# # 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 . 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 . 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: . 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 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 DISCONTIGMEM bool depends on NUMA default y config NUMA bool default n 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 . config X86_PM_TIMER bool "PM timer" 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//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. 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"