1daa93fabSSam Ravnborg# Select 32 or 64 bit 2daa93fabSSam Ravnborgconfig 64BIT 36840999bSSam Ravnborg bool "64-bit kernel" if ARCH = "x86" 4ffee0de4SDavid Woodhouse default ARCH != "i386" 58f9ca475SIngo Molnar ---help--- 6daa93fabSSam Ravnborg Say yes to build a 64-bit kernel - formerly known as x86_64 7daa93fabSSam Ravnborg Say no to build a 32-bit kernel - formerly known as i386 8daa93fabSSam Ravnborg 9daa93fabSSam Ravnborgconfig X86_32 103120e25eSJan Beulich def_bool y 113120e25eSJan Beulich depends on !64BIT 1282491451SRussell King select CLKSRC_I8253 13af1839ebSCatalin Marinas select HAVE_UID16 14daa93fabSSam Ravnborg 15daa93fabSSam Ravnborgconfig X86_64 163120e25eSJan Beulich def_bool y 173120e25eSJan Beulich depends on 64BIT 184692d77fSAlessandro Rubini select X86_DEV_DMA_OPS 19bc08b449SLinus Torvalds select ARCH_USE_CMPXCHG_LOCKREF 201032c0baSSam Ravnborg 211032c0baSSam Ravnborg### Arch settings 228d5fffb9SSam Ravnborgconfig X86 233c2362e6SHarvey Harrison def_bool y 24446f24d1SStephen Boyd select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS 2577fbbc81SMark Salter select ARCH_MIGHT_HAVE_PC_PARPORT 265e2c18c0SMark Salter select ARCH_MIGHT_HAVE_PC_SERIO 27e17c6d56SDavid Woodhouse select HAVE_AOUT if X86_32 28a5574cf6SIngo Molnar select HAVE_UNSTABLE_SCHED_CLOCK 29cbee9f88SPeter Zijlstra select ARCH_SUPPORTS_NUMA_BALANCING 30be5e610cSPeter Zijlstra select ARCH_SUPPORTS_INT128 if X86_64 31cbee9f88SPeter Zijlstra select ARCH_WANTS_PROT_NUMA_PROT_NONE 32ec7748b5SSam Ravnborg select HAVE_IDE 3342d4b839SMathieu Desnoyers select HAVE_OPROFILE 348761f1abSRalf Baechle select HAVE_PCSPKR_PLATFORM 35cc2067a5SPeter Zijlstra select HAVE_PERF_EVENTS 3628b2ee20SRik van Riel select HAVE_IOREMAP_PROT 373f550096SMathieu Desnoyers select HAVE_KPROBES 3872d7c3b3SYinghai Lu select HAVE_MEMBLOCK 390608f70cSTejun Heo select HAVE_MEMBLOCK_NODE_MAP 40c378ddd5STejun Heo select ARCH_DISCARD_MEMBLOCK 411f972768SIngo Molnar select ARCH_WANT_OPTIONAL_GPIOLIB 42da4276b8SIngo Molnar select ARCH_WANT_FRAME_POINTERS 437c095e46SFUJITA Tomonori select HAVE_DMA_ATTRS 440a2b9a6eSMarek Szyprowski select HAVE_DMA_CONTIGUOUS if !SWIOTLB 459edddaa2SAnanth N Mavinakayanahalli select HAVE_KRETPROBES 465b7c73e0SMark Salter select GENERIC_EARLY_IOREMAP 47c0f7ac3aSMasami Hiramatsu select HAVE_OPTPROBES 48e7dbfe34SMasami Hiramatsu select HAVE_KPROBES_ON_FTRACE 49e4b2b886SSteven Rostedt select HAVE_FTRACE_MCOUNT_RECORD 50d57c5d51SSteven Rostedt select HAVE_FENTRY if X86_64 51cf4db259SSteven Rostedt select HAVE_C_RECORDMCOUNT 52677aa9f7SSteven Rostedt select HAVE_DYNAMIC_FTRACE 5306aeaaeaSMasami Hiramatsu select HAVE_DYNAMIC_FTRACE_WITH_REGS 54606576ceSSteven Rostedt select HAVE_FUNCTION_TRACER 5548d68b20SFrederic Weisbecker select HAVE_FUNCTION_GRAPH_TRACER 5671e308a2SSteven Rostedt select HAVE_FUNCTION_GRAPH_FP_TEST 5760a7ecf4SSteven Rostedt select HAVE_FUNCTION_TRACE_MCOUNT_TEST 5866700001SJosh Stone select HAVE_SYSCALL_TRACEPOINTS 597ac57a89SCatalin Marinas select SYSCTL_EXCEPTION_TRACE 60e0ec9483SIngo Molnar select HAVE_KVM 6149793b03SIngo Molnar select HAVE_ARCH_KGDB 6299bbc4b1SRoland McGrath select HAVE_ARCH_TRACEHOOK 63323ec001SDmitry Baryshkov select HAVE_GENERIC_DMA_COHERENT if X86_32 6458340a07SJohannes Berg select HAVE_EFFICIENT_UNALIGNED_ACCESS 658d26487fSTörök Edwin select USER_STACKTRACE_SUPPORT 66f850c30cSHeiko Carstens select HAVE_REGS_AND_STACK_ACCESS_API 672118d0c5SJoerg Roedel select HAVE_DMA_API_DEBUG 682e9f3bddSH. Peter Anvin select HAVE_KERNEL_GZIP 692e9f3bddSH. Peter Anvin select HAVE_KERNEL_BZIP2 702e9f3bddSH. Peter Anvin select HAVE_KERNEL_LZMA 7130314804SLasse Collin select HAVE_KERNEL_XZ 7213510997SAlbin Tonnerre select HAVE_KERNEL_LZO 73f9b493acSKyungsik Lee select HAVE_KERNEL_LZ4 740067f129SK.Prasad select HAVE_HW_BREAKPOINT 750102752eSFrederic Weisbecker select HAVE_MIXED_BREAKPOINTS_REGS 7699e8c5a3SFrederic Weisbecker select PERF_EVENTS 77c01d4323SFrederic Weisbecker select HAVE_PERF_EVENTS_NMI 78c5e63197SJiri Olsa select HAVE_PERF_REGS 79c5ebcedbSJiri Olsa select HAVE_PERF_USER_STACK_DUMP 80b69ec42bSCatalin Marinas select HAVE_DEBUG_KMEMLEAK 8199e8c5a3SFrederic Weisbecker select ANON_INODES 82eb068e78SH. Peter Anvin select HAVE_ALIGNED_STRUCT_PAGE if SLUB 83eb068e78SH. Peter Anvin select HAVE_CMPXCHG_LOCAL 842565409fSHeiko Carstens select HAVE_CMPXCHG_DOUBLE 850a4af3b0SPekka Enberg select HAVE_ARCH_KMEMCHECK 867c68af6eSAvi Kivity select HAVE_USER_RETURN_NOTIFIER 87e39f5602SDavid Daney select ARCH_BINFMT_ELF_RANDOMIZE_PIE 8846eb3b64SSteven Rostedt select HAVE_ARCH_JUMP_LABEL 897463449bSCatalin Marinas select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE 90141d55e6SYinghai Lu select SPARSE_IRQ 91c49aa5bdSJan Beulich select GENERIC_FIND_FIRST_BIT 923bb9808eSThomas Gleixner select GENERIC_IRQ_PROBE 933bb9808eSThomas Gleixner select GENERIC_PENDING_IRQ if SMP 94517e4981SThomas Gleixner select GENERIC_IRQ_SHOW 95d1748302SMartin Schwidefsky select GENERIC_CLOCKEVENTS_MIN_ADJUST 96c0185808SThomas Gleixner select IRQ_FORCED_THREADING 97e47b65b0SSam Ravnborg select HAVE_BPF_JIT if X86_64 9815626062SGerald Schaefer select HAVE_ARCH_TRANSPARENT_HUGEPAGE 990a779c57SThomas Gleixner select CLKEVT_I8253 100df013ffbSHuang Ying select ARCH_HAVE_NMI_SAFE_CMPXCHG 1014673ca8eSMichael S. Tsirkin select GENERIC_IOMAP 102e419b4ccSLinus Torvalds select DCACHE_WORD_ACCESS 1037eb43a6dSThomas Gleixner select GENERIC_SMP_IDLE_THREAD 104c1d7e01dSWill Deacon select ARCH_WANT_IPC_PARSE_VERSION if X86_32 105c6cfbeb4SWill Drewry select HAVE_ARCH_SECCOMP_FILTER 1068b5ad472SDavid Daney select BUILDTIME_EXTABLE_SORT 107bdebaf80SThomas Gleixner select GENERIC_CMOS_UPDATE 1080f8975ecSPavel Emelyanov select HAVE_ARCH_SOFT_DIRTY 109bdebaf80SThomas Gleixner select CLOCKSOURCE_WATCHDOG 110bdebaf80SThomas Gleixner select GENERIC_CLOCKEVENTS 111d2312e33SStefani Seibold select ARCH_CLOCKSOURCE_DATA 112bdebaf80SThomas Gleixner select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 113d2312e33SStefani Seibold select GENERIC_TIME_VSYSCALL 114bdebaf80SThomas Gleixner select KTIME_SCALAR if X86_32 1154ae73f2dSLinus Torvalds select GENERIC_STRNCPY_FROM_USER 1165723aa99SLinus Torvalds select GENERIC_STRNLEN_USER 11791d1aa43SFrederic Weisbecker select HAVE_CONTEXT_TRACKING if X86_64 118fdf9c356SFrederic Weisbecker select HAVE_IRQ_TIME_ACCOUNTING 1194febd95aSStephen Rothwell select VIRT_TO_BUS 120786d35d4SDavid Howells select MODULES_USE_ELF_REL if X86_32 121786d35d4SDavid Howells select MODULES_USE_ELF_RELA if X86_64 1221d4b4b29SAl Viro select CLONE_BACKWARDS if X86_32 12383a57a4dSDavid Woodhouse select ARCH_USE_BUILTIN_BSWAP 12415ce1f71SAl Viro select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION 1255b3eb3adSAl Viro select OLD_SIGACTION if X86_32 1265b3eb3adSAl Viro select COMPAT_OLD_SIGACTION if IA32_EMULATION 1273195ef59SPrarit Bhargava select RTC_LIB 128d1a1dc0bSDave Hansen select HAVE_DEBUG_STACKOVERFLOW 129a2cd11f7SFrederic Weisbecker select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 13019952a92SKees Cook select HAVE_CC_STACKPROTECTOR 1312b9c1f03SArd Biesheuvel select GENERIC_CPU_AUTOPROBE 1327a017721SAKASHI Takahiro select HAVE_ARCH_AUDITSYSCALL 1337d8330a5SBalbir Singh 134ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER 1353120e25eSJan Beulich def_bool y 1363120e25eSJan Beulich depends on KPROBES || PERF_EVENTS || UPROBES 137ba7e4d13SIngo Molnar 13851b26adaSLinus Torvaldsconfig OUTPUT_FORMAT 13951b26adaSLinus Torvalds string 14051b26adaSLinus Torvalds default "elf32-i386" if X86_32 14151b26adaSLinus Torvalds default "elf64-x86-64" if X86_64 14251b26adaSLinus Torvalds 14373531905SSam Ravnborgconfig ARCH_DEFCONFIG 144b9b39bfbSSam Ravnborg string 14573531905SSam Ravnborg default "arch/x86/configs/i386_defconfig" if X86_32 14673531905SSam Ravnborg default "arch/x86/configs/x86_64_defconfig" if X86_64 147b9b39bfbSSam Ravnborg 1488d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT 1493c2362e6SHarvey Harrison def_bool y 1508d5fffb9SSam Ravnborg 1518d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT 1523c2362e6SHarvey Harrison def_bool y 1538d5fffb9SSam Ravnborg 154aa7d9350SHeiko Carstensconfig HAVE_LATENCYTOP_SUPPORT 155aa7d9350SHeiko Carstens def_bool y 156aa7d9350SHeiko Carstens 1578d5fffb9SSam Ravnborgconfig MMU 1583c2362e6SHarvey Harrison def_bool y 1598d5fffb9SSam Ravnborg 1608d5fffb9SSam Ravnborgconfig SBUS 1618d5fffb9SSam Ravnborg bool 1628d5fffb9SSam Ravnborg 1633bc4e459SFUJITA Tomonoriconfig NEED_DMA_MAP_STATE 1643120e25eSJan Beulich def_bool y 1653120e25eSJan Beulich depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG 1663bc4e459SFUJITA Tomonori 16718e98307SFUJITA Tomonoriconfig NEED_SG_DMA_LENGTH 1684a14d84eSAndrew Morton def_bool y 16918e98307SFUJITA Tomonori 1708d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA 1713120e25eSJan Beulich def_bool y 1723120e25eSJan Beulich depends on ISA_DMA_API 1738d5fffb9SSam Ravnborg 1748d5fffb9SSam Ravnborgconfig GENERIC_BUG 1753c2362e6SHarvey Harrison def_bool y 1768d5fffb9SSam Ravnborg depends on BUG 177b93a531eSJan Beulich select GENERIC_BUG_RELATIVE_POINTERS if X86_64 178b93a531eSJan Beulich 179b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS 180b93a531eSJan Beulich bool 1818d5fffb9SSam Ravnborg 1828d5fffb9SSam Ravnborgconfig GENERIC_HWEIGHT 1833c2362e6SHarvey Harrison def_bool y 1848d5fffb9SSam Ravnborg 1858d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC 1863120e25eSJan Beulich def_bool y 1873120e25eSJan Beulich depends on ISA_DMA_API 1888d5fffb9SSam Ravnborg 1891032c0baSSam Ravnborgconfig RWSEM_XCHGADD_ALGORITHM 1903120e25eSJan Beulich def_bool y 1911032c0baSSam Ravnborg 1921032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY 1931032c0baSSam Ravnborg def_bool y 1941032c0baSSam Ravnborg 1959a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX 1969a0b8415Svenkatesh.pallipadi@intel.com def_bool y 1978d5fffb9SSam Ravnborg 1981b27d05bSPekka Enbergconfig ARCH_HAS_CACHE_LINE_SIZE 1991b27d05bSPekka Enberg def_bool y 2001b27d05bSPekka Enberg 201dd5af90aSMike Travisconfig HAVE_SETUP_PER_CPU_AREA 20289c9c4c5SBrian Gerst def_bool y 203b32ef636Stravis@sgi.com 20408fc4580STejun Heoconfig NEED_PER_CPU_EMBED_FIRST_CHUNK 20508fc4580STejun Heo def_bool y 20608fc4580STejun Heo 20708fc4580STejun Heoconfig NEED_PER_CPU_PAGE_FIRST_CHUNK 20811124411STejun Heo def_bool y 20911124411STejun Heo 210801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE 211801e4062SJohannes Berg def_bool y 212801e4062SJohannes Berg 213f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE 214f4cb5700SJohannes Berg def_bool y 215f4cb5700SJohannes Berg 216cfe28c5dSSteve Capperconfig ARCH_WANT_HUGE_PMD_SHARE 217cfe28c5dSSteve Capper def_bool y 218cfe28c5dSSteve Capper 21953313b2cSSteve Capperconfig ARCH_WANT_GENERAL_HUGETLB 22053313b2cSSteve Capper def_bool y 22153313b2cSSteve Capper 2228d5fffb9SSam Ravnborgconfig ZONE_DMA32 2238d5fffb9SSam Ravnborg bool 2248d5fffb9SSam Ravnborg default X86_64 2258d5fffb9SSam Ravnborg 2268d5fffb9SSam Ravnborgconfig AUDIT_ARCH 2278d5fffb9SSam Ravnborg bool 2288d5fffb9SSam Ravnborg default X86_64 2298d5fffb9SSam Ravnborg 230765c68bdSIngo Molnarconfig ARCH_SUPPORTS_OPTIMIZED_INLINING 231765c68bdSIngo Molnar def_bool y 232765c68bdSIngo Molnar 2336a11f75bSAkinobu Mitaconfig ARCH_SUPPORTS_DEBUG_PAGEALLOC 2346a11f75bSAkinobu Mita def_bool y 2356a11f75bSAkinobu Mita 23669575d38SShane Wangconfig HAVE_INTEL_TXT 23769575d38SShane Wang def_bool y 2386ea30386SKees Cook depends on INTEL_IOMMU && ACPI 23969575d38SShane Wang 2406b0c3d44SSam Ravnborgconfig X86_32_SMP 2416b0c3d44SSam Ravnborg def_bool y 2426b0c3d44SSam Ravnborg depends on X86_32 && SMP 2436b0c3d44SSam Ravnborg 2446b0c3d44SSam Ravnborgconfig X86_64_SMP 2456b0c3d44SSam Ravnborg def_bool y 2466b0c3d44SSam Ravnborg depends on X86_64 && SMP 2476b0c3d44SSam Ravnborg 2488d5fffb9SSam Ravnborgconfig X86_HT 2496fc108a0SJan Beulich def_bool y 250ee0011a7SAdrian Bunk depends on SMP 2518d5fffb9SSam Ravnborg 252ccbeed3aSTejun Heoconfig X86_32_LAZY_GS 253ccbeed3aSTejun Heo def_bool y 25460a5317fSTejun Heo depends on X86_32 && !CC_STACKPROTECTOR 255ccbeed3aSTejun Heo 256d61931d8SBorislav Petkovconfig ARCH_HWEIGHT_CFLAGS 257d61931d8SBorislav Petkov string 258d61931d8SBorislav Petkov default "-fcall-saved-ecx -fcall-saved-edx" if X86_32 259d61931d8SBorislav Petkov 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 260d61931d8SBorislav Petkov 2612b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES 2622b144498SSrikar Dronamraju def_bool y 2632b144498SSrikar Dronamraju 264*d20642f0SRob Herringconfig FIX_EARLYCON_MEM 265*d20642f0SRob Herring def_bool y 266*d20642f0SRob Herring 267506f1d07SSam Ravnborgsource "init/Kconfig" 268dc52ddc0SMatt Helsleysource "kernel/Kconfig.freezer" 2698d5fffb9SSam Ravnborg 270506f1d07SSam Ravnborgmenu "Processor type and features" 271506f1d07SSam Ravnborg 2725ee71535SRandy Dunlapconfig ZONE_DMA 2735ee71535SRandy Dunlap bool "DMA memory allocation support" if EXPERT 2745ee71535SRandy Dunlap default y 2755ee71535SRandy Dunlap help 2765ee71535SRandy Dunlap DMA memory allocation support allows devices with less than 32-bit 2775ee71535SRandy Dunlap addressing to allocate within the first 16MB of address space. 2785ee71535SRandy Dunlap Disable if no such devices will be used. 2795ee71535SRandy Dunlap 2805ee71535SRandy Dunlap If unsure, say Y. 2815ee71535SRandy Dunlap 282506f1d07SSam Ravnborgconfig SMP 283506f1d07SSam Ravnborg bool "Symmetric multi-processing support" 284506f1d07SSam Ravnborg ---help--- 285506f1d07SSam Ravnborg This enables support for systems with more than one CPU. If you have 2864a474157SRobert Graffham a system with only one CPU, say N. If you have a system with more 2874a474157SRobert Graffham than one CPU, say Y. 288506f1d07SSam Ravnborg 2894a474157SRobert Graffham If you say N here, the kernel will run on uni- and multiprocessor 290506f1d07SSam Ravnborg machines, but will use only one CPU of a multiprocessor machine. If 291506f1d07SSam Ravnborg you say Y here, the kernel will run on many, but not all, 2924a474157SRobert Graffham uniprocessor machines. On a uniprocessor machine, the kernel 293506f1d07SSam Ravnborg will run faster if you say N here. 294506f1d07SSam Ravnborg 295506f1d07SSam Ravnborg Note that if you say Y here and choose architecture "586" or 296506f1d07SSam Ravnborg "Pentium" under "Processor family", the kernel will not work on 486 297506f1d07SSam Ravnborg architectures. Similarly, multiprocessor kernels for the "PPro" 298506f1d07SSam Ravnborg architecture may not work on all Pentium based boards. 299506f1d07SSam Ravnborg 300506f1d07SSam Ravnborg People using multiprocessor machines who say Y here should also say 301506f1d07SSam Ravnborg Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 302506f1d07SSam Ravnborg Management" code will be disabled if you say Y here. 303506f1d07SSam Ravnborg 304395cf969SPaul Bolle See also <file:Documentation/x86/i386/IO-APIC.txt>, 305506f1d07SSam Ravnborg <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 306506f1d07SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 307506f1d07SSam Ravnborg 308506f1d07SSam Ravnborg If you don't know what to do here, say N. 309506f1d07SSam Ravnborg 31006cd9a7dSYinghai Luconfig X86_X2APIC 31106cd9a7dSYinghai Lu bool "Support x2apic" 312d3f13810SSuresh Siddha depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP 31306cd9a7dSYinghai Lu ---help--- 31406cd9a7dSYinghai Lu This enables x2apic support on CPUs that have this feature. 31506cd9a7dSYinghai Lu 31606cd9a7dSYinghai Lu This allows 32-bit apic IDs (so it can support very large systems), 31706cd9a7dSYinghai Lu and accesses the local apic via MSRs not via mmio. 31806cd9a7dSYinghai Lu 31906cd9a7dSYinghai Lu If you don't know what to do here, say N. 32006cd9a7dSYinghai Lu 3216695c85bSYinghai Luconfig X86_MPPARSE 3226e87f9b7SBin Gao bool "Enable MPS table" if ACPI || SFI 3237a527688SJan Beulich default y 3245ab74722SIngo Molnar depends on X86_LOCAL_APIC 3258f9ca475SIngo Molnar ---help--- 3266695c85bSYinghai Lu For old smp systems that do not have proper acpi support. Newer systems 3276695c85bSYinghai Lu (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 3286695c85bSYinghai Lu 32926f7ef14SYinghai Luconfig X86_BIGSMP 33026f7ef14SYinghai Lu bool "Support for big SMP systems with more than 8 CPUs" 33126f7ef14SYinghai Lu depends on X86_32 && SMP 3328f9ca475SIngo Molnar ---help--- 33326f7ef14SYinghai Lu This option is needed for the systems that have more than 8 CPUs 334506f1d07SSam Ravnborg 335ddd70cf9SJun Nakajimaconfig GOLDFISH 336ddd70cf9SJun Nakajima def_bool y 337ddd70cf9SJun Nakajima depends on X86_GOLDFISH 338ddd70cf9SJun Nakajima 3398425091fSRavikiran G Thirumalaiif X86_32 340c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 341c5c606d9SRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 342c5c606d9SRavikiran G Thirumalai default y 3438f9ca475SIngo Molnar ---help--- 34406ac8346SIngo Molnar If you disable this option then the kernel will only support 34506ac8346SIngo Molnar standard PC platforms. (which covers the vast majority of 34606ac8346SIngo Molnar systems out there.) 34706ac8346SIngo Molnar 3488425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 3498425091fSRavikiran G Thirumalai for the following (non-PC) 32 bit x86 platforms: 350cb7b8023SBen Hutchings Goldfish (Android emulator) 3518425091fSRavikiran G Thirumalai AMD Elan 3528425091fSRavikiran G Thirumalai RDC R-321x SoC 3538425091fSRavikiran G Thirumalai SGI 320/540 (Visual Workstation) 35483125a3aSAlessandro Rubini STA2X11-based (e.g. Northville) 3553f4110a4SThomas Gleixner Moorestown MID devices 35606ac8346SIngo Molnar 35706ac8346SIngo Molnar If you have one of these systems, or if you want to build a 35806ac8346SIngo Molnar generic distribution kernel, say Y here - otherwise say N. 3598425091fSRavikiran G Thirumalaiendif 36006ac8346SIngo Molnar 3618425091fSRavikiran G Thirumalaiif X86_64 3628425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 3638425091fSRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 3648425091fSRavikiran G Thirumalai default y 3658425091fSRavikiran G Thirumalai ---help--- 3668425091fSRavikiran G Thirumalai If you disable this option then the kernel will only support 3678425091fSRavikiran G Thirumalai standard PC platforms. (which covers the vast majority of 3688425091fSRavikiran G Thirumalai systems out there.) 3698425091fSRavikiran G Thirumalai 3708425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 3718425091fSRavikiran G Thirumalai for the following (non-PC) 64 bit x86 platforms: 37244b111b5SSteffen Persvold Numascale NumaChip 3738425091fSRavikiran G Thirumalai ScaleMP vSMP 3748425091fSRavikiran G Thirumalai SGI Ultraviolet 3758425091fSRavikiran G Thirumalai 3768425091fSRavikiran G Thirumalai If you have one of these systems, or if you want to build a 3778425091fSRavikiran G Thirumalai generic distribution kernel, say Y here - otherwise say N. 3788425091fSRavikiran G Thirumalaiendif 379c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms 380c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 38144b111b5SSteffen Persvoldconfig X86_NUMACHIP 38244b111b5SSteffen Persvold bool "Numascale NumaChip" 38344b111b5SSteffen Persvold depends on X86_64 38444b111b5SSteffen Persvold depends on X86_EXTENDED_PLATFORM 38544b111b5SSteffen Persvold depends on NUMA 38644b111b5SSteffen Persvold depends on SMP 38744b111b5SSteffen Persvold depends on X86_X2APIC 388f9726bfdSDaniel J Blueman depends on PCI_MMCONFIG 38944b111b5SSteffen Persvold ---help--- 39044b111b5SSteffen Persvold Adds support for Numascale NumaChip large-SMP systems. Needed to 39144b111b5SSteffen Persvold enable more than ~168 cores. 39244b111b5SSteffen Persvold If you don't have one of these, you should say N here. 39303b48632SNick Piggin 3946a48565eSIngo Molnarconfig X86_VSMP 395c5c606d9SRavikiran G Thirumalai bool "ScaleMP vSMP" 3966276a074SBorislav Petkov select HYPERVISOR_GUEST 3976a48565eSIngo Molnar select PARAVIRT 3986a48565eSIngo Molnar depends on X86_64 && PCI 399c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 400ead91d4bSShai Fultheim depends on SMP 4018f9ca475SIngo Molnar ---help--- 4026a48565eSIngo Molnar Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 4036a48565eSIngo Molnar supposed to run on these EM64T-based machines. Only choose this option 4046a48565eSIngo Molnar if you have one of these machines. 4056a48565eSIngo Molnar 406c5c606d9SRavikiran G Thirumalaiconfig X86_UV 407c5c606d9SRavikiran G Thirumalai bool "SGI Ultraviolet" 408c5c606d9SRavikiran G Thirumalai depends on X86_64 409c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 41054c28d29SJack Steiner depends on NUMA 4119d6c26e7SSuresh Siddha depends on X86_X2APIC 412c5c606d9SRavikiran G Thirumalai ---help--- 413c5c606d9SRavikiran G Thirumalai This option is needed in order to support SGI Ultraviolet systems. 414c5c606d9SRavikiran G Thirumalai If you don't have one of these, you should say N here. 415c5c606d9SRavikiran G Thirumalai 416c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms 417c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 418506f1d07SSam Ravnborg 419ddd70cf9SJun Nakajimaconfig X86_GOLDFISH 420ddd70cf9SJun Nakajima bool "Goldfish (Virtual Platform)" 421ddd70cf9SJun Nakajima depends on X86_32 422cb7b8023SBen Hutchings depends on X86_EXTENDED_PLATFORM 423ddd70cf9SJun Nakajima ---help--- 424ddd70cf9SJun Nakajima Enable support for the Goldfish virtual platform used primarily 425ddd70cf9SJun Nakajima for Android development. Unless you are building for the Android 426ddd70cf9SJun Nakajima Goldfish emulator say N here. 427ddd70cf9SJun Nakajima 428c751e17bSThomas Gleixnerconfig X86_INTEL_CE 429c751e17bSThomas Gleixner bool "CE4100 TV platform" 430c751e17bSThomas Gleixner depends on PCI 431c751e17bSThomas Gleixner depends on PCI_GODIRECT 432c751e17bSThomas Gleixner depends on X86_32 433c751e17bSThomas Gleixner depends on X86_EXTENDED_PLATFORM 43437bc9f50SDirk Brandewie select X86_REBOOTFIXUPS 435da6b737bSSebastian Andrzej Siewior select OF 436da6b737bSSebastian Andrzej Siewior select OF_EARLY_FLATTREE 437b4e51854SGrant Likely select IRQ_DOMAIN 438c751e17bSThomas Gleixner ---help--- 439c751e17bSThomas Gleixner Select for the Intel CE media processor (CE4100) SOC. 440c751e17bSThomas Gleixner This option compiles in support for the CE4100 SOC for settop 441c751e17bSThomas Gleixner boxes and media devices. 442c751e17bSThomas Gleixner 4434cb9b00fSDavid Cohenconfig X86_INTEL_MID 44443605ef1SAlan Cox bool "Intel MID platform support" 44543605ef1SAlan Cox depends on X86_32 44643605ef1SAlan Cox depends on X86_EXTENDED_PLATFORM 447edc6bc78SDavid Cohen depends on X86_PLATFORM_DEVICES 4481ea7c673SAlan Cox depends on PCI 4491ea7c673SAlan Cox depends on PCI_GOANY 4501ea7c673SAlan Cox depends on X86_IO_APIC 4517c9c3a1eSAlan Cox select SFI 4524cb9b00fSDavid Cohen select I2C 4537c9c3a1eSAlan Cox select DW_APB_TIMER 4541ea7c673SAlan Cox select APB_TIMER 4551ea7c673SAlan Cox select INTEL_SCU_IPC 45615a713dfSMika Westerberg select MFD_INTEL_MSIC 4571ea7c673SAlan Cox ---help--- 4584cb9b00fSDavid Cohen Select to build a kernel capable of supporting Intel MID (Mobile 4594cb9b00fSDavid Cohen Internet Device) platform systems which do not have the PCI legacy 4604cb9b00fSDavid Cohen interfaces. If you are building for a PC class system say N here. 4611ea7c673SAlan Cox 4624cb9b00fSDavid Cohen Intel MID platforms are based on an Intel processor and chipset which 4634cb9b00fSDavid Cohen consume less power than most of the x86 derivatives. 46443605ef1SAlan Cox 4653d48aab1SMika Westerbergconfig X86_INTEL_LPSS 4663d48aab1SMika Westerberg bool "Intel Low Power Subsystem Support" 4673d48aab1SMika Westerberg depends on ACPI 4683d48aab1SMika Westerberg select COMMON_CLK 4690f531431SMathias Nyman select PINCTRL 4703d48aab1SMika Westerberg ---help--- 4713d48aab1SMika Westerberg Select to build support for Intel Low Power Subsystem such as 4723d48aab1SMika Westerberg found on Intel Lynxpoint PCH. Selecting this option enables 4730f531431SMathias Nyman things like clock tree (common clock framework) and pincontrol 4740f531431SMathias Nyman which are needed by the LPSS peripheral drivers. 4753d48aab1SMika Westerberg 476c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X 477c5c606d9SRavikiran G Thirumalai bool "RDC R-321x SoC" 478506f1d07SSam Ravnborg depends on X86_32 479c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 480c5c606d9SRavikiran G Thirumalai select M486 481c5c606d9SRavikiran G Thirumalai select X86_REBOOTFIXUPS 482c5c606d9SRavikiran G Thirumalai ---help--- 483c5c606d9SRavikiran G Thirumalai This option is needed for RDC R-321x system-on-chip, also known 484c5c606d9SRavikiran G Thirumalai as R-8610-(G). 485c5c606d9SRavikiran G Thirumalai If you don't have one of these chips, you should say N here. 486c5c606d9SRavikiran G Thirumalai 487e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD 4889c398017SIngo Molnar bool "Support non-standard 32-bit SMP architectures" 4899c398017SIngo Molnar depends on X86_32 && SMP 490c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 4918f9ca475SIngo Molnar ---help--- 492b5660ba7SH. Peter Anvin This option compiles in the bigsmp and STA2X11 default 493b5660ba7SH. Peter Anvin subarchitectures. It is intended for a generic binary 494b5660ba7SH. Peter Anvin kernel. If you select them all, kernel will probe it one by 495b5660ba7SH. Peter Anvin one and will fallback to default. 496d49c4288SYinghai Lu 497c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms 498d49c4288SYinghai Lu 499d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE 5006fc108a0SJan Beulich def_bool y 501d949f36fSLinus Torvalds # MCE code calls memory_failure(): 502d949f36fSLinus Torvalds depends on X86_MCE 503d949f36fSLinus Torvalds # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 504d949f36fSLinus Torvalds # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 505d949f36fSLinus Torvalds depends on X86_64 || !SPARSEMEM 506d949f36fSLinus Torvalds select ARCH_SUPPORTS_MEMORY_FAILURE 507d949f36fSLinus Torvalds 50883125a3aSAlessandro Rubiniconfig STA2X11 50983125a3aSAlessandro Rubini bool "STA2X11 Companion Chip Support" 51083125a3aSAlessandro Rubini depends on X86_32_NON_STANDARD && PCI 51183125a3aSAlessandro Rubini select X86_DEV_DMA_OPS 51283125a3aSAlessandro Rubini select X86_DMA_REMAP 51383125a3aSAlessandro Rubini select SWIOTLB 51483125a3aSAlessandro Rubini select MFD_STA2X11 51583125a3aSAlessandro Rubini select ARCH_REQUIRE_GPIOLIB 51683125a3aSAlessandro Rubini default n 51783125a3aSAlessandro Rubini ---help--- 51883125a3aSAlessandro Rubini This adds support for boards based on the STA2X11 IO-Hub, 51983125a3aSAlessandro Rubini a.k.a. "ConneXt". The chip is used in place of the standard 52083125a3aSAlessandro Rubini PC chipset, so all "standard" peripherals are missing. If this 52183125a3aSAlessandro Rubini option is selected the kernel will still be able to boot on 52283125a3aSAlessandro Rubini standard PC machines. 52383125a3aSAlessandro Rubini 52482148d1dSShérabconfig X86_32_IRIS 52582148d1dSShérab tristate "Eurobraille/Iris poweroff module" 52682148d1dSShérab depends on X86_32 52782148d1dSShérab ---help--- 52882148d1dSShérab The Iris machines from EuroBraille do not have APM or ACPI support 52982148d1dSShérab to shut themselves down properly. A special I/O sequence is 53082148d1dSShérab needed to do so, which is what this module does at 53182148d1dSShérab kernel shutdown. 53282148d1dSShérab 53382148d1dSShérab This is only for Iris machines from EuroBraille. 53482148d1dSShérab 53582148d1dSShérab If unused, say N. 53682148d1dSShérab 537ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER 5383c2362e6SHarvey Harrison def_bool y 5393c2362e6SHarvey Harrison prompt "Single-depth WCHAN output" 540a87d0914SKen Chen depends on X86 5418f9ca475SIngo Molnar ---help--- 542506f1d07SSam Ravnborg Calculate simpler /proc/<PID>/wchan values. If this option 543506f1d07SSam Ravnborg is disabled then wchan values will recurse back to the 544506f1d07SSam Ravnborg caller function. This provides more accurate wchan values, 545506f1d07SSam Ravnborg at the expense of slightly more scheduling overhead. 546506f1d07SSam Ravnborg 547506f1d07SSam Ravnborg If in doubt, say "Y". 548506f1d07SSam Ravnborg 5496276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST 5506276a074SBorislav Petkov bool "Linux guest support" 5518f9ca475SIngo Molnar ---help--- 5526276a074SBorislav Petkov Say Y here to enable options for running Linux under various hyper- 5536276a074SBorislav Petkov visors. This option enables basic hypervisor detection and platform 5546276a074SBorislav Petkov setup. 555506f1d07SSam Ravnborg 5566276a074SBorislav Petkov If you say N, all options in this submenu will be skipped and 5576276a074SBorislav Petkov disabled, and Linux guest support won't be built in. 558506f1d07SSam Ravnborg 5596276a074SBorislav Petkovif HYPERVISOR_GUEST 560506f1d07SSam Ravnborg 561e61bd94aSEduardo Pereira Habkostconfig PARAVIRT 562e61bd94aSEduardo Pereira Habkost bool "Enable paravirtualization code" 5638f9ca475SIngo Molnar ---help--- 564e61bd94aSEduardo Pereira Habkost This changes the kernel so it can modify itself when it is run 565e61bd94aSEduardo Pereira Habkost under a hypervisor, potentially improving performance significantly 566e61bd94aSEduardo Pereira Habkost over full virtualization. However, when run without a hypervisor 567e61bd94aSEduardo Pereira Habkost the kernel is theoretically slower and slightly larger. 568e61bd94aSEduardo Pereira Habkost 5696276a074SBorislav Petkovconfig PARAVIRT_DEBUG 5706276a074SBorislav Petkov bool "paravirt-ops debugging" 5716276a074SBorislav Petkov depends on PARAVIRT && DEBUG_KERNEL 5726276a074SBorislav Petkov ---help--- 5736276a074SBorislav Petkov Enable to debug paravirt_ops internals. Specifically, BUG if 5746276a074SBorislav Petkov a paravirt_op is missing when it is called. 5756276a074SBorislav Petkov 576b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS 577b4ecc126SJeremy Fitzhardinge bool "Paravirtualization layer for spinlocks" 5786ea30386SKees Cook depends on PARAVIRT && SMP 5798db73266SRaghavendra K T select UNINLINE_SPIN_UNLOCK 580b4ecc126SJeremy Fitzhardinge ---help--- 581b4ecc126SJeremy Fitzhardinge Paravirtualized spinlocks allow a pvops backend to replace the 582b4ecc126SJeremy Fitzhardinge spinlock implementation with something virtualization-friendly 583b4ecc126SJeremy Fitzhardinge (for example, block the virtual CPU rather than spinning). 584b4ecc126SJeremy Fitzhardinge 5854c4e4f61SRaghavendra K T It has a minimal impact on native kernels and gives a nice performance 5864c4e4f61SRaghavendra K T benefit on paravirtualized KVM / Xen kernels. 587b4ecc126SJeremy Fitzhardinge 5884c4e4f61SRaghavendra K T If you are unsure how to answer this question, answer Y. 589b4ecc126SJeremy Fitzhardinge 5906276a074SBorislav Petkovsource "arch/x86/xen/Kconfig" 5916276a074SBorislav Petkov 5926276a074SBorislav Petkovconfig KVM_GUEST 5936276a074SBorislav Petkov bool "KVM Guest support (including kvmclock)" 5946276a074SBorislav Petkov depends on PARAVIRT 5956276a074SBorislav Petkov select PARAVIRT_CLOCK 5966276a074SBorislav Petkov default y 5976276a074SBorislav Petkov ---help--- 5986276a074SBorislav Petkov This option enables various optimizations for running under the KVM 5996276a074SBorislav Petkov hypervisor. It includes a paravirtualized clock, so that instead 6006276a074SBorislav Petkov of relying on a PIT (or probably other) emulation by the 6016276a074SBorislav Petkov underlying device model, the host provides the guest with 6026276a074SBorislav Petkov timing infrastructure such as time of day, and system time 6036276a074SBorislav Petkov 6041e20eb85SSrivatsa Vaddagiriconfig KVM_DEBUG_FS 6051e20eb85SSrivatsa Vaddagiri bool "Enable debug information for KVM Guests in debugfs" 6061e20eb85SSrivatsa Vaddagiri depends on KVM_GUEST && DEBUG_FS 6071e20eb85SSrivatsa Vaddagiri default n 6081e20eb85SSrivatsa Vaddagiri ---help--- 6091e20eb85SSrivatsa Vaddagiri This option enables collection of various statistics for KVM guest. 6101e20eb85SSrivatsa Vaddagiri Statistics are displayed in debugfs filesystem. Enabling this option 6111e20eb85SSrivatsa Vaddagiri may incur significant overhead. 6121e20eb85SSrivatsa Vaddagiri 6136276a074SBorislav Petkovsource "arch/x86/lguest/Kconfig" 6146276a074SBorislav Petkov 6156276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING 6166276a074SBorislav Petkov bool "Paravirtual steal time accounting" 6176276a074SBorislav Petkov depends on PARAVIRT 6186276a074SBorislav Petkov default n 6196276a074SBorislav Petkov ---help--- 6206276a074SBorislav Petkov Select this option to enable fine granularity task steal time 6216276a074SBorislav Petkov accounting. Time spent executing other tasks in parallel with 6226276a074SBorislav Petkov the current vCPU is discounted from the vCPU power. To account for 6236276a074SBorislav Petkov that, there can be a small performance impact. 6246276a074SBorislav Petkov 6256276a074SBorislav Petkov If in doubt, say N here. 6266276a074SBorislav Petkov 6277af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK 6287af192c9SGerd Hoffmann bool 6297af192c9SGerd Hoffmann 6306276a074SBorislav Petkovendif #HYPERVISOR_GUEST 63197349135SJeremy Fitzhardinge 63208677214SYinghai Luconfig NO_BOOTMEM 633774ea0bcSYinghai Lu def_bool y 63408677214SYinghai Lu 63503273184SYinghai Luconfig MEMTEST 63603273184SYinghai Lu bool "Memtest" 6378f9ca475SIngo Molnar ---help--- 638c64df707SYinghai Lu This option adds a kernel parameter 'memtest', which allows memtest 63903273184SYinghai Lu to be set. 64003273184SYinghai Lu memtest=0, mean disabled; -- default 64103273184SYinghai Lu memtest=1, mean do 1 test pattern; 64203273184SYinghai Lu ... 64303273184SYinghai Lu memtest=4, mean do 4 test patterns. 644aba3728cSThomas Gleixner If you are unsure how to answer this question, answer N. 645506f1d07SSam Ravnborg 646506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu" 647506f1d07SSam Ravnborg 648506f1d07SSam Ravnborgconfig HPET_TIMER 6493c2362e6SHarvey Harrison def_bool X86_64 650506f1d07SSam Ravnborg prompt "HPET Timer Support" if X86_32 6518f9ca475SIngo Molnar ---help--- 652506f1d07SSam Ravnborg Use the IA-PC HPET (High Precision Event Timer) to manage 653506f1d07SSam Ravnborg time in preference to the PIT and RTC, if a HPET is 654506f1d07SSam Ravnborg present. 655506f1d07SSam Ravnborg HPET is the next generation timer replacing legacy 8254s. 656506f1d07SSam Ravnborg The HPET provides a stable time base on SMP 657506f1d07SSam Ravnborg systems, unlike the TSC, but it is more expensive to access, 658506f1d07SSam Ravnborg as it is off-chip. You can find the HPET spec at 659e45f2c07SDenis V. Lunev <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>. 660506f1d07SSam Ravnborg 661506f1d07SSam Ravnborg You can safely choose Y here. However, HPET will only be 662506f1d07SSam Ravnborg activated if the platform and the BIOS support this feature. 663506f1d07SSam Ravnborg Otherwise the 8254 will be used for timing services. 664506f1d07SSam Ravnborg 665506f1d07SSam Ravnborg Choose N to continue using the legacy 8254 timer. 666506f1d07SSam Ravnborg 667506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC 6683c2362e6SHarvey Harrison def_bool y 6699d8af78bSBernhard Walle depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 670506f1d07SSam Ravnborg 671bb24c471SJacob Panconfig APB_TIMER 672933b9463SAlan Cox def_bool y if X86_INTEL_MID 673933b9463SAlan Cox prompt "Intel MID APB Timer Support" if X86_INTEL_MID 67406c3df49SJamie Iles select DW_APB_TIMER 675a0c3832aSAlan Cox depends on X86_INTEL_MID && SFI 676bb24c471SJacob Pan help 677bb24c471SJacob Pan APB timer is the replacement for 8254, HPET on X86 MID platforms. 678bb24c471SJacob Pan The APBT provides a stable time base on SMP 679bb24c471SJacob Pan systems, unlike the TSC, but it is more expensive to access, 680bb24c471SJacob Pan as it is off-chip. APB timers are always running regardless of CPU 681bb24c471SJacob Pan C states, they are used as per CPU clockevent device when possible. 682bb24c471SJacob Pan 6836a108a14SDavid Rientjes# Mark as expert because too many people got it wrong. 684506f1d07SSam Ravnborg# The code disables itself when not needed. 6857ae9392cSThomas Petazzoniconfig DMI 6867ae9392cSThomas Petazzoni default y 687cf074402SArd Biesheuvel select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 6886a108a14SDavid Rientjes bool "Enable DMI scanning" if EXPERT 6898f9ca475SIngo Molnar ---help--- 6907ae9392cSThomas Petazzoni Enabled scanning of DMI to identify machine quirks. Say Y 6917ae9392cSThomas Petazzoni here unless you have verified that your setup is not 6927ae9392cSThomas Petazzoni affected by entries in the DMI blacklist. Required by PNP 6937ae9392cSThomas Petazzoni BIOS code. 6947ae9392cSThomas Petazzoni 695506f1d07SSam Ravnborgconfig GART_IOMMU 69638901f1cSAndi Kleen bool "Old AMD GART IOMMU support" 697506f1d07SSam Ravnborg select SWIOTLB 69823ac4ae8SAndreas Herrmann depends on X86_64 && PCI && AMD_NB 6998f9ca475SIngo Molnar ---help--- 700ced3c42cSIngo Molnar Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 701ced3c42cSIngo Molnar GART based hardware IOMMUs. 702ced3c42cSIngo Molnar 703ced3c42cSIngo Molnar The GART supports full DMA access for devices with 32-bit access 704ced3c42cSIngo Molnar limitations, on systems with more than 3 GB. This is usually needed 705ced3c42cSIngo Molnar for USB, sound, many IDE/SATA chipsets and some other devices. 706ced3c42cSIngo Molnar 707ced3c42cSIngo Molnar Newer systems typically have a modern AMD IOMMU, supported via 708ced3c42cSIngo Molnar the CONFIG_AMD_IOMMU=y config option. 709ced3c42cSIngo Molnar 710ced3c42cSIngo Molnar In normal configurations this driver is only active when needed: 711ced3c42cSIngo Molnar there's more than 3 GB of memory and the system contains a 712ced3c42cSIngo Molnar 32-bit limited device. 713ced3c42cSIngo Molnar 714ced3c42cSIngo Molnar If unsure, say Y. 715506f1d07SSam Ravnborg 716506f1d07SSam Ravnborgconfig CALGARY_IOMMU 717506f1d07SSam Ravnborg bool "IBM Calgary IOMMU support" 718506f1d07SSam Ravnborg select SWIOTLB 7196ea30386SKees Cook depends on X86_64 && PCI 7208f9ca475SIngo Molnar ---help--- 721506f1d07SSam Ravnborg Support for hardware IOMMUs in IBM's xSeries x366 and x460 722506f1d07SSam Ravnborg systems. Needed to run systems with more than 3GB of memory 723506f1d07SSam Ravnborg properly with 32-bit PCI devices that do not support DAC 724506f1d07SSam Ravnborg (Double Address Cycle). Calgary also supports bus level 725506f1d07SSam Ravnborg isolation, where all DMAs pass through the IOMMU. This 726506f1d07SSam Ravnborg prevents them from going anywhere except their intended 727506f1d07SSam Ravnborg destination. This catches hard-to-find kernel bugs and 728506f1d07SSam Ravnborg mis-behaving drivers and devices that do not use the DMA-API 729506f1d07SSam Ravnborg properly to set up their DMA buffers. The IOMMU can be 730506f1d07SSam Ravnborg turned off at boot time with the iommu=off parameter. 731506f1d07SSam Ravnborg Normally the kernel will make the right choice by itself. 732506f1d07SSam Ravnborg If unsure, say Y. 733506f1d07SSam Ravnborg 734506f1d07SSam Ravnborgconfig CALGARY_IOMMU_ENABLED_BY_DEFAULT 7353c2362e6SHarvey Harrison def_bool y 7363c2362e6SHarvey Harrison prompt "Should Calgary be enabled by default?" 737506f1d07SSam Ravnborg depends on CALGARY_IOMMU 7388f9ca475SIngo Molnar ---help--- 739506f1d07SSam Ravnborg Should Calgary be enabled by default? if you choose 'y', Calgary 740506f1d07SSam Ravnborg will be used (if it exists). If you choose 'n', Calgary will not be 741506f1d07SSam Ravnborg used even if it exists. If you choose 'n' and would like to use 742506f1d07SSam Ravnborg Calgary anyway, pass 'iommu=calgary' on the kernel command line. 743506f1d07SSam Ravnborg If unsure, say Y. 744506f1d07SSam Ravnborg 745506f1d07SSam Ravnborg# need this always selected by IOMMU for the VIA workaround 746506f1d07SSam Ravnborgconfig SWIOTLB 747a1afd01cSJoerg Roedel def_bool y if X86_64 7488f9ca475SIngo Molnar ---help--- 749506f1d07SSam Ravnborg Support for software bounce buffers used on x86-64 systems 7504454d327SJoe Millenbach which don't have a hardware IOMMU. Using this PCI devices 7514454d327SJoe Millenbach which can only access 32-bits of memory can be used on systems 7524454d327SJoe Millenbach with more than 3 GB of memory. 7534454d327SJoe Millenbach If unsure, say Y. 754506f1d07SSam Ravnborg 755a8522509SFUJITA Tomonoriconfig IOMMU_HELPER 7563120e25eSJan Beulich def_bool y 7573120e25eSJan Beulich depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 758d25e26b6SLinus Torvalds 7591184dc2fSMike Travisconfig MAXSMP 760ddb0c5a6SSamuel Thibault bool "Enable Maximum number of SMP Processors and NUMA Nodes" 7616ea30386SKees Cook depends on X86_64 && SMP && DEBUG_KERNEL 76236f5101aSMike Travis select CPUMASK_OFFSTACK 7638f9ca475SIngo Molnar ---help--- 764ddb0c5a6SSamuel Thibault Enable maximum number of CPUS and NUMA Nodes for this architecture. 7651184dc2fSMike Travis If unsure, say N. 766506f1d07SSam Ravnborg 767506f1d07SSam Ravnborgconfig NR_CPUS 76836f5101aSMike Travis int "Maximum number of CPUs" if SMP && !MAXSMP 7692a3313f4SMichael K. Johnson range 2 8 if SMP && X86_32 && !X86_BIGSMP 770bb61ccc7SJosh Boyer range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK 771b53b5edaSJosh Boyer range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64 77278637a97SMike Travis default "1" if !SMP 773b53b5edaSJosh Boyer default "8192" if MAXSMP 774b5660ba7SH. Peter Anvin default "32" if SMP && X86_BIGSMP 77578637a97SMike Travis default "8" if SMP 7768f9ca475SIngo Molnar ---help--- 777506f1d07SSam Ravnborg This allows you to specify the maximum number of CPUs which this 778bb61ccc7SJosh Boyer kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 779bb61ccc7SJosh Boyer supported value is 4096, otherwise the maximum value is 512. The 780506f1d07SSam Ravnborg minimum value which makes sense is 2. 781506f1d07SSam Ravnborg 782506f1d07SSam Ravnborg This is purely to save memory - each supported CPU adds 783506f1d07SSam Ravnborg approximately eight kilobytes to the kernel image. 784506f1d07SSam Ravnborg 785506f1d07SSam Ravnborgconfig SCHED_SMT 786506f1d07SSam Ravnborg bool "SMT (Hyperthreading) scheduler support" 787b089c12bSHiroshi Shimamoto depends on X86_HT 7888f9ca475SIngo Molnar ---help--- 789506f1d07SSam Ravnborg SMT scheduler support improves the CPU scheduler's decision making 790506f1d07SSam Ravnborg when dealing with Intel Pentium 4 chips with HyperThreading at a 791506f1d07SSam Ravnborg cost of slightly increased overhead in some places. If unsure say 792506f1d07SSam Ravnborg N here. 793506f1d07SSam Ravnborg 794506f1d07SSam Ravnborgconfig SCHED_MC 7953c2362e6SHarvey Harrison def_bool y 7963c2362e6SHarvey Harrison prompt "Multi-core scheduler support" 797b089c12bSHiroshi Shimamoto depends on X86_HT 7988f9ca475SIngo Molnar ---help--- 799506f1d07SSam Ravnborg Multi-core scheduler support improves the CPU scheduler's decision 800506f1d07SSam Ravnborg making when dealing with multi-core CPU chips at a cost of slightly 801506f1d07SSam Ravnborg increased overhead in some places. If unsure say N here. 802506f1d07SSam Ravnborg 803506f1d07SSam Ravnborgsource "kernel/Kconfig.preempt" 804506f1d07SSam Ravnborg 805506f1d07SSam Ravnborgconfig X86_UP_APIC 806506f1d07SSam Ravnborg bool "Local APIC support on uniprocessors" 8070dbc6078SThomas Petazzoni depends on X86_32 && !SMP && !X86_32_NON_STANDARD && !PCI_MSI 8088f9ca475SIngo Molnar ---help--- 809506f1d07SSam Ravnborg A local APIC (Advanced Programmable Interrupt Controller) is an 810506f1d07SSam Ravnborg integrated interrupt controller in the CPU. If you have a single-CPU 811506f1d07SSam Ravnborg system which has a processor with a local APIC, you can say Y here to 812506f1d07SSam Ravnborg enable and use it. If you say Y here even though your machine doesn't 813506f1d07SSam Ravnborg have a local APIC, then the kernel will still run with no slowdown at 814506f1d07SSam Ravnborg all. The local APIC supports CPU-generated self-interrupts (timer, 815506f1d07SSam Ravnborg performance counters), and the NMI watchdog which detects hard 816506f1d07SSam Ravnborg lockups. 817506f1d07SSam Ravnborg 818506f1d07SSam Ravnborgconfig X86_UP_IOAPIC 819506f1d07SSam Ravnborg bool "IO-APIC support on uniprocessors" 820506f1d07SSam Ravnborg depends on X86_UP_APIC 8218f9ca475SIngo Molnar ---help--- 822506f1d07SSam Ravnborg An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 823506f1d07SSam Ravnborg SMP-capable replacement for PC-style interrupt controllers. Most 824506f1d07SSam Ravnborg SMP systems and many recent uniprocessor systems have one. 825506f1d07SSam Ravnborg 826506f1d07SSam Ravnborg If you have a single-CPU system with an IO-APIC, you can say Y here 827506f1d07SSam Ravnborg to use it. If you say Y here even though your machine doesn't have 828506f1d07SSam Ravnborg an IO-APIC, then the kernel will still run with no slowdown at all. 829506f1d07SSam Ravnborg 830506f1d07SSam Ravnborgconfig X86_LOCAL_APIC 8313c2362e6SHarvey Harrison def_bool y 8320dbc6078SThomas Petazzoni depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 833506f1d07SSam Ravnborg 834506f1d07SSam Ravnborgconfig X86_IO_APIC 8353c2362e6SHarvey Harrison def_bool y 8360dbc6078SThomas Petazzoni depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_IOAPIC || PCI_MSI 837506f1d07SSam Ravnborg 83841b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS 83941b9eb26SStefan Assmann bool "Reroute for broken boot IRQs" 84041b9eb26SStefan Assmann depends on X86_IO_APIC 8418f9ca475SIngo Molnar ---help--- 84241b9eb26SStefan Assmann This option enables a workaround that fixes a source of 84341b9eb26SStefan Assmann spurious interrupts. This is recommended when threaded 84441b9eb26SStefan Assmann interrupt handling is used on systems where the generation of 84541b9eb26SStefan Assmann superfluous "boot interrupts" cannot be disabled. 84641b9eb26SStefan Assmann 84741b9eb26SStefan Assmann Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 84841b9eb26SStefan Assmann entry in the chipset's IO-APIC is masked (as, e.g. the RT 84941b9eb26SStefan Assmann kernel does during interrupt handling). On chipsets where this 85041b9eb26SStefan Assmann boot IRQ generation cannot be disabled, this workaround keeps 85141b9eb26SStefan Assmann the original IRQ line masked so that only the equivalent "boot 85241b9eb26SStefan Assmann IRQ" is delivered to the CPUs. The workaround also tells the 85341b9eb26SStefan Assmann kernel to set up the IRQ handler on the boot IRQ line. In this 85441b9eb26SStefan Assmann way only one interrupt is delivered to the kernel. Otherwise 85541b9eb26SStefan Assmann the spurious second interrupt may cause the kernel to bring 85641b9eb26SStefan Assmann down (vital) interrupt lines. 85741b9eb26SStefan Assmann 85841b9eb26SStefan Assmann Only affects "broken" chipsets. Interrupt sharing may be 85941b9eb26SStefan Assmann increased on these systems. 86041b9eb26SStefan Assmann 861506f1d07SSam Ravnborgconfig X86_MCE 862bab9bc65SAndi Kleen bool "Machine Check / overheating reporting" 863e57dbaf7SBorislav Petkov default y 864506f1d07SSam Ravnborg ---help--- 865bab9bc65SAndi Kleen Machine Check support allows the processor to notify the 866bab9bc65SAndi Kleen kernel if it detects a problem (e.g. overheating, data corruption). 867506f1d07SSam Ravnborg The action the kernel takes depends on the severity of the problem, 868bab9bc65SAndi Kleen ranging from warning messages to halting the machine. 8694efc0670SAndi Kleen 870506f1d07SSam Ravnborgconfig X86_MCE_INTEL 8713c2362e6SHarvey Harrison def_bool y 8723c2362e6SHarvey Harrison prompt "Intel MCE features" 873c1ebf835SAndi Kleen depends on X86_MCE && X86_LOCAL_APIC 8748f9ca475SIngo Molnar ---help--- 875506f1d07SSam Ravnborg Additional support for intel specific MCE features such as 876506f1d07SSam Ravnborg the thermal monitor. 877506f1d07SSam Ravnborg 878506f1d07SSam Ravnborgconfig X86_MCE_AMD 8793c2362e6SHarvey Harrison def_bool y 8803c2362e6SHarvey Harrison prompt "AMD MCE features" 881c1ebf835SAndi Kleen depends on X86_MCE && X86_LOCAL_APIC 8828f9ca475SIngo Molnar ---help--- 883506f1d07SSam Ravnborg Additional support for AMD specific MCE features such as 884506f1d07SSam Ravnborg the DRAM Error Threshold. 885506f1d07SSam Ravnborg 8864efc0670SAndi Kleenconfig X86_ANCIENT_MCE 8876fc108a0SJan Beulich bool "Support for old Pentium 5 / WinChip machine checks" 888c31d9633SAndi Kleen depends on X86_32 && X86_MCE 8894efc0670SAndi Kleen ---help--- 8904efc0670SAndi Kleen Include support for machine check handling on old Pentium 5 or WinChip 8915065a706SMasanari Iida systems. These typically need to be enabled explicitly on the command 8924efc0670SAndi Kleen line. 8934efc0670SAndi Kleen 894b2762686SAndi Kleenconfig X86_MCE_THRESHOLD 895b2762686SAndi Kleen depends on X86_MCE_AMD || X86_MCE_INTEL 8966fc108a0SJan Beulich def_bool y 897b2762686SAndi Kleen 898ea149b36SAndi Kleenconfig X86_MCE_INJECT 899c1ebf835SAndi Kleen depends on X86_MCE 900ea149b36SAndi Kleen tristate "Machine check injector support" 901ea149b36SAndi Kleen ---help--- 902ea149b36SAndi Kleen Provide support for injecting machine checks for testing purposes. 903ea149b36SAndi Kleen If you don't know what a machine check is and you don't do kernel 904ea149b36SAndi Kleen QA it is safe to say n. 905ea149b36SAndi Kleen 9064efc0670SAndi Kleenconfig X86_THERMAL_VECTOR 9074efc0670SAndi Kleen def_bool y 9085bb38adcSAndi Kleen depends on X86_MCE_INTEL 9094efc0670SAndi Kleen 910506f1d07SSam Ravnborgconfig VM86 9116a108a14SDavid Rientjes bool "Enable VM86 support" if EXPERT 912506f1d07SSam Ravnborg default y 913506f1d07SSam Ravnborg depends on X86_32 9148f9ca475SIngo Molnar ---help--- 915506f1d07SSam Ravnborg This option is required by programs like DOSEMU to run 16-bit legacy 916506f1d07SSam Ravnborg code on X86 processors. It also may be needed by software like 917506f1d07SSam Ravnborg XFree86 to initialize some video cards via BIOS. Disabling this 918506f1d07SSam Ravnborg option saves about 6k. 919506f1d07SSam Ravnborg 920506f1d07SSam Ravnborgconfig TOSHIBA 921506f1d07SSam Ravnborg tristate "Toshiba Laptop support" 922506f1d07SSam Ravnborg depends on X86_32 923506f1d07SSam Ravnborg ---help--- 924506f1d07SSam Ravnborg This adds a driver to safely access the System Management Mode of 925506f1d07SSam Ravnborg the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 926506f1d07SSam Ravnborg not work on models with a Phoenix BIOS. The System Management Mode 927506f1d07SSam Ravnborg is used to set the BIOS and power saving options on Toshiba portables. 928506f1d07SSam Ravnborg 929506f1d07SSam Ravnborg For information on utilities to make use of this driver see the 930506f1d07SSam Ravnborg Toshiba Linux utilities web site at: 931506f1d07SSam Ravnborg <http://www.buzzard.org.uk/toshiba/>. 932506f1d07SSam Ravnborg 933506f1d07SSam Ravnborg Say Y if you intend to run this kernel on a Toshiba portable. 934506f1d07SSam Ravnborg Say N otherwise. 935506f1d07SSam Ravnborg 936506f1d07SSam Ravnborgconfig I8K 937506f1d07SSam Ravnborg tristate "Dell laptop support" 938949a9d70SJean Delvare select HWMON 939506f1d07SSam Ravnborg ---help--- 940506f1d07SSam Ravnborg This adds a driver to safely access the System Management Mode 941506f1d07SSam Ravnborg of the CPU on the Dell Inspiron 8000. The System Management Mode 942506f1d07SSam Ravnborg is used to read cpu temperature and cooling fan status and to 943506f1d07SSam Ravnborg control the fans on the I8K portables. 944506f1d07SSam Ravnborg 945506f1d07SSam Ravnborg This driver has been tested only on the Inspiron 8000 but it may 946506f1d07SSam Ravnborg also work with other Dell laptops. You can force loading on other 947506f1d07SSam Ravnborg models by passing the parameter `force=1' to the module. Use at 948506f1d07SSam Ravnborg your own risk. 949506f1d07SSam Ravnborg 950506f1d07SSam Ravnborg For information on utilities to make use of this driver see the 951506f1d07SSam Ravnborg I8K Linux utilities web site at: 952506f1d07SSam Ravnborg <http://people.debian.org/~dz/i8k/> 953506f1d07SSam Ravnborg 954506f1d07SSam Ravnborg Say Y if you intend to run this kernel on a Dell Inspiron 8000. 955506f1d07SSam Ravnborg Say N otherwise. 956506f1d07SSam Ravnborg 957506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS 9589ba16087SJan Beulich bool "Enable X86 board specific fixups for reboot" 9599ba16087SJan Beulich depends on X86_32 960506f1d07SSam Ravnborg ---help--- 961506f1d07SSam Ravnborg This enables chipset and/or board specific fixups to be done 962506f1d07SSam Ravnborg in order to get reboot to work correctly. This is only needed on 963506f1d07SSam Ravnborg some combinations of hardware and BIOS. The symptom, for which 964506f1d07SSam Ravnborg this config is intended, is when reboot ends with a stalled/hung 965506f1d07SSam Ravnborg system. 966506f1d07SSam Ravnborg 967506f1d07SSam Ravnborg Currently, the only fixup is for the Geode machines using 9685e3a77e9SFlorian Fainelli CS5530A and CS5536 chipsets and the RDC R-321x SoC. 969506f1d07SSam Ravnborg 970506f1d07SSam Ravnborg Say Y if you want to enable the fixup. Currently, it's safe to 971506f1d07SSam Ravnborg enable this option even if you don't need it. 972506f1d07SSam Ravnborg Say N otherwise. 973506f1d07SSam Ravnborg 974506f1d07SSam Ravnborgconfig MICROCODE 975e43f6e67SBorislav Petkov tristate "CPU microcode loading support" 97680030e3dSBorislav Petkov depends on CPU_SUP_AMD || CPU_SUP_INTEL 977506f1d07SSam Ravnborg select FW_LOADER 978506f1d07SSam Ravnborg ---help--- 979e43f6e67SBorislav Petkov 980506f1d07SSam Ravnborg If you say Y here, you will be able to update the microcode on 98180cc9f10SPeter Oruba certain Intel and AMD processors. The Intel support is for the 982e43f6e67SBorislav Petkov IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, 983e43f6e67SBorislav Petkov Xeon etc. The AMD support is for families 0x10 and later. You will 984e43f6e67SBorislav Petkov obviously need the actual microcode binary data itself which is not 985e43f6e67SBorislav Petkov shipped with the Linux kernel. 986506f1d07SSam Ravnborg 9878d86f390SPeter Oruba This option selects the general module only, you need to select 9888d86f390SPeter Oruba at least one vendor specific module as well. 989506f1d07SSam Ravnborg 990e43f6e67SBorislav Petkov To compile this driver as a module, choose M here: the module 991e43f6e67SBorislav Petkov will be called microcode. 992506f1d07SSam Ravnborg 9938d86f390SPeter Orubaconfig MICROCODE_INTEL 994e43f6e67SBorislav Petkov bool "Intel microcode loading support" 9958d86f390SPeter Oruba depends on MICROCODE 9968d86f390SPeter Oruba default MICROCODE 9978d86f390SPeter Oruba select FW_LOADER 9988f9ca475SIngo Molnar ---help--- 9998d86f390SPeter Oruba This options enables microcode patch loading support for Intel 10008d86f390SPeter Oruba processors. 10018d86f390SPeter Oruba 1002b8989db9SAlan For the current Intel microcode data package go to 1003b8989db9SAlan <https://downloadcenter.intel.com> and search for 1004b8989db9SAlan 'Linux Processor Microcode Data File'. 10058d86f390SPeter Oruba 100680cc9f10SPeter Orubaconfig MICROCODE_AMD 1007e43f6e67SBorislav Petkov bool "AMD microcode loading support" 100880cc9f10SPeter Oruba depends on MICROCODE 100980cc9f10SPeter Oruba select FW_LOADER 10108f9ca475SIngo Molnar ---help--- 101180cc9f10SPeter Oruba If you select this option, microcode patch loading support for AMD 101280cc9f10SPeter Oruba processors will be enabled. 101380cc9f10SPeter Oruba 1014506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE 10153c2362e6SHarvey Harrison def_bool y 1016506f1d07SSam Ravnborg depends on MICROCODE 1017506f1d07SSam Ravnborg 1018da76f64eSFenghua Yuconfig MICROCODE_INTEL_EARLY 1019757885e9SJacob Shin def_bool n 1020757885e9SJacob Shin 1021757885e9SJacob Shinconfig MICROCODE_AMD_EARLY 1022757885e9SJacob Shin def_bool n 1023757885e9SJacob Shin 1024757885e9SJacob Shinconfig MICROCODE_EARLY 1025da76f64eSFenghua Yu bool "Early load microcode" 10266b3389acSJacob Shin depends on MICROCODE=y && BLK_DEV_INITRD 1027757885e9SJacob Shin select MICROCODE_INTEL_EARLY if MICROCODE_INTEL 1028757885e9SJacob Shin select MICROCODE_AMD_EARLY if MICROCODE_AMD 1029da76f64eSFenghua Yu default y 1030da76f64eSFenghua Yu help 1031da76f64eSFenghua Yu This option provides functionality to read additional microcode data 1032da76f64eSFenghua Yu at the beginning of initrd image. The data tells kernel to load 1033da76f64eSFenghua Yu microcode to CPU's as early as possible. No functional change if no 1034da76f64eSFenghua Yu microcode data is glued to the initrd, therefore it's safe to say Y. 1035da76f64eSFenghua Yu 1036506f1d07SSam Ravnborgconfig X86_MSR 1037506f1d07SSam Ravnborg tristate "/dev/cpu/*/msr - Model-specific register support" 10388f9ca475SIngo Molnar ---help--- 1039506f1d07SSam Ravnborg This device gives privileged processes access to the x86 1040506f1d07SSam Ravnborg Model-Specific Registers (MSRs). It is a character device with 1041506f1d07SSam Ravnborg major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1042506f1d07SSam Ravnborg MSR accesses are directed to a specific CPU on multi-processor 1043506f1d07SSam Ravnborg systems. 1044506f1d07SSam Ravnborg 1045506f1d07SSam Ravnborgconfig X86_CPUID 1046506f1d07SSam Ravnborg tristate "/dev/cpu/*/cpuid - CPU information support" 10478f9ca475SIngo Molnar ---help--- 1048506f1d07SSam Ravnborg This device gives processes access to the x86 CPUID instruction to 1049506f1d07SSam Ravnborg be executed on a specific processor. It is a character device 1050506f1d07SSam Ravnborg with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1051506f1d07SSam Ravnborg /dev/cpu/31/cpuid. 1052506f1d07SSam Ravnborg 1053506f1d07SSam Ravnborgchoice 1054506f1d07SSam Ravnborg prompt "High Memory Support" 10556fc108a0SJan Beulich default HIGHMEM4G 1056506f1d07SSam Ravnborg depends on X86_32 1057506f1d07SSam Ravnborg 1058506f1d07SSam Ravnborgconfig NOHIGHMEM 1059506f1d07SSam Ravnborg bool "off" 1060506f1d07SSam Ravnborg ---help--- 1061506f1d07SSam Ravnborg Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1062506f1d07SSam Ravnborg However, the address space of 32-bit x86 processors is only 4 1063506f1d07SSam Ravnborg Gigabytes large. That means that, if you have a large amount of 1064506f1d07SSam Ravnborg physical memory, not all of it can be "permanently mapped" by the 1065506f1d07SSam Ravnborg kernel. The physical memory that's not permanently mapped is called 1066506f1d07SSam Ravnborg "high memory". 1067506f1d07SSam Ravnborg 1068506f1d07SSam Ravnborg If you are compiling a kernel which will never run on a machine with 1069506f1d07SSam Ravnborg more than 1 Gigabyte total physical RAM, answer "off" here (default 1070506f1d07SSam Ravnborg choice and suitable for most users). This will result in a "3GB/1GB" 1071506f1d07SSam Ravnborg split: 3GB are mapped so that each process sees a 3GB virtual memory 1072506f1d07SSam Ravnborg space and the remaining part of the 4GB virtual memory space is used 1073506f1d07SSam Ravnborg by the kernel to permanently map as much physical memory as 1074506f1d07SSam Ravnborg possible. 1075506f1d07SSam Ravnborg 1076506f1d07SSam Ravnborg If the machine has between 1 and 4 Gigabytes physical RAM, then 1077506f1d07SSam Ravnborg answer "4GB" here. 1078506f1d07SSam Ravnborg 1079506f1d07SSam Ravnborg If more than 4 Gigabytes is used then answer "64GB" here. This 1080506f1d07SSam Ravnborg selection turns Intel PAE (Physical Address Extension) mode on. 1081506f1d07SSam Ravnborg PAE implements 3-level paging on IA32 processors. PAE is fully 1082506f1d07SSam Ravnborg supported by Linux, PAE mode is implemented on all recent Intel 1083506f1d07SSam Ravnborg processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1084506f1d07SSam Ravnborg then the kernel will not boot on CPUs that don't support PAE! 1085506f1d07SSam Ravnborg 1086506f1d07SSam Ravnborg The actual amount of total physical memory will either be 1087506f1d07SSam Ravnborg auto detected or can be forced by using a kernel command line option 1088506f1d07SSam Ravnborg such as "mem=256M". (Try "man bootparam" or see the documentation of 1089506f1d07SSam Ravnborg your boot loader (lilo or loadlin) about how to pass options to the 1090506f1d07SSam Ravnborg kernel at boot time.) 1091506f1d07SSam Ravnborg 1092506f1d07SSam Ravnborg If unsure, say "off". 1093506f1d07SSam Ravnborg 1094506f1d07SSam Ravnborgconfig HIGHMEM4G 1095506f1d07SSam Ravnborg bool "4GB" 10968f9ca475SIngo Molnar ---help--- 1097506f1d07SSam Ravnborg Select this if you have a 32-bit processor and between 1 and 4 1098506f1d07SSam Ravnborg gigabytes of physical RAM. 1099506f1d07SSam Ravnborg 1100506f1d07SSam Ravnborgconfig HIGHMEM64G 1101506f1d07SSam Ravnborg bool "64GB" 1102eb068e78SH. Peter Anvin depends on !M486 1103506f1d07SSam Ravnborg select X86_PAE 11048f9ca475SIngo Molnar ---help--- 1105506f1d07SSam Ravnborg Select this if you have a 32-bit processor and more than 4 1106506f1d07SSam Ravnborg gigabytes of physical RAM. 1107506f1d07SSam Ravnborg 1108506f1d07SSam Ravnborgendchoice 1109506f1d07SSam Ravnborg 1110506f1d07SSam Ravnborgchoice 11116a108a14SDavid Rientjes prompt "Memory split" if EXPERT 1112506f1d07SSam Ravnborg default VMSPLIT_3G 1113506f1d07SSam Ravnborg depends on X86_32 11148f9ca475SIngo Molnar ---help--- 1115506f1d07SSam Ravnborg Select the desired split between kernel and user memory. 1116506f1d07SSam Ravnborg 1117506f1d07SSam Ravnborg If the address range available to the kernel is less than the 1118506f1d07SSam Ravnborg physical memory installed, the remaining memory will be available 1119506f1d07SSam Ravnborg as "high memory". Accessing high memory is a little more costly 1120506f1d07SSam Ravnborg than low memory, as it needs to be mapped into the kernel first. 1121506f1d07SSam Ravnborg Note that increasing the kernel address space limits the range 1122506f1d07SSam Ravnborg available to user programs, making the address space there 1123506f1d07SSam Ravnborg tighter. Selecting anything other than the default 3G/1G split 1124506f1d07SSam Ravnborg will also likely make your kernel incompatible with binary-only 1125506f1d07SSam Ravnborg kernel modules. 1126506f1d07SSam Ravnborg 1127506f1d07SSam Ravnborg If you are not absolutely sure what you are doing, leave this 1128506f1d07SSam Ravnborg option alone! 1129506f1d07SSam Ravnborg 1130506f1d07SSam Ravnborg config VMSPLIT_3G 1131506f1d07SSam Ravnborg bool "3G/1G user/kernel split" 1132506f1d07SSam Ravnborg config VMSPLIT_3G_OPT 1133506f1d07SSam Ravnborg depends on !X86_PAE 1134506f1d07SSam Ravnborg bool "3G/1G user/kernel split (for full 1G low memory)" 1135506f1d07SSam Ravnborg config VMSPLIT_2G 1136506f1d07SSam Ravnborg bool "2G/2G user/kernel split" 1137506f1d07SSam Ravnborg config VMSPLIT_2G_OPT 1138506f1d07SSam Ravnborg depends on !X86_PAE 1139506f1d07SSam Ravnborg bool "2G/2G user/kernel split (for full 2G low memory)" 1140506f1d07SSam Ravnborg config VMSPLIT_1G 1141506f1d07SSam Ravnborg bool "1G/3G user/kernel split" 1142506f1d07SSam Ravnborgendchoice 1143506f1d07SSam Ravnborg 1144506f1d07SSam Ravnborgconfig PAGE_OFFSET 1145506f1d07SSam Ravnborg hex 1146506f1d07SSam Ravnborg default 0xB0000000 if VMSPLIT_3G_OPT 1147506f1d07SSam Ravnborg default 0x80000000 if VMSPLIT_2G 1148506f1d07SSam Ravnborg default 0x78000000 if VMSPLIT_2G_OPT 1149506f1d07SSam Ravnborg default 0x40000000 if VMSPLIT_1G 1150506f1d07SSam Ravnborg default 0xC0000000 1151506f1d07SSam Ravnborg depends on X86_32 1152506f1d07SSam Ravnborg 1153506f1d07SSam Ravnborgconfig HIGHMEM 11543c2362e6SHarvey Harrison def_bool y 1155506f1d07SSam Ravnborg depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1156506f1d07SSam Ravnborg 1157506f1d07SSam Ravnborgconfig X86_PAE 11589ba16087SJan Beulich bool "PAE (Physical Address Extension) Support" 1159506f1d07SSam Ravnborg depends on X86_32 && !HIGHMEM4G 11608f9ca475SIngo Molnar ---help--- 1161506f1d07SSam Ravnborg PAE is required for NX support, and furthermore enables 1162506f1d07SSam Ravnborg larger swapspace support for non-overcommit purposes. It 1163506f1d07SSam Ravnborg has the cost of more pagetable lookup overhead, and also 1164506f1d07SSam Ravnborg consumes more pagetable space per process. 1165506f1d07SSam Ravnborg 1166600715dcSJeremy Fitzhardingeconfig ARCH_PHYS_ADDR_T_64BIT 11673120e25eSJan Beulich def_bool y 11683120e25eSJan Beulich depends on X86_64 || X86_PAE 1169600715dcSJeremy Fitzhardinge 117066f2b061SFUJITA Tomonoriconfig ARCH_DMA_ADDR_T_64BIT 11713120e25eSJan Beulich def_bool y 11723120e25eSJan Beulich depends on X86_64 || HIGHMEM64G 117366f2b061SFUJITA Tomonori 11749e899816SNick Pigginconfig DIRECT_GBPAGES 11756a108a14SDavid Rientjes bool "Enable 1GB pages for kernel pagetables" if EXPERT 11769e899816SNick Piggin default y 11779e899816SNick Piggin depends on X86_64 11788f9ca475SIngo Molnar ---help--- 11799e899816SNick Piggin Allow the kernel linear mapping to use 1GB pages on CPUs that 11809e899816SNick Piggin support it. This can improve the kernel's performance a tiny bit by 11819e899816SNick Piggin reducing TLB pressure. If in doubt, say "Y". 11829e899816SNick Piggin 1183506f1d07SSam Ravnborg# Common NUMA Features 1184506f1d07SSam Ravnborgconfig NUMA 1185fd51b2d7SKOSAKI Motohiro bool "Numa Memory Allocation and Scheduler Support" 1186506f1d07SSam Ravnborg depends on SMP 1187b5660ba7SH. Peter Anvin depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1188b5660ba7SH. Peter Anvin default y if X86_BIGSMP 11898f9ca475SIngo Molnar ---help--- 1190506f1d07SSam Ravnborg Enable NUMA (Non Uniform Memory Access) support. 1191fd51b2d7SKOSAKI Motohiro 1192506f1d07SSam Ravnborg The kernel will try to allocate memory used by a CPU on the 1193506f1d07SSam Ravnborg local memory controller of the CPU and add some more 1194506f1d07SSam Ravnborg NUMA awareness to the kernel. 1195506f1d07SSam Ravnborg 1196c280ea5eSIngo Molnar For 64-bit this is recommended if the system is Intel Core i7 1197fd51b2d7SKOSAKI Motohiro (or later), AMD Opteron, or EM64T NUMA. 1198fd51b2d7SKOSAKI Motohiro 1199b5660ba7SH. Peter Anvin For 32-bit this is only needed if you boot a 32-bit 12007cf6c945SDavid Rientjes kernel on a 64-bit NUMA platform. 1201fd51b2d7SKOSAKI Motohiro 1202fd51b2d7SKOSAKI Motohiro Otherwise, you should say N. 1203506f1d07SSam Ravnborg 1204eec1d4faSHans Rosenfeldconfig AMD_NUMA 12053c2362e6SHarvey Harrison def_bool y 12063c2362e6SHarvey Harrison prompt "Old style AMD Opteron NUMA detection" 12075da0ef9aSTejun Heo depends on X86_64 && NUMA && PCI 12088f9ca475SIngo Molnar ---help--- 1209eec1d4faSHans Rosenfeld Enable AMD NUMA node topology detection. You should say Y here if 1210eec1d4faSHans Rosenfeld you have a multi processor AMD system. This uses an old method to 1211eec1d4faSHans Rosenfeld read the NUMA configuration directly from the builtin Northbridge 1212eec1d4faSHans Rosenfeld of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1213eec1d4faSHans Rosenfeld which also takes priority if both are compiled in. 1214506f1d07SSam Ravnborg 1215506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA 12163c2362e6SHarvey Harrison def_bool y 12173c2362e6SHarvey Harrison prompt "ACPI NUMA detection" 1218506f1d07SSam Ravnborg depends on X86_64 && NUMA && ACPI && PCI 1219506f1d07SSam Ravnborg select ACPI_NUMA 12208f9ca475SIngo Molnar ---help--- 1221506f1d07SSam Ravnborg Enable ACPI SRAT based node topology detection. 1222506f1d07SSam Ravnborg 12236ec6e0d9SSuresh Siddha# Some NUMA nodes have memory ranges that span 12246ec6e0d9SSuresh Siddha# other nodes. Even though a pfn is valid and 12256ec6e0d9SSuresh Siddha# between a node's start and end pfns, it may not 12266ec6e0d9SSuresh Siddha# reside on that node. See memmap_init_zone() 12276ec6e0d9SSuresh Siddha# for details. 12286ec6e0d9SSuresh Siddhaconfig NODES_SPAN_OTHER_NODES 12296ec6e0d9SSuresh Siddha def_bool y 12306ec6e0d9SSuresh Siddha depends on X86_64_ACPI_NUMA 12316ec6e0d9SSuresh Siddha 1232506f1d07SSam Ravnborgconfig NUMA_EMU 1233506f1d07SSam Ravnborg bool "NUMA emulation" 12341b7e03efSTejun Heo depends on NUMA 12358f9ca475SIngo Molnar ---help--- 1236506f1d07SSam Ravnborg Enable NUMA emulation. A flat machine will be split 1237506f1d07SSam Ravnborg into virtual nodes when booted with "numa=fake=N", where N is the 1238506f1d07SSam Ravnborg number of nodes. This is only useful for debugging. 1239506f1d07SSam Ravnborg 1240506f1d07SSam Ravnborgconfig NODES_SHIFT 1241d25e26b6SLinus Torvalds int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 124251591e31SDavid Rientjes range 1 10 124351591e31SDavid Rientjes default "10" if MAXSMP 1244506f1d07SSam Ravnborg default "6" if X86_64 1245506f1d07SSam Ravnborg default "3" 1246506f1d07SSam Ravnborg depends on NEED_MULTIPLE_NODES 12478f9ca475SIngo Molnar ---help--- 12481184dc2fSMike Travis Specify the maximum number of NUMA Nodes available on the target 1249692105b8SMatt LaPlante system. Increases memory reserved to accommodate various tables. 1250506f1d07SSam Ravnborg 1251506f1d07SSam Ravnborgconfig ARCH_HAVE_MEMORY_PRESENT 12523c2362e6SHarvey Harrison def_bool y 1253506f1d07SSam Ravnborg depends on X86_32 && DISCONTIGMEM 1254506f1d07SSam Ravnborg 1255506f1d07SSam Ravnborgconfig NEED_NODE_MEMMAP_SIZE 12563c2362e6SHarvey Harrison def_bool y 1257506f1d07SSam Ravnborg depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1258506f1d07SSam Ravnborg 1259506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE 1260506f1d07SSam Ravnborg def_bool y 12613b16651fSTejun Heo depends on X86_32 && !NUMA 1262506f1d07SSam Ravnborg 1263506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_ENABLE 1264506f1d07SSam Ravnborg def_bool y 1265b263295dSChristoph Lameter depends on NUMA && X86_32 1266506f1d07SSam Ravnborg 1267506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_DEFAULT 1268506f1d07SSam Ravnborg def_bool y 1269b263295dSChristoph Lameter depends on NUMA && X86_32 1270b263295dSChristoph Lameter 1271506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE 1272506f1d07SSam Ravnborg def_bool y 12736ea30386SKees Cook depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1274506f1d07SSam Ravnborg select SPARSEMEM_STATIC if X86_32 1275506f1d07SSam Ravnborg select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1276506f1d07SSam Ravnborg 12773b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT 12783b16651fSTejun Heo def_bool y 12793b16651fSTejun Heo depends on X86_64 12803b16651fSTejun Heo 1281506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL 1282506f1d07SSam Ravnborg def_bool y 1283b263295dSChristoph Lameter depends on ARCH_SPARSEMEM_ENABLE 1284506f1d07SSam Ravnborg 1285506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE 1286a0842b70SToshi Kani bool "Enable sysfs memory/probe interface" 12873120e25eSJan Beulich depends on X86_64 && MEMORY_HOTPLUG 1288a0842b70SToshi Kani help 1289a0842b70SToshi Kani This option enables a sysfs memory/probe interface for testing. 1290a0842b70SToshi Kani See Documentation/memory-hotplug.txt for more information. 1291a0842b70SToshi Kani If you are unsure how to answer this question, answer N. 1292506f1d07SSam Ravnborg 12933b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT 12943b16651fSTejun Heo def_bool y 12953b16651fSTejun Heo depends on X86_64 && PROC_KCORE 12963b16651fSTejun Heo 1297a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE 1298a29815a3SAvi Kivity hex 1299a29815a3SAvi Kivity default 0 if X86_32 1300a29815a3SAvi Kivity default 0xdead000000000000 if X86_64 1301a29815a3SAvi Kivity 1302506f1d07SSam Ravnborgsource "mm/Kconfig" 1303506f1d07SSam Ravnborg 1304506f1d07SSam Ravnborgconfig HIGHPTE 1305506f1d07SSam Ravnborg bool "Allocate 3rd-level pagetables from highmem" 13066fc108a0SJan Beulich depends on HIGHMEM 13078f9ca475SIngo Molnar ---help--- 1308506f1d07SSam Ravnborg The VM uses one page table entry for each page of physical memory. 1309506f1d07SSam Ravnborg For systems with a lot of RAM, this can be wasteful of precious 1310506f1d07SSam Ravnborg low memory. Setting this option will put user-space page table 1311506f1d07SSam Ravnborg entries in high memory. 1312506f1d07SSam Ravnborg 13139f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION 13149f077871SJeremy Fitzhardinge bool "Check for low memory corruption" 13158f9ca475SIngo Molnar ---help--- 13169f077871SJeremy Fitzhardinge Periodically check for memory corruption in low memory, which 13179f077871SJeremy Fitzhardinge is suspected to be caused by BIOS. Even when enabled in the 13189f077871SJeremy Fitzhardinge configuration, it is disabled at runtime. Enable it by 13199f077871SJeremy Fitzhardinge setting "memory_corruption_check=1" on the kernel command 13209f077871SJeremy Fitzhardinge line. By default it scans the low 64k of memory every 60 13219f077871SJeremy Fitzhardinge seconds; see the memory_corruption_check_size and 13229f077871SJeremy Fitzhardinge memory_corruption_check_period parameters in 13239f077871SJeremy Fitzhardinge Documentation/kernel-parameters.txt to adjust this. 13249f077871SJeremy Fitzhardinge 13259f077871SJeremy Fitzhardinge When enabled with the default parameters, this option has 13269f077871SJeremy Fitzhardinge almost no overhead, as it reserves a relatively small amount 13279f077871SJeremy Fitzhardinge of memory and scans it infrequently. It both detects corruption 13289f077871SJeremy Fitzhardinge and prevents it from affecting the running system. 13299f077871SJeremy Fitzhardinge 13309f077871SJeremy Fitzhardinge It is, however, intended as a diagnostic tool; if repeatable 13319f077871SJeremy Fitzhardinge BIOS-originated corruption always affects the same memory, 13329f077871SJeremy Fitzhardinge you can use memmap= to prevent the kernel from using that 13339f077871SJeremy Fitzhardinge memory. 13349f077871SJeremy Fitzhardinge 1335c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1336c885df50SJeremy Fitzhardinge bool "Set the default setting of memory_corruption_check" 1337c885df50SJeremy Fitzhardinge depends on X86_CHECK_BIOS_CORRUPTION 1338c885df50SJeremy Fitzhardinge default y 13398f9ca475SIngo Molnar ---help--- 1340c885df50SJeremy Fitzhardinge Set whether the default state of memory_corruption_check is 1341c885df50SJeremy Fitzhardinge on or off. 1342c885df50SJeremy Fitzhardinge 13439ea77bdbSH. Peter Anvinconfig X86_RESERVE_LOW 1344d0cd7425SH. Peter Anvin int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1345d0cd7425SH. Peter Anvin default 64 1346d0cd7425SH. Peter Anvin range 4 640 13478f9ca475SIngo Molnar ---help--- 1348d0cd7425SH. Peter Anvin Specify the amount of low memory to reserve for the BIOS. 1349fc381519SIngo Molnar 1350d0cd7425SH. Peter Anvin The first page contains BIOS data structures that the kernel 1351d0cd7425SH. Peter Anvin must not use, so that page must always be reserved. 1352fc381519SIngo Molnar 1353d0cd7425SH. Peter Anvin By default we reserve the first 64K of physical RAM, as a 1354d0cd7425SH. Peter Anvin number of BIOSes are known to corrupt that memory range 1355d0cd7425SH. Peter Anvin during events such as suspend/resume or monitor cable 1356d0cd7425SH. Peter Anvin insertion, so it must not be used by the kernel. 1357fc381519SIngo Molnar 1358d0cd7425SH. Peter Anvin You can set this to 4 if you are absolutely sure that you 1359d0cd7425SH. Peter Anvin trust the BIOS to get all its memory reservations and usages 1360d0cd7425SH. Peter Anvin right. If you know your BIOS have problems beyond the 1361d0cd7425SH. Peter Anvin default 64K area, you can set this to 640 to avoid using the 1362d0cd7425SH. Peter Anvin entire low memory range. 1363d0cd7425SH. Peter Anvin 1364d0cd7425SH. Peter Anvin If you have doubts about the BIOS (e.g. suspend/resume does 1365d0cd7425SH. Peter Anvin not work or there's kernel crashes after certain hardware 1366d0cd7425SH. Peter Anvin hotplug events) then you might want to enable 1367d0cd7425SH. Peter Anvin X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1368d0cd7425SH. Peter Anvin typical corruption patterns. 1369d0cd7425SH. Peter Anvin 1370d0cd7425SH. Peter Anvin Leave this to the default value of 64 if you are unsure. 1371fc381519SIngo Molnar 1372506f1d07SSam Ravnborgconfig MATH_EMULATION 1373506f1d07SSam Ravnborg bool 1374506f1d07SSam Ravnborg prompt "Math emulation" if X86_32 1375506f1d07SSam Ravnborg ---help--- 1376506f1d07SSam Ravnborg Linux can emulate a math coprocessor (used for floating point 1377506f1d07SSam Ravnborg operations) if you don't have one. 486DX and Pentium processors have 1378506f1d07SSam Ravnborg a math coprocessor built in, 486SX and 386 do not, unless you added 1379506f1d07SSam Ravnborg a 487DX or 387, respectively. (The messages during boot time can 1380506f1d07SSam Ravnborg give you some hints here ["man dmesg"].) Everyone needs either a 1381506f1d07SSam Ravnborg coprocessor or this emulation. 1382506f1d07SSam Ravnborg 1383506f1d07SSam Ravnborg If you don't have a math coprocessor, you need to say Y here; if you 1384506f1d07SSam Ravnborg say Y here even though you have a coprocessor, the coprocessor will 1385506f1d07SSam Ravnborg be used nevertheless. (This behavior can be changed with the kernel 1386506f1d07SSam Ravnborg command line option "no387", which comes handy if your coprocessor 1387506f1d07SSam Ravnborg is broken. Try "man bootparam" or see the documentation of your boot 1388506f1d07SSam Ravnborg loader (lilo or loadlin) about how to pass options to the kernel at 1389506f1d07SSam Ravnborg boot time.) This means that it is a good idea to say Y here if you 1390506f1d07SSam Ravnborg intend to use this kernel on different machines. 1391506f1d07SSam Ravnborg 1392506f1d07SSam Ravnborg More information about the internals of the Linux math coprocessor 1393506f1d07SSam Ravnborg emulation can be found in <file:arch/x86/math-emu/README>. 1394506f1d07SSam Ravnborg 1395506f1d07SSam Ravnborg If you are not sure, say Y; apart from resulting in a 66 KB bigger 1396506f1d07SSam Ravnborg kernel, it won't hurt. 1397506f1d07SSam Ravnborg 1398506f1d07SSam Ravnborgconfig MTRR 13996fc108a0SJan Beulich def_bool y 14006a108a14SDavid Rientjes prompt "MTRR (Memory Type Range Register) support" if EXPERT 1401506f1d07SSam Ravnborg ---help--- 1402506f1d07SSam Ravnborg On Intel P6 family processors (Pentium Pro, Pentium II and later) 1403506f1d07SSam Ravnborg the Memory Type Range Registers (MTRRs) may be used to control 1404506f1d07SSam Ravnborg processor access to memory ranges. This is most useful if you have 1405506f1d07SSam Ravnborg a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1406506f1d07SSam Ravnborg allows bus write transfers to be combined into a larger transfer 1407506f1d07SSam Ravnborg before bursting over the PCI/AGP bus. This can increase performance 1408506f1d07SSam Ravnborg of image write operations 2.5 times or more. Saying Y here creates a 1409506f1d07SSam Ravnborg /proc/mtrr file which may be used to manipulate your processor's 1410506f1d07SSam Ravnborg MTRRs. Typically the X server should use this. 1411506f1d07SSam Ravnborg 1412506f1d07SSam Ravnborg This code has a reasonably generic interface so that similar 1413506f1d07SSam Ravnborg control registers on other processors can be easily supported 1414506f1d07SSam Ravnborg as well: 1415506f1d07SSam Ravnborg 1416506f1d07SSam Ravnborg The Cyrix 6x86, 6x86MX and M II processors have Address Range 1417506f1d07SSam Ravnborg Registers (ARRs) which provide a similar functionality to MTRRs. For 1418506f1d07SSam Ravnborg these, the ARRs are used to emulate the MTRRs. 1419506f1d07SSam Ravnborg The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1420506f1d07SSam Ravnborg MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1421506f1d07SSam Ravnborg write-combining. All of these processors are supported by this code 1422506f1d07SSam Ravnborg and it makes sense to say Y here if you have one of them. 1423506f1d07SSam Ravnborg 1424506f1d07SSam Ravnborg Saying Y here also fixes a problem with buggy SMP BIOSes which only 1425506f1d07SSam Ravnborg set the MTRRs for the boot CPU and not for the secondary CPUs. This 1426506f1d07SSam Ravnborg can lead to all sorts of problems, so it's good to say Y here. 1427506f1d07SSam Ravnborg 1428506f1d07SSam Ravnborg You can safely say Y even if your machine doesn't have MTRRs, you'll 1429506f1d07SSam Ravnborg just add about 9 KB to your kernel. 1430506f1d07SSam Ravnborg 14317225e751SRandy Dunlap See <file:Documentation/x86/mtrr.txt> for more information. 1432506f1d07SSam Ravnborg 143395ffa243SYinghai Luconfig MTRR_SANITIZER 14342ffb3501SYinghai Lu def_bool y 143595ffa243SYinghai Lu prompt "MTRR cleanup support" 143695ffa243SYinghai Lu depends on MTRR 14378f9ca475SIngo Molnar ---help--- 1438aba3728cSThomas Gleixner Convert MTRR layout from continuous to discrete, so X drivers can 1439aba3728cSThomas Gleixner add writeback entries. 144095ffa243SYinghai Lu 1441aba3728cSThomas Gleixner Can be disabled with disable_mtrr_cleanup on the kernel command line. 1442692105b8SMatt LaPlante The largest mtrr entry size for a continuous block can be set with 1443aba3728cSThomas Gleixner mtrr_chunk_size. 144495ffa243SYinghai Lu 14452ffb3501SYinghai Lu If unsure, say Y. 144695ffa243SYinghai Lu 144795ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT 1448f5098d62SYinghai Lu int "MTRR cleanup enable value (0-1)" 1449f5098d62SYinghai Lu range 0 1 1450f5098d62SYinghai Lu default "0" 145195ffa243SYinghai Lu depends on MTRR_SANITIZER 14528f9ca475SIngo Molnar ---help--- 1453f5098d62SYinghai Lu Enable mtrr cleanup default value 145495ffa243SYinghai Lu 145512031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 145612031a62SYinghai Lu int "MTRR cleanup spare reg num (0-7)" 145712031a62SYinghai Lu range 0 7 145812031a62SYinghai Lu default "1" 145912031a62SYinghai Lu depends on MTRR_SANITIZER 14608f9ca475SIngo Molnar ---help--- 146112031a62SYinghai Lu mtrr cleanup spare entries default, it can be changed via 1462aba3728cSThomas Gleixner mtrr_spare_reg_nr=N on the kernel command line. 146312031a62SYinghai Lu 14642e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT 14656fc108a0SJan Beulich def_bool y 14666a108a14SDavid Rientjes prompt "x86 PAT support" if EXPERT 14672a8a2719SIngo Molnar depends on MTRR 14688f9ca475SIngo Molnar ---help--- 14692e5d9c85Svenkatesh.pallipadi@intel.com Use PAT attributes to setup page level cache control. 1470042b78e4SVenki Pallipadi 14712e5d9c85Svenkatesh.pallipadi@intel.com PATs are the modern equivalents of MTRRs and are much more 14722e5d9c85Svenkatesh.pallipadi@intel.com flexible than MTRRs. 14732e5d9c85Svenkatesh.pallipadi@intel.com 14742e5d9c85Svenkatesh.pallipadi@intel.com Say N here if you see bootup problems (boot crash, boot hang, 1475042b78e4SVenki Pallipadi spontaneous reboots) or a non-working video driver. 14762e5d9c85Svenkatesh.pallipadi@intel.com 14772e5d9c85Svenkatesh.pallipadi@intel.com If unsure, say Y. 14782e5d9c85Svenkatesh.pallipadi@intel.com 147946cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED 148046cf98cdSVenkatesh Pallipadi def_bool y 148146cf98cdSVenkatesh Pallipadi depends on X86_PAT 148246cf98cdSVenkatesh Pallipadi 1483628c6246SH. Peter Anvinconfig ARCH_RANDOM 1484628c6246SH. Peter Anvin def_bool y 1485628c6246SH. Peter Anvin prompt "x86 architectural random number generator" if EXPERT 1486628c6246SH. Peter Anvin ---help--- 1487628c6246SH. Peter Anvin Enable the x86 architectural RDRAND instruction 1488628c6246SH. Peter Anvin (Intel Bull Mountain technology) to generate random numbers. 1489628c6246SH. Peter Anvin If supported, this is a high bandwidth, cryptographically 1490628c6246SH. Peter Anvin secure hardware random number generator. 1491628c6246SH. Peter Anvin 149251ae4a2dSH. Peter Anvinconfig X86_SMAP 149351ae4a2dSH. Peter Anvin def_bool y 149451ae4a2dSH. Peter Anvin prompt "Supervisor Mode Access Prevention" if EXPERT 149551ae4a2dSH. Peter Anvin ---help--- 149651ae4a2dSH. Peter Anvin Supervisor Mode Access Prevention (SMAP) is a security 149751ae4a2dSH. Peter Anvin feature in newer Intel processors. There is a small 149851ae4a2dSH. Peter Anvin performance cost if this enabled and turned on; there is 149951ae4a2dSH. Peter Anvin also a small increase in the kernel size if this is enabled. 150051ae4a2dSH. Peter Anvin 150151ae4a2dSH. Peter Anvin If unsure, say Y. 150251ae4a2dSH. Peter Anvin 1503506f1d07SSam Ravnborgconfig EFI 15049ba16087SJan Beulich bool "EFI runtime service support" 15055b83683fSHuang, Ying depends on ACPI 1506f6ce5002SSergey Vlasov select UCS2_STRING 1507506f1d07SSam Ravnborg ---help--- 15088b2cb7a8SHuang, Ying This enables the kernel to use EFI runtime services that are 1509506f1d07SSam Ravnborg available (such as the EFI variable services). 1510506f1d07SSam Ravnborg 15118b2cb7a8SHuang, Ying This option is only useful on systems that have EFI firmware. 15128b2cb7a8SHuang, Ying In addition, you should use the latest ELILO loader available 15138b2cb7a8SHuang, Ying at <http://elilo.sourceforge.net> in order to take advantage 15148b2cb7a8SHuang, Ying of EFI runtime services. However, even with this option, the 15158b2cb7a8SHuang, Ying resultant kernel should continue to boot on existing non-EFI 15168b2cb7a8SHuang, Ying platforms. 1517506f1d07SSam Ravnborg 1518291f3632SMatt Flemingconfig EFI_STUB 1519291f3632SMatt Fleming bool "EFI stub support" 1520291f3632SMatt Fleming depends on EFI 1521291f3632SMatt Fleming ---help--- 1522291f3632SMatt Fleming This kernel feature allows a bzImage to be loaded directly 1523291f3632SMatt Fleming by EFI firmware without the use of a bootloader. 1524291f3632SMatt Fleming 15254172fe2fSRoy Franz See Documentation/efi-stub.txt for more information. 15260c759662SMatt Fleming 15277d453eeeSMatt Flemingconfig EFI_MIXED 15287d453eeeSMatt Fleming bool "EFI mixed-mode support" 15297d453eeeSMatt Fleming depends on EFI_STUB && X86_64 15307d453eeeSMatt Fleming ---help--- 15317d453eeeSMatt Fleming Enabling this feature allows a 64-bit kernel to be booted 15327d453eeeSMatt Fleming on a 32-bit firmware, provided that your CPU supports 64-bit 15337d453eeeSMatt Fleming mode. 15347d453eeeSMatt Fleming 15357d453eeeSMatt Fleming Note that it is not possible to boot a mixed-mode enabled 15367d453eeeSMatt Fleming kernel via the EFI boot stub - a bootloader that supports 15377d453eeeSMatt Fleming the EFI handover protocol must be used. 15387d453eeeSMatt Fleming 15397d453eeeSMatt Fleming If unsure, say N. 15407d453eeeSMatt Fleming 1541506f1d07SSam Ravnborgconfig SECCOMP 15423c2362e6SHarvey Harrison def_bool y 15433c2362e6SHarvey Harrison prompt "Enable seccomp to safely compute untrusted bytecode" 15448f9ca475SIngo Molnar ---help--- 1545506f1d07SSam Ravnborg This kernel feature is useful for number crunching applications 1546506f1d07SSam Ravnborg that may need to compute untrusted bytecode during their 1547506f1d07SSam Ravnborg execution. By using pipes or other transports made available to 1548506f1d07SSam Ravnborg the process as file descriptors supporting the read/write 1549506f1d07SSam Ravnborg syscalls, it's possible to isolate those applications in 1550506f1d07SSam Ravnborg their own address space using seccomp. Once seccomp is 15519c0bbee8SAlexey Dobriyan enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1552506f1d07SSam Ravnborg and the task is only allowed to execute a few safe syscalls 1553506f1d07SSam Ravnborg defined by each seccomp mode. 1554506f1d07SSam Ravnborg 1555506f1d07SSam Ravnborg If unsure, say Y. Only embedded should say N here. 1556506f1d07SSam Ravnborg 1557506f1d07SSam Ravnborgsource kernel/Kconfig.hz 1558506f1d07SSam Ravnborg 1559506f1d07SSam Ravnborgconfig KEXEC 1560506f1d07SSam Ravnborg bool "kexec system call" 15618f9ca475SIngo Molnar ---help--- 1562506f1d07SSam Ravnborg kexec is a system call that implements the ability to shutdown your 1563506f1d07SSam Ravnborg current kernel, and to start another kernel. It is like a reboot 1564506f1d07SSam Ravnborg but it is independent of the system firmware. And like a reboot 1565506f1d07SSam Ravnborg you can start any kernel with it, not just Linux. 1566506f1d07SSam Ravnborg 1567506f1d07SSam Ravnborg The name comes from the similarity to the exec system call. 1568506f1d07SSam Ravnborg 1569506f1d07SSam Ravnborg It is an ongoing process to be certain the hardware in a machine 1570506f1d07SSam Ravnborg is properly shutdown, so do not be surprised if this code does not 1571bf220695SGeert Uytterhoeven initially work for you. As of this writing the exact hardware 1572bf220695SGeert Uytterhoeven interface is strongly in flux, so no good recommendation can be 1573bf220695SGeert Uytterhoeven made. 1574506f1d07SSam Ravnborg 1575506f1d07SSam Ravnborgconfig CRASH_DUMP 157604b69447SPavel Machek bool "kernel crash dumps" 1577506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 15788f9ca475SIngo Molnar ---help--- 1579506f1d07SSam Ravnborg Generate crash dump after being started by kexec. 1580506f1d07SSam Ravnborg This should be normally only set in special crash dump kernels 1581506f1d07SSam Ravnborg which are loaded in the main kernel with kexec-tools into 1582506f1d07SSam Ravnborg a specially reserved region and then later executed after 1583506f1d07SSam Ravnborg a crash by kdump/kexec. The crash dump kernel must be compiled 1584506f1d07SSam Ravnborg to a memory address not used by the main kernel or BIOS using 1585506f1d07SSam Ravnborg PHYSICAL_START, or it must be built as a relocatable image 1586506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y). 1587506f1d07SSam Ravnborg For more details see Documentation/kdump/kdump.txt 1588506f1d07SSam Ravnborg 15893ab83521SHuang Yingconfig KEXEC_JUMP 15906ea30386SKees Cook bool "kexec jump" 1591fee7b0d8SHuang Ying depends on KEXEC && HIBERNATION 15928f9ca475SIngo Molnar ---help--- 159389081d17SHuang Ying Jump between original kernel and kexeced kernel and invoke 159489081d17SHuang Ying code in physical address mode via KEXEC 15953ab83521SHuang Ying 1596506f1d07SSam Ravnborgconfig PHYSICAL_START 15976a108a14SDavid Rientjes hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1598ceefccc9SH. Peter Anvin default "0x1000000" 15998f9ca475SIngo Molnar ---help--- 1600506f1d07SSam Ravnborg This gives the physical address where the kernel is loaded. 1601506f1d07SSam Ravnborg 1602506f1d07SSam Ravnborg If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1603506f1d07SSam Ravnborg bzImage will decompress itself to above physical address and 1604506f1d07SSam Ravnborg run from there. Otherwise, bzImage will run from the address where 1605506f1d07SSam Ravnborg it has been loaded by the boot loader and will ignore above physical 1606506f1d07SSam Ravnborg address. 1607506f1d07SSam Ravnborg 1608506f1d07SSam Ravnborg In normal kdump cases one does not have to set/change this option 1609506f1d07SSam Ravnborg as now bzImage can be compiled as a completely relocatable image 1610506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1611506f1d07SSam Ravnborg address. This option is mainly useful for the folks who don't want 1612506f1d07SSam Ravnborg to use a bzImage for capturing the crash dump and want to use a 1613506f1d07SSam Ravnborg vmlinux instead. vmlinux is not relocatable hence a kernel needs 1614506f1d07SSam Ravnborg to be specifically compiled to run from a specific memory area 1615506f1d07SSam Ravnborg (normally a reserved region) and this option comes handy. 1616506f1d07SSam Ravnborg 1617ceefccc9SH. Peter Anvin So if you are using bzImage for capturing the crash dump, 1618ceefccc9SH. Peter Anvin leave the value here unchanged to 0x1000000 and set 1619ceefccc9SH. Peter Anvin CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1620ceefccc9SH. Peter Anvin for capturing the crash dump change this value to start of 1621ceefccc9SH. Peter Anvin the reserved region. In other words, it can be set based on 1622ceefccc9SH. Peter Anvin the "X" value as specified in the "crashkernel=YM@XM" 1623ceefccc9SH. Peter Anvin command line boot parameter passed to the panic-ed 1624ceefccc9SH. Peter Anvin kernel. Please take a look at Documentation/kdump/kdump.txt 1625ceefccc9SH. Peter Anvin for more details about crash dumps. 1626506f1d07SSam Ravnborg 1627506f1d07SSam Ravnborg Usage of bzImage for capturing the crash dump is recommended as 1628506f1d07SSam Ravnborg one does not have to build two kernels. Same kernel can be used 1629506f1d07SSam Ravnborg as production kernel and capture kernel. Above option should have 1630506f1d07SSam Ravnborg gone away after relocatable bzImage support is introduced. But it 1631506f1d07SSam Ravnborg is present because there are users out there who continue to use 1632506f1d07SSam Ravnborg vmlinux for dump capture. This option should go away down the 1633506f1d07SSam Ravnborg line. 1634506f1d07SSam Ravnborg 1635506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 1636506f1d07SSam Ravnborg 1637506f1d07SSam Ravnborgconfig RELOCATABLE 163826717808SH. Peter Anvin bool "Build a relocatable kernel" 163926717808SH. Peter Anvin default y 16408f9ca475SIngo Molnar ---help--- 1641506f1d07SSam Ravnborg This builds a kernel image that retains relocation information 1642506f1d07SSam Ravnborg so it can be loaded someplace besides the default 1MB. 1643506f1d07SSam Ravnborg The relocations tend to make the kernel binary about 10% larger, 1644506f1d07SSam Ravnborg but are discarded at runtime. 1645506f1d07SSam Ravnborg 1646506f1d07SSam Ravnborg One use is for the kexec on panic case where the recovery kernel 1647506f1d07SSam Ravnborg must live at a different physical address than the primary 1648506f1d07SSam Ravnborg kernel. 1649506f1d07SSam Ravnborg 1650506f1d07SSam Ravnborg Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1651506f1d07SSam Ravnborg it has been loaded at and the compile time physical address 16528ab3820fSKees Cook (CONFIG_PHYSICAL_START) is used as the minimum location. 1653506f1d07SSam Ravnborg 16548ab3820fSKees Cookconfig RANDOMIZE_BASE 16558ab3820fSKees Cook bool "Randomize the address of the kernel image" 16568ab3820fSKees Cook depends on RELOCATABLE 16578ab3820fSKees Cook depends on !HIBERNATION 16588ab3820fSKees Cook default n 16598ab3820fSKees Cook ---help--- 16608ab3820fSKees Cook Randomizes the physical and virtual address at which the 16618ab3820fSKees Cook kernel image is decompressed, as a security feature that 16628ab3820fSKees Cook deters exploit attempts relying on knowledge of the location 16638ab3820fSKees Cook of kernel internals. 16648ab3820fSKees Cook 1665a653f356SKees Cook Entropy is generated using the RDRAND instruction if it is 1666a653f356SKees Cook supported. If RDTSC is supported, it is used as well. If 1667a653f356SKees Cook neither RDRAND nor RDTSC are supported, then randomness is 1668a653f356SKees Cook read from the i8254 timer. 16698ab3820fSKees Cook 16708ab3820fSKees Cook The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET, 1671a653f356SKees Cook and aligned according to PHYSICAL_ALIGN. Since the kernel is 1672a653f356SKees Cook built using 2GiB addressing, and PHYSICAL_ALGIN must be at a 1673a653f356SKees Cook minimum of 2MiB, only 10 bits of entropy is theoretically 1674a653f356SKees Cook possible. At best, due to page table layouts, 64-bit can use 1675a653f356SKees Cook 9 bits of entropy and 32-bit uses 8 bits. 16768ab3820fSKees Cook 1677da2b6fb9SKees Cook If unsure, say N. 1678da2b6fb9SKees Cook 16798ab3820fSKees Cookconfig RANDOMIZE_BASE_MAX_OFFSET 1680da2b6fb9SKees Cook hex "Maximum kASLR offset allowed" if EXPERT 16818ab3820fSKees Cook depends on RANDOMIZE_BASE 16826145cfe3SKees Cook range 0x0 0x20000000 if X86_32 16836145cfe3SKees Cook default "0x20000000" if X86_32 16846145cfe3SKees Cook range 0x0 0x40000000 if X86_64 16856145cfe3SKees Cook default "0x40000000" if X86_64 16868ab3820fSKees Cook ---help--- 1687da2b6fb9SKees Cook The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical 1688da2b6fb9SKees Cook memory is used to determine the maximal offset in bytes that will 1689da2b6fb9SKees Cook be applied to the kernel when kernel Address Space Layout 1690da2b6fb9SKees Cook Randomization (kASLR) is active. This must be a multiple of 1691da2b6fb9SKees Cook PHYSICAL_ALIGN. 16926145cfe3SKees Cook 1693da2b6fb9SKees Cook On 32-bit this is limited to 512MiB by page table layouts. The 1694da2b6fb9SKees Cook default is 512MiB. 16956145cfe3SKees Cook 16966145cfe3SKees Cook On 64-bit this is limited by how the kernel fixmap page table is 1697da2b6fb9SKees Cook positioned, so this cannot be larger than 1GiB currently. Without 1698da2b6fb9SKees Cook RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel 1699da2b6fb9SKees Cook and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the 1700da2b6fb9SKees Cook modules area will shrink to compensate, up to the current maximum 1701da2b6fb9SKees Cook 1GiB to 1GiB split. The default is 1GiB. 1702da2b6fb9SKees Cook 1703da2b6fb9SKees Cook If unsure, leave at the default value. 17048ab3820fSKees Cook 17058ab3820fSKees Cook# Relocation on x86 needs some additional build support 1706845adf72SH. Peter Anvinconfig X86_NEED_RELOCS 1707845adf72SH. Peter Anvin def_bool y 17088ab3820fSKees Cook depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 1709845adf72SH. Peter Anvin 1710506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN 1711a0215061SKees Cook hex "Alignment value to which kernel should be aligned" 17128ab3820fSKees Cook default "0x200000" 1713a0215061SKees Cook range 0x2000 0x1000000 if X86_32 1714a0215061SKees Cook range 0x200000 0x1000000 if X86_64 17158f9ca475SIngo Molnar ---help--- 1716506f1d07SSam Ravnborg This value puts the alignment restrictions on physical address 1717506f1d07SSam Ravnborg where kernel is loaded and run from. Kernel is compiled for an 1718506f1d07SSam Ravnborg address which meets above alignment restriction. 1719506f1d07SSam Ravnborg 1720506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 1721506f1d07SSam Ravnborg CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1722506f1d07SSam Ravnborg address aligned to above value and run from there. 1723506f1d07SSam Ravnborg 1724506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 1725506f1d07SSam Ravnborg CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1726506f1d07SSam Ravnborg load address and decompress itself to the address it has been 1727506f1d07SSam Ravnborg compiled for and run from there. The address for which kernel is 1728506f1d07SSam Ravnborg compiled already meets above alignment restrictions. Hence the 1729506f1d07SSam Ravnborg end result is that kernel runs from a physical address meeting 1730506f1d07SSam Ravnborg above alignment restrictions. 1731506f1d07SSam Ravnborg 1732a0215061SKees Cook On 32-bit this value must be a multiple of 0x2000. On 64-bit 1733a0215061SKees Cook this value must be a multiple of 0x200000. 1734a0215061SKees Cook 1735506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 1736506f1d07SSam Ravnborg 1737506f1d07SSam Ravnborgconfig HOTPLUG_CPU 17387c13e6a3SDimitri Sivanich bool "Support for hot-pluggable CPUs" 173940b31360SStephen Rothwell depends on SMP 1740506f1d07SSam Ravnborg ---help--- 17417c13e6a3SDimitri Sivanich Say Y here to allow turning CPUs off and on. CPUs can be 17427c13e6a3SDimitri Sivanich controlled through /sys/devices/system/cpu. 17437c13e6a3SDimitri Sivanich ( Note: power management support will enable this option 17447c13e6a3SDimitri Sivanich automatically on SMP systems. ) 17457c13e6a3SDimitri Sivanich Say N if you want to disable CPU hotplug. 1746506f1d07SSam Ravnborg 174780aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0 174880aa1dffSFenghua Yu bool "Set default setting of cpu0_hotpluggable" 174980aa1dffSFenghua Yu default n 17502c922cd0SKees Cook depends on HOTPLUG_CPU 175180aa1dffSFenghua Yu ---help--- 175280aa1dffSFenghua Yu Set whether default state of cpu0_hotpluggable is on or off. 175380aa1dffSFenghua Yu 175480aa1dffSFenghua Yu Say Y here to enable CPU0 hotplug by default. If this switch 175580aa1dffSFenghua Yu is turned on, there is no need to give cpu0_hotplug kernel 175680aa1dffSFenghua Yu parameter and the CPU0 hotplug feature is enabled by default. 175780aa1dffSFenghua Yu 175880aa1dffSFenghua Yu Please note: there are two known CPU0 dependencies if you want 175980aa1dffSFenghua Yu to enable the CPU0 hotplug feature either by this switch or by 176080aa1dffSFenghua Yu cpu0_hotplug kernel parameter. 176180aa1dffSFenghua Yu 176280aa1dffSFenghua Yu First, resume from hibernate or suspend always starts from CPU0. 176380aa1dffSFenghua Yu So hibernate and suspend are prevented if CPU0 is offline. 176480aa1dffSFenghua Yu 176580aa1dffSFenghua Yu Second dependency is PIC interrupts always go to CPU0. CPU0 can not 176680aa1dffSFenghua Yu offline if any interrupt can not migrate out of CPU0. There may 176780aa1dffSFenghua Yu be other CPU0 dependencies. 176880aa1dffSFenghua Yu 176980aa1dffSFenghua Yu Please make sure the dependencies are under your control before 177080aa1dffSFenghua Yu you enable this feature. 177180aa1dffSFenghua Yu 177280aa1dffSFenghua Yu Say N if you don't want to enable CPU0 hotplug feature by default. 177380aa1dffSFenghua Yu You still can enable the CPU0 hotplug feature at boot by kernel 177480aa1dffSFenghua Yu parameter cpu0_hotplug. 177580aa1dffSFenghua Yu 1776a71c8bc5SFenghua Yuconfig DEBUG_HOTPLUG_CPU0 1777a71c8bc5SFenghua Yu def_bool n 1778a71c8bc5SFenghua Yu prompt "Debug CPU0 hotplug" 17792c922cd0SKees Cook depends on HOTPLUG_CPU 1780a71c8bc5SFenghua Yu ---help--- 1781a71c8bc5SFenghua Yu Enabling this option offlines CPU0 (if CPU0 can be offlined) as 1782a71c8bc5SFenghua Yu soon as possible and boots up userspace with CPU0 offlined. User 1783a71c8bc5SFenghua Yu can online CPU0 back after boot time. 1784a71c8bc5SFenghua Yu 1785a71c8bc5SFenghua Yu To debug CPU0 hotplug, you need to enable CPU0 offline/online 1786a71c8bc5SFenghua Yu feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 1787a71c8bc5SFenghua Yu compilation or giving cpu0_hotplug kernel parameter at boot. 1788a71c8bc5SFenghua Yu 1789a71c8bc5SFenghua Yu If unsure, say N. 1790a71c8bc5SFenghua Yu 1791506f1d07SSam Ravnborgconfig COMPAT_VDSO 1792b0b49f26SAndy Lutomirski def_bool n 1793b0b49f26SAndy Lutomirski prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 1794af65d648SRoland McGrath depends on X86_32 || IA32_EMULATION 17958f9ca475SIngo Molnar ---help--- 1796b0b49f26SAndy Lutomirski Certain buggy versions of glibc will crash if they are 1797b0b49f26SAndy Lutomirski presented with a 32-bit vDSO that is not mapped at the address 1798b0b49f26SAndy Lutomirski indicated in its segment table. 1799e84446deSRandy Dunlap 1800b0b49f26SAndy Lutomirski The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 1801b0b49f26SAndy Lutomirski and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 1802b0b49f26SAndy Lutomirski 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 1803b0b49f26SAndy Lutomirski the only released version with the bug, but OpenSUSE 9 1804b0b49f26SAndy Lutomirski contains a buggy "glibc 2.3.2". 1805506f1d07SSam Ravnborg 1806b0b49f26SAndy Lutomirski The symptom of the bug is that everything crashes on startup, saying: 1807b0b49f26SAndy Lutomirski dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 1808b0b49f26SAndy Lutomirski 1809b0b49f26SAndy Lutomirski Saying Y here changes the default value of the vdso32 boot 1810b0b49f26SAndy Lutomirski option from 1 to 0, which turns off the 32-bit vDSO entirely. 1811b0b49f26SAndy Lutomirski This works around the glibc bug but hurts performance. 1812b0b49f26SAndy Lutomirski 1813b0b49f26SAndy Lutomirski If unsure, say N: if you are compiling your own kernel, you 1814b0b49f26SAndy Lutomirski are unlikely to be using a buggy version of glibc. 1815506f1d07SSam Ravnborg 1816516cbf37STim Birdconfig CMDLINE_BOOL 1817516cbf37STim Bird bool "Built-in kernel command line" 18188f9ca475SIngo Molnar ---help--- 1819516cbf37STim Bird Allow for specifying boot arguments to the kernel at 1820516cbf37STim Bird build time. On some systems (e.g. embedded ones), it is 1821516cbf37STim Bird necessary or convenient to provide some or all of the 1822516cbf37STim Bird kernel boot arguments with the kernel itself (that is, 1823516cbf37STim Bird to not rely on the boot loader to provide them.) 1824516cbf37STim Bird 1825516cbf37STim Bird To compile command line arguments into the kernel, 1826516cbf37STim Bird set this option to 'Y', then fill in the 1827516cbf37STim Bird the boot arguments in CONFIG_CMDLINE. 1828516cbf37STim Bird 1829516cbf37STim Bird Systems with fully functional boot loaders (i.e. non-embedded) 1830516cbf37STim Bird should leave this option set to 'N'. 1831516cbf37STim Bird 1832516cbf37STim Birdconfig CMDLINE 1833516cbf37STim Bird string "Built-in kernel command string" 1834516cbf37STim Bird depends on CMDLINE_BOOL 1835516cbf37STim Bird default "" 18368f9ca475SIngo Molnar ---help--- 1837516cbf37STim Bird Enter arguments here that should be compiled into the kernel 1838516cbf37STim Bird image and used at boot time. If the boot loader provides a 1839516cbf37STim Bird command line at boot time, it is appended to this string to 1840516cbf37STim Bird form the full kernel command line, when the system boots. 1841516cbf37STim Bird 1842516cbf37STim Bird However, you can use the CONFIG_CMDLINE_OVERRIDE option to 1843516cbf37STim Bird change this behavior. 1844516cbf37STim Bird 1845516cbf37STim Bird In most cases, the command line (whether built-in or provided 1846516cbf37STim Bird by the boot loader) should specify the device for the root 1847516cbf37STim Bird file system. 1848516cbf37STim Bird 1849516cbf37STim Birdconfig CMDLINE_OVERRIDE 1850516cbf37STim Bird bool "Built-in command line overrides boot loader arguments" 1851516cbf37STim Bird depends on CMDLINE_BOOL 18528f9ca475SIngo Molnar ---help--- 1853516cbf37STim Bird Set this option to 'Y' to have the kernel ignore the boot loader 1854516cbf37STim Bird command line, and use ONLY the built-in command line. 1855516cbf37STim Bird 1856516cbf37STim Bird This is used to work around broken boot loaders. This should 1857516cbf37STim Bird be set to 'N' under normal conditions. 1858516cbf37STim Bird 1859506f1d07SSam Ravnborgendmenu 1860506f1d07SSam Ravnborg 1861506f1d07SSam Ravnborgconfig ARCH_ENABLE_MEMORY_HOTPLUG 1862506f1d07SSam Ravnborg def_bool y 1863506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 1864506f1d07SSam Ravnborg 186535551053SGary Hadeconfig ARCH_ENABLE_MEMORY_HOTREMOVE 186635551053SGary Hade def_bool y 186735551053SGary Hade depends on MEMORY_HOTPLUG 186835551053SGary Hade 1869e534c7c5SLee Schermerhornconfig USE_PERCPU_NUMA_NODE_ID 1870645a7919STejun Heo def_bool y 1871e534c7c5SLee Schermerhorn depends on NUMA 1872e534c7c5SLee Schermerhorn 18739491846fSKirill A. Shutemovconfig ARCH_ENABLE_SPLIT_PMD_PTLOCK 18749491846fSKirill A. Shutemov def_bool y 18759491846fSKirill A. Shutemov depends on X86_64 || X86_PAE 18769491846fSKirill A. Shutemov 1877da85f865SBjorn Helgaasmenu "Power management and ACPI options" 1878e279b6c1SSam Ravnborg 1879e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER 18803c2362e6SHarvey Harrison def_bool y 1881e279b6c1SSam Ravnborg depends on X86_64 && HIBERNATION 1882e279b6c1SSam Ravnborg 1883e279b6c1SSam Ravnborgsource "kernel/power/Kconfig" 1884e279b6c1SSam Ravnborg 1885e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig" 1886e279b6c1SSam Ravnborg 1887efafc8b2SFeng Tangsource "drivers/sfi/Kconfig" 1888efafc8b2SFeng Tang 1889a6b68076SAndi Kleenconfig X86_APM_BOOT 18906fc108a0SJan Beulich def_bool y 1891282e5aabSPaul Bolle depends on APM 1892a6b68076SAndi Kleen 1893e279b6c1SSam Ravnborgmenuconfig APM 1894e279b6c1SSam Ravnborg tristate "APM (Advanced Power Management) BIOS support" 1895efefa6f6SIngo Molnar depends on X86_32 && PM_SLEEP 1896e279b6c1SSam Ravnborg ---help--- 1897e279b6c1SSam Ravnborg APM is a BIOS specification for saving power using several different 1898e279b6c1SSam Ravnborg techniques. This is mostly useful for battery powered laptops with 1899e279b6c1SSam Ravnborg APM compliant BIOSes. If you say Y here, the system time will be 1900e279b6c1SSam Ravnborg reset after a RESUME operation, the /proc/apm device will provide 1901e279b6c1SSam Ravnborg battery status information, and user-space programs will receive 1902e279b6c1SSam Ravnborg notification of APM "events" (e.g. battery status change). 1903e279b6c1SSam Ravnborg 1904e279b6c1SSam Ravnborg If you select "Y" here, you can disable actual use of the APM 1905e279b6c1SSam Ravnborg BIOS by passing the "apm=off" option to the kernel at boot time. 1906e279b6c1SSam Ravnborg 1907e279b6c1SSam Ravnborg Note that the APM support is almost completely disabled for 1908e279b6c1SSam Ravnborg machines with more than one CPU. 1909e279b6c1SSam Ravnborg 1910e279b6c1SSam Ravnborg In order to use APM, you will need supporting software. For location 19112dc98fd3SMichael Witten and more information, read <file:Documentation/power/apm-acpi.txt> 19122dc98fd3SMichael Witten and the Battery Powered Linux mini-HOWTO, available from 1913e279b6c1SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 1914e279b6c1SSam Ravnborg 1915e279b6c1SSam Ravnborg This driver does not spin down disk drives (see the hdparm(8) 1916e279b6c1SSam Ravnborg manpage ("man 8 hdparm") for that), and it doesn't turn off 1917e279b6c1SSam Ravnborg VESA-compliant "green" monitors. 1918e279b6c1SSam Ravnborg 1919e279b6c1SSam Ravnborg This driver does not support the TI 4000M TravelMate and the ACER 1920e279b6c1SSam Ravnborg 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1921e279b6c1SSam Ravnborg desktop machines also don't have compliant BIOSes, and this driver 1922e279b6c1SSam Ravnborg may cause those machines to panic during the boot phase. 1923e279b6c1SSam Ravnborg 1924e279b6c1SSam Ravnborg Generally, if you don't have a battery in your machine, there isn't 1925e279b6c1SSam Ravnborg much point in using this driver and you should say N. If you get 1926e279b6c1SSam Ravnborg random kernel OOPSes or reboots that don't seem to be related to 1927e279b6c1SSam Ravnborg anything, try disabling/enabling this option (or disabling/enabling 1928e279b6c1SSam Ravnborg APM in your BIOS). 1929e279b6c1SSam Ravnborg 1930e279b6c1SSam Ravnborg Some other things you should try when experiencing seemingly random, 1931e279b6c1SSam Ravnborg "weird" problems: 1932e279b6c1SSam Ravnborg 1933e279b6c1SSam Ravnborg 1) make sure that you have enough swap space and that it is 1934e279b6c1SSam Ravnborg enabled. 1935e279b6c1SSam Ravnborg 2) pass the "no-hlt" option to the kernel 1936e279b6c1SSam Ravnborg 3) switch on floating point emulation in the kernel and pass 1937e279b6c1SSam Ravnborg the "no387" option to the kernel 1938e279b6c1SSam Ravnborg 4) pass the "floppy=nodma" option to the kernel 1939e279b6c1SSam Ravnborg 5) pass the "mem=4M" option to the kernel (thereby disabling 1940e279b6c1SSam Ravnborg all but the first 4 MB of RAM) 1941e279b6c1SSam Ravnborg 6) make sure that the CPU is not over clocked. 1942e279b6c1SSam Ravnborg 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1943e279b6c1SSam Ravnborg 8) disable the cache from your BIOS settings 1944e279b6c1SSam Ravnborg 9) install a fan for the video card or exchange video RAM 1945e279b6c1SSam Ravnborg 10) install a better fan for the CPU 1946e279b6c1SSam Ravnborg 11) exchange RAM chips 1947e279b6c1SSam Ravnborg 12) exchange the motherboard. 1948e279b6c1SSam Ravnborg 1949e279b6c1SSam Ravnborg To compile this driver as a module, choose M here: the 1950e279b6c1SSam Ravnborg module will be called apm. 1951e279b6c1SSam Ravnborg 1952e279b6c1SSam Ravnborgif APM 1953e279b6c1SSam Ravnborg 1954e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND 1955e279b6c1SSam Ravnborg bool "Ignore USER SUSPEND" 19568f9ca475SIngo Molnar ---help--- 1957e279b6c1SSam Ravnborg This option will ignore USER SUSPEND requests. On machines with a 1958e279b6c1SSam Ravnborg compliant APM BIOS, you want to say N. However, on the NEC Versa M 1959e279b6c1SSam Ravnborg series notebooks, it is necessary to say Y because of a BIOS bug. 1960e279b6c1SSam Ravnborg 1961e279b6c1SSam Ravnborgconfig APM_DO_ENABLE 1962e279b6c1SSam Ravnborg bool "Enable PM at boot time" 1963e279b6c1SSam Ravnborg ---help--- 1964e279b6c1SSam Ravnborg Enable APM features at boot time. From page 36 of the APM BIOS 1965e279b6c1SSam Ravnborg specification: "When disabled, the APM BIOS does not automatically 1966e279b6c1SSam Ravnborg power manage devices, enter the Standby State, enter the Suspend 1967e279b6c1SSam Ravnborg State, or take power saving steps in response to CPU Idle calls." 1968e279b6c1SSam Ravnborg This driver will make CPU Idle calls when Linux is idle (unless this 1969e279b6c1SSam Ravnborg feature is turned off -- see "Do CPU IDLE calls", below). This 1970e279b6c1SSam Ravnborg should always save battery power, but more complicated APM features 1971e279b6c1SSam Ravnborg will be dependent on your BIOS implementation. You may need to turn 1972e279b6c1SSam Ravnborg this option off if your computer hangs at boot time when using APM 1973e279b6c1SSam Ravnborg support, or if it beeps continuously instead of suspending. Turn 1974e279b6c1SSam Ravnborg this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1975e279b6c1SSam Ravnborg T400CDT. This is off by default since most machines do fine without 1976e279b6c1SSam Ravnborg this feature. 1977e279b6c1SSam Ravnborg 1978e279b6c1SSam Ravnborgconfig APM_CPU_IDLE 1979dd8af076SLen Brown depends on CPU_IDLE 1980e279b6c1SSam Ravnborg bool "Make CPU Idle calls when idle" 19818f9ca475SIngo Molnar ---help--- 1982e279b6c1SSam Ravnborg Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 1983e279b6c1SSam Ravnborg On some machines, this can activate improved power savings, such as 1984e279b6c1SSam Ravnborg a slowed CPU clock rate, when the machine is idle. These idle calls 1985e279b6c1SSam Ravnborg are made after the idle loop has run for some length of time (e.g., 1986e279b6c1SSam Ravnborg 333 mS). On some machines, this will cause a hang at boot time or 1987e279b6c1SSam Ravnborg whenever the CPU becomes idle. (On machines with more than one CPU, 1988e279b6c1SSam Ravnborg this option does nothing.) 1989e279b6c1SSam Ravnborg 1990e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK 1991e279b6c1SSam Ravnborg bool "Enable console blanking using APM" 19928f9ca475SIngo Molnar ---help--- 1993e279b6c1SSam Ravnborg Enable console blanking using the APM. Some laptops can use this to 1994e279b6c1SSam Ravnborg turn off the LCD backlight when the screen blanker of the Linux 1995e279b6c1SSam Ravnborg virtual console blanks the screen. Note that this is only used by 1996e279b6c1SSam Ravnborg the virtual console screen blanker, and won't turn off the backlight 1997e279b6c1SSam Ravnborg when using the X Window system. This also doesn't have anything to 1998e279b6c1SSam Ravnborg do with your VESA-compliant power-saving monitor. Further, this 1999e279b6c1SSam Ravnborg option doesn't work for all laptops -- it might not turn off your 2000e279b6c1SSam Ravnborg backlight at all, or it might print a lot of errors to the console, 2001e279b6c1SSam Ravnborg especially if you are using gpm. 2002e279b6c1SSam Ravnborg 2003e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS 2004e279b6c1SSam Ravnborg bool "Allow interrupts during APM BIOS calls" 20058f9ca475SIngo Molnar ---help--- 2006e279b6c1SSam Ravnborg Normally we disable external interrupts while we are making calls to 2007e279b6c1SSam Ravnborg the APM BIOS as a measure to lessen the effects of a badly behaving 2008e279b6c1SSam Ravnborg BIOS implementation. The BIOS should reenable interrupts if it 2009e279b6c1SSam Ravnborg needs to. Unfortunately, some BIOSes do not -- especially those in 2010e279b6c1SSam Ravnborg many of the newer IBM Thinkpads. If you experience hangs when you 2011e279b6c1SSam Ravnborg suspend, try setting this to Y. Otherwise, say N. 2012e279b6c1SSam Ravnborg 2013e279b6c1SSam Ravnborgendif # APM 2014e279b6c1SSam Ravnborg 2015bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig" 2016e279b6c1SSam Ravnborg 2017e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig" 2018e279b6c1SSam Ravnborg 201927471fdbSAndy Henroidsource "drivers/idle/Kconfig" 202027471fdbSAndy Henroid 2021e279b6c1SSam Ravnborgendmenu 2022e279b6c1SSam Ravnborg 2023e279b6c1SSam Ravnborg 2024e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)" 2025e279b6c1SSam Ravnborg 2026e279b6c1SSam Ravnborgconfig PCI 20271ac97018SIngo Molnar bool "PCI support" 20281c858087SAdrian Bunk default y 20298f9ca475SIngo Molnar ---help--- 2030e279b6c1SSam Ravnborg Find out whether you have a PCI motherboard. PCI is the name of a 2031e279b6c1SSam Ravnborg bus system, i.e. the way the CPU talks to the other stuff inside 2032e279b6c1SSam Ravnborg your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2033e279b6c1SSam Ravnborg VESA. If you have PCI, say Y, otherwise N. 2034e279b6c1SSam Ravnborg 2035e279b6c1SSam Ravnborgchoice 2036e279b6c1SSam Ravnborg prompt "PCI access mode" 2037efefa6f6SIngo Molnar depends on X86_32 && PCI 2038e279b6c1SSam Ravnborg default PCI_GOANY 2039e279b6c1SSam Ravnborg ---help--- 2040e279b6c1SSam Ravnborg On PCI systems, the BIOS can be used to detect the PCI devices and 2041e279b6c1SSam Ravnborg determine their configuration. However, some old PCI motherboards 2042e279b6c1SSam Ravnborg have BIOS bugs and may crash if this is done. Also, some embedded 2043e279b6c1SSam Ravnborg PCI-based systems don't have any BIOS at all. Linux can also try to 2044e279b6c1SSam Ravnborg detect the PCI hardware directly without using the BIOS. 2045e279b6c1SSam Ravnborg 2046e279b6c1SSam Ravnborg With this option, you can specify how Linux should detect the 2047e279b6c1SSam Ravnborg PCI devices. If you choose "BIOS", the BIOS will be used, 2048e279b6c1SSam Ravnborg if you choose "Direct", the BIOS won't be used, and if you 2049e279b6c1SSam Ravnborg choose "MMConfig", then PCI Express MMCONFIG will be used. 2050e279b6c1SSam Ravnborg If you choose "Any", the kernel will try MMCONFIG, then the 2051e279b6c1SSam Ravnborg direct access method and falls back to the BIOS if that doesn't 2052e279b6c1SSam Ravnborg work. If unsure, go with the default, which is "Any". 2053e279b6c1SSam Ravnborg 2054e279b6c1SSam Ravnborgconfig PCI_GOBIOS 2055e279b6c1SSam Ravnborg bool "BIOS" 2056e279b6c1SSam Ravnborg 2057e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG 2058e279b6c1SSam Ravnborg bool "MMConfig" 2059e279b6c1SSam Ravnborg 2060e279b6c1SSam Ravnborgconfig PCI_GODIRECT 2061e279b6c1SSam Ravnborg bool "Direct" 2062e279b6c1SSam Ravnborg 20633ef0e1f8SAndres Salomonconfig PCI_GOOLPC 206476fb6570SDaniel Drake bool "OLPC XO-1" 20653ef0e1f8SAndres Salomon depends on OLPC 20663ef0e1f8SAndres Salomon 20672bdd1b03SAndres Salomonconfig PCI_GOANY 20682bdd1b03SAndres Salomon bool "Any" 20692bdd1b03SAndres Salomon 2070e279b6c1SSam Ravnborgendchoice 2071e279b6c1SSam Ravnborg 2072e279b6c1SSam Ravnborgconfig PCI_BIOS 20733c2362e6SHarvey Harrison def_bool y 2074efefa6f6SIngo Molnar depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2075e279b6c1SSam Ravnborg 2076e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2077e279b6c1SSam Ravnborgconfig PCI_DIRECT 20783c2362e6SHarvey Harrison def_bool y 20790aba496fSShaohua Li depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2080e279b6c1SSam Ravnborg 2081e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 20823c2362e6SHarvey Harrison def_bool y 20835f0db7a2SFeng Tang depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2084e279b6c1SSam Ravnborg 20853ef0e1f8SAndres Salomonconfig PCI_OLPC 20862bdd1b03SAndres Salomon def_bool y 20872bdd1b03SAndres Salomon depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 20883ef0e1f8SAndres Salomon 2089b5401a96SAlex Nixonconfig PCI_XEN 2090b5401a96SAlex Nixon def_bool y 2091b5401a96SAlex Nixon depends on PCI && XEN 2092b5401a96SAlex Nixon select SWIOTLB_XEN 2093b5401a96SAlex Nixon 2094e279b6c1SSam Ravnborgconfig PCI_DOMAINS 20953c2362e6SHarvey Harrison def_bool y 2096e279b6c1SSam Ravnborg depends on PCI 2097e279b6c1SSam Ravnborg 2098e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 2099e279b6c1SSam Ravnborg bool "Support mmconfig PCI config space access" 2100e279b6c1SSam Ravnborg depends on X86_64 && PCI && ACPI 2101e279b6c1SSam Ravnborg 21023f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK 21036a108a14SDavid Rientjes bool "Read CNB20LE Host Bridge Windows" if EXPERT 21046ea30386SKees Cook depends on PCI 21053f6ea84aSIra W. Snyder help 21063f6ea84aSIra W. Snyder Read the PCI windows out of the CNB20LE host bridge. This allows 21073f6ea84aSIra W. Snyder PCI hotplug to work on systems with the CNB20LE chipset which do 21083f6ea84aSIra W. Snyder not have ACPI. 21093f6ea84aSIra W. Snyder 211064a5fed6SBjorn Helgaas There's no public spec for this chipset, and this functionality 211164a5fed6SBjorn Helgaas is known to be incomplete. 211264a5fed6SBjorn Helgaas 211364a5fed6SBjorn Helgaas You should say N unless you know you need this. 211464a5fed6SBjorn Helgaas 2115e279b6c1SSam Ravnborgsource "drivers/pci/pcie/Kconfig" 2116e279b6c1SSam Ravnborg 2117e279b6c1SSam Ravnborgsource "drivers/pci/Kconfig" 2118e279b6c1SSam Ravnborg 21191c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA. 2120e279b6c1SSam Ravnborgconfig ISA_DMA_API 21211c00f016SDavid Rientjes bool "ISA-style DMA support" if (X86_64 && EXPERT) 21221c00f016SDavid Rientjes default y 21231c00f016SDavid Rientjes help 21241c00f016SDavid Rientjes Enables ISA-style DMA support for devices requiring such controllers. 21251c00f016SDavid Rientjes If unsure, say Y. 2126e279b6c1SSam Ravnborg 2127e279b6c1SSam Ravnborgif X86_32 2128e279b6c1SSam Ravnborg 2129e279b6c1SSam Ravnborgconfig ISA 2130e279b6c1SSam Ravnborg bool "ISA support" 21318f9ca475SIngo Molnar ---help--- 2132e279b6c1SSam Ravnborg Find out whether you have ISA slots on your motherboard. ISA is the 2133e279b6c1SSam Ravnborg name of a bus system, i.e. the way the CPU talks to the other stuff 2134e279b6c1SSam Ravnborg inside your box. Other bus systems are PCI, EISA, MicroChannel 2135e279b6c1SSam Ravnborg (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2136e279b6c1SSam Ravnborg newer boards don't support it. If you have ISA, say Y, otherwise N. 2137e279b6c1SSam Ravnborg 2138e279b6c1SSam Ravnborgconfig EISA 2139e279b6c1SSam Ravnborg bool "EISA support" 2140e279b6c1SSam Ravnborg depends on ISA 2141e279b6c1SSam Ravnborg ---help--- 2142e279b6c1SSam Ravnborg The Extended Industry Standard Architecture (EISA) bus was 2143e279b6c1SSam Ravnborg developed as an open alternative to the IBM MicroChannel bus. 2144e279b6c1SSam Ravnborg 2145e279b6c1SSam Ravnborg The EISA bus provided some of the features of the IBM MicroChannel 2146e279b6c1SSam Ravnborg bus while maintaining backward compatibility with cards made for 2147e279b6c1SSam Ravnborg the older ISA bus. The EISA bus saw limited use between 1988 and 2148e279b6c1SSam Ravnborg 1995 when it was made obsolete by the PCI bus. 2149e279b6c1SSam Ravnborg 2150e279b6c1SSam Ravnborg Say Y here if you are building a kernel for an EISA-based machine. 2151e279b6c1SSam Ravnborg 2152e279b6c1SSam Ravnborg Otherwise, say N. 2153e279b6c1SSam Ravnborg 2154e279b6c1SSam Ravnborgsource "drivers/eisa/Kconfig" 2155e279b6c1SSam Ravnborg 2156e279b6c1SSam Ravnborgconfig SCx200 2157e279b6c1SSam Ravnborg tristate "NatSemi SCx200 support" 21588f9ca475SIngo Molnar ---help--- 2159e279b6c1SSam Ravnborg This provides basic support for National Semiconductor's 2160e279b6c1SSam Ravnborg (now AMD's) Geode processors. The driver probes for the 2161e279b6c1SSam Ravnborg PCI-IDs of several on-chip devices, so its a good dependency 2162e279b6c1SSam Ravnborg for other scx200_* drivers. 2163e279b6c1SSam Ravnborg 2164e279b6c1SSam Ravnborg If compiled as a module, the driver is named scx200. 2165e279b6c1SSam Ravnborg 2166e279b6c1SSam Ravnborgconfig SCx200HR_TIMER 2167e279b6c1SSam Ravnborg tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2168592913ecSJohn Stultz depends on SCx200 2169e279b6c1SSam Ravnborg default y 21708f9ca475SIngo Molnar ---help--- 2171e279b6c1SSam Ravnborg This driver provides a clocksource built upon the on-chip 2172e279b6c1SSam Ravnborg 27MHz high-resolution timer. Its also a workaround for 2173e279b6c1SSam Ravnborg NSC Geode SC-1100's buggy TSC, which loses time when the 2174e279b6c1SSam Ravnborg processor goes idle (as is done by the scheduler). The 2175e279b6c1SSam Ravnborg other workaround is idle=poll boot option. 2176e279b6c1SSam Ravnborg 21773ef0e1f8SAndres Salomonconfig OLPC 21783ef0e1f8SAndres Salomon bool "One Laptop Per Child support" 217954008979SThomas Gleixner depends on !X86_PAE 21803c554946SAndres Salomon select GPIOLIB 2181dc3119e7SThomas Gleixner select OF 218245bb1674SDaniel Drake select OF_PROMTREE 2183b4e51854SGrant Likely select IRQ_DOMAIN 21848f9ca475SIngo Molnar ---help--- 21853ef0e1f8SAndres Salomon Add support for detecting the unique features of the OLPC 21863ef0e1f8SAndres Salomon XO hardware. 21873ef0e1f8SAndres Salomon 2188a3128588SDaniel Drakeconfig OLPC_XO1_PM 2189a3128588SDaniel Drake bool "OLPC XO-1 Power Management" 219097c4cb71SDaniel Drake depends on OLPC && MFD_CS5535 && PM_SLEEP 2191a3128588SDaniel Drake select MFD_CORE 2192bf1ebf00SDaniel Drake ---help--- 219397c4cb71SDaniel Drake Add support for poweroff and suspend of the OLPC XO-1 laptop. 2194bf1ebf00SDaniel Drake 2195cfee9597SDaniel Drakeconfig OLPC_XO1_RTC 2196cfee9597SDaniel Drake bool "OLPC XO-1 Real Time Clock" 2197cfee9597SDaniel Drake depends on OLPC_XO1_PM && RTC_DRV_CMOS 2198cfee9597SDaniel Drake ---help--- 2199cfee9597SDaniel Drake Add support for the XO-1 real time clock, which can be used as a 2200cfee9597SDaniel Drake programmable wakeup source. 2201cfee9597SDaniel Drake 22027feda8e9SDaniel Drakeconfig OLPC_XO1_SCI 22037feda8e9SDaniel Drake bool "OLPC XO-1 SCI extras" 2204d8d01a63SDaniel Drake depends on OLPC && OLPC_XO1_PM 2205ed8e47feSRandy Dunlap depends on INPUT=y 2206d8d01a63SDaniel Drake select POWER_SUPPLY 22077feda8e9SDaniel Drake select GPIO_CS5535 22087feda8e9SDaniel Drake select MFD_CORE 22097feda8e9SDaniel Drake ---help--- 22107feda8e9SDaniel Drake Add support for SCI-based features of the OLPC XO-1 laptop: 22117bc74b3dSDaniel Drake - EC-driven system wakeups 22127feda8e9SDaniel Drake - Power button 22137bc74b3dSDaniel Drake - Ebook switch 22142cf2baeaSDaniel Drake - Lid switch 2215e1040ac6SDaniel Drake - AC adapter status updates 2216e1040ac6SDaniel Drake - Battery status updates 22177feda8e9SDaniel Drake 2218a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI 2219a0f30f59SDaniel Drake bool "OLPC XO-1.5 SCI extras" 2220d8d01a63SDaniel Drake depends on OLPC && ACPI 2221d8d01a63SDaniel Drake select POWER_SUPPLY 2222a0f30f59SDaniel Drake ---help--- 2223a0f30f59SDaniel Drake Add support for SCI-based features of the OLPC XO-1.5 laptop: 2224a0f30f59SDaniel Drake - EC-driven system wakeups 2225a0f30f59SDaniel Drake - AC adapter status updates 2226a0f30f59SDaniel Drake - Battery status updates 2227e279b6c1SSam Ravnborg 2228d4f3e350SEd Wildgooseconfig ALIX 2229d4f3e350SEd Wildgoose bool "PCEngines ALIX System Support (LED setup)" 2230d4f3e350SEd Wildgoose select GPIOLIB 2231d4f3e350SEd Wildgoose ---help--- 2232d4f3e350SEd Wildgoose This option enables system support for the PCEngines ALIX. 2233d4f3e350SEd Wildgoose At present this just sets up LEDs for GPIO control on 2234d4f3e350SEd Wildgoose ALIX2/3/6 boards. However, other system specific setup should 2235d4f3e350SEd Wildgoose get added here. 2236d4f3e350SEd Wildgoose 2237d4f3e350SEd Wildgoose Note: You must still enable the drivers for GPIO and LED support 2238d4f3e350SEd Wildgoose (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2239d4f3e350SEd Wildgoose 2240d4f3e350SEd Wildgoose Note: You have to set alix.force=1 for boards with Award BIOS. 2241d4f3e350SEd Wildgoose 2242da4e3302SPhilip Prindevilleconfig NET5501 2243da4e3302SPhilip Prindeville bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2244da4e3302SPhilip Prindeville select GPIOLIB 2245da4e3302SPhilip Prindeville ---help--- 2246da4e3302SPhilip Prindeville This option enables system support for the Soekris Engineering net5501. 2247da4e3302SPhilip Prindeville 22483197059aSPhilip A. Prindevilleconfig GEOS 22493197059aSPhilip A. Prindeville bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 22503197059aSPhilip A. Prindeville select GPIOLIB 22513197059aSPhilip A. Prindeville depends on DMI 22523197059aSPhilip A. Prindeville ---help--- 22533197059aSPhilip A. Prindeville This option enables system support for the Traverse Technologies GEOS. 22543197059aSPhilip A. Prindeville 22557d029125SVivien Didelotconfig TS5500 22567d029125SVivien Didelot bool "Technologic Systems TS-5500 platform support" 22577d029125SVivien Didelot depends on MELAN 22587d029125SVivien Didelot select CHECK_SIGNATURE 22597d029125SVivien Didelot select NEW_LEDS 22607d029125SVivien Didelot select LEDS_CLASS 22617d029125SVivien Didelot ---help--- 22627d029125SVivien Didelot This option enables system support for the Technologic Systems TS-5500. 22637d029125SVivien Didelot 2264e279b6c1SSam Ravnborgendif # X86_32 2265e279b6c1SSam Ravnborg 226623ac4ae8SAndreas Herrmannconfig AMD_NB 2267e279b6c1SSam Ravnborg def_bool y 22680e152cd7SBorislav Petkov depends on CPU_SUP_AMD && PCI 2269e279b6c1SSam Ravnborg 2270e279b6c1SSam Ravnborgsource "drivers/pcmcia/Kconfig" 2271e279b6c1SSam Ravnborg 2272e279b6c1SSam Ravnborgsource "drivers/pci/hotplug/Kconfig" 2273e279b6c1SSam Ravnborg 2274388b78adSAlexandre Bounineconfig RAPIDIO 2275fdf90abcSAlexandre Bounine tristate "RapidIO support" 2276388b78adSAlexandre Bounine depends on PCI 2277388b78adSAlexandre Bounine default n 2278388b78adSAlexandre Bounine help 2279fdf90abcSAlexandre Bounine If enabled this option will include drivers and the core 2280388b78adSAlexandre Bounine infrastructure code to support RapidIO interconnect devices. 2281388b78adSAlexandre Bounine 2282388b78adSAlexandre Bouninesource "drivers/rapidio/Kconfig" 2283388b78adSAlexandre Bounine 2284e3263ab3SDavid Herrmannconfig X86_SYSFB 2285e3263ab3SDavid Herrmann bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2286e3263ab3SDavid Herrmann help 2287e3263ab3SDavid Herrmann Firmwares often provide initial graphics framebuffers so the BIOS, 2288e3263ab3SDavid Herrmann bootloader or kernel can show basic video-output during boot for 2289e3263ab3SDavid Herrmann user-guidance and debugging. Historically, x86 used the VESA BIOS 2290e3263ab3SDavid Herrmann Extensions and EFI-framebuffers for this, which are mostly limited 2291e3263ab3SDavid Herrmann to x86. 2292e3263ab3SDavid Herrmann This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2293e3263ab3SDavid Herrmann framebuffers so the new generic system-framebuffer drivers can be 2294e3263ab3SDavid Herrmann used on x86. If the framebuffer is not compatible with the generic 2295e3263ab3SDavid Herrmann modes, it is adverticed as fallback platform framebuffer so legacy 2296e3263ab3SDavid Herrmann drivers like efifb, vesafb and uvesafb can pick it up. 2297e3263ab3SDavid Herrmann If this option is not selected, all system framebuffers are always 2298e3263ab3SDavid Herrmann marked as fallback platform framebuffers as usual. 2299e3263ab3SDavid Herrmann 2300e3263ab3SDavid Herrmann Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2301e3263ab3SDavid Herrmann not be able to pick up generic system framebuffers if this option 2302e3263ab3SDavid Herrmann is selected. You are highly encouraged to enable simplefb as 2303e3263ab3SDavid Herrmann replacement if you select this option. simplefb can correctly deal 2304e3263ab3SDavid Herrmann with generic system framebuffers. But you should still keep vesafb 2305e3263ab3SDavid Herrmann and others enabled as fallback if a system framebuffer is 2306e3263ab3SDavid Herrmann incompatible with simplefb. 2307e3263ab3SDavid Herrmann 2308e3263ab3SDavid Herrmann If unsure, say Y. 2309e3263ab3SDavid Herrmann 2310e279b6c1SSam Ravnborgendmenu 2311e279b6c1SSam Ravnborg 2312e279b6c1SSam Ravnborg 2313e279b6c1SSam Ravnborgmenu "Executable file formats / Emulations" 2314e279b6c1SSam Ravnborg 2315e279b6c1SSam Ravnborgsource "fs/Kconfig.binfmt" 2316e279b6c1SSam Ravnborg 2317e279b6c1SSam Ravnborgconfig IA32_EMULATION 2318e279b6c1SSam Ravnborg bool "IA32 Emulation" 2319e279b6c1SSam Ravnborg depends on X86_64 2320d1603990SRandy Dunlap select BINFMT_ELF 2321a97f52e6SRoland McGrath select COMPAT_BINFMT_ELF 2322af1839ebSCatalin Marinas select HAVE_UID16 23238f9ca475SIngo Molnar ---help--- 23245fd92e65SH. J. Lu Include code to run legacy 32-bit programs under a 23255fd92e65SH. J. Lu 64-bit kernel. You should likely turn this on, unless you're 23265fd92e65SH. J. Lu 100% sure that you don't have any 32-bit programs left. 2327e279b6c1SSam Ravnborg 2328e279b6c1SSam Ravnborgconfig IA32_AOUT 2329e279b6c1SSam Ravnborg tristate "IA32 a.out support" 23306b213e1bSDavid Woodhouse depends on IA32_EMULATION 23318f9ca475SIngo Molnar ---help--- 2332e279b6c1SSam Ravnborg Support old a.out binaries in the 32bit emulation. 2333e279b6c1SSam Ravnborg 23340bf62763SH. Peter Anvinconfig X86_X32 23356ea30386SKees Cook bool "x32 ABI for 64-bit mode" 23366ea30386SKees Cook depends on X86_64 && IA32_EMULATION 23375fd92e65SH. J. Lu ---help--- 23385fd92e65SH. J. Lu Include code to run binaries for the x32 native 32-bit ABI 23395fd92e65SH. J. Lu for 64-bit processors. An x32 process gets access to the 23405fd92e65SH. J. Lu full 64-bit register file and wide data path while leaving 23415fd92e65SH. J. Lu pointers at 32 bits for smaller memory footprint. 23425fd92e65SH. J. Lu 23435fd92e65SH. J. Lu You will need a recent binutils (2.22 or later) with 23445fd92e65SH. J. Lu elf32_x86_64 support enabled to compile a kernel with this 23455fd92e65SH. J. Lu option set. 23465fd92e65SH. J. Lu 2347e279b6c1SSam Ravnborgconfig COMPAT 23483c2362e6SHarvey Harrison def_bool y 23490bf62763SH. Peter Anvin depends on IA32_EMULATION || X86_X32 235048b25c43SChris Metcalf select ARCH_WANT_OLD_COMPAT_IPC 2351e279b6c1SSam Ravnborg 23523120e25eSJan Beulichif COMPAT 2353e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT 23543120e25eSJan Beulich def_bool y 2355e279b6c1SSam Ravnborg 2356e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT 23573c2362e6SHarvey Harrison def_bool y 23583120e25eSJan Beulich depends on SYSVIPC 2359e279b6c1SSam Ravnborg 2360ee009e4aSDavid Howellsconfig KEYS_COMPAT 23613120e25eSJan Beulich def_bool y 23623120e25eSJan Beulich depends on KEYS 23633120e25eSJan Beulichendif 2364ee009e4aSDavid Howells 2365e279b6c1SSam Ravnborgendmenu 2366e279b6c1SSam Ravnborg 2367e279b6c1SSam Ravnborg 2368e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP 2369e5beae16SKeith Packard def_bool y 2370e5beae16SKeith Packard depends on X86_32 2371e5beae16SKeith Packard 23724692d77fSAlessandro Rubiniconfig X86_DEV_DMA_OPS 23734692d77fSAlessandro Rubini bool 237483125a3aSAlessandro Rubini depends on X86_64 || STA2X11 23754692d77fSAlessandro Rubini 2376f7219a53SAlessandro Rubiniconfig X86_DMA_REMAP 2377f7219a53SAlessandro Rubini bool 237883125a3aSAlessandro Rubini depends on STA2X11 2379f7219a53SAlessandro Rubini 238046184415SDavid E. Boxconfig IOSF_MBI 238146184415SDavid E. Box bool 238246184415SDavid E. Box depends on PCI 238346184415SDavid E. Box ---help--- 238446184415SDavid E. Box To be selected by modules requiring access to the Intel OnChip System 238546184415SDavid E. Box Fabric (IOSF) Sideband MailBox Interface (MBI). For MBI platforms 238646184415SDavid E. Box enumerable by PCI. 238746184415SDavid E. Box 2388e279b6c1SSam Ravnborgsource "net/Kconfig" 2389e279b6c1SSam Ravnborg 2390e279b6c1SSam Ravnborgsource "drivers/Kconfig" 2391e279b6c1SSam Ravnborg 2392e279b6c1SSam Ravnborgsource "drivers/firmware/Kconfig" 2393e279b6c1SSam Ravnborg 2394e279b6c1SSam Ravnborgsource "fs/Kconfig" 2395e279b6c1SSam Ravnborg 2396e279b6c1SSam Ravnborgsource "arch/x86/Kconfig.debug" 2397e279b6c1SSam Ravnborg 2398e279b6c1SSam Ravnborgsource "security/Kconfig" 2399e279b6c1SSam Ravnborg 2400e279b6c1SSam Ravnborgsource "crypto/Kconfig" 2401e279b6c1SSam Ravnborg 2402edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig" 2403edf88417SAvi Kivity 2404e279b6c1SSam Ravnborgsource "lib/Kconfig" 2405