 If unsure, say Y. 1181 1182config EFI 1183 def_bool n 1184 prompt "EFI runtime service support" 1185 depends on ACPI 1186 ---help--- 1187 This enables the kernel to use EFI runtime services that are 1188 available (such as the EFI variable services). 1189 1190 This option is only useful on systems that have EFI firmware. 1191 In addition, you should use the latest ELILO loader available 1192 at <http://elilo.sourceforge.net> in order to take advantage 1193 of EFI runtime services. However, even with this option, the 1194 resultant kernel should continue to boot on existing non-EFI 1195 platforms. 1196 1197config IRQBALANCE 1198 def_bool y 1199 prompt "Enable kernel irq balancing" 1200 depends on X86_32 && SMP && X86_IO_APIC 1201 help 1202 The default yes will allow the kernel to do irq load balancing. 1203 Saying no will keep the kernel from doing irq load balancing. 1204 1205config SECCOMP 1206 def_bool y 1207 prompt "Enable seccomp to safely compute untrusted bytecode" 1208 depends on PROC_FS 1209 help 1210 This kernel feature is useful for number crunching applications 1211 that may need to compute untrusted bytecode during their 1212 execution. By using pipes or other transports made available to 1213 the process as file descriptors supporting the read/write 1214 syscalls, it's possible to isolate those applications in 1215 their own address space using seccomp. Once seccomp is 1216 enabled via /proc/<pid>/seccomp, it cannot be disabled 1217 and the task is only allowed to execute a few safe syscalls 1218 defined by each seccomp mode. 1219 1220 If unsure, say Y. Only embedded should say N here. 1221 1222config CC_STACKPROTECTOR 1223 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)" 1224 depends on X86_64 && EXPERIMENTAL && BROKEN 1225 help 1226 This option turns on the -fstack-protector GCC feature. This 1227 feature puts, at the beginning of critical functions, a canary 1228 value on the stack just before the return address, and validates 1229 the value just before actually returning. Stack based buffer 1230 overflows (that need to overwrite this return address) now also 1231 overwrite the canary, which gets detected and the attack is then 1232 neutralized via a kernel panic. 1233 1234 This feature requires gcc version 4.2 or above, or a distribution 1235 gcc with the feature backported. Older versions are automatically 1236 detected and for those versions, this configuration option is ignored. 1237 1238config CC_STACKPROTECTOR_ALL 1239 bool "Use stack-protector for all functions" 1240 depends on CC_STACKPROTECTOR 1241 help 1242 Normally, GCC only inserts the canary value protection for 1243 functions that use large-ish on-stack buffers. By enabling 1244 this option, GCC will be asked to do this for ALL functions. 1245 1246source kernel/Kconfig.hz 1247 1248config KEXEC 1249 bool "kexec system call" 1250 depends on X86_BIOS_REBOOT 1251 help 1252 kexec is a system call that implements the ability to shutdown your 1253 current kernel, and to start another kernel. It is like a reboot 1254 but it is independent of the system firmware. And like a reboot 1255 you can start any kernel with it, not just Linux. 1256 1257 The name comes from the similarity to the exec system call. 1258 1259 It is an ongoing process to be certain the hardware in a machine 1260 is properly shutdown, so do not be surprised if this code does not 1261 initially work for you. It may help to enable device hotplugging 1262 support. As of this writing the exact hardware interface is 1263 strongly in flux, so no good recommendation can be made. 1264 1265config CRASH_DUMP 1266 bool "kernel crash dumps (EXPERIMENTAL)" 1267 depends on X86_64 || (X86_32 && HIGHMEM) 1268 help 1269 Generate crash dump after being started by kexec. 1270 This should be normally only set in special crash dump kernels 1271 which are loaded in the main kernel with kexec-tools into 1272 a specially reserved region and then later executed after 1273 a crash by kdump/kexec. The crash dump kernel must be compiled 1274 to a memory address not used by the main kernel or BIOS using 1275 PHYSICAL_START, or it must be built as a relocatable image 1276 (CONFIG_RELOCATABLE=y). 1277 For more details see Documentation/kdump/kdump.txt 1278 1279config KEXEC_JUMP 1280 bool "kexec jump (EXPERIMENTAL)" 1281 depends on EXPERIMENTAL 1282 depends on KEXEC && HIBERNATION && X86_32 1283 help 1284 Jump between original kernel and kexeced kernel and invoke 1285 code in physical address mode via KEXEC 1286 1287config PHYSICAL_START 1288 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP) 1289 default "0x1000000" if X86_NUMAQ 1290 default "0x200000" if X86_64 1291 default "0x100000" 1292 help 1293 This gives the physical address where the kernel is loaded. 1294 1295 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1296 bzImage will decompress itself to above physical address and 1297 run from there. Otherwise, bzImage will run from the address where 1298 it has been loaded by the boot loader and will ignore above physical 1299 address. 1300 1301 In normal kdump cases one does not have to set/change this option 1302 as now bzImage can be compiled as a completely relocatable image 1303 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1304 address. This option is mainly useful for the folks who don't want 1305 to use a bzImage for capturing the crash dump and want to use a 1306 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1307 to be specifically compiled to run from a specific memory area 1308 (normally a reserved region) and this option comes handy. 1309 1310 So if you are using bzImage for capturing the crash dump, leave 1311 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y. 1312 Otherwise if you plan to use vmlinux for capturing the crash dump 1313 change this value to start of the reserved region (Typically 16MB 1314 0x1000000). In other words, it can be set based on the "X" value as 1315 specified in the "crashkernel=YM@XM" command line boot parameter 1316 passed to the panic-ed kernel. Typically this parameter is set as 1317 crashkernel=64M@16M. Please take a look at 1318 Documentation/kdump/kdump.txt for more details about crash dumps. 1319 1320 Usage of bzImage for capturing the crash dump is recommended as 1321 one does not have to build two kernels. Same kernel can be used 1322 as production kernel and capture kernel. Above option should have 1323 gone away after relocatable bzImage support is introduced. But it 1324 is present because there are users out there who continue to use 1325 vmlinux for dump capture. This option should go away down the 1326 line. 1327 1328 Don't change this unless you know what you are doing. 1329 1330config RELOCATABLE 1331 bool "Build a relocatable kernel (EXPERIMENTAL)" 1332 depends on EXPERIMENTAL 1333 help 1334 This builds a kernel image that retains relocation information 1335 so it can be loaded someplace besides the default 1MB. 1336 The relocations tend to make the kernel binary about 10% larger, 1337 but are discarded at runtime. 1338 1339 One use is for the kexec on panic case where the recovery kernel 1340 must live at a different physical address than the primary 1341 kernel. 1342 1343 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1344 it has been loaded at and the compile time physical address 1345 (CONFIG_PHYSICAL_START) is ignored. 1346 1347config PHYSICAL_ALIGN 1348 hex 1349 prompt "Alignment value to which kernel should be aligned" if X86_32 1350 default "0x100000" if X86_32 1351 default "0x200000" if X86_64 1352 range 0x2000 0x400000 1353 help 1354 This value puts the alignment restrictions on physical address 1355 where kernel is loaded and run from. Kernel is compiled for an 1356 address which meets above alignment restriction. 1357 1358 If bootloader loads the kernel at a non-aligned address and 1359 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1360 address aligned to above value and run from there. 1361 1362 If bootloader loads the kernel at a non-aligned address and 1363 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1364 load address and decompress itself to the address it has been 1365 compiled for and run from there. The address for which kernel is 1366 compiled already meets above alignment restrictions. Hence the 1367 end result is that kernel runs from a physical address meeting 1368 above alignment restrictions. 1369 1370 Don't change this unless you know what you are doing. 1371 1372config HOTPLUG_CPU 1373 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)" 1374 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER 1375 ---help--- 1376 Say Y here to experiment with turning CPUs off and on, and to 1377 enable suspend on SMP systems. CPUs can be controlled through 1378 /sys/devices/system/cpu. 1379 Say N if you want to disable CPU hotplug and don't need to 1380 suspend. 1381 1382config COMPAT_VDSO 1383 def_bool y 1384 prompt "Compat VDSO support" 1385 depends on X86_32 || IA32_EMULATION 1386 help 1387 Map the 32-bit VDSO to the predictable old-style address too. 1388 ---help--- 1389 Say N here if you are running a sufficiently recent glibc 1390 version (2.3.3 or later), to remove the high-mapped 1391 VDSO mapping and to exclusively use the randomized VDSO. 1392 1393 If unsure, say Y. 1394 1395endmenu 1396 1397config ARCH_ENABLE_MEMORY_HOTPLUG 1398 def_bool y 1399 depends on X86_64 || (X86_32 && HIGHMEM) 1400 1401config HAVE_ARCH_EARLY_PFN_TO_NID 1402 def_bool X86_64 1403 depends on NUMA 1404 1405menu "Power management options" 1406 depends on !X86_VOYAGER 1407 1408config ARCH_HIBERNATION_HEADER 1409 def_bool y 1410 depends on X86_64 && HIBERNATION 1411 1412source "kernel/power/Kconfig" 1413 1414source "drivers/acpi/Kconfig" 1415 1416config X86_APM_BOOT 1417 bool 1418 default y 1419 depends on APM || APM_MODULE 1420 1421menuconfig APM 1422 tristate "APM (Advanced Power Management) BIOS support" 1423 depends on X86_32 && PM_SLEEP 1424 ---help--- 1425 APM is a BIOS specification for saving power using several different 1426 techniques. This is mostly useful for battery powered laptops with 1427 APM compliant BIOSes. If you say Y here, the system time will be 1428 reset after a RESUME operation, the /proc/apm device will provide 1429 battery status information, and user-space programs will receive 1430 notification of APM "events" (e.g. battery status change). 1431 1432 If you select "Y" here, you can disable actual use of the APM 1433 BIOS by passing the "apm=off" option to the kernel at boot time. 1434 1435 Note that the APM support is almost completely disabled for 1436 machines with more than one CPU. 1437 1438 In order to use APM, you will need supporting software. For location 1439 and more information, read <file:Documentation/power/pm.txt> and the 1440 Battery Powered Linux mini-HOWTO, available from 1441 <http://www.tldp.org/docs.html#howto>. 1442 1443 This driver does not spin down disk drives (see the hdparm(8) 1444 manpage ("man 8 hdparm") for that), and it doesn't turn off 1445 VESA-compliant "green" monitors. 1446 1447 This driver does not support the TI 4000M TravelMate and the ACER 1448 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1449 desktop machines also don't have compliant BIOSes, and this driver 1450 may cause those machines to panic during the boot phase. 1451 1452 Generally, if you don't have a battery in your machine, there isn't 1453 much point in using this driver and you should say N. If you get 1454 random kernel OOPSes or reboots that don't seem to be related to 1455 anything, try disabling/enabling this option (or disabling/enabling 1456 APM in your BIOS). 1457 1458 Some other things you should try when experiencing seemingly random, 1459 "weird" problems: 1460 1461 1) make sure that you have enough swap space and that it is 1462 enabled. 1463 2) pass the "no-hlt" option to the kernel 1464 3) switch on floating point emulation in the kernel and pass 1465 the "no387" option to the kernel 1466 4) pass the "floppy=nodma" option to the kernel 1467 5) pass the "mem=4M" option to the kernel (thereby disabling 1468 all but the first 4 MB of RAM) 1469 6) make sure that the CPU is not over clocked. 1470 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1471 8) disable the cache from your BIOS settings 1472 9) install a fan for the video card or exchange video RAM 1473 10) install a better fan for the CPU 1474 11) exchange RAM chips 1475 12) exchange the motherboard. 1476 1477 To compile this driver as a module, choose M here: the 1478 module will be called apm. 1479 1480if APM 1481 1482config APM_IGNORE_USER_SUSPEND 1483 bool "Ignore USER SUSPEND" 1484 help 1485 This option will ignore USER SUSPEND requests. On machines with a 1486 compliant APM BIOS, you want to say N. However, on the NEC Versa M 1487 series notebooks, it is necessary to say Y because of a BIOS bug. 1488 1489config APM_DO_ENABLE 1490 bool "Enable PM at boot time" 1491 ---help--- 1492 Enable APM features at boot time. From page 36 of the APM BIOS 1493 specification: "When disabled, the APM BIOS does not automatically 1494 power manage devices, enter the Standby State, enter the Suspend 1495 State, or take power saving steps in response to CPU Idle calls." 1496 This driver will make CPU Idle calls when Linux is idle (unless this 1497 feature is turned off -- see "Do CPU IDLE calls", below). This 1498 should always save battery power, but more complicated APM features 1499 will be dependent on your BIOS implementation. You may need to turn 1500 this option off if your computer hangs at boot time when using APM 1501 support, or if it beeps continuously instead of suspending. Turn 1502 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1503 T400CDT. This is off by default since most machines do fine without 1504 this feature. 1505 1506config APM_CPU_IDLE 1507 bool "Make CPU Idle calls when idle" 1508 help 1509 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 1510 On some machines, this can activate improved power savings, such as 1511 a slowed CPU clock rate, when the machine is idle. These idle calls 1512 are made after the idle loop has run for some length of time (e.g., 1513 333 mS). On some machines, this will cause a hang at boot time or 1514 whenever the CPU becomes idle. (On machines with more than one CPU, 1515 this option does nothing.) 1516 1517config APM_DISPLAY_BLANK 1518 bool "Enable console blanking using APM" 1519 help 1520 Enable console blanking using the APM. Some laptops can use this to 1521 turn off the LCD backlight when the screen blanker of the Linux 1522 virtual console blanks the screen. Note that this is only used by 1523 the virtual console screen blanker, and won't turn off the backlight 1524 when using the X Window system. This also doesn't have anything to 1525 do with your VESA-compliant power-saving monitor. Further, this 1526 option doesn't work for all laptops -- it might not turn off your 1527 backlight at all, or it might print a lot of errors to the console, 1528 especially if you are using gpm. 1529 1530config APM_ALLOW_INTS 1531 bool "Allow interrupts during APM BIOS calls" 1532 help 1533 Normally we disable external interrupts while we are making calls to 1534 the APM BIOS as a measure to lessen the effects of a badly behaving 1535 BIOS implementation. The BIOS should reenable interrupts if it 1536 needs to. Unfortunately, some BIOSes do not -- especially those in 1537 many of the newer IBM Thinkpads. If you experience hangs when you 1538 suspend, try setting this to Y. Otherwise, say N. 1539 1540config APM_REAL_MODE_POWER_OFF 1541 bool "Use real mode APM BIOS call to power off" 1542 help 1543 Use real mode APM BIOS calls to switch off the computer. This is 1544 a work-around for a number of buggy BIOSes. Switch this option on if 1545 your computer crashes instead of powering off properly. 1546 1547endif # APM 1548 1549source "arch/x86/kernel/cpu/cpufreq/Kconfig" 1550 1551source "drivers/cpuidle/Kconfig" 1552 1553endmenu 1554 1555 1556menu "Bus options (PCI etc.)" 1557 1558config PCI 1559 bool "PCI support" 1560 default y 1561 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC) 1562 help 1563 Find out whether you have a PCI motherboard. PCI is the name of a 1564 bus system, i.e. the way the CPU talks to the other stuff inside 1565 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 1566 VESA. If you have PCI, say Y, otherwise N. 1567 1568choice 1569 prompt "PCI access mode" 1570 depends on X86_32 && PCI 1571 default PCI_GOANY 1572 ---help--- 1573 On PCI systems, the BIOS can be used to detect the PCI devices and 1574 determine their configuration. However, some old PCI motherboards 1575 have BIOS bugs and may crash if this is done. Also, some embedded 1576 PCI-based systems don't have any BIOS at all. Linux can also try to 1577 detect the PCI hardware directly without using the BIOS. 1578 1579 With this option, you can specify how Linux should detect the 1580 PCI devices. If you choose "BIOS", the BIOS will be used, 1581 if you choose "Direct", the BIOS won't be used, and if you 1582 choose "MMConfig", then PCI Express MMCONFIG will be used. 1583 If you choose "Any", the kernel will try MMCONFIG, then the 1584 direct access method and falls back to the BIOS if that doesn't 1585 work. If unsure, go with the default, which is "Any". 1586 1587config PCI_GOBIOS 1588 bool "BIOS" 1589 1590config PCI_GOMMCONFIG 1591 bool "MMConfig" 1592 1593config PCI_GODIRECT 1594 bool "Direct" 1595 1596config PCI_GOOLPC 1597 bool "OLPC" 1598 depends on OLPC 1599 1600config PCI_GOANY 1601 bool "Any" 1602 1603endchoice 1604 1605config PCI_BIOS 1606 def_bool y 1607 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 1608 1609# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 1610config PCI_DIRECT 1611 def_bool y 1612 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC)) 1613 1614config PCI_MMCONFIG 1615 def_bool y 1616 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY) 1617 1618config PCI_OLPC 1619 def_bool y 1620 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 1621 1622config PCI_DOMAINS 1623 def_bool y 1624 depends on PCI 1625 1626config PCI_MMCONFIG 1627 bool "Support mmconfig PCI config space access" 1628 depends on X86_64 && PCI && ACPI 1629 1630config DMAR 1631 bool "Support for DMA Remapping Devices (EXPERIMENTAL)" 1632 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL 1633 help 1634 DMA remapping (DMAR) devices support enables independent address 1635 translations for Direct Memory Access (DMA) from devices. 1636 These DMA remapping devices are reported via ACPI tables 1637 and include PCI device scope covered by these DMA 1638 remapping devices. 1639 1640config DMAR_GFX_WA 1641 def_bool y 1642 prompt "Support for Graphics workaround" 1643 depends on DMAR 1644 help 1645 Current Graphics drivers tend to use physical address 1646 for DMA and avoid using DMA APIs. Setting this config 1647 option permits the IOMMU driver to set a unity map for 1648 all the OS-visible memory. Hence the driver can continue 1649 to use physical addresses for DMA. 1650 1651config DMAR_FLOPPY_WA 1652 def_bool y 1653 depends on DMAR 1654 help 1655 Floppy disk drivers are know to bypass DMA API calls 1656 thereby failing to work when IOMMU is enabled. This 1657 workaround will setup a 1:1 mapping for the first 1658 16M to make floppy (an ISA device) work. 1659 1660source "drivers/pci/pcie/Kconfig" 1661 1662source "drivers/pci/Kconfig" 1663 1664# x86_64 have no ISA slots, but do have ISA-style DMA. 1665config ISA_DMA_API 1666 def_bool y 1667 1668if X86_32 1669 1670config ISA 1671 bool "ISA support" 1672 depends on !X86_VOYAGER 1673 help 1674 Find out whether you have ISA slots on your motherboard. ISA is the 1675 name of a bus system, i.e. the way the CPU talks to the other stuff 1676 inside your box. Other bus systems are PCI, EISA, MicroChannel 1677 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 1678 newer boards don't support it. If you have ISA, say Y, otherwise N. 1679 1680config EISA 1681 bool "EISA support" 1682 depends on ISA 1683 ---help--- 1684 The Extended Industry Standard Architecture (EISA) bus was 1685 developed as an open alternative to the IBM MicroChannel bus. 1686 1687 The EISA bus provided some of the features of the IBM MicroChannel 1688 bus while maintaining backward compatibility with cards made for 1689 the older ISA bus. The EISA bus saw limited use between 1988 and 1690 1995 when it was made obsolete by the PCI bus. 1691 1692 Say Y here if you are building a kernel for an EISA-based machine. 1693 1694 Otherwise, say N. 1695 1696source "drivers/eisa/Kconfig" 1697 1698config MCA 1699 bool "MCA support" if !X86_VOYAGER 1700 default y if X86_VOYAGER 1701 help 1702 MicroChannel Architecture is found in some IBM PS/2 machines and 1703 laptops. It is a bus system similar to PCI or ISA. See 1704 <file:Documentation/mca.txt> (and especially the web page given 1705 there) before attempting to build an MCA bus kernel. 1706 1707source "drivers/mca/Kconfig" 1708 1709config SCx200 1710 tristate "NatSemi SCx200 support" 1711 depends on !X86_VOYAGER 1712 help 1713 This provides basic support for National Semiconductor's 1714 (now AMD's) Geode processors. The driver probes for the 1715 PCI-IDs of several on-chip devices, so its a good dependency 1716 for other scx200_* drivers. 1717 1718 If compiled as a module, the driver is named scx200. 1719 1720config SCx200HR_TIMER 1721 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 1722 depends on SCx200 && GENERIC_TIME 1723 default y 1724 help 1725 This driver provides a clocksource built upon the on-chip 1726 27MHz high-resolution timer. Its also a workaround for 1727 NSC Geode SC-1100's buggy TSC, which loses time when the 1728 processor goes idle (as is done by the scheduler). The 1729 other workaround is idle=poll boot option. 1730 1731config GEODE_MFGPT_TIMER 1732 def_bool y 1733 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events" 1734 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS 1735 help 1736 This driver provides a clock event source based on the MFGPT 1737 timer(s) in the CS5535 and CS5536 companion chip for the geode. 1738 MFGPTs have a better resolution and max interval than the 1739 generic PIT, and are suitable for use as high-res timers. 1740 1741config OLPC 1742 bool "One Laptop Per Child support" 1743 default n 1744 help 1745 Add support for detecting the unique features of the OLPC 1746 XO hardware. 1747 1748endif # X86_32 1749 1750config K8_NB 1751 def_bool y 1752 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA))) 1753 1754source "drivers/pcmcia/Kconfig" 1755 1756source "drivers/pci/hotplug/Kconfig" 1757 1758endmenu 1759 1760 1761menu "Executable file formats / Emulations" 1762 1763source "fs/Kconfig.binfmt" 1764 1765config IA32_EMULATION 1766 bool "IA32 Emulation" 1767 depends on X86_64 1768 select COMPAT_BINFMT_ELF 1769 help 1770 Include code to run 32-bit programs under a 64-bit kernel. You should 1771 likely turn this on, unless you're 100% sure that you don't have any 1772 32-bit programs left. 1773 1774config IA32_AOUT 1775 tristate "IA32 a.out support" 1776 depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT 1777 help 1778 Support old a.out binaries in the 32bit emulation. 1779 1780config COMPAT 1781 def_bool y 1782 depends on IA32_EMULATION 1783 1784config COMPAT_FOR_U64_ALIGNMENT 1785 def_bool COMPAT 1786 depends on X86_64 1787 1788config SYSVIPC_COMPAT 1789 def_bool y 1790 depends on X86_64 && COMPAT && SYSVIPC 1791 1792endmenu 1793 1794 1795source "net/Kconfig" 1796 1797source "drivers/Kconfig" 1798 1799source "drivers/firmware/Kconfig" 1800 1801source "fs/Kconfig" 1802 1803source "arch/x86/Kconfig.debug" 1804 1805source "security/Kconfig" 1806 1807source "crypto/Kconfig" 1808 1809source "arch/x86/kvm/Kconfig" 1810 1811source "lib/Kconfig" 1812