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_KPROBES 26 select ARCH_WANT_OPTIONAL_GPIOLIB 27 select HAVE_KRETPROBES 28 select HAVE_DYNAMIC_FTRACE 29 select HAVE_FTRACE 30 select HAVE_KVM if ((X86_32 && !X86_VOYAGER && !X86_VISWS && !X86_NUMAQ) || X86_64) 31 select HAVE_ARCH_KGDB if !X86_VOYAGER 32 select HAVE_GENERIC_DMA_COHERENT if X86_32 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) 580 581config MAXSMP 582 bool "Configure Maximum number of SMP Processors and NUMA Nodes" 583 depends on X86_64 && SMP && BROKEN 584 default n 585 help 586 Configure maximum number of CPUS and NUMA Nodes for this architecture. 587 If unsure, say N. 588 589config NR_CPUS 590 int "Maximum number of CPUs (2-512)" if !MAXSMP 591 range 2 512 592 depends on SMP 593 default "4096" if MAXSMP 594 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000 595 default "8" 596 help 597 This allows you to specify the maximum number of CPUs which this 598 kernel will support. The maximum supported value is 512 and the 599 minimum value which makes sense is 2. 600 601 This is purely to save memory - each supported CPU adds 602 approximately eight kilobytes to the kernel image. 603 604config SCHED_SMT 605 bool "SMT (Hyperthreading) scheduler support" 606 depends on X86_HT 607 help 608 SMT scheduler support improves the CPU scheduler's decision making 609 when dealing with Intel Pentium 4 chips with HyperThreading at a 610 cost of slightly increased overhead in some places. If unsure say 611 N here. 612 613config SCHED_MC 614 def_bool y 615 prompt "Multi-core scheduler support" 616 depends on X86_HT 617 help 618 Multi-core scheduler support improves the CPU scheduler's decision 619 making when dealing with multi-core CPU chips at a cost of slightly 620 increased overhead in some places. If unsure say N here. 621 622source "kernel/Kconfig.preempt" 623 624config X86_UP_APIC 625 bool "Local APIC support on uniprocessors" 626 depends on X86_32 && !SMP && !(X86_VOYAGER || X86_GENERICARCH) 627 help 628 A local APIC (Advanced Programmable Interrupt Controller) is an 629 integrated interrupt controller in the CPU. If you have a single-CPU 630 system which has a processor with a local APIC, you can say Y here to 631 enable and use it. If you say Y here even though your machine doesn't 632 have a local APIC, then the kernel will still run with no slowdown at 633 all. The local APIC supports CPU-generated self-interrupts (timer, 634 performance counters), and the NMI watchdog which detects hard 635 lockups. 636 637config X86_UP_IOAPIC 638 bool "IO-APIC support on uniprocessors" 639 depends on X86_UP_APIC 640 help 641 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 642 SMP-capable replacement for PC-style interrupt controllers. Most 643 SMP systems and many recent uniprocessor systems have one. 644 645 If you have a single-CPU system with an IO-APIC, you can say Y here 646 to use it. If you say Y here even though your machine doesn't have 647 an IO-APIC, then the kernel will still run with no slowdown at all. 648 649config X86_LOCAL_APIC 650 def_bool y 651 depends on X86_64 || (X86_32 && (X86_UP_APIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH)) 652 653config X86_IO_APIC 654 def_bool y 655 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !X86_VOYAGER) || X86_GENERICARCH)) 656 657config X86_VISWS_APIC 658 def_bool y 659 depends on X86_32 && X86_VISWS 660 661config X86_MCE 662 bool "Machine Check Exception" 663 depends on !X86_VOYAGER 664 ---help--- 665 Machine Check Exception support allows the processor to notify the 666 kernel if it detects a problem (e.g. overheating, component failure). 667 The action the kernel takes depends on the severity of the problem, 668 ranging from a warning message on the console, to halting the machine. 669 Your processor must be a Pentium or newer to support this - check the 670 flags in /proc/cpuinfo for mce. Note that some older Pentium systems 671 have a design flaw which leads to false MCE events - hence MCE is 672 disabled on all P5 processors, unless explicitly enabled with "mce" 673 as a boot argument. Similarly, if MCE is built in and creates a 674 problem on some new non-standard machine, you can boot with "nomce" 675 to disable it. MCE support simply ignores non-MCE processors like 676 the 386 and 486, so nearly everyone can say Y here. 677 678config X86_MCE_INTEL 679 def_bool y 680 prompt "Intel MCE features" 681 depends on X86_64 && X86_MCE && X86_LOCAL_APIC 682 help 683 Additional support for intel specific MCE features such as 684 the thermal monitor. 685 686config X86_MCE_AMD 687 def_bool y 688 prompt "AMD MCE features" 689 depends on X86_64 && X86_MCE && X86_LOCAL_APIC 690 help 691 Additional support for AMD specific MCE features such as 692 the DRAM Error Threshold. 693 694config X86_MCE_NONFATAL 695 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4" 696 depends on X86_32 && X86_MCE 697 help 698 Enabling this feature starts a timer that triggers every 5 seconds which 699 will look at the machine check registers to see if anything happened. 700 Non-fatal problems automatically get corrected (but still logged). 701 Disable this if you don't want to see these messages. 702 Seeing the messages this option prints out may be indicative of dying 703 or out-of-spec (ie, overclocked) hardware. 704 This option only does something on certain CPUs. 705 (AMD Athlon/Duron and Intel Pentium 4) 706 707config X86_MCE_P4THERMAL 708 bool "check for P4 thermal throttling interrupt." 709 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) 710 help 711 Enabling this feature will cause a message to be printed when the P4 712 enters thermal throttling. 713 714config VM86 715 bool "Enable VM86 support" if EMBEDDED 716 default y 717 depends on X86_32 718 help 719 This option is required by programs like DOSEMU to run 16-bit legacy 720 code on X86 processors. It also may be needed by software like 721 XFree86 to initialize some video cards via BIOS. Disabling this 722 option saves about 6k. 723 724config TOSHIBA 725 tristate "Toshiba Laptop support" 726 depends on X86_32 727 ---help--- 728 This adds a driver to safely access the System Management Mode of 729 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 730 not work on models with a Phoenix BIOS. The System Management Mode 731 is used to set the BIOS and power saving options on Toshiba portables. 732 733 For information on utilities to make use of this driver see the 734 Toshiba Linux utilities web site at: 735 <http://www.buzzard.org.uk/toshiba/>. 736 737 Say Y if you intend to run this kernel on a Toshiba portable. 738 Say N otherwise. 739 740config I8K 741 tristate "Dell laptop support" 742 ---help--- 743 This adds a driver to safely access the System Management Mode 744 of the CPU on the Dell Inspiron 8000. The System Management Mode 745 is used to read cpu temperature and cooling fan status and to 746 control the fans on the I8K portables. 747 748 This driver has been tested only on the Inspiron 8000 but it may 749 also work with other Dell laptops. You can force loading on other 750 models by passing the parameter `force=1' to the module. Use at 751 your own risk. 752 753 For information on utilities to make use of this driver see the 754 I8K Linux utilities web site at: 755 <http://people.debian.org/~dz/i8k/> 756 757 Say Y if you intend to run this kernel on a Dell Inspiron 8000. 758 Say N otherwise. 759 760config X86_REBOOTFIXUPS 761 def_bool n 762 prompt "Enable X86 board specific fixups for reboot" 763 depends on X86_32 && X86 764 ---help--- 765 This enables chipset and/or board specific fixups to be done 766 in order to get reboot to work correctly. This is only needed on 767 some combinations of hardware and BIOS. The symptom, for which 768 this config is intended, is when reboot ends with a stalled/hung 769 system. 770 771 Currently, the only fixup is for the Geode machines using 772 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 773 774 Say Y if you want to enable the fixup. Currently, it's safe to 775 enable this option even if you don't need it. 776 Say N otherwise. 777 778config MICROCODE 779 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support" 780 select FW_LOADER 781 ---help--- 782 If you say Y here, you will be able to update the microcode on 783 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II, 784 Pentium III, Pentium 4, Xeon etc. You will obviously need the 785 actual microcode binary data itself which is not shipped with the 786 Linux kernel. 787 788 For latest news and information on obtaining all the required 789 ingredients for this driver, check: 790 <http://www.urbanmyth.org/microcode/>. 791 792 To compile this driver as a module, choose M here: the 793 module will be called microcode. 794 795config MICROCODE_OLD_INTERFACE 796 def_bool y 797 depends on MICROCODE 798 799config X86_MSR 800 tristate "/dev/cpu/*/msr - Model-specific register support" 801 help 802 This device gives privileged processes access to the x86 803 Model-Specific Registers (MSRs). It is a character device with 804 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 805 MSR accesses are directed to a specific CPU on multi-processor 806 systems. 807 808config X86_CPUID 809 tristate "/dev/cpu/*/cpuid - CPU information support" 810 help 811 This device gives processes access to the x86 CPUID instruction to 812 be executed on a specific processor. It is a character device 813 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 814 /dev/cpu/31/cpuid. 815 816choice 817 prompt "High Memory Support" 818 default HIGHMEM4G if !X86_NUMAQ 819 default HIGHMEM64G if X86_NUMAQ 820 depends on X86_32 821 822config NOHIGHMEM 823 bool "off" 824 depends on !X86_NUMAQ 825 ---help--- 826 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 827 However, the address space of 32-bit x86 processors is only 4 828 Gigabytes large. That means that, if you have a large amount of 829 physical memory, not all of it can be "permanently mapped" by the 830 kernel. The physical memory that's not permanently mapped is called 831 "high memory". 832 833 If you are compiling a kernel which will never run on a machine with 834 more than 1 Gigabyte total physical RAM, answer "off" here (default 835 choice and suitable for most users). This will result in a "3GB/1GB" 836 split: 3GB are mapped so that each process sees a 3GB virtual memory 837 space and the remaining part of the 4GB virtual memory space is used 838 by the kernel to permanently map as much physical memory as 839 possible. 840 841 If the machine has between 1 and 4 Gigabytes physical RAM, then 842 answer "4GB" here. 843 844 If more than 4 Gigabytes is used then answer "64GB" here. This 845 selection turns Intel PAE (Physical Address Extension) mode on. 846 PAE implements 3-level paging on IA32 processors. PAE is fully 847 supported by Linux, PAE mode is implemented on all recent Intel 848 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 849 then the kernel will not boot on CPUs that don't support PAE! 850 851 The actual amount of total physical memory will either be 852 auto detected or can be forced by using a kernel command line option 853 such as "mem=256M". (Try "man bootparam" or see the documentation of 854 your boot loader (lilo or loadlin) about how to pass options to the 855 kernel at boot time.) 856 857 If unsure, say "off". 858 859config HIGHMEM4G 860 bool "4GB" 861 depends on !X86_NUMAQ 862 help 863 Select this if you have a 32-bit processor and between 1 and 4 864 gigabytes of physical RAM. 865 866config HIGHMEM64G 867 bool "64GB" 868 depends on !M386 && !M486 869 select X86_PAE 870 help 871 Select this if you have a 32-bit processor and more than 4 872 gigabytes of physical RAM. 873 874endchoice 875 876choice 877 depends on EXPERIMENTAL 878 prompt "Memory split" if EMBEDDED 879 default VMSPLIT_3G 880 depends on X86_32 881 help 882 Select the desired split between kernel and user memory. 883 884 If the address range available to the kernel is less than the 885 physical memory installed, the remaining memory will be available 886 as "high memory". Accessing high memory is a little more costly 887 than low memory, as it needs to be mapped into the kernel first. 888 Note that increasing the kernel address space limits the range 889 available to user programs, making the address space there 890 tighter. Selecting anything other than the default 3G/1G split 891 will also likely make your kernel incompatible with binary-only 892 kernel modules. 893 894 If you are not absolutely sure what you are doing, leave this 895 option alone! 896 897 config VMSPLIT_3G 898 bool "3G/1G user/kernel split" 899 config VMSPLIT_3G_OPT 900 depends on !X86_PAE 901 bool "3G/1G user/kernel split (for full 1G low memory)" 902 config VMSPLIT_2G 903 bool "2G/2G user/kernel split" 904 config VMSPLIT_2G_OPT 905 depends on !X86_PAE 906 bool "2G/2G user/kernel split (for full 2G low memory)" 907 config VMSPLIT_1G 908 bool "1G/3G user/kernel split" 909endchoice 910 911config PAGE_OFFSET 912 hex 913 default 0xB0000000 if VMSPLIT_3G_OPT 914 default 0x80000000 if VMSPLIT_2G 915 default 0x78000000 if VMSPLIT_2G_OPT 916 default 0x40000000 if VMSPLIT_1G 917 default 0xC0000000 918 depends on X86_32 919 920config HIGHMEM 921 def_bool y 922 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 923 924config X86_PAE 925 def_bool n 926 prompt "PAE (Physical Address Extension) Support" 927 depends on X86_32 && !HIGHMEM4G 928 select RESOURCES_64BIT 929 help 930 PAE is required for NX support, and furthermore enables 931 larger swapspace support for non-overcommit purposes. It 932 has the cost of more pagetable lookup overhead, and also 933 consumes more pagetable space per process. 934 935# Common NUMA Features 936config NUMA 937 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)" 938 depends on SMP 939 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL) 940 default n if X86_PC 941 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP) 942 help 943 Enable NUMA (Non Uniform Memory Access) support. 944 The kernel will try to allocate memory used by a CPU on the 945 local memory controller of the CPU and add some more 946 NUMA awareness to the kernel. 947 948 For 32-bit this is currently highly experimental and should be only 949 used for kernel development. It might also cause boot failures. 950 For 64-bit this is recommended on all multiprocessor Opteron systems. 951 If the system is EM64T, you should say N unless your system is 952 EM64T NUMA. 953 954comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI" 955 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI) 956 957config K8_NUMA 958 def_bool y 959 prompt "Old style AMD Opteron NUMA detection" 960 depends on X86_64 && NUMA && PCI 961 help 962 Enable K8 NUMA node topology detection. You should say Y here if 963 you have a multi processor AMD K8 system. This uses an old 964 method to read the NUMA configuration directly from the builtin 965 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA 966 instead, which also takes priority if both are compiled in. 967 968config X86_64_ACPI_NUMA 969 def_bool y 970 prompt "ACPI NUMA detection" 971 depends on X86_64 && NUMA && ACPI && PCI 972 select ACPI_NUMA 973 help 974 Enable ACPI SRAT based node topology detection. 975 976# Some NUMA nodes have memory ranges that span 977# other nodes. Even though a pfn is valid and 978# between a node's start and end pfns, it may not 979# reside on that node. See memmap_init_zone() 980# for details. 981config NODES_SPAN_OTHER_NODES 982 def_bool y 983 depends on X86_64_ACPI_NUMA 984 985config NUMA_EMU 986 bool "NUMA emulation" 987 depends on X86_64 && NUMA 988 help 989 Enable NUMA emulation. A flat machine will be split 990 into virtual nodes when booted with "numa=fake=N", where N is the 991 number of nodes. This is only useful for debugging. 992 993config NODES_SHIFT 994 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 995 range 1 9 if X86_64 996 default "9" if MAXSMP 997 default "6" if X86_64 998 default "4" if X86_NUMAQ 999 default "3" 1000 depends on NEED_MULTIPLE_NODES 1001 help 1002 Specify the maximum number of NUMA Nodes available on the target 1003 system. Increases memory reserved to accomodate various tables. 1004 1005config HAVE_ARCH_BOOTMEM_NODE 1006 def_bool y 1007 depends on X86_32 && NUMA 1008 1009config ARCH_HAVE_MEMORY_PRESENT 1010 def_bool y 1011 depends on X86_32 && DISCONTIGMEM 1012 1013config NEED_NODE_MEMMAP_SIZE 1014 def_bool y 1015 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1016 1017config HAVE_ARCH_ALLOC_REMAP 1018 def_bool y 1019 depends on X86_32 && NUMA 1020 1021config ARCH_FLATMEM_ENABLE 1022 def_bool y 1023 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA 1024 1025config ARCH_DISCONTIGMEM_ENABLE 1026 def_bool y 1027 depends on NUMA && X86_32 1028 1029config ARCH_DISCONTIGMEM_DEFAULT 1030 def_bool y 1031 depends on NUMA && X86_32 1032 1033config ARCH_SPARSEMEM_DEFAULT 1034 def_bool y 1035 depends on X86_64 1036 1037config ARCH_SPARSEMEM_ENABLE 1038 def_bool y 1039 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC) 1040 select SPARSEMEM_STATIC if X86_32 1041 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1042 1043config ARCH_SELECT_MEMORY_MODEL 1044 def_bool y 1045 depends on ARCH_SPARSEMEM_ENABLE 1046 1047config ARCH_MEMORY_PROBE 1048 def_bool X86_64 1049 depends on MEMORY_HOTPLUG 1050 1051source "mm/Kconfig" 1052 1053config HIGHPTE 1054 bool "Allocate 3rd-level pagetables from highmem" 1055 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G) 1056 help 1057 The VM uses one page table entry for each page of physical memory. 1058 For systems with a lot of RAM, this can be wasteful of precious 1059 low memory. Setting this option will put user-space page table 1060 entries in high memory. 1061 1062config MATH_EMULATION 1063 bool 1064 prompt "Math emulation" if X86_32 1065 ---help--- 1066 Linux can emulate a math coprocessor (used for floating point 1067 operations) if you don't have one. 486DX and Pentium processors have 1068 a math coprocessor built in, 486SX and 386 do not, unless you added 1069 a 487DX or 387, respectively. (The messages during boot time can 1070 give you some hints here ["man dmesg"].) Everyone needs either a 1071 coprocessor or this emulation. 1072 1073 If you don't have a math coprocessor, you need to say Y here; if you 1074 say Y here even though you have a coprocessor, the coprocessor will 1075 be used nevertheless. (This behavior can be changed with the kernel 1076 command line option "no387", which comes handy if your coprocessor 1077 is broken. Try "man bootparam" or see the documentation of your boot 1078 loader (lilo or loadlin) about how to pass options to the kernel at 1079 boot time.) This means that it is a good idea to say Y here if you 1080 intend to use this kernel on different machines. 1081 1082 More information about the internals of the Linux math coprocessor 1083 emulation can be found in <file:arch/x86/math-emu/README>. 1084 1085 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1086 kernel, it won't hurt. 1087 1088config MTRR 1089 bool "MTRR (Memory Type Range Register) support" 1090 ---help--- 1091 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1092 the Memory Type Range Registers (MTRRs) may be used to control 1093 processor access to memory ranges. This is most useful if you have 1094 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1095 allows bus write transfers to be combined into a larger transfer 1096 before bursting over the PCI/AGP bus. This can increase performance 1097 of image write operations 2.5 times or more. Saying Y here creates a 1098 /proc/mtrr file which may be used to manipulate your processor's 1099 MTRRs. Typically the X server should use this. 1100 1101 This code has a reasonably generic interface so that similar 1102 control registers on other processors can be easily supported 1103 as well: 1104 1105 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1106 Registers (ARRs) which provide a similar functionality to MTRRs. For 1107 these, the ARRs are used to emulate the MTRRs. 1108 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1109 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1110 write-combining. All of these processors are supported by this code 1111 and it makes sense to say Y here if you have one of them. 1112 1113 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1114 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1115 can lead to all sorts of problems, so it's good to say Y here. 1116 1117 You can safely say Y even if your machine doesn't have MTRRs, you'll 1118 just add about 9 KB to your kernel. 1119 1120 See <file:Documentation/mtrr.txt> for more information. 1121 1122config MTRR_SANITIZER 1123 bool 1124 prompt "MTRR cleanup support" 1125 depends on MTRR 1126 help 1127 Convert MTRR layout from continuous to discrete, so X drivers can 1128 add writeback entries. 1129 1130 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1131 The largest mtrr entry size for a continous block can be set with 1132 mtrr_chunk_size. 1133 1134 If unsure, say N. 1135 1136config MTRR_SANITIZER_ENABLE_DEFAULT 1137 int "MTRR cleanup enable value (0-1)" 1138 range 0 1 1139 default "0" 1140 depends on MTRR_SANITIZER 1141 help 1142 Enable mtrr cleanup default value 1143 1144config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1145 int "MTRR cleanup spare reg num (0-7)" 1146 range 0 7 1147 default "1" 1148 depends on MTRR_SANITIZER 1149 help 1150 mtrr cleanup spare entries default, it can be changed via 1151 mtrr_spare_reg_nr=N on the kernel command line. 1152 1153config X86_PAT 1154 bool 1155 prompt "x86 PAT support" 1156 depends on MTRR 1157 help 1158 Use PAT attributes to setup page level cache control. 1159 1160 PATs are the modern equivalents of MTRRs and are much more 1161 flexible than MTRRs. 1162 1163 Say N here if you see bootup problems (boot crash, boot hang, 1164 spontaneous reboots) or a non-working video driver. 1165 1166 If unsure, say Y. 1167 1168config EFI 1169 def_bool n 1170 prompt "EFI runtime service support" 1171 depends on ACPI 1172 ---help--- 1173 This enables the kernel to use EFI runtime services that are 1174 available (such as the EFI variable services). 1175 1176 This option is only useful on systems that have EFI firmware. 1177 In addition, you should use the latest ELILO loader available 1178 at <http://elilo.sourceforge.net> in order to take advantage 1179 of EFI runtime services. However, even with this option, the 1180 resultant kernel should continue to boot on existing non-EFI 1181 platforms. 1182 1183config IRQBALANCE 1184 def_bool y 1185 prompt "Enable kernel irq balancing" 1186 depends on X86_32 && SMP && X86_IO_APIC 1187 help 1188 The default yes will allow the kernel to do irq load balancing. 1189 Saying no will keep the kernel from doing irq load balancing. 1190 1191config SECCOMP 1192 def_bool y 1193 prompt "Enable seccomp to safely compute untrusted bytecode" 1194 depends on PROC_FS 1195 help 1196 This kernel feature is useful for number crunching applications 1197 that may need to compute untrusted bytecode during their 1198 execution. By using pipes or other transports made available to 1199 the process as file descriptors supporting the read/write 1200 syscalls, it's possible to isolate those applications in 1201 their own address space using seccomp. Once seccomp is 1202 enabled via /proc/<pid>/seccomp, it cannot be disabled 1203 and the task is only allowed to execute a few safe syscalls 1204 defined by each seccomp mode. 1205 1206 If unsure, say Y. Only embedded should say N here. 1207 1208config CC_STACKPROTECTOR 1209 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)" 1210 depends on X86_64 && EXPERIMENTAL && BROKEN 1211 help 1212 This option turns on the -fstack-protector GCC feature. This 1213 feature puts, at the beginning of critical functions, a canary 1214 value on the stack just before the return address, and validates 1215 the value just before actually returning. Stack based buffer 1216 overflows (that need to overwrite this return address) now also 1217 overwrite the canary, which gets detected and the attack is then 1218 neutralized via a kernel panic. 1219 1220 This feature requires gcc version 4.2 or above, or a distribution 1221 gcc with the feature backported. Older versions are automatically 1222 detected and for those versions, this configuration option is ignored. 1223 1224config CC_STACKPROTECTOR_ALL 1225 bool "Use stack-protector for all functions" 1226 depends on CC_STACKPROTECTOR 1227 help 1228 Normally, GCC only inserts the canary value protection for 1229 functions that use large-ish on-stack buffers. By enabling 1230 this option, GCC will be asked to do this for ALL functions. 1231 1232source kernel/Kconfig.hz 1233 1234config KEXEC 1235 bool "kexec system call" 1236 depends on X86_BIOS_REBOOT 1237 help 1238 kexec is a system call that implements the ability to shutdown your 1239 current kernel, and to start another kernel. It is like a reboot 1240 but it is independent of the system firmware. And like a reboot 1241 you can start any kernel with it, not just Linux. 1242 1243 The name comes from the similarity to the exec system call. 1244 1245 It is an ongoing process to be certain the hardware in a machine 1246 is properly shutdown, so do not be surprised if this code does not 1247 initially work for you. It may help to enable device hotplugging 1248 support. As of this writing the exact hardware interface is 1249 strongly in flux, so no good recommendation can be made. 1250 1251config CRASH_DUMP 1252 bool "kernel crash dumps" 1253 depends on X86_64 || (X86_32 && HIGHMEM) 1254 help 1255 Generate crash dump after being started by kexec. 1256 This should be normally only set in special crash dump kernels 1257 which are loaded in the main kernel with kexec-tools into 1258 a specially reserved region and then later executed after 1259 a crash by kdump/kexec. The crash dump kernel must be compiled 1260 to a memory address not used by the main kernel or BIOS using 1261 PHYSICAL_START, or it must be built as a relocatable image 1262 (CONFIG_RELOCATABLE=y). 1263 For more details see Documentation/kdump/kdump.txt 1264 1265config KEXEC_JUMP 1266 bool "kexec jump (EXPERIMENTAL)" 1267 depends on EXPERIMENTAL 1268 depends on KEXEC && HIBERNATION && X86_32 1269 help 1270 Jump between original kernel and kexeced kernel and invoke 1271 code in physical address mode via KEXEC 1272 1273config PHYSICAL_START 1274 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP) 1275 default "0x1000000" if X86_NUMAQ 1276 default "0x200000" if X86_64 1277 default "0x100000" 1278 help 1279 This gives the physical address where the kernel is loaded. 1280 1281 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1282 bzImage will decompress itself to above physical address and 1283 run from there. Otherwise, bzImage will run from the address where 1284 it has been loaded by the boot loader and will ignore above physical 1285 address. 1286 1287 In normal kdump cases one does not have to set/change this option 1288 as now bzImage can be compiled as a completely relocatable image 1289 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1290 address. This option is mainly useful for the folks who don't want 1291 to use a bzImage for capturing the crash dump and want to use a 1292 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1293 to be specifically compiled to run from a specific memory area 1294 (normally a reserved region) and this option comes handy. 1295 1296 So if you are using bzImage for capturing the crash dump, leave 1297 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y. 1298 Otherwise if you plan to use vmlinux for capturing the crash dump 1299 change this value to start of the reserved region (Typically 16MB 1300 0x1000000). In other words, it can be set based on the "X" value as 1301 specified in the "crashkernel=YM@XM" command line boot parameter 1302 passed to the panic-ed kernel. Typically this parameter is set as 1303 crashkernel=64M@16M. Please take a look at 1304 Documentation/kdump/kdump.txt for more details about crash dumps. 1305 1306 Usage of bzImage for capturing the crash dump is recommended as 1307 one does not have to build two kernels. Same kernel can be used 1308 as production kernel and capture kernel. Above option should have 1309 gone away after relocatable bzImage support is introduced. But it 1310 is present because there are users out there who continue to use 1311 vmlinux for dump capture. This option should go away down the 1312 line. 1313 1314 Don't change this unless you know what you are doing. 1315 1316config RELOCATABLE 1317 bool "Build a relocatable kernel (EXPERIMENTAL)" 1318 depends on EXPERIMENTAL 1319 help 1320 This builds a kernel image that retains relocation information 1321 so it can be loaded someplace besides the default 1MB. 1322 The relocations tend to make the kernel binary about 10% larger, 1323 but are discarded at runtime. 1324 1325 One use is for the kexec on panic case where the recovery kernel 1326 must live at a different physical address than the primary 1327 kernel. 1328 1329 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1330 it has been loaded at and the compile time physical address 1331 (CONFIG_PHYSICAL_START) is ignored. 1332 1333config PHYSICAL_ALIGN 1334 hex 1335 prompt "Alignment value to which kernel should be aligned" if X86_32 1336 default "0x100000" if X86_32 1337 default "0x200000" if X86_64 1338 range 0x2000 0x400000 1339 help 1340 This value puts the alignment restrictions on physical address 1341 where kernel is loaded and run from. Kernel is compiled for an 1342 address which meets above alignment restriction. 1343 1344 If bootloader loads the kernel at a non-aligned address and 1345 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1346 address aligned to above value and run from there. 1347 1348 If bootloader loads the kernel at a non-aligned address and 1349 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1350 load address and decompress itself to the address it has been 1351 compiled for and run from there. The address for which kernel is 1352 compiled already meets above alignment restrictions. Hence the 1353 end result is that kernel runs from a physical address meeting 1354 above alignment restrictions. 1355 1356 Don't change this unless you know what you are doing. 1357 1358config HOTPLUG_CPU 1359 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)" 1360 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER 1361 ---help--- 1362 Say Y here to experiment with turning CPUs off and on, and to 1363 enable suspend on SMP systems. CPUs can be controlled through 1364 /sys/devices/system/cpu. 1365 Say N if you want to disable CPU hotplug and don't need to 1366 suspend. 1367 1368config COMPAT_VDSO 1369 def_bool y 1370 prompt "Compat VDSO support" 1371 depends on X86_32 || IA32_EMULATION 1372 help 1373 Map the 32-bit VDSO to the predictable old-style address too. 1374 ---help--- 1375 Say N here if you are running a sufficiently recent glibc 1376 version (2.3.3 or later), to remove the high-mapped 1377 VDSO mapping and to exclusively use the randomized VDSO. 1378 1379 If unsure, say Y. 1380 1381endmenu 1382 1383config ARCH_ENABLE_MEMORY_HOTPLUG 1384 def_bool y 1385 depends on X86_64 || (X86_32 && HIGHMEM) 1386 1387config HAVE_ARCH_EARLY_PFN_TO_NID 1388 def_bool X86_64 1389 depends on NUMA 1390 1391menu "Power management options" 1392 depends on !X86_VOYAGER 1393 1394config ARCH_HIBERNATION_HEADER 1395 def_bool y 1396 depends on X86_64 && HIBERNATION 1397 1398source "kernel/power/Kconfig" 1399 1400source "drivers/acpi/Kconfig" 1401 1402config X86_APM_BOOT 1403 bool 1404 default y 1405 depends on APM || APM_MODULE 1406 1407menuconfig APM 1408 tristate "APM (Advanced Power Management) BIOS support" 1409 depends on X86_32 && PM_SLEEP 1410 ---help--- 1411 APM is a BIOS specification for saving power using several different 1412 techniques. This is mostly useful for battery powered laptops with 1413 APM compliant BIOSes. If you say Y here, the system time will be 1414 reset after a RESUME operation, the /proc/apm device will provide 1415 battery status information, and user-space programs will receive 1416 notification of APM "events" (e.g. battery status change). 1417 1418 If you select "Y" here, you can disable actual use of the APM 1419 BIOS by passing the "apm=off" option to the kernel at boot time. 1420 1421 Note that the APM support is almost completely disabled for 1422 machines with more than one CPU. 1423 1424 In order to use APM, you will need supporting software. For location 1425 and more information, read <file:Documentation/power/pm.txt> and the 1426 Battery Powered Linux mini-HOWTO, available from 1427 <http://www.tldp.org/docs.html#howto>. 1428 1429 This driver does not spin down disk drives (see the hdparm(8) 1430 manpage ("man 8 hdparm") for that), and it doesn't turn off 1431 VESA-compliant "green" monitors. 1432 1433 This driver does not support the TI 4000M TravelMate and the ACER 1434 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1435 desktop machines also don't have compliant BIOSes, and this driver 1436 may cause those machines to panic during the boot phase. 1437 1438 Generally, if you don't have a battery in your machine, there isn't 1439 much point in using this driver and you should say N. If you get 1440 random kernel OOPSes or reboots that don't seem to be related to 1441 anything, try disabling/enabling this option (or disabling/enabling 1442 APM in your BIOS). 1443 1444 Some other things you should try when experiencing seemingly random, 1445 "weird" problems: 1446 1447 1) make sure that you have enough swap space and that it is 1448 enabled. 1449 2) pass the "no-hlt" option to the kernel 1450 3) switch on floating point emulation in the kernel and pass 1451 the "no387" option to the kernel 1452 4) pass the "floppy=nodma" option to the kernel 1453 5) pass the "mem=4M" option to the kernel (thereby disabling 1454 all but the first 4 MB of RAM) 1455 6) make sure that the CPU is not over clocked. 1456 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1457 8) disable the cache from your BIOS settings 1458 9) install a fan for the video card or exchange video RAM 1459 10) install a better fan for the CPU 1460 11) exchange RAM chips 1461 12) exchange the motherboard. 1462 1463 To compile this driver as a module, choose M here: the 1464 module will be called apm. 1465 1466if APM 1467 1468config APM_IGNORE_USER_SUSPEND 1469 bool "Ignore USER SUSPEND" 1470 help 1471 This option will ignore USER SUSPEND requests. On machines with a 1472 compliant APM BIOS, you want to say N. However, on the NEC Versa M 1473 series notebooks, it is necessary to say Y because of a BIOS bug. 1474 1475config APM_DO_ENABLE 1476 bool "Enable PM at boot time" 1477 ---help--- 1478 Enable APM features at boot time. From page 36 of the APM BIOS 1479 specification: "When disabled, the APM BIOS does not automatically 1480 power manage devices, enter the Standby State, enter the Suspend 1481 State, or take power saving steps in response to CPU Idle calls." 1482 This driver will make CPU Idle calls when Linux is idle (unless this 1483 feature is turned off -- see "Do CPU IDLE calls", below). This 1484 should always save battery power, but more complicated APM features 1485 will be dependent on your BIOS implementation. You may need to turn 1486 this option off if your computer hangs at boot time when using APM 1487 support, or if it beeps continuously instead of suspending. Turn 1488 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1489 T400CDT. This is off by default since most machines do fine without 1490 this feature. 1491 1492config APM_CPU_IDLE 1493 bool "Make CPU Idle calls when idle" 1494 help 1495 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 1496 On some machines, this can activate improved power savings, such as 1497 a slowed CPU clock rate, when the machine is idle. These idle calls 1498 are made after the idle loop has run for some length of time (e.g., 1499 333 mS). On some machines, this will cause a hang at boot time or 1500 whenever the CPU becomes idle. (On machines with more than one CPU, 1501 this option does nothing.) 1502 1503config APM_DISPLAY_BLANK 1504 bool "Enable console blanking using APM" 1505 help 1506 Enable console blanking using the APM. Some laptops can use this to 1507 turn off the LCD backlight when the screen blanker of the Linux 1508 virtual console blanks the screen. Note that this is only used by 1509 the virtual console screen blanker, and won't turn off the backlight 1510 when using the X Window system. This also doesn't have anything to 1511 do with your VESA-compliant power-saving monitor. Further, this 1512 option doesn't work for all laptops -- it might not turn off your 1513 backlight at all, or it might print a lot of errors to the console, 1514 especially if you are using gpm. 1515 1516config APM_ALLOW_INTS 1517 bool "Allow interrupts during APM BIOS calls" 1518 help 1519 Normally we disable external interrupts while we are making calls to 1520 the APM BIOS as a measure to lessen the effects of a badly behaving 1521 BIOS implementation. The BIOS should reenable interrupts if it 1522 needs to. Unfortunately, some BIOSes do not -- especially those in 1523 many of the newer IBM Thinkpads. If you experience hangs when you 1524 suspend, try setting this to Y. Otherwise, say N. 1525 1526config APM_REAL_MODE_POWER_OFF 1527 bool "Use real mode APM BIOS call to power off" 1528 help 1529 Use real mode APM BIOS calls to switch off the computer. This is 1530 a work-around for a number of buggy BIOSes. Switch this option on if 1531 your computer crashes instead of powering off properly. 1532 1533endif # APM 1534 1535source "arch/x86/kernel/cpu/cpufreq/Kconfig" 1536 1537source "drivers/cpuidle/Kconfig" 1538 1539endmenu 1540 1541 1542menu "Bus options (PCI etc.)" 1543 1544config PCI 1545 bool "PCI support" 1546 default y 1547 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC) 1548 help 1549 Find out whether you have a PCI motherboard. PCI is the name of a 1550 bus system, i.e. the way the CPU talks to the other stuff inside 1551 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 1552 VESA. If you have PCI, say Y, otherwise N. 1553 1554choice 1555 prompt "PCI access mode" 1556 depends on X86_32 && PCI 1557 default PCI_GOANY 1558 ---help--- 1559 On PCI systems, the BIOS can be used to detect the PCI devices and 1560 determine their configuration. However, some old PCI motherboards 1561 have BIOS bugs and may crash if this is done. Also, some embedded 1562 PCI-based systems don't have any BIOS at all. Linux can also try to 1563 detect the PCI hardware directly without using the BIOS. 1564 1565 With this option, you can specify how Linux should detect the 1566 PCI devices. If you choose "BIOS", the BIOS will be used, 1567 if you choose "Direct", the BIOS won't be used, and if you 1568 choose "MMConfig", then PCI Express MMCONFIG will be used. 1569 If you choose "Any", the kernel will try MMCONFIG, then the 1570 direct access method and falls back to the BIOS if that doesn't 1571 work. If unsure, go with the default, which is "Any". 1572 1573config PCI_GOBIOS 1574 bool "BIOS" 1575 1576config PCI_GOMMCONFIG 1577 bool "MMConfig" 1578 1579config PCI_GODIRECT 1580 bool "Direct" 1581 1582config PCI_GOOLPC 1583 bool "OLPC" 1584 depends on OLPC 1585 1586config PCI_GOANY 1587 bool "Any" 1588 1589endchoice 1590 1591config PCI_BIOS 1592 def_bool y 1593 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 1594 1595# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 1596config PCI_DIRECT 1597 def_bool y 1598 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC)) 1599 1600config PCI_MMCONFIG 1601 def_bool y 1602 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY) 1603 1604config PCI_OLPC 1605 def_bool y 1606 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 1607 1608config PCI_DOMAINS 1609 def_bool y 1610 depends on PCI 1611 1612config PCI_MMCONFIG 1613 bool "Support mmconfig PCI config space access" 1614 depends on X86_64 && PCI && ACPI 1615 1616config DMAR 1617 bool "Support for DMA Remapping Devices (EXPERIMENTAL)" 1618 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL 1619 help 1620 DMA remapping (DMAR) devices support enables independent address 1621 translations for Direct Memory Access (DMA) from devices. 1622 These DMA remapping devices are reported via ACPI tables 1623 and include PCI device scope covered by these DMA 1624 remapping devices. 1625 1626config DMAR_GFX_WA 1627 def_bool y 1628 prompt "Support for Graphics workaround" 1629 depends on DMAR 1630 help 1631 Current Graphics drivers tend to use physical address 1632 for DMA and avoid using DMA APIs. Setting this config 1633 option permits the IOMMU driver to set a unity map for 1634 all the OS-visible memory. Hence the driver can continue 1635 to use physical addresses for DMA. 1636 1637config DMAR_FLOPPY_WA 1638 def_bool y 1639 depends on DMAR 1640 help 1641 Floppy disk drivers are know to bypass DMA API calls 1642 thereby failing to work when IOMMU is enabled. This 1643 workaround will setup a 1:1 mapping for the first 1644 16M to make floppy (an ISA device) work. 1645 1646source "drivers/pci/pcie/Kconfig" 1647 1648source "drivers/pci/Kconfig" 1649 1650# x86_64 have no ISA slots, but do have ISA-style DMA. 1651config ISA_DMA_API 1652 def_bool y 1653 1654if X86_32 1655 1656config ISA 1657 bool "ISA support" 1658 depends on !X86_VOYAGER 1659 help 1660 Find out whether you have ISA slots on your motherboard. ISA is the 1661 name of a bus system, i.e. the way the CPU talks to the other stuff 1662 inside your box. Other bus systems are PCI, EISA, MicroChannel 1663 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 1664 newer boards don't support it. If you have ISA, say Y, otherwise N. 1665 1666config EISA 1667 bool "EISA support" 1668 depends on ISA 1669 ---help--- 1670 The Extended Industry Standard Architecture (EISA) bus was 1671 developed as an open alternative to the IBM MicroChannel bus. 1672 1673 The EISA bus provided some of the features of the IBM MicroChannel 1674 bus while maintaining backward compatibility with cards made for 1675 the older ISA bus. The EISA bus saw limited use between 1988 and 1676 1995 when it was made obsolete by the PCI bus. 1677 1678 Say Y here if you are building a kernel for an EISA-based machine. 1679 1680 Otherwise, say N. 1681 1682source "drivers/eisa/Kconfig" 1683 1684config MCA 1685 bool "MCA support" if !X86_VOYAGER 1686 default y if X86_VOYAGER 1687 help 1688 MicroChannel Architecture is found in some IBM PS/2 machines and 1689 laptops. It is a bus system similar to PCI or ISA. See 1690 <file:Documentation/mca.txt> (and especially the web page given 1691 there) before attempting to build an MCA bus kernel. 1692 1693source "drivers/mca/Kconfig" 1694 1695config SCx200 1696 tristate "NatSemi SCx200 support" 1697 depends on !X86_VOYAGER 1698 help 1699 This provides basic support for National Semiconductor's 1700 (now AMD's) Geode processors. The driver probes for the 1701 PCI-IDs of several on-chip devices, so its a good dependency 1702 for other scx200_* drivers. 1703 1704 If compiled as a module, the driver is named scx200. 1705 1706config SCx200HR_TIMER 1707 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 1708 depends on SCx200 && GENERIC_TIME 1709 default y 1710 help 1711 This driver provides a clocksource built upon the on-chip 1712 27MHz high-resolution timer. Its also a workaround for 1713 NSC Geode SC-1100's buggy TSC, which loses time when the 1714 processor goes idle (as is done by the scheduler). The 1715 other workaround is idle=poll boot option. 1716 1717config GEODE_MFGPT_TIMER 1718 def_bool y 1719 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events" 1720 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS 1721 help 1722 This driver provides a clock event source based on the MFGPT 1723 timer(s) in the CS5535 and CS5536 companion chip for the geode. 1724 MFGPTs have a better resolution and max interval than the 1725 generic PIT, and are suitable for use as high-res timers. 1726 1727config OLPC 1728 bool "One Laptop Per Child support" 1729 default n 1730 help 1731 Add support for detecting the unique features of the OLPC 1732 XO hardware. 1733 1734endif # X86_32 1735 1736config K8_NB 1737 def_bool y 1738 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA))) 1739 1740source "drivers/pcmcia/Kconfig" 1741 1742source "drivers/pci/hotplug/Kconfig" 1743 1744endmenu 1745 1746 1747menu "Executable file formats / Emulations" 1748 1749source "fs/Kconfig.binfmt" 1750 1751config IA32_EMULATION 1752 bool "IA32 Emulation" 1753 depends on X86_64 1754 select COMPAT_BINFMT_ELF 1755 help 1756 Include code to run 32-bit programs under a 64-bit kernel. You should 1757 likely turn this on, unless you're 100% sure that you don't have any 1758 32-bit programs left. 1759 1760config IA32_AOUT 1761 tristate "IA32 a.out support" 1762 depends on IA32_EMULATION && ARCH_SUPPORTS_AOUT 1763 help 1764 Support old a.out binaries in the 32bit emulation. 1765 1766config COMPAT 1767 def_bool y 1768 depends on IA32_EMULATION 1769 1770config COMPAT_FOR_U64_ALIGNMENT 1771 def_bool COMPAT 1772 depends on X86_64 1773 1774config SYSVIPC_COMPAT 1775 def_bool y 1776 depends on X86_64 && COMPAT && SYSVIPC 1777 1778endmenu 1779 1780 1781source "net/Kconfig" 1782 1783source "drivers/Kconfig" 1784 1785source "drivers/firmware/Kconfig" 1786 1787source "fs/Kconfig" 1788 1789source "arch/x86/Kconfig.debug" 1790 1791source "security/Kconfig" 1792 1793source "crypto/Kconfig" 1794 1795source "arch/x86/kvm/Kconfig" 1796 1797source "lib/Kconfig" 1798