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 294468dd76SMel Gorman select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 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 449c5a3621SAkinobu Mita select HAVE_DMA_CONTIGUOUS 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 1082bf01f9fSCyrill Gorcunov select HAVE_ARCH_SOFT_DIRTY if X86_64 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 124bd01ec1aSWaiman Long select ARCH_USE_QUEUE_RWLOCK 12515ce1f71SAl Viro select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION 1265b3eb3adSAl Viro select OLD_SIGACTION if X86_32 1275b3eb3adSAl Viro select COMPAT_OLD_SIGACTION if IA32_EMULATION 1283195ef59SPrarit Bhargava select RTC_LIB 129d1a1dc0bSDave Hansen select HAVE_DEBUG_STACKOVERFLOW 130a2cd11f7SFrederic Weisbecker select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 13119952a92SKees Cook select HAVE_CC_STACKPROTECTOR 1322b9c1f03SArd Biesheuvel select GENERIC_CPU_AUTOPROBE 1337a017721SAKASHI Takahiro select HAVE_ARCH_AUDITSYSCALL 1347d8330a5SBalbir Singh 135ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER 1363120e25eSJan Beulich def_bool y 1373120e25eSJan Beulich depends on KPROBES || PERF_EVENTS || UPROBES 138ba7e4d13SIngo Molnar 13951b26adaSLinus Torvaldsconfig OUTPUT_FORMAT 14051b26adaSLinus Torvalds string 14151b26adaSLinus Torvalds default "elf32-i386" if X86_32 14251b26adaSLinus Torvalds default "elf64-x86-64" if X86_64 14351b26adaSLinus Torvalds 14473531905SSam Ravnborgconfig ARCH_DEFCONFIG 145b9b39bfbSSam Ravnborg string 14673531905SSam Ravnborg default "arch/x86/configs/i386_defconfig" if X86_32 14773531905SSam Ravnborg default "arch/x86/configs/x86_64_defconfig" if X86_64 148b9b39bfbSSam Ravnborg 1498d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT 1503c2362e6SHarvey Harrison def_bool y 1518d5fffb9SSam Ravnborg 1528d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT 1533c2362e6SHarvey Harrison def_bool y 1548d5fffb9SSam Ravnborg 155aa7d9350SHeiko Carstensconfig HAVE_LATENCYTOP_SUPPORT 156aa7d9350SHeiko Carstens def_bool y 157aa7d9350SHeiko Carstens 1588d5fffb9SSam Ravnborgconfig MMU 1593c2362e6SHarvey Harrison def_bool y 1608d5fffb9SSam Ravnborg 1618d5fffb9SSam Ravnborgconfig SBUS 1628d5fffb9SSam Ravnborg bool 1638d5fffb9SSam Ravnborg 1643bc4e459SFUJITA Tomonoriconfig NEED_DMA_MAP_STATE 1653120e25eSJan Beulich def_bool y 1663120e25eSJan Beulich depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG 1673bc4e459SFUJITA Tomonori 16818e98307SFUJITA Tomonoriconfig NEED_SG_DMA_LENGTH 1694a14d84eSAndrew Morton def_bool y 17018e98307SFUJITA Tomonori 1718d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA 1723120e25eSJan Beulich def_bool y 1733120e25eSJan Beulich depends on ISA_DMA_API 1748d5fffb9SSam Ravnborg 1758d5fffb9SSam Ravnborgconfig GENERIC_BUG 1763c2362e6SHarvey Harrison def_bool y 1778d5fffb9SSam Ravnborg depends on BUG 178b93a531eSJan Beulich select GENERIC_BUG_RELATIVE_POINTERS if X86_64 179b93a531eSJan Beulich 180b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS 181b93a531eSJan Beulich bool 1828d5fffb9SSam Ravnborg 1838d5fffb9SSam Ravnborgconfig GENERIC_HWEIGHT 1843c2362e6SHarvey Harrison def_bool y 1858d5fffb9SSam Ravnborg 1868d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC 1873120e25eSJan Beulich def_bool y 1883120e25eSJan Beulich depends on ISA_DMA_API 1898d5fffb9SSam Ravnborg 1901032c0baSSam Ravnborgconfig RWSEM_XCHGADD_ALGORITHM 1913120e25eSJan Beulich def_bool y 1921032c0baSSam Ravnborg 1931032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY 1941032c0baSSam Ravnborg def_bool y 1951032c0baSSam Ravnborg 1969a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX 1979a0b8415Svenkatesh.pallipadi@intel.com def_bool y 1988d5fffb9SSam Ravnborg 1991b27d05bSPekka Enbergconfig ARCH_HAS_CACHE_LINE_SIZE 2001b27d05bSPekka Enberg def_bool y 2011b27d05bSPekka Enberg 202dd5af90aSMike Travisconfig HAVE_SETUP_PER_CPU_AREA 20389c9c4c5SBrian Gerst def_bool y 204b32ef636Stravis@sgi.com 20508fc4580STejun Heoconfig NEED_PER_CPU_EMBED_FIRST_CHUNK 20608fc4580STejun Heo def_bool y 20708fc4580STejun Heo 20808fc4580STejun Heoconfig NEED_PER_CPU_PAGE_FIRST_CHUNK 20911124411STejun Heo def_bool y 21011124411STejun Heo 211801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE 212801e4062SJohannes Berg def_bool y 213801e4062SJohannes Berg 214f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE 215f4cb5700SJohannes Berg def_bool y 216f4cb5700SJohannes Berg 217cfe28c5dSSteve Capperconfig ARCH_WANT_HUGE_PMD_SHARE 218cfe28c5dSSteve Capper def_bool y 219cfe28c5dSSteve Capper 22053313b2cSSteve Capperconfig ARCH_WANT_GENERAL_HUGETLB 22153313b2cSSteve Capper def_bool y 22253313b2cSSteve Capper 2238d5fffb9SSam Ravnborgconfig ZONE_DMA32 2248d5fffb9SSam Ravnborg bool 2258d5fffb9SSam Ravnborg default X86_64 2268d5fffb9SSam Ravnborg 2278d5fffb9SSam Ravnborgconfig AUDIT_ARCH 2288d5fffb9SSam Ravnborg bool 2298d5fffb9SSam Ravnborg default X86_64 2308d5fffb9SSam Ravnborg 231765c68bdSIngo Molnarconfig ARCH_SUPPORTS_OPTIMIZED_INLINING 232765c68bdSIngo Molnar def_bool y 233765c68bdSIngo Molnar 2346a11f75bSAkinobu Mitaconfig ARCH_SUPPORTS_DEBUG_PAGEALLOC 2356a11f75bSAkinobu Mita def_bool y 2366a11f75bSAkinobu Mita 23769575d38SShane Wangconfig HAVE_INTEL_TXT 23869575d38SShane Wang def_bool y 2396ea30386SKees Cook depends on INTEL_IOMMU && ACPI 24069575d38SShane Wang 2416b0c3d44SSam Ravnborgconfig X86_32_SMP 2426b0c3d44SSam Ravnborg def_bool y 2436b0c3d44SSam Ravnborg depends on X86_32 && SMP 2446b0c3d44SSam Ravnborg 2456b0c3d44SSam Ravnborgconfig X86_64_SMP 2466b0c3d44SSam Ravnborg def_bool y 2476b0c3d44SSam Ravnborg depends on X86_64 && SMP 2486b0c3d44SSam Ravnborg 2498d5fffb9SSam Ravnborgconfig X86_HT 2506fc108a0SJan Beulich def_bool y 251ee0011a7SAdrian Bunk depends on SMP 2528d5fffb9SSam Ravnborg 253ccbeed3aSTejun Heoconfig X86_32_LAZY_GS 254ccbeed3aSTejun Heo def_bool y 25560a5317fSTejun Heo depends on X86_32 && !CC_STACKPROTECTOR 256ccbeed3aSTejun Heo 257d61931d8SBorislav Petkovconfig ARCH_HWEIGHT_CFLAGS 258d61931d8SBorislav Petkov string 259d61931d8SBorislav Petkov default "-fcall-saved-ecx -fcall-saved-edx" if X86_32 260d61931d8SBorislav 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 261d61931d8SBorislav Petkov 2622b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES 2632b144498SSrikar Dronamraju def_bool y 2642b144498SSrikar Dronamraju 265d20642f0SRob Herringconfig FIX_EARLYCON_MEM 266d20642f0SRob Herring def_bool y 267d20642f0SRob Herring 268506f1d07SSam Ravnborgsource "init/Kconfig" 269dc52ddc0SMatt Helsleysource "kernel/Kconfig.freezer" 2708d5fffb9SSam Ravnborg 271506f1d07SSam Ravnborgmenu "Processor type and features" 272506f1d07SSam Ravnborg 2735ee71535SRandy Dunlapconfig ZONE_DMA 2745ee71535SRandy Dunlap bool "DMA memory allocation support" if EXPERT 2755ee71535SRandy Dunlap default y 2765ee71535SRandy Dunlap help 2775ee71535SRandy Dunlap DMA memory allocation support allows devices with less than 32-bit 2785ee71535SRandy Dunlap addressing to allocate within the first 16MB of address space. 2795ee71535SRandy Dunlap Disable if no such devices will be used. 2805ee71535SRandy Dunlap 2815ee71535SRandy Dunlap If unsure, say Y. 2825ee71535SRandy Dunlap 283506f1d07SSam Ravnborgconfig SMP 284506f1d07SSam Ravnborg bool "Symmetric multi-processing support" 285506f1d07SSam Ravnborg ---help--- 286506f1d07SSam Ravnborg This enables support for systems with more than one CPU. If you have 2874a474157SRobert Graffham a system with only one CPU, say N. If you have a system with more 2884a474157SRobert Graffham than one CPU, say Y. 289506f1d07SSam Ravnborg 2904a474157SRobert Graffham If you say N here, the kernel will run on uni- and multiprocessor 291506f1d07SSam Ravnborg machines, but will use only one CPU of a multiprocessor machine. If 292506f1d07SSam Ravnborg you say Y here, the kernel will run on many, but not all, 2934a474157SRobert Graffham uniprocessor machines. On a uniprocessor machine, the kernel 294506f1d07SSam Ravnborg will run faster if you say N here. 295506f1d07SSam Ravnborg 296506f1d07SSam Ravnborg Note that if you say Y here and choose architecture "586" or 297506f1d07SSam Ravnborg "Pentium" under "Processor family", the kernel will not work on 486 298506f1d07SSam Ravnborg architectures. Similarly, multiprocessor kernels for the "PPro" 299506f1d07SSam Ravnborg architecture may not work on all Pentium based boards. 300506f1d07SSam Ravnborg 301506f1d07SSam Ravnborg People using multiprocessor machines who say Y here should also say 302506f1d07SSam Ravnborg Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 303506f1d07SSam Ravnborg Management" code will be disabled if you say Y here. 304506f1d07SSam Ravnborg 305395cf969SPaul Bolle See also <file:Documentation/x86/i386/IO-APIC.txt>, 306506f1d07SSam Ravnborg <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 307506f1d07SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 308506f1d07SSam Ravnborg 309506f1d07SSam Ravnborg If you don't know what to do here, say N. 310506f1d07SSam Ravnborg 31106cd9a7dSYinghai Luconfig X86_X2APIC 31206cd9a7dSYinghai Lu bool "Support x2apic" 313d3f13810SSuresh Siddha depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP 31406cd9a7dSYinghai Lu ---help--- 31506cd9a7dSYinghai Lu This enables x2apic support on CPUs that have this feature. 31606cd9a7dSYinghai Lu 31706cd9a7dSYinghai Lu This allows 32-bit apic IDs (so it can support very large systems), 31806cd9a7dSYinghai Lu and accesses the local apic via MSRs not via mmio. 31906cd9a7dSYinghai Lu 32006cd9a7dSYinghai Lu If you don't know what to do here, say N. 32106cd9a7dSYinghai Lu 3226695c85bSYinghai Luconfig X86_MPPARSE 3236e87f9b7SBin Gao bool "Enable MPS table" if ACPI || SFI 3247a527688SJan Beulich default y 3255ab74722SIngo Molnar depends on X86_LOCAL_APIC 3268f9ca475SIngo Molnar ---help--- 3276695c85bSYinghai Lu For old smp systems that do not have proper acpi support. Newer systems 3286695c85bSYinghai Lu (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 3296695c85bSYinghai Lu 33026f7ef14SYinghai Luconfig X86_BIGSMP 33126f7ef14SYinghai Lu bool "Support for big SMP systems with more than 8 CPUs" 33226f7ef14SYinghai Lu depends on X86_32 && SMP 3338f9ca475SIngo Molnar ---help--- 33426f7ef14SYinghai Lu This option is needed for the systems that have more than 8 CPUs 335506f1d07SSam Ravnborg 336ddd70cf9SJun Nakajimaconfig GOLDFISH 337ddd70cf9SJun Nakajima def_bool y 338ddd70cf9SJun Nakajima depends on X86_GOLDFISH 339ddd70cf9SJun Nakajima 3408425091fSRavikiran G Thirumalaiif X86_32 341c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 342c5c606d9SRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 343c5c606d9SRavikiran G Thirumalai default y 3448f9ca475SIngo Molnar ---help--- 34506ac8346SIngo Molnar If you disable this option then the kernel will only support 34606ac8346SIngo Molnar standard PC platforms. (which covers the vast majority of 34706ac8346SIngo Molnar systems out there.) 34806ac8346SIngo Molnar 3498425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 3508425091fSRavikiran G Thirumalai for the following (non-PC) 32 bit x86 platforms: 351cb7b8023SBen Hutchings Goldfish (Android emulator) 3528425091fSRavikiran G Thirumalai AMD Elan 3538425091fSRavikiran G Thirumalai RDC R-321x SoC 3548425091fSRavikiran G Thirumalai SGI 320/540 (Visual Workstation) 35583125a3aSAlessandro Rubini STA2X11-based (e.g. Northville) 3563f4110a4SThomas Gleixner Moorestown MID devices 35706ac8346SIngo Molnar 35806ac8346SIngo Molnar If you have one of these systems, or if you want to build a 35906ac8346SIngo Molnar generic distribution kernel, say Y here - otherwise say N. 3608425091fSRavikiran G Thirumalaiendif 36106ac8346SIngo Molnar 3628425091fSRavikiran G Thirumalaiif X86_64 3638425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 3648425091fSRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 3658425091fSRavikiran G Thirumalai default y 3668425091fSRavikiran G Thirumalai ---help--- 3678425091fSRavikiran G Thirumalai If you disable this option then the kernel will only support 3688425091fSRavikiran G Thirumalai standard PC platforms. (which covers the vast majority of 3698425091fSRavikiran G Thirumalai systems out there.) 3708425091fSRavikiran G Thirumalai 3718425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 3728425091fSRavikiran G Thirumalai for the following (non-PC) 64 bit x86 platforms: 37344b111b5SSteffen Persvold Numascale NumaChip 3748425091fSRavikiran G Thirumalai ScaleMP vSMP 3758425091fSRavikiran G Thirumalai SGI Ultraviolet 3768425091fSRavikiran G Thirumalai 3778425091fSRavikiran G Thirumalai If you have one of these systems, or if you want to build a 3788425091fSRavikiran G Thirumalai generic distribution kernel, say Y here - otherwise say N. 3798425091fSRavikiran G Thirumalaiendif 380c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms 381c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 38244b111b5SSteffen Persvoldconfig X86_NUMACHIP 38344b111b5SSteffen Persvold bool "Numascale NumaChip" 38444b111b5SSteffen Persvold depends on X86_64 38544b111b5SSteffen Persvold depends on X86_EXTENDED_PLATFORM 38644b111b5SSteffen Persvold depends on NUMA 38744b111b5SSteffen Persvold depends on SMP 38844b111b5SSteffen Persvold depends on X86_X2APIC 389f9726bfdSDaniel J Blueman depends on PCI_MMCONFIG 39044b111b5SSteffen Persvold ---help--- 39144b111b5SSteffen Persvold Adds support for Numascale NumaChip large-SMP systems. Needed to 39244b111b5SSteffen Persvold enable more than ~168 cores. 39344b111b5SSteffen Persvold If you don't have one of these, you should say N here. 39403b48632SNick Piggin 3956a48565eSIngo Molnarconfig X86_VSMP 396c5c606d9SRavikiran G Thirumalai bool "ScaleMP vSMP" 3976276a074SBorislav Petkov select HYPERVISOR_GUEST 3986a48565eSIngo Molnar select PARAVIRT 3996a48565eSIngo Molnar depends on X86_64 && PCI 400c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 401ead91d4bSShai Fultheim depends on SMP 4028f9ca475SIngo Molnar ---help--- 4036a48565eSIngo Molnar Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 4046a48565eSIngo Molnar supposed to run on these EM64T-based machines. Only choose this option 4056a48565eSIngo Molnar if you have one of these machines. 4066a48565eSIngo Molnar 407c5c606d9SRavikiran G Thirumalaiconfig X86_UV 408c5c606d9SRavikiran G Thirumalai bool "SGI Ultraviolet" 409c5c606d9SRavikiran G Thirumalai depends on X86_64 410c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 41154c28d29SJack Steiner depends on NUMA 4129d6c26e7SSuresh Siddha depends on X86_X2APIC 413c5c606d9SRavikiran G Thirumalai ---help--- 414c5c606d9SRavikiran G Thirumalai This option is needed in order to support SGI Ultraviolet systems. 415c5c606d9SRavikiran G Thirumalai If you don't have one of these, you should say N here. 416c5c606d9SRavikiran G Thirumalai 417c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms 418c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 419506f1d07SSam Ravnborg 420ddd70cf9SJun Nakajimaconfig X86_GOLDFISH 421ddd70cf9SJun Nakajima bool "Goldfish (Virtual Platform)" 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 837b1ee5441SThomas Gleixner select GENERIC_IRQ_LEGACY_ALLOC_HWIRQ 838506f1d07SSam Ravnborg 83941b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS 84041b9eb26SStefan Assmann bool "Reroute for broken boot IRQs" 84141b9eb26SStefan Assmann depends on X86_IO_APIC 8428f9ca475SIngo Molnar ---help--- 84341b9eb26SStefan Assmann This option enables a workaround that fixes a source of 84441b9eb26SStefan Assmann spurious interrupts. This is recommended when threaded 84541b9eb26SStefan Assmann interrupt handling is used on systems where the generation of 84641b9eb26SStefan Assmann superfluous "boot interrupts" cannot be disabled. 84741b9eb26SStefan Assmann 84841b9eb26SStefan Assmann Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 84941b9eb26SStefan Assmann entry in the chipset's IO-APIC is masked (as, e.g. the RT 85041b9eb26SStefan Assmann kernel does during interrupt handling). On chipsets where this 85141b9eb26SStefan Assmann boot IRQ generation cannot be disabled, this workaround keeps 85241b9eb26SStefan Assmann the original IRQ line masked so that only the equivalent "boot 85341b9eb26SStefan Assmann IRQ" is delivered to the CPUs. The workaround also tells the 85441b9eb26SStefan Assmann kernel to set up the IRQ handler on the boot IRQ line. In this 85541b9eb26SStefan Assmann way only one interrupt is delivered to the kernel. Otherwise 85641b9eb26SStefan Assmann the spurious second interrupt may cause the kernel to bring 85741b9eb26SStefan Assmann down (vital) interrupt lines. 85841b9eb26SStefan Assmann 85941b9eb26SStefan Assmann Only affects "broken" chipsets. Interrupt sharing may be 86041b9eb26SStefan Assmann increased on these systems. 86141b9eb26SStefan Assmann 862506f1d07SSam Ravnborgconfig X86_MCE 863bab9bc65SAndi Kleen bool "Machine Check / overheating reporting" 864e57dbaf7SBorislav Petkov default y 865506f1d07SSam Ravnborg ---help--- 866bab9bc65SAndi Kleen Machine Check support allows the processor to notify the 867bab9bc65SAndi Kleen kernel if it detects a problem (e.g. overheating, data corruption). 868506f1d07SSam Ravnborg The action the kernel takes depends on the severity of the problem, 869bab9bc65SAndi Kleen ranging from warning messages to halting the machine. 8704efc0670SAndi Kleen 871506f1d07SSam Ravnborgconfig X86_MCE_INTEL 8723c2362e6SHarvey Harrison def_bool y 8733c2362e6SHarvey Harrison prompt "Intel MCE features" 874c1ebf835SAndi Kleen depends on X86_MCE && X86_LOCAL_APIC 8758f9ca475SIngo Molnar ---help--- 876506f1d07SSam Ravnborg Additional support for intel specific MCE features such as 877506f1d07SSam Ravnborg the thermal monitor. 878506f1d07SSam Ravnborg 879506f1d07SSam Ravnborgconfig X86_MCE_AMD 8803c2362e6SHarvey Harrison def_bool y 8813c2362e6SHarvey Harrison prompt "AMD MCE features" 882c1ebf835SAndi Kleen depends on X86_MCE && X86_LOCAL_APIC 8838f9ca475SIngo Molnar ---help--- 884506f1d07SSam Ravnborg Additional support for AMD specific MCE features such as 885506f1d07SSam Ravnborg the DRAM Error Threshold. 886506f1d07SSam Ravnborg 8874efc0670SAndi Kleenconfig X86_ANCIENT_MCE 8886fc108a0SJan Beulich bool "Support for old Pentium 5 / WinChip machine checks" 889c31d9633SAndi Kleen depends on X86_32 && X86_MCE 8904efc0670SAndi Kleen ---help--- 8914efc0670SAndi Kleen Include support for machine check handling on old Pentium 5 or WinChip 8925065a706SMasanari Iida systems. These typically need to be enabled explicitly on the command 8934efc0670SAndi Kleen line. 8944efc0670SAndi Kleen 895b2762686SAndi Kleenconfig X86_MCE_THRESHOLD 896b2762686SAndi Kleen depends on X86_MCE_AMD || X86_MCE_INTEL 8976fc108a0SJan Beulich def_bool y 898b2762686SAndi Kleen 899ea149b36SAndi Kleenconfig X86_MCE_INJECT 900c1ebf835SAndi Kleen depends on X86_MCE 901ea149b36SAndi Kleen tristate "Machine check injector support" 902ea149b36SAndi Kleen ---help--- 903ea149b36SAndi Kleen Provide support for injecting machine checks for testing purposes. 904ea149b36SAndi Kleen If you don't know what a machine check is and you don't do kernel 905ea149b36SAndi Kleen QA it is safe to say n. 906ea149b36SAndi Kleen 9074efc0670SAndi Kleenconfig X86_THERMAL_VECTOR 9084efc0670SAndi Kleen def_bool y 9095bb38adcSAndi Kleen depends on X86_MCE_INTEL 9104efc0670SAndi Kleen 911506f1d07SSam Ravnborgconfig VM86 9126a108a14SDavid Rientjes bool "Enable VM86 support" if EXPERT 913506f1d07SSam Ravnborg default y 914506f1d07SSam Ravnborg depends on X86_32 9158f9ca475SIngo Molnar ---help--- 91634273f41SH. Peter Anvin This option is required by programs like DOSEMU to run 91734273f41SH. Peter Anvin 16-bit real mode legacy code on x86 processors. It also may 91834273f41SH. Peter Anvin be needed by software like XFree86 to initialize some video 91934273f41SH. Peter Anvin cards via BIOS. Disabling this option saves about 6K. 92034273f41SH. Peter Anvin 92134273f41SH. Peter Anvinconfig X86_16BIT 92234273f41SH. Peter Anvin bool "Enable support for 16-bit segments" if EXPERT 92334273f41SH. Peter Anvin default y 92434273f41SH. Peter Anvin ---help--- 92534273f41SH. Peter Anvin This option is required by programs like Wine to run 16-bit 92634273f41SH. Peter Anvin protected mode legacy code on x86 processors. Disabling 92734273f41SH. Peter Anvin this option saves about 300 bytes on i386, or around 6K text 92834273f41SH. Peter Anvin plus 16K runtime memory on x86-64, 92934273f41SH. Peter Anvin 93034273f41SH. Peter Anvinconfig X86_ESPFIX32 93134273f41SH. Peter Anvin def_bool y 93234273f41SH. Peter Anvin depends on X86_16BIT && X86_32 933506f1d07SSam Ravnborg 934197725deSH. Peter Anvinconfig X86_ESPFIX64 935197725deSH. Peter Anvin def_bool y 93634273f41SH. Peter Anvin depends on X86_16BIT && X86_64 937506f1d07SSam Ravnborg 938506f1d07SSam Ravnborgconfig TOSHIBA 939506f1d07SSam Ravnborg tristate "Toshiba Laptop support" 940506f1d07SSam Ravnborg depends on X86_32 941506f1d07SSam Ravnborg ---help--- 942506f1d07SSam Ravnborg This adds a driver to safely access the System Management Mode of 943506f1d07SSam Ravnborg the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 944506f1d07SSam Ravnborg not work on models with a Phoenix BIOS. The System Management Mode 945506f1d07SSam Ravnborg is used to set the BIOS and power saving options on Toshiba portables. 946506f1d07SSam Ravnborg 947506f1d07SSam Ravnborg For information on utilities to make use of this driver see the 948506f1d07SSam Ravnborg Toshiba Linux utilities web site at: 949506f1d07SSam Ravnborg <http://www.buzzard.org.uk/toshiba/>. 950506f1d07SSam Ravnborg 951506f1d07SSam Ravnborg Say Y if you intend to run this kernel on a Toshiba portable. 952506f1d07SSam Ravnborg Say N otherwise. 953506f1d07SSam Ravnborg 954506f1d07SSam Ravnborgconfig I8K 955506f1d07SSam Ravnborg tristate "Dell laptop support" 956949a9d70SJean Delvare select HWMON 957506f1d07SSam Ravnborg ---help--- 958506f1d07SSam Ravnborg This adds a driver to safely access the System Management Mode 959506f1d07SSam Ravnborg of the CPU on the Dell Inspiron 8000. The System Management Mode 960506f1d07SSam Ravnborg is used to read cpu temperature and cooling fan status and to 961506f1d07SSam Ravnborg control the fans on the I8K portables. 962506f1d07SSam Ravnborg 963506f1d07SSam Ravnborg This driver has been tested only on the Inspiron 8000 but it may 964506f1d07SSam Ravnborg also work with other Dell laptops. You can force loading on other 965506f1d07SSam Ravnborg models by passing the parameter `force=1' to the module. Use at 966506f1d07SSam Ravnborg your own risk. 967506f1d07SSam Ravnborg 968506f1d07SSam Ravnborg For information on utilities to make use of this driver see the 969506f1d07SSam Ravnborg I8K Linux utilities web site at: 970506f1d07SSam Ravnborg <http://people.debian.org/~dz/i8k/> 971506f1d07SSam Ravnborg 972506f1d07SSam Ravnborg Say Y if you intend to run this kernel on a Dell Inspiron 8000. 973506f1d07SSam Ravnborg Say N otherwise. 974506f1d07SSam Ravnborg 975506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS 9769ba16087SJan Beulich bool "Enable X86 board specific fixups for reboot" 9779ba16087SJan Beulich depends on X86_32 978506f1d07SSam Ravnborg ---help--- 979506f1d07SSam Ravnborg This enables chipset and/or board specific fixups to be done 980506f1d07SSam Ravnborg in order to get reboot to work correctly. This is only needed on 981506f1d07SSam Ravnborg some combinations of hardware and BIOS. The symptom, for which 982506f1d07SSam Ravnborg this config is intended, is when reboot ends with a stalled/hung 983506f1d07SSam Ravnborg system. 984506f1d07SSam Ravnborg 985506f1d07SSam Ravnborg Currently, the only fixup is for the Geode machines using 9865e3a77e9SFlorian Fainelli CS5530A and CS5536 chipsets and the RDC R-321x SoC. 987506f1d07SSam Ravnborg 988506f1d07SSam Ravnborg Say Y if you want to enable the fixup. Currently, it's safe to 989506f1d07SSam Ravnborg enable this option even if you don't need it. 990506f1d07SSam Ravnborg Say N otherwise. 991506f1d07SSam Ravnborg 992506f1d07SSam Ravnborgconfig MICROCODE 993e43f6e67SBorislav Petkov tristate "CPU microcode loading support" 99480030e3dSBorislav Petkov depends on CPU_SUP_AMD || CPU_SUP_INTEL 995506f1d07SSam Ravnborg select FW_LOADER 996506f1d07SSam Ravnborg ---help--- 997e43f6e67SBorislav Petkov 998506f1d07SSam Ravnborg If you say Y here, you will be able to update the microcode on 99980cc9f10SPeter Oruba certain Intel and AMD processors. The Intel support is for the 1000e43f6e67SBorislav Petkov IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, 1001e43f6e67SBorislav Petkov Xeon etc. The AMD support is for families 0x10 and later. You will 1002e43f6e67SBorislav Petkov obviously need the actual microcode binary data itself which is not 1003e43f6e67SBorislav Petkov shipped with the Linux kernel. 1004506f1d07SSam Ravnborg 10058d86f390SPeter Oruba This option selects the general module only, you need to select 10068d86f390SPeter Oruba at least one vendor specific module as well. 1007506f1d07SSam Ravnborg 1008e43f6e67SBorislav Petkov To compile this driver as a module, choose M here: the module 1009e43f6e67SBorislav Petkov will be called microcode. 1010506f1d07SSam Ravnborg 10118d86f390SPeter Orubaconfig MICROCODE_INTEL 1012e43f6e67SBorislav Petkov bool "Intel microcode loading support" 10138d86f390SPeter Oruba depends on MICROCODE 10148d86f390SPeter Oruba default MICROCODE 10158d86f390SPeter Oruba select FW_LOADER 10168f9ca475SIngo Molnar ---help--- 10178d86f390SPeter Oruba This options enables microcode patch loading support for Intel 10188d86f390SPeter Oruba processors. 10198d86f390SPeter Oruba 1020b8989db9SAlan For the current Intel microcode data package go to 1021b8989db9SAlan <https://downloadcenter.intel.com> and search for 1022b8989db9SAlan 'Linux Processor Microcode Data File'. 10238d86f390SPeter Oruba 102480cc9f10SPeter Orubaconfig MICROCODE_AMD 1025e43f6e67SBorislav Petkov bool "AMD microcode loading support" 102680cc9f10SPeter Oruba depends on MICROCODE 102780cc9f10SPeter Oruba select FW_LOADER 10288f9ca475SIngo Molnar ---help--- 102980cc9f10SPeter Oruba If you select this option, microcode patch loading support for AMD 103080cc9f10SPeter Oruba processors will be enabled. 103180cc9f10SPeter Oruba 1032506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE 10333c2362e6SHarvey Harrison def_bool y 1034506f1d07SSam Ravnborg depends on MICROCODE 1035506f1d07SSam Ravnborg 1036da76f64eSFenghua Yuconfig MICROCODE_INTEL_EARLY 1037757885e9SJacob Shin def_bool n 1038757885e9SJacob Shin 1039757885e9SJacob Shinconfig MICROCODE_AMD_EARLY 1040757885e9SJacob Shin def_bool n 1041757885e9SJacob Shin 1042757885e9SJacob Shinconfig MICROCODE_EARLY 1043da76f64eSFenghua Yu bool "Early load microcode" 10446b3389acSJacob Shin depends on MICROCODE=y && BLK_DEV_INITRD 1045757885e9SJacob Shin select MICROCODE_INTEL_EARLY if MICROCODE_INTEL 1046757885e9SJacob Shin select MICROCODE_AMD_EARLY if MICROCODE_AMD 1047da76f64eSFenghua Yu default y 1048da76f64eSFenghua Yu help 1049da76f64eSFenghua Yu This option provides functionality to read additional microcode data 1050da76f64eSFenghua Yu at the beginning of initrd image. The data tells kernel to load 1051da76f64eSFenghua Yu microcode to CPU's as early as possible. No functional change if no 1052da76f64eSFenghua Yu microcode data is glued to the initrd, therefore it's safe to say Y. 1053da76f64eSFenghua Yu 1054506f1d07SSam Ravnborgconfig X86_MSR 1055506f1d07SSam Ravnborg tristate "/dev/cpu/*/msr - Model-specific register support" 10568f9ca475SIngo Molnar ---help--- 1057506f1d07SSam Ravnborg This device gives privileged processes access to the x86 1058506f1d07SSam Ravnborg Model-Specific Registers (MSRs). It is a character device with 1059506f1d07SSam Ravnborg major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1060506f1d07SSam Ravnborg MSR accesses are directed to a specific CPU on multi-processor 1061506f1d07SSam Ravnborg systems. 1062506f1d07SSam Ravnborg 1063506f1d07SSam Ravnborgconfig X86_CPUID 1064506f1d07SSam Ravnborg tristate "/dev/cpu/*/cpuid - CPU information support" 10658f9ca475SIngo Molnar ---help--- 1066506f1d07SSam Ravnborg This device gives processes access to the x86 CPUID instruction to 1067506f1d07SSam Ravnborg be executed on a specific processor. It is a character device 1068506f1d07SSam Ravnborg with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1069506f1d07SSam Ravnborg /dev/cpu/31/cpuid. 1070506f1d07SSam Ravnborg 1071506f1d07SSam Ravnborgchoice 1072506f1d07SSam Ravnborg prompt "High Memory Support" 10736fc108a0SJan Beulich default HIGHMEM4G 1074506f1d07SSam Ravnborg depends on X86_32 1075506f1d07SSam Ravnborg 1076506f1d07SSam Ravnborgconfig NOHIGHMEM 1077506f1d07SSam Ravnborg bool "off" 1078506f1d07SSam Ravnborg ---help--- 1079506f1d07SSam Ravnborg Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1080506f1d07SSam Ravnborg However, the address space of 32-bit x86 processors is only 4 1081506f1d07SSam Ravnborg Gigabytes large. That means that, if you have a large amount of 1082506f1d07SSam Ravnborg physical memory, not all of it can be "permanently mapped" by the 1083506f1d07SSam Ravnborg kernel. The physical memory that's not permanently mapped is called 1084506f1d07SSam Ravnborg "high memory". 1085506f1d07SSam Ravnborg 1086506f1d07SSam Ravnborg If you are compiling a kernel which will never run on a machine with 1087506f1d07SSam Ravnborg more than 1 Gigabyte total physical RAM, answer "off" here (default 1088506f1d07SSam Ravnborg choice and suitable for most users). This will result in a "3GB/1GB" 1089506f1d07SSam Ravnborg split: 3GB are mapped so that each process sees a 3GB virtual memory 1090506f1d07SSam Ravnborg space and the remaining part of the 4GB virtual memory space is used 1091506f1d07SSam Ravnborg by the kernel to permanently map as much physical memory as 1092506f1d07SSam Ravnborg possible. 1093506f1d07SSam Ravnborg 1094506f1d07SSam Ravnborg If the machine has between 1 and 4 Gigabytes physical RAM, then 1095506f1d07SSam Ravnborg answer "4GB" here. 1096506f1d07SSam Ravnborg 1097506f1d07SSam Ravnborg If more than 4 Gigabytes is used then answer "64GB" here. This 1098506f1d07SSam Ravnborg selection turns Intel PAE (Physical Address Extension) mode on. 1099506f1d07SSam Ravnborg PAE implements 3-level paging on IA32 processors. PAE is fully 1100506f1d07SSam Ravnborg supported by Linux, PAE mode is implemented on all recent Intel 1101506f1d07SSam Ravnborg processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1102506f1d07SSam Ravnborg then the kernel will not boot on CPUs that don't support PAE! 1103506f1d07SSam Ravnborg 1104506f1d07SSam Ravnborg The actual amount of total physical memory will either be 1105506f1d07SSam Ravnborg auto detected or can be forced by using a kernel command line option 1106506f1d07SSam Ravnborg such as "mem=256M". (Try "man bootparam" or see the documentation of 1107506f1d07SSam Ravnborg your boot loader (lilo or loadlin) about how to pass options to the 1108506f1d07SSam Ravnborg kernel at boot time.) 1109506f1d07SSam Ravnborg 1110506f1d07SSam Ravnborg If unsure, say "off". 1111506f1d07SSam Ravnborg 1112506f1d07SSam Ravnborgconfig HIGHMEM4G 1113506f1d07SSam Ravnborg bool "4GB" 11148f9ca475SIngo Molnar ---help--- 1115506f1d07SSam Ravnborg Select this if you have a 32-bit processor and between 1 and 4 1116506f1d07SSam Ravnborg gigabytes of physical RAM. 1117506f1d07SSam Ravnborg 1118506f1d07SSam Ravnborgconfig HIGHMEM64G 1119506f1d07SSam Ravnborg bool "64GB" 1120eb068e78SH. Peter Anvin depends on !M486 1121506f1d07SSam Ravnborg select X86_PAE 11228f9ca475SIngo Molnar ---help--- 1123506f1d07SSam Ravnborg Select this if you have a 32-bit processor and more than 4 1124506f1d07SSam Ravnborg gigabytes of physical RAM. 1125506f1d07SSam Ravnborg 1126506f1d07SSam Ravnborgendchoice 1127506f1d07SSam Ravnborg 1128506f1d07SSam Ravnborgchoice 11296a108a14SDavid Rientjes prompt "Memory split" if EXPERT 1130506f1d07SSam Ravnborg default VMSPLIT_3G 1131506f1d07SSam Ravnborg depends on X86_32 11328f9ca475SIngo Molnar ---help--- 1133506f1d07SSam Ravnborg Select the desired split between kernel and user memory. 1134506f1d07SSam Ravnborg 1135506f1d07SSam Ravnborg If the address range available to the kernel is less than the 1136506f1d07SSam Ravnborg physical memory installed, the remaining memory will be available 1137506f1d07SSam Ravnborg as "high memory". Accessing high memory is a little more costly 1138506f1d07SSam Ravnborg than low memory, as it needs to be mapped into the kernel first. 1139506f1d07SSam Ravnborg Note that increasing the kernel address space limits the range 1140506f1d07SSam Ravnborg available to user programs, making the address space there 1141506f1d07SSam Ravnborg tighter. Selecting anything other than the default 3G/1G split 1142506f1d07SSam Ravnborg will also likely make your kernel incompatible with binary-only 1143506f1d07SSam Ravnborg kernel modules. 1144506f1d07SSam Ravnborg 1145506f1d07SSam Ravnborg If you are not absolutely sure what you are doing, leave this 1146506f1d07SSam Ravnborg option alone! 1147506f1d07SSam Ravnborg 1148506f1d07SSam Ravnborg config VMSPLIT_3G 1149506f1d07SSam Ravnborg bool "3G/1G user/kernel split" 1150506f1d07SSam Ravnborg config VMSPLIT_3G_OPT 1151506f1d07SSam Ravnborg depends on !X86_PAE 1152506f1d07SSam Ravnborg bool "3G/1G user/kernel split (for full 1G low memory)" 1153506f1d07SSam Ravnborg config VMSPLIT_2G 1154506f1d07SSam Ravnborg bool "2G/2G user/kernel split" 1155506f1d07SSam Ravnborg config VMSPLIT_2G_OPT 1156506f1d07SSam Ravnborg depends on !X86_PAE 1157506f1d07SSam Ravnborg bool "2G/2G user/kernel split (for full 2G low memory)" 1158506f1d07SSam Ravnborg config VMSPLIT_1G 1159506f1d07SSam Ravnborg bool "1G/3G user/kernel split" 1160506f1d07SSam Ravnborgendchoice 1161506f1d07SSam Ravnborg 1162506f1d07SSam Ravnborgconfig PAGE_OFFSET 1163506f1d07SSam Ravnborg hex 1164506f1d07SSam Ravnborg default 0xB0000000 if VMSPLIT_3G_OPT 1165506f1d07SSam Ravnborg default 0x80000000 if VMSPLIT_2G 1166506f1d07SSam Ravnborg default 0x78000000 if VMSPLIT_2G_OPT 1167506f1d07SSam Ravnborg default 0x40000000 if VMSPLIT_1G 1168506f1d07SSam Ravnborg default 0xC0000000 1169506f1d07SSam Ravnborg depends on X86_32 1170506f1d07SSam Ravnborg 1171506f1d07SSam Ravnborgconfig HIGHMEM 11723c2362e6SHarvey Harrison def_bool y 1173506f1d07SSam Ravnborg depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1174506f1d07SSam Ravnborg 1175506f1d07SSam Ravnborgconfig X86_PAE 11769ba16087SJan Beulich bool "PAE (Physical Address Extension) Support" 1177506f1d07SSam Ravnborg depends on X86_32 && !HIGHMEM4G 11788f9ca475SIngo Molnar ---help--- 1179506f1d07SSam Ravnborg PAE is required for NX support, and furthermore enables 1180506f1d07SSam Ravnborg larger swapspace support for non-overcommit purposes. It 1181506f1d07SSam Ravnborg has the cost of more pagetable lookup overhead, and also 1182506f1d07SSam Ravnborg consumes more pagetable space per process. 1183506f1d07SSam Ravnborg 1184600715dcSJeremy Fitzhardingeconfig ARCH_PHYS_ADDR_T_64BIT 11853120e25eSJan Beulich def_bool y 11863120e25eSJan Beulich depends on X86_64 || X86_PAE 1187600715dcSJeremy Fitzhardinge 118866f2b061SFUJITA Tomonoriconfig ARCH_DMA_ADDR_T_64BIT 11893120e25eSJan Beulich def_bool y 11903120e25eSJan Beulich depends on X86_64 || HIGHMEM64G 119166f2b061SFUJITA Tomonori 11929e899816SNick Pigginconfig DIRECT_GBPAGES 11936a108a14SDavid Rientjes bool "Enable 1GB pages for kernel pagetables" if EXPERT 11949e899816SNick Piggin default y 11959e899816SNick Piggin depends on X86_64 11968f9ca475SIngo Molnar ---help--- 11979e899816SNick Piggin Allow the kernel linear mapping to use 1GB pages on CPUs that 11989e899816SNick Piggin support it. This can improve the kernel's performance a tiny bit by 11999e899816SNick Piggin reducing TLB pressure. If in doubt, say "Y". 12009e899816SNick Piggin 1201506f1d07SSam Ravnborg# Common NUMA Features 1202506f1d07SSam Ravnborgconfig NUMA 1203fd51b2d7SKOSAKI Motohiro bool "Numa Memory Allocation and Scheduler Support" 1204506f1d07SSam Ravnborg depends on SMP 1205b5660ba7SH. Peter Anvin depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1206b5660ba7SH. Peter Anvin default y if X86_BIGSMP 12078f9ca475SIngo Molnar ---help--- 1208506f1d07SSam Ravnborg Enable NUMA (Non Uniform Memory Access) support. 1209fd51b2d7SKOSAKI Motohiro 1210506f1d07SSam Ravnborg The kernel will try to allocate memory used by a CPU on the 1211506f1d07SSam Ravnborg local memory controller of the CPU and add some more 1212506f1d07SSam Ravnborg NUMA awareness to the kernel. 1213506f1d07SSam Ravnborg 1214c280ea5eSIngo Molnar For 64-bit this is recommended if the system is Intel Core i7 1215fd51b2d7SKOSAKI Motohiro (or later), AMD Opteron, or EM64T NUMA. 1216fd51b2d7SKOSAKI Motohiro 1217b5660ba7SH. Peter Anvin For 32-bit this is only needed if you boot a 32-bit 12187cf6c945SDavid Rientjes kernel on a 64-bit NUMA platform. 1219fd51b2d7SKOSAKI Motohiro 1220fd51b2d7SKOSAKI Motohiro Otherwise, you should say N. 1221506f1d07SSam Ravnborg 1222eec1d4faSHans Rosenfeldconfig AMD_NUMA 12233c2362e6SHarvey Harrison def_bool y 12243c2362e6SHarvey Harrison prompt "Old style AMD Opteron NUMA detection" 12255da0ef9aSTejun Heo depends on X86_64 && NUMA && PCI 12268f9ca475SIngo Molnar ---help--- 1227eec1d4faSHans Rosenfeld Enable AMD NUMA node topology detection. You should say Y here if 1228eec1d4faSHans Rosenfeld you have a multi processor AMD system. This uses an old method to 1229eec1d4faSHans Rosenfeld read the NUMA configuration directly from the builtin Northbridge 1230eec1d4faSHans Rosenfeld of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1231eec1d4faSHans Rosenfeld which also takes priority if both are compiled in. 1232506f1d07SSam Ravnborg 1233506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA 12343c2362e6SHarvey Harrison def_bool y 12353c2362e6SHarvey Harrison prompt "ACPI NUMA detection" 1236506f1d07SSam Ravnborg depends on X86_64 && NUMA && ACPI && PCI 1237506f1d07SSam Ravnborg select ACPI_NUMA 12388f9ca475SIngo Molnar ---help--- 1239506f1d07SSam Ravnborg Enable ACPI SRAT based node topology detection. 1240506f1d07SSam Ravnborg 12416ec6e0d9SSuresh Siddha# Some NUMA nodes have memory ranges that span 12426ec6e0d9SSuresh Siddha# other nodes. Even though a pfn is valid and 12436ec6e0d9SSuresh Siddha# between a node's start and end pfns, it may not 12446ec6e0d9SSuresh Siddha# reside on that node. See memmap_init_zone() 12456ec6e0d9SSuresh Siddha# for details. 12466ec6e0d9SSuresh Siddhaconfig NODES_SPAN_OTHER_NODES 12476ec6e0d9SSuresh Siddha def_bool y 12486ec6e0d9SSuresh Siddha depends on X86_64_ACPI_NUMA 12496ec6e0d9SSuresh Siddha 1250506f1d07SSam Ravnborgconfig NUMA_EMU 1251506f1d07SSam Ravnborg bool "NUMA emulation" 12521b7e03efSTejun Heo depends on NUMA 12538f9ca475SIngo Molnar ---help--- 1254506f1d07SSam Ravnborg Enable NUMA emulation. A flat machine will be split 1255506f1d07SSam Ravnborg into virtual nodes when booted with "numa=fake=N", where N is the 1256506f1d07SSam Ravnborg number of nodes. This is only useful for debugging. 1257506f1d07SSam Ravnborg 1258506f1d07SSam Ravnborgconfig NODES_SHIFT 1259d25e26b6SLinus Torvalds int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 126051591e31SDavid Rientjes range 1 10 126151591e31SDavid Rientjes default "10" if MAXSMP 1262506f1d07SSam Ravnborg default "6" if X86_64 1263506f1d07SSam Ravnborg default "3" 1264506f1d07SSam Ravnborg depends on NEED_MULTIPLE_NODES 12658f9ca475SIngo Molnar ---help--- 12661184dc2fSMike Travis Specify the maximum number of NUMA Nodes available on the target 1267692105b8SMatt LaPlante system. Increases memory reserved to accommodate various tables. 1268506f1d07SSam Ravnborg 1269506f1d07SSam Ravnborgconfig ARCH_HAVE_MEMORY_PRESENT 12703c2362e6SHarvey Harrison def_bool y 1271506f1d07SSam Ravnborg depends on X86_32 && DISCONTIGMEM 1272506f1d07SSam Ravnborg 1273506f1d07SSam Ravnborgconfig NEED_NODE_MEMMAP_SIZE 12743c2362e6SHarvey Harrison def_bool y 1275506f1d07SSam Ravnborg depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1276506f1d07SSam Ravnborg 1277506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE 1278506f1d07SSam Ravnborg def_bool y 12793b16651fSTejun Heo depends on X86_32 && !NUMA 1280506f1d07SSam Ravnborg 1281506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_ENABLE 1282506f1d07SSam Ravnborg def_bool y 1283b263295dSChristoph Lameter depends on NUMA && X86_32 1284506f1d07SSam Ravnborg 1285506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_DEFAULT 1286506f1d07SSam Ravnborg def_bool y 1287b263295dSChristoph Lameter depends on NUMA && X86_32 1288b263295dSChristoph Lameter 1289506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE 1290506f1d07SSam Ravnborg def_bool y 12916ea30386SKees Cook depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1292506f1d07SSam Ravnborg select SPARSEMEM_STATIC if X86_32 1293506f1d07SSam Ravnborg select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1294506f1d07SSam Ravnborg 12953b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT 12963b16651fSTejun Heo def_bool y 12973b16651fSTejun Heo depends on X86_64 12983b16651fSTejun Heo 1299506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL 1300506f1d07SSam Ravnborg def_bool y 1301b263295dSChristoph Lameter depends on ARCH_SPARSEMEM_ENABLE 1302506f1d07SSam Ravnborg 1303506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE 1304a0842b70SToshi Kani bool "Enable sysfs memory/probe interface" 13053120e25eSJan Beulich depends on X86_64 && MEMORY_HOTPLUG 1306a0842b70SToshi Kani help 1307a0842b70SToshi Kani This option enables a sysfs memory/probe interface for testing. 1308a0842b70SToshi Kani See Documentation/memory-hotplug.txt for more information. 1309a0842b70SToshi Kani If you are unsure how to answer this question, answer N. 1310506f1d07SSam Ravnborg 13113b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT 13123b16651fSTejun Heo def_bool y 13133b16651fSTejun Heo depends on X86_64 && PROC_KCORE 13143b16651fSTejun Heo 1315a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE 1316a29815a3SAvi Kivity hex 1317a29815a3SAvi Kivity default 0 if X86_32 1318a29815a3SAvi Kivity default 0xdead000000000000 if X86_64 1319a29815a3SAvi Kivity 1320506f1d07SSam Ravnborgsource "mm/Kconfig" 1321506f1d07SSam Ravnborg 1322506f1d07SSam Ravnborgconfig HIGHPTE 1323506f1d07SSam Ravnborg bool "Allocate 3rd-level pagetables from highmem" 13246fc108a0SJan Beulich depends on HIGHMEM 13258f9ca475SIngo Molnar ---help--- 1326506f1d07SSam Ravnborg The VM uses one page table entry for each page of physical memory. 1327506f1d07SSam Ravnborg For systems with a lot of RAM, this can be wasteful of precious 1328506f1d07SSam Ravnborg low memory. Setting this option will put user-space page table 1329506f1d07SSam Ravnborg entries in high memory. 1330506f1d07SSam Ravnborg 13319f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION 13329f077871SJeremy Fitzhardinge bool "Check for low memory corruption" 13338f9ca475SIngo Molnar ---help--- 13349f077871SJeremy Fitzhardinge Periodically check for memory corruption in low memory, which 13359f077871SJeremy Fitzhardinge is suspected to be caused by BIOS. Even when enabled in the 13369f077871SJeremy Fitzhardinge configuration, it is disabled at runtime. Enable it by 13379f077871SJeremy Fitzhardinge setting "memory_corruption_check=1" on the kernel command 13389f077871SJeremy Fitzhardinge line. By default it scans the low 64k of memory every 60 13399f077871SJeremy Fitzhardinge seconds; see the memory_corruption_check_size and 13409f077871SJeremy Fitzhardinge memory_corruption_check_period parameters in 13419f077871SJeremy Fitzhardinge Documentation/kernel-parameters.txt to adjust this. 13429f077871SJeremy Fitzhardinge 13439f077871SJeremy Fitzhardinge When enabled with the default parameters, this option has 13449f077871SJeremy Fitzhardinge almost no overhead, as it reserves a relatively small amount 13459f077871SJeremy Fitzhardinge of memory and scans it infrequently. It both detects corruption 13469f077871SJeremy Fitzhardinge and prevents it from affecting the running system. 13479f077871SJeremy Fitzhardinge 13489f077871SJeremy Fitzhardinge It is, however, intended as a diagnostic tool; if repeatable 13499f077871SJeremy Fitzhardinge BIOS-originated corruption always affects the same memory, 13509f077871SJeremy Fitzhardinge you can use memmap= to prevent the kernel from using that 13519f077871SJeremy Fitzhardinge memory. 13529f077871SJeremy Fitzhardinge 1353c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1354c885df50SJeremy Fitzhardinge bool "Set the default setting of memory_corruption_check" 1355c885df50SJeremy Fitzhardinge depends on X86_CHECK_BIOS_CORRUPTION 1356c885df50SJeremy Fitzhardinge default y 13578f9ca475SIngo Molnar ---help--- 1358c885df50SJeremy Fitzhardinge Set whether the default state of memory_corruption_check is 1359c885df50SJeremy Fitzhardinge on or off. 1360c885df50SJeremy Fitzhardinge 13619ea77bdbSH. Peter Anvinconfig X86_RESERVE_LOW 1362d0cd7425SH. Peter Anvin int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1363d0cd7425SH. Peter Anvin default 64 1364d0cd7425SH. Peter Anvin range 4 640 13658f9ca475SIngo Molnar ---help--- 1366d0cd7425SH. Peter Anvin Specify the amount of low memory to reserve for the BIOS. 1367fc381519SIngo Molnar 1368d0cd7425SH. Peter Anvin The first page contains BIOS data structures that the kernel 1369d0cd7425SH. Peter Anvin must not use, so that page must always be reserved. 1370fc381519SIngo Molnar 1371d0cd7425SH. Peter Anvin By default we reserve the first 64K of physical RAM, as a 1372d0cd7425SH. Peter Anvin number of BIOSes are known to corrupt that memory range 1373d0cd7425SH. Peter Anvin during events such as suspend/resume or monitor cable 1374d0cd7425SH. Peter Anvin insertion, so it must not be used by the kernel. 1375fc381519SIngo Molnar 1376d0cd7425SH. Peter Anvin You can set this to 4 if you are absolutely sure that you 1377d0cd7425SH. Peter Anvin trust the BIOS to get all its memory reservations and usages 1378d0cd7425SH. Peter Anvin right. If you know your BIOS have problems beyond the 1379d0cd7425SH. Peter Anvin default 64K area, you can set this to 640 to avoid using the 1380d0cd7425SH. Peter Anvin entire low memory range. 1381d0cd7425SH. Peter Anvin 1382d0cd7425SH. Peter Anvin If you have doubts about the BIOS (e.g. suspend/resume does 1383d0cd7425SH. Peter Anvin not work or there's kernel crashes after certain hardware 1384d0cd7425SH. Peter Anvin hotplug events) then you might want to enable 1385d0cd7425SH. Peter Anvin X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1386d0cd7425SH. Peter Anvin typical corruption patterns. 1387d0cd7425SH. Peter Anvin 1388d0cd7425SH. Peter Anvin Leave this to the default value of 64 if you are unsure. 1389fc381519SIngo Molnar 1390506f1d07SSam Ravnborgconfig MATH_EMULATION 1391506f1d07SSam Ravnborg bool 1392506f1d07SSam Ravnborg prompt "Math emulation" if X86_32 1393506f1d07SSam Ravnborg ---help--- 1394506f1d07SSam Ravnborg Linux can emulate a math coprocessor (used for floating point 1395506f1d07SSam Ravnborg operations) if you don't have one. 486DX and Pentium processors have 1396506f1d07SSam Ravnborg a math coprocessor built in, 486SX and 386 do not, unless you added 1397506f1d07SSam Ravnborg a 487DX or 387, respectively. (The messages during boot time can 1398506f1d07SSam Ravnborg give you some hints here ["man dmesg"].) Everyone needs either a 1399506f1d07SSam Ravnborg coprocessor or this emulation. 1400506f1d07SSam Ravnborg 1401506f1d07SSam Ravnborg If you don't have a math coprocessor, you need to say Y here; if you 1402506f1d07SSam Ravnborg say Y here even though you have a coprocessor, the coprocessor will 1403506f1d07SSam Ravnborg be used nevertheless. (This behavior can be changed with the kernel 1404506f1d07SSam Ravnborg command line option "no387", which comes handy if your coprocessor 1405506f1d07SSam Ravnborg is broken. Try "man bootparam" or see the documentation of your boot 1406506f1d07SSam Ravnborg loader (lilo or loadlin) about how to pass options to the kernel at 1407506f1d07SSam Ravnborg boot time.) This means that it is a good idea to say Y here if you 1408506f1d07SSam Ravnborg intend to use this kernel on different machines. 1409506f1d07SSam Ravnborg 1410506f1d07SSam Ravnborg More information about the internals of the Linux math coprocessor 1411506f1d07SSam Ravnborg emulation can be found in <file:arch/x86/math-emu/README>. 1412506f1d07SSam Ravnborg 1413506f1d07SSam Ravnborg If you are not sure, say Y; apart from resulting in a 66 KB bigger 1414506f1d07SSam Ravnborg kernel, it won't hurt. 1415506f1d07SSam Ravnborg 1416506f1d07SSam Ravnborgconfig MTRR 14176fc108a0SJan Beulich def_bool y 14186a108a14SDavid Rientjes prompt "MTRR (Memory Type Range Register) support" if EXPERT 1419506f1d07SSam Ravnborg ---help--- 1420506f1d07SSam Ravnborg On Intel P6 family processors (Pentium Pro, Pentium II and later) 1421506f1d07SSam Ravnborg the Memory Type Range Registers (MTRRs) may be used to control 1422506f1d07SSam Ravnborg processor access to memory ranges. This is most useful if you have 1423506f1d07SSam Ravnborg a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1424506f1d07SSam Ravnborg allows bus write transfers to be combined into a larger transfer 1425506f1d07SSam Ravnborg before bursting over the PCI/AGP bus. This can increase performance 1426506f1d07SSam Ravnborg of image write operations 2.5 times or more. Saying Y here creates a 1427506f1d07SSam Ravnborg /proc/mtrr file which may be used to manipulate your processor's 1428506f1d07SSam Ravnborg MTRRs. Typically the X server should use this. 1429506f1d07SSam Ravnborg 1430506f1d07SSam Ravnborg This code has a reasonably generic interface so that similar 1431506f1d07SSam Ravnborg control registers on other processors can be easily supported 1432506f1d07SSam Ravnborg as well: 1433506f1d07SSam Ravnborg 1434506f1d07SSam Ravnborg The Cyrix 6x86, 6x86MX and M II processors have Address Range 1435506f1d07SSam Ravnborg Registers (ARRs) which provide a similar functionality to MTRRs. For 1436506f1d07SSam Ravnborg these, the ARRs are used to emulate the MTRRs. 1437506f1d07SSam Ravnborg The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1438506f1d07SSam Ravnborg MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1439506f1d07SSam Ravnborg write-combining. All of these processors are supported by this code 1440506f1d07SSam Ravnborg and it makes sense to say Y here if you have one of them. 1441506f1d07SSam Ravnborg 1442506f1d07SSam Ravnborg Saying Y here also fixes a problem with buggy SMP BIOSes which only 1443506f1d07SSam Ravnborg set the MTRRs for the boot CPU and not for the secondary CPUs. This 1444506f1d07SSam Ravnborg can lead to all sorts of problems, so it's good to say Y here. 1445506f1d07SSam Ravnborg 1446506f1d07SSam Ravnborg You can safely say Y even if your machine doesn't have MTRRs, you'll 1447506f1d07SSam Ravnborg just add about 9 KB to your kernel. 1448506f1d07SSam Ravnborg 14497225e751SRandy Dunlap See <file:Documentation/x86/mtrr.txt> for more information. 1450506f1d07SSam Ravnborg 145195ffa243SYinghai Luconfig MTRR_SANITIZER 14522ffb3501SYinghai Lu def_bool y 145395ffa243SYinghai Lu prompt "MTRR cleanup support" 145495ffa243SYinghai Lu depends on MTRR 14558f9ca475SIngo Molnar ---help--- 1456aba3728cSThomas Gleixner Convert MTRR layout from continuous to discrete, so X drivers can 1457aba3728cSThomas Gleixner add writeback entries. 145895ffa243SYinghai Lu 1459aba3728cSThomas Gleixner Can be disabled with disable_mtrr_cleanup on the kernel command line. 1460692105b8SMatt LaPlante The largest mtrr entry size for a continuous block can be set with 1461aba3728cSThomas Gleixner mtrr_chunk_size. 146295ffa243SYinghai Lu 14632ffb3501SYinghai Lu If unsure, say Y. 146495ffa243SYinghai Lu 146595ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT 1466f5098d62SYinghai Lu int "MTRR cleanup enable value (0-1)" 1467f5098d62SYinghai Lu range 0 1 1468f5098d62SYinghai Lu default "0" 146995ffa243SYinghai Lu depends on MTRR_SANITIZER 14708f9ca475SIngo Molnar ---help--- 1471f5098d62SYinghai Lu Enable mtrr cleanup default value 147295ffa243SYinghai Lu 147312031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 147412031a62SYinghai Lu int "MTRR cleanup spare reg num (0-7)" 147512031a62SYinghai Lu range 0 7 147612031a62SYinghai Lu default "1" 147712031a62SYinghai Lu depends on MTRR_SANITIZER 14788f9ca475SIngo Molnar ---help--- 147912031a62SYinghai Lu mtrr cleanup spare entries default, it can be changed via 1480aba3728cSThomas Gleixner mtrr_spare_reg_nr=N on the kernel command line. 148112031a62SYinghai Lu 14822e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT 14836fc108a0SJan Beulich def_bool y 14846a108a14SDavid Rientjes prompt "x86 PAT support" if EXPERT 14852a8a2719SIngo Molnar depends on MTRR 14868f9ca475SIngo Molnar ---help--- 14872e5d9c85Svenkatesh.pallipadi@intel.com Use PAT attributes to setup page level cache control. 1488042b78e4SVenki Pallipadi 14892e5d9c85Svenkatesh.pallipadi@intel.com PATs are the modern equivalents of MTRRs and are much more 14902e5d9c85Svenkatesh.pallipadi@intel.com flexible than MTRRs. 14912e5d9c85Svenkatesh.pallipadi@intel.com 14922e5d9c85Svenkatesh.pallipadi@intel.com Say N here if you see bootup problems (boot crash, boot hang, 1493042b78e4SVenki Pallipadi spontaneous reboots) or a non-working video driver. 14942e5d9c85Svenkatesh.pallipadi@intel.com 14952e5d9c85Svenkatesh.pallipadi@intel.com If unsure, say Y. 14962e5d9c85Svenkatesh.pallipadi@intel.com 149746cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED 149846cf98cdSVenkatesh Pallipadi def_bool y 149946cf98cdSVenkatesh Pallipadi depends on X86_PAT 150046cf98cdSVenkatesh Pallipadi 1501628c6246SH. Peter Anvinconfig ARCH_RANDOM 1502628c6246SH. Peter Anvin def_bool y 1503628c6246SH. Peter Anvin prompt "x86 architectural random number generator" if EXPERT 1504628c6246SH. Peter Anvin ---help--- 1505628c6246SH. Peter Anvin Enable the x86 architectural RDRAND instruction 1506628c6246SH. Peter Anvin (Intel Bull Mountain technology) to generate random numbers. 1507628c6246SH. Peter Anvin If supported, this is a high bandwidth, cryptographically 1508628c6246SH. Peter Anvin secure hardware random number generator. 1509628c6246SH. Peter Anvin 151051ae4a2dSH. Peter Anvinconfig X86_SMAP 151151ae4a2dSH. Peter Anvin def_bool y 151251ae4a2dSH. Peter Anvin prompt "Supervisor Mode Access Prevention" if EXPERT 151351ae4a2dSH. Peter Anvin ---help--- 151451ae4a2dSH. Peter Anvin Supervisor Mode Access Prevention (SMAP) is a security 151551ae4a2dSH. Peter Anvin feature in newer Intel processors. There is a small 151651ae4a2dSH. Peter Anvin performance cost if this enabled and turned on; there is 151751ae4a2dSH. Peter Anvin also a small increase in the kernel size if this is enabled. 151851ae4a2dSH. Peter Anvin 151951ae4a2dSH. Peter Anvin If unsure, say Y. 152051ae4a2dSH. Peter Anvin 1521506f1d07SSam Ravnborgconfig EFI 15229ba16087SJan Beulich bool "EFI runtime service support" 15235b83683fSHuang, Ying depends on ACPI 1524f6ce5002SSergey Vlasov select UCS2_STRING 1525506f1d07SSam Ravnborg ---help--- 15268b2cb7a8SHuang, Ying This enables the kernel to use EFI runtime services that are 1527506f1d07SSam Ravnborg available (such as the EFI variable services). 1528506f1d07SSam Ravnborg 15298b2cb7a8SHuang, Ying This option is only useful on systems that have EFI firmware. 15308b2cb7a8SHuang, Ying In addition, you should use the latest ELILO loader available 15318b2cb7a8SHuang, Ying at <http://elilo.sourceforge.net> in order to take advantage 15328b2cb7a8SHuang, Ying of EFI runtime services. However, even with this option, the 15338b2cb7a8SHuang, Ying resultant kernel should continue to boot on existing non-EFI 15348b2cb7a8SHuang, Ying platforms. 1535506f1d07SSam Ravnborg 1536291f3632SMatt Flemingconfig EFI_STUB 1537291f3632SMatt Fleming bool "EFI stub support" 1538291f3632SMatt Fleming depends on EFI 1539291f3632SMatt Fleming ---help--- 1540291f3632SMatt Fleming This kernel feature allows a bzImage to be loaded directly 1541291f3632SMatt Fleming by EFI firmware without the use of a bootloader. 1542291f3632SMatt Fleming 15434172fe2fSRoy Franz See Documentation/efi-stub.txt for more information. 15440c759662SMatt Fleming 15457d453eeeSMatt Flemingconfig EFI_MIXED 15467d453eeeSMatt Fleming bool "EFI mixed-mode support" 15477d453eeeSMatt Fleming depends on EFI_STUB && X86_64 15487d453eeeSMatt Fleming ---help--- 15497d453eeeSMatt Fleming Enabling this feature allows a 64-bit kernel to be booted 15507d453eeeSMatt Fleming on a 32-bit firmware, provided that your CPU supports 64-bit 15517d453eeeSMatt Fleming mode. 15527d453eeeSMatt Fleming 15537d453eeeSMatt Fleming Note that it is not possible to boot a mixed-mode enabled 15547d453eeeSMatt Fleming kernel via the EFI boot stub - a bootloader that supports 15557d453eeeSMatt Fleming the EFI handover protocol must be used. 15567d453eeeSMatt Fleming 15577d453eeeSMatt Fleming If unsure, say N. 15587d453eeeSMatt Fleming 1559506f1d07SSam Ravnborgconfig SECCOMP 15603c2362e6SHarvey Harrison def_bool y 15613c2362e6SHarvey Harrison prompt "Enable seccomp to safely compute untrusted bytecode" 15628f9ca475SIngo Molnar ---help--- 1563506f1d07SSam Ravnborg This kernel feature is useful for number crunching applications 1564506f1d07SSam Ravnborg that may need to compute untrusted bytecode during their 1565506f1d07SSam Ravnborg execution. By using pipes or other transports made available to 1566506f1d07SSam Ravnborg the process as file descriptors supporting the read/write 1567506f1d07SSam Ravnborg syscalls, it's possible to isolate those applications in 1568506f1d07SSam Ravnborg their own address space using seccomp. Once seccomp is 15699c0bbee8SAlexey Dobriyan enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1570506f1d07SSam Ravnborg and the task is only allowed to execute a few safe syscalls 1571506f1d07SSam Ravnborg defined by each seccomp mode. 1572506f1d07SSam Ravnborg 1573506f1d07SSam Ravnborg If unsure, say Y. Only embedded should say N here. 1574506f1d07SSam Ravnborg 1575506f1d07SSam Ravnborgsource kernel/Kconfig.hz 1576506f1d07SSam Ravnborg 1577506f1d07SSam Ravnborgconfig KEXEC 1578506f1d07SSam Ravnborg bool "kexec system call" 15798f9ca475SIngo Molnar ---help--- 1580506f1d07SSam Ravnborg kexec is a system call that implements the ability to shutdown your 1581506f1d07SSam Ravnborg current kernel, and to start another kernel. It is like a reboot 1582506f1d07SSam Ravnborg but it is independent of the system firmware. And like a reboot 1583506f1d07SSam Ravnborg you can start any kernel with it, not just Linux. 1584506f1d07SSam Ravnborg 1585506f1d07SSam Ravnborg The name comes from the similarity to the exec system call. 1586506f1d07SSam Ravnborg 1587506f1d07SSam Ravnborg It is an ongoing process to be certain the hardware in a machine 1588506f1d07SSam Ravnborg is properly shutdown, so do not be surprised if this code does not 1589bf220695SGeert Uytterhoeven initially work for you. As of this writing the exact hardware 1590bf220695SGeert Uytterhoeven interface is strongly in flux, so no good recommendation can be 1591bf220695SGeert Uytterhoeven made. 1592506f1d07SSam Ravnborg 1593506f1d07SSam Ravnborgconfig CRASH_DUMP 159404b69447SPavel Machek bool "kernel crash dumps" 1595506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 15968f9ca475SIngo Molnar ---help--- 1597506f1d07SSam Ravnborg Generate crash dump after being started by kexec. 1598506f1d07SSam Ravnborg This should be normally only set in special crash dump kernels 1599506f1d07SSam Ravnborg which are loaded in the main kernel with kexec-tools into 1600506f1d07SSam Ravnborg a specially reserved region and then later executed after 1601506f1d07SSam Ravnborg a crash by kdump/kexec. The crash dump kernel must be compiled 1602506f1d07SSam Ravnborg to a memory address not used by the main kernel or BIOS using 1603506f1d07SSam Ravnborg PHYSICAL_START, or it must be built as a relocatable image 1604506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y). 1605506f1d07SSam Ravnborg For more details see Documentation/kdump/kdump.txt 1606506f1d07SSam Ravnborg 16073ab83521SHuang Yingconfig KEXEC_JUMP 16086ea30386SKees Cook bool "kexec jump" 1609fee7b0d8SHuang Ying depends on KEXEC && HIBERNATION 16108f9ca475SIngo Molnar ---help--- 161189081d17SHuang Ying Jump between original kernel and kexeced kernel and invoke 161289081d17SHuang Ying code in physical address mode via KEXEC 16133ab83521SHuang Ying 1614506f1d07SSam Ravnborgconfig PHYSICAL_START 16156a108a14SDavid Rientjes hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1616ceefccc9SH. Peter Anvin default "0x1000000" 16178f9ca475SIngo Molnar ---help--- 1618506f1d07SSam Ravnborg This gives the physical address where the kernel is loaded. 1619506f1d07SSam Ravnborg 1620506f1d07SSam Ravnborg If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1621506f1d07SSam Ravnborg bzImage will decompress itself to above physical address and 1622506f1d07SSam Ravnborg run from there. Otherwise, bzImage will run from the address where 1623506f1d07SSam Ravnborg it has been loaded by the boot loader and will ignore above physical 1624506f1d07SSam Ravnborg address. 1625506f1d07SSam Ravnborg 1626506f1d07SSam Ravnborg In normal kdump cases one does not have to set/change this option 1627506f1d07SSam Ravnborg as now bzImage can be compiled as a completely relocatable image 1628506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1629506f1d07SSam Ravnborg address. This option is mainly useful for the folks who don't want 1630506f1d07SSam Ravnborg to use a bzImage for capturing the crash dump and want to use a 1631506f1d07SSam Ravnborg vmlinux instead. vmlinux is not relocatable hence a kernel needs 1632506f1d07SSam Ravnborg to be specifically compiled to run from a specific memory area 1633506f1d07SSam Ravnborg (normally a reserved region) and this option comes handy. 1634506f1d07SSam Ravnborg 1635ceefccc9SH. Peter Anvin So if you are using bzImage for capturing the crash dump, 1636ceefccc9SH. Peter Anvin leave the value here unchanged to 0x1000000 and set 1637ceefccc9SH. Peter Anvin CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1638ceefccc9SH. Peter Anvin for capturing the crash dump change this value to start of 1639ceefccc9SH. Peter Anvin the reserved region. In other words, it can be set based on 1640ceefccc9SH. Peter Anvin the "X" value as specified in the "crashkernel=YM@XM" 1641ceefccc9SH. Peter Anvin command line boot parameter passed to the panic-ed 1642ceefccc9SH. Peter Anvin kernel. Please take a look at Documentation/kdump/kdump.txt 1643ceefccc9SH. Peter Anvin for more details about crash dumps. 1644506f1d07SSam Ravnborg 1645506f1d07SSam Ravnborg Usage of bzImage for capturing the crash dump is recommended as 1646506f1d07SSam Ravnborg one does not have to build two kernels. Same kernel can be used 1647506f1d07SSam Ravnborg as production kernel and capture kernel. Above option should have 1648506f1d07SSam Ravnborg gone away after relocatable bzImage support is introduced. But it 1649506f1d07SSam Ravnborg is present because there are users out there who continue to use 1650506f1d07SSam Ravnborg vmlinux for dump capture. This option should go away down the 1651506f1d07SSam Ravnborg line. 1652506f1d07SSam Ravnborg 1653506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 1654506f1d07SSam Ravnborg 1655506f1d07SSam Ravnborgconfig RELOCATABLE 165626717808SH. Peter Anvin bool "Build a relocatable kernel" 165726717808SH. Peter Anvin default y 16588f9ca475SIngo Molnar ---help--- 1659506f1d07SSam Ravnborg This builds a kernel image that retains relocation information 1660506f1d07SSam Ravnborg so it can be loaded someplace besides the default 1MB. 1661506f1d07SSam Ravnborg The relocations tend to make the kernel binary about 10% larger, 1662506f1d07SSam Ravnborg but are discarded at runtime. 1663506f1d07SSam Ravnborg 1664506f1d07SSam Ravnborg One use is for the kexec on panic case where the recovery kernel 1665506f1d07SSam Ravnborg must live at a different physical address than the primary 1666506f1d07SSam Ravnborg kernel. 1667506f1d07SSam Ravnborg 1668506f1d07SSam Ravnborg Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1669506f1d07SSam Ravnborg it has been loaded at and the compile time physical address 16708ab3820fSKees Cook (CONFIG_PHYSICAL_START) is used as the minimum location. 1671506f1d07SSam Ravnborg 16728ab3820fSKees Cookconfig RANDOMIZE_BASE 16738ab3820fSKees Cook bool "Randomize the address of the kernel image" 16748ab3820fSKees Cook depends on RELOCATABLE 16758ab3820fSKees Cook default n 16768ab3820fSKees Cook ---help--- 16778ab3820fSKees Cook Randomizes the physical and virtual address at which the 16788ab3820fSKees Cook kernel image is decompressed, as a security feature that 16798ab3820fSKees Cook deters exploit attempts relying on knowledge of the location 16808ab3820fSKees Cook of kernel internals. 16818ab3820fSKees Cook 1682a653f356SKees Cook Entropy is generated using the RDRAND instruction if it is 1683a653f356SKees Cook supported. If RDTSC is supported, it is used as well. If 1684a653f356SKees Cook neither RDRAND nor RDTSC are supported, then randomness is 1685a653f356SKees Cook read from the i8254 timer. 16868ab3820fSKees Cook 16878ab3820fSKees Cook The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET, 1688a653f356SKees Cook and aligned according to PHYSICAL_ALIGN. Since the kernel is 1689a653f356SKees Cook built using 2GiB addressing, and PHYSICAL_ALGIN must be at a 1690a653f356SKees Cook minimum of 2MiB, only 10 bits of entropy is theoretically 1691a653f356SKees Cook possible. At best, due to page table layouts, 64-bit can use 1692a653f356SKees Cook 9 bits of entropy and 32-bit uses 8 bits. 16938ab3820fSKees Cook 1694da2b6fb9SKees Cook If unsure, say N. 1695da2b6fb9SKees Cook 16968ab3820fSKees Cookconfig RANDOMIZE_BASE_MAX_OFFSET 1697da2b6fb9SKees Cook hex "Maximum kASLR offset allowed" if EXPERT 16988ab3820fSKees Cook depends on RANDOMIZE_BASE 16996145cfe3SKees Cook range 0x0 0x20000000 if X86_32 17006145cfe3SKees Cook default "0x20000000" if X86_32 17016145cfe3SKees Cook range 0x0 0x40000000 if X86_64 17026145cfe3SKees Cook default "0x40000000" if X86_64 17038ab3820fSKees Cook ---help--- 1704da2b6fb9SKees Cook The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical 1705da2b6fb9SKees Cook memory is used to determine the maximal offset in bytes that will 1706da2b6fb9SKees Cook be applied to the kernel when kernel Address Space Layout 1707da2b6fb9SKees Cook Randomization (kASLR) is active. This must be a multiple of 1708da2b6fb9SKees Cook PHYSICAL_ALIGN. 17096145cfe3SKees Cook 1710da2b6fb9SKees Cook On 32-bit this is limited to 512MiB by page table layouts. The 1711da2b6fb9SKees Cook default is 512MiB. 17126145cfe3SKees Cook 17136145cfe3SKees Cook On 64-bit this is limited by how the kernel fixmap page table is 1714da2b6fb9SKees Cook positioned, so this cannot be larger than 1GiB currently. Without 1715da2b6fb9SKees Cook RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel 1716da2b6fb9SKees Cook and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the 1717da2b6fb9SKees Cook modules area will shrink to compensate, up to the current maximum 1718da2b6fb9SKees Cook 1GiB to 1GiB split. The default is 1GiB. 1719da2b6fb9SKees Cook 1720da2b6fb9SKees Cook If unsure, leave at the default value. 17218ab3820fSKees Cook 17228ab3820fSKees Cook# Relocation on x86 needs some additional build support 1723845adf72SH. Peter Anvinconfig X86_NEED_RELOCS 1724845adf72SH. Peter Anvin def_bool y 17258ab3820fSKees Cook depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 1726845adf72SH. Peter Anvin 1727506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN 1728a0215061SKees Cook hex "Alignment value to which kernel should be aligned" 17298ab3820fSKees Cook default "0x200000" 1730a0215061SKees Cook range 0x2000 0x1000000 if X86_32 1731a0215061SKees Cook range 0x200000 0x1000000 if X86_64 17328f9ca475SIngo Molnar ---help--- 1733506f1d07SSam Ravnborg This value puts the alignment restrictions on physical address 1734506f1d07SSam Ravnborg where kernel is loaded and run from. Kernel is compiled for an 1735506f1d07SSam Ravnborg address which meets above alignment restriction. 1736506f1d07SSam Ravnborg 1737506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 1738506f1d07SSam Ravnborg CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1739506f1d07SSam Ravnborg address aligned to above value and run from there. 1740506f1d07SSam Ravnborg 1741506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 1742506f1d07SSam Ravnborg CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1743506f1d07SSam Ravnborg load address and decompress itself to the address it has been 1744506f1d07SSam Ravnborg compiled for and run from there. The address for which kernel is 1745506f1d07SSam Ravnborg compiled already meets above alignment restrictions. Hence the 1746506f1d07SSam Ravnborg end result is that kernel runs from a physical address meeting 1747506f1d07SSam Ravnborg above alignment restrictions. 1748506f1d07SSam Ravnborg 1749a0215061SKees Cook On 32-bit this value must be a multiple of 0x2000. On 64-bit 1750a0215061SKees Cook this value must be a multiple of 0x200000. 1751a0215061SKees Cook 1752506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 1753506f1d07SSam Ravnborg 1754506f1d07SSam Ravnborgconfig HOTPLUG_CPU 17557c13e6a3SDimitri Sivanich bool "Support for hot-pluggable CPUs" 175640b31360SStephen Rothwell depends on SMP 1757506f1d07SSam Ravnborg ---help--- 17587c13e6a3SDimitri Sivanich Say Y here to allow turning CPUs off and on. CPUs can be 17597c13e6a3SDimitri Sivanich controlled through /sys/devices/system/cpu. 17607c13e6a3SDimitri Sivanich ( Note: power management support will enable this option 17617c13e6a3SDimitri Sivanich automatically on SMP systems. ) 17627c13e6a3SDimitri Sivanich Say N if you want to disable CPU hotplug. 1763506f1d07SSam Ravnborg 176480aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0 176580aa1dffSFenghua Yu bool "Set default setting of cpu0_hotpluggable" 176680aa1dffSFenghua Yu default n 17672c922cd0SKees Cook depends on HOTPLUG_CPU 176880aa1dffSFenghua Yu ---help--- 176980aa1dffSFenghua Yu Set whether default state of cpu0_hotpluggable is on or off. 177080aa1dffSFenghua Yu 177180aa1dffSFenghua Yu Say Y here to enable CPU0 hotplug by default. If this switch 177280aa1dffSFenghua Yu is turned on, there is no need to give cpu0_hotplug kernel 177380aa1dffSFenghua Yu parameter and the CPU0 hotplug feature is enabled by default. 177480aa1dffSFenghua Yu 177580aa1dffSFenghua Yu Please note: there are two known CPU0 dependencies if you want 177680aa1dffSFenghua Yu to enable the CPU0 hotplug feature either by this switch or by 177780aa1dffSFenghua Yu cpu0_hotplug kernel parameter. 177880aa1dffSFenghua Yu 177980aa1dffSFenghua Yu First, resume from hibernate or suspend always starts from CPU0. 178080aa1dffSFenghua Yu So hibernate and suspend are prevented if CPU0 is offline. 178180aa1dffSFenghua Yu 178280aa1dffSFenghua Yu Second dependency is PIC interrupts always go to CPU0. CPU0 can not 178380aa1dffSFenghua Yu offline if any interrupt can not migrate out of CPU0. There may 178480aa1dffSFenghua Yu be other CPU0 dependencies. 178580aa1dffSFenghua Yu 178680aa1dffSFenghua Yu Please make sure the dependencies are under your control before 178780aa1dffSFenghua Yu you enable this feature. 178880aa1dffSFenghua Yu 178980aa1dffSFenghua Yu Say N if you don't want to enable CPU0 hotplug feature by default. 179080aa1dffSFenghua Yu You still can enable the CPU0 hotplug feature at boot by kernel 179180aa1dffSFenghua Yu parameter cpu0_hotplug. 179280aa1dffSFenghua Yu 1793a71c8bc5SFenghua Yuconfig DEBUG_HOTPLUG_CPU0 1794a71c8bc5SFenghua Yu def_bool n 1795a71c8bc5SFenghua Yu prompt "Debug CPU0 hotplug" 17962c922cd0SKees Cook depends on HOTPLUG_CPU 1797a71c8bc5SFenghua Yu ---help--- 1798a71c8bc5SFenghua Yu Enabling this option offlines CPU0 (if CPU0 can be offlined) as 1799a71c8bc5SFenghua Yu soon as possible and boots up userspace with CPU0 offlined. User 1800a71c8bc5SFenghua Yu can online CPU0 back after boot time. 1801a71c8bc5SFenghua Yu 1802a71c8bc5SFenghua Yu To debug CPU0 hotplug, you need to enable CPU0 offline/online 1803a71c8bc5SFenghua Yu feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 1804a71c8bc5SFenghua Yu compilation or giving cpu0_hotplug kernel parameter at boot. 1805a71c8bc5SFenghua Yu 1806a71c8bc5SFenghua Yu If unsure, say N. 1807a71c8bc5SFenghua Yu 1808506f1d07SSam Ravnborgconfig COMPAT_VDSO 1809b0b49f26SAndy Lutomirski def_bool n 1810b0b49f26SAndy Lutomirski prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 1811af65d648SRoland McGrath depends on X86_32 || IA32_EMULATION 18128f9ca475SIngo Molnar ---help--- 1813b0b49f26SAndy Lutomirski Certain buggy versions of glibc will crash if they are 1814b0b49f26SAndy Lutomirski presented with a 32-bit vDSO that is not mapped at the address 1815b0b49f26SAndy Lutomirski indicated in its segment table. 1816e84446deSRandy Dunlap 1817b0b49f26SAndy Lutomirski The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 1818b0b49f26SAndy Lutomirski and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 1819b0b49f26SAndy Lutomirski 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 1820b0b49f26SAndy Lutomirski the only released version with the bug, but OpenSUSE 9 1821b0b49f26SAndy Lutomirski contains a buggy "glibc 2.3.2". 1822506f1d07SSam Ravnborg 1823b0b49f26SAndy Lutomirski The symptom of the bug is that everything crashes on startup, saying: 1824b0b49f26SAndy Lutomirski dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 1825b0b49f26SAndy Lutomirski 1826b0b49f26SAndy Lutomirski Saying Y here changes the default value of the vdso32 boot 1827b0b49f26SAndy Lutomirski option from 1 to 0, which turns off the 32-bit vDSO entirely. 1828b0b49f26SAndy Lutomirski This works around the glibc bug but hurts performance. 1829b0b49f26SAndy Lutomirski 1830b0b49f26SAndy Lutomirski If unsure, say N: if you are compiling your own kernel, you 1831b0b49f26SAndy Lutomirski are unlikely to be using a buggy version of glibc. 1832506f1d07SSam Ravnborg 1833516cbf37STim Birdconfig CMDLINE_BOOL 1834516cbf37STim Bird bool "Built-in kernel command line" 18358f9ca475SIngo Molnar ---help--- 1836516cbf37STim Bird Allow for specifying boot arguments to the kernel at 1837516cbf37STim Bird build time. On some systems (e.g. embedded ones), it is 1838516cbf37STim Bird necessary or convenient to provide some or all of the 1839516cbf37STim Bird kernel boot arguments with the kernel itself (that is, 1840516cbf37STim Bird to not rely on the boot loader to provide them.) 1841516cbf37STim Bird 1842516cbf37STim Bird To compile command line arguments into the kernel, 1843516cbf37STim Bird set this option to 'Y', then fill in the 1844516cbf37STim Bird the boot arguments in CONFIG_CMDLINE. 1845516cbf37STim Bird 1846516cbf37STim Bird Systems with fully functional boot loaders (i.e. non-embedded) 1847516cbf37STim Bird should leave this option set to 'N'. 1848516cbf37STim Bird 1849516cbf37STim Birdconfig CMDLINE 1850516cbf37STim Bird string "Built-in kernel command string" 1851516cbf37STim Bird depends on CMDLINE_BOOL 1852516cbf37STim Bird default "" 18538f9ca475SIngo Molnar ---help--- 1854516cbf37STim Bird Enter arguments here that should be compiled into the kernel 1855516cbf37STim Bird image and used at boot time. If the boot loader provides a 1856516cbf37STim Bird command line at boot time, it is appended to this string to 1857516cbf37STim Bird form the full kernel command line, when the system boots. 1858516cbf37STim Bird 1859516cbf37STim Bird However, you can use the CONFIG_CMDLINE_OVERRIDE option to 1860516cbf37STim Bird change this behavior. 1861516cbf37STim Bird 1862516cbf37STim Bird In most cases, the command line (whether built-in or provided 1863516cbf37STim Bird by the boot loader) should specify the device for the root 1864516cbf37STim Bird file system. 1865516cbf37STim Bird 1866516cbf37STim Birdconfig CMDLINE_OVERRIDE 1867516cbf37STim Bird bool "Built-in command line overrides boot loader arguments" 1868516cbf37STim Bird depends on CMDLINE_BOOL 18698f9ca475SIngo Molnar ---help--- 1870516cbf37STim Bird Set this option to 'Y' to have the kernel ignore the boot loader 1871516cbf37STim Bird command line, and use ONLY the built-in command line. 1872516cbf37STim Bird 1873516cbf37STim Bird This is used to work around broken boot loaders. This should 1874516cbf37STim Bird be set to 'N' under normal conditions. 1875516cbf37STim Bird 1876506f1d07SSam Ravnborgendmenu 1877506f1d07SSam Ravnborg 1878506f1d07SSam Ravnborgconfig ARCH_ENABLE_MEMORY_HOTPLUG 1879506f1d07SSam Ravnborg def_bool y 1880506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 1881506f1d07SSam Ravnborg 188235551053SGary Hadeconfig ARCH_ENABLE_MEMORY_HOTREMOVE 188335551053SGary Hade def_bool y 188435551053SGary Hade depends on MEMORY_HOTPLUG 188535551053SGary Hade 1886e534c7c5SLee Schermerhornconfig USE_PERCPU_NUMA_NODE_ID 1887645a7919STejun Heo def_bool y 1888e534c7c5SLee Schermerhorn depends on NUMA 1889e534c7c5SLee Schermerhorn 18909491846fSKirill A. Shutemovconfig ARCH_ENABLE_SPLIT_PMD_PTLOCK 18919491846fSKirill A. Shutemov def_bool y 18929491846fSKirill A. Shutemov depends on X86_64 || X86_PAE 18939491846fSKirill A. Shutemov 1894c177c81eSNaoya Horiguchiconfig ARCH_ENABLE_HUGEPAGE_MIGRATION 1895c177c81eSNaoya Horiguchi def_bool y 1896c177c81eSNaoya Horiguchi depends on X86_64 && HUGETLB_PAGE && MIGRATION 1897c177c81eSNaoya Horiguchi 1898da85f865SBjorn Helgaasmenu "Power management and ACPI options" 1899e279b6c1SSam Ravnborg 1900e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER 19013c2362e6SHarvey Harrison def_bool y 1902e279b6c1SSam Ravnborg depends on X86_64 && HIBERNATION 1903e279b6c1SSam Ravnborg 1904e279b6c1SSam Ravnborgsource "kernel/power/Kconfig" 1905e279b6c1SSam Ravnborg 1906e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig" 1907e279b6c1SSam Ravnborg 1908efafc8b2SFeng Tangsource "drivers/sfi/Kconfig" 1909efafc8b2SFeng Tang 1910a6b68076SAndi Kleenconfig X86_APM_BOOT 19116fc108a0SJan Beulich def_bool y 1912282e5aabSPaul Bolle depends on APM 1913a6b68076SAndi Kleen 1914e279b6c1SSam Ravnborgmenuconfig APM 1915e279b6c1SSam Ravnborg tristate "APM (Advanced Power Management) BIOS support" 1916efefa6f6SIngo Molnar depends on X86_32 && PM_SLEEP 1917e279b6c1SSam Ravnborg ---help--- 1918e279b6c1SSam Ravnborg APM is a BIOS specification for saving power using several different 1919e279b6c1SSam Ravnborg techniques. This is mostly useful for battery powered laptops with 1920e279b6c1SSam Ravnborg APM compliant BIOSes. If you say Y here, the system time will be 1921e279b6c1SSam Ravnborg reset after a RESUME operation, the /proc/apm device will provide 1922e279b6c1SSam Ravnborg battery status information, and user-space programs will receive 1923e279b6c1SSam Ravnborg notification of APM "events" (e.g. battery status change). 1924e279b6c1SSam Ravnborg 1925e279b6c1SSam Ravnborg If you select "Y" here, you can disable actual use of the APM 1926e279b6c1SSam Ravnborg BIOS by passing the "apm=off" option to the kernel at boot time. 1927e279b6c1SSam Ravnborg 1928e279b6c1SSam Ravnborg Note that the APM support is almost completely disabled for 1929e279b6c1SSam Ravnborg machines with more than one CPU. 1930e279b6c1SSam Ravnborg 1931e279b6c1SSam Ravnborg In order to use APM, you will need supporting software. For location 19322dc98fd3SMichael Witten and more information, read <file:Documentation/power/apm-acpi.txt> 19332dc98fd3SMichael Witten and the Battery Powered Linux mini-HOWTO, available from 1934e279b6c1SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 1935e279b6c1SSam Ravnborg 1936e279b6c1SSam Ravnborg This driver does not spin down disk drives (see the hdparm(8) 1937e279b6c1SSam Ravnborg manpage ("man 8 hdparm") for that), and it doesn't turn off 1938e279b6c1SSam Ravnborg VESA-compliant "green" monitors. 1939e279b6c1SSam Ravnborg 1940e279b6c1SSam Ravnborg This driver does not support the TI 4000M TravelMate and the ACER 1941e279b6c1SSam Ravnborg 486/DX4/75 because they don't have compliant BIOSes. Many "green" 1942e279b6c1SSam Ravnborg desktop machines also don't have compliant BIOSes, and this driver 1943e279b6c1SSam Ravnborg may cause those machines to panic during the boot phase. 1944e279b6c1SSam Ravnborg 1945e279b6c1SSam Ravnborg Generally, if you don't have a battery in your machine, there isn't 1946e279b6c1SSam Ravnborg much point in using this driver and you should say N. If you get 1947e279b6c1SSam Ravnborg random kernel OOPSes or reboots that don't seem to be related to 1948e279b6c1SSam Ravnborg anything, try disabling/enabling this option (or disabling/enabling 1949e279b6c1SSam Ravnborg APM in your BIOS). 1950e279b6c1SSam Ravnborg 1951e279b6c1SSam Ravnborg Some other things you should try when experiencing seemingly random, 1952e279b6c1SSam Ravnborg "weird" problems: 1953e279b6c1SSam Ravnborg 1954e279b6c1SSam Ravnborg 1) make sure that you have enough swap space and that it is 1955e279b6c1SSam Ravnborg enabled. 1956e279b6c1SSam Ravnborg 2) pass the "no-hlt" option to the kernel 1957e279b6c1SSam Ravnborg 3) switch on floating point emulation in the kernel and pass 1958e279b6c1SSam Ravnborg the "no387" option to the kernel 1959e279b6c1SSam Ravnborg 4) pass the "floppy=nodma" option to the kernel 1960e279b6c1SSam Ravnborg 5) pass the "mem=4M" option to the kernel (thereby disabling 1961e279b6c1SSam Ravnborg all but the first 4 MB of RAM) 1962e279b6c1SSam Ravnborg 6) make sure that the CPU is not over clocked. 1963e279b6c1SSam Ravnborg 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 1964e279b6c1SSam Ravnborg 8) disable the cache from your BIOS settings 1965e279b6c1SSam Ravnborg 9) install a fan for the video card or exchange video RAM 1966e279b6c1SSam Ravnborg 10) install a better fan for the CPU 1967e279b6c1SSam Ravnborg 11) exchange RAM chips 1968e279b6c1SSam Ravnborg 12) exchange the motherboard. 1969e279b6c1SSam Ravnborg 1970e279b6c1SSam Ravnborg To compile this driver as a module, choose M here: the 1971e279b6c1SSam Ravnborg module will be called apm. 1972e279b6c1SSam Ravnborg 1973e279b6c1SSam Ravnborgif APM 1974e279b6c1SSam Ravnborg 1975e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND 1976e279b6c1SSam Ravnborg bool "Ignore USER SUSPEND" 19778f9ca475SIngo Molnar ---help--- 1978e279b6c1SSam Ravnborg This option will ignore USER SUSPEND requests. On machines with a 1979e279b6c1SSam Ravnborg compliant APM BIOS, you want to say N. However, on the NEC Versa M 1980e279b6c1SSam Ravnborg series notebooks, it is necessary to say Y because of a BIOS bug. 1981e279b6c1SSam Ravnborg 1982e279b6c1SSam Ravnborgconfig APM_DO_ENABLE 1983e279b6c1SSam Ravnborg bool "Enable PM at boot time" 1984e279b6c1SSam Ravnborg ---help--- 1985e279b6c1SSam Ravnborg Enable APM features at boot time. From page 36 of the APM BIOS 1986e279b6c1SSam Ravnborg specification: "When disabled, the APM BIOS does not automatically 1987e279b6c1SSam Ravnborg power manage devices, enter the Standby State, enter the Suspend 1988e279b6c1SSam Ravnborg State, or take power saving steps in response to CPU Idle calls." 1989e279b6c1SSam Ravnborg This driver will make CPU Idle calls when Linux is idle (unless this 1990e279b6c1SSam Ravnborg feature is turned off -- see "Do CPU IDLE calls", below). This 1991e279b6c1SSam Ravnborg should always save battery power, but more complicated APM features 1992e279b6c1SSam Ravnborg will be dependent on your BIOS implementation. You may need to turn 1993e279b6c1SSam Ravnborg this option off if your computer hangs at boot time when using APM 1994e279b6c1SSam Ravnborg support, or if it beeps continuously instead of suspending. Turn 1995e279b6c1SSam Ravnborg this off if you have a NEC UltraLite Versa 33/C or a Toshiba 1996e279b6c1SSam Ravnborg T400CDT. This is off by default since most machines do fine without 1997e279b6c1SSam Ravnborg this feature. 1998e279b6c1SSam Ravnborg 1999e279b6c1SSam Ravnborgconfig APM_CPU_IDLE 2000dd8af076SLen Brown depends on CPU_IDLE 2001e279b6c1SSam Ravnborg bool "Make CPU Idle calls when idle" 20028f9ca475SIngo Molnar ---help--- 2003e279b6c1SSam Ravnborg Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2004e279b6c1SSam Ravnborg On some machines, this can activate improved power savings, such as 2005e279b6c1SSam Ravnborg a slowed CPU clock rate, when the machine is idle. These idle calls 2006e279b6c1SSam Ravnborg are made after the idle loop has run for some length of time (e.g., 2007e279b6c1SSam Ravnborg 333 mS). On some machines, this will cause a hang at boot time or 2008e279b6c1SSam Ravnborg whenever the CPU becomes idle. (On machines with more than one CPU, 2009e279b6c1SSam Ravnborg this option does nothing.) 2010e279b6c1SSam Ravnborg 2011e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK 2012e279b6c1SSam Ravnborg bool "Enable console blanking using APM" 20138f9ca475SIngo Molnar ---help--- 2014e279b6c1SSam Ravnborg Enable console blanking using the APM. Some laptops can use this to 2015e279b6c1SSam Ravnborg turn off the LCD backlight when the screen blanker of the Linux 2016e279b6c1SSam Ravnborg virtual console blanks the screen. Note that this is only used by 2017e279b6c1SSam Ravnborg the virtual console screen blanker, and won't turn off the backlight 2018e279b6c1SSam Ravnborg when using the X Window system. This also doesn't have anything to 2019e279b6c1SSam Ravnborg do with your VESA-compliant power-saving monitor. Further, this 2020e279b6c1SSam Ravnborg option doesn't work for all laptops -- it might not turn off your 2021e279b6c1SSam Ravnborg backlight at all, or it might print a lot of errors to the console, 2022e279b6c1SSam Ravnborg especially if you are using gpm. 2023e279b6c1SSam Ravnborg 2024e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS 2025e279b6c1SSam Ravnborg bool "Allow interrupts during APM BIOS calls" 20268f9ca475SIngo Molnar ---help--- 2027e279b6c1SSam Ravnborg Normally we disable external interrupts while we are making calls to 2028e279b6c1SSam Ravnborg the APM BIOS as a measure to lessen the effects of a badly behaving 2029e279b6c1SSam Ravnborg BIOS implementation. The BIOS should reenable interrupts if it 2030e279b6c1SSam Ravnborg needs to. Unfortunately, some BIOSes do not -- especially those in 2031e279b6c1SSam Ravnborg many of the newer IBM Thinkpads. If you experience hangs when you 2032e279b6c1SSam Ravnborg suspend, try setting this to Y. Otherwise, say N. 2033e279b6c1SSam Ravnborg 2034e279b6c1SSam Ravnborgendif # APM 2035e279b6c1SSam Ravnborg 2036bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig" 2037e279b6c1SSam Ravnborg 2038e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig" 2039e279b6c1SSam Ravnborg 204027471fdbSAndy Henroidsource "drivers/idle/Kconfig" 204127471fdbSAndy Henroid 2042e279b6c1SSam Ravnborgendmenu 2043e279b6c1SSam Ravnborg 2044e279b6c1SSam Ravnborg 2045e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)" 2046e279b6c1SSam Ravnborg 2047e279b6c1SSam Ravnborgconfig PCI 20481ac97018SIngo Molnar bool "PCI support" 20491c858087SAdrian Bunk default y 20508f9ca475SIngo Molnar ---help--- 2051e279b6c1SSam Ravnborg Find out whether you have a PCI motherboard. PCI is the name of a 2052e279b6c1SSam Ravnborg bus system, i.e. the way the CPU talks to the other stuff inside 2053e279b6c1SSam Ravnborg your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2054e279b6c1SSam Ravnborg VESA. If you have PCI, say Y, otherwise N. 2055e279b6c1SSam Ravnborg 2056e279b6c1SSam Ravnborgchoice 2057e279b6c1SSam Ravnborg prompt "PCI access mode" 2058efefa6f6SIngo Molnar depends on X86_32 && PCI 2059e279b6c1SSam Ravnborg default PCI_GOANY 2060e279b6c1SSam Ravnborg ---help--- 2061e279b6c1SSam Ravnborg On PCI systems, the BIOS can be used to detect the PCI devices and 2062e279b6c1SSam Ravnborg determine their configuration. However, some old PCI motherboards 2063e279b6c1SSam Ravnborg have BIOS bugs and may crash if this is done. Also, some embedded 2064e279b6c1SSam Ravnborg PCI-based systems don't have any BIOS at all. Linux can also try to 2065e279b6c1SSam Ravnborg detect the PCI hardware directly without using the BIOS. 2066e279b6c1SSam Ravnborg 2067e279b6c1SSam Ravnborg With this option, you can specify how Linux should detect the 2068e279b6c1SSam Ravnborg PCI devices. If you choose "BIOS", the BIOS will be used, 2069e279b6c1SSam Ravnborg if you choose "Direct", the BIOS won't be used, and if you 2070e279b6c1SSam Ravnborg choose "MMConfig", then PCI Express MMCONFIG will be used. 2071e279b6c1SSam Ravnborg If you choose "Any", the kernel will try MMCONFIG, then the 2072e279b6c1SSam Ravnborg direct access method and falls back to the BIOS if that doesn't 2073e279b6c1SSam Ravnborg work. If unsure, go with the default, which is "Any". 2074e279b6c1SSam Ravnborg 2075e279b6c1SSam Ravnborgconfig PCI_GOBIOS 2076e279b6c1SSam Ravnborg bool "BIOS" 2077e279b6c1SSam Ravnborg 2078e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG 2079e279b6c1SSam Ravnborg bool "MMConfig" 2080e279b6c1SSam Ravnborg 2081e279b6c1SSam Ravnborgconfig PCI_GODIRECT 2082e279b6c1SSam Ravnborg bool "Direct" 2083e279b6c1SSam Ravnborg 20843ef0e1f8SAndres Salomonconfig PCI_GOOLPC 208576fb6570SDaniel Drake bool "OLPC XO-1" 20863ef0e1f8SAndres Salomon depends on OLPC 20873ef0e1f8SAndres Salomon 20882bdd1b03SAndres Salomonconfig PCI_GOANY 20892bdd1b03SAndres Salomon bool "Any" 20902bdd1b03SAndres Salomon 2091e279b6c1SSam Ravnborgendchoice 2092e279b6c1SSam Ravnborg 2093e279b6c1SSam Ravnborgconfig PCI_BIOS 20943c2362e6SHarvey Harrison def_bool y 2095efefa6f6SIngo Molnar depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2096e279b6c1SSam Ravnborg 2097e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2098e279b6c1SSam Ravnborgconfig PCI_DIRECT 20993c2362e6SHarvey Harrison def_bool y 21000aba496fSShaohua Li depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2101e279b6c1SSam Ravnborg 2102e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 21033c2362e6SHarvey Harrison def_bool y 21045f0db7a2SFeng Tang depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2105e279b6c1SSam Ravnborg 21063ef0e1f8SAndres Salomonconfig PCI_OLPC 21072bdd1b03SAndres Salomon def_bool y 21082bdd1b03SAndres Salomon depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 21093ef0e1f8SAndres Salomon 2110b5401a96SAlex Nixonconfig PCI_XEN 2111b5401a96SAlex Nixon def_bool y 2112b5401a96SAlex Nixon depends on PCI && XEN 2113b5401a96SAlex Nixon select SWIOTLB_XEN 2114b5401a96SAlex Nixon 2115e279b6c1SSam Ravnborgconfig PCI_DOMAINS 21163c2362e6SHarvey Harrison def_bool y 2117e279b6c1SSam Ravnborg depends on PCI 2118e279b6c1SSam Ravnborg 2119e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 2120e279b6c1SSam Ravnborg bool "Support mmconfig PCI config space access" 2121e279b6c1SSam Ravnborg depends on X86_64 && PCI && ACPI 2122e279b6c1SSam Ravnborg 21233f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK 21246a108a14SDavid Rientjes bool "Read CNB20LE Host Bridge Windows" if EXPERT 21256ea30386SKees Cook depends on PCI 21263f6ea84aSIra W. Snyder help 21273f6ea84aSIra W. Snyder Read the PCI windows out of the CNB20LE host bridge. This allows 21283f6ea84aSIra W. Snyder PCI hotplug to work on systems with the CNB20LE chipset which do 21293f6ea84aSIra W. Snyder not have ACPI. 21303f6ea84aSIra W. Snyder 213164a5fed6SBjorn Helgaas There's no public spec for this chipset, and this functionality 213264a5fed6SBjorn Helgaas is known to be incomplete. 213364a5fed6SBjorn Helgaas 213464a5fed6SBjorn Helgaas You should say N unless you know you need this. 213564a5fed6SBjorn Helgaas 2136e279b6c1SSam Ravnborgsource "drivers/pci/pcie/Kconfig" 2137e279b6c1SSam Ravnborg 2138e279b6c1SSam Ravnborgsource "drivers/pci/Kconfig" 2139e279b6c1SSam Ravnborg 21401c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA. 2141e279b6c1SSam Ravnborgconfig ISA_DMA_API 21421c00f016SDavid Rientjes bool "ISA-style DMA support" if (X86_64 && EXPERT) 21431c00f016SDavid Rientjes default y 21441c00f016SDavid Rientjes help 21451c00f016SDavid Rientjes Enables ISA-style DMA support for devices requiring such controllers. 21461c00f016SDavid Rientjes If unsure, say Y. 2147e279b6c1SSam Ravnborg 2148e279b6c1SSam Ravnborgif X86_32 2149e279b6c1SSam Ravnborg 2150e279b6c1SSam Ravnborgconfig ISA 2151e279b6c1SSam Ravnborg bool "ISA support" 21528f9ca475SIngo Molnar ---help--- 2153e279b6c1SSam Ravnborg Find out whether you have ISA slots on your motherboard. ISA is the 2154e279b6c1SSam Ravnborg name of a bus system, i.e. the way the CPU talks to the other stuff 2155e279b6c1SSam Ravnborg inside your box. Other bus systems are PCI, EISA, MicroChannel 2156e279b6c1SSam Ravnborg (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2157e279b6c1SSam Ravnborg newer boards don't support it. If you have ISA, say Y, otherwise N. 2158e279b6c1SSam Ravnborg 2159e279b6c1SSam Ravnborgconfig EISA 2160e279b6c1SSam Ravnborg bool "EISA support" 2161e279b6c1SSam Ravnborg depends on ISA 2162e279b6c1SSam Ravnborg ---help--- 2163e279b6c1SSam Ravnborg The Extended Industry Standard Architecture (EISA) bus was 2164e279b6c1SSam Ravnborg developed as an open alternative to the IBM MicroChannel bus. 2165e279b6c1SSam Ravnborg 2166e279b6c1SSam Ravnborg The EISA bus provided some of the features of the IBM MicroChannel 2167e279b6c1SSam Ravnborg bus while maintaining backward compatibility with cards made for 2168e279b6c1SSam Ravnborg the older ISA bus. The EISA bus saw limited use between 1988 and 2169e279b6c1SSam Ravnborg 1995 when it was made obsolete by the PCI bus. 2170e279b6c1SSam Ravnborg 2171e279b6c1SSam Ravnborg Say Y here if you are building a kernel for an EISA-based machine. 2172e279b6c1SSam Ravnborg 2173e279b6c1SSam Ravnborg Otherwise, say N. 2174e279b6c1SSam Ravnborg 2175e279b6c1SSam Ravnborgsource "drivers/eisa/Kconfig" 2176e279b6c1SSam Ravnborg 2177e279b6c1SSam Ravnborgconfig SCx200 2178e279b6c1SSam Ravnborg tristate "NatSemi SCx200 support" 21798f9ca475SIngo Molnar ---help--- 2180e279b6c1SSam Ravnborg This provides basic support for National Semiconductor's 2181e279b6c1SSam Ravnborg (now AMD's) Geode processors. The driver probes for the 2182e279b6c1SSam Ravnborg PCI-IDs of several on-chip devices, so its a good dependency 2183e279b6c1SSam Ravnborg for other scx200_* drivers. 2184e279b6c1SSam Ravnborg 2185e279b6c1SSam Ravnborg If compiled as a module, the driver is named scx200. 2186e279b6c1SSam Ravnborg 2187e279b6c1SSam Ravnborgconfig SCx200HR_TIMER 2188e279b6c1SSam Ravnborg tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2189592913ecSJohn Stultz depends on SCx200 2190e279b6c1SSam Ravnborg default y 21918f9ca475SIngo Molnar ---help--- 2192e279b6c1SSam Ravnborg This driver provides a clocksource built upon the on-chip 2193e279b6c1SSam Ravnborg 27MHz high-resolution timer. Its also a workaround for 2194e279b6c1SSam Ravnborg NSC Geode SC-1100's buggy TSC, which loses time when the 2195e279b6c1SSam Ravnborg processor goes idle (as is done by the scheduler). The 2196e279b6c1SSam Ravnborg other workaround is idle=poll boot option. 2197e279b6c1SSam Ravnborg 21983ef0e1f8SAndres Salomonconfig OLPC 21993ef0e1f8SAndres Salomon bool "One Laptop Per Child support" 220054008979SThomas Gleixner depends on !X86_PAE 22013c554946SAndres Salomon select GPIOLIB 2202dc3119e7SThomas Gleixner select OF 220345bb1674SDaniel Drake select OF_PROMTREE 2204b4e51854SGrant Likely select IRQ_DOMAIN 22058f9ca475SIngo Molnar ---help--- 22063ef0e1f8SAndres Salomon Add support for detecting the unique features of the OLPC 22073ef0e1f8SAndres Salomon XO hardware. 22083ef0e1f8SAndres Salomon 2209a3128588SDaniel Drakeconfig OLPC_XO1_PM 2210a3128588SDaniel Drake bool "OLPC XO-1 Power Management" 221197c4cb71SDaniel Drake depends on OLPC && MFD_CS5535 && PM_SLEEP 2212a3128588SDaniel Drake select MFD_CORE 2213bf1ebf00SDaniel Drake ---help--- 221497c4cb71SDaniel Drake Add support for poweroff and suspend of the OLPC XO-1 laptop. 2215bf1ebf00SDaniel Drake 2216cfee9597SDaniel Drakeconfig OLPC_XO1_RTC 2217cfee9597SDaniel Drake bool "OLPC XO-1 Real Time Clock" 2218cfee9597SDaniel Drake depends on OLPC_XO1_PM && RTC_DRV_CMOS 2219cfee9597SDaniel Drake ---help--- 2220cfee9597SDaniel Drake Add support for the XO-1 real time clock, which can be used as a 2221cfee9597SDaniel Drake programmable wakeup source. 2222cfee9597SDaniel Drake 22237feda8e9SDaniel Drakeconfig OLPC_XO1_SCI 22247feda8e9SDaniel Drake bool "OLPC XO-1 SCI extras" 2225d8d01a63SDaniel Drake depends on OLPC && OLPC_XO1_PM 2226ed8e47feSRandy Dunlap depends on INPUT=y 2227d8d01a63SDaniel Drake select POWER_SUPPLY 22287feda8e9SDaniel Drake select GPIO_CS5535 22297feda8e9SDaniel Drake select MFD_CORE 22307feda8e9SDaniel Drake ---help--- 22317feda8e9SDaniel Drake Add support for SCI-based features of the OLPC XO-1 laptop: 22327bc74b3dSDaniel Drake - EC-driven system wakeups 22337feda8e9SDaniel Drake - Power button 22347bc74b3dSDaniel Drake - Ebook switch 22352cf2baeaSDaniel Drake - Lid switch 2236e1040ac6SDaniel Drake - AC adapter status updates 2237e1040ac6SDaniel Drake - Battery status updates 22387feda8e9SDaniel Drake 2239a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI 2240a0f30f59SDaniel Drake bool "OLPC XO-1.5 SCI extras" 2241d8d01a63SDaniel Drake depends on OLPC && ACPI 2242d8d01a63SDaniel Drake select POWER_SUPPLY 2243a0f30f59SDaniel Drake ---help--- 2244a0f30f59SDaniel Drake Add support for SCI-based features of the OLPC XO-1.5 laptop: 2245a0f30f59SDaniel Drake - EC-driven system wakeups 2246a0f30f59SDaniel Drake - AC adapter status updates 2247a0f30f59SDaniel Drake - Battery status updates 2248e279b6c1SSam Ravnborg 2249d4f3e350SEd Wildgooseconfig ALIX 2250d4f3e350SEd Wildgoose bool "PCEngines ALIX System Support (LED setup)" 2251d4f3e350SEd Wildgoose select GPIOLIB 2252d4f3e350SEd Wildgoose ---help--- 2253d4f3e350SEd Wildgoose This option enables system support for the PCEngines ALIX. 2254d4f3e350SEd Wildgoose At present this just sets up LEDs for GPIO control on 2255d4f3e350SEd Wildgoose ALIX2/3/6 boards. However, other system specific setup should 2256d4f3e350SEd Wildgoose get added here. 2257d4f3e350SEd Wildgoose 2258d4f3e350SEd Wildgoose Note: You must still enable the drivers for GPIO and LED support 2259d4f3e350SEd Wildgoose (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2260d4f3e350SEd Wildgoose 2261d4f3e350SEd Wildgoose Note: You have to set alix.force=1 for boards with Award BIOS. 2262d4f3e350SEd Wildgoose 2263da4e3302SPhilip Prindevilleconfig NET5501 2264da4e3302SPhilip Prindeville bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2265da4e3302SPhilip Prindeville select GPIOLIB 2266da4e3302SPhilip Prindeville ---help--- 2267da4e3302SPhilip Prindeville This option enables system support for the Soekris Engineering net5501. 2268da4e3302SPhilip Prindeville 22693197059aSPhilip A. Prindevilleconfig GEOS 22703197059aSPhilip A. Prindeville bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 22713197059aSPhilip A. Prindeville select GPIOLIB 22723197059aSPhilip A. Prindeville depends on DMI 22733197059aSPhilip A. Prindeville ---help--- 22743197059aSPhilip A. Prindeville This option enables system support for the Traverse Technologies GEOS. 22753197059aSPhilip A. Prindeville 22767d029125SVivien Didelotconfig TS5500 22777d029125SVivien Didelot bool "Technologic Systems TS-5500 platform support" 22787d029125SVivien Didelot depends on MELAN 22797d029125SVivien Didelot select CHECK_SIGNATURE 22807d029125SVivien Didelot select NEW_LEDS 22817d029125SVivien Didelot select LEDS_CLASS 22827d029125SVivien Didelot ---help--- 22837d029125SVivien Didelot This option enables system support for the Technologic Systems TS-5500. 22847d029125SVivien Didelot 2285e279b6c1SSam Ravnborgendif # X86_32 2286e279b6c1SSam Ravnborg 228723ac4ae8SAndreas Herrmannconfig AMD_NB 2288e279b6c1SSam Ravnborg def_bool y 22890e152cd7SBorislav Petkov depends on CPU_SUP_AMD && PCI 2290e279b6c1SSam Ravnborg 2291e279b6c1SSam Ravnborgsource "drivers/pcmcia/Kconfig" 2292e279b6c1SSam Ravnborg 2293e279b6c1SSam Ravnborgsource "drivers/pci/hotplug/Kconfig" 2294e279b6c1SSam Ravnborg 2295388b78adSAlexandre Bounineconfig RAPIDIO 2296fdf90abcSAlexandre Bounine tristate "RapidIO support" 2297388b78adSAlexandre Bounine depends on PCI 2298388b78adSAlexandre Bounine default n 2299388b78adSAlexandre Bounine help 2300fdf90abcSAlexandre Bounine If enabled this option will include drivers and the core 2301388b78adSAlexandre Bounine infrastructure code to support RapidIO interconnect devices. 2302388b78adSAlexandre Bounine 2303388b78adSAlexandre Bouninesource "drivers/rapidio/Kconfig" 2304388b78adSAlexandre Bounine 2305e3263ab3SDavid Herrmannconfig X86_SYSFB 2306e3263ab3SDavid Herrmann bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2307e3263ab3SDavid Herrmann help 2308e3263ab3SDavid Herrmann Firmwares often provide initial graphics framebuffers so the BIOS, 2309e3263ab3SDavid Herrmann bootloader or kernel can show basic video-output during boot for 2310e3263ab3SDavid Herrmann user-guidance and debugging. Historically, x86 used the VESA BIOS 2311e3263ab3SDavid Herrmann Extensions and EFI-framebuffers for this, which are mostly limited 2312e3263ab3SDavid Herrmann to x86. 2313e3263ab3SDavid Herrmann This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2314e3263ab3SDavid Herrmann framebuffers so the new generic system-framebuffer drivers can be 2315e3263ab3SDavid Herrmann used on x86. If the framebuffer is not compatible with the generic 2316e3263ab3SDavid Herrmann modes, it is adverticed as fallback platform framebuffer so legacy 2317e3263ab3SDavid Herrmann drivers like efifb, vesafb and uvesafb can pick it up. 2318e3263ab3SDavid Herrmann If this option is not selected, all system framebuffers are always 2319e3263ab3SDavid Herrmann marked as fallback platform framebuffers as usual. 2320e3263ab3SDavid Herrmann 2321e3263ab3SDavid Herrmann Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2322e3263ab3SDavid Herrmann not be able to pick up generic system framebuffers if this option 2323e3263ab3SDavid Herrmann is selected. You are highly encouraged to enable simplefb as 2324e3263ab3SDavid Herrmann replacement if you select this option. simplefb can correctly deal 2325e3263ab3SDavid Herrmann with generic system framebuffers. But you should still keep vesafb 2326e3263ab3SDavid Herrmann and others enabled as fallback if a system framebuffer is 2327e3263ab3SDavid Herrmann incompatible with simplefb. 2328e3263ab3SDavid Herrmann 2329e3263ab3SDavid Herrmann If unsure, say Y. 2330e3263ab3SDavid Herrmann 2331e279b6c1SSam Ravnborgendmenu 2332e279b6c1SSam Ravnborg 2333e279b6c1SSam Ravnborg 2334e279b6c1SSam Ravnborgmenu "Executable file formats / Emulations" 2335e279b6c1SSam Ravnborg 2336e279b6c1SSam Ravnborgsource "fs/Kconfig.binfmt" 2337e279b6c1SSam Ravnborg 2338e279b6c1SSam Ravnborgconfig IA32_EMULATION 2339e279b6c1SSam Ravnborg bool "IA32 Emulation" 2340e279b6c1SSam Ravnborg depends on X86_64 2341d1603990SRandy Dunlap select BINFMT_ELF 2342a97f52e6SRoland McGrath select COMPAT_BINFMT_ELF 2343af1839ebSCatalin Marinas select HAVE_UID16 23448f9ca475SIngo Molnar ---help--- 23455fd92e65SH. J. Lu Include code to run legacy 32-bit programs under a 23465fd92e65SH. J. Lu 64-bit kernel. You should likely turn this on, unless you're 23475fd92e65SH. J. Lu 100% sure that you don't have any 32-bit programs left. 2348e279b6c1SSam Ravnborg 2349e279b6c1SSam Ravnborgconfig IA32_AOUT 2350e279b6c1SSam Ravnborg tristate "IA32 a.out support" 23516b213e1bSDavid Woodhouse depends on IA32_EMULATION 23528f9ca475SIngo Molnar ---help--- 2353e279b6c1SSam Ravnborg Support old a.out binaries in the 32bit emulation. 2354e279b6c1SSam Ravnborg 23550bf62763SH. Peter Anvinconfig X86_X32 23566ea30386SKees Cook bool "x32 ABI for 64-bit mode" 23576ea30386SKees Cook depends on X86_64 && IA32_EMULATION 23585fd92e65SH. J. Lu ---help--- 23595fd92e65SH. J. Lu Include code to run binaries for the x32 native 32-bit ABI 23605fd92e65SH. J. Lu for 64-bit processors. An x32 process gets access to the 23615fd92e65SH. J. Lu full 64-bit register file and wide data path while leaving 23625fd92e65SH. J. Lu pointers at 32 bits for smaller memory footprint. 23635fd92e65SH. J. Lu 23645fd92e65SH. J. Lu You will need a recent binutils (2.22 or later) with 23655fd92e65SH. J. Lu elf32_x86_64 support enabled to compile a kernel with this 23665fd92e65SH. J. Lu option set. 23675fd92e65SH. J. Lu 2368e279b6c1SSam Ravnborgconfig COMPAT 23693c2362e6SHarvey Harrison def_bool y 23700bf62763SH. Peter Anvin depends on IA32_EMULATION || X86_X32 237148b25c43SChris Metcalf select ARCH_WANT_OLD_COMPAT_IPC 2372e279b6c1SSam Ravnborg 23733120e25eSJan Beulichif COMPAT 2374e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT 23753120e25eSJan Beulich def_bool y 2376e279b6c1SSam Ravnborg 2377e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT 23783c2362e6SHarvey Harrison def_bool y 23793120e25eSJan Beulich depends on SYSVIPC 2380e279b6c1SSam Ravnborg 2381ee009e4aSDavid Howellsconfig KEYS_COMPAT 23823120e25eSJan Beulich def_bool y 23833120e25eSJan Beulich depends on KEYS 23843120e25eSJan Beulichendif 2385ee009e4aSDavid Howells 2386e279b6c1SSam Ravnborgendmenu 2387e279b6c1SSam Ravnborg 2388e279b6c1SSam Ravnborg 2389e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP 2390e5beae16SKeith Packard def_bool y 2391e5beae16SKeith Packard depends on X86_32 2392e5beae16SKeith Packard 23934692d77fSAlessandro Rubiniconfig X86_DEV_DMA_OPS 23944692d77fSAlessandro Rubini bool 239583125a3aSAlessandro Rubini depends on X86_64 || STA2X11 23964692d77fSAlessandro Rubini 2397f7219a53SAlessandro Rubiniconfig X86_DMA_REMAP 2398f7219a53SAlessandro Rubini bool 239983125a3aSAlessandro Rubini depends on STA2X11 2400f7219a53SAlessandro Rubini 240146184415SDavid E. Boxconfig IOSF_MBI 24026b8f0c87SDavid E. Box tristate 24036b8f0c87SDavid E. Box default m 240446184415SDavid E. Box depends on PCI 240546184415SDavid E. Box 2406*93e5eaddSLi, Aubreyconfig PMC_ATOM 2407*93e5eaddSLi, Aubrey def_bool y 2408*93e5eaddSLi, Aubrey depends on PCI 2409*93e5eaddSLi, Aubrey 2410e279b6c1SSam Ravnborgsource "net/Kconfig" 2411e279b6c1SSam Ravnborg 2412e279b6c1SSam Ravnborgsource "drivers/Kconfig" 2413e279b6c1SSam Ravnborg 2414e279b6c1SSam Ravnborgsource "drivers/firmware/Kconfig" 2415e279b6c1SSam Ravnborg 2416e279b6c1SSam Ravnborgsource "fs/Kconfig" 2417e279b6c1SSam Ravnborg 2418e279b6c1SSam Ravnborgsource "arch/x86/Kconfig.debug" 2419e279b6c1SSam Ravnborg 2420e279b6c1SSam Ravnborgsource "security/Kconfig" 2421e279b6c1SSam Ravnborg 2422e279b6c1SSam Ravnborgsource "crypto/Kconfig" 2423e279b6c1SSam Ravnborg 2424edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig" 2425edf88417SAvi Kivity 2426e279b6c1SSam Ravnborgsource "lib/Kconfig" 2427