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 HAVE_PERF_EVENTS_NMI 59 select ANON_INODES 60 select HAVE_ARCH_KMEMCHECK 61 select HAVE_USER_RETURN_NOTIFIER 62 63config INSTRUCTION_DECODER 64 def_bool (KPROBES || PERF_EVENTS) 65 66config OUTPUT_FORMAT 67 string 68 default "elf32-i386" if X86_32 69 default "elf64-x86-64" if X86_64 70 71config ARCH_DEFCONFIG 72 string 73 default "arch/x86/configs/i386_defconfig" if X86_32 74 default "arch/x86/configs/x86_64_defconfig" if X86_64 75 76config GENERIC_CMOS_UPDATE 77 def_bool y 78 79config CLOCKSOURCE_WATCHDOG 80 def_bool y 81 82config GENERIC_CLOCKEVENTS 83 def_bool y 84 85config GENERIC_CLOCKEVENTS_BROADCAST 86 def_bool y 87 depends on X86_64 || (X86_32 && X86_LOCAL_APIC) 88 89config LOCKDEP_SUPPORT 90 def_bool y 91 92config STACKTRACE_SUPPORT 93 def_bool y 94 95config HAVE_LATENCYTOP_SUPPORT 96 def_bool y 97 98config MMU 99 def_bool y 100 101config ZONE_DMA 102 def_bool y 103 104config SBUS 105 bool 106 107config NEED_DMA_MAP_STATE 108 def_bool (X86_64 || DMAR || DMA_API_DEBUG) 109 110config NEED_SG_DMA_LENGTH 111 def_bool y 112 113config GENERIC_ISA_DMA 114 def_bool y 115 116config GENERIC_IOMAP 117 def_bool y 118 119config GENERIC_BUG 120 def_bool y 121 depends on BUG 122 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 123 124config GENERIC_BUG_RELATIVE_POINTERS 125 bool 126 127config GENERIC_HWEIGHT 128 def_bool y 129 130config GENERIC_GPIO 131 bool 132 133config ARCH_MAY_HAVE_PC_FDC 134 def_bool y 135 136config RWSEM_GENERIC_SPINLOCK 137 def_bool !X86_XADD 138 139config RWSEM_XCHGADD_ALGORITHM 140 def_bool X86_XADD 141 142config ARCH_HAS_CPU_IDLE_WAIT 143 def_bool y 144 145config GENERIC_CALIBRATE_DELAY 146 def_bool y 147 148config GENERIC_TIME_VSYSCALL 149 bool 150 default X86_64 151 152config ARCH_HAS_CPU_RELAX 153 def_bool y 154 155config ARCH_HAS_DEFAULT_IDLE 156 def_bool y 157 158config ARCH_HAS_CACHE_LINE_SIZE 159 def_bool y 160 161config HAVE_SETUP_PER_CPU_AREA 162 def_bool y 163 164config NEED_PER_CPU_EMBED_FIRST_CHUNK 165 def_bool y 166 167config NEED_PER_CPU_PAGE_FIRST_CHUNK 168 def_bool y 169 170config HAVE_CPUMASK_OF_CPU_MAP 171 def_bool X86_64_SMP 172 173config ARCH_HIBERNATION_POSSIBLE 174 def_bool y 175 176config ARCH_SUSPEND_POSSIBLE 177 def_bool y 178 179config ZONE_DMA32 180 bool 181 default X86_64 182 183config ARCH_POPULATES_NODE_MAP 184 def_bool y 185 186config AUDIT_ARCH 187 bool 188 default X86_64 189 190config ARCH_SUPPORTS_OPTIMIZED_INLINING 191 def_bool y 192 193config ARCH_SUPPORTS_DEBUG_PAGEALLOC 194 def_bool y 195 196config HAVE_EARLY_RES 197 def_bool y 198 199config HAVE_INTEL_TXT 200 def_bool y 201 depends on EXPERIMENTAL && DMAR && ACPI 202 203# Use the generic interrupt handling code in kernel/irq/: 204config GENERIC_HARDIRQS 205 def_bool y 206 207config GENERIC_HARDIRQS_NO__DO_IRQ 208 def_bool y 209 210config GENERIC_IRQ_PROBE 211 def_bool y 212 213config GENERIC_PENDING_IRQ 214 def_bool y 215 depends on GENERIC_HARDIRQS && SMP 216 217config USE_GENERIC_SMP_HELPERS 218 def_bool y 219 depends on SMP 220 221config X86_32_SMP 222 def_bool y 223 depends on X86_32 && SMP 224 225config X86_64_SMP 226 def_bool y 227 depends on X86_64 && SMP 228 229config X86_HT 230 def_bool y 231 depends on SMP 232 233config X86_TRAMPOLINE 234 def_bool y 235 depends on SMP || (64BIT && ACPI_SLEEP) 236 237config X86_32_LAZY_GS 238 def_bool y 239 depends on X86_32 && !CC_STACKPROTECTOR 240 241config ARCH_HWEIGHT_CFLAGS 242 string 243 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32 244 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_64 245 246config KTIME_SCALAR 247 def_bool X86_32 248source "init/Kconfig" 249source "kernel/Kconfig.freezer" 250 251menu "Processor type and features" 252 253source "kernel/time/Kconfig" 254 255config SMP 256 bool "Symmetric multi-processing support" 257 ---help--- 258 This enables support for systems with more than one CPU. If you have 259 a system with only one CPU, like most personal computers, say N. If 260 you have a system with more than one CPU, say Y. 261 262 If you say N here, the kernel will run on single and multiprocessor 263 machines, but will use only one CPU of a multiprocessor machine. If 264 you say Y here, the kernel will run on many, but not all, 265 singleprocessor machines. On a singleprocessor machine, the kernel 266 will run faster if you say N here. 267 268 Note that if you say Y here and choose architecture "586" or 269 "Pentium" under "Processor family", the kernel will not work on 486 270 architectures. Similarly, multiprocessor kernels for the "PPro" 271 architecture may not work on all Pentium based boards. 272 273 People using multiprocessor machines who say Y here should also say 274 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 275 Management" code will be disabled if you say Y here. 276 277 See also <file:Documentation/i386/IO-APIC.txt>, 278 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 279 <http://www.tldp.org/docs.html#howto>. 280 281 If you don't know what to do here, say N. 282 283config X86_X2APIC 284 bool "Support x2apic" 285 depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP 286 ---help--- 287 This enables x2apic support on CPUs that have this feature. 288 289 This allows 32-bit apic IDs (so it can support very large systems), 290 and accesses the local apic via MSRs not via mmio. 291 292 If you don't know what to do here, say N. 293 294config SPARSE_IRQ 295 bool "Support sparse irq numbering" 296 depends on PCI_MSI || HT_IRQ 297 ---help--- 298 This enables support for sparse irqs. This is useful for distro 299 kernels that want to define a high CONFIG_NR_CPUS value but still 300 want to have low kernel memory footprint on smaller machines. 301 302 ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread 303 out the irq_desc[] array in a more NUMA-friendly way. ) 304 305 If you don't know what to do here, say N. 306 307config NUMA_IRQ_DESC 308 def_bool y 309 depends on SPARSE_IRQ && NUMA 310 311config X86_MPPARSE 312 bool "Enable MPS table" if ACPI 313 default y 314 depends on X86_LOCAL_APIC 315 ---help--- 316 For old smp systems that do not have proper acpi support. Newer systems 317 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 318 319config X86_BIGSMP 320 bool "Support for big SMP systems with more than 8 CPUs" 321 depends on X86_32 && SMP 322 ---help--- 323 This option is needed for the systems that have more than 8 CPUs 324 325if X86_32 326config X86_EXTENDED_PLATFORM 327 bool "Support for extended (non-PC) x86 platforms" 328 default y 329 ---help--- 330 If you disable this option then the kernel will only support 331 standard PC platforms. (which covers the vast majority of 332 systems out there.) 333 334 If you enable this option then you'll be able to select support 335 for the following (non-PC) 32 bit x86 platforms: 336 AMD Elan 337 NUMAQ (IBM/Sequent) 338 RDC R-321x SoC 339 SGI 320/540 (Visual Workstation) 340 Summit/EXA (IBM x440) 341 Unisys ES7000 IA32 series 342 Moorestown MID devices 343 344 If you have one of these systems, or if you want to build a 345 generic distribution kernel, say Y here - otherwise say N. 346endif 347 348if X86_64 349config X86_EXTENDED_PLATFORM 350 bool "Support for extended (non-PC) x86 platforms" 351 default y 352 ---help--- 353 If you disable this option then the kernel will only support 354 standard PC platforms. (which covers the vast majority of 355 systems out there.) 356 357 If you enable this option then you'll be able to select support 358 for the following (non-PC) 64 bit x86 platforms: 359 ScaleMP vSMP 360 SGI Ultraviolet 361 362 If you have one of these systems, or if you want to build a 363 generic distribution kernel, say Y here - otherwise say N. 364endif 365# This is an alphabetically sorted list of 64 bit extended platforms 366# Please maintain the alphabetic order if and when there are additions 367 368config X86_VSMP 369 bool "ScaleMP vSMP" 370 select PARAVIRT 371 depends on X86_64 && PCI 372 depends on X86_EXTENDED_PLATFORM 373 ---help--- 374 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 375 supposed to run on these EM64T-based machines. Only choose this option 376 if you have one of these machines. 377 378config X86_UV 379 bool "SGI Ultraviolet" 380 depends on X86_64 381 depends on X86_EXTENDED_PLATFORM 382 depends on NUMA 383 depends on X86_X2APIC 384 ---help--- 385 This option is needed in order to support SGI Ultraviolet systems. 386 If you don't have one of these, you should say N here. 387 388# Following is an alphabetically sorted list of 32 bit extended platforms 389# Please maintain the alphabetic order if and when there are additions 390 391config X86_ELAN 392 bool "AMD Elan" 393 depends on X86_32 394 depends on X86_EXTENDED_PLATFORM 395 ---help--- 396 Select this for an AMD Elan processor. 397 398 Do not use this option for K6/Athlon/Opteron processors! 399 400 If unsure, choose "PC-compatible" instead. 401 402config X86_MRST 403 bool "Moorestown MID platform" 404 depends on PCI 405 depends on PCI_GOANY 406 depends on X86_32 407 depends on X86_EXTENDED_PLATFORM 408 depends on X86_IO_APIC 409 select APB_TIMER 410 ---help--- 411 Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin 412 Internet Device(MID) platform. Moorestown consists of two chips: 413 Lincroft (CPU core, graphics, and memory controller) and Langwell IOH. 414 Unlike standard x86 PCs, Moorestown does not have many legacy devices 415 nor standard legacy replacement devices/features. e.g. Moorestown does 416 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports. 417 418config X86_RDC321X 419 bool "RDC R-321x SoC" 420 depends on X86_32 421 depends on X86_EXTENDED_PLATFORM 422 select M486 423 select X86_REBOOTFIXUPS 424 ---help--- 425 This option is needed for RDC R-321x system-on-chip, also known 426 as R-8610-(G). 427 If you don't have one of these chips, you should say N here. 428 429config X86_32_NON_STANDARD 430 bool "Support non-standard 32-bit SMP architectures" 431 depends on X86_32 && SMP 432 depends on X86_EXTENDED_PLATFORM 433 ---help--- 434 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default 435 subarchitectures. It is intended for a generic binary kernel. 436 if you select them all, kernel will probe it one by one. and will 437 fallback to default. 438 439# Alphabetically sorted list of Non standard 32 bit platforms 440 441config X86_NUMAQ 442 bool "NUMAQ (IBM/Sequent)" 443 depends on X86_32_NON_STANDARD 444 depends on PCI 445 select NUMA 446 select X86_MPPARSE 447 ---help--- 448 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent) 449 NUMA multiquad box. This changes the way that processors are 450 bootstrapped, and uses Clustered Logical APIC addressing mode instead 451 of Flat Logical. You will need a new lynxer.elf file to flash your 452 firmware with - send email to <Martin.Bligh@us.ibm.com>. 453 454config X86_SUPPORTS_MEMORY_FAILURE 455 def_bool y 456 # MCE code calls memory_failure(): 457 depends on X86_MCE 458 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 459 depends on !X86_NUMAQ 460 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 461 depends on X86_64 || !SPARSEMEM 462 select ARCH_SUPPORTS_MEMORY_FAILURE 463 464config X86_VISWS 465 bool "SGI 320/540 (Visual Workstation)" 466 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT 467 depends on X86_32_NON_STANDARD 468 ---help--- 469 The SGI Visual Workstation series is an IA32-based workstation 470 based on SGI systems chips with some legacy PC hardware attached. 471 472 Say Y here to create a kernel to run on the SGI 320 or 540. 473 474 A kernel compiled for the Visual Workstation will run on general 475 PCs as well. See <file:Documentation/sgi-visws.txt> for details. 476 477config X86_SUMMIT 478 bool "Summit/EXA (IBM x440)" 479 depends on X86_32_NON_STANDARD 480 ---help--- 481 This option is needed for IBM systems that use the Summit/EXA chipset. 482 In particular, it is needed for the x440. 483 484config X86_ES7000 485 bool "Unisys ES7000 IA32 series" 486 depends on X86_32_NON_STANDARD && X86_BIGSMP 487 ---help--- 488 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is 489 supposed to run on an IA32-based Unisys ES7000 system. 490 491config SCHED_OMIT_FRAME_POINTER 492 def_bool y 493 prompt "Single-depth WCHAN output" 494 depends on X86 495 ---help--- 496 Calculate simpler /proc/<PID>/wchan values. If this option 497 is disabled then wchan values will recurse back to the 498 caller function. This provides more accurate wchan values, 499 at the expense of slightly more scheduling overhead. 500 501 If in doubt, say "Y". 502 503menuconfig PARAVIRT_GUEST 504 bool "Paravirtualized guest support" 505 ---help--- 506 Say Y here to get to see options related to running Linux under 507 various hypervisors. This option alone does not add any kernel code. 508 509 If you say N, all options in this submenu will be skipped and disabled. 510 511if PARAVIRT_GUEST 512 513source "arch/x86/xen/Kconfig" 514 515config VMI 516 bool "VMI Guest support (DEPRECATED)" 517 select PARAVIRT 518 depends on X86_32 519 ---help--- 520 VMI provides a paravirtualized interface to the VMware ESX server 521 (it could be used by other hypervisors in theory too, but is not 522 at the moment), by linking the kernel to a GPL-ed ROM module 523 provided by the hypervisor. 524 525 As of September 2009, VMware has started a phased retirement 526 of this feature from VMware's products. Please see 527 feature-removal-schedule.txt for details. If you are 528 planning to enable this option, please note that you cannot 529 live migrate a VMI enabled VM to a future VMware product, 530 which doesn't support VMI. So if you expect your kernel to 531 seamlessly migrate to newer VMware products, keep this 532 disabled. 533 534config KVM_CLOCK 535 bool "KVM paravirtualized clock" 536 select PARAVIRT 537 select PARAVIRT_CLOCK 538 ---help--- 539 Turning on this option will allow you to run a paravirtualized clock 540 when running over the KVM hypervisor. Instead of relying on a PIT 541 (or probably other) emulation by the underlying device model, the host 542 provides the guest with timing infrastructure such as time of day, and 543 system time 544 545config KVM_GUEST 546 bool "KVM Guest support" 547 select PARAVIRT 548 ---help--- 549 This option enables various optimizations for running under the KVM 550 hypervisor. 551 552source "arch/x86/lguest/Kconfig" 553 554config PARAVIRT 555 bool "Enable paravirtualization code" 556 ---help--- 557 This changes the kernel so it can modify itself when it is run 558 under a hypervisor, potentially improving performance significantly 559 over full virtualization. However, when run without a hypervisor 560 the kernel is theoretically slower and slightly larger. 561 562config PARAVIRT_SPINLOCKS 563 bool "Paravirtualization layer for spinlocks" 564 depends on PARAVIRT && SMP && EXPERIMENTAL 565 ---help--- 566 Paravirtualized spinlocks allow a pvops backend to replace the 567 spinlock implementation with something virtualization-friendly 568 (for example, block the virtual CPU rather than spinning). 569 570 Unfortunately the downside is an up to 5% performance hit on 571 native kernels, with various workloads. 572 573 If you are unsure how to answer this question, answer N. 574 575config PARAVIRT_CLOCK 576 bool 577 578endif 579 580config PARAVIRT_DEBUG 581 bool "paravirt-ops debugging" 582 depends on PARAVIRT && DEBUG_KERNEL 583 ---help--- 584 Enable to debug paravirt_ops internals. Specifically, BUG if 585 a paravirt_op is missing when it is called. 586 587config NO_BOOTMEM 588 default y 589 bool "Disable Bootmem code" 590 ---help--- 591 Use early_res directly instead of bootmem before slab is ready. 592 - allocator (buddy) [generic] 593 - early allocator (bootmem) [generic] 594 - very early allocator (reserve_early*()) [x86] 595 - very very early allocator (early brk model) [x86] 596 So reduce one layer between early allocator to final allocator 597 598 599config MEMTEST 600 bool "Memtest" 601 ---help--- 602 This option adds a kernel parameter 'memtest', which allows memtest 603 to be set. 604 memtest=0, mean disabled; -- default 605 memtest=1, mean do 1 test pattern; 606 ... 607 memtest=4, mean do 4 test patterns. 608 If you are unsure how to answer this question, answer N. 609 610config X86_SUMMIT_NUMA 611 def_bool y 612 depends on X86_32 && NUMA && X86_32_NON_STANDARD 613 614config X86_CYCLONE_TIMER 615 def_bool y 616 depends on X86_32_NON_STANDARD 617 618source "arch/x86/Kconfig.cpu" 619 620config HPET_TIMER 621 def_bool X86_64 622 prompt "HPET Timer Support" if X86_32 623 ---help--- 624 Use the IA-PC HPET (High Precision Event Timer) to manage 625 time in preference to the PIT and RTC, if a HPET is 626 present. 627 HPET is the next generation timer replacing legacy 8254s. 628 The HPET provides a stable time base on SMP 629 systems, unlike the TSC, but it is more expensive to access, 630 as it is off-chip. You can find the HPET spec at 631 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>. 632 633 You can safely choose Y here. However, HPET will only be 634 activated if the platform and the BIOS support this feature. 635 Otherwise the 8254 will be used for timing services. 636 637 Choose N to continue using the legacy 8254 timer. 638 639config HPET_EMULATE_RTC 640 def_bool y 641 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 642 643config APB_TIMER 644 def_bool y if MRST 645 prompt "Langwell APB Timer Support" if X86_MRST 646 help 647 APB timer is the replacement for 8254, HPET on X86 MID platforms. 648 The APBT provides a stable time base on SMP 649 systems, unlike the TSC, but it is more expensive to access, 650 as it is off-chip. APB timers are always running regardless of CPU 651 C states, they are used as per CPU clockevent device when possible. 652 653# Mark as embedded because too many people got it wrong. 654# The code disables itself when not needed. 655config DMI 656 default y 657 bool "Enable DMI scanning" if EMBEDDED 658 ---help--- 659 Enabled scanning of DMI to identify machine quirks. Say Y 660 here unless you have verified that your setup is not 661 affected by entries in the DMI blacklist. Required by PNP 662 BIOS code. 663 664config GART_IOMMU 665 bool "GART IOMMU support" if EMBEDDED 666 default y 667 select SWIOTLB 668 depends on X86_64 && PCI && K8_NB 669 ---help--- 670 Support for full DMA access of devices with 32bit memory access only 671 on systems with more than 3GB. This is usually needed for USB, 672 sound, many IDE/SATA chipsets and some other devices. 673 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART 674 based hardware IOMMU and a software bounce buffer based IOMMU used 675 on Intel systems and as fallback. 676 The code is only active when needed (enough memory and limited 677 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified 678 too. 679 680config CALGARY_IOMMU 681 bool "IBM Calgary IOMMU support" 682 select SWIOTLB 683 depends on X86_64 && PCI && EXPERIMENTAL 684 ---help--- 685 Support for hardware IOMMUs in IBM's xSeries x366 and x460 686 systems. Needed to run systems with more than 3GB of memory 687 properly with 32-bit PCI devices that do not support DAC 688 (Double Address Cycle). Calgary also supports bus level 689 isolation, where all DMAs pass through the IOMMU. This 690 prevents them from going anywhere except their intended 691 destination. This catches hard-to-find kernel bugs and 692 mis-behaving drivers and devices that do not use the DMA-API 693 properly to set up their DMA buffers. The IOMMU can be 694 turned off at boot time with the iommu=off parameter. 695 Normally the kernel will make the right choice by itself. 696 If unsure, say Y. 697 698config CALGARY_IOMMU_ENABLED_BY_DEFAULT 699 def_bool y 700 prompt "Should Calgary be enabled by default?" 701 depends on CALGARY_IOMMU 702 ---help--- 703 Should Calgary be enabled by default? if you choose 'y', Calgary 704 will be used (if it exists). If you choose 'n', Calgary will not be 705 used even if it exists. If you choose 'n' and would like to use 706 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 707 If unsure, say Y. 708 709config AMD_IOMMU 710 bool "AMD IOMMU support" 711 select SWIOTLB 712 select PCI_MSI 713 depends on X86_64 && PCI && ACPI 714 ---help--- 715 With this option you can enable support for AMD IOMMU hardware in 716 your system. An IOMMU is a hardware component which provides 717 remapping of DMA memory accesses from devices. With an AMD IOMMU you 718 can isolate the the DMA memory of different devices and protect the 719 system from misbehaving device drivers or hardware. 720 721 You can find out if your system has an AMD IOMMU if you look into 722 your BIOS for an option to enable it or if you have an IVRS ACPI 723 table. 724 725config AMD_IOMMU_STATS 726 bool "Export AMD IOMMU statistics to debugfs" 727 depends on AMD_IOMMU 728 select DEBUG_FS 729 ---help--- 730 This option enables code in the AMD IOMMU driver to collect various 731 statistics about whats happening in the driver and exports that 732 information to userspace via debugfs. 733 If unsure, say N. 734 735# need this always selected by IOMMU for the VIA workaround 736config SWIOTLB 737 def_bool y if X86_64 738 ---help--- 739 Support for software bounce buffers used on x86-64 systems 740 which don't have a hardware IOMMU (e.g. the current generation 741 of Intel's x86-64 CPUs). Using this PCI devices which can only 742 access 32-bits of memory can be used on systems with more than 743 3 GB of memory. If unsure, say Y. 744 745config IOMMU_HELPER 746 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU) 747 748config IOMMU_API 749 def_bool (AMD_IOMMU || DMAR) 750 751config MAXSMP 752 bool "Configure Maximum number of SMP Processors and NUMA Nodes" 753 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL 754 select CPUMASK_OFFSTACK 755 ---help--- 756 Configure maximum number of CPUS and NUMA Nodes for this architecture. 757 If unsure, say N. 758 759config NR_CPUS 760 int "Maximum number of CPUs" if SMP && !MAXSMP 761 range 2 8 if SMP && X86_32 && !X86_BIGSMP 762 range 2 512 if SMP && !MAXSMP 763 default "1" if !SMP 764 default "4096" if MAXSMP 765 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000) 766 default "8" if SMP 767 ---help--- 768 This allows you to specify the maximum number of CPUs which this 769 kernel will support. The maximum supported value is 512 and the 770 minimum value which makes sense is 2. 771 772 This is purely to save memory - each supported CPU adds 773 approximately eight kilobytes to the kernel image. 774 775config SCHED_SMT 776 bool "SMT (Hyperthreading) scheduler support" 777 depends on X86_HT 778 ---help--- 779 SMT scheduler support improves the CPU scheduler's decision making 780 when dealing with Intel Pentium 4 chips with HyperThreading at a 781 cost of slightly increased overhead in some places. If unsure say 782 N here. 783 784config SCHED_MC 785 def_bool y 786 prompt "Multi-core scheduler support" 787 depends on X86_HT 788 ---help--- 789 Multi-core scheduler support improves the CPU scheduler's decision 790 making when dealing with multi-core CPU chips at a cost of slightly 791 increased overhead in some places. If unsure say N here. 792 793source "kernel/Kconfig.preempt" 794 795config X86_UP_APIC 796 bool "Local APIC support on uniprocessors" 797 depends on X86_32 && !SMP && !X86_32_NON_STANDARD 798 ---help--- 799 A local APIC (Advanced Programmable Interrupt Controller) is an 800 integrated interrupt controller in the CPU. If you have a single-CPU 801 system which has a processor with a local APIC, you can say Y here to 802 enable and use it. If you say Y here even though your machine doesn't 803 have a local APIC, then the kernel will still run with no slowdown at 804 all. The local APIC supports CPU-generated self-interrupts (timer, 805 performance counters), and the NMI watchdog which detects hard 806 lockups. 807 808config X86_UP_IOAPIC 809 bool "IO-APIC support on uniprocessors" 810 depends on X86_UP_APIC 811 ---help--- 812 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 813 SMP-capable replacement for PC-style interrupt controllers. Most 814 SMP systems and many recent uniprocessor systems have one. 815 816 If you have a single-CPU system with an IO-APIC, you can say Y here 817 to use it. If you say Y here even though your machine doesn't have 818 an IO-APIC, then the kernel will still run with no slowdown at all. 819 820config X86_LOCAL_APIC 821 def_bool y 822 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC 823 824config X86_IO_APIC 825 def_bool y 826 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC 827 828config X86_VISWS_APIC 829 def_bool y 830 depends on X86_32 && X86_VISWS 831 832config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 833 bool "Reroute for broken boot IRQs" 834 depends on X86_IO_APIC 835 ---help--- 836 This option enables a workaround that fixes a source of 837 spurious interrupts. This is recommended when threaded 838 interrupt handling is used on systems where the generation of 839 superfluous "boot interrupts" cannot be disabled. 840 841 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 842 entry in the chipset's IO-APIC is masked (as, e.g. the RT 843 kernel does during interrupt handling). On chipsets where this 844 boot IRQ generation cannot be disabled, this workaround keeps 845 the original IRQ line masked so that only the equivalent "boot 846 IRQ" is delivered to the CPUs. The workaround also tells the 847 kernel to set up the IRQ handler on the boot IRQ line. In this 848 way only one interrupt is delivered to the kernel. Otherwise 849 the spurious second interrupt may cause the kernel to bring 850 down (vital) interrupt lines. 851 852 Only affects "broken" chipsets. Interrupt sharing may be 853 increased on these systems. 854 855config X86_MCE 856 bool "Machine Check / overheating reporting" 857 ---help--- 858 Machine Check support allows the processor to notify the 859 kernel if it detects a problem (e.g. overheating, data corruption). 860 The action the kernel takes depends on the severity of the problem, 861 ranging from warning messages to halting the machine. 862 863config X86_MCE_INTEL 864 def_bool y 865 prompt "Intel MCE features" 866 depends on X86_MCE && X86_LOCAL_APIC 867 ---help--- 868 Additional support for intel specific MCE features such as 869 the thermal monitor. 870 871config X86_MCE_AMD 872 def_bool y 873 prompt "AMD MCE features" 874 depends on X86_MCE && X86_LOCAL_APIC 875 ---help--- 876 Additional support for AMD specific MCE features such as 877 the DRAM Error Threshold. 878 879config X86_ANCIENT_MCE 880 bool "Support for old Pentium 5 / WinChip machine checks" 881 depends on X86_32 && X86_MCE 882 ---help--- 883 Include support for machine check handling on old Pentium 5 or WinChip 884 systems. These typically need to be enabled explicitely on the command 885 line. 886 887config X86_MCE_THRESHOLD 888 depends on X86_MCE_AMD || X86_MCE_INTEL 889 def_bool y 890 891config X86_MCE_INJECT 892 depends on X86_MCE 893 tristate "Machine check injector support" 894 ---help--- 895 Provide support for injecting machine checks for testing purposes. 896 If you don't know what a machine check is and you don't do kernel 897 QA it is safe to say n. 898 899config X86_THERMAL_VECTOR 900 def_bool y 901 depends on X86_MCE_INTEL 902 903config VM86 904 bool "Enable VM86 support" if EMBEDDED 905 default y 906 depends on X86_32 907 ---help--- 908 This option is required by programs like DOSEMU to run 16-bit legacy 909 code on X86 processors. It also may be needed by software like 910 XFree86 to initialize some video cards via BIOS. Disabling this 911 option saves about 6k. 912 913config TOSHIBA 914 tristate "Toshiba Laptop support" 915 depends on X86_32 916 ---help--- 917 This adds a driver to safely access the System Management Mode of 918 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 919 not work on models with a Phoenix BIOS. The System Management Mode 920 is used to set the BIOS and power saving options on Toshiba portables. 921 922 For information on utilities to make use of this driver see the 923 Toshiba Linux utilities web site at: 924 <http://www.buzzard.org.uk/toshiba/>. 925 926 Say Y if you intend to run this kernel on a Toshiba portable. 927 Say N otherwise. 928 929config I8K 930 tristate "Dell laptop support" 931 ---help--- 932 This adds a driver to safely access the System Management Mode 933 of the CPU on the Dell Inspiron 8000. The System Management Mode 934 is used to read cpu temperature and cooling fan status and to 935 control the fans on the I8K portables. 936 937 This driver has been tested only on the Inspiron 8000 but it may 938 also work with other Dell laptops. You can force loading on other 939 models by passing the parameter `force=1' to the module. Use at 940 your own risk. 941 942 For information on utilities to make use of this driver see the 943 I8K Linux utilities web site at: 944 <http://people.debian.org/~dz/i8k/> 945 946 Say Y if you intend to run this kernel on a Dell Inspiron 8000. 947 Say N otherwise. 948 949config X86_REBOOTFIXUPS 950 bool "Enable X86 board specific fixups for reboot" 951 depends on X86_32 952 ---help--- 953 This enables chipset and/or board specific fixups to be done 954 in order to get reboot to work correctly. This is only needed on 955 some combinations of hardware and BIOS. The symptom, for which 956 this config is intended, is when reboot ends with a stalled/hung 957 system. 958 959 Currently, the only fixup is for the Geode machines using 960 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 961 962 Say Y if you want to enable the fixup. Currently, it's safe to 963 enable this option even if you don't need it. 964 Say N otherwise. 965 966config MICROCODE 967 tristate "/dev/cpu/microcode - microcode support" 968 select FW_LOADER 969 ---help--- 970 If you say Y here, you will be able to update the microcode on 971 certain Intel and AMD processors. The Intel support is for the 972 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, 973 Pentium 4, Xeon etc. The AMD support is for family 0x10 and 974 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra. 975 You will obviously need the actual microcode binary data itself 976 which is not shipped with the Linux kernel. 977 978 This option selects the general module only, you need to select 979 at least one vendor specific module as well. 980 981 To compile this driver as a module, choose M here: the 982 module will be called microcode. 983 984config MICROCODE_INTEL 985 bool "Intel microcode patch loading support" 986 depends on MICROCODE 987 default MICROCODE 988 select FW_LOADER 989 ---help--- 990 This options enables microcode patch loading support for Intel 991 processors. 992 993 For latest news and information on obtaining all the required 994 Intel ingredients for this driver, check: 995 <http://www.urbanmyth.org/microcode/>. 996 997config MICROCODE_AMD 998 bool "AMD microcode patch loading support" 999 depends on MICROCODE 1000 select FW_LOADER 1001 ---help--- 1002 If you select this option, microcode patch loading support for AMD 1003 processors will be enabled. 1004 1005config MICROCODE_OLD_INTERFACE 1006 def_bool y 1007 depends on MICROCODE 1008 1009config X86_MSR 1010 tristate "/dev/cpu/*/msr - Model-specific register support" 1011 ---help--- 1012 This device gives privileged processes access to the x86 1013 Model-Specific Registers (MSRs). It is a character device with 1014 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1015 MSR accesses are directed to a specific CPU on multi-processor 1016 systems. 1017 1018config X86_CPUID 1019 tristate "/dev/cpu/*/cpuid - CPU information support" 1020 ---help--- 1021 This device gives processes access to the x86 CPUID instruction to 1022 be executed on a specific processor. It is a character device 1023 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1024 /dev/cpu/31/cpuid. 1025 1026choice 1027 prompt "High Memory Support" 1028 default HIGHMEM64G if X86_NUMAQ 1029 default HIGHMEM4G 1030 depends on X86_32 1031 1032config NOHIGHMEM 1033 bool "off" 1034 depends on !X86_NUMAQ 1035 ---help--- 1036 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1037 However, the address space of 32-bit x86 processors is only 4 1038 Gigabytes large. That means that, if you have a large amount of 1039 physical memory, not all of it can be "permanently mapped" by the 1040 kernel. The physical memory that's not permanently mapped is called 1041 "high memory". 1042 1043 If you are compiling a kernel which will never run on a machine with 1044 more than 1 Gigabyte total physical RAM, answer "off" here (default 1045 choice and suitable for most users). This will result in a "3GB/1GB" 1046 split: 3GB are mapped so that each process sees a 3GB virtual memory 1047 space and the remaining part of the 4GB virtual memory space is used 1048 by the kernel to permanently map as much physical memory as 1049 possible. 1050 1051 If the machine has between 1 and 4 Gigabytes physical RAM, then 1052 answer "4GB" here. 1053 1054 If more than 4 Gigabytes is used then answer "64GB" here. This 1055 selection turns Intel PAE (Physical Address Extension) mode on. 1056 PAE implements 3-level paging on IA32 processors. PAE is fully 1057 supported by Linux, PAE mode is implemented on all recent Intel 1058 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1059 then the kernel will not boot on CPUs that don't support PAE! 1060 1061 The actual amount of total physical memory will either be 1062 auto detected or can be forced by using a kernel command line option 1063 such as "mem=256M". (Try "man bootparam" or see the documentation of 1064 your boot loader (lilo or loadlin) about how to pass options to the 1065 kernel at boot time.) 1066 1067 If unsure, say "off". 1068 1069config HIGHMEM4G 1070 bool "4GB" 1071 depends on !X86_NUMAQ 1072 ---help--- 1073 Select this if you have a 32-bit processor and between 1 and 4 1074 gigabytes of physical RAM. 1075 1076config HIGHMEM64G 1077 bool "64GB" 1078 depends on !M386 && !M486 1079 select X86_PAE 1080 ---help--- 1081 Select this if you have a 32-bit processor and more than 4 1082 gigabytes of physical RAM. 1083 1084endchoice 1085 1086choice 1087 depends on EXPERIMENTAL 1088 prompt "Memory split" if EMBEDDED 1089 default VMSPLIT_3G 1090 depends on X86_32 1091 ---help--- 1092 Select the desired split between kernel and user memory. 1093 1094 If the address range available to the kernel is less than the 1095 physical memory installed, the remaining memory will be available 1096 as "high memory". Accessing high memory is a little more costly 1097 than low memory, as it needs to be mapped into the kernel first. 1098 Note that increasing the kernel address space limits the range 1099 available to user programs, making the address space there 1100 tighter. Selecting anything other than the default 3G/1G split 1101 will also likely make your kernel incompatible with binary-only 1102 kernel modules. 1103 1104 If you are not absolutely sure what you are doing, leave this 1105 option alone! 1106 1107 config VMSPLIT_3G 1108 bool "3G/1G user/kernel split" 1109 config VMSPLIT_3G_OPT 1110 depends on !X86_PAE 1111 bool "3G/1G user/kernel split (for full 1G low memory)" 1112 config VMSPLIT_2G 1113 bool "2G/2G user/kernel split" 1114 config VMSPLIT_2G_OPT 1115 depends on !X86_PAE 1116 bool "2G/2G user/kernel split (for full 2G low memory)" 1117 config VMSPLIT_1G 1118 bool "1G/3G user/kernel split" 1119endchoice 1120 1121config PAGE_OFFSET 1122 hex 1123 default 0xB0000000 if VMSPLIT_3G_OPT 1124 default 0x80000000 if VMSPLIT_2G 1125 default 0x78000000 if VMSPLIT_2G_OPT 1126 default 0x40000000 if VMSPLIT_1G 1127 default 0xC0000000 1128 depends on X86_32 1129 1130config HIGHMEM 1131 def_bool y 1132 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1133 1134config X86_PAE 1135 bool "PAE (Physical Address Extension) Support" 1136 depends on X86_32 && !HIGHMEM4G 1137 ---help--- 1138 PAE is required for NX support, and furthermore enables 1139 larger swapspace support for non-overcommit purposes. It 1140 has the cost of more pagetable lookup overhead, and also 1141 consumes more pagetable space per process. 1142 1143config ARCH_PHYS_ADDR_T_64BIT 1144 def_bool X86_64 || X86_PAE 1145 1146config DIRECT_GBPAGES 1147 bool "Enable 1GB pages for kernel pagetables" if EMBEDDED 1148 default y 1149 depends on X86_64 1150 ---help--- 1151 Allow the kernel linear mapping to use 1GB pages on CPUs that 1152 support it. This can improve the kernel's performance a tiny bit by 1153 reducing TLB pressure. If in doubt, say "Y". 1154 1155# Common NUMA Features 1156config NUMA 1157 bool "Numa Memory Allocation and Scheduler Support" 1158 depends on SMP 1159 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL) 1160 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP) 1161 ---help--- 1162 Enable NUMA (Non Uniform Memory Access) support. 1163 1164 The kernel will try to allocate memory used by a CPU on the 1165 local memory controller of the CPU and add some more 1166 NUMA awareness to the kernel. 1167 1168 For 64-bit this is recommended if the system is Intel Core i7 1169 (or later), AMD Opteron, or EM64T NUMA. 1170 1171 For 32-bit this is only needed on (rare) 32-bit-only platforms 1172 that support NUMA topologies, such as NUMAQ / Summit, or if you 1173 boot a 32-bit kernel on a 64-bit NUMA platform. 1174 1175 Otherwise, you should say N. 1176 1177comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI" 1178 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI) 1179 1180config K8_NUMA 1181 def_bool y 1182 prompt "Old style AMD Opteron NUMA detection" 1183 depends on X86_64 && NUMA && PCI 1184 ---help--- 1185 Enable K8 NUMA node topology detection. You should say Y here if 1186 you have a multi processor AMD K8 system. This uses an old 1187 method to read the NUMA configuration directly from the builtin 1188 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA 1189 instead, which also takes priority if both are compiled in. 1190 1191config X86_64_ACPI_NUMA 1192 def_bool y 1193 prompt "ACPI NUMA detection" 1194 depends on X86_64 && NUMA && ACPI && PCI 1195 select ACPI_NUMA 1196 ---help--- 1197 Enable ACPI SRAT based node topology detection. 1198 1199# Some NUMA nodes have memory ranges that span 1200# other nodes. Even though a pfn is valid and 1201# between a node's start and end pfns, it may not 1202# reside on that node. See memmap_init_zone() 1203# for details. 1204config NODES_SPAN_OTHER_NODES 1205 def_bool y 1206 depends on X86_64_ACPI_NUMA 1207 1208config NUMA_EMU 1209 bool "NUMA emulation" 1210 depends on X86_64 && NUMA 1211 ---help--- 1212 Enable NUMA emulation. A flat machine will be split 1213 into virtual nodes when booted with "numa=fake=N", where N is the 1214 number of nodes. This is only useful for debugging. 1215 1216config NODES_SHIFT 1217 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1218 range 1 10 1219 default "10" if MAXSMP 1220 default "6" if X86_64 1221 default "4" if X86_NUMAQ 1222 default "3" 1223 depends on NEED_MULTIPLE_NODES 1224 ---help--- 1225 Specify the maximum number of NUMA Nodes available on the target 1226 system. Increases memory reserved to accommodate various tables. 1227 1228config HAVE_ARCH_BOOTMEM 1229 def_bool y 1230 depends on X86_32 && NUMA 1231 1232config ARCH_HAVE_MEMORY_PRESENT 1233 def_bool y 1234 depends on X86_32 && DISCONTIGMEM 1235 1236config NEED_NODE_MEMMAP_SIZE 1237 def_bool y 1238 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1239 1240config HAVE_ARCH_ALLOC_REMAP 1241 def_bool y 1242 depends on X86_32 && NUMA 1243 1244config ARCH_FLATMEM_ENABLE 1245 def_bool y 1246 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA 1247 1248config ARCH_DISCONTIGMEM_ENABLE 1249 def_bool y 1250 depends on NUMA && X86_32 1251 1252config ARCH_DISCONTIGMEM_DEFAULT 1253 def_bool y 1254 depends on NUMA && X86_32 1255 1256config ARCH_PROC_KCORE_TEXT 1257 def_bool y 1258 depends on X86_64 && PROC_KCORE 1259 1260config ARCH_SPARSEMEM_DEFAULT 1261 def_bool y 1262 depends on X86_64 1263 1264config ARCH_SPARSEMEM_ENABLE 1265 def_bool y 1266 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD 1267 select SPARSEMEM_STATIC if X86_32 1268 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1269 1270config ARCH_SELECT_MEMORY_MODEL 1271 def_bool y 1272 depends on ARCH_SPARSEMEM_ENABLE 1273 1274config ARCH_MEMORY_PROBE 1275 def_bool X86_64 1276 depends on MEMORY_HOTPLUG 1277 1278config ILLEGAL_POINTER_VALUE 1279 hex 1280 default 0 if X86_32 1281 default 0xdead000000000000 if X86_64 1282 1283source "mm/Kconfig" 1284 1285config HIGHPTE 1286 bool "Allocate 3rd-level pagetables from highmem" 1287 depends on HIGHMEM 1288 ---help--- 1289 The VM uses one page table entry for each page of physical memory. 1290 For systems with a lot of RAM, this can be wasteful of precious 1291 low memory. Setting this option will put user-space page table 1292 entries in high memory. 1293 1294config X86_CHECK_BIOS_CORRUPTION 1295 bool "Check for low memory corruption" 1296 ---help--- 1297 Periodically check for memory corruption in low memory, which 1298 is suspected to be caused by BIOS. Even when enabled in the 1299 configuration, it is disabled at runtime. Enable it by 1300 setting "memory_corruption_check=1" on the kernel command 1301 line. By default it scans the low 64k of memory every 60 1302 seconds; see the memory_corruption_check_size and 1303 memory_corruption_check_period parameters in 1304 Documentation/kernel-parameters.txt to adjust this. 1305 1306 When enabled with the default parameters, this option has 1307 almost no overhead, as it reserves a relatively small amount 1308 of memory and scans it infrequently. It both detects corruption 1309 and prevents it from affecting the running system. 1310 1311 It is, however, intended as a diagnostic tool; if repeatable 1312 BIOS-originated corruption always affects the same memory, 1313 you can use memmap= to prevent the kernel from using that 1314 memory. 1315 1316config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1317 bool "Set the default setting of memory_corruption_check" 1318 depends on X86_CHECK_BIOS_CORRUPTION 1319 default y 1320 ---help--- 1321 Set whether the default state of memory_corruption_check is 1322 on or off. 1323 1324config X86_RESERVE_LOW_64K 1325 bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen" 1326 default y 1327 ---help--- 1328 Reserve the first 64K of physical RAM on BIOSes that are known 1329 to potentially corrupt that memory range. A numbers of BIOSes are 1330 known to utilize this area during suspend/resume, so it must not 1331 be used by the kernel. 1332 1333 Set this to N if you are absolutely sure that you trust the BIOS 1334 to get all its memory reservations and usages right. 1335 1336 If you have doubts about the BIOS (e.g. suspend/resume does not 1337 work or there's kernel crashes after certain hardware hotplug 1338 events) and it's not AMI or Phoenix, then you might want to enable 1339 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical 1340 corruption patterns. 1341 1342 Say Y if unsure. 1343 1344config MATH_EMULATION 1345 bool 1346 prompt "Math emulation" if X86_32 1347 ---help--- 1348 Linux can emulate a math coprocessor (used for floating point 1349 operations) if you don't have one. 486DX and Pentium processors have 1350 a math coprocessor built in, 486SX and 386 do not, unless you added 1351 a 487DX or 387, respectively. (The messages during boot time can 1352 give you some hints here ["man dmesg"].) Everyone needs either a 1353 coprocessor or this emulation. 1354 1355 If you don't have a math coprocessor, you need to say Y here; if you 1356 say Y here even though you have a coprocessor, the coprocessor will 1357 be used nevertheless. (This behavior can be changed with the kernel 1358 command line option "no387", which comes handy if your coprocessor 1359 is broken. Try "man bootparam" or see the documentation of your boot 1360 loader (lilo or loadlin) about how to pass options to the kernel at 1361 boot time.) This means that it is a good idea to say Y here if you 1362 intend to use this kernel on different machines. 1363 1364 More information about the internals of the Linux math coprocessor 1365 emulation can be found in <file:arch/x86/math-emu/README>. 1366 1367 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1368 kernel, it won't hurt. 1369 1370config MTRR 1371 def_bool y 1372 prompt "MTRR (Memory Type Range Register) support" if EMBEDDED 1373 ---help--- 1374 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1375 the Memory Type Range Registers (MTRRs) may be used to control 1376 processor access to memory ranges. This is most useful if you have 1377 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1378 allows bus write transfers to be combined into a larger transfer 1379 before bursting over the PCI/AGP bus. This can increase performance 1380 of image write operations 2.5 times or more. Saying Y here creates a 1381 /proc/mtrr file which may be used to manipulate your processor's 1382 MTRRs. Typically the X server should use this. 1383 1384 This code has a reasonably generic interface so that similar 1385 control registers on other processors can be easily supported 1386 as well: 1387 1388 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1389 Registers (ARRs) which provide a similar functionality to MTRRs. For 1390 these, the ARRs are used to emulate the MTRRs. 1391 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1392 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1393 write-combining. All of these processors are supported by this code 1394 and it makes sense to say Y here if you have one of them. 1395 1396 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1397 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1398 can lead to all sorts of problems, so it's good to say Y here. 1399 1400 You can safely say Y even if your machine doesn't have MTRRs, you'll 1401 just add about 9 KB to your kernel. 1402 1403 See <file:Documentation/x86/mtrr.txt> for more information. 1404 1405config MTRR_SANITIZER 1406 def_bool y 1407 prompt "MTRR cleanup support" 1408 depends on MTRR 1409 ---help--- 1410 Convert MTRR layout from continuous to discrete, so X drivers can 1411 add writeback entries. 1412 1413 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1414 The largest mtrr entry size for a continuous block can be set with 1415 mtrr_chunk_size. 1416 1417 If unsure, say Y. 1418 1419config MTRR_SANITIZER_ENABLE_DEFAULT 1420 int "MTRR cleanup enable value (0-1)" 1421 range 0 1 1422 default "0" 1423 depends on MTRR_SANITIZER 1424 ---help--- 1425 Enable mtrr cleanup default value 1426 1427config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1428 int "MTRR cleanup spare reg num (0-7)" 1429 range 0 7 1430 default "1" 1431 depends on MTRR_SANITIZER 1432 ---help--- 1433 mtrr cleanup spare entries default, it can be changed via 1434 mtrr_spare_reg_nr=N on the kernel command line. 1435 1436config X86_PAT 1437 def_bool y 1438 prompt "x86 PAT support" if EMBEDDED 1439 depends on MTRR 1440 ---help--- 1441 Use PAT attributes to setup page level cache control. 1442 1443 PATs are the modern equivalents of MTRRs and are much more 1444 flexible than MTRRs. 1445 1446 Say N here if you see bootup problems (boot crash, boot hang, 1447 spontaneous reboots) or a non-working video driver. 1448 1449 If unsure, say Y. 1450 1451config ARCH_USES_PG_UNCACHED 1452 def_bool y 1453 depends on X86_PAT 1454 1455config EFI 1456 bool "EFI runtime service support" 1457 depends on ACPI 1458 ---help--- 1459 This enables the kernel to use EFI runtime services that are 1460 available (such as the EFI variable services). 1461 1462 This option is only useful on systems that have EFI firmware. 1463 In addition, you should use the latest ELILO loader available 1464 at <http://elilo.sourceforge.net> in order to take advantage 1465 of EFI runtime services. However, even with this option, the 1466 resultant kernel should continue to boot on existing non-EFI 1467 platforms. 1468 1469config SECCOMP 1470 def_bool y 1471 prompt "Enable seccomp to safely compute untrusted bytecode" 1472 ---help--- 1473 This kernel feature is useful for number crunching applications 1474 that may need to compute untrusted bytecode during their 1475 execution. By using pipes or other transports made available to 1476 the process as file descriptors supporting the read/write 1477 syscalls, it's possible to isolate those applications in 1478 their own address space using seccomp. Once seccomp is 1479 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1480 and the task is only allowed to execute a few safe syscalls 1481 defined by each seccomp mode. 1482 1483 If unsure, say Y. Only embedded should say N here. 1484 1485config CC_STACKPROTECTOR 1486 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)" 1487 ---help--- 1488 This option turns on the -fstack-protector GCC feature. This 1489 feature puts, at the beginning of functions, a canary value on 1490 the stack just before the return address, and validates 1491 the value just before actually returning. Stack based buffer 1492 overflows (that need to overwrite this return address) now also 1493 overwrite the canary, which gets detected and the attack is then 1494 neutralized via a kernel panic. 1495 1496 This feature requires gcc version 4.2 or above, or a distribution 1497 gcc with the feature backported. Older versions are automatically 1498 detected and for those versions, this configuration option is 1499 ignored. (and a warning is printed during bootup) 1500 1501source kernel/Kconfig.hz 1502 1503config KEXEC 1504 bool "kexec system call" 1505 ---help--- 1506 kexec is a system call that implements the ability to shutdown your 1507 current kernel, and to start another kernel. It is like a reboot 1508 but it is independent of the system firmware. And like a reboot 1509 you can start any kernel with it, not just Linux. 1510 1511 The name comes from the similarity to the exec system call. 1512 1513 It is an ongoing process to be certain the hardware in a machine 1514 is properly shutdown, so do not be surprised if this code does not 1515 initially work for you. It may help to enable device hotplugging 1516 support. As of this writing the exact hardware interface is 1517 strongly in flux, so no good recommendation can be made. 1518 1519config CRASH_DUMP 1520 bool "kernel crash dumps" 1521 depends on X86_64 || (X86_32 && HIGHMEM) 1522 ---help--- 1523 Generate crash dump after being started by kexec. 1524 This should be normally only set in special crash dump kernels 1525 which are loaded in the main kernel with kexec-tools into 1526 a specially reserved region and then later executed after 1527 a crash by kdump/kexec. The crash dump kernel must be compiled 1528 to a memory address not used by the main kernel or BIOS using 1529 PHYSICAL_START, or it must be built as a relocatable image 1530 (CONFIG_RELOCATABLE=y). 1531 For more details see Documentation/kdump/kdump.txt 1532 1533config KEXEC_JUMP 1534 bool "kexec jump (EXPERIMENTAL)" 1535 depends on EXPERIMENTAL 1536 depends on KEXEC && HIBERNATION 1537 ---help--- 1538 Jump between original kernel and kexeced kernel and invoke 1539 code in physical address mode via KEXEC 1540 1541config PHYSICAL_START 1542 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP) 1543 default "0x1000000" 1544 ---help--- 1545 This gives the physical address where the kernel is loaded. 1546 1547 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1548 bzImage will decompress itself to above physical address and 1549 run from there. Otherwise, bzImage will run from the address where 1550 it has been loaded by the boot loader and will ignore above physical 1551 address. 1552 1553 In normal kdump cases one does not have to set/change this option 1554 as now bzImage can be compiled as a completely relocatable image 1555 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1556 address. This option is mainly useful for the folks who don't want 1557 to use a bzImage for capturing the crash dump and want to use a 1558 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1559 to be specifically compiled to run from a specific memory area 1560 (normally a reserved region) and this option comes handy. 1561 1562 So if you are using bzImage for capturing the crash dump, 1563 leave the value here unchanged to 0x1000000 and set 1564 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1565 for capturing the crash dump change this value to start of 1566 the reserved region. In other words, it can be set based on 1567 the "X" value as specified in the "crashkernel=YM@XM" 1568 command line boot parameter passed to the panic-ed 1569 kernel. Please take a look at Documentation/kdump/kdump.txt 1570 for more details about crash dumps. 1571 1572 Usage of bzImage for capturing the crash dump is recommended as 1573 one does not have to build two kernels. Same kernel can be used 1574 as production kernel and capture kernel. Above option should have 1575 gone away after relocatable bzImage support is introduced. But it 1576 is present because there are users out there who continue to use 1577 vmlinux for dump capture. This option should go away down the 1578 line. 1579 1580 Don't change this unless you know what you are doing. 1581 1582config RELOCATABLE 1583 bool "Build a relocatable kernel" 1584 default y 1585 ---help--- 1586 This builds a kernel image that retains relocation information 1587 so it can be loaded someplace besides the default 1MB. 1588 The relocations tend to make the kernel binary about 10% larger, 1589 but are discarded at runtime. 1590 1591 One use is for the kexec on panic case where the recovery kernel 1592 must live at a different physical address than the primary 1593 kernel. 1594 1595 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1596 it has been loaded at and the compile time physical address 1597 (CONFIG_PHYSICAL_START) is ignored. 1598 1599# Relocation on x86-32 needs some additional build support 1600config X86_NEED_RELOCS 1601 def_bool y 1602 depends on X86_32 && RELOCATABLE 1603 1604config PHYSICAL_ALIGN 1605 hex "Alignment value to which kernel should be aligned" if X86_32 1606 default "0x1000000" 1607 range 0x2000 0x1000000 1608 ---help--- 1609 This value puts the alignment restrictions on physical address 1610 where kernel is loaded and run from. Kernel is compiled for an 1611 address which meets above alignment restriction. 1612 1613 If bootloader loads the kernel at a non-aligned address and 1614 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1615 address aligned to above value and run from there. 1616 1617 If bootloader loads the kernel at a non-aligned address and 1618 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1619 load address and decompress itself to the address it has been 1620 compiled for and run from there. The address for which kernel is 1621 compiled already meets above alignment restrictions. Hence the 1622 end result is that kernel runs from a physical address meeting 1623 above alignment restrictions. 1624 1625 Don't change this unless you know what you are doing. 1626 1627config HOTPLUG_CPU 1628 bool "Support for hot-pluggable CPUs" 1629 depends on SMP && HOTPLUG 1630 ---help--- 1631 Say Y here to allow turning CPUs off and on. CPUs can be 1632 controlled through /sys/devices/system/cpu. 1633 ( Note: power management support will enable this option 1634 automatically on SMP systems. ) 1635 Say N if you want to disable CPU hotplug. 1636 1637config COMPAT_VDSO 1638 def_bool y 1639 prompt "Compat VDSO support" 1640 depends on X86_32 || IA32_EMULATION 1641 ---help--- 1642 Map the 32-bit VDSO to the predictable old-style address too. 1643 1644 Say N here if you are running a sufficiently recent glibc 1645 version (2.3.3 or later), to remove the high-mapped 1646 VDSO mapping and to exclusively use the randomized VDSO. 1647 1648 If unsure, say Y. 1649 1650config CMDLINE_BOOL 1651 bool "Built-in kernel command line" 1652 ---help--- 1653 Allow for specifying boot arguments to the kernel at 1654 build time. On some systems (e.g. embedded ones), it is 1655 necessary or convenient to provide some or all of the 1656 kernel boot arguments with the kernel itself (that is, 1657 to not rely on the boot loader to provide them.) 1658 1659 To compile command line arguments into the kernel, 1660 set this option to 'Y', then fill in the 1661 the boot arguments in CONFIG_CMDLINE. 1662 1663 Systems with fully functional boot loaders (i.e. non-embedded) 1664 should leave this option set to 'N'. 1665 1666config CMDLINE 1667 string "Built-in kernel command string" 1668 depends on CMDLINE_BOOL 1669 default "" 1670 ---help--- 1671 Enter arguments here that should be compiled into the kernel 1672 image and used at boot time. If the boot loader provides a 1673 command line at boot time, it is appended to this string to 1674 form the full kernel command line, when the system boots. 1675 1676 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 1677 change this behavior. 1678 1679 In most cases, the command line (whether built-in or provided 1680 by the boot loader) should specify the device for the root 1681 file system. 1682 1683config CMDLINE_OVERRIDE 1684 bool "Built-in command line overrides boot loader arguments" 1685 depends on CMDLINE_BOOL 1686 ---help--- 1687 Set this option to 'Y' to have the kernel ignore the boot loader 1688 command line, and use ONLY the built-in command line. 1689 1690 This is used to work around broken boot loaders. This should 1691 be set to 'N' under normal conditions. 1692 1693endmenu 1694 1695config ARCH_ENABLE_MEMORY_HOTPLUG 1696 def_bool y 1697 depends on X86_64 || (X86_32 && HIGHMEM) 1698 1699config ARCH_ENABLE_MEMORY_HOTREMOVE 1700 def_bool y 1701 depends on MEMORY_HOTPLUG 1702 1703config HAVE_ARCH_EARLY_PFN_TO_NID 1704 def_bool X86_64 1705 depends on NUMA 1706 1707config USE_PERCPU_NUMA_NODE_ID 1708 def_bool X86_64 1709 depends on NUMA 1710 1711menu "Power management and ACPI options" 1712 1713config ARCH_HIBERNATION_HEADER 1714 def_bool y 1715 depends on X86_64 && HIBERNATION 1716 1717source "kernel/power/Kconfig" 1718 1719source "drivers/acpi/Kconfig" 1720 1721source "drivers/sfi/Kconfig" 1722 1723config X86_APM_BOOT 1724 def_bool y 1725 depends on APM || APM_MODULE 1726 1727menuconfig APM 1728 tristate "APM (Advanced Power Management) BIOS support" 1729 depends on X86_32 && PM_SLEEP 1730 ---help--- 1731 APM is a BIOS specification for saving power using several different 1732 techniques. This is mostly useful for battery powered laptops with 1733 APM compliant BIOSes. If you say Y here, the system time will be 1734 reset after a RESUME operation, the /proc/apm device will provide 1735 battery status information, and user-space programs will receive 1736 notification of APM "events" (e.g. battery status change). 1737 1738 If you select "Y" here, you can disable actual use of the APM 1739 BIOS by passing the "apm=off" option to the kernel at boot time. 1740 1741 Note that the APM support is almost completely disabled for 1742 machines with more than one CPU. 1743 1744 In order to use APM, you will need supporting software. For location 1745 and more information, read <file:Documentation/power/pm.txt> and the 1746 Battery Powered Linux mini-HOWTO, available from 1747 <http://www.tldp.org/docs.html#howto>. 1748 1749 This driver does not spin down disk drives (see the hdparm(8) 1750 manpage ("man 8 hdparm") for that), and it doesn't turn off 1751 VESA-compliant "green" monitors. 1752 1753 This driver does not support the TI 4000M TravelMate and the ACER 1754 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1755 desktop machines also don't have compliant BIOSes, and this driver 1756 may cause those machines to panic during the boot phase. 1757 1758 Generally, if you don't have a battery in your machine, there isn't 1759 much point in using this driver and you should say N. If you get 1760 random kernel OOPSes or reboots that don't seem to be related to 1761 anything, try disabling/enabling this option (or disabling/enabling 1762 APM in your BIOS). 1763 1764 Some other things you should try when experiencing seemingly random, 1765 "weird" problems: 1766 1767 1) make sure that you have enough swap space and that it is 1768 enabled. 1769 2) pass the "no-hlt" option to the kernel 1770 3) switch on floating point emulation in the kernel and pass 1771 the "no387" option to the kernel 1772 4) pass the "floppy=nodma" option to the kernel 1773 5) pass the "mem=4M" option to the kernel (thereby disabling 1774 all but the first 4 MB of RAM) 1775 6) make sure that the CPU is not over clocked. 1776 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1777 8) disable the cache from your BIOS settings 1778 9) install a fan for the video card or exchange video RAM 1779 10) install a better fan for the CPU 1780 11) exchange RAM chips 1781 12) exchange the motherboard. 1782 1783 To compile this driver as a module, choose M here: the 1784 module will be called apm. 1785 1786if APM 1787 1788config APM_IGNORE_USER_SUSPEND 1789 bool "Ignore USER SUSPEND" 1790 ---help--- 1791 This option will ignore USER SUSPEND requests. On machines with a 1792 compliant APM BIOS, you want to say N. However, on the NEC Versa M 1793 series notebooks, it is necessary to say Y because of a BIOS bug. 1794 1795config APM_DO_ENABLE 1796 bool "Enable PM at boot time" 1797 ---help--- 1798 Enable APM features at boot time. From page 36 of the APM BIOS 1799 specification: "When disabled, the APM BIOS does not automatically 1800 power manage devices, enter the Standby State, enter the Suspend 1801 State, or take power saving steps in response to CPU Idle calls." 1802 This driver will make CPU Idle calls when Linux is idle (unless this 1803 feature is turned off -- see "Do CPU IDLE calls", below). This 1804 should always save battery power, but more complicated APM features 1805 will be dependent on your BIOS implementation. You may need to turn 1806 this option off if your computer hangs at boot time when using APM 1807 support, or if it beeps continuously instead of suspending. Turn 1808 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1809 T400CDT. This is off by default since most machines do fine without 1810 this feature. 1811 1812config APM_CPU_IDLE 1813 bool "Make CPU Idle calls when idle" 1814 ---help--- 1815 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 1816 On some machines, this can activate improved power savings, such as 1817 a slowed CPU clock rate, when the machine is idle. These idle calls 1818 are made after the idle loop has run for some length of time (e.g., 1819 333 mS). On some machines, this will cause a hang at boot time or 1820 whenever the CPU becomes idle. (On machines with more than one CPU, 1821 this option does nothing.) 1822 1823config APM_DISPLAY_BLANK 1824 bool "Enable console blanking using APM" 1825 ---help--- 1826 Enable console blanking using the APM. Some laptops can use this to 1827 turn off the LCD backlight when the screen blanker of the Linux 1828 virtual console blanks the screen. Note that this is only used by 1829 the virtual console screen blanker, and won't turn off the backlight 1830 when using the X Window system. This also doesn't have anything to 1831 do with your VESA-compliant power-saving monitor. Further, this 1832 option doesn't work for all laptops -- it might not turn off your 1833 backlight at all, or it might print a lot of errors to the console, 1834 especially if you are using gpm. 1835 1836config APM_ALLOW_INTS 1837 bool "Allow interrupts during APM BIOS calls" 1838 ---help--- 1839 Normally we disable external interrupts while we are making calls to 1840 the APM BIOS as a measure to lessen the effects of a badly behaving 1841 BIOS implementation. The BIOS should reenable interrupts if it 1842 needs to. Unfortunately, some BIOSes do not -- especially those in 1843 many of the newer IBM Thinkpads. If you experience hangs when you 1844 suspend, try setting this to Y. Otherwise, say N. 1845 1846endif # APM 1847 1848source "arch/x86/kernel/cpu/cpufreq/Kconfig" 1849 1850source "drivers/cpuidle/Kconfig" 1851 1852source "drivers/idle/Kconfig" 1853 1854endmenu 1855 1856 1857menu "Bus options (PCI etc.)" 1858 1859config PCI 1860 bool "PCI support" 1861 default y 1862 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC) 1863 ---help--- 1864 Find out whether you have a PCI motherboard. PCI is the name of a 1865 bus system, i.e. the way the CPU talks to the other stuff inside 1866 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 1867 VESA. If you have PCI, say Y, otherwise N. 1868 1869choice 1870 prompt "PCI access mode" 1871 depends on X86_32 && PCI 1872 default PCI_GOANY 1873 ---help--- 1874 On PCI systems, the BIOS can be used to detect the PCI devices and 1875 determine their configuration. However, some old PCI motherboards 1876 have BIOS bugs and may crash if this is done. Also, some embedded 1877 PCI-based systems don't have any BIOS at all. Linux can also try to 1878 detect the PCI hardware directly without using the BIOS. 1879 1880 With this option, you can specify how Linux should detect the 1881 PCI devices. If you choose "BIOS", the BIOS will be used, 1882 if you choose "Direct", the BIOS won't be used, and if you 1883 choose "MMConfig", then PCI Express MMCONFIG will be used. 1884 If you choose "Any", the kernel will try MMCONFIG, then the 1885 direct access method and falls back to the BIOS if that doesn't 1886 work. If unsure, go with the default, which is "Any". 1887 1888config PCI_GOBIOS 1889 bool "BIOS" 1890 1891config PCI_GOMMCONFIG 1892 bool "MMConfig" 1893 1894config PCI_GODIRECT 1895 bool "Direct" 1896 1897config PCI_GOOLPC 1898 bool "OLPC" 1899 depends on OLPC 1900 1901config PCI_GOANY 1902 bool "Any" 1903 1904endchoice 1905 1906config PCI_BIOS 1907 def_bool y 1908 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 1909 1910# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 1911config PCI_DIRECT 1912 def_bool y 1913 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC)) 1914 1915config PCI_MMCONFIG 1916 def_bool y 1917 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 1918 1919config PCI_OLPC 1920 def_bool y 1921 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 1922 1923config PCI_DOMAINS 1924 def_bool y 1925 depends on PCI 1926 1927config PCI_MMCONFIG 1928 bool "Support mmconfig PCI config space access" 1929 depends on X86_64 && PCI && ACPI 1930 1931config PCI_CNB20LE_QUIRK 1932 bool "Read CNB20LE Host Bridge Windows" 1933 depends on PCI 1934 help 1935 Read the PCI windows out of the CNB20LE host bridge. This allows 1936 PCI hotplug to work on systems with the CNB20LE chipset which do 1937 not have ACPI. 1938 1939config DMAR 1940 bool "Support for DMA Remapping Devices (EXPERIMENTAL)" 1941 depends on PCI_MSI && ACPI && EXPERIMENTAL 1942 help 1943 DMA remapping (DMAR) devices support enables independent address 1944 translations for Direct Memory Access (DMA) from devices. 1945 These DMA remapping devices are reported via ACPI tables 1946 and include PCI device scope covered by these DMA 1947 remapping devices. 1948 1949config DMAR_DEFAULT_ON 1950 def_bool y 1951 prompt "Enable DMA Remapping Devices by default" 1952 depends on DMAR 1953 help 1954 Selecting this option will enable a DMAR device at boot time if 1955 one is found. If this option is not selected, DMAR support can 1956 be enabled by passing intel_iommu=on to the kernel. It is 1957 recommended you say N here while the DMAR code remains 1958 experimental. 1959 1960config DMAR_BROKEN_GFX_WA 1961 bool "Workaround broken graphics drivers (going away soon)" 1962 depends on DMAR && BROKEN 1963 ---help--- 1964 Current Graphics drivers tend to use physical address 1965 for DMA and avoid using DMA APIs. Setting this config 1966 option permits the IOMMU driver to set a unity map for 1967 all the OS-visible memory. Hence the driver can continue 1968 to use physical addresses for DMA, at least until this 1969 option is removed in the 2.6.32 kernel. 1970 1971config DMAR_FLOPPY_WA 1972 def_bool y 1973 depends on DMAR 1974 ---help--- 1975 Floppy disk drivers are known to bypass DMA API calls 1976 thereby failing to work when IOMMU is enabled. This 1977 workaround will setup a 1:1 mapping for the first 1978 16MiB to make floppy (an ISA device) work. 1979 1980config INTR_REMAP 1981 bool "Support for Interrupt Remapping (EXPERIMENTAL)" 1982 depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL 1983 ---help--- 1984 Supports Interrupt remapping for IO-APIC and MSI devices. 1985 To use x2apic mode in the CPU's which support x2APIC enhancements or 1986 to support platforms with CPU's having > 8 bit APIC ID, say Y. 1987 1988source "drivers/pci/pcie/Kconfig" 1989 1990source "drivers/pci/Kconfig" 1991 1992# x86_64 have no ISA slots, but do have ISA-style DMA. 1993config ISA_DMA_API 1994 def_bool y 1995 1996if X86_32 1997 1998config ISA 1999 bool "ISA support" 2000 ---help--- 2001 Find out whether you have ISA slots on your motherboard. ISA is the 2002 name of a bus system, i.e. the way the CPU talks to the other stuff 2003 inside your box. Other bus systems are PCI, EISA, MicroChannel 2004 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2005 newer boards don't support it. If you have ISA, say Y, otherwise N. 2006 2007config EISA 2008 bool "EISA support" 2009 depends on ISA 2010 ---help--- 2011 The Extended Industry Standard Architecture (EISA) bus was 2012 developed as an open alternative to the IBM MicroChannel bus. 2013 2014 The EISA bus provided some of the features of the IBM MicroChannel 2015 bus while maintaining backward compatibility with cards made for 2016 the older ISA bus. The EISA bus saw limited use between 1988 and 2017 1995 when it was made obsolete by the PCI bus. 2018 2019 Say Y here if you are building a kernel for an EISA-based machine. 2020 2021 Otherwise, say N. 2022 2023source "drivers/eisa/Kconfig" 2024 2025config MCA 2026 bool "MCA support" 2027 ---help--- 2028 MicroChannel Architecture is found in some IBM PS/2 machines and 2029 laptops. It is a bus system similar to PCI or ISA. See 2030 <file:Documentation/mca.txt> (and especially the web page given 2031 there) before attempting to build an MCA bus kernel. 2032 2033source "drivers/mca/Kconfig" 2034 2035config SCx200 2036 tristate "NatSemi SCx200 support" 2037 ---help--- 2038 This provides basic support for National Semiconductor's 2039 (now AMD's) Geode processors. The driver probes for the 2040 PCI-IDs of several on-chip devices, so its a good dependency 2041 for other scx200_* drivers. 2042 2043 If compiled as a module, the driver is named scx200. 2044 2045config SCx200HR_TIMER 2046 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2047 depends on SCx200 2048 default y 2049 ---help--- 2050 This driver provides a clocksource built upon the on-chip 2051 27MHz high-resolution timer. Its also a workaround for 2052 NSC Geode SC-1100's buggy TSC, which loses time when the 2053 processor goes idle (as is done by the scheduler). The 2054 other workaround is idle=poll boot option. 2055 2056config OLPC 2057 bool "One Laptop Per Child support" 2058 select GPIOLIB 2059 ---help--- 2060 Add support for detecting the unique features of the OLPC 2061 XO hardware. 2062 2063config OLPC_OPENFIRMWARE 2064 bool "Support for OLPC's Open Firmware" 2065 depends on !X86_64 && !X86_PAE 2066 default y if OLPC 2067 help 2068 This option adds support for the implementation of Open Firmware 2069 that is used on the OLPC XO-1 Children's Machine. 2070 If unsure, say N here. 2071 2072endif # X86_32 2073 2074config K8_NB 2075 def_bool y 2076 depends on CPU_SUP_AMD && PCI 2077 2078source "drivers/pcmcia/Kconfig" 2079 2080source "drivers/pci/hotplug/Kconfig" 2081 2082endmenu 2083 2084 2085menu "Executable file formats / Emulations" 2086 2087source "fs/Kconfig.binfmt" 2088 2089config IA32_EMULATION 2090 bool "IA32 Emulation" 2091 depends on X86_64 2092 select COMPAT_BINFMT_ELF 2093 ---help--- 2094 Include code to run 32-bit programs under a 64-bit kernel. You should 2095 likely turn this on, unless you're 100% sure that you don't have any 2096 32-bit programs left. 2097 2098config IA32_AOUT 2099 tristate "IA32 a.out support" 2100 depends on IA32_EMULATION 2101 ---help--- 2102 Support old a.out binaries in the 32bit emulation. 2103 2104config COMPAT 2105 def_bool y 2106 depends on IA32_EMULATION 2107 2108config COMPAT_FOR_U64_ALIGNMENT 2109 def_bool COMPAT 2110 depends on X86_64 2111 2112config SYSVIPC_COMPAT 2113 def_bool y 2114 depends on COMPAT && SYSVIPC 2115 2116endmenu 2117 2118 2119config HAVE_ATOMIC_IOMAP 2120 def_bool y 2121 depends on X86_32 2122 2123source "net/Kconfig" 2124 2125source "drivers/Kconfig" 2126 2127source "drivers/firmware/Kconfig" 2128 2129source "fs/Kconfig" 2130 2131source "arch/x86/Kconfig.debug" 2132 2133source "security/Kconfig" 2134 2135source "crypto/Kconfig" 2136 2137source "arch/x86/kvm/Kconfig" 2138 2139source "lib/Kconfig" 2140