1# Select 32 or 64 bit 2config 64BIT 3 bool "64-bit kernel" if ARCH = "x86" 4 default ARCH != "i386" 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 y 11 depends on !64BIT 12 select CLKSRC_I8253 13 select HAVE_UID16 14 15config X86_64 16 def_bool y 17 depends on 64BIT 18 select X86_DEV_DMA_OPS 19 select ARCH_USE_CMPXCHG_LOCKREF 20 21### Arch settings 22config X86 23 def_bool y 24 select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS 25 select ARCH_MIGHT_HAVE_PC_PARPORT 26 select ARCH_MIGHT_HAVE_PC_SERIO 27 select HAVE_AOUT if X86_32 28 select HAVE_UNSTABLE_SCHED_CLOCK 29 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 30 select ARCH_SUPPORTS_INT128 if X86_64 31 select ARCH_WANTS_PROT_NUMA_PROT_NONE 32 select HAVE_IDE 33 select HAVE_OPROFILE 34 select HAVE_PCSPKR_PLATFORM 35 select HAVE_PERF_EVENTS 36 select HAVE_IOREMAP_PROT 37 select HAVE_KPROBES 38 select HAVE_MEMBLOCK 39 select HAVE_MEMBLOCK_NODE_MAP 40 select ARCH_DISCARD_MEMBLOCK 41 select ARCH_WANT_OPTIONAL_GPIOLIB 42 select ARCH_WANT_FRAME_POINTERS 43 select HAVE_DMA_ATTRS 44 select HAVE_DMA_CONTIGUOUS 45 select HAVE_KRETPROBES 46 select GENERIC_EARLY_IOREMAP 47 select HAVE_OPTPROBES 48 select HAVE_KPROBES_ON_FTRACE 49 select HAVE_FTRACE_MCOUNT_RECORD 50 select HAVE_FENTRY if X86_64 51 select HAVE_C_RECORDMCOUNT 52 select HAVE_DYNAMIC_FTRACE 53 select HAVE_DYNAMIC_FTRACE_WITH_REGS 54 select HAVE_FUNCTION_TRACER 55 select HAVE_FUNCTION_GRAPH_TRACER 56 select HAVE_FUNCTION_GRAPH_FP_TEST 57 select HAVE_SYSCALL_TRACEPOINTS 58 select SYSCTL_EXCEPTION_TRACE 59 select HAVE_KVM 60 select HAVE_ARCH_KGDB 61 select HAVE_ARCH_TRACEHOOK 62 select HAVE_GENERIC_DMA_COHERENT if X86_32 63 select HAVE_EFFICIENT_UNALIGNED_ACCESS 64 select USER_STACKTRACE_SUPPORT 65 select HAVE_REGS_AND_STACK_ACCESS_API 66 select HAVE_DMA_API_DEBUG 67 select HAVE_KERNEL_GZIP 68 select HAVE_KERNEL_BZIP2 69 select HAVE_KERNEL_LZMA 70 select HAVE_KERNEL_XZ 71 select HAVE_KERNEL_LZO 72 select HAVE_KERNEL_LZ4 73 select HAVE_HW_BREAKPOINT 74 select HAVE_MIXED_BREAKPOINTS_REGS 75 select PERF_EVENTS 76 select HAVE_PERF_EVENTS_NMI 77 select HAVE_PERF_REGS 78 select HAVE_PERF_USER_STACK_DUMP 79 select HAVE_DEBUG_KMEMLEAK 80 select ANON_INODES 81 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 82 select HAVE_CMPXCHG_LOCAL 83 select HAVE_CMPXCHG_DOUBLE 84 select HAVE_ARCH_KMEMCHECK 85 select HAVE_USER_RETURN_NOTIFIER 86 select ARCH_BINFMT_ELF_RANDOMIZE_PIE 87 select HAVE_ARCH_JUMP_LABEL 88 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE 89 select SPARSE_IRQ 90 select GENERIC_FIND_FIRST_BIT 91 select GENERIC_IRQ_PROBE 92 select GENERIC_PENDING_IRQ if SMP 93 select GENERIC_IRQ_SHOW 94 select GENERIC_CLOCKEVENTS_MIN_ADJUST 95 select IRQ_FORCED_THREADING 96 select HAVE_BPF_JIT if X86_64 97 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 98 select CLKEVT_I8253 99 select ARCH_HAVE_NMI_SAFE_CMPXCHG 100 select GENERIC_IOMAP 101 select DCACHE_WORD_ACCESS 102 select GENERIC_SMP_IDLE_THREAD 103 select ARCH_WANT_IPC_PARSE_VERSION if X86_32 104 select HAVE_ARCH_SECCOMP_FILTER 105 select BUILDTIME_EXTABLE_SORT 106 select GENERIC_CMOS_UPDATE 107 select HAVE_ARCH_SOFT_DIRTY if X86_64 108 select CLOCKSOURCE_WATCHDOG 109 select GENERIC_CLOCKEVENTS 110 select ARCH_CLOCKSOURCE_DATA 111 select CLOCKSOURCE_VALIDATE_LAST_CYCLE 112 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 113 select GENERIC_TIME_VSYSCALL 114 select GENERIC_STRNCPY_FROM_USER 115 select GENERIC_STRNLEN_USER 116 select HAVE_CONTEXT_TRACKING if X86_64 117 select HAVE_IRQ_TIME_ACCOUNTING 118 select VIRT_TO_BUS 119 select MODULES_USE_ELF_REL if X86_32 120 select MODULES_USE_ELF_RELA if X86_64 121 select CLONE_BACKWARDS if X86_32 122 select ARCH_USE_BUILTIN_BSWAP 123 select ARCH_USE_QUEUE_RWLOCK 124 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION 125 select OLD_SIGACTION if X86_32 126 select COMPAT_OLD_SIGACTION if IA32_EMULATION 127 select RTC_LIB 128 select HAVE_DEBUG_STACKOVERFLOW 129 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 130 select HAVE_CC_STACKPROTECTOR 131 select GENERIC_CPU_AUTOPROBE 132 select HAVE_ARCH_AUDITSYSCALL 133 select ARCH_SUPPORTS_ATOMIC_RMW 134 select HAVE_ACPI_APEI if ACPI 135 select HAVE_ACPI_APEI_NMI if ACPI 136 137config INSTRUCTION_DECODER 138 def_bool y 139 depends on KPROBES || PERF_EVENTS || UPROBES 140 141config OUTPUT_FORMAT 142 string 143 default "elf32-i386" if X86_32 144 default "elf64-x86-64" if X86_64 145 146config ARCH_DEFCONFIG 147 string 148 default "arch/x86/configs/i386_defconfig" if X86_32 149 default "arch/x86/configs/x86_64_defconfig" if X86_64 150 151config LOCKDEP_SUPPORT 152 def_bool y 153 154config STACKTRACE_SUPPORT 155 def_bool y 156 157config HAVE_LATENCYTOP_SUPPORT 158 def_bool y 159 160config MMU 161 def_bool y 162 163config SBUS 164 bool 165 166config NEED_DMA_MAP_STATE 167 def_bool y 168 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG 169 170config NEED_SG_DMA_LENGTH 171 def_bool y 172 173config GENERIC_ISA_DMA 174 def_bool y 175 depends on ISA_DMA_API 176 177config GENERIC_BUG 178 def_bool y 179 depends on BUG 180 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 181 182config GENERIC_BUG_RELATIVE_POINTERS 183 bool 184 185config GENERIC_HWEIGHT 186 def_bool y 187 188config ARCH_MAY_HAVE_PC_FDC 189 def_bool y 190 depends on ISA_DMA_API 191 192config RWSEM_XCHGADD_ALGORITHM 193 def_bool y 194 195config GENERIC_CALIBRATE_DELAY 196 def_bool y 197 198config ARCH_HAS_CPU_RELAX 199 def_bool y 200 201config ARCH_HAS_CACHE_LINE_SIZE 202 def_bool y 203 204config HAVE_SETUP_PER_CPU_AREA 205 def_bool y 206 207config NEED_PER_CPU_EMBED_FIRST_CHUNK 208 def_bool y 209 210config NEED_PER_CPU_PAGE_FIRST_CHUNK 211 def_bool y 212 213config ARCH_HIBERNATION_POSSIBLE 214 def_bool y 215 216config ARCH_SUSPEND_POSSIBLE 217 def_bool y 218 219config ARCH_WANT_HUGE_PMD_SHARE 220 def_bool y 221 222config ARCH_WANT_GENERAL_HUGETLB 223 def_bool y 224 225config ZONE_DMA32 226 bool 227 default X86_64 228 229config AUDIT_ARCH 230 bool 231 default X86_64 232 233config ARCH_SUPPORTS_OPTIMIZED_INLINING 234 def_bool y 235 236config ARCH_SUPPORTS_DEBUG_PAGEALLOC 237 def_bool y 238 239config HAVE_INTEL_TXT 240 def_bool y 241 depends on INTEL_IOMMU && ACPI 242 243config X86_32_SMP 244 def_bool y 245 depends on X86_32 && SMP 246 247config X86_64_SMP 248 def_bool y 249 depends on X86_64 && SMP 250 251config X86_HT 252 def_bool y 253 depends on SMP 254 255config X86_32_LAZY_GS 256 def_bool y 257 depends on X86_32 && !CC_STACKPROTECTOR 258 259config ARCH_HWEIGHT_CFLAGS 260 string 261 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32 262 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_64 263 264config ARCH_SUPPORTS_UPROBES 265 def_bool y 266 267config FIX_EARLYCON_MEM 268 def_bool y 269 270source "init/Kconfig" 271source "kernel/Kconfig.freezer" 272 273menu "Processor type and features" 274 275config ZONE_DMA 276 bool "DMA memory allocation support" if EXPERT 277 default y 278 help 279 DMA memory allocation support allows devices with less than 32-bit 280 addressing to allocate within the first 16MB of address space. 281 Disable if no such devices will be used. 282 283 If unsure, say Y. 284 285config SMP 286 bool "Symmetric multi-processing support" 287 ---help--- 288 This enables support for systems with more than one CPU. If you have 289 a system with only one CPU, say N. If you have a system with more 290 than one CPU, say Y. 291 292 If you say N here, the kernel will run on uni- and multiprocessor 293 machines, but will use only one CPU of a multiprocessor machine. If 294 you say Y here, the kernel will run on many, but not all, 295 uniprocessor machines. On a uniprocessor machine, the kernel 296 will run faster if you say N here. 297 298 Note that if you say Y here and choose architecture "586" or 299 "Pentium" under "Processor family", the kernel will not work on 486 300 architectures. Similarly, multiprocessor kernels for the "PPro" 301 architecture may not work on all Pentium based boards. 302 303 People using multiprocessor machines who say Y here should also say 304 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 305 Management" code will be disabled if you say Y here. 306 307 See also <file:Documentation/x86/i386/IO-APIC.txt>, 308 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 309 <http://www.tldp.org/docs.html#howto>. 310 311 If you don't know what to do here, say N. 312 313config X86_X2APIC 314 bool "Support x2apic" 315 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP 316 ---help--- 317 This enables x2apic support on CPUs that have this feature. 318 319 This allows 32-bit apic IDs (so it can support very large systems), 320 and accesses the local apic via MSRs not via mmio. 321 322 If you don't know what to do here, say N. 323 324config X86_MPPARSE 325 bool "Enable MPS table" if ACPI || SFI 326 default y 327 depends on X86_LOCAL_APIC 328 ---help--- 329 For old smp systems that do not have proper acpi support. Newer systems 330 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 331 332config X86_BIGSMP 333 bool "Support for big SMP systems with more than 8 CPUs" 334 depends on X86_32 && SMP 335 ---help--- 336 This option is needed for the systems that have more than 8 CPUs 337 338config GOLDFISH 339 def_bool y 340 depends on X86_GOLDFISH 341 342if X86_32 343config X86_EXTENDED_PLATFORM 344 bool "Support for extended (non-PC) x86 platforms" 345 default y 346 ---help--- 347 If you disable this option then the kernel will only support 348 standard PC platforms. (which covers the vast majority of 349 systems out there.) 350 351 If you enable this option then you'll be able to select support 352 for the following (non-PC) 32 bit x86 platforms: 353 Goldfish (Android emulator) 354 AMD Elan 355 RDC R-321x SoC 356 SGI 320/540 (Visual Workstation) 357 STA2X11-based (e.g. Northville) 358 Moorestown MID devices 359 360 If you have one of these systems, or if you want to build a 361 generic distribution kernel, say Y here - otherwise say N. 362endif 363 364if X86_64 365config X86_EXTENDED_PLATFORM 366 bool "Support for extended (non-PC) x86 platforms" 367 default y 368 ---help--- 369 If you disable this option then the kernel will only support 370 standard PC platforms. (which covers the vast majority of 371 systems out there.) 372 373 If you enable this option then you'll be able to select support 374 for the following (non-PC) 64 bit x86 platforms: 375 Numascale NumaChip 376 ScaleMP vSMP 377 SGI Ultraviolet 378 379 If you have one of these systems, or if you want to build a 380 generic distribution kernel, say Y here - otherwise say N. 381endif 382# This is an alphabetically sorted list of 64 bit extended platforms 383# Please maintain the alphabetic order if and when there are additions 384config X86_NUMACHIP 385 bool "Numascale NumaChip" 386 depends on X86_64 387 depends on X86_EXTENDED_PLATFORM 388 depends on NUMA 389 depends on SMP 390 depends on X86_X2APIC 391 depends on PCI_MMCONFIG 392 ---help--- 393 Adds support for Numascale NumaChip large-SMP systems. Needed to 394 enable more than ~168 cores. 395 If you don't have one of these, you should say N here. 396 397config X86_VSMP 398 bool "ScaleMP vSMP" 399 select HYPERVISOR_GUEST 400 select PARAVIRT 401 depends on X86_64 && PCI 402 depends on X86_EXTENDED_PLATFORM 403 depends on SMP 404 ---help--- 405 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 406 supposed to run on these EM64T-based machines. Only choose this option 407 if you have one of these machines. 408 409config X86_UV 410 bool "SGI Ultraviolet" 411 depends on X86_64 412 depends on X86_EXTENDED_PLATFORM 413 depends on NUMA 414 depends on X86_X2APIC 415 ---help--- 416 This option is needed in order to support SGI Ultraviolet systems. 417 If you don't have one of these, you should say N here. 418 419# Following is an alphabetically sorted list of 32 bit extended platforms 420# Please maintain the alphabetic order if and when there are additions 421 422config X86_GOLDFISH 423 bool "Goldfish (Virtual Platform)" 424 depends on X86_EXTENDED_PLATFORM 425 ---help--- 426 Enable support for the Goldfish virtual platform used primarily 427 for Android development. Unless you are building for the Android 428 Goldfish emulator say N here. 429 430config X86_INTEL_CE 431 bool "CE4100 TV platform" 432 depends on PCI 433 depends on PCI_GODIRECT 434 depends on X86_32 435 depends on X86_EXTENDED_PLATFORM 436 select X86_REBOOTFIXUPS 437 select OF 438 select OF_EARLY_FLATTREE 439 select IRQ_DOMAIN 440 ---help--- 441 Select for the Intel CE media processor (CE4100) SOC. 442 This option compiles in support for the CE4100 SOC for settop 443 boxes and media devices. 444 445config X86_INTEL_MID 446 bool "Intel MID platform support" 447 depends on X86_32 448 depends on X86_EXTENDED_PLATFORM 449 depends on X86_PLATFORM_DEVICES 450 depends on PCI 451 depends on PCI_GOANY 452 depends on X86_IO_APIC 453 select SFI 454 select I2C 455 select DW_APB_TIMER 456 select APB_TIMER 457 select INTEL_SCU_IPC 458 select MFD_INTEL_MSIC 459 ---help--- 460 Select to build a kernel capable of supporting Intel MID (Mobile 461 Internet Device) platform systems which do not have the PCI legacy 462 interfaces. If you are building for a PC class system say N here. 463 464 Intel MID platforms are based on an Intel processor and chipset which 465 consume less power than most of the x86 derivatives. 466 467config X86_INTEL_LPSS 468 bool "Intel Low Power Subsystem Support" 469 depends on ACPI 470 select COMMON_CLK 471 select PINCTRL 472 ---help--- 473 Select to build support for Intel Low Power Subsystem such as 474 found on Intel Lynxpoint PCH. Selecting this option enables 475 things like clock tree (common clock framework) and pincontrol 476 which are needed by the LPSS peripheral drivers. 477 478config X86_RDC321X 479 bool "RDC R-321x SoC" 480 depends on X86_32 481 depends on X86_EXTENDED_PLATFORM 482 select M486 483 select X86_REBOOTFIXUPS 484 ---help--- 485 This option is needed for RDC R-321x system-on-chip, also known 486 as R-8610-(G). 487 If you don't have one of these chips, you should say N here. 488 489config X86_32_NON_STANDARD 490 bool "Support non-standard 32-bit SMP architectures" 491 depends on X86_32 && SMP 492 depends on X86_EXTENDED_PLATFORM 493 ---help--- 494 This option compiles in the bigsmp and STA2X11 default 495 subarchitectures. It is intended for a generic binary 496 kernel. If you select them all, kernel will probe it one by 497 one and will fallback to default. 498 499# Alphabetically sorted list of Non standard 32 bit platforms 500 501config X86_SUPPORTS_MEMORY_FAILURE 502 def_bool y 503 # MCE code calls memory_failure(): 504 depends on X86_MCE 505 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 506 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 507 depends on X86_64 || !SPARSEMEM 508 select ARCH_SUPPORTS_MEMORY_FAILURE 509 510config STA2X11 511 bool "STA2X11 Companion Chip Support" 512 depends on X86_32_NON_STANDARD && PCI 513 select X86_DEV_DMA_OPS 514 select X86_DMA_REMAP 515 select SWIOTLB 516 select MFD_STA2X11 517 select ARCH_REQUIRE_GPIOLIB 518 default n 519 ---help--- 520 This adds support for boards based on the STA2X11 IO-Hub, 521 a.k.a. "ConneXt". The chip is used in place of the standard 522 PC chipset, so all "standard" peripherals are missing. If this 523 option is selected the kernel will still be able to boot on 524 standard PC machines. 525 526config X86_32_IRIS 527 tristate "Eurobraille/Iris poweroff module" 528 depends on X86_32 529 ---help--- 530 The Iris machines from EuroBraille do not have APM or ACPI support 531 to shut themselves down properly. A special I/O sequence is 532 needed to do so, which is what this module does at 533 kernel shutdown. 534 535 This is only for Iris machines from EuroBraille. 536 537 If unused, say N. 538 539config SCHED_OMIT_FRAME_POINTER 540 def_bool y 541 prompt "Single-depth WCHAN output" 542 depends on X86 543 ---help--- 544 Calculate simpler /proc/<PID>/wchan values. If this option 545 is disabled then wchan values will recurse back to the 546 caller function. This provides more accurate wchan values, 547 at the expense of slightly more scheduling overhead. 548 549 If in doubt, say "Y". 550 551menuconfig HYPERVISOR_GUEST 552 bool "Linux guest support" 553 ---help--- 554 Say Y here to enable options for running Linux under various hyper- 555 visors. This option enables basic hypervisor detection and platform 556 setup. 557 558 If you say N, all options in this submenu will be skipped and 559 disabled, and Linux guest support won't be built in. 560 561if HYPERVISOR_GUEST 562 563config PARAVIRT 564 bool "Enable paravirtualization code" 565 ---help--- 566 This changes the kernel so it can modify itself when it is run 567 under a hypervisor, potentially improving performance significantly 568 over full virtualization. However, when run without a hypervisor 569 the kernel is theoretically slower and slightly larger. 570 571config PARAVIRT_DEBUG 572 bool "paravirt-ops debugging" 573 depends on PARAVIRT && DEBUG_KERNEL 574 ---help--- 575 Enable to debug paravirt_ops internals. Specifically, BUG if 576 a paravirt_op is missing when it is called. 577 578config PARAVIRT_SPINLOCKS 579 bool "Paravirtualization layer for spinlocks" 580 depends on PARAVIRT && SMP 581 select UNINLINE_SPIN_UNLOCK 582 ---help--- 583 Paravirtualized spinlocks allow a pvops backend to replace the 584 spinlock implementation with something virtualization-friendly 585 (for example, block the virtual CPU rather than spinning). 586 587 It has a minimal impact on native kernels and gives a nice performance 588 benefit on paravirtualized KVM / Xen kernels. 589 590 If you are unsure how to answer this question, answer Y. 591 592source "arch/x86/xen/Kconfig" 593 594config KVM_GUEST 595 bool "KVM Guest support (including kvmclock)" 596 depends on PARAVIRT 597 select PARAVIRT_CLOCK 598 default y 599 ---help--- 600 This option enables various optimizations for running under the KVM 601 hypervisor. It includes a paravirtualized clock, so that instead 602 of relying on a PIT (or probably other) emulation by the 603 underlying device model, the host provides the guest with 604 timing infrastructure such as time of day, and system time 605 606config KVM_DEBUG_FS 607 bool "Enable debug information for KVM Guests in debugfs" 608 depends on KVM_GUEST && DEBUG_FS 609 default n 610 ---help--- 611 This option enables collection of various statistics for KVM guest. 612 Statistics are displayed in debugfs filesystem. Enabling this option 613 may incur significant overhead. 614 615source "arch/x86/lguest/Kconfig" 616 617config PARAVIRT_TIME_ACCOUNTING 618 bool "Paravirtual steal time accounting" 619 depends on PARAVIRT 620 default n 621 ---help--- 622 Select this option to enable fine granularity task steal time 623 accounting. Time spent executing other tasks in parallel with 624 the current vCPU is discounted from the vCPU power. To account for 625 that, there can be a small performance impact. 626 627 If in doubt, say N here. 628 629config PARAVIRT_CLOCK 630 bool 631 632endif #HYPERVISOR_GUEST 633 634config NO_BOOTMEM 635 def_bool y 636 637config MEMTEST 638 bool "Memtest" 639 ---help--- 640 This option adds a kernel parameter 'memtest', which allows memtest 641 to be set. 642 memtest=0, mean disabled; -- default 643 memtest=1, mean do 1 test pattern; 644 ... 645 memtest=4, mean do 4 test patterns. 646 If you are unsure how to answer this question, answer N. 647 648source "arch/x86/Kconfig.cpu" 649 650config HPET_TIMER 651 def_bool X86_64 652 prompt "HPET Timer Support" if X86_32 653 ---help--- 654 Use the IA-PC HPET (High Precision Event Timer) to manage 655 time in preference to the PIT and RTC, if a HPET is 656 present. 657 HPET is the next generation timer replacing legacy 8254s. 658 The HPET provides a stable time base on SMP 659 systems, unlike the TSC, but it is more expensive to access, 660 as it is off-chip. You can find the HPET spec at 661 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>. 662 663 You can safely choose Y here. However, HPET will only be 664 activated if the platform and the BIOS support this feature. 665 Otherwise the 8254 will be used for timing services. 666 667 Choose N to continue using the legacy 8254 timer. 668 669config HPET_EMULATE_RTC 670 def_bool y 671 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 672 673config APB_TIMER 674 def_bool y if X86_INTEL_MID 675 prompt "Intel MID APB Timer Support" if X86_INTEL_MID 676 select DW_APB_TIMER 677 depends on X86_INTEL_MID && SFI 678 help 679 APB timer is the replacement for 8254, HPET on X86 MID platforms. 680 The APBT provides a stable time base on SMP 681 systems, unlike the TSC, but it is more expensive to access, 682 as it is off-chip. APB timers are always running regardless of CPU 683 C states, they are used as per CPU clockevent device when possible. 684 685# Mark as expert because too many people got it wrong. 686# The code disables itself when not needed. 687config DMI 688 default y 689 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 690 bool "Enable DMI scanning" if EXPERT 691 ---help--- 692 Enabled scanning of DMI to identify machine quirks. Say Y 693 here unless you have verified that your setup is not 694 affected by entries in the DMI blacklist. Required by PNP 695 BIOS code. 696 697config GART_IOMMU 698 bool "Old AMD GART IOMMU support" 699 select SWIOTLB 700 depends on X86_64 && PCI && AMD_NB 701 ---help--- 702 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 703 GART based hardware IOMMUs. 704 705 The GART supports full DMA access for devices with 32-bit access 706 limitations, on systems with more than 3 GB. This is usually needed 707 for USB, sound, many IDE/SATA chipsets and some other devices. 708 709 Newer systems typically have a modern AMD IOMMU, supported via 710 the CONFIG_AMD_IOMMU=y config option. 711 712 In normal configurations this driver is only active when needed: 713 there's more than 3 GB of memory and the system contains a 714 32-bit limited device. 715 716 If unsure, say Y. 717 718config CALGARY_IOMMU 719 bool "IBM Calgary IOMMU support" 720 select SWIOTLB 721 depends on X86_64 && PCI 722 ---help--- 723 Support for hardware IOMMUs in IBM's xSeries x366 and x460 724 systems. Needed to run systems with more than 3GB of memory 725 properly with 32-bit PCI devices that do not support DAC 726 (Double Address Cycle). Calgary also supports bus level 727 isolation, where all DMAs pass through the IOMMU. This 728 prevents them from going anywhere except their intended 729 destination. This catches hard-to-find kernel bugs and 730 mis-behaving drivers and devices that do not use the DMA-API 731 properly to set up their DMA buffers. The IOMMU can be 732 turned off at boot time with the iommu=off parameter. 733 Normally the kernel will make the right choice by itself. 734 If unsure, say Y. 735 736config CALGARY_IOMMU_ENABLED_BY_DEFAULT 737 def_bool y 738 prompt "Should Calgary be enabled by default?" 739 depends on CALGARY_IOMMU 740 ---help--- 741 Should Calgary be enabled by default? if you choose 'y', Calgary 742 will be used (if it exists). If you choose 'n', Calgary will not be 743 used even if it exists. If you choose 'n' and would like to use 744 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 745 If unsure, say Y. 746 747# need this always selected by IOMMU for the VIA workaround 748config SWIOTLB 749 def_bool y if X86_64 750 ---help--- 751 Support for software bounce buffers used on x86-64 systems 752 which don't have a hardware IOMMU. Using this PCI devices 753 which can only access 32-bits of memory can be used on systems 754 with more than 3 GB of memory. 755 If unsure, say Y. 756 757config IOMMU_HELPER 758 def_bool y 759 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 760 761config MAXSMP 762 bool "Enable Maximum number of SMP Processors and NUMA Nodes" 763 depends on X86_64 && SMP && DEBUG_KERNEL 764 select CPUMASK_OFFSTACK 765 ---help--- 766 Enable maximum number of CPUS and NUMA Nodes for this architecture. 767 If unsure, say N. 768 769config NR_CPUS 770 int "Maximum number of CPUs" if SMP && !MAXSMP 771 range 2 8 if SMP && X86_32 && !X86_BIGSMP 772 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK 773 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64 774 default "1" if !SMP 775 default "8192" if MAXSMP 776 default "32" if SMP && X86_BIGSMP 777 default "8" if SMP 778 ---help--- 779 This allows you to specify the maximum number of CPUs which this 780 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 781 supported value is 4096, otherwise the maximum value is 512. The 782 minimum value which makes sense is 2. 783 784 This is purely to save memory - each supported CPU adds 785 approximately eight kilobytes to the kernel image. 786 787config SCHED_SMT 788 bool "SMT (Hyperthreading) scheduler support" 789 depends on X86_HT 790 ---help--- 791 SMT scheduler support improves the CPU scheduler's decision making 792 when dealing with Intel Pentium 4 chips with HyperThreading at a 793 cost of slightly increased overhead in some places. If unsure say 794 N here. 795 796config SCHED_MC 797 def_bool y 798 prompt "Multi-core scheduler support" 799 depends on X86_HT 800 ---help--- 801 Multi-core scheduler support improves the CPU scheduler's decision 802 making when dealing with multi-core CPU chips at a cost of slightly 803 increased overhead in some places. If unsure say N here. 804 805source "kernel/Kconfig.preempt" 806 807config X86_UP_APIC 808 bool "Local APIC support on uniprocessors" 809 depends on X86_32 && !SMP && !X86_32_NON_STANDARD && !PCI_MSI 810 ---help--- 811 A local APIC (Advanced Programmable Interrupt Controller) is an 812 integrated interrupt controller in the CPU. If you have a single-CPU 813 system which has a processor with a local APIC, you can say Y here to 814 enable and use it. If you say Y here even though your machine doesn't 815 have a local APIC, then the kernel will still run with no slowdown at 816 all. The local APIC supports CPU-generated self-interrupts (timer, 817 performance counters), and the NMI watchdog which detects hard 818 lockups. 819 820config X86_UP_IOAPIC 821 bool "IO-APIC support on uniprocessors" 822 depends on X86_UP_APIC 823 ---help--- 824 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 825 SMP-capable replacement for PC-style interrupt controllers. Most 826 SMP systems and many recent uniprocessor systems have one. 827 828 If you have a single-CPU system with an IO-APIC, you can say Y here 829 to use it. If you say Y here even though your machine doesn't have 830 an IO-APIC, then the kernel will still run with no slowdown at all. 831 832config X86_LOCAL_APIC 833 def_bool y 834 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 835 836config X86_IO_APIC 837 def_bool y 838 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC || PCI_MSI 839 select GENERIC_IRQ_LEGACY_ALLOC_HWIRQ 840 841config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 842 bool "Reroute for broken boot IRQs" 843 depends on X86_IO_APIC 844 ---help--- 845 This option enables a workaround that fixes a source of 846 spurious interrupts. This is recommended when threaded 847 interrupt handling is used on systems where the generation of 848 superfluous "boot interrupts" cannot be disabled. 849 850 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 851 entry in the chipset's IO-APIC is masked (as, e.g. the RT 852 kernel does during interrupt handling). On chipsets where this 853 boot IRQ generation cannot be disabled, this workaround keeps 854 the original IRQ line masked so that only the equivalent "boot 855 IRQ" is delivered to the CPUs. The workaround also tells the 856 kernel to set up the IRQ handler on the boot IRQ line. In this 857 way only one interrupt is delivered to the kernel. Otherwise 858 the spurious second interrupt may cause the kernel to bring 859 down (vital) interrupt lines. 860 861 Only affects "broken" chipsets. Interrupt sharing may be 862 increased on these systems. 863 864config X86_MCE 865 bool "Machine Check / overheating reporting" 866 default y 867 ---help--- 868 Machine Check support allows the processor to notify the 869 kernel if it detects a problem (e.g. overheating, data corruption). 870 The action the kernel takes depends on the severity of the problem, 871 ranging from warning messages to halting the machine. 872 873config X86_MCE_INTEL 874 def_bool y 875 prompt "Intel MCE features" 876 depends on X86_MCE && X86_LOCAL_APIC 877 ---help--- 878 Additional support for intel specific MCE features such as 879 the thermal monitor. 880 881config X86_MCE_AMD 882 def_bool y 883 prompt "AMD MCE features" 884 depends on X86_MCE && X86_LOCAL_APIC 885 ---help--- 886 Additional support for AMD specific MCE features such as 887 the DRAM Error Threshold. 888 889config X86_ANCIENT_MCE 890 bool "Support for old Pentium 5 / WinChip machine checks" 891 depends on X86_32 && X86_MCE 892 ---help--- 893 Include support for machine check handling on old Pentium 5 or WinChip 894 systems. These typically need to be enabled explicitly on the command 895 line. 896 897config X86_MCE_THRESHOLD 898 depends on X86_MCE_AMD || X86_MCE_INTEL 899 def_bool y 900 901config X86_MCE_INJECT 902 depends on X86_MCE 903 tristate "Machine check injector support" 904 ---help--- 905 Provide support for injecting machine checks for testing purposes. 906 If you don't know what a machine check is and you don't do kernel 907 QA it is safe to say n. 908 909config X86_THERMAL_VECTOR 910 def_bool y 911 depends on X86_MCE_INTEL 912 913config VM86 914 bool "Enable VM86 support" if EXPERT 915 default y 916 depends on X86_32 917 ---help--- 918 This option is required by programs like DOSEMU to run 919 16-bit real mode legacy code on x86 processors. It also may 920 be needed by software like XFree86 to initialize some video 921 cards via BIOS. Disabling this option saves about 6K. 922 923config X86_16BIT 924 bool "Enable support for 16-bit segments" if EXPERT 925 default y 926 ---help--- 927 This option is required by programs like Wine to run 16-bit 928 protected mode legacy code on x86 processors. Disabling 929 this option saves about 300 bytes on i386, or around 6K text 930 plus 16K runtime memory on x86-64, 931 932config X86_ESPFIX32 933 def_bool y 934 depends on X86_16BIT && X86_32 935 936config X86_ESPFIX64 937 def_bool y 938 depends on X86_16BIT && X86_64 939 940config TOSHIBA 941 tristate "Toshiba Laptop support" 942 depends on X86_32 943 ---help--- 944 This adds a driver to safely access the System Management Mode of 945 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 946 not work on models with a Phoenix BIOS. The System Management Mode 947 is used to set the BIOS and power saving options on Toshiba portables. 948 949 For information on utilities to make use of this driver see the 950 Toshiba Linux utilities web site at: 951 <http://www.buzzard.org.uk/toshiba/>. 952 953 Say Y if you intend to run this kernel on a Toshiba portable. 954 Say N otherwise. 955 956config I8K 957 tristate "Dell laptop support" 958 select HWMON 959 ---help--- 960 This adds a driver to safely access the System Management Mode 961 of the CPU on the Dell Inspiron 8000. The System Management Mode 962 is used to read cpu temperature and cooling fan status and to 963 control the fans on the I8K portables. 964 965 This driver has been tested only on the Inspiron 8000 but it may 966 also work with other Dell laptops. You can force loading on other 967 models by passing the parameter `force=1' to the module. Use at 968 your own risk. 969 970 For information on utilities to make use of this driver see the 971 I8K Linux utilities web site at: 972 <http://people.debian.org/~dz/i8k/> 973 974 Say Y if you intend to run this kernel on a Dell Inspiron 8000. 975 Say N otherwise. 976 977config X86_REBOOTFIXUPS 978 bool "Enable X86 board specific fixups for reboot" 979 depends on X86_32 980 ---help--- 981 This enables chipset and/or board specific fixups to be done 982 in order to get reboot to work correctly. This is only needed on 983 some combinations of hardware and BIOS. The symptom, for which 984 this config is intended, is when reboot ends with a stalled/hung 985 system. 986 987 Currently, the only fixup is for the Geode machines using 988 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 989 990 Say Y if you want to enable the fixup. Currently, it's safe to 991 enable this option even if you don't need it. 992 Say N otherwise. 993 994config MICROCODE 995 tristate "CPU microcode loading support" 996 depends on CPU_SUP_AMD || CPU_SUP_INTEL 997 select FW_LOADER 998 ---help--- 999 1000 If you say Y here, you will be able to update the microcode on 1001 certain Intel and AMD processors. The Intel support is for the 1002 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, 1003 Xeon etc. The AMD support is for families 0x10 and later. You will 1004 obviously need the actual microcode binary data itself which is not 1005 shipped with the Linux kernel. 1006 1007 This option selects the general module only, you need to select 1008 at least one vendor specific module as well. 1009 1010 To compile this driver as a module, choose M here: the module 1011 will be called microcode. 1012 1013config MICROCODE_INTEL 1014 bool "Intel microcode loading support" 1015 depends on MICROCODE 1016 default MICROCODE 1017 select FW_LOADER 1018 ---help--- 1019 This options enables microcode patch loading support for Intel 1020 processors. 1021 1022 For the current Intel microcode data package go to 1023 <https://downloadcenter.intel.com> and search for 1024 'Linux Processor Microcode Data File'. 1025 1026config MICROCODE_AMD 1027 bool "AMD microcode loading support" 1028 depends on MICROCODE 1029 select FW_LOADER 1030 ---help--- 1031 If you select this option, microcode patch loading support for AMD 1032 processors will be enabled. 1033 1034config MICROCODE_OLD_INTERFACE 1035 def_bool y 1036 depends on MICROCODE 1037 1038config MICROCODE_INTEL_EARLY 1039 def_bool n 1040 1041config MICROCODE_AMD_EARLY 1042 def_bool n 1043 1044config MICROCODE_EARLY 1045 bool "Early load microcode" 1046 depends on MICROCODE=y && BLK_DEV_INITRD 1047 select MICROCODE_INTEL_EARLY if MICROCODE_INTEL 1048 select MICROCODE_AMD_EARLY if MICROCODE_AMD 1049 default y 1050 help 1051 This option provides functionality to read additional microcode data 1052 at the beginning of initrd image. The data tells kernel to load 1053 microcode to CPU's as early as possible. No functional change if no 1054 microcode data is glued to the initrd, therefore it's safe to say Y. 1055 1056config X86_MSR 1057 tristate "/dev/cpu/*/msr - Model-specific register support" 1058 ---help--- 1059 This device gives privileged processes access to the x86 1060 Model-Specific Registers (MSRs). It is a character device with 1061 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1062 MSR accesses are directed to a specific CPU on multi-processor 1063 systems. 1064 1065config X86_CPUID 1066 tristate "/dev/cpu/*/cpuid - CPU information support" 1067 ---help--- 1068 This device gives processes access to the x86 CPUID instruction to 1069 be executed on a specific processor. It is a character device 1070 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1071 /dev/cpu/31/cpuid. 1072 1073choice 1074 prompt "High Memory Support" 1075 default HIGHMEM4G 1076 depends on X86_32 1077 1078config NOHIGHMEM 1079 bool "off" 1080 ---help--- 1081 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1082 However, the address space of 32-bit x86 processors is only 4 1083 Gigabytes large. That means that, if you have a large amount of 1084 physical memory, not all of it can be "permanently mapped" by the 1085 kernel. The physical memory that's not permanently mapped is called 1086 "high memory". 1087 1088 If you are compiling a kernel which will never run on a machine with 1089 more than 1 Gigabyte total physical RAM, answer "off" here (default 1090 choice and suitable for most users). This will result in a "3GB/1GB" 1091 split: 3GB are mapped so that each process sees a 3GB virtual memory 1092 space and the remaining part of the 4GB virtual memory space is used 1093 by the kernel to permanently map as much physical memory as 1094 possible. 1095 1096 If the machine has between 1 and 4 Gigabytes physical RAM, then 1097 answer "4GB" here. 1098 1099 If more than 4 Gigabytes is used then answer "64GB" here. This 1100 selection turns Intel PAE (Physical Address Extension) mode on. 1101 PAE implements 3-level paging on IA32 processors. PAE is fully 1102 supported by Linux, PAE mode is implemented on all recent Intel 1103 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1104 then the kernel will not boot on CPUs that don't support PAE! 1105 1106 The actual amount of total physical memory will either be 1107 auto detected or can be forced by using a kernel command line option 1108 such as "mem=256M". (Try "man bootparam" or see the documentation of 1109 your boot loader (lilo or loadlin) about how to pass options to the 1110 kernel at boot time.) 1111 1112 If unsure, say "off". 1113 1114config HIGHMEM4G 1115 bool "4GB" 1116 ---help--- 1117 Select this if you have a 32-bit processor and between 1 and 4 1118 gigabytes of physical RAM. 1119 1120config HIGHMEM64G 1121 bool "64GB" 1122 depends on !M486 1123 select X86_PAE 1124 ---help--- 1125 Select this if you have a 32-bit processor and more than 4 1126 gigabytes of physical RAM. 1127 1128endchoice 1129 1130choice 1131 prompt "Memory split" if EXPERT 1132 default VMSPLIT_3G 1133 depends on X86_32 1134 ---help--- 1135 Select the desired split between kernel and user memory. 1136 1137 If the address range available to the kernel is less than the 1138 physical memory installed, the remaining memory will be available 1139 as "high memory". Accessing high memory is a little more costly 1140 than low memory, as it needs to be mapped into the kernel first. 1141 Note that increasing the kernel address space limits the range 1142 available to user programs, making the address space there 1143 tighter. Selecting anything other than the default 3G/1G split 1144 will also likely make your kernel incompatible with binary-only 1145 kernel modules. 1146 1147 If you are not absolutely sure what you are doing, leave this 1148 option alone! 1149 1150 config VMSPLIT_3G 1151 bool "3G/1G user/kernel split" 1152 config VMSPLIT_3G_OPT 1153 depends on !X86_PAE 1154 bool "3G/1G user/kernel split (for full 1G low memory)" 1155 config VMSPLIT_2G 1156 bool "2G/2G user/kernel split" 1157 config VMSPLIT_2G_OPT 1158 depends on !X86_PAE 1159 bool "2G/2G user/kernel split (for full 2G low memory)" 1160 config VMSPLIT_1G 1161 bool "1G/3G user/kernel split" 1162endchoice 1163 1164config PAGE_OFFSET 1165 hex 1166 default 0xB0000000 if VMSPLIT_3G_OPT 1167 default 0x80000000 if VMSPLIT_2G 1168 default 0x78000000 if VMSPLIT_2G_OPT 1169 default 0x40000000 if VMSPLIT_1G 1170 default 0xC0000000 1171 depends on X86_32 1172 1173config HIGHMEM 1174 def_bool y 1175 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1176 1177config X86_PAE 1178 bool "PAE (Physical Address Extension) Support" 1179 depends on X86_32 && !HIGHMEM4G 1180 ---help--- 1181 PAE is required for NX support, and furthermore enables 1182 larger swapspace support for non-overcommit purposes. It 1183 has the cost of more pagetable lookup overhead, and also 1184 consumes more pagetable space per process. 1185 1186config ARCH_PHYS_ADDR_T_64BIT 1187 def_bool y 1188 depends on X86_64 || X86_PAE 1189 1190config ARCH_DMA_ADDR_T_64BIT 1191 def_bool y 1192 depends on X86_64 || HIGHMEM64G 1193 1194config DIRECT_GBPAGES 1195 bool "Enable 1GB pages for kernel pagetables" if EXPERT 1196 default y 1197 depends on X86_64 1198 ---help--- 1199 Allow the kernel linear mapping to use 1GB pages on CPUs that 1200 support it. This can improve the kernel's performance a tiny bit by 1201 reducing TLB pressure. If in doubt, say "Y". 1202 1203# Common NUMA Features 1204config NUMA 1205 bool "Numa Memory Allocation and Scheduler Support" 1206 depends on SMP 1207 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1208 default y if X86_BIGSMP 1209 ---help--- 1210 Enable NUMA (Non Uniform Memory Access) support. 1211 1212 The kernel will try to allocate memory used by a CPU on the 1213 local memory controller of the CPU and add some more 1214 NUMA awareness to the kernel. 1215 1216 For 64-bit this is recommended if the system is Intel Core i7 1217 (or later), AMD Opteron, or EM64T NUMA. 1218 1219 For 32-bit this is only needed if you boot a 32-bit 1220 kernel on a 64-bit NUMA platform. 1221 1222 Otherwise, you should say N. 1223 1224config AMD_NUMA 1225 def_bool y 1226 prompt "Old style AMD Opteron NUMA detection" 1227 depends on X86_64 && NUMA && PCI 1228 ---help--- 1229 Enable AMD NUMA node topology detection. You should say Y here if 1230 you have a multi processor AMD system. This uses an old method to 1231 read the NUMA configuration directly from the builtin Northbridge 1232 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1233 which also takes priority if both are compiled in. 1234 1235config X86_64_ACPI_NUMA 1236 def_bool y 1237 prompt "ACPI NUMA detection" 1238 depends on X86_64 && NUMA && ACPI && PCI 1239 select ACPI_NUMA 1240 ---help--- 1241 Enable ACPI SRAT based node topology detection. 1242 1243# Some NUMA nodes have memory ranges that span 1244# other nodes. Even though a pfn is valid and 1245# between a node's start and end pfns, it may not 1246# reside on that node. See memmap_init_zone() 1247# for details. 1248config NODES_SPAN_OTHER_NODES 1249 def_bool y 1250 depends on X86_64_ACPI_NUMA 1251 1252config NUMA_EMU 1253 bool "NUMA emulation" 1254 depends on NUMA 1255 ---help--- 1256 Enable NUMA emulation. A flat machine will be split 1257 into virtual nodes when booted with "numa=fake=N", where N is the 1258 number of nodes. This is only useful for debugging. 1259 1260config NODES_SHIFT 1261 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1262 range 1 10 1263 default "10" if MAXSMP 1264 default "6" if X86_64 1265 default "3" 1266 depends on NEED_MULTIPLE_NODES 1267 ---help--- 1268 Specify the maximum number of NUMA Nodes available on the target 1269 system. Increases memory reserved to accommodate various tables. 1270 1271config ARCH_HAVE_MEMORY_PRESENT 1272 def_bool y 1273 depends on X86_32 && DISCONTIGMEM 1274 1275config NEED_NODE_MEMMAP_SIZE 1276 def_bool y 1277 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1278 1279config ARCH_FLATMEM_ENABLE 1280 def_bool y 1281 depends on X86_32 && !NUMA 1282 1283config ARCH_DISCONTIGMEM_ENABLE 1284 def_bool y 1285 depends on NUMA && X86_32 1286 1287config ARCH_DISCONTIGMEM_DEFAULT 1288 def_bool y 1289 depends on NUMA && X86_32 1290 1291config ARCH_SPARSEMEM_ENABLE 1292 def_bool y 1293 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1294 select SPARSEMEM_STATIC if X86_32 1295 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1296 1297config ARCH_SPARSEMEM_DEFAULT 1298 def_bool y 1299 depends on X86_64 1300 1301config ARCH_SELECT_MEMORY_MODEL 1302 def_bool y 1303 depends on ARCH_SPARSEMEM_ENABLE 1304 1305config ARCH_MEMORY_PROBE 1306 bool "Enable sysfs memory/probe interface" 1307 depends on X86_64 && MEMORY_HOTPLUG 1308 help 1309 This option enables a sysfs memory/probe interface for testing. 1310 See Documentation/memory-hotplug.txt for more information. 1311 If you are unsure how to answer this question, answer N. 1312 1313config ARCH_PROC_KCORE_TEXT 1314 def_bool y 1315 depends on X86_64 && PROC_KCORE 1316 1317config ILLEGAL_POINTER_VALUE 1318 hex 1319 default 0 if X86_32 1320 default 0xdead000000000000 if X86_64 1321 1322source "mm/Kconfig" 1323 1324config HIGHPTE 1325 bool "Allocate 3rd-level pagetables from highmem" 1326 depends on HIGHMEM 1327 ---help--- 1328 The VM uses one page table entry for each page of physical memory. 1329 For systems with a lot of RAM, this can be wasteful of precious 1330 low memory. Setting this option will put user-space page table 1331 entries in high memory. 1332 1333config X86_CHECK_BIOS_CORRUPTION 1334 bool "Check for low memory corruption" 1335 ---help--- 1336 Periodically check for memory corruption in low memory, which 1337 is suspected to be caused by BIOS. Even when enabled in the 1338 configuration, it is disabled at runtime. Enable it by 1339 setting "memory_corruption_check=1" on the kernel command 1340 line. By default it scans the low 64k of memory every 60 1341 seconds; see the memory_corruption_check_size and 1342 memory_corruption_check_period parameters in 1343 Documentation/kernel-parameters.txt to adjust this. 1344 1345 When enabled with the default parameters, this option has 1346 almost no overhead, as it reserves a relatively small amount 1347 of memory and scans it infrequently. It both detects corruption 1348 and prevents it from affecting the running system. 1349 1350 It is, however, intended as a diagnostic tool; if repeatable 1351 BIOS-originated corruption always affects the same memory, 1352 you can use memmap= to prevent the kernel from using that 1353 memory. 1354 1355config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1356 bool "Set the default setting of memory_corruption_check" 1357 depends on X86_CHECK_BIOS_CORRUPTION 1358 default y 1359 ---help--- 1360 Set whether the default state of memory_corruption_check is 1361 on or off. 1362 1363config X86_RESERVE_LOW 1364 int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1365 default 64 1366 range 4 640 1367 ---help--- 1368 Specify the amount of low memory to reserve for the BIOS. 1369 1370 The first page contains BIOS data structures that the kernel 1371 must not use, so that page must always be reserved. 1372 1373 By default we reserve the first 64K of physical RAM, as a 1374 number of BIOSes are known to corrupt that memory range 1375 during events such as suspend/resume or monitor cable 1376 insertion, so it must not be used by the kernel. 1377 1378 You can set this to 4 if you are absolutely sure that you 1379 trust the BIOS to get all its memory reservations and usages 1380 right. If you know your BIOS have problems beyond the 1381 default 64K area, you can set this to 640 to avoid using the 1382 entire low memory range. 1383 1384 If you have doubts about the BIOS (e.g. suspend/resume does 1385 not work or there's kernel crashes after certain hardware 1386 hotplug events) then you might want to enable 1387 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1388 typical corruption patterns. 1389 1390 Leave this to the default value of 64 if you are unsure. 1391 1392config MATH_EMULATION 1393 bool 1394 prompt "Math emulation" if X86_32 1395 ---help--- 1396 Linux can emulate a math coprocessor (used for floating point 1397 operations) if you don't have one. 486DX and Pentium processors have 1398 a math coprocessor built in, 486SX and 386 do not, unless you added 1399 a 487DX or 387, respectively. (The messages during boot time can 1400 give you some hints here ["man dmesg"].) Everyone needs either a 1401 coprocessor or this emulation. 1402 1403 If you don't have a math coprocessor, you need to say Y here; if you 1404 say Y here even though you have a coprocessor, the coprocessor will 1405 be used nevertheless. (This behavior can be changed with the kernel 1406 command line option "no387", which comes handy if your coprocessor 1407 is broken. Try "man bootparam" or see the documentation of your boot 1408 loader (lilo or loadlin) about how to pass options to the kernel at 1409 boot time.) This means that it is a good idea to say Y here if you 1410 intend to use this kernel on different machines. 1411 1412 More information about the internals of the Linux math coprocessor 1413 emulation can be found in <file:arch/x86/math-emu/README>. 1414 1415 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1416 kernel, it won't hurt. 1417 1418config MTRR 1419 def_bool y 1420 prompt "MTRR (Memory Type Range Register) support" if EXPERT 1421 ---help--- 1422 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1423 the Memory Type Range Registers (MTRRs) may be used to control 1424 processor access to memory ranges. This is most useful if you have 1425 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1426 allows bus write transfers to be combined into a larger transfer 1427 before bursting over the PCI/AGP bus. This can increase performance 1428 of image write operations 2.5 times or more. Saying Y here creates a 1429 /proc/mtrr file which may be used to manipulate your processor's 1430 MTRRs. Typically the X server should use this. 1431 1432 This code has a reasonably generic interface so that similar 1433 control registers on other processors can be easily supported 1434 as well: 1435 1436 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1437 Registers (ARRs) which provide a similar functionality to MTRRs. For 1438 these, the ARRs are used to emulate the MTRRs. 1439 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1440 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1441 write-combining. All of these processors are supported by this code 1442 and it makes sense to say Y here if you have one of them. 1443 1444 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1445 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1446 can lead to all sorts of problems, so it's good to say Y here. 1447 1448 You can safely say Y even if your machine doesn't have MTRRs, you'll 1449 just add about 9 KB to your kernel. 1450 1451 See <file:Documentation/x86/mtrr.txt> for more information. 1452 1453config MTRR_SANITIZER 1454 def_bool y 1455 prompt "MTRR cleanup support" 1456 depends on MTRR 1457 ---help--- 1458 Convert MTRR layout from continuous to discrete, so X drivers can 1459 add writeback entries. 1460 1461 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1462 The largest mtrr entry size for a continuous block can be set with 1463 mtrr_chunk_size. 1464 1465 If unsure, say Y. 1466 1467config MTRR_SANITIZER_ENABLE_DEFAULT 1468 int "MTRR cleanup enable value (0-1)" 1469 range 0 1 1470 default "0" 1471 depends on MTRR_SANITIZER 1472 ---help--- 1473 Enable mtrr cleanup default value 1474 1475config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1476 int "MTRR cleanup spare reg num (0-7)" 1477 range 0 7 1478 default "1" 1479 depends on MTRR_SANITIZER 1480 ---help--- 1481 mtrr cleanup spare entries default, it can be changed via 1482 mtrr_spare_reg_nr=N on the kernel command line. 1483 1484config X86_PAT 1485 def_bool y 1486 prompt "x86 PAT support" if EXPERT 1487 depends on MTRR 1488 ---help--- 1489 Use PAT attributes to setup page level cache control. 1490 1491 PATs are the modern equivalents of MTRRs and are much more 1492 flexible than MTRRs. 1493 1494 Say N here if you see bootup problems (boot crash, boot hang, 1495 spontaneous reboots) or a non-working video driver. 1496 1497 If unsure, say Y. 1498 1499config ARCH_USES_PG_UNCACHED 1500 def_bool y 1501 depends on X86_PAT 1502 1503config ARCH_RANDOM 1504 def_bool y 1505 prompt "x86 architectural random number generator" if EXPERT 1506 ---help--- 1507 Enable the x86 architectural RDRAND instruction 1508 (Intel Bull Mountain technology) to generate random numbers. 1509 If supported, this is a high bandwidth, cryptographically 1510 secure hardware random number generator. 1511 1512config X86_SMAP 1513 def_bool y 1514 prompt "Supervisor Mode Access Prevention" if EXPERT 1515 ---help--- 1516 Supervisor Mode Access Prevention (SMAP) is a security 1517 feature in newer Intel processors. There is a small 1518 performance cost if this enabled and turned on; there is 1519 also a small increase in the kernel size if this is enabled. 1520 1521 If unsure, say Y. 1522 1523config EFI 1524 bool "EFI runtime service support" 1525 depends on ACPI 1526 select UCS2_STRING 1527 select EFI_RUNTIME_WRAPPERS 1528 ---help--- 1529 This enables the kernel to use EFI runtime services that are 1530 available (such as the EFI variable services). 1531 1532 This option is only useful on systems that have EFI firmware. 1533 In addition, you should use the latest ELILO loader available 1534 at <http://elilo.sourceforge.net> in order to take advantage 1535 of EFI runtime services. However, even with this option, the 1536 resultant kernel should continue to boot on existing non-EFI 1537 platforms. 1538 1539config EFI_STUB 1540 bool "EFI stub support" 1541 depends on EFI 1542 ---help--- 1543 This kernel feature allows a bzImage to be loaded directly 1544 by EFI firmware without the use of a bootloader. 1545 1546 See Documentation/efi-stub.txt for more information. 1547 1548config EFI_MIXED 1549 bool "EFI mixed-mode support" 1550 depends on EFI_STUB && X86_64 1551 ---help--- 1552 Enabling this feature allows a 64-bit kernel to be booted 1553 on a 32-bit firmware, provided that your CPU supports 64-bit 1554 mode. 1555 1556 Note that it is not possible to boot a mixed-mode enabled 1557 kernel via the EFI boot stub - a bootloader that supports 1558 the EFI handover protocol must be used. 1559 1560 If unsure, say N. 1561 1562config SECCOMP 1563 def_bool y 1564 prompt "Enable seccomp to safely compute untrusted bytecode" 1565 ---help--- 1566 This kernel feature is useful for number crunching applications 1567 that may need to compute untrusted bytecode during their 1568 execution. By using pipes or other transports made available to 1569 the process as file descriptors supporting the read/write 1570 syscalls, it's possible to isolate those applications in 1571 their own address space using seccomp. Once seccomp is 1572 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1573 and the task is only allowed to execute a few safe syscalls 1574 defined by each seccomp mode. 1575 1576 If unsure, say Y. Only embedded should say N here. 1577 1578source kernel/Kconfig.hz 1579 1580config KEXEC 1581 bool "kexec system call" 1582 ---help--- 1583 kexec is a system call that implements the ability to shutdown your 1584 current kernel, and to start another kernel. It is like a reboot 1585 but it is independent of the system firmware. And like a reboot 1586 you can start any kernel with it, not just Linux. 1587 1588 The name comes from the similarity to the exec system call. 1589 1590 It is an ongoing process to be certain the hardware in a machine 1591 is properly shutdown, so do not be surprised if this code does not 1592 initially work for you. As of this writing the exact hardware 1593 interface is strongly in flux, so no good recommendation can be 1594 made. 1595 1596config CRASH_DUMP 1597 bool "kernel crash dumps" 1598 depends on X86_64 || (X86_32 && HIGHMEM) 1599 ---help--- 1600 Generate crash dump after being started by kexec. 1601 This should be normally only set in special crash dump kernels 1602 which are loaded in the main kernel with kexec-tools into 1603 a specially reserved region and then later executed after 1604 a crash by kdump/kexec. The crash dump kernel must be compiled 1605 to a memory address not used by the main kernel or BIOS using 1606 PHYSICAL_START, or it must be built as a relocatable image 1607 (CONFIG_RELOCATABLE=y). 1608 For more details see Documentation/kdump/kdump.txt 1609 1610config KEXEC_JUMP 1611 bool "kexec jump" 1612 depends on KEXEC && HIBERNATION 1613 ---help--- 1614 Jump between original kernel and kexeced kernel and invoke 1615 code in physical address mode via KEXEC 1616 1617config PHYSICAL_START 1618 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1619 default "0x1000000" 1620 ---help--- 1621 This gives the physical address where the kernel is loaded. 1622 1623 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1624 bzImage will decompress itself to above physical address and 1625 run from there. Otherwise, bzImage will run from the address where 1626 it has been loaded by the boot loader and will ignore above physical 1627 address. 1628 1629 In normal kdump cases one does not have to set/change this option 1630 as now bzImage can be compiled as a completely relocatable image 1631 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1632 address. This option is mainly useful for the folks who don't want 1633 to use a bzImage for capturing the crash dump and want to use a 1634 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1635 to be specifically compiled to run from a specific memory area 1636 (normally a reserved region) and this option comes handy. 1637 1638 So if you are using bzImage for capturing the crash dump, 1639 leave the value here unchanged to 0x1000000 and set 1640 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1641 for capturing the crash dump change this value to start of 1642 the reserved region. In other words, it can be set based on 1643 the "X" value as specified in the "crashkernel=YM@XM" 1644 command line boot parameter passed to the panic-ed 1645 kernel. Please take a look at Documentation/kdump/kdump.txt 1646 for more details about crash dumps. 1647 1648 Usage of bzImage for capturing the crash dump is recommended as 1649 one does not have to build two kernels. Same kernel can be used 1650 as production kernel and capture kernel. Above option should have 1651 gone away after relocatable bzImage support is introduced. But it 1652 is present because there are users out there who continue to use 1653 vmlinux for dump capture. This option should go away down the 1654 line. 1655 1656 Don't change this unless you know what you are doing. 1657 1658config RELOCATABLE 1659 bool "Build a relocatable kernel" 1660 default y 1661 ---help--- 1662 This builds a kernel image that retains relocation information 1663 so it can be loaded someplace besides the default 1MB. 1664 The relocations tend to make the kernel binary about 10% larger, 1665 but are discarded at runtime. 1666 1667 One use is for the kexec on panic case where the recovery kernel 1668 must live at a different physical address than the primary 1669 kernel. 1670 1671 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1672 it has been loaded at and the compile time physical address 1673 (CONFIG_PHYSICAL_START) is used as the minimum location. 1674 1675config RANDOMIZE_BASE 1676 bool "Randomize the address of the kernel image" 1677 depends on RELOCATABLE 1678 default n 1679 ---help--- 1680 Randomizes the physical and virtual address at which the 1681 kernel image is decompressed, as a security feature that 1682 deters exploit attempts relying on knowledge of the location 1683 of kernel internals. 1684 1685 Entropy is generated using the RDRAND instruction if it is 1686 supported. If RDTSC is supported, it is used as well. If 1687 neither RDRAND nor RDTSC are supported, then randomness is 1688 read from the i8254 timer. 1689 1690 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET, 1691 and aligned according to PHYSICAL_ALIGN. Since the kernel is 1692 built using 2GiB addressing, and PHYSICAL_ALGIN must be at a 1693 minimum of 2MiB, only 10 bits of entropy is theoretically 1694 possible. At best, due to page table layouts, 64-bit can use 1695 9 bits of entropy and 32-bit uses 8 bits. 1696 1697 If unsure, say N. 1698 1699config RANDOMIZE_BASE_MAX_OFFSET 1700 hex "Maximum kASLR offset allowed" if EXPERT 1701 depends on RANDOMIZE_BASE 1702 range 0x0 0x20000000 if X86_32 1703 default "0x20000000" if X86_32 1704 range 0x0 0x40000000 if X86_64 1705 default "0x40000000" if X86_64 1706 ---help--- 1707 The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical 1708 memory is used to determine the maximal offset in bytes that will 1709 be applied to the kernel when kernel Address Space Layout 1710 Randomization (kASLR) is active. This must be a multiple of 1711 PHYSICAL_ALIGN. 1712 1713 On 32-bit this is limited to 512MiB by page table layouts. The 1714 default is 512MiB. 1715 1716 On 64-bit this is limited by how the kernel fixmap page table is 1717 positioned, so this cannot be larger than 1GiB currently. Without 1718 RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel 1719 and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the 1720 modules area will shrink to compensate, up to the current maximum 1721 1GiB to 1GiB split. The default is 1GiB. 1722 1723 If unsure, leave at the default value. 1724 1725# Relocation on x86 needs some additional build support 1726config X86_NEED_RELOCS 1727 def_bool y 1728 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 1729 1730config PHYSICAL_ALIGN 1731 hex "Alignment value to which kernel should be aligned" 1732 default "0x200000" 1733 range 0x2000 0x1000000 if X86_32 1734 range 0x200000 0x1000000 if X86_64 1735 ---help--- 1736 This value puts the alignment restrictions on physical address 1737 where kernel is loaded and run from. Kernel is compiled for an 1738 address which meets above alignment restriction. 1739 1740 If bootloader loads the kernel at a non-aligned address and 1741 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1742 address aligned to above value and run from there. 1743 1744 If bootloader loads the kernel at a non-aligned address and 1745 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1746 load address and decompress itself to the address it has been 1747 compiled for and run from there. The address for which kernel is 1748 compiled already meets above alignment restrictions. Hence the 1749 end result is that kernel runs from a physical address meeting 1750 above alignment restrictions. 1751 1752 On 32-bit this value must be a multiple of 0x2000. On 64-bit 1753 this value must be a multiple of 0x200000. 1754 1755 Don't change this unless you know what you are doing. 1756 1757config HOTPLUG_CPU 1758 bool "Support for hot-pluggable CPUs" 1759 depends on SMP 1760 ---help--- 1761 Say Y here to allow turning CPUs off and on. CPUs can be 1762 controlled through /sys/devices/system/cpu. 1763 ( Note: power management support will enable this option 1764 automatically on SMP systems. ) 1765 Say N if you want to disable CPU hotplug. 1766 1767config BOOTPARAM_HOTPLUG_CPU0 1768 bool "Set default setting of cpu0_hotpluggable" 1769 default n 1770 depends on HOTPLUG_CPU 1771 ---help--- 1772 Set whether default state of cpu0_hotpluggable is on or off. 1773 1774 Say Y here to enable CPU0 hotplug by default. If this switch 1775 is turned on, there is no need to give cpu0_hotplug kernel 1776 parameter and the CPU0 hotplug feature is enabled by default. 1777 1778 Please note: there are two known CPU0 dependencies if you want 1779 to enable the CPU0 hotplug feature either by this switch or by 1780 cpu0_hotplug kernel parameter. 1781 1782 First, resume from hibernate or suspend always starts from CPU0. 1783 So hibernate and suspend are prevented if CPU0 is offline. 1784 1785 Second dependency is PIC interrupts always go to CPU0. CPU0 can not 1786 offline if any interrupt can not migrate out of CPU0. There may 1787 be other CPU0 dependencies. 1788 1789 Please make sure the dependencies are under your control before 1790 you enable this feature. 1791 1792 Say N if you don't want to enable CPU0 hotplug feature by default. 1793 You still can enable the CPU0 hotplug feature at boot by kernel 1794 parameter cpu0_hotplug. 1795 1796config DEBUG_HOTPLUG_CPU0 1797 def_bool n 1798 prompt "Debug CPU0 hotplug" 1799 depends on HOTPLUG_CPU 1800 ---help--- 1801 Enabling this option offlines CPU0 (if CPU0 can be offlined) as 1802 soon as possible and boots up userspace with CPU0 offlined. User 1803 can online CPU0 back after boot time. 1804 1805 To debug CPU0 hotplug, you need to enable CPU0 offline/online 1806 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 1807 compilation or giving cpu0_hotplug kernel parameter at boot. 1808 1809 If unsure, say N. 1810 1811config COMPAT_VDSO 1812 def_bool n 1813 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 1814 depends on X86_32 || IA32_EMULATION 1815 ---help--- 1816 Certain buggy versions of glibc will crash if they are 1817 presented with a 32-bit vDSO that is not mapped at the address 1818 indicated in its segment table. 1819 1820 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 1821 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 1822 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 1823 the only released version with the bug, but OpenSUSE 9 1824 contains a buggy "glibc 2.3.2". 1825 1826 The symptom of the bug is that everything crashes on startup, saying: 1827 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 1828 1829 Saying Y here changes the default value of the vdso32 boot 1830 option from 1 to 0, which turns off the 32-bit vDSO entirely. 1831 This works around the glibc bug but hurts performance. 1832 1833 If unsure, say N: if you are compiling your own kernel, you 1834 are unlikely to be using a buggy version of glibc. 1835 1836config CMDLINE_BOOL 1837 bool "Built-in kernel command line" 1838 ---help--- 1839 Allow for specifying boot arguments to the kernel at 1840 build time. On some systems (e.g. embedded ones), it is 1841 necessary or convenient to provide some or all of the 1842 kernel boot arguments with the kernel itself (that is, 1843 to not rely on the boot loader to provide them.) 1844 1845 To compile command line arguments into the kernel, 1846 set this option to 'Y', then fill in the 1847 the boot arguments in CONFIG_CMDLINE. 1848 1849 Systems with fully functional boot loaders (i.e. non-embedded) 1850 should leave this option set to 'N'. 1851 1852config CMDLINE 1853 string "Built-in kernel command string" 1854 depends on CMDLINE_BOOL 1855 default "" 1856 ---help--- 1857 Enter arguments here that should be compiled into the kernel 1858 image and used at boot time. If the boot loader provides a 1859 command line at boot time, it is appended to this string to 1860 form the full kernel command line, when the system boots. 1861 1862 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 1863 change this behavior. 1864 1865 In most cases, the command line (whether built-in or provided 1866 by the boot loader) should specify the device for the root 1867 file system. 1868 1869config CMDLINE_OVERRIDE 1870 bool "Built-in command line overrides boot loader arguments" 1871 depends on CMDLINE_BOOL 1872 ---help--- 1873 Set this option to 'Y' to have the kernel ignore the boot loader 1874 command line, and use ONLY the built-in command line. 1875 1876 This is used to work around broken boot loaders. This should 1877 be set to 'N' under normal conditions. 1878 1879endmenu 1880 1881config ARCH_ENABLE_MEMORY_HOTPLUG 1882 def_bool y 1883 depends on X86_64 || (X86_32 && HIGHMEM) 1884 1885config ARCH_ENABLE_MEMORY_HOTREMOVE 1886 def_bool y 1887 depends on MEMORY_HOTPLUG 1888 1889config USE_PERCPU_NUMA_NODE_ID 1890 def_bool y 1891 depends on NUMA 1892 1893config ARCH_ENABLE_SPLIT_PMD_PTLOCK 1894 def_bool y 1895 depends on X86_64 || X86_PAE 1896 1897config ARCH_ENABLE_HUGEPAGE_MIGRATION 1898 def_bool y 1899 depends on X86_64 && HUGETLB_PAGE && MIGRATION 1900 1901menu "Power management and ACPI options" 1902 1903config ARCH_HIBERNATION_HEADER 1904 def_bool y 1905 depends on X86_64 && HIBERNATION 1906 1907source "kernel/power/Kconfig" 1908 1909source "drivers/acpi/Kconfig" 1910 1911source "drivers/sfi/Kconfig" 1912 1913config X86_APM_BOOT 1914 def_bool y 1915 depends on APM 1916 1917menuconfig APM 1918 tristate "APM (Advanced Power Management) BIOS support" 1919 depends on X86_32 && PM_SLEEP 1920 ---help--- 1921 APM is a BIOS specification for saving power using several different 1922 techniques. This is mostly useful for battery powered laptops with 1923 APM compliant BIOSes. If you say Y here, the system time will be 1924 reset after a RESUME operation, the /proc/apm device will provide 1925 battery status information, and user-space programs will receive 1926 notification of APM "events" (e.g. battery status change). 1927 1928 If you select "Y" here, you can disable actual use of the APM 1929 BIOS by passing the "apm=off" option to the kernel at boot time. 1930 1931 Note that the APM support is almost completely disabled for 1932 machines with more than one CPU. 1933 1934 In order to use APM, you will need supporting software. For location 1935 and more information, read <file:Documentation/power/apm-acpi.txt> 1936 and the Battery Powered Linux mini-HOWTO, available from 1937 <http://www.tldp.org/docs.html#howto>. 1938 1939 This driver does not spin down disk drives (see the hdparm(8) 1940 manpage ("man 8 hdparm") for that), and it doesn't turn off 1941 VESA-compliant "green" monitors. 1942 1943 This driver does not support the TI 4000M TravelMate and the ACER 1944 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1945 desktop machines also don't have compliant BIOSes, and this driver 1946 may cause those machines to panic during the boot phase. 1947 1948 Generally, if you don't have a battery in your machine, there isn't 1949 much point in using this driver and you should say N. If you get 1950 random kernel OOPSes or reboots that don't seem to be related to 1951 anything, try disabling/enabling this option (or disabling/enabling 1952 APM in your BIOS). 1953 1954 Some other things you should try when experiencing seemingly random, 1955 "weird" problems: 1956 1957 1) make sure that you have enough swap space and that it is 1958 enabled. 1959 2) pass the "no-hlt" option to the kernel 1960 3) switch on floating point emulation in the kernel and pass 1961 the "no387" option to the kernel 1962 4) pass the "floppy=nodma" option to the kernel 1963 5) pass the "mem=4M" option to the kernel (thereby disabling 1964 all but the first 4 MB of RAM) 1965 6) make sure that the CPU is not over clocked. 1966 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1967 8) disable the cache from your BIOS settings 1968 9) install a fan for the video card or exchange video RAM 1969 10) install a better fan for the CPU 1970 11) exchange RAM chips 1971 12) exchange the motherboard. 1972 1973 To compile this driver as a module, choose M here: the 1974 module will be called apm. 1975 1976if APM 1977 1978config APM_IGNORE_USER_SUSPEND 1979 bool "Ignore USER SUSPEND" 1980 ---help--- 1981 This option will ignore USER SUSPEND requests. On machines with a 1982 compliant APM BIOS, you want to say N. However, on the NEC Versa M 1983 series notebooks, it is necessary to say Y because of a BIOS bug. 1984 1985config APM_DO_ENABLE 1986 bool "Enable PM at boot time" 1987 ---help--- 1988 Enable APM features at boot time. From page 36 of the APM BIOS 1989 specification: "When disabled, the APM BIOS does not automatically 1990 power manage devices, enter the Standby State, enter the Suspend 1991 State, or take power saving steps in response to CPU Idle calls." 1992 This driver will make CPU Idle calls when Linux is idle (unless this 1993 feature is turned off -- see "Do CPU IDLE calls", below). This 1994 should always save battery power, but more complicated APM features 1995 will be dependent on your BIOS implementation. You may need to turn 1996 this option off if your computer hangs at boot time when using APM 1997 support, or if it beeps continuously instead of suspending. Turn 1998 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1999 T400CDT. This is off by default since most machines do fine without 2000 this feature. 2001 2002config APM_CPU_IDLE 2003 depends on CPU_IDLE 2004 bool "Make CPU Idle calls when idle" 2005 ---help--- 2006 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2007 On some machines, this can activate improved power savings, such as 2008 a slowed CPU clock rate, when the machine is idle. These idle calls 2009 are made after the idle loop has run for some length of time (e.g., 2010 333 mS). On some machines, this will cause a hang at boot time or 2011 whenever the CPU becomes idle. (On machines with more than one CPU, 2012 this option does nothing.) 2013 2014config APM_DISPLAY_BLANK 2015 bool "Enable console blanking using APM" 2016 ---help--- 2017 Enable console blanking using the APM. Some laptops can use this to 2018 turn off the LCD backlight when the screen blanker of the Linux 2019 virtual console blanks the screen. Note that this is only used by 2020 the virtual console screen blanker, and won't turn off the backlight 2021 when using the X Window system. This also doesn't have anything to 2022 do with your VESA-compliant power-saving monitor. Further, this 2023 option doesn't work for all laptops -- it might not turn off your 2024 backlight at all, or it might print a lot of errors to the console, 2025 especially if you are using gpm. 2026 2027config APM_ALLOW_INTS 2028 bool "Allow interrupts during APM BIOS calls" 2029 ---help--- 2030 Normally we disable external interrupts while we are making calls to 2031 the APM BIOS as a measure to lessen the effects of a badly behaving 2032 BIOS implementation. The BIOS should reenable interrupts if it 2033 needs to. Unfortunately, some BIOSes do not -- especially those in 2034 many of the newer IBM Thinkpads. If you experience hangs when you 2035 suspend, try setting this to Y. Otherwise, say N. 2036 2037endif # APM 2038 2039source "drivers/cpufreq/Kconfig" 2040 2041source "drivers/cpuidle/Kconfig" 2042 2043source "drivers/idle/Kconfig" 2044 2045endmenu 2046 2047 2048menu "Bus options (PCI etc.)" 2049 2050config PCI 2051 bool "PCI support" 2052 default y 2053 ---help--- 2054 Find out whether you have a PCI motherboard. PCI is the name of a 2055 bus system, i.e. the way the CPU talks to the other stuff inside 2056 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2057 VESA. If you have PCI, say Y, otherwise N. 2058 2059choice 2060 prompt "PCI access mode" 2061 depends on X86_32 && PCI 2062 default PCI_GOANY 2063 ---help--- 2064 On PCI systems, the BIOS can be used to detect the PCI devices and 2065 determine their configuration. However, some old PCI motherboards 2066 have BIOS bugs and may crash if this is done. Also, some embedded 2067 PCI-based systems don't have any BIOS at all. Linux can also try to 2068 detect the PCI hardware directly without using the BIOS. 2069 2070 With this option, you can specify how Linux should detect the 2071 PCI devices. If you choose "BIOS", the BIOS will be used, 2072 if you choose "Direct", the BIOS won't be used, and if you 2073 choose "MMConfig", then PCI Express MMCONFIG will be used. 2074 If you choose "Any", the kernel will try MMCONFIG, then the 2075 direct access method and falls back to the BIOS if that doesn't 2076 work. If unsure, go with the default, which is "Any". 2077 2078config PCI_GOBIOS 2079 bool "BIOS" 2080 2081config PCI_GOMMCONFIG 2082 bool "MMConfig" 2083 2084config PCI_GODIRECT 2085 bool "Direct" 2086 2087config PCI_GOOLPC 2088 bool "OLPC XO-1" 2089 depends on OLPC 2090 2091config PCI_GOANY 2092 bool "Any" 2093 2094endchoice 2095 2096config PCI_BIOS 2097 def_bool y 2098 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2099 2100# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2101config PCI_DIRECT 2102 def_bool y 2103 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2104 2105config PCI_MMCONFIG 2106 def_bool y 2107 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2108 2109config PCI_OLPC 2110 def_bool y 2111 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 2112 2113config PCI_XEN 2114 def_bool y 2115 depends on PCI && XEN 2116 select SWIOTLB_XEN 2117 2118config PCI_DOMAINS 2119 def_bool y 2120 depends on PCI 2121 2122config PCI_MMCONFIG 2123 bool "Support mmconfig PCI config space access" 2124 depends on X86_64 && PCI && ACPI 2125 2126config PCI_CNB20LE_QUIRK 2127 bool "Read CNB20LE Host Bridge Windows" if EXPERT 2128 depends on PCI 2129 help 2130 Read the PCI windows out of the CNB20LE host bridge. This allows 2131 PCI hotplug to work on systems with the CNB20LE chipset which do 2132 not have ACPI. 2133 2134 There's no public spec for this chipset, and this functionality 2135 is known to be incomplete. 2136 2137 You should say N unless you know you need this. 2138 2139source "drivers/pci/pcie/Kconfig" 2140 2141source "drivers/pci/Kconfig" 2142 2143# x86_64 have no ISA slots, but can have ISA-style DMA. 2144config ISA_DMA_API 2145 bool "ISA-style DMA support" if (X86_64 && EXPERT) 2146 default y 2147 help 2148 Enables ISA-style DMA support for devices requiring such controllers. 2149 If unsure, say Y. 2150 2151if X86_32 2152 2153config ISA 2154 bool "ISA support" 2155 ---help--- 2156 Find out whether you have ISA slots on your motherboard. ISA is the 2157 name of a bus system, i.e. the way the CPU talks to the other stuff 2158 inside your box. Other bus systems are PCI, EISA, MicroChannel 2159 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2160 newer boards don't support it. If you have ISA, say Y, otherwise N. 2161 2162config EISA 2163 bool "EISA support" 2164 depends on ISA 2165 ---help--- 2166 The Extended Industry Standard Architecture (EISA) bus was 2167 developed as an open alternative to the IBM MicroChannel bus. 2168 2169 The EISA bus provided some of the features of the IBM MicroChannel 2170 bus while maintaining backward compatibility with cards made for 2171 the older ISA bus. The EISA bus saw limited use between 1988 and 2172 1995 when it was made obsolete by the PCI bus. 2173 2174 Say Y here if you are building a kernel for an EISA-based machine. 2175 2176 Otherwise, say N. 2177 2178source "drivers/eisa/Kconfig" 2179 2180config SCx200 2181 tristate "NatSemi SCx200 support" 2182 ---help--- 2183 This provides basic support for National Semiconductor's 2184 (now AMD's) Geode processors. The driver probes for the 2185 PCI-IDs of several on-chip devices, so its a good dependency 2186 for other scx200_* drivers. 2187 2188 If compiled as a module, the driver is named scx200. 2189 2190config SCx200HR_TIMER 2191 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2192 depends on SCx200 2193 default y 2194 ---help--- 2195 This driver provides a clocksource built upon the on-chip 2196 27MHz high-resolution timer. Its also a workaround for 2197 NSC Geode SC-1100's buggy TSC, which loses time when the 2198 processor goes idle (as is done by the scheduler). The 2199 other workaround is idle=poll boot option. 2200 2201config OLPC 2202 bool "One Laptop Per Child support" 2203 depends on !X86_PAE 2204 select GPIOLIB 2205 select OF 2206 select OF_PROMTREE 2207 select IRQ_DOMAIN 2208 ---help--- 2209 Add support for detecting the unique features of the OLPC 2210 XO hardware. 2211 2212config OLPC_XO1_PM 2213 bool "OLPC XO-1 Power Management" 2214 depends on OLPC && MFD_CS5535 && PM_SLEEP 2215 select MFD_CORE 2216 ---help--- 2217 Add support for poweroff and suspend of the OLPC XO-1 laptop. 2218 2219config OLPC_XO1_RTC 2220 bool "OLPC XO-1 Real Time Clock" 2221 depends on OLPC_XO1_PM && RTC_DRV_CMOS 2222 ---help--- 2223 Add support for the XO-1 real time clock, which can be used as a 2224 programmable wakeup source. 2225 2226config OLPC_XO1_SCI 2227 bool "OLPC XO-1 SCI extras" 2228 depends on OLPC && OLPC_XO1_PM 2229 depends on INPUT=y 2230 select POWER_SUPPLY 2231 select GPIO_CS5535 2232 select MFD_CORE 2233 ---help--- 2234 Add support for SCI-based features of the OLPC XO-1 laptop: 2235 - EC-driven system wakeups 2236 - Power button 2237 - Ebook switch 2238 - Lid switch 2239 - AC adapter status updates 2240 - Battery status updates 2241 2242config OLPC_XO15_SCI 2243 bool "OLPC XO-1.5 SCI extras" 2244 depends on OLPC && ACPI 2245 select POWER_SUPPLY 2246 ---help--- 2247 Add support for SCI-based features of the OLPC XO-1.5 laptop: 2248 - EC-driven system wakeups 2249 - AC adapter status updates 2250 - Battery status updates 2251 2252config ALIX 2253 bool "PCEngines ALIX System Support (LED setup)" 2254 select GPIOLIB 2255 ---help--- 2256 This option enables system support for the PCEngines ALIX. 2257 At present this just sets up LEDs for GPIO control on 2258 ALIX2/3/6 boards. However, other system specific setup should 2259 get added here. 2260 2261 Note: You must still enable the drivers for GPIO and LED support 2262 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2263 2264 Note: You have to set alix.force=1 for boards with Award BIOS. 2265 2266config NET5501 2267 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2268 select GPIOLIB 2269 ---help--- 2270 This option enables system support for the Soekris Engineering net5501. 2271 2272config GEOS 2273 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 2274 select GPIOLIB 2275 depends on DMI 2276 ---help--- 2277 This option enables system support for the Traverse Technologies GEOS. 2278 2279config TS5500 2280 bool "Technologic Systems TS-5500 platform support" 2281 depends on MELAN 2282 select CHECK_SIGNATURE 2283 select NEW_LEDS 2284 select LEDS_CLASS 2285 ---help--- 2286 This option enables system support for the Technologic Systems TS-5500. 2287 2288endif # X86_32 2289 2290config AMD_NB 2291 def_bool y 2292 depends on CPU_SUP_AMD && PCI 2293 2294source "drivers/pcmcia/Kconfig" 2295 2296source "drivers/pci/hotplug/Kconfig" 2297 2298config RAPIDIO 2299 tristate "RapidIO support" 2300 depends on PCI 2301 default n 2302 help 2303 If enabled this option will include drivers and the core 2304 infrastructure code to support RapidIO interconnect devices. 2305 2306source "drivers/rapidio/Kconfig" 2307 2308config X86_SYSFB 2309 bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2310 help 2311 Firmwares often provide initial graphics framebuffers so the BIOS, 2312 bootloader or kernel can show basic video-output during boot for 2313 user-guidance and debugging. Historically, x86 used the VESA BIOS 2314 Extensions and EFI-framebuffers for this, which are mostly limited 2315 to x86. 2316 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2317 framebuffers so the new generic system-framebuffer drivers can be 2318 used on x86. If the framebuffer is not compatible with the generic 2319 modes, it is adverticed as fallback platform framebuffer so legacy 2320 drivers like efifb, vesafb and uvesafb can pick it up. 2321 If this option is not selected, all system framebuffers are always 2322 marked as fallback platform framebuffers as usual. 2323 2324 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2325 not be able to pick up generic system framebuffers if this option 2326 is selected. You are highly encouraged to enable simplefb as 2327 replacement if you select this option. simplefb can correctly deal 2328 with generic system framebuffers. But you should still keep vesafb 2329 and others enabled as fallback if a system framebuffer is 2330 incompatible with simplefb. 2331 2332 If unsure, say Y. 2333 2334endmenu 2335 2336 2337menu "Executable file formats / Emulations" 2338 2339source "fs/Kconfig.binfmt" 2340 2341config IA32_EMULATION 2342 bool "IA32 Emulation" 2343 depends on X86_64 2344 select BINFMT_ELF 2345 select COMPAT_BINFMT_ELF 2346 select HAVE_UID16 2347 ---help--- 2348 Include code to run legacy 32-bit programs under a 2349 64-bit kernel. You should likely turn this on, unless you're 2350 100% sure that you don't have any 32-bit programs left. 2351 2352config IA32_AOUT 2353 tristate "IA32 a.out support" 2354 depends on IA32_EMULATION 2355 ---help--- 2356 Support old a.out binaries in the 32bit emulation. 2357 2358config X86_X32 2359 bool "x32 ABI for 64-bit mode" 2360 depends on X86_64 && IA32_EMULATION 2361 ---help--- 2362 Include code to run binaries for the x32 native 32-bit ABI 2363 for 64-bit processors. An x32 process gets access to the 2364 full 64-bit register file and wide data path while leaving 2365 pointers at 32 bits for smaller memory footprint. 2366 2367 You will need a recent binutils (2.22 or later) with 2368 elf32_x86_64 support enabled to compile a kernel with this 2369 option set. 2370 2371config COMPAT 2372 def_bool y 2373 depends on IA32_EMULATION || X86_X32 2374 select ARCH_WANT_OLD_COMPAT_IPC 2375 2376if COMPAT 2377config COMPAT_FOR_U64_ALIGNMENT 2378 def_bool y 2379 2380config SYSVIPC_COMPAT 2381 def_bool y 2382 depends on SYSVIPC 2383 2384config KEYS_COMPAT 2385 def_bool y 2386 depends on KEYS 2387endif 2388 2389endmenu 2390 2391 2392config HAVE_ATOMIC_IOMAP 2393 def_bool y 2394 depends on X86_32 2395 2396config X86_DEV_DMA_OPS 2397 bool 2398 depends on X86_64 || STA2X11 2399 2400config X86_DMA_REMAP 2401 bool 2402 depends on STA2X11 2403 2404config IOSF_MBI 2405 tristate 2406 default m 2407 depends on PCI 2408 2409config PMC_ATOM 2410 def_bool y 2411 depends on PCI 2412 2413source "net/Kconfig" 2414 2415source "drivers/Kconfig" 2416 2417source "drivers/firmware/Kconfig" 2418 2419source "fs/Kconfig" 2420 2421source "arch/x86/Kconfig.debug" 2422 2423source "security/Kconfig" 2424 2425source "crypto/Kconfig" 2426 2427source "arch/x86/kvm/Kconfig" 2428 2429source "lib/Kconfig" 2430