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1 # Select 32 or 64 bit
2 config 64BIT
3 bool "64-bit kernel" if ARCH = "x86"
4 default ARCH != "i386"
5 ---help---
6 Say yes to build a 64-bit kernel - formerly known as x86_64
7 Say no to build a 32-bit kernel - formerly known as i386
8
9 config X86_32
10 def_bool y
11 depends on !64BIT
12
13 config X86_64
14 def_bool y
15 depends on 64BIT
16
17 ### Arch settings
18 config X86
19 def_bool y
20 select ACPI_LEGACY_TABLES_LOOKUP if ACPI
21 select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
22 select ANON_INODES
23 select ARCH_CLOCKSOURCE_DATA
24 select ARCH_DISCARD_MEMBLOCK
25 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
26 select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS
27 select ARCH_HAS_DEVMEM_IS_ALLOWED
28 select ARCH_HAS_ELF_RANDOMIZE
29 select ARCH_HAS_FAST_MULTIPLIER
30 select ARCH_HAS_GCOV_PROFILE_ALL
31 select ARCH_HAS_PMEM_API if X86_64
32 select ARCH_HAS_MMIO_FLUSH
33 select ARCH_HAS_SG_CHAIN
34 select ARCH_HAS_UBSAN_SANITIZE_ALL
35 select ARCH_HAVE_NMI_SAFE_CMPXCHG
36 select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
37 select ARCH_MIGHT_HAVE_PC_PARPORT
38 select ARCH_MIGHT_HAVE_PC_SERIO
39 select ARCH_SUPPORTS_ATOMIC_RMW
40 select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT
41 select ARCH_SUPPORTS_INT128 if X86_64
42 select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
43 select ARCH_USE_BUILTIN_BSWAP
44 select ARCH_USE_CMPXCHG_LOCKREF if X86_64
45 select ARCH_USE_QUEUED_RWLOCKS
46 select ARCH_USE_QUEUED_SPINLOCKS
47 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP
48 select ARCH_WANTS_DYNAMIC_TASK_STRUCT
49 select ARCH_WANT_FRAME_POINTERS
50 select ARCH_WANT_IPC_PARSE_VERSION if X86_32
51 select ARCH_WANT_OPTIONAL_GPIOLIB
52 select BUILDTIME_EXTABLE_SORT
53 select CLKEVT_I8253
54 select CLKSRC_I8253 if X86_32
55 select CLOCKSOURCE_VALIDATE_LAST_CYCLE
56 select CLOCKSOURCE_WATCHDOG
57 select CLONE_BACKWARDS if X86_32
58 select COMPAT_OLD_SIGACTION if IA32_EMULATION
59 select DCACHE_WORD_ACCESS
60 select EDAC_ATOMIC_SCRUB
61 select EDAC_SUPPORT
62 select GENERIC_CLOCKEVENTS
63 select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
64 select GENERIC_CLOCKEVENTS_MIN_ADJUST
65 select GENERIC_CMOS_UPDATE
66 select GENERIC_CPU_AUTOPROBE
67 select GENERIC_EARLY_IOREMAP
68 select GENERIC_FIND_FIRST_BIT
69 select GENERIC_IOMAP
70 select GENERIC_IRQ_PROBE
71 select GENERIC_IRQ_SHOW
72 select GENERIC_PENDING_IRQ if SMP
73 select GENERIC_SMP_IDLE_THREAD
74 select GENERIC_STRNCPY_FROM_USER
75 select GENERIC_STRNLEN_USER
76 select GENERIC_TIME_VSYSCALL
77 select HAVE_ACPI_APEI if ACPI
78 select HAVE_ACPI_APEI_NMI if ACPI
79 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
80 select HAVE_AOUT if X86_32
81 select HAVE_ARCH_AUDITSYSCALL
82 select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
83 select HAVE_ARCH_JUMP_LABEL
84 select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP
85 select HAVE_ARCH_KGDB
86 select HAVE_ARCH_KMEMCHECK
87 select HAVE_ARCH_MMAP_RND_BITS if MMU
88 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
89 select HAVE_ARCH_SECCOMP_FILTER
90 select HAVE_ARCH_SOFT_DIRTY if X86_64
91 select HAVE_ARCH_TRACEHOOK
92 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
93 select HAVE_BPF_JIT if X86_64
94 select HAVE_CC_STACKPROTECTOR
95 select HAVE_CMPXCHG_DOUBLE
96 select HAVE_CMPXCHG_LOCAL
97 select HAVE_CONTEXT_TRACKING if X86_64
98 select HAVE_COPY_THREAD_TLS
99 select HAVE_C_RECORDMCOUNT
100 select HAVE_DEBUG_KMEMLEAK
101 select HAVE_DEBUG_STACKOVERFLOW
102 select HAVE_DMA_API_DEBUG
103 select HAVE_DMA_CONTIGUOUS
104 select HAVE_DYNAMIC_FTRACE
105 select HAVE_DYNAMIC_FTRACE_WITH_REGS
106 select HAVE_EFFICIENT_UNALIGNED_ACCESS
107 select HAVE_FENTRY if X86_64
108 select HAVE_FTRACE_MCOUNT_RECORD
109 select HAVE_FUNCTION_GRAPH_FP_TEST
110 select HAVE_FUNCTION_GRAPH_TRACER
111 select HAVE_FUNCTION_TRACER
112 select HAVE_GENERIC_DMA_COHERENT if X86_32
113 select HAVE_HW_BREAKPOINT
114 select HAVE_IDE
115 select HAVE_IOREMAP_PROT
116 select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
117 select HAVE_IRQ_TIME_ACCOUNTING
118 select HAVE_KERNEL_BZIP2
119 select HAVE_KERNEL_GZIP
120 select HAVE_KERNEL_LZ4
121 select HAVE_KERNEL_LZMA
122 select HAVE_KERNEL_LZO
123 select HAVE_KERNEL_XZ
124 select HAVE_KPROBES
125 select HAVE_KPROBES_ON_FTRACE
126 select HAVE_KRETPROBES
127 select HAVE_KVM
128 select HAVE_LIVEPATCH if X86_64
129 select HAVE_MEMBLOCK
130 select HAVE_MEMBLOCK_NODE_MAP
131 select HAVE_MIXED_BREAKPOINTS_REGS
132 select HAVE_OPROFILE
133 select HAVE_OPTPROBES
134 select HAVE_PCSPKR_PLATFORM
135 select HAVE_PERF_EVENTS
136 select HAVE_PERF_EVENTS_NMI
137 select HAVE_PERF_REGS
138 select HAVE_PERF_USER_STACK_DUMP
139 select HAVE_REGS_AND_STACK_ACCESS_API
140 select HAVE_SYSCALL_TRACEPOINTS
141 select HAVE_UID16 if X86_32 || IA32_EMULATION
142 select HAVE_UNSTABLE_SCHED_CLOCK
143 select HAVE_USER_RETURN_NOTIFIER
144 select IRQ_FORCED_THREADING
145 select MODULES_USE_ELF_RELA if X86_64
146 select MODULES_USE_ELF_REL if X86_32
147 select OLD_SIGACTION if X86_32
148 select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION
149 select PERF_EVENTS
150 select RTC_LIB
151 select SPARSE_IRQ
152 select SRCU
153 select SYSCTL_EXCEPTION_TRACE
154 select USER_STACKTRACE_SUPPORT
155 select VIRT_TO_BUS
156 select X86_DEV_DMA_OPS if X86_64
157 select X86_FEATURE_NAMES if PROC_FS
158
159 config INSTRUCTION_DECODER
160 def_bool y
161 depends on KPROBES || PERF_EVENTS || UPROBES
162
163 config PERF_EVENTS_INTEL_UNCORE
164 def_bool y
165 depends on PERF_EVENTS && CPU_SUP_INTEL && PCI
166
167 config OUTPUT_FORMAT
168 string
169 default "elf32-i386" if X86_32
170 default "elf64-x86-64" if X86_64
171
172 config ARCH_DEFCONFIG
173 string
174 default "arch/x86/configs/i386_defconfig" if X86_32
175 default "arch/x86/configs/x86_64_defconfig" if X86_64
176
177 config LOCKDEP_SUPPORT
178 def_bool y
179
180 config STACKTRACE_SUPPORT
181 def_bool y
182
183 config MMU
184 def_bool y
185
186 config ARCH_MMAP_RND_BITS_MIN
187 default 28 if 64BIT
188 default 8
189
190 config ARCH_MMAP_RND_BITS_MAX
191 default 32 if 64BIT
192 default 16
193
194 config ARCH_MMAP_RND_COMPAT_BITS_MIN
195 default 8
196
197 config ARCH_MMAP_RND_COMPAT_BITS_MAX
198 default 16
199
200 config SBUS
201 bool
202
203 config NEED_DMA_MAP_STATE
204 def_bool y
205 depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB
206
207 config NEED_SG_DMA_LENGTH
208 def_bool y
209
210 config GENERIC_ISA_DMA
211 def_bool y
212 depends on ISA_DMA_API
213
214 config GENERIC_BUG
215 def_bool y
216 depends on BUG
217 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
218
219 config GENERIC_BUG_RELATIVE_POINTERS
220 bool
221
222 config GENERIC_HWEIGHT
223 def_bool y
224
225 config ARCH_MAY_HAVE_PC_FDC
226 def_bool y
227 depends on ISA_DMA_API
228
229 config RWSEM_XCHGADD_ALGORITHM
230 def_bool y
231
232 config GENERIC_CALIBRATE_DELAY
233 def_bool y
234
235 config ARCH_HAS_CPU_RELAX
236 def_bool y
237
238 config ARCH_HAS_CACHE_LINE_SIZE
239 def_bool y
240
241 config HAVE_SETUP_PER_CPU_AREA
242 def_bool y
243
244 config NEED_PER_CPU_EMBED_FIRST_CHUNK
245 def_bool y
246
247 config NEED_PER_CPU_PAGE_FIRST_CHUNK
248 def_bool y
249
250 config ARCH_HIBERNATION_POSSIBLE
251 def_bool y
252
253 config ARCH_SUSPEND_POSSIBLE
254 def_bool y
255
256 config ARCH_WANT_HUGE_PMD_SHARE
257 def_bool y
258
259 config ARCH_WANT_GENERAL_HUGETLB
260 def_bool y
261
262 config ZONE_DMA32
263 def_bool y if X86_64
264
265 config AUDIT_ARCH
266 def_bool y if X86_64
267
268 config ARCH_SUPPORTS_OPTIMIZED_INLINING
269 def_bool y
270
271 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
272 def_bool y
273
274 config KASAN_SHADOW_OFFSET
275 hex
276 depends on KASAN
277 default 0xdffffc0000000000
278
279 config HAVE_INTEL_TXT
280 def_bool y
281 depends on INTEL_IOMMU && ACPI
282
283 config X86_32_SMP
284 def_bool y
285 depends on X86_32 && SMP
286
287 config X86_64_SMP
288 def_bool y
289 depends on X86_64 && SMP
290
291 config X86_32_LAZY_GS
292 def_bool y
293 depends on X86_32 && !CC_STACKPROTECTOR
294
295 config ARCH_HWEIGHT_CFLAGS
296 string
297 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
298 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
299
300 config ARCH_SUPPORTS_UPROBES
301 def_bool y
302
303 config FIX_EARLYCON_MEM
304 def_bool y
305
306 config PGTABLE_LEVELS
307 int
308 default 4 if X86_64
309 default 3 if X86_PAE
310 default 2
311
312 source "init/Kconfig"
313 source "kernel/Kconfig.freezer"
314
315 menu "Processor type and features"
316
317 config ZONE_DMA
318 bool "DMA memory allocation support" if EXPERT
319 default y
320 help
321 DMA memory allocation support allows devices with less than 32-bit
322 addressing to allocate within the first 16MB of address space.
323 Disable if no such devices will be used.
324
325 If unsure, say Y.
326
327 config SMP
328 bool "Symmetric multi-processing support"
329 ---help---
330 This enables support for systems with more than one CPU. If you have
331 a system with only one CPU, say N. If you have a system with more
332 than one CPU, say Y.
333
334 If you say N here, the kernel will run on uni- and multiprocessor
335 machines, but will use only one CPU of a multiprocessor machine. If
336 you say Y here, the kernel will run on many, but not all,
337 uniprocessor machines. On a uniprocessor machine, the kernel
338 will run faster if you say N here.
339
340 Note that if you say Y here and choose architecture "586" or
341 "Pentium" under "Processor family", the kernel will not work on 486
342 architectures. Similarly, multiprocessor kernels for the "PPro"
343 architecture may not work on all Pentium based boards.
344
345 People using multiprocessor machines who say Y here should also say
346 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
347 Management" code will be disabled if you say Y here.
348
349 See also <file:Documentation/x86/i386/IO-APIC.txt>,
350 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
351 <http://www.tldp.org/docs.html#howto>.
352
353 If you don't know what to do here, say N.
354
355 config X86_FEATURE_NAMES
356 bool "Processor feature human-readable names" if EMBEDDED
357 default y
358 ---help---
359 This option compiles in a table of x86 feature bits and corresponding
360 names. This is required to support /proc/cpuinfo and a few kernel
361 messages. You can disable this to save space, at the expense of
362 making those few kernel messages show numeric feature bits instead.
363
364 If in doubt, say Y.
365
366 config X86_FAST_FEATURE_TESTS
367 bool "Fast CPU feature tests" if EMBEDDED
368 default y
369 ---help---
370 Some fast-paths in the kernel depend on the capabilities of the CPU.
371 Say Y here for the kernel to patch in the appropriate code at runtime
372 based on the capabilities of the CPU. The infrastructure for patching
373 code at runtime takes up some additional space; space-constrained
374 embedded systems may wish to say N here to produce smaller, slightly
375 slower code.
376
377 config X86_X2APIC
378 bool "Support x2apic"
379 depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
380 ---help---
381 This enables x2apic support on CPUs that have this feature.
382
383 This allows 32-bit apic IDs (so it can support very large systems),
384 and accesses the local apic via MSRs not via mmio.
385
386 If you don't know what to do here, say N.
387
388 config X86_MPPARSE
389 bool "Enable MPS table" if ACPI || SFI
390 default y
391 depends on X86_LOCAL_APIC
392 ---help---
393 For old smp systems that do not have proper acpi support. Newer systems
394 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
395
396 config X86_BIGSMP
397 bool "Support for big SMP systems with more than 8 CPUs"
398 depends on X86_32 && SMP
399 ---help---
400 This option is needed for the systems that have more than 8 CPUs
401
402 config GOLDFISH
403 def_bool y
404 depends on X86_GOLDFISH
405
406 if X86_32
407 config X86_EXTENDED_PLATFORM
408 bool "Support for extended (non-PC) x86 platforms"
409 default y
410 ---help---
411 If you disable this option then the kernel will only support
412 standard PC platforms. (which covers the vast majority of
413 systems out there.)
414
415 If you enable this option then you'll be able to select support
416 for the following (non-PC) 32 bit x86 platforms:
417 Goldfish (Android emulator)
418 AMD Elan
419 RDC R-321x SoC
420 SGI 320/540 (Visual Workstation)
421 STA2X11-based (e.g. Northville)
422 Moorestown MID devices
423
424 If you have one of these systems, or if you want to build a
425 generic distribution kernel, say Y here - otherwise say N.
426 endif
427
428 if X86_64
429 config X86_EXTENDED_PLATFORM
430 bool "Support for extended (non-PC) x86 platforms"
431 default y
432 ---help---
433 If you disable this option then the kernel will only support
434 standard PC platforms. (which covers the vast majority of
435 systems out there.)
436
437 If you enable this option then you'll be able to select support
438 for the following (non-PC) 64 bit x86 platforms:
439 Numascale NumaChip
440 ScaleMP vSMP
441 SGI Ultraviolet
442
443 If you have one of these systems, or if you want to build a
444 generic distribution kernel, say Y here - otherwise say N.
445 endif
446 # This is an alphabetically sorted list of 64 bit extended platforms
447 # Please maintain the alphabetic order if and when there are additions
448 config X86_NUMACHIP
449 bool "Numascale NumaChip"
450 depends on X86_64
451 depends on X86_EXTENDED_PLATFORM
452 depends on NUMA
453 depends on SMP
454 depends on X86_X2APIC
455 depends on PCI_MMCONFIG
456 ---help---
457 Adds support for Numascale NumaChip large-SMP systems. Needed to
458 enable more than ~168 cores.
459 If you don't have one of these, you should say N here.
460
461 config X86_VSMP
462 bool "ScaleMP vSMP"
463 select HYPERVISOR_GUEST
464 select PARAVIRT
465 depends on X86_64 && PCI
466 depends on X86_EXTENDED_PLATFORM
467 depends on SMP
468 ---help---
469 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
470 supposed to run on these EM64T-based machines. Only choose this option
471 if you have one of these machines.
472
473 config X86_UV
474 bool "SGI Ultraviolet"
475 depends on X86_64
476 depends on X86_EXTENDED_PLATFORM
477 depends on NUMA
478 depends on X86_X2APIC
479 depends on PCI
480 ---help---
481 This option is needed in order to support SGI Ultraviolet systems.
482 If you don't have one of these, you should say N here.
483
484 # Following is an alphabetically sorted list of 32 bit extended platforms
485 # Please maintain the alphabetic order if and when there are additions
486
487 config X86_GOLDFISH
488 bool "Goldfish (Virtual Platform)"
489 depends on X86_EXTENDED_PLATFORM
490 ---help---
491 Enable support for the Goldfish virtual platform used primarily
492 for Android development. Unless you are building for the Android
493 Goldfish emulator say N here.
494
495 config X86_INTEL_CE
496 bool "CE4100 TV platform"
497 depends on PCI
498 depends on PCI_GODIRECT
499 depends on X86_IO_APIC
500 depends on X86_32
501 depends on X86_EXTENDED_PLATFORM
502 select X86_REBOOTFIXUPS
503 select OF
504 select OF_EARLY_FLATTREE
505 ---help---
506 Select for the Intel CE media processor (CE4100) SOC.
507 This option compiles in support for the CE4100 SOC for settop
508 boxes and media devices.
509
510 config X86_INTEL_MID
511 bool "Intel MID platform support"
512 depends on X86_EXTENDED_PLATFORM
513 depends on X86_PLATFORM_DEVICES
514 depends on PCI
515 depends on X86_64 || (PCI_GOANY && X86_32)
516 depends on X86_IO_APIC
517 select SFI
518 select I2C
519 select DW_APB_TIMER
520 select APB_TIMER
521 select INTEL_SCU_IPC
522 select MFD_INTEL_MSIC
523 ---help---
524 Select to build a kernel capable of supporting Intel MID (Mobile
525 Internet Device) platform systems which do not have the PCI legacy
526 interfaces. If you are building for a PC class system say N here.
527
528 Intel MID platforms are based on an Intel processor and chipset which
529 consume less power than most of the x86 derivatives.
530
531 config X86_INTEL_QUARK
532 bool "Intel Quark platform support"
533 depends on X86_32
534 depends on X86_EXTENDED_PLATFORM
535 depends on X86_PLATFORM_DEVICES
536 depends on X86_TSC
537 depends on PCI
538 depends on PCI_GOANY
539 depends on X86_IO_APIC
540 select IOSF_MBI
541 select INTEL_IMR
542 select COMMON_CLK
543 ---help---
544 Select to include support for Quark X1000 SoC.
545 Say Y here if you have a Quark based system such as the Arduino
546 compatible Intel Galileo.
547
548 config X86_INTEL_LPSS
549 bool "Intel Low Power Subsystem Support"
550 depends on X86 && ACPI
551 select COMMON_CLK
552 select PINCTRL
553 select IOSF_MBI
554 ---help---
555 Select to build support for Intel Low Power Subsystem such as
556 found on Intel Lynxpoint PCH. Selecting this option enables
557 things like clock tree (common clock framework) and pincontrol
558 which are needed by the LPSS peripheral drivers.
559
560 config X86_AMD_PLATFORM_DEVICE
561 bool "AMD ACPI2Platform devices support"
562 depends on ACPI
563 select COMMON_CLK
564 select PINCTRL
565 ---help---
566 Select to interpret AMD specific ACPI device to platform device
567 such as I2C, UART, GPIO found on AMD Carrizo and later chipsets.
568 I2C and UART depend on COMMON_CLK to set clock. GPIO driver is
569 implemented under PINCTRL subsystem.
570
571 config IOSF_MBI
572 tristate "Intel SoC IOSF Sideband support for SoC platforms"
573 depends on PCI
574 ---help---
575 This option enables sideband register access support for Intel SoC
576 platforms. On these platforms the IOSF sideband is used in lieu of
577 MSR's for some register accesses, mostly but not limited to thermal
578 and power. Drivers may query the availability of this device to
579 determine if they need the sideband in order to work on these
580 platforms. The sideband is available on the following SoC products.
581 This list is not meant to be exclusive.
582 - BayTrail
583 - Braswell
584 - Quark
585
586 You should say Y if you are running a kernel on one of these SoC's.
587
588 config IOSF_MBI_DEBUG
589 bool "Enable IOSF sideband access through debugfs"
590 depends on IOSF_MBI && DEBUG_FS
591 ---help---
592 Select this option to expose the IOSF sideband access registers (MCR,
593 MDR, MCRX) through debugfs to write and read register information from
594 different units on the SoC. This is most useful for obtaining device
595 state information for debug and analysis. As this is a general access
596 mechanism, users of this option would have specific knowledge of the
597 device they want to access.
598
599 If you don't require the option or are in doubt, say N.
600
601 config X86_RDC321X
602 bool "RDC R-321x SoC"
603 depends on X86_32
604 depends on X86_EXTENDED_PLATFORM
605 select M486
606 select X86_REBOOTFIXUPS
607 ---help---
608 This option is needed for RDC R-321x system-on-chip, also known
609 as R-8610-(G).
610 If you don't have one of these chips, you should say N here.
611
612 config X86_32_NON_STANDARD
613 bool "Support non-standard 32-bit SMP architectures"
614 depends on X86_32 && SMP
615 depends on X86_EXTENDED_PLATFORM
616 ---help---
617 This option compiles in the bigsmp and STA2X11 default
618 subarchitectures. It is intended for a generic binary
619 kernel. If you select them all, kernel will probe it one by
620 one and will fallback to default.
621
622 # Alphabetically sorted list of Non standard 32 bit platforms
623
624 config X86_SUPPORTS_MEMORY_FAILURE
625 def_bool y
626 # MCE code calls memory_failure():
627 depends on X86_MCE
628 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
629 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
630 depends on X86_64 || !SPARSEMEM
631 select ARCH_SUPPORTS_MEMORY_FAILURE
632
633 config STA2X11
634 bool "STA2X11 Companion Chip Support"
635 depends on X86_32_NON_STANDARD && PCI
636 select X86_DEV_DMA_OPS
637 select X86_DMA_REMAP
638 select SWIOTLB
639 select MFD_STA2X11
640 select ARCH_REQUIRE_GPIOLIB
641 default n
642 ---help---
643 This adds support for boards based on the STA2X11 IO-Hub,
644 a.k.a. "ConneXt". The chip is used in place of the standard
645 PC chipset, so all "standard" peripherals are missing. If this
646 option is selected the kernel will still be able to boot on
647 standard PC machines.
648
649 config X86_32_IRIS
650 tristate "Eurobraille/Iris poweroff module"
651 depends on X86_32
652 ---help---
653 The Iris machines from EuroBraille do not have APM or ACPI support
654 to shut themselves down properly. A special I/O sequence is
655 needed to do so, which is what this module does at
656 kernel shutdown.
657
658 This is only for Iris machines from EuroBraille.
659
660 If unused, say N.
661
662 config SCHED_OMIT_FRAME_POINTER
663 def_bool y
664 prompt "Single-depth WCHAN output"
665 depends on X86
666 ---help---
667 Calculate simpler /proc/<PID>/wchan values. If this option
668 is disabled then wchan values will recurse back to the
669 caller function. This provides more accurate wchan values,
670 at the expense of slightly more scheduling overhead.
671
672 If in doubt, say "Y".
673
674 menuconfig HYPERVISOR_GUEST
675 bool "Linux guest support"
676 ---help---
677 Say Y here to enable options for running Linux under various hyper-
678 visors. This option enables basic hypervisor detection and platform
679 setup.
680
681 If you say N, all options in this submenu will be skipped and
682 disabled, and Linux guest support won't be built in.
683
684 if HYPERVISOR_GUEST
685
686 config PARAVIRT
687 bool "Enable paravirtualization code"
688 ---help---
689 This changes the kernel so it can modify itself when it is run
690 under a hypervisor, potentially improving performance significantly
691 over full virtualization. However, when run without a hypervisor
692 the kernel is theoretically slower and slightly larger.
693
694 config PARAVIRT_DEBUG
695 bool "paravirt-ops debugging"
696 depends on PARAVIRT && DEBUG_KERNEL
697 ---help---
698 Enable to debug paravirt_ops internals. Specifically, BUG if
699 a paravirt_op is missing when it is called.
700
701 config PARAVIRT_SPINLOCKS
702 bool "Paravirtualization layer for spinlocks"
703 depends on PARAVIRT && SMP
704 select UNINLINE_SPIN_UNLOCK if !QUEUED_SPINLOCKS
705 ---help---
706 Paravirtualized spinlocks allow a pvops backend to replace the
707 spinlock implementation with something virtualization-friendly
708 (for example, block the virtual CPU rather than spinning).
709
710 It has a minimal impact on native kernels and gives a nice performance
711 benefit on paravirtualized KVM / Xen kernels.
712
713 If you are unsure how to answer this question, answer Y.
714
715 config QUEUED_LOCK_STAT
716 bool "Paravirt queued spinlock statistics"
717 depends on PARAVIRT_SPINLOCKS && DEBUG_FS && QUEUED_SPINLOCKS
718 ---help---
719 Enable the collection of statistical data on the slowpath
720 behavior of paravirtualized queued spinlocks and report
721 them on debugfs.
722
723 source "arch/x86/xen/Kconfig"
724
725 config KVM_GUEST
726 bool "KVM Guest support (including kvmclock)"
727 depends on PARAVIRT
728 select PARAVIRT_CLOCK
729 default y
730 ---help---
731 This option enables various optimizations for running under the KVM
732 hypervisor. It includes a paravirtualized clock, so that instead
733 of relying on a PIT (or probably other) emulation by the
734 underlying device model, the host provides the guest with
735 timing infrastructure such as time of day, and system time
736
737 config KVM_DEBUG_FS
738 bool "Enable debug information for KVM Guests in debugfs"
739 depends on KVM_GUEST && DEBUG_FS
740 default n
741 ---help---
742 This option enables collection of various statistics for KVM guest.
743 Statistics are displayed in debugfs filesystem. Enabling this option
744 may incur significant overhead.
745
746 source "arch/x86/lguest/Kconfig"
747
748 config PARAVIRT_TIME_ACCOUNTING
749 bool "Paravirtual steal time accounting"
750 depends on PARAVIRT
751 default n
752 ---help---
753 Select this option to enable fine granularity task steal time
754 accounting. Time spent executing other tasks in parallel with
755 the current vCPU is discounted from the vCPU power. To account for
756 that, there can be a small performance impact.
757
758 If in doubt, say N here.
759
760 config PARAVIRT_CLOCK
761 bool
762
763 endif #HYPERVISOR_GUEST
764
765 config NO_BOOTMEM
766 def_bool y
767
768 source "arch/x86/Kconfig.cpu"
769
770 config HPET_TIMER
771 def_bool X86_64
772 prompt "HPET Timer Support" if X86_32
773 ---help---
774 Use the IA-PC HPET (High Precision Event Timer) to manage
775 time in preference to the PIT and RTC, if a HPET is
776 present.
777 HPET is the next generation timer replacing legacy 8254s.
778 The HPET provides a stable time base on SMP
779 systems, unlike the TSC, but it is more expensive to access,
780 as it is off-chip. You can find the HPET spec at
781 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
782
783 You can safely choose Y here. However, HPET will only be
784 activated if the platform and the BIOS support this feature.
785 Otherwise the 8254 will be used for timing services.
786
787 Choose N to continue using the legacy 8254 timer.
788
789 config HPET_EMULATE_RTC
790 def_bool y
791 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
792
793 config APB_TIMER
794 def_bool y if X86_INTEL_MID
795 prompt "Intel MID APB Timer Support" if X86_INTEL_MID
796 select DW_APB_TIMER
797 depends on X86_INTEL_MID && SFI
798 help
799 APB timer is the replacement for 8254, HPET on X86 MID platforms.
800 The APBT provides a stable time base on SMP
801 systems, unlike the TSC, but it is more expensive to access,
802 as it is off-chip. APB timers are always running regardless of CPU
803 C states, they are used as per CPU clockevent device when possible.
804
805 # Mark as expert because too many people got it wrong.
806 # The code disables itself when not needed.
807 config DMI
808 default y
809 select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
810 bool "Enable DMI scanning" if EXPERT
811 ---help---
812 Enabled scanning of DMI to identify machine quirks. Say Y
813 here unless you have verified that your setup is not
814 affected by entries in the DMI blacklist. Required by PNP
815 BIOS code.
816
817 config GART_IOMMU
818 bool "Old AMD GART IOMMU support"
819 select SWIOTLB
820 depends on X86_64 && PCI && AMD_NB
821 ---help---
822 Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
823 GART based hardware IOMMUs.
824
825 The GART supports full DMA access for devices with 32-bit access
826 limitations, on systems with more than 3 GB. This is usually needed
827 for USB, sound, many IDE/SATA chipsets and some other devices.
828
829 Newer systems typically have a modern AMD IOMMU, supported via
830 the CONFIG_AMD_IOMMU=y config option.
831
832 In normal configurations this driver is only active when needed:
833 there's more than 3 GB of memory and the system contains a
834 32-bit limited device.
835
836 If unsure, say Y.
837
838 config CALGARY_IOMMU
839 bool "IBM Calgary IOMMU support"
840 select SWIOTLB
841 depends on X86_64 && PCI
842 ---help---
843 Support for hardware IOMMUs in IBM's xSeries x366 and x460
844 systems. Needed to run systems with more than 3GB of memory
845 properly with 32-bit PCI devices that do not support DAC
846 (Double Address Cycle). Calgary also supports bus level
847 isolation, where all DMAs pass through the IOMMU. This
848 prevents them from going anywhere except their intended
849 destination. This catches hard-to-find kernel bugs and
850 mis-behaving drivers and devices that do not use the DMA-API
851 properly to set up their DMA buffers. The IOMMU can be
852 turned off at boot time with the iommu=off parameter.
853 Normally the kernel will make the right choice by itself.
854 If unsure, say Y.
855
856 config CALGARY_IOMMU_ENABLED_BY_DEFAULT
857 def_bool y
858 prompt "Should Calgary be enabled by default?"
859 depends on CALGARY_IOMMU
860 ---help---
861 Should Calgary be enabled by default? if you choose 'y', Calgary
862 will be used (if it exists). If you choose 'n', Calgary will not be
863 used even if it exists. If you choose 'n' and would like to use
864 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
865 If unsure, say Y.
866
867 # need this always selected by IOMMU for the VIA workaround
868 config SWIOTLB
869 def_bool y if X86_64
870 ---help---
871 Support for software bounce buffers used on x86-64 systems
872 which don't have a hardware IOMMU. Using this PCI devices
873 which can only access 32-bits of memory can be used on systems
874 with more than 3 GB of memory.
875 If unsure, say Y.
876
877 config IOMMU_HELPER
878 def_bool y
879 depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU
880
881 config MAXSMP
882 bool "Enable Maximum number of SMP Processors and NUMA Nodes"
883 depends on X86_64 && SMP && DEBUG_KERNEL
884 select CPUMASK_OFFSTACK
885 ---help---
886 Enable maximum number of CPUS and NUMA Nodes for this architecture.
887 If unsure, say N.
888
889 config NR_CPUS
890 int "Maximum number of CPUs" if SMP && !MAXSMP
891 range 2 8 if SMP && X86_32 && !X86_BIGSMP
892 range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK
893 range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64
894 default "1" if !SMP
895 default "8192" if MAXSMP
896 default "32" if SMP && X86_BIGSMP
897 default "8" if SMP && X86_32
898 default "64" if SMP
899 ---help---
900 This allows you to specify the maximum number of CPUs which this
901 kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum
902 supported value is 8192, otherwise the maximum value is 512. The
903 minimum value which makes sense is 2.
904
905 This is purely to save memory - each supported CPU adds
906 approximately eight kilobytes to the kernel image.
907
908 config SCHED_SMT
909 bool "SMT (Hyperthreading) scheduler support"
910 depends on SMP
911 ---help---
912 SMT scheduler support improves the CPU scheduler's decision making
913 when dealing with Intel Pentium 4 chips with HyperThreading at a
914 cost of slightly increased overhead in some places. If unsure say
915 N here.
916
917 config SCHED_MC
918 def_bool y
919 prompt "Multi-core scheduler support"
920 depends on SMP
921 ---help---
922 Multi-core scheduler support improves the CPU scheduler's decision
923 making when dealing with multi-core CPU chips at a cost of slightly
924 increased overhead in some places. If unsure say N here.
925
926 source "kernel/Kconfig.preempt"
927
928 config UP_LATE_INIT
929 def_bool y
930 depends on !SMP && X86_LOCAL_APIC
931
932 config X86_UP_APIC
933 bool "Local APIC support on uniprocessors" if !PCI_MSI
934 default PCI_MSI
935 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
936 ---help---
937 A local APIC (Advanced Programmable Interrupt Controller) is an
938 integrated interrupt controller in the CPU. If you have a single-CPU
939 system which has a processor with a local APIC, you can say Y here to
940 enable and use it. If you say Y here even though your machine doesn't
941 have a local APIC, then the kernel will still run with no slowdown at
942 all. The local APIC supports CPU-generated self-interrupts (timer,
943 performance counters), and the NMI watchdog which detects hard
944 lockups.
945
946 config X86_UP_IOAPIC
947 bool "IO-APIC support on uniprocessors"
948 depends on X86_UP_APIC
949 ---help---
950 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
951 SMP-capable replacement for PC-style interrupt controllers. Most
952 SMP systems and many recent uniprocessor systems have one.
953
954 If you have a single-CPU system with an IO-APIC, you can say Y here
955 to use it. If you say Y here even though your machine doesn't have
956 an IO-APIC, then the kernel will still run with no slowdown at all.
957
958 config X86_LOCAL_APIC
959 def_bool y
960 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
961 select IRQ_DOMAIN_HIERARCHY
962 select PCI_MSI_IRQ_DOMAIN if PCI_MSI
963
964 config X86_IO_APIC
965 def_bool y
966 depends on X86_LOCAL_APIC || X86_UP_IOAPIC
967
968 config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
969 bool "Reroute for broken boot IRQs"
970 depends on X86_IO_APIC
971 ---help---
972 This option enables a workaround that fixes a source of
973 spurious interrupts. This is recommended when threaded
974 interrupt handling is used on systems where the generation of
975 superfluous "boot interrupts" cannot be disabled.
976
977 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
978 entry in the chipset's IO-APIC is masked (as, e.g. the RT
979 kernel does during interrupt handling). On chipsets where this
980 boot IRQ generation cannot be disabled, this workaround keeps
981 the original IRQ line masked so that only the equivalent "boot
982 IRQ" is delivered to the CPUs. The workaround also tells the
983 kernel to set up the IRQ handler on the boot IRQ line. In this
984 way only one interrupt is delivered to the kernel. Otherwise
985 the spurious second interrupt may cause the kernel to bring
986 down (vital) interrupt lines.
987
988 Only affects "broken" chipsets. Interrupt sharing may be
989 increased on these systems.
990
991 config X86_MCE
992 bool "Machine Check / overheating reporting"
993 select GENERIC_ALLOCATOR
994 default y
995 ---help---
996 Machine Check support allows the processor to notify the
997 kernel if it detects a problem (e.g. overheating, data corruption).
998 The action the kernel takes depends on the severity of the problem,
999 ranging from warning messages to halting the machine.
1000
1001 config X86_MCE_INTEL
1002 def_bool y
1003 prompt "Intel MCE features"
1004 depends on X86_MCE && X86_LOCAL_APIC
1005 ---help---
1006 Additional support for intel specific MCE features such as
1007 the thermal monitor.
1008
1009 config X86_MCE_AMD
1010 def_bool y
1011 prompt "AMD MCE features"
1012 depends on X86_MCE && X86_LOCAL_APIC
1013 ---help---
1014 Additional support for AMD specific MCE features such as
1015 the DRAM Error Threshold.
1016
1017 config X86_ANCIENT_MCE
1018 bool "Support for old Pentium 5 / WinChip machine checks"
1019 depends on X86_32 && X86_MCE
1020 ---help---
1021 Include support for machine check handling on old Pentium 5 or WinChip
1022 systems. These typically need to be enabled explicitly on the command
1023 line.
1024
1025 config X86_MCE_THRESHOLD
1026 depends on X86_MCE_AMD || X86_MCE_INTEL
1027 def_bool y
1028
1029 config X86_MCE_INJECT
1030 depends on X86_MCE
1031 tristate "Machine check injector support"
1032 ---help---
1033 Provide support for injecting machine checks for testing purposes.
1034 If you don't know what a machine check is and you don't do kernel
1035 QA it is safe to say n.
1036
1037 config X86_THERMAL_VECTOR
1038 def_bool y
1039 depends on X86_MCE_INTEL
1040
1041 config X86_LEGACY_VM86
1042 bool "Legacy VM86 support"
1043 default n
1044 depends on X86_32
1045 ---help---
1046 This option allows user programs to put the CPU into V8086
1047 mode, which is an 80286-era approximation of 16-bit real mode.
1048
1049 Some very old versions of X and/or vbetool require this option
1050 for user mode setting. Similarly, DOSEMU will use it if
1051 available to accelerate real mode DOS programs. However, any
1052 recent version of DOSEMU, X, or vbetool should be fully
1053 functional even without kernel VM86 support, as they will all
1054 fall back to software emulation. Nevertheless, if you are using
1055 a 16-bit DOS program where 16-bit performance matters, vm86
1056 mode might be faster than emulation and you might want to
1057 enable this option.
1058
1059 Note that any app that works on a 64-bit kernel is unlikely to
1060 need this option, as 64-bit kernels don't, and can't, support
1061 V8086 mode. This option is also unrelated to 16-bit protected
1062 mode and is not needed to run most 16-bit programs under Wine.
1063
1064 Enabling this option increases the complexity of the kernel
1065 and slows down exception handling a tiny bit.
1066
1067 If unsure, say N here.
1068
1069 config VM86
1070 bool
1071 default X86_LEGACY_VM86
1072
1073 config X86_16BIT
1074 bool "Enable support for 16-bit segments" if EXPERT
1075 default y
1076 depends on MODIFY_LDT_SYSCALL
1077 ---help---
1078 This option is required by programs like Wine to run 16-bit
1079 protected mode legacy code on x86 processors. Disabling
1080 this option saves about 300 bytes on i386, or around 6K text
1081 plus 16K runtime memory on x86-64,
1082
1083 config X86_ESPFIX32
1084 def_bool y
1085 depends on X86_16BIT && X86_32
1086
1087 config X86_ESPFIX64
1088 def_bool y
1089 depends on X86_16BIT && X86_64
1090
1091 config X86_VSYSCALL_EMULATION
1092 bool "Enable vsyscall emulation" if EXPERT
1093 default y
1094 depends on X86_64
1095 ---help---
1096 This enables emulation of the legacy vsyscall page. Disabling
1097 it is roughly equivalent to booting with vsyscall=none, except
1098 that it will also disable the helpful warning if a program
1099 tries to use a vsyscall. With this option set to N, offending
1100 programs will just segfault, citing addresses of the form
1101 0xffffffffff600?00.
1102
1103 This option is required by many programs built before 2013, and
1104 care should be used even with newer programs if set to N.
1105
1106 Disabling this option saves about 7K of kernel size and
1107 possibly 4K of additional runtime pagetable memory.
1108
1109 config TOSHIBA
1110 tristate "Toshiba Laptop support"
1111 depends on X86_32
1112 ---help---
1113 This adds a driver to safely access the System Management Mode of
1114 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
1115 not work on models with a Phoenix BIOS. The System Management Mode
1116 is used to set the BIOS and power saving options on Toshiba portables.
1117
1118 For information on utilities to make use of this driver see the
1119 Toshiba Linux utilities web site at:
1120 <http://www.buzzard.org.uk/toshiba/>.
1121
1122 Say Y if you intend to run this kernel on a Toshiba portable.
1123 Say N otherwise.
1124
1125 config I8K
1126 tristate "Dell i8k legacy laptop support"
1127 select HWMON
1128 select SENSORS_DELL_SMM
1129 ---help---
1130 This option enables legacy /proc/i8k userspace interface in hwmon
1131 dell-smm-hwmon driver. Character file /proc/i8k reports bios version,
1132 temperature and allows controlling fan speeds of Dell laptops via
1133 System Management Mode. For old Dell laptops (like Dell Inspiron 8000)
1134 it reports also power and hotkey status. For fan speed control is
1135 needed userspace package i8kutils.
1136
1137 Say Y if you intend to run this kernel on old Dell laptops or want to
1138 use userspace package i8kutils.
1139 Say N otherwise.
1140
1141 config X86_REBOOTFIXUPS
1142 bool "Enable X86 board specific fixups for reboot"
1143 depends on X86_32
1144 ---help---
1145 This enables chipset and/or board specific fixups to be done
1146 in order to get reboot to work correctly. This is only needed on
1147 some combinations of hardware and BIOS. The symptom, for which
1148 this config is intended, is when reboot ends with a stalled/hung
1149 system.
1150
1151 Currently, the only fixup is for the Geode machines using
1152 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
1153
1154 Say Y if you want to enable the fixup. Currently, it's safe to
1155 enable this option even if you don't need it.
1156 Say N otherwise.
1157
1158 config MICROCODE
1159 bool "CPU microcode loading support"
1160 default y
1161 depends on CPU_SUP_AMD || CPU_SUP_INTEL
1162 depends on BLK_DEV_INITRD
1163 select FW_LOADER
1164 ---help---
1165
1166 If you say Y here, you will be able to update the microcode on
1167 certain Intel and AMD processors. The Intel support is for the
1168 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4,
1169 Xeon etc. The AMD support is for families 0x10 and later. You will
1170 obviously need the actual microcode binary data itself which is not
1171 shipped with the Linux kernel.
1172
1173 This option selects the general module only, you need to select
1174 at least one vendor specific module as well.
1175
1176 To compile this driver as a module, choose M here: the module
1177 will be called microcode.
1178
1179 config MICROCODE_INTEL
1180 bool "Intel microcode loading support"
1181 depends on MICROCODE
1182 default MICROCODE
1183 select FW_LOADER
1184 ---help---
1185 This options enables microcode patch loading support for Intel
1186 processors.
1187
1188 For the current Intel microcode data package go to
1189 <https://downloadcenter.intel.com> and search for
1190 'Linux Processor Microcode Data File'.
1191
1192 config MICROCODE_AMD
1193 bool "AMD microcode loading support"
1194 depends on MICROCODE
1195 select FW_LOADER
1196 ---help---
1197 If you select this option, microcode patch loading support for AMD
1198 processors will be enabled.
1199
1200 config MICROCODE_OLD_INTERFACE
1201 def_bool y
1202 depends on MICROCODE
1203
1204 config X86_MSR
1205 tristate "/dev/cpu/*/msr - Model-specific register support"
1206 ---help---
1207 This device gives privileged processes access to the x86
1208 Model-Specific Registers (MSRs). It is a character device with
1209 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1210 MSR accesses are directed to a specific CPU on multi-processor
1211 systems.
1212
1213 config X86_CPUID
1214 tristate "/dev/cpu/*/cpuid - CPU information support"
1215 ---help---
1216 This device gives processes access to the x86 CPUID instruction to
1217 be executed on a specific processor. It is a character device
1218 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1219 /dev/cpu/31/cpuid.
1220
1221 choice
1222 prompt "High Memory Support"
1223 default HIGHMEM4G
1224 depends on X86_32
1225
1226 config NOHIGHMEM
1227 bool "off"
1228 ---help---
1229 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1230 However, the address space of 32-bit x86 processors is only 4
1231 Gigabytes large. That means that, if you have a large amount of
1232 physical memory, not all of it can be "permanently mapped" by the
1233 kernel. The physical memory that's not permanently mapped is called
1234 "high memory".
1235
1236 If you are compiling a kernel which will never run on a machine with
1237 more than 1 Gigabyte total physical RAM, answer "off" here (default
1238 choice and suitable for most users). This will result in a "3GB/1GB"
1239 split: 3GB are mapped so that each process sees a 3GB virtual memory
1240 space and the remaining part of the 4GB virtual memory space is used
1241 by the kernel to permanently map as much physical memory as
1242 possible.
1243
1244 If the machine has between 1 and 4 Gigabytes physical RAM, then
1245 answer "4GB" here.
1246
1247 If more than 4 Gigabytes is used then answer "64GB" here. This
1248 selection turns Intel PAE (Physical Address Extension) mode on.
1249 PAE implements 3-level paging on IA32 processors. PAE is fully
1250 supported by Linux, PAE mode is implemented on all recent Intel
1251 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1252 then the kernel will not boot on CPUs that don't support PAE!
1253
1254 The actual amount of total physical memory will either be
1255 auto detected or can be forced by using a kernel command line option
1256 such as "mem=256M". (Try "man bootparam" or see the documentation of
1257 your boot loader (lilo or loadlin) about how to pass options to the
1258 kernel at boot time.)
1259
1260 If unsure, say "off".
1261
1262 config HIGHMEM4G
1263 bool "4GB"
1264 ---help---
1265 Select this if you have a 32-bit processor and between 1 and 4
1266 gigabytes of physical RAM.
1267
1268 config HIGHMEM64G
1269 bool "64GB"
1270 depends on !M486
1271 select X86_PAE
1272 ---help---
1273 Select this if you have a 32-bit processor and more than 4
1274 gigabytes of physical RAM.
1275
1276 endchoice
1277
1278 choice
1279 prompt "Memory split" if EXPERT
1280 default VMSPLIT_3G
1281 depends on X86_32
1282 ---help---
1283 Select the desired split between kernel and user memory.
1284
1285 If the address range available to the kernel is less than the
1286 physical memory installed, the remaining memory will be available
1287 as "high memory". Accessing high memory is a little more costly
1288 than low memory, as it needs to be mapped into the kernel first.
1289 Note that increasing the kernel address space limits the range
1290 available to user programs, making the address space there
1291 tighter. Selecting anything other than the default 3G/1G split
1292 will also likely make your kernel incompatible with binary-only
1293 kernel modules.
1294
1295 If you are not absolutely sure what you are doing, leave this
1296 option alone!
1297
1298 config VMSPLIT_3G
1299 bool "3G/1G user/kernel split"
1300 config VMSPLIT_3G_OPT
1301 depends on !X86_PAE
1302 bool "3G/1G user/kernel split (for full 1G low memory)"
1303 config VMSPLIT_2G
1304 bool "2G/2G user/kernel split"
1305 config VMSPLIT_2G_OPT
1306 depends on !X86_PAE
1307 bool "2G/2G user/kernel split (for full 2G low memory)"
1308 config VMSPLIT_1G
1309 bool "1G/3G user/kernel split"
1310 endchoice
1311
1312 config PAGE_OFFSET
1313 hex
1314 default 0xB0000000 if VMSPLIT_3G_OPT
1315 default 0x80000000 if VMSPLIT_2G
1316 default 0x78000000 if VMSPLIT_2G_OPT
1317 default 0x40000000 if VMSPLIT_1G
1318 default 0xC0000000
1319 depends on X86_32
1320
1321 config HIGHMEM
1322 def_bool y
1323 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
1324
1325 config X86_PAE
1326 bool "PAE (Physical Address Extension) Support"
1327 depends on X86_32 && !HIGHMEM4G
1328 select SWIOTLB
1329 ---help---
1330 PAE is required for NX support, and furthermore enables
1331 larger swapspace support for non-overcommit purposes. It
1332 has the cost of more pagetable lookup overhead, and also
1333 consumes more pagetable space per process.
1334
1335 config ARCH_PHYS_ADDR_T_64BIT
1336 def_bool y
1337 depends on X86_64 || X86_PAE
1338
1339 config ARCH_DMA_ADDR_T_64BIT
1340 def_bool y
1341 depends on X86_64 || HIGHMEM64G
1342
1343 config X86_DIRECT_GBPAGES
1344 def_bool y
1345 depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK
1346 ---help---
1347 Certain kernel features effectively disable kernel
1348 linear 1 GB mappings (even if the CPU otherwise
1349 supports them), so don't confuse the user by printing
1350 that we have them enabled.
1351
1352 # Common NUMA Features
1353 config NUMA
1354 bool "Numa Memory Allocation and Scheduler Support"
1355 depends on SMP
1356 depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
1357 default y if X86_BIGSMP
1358 ---help---
1359 Enable NUMA (Non Uniform Memory Access) support.
1360
1361 The kernel will try to allocate memory used by a CPU on the
1362 local memory controller of the CPU and add some more
1363 NUMA awareness to the kernel.
1364
1365 For 64-bit this is recommended if the system is Intel Core i7
1366 (or later), AMD Opteron, or EM64T NUMA.
1367
1368 For 32-bit this is only needed if you boot a 32-bit
1369 kernel on a 64-bit NUMA platform.
1370
1371 Otherwise, you should say N.
1372
1373 config AMD_NUMA
1374 def_bool y
1375 prompt "Old style AMD Opteron NUMA detection"
1376 depends on X86_64 && NUMA && PCI
1377 ---help---
1378 Enable AMD NUMA node topology detection. You should say Y here if
1379 you have a multi processor AMD system. This uses an old method to
1380 read the NUMA configuration directly from the builtin Northbridge
1381 of Opteron. It is recommended to use X86_64_ACPI_NUMA instead,
1382 which also takes priority if both are compiled in.
1383
1384 config X86_64_ACPI_NUMA
1385 def_bool y
1386 prompt "ACPI NUMA detection"
1387 depends on X86_64 && NUMA && ACPI && PCI
1388 select ACPI_NUMA
1389 ---help---
1390 Enable ACPI SRAT based node topology detection.
1391
1392 # Some NUMA nodes have memory ranges that span
1393 # other nodes. Even though a pfn is valid and
1394 # between a node's start and end pfns, it may not
1395 # reside on that node. See memmap_init_zone()
1396 # for details.
1397 config NODES_SPAN_OTHER_NODES
1398 def_bool y
1399 depends on X86_64_ACPI_NUMA
1400
1401 config NUMA_EMU
1402 bool "NUMA emulation"
1403 depends on NUMA
1404 ---help---
1405 Enable NUMA emulation. A flat machine will be split
1406 into virtual nodes when booted with "numa=fake=N", where N is the
1407 number of nodes. This is only useful for debugging.
1408
1409 config NODES_SHIFT
1410 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
1411 range 1 10
1412 default "10" if MAXSMP
1413 default "6" if X86_64
1414 default "3"
1415 depends on NEED_MULTIPLE_NODES
1416 ---help---
1417 Specify the maximum number of NUMA Nodes available on the target
1418 system. Increases memory reserved to accommodate various tables.
1419
1420 config ARCH_HAVE_MEMORY_PRESENT
1421 def_bool y
1422 depends on X86_32 && DISCONTIGMEM
1423
1424 config NEED_NODE_MEMMAP_SIZE
1425 def_bool y
1426 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
1427
1428 config ARCH_FLATMEM_ENABLE
1429 def_bool y
1430 depends on X86_32 && !NUMA
1431
1432 config ARCH_DISCONTIGMEM_ENABLE
1433 def_bool y
1434 depends on NUMA && X86_32
1435
1436 config ARCH_DISCONTIGMEM_DEFAULT
1437 def_bool y
1438 depends on NUMA && X86_32
1439
1440 config ARCH_SPARSEMEM_ENABLE
1441 def_bool y
1442 depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD
1443 select SPARSEMEM_STATIC if X86_32
1444 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1445
1446 config ARCH_SPARSEMEM_DEFAULT
1447 def_bool y
1448 depends on X86_64
1449
1450 config ARCH_SELECT_MEMORY_MODEL
1451 def_bool y
1452 depends on ARCH_SPARSEMEM_ENABLE
1453
1454 config ARCH_MEMORY_PROBE
1455 bool "Enable sysfs memory/probe interface"
1456 depends on X86_64 && MEMORY_HOTPLUG
1457 help
1458 This option enables a sysfs memory/probe interface for testing.
1459 See Documentation/memory-hotplug.txt for more information.
1460 If you are unsure how to answer this question, answer N.
1461
1462 config ARCH_PROC_KCORE_TEXT
1463 def_bool y
1464 depends on X86_64 && PROC_KCORE
1465
1466 config ILLEGAL_POINTER_VALUE
1467 hex
1468 default 0 if X86_32
1469 default 0xdead000000000000 if X86_64
1470
1471 source "mm/Kconfig"
1472
1473 config X86_PMEM_LEGACY_DEVICE
1474 bool
1475
1476 config X86_PMEM_LEGACY
1477 tristate "Support non-standard NVDIMMs and ADR protected memory"
1478 depends on PHYS_ADDR_T_64BIT
1479 depends on BLK_DEV
1480 select X86_PMEM_LEGACY_DEVICE
1481 select LIBNVDIMM
1482 help
1483 Treat memory marked using the non-standard e820 type of 12 as used
1484 by the Intel Sandy Bridge-EP reference BIOS as protected memory.
1485 The kernel will offer these regions to the 'pmem' driver so
1486 they can be used for persistent storage.
1487
1488 Say Y if unsure.
1489
1490 config HIGHPTE
1491 bool "Allocate 3rd-level pagetables from highmem"
1492 depends on HIGHMEM
1493 ---help---
1494 The VM uses one page table entry for each page of physical memory.
1495 For systems with a lot of RAM, this can be wasteful of precious
1496 low memory. Setting this option will put user-space page table
1497 entries in high memory.
1498
1499 config X86_CHECK_BIOS_CORRUPTION
1500 bool "Check for low memory corruption"
1501 ---help---
1502 Periodically check for memory corruption in low memory, which
1503 is suspected to be caused by BIOS. Even when enabled in the
1504 configuration, it is disabled at runtime. Enable it by
1505 setting "memory_corruption_check=1" on the kernel command
1506 line. By default it scans the low 64k of memory every 60
1507 seconds; see the memory_corruption_check_size and
1508 memory_corruption_check_period parameters in
1509 Documentation/kernel-parameters.txt to adjust this.
1510
1511 When enabled with the default parameters, this option has
1512 almost no overhead, as it reserves a relatively small amount
1513 of memory and scans it infrequently. It both detects corruption
1514 and prevents it from affecting the running system.
1515
1516 It is, however, intended as a diagnostic tool; if repeatable
1517 BIOS-originated corruption always affects the same memory,
1518 you can use memmap= to prevent the kernel from using that
1519 memory.
1520
1521 config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
1522 bool "Set the default setting of memory_corruption_check"
1523 depends on X86_CHECK_BIOS_CORRUPTION
1524 default y
1525 ---help---
1526 Set whether the default state of memory_corruption_check is
1527 on or off.
1528
1529 config X86_RESERVE_LOW
1530 int "Amount of low memory, in kilobytes, to reserve for the BIOS"
1531 default 64
1532 range 4 640
1533 ---help---
1534 Specify the amount of low memory to reserve for the BIOS.
1535
1536 The first page contains BIOS data structures that the kernel
1537 must not use, so that page must always be reserved.
1538
1539 By default we reserve the first 64K of physical RAM, as a
1540 number of BIOSes are known to corrupt that memory range
1541 during events such as suspend/resume or monitor cable
1542 insertion, so it must not be used by the kernel.
1543
1544 You can set this to 4 if you are absolutely sure that you
1545 trust the BIOS to get all its memory reservations and usages
1546 right. If you know your BIOS have problems beyond the
1547 default 64K area, you can set this to 640 to avoid using the
1548 entire low memory range.
1549
1550 If you have doubts about the BIOS (e.g. suspend/resume does
1551 not work or there's kernel crashes after certain hardware
1552 hotplug events) then you might want to enable
1553 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check
1554 typical corruption patterns.
1555
1556 Leave this to the default value of 64 if you are unsure.
1557
1558 config MATH_EMULATION
1559 bool
1560 depends on MODIFY_LDT_SYSCALL
1561 prompt "Math emulation" if X86_32
1562 ---help---
1563 Linux can emulate a math coprocessor (used for floating point
1564 operations) if you don't have one. 486DX and Pentium processors have
1565 a math coprocessor built in, 486SX and 386 do not, unless you added
1566 a 487DX or 387, respectively. (The messages during boot time can
1567 give you some hints here ["man dmesg"].) Everyone needs either a
1568 coprocessor or this emulation.
1569
1570 If you don't have a math coprocessor, you need to say Y here; if you
1571 say Y here even though you have a coprocessor, the coprocessor will
1572 be used nevertheless. (This behavior can be changed with the kernel
1573 command line option "no387", which comes handy if your coprocessor
1574 is broken. Try "man bootparam" or see the documentation of your boot
1575 loader (lilo or loadlin) about how to pass options to the kernel at
1576 boot time.) This means that it is a good idea to say Y here if you
1577 intend to use this kernel on different machines.
1578
1579 More information about the internals of the Linux math coprocessor
1580 emulation can be found in <file:arch/x86/math-emu/README>.
1581
1582 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1583 kernel, it won't hurt.
1584
1585 config MTRR
1586 def_bool y
1587 prompt "MTRR (Memory Type Range Register) support" if EXPERT
1588 ---help---
1589 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1590 the Memory Type Range Registers (MTRRs) may be used to control
1591 processor access to memory ranges. This is most useful if you have
1592 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1593 allows bus write transfers to be combined into a larger transfer
1594 before bursting over the PCI/AGP bus. This can increase performance
1595 of image write operations 2.5 times or more. Saying Y here creates a
1596 /proc/mtrr file which may be used to manipulate your processor's
1597 MTRRs. Typically the X server should use this.
1598
1599 This code has a reasonably generic interface so that similar
1600 control registers on other processors can be easily supported
1601 as well:
1602
1603 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1604 Registers (ARRs) which provide a similar functionality to MTRRs. For
1605 these, the ARRs are used to emulate the MTRRs.
1606 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1607 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1608 write-combining. All of these processors are supported by this code
1609 and it makes sense to say Y here if you have one of them.
1610
1611 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1612 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1613 can lead to all sorts of problems, so it's good to say Y here.
1614
1615 You can safely say Y even if your machine doesn't have MTRRs, you'll
1616 just add about 9 KB to your kernel.
1617
1618 See <file:Documentation/x86/mtrr.txt> for more information.
1619
1620 config MTRR_SANITIZER
1621 def_bool y
1622 prompt "MTRR cleanup support"
1623 depends on MTRR
1624 ---help---
1625 Convert MTRR layout from continuous to discrete, so X drivers can
1626 add writeback entries.
1627
1628 Can be disabled with disable_mtrr_cleanup on the kernel command line.
1629 The largest mtrr entry size for a continuous block can be set with
1630 mtrr_chunk_size.
1631
1632 If unsure, say Y.
1633
1634 config MTRR_SANITIZER_ENABLE_DEFAULT
1635 int "MTRR cleanup enable value (0-1)"
1636 range 0 1
1637 default "0"
1638 depends on MTRR_SANITIZER
1639 ---help---
1640 Enable mtrr cleanup default value
1641
1642 config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1643 int "MTRR cleanup spare reg num (0-7)"
1644 range 0 7
1645 default "1"
1646 depends on MTRR_SANITIZER
1647 ---help---
1648 mtrr cleanup spare entries default, it can be changed via
1649 mtrr_spare_reg_nr=N on the kernel command line.
1650
1651 config X86_PAT
1652 def_bool y
1653 prompt "x86 PAT support" if EXPERT
1654 depends on MTRR
1655 ---help---
1656 Use PAT attributes to setup page level cache control.
1657
1658 PATs are the modern equivalents of MTRRs and are much more
1659 flexible than MTRRs.
1660
1661 Say N here if you see bootup problems (boot crash, boot hang,
1662 spontaneous reboots) or a non-working video driver.
1663
1664 If unsure, say Y.
1665
1666 config ARCH_USES_PG_UNCACHED
1667 def_bool y
1668 depends on X86_PAT
1669
1670 config ARCH_RANDOM
1671 def_bool y
1672 prompt "x86 architectural random number generator" if EXPERT
1673 ---help---
1674 Enable the x86 architectural RDRAND instruction
1675 (Intel Bull Mountain technology) to generate random numbers.
1676 If supported, this is a high bandwidth, cryptographically
1677 secure hardware random number generator.
1678
1679 config X86_SMAP
1680 def_bool y
1681 prompt "Supervisor Mode Access Prevention" if EXPERT
1682 ---help---
1683 Supervisor Mode Access Prevention (SMAP) is a security
1684 feature in newer Intel processors. There is a small
1685 performance cost if this enabled and turned on; there is
1686 also a small increase in the kernel size if this is enabled.
1687
1688 If unsure, say Y.
1689
1690 config X86_INTEL_MPX
1691 prompt "Intel MPX (Memory Protection Extensions)"
1692 def_bool n
1693 depends on CPU_SUP_INTEL
1694 ---help---
1695 MPX provides hardware features that can be used in
1696 conjunction with compiler-instrumented code to check
1697 memory references. It is designed to detect buffer
1698 overflow or underflow bugs.
1699
1700 This option enables running applications which are
1701 instrumented or otherwise use MPX. It does not use MPX
1702 itself inside the kernel or to protect the kernel
1703 against bad memory references.
1704
1705 Enabling this option will make the kernel larger:
1706 ~8k of kernel text and 36 bytes of data on a 64-bit
1707 defconfig. It adds a long to the 'mm_struct' which
1708 will increase the kernel memory overhead of each
1709 process and adds some branches to paths used during
1710 exec() and munmap().
1711
1712 For details, see Documentation/x86/intel_mpx.txt
1713
1714 If unsure, say N.
1715
1716 config EFI
1717 bool "EFI runtime service support"
1718 depends on ACPI
1719 select UCS2_STRING
1720 select EFI_RUNTIME_WRAPPERS
1721 ---help---
1722 This enables the kernel to use EFI runtime services that are
1723 available (such as the EFI variable services).
1724
1725 This option is only useful on systems that have EFI firmware.
1726 In addition, you should use the latest ELILO loader available
1727 at <http://elilo.sourceforge.net> in order to take advantage
1728 of EFI runtime services. However, even with this option, the
1729 resultant kernel should continue to boot on existing non-EFI
1730 platforms.
1731
1732 config EFI_STUB
1733 bool "EFI stub support"
1734 depends on EFI && !X86_USE_3DNOW
1735 select RELOCATABLE
1736 ---help---
1737 This kernel feature allows a bzImage to be loaded directly
1738 by EFI firmware without the use of a bootloader.
1739
1740 See Documentation/efi-stub.txt for more information.
1741
1742 config EFI_MIXED
1743 bool "EFI mixed-mode support"
1744 depends on EFI_STUB && X86_64
1745 ---help---
1746 Enabling this feature allows a 64-bit kernel to be booted
1747 on a 32-bit firmware, provided that your CPU supports 64-bit
1748 mode.
1749
1750 Note that it is not possible to boot a mixed-mode enabled
1751 kernel via the EFI boot stub - a bootloader that supports
1752 the EFI handover protocol must be used.
1753
1754 If unsure, say N.
1755
1756 config SECCOMP
1757 def_bool y
1758 prompt "Enable seccomp to safely compute untrusted bytecode"
1759 ---help---
1760 This kernel feature is useful for number crunching applications
1761 that may need to compute untrusted bytecode during their
1762 execution. By using pipes or other transports made available to
1763 the process as file descriptors supporting the read/write
1764 syscalls, it's possible to isolate those applications in
1765 their own address space using seccomp. Once seccomp is
1766 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1767 and the task is only allowed to execute a few safe syscalls
1768 defined by each seccomp mode.
1769
1770 If unsure, say Y. Only embedded should say N here.
1771
1772 source kernel/Kconfig.hz
1773
1774 config KEXEC
1775 bool "kexec system call"
1776 select KEXEC_CORE
1777 ---help---
1778 kexec is a system call that implements the ability to shutdown your
1779 current kernel, and to start another kernel. It is like a reboot
1780 but it is independent of the system firmware. And like a reboot
1781 you can start any kernel with it, not just Linux.
1782
1783 The name comes from the similarity to the exec system call.
1784
1785 It is an ongoing process to be certain the hardware in a machine
1786 is properly shutdown, so do not be surprised if this code does not
1787 initially work for you. As of this writing the exact hardware
1788 interface is strongly in flux, so no good recommendation can be
1789 made.
1790
1791 config KEXEC_FILE
1792 bool "kexec file based system call"
1793 select KEXEC_CORE
1794 select BUILD_BIN2C
1795 depends on X86_64
1796 depends on CRYPTO=y
1797 depends on CRYPTO_SHA256=y
1798 ---help---
1799 This is new version of kexec system call. This system call is
1800 file based and takes file descriptors as system call argument
1801 for kernel and initramfs as opposed to list of segments as
1802 accepted by previous system call.
1803
1804 config KEXEC_VERIFY_SIG
1805 bool "Verify kernel signature during kexec_file_load() syscall"
1806 depends on KEXEC_FILE
1807 ---help---
1808 This option makes kernel signature verification mandatory for
1809 the kexec_file_load() syscall.
1810
1811 In addition to that option, you need to enable signature
1812 verification for the corresponding kernel image type being
1813 loaded in order for this to work.
1814
1815 config KEXEC_BZIMAGE_VERIFY_SIG
1816 bool "Enable bzImage signature verification support"
1817 depends on KEXEC_VERIFY_SIG
1818 depends on SIGNED_PE_FILE_VERIFICATION
1819 select SYSTEM_TRUSTED_KEYRING
1820 ---help---
1821 Enable bzImage signature verification support.
1822
1823 config CRASH_DUMP
1824 bool "kernel crash dumps"
1825 depends on X86_64 || (X86_32 && HIGHMEM)
1826 ---help---
1827 Generate crash dump after being started by kexec.
1828 This should be normally only set in special crash dump kernels
1829 which are loaded in the main kernel with kexec-tools into
1830 a specially reserved region and then later executed after
1831 a crash by kdump/kexec. The crash dump kernel must be compiled
1832 to a memory address not used by the main kernel or BIOS using
1833 PHYSICAL_START, or it must be built as a relocatable image
1834 (CONFIG_RELOCATABLE=y).
1835 For more details see Documentation/kdump/kdump.txt
1836
1837 config KEXEC_JUMP
1838 bool "kexec jump"
1839 depends on KEXEC && HIBERNATION
1840 ---help---
1841 Jump between original kernel and kexeced kernel and invoke
1842 code in physical address mode via KEXEC
1843
1844 config PHYSICAL_START
1845 hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
1846 default "0x1000000"
1847 ---help---
1848 This gives the physical address where the kernel is loaded.
1849
1850 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1851 bzImage will decompress itself to above physical address and
1852 run from there. Otherwise, bzImage will run from the address where
1853 it has been loaded by the boot loader and will ignore above physical
1854 address.
1855
1856 In normal kdump cases one does not have to set/change this option
1857 as now bzImage can be compiled as a completely relocatable image
1858 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1859 address. This option is mainly useful for the folks who don't want
1860 to use a bzImage for capturing the crash dump and want to use a
1861 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1862 to be specifically compiled to run from a specific memory area
1863 (normally a reserved region) and this option comes handy.
1864
1865 So if you are using bzImage for capturing the crash dump,
1866 leave the value here unchanged to 0x1000000 and set
1867 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1868 for capturing the crash dump change this value to start of
1869 the reserved region. In other words, it can be set based on
1870 the "X" value as specified in the "crashkernel=YM@XM"
1871 command line boot parameter passed to the panic-ed
1872 kernel. Please take a look at Documentation/kdump/kdump.txt
1873 for more details about crash dumps.
1874
1875 Usage of bzImage for capturing the crash dump is recommended as
1876 one does not have to build two kernels. Same kernel can be used
1877 as production kernel and capture kernel. Above option should have
1878 gone away after relocatable bzImage support is introduced. But it
1879 is present because there are users out there who continue to use
1880 vmlinux for dump capture. This option should go away down the
1881 line.
1882
1883 Don't change this unless you know what you are doing.
1884
1885 config RELOCATABLE
1886 bool "Build a relocatable kernel"
1887 default y
1888 ---help---
1889 This builds a kernel image that retains relocation information
1890 so it can be loaded someplace besides the default 1MB.
1891 The relocations tend to make the kernel binary about 10% larger,
1892 but are discarded at runtime.
1893
1894 One use is for the kexec on panic case where the recovery kernel
1895 must live at a different physical address than the primary
1896 kernel.
1897
1898 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1899 it has been loaded at and the compile time physical address
1900 (CONFIG_PHYSICAL_START) is used as the minimum location.
1901
1902 config RANDOMIZE_BASE
1903 bool "Randomize the address of the kernel image"
1904 depends on RELOCATABLE
1905 default n
1906 ---help---
1907 Randomizes the physical and virtual address at which the
1908 kernel image is decompressed, as a security feature that
1909 deters exploit attempts relying on knowledge of the location
1910 of kernel internals.
1911
1912 Entropy is generated using the RDRAND instruction if it is
1913 supported. If RDTSC is supported, it is used as well. If
1914 neither RDRAND nor RDTSC are supported, then randomness is
1915 read from the i8254 timer.
1916
1917 The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET,
1918 and aligned according to PHYSICAL_ALIGN. Since the kernel is
1919 built using 2GiB addressing, and PHYSICAL_ALGIN must be at a
1920 minimum of 2MiB, only 10 bits of entropy is theoretically
1921 possible. At best, due to page table layouts, 64-bit can use
1922 9 bits of entropy and 32-bit uses 8 bits.
1923
1924 If unsure, say N.
1925
1926 config RANDOMIZE_BASE_MAX_OFFSET
1927 hex "Maximum kASLR offset allowed" if EXPERT
1928 depends on RANDOMIZE_BASE
1929 range 0x0 0x20000000 if X86_32
1930 default "0x20000000" if X86_32
1931 range 0x0 0x40000000 if X86_64
1932 default "0x40000000" if X86_64
1933 ---help---
1934 The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical
1935 memory is used to determine the maximal offset in bytes that will
1936 be applied to the kernel when kernel Address Space Layout
1937 Randomization (kASLR) is active. This must be a multiple of
1938 PHYSICAL_ALIGN.
1939
1940 On 32-bit this is limited to 512MiB by page table layouts. The
1941 default is 512MiB.
1942
1943 On 64-bit this is limited by how the kernel fixmap page table is
1944 positioned, so this cannot be larger than 1GiB currently. Without
1945 RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel
1946 and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the
1947 modules area will shrink to compensate, up to the current maximum
1948 1GiB to 1GiB split. The default is 1GiB.
1949
1950 If unsure, leave at the default value.
1951
1952 # Relocation on x86 needs some additional build support
1953 config X86_NEED_RELOCS
1954 def_bool y
1955 depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
1956
1957 config PHYSICAL_ALIGN
1958 hex "Alignment value to which kernel should be aligned"
1959 default "0x200000"
1960 range 0x2000 0x1000000 if X86_32
1961 range 0x200000 0x1000000 if X86_64
1962 ---help---
1963 This value puts the alignment restrictions on physical address
1964 where kernel is loaded and run from. Kernel is compiled for an
1965 address which meets above alignment restriction.
1966
1967 If bootloader loads the kernel at a non-aligned address and
1968 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1969 address aligned to above value and run from there.
1970
1971 If bootloader loads the kernel at a non-aligned address and
1972 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1973 load address and decompress itself to the address it has been
1974 compiled for and run from there. The address for which kernel is
1975 compiled already meets above alignment restrictions. Hence the
1976 end result is that kernel runs from a physical address meeting
1977 above alignment restrictions.
1978
1979 On 32-bit this value must be a multiple of 0x2000. On 64-bit
1980 this value must be a multiple of 0x200000.
1981
1982 Don't change this unless you know what you are doing.
1983
1984 config HOTPLUG_CPU
1985 bool "Support for hot-pluggable CPUs"
1986 depends on SMP
1987 ---help---
1988 Say Y here to allow turning CPUs off and on. CPUs can be
1989 controlled through /sys/devices/system/cpu.
1990 ( Note: power management support will enable this option
1991 automatically on SMP systems. )
1992 Say N if you want to disable CPU hotplug.
1993
1994 config BOOTPARAM_HOTPLUG_CPU0
1995 bool "Set default setting of cpu0_hotpluggable"
1996 default n
1997 depends on HOTPLUG_CPU
1998 ---help---
1999 Set whether default state of cpu0_hotpluggable is on or off.
2000
2001 Say Y here to enable CPU0 hotplug by default. If this switch
2002 is turned on, there is no need to give cpu0_hotplug kernel
2003 parameter and the CPU0 hotplug feature is enabled by default.
2004
2005 Please note: there are two known CPU0 dependencies if you want
2006 to enable the CPU0 hotplug feature either by this switch or by
2007 cpu0_hotplug kernel parameter.
2008
2009 First, resume from hibernate or suspend always starts from CPU0.
2010 So hibernate and suspend are prevented if CPU0 is offline.
2011
2012 Second dependency is PIC interrupts always go to CPU0. CPU0 can not
2013 offline if any interrupt can not migrate out of CPU0. There may
2014 be other CPU0 dependencies.
2015
2016 Please make sure the dependencies are under your control before
2017 you enable this feature.
2018
2019 Say N if you don't want to enable CPU0 hotplug feature by default.
2020 You still can enable the CPU0 hotplug feature at boot by kernel
2021 parameter cpu0_hotplug.
2022
2023 config DEBUG_HOTPLUG_CPU0
2024 def_bool n
2025 prompt "Debug CPU0 hotplug"
2026 depends on HOTPLUG_CPU
2027 ---help---
2028 Enabling this option offlines CPU0 (if CPU0 can be offlined) as
2029 soon as possible and boots up userspace with CPU0 offlined. User
2030 can online CPU0 back after boot time.
2031
2032 To debug CPU0 hotplug, you need to enable CPU0 offline/online
2033 feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during
2034 compilation or giving cpu0_hotplug kernel parameter at boot.
2035
2036 If unsure, say N.
2037
2038 config COMPAT_VDSO
2039 def_bool n
2040 prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
2041 depends on X86_32 || IA32_EMULATION
2042 ---help---
2043 Certain buggy versions of glibc will crash if they are
2044 presented with a 32-bit vDSO that is not mapped at the address
2045 indicated in its segment table.
2046
2047 The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a
2048 and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and
2049 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is
2050 the only released version with the bug, but OpenSUSE 9
2051 contains a buggy "glibc 2.3.2".
2052
2053 The symptom of the bug is that everything crashes on startup, saying:
2054 dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed!
2055
2056 Saying Y here changes the default value of the vdso32 boot
2057 option from 1 to 0, which turns off the 32-bit vDSO entirely.
2058 This works around the glibc bug but hurts performance.
2059
2060 If unsure, say N: if you are compiling your own kernel, you
2061 are unlikely to be using a buggy version of glibc.
2062
2063 choice
2064 prompt "vsyscall table for legacy applications"
2065 depends on X86_64
2066 default LEGACY_VSYSCALL_EMULATE
2067 help
2068 Legacy user code that does not know how to find the vDSO expects
2069 to be able to issue three syscalls by calling fixed addresses in
2070 kernel space. Since this location is not randomized with ASLR,
2071 it can be used to assist security vulnerability exploitation.
2072
2073 This setting can be changed at boot time via the kernel command
2074 line parameter vsyscall=[native|emulate|none].
2075
2076 On a system with recent enough glibc (2.14 or newer) and no
2077 static binaries, you can say None without a performance penalty
2078 to improve security.
2079
2080 If unsure, select "Emulate".
2081
2082 config LEGACY_VSYSCALL_NATIVE
2083 bool "Native"
2084 help
2085 Actual executable code is located in the fixed vsyscall
2086 address mapping, implementing time() efficiently. Since
2087 this makes the mapping executable, it can be used during
2088 security vulnerability exploitation (traditionally as
2089 ROP gadgets). This configuration is not recommended.
2090
2091 config LEGACY_VSYSCALL_EMULATE
2092 bool "Emulate"
2093 help
2094 The kernel traps and emulates calls into the fixed
2095 vsyscall address mapping. This makes the mapping
2096 non-executable, but it still contains known contents,
2097 which could be used in certain rare security vulnerability
2098 exploits. This configuration is recommended when userspace
2099 still uses the vsyscall area.
2100
2101 config LEGACY_VSYSCALL_NONE
2102 bool "None"
2103 help
2104 There will be no vsyscall mapping at all. This will
2105 eliminate any risk of ASLR bypass due to the vsyscall
2106 fixed address mapping. Attempts to use the vsyscalls
2107 will be reported to dmesg, so that either old or
2108 malicious userspace programs can be identified.
2109
2110 endchoice
2111
2112 config CMDLINE_BOOL
2113 bool "Built-in kernel command line"
2114 ---help---
2115 Allow for specifying boot arguments to the kernel at
2116 build time. On some systems (e.g. embedded ones), it is
2117 necessary or convenient to provide some or all of the
2118 kernel boot arguments with the kernel itself (that is,
2119 to not rely on the boot loader to provide them.)
2120
2121 To compile command line arguments into the kernel,
2122 set this option to 'Y', then fill in the
2123 boot arguments in CONFIG_CMDLINE.
2124
2125 Systems with fully functional boot loaders (i.e. non-embedded)
2126 should leave this option set to 'N'.
2127
2128 config CMDLINE
2129 string "Built-in kernel command string"
2130 depends on CMDLINE_BOOL
2131 default ""
2132 ---help---
2133 Enter arguments here that should be compiled into the kernel
2134 image and used at boot time. If the boot loader provides a
2135 command line at boot time, it is appended to this string to
2136 form the full kernel command line, when the system boots.
2137
2138 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
2139 change this behavior.
2140
2141 In most cases, the command line (whether built-in or provided
2142 by the boot loader) should specify the device for the root
2143 file system.
2144
2145 config CMDLINE_OVERRIDE
2146 bool "Built-in command line overrides boot loader arguments"
2147 depends on CMDLINE_BOOL
2148 ---help---
2149 Set this option to 'Y' to have the kernel ignore the boot loader
2150 command line, and use ONLY the built-in command line.
2151
2152 This is used to work around broken boot loaders. This should
2153 be set to 'N' under normal conditions.
2154
2155 config MODIFY_LDT_SYSCALL
2156 bool "Enable the LDT (local descriptor table)" if EXPERT
2157 default y
2158 ---help---
2159 Linux can allow user programs to install a per-process x86
2160 Local Descriptor Table (LDT) using the modify_ldt(2) system
2161 call. This is required to run 16-bit or segmented code such as
2162 DOSEMU or some Wine programs. It is also used by some very old
2163 threading libraries.
2164
2165 Enabling this feature adds a small amount of overhead to
2166 context switches and increases the low-level kernel attack
2167 surface. Disabling it removes the modify_ldt(2) system call.
2168
2169 Saying 'N' here may make sense for embedded or server kernels.
2170
2171 source "kernel/livepatch/Kconfig"
2172
2173 endmenu
2174
2175 config ARCH_ENABLE_MEMORY_HOTPLUG
2176 def_bool y
2177 depends on X86_64 || (X86_32 && HIGHMEM)
2178
2179 config ARCH_ENABLE_MEMORY_HOTREMOVE
2180 def_bool y
2181 depends on MEMORY_HOTPLUG
2182
2183 config USE_PERCPU_NUMA_NODE_ID
2184 def_bool y
2185 depends on NUMA
2186
2187 config ARCH_ENABLE_SPLIT_PMD_PTLOCK
2188 def_bool y
2189 depends on X86_64 || X86_PAE
2190
2191 config ARCH_ENABLE_HUGEPAGE_MIGRATION
2192 def_bool y
2193 depends on X86_64 && HUGETLB_PAGE && MIGRATION
2194
2195 menu "Power management and ACPI options"
2196
2197 config ARCH_HIBERNATION_HEADER
2198 def_bool y
2199 depends on X86_64 && HIBERNATION
2200
2201 source "kernel/power/Kconfig"
2202
2203 source "drivers/acpi/Kconfig"
2204
2205 source "drivers/sfi/Kconfig"
2206
2207 config X86_APM_BOOT
2208 def_bool y
2209 depends on APM
2210
2211 menuconfig APM
2212 tristate "APM (Advanced Power Management) BIOS support"
2213 depends on X86_32 && PM_SLEEP
2214 ---help---
2215 APM is a BIOS specification for saving power using several different
2216 techniques. This is mostly useful for battery powered laptops with
2217 APM compliant BIOSes. If you say Y here, the system time will be
2218 reset after a RESUME operation, the /proc/apm device will provide
2219 battery status information, and user-space programs will receive
2220 notification of APM "events" (e.g. battery status change).
2221
2222 If you select "Y" here, you can disable actual use of the APM
2223 BIOS by passing the "apm=off" option to the kernel at boot time.
2224
2225 Note that the APM support is almost completely disabled for
2226 machines with more than one CPU.
2227
2228 In order to use APM, you will need supporting software. For location
2229 and more information, read <file:Documentation/power/apm-acpi.txt>
2230 and the Battery Powered Linux mini-HOWTO, available from
2231 <http://www.tldp.org/docs.html#howto>.
2232
2233 This driver does not spin down disk drives (see the hdparm(8)
2234 manpage ("man 8 hdparm") for that), and it doesn't turn off
2235 VESA-compliant "green" monitors.
2236
2237 This driver does not support the TI 4000M TravelMate and the ACER
2238 486/DX4/75 because they don't have compliant BIOSes. Many "green"
2239 desktop machines also don't have compliant BIOSes, and this driver
2240 may cause those machines to panic during the boot phase.
2241
2242 Generally, if you don't have a battery in your machine, there isn't
2243 much point in using this driver and you should say N. If you get
2244 random kernel OOPSes or reboots that don't seem to be related to
2245 anything, try disabling/enabling this option (or disabling/enabling
2246 APM in your BIOS).
2247
2248 Some other things you should try when experiencing seemingly random,
2249 "weird" problems:
2250
2251 1) make sure that you have enough swap space and that it is
2252 enabled.
2253 2) pass the "no-hlt" option to the kernel
2254 3) switch on floating point emulation in the kernel and pass
2255 the "no387" option to the kernel
2256 4) pass the "floppy=nodma" option to the kernel
2257 5) pass the "mem=4M" option to the kernel (thereby disabling
2258 all but the first 4 MB of RAM)
2259 6) make sure that the CPU is not over clocked.
2260 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
2261 8) disable the cache from your BIOS settings
2262 9) install a fan for the video card or exchange video RAM
2263 10) install a better fan for the CPU
2264 11) exchange RAM chips
2265 12) exchange the motherboard.
2266
2267 To compile this driver as a module, choose M here: the
2268 module will be called apm.
2269
2270 if APM
2271
2272 config APM_IGNORE_USER_SUSPEND
2273 bool "Ignore USER SUSPEND"
2274 ---help---
2275 This option will ignore USER SUSPEND requests. On machines with a
2276 compliant APM BIOS, you want to say N. However, on the NEC Versa M
2277 series notebooks, it is necessary to say Y because of a BIOS bug.
2278
2279 config APM_DO_ENABLE
2280 bool "Enable PM at boot time"
2281 ---help---
2282 Enable APM features at boot time. From page 36 of the APM BIOS
2283 specification: "When disabled, the APM BIOS does not automatically
2284 power manage devices, enter the Standby State, enter the Suspend
2285 State, or take power saving steps in response to CPU Idle calls."
2286 This driver will make CPU Idle calls when Linux is idle (unless this
2287 feature is turned off -- see "Do CPU IDLE calls", below). This
2288 should always save battery power, but more complicated APM features
2289 will be dependent on your BIOS implementation. You may need to turn
2290 this option off if your computer hangs at boot time when using APM
2291 support, or if it beeps continuously instead of suspending. Turn
2292 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
2293 T400CDT. This is off by default since most machines do fine without
2294 this feature.
2295
2296 config APM_CPU_IDLE
2297 depends on CPU_IDLE
2298 bool "Make CPU Idle calls when idle"
2299 ---help---
2300 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
2301 On some machines, this can activate improved power savings, such as
2302 a slowed CPU clock rate, when the machine is idle. These idle calls
2303 are made after the idle loop has run for some length of time (e.g.,
2304 333 mS). On some machines, this will cause a hang at boot time or
2305 whenever the CPU becomes idle. (On machines with more than one CPU,
2306 this option does nothing.)
2307
2308 config APM_DISPLAY_BLANK
2309 bool "Enable console blanking using APM"
2310 ---help---
2311 Enable console blanking using the APM. Some laptops can use this to
2312 turn off the LCD backlight when the screen blanker of the Linux
2313 virtual console blanks the screen. Note that this is only used by
2314 the virtual console screen blanker, and won't turn off the backlight
2315 when using the X Window system. This also doesn't have anything to
2316 do with your VESA-compliant power-saving monitor. Further, this
2317 option doesn't work for all laptops -- it might not turn off your
2318 backlight at all, or it might print a lot of errors to the console,
2319 especially if you are using gpm.
2320
2321 config APM_ALLOW_INTS
2322 bool "Allow interrupts during APM BIOS calls"
2323 ---help---
2324 Normally we disable external interrupts while we are making calls to
2325 the APM BIOS as a measure to lessen the effects of a badly behaving
2326 BIOS implementation. The BIOS should reenable interrupts if it
2327 needs to. Unfortunately, some BIOSes do not -- especially those in
2328 many of the newer IBM Thinkpads. If you experience hangs when you
2329 suspend, try setting this to Y. Otherwise, say N.
2330
2331 endif # APM
2332
2333 source "drivers/cpufreq/Kconfig"
2334
2335 source "drivers/cpuidle/Kconfig"
2336
2337 source "drivers/idle/Kconfig"
2338
2339 endmenu
2340
2341
2342 menu "Bus options (PCI etc.)"
2343
2344 config PCI
2345 bool "PCI support"
2346 default y
2347 ---help---
2348 Find out whether you have a PCI motherboard. PCI is the name of a
2349 bus system, i.e. the way the CPU talks to the other stuff inside
2350 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
2351 VESA. If you have PCI, say Y, otherwise N.
2352
2353 choice
2354 prompt "PCI access mode"
2355 depends on X86_32 && PCI
2356 default PCI_GOANY
2357 ---help---
2358 On PCI systems, the BIOS can be used to detect the PCI devices and
2359 determine their configuration. However, some old PCI motherboards
2360 have BIOS bugs and may crash if this is done. Also, some embedded
2361 PCI-based systems don't have any BIOS at all. Linux can also try to
2362 detect the PCI hardware directly without using the BIOS.
2363
2364 With this option, you can specify how Linux should detect the
2365 PCI devices. If you choose "BIOS", the BIOS will be used,
2366 if you choose "Direct", the BIOS won't be used, and if you
2367 choose "MMConfig", then PCI Express MMCONFIG will be used.
2368 If you choose "Any", the kernel will try MMCONFIG, then the
2369 direct access method and falls back to the BIOS if that doesn't
2370 work. If unsure, go with the default, which is "Any".
2371
2372 config PCI_GOBIOS
2373 bool "BIOS"
2374
2375 config PCI_GOMMCONFIG
2376 bool "MMConfig"
2377
2378 config PCI_GODIRECT
2379 bool "Direct"
2380
2381 config PCI_GOOLPC
2382 bool "OLPC XO-1"
2383 depends on OLPC
2384
2385 config PCI_GOANY
2386 bool "Any"
2387
2388 endchoice
2389
2390 config PCI_BIOS
2391 def_bool y
2392 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
2393
2394 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
2395 config PCI_DIRECT
2396 def_bool y
2397 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG))
2398
2399 config PCI_MMCONFIG
2400 def_bool y
2401 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
2402
2403 config PCI_OLPC
2404 def_bool y
2405 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
2406
2407 config PCI_XEN
2408 def_bool y
2409 depends on PCI && XEN
2410 select SWIOTLB_XEN
2411
2412 config PCI_DOMAINS
2413 def_bool y
2414 depends on PCI
2415
2416 config PCI_MMCONFIG
2417 bool "Support mmconfig PCI config space access"
2418 depends on X86_64 && PCI && ACPI
2419
2420 config PCI_CNB20LE_QUIRK
2421 bool "Read CNB20LE Host Bridge Windows" if EXPERT
2422 depends on PCI
2423 help
2424 Read the PCI windows out of the CNB20LE host bridge. This allows
2425 PCI hotplug to work on systems with the CNB20LE chipset which do
2426 not have ACPI.
2427
2428 There's no public spec for this chipset, and this functionality
2429 is known to be incomplete.
2430
2431 You should say N unless you know you need this.
2432
2433 source "drivers/pci/pcie/Kconfig"
2434
2435 source "drivers/pci/Kconfig"
2436
2437 # x86_64 have no ISA slots, but can have ISA-style DMA.
2438 config ISA_DMA_API
2439 bool "ISA-style DMA support" if (X86_64 && EXPERT)
2440 default y
2441 help
2442 Enables ISA-style DMA support for devices requiring such controllers.
2443 If unsure, say Y.
2444
2445 if X86_32
2446
2447 config ISA
2448 bool "ISA support"
2449 ---help---
2450 Find out whether you have ISA slots on your motherboard. ISA is the
2451 name of a bus system, i.e. the way the CPU talks to the other stuff
2452 inside your box. Other bus systems are PCI, EISA, MicroChannel
2453 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2454 newer boards don't support it. If you have ISA, say Y, otherwise N.
2455
2456 config EISA
2457 bool "EISA support"
2458 depends on ISA
2459 ---help---
2460 The Extended Industry Standard Architecture (EISA) bus was
2461 developed as an open alternative to the IBM MicroChannel bus.
2462
2463 The EISA bus provided some of the features of the IBM MicroChannel
2464 bus while maintaining backward compatibility with cards made for
2465 the older ISA bus. The EISA bus saw limited use between 1988 and
2466 1995 when it was made obsolete by the PCI bus.
2467
2468 Say Y here if you are building a kernel for an EISA-based machine.
2469
2470 Otherwise, say N.
2471
2472 source "drivers/eisa/Kconfig"
2473
2474 config SCx200
2475 tristate "NatSemi SCx200 support"
2476 ---help---
2477 This provides basic support for National Semiconductor's
2478 (now AMD's) Geode processors. The driver probes for the
2479 PCI-IDs of several on-chip devices, so its a good dependency
2480 for other scx200_* drivers.
2481
2482 If compiled as a module, the driver is named scx200.
2483
2484 config SCx200HR_TIMER
2485 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2486 depends on SCx200
2487 default y
2488 ---help---
2489 This driver provides a clocksource built upon the on-chip
2490 27MHz high-resolution timer. Its also a workaround for
2491 NSC Geode SC-1100's buggy TSC, which loses time when the
2492 processor goes idle (as is done by the scheduler). The
2493 other workaround is idle=poll boot option.
2494
2495 config OLPC
2496 bool "One Laptop Per Child support"
2497 depends on !X86_PAE
2498 select GPIOLIB
2499 select OF
2500 select OF_PROMTREE
2501 select IRQ_DOMAIN
2502 ---help---
2503 Add support for detecting the unique features of the OLPC
2504 XO hardware.
2505
2506 config OLPC_XO1_PM
2507 bool "OLPC XO-1 Power Management"
2508 depends on OLPC && MFD_CS5535 && PM_SLEEP
2509 select MFD_CORE
2510 ---help---
2511 Add support for poweroff and suspend of the OLPC XO-1 laptop.
2512
2513 config OLPC_XO1_RTC
2514 bool "OLPC XO-1 Real Time Clock"
2515 depends on OLPC_XO1_PM && RTC_DRV_CMOS
2516 ---help---
2517 Add support for the XO-1 real time clock, which can be used as a
2518 programmable wakeup source.
2519
2520 config OLPC_XO1_SCI
2521 bool "OLPC XO-1 SCI extras"
2522 depends on OLPC && OLPC_XO1_PM
2523 depends on INPUT=y
2524 select POWER_SUPPLY
2525 select GPIO_CS5535
2526 select MFD_CORE
2527 ---help---
2528 Add support for SCI-based features of the OLPC XO-1 laptop:
2529 - EC-driven system wakeups
2530 - Power button
2531 - Ebook switch
2532 - Lid switch
2533 - AC adapter status updates
2534 - Battery status updates
2535
2536 config OLPC_XO15_SCI
2537 bool "OLPC XO-1.5 SCI extras"
2538 depends on OLPC && ACPI
2539 select POWER_SUPPLY
2540 ---help---
2541 Add support for SCI-based features of the OLPC XO-1.5 laptop:
2542 - EC-driven system wakeups
2543 - AC adapter status updates
2544 - Battery status updates
2545
2546 config ALIX
2547 bool "PCEngines ALIX System Support (LED setup)"
2548 select GPIOLIB
2549 ---help---
2550 This option enables system support for the PCEngines ALIX.
2551 At present this just sets up LEDs for GPIO control on
2552 ALIX2/3/6 boards. However, other system specific setup should
2553 get added here.
2554
2555 Note: You must still enable the drivers for GPIO and LED support
2556 (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs
2557
2558 Note: You have to set alix.force=1 for boards with Award BIOS.
2559
2560 config NET5501
2561 bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
2562 select GPIOLIB
2563 ---help---
2564 This option enables system support for the Soekris Engineering net5501.
2565
2566 config GEOS
2567 bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
2568 select GPIOLIB
2569 depends on DMI
2570 ---help---
2571 This option enables system support for the Traverse Technologies GEOS.
2572
2573 config TS5500
2574 bool "Technologic Systems TS-5500 platform support"
2575 depends on MELAN
2576 select CHECK_SIGNATURE
2577 select NEW_LEDS
2578 select LEDS_CLASS
2579 ---help---
2580 This option enables system support for the Technologic Systems TS-5500.
2581
2582 endif # X86_32
2583
2584 config AMD_NB
2585 def_bool y
2586 depends on CPU_SUP_AMD && PCI
2587
2588 source "drivers/pcmcia/Kconfig"
2589
2590 source "drivers/pci/hotplug/Kconfig"
2591
2592 config RAPIDIO
2593 tristate "RapidIO support"
2594 depends on PCI
2595 default n
2596 help
2597 If enabled this option will include drivers and the core
2598 infrastructure code to support RapidIO interconnect devices.
2599
2600 source "drivers/rapidio/Kconfig"
2601
2602 config X86_SYSFB
2603 bool "Mark VGA/VBE/EFI FB as generic system framebuffer"
2604 help
2605 Firmwares often provide initial graphics framebuffers so the BIOS,
2606 bootloader or kernel can show basic video-output during boot for
2607 user-guidance and debugging. Historically, x86 used the VESA BIOS
2608 Extensions and EFI-framebuffers for this, which are mostly limited
2609 to x86.
2610 This option, if enabled, marks VGA/VBE/EFI framebuffers as generic
2611 framebuffers so the new generic system-framebuffer drivers can be
2612 used on x86. If the framebuffer is not compatible with the generic
2613 modes, it is adverticed as fallback platform framebuffer so legacy
2614 drivers like efifb, vesafb and uvesafb can pick it up.
2615 If this option is not selected, all system framebuffers are always
2616 marked as fallback platform framebuffers as usual.
2617
2618 Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will
2619 not be able to pick up generic system framebuffers if this option
2620 is selected. You are highly encouraged to enable simplefb as
2621 replacement if you select this option. simplefb can correctly deal
2622 with generic system framebuffers. But you should still keep vesafb
2623 and others enabled as fallback if a system framebuffer is
2624 incompatible with simplefb.
2625
2626 If unsure, say Y.
2627
2628 endmenu
2629
2630
2631 menu "Executable file formats / Emulations"
2632
2633 source "fs/Kconfig.binfmt"
2634
2635 config IA32_EMULATION
2636 bool "IA32 Emulation"
2637 depends on X86_64
2638 select BINFMT_ELF
2639 select COMPAT_BINFMT_ELF
2640 select ARCH_WANT_OLD_COMPAT_IPC
2641 ---help---
2642 Include code to run legacy 32-bit programs under a
2643 64-bit kernel. You should likely turn this on, unless you're
2644 100% sure that you don't have any 32-bit programs left.
2645
2646 config IA32_AOUT
2647 tristate "IA32 a.out support"
2648 depends on IA32_EMULATION
2649 ---help---
2650 Support old a.out binaries in the 32bit emulation.
2651
2652 config X86_X32
2653 bool "x32 ABI for 64-bit mode"
2654 depends on X86_64
2655 ---help---
2656 Include code to run binaries for the x32 native 32-bit ABI
2657 for 64-bit processors. An x32 process gets access to the
2658 full 64-bit register file and wide data path while leaving
2659 pointers at 32 bits for smaller memory footprint.
2660
2661 You will need a recent binutils (2.22 or later) with
2662 elf32_x86_64 support enabled to compile a kernel with this
2663 option set.
2664
2665 config COMPAT
2666 def_bool y
2667 depends on IA32_EMULATION || X86_X32
2668
2669 if COMPAT
2670 config COMPAT_FOR_U64_ALIGNMENT
2671 def_bool y
2672
2673 config SYSVIPC_COMPAT
2674 def_bool y
2675 depends on SYSVIPC
2676
2677 config KEYS_COMPAT
2678 def_bool y
2679 depends on KEYS
2680 endif
2681
2682 endmenu
2683
2684
2685 config HAVE_ATOMIC_IOMAP
2686 def_bool y
2687 depends on X86_32
2688
2689 config X86_DEV_DMA_OPS
2690 bool
2691 depends on X86_64 || STA2X11
2692
2693 config X86_DMA_REMAP
2694 bool
2695 depends on STA2X11
2696
2697 config PMC_ATOM
2698 def_bool y
2699 depends on PCI
2700
2701 config VMD
2702 depends on PCI_MSI
2703 tristate "Volume Management Device Driver"
2704 default N
2705 ---help---
2706 Adds support for the Intel Volume Management Device (VMD). VMD is a
2707 secondary PCI host bridge that allows PCI Express root ports,
2708 and devices attached to them, to be removed from the default
2709 PCI domain and placed within the VMD domain. This provides
2710 more bus resources than are otherwise possible with a
2711 single domain. If you know your system provides one of these and
2712 has devices attached to it, say Y; if you are not sure, say N.
2713
2714 source "net/Kconfig"
2715
2716 source "drivers/Kconfig"
2717
2718 source "drivers/firmware/Kconfig"
2719
2720 source "fs/Kconfig"
2721
2722 source "arch/x86/Kconfig.debug"
2723
2724 source "security/Kconfig"
2725
2726 source "crypto/Kconfig"
2727
2728 source "arch/x86/kvm/Kconfig"
2729
2730 source "lib/Kconfig"