kbuild: migrate all arch to the kconfig mainmenu upgrade
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / arch / x86 / Kconfig
CommitLineData
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1# Select 32 or 64 bit
2config 64BIT
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3 bool "64-bit kernel" if ARCH = "x86"
4 default ARCH = "x86_64"
8f9ca475 5 ---help---
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6 Say yes to build a 64-bit kernel - formerly known as x86_64
7 Say no to build a 32-bit kernel - formerly known as i386
8
9config X86_32
10 def_bool !64BIT
11
12config X86_64
13 def_bool 64BIT
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14
15### Arch settings
8d5fffb9 16config X86
3c2362e6 17 def_bool y
e17c6d56 18 select HAVE_AOUT if X86_32
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19 select HAVE_READQ
20 select HAVE_WRITEQ
a5574cf6 21 select HAVE_UNSTABLE_SCHED_CLOCK
ec7748b5 22 select HAVE_IDE
42d4b839 23 select HAVE_OPROFILE
cdd6c482 24 select HAVE_PERF_EVENTS if (!M386 && !M486)
28b2ee20 25 select HAVE_IOREMAP_PROT
3f550096 26 select HAVE_KPROBES
1f972768 27 select ARCH_WANT_OPTIONAL_GPIOLIB
da4276b8 28 select ARCH_WANT_FRAME_POINTERS
7c095e46 29 select HAVE_DMA_ATTRS
9edddaa2 30 select HAVE_KRETPROBES
c0f7ac3a 31 select HAVE_OPTPROBES
e4b2b886 32 select HAVE_FTRACE_MCOUNT_RECORD
677aa9f7 33 select HAVE_DYNAMIC_FTRACE
606576ce 34 select HAVE_FUNCTION_TRACER
48d68b20 35 select HAVE_FUNCTION_GRAPH_TRACER
71e308a2 36 select HAVE_FUNCTION_GRAPH_FP_TEST
60a7ecf4 37 select HAVE_FUNCTION_TRACE_MCOUNT_TEST
9a5fd902 38 select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
66700001 39 select HAVE_SYSCALL_TRACEPOINTS
e0ec9483 40 select HAVE_KVM
49793b03 41 select HAVE_ARCH_KGDB
99bbc4b1 42 select HAVE_ARCH_TRACEHOOK
323ec001 43 select HAVE_GENERIC_DMA_COHERENT if X86_32
58340a07 44 select HAVE_EFFICIENT_UNALIGNED_ACCESS
8d26487f 45 select USER_STACKTRACE_SUPPORT
f850c30c 46 select HAVE_REGS_AND_STACK_ACCESS_API
2118d0c5 47 select HAVE_DMA_API_DEBUG
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48 select HAVE_KERNEL_GZIP
49 select HAVE_KERNEL_BZIP2
50 select HAVE_KERNEL_LZMA
13510997 51 select HAVE_KERNEL_LZO
0067f129 52 select HAVE_HW_BREAKPOINT
0102752e 53 select HAVE_MIXED_BREAKPOINTS_REGS
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54 select PERF_EVENTS
55 select ANON_INODES
0a4af3b0 56 select HAVE_ARCH_KMEMCHECK
7c68af6e 57 select HAVE_USER_RETURN_NOTIFIER
7d8330a5 58
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59config INSTRUCTION_DECODER
60 def_bool (KPROBES || PERF_EVENTS)
61
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62config OUTPUT_FORMAT
63 string
64 default "elf32-i386" if X86_32
65 default "elf64-x86-64" if X86_64
66
73531905 67config ARCH_DEFCONFIG
b9b39bfb 68 string
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SR
69 default "arch/x86/configs/i386_defconfig" if X86_32
70 default "arch/x86/configs/x86_64_defconfig" if X86_64
b9b39bfb 71
8d5fffb9 72config GENERIC_TIME
3c2362e6 73 def_bool y
8d5fffb9
SR
74
75config GENERIC_CMOS_UPDATE
3c2362e6 76 def_bool y
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77
78config CLOCKSOURCE_WATCHDOG
3c2362e6 79 def_bool y
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80
81config GENERIC_CLOCKEVENTS
3c2362e6 82 def_bool y
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83
84config GENERIC_CLOCKEVENTS_BROADCAST
3c2362e6 85 def_bool y
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86 depends on X86_64 || (X86_32 && X86_LOCAL_APIC)
87
88config LOCKDEP_SUPPORT
3c2362e6 89 def_bool y
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90
91config STACKTRACE_SUPPORT
3c2362e6 92 def_bool y
8d5fffb9 93
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94config HAVE_LATENCYTOP_SUPPORT
95 def_bool y
96
8d5fffb9 97config MMU
3c2362e6 98 def_bool y
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99
100config ZONE_DMA
3c2362e6 101 def_bool y
8d5fffb9 102
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103config SBUS
104 bool
105
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106config NEED_DMA_MAP_STATE
107 def_bool (X86_64 || DMAR || DMA_API_DEBUG)
108
18e98307 109config NEED_SG_DMA_LENGTH
4a14d84e 110 def_bool y
18e98307 111
8d5fffb9 112config GENERIC_ISA_DMA
3c2362e6 113 def_bool y
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114
115config GENERIC_IOMAP
3c2362e6 116 def_bool y
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117
118config GENERIC_BUG
3c2362e6 119 def_bool y
8d5fffb9 120 depends on BUG
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121 select GENERIC_BUG_RELATIVE_POINTERS if X86_64
122
123config GENERIC_BUG_RELATIVE_POINTERS
124 bool
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125
126config GENERIC_HWEIGHT
3c2362e6 127 def_bool y
8d5fffb9 128
a6082959 129config GENERIC_GPIO
9ba16087 130 bool
a6082959 131
8d5fffb9 132config ARCH_MAY_HAVE_PC_FDC
3c2362e6 133 def_bool y
8d5fffb9 134
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135config RWSEM_GENERIC_SPINLOCK
136 def_bool !X86_XADD
137
138config RWSEM_XCHGADD_ALGORITHM
139 def_bool X86_XADD
140
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141config ARCH_HAS_CPU_IDLE_WAIT
142 def_bool y
143
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144config GENERIC_CALIBRATE_DELAY
145 def_bool y
146
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147config GENERIC_TIME_VSYSCALL
148 bool
149 default X86_64
150
9a0b8415 151config ARCH_HAS_CPU_RELAX
152 def_bool y
153
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154config ARCH_HAS_DEFAULT_IDLE
155 def_bool y
156
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157config ARCH_HAS_CACHE_LINE_SIZE
158 def_bool y
159
dd5af90a 160config HAVE_SETUP_PER_CPU_AREA
89c9c4c5 161 def_bool y
b32ef636 162
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163config NEED_PER_CPU_EMBED_FIRST_CHUNK
164 def_bool y
165
166config NEED_PER_CPU_PAGE_FIRST_CHUNK
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TH
167 def_bool y
168
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169config HAVE_CPUMASK_OF_CPU_MAP
170 def_bool X86_64_SMP
171
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172config ARCH_HIBERNATION_POSSIBLE
173 def_bool y
801e4062 174
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175config ARCH_SUSPEND_POSSIBLE
176 def_bool y
f4cb5700 177
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178config ZONE_DMA32
179 bool
180 default X86_64
181
182config ARCH_POPULATES_NODE_MAP
183 def_bool y
184
185config AUDIT_ARCH
186 bool
187 default X86_64
188
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189config ARCH_SUPPORTS_OPTIMIZED_INLINING
190 def_bool y
191
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192config ARCH_SUPPORTS_DEBUG_PAGEALLOC
193 def_bool y
194
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195config HAVE_EARLY_RES
196 def_bool y
197
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198config HAVE_INTEL_TXT
199 def_bool y
200 depends on EXPERIMENTAL && DMAR && ACPI
201
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202# Use the generic interrupt handling code in kernel/irq/:
203config GENERIC_HARDIRQS
6fc108a0 204 def_bool y
8d5fffb9 205
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206config GENERIC_HARDIRQS_NO__DO_IRQ
207 def_bool y
208
8d5fffb9 209config GENERIC_IRQ_PROBE
6fc108a0 210 def_bool y
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211
212config GENERIC_PENDING_IRQ
6fc108a0 213 def_bool y
8d5fffb9 214 depends on GENERIC_HARDIRQS && SMP
8d5fffb9 215
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216config USE_GENERIC_SMP_HELPERS
217 def_bool y
218 depends on SMP
219
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220config X86_32_SMP
221 def_bool y
222 depends on X86_32 && SMP
223
224config X86_64_SMP
225 def_bool y
226 depends on X86_64 && SMP
227
8d5fffb9 228config X86_HT
6fc108a0 229 def_bool y
ee0011a7 230 depends on SMP
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231
232config X86_TRAMPOLINE
6fc108a0 233 def_bool y
3e5095d1 234 depends on SMP || (64BIT && ACPI_SLEEP)
8d5fffb9 235
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236config X86_32_LAZY_GS
237 def_bool y
60a5317f 238 depends on X86_32 && !CC_STACKPROTECTOR
ccbeed3a 239
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240config ARCH_HWEIGHT_CFLAGS
241 string
242 default "-fcall-saved-ecx -fcall-saved-edx" if X86_32
243 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
244
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245config KTIME_SCALAR
246 def_bool X86_32
506f1d07 247source "init/Kconfig"
dc52ddc0 248source "kernel/Kconfig.freezer"
8d5fffb9 249
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250menu "Processor type and features"
251
252source "kernel/time/Kconfig"
253
254config SMP
255 bool "Symmetric multi-processing support"
256 ---help---
257 This enables support for systems with more than one CPU. If you have
258 a system with only one CPU, like most personal computers, say N. If
259 you have a system with more than one CPU, say Y.
260
261 If you say N here, the kernel will run on single and multiprocessor
262 machines, but will use only one CPU of a multiprocessor machine. If
263 you say Y here, the kernel will run on many, but not all,
264 singleprocessor machines. On a singleprocessor machine, the kernel
265 will run faster if you say N here.
266
267 Note that if you say Y here and choose architecture "586" or
268 "Pentium" under "Processor family", the kernel will not work on 486
269 architectures. Similarly, multiprocessor kernels for the "PPro"
270 architecture may not work on all Pentium based boards.
271
272 People using multiprocessor machines who say Y here should also say
273 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
274 Management" code will be disabled if you say Y here.
275
03502faa 276 See also <file:Documentation/i386/IO-APIC.txt>,
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277 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
278 <http://www.tldp.org/docs.html#howto>.
279
280 If you don't know what to do here, say N.
281
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282config X86_X2APIC
283 bool "Support x2apic"
f7d7f866 284 depends on X86_LOCAL_APIC && X86_64 && INTR_REMAP
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285 ---help---
286 This enables x2apic support on CPUs that have this feature.
287
288 This allows 32-bit apic IDs (so it can support very large systems),
289 and accesses the local apic via MSRs not via mmio.
290
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291 If you don't know what to do here, say N.
292
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293config SPARSE_IRQ
294 bool "Support sparse irq numbering"
17483a1f 295 depends on PCI_MSI || HT_IRQ
8f9ca475 296 ---help---
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297 This enables support for sparse irqs. This is useful for distro
298 kernels that want to define a high CONFIG_NR_CPUS value but still
299 want to have low kernel memory footprint on smaller machines.
0b8f1efa 300
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IM
301 ( Sparse IRQs can also be beneficial on NUMA boxes, as they spread
302 out the irq_desc[] array in a more NUMA-friendly way. )
303
304 If you don't know what to do here, say N.
0b8f1efa 305
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306config NUMA_IRQ_DESC
307 def_bool y
b9098957 308 depends on SPARSE_IRQ && NUMA
48a1b10a 309
6695c85b 310config X86_MPPARSE
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311 bool "Enable MPS table" if ACPI
312 default y
5ab74722 313 depends on X86_LOCAL_APIC
8f9ca475 314 ---help---
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315 For old smp systems that do not have proper acpi support. Newer systems
316 (esp with 64bit cpus) with acpi support, MADT and DSDT will override it
6695c85b 317
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318config X86_BIGSMP
319 bool "Support for big SMP systems with more than 8 CPUs"
320 depends on X86_32 && SMP
8f9ca475 321 ---help---
26f7ef14 322 This option is needed for the systems that have more than 8 CPUs
506f1d07 323
8425091f 324if X86_32
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325config X86_EXTENDED_PLATFORM
326 bool "Support for extended (non-PC) x86 platforms"
327 default y
8f9ca475 328 ---help---
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IM
329 If you disable this option then the kernel will only support
330 standard PC platforms. (which covers the vast majority of
331 systems out there.)
332
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333 If you enable this option then you'll be able to select support
334 for the following (non-PC) 32 bit x86 platforms:
335 AMD Elan
336 NUMAQ (IBM/Sequent)
337 RDC R-321x SoC
338 SGI 320/540 (Visual Workstation)
339 Summit/EXA (IBM x440)
340 Unisys ES7000 IA32 series
3f4110a4 341 Moorestown MID devices
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342
343 If you have one of these systems, or if you want to build a
344 generic distribution kernel, say Y here - otherwise say N.
8425091f 345endif
06ac8346 346
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347if X86_64
348config X86_EXTENDED_PLATFORM
349 bool "Support for extended (non-PC) x86 platforms"
350 default y
351 ---help---
352 If you disable this option then the kernel will only support
353 standard PC platforms. (which covers the vast majority of
354 systems out there.)
355
356 If you enable this option then you'll be able to select support
357 for the following (non-PC) 64 bit x86 platforms:
358 ScaleMP vSMP
359 SGI Ultraviolet
360
361 If you have one of these systems, or if you want to build a
362 generic distribution kernel, say Y here - otherwise say N.
363endif
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364# This is an alphabetically sorted list of 64 bit extended platforms
365# Please maintain the alphabetic order if and when there are additions
506f1d07 366
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367config X86_VSMP
368 bool "ScaleMP vSMP"
369 select PARAVIRT
370 depends on X86_64 && PCI
371 depends on X86_EXTENDED_PLATFORM
8f9ca475 372 ---help---
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373 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
374 supposed to run on these EM64T-based machines. Only choose this option
375 if you have one of these machines.
5e3a77e9 376
03b48632
NP
377config X86_UV
378 bool "SGI Ultraviolet"
379 depends on X86_64
c5c606d9 380 depends on X86_EXTENDED_PLATFORM
54c28d29 381 depends on NUMA
9d6c26e7 382 depends on X86_X2APIC
8f9ca475 383 ---help---
03b48632
NP
384 This option is needed in order to support SGI Ultraviolet systems.
385 If you don't have one of these, you should say N here.
386
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387# Following is an alphabetically sorted list of 32 bit extended platforms
388# Please maintain the alphabetic order if and when there are additions
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SR
389
390config X86_ELAN
391 bool "AMD Elan"
392 depends on X86_32
c5c606d9 393 depends on X86_EXTENDED_PLATFORM
8f9ca475 394 ---help---
506f1d07
SR
395 Select this for an AMD Elan processor.
396
397 Do not use this option for K6/Athlon/Opteron processors!
398
399 If unsure, choose "PC-compatible" instead.
400
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401config X86_MRST
402 bool "Moorestown MID platform"
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403 depends on PCI
404 depends on PCI_GOANY
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405 depends on X86_32
406 depends on X86_EXTENDED_PLATFORM
4b2f3f7d 407 depends on X86_IO_APIC
bb24c471 408 select APB_TIMER
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TG
409 ---help---
410 Moorestown is Intel's Low Power Intel Architecture (LPIA) based Moblin
411 Internet Device(MID) platform. Moorestown consists of two chips:
412 Lincroft (CPU core, graphics, and memory controller) and Langwell IOH.
413 Unlike standard x86 PCs, Moorestown does not have many legacy devices
414 nor standard legacy replacement devices/features. e.g. Moorestown does
415 not contain i8259, i8254, HPET, legacy BIOS, most of the io ports.
416
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417config X86_RDC321X
418 bool "RDC R-321x SoC"
506f1d07 419 depends on X86_32
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420 depends on X86_EXTENDED_PLATFORM
421 select M486
422 select X86_REBOOTFIXUPS
423 ---help---
424 This option is needed for RDC R-321x system-on-chip, also known
425 as R-8610-(G).
426 If you don't have one of these chips, you should say N here.
427
e0c7ae37 428config X86_32_NON_STANDARD
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429 bool "Support non-standard 32-bit SMP architectures"
430 depends on X86_32 && SMP
c5c606d9 431 depends on X86_EXTENDED_PLATFORM
8f9ca475
IM
432 ---help---
433 This option compiles in the NUMAQ, Summit, bigsmp, ES7000, default
d49c4288
YL
434 subarchitectures. It is intended for a generic binary kernel.
435 if you select them all, kernel will probe it one by one. and will
436 fallback to default.
437
c5c606d9 438# Alphabetically sorted list of Non standard 32 bit platforms
d49c4288 439
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SR
440config X86_NUMAQ
441 bool "NUMAQ (IBM/Sequent)"
e0c7ae37 442 depends on X86_32_NON_STANDARD
a92d152e 443 depends on PCI
506f1d07 444 select NUMA
9c398017 445 select X86_MPPARSE
8f9ca475 446 ---help---
d49c4288
YL
447 This option is used for getting Linux to run on a NUMAQ (IBM/Sequent)
448 NUMA multiquad box. This changes the way that processors are
449 bootstrapped, and uses Clustered Logical APIC addressing mode instead
450 of Flat Logical. You will need a new lynxer.elf file to flash your
451 firmware with - send email to <Martin.Bligh@us.ibm.com>.
506f1d07 452
d949f36f 453config X86_SUPPORTS_MEMORY_FAILURE
6fc108a0 454 def_bool y
d949f36f
LT
455 # MCE code calls memory_failure():
456 depends on X86_MCE
457 # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags:
458 depends on !X86_NUMAQ
459 # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH:
460 depends on X86_64 || !SPARSEMEM
461 select ARCH_SUPPORTS_MEMORY_FAILURE
d949f36f 462
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463config X86_VISWS
464 bool "SGI 320/540 (Visual Workstation)"
c5c606d9
RT
465 depends on X86_32 && PCI && X86_MPPARSE && PCI_GODIRECT
466 depends on X86_32_NON_STANDARD
467 ---help---
1b84e1c8
IM
468 The SGI Visual Workstation series is an IA32-based workstation
469 based on SGI systems chips with some legacy PC hardware attached.
470
471 Say Y here to create a kernel to run on the SGI 320 or 540.
472
473 A kernel compiled for the Visual Workstation will run on general
474 PCs as well. See <file:Documentation/sgi-visws.txt> for details.
475
9c398017
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476config X86_SUMMIT
477 bool "Summit/EXA (IBM x440)"
e0c7ae37 478 depends on X86_32_NON_STANDARD
8f9ca475 479 ---help---
9c398017
IM
480 This option is needed for IBM systems that use the Summit/EXA chipset.
481 In particular, it is needed for the x440.
1f972768 482
9c398017 483config X86_ES7000
c5c606d9 484 bool "Unisys ES7000 IA32 series"
26f7ef14 485 depends on X86_32_NON_STANDARD && X86_BIGSMP
8f9ca475 486 ---help---
9c398017
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487 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
488 supposed to run on an IA32-based Unisys ES7000 system.
489
ae1e9130 490config SCHED_OMIT_FRAME_POINTER
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491 def_bool y
492 prompt "Single-depth WCHAN output"
a87d0914 493 depends on X86
8f9ca475 494 ---help---
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495 Calculate simpler /proc/<PID>/wchan values. If this option
496 is disabled then wchan values will recurse back to the
497 caller function. This provides more accurate wchan values,
498 at the expense of slightly more scheduling overhead.
499
500 If in doubt, say "Y".
501
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502menuconfig PARAVIRT_GUEST
503 bool "Paravirtualized guest support"
8f9ca475 504 ---help---
506f1d07
SR
505 Say Y here to get to see options related to running Linux under
506 various hypervisors. This option alone does not add any kernel code.
507
508 If you say N, all options in this submenu will be skipped and disabled.
509
510if PARAVIRT_GUEST
511
512source "arch/x86/xen/Kconfig"
513
514config VMI
d0153ca3 515 bool "VMI Guest support (DEPRECATED)"
506f1d07 516 select PARAVIRT
42d545c9 517 depends on X86_32
8f9ca475 518 ---help---
506f1d07
SR
519 VMI provides a paravirtualized interface to the VMware ESX server
520 (it could be used by other hypervisors in theory too, but is not
521 at the moment), by linking the kernel to a GPL-ed ROM module
522 provided by the hypervisor.
523
d0153ca3
AK
524 As of September 2009, VMware has started a phased retirement
525 of this feature from VMware's products. Please see
526 feature-removal-schedule.txt for details. If you are
527 planning to enable this option, please note that you cannot
528 live migrate a VMI enabled VM to a future VMware product,
529 which doesn't support VMI. So if you expect your kernel to
530 seamlessly migrate to newer VMware products, keep this
531 disabled.
532
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533config KVM_CLOCK
534 bool "KVM paravirtualized clock"
535 select PARAVIRT
f6e16d5a 536 select PARAVIRT_CLOCK
8f9ca475 537 ---help---
790c73f6
GOC
538 Turning on this option will allow you to run a paravirtualized clock
539 when running over the KVM hypervisor. Instead of relying on a PIT
540 (or probably other) emulation by the underlying device model, the host
541 provides the guest with timing infrastructure such as time of day, and
542 system time
543
0cf1bfd2
MT
544config KVM_GUEST
545 bool "KVM Guest support"
546 select PARAVIRT
8f9ca475
IM
547 ---help---
548 This option enables various optimizations for running under the KVM
549 hypervisor.
0cf1bfd2 550
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SR
551source "arch/x86/lguest/Kconfig"
552
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553config PARAVIRT
554 bool "Enable paravirtualization code"
8f9ca475 555 ---help---
e61bd94a
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556 This changes the kernel so it can modify itself when it is run
557 under a hypervisor, potentially improving performance significantly
558 over full virtualization. However, when run without a hypervisor
559 the kernel is theoretically slower and slightly larger.
560
b4ecc126
JF
561config PARAVIRT_SPINLOCKS
562 bool "Paravirtualization layer for spinlocks"
563 depends on PARAVIRT && SMP && EXPERIMENTAL
564 ---help---
565 Paravirtualized spinlocks allow a pvops backend to replace the
566 spinlock implementation with something virtualization-friendly
567 (for example, block the virtual CPU rather than spinning).
568
569 Unfortunately the downside is an up to 5% performance hit on
570 native kernels, with various workloads.
571
572 If you are unsure how to answer this question, answer N.
573
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GH
574config PARAVIRT_CLOCK
575 bool
7af192c9 576
506f1d07
SR
577endif
578
97349135 579config PARAVIRT_DEBUG
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IM
580 bool "paravirt-ops debugging"
581 depends on PARAVIRT && DEBUG_KERNEL
582 ---help---
583 Enable to debug paravirt_ops internals. Specifically, BUG if
584 a paravirt_op is missing when it is called.
97349135 585
08677214
YL
586config NO_BOOTMEM
587 default y
588 bool "Disable Bootmem code"
08677214
YL
589 ---help---
590 Use early_res directly instead of bootmem before slab is ready.
591 - allocator (buddy) [generic]
592 - early allocator (bootmem) [generic]
593 - very early allocator (reserve_early*()) [x86]
594 - very very early allocator (early brk model) [x86]
595 So reduce one layer between early allocator to final allocator
596
597
03273184
YL
598config MEMTEST
599 bool "Memtest"
8f9ca475 600 ---help---
c64df707 601 This option adds a kernel parameter 'memtest', which allows memtest
03273184 602 to be set.
8f9ca475
IM
603 memtest=0, mean disabled; -- default
604 memtest=1, mean do 1 test pattern;
605 ...
606 memtest=4, mean do 4 test patterns.
aba3728c 607 If you are unsure how to answer this question, answer N.
506f1d07
SR
608
609config X86_SUMMIT_NUMA
3c2362e6 610 def_bool y
e0c7ae37 611 depends on X86_32 && NUMA && X86_32_NON_STANDARD
506f1d07
SR
612
613config X86_CYCLONE_TIMER
3c2362e6 614 def_bool y
e0c7ae37 615 depends on X86_32_NON_STANDARD
506f1d07 616
506f1d07
SR
617source "arch/x86/Kconfig.cpu"
618
619config HPET_TIMER
3c2362e6 620 def_bool X86_64
506f1d07 621 prompt "HPET Timer Support" if X86_32
8f9ca475
IM
622 ---help---
623 Use the IA-PC HPET (High Precision Event Timer) to manage
624 time in preference to the PIT and RTC, if a HPET is
625 present.
626 HPET is the next generation timer replacing legacy 8254s.
627 The HPET provides a stable time base on SMP
628 systems, unlike the TSC, but it is more expensive to access,
629 as it is off-chip. You can find the HPET spec at
630 <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>.
506f1d07 631
8f9ca475
IM
632 You can safely choose Y here. However, HPET will only be
633 activated if the platform and the BIOS support this feature.
634 Otherwise the 8254 will be used for timing services.
506f1d07 635
8f9ca475 636 Choose N to continue using the legacy 8254 timer.
506f1d07
SR
637
638config HPET_EMULATE_RTC
3c2362e6 639 def_bool y
9d8af78b 640 depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
506f1d07 641
bb24c471
JP
642config APB_TIMER
643 def_bool y if MRST
644 prompt "Langwell APB Timer Support" if X86_MRST
645 help
646 APB timer is the replacement for 8254, HPET on X86 MID platforms.
647 The APBT provides a stable time base on SMP
648 systems, unlike the TSC, but it is more expensive to access,
649 as it is off-chip. APB timers are always running regardless of CPU
650 C states, they are used as per CPU clockevent device when possible.
651
506f1d07
SR
652# Mark as embedded because too many people got it wrong.
653# The code disables itself when not needed.
7ae9392c
TP
654config DMI
655 default y
656 bool "Enable DMI scanning" if EMBEDDED
8f9ca475 657 ---help---
7ae9392c
TP
658 Enabled scanning of DMI to identify machine quirks. Say Y
659 here unless you have verified that your setup is not
660 affected by entries in the DMI blacklist. Required by PNP
661 BIOS code.
662
506f1d07
SR
663config GART_IOMMU
664 bool "GART IOMMU support" if EMBEDDED
665 default y
666 select SWIOTLB
0e152cd7 667 depends on X86_64 && PCI && K8_NB
8f9ca475 668 ---help---
506f1d07
SR
669 Support for full DMA access of devices with 32bit memory access only
670 on systems with more than 3GB. This is usually needed for USB,
671 sound, many IDE/SATA chipsets and some other devices.
672 Provides a driver for the AMD Athlon64/Opteron/Turion/Sempron GART
673 based hardware IOMMU and a software bounce buffer based IOMMU used
674 on Intel systems and as fallback.
675 The code is only active when needed (enough memory and limited
676 device) unless CONFIG_IOMMU_DEBUG or iommu=force is specified
677 too.
678
679config CALGARY_IOMMU
680 bool "IBM Calgary IOMMU support"
681 select SWIOTLB
682 depends on X86_64 && PCI && EXPERIMENTAL
8f9ca475 683 ---help---
506f1d07
SR
684 Support for hardware IOMMUs in IBM's xSeries x366 and x460
685 systems. Needed to run systems with more than 3GB of memory
686 properly with 32-bit PCI devices that do not support DAC
687 (Double Address Cycle). Calgary also supports bus level
688 isolation, where all DMAs pass through the IOMMU. This
689 prevents them from going anywhere except their intended
690 destination. This catches hard-to-find kernel bugs and
691 mis-behaving drivers and devices that do not use the DMA-API
692 properly to set up their DMA buffers. The IOMMU can be
693 turned off at boot time with the iommu=off parameter.
694 Normally the kernel will make the right choice by itself.
695 If unsure, say Y.
696
697config CALGARY_IOMMU_ENABLED_BY_DEFAULT
3c2362e6
HH
698 def_bool y
699 prompt "Should Calgary be enabled by default?"
506f1d07 700 depends on CALGARY_IOMMU
8f9ca475 701 ---help---
506f1d07
SR
702 Should Calgary be enabled by default? if you choose 'y', Calgary
703 will be used (if it exists). If you choose 'n', Calgary will not be
704 used even if it exists. If you choose 'n' and would like to use
705 Calgary anyway, pass 'iommu=calgary' on the kernel command line.
706 If unsure, say Y.
707
2b188723
JR
708config AMD_IOMMU
709 bool "AMD IOMMU support"
07c40e8a 710 select SWIOTLB
a80dc3e0 711 select PCI_MSI
24d2ba0a 712 depends on X86_64 && PCI && ACPI
8f9ca475 713 ---help---
18d22200
JR
714 With this option you can enable support for AMD IOMMU hardware in
715 your system. An IOMMU is a hardware component which provides
716 remapping of DMA memory accesses from devices. With an AMD IOMMU you
717 can isolate the the DMA memory of different devices and protect the
718 system from misbehaving device drivers or hardware.
719
720 You can find out if your system has an AMD IOMMU if you look into
721 your BIOS for an option to enable it or if you have an IVRS ACPI
722 table.
2b188723 723
2e117604
JR
724config AMD_IOMMU_STATS
725 bool "Export AMD IOMMU statistics to debugfs"
726 depends on AMD_IOMMU
727 select DEBUG_FS
8f9ca475 728 ---help---
2e117604
JR
729 This option enables code in the AMD IOMMU driver to collect various
730 statistics about whats happening in the driver and exports that
731 information to userspace via debugfs.
732 If unsure, say N.
733
506f1d07
SR
734# need this always selected by IOMMU for the VIA workaround
735config SWIOTLB
a1afd01c 736 def_bool y if X86_64
8f9ca475 737 ---help---
506f1d07
SR
738 Support for software bounce buffers used on x86-64 systems
739 which don't have a hardware IOMMU (e.g. the current generation
740 of Intel's x86-64 CPUs). Using this PCI devices which can only
741 access 32-bits of memory can be used on systems with more than
742 3 GB of memory. If unsure, say Y.
743
a8522509 744config IOMMU_HELPER
18b743dc 745 def_bool (CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU)
d25e26b6 746
1aaf1183
JR
747config IOMMU_API
748 def_bool (AMD_IOMMU || DMAR)
749
1184dc2f
MT
750config MAXSMP
751 bool "Configure Maximum number of SMP Processors and NUMA Nodes"
36f5101a
MT
752 depends on X86_64 && SMP && DEBUG_KERNEL && EXPERIMENTAL
753 select CPUMASK_OFFSTACK
8f9ca475 754 ---help---
1184dc2f
MT
755 Configure maximum number of CPUS and NUMA Nodes for this architecture.
756 If unsure, say N.
506f1d07
SR
757
758config NR_CPUS
36f5101a 759 int "Maximum number of CPUs" if SMP && !MAXSMP
2a3313f4 760 range 2 8 if SMP && X86_32 && !X86_BIGSMP
36f5101a 761 range 2 512 if SMP && !MAXSMP
78637a97 762 default "1" if !SMP
d25e26b6 763 default "4096" if MAXSMP
78637a97
MT
764 default "32" if SMP && (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000)
765 default "8" if SMP
8f9ca475 766 ---help---
506f1d07 767 This allows you to specify the maximum number of CPUs which this
d25e26b6 768 kernel will support. The maximum supported value is 512 and the
506f1d07
SR
769 minimum value which makes sense is 2.
770
771 This is purely to save memory - each supported CPU adds
772 approximately eight kilobytes to the kernel image.
773
774config SCHED_SMT
775 bool "SMT (Hyperthreading) scheduler support"
b089c12b 776 depends on X86_HT
8f9ca475 777 ---help---
506f1d07
SR
778 SMT scheduler support improves the CPU scheduler's decision making
779 when dealing with Intel Pentium 4 chips with HyperThreading at a
780 cost of slightly increased overhead in some places. If unsure say
781 N here.
782
783config SCHED_MC
3c2362e6
HH
784 def_bool y
785 prompt "Multi-core scheduler support"
b089c12b 786 depends on X86_HT
8f9ca475 787 ---help---
506f1d07
SR
788 Multi-core scheduler support improves the CPU scheduler's decision
789 making when dealing with multi-core CPU chips at a cost of slightly
790 increased overhead in some places. If unsure say N here.
791
792source "kernel/Kconfig.preempt"
793
794config X86_UP_APIC
795 bool "Local APIC support on uniprocessors"
e0c7ae37 796 depends on X86_32 && !SMP && !X86_32_NON_STANDARD
8f9ca475 797 ---help---
506f1d07
SR
798 A local APIC (Advanced Programmable Interrupt Controller) is an
799 integrated interrupt controller in the CPU. If you have a single-CPU
800 system which has a processor with a local APIC, you can say Y here to
801 enable and use it. If you say Y here even though your machine doesn't
802 have a local APIC, then the kernel will still run with no slowdown at
803 all. The local APIC supports CPU-generated self-interrupts (timer,
804 performance counters), and the NMI watchdog which detects hard
805 lockups.
806
807config X86_UP_IOAPIC
808 bool "IO-APIC support on uniprocessors"
809 depends on X86_UP_APIC
8f9ca475 810 ---help---
506f1d07
SR
811 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
812 SMP-capable replacement for PC-style interrupt controllers. Most
813 SMP systems and many recent uniprocessor systems have one.
814
815 If you have a single-CPU system with an IO-APIC, you can say Y here
816 to use it. If you say Y here even though your machine doesn't have
817 an IO-APIC, then the kernel will still run with no slowdown at all.
818
819config X86_LOCAL_APIC
3c2362e6 820 def_bool y
e0c7ae37 821 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
506f1d07
SR
822
823config X86_IO_APIC
3c2362e6 824 def_bool y
e0c7ae37 825 depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC
506f1d07
SR
826
827config X86_VISWS_APIC
3c2362e6 828 def_bool y
506f1d07 829 depends on X86_32 && X86_VISWS
506f1d07 830
41b9eb26
SA
831config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
832 bool "Reroute for broken boot IRQs"
41b9eb26 833 depends on X86_IO_APIC
8f9ca475 834 ---help---
41b9eb26
SA
835 This option enables a workaround that fixes a source of
836 spurious interrupts. This is recommended when threaded
837 interrupt handling is used on systems where the generation of
838 superfluous "boot interrupts" cannot be disabled.
839
840 Some chipsets generate a legacy INTx "boot IRQ" when the IRQ
841 entry in the chipset's IO-APIC is masked (as, e.g. the RT
842 kernel does during interrupt handling). On chipsets where this
843 boot IRQ generation cannot be disabled, this workaround keeps
844 the original IRQ line masked so that only the equivalent "boot
845 IRQ" is delivered to the CPUs. The workaround also tells the
846 kernel to set up the IRQ handler on the boot IRQ line. In this
847 way only one interrupt is delivered to the kernel. Otherwise
848 the spurious second interrupt may cause the kernel to bring
849 down (vital) interrupt lines.
850
851 Only affects "broken" chipsets. Interrupt sharing may be
852 increased on these systems.
853
506f1d07 854config X86_MCE
bab9bc65 855 bool "Machine Check / overheating reporting"
506f1d07 856 ---help---
bab9bc65
AK
857 Machine Check support allows the processor to notify the
858 kernel if it detects a problem (e.g. overheating, data corruption).
506f1d07 859 The action the kernel takes depends on the severity of the problem,
bab9bc65 860 ranging from warning messages to halting the machine.
4efc0670 861
506f1d07 862config X86_MCE_INTEL
3c2362e6
HH
863 def_bool y
864 prompt "Intel MCE features"
c1ebf835 865 depends on X86_MCE && X86_LOCAL_APIC
8f9ca475 866 ---help---
506f1d07
SR
867 Additional support for intel specific MCE features such as
868 the thermal monitor.
869
870config X86_MCE_AMD
3c2362e6
HH
871 def_bool y
872 prompt "AMD MCE features"
c1ebf835 873 depends on X86_MCE && X86_LOCAL_APIC
8f9ca475 874 ---help---
506f1d07
SR
875 Additional support for AMD specific MCE features such as
876 the DRAM Error Threshold.
877
4efc0670 878config X86_ANCIENT_MCE
6fc108a0 879 bool "Support for old Pentium 5 / WinChip machine checks"
c31d9633 880 depends on X86_32 && X86_MCE
cd13adcc
HS
881 ---help---
882 Include support for machine check handling on old Pentium 5 or WinChip
883 systems. These typically need to be enabled explicitely on the command
884 line.
4efc0670 885
b2762686
AK
886config X86_MCE_THRESHOLD
887 depends on X86_MCE_AMD || X86_MCE_INTEL
6fc108a0 888 def_bool y
b2762686 889
ea149b36 890config X86_MCE_INJECT
c1ebf835 891 depends on X86_MCE
ea149b36
AK
892 tristate "Machine check injector support"
893 ---help---
894 Provide support for injecting machine checks for testing purposes.
895 If you don't know what a machine check is and you don't do kernel
896 QA it is safe to say n.
897
4efc0670
AK
898config X86_THERMAL_VECTOR
899 def_bool y
5bb38adc 900 depends on X86_MCE_INTEL
4efc0670 901
506f1d07
SR
902config VM86
903 bool "Enable VM86 support" if EMBEDDED
904 default y
905 depends on X86_32
8f9ca475
IM
906 ---help---
907 This option is required by programs like DOSEMU to run 16-bit legacy
506f1d07 908 code on X86 processors. It also may be needed by software like
8f9ca475
IM
909 XFree86 to initialize some video cards via BIOS. Disabling this
910 option saves about 6k.
506f1d07
SR
911
912config TOSHIBA
913 tristate "Toshiba Laptop support"
914 depends on X86_32
915 ---help---
916 This adds a driver to safely access the System Management Mode of
917 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
918 not work on models with a Phoenix BIOS. The System Management Mode
919 is used to set the BIOS and power saving options on Toshiba portables.
920
921 For information on utilities to make use of this driver see the
922 Toshiba Linux utilities web site at:
923 <http://www.buzzard.org.uk/toshiba/>.
924
925 Say Y if you intend to run this kernel on a Toshiba portable.
926 Say N otherwise.
927
928config I8K
929 tristate "Dell laptop support"
506f1d07
SR
930 ---help---
931 This adds a driver to safely access the System Management Mode
932 of the CPU on the Dell Inspiron 8000. The System Management Mode
933 is used to read cpu temperature and cooling fan status and to
934 control the fans on the I8K portables.
935
936 This driver has been tested only on the Inspiron 8000 but it may
937 also work with other Dell laptops. You can force loading on other
938 models by passing the parameter `force=1' to the module. Use at
939 your own risk.
940
941 For information on utilities to make use of this driver see the
942 I8K Linux utilities web site at:
943 <http://people.debian.org/~dz/i8k/>
944
945 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
946 Say N otherwise.
947
948config X86_REBOOTFIXUPS
9ba16087
JB
949 bool "Enable X86 board specific fixups for reboot"
950 depends on X86_32
506f1d07
SR
951 ---help---
952 This enables chipset and/or board specific fixups to be done
953 in order to get reboot to work correctly. This is only needed on
954 some combinations of hardware and BIOS. The symptom, for which
955 this config is intended, is when reboot ends with a stalled/hung
956 system.
957
958 Currently, the only fixup is for the Geode machines using
5e3a77e9 959 CS5530A and CS5536 chipsets and the RDC R-321x SoC.
506f1d07
SR
960
961 Say Y if you want to enable the fixup. Currently, it's safe to
962 enable this option even if you don't need it.
963 Say N otherwise.
964
965config MICROCODE
8d86f390 966 tristate "/dev/cpu/microcode - microcode support"
506f1d07
SR
967 select FW_LOADER
968 ---help---
969 If you say Y here, you will be able to update the microcode on
80cc9f10
PO
970 certain Intel and AMD processors. The Intel support is for the
971 IA32 family, e.g. Pentium Pro, Pentium II, Pentium III,
972 Pentium 4, Xeon etc. The AMD support is for family 0x10 and
973 0x11 processors, e.g. Opteron, Phenom and Turion 64 Ultra.
974 You will obviously need the actual microcode binary data itself
975 which is not shipped with the Linux kernel.
506f1d07 976
8d86f390
PO
977 This option selects the general module only, you need to select
978 at least one vendor specific module as well.
506f1d07
SR
979
980 To compile this driver as a module, choose M here: the
981 module will be called microcode.
982
8d86f390 983config MICROCODE_INTEL
8f9ca475
IM
984 bool "Intel microcode patch loading support"
985 depends on MICROCODE
986 default MICROCODE
987 select FW_LOADER
988 ---help---
989 This options enables microcode patch loading support for Intel
990 processors.
991
992 For latest news and information on obtaining all the required
993 Intel ingredients for this driver, check:
994 <http://www.urbanmyth.org/microcode/>.
8d86f390 995
80cc9f10 996config MICROCODE_AMD
8f9ca475
IM
997 bool "AMD microcode patch loading support"
998 depends on MICROCODE
999 select FW_LOADER
1000 ---help---
1001 If you select this option, microcode patch loading support for AMD
1002 processors will be enabled.
80cc9f10 1003
8f9ca475 1004config MICROCODE_OLD_INTERFACE
3c2362e6 1005 def_bool y
506f1d07 1006 depends on MICROCODE
506f1d07
SR
1007
1008config X86_MSR
1009 tristate "/dev/cpu/*/msr - Model-specific register support"
8f9ca475 1010 ---help---
506f1d07
SR
1011 This device gives privileged processes access to the x86
1012 Model-Specific Registers (MSRs). It is a character device with
1013 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
1014 MSR accesses are directed to a specific CPU on multi-processor
1015 systems.
1016
1017config X86_CPUID
1018 tristate "/dev/cpu/*/cpuid - CPU information support"
8f9ca475 1019 ---help---
506f1d07
SR
1020 This device gives processes access to the x86 CPUID instruction to
1021 be executed on a specific processor. It is a character device
1022 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
1023 /dev/cpu/31/cpuid.
1024
1025choice
1026 prompt "High Memory Support"
506f1d07 1027 default HIGHMEM64G if X86_NUMAQ
6fc108a0 1028 default HIGHMEM4G
506f1d07
SR
1029 depends on X86_32
1030
1031config NOHIGHMEM
1032 bool "off"
1033 depends on !X86_NUMAQ
1034 ---help---
1035 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
1036 However, the address space of 32-bit x86 processors is only 4
1037 Gigabytes large. That means that, if you have a large amount of
1038 physical memory, not all of it can be "permanently mapped" by the
1039 kernel. The physical memory that's not permanently mapped is called
1040 "high memory".
1041
1042 If you are compiling a kernel which will never run on a machine with
1043 more than 1 Gigabyte total physical RAM, answer "off" here (default
1044 choice and suitable for most users). This will result in a "3GB/1GB"
1045 split: 3GB are mapped so that each process sees a 3GB virtual memory
1046 space and the remaining part of the 4GB virtual memory space is used
1047 by the kernel to permanently map as much physical memory as
1048 possible.
1049
1050 If the machine has between 1 and 4 Gigabytes physical RAM, then
1051 answer "4GB" here.
1052
1053 If more than 4 Gigabytes is used then answer "64GB" here. This
1054 selection turns Intel PAE (Physical Address Extension) mode on.
1055 PAE implements 3-level paging on IA32 processors. PAE is fully
1056 supported by Linux, PAE mode is implemented on all recent Intel
1057 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
1058 then the kernel will not boot on CPUs that don't support PAE!
1059
1060 The actual amount of total physical memory will either be
1061 auto detected or can be forced by using a kernel command line option
1062 such as "mem=256M". (Try "man bootparam" or see the documentation of
1063 your boot loader (lilo or loadlin) about how to pass options to the
1064 kernel at boot time.)
1065
1066 If unsure, say "off".
1067
1068config HIGHMEM4G
1069 bool "4GB"
1070 depends on !X86_NUMAQ
8f9ca475 1071 ---help---
506f1d07
SR
1072 Select this if you have a 32-bit processor and between 1 and 4
1073 gigabytes of physical RAM.
1074
1075config HIGHMEM64G
1076 bool "64GB"
1077 depends on !M386 && !M486
1078 select X86_PAE
8f9ca475 1079 ---help---
506f1d07
SR
1080 Select this if you have a 32-bit processor and more than 4
1081 gigabytes of physical RAM.
1082
1083endchoice
1084
1085choice
1086 depends on EXPERIMENTAL
1087 prompt "Memory split" if EMBEDDED
1088 default VMSPLIT_3G
1089 depends on X86_32
8f9ca475 1090 ---help---
506f1d07
SR
1091 Select the desired split between kernel and user memory.
1092
1093 If the address range available to the kernel is less than the
1094 physical memory installed, the remaining memory will be available
1095 as "high memory". Accessing high memory is a little more costly
1096 than low memory, as it needs to be mapped into the kernel first.
1097 Note that increasing the kernel address space limits the range
1098 available to user programs, making the address space there
1099 tighter. Selecting anything other than the default 3G/1G split
1100 will also likely make your kernel incompatible with binary-only
1101 kernel modules.
1102
1103 If you are not absolutely sure what you are doing, leave this
1104 option alone!
1105
1106 config VMSPLIT_3G
1107 bool "3G/1G user/kernel split"
1108 config VMSPLIT_3G_OPT
1109 depends on !X86_PAE
1110 bool "3G/1G user/kernel split (for full 1G low memory)"
1111 config VMSPLIT_2G
1112 bool "2G/2G user/kernel split"
1113 config VMSPLIT_2G_OPT
1114 depends on !X86_PAE
1115 bool "2G/2G user/kernel split (for full 2G low memory)"
1116 config VMSPLIT_1G
1117 bool "1G/3G user/kernel split"
1118endchoice
1119
1120config PAGE_OFFSET
1121 hex
1122 default 0xB0000000 if VMSPLIT_3G_OPT
1123 default 0x80000000 if VMSPLIT_2G
1124 default 0x78000000 if VMSPLIT_2G_OPT
1125 default 0x40000000 if VMSPLIT_1G
1126 default 0xC0000000
1127 depends on X86_32
1128
1129config HIGHMEM
3c2362e6 1130 def_bool y
506f1d07 1131 depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
506f1d07
SR
1132
1133config X86_PAE
9ba16087 1134 bool "PAE (Physical Address Extension) Support"
506f1d07 1135 depends on X86_32 && !HIGHMEM4G
8f9ca475 1136 ---help---
506f1d07
SR
1137 PAE is required for NX support, and furthermore enables
1138 larger swapspace support for non-overcommit purposes. It
1139 has the cost of more pagetable lookup overhead, and also
1140 consumes more pagetable space per process.
1141
600715dc 1142config ARCH_PHYS_ADDR_T_64BIT
8f9ca475 1143 def_bool X86_64 || X86_PAE
600715dc 1144
9e899816
NP
1145config DIRECT_GBPAGES
1146 bool "Enable 1GB pages for kernel pagetables" if EMBEDDED
1147 default y
1148 depends on X86_64
8f9ca475 1149 ---help---
9e899816
NP
1150 Allow the kernel linear mapping to use 1GB pages on CPUs that
1151 support it. This can improve the kernel's performance a tiny bit by
1152 reducing TLB pressure. If in doubt, say "Y".
1153
506f1d07
SR
1154# Common NUMA Features
1155config NUMA
fd51b2d7 1156 bool "Numa Memory Allocation and Scheduler Support"
506f1d07 1157 depends on SMP
604d2055 1158 depends on X86_64 || (X86_32 && HIGHMEM64G && (X86_NUMAQ || X86_BIGSMP || X86_SUMMIT && ACPI) && EXPERIMENTAL)
0699eae1 1159 default y if (X86_NUMAQ || X86_SUMMIT || X86_BIGSMP)
8f9ca475 1160 ---help---
506f1d07 1161 Enable NUMA (Non Uniform Memory Access) support.
fd51b2d7 1162
506f1d07
SR
1163 The kernel will try to allocate memory used by a CPU on the
1164 local memory controller of the CPU and add some more
1165 NUMA awareness to the kernel.
1166
c280ea5e 1167 For 64-bit this is recommended if the system is Intel Core i7
fd51b2d7
KM
1168 (or later), AMD Opteron, or EM64T NUMA.
1169
1170 For 32-bit this is only needed on (rare) 32-bit-only platforms
1171 that support NUMA topologies, such as NUMAQ / Summit, or if you
1172 boot a 32-bit kernel on a 64-bit NUMA platform.
1173
1174 Otherwise, you should say N.
506f1d07
SR
1175
1176comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
1177 depends on X86_32 && X86_SUMMIT && (!HIGHMEM64G || !ACPI)
1178
1179config K8_NUMA
3c2362e6
HH
1180 def_bool y
1181 prompt "Old style AMD Opteron NUMA detection"
1182 depends on X86_64 && NUMA && PCI
8f9ca475
IM
1183 ---help---
1184 Enable K8 NUMA node topology detection. You should say Y here if
1185 you have a multi processor AMD K8 system. This uses an old
1186 method to read the NUMA configuration directly from the builtin
1187 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
1188 instead, which also takes priority if both are compiled in.
506f1d07
SR
1189
1190config X86_64_ACPI_NUMA
3c2362e6
HH
1191 def_bool y
1192 prompt "ACPI NUMA detection"
506f1d07
SR
1193 depends on X86_64 && NUMA && ACPI && PCI
1194 select ACPI_NUMA
8f9ca475 1195 ---help---
506f1d07
SR
1196 Enable ACPI SRAT based node topology detection.
1197
6ec6e0d9
SS
1198# Some NUMA nodes have memory ranges that span
1199# other nodes. Even though a pfn is valid and
1200# between a node's start and end pfns, it may not
1201# reside on that node. See memmap_init_zone()
1202# for details.
1203config NODES_SPAN_OTHER_NODES
1204 def_bool y
1205 depends on X86_64_ACPI_NUMA
1206
506f1d07
SR
1207config NUMA_EMU
1208 bool "NUMA emulation"
1209 depends on X86_64 && NUMA
8f9ca475 1210 ---help---
506f1d07
SR
1211 Enable NUMA emulation. A flat machine will be split
1212 into virtual nodes when booted with "numa=fake=N", where N is the
1213 number of nodes. This is only useful for debugging.
1214
1215config NODES_SHIFT
d25e26b6 1216 int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
51591e31
DR
1217 range 1 10
1218 default "10" if MAXSMP
506f1d07
SR
1219 default "6" if X86_64
1220 default "4" if X86_NUMAQ
1221 default "3"
1222 depends on NEED_MULTIPLE_NODES
8f9ca475 1223 ---help---
1184dc2f 1224 Specify the maximum number of NUMA Nodes available on the target
692105b8 1225 system. Increases memory reserved to accommodate various tables.
506f1d07 1226
c1329375 1227config HAVE_ARCH_BOOTMEM
3c2362e6 1228 def_bool y
506f1d07 1229 depends on X86_32 && NUMA
506f1d07
SR
1230
1231config ARCH_HAVE_MEMORY_PRESENT
3c2362e6 1232 def_bool y
506f1d07 1233 depends on X86_32 && DISCONTIGMEM
506f1d07
SR
1234
1235config NEED_NODE_MEMMAP_SIZE
3c2362e6 1236 def_bool y
506f1d07 1237 depends on X86_32 && (DISCONTIGMEM || SPARSEMEM)
506f1d07
SR
1238
1239config HAVE_ARCH_ALLOC_REMAP
3c2362e6 1240 def_bool y
506f1d07 1241 depends on X86_32 && NUMA
506f1d07
SR
1242
1243config ARCH_FLATMEM_ENABLE
1244 def_bool y
99809963 1245 depends on X86_32 && ARCH_SELECT_MEMORY_MODEL && !NUMA
506f1d07
SR
1246
1247config ARCH_DISCONTIGMEM_ENABLE
1248 def_bool y
b263295d 1249 depends on NUMA && X86_32
506f1d07
SR
1250
1251config ARCH_DISCONTIGMEM_DEFAULT
1252 def_bool y
b263295d
CL
1253 depends on NUMA && X86_32
1254
9492587c
KH
1255config ARCH_PROC_KCORE_TEXT
1256 def_bool y
1257 depends on X86_64 && PROC_KCORE
1258
b263295d
CL
1259config ARCH_SPARSEMEM_DEFAULT
1260 def_bool y
1261 depends on X86_64
506f1d07
SR
1262
1263config ARCH_SPARSEMEM_ENABLE
1264 def_bool y
4272ebfb 1265 depends on X86_64 || NUMA || (EXPERIMENTAL && X86_32) || X86_32_NON_STANDARD
506f1d07
SR
1266 select SPARSEMEM_STATIC if X86_32
1267 select SPARSEMEM_VMEMMAP_ENABLE if X86_64
1268
1269config ARCH_SELECT_MEMORY_MODEL
1270 def_bool y
b263295d 1271 depends on ARCH_SPARSEMEM_ENABLE
506f1d07
SR
1272
1273config ARCH_MEMORY_PROBE
1274 def_bool X86_64
1275 depends on MEMORY_HOTPLUG
1276
a29815a3
AK
1277config ILLEGAL_POINTER_VALUE
1278 hex
1279 default 0 if X86_32
1280 default 0xdead000000000000 if X86_64
1281
506f1d07
SR
1282source "mm/Kconfig"
1283
1284config HIGHPTE
1285 bool "Allocate 3rd-level pagetables from highmem"
6fc108a0 1286 depends on HIGHMEM
8f9ca475 1287 ---help---
506f1d07
SR
1288 The VM uses one page table entry for each page of physical memory.
1289 For systems with a lot of RAM, this can be wasteful of precious
1290 low memory. Setting this option will put user-space page table
1291 entries in high memory.
1292
9f077871 1293config X86_CHECK_BIOS_CORRUPTION
8f9ca475
IM
1294 bool "Check for low memory corruption"
1295 ---help---
1296 Periodically check for memory corruption in low memory, which
1297 is suspected to be caused by BIOS. Even when enabled in the
1298 configuration, it is disabled at runtime. Enable it by
1299 setting "memory_corruption_check=1" on the kernel command
1300 line. By default it scans the low 64k of memory every 60
1301 seconds; see the memory_corruption_check_size and
1302 memory_corruption_check_period parameters in
1303 Documentation/kernel-parameters.txt to adjust this.
1304
1305 When enabled with the default parameters, this option has
1306 almost no overhead, as it reserves a relatively small amount
1307 of memory and scans it infrequently. It both detects corruption
1308 and prevents it from affecting the running system.
1309
1310 It is, however, intended as a diagnostic tool; if repeatable
1311 BIOS-originated corruption always affects the same memory,
1312 you can use memmap= to prevent the kernel from using that
1313 memory.
9f077871 1314
c885df50 1315config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
8f9ca475 1316 bool "Set the default setting of memory_corruption_check"
c885df50
JF
1317 depends on X86_CHECK_BIOS_CORRUPTION
1318 default y
8f9ca475
IM
1319 ---help---
1320 Set whether the default state of memory_corruption_check is
1321 on or off.
c885df50 1322
fc381519 1323config X86_RESERVE_LOW_64K
8f9ca475 1324 bool "Reserve low 64K of RAM on AMI/Phoenix BIOSen"
fc381519 1325 default y
8f9ca475
IM
1326 ---help---
1327 Reserve the first 64K of physical RAM on BIOSes that are known
1328 to potentially corrupt that memory range. A numbers of BIOSes are
1329 known to utilize this area during suspend/resume, so it must not
1330 be used by the kernel.
fc381519 1331
8f9ca475
IM
1332 Set this to N if you are absolutely sure that you trust the BIOS
1333 to get all its memory reservations and usages right.
fc381519 1334
8f9ca475
IM
1335 If you have doubts about the BIOS (e.g. suspend/resume does not
1336 work or there's kernel crashes after certain hardware hotplug
1337 events) and it's not AMI or Phoenix, then you might want to enable
1338 X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check typical
1339 corruption patterns.
fc381519 1340
8f9ca475 1341 Say Y if unsure.
fc381519 1342
506f1d07
SR
1343config MATH_EMULATION
1344 bool
1345 prompt "Math emulation" if X86_32
1346 ---help---
1347 Linux can emulate a math coprocessor (used for floating point
1348 operations) if you don't have one. 486DX and Pentium processors have
1349 a math coprocessor built in, 486SX and 386 do not, unless you added
1350 a 487DX or 387, respectively. (The messages during boot time can
1351 give you some hints here ["man dmesg"].) Everyone needs either a
1352 coprocessor or this emulation.
1353
1354 If you don't have a math coprocessor, you need to say Y here; if you
1355 say Y here even though you have a coprocessor, the coprocessor will
1356 be used nevertheless. (This behavior can be changed with the kernel
1357 command line option "no387", which comes handy if your coprocessor
1358 is broken. Try "man bootparam" or see the documentation of your boot
1359 loader (lilo or loadlin) about how to pass options to the kernel at
1360 boot time.) This means that it is a good idea to say Y here if you
1361 intend to use this kernel on different machines.
1362
1363 More information about the internals of the Linux math coprocessor
1364 emulation can be found in <file:arch/x86/math-emu/README>.
1365
1366 If you are not sure, say Y; apart from resulting in a 66 KB bigger
1367 kernel, it won't hurt.
1368
1369config MTRR
6fc108a0 1370 def_bool y
c03cb314 1371 prompt "MTRR (Memory Type Range Register) support" if EMBEDDED
506f1d07
SR
1372 ---help---
1373 On Intel P6 family processors (Pentium Pro, Pentium II and later)
1374 the Memory Type Range Registers (MTRRs) may be used to control
1375 processor access to memory ranges. This is most useful if you have
1376 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
1377 allows bus write transfers to be combined into a larger transfer
1378 before bursting over the PCI/AGP bus. This can increase performance
1379 of image write operations 2.5 times or more. Saying Y here creates a
1380 /proc/mtrr file which may be used to manipulate your processor's
1381 MTRRs. Typically the X server should use this.
1382
1383 This code has a reasonably generic interface so that similar
1384 control registers on other processors can be easily supported
1385 as well:
1386
1387 The Cyrix 6x86, 6x86MX and M II processors have Address Range
1388 Registers (ARRs) which provide a similar functionality to MTRRs. For
1389 these, the ARRs are used to emulate the MTRRs.
1390 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
1391 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
1392 write-combining. All of these processors are supported by this code
1393 and it makes sense to say Y here if you have one of them.
1394
1395 Saying Y here also fixes a problem with buggy SMP BIOSes which only
1396 set the MTRRs for the boot CPU and not for the secondary CPUs. This
1397 can lead to all sorts of problems, so it's good to say Y here.
1398
1399 You can safely say Y even if your machine doesn't have MTRRs, you'll
1400 just add about 9 KB to your kernel.
1401
7225e751 1402 See <file:Documentation/x86/mtrr.txt> for more information.
506f1d07 1403
95ffa243 1404config MTRR_SANITIZER
2ffb3501 1405 def_bool y
95ffa243
YL
1406 prompt "MTRR cleanup support"
1407 depends on MTRR
8f9ca475 1408 ---help---
aba3728c
TG
1409 Convert MTRR layout from continuous to discrete, so X drivers can
1410 add writeback entries.
95ffa243 1411
aba3728c 1412 Can be disabled with disable_mtrr_cleanup on the kernel command line.
692105b8 1413 The largest mtrr entry size for a continuous block can be set with
aba3728c 1414 mtrr_chunk_size.
95ffa243 1415
2ffb3501 1416 If unsure, say Y.
95ffa243
YL
1417
1418config MTRR_SANITIZER_ENABLE_DEFAULT
f5098d62
YL
1419 int "MTRR cleanup enable value (0-1)"
1420 range 0 1
1421 default "0"
95ffa243 1422 depends on MTRR_SANITIZER
8f9ca475 1423 ---help---
f5098d62 1424 Enable mtrr cleanup default value
95ffa243 1425
12031a62
YL
1426config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
1427 int "MTRR cleanup spare reg num (0-7)"
1428 range 0 7
1429 default "1"
1430 depends on MTRR_SANITIZER
8f9ca475 1431 ---help---
12031a62 1432 mtrr cleanup spare entries default, it can be changed via
aba3728c 1433 mtrr_spare_reg_nr=N on the kernel command line.
12031a62 1434
2e5d9c85 1435config X86_PAT
6fc108a0 1436 def_bool y
c03cb314 1437 prompt "x86 PAT support" if EMBEDDED
2a8a2719 1438 depends on MTRR
8f9ca475 1439 ---help---
2e5d9c85 1440 Use PAT attributes to setup page level cache control.
042b78e4 1441
2e5d9c85 1442 PATs are the modern equivalents of MTRRs and are much more
1443 flexible than MTRRs.
1444
1445 Say N here if you see bootup problems (boot crash, boot hang,
042b78e4 1446 spontaneous reboots) or a non-working video driver.
2e5d9c85 1447
1448 If unsure, say Y.
1449
46cf98cd
VP
1450config ARCH_USES_PG_UNCACHED
1451 def_bool y
1452 depends on X86_PAT
1453
506f1d07 1454config EFI
9ba16087 1455 bool "EFI runtime service support"
5b83683f 1456 depends on ACPI
506f1d07 1457 ---help---
8f9ca475
IM
1458 This enables the kernel to use EFI runtime services that are
1459 available (such as the EFI variable services).
506f1d07 1460
8f9ca475
IM
1461 This option is only useful on systems that have EFI firmware.
1462 In addition, you should use the latest ELILO loader available
1463 at <http://elilo.sourceforge.net> in order to take advantage
1464 of EFI runtime services. However, even with this option, the
1465 resultant kernel should continue to boot on existing non-EFI
1466 platforms.
506f1d07 1467
506f1d07 1468config SECCOMP
3c2362e6
HH
1469 def_bool y
1470 prompt "Enable seccomp to safely compute untrusted bytecode"
8f9ca475 1471 ---help---
506f1d07
SR
1472 This kernel feature is useful for number crunching applications
1473 that may need to compute untrusted bytecode during their
1474 execution. By using pipes or other transports made available to
1475 the process as file descriptors supporting the read/write
1476 syscalls, it's possible to isolate those applications in
1477 their own address space using seccomp. Once seccomp is
9c0bbee8 1478 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
506f1d07
SR
1479 and the task is only allowed to execute a few safe syscalls
1480 defined by each seccomp mode.
1481
1482 If unsure, say Y. Only embedded should say N here.
1483
1484config CC_STACKPROTECTOR
1485 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
8f9ca475
IM
1486 ---help---
1487 This option turns on the -fstack-protector GCC feature. This
113c5413
IM
1488 feature puts, at the beginning of functions, a canary value on
1489 the stack just before the return address, and validates
506f1d07
SR
1490 the value just before actually returning. Stack based buffer
1491 overflows (that need to overwrite this return address) now also
1492 overwrite the canary, which gets detected and the attack is then
1493 neutralized via a kernel panic.
1494
1495 This feature requires gcc version 4.2 or above, or a distribution
1496 gcc with the feature backported. Older versions are automatically
113c5413
IM
1497 detected and for those versions, this configuration option is
1498 ignored. (and a warning is printed during bootup)
506f1d07
SR
1499
1500source kernel/Kconfig.hz
1501
1502config KEXEC
1503 bool "kexec system call"
8f9ca475 1504 ---help---
506f1d07
SR
1505 kexec is a system call that implements the ability to shutdown your
1506 current kernel, and to start another kernel. It is like a reboot
1507 but it is independent of the system firmware. And like a reboot
1508 you can start any kernel with it, not just Linux.
1509
1510 The name comes from the similarity to the exec system call.
1511
1512 It is an ongoing process to be certain the hardware in a machine
1513 is properly shutdown, so do not be surprised if this code does not
1514 initially work for you. It may help to enable device hotplugging
1515 support. As of this writing the exact hardware interface is
1516 strongly in flux, so no good recommendation can be made.
1517
1518config CRASH_DUMP
04b69447 1519 bool "kernel crash dumps"
506f1d07 1520 depends on X86_64 || (X86_32 && HIGHMEM)
8f9ca475 1521 ---help---
506f1d07
SR
1522 Generate crash dump after being started by kexec.
1523 This should be normally only set in special crash dump kernels
1524 which are loaded in the main kernel with kexec-tools into
1525 a specially reserved region and then later executed after
1526 a crash by kdump/kexec. The crash dump kernel must be compiled
1527 to a memory address not used by the main kernel or BIOS using
1528 PHYSICAL_START, or it must be built as a relocatable image
1529 (CONFIG_RELOCATABLE=y).
1530 For more details see Documentation/kdump/kdump.txt
1531
3ab83521
HY
1532config KEXEC_JUMP
1533 bool "kexec jump (EXPERIMENTAL)"
1534 depends on EXPERIMENTAL
fee7b0d8 1535 depends on KEXEC && HIBERNATION
8f9ca475 1536 ---help---
89081d17
HY
1537 Jump between original kernel and kexeced kernel and invoke
1538 code in physical address mode via KEXEC
3ab83521 1539
506f1d07
SR
1540config PHYSICAL_START
1541 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
ceefccc9 1542 default "0x1000000"
8f9ca475 1543 ---help---
506f1d07
SR
1544 This gives the physical address where the kernel is loaded.
1545
1546 If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then
1547 bzImage will decompress itself to above physical address and
1548 run from there. Otherwise, bzImage will run from the address where
1549 it has been loaded by the boot loader and will ignore above physical
1550 address.
1551
1552 In normal kdump cases one does not have to set/change this option
1553 as now bzImage can be compiled as a completely relocatable image
1554 (CONFIG_RELOCATABLE=y) and be used to load and run from a different
1555 address. This option is mainly useful for the folks who don't want
1556 to use a bzImage for capturing the crash dump and want to use a
1557 vmlinux instead. vmlinux is not relocatable hence a kernel needs
1558 to be specifically compiled to run from a specific memory area
1559 (normally a reserved region) and this option comes handy.
1560
ceefccc9
PA
1561 So if you are using bzImage for capturing the crash dump,
1562 leave the value here unchanged to 0x1000000 and set
1563 CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux
1564 for capturing the crash dump change this value to start of
1565 the reserved region. In other words, it can be set based on
1566 the "X" value as specified in the "crashkernel=YM@XM"
1567 command line boot parameter passed to the panic-ed
1568 kernel. Please take a look at Documentation/kdump/kdump.txt
1569 for more details about crash dumps.
506f1d07
SR
1570
1571 Usage of bzImage for capturing the crash dump is recommended as
1572 one does not have to build two kernels. Same kernel can be used
1573 as production kernel and capture kernel. Above option should have
1574 gone away after relocatable bzImage support is introduced. But it
1575 is present because there are users out there who continue to use
1576 vmlinux for dump capture. This option should go away down the
1577 line.
1578
1579 Don't change this unless you know what you are doing.
1580
1581config RELOCATABLE
26717808
PA
1582 bool "Build a relocatable kernel"
1583 default y
8f9ca475 1584 ---help---
506f1d07
SR
1585 This builds a kernel image that retains relocation information
1586 so it can be loaded someplace besides the default 1MB.
1587 The relocations tend to make the kernel binary about 10% larger,
1588 but are discarded at runtime.
1589
1590 One use is for the kexec on panic case where the recovery kernel
1591 must live at a different physical address than the primary
1592 kernel.
1593
1594 Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address
1595 it has been loaded at and the compile time physical address
1596 (CONFIG_PHYSICAL_START) is ignored.
1597
845adf72
PA
1598# Relocation on x86-32 needs some additional build support
1599config X86_NEED_RELOCS
1600 def_bool y
1601 depends on X86_32 && RELOCATABLE
1602
506f1d07 1603config PHYSICAL_ALIGN
6fc108a0 1604 hex "Alignment value to which kernel should be aligned" if X86_32
ceefccc9
PA
1605 default "0x1000000"
1606 range 0x2000 0x1000000
8f9ca475 1607 ---help---
506f1d07
SR
1608 This value puts the alignment restrictions on physical address
1609 where kernel is loaded and run from. Kernel is compiled for an
1610 address which meets above alignment restriction.
1611
1612 If bootloader loads the kernel at a non-aligned address and
1613 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
1614 address aligned to above value and run from there.
1615
1616 If bootloader loads the kernel at a non-aligned address and
1617 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
1618 load address and decompress itself to the address it has been
1619 compiled for and run from there. The address for which kernel is
1620 compiled already meets above alignment restrictions. Hence the
1621 end result is that kernel runs from a physical address meeting
1622 above alignment restrictions.
1623
1624 Don't change this unless you know what you are doing.
1625
1626config HOTPLUG_CPU
7c13e6a3 1627 bool "Support for hot-pluggable CPUs"
4b19ed91 1628 depends on SMP && HOTPLUG
506f1d07 1629 ---help---
7c13e6a3
DS
1630 Say Y here to allow turning CPUs off and on. CPUs can be
1631 controlled through /sys/devices/system/cpu.
1632 ( Note: power management support will enable this option
1633 automatically on SMP systems. )
1634 Say N if you want to disable CPU hotplug.
506f1d07
SR
1635
1636config COMPAT_VDSO
3c2362e6
HH
1637 def_bool y
1638 prompt "Compat VDSO support"
af65d648 1639 depends on X86_32 || IA32_EMULATION
8f9ca475 1640 ---help---
af65d648 1641 Map the 32-bit VDSO to the predictable old-style address too.
e84446de 1642
506f1d07
SR
1643 Say N here if you are running a sufficiently recent glibc
1644 version (2.3.3 or later), to remove the high-mapped
1645 VDSO mapping and to exclusively use the randomized VDSO.
1646
1647 If unsure, say Y.
1648
516cbf37
TB
1649config CMDLINE_BOOL
1650 bool "Built-in kernel command line"
8f9ca475 1651 ---help---
516cbf37
TB
1652 Allow for specifying boot arguments to the kernel at
1653 build time. On some systems (e.g. embedded ones), it is
1654 necessary or convenient to provide some or all of the
1655 kernel boot arguments with the kernel itself (that is,
1656 to not rely on the boot loader to provide them.)
1657
1658 To compile command line arguments into the kernel,
1659 set this option to 'Y', then fill in the
1660 the boot arguments in CONFIG_CMDLINE.
1661
1662 Systems with fully functional boot loaders (i.e. non-embedded)
1663 should leave this option set to 'N'.
1664
1665config CMDLINE
1666 string "Built-in kernel command string"
1667 depends on CMDLINE_BOOL
1668 default ""
8f9ca475 1669 ---help---
516cbf37
TB
1670 Enter arguments here that should be compiled into the kernel
1671 image and used at boot time. If the boot loader provides a
1672 command line at boot time, it is appended to this string to
1673 form the full kernel command line, when the system boots.
1674
1675 However, you can use the CONFIG_CMDLINE_OVERRIDE option to
1676 change this behavior.
1677
1678 In most cases, the command line (whether built-in or provided
1679 by the boot loader) should specify the device for the root
1680 file system.
1681
1682config CMDLINE_OVERRIDE
1683 bool "Built-in command line overrides boot loader arguments"
516cbf37 1684 depends on CMDLINE_BOOL
8f9ca475 1685 ---help---
516cbf37
TB
1686 Set this option to 'Y' to have the kernel ignore the boot loader
1687 command line, and use ONLY the built-in command line.
1688
1689 This is used to work around broken boot loaders. This should
1690 be set to 'N' under normal conditions.
1691
506f1d07
SR
1692endmenu
1693
1694config ARCH_ENABLE_MEMORY_HOTPLUG
1695 def_bool y
1696 depends on X86_64 || (X86_32 && HIGHMEM)
1697
35551053
GH
1698config ARCH_ENABLE_MEMORY_HOTREMOVE
1699 def_bool y
1700 depends on MEMORY_HOTPLUG
1701
506f1d07
SR
1702config HAVE_ARCH_EARLY_PFN_TO_NID
1703 def_bool X86_64
1704 depends on NUMA
1705
e534c7c5
LS
1706config USE_PERCPU_NUMA_NODE_ID
1707 def_bool X86_64
1708 depends on NUMA
1709
da85f865 1710menu "Power management and ACPI options"
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SR
1711
1712config ARCH_HIBERNATION_HEADER
3c2362e6 1713 def_bool y
e279b6c1 1714 depends on X86_64 && HIBERNATION
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SR
1715
1716source "kernel/power/Kconfig"
1717
1718source "drivers/acpi/Kconfig"
1719
efafc8b2
FT
1720source "drivers/sfi/Kconfig"
1721
a6b68076 1722config X86_APM_BOOT
6fc108a0 1723 def_bool y
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1724 depends on APM || APM_MODULE
1725
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SR
1726menuconfig APM
1727 tristate "APM (Advanced Power Management) BIOS support"
efefa6f6 1728 depends on X86_32 && PM_SLEEP
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SR
1729 ---help---
1730 APM is a BIOS specification for saving power using several different
1731 techniques. This is mostly useful for battery powered laptops with
1732 APM compliant BIOSes. If you say Y here, the system time will be
1733 reset after a RESUME operation, the /proc/apm device will provide
1734 battery status information, and user-space programs will receive
1735 notification of APM "events" (e.g. battery status change).
1736
1737 If you select "Y" here, you can disable actual use of the APM
1738 BIOS by passing the "apm=off" option to the kernel at boot time.
1739
1740 Note that the APM support is almost completely disabled for
1741 machines with more than one CPU.
1742
1743 In order to use APM, you will need supporting software. For location
53471121 1744 and more information, read <file:Documentation/power/pm.txt> and the
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SR
1745 Battery Powered Linux mini-HOWTO, available from
1746 <http://www.tldp.org/docs.html#howto>.
1747
1748 This driver does not spin down disk drives (see the hdparm(8)
1749 manpage ("man 8 hdparm") for that), and it doesn't turn off
1750 VESA-compliant "green" monitors.
1751
1752 This driver does not support the TI 4000M TravelMate and the ACER
1753 486/DX4/75 because they don't have compliant BIOSes. Many "green"
1754 desktop machines also don't have compliant BIOSes, and this driver
1755 may cause those machines to panic during the boot phase.
1756
1757 Generally, if you don't have a battery in your machine, there isn't
1758 much point in using this driver and you should say N. If you get
1759 random kernel OOPSes or reboots that don't seem to be related to
1760 anything, try disabling/enabling this option (or disabling/enabling
1761 APM in your BIOS).
1762
1763 Some other things you should try when experiencing seemingly random,
1764 "weird" problems:
1765
1766 1) make sure that you have enough swap space and that it is
1767 enabled.
1768 2) pass the "no-hlt" option to the kernel
1769 3) switch on floating point emulation in the kernel and pass
1770 the "no387" option to the kernel
1771 4) pass the "floppy=nodma" option to the kernel
1772 5) pass the "mem=4M" option to the kernel (thereby disabling
1773 all but the first 4 MB of RAM)
1774 6) make sure that the CPU is not over clocked.
1775 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
1776 8) disable the cache from your BIOS settings
1777 9) install a fan for the video card or exchange video RAM
1778 10) install a better fan for the CPU
1779 11) exchange RAM chips
1780 12) exchange the motherboard.
1781
1782 To compile this driver as a module, choose M here: the
1783 module will be called apm.
1784
1785if APM
1786
1787config APM_IGNORE_USER_SUSPEND
1788 bool "Ignore USER SUSPEND"
8f9ca475 1789 ---help---
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SR
1790 This option will ignore USER SUSPEND requests. On machines with a
1791 compliant APM BIOS, you want to say N. However, on the NEC Versa M
1792 series notebooks, it is necessary to say Y because of a BIOS bug.
1793
1794config APM_DO_ENABLE
1795 bool "Enable PM at boot time"
1796 ---help---
1797 Enable APM features at boot time. From page 36 of the APM BIOS
1798 specification: "When disabled, the APM BIOS does not automatically
1799 power manage devices, enter the Standby State, enter the Suspend
1800 State, or take power saving steps in response to CPU Idle calls."
1801 This driver will make CPU Idle calls when Linux is idle (unless this
1802 feature is turned off -- see "Do CPU IDLE calls", below). This
1803 should always save battery power, but more complicated APM features
1804 will be dependent on your BIOS implementation. You may need to turn
1805 this option off if your computer hangs at boot time when using APM
1806 support, or if it beeps continuously instead of suspending. Turn
1807 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
1808 T400CDT. This is off by default since most machines do fine without
1809 this feature.
1810
1811config APM_CPU_IDLE
1812 bool "Make CPU Idle calls when idle"
8f9ca475 1813 ---help---
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SR
1814 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
1815 On some machines, this can activate improved power savings, such as
1816 a slowed CPU clock rate, when the machine is idle. These idle calls
1817 are made after the idle loop has run for some length of time (e.g.,
1818 333 mS). On some machines, this will cause a hang at boot time or
1819 whenever the CPU becomes idle. (On machines with more than one CPU,
1820 this option does nothing.)
1821
1822config APM_DISPLAY_BLANK
1823 bool "Enable console blanking using APM"
8f9ca475 1824 ---help---
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SR
1825 Enable console blanking using the APM. Some laptops can use this to
1826 turn off the LCD backlight when the screen blanker of the Linux
1827 virtual console blanks the screen. Note that this is only used by
1828 the virtual console screen blanker, and won't turn off the backlight
1829 when using the X Window system. This also doesn't have anything to
1830 do with your VESA-compliant power-saving monitor. Further, this
1831 option doesn't work for all laptops -- it might not turn off your
1832 backlight at all, or it might print a lot of errors to the console,
1833 especially if you are using gpm.
1834
1835config APM_ALLOW_INTS
1836 bool "Allow interrupts during APM BIOS calls"
8f9ca475 1837 ---help---
e279b6c1
SR
1838 Normally we disable external interrupts while we are making calls to
1839 the APM BIOS as a measure to lessen the effects of a badly behaving
1840 BIOS implementation. The BIOS should reenable interrupts if it
1841 needs to. Unfortunately, some BIOSes do not -- especially those in
1842 many of the newer IBM Thinkpads. If you experience hangs when you
1843 suspend, try setting this to Y. Otherwise, say N.
1844
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SR
1845endif # APM
1846
1847source "arch/x86/kernel/cpu/cpufreq/Kconfig"
1848
1849source "drivers/cpuidle/Kconfig"
1850
27471fdb
AH
1851source "drivers/idle/Kconfig"
1852
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SR
1853endmenu
1854
1855
1856menu "Bus options (PCI etc.)"
1857
1858config PCI
1ac97018 1859 bool "PCI support"
1c858087 1860 default y
e279b6c1 1861 select ARCH_SUPPORTS_MSI if (X86_LOCAL_APIC && X86_IO_APIC)
8f9ca475 1862 ---help---
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SR
1863 Find out whether you have a PCI motherboard. PCI is the name of a
1864 bus system, i.e. the way the CPU talks to the other stuff inside
1865 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1866 VESA. If you have PCI, say Y, otherwise N.
1867
e279b6c1
SR
1868choice
1869 prompt "PCI access mode"
efefa6f6 1870 depends on X86_32 && PCI
e279b6c1
SR
1871 default PCI_GOANY
1872 ---help---
1873 On PCI systems, the BIOS can be used to detect the PCI devices and
1874 determine their configuration. However, some old PCI motherboards
1875 have BIOS bugs and may crash if this is done. Also, some embedded
1876 PCI-based systems don't have any BIOS at all. Linux can also try to
1877 detect the PCI hardware directly without using the BIOS.
1878
1879 With this option, you can specify how Linux should detect the
1880 PCI devices. If you choose "BIOS", the BIOS will be used,
1881 if you choose "Direct", the BIOS won't be used, and if you
1882 choose "MMConfig", then PCI Express MMCONFIG will be used.
1883 If you choose "Any", the kernel will try MMCONFIG, then the
1884 direct access method and falls back to the BIOS if that doesn't
1885 work. If unsure, go with the default, which is "Any".
1886
1887config PCI_GOBIOS
1888 bool "BIOS"
1889
1890config PCI_GOMMCONFIG
1891 bool "MMConfig"
1892
1893config PCI_GODIRECT
1894 bool "Direct"
1895
3ef0e1f8
AS
1896config PCI_GOOLPC
1897 bool "OLPC"
1898 depends on OLPC
1899
2bdd1b03
AS
1900config PCI_GOANY
1901 bool "Any"
1902
e279b6c1
SR
1903endchoice
1904
1905config PCI_BIOS
3c2362e6 1906 def_bool y
efefa6f6 1907 depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY)
e279b6c1
SR
1908
1909# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
1910config PCI_DIRECT
3c2362e6 1911 def_bool y
efefa6f6 1912 depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC))
e279b6c1
SR
1913
1914config PCI_MMCONFIG
3c2362e6 1915 def_bool y
5f0db7a2 1916 depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY)
e279b6c1 1917
3ef0e1f8 1918config PCI_OLPC
2bdd1b03
AS
1919 def_bool y
1920 depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY)
3ef0e1f8 1921
e279b6c1 1922config PCI_DOMAINS
3c2362e6 1923 def_bool y
e279b6c1 1924 depends on PCI
e279b6c1
SR
1925
1926config PCI_MMCONFIG
1927 bool "Support mmconfig PCI config space access"
1928 depends on X86_64 && PCI && ACPI
1929
3f6ea84a
IS
1930config PCI_CNB20LE_QUIRK
1931 bool "Read CNB20LE Host Bridge Windows"
1932 depends on PCI
1933 help
1934 Read the PCI windows out of the CNB20LE host bridge. This allows
1935 PCI hotplug to work on systems with the CNB20LE chipset which do
1936 not have ACPI.
1937
e279b6c1
SR
1938config DMAR
1939 bool "Support for DMA Remapping Devices (EXPERIMENTAL)"
4cf2e75d 1940 depends on PCI_MSI && ACPI && EXPERIMENTAL
e279b6c1
SR
1941 help
1942 DMA remapping (DMAR) devices support enables independent address
1943 translations for Direct Memory Access (DMA) from devices.
1944 These DMA remapping devices are reported via ACPI tables
1945 and include PCI device scope covered by these DMA
1946 remapping devices.
1947
0cd5c3c8 1948config DMAR_DEFAULT_ON
f6be37fd 1949 def_bool y
0cd5c3c8
KM
1950 prompt "Enable DMA Remapping Devices by default"
1951 depends on DMAR
1952 help
1953 Selecting this option will enable a DMAR device at boot time if
1954 one is found. If this option is not selected, DMAR support can
1955 be enabled by passing intel_iommu=on to the kernel. It is
1956 recommended you say N here while the DMAR code remains
1957 experimental.
1958
62edf5dc 1959config DMAR_BROKEN_GFX_WA
6fc108a0 1960 bool "Workaround broken graphics drivers (going away soon)"
0c02a20f 1961 depends on DMAR && BROKEN
62edf5dc
DW
1962 ---help---
1963 Current Graphics drivers tend to use physical address
1964 for DMA and avoid using DMA APIs. Setting this config
1965 option permits the IOMMU driver to set a unity map for
1966 all the OS-visible memory. Hence the driver can continue
1967 to use physical addresses for DMA, at least until this
1968 option is removed in the 2.6.32 kernel.
1969
e279b6c1 1970config DMAR_FLOPPY_WA
3c2362e6 1971 def_bool y
e279b6c1 1972 depends on DMAR
8f9ca475 1973 ---help---
c7ab48d2 1974 Floppy disk drivers are known to bypass DMA API calls
8f9ca475
IM
1975 thereby failing to work when IOMMU is enabled. This
1976 workaround will setup a 1:1 mapping for the first
c7ab48d2 1977 16MiB to make floppy (an ISA device) work.
e279b6c1 1978
9fa8c481
SS
1979config INTR_REMAP
1980 bool "Support for Interrupt Remapping (EXPERIMENTAL)"
1981 depends on X86_64 && X86_IO_APIC && PCI_MSI && ACPI && EXPERIMENTAL
8f9ca475
IM
1982 ---help---
1983 Supports Interrupt remapping for IO-APIC and MSI devices.
1984 To use x2apic mode in the CPU's which support x2APIC enhancements or
1985 to support platforms with CPU's having > 8 bit APIC ID, say Y.
9fa8c481 1986
e279b6c1
SR
1987source "drivers/pci/pcie/Kconfig"
1988
1989source "drivers/pci/Kconfig"
1990
1991# x86_64 have no ISA slots, but do have ISA-style DMA.
1992config ISA_DMA_API
3c2362e6 1993 def_bool y
e279b6c1
SR
1994
1995if X86_32
1996
1997config ISA
1998 bool "ISA support"
8f9ca475 1999 ---help---
e279b6c1
SR
2000 Find out whether you have ISA slots on your motherboard. ISA is the
2001 name of a bus system, i.e. the way the CPU talks to the other stuff
2002 inside your box. Other bus systems are PCI, EISA, MicroChannel
2003 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
2004 newer boards don't support it. If you have ISA, say Y, otherwise N.
2005
2006config EISA
2007 bool "EISA support"
2008 depends on ISA
2009 ---help---
2010 The Extended Industry Standard Architecture (EISA) bus was
2011 developed as an open alternative to the IBM MicroChannel bus.
2012
2013 The EISA bus provided some of the features of the IBM MicroChannel
2014 bus while maintaining backward compatibility with cards made for
2015 the older ISA bus. The EISA bus saw limited use between 1988 and
2016 1995 when it was made obsolete by the PCI bus.
2017
2018 Say Y here if you are building a kernel for an EISA-based machine.
2019
2020 Otherwise, say N.
2021
2022source "drivers/eisa/Kconfig"
2023
2024config MCA
72ee6ebb 2025 bool "MCA support"
8f9ca475 2026 ---help---
e279b6c1
SR
2027 MicroChannel Architecture is found in some IBM PS/2 machines and
2028 laptops. It is a bus system similar to PCI or ISA. See
2029 <file:Documentation/mca.txt> (and especially the web page given
2030 there) before attempting to build an MCA bus kernel.
2031
2032source "drivers/mca/Kconfig"
2033
2034config SCx200
2035 tristate "NatSemi SCx200 support"
8f9ca475 2036 ---help---
e279b6c1
SR
2037 This provides basic support for National Semiconductor's
2038 (now AMD's) Geode processors. The driver probes for the
2039 PCI-IDs of several on-chip devices, so its a good dependency
2040 for other scx200_* drivers.
2041
2042 If compiled as a module, the driver is named scx200.
2043
2044config SCx200HR_TIMER
2045 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
2046 depends on SCx200 && GENERIC_TIME
2047 default y
8f9ca475 2048 ---help---
e279b6c1
SR
2049 This driver provides a clocksource built upon the on-chip
2050 27MHz high-resolution timer. Its also a workaround for
2051 NSC Geode SC-1100's buggy TSC, which loses time when the
2052 processor goes idle (as is done by the scheduler). The
2053 other workaround is idle=poll boot option.
2054
3ef0e1f8
AS
2055config OLPC
2056 bool "One Laptop Per Child support"
3c554946 2057 select GPIOLIB
8f9ca475 2058 ---help---
3ef0e1f8
AS
2059 Add support for detecting the unique features of the OLPC
2060 XO hardware.
2061
bc0120fd
SR
2062endif # X86_32
2063
e279b6c1
SR
2064config K8_NB
2065 def_bool y
0e152cd7 2066 depends on CPU_SUP_AMD && PCI
e279b6c1
SR
2067
2068source "drivers/pcmcia/Kconfig"
2069
2070source "drivers/pci/hotplug/Kconfig"
2071
2072endmenu
2073
2074
2075menu "Executable file formats / Emulations"
2076
2077source "fs/Kconfig.binfmt"
2078
2079config IA32_EMULATION
2080 bool "IA32 Emulation"
2081 depends on X86_64
a97f52e6 2082 select COMPAT_BINFMT_ELF
8f9ca475 2083 ---help---
e279b6c1
SR
2084 Include code to run 32-bit programs under a 64-bit kernel. You should
2085 likely turn this on, unless you're 100% sure that you don't have any
2086 32-bit programs left.
2087
2088config IA32_AOUT
8f9ca475
IM
2089 tristate "IA32 a.out support"
2090 depends on IA32_EMULATION
2091 ---help---
2092 Support old a.out binaries in the 32bit emulation.
e279b6c1
SR
2093
2094config COMPAT
3c2362e6 2095 def_bool y
e279b6c1 2096 depends on IA32_EMULATION
e279b6c1
SR
2097
2098config COMPAT_FOR_U64_ALIGNMENT
2099 def_bool COMPAT
2100 depends on X86_64
2101
2102config SYSVIPC_COMPAT
3c2362e6 2103 def_bool y
b8992195 2104 depends on COMPAT && SYSVIPC
e279b6c1
SR
2105
2106endmenu
2107
2108
e5beae16
KP
2109config HAVE_ATOMIC_IOMAP
2110 def_bool y
2111 depends on X86_32
2112
e279b6c1
SR
2113source "net/Kconfig"
2114
2115source "drivers/Kconfig"
2116
2117source "drivers/firmware/Kconfig"
2118
2119source "fs/Kconfig"
2120
e279b6c1
SR
2121source "arch/x86/Kconfig.debug"
2122
2123source "security/Kconfig"
2124
2125source "crypto/Kconfig"
2126
edf88417
AK
2127source "arch/x86/kvm/Kconfig"
2128
e279b6c1 2129source "lib/Kconfig"