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 22config GENERIC_LOCKBREAK 23 def_bool n 24 25config GENERIC_TIME 26 def_bool y 27 28config GENERIC_CMOS_UPDATE 29 def_bool y 30 31config CLOCKSOURCE_WATCHDOG 32 def_bool y 33 34config GENERIC_CLOCKEVENTS 35 def_bool y 36 37config GENERIC_CLOCKEVENTS_BROADCAST 38 def_bool y 39 depends on X86_64 || (X86_32 && X86_LOCAL_APIC) 40 41config LOCKDEP_SUPPORT 42 def_bool y 43 44config STACKTRACE_SUPPORT 45 def_bool y 46 47config HAVE_LATENCYTOP_SUPPORT 48 def_bool y 49 50config SEMAPHORE_SLEEPERS 51 def_bool y 52 53config MMU 54 def_bool y 55 56config ZONE_DMA 57 def_bool y 58 59config QUICKLIST 60 def_bool X86_32 61 62config SBUS 63 bool 64 65config GENERIC_ISA_DMA 66 def_bool y 67 68config GENERIC_IOMAP 69 def_bool y 70 71config GENERIC_BUG 72 def_bool y 73 depends on BUG 74 75config GENERIC_HWEIGHT 76 def_bool y 77 78config GENERIC_GPIO 79 def_bool n 80 81config ARCH_MAY_HAVE_PC_FDC 82 def_bool y 83 84config DMI 85 def_bool y 86 87config RWSEM_GENERIC_SPINLOCK 88 def_bool !X86_XADD 89 90config RWSEM_XCHGADD_ALGORITHM 91 def_bool X86_XADD 92 93config ARCH_HAS_ILOG2_U32 94 def_bool n 95 96config ARCH_HAS_ILOG2_U64 97 def_bool n 98 99config GENERIC_CALIBRATE_DELAY 100 def_bool y 101 102config GENERIC_TIME_VSYSCALL 103 bool 104 default X86_64 105 106config HAVE_SETUP_PER_CPU_AREA 107 def_bool X86_64 108 109config ARCH_SUPPORTS_OPROFILE 110 bool 111 default y 112 113select HAVE_KVM 114 115config ARCH_HIBERNATION_POSSIBLE 116 def_bool y 117 depends on !SMP || !X86_VOYAGER 118 119config ARCH_SUSPEND_POSSIBLE 120 def_bool y 121 depends on !X86_VOYAGER 122 123config ZONE_DMA32 124 bool 125 default X86_64 126 127config ARCH_POPULATES_NODE_MAP 128 def_bool y 129 130config AUDIT_ARCH 131 bool 132 default X86_64 133 134# Use the generic interrupt handling code in kernel/irq/: 135config GENERIC_HARDIRQS 136 bool 137 default y 138 139config GENERIC_IRQ_PROBE 140 bool 141 default y 142 143config GENERIC_PENDING_IRQ 144 bool 145 depends on GENERIC_HARDIRQS && SMP 146 default y 147 148config X86_SMP 149 bool 150 depends on SMP && ((X86_32 && !X86_VOYAGER) || X86_64) 151 default y 152 153config X86_32_SMP 154 def_bool y 155 depends on X86_32 && SMP 156 157config X86_64_SMP 158 def_bool y 159 depends on X86_64 && SMP 160 161config X86_HT 162 bool 163 depends on SMP 164 depends on (X86_32 && !(X86_VISWS || X86_VOYAGER)) || (X86_64 && !MK8) 165 default y 166 167config X86_BIOS_REBOOT 168 bool 169 depends on X86_32 && !(X86_VISWS || X86_VOYAGER) 170 default y 171 172config X86_TRAMPOLINE 173 bool 174 depends on X86_SMP || (X86_VOYAGER && SMP) 175 default y 176 177config KTIME_SCALAR 178 def_bool X86_32 179source "init/Kconfig" 180 181menu "Processor type and features" 182 183source "kernel/time/Kconfig" 184 185config SMP 186 bool "Symmetric multi-processing support" 187 ---help--- 188 This enables support for systems with more than one CPU. If you have 189 a system with only one CPU, like most personal computers, say N. If 190 you have a system with more than one CPU, say Y. 191 192 If you say N here, the kernel will run on single and multiprocessor 193 machines, but will use only one CPU of a multiprocessor machine. If 194 you say Y here, the kernel will run on many, but not all, 195 singleprocessor machines. On a singleprocessor machine, the kernel 196 will run faster if you say N here. 197 198 Note that if you say Y here and choose architecture "586" or 199 "Pentium" under "Processor family", the kernel will not work on 486 200 architectures. Similarly, multiprocessor kernels for the "PPro" 201 architecture may not work on all Pentium based boards. 202 203 People using multiprocessor machines who say Y here should also say 204 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 205 Management" code will be disabled if you say Y here. 206 207 See also <file:Documentation/i386/IO-APIC.txt>, 208 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 209 <http://www.tldp.org/docs.html#howto>. 210 211 If you don't know what to do here, say N. 212 213choice 214 prompt "Subarchitecture Type" 215 default X86_PC 216 217config X86_PC 218 bool "PC-compatible" 219 help 220 Choose this option if your computer is a standard PC or compatible. 221 222config X86_ELAN 223 bool "AMD Elan" 224 depends on X86_32 225 help 226 Select this for an AMD Elan processor. 227 228 Do not use this option for K6/Athlon/Opteron processors! 229 230 If unsure, choose "PC-compatible" instead. 231 232config X86_VOYAGER 233 bool "Voyager (NCR)" 234 depends on X86_32 235 select SMP if !BROKEN 236 help 237 Voyager is an MCA-based 32-way capable SMP architecture proprietary 238 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based. 239 240 *** WARNING *** 241 242 If you do not specifically know you have a Voyager based machine, 243 say N here, otherwise the kernel you build will not be bootable. 244 245config X86_NUMAQ 246 bool "NUMAQ (IBM/Sequent)" 247 select SMP 248 select NUMA 249 depends on X86_32 250 help 251 This option is used for getting Linux to run on a (IBM/Sequent) NUMA 252 multiquad box. This changes the way that processors are bootstrapped, 253 and uses Clustered Logical APIC addressing mode instead of Flat Logical. 254 You will need a new lynxer.elf file to flash your firmware with - send 255 email to <Martin.Bligh@us.ibm.com>. 256 257config X86_SUMMIT 258 bool "Summit/EXA (IBM x440)" 259 depends on X86_32 && SMP 260 help 261 This option is needed for IBM systems that use the Summit/EXA chipset. 262 In particular, it is needed for the x440. 263 264 If you don't have one of these computers, you should say N here. 265 If you want to build a NUMA kernel, you must select ACPI. 266 267config X86_BIGSMP 268 bool "Support for other sub-arch SMP systems with more than 8 CPUs" 269 depends on X86_32 && SMP 270 help 271 This option is needed for the systems that have more than 8 CPUs 272 and if the system is not of any sub-arch type above. 273 274 If you don't have such a system, you should say N here. 275 276config X86_VISWS 277 bool "SGI 320/540 (Visual Workstation)" 278 depends on X86_32 279 help 280 The SGI Visual Workstation series is an IA32-based workstation 281 based on SGI systems chips with some legacy PC hardware attached. 282 283 Say Y here to create a kernel to run on the SGI 320 or 540. 284 285 A kernel compiled for the Visual Workstation will not run on PCs 286 and vice versa. See <file:Documentation/sgi-visws.txt> for details. 287 288config X86_GENERICARCH 289 bool "Generic architecture (Summit, bigsmp, ES7000, default)" 290 depends on X86_32 291 help 292 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures. 293 It is intended for a generic binary kernel. 294 If you want a NUMA kernel, select ACPI. We need SRAT for NUMA. 295 296config X86_ES7000 297 bool "Support for Unisys ES7000 IA32 series" 298 depends on X86_32 && SMP 299 help 300 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is 301 supposed to run on an IA32-based Unisys ES7000 system. 302 Only choose this option if you have such a system, otherwise you 303 should say N here. 304 305config X86_RDC321X 306 bool "RDC R-321x SoC" 307 depends on X86_32 308 select M486 309 select X86_REBOOTFIXUPS 310 select GENERIC_GPIO 311 select LEDS_GPIO 312 help 313 This option is needed for RDC R-321x system-on-chip, also known 314 as R-8610-(G). 315 If you don't have one of these chips, you should say N here. 316 317config X86_VSMP 318 bool "Support for ScaleMP vSMP" 319 depends on X86_64 && PCI 320 help 321 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 322 supposed to run on these EM64T-based machines. Only choose this option 323 if you have one of these machines. 324 325endchoice 326 327config SCHED_NO_NO_OMIT_FRAME_POINTER 328 def_bool y 329 prompt "Single-depth WCHAN output" 330 depends on X86_32 331 help 332 Calculate simpler /proc/<PID>/wchan values. If this option 333 is disabled then wchan values will recurse back to the 334 caller function. This provides more accurate wchan values, 335 at the expense of slightly more scheduling overhead. 336 337 If in doubt, say "Y". 338 339menuconfig PARAVIRT_GUEST 340 bool "Paravirtualized guest support" 341 help 342 Say Y here to get to see options related to running Linux under 343 various hypervisors. This option alone does not add any kernel code. 344 345 If you say N, all options in this submenu will be skipped and disabled. 346 347if PARAVIRT_GUEST 348 349source "arch/x86/xen/Kconfig" 350 351config VMI 352 bool "VMI Guest support" 353 select PARAVIRT 354 depends on X86_32 355 depends on !(X86_VISWS || X86_VOYAGER) 356 help 357 VMI provides a paravirtualized interface to the VMware ESX server 358 (it could be used by other hypervisors in theory too, but is not 359 at the moment), by linking the kernel to a GPL-ed ROM module 360 provided by the hypervisor. 361 362source "arch/x86/lguest/Kconfig" 363 364config PARAVIRT 365 bool "Enable paravirtualization code" 366 depends on !(X86_VISWS || X86_VOYAGER) 367 help 368 This changes the kernel so it can modify itself when it is run 369 under a hypervisor, potentially improving performance significantly 370 over full virtualization. However, when run without a hypervisor 371 the kernel is theoretically slower and slightly larger. 372 373endif 374 375config ACPI_SRAT 376 def_bool y 377 depends on X86_32 && ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH) 378 select ACPI_NUMA 379 380config HAVE_ARCH_PARSE_SRAT 381 def_bool y 382 depends on ACPI_SRAT 383 384config X86_SUMMIT_NUMA 385 def_bool y 386 depends on X86_32 && NUMA && (X86_SUMMIT || X86_GENERICARCH) 387 388config X86_CYCLONE_TIMER 389 def_bool y 390 depends on X86_32 && X86_SUMMIT || X86_GENERICARCH 391 392config ES7000_CLUSTERED_APIC 393 def_bool y 394 depends on SMP && X86_ES7000 && MPENTIUMIII 395 396source "arch/x86/Kconfig.cpu" 397 398config HPET_TIMER 399 def_bool X86_64 400 prompt "HPET Timer Support" if X86_32 401 help 402 Use the IA-PC HPET (High Precision Event Timer) to manage 403 time in preference to the PIT and RTC, if a HPET is 404 present. 405 HPET is the next generation timer replacing legacy 8254s. 406 The HPET provides a stable time base on SMP 407 systems, unlike the TSC, but it is more expensive to access, 408 as it is off-chip. You can find the HPET spec at 409 <http://www.intel.com/hardwaredesign/hpetspec.htm>. 410 411 You can safely choose Y here. However, HPET will only be 412 activated if the platform and the BIOS support this feature. 413 Otherwise the 8254 will be used for timing services. 414 415 Choose N to continue using the legacy 8254 timer. 416 417config HPET_EMULATE_RTC 418 def_bool y 419 depends on HPET_TIMER && (RTC=y || RTC=m) 420 421# Mark as embedded because too many people got it wrong. 422# The code disables itself when not needed. 423config GART_IOMMU 424 bool "GART IOMMU support" if EMBEDDED 425 default y 426 select SWIOTLB 427 select AGP 428 depends on X86_64 && PCI 429 help 430 Support for full DMA access of devices with 32bit memory access only 431 on systems with more than 3GB. This is usually needed for USB, 432 sound, many IDE/SATA chipsets and some other devices. 433 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART 434 based hardware IOMMU and a software bounce buffer based IOMMU used 435 on Intel systems and as fallback. 436 The code is only active when needed (enough memory and limited 437 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified 438 too. 439 440config CALGARY_IOMMU 441 bool "IBM Calgary IOMMU support" 442 select SWIOTLB 443 depends on X86_64 && PCI && EXPERIMENTAL 444 help 445 Support for hardware IOMMUs in IBM's xSeries x366 and x460 446 systems. Needed to run systems with more than 3GB of memory 447 properly with 32-bit PCI devices that do not support DAC 448 (Double Address Cycle). Calgary also supports bus level 449 isolation, where all DMAs pass through the IOMMU. This 450 prevents them from going anywhere except their intended 451 destination. This catches hard-to-find kernel bugs and 452 mis-behaving drivers and devices that do not use the DMA-API 453 properly to set up their DMA buffers. The IOMMU can be 454 turned off at boot time with the iommu=off parameter. 455 Normally the kernel will make the right choice by itself. 456 If unsure, say Y. 457 458config CALGARY_IOMMU_ENABLED_BY_DEFAULT 459 def_bool y 460 prompt "Should Calgary be enabled by default?" 461 depends on CALGARY_IOMMU 462 help 463 Should Calgary be enabled by default? if you choose 'y', Calgary 464 will be used (if it exists). If you choose 'n', Calgary will not be 465 used even if it exists. If you choose 'n' and would like to use 466 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 467 If unsure, say Y. 468 469# need this always selected by IOMMU for the VIA workaround 470config SWIOTLB 471 bool 472 help 473 Support for software bounce buffers used on x86-64 systems 474 which don't have a hardware IOMMU (e.g. the current generation 475 of Intel's x86-64 CPUs). Using this PCI devices which can only 476 access 32-bits of memory can be used on systems with more than 477 3 GB of memory. If unsure, say Y. 478 479 480config NR_CPUS 481 int "Maximum number of CPUs (2-255)" 482 range 2 255 483 depends on SMP 484 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000 485 default "8" 486 help 487 This allows you to specify the maximum number of CPUs which this 488 kernel will support. The maximum supported value is 255 and the 489 minimum value which makes sense is 2. 490 491 This is purely to save memory - each supported CPU adds 492 approximately eight kilobytes to the kernel image. 493 494config SCHED_SMT 495 bool "SMT (Hyperthreading) scheduler support" 496 depends on (X86_64 && SMP) || (X86_32 && X86_HT) 497 help 498 SMT scheduler support improves the CPU scheduler's decision making 499 when dealing with Intel Pentium 4 chips with HyperThreading at a 500 cost of slightly increased overhead in some places. If unsure say 501 N here. 502 503config SCHED_MC 504 def_bool y 505 prompt "Multi-core scheduler support" 506 depends on (X86_64 && SMP) || (X86_32 && X86_HT) 507 help 508 Multi-core scheduler support improves the CPU scheduler's decision 509 making when dealing with multi-core CPU chips at a cost of slightly 510 increased overhead in some places. If unsure say N here. 511 512source "kernel/Kconfig.preempt" 513 514config X86_UP_APIC 515 bool "Local APIC support on uniprocessors" 516 depends on X86_32 && !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH) 517 help 518 A local APIC (Advanced Programmable Interrupt Controller) is an 519 integrated interrupt controller in the CPU. If you have a single-CPU 520 system which has a processor with a local APIC, you can say Y here to 521 enable and use it. If you say Y here even though your machine doesn't 522 have a local APIC, then the kernel will still run with no slowdown at 523 all. The local APIC supports CPU-generated self-interrupts (timer, 524 performance counters), and the NMI watchdog which detects hard 525 lockups. 526 527config X86_UP_IOAPIC 528 bool "IO-APIC support on uniprocessors" 529 depends on X86_UP_APIC 530 help 531 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 532 SMP-capable replacement for PC-style interrupt controllers. Most 533 SMP systems and many recent uniprocessor systems have one. 534 535 If you have a single-CPU system with an IO-APIC, you can say Y here 536 to use it. If you say Y here even though your machine doesn't have 537 an IO-APIC, then the kernel will still run with no slowdown at all. 538 539config X86_LOCAL_APIC 540 def_bool y 541 depends on X86_64 || (X86_32 && (X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH)) 542 543config X86_IO_APIC 544 def_bool y 545 depends on X86_64 || (X86_32 && (X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH)) 546 547config X86_VISWS_APIC 548 def_bool y 549 depends on X86_32 && X86_VISWS 550 551config X86_MCE 552 bool "Machine Check Exception" 553 depends on !X86_VOYAGER 554 ---help--- 555 Machine Check Exception support allows the processor to notify the 556 kernel if it detects a problem (e.g. overheating, component failure). 557 The action the kernel takes depends on the severity of the problem, 558 ranging from a warning message on the console, to halting the machine. 559 Your processor must be a Pentium or newer to support this - check the 560 flags in /proc/cpuinfo for mce. Note that some older Pentium systems 561 have a design flaw which leads to false MCE events - hence MCE is 562 disabled on all P5 processors, unless explicitly enabled with "mce" 563 as a boot argument. Similarly, if MCE is built in and creates a 564 problem on some new non-standard machine, you can boot with "nomce" 565 to disable it. MCE support simply ignores non-MCE processors like 566 the 386 and 486, so nearly everyone can say Y here. 567 568config X86_MCE_INTEL 569 def_bool y 570 prompt "Intel MCE features" 571 depends on X86_64 && X86_MCE && X86_LOCAL_APIC 572 help 573 Additional support for intel specific MCE features such as 574 the thermal monitor. 575 576config X86_MCE_AMD 577 def_bool y 578 prompt "AMD MCE features" 579 depends on X86_64 && X86_MCE && X86_LOCAL_APIC 580 help 581 Additional support for AMD specific MCE features such as 582 the DRAM Error Threshold. 583 584config X86_MCE_NONFATAL 585 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4" 586 depends on X86_32 && X86_MCE 587 help 588 Enabling this feature starts a timer that triggers every 5 seconds which 589 will look at the machine check registers to see if anything happened. 590 Non-fatal problems automatically get corrected (but still logged). 591 Disable this if you don't want to see these messages. 592 Seeing the messages this option prints out may be indicative of dying 593 or out-of-spec (ie, overclocked) hardware. 594 This option only does something on certain CPUs. 595 (AMD Athlon/Duron and Intel Pentium 4) 596 597config X86_MCE_P4THERMAL 598 bool "check for P4 thermal throttling interrupt." 599 depends on X86_32 && X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS 600 help 601 Enabling this feature will cause a message to be printed when the P4 602 enters thermal throttling. 603 604config VM86 605 bool "Enable VM86 support" if EMBEDDED 606 default y 607 depends on X86_32 608 help 609 This option is required by programs like DOSEMU to run 16-bit legacy 610 code on X86 processors. It also may be needed by software like 611 XFree86 to initialize some video cards via BIOS. Disabling this 612 option saves about 6k. 613 614config TOSHIBA 615 tristate "Toshiba Laptop support" 616 depends on X86_32 617 ---help--- 618 This adds a driver to safely access the System Management Mode of 619 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 620 not work on models with a Phoenix BIOS. The System Management Mode 621 is used to set the BIOS and power saving options on Toshiba portables. 622 623 For information on utilities to make use of this driver see the 624 Toshiba Linux utilities web site at: 625 <http://www.buzzard.org.uk/toshiba/>. 626 627 Say Y if you intend to run this kernel on a Toshiba portable. 628 Say N otherwise. 629 630config I8K 631 tristate "Dell laptop support" 632 depends on X86_32 633 ---help--- 634 This adds a driver to safely access the System Management Mode 635 of the CPU on the Dell Inspiron 8000. The System Management Mode 636 is used to read cpu temperature and cooling fan status and to 637 control the fans on the I8K portables. 638 639 This driver has been tested only on the Inspiron 8000 but it may 640 also work with other Dell laptops. You can force loading on other 641 models by passing the parameter `force=1' to the module. Use at 642 your own risk. 643 644 For information on utilities to make use of this driver see the 645 I8K Linux utilities web site at: 646 <http://people.debian.org/~dz/i8k/> 647 648 Say Y if you intend to run this kernel on a Dell Inspiron 8000. 649 Say N otherwise. 650 651config X86_REBOOTFIXUPS 652 def_bool n 653 prompt "Enable X86 board specific fixups for reboot" 654 depends on X86_32 && X86 655 ---help--- 656 This enables chipset and/or board specific fixups to be done 657 in order to get reboot to work correctly. This is only needed on 658 some combinations of hardware and BIOS. The symptom, for which 659 this config is intended, is when reboot ends with a stalled/hung 660 system. 661 662 Currently, the only fixup is for the Geode machines using 663 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 664 665 Say Y if you want to enable the fixup. Currently, it's safe to 666 enable this option even if you don't need it. 667 Say N otherwise. 668 669config MICROCODE 670 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support" 671 select FW_LOADER 672 ---help--- 673 If you say Y here, you will be able to update the microcode on 674 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II, 675 Pentium III, Pentium 4, Xeon etc. You will obviously need the 676 actual microcode binary data itself which is not shipped with the 677 Linux kernel. 678 679 For latest news and information on obtaining all the required 680 ingredients for this driver, check: 681 <http://www.urbanmyth.org/microcode/>. 682 683 To compile this driver as a module, choose M here: the 684 module will be called microcode. 685 686config MICROCODE_OLD_INTERFACE 687 def_bool y 688 depends on MICROCODE 689 690config X86_MSR 691 tristate "/dev/cpu/*/msr - Model-specific register support" 692 help 693 This device gives privileged processes access to the x86 694 Model-Specific Registers (MSRs). It is a character device with 695 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 696 MSR accesses are directed to a specific CPU on multi-processor 697 systems. 698 699config X86_CPUID 700 tristate "/dev/cpu/*/cpuid - CPU information support" 701 help 702 This device gives processes access to the x86 CPUID instruction to 703 be executed on a specific processor. It is a character device 704 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 705 /dev/cpu/31/cpuid. 706 707choice 708 prompt "High Memory Support" 709 default HIGHMEM4G if !X86_NUMAQ 710 default HIGHMEM64G if X86_NUMAQ 711 depends on X86_32 712 713config NOHIGHMEM 714 bool "off" 715 depends on !X86_NUMAQ 716 ---help--- 717 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 718 However, the address space of 32-bit x86 processors is only 4 719 Gigabytes large. That means that, if you have a large amount of 720 physical memory, not all of it can be "permanently mapped" by the 721 kernel. The physical memory that's not permanently mapped is called 722 "high memory". 723 724 If you are compiling a kernel which will never run on a machine with 725 more than 1 Gigabyte total physical RAM, answer "off" here (default 726 choice and suitable for most users). This will result in a "3GB/1GB" 727 split: 3GB are mapped so that each process sees a 3GB virtual memory 728 space and the remaining part of the 4GB virtual memory space is used 729 by the kernel to permanently map as much physical memory as 730 possible. 731 732 If the machine has between 1 and 4 Gigabytes physical RAM, then 733 answer "4GB" here. 734 735 If more than 4 Gigabytes is used then answer "64GB" here. This 736 selection turns Intel PAE (Physical Address Extension) mode on. 737 PAE implements 3-level paging on IA32 processors. PAE is fully 738 supported by Linux, PAE mode is implemented on all recent Intel 739 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 740 then the kernel will not boot on CPUs that don't support PAE! 741 742 The actual amount of total physical memory will either be 743 auto detected or can be forced by using a kernel command line option 744 such as "mem=256M". (Try "man bootparam" or see the documentation of 745 your boot loader (lilo or loadlin) about how to pass options to the 746 kernel at boot time.) 747 748 If unsure, say "off". 749 750config HIGHMEM4G 751 bool "4GB" 752 depends on !X86_NUMAQ 753 help 754 Select this if you have a 32-bit processor and between 1 and 4 755 gigabytes of physical RAM. 756 757config HIGHMEM64G 758 bool "64GB" 759 depends on !M386 && !M486 760 select X86_PAE 761 help 762 Select this if you have a 32-bit processor and more than 4 763 gigabytes of physical RAM. 764 765endchoice 766 767choice 768 depends on EXPERIMENTAL 769 prompt "Memory split" if EMBEDDED 770 default VMSPLIT_3G 771 depends on X86_32 772 help 773 Select the desired split between kernel and user memory. 774 775 If the address range available to the kernel is less than the 776 physical memory installed, the remaining memory will be available 777 as "high memory". Accessing high memory is a little more costly 778 than low memory, as it needs to be mapped into the kernel first. 779 Note that increasing the kernel address space limits the range 780 available to user programs, making the address space there 781 tighter. Selecting anything other than the default 3G/1G split 782 will also likely make your kernel incompatible with binary-only 783 kernel modules. 784 785 If you are not absolutely sure what you are doing, leave this 786 option alone! 787 788 config VMSPLIT_3G 789 bool "3G/1G user/kernel split" 790 config VMSPLIT_3G_OPT 791 depends on !X86_PAE 792 bool "3G/1G user/kernel split (for full 1G low memory)" 793 config VMSPLIT_2G 794 bool "2G/2G user/kernel split" 795 config VMSPLIT_2G_OPT 796 depends on !X86_PAE 797 bool "2G/2G user/kernel split (for full 2G low memory)" 798 config VMSPLIT_1G 799 bool "1G/3G user/kernel split" 800endchoice 801 802config PAGE_OFFSET 803 hex 804 default 0xB0000000 if VMSPLIT_3G_OPT 805 default 0x80000000 if VMSPLIT_2G 806 default 0x78000000 if VMSPLIT_2G_OPT 807 default 0x40000000 if VMSPLIT_1G 808 default 0xC0000000 809 depends on X86_32 810 811config HIGHMEM 812 def_bool y 813 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 814 815config X86_PAE 816 def_bool n 817 prompt "PAE (Physical Address Extension) Support" 818 depends on X86_32 && !HIGHMEM4G 819 select RESOURCES_64BIT 820 help 821 PAE is required for NX support, and furthermore enables 822 larger swapspace support for non-overcommit purposes. It 823 has the cost of more pagetable lookup overhead, and also 824 consumes more pagetable space per process. 825 826# Common NUMA Features 827config NUMA 828 bool "Numa Memory Allocation and Scheduler Support (EXPERIMENTAL)" 829 depends on SMP 830 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI) && EXPERIMENTAL) 831 default n if X86_PC 832 default y if (X86_NUMAQ || X86_SUMMIT) 833 help 834 Enable NUMA (Non Uniform Memory Access) support. 835 The kernel will try to allocate memory used by a CPU on the 836 local memory controller of the CPU and add some more 837 NUMA awareness to the kernel. 838 839 For i386 this is currently highly experimental and should be only 840 used for kernel development. It might also cause boot failures. 841 For x86_64 this is recommended on all multiprocessor Opteron systems. 842 If the system is EM64T, you should say N unless your system is 843 EM64T NUMA. 844 845comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI" 846 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI) 847 848config K8_NUMA 849 def_bool y 850 prompt "Old style AMD Opteron NUMA detection" 851 depends on X86_64 && NUMA && PCI 852 help 853 Enable K8 NUMA node topology detection. You should say Y here if 854 you have a multi processor AMD K8 system. This uses an old 855 method to read the NUMA configuration directly from the builtin 856 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA 857 instead, which also takes priority if both are compiled in. 858 859config X86_64_ACPI_NUMA 860 def_bool y 861 prompt "ACPI NUMA detection" 862 depends on X86_64 && NUMA && ACPI && PCI 863 select ACPI_NUMA 864 help 865 Enable ACPI SRAT based node topology detection. 866 867config NUMA_EMU 868 bool "NUMA emulation" 869 depends on X86_64 && NUMA 870 help 871 Enable NUMA emulation. A flat machine will be split 872 into virtual nodes when booted with "numa=fake=N", where N is the 873 number of nodes. This is only useful for debugging. 874 875config NODES_SHIFT 876 int 877 range 1 15 if X86_64 878 default "6" if X86_64 879 default "4" if X86_NUMAQ 880 default "3" 881 depends on NEED_MULTIPLE_NODES 882 883config HAVE_ARCH_BOOTMEM_NODE 884 def_bool y 885 depends on X86_32 && NUMA 886 887config ARCH_HAVE_MEMORY_PRESENT 888 def_bool y 889 depends on X86_32 && DISCONTIGMEM 890 891config NEED_NODE_MEMMAP_SIZE 892 def_bool y 893 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 894 895config HAVE_ARCH_ALLOC_REMAP 896 def_bool y 897 depends on X86_32 && NUMA 898 899config ARCH_FLATMEM_ENABLE 900 def_bool y 901 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && X86_PC && !NUMA 902 903config ARCH_DISCONTIGMEM_ENABLE 904 def_bool y 905 depends on NUMA && X86_32 906 907config ARCH_DISCONTIGMEM_DEFAULT 908 def_bool y 909 depends on NUMA && X86_32 910 911config ARCH_SPARSEMEM_DEFAULT 912 def_bool y 913 depends on X86_64 914 915config ARCH_SPARSEMEM_ENABLE 916 def_bool y 917 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_PC) 918 select SPARSEMEM_STATIC if X86_32 919 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 920 921config ARCH_SELECT_MEMORY_MODEL 922 def_bool y 923 depends on ARCH_SPARSEMEM_ENABLE 924 925config ARCH_MEMORY_PROBE 926 def_bool X86_64 927 depends on MEMORY_HOTPLUG 928 929source "mm/Kconfig" 930 931config HIGHPTE 932 bool "Allocate 3rd-level pagetables from highmem" 933 depends on X86_32 && (HIGHMEM4G || HIGHMEM64G) 934 help 935 The VM uses one page table entry for each page of physical memory. 936 For systems with a lot of RAM, this can be wasteful of precious 937 low memory. Setting this option will put user-space page table 938 entries in high memory. 939 940config MATH_EMULATION 941 bool 942 prompt "Math emulation" if X86_32 943 ---help--- 944 Linux can emulate a math coprocessor (used for floating point 945 operations) if you don't have one. 486DX and Pentium processors have 946 a math coprocessor built in, 486SX and 386 do not, unless you added 947 a 487DX or 387, respectively. (The messages during boot time can 948 give you some hints here ["man dmesg"].) Everyone needs either a 949 coprocessor or this emulation. 950 951 If you don't have a math coprocessor, you need to say Y here; if you 952 say Y here even though you have a coprocessor, the coprocessor will 953 be used nevertheless. (This behavior can be changed with the kernel 954 command line option "no387", which comes handy if your coprocessor 955 is broken. Try "man bootparam" or see the documentation of your boot 956 loader (lilo or loadlin) about how to pass options to the kernel at 957 boot time.) This means that it is a good idea to say Y here if you 958 intend to use this kernel on different machines. 959 960 More information about the internals of the Linux math coprocessor 961 emulation can be found in <file:arch/x86/math-emu/README>. 962 963 If you are not sure, say Y; apart from resulting in a 66 KB bigger 964 kernel, it won't hurt. 965 966config MTRR 967 bool "MTRR (Memory Type Range Register) support" 968 ---help--- 969 On Intel P6 family processors (Pentium Pro, Pentium II and later) 970 the Memory Type Range Registers (MTRRs) may be used to control 971 processor access to memory ranges. This is most useful if you have 972 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 973 allows bus write transfers to be combined into a larger transfer 974 before bursting over the PCI/AGP bus. This can increase performance 975 of image write operations 2.5 times or more. Saying Y here creates a 976 /proc/mtrr file which may be used to manipulate your processor's 977 MTRRs. Typically the X server should use this. 978 979 This code has a reasonably generic interface so that similar 980 control registers on other processors can be easily supported 981 as well: 982 983 The Cyrix 6x86, 6x86MX and M II processors have Address Range 984 Registers (ARRs) which provide a similar functionality to MTRRs. For 985 these, the ARRs are used to emulate the MTRRs. 986 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 987 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 988 write-combining. All of these processors are supported by this code 989 and it makes sense to say Y here if you have one of them. 990 991 Saying Y here also fixes a problem with buggy SMP BIOSes which only 992 set the MTRRs for the boot CPU and not for the secondary CPUs. This 993 can lead to all sorts of problems, so it's good to say Y here. 994 995 You can safely say Y even if your machine doesn't have MTRRs, you'll 996 just add about 9 KB to your kernel. 997 998 See <file:Documentation/mtrr.txt> for more information. 999 1000config EFI 1001 def_bool n 1002 prompt "EFI runtime service support" 1003 depends on ACPI 1004 ---help--- 1005 This enables the kernel to use EFI runtime services that are 1006 available (such as the EFI variable services). 1007 1008 This option is only useful on systems that have EFI firmware. 1009 In addition, you should use the latest ELILO loader available 1010 at <http://elilo.sourceforge.net> in order to take advantage 1011 of EFI runtime services. However, even with this option, the 1012 resultant kernel should continue to boot on existing non-EFI 1013 platforms. 1014 1015config IRQBALANCE 1016 def_bool y 1017 prompt "Enable kernel irq balancing" 1018 depends on X86_32 && SMP && X86_IO_APIC 1019 help 1020 The default yes will allow the kernel to do irq load balancing. 1021 Saying no will keep the kernel from doing irq load balancing. 1022 1023config SECCOMP 1024 def_bool y 1025 prompt "Enable seccomp to safely compute untrusted bytecode" 1026 depends on PROC_FS 1027 help 1028 This kernel feature is useful for number crunching applications 1029 that may need to compute untrusted bytecode during their 1030 execution. By using pipes or other transports made available to 1031 the process as file descriptors supporting the read/write 1032 syscalls, it's possible to isolate those applications in 1033 their own address space using seccomp. Once seccomp is 1034 enabled via /proc/<pid>/seccomp, it cannot be disabled 1035 and the task is only allowed to execute a few safe syscalls 1036 defined by each seccomp mode. 1037 1038 If unsure, say Y. Only embedded should say N here. 1039 1040config CC_STACKPROTECTOR 1041 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)" 1042 depends on X86_64 && EXPERIMENTAL 1043 help 1044 This option turns on the -fstack-protector GCC feature. This 1045 feature puts, at the beginning of critical functions, a canary 1046 value on the stack just before the return address, and validates 1047 the value just before actually returning. Stack based buffer 1048 overflows (that need to overwrite this return address) now also 1049 overwrite the canary, which gets detected and the attack is then 1050 neutralized via a kernel panic. 1051 1052 This feature requires gcc version 4.2 or above, or a distribution 1053 gcc with the feature backported. Older versions are automatically 1054 detected and for those versions, this configuration option is ignored. 1055 1056config CC_STACKPROTECTOR_ALL 1057 bool "Use stack-protector for all functions" 1058 depends on CC_STACKPROTECTOR 1059 help 1060 Normally, GCC only inserts the canary value protection for 1061 functions that use large-ish on-stack buffers. By enabling 1062 this option, GCC will be asked to do this for ALL functions. 1063 1064source kernel/Kconfig.hz 1065 1066config KEXEC 1067 bool "kexec system call" 1068 help 1069 kexec is a system call that implements the ability to shutdown your 1070 current kernel, and to start another kernel. It is like a reboot 1071 but it is independent of the system firmware. And like a reboot 1072 you can start any kernel with it, not just Linux. 1073 1074 The name comes from the similarity to the exec system call. 1075 1076 It is an ongoing process to be certain the hardware in a machine 1077 is properly shutdown, so do not be surprised if this code does not 1078 initially work for you. It may help to enable device hotplugging 1079 support. As of this writing the exact hardware interface is 1080 strongly in flux, so no good recommendation can be made. 1081 1082config CRASH_DUMP 1083 bool "kernel crash dumps (EXPERIMENTAL)" 1084 depends on EXPERIMENTAL 1085 depends on X86_64 || (X86_32 && HIGHMEM) 1086 help 1087 Generate crash dump after being started by kexec. 1088 This should be normally only set in special crash dump kernels 1089 which are loaded in the main kernel with kexec-tools into 1090 a specially reserved region and then later executed after 1091 a crash by kdump/kexec. The crash dump kernel must be compiled 1092 to a memory address not used by the main kernel or BIOS using 1093 PHYSICAL_START, or it must be built as a relocatable image 1094 (CONFIG_RELOCATABLE=y). 1095 For more details see Documentation/kdump/kdump.txt 1096 1097config PHYSICAL_START 1098 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP) 1099 default "0x1000000" if X86_NUMAQ 1100 default "0x200000" if X86_64 1101 default "0x100000" 1102 help 1103 This gives the physical address where the kernel is loaded. 1104 1105 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1106 bzImage will decompress itself to above physical address and 1107 run from there. Otherwise, bzImage will run from the address where 1108 it has been loaded by the boot loader and will ignore above physical 1109 address. 1110 1111 In normal kdump cases one does not have to set/change this option 1112 as now bzImage can be compiled as a completely relocatable image 1113 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1114 address. This option is mainly useful for the folks who don't want 1115 to use a bzImage for capturing the crash dump and want to use a 1116 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1117 to be specifically compiled to run from a specific memory area 1118 (normally a reserved region) and this option comes handy. 1119 1120 So if you are using bzImage for capturing the crash dump, leave 1121 the value here unchanged to 0x100000 and set CONFIG_RELOCATABLE=y. 1122 Otherwise if you plan to use vmlinux for capturing the crash dump 1123 change this value to start of the reserved region (Typically 16MB 1124 0x1000000). In other words, it can be set based on the "X" value as 1125 specified in the "crashkernel=YM@XM" command line boot parameter 1126 passed to the panic-ed kernel. Typically this parameter is set as 1127 crashkernel=64M@16M. Please take a look at 1128 Documentation/kdump/kdump.txt for more details about crash dumps. 1129 1130 Usage of bzImage for capturing the crash dump is recommended as 1131 one does not have to build two kernels. Same kernel can be used 1132 as production kernel and capture kernel. Above option should have 1133 gone away after relocatable bzImage support is introduced. But it 1134 is present because there are users out there who continue to use 1135 vmlinux for dump capture. This option should go away down the 1136 line. 1137 1138 Don't change this unless you know what you are doing. 1139 1140config RELOCATABLE 1141 bool "Build a relocatable kernel (EXPERIMENTAL)" 1142 depends on EXPERIMENTAL 1143 help 1144 This builds a kernel image that retains relocation information 1145 so it can be loaded someplace besides the default 1MB. 1146 The relocations tend to make the kernel binary about 10% larger, 1147 but are discarded at runtime. 1148 1149 One use is for the kexec on panic case where the recovery kernel 1150 must live at a different physical address than the primary 1151 kernel. 1152 1153 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1154 it has been loaded at and the compile time physical address 1155 (CONFIG_PHYSICAL_START) is ignored. 1156 1157config PHYSICAL_ALIGN 1158 hex 1159 prompt "Alignment value to which kernel should be aligned" if X86_32 1160 default "0x100000" if X86_32 1161 default "0x200000" if X86_64 1162 range 0x2000 0x400000 1163 help 1164 This value puts the alignment restrictions on physical address 1165 where kernel is loaded and run from. Kernel is compiled for an 1166 address which meets above alignment restriction. 1167 1168 If bootloader loads the kernel at a non-aligned address and 1169 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1170 address aligned to above value and run from there. 1171 1172 If bootloader loads the kernel at a non-aligned address and 1173 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1174 load address and decompress itself to the address it has been 1175 compiled for and run from there. The address for which kernel is 1176 compiled already meets above alignment restrictions. Hence the 1177 end result is that kernel runs from a physical address meeting 1178 above alignment restrictions. 1179 1180 Don't change this unless you know what you are doing. 1181 1182config HOTPLUG_CPU 1183 bool "Support for suspend on SMP and hot-pluggable CPUs (EXPERIMENTAL)" 1184 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER 1185 ---help--- 1186 Say Y here to experiment with turning CPUs off and on, and to 1187 enable suspend on SMP systems. CPUs can be controlled through 1188 /sys/devices/system/cpu. 1189 Say N if you want to disable CPU hotplug and don't need to 1190 suspend. 1191 1192config COMPAT_VDSO 1193 def_bool y 1194 prompt "Compat VDSO support" 1195 depends on X86_32 || IA32_EMULATION 1196 help 1197 Map the 32-bit VDSO to the predictable old-style address too. 1198 ---help--- 1199 Say N here if you are running a sufficiently recent glibc 1200 version (2.3.3 or later), to remove the high-mapped 1201 VDSO mapping and to exclusively use the randomized VDSO. 1202 1203 If unsure, say Y. 1204 1205endmenu 1206 1207config ARCH_ENABLE_MEMORY_HOTPLUG 1208 def_bool y 1209 depends on X86_64 || (X86_32 && HIGHMEM) 1210 1211config HAVE_ARCH_EARLY_PFN_TO_NID 1212 def_bool X86_64 1213 depends on NUMA 1214 1215menu "Power management options" 1216 depends on !X86_VOYAGER 1217 1218config ARCH_HIBERNATION_HEADER 1219 def_bool y 1220 depends on X86_64 && HIBERNATION 1221 1222source "kernel/power/Kconfig" 1223 1224source "drivers/acpi/Kconfig" 1225 1226config X86_APM_BOOT 1227 bool 1228 default y 1229 depends on APM || APM_MODULE 1230 1231menuconfig APM 1232 tristate "APM (Advanced Power Management) BIOS support" 1233 depends on X86_32 && PM_SLEEP && !X86_VISWS 1234 ---help--- 1235 APM is a BIOS specification for saving power using several different 1236 techniques. This is mostly useful for battery powered laptops with 1237 APM compliant BIOSes. If you say Y here, the system time will be 1238 reset after a RESUME operation, the /proc/apm device will provide 1239 battery status information, and user-space programs will receive 1240 notification of APM "events" (e.g. battery status change). 1241 1242 If you select "Y" here, you can disable actual use of the APM 1243 BIOS by passing the "apm=off" option to the kernel at boot time. 1244 1245 Note that the APM support is almost completely disabled for 1246 machines with more than one CPU. 1247 1248 In order to use APM, you will need supporting software. For location 1249 and more information, read <file:Documentation/pm.txt> and the 1250 Battery Powered Linux mini-HOWTO, available from 1251 <http://www.tldp.org/docs.html#howto>. 1252 1253 This driver does not spin down disk drives (see the hdparm(8) 1254 manpage ("man 8 hdparm") for that), and it doesn't turn off 1255 VESA-compliant "green" monitors. 1256 1257 This driver does not support the TI 4000M TravelMate and the ACER 1258 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1259 desktop machines also don't have compliant BIOSes, and this driver 1260 may cause those machines to panic during the boot phase. 1261 1262 Generally, if you don't have a battery in your machine, there isn't 1263 much point in using this driver and you should say N. If you get 1264 random kernel OOPSes or reboots that don't seem to be related to 1265 anything, try disabling/enabling this option (or disabling/enabling 1266 APM in your BIOS). 1267 1268 Some other things you should try when experiencing seemingly random, 1269 "weird" problems: 1270 1271 1) make sure that you have enough swap space and that it is 1272 enabled. 1273 2) pass the "no-hlt" option to the kernel 1274 3) switch on floating point emulation in the kernel and pass 1275 the "no387" option to the kernel 1276 4) pass the "floppy=nodma" option to the kernel 1277 5) pass the "mem=4M" option to the kernel (thereby disabling 1278 all but the first 4 MB of RAM) 1279 6) make sure that the CPU is not over clocked. 1280 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1281 8) disable the cache from your BIOS settings 1282 9) install a fan for the video card or exchange video RAM 1283 10) install a better fan for the CPU 1284 11) exchange RAM chips 1285 12) exchange the motherboard. 1286 1287 To compile this driver as a module, choose M here: the 1288 module will be called apm. 1289 1290if APM 1291 1292config APM_IGNORE_USER_SUSPEND 1293 bool "Ignore USER SUSPEND" 1294 help 1295 This option will ignore USER SUSPEND requests. On machines with a 1296 compliant APM BIOS, you want to say N. However, on the NEC Versa M 1297 series notebooks, it is necessary to say Y because of a BIOS bug. 1298 1299config APM_DO_ENABLE 1300 bool "Enable PM at boot time" 1301 ---help--- 1302 Enable APM features at boot time. From page 36 of the APM BIOS 1303 specification: "When disabled, the APM BIOS does not automatically 1304 power manage devices, enter the Standby State, enter the Suspend 1305 State, or take power saving steps in response to CPU Idle calls." 1306 This driver will make CPU Idle calls when Linux is idle (unless this 1307 feature is turned off -- see "Do CPU IDLE calls", below). This 1308 should always save battery power, but more complicated APM features 1309 will be dependent on your BIOS implementation. You may need to turn 1310 this option off if your computer hangs at boot time when using APM 1311 support, or if it beeps continuously instead of suspending. Turn 1312 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1313 T400CDT. This is off by default since most machines do fine without 1314 this feature. 1315 1316config APM_CPU_IDLE 1317 bool "Make CPU Idle calls when idle" 1318 help 1319 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 1320 On some machines, this can activate improved power savings, such as 1321 a slowed CPU clock rate, when the machine is idle. These idle calls 1322 are made after the idle loop has run for some length of time (e.g., 1323 333 mS). On some machines, this will cause a hang at boot time or 1324 whenever the CPU becomes idle. (On machines with more than one CPU, 1325 this option does nothing.) 1326 1327config APM_DISPLAY_BLANK 1328 bool "Enable console blanking using APM" 1329 help 1330 Enable console blanking using the APM. Some laptops can use this to 1331 turn off the LCD backlight when the screen blanker of the Linux 1332 virtual console blanks the screen. Note that this is only used by 1333 the virtual console screen blanker, and won't turn off the backlight 1334 when using the X Window system. This also doesn't have anything to 1335 do with your VESA-compliant power-saving monitor. Further, this 1336 option doesn't work for all laptops -- it might not turn off your 1337 backlight at all, or it might print a lot of errors to the console, 1338 especially if you are using gpm. 1339 1340config APM_ALLOW_INTS 1341 bool "Allow interrupts during APM BIOS calls" 1342 help 1343 Normally we disable external interrupts while we are making calls to 1344 the APM BIOS as a measure to lessen the effects of a badly behaving 1345 BIOS implementation. The BIOS should reenable interrupts if it 1346 needs to. Unfortunately, some BIOSes do not -- especially those in 1347 many of the newer IBM Thinkpads. If you experience hangs when you 1348 suspend, try setting this to Y. Otherwise, say N. 1349 1350config APM_REAL_MODE_POWER_OFF 1351 bool "Use real mode APM BIOS call to power off" 1352 help 1353 Use real mode APM BIOS calls to switch off the computer. This is 1354 a work-around for a number of buggy BIOSes. Switch this option on if 1355 your computer crashes instead of powering off properly. 1356 1357endif # APM 1358 1359source "arch/x86/kernel/cpu/cpufreq/Kconfig" 1360 1361source "drivers/cpuidle/Kconfig" 1362 1363endmenu 1364 1365 1366menu "Bus options (PCI etc.)" 1367 1368config PCI 1369 bool "PCI support" if !X86_VISWS 1370 depends on !X86_VOYAGER 1371 default y 1372 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC) 1373 help 1374 Find out whether you have a PCI motherboard. PCI is the name of a 1375 bus system, i.e. the way the CPU talks to the other stuff inside 1376 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 1377 VESA. If you have PCI, say Y, otherwise N. 1378 1379choice 1380 prompt "PCI access mode" 1381 depends on X86_32 && PCI && !X86_VISWS 1382 default PCI_GOANY 1383 ---help--- 1384 On PCI systems, the BIOS can be used to detect the PCI devices and 1385 determine their configuration. However, some old PCI motherboards 1386 have BIOS bugs and may crash if this is done. Also, some embedded 1387 PCI-based systems don't have any BIOS at all. Linux can also try to 1388 detect the PCI hardware directly without using the BIOS. 1389 1390 With this option, you can specify how Linux should detect the 1391 PCI devices. If you choose "BIOS", the BIOS will be used, 1392 if you choose "Direct", the BIOS won't be used, and if you 1393 choose "MMConfig", then PCI Express MMCONFIG will be used. 1394 If you choose "Any", the kernel will try MMCONFIG, then the 1395 direct access method and falls back to the BIOS if that doesn't 1396 work. If unsure, go with the default, which is "Any". 1397 1398config PCI_GOBIOS 1399 bool "BIOS" 1400 1401config PCI_GOMMCONFIG 1402 bool "MMConfig" 1403 1404config PCI_GODIRECT 1405 bool "Direct" 1406 1407config PCI_GOANY 1408 bool "Any" 1409 1410endchoice 1411 1412config PCI_BIOS 1413 def_bool y 1414 depends on X86_32 && !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY) 1415 1416# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 1417config PCI_DIRECT 1418 def_bool y 1419 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY) || X86_VISWS) 1420 1421config PCI_MMCONFIG 1422 def_bool y 1423 depends on X86_32 && PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY) 1424 1425config PCI_DOMAINS 1426 def_bool y 1427 depends on PCI 1428 1429config PCI_MMCONFIG 1430 bool "Support mmconfig PCI config space access" 1431 depends on X86_64 && PCI && ACPI 1432 1433config DMAR 1434 bool "Support for DMA Remapping Devices (EXPERIMENTAL)" 1435 depends on X86_64 && PCI_MSI && ACPI && EXPERIMENTAL 1436 help 1437 DMA remapping (DMAR) devices support enables independent address 1438 translations for Direct Memory Access (DMA) from devices. 1439 These DMA remapping devices are reported via ACPI tables 1440 and include PCI device scope covered by these DMA 1441 remapping devices. 1442 1443config DMAR_GFX_WA 1444 def_bool y 1445 prompt "Support for Graphics workaround" 1446 depends on DMAR 1447 help 1448 Current Graphics drivers tend to use physical address 1449 for DMA and avoid using DMA APIs. Setting this config 1450 option permits the IOMMU driver to set a unity map for 1451 all the OS-visible memory. Hence the driver can continue 1452 to use physical addresses for DMA. 1453 1454config DMAR_FLOPPY_WA 1455 def_bool y 1456 depends on DMAR 1457 help 1458 Floppy disk drivers are know to bypass DMA API calls 1459 thereby failing to work when IOMMU is enabled. This 1460 workaround will setup a 1:1 mapping for the first 1461 16M to make floppy (an ISA device) work. 1462 1463source "drivers/pci/pcie/Kconfig" 1464 1465source "drivers/pci/Kconfig" 1466 1467# x86_64 have no ISA slots, but do have ISA-style DMA. 1468config ISA_DMA_API 1469 def_bool y 1470 1471if X86_32 1472 1473config ISA 1474 bool "ISA support" 1475 depends on !(X86_VOYAGER || X86_VISWS) 1476 help 1477 Find out whether you have ISA slots on your motherboard. ISA is the 1478 name of a bus system, i.e. the way the CPU talks to the other stuff 1479 inside your box. Other bus systems are PCI, EISA, MicroChannel 1480 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 1481 newer boards don't support it. If you have ISA, say Y, otherwise N. 1482 1483config EISA 1484 bool "EISA support" 1485 depends on ISA 1486 ---help--- 1487 The Extended Industry Standard Architecture (EISA) bus was 1488 developed as an open alternative to the IBM MicroChannel bus. 1489 1490 The EISA bus provided some of the features of the IBM MicroChannel 1491 bus while maintaining backward compatibility with cards made for 1492 the older ISA bus. The EISA bus saw limited use between 1988 and 1493 1995 when it was made obsolete by the PCI bus. 1494 1495 Say Y here if you are building a kernel for an EISA-based machine. 1496 1497 Otherwise, say N. 1498 1499source "drivers/eisa/Kconfig" 1500 1501config MCA 1502 bool "MCA support" if !(X86_VISWS || X86_VOYAGER) 1503 default y if X86_VOYAGER 1504 help 1505 MicroChannel Architecture is found in some IBM PS/2 machines and 1506 laptops. It is a bus system similar to PCI or ISA. See 1507 <file:Documentation/mca.txt> (and especially the web page given 1508 there) before attempting to build an MCA bus kernel. 1509 1510source "drivers/mca/Kconfig" 1511 1512config SCx200 1513 tristate "NatSemi SCx200 support" 1514 depends on !X86_VOYAGER 1515 help 1516 This provides basic support for National Semiconductor's 1517 (now AMD's) Geode processors. The driver probes for the 1518 PCI-IDs of several on-chip devices, so its a good dependency 1519 for other scx200_* drivers. 1520 1521 If compiled as a module, the driver is named scx200. 1522 1523config SCx200HR_TIMER 1524 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 1525 depends on SCx200 && GENERIC_TIME 1526 default y 1527 help 1528 This driver provides a clocksource built upon the on-chip 1529 27MHz high-resolution timer. Its also a workaround for 1530 NSC Geode SC-1100's buggy TSC, which loses time when the 1531 processor goes idle (as is done by the scheduler). The 1532 other workaround is idle=poll boot option. 1533 1534config GEODE_MFGPT_TIMER 1535 def_bool y 1536 prompt "Geode Multi-Function General Purpose Timer (MFGPT) events" 1537 depends on MGEODE_LX && GENERIC_TIME && GENERIC_CLOCKEVENTS 1538 help 1539 This driver provides a clock event source based on the MFGPT 1540 timer(s) in the CS5535 and CS5536 companion chip for the geode. 1541 MFGPTs have a better resolution and max interval than the 1542 generic PIT, and are suitable for use as high-res timers. 1543 1544endif # X86_32 1545 1546config K8_NB 1547 def_bool y 1548 depends on AGP_AMD64 || (X86_64 && (GART_IOMMU || (PCI && NUMA))) 1549 1550source "drivers/pcmcia/Kconfig" 1551 1552source "drivers/pci/hotplug/Kconfig" 1553 1554endmenu 1555 1556 1557menu "Executable file formats / Emulations" 1558 1559source "fs/Kconfig.binfmt" 1560 1561config IA32_EMULATION 1562 bool "IA32 Emulation" 1563 depends on X86_64 1564 select COMPAT_BINFMT_ELF 1565 help 1566 Include code to run 32-bit programs under a 64-bit kernel. You should 1567 likely turn this on, unless you're 100% sure that you don't have any 1568 32-bit programs left. 1569 1570config IA32_AOUT 1571 tristate "IA32 a.out support" 1572 depends on IA32_EMULATION 1573 help 1574 Support old a.out binaries in the 32bit emulation. 1575 1576config COMPAT 1577 def_bool y 1578 depends on IA32_EMULATION 1579 1580config COMPAT_FOR_U64_ALIGNMENT 1581 def_bool COMPAT 1582 depends on X86_64 1583 1584config SYSVIPC_COMPAT 1585 def_bool y 1586 depends on X86_64 && COMPAT && SYSVIPC 1587 1588endmenu 1589 1590 1591source "net/Kconfig" 1592 1593source "drivers/Kconfig" 1594 1595source "drivers/firmware/Kconfig" 1596 1597source "fs/Kconfig" 1598 1599source "kernel/Kconfig.instrumentation" 1600 1601source "arch/x86/Kconfig.debug" 1602 1603source "security/Kconfig" 1604 1605source "crypto/Kconfig" 1606 1607source "arch/x86/kvm/Kconfig" 1608 1609source "lib/Kconfig" 1610