arch/ia64/Kconfig v5.13-rc1


Menu: Processor type and features

IA64

The Itanium Processor Family is Intel's 64-bit successor to
the 32-bit X86 line.  The IA-64 Linux project has a home
page at <http://www.linuxia64.org/> and a mailing list at
<linux-ia64@vger.kernel.org>.

ITANIUM

Itanium

Select your IA-64 processor type.  The default is Itanium.
This choice is safe for all IA-64 systems, but may not perform
optimally on systems with, say, Itanium 2 or newer processors.

MCKINLEY

Itanium 2

Select this to configure for an Itanium 2 (McKinley) processor.

IA64_PAGE_SIZE_4KB

4KB

This lets you select the page size of the kernel.  For best IA-64
performance, a page size of 8KB or 16KB is recommended.  For best
IA-32 compatibility, a page size of 4KB should be selected (the vast
majority of IA-32 binaries work perfectly fine with a larger page
size).  For Itanium 2 or newer systems, a page size of 64KB can also
be selected.

4KB                For best IA-32 compatibility
8KB                For best IA-64 performance
16KB               For best IA-64 performance
64KB               Requires Itanium 2 or newer processor.

If you don't know what to do, choose 16KB.

kernel/Kconfig.hz

IA64_SGI_UV

SGI-UV support

Selecting this option will add specific support for running on SGI
UV based systems.  If you have an SGI UV system or are building a
distro kernel, select this option.

IA64_HP_SBA_IOMMU

HP SBA IOMMU support

Say Y here to add support for the SBA IOMMU found on HP zx1 and
sx1000 systems.  If you're unsure, answer Y.

IA64_CYCLONE

Cyclone (EXA) Time Source support

Say Y here to enable support for IBM EXA Cyclone time source.
If you're unsure, answer N.

SMP

Symmetric multi-processing support

This enables support for systems with more than one CPU. If you have
a system with only one CPU, 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
systems, but will use only one CPU of a multiprocessor system.  If
you say Y here, the kernel will run on many, but not all,
single processor systems.  On a single processor system, the kernel
will run faster if you say N here.

See also the SMP-HOWTO available at
<http://www.tldp.org/docs.html#howto>.

If you don't know what to do here, say N.

NR_CPUS

Maximum number of CPUs (2-4096)

You should set this to the number of CPUs in your system, but
keep in mind that a kernel compiled for, e.g., 2 CPUs will boot but
only use 2 CPUs on a >2 CPU system.  Setting this to a value larger
than 64 will cause the use of a CPU mask array, causing a small
performance hit.

HOTPLUG_CPU

Support for hot-pluggable CPUs

Say Y here to experiment with turning CPUs off and on.  CPUs
can be controlled through /sys/devices/system/cpu/cpu#.
Say N if you want to disable CPU hotplug.

SCHED_SMT

SMT scheduler support

Improves the CPU scheduler's decision making when dealing with
Intel IA64 chips with MultiThreading at a cost of slightly increased
overhead in some places. If unsure say N here.

PERMIT_BSP_REMOVE

Support removal of Bootstrap Processor

Say Y here if your platform SAL will support removal of BSP with HOTPLUG_CPU
support.

FORCE_CPEI_RETARGET

Force assumption that CPEI can be re-targeted

Say Y if you need to force the assumption that CPEI can be re-targeted to
any cpu in the system. This hint is available via ACPI 3.0 specifications.
Tiger4 systems are capable of re-directing CPEI to any CPU other than BSP.
This option it useful to enable this feature on older BIOS's as well.
You can also enable this by using boot command line option force_cpei=1.

NUMA

NUMA support

Say Y to compile the kernel to support NUMA (Non-Uniform Memory
Access).  This option is for configuring high-end multiprocessor
server systems.  If in doubt, say N.

NODES_SHIFT

Max num nodes shift(3-10)

This option specifies the maximum number of nodes in your SSI system.
MAX_NUMNODES will be 2^(This value).
If in doubt, use the default.

IA64_PALINFO

/proc/pal support

If you say Y here, you are able to get PAL (Processor Abstraction
Layer) information in /proc/pal.  This contains useful information
about the processors in your systems, such as cache and TLB sizes
and the PAL firmware version in use.

To use this option, you have to ensure that the "/proc file system
support" (CONFIG_PROC_FS) is enabled, too.

IA64_MC_ERR_INJECT

MC error injection support

Adds support for MC error injection. If enabled, the kernel
will provide a sysfs interface for user applications to
call MC error injection PAL procedures to inject various errors.
This is a useful tool for MCA testing.

If you're unsure, do not select this option.

IA64_ESI

ESI (Extensible SAL Interface) support

If you say Y here, support is built into the kernel to
make ESI calls.  ESI calls are used to support vendor-specific
firmware extensions, such as the ability to inject memory-errors
for test-purposes.  If you're unsure, say N.

IA64_HP_AML_NFW

Support ACPI AML calls to native firmware

This driver installs a global ACPI Operation Region handler for
region 0xA1.  AML methods can use this OpRegion to call arbitrary
native firmware functions.  The driver installs the OpRegion
handler if there is an HPQ5001 device or if the user supplies
the "force" module parameter, e.g., with the "aml_nfw.force"
kernel command line option.

KEXEC

kexec system call

kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel.  It is like a reboot
but it is independent of the system firmware.   And like a reboot
you can start any kernel with it, not just Linux.

The name comes from the similarity to the exec system call.

It is an ongoing process to be certain the hardware in a machine
is properly shutdown, so do not be surprised if this code does not
initially work for you.  As of this writing the exact hardware
interface is strongly in flux, so no good recommendation can be
made.

CRASH_DUMP

kernel crash dumps

Generate crash dump after being started by kexec.

drivers/firmware/Kconfig



Menu: Power management and ACPI options

kernel/power/Kconfig

drivers/acpi/Kconfig


Menu: CPU Frequency scaling

drivers/cpufreq/Kconfig



MSPEC

Memory special operations driver

If you have an ia64 and you want to enable memory special
operations support (formerly known as fetchop), say Y here,
otherwise say N.