[PATCH] lockdep: stacktrace subsystem, i386 support
[deliverable/linux.git] / arch / i386 / Kconfig
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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 STACKTRACE_SUPPORT
22 bool
23 default y
24
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25config SEMAPHORE_SLEEPERS
26 bool
27 default y
28
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29config X86
30 bool
31 default y
32
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33config MMU
34 bool
35 default y
36
37config SBUS
38 bool
39
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40config GENERIC_ISA_DMA
41 bool
42 default y
43
44config GENERIC_IOMAP
45 bool
46 default y
47
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48config GENERIC_HWEIGHT
49 bool
50 default y
51
a08b6b79 52config ARCH_MAY_HAVE_PC_FDC
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53 bool
54 default y
55
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56config DMI
57 bool
58 default y
59
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60source "init/Kconfig"
61
62menu "Processor type and features"
63
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64config SMP
65 bool "Symmetric multi-processing support"
66 ---help---
67 This enables support for systems with more than one CPU. If you have
68 a system with only one CPU, like most personal computers, say N. If
69 you have a system with more than one CPU, say Y.
70
71 If you say N here, the kernel will run on single and multiprocessor
72 machines, but will use only one CPU of a multiprocessor machine. If
73 you say Y here, the kernel will run on many, but not all,
74 singleprocessor machines. On a singleprocessor machine, the kernel
75 will run faster if you say N here.
76
77 Note that if you say Y here and choose architecture "586" or
78 "Pentium" under "Processor family", the kernel will not work on 486
79 architectures. Similarly, multiprocessor kernels for the "PPro"
80 architecture may not work on all Pentium based boards.
81
82 People using multiprocessor machines who say Y here should also say
83 Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
84 Management" code will be disabled if you say Y here.
85
86 See also the <file:Documentation/smp.txt>,
87 <file:Documentation/i386/IO-APIC.txt>,
88 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
89 <http://www.tldp.org/docs.html#howto>.
90
91 If you don't know what to do here, say N.
92
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93choice
94 prompt "Subarchitecture Type"
95 default X86_PC
96
97config X86_PC
98 bool "PC-compatible"
99 help
100 Choose this option if your computer is a standard PC or compatible.
101
102config X86_ELAN
103 bool "AMD Elan"
104 help
105 Select this for an AMD Elan processor.
106
107 Do not use this option for K6/Athlon/Opteron processors!
108
109 If unsure, choose "PC-compatible" instead.
110
111config X86_VOYAGER
112 bool "Voyager (NCR)"
113 help
114 Voyager is an MCA-based 32-way capable SMP architecture proprietary
115 to NCR Corp. Machine classes 345x/35xx/4100/51xx are Voyager-based.
116
117 *** WARNING ***
118
119 If you do not specifically know you have a Voyager based machine,
120 say N here, otherwise the kernel you build will not be bootable.
121
122config X86_NUMAQ
123 bool "NUMAQ (IBM/Sequent)"
905c3995 124 select SMP
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125 select NUMA
126 help
127 This option is used for getting Linux to run on a (IBM/Sequent) NUMA
128 multiquad box. This changes the way that processors are bootstrapped,
129 and uses Clustered Logical APIC addressing mode instead of Flat Logical.
130 You will need a new lynxer.elf file to flash your firmware with - send
131 email to <Martin.Bligh@us.ibm.com>.
132
133config X86_SUMMIT
134 bool "Summit/EXA (IBM x440)"
135 depends on SMP
136 help
137 This option is needed for IBM systems that use the Summit/EXA chipset.
138 In particular, it is needed for the x440.
139
140 If you don't have one of these computers, you should say N here.
141
142config X86_BIGSMP
143 bool "Support for other sub-arch SMP systems with more than 8 CPUs"
144 depends on SMP
145 help
146 This option is needed for the systems that have more than 8 CPUs
147 and if the system is not of any sub-arch type above.
148
149 If you don't have such a system, you should say N here.
150
151config X86_VISWS
152 bool "SGI 320/540 (Visual Workstation)"
153 help
154 The SGI Visual Workstation series is an IA32-based workstation
155 based on SGI systems chips with some legacy PC hardware attached.
156
157 Say Y here to create a kernel to run on the SGI 320 or 540.
158
159 A kernel compiled for the Visual Workstation will not run on PCs
160 and vice versa. See <file:Documentation/sgi-visws.txt> for details.
161
162config X86_GENERICARCH
163 bool "Generic architecture (Summit, bigsmp, ES7000, default)"
164 depends on SMP
165 help
166 This option compiles in the Summit, bigsmp, ES7000, default subarchitectures.
167 It is intended for a generic binary kernel.
168
169config X86_ES7000
170 bool "Support for Unisys ES7000 IA32 series"
171 depends on SMP
172 help
173 Support for Unisys ES7000 systems. Say 'Y' here if this kernel is
174 supposed to run on an IA32-based Unisys ES7000 system.
175 Only choose this option if you have such a system, otherwise you
176 should say N here.
177
178endchoice
179
180config ACPI_SRAT
181 bool
182 default y
55910b28 183 depends on ACPI && NUMA && (X86_SUMMIT || X86_GENERICARCH)
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184 select ACPI_NUMA
185
186config HAVE_ARCH_PARSE_SRAT
187 bool
188 default y
189 depends on ACPI_SRAT
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190
191config X86_SUMMIT_NUMA
192 bool
193 default y
194 depends on NUMA && (X86_SUMMIT || X86_GENERICARCH)
195
196config X86_CYCLONE_TIMER
197 bool
198 default y
199 depends on X86_SUMMIT || X86_GENERICARCH
200
201config ES7000_CLUSTERED_APIC
202 bool
203 default y
204 depends on SMP && X86_ES7000 && MPENTIUMIII
205
96d55b88 206source "arch/i386/Kconfig.cpu"
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207
208config HPET_TIMER
209 bool "HPET Timer Support"
210 help
211 This enables the use of the HPET for the kernel's internal timer.
212 HPET is the next generation timer replacing legacy 8254s.
213 You can safely choose Y here. However, HPET will only be
214 activated if the platform and the BIOS support this feature.
215 Otherwise the 8254 will be used for timing services.
216
217 Choose N to continue using the legacy 8254 timer.
218
219config HPET_EMULATE_RTC
c91096d8 220 bool
1da177e4 221 depends on HPET_TIMER && RTC=y
c91096d8 222 default y
1da177e4 223
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224config NR_CPUS
225 int "Maximum number of CPUs (2-255)"
226 range 2 255
227 depends on SMP
228 default "32" if X86_NUMAQ || X86_SUMMIT || X86_BIGSMP || X86_ES7000
229 default "8"
230 help
231 This allows you to specify the maximum number of CPUs which this
232 kernel will support. The maximum supported value is 255 and the
233 minimum value which makes sense is 2.
234
235 This is purely to save memory - each supported CPU adds
236 approximately eight kilobytes to the kernel image.
237
238config SCHED_SMT
239 bool "SMT (Hyperthreading) scheduler support"
96c52749 240 depends on X86_HT
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241 help
242 SMT scheduler support improves the CPU scheduler's decision making
243 when dealing with Intel Pentium 4 chips with HyperThreading at a
244 cost of slightly increased overhead in some places. If unsure say
245 N here.
246
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247config SCHED_MC
248 bool "Multi-core scheduler support"
96c52749 249 depends on X86_HT
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250 default y
251 help
252 Multi-core scheduler support improves the CPU scheduler's decision
253 making when dealing with multi-core CPU chips at a cost of slightly
254 increased overhead in some places. If unsure say N here.
255
cc19ca86 256source "kernel/Kconfig.preempt"
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257
258config X86_UP_APIC
259 bool "Local APIC support on uniprocessors"
260 depends on !SMP && !(X86_VISWS || X86_VOYAGER)
261 help
262 A local APIC (Advanced Programmable Interrupt Controller) is an
263 integrated interrupt controller in the CPU. If you have a single-CPU
264 system which has a processor with a local APIC, you can say Y here to
265 enable and use it. If you say Y here even though your machine doesn't
266 have a local APIC, then the kernel will still run with no slowdown at
267 all. The local APIC supports CPU-generated self-interrupts (timer,
268 performance counters), and the NMI watchdog which detects hard
269 lockups.
270
271config X86_UP_IOAPIC
272 bool "IO-APIC support on uniprocessors"
273 depends on X86_UP_APIC
274 help
275 An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an
276 SMP-capable replacement for PC-style interrupt controllers. Most
277 SMP systems and many recent uniprocessor systems have one.
278
279 If you have a single-CPU system with an IO-APIC, you can say Y here
280 to use it. If you say Y here even though your machine doesn't have
281 an IO-APIC, then the kernel will still run with no slowdown at all.
282
283config X86_LOCAL_APIC
284 bool
285 depends on X86_UP_APIC || ((X86_VISWS || SMP) && !X86_VOYAGER)
286 default y
287
288config X86_IO_APIC
289 bool
290 depends on X86_UP_IOAPIC || (SMP && !(X86_VISWS || X86_VOYAGER))
291 default y
292
293config X86_VISWS_APIC
294 bool
295 depends on X86_VISWS
296 default y
297
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298config X86_MCE
299 bool "Machine Check Exception"
300 depends on !X86_VOYAGER
301 ---help---
302 Machine Check Exception support allows the processor to notify the
303 kernel if it detects a problem (e.g. overheating, component failure).
304 The action the kernel takes depends on the severity of the problem,
305 ranging from a warning message on the console, to halting the machine.
306 Your processor must be a Pentium or newer to support this - check the
307 flags in /proc/cpuinfo for mce. Note that some older Pentium systems
308 have a design flaw which leads to false MCE events - hence MCE is
309 disabled on all P5 processors, unless explicitly enabled with "mce"
310 as a boot argument. Similarly, if MCE is built in and creates a
311 problem on some new non-standard machine, you can boot with "nomce"
312 to disable it. MCE support simply ignores non-MCE processors like
313 the 386 and 486, so nearly everyone can say Y here.
314
315config X86_MCE_NONFATAL
316 tristate "Check for non-fatal errors on AMD Athlon/Duron / Intel Pentium 4"
317 depends on X86_MCE
318 help
319 Enabling this feature starts a timer that triggers every 5 seconds which
320 will look at the machine check registers to see if anything happened.
321 Non-fatal problems automatically get corrected (but still logged).
322 Disable this if you don't want to see these messages.
323 Seeing the messages this option prints out may be indicative of dying hardware,
324 or out-of-spec (ie, overclocked) hardware.
325 This option only does something on certain CPUs.
326 (AMD Athlon/Duron and Intel Pentium 4)
327
328config X86_MCE_P4THERMAL
329 bool "check for P4 thermal throttling interrupt."
330 depends on X86_MCE && (X86_UP_APIC || SMP) && !X86_VISWS
331 help
332 Enabling this feature will cause a message to be printed when the P4
333 enters thermal throttling.
334
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335config VM86
336 default y
337 bool "Enable VM86 support" if EMBEDDED
338 help
339 This option is required by programs like DOSEMU to run 16-bit legacy
340 code on X86 processors. It also may be needed by software like
341 XFree86 to initialize some video cards via BIOS. Disabling this
342 option saves about 6k.
343
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344config TOSHIBA
345 tristate "Toshiba Laptop support"
346 ---help---
347 This adds a driver to safely access the System Management Mode of
348 the CPU on Toshiba portables with a genuine Toshiba BIOS. It does
349 not work on models with a Phoenix BIOS. The System Management Mode
350 is used to set the BIOS and power saving options on Toshiba portables.
351
352 For information on utilities to make use of this driver see the
353 Toshiba Linux utilities web site at:
354 <http://www.buzzard.org.uk/toshiba/>.
355
356 Say Y if you intend to run this kernel on a Toshiba portable.
357 Say N otherwise.
358
359config I8K
360 tristate "Dell laptop support"
361 ---help---
362 This adds a driver to safely access the System Management Mode
363 of the CPU on the Dell Inspiron 8000. The System Management Mode
364 is used to read cpu temperature and cooling fan status and to
365 control the fans on the I8K portables.
366
367 This driver has been tested only on the Inspiron 8000 but it may
368 also work with other Dell laptops. You can force loading on other
369 models by passing the parameter `force=1' to the module. Use at
370 your own risk.
371
372 For information on utilities to make use of this driver see the
373 I8K Linux utilities web site at:
374 <http://people.debian.org/~dz/i8k/>
375
376 Say Y if you intend to run this kernel on a Dell Inspiron 8000.
377 Say N otherwise.
378
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379config X86_REBOOTFIXUPS
380 bool "Enable X86 board specific fixups for reboot"
381 depends on X86
382 default n
383 ---help---
384 This enables chipset and/or board specific fixups to be done
385 in order to get reboot to work correctly. This is only needed on
386 some combinations of hardware and BIOS. The symptom, for which
387 this config is intended, is when reboot ends with a stalled/hung
388 system.
389
390 Currently, the only fixup is for the Geode GX1/CS5530A/TROM2.1.
391 combination.
392
393 Say Y if you want to enable the fixup. Currently, it's safe to
394 enable this option even if you don't need it.
395 Say N otherwise.
396
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397config MICROCODE
398 tristate "/dev/cpu/microcode - Intel IA32 CPU microcode support"
399 ---help---
400 If you say Y here and also to "/dev file system support" in the
401 'File systems' section, you will be able to update the microcode on
402 Intel processors in the IA32 family, e.g. Pentium Pro, Pentium II,
403 Pentium III, Pentium 4, Xeon etc. You will obviously need the
404 actual microcode binary data itself which is not shipped with the
405 Linux kernel.
406
407 For latest news and information on obtaining all the required
408 ingredients for this driver, check:
409 <http://www.urbanmyth.org/microcode/>.
410
411 To compile this driver as a module, choose M here: the
412 module will be called microcode.
413
414config X86_MSR
415 tristate "/dev/cpu/*/msr - Model-specific register support"
416 help
417 This device gives privileged processes access to the x86
418 Model-Specific Registers (MSRs). It is a character device with
419 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
420 MSR accesses are directed to a specific CPU on multi-processor
421 systems.
422
423config X86_CPUID
424 tristate "/dev/cpu/*/cpuid - CPU information support"
425 help
426 This device gives processes access to the x86 CPUID instruction to
427 be executed on a specific processor. It is a character device
428 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
429 /dev/cpu/31/cpuid.
430
431source "drivers/firmware/Kconfig"
432
433choice
434 prompt "High Memory Support"
435 default NOHIGHMEM
436
437config NOHIGHMEM
438 bool "off"
905c3995 439 depends on !X86_NUMAQ
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440 ---help---
441 Linux can use up to 64 Gigabytes of physical memory on x86 systems.
442 However, the address space of 32-bit x86 processors is only 4
443 Gigabytes large. That means that, if you have a large amount of
444 physical memory, not all of it can be "permanently mapped" by the
445 kernel. The physical memory that's not permanently mapped is called
446 "high memory".
447
448 If you are compiling a kernel which will never run on a machine with
449 more than 1 Gigabyte total physical RAM, answer "off" here (default
450 choice and suitable for most users). This will result in a "3GB/1GB"
451 split: 3GB are mapped so that each process sees a 3GB virtual memory
452 space and the remaining part of the 4GB virtual memory space is used
453 by the kernel to permanently map as much physical memory as
454 possible.
455
456 If the machine has between 1 and 4 Gigabytes physical RAM, then
457 answer "4GB" here.
458
459 If more than 4 Gigabytes is used then answer "64GB" here. This
460 selection turns Intel PAE (Physical Address Extension) mode on.
461 PAE implements 3-level paging on IA32 processors. PAE is fully
462 supported by Linux, PAE mode is implemented on all recent Intel
463 processors (Pentium Pro and better). NOTE: If you say "64GB" here,
464 then the kernel will not boot on CPUs that don't support PAE!
465
466 The actual amount of total physical memory will either be
467 auto detected or can be forced by using a kernel command line option
468 such as "mem=256M". (Try "man bootparam" or see the documentation of
469 your boot loader (lilo or loadlin) about how to pass options to the
470 kernel at boot time.)
471
472 If unsure, say "off".
473
474config HIGHMEM4G
475 bool "4GB"
905c3995 476 depends on !X86_NUMAQ
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477 help
478 Select this if you have a 32-bit processor and between 1 and 4
479 gigabytes of physical RAM.
480
481config HIGHMEM64G
482 bool "64GB"
4be68a78 483 depends on X86_CMPXCHG64
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484 help
485 Select this if you have a 32-bit processor and more than 4
486 gigabytes of physical RAM.
487
488endchoice
489
975b3d3d
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490choice
491 depends on EXPERIMENTAL && !X86_PAE
9539d4e7 492 prompt "Memory split" if EMBEDDED
975b3d3d
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493 default VMSPLIT_3G
494 help
495 Select the desired split between kernel and user memory.
496
497 If the address range available to the kernel is less than the
498 physical memory installed, the remaining memory will be available
499 as "high memory". Accessing high memory is a little more costly
500 than low memory, as it needs to be mapped into the kernel first.
501 Note that increasing the kernel address space limits the range
502 available to user programs, making the address space there
503 tighter. Selecting anything other than the default 3G/1G split
504 will also likely make your kernel incompatible with binary-only
505 kernel modules.
506
507 If you are not absolutely sure what you are doing, leave this
508 option alone!
509
510 config VMSPLIT_3G
511 bool "3G/1G user/kernel split"
512 config VMSPLIT_3G_OPT
513 bool "3G/1G user/kernel split (for full 1G low memory)"
514 config VMSPLIT_2G
515 bool "2G/2G user/kernel split"
516 config VMSPLIT_1G
517 bool "1G/3G user/kernel split"
518endchoice
519
520config PAGE_OFFSET
521 hex
522 default 0xB0000000 if VMSPLIT_3G_OPT
523 default 0x78000000 if VMSPLIT_2G
524 default 0x40000000 if VMSPLIT_1G
525 default 0xC0000000
526
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527config HIGHMEM
528 bool
529 depends on HIGHMEM64G || HIGHMEM4G
530 default y
531
532config X86_PAE
533 bool
534 depends on HIGHMEM64G
535 default y
6550e07f 536 select RESOURCES_64BIT
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537
538# Common NUMA Features
539config NUMA
540 bool "Numa Memory Allocation and Scheduler Support"
541 depends on SMP && HIGHMEM64G && (X86_NUMAQ || X86_GENERICARCH || (X86_SUMMIT && ACPI))
542 default n if X86_PC
543 default y if (X86_NUMAQ || X86_SUMMIT)
544
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545comment "NUMA (Summit) requires SMP, 64GB highmem support, ACPI"
546 depends on X86_SUMMIT && (!HIGHMEM64G || !ACPI)
547
c80d79d7
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548config NODES_SHIFT
549 int
550 default "4" if X86_NUMAQ
551 default "3"
552 depends on NEED_MULTIPLE_NODES
553
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554config HAVE_ARCH_BOOTMEM_NODE
555 bool
556 depends on NUMA
557 default y
558
af705362 559config ARCH_HAVE_MEMORY_PRESENT
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560 bool
561 depends on DISCONTIGMEM
562 default y
563
564config NEED_NODE_MEMMAP_SIZE
565 bool
05b79bdc 566 depends on DISCONTIGMEM || SPARSEMEM
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567 default y
568
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569config HAVE_ARCH_ALLOC_REMAP
570 bool
571 depends on NUMA
572 default y
573
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574config ARCH_FLATMEM_ENABLE
575 def_bool y
576 depends on (ARCH_SELECT_MEMORY_MODEL && X86_PC)
577
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578config ARCH_DISCONTIGMEM_ENABLE
579 def_bool y
580 depends on NUMA
581
582config ARCH_DISCONTIGMEM_DEFAULT
583 def_bool y
584 depends on NUMA
585
586config ARCH_SPARSEMEM_ENABLE
587 def_bool y
215c3409
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588 depends on (NUMA || (X86_PC && EXPERIMENTAL))
589 select SPARSEMEM_STATIC
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590
591config ARCH_SELECT_MEMORY_MODEL
592 def_bool y
593 depends on ARCH_SPARSEMEM_ENABLE
594
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595source "mm/Kconfig"
596
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597config HAVE_ARCH_EARLY_PFN_TO_NID
598 bool
599 default y
d41dee36 600 depends on NUMA
b159d43f 601
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602config HIGHPTE
603 bool "Allocate 3rd-level pagetables from highmem"
604 depends on HIGHMEM4G || HIGHMEM64G
605 help
606 The VM uses one page table entry for each page of physical memory.
607 For systems with a lot of RAM, this can be wasteful of precious
608 low memory. Setting this option will put user-space page table
609 entries in high memory.
610
611config MATH_EMULATION
612 bool "Math emulation"
613 ---help---
614 Linux can emulate a math coprocessor (used for floating point
615 operations) if you don't have one. 486DX and Pentium processors have
616 a math coprocessor built in, 486SX and 386 do not, unless you added
617 a 487DX or 387, respectively. (The messages during boot time can
618 give you some hints here ["man dmesg"].) Everyone needs either a
619 coprocessor or this emulation.
620
621 If you don't have a math coprocessor, you need to say Y here; if you
622 say Y here even though you have a coprocessor, the coprocessor will
623 be used nevertheless. (This behavior can be changed with the kernel
624 command line option "no387", which comes handy if your coprocessor
625 is broken. Try "man bootparam" or see the documentation of your boot
626 loader (lilo or loadlin) about how to pass options to the kernel at
627 boot time.) This means that it is a good idea to say Y here if you
628 intend to use this kernel on different machines.
629
630 More information about the internals of the Linux math coprocessor
631 emulation can be found in <file:arch/i386/math-emu/README>.
632
633 If you are not sure, say Y; apart from resulting in a 66 KB bigger
634 kernel, it won't hurt.
635
636config MTRR
637 bool "MTRR (Memory Type Range Register) support"
638 ---help---
639 On Intel P6 family processors (Pentium Pro, Pentium II and later)
640 the Memory Type Range Registers (MTRRs) may be used to control
641 processor access to memory ranges. This is most useful if you have
642 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
643 allows bus write transfers to be combined into a larger transfer
644 before bursting over the PCI/AGP bus. This can increase performance
645 of image write operations 2.5 times or more. Saying Y here creates a
646 /proc/mtrr file which may be used to manipulate your processor's
647 MTRRs. Typically the X server should use this.
648
649 This code has a reasonably generic interface so that similar
650 control registers on other processors can be easily supported
651 as well:
652
653 The Cyrix 6x86, 6x86MX and M II processors have Address Range
654 Registers (ARRs) which provide a similar functionality to MTRRs. For
655 these, the ARRs are used to emulate the MTRRs.
656 The AMD K6-2 (stepping 8 and above) and K6-3 processors have two
657 MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing
658 write-combining. All of these processors are supported by this code
659 and it makes sense to say Y here if you have one of them.
660
661 Saying Y here also fixes a problem with buggy SMP BIOSes which only
662 set the MTRRs for the boot CPU and not for the secondary CPUs. This
663 can lead to all sorts of problems, so it's good to say Y here.
664
665 You can safely say Y even if your machine doesn't have MTRRs, you'll
666 just add about 9 KB to your kernel.
667
668 See <file:Documentation/mtrr.txt> for more information.
669
670config EFI
671 bool "Boot from EFI support (EXPERIMENTAL)"
672 depends on ACPI
673 default n
674 ---help---
675 This enables the the kernel to boot on EFI platforms using
676 system configuration information passed to it from the firmware.
677 This also enables the kernel to use any EFI runtime services that are
678 available (such as the EFI variable services).
679
680 This option is only useful on systems that have EFI firmware
681 and will result in a kernel image that is ~8k larger. In addition,
682 you must use the latest ELILO loader available at
683 <http://elilo.sourceforge.net> in order to take advantage of
684 kernel initialization using EFI information (neither GRUB nor LILO know
685 anything about EFI). However, even with this option, the resultant
686 kernel should continue to boot on existing non-EFI platforms.
687
688config IRQBALANCE
689 bool "Enable kernel irq balancing"
690 depends on SMP && X86_IO_APIC
691 default y
692 help
693 The default yes will allow the kernel to do irq load balancing.
694 Saying no will keep the kernel from doing irq load balancing.
695
1da177e4
LT
696# turning this on wastes a bunch of space.
697# Summit needs it only when NUMA is on
698config BOOT_IOREMAP
699 bool
700 depends on (((X86_SUMMIT || X86_GENERICARCH) && NUMA) || (X86 && EFI))
701 default y
702
703config REGPARM
69ef4141 704 bool "Use register arguments"
b824eb60 705 default y
1da177e4 706 help
b824eb60
IM
707 Compile the kernel with -mregparm=3. This instructs gcc to use
708 a more efficient function call ABI which passes the first three
709 arguments of a function call via registers, which results in denser
710 and faster code.
711
712 If this option is disabled, then the default ABI of passing
713 arguments via the stack is used.
714
715 If unsure, say Y.
1da177e4 716
1da177e4
LT
717config SECCOMP
718 bool "Enable seccomp to safely compute untrusted bytecode"
719 depends on PROC_FS
720 default y
721 help
722 This kernel feature is useful for number crunching applications
723 that may need to compute untrusted bytecode during their
724 execution. By using pipes or other transports made available to
725 the process as file descriptors supporting the read/write
726 syscalls, it's possible to isolate those applications in
727 their own address space using seccomp. Once seccomp is
728 enabled via /proc/<pid>/seccomp, it cannot be disabled
729 and the task is only allowed to execute a few safe syscalls
730 defined by each seccomp mode.
731
732 If unsure, say Y. Only embedded should say N here.
733
59121003
CL
734source kernel/Kconfig.hz
735
5033cba0
EB
736config KEXEC
737 bool "kexec system call (EXPERIMENTAL)"
738 depends on EXPERIMENTAL
739 help
740 kexec is a system call that implements the ability to shutdown your
741 current kernel, and to start another kernel. It is like a reboot
48a1204c 742 but it is independent of the system firmware. And like a reboot
5033cba0
EB
743 you can start any kernel with it, not just Linux.
744
1f1332f7 745 The name comes from the similarity to the exec system call.
5033cba0
EB
746
747 It is an ongoing process to be certain the hardware in a machine
748 is properly shutdown, so do not be surprised if this code does not
749 initially work for you. It may help to enable device hotplugging
750 support. As of this writing the exact hardware interface is
751 strongly in flux, so no good recommendation can be made.
752
5f016456
VG
753config CRASH_DUMP
754 bool "kernel crash dumps (EXPERIMENTAL)"
5f016456
VG
755 depends on EXPERIMENTAL
756 depends on HIGHMEM
757 help
758 Generate crash dump after being started by kexec.
05970d47
MS
759
760config PHYSICAL_START
761 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
762
763 default "0x1000000" if CRASH_DUMP
764 default "0x100000"
765 help
766 This gives the physical address where the kernel is loaded. Normally
767 for regular kernels this value is 0x100000 (1MB). But in the case
768 of kexec on panic the fail safe kernel needs to run at a different
769 address than the panic-ed kernel. This option is used to set the load
770 address for kernels used to capture crash dump on being kexec'ed
771 after panic. The default value for crash dump kernels is
772 0x1000000 (16MB). This can also be set based on the "X" value as
773 specified in the "crashkernel=YM@XM" command line boot parameter
774 passed to the panic-ed kernel. Typically this parameter is set as
775 crashkernel=64M@16M. Please take a look at
776 Documentation/kdump/kdump.txt for more details about crash dumps.
777
778 Don't change this unless you know what you are doing.
779
ce63ad78
RD
780config HOTPLUG_CPU
781 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
35076bdf 782 depends on SMP && HOTPLUG && EXPERIMENTAL && !X86_VOYAGER
ce63ad78 783 ---help---
b2d596d8
PM
784 Say Y here to experiment with turning CPUs off and on, and to
785 enable suspend on SMP systems. CPUs can be controlled through
786 /sys/devices/system/cpu.
ce63ad78 787
e6e5494c
IM
788config COMPAT_VDSO
789 bool "Compat VDSO support"
790 default y
791 help
792 Map the VDSO to the predictable old-style address too.
793 ---help---
794 Say N here if you are running a sufficiently recent glibc
795 version (2.3.3 or later), to remove the high-mapped
796 VDSO mapping and to exclusively use the randomized VDSO.
797
798 If unsure, say Y.
ce63ad78 799
1da177e4
LT
800endmenu
801
cc57637b
YG
802config ARCH_ENABLE_MEMORY_HOTPLUG
803 def_bool y
804 depends on HIGHMEM
1da177e4
LT
805
806menu "Power management options (ACPI, APM)"
807 depends on !X86_VOYAGER
808
809source kernel/power/Kconfig
810
811source "drivers/acpi/Kconfig"
812
813menu "APM (Advanced Power Management) BIOS Support"
814depends on PM && !X86_VISWS
815
816config APM
817 tristate "APM (Advanced Power Management) BIOS support"
987d4613 818 depends on PM
1da177e4
LT
819 ---help---
820 APM is a BIOS specification for saving power using several different
821 techniques. This is mostly useful for battery powered laptops with
822 APM compliant BIOSes. If you say Y here, the system time will be
823 reset after a RESUME operation, the /proc/apm device will provide
824 battery status information, and user-space programs will receive
825 notification of APM "events" (e.g. battery status change).
826
827 If you select "Y" here, you can disable actual use of the APM
828 BIOS by passing the "apm=off" option to the kernel at boot time.
829
830 Note that the APM support is almost completely disabled for
831 machines with more than one CPU.
832
833 In order to use APM, you will need supporting software. For location
834 and more information, read <file:Documentation/pm.txt> and the
835 Battery Powered Linux mini-HOWTO, available from
836 <http://www.tldp.org/docs.html#howto>.
837
838 This driver does not spin down disk drives (see the hdparm(8)
839 manpage ("man 8 hdparm") for that), and it doesn't turn off
840 VESA-compliant "green" monitors.
841
842 This driver does not support the TI 4000M TravelMate and the ACER
843 486/DX4/75 because they don't have compliant BIOSes. Many "green"
844 desktop machines also don't have compliant BIOSes, and this driver
845 may cause those machines to panic during the boot phase.
846
847 Generally, if you don't have a battery in your machine, there isn't
848 much point in using this driver and you should say N. If you get
849 random kernel OOPSes or reboots that don't seem to be related to
850 anything, try disabling/enabling this option (or disabling/enabling
851 APM in your BIOS).
852
853 Some other things you should try when experiencing seemingly random,
854 "weird" problems:
855
856 1) make sure that you have enough swap space and that it is
857 enabled.
858 2) pass the "no-hlt" option to the kernel
859 3) switch on floating point emulation in the kernel and pass
860 the "no387" option to the kernel
861 4) pass the "floppy=nodma" option to the kernel
862 5) pass the "mem=4M" option to the kernel (thereby disabling
863 all but the first 4 MB of RAM)
864 6) make sure that the CPU is not over clocked.
865 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/>
866 8) disable the cache from your BIOS settings
867 9) install a fan for the video card or exchange video RAM
868 10) install a better fan for the CPU
869 11) exchange RAM chips
870 12) exchange the motherboard.
871
872 To compile this driver as a module, choose M here: the
873 module will be called apm.
874
875config APM_IGNORE_USER_SUSPEND
876 bool "Ignore USER SUSPEND"
877 depends on APM
878 help
879 This option will ignore USER SUSPEND requests. On machines with a
880 compliant APM BIOS, you want to say N. However, on the NEC Versa M
881 series notebooks, it is necessary to say Y because of a BIOS bug.
882
883config APM_DO_ENABLE
884 bool "Enable PM at boot time"
885 depends on APM
886 ---help---
887 Enable APM features at boot time. From page 36 of the APM BIOS
888 specification: "When disabled, the APM BIOS does not automatically
889 power manage devices, enter the Standby State, enter the Suspend
890 State, or take power saving steps in response to CPU Idle calls."
891 This driver will make CPU Idle calls when Linux is idle (unless this
892 feature is turned off -- see "Do CPU IDLE calls", below). This
893 should always save battery power, but more complicated APM features
894 will be dependent on your BIOS implementation. You may need to turn
895 this option off if your computer hangs at boot time when using APM
896 support, or if it beeps continuously instead of suspending. Turn
897 this off if you have a NEC UltraLite Versa 33/C or a Toshiba
898 T400CDT. This is off by default since most machines do fine without
899 this feature.
900
901config APM_CPU_IDLE
902 bool "Make CPU Idle calls when idle"
903 depends on APM
904 help
905 Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop.
906 On some machines, this can activate improved power savings, such as
907 a slowed CPU clock rate, when the machine is idle. These idle calls
908 are made after the idle loop has run for some length of time (e.g.,
909 333 mS). On some machines, this will cause a hang at boot time or
910 whenever the CPU becomes idle. (On machines with more than one CPU,
911 this option does nothing.)
912
913config APM_DISPLAY_BLANK
914 bool "Enable console blanking using APM"
915 depends on APM
916 help
917 Enable console blanking using the APM. Some laptops can use this to
918 turn off the LCD backlight when the screen blanker of the Linux
919 virtual console blanks the screen. Note that this is only used by
920 the virtual console screen blanker, and won't turn off the backlight
921 when using the X Window system. This also doesn't have anything to
922 do with your VESA-compliant power-saving monitor. Further, this
923 option doesn't work for all laptops -- it might not turn off your
924 backlight at all, or it might print a lot of errors to the console,
925 especially if you are using gpm.
926
927config APM_RTC_IS_GMT
928 bool "RTC stores time in GMT"
929 depends on APM
930 help
931 Say Y here if your RTC (Real Time Clock a.k.a. hardware clock)
932 stores the time in GMT (Greenwich Mean Time). Say N if your RTC
933 stores localtime.
934
935 It is in fact recommended to store GMT in your RTC, because then you
936 don't have to worry about daylight savings time changes. The only
937 reason not to use GMT in your RTC is if you also run a broken OS
938 that doesn't understand GMT.
939
940config APM_ALLOW_INTS
941 bool "Allow interrupts during APM BIOS calls"
942 depends on APM
943 help
944 Normally we disable external interrupts while we are making calls to
945 the APM BIOS as a measure to lessen the effects of a badly behaving
946 BIOS implementation. The BIOS should reenable interrupts if it
947 needs to. Unfortunately, some BIOSes do not -- especially those in
948 many of the newer IBM Thinkpads. If you experience hangs when you
949 suspend, try setting this to Y. Otherwise, say N.
950
951config APM_REAL_MODE_POWER_OFF
952 bool "Use real mode APM BIOS call to power off"
953 depends on APM
954 help
955 Use real mode APM BIOS calls to switch off the computer. This is
956 a work-around for a number of buggy BIOSes. Switch this option on if
957 your computer crashes instead of powering off properly.
958
959endmenu
960
961source "arch/i386/kernel/cpu/cpufreq/Kconfig"
962
963endmenu
964
965menu "Bus options (PCI, PCMCIA, EISA, MCA, ISA)"
966
967config PCI
968 bool "PCI support" if !X86_VISWS
969 depends on !X86_VOYAGER
970 default y if X86_VISWS
971 help
972 Find out whether you have a PCI motherboard. PCI is the name of a
973 bus system, i.e. the way the CPU talks to the other stuff inside
974 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
975 VESA. If you have PCI, say Y, otherwise N.
976
977 The PCI-HOWTO, available from
978 <http://www.tldp.org/docs.html#howto>, contains valuable
979 information about which PCI hardware does work under Linux and which
980 doesn't.
981
982choice
983 prompt "PCI access mode"
984 depends on PCI && !X86_VISWS
985 default PCI_GOANY
986 ---help---
987 On PCI systems, the BIOS can be used to detect the PCI devices and
988 determine their configuration. However, some old PCI motherboards
989 have BIOS bugs and may crash if this is done. Also, some embedded
990 PCI-based systems don't have any BIOS at all. Linux can also try to
991 detect the PCI hardware directly without using the BIOS.
992
993 With this option, you can specify how Linux should detect the
994 PCI devices. If you choose "BIOS", the BIOS will be used,
995 if you choose "Direct", the BIOS won't be used, and if you
996 choose "MMConfig", then PCI Express MMCONFIG will be used.
997 If you choose "Any", the kernel will try MMCONFIG, then the
998 direct access method and falls back to the BIOS if that doesn't
999 work. If unsure, go with the default, which is "Any".
1000
1001config PCI_GOBIOS
1002 bool "BIOS"
1003
1004config PCI_GOMMCONFIG
1005 bool "MMConfig"
1006
1007config PCI_GODIRECT
1008 bool "Direct"
1009
1010config PCI_GOANY
1011 bool "Any"
1012
1013endchoice
1014
1015config PCI_BIOS
1016 bool
1017 depends on !X86_VISWS && PCI && (PCI_GOBIOS || PCI_GOANY)
1018 default y
1019
1020config PCI_DIRECT
1021 bool
1022 depends on PCI && ((PCI_GODIRECT || PCI_GOANY) || X86_VISWS)
1023 default y
1024
1025config PCI_MMCONFIG
1026 bool
8aadff7d 1027 depends on PCI && ACPI && (PCI_GOMMCONFIG || PCI_GOANY)
1da177e4
LT
1028 default y
1029
1030source "drivers/pci/pcie/Kconfig"
1031
1032source "drivers/pci/Kconfig"
1033
5cae841b
AV
1034config ISA_DMA_API
1035 bool
1036 default y
1037
1da177e4
LT
1038config ISA
1039 bool "ISA support"
1040 depends on !(X86_VOYAGER || X86_VISWS)
1041 help
1042 Find out whether you have ISA slots on your motherboard. ISA is the
1043 name of a bus system, i.e. the way the CPU talks to the other stuff
1044 inside your box. Other bus systems are PCI, EISA, MicroChannel
1045 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1046 newer boards don't support it. If you have ISA, say Y, otherwise N.
1047
1048config EISA
1049 bool "EISA support"
1050 depends on ISA
1051 ---help---
1052 The Extended Industry Standard Architecture (EISA) bus was
1053 developed as an open alternative to the IBM MicroChannel bus.
1054
1055 The EISA bus provided some of the features of the IBM MicroChannel
1056 bus while maintaining backward compatibility with cards made for
1057 the older ISA bus. The EISA bus saw limited use between 1988 and
1058 1995 when it was made obsolete by the PCI bus.
1059
1060 Say Y here if you are building a kernel for an EISA-based machine.
1061
1062 Otherwise, say N.
1063
1064source "drivers/eisa/Kconfig"
1065
1066config MCA
1067 bool "MCA support" if !(X86_VISWS || X86_VOYAGER)
1068 default y if X86_VOYAGER
1069 help
1070 MicroChannel Architecture is found in some IBM PS/2 machines and
1071 laptops. It is a bus system similar to PCI or ISA. See
1072 <file:Documentation/mca.txt> (and especially the web page given
1073 there) before attempting to build an MCA bus kernel.
1074
1075source "drivers/mca/Kconfig"
1076
1077config SCx200
1078 tristate "NatSemi SCx200 support"
1079 depends on !X86_VOYAGER
1080 help
6ae7440e
JC
1081 This provides basic support for National Semiconductor's
1082 (now AMD's) Geode processors. The driver probes for the
1083 PCI-IDs of several on-chip devices, so its a good dependency
1084 for other scx200_* drivers.
1da177e4 1085
6ae7440e 1086 If compiled as a module, the driver is named scx200.
1da177e4 1087
6ae7440e
JC
1088config SCx200HR_TIMER
1089 tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
1090 depends on SCx200 && GENERIC_TIME
1091 default y
1092 help
1093 This driver provides a clocksource built upon the on-chip
1094 27MHz high-resolution timer. Its also a workaround for
1095 NSC Geode SC-1100's buggy TSC, which loses time when the
1096 processor goes idle (as is done by the scheduler). The
1097 other workaround is idle=poll boot option.
1da177e4 1098
a32073bf
AK
1099config K8_NB
1100 def_bool y
1101 depends on AGP_AMD64
1102
1da177e4
LT
1103source "drivers/pcmcia/Kconfig"
1104
1105source "drivers/pci/hotplug/Kconfig"
1106
1107endmenu
1108
1109menu "Executable file formats"
1110
1111source "fs/Kconfig.binfmt"
1112
1113endmenu
1114
d5950b43
SR
1115source "net/Kconfig"
1116
1da177e4
LT
1117source "drivers/Kconfig"
1118
1119source "fs/Kconfig"
1120
cd6b0762
PP
1121menu "Instrumentation Support"
1122 depends on EXPERIMENTAL
1123
1da177e4
LT
1124source "arch/i386/oprofile/Kconfig"
1125
cd6b0762
PP
1126config KPROBES
1127 bool "Kprobes (EXPERIMENTAL)"
add2b6fd 1128 depends on EXPERIMENTAL && MODULES
cd6b0762
PP
1129 help
1130 Kprobes allows you to trap at almost any kernel address and
1131 execute a callback function. register_kprobe() establishes
1132 a probepoint and specifies the callback. Kprobes is useful
1133 for kernel debugging, non-intrusive instrumentation and testing.
1134 If in doubt, say "N".
1135endmenu
1136
1da177e4
LT
1137source "arch/i386/Kconfig.debug"
1138
1139source "security/Kconfig"
1140
1141source "crypto/Kconfig"
1142
1143source "lib/Kconfig"
1144
1145#
1146# Use the generic interrupt handling code in kernel/irq/:
1147#
1148config GENERIC_HARDIRQS
1149 bool
1150 default y
1151
1152config GENERIC_IRQ_PROBE
1153 bool
1154 default y
1155
54d5d424
AR
1156config GENERIC_PENDING_IRQ
1157 bool
1158 depends on GENERIC_HARDIRQS && SMP
1159 default y
1160
1da177e4
LT
1161config X86_SMP
1162 bool
1163 depends on SMP && !X86_VOYAGER
1164 default y
1165
1166config X86_HT
1167 bool
1168 depends on SMP && !(X86_VISWS || X86_VOYAGER)
1169 default y
1170
1171config X86_BIOS_REBOOT
1172 bool
1173 depends on !(X86_VISWS || X86_VOYAGER)
1174 default y
1175
1176config X86_TRAMPOLINE
1177 bool
1178 depends on X86_SMP || (X86_VOYAGER && SMP)
1179 default y
97fc79f9
TG
1180
1181config KTIME_SCALAR
1182 bool
1183 default y
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