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 select CLKSRC_I8253 12 13config X86_64 14 def_bool 64BIT 15 16### Arch settings 17config X86 18 def_bool y 19 select HAVE_AOUT if X86_32 20 select HAVE_UNSTABLE_SCHED_CLOCK 21 select HAVE_IDE 22 select HAVE_OPROFILE 23 select HAVE_PCSPKR_PLATFORM 24 select HAVE_PERF_EVENTS 25 select HAVE_IRQ_WORK 26 select HAVE_IOREMAP_PROT 27 select HAVE_KPROBES 28 select HAVE_MEMBLOCK 29 select HAVE_MEMBLOCK_NODE_MAP 30 select ARCH_DISCARD_MEMBLOCK 31 select ARCH_WANT_OPTIONAL_GPIOLIB 32 select ARCH_WANT_FRAME_POINTERS 33 select HAVE_DMA_ATTRS 34 select HAVE_KRETPROBES 35 select HAVE_OPTPROBES 36 select HAVE_FTRACE_MCOUNT_RECORD 37 select HAVE_C_RECORDMCOUNT 38 select HAVE_DYNAMIC_FTRACE 39 select HAVE_FUNCTION_TRACER 40 select HAVE_FUNCTION_GRAPH_TRACER 41 select HAVE_FUNCTION_GRAPH_FP_TEST 42 select HAVE_FUNCTION_TRACE_MCOUNT_TEST 43 select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE 44 select HAVE_SYSCALL_TRACEPOINTS 45 select HAVE_KVM 46 select HAVE_ARCH_KGDB 47 select HAVE_ARCH_TRACEHOOK 48 select HAVE_GENERIC_DMA_COHERENT if X86_32 49 select HAVE_EFFICIENT_UNALIGNED_ACCESS 50 select USER_STACKTRACE_SUPPORT 51 select HAVE_REGS_AND_STACK_ACCESS_API 52 select HAVE_DMA_API_DEBUG 53 select HAVE_KERNEL_GZIP 54 select HAVE_KERNEL_BZIP2 55 select HAVE_KERNEL_LZMA 56 select HAVE_KERNEL_XZ 57 select HAVE_KERNEL_LZO 58 select HAVE_HW_BREAKPOINT 59 select HAVE_MIXED_BREAKPOINTS_REGS 60 select PERF_EVENTS 61 select HAVE_PERF_EVENTS_NMI 62 select ANON_INODES 63 select HAVE_ALIGNED_STRUCT_PAGE if SLUB && !M386 64 select HAVE_CMPXCHG_LOCAL if !M386 65 select HAVE_CMPXCHG_DOUBLE 66 select HAVE_ARCH_KMEMCHECK 67 select HAVE_USER_RETURN_NOTIFIER 68 select ARCH_BINFMT_ELF_RANDOMIZE_PIE 69 select HAVE_ARCH_JUMP_LABEL 70 select HAVE_TEXT_POKE_SMP 71 select HAVE_GENERIC_HARDIRQS 72 select SPARSE_IRQ 73 select GENERIC_FIND_FIRST_BIT 74 select GENERIC_IRQ_PROBE 75 select GENERIC_PENDING_IRQ if SMP 76 select GENERIC_IRQ_SHOW 77 select GENERIC_CLOCKEVENTS_MIN_ADJUST 78 select IRQ_FORCED_THREADING 79 select USE_GENERIC_SMP_HELPERS if SMP 80 select HAVE_BPF_JIT if (X86_64 && NET) 81 select CLKEVT_I8253 82 select ARCH_HAVE_NMI_SAFE_CMPXCHG 83 select GENERIC_IOMAP 84 select DCACHE_WORD_ACCESS if !DEBUG_PAGEALLOC 85 select HAVE_ARCH_MMAP_RND_BITS if MMU 86 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 87 select HAVE_ARCH_SECCOMP_FILTER 88 89config INSTRUCTION_DECODER 90 def_bool (KPROBES || PERF_EVENTS) 91 92config OUTPUT_FORMAT 93 string 94 default "elf32-i386" if X86_32 95 default "elf64-x86-64" if X86_64 96 97config ARCH_DEFCONFIG 98 string 99 default "arch/x86/configs/i386_defconfig" if X86_32 100 default "arch/x86/configs/x86_64_defconfig" if X86_64 101 102config GENERIC_CMOS_UPDATE 103 def_bool y 104 105config CLOCKSOURCE_WATCHDOG 106 def_bool y 107 108config GENERIC_CLOCKEVENTS 109 def_bool y 110 111config ARCH_CLOCKSOURCE_DATA 112 def_bool y 113 depends on X86_64 114 115config GENERIC_CLOCKEVENTS_BROADCAST 116 def_bool y 117 depends on X86_64 || (X86_32 && X86_LOCAL_APIC) 118 119config LOCKDEP_SUPPORT 120 def_bool y 121 122config STACKTRACE_SUPPORT 123 def_bool y 124 125config HAVE_LATENCYTOP_SUPPORT 126 def_bool y 127 128config MMU 129 def_bool y 130 131config ARCH_MMAP_RND_BITS_MIN 132 default 28 if 64BIT 133 default 8 134 135config ARCH_MMAP_RND_BITS_MAX 136 default 32 if 64BIT 137 default 16 138 139config ARCH_MMAP_RND_COMPAT_BITS_MIN 140 default 8 141 142config ARCH_MMAP_RND_COMPAT_BITS_MAX 143 default 16 144 145config SBUS 146 bool 147 148config NEED_DMA_MAP_STATE 149 def_bool (X86_64 || INTEL_IOMMU || DMA_API_DEBUG) 150 151config NEED_SG_DMA_LENGTH 152 def_bool y 153 154config GENERIC_ISA_DMA 155 def_bool ISA_DMA_API 156 157config GENERIC_BUG 158 def_bool y 159 depends on BUG 160 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 161 162config GENERIC_BUG_RELATIVE_POINTERS 163 bool 164 165config GENERIC_HWEIGHT 166 def_bool y 167 168config GENERIC_GPIO 169 bool 170 171config ARCH_MAY_HAVE_PC_FDC 172 def_bool ISA_DMA_API 173 174config RWSEM_GENERIC_SPINLOCK 175 def_bool !X86_XADD 176 177config RWSEM_XCHGADD_ALGORITHM 178 def_bool X86_XADD 179 180config ARCH_HAS_CPU_IDLE_WAIT 181 def_bool y 182 183config GENERIC_CALIBRATE_DELAY 184 def_bool y 185 186config GENERIC_TIME_VSYSCALL 187 bool 188 default X86_64 189 190config ARCH_HAS_CPU_RELAX 191 def_bool y 192 193config ARCH_HAS_DEFAULT_IDLE 194 def_bool y 195 196config ARCH_HAS_CACHE_LINE_SIZE 197 def_bool y 198 199config ARCH_HAS_CPU_AUTOPROBE 200 def_bool y 201 202config HAVE_SETUP_PER_CPU_AREA 203 def_bool y 204 205config NEED_PER_CPU_EMBED_FIRST_CHUNK 206 def_bool y 207 208config NEED_PER_CPU_PAGE_FIRST_CHUNK 209 def_bool y 210 211config ARCH_HIBERNATION_POSSIBLE 212 def_bool y 213 214config ARCH_SUSPEND_POSSIBLE 215 def_bool y 216 217config ZONE_DMA32 218 bool 219 default X86_64 220 221config AUDIT_ARCH 222 bool 223 default X86_64 224 225config ARCH_SUPPORTS_OPTIMIZED_INLINING 226 def_bool y 227 228config ARCH_SUPPORTS_DEBUG_PAGEALLOC 229 def_bool y 230 231config HAVE_INTEL_TXT 232 def_bool y 233 depends on EXPERIMENTAL && INTEL_IOMMU && ACPI 234 235config X86_32_SMP 236 def_bool y 237 depends on X86_32 && SMP 238 239config X86_64_SMP 240 def_bool y 241 depends on X86_64 && SMP 242 243config X86_HT 244 def_bool y 245 depends on SMP 246 247config X86_32_LAZY_GS 248 def_bool y 249 depends on X86_32 && !CC_STACKPROTECTOR 250 251config ARCH_HWEIGHT_CFLAGS 252 string 253 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32 254 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_64 255 256config KTIME_SCALAR 257 def_bool X86_32 258 259config ARCH_CPU_PROBE_RELEASE 260 def_bool y 261 depends on HOTPLUG_CPU 262 263source "init/Kconfig" 264source "kernel/Kconfig.freezer" 265 266menu "Processor type and features" 267 268config ZONE_DMA 269 bool "DMA memory allocation support" if EXPERT 270 default y 271 help 272 DMA memory allocation support allows devices with less than 32-bit 273 addressing to allocate within the first 16MB of address space. 274 Disable if no such devices will be used. 275 276 If unsure, say Y. 277 278source "kernel/time/Kconfig" 279 280config SMP 281 bool "Symmetric multi-processing support" 282 ---help--- 283 This enables support for systems with more than one CPU. If you have 284 a system with only one CPU, like most personal computers, say N. If 285 you have a system with more than one CPU, say Y. 286 287 If you say N here, the kernel will run on single and multiprocessor 288 machines, but will use only one CPU of a multiprocessor machine. If 289 you say Y here, the kernel will run on many, but not all, 290 singleprocessor machines. On a singleprocessor machine, the kernel 291 will run faster if you say N here. 292 293 Note that if you say Y here and choose architecture "586" or 294 "Pentium" under "Processor family", the kernel will not work on 486 295 architectures. Similarly, multiprocessor kernels for the "PPro" 296 architecture may not work on all Pentium based boards. 297 298 People using multiprocessor machines who say Y here should also say 299 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 300 Management" code will be disabled if you say Y here. 301 302 See also <file:Documentation/x86/i386/IO-APIC.txt>, 303 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 304 <http://www.tldp.org/docs.html#howto>. 305 306 If you don't know what to do here, say N. 307 308config X86_X2APIC 309 bool "Support x2apic" 310 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP 311 ---help--- 312 This enables x2apic support on CPUs that have this feature. 313 314 This allows 32-bit apic IDs (so it can support very large systems), 315 and accesses the local apic via MSRs not via mmio. 316 317 If you don't know what to do here, say N. 318 319config X86_MPPARSE 320 bool "Enable MPS table" if ACPI 321 default y 322 depends on X86_LOCAL_APIC 323 ---help--- 324 For old smp systems that do not have proper acpi support. Newer systems 325 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 326 327config X86_BIGSMP 328 bool "Support for big SMP systems with more than 8 CPUs" 329 depends on X86_32 && SMP 330 ---help--- 331 This option is needed for the systems that have more than 8 CPUs 332 333config ARCH_GOLDFISH 334 def_bool y 335 depends on X86_GOLDFISH 336 337if X86_32 338config X86_EXTENDED_PLATFORM 339 bool "Support for extended (non-PC) x86 platforms" 340 default y 341 ---help--- 342 If you disable this option then the kernel will only support 343 standard PC platforms. (which covers the vast majority of 344 systems out there.) 345 346 If you enable this option then you'll be able to select support 347 for the following (non-PC) 32 bit x86 platforms: 348 AMD Elan 349 NUMAQ (IBM/Sequent) 350 RDC R-321x SoC 351 SGI 320/540 (Visual Workstation) 352 Summit/EXA (IBM x440) 353 Unisys ES7000 IA32 series 354 Moorestown MID devices 355 356 If you have one of these systems, or if you want to build a 357 generic distribution kernel, say Y here - otherwise say N. 358endif 359 360if X86_64 361config X86_EXTENDED_PLATFORM 362 bool "Support for extended (non-PC) x86 platforms" 363 default y 364 ---help--- 365 If you disable this option then the kernel will only support 366 standard PC platforms. (which covers the vast majority of 367 systems out there.) 368 369 If you enable this option then you'll be able to select support 370 for the following (non-PC) 64 bit x86 platforms: 371 Numascale NumaChip 372 ScaleMP vSMP 373 SGI Ultraviolet 374 375 If you have one of these systems, or if you want to build a 376 generic distribution kernel, say Y here - otherwise say N. 377endif 378# This is an alphabetically sorted list of 64 bit extended platforms 379# Please maintain the alphabetic order if and when there are additions 380config X86_NUMACHIP 381 bool "Numascale NumaChip" 382 depends on X86_64 383 depends on X86_EXTENDED_PLATFORM 384 depends on NUMA 385 depends on SMP 386 depends on X86_X2APIC 387 ---help--- 388 Adds support for Numascale NumaChip large-SMP systems. Needed to 389 enable more than ~168 cores. 390 If you don't have one of these, you should say N here. 391 392config X86_VSMP 393 bool "ScaleMP vSMP" 394 select PARAVIRT_GUEST 395 select PARAVIRT 396 depends on X86_64 && PCI 397 depends on X86_EXTENDED_PLATFORM 398 ---help--- 399 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 400 supposed to run on these EM64T-based machines. Only choose this option 401 if you have one of these machines. 402 403config X86_UV 404 bool "SGI Ultraviolet" 405 depends on X86_64 406 depends on X86_EXTENDED_PLATFORM 407 depends on NUMA 408 depends on X86_X2APIC 409 ---help--- 410 This option is needed in order to support SGI Ultraviolet systems. 411 If you don't have one of these, you should say N here. 412 413# Following is an alphabetically sorted list of 32 bit extended platforms 414# Please maintain the alphabetic order if and when there are additions 415 416config X86_GOLDFISH 417 bool "Goldfish (Virtual Platform)" 418 depends on X86_32 419 help 420 This option would make Goldfish virtual platform available. 421 422config X86_INTEL_CE 423 bool "CE4100 TV platform" 424 depends on PCI 425 depends on PCI_GODIRECT 426 depends on X86_32 427 depends on X86_EXTENDED_PLATFORM 428 select X86_REBOOTFIXUPS 429 select OF 430 select OF_EARLY_FLATTREE 431 select IRQ_DOMAIN 432 ---help--- 433 Select for the Intel CE media processor (CE4100) SOC. 434 This option compiles in support for the CE4100 SOC for settop 435 boxes and media devices. 436 437config X86_WANT_INTEL_MID 438 bool "Intel MID platform support" 439 depends on X86_32 440 depends on X86_EXTENDED_PLATFORM 441 ---help--- 442 Select to build a kernel capable of supporting Intel MID platform 443 systems which do not have the PCI legacy interfaces (Moorestown, 444 Medfield). If you are building for a PC class system say N here. 445 446if X86_WANT_INTEL_MID 447 448config X86_INTEL_MID 449 bool 450 451config X86_MDFLD 452 bool "Medfield MID platform" 453 depends on PCI 454 depends on PCI_GOANY 455 depends on X86_IO_APIC 456 select X86_INTEL_MID 457 select SFI 458 select DW_APB_TIMER 459 select APB_TIMER 460 select I2C 461 select SPI 462 select INTEL_SCU_IPC 463 select X86_PLATFORM_DEVICES 464 select MFD_INTEL_MSIC 465 ---help--- 466 Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin 467 Internet Device(MID) platform. 468 Unlike standard x86 PCs, Medfield does not have many legacy devices 469 nor standard legacy replacement devices/features. e.g. Medfield does 470 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports. 471 472endif 473 474config X86_RDC321X 475 bool "RDC R-321x SoC" 476 depends on X86_32 477 depends on X86_EXTENDED_PLATFORM 478 select M486 479 select X86_REBOOTFIXUPS 480 ---help--- 481 This option is needed for RDC R-321x system-on-chip, also known 482 as R-8610-(G). 483 If you don't have one of these chips, you should say N here. 484 485config X86_32_NON_STANDARD 486 bool "Support non-standard 32-bit SMP architectures" 487 depends on X86_32 && SMP 488 depends on X86_EXTENDED_PLATFORM 489 ---help--- 490 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default 491 subarchitectures. It is intended for a generic binary kernel. 492 if you select them all, kernel will probe it one by one. and will 493 fallback to default. 494 495# Alphabetically sorted list of Non standard 32 bit platforms 496 497config X86_NUMAQ 498 bool "NUMAQ (IBM/Sequent)" 499 depends on X86_32_NON_STANDARD 500 depends on PCI 501 select NUMA 502 select X86_MPPARSE 503 ---help--- 504 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent) 505 NUMA multiquad box. This changes the way that processors are 506 bootstrapped, and uses Clustered Logical APIC addressing mode instead 507 of Flat Logical. You will need a new lynxer.elf file to flash your 508 firmware with - send email to <Martin.Bligh@us.ibm.com>. 509 510config X86_SUPPORTS_MEMORY_FAILURE 511 def_bool y 512 # MCE code calls memory_failure(): 513 depends on X86_MCE 514 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 515 depends on !X86_NUMAQ 516 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 517 depends on X86_64 || !SPARSEMEM 518 select ARCH_SUPPORTS_MEMORY_FAILURE 519 520config X86_VISWS 521 bool "SGI 320/540 (Visual Workstation)" 522 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT 523 depends on X86_32_NON_STANDARD 524 ---help--- 525 The SGI Visual Workstation series is an IA32-based workstation 526 based on SGI systems chips with some legacy PC hardware attached. 527 528 Say Y here to create a kernel to run on the SGI 320 or 540. 529 530 A kernel compiled for the Visual Workstation will run on general 531 PCs as well. See <file:Documentation/sgi-visws.txt> for details. 532 533config X86_SUMMIT 534 bool "Summit/EXA (IBM x440)" 535 depends on X86_32_NON_STANDARD 536 ---help--- 537 This option is needed for IBM systems that use the Summit/EXA chipset. 538 In particular, it is needed for the x440. 539 540config X86_ES7000 541 bool "Unisys ES7000 IA32 series" 542 depends on X86_32_NON_STANDARD && X86_BIGSMP 543 ---help--- 544 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is 545 supposed to run on an IA32-based Unisys ES7000 system. 546 547config X86_32_IRIS 548 tristate "Eurobraille/Iris poweroff module" 549 depends on X86_32 550 ---help--- 551 The Iris machines from EuroBraille do not have APM or ACPI support 552 to shut themselves down properly. A special I/O sequence is 553 needed to do so, which is what this module does at 554 kernel shutdown. 555 556 This is only for Iris machines from EuroBraille. 557 558 If unused, say N. 559 560config SCHED_OMIT_FRAME_POINTER 561 def_bool y 562 prompt "Single-depth WCHAN output" 563 depends on X86 564 ---help--- 565 Calculate simpler /proc/<PID>/wchan values. If this option 566 is disabled then wchan values will recurse back to the 567 caller function. This provides more accurate wchan values, 568 at the expense of slightly more scheduling overhead. 569 570 If in doubt, say "Y". 571 572menuconfig PARAVIRT_GUEST 573 bool "Paravirtualized guest support" 574 ---help--- 575 Say Y here to get to see options related to running Linux under 576 various hypervisors. This option alone does not add any kernel code. 577 578 If you say N, all options in this submenu will be skipped and disabled. 579 580if PARAVIRT_GUEST 581 582config PARAVIRT_TIME_ACCOUNTING 583 bool "Paravirtual steal time accounting" 584 select PARAVIRT 585 default n 586 ---help--- 587 Select this option to enable fine granularity task steal time 588 accounting. Time spent executing other tasks in parallel with 589 the current vCPU is discounted from the vCPU power. To account for 590 that, there can be a small performance impact. 591 592 If in doubt, say N here. 593 594source "arch/x86/xen/Kconfig" 595 596config KVM_CLOCK 597 bool "KVM paravirtualized clock" 598 select PARAVIRT 599 select PARAVIRT_CLOCK 600 ---help--- 601 Turning on this option will allow you to run a paravirtualized clock 602 when running over the KVM hypervisor. Instead of relying on a PIT 603 (or probably other) emulation by the underlying device model, the host 604 provides the guest with timing infrastructure such as time of day, and 605 system time 606 607config KVM_GUEST 608 bool "KVM Guest support" 609 select PARAVIRT 610 ---help--- 611 This option enables various optimizations for running under the KVM 612 hypervisor. 613 614source "arch/x86/lguest/Kconfig" 615 616config PARAVIRT 617 bool "Enable paravirtualization code" 618 ---help--- 619 This changes the kernel so it can modify itself when it is run 620 under a hypervisor, potentially improving performance significantly 621 over full virtualization. However, when run without a hypervisor 622 the kernel is theoretically slower and slightly larger. 623 624config PARAVIRT_SPINLOCKS 625 bool "Paravirtualization layer for spinlocks" 626 depends on PARAVIRT && SMP && EXPERIMENTAL 627 ---help--- 628 Paravirtualized spinlocks allow a pvops backend to replace the 629 spinlock implementation with something virtualization-friendly 630 (for example, block the virtual CPU rather than spinning). 631 632 Unfortunately the downside is an up to 5% performance hit on 633 native kernels, with various workloads. 634 635 If you are unsure how to answer this question, answer N. 636 637config PARAVIRT_CLOCK 638 bool 639 640endif 641 642config PARAVIRT_DEBUG 643 bool "paravirt-ops debugging" 644 depends on PARAVIRT && DEBUG_KERNEL 645 ---help--- 646 Enable to debug paravirt_ops internals. Specifically, BUG if 647 a paravirt_op is missing when it is called. 648 649config NO_BOOTMEM 650 def_bool y 651 652config MEMTEST 653 bool "Memtest" 654 ---help--- 655 This option adds a kernel parameter 'memtest', which allows memtest 656 to be set. 657 memtest=0, mean disabled; -- default 658 memtest=1, mean do 1 test pattern; 659 ... 660 memtest=4, mean do 4 test patterns. 661 If you are unsure how to answer this question, answer N. 662 663config X86_SUMMIT_NUMA 664 def_bool y 665 depends on X86_32 && NUMA && X86_32_NON_STANDARD 666 667config X86_CYCLONE_TIMER 668 def_bool y 669 depends on X86_SUMMIT 670 671source "arch/x86/Kconfig.cpu" 672 673config HPET_TIMER 674 def_bool X86_64 675 prompt "HPET Timer Support" if X86_32 676 ---help--- 677 Use the IA-PC HPET (High Precision Event Timer) to manage 678 time in preference to the PIT and RTC, if a HPET is 679 present. 680 HPET is the next generation timer replacing legacy 8254s. 681 The HPET provides a stable time base on SMP 682 systems, unlike the TSC, but it is more expensive to access, 683 as it is off-chip. You can find the HPET spec at 684 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>. 685 686 You can safely choose Y here. However, HPET will only be 687 activated if the platform and the BIOS support this feature. 688 Otherwise the 8254 will be used for timing services. 689 690 Choose N to continue using the legacy 8254 timer. 691 692config HPET_EMULATE_RTC 693 def_bool y 694 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 695 696config APB_TIMER 697 def_bool y if X86_INTEL_MID 698 prompt "Intel MID APB Timer Support" if X86_INTEL_MID 699 select DW_APB_TIMER 700 depends on X86_INTEL_MID && SFI 701 help 702 APB timer is the replacement for 8254, HPET on X86 MID platforms. 703 The APBT provides a stable time base on SMP 704 systems, unlike the TSC, but it is more expensive to access, 705 as it is off-chip. APB timers are always running regardless of CPU 706 C states, they are used as per CPU clockevent device when possible. 707 708# Mark as expert because too many people got it wrong. 709# The code disables itself when not needed. 710config DMI 711 default y 712 bool "Enable DMI scanning" if EXPERT 713 ---help--- 714 Enabled scanning of DMI to identify machine quirks. Say Y 715 here unless you have verified that your setup is not 716 affected by entries in the DMI blacklist. Required by PNP 717 BIOS code. 718 719config GART_IOMMU 720 bool "GART IOMMU support" if EXPERT 721 default y 722 select SWIOTLB 723 depends on X86_64 && PCI && AMD_NB 724 ---help--- 725 Support for full DMA access of devices with 32bit memory access only 726 on systems with more than 3GB. This is usually needed for USB, 727 sound, many IDE/SATA chipsets and some other devices. 728 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART 729 based hardware IOMMU and a software bounce buffer based IOMMU used 730 on Intel systems and as fallback. 731 The code is only active when needed (enough memory and limited 732 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified 733 too. 734 735config CALGARY_IOMMU 736 bool "IBM Calgary IOMMU support" 737 select SWIOTLB 738 depends on X86_64 && PCI && EXPERIMENTAL 739 ---help--- 740 Support for hardware IOMMUs in IBM's xSeries x366 and x460 741 systems. Needed to run systems with more than 3GB of memory 742 properly with 32-bit PCI devices that do not support DAC 743 (Double Address Cycle). Calgary also supports bus level 744 isolation, where all DMAs pass through the IOMMU. This 745 prevents them from going anywhere except their intended 746 destination. This catches hard-to-find kernel bugs and 747 mis-behaving drivers and devices that do not use the DMA-API 748 properly to set up their DMA buffers. The IOMMU can be 749 turned off at boot time with the iommu=off parameter. 750 Normally the kernel will make the right choice by itself. 751 If unsure, say Y. 752 753config CALGARY_IOMMU_ENABLED_BY_DEFAULT 754 def_bool y 755 prompt "Should Calgary be enabled by default?" 756 depends on CALGARY_IOMMU 757 ---help--- 758 Should Calgary be enabled by default? if you choose 'y', Calgary 759 will be used (if it exists). If you choose 'n', Calgary will not be 760 used even if it exists. If you choose 'n' and would like to use 761 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 762 If unsure, say Y. 763 764# need this always selected by IOMMU for the VIA workaround 765config SWIOTLB 766 def_bool y if X86_64 767 ---help--- 768 Support for software bounce buffers used on x86-64 systems 769 which don't have a hardware IOMMU (e.g. the current generation 770 of Intel's x86-64 CPUs). Using this PCI devices which can only 771 access 32-bits of memory can be used on systems with more than 772 3 GB of memory. If unsure, say Y. 773 774config IOMMU_HELPER 775 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU) 776 777config MAXSMP 778 bool "Enable Maximum number of SMP Processors and NUMA Nodes" 779 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL 780 select CPUMASK_OFFSTACK 781 ---help--- 782 Enable maximum number of CPUS and NUMA Nodes for this architecture. 783 If unsure, say N. 784 785config NR_CPUS 786 int "Maximum number of CPUs" if SMP && !MAXSMP 787 range 2 8 if SMP && X86_32 && !X86_BIGSMP 788 range 2 512 if SMP && !MAXSMP 789 default "1" if !SMP 790 default "4096" if MAXSMP 791 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000) 792 default "8" if SMP 793 ---help--- 794 This allows you to specify the maximum number of CPUs which this 795 kernel will support. The maximum supported value is 512 and the 796 minimum value which makes sense is 2. 797 798 This is purely to save memory - each supported CPU adds 799 approximately eight kilobytes to the kernel image. 800 801config SCHED_SMT 802 bool "SMT (Hyperthreading) scheduler support" 803 depends on X86_HT 804 ---help--- 805 SMT scheduler support improves the CPU scheduler's decision making 806 when dealing with Intel Pentium 4 chips with HyperThreading at a 807 cost of slightly increased overhead in some places. If unsure say 808 N here. 809 810config SCHED_MC 811 def_bool y 812 prompt "Multi-core scheduler support" 813 depends on X86_HT 814 ---help--- 815 Multi-core scheduler support improves the CPU scheduler's decision 816 making when dealing with multi-core CPU chips at a cost of slightly 817 increased overhead in some places. If unsure say N here. 818 819config IRQ_TIME_ACCOUNTING 820 bool "Fine granularity task level IRQ time accounting" 821 default n 822 ---help--- 823 Select this option to enable fine granularity task irq time 824 accounting. This is done by reading a timestamp on each 825 transitions between softirq and hardirq state, so there can be a 826 small performance impact. 827 828 If in doubt, say N here. 829 830source "kernel/Kconfig.preempt" 831 832config X86_UP_APIC 833 bool "Local APIC support on uniprocessors" 834 depends on X86_32 && !SMP && !X86_32_NON_STANDARD 835 ---help--- 836 A local APIC (Advanced Programmable Interrupt Controller) is an 837 integrated interrupt controller in the CPU. If you have a single-CPU 838 system which has a processor with a local APIC, you can say Y here to 839 enable and use it. If you say Y here even though your machine doesn't 840 have a local APIC, then the kernel will still run with no slowdown at 841 all. The local APIC supports CPU-generated self-interrupts (timer, 842 performance counters), and the NMI watchdog which detects hard 843 lockups. 844 845config X86_UP_IOAPIC 846 bool "IO-APIC support on uniprocessors" 847 depends on X86_UP_APIC 848 ---help--- 849 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 850 SMP-capable replacement for PC-style interrupt controllers. Most 851 SMP systems and many recent uniprocessor systems have one. 852 853 If you have a single-CPU system with an IO-APIC, you can say Y here 854 to use it. If you say Y here even though your machine doesn't have 855 an IO-APIC, then the kernel will still run with no slowdown at all. 856 857config X86_LOCAL_APIC 858 def_bool y 859 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC 860 861config X86_IO_APIC 862 def_bool y 863 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC 864 865config X86_VISWS_APIC 866 def_bool y 867 depends on X86_32 && X86_VISWS 868 869config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 870 bool "Reroute for broken boot IRQs" 871 depends on X86_IO_APIC 872 ---help--- 873 This option enables a workaround that fixes a source of 874 spurious interrupts. This is recommended when threaded 875 interrupt handling is used on systems where the generation of 876 superfluous "boot interrupts" cannot be disabled. 877 878 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 879 entry in the chipset's IO-APIC is masked (as, e.g. the RT 880 kernel does during interrupt handling). On chipsets where this 881 boot IRQ generation cannot be disabled, this workaround keeps 882 the original IRQ line masked so that only the equivalent "boot 883 IRQ" is delivered to the CPUs. The workaround also tells the 884 kernel to set up the IRQ handler on the boot IRQ line. In this 885 way only one interrupt is delivered to the kernel. Otherwise 886 the spurious second interrupt may cause the kernel to bring 887 down (vital) interrupt lines. 888 889 Only affects "broken" chipsets. Interrupt sharing may be 890 increased on these systems. 891 892config X86_MCE 893 bool "Machine Check / overheating reporting" 894 ---help--- 895 Machine Check support allows the processor to notify the 896 kernel if it detects a problem (e.g. overheating, data corruption). 897 The action the kernel takes depends on the severity of the problem, 898 ranging from warning messages to halting the machine. 899 900config X86_MCE_INTEL 901 def_bool y 902 prompt "Intel MCE features" 903 depends on X86_MCE && X86_LOCAL_APIC 904 ---help--- 905 Additional support for intel specific MCE features such as 906 the thermal monitor. 907 908config X86_MCE_AMD 909 def_bool y 910 prompt "AMD MCE features" 911 depends on X86_MCE && X86_LOCAL_APIC 912 ---help--- 913 Additional support for AMD specific MCE features such as 914 the DRAM Error Threshold. 915 916config X86_ANCIENT_MCE 917 bool "Support for old Pentium 5 / WinChip machine checks" 918 depends on X86_32 && X86_MCE 919 ---help--- 920 Include support for machine check handling on old Pentium 5 or WinChip 921 systems. These typically need to be enabled explicitely on the command 922 line. 923 924config X86_MCE_THRESHOLD 925 depends on X86_MCE_AMD || X86_MCE_INTEL 926 def_bool y 927 928config X86_MCE_INJECT 929 depends on X86_MCE 930 tristate "Machine check injector support" 931 ---help--- 932 Provide support for injecting machine checks for testing purposes. 933 If you don't know what a machine check is and you don't do kernel 934 QA it is safe to say n. 935 936config X86_THERMAL_VECTOR 937 def_bool y 938 depends on X86_MCE_INTEL 939 940config VM86 941 bool "Enable VM86 support" if EXPERT 942 default y 943 depends on X86_32 944 ---help--- 945 This option is required by programs like DOSEMU to run 16-bit legacy 946 code on X86 processors. It also may be needed by software like 947 XFree86 to initialize some video cards via BIOS. Disabling this 948 option saves about 6k. 949 950config TOSHIBA 951 tristate "Toshiba Laptop support" 952 depends on X86_32 953 ---help--- 954 This adds a driver to safely access the System Management Mode of 955 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 956 not work on models with a Phoenix BIOS. The System Management Mode 957 is used to set the BIOS and power saving options on Toshiba portables. 958 959 For information on utilities to make use of this driver see the 960 Toshiba Linux utilities web site at: 961 <http://www.buzzard.org.uk/toshiba/>. 962 963 Say Y if you intend to run this kernel on a Toshiba portable. 964 Say N otherwise. 965 966config I8K 967 tristate "Dell laptop support" 968 select HWMON 969 ---help--- 970 This adds a driver to safely access the System Management Mode 971 of the CPU on the Dell Inspiron 8000. The System Management Mode 972 is used to read cpu temperature and cooling fan status and to 973 control the fans on the I8K portables. 974 975 This driver has been tested only on the Inspiron 8000 but it may 976 also work with other Dell laptops. You can force loading on other 977 models by passing the parameter `force=1' to the module. Use at 978 your own risk. 979 980 For information on utilities to make use of this driver see the 981 I8K Linux utilities web site at: 982 <http://people.debian.org/~dz/i8k/> 983 984 Say Y if you intend to run this kernel on a Dell Inspiron 8000. 985 Say N otherwise. 986 987config X86_REBOOTFIXUPS 988 bool "Enable X86 board specific fixups for reboot" 989 depends on X86_32 990 ---help--- 991 This enables chipset and/or board specific fixups to be done 992 in order to get reboot to work correctly. This is only needed on 993 some combinations of hardware and BIOS. The symptom, for which 994 this config is intended, is when reboot ends with a stalled/hung 995 system. 996 997 Currently, the only fixup is for the Geode machines using 998 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 999 1000 Say Y if you want to enable the fixup. Currently, it's safe to 1001 enable this option even if you don't need it. 1002 Say N otherwise. 1003 1004config MICROCODE 1005 tristate "/dev/cpu/microcode - microcode support" 1006 select FW_LOADER 1007 ---help--- 1008 If you say Y here, you will be able to update the microcode on 1009 certain Intel and AMD processors. The Intel support is for the 1010 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, 1011 Pentium 4, Xeon etc. The AMD support is for family 0x10 and 1012 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra. 1013 You will obviously need the actual microcode binary data itself 1014 which is not shipped with the Linux kernel. 1015 1016 This option selects the general module only, you need to select 1017 at least one vendor specific module as well. 1018 1019 To compile this driver as a module, choose M here: the 1020 module will be called microcode. 1021 1022config MICROCODE_INTEL 1023 bool "Intel microcode patch loading support" 1024 depends on MICROCODE 1025 default MICROCODE 1026 select FW_LOADER 1027 ---help--- 1028 This options enables microcode patch loading support for Intel 1029 processors. 1030 1031 For latest news and information on obtaining all the required 1032 Intel ingredients for this driver, check: 1033 <http://www.urbanmyth.org/microcode/>. 1034 1035config MICROCODE_AMD 1036 bool "AMD microcode patch loading support" 1037 depends on MICROCODE 1038 select FW_LOADER 1039 ---help--- 1040 If you select this option, microcode patch loading support for AMD 1041 processors will be enabled. 1042 1043config MICROCODE_OLD_INTERFACE 1044 def_bool y 1045 depends on MICROCODE 1046 1047config X86_MSR 1048 tristate "/dev/cpu/*/msr - Model-specific register support" 1049 ---help--- 1050 This device gives privileged processes access to the x86 1051 Model-Specific Registers (MSRs). It is a character device with 1052 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1053 MSR accesses are directed to a specific CPU on multi-processor 1054 systems. 1055 1056config X86_CPUID 1057 tristate "/dev/cpu/*/cpuid - CPU information support" 1058 ---help--- 1059 This device gives processes access to the x86 CPUID instruction to 1060 be executed on a specific processor. It is a character device 1061 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1062 /dev/cpu/31/cpuid. 1063 1064choice 1065 prompt "High Memory Support" 1066 default HIGHMEM64G if X86_NUMAQ 1067 default HIGHMEM4G 1068 depends on X86_32 1069 1070config NOHIGHMEM 1071 bool "off" 1072 depends on !X86_NUMAQ 1073 ---help--- 1074 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1075 However, the address space of 32-bit x86 processors is only 4 1076 Gigabytes large. That means that, if you have a large amount of 1077 physical memory, not all of it can be "permanently mapped" by the 1078 kernel. The physical memory that's not permanently mapped is called 1079 "high memory". 1080 1081 If you are compiling a kernel which will never run on a machine with 1082 more than 1 Gigabyte total physical RAM, answer "off" here (default 1083 choice and suitable for most users). This will result in a "3GB/1GB" 1084 split: 3GB are mapped so that each process sees a 3GB virtual memory 1085 space and the remaining part of the 4GB virtual memory space is used 1086 by the kernel to permanently map as much physical memory as 1087 possible. 1088 1089 If the machine has between 1 and 4 Gigabytes physical RAM, then 1090 answer "4GB" here. 1091 1092 If more than 4 Gigabytes is used then answer "64GB" here. This 1093 selection turns Intel PAE (Physical Address Extension) mode on. 1094 PAE implements 3-level paging on IA32 processors. PAE is fully 1095 supported by Linux, PAE mode is implemented on all recent Intel 1096 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1097 then the kernel will not boot on CPUs that don't support PAE! 1098 1099 The actual amount of total physical memory will either be 1100 auto detected or can be forced by using a kernel command line option 1101 such as "mem=256M". (Try "man bootparam" or see the documentation of 1102 your boot loader (lilo or loadlin) about how to pass options to the 1103 kernel at boot time.) 1104 1105 If unsure, say "off". 1106 1107config HIGHMEM4G 1108 bool "4GB" 1109 depends on !X86_NUMAQ 1110 ---help--- 1111 Select this if you have a 32-bit processor and between 1 and 4 1112 gigabytes of physical RAM. 1113 1114config HIGHMEM64G 1115 bool "64GB" 1116 depends on !M386 && !M486 1117 select X86_PAE 1118 ---help--- 1119 Select this if you have a 32-bit processor and more than 4 1120 gigabytes of physical RAM. 1121 1122endchoice 1123 1124choice 1125 depends on EXPERIMENTAL 1126 prompt "Memory split" if EXPERT 1127 default VMSPLIT_3G 1128 depends on X86_32 1129 ---help--- 1130 Select the desired split between kernel and user memory. 1131 1132 If the address range available to the kernel is less than the 1133 physical memory installed, the remaining memory will be available 1134 as "high memory". Accessing high memory is a little more costly 1135 than low memory, as it needs to be mapped into the kernel first. 1136 Note that increasing the kernel address space limits the range 1137 available to user programs, making the address space there 1138 tighter. Selecting anything other than the default 3G/1G split 1139 will also likely make your kernel incompatible with binary-only 1140 kernel modules. 1141 1142 If you are not absolutely sure what you are doing, leave this 1143 option alone! 1144 1145 config VMSPLIT_3G 1146 bool "3G/1G user/kernel split" 1147 config VMSPLIT_3G_OPT 1148 depends on !X86_PAE 1149 bool "3G/1G user/kernel split (for full 1G low memory)" 1150 config VMSPLIT_2G 1151 bool "2G/2G user/kernel split" 1152 config VMSPLIT_2G_OPT 1153 depends on !X86_PAE 1154 bool "2G/2G user/kernel split (for full 2G low memory)" 1155 config VMSPLIT_1G 1156 bool "1G/3G user/kernel split" 1157endchoice 1158 1159config PAGE_OFFSET 1160 hex 1161 default 0xB0000000 if VMSPLIT_3G_OPT 1162 default 0x80000000 if VMSPLIT_2G 1163 default 0x78000000 if VMSPLIT_2G_OPT 1164 default 0x40000000 if VMSPLIT_1G 1165 default 0xC0000000 1166 depends on X86_32 1167 1168config HIGHMEM 1169 def_bool y 1170 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1171 1172config X86_PAE 1173 bool "PAE (Physical Address Extension) Support" 1174 depends on X86_32 && !HIGHMEM4G 1175 ---help--- 1176 PAE is required for NX support, and furthermore enables 1177 larger swapspace support for non-overcommit purposes. It 1178 has the cost of more pagetable lookup overhead, and also 1179 consumes more pagetable space per process. 1180 1181config ARCH_PHYS_ADDR_T_64BIT 1182 def_bool X86_64 || X86_PAE 1183 1184config ARCH_DMA_ADDR_T_64BIT 1185 def_bool X86_64 || HIGHMEM64G 1186 1187config DIRECT_GBPAGES 1188 bool "Enable 1GB pages for kernel pagetables" if EXPERT 1189 default y 1190 depends on X86_64 1191 ---help--- 1192 Allow the kernel linear mapping to use 1GB pages on CPUs that 1193 support it. This can improve the kernel's performance a tiny bit by 1194 reducing TLB pressure. If in doubt, say "Y". 1195 1196# Common NUMA Features 1197config NUMA 1198 bool "Numa Memory Allocation and Scheduler Support" 1199 depends on SMP 1200 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL) 1201 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP) 1202 ---help--- 1203 Enable NUMA (Non Uniform Memory Access) support. 1204 1205 The kernel will try to allocate memory used by a CPU on the 1206 local memory controller of the CPU and add some more 1207 NUMA awareness to the kernel. 1208 1209 For 64-bit this is recommended if the system is Intel Core i7 1210 (or later), AMD Opteron, or EM64T NUMA. 1211 1212 For 32-bit this is only needed on (rare) 32-bit-only platforms 1213 that support NUMA topologies, such as NUMAQ / Summit, or if you 1214 boot a 32-bit kernel on a 64-bit NUMA platform. 1215 1216 Otherwise, you should say N. 1217 1218comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI" 1219 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI) 1220 1221config AMD_NUMA 1222 def_bool y 1223 prompt "Old style AMD Opteron NUMA detection" 1224 depends on X86_64 && NUMA && PCI 1225 ---help--- 1226 Enable AMD NUMA node topology detection. You should say Y here if 1227 you have a multi processor AMD system. This uses an old method to 1228 read the NUMA configuration directly from the builtin Northbridge 1229 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1230 which also takes priority if both are compiled in. 1231 1232config X86_64_ACPI_NUMA 1233 def_bool y 1234 prompt "ACPI NUMA detection" 1235 depends on X86_64 && NUMA && ACPI && PCI 1236 select ACPI_NUMA 1237 ---help--- 1238 Enable ACPI SRAT based node topology detection. 1239 1240# Some NUMA nodes have memory ranges that span 1241# other nodes. Even though a pfn is valid and 1242# between a node's start and end pfns, it may not 1243# reside on that node. See memmap_init_zone() 1244# for details. 1245config NODES_SPAN_OTHER_NODES 1246 def_bool y 1247 depends on X86_64_ACPI_NUMA 1248 1249config NUMA_EMU 1250 bool "NUMA emulation" 1251 depends on NUMA 1252 ---help--- 1253 Enable NUMA emulation. A flat machine will be split 1254 into virtual nodes when booted with "numa=fake=N", where N is the 1255 number of nodes. This is only useful for debugging. 1256 1257config NODES_SHIFT 1258 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1259 range 1 10 1260 default "10" if MAXSMP 1261 default "6" if X86_64 1262 default "4" if X86_NUMAQ 1263 default "3" 1264 depends on NEED_MULTIPLE_NODES 1265 ---help--- 1266 Specify the maximum number of NUMA Nodes available on the target 1267 system. Increases memory reserved to accommodate various tables. 1268 1269config HAVE_ARCH_BOOTMEM 1270 def_bool y 1271 depends on X86_32 && NUMA 1272 1273config ARCH_HAVE_MEMORY_PRESENT 1274 def_bool y 1275 depends on X86_32 && DISCONTIGMEM 1276 1277config NEED_NODE_MEMMAP_SIZE 1278 def_bool y 1279 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1280 1281config ARCH_FLATMEM_ENABLE 1282 def_bool y 1283 depends on X86_32 && !NUMA 1284 1285config ARCH_DISCONTIGMEM_ENABLE 1286 def_bool y 1287 depends on NUMA && X86_32 1288 1289config ARCH_DISCONTIGMEM_DEFAULT 1290 def_bool y 1291 depends on NUMA && X86_32 1292 1293config ARCH_SPARSEMEM_ENABLE 1294 def_bool y 1295 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD 1296 select SPARSEMEM_STATIC if X86_32 1297 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1298 1299config ARCH_SPARSEMEM_DEFAULT 1300 def_bool y 1301 depends on X86_64 1302 1303config ARCH_SELECT_MEMORY_MODEL 1304 def_bool y 1305 depends on ARCH_SPARSEMEM_ENABLE 1306 1307config ARCH_MEMORY_PROBE 1308 def_bool X86_64 1309 depends on MEMORY_HOTPLUG 1310 1311config ARCH_PROC_KCORE_TEXT 1312 def_bool y 1313 depends on X86_64 && PROC_KCORE 1314 1315config ILLEGAL_POINTER_VALUE 1316 hex 1317 default 0 if X86_32 1318 default 0xdead000000000000 if X86_64 1319 1320source "mm/Kconfig" 1321 1322config HIGHPTE 1323 bool "Allocate 3rd-level pagetables from highmem" 1324 depends on HIGHMEM 1325 ---help--- 1326 The VM uses one page table entry for each page of physical memory. 1327 For systems with a lot of RAM, this can be wasteful of precious 1328 low memory. Setting this option will put user-space page table 1329 entries in high memory. 1330 1331config X86_CHECK_BIOS_CORRUPTION 1332 bool "Check for low memory corruption" 1333 ---help--- 1334 Periodically check for memory corruption in low memory, which 1335 is suspected to be caused by BIOS. Even when enabled in the 1336 configuration, it is disabled at runtime. Enable it by 1337 setting "memory_corruption_check=1" on the kernel command 1338 line. By default it scans the low 64k of memory every 60 1339 seconds; see the memory_corruption_check_size and 1340 memory_corruption_check_period parameters in 1341 Documentation/kernel-parameters.txt to adjust this. 1342 1343 When enabled with the default parameters, this option has 1344 almost no overhead, as it reserves a relatively small amount 1345 of memory and scans it infrequently. It both detects corruption 1346 and prevents it from affecting the running system. 1347 1348 It is, however, intended as a diagnostic tool; if repeatable 1349 BIOS-originated corruption always affects the same memory, 1350 you can use memmap= to prevent the kernel from using that 1351 memory. 1352 1353config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1354 bool "Set the default setting of memory_corruption_check" 1355 depends on X86_CHECK_BIOS_CORRUPTION 1356 default y 1357 ---help--- 1358 Set whether the default state of memory_corruption_check is 1359 on or off. 1360 1361config X86_RESERVE_LOW 1362 int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1363 default 64 1364 range 4 640 1365 ---help--- 1366 Specify the amount of low memory to reserve for the BIOS. 1367 1368 The first page contains BIOS data structures that the kernel 1369 must not use, so that page must always be reserved. 1370 1371 By default we reserve the first 64K of physical RAM, as a 1372 number of BIOSes are known to corrupt that memory range 1373 during events such as suspend/resume or monitor cable 1374 insertion, so it must not be used by the kernel. 1375 1376 You can set this to 4 if you are absolutely sure that you 1377 trust the BIOS to get all its memory reservations and usages 1378 right. If you know your BIOS have problems beyond the 1379 default 64K area, you can set this to 640 to avoid using the 1380 entire low memory range. 1381 1382 If you have doubts about the BIOS (e.g. suspend/resume does 1383 not work or there's kernel crashes after certain hardware 1384 hotplug events) then you might want to enable 1385 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1386 typical corruption patterns. 1387 1388 Leave this to the default value of 64 if you are unsure. 1389 1390config MATH_EMULATION 1391 bool 1392 prompt "Math emulation" if X86_32 1393 ---help--- 1394 Linux can emulate a math coprocessor (used for floating point 1395 operations) if you don't have one. 486DX and Pentium processors have 1396 a math coprocessor built in, 486SX and 386 do not, unless you added 1397 a 487DX or 387, respectively. (The messages during boot time can 1398 give you some hints here ["man dmesg"].) Everyone needs either a 1399 coprocessor or this emulation. 1400 1401 If you don't have a math coprocessor, you need to say Y here; if you 1402 say Y here even though you have a coprocessor, the coprocessor will 1403 be used nevertheless. (This behavior can be changed with the kernel 1404 command line option "no387", which comes handy if your coprocessor 1405 is broken. Try "man bootparam" or see the documentation of your boot 1406 loader (lilo or loadlin) about how to pass options to the kernel at 1407 boot time.) This means that it is a good idea to say Y here if you 1408 intend to use this kernel on different machines. 1409 1410 More information about the internals of the Linux math coprocessor 1411 emulation can be found in <file:arch/x86/math-emu/README>. 1412 1413 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1414 kernel, it won't hurt. 1415 1416config MTRR 1417 def_bool y 1418 prompt "MTRR (Memory Type Range Register) support" if EXPERT 1419 ---help--- 1420 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1421 the Memory Type Range Registers (MTRRs) may be used to control 1422 processor access to memory ranges. This is most useful if you have 1423 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1424 allows bus write transfers to be combined into a larger transfer 1425 before bursting over the PCI/AGP bus. This can increase performance 1426 of image write operations 2.5 times or more. Saying Y here creates a 1427 /proc/mtrr file which may be used to manipulate your processor's 1428 MTRRs. Typically the X server should use this. 1429 1430 This code has a reasonably generic interface so that similar 1431 control registers on other processors can be easily supported 1432 as well: 1433 1434 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1435 Registers (ARRs) which provide a similar functionality to MTRRs. For 1436 these, the ARRs are used to emulate the MTRRs. 1437 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1438 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1439 write-combining. All of these processors are supported by this code 1440 and it makes sense to say Y here if you have one of them. 1441 1442 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1443 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1444 can lead to all sorts of problems, so it's good to say Y here. 1445 1446 You can safely say Y even if your machine doesn't have MTRRs, you'll 1447 just add about 9 KB to your kernel. 1448 1449 See <file:Documentation/x86/mtrr.txt> for more information. 1450 1451config MTRR_SANITIZER 1452 def_bool y 1453 prompt "MTRR cleanup support" 1454 depends on MTRR 1455 ---help--- 1456 Convert MTRR layout from continuous to discrete, so X drivers can 1457 add writeback entries. 1458 1459 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1460 The largest mtrr entry size for a continuous block can be set with 1461 mtrr_chunk_size. 1462 1463 If unsure, say Y. 1464 1465config MTRR_SANITIZER_ENABLE_DEFAULT 1466 int "MTRR cleanup enable value (0-1)" 1467 range 0 1 1468 default "0" 1469 depends on MTRR_SANITIZER 1470 ---help--- 1471 Enable mtrr cleanup default value 1472 1473config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1474 int "MTRR cleanup spare reg num (0-7)" 1475 range 0 7 1476 default "1" 1477 depends on MTRR_SANITIZER 1478 ---help--- 1479 mtrr cleanup spare entries default, it can be changed via 1480 mtrr_spare_reg_nr=N on the kernel command line. 1481 1482config X86_PAT 1483 def_bool y 1484 prompt "x86 PAT support" if EXPERT 1485 depends on MTRR 1486 ---help--- 1487 Use PAT attributes to setup page level cache control. 1488 1489 PATs are the modern equivalents of MTRRs and are much more 1490 flexible than MTRRs. 1491 1492 Say N here if you see bootup problems (boot crash, boot hang, 1493 spontaneous reboots) or a non-working video driver. 1494 1495 If unsure, say Y. 1496 1497config ARCH_USES_PG_UNCACHED 1498 def_bool y 1499 depends on X86_PAT 1500 1501config ARCH_RANDOM 1502 def_bool y 1503 prompt "x86 architectural random number generator" if EXPERT 1504 ---help--- 1505 Enable the x86 architectural RDRAND instruction 1506 (Intel Bull Mountain technology) to generate random numbers. 1507 If supported, this is a high bandwidth, cryptographically 1508 secure hardware random number generator. 1509 1510config EFI 1511 bool "EFI runtime service support" 1512 depends on ACPI 1513 ---help--- 1514 This enables the kernel to use EFI runtime services that are 1515 available (such as the EFI variable services). 1516 1517 This option is only useful on systems that have EFI firmware. 1518 In addition, you should use the latest ELILO loader available 1519 at <http://elilo.sourceforge.net> in order to take advantage 1520 of EFI runtime services. However, even with this option, the 1521 resultant kernel should continue to boot on existing non-EFI 1522 platforms. 1523 1524config EFI_STUB 1525 bool "EFI stub support" 1526 depends on EFI 1527 ---help--- 1528 This kernel feature allows a bzImage to be loaded directly 1529 by EFI firmware without the use of a bootloader. 1530 1531config SECCOMP 1532 def_bool y 1533 prompt "Enable seccomp to safely compute untrusted bytecode" 1534 ---help--- 1535 This kernel feature is useful for number crunching applications 1536 that may need to compute untrusted bytecode during their 1537 execution. By using pipes or other transports made available to 1538 the process as file descriptors supporting the read/write 1539 syscalls, it's possible to isolate those applications in 1540 their own address space using seccomp. Once seccomp is 1541 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1542 and the task is only allowed to execute a few safe syscalls 1543 defined by each seccomp mode. 1544 1545 If unsure, say Y. Only embedded should say N here. 1546 1547config CC_STACKPROTECTOR 1548 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)" 1549 ---help--- 1550 This option turns on the -fstack-protector GCC feature. This 1551 feature puts, at the beginning of functions, a canary value on 1552 the stack just before the return address, and validates 1553 the value just before actually returning. Stack based buffer 1554 overflows (that need to overwrite this return address) now also 1555 overwrite the canary, which gets detected and the attack is then 1556 neutralized via a kernel panic. 1557 1558 This feature requires gcc version 4.2 or above, or a distribution 1559 gcc with the feature backported. Older versions are automatically 1560 detected and for those versions, this configuration option is 1561 ignored. (and a warning is printed during bootup) 1562 1563source kernel/Kconfig.hz 1564 1565config KEXEC 1566 bool "kexec system call" 1567 ---help--- 1568 kexec is a system call that implements the ability to shutdown your 1569 current kernel, and to start another kernel. It is like a reboot 1570 but it is independent of the system firmware. And like a reboot 1571 you can start any kernel with it, not just Linux. 1572 1573 The name comes from the similarity to the exec system call. 1574 1575 It is an ongoing process to be certain the hardware in a machine 1576 is properly shutdown, so do not be surprised if this code does not 1577 initially work for you. It may help to enable device hotplugging 1578 support. As of this writing the exact hardware interface is 1579 strongly in flux, so no good recommendation can be made. 1580 1581config CRASH_DUMP 1582 bool "kernel crash dumps" 1583 depends on X86_64 || (X86_32 && HIGHMEM) 1584 ---help--- 1585 Generate crash dump after being started by kexec. 1586 This should be normally only set in special crash dump kernels 1587 which are loaded in the main kernel with kexec-tools into 1588 a specially reserved region and then later executed after 1589 a crash by kdump/kexec. The crash dump kernel must be compiled 1590 to a memory address not used by the main kernel or BIOS using 1591 PHYSICAL_START, or it must be built as a relocatable image 1592 (CONFIG_RELOCATABLE=y). 1593 For more details see Documentation/kdump/kdump.txt 1594 1595config KEXEC_JUMP 1596 bool "kexec jump (EXPERIMENTAL)" 1597 depends on EXPERIMENTAL 1598 depends on KEXEC && HIBERNATION 1599 ---help--- 1600 Jump between original kernel and kexeced kernel and invoke 1601 code in physical address mode via KEXEC 1602 1603config PHYSICAL_START 1604 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1605 default "0x1000000" 1606 ---help--- 1607 This gives the physical address where the kernel is loaded. 1608 1609 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1610 bzImage will decompress itself to above physical address and 1611 run from there. Otherwise, bzImage will run from the address where 1612 it has been loaded by the boot loader and will ignore above physical 1613 address. 1614 1615 In normal kdump cases one does not have to set/change this option 1616 as now bzImage can be compiled as a completely relocatable image 1617 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1618 address. This option is mainly useful for the folks who don't want 1619 to use a bzImage for capturing the crash dump and want to use a 1620 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1621 to be specifically compiled to run from a specific memory area 1622 (normally a reserved region) and this option comes handy. 1623 1624 So if you are using bzImage for capturing the crash dump, 1625 leave the value here unchanged to 0x1000000 and set 1626 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1627 for capturing the crash dump change this value to start of 1628 the reserved region. In other words, it can be set based on 1629 the "X" value as specified in the "crashkernel=YM@XM" 1630 command line boot parameter passed to the panic-ed 1631 kernel. Please take a look at Documentation/kdump/kdump.txt 1632 for more details about crash dumps. 1633 1634 Usage of bzImage for capturing the crash dump is recommended as 1635 one does not have to build two kernels. Same kernel can be used 1636 as production kernel and capture kernel. Above option should have 1637 gone away after relocatable bzImage support is introduced. But it 1638 is present because there are users out there who continue to use 1639 vmlinux for dump capture. This option should go away down the 1640 line. 1641 1642 Don't change this unless you know what you are doing. 1643 1644config RELOCATABLE 1645 bool "Build a relocatable kernel" 1646 default y 1647 ---help--- 1648 This builds a kernel image that retains relocation information 1649 so it can be loaded someplace besides the default 1MB. 1650 The relocations tend to make the kernel binary about 10% larger, 1651 but are discarded at runtime. 1652 1653 One use is for the kexec on panic case where the recovery kernel 1654 must live at a different physical address than the primary 1655 kernel. 1656 1657 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1658 it has been loaded at and the compile time physical address 1659 (CONFIG_PHYSICAL_START) is ignored. 1660 1661# Relocation on x86-32 needs some additional build support 1662config X86_NEED_RELOCS 1663 def_bool y 1664 depends on X86_32 && RELOCATABLE 1665 1666config PHYSICAL_ALIGN 1667 hex "Alignment value to which kernel should be aligned" if X86_32 1668 default "0x1000000" 1669 range 0x2000 0x1000000 1670 ---help--- 1671 This value puts the alignment restrictions on physical address 1672 where kernel is loaded and run from. Kernel is compiled for an 1673 address which meets above alignment restriction. 1674 1675 If bootloader loads the kernel at a non-aligned address and 1676 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1677 address aligned to above value and run from there. 1678 1679 If bootloader loads the kernel at a non-aligned address and 1680 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1681 load address and decompress itself to the address it has been 1682 compiled for and run from there. The address for which kernel is 1683 compiled already meets above alignment restrictions. Hence the 1684 end result is that kernel runs from a physical address meeting 1685 above alignment restrictions. 1686 1687 Don't change this unless you know what you are doing. 1688 1689config HOTPLUG_CPU 1690 bool "Support for hot-pluggable CPUs" 1691 depends on SMP && HOTPLUG 1692 ---help--- 1693 Say Y here to allow turning CPUs off and on. CPUs can be 1694 controlled through /sys/devices/system/cpu. 1695 ( Note: power management support will enable this option 1696 automatically on SMP systems. ) 1697 Say N if you want to disable CPU hotplug. 1698 1699config COMPAT_VDSO 1700 def_bool y 1701 prompt "Compat VDSO support" 1702 depends on X86_32 || IA32_EMULATION 1703 ---help--- 1704 Map the 32-bit VDSO to the predictable old-style address too. 1705 1706 Say N here if you are running a sufficiently recent glibc 1707 version (2.3.3 or later), to remove the high-mapped 1708 VDSO mapping and to exclusively use the randomized VDSO. 1709 1710 If unsure, say Y. 1711 1712config CMDLINE_BOOL 1713 bool "Built-in kernel command line" 1714 ---help--- 1715 Allow for specifying boot arguments to the kernel at 1716 build time. On some systems (e.g. embedded ones), it is 1717 necessary or convenient to provide some or all of the 1718 kernel boot arguments with the kernel itself (that is, 1719 to not rely on the boot loader to provide them.) 1720 1721 To compile command line arguments into the kernel, 1722 set this option to 'Y', then fill in the 1723 the boot arguments in CONFIG_CMDLINE. 1724 1725 Systems with fully functional boot loaders (i.e. non-embedded) 1726 should leave this option set to 'N'. 1727 1728config CMDLINE 1729 string "Built-in kernel command string" 1730 depends on CMDLINE_BOOL 1731 default "" 1732 ---help--- 1733 Enter arguments here that should be compiled into the kernel 1734 image and used at boot time. If the boot loader provides a 1735 command line at boot time, it is appended to this string to 1736 form the full kernel command line, when the system boots. 1737 1738 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 1739 change this behavior. 1740 1741 In most cases, the command line (whether built-in or provided 1742 by the boot loader) should specify the device for the root 1743 file system. 1744 1745config CMDLINE_OVERRIDE 1746 bool "Built-in command line overrides boot loader arguments" 1747 depends on CMDLINE_BOOL 1748 ---help--- 1749 Set this option to 'Y' to have the kernel ignore the boot loader 1750 command line, and use ONLY the built-in command line. 1751 1752 This is used to work around broken boot loaders. This should 1753 be set to 'N' under normal conditions. 1754 1755endmenu 1756 1757config ARCH_ENABLE_MEMORY_HOTPLUG 1758 def_bool y 1759 depends on X86_64 || (X86_32 && HIGHMEM) 1760 1761config ARCH_ENABLE_MEMORY_HOTREMOVE 1762 def_bool y 1763 depends on MEMORY_HOTPLUG 1764 1765config USE_PERCPU_NUMA_NODE_ID 1766 def_bool y 1767 depends on NUMA 1768 1769menu "Power management and ACPI options" 1770 1771config ARCH_HIBERNATION_HEADER 1772 def_bool y 1773 depends on X86_64 && HIBERNATION 1774 1775source "kernel/power/Kconfig" 1776 1777source "drivers/acpi/Kconfig" 1778 1779source "drivers/sfi/Kconfig" 1780 1781config X86_APM_BOOT 1782 def_bool y 1783 depends on APM 1784 1785menuconfig APM 1786 tristate "APM (Advanced Power Management) BIOS support" 1787 depends on X86_32 && PM_SLEEP 1788 ---help--- 1789 APM is a BIOS specification for saving power using several different 1790 techniques. This is mostly useful for battery powered laptops with 1791 APM compliant BIOSes. If you say Y here, the system time will be 1792 reset after a RESUME operation, the /proc/apm device will provide 1793 battery status information, and user-space programs will receive 1794 notification of APM "events" (e.g. battery status change). 1795 1796 If you select "Y" here, you can disable actual use of the APM 1797 BIOS by passing the "apm=off" option to the kernel at boot time. 1798 1799 Note that the APM support is almost completely disabled for 1800 machines with more than one CPU. 1801 1802 In order to use APM, you will need supporting software. For location 1803 and more information, read <file:Documentation/power/apm-acpi.txt> 1804 and the Battery Powered Linux mini-HOWTO, available from 1805 <http://www.tldp.org/docs.html#howto>. 1806 1807 This driver does not spin down disk drives (see the hdparm(8) 1808 manpage ("man 8 hdparm") for that), and it doesn't turn off 1809 VESA-compliant "green" monitors. 1810 1811 This driver does not support the TI 4000M TravelMate and the ACER 1812 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1813 desktop machines also don't have compliant BIOSes, and this driver 1814 may cause those machines to panic during the boot phase. 1815 1816 Generally, if you don't have a battery in your machine, there isn't 1817 much point in using this driver and you should say N. If you get 1818 random kernel OOPSes or reboots that don't seem to be related to 1819 anything, try disabling/enabling this option (or disabling/enabling 1820 APM in your BIOS). 1821 1822 Some other things you should try when experiencing seemingly random, 1823 "weird" problems: 1824 1825 1) make sure that you have enough swap space and that it is 1826 enabled. 1827 2) pass the "no-hlt" option to the kernel 1828 3) switch on floating point emulation in the kernel and pass 1829 the "no387" option to the kernel 1830 4) pass the "floppy=nodma" option to the kernel 1831 5) pass the "mem=4M" option to the kernel (thereby disabling 1832 all but the first 4 MB of RAM) 1833 6) make sure that the CPU is not over clocked. 1834 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1835 8) disable the cache from your BIOS settings 1836 9) install a fan for the video card or exchange video RAM 1837 10) install a better fan for the CPU 1838 11) exchange RAM chips 1839 12) exchange the motherboard. 1840 1841 To compile this driver as a module, choose M here: the 1842 module will be called apm. 1843 1844if APM 1845 1846config APM_IGNORE_USER_SUSPEND 1847 bool "Ignore USER SUSPEND" 1848 ---help--- 1849 This option will ignore USER SUSPEND requests. On machines with a 1850 compliant APM BIOS, you want to say N. However, on the NEC Versa M 1851 series notebooks, it is necessary to say Y because of a BIOS bug. 1852 1853config APM_DO_ENABLE 1854 bool "Enable PM at boot time" 1855 ---help--- 1856 Enable APM features at boot time. From page 36 of the APM BIOS 1857 specification: "When disabled, the APM BIOS does not automatically 1858 power manage devices, enter the Standby State, enter the Suspend 1859 State, or take power saving steps in response to CPU Idle calls." 1860 This driver will make CPU Idle calls when Linux is idle (unless this 1861 feature is turned off -- see "Do CPU IDLE calls", below). This 1862 should always save battery power, but more complicated APM features 1863 will be dependent on your BIOS implementation. You may need to turn 1864 this option off if your computer hangs at boot time when using APM 1865 support, or if it beeps continuously instead of suspending. Turn 1866 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1867 T400CDT. This is off by default since most machines do fine without 1868 this feature. 1869 1870config APM_CPU_IDLE 1871 bool "Make CPU Idle calls when idle" 1872 ---help--- 1873 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 1874 On some machines, this can activate improved power savings, such as 1875 a slowed CPU clock rate, when the machine is idle. These idle calls 1876 are made after the idle loop has run for some length of time (e.g., 1877 333 mS). On some machines, this will cause a hang at boot time or 1878 whenever the CPU becomes idle. (On machines with more than one CPU, 1879 this option does nothing.) 1880 1881config APM_DISPLAY_BLANK 1882 bool "Enable console blanking using APM" 1883 ---help--- 1884 Enable console blanking using the APM. Some laptops can use this to 1885 turn off the LCD backlight when the screen blanker of the Linux 1886 virtual console blanks the screen. Note that this is only used by 1887 the virtual console screen blanker, and won't turn off the backlight 1888 when using the X Window system. This also doesn't have anything to 1889 do with your VESA-compliant power-saving monitor. Further, this 1890 option doesn't work for all laptops -- it might not turn off your 1891 backlight at all, or it might print a lot of errors to the console, 1892 especially if you are using gpm. 1893 1894config APM_ALLOW_INTS 1895 bool "Allow interrupts during APM BIOS calls" 1896 ---help--- 1897 Normally we disable external interrupts while we are making calls to 1898 the APM BIOS as a measure to lessen the effects of a badly behaving 1899 BIOS implementation. The BIOS should reenable interrupts if it 1900 needs to. Unfortunately, some BIOSes do not -- especially those in 1901 many of the newer IBM Thinkpads. If you experience hangs when you 1902 suspend, try setting this to Y. Otherwise, say N. 1903 1904endif # APM 1905 1906source "drivers/cpufreq/Kconfig" 1907 1908source "drivers/cpuidle/Kconfig" 1909 1910source "drivers/idle/Kconfig" 1911 1912endmenu 1913 1914 1915menu "Bus options (PCI etc.)" 1916 1917config PCI 1918 bool "PCI support" 1919 default y 1920 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC) 1921 ---help--- 1922 Find out whether you have a PCI motherboard. PCI is the name of a 1923 bus system, i.e. the way the CPU talks to the other stuff inside 1924 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 1925 VESA. If you have PCI, say Y, otherwise N. 1926 1927choice 1928 prompt "PCI access mode" 1929 depends on X86_32 && PCI 1930 default PCI_GOANY 1931 ---help--- 1932 On PCI systems, the BIOS can be used to detect the PCI devices and 1933 determine their configuration. However, some old PCI motherboards 1934 have BIOS bugs and may crash if this is done. Also, some embedded 1935 PCI-based systems don't have any BIOS at all. Linux can also try to 1936 detect the PCI hardware directly without using the BIOS. 1937 1938 With this option, you can specify how Linux should detect the 1939 PCI devices. If you choose "BIOS", the BIOS will be used, 1940 if you choose "Direct", the BIOS won't be used, and if you 1941 choose "MMConfig", then PCI Express MMCONFIG will be used. 1942 If you choose "Any", the kernel will try MMCONFIG, then the 1943 direct access method and falls back to the BIOS if that doesn't 1944 work. If unsure, go with the default, which is "Any". 1945 1946config PCI_GOBIOS 1947 bool "BIOS" 1948 1949config PCI_GOMMCONFIG 1950 bool "MMConfig" 1951 1952config PCI_GODIRECT 1953 bool "Direct" 1954 1955config PCI_GOOLPC 1956 bool "OLPC XO-1" 1957 depends on OLPC 1958 1959config PCI_GOANY 1960 bool "Any" 1961 1962endchoice 1963 1964config PCI_BIOS 1965 def_bool y 1966 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 1967 1968# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 1969config PCI_DIRECT 1970 def_bool y 1971 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 1972 1973config PCI_MMCONFIG 1974 def_bool y 1975 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 1976 1977config PCI_OLPC 1978 def_bool y 1979 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 1980 1981config PCI_XEN 1982 def_bool y 1983 depends on PCI && XEN 1984 select SWIOTLB_XEN 1985 1986config PCI_DOMAINS 1987 def_bool y 1988 depends on PCI 1989 1990config PCI_MMCONFIG 1991 bool "Support mmconfig PCI config space access" 1992 depends on X86_64 && PCI && ACPI 1993 1994config PCI_CNB20LE_QUIRK 1995 bool "Read CNB20LE Host Bridge Windows" if EXPERT 1996 default n 1997 depends on PCI && EXPERIMENTAL 1998 help 1999 Read the PCI windows out of the CNB20LE host bridge. This allows 2000 PCI hotplug to work on systems with the CNB20LE chipset which do 2001 not have ACPI. 2002 2003 There's no public spec for this chipset, and this functionality 2004 is known to be incomplete. 2005 2006 You should say N unless you know you need this. 2007 2008source "drivers/pci/pcie/Kconfig" 2009 2010source "drivers/pci/Kconfig" 2011 2012# x86_64 have no ISA slots, but can have ISA-style DMA. 2013config ISA_DMA_API 2014 bool "ISA-style DMA support" if (X86_64 && EXPERT) 2015 default y 2016 help 2017 Enables ISA-style DMA support for devices requiring such controllers. 2018 If unsure, say Y. 2019 2020if X86_32 2021 2022config ISA 2023 bool "ISA support" 2024 ---help--- 2025 Find out whether you have ISA slots on your motherboard. ISA is the 2026 name of a bus system, i.e. the way the CPU talks to the other stuff 2027 inside your box. Other bus systems are PCI, EISA, MicroChannel 2028 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2029 newer boards don't support it. If you have ISA, say Y, otherwise N. 2030 2031config EISA 2032 bool "EISA support" 2033 depends on ISA 2034 ---help--- 2035 The Extended Industry Standard Architecture (EISA) bus was 2036 developed as an open alternative to the IBM MicroChannel bus. 2037 2038 The EISA bus provided some of the features of the IBM MicroChannel 2039 bus while maintaining backward compatibility with cards made for 2040 the older ISA bus. The EISA bus saw limited use between 1988 and 2041 1995 when it was made obsolete by the PCI bus. 2042 2043 Say Y here if you are building a kernel for an EISA-based machine. 2044 2045 Otherwise, say N. 2046 2047source "drivers/eisa/Kconfig" 2048 2049config MCA 2050 bool "MCA support" 2051 ---help--- 2052 MicroChannel Architecture is found in some IBM PS/2 machines and 2053 laptops. It is a bus system similar to PCI or ISA. See 2054 <file:Documentation/mca.txt> (and especially the web page given 2055 there) before attempting to build an MCA bus kernel. 2056 2057source "drivers/mca/Kconfig" 2058 2059config SCx200 2060 tristate "NatSemi SCx200 support" 2061 ---help--- 2062 This provides basic support for National Semiconductor's 2063 (now AMD's) Geode processors. The driver probes for the 2064 PCI-IDs of several on-chip devices, so its a good dependency 2065 for other scx200_* drivers. 2066 2067 If compiled as a module, the driver is named scx200. 2068 2069config SCx200HR_TIMER 2070 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2071 depends on SCx200 2072 default y 2073 ---help--- 2074 This driver provides a clocksource built upon the on-chip 2075 27MHz high-resolution timer. Its also a workaround for 2076 NSC Geode SC-1100's buggy TSC, which loses time when the 2077 processor goes idle (as is done by the scheduler). The 2078 other workaround is idle=poll boot option. 2079 2080config OLPC 2081 bool "One Laptop Per Child support" 2082 depends on !X86_PAE 2083 select GPIOLIB 2084 select OF 2085 select OF_PROMTREE 2086 select IRQ_DOMAIN 2087 ---help--- 2088 Add support for detecting the unique features of the OLPC 2089 XO hardware. 2090 2091config OLPC_XO1_PM 2092 bool "OLPC XO-1 Power Management" 2093 depends on OLPC && MFD_CS5535 && PM_SLEEP 2094 select MFD_CORE 2095 ---help--- 2096 Add support for poweroff and suspend of the OLPC XO-1 laptop. 2097 2098config OLPC_XO1_RTC 2099 bool "OLPC XO-1 Real Time Clock" 2100 depends on OLPC_XO1_PM && RTC_DRV_CMOS 2101 ---help--- 2102 Add support for the XO-1 real time clock, which can be used as a 2103 programmable wakeup source. 2104 2105config OLPC_XO1_SCI 2106 bool "OLPC XO-1 SCI extras" 2107 depends on OLPC && OLPC_XO1_PM 2108 select POWER_SUPPLY 2109 select GPIO_CS5535 2110 select MFD_CORE 2111 ---help--- 2112 Add support for SCI-based features of the OLPC XO-1 laptop: 2113 - EC-driven system wakeups 2114 - Power button 2115 - Ebook switch 2116 - Lid switch 2117 - AC adapter status updates 2118 - Battery status updates 2119 2120config OLPC_XO15_SCI 2121 bool "OLPC XO-1.5 SCI extras" 2122 depends on OLPC && ACPI 2123 select POWER_SUPPLY 2124 ---help--- 2125 Add support for SCI-based features of the OLPC XO-1.5 laptop: 2126 - EC-driven system wakeups 2127 - AC adapter status updates 2128 - Battery status updates 2129 2130config ALIX 2131 bool "PCEngines ALIX System Support (LED setup)" 2132 select GPIOLIB 2133 ---help--- 2134 This option enables system support for the PCEngines ALIX. 2135 At present this just sets up LEDs for GPIO control on 2136 ALIX2/3/6 boards. However, other system specific setup should 2137 get added here. 2138 2139 Note: You must still enable the drivers for GPIO and LED support 2140 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2141 2142 Note: You have to set alix.force=1 for boards with Award BIOS. 2143 2144config NET5501 2145 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2146 select GPIOLIB 2147 ---help--- 2148 This option enables system support for the Soekris Engineering net5501. 2149 2150config GEOS 2151 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 2152 select GPIOLIB 2153 depends on DMI 2154 ---help--- 2155 This option enables system support for the Traverse Technologies GEOS. 2156 2157endif # X86_32 2158 2159config AMD_NB 2160 def_bool y 2161 depends on CPU_SUP_AMD && PCI 2162 2163source "drivers/pcmcia/Kconfig" 2164 2165source "drivers/pci/hotplug/Kconfig" 2166 2167config RAPIDIO 2168 bool "RapidIO support" 2169 depends on PCI 2170 default n 2171 help 2172 If you say Y here, the kernel will include drivers and 2173 infrastructure code to support RapidIO interconnect devices. 2174 2175source "drivers/rapidio/Kconfig" 2176 2177endmenu 2178 2179 2180menu "Executable file formats / Emulations" 2181 2182source "fs/Kconfig.binfmt" 2183 2184config IA32_EMULATION 2185 bool "IA32 Emulation" 2186 depends on X86_64 2187 select COMPAT_BINFMT_ELF 2188 ---help--- 2189 Include code to run legacy 32-bit programs under a 2190 64-bit kernel. You should likely turn this on, unless you're 2191 100% sure that you don't have any 32-bit programs left. 2192 2193config IA32_AOUT 2194 tristate "IA32 a.out support" 2195 depends on IA32_EMULATION 2196 ---help--- 2197 Support old a.out binaries in the 32bit emulation. 2198 2199config X86_X32 2200 bool "x32 ABI for 64-bit mode (EXPERIMENTAL)" 2201 depends on X86_64 && IA32_EMULATION && EXPERIMENTAL 2202 ---help--- 2203 Include code to run binaries for the x32 native 32-bit ABI 2204 for 64-bit processors. An x32 process gets access to the 2205 full 64-bit register file and wide data path while leaving 2206 pointers at 32 bits for smaller memory footprint. 2207 2208 You will need a recent binutils (2.22 or later) with 2209 elf32_x86_64 support enabled to compile a kernel with this 2210 option set. 2211 2212config COMPAT 2213 def_bool y 2214 depends on IA32_EMULATION || X86_X32 2215 select ARCH_WANT_OLD_COMPAT_IPC 2216 2217config COMPAT_FOR_U64_ALIGNMENT 2218 def_bool COMPAT 2219 depends on X86_64 2220 2221config SYSVIPC_COMPAT 2222 def_bool y 2223 depends on COMPAT && SYSVIPC 2224 2225config KEYS_COMPAT 2226 bool 2227 depends on COMPAT && KEYS 2228 default y 2229 2230endmenu 2231 2232 2233config HAVE_ATOMIC_IOMAP 2234 def_bool y 2235 depends on X86_32 2236 2237config HAVE_TEXT_POKE_SMP 2238 bool 2239 select STOP_MACHINE if SMP 2240 2241source "net/Kconfig" 2242 2243source "drivers/Kconfig" 2244 2245source "drivers/firmware/Kconfig" 2246 2247source "fs/Kconfig" 2248 2249source "arch/x86/Kconfig.debug" 2250 2251source "security/Kconfig" 2252 2253source "crypto/Kconfig" 2254 2255source "arch/x86/kvm/Kconfig" 2256 2257source "lib/Kconfig" 2258