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 select X86_DEV_DMA_OPS 16 17### Arch settings 18config X86 19 def_bool y 20 select HAVE_AOUT if X86_32 21 select HAVE_UNSTABLE_SCHED_CLOCK 22 select HAVE_IDE 23 select HAVE_OPROFILE 24 select HAVE_PCSPKR_PLATFORM 25 select HAVE_PERF_EVENTS 26 select HAVE_IRQ_WORK 27 select HAVE_IOREMAP_PROT 28 select HAVE_KPROBES 29 select HAVE_MEMBLOCK 30 select HAVE_MEMBLOCK_NODE_MAP 31 select ARCH_DISCARD_MEMBLOCK 32 select ARCH_WANT_OPTIONAL_GPIOLIB 33 select ARCH_WANT_FRAME_POINTERS 34 select HAVE_DMA_ATTRS 35 select HAVE_DMA_CONTIGUOUS if !SWIOTLB 36 select HAVE_KRETPROBES 37 select HAVE_OPTPROBES 38 select HAVE_FTRACE_MCOUNT_RECORD 39 select HAVE_C_RECORDMCOUNT 40 select HAVE_DYNAMIC_FTRACE 41 select HAVE_FUNCTION_TRACER 42 select HAVE_FUNCTION_GRAPH_TRACER 43 select HAVE_FUNCTION_GRAPH_FP_TEST 44 select HAVE_FUNCTION_TRACE_MCOUNT_TEST 45 select HAVE_SYSCALL_TRACEPOINTS 46 select HAVE_KVM 47 select HAVE_ARCH_KGDB 48 select HAVE_ARCH_TRACEHOOK 49 select HAVE_GENERIC_DMA_COHERENT if X86_32 50 select HAVE_EFFICIENT_UNALIGNED_ACCESS 51 select USER_STACKTRACE_SUPPORT 52 select HAVE_REGS_AND_STACK_ACCESS_API 53 select HAVE_DMA_API_DEBUG 54 select HAVE_KERNEL_GZIP 55 select HAVE_KERNEL_BZIP2 56 select HAVE_KERNEL_LZMA 57 select HAVE_KERNEL_XZ 58 select HAVE_KERNEL_LZO 59 select HAVE_HW_BREAKPOINT 60 select HAVE_MIXED_BREAKPOINTS_REGS 61 select PERF_EVENTS 62 select HAVE_PERF_EVENTS_NMI 63 select ANON_INODES 64 select HAVE_ALIGNED_STRUCT_PAGE if SLUB && !M386 65 select HAVE_CMPXCHG_LOCAL if !M386 66 select HAVE_CMPXCHG_DOUBLE 67 select HAVE_ARCH_KMEMCHECK 68 select HAVE_USER_RETURN_NOTIFIER 69 select ARCH_BINFMT_ELF_RANDOMIZE_PIE 70 select HAVE_ARCH_JUMP_LABEL 71 select HAVE_TEXT_POKE_SMP 72 select HAVE_GENERIC_HARDIRQS 73 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE 74 select SPARSE_IRQ 75 select GENERIC_FIND_FIRST_BIT 76 select GENERIC_IRQ_PROBE 77 select GENERIC_PENDING_IRQ if SMP 78 select GENERIC_IRQ_SHOW 79 select GENERIC_CLOCKEVENTS_MIN_ADJUST 80 select IRQ_FORCED_THREADING 81 select USE_GENERIC_SMP_HELPERS if SMP 82 select HAVE_BPF_JIT if X86_64 83 select CLKEVT_I8253 84 select ARCH_HAVE_NMI_SAFE_CMPXCHG 85 select GENERIC_IOMAP 86 select DCACHE_WORD_ACCESS 87 select GENERIC_SMP_IDLE_THREAD 88 select ARCH_WANT_IPC_PARSE_VERSION if X86_32 89 select HAVE_ARCH_SECCOMP_FILTER 90 select BUILDTIME_EXTABLE_SORT 91 select GENERIC_CMOS_UPDATE 92 select CLOCKSOURCE_WATCHDOG 93 select GENERIC_CLOCKEVENTS 94 select ARCH_CLOCKSOURCE_DATA if X86_64 95 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 96 select GENERIC_TIME_VSYSCALL if X86_64 97 select KTIME_SCALAR if X86_32 98 select GENERIC_STRNCPY_FROM_USER 99 select GENERIC_STRNLEN_USER 100 101config INSTRUCTION_DECODER 102 def_bool (KPROBES || PERF_EVENTS || UPROBES) 103 104config OUTPUT_FORMAT 105 string 106 default "elf32-i386" if X86_32 107 default "elf64-x86-64" if X86_64 108 109config ARCH_DEFCONFIG 110 string 111 default "arch/x86/configs/i386_defconfig" if X86_32 112 default "arch/x86/configs/x86_64_defconfig" if X86_64 113 114config LOCKDEP_SUPPORT 115 def_bool y 116 117config STACKTRACE_SUPPORT 118 def_bool y 119 120config HAVE_LATENCYTOP_SUPPORT 121 def_bool y 122 123config MMU 124 def_bool y 125 126config SBUS 127 bool 128 129config NEED_DMA_MAP_STATE 130 def_bool (X86_64 || INTEL_IOMMU || DMA_API_DEBUG) 131 132config NEED_SG_DMA_LENGTH 133 def_bool y 134 135config GENERIC_ISA_DMA 136 def_bool ISA_DMA_API 137 138config GENERIC_BUG 139 def_bool y 140 depends on BUG 141 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 142 143config GENERIC_BUG_RELATIVE_POINTERS 144 bool 145 146config GENERIC_HWEIGHT 147 def_bool y 148 149config GENERIC_GPIO 150 bool 151 152config ARCH_MAY_HAVE_PC_FDC 153 def_bool ISA_DMA_API 154 155config RWSEM_GENERIC_SPINLOCK 156 def_bool !X86_XADD 157 158config RWSEM_XCHGADD_ALGORITHM 159 def_bool X86_XADD 160 161config GENERIC_CALIBRATE_DELAY 162 def_bool y 163 164config ARCH_HAS_CPU_RELAX 165 def_bool y 166 167config ARCH_HAS_DEFAULT_IDLE 168 def_bool y 169 170config ARCH_HAS_CACHE_LINE_SIZE 171 def_bool y 172 173config ARCH_HAS_CPU_AUTOPROBE 174 def_bool y 175 176config HAVE_SETUP_PER_CPU_AREA 177 def_bool y 178 179config NEED_PER_CPU_EMBED_FIRST_CHUNK 180 def_bool y 181 182config NEED_PER_CPU_PAGE_FIRST_CHUNK 183 def_bool y 184 185config ARCH_HIBERNATION_POSSIBLE 186 def_bool y 187 188config ARCH_SUSPEND_POSSIBLE 189 def_bool y 190 191config ZONE_DMA32 192 bool 193 default X86_64 194 195config AUDIT_ARCH 196 bool 197 default X86_64 198 199config ARCH_SUPPORTS_OPTIMIZED_INLINING 200 def_bool y 201 202config ARCH_SUPPORTS_DEBUG_PAGEALLOC 203 def_bool y 204 205config HAVE_INTEL_TXT 206 def_bool y 207 depends on EXPERIMENTAL && INTEL_IOMMU && ACPI 208 209config X86_32_SMP 210 def_bool y 211 depends on X86_32 && SMP 212 213config X86_64_SMP 214 def_bool y 215 depends on X86_64 && SMP 216 217config X86_HT 218 def_bool y 219 depends on SMP 220 221config X86_32_LAZY_GS 222 def_bool y 223 depends on X86_32 && !CC_STACKPROTECTOR 224 225config ARCH_HWEIGHT_CFLAGS 226 string 227 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32 228 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_64 229 230config ARCH_CPU_PROBE_RELEASE 231 def_bool y 232 depends on HOTPLUG_CPU 233 234config ARCH_SUPPORTS_UPROBES 235 def_bool y 236 237source "init/Kconfig" 238source "kernel/Kconfig.freezer" 239 240menu "Processor type and features" 241 242config ZONE_DMA 243 bool "DMA memory allocation support" if EXPERT 244 default y 245 help 246 DMA memory allocation support allows devices with less than 32-bit 247 addressing to allocate within the first 16MB of address space. 248 Disable if no such devices will be used. 249 250 If unsure, say Y. 251 252config SMP 253 bool "Symmetric multi-processing support" 254 ---help--- 255 This enables support for systems with more than one CPU. If you have 256 a system with only one CPU, like most personal computers, say N. If 257 you have a system with more than one CPU, say Y. 258 259 If you say N here, the kernel will run on single and multiprocessor 260 machines, but will use only one CPU of a multiprocessor machine. If 261 you say Y here, the kernel will run on many, but not all, 262 singleprocessor machines. On a singleprocessor machine, the kernel 263 will run faster if you say N here. 264 265 Note that if you say Y here and choose architecture "586" or 266 "Pentium" under "Processor family", the kernel will not work on 486 267 architectures. Similarly, multiprocessor kernels for the "PPro" 268 architecture may not work on all Pentium based boards. 269 270 People using multiprocessor machines who say Y here should also say 271 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 272 Management" code will be disabled if you say Y here. 273 274 See also <file:Documentation/x86/i386/IO-APIC.txt>, 275 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 276 <http://www.tldp.org/docs.html#howto>. 277 278 If you don't know what to do here, say N. 279 280config X86_X2APIC 281 bool "Support x2apic" 282 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP 283 ---help--- 284 This enables x2apic support on CPUs that have this feature. 285 286 This allows 32-bit apic IDs (so it can support very large systems), 287 and accesses the local apic via MSRs not via mmio. 288 289 If you don't know what to do here, say N. 290 291config X86_MPPARSE 292 bool "Enable MPS table" if ACPI 293 default y 294 depends on X86_LOCAL_APIC 295 ---help--- 296 For old smp systems that do not have proper acpi support. Newer systems 297 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 298 299config X86_BIGSMP 300 bool "Support for big SMP systems with more than 8 CPUs" 301 depends on X86_32 && SMP 302 ---help--- 303 This option is needed for the systems that have more than 8 CPUs 304 305if X86_32 306config X86_EXTENDED_PLATFORM 307 bool "Support for extended (non-PC) x86 platforms" 308 default y 309 ---help--- 310 If you disable this option then the kernel will only support 311 standard PC platforms. (which covers the vast majority of 312 systems out there.) 313 314 If you enable this option then you'll be able to select support 315 for the following (non-PC) 32 bit x86 platforms: 316 AMD Elan 317 NUMAQ (IBM/Sequent) 318 RDC R-321x SoC 319 SGI 320/540 (Visual Workstation) 320 STA2X11-based (e.g. Northville) 321 Summit/EXA (IBM x440) 322 Unisys ES7000 IA32 series 323 Moorestown MID devices 324 325 If you have one of these systems, or if you want to build a 326 generic distribution kernel, say Y here - otherwise say N. 327endif 328 329if X86_64 330config X86_EXTENDED_PLATFORM 331 bool "Support for extended (non-PC) x86 platforms" 332 default y 333 ---help--- 334 If you disable this option then the kernel will only support 335 standard PC platforms. (which covers the vast majority of 336 systems out there.) 337 338 If you enable this option then you'll be able to select support 339 for the following (non-PC) 64 bit x86 platforms: 340 Numascale NumaChip 341 ScaleMP vSMP 342 SGI Ultraviolet 343 344 If you have one of these systems, or if you want to build a 345 generic distribution kernel, say Y here - otherwise say N. 346endif 347# This is an alphabetically sorted list of 64 bit extended platforms 348# Please maintain the alphabetic order if and when there are additions 349config X86_NUMACHIP 350 bool "Numascale NumaChip" 351 depends on X86_64 352 depends on X86_EXTENDED_PLATFORM 353 depends on NUMA 354 depends on SMP 355 depends on X86_X2APIC 356 ---help--- 357 Adds support for Numascale NumaChip large-SMP systems. Needed to 358 enable more than ~168 cores. 359 If you don't have one of these, you should say N here. 360 361config X86_VSMP 362 bool "ScaleMP vSMP" 363 select PARAVIRT_GUEST 364 select PARAVIRT 365 depends on X86_64 && PCI 366 depends on X86_EXTENDED_PLATFORM 367 depends on SMP 368 ---help--- 369 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 370 supposed to run on these EM64T-based machines. Only choose this option 371 if you have one of these machines. 372 373config X86_UV 374 bool "SGI Ultraviolet" 375 depends on X86_64 376 depends on X86_EXTENDED_PLATFORM 377 depends on NUMA 378 depends on X86_X2APIC 379 ---help--- 380 This option is needed in order to support SGI Ultraviolet systems. 381 If you don't have one of these, you should say N here. 382 383# Following is an alphabetically sorted list of 32 bit extended platforms 384# Please maintain the alphabetic order if and when there are additions 385 386config X86_INTEL_CE 387 bool "CE4100 TV platform" 388 depends on PCI 389 depends on PCI_GODIRECT 390 depends on X86_32 391 depends on X86_EXTENDED_PLATFORM 392 select X86_REBOOTFIXUPS 393 select OF 394 select OF_EARLY_FLATTREE 395 select IRQ_DOMAIN 396 ---help--- 397 Select for the Intel CE media processor (CE4100) SOC. 398 This option compiles in support for the CE4100 SOC for settop 399 boxes and media devices. 400 401config X86_WANT_INTEL_MID 402 bool "Intel MID platform support" 403 depends on X86_32 404 depends on X86_EXTENDED_PLATFORM 405 ---help--- 406 Select to build a kernel capable of supporting Intel MID platform 407 systems which do not have the PCI legacy interfaces (Moorestown, 408 Medfield). If you are building for a PC class system say N here. 409 410if X86_WANT_INTEL_MID 411 412config X86_INTEL_MID 413 bool 414 415config X86_MDFLD 416 bool "Medfield MID platform" 417 depends on PCI 418 depends on PCI_GOANY 419 depends on X86_IO_APIC 420 select X86_INTEL_MID 421 select SFI 422 select DW_APB_TIMER 423 select APB_TIMER 424 select I2C 425 select SPI 426 select INTEL_SCU_IPC 427 select X86_PLATFORM_DEVICES 428 select MFD_INTEL_MSIC 429 ---help--- 430 Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin 431 Internet Device(MID) platform. 432 Unlike standard x86 PCs, Medfield does not have many legacy devices 433 nor standard legacy replacement devices/features. e.g. Medfield does 434 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports. 435 436endif 437 438config X86_RDC321X 439 bool "RDC R-321x SoC" 440 depends on X86_32 441 depends on X86_EXTENDED_PLATFORM 442 select M486 443 select X86_REBOOTFIXUPS 444 ---help--- 445 This option is needed for RDC R-321x system-on-chip, also known 446 as R-8610-(G). 447 If you don't have one of these chips, you should say N here. 448 449config X86_32_NON_STANDARD 450 bool "Support non-standard 32-bit SMP architectures" 451 depends on X86_32 && SMP 452 depends on X86_EXTENDED_PLATFORM 453 ---help--- 454 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, 455 STA2X11, default subarchitectures. It is intended for a generic 456 binary kernel. If you select them all, kernel will probe it 457 one by one and will fallback to default. 458 459# Alphabetically sorted list of Non standard 32 bit platforms 460 461config X86_NUMAQ 462 bool "NUMAQ (IBM/Sequent)" 463 depends on X86_32_NON_STANDARD 464 depends on PCI 465 select NUMA 466 select X86_MPPARSE 467 ---help--- 468 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent) 469 NUMA multiquad box. This changes the way that processors are 470 bootstrapped, and uses Clustered Logical APIC addressing mode instead 471 of Flat Logical. You will need a new lynxer.elf file to flash your 472 firmware with - send email to <Martin.Bligh@us.ibm.com>. 473 474config X86_SUPPORTS_MEMORY_FAILURE 475 def_bool y 476 # MCE code calls memory_failure(): 477 depends on X86_MCE 478 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 479 depends on !X86_NUMAQ 480 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 481 depends on X86_64 || !SPARSEMEM 482 select ARCH_SUPPORTS_MEMORY_FAILURE 483 484config X86_VISWS 485 bool "SGI 320/540 (Visual Workstation)" 486 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT 487 depends on X86_32_NON_STANDARD 488 ---help--- 489 The SGI Visual Workstation series is an IA32-based workstation 490 based on SGI systems chips with some legacy PC hardware attached. 491 492 Say Y here to create a kernel to run on the SGI 320 or 540. 493 494 A kernel compiled for the Visual Workstation will run on general 495 PCs as well. See <file:Documentation/sgi-visws.txt> for details. 496 497config STA2X11 498 bool "STA2X11 Companion Chip Support" 499 depends on X86_32_NON_STANDARD && PCI 500 select X86_DEV_DMA_OPS 501 select X86_DMA_REMAP 502 select SWIOTLB 503 select MFD_STA2X11 504 select ARCH_REQUIRE_GPIOLIB 505 default n 506 ---help--- 507 This adds support for boards based on the STA2X11 IO-Hub, 508 a.k.a. "ConneXt". The chip is used in place of the standard 509 PC chipset, so all "standard" peripherals are missing. If this 510 option is selected the kernel will still be able to boot on 511 standard PC machines. 512 513config X86_SUMMIT 514 bool "Summit/EXA (IBM x440)" 515 depends on X86_32_NON_STANDARD 516 ---help--- 517 This option is needed for IBM systems that use the Summit/EXA chipset. 518 In particular, it is needed for the x440. 519 520config X86_ES7000 521 bool "Unisys ES7000 IA32 series" 522 depends on X86_32_NON_STANDARD && X86_BIGSMP 523 ---help--- 524 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is 525 supposed to run on an IA32-based Unisys ES7000 system. 526 527config X86_32_IRIS 528 tristate "Eurobraille/Iris poweroff module" 529 depends on X86_32 530 ---help--- 531 The Iris machines from EuroBraille do not have APM or ACPI support 532 to shut themselves down properly. A special I/O sequence is 533 needed to do so, which is what this module does at 534 kernel shutdown. 535 536 This is only for Iris machines from EuroBraille. 537 538 If unused, say N. 539 540config SCHED_OMIT_FRAME_POINTER 541 def_bool y 542 prompt "Single-depth WCHAN output" 543 depends on X86 544 ---help--- 545 Calculate simpler /proc/<PID>/wchan values. If this option 546 is disabled then wchan values will recurse back to the 547 caller function. This provides more accurate wchan values, 548 at the expense of slightly more scheduling overhead. 549 550 If in doubt, say "Y". 551 552menuconfig PARAVIRT_GUEST 553 bool "Paravirtualized guest support" 554 ---help--- 555 Say Y here to get to see options related to running Linux under 556 various hypervisors. This option alone does not add any kernel code. 557 558 If you say N, all options in this submenu will be skipped and disabled. 559 560if PARAVIRT_GUEST 561 562config PARAVIRT_TIME_ACCOUNTING 563 bool "Paravirtual steal time accounting" 564 select PARAVIRT 565 default n 566 ---help--- 567 Select this option to enable fine granularity task steal time 568 accounting. Time spent executing other tasks in parallel with 569 the current vCPU is discounted from the vCPU power. To account for 570 that, there can be a small performance impact. 571 572 If in doubt, say N here. 573 574source "arch/x86/xen/Kconfig" 575 576config KVM_CLOCK 577 bool "KVM paravirtualized clock" 578 select PARAVIRT 579 select PARAVIRT_CLOCK 580 ---help--- 581 Turning on this option will allow you to run a paravirtualized clock 582 when running over the KVM hypervisor. Instead of relying on a PIT 583 (or probably other) emulation by the underlying device model, the host 584 provides the guest with timing infrastructure such as time of day, and 585 system time 586 587config KVM_GUEST 588 bool "KVM Guest support" 589 select PARAVIRT 590 ---help--- 591 This option enables various optimizations for running under the KVM 592 hypervisor. 593 594source "arch/x86/lguest/Kconfig" 595 596config PARAVIRT 597 bool "Enable paravirtualization code" 598 ---help--- 599 This changes the kernel so it can modify itself when it is run 600 under a hypervisor, potentially improving performance significantly 601 over full virtualization. However, when run without a hypervisor 602 the kernel is theoretically slower and slightly larger. 603 604config PARAVIRT_SPINLOCKS 605 bool "Paravirtualization layer for spinlocks" 606 depends on PARAVIRT && SMP && EXPERIMENTAL 607 ---help--- 608 Paravirtualized spinlocks allow a pvops backend to replace the 609 spinlock implementation with something virtualization-friendly 610 (for example, block the virtual CPU rather than spinning). 611 612 Unfortunately the downside is an up to 5% performance hit on 613 native kernels, with various workloads. 614 615 If you are unsure how to answer this question, answer N. 616 617config PARAVIRT_CLOCK 618 bool 619 620endif 621 622config PARAVIRT_DEBUG 623 bool "paravirt-ops debugging" 624 depends on PARAVIRT && DEBUG_KERNEL 625 ---help--- 626 Enable to debug paravirt_ops internals. Specifically, BUG if 627 a paravirt_op is missing when it is called. 628 629config NO_BOOTMEM 630 def_bool y 631 632config MEMTEST 633 bool "Memtest" 634 ---help--- 635 This option adds a kernel parameter 'memtest', which allows memtest 636 to be set. 637 memtest=0, mean disabled; -- default 638 memtest=1, mean do 1 test pattern; 639 ... 640 memtest=4, mean do 4 test patterns. 641 If you are unsure how to answer this question, answer N. 642 643config X86_SUMMIT_NUMA 644 def_bool y 645 depends on X86_32 && NUMA && X86_32_NON_STANDARD 646 647config X86_CYCLONE_TIMER 648 def_bool y 649 depends on X86_SUMMIT 650 651source "arch/x86/Kconfig.cpu" 652 653config HPET_TIMER 654 def_bool X86_64 655 prompt "HPET Timer Support" if X86_32 656 ---help--- 657 Use the IA-PC HPET (High Precision Event Timer) to manage 658 time in preference to the PIT and RTC, if a HPET is 659 present. 660 HPET is the next generation timer replacing legacy 8254s. 661 The HPET provides a stable time base on SMP 662 systems, unlike the TSC, but it is more expensive to access, 663 as it is off-chip. You can find the HPET spec at 664 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>. 665 666 You can safely choose Y here. However, HPET will only be 667 activated if the platform and the BIOS support this feature. 668 Otherwise the 8254 will be used for timing services. 669 670 Choose N to continue using the legacy 8254 timer. 671 672config HPET_EMULATE_RTC 673 def_bool y 674 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 675 676config APB_TIMER 677 def_bool y if X86_INTEL_MID 678 prompt "Intel MID APB Timer Support" if X86_INTEL_MID 679 select DW_APB_TIMER 680 depends on X86_INTEL_MID && SFI 681 help 682 APB timer is the replacement for 8254, HPET on X86 MID platforms. 683 The APBT provides a stable time base on SMP 684 systems, unlike the TSC, but it is more expensive to access, 685 as it is off-chip. APB timers are always running regardless of CPU 686 C states, they are used as per CPU clockevent device when possible. 687 688# Mark as expert because too many people got it wrong. 689# The code disables itself when not needed. 690config DMI 691 default y 692 bool "Enable DMI scanning" if EXPERT 693 ---help--- 694 Enabled scanning of DMI to identify machine quirks. Say Y 695 here unless you have verified that your setup is not 696 affected by entries in the DMI blacklist. Required by PNP 697 BIOS code. 698 699config GART_IOMMU 700 bool "GART IOMMU support" if EXPERT 701 default y 702 select SWIOTLB 703 depends on X86_64 && PCI && AMD_NB 704 ---help--- 705 Support for full DMA access of devices with 32bit memory access only 706 on systems with more than 3GB. This is usually needed for USB, 707 sound, many IDE/SATA chipsets and some other devices. 708 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART 709 based hardware IOMMU and a software bounce buffer based IOMMU used 710 on Intel systems and as fallback. 711 The code is only active when needed (enough memory and limited 712 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified 713 too. 714 715config CALGARY_IOMMU 716 bool "IBM Calgary IOMMU support" 717 select SWIOTLB 718 depends on X86_64 && PCI && EXPERIMENTAL 719 ---help--- 720 Support for hardware IOMMUs in IBM's xSeries x366 and x460 721 systems. Needed to run systems with more than 3GB of memory 722 properly with 32-bit PCI devices that do not support DAC 723 (Double Address Cycle). Calgary also supports bus level 724 isolation, where all DMAs pass through the IOMMU. This 725 prevents them from going anywhere except their intended 726 destination. This catches hard-to-find kernel bugs and 727 mis-behaving drivers and devices that do not use the DMA-API 728 properly to set up their DMA buffers. The IOMMU can be 729 turned off at boot time with the iommu=off parameter. 730 Normally the kernel will make the right choice by itself. 731 If unsure, say Y. 732 733config CALGARY_IOMMU_ENABLED_BY_DEFAULT 734 def_bool y 735 prompt "Should Calgary be enabled by default?" 736 depends on CALGARY_IOMMU 737 ---help--- 738 Should Calgary be enabled by default? if you choose 'y', Calgary 739 will be used (if it exists). If you choose 'n', Calgary will not be 740 used even if it exists. If you choose 'n' and would like to use 741 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 742 If unsure, say Y. 743 744# need this always selected by IOMMU for the VIA workaround 745config SWIOTLB 746 def_bool y if X86_64 747 ---help--- 748 Support for software bounce buffers used on x86-64 systems 749 which don't have a hardware IOMMU (e.g. the current generation 750 of Intel's x86-64 CPUs). Using this PCI devices which can only 751 access 32-bits of memory can be used on systems with more than 752 3 GB of memory. If unsure, say Y. 753 754config IOMMU_HELPER 755 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU) 756 757config MAXSMP 758 bool "Enable Maximum number of SMP Processors and NUMA Nodes" 759 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL 760 select CPUMASK_OFFSTACK 761 ---help--- 762 Enable maximum number of CPUS and NUMA Nodes for this architecture. 763 If unsure, say N. 764 765config NR_CPUS 766 int "Maximum number of CPUs" if SMP && !MAXSMP 767 range 2 8 if SMP && X86_32 && !X86_BIGSMP 768 range 2 512 if SMP && !MAXSMP 769 default "1" if !SMP 770 default "4096" if MAXSMP 771 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000) 772 default "8" if SMP 773 ---help--- 774 This allows you to specify the maximum number of CPUs which this 775 kernel will support. The maximum supported value is 512 and the 776 minimum value which makes sense is 2. 777 778 This is purely to save memory - each supported CPU adds 779 approximately eight kilobytes to the kernel image. 780 781config SCHED_SMT 782 bool "SMT (Hyperthreading) scheduler support" 783 depends on X86_HT 784 ---help--- 785 SMT scheduler support improves the CPU scheduler's decision making 786 when dealing with Intel Pentium 4 chips with HyperThreading at a 787 cost of slightly increased overhead in some places. If unsure say 788 N here. 789 790config SCHED_MC 791 def_bool y 792 prompt "Multi-core scheduler support" 793 depends on X86_HT 794 ---help--- 795 Multi-core scheduler support improves the CPU scheduler's decision 796 making when dealing with multi-core CPU chips at a cost of slightly 797 increased overhead in some places. If unsure say N here. 798 799config IRQ_TIME_ACCOUNTING 800 bool "Fine granularity task level IRQ time accounting" 801 default n 802 ---help--- 803 Select this option to enable fine granularity task irq time 804 accounting. This is done by reading a timestamp on each 805 transitions between softirq and hardirq state, so there can be a 806 small performance impact. 807 808 If in doubt, say N here. 809 810source "kernel/Kconfig.preempt" 811 812config X86_UP_APIC 813 bool "Local APIC support on uniprocessors" 814 depends on X86_32 && !SMP && !X86_32_NON_STANDARD 815 ---help--- 816 A local APIC (Advanced Programmable Interrupt Controller) is an 817 integrated interrupt controller in the CPU. If you have a single-CPU 818 system which has a processor with a local APIC, you can say Y here to 819 enable and use it. If you say Y here even though your machine doesn't 820 have a local APIC, then the kernel will still run with no slowdown at 821 all. The local APIC supports CPU-generated self-interrupts (timer, 822 performance counters), and the NMI watchdog which detects hard 823 lockups. 824 825config X86_UP_IOAPIC 826 bool "IO-APIC support on uniprocessors" 827 depends on X86_UP_APIC 828 ---help--- 829 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 830 SMP-capable replacement for PC-style interrupt controllers. Most 831 SMP systems and many recent uniprocessor systems have one. 832 833 If you have a single-CPU system with an IO-APIC, you can say Y here 834 to use it. If you say Y here even though your machine doesn't have 835 an IO-APIC, then the kernel will still run with no slowdown at all. 836 837config X86_LOCAL_APIC 838 def_bool y 839 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC 840 841config X86_IO_APIC 842 def_bool y 843 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC 844 845config X86_VISWS_APIC 846 def_bool y 847 depends on X86_32 && X86_VISWS 848 849config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 850 bool "Reroute for broken boot IRQs" 851 depends on X86_IO_APIC 852 ---help--- 853 This option enables a workaround that fixes a source of 854 spurious interrupts. This is recommended when threaded 855 interrupt handling is used on systems where the generation of 856 superfluous "boot interrupts" cannot be disabled. 857 858 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 859 entry in the chipset's IO-APIC is masked (as, e.g. the RT 860 kernel does during interrupt handling). On chipsets where this 861 boot IRQ generation cannot be disabled, this workaround keeps 862 the original IRQ line masked so that only the equivalent "boot 863 IRQ" is delivered to the CPUs. The workaround also tells the 864 kernel to set up the IRQ handler on the boot IRQ line. In this 865 way only one interrupt is delivered to the kernel. Otherwise 866 the spurious second interrupt may cause the kernel to bring 867 down (vital) interrupt lines. 868 869 Only affects "broken" chipsets. Interrupt sharing may be 870 increased on these systems. 871 872config X86_MCE 873 bool "Machine Check / overheating reporting" 874 ---help--- 875 Machine Check support allows the processor to notify the 876 kernel if it detects a problem (e.g. overheating, data corruption). 877 The action the kernel takes depends on the severity of the problem, 878 ranging from warning messages to halting the machine. 879 880config X86_MCE_INTEL 881 def_bool y 882 prompt "Intel MCE features" 883 depends on X86_MCE && X86_LOCAL_APIC 884 ---help--- 885 Additional support for intel specific MCE features such as 886 the thermal monitor. 887 888config X86_MCE_AMD 889 def_bool y 890 prompt "AMD MCE features" 891 depends on X86_MCE && X86_LOCAL_APIC 892 ---help--- 893 Additional support for AMD specific MCE features such as 894 the DRAM Error Threshold. 895 896config X86_ANCIENT_MCE 897 bool "Support for old Pentium 5 / WinChip machine checks" 898 depends on X86_32 && X86_MCE 899 ---help--- 900 Include support for machine check handling on old Pentium 5 or WinChip 901 systems. These typically need to be enabled explicitely on the command 902 line. 903 904config X86_MCE_THRESHOLD 905 depends on X86_MCE_AMD || X86_MCE_INTEL 906 def_bool y 907 908config X86_MCE_INJECT 909 depends on X86_MCE 910 tristate "Machine check injector support" 911 ---help--- 912 Provide support for injecting machine checks for testing purposes. 913 If you don't know what a machine check is and you don't do kernel 914 QA it is safe to say n. 915 916config X86_THERMAL_VECTOR 917 def_bool y 918 depends on X86_MCE_INTEL 919 920config VM86 921 bool "Enable VM86 support" if EXPERT 922 default y 923 depends on X86_32 924 ---help--- 925 This option is required by programs like DOSEMU to run 16-bit legacy 926 code on X86 processors. It also may be needed by software like 927 XFree86 to initialize some video cards via BIOS. Disabling this 928 option saves about 6k. 929 930config TOSHIBA 931 tristate "Toshiba Laptop support" 932 depends on X86_32 933 ---help--- 934 This adds a driver to safely access the System Management Mode of 935 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 936 not work on models with a Phoenix BIOS. The System Management Mode 937 is used to set the BIOS and power saving options on Toshiba portables. 938 939 For information on utilities to make use of this driver see the 940 Toshiba Linux utilities web site at: 941 <http://www.buzzard.org.uk/toshiba/>. 942 943 Say Y if you intend to run this kernel on a Toshiba portable. 944 Say N otherwise. 945 946config I8K 947 tristate "Dell laptop support" 948 select HWMON 949 ---help--- 950 This adds a driver to safely access the System Management Mode 951 of the CPU on the Dell Inspiron 8000. The System Management Mode 952 is used to read cpu temperature and cooling fan status and to 953 control the fans on the I8K portables. 954 955 This driver has been tested only on the Inspiron 8000 but it may 956 also work with other Dell laptops. You can force loading on other 957 models by passing the parameter `force=1' to the module. Use at 958 your own risk. 959 960 For information on utilities to make use of this driver see the 961 I8K Linux utilities web site at: 962 <http://people.debian.org/~dz/i8k/> 963 964 Say Y if you intend to run this kernel on a Dell Inspiron 8000. 965 Say N otherwise. 966 967config X86_REBOOTFIXUPS 968 bool "Enable X86 board specific fixups for reboot" 969 depends on X86_32 970 ---help--- 971 This enables chipset and/or board specific fixups to be done 972 in order to get reboot to work correctly. This is only needed on 973 some combinations of hardware and BIOS. The symptom, for which 974 this config is intended, is when reboot ends with a stalled/hung 975 system. 976 977 Currently, the only fixup is for the Geode machines using 978 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 979 980 Say Y if you want to enable the fixup. Currently, it's safe to 981 enable this option even if you don't need it. 982 Say N otherwise. 983 984config MICROCODE 985 tristate "/dev/cpu/microcode - microcode support" 986 select FW_LOADER 987 ---help--- 988 If you say Y here, you will be able to update the microcode on 989 certain Intel and AMD processors. The Intel support is for the 990 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, 991 Pentium 4, Xeon etc. The AMD support is for family 0x10 and 992 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra. 993 You will obviously need the actual microcode binary data itself 994 which is not shipped with the Linux kernel. 995 996 This option selects the general module only, you need to select 997 at least one vendor specific module as well. 998 999 To compile this driver as a module, choose M here: the 1000 module will be called microcode. 1001 1002config MICROCODE_INTEL 1003 bool "Intel microcode patch loading support" 1004 depends on MICROCODE 1005 default MICROCODE 1006 select FW_LOADER 1007 ---help--- 1008 This options enables microcode patch loading support for Intel 1009 processors. 1010 1011 For latest news and information on obtaining all the required 1012 Intel ingredients for this driver, check: 1013 <http://www.urbanmyth.org/microcode/>. 1014 1015config MICROCODE_AMD 1016 bool "AMD microcode patch loading support" 1017 depends on MICROCODE 1018 select FW_LOADER 1019 ---help--- 1020 If you select this option, microcode patch loading support for AMD 1021 processors will be enabled. 1022 1023config MICROCODE_OLD_INTERFACE 1024 def_bool y 1025 depends on MICROCODE 1026 1027config X86_MSR 1028 tristate "/dev/cpu/*/msr - Model-specific register support" 1029 ---help--- 1030 This device gives privileged processes access to the x86 1031 Model-Specific Registers (MSRs). It is a character device with 1032 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1033 MSR accesses are directed to a specific CPU on multi-processor 1034 systems. 1035 1036config X86_CPUID 1037 tristate "/dev/cpu/*/cpuid - CPU information support" 1038 ---help--- 1039 This device gives processes access to the x86 CPUID instruction to 1040 be executed on a specific processor. It is a character device 1041 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1042 /dev/cpu/31/cpuid. 1043 1044choice 1045 prompt "High Memory Support" 1046 default HIGHMEM64G if X86_NUMAQ 1047 default HIGHMEM4G 1048 depends on X86_32 1049 1050config NOHIGHMEM 1051 bool "off" 1052 depends on !X86_NUMAQ 1053 ---help--- 1054 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1055 However, the address space of 32-bit x86 processors is only 4 1056 Gigabytes large. That means that, if you have a large amount of 1057 physical memory, not all of it can be "permanently mapped" by the 1058 kernel. The physical memory that's not permanently mapped is called 1059 "high memory". 1060 1061 If you are compiling a kernel which will never run on a machine with 1062 more than 1 Gigabyte total physical RAM, answer "off" here (default 1063 choice and suitable for most users). This will result in a "3GB/1GB" 1064 split: 3GB are mapped so that each process sees a 3GB virtual memory 1065 space and the remaining part of the 4GB virtual memory space is used 1066 by the kernel to permanently map as much physical memory as 1067 possible. 1068 1069 If the machine has between 1 and 4 Gigabytes physical RAM, then 1070 answer "4GB" here. 1071 1072 If more than 4 Gigabytes is used then answer "64GB" here. This 1073 selection turns Intel PAE (Physical Address Extension) mode on. 1074 PAE implements 3-level paging on IA32 processors. PAE is fully 1075 supported by Linux, PAE mode is implemented on all recent Intel 1076 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1077 then the kernel will not boot on CPUs that don't support PAE! 1078 1079 The actual amount of total physical memory will either be 1080 auto detected or can be forced by using a kernel command line option 1081 such as "mem=256M". (Try "man bootparam" or see the documentation of 1082 your boot loader (lilo or loadlin) about how to pass options to the 1083 kernel at boot time.) 1084 1085 If unsure, say "off". 1086 1087config HIGHMEM4G 1088 bool "4GB" 1089 depends on !X86_NUMAQ 1090 ---help--- 1091 Select this if you have a 32-bit processor and between 1 and 4 1092 gigabytes of physical RAM. 1093 1094config HIGHMEM64G 1095 bool "64GB" 1096 depends on !M386 && !M486 1097 select X86_PAE 1098 ---help--- 1099 Select this if you have a 32-bit processor and more than 4 1100 gigabytes of physical RAM. 1101 1102endchoice 1103 1104choice 1105 depends on EXPERIMENTAL 1106 prompt "Memory split" if EXPERT 1107 default VMSPLIT_3G 1108 depends on X86_32 1109 ---help--- 1110 Select the desired split between kernel and user memory. 1111 1112 If the address range available to the kernel is less than the 1113 physical memory installed, the remaining memory will be available 1114 as "high memory". Accessing high memory is a little more costly 1115 than low memory, as it needs to be mapped into the kernel first. 1116 Note that increasing the kernel address space limits the range 1117 available to user programs, making the address space there 1118 tighter. Selecting anything other than the default 3G/1G split 1119 will also likely make your kernel incompatible with binary-only 1120 kernel modules. 1121 1122 If you are not absolutely sure what you are doing, leave this 1123 option alone! 1124 1125 config VMSPLIT_3G 1126 bool "3G/1G user/kernel split" 1127 config VMSPLIT_3G_OPT 1128 depends on !X86_PAE 1129 bool "3G/1G user/kernel split (for full 1G low memory)" 1130 config VMSPLIT_2G 1131 bool "2G/2G user/kernel split" 1132 config VMSPLIT_2G_OPT 1133 depends on !X86_PAE 1134 bool "2G/2G user/kernel split (for full 2G low memory)" 1135 config VMSPLIT_1G 1136 bool "1G/3G user/kernel split" 1137endchoice 1138 1139config PAGE_OFFSET 1140 hex 1141 default 0xB0000000 if VMSPLIT_3G_OPT 1142 default 0x80000000 if VMSPLIT_2G 1143 default 0x78000000 if VMSPLIT_2G_OPT 1144 default 0x40000000 if VMSPLIT_1G 1145 default 0xC0000000 1146 depends on X86_32 1147 1148config HIGHMEM 1149 def_bool y 1150 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1151 1152config X86_PAE 1153 bool "PAE (Physical Address Extension) Support" 1154 depends on X86_32 && !HIGHMEM4G 1155 ---help--- 1156 PAE is required for NX support, and furthermore enables 1157 larger swapspace support for non-overcommit purposes. It 1158 has the cost of more pagetable lookup overhead, and also 1159 consumes more pagetable space per process. 1160 1161config ARCH_PHYS_ADDR_T_64BIT 1162 def_bool X86_64 || X86_PAE 1163 1164config ARCH_DMA_ADDR_T_64BIT 1165 def_bool X86_64 || HIGHMEM64G 1166 1167config DIRECT_GBPAGES 1168 bool "Enable 1GB pages for kernel pagetables" if EXPERT 1169 default y 1170 depends on X86_64 1171 ---help--- 1172 Allow the kernel linear mapping to use 1GB pages on CPUs that 1173 support it. This can improve the kernel's performance a tiny bit by 1174 reducing TLB pressure. If in doubt, say "Y". 1175 1176# Common NUMA Features 1177config NUMA 1178 bool "Numa Memory Allocation and Scheduler Support" 1179 depends on SMP 1180 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL) 1181 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP) 1182 ---help--- 1183 Enable NUMA (Non Uniform Memory Access) support. 1184 1185 The kernel will try to allocate memory used by a CPU on the 1186 local memory controller of the CPU and add some more 1187 NUMA awareness to the kernel. 1188 1189 For 64-bit this is recommended if the system is Intel Core i7 1190 (or later), AMD Opteron, or EM64T NUMA. 1191 1192 For 32-bit this is only needed on (rare) 32-bit-only platforms 1193 that support NUMA topologies, such as NUMAQ / Summit, or if you 1194 boot a 32-bit kernel on a 64-bit NUMA platform. 1195 1196 Otherwise, you should say N. 1197 1198comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI" 1199 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI) 1200 1201config AMD_NUMA 1202 def_bool y 1203 prompt "Old style AMD Opteron NUMA detection" 1204 depends on X86_64 && NUMA && PCI 1205 ---help--- 1206 Enable AMD NUMA node topology detection. You should say Y here if 1207 you have a multi processor AMD system. This uses an old method to 1208 read the NUMA configuration directly from the builtin Northbridge 1209 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1210 which also takes priority if both are compiled in. 1211 1212config X86_64_ACPI_NUMA 1213 def_bool y 1214 prompt "ACPI NUMA detection" 1215 depends on X86_64 && NUMA && ACPI && PCI 1216 select ACPI_NUMA 1217 ---help--- 1218 Enable ACPI SRAT based node topology detection. 1219 1220# Some NUMA nodes have memory ranges that span 1221# other nodes. Even though a pfn is valid and 1222# between a node's start and end pfns, it may not 1223# reside on that node. See memmap_init_zone() 1224# for details. 1225config NODES_SPAN_OTHER_NODES 1226 def_bool y 1227 depends on X86_64_ACPI_NUMA 1228 1229config NUMA_EMU 1230 bool "NUMA emulation" 1231 depends on NUMA 1232 ---help--- 1233 Enable NUMA emulation. A flat machine will be split 1234 into virtual nodes when booted with "numa=fake=N", where N is the 1235 number of nodes. This is only useful for debugging. 1236 1237config NODES_SHIFT 1238 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1239 range 1 10 1240 default "10" if MAXSMP 1241 default "6" if X86_64 1242 default "4" if X86_NUMAQ 1243 default "3" 1244 depends on NEED_MULTIPLE_NODES 1245 ---help--- 1246 Specify the maximum number of NUMA Nodes available on the target 1247 system. Increases memory reserved to accommodate various tables. 1248 1249config HAVE_ARCH_ALLOC_REMAP 1250 def_bool y 1251 depends on X86_32 && NUMA 1252 1253config ARCH_HAVE_MEMORY_PRESENT 1254 def_bool y 1255 depends on X86_32 && DISCONTIGMEM 1256 1257config NEED_NODE_MEMMAP_SIZE 1258 def_bool y 1259 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1260 1261config ARCH_FLATMEM_ENABLE 1262 def_bool y 1263 depends on X86_32 && !NUMA 1264 1265config ARCH_DISCONTIGMEM_ENABLE 1266 def_bool y 1267 depends on NUMA && X86_32 1268 1269config ARCH_DISCONTIGMEM_DEFAULT 1270 def_bool y 1271 depends on NUMA && X86_32 1272 1273config ARCH_SPARSEMEM_ENABLE 1274 def_bool y 1275 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD 1276 select SPARSEMEM_STATIC if X86_32 1277 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1278 1279config ARCH_SPARSEMEM_DEFAULT 1280 def_bool y 1281 depends on X86_64 1282 1283config ARCH_SELECT_MEMORY_MODEL 1284 def_bool y 1285 depends on ARCH_SPARSEMEM_ENABLE 1286 1287config ARCH_MEMORY_PROBE 1288 def_bool X86_64 1289 depends on MEMORY_HOTPLUG 1290 1291config ARCH_PROC_KCORE_TEXT 1292 def_bool y 1293 depends on X86_64 && PROC_KCORE 1294 1295config ILLEGAL_POINTER_VALUE 1296 hex 1297 default 0 if X86_32 1298 default 0xdead000000000000 if X86_64 1299 1300source "mm/Kconfig" 1301 1302config HIGHPTE 1303 bool "Allocate 3rd-level pagetables from highmem" 1304 depends on HIGHMEM 1305 ---help--- 1306 The VM uses one page table entry for each page of physical memory. 1307 For systems with a lot of RAM, this can be wasteful of precious 1308 low memory. Setting this option will put user-space page table 1309 entries in high memory. 1310 1311config X86_CHECK_BIOS_CORRUPTION 1312 bool "Check for low memory corruption" 1313 ---help--- 1314 Periodically check for memory corruption in low memory, which 1315 is suspected to be caused by BIOS. Even when enabled in the 1316 configuration, it is disabled at runtime. Enable it by 1317 setting "memory_corruption_check=1" on the kernel command 1318 line. By default it scans the low 64k of memory every 60 1319 seconds; see the memory_corruption_check_size and 1320 memory_corruption_check_period parameters in 1321 Documentation/kernel-parameters.txt to adjust this. 1322 1323 When enabled with the default parameters, this option has 1324 almost no overhead, as it reserves a relatively small amount 1325 of memory and scans it infrequently. It both detects corruption 1326 and prevents it from affecting the running system. 1327 1328 It is, however, intended as a diagnostic tool; if repeatable 1329 BIOS-originated corruption always affects the same memory, 1330 you can use memmap= to prevent the kernel from using that 1331 memory. 1332 1333config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1334 bool "Set the default setting of memory_corruption_check" 1335 depends on X86_CHECK_BIOS_CORRUPTION 1336 default y 1337 ---help--- 1338 Set whether the default state of memory_corruption_check is 1339 on or off. 1340 1341config X86_RESERVE_LOW 1342 int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1343 default 64 1344 range 4 640 1345 ---help--- 1346 Specify the amount of low memory to reserve for the BIOS. 1347 1348 The first page contains BIOS data structures that the kernel 1349 must not use, so that page must always be reserved. 1350 1351 By default we reserve the first 64K of physical RAM, as a 1352 number of BIOSes are known to corrupt that memory range 1353 during events such as suspend/resume or monitor cable 1354 insertion, so it must not be used by the kernel. 1355 1356 You can set this to 4 if you are absolutely sure that you 1357 trust the BIOS to get all its memory reservations and usages 1358 right. If you know your BIOS have problems beyond the 1359 default 64K area, you can set this to 640 to avoid using the 1360 entire low memory range. 1361 1362 If you have doubts about the BIOS (e.g. suspend/resume does 1363 not work or there's kernel crashes after certain hardware 1364 hotplug events) then you might want to enable 1365 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1366 typical corruption patterns. 1367 1368 Leave this to the default value of 64 if you are unsure. 1369 1370config MATH_EMULATION 1371 bool 1372 prompt "Math emulation" if X86_32 1373 ---help--- 1374 Linux can emulate a math coprocessor (used for floating point 1375 operations) if you don't have one. 486DX and Pentium processors have 1376 a math coprocessor built in, 486SX and 386 do not, unless you added 1377 a 487DX or 387, respectively. (The messages during boot time can 1378 give you some hints here ["man dmesg"].) Everyone needs either a 1379 coprocessor or this emulation. 1380 1381 If you don't have a math coprocessor, you need to say Y here; if you 1382 say Y here even though you have a coprocessor, the coprocessor will 1383 be used nevertheless. (This behavior can be changed with the kernel 1384 command line option "no387", which comes handy if your coprocessor 1385 is broken. Try "man bootparam" or see the documentation of your boot 1386 loader (lilo or loadlin) about how to pass options to the kernel at 1387 boot time.) This means that it is a good idea to say Y here if you 1388 intend to use this kernel on different machines. 1389 1390 More information about the internals of the Linux math coprocessor 1391 emulation can be found in <file:arch/x86/math-emu/README>. 1392 1393 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1394 kernel, it won't hurt. 1395 1396config MTRR 1397 def_bool y 1398 prompt "MTRR (Memory Type Range Register) support" if EXPERT 1399 ---help--- 1400 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1401 the Memory Type Range Registers (MTRRs) may be used to control 1402 processor access to memory ranges. This is most useful if you have 1403 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1404 allows bus write transfers to be combined into a larger transfer 1405 before bursting over the PCI/AGP bus. This can increase performance 1406 of image write operations 2.5 times or more. Saying Y here creates a 1407 /proc/mtrr file which may be used to manipulate your processor's 1408 MTRRs. Typically the X server should use this. 1409 1410 This code has a reasonably generic interface so that similar 1411 control registers on other processors can be easily supported 1412 as well: 1413 1414 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1415 Registers (ARRs) which provide a similar functionality to MTRRs. For 1416 these, the ARRs are used to emulate the MTRRs. 1417 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1418 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1419 write-combining. All of these processors are supported by this code 1420 and it makes sense to say Y here if you have one of them. 1421 1422 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1423 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1424 can lead to all sorts of problems, so it's good to say Y here. 1425 1426 You can safely say Y even if your machine doesn't have MTRRs, you'll 1427 just add about 9 KB to your kernel. 1428 1429 See <file:Documentation/x86/mtrr.txt> for more information. 1430 1431config MTRR_SANITIZER 1432 def_bool y 1433 prompt "MTRR cleanup support" 1434 depends on MTRR 1435 ---help--- 1436 Convert MTRR layout from continuous to discrete, so X drivers can 1437 add writeback entries. 1438 1439 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1440 The largest mtrr entry size for a continuous block can be set with 1441 mtrr_chunk_size. 1442 1443 If unsure, say Y. 1444 1445config MTRR_SANITIZER_ENABLE_DEFAULT 1446 int "MTRR cleanup enable value (0-1)" 1447 range 0 1 1448 default "0" 1449 depends on MTRR_SANITIZER 1450 ---help--- 1451 Enable mtrr cleanup default value 1452 1453config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1454 int "MTRR cleanup spare reg num (0-7)" 1455 range 0 7 1456 default "1" 1457 depends on MTRR_SANITIZER 1458 ---help--- 1459 mtrr cleanup spare entries default, it can be changed via 1460 mtrr_spare_reg_nr=N on the kernel command line. 1461 1462config X86_PAT 1463 def_bool y 1464 prompt "x86 PAT support" if EXPERT 1465 depends on MTRR 1466 ---help--- 1467 Use PAT attributes to setup page level cache control. 1468 1469 PATs are the modern equivalents of MTRRs and are much more 1470 flexible than MTRRs. 1471 1472 Say N here if you see bootup problems (boot crash, boot hang, 1473 spontaneous reboots) or a non-working video driver. 1474 1475 If unsure, say Y. 1476 1477config ARCH_USES_PG_UNCACHED 1478 def_bool y 1479 depends on X86_PAT 1480 1481config ARCH_RANDOM 1482 def_bool y 1483 prompt "x86 architectural random number generator" if EXPERT 1484 ---help--- 1485 Enable the x86 architectural RDRAND instruction 1486 (Intel Bull Mountain technology) to generate random numbers. 1487 If supported, this is a high bandwidth, cryptographically 1488 secure hardware random number generator. 1489 1490config EFI 1491 bool "EFI runtime service support" 1492 depends on ACPI 1493 ---help--- 1494 This enables the kernel to use EFI runtime services that are 1495 available (such as the EFI variable services). 1496 1497 This option is only useful on systems that have EFI firmware. 1498 In addition, you should use the latest ELILO loader available 1499 at <http://elilo.sourceforge.net> in order to take advantage 1500 of EFI runtime services. However, even with this option, the 1501 resultant kernel should continue to boot on existing non-EFI 1502 platforms. 1503 1504config EFI_STUB 1505 bool "EFI stub support" 1506 depends on EFI 1507 ---help--- 1508 This kernel feature allows a bzImage to be loaded directly 1509 by EFI firmware without the use of a bootloader. 1510 1511 See Documentation/x86/efi-stub.txt for more information. 1512 1513config SECCOMP 1514 def_bool y 1515 prompt "Enable seccomp to safely compute untrusted bytecode" 1516 ---help--- 1517 This kernel feature is useful for number crunching applications 1518 that may need to compute untrusted bytecode during their 1519 execution. By using pipes or other transports made available to 1520 the process as file descriptors supporting the read/write 1521 syscalls, it's possible to isolate those applications in 1522 their own address space using seccomp. Once seccomp is 1523 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1524 and the task is only allowed to execute a few safe syscalls 1525 defined by each seccomp mode. 1526 1527 If unsure, say Y. Only embedded should say N here. 1528 1529config CC_STACKPROTECTOR 1530 bool "Enable -fstack-protector buffer overflow detection" 1531 ---help--- 1532 This option turns on the -fstack-protector GCC feature. This 1533 feature puts, at the beginning of functions, a canary value on 1534 the stack just before the return address, and validates 1535 the value just before actually returning. Stack based buffer 1536 overflows (that need to overwrite this return address) now also 1537 overwrite the canary, which gets detected and the attack is then 1538 neutralized via a kernel panic. 1539 1540 This feature requires gcc version 4.2 or above, or a distribution 1541 gcc with the feature backported. Older versions are automatically 1542 detected and for those versions, this configuration option is 1543 ignored. (and a warning is printed during bootup) 1544 1545source kernel/Kconfig.hz 1546 1547config KEXEC 1548 bool "kexec system call" 1549 ---help--- 1550 kexec is a system call that implements the ability to shutdown your 1551 current kernel, and to start another kernel. It is like a reboot 1552 but it is independent of the system firmware. And like a reboot 1553 you can start any kernel with it, not just Linux. 1554 1555 The name comes from the similarity to the exec system call. 1556 1557 It is an ongoing process to be certain the hardware in a machine 1558 is properly shutdown, so do not be surprised if this code does not 1559 initially work for you. It may help to enable device hotplugging 1560 support. As of this writing the exact hardware interface is 1561 strongly in flux, so no good recommendation can be made. 1562 1563config CRASH_DUMP 1564 bool "kernel crash dumps" 1565 depends on X86_64 || (X86_32 && HIGHMEM) 1566 ---help--- 1567 Generate crash dump after being started by kexec. 1568 This should be normally only set in special crash dump kernels 1569 which are loaded in the main kernel with kexec-tools into 1570 a specially reserved region and then later executed after 1571 a crash by kdump/kexec. The crash dump kernel must be compiled 1572 to a memory address not used by the main kernel or BIOS using 1573 PHYSICAL_START, or it must be built as a relocatable image 1574 (CONFIG_RELOCATABLE=y). 1575 For more details see Documentation/kdump/kdump.txt 1576 1577config KEXEC_JUMP 1578 bool "kexec jump (EXPERIMENTAL)" 1579 depends on EXPERIMENTAL 1580 depends on KEXEC && HIBERNATION 1581 ---help--- 1582 Jump between original kernel and kexeced kernel and invoke 1583 code in physical address mode via KEXEC 1584 1585config PHYSICAL_START 1586 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1587 default "0x1000000" 1588 ---help--- 1589 This gives the physical address where the kernel is loaded. 1590 1591 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1592 bzImage will decompress itself to above physical address and 1593 run from there. Otherwise, bzImage will run from the address where 1594 it has been loaded by the boot loader and will ignore above physical 1595 address. 1596 1597 In normal kdump cases one does not have to set/change this option 1598 as now bzImage can be compiled as a completely relocatable image 1599 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1600 address. This option is mainly useful for the folks who don't want 1601 to use a bzImage for capturing the crash dump and want to use a 1602 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1603 to be specifically compiled to run from a specific memory area 1604 (normally a reserved region) and this option comes handy. 1605 1606 So if you are using bzImage for capturing the crash dump, 1607 leave the value here unchanged to 0x1000000 and set 1608 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1609 for capturing the crash dump change this value to start of 1610 the reserved region. In other words, it can be set based on 1611 the "X" value as specified in the "crashkernel=YM@XM" 1612 command line boot parameter passed to the panic-ed 1613 kernel. Please take a look at Documentation/kdump/kdump.txt 1614 for more details about crash dumps. 1615 1616 Usage of bzImage for capturing the crash dump is recommended as 1617 one does not have to build two kernels. Same kernel can be used 1618 as production kernel and capture kernel. Above option should have 1619 gone away after relocatable bzImage support is introduced. But it 1620 is present because there are users out there who continue to use 1621 vmlinux for dump capture. This option should go away down the 1622 line. 1623 1624 Don't change this unless you know what you are doing. 1625 1626config RELOCATABLE 1627 bool "Build a relocatable kernel" 1628 default y 1629 ---help--- 1630 This builds a kernel image that retains relocation information 1631 so it can be loaded someplace besides the default 1MB. 1632 The relocations tend to make the kernel binary about 10% larger, 1633 but are discarded at runtime. 1634 1635 One use is for the kexec on panic case where the recovery kernel 1636 must live at a different physical address than the primary 1637 kernel. 1638 1639 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1640 it has been loaded at and the compile time physical address 1641 (CONFIG_PHYSICAL_START) is ignored. 1642 1643# Relocation on x86-32 needs some additional build support 1644config X86_NEED_RELOCS 1645 def_bool y 1646 depends on X86_32 && RELOCATABLE 1647 1648config PHYSICAL_ALIGN 1649 hex "Alignment value to which kernel should be aligned" if X86_32 1650 default "0x1000000" 1651 range 0x2000 0x1000000 1652 ---help--- 1653 This value puts the alignment restrictions on physical address 1654 where kernel is loaded and run from. Kernel is compiled for an 1655 address which meets above alignment restriction. 1656 1657 If bootloader loads the kernel at a non-aligned address and 1658 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1659 address aligned to above value and run from there. 1660 1661 If bootloader loads the kernel at a non-aligned address and 1662 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1663 load address and decompress itself to the address it has been 1664 compiled for and run from there. The address for which kernel is 1665 compiled already meets above alignment restrictions. Hence the 1666 end result is that kernel runs from a physical address meeting 1667 above alignment restrictions. 1668 1669 Don't change this unless you know what you are doing. 1670 1671config HOTPLUG_CPU 1672 bool "Support for hot-pluggable CPUs" 1673 depends on SMP && HOTPLUG 1674 ---help--- 1675 Say Y here to allow turning CPUs off and on. CPUs can be 1676 controlled through /sys/devices/system/cpu. 1677 ( Note: power management support will enable this option 1678 automatically on SMP systems. ) 1679 Say N if you want to disable CPU hotplug. 1680 1681config COMPAT_VDSO 1682 def_bool y 1683 prompt "Compat VDSO support" 1684 depends on X86_32 || IA32_EMULATION 1685 ---help--- 1686 Map the 32-bit VDSO to the predictable old-style address too. 1687 1688 Say N here if you are running a sufficiently recent glibc 1689 version (2.3.3 or later), to remove the high-mapped 1690 VDSO mapping and to exclusively use the randomized VDSO. 1691 1692 If unsure, say Y. 1693 1694config CMDLINE_BOOL 1695 bool "Built-in kernel command line" 1696 ---help--- 1697 Allow for specifying boot arguments to the kernel at 1698 build time. On some systems (e.g. embedded ones), it is 1699 necessary or convenient to provide some or all of the 1700 kernel boot arguments with the kernel itself (that is, 1701 to not rely on the boot loader to provide them.) 1702 1703 To compile command line arguments into the kernel, 1704 set this option to 'Y', then fill in the 1705 the boot arguments in CONFIG_CMDLINE. 1706 1707 Systems with fully functional boot loaders (i.e. non-embedded) 1708 should leave this option set to 'N'. 1709 1710config CMDLINE 1711 string "Built-in kernel command string" 1712 depends on CMDLINE_BOOL 1713 default "" 1714 ---help--- 1715 Enter arguments here that should be compiled into the kernel 1716 image and used at boot time. If the boot loader provides a 1717 command line at boot time, it is appended to this string to 1718 form the full kernel command line, when the system boots. 1719 1720 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 1721 change this behavior. 1722 1723 In most cases, the command line (whether built-in or provided 1724 by the boot loader) should specify the device for the root 1725 file system. 1726 1727config CMDLINE_OVERRIDE 1728 bool "Built-in command line overrides boot loader arguments" 1729 depends on CMDLINE_BOOL 1730 ---help--- 1731 Set this option to 'Y' to have the kernel ignore the boot loader 1732 command line, and use ONLY the built-in command line. 1733 1734 This is used to work around broken boot loaders. This should 1735 be set to 'N' under normal conditions. 1736 1737endmenu 1738 1739config ARCH_ENABLE_MEMORY_HOTPLUG 1740 def_bool y 1741 depends on X86_64 || (X86_32 && HIGHMEM) 1742 1743config ARCH_ENABLE_MEMORY_HOTREMOVE 1744 def_bool y 1745 depends on MEMORY_HOTPLUG 1746 1747config USE_PERCPU_NUMA_NODE_ID 1748 def_bool y 1749 depends on NUMA 1750 1751menu "Power management and ACPI options" 1752 1753config ARCH_HIBERNATION_HEADER 1754 def_bool y 1755 depends on X86_64 && HIBERNATION 1756 1757source "kernel/power/Kconfig" 1758 1759source "drivers/acpi/Kconfig" 1760 1761source "drivers/sfi/Kconfig" 1762 1763config X86_APM_BOOT 1764 def_bool y 1765 depends on APM 1766 1767menuconfig APM 1768 tristate "APM (Advanced Power Management) BIOS support" 1769 depends on X86_32 && PM_SLEEP 1770 ---help--- 1771 APM is a BIOS specification for saving power using several different 1772 techniques. This is mostly useful for battery powered laptops with 1773 APM compliant BIOSes. If you say Y here, the system time will be 1774 reset after a RESUME operation, the /proc/apm device will provide 1775 battery status information, and user-space programs will receive 1776 notification of APM "events" (e.g. battery status change). 1777 1778 If you select "Y" here, you can disable actual use of the APM 1779 BIOS by passing the "apm=off" option to the kernel at boot time. 1780 1781 Note that the APM support is almost completely disabled for 1782 machines with more than one CPU. 1783 1784 In order to use APM, you will need supporting software. For location 1785 and more information, read <file:Documentation/power/apm-acpi.txt> 1786 and the Battery Powered Linux mini-HOWTO, available from 1787 <http://www.tldp.org/docs.html#howto>. 1788 1789 This driver does not spin down disk drives (see the hdparm(8) 1790 manpage ("man 8 hdparm") for that), and it doesn't turn off 1791 VESA-compliant "green" monitors. 1792 1793 This driver does not support the TI 4000M TravelMate and the ACER 1794 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1795 desktop machines also don't have compliant BIOSes, and this driver 1796 may cause those machines to panic during the boot phase. 1797 1798 Generally, if you don't have a battery in your machine, there isn't 1799 much point in using this driver and you should say N. If you get 1800 random kernel OOPSes or reboots that don't seem to be related to 1801 anything, try disabling/enabling this option (or disabling/enabling 1802 APM in your BIOS). 1803 1804 Some other things you should try when experiencing seemingly random, 1805 "weird" problems: 1806 1807 1) make sure that you have enough swap space and that it is 1808 enabled. 1809 2) pass the "no-hlt" option to the kernel 1810 3) switch on floating point emulation in the kernel and pass 1811 the "no387" option to the kernel 1812 4) pass the "floppy=nodma" option to the kernel 1813 5) pass the "mem=4M" option to the kernel (thereby disabling 1814 all but the first 4 MB of RAM) 1815 6) make sure that the CPU is not over clocked. 1816 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1817 8) disable the cache from your BIOS settings 1818 9) install a fan for the video card or exchange video RAM 1819 10) install a better fan for the CPU 1820 11) exchange RAM chips 1821 12) exchange the motherboard. 1822 1823 To compile this driver as a module, choose M here: the 1824 module will be called apm. 1825 1826if APM 1827 1828config APM_IGNORE_USER_SUSPEND 1829 bool "Ignore USER SUSPEND" 1830 ---help--- 1831 This option will ignore USER SUSPEND requests. On machines with a 1832 compliant APM BIOS, you want to say N. However, on the NEC Versa M 1833 series notebooks, it is necessary to say Y because of a BIOS bug. 1834 1835config APM_DO_ENABLE 1836 bool "Enable PM at boot time" 1837 ---help--- 1838 Enable APM features at boot time. From page 36 of the APM BIOS 1839 specification: "When disabled, the APM BIOS does not automatically 1840 power manage devices, enter the Standby State, enter the Suspend 1841 State, or take power saving steps in response to CPU Idle calls." 1842 This driver will make CPU Idle calls when Linux is idle (unless this 1843 feature is turned off -- see "Do CPU IDLE calls", below). This 1844 should always save battery power, but more complicated APM features 1845 will be dependent on your BIOS implementation. You may need to turn 1846 this option off if your computer hangs at boot time when using APM 1847 support, or if it beeps continuously instead of suspending. Turn 1848 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1849 T400CDT. This is off by default since most machines do fine without 1850 this feature. 1851 1852config APM_CPU_IDLE 1853 bool "Make CPU Idle calls when idle" 1854 ---help--- 1855 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 1856 On some machines, this can activate improved power savings, such as 1857 a slowed CPU clock rate, when the machine is idle. These idle calls 1858 are made after the idle loop has run for some length of time (e.g., 1859 333 mS). On some machines, this will cause a hang at boot time or 1860 whenever the CPU becomes idle. (On machines with more than one CPU, 1861 this option does nothing.) 1862 1863config APM_DISPLAY_BLANK 1864 bool "Enable console blanking using APM" 1865 ---help--- 1866 Enable console blanking using the APM. Some laptops can use this to 1867 turn off the LCD backlight when the screen blanker of the Linux 1868 virtual console blanks the screen. Note that this is only used by 1869 the virtual console screen blanker, and won't turn off the backlight 1870 when using the X Window system. This also doesn't have anything to 1871 do with your VESA-compliant power-saving monitor. Further, this 1872 option doesn't work for all laptops -- it might not turn off your 1873 backlight at all, or it might print a lot of errors to the console, 1874 especially if you are using gpm. 1875 1876config APM_ALLOW_INTS 1877 bool "Allow interrupts during APM BIOS calls" 1878 ---help--- 1879 Normally we disable external interrupts while we are making calls to 1880 the APM BIOS as a measure to lessen the effects of a badly behaving 1881 BIOS implementation. The BIOS should reenable interrupts if it 1882 needs to. Unfortunately, some BIOSes do not -- especially those in 1883 many of the newer IBM Thinkpads. If you experience hangs when you 1884 suspend, try setting this to Y. Otherwise, say N. 1885 1886endif # APM 1887 1888source "drivers/cpufreq/Kconfig" 1889 1890source "drivers/cpuidle/Kconfig" 1891 1892source "drivers/idle/Kconfig" 1893 1894endmenu 1895 1896 1897menu "Bus options (PCI etc.)" 1898 1899config PCI 1900 bool "PCI support" 1901 default y 1902 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC) 1903 ---help--- 1904 Find out whether you have a PCI motherboard. PCI is the name of a 1905 bus system, i.e. the way the CPU talks to the other stuff inside 1906 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 1907 VESA. If you have PCI, say Y, otherwise N. 1908 1909choice 1910 prompt "PCI access mode" 1911 depends on X86_32 && PCI 1912 default PCI_GOANY 1913 ---help--- 1914 On PCI systems, the BIOS can be used to detect the PCI devices and 1915 determine their configuration. However, some old PCI motherboards 1916 have BIOS bugs and may crash if this is done. Also, some embedded 1917 PCI-based systems don't have any BIOS at all. Linux can also try to 1918 detect the PCI hardware directly without using the BIOS. 1919 1920 With this option, you can specify how Linux should detect the 1921 PCI devices. If you choose "BIOS", the BIOS will be used, 1922 if you choose "Direct", the BIOS won't be used, and if you 1923 choose "MMConfig", then PCI Express MMCONFIG will be used. 1924 If you choose "Any", the kernel will try MMCONFIG, then the 1925 direct access method and falls back to the BIOS if that doesn't 1926 work. If unsure, go with the default, which is "Any". 1927 1928config PCI_GOBIOS 1929 bool "BIOS" 1930 1931config PCI_GOMMCONFIG 1932 bool "MMConfig" 1933 1934config PCI_GODIRECT 1935 bool "Direct" 1936 1937config PCI_GOOLPC 1938 bool "OLPC XO-1" 1939 depends on OLPC 1940 1941config PCI_GOANY 1942 bool "Any" 1943 1944endchoice 1945 1946config PCI_BIOS 1947 def_bool y 1948 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 1949 1950# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 1951config PCI_DIRECT 1952 def_bool y 1953 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 1954 1955config PCI_MMCONFIG 1956 def_bool y 1957 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 1958 1959config PCI_OLPC 1960 def_bool y 1961 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 1962 1963config PCI_XEN 1964 def_bool y 1965 depends on PCI && XEN 1966 select SWIOTLB_XEN 1967 1968config PCI_DOMAINS 1969 def_bool y 1970 depends on PCI 1971 1972config PCI_MMCONFIG 1973 bool "Support mmconfig PCI config space access" 1974 depends on X86_64 && PCI && ACPI 1975 1976config PCI_CNB20LE_QUIRK 1977 bool "Read CNB20LE Host Bridge Windows" if EXPERT 1978 default n 1979 depends on PCI && EXPERIMENTAL 1980 help 1981 Read the PCI windows out of the CNB20LE host bridge. This allows 1982 PCI hotplug to work on systems with the CNB20LE chipset which do 1983 not have ACPI. 1984 1985 There's no public spec for this chipset, and this functionality 1986 is known to be incomplete. 1987 1988 You should say N unless you know you need this. 1989 1990source "drivers/pci/pcie/Kconfig" 1991 1992source "drivers/pci/Kconfig" 1993 1994# x86_64 have no ISA slots, but can have ISA-style DMA. 1995config ISA_DMA_API 1996 bool "ISA-style DMA support" if (X86_64 && EXPERT) 1997 default y 1998 help 1999 Enables ISA-style DMA support for devices requiring such controllers. 2000 If unsure, say Y. 2001 2002if X86_32 2003 2004config ISA 2005 bool "ISA support" 2006 ---help--- 2007 Find out whether you have ISA slots on your motherboard. ISA is the 2008 name of a bus system, i.e. the way the CPU talks to the other stuff 2009 inside your box. Other bus systems are PCI, EISA, MicroChannel 2010 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2011 newer boards don't support it. If you have ISA, say Y, otherwise N. 2012 2013config EISA 2014 bool "EISA support" 2015 depends on ISA 2016 ---help--- 2017 The Extended Industry Standard Architecture (EISA) bus was 2018 developed as an open alternative to the IBM MicroChannel bus. 2019 2020 The EISA bus provided some of the features of the IBM MicroChannel 2021 bus while maintaining backward compatibility with cards made for 2022 the older ISA bus. The EISA bus saw limited use between 1988 and 2023 1995 when it was made obsolete by the PCI bus. 2024 2025 Say Y here if you are building a kernel for an EISA-based machine. 2026 2027 Otherwise, say N. 2028 2029source "drivers/eisa/Kconfig" 2030 2031config SCx200 2032 tristate "NatSemi SCx200 support" 2033 ---help--- 2034 This provides basic support for National Semiconductor's 2035 (now AMD's) Geode processors. The driver probes for the 2036 PCI-IDs of several on-chip devices, so its a good dependency 2037 for other scx200_* drivers. 2038 2039 If compiled as a module, the driver is named scx200. 2040 2041config SCx200HR_TIMER 2042 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2043 depends on SCx200 2044 default y 2045 ---help--- 2046 This driver provides a clocksource built upon the on-chip 2047 27MHz high-resolution timer. Its also a workaround for 2048 NSC Geode SC-1100's buggy TSC, which loses time when the 2049 processor goes idle (as is done by the scheduler). The 2050 other workaround is idle=poll boot option. 2051 2052config OLPC 2053 bool "One Laptop Per Child support" 2054 depends on !X86_PAE 2055 select GPIOLIB 2056 select OF 2057 select OF_PROMTREE 2058 select IRQ_DOMAIN 2059 ---help--- 2060 Add support for detecting the unique features of the OLPC 2061 XO hardware. 2062 2063config OLPC_XO1_PM 2064 bool "OLPC XO-1 Power Management" 2065 depends on OLPC && MFD_CS5535 && PM_SLEEP 2066 select MFD_CORE 2067 ---help--- 2068 Add support for poweroff and suspend of the OLPC XO-1 laptop. 2069 2070config OLPC_XO1_RTC 2071 bool "OLPC XO-1 Real Time Clock" 2072 depends on OLPC_XO1_PM && RTC_DRV_CMOS 2073 ---help--- 2074 Add support for the XO-1 real time clock, which can be used as a 2075 programmable wakeup source. 2076 2077config OLPC_XO1_SCI 2078 bool "OLPC XO-1 SCI extras" 2079 depends on OLPC && OLPC_XO1_PM 2080 select POWER_SUPPLY 2081 select GPIO_CS5535 2082 select MFD_CORE 2083 ---help--- 2084 Add support for SCI-based features of the OLPC XO-1 laptop: 2085 - EC-driven system wakeups 2086 - Power button 2087 - Ebook switch 2088 - Lid switch 2089 - AC adapter status updates 2090 - Battery status updates 2091 2092config OLPC_XO15_SCI 2093 bool "OLPC XO-1.5 SCI extras" 2094 depends on OLPC && ACPI 2095 select POWER_SUPPLY 2096 ---help--- 2097 Add support for SCI-based features of the OLPC XO-1.5 laptop: 2098 - EC-driven system wakeups 2099 - AC adapter status updates 2100 - Battery status updates 2101 2102config ALIX 2103 bool "PCEngines ALIX System Support (LED setup)" 2104 select GPIOLIB 2105 ---help--- 2106 This option enables system support for the PCEngines ALIX. 2107 At present this just sets up LEDs for GPIO control on 2108 ALIX2/3/6 boards. However, other system specific setup should 2109 get added here. 2110 2111 Note: You must still enable the drivers for GPIO and LED support 2112 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2113 2114 Note: You have to set alix.force=1 for boards with Award BIOS. 2115 2116config NET5501 2117 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2118 select GPIOLIB 2119 ---help--- 2120 This option enables system support for the Soekris Engineering net5501. 2121 2122config GEOS 2123 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 2124 select GPIOLIB 2125 depends on DMI 2126 ---help--- 2127 This option enables system support for the Traverse Technologies GEOS. 2128 2129endif # X86_32 2130 2131config AMD_NB 2132 def_bool y 2133 depends on CPU_SUP_AMD && PCI 2134 2135source "drivers/pcmcia/Kconfig" 2136 2137source "drivers/pci/hotplug/Kconfig" 2138 2139config RAPIDIO 2140 bool "RapidIO support" 2141 depends on PCI 2142 default n 2143 help 2144 If you say Y here, the kernel will include drivers and 2145 infrastructure code to support RapidIO interconnect devices. 2146 2147source "drivers/rapidio/Kconfig" 2148 2149endmenu 2150 2151 2152menu "Executable file formats / Emulations" 2153 2154source "fs/Kconfig.binfmt" 2155 2156config IA32_EMULATION 2157 bool "IA32 Emulation" 2158 depends on X86_64 2159 select COMPAT_BINFMT_ELF 2160 ---help--- 2161 Include code to run legacy 32-bit programs under a 2162 64-bit kernel. You should likely turn this on, unless you're 2163 100% sure that you don't have any 32-bit programs left. 2164 2165config IA32_AOUT 2166 tristate "IA32 a.out support" 2167 depends on IA32_EMULATION 2168 ---help--- 2169 Support old a.out binaries in the 32bit emulation. 2170 2171config X86_X32 2172 bool "x32 ABI for 64-bit mode (EXPERIMENTAL)" 2173 depends on X86_64 && IA32_EMULATION && EXPERIMENTAL 2174 ---help--- 2175 Include code to run binaries for the x32 native 32-bit ABI 2176 for 64-bit processors. An x32 process gets access to the 2177 full 64-bit register file and wide data path while leaving 2178 pointers at 32 bits for smaller memory footprint. 2179 2180 You will need a recent binutils (2.22 or later) with 2181 elf32_x86_64 support enabled to compile a kernel with this 2182 option set. 2183 2184config COMPAT 2185 def_bool y 2186 depends on IA32_EMULATION || X86_X32 2187 select ARCH_WANT_OLD_COMPAT_IPC 2188 2189config COMPAT_FOR_U64_ALIGNMENT 2190 def_bool COMPAT 2191 depends on X86_64 2192 2193config SYSVIPC_COMPAT 2194 def_bool y 2195 depends on COMPAT && SYSVIPC 2196 2197config KEYS_COMPAT 2198 bool 2199 depends on COMPAT && KEYS 2200 default y 2201 2202endmenu 2203 2204 2205config HAVE_ATOMIC_IOMAP 2206 def_bool y 2207 depends on X86_32 2208 2209config HAVE_TEXT_POKE_SMP 2210 bool 2211 select STOP_MACHINE if SMP 2212 2213config X86_DEV_DMA_OPS 2214 bool 2215 depends on X86_64 || STA2X11 2216 2217config X86_DMA_REMAP 2218 bool 2219 depends on STA2X11 2220 2221source "net/Kconfig" 2222 2223source "drivers/Kconfig" 2224 2225source "drivers/firmware/Kconfig" 2226 2227source "fs/Kconfig" 2228 2229source "arch/x86/Kconfig.debug" 2230 2231source "security/Kconfig" 2232 2233source "crypto/Kconfig" 2234 2235source "arch/x86/kvm/Kconfig" 2236 2237source "lib/Kconfig" 2238