#
# For a description of the syntax of this configuration file,
# see Documentation/kbuild/kconfig-language.txt.
#
# Note: ISA is disabled and will hopefully never be enabled.
# If you managed to buy an ISA x86-64 box you'll have to fix all the
# ISA drivers you need yourself.
#
mainmenu "Linux Kernel Configuration"
config X86_64
bool
default y
help
Port to the x86-64 architecture. x86-64 is a 64-bit extension to the
classical 32-bit x86 architecture. For details see
<http://www.x86-64.org/>.
config 64BIT
def_bool y
config X86
bool
default y
config MMU
bool
default y
config ISA
bool
config SBUS
bool
config RWSEM_GENERIC_SPINLOCK
bool
default y
config RWSEM_XCHGADD_ALGORITHM
bool
config GENERIC_CALIBRATE_DELAY
bool
default y
config X86_CMPXCHG
bool
default y
config EARLY_PRINTK
bool
default y
config GENERIC_ISA_DMA
bool
default y
config GENERIC_IOMAP
bool
default y
source "init/Kconfig"
menu "Processor type and features"
choice
prompt "Processor family"
default MK8
config MK8
bool "AMD-Opteron/Athlon64"
help
Optimize for AMD Opteron/Athlon64/Hammer/K8 CPUs.
config MPSC
bool "Intel EM64T"
help
Optimize for Intel Pentium 4 and Xeon CPUs with Intel
Extended Memory 64 Technology(EM64T). For details see
<http://www.intel.com/technology/64bitextensions/>.
config GENERIC_CPU
bool "Generic-x86-64"
help
Generic x86-64 CPU.
endchoice
#
# Define implied options from the CPU selection here
#
config X86_L1_CACHE_BYTES
int
default "128" if GENERIC_CPU || MPSC
default "64" if MK8
config X86_L1_CACHE_SHIFT
int
default "7" if GENERIC_CPU || MPSC
default "6" if MK8
config X86_TSC
bool
default y
config X86_GOOD_APIC
bool
default y
config MICROCODE
tristate "/dev/cpu/microcode - Intel CPU microcode support"
---help---
If you say Y here the 'File systems' section, you will be
able to update the microcode on Intel processors. You will
obviously need the actual microcode binary data itself which is
not shipped with the Linux kernel.
For latest news and information on obtaining all the required
ingredients for this driver, check:
<http://www.urbanmyth.org/microcode/>.
To compile this driver as a module, choose M here: the
module will be called microcode.
If you use modprobe or kmod you may also want to add the line
'alias char-major-10-184 microcode' to your /etc/modules.conf file.
config X86_MSR
tristate "/dev/cpu/*/msr - Model-specific register support"
help
This device gives privileged processes access to the x86
Model-Specific Registers (MSRs). It is a character device with
major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr.
MSR accesses are directed to a specific CPU on multi-processor
systems.
config X86_CPUID
tristate "/dev/cpu/*/cpuid - CPU information support"
help
This device gives processes access to the x86 CPUID instruction to
be executed on a specific processor. It is a character device
with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to
/dev/cpu/31/cpuid.
# disable it for opteron optimized builds because it pulls in ACPI_BOOT
config X86_HT
bool
depends on SMP && !MK8
default y
config MATH_EMULATION
bool
config MCA
bool
config EISA
bool
config X86_IO_APIC
bool
default y
config X86_LOCAL_APIC
bool
default y
config MTRR
bool "MTRR (Memory Type Range Register) support"
---help---
On Intel P6 family processors (Pentium Pro, Pentium II and later)
the Memory Type Range Registers (MTRRs) may be used to control
processor access to memory ranges. This is most useful if you have
a video (VGA) card on a PCI or AGP bus. Enabling write-combining
allows bus write transfers to be combined into a larger transfer
before bursting over the PCI/AGP bus. This can increase performance
of image write operations 2.5 times or more. Saying Y here creates a
/proc/mtrr file which may be used to manipulate your processor's
MTRRs. Typically the X server should use this.
This code has a reasonably generic interface so that similar
control registers on other processors can be easily supported
as well.
Saying Y here also fixes a problem with buggy SMP BIOSes which only
set the MTRRs for the boot CPU and not for the secondary CPUs. This
can lead to all sorts of problems, so it's good to say Y here.
Just say Y here, all x86-64 machines support MTRRs.
See <file:Documentation/mtrr.txt> for more information.
config SMP
bool "Symmetric multi-processing support"
---help---
This enables support for systems with more than one CPU. If you have
a system with only one CPU, like most personal computers, say N. If
you have a system with more than one CPU, say Y.
If you say N here, the kernel will run on single and multiprocessor
machines, but will use only one CPU of a multiprocessor machine. If
you say Y here, the kernel will run on many, but not all,
singleprocessor machines. On a singleprocessor machine, the kernel
will run faster if you say N here.
If you don't know what to do here, say N.
config PREEMPT
bool "Preemptible Kernel"
---help---
This option reduces the latency of the kernel when reacting to
real-time or interactive events by allowing a low priority process to
be preempted even if it is in kernel mode executing a system call.
This allows applications to run more reliably even when the system is
under load. On contrary it may also break your drivers and add
priority inheritance problems to your system. Don't select it if
you rely on a stable system or have slightly obscure hardware.
It's also not very well tested on x86-64 currently.
You have been warned.
Say Y here if you are feeling brave and building a kernel for a
desktop, embedded or real-time system. Say N if you are unsure.
config PREEMPT_BKL
bool "Preempt The Big Kernel Lock"
depends on PREEMPT
default y
help
This option reduces the latency of the kernel by making the
big kernel lock preemptible.
Say Y here if you are building a kernel for a desktop system.
Say N if you are unsure.
config SCHED_SMT
bool "SMT (Hyperthreading) scheduler support"
depends on SMP
default n
help
SMT scheduler support improves the CPU scheduler's decision making
when dealing with Intel Pentium 4 chips with HyperThreading at a
cost of slightly increased overhead in some places. If unsure say
N here.
config K8_NUMA
bool "K8 NUMA support"
select NUMA
depends on SMP
help
Enable NUMA (Non Unified Memory Architecture) support for
AMD Opteron Multiprocessor systems. The kernel will try to allocate
memory used by a CPU on the local memory controller of the CPU
and add some more NUMA awareness to the kernel.
This code is recommended on all multiprocessor Opteron systems
and normally doesn't hurt on others.
config NUMA_EMU
bool "NUMA emulation support"
select NUMA
depends on SMP
help
Enable NUMA emulation. A flat machine will be split
into virtual nodes when booted with "numa=fake=N", where N is the
number of nodes. This is only useful for debugging.
config ARCH_DISCONTIGMEM_ENABLE
bool
depends on NUMA
default y
config NUMA
bool
default n
config ARCH_DISCONTIGMEM_ENABLE
def_bool y
depends on NUMA
config ARCH_DISCONTIGMEM_DEFAULT
def_bool y
depends on NUMA
config ARCH_SPARSEMEM_ENABLE
def_bool y
depends on NUMA
config ARCH_FLATMEM_ENABLE
def_bool y
depends on !NUMA
source "mm/Kconfig"
config HAVE_ARCH_EARLY_PFN_TO_NID
def_bool y
config HAVE_DEC_LOCK
bool
depends on SMP
default y
config NR_CPUS
int "Maximum number of CPUs (2-256)"
range 2 256
depends on SMP
default "8"
help
This allows you to specify the maximum number of CPUs which this
kernel will support. Current maximum is 256 CPUs due to
APIC addressing limits. Less depending on the hardware.
This is purely to save memory - each supported CPU requires
memory in the static kernel configuration.
config HPET_TIMER
bool
default y
help
Use the IA-PC HPET (High Precision Event Timer) to manage
time in preference to the PIT and RTC, if a HPET is
present. The HPET provides a stable time base on SMP
systems, unlike the TSC, but it is more expensive to access,
as it is off-chip. You can find the HPET spec at
<http://www.intel.com/labs/platcomp/hpet/hpetspec.htm>.
config X86_PM_TIMER
bool "PM timer"
depends on ACPI
default y
help
Support the ACPI PM timer for time keeping. This is slow,
but is useful on some chipsets without HPET on systems with more
than one CPU. On a single processor or single socket multi core
system it is normally not required.
When the PM timer is active 64bit vsyscalls are disabled
and should not be enabled (/proc/sys/kernel/vsyscall64 should
not be changed).
The kernel selects the PM timer only as a last resort, so it is
useful to enable just in case.
config HPET_EMULATE_RTC
bool "Provide RTC interrupt"
depends on HPET_TIMER && RTC=y
config GART_IOMMU
bool "IOMMU support"
depends on PCI
help
Support the K8 IOMMU. Needed to run systems with more than 4GB of memory
properly with 32-bit PCI devices that do not support DAC (Double Address
Cycle). The IOMMU can be turned off at runtime with the iommu=off parameter.
Normally the kernel will take the right choice by itself.
If unsure, say Y.
# need this always enabled with GART_IOMMU for the VIA workaround
config SWIOTLB
bool
depends on GART_IOMMU
default y
config DUMMY_IOMMU
bool
depends on !GART_IOMMU && !SWIOTLB
default y
help
Don't use IOMMU code. This will cause problems when you have more than 4GB
of memory and any 32-bit devices. Don't turn on unless you know what you
are doing.
config X86_MCE
bool "Machine check support" if EMBEDDED
default y
help
Include a machine check error handler to report hardware errors.
This version will require the mcelog utility to decode some
machine check error logs. See
ftp://ftp.x86-64.org/pub/linux/tools/mcelog
config X86_MCE_INTEL
bool "Intel MCE features"
depends on X86_MCE && X86_LOCAL_APIC
default y
help
Additional support for intel specific MCE features such as
the thermal monitor.
config SECCOMP
bool "Enable seccomp to safely compute untrusted bytecode"
depends on PROC_FS
default y
help
This kernel feature is useful for number crunching applications
that may need to compute untrusted bytecode during their
execution. By using pipes or other transports made available to
the process as file descriptors supporting the read/write
syscalls, it's possible to isolate those applications in
their own address space using seccomp. Once seccomp is
enabled via /proc/<pid>/seccomp, it cannot be disabled
and the task is only allowed to execute a few safe syscalls
defined by each seccomp mode.
If unsure, say Y. Only embedded should say N here.
source kernel/Kconfig.hz
endmenu
#
# Use the generic interrupt handling code in kernel/irq/:
#
config GENERIC_HARDIRQS
bool
default y
config GENERIC_IRQ_PROBE
bool
default y
# we have no ISA slots, but we do have ISA-style DMA.
config ISA_DMA_API
bool
default y
menu "Power management options"
source kernel/power/Kconfig
source "drivers/acpi/Kconfig"
source "arch/x86_64/kernel/cpufreq/Kconfig"
endmenu
menu "Bus options (PCI etc.)"
config PCI
bool "PCI support"
# x86-64 doesn't support PCI BIOS access from long mode so always go direct.
config PCI_DIRECT
bool
depends on PCI
default y
config PCI_MMCONFIG
bool "Support mmconfig PCI config space access"
depends on PCI && ACPI
select ACPI_BOOT
config UNORDERED_IO
bool "Unordered IO mapping access"
depends on EXPERIMENTAL
help
Use unordered stores to access IO memory mappings in device drivers.
Still very experimental. When a driver works on IA64/ppc64/pa-risc it should
work with this option, but it makes the drivers behave differently
from i386. Requires that the driver writer used memory barriers
properly.
source "drivers/pci/pcie/Kconfig"
source "drivers/pci/Kconfig"
source "drivers/pcmcia/Kconfig"
source "drivers/pci/hotplug/Kconfig"
endmenu
menu "Executable file formats / Emulations"
source "fs/Kconfig.binfmt"
config IA32_EMULATION
bool "IA32 Emulation"
help
Include code to run 32-bit programs under a 64-bit kernel. You should likely
turn this on, unless you're 100% sure that you don't have any 32-bit programs
left.
config IA32_AOUT
bool "IA32 a.out support"
depends on IA32_EMULATION
help
Support old a.out binaries in the 32bit emulation.
config COMPAT
bool
depends on IA32_EMULATION
default y
config SYSVIPC_COMPAT
bool
depends on COMPAT && SYSVIPC
default y
config UID16
bool
depends on IA32_EMULATION
default y
endmenu
source drivers/Kconfig
source "drivers/firmware/Kconfig"
source fs/Kconfig
source "arch/x86_64/oprofile/Kconfig"
source "arch/x86_64/Kconfig.debug"
source "security/Kconfig"
source "crypto/Kconfig"
source "lib/Kconfig"
