[PATCH] i386: Implement CONFIG_PHYSICAL_ALIGN
[deliverable/linux.git] / arch / i386 / Kconfig
CommitLineData
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1#
2# For a description of the syntax of this configuration file,
3# see Documentation/kbuild/kconfig-language.txt.
4#
5
6mainmenu "Linux Kernel Configuration"
7
0d078f6f 8config X86_32
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9 bool
10 default y
11 help
12 This is Linux's home port. Linux was originally native to the Intel
13 386, and runs on all the later x86 processors including the Intel
14 486, 586, Pentiums, and various instruction-set-compatible chips by
15 AMD, Cyrix, and others.
16
6f84fa2f 17config GENERIC_TIME
18 bool
19 default y
20
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21config LOCKDEP_SUPPORT
22 bool
23 default y
24
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25config STACKTRACE_SUPPORT
26 bool
27 default y
28
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29config SEMAPHORE_SLEEPERS
30 bool
31 default y
32
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33config X86
34 bool
35 default y
36
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37config MMU
38 bool
39 default y
40
41config SBUS
42 bool
43
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44config GENERIC_ISA_DMA
45 bool
46 default y
47
48config GENERIC_IOMAP
49 bool
50 default y
51
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52config GENERIC_HWEIGHT
53 bool
54 default y
55
a08b6b79 56config ARCH_MAY_HAVE_PC_FDC
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57 bool
58 default y
59
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60config DMI
61 bool
62 default y
63
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64source "init/Kconfig"
65
66menu "Processor type and features"
67
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68config SMP
69 bool "Symmetric multi-processing support"
70 ---help---
71 This enables support for systems with more than one CPU. If you have
72 a system with only one CPU, like most personal computers, say N. If
73 you have a system with more than one CPU, say Y.
74
75 If you say N here, the kernel will run on single and multiprocessor
76 machines, but will use only one CPU of a multiprocessor machine. If
77 you say Y here, the kernel will run on many, but not all,
78 singleprocessor machines. On a singleprocessor machine, the kernel
79 will run faster if you say N here.
80
81 Note that if you say Y here and choose architecture "586" or
82 "Pentium" under "Processor family", the kernel will not work on 486
83 architectures. Similarly, multiprocessor kernels for the "PPro"
84 architecture may not work on all Pentium based boards.
85
86 People using multiprocessor machines who say Y here should also say
87 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
88 Management" code will be disabled if you say Y here.
89
90 See also the <file:Documentation/smp.txt>,
91 <file:Documentation/i386/IO-APIC.txt>,
92 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
93 <http://www.tldp.org/docs.html#howto>.
94
95 If you don't know what to do here, say N.
96
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97choice
98 prompt "Subarchitecture Type"
99 default X86_PC
100
101config X86_PC
102 bool "PC-compatible"
103 help
104 Choose this option if your computer is a standard PC or compatible.
105
106config X86_ELAN
107 bool "AMD Elan"
108 help
109 Select this for an AMD Elan processor.
110
111 Do not use this option for K6/Athlon/Opteron processors!
112
113 If unsure, choose "PC-compatible" instead.
114
115config X86_VOYAGER
116 bool "Voyager (NCR)"
117 help
118 Voyager is an MCA-based 32-way capable SMP architecture proprietary
119 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
120
121 *** WARNING ***
122
123 If you do not specifically know you have a Voyager based machine,
124 say N here, otherwise the kernel you build will not be bootable.
125
126config X86_NUMAQ
127 bool "NUMAQ (IBM/Sequent)"
905c3995 128 select SMP
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129 select NUMA
130 help
131 This option is used for getting Linux to run on a (IBM/Sequent) NUMA
132 multiquad box. This changes the way that processors are bootstrapped,
133 and uses Clustered Logical APIC addressing mode instead of Flat Logical.
134 You will need a new lynxer.elf file to flash your firmware with - send
135 email to <Martin.Bligh@us.ibm.com>.
136
137config X86_SUMMIT
138 bool "Summit/EXA (IBM x440)"
139 depends on SMP
140 help
141 This option is needed for IBM systems that use the Summit/EXA chipset.
142 In particular, it is needed for the x440.
143
144 If you don't have one of these computers, you should say N here.
38e716aa 145 If you want to build a NUMA kernel, you must select ACPI.
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146
147config X86_BIGSMP
148 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
149 depends on SMP
150 help
151 This option is needed for the systems that have more than 8 CPUs
152 and if the system is not of any sub-arch type above.
153
154 If you don't have such a system, you should say N here.
155
156config X86_VISWS
157 bool "SGI 320/540 (Visual Workstation)"
158 help
159 The SGI Visual Workstation series is an IA32-based workstation
160 based on SGI systems chips with some legacy PC hardware attached.
161
162 Say Y here to create a kernel to run on the SGI 320 or 540.
163
164 A kernel compiled for the Visual Workstation will not run on PCs
165 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
166
167config X86_GENERICARCH
168 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
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169 help
170 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
171 It is intended for a generic binary kernel.
38e716aa 172 If you want a NUMA kernel, select ACPI. We need SRAT for NUMA.
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173
174config X86_ES7000
175 bool "Support for Unisys ES7000 IA32 series"
176 depends on SMP
177 help
178 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
179 supposed to run on an IA32-based Unisys ES7000 system.
180 Only choose this option if you have such a system, otherwise you
181 should say N here.
182
183endchoice
184
185config ACPI_SRAT
186 bool
187 default y
55910b28 188 depends on ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
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189 select ACPI_NUMA
190
191config HAVE_ARCH_PARSE_SRAT
192 bool
193 default y
194 depends on ACPI_SRAT
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195
196config X86_SUMMIT_NUMA
197 bool
198 default y
199 depends on NUMA && (X86_SUMMIT || X86_GENERICARCH)
200
201config X86_CYCLONE_TIMER
202 bool
203 default y
204 depends on X86_SUMMIT || X86_GENERICARCH
205
206config ES7000_CLUSTERED_APIC
207 bool
208 default y
209 depends on SMP && X86_ES7000 && MPENTIUMIII
210
96d55b88 211source "arch/i386/Kconfig.cpu"
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212
213config HPET_TIMER
214 bool "HPET Timer Support"
215 help
216 This enables the use of the HPET for the kernel's internal timer.
217 HPET is the next generation timer replacing legacy 8254s.
218 You can safely choose Y here. However, HPET will only be
219 activated if the platform and the BIOS support this feature.
220 Otherwise the 8254 will be used for timing services.
221
222 Choose N to continue using the legacy 8254 timer.
223
224config HPET_EMULATE_RTC
c91096d8 225 bool
1da177e4 226 depends on HPET_TIMER && RTC=y
c91096d8 227 default y
1da177e4 228
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229config NR_CPUS
230 int "Maximum number of CPUs (2-255)"
231 range 2 255
232 depends on SMP
233 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
234 default "8"
235 help
236 This allows you to specify the maximum number of CPUs which this
237 kernel will support. The maximum supported value is 255 and the
238 minimum value which makes sense is 2.
239
240 This is purely to save memory - each supported CPU adds
241 approximately eight kilobytes to the kernel image.
242
243config SCHED_SMT
244 bool "SMT (Hyperthreading) scheduler support"
96c52749 245 depends on X86_HT
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246 help
247 SMT scheduler support improves the CPU scheduler's decision making
248 when dealing with Intel Pentium 4 chips with HyperThreading at a
249 cost of slightly increased overhead in some places. If unsure say
250 N here.
251
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252config SCHED_MC
253 bool "Multi-core scheduler support"
96c52749 254 depends on X86_HT
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255 default y
256 help
257 Multi-core scheduler support improves the CPU scheduler's decision
258 making when dealing with multi-core CPU chips at a cost of slightly
259 increased overhead in some places. If unsure say N here.
260
cc19ca86 261source "kernel/Kconfig.preempt"
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262
263config X86_UP_APIC
264 bool "Local APIC support on uniprocessors"
874c4fe3 265 depends on !SMP && !(X86_VISWS || X86_VOYAGER || X86_GENERICARCH)
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266 help
267 A local APIC (Advanced Programmable Interrupt Controller) is an
268 integrated interrupt controller in the CPU. If you have a single-CPU
269 system which has a processor with a local APIC, you can say Y here to
270 enable and use it. If you say Y here even though your machine doesn't
271 have a local APIC, then the kernel will still run with no slowdown at
272 all. The local APIC supports CPU-generated self-interrupts (timer,
273 performance counters), and the NMI watchdog which detects hard
274 lockups.
275
276config X86_UP_IOAPIC
277 bool "IO-APIC support on uniprocessors"
278 depends on X86_UP_APIC
279 help
280 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
281 SMP-capable replacement for PC-style interrupt controllers. Most
282 SMP systems and many recent uniprocessor systems have one.
283
284 If you have a single-CPU system with an IO-APIC, you can say Y here
285 to use it. If you say Y here even though your machine doesn't have
286 an IO-APIC, then the kernel will still run with no slowdown at all.
287
288config X86_LOCAL_APIC
289 bool
874c4fe3 290 depends on X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER) || X86_GENERICARCH
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291 default y
292
293config X86_IO_APIC
294 bool
874c4fe3 295 depends on X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER)) || X86_GENERICARCH
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296 default y
297
298config X86_VISWS_APIC
299 bool
300 depends on X86_VISWS
301 default y
302
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303config X86_MCE
304 bool "Machine Check Exception"
305 depends on !X86_VOYAGER
306 ---help---
307 Machine Check Exception support allows the processor to notify the
308 kernel if it detects a problem (e.g. overheating, component failure).
309 The action the kernel takes depends on the severity of the problem,
310 ranging from a warning message on the console, to halting the machine.
311 Your processor must be a Pentium or newer to support this - check the
312 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
313 have a design flaw which leads to false MCE events - hence MCE is
314 disabled on all P5 processors, unless explicitly enabled with "mce"
315 as a boot argument. Similarly, if MCE is built in and creates a
316 problem on some new non-standard machine, you can boot with "nomce"
317 to disable it. MCE support simply ignores non-MCE processors like
318 the 386 and 486, so nearly everyone can say Y here.
319
320config X86_MCE_NONFATAL
321 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
322 depends on X86_MCE
323 help
324 Enabling this feature starts a timer that triggers every 5 seconds which
325 will look at the machine check registers to see if anything happened.
326 Non-fatal problems automatically get corrected (but still logged).
327 Disable this if you don't want to see these messages.
328 Seeing the messages this option prints out may be indicative of dying hardware,
329 or out-of-spec (ie, overclocked) hardware.
330 This option only does something on certain CPUs.
331 (AMD Athlon/Duron and Intel Pentium 4)
332
333config X86_MCE_P4THERMAL
334 bool "check for P4 thermal throttling interrupt."
335 depends on X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
336 help
337 Enabling this feature will cause a message to be printed when the P4
338 enters thermal throttling.
339
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340config VM86
341 default y
342 bool "Enable VM86 support" if EMBEDDED
343 help
344 This option is required by programs like DOSEMU to run 16-bit legacy
345 code on X86 processors. It also may be needed by software like
346 XFree86 to initialize some video cards via BIOS. Disabling this
347 option saves about 6k.
348
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349config TOSHIBA
350 tristate "Toshiba Laptop support"
351 ---help---
352 This adds a driver to safely access the System Management Mode of
353 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
354 not work on models with a Phoenix BIOS. The System Management Mode
355 is used to set the BIOS and power saving options on Toshiba portables.
356
357 For information on utilities to make use of this driver see the
358 Toshiba Linux utilities web site at:
359 <http://www.buzzard.org.uk/toshiba/>.
360
361 Say Y if you intend to run this kernel on a Toshiba portable.
362 Say N otherwise.
363
364config I8K
365 tristate "Dell laptop support"
366 ---help---
367 This adds a driver to safely access the System Management Mode
368 of the CPU on the Dell Inspiron 8000. The System Management Mode
369 is used to read cpu temperature and cooling fan status and to
370 control the fans on the I8K portables.
371
372 This driver has been tested only on the Inspiron 8000 but it may
373 also work with other Dell laptops. You can force loading on other
374 models by passing the parameter `force=1' to the module. Use at
375 your own risk.
376
377 For information on utilities to make use of this driver see the
378 I8K Linux utilities web site at:
379 <http://people.debian.org/~dz/i8k/>
380
381 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
382 Say N otherwise.
383
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384config X86_REBOOTFIXUPS
385 bool "Enable X86 board specific fixups for reboot"
386 depends on X86
387 default n
388 ---help---
389 This enables chipset and/or board specific fixups to be done
390 in order to get reboot to work correctly. This is only needed on
391 some combinations of hardware and BIOS. The symptom, for which
392 this config is intended, is when reboot ends with a stalled/hung
393 system.
394
395 Currently, the only fixup is for the Geode GX1/CS5530A/TROM2.1.
396 combination.
397
398 Say Y if you want to enable the fixup. Currently, it's safe to
399 enable this option even if you don't need it.
400 Say N otherwise.
401
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402config MICROCODE
403 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
9a4b9efa 404 select FW_LOADER
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405 ---help---
406 If you say Y here and also to "/dev file system support" in the
407 'File systems' section, you will be able to update the microcode on
408 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
409 Pentium III, Pentium 4, Xeon etc. You will obviously need the
410 actual microcode binary data itself which is not shipped with the
411 Linux kernel.
412
413 For latest news and information on obtaining all the required
414 ingredients for this driver, check:
415 <http://www.urbanmyth.org/microcode/>.
416
417 To compile this driver as a module, choose M here: the
418 module will be called microcode.
419
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420config MICROCODE_OLD_INTERFACE
421 bool
422 depends on MICROCODE
423 default y
424
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425config X86_MSR
426 tristate "/dev/cpu/*/msr - Model-specific register support"
427 help
428 This device gives privileged processes access to the x86
429 Model-Specific Registers (MSRs). It is a character device with
430 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
431 MSR accesses are directed to a specific CPU on multi-processor
432 systems.
433
434config X86_CPUID
435 tristate "/dev/cpu/*/cpuid - CPU information support"
436 help
437 This device gives processes access to the x86 CPUID instruction to
438 be executed on a specific processor. It is a character device
439 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
440 /dev/cpu/31/cpuid.
441
442source "drivers/firmware/Kconfig"
443
444choice
445 prompt "High Memory Support"
446 default NOHIGHMEM
447
448config NOHIGHMEM
449 bool "off"
905c3995 450 depends on !X86_NUMAQ
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451 ---help---
452 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
453 However, the address space of 32-bit x86 processors is only 4
454 Gigabytes large. That means that, if you have a large amount of
455 physical memory, not all of it can be "permanently mapped" by the
456 kernel. The physical memory that's not permanently mapped is called
457 "high memory".
458
459 If you are compiling a kernel which will never run on a machine with
460 more than 1 Gigabyte total physical RAM, answer "off" here (default
461 choice and suitable for most users). This will result in a "3GB/1GB"
462 split: 3GB are mapped so that each process sees a 3GB virtual memory
463 space and the remaining part of the 4GB virtual memory space is used
464 by the kernel to permanently map as much physical memory as
465 possible.
466
467 If the machine has between 1 and 4 Gigabytes physical RAM, then
468 answer "4GB" here.
469
470 If more than 4 Gigabytes is used then answer "64GB" here. This
471 selection turns Intel PAE (Physical Address Extension) mode on.
472 PAE implements 3-level paging on IA32 processors. PAE is fully
473 supported by Linux, PAE mode is implemented on all recent Intel
474 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
475 then the kernel will not boot on CPUs that don't support PAE!
476
477 The actual amount of total physical memory will either be
478 auto detected or can be forced by using a kernel command line option
479 such as "mem=256M". (Try "man bootparam" or see the documentation of
480 your boot loader (lilo or loadlin) about how to pass options to the
481 kernel at boot time.)
482
483 If unsure, say "off".
484
485config HIGHMEM4G
486 bool "4GB"
905c3995 487 depends on !X86_NUMAQ
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488 help
489 Select this if you have a 32-bit processor and between 1 and 4
490 gigabytes of physical RAM.
491
492config HIGHMEM64G
493 bool "64GB"
4be68a78 494 depends on X86_CMPXCHG64
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495 help
496 Select this if you have a 32-bit processor and more than 4
497 gigabytes of physical RAM.
498
499endchoice
500
975b3d3d 501choice
753b9f86 502 depends on EXPERIMENTAL
9539d4e7 503 prompt "Memory split" if EMBEDDED
975b3d3d
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504 default VMSPLIT_3G
505 help
506 Select the desired split between kernel and user memory.
507
508 If the address range available to the kernel is less than the
509 physical memory installed, the remaining memory will be available
510 as "high memory". Accessing high memory is a little more costly
511 than low memory, as it needs to be mapped into the kernel first.
512 Note that increasing the kernel address space limits the range
513 available to user programs, making the address space there
514 tighter. Selecting anything other than the default 3G/1G split
515 will also likely make your kernel incompatible with binary-only
516 kernel modules.
517
518 If you are not absolutely sure what you are doing, leave this
519 option alone!
520
521 config VMSPLIT_3G
522 bool "3G/1G user/kernel split"
523 config VMSPLIT_3G_OPT
753b9f86 524 depends on !HIGHMEM
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525 bool "3G/1G user/kernel split (for full 1G low memory)"
526 config VMSPLIT_2G
527 bool "2G/2G user/kernel split"
528 config VMSPLIT_1G
529 bool "1G/3G user/kernel split"
530endchoice
531
532config PAGE_OFFSET
533 hex
534 default 0xB0000000 if VMSPLIT_3G_OPT
535 default 0x78000000 if VMSPLIT_2G
536 default 0x40000000 if VMSPLIT_1G
537 default 0xC0000000
538
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539config HIGHMEM
540 bool
541 depends on HIGHMEM64G || HIGHMEM4G
542 default y
543
544config X86_PAE
545 bool
546 depends on HIGHMEM64G
547 default y
6550e07f 548 select RESOURCES_64BIT
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549
550# Common NUMA Features
551config NUMA
552 bool "Numa Memory Allocation and Scheduler Support"
38e716aa 553 depends on SMP && HIGHMEM64G && (X86_NUMAQ || (X86_SUMMIT || X86_GENERICARCH) && ACPI)
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554 default n if X86_PC
555 default y if (X86_NUMAQ || X86_SUMMIT)
556
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557comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
558 depends on X86_SUMMIT && (!HIGHMEM64G || !ACPI)
559
c80d79d7
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560config NODES_SHIFT
561 int
562 default "4" if X86_NUMAQ
563 default "3"
564 depends on NEED_MULTIPLE_NODES
565
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566config HAVE_ARCH_BOOTMEM_NODE
567 bool
568 depends on NUMA
569 default y
570
af705362 571config ARCH_HAVE_MEMORY_PRESENT
1da177e4
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572 bool
573 depends on DISCONTIGMEM
574 default y
575
576config NEED_NODE_MEMMAP_SIZE
577 bool
05b79bdc 578 depends on DISCONTIGMEM || SPARSEMEM
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579 default y
580
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581config HAVE_ARCH_ALLOC_REMAP
582 bool
583 depends on NUMA
584 default y
585
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586config ARCH_FLATMEM_ENABLE
587 def_bool y
588 depends on (ARCH_SELECT_MEMORY_MODEL && X86_PC)
589
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590config ARCH_DISCONTIGMEM_ENABLE
591 def_bool y
592 depends on NUMA
593
594config ARCH_DISCONTIGMEM_DEFAULT
595 def_bool y
596 depends on NUMA
597
598config ARCH_SPARSEMEM_ENABLE
599 def_bool y
215c3409
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600 depends on (NUMA || (X86_PC && EXPERIMENTAL))
601 select SPARSEMEM_STATIC
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602
603config ARCH_SELECT_MEMORY_MODEL
604 def_bool y
605 depends on ARCH_SPARSEMEM_ENABLE
606
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607config ARCH_POPULATES_NODE_MAP
608 def_bool y
3f22ab27 609
4cfee88a 610source "mm/Kconfig"
b159d43f 611
1da177e4
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612config HIGHPTE
613 bool "Allocate 3rd-level pagetables from highmem"
614 depends on HIGHMEM4G || HIGHMEM64G
615 help
616 The VM uses one page table entry for each page of physical memory.
617 For systems with a lot of RAM, this can be wasteful of precious
618 low memory. Setting this option will put user-space page table
619 entries in high memory.
620
621config MATH_EMULATION
622 bool "Math emulation"
623 ---help---
624 Linux can emulate a math coprocessor (used for floating point
625 operations) if you don't have one. 486DX and Pentium processors have
626 a math coprocessor built in, 486SX and 386 do not, unless you added
627 a 487DX or 387, respectively. (The messages during boot time can
628 give you some hints here ["man dmesg"].) Everyone needs either a
629 coprocessor or this emulation.
630
631 If you don't have a math coprocessor, you need to say Y here; if you
632 say Y here even though you have a coprocessor, the coprocessor will
633 be used nevertheless. (This behavior can be changed with the kernel
634 command line option "no387", which comes handy if your coprocessor
635 is broken. Try "man bootparam" or see the documentation of your boot
636 loader (lilo or loadlin) about how to pass options to the kernel at
637 boot time.) This means that it is a good idea to say Y here if you
638 intend to use this kernel on different machines.
639
640 More information about the internals of the Linux math coprocessor
641 emulation can be found in <file:arch/i386/math-emu/README>.
642
643 If you are not sure, say Y; apart from resulting in a 66 KB bigger
644 kernel, it won't hurt.
645
646config MTRR
647 bool "MTRR (Memory Type Range Register) support"
648 ---help---
649 On Intel P6 family processors (Pentium Pro, Pentium II and later)
650 the Memory Type Range Registers (MTRRs) may be used to control
651 processor access to memory ranges. This is most useful if you have
652 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
653 allows bus write transfers to be combined into a larger transfer
654 before bursting over the PCI/AGP bus. This can increase performance
655 of image write operations 2.5 times or more. Saying Y here creates a
656 /proc/mtrr file which may be used to manipulate your processor's
657 MTRRs. Typically the X server should use this.
658
659 This code has a reasonably generic interface so that similar
660 control registers on other processors can be easily supported
661 as well:
662
663 The Cyrix 6x86, 6x86MX and M II processors have Address Range
664 Registers (ARRs) which provide a similar functionality to MTRRs. For
665 these, the ARRs are used to emulate the MTRRs.
666 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
667 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
668 write-combining. All of these processors are supported by this code
669 and it makes sense to say Y here if you have one of them.
670
671 Saying Y here also fixes a problem with buggy SMP BIOSes which only
672 set the MTRRs for the boot CPU and not for the secondary CPUs. This
673 can lead to all sorts of problems, so it's good to say Y here.
674
675 You can safely say Y even if your machine doesn't have MTRRs, you'll
676 just add about 9 KB to your kernel.
677
678 See <file:Documentation/mtrr.txt> for more information.
679
680config EFI
c8e5429e 681 bool "Boot from EFI support"
1da177e4
LT
682 depends on ACPI
683 default n
684 ---help---
4b3f686d 685 This enables the kernel to boot on EFI platforms using
1da177e4
LT
686 system configuration information passed to it from the firmware.
687 This also enables the kernel to use any EFI runtime services that are
688 available (such as the EFI variable services).
689
690 This option is only useful on systems that have EFI firmware
691 and will result in a kernel image that is ~8k larger. In addition,
692 you must use the latest ELILO loader available at
693 <http://elilo.sourceforge.net> in order to take advantage of
694 kernel initialization using EFI information (neither GRUB nor LILO know
695 anything about EFI). However, even with this option, the resultant
696 kernel should continue to boot on existing non-EFI platforms.
697
698config IRQBALANCE
699 bool "Enable kernel irq balancing"
700 depends on SMP && X86_IO_APIC
701 default y
702 help
703 The default yes will allow the kernel to do irq load balancing.
704 Saying no will keep the kernel from doing irq load balancing.
705
1da177e4
LT
706# turning this on wastes a bunch of space.
707# Summit needs it only when NUMA is on
708config BOOT_IOREMAP
709 bool
710 depends on (((X86_SUMMIT || X86_GENERICARCH) && NUMA) || (X86 && EFI))
711 default y
712
713config REGPARM
69ef4141 714 bool "Use register arguments"
b824eb60 715 default y
1da177e4 716 help
b824eb60
IM
717 Compile the kernel with -mregparm=3. This instructs gcc to use
718 a more efficient function call ABI which passes the first three
719 arguments of a function call via registers, which results in denser
720 and faster code.
721
722 If this option is disabled, then the default ABI of passing
723 arguments via the stack is used.
724
725 If unsure, say Y.
1da177e4 726
1da177e4
LT
727config SECCOMP
728 bool "Enable seccomp to safely compute untrusted bytecode"
729 depends on PROC_FS
730 default y
731 help
732 This kernel feature is useful for number crunching applications
733 that may need to compute untrusted bytecode during their
734 execution. By using pipes or other transports made available to
735 the process as file descriptors supporting the read/write
736 syscalls, it's possible to isolate those applications in
737 their own address space using seccomp. Once seccomp is
738 enabled via /proc/<pid>/seccomp, it cannot be disabled
739 and the task is only allowed to execute a few safe syscalls
740 defined by each seccomp mode.
741
742 If unsure, say Y. Only embedded should say N here.
743
59121003
CL
744source kernel/Kconfig.hz
745
5033cba0 746config KEXEC
371c2f27 747 bool "kexec system call"
5033cba0
EB
748 help
749 kexec is a system call that implements the ability to shutdown your
750 current kernel, and to start another kernel. It is like a reboot
48a1204c 751 but it is independent of the system firmware. And like a reboot
5033cba0
EB
752 you can start any kernel with it, not just Linux.
753
1f1332f7 754 The name comes from the similarity to the exec system call.
5033cba0
EB
755
756 It is an ongoing process to be certain the hardware in a machine
757 is properly shutdown, so do not be surprised if this code does not
758 initially work for you. It may help to enable device hotplugging
759 support. As of this writing the exact hardware interface is
760 strongly in flux, so no good recommendation can be made.
761
5f016456
VG
762config CRASH_DUMP
763 bool "kernel crash dumps (EXPERIMENTAL)"
5f016456
VG
764 depends on EXPERIMENTAL
765 depends on HIGHMEM
766 help
767 Generate crash dump after being started by kexec.
1edf7778
AK
768 This should be normally only set in special crash dump kernels
769 which are loaded in the main kernel with kexec-tools into
770 a specially reserved region and then later executed after
771 a crash by kdump/kexec. The crash dump kernel must be compiled
772 to a memory address not used by the main kernel or BIOS using
773 PHYSICAL_START.
774 For more details see Documentation/kdump/kdump.txt
05970d47 775
968de4f0
EB
776config RELOCATABLE
777 bool "Build a relocatable kernel"
778 help
779 This build a kernel image that retains relocation information
780 so it can be loaded someplace besides the default 1MB.
781 The relocations tend to the kernel binary about 10% larger,
782 but are discarded at runtime.
783
784 One use is for the kexec on panic case where the recovery kernel
785 must live at a different physical address than the primary
786 kernel.
787
e69f202d
VG
788config PHYSICAL_ALIGN
789 hex "Alignment value to which kernel should be aligned"
05970d47 790 default "0x100000"
e69f202d
VG
791 range 0x2000 0x400000
792 help
793 This value puts the alignment restrictions on physical address
794 where kernel is loaded and run from. Kernel is compiled for an
795 address which meets above alignment restriction.
796
797 If bootloader loads the kernel at a non-aligned address and
798 CONFIG_RELOCATABLE is set, kernel will move itself to nearest
799 address aligned to above value and run from there.
800
801 If bootloader loads the kernel at a non-aligned address and
802 CONFIG_RELOCATABLE is not set, kernel will ignore the run time
803 load address and decompress itself to the address it has been
804 compiled for and run from there. The address for which kernel is
805 compiled already meets above alignment restrictions. Hence the
806 end result is that kernel runs from a physical address meeting
807 above alignment restrictions.
05970d47
MS
808
809 Don't change this unless you know what you are doing.
810
ce63ad78
RD
811config HOTPLUG_CPU
812 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
35076bdf 813 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
ce63ad78 814 ---help---
b2d596d8
PM
815 Say Y here to experiment with turning CPUs off and on, and to
816 enable suspend on SMP systems. CPUs can be controlled through
817 /sys/devices/system/cpu.
ce63ad78 818
e6e5494c
IM
819config COMPAT_VDSO
820 bool "Compat VDSO support"
821 default y
052e7994 822 depends on !PARAVIRT
e6e5494c
IM
823 help
824 Map the VDSO to the predictable old-style address too.
825 ---help---
826 Say N here if you are running a sufficiently recent glibc
827 version (2.3.3 or later), to remove the high-mapped
828 VDSO mapping and to exclusively use the randomized VDSO.
829
830 If unsure, say Y.
ce63ad78 831
1da177e4
LT
832endmenu
833
cc57637b
YG
834config ARCH_ENABLE_MEMORY_HOTPLUG
835 def_bool y
836 depends on HIGHMEM
1da177e4
LT
837
838menu "Power management options (ACPI, APM)"
839 depends on !X86_VOYAGER
840
841source kernel/power/Kconfig
842
843source "drivers/acpi/Kconfig"
844
845menu "APM (Advanced Power Management) BIOS Support"
846depends on PM && !X86_VISWS
847
848config APM
849 tristate "APM (Advanced Power Management) BIOS support"
987d4613 850 depends on PM
1da177e4
LT
851 ---help---
852 APM is a BIOS specification for saving power using several different
853 techniques. This is mostly useful for battery powered laptops with
854 APM compliant BIOSes. If you say Y here, the system time will be
855 reset after a RESUME operation, the /proc/apm device will provide
856 battery status information, and user-space programs will receive
857 notification of APM "events" (e.g. battery status change).
858
859 If you select "Y" here, you can disable actual use of the APM
860 BIOS by passing the "apm=off" option to the kernel at boot time.
861
862 Note that the APM support is almost completely disabled for
863 machines with more than one CPU.
864
865 In order to use APM, you will need supporting software. For location
866 and more information, read <file:Documentation/pm.txt> and the
867 Battery Powered Linux mini-HOWTO, available from
868 <http://www.tldp.org/docs.html#howto>.
869
870 This driver does not spin down disk drives (see the hdparm(8)
871 manpage ("man 8 hdparm") for that), and it doesn't turn off
872 VESA-compliant "green" monitors.
873
874 This driver does not support the TI 4000M TravelMate and the ACER
875 486/DX4/75 because they don't have compliant BIOSes. Many "green"
876 desktop machines also don't have compliant BIOSes, and this driver
877 may cause those machines to panic during the boot phase.
878
879 Generally, if you don't have a battery in your machine, there isn't
880 much point in using this driver and you should say N. If you get
881 random kernel OOPSes or reboots that don't seem to be related to
882 anything, try disabling/enabling this option (or disabling/enabling
883 APM in your BIOS).
884
885 Some other things you should try when experiencing seemingly random,
886 "weird" problems:
887
888 1) make sure that you have enough swap space and that it is
889 enabled.
890 2) pass the "no-hlt" option to the kernel
891 3) switch on floating point emulation in the kernel and pass
892 the "no387" option to the kernel
893 4) pass the "floppy=nodma" option to the kernel
894 5) pass the "mem=4M" option to the kernel (thereby disabling
895 all but the first 4 MB of RAM)
896 6) make sure that the CPU is not over clocked.
897 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
898 8) disable the cache from your BIOS settings
899 9) install a fan for the video card or exchange video RAM
900 10) install a better fan for the CPU
901 11) exchange RAM chips
902 12) exchange the motherboard.
903
904 To compile this driver as a module, choose M here: the
905 module will be called apm.
906
907config APM_IGNORE_USER_SUSPEND
908 bool "Ignore USER SUSPEND"
909 depends on APM
910 help
911 This option will ignore USER SUSPEND requests. On machines with a
912 compliant APM BIOS, you want to say N. However, on the NEC Versa M
913 series notebooks, it is necessary to say Y because of a BIOS bug.
914
915config APM_DO_ENABLE
916 bool "Enable PM at boot time"
917 depends on APM
918 ---help---
919 Enable APM features at boot time. From page 36 of the APM BIOS
920 specification: "When disabled, the APM BIOS does not automatically
921 power manage devices, enter the Standby State, enter the Suspend
922 State, or take power saving steps in response to CPU Idle calls."
923 This driver will make CPU Idle calls when Linux is idle (unless this
924 feature is turned off -- see "Do CPU IDLE calls", below). This
925 should always save battery power, but more complicated APM features
926 will be dependent on your BIOS implementation. You may need to turn
927 this option off if your computer hangs at boot time when using APM
928 support, or if it beeps continuously instead of suspending. Turn
929 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
930 T400CDT. This is off by default since most machines do fine without
931 this feature.
932
933config APM_CPU_IDLE
934 bool "Make CPU Idle calls when idle"
935 depends on APM
936 help
937 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
938 On some machines, this can activate improved power savings, such as
939 a slowed CPU clock rate, when the machine is idle. These idle calls
940 are made after the idle loop has run for some length of time (e.g.,
941 333 mS). On some machines, this will cause a hang at boot time or
942 whenever the CPU becomes idle. (On machines with more than one CPU,
943 this option does nothing.)
944
945config APM_DISPLAY_BLANK
946 bool "Enable console blanking using APM"
947 depends on APM
948 help
949 Enable console blanking using the APM. Some laptops can use this to
950 turn off the LCD backlight when the screen blanker of the Linux
951 virtual console blanks the screen. Note that this is only used by
952 the virtual console screen blanker, and won't turn off the backlight
953 when using the X Window system. This also doesn't have anything to
954 do with your VESA-compliant power-saving monitor. Further, this
955 option doesn't work for all laptops -- it might not turn off your
956 backlight at all, or it might print a lot of errors to the console,
957 especially if you are using gpm.
958
959config APM_RTC_IS_GMT
960 bool "RTC stores time in GMT"
961 depends on APM
962 help
963 Say Y here if your RTC (Real Time Clock a.k.a. hardware clock)
964 stores the time in GMT (Greenwich Mean Time). Say N if your RTC
965 stores localtime.
966
967 It is in fact recommended to store GMT in your RTC, because then you
968 don't have to worry about daylight savings time changes. The only
969 reason not to use GMT in your RTC is if you also run a broken OS
970 that doesn't understand GMT.
971
972config APM_ALLOW_INTS
973 bool "Allow interrupts during APM BIOS calls"
974 depends on APM
975 help
976 Normally we disable external interrupts while we are making calls to
977 the APM BIOS as a measure to lessen the effects of a badly behaving
978 BIOS implementation. The BIOS should reenable interrupts if it
979 needs to. Unfortunately, some BIOSes do not -- especially those in
980 many of the newer IBM Thinkpads. If you experience hangs when you
981 suspend, try setting this to Y. Otherwise, say N.
982
983config APM_REAL_MODE_POWER_OFF
984 bool "Use real mode APM BIOS call to power off"
985 depends on APM
986 help
987 Use real mode APM BIOS calls to switch off the computer. This is
988 a work-around for a number of buggy BIOSes. Switch this option on if
989 your computer crashes instead of powering off properly.
990
991endmenu
992
993source "arch/i386/kernel/cpu/cpufreq/Kconfig"
994
995endmenu
996
997menu "Bus options (PCI, PCMCIA, EISA, MCA, ISA)"
998
999config PCI
1000 bool "PCI support" if !X86_VISWS
1001 depends on !X86_VOYAGER
1002 default y if X86_VISWS
1003 help
1004 Find out whether you have a PCI motherboard. PCI is the name of a
1005 bus system, i.e. the way the CPU talks to the other stuff inside
1006 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1007 VESA. If you have PCI, say Y, otherwise N.
1008
1009 The PCI-HOWTO, available from
1010 <http://www.tldp.org/docs.html#howto>, contains valuable
1011 information about which PCI hardware does work under Linux and which
1012 doesn't.
1013
1014choice
1015 prompt "PCI access mode"
1016 depends on PCI && !X86_VISWS
1017 default PCI_GOANY
1018 ---help---
1019 On PCI systems, the BIOS can be used to detect the PCI devices and
1020 determine their configuration. However, some old PCI motherboards
1021 have BIOS bugs and may crash if this is done. Also, some embedded
1022 PCI-based systems don't have any BIOS at all. Linux can also try to
1023 detect the PCI hardware directly without using the BIOS.
1024
1025 With this option, you can specify how Linux should detect the
1026 PCI devices. If you choose "BIOS", the BIOS will be used,
1027 if you choose "Direct", the BIOS won't be used, and if you
1028 choose "MMConfig", then PCI Express MMCONFIG will be used.
1029 If you choose "Any", the kernel will try MMCONFIG, then the
1030 direct access method and falls back to the BIOS if that doesn't
1031 work. If unsure, go with the default, which is "Any".
1032
1033config PCI_GOBIOS
1034 bool "BIOS"
1035
1036config PCI_GOMMCONFIG
1037 bool "MMConfig"
1038
1039config PCI_GODIRECT
1040 bool "Direct"
1041
1042config PCI_GOANY
1043 bool "Any"
1044
1045endchoice
1046
1047config PCI_BIOS
1048 bool
1049 depends on !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1050 default y
1051
1052config PCI_DIRECT
1053 bool
1054 depends on PCI && ((PCI_GODIRECT || PCI_GOANY) || X86_VISWS)
1055 default y
1056
1057config PCI_MMCONFIG
1058 bool
8aadff7d 1059 depends on PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1da177e4
LT
1060 default y
1061
1062source "drivers/pci/pcie/Kconfig"
1063
1064source "drivers/pci/Kconfig"
1065
5cae841b
AV
1066config ISA_DMA_API
1067 bool
1068 default y
1069
1da177e4
LT
1070config ISA
1071 bool "ISA support"
1072 depends on !(X86_VOYAGER || X86_VISWS)
1073 help
1074 Find out whether you have ISA slots on your motherboard. ISA is the
1075 name of a bus system, i.e. the way the CPU talks to the other stuff
1076 inside your box. Other bus systems are PCI, EISA, MicroChannel
1077 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1078 newer boards don't support it. If you have ISA, say Y, otherwise N.
1079
1080config EISA
1081 bool "EISA support"
1082 depends on ISA
1083 ---help---
1084 The Extended Industry Standard Architecture (EISA) bus was
1085 developed as an open alternative to the IBM MicroChannel bus.
1086
1087 The EISA bus provided some of the features of the IBM MicroChannel
1088 bus while maintaining backward compatibility with cards made for
1089 the older ISA bus. The EISA bus saw limited use between 1988 and
1090 1995 when it was made obsolete by the PCI bus.
1091
1092 Say Y here if you are building a kernel for an EISA-based machine.
1093
1094 Otherwise, say N.
1095
1096source "drivers/eisa/Kconfig"
1097
1098config MCA
1099 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1100 default y if X86_VOYAGER
1101 help
1102 MicroChannel Architecture is found in some IBM PS/2 machines and
1103 laptops. It is a bus system similar to PCI or ISA. See
1104 <file:Documentation/mca.txt> (and especially the web page given
1105 there) before attempting to build an MCA bus kernel.
1106
1107source "drivers/mca/Kconfig"
1108
1109config SCx200
1110 tristate "NatSemi SCx200 support"
1111 depends on !X86_VOYAGER
1112 help
6ae7440e
JC
1113 This provides basic support for National Semiconductor's
1114 (now AMD's) Geode processors. The driver probes for the
1115 PCI-IDs of several on-chip devices, so its a good dependency
1116 for other scx200_* drivers.
1da177e4 1117
6ae7440e 1118 If compiled as a module, the driver is named scx200.
1da177e4 1119
6ae7440e
JC
1120config SCx200HR_TIMER
1121 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1122 depends on SCx200 && GENERIC_TIME
1123 default y
1124 help
1125 This driver provides a clocksource built upon the on-chip
1126 27MHz high-resolution timer. Its also a workaround for
1127 NSC Geode SC-1100's buggy TSC, which loses time when the
1128 processor goes idle (as is done by the scheduler). The
1129 other workaround is idle=poll boot option.
1da177e4 1130
a32073bf
AK
1131config K8_NB
1132 def_bool y
1133 depends on AGP_AMD64
1134
1da177e4
LT
1135source "drivers/pcmcia/Kconfig"
1136
1137source "drivers/pci/hotplug/Kconfig"
1138
1139endmenu
1140
1141menu "Executable file formats"
1142
1143source "fs/Kconfig.binfmt"
1144
1145endmenu
1146
d5950b43
SR
1147source "net/Kconfig"
1148
1da177e4
LT
1149source "drivers/Kconfig"
1150
1151source "fs/Kconfig"
1152
cd6b0762
PP
1153menu "Instrumentation Support"
1154 depends on EXPERIMENTAL
1155
1da177e4
LT
1156source "arch/i386/oprofile/Kconfig"
1157
cd6b0762
PP
1158config KPROBES
1159 bool "Kprobes (EXPERIMENTAL)"
3a872d89 1160 depends on KALLSYMS && EXPERIMENTAL && MODULES
cd6b0762
PP
1161 help
1162 Kprobes allows you to trap at almost any kernel address and
1163 execute a callback function. register_kprobe() establishes
1164 a probepoint and specifies the callback. Kprobes is useful
1165 for kernel debugging, non-intrusive instrumentation and testing.
1166 If in doubt, say "N".
1167endmenu
1168
1da177e4
LT
1169source "arch/i386/Kconfig.debug"
1170
1171source "security/Kconfig"
1172
1173source "crypto/Kconfig"
1174
1175source "lib/Kconfig"
1176
1177#
1178# Use the generic interrupt handling code in kernel/irq/:
1179#
1180config GENERIC_HARDIRQS
1181 bool
1182 default y
1183
1184config GENERIC_IRQ_PROBE
1185 bool
1186 default y
1187
54d5d424
AR
1188config GENERIC_PENDING_IRQ
1189 bool
1190 depends on GENERIC_HARDIRQS && SMP
1191 default y
1192
1da177e4
LT
1193config X86_SMP
1194 bool
1195 depends on SMP && !X86_VOYAGER
1196 default y
1197
1198config X86_HT
1199 bool
1200 depends on SMP && !(X86_VISWS || X86_VOYAGER)
1201 default y
1202
1203config X86_BIOS_REBOOT
1204 bool
1205 depends on !(X86_VISWS || X86_VOYAGER)
1206 default y
1207
1208config X86_TRAMPOLINE
1209 bool
1210 depends on X86_SMP || (X86_VOYAGER && SMP)
1211 default y
97fc79f9
TG
1212
1213config KTIME_SCALAR
1214 bool
1215 default y
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