2 # For a description of the syntax of this configuration file,
3 # see Documentation/kbuild/kconfig-language.txt.
5 # Note: ISA is disabled and will hopefully never be enabled.
6 # If you managed to buy an ISA x86-64 box you'll have to fix all the
7 # ISA drivers you need yourself.
10 mainmenu "Linux Kernel Configuration"
16 Port to the x86-64 architecture. x86-64 is a 64-bit extension to the
17 classical 32-bit x86 architecture. For details see
18 <http://www.x86-64.org/>.
27 config SEMAPHORE_SLEEPERS
41 config RWSEM_GENERIC_SPINLOCK
45 config RWSEM_XCHGADD_ALGORITHM
48 config GENERIC_HWEIGHT
52 config GENERIC_CALIBRATE_DELAY
64 config GENERIC_ISA_DMA
72 config ARCH_MAY_HAVE_PC_FDC
83 menu "Processor type and features"
86 prompt "Subarchitecture Type"
92 Choose this option if your computer is a standard PC or compatible.
95 bool "Support for ScaleMP vSMP"
97 Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is
98 supposed to run on these EM64T-based machines. Only choose this option
99 if you have one of these machines.
104 prompt "Processor family"
108 bool "AMD-Opteron/Athlon64"
110 Optimize for AMD Opteron/Athlon64/Hammer/K8 CPUs.
115 Optimize for Intel Pentium 4 and Xeon CPUs with Intel
116 Extended Memory 64 Technology(EM64T). For details see
117 <http://www.intel.com/technology/64bitextensions/>.
120 bool "Generic-x86-64"
127 # Define implied options from the CPU selection here
129 config X86_L1_CACHE_BYTES
131 default "128" if GENERIC_CPU || MPSC
134 config X86_L1_CACHE_SHIFT
136 default "7" if GENERIC_CPU || MPSC
148 tristate "/dev/cpu/microcode - Intel CPU microcode support"
150 If you say Y here the 'File systems' section, you will be
151 able to update the microcode on Intel processors. You will
152 obviously need the actual microcode binary data itself which is
153 not shipped with the Linux kernel.
155 For latest news and information on obtaining all the required
156 ingredients for this driver, check:
157 <http://www.urbanmyth.org/microcode/>.
159 To compile this driver as a module, choose M here: the
160 module will be called microcode.
161 If you use modprobe or kmod you may also want to add the line
162 'alias char-major-10-184 microcode' to your /etc/modules.conf file.
165 tristate "/dev/cpu/*/msr - Model-specific register support"
167 This device gives privileged processes access to the x86
168 Model-Specific Registers (MSRs). It is a character device with
169 major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
170 MSR accesses are directed to a specific CPU on multi-processor
174 tristate "/dev/cpu/*/cpuid - CPU information support"
176 This device gives processes access to the x86 CPUID instruction to
177 be executed on a specific processor. It is a character device
178 with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
183 depends on SMP && !MK8
186 config MATH_EMULATION
199 config X86_LOCAL_APIC
204 bool "MTRR (Memory Type Range Register) support"
206 On Intel P6 family processors (Pentium Pro, Pentium II and later)
207 the Memory Type Range Registers (MTRRs) may be used to control
208 processor access to memory ranges. This is most useful if you have
209 a video (VGA) card on a PCI or AGP bus. Enabling write-combining
210 allows bus write transfers to be combined into a larger transfer
211 before bursting over the PCI/AGP bus. This can increase performance
212 of image write operations 2.5 times or more. Saying Y here creates a
213 /proc/mtrr file which may be used to manipulate your processor's
214 MTRRs. Typically the X server should use this.
216 This code has a reasonably generic interface so that similar
217 control registers on other processors can be easily supported
220 Saying Y here also fixes a problem with buggy SMP BIOSes which only
221 set the MTRRs for the boot CPU and not for the secondary CPUs. This
222 can lead to all sorts of problems, so it's good to say Y here.
224 Just say Y here, all x86-64 machines support MTRRs.
226 See <file:Documentation/mtrr.txt> for more information.
229 bool "Symmetric multi-processing support"
231 This enables support for systems with more than one CPU. If you have
232 a system with only one CPU, like most personal computers, say N. If
233 you have a system with more than one CPU, say Y.
235 If you say N here, the kernel will run on single and multiprocessor
236 machines, but will use only one CPU of a multiprocessor machine. If
237 you say Y here, the kernel will run on many, but not all,
238 singleprocessor machines. On a singleprocessor machine, the kernel
239 will run faster if you say N here.
241 If you don't know what to do here, say N.
244 bool "SMT (Hyperthreading) scheduler support"
248 SMT scheduler support improves the CPU scheduler's decision making
249 when dealing with Intel Pentium 4 chips with HyperThreading at a
250 cost of slightly increased overhead in some places. If unsure say
254 bool "Multi-core scheduler support"
258 Multi-core scheduler support improves the CPU scheduler's decision
259 making when dealing with multi-core CPU chips at a cost of slightly
260 increased overhead in some places. If unsure say N here.
262 source "kernel/Kconfig.preempt"
265 bool "Non Uniform Memory Access (NUMA) Support"
268 Enable NUMA (Non Uniform Memory Access) support. The kernel
269 will try to allocate memory used by a CPU on the local memory
270 controller of the CPU and add some more NUMA awareness to the kernel.
271 This code is recommended on all multiprocessor Opteron systems.
272 If the system is EM64T, you should say N unless your system is EM64T
276 bool "Old style AMD Opteron NUMA detection"
280 Enable K8 NUMA node topology detection. You should say Y here if
281 you have a multi processor AMD K8 system. This uses an old
282 method to read the NUMA configurtion directly from the builtin
283 Northbridge of Opteron. It is recommended to use X86_64_ACPI_NUMA
284 instead, which also takes priority if both are compiled in.
286 # Dummy CONFIG option to select ACPI_NUMA from drivers/acpi/Kconfig.
288 config X86_64_ACPI_NUMA
289 bool "ACPI NUMA detection"
295 Enable ACPI SRAT based node topology detection.
298 bool "NUMA emulation"
301 Enable NUMA emulation. A flat machine will be split
302 into virtual nodes when booted with "numa=fake=N", where N is the
303 number of nodes. This is only useful for debugging.
305 config ARCH_DISCONTIGMEM_ENABLE
311 config ARCH_DISCONTIGMEM_ENABLE
315 config ARCH_DISCONTIGMEM_DEFAULT
319 config ARCH_SPARSEMEM_ENABLE
321 depends on (NUMA || EXPERIMENTAL)
323 config ARCH_MEMORY_PROBE
325 depends on MEMORY_HOTPLUG
327 config ARCH_FLATMEM_ENABLE
333 config HAVE_ARCH_EARLY_PFN_TO_NID
338 int "Maximum number of CPUs (2-256)"
343 This allows you to specify the maximum number of CPUs which this
344 kernel will support. Current maximum is 256 CPUs due to
345 APIC addressing limits. Less depending on the hardware.
347 This is purely to save memory - each supported CPU requires
348 memory in the static kernel configuration.
351 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
352 depends on SMP && HOTPLUG && EXPERIMENTAL
354 Say Y here to experiment with turning CPUs off and on. CPUs
355 can be controlled through /sys/devices/system/cpu/cpu#.
356 Say N if you want to disable CPU hotplug.
363 Use the IA-PC HPET (High Precision Event Timer) to manage
364 time in preference to the PIT and RTC, if a HPET is
365 present. The HPET provides a stable time base on SMP
366 systems, unlike the TSC, but it is more expensive to access,
367 as it is off-chip. You can find the HPET spec at
368 <http://www.intel.com/hardwaredesign/hpetspec.htm>.
370 config HPET_EMULATE_RTC
371 bool "Provide RTC interrupt"
372 depends on HPET_TIMER && RTC=y
375 bool "K8 GART IOMMU support"
380 Support for hardware IOMMU in AMD's Opteron/Athlon64 Processors
381 and for the bounce buffering software IOMMU.
382 Needed to run systems with more than 3GB of memory properly with
383 32-bit PCI devices that do not support DAC (Double Address Cycle).
384 The IOMMU can be turned off at runtime with the iommu=off parameter.
385 Normally the kernel will take the right choice by itself.
386 This option includes a driver for the AMD Opteron/Athlon64 IOMMU
387 northbridge and a software emulation used on other systems without
388 hardware IOMMU. If unsure, say Y.
390 # need this always enabled with GART_IOMMU for the VIA workaround
394 depends on GART_IOMMU
397 bool "Machine check support" if EMBEDDED
400 Include a machine check error handler to report hardware errors.
401 This version will require the mcelog utility to decode some
402 machine check error logs. See
403 ftp://ftp.x86-64.org/pub/linux/tools/mcelog
406 bool "Intel MCE features"
407 depends on X86_MCE && X86_LOCAL_APIC
410 Additional support for intel specific MCE features such as
414 bool "AMD MCE features"
415 depends on X86_MCE && X86_LOCAL_APIC
418 Additional support for AMD specific MCE features such as
419 the DRAM Error Threshold.
422 bool "kexec system call (EXPERIMENTAL)"
423 depends on EXPERIMENTAL
425 kexec is a system call that implements the ability to shutdown your
426 current kernel, and to start another kernel. It is like a reboot
427 but it is indepedent of the system firmware. And like a reboot
428 you can start any kernel with it, not just Linux.
430 The name comes from the similiarity to the exec system call.
432 It is an ongoing process to be certain the hardware in a machine
433 is properly shutdown, so do not be surprised if this code does not
434 initially work for you. It may help to enable device hotplugging
435 support. As of this writing the exact hardware interface is
436 strongly in flux, so no good recommendation can be made.
439 bool "kernel crash dumps (EXPERIMENTAL)"
440 depends on EXPERIMENTAL
442 Generate crash dump after being started by kexec.
444 config PHYSICAL_START
445 hex "Physical address where the kernel is loaded" if (EMBEDDED || CRASH_DUMP)
446 default "0x1000000" if CRASH_DUMP
449 This gives the physical address where the kernel is loaded. Normally
450 for regular kernels this value is 0x200000 (2MB). But in the case
451 of kexec on panic the fail safe kernel needs to run at a different
452 address than the panic-ed kernel. This option is used to set the load
453 address for kernels used to capture crash dump on being kexec'ed
454 after panic. The default value for crash dump kernels is
455 0x1000000 (16MB). This can also be set based on the "X" value as
456 specified in the "crashkernel=YM@XM" command line boot parameter
457 passed to the panic-ed kernel. Typically this parameter is set as
458 crashkernel=64M@16M. Please take a look at
459 Documentation/kdump/kdump.txt for more details about crash dumps.
461 Don't change this unless you know what you are doing.
464 bool "Enable seccomp to safely compute untrusted bytecode"
468 This kernel feature is useful for number crunching applications
469 that may need to compute untrusted bytecode during their
470 execution. By using pipes or other transports made available to
471 the process as file descriptors supporting the read/write
472 syscalls, it's possible to isolate those applications in
473 their own address space using seccomp. Once seccomp is
474 enabled via /proc/<pid>/seccomp, it cannot be disabled
475 and the task is only allowed to execute a few safe syscalls
476 defined by each seccomp mode.
478 If unsure, say Y. Only embedded should say N here.
480 source kernel/Kconfig.hz
483 bool "Function reordering"
486 This option enables the toolchain to reorder functions for a more
487 optimal TLB usage. If you have pretty much any version of binutils,
488 this can increase your kernel build time by roughly one minute.
493 # Use the generic interrupt handling code in kernel/irq/:
495 config GENERIC_HARDIRQS
499 config GENERIC_IRQ_PROBE
503 # we have no ISA slots, but we do have ISA-style DMA.
508 config GENERIC_PENDING_IRQ
510 depends on GENERIC_HARDIRQS && SMP
513 menu "Power management options"
515 source kernel/power/Kconfig
517 source "drivers/acpi/Kconfig"
519 source "arch/x86_64/kernel/cpufreq/Kconfig"
523 menu "Bus options (PCI etc.)"
528 # x86-64 doesn't support PCI BIOS access from long mode so always go direct.
535 bool "Support mmconfig PCI config space access"
536 depends on PCI && ACPI
538 source "drivers/pci/pcie/Kconfig"
540 source "drivers/pci/Kconfig"
542 source "drivers/pcmcia/Kconfig"
544 source "drivers/pci/hotplug/Kconfig"
549 menu "Executable file formats / Emulations"
551 source "fs/Kconfig.binfmt"
553 config IA32_EMULATION
554 bool "IA32 Emulation"
556 Include code to run 32-bit programs under a 64-bit kernel. You should likely
557 turn this on, unless you're 100% sure that you don't have any 32-bit programs
561 tristate "IA32 a.out support"
562 depends on IA32_EMULATION
564 Support old a.out binaries in the 32bit emulation.
568 depends on IA32_EMULATION
571 config SYSVIPC_COMPAT
573 depends on COMPAT && SYSVIPC
580 source drivers/Kconfig
582 source "drivers/firmware/Kconfig"
586 menu "Instrumentation Support"
587 depends on EXPERIMENTAL
589 source "arch/x86_64/oprofile/Kconfig"
592 bool "Kprobes (EXPERIMENTAL)"
593 depends on EXPERIMENTAL && MODULES
595 Kprobes allows you to trap at almost any kernel address and
596 execute a callback function. register_kprobe() establishes
597 a probepoint and specifies the callback. Kprobes is useful
598 for kernel debugging, non-intrusive instrumentation and testing.
599 If in doubt, say "N".
602 source "arch/x86_64/Kconfig.debug"
604 source "security/Kconfig"
606 source "crypto/Kconfig"