1# x86 configuration 2mainmenu "Linux Kernel Configuration for x86" 3 4# Select 32 or 64 bit 5config 64BIT 6 bool "64-bit kernel" if ARCH = "x86" 7 default ARCH = "x86_64" 8 ---help--- 9 Say yes to build a 64-bit kernel - formerly known as x86_64 10 Say no to build a 32-bit kernel - formerly known as i386 11 12config X86_32 13 def_bool !64BIT 14 15config X86_64 16 def_bool 64BIT 17 18### Arch settings 19config X86 20 def_bool y 21 select HAVE_AOUT if X86_32 22 select HAVE_READQ 23 select HAVE_WRITEQ 24 select HAVE_UNSTABLE_SCHED_CLOCK 25 select HAVE_IDE 26 select HAVE_OPROFILE 27 select HAVE_PERF_EVENTS if (!M386 && !M486) 28 select HAVE_IOREMAP_PROT 29 select HAVE_KPROBES 30 select ARCH_WANT_OPTIONAL_GPIOLIB 31 select ARCH_WANT_FRAME_POINTERS 32 select HAVE_DMA_ATTRS 33 select HAVE_KRETPROBES 34 select HAVE_OPTPROBES 35 select HAVE_FTRACE_MCOUNT_RECORD 36 select HAVE_DYNAMIC_FTRACE 37 select HAVE_FUNCTION_TRACER 38 select HAVE_FUNCTION_GRAPH_TRACER 39 select HAVE_FUNCTION_GRAPH_FP_TEST 40 select HAVE_FUNCTION_TRACE_MCOUNT_TEST 41 select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE 42 select HAVE_SYSCALL_TRACEPOINTS 43 select HAVE_KVM 44 select HAVE_ARCH_KGDB 45 select HAVE_ARCH_TRACEHOOK 46 select HAVE_GENERIC_DMA_COHERENT if X86_32 47 select HAVE_EFFICIENT_UNALIGNED_ACCESS 48 select USER_STACKTRACE_SUPPORT 49 select HAVE_REGS_AND_STACK_ACCESS_API 50 select HAVE_DMA_API_DEBUG 51 select HAVE_KERNEL_GZIP 52 select HAVE_KERNEL_BZIP2 53 select HAVE_KERNEL_LZMA 54 select HAVE_KERNEL_LZO 55 select HAVE_HW_BREAKPOINT 56 select HAVE_MIXED_BREAKPOINTS_REGS 57 select PERF_EVENTS 58 select ANON_INODES 59 select HAVE_ARCH_KMEMCHECK 60 select HAVE_USER_RETURN_NOTIFIER 61 62config INSTRUCTION_DECODER 63 def_bool (KPROBES || PERF_EVENTS) 64 65config OUTPUT_FORMAT 66 string 67 default "elf32-i386" if X86_32 68 default "elf64-x86-64" if X86_64 69 70config ARCH_DEFCONFIG 71 string 72 default "arch/x86/configs/i386_defconfig" if X86_32 73 default "arch/x86/configs/x86_64_defconfig" if X86_64 74 75config GENERIC_TIME 76 def_bool y 77 78config GENERIC_CMOS_UPDATE 79 def_bool y 80 81config CLOCKSOURCE_WATCHDOG 82 def_bool y 83 84config GENERIC_CLOCKEVENTS 85 def_bool y 86 87config GENERIC_CLOCKEVENTS_BROADCAST 88 def_bool y 89 depends on X86_64 || (X86_32 && X86_LOCAL_APIC) 90 91config LOCKDEP_SUPPORT 92 def_bool y 93 94config STACKTRACE_SUPPORT 95 def_bool y 96 97config HAVE_LATENCYTOP_SUPPORT 98 def_bool y 99 100config MMU 101 def_bool y 102 103config ZONE_DMA 104 def_bool y 105 106config SBUS 107 bool 108 109config NEED_DMA_MAP_STATE 110 def_bool (X86_64 || DMAR || DMA_API_DEBUG) 111 112config NEED_SG_DMA_LENGTH 113 def_bool y 114 115config GENERIC_ISA_DMA 116 def_bool y 117 118config GENERIC_IOMAP 119 def_bool y 120 121config GENERIC_BUG 122 def_bool y 123 depends on BUG 124 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 125 126config GENERIC_BUG_RELATIVE_POINTERS 127 bool 128 129config GENERIC_HWEIGHT 130 def_bool y 131 132config GENERIC_GPIO 133 bool 134 135config ARCH_MAY_HAVE_PC_FDC 136 def_bool y 137 138config RWSEM_GENERIC_SPINLOCK 139 def_bool !X86_XADD 140 141config RWSEM_XCHGADD_ALGORITHM 142 def_bool X86_XADD 143 144config ARCH_HAS_CPU_IDLE_WAIT 145 def_bool y 146 147config GENERIC_CALIBRATE_DELAY 148 def_bool y 149 150config GENERIC_TIME_VSYSCALL 151 bool 152 default X86_64 153 154config ARCH_HAS_CPU_RELAX 155 def_bool y 156 157config ARCH_HAS_DEFAULT_IDLE 158 def_bool y 159 160config ARCH_HAS_CACHE_LINE_SIZE 161 def_bool y 162 163config HAVE_SETUP_PER_CPU_AREA 164 def_bool y 165 166config NEED_PER_CPU_EMBED_FIRST_CHUNK 167 def_bool y 168 169config NEED_PER_CPU_PAGE_FIRST_CHUNK 170 def_bool y 171 172config HAVE_CPUMASK_OF_CPU_MAP 173 def_bool X86_64_SMP 174 175config ARCH_HIBERNATION_POSSIBLE 176 def_bool y 177 178config ARCH_SUSPEND_POSSIBLE 179 def_bool y 180 181config ZONE_DMA32 182 bool 183 default X86_64 184 185config ARCH_POPULATES_NODE_MAP 186 def_bool y 187 188config AUDIT_ARCH 189 bool 190 default X86_64 191 192config ARCH_SUPPORTS_OPTIMIZED_INLINING 193 def_bool y 194 195config ARCH_SUPPORTS_DEBUG_PAGEALLOC 196 def_bool y 197 198config HAVE_EARLY_RES 199 def_bool y 200 201config HAVE_INTEL_TXT 202 def_bool y 203 depends on EXPERIMENTAL && DMAR && ACPI 204 205# Use the generic interrupt handling code in kernel/irq/: 206config GENERIC_HARDIRQS 207 def_bool y 208 209config GENERIC_HARDIRQS_NO__DO_IRQ 210 def_bool y 211 212config GENERIC_IRQ_PROBE 213 def_bool y 214 215config GENERIC_PENDING_IRQ 216 def_bool y 217 depends on GENERIC_HARDIRQS && SMP 218 219config USE_GENERIC_SMP_HELPERS 220 def_bool y 221 depends on SMP 222 223config X86_32_SMP 224 def_bool y 225 depends on X86_32 && SMP 226 227config X86_64_SMP 228 def_bool y 229 depends on X86_64 && SMP 230 231config X86_HT 232 def_bool y 233 depends on SMP 234 235config X86_TRAMPOLINE 236 def_bool y 237 depends on SMP || (64BIT && ACPI_SLEEP) 238 239config X86_32_LAZY_GS 240 def_bool y 241 depends on X86_32 && !CC_STACKPROTECTOR 242 243config ARCH_HWEIGHT_CFLAGS 244 string 245 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32 246 default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64 247 248config KTIME_SCALAR 249 def_bool X86_32 250source "init/Kconfig" 251source "kernel/Kconfig.freezer" 252 253menu "Processor type and features" 254 255source "kernel/time/Kconfig" 256 257config SMP 258 bool "Symmetric multi-processing support" 259 ---help--- 260 This enables support for systems with more than one CPU. If you have 261 a system with only one CPU, like most personal computers, say N. If 262 you have a system with more than one CPU, say Y. 263 264 If you say N here, the kernel will run on single and multiprocessor 265 machines, but will use only one CPU of a multiprocessor machine. If 266 you say Y here, the kernel will run on many, but not all, 267 singleprocessor machines. On a singleprocessor machine, the kernel 268 will run faster if you say N here. 269 270 Note that if you say Y here and choose architecture "586" or 271 "Pentium" under "Processor family", the kernel will not work on 486 272 architectures. Similarly, multiprocessor kernels for the "PPro" 273 architecture may not work on all Pentium based boards. 274 275 People using multiprocessor machines who say Y here should also say 276 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 277 Management" code will be disabled if you say Y here. 278 279 See also <file:Documentation/i386/IO-APIC.txt>, 280 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 281 <http://www.tldp.org/docs.html#howto>. 282 283 If you don't know what to do here, say N. 284 285config X86_X2APIC 286 bool "Support x2apic" 287 depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP 288 ---help--- 289 This enables x2apic support on CPUs that have this feature. 290 291 This allows 32-bit apic IDs (so it can support very large systems), 292 and accesses the local apic via MSRs not via mmio. 293 294 If you don't know what to do here, say N. 295 296config SPARSE_IRQ 297 bool "Support sparse irq numbering" 298 depends on PCI_MSI || HT_IRQ 299 ---help--- 300 This enables support for sparse irqs. This is useful for distro 301 kernels that want to define a high CONFIG_NR_CPUS value but still 302 want to have low kernel memory footprint on smaller machines. 303 304 ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread 305 out the irq_desc[] array in a more NUMA-friendly way. ) 306 307 If you don't know what to do here, say N. 308 309config NUMA_IRQ_DESC 310 def_bool y 311 depends on SPARSE_IRQ && NUMA 312 313config X86_MPPARSE 314 bool "Enable MPS table" if ACPI 315 default y 316 depends on X86_LOCAL_APIC 317 ---help--- 318 For old smp systems that do not have proper acpi support. Newer systems 319 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 320 321config X86_BIGSMP 322 bool "Support for big SMP systems with more than 8 CPUs" 323 depends on X86_32 && SMP 324 ---help--- 325 This option is needed for the systems that have more than 8 CPUs 326 327if X86_32 328config X86_EXTENDED_PLATFORM 329 bool "Support for extended (non-PC) x86 platforms" 330 default y 331 ---help--- 332 If you disable this option then the kernel will only support 333 standard PC platforms. (which covers the vast majority of 334 systems out there.) 335 336 If you enable this option then you'll be able to select support 337 for the following (non-PC) 32 bit x86 platforms: 338 AMD Elan 339 NUMAQ (IBM/Sequent) 340 RDC R-321x SoC 341 SGI 320/540 (Visual Workstation) 342 Summit/EXA (IBM x440) 343 Unisys ES7000 IA32 series 344 Moorestown MID devices 345 346 If you have one of these systems, or if you want to build a 347 generic distribution kernel, say Y here - otherwise say N. 348endif 349 350if X86_64 351config X86_EXTENDED_PLATFORM 352 bool "Support for extended (non-PC) x86 platforms" 353 default y 354 ---help--- 355 If you disable this option then the kernel will only support 356 standard PC platforms. (which covers the vast majority of 357 systems out there.) 358 359 If you enable this option then you'll be able to select support 360 for the following (non-PC) 64 bit x86 platforms: 361 ScaleMP vSMP 362 SGI Ultraviolet 363 364 If you have one of these systems, or if you want to build a 365 generic distribution kernel, say Y here - otherwise say N. 366endif 367# This is an alphabetically sorted list of 64 bit extended platforms 368# Please maintain the alphabetic order if and when there are additions 369 370config X86_VSMP 371 bool "ScaleMP vSMP" 372 select PARAVIRT 373 depends on X86_64 && PCI 374 depends on X86_EXTENDED_PLATFORM 375 ---help--- 376 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 377 supposed to run on these EM64T-based machines. Only choose this option 378 if you have one of these machines. 379 380config X86_UV 381 bool "SGI Ultraviolet" 382 depends on X86_64 383 depends on X86_EXTENDED_PLATFORM 384 depends on NUMA 385 depends on X86_X2APIC 386 ---help--- 387 This option is needed in order to support SGI Ultraviolet systems. 388 If you don't have one of these, you should say N here. 389 390# Following is an alphabetically sorted list of 32 bit extended platforms 391# Please maintain the alphabetic order if and when there are additions 392 393config X86_ELAN 394 bool "AMD Elan" 395 depends on X86_32 396 depends on X86_EXTENDED_PLATFORM 397 ---help--- 398 Select this for an AMD Elan processor. 399 400 Do not use this option for K6/Athlon/Opteron processors! 401 402 If unsure, choose "PC-compatible" instead. 403 404config X86_MRST 405 bool "Moorestown MID platform" 406 depends on PCI 407 depends on PCI_GOANY 408 depends on X86_32 409 depends on X86_EXTENDED_PLATFORM 410 depends on X86_IO_APIC 411 select APB_TIMER 412 ---help--- 413 Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin 414 Internet Device(MID) platform. Moorestown consists of two chips: 415 Lincroft (CPU core, graphics, and memory controller) and Langwell IOH. 416 Unlike standard x86 PCs, Moorestown does not have many legacy devices 417 nor standard legacy replacement devices/features. e.g. Moorestown does 418 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports. 419 420config X86_RDC321X 421 bool "RDC R-321x SoC" 422 depends on X86_32 423 depends on X86_EXTENDED_PLATFORM 424 select M486 425 select X86_REBOOTFIXUPS 426 ---help--- 427 This option is needed for RDC R-321x system-on-chip, also known 428 as R-8610-(G). 429 If you don't have one of these chips, you should say N here. 430 431config X86_32_NON_STANDARD 432 bool "Support non-standard 32-bit SMP architectures" 433 depends on X86_32 && SMP 434 depends on X86_EXTENDED_PLATFORM 435 ---help--- 436 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default 437 subarchitectures. It is intended for a generic binary kernel. 438 if you select them all, kernel will probe it one by one. and will 439 fallback to default. 440 441# Alphabetically sorted list of Non standard 32 bit platforms 442 443config X86_NUMAQ 444 bool "NUMAQ (IBM/Sequent)" 445 depends on X86_32_NON_STANDARD 446 depends on PCI 447 select NUMA 448 select X86_MPPARSE 449 ---help--- 450 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent) 451 NUMA multiquad box. This changes the way that processors are 452 bootstrapped, and uses Clustered Logical APIC addressing mode instead 453 of Flat Logical. You will need a new lynxer.elf file to flash your 454 firmware with - send email to <Martin.Bligh@us.ibm.com>. 455 456config X86_SUPPORTS_MEMORY_FAILURE 457 def_bool y 458 # MCE code calls memory_failure(): 459 depends on X86_MCE 460 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 461 depends on !X86_NUMAQ 462 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 463 depends on X86_64 || !SPARSEMEM 464 select ARCH_SUPPORTS_MEMORY_FAILURE 465 466config X86_VISWS 467 bool "SGI 320/540 (Visual Workstation)" 468 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT 469 depends on X86_32_NON_STANDARD 470 ---help--- 471 The SGI Visual Workstation series is an IA32-based workstation 472 based on SGI systems chips with some legacy PC hardware attached. 473 474 Say Y here to create a kernel to run on the SGI 320 or 540. 475 476 A kernel compiled for the Visual Workstation will run on general 477 PCs as well. See <file:Documentation/sgi-visws.txt> for details. 478 479config X86_SUMMIT 480 bool "Summit/EXA (IBM x440)" 481 depends on X86_32_NON_STANDARD 482 ---help--- 483 This option is needed for IBM systems that use the Summit/EXA chipset. 484 In particular, it is needed for the x440. 485 486config X86_ES7000 487 bool "Unisys ES7000 IA32 series" 488 depends on X86_32_NON_STANDARD && X86_BIGSMP 489 ---help--- 490 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is 491 supposed to run on an IA32-based Unisys ES7000 system. 492 493config SCHED_OMIT_FRAME_POINTER 494 def_bool y 495 prompt "Single-depth WCHAN output" 496 depends on X86 497 ---help--- 498 Calculate simpler /proc/<PID>/wchan values. If this option 499 is disabled then wchan values will recurse back to the 500 caller function. This provides more accurate wchan values, 501 at the expense of slightly more scheduling overhead. 502 503 If in doubt, say "Y". 504 505menuconfig PARAVIRT_GUEST 506 bool "Paravirtualized guest support" 507 ---help--- 508 Say Y here to get to see options related to running Linux under 509 various hypervisors. This option alone does not add any kernel code. 510 511 If you say N, all options in this submenu will be skipped and disabled. 512 513if PARAVIRT_GUEST 514 515source "arch/x86/xen/Kconfig" 516 517config VMI 518 bool "VMI Guest support (DEPRECATED)" 519 select PARAVIRT 520 depends on X86_32 521 ---help--- 522 VMI provides a paravirtualized interface to the VMware ESX server 523 (it could be used by other hypervisors in theory too, but is not 524 at the moment), by linking the kernel to a GPL-ed ROM module 525 provided by the hypervisor. 526 527 As of September 2009, VMware has started a phased retirement 528 of this feature from VMware's products. Please see 529 feature-removal-schedule.txt for details. If you are 530 planning to enable this option, please note that you cannot 531 live migrate a VMI enabled VM to a future VMware product, 532 which doesn't support VMI. So if you expect your kernel to 533 seamlessly migrate to newer VMware products, keep this 534 disabled. 535 536config KVM_CLOCK 537 bool "KVM paravirtualized clock" 538 select PARAVIRT 539 select PARAVIRT_CLOCK 540 ---help--- 541 Turning on this option will allow you to run a paravirtualized clock 542 when running over the KVM hypervisor. Instead of relying on a PIT 543 (or probably other) emulation by the underlying device model, the host 544 provides the guest with timing infrastructure such as time of day, and 545 system time 546 547config KVM_GUEST 548 bool "KVM Guest support" 549 select PARAVIRT 550 ---help--- 551 This option enables various optimizations for running under the KVM 552 hypervisor. 553 554source "arch/x86/lguest/Kconfig" 555 556config PARAVIRT 557 bool "Enable paravirtualization code" 558 ---help--- 559 This changes the kernel so it can modify itself when it is run 560 under a hypervisor, potentially improving performance significantly 561 over full virtualization. However, when run without a hypervisor 562 the kernel is theoretically slower and slightly larger. 563 564config PARAVIRT_SPINLOCKS 565 bool "Paravirtualization layer for spinlocks" 566 depends on PARAVIRT && SMP && EXPERIMENTAL 567 ---help--- 568 Paravirtualized spinlocks allow a pvops backend to replace the 569 spinlock implementation with something virtualization-friendly 570 (for example, block the virtual CPU rather than spinning). 571 572 Unfortunately the downside is an up to 5% performance hit on 573 native kernels, with various workloads. 574 575 If you are unsure how to answer this question, answer N. 576 577config PARAVIRT_CLOCK 578 bool 579 580endif 581 582config PARAVIRT_DEBUG 583 bool "paravirt-ops debugging" 584 depends on PARAVIRT && DEBUG_KERNEL 585 ---help--- 586 Enable to debug paravirt_ops internals. Specifically, BUG if 587 a paravirt_op is missing when it is called. 588 589config NO_BOOTMEM 590 default y 591 bool "Disable Bootmem code" 592 ---help--- 593 Use early_res directly instead of bootmem before slab is ready. 594 - allocator (buddy) [generic] 595 - early allocator (bootmem) [generic] 596 - very early allocator (reserve_early*()) [x86] 597 - very very early allocator (early brk model) [x86] 598 So reduce one layer between early allocator to final allocator 599 600 601config MEMTEST 602 bool "Memtest" 603 ---help--- 604 This option adds a kernel parameter 'memtest', which allows memtest 605 to be set. 606 memtest=0, mean disabled; -- default 607 memtest=1, mean do 1 test pattern; 608 ... 609 memtest=4, mean do 4 test patterns. 610 If you are unsure how to answer this question, answer N. 611 612config X86_SUMMIT_NUMA 613 def_bool y 614 depends on X86_32 && NUMA && X86_32_NON_STANDARD 615 616config X86_CYCLONE_TIMER 617 def_bool y 618 depends on X86_32_NON_STANDARD 619 620source "arch/x86/Kconfig.cpu" 621 622config HPET_TIMER 623 def_bool X86_64 624 prompt "HPET Timer Support" if X86_32 625 ---help--- 626 Use the IA-PC HPET (High Precision Event Timer) to manage 627 time in preference to the PIT and RTC, if a HPET is 628 present. 629 HPET is the next generation timer replacing legacy 8254s. 630 The HPET provides a stable time base on SMP 631 systems, unlike the TSC, but it is more expensive to access, 632 as it is off-chip. You can find the HPET spec at 633 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>. 634 635 You can safely choose Y here. However, HPET will only be 636 activated if the platform and the BIOS support this feature. 637 Otherwise the 8254 will be used for timing services. 638 639 Choose N to continue using the legacy 8254 timer. 640 641config HPET_EMULATE_RTC 642 def_bool y 643 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 644 645config APB_TIMER 646 def_bool y if MRST 647 prompt "Langwell APB Timer Support" if X86_MRST 648 help 649 APB timer is the replacement for 8254, HPET on X86 MID platforms. 650 The APBT provides a stable time base on SMP 651 systems, unlike the TSC, but it is more expensive to access, 652 as it is off-chip. APB timers are always running regardless of CPU 653 C states, they are used as per CPU clockevent device when possible. 654 655# Mark as embedded because too many people got it wrong. 656# The code disables itself when not needed. 657config DMI 658 default y 659 bool "Enable DMI scanning" if EMBEDDED 660 ---help--- 661 Enabled scanning of DMI to identify machine quirks. Say Y 662 here unless you have verified that your setup is not 663 affected by entries in the DMI blacklist. Required by PNP 664 BIOS code. 665 666config GART_IOMMU 667 bool "GART IOMMU support" if EMBEDDED 668 default y 669 select SWIOTLB 670 depends on X86_64 && PCI && K8_NB 671 ---help--- 672 Support for full DMA access of devices with 32bit memory access only 673 on systems with more than 3GB. This is usually needed for USB, 674 sound, many IDE/SATA chipsets and some other devices. 675 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART 676 based hardware IOMMU and a software bounce buffer based IOMMU used 677 on Intel systems and as fallback. 678 The code is only active when needed (enough memory and limited 679 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified 680 too. 681 682config CALGARY_IOMMU 683 bool "IBM Calgary IOMMU support" 684 select SWIOTLB 685 depends on X86_64 && PCI && EXPERIMENTAL 686 ---help--- 687 Support for hardware IOMMUs in IBM's xSeries x366 and x460 688 systems. Needed to run systems with more than 3GB of memory 689 properly with 32-bit PCI devices that do not support DAC 690 (Double Address Cycle). Calgary also supports bus level 691 isolation, where all DMAs pass through the IOMMU. This 692 prevents them from going anywhere except their intended 693 destination. This catches hard-to-find kernel bugs and 694 mis-behaving drivers and devices that do not use the DMA-API 695 properly to set up their DMA buffers. The IOMMU can be 696 turned off at boot time with the iommu=off parameter. 697 Normally the kernel will make the right choice by itself. 698 If unsure, say Y. 699 700config CALGARY_IOMMU_ENABLED_BY_DEFAULT 701 def_bool y 702 prompt "Should Calgary be enabled by default?" 703 depends on CALGARY_IOMMU 704 ---help--- 705 Should Calgary be enabled by default? if you choose 'y', Calgary 706 will be used (if it exists). If you choose 'n', Calgary will not be 707 used even if it exists. If you choose 'n' and would like to use 708 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 709 If unsure, say Y. 710 711config AMD_IOMMU 712 bool "AMD IOMMU support" 713 select SWIOTLB 714 select PCI_MSI 715 depends on X86_64 && PCI && ACPI 716 ---help--- 717 With this option you can enable support for AMD IOMMU hardware in 718 your system. An IOMMU is a hardware component which provides 719 remapping of DMA memory accesses from devices. With an AMD IOMMU you 720 can isolate the the DMA memory of different devices and protect the 721 system from misbehaving device drivers or hardware. 722 723 You can find out if your system has an AMD IOMMU if you look into 724 your BIOS for an option to enable it or if you have an IVRS ACPI 725 table. 726 727config AMD_IOMMU_STATS 728 bool "Export AMD IOMMU statistics to debugfs" 729 depends on AMD_IOMMU 730 select DEBUG_FS 731 ---help--- 732 This option enables code in the AMD IOMMU driver to collect various 733 statistics about whats happening in the driver and exports that 734 information to userspace via debugfs. 735 If unsure, say N. 736 737# need this always selected by IOMMU for the VIA workaround 738config SWIOTLB 739 def_bool y if X86_64 740 ---help--- 741 Support for software bounce buffers used on x86-64 systems 742 which don't have a hardware IOMMU (e.g. the current generation 743 of Intel's x86-64 CPUs). Using this PCI devices which can only 744 access 32-bits of memory can be used on systems with more than 745 3 GB of memory. If unsure, say Y. 746 747config IOMMU_HELPER 748 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU) 749 750config IOMMU_API 751 def_bool (AMD_IOMMU || DMAR) 752 753config MAXSMP 754 bool "Configure Maximum number of SMP Processors and NUMA Nodes" 755 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL 756 select CPUMASK_OFFSTACK 757 ---help--- 758 Configure maximum number of CPUS and NUMA Nodes for this architecture. 759 If unsure, say N. 760 761config NR_CPUS 762 int "Maximum number of CPUs" if SMP && !MAXSMP 763 range 2 8 if SMP && X86_32 && !X86_BIGSMP 764 range 2 512 if SMP && !MAXSMP 765 default "1" if !SMP 766 default "4096" if MAXSMP 767 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000) 768 default "8" if SMP 769 ---help--- 770 This allows you to specify the maximum number of CPUs which this 771 kernel will support. The maximum supported value is 512 and the 772 minimum value which makes sense is 2. 773 774 This is purely to save memory - each supported CPU adds 775 approximately eight kilobytes to the kernel image. 776 777config SCHED_SMT 778 bool "SMT (Hyperthreading) scheduler support" 779 depends on X86_HT 780 ---help--- 781 SMT scheduler support improves the CPU scheduler's decision making 782 when dealing with Intel Pentium 4 chips with HyperThreading at a 783 cost of slightly increased overhead in some places. If unsure say 784 N here. 785 786config SCHED_MC 787 def_bool y 788 prompt "Multi-core scheduler support" 789 depends on X86_HT 790 ---help--- 791 Multi-core scheduler support improves the CPU scheduler's decision 792 making when dealing with multi-core CPU chips at a cost of slightly 793 increased overhead in some places. If unsure say N here. 794 795source "kernel/Kconfig.preempt" 796 797config X86_UP_APIC 798 bool "Local APIC support on uniprocessors" 799 depends on X86_32 && !SMP && !X86_32_NON_STANDARD 800 ---help--- 801 A local APIC (Advanced Programmable Interrupt Controller) is an 802 integrated interrupt controller in the CPU. If you have a single-CPU 803 system which has a processor with a local APIC, you can say Y here to 804 enable and use it. If you say Y here even though your machine doesn't 805 have a local APIC, then the kernel will still run with no slowdown at 806 all. The local APIC supports CPU-generated self-interrupts (timer, 807 performance counters), and the NMI watchdog which detects hard 808 lockups. 809 810config X86_UP_IOAPIC 811 bool "IO-APIC support on uniprocessors" 812 depends on X86_UP_APIC 813 ---help--- 814 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 815 SMP-capable replacement for PC-style interrupt controllers. Most 816 SMP systems and many recent uniprocessor systems have one. 817 818 If you have a single-CPU system with an IO-APIC, you can say Y here 819 to use it. If you say Y here even though your machine doesn't have 820 an IO-APIC, then the kernel will still run with no slowdown at all. 821 822config X86_LOCAL_APIC 823 def_bool y 824 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC 825 826config X86_IO_APIC 827 def_bool y 828 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC 829 830config X86_VISWS_APIC 831 def_bool y 832 depends on X86_32 && X86_VISWS 833 834config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 835 bool "Reroute for broken boot IRQs" 836 depends on X86_IO_APIC 837 ---help--- 838 This option enables a workaround that fixes a source of 839 spurious interrupts. This is recommended when threaded 840 interrupt handling is used on systems where the generation of 841 superfluous "boot interrupts" cannot be disabled. 842 843 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 844 entry in the chipset's IO-APIC is masked (as, e.g. the RT 845 kernel does during interrupt handling). On chipsets where this 846 boot IRQ generation cannot be disabled, this workaround keeps 847 the original IRQ line masked so that only the equivalent "boot 848 IRQ" is delivered to the CPUs. The workaround also tells the 849 kernel to set up the IRQ handler on the boot IRQ line. In this 850 way only one interrupt is delivered to the kernel. Otherwise 851 the spurious second interrupt may cause the kernel to bring 852 down (vital) interrupt lines. 853 854 Only affects "broken" chipsets. Interrupt sharing may be 855 increased on these systems. 856 857config X86_MCE 858 bool "Machine Check / overheating reporting" 859 ---help--- 860 Machine Check support allows the processor to notify the 861 kernel if it detects a problem (e.g. overheating, data corruption). 862 The action the kernel takes depends on the severity of the problem, 863 ranging from warning messages to halting the machine. 864 865config X86_MCE_INTEL 866 def_bool y 867 prompt "Intel MCE features" 868 depends on X86_MCE && X86_LOCAL_APIC 869 ---help--- 870 Additional support for intel specific MCE features such as 871 the thermal monitor. 872 873config X86_MCE_AMD 874 def_bool y 875 prompt "AMD MCE features" 876 depends on X86_MCE && X86_LOCAL_APIC 877 ---help--- 878 Additional support for AMD specific MCE features such as 879 the DRAM Error Threshold. 880 881config X86_ANCIENT_MCE 882 bool "Support for old Pentium 5 / WinChip machine checks" 883 depends on X86_32 && X86_MCE 884 ---help--- 885 Include support for machine check handling on old Pentium 5 or WinChip 886 systems. These typically need to be enabled explicitely on the command 887 line. 888 889config X86_MCE_THRESHOLD 890 depends on X86_MCE_AMD || X86_MCE_INTEL 891 def_bool y 892 893config X86_MCE_INJECT 894 depends on X86_MCE 895 tristate "Machine check injector support" 896 ---help--- 897 Provide support for injecting machine checks for testing purposes. 898 If you don't know what a machine check is and you don't do kernel 899 QA it is safe to say n. 900 901config X86_THERMAL_VECTOR 902 def_bool y 903 depends on X86_MCE_INTEL 904 905config VM86 906 bool "Enable VM86 support" if EMBEDDED 907 default y 908 depends on X86_32 909 ---help--- 910 This option is required by programs like DOSEMU to run 16-bit legacy 911 code on X86 processors. It also may be needed by software like 912 XFree86 to initialize some video cards via BIOS. Disabling this 913 option saves about 6k. 914 915config TOSHIBA 916 tristate "Toshiba Laptop support" 917 depends on X86_32 918 ---help--- 919 This adds a driver to safely access the System Management Mode of 920 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 921 not work on models with a Phoenix BIOS. The System Management Mode 922 is used to set the BIOS and power saving options on Toshiba portables. 923 924 For information on utilities to make use of this driver see the 925 Toshiba Linux utilities web site at: 926 <http://www.buzzard.org.uk/toshiba/>. 927 928 Say Y if you intend to run this kernel on a Toshiba portable. 929 Say N otherwise. 930 931config I8K 932 tristate "Dell laptop support" 933 ---help--- 934 This adds a driver to safely access the System Management Mode 935 of the CPU on the Dell Inspiron 8000. The System Management Mode 936 is used to read cpu temperature and cooling fan status and to 937 control the fans on the I8K portables. 938 939 This driver has been tested only on the Inspiron 8000 but it may 940 also work with other Dell laptops. You can force loading on other 941 models by passing the parameter `force=1' to the module. Use at 942 your own risk. 943 944 For information on utilities to make use of this driver see the 945 I8K Linux utilities web site at: 946 <http://people.debian.org/~dz/i8k/> 947 948 Say Y if you intend to run this kernel on a Dell Inspiron 8000. 949 Say N otherwise. 950 951config X86_REBOOTFIXUPS 952 bool "Enable X86 board specific fixups for reboot" 953 depends on X86_32 954 ---help--- 955 This enables chipset and/or board specific fixups to be done 956 in order to get reboot to work correctly. This is only needed on 957 some combinations of hardware and BIOS. The symptom, for which 958 this config is intended, is when reboot ends with a stalled/hung 959 system. 960 961 Currently, the only fixup is for the Geode machines using 962 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 963 964 Say Y if you want to enable the fixup. Currently, it's safe to 965 enable this option even if you don't need it. 966 Say N otherwise. 967 968config MICROCODE 969 tristate "/dev/cpu/microcode - microcode support" 970 select FW_LOADER 971 ---help--- 972 If you say Y here, you will be able to update the microcode on 973 certain Intel and AMD processors. The Intel support is for the 974 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, 975 Pentium 4, Xeon etc. The AMD support is for family 0x10 and 976 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra. 977 You will obviously need the actual microcode binary data itself 978 which is not shipped with the Linux kernel. 979 980 This option selects the general module only, you need to select 981 at least one vendor specific module as well. 982 983 To compile this driver as a module, choose M here: the 984 module will be called microcode. 985 986config MICROCODE_INTEL 987 bool "Intel microcode patch loading support" 988 depends on MICROCODE 989 default MICROCODE 990 select FW_LOADER 991 ---help--- 992 This options enables microcode patch loading support for Intel 993 processors. 994 995 For latest news and information on obtaining all the required 996 Intel ingredients for this driver, check: 997 <http://www.urbanmyth.org/microcode/>. 998 999config MICROCODE_AMD 1000 bool "AMD microcode patch loading support" 1001 depends on MICROCODE 1002 select FW_LOADER 1003 ---help--- 1004 If you select this option, microcode patch loading support for AMD 1005 processors will be enabled. 1006 1007config MICROCODE_OLD_INTERFACE 1008 def_bool y 1009 depends on MICROCODE 1010 1011config X86_MSR 1012 tristate "/dev/cpu/*/msr - Model-specific register support" 1013 ---help--- 1014 This device gives privileged processes access to the x86 1015 Model-Specific Registers (MSRs). It is a character device with 1016 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1017 MSR accesses are directed to a specific CPU on multi-processor 1018 systems. 1019 1020config X86_CPUID 1021 tristate "/dev/cpu/*/cpuid - CPU information support" 1022 ---help--- 1023 This device gives processes access to the x86 CPUID instruction to 1024 be executed on a specific processor. It is a character device 1025 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1026 /dev/cpu/31/cpuid. 1027 1028choice 1029 prompt "High Memory Support" 1030 default HIGHMEM64G if X86_NUMAQ 1031 default HIGHMEM4G 1032 depends on X86_32 1033 1034config NOHIGHMEM 1035 bool "off" 1036 depends on !X86_NUMAQ 1037 ---help--- 1038 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1039 However, the address space of 32-bit x86 processors is only 4 1040 Gigabytes large. That means that, if you have a large amount of 1041 physical memory, not all of it can be "permanently mapped" by the 1042 kernel. The physical memory that's not permanently mapped is called 1043 "high memory". 1044 1045 If you are compiling a kernel which will never run on a machine with 1046 more than 1 Gigabyte total physical RAM, answer "off" here (default 1047 choice and suitable for most users). This will result in a "3GB/1GB" 1048 split: 3GB are mapped so that each process sees a 3GB virtual memory 1049 space and the remaining part of the 4GB virtual memory space is used 1050 by the kernel to permanently map as much physical memory as 1051 possible. 1052 1053 If the machine has between 1 and 4 Gigabytes physical RAM, then 1054 answer "4GB" here. 1055 1056 If more than 4 Gigabytes is used then answer "64GB" here. This 1057 selection turns Intel PAE (Physical Address Extension) mode on. 1058 PAE implements 3-level paging on IA32 processors. PAE is fully 1059 supported by Linux, PAE mode is implemented on all recent Intel 1060 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1061 then the kernel will not boot on CPUs that don't support PAE! 1062 1063 The actual amount of total physical memory will either be 1064 auto detected or can be forced by using a kernel command line option 1065 such as "mem=256M". (Try "man bootparam" or see the documentation of 1066 your boot loader (lilo or loadlin) about how to pass options to the 1067 kernel at boot time.) 1068 1069 If unsure, say "off". 1070 1071config HIGHMEM4G 1072 bool "4GB" 1073 depends on !X86_NUMAQ 1074 ---help--- 1075 Select this if you have a 32-bit processor and between 1 and 4 1076 gigabytes of physical RAM. 1077 1078config HIGHMEM64G 1079 bool "64GB" 1080 depends on !M386 && !M486 1081 select X86_PAE 1082 ---help--- 1083 Select this if you have a 32-bit processor and more than 4 1084 gigabytes of physical RAM. 1085 1086endchoice 1087 1088choice 1089 depends on EXPERIMENTAL 1090 prompt "Memory split" if EMBEDDED 1091 default VMSPLIT_3G 1092 depends on X86_32 1093 ---help--- 1094 Select the desired split between kernel and user memory. 1095 1096 If the address range available to the kernel is less than the 1097 physical memory installed, the remaining memory will be available 1098 as "high memory". Accessing high memory is a little more costly 1099 than low memory, as it needs to be mapped into the kernel first. 1100 Note that increasing the kernel address space limits the range 1101 available to user programs, making the address space there 1102 tighter. Selecting anything other than the default 3G/1G split 1103 will also likely make your kernel incompatible with binary-only 1104 kernel modules. 1105 1106 If you are not absolutely sure what you are doing, leave this 1107 option alone! 1108 1109 config VMSPLIT_3G 1110 bool "3G/1G user/kernel split" 1111 config VMSPLIT_3G_OPT 1112 depends on !X86_PAE 1113 bool "3G/1G user/kernel split (for full 1G low memory)" 1114 config VMSPLIT_2G 1115 bool "2G/2G user/kernel split" 1116 config VMSPLIT_2G_OPT 1117 depends on !X86_PAE 1118 bool "2G/2G user/kernel split (for full 2G low memory)" 1119 config VMSPLIT_1G 1120 bool "1G/3G user/kernel split" 1121endchoice 1122 1123config PAGE_OFFSET 1124 hex 1125 default 0xB0000000 if VMSPLIT_3G_OPT 1126 default 0x80000000 if VMSPLIT_2G 1127 default 0x78000000 if VMSPLIT_2G_OPT 1128 default 0x40000000 if VMSPLIT_1G 1129 default 0xC0000000 1130 depends on X86_32 1131 1132config HIGHMEM 1133 def_bool y 1134 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1135 1136config X86_PAE 1137 bool "PAE (Physical Address Extension) Support" 1138 depends on X86_32 && !HIGHMEM4G 1139 ---help--- 1140 PAE is required for NX support, and furthermore enables 1141 larger swapspace support for non-overcommit purposes. It 1142 has the cost of more pagetable lookup overhead, and also 1143 consumes more pagetable space per process. 1144 1145config ARCH_PHYS_ADDR_T_64BIT 1146 def_bool X86_64 || X86_PAE 1147 1148config DIRECT_GBPAGES 1149 bool "Enable 1GB pages for kernel pagetables" if EMBEDDED 1150 default y 1151 depends on X86_64 1152 ---help--- 1153 Allow the kernel linear mapping to use 1GB pages on CPUs that 1154 support it. This can improve the kernel's performance a tiny bit by 1155 reducing TLB pressure. If in doubt, say "Y". 1156 1157# Common NUMA Features 1158config NUMA 1159 bool "Numa Memory Allocation and Scheduler Support" 1160 depends on SMP 1161 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL) 1162 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP) 1163 ---help--- 1164 Enable NUMA (Non Uniform Memory Access) support. 1165 1166 The kernel will try to allocate memory used by a CPU on the 1167 local memory controller of the CPU and add some more 1168 NUMA awareness to the kernel. 1169 1170 For 64-bit this is recommended if the system is Intel Core i7 1171 (or later), AMD Opteron, or EM64T NUMA. 1172 1173 For 32-bit this is only needed on (rare) 32-bit-only platforms 1174 that support NUMA topologies, such as NUMAQ / Summit, or if you 1175 boot a 32-bit kernel on a 64-bit NUMA platform. 1176 1177 Otherwise, you should say N. 1178 1179comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI" 1180 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI) 1181 1182config K8_NUMA 1183 def_bool y 1184 prompt "Old style AMD Opteron NUMA detection" 1185 depends on X86_64 && NUMA && PCI 1186 ---help--- 1187 Enable K8 NUMA node topology detection. You should say Y here if 1188 you have a multi processor AMD K8 system. This uses an old 1189 method to read the NUMA configuration directly from the builtin 1190 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA 1191 instead, which also takes priority if both are compiled in. 1192 1193config X86_64_ACPI_NUMA 1194 def_bool y 1195 prompt "ACPI NUMA detection" 1196 depends on X86_64 && NUMA && ACPI && PCI 1197 select ACPI_NUMA 1198 ---help--- 1199 Enable ACPI SRAT based node topology detection. 1200 1201# Some NUMA nodes have memory ranges that span 1202# other nodes. Even though a pfn is valid and 1203# between a node's start and end pfns, it may not 1204# reside on that node. See memmap_init_zone() 1205# for details. 1206config NODES_SPAN_OTHER_NODES 1207 def_bool y 1208 depends on X86_64_ACPI_NUMA 1209 1210config NUMA_EMU 1211 bool "NUMA emulation" 1212 depends on X86_64 && NUMA 1213 ---help--- 1214 Enable NUMA emulation. A flat machine will be split 1215 into virtual nodes when booted with "numa=fake=N", where N is the 1216 number of nodes. This is only useful for debugging. 1217 1218config NODES_SHIFT 1219 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1220 range 1 10 1221 default "10" if MAXSMP 1222 default "6" if X86_64 1223 default "4" if X86_NUMAQ 1224 default "3" 1225 depends on NEED_MULTIPLE_NODES 1226 ---help--- 1227 Specify the maximum number of NUMA Nodes available on the target 1228 system. Increases memory reserved to accommodate various tables. 1229 1230config HAVE_ARCH_BOOTMEM 1231 def_bool y 1232 depends on X86_32 && NUMA 1233 1234config ARCH_HAVE_MEMORY_PRESENT 1235 def_bool y 1236 depends on X86_32 && DISCONTIGMEM 1237 1238config NEED_NODE_MEMMAP_SIZE 1239 def_bool y 1240 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1241 1242config HAVE_ARCH_ALLOC_REMAP 1243 def_bool y 1244 depends on X86_32 && NUMA 1245 1246config ARCH_FLATMEM_ENABLE 1247 def_bool y 1248 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA 1249 1250config ARCH_DISCONTIGMEM_ENABLE 1251 def_bool y 1252 depends on NUMA && X86_32 1253 1254config ARCH_DISCONTIGMEM_DEFAULT 1255 def_bool y 1256 depends on NUMA && X86_32 1257 1258config ARCH_PROC_KCORE_TEXT 1259 def_bool y 1260 depends on X86_64 && PROC_KCORE 1261 1262config ARCH_SPARSEMEM_DEFAULT 1263 def_bool y 1264 depends on X86_64 1265 1266config ARCH_SPARSEMEM_ENABLE 1267 def_bool y 1268 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD 1269 select SPARSEMEM_STATIC if X86_32 1270 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1271 1272config ARCH_SELECT_MEMORY_MODEL 1273 def_bool y 1274 depends on ARCH_SPARSEMEM_ENABLE 1275 1276config ARCH_MEMORY_PROBE 1277 def_bool X86_64 1278 depends on MEMORY_HOTPLUG 1279 1280config ILLEGAL_POINTER_VALUE 1281 hex 1282 default 0 if X86_32 1283 default 0xdead000000000000 if X86_64 1284 1285source "mm/Kconfig" 1286 1287config HIGHPTE 1288 bool "Allocate 3rd-level pagetables from highmem" 1289 depends on HIGHMEM 1290 ---help--- 1291 The VM uses one page table entry for each page of physical memory. 1292 For systems with a lot of RAM, this can be wasteful of precious 1293 low memory. Setting this option will put user-space page table 1294 entries in high memory. 1295 1296config X86_CHECK_BIOS_CORRUPTION 1297 bool "Check for low memory corruption" 1298 ---help--- 1299 Periodically check for memory corruption in low memory, which 1300 is suspected to be caused by BIOS. Even when enabled in the 1301 configuration, it is disabled at runtime. Enable it by 1302 setting "memory_corruption_check=1" on the kernel command 1303 line. By default it scans the low 64k of memory every 60 1304 seconds; see the memory_corruption_check_size and 1305 memory_corruption_check_period parameters in 1306 Documentation/kernel-parameters.txt to adjust this. 1307 1308 When enabled with the default parameters, this option has 1309 almost no overhead, as it reserves a relatively small amount 1310 of memory and scans it infrequently. It both detects corruption 1311 and prevents it from affecting the running system. 1312 1313 It is, however, intended as a diagnostic tool; if repeatable 1314 BIOS-originated corruption always affects the same memory, 1315 you can use memmap= to prevent the kernel from using that 1316 memory. 1317 1318config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1319 bool "Set the default setting of memory_corruption_check" 1320 depends on X86_CHECK_BIOS_CORRUPTION 1321 default y 1322 ---help--- 1323 Set whether the default state of memory_corruption_check is 1324 on or off. 1325 1326config X86_RESERVE_LOW_64K 1327 bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen" 1328 default y 1329 ---help--- 1330 Reserve the first 64K of physical RAM on BIOSes that are known 1331 to potentially corrupt that memory range. A numbers of BIOSes are 1332 known to utilize this area during suspend/resume, so it must not 1333 be used by the kernel. 1334 1335 Set this to N if you are absolutely sure that you trust the BIOS 1336 to get all its memory reservations and usages right. 1337 1338 If you have doubts about the BIOS (e.g. suspend/resume does not 1339 work or there's kernel crashes after certain hardware hotplug 1340 events) and it's not AMI or Phoenix, then you might want to enable 1341 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical 1342 corruption patterns. 1343 1344 Say Y if unsure. 1345 1346config MATH_EMULATION 1347 bool 1348 prompt "Math emulation" if X86_32 1349 ---help--- 1350 Linux can emulate a math coprocessor (used for floating point 1351 operations) if you don't have one. 486DX and Pentium processors have 1352 a math coprocessor built in, 486SX and 386 do not, unless you added 1353 a 487DX or 387, respectively. (The messages during boot time can 1354 give you some hints here ["man dmesg"].) Everyone needs either a 1355 coprocessor or this emulation. 1356 1357 If you don't have a math coprocessor, you need to say Y here; if you 1358 say Y here even though you have a coprocessor, the coprocessor will 1359 be used nevertheless. (This behavior can be changed with the kernel 1360 command line option "no387", which comes handy if your coprocessor 1361 is broken. Try "man bootparam" or see the documentation of your boot 1362 loader (lilo or loadlin) about how to pass options to the kernel at 1363 boot time.) This means that it is a good idea to say Y here if you 1364 intend to use this kernel on different machines. 1365 1366 More information about the internals of the Linux math coprocessor 1367 emulation can be found in <file:arch/x86/math-emu/README>. 1368 1369 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1370 kernel, it won't hurt. 1371 1372config MTRR 1373 def_bool y 1374 prompt "MTRR (Memory Type Range Register) support" if EMBEDDED 1375 ---help--- 1376 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1377 the Memory Type Range Registers (MTRRs) may be used to control 1378 processor access to memory ranges. This is most useful if you have 1379 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1380 allows bus write transfers to be combined into a larger transfer 1381 before bursting over the PCI/AGP bus. This can increase performance 1382 of image write operations 2.5 times or more. Saying Y here creates a 1383 /proc/mtrr file which may be used to manipulate your processor's 1384 MTRRs. Typically the X server should use this. 1385 1386 This code has a reasonably generic interface so that similar 1387 control registers on other processors can be easily supported 1388 as well: 1389 1390 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1391 Registers (ARRs) which provide a similar functionality to MTRRs. For 1392 these, the ARRs are used to emulate the MTRRs. 1393 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1394 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1395 write-combining. All of these processors are supported by this code 1396 and it makes sense to say Y here if you have one of them. 1397 1398 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1399 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1400 can lead to all sorts of problems, so it's good to say Y here. 1401 1402 You can safely say Y even if your machine doesn't have MTRRs, you'll 1403 just add about 9 KB to your kernel. 1404 1405 See <file:Documentation/x86/mtrr.txt> for more information. 1406 1407config MTRR_SANITIZER 1408 def_bool y 1409 prompt "MTRR cleanup support" 1410 depends on MTRR 1411 ---help--- 1412 Convert MTRR layout from continuous to discrete, so X drivers can 1413 add writeback entries. 1414 1415 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1416 The largest mtrr entry size for a continuous block can be set with 1417 mtrr_chunk_size. 1418 1419 If unsure, say Y. 1420 1421config MTRR_SANITIZER_ENABLE_DEFAULT 1422 int "MTRR cleanup enable value (0-1)" 1423 range 0 1 1424 default "0" 1425 depends on MTRR_SANITIZER 1426 ---help--- 1427 Enable mtrr cleanup default value 1428 1429config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1430 int "MTRR cleanup spare reg num (0-7)" 1431 range 0 7 1432 default "1" 1433 depends on MTRR_SANITIZER 1434 ---help--- 1435 mtrr cleanup spare entries default, it can be changed via 1436 mtrr_spare_reg_nr=N on the kernel command line. 1437 1438config X86_PAT 1439 def_bool y 1440 prompt "x86 PAT support" if EMBEDDED 1441 depends on MTRR 1442 ---help--- 1443 Use PAT attributes to setup page level cache control. 1444 1445 PATs are the modern equivalents of MTRRs and are much more 1446 flexible than MTRRs. 1447 1448 Say N here if you see bootup problems (boot crash, boot hang, 1449 spontaneous reboots) or a non-working video driver. 1450 1451 If unsure, say Y. 1452 1453config ARCH_USES_PG_UNCACHED 1454 def_bool y 1455 depends on X86_PAT 1456 1457config EFI 1458 bool "EFI runtime service support" 1459 depends on ACPI 1460 ---help--- 1461 This enables the kernel to use EFI runtime services that are 1462 available (such as the EFI variable services). 1463 1464 This option is only useful on systems that have EFI firmware. 1465 In addition, you should use the latest ELILO loader available 1466 at <http://elilo.sourceforge.net> in order to take advantage 1467 of EFI runtime services. However, even with this option, the 1468 resultant kernel should continue to boot on existing non-EFI 1469 platforms. 1470 1471config SECCOMP 1472 def_bool y 1473 prompt "Enable seccomp to safely compute untrusted bytecode" 1474 ---help--- 1475 This kernel feature is useful for number crunching applications 1476 that may need to compute untrusted bytecode during their 1477 execution. By using pipes or other transports made available to 1478 the process as file descriptors supporting the read/write 1479 syscalls, it's possible to isolate those applications in 1480 their own address space using seccomp. Once seccomp is 1481 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1482 and the task is only allowed to execute a few safe syscalls 1483 defined by each seccomp mode. 1484 1485 If unsure, say Y. Only embedded should say N here. 1486 1487config CC_STACKPROTECTOR 1488 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)" 1489 ---help--- 1490 This option turns on the -fstack-protector GCC feature. This 1491 feature puts, at the beginning of functions, a canary value on 1492 the stack just before the return address, and validates 1493 the value just before actually returning. Stack based buffer 1494 overflows (that need to overwrite this return address) now also 1495 overwrite the canary, which gets detected and the attack is then 1496 neutralized via a kernel panic. 1497 1498 This feature requires gcc version 4.2 or above, or a distribution 1499 gcc with the feature backported. Older versions are automatically 1500 detected and for those versions, this configuration option is 1501 ignored. (and a warning is printed during bootup) 1502 1503source kernel/Kconfig.hz 1504 1505config KEXEC 1506 bool "kexec system call" 1507 ---help--- 1508 kexec is a system call that implements the ability to shutdown your 1509 current kernel, and to start another kernel. It is like a reboot 1510 but it is independent of the system firmware. And like a reboot 1511 you can start any kernel with it, not just Linux. 1512 1513 The name comes from the similarity to the exec system call. 1514 1515 It is an ongoing process to be certain the hardware in a machine 1516 is properly shutdown, so do not be surprised if this code does not 1517 initially work for you. It may help to enable device hotplugging 1518 support. As of this writing the exact hardware interface is 1519 strongly in flux, so no good recommendation can be made. 1520 1521config CRASH_DUMP 1522 bool "kernel crash dumps" 1523 depends on X86_64 || (X86_32 && HIGHMEM) 1524 ---help--- 1525 Generate crash dump after being started by kexec. 1526 This should be normally only set in special crash dump kernels 1527 which are loaded in the main kernel with kexec-tools into 1528 a specially reserved region and then later executed after 1529 a crash by kdump/kexec. The crash dump kernel must be compiled 1530 to a memory address not used by the main kernel or BIOS using 1531 PHYSICAL_START, or it must be built as a relocatable image 1532 (CONFIG_RELOCATABLE=y). 1533 For more details see Documentation/kdump/kdump.txt 1534 1535config KEXEC_JUMP 1536 bool "kexec jump (EXPERIMENTAL)" 1537 depends on EXPERIMENTAL 1538 depends on KEXEC && HIBERNATION 1539 ---help--- 1540 Jump between original kernel and kexeced kernel and invoke 1541 code in physical address mode via KEXEC 1542 1543config PHYSICAL_START 1544 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP) 1545 default "0x1000000" 1546 ---help--- 1547 This gives the physical address where the kernel is loaded. 1548 1549 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1550 bzImage will decompress itself to above physical address and 1551 run from there. Otherwise, bzImage will run from the address where 1552 it has been loaded by the boot loader and will ignore above physical 1553 address. 1554 1555 In normal kdump cases one does not have to set/change this option 1556 as now bzImage can be compiled as a completely relocatable image 1557 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1558 address. This option is mainly useful for the folks who don't want 1559 to use a bzImage for capturing the crash dump and want to use a 1560 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1561 to be specifically compiled to run from a specific memory area 1562 (normally a reserved region) and this option comes handy. 1563 1564 So if you are using bzImage for capturing the crash dump, 1565 leave the value here unchanged to 0x1000000 and set 1566 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1567 for capturing the crash dump change this value to start of 1568 the reserved region. In other words, it can be set based on 1569 the "X" value as specified in the "crashkernel=YM@XM" 1570 command line boot parameter passed to the panic-ed 1571 kernel. Please take a look at Documentation/kdump/kdump.txt 1572 for more details about crash dumps. 1573 1574 Usage of bzImage for capturing the crash dump is recommended as 1575 one does not have to build two kernels. Same kernel can be used 1576 as production kernel and capture kernel. Above option should have 1577 gone away after relocatable bzImage support is introduced. But it 1578 is present because there are users out there who continue to use 1579 vmlinux for dump capture. This option should go away down the 1580 line. 1581 1582 Don't change this unless you know what you are doing. 1583 1584config RELOCATABLE 1585 bool "Build a relocatable kernel" 1586 default y 1587 ---help--- 1588 This builds a kernel image that retains relocation information 1589 so it can be loaded someplace besides the default 1MB. 1590 The relocations tend to make the kernel binary about 10% larger, 1591 but are discarded at runtime. 1592 1593 One use is for the kexec on panic case where the recovery kernel 1594 must live at a different physical address than the primary 1595 kernel. 1596 1597 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1598 it has been loaded at and the compile time physical address 1599 (CONFIG_PHYSICAL_START) is ignored. 1600 1601# Relocation on x86-32 needs some additional build support 1602config X86_NEED_RELOCS 1603 def_bool y 1604 depends on X86_32 && RELOCATABLE 1605 1606config PHYSICAL_ALIGN 1607 hex "Alignment value to which kernel should be aligned" if X86_32 1608 default "0x1000000" 1609 range 0x2000 0x1000000 1610 ---help--- 1611 This value puts the alignment restrictions on physical address 1612 where kernel is loaded and run from. Kernel is compiled for an 1613 address which meets above alignment restriction. 1614 1615 If bootloader loads the kernel at a non-aligned address and 1616 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1617 address aligned to above value and run from there. 1618 1619 If bootloader loads the kernel at a non-aligned address and 1620 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1621 load address and decompress itself to the address it has been 1622 compiled for and run from there. The address for which kernel is 1623 compiled already meets above alignment restrictions. Hence the 1624 end result is that kernel runs from a physical address meeting 1625 above alignment restrictions. 1626 1627 Don't change this unless you know what you are doing. 1628 1629config HOTPLUG_CPU 1630 bool "Support for hot-pluggable CPUs" 1631 depends on SMP && HOTPLUG 1632 ---help--- 1633 Say Y here to allow turning CPUs off and on. CPUs can be 1634 controlled through /sys/devices/system/cpu. 1635 ( Note: power management support will enable this option 1636 automatically on SMP systems. ) 1637 Say N if you want to disable CPU hotplug. 1638 1639config COMPAT_VDSO 1640 def_bool y 1641 prompt "Compat VDSO support" 1642 depends on X86_32 || IA32_EMULATION 1643 ---help--- 1644 Map the 32-bit VDSO to the predictable old-style address too. 1645 1646 Say N here if you are running a sufficiently recent glibc 1647 version (2.3.3 or later), to remove the high-mapped 1648 VDSO mapping and to exclusively use the randomized VDSO. 1649 1650 If unsure, say Y. 1651 1652config CMDLINE_BOOL 1653 bool "Built-in kernel command line" 1654 ---help--- 1655 Allow for specifying boot arguments to the kernel at 1656 build time. On some systems (e.g. embedded ones), it is 1657 necessary or convenient to provide some or all of the 1658 kernel boot arguments with the kernel itself (that is, 1659 to not rely on the boot loader to provide them.) 1660 1661 To compile command line arguments into the kernel, 1662 set this option to 'Y', then fill in the 1663 the boot arguments in CONFIG_CMDLINE. 1664 1665 Systems with fully functional boot loaders (i.e. non-embedded) 1666 should leave this option set to 'N'. 1667 1668config CMDLINE 1669 string "Built-in kernel command string" 1670 depends on CMDLINE_BOOL 1671 default "" 1672 ---help--- 1673 Enter arguments here that should be compiled into the kernel 1674 image and used at boot time. If the boot loader provides a 1675 command line at boot time, it is appended to this string to 1676 form the full kernel command line, when the system boots. 1677 1678 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 1679 change this behavior. 1680 1681 In most cases, the command line (whether built-in or provided 1682 by the boot loader) should specify the device for the root 1683 file system. 1684 1685config CMDLINE_OVERRIDE 1686 bool "Built-in command line overrides boot loader arguments" 1687 depends on CMDLINE_BOOL 1688 ---help--- 1689 Set this option to 'Y' to have the kernel ignore the boot loader 1690 command line, and use ONLY the built-in command line. 1691 1692 This is used to work around broken boot loaders. This should 1693 be set to 'N' under normal conditions. 1694 1695endmenu 1696 1697config ARCH_ENABLE_MEMORY_HOTPLUG 1698 def_bool y 1699 depends on X86_64 || (X86_32 && HIGHMEM) 1700 1701config ARCH_ENABLE_MEMORY_HOTREMOVE 1702 def_bool y 1703 depends on MEMORY_HOTPLUG 1704 1705config HAVE_ARCH_EARLY_PFN_TO_NID 1706 def_bool X86_64 1707 depends on NUMA 1708 1709config USE_PERCPU_NUMA_NODE_ID 1710 def_bool X86_64 1711 depends on NUMA 1712 1713menu "Power management and ACPI options" 1714 1715config ARCH_HIBERNATION_HEADER 1716 def_bool y 1717 depends on X86_64 && HIBERNATION 1718 1719source "kernel/power/Kconfig" 1720 1721source "drivers/acpi/Kconfig" 1722 1723source "drivers/sfi/Kconfig" 1724 1725config X86_APM_BOOT 1726 def_bool y 1727 depends on APM || APM_MODULE 1728 1729menuconfig APM 1730 tristate "APM (Advanced Power Management) BIOS support" 1731 depends on X86_32 && PM_SLEEP 1732 ---help--- 1733 APM is a BIOS specification for saving power using several different 1734 techniques. This is mostly useful for battery powered laptops with 1735 APM compliant BIOSes. If you say Y here, the system time will be 1736 reset after a RESUME operation, the /proc/apm device will provide 1737 battery status information, and user-space programs will receive 1738 notification of APM "events" (e.g. battery status change). 1739 1740 If you select "Y" here, you can disable actual use of the APM 1741 BIOS by passing the "apm=off" option to the kernel at boot time. 1742 1743 Note that the APM support is almost completely disabled for 1744 machines with more than one CPU. 1745 1746 In order to use APM, you will need supporting software. For location 1747 and more information, read <file:Documentation/power/pm.txt> and the 1748 Battery Powered Linux mini-HOWTO, available from 1749 <http://www.tldp.org/docs.html#howto>. 1750 1751 This driver does not spin down disk drives (see the hdparm(8) 1752 manpage ("man 8 hdparm") for that), and it doesn't turn off 1753 VESA-compliant "green" monitors. 1754 1755 This driver does not support the TI 4000M TravelMate and the ACER 1756 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1757 desktop machines also don't have compliant BIOSes, and this driver 1758 may cause those machines to panic during the boot phase. 1759 1760 Generally, if you don't have a battery in your machine, there isn't 1761 much point in using this driver and you should say N. If you get 1762 random kernel OOPSes or reboots that don't seem to be related to 1763 anything, try disabling/enabling this option (or disabling/enabling 1764 APM in your BIOS). 1765 1766 Some other things you should try when experiencing seemingly random, 1767 "weird" problems: 1768 1769 1) make sure that you have enough swap space and that it is 1770 enabled. 1771 2) pass the "no-hlt" option to the kernel 1772 3) switch on floating point emulation in the kernel and pass 1773 the "no387" option to the kernel 1774 4) pass the "floppy=nodma" option to the kernel 1775 5) pass the "mem=4M" option to the kernel (thereby disabling 1776 all but the first 4 MB of RAM) 1777 6) make sure that the CPU is not over clocked. 1778 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1779 8) disable the cache from your BIOS settings 1780 9) install a fan for the video card or exchange video RAM 1781 10) install a better fan for the CPU 1782 11) exchange RAM chips 1783 12) exchange the motherboard. 1784 1785 To compile this driver as a module, choose M here: the 1786 module will be called apm. 1787 1788if APM 1789 1790config APM_IGNORE_USER_SUSPEND 1791 bool "Ignore USER SUSPEND" 1792 ---help--- 1793 This option will ignore USER SUSPEND requests. On machines with a 1794 compliant APM BIOS, you want to say N. However, on the NEC Versa M 1795 series notebooks, it is necessary to say Y because of a BIOS bug. 1796 1797config APM_DO_ENABLE 1798 bool "Enable PM at boot time" 1799 ---help--- 1800 Enable APM features at boot time. From page 36 of the APM BIOS 1801 specification: "When disabled, the APM BIOS does not automatically 1802 power manage devices, enter the Standby State, enter the Suspend 1803 State, or take power saving steps in response to CPU Idle calls." 1804 This driver will make CPU Idle calls when Linux is idle (unless this 1805 feature is turned off -- see "Do CPU IDLE calls", below). This 1806 should always save battery power, but more complicated APM features 1807 will be dependent on your BIOS implementation. You may need to turn 1808 this option off if your computer hangs at boot time when using APM 1809 support, or if it beeps continuously instead of suspending. Turn 1810 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1811 T400CDT. This is off by default since most machines do fine without 1812 this feature. 1813 1814config APM_CPU_IDLE 1815 bool "Make CPU Idle calls when idle" 1816 ---help--- 1817 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 1818 On some machines, this can activate improved power savings, such as 1819 a slowed CPU clock rate, when the machine is idle. These idle calls 1820 are made after the idle loop has run for some length of time (e.g., 1821 333 mS). On some machines, this will cause a hang at boot time or 1822 whenever the CPU becomes idle. (On machines with more than one CPU, 1823 this option does nothing.) 1824 1825config APM_DISPLAY_BLANK 1826 bool "Enable console blanking using APM" 1827 ---help--- 1828 Enable console blanking using the APM. Some laptops can use this to 1829 turn off the LCD backlight when the screen blanker of the Linux 1830 virtual console blanks the screen. Note that this is only used by 1831 the virtual console screen blanker, and won't turn off the backlight 1832 when using the X Window system. This also doesn't have anything to 1833 do with your VESA-compliant power-saving monitor. Further, this 1834 option doesn't work for all laptops -- it might not turn off your 1835 backlight at all, or it might print a lot of errors to the console, 1836 especially if you are using gpm. 1837 1838config APM_ALLOW_INTS 1839 bool "Allow interrupts during APM BIOS calls" 1840 ---help--- 1841 Normally we disable external interrupts while we are making calls to 1842 the APM BIOS as a measure to lessen the effects of a badly behaving 1843 BIOS implementation. The BIOS should reenable interrupts if it 1844 needs to. Unfortunately, some BIOSes do not -- especially those in 1845 many of the newer IBM Thinkpads. If you experience hangs when you 1846 suspend, try setting this to Y. Otherwise, say N. 1847 1848endif # APM 1849 1850source "arch/x86/kernel/cpu/cpufreq/Kconfig" 1851 1852source "drivers/cpuidle/Kconfig" 1853 1854source "drivers/idle/Kconfig" 1855 1856endmenu 1857 1858 1859menu "Bus options (PCI etc.)" 1860 1861config PCI 1862 bool "PCI support" 1863 default y 1864 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC) 1865 ---help--- 1866 Find out whether you have a PCI motherboard. PCI is the name of a 1867 bus system, i.e. the way the CPU talks to the other stuff inside 1868 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 1869 VESA. If you have PCI, say Y, otherwise N. 1870 1871choice 1872 prompt "PCI access mode" 1873 depends on X86_32 && PCI 1874 default PCI_GOANY 1875 ---help--- 1876 On PCI systems, the BIOS can be used to detect the PCI devices and 1877 determine their configuration. However, some old PCI motherboards 1878 have BIOS bugs and may crash if this is done. Also, some embedded 1879 PCI-based systems don't have any BIOS at all. Linux can also try to 1880 detect the PCI hardware directly without using the BIOS. 1881 1882 With this option, you can specify how Linux should detect the 1883 PCI devices. If you choose "BIOS", the BIOS will be used, 1884 if you choose "Direct", the BIOS won't be used, and if you 1885 choose "MMConfig", then PCI Express MMCONFIG will be used. 1886 If you choose "Any", the kernel will try MMCONFIG, then the 1887 direct access method and falls back to the BIOS if that doesn't 1888 work. If unsure, go with the default, which is "Any". 1889 1890config PCI_GOBIOS 1891 bool "BIOS" 1892 1893config PCI_GOMMCONFIG 1894 bool "MMConfig" 1895 1896config PCI_GODIRECT 1897 bool "Direct" 1898 1899config PCI_GOOLPC 1900 bool "OLPC" 1901 depends on OLPC 1902 1903config PCI_GOANY 1904 bool "Any" 1905 1906endchoice 1907 1908config PCI_BIOS 1909 def_bool y 1910 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 1911 1912# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 1913config PCI_DIRECT 1914 def_bool y 1915 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC)) 1916 1917config PCI_MMCONFIG 1918 def_bool y 1919 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 1920 1921config PCI_OLPC 1922 def_bool y 1923 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 1924 1925config PCI_DOMAINS 1926 def_bool y 1927 depends on PCI 1928 1929config PCI_MMCONFIG 1930 bool "Support mmconfig PCI config space access" 1931 depends on X86_64 && PCI && ACPI 1932 1933config PCI_CNB20LE_QUIRK 1934 bool "Read CNB20LE Host Bridge Windows" 1935 depends on PCI 1936 help 1937 Read the PCI windows out of the CNB20LE host bridge. This allows 1938 PCI hotplug to work on systems with the CNB20LE chipset which do 1939 not have ACPI. 1940 1941config DMAR 1942 bool "Support for DMA Remapping Devices (EXPERIMENTAL)" 1943 depends on PCI_MSI && ACPI && EXPERIMENTAL 1944 help 1945 DMA remapping (DMAR) devices support enables independent address 1946 translations for Direct Memory Access (DMA) from devices. 1947 These DMA remapping devices are reported via ACPI tables 1948 and include PCI device scope covered by these DMA 1949 remapping devices. 1950 1951config DMAR_DEFAULT_ON 1952 def_bool y 1953 prompt "Enable DMA Remapping Devices by default" 1954 depends on DMAR 1955 help 1956 Selecting this option will enable a DMAR device at boot time if 1957 one is found. If this option is not selected, DMAR support can 1958 be enabled by passing intel_iommu=on to the kernel. It is 1959 recommended you say N here while the DMAR code remains 1960 experimental. 1961 1962config DMAR_BROKEN_GFX_WA 1963 bool "Workaround broken graphics drivers (going away soon)" 1964 depends on DMAR && BROKEN 1965 ---help--- 1966 Current Graphics drivers tend to use physical address 1967 for DMA and avoid using DMA APIs. Setting this config 1968 option permits the IOMMU driver to set a unity map for 1969 all the OS-visible memory. Hence the driver can continue 1970 to use physical addresses for DMA, at least until this 1971 option is removed in the 2.6.32 kernel. 1972 1973config DMAR_FLOPPY_WA 1974 def_bool y 1975 depends on DMAR 1976 ---help--- 1977 Floppy disk drivers are known to bypass DMA API calls 1978 thereby failing to work when IOMMU is enabled. This 1979 workaround will setup a 1:1 mapping for the first 1980 16MiB to make floppy (an ISA device) work. 1981 1982config INTR_REMAP 1983 bool "Support for Interrupt Remapping (EXPERIMENTAL)" 1984 depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL 1985 ---help--- 1986 Supports Interrupt remapping for IO-APIC and MSI devices. 1987 To use x2apic mode in the CPU's which support x2APIC enhancements or 1988 to support platforms with CPU's having > 8 bit APIC ID, say Y. 1989 1990source "drivers/pci/pcie/Kconfig" 1991 1992source "drivers/pci/Kconfig" 1993 1994# x86_64 have no ISA slots, but do have ISA-style DMA. 1995config ISA_DMA_API 1996 def_bool y 1997 1998if X86_32 1999 2000config ISA 2001 bool "ISA support" 2002 ---help--- 2003 Find out whether you have ISA slots on your motherboard. ISA is the 2004 name of a bus system, i.e. the way the CPU talks to the other stuff 2005 inside your box. Other bus systems are PCI, EISA, MicroChannel 2006 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2007 newer boards don't support it. If you have ISA, say Y, otherwise N. 2008 2009config EISA 2010 bool "EISA support" 2011 depends on ISA 2012 ---help--- 2013 The Extended Industry Standard Architecture (EISA) bus was 2014 developed as an open alternative to the IBM MicroChannel bus. 2015 2016 The EISA bus provided some of the features of the IBM MicroChannel 2017 bus while maintaining backward compatibility with cards made for 2018 the older ISA bus. The EISA bus saw limited use between 1988 and 2019 1995 when it was made obsolete by the PCI bus. 2020 2021 Say Y here if you are building a kernel for an EISA-based machine. 2022 2023 Otherwise, say N. 2024 2025source "drivers/eisa/Kconfig" 2026 2027config MCA 2028 bool "MCA support" 2029 ---help--- 2030 MicroChannel Architecture is found in some IBM PS/2 machines and 2031 laptops. It is a bus system similar to PCI or ISA. See 2032 <file:Documentation/mca.txt> (and especially the web page given 2033 there) before attempting to build an MCA bus kernel. 2034 2035source "drivers/mca/Kconfig" 2036 2037config SCx200 2038 tristate "NatSemi SCx200 support" 2039 ---help--- 2040 This provides basic support for National Semiconductor's 2041 (now AMD's) Geode processors. The driver probes for the 2042 PCI-IDs of several on-chip devices, so its a good dependency 2043 for other scx200_* drivers. 2044 2045 If compiled as a module, the driver is named scx200. 2046 2047config SCx200HR_TIMER 2048 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2049 depends on SCx200 && GENERIC_TIME 2050 default y 2051 ---help--- 2052 This driver provides a clocksource built upon the on-chip 2053 27MHz high-resolution timer. Its also a workaround for 2054 NSC Geode SC-1100's buggy TSC, which loses time when the 2055 processor goes idle (as is done by the scheduler). The 2056 other workaround is idle=poll boot option. 2057 2058config OLPC 2059 bool "One Laptop Per Child support" 2060 select GPIOLIB 2061 ---help--- 2062 Add support for detecting the unique features of the OLPC 2063 XO hardware. 2064 2065endif # X86_32 2066 2067config K8_NB 2068 def_bool y 2069 depends on CPU_SUP_AMD && PCI 2070 2071source "drivers/pcmcia/Kconfig" 2072 2073source "drivers/pci/hotplug/Kconfig" 2074 2075endmenu 2076 2077 2078menu "Executable file formats / Emulations" 2079 2080source "fs/Kconfig.binfmt" 2081 2082config IA32_EMULATION 2083 bool "IA32 Emulation" 2084 depends on X86_64 2085 select COMPAT_BINFMT_ELF 2086 ---help--- 2087 Include code to run 32-bit programs under a 64-bit kernel. You should 2088 likely turn this on, unless you're 100% sure that you don't have any 2089 32-bit programs left. 2090 2091config IA32_AOUT 2092 tristate "IA32 a.out support" 2093 depends on IA32_EMULATION 2094 ---help--- 2095 Support old a.out binaries in the 32bit emulation. 2096 2097config COMPAT 2098 def_bool y 2099 depends on IA32_EMULATION 2100 2101config COMPAT_FOR_U64_ALIGNMENT 2102 def_bool COMPAT 2103 depends on X86_64 2104 2105config SYSVIPC_COMPAT 2106 def_bool y 2107 depends on COMPAT && SYSVIPC 2108 2109endmenu 2110 2111 2112config HAVE_ATOMIC_IOMAP 2113 def_bool y 2114 depends on X86_32 2115 2116source "net/Kconfig" 2117 2118source "drivers/Kconfig" 2119 2120source "drivers/firmware/Kconfig" 2121 2122source "fs/Kconfig" 2123 2124source "arch/x86/Kconfig.debug" 2125 2126source "security/Kconfig" 2127 2128source "crypto/Kconfig" 2129 2130source "arch/x86/kvm/Kconfig" 2131 2132source "lib/Kconfig" 2133