1# Select 32 or 64 bit 2config 64BIT 3 bool "64-bit kernel" if ARCH = "x86" 4 default ARCH = "x86_64" 5 ---help--- 6 Say yes to build a 64-bit kernel - formerly known as x86_64 7 Say no to build a 32-bit kernel - formerly known as i386 8 9config X86_32 10 def_bool !64BIT 11 12config X86_64 13 def_bool 64BIT 14 15### Arch settings 16config X86 17 def_bool y 18 select HAVE_AOUT if X86_32 19 select HAVE_READQ 20 select HAVE_WRITEQ 21 select HAVE_UNSTABLE_SCHED_CLOCK 22 select HAVE_IDE 23 select HAVE_OPROFILE 24 select HAVE_PERF_EVENTS if (!M386 && !M486) 25 select HAVE_IOREMAP_PROT 26 select HAVE_KPROBES 27 select ARCH_WANT_OPTIONAL_GPIOLIB 28 select ARCH_WANT_FRAME_POINTERS 29 select HAVE_DMA_ATTRS 30 select HAVE_KRETPROBES 31 select HAVE_OPTPROBES 32 select HAVE_FTRACE_MCOUNT_RECORD 33 select HAVE_DYNAMIC_FTRACE 34 select HAVE_FUNCTION_TRACER 35 select HAVE_FUNCTION_GRAPH_TRACER 36 select HAVE_FUNCTION_GRAPH_FP_TEST 37 select HAVE_FUNCTION_TRACE_MCOUNT_TEST 38 select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE 39 select HAVE_SYSCALL_TRACEPOINTS 40 select HAVE_KVM 41 select HAVE_ARCH_KGDB 42 select HAVE_ARCH_TRACEHOOK 43 select HAVE_GENERIC_DMA_COHERENT if X86_32 44 select HAVE_EFFICIENT_UNALIGNED_ACCESS 45 select USER_STACKTRACE_SUPPORT 46 select HAVE_REGS_AND_STACK_ACCESS_API 47 select HAVE_DMA_API_DEBUG 48 select HAVE_KERNEL_GZIP 49 select HAVE_KERNEL_BZIP2 50 select HAVE_KERNEL_LZMA 51 select HAVE_KERNEL_LZO 52 select HAVE_HW_BREAKPOINT 53 select HAVE_MIXED_BREAKPOINTS_REGS 54 select PERF_EVENTS 55 select ANON_INODES 56 select HAVE_ARCH_KMEMCHECK 57 select HAVE_USER_RETURN_NOTIFIER 58 59config INSTRUCTION_DECODER 60 def_bool (KPROBES || PERF_EVENTS) 61 62config OUTPUT_FORMAT 63 string 64 default "elf32-i386" if X86_32 65 default "elf64-x86-64" if X86_64 66 67config ARCH_DEFCONFIG 68 string 69 default "arch/x86/configs/i386_defconfig" if X86_32 70 default "arch/x86/configs/x86_64_defconfig" if X86_64 71 72config GENERIC_TIME 73 def_bool y 74 75config GENERIC_CMOS_UPDATE 76 def_bool y 77 78config CLOCKSOURCE_WATCHDOG 79 def_bool y 80 81config GENERIC_CLOCKEVENTS 82 def_bool y 83 84config GENERIC_CLOCKEVENTS_BROADCAST 85 def_bool y 86 depends on X86_64 || (X86_32 && X86_LOCAL_APIC) 87 88config LOCKDEP_SUPPORT 89 def_bool y 90 91config STACKTRACE_SUPPORT 92 def_bool y 93 94config HAVE_LATENCYTOP_SUPPORT 95 def_bool y 96 97config MMU 98 def_bool y 99 100config ZONE_DMA 101 def_bool y 102 103config SBUS 104 bool 105 106config NEED_DMA_MAP_STATE 107 def_bool (X86_64 || DMAR || DMA_API_DEBUG) 108 109config NEED_SG_DMA_LENGTH 110 def_bool y 111 112config GENERIC_ISA_DMA 113 def_bool y 114 115config GENERIC_IOMAP 116 def_bool y 117 118config GENERIC_BUG 119 def_bool y 120 depends on BUG 121 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 122 123config GENERIC_BUG_RELATIVE_POINTERS 124 bool 125 126config GENERIC_HWEIGHT 127 def_bool y 128 129config GENERIC_GPIO 130 bool 131 132config ARCH_MAY_HAVE_PC_FDC 133 def_bool y 134 135config RWSEM_GENERIC_SPINLOCK 136 def_bool !X86_XADD 137 138config RWSEM_XCHGADD_ALGORITHM 139 def_bool X86_XADD 140 141config ARCH_HAS_CPU_IDLE_WAIT 142 def_bool y 143 144config GENERIC_CALIBRATE_DELAY 145 def_bool y 146 147config GENERIC_TIME_VSYSCALL 148 bool 149 default X86_64 150 151config ARCH_HAS_CPU_RELAX 152 def_bool y 153 154config ARCH_HAS_DEFAULT_IDLE 155 def_bool y 156 157config ARCH_HAS_CACHE_LINE_SIZE 158 def_bool y 159 160config HAVE_SETUP_PER_CPU_AREA 161 def_bool y 162 163config NEED_PER_CPU_EMBED_FIRST_CHUNK 164 def_bool y 165 166config NEED_PER_CPU_PAGE_FIRST_CHUNK 167 def_bool y 168 169config HAVE_CPUMASK_OF_CPU_MAP 170 def_bool X86_64_SMP 171 172config ARCH_HIBERNATION_POSSIBLE 173 def_bool y 174 175config ARCH_SUSPEND_POSSIBLE 176 def_bool y 177 178config ZONE_DMA32 179 bool 180 default X86_64 181 182config ARCH_POPULATES_NODE_MAP 183 def_bool y 184 185config AUDIT_ARCH 186 bool 187 default X86_64 188 189config ARCH_SUPPORTS_OPTIMIZED_INLINING 190 def_bool y 191 192config ARCH_SUPPORTS_DEBUG_PAGEALLOC 193 def_bool y 194 195config HAVE_EARLY_RES 196 def_bool y 197 198config HAVE_INTEL_TXT 199 def_bool y 200 depends on EXPERIMENTAL && DMAR && ACPI 201 202# Use the generic interrupt handling code in kernel/irq/: 203config GENERIC_HARDIRQS 204 def_bool y 205 206config GENERIC_HARDIRQS_NO__DO_IRQ 207 def_bool y 208 209config GENERIC_IRQ_PROBE 210 def_bool y 211 212config GENERIC_PENDING_IRQ 213 def_bool y 214 depends on GENERIC_HARDIRQS && SMP 215 216config USE_GENERIC_SMP_HELPERS 217 def_bool y 218 depends on SMP 219 220config X86_32_SMP 221 def_bool y 222 depends on X86_32 && SMP 223 224config X86_64_SMP 225 def_bool y 226 depends on X86_64 && SMP 227 228config X86_HT 229 def_bool y 230 depends on SMP 231 232config X86_TRAMPOLINE 233 def_bool y 234 depends on SMP || (64BIT && ACPI_SLEEP) 235 236config X86_32_LAZY_GS 237 def_bool y 238 depends on X86_32 && !CC_STACKPROTECTOR 239 240config ARCH_HWEIGHT_CFLAGS 241 string 242 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32 243 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_64 244 245config KTIME_SCALAR 246 def_bool X86_32 247source "init/Kconfig" 248source "kernel/Kconfig.freezer" 249 250menu "Processor type and features" 251 252source "kernel/time/Kconfig" 253 254config SMP 255 bool "Symmetric multi-processing support" 256 ---help--- 257 This enables support for systems with more than one CPU. If you have 258 a system with only one CPU, like most personal computers, say N. If 259 you have a system with more than one CPU, say Y. 260 261 If you say N here, the kernel will run on single and multiprocessor 262 machines, but will use only one CPU of a multiprocessor machine. If 263 you say Y here, the kernel will run on many, but not all, 264 singleprocessor machines. On a singleprocessor machine, the kernel 265 will run faster if you say N here. 266 267 Note that if you say Y here and choose architecture "586" or 268 "Pentium" under "Processor family", the kernel will not work on 486 269 architectures. Similarly, multiprocessor kernels for the "PPro" 270 architecture may not work on all Pentium based boards. 271 272 People using multiprocessor machines who say Y here should also say 273 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 274 Management" code will be disabled if you say Y here. 275 276 See also <file:Documentation/i386/IO-APIC.txt>, 277 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 278 <http://www.tldp.org/docs.html#howto>. 279 280 If you don't know what to do here, say N. 281 282config X86_X2APIC 283 bool "Support x2apic" 284 depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP 285 ---help--- 286 This enables x2apic support on CPUs that have this feature. 287 288 This allows 32-bit apic IDs (so it can support very large systems), 289 and accesses the local apic via MSRs not via mmio. 290 291 If you don't know what to do here, say N. 292 293config SPARSE_IRQ 294 bool "Support sparse irq numbering" 295 depends on PCI_MSI || HT_IRQ 296 ---help--- 297 This enables support for sparse irqs. This is useful for distro 298 kernels that want to define a high CONFIG_NR_CPUS value but still 299 want to have low kernel memory footprint on smaller machines. 300 301 ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread 302 out the irq_desc[] array in a more NUMA-friendly way. ) 303 304 If you don't know what to do here, say N. 305 306config NUMA_IRQ_DESC 307 def_bool y 308 depends on SPARSE_IRQ && NUMA 309 310config X86_MPPARSE 311 bool "Enable MPS table" if ACPI 312 default y 313 depends on X86_LOCAL_APIC 314 ---help--- 315 For old smp systems that do not have proper acpi support. Newer systems 316 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 317 318config X86_BIGSMP 319 bool "Support for big SMP systems with more than 8 CPUs" 320 depends on X86_32 && SMP 321 ---help--- 322 This option is needed for the systems that have more than 8 CPUs 323 324if X86_32 325config X86_EXTENDED_PLATFORM 326 bool "Support for extended (non-PC) x86 platforms" 327 default y 328 ---help--- 329 If you disable this option then the kernel will only support 330 standard PC platforms. (which covers the vast majority of 331 systems out there.) 332 333 If you enable this option then you'll be able to select support 334 for the following (non-PC) 32 bit x86 platforms: 335 AMD Elan 336 NUMAQ (IBM/Sequent) 337 RDC R-321x SoC 338 SGI 320/540 (Visual Workstation) 339 Summit/EXA (IBM x440) 340 Unisys ES7000 IA32 series 341 Moorestown MID devices 342 343 If you have one of these systems, or if you want to build a 344 generic distribution kernel, say Y here - otherwise say N. 345endif 346 347if X86_64 348config X86_EXTENDED_PLATFORM 349 bool "Support for extended (non-PC) x86 platforms" 350 default y 351 ---help--- 352 If you disable this option then the kernel will only support 353 standard PC platforms. (which covers the vast majority of 354 systems out there.) 355 356 If you enable this option then you'll be able to select support 357 for the following (non-PC) 64 bit x86 platforms: 358 ScaleMP vSMP 359 SGI Ultraviolet 360 361 If you have one of these systems, or if you want to build a 362 generic distribution kernel, say Y here - otherwise say N. 363endif 364# This is an alphabetically sorted list of 64 bit extended platforms 365# Please maintain the alphabetic order if and when there are additions 366 367config X86_VSMP 368 bool "ScaleMP vSMP" 369 select PARAVIRT 370 depends on X86_64 && PCI 371 depends on X86_EXTENDED_PLATFORM 372 ---help--- 373 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 374 supposed to run on these EM64T-based machines. Only choose this option 375 if you have one of these machines. 376 377config X86_UV 378 bool "SGI Ultraviolet" 379 depends on X86_64 380 depends on X86_EXTENDED_PLATFORM 381 depends on NUMA 382 depends on X86_X2APIC 383 ---help--- 384 This option is needed in order to support SGI Ultraviolet systems. 385 If you don't have one of these, you should say N here. 386 387# Following is an alphabetically sorted list of 32 bit extended platforms 388# Please maintain the alphabetic order if and when there are additions 389 390config X86_ELAN 391 bool "AMD Elan" 392 depends on X86_32 393 depends on X86_EXTENDED_PLATFORM 394 ---help--- 395 Select this for an AMD Elan processor. 396 397 Do not use this option for K6/Athlon/Opteron processors! 398 399 If unsure, choose "PC-compatible" instead. 400 401config X86_MRST 402 bool "Moorestown MID platform" 403 depends on PCI 404 depends on PCI_GOANY 405 depends on X86_32 406 depends on X86_EXTENDED_PLATFORM 407 depends on X86_IO_APIC 408 select APB_TIMER 409 ---help--- 410 Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin 411 Internet Device(MID) platform. Moorestown consists of two chips: 412 Lincroft (CPU core, graphics, and memory controller) and Langwell IOH. 413 Unlike standard x86 PCs, Moorestown does not have many legacy devices 414 nor standard legacy replacement devices/features. e.g. Moorestown does 415 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports. 416 417config X86_RDC321X 418 bool "RDC R-321x SoC" 419 depends on X86_32 420 depends on X86_EXTENDED_PLATFORM 421 select M486 422 select X86_REBOOTFIXUPS 423 ---help--- 424 This option is needed for RDC R-321x system-on-chip, also known 425 as R-8610-(G). 426 If you don't have one of these chips, you should say N here. 427 428config X86_32_NON_STANDARD 429 bool "Support non-standard 32-bit SMP architectures" 430 depends on X86_32 && SMP 431 depends on X86_EXTENDED_PLATFORM 432 ---help--- 433 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default 434 subarchitectures. It is intended for a generic binary kernel. 435 if you select them all, kernel will probe it one by one. and will 436 fallback to default. 437 438# Alphabetically sorted list of Non standard 32 bit platforms 439 440config X86_NUMAQ 441 bool "NUMAQ (IBM/Sequent)" 442 depends on X86_32_NON_STANDARD 443 depends on PCI 444 select NUMA 445 select X86_MPPARSE 446 ---help--- 447 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent) 448 NUMA multiquad box. This changes the way that processors are 449 bootstrapped, and uses Clustered Logical APIC addressing mode instead 450 of Flat Logical. You will need a new lynxer.elf file to flash your 451 firmware with - send email to <Martin.Bligh@us.ibm.com>. 452 453config X86_SUPPORTS_MEMORY_FAILURE 454 def_bool y 455 # MCE code calls memory_failure(): 456 depends on X86_MCE 457 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 458 depends on !X86_NUMAQ 459 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 460 depends on X86_64 || !SPARSEMEM 461 select ARCH_SUPPORTS_MEMORY_FAILURE 462 463config X86_VISWS 464 bool "SGI 320/540 (Visual Workstation)" 465 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT 466 depends on X86_32_NON_STANDARD 467 ---help--- 468 The SGI Visual Workstation series is an IA32-based workstation 469 based on SGI systems chips with some legacy PC hardware attached. 470 471 Say Y here to create a kernel to run on the SGI 320 or 540. 472 473 A kernel compiled for the Visual Workstation will run on general 474 PCs as well. See <file:Documentation/sgi-visws.txt> for details. 475 476config X86_SUMMIT 477 bool "Summit/EXA (IBM x440)" 478 depends on X86_32_NON_STANDARD 479 ---help--- 480 This option is needed for IBM systems that use the Summit/EXA chipset. 481 In particular, it is needed for the x440. 482 483config X86_ES7000 484 bool "Unisys ES7000 IA32 series" 485 depends on X86_32_NON_STANDARD && X86_BIGSMP 486 ---help--- 487 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is 488 supposed to run on an IA32-based Unisys ES7000 system. 489 490config SCHED_OMIT_FRAME_POINTER 491 def_bool y 492 prompt "Single-depth WCHAN output" 493 depends on X86 494 ---help--- 495 Calculate simpler /proc/<PID>/wchan values. If this option 496 is disabled then wchan values will recurse back to the 497 caller function. This provides more accurate wchan values, 498 at the expense of slightly more scheduling overhead. 499 500 If in doubt, say "Y". 501 502menuconfig PARAVIRT_GUEST 503 bool "Paravirtualized guest support" 504 ---help--- 505 Say Y here to get to see options related to running Linux under 506 various hypervisors. This option alone does not add any kernel code. 507 508 If you say N, all options in this submenu will be skipped and disabled. 509 510if PARAVIRT_GUEST 511 512source "arch/x86/xen/Kconfig" 513 514config VMI 515 bool "VMI Guest support (DEPRECATED)" 516 select PARAVIRT 517 depends on X86_32 518 ---help--- 519 VMI provides a paravirtualized interface to the VMware ESX server 520 (it could be used by other hypervisors in theory too, but is not 521 at the moment), by linking the kernel to a GPL-ed ROM module 522 provided by the hypervisor. 523 524 As of September 2009, VMware has started a phased retirement 525 of this feature from VMware's products. Please see 526 feature-removal-schedule.txt for details. If you are 527 planning to enable this option, please note that you cannot 528 live migrate a VMI enabled VM to a future VMware product, 529 which doesn't support VMI. So if you expect your kernel to 530 seamlessly migrate to newer VMware products, keep this 531 disabled. 532 533config KVM_CLOCK 534 bool "KVM paravirtualized clock" 535 select PARAVIRT 536 select PARAVIRT_CLOCK 537 ---help--- 538 Turning on this option will allow you to run a paravirtualized clock 539 when running over the KVM hypervisor. Instead of relying on a PIT 540 (or probably other) emulation by the underlying device model, the host 541 provides the guest with timing infrastructure such as time of day, and 542 system time 543 544config KVM_GUEST 545 bool "KVM Guest support" 546 select PARAVIRT 547 ---help--- 548 This option enables various optimizations for running under the KVM 549 hypervisor. 550 551source "arch/x86/lguest/Kconfig" 552 553config PARAVIRT 554 bool "Enable paravirtualization code" 555 ---help--- 556 This changes the kernel so it can modify itself when it is run 557 under a hypervisor, potentially improving performance significantly 558 over full virtualization. However, when run without a hypervisor 559 the kernel is theoretically slower and slightly larger. 560 561config PARAVIRT_SPINLOCKS 562 bool "Paravirtualization layer for spinlocks" 563 depends on PARAVIRT && SMP && EXPERIMENTAL 564 ---help--- 565 Paravirtualized spinlocks allow a pvops backend to replace the 566 spinlock implementation with something virtualization-friendly 567 (for example, block the virtual CPU rather than spinning). 568 569 Unfortunately the downside is an up to 5% performance hit on 570 native kernels, with various workloads. 571 572 If you are unsure how to answer this question, answer N. 573 574config PARAVIRT_CLOCK 575 bool 576 577endif 578 579config PARAVIRT_DEBUG 580 bool "paravirt-ops debugging" 581 depends on PARAVIRT && DEBUG_KERNEL 582 ---help--- 583 Enable to debug paravirt_ops internals. Specifically, BUG if 584 a paravirt_op is missing when it is called. 585 586config NO_BOOTMEM 587 default y 588 bool "Disable Bootmem code" 589 ---help--- 590 Use early_res directly instead of bootmem before slab is ready. 591 - allocator (buddy) [generic] 592 - early allocator (bootmem) [generic] 593 - very early allocator (reserve_early*()) [x86] 594 - very very early allocator (early brk model) [x86] 595 So reduce one layer between early allocator to final allocator 596 597 598config MEMTEST 599 bool "Memtest" 600 ---help--- 601 This option adds a kernel parameter 'memtest', which allows memtest 602 to be set. 603 memtest=0, mean disabled; -- default 604 memtest=1, mean do 1 test pattern; 605 ... 606 memtest=4, mean do 4 test patterns. 607 If you are unsure how to answer this question, answer N. 608 609config X86_SUMMIT_NUMA 610 def_bool y 611 depends on X86_32 && NUMA && X86_32_NON_STANDARD 612 613config X86_CYCLONE_TIMER 614 def_bool y 615 depends on X86_32_NON_STANDARD 616 617source "arch/x86/Kconfig.cpu" 618 619config HPET_TIMER 620 def_bool X86_64 621 prompt "HPET Timer Support" if X86_32 622 ---help--- 623 Use the IA-PC HPET (High Precision Event Timer) to manage 624 time in preference to the PIT and RTC, if a HPET is 625 present. 626 HPET is the next generation timer replacing legacy 8254s. 627 The HPET provides a stable time base on SMP 628 systems, unlike the TSC, but it is more expensive to access, 629 as it is off-chip. You can find the HPET spec at 630 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>. 631 632 You can safely choose Y here. However, HPET will only be 633 activated if the platform and the BIOS support this feature. 634 Otherwise the 8254 will be used for timing services. 635 636 Choose N to continue using the legacy 8254 timer. 637 638config HPET_EMULATE_RTC 639 def_bool y 640 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 641 642config APB_TIMER 643 def_bool y if MRST 644 prompt "Langwell APB Timer Support" if X86_MRST 645 help 646 APB timer is the replacement for 8254, HPET on X86 MID platforms. 647 The APBT provides a stable time base on SMP 648 systems, unlike the TSC, but it is more expensive to access, 649 as it is off-chip. APB timers are always running regardless of CPU 650 C states, they are used as per CPU clockevent device when possible. 651 652# Mark as embedded because too many people got it wrong. 653# The code disables itself when not needed. 654config DMI 655 default y 656 bool "Enable DMI scanning" if EMBEDDED 657 ---help--- 658 Enabled scanning of DMI to identify machine quirks. Say Y 659 here unless you have verified that your setup is not 660 affected by entries in the DMI blacklist. Required by PNP 661 BIOS code. 662 663config GART_IOMMU 664 bool "GART IOMMU support" if EMBEDDED 665 default y 666 select SWIOTLB 667 depends on X86_64 && PCI && K8_NB 668 ---help--- 669 Support for full DMA access of devices with 32bit memory access only 670 on systems with more than 3GB. This is usually needed for USB, 671 sound, many IDE/SATA chipsets and some other devices. 672 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART 673 based hardware IOMMU and a software bounce buffer based IOMMU used 674 on Intel systems and as fallback. 675 The code is only active when needed (enough memory and limited 676 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified 677 too. 678 679config CALGARY_IOMMU 680 bool "IBM Calgary IOMMU support" 681 select SWIOTLB 682 depends on X86_64 && PCI && EXPERIMENTAL 683 ---help--- 684 Support for hardware IOMMUs in IBM's xSeries x366 and x460 685 systems. Needed to run systems with more than 3GB of memory 686 properly with 32-bit PCI devices that do not support DAC 687 (Double Address Cycle). Calgary also supports bus level 688 isolation, where all DMAs pass through the IOMMU. This 689 prevents them from going anywhere except their intended 690 destination. This catches hard-to-find kernel bugs and 691 mis-behaving drivers and devices that do not use the DMA-API 692 properly to set up their DMA buffers. The IOMMU can be 693 turned off at boot time with the iommu=off parameter. 694 Normally the kernel will make the right choice by itself. 695 If unsure, say Y. 696 697config CALGARY_IOMMU_ENABLED_BY_DEFAULT 698 def_bool y 699 prompt "Should Calgary be enabled by default?" 700 depends on CALGARY_IOMMU 701 ---help--- 702 Should Calgary be enabled by default? if you choose 'y', Calgary 703 will be used (if it exists). If you choose 'n', Calgary will not be 704 used even if it exists. If you choose 'n' and would like to use 705 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 706 If unsure, say Y. 707 708config AMD_IOMMU 709 bool "AMD IOMMU support" 710 select SWIOTLB 711 select PCI_MSI 712 depends on X86_64 && PCI && ACPI 713 ---help--- 714 With this option you can enable support for AMD IOMMU hardware in 715 your system. An IOMMU is a hardware component which provides 716 remapping of DMA memory accesses from devices. With an AMD IOMMU you 717 can isolate the the DMA memory of different devices and protect the 718 system from misbehaving device drivers or hardware. 719 720 You can find out if your system has an AMD IOMMU if you look into 721 your BIOS for an option to enable it or if you have an IVRS ACPI 722 table. 723 724config AMD_IOMMU_STATS 725 bool "Export AMD IOMMU statistics to debugfs" 726 depends on AMD_IOMMU 727 select DEBUG_FS 728 ---help--- 729 This option enables code in the AMD IOMMU driver to collect various 730 statistics about whats happening in the driver and exports that 731 information to userspace via debugfs. 732 If unsure, say N. 733 734# need this always selected by IOMMU for the VIA workaround 735config SWIOTLB 736 def_bool y if X86_64 737 ---help--- 738 Support for software bounce buffers used on x86-64 systems 739 which don't have a hardware IOMMU (e.g. the current generation 740 of Intel's x86-64 CPUs). Using this PCI devices which can only 741 access 32-bits of memory can be used on systems with more than 742 3 GB of memory. If unsure, say Y. 743 744config IOMMU_HELPER 745 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU) 746 747config IOMMU_API 748 def_bool (AMD_IOMMU || DMAR) 749 750config MAXSMP 751 bool "Configure Maximum number of SMP Processors and NUMA Nodes" 752 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL 753 select CPUMASK_OFFSTACK 754 ---help--- 755 Configure maximum number of CPUS and NUMA Nodes for this architecture. 756 If unsure, say N. 757 758config NR_CPUS 759 int "Maximum number of CPUs" if SMP && !MAXSMP 760 range 2 8 if SMP && X86_32 && !X86_BIGSMP 761 range 2 512 if SMP && !MAXSMP 762 default "1" if !SMP 763 default "4096" if MAXSMP 764 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000) 765 default "8" if SMP 766 ---help--- 767 This allows you to specify the maximum number of CPUs which this 768 kernel will support. The maximum supported value is 512 and the 769 minimum value which makes sense is 2. 770 771 This is purely to save memory - each supported CPU adds 772 approximately eight kilobytes to the kernel image. 773 774config SCHED_SMT 775 bool "SMT (Hyperthreading) scheduler support" 776 depends on X86_HT 777 ---help--- 778 SMT scheduler support improves the CPU scheduler's decision making 779 when dealing with Intel Pentium 4 chips with HyperThreading at a 780 cost of slightly increased overhead in some places. If unsure say 781 N here. 782 783config SCHED_MC 784 def_bool y 785 prompt "Multi-core scheduler support" 786 depends on X86_HT 787 ---help--- 788 Multi-core scheduler support improves the CPU scheduler's decision 789 making when dealing with multi-core CPU chips at a cost of slightly 790 increased overhead in some places. If unsure say N here. 791 792source "kernel/Kconfig.preempt" 793 794config X86_UP_APIC 795 bool "Local APIC support on uniprocessors" 796 depends on X86_32 && !SMP && !X86_32_NON_STANDARD 797 ---help--- 798 A local APIC (Advanced Programmable Interrupt Controller) is an 799 integrated interrupt controller in the CPU. If you have a single-CPU 800 system which has a processor with a local APIC, you can say Y here to 801 enable and use it. If you say Y here even though your machine doesn't 802 have a local APIC, then the kernel will still run with no slowdown at 803 all. The local APIC supports CPU-generated self-interrupts (timer, 804 performance counters), and the NMI watchdog which detects hard 805 lockups. 806 807config X86_UP_IOAPIC 808 bool "IO-APIC support on uniprocessors" 809 depends on X86_UP_APIC 810 ---help--- 811 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 812 SMP-capable replacement for PC-style interrupt controllers. Most 813 SMP systems and many recent uniprocessor systems have one. 814 815 If you have a single-CPU system with an IO-APIC, you can say Y here 816 to use it. If you say Y here even though your machine doesn't have 817 an IO-APIC, then the kernel will still run with no slowdown at all. 818 819config X86_LOCAL_APIC 820 def_bool y 821 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC 822 823config X86_IO_APIC 824 def_bool y 825 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC 826 827config X86_VISWS_APIC 828 def_bool y 829 depends on X86_32 && X86_VISWS 830 831config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 832 bool "Reroute for broken boot IRQs" 833 depends on X86_IO_APIC 834 ---help--- 835 This option enables a workaround that fixes a source of 836 spurious interrupts. This is recommended when threaded 837 interrupt handling is used on systems where the generation of 838 superfluous "boot interrupts" cannot be disabled. 839 840 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 841 entry in the chipset's IO-APIC is masked (as, e.g. the RT 842 kernel does during interrupt handling). On chipsets where this 843 boot IRQ generation cannot be disabled, this workaround keeps 844 the original IRQ line masked so that only the equivalent "boot 845 IRQ" is delivered to the CPUs. The workaround also tells the 846 kernel to set up the IRQ handler on the boot IRQ line. In this 847 way only one interrupt is delivered to the kernel. Otherwise 848 the spurious second interrupt may cause the kernel to bring 849 down (vital) interrupt lines. 850 851 Only affects "broken" chipsets. Interrupt sharing may be 852 increased on these systems. 853 854config X86_MCE 855 bool "Machine Check / overheating reporting" 856 ---help--- 857 Machine Check support allows the processor to notify the 858 kernel if it detects a problem (e.g. overheating, data corruption). 859 The action the kernel takes depends on the severity of the problem, 860 ranging from warning messages to halting the machine. 861 862config X86_MCE_INTEL 863 def_bool y 864 prompt "Intel MCE features" 865 depends on X86_MCE && X86_LOCAL_APIC 866 ---help--- 867 Additional support for intel specific MCE features such as 868 the thermal monitor. 869 870config X86_MCE_AMD 871 def_bool y 872 prompt "AMD MCE features" 873 depends on X86_MCE && X86_LOCAL_APIC 874 ---help--- 875 Additional support for AMD specific MCE features such as 876 the DRAM Error Threshold. 877 878config X86_ANCIENT_MCE 879 bool "Support for old Pentium 5 / WinChip machine checks" 880 depends on X86_32 && X86_MCE 881 ---help--- 882 Include support for machine check handling on old Pentium 5 or WinChip 883 systems. These typically need to be enabled explicitely on the command 884 line. 885 886config X86_MCE_THRESHOLD 887 depends on X86_MCE_AMD || X86_MCE_INTEL 888 def_bool y 889 890config X86_MCE_INJECT 891 depends on X86_MCE 892 tristate "Machine check injector support" 893 ---help--- 894 Provide support for injecting machine checks for testing purposes. 895 If you don't know what a machine check is and you don't do kernel 896 QA it is safe to say n. 897 898config X86_THERMAL_VECTOR 899 def_bool y 900 depends on X86_MCE_INTEL 901 902config VM86 903 bool "Enable VM86 support" if EMBEDDED 904 default y 905 depends on X86_32 906 ---help--- 907 This option is required by programs like DOSEMU to run 16-bit legacy 908 code on X86 processors. It also may be needed by software like 909 XFree86 to initialize some video cards via BIOS. Disabling this 910 option saves about 6k. 911 912config TOSHIBA 913 tristate "Toshiba Laptop support" 914 depends on X86_32 915 ---help--- 916 This adds a driver to safely access the System Management Mode of 917 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 918 not work on models with a Phoenix BIOS. The System Management Mode 919 is used to set the BIOS and power saving options on Toshiba portables. 920 921 For information on utilities to make use of this driver see the 922 Toshiba Linux utilities web site at: 923 <http://www.buzzard.org.uk/toshiba/>. 924 925 Say Y if you intend to run this kernel on a Toshiba portable. 926 Say N otherwise. 927 928config I8K 929 tristate "Dell laptop support" 930 ---help--- 931 This adds a driver to safely access the System Management Mode 932 of the CPU on the Dell Inspiron 8000. The System Management Mode 933 is used to read cpu temperature and cooling fan status and to 934 control the fans on the I8K portables. 935 936 This driver has been tested only on the Inspiron 8000 but it may 937 also work with other Dell laptops. You can force loading on other 938 models by passing the parameter `force=1' to the module. Use at 939 your own risk. 940 941 For information on utilities to make use of this driver see the 942 I8K Linux utilities web site at: 943 <http://people.debian.org/~dz/i8k/> 944 945 Say Y if you intend to run this kernel on a Dell Inspiron 8000. 946 Say N otherwise. 947 948config X86_REBOOTFIXUPS 949 bool "Enable X86 board specific fixups for reboot" 950 depends on X86_32 951 ---help--- 952 This enables chipset and/or board specific fixups to be done 953 in order to get reboot to work correctly. This is only needed on 954 some combinations of hardware and BIOS. The symptom, for which 955 this config is intended, is when reboot ends with a stalled/hung 956 system. 957 958 Currently, the only fixup is for the Geode machines using 959 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 960 961 Say Y if you want to enable the fixup. Currently, it's safe to 962 enable this option even if you don't need it. 963 Say N otherwise. 964 965config MICROCODE 966 tristate "/dev/cpu/microcode - microcode support" 967 select FW_LOADER 968 ---help--- 969 If you say Y here, you will be able to update the microcode on 970 certain Intel and AMD processors. The Intel support is for the 971 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, 972 Pentium 4, Xeon etc. The AMD support is for family 0x10 and 973 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra. 974 You will obviously need the actual microcode binary data itself 975 which is not shipped with the Linux kernel. 976 977 This option selects the general module only, you need to select 978 at least one vendor specific module as well. 979 980 To compile this driver as a module, choose M here: the 981 module will be called microcode. 982 983config MICROCODE_INTEL 984 bool "Intel microcode patch loading support" 985 depends on MICROCODE 986 default MICROCODE 987 select FW_LOADER 988 ---help--- 989 This options enables microcode patch loading support for Intel 990 processors. 991 992 For latest news and information on obtaining all the required 993 Intel ingredients for this driver, check: 994 <http://www.urbanmyth.org/microcode/>. 995 996config MICROCODE_AMD 997 bool "AMD microcode patch loading support" 998 depends on MICROCODE 999 select FW_LOADER 1000 ---help--- 1001 If you select this option, microcode patch loading support for AMD 1002 processors will be enabled. 1003 1004config MICROCODE_OLD_INTERFACE 1005 def_bool y 1006 depends on MICROCODE 1007 1008config X86_MSR 1009 tristate "/dev/cpu/*/msr - Model-specific register support" 1010 ---help--- 1011 This device gives privileged processes access to the x86 1012 Model-Specific Registers (MSRs). It is a character device with 1013 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1014 MSR accesses are directed to a specific CPU on multi-processor 1015 systems. 1016 1017config X86_CPUID 1018 tristate "/dev/cpu/*/cpuid - CPU information support" 1019 ---help--- 1020 This device gives processes access to the x86 CPUID instruction to 1021 be executed on a specific processor. It is a character device 1022 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1023 /dev/cpu/31/cpuid. 1024 1025choice 1026 prompt "High Memory Support" 1027 default HIGHMEM64G if X86_NUMAQ 1028 default HIGHMEM4G 1029 depends on X86_32 1030 1031config NOHIGHMEM 1032 bool "off" 1033 depends on !X86_NUMAQ 1034 ---help--- 1035 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1036 However, the address space of 32-bit x86 processors is only 4 1037 Gigabytes large. That means that, if you have a large amount of 1038 physical memory, not all of it can be "permanently mapped" by the 1039 kernel. The physical memory that's not permanently mapped is called 1040 "high memory". 1041 1042 If you are compiling a kernel which will never run on a machine with 1043 more than 1 Gigabyte total physical RAM, answer "off" here (default 1044 choice and suitable for most users). This will result in a "3GB/1GB" 1045 split: 3GB are mapped so that each process sees a 3GB virtual memory 1046 space and the remaining part of the 4GB virtual memory space is used 1047 by the kernel to permanently map as much physical memory as 1048 possible. 1049 1050 If the machine has between 1 and 4 Gigabytes physical RAM, then 1051 answer "4GB" here. 1052 1053 If more than 4 Gigabytes is used then answer "64GB" here. This 1054 selection turns Intel PAE (Physical Address Extension) mode on. 1055 PAE implements 3-level paging on IA32 processors. PAE is fully 1056 supported by Linux, PAE mode is implemented on all recent Intel 1057 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1058 then the kernel will not boot on CPUs that don't support PAE! 1059 1060 The actual amount of total physical memory will either be 1061 auto detected or can be forced by using a kernel command line option 1062 such as "mem=256M". (Try "man bootparam" or see the documentation of 1063 your boot loader (lilo or loadlin) about how to pass options to the 1064 kernel at boot time.) 1065 1066 If unsure, say "off". 1067 1068config HIGHMEM4G 1069 bool "4GB" 1070 depends on !X86_NUMAQ 1071 ---help--- 1072 Select this if you have a 32-bit processor and between 1 and 4 1073 gigabytes of physical RAM. 1074 1075config HIGHMEM64G 1076 bool "64GB" 1077 depends on !M386 && !M486 1078 select X86_PAE 1079 ---help--- 1080 Select this if you have a 32-bit processor and more than 4 1081 gigabytes of physical RAM. 1082 1083endchoice 1084 1085choice 1086 depends on EXPERIMENTAL 1087 prompt "Memory split" if EMBEDDED 1088 default VMSPLIT_3G 1089 depends on X86_32 1090 ---help--- 1091 Select the desired split between kernel and user memory. 1092 1093 If the address range available to the kernel is less than the 1094 physical memory installed, the remaining memory will be available 1095 as "high memory". Accessing high memory is a little more costly 1096 than low memory, as it needs to be mapped into the kernel first. 1097 Note that increasing the kernel address space limits the range 1098 available to user programs, making the address space there 1099 tighter. Selecting anything other than the default 3G/1G split 1100 will also likely make your kernel incompatible with binary-only 1101 kernel modules. 1102 1103 If you are not absolutely sure what you are doing, leave this 1104 option alone! 1105 1106 config VMSPLIT_3G 1107 bool "3G/1G user/kernel split" 1108 config VMSPLIT_3G_OPT 1109 depends on !X86_PAE 1110 bool "3G/1G user/kernel split (for full 1G low memory)" 1111 config VMSPLIT_2G 1112 bool "2G/2G user/kernel split" 1113 config VMSPLIT_2G_OPT 1114 depends on !X86_PAE 1115 bool "2G/2G user/kernel split (for full 2G low memory)" 1116 config VMSPLIT_1G 1117 bool "1G/3G user/kernel split" 1118endchoice 1119 1120config PAGE_OFFSET 1121 hex 1122 default 0xB0000000 if VMSPLIT_3G_OPT 1123 default 0x80000000 if VMSPLIT_2G 1124 default 0x78000000 if VMSPLIT_2G_OPT 1125 default 0x40000000 if VMSPLIT_1G 1126 default 0xC0000000 1127 depends on X86_32 1128 1129config HIGHMEM 1130 def_bool y 1131 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1132 1133config X86_PAE 1134 bool "PAE (Physical Address Extension) Support" 1135 depends on X86_32 && !HIGHMEM4G 1136 ---help--- 1137 PAE is required for NX support, and furthermore enables 1138 larger swapspace support for non-overcommit purposes. It 1139 has the cost of more pagetable lookup overhead, and also 1140 consumes more pagetable space per process. 1141 1142config ARCH_PHYS_ADDR_T_64BIT 1143 def_bool X86_64 || X86_PAE 1144 1145config DIRECT_GBPAGES 1146 bool "Enable 1GB pages for kernel pagetables" if EMBEDDED 1147 default y 1148 depends on X86_64 1149 ---help--- 1150 Allow the kernel linear mapping to use 1GB pages on CPUs that 1151 support it. This can improve the kernel's performance a tiny bit by 1152 reducing TLB pressure. If in doubt, say "Y". 1153 1154# Common NUMA Features 1155config NUMA 1156 bool "Numa Memory Allocation and Scheduler Support" 1157 depends on SMP 1158 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL) 1159 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP) 1160 ---help--- 1161 Enable NUMA (Non Uniform Memory Access) support. 1162 1163 The kernel will try to allocate memory used by a CPU on the 1164 local memory controller of the CPU and add some more 1165 NUMA awareness to the kernel. 1166 1167 For 64-bit this is recommended if the system is Intel Core i7 1168 (or later), AMD Opteron, or EM64T NUMA. 1169 1170 For 32-bit this is only needed on (rare) 32-bit-only platforms 1171 that support NUMA topologies, such as NUMAQ / Summit, or if you 1172 boot a 32-bit kernel on a 64-bit NUMA platform. 1173 1174 Otherwise, you should say N. 1175 1176comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI" 1177 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI) 1178 1179config K8_NUMA 1180 def_bool y 1181 prompt "Old style AMD Opteron NUMA detection" 1182 depends on X86_64 && NUMA && PCI 1183 ---help--- 1184 Enable K8 NUMA node topology detection. You should say Y here if 1185 you have a multi processor AMD K8 system. This uses an old 1186 method to read the NUMA configuration directly from the builtin 1187 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA 1188 instead, which also takes priority if both are compiled in. 1189 1190config X86_64_ACPI_NUMA 1191 def_bool y 1192 prompt "ACPI NUMA detection" 1193 depends on X86_64 && NUMA && ACPI && PCI 1194 select ACPI_NUMA 1195 ---help--- 1196 Enable ACPI SRAT based node topology detection. 1197 1198# Some NUMA nodes have memory ranges that span 1199# other nodes. Even though a pfn is valid and 1200# between a node's start and end pfns, it may not 1201# reside on that node. See memmap_init_zone() 1202# for details. 1203config NODES_SPAN_OTHER_NODES 1204 def_bool y 1205 depends on X86_64_ACPI_NUMA 1206 1207config NUMA_EMU 1208 bool "NUMA emulation" 1209 depends on X86_64 && NUMA 1210 ---help--- 1211 Enable NUMA emulation. A flat machine will be split 1212 into virtual nodes when booted with "numa=fake=N", where N is the 1213 number of nodes. This is only useful for debugging. 1214 1215config NODES_SHIFT 1216 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1217 range 1 10 1218 default "10" if MAXSMP 1219 default "6" if X86_64 1220 default "4" if X86_NUMAQ 1221 default "3" 1222 depends on NEED_MULTIPLE_NODES 1223 ---help--- 1224 Specify the maximum number of NUMA Nodes available on the target 1225 system. Increases memory reserved to accommodate various tables. 1226 1227config HAVE_ARCH_BOOTMEM 1228 def_bool y 1229 depends on X86_32 && NUMA 1230 1231config ARCH_HAVE_MEMORY_PRESENT 1232 def_bool y 1233 depends on X86_32 && DISCONTIGMEM 1234 1235config NEED_NODE_MEMMAP_SIZE 1236 def_bool y 1237 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1238 1239config HAVE_ARCH_ALLOC_REMAP 1240 def_bool y 1241 depends on X86_32 && NUMA 1242 1243config ARCH_FLATMEM_ENABLE 1244 def_bool y 1245 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA 1246 1247config ARCH_DISCONTIGMEM_ENABLE 1248 def_bool y 1249 depends on NUMA && X86_32 1250 1251config ARCH_DISCONTIGMEM_DEFAULT 1252 def_bool y 1253 depends on NUMA && X86_32 1254 1255config ARCH_PROC_KCORE_TEXT 1256 def_bool y 1257 depends on X86_64 && PROC_KCORE 1258 1259config ARCH_SPARSEMEM_DEFAULT 1260 def_bool y 1261 depends on X86_64 1262 1263config ARCH_SPARSEMEM_ENABLE 1264 def_bool y 1265 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD 1266 select SPARSEMEM_STATIC if X86_32 1267 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1268 1269config ARCH_SELECT_MEMORY_MODEL 1270 def_bool y 1271 depends on ARCH_SPARSEMEM_ENABLE 1272 1273config ARCH_MEMORY_PROBE 1274 def_bool X86_64 1275 depends on MEMORY_HOTPLUG 1276 1277config ILLEGAL_POINTER_VALUE 1278 hex 1279 default 0 if X86_32 1280 default 0xdead000000000000 if X86_64 1281 1282source "mm/Kconfig" 1283 1284config HIGHPTE 1285 bool "Allocate 3rd-level pagetables from highmem" 1286 depends on HIGHMEM 1287 ---help--- 1288 The VM uses one page table entry for each page of physical memory. 1289 For systems with a lot of RAM, this can be wasteful of precious 1290 low memory. Setting this option will put user-space page table 1291 entries in high memory. 1292 1293config X86_CHECK_BIOS_CORRUPTION 1294 bool "Check for low memory corruption" 1295 ---help--- 1296 Periodically check for memory corruption in low memory, which 1297 is suspected to be caused by BIOS. Even when enabled in the 1298 configuration, it is disabled at runtime. Enable it by 1299 setting "memory_corruption_check=1" on the kernel command 1300 line. By default it scans the low 64k of memory every 60 1301 seconds; see the memory_corruption_check_size and 1302 memory_corruption_check_period parameters in 1303 Documentation/kernel-parameters.txt to adjust this. 1304 1305 When enabled with the default parameters, this option has 1306 almost no overhead, as it reserves a relatively small amount 1307 of memory and scans it infrequently. It both detects corruption 1308 and prevents it from affecting the running system. 1309 1310 It is, however, intended as a diagnostic tool; if repeatable 1311 BIOS-originated corruption always affects the same memory, 1312 you can use memmap= to prevent the kernel from using that 1313 memory. 1314 1315config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1316 bool "Set the default setting of memory_corruption_check" 1317 depends on X86_CHECK_BIOS_CORRUPTION 1318 default y 1319 ---help--- 1320 Set whether the default state of memory_corruption_check is 1321 on or off. 1322 1323config X86_RESERVE_LOW_64K 1324 bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen" 1325 default y 1326 ---help--- 1327 Reserve the first 64K of physical RAM on BIOSes that are known 1328 to potentially corrupt that memory range. A numbers of BIOSes are 1329 known to utilize this area during suspend/resume, so it must not 1330 be used by the kernel. 1331 1332 Set this to N if you are absolutely sure that you trust the BIOS 1333 to get all its memory reservations and usages right. 1334 1335 If you have doubts about the BIOS (e.g. suspend/resume does not 1336 work or there's kernel crashes after certain hardware hotplug 1337 events) and it's not AMI or Phoenix, then you might want to enable 1338 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical 1339 corruption patterns. 1340 1341 Say Y if unsure. 1342 1343config MATH_EMULATION 1344 bool 1345 prompt "Math emulation" if X86_32 1346 ---help--- 1347 Linux can emulate a math coprocessor (used for floating point 1348 operations) if you don't have one. 486DX and Pentium processors have 1349 a math coprocessor built in, 486SX and 386 do not, unless you added 1350 a 487DX or 387, respectively. (The messages during boot time can 1351 give you some hints here ["man dmesg"].) Everyone needs either a 1352 coprocessor or this emulation. 1353 1354 If you don't have a math coprocessor, you need to say Y here; if you 1355 say Y here even though you have a coprocessor, the coprocessor will 1356 be used nevertheless. (This behavior can be changed with the kernel 1357 command line option "no387", which comes handy if your coprocessor 1358 is broken. Try "man bootparam" or see the documentation of your boot 1359 loader (lilo or loadlin) about how to pass options to the kernel at 1360 boot time.) This means that it is a good idea to say Y here if you 1361 intend to use this kernel on different machines. 1362 1363 More information about the internals of the Linux math coprocessor 1364 emulation can be found in <file:arch/x86/math-emu/README>. 1365 1366 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1367 kernel, it won't hurt. 1368 1369config MTRR 1370 def_bool y 1371 prompt "MTRR (Memory Type Range Register) support" if EMBEDDED 1372 ---help--- 1373 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1374 the Memory Type Range Registers (MTRRs) may be used to control 1375 processor access to memory ranges. This is most useful if you have 1376 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1377 allows bus write transfers to be combined into a larger transfer 1378 before bursting over the PCI/AGP bus. This can increase performance 1379 of image write operations 2.5 times or more. Saying Y here creates a 1380 /proc/mtrr file which may be used to manipulate your processor's 1381 MTRRs. Typically the X server should use this. 1382 1383 This code has a reasonably generic interface so that similar 1384 control registers on other processors can be easily supported 1385 as well: 1386 1387 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1388 Registers (ARRs) which provide a similar functionality to MTRRs. For 1389 these, the ARRs are used to emulate the MTRRs. 1390 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1391 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1392 write-combining. All of these processors are supported by this code 1393 and it makes sense to say Y here if you have one of them. 1394 1395 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1396 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1397 can lead to all sorts of problems, so it's good to say Y here. 1398 1399 You can safely say Y even if your machine doesn't have MTRRs, you'll 1400 just add about 9 KB to your kernel. 1401 1402 See <file:Documentation/x86/mtrr.txt> for more information. 1403 1404config MTRR_SANITIZER 1405 def_bool y 1406 prompt "MTRR cleanup support" 1407 depends on MTRR 1408 ---help--- 1409 Convert MTRR layout from continuous to discrete, so X drivers can 1410 add writeback entries. 1411 1412 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1413 The largest mtrr entry size for a continuous block can be set with 1414 mtrr_chunk_size. 1415 1416 If unsure, say Y. 1417 1418config MTRR_SANITIZER_ENABLE_DEFAULT 1419 int "MTRR cleanup enable value (0-1)" 1420 range 0 1 1421 default "0" 1422 depends on MTRR_SANITIZER 1423 ---help--- 1424 Enable mtrr cleanup default value 1425 1426config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1427 int "MTRR cleanup spare reg num (0-7)" 1428 range 0 7 1429 default "1" 1430 depends on MTRR_SANITIZER 1431 ---help--- 1432 mtrr cleanup spare entries default, it can be changed via 1433 mtrr_spare_reg_nr=N on the kernel command line. 1434 1435config X86_PAT 1436 def_bool y 1437 prompt "x86 PAT support" if EMBEDDED 1438 depends on MTRR 1439 ---help--- 1440 Use PAT attributes to setup page level cache control. 1441 1442 PATs are the modern equivalents of MTRRs and are much more 1443 flexible than MTRRs. 1444 1445 Say N here if you see bootup problems (boot crash, boot hang, 1446 spontaneous reboots) or a non-working video driver. 1447 1448 If unsure, say Y. 1449 1450config ARCH_USES_PG_UNCACHED 1451 def_bool y 1452 depends on X86_PAT 1453 1454config EFI 1455 bool "EFI runtime service support" 1456 depends on ACPI 1457 ---help--- 1458 This enables the kernel to use EFI runtime services that are 1459 available (such as the EFI variable services). 1460 1461 This option is only useful on systems that have EFI firmware. 1462 In addition, you should use the latest ELILO loader available 1463 at <http://elilo.sourceforge.net> in order to take advantage 1464 of EFI runtime services. However, even with this option, the 1465 resultant kernel should continue to boot on existing non-EFI 1466 platforms. 1467 1468config SECCOMP 1469 def_bool y 1470 prompt "Enable seccomp to safely compute untrusted bytecode" 1471 ---help--- 1472 This kernel feature is useful for number crunching applications 1473 that may need to compute untrusted bytecode during their 1474 execution. By using pipes or other transports made available to 1475 the process as file descriptors supporting the read/write 1476 syscalls, it's possible to isolate those applications in 1477 their own address space using seccomp. Once seccomp is 1478 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1479 and the task is only allowed to execute a few safe syscalls 1480 defined by each seccomp mode. 1481 1482 If unsure, say Y. Only embedded should say N here. 1483 1484config CC_STACKPROTECTOR 1485 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)" 1486 ---help--- 1487 This option turns on the -fstack-protector GCC feature. This 1488 feature puts, at the beginning of functions, a canary value on 1489 the stack just before the return address, and validates 1490 the value just before actually returning. Stack based buffer 1491 overflows (that need to overwrite this return address) now also 1492 overwrite the canary, which gets detected and the attack is then 1493 neutralized via a kernel panic. 1494 1495 This feature requires gcc version 4.2 or above, or a distribution 1496 gcc with the feature backported. Older versions are automatically 1497 detected and for those versions, this configuration option is 1498 ignored. (and a warning is printed during bootup) 1499 1500source kernel/Kconfig.hz 1501 1502config KEXEC 1503 bool "kexec system call" 1504 ---help--- 1505 kexec is a system call that implements the ability to shutdown your 1506 current kernel, and to start another kernel. It is like a reboot 1507 but it is independent of the system firmware. And like a reboot 1508 you can start any kernel with it, not just Linux. 1509 1510 The name comes from the similarity to the exec system call. 1511 1512 It is an ongoing process to be certain the hardware in a machine 1513 is properly shutdown, so do not be surprised if this code does not 1514 initially work for you. It may help to enable device hotplugging 1515 support. As of this writing the exact hardware interface is 1516 strongly in flux, so no good recommendation can be made. 1517 1518config CRASH_DUMP 1519 bool "kernel crash dumps" 1520 depends on X86_64 || (X86_32 && HIGHMEM) 1521 ---help--- 1522 Generate crash dump after being started by kexec. 1523 This should be normally only set in special crash dump kernels 1524 which are loaded in the main kernel with kexec-tools into 1525 a specially reserved region and then later executed after 1526 a crash by kdump/kexec. The crash dump kernel must be compiled 1527 to a memory address not used by the main kernel or BIOS using 1528 PHYSICAL_START, or it must be built as a relocatable image 1529 (CONFIG_RELOCATABLE=y). 1530 For more details see Documentation/kdump/kdump.txt 1531 1532config KEXEC_JUMP 1533 bool "kexec jump (EXPERIMENTAL)" 1534 depends on EXPERIMENTAL 1535 depends on KEXEC && HIBERNATION 1536 ---help--- 1537 Jump between original kernel and kexeced kernel and invoke 1538 code in physical address mode via KEXEC 1539 1540config PHYSICAL_START 1541 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP) 1542 default "0x1000000" 1543 ---help--- 1544 This gives the physical address where the kernel is loaded. 1545 1546 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1547 bzImage will decompress itself to above physical address and 1548 run from there. Otherwise, bzImage will run from the address where 1549 it has been loaded by the boot loader and will ignore above physical 1550 address. 1551 1552 In normal kdump cases one does not have to set/change this option 1553 as now bzImage can be compiled as a completely relocatable image 1554 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1555 address. This option is mainly useful for the folks who don't want 1556 to use a bzImage for capturing the crash dump and want to use a 1557 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1558 to be specifically compiled to run from a specific memory area 1559 (normally a reserved region) and this option comes handy. 1560 1561 So if you are using bzImage for capturing the crash dump, 1562 leave the value here unchanged to 0x1000000 and set 1563 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1564 for capturing the crash dump change this value to start of 1565 the reserved region. In other words, it can be set based on 1566 the "X" value as specified in the "crashkernel=YM@XM" 1567 command line boot parameter passed to the panic-ed 1568 kernel. Please take a look at Documentation/kdump/kdump.txt 1569 for more details about crash dumps. 1570 1571 Usage of bzImage for capturing the crash dump is recommended as 1572 one does not have to build two kernels. Same kernel can be used 1573 as production kernel and capture kernel. Above option should have 1574 gone away after relocatable bzImage support is introduced. But it 1575 is present because there are users out there who continue to use 1576 vmlinux for dump capture. This option should go away down the 1577 line. 1578 1579 Don't change this unless you know what you are doing. 1580 1581config RELOCATABLE 1582 bool "Build a relocatable kernel" 1583 default y 1584 ---help--- 1585 This builds a kernel image that retains relocation information 1586 so it can be loaded someplace besides the default 1MB. 1587 The relocations tend to make the kernel binary about 10% larger, 1588 but are discarded at runtime. 1589 1590 One use is for the kexec on panic case where the recovery kernel 1591 must live at a different physical address than the primary 1592 kernel. 1593 1594 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1595 it has been loaded at and the compile time physical address 1596 (CONFIG_PHYSICAL_START) is ignored. 1597 1598# Relocation on x86-32 needs some additional build support 1599config X86_NEED_RELOCS 1600 def_bool y 1601 depends on X86_32 && RELOCATABLE 1602 1603config PHYSICAL_ALIGN 1604 hex "Alignment value to which kernel should be aligned" if X86_32 1605 default "0x1000000" 1606 range 0x2000 0x1000000 1607 ---help--- 1608 This value puts the alignment restrictions on physical address 1609 where kernel is loaded and run from. Kernel is compiled for an 1610 address which meets above alignment restriction. 1611 1612 If bootloader loads the kernel at a non-aligned address and 1613 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1614 address aligned to above value and run from there. 1615 1616 If bootloader loads the kernel at a non-aligned address and 1617 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1618 load address and decompress itself to the address it has been 1619 compiled for and run from there. The address for which kernel is 1620 compiled already meets above alignment restrictions. Hence the 1621 end result is that kernel runs from a physical address meeting 1622 above alignment restrictions. 1623 1624 Don't change this unless you know what you are doing. 1625 1626config HOTPLUG_CPU 1627 bool "Support for hot-pluggable CPUs" 1628 depends on SMP && HOTPLUG 1629 ---help--- 1630 Say Y here to allow turning CPUs off and on. CPUs can be 1631 controlled through /sys/devices/system/cpu. 1632 ( Note: power management support will enable this option 1633 automatically on SMP systems. ) 1634 Say N if you want to disable CPU hotplug. 1635 1636config COMPAT_VDSO 1637 def_bool y 1638 prompt "Compat VDSO support" 1639 depends on X86_32 || IA32_EMULATION 1640 ---help--- 1641 Map the 32-bit VDSO to the predictable old-style address too. 1642 1643 Say N here if you are running a sufficiently recent glibc 1644 version (2.3.3 or later), to remove the high-mapped 1645 VDSO mapping and to exclusively use the randomized VDSO. 1646 1647 If unsure, say Y. 1648 1649config CMDLINE_BOOL 1650 bool "Built-in kernel command line" 1651 ---help--- 1652 Allow for specifying boot arguments to the kernel at 1653 build time. On some systems (e.g. embedded ones), it is 1654 necessary or convenient to provide some or all of the 1655 kernel boot arguments with the kernel itself (that is, 1656 to not rely on the boot loader to provide them.) 1657 1658 To compile command line arguments into the kernel, 1659 set this option to 'Y', then fill in the 1660 the boot arguments in CONFIG_CMDLINE. 1661 1662 Systems with fully functional boot loaders (i.e. non-embedded) 1663 should leave this option set to 'N'. 1664 1665config CMDLINE 1666 string "Built-in kernel command string" 1667 depends on CMDLINE_BOOL 1668 default "" 1669 ---help--- 1670 Enter arguments here that should be compiled into the kernel 1671 image and used at boot time. If the boot loader provides a 1672 command line at boot time, it is appended to this string to 1673 form the full kernel command line, when the system boots. 1674 1675 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 1676 change this behavior. 1677 1678 In most cases, the command line (whether built-in or provided 1679 by the boot loader) should specify the device for the root 1680 file system. 1681 1682config CMDLINE_OVERRIDE 1683 bool "Built-in command line overrides boot loader arguments" 1684 depends on CMDLINE_BOOL 1685 ---help--- 1686 Set this option to 'Y' to have the kernel ignore the boot loader 1687 command line, and use ONLY the built-in command line. 1688 1689 This is used to work around broken boot loaders. This should 1690 be set to 'N' under normal conditions. 1691 1692endmenu 1693 1694config ARCH_ENABLE_MEMORY_HOTPLUG 1695 def_bool y 1696 depends on X86_64 || (X86_32 && HIGHMEM) 1697 1698config ARCH_ENABLE_MEMORY_HOTREMOVE 1699 def_bool y 1700 depends on MEMORY_HOTPLUG 1701 1702config HAVE_ARCH_EARLY_PFN_TO_NID 1703 def_bool X86_64 1704 depends on NUMA 1705 1706config USE_PERCPU_NUMA_NODE_ID 1707 def_bool X86_64 1708 depends on NUMA 1709 1710menu "Power management and ACPI options" 1711 1712config ARCH_HIBERNATION_HEADER 1713 def_bool y 1714 depends on X86_64 && HIBERNATION 1715 1716source "kernel/power/Kconfig" 1717 1718source "drivers/acpi/Kconfig" 1719 1720source "drivers/sfi/Kconfig" 1721 1722config X86_APM_BOOT 1723 def_bool y 1724 depends on APM || APM_MODULE 1725 1726menuconfig APM 1727 tristate "APM (Advanced Power Management) BIOS support" 1728 depends on X86_32 && PM_SLEEP 1729 ---help--- 1730 APM is a BIOS specification for saving power using several different 1731 techniques. This is mostly useful for battery powered laptops with 1732 APM compliant BIOSes. If you say Y here, the system time will be 1733 reset after a RESUME operation, the /proc/apm device will provide 1734 battery status information, and user-space programs will receive 1735 notification of APM "events" (e.g. battery status change). 1736 1737 If you select "Y" here, you can disable actual use of the APM 1738 BIOS by passing the "apm=off" option to the kernel at boot time. 1739 1740 Note that the APM support is almost completely disabled for 1741 machines with more than one CPU. 1742 1743 In order to use APM, you will need supporting software. For location 1744 and more information, read <file:Documentation/power/pm.txt> and the 1745 Battery Powered Linux mini-HOWTO, available from 1746 <http://www.tldp.org/docs.html#howto>. 1747 1748 This driver does not spin down disk drives (see the hdparm(8) 1749 manpage ("man 8 hdparm") for that), and it doesn't turn off 1750 VESA-compliant "green" monitors. 1751 1752 This driver does not support the TI 4000M TravelMate and the ACER 1753 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1754 desktop machines also don't have compliant BIOSes, and this driver 1755 may cause those machines to panic during the boot phase. 1756 1757 Generally, if you don't have a battery in your machine, there isn't 1758 much point in using this driver and you should say N. If you get 1759 random kernel OOPSes or reboots that don't seem to be related to 1760 anything, try disabling/enabling this option (or disabling/enabling 1761 APM in your BIOS). 1762 1763 Some other things you should try when experiencing seemingly random, 1764 "weird" problems: 1765 1766 1) make sure that you have enough swap space and that it is 1767 enabled. 1768 2) pass the "no-hlt" option to the kernel 1769 3) switch on floating point emulation in the kernel and pass 1770 the "no387" option to the kernel 1771 4) pass the "floppy=nodma" option to the kernel 1772 5) pass the "mem=4M" option to the kernel (thereby disabling 1773 all but the first 4 MB of RAM) 1774 6) make sure that the CPU is not over clocked. 1775 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1776 8) disable the cache from your BIOS settings 1777 9) install a fan for the video card or exchange video RAM 1778 10) install a better fan for the CPU 1779 11) exchange RAM chips 1780 12) exchange the motherboard. 1781 1782 To compile this driver as a module, choose M here: the 1783 module will be called apm. 1784 1785if APM 1786 1787config APM_IGNORE_USER_SUSPEND 1788 bool "Ignore USER SUSPEND" 1789 ---help--- 1790 This option will ignore USER SUSPEND requests. On machines with a 1791 compliant APM BIOS, you want to say N. However, on the NEC Versa M 1792 series notebooks, it is necessary to say Y because of a BIOS bug. 1793 1794config APM_DO_ENABLE 1795 bool "Enable PM at boot time" 1796 ---help--- 1797 Enable APM features at boot time. From page 36 of the APM BIOS 1798 specification: "When disabled, the APM BIOS does not automatically 1799 power manage devices, enter the Standby State, enter the Suspend 1800 State, or take power saving steps in response to CPU Idle calls." 1801 This driver will make CPU Idle calls when Linux is idle (unless this 1802 feature is turned off -- see "Do CPU IDLE calls", below). This 1803 should always save battery power, but more complicated APM features 1804 will be dependent on your BIOS implementation. You may need to turn 1805 this option off if your computer hangs at boot time when using APM 1806 support, or if it beeps continuously instead of suspending. Turn 1807 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1808 T400CDT. This is off by default since most machines do fine without 1809 this feature. 1810 1811config APM_CPU_IDLE 1812 bool "Make CPU Idle calls when idle" 1813 ---help--- 1814 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 1815 On some machines, this can activate improved power savings, such as 1816 a slowed CPU clock rate, when the machine is idle. These idle calls 1817 are made after the idle loop has run for some length of time (e.g., 1818 333 mS). On some machines, this will cause a hang at boot time or 1819 whenever the CPU becomes idle. (On machines with more than one CPU, 1820 this option does nothing.) 1821 1822config APM_DISPLAY_BLANK 1823 bool "Enable console blanking using APM" 1824 ---help--- 1825 Enable console blanking using the APM. Some laptops can use this to 1826 turn off the LCD backlight when the screen blanker of the Linux 1827 virtual console blanks the screen. Note that this is only used by 1828 the virtual console screen blanker, and won't turn off the backlight 1829 when using the X Window system. This also doesn't have anything to 1830 do with your VESA-compliant power-saving monitor. Further, this 1831 option doesn't work for all laptops -- it might not turn off your 1832 backlight at all, or it might print a lot of errors to the console, 1833 especially if you are using gpm. 1834 1835config APM_ALLOW_INTS 1836 bool "Allow interrupts during APM BIOS calls" 1837 ---help--- 1838 Normally we disable external interrupts while we are making calls to 1839 the APM BIOS as a measure to lessen the effects of a badly behaving 1840 BIOS implementation. The BIOS should reenable interrupts if it 1841 needs to. Unfortunately, some BIOSes do not -- especially those in 1842 many of the newer IBM Thinkpads. If you experience hangs when you 1843 suspend, try setting this to Y. Otherwise, say N. 1844 1845endif # APM 1846 1847source "arch/x86/kernel/cpu/cpufreq/Kconfig" 1848 1849source "drivers/cpuidle/Kconfig" 1850 1851source "drivers/idle/Kconfig" 1852 1853endmenu 1854 1855 1856menu "Bus options (PCI etc.)" 1857 1858config PCI 1859 bool "PCI support" 1860 default y 1861 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC) 1862 ---help--- 1863 Find out whether you have a PCI motherboard. PCI is the name of a 1864 bus system, i.e. the way the CPU talks to the other stuff inside 1865 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 1866 VESA. If you have PCI, say Y, otherwise N. 1867 1868choice 1869 prompt "PCI access mode" 1870 depends on X86_32 && PCI 1871 default PCI_GOANY 1872 ---help--- 1873 On PCI systems, the BIOS can be used to detect the PCI devices and 1874 determine their configuration. However, some old PCI motherboards 1875 have BIOS bugs and may crash if this is done. Also, some embedded 1876 PCI-based systems don't have any BIOS at all. Linux can also try to 1877 detect the PCI hardware directly without using the BIOS. 1878 1879 With this option, you can specify how Linux should detect the 1880 PCI devices. If you choose "BIOS", the BIOS will be used, 1881 if you choose "Direct", the BIOS won't be used, and if you 1882 choose "MMConfig", then PCI Express MMCONFIG will be used. 1883 If you choose "Any", the kernel will try MMCONFIG, then the 1884 direct access method and falls back to the BIOS if that doesn't 1885 work. If unsure, go with the default, which is "Any". 1886 1887config PCI_GOBIOS 1888 bool "BIOS" 1889 1890config PCI_GOMMCONFIG 1891 bool "MMConfig" 1892 1893config PCI_GODIRECT 1894 bool "Direct" 1895 1896config PCI_GOOLPC 1897 bool "OLPC" 1898 depends on OLPC 1899 1900config PCI_GOANY 1901 bool "Any" 1902 1903endchoice 1904 1905config PCI_BIOS 1906 def_bool y 1907 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 1908 1909# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 1910config PCI_DIRECT 1911 def_bool y 1912 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC)) 1913 1914config PCI_MMCONFIG 1915 def_bool y 1916 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 1917 1918config PCI_OLPC 1919 def_bool y 1920 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 1921 1922config PCI_DOMAINS 1923 def_bool y 1924 depends on PCI 1925 1926config PCI_MMCONFIG 1927 bool "Support mmconfig PCI config space access" 1928 depends on X86_64 && PCI && ACPI 1929 1930config PCI_CNB20LE_QUIRK 1931 bool "Read CNB20LE Host Bridge Windows" 1932 depends on PCI 1933 help 1934 Read the PCI windows out of the CNB20LE host bridge. This allows 1935 PCI hotplug to work on systems with the CNB20LE chipset which do 1936 not have ACPI. 1937 1938config DMAR 1939 bool "Support for DMA Remapping Devices (EXPERIMENTAL)" 1940 depends on PCI_MSI && ACPI && EXPERIMENTAL 1941 help 1942 DMA remapping (DMAR) devices support enables independent address 1943 translations for Direct Memory Access (DMA) from devices. 1944 These DMA remapping devices are reported via ACPI tables 1945 and include PCI device scope covered by these DMA 1946 remapping devices. 1947 1948config DMAR_DEFAULT_ON 1949 def_bool y 1950 prompt "Enable DMA Remapping Devices by default" 1951 depends on DMAR 1952 help 1953 Selecting this option will enable a DMAR device at boot time if 1954 one is found. If this option is not selected, DMAR support can 1955 be enabled by passing intel_iommu=on to the kernel. It is 1956 recommended you say N here while the DMAR code remains 1957 experimental. 1958 1959config DMAR_BROKEN_GFX_WA 1960 bool "Workaround broken graphics drivers (going away soon)" 1961 depends on DMAR && BROKEN 1962 ---help--- 1963 Current Graphics drivers tend to use physical address 1964 for DMA and avoid using DMA APIs. Setting this config 1965 option permits the IOMMU driver to set a unity map for 1966 all the OS-visible memory. Hence the driver can continue 1967 to use physical addresses for DMA, at least until this 1968 option is removed in the 2.6.32 kernel. 1969 1970config DMAR_FLOPPY_WA 1971 def_bool y 1972 depends on DMAR 1973 ---help--- 1974 Floppy disk drivers are known to bypass DMA API calls 1975 thereby failing to work when IOMMU is enabled. This 1976 workaround will setup a 1:1 mapping for the first 1977 16MiB to make floppy (an ISA device) work. 1978 1979config INTR_REMAP 1980 bool "Support for Interrupt Remapping (EXPERIMENTAL)" 1981 depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL 1982 ---help--- 1983 Supports Interrupt remapping for IO-APIC and MSI devices. 1984 To use x2apic mode in the CPU's which support x2APIC enhancements or 1985 to support platforms with CPU's having > 8 bit APIC ID, say Y. 1986 1987source "drivers/pci/pcie/Kconfig" 1988 1989source "drivers/pci/Kconfig" 1990 1991# x86_64 have no ISA slots, but do have ISA-style DMA. 1992config ISA_DMA_API 1993 def_bool y 1994 1995if X86_32 1996 1997config ISA 1998 bool "ISA support" 1999 ---help--- 2000 Find out whether you have ISA slots on your motherboard. ISA is the 2001 name of a bus system, i.e. the way the CPU talks to the other stuff 2002 inside your box. Other bus systems are PCI, EISA, MicroChannel 2003 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2004 newer boards don't support it. If you have ISA, say Y, otherwise N. 2005 2006config EISA 2007 bool "EISA support" 2008 depends on ISA 2009 ---help--- 2010 The Extended Industry Standard Architecture (EISA) bus was 2011 developed as an open alternative to the IBM MicroChannel bus. 2012 2013 The EISA bus provided some of the features of the IBM MicroChannel 2014 bus while maintaining backward compatibility with cards made for 2015 the older ISA bus. The EISA bus saw limited use between 1988 and 2016 1995 when it was made obsolete by the PCI bus. 2017 2018 Say Y here if you are building a kernel for an EISA-based machine. 2019 2020 Otherwise, say N. 2021 2022source "drivers/eisa/Kconfig" 2023 2024config MCA 2025 bool "MCA support" 2026 ---help--- 2027 MicroChannel Architecture is found in some IBM PS/2 machines and 2028 laptops. It is a bus system similar to PCI or ISA. See 2029 <file:Documentation/mca.txt> (and especially the web page given 2030 there) before attempting to build an MCA bus kernel. 2031 2032source "drivers/mca/Kconfig" 2033 2034config SCx200 2035 tristate "NatSemi SCx200 support" 2036 ---help--- 2037 This provides basic support for National Semiconductor's 2038 (now AMD's) Geode processors. The driver probes for the 2039 PCI-IDs of several on-chip devices, so its a good dependency 2040 for other scx200_* drivers. 2041 2042 If compiled as a module, the driver is named scx200. 2043 2044config SCx200HR_TIMER 2045 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2046 depends on SCx200 && GENERIC_TIME 2047 default y 2048 ---help--- 2049 This driver provides a clocksource built upon the on-chip 2050 27MHz high-resolution timer. Its also a workaround for 2051 NSC Geode SC-1100's buggy TSC, which loses time when the 2052 processor goes idle (as is done by the scheduler). The 2053 other workaround is idle=poll boot option. 2054 2055config OLPC 2056 bool "One Laptop Per Child support" 2057 select GPIOLIB 2058 ---help--- 2059 Add support for detecting the unique features of the OLPC 2060 XO hardware. 2061 2062endif # X86_32 2063 2064config K8_NB 2065 def_bool y 2066 depends on CPU_SUP_AMD && PCI 2067 2068source "drivers/pcmcia/Kconfig" 2069 2070source "drivers/pci/hotplug/Kconfig" 2071 2072endmenu 2073 2074 2075menu "Executable file formats / Emulations" 2076 2077source "fs/Kconfig.binfmt" 2078 2079config IA32_EMULATION 2080 bool "IA32 Emulation" 2081 depends on X86_64 2082 select COMPAT_BINFMT_ELF 2083 ---help--- 2084 Include code to run 32-bit programs under a 64-bit kernel. You should 2085 likely turn this on, unless you're 100% sure that you don't have any 2086 32-bit programs left. 2087 2088config IA32_AOUT 2089 tristate "IA32 a.out support" 2090 depends on IA32_EMULATION 2091 ---help--- 2092 Support old a.out binaries in the 32bit emulation. 2093 2094config COMPAT 2095 def_bool y 2096 depends on IA32_EMULATION 2097 2098config COMPAT_FOR_U64_ALIGNMENT 2099 def_bool COMPAT 2100 depends on X86_64 2101 2102config SYSVIPC_COMPAT 2103 def_bool y 2104 depends on COMPAT && SYSVIPC 2105 2106endmenu 2107 2108 2109config HAVE_ATOMIC_IOMAP 2110 def_bool y 2111 depends on X86_32 2112 2113source "net/Kconfig" 2114 2115source "drivers/Kconfig" 2116 2117source "drivers/firmware/Kconfig" 2118 2119source "fs/Kconfig" 2120 2121source "arch/x86/Kconfig.debug" 2122 2123source "security/Kconfig" 2124 2125source "crypto/Kconfig" 2126 2127source "arch/x86/kvm/Kconfig" 2128 2129source "lib/Kconfig" 2130