1# Select 32 or 64 bit 2config 64BIT 3 bool "64-bit kernel" if ARCH = "x86" 4 default ARCH = "x86_64" 5 ---help--- 6 Say yes to build a 64-bit kernel - formerly known as x86_64 7 Say no to build a 32-bit kernel - formerly known as i386 8 9config X86_32 10 def_bool !64BIT 11 select CLKSRC_I8253 12 13config X86_64 14 def_bool 64BIT 15 16### Arch settings 17config X86 18 def_bool y 19 select HAVE_AOUT if X86_32 20 select HAVE_UNSTABLE_SCHED_CLOCK 21 select HAVE_IDE 22 select HAVE_OPROFILE 23 select HAVE_PCSPKR_PLATFORM 24 select HAVE_PERF_EVENTS 25 select HAVE_IRQ_WORK 26 select HAVE_IOREMAP_PROT 27 select HAVE_KPROBES 28 select HAVE_MEMBLOCK 29 select HAVE_MEMBLOCK_NODE_MAP 30 select ARCH_DISCARD_MEMBLOCK 31 select ARCH_WANT_OPTIONAL_GPIOLIB 32 select ARCH_WANT_FRAME_POINTERS 33 select HAVE_DMA_ATTRS 34 select HAVE_KRETPROBES 35 select HAVE_OPTPROBES 36 select HAVE_FTRACE_MCOUNT_RECORD 37 select HAVE_C_RECORDMCOUNT 38 select HAVE_DYNAMIC_FTRACE 39 select HAVE_FUNCTION_TRACER 40 select HAVE_FUNCTION_GRAPH_TRACER 41 select HAVE_FUNCTION_GRAPH_FP_TEST 42 select HAVE_FUNCTION_TRACE_MCOUNT_TEST 43 select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE 44 select HAVE_SYSCALL_TRACEPOINTS 45 select HAVE_KVM 46 select HAVE_ARCH_KGDB 47 select HAVE_ARCH_TRACEHOOK 48 select HAVE_GENERIC_DMA_COHERENT if X86_32 49 select HAVE_EFFICIENT_UNALIGNED_ACCESS 50 select USER_STACKTRACE_SUPPORT 51 select HAVE_REGS_AND_STACK_ACCESS_API 52 select HAVE_DMA_API_DEBUG 53 select HAVE_KERNEL_GZIP 54 select HAVE_KERNEL_BZIP2 55 select HAVE_KERNEL_LZMA 56 select HAVE_KERNEL_XZ 57 select HAVE_KERNEL_LZO 58 select HAVE_HW_BREAKPOINT 59 select HAVE_MIXED_BREAKPOINTS_REGS 60 select PERF_EVENTS 61 select HAVE_PERF_EVENTS_NMI 62 select ANON_INODES 63 select HAVE_ALIGNED_STRUCT_PAGE if SLUB && !M386 64 select HAVE_CMPXCHG_LOCAL if !M386 65 select HAVE_CMPXCHG_DOUBLE 66 select HAVE_ARCH_KMEMCHECK 67 select HAVE_USER_RETURN_NOTIFIER 68 select ARCH_BINFMT_ELF_RANDOMIZE_PIE 69 select HAVE_ARCH_JUMP_LABEL 70 select HAVE_TEXT_POKE_SMP 71 select HAVE_GENERIC_HARDIRQS 72 select HAVE_SPARSE_IRQ 73 select SPARSE_IRQ 74 select GENERIC_FIND_FIRST_BIT 75 select GENERIC_IRQ_PROBE 76 select GENERIC_PENDING_IRQ if SMP 77 select GENERIC_IRQ_SHOW 78 select GENERIC_CLOCKEVENTS_MIN_ADJUST 79 select IRQ_FORCED_THREADING 80 select USE_GENERIC_SMP_HELPERS if SMP 81 select HAVE_BPF_JIT if (X86_64 && NET) 82 select CLKEVT_I8253 83 select ARCH_HAVE_NMI_SAFE_CMPXCHG 84 select GENERIC_IOMAP 85 86config INSTRUCTION_DECODER 87 def_bool (KPROBES || PERF_EVENTS) 88 89config OUTPUT_FORMAT 90 string 91 default "elf32-i386" if X86_32 92 default "elf64-x86-64" if X86_64 93 94config ARCH_DEFCONFIG 95 string 96 default "arch/x86/configs/i386_defconfig" if X86_32 97 default "arch/x86/configs/x86_64_defconfig" if X86_64 98 99config GENERIC_CMOS_UPDATE 100 def_bool y 101 102config CLOCKSOURCE_WATCHDOG 103 def_bool y 104 105config GENERIC_CLOCKEVENTS 106 def_bool y 107 108config ARCH_CLOCKSOURCE_DATA 109 def_bool y 110 depends on X86_64 111 112config GENERIC_CLOCKEVENTS_BROADCAST 113 def_bool y 114 depends on X86_64 || (X86_32 && X86_LOCAL_APIC) 115 116config LOCKDEP_SUPPORT 117 def_bool y 118 119config STACKTRACE_SUPPORT 120 def_bool y 121 122config HAVE_LATENCYTOP_SUPPORT 123 def_bool y 124 125config MMU 126 def_bool y 127 128config SBUS 129 bool 130 131config NEED_DMA_MAP_STATE 132 def_bool (X86_64 || INTEL_IOMMU || DMA_API_DEBUG) 133 134config NEED_SG_DMA_LENGTH 135 def_bool y 136 137config GENERIC_ISA_DMA 138 def_bool ISA_DMA_API 139 140config GENERIC_BUG 141 def_bool y 142 depends on BUG 143 select GENERIC_BUG_RELATIVE_POINTERS if X86_64 144 145config GENERIC_BUG_RELATIVE_POINTERS 146 bool 147 148config GENERIC_HWEIGHT 149 def_bool y 150 151config GENERIC_GPIO 152 bool 153 154config ARCH_MAY_HAVE_PC_FDC 155 def_bool ISA_DMA_API 156 157config RWSEM_GENERIC_SPINLOCK 158 def_bool !X86_XADD 159 160config RWSEM_XCHGADD_ALGORITHM 161 def_bool X86_XADD 162 163config ARCH_HAS_CPU_IDLE_WAIT 164 def_bool y 165 166config GENERIC_CALIBRATE_DELAY 167 def_bool y 168 169config GENERIC_TIME_VSYSCALL 170 bool 171 default X86_64 172 173config ARCH_HAS_CPU_RELAX 174 def_bool y 175 176config ARCH_HAS_DEFAULT_IDLE 177 def_bool y 178 179config ARCH_HAS_CACHE_LINE_SIZE 180 def_bool y 181 182config HAVE_SETUP_PER_CPU_AREA 183 def_bool y 184 185config NEED_PER_CPU_EMBED_FIRST_CHUNK 186 def_bool y 187 188config NEED_PER_CPU_PAGE_FIRST_CHUNK 189 def_bool y 190 191config ARCH_HIBERNATION_POSSIBLE 192 def_bool y 193 194config ARCH_SUSPEND_POSSIBLE 195 def_bool y 196 197config ZONE_DMA32 198 bool 199 default X86_64 200 201config AUDIT_ARCH 202 bool 203 default X86_64 204 205config ARCH_SUPPORTS_OPTIMIZED_INLINING 206 def_bool y 207 208config ARCH_SUPPORTS_DEBUG_PAGEALLOC 209 def_bool y 210 211config HAVE_INTEL_TXT 212 def_bool y 213 depends on EXPERIMENTAL && INTEL_IOMMU && ACPI 214 215config X86_32_SMP 216 def_bool y 217 depends on X86_32 && SMP 218 219config X86_64_SMP 220 def_bool y 221 depends on X86_64 && SMP 222 223config X86_HT 224 def_bool y 225 depends on SMP 226 227config X86_32_LAZY_GS 228 def_bool y 229 depends on X86_32 && !CC_STACKPROTECTOR 230 231config ARCH_HWEIGHT_CFLAGS 232 string 233 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32 234 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_64 235 236config KTIME_SCALAR 237 def_bool X86_32 238 239config ARCH_CPU_PROBE_RELEASE 240 def_bool y 241 depends on HOTPLUG_CPU 242 243source "init/Kconfig" 244source "kernel/Kconfig.freezer" 245 246menu "Processor type and features" 247 248config ZONE_DMA 249 bool "DMA memory allocation support" if EXPERT 250 default y 251 help 252 DMA memory allocation support allows devices with less than 32-bit 253 addressing to allocate within the first 16MB of address space. 254 Disable if no such devices will be used. 255 256 If unsure, say Y. 257 258source "kernel/time/Kconfig" 259 260config SMP 261 bool "Symmetric multi-processing support" 262 ---help--- 263 This enables support for systems with more than one CPU. If you have 264 a system with only one CPU, like most personal computers, say N. If 265 you have a system with more than one CPU, say Y. 266 267 If you say N here, the kernel will run on single and multiprocessor 268 machines, but will use only one CPU of a multiprocessor machine. If 269 you say Y here, the kernel will run on many, but not all, 270 singleprocessor machines. On a singleprocessor machine, the kernel 271 will run faster if you say N here. 272 273 Note that if you say Y here and choose architecture "586" or 274 "Pentium" under "Processor family", the kernel will not work on 486 275 architectures. Similarly, multiprocessor kernels for the "PPro" 276 architecture may not work on all Pentium based boards. 277 278 People using multiprocessor machines who say Y here should also say 279 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 280 Management" code will be disabled if you say Y here. 281 282 See also <file:Documentation/x86/i386/IO-APIC.txt>, 283 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 284 <http://www.tldp.org/docs.html#howto>. 285 286 If you don't know what to do here, say N. 287 288config X86_X2APIC 289 bool "Support x2apic" 290 depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP 291 ---help--- 292 This enables x2apic support on CPUs that have this feature. 293 294 This allows 32-bit apic IDs (so it can support very large systems), 295 and accesses the local apic via MSRs not via mmio. 296 297 If you don't know what to do here, say N. 298 299config X86_MPPARSE 300 bool "Enable MPS table" if ACPI 301 default y 302 depends on X86_LOCAL_APIC 303 ---help--- 304 For old smp systems that do not have proper acpi support. Newer systems 305 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 306 307config X86_BIGSMP 308 bool "Support for big SMP systems with more than 8 CPUs" 309 depends on X86_32 && SMP 310 ---help--- 311 This option is needed for the systems that have more than 8 CPUs 312 313if X86_32 314config X86_EXTENDED_PLATFORM 315 bool "Support for extended (non-PC) x86 platforms" 316 default y 317 ---help--- 318 If you disable this option then the kernel will only support 319 standard PC platforms. (which covers the vast majority of 320 systems out there.) 321 322 If you enable this option then you'll be able to select support 323 for the following (non-PC) 32 bit x86 platforms: 324 AMD Elan 325 NUMAQ (IBM/Sequent) 326 RDC R-321x SoC 327 SGI 320/540 (Visual Workstation) 328 Summit/EXA (IBM x440) 329 Unisys ES7000 IA32 series 330 Moorestown MID devices 331 332 If you have one of these systems, or if you want to build a 333 generic distribution kernel, say Y here - otherwise say N. 334endif 335 336if X86_64 337config X86_EXTENDED_PLATFORM 338 bool "Support for extended (non-PC) x86 platforms" 339 default y 340 ---help--- 341 If you disable this option then the kernel will only support 342 standard PC platforms. (which covers the vast majority of 343 systems out there.) 344 345 If you enable this option then you'll be able to select support 346 for the following (non-PC) 64 bit x86 platforms: 347 Numascale NumaChip 348 ScaleMP vSMP 349 SGI Ultraviolet 350 351 If you have one of these systems, or if you want to build a 352 generic distribution kernel, say Y here - otherwise say N. 353endif 354# This is an alphabetically sorted list of 64 bit extended platforms 355# Please maintain the alphabetic order if and when there are additions 356config X86_NUMACHIP 357 bool "Numascale NumaChip" 358 depends on X86_64 359 depends on X86_EXTENDED_PLATFORM 360 depends on NUMA 361 depends on SMP 362 depends on X86_X2APIC 363 ---help--- 364 Adds support for Numascale NumaChip large-SMP systems. Needed to 365 enable more than ~168 cores. 366 If you don't have one of these, you should say N here. 367 368config X86_VSMP 369 bool "ScaleMP vSMP" 370 select PARAVIRT_GUEST 371 select PARAVIRT 372 depends on X86_64 && PCI 373 depends on X86_EXTENDED_PLATFORM 374 ---help--- 375 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 376 supposed to run on these EM64T-based machines. Only choose this option 377 if you have one of these machines. 378 379config X86_UV 380 bool "SGI Ultraviolet" 381 depends on X86_64 382 depends on X86_EXTENDED_PLATFORM 383 depends on NUMA 384 depends on X86_X2APIC 385 ---help--- 386 This option is needed in order to support SGI Ultraviolet systems. 387 If you don't have one of these, you should say N here. 388 389# Following is an alphabetically sorted list of 32 bit extended platforms 390# Please maintain the alphabetic order if and when there are additions 391 392config X86_INTEL_CE 393 bool "CE4100 TV platform" 394 depends on PCI 395 depends on PCI_GODIRECT 396 depends on X86_32 397 depends on X86_EXTENDED_PLATFORM 398 select X86_REBOOTFIXUPS 399 select OF 400 select OF_EARLY_FLATTREE 401 ---help--- 402 Select for the Intel CE media processor (CE4100) SOC. 403 This option compiles in support for the CE4100 SOC for settop 404 boxes and media devices. 405 406config X86_WANT_INTEL_MID 407 bool "Intel MID platform support" 408 depends on X86_32 409 depends on X86_EXTENDED_PLATFORM 410 ---help--- 411 Select to build a kernel capable of supporting Intel MID platform 412 systems which do not have the PCI legacy interfaces (Moorestown, 413 Medfield). If you are building for a PC class system say N here. 414 415if X86_WANT_INTEL_MID 416 417config X86_INTEL_MID 418 bool 419 420config X86_MRST 421 bool "Moorestown MID platform" 422 depends on PCI 423 depends on PCI_GOANY 424 depends on X86_IO_APIC 425 select X86_INTEL_MID 426 select SFI 427 select DW_APB_TIMER 428 select APB_TIMER 429 select I2C 430 select SPI 431 select INTEL_SCU_IPC 432 select X86_PLATFORM_DEVICES 433 ---help--- 434 Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin 435 Internet Device(MID) platform. Moorestown consists of two chips: 436 Lincroft (CPU core, graphics, and memory controller) and Langwell IOH. 437 Unlike standard x86 PCs, Moorestown does not have many legacy devices 438 nor standard legacy replacement devices/features. e.g. Moorestown does 439 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports. 440 441config X86_MDFLD 442 bool "Medfield MID platform" 443 depends on PCI 444 depends on PCI_GOANY 445 depends on X86_IO_APIC 446 select X86_INTEL_MID 447 select SFI 448 select DW_APB_TIMER 449 select APB_TIMER 450 select I2C 451 select SPI 452 select INTEL_SCU_IPC 453 select X86_PLATFORM_DEVICES 454 ---help--- 455 Medfield is Intel's Low Power Intel Architecture (LPIA) based Moblin 456 Internet Device(MID) platform. 457 Unlike standard x86 PCs, Medfield does not have many legacy devices 458 nor standard legacy replacement devices/features. e.g. Medfield does 459 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports. 460 461endif 462 463config X86_RDC321X 464 bool "RDC R-321x SoC" 465 depends on X86_32 466 depends on X86_EXTENDED_PLATFORM 467 select M486 468 select X86_REBOOTFIXUPS 469 ---help--- 470 This option is needed for RDC R-321x system-on-chip, also known 471 as R-8610-(G). 472 If you don't have one of these chips, you should say N here. 473 474config X86_32_NON_STANDARD 475 bool "Support non-standard 32-bit SMP architectures" 476 depends on X86_32 && SMP 477 depends on X86_EXTENDED_PLATFORM 478 ---help--- 479 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default 480 subarchitectures. It is intended for a generic binary kernel. 481 if you select them all, kernel will probe it one by one. and will 482 fallback to default. 483 484# Alphabetically sorted list of Non standard 32 bit platforms 485 486config X86_NUMAQ 487 bool "NUMAQ (IBM/Sequent)" 488 depends on X86_32_NON_STANDARD 489 depends on PCI 490 select NUMA 491 select X86_MPPARSE 492 ---help--- 493 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent) 494 NUMA multiquad box. This changes the way that processors are 495 bootstrapped, and uses Clustered Logical APIC addressing mode instead 496 of Flat Logical. You will need a new lynxer.elf file to flash your 497 firmware with - send email to <Martin.Bligh@us.ibm.com>. 498 499config X86_SUPPORTS_MEMORY_FAILURE 500 def_bool y 501 # MCE code calls memory_failure(): 502 depends on X86_MCE 503 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 504 depends on !X86_NUMAQ 505 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 506 depends on X86_64 || !SPARSEMEM 507 select ARCH_SUPPORTS_MEMORY_FAILURE 508 509config X86_VISWS 510 bool "SGI 320/540 (Visual Workstation)" 511 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT 512 depends on X86_32_NON_STANDARD 513 ---help--- 514 The SGI Visual Workstation series is an IA32-based workstation 515 based on SGI systems chips with some legacy PC hardware attached. 516 517 Say Y here to create a kernel to run on the SGI 320 or 540. 518 519 A kernel compiled for the Visual Workstation will run on general 520 PCs as well. See <file:Documentation/sgi-visws.txt> for details. 521 522config X86_SUMMIT 523 bool "Summit/EXA (IBM x440)" 524 depends on X86_32_NON_STANDARD 525 ---help--- 526 This option is needed for IBM systems that use the Summit/EXA chipset. 527 In particular, it is needed for the x440. 528 529config X86_ES7000 530 bool "Unisys ES7000 IA32 series" 531 depends on X86_32_NON_STANDARD && X86_BIGSMP 532 ---help--- 533 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is 534 supposed to run on an IA32-based Unisys ES7000 system. 535 536config X86_32_IRIS 537 tristate "Eurobraille/Iris poweroff module" 538 depends on X86_32 539 ---help--- 540 The Iris machines from EuroBraille do not have APM or ACPI support 541 to shut themselves down properly. A special I/O sequence is 542 needed to do so, which is what this module does at 543 kernel shutdown. 544 545 This is only for Iris machines from EuroBraille. 546 547 If unused, say N. 548 549config SCHED_OMIT_FRAME_POINTER 550 def_bool y 551 prompt "Single-depth WCHAN output" 552 depends on X86 553 ---help--- 554 Calculate simpler /proc/<PID>/wchan values. If this option 555 is disabled then wchan values will recurse back to the 556 caller function. This provides more accurate wchan values, 557 at the expense of slightly more scheduling overhead. 558 559 If in doubt, say "Y". 560 561menuconfig PARAVIRT_GUEST 562 bool "Paravirtualized guest support" 563 ---help--- 564 Say Y here to get to see options related to running Linux under 565 various hypervisors. This option alone does not add any kernel code. 566 567 If you say N, all options in this submenu will be skipped and disabled. 568 569if PARAVIRT_GUEST 570 571config PARAVIRT_TIME_ACCOUNTING 572 bool "Paravirtual steal time accounting" 573 select PARAVIRT 574 default n 575 ---help--- 576 Select this option to enable fine granularity task steal time 577 accounting. Time spent executing other tasks in parallel with 578 the current vCPU is discounted from the vCPU power. To account for 579 that, there can be a small performance impact. 580 581 If in doubt, say N here. 582 583source "arch/x86/xen/Kconfig" 584 585config KVM_CLOCK 586 bool "KVM paravirtualized clock" 587 select PARAVIRT 588 select PARAVIRT_CLOCK 589 ---help--- 590 Turning on this option will allow you to run a paravirtualized clock 591 when running over the KVM hypervisor. Instead of relying on a PIT 592 (or probably other) emulation by the underlying device model, the host 593 provides the guest with timing infrastructure such as time of day, and 594 system time 595 596config KVM_GUEST 597 bool "KVM Guest support" 598 select PARAVIRT 599 ---help--- 600 This option enables various optimizations for running under the KVM 601 hypervisor. 602 603source "arch/x86/lguest/Kconfig" 604 605config PARAVIRT 606 bool "Enable paravirtualization code" 607 ---help--- 608 This changes the kernel so it can modify itself when it is run 609 under a hypervisor, potentially improving performance significantly 610 over full virtualization. However, when run without a hypervisor 611 the kernel is theoretically slower and slightly larger. 612 613config PARAVIRT_SPINLOCKS 614 bool "Paravirtualization layer for spinlocks" 615 depends on PARAVIRT && SMP && EXPERIMENTAL 616 ---help--- 617 Paravirtualized spinlocks allow a pvops backend to replace the 618 spinlock implementation with something virtualization-friendly 619 (for example, block the virtual CPU rather than spinning). 620 621 Unfortunately the downside is an up to 5% performance hit on 622 native kernels, with various workloads. 623 624 If you are unsure how to answer this question, answer N. 625 626config PARAVIRT_CLOCK 627 bool 628 629endif 630 631config PARAVIRT_DEBUG 632 bool "paravirt-ops debugging" 633 depends on PARAVIRT && DEBUG_KERNEL 634 ---help--- 635 Enable to debug paravirt_ops internals. Specifically, BUG if 636 a paravirt_op is missing when it is called. 637 638config NO_BOOTMEM 639 def_bool y 640 641config MEMTEST 642 bool "Memtest" 643 ---help--- 644 This option adds a kernel parameter 'memtest', which allows memtest 645 to be set. 646 memtest=0, mean disabled; -- default 647 memtest=1, mean do 1 test pattern; 648 ... 649 memtest=4, mean do 4 test patterns. 650 If you are unsure how to answer this question, answer N. 651 652config X86_SUMMIT_NUMA 653 def_bool y 654 depends on X86_32 && NUMA && X86_32_NON_STANDARD 655 656config X86_CYCLONE_TIMER 657 def_bool y 658 depends on X86_SUMMIT 659 660source "arch/x86/Kconfig.cpu" 661 662config HPET_TIMER 663 def_bool X86_64 664 prompt "HPET Timer Support" if X86_32 665 ---help--- 666 Use the IA-PC HPET (High Precision Event Timer) to manage 667 time in preference to the PIT and RTC, if a HPET is 668 present. 669 HPET is the next generation timer replacing legacy 8254s. 670 The HPET provides a stable time base on SMP 671 systems, unlike the TSC, but it is more expensive to access, 672 as it is off-chip. You can find the HPET spec at 673 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>. 674 675 You can safely choose Y here. However, HPET will only be 676 activated if the platform and the BIOS support this feature. 677 Otherwise the 8254 will be used for timing services. 678 679 Choose N to continue using the legacy 8254 timer. 680 681config HPET_EMULATE_RTC 682 def_bool y 683 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 684 685config APB_TIMER 686 def_bool y if X86_INTEL_MID 687 prompt "Intel MID APB Timer Support" if X86_INTEL_MID 688 select DW_APB_TIMER 689 depends on X86_INTEL_MID && SFI 690 help 691 APB timer is the replacement for 8254, HPET on X86 MID platforms. 692 The APBT provides a stable time base on SMP 693 systems, unlike the TSC, but it is more expensive to access, 694 as it is off-chip. APB timers are always running regardless of CPU 695 C states, they are used as per CPU clockevent device when possible. 696 697# Mark as expert because too many people got it wrong. 698# The code disables itself when not needed. 699config DMI 700 default y 701 bool "Enable DMI scanning" if EXPERT 702 ---help--- 703 Enabled scanning of DMI to identify machine quirks. Say Y 704 here unless you have verified that your setup is not 705 affected by entries in the DMI blacklist. Required by PNP 706 BIOS code. 707 708config GART_IOMMU 709 bool "GART IOMMU support" if EXPERT 710 default y 711 select SWIOTLB 712 depends on X86_64 && PCI && AMD_NB 713 ---help--- 714 Support for full DMA access of devices with 32bit memory access only 715 on systems with more than 3GB. This is usually needed for USB, 716 sound, many IDE/SATA chipsets and some other devices. 717 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART 718 based hardware IOMMU and a software bounce buffer based IOMMU used 719 on Intel systems and as fallback. 720 The code is only active when needed (enough memory and limited 721 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified 722 too. 723 724config CALGARY_IOMMU 725 bool "IBM Calgary IOMMU support" 726 select SWIOTLB 727 depends on X86_64 && PCI && EXPERIMENTAL 728 ---help--- 729 Support for hardware IOMMUs in IBM's xSeries x366 and x460 730 systems. Needed to run systems with more than 3GB of memory 731 properly with 32-bit PCI devices that do not support DAC 732 (Double Address Cycle). Calgary also supports bus level 733 isolation, where all DMAs pass through the IOMMU. This 734 prevents them from going anywhere except their intended 735 destination. This catches hard-to-find kernel bugs and 736 mis-behaving drivers and devices that do not use the DMA-API 737 properly to set up their DMA buffers. The IOMMU can be 738 turned off at boot time with the iommu=off parameter. 739 Normally the kernel will make the right choice by itself. 740 If unsure, say Y. 741 742config CALGARY_IOMMU_ENABLED_BY_DEFAULT 743 def_bool y 744 prompt "Should Calgary be enabled by default?" 745 depends on CALGARY_IOMMU 746 ---help--- 747 Should Calgary be enabled by default? if you choose 'y', Calgary 748 will be used (if it exists). If you choose 'n', Calgary will not be 749 used even if it exists. If you choose 'n' and would like to use 750 Calgary anyway, pass 'iommu=calgary' on the kernel command line. 751 If unsure, say Y. 752 753# need this always selected by IOMMU for the VIA workaround 754config SWIOTLB 755 def_bool y if X86_64 756 ---help--- 757 Support for software bounce buffers used on x86-64 systems 758 which don't have a hardware IOMMU (e.g. the current generation 759 of Intel's x86-64 CPUs). Using this PCI devices which can only 760 access 32-bits of memory can be used on systems with more than 761 3 GB of memory. If unsure, say Y. 762 763config IOMMU_HELPER 764 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU) 765 766config MAXSMP 767 bool "Enable Maximum number of SMP Processors and NUMA Nodes" 768 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL 769 select CPUMASK_OFFSTACK 770 ---help--- 771 Enable maximum number of CPUS and NUMA Nodes for this architecture. 772 If unsure, say N. 773 774config NR_CPUS 775 int "Maximum number of CPUs" if SMP && !MAXSMP 776 range 2 8 if SMP && X86_32 && !X86_BIGSMP 777 range 2 512 if SMP && !MAXSMP 778 default "1" if !SMP 779 default "4096" if MAXSMP 780 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000) 781 default "8" if SMP 782 ---help--- 783 This allows you to specify the maximum number of CPUs which this 784 kernel will support. The maximum supported value is 512 and the 785 minimum value which makes sense is 2. 786 787 This is purely to save memory - each supported CPU adds 788 approximately eight kilobytes to the kernel image. 789 790config SCHED_SMT 791 bool "SMT (Hyperthreading) scheduler support" 792 depends on X86_HT 793 ---help--- 794 SMT scheduler support improves the CPU scheduler's decision making 795 when dealing with Intel Pentium 4 chips with HyperThreading at a 796 cost of slightly increased overhead in some places. If unsure say 797 N here. 798 799config SCHED_MC 800 def_bool y 801 prompt "Multi-core scheduler support" 802 depends on X86_HT 803 ---help--- 804 Multi-core scheduler support improves the CPU scheduler's decision 805 making when dealing with multi-core CPU chips at a cost of slightly 806 increased overhead in some places. If unsure say N here. 807 808config IRQ_TIME_ACCOUNTING 809 bool "Fine granularity task level IRQ time accounting" 810 default n 811 ---help--- 812 Select this option to enable fine granularity task irq time 813 accounting. This is done by reading a timestamp on each 814 transitions between softirq and hardirq state, so there can be a 815 small performance impact. 816 817 If in doubt, say N here. 818 819source "kernel/Kconfig.preempt" 820 821config X86_UP_APIC 822 bool "Local APIC support on uniprocessors" 823 depends on X86_32 && !SMP && !X86_32_NON_STANDARD 824 ---help--- 825 A local APIC (Advanced Programmable Interrupt Controller) is an 826 integrated interrupt controller in the CPU. If you have a single-CPU 827 system which has a processor with a local APIC, you can say Y here to 828 enable and use it. If you say Y here even though your machine doesn't 829 have a local APIC, then the kernel will still run with no slowdown at 830 all. The local APIC supports CPU-generated self-interrupts (timer, 831 performance counters), and the NMI watchdog which detects hard 832 lockups. 833 834config X86_UP_IOAPIC 835 bool "IO-APIC support on uniprocessors" 836 depends on X86_UP_APIC 837 ---help--- 838 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 839 SMP-capable replacement for PC-style interrupt controllers. Most 840 SMP systems and many recent uniprocessor systems have one. 841 842 If you have a single-CPU system with an IO-APIC, you can say Y here 843 to use it. If you say Y here even though your machine doesn't have 844 an IO-APIC, then the kernel will still run with no slowdown at all. 845 846config X86_LOCAL_APIC 847 def_bool y 848 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC 849 850config X86_IO_APIC 851 def_bool y 852 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC 853 854config X86_VISWS_APIC 855 def_bool y 856 depends on X86_32 && X86_VISWS 857 858config X86_REROUTE_FOR_BROKEN_BOOT_IRQS 859 bool "Reroute for broken boot IRQs" 860 depends on X86_IO_APIC 861 ---help--- 862 This option enables a workaround that fixes a source of 863 spurious interrupts. This is recommended when threaded 864 interrupt handling is used on systems where the generation of 865 superfluous "boot interrupts" cannot be disabled. 866 867 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 868 entry in the chipset's IO-APIC is masked (as, e.g. the RT 869 kernel does during interrupt handling). On chipsets where this 870 boot IRQ generation cannot be disabled, this workaround keeps 871 the original IRQ line masked so that only the equivalent "boot 872 IRQ" is delivered to the CPUs. The workaround also tells the 873 kernel to set up the IRQ handler on the boot IRQ line. In this 874 way only one interrupt is delivered to the kernel. Otherwise 875 the spurious second interrupt may cause the kernel to bring 876 down (vital) interrupt lines. 877 878 Only affects "broken" chipsets. Interrupt sharing may be 879 increased on these systems. 880 881config X86_MCE 882 bool "Machine Check / overheating reporting" 883 ---help--- 884 Machine Check support allows the processor to notify the 885 kernel if it detects a problem (e.g. overheating, data corruption). 886 The action the kernel takes depends on the severity of the problem, 887 ranging from warning messages to halting the machine. 888 889config X86_MCE_INTEL 890 def_bool y 891 prompt "Intel MCE features" 892 depends on X86_MCE && X86_LOCAL_APIC 893 ---help--- 894 Additional support for intel specific MCE features such as 895 the thermal monitor. 896 897config X86_MCE_AMD 898 def_bool y 899 prompt "AMD MCE features" 900 depends on X86_MCE && X86_LOCAL_APIC 901 ---help--- 902 Additional support for AMD specific MCE features such as 903 the DRAM Error Threshold. 904 905config X86_ANCIENT_MCE 906 bool "Support for old Pentium 5 / WinChip machine checks" 907 depends on X86_32 && X86_MCE 908 ---help--- 909 Include support for machine check handling on old Pentium 5 or WinChip 910 systems. These typically need to be enabled explicitely on the command 911 line. 912 913config X86_MCE_THRESHOLD 914 depends on X86_MCE_AMD || X86_MCE_INTEL 915 def_bool y 916 917config X86_MCE_INJECT 918 depends on X86_MCE 919 tristate "Machine check injector support" 920 ---help--- 921 Provide support for injecting machine checks for testing purposes. 922 If you don't know what a machine check is and you don't do kernel 923 QA it is safe to say n. 924 925config X86_THERMAL_VECTOR 926 def_bool y 927 depends on X86_MCE_INTEL 928 929config VM86 930 bool "Enable VM86 support" if EXPERT 931 default y 932 depends on X86_32 933 ---help--- 934 This option is required by programs like DOSEMU to run 16-bit legacy 935 code on X86 processors. It also may be needed by software like 936 XFree86 to initialize some video cards via BIOS. Disabling this 937 option saves about 6k. 938 939config TOSHIBA 940 tristate "Toshiba Laptop support" 941 depends on X86_32 942 ---help--- 943 This adds a driver to safely access the System Management Mode of 944 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 945 not work on models with a Phoenix BIOS. The System Management Mode 946 is used to set the BIOS and power saving options on Toshiba portables. 947 948 For information on utilities to make use of this driver see the 949 Toshiba Linux utilities web site at: 950 <http://www.buzzard.org.uk/toshiba/>. 951 952 Say Y if you intend to run this kernel on a Toshiba portable. 953 Say N otherwise. 954 955config I8K 956 tristate "Dell laptop support" 957 select HWMON 958 ---help--- 959 This adds a driver to safely access the System Management Mode 960 of the CPU on the Dell Inspiron 8000. The System Management Mode 961 is used to read cpu temperature and cooling fan status and to 962 control the fans on the I8K portables. 963 964 This driver has been tested only on the Inspiron 8000 but it may 965 also work with other Dell laptops. You can force loading on other 966 models by passing the parameter `force=1' to the module. Use at 967 your own risk. 968 969 For information on utilities to make use of this driver see the 970 I8K Linux utilities web site at: 971 <http://people.debian.org/~dz/i8k/> 972 973 Say Y if you intend to run this kernel on a Dell Inspiron 8000. 974 Say N otherwise. 975 976config X86_REBOOTFIXUPS 977 bool "Enable X86 board specific fixups for reboot" 978 depends on X86_32 979 ---help--- 980 This enables chipset and/or board specific fixups to be done 981 in order to get reboot to work correctly. This is only needed on 982 some combinations of hardware and BIOS. The symptom, for which 983 this config is intended, is when reboot ends with a stalled/hung 984 system. 985 986 Currently, the only fixup is for the Geode machines using 987 CS5530A and CS5536 chipsets and the RDC R-321x SoC. 988 989 Say Y if you want to enable the fixup. Currently, it's safe to 990 enable this option even if you don't need it. 991 Say N otherwise. 992 993config MICROCODE 994 tristate "/dev/cpu/microcode - microcode support" 995 select FW_LOADER 996 ---help--- 997 If you say Y here, you will be able to update the microcode on 998 certain Intel and AMD processors. The Intel support is for the 999 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, 1000 Pentium 4, Xeon etc. The AMD support is for family 0x10 and 1001 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra. 1002 You will obviously need the actual microcode binary data itself 1003 which is not shipped with the Linux kernel. 1004 1005 This option selects the general module only, you need to select 1006 at least one vendor specific module as well. 1007 1008 To compile this driver as a module, choose M here: the 1009 module will be called microcode. 1010 1011config MICROCODE_INTEL 1012 bool "Intel microcode patch loading support" 1013 depends on MICROCODE 1014 default MICROCODE 1015 select FW_LOADER 1016 ---help--- 1017 This options enables microcode patch loading support for Intel 1018 processors. 1019 1020 For latest news and information on obtaining all the required 1021 Intel ingredients for this driver, check: 1022 <http://www.urbanmyth.org/microcode/>. 1023 1024config MICROCODE_AMD 1025 bool "AMD microcode patch loading support" 1026 depends on MICROCODE 1027 select FW_LOADER 1028 ---help--- 1029 If you select this option, microcode patch loading support for AMD 1030 processors will be enabled. 1031 1032config MICROCODE_OLD_INTERFACE 1033 def_bool y 1034 depends on MICROCODE 1035 1036config X86_MSR 1037 tristate "/dev/cpu/*/msr - Model-specific register support" 1038 ---help--- 1039 This device gives privileged processes access to the x86 1040 Model-Specific Registers (MSRs). It is a character device with 1041 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1042 MSR accesses are directed to a specific CPU on multi-processor 1043 systems. 1044 1045config X86_CPUID 1046 tristate "/dev/cpu/*/cpuid - CPU information support" 1047 ---help--- 1048 This device gives processes access to the x86 CPUID instruction to 1049 be executed on a specific processor. It is a character device 1050 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1051 /dev/cpu/31/cpuid. 1052 1053choice 1054 prompt "High Memory Support" 1055 default HIGHMEM64G if X86_NUMAQ 1056 default HIGHMEM4G 1057 depends on X86_32 1058 1059config NOHIGHMEM 1060 bool "off" 1061 depends on !X86_NUMAQ 1062 ---help--- 1063 Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1064 However, the address space of 32-bit x86 processors is only 4 1065 Gigabytes large. That means that, if you have a large amount of 1066 physical memory, not all of it can be "permanently mapped" by the 1067 kernel. The physical memory that's not permanently mapped is called 1068 "high memory". 1069 1070 If you are compiling a kernel which will never run on a machine with 1071 more than 1 Gigabyte total physical RAM, answer "off" here (default 1072 choice and suitable for most users). This will result in a "3GB/1GB" 1073 split: 3GB are mapped so that each process sees a 3GB virtual memory 1074 space and the remaining part of the 4GB virtual memory space is used 1075 by the kernel to permanently map as much physical memory as 1076 possible. 1077 1078 If the machine has between 1 and 4 Gigabytes physical RAM, then 1079 answer "4GB" here. 1080 1081 If more than 4 Gigabytes is used then answer "64GB" here. This 1082 selection turns Intel PAE (Physical Address Extension) mode on. 1083 PAE implements 3-level paging on IA32 processors. PAE is fully 1084 supported by Linux, PAE mode is implemented on all recent Intel 1085 processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1086 then the kernel will not boot on CPUs that don't support PAE! 1087 1088 The actual amount of total physical memory will either be 1089 auto detected or can be forced by using a kernel command line option 1090 such as "mem=256M". (Try "man bootparam" or see the documentation of 1091 your boot loader (lilo or loadlin) about how to pass options to the 1092 kernel at boot time.) 1093 1094 If unsure, say "off". 1095 1096config HIGHMEM4G 1097 bool "4GB" 1098 depends on !X86_NUMAQ 1099 ---help--- 1100 Select this if you have a 32-bit processor and between 1 and 4 1101 gigabytes of physical RAM. 1102 1103config HIGHMEM64G 1104 bool "64GB" 1105 depends on !M386 && !M486 1106 select X86_PAE 1107 ---help--- 1108 Select this if you have a 32-bit processor and more than 4 1109 gigabytes of physical RAM. 1110 1111endchoice 1112 1113choice 1114 depends on EXPERIMENTAL 1115 prompt "Memory split" if EXPERT 1116 default VMSPLIT_3G 1117 depends on X86_32 1118 ---help--- 1119 Select the desired split between kernel and user memory. 1120 1121 If the address range available to the kernel is less than the 1122 physical memory installed, the remaining memory will be available 1123 as "high memory". Accessing high memory is a little more costly 1124 than low memory, as it needs to be mapped into the kernel first. 1125 Note that increasing the kernel address space limits the range 1126 available to user programs, making the address space there 1127 tighter. Selecting anything other than the default 3G/1G split 1128 will also likely make your kernel incompatible with binary-only 1129 kernel modules. 1130 1131 If you are not absolutely sure what you are doing, leave this 1132 option alone! 1133 1134 config VMSPLIT_3G 1135 bool "3G/1G user/kernel split" 1136 config VMSPLIT_3G_OPT 1137 depends on !X86_PAE 1138 bool "3G/1G user/kernel split (for full 1G low memory)" 1139 config VMSPLIT_2G 1140 bool "2G/2G user/kernel split" 1141 config VMSPLIT_2G_OPT 1142 depends on !X86_PAE 1143 bool "2G/2G user/kernel split (for full 2G low memory)" 1144 config VMSPLIT_1G 1145 bool "1G/3G user/kernel split" 1146endchoice 1147 1148config PAGE_OFFSET 1149 hex 1150 default 0xB0000000 if VMSPLIT_3G_OPT 1151 default 0x80000000 if VMSPLIT_2G 1152 default 0x78000000 if VMSPLIT_2G_OPT 1153 default 0x40000000 if VMSPLIT_1G 1154 default 0xC0000000 1155 depends on X86_32 1156 1157config HIGHMEM 1158 def_bool y 1159 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1160 1161config X86_PAE 1162 bool "PAE (Physical Address Extension) Support" 1163 depends on X86_32 && !HIGHMEM4G 1164 ---help--- 1165 PAE is required for NX support, and furthermore enables 1166 larger swapspace support for non-overcommit purposes. It 1167 has the cost of more pagetable lookup overhead, and also 1168 consumes more pagetable space per process. 1169 1170config ARCH_PHYS_ADDR_T_64BIT 1171 def_bool X86_64 || X86_PAE 1172 1173config ARCH_DMA_ADDR_T_64BIT 1174 def_bool X86_64 || HIGHMEM64G 1175 1176config DIRECT_GBPAGES 1177 bool "Enable 1GB pages for kernel pagetables" if EXPERT 1178 default y 1179 depends on X86_64 1180 ---help--- 1181 Allow the kernel linear mapping to use 1GB pages on CPUs that 1182 support it. This can improve the kernel's performance a tiny bit by 1183 reducing TLB pressure. If in doubt, say "Y". 1184 1185# Common NUMA Features 1186config NUMA 1187 bool "Numa Memory Allocation and Scheduler Support" 1188 depends on SMP 1189 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL) 1190 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP) 1191 ---help--- 1192 Enable NUMA (Non Uniform Memory Access) support. 1193 1194 The kernel will try to allocate memory used by a CPU on the 1195 local memory controller of the CPU and add some more 1196 NUMA awareness to the kernel. 1197 1198 For 64-bit this is recommended if the system is Intel Core i7 1199 (or later), AMD Opteron, or EM64T NUMA. 1200 1201 For 32-bit this is only needed on (rare) 32-bit-only platforms 1202 that support NUMA topologies, such as NUMAQ / Summit, or if you 1203 boot a 32-bit kernel on a 64-bit NUMA platform. 1204 1205 Otherwise, you should say N. 1206 1207comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI" 1208 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI) 1209 1210config AMD_NUMA 1211 def_bool y 1212 prompt "Old style AMD Opteron NUMA detection" 1213 depends on X86_64 && NUMA && PCI 1214 ---help--- 1215 Enable AMD NUMA node topology detection. You should say Y here if 1216 you have a multi processor AMD system. This uses an old method to 1217 read the NUMA configuration directly from the builtin Northbridge 1218 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1219 which also takes priority if both are compiled in. 1220 1221config X86_64_ACPI_NUMA 1222 def_bool y 1223 prompt "ACPI NUMA detection" 1224 depends on X86_64 && NUMA && ACPI && PCI 1225 select ACPI_NUMA 1226 ---help--- 1227 Enable ACPI SRAT based node topology detection. 1228 1229# Some NUMA nodes have memory ranges that span 1230# other nodes. Even though a pfn is valid and 1231# between a node's start and end pfns, it may not 1232# reside on that node. See memmap_init_zone() 1233# for details. 1234config NODES_SPAN_OTHER_NODES 1235 def_bool y 1236 depends on X86_64_ACPI_NUMA 1237 1238config NUMA_EMU 1239 bool "NUMA emulation" 1240 depends on NUMA 1241 ---help--- 1242 Enable NUMA emulation. A flat machine will be split 1243 into virtual nodes when booted with "numa=fake=N", where N is the 1244 number of nodes. This is only useful for debugging. 1245 1246config NODES_SHIFT 1247 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 1248 range 1 10 1249 default "10" if MAXSMP 1250 default "6" if X86_64 1251 default "4" if X86_NUMAQ 1252 default "3" 1253 depends on NEED_MULTIPLE_NODES 1254 ---help--- 1255 Specify the maximum number of NUMA Nodes available on the target 1256 system. Increases memory reserved to accommodate various tables. 1257 1258config HAVE_ARCH_BOOTMEM 1259 def_bool y 1260 depends on X86_32 && NUMA 1261 1262config HAVE_ARCH_ALLOC_REMAP 1263 def_bool y 1264 depends on X86_32 && NUMA 1265 1266config ARCH_HAVE_MEMORY_PRESENT 1267 def_bool y 1268 depends on X86_32 && DISCONTIGMEM 1269 1270config NEED_NODE_MEMMAP_SIZE 1271 def_bool y 1272 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1273 1274config ARCH_FLATMEM_ENABLE 1275 def_bool y 1276 depends on X86_32 && !NUMA 1277 1278config ARCH_DISCONTIGMEM_ENABLE 1279 def_bool y 1280 depends on NUMA && X86_32 1281 1282config ARCH_DISCONTIGMEM_DEFAULT 1283 def_bool y 1284 depends on NUMA && X86_32 1285 1286config ARCH_SPARSEMEM_ENABLE 1287 def_bool y 1288 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD 1289 select SPARSEMEM_STATIC if X86_32 1290 select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1291 1292config ARCH_SPARSEMEM_DEFAULT 1293 def_bool y 1294 depends on X86_64 1295 1296config ARCH_SELECT_MEMORY_MODEL 1297 def_bool y 1298 depends on ARCH_SPARSEMEM_ENABLE 1299 1300config ARCH_MEMORY_PROBE 1301 def_bool X86_64 1302 depends on MEMORY_HOTPLUG 1303 1304config ARCH_PROC_KCORE_TEXT 1305 def_bool y 1306 depends on X86_64 && PROC_KCORE 1307 1308config ILLEGAL_POINTER_VALUE 1309 hex 1310 default 0 if X86_32 1311 default 0xdead000000000000 if X86_64 1312 1313source "mm/Kconfig" 1314 1315config HIGHPTE 1316 bool "Allocate 3rd-level pagetables from highmem" 1317 depends on HIGHMEM 1318 ---help--- 1319 The VM uses one page table entry for each page of physical memory. 1320 For systems with a lot of RAM, this can be wasteful of precious 1321 low memory. Setting this option will put user-space page table 1322 entries in high memory. 1323 1324config X86_CHECK_BIOS_CORRUPTION 1325 bool "Check for low memory corruption" 1326 ---help--- 1327 Periodically check for memory corruption in low memory, which 1328 is suspected to be caused by BIOS. Even when enabled in the 1329 configuration, it is disabled at runtime. Enable it by 1330 setting "memory_corruption_check=1" on the kernel command 1331 line. By default it scans the low 64k of memory every 60 1332 seconds; see the memory_corruption_check_size and 1333 memory_corruption_check_period parameters in 1334 Documentation/kernel-parameters.txt to adjust this. 1335 1336 When enabled with the default parameters, this option has 1337 almost no overhead, as it reserves a relatively small amount 1338 of memory and scans it infrequently. It both detects corruption 1339 and prevents it from affecting the running system. 1340 1341 It is, however, intended as a diagnostic tool; if repeatable 1342 BIOS-originated corruption always affects the same memory, 1343 you can use memmap= to prevent the kernel from using that 1344 memory. 1345 1346config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1347 bool "Set the default setting of memory_corruption_check" 1348 depends on X86_CHECK_BIOS_CORRUPTION 1349 default y 1350 ---help--- 1351 Set whether the default state of memory_corruption_check is 1352 on or off. 1353 1354config X86_RESERVE_LOW 1355 int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1356 default 64 1357 range 4 640 1358 ---help--- 1359 Specify the amount of low memory to reserve for the BIOS. 1360 1361 The first page contains BIOS data structures that the kernel 1362 must not use, so that page must always be reserved. 1363 1364 By default we reserve the first 64K of physical RAM, as a 1365 number of BIOSes are known to corrupt that memory range 1366 during events such as suspend/resume or monitor cable 1367 insertion, so it must not be used by the kernel. 1368 1369 You can set this to 4 if you are absolutely sure that you 1370 trust the BIOS to get all its memory reservations and usages 1371 right. If you know your BIOS have problems beyond the 1372 default 64K area, you can set this to 640 to avoid using the 1373 entire low memory range. 1374 1375 If you have doubts about the BIOS (e.g. suspend/resume does 1376 not work or there's kernel crashes after certain hardware 1377 hotplug events) then you might want to enable 1378 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1379 typical corruption patterns. 1380 1381 Leave this to the default value of 64 if you are unsure. 1382 1383config MATH_EMULATION 1384 bool 1385 prompt "Math emulation" if X86_32 1386 ---help--- 1387 Linux can emulate a math coprocessor (used for floating point 1388 operations) if you don't have one. 486DX and Pentium processors have 1389 a math coprocessor built in, 486SX and 386 do not, unless you added 1390 a 487DX or 387, respectively. (The messages during boot time can 1391 give you some hints here ["man dmesg"].) Everyone needs either a 1392 coprocessor or this emulation. 1393 1394 If you don't have a math coprocessor, you need to say Y here; if you 1395 say Y here even though you have a coprocessor, the coprocessor will 1396 be used nevertheless. (This behavior can be changed with the kernel 1397 command line option "no387", which comes handy if your coprocessor 1398 is broken. Try "man bootparam" or see the documentation of your boot 1399 loader (lilo or loadlin) about how to pass options to the kernel at 1400 boot time.) This means that it is a good idea to say Y here if you 1401 intend to use this kernel on different machines. 1402 1403 More information about the internals of the Linux math coprocessor 1404 emulation can be found in <file:arch/x86/math-emu/README>. 1405 1406 If you are not sure, say Y; apart from resulting in a 66 KB bigger 1407 kernel, it won't hurt. 1408 1409config MTRR 1410 def_bool y 1411 prompt "MTRR (Memory Type Range Register) support" if EXPERT 1412 ---help--- 1413 On Intel P6 family processors (Pentium Pro, Pentium II and later) 1414 the Memory Type Range Registers (MTRRs) may be used to control 1415 processor access to memory ranges. This is most useful if you have 1416 a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1417 allows bus write transfers to be combined into a larger transfer 1418 before bursting over the PCI/AGP bus. This can increase performance 1419 of image write operations 2.5 times or more. Saying Y here creates a 1420 /proc/mtrr file which may be used to manipulate your processor's 1421 MTRRs. Typically the X server should use this. 1422 1423 This code has a reasonably generic interface so that similar 1424 control registers on other processors can be easily supported 1425 as well: 1426 1427 The Cyrix 6x86, 6x86MX and M II processors have Address Range 1428 Registers (ARRs) which provide a similar functionality to MTRRs. For 1429 these, the ARRs are used to emulate the MTRRs. 1430 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1431 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1432 write-combining. All of these processors are supported by this code 1433 and it makes sense to say Y here if you have one of them. 1434 1435 Saying Y here also fixes a problem with buggy SMP BIOSes which only 1436 set the MTRRs for the boot CPU and not for the secondary CPUs. This 1437 can lead to all sorts of problems, so it's good to say Y here. 1438 1439 You can safely say Y even if your machine doesn't have MTRRs, you'll 1440 just add about 9 KB to your kernel. 1441 1442 See <file:Documentation/x86/mtrr.txt> for more information. 1443 1444config MTRR_SANITIZER 1445 def_bool y 1446 prompt "MTRR cleanup support" 1447 depends on MTRR 1448 ---help--- 1449 Convert MTRR layout from continuous to discrete, so X drivers can 1450 add writeback entries. 1451 1452 Can be disabled with disable_mtrr_cleanup on the kernel command line. 1453 The largest mtrr entry size for a continuous block can be set with 1454 mtrr_chunk_size. 1455 1456 If unsure, say Y. 1457 1458config MTRR_SANITIZER_ENABLE_DEFAULT 1459 int "MTRR cleanup enable value (0-1)" 1460 range 0 1 1461 default "0" 1462 depends on MTRR_SANITIZER 1463 ---help--- 1464 Enable mtrr cleanup default value 1465 1466config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 1467 int "MTRR cleanup spare reg num (0-7)" 1468 range 0 7 1469 default "1" 1470 depends on MTRR_SANITIZER 1471 ---help--- 1472 mtrr cleanup spare entries default, it can be changed via 1473 mtrr_spare_reg_nr=N on the kernel command line. 1474 1475config X86_PAT 1476 def_bool y 1477 prompt "x86 PAT support" if EXPERT 1478 depends on MTRR 1479 ---help--- 1480 Use PAT attributes to setup page level cache control. 1481 1482 PATs are the modern equivalents of MTRRs and are much more 1483 flexible than MTRRs. 1484 1485 Say N here if you see bootup problems (boot crash, boot hang, 1486 spontaneous reboots) or a non-working video driver. 1487 1488 If unsure, say Y. 1489 1490config ARCH_USES_PG_UNCACHED 1491 def_bool y 1492 depends on X86_PAT 1493 1494config ARCH_RANDOM 1495 def_bool y 1496 prompt "x86 architectural random number generator" if EXPERT 1497 ---help--- 1498 Enable the x86 architectural RDRAND instruction 1499 (Intel Bull Mountain technology) to generate random numbers. 1500 If supported, this is a high bandwidth, cryptographically 1501 secure hardware random number generator. 1502 1503config EFI 1504 bool "EFI runtime service support" 1505 depends on ACPI 1506 ---help--- 1507 This enables the kernel to use EFI runtime services that are 1508 available (such as the EFI variable services). 1509 1510 This option is only useful on systems that have EFI firmware. 1511 In addition, you should use the latest ELILO loader available 1512 at <http://elilo.sourceforge.net> in order to take advantage 1513 of EFI runtime services. However, even with this option, the 1514 resultant kernel should continue to boot on existing non-EFI 1515 platforms. 1516 1517config EFI_STUB 1518 bool "EFI stub support" 1519 depends on EFI 1520 ---help--- 1521 This kernel feature allows a bzImage to be loaded directly 1522 by EFI firmware without the use of a bootloader. 1523 1524config SECCOMP 1525 def_bool y 1526 prompt "Enable seccomp to safely compute untrusted bytecode" 1527 ---help--- 1528 This kernel feature is useful for number crunching applications 1529 that may need to compute untrusted bytecode during their 1530 execution. By using pipes or other transports made available to 1531 the process as file descriptors supporting the read/write 1532 syscalls, it's possible to isolate those applications in 1533 their own address space using seccomp. Once seccomp is 1534 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1535 and the task is only allowed to execute a few safe syscalls 1536 defined by each seccomp mode. 1537 1538 If unsure, say Y. Only embedded should say N here. 1539 1540config CC_STACKPROTECTOR 1541 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)" 1542 ---help--- 1543 This option turns on the -fstack-protector GCC feature. This 1544 feature puts, at the beginning of functions, a canary value on 1545 the stack just before the return address, and validates 1546 the value just before actually returning. Stack based buffer 1547 overflows (that need to overwrite this return address) now also 1548 overwrite the canary, which gets detected and the attack is then 1549 neutralized via a kernel panic. 1550 1551 This feature requires gcc version 4.2 or above, or a distribution 1552 gcc with the feature backported. Older versions are automatically 1553 detected and for those versions, this configuration option is 1554 ignored. (and a warning is printed during bootup) 1555 1556source kernel/Kconfig.hz 1557 1558config KEXEC 1559 bool "kexec system call" 1560 ---help--- 1561 kexec is a system call that implements the ability to shutdown your 1562 current kernel, and to start another kernel. It is like a reboot 1563 but it is independent of the system firmware. And like a reboot 1564 you can start any kernel with it, not just Linux. 1565 1566 The name comes from the similarity to the exec system call. 1567 1568 It is an ongoing process to be certain the hardware in a machine 1569 is properly shutdown, so do not be surprised if this code does not 1570 initially work for you. It may help to enable device hotplugging 1571 support. As of this writing the exact hardware interface is 1572 strongly in flux, so no good recommendation can be made. 1573 1574config CRASH_DUMP 1575 bool "kernel crash dumps" 1576 depends on X86_64 || (X86_32 && HIGHMEM) 1577 ---help--- 1578 Generate crash dump after being started by kexec. 1579 This should be normally only set in special crash dump kernels 1580 which are loaded in the main kernel with kexec-tools into 1581 a specially reserved region and then later executed after 1582 a crash by kdump/kexec. The crash dump kernel must be compiled 1583 to a memory address not used by the main kernel or BIOS using 1584 PHYSICAL_START, or it must be built as a relocatable image 1585 (CONFIG_RELOCATABLE=y). 1586 For more details see Documentation/kdump/kdump.txt 1587 1588config KEXEC_JUMP 1589 bool "kexec jump (EXPERIMENTAL)" 1590 depends on EXPERIMENTAL 1591 depends on KEXEC && HIBERNATION 1592 ---help--- 1593 Jump between original kernel and kexeced kernel and invoke 1594 code in physical address mode via KEXEC 1595 1596config PHYSICAL_START 1597 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1598 default "0x1000000" 1599 ---help--- 1600 This gives the physical address where the kernel is loaded. 1601 1602 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1603 bzImage will decompress itself to above physical address and 1604 run from there. Otherwise, bzImage will run from the address where 1605 it has been loaded by the boot loader and will ignore above physical 1606 address. 1607 1608 In normal kdump cases one does not have to set/change this option 1609 as now bzImage can be compiled as a completely relocatable image 1610 (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1611 address. This option is mainly useful for the folks who don't want 1612 to use a bzImage for capturing the crash dump and want to use a 1613 vmlinux instead. vmlinux is not relocatable hence a kernel needs 1614 to be specifically compiled to run from a specific memory area 1615 (normally a reserved region) and this option comes handy. 1616 1617 So if you are using bzImage for capturing the crash dump, 1618 leave the value here unchanged to 0x1000000 and set 1619 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1620 for capturing the crash dump change this value to start of 1621 the reserved region. In other words, it can be set based on 1622 the "X" value as specified in the "crashkernel=YM@XM" 1623 command line boot parameter passed to the panic-ed 1624 kernel. Please take a look at Documentation/kdump/kdump.txt 1625 for more details about crash dumps. 1626 1627 Usage of bzImage for capturing the crash dump is recommended as 1628 one does not have to build two kernels. Same kernel can be used 1629 as production kernel and capture kernel. Above option should have 1630 gone away after relocatable bzImage support is introduced. But it 1631 is present because there are users out there who continue to use 1632 vmlinux for dump capture. This option should go away down the 1633 line. 1634 1635 Don't change this unless you know what you are doing. 1636 1637config RELOCATABLE 1638 bool "Build a relocatable kernel" 1639 default y 1640 ---help--- 1641 This builds a kernel image that retains relocation information 1642 so it can be loaded someplace besides the default 1MB. 1643 The relocations tend to make the kernel binary about 10% larger, 1644 but are discarded at runtime. 1645 1646 One use is for the kexec on panic case where the recovery kernel 1647 must live at a different physical address than the primary 1648 kernel. 1649 1650 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1651 it has been loaded at and the compile time physical address 1652 (CONFIG_PHYSICAL_START) is ignored. 1653 1654# Relocation on x86-32 needs some additional build support 1655config X86_NEED_RELOCS 1656 def_bool y 1657 depends on X86_32 && RELOCATABLE 1658 1659config PHYSICAL_ALIGN 1660 hex "Alignment value to which kernel should be aligned" if X86_32 1661 default "0x1000000" 1662 range 0x2000 0x1000000 1663 ---help--- 1664 This value puts the alignment restrictions on physical address 1665 where kernel is loaded and run from. Kernel is compiled for an 1666 address which meets above alignment restriction. 1667 1668 If bootloader loads the kernel at a non-aligned address and 1669 CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1670 address aligned to above value and run from there. 1671 1672 If bootloader loads the kernel at a non-aligned address and 1673 CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1674 load address and decompress itself to the address it has been 1675 compiled for and run from there. The address for which kernel is 1676 compiled already meets above alignment restrictions. Hence the 1677 end result is that kernel runs from a physical address meeting 1678 above alignment restrictions. 1679 1680 Don't change this unless you know what you are doing. 1681 1682config HOTPLUG_CPU 1683 bool "Support for hot-pluggable CPUs" 1684 depends on SMP && HOTPLUG 1685 ---help--- 1686 Say Y here to allow turning CPUs off and on. CPUs can be 1687 controlled through /sys/devices/system/cpu. 1688 ( Note: power management support will enable this option 1689 automatically on SMP systems. ) 1690 Say N if you want to disable CPU hotplug. 1691 1692config COMPAT_VDSO 1693 def_bool y 1694 prompt "Compat VDSO support" 1695 depends on X86_32 || IA32_EMULATION 1696 ---help--- 1697 Map the 32-bit VDSO to the predictable old-style address too. 1698 1699 Say N here if you are running a sufficiently recent glibc 1700 version (2.3.3 or later), to remove the high-mapped 1701 VDSO mapping and to exclusively use the randomized VDSO. 1702 1703 If unsure, say Y. 1704 1705config CMDLINE_BOOL 1706 bool "Built-in kernel command line" 1707 ---help--- 1708 Allow for specifying boot arguments to the kernel at 1709 build time. On some systems (e.g. embedded ones), it is 1710 necessary or convenient to provide some or all of the 1711 kernel boot arguments with the kernel itself (that is, 1712 to not rely on the boot loader to provide them.) 1713 1714 To compile command line arguments into the kernel, 1715 set this option to 'Y', then fill in the 1716 the boot arguments in CONFIG_CMDLINE. 1717 1718 Systems with fully functional boot loaders (i.e. non-embedded) 1719 should leave this option set to 'N'. 1720 1721config CMDLINE 1722 string "Built-in kernel command string" 1723 depends on CMDLINE_BOOL 1724 default "" 1725 ---help--- 1726 Enter arguments here that should be compiled into the kernel 1727 image and used at boot time. If the boot loader provides a 1728 command line at boot time, it is appended to this string to 1729 form the full kernel command line, when the system boots. 1730 1731 However, you can use the CONFIG_CMDLINE_OVERRIDE option to 1732 change this behavior. 1733 1734 In most cases, the command line (whether built-in or provided 1735 by the boot loader) should specify the device for the root 1736 file system. 1737 1738config CMDLINE_OVERRIDE 1739 bool "Built-in command line overrides boot loader arguments" 1740 depends on CMDLINE_BOOL 1741 ---help--- 1742 Set this option to 'Y' to have the kernel ignore the boot loader 1743 command line, and use ONLY the built-in command line. 1744 1745 This is used to work around broken boot loaders. This should 1746 be set to 'N' under normal conditions. 1747 1748endmenu 1749 1750config ARCH_ENABLE_MEMORY_HOTPLUG 1751 def_bool y 1752 depends on X86_64 || (X86_32 && HIGHMEM) 1753 1754config ARCH_ENABLE_MEMORY_HOTREMOVE 1755 def_bool y 1756 depends on MEMORY_HOTPLUG 1757 1758config USE_PERCPU_NUMA_NODE_ID 1759 def_bool y 1760 depends on NUMA 1761 1762menu "Power management and ACPI options" 1763 1764config ARCH_HIBERNATION_HEADER 1765 def_bool y 1766 depends on X86_64 && HIBERNATION 1767 1768source "kernel/power/Kconfig" 1769 1770source "drivers/acpi/Kconfig" 1771 1772source "drivers/sfi/Kconfig" 1773 1774config X86_APM_BOOT 1775 def_bool y 1776 depends on APM 1777 1778menuconfig APM 1779 tristate "APM (Advanced Power Management) BIOS support" 1780 depends on X86_32 && PM_SLEEP 1781 ---help--- 1782 APM is a BIOS specification for saving power using several different 1783 techniques. This is mostly useful for battery powered laptops with 1784 APM compliant BIOSes. If you say Y here, the system time will be 1785 reset after a RESUME operation, the /proc/apm device will provide 1786 battery status information, and user-space programs will receive 1787 notification of APM "events" (e.g. battery status change). 1788 1789 If you select "Y" here, you can disable actual use of the APM 1790 BIOS by passing the "apm=off" option to the kernel at boot time. 1791 1792 Note that the APM support is almost completely disabled for 1793 machines with more than one CPU. 1794 1795 In order to use APM, you will need supporting software. For location 1796 and more information, read <file:Documentation/power/apm-acpi.txt> 1797 and the Battery Powered Linux mini-HOWTO, available from 1798 <http://www.tldp.org/docs.html#howto>. 1799 1800 This driver does not spin down disk drives (see the hdparm(8) 1801 manpage ("man 8 hdparm") for that), and it doesn't turn off 1802 VESA-compliant "green" monitors. 1803 1804 This driver does not support the TI 4000M TravelMate and the ACER 1805 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1806 desktop machines also don't have compliant BIOSes, and this driver 1807 may cause those machines to panic during the boot phase. 1808 1809 Generally, if you don't have a battery in your machine, there isn't 1810 much point in using this driver and you should say N. If you get 1811 random kernel OOPSes or reboots that don't seem to be related to 1812 anything, try disabling/enabling this option (or disabling/enabling 1813 APM in your BIOS). 1814 1815 Some other things you should try when experiencing seemingly random, 1816 "weird" problems: 1817 1818 1) make sure that you have enough swap space and that it is 1819 enabled. 1820 2) pass the "no-hlt" option to the kernel 1821 3) switch on floating point emulation in the kernel and pass 1822 the "no387" option to the kernel 1823 4) pass the "floppy=nodma" option to the kernel 1824 5) pass the "mem=4M" option to the kernel (thereby disabling 1825 all but the first 4 MB of RAM) 1826 6) make sure that the CPU is not over clocked. 1827 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1828 8) disable the cache from your BIOS settings 1829 9) install a fan for the video card or exchange video RAM 1830 10) install a better fan for the CPU 1831 11) exchange RAM chips 1832 12) exchange the motherboard. 1833 1834 To compile this driver as a module, choose M here: the 1835 module will be called apm. 1836 1837if APM 1838 1839config APM_IGNORE_USER_SUSPEND 1840 bool "Ignore USER SUSPEND" 1841 ---help--- 1842 This option will ignore USER SUSPEND requests. On machines with a 1843 compliant APM BIOS, you want to say N. However, on the NEC Versa M 1844 series notebooks, it is necessary to say Y because of a BIOS bug. 1845 1846config APM_DO_ENABLE 1847 bool "Enable PM at boot time" 1848 ---help--- 1849 Enable APM features at boot time. From page 36 of the APM BIOS 1850 specification: "When disabled, the APM BIOS does not automatically 1851 power manage devices, enter the Standby State, enter the Suspend 1852 State, or take power saving steps in response to CPU Idle calls." 1853 This driver will make CPU Idle calls when Linux is idle (unless this 1854 feature is turned off -- see "Do CPU IDLE calls", below). This 1855 should always save battery power, but more complicated APM features 1856 will be dependent on your BIOS implementation. You may need to turn 1857 this option off if your computer hangs at boot time when using APM 1858 support, or if it beeps continuously instead of suspending. Turn 1859 this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1860 T400CDT. This is off by default since most machines do fine without 1861 this feature. 1862 1863config APM_CPU_IDLE 1864 bool "Make CPU Idle calls when idle" 1865 ---help--- 1866 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 1867 On some machines, this can activate improved power savings, such as 1868 a slowed CPU clock rate, when the machine is idle. These idle calls 1869 are made after the idle loop has run for some length of time (e.g., 1870 333 mS). On some machines, this will cause a hang at boot time or 1871 whenever the CPU becomes idle. (On machines with more than one CPU, 1872 this option does nothing.) 1873 1874config APM_DISPLAY_BLANK 1875 bool "Enable console blanking using APM" 1876 ---help--- 1877 Enable console blanking using the APM. Some laptops can use this to 1878 turn off the LCD backlight when the screen blanker of the Linux 1879 virtual console blanks the screen. Note that this is only used by 1880 the virtual console screen blanker, and won't turn off the backlight 1881 when using the X Window system. This also doesn't have anything to 1882 do with your VESA-compliant power-saving monitor. Further, this 1883 option doesn't work for all laptops -- it might not turn off your 1884 backlight at all, or it might print a lot of errors to the console, 1885 especially if you are using gpm. 1886 1887config APM_ALLOW_INTS 1888 bool "Allow interrupts during APM BIOS calls" 1889 ---help--- 1890 Normally we disable external interrupts while we are making calls to 1891 the APM BIOS as a measure to lessen the effects of a badly behaving 1892 BIOS implementation. The BIOS should reenable interrupts if it 1893 needs to. Unfortunately, some BIOSes do not -- especially those in 1894 many of the newer IBM Thinkpads. If you experience hangs when you 1895 suspend, try setting this to Y. Otherwise, say N. 1896 1897endif # APM 1898 1899source "drivers/cpufreq/Kconfig" 1900 1901source "drivers/cpuidle/Kconfig" 1902 1903source "drivers/idle/Kconfig" 1904 1905endmenu 1906 1907 1908menu "Bus options (PCI etc.)" 1909 1910config PCI 1911 bool "PCI support" 1912 default y 1913 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC) 1914 ---help--- 1915 Find out whether you have a PCI motherboard. PCI is the name of a 1916 bus system, i.e. the way the CPU talks to the other stuff inside 1917 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 1918 VESA. If you have PCI, say Y, otherwise N. 1919 1920choice 1921 prompt "PCI access mode" 1922 depends on X86_32 && PCI 1923 default PCI_GOANY 1924 ---help--- 1925 On PCI systems, the BIOS can be used to detect the PCI devices and 1926 determine their configuration. However, some old PCI motherboards 1927 have BIOS bugs and may crash if this is done. Also, some embedded 1928 PCI-based systems don't have any BIOS at all. Linux can also try to 1929 detect the PCI hardware directly without using the BIOS. 1930 1931 With this option, you can specify how Linux should detect the 1932 PCI devices. If you choose "BIOS", the BIOS will be used, 1933 if you choose "Direct", the BIOS won't be used, and if you 1934 choose "MMConfig", then PCI Express MMCONFIG will be used. 1935 If you choose "Any", the kernel will try MMCONFIG, then the 1936 direct access method and falls back to the BIOS if that doesn't 1937 work. If unsure, go with the default, which is "Any". 1938 1939config PCI_GOBIOS 1940 bool "BIOS" 1941 1942config PCI_GOMMCONFIG 1943 bool "MMConfig" 1944 1945config PCI_GODIRECT 1946 bool "Direct" 1947 1948config PCI_GOOLPC 1949 bool "OLPC XO-1" 1950 depends on OLPC 1951 1952config PCI_GOANY 1953 bool "Any" 1954 1955endchoice 1956 1957config PCI_BIOS 1958 def_bool y 1959 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 1960 1961# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 1962config PCI_DIRECT 1963 def_bool y 1964 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 1965 1966config PCI_MMCONFIG 1967 def_bool y 1968 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 1969 1970config PCI_OLPC 1971 def_bool y 1972 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 1973 1974config PCI_XEN 1975 def_bool y 1976 depends on PCI && XEN 1977 select SWIOTLB_XEN 1978 1979config PCI_DOMAINS 1980 def_bool y 1981 depends on PCI 1982 1983config PCI_MMCONFIG 1984 bool "Support mmconfig PCI config space access" 1985 depends on X86_64 && PCI && ACPI 1986 1987config PCI_CNB20LE_QUIRK 1988 bool "Read CNB20LE Host Bridge Windows" if EXPERT 1989 default n 1990 depends on PCI && EXPERIMENTAL 1991 help 1992 Read the PCI windows out of the CNB20LE host bridge. This allows 1993 PCI hotplug to work on systems with the CNB20LE chipset which do 1994 not have ACPI. 1995 1996 There's no public spec for this chipset, and this functionality 1997 is known to be incomplete. 1998 1999 You should say N unless you know you need this. 2000 2001source "drivers/pci/pcie/Kconfig" 2002 2003source "drivers/pci/Kconfig" 2004 2005# x86_64 have no ISA slots, but can have ISA-style DMA. 2006config ISA_DMA_API 2007 bool "ISA-style DMA support" if (X86_64 && EXPERT) 2008 default y 2009 help 2010 Enables ISA-style DMA support for devices requiring such controllers. 2011 If unsure, say Y. 2012 2013if X86_32 2014 2015config ISA 2016 bool "ISA support" 2017 ---help--- 2018 Find out whether you have ISA slots on your motherboard. ISA is the 2019 name of a bus system, i.e. the way the CPU talks to the other stuff 2020 inside your box. Other bus systems are PCI, EISA, MicroChannel 2021 (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2022 newer boards don't support it. If you have ISA, say Y, otherwise N. 2023 2024config EISA 2025 bool "EISA support" 2026 depends on ISA 2027 ---help--- 2028 The Extended Industry Standard Architecture (EISA) bus was 2029 developed as an open alternative to the IBM MicroChannel bus. 2030 2031 The EISA bus provided some of the features of the IBM MicroChannel 2032 bus while maintaining backward compatibility with cards made for 2033 the older ISA bus. The EISA bus saw limited use between 1988 and 2034 1995 when it was made obsolete by the PCI bus. 2035 2036 Say Y here if you are building a kernel for an EISA-based machine. 2037 2038 Otherwise, say N. 2039 2040source "drivers/eisa/Kconfig" 2041 2042config MCA 2043 bool "MCA support" 2044 ---help--- 2045 MicroChannel Architecture is found in some IBM PS/2 machines and 2046 laptops. It is a bus system similar to PCI or ISA. See 2047 <file:Documentation/mca.txt> (and especially the web page given 2048 there) before attempting to build an MCA bus kernel. 2049 2050source "drivers/mca/Kconfig" 2051 2052config SCx200 2053 tristate "NatSemi SCx200 support" 2054 ---help--- 2055 This provides basic support for National Semiconductor's 2056 (now AMD's) Geode processors. The driver probes for the 2057 PCI-IDs of several on-chip devices, so its a good dependency 2058 for other scx200_* drivers. 2059 2060 If compiled as a module, the driver is named scx200. 2061 2062config SCx200HR_TIMER 2063 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2064 depends on SCx200 2065 default y 2066 ---help--- 2067 This driver provides a clocksource built upon the on-chip 2068 27MHz high-resolution timer. Its also a workaround for 2069 NSC Geode SC-1100's buggy TSC, which loses time when the 2070 processor goes idle (as is done by the scheduler). The 2071 other workaround is idle=poll boot option. 2072 2073config OLPC 2074 bool "One Laptop Per Child support" 2075 depends on !X86_PAE 2076 select GPIOLIB 2077 select OF 2078 select OF_PROMTREE 2079 ---help--- 2080 Add support for detecting the unique features of the OLPC 2081 XO hardware. 2082 2083config OLPC_XO1_PM 2084 bool "OLPC XO-1 Power Management" 2085 depends on OLPC && MFD_CS5535 && PM_SLEEP 2086 select MFD_CORE 2087 ---help--- 2088 Add support for poweroff and suspend of the OLPC XO-1 laptop. 2089 2090config OLPC_XO1_RTC 2091 bool "OLPC XO-1 Real Time Clock" 2092 depends on OLPC_XO1_PM && RTC_DRV_CMOS 2093 ---help--- 2094 Add support for the XO-1 real time clock, which can be used as a 2095 programmable wakeup source. 2096 2097config OLPC_XO1_SCI 2098 bool "OLPC XO-1 SCI extras" 2099 depends on OLPC && OLPC_XO1_PM 2100 select POWER_SUPPLY 2101 select GPIO_CS5535 2102 select MFD_CORE 2103 ---help--- 2104 Add support for SCI-based features of the OLPC XO-1 laptop: 2105 - EC-driven system wakeups 2106 - Power button 2107 - Ebook switch 2108 - Lid switch 2109 - AC adapter status updates 2110 - Battery status updates 2111 2112config OLPC_XO15_SCI 2113 bool "OLPC XO-1.5 SCI extras" 2114 depends on OLPC && ACPI 2115 select POWER_SUPPLY 2116 ---help--- 2117 Add support for SCI-based features of the OLPC XO-1.5 laptop: 2118 - EC-driven system wakeups 2119 - AC adapter status updates 2120 - Battery status updates 2121 2122config ALIX 2123 bool "PCEngines ALIX System Support (LED setup)" 2124 select GPIOLIB 2125 ---help--- 2126 This option enables system support for the PCEngines ALIX. 2127 At present this just sets up LEDs for GPIO control on 2128 ALIX2/3/6 boards. However, other system specific setup should 2129 get added here. 2130 2131 Note: You must still enable the drivers for GPIO and LED support 2132 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2133 2134 Note: You have to set alix.force=1 for boards with Award BIOS. 2135 2136endif # X86_32 2137 2138config AMD_NB 2139 def_bool y 2140 depends on CPU_SUP_AMD && PCI 2141 2142source "drivers/pcmcia/Kconfig" 2143 2144source "drivers/pci/hotplug/Kconfig" 2145 2146config RAPIDIO 2147 bool "RapidIO support" 2148 depends on PCI 2149 default n 2150 help 2151 If you say Y here, the kernel will include drivers and 2152 infrastructure code to support RapidIO interconnect devices. 2153 2154source "drivers/rapidio/Kconfig" 2155 2156endmenu 2157 2158 2159menu "Executable file formats / Emulations" 2160 2161source "fs/Kconfig.binfmt" 2162 2163config IA32_EMULATION 2164 bool "IA32 Emulation" 2165 depends on X86_64 2166 select COMPAT_BINFMT_ELF 2167 ---help--- 2168 Include code to run 32-bit programs under a 64-bit kernel. You should 2169 likely turn this on, unless you're 100% sure that you don't have any 2170 32-bit programs left. 2171 2172config IA32_AOUT 2173 tristate "IA32 a.out support" 2174 depends on IA32_EMULATION 2175 ---help--- 2176 Support old a.out binaries in the 32bit emulation. 2177 2178config COMPAT 2179 def_bool y 2180 depends on IA32_EMULATION 2181 2182config COMPAT_FOR_U64_ALIGNMENT 2183 def_bool COMPAT 2184 depends on X86_64 2185 2186config SYSVIPC_COMPAT 2187 def_bool y 2188 depends on COMPAT && SYSVIPC 2189 2190config KEYS_COMPAT 2191 bool 2192 depends on COMPAT && KEYS 2193 default y 2194 2195endmenu 2196 2197 2198config HAVE_ATOMIC_IOMAP 2199 def_bool y 2200 depends on X86_32 2201 2202config HAVE_TEXT_POKE_SMP 2203 bool 2204 select STOP_MACHINE if SMP 2205 2206source "net/Kconfig" 2207 2208source "drivers/Kconfig" 2209 2210source "drivers/firmware/Kconfig" 2211 2212source "fs/Kconfig" 2213 2214source "arch/x86/Kconfig.debug" 2215 2216source "security/Kconfig" 2217 2218source "crypto/Kconfig" 2219 2220source "arch/x86/kvm/Kconfig" 2221 2222source "lib/Kconfig" 2223