linux_dsm_epyc7002/arch/sh/Kconfig
Paul Mundt 742759eae6 sh: Handle pinmux for SH-X3 proto IRQ/IRL modes.
The SH-X3 proto CPU has all of the external IRQ and IRL pins muxed, make
sure that we're able to grab them before attempting to register their
respective IRQ controllers.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
2010-10-02 19:43:40 +09:00

904 lines
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#
# For a description of the syntax of this configuration file,
# see Documentation/kbuild/kconfig-language.txt.
#
mainmenu "Linux/SuperH Kernel Configuration"
config SUPERH
def_bool y
select EMBEDDED
select HAVE_CLK
select HAVE_IDE if HAS_IOPORT
select HAVE_MEMBLOCK
select HAVE_OPROFILE
select HAVE_GENERIC_DMA_COHERENT
select HAVE_ARCH_TRACEHOOK
select HAVE_DMA_API_DEBUG
select HAVE_DMA_ATTRS
select HAVE_PERF_EVENTS
select PERF_USE_VMALLOC
select HAVE_KERNEL_GZIP
select HAVE_KERNEL_BZIP2
select HAVE_KERNEL_LZMA
select HAVE_KERNEL_LZO
select HAVE_SYSCALL_TRACEPOINTS
select HAVE_REGS_AND_STACK_ACCESS_API
select RTC_LIB
select GENERIC_ATOMIC64
help
The SuperH is a RISC processor targeted for use in embedded systems
and consumer electronics; it was also used in the Sega Dreamcast
gaming console. The SuperH port has a home page at
<http://www.linux-sh.org/>.
config SUPERH32
def_bool ARCH = "sh"
select HAVE_KPROBES
select HAVE_KRETPROBES
select HAVE_IOREMAP_PROT if MMU && !X2TLB
select HAVE_FUNCTION_TRACER
select HAVE_FTRACE_MCOUNT_RECORD
select HAVE_DYNAMIC_FTRACE
select HAVE_FUNCTION_TRACE_MCOUNT_TEST
select HAVE_FTRACE_NMI_ENTER if DYNAMIC_FTRACE
select HAVE_FUNCTION_GRAPH_TRACER
select HAVE_ARCH_KGDB
select HAVE_HW_BREAKPOINT
select HAVE_MIXED_BREAKPOINTS_REGS
select PERF_EVENTS
select ARCH_HIBERNATION_POSSIBLE if MMU
config SUPERH64
def_bool ARCH = "sh64"
config ARCH_DEFCONFIG
string
default "arch/sh/configs/shx3_defconfig" if SUPERH32
default "arch/sh/configs/cayman_defconfig" if SUPERH64
config RWSEM_GENERIC_SPINLOCK
def_bool y
config RWSEM_XCHGADD_ALGORITHM
bool
config GENERIC_BUG
def_bool y
depends on BUG && SUPERH32
config GENERIC_CSUM
def_bool y
depends on SUPERH64
config GENERIC_FIND_NEXT_BIT
def_bool y
config GENERIC_HWEIGHT
def_bool y
config GENERIC_HARDIRQS
def_bool y
config GENERIC_HARDIRQS_NO__DO_IRQ
def_bool y
config IRQ_PER_CPU
def_bool y
config SPARSE_IRQ
def_bool y
depends on SUPERH32
config GENERIC_GPIO
def_bool n
config GENERIC_CALIBRATE_DELAY
bool
config GENERIC_IOMAP
bool
config GENERIC_CLOCKEVENTS
def_bool y
config GENERIC_CLOCKEVENTS_BROADCAST
bool
config GENERIC_CMOS_UPDATE
def_bool y
depends on SH_SH03 || SH_DREAMCAST
config GENERIC_LOCKBREAK
def_bool y
depends on SMP && PREEMPT
config SYS_SUPPORTS_PM
bool
depends on !SMP
config ARCH_SUSPEND_POSSIBLE
def_bool n
config ARCH_HIBERNATION_POSSIBLE
def_bool n
config SYS_SUPPORTS_APM_EMULATION
bool
select ARCH_SUSPEND_POSSIBLE
config SYS_SUPPORTS_HUGETLBFS
bool
config SYS_SUPPORTS_SMP
bool
config SYS_SUPPORTS_NUMA
bool
config SYS_SUPPORTS_PCI
bool
config SYS_SUPPORTS_CMT
bool
config SYS_SUPPORTS_MTU2
bool
config SYS_SUPPORTS_TMU
bool
config STACKTRACE_SUPPORT
def_bool y
config LOCKDEP_SUPPORT
def_bool y
config HAVE_LATENCYTOP_SUPPORT
def_bool y
config ARCH_HAS_ILOG2_U32
def_bool n
config ARCH_HAS_ILOG2_U64
def_bool n
config ARCH_NO_VIRT_TO_BUS
def_bool y
config ARCH_HAS_DEFAULT_IDLE
def_bool y
config ARCH_HAS_CPU_IDLE_WAIT
def_bool y
config NO_IOPORT
bool
config IO_TRAPPED
bool
config DMA_COHERENT
bool
config DMA_NONCOHERENT
def_bool !DMA_COHERENT
config NEED_DMA_MAP_STATE
def_bool DMA_NONCOHERENT
config NEED_SG_DMA_LENGTH
def_bool y
source "init/Kconfig"
source "kernel/Kconfig.freezer"
menu "System type"
#
# Processor families
#
config CPU_SH2
bool
config CPU_SH2A
bool
select CPU_SH2
config CPU_SH3
bool
select CPU_HAS_INTEVT
select CPU_HAS_SR_RB
select SYS_SUPPORTS_TMU
config CPU_SH4
bool
select CPU_HAS_INTEVT
select CPU_HAS_SR_RB
select CPU_HAS_FPU if !CPU_SH4AL_DSP
select SYS_SUPPORTS_TMU
select SYS_SUPPORTS_HUGETLBFS if MMU
config CPU_SH4A
bool
select CPU_SH4
config CPU_SH4AL_DSP
bool
select CPU_SH4A
select CPU_HAS_DSP
config CPU_SH5
bool
select CPU_HAS_FPU
select SYS_SUPPORTS_TMU
select SYS_SUPPORTS_HUGETLBFS if MMU
config CPU_SHX2
bool
config CPU_SHX3
bool
select DMA_COHERENT
select SYS_SUPPORTS_SMP
select SYS_SUPPORTS_NUMA
config ARCH_SHMOBILE
bool
select ARCH_SUSPEND_POSSIBLE
select PM
select PM_RUNTIME
if SUPERH32
choice
prompt "Processor sub-type selection"
#
# Processor subtypes
#
# SH-2 Processor Support
config CPU_SUBTYPE_SH7619
bool "Support SH7619 processor"
select CPU_SH2
select SYS_SUPPORTS_CMT
# SH-2A Processor Support
config CPU_SUBTYPE_SH7201
bool "Support SH7201 processor"
select CPU_SH2A
select CPU_HAS_FPU
select SYS_SUPPORTS_MTU2
config CPU_SUBTYPE_SH7203
bool "Support SH7203 processor"
select CPU_SH2A
select CPU_HAS_FPU
select SYS_SUPPORTS_CMT
select SYS_SUPPORTS_MTU2
config CPU_SUBTYPE_SH7206
bool "Support SH7206 processor"
select CPU_SH2A
select SYS_SUPPORTS_CMT
select SYS_SUPPORTS_MTU2
config CPU_SUBTYPE_SH7263
bool "Support SH7263 processor"
select CPU_SH2A
select CPU_HAS_FPU
select SYS_SUPPORTS_CMT
select SYS_SUPPORTS_MTU2
config CPU_SUBTYPE_MXG
bool "Support MX-G processor"
select CPU_SH2A
select SYS_SUPPORTS_MTU2
help
Select MX-G if running on an R8A03022BG part.
# SH-3 Processor Support
config CPU_SUBTYPE_SH7705
bool "Support SH7705 processor"
select CPU_SH3
config CPU_SUBTYPE_SH7706
bool "Support SH7706 processor"
select CPU_SH3
help
Select SH7706 if you have a 133 Mhz SH-3 HD6417706 CPU.
config CPU_SUBTYPE_SH7707
bool "Support SH7707 processor"
select CPU_SH3
help
Select SH7707 if you have a 60 Mhz SH-3 HD6417707 CPU.
config CPU_SUBTYPE_SH7708
bool "Support SH7708 processor"
select CPU_SH3
help
Select SH7708 if you have a 60 Mhz SH-3 HD6417708S or
if you have a 100 Mhz SH-3 HD6417708R CPU.
config CPU_SUBTYPE_SH7709
bool "Support SH7709 processor"
select CPU_SH3
help
Select SH7709 if you have a 80 Mhz SH-3 HD6417709 CPU.
config CPU_SUBTYPE_SH7710
bool "Support SH7710 processor"
select CPU_SH3
select CPU_HAS_DSP
help
Select SH7710 if you have a SH3-DSP SH7710 CPU.
config CPU_SUBTYPE_SH7712
bool "Support SH7712 processor"
select CPU_SH3
select CPU_HAS_DSP
help
Select SH7712 if you have a SH3-DSP SH7712 CPU.
config CPU_SUBTYPE_SH7720
bool "Support SH7720 processor"
select CPU_SH3
select CPU_HAS_DSP
select SYS_SUPPORTS_CMT
help
Select SH7720 if you have a SH3-DSP SH7720 CPU.
config CPU_SUBTYPE_SH7721
bool "Support SH7721 processor"
select CPU_SH3
select CPU_HAS_DSP
select SYS_SUPPORTS_CMT
help
Select SH7721 if you have a SH3-DSP SH7721 CPU.
# SH-4 Processor Support
config CPU_SUBTYPE_SH7750
bool "Support SH7750 processor"
select CPU_SH4
help
Select SH7750 if you have a 200 Mhz SH-4 HD6417750 CPU.
config CPU_SUBTYPE_SH7091
bool "Support SH7091 processor"
select CPU_SH4
help
Select SH7091 if you have an SH-4 based Sega device (such as
the Dreamcast, Naomi, and Naomi 2).
config CPU_SUBTYPE_SH7750R
bool "Support SH7750R processor"
select CPU_SH4
config CPU_SUBTYPE_SH7750S
bool "Support SH7750S processor"
select CPU_SH4
config CPU_SUBTYPE_SH7751
bool "Support SH7751 processor"
select CPU_SH4
help
Select SH7751 if you have a 166 Mhz SH-4 HD6417751 CPU,
or if you have a HD6417751R CPU.
config CPU_SUBTYPE_SH7751R
bool "Support SH7751R processor"
select CPU_SH4
config CPU_SUBTYPE_SH7760
bool "Support SH7760 processor"
select CPU_SH4
config CPU_SUBTYPE_SH4_202
bool "Support SH4-202 processor"
select CPU_SH4
# SH-4A Processor Support
config CPU_SUBTYPE_SH7723
bool "Support SH7723 processor"
select CPU_SH4A
select CPU_SHX2
select ARCH_SHMOBILE
select ARCH_SPARSEMEM_ENABLE
select SYS_SUPPORTS_CMT
help
Select SH7723 if you have an SH-MobileR2 CPU.
config CPU_SUBTYPE_SH7724
bool "Support SH7724 processor"
select CPU_SH4A
select CPU_SHX2
select ARCH_SHMOBILE
select ARCH_SPARSEMEM_ENABLE
select SYS_SUPPORTS_CMT
help
Select SH7724 if you have an SH-MobileR2R CPU.
config CPU_SUBTYPE_SH7757
bool "Support SH7757 processor"
select CPU_SH4A
select CPU_SHX2
help
Select SH7757 if you have a SH4A SH7757 CPU.
config CPU_SUBTYPE_SH7763
bool "Support SH7763 processor"
select CPU_SH4A
help
Select SH7763 if you have a SH4A SH7763(R5S77631) CPU.
config CPU_SUBTYPE_SH7770
bool "Support SH7770 processor"
select CPU_SH4A
config CPU_SUBTYPE_SH7780
bool "Support SH7780 processor"
select CPU_SH4A
config CPU_SUBTYPE_SH7785
bool "Support SH7785 processor"
select CPU_SH4A
select CPU_SHX2
select ARCH_SPARSEMEM_ENABLE
select SYS_SUPPORTS_NUMA
config CPU_SUBTYPE_SH7786
bool "Support SH7786 processor"
select CPU_SH4A
select CPU_SHX3
select CPU_HAS_PTEAEX
select GENERIC_CLOCKEVENTS_BROADCAST if SMP
config CPU_SUBTYPE_SHX3
bool "Support SH-X3 processor"
select CPU_SH4A
select CPU_SHX3
select GENERIC_CLOCKEVENTS_BROADCAST if SMP
select ARCH_REQUIRE_GPIOLIB
# SH4AL-DSP Processor Support
config CPU_SUBTYPE_SH7343
bool "Support SH7343 processor"
select CPU_SH4AL_DSP
select ARCH_SHMOBILE
select SYS_SUPPORTS_CMT
config CPU_SUBTYPE_SH7722
bool "Support SH7722 processor"
select CPU_SH4AL_DSP
select CPU_SHX2
select ARCH_SHMOBILE
select ARCH_SPARSEMEM_ENABLE
select SYS_SUPPORTS_NUMA
select SYS_SUPPORTS_CMT
config CPU_SUBTYPE_SH7366
bool "Support SH7366 processor"
select CPU_SH4AL_DSP
select CPU_SHX2
select ARCH_SHMOBILE
select ARCH_SPARSEMEM_ENABLE
select SYS_SUPPORTS_NUMA
select SYS_SUPPORTS_CMT
endchoice
endif
if SUPERH64
choice
prompt "Processor sub-type selection"
# SH-5 Processor Support
config CPU_SUBTYPE_SH5_101
bool "Support SH5-101 processor"
select CPU_SH5
config CPU_SUBTYPE_SH5_103
bool "Support SH5-103 processor"
select CPU_SH5
endchoice
endif
source "arch/sh/mm/Kconfig"
source "arch/sh/Kconfig.cpu"
source "arch/sh/boards/Kconfig"
menu "Timer and clock configuration"
config SH_TIMER_TMU
bool "TMU timer driver"
depends on SYS_SUPPORTS_TMU
default y
help
This enables the build of the TMU timer driver.
config SH_TIMER_CMT
bool "CMT timer driver"
depends on SYS_SUPPORTS_CMT
default y
help
This enables build of the CMT timer driver.
config SH_TIMER_MTU2
bool "MTU2 timer driver"
depends on SYS_SUPPORTS_MTU2
default y
help
This enables build of the MTU2 timer driver.
config SH_PCLK_FREQ
int "Peripheral clock frequency (in Hz)"
depends on SH_CLK_CPG_LEGACY
default "31250000" if CPU_SUBTYPE_SH7619
default "33333333" if CPU_SUBTYPE_SH7770 || \
CPU_SUBTYPE_SH7760 || \
CPU_SUBTYPE_SH7705 || \
CPU_SUBTYPE_SH7203 || \
CPU_SUBTYPE_SH7206 || \
CPU_SUBTYPE_SH7263 || \
CPU_SUBTYPE_MXG
default "60000000" if CPU_SUBTYPE_SH7751 || CPU_SUBTYPE_SH7751R
default "66000000" if CPU_SUBTYPE_SH4_202
default "50000000"
help
This option is used to specify the peripheral clock frequency.
This is necessary for determining the reference clock value on
platforms lacking an RTC.
config SH_CLK_CPG
def_bool y
config SH_CLK_CPG_LEGACY
depends on SH_CLK_CPG
def_bool y if !CPU_SUBTYPE_SH7785 && !ARCH_SHMOBILE && \
!CPU_SHX3 && !CPU_SUBTYPE_SH7757
config SH_CLK_MD
int "CPU Mode Pin Setting"
depends on CPU_SH2
default 6 if CPU_SUBTYPE_SH7206
default 5 if CPU_SUBTYPE_SH7619
default 0
help
MD2 - MD0 pin setting.
source "kernel/time/Kconfig"
endmenu
menu "CPU Frequency scaling"
source "drivers/cpufreq/Kconfig"
config SH_CPU_FREQ
tristate "SuperH CPU Frequency driver"
depends on CPU_FREQ
select CPU_FREQ_TABLE
help
This adds the cpufreq driver for SuperH. Any CPU that supports
clock rate rounding through the clock framework can use this
driver. While it will make the kernel slightly larger, this is
harmless for CPUs that don't support rate rounding. The driver
will also generate a notice in the boot log before disabling
itself if the CPU in question is not capable of rate rounding.
For details, take a look at <file:Documentation/cpu-freq>.
If unsure, say N.
endmenu
source "arch/sh/drivers/Kconfig"
endmenu
menu "Kernel features"
source kernel/Kconfig.hz
config KEXEC
bool "kexec system call (EXPERIMENTAL)"
depends on SUPERH32 && EXPERIMENTAL && MMU
help
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. It may help to enable device hotplugging
support. As of this writing the exact hardware interface is
strongly in flux, so no good recommendation can be made.
config CRASH_DUMP
bool "kernel crash dumps (EXPERIMENTAL)"
depends on SUPERH32 && EXPERIMENTAL && BROKEN_ON_SMP
help
Generate crash dump after being started by kexec.
This should be normally only set in special crash dump kernels
which are loaded in the main kernel with kexec-tools into
a specially reserved region and then later executed after
a crash by kdump/kexec. The crash dump kernel must be compiled
to a memory address not used by the main kernel using
MEMORY_START.
For more details see Documentation/kdump/kdump.txt
config KEXEC_JUMP
bool "kexec jump (EXPERIMENTAL)"
depends on SUPERH32 && KEXEC && HIBERNATION && EXPERIMENTAL
help
Jump between original kernel and kexeced kernel and invoke
code via KEXEC
config SECCOMP
bool "Enable seccomp to safely compute untrusted bytecode"
depends on PROC_FS
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 prctl, it cannot be disabled and the task is only
allowed to execute a few safe syscalls defined by each seccomp
mode.
If unsure, say N.
config SMP
bool "Symmetric multi-processing support"
depends on SYS_SUPPORTS_SMP
select USE_GENERIC_SMP_HELPERS
---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.
People using multiprocessor machines who say Y here should also say
Y to "Enhanced Real Time Clock Support", below.
See also <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO
available at <http://www.tldp.org/docs.html#howto>.
If you don't know what to do here, say N.
config NR_CPUS
int "Maximum number of CPUs (2-32)"
range 2 32
depends on SMP
default "4" if CPU_SUBTYPE_SHX3
default "2"
help
This allows you to specify the maximum number of CPUs which this
kernel will support. The maximum supported value is 32 and the
minimum value which makes sense is 2.
This is purely to save memory - each supported CPU adds
approximately eight kilobytes to the kernel image.
config HOTPLUG_CPU
bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
depends on SMP && HOTPLUG && EXPERIMENTAL
help
Say Y here to experiment with turning CPUs off and on. CPUs
can be controlled through /sys/devices/system/cpu.
source "kernel/Kconfig.preempt"
config GUSA
def_bool y
depends on !SMP && SUPERH32
help
This enables support for gUSA (general UserSpace Atomicity).
This is the default implementation for both UP and non-ll/sc
CPUs, and is used by the libc, amongst others.
For additional information, design information can be found
in <http://lc.linux.or.jp/lc2002/papers/niibe0919p.pdf>.
This should only be disabled for special cases where alternate
atomicity implementations exist.
config GUSA_RB
bool "Implement atomic operations by roll-back (gRB) (EXPERIMENTAL)"
depends on GUSA && CPU_SH3 || (CPU_SH4 && !CPU_SH4A)
help
Enabling this option will allow the kernel to implement some
atomic operations using a software implementation of load-locked/
store-conditional (LLSC). On machines which do not have hardware
LLSC, this should be more efficient than the other alternative of
disabling interrupts around the atomic sequence.
source "drivers/sh/Kconfig"
endmenu
menu "Boot options"
config ZERO_PAGE_OFFSET
hex
default "0x00010000" if PAGE_SIZE_64KB || SH_RTS7751R2D || \
SH_7751_SOLUTION_ENGINE
default "0x00004000" if PAGE_SIZE_16KB || SH_SH03
default "0x00002000" if PAGE_SIZE_8KB
default "0x00001000"
help
This sets the default offset of zero page.
config BOOT_LINK_OFFSET
hex
default "0x00210000" if SH_SHMIN
default "0x00400000" if SH_CAYMAN
default "0x00810000" if SH_7780_SOLUTION_ENGINE
default "0x009e0000" if SH_TITAN
default "0x01800000" if SH_SDK7780
default "0x02000000" if SH_EDOSK7760
default "0x00800000"
help
This option allows you to set the link address offset of the zImage.
This can be useful if you are on a board which has a small amount of
memory.
config ENTRY_OFFSET
hex
default "0x00001000" if PAGE_SIZE_4KB
default "0x00002000" if PAGE_SIZE_8KB
default "0x00004000" if PAGE_SIZE_16KB
default "0x00010000" if PAGE_SIZE_64KB
default "0x00000000"
config ROMIMAGE_MMCIF
bool "Include MMCIF loader in romImage (EXPERIMENTAL)"
depends on CPU_SUBTYPE_SH7724 && EXPERIMENTAL
help
Say Y here to include experimental MMCIF loading code in
romImage. With this enabled it is possible to write the romImage
kernel image to an MMC card and boot the kernel straight from
the reset vector. At reset the processor Mask ROM will load the
first part of the romImage which in turn loads the rest the kernel
image to RAM using the MMCIF hardware block.
choice
prompt "Kernel command line"
optional
default CMDLINE_OVERWRITE
help
Setting this option allows the kernel command line arguments
to be set.
config CMDLINE_OVERWRITE
bool "Overwrite bootloader kernel arguments"
help
Given string will overwrite any arguments passed in by
a bootloader.
config CMDLINE_EXTEND
bool "Extend bootloader kernel arguments"
help
Given string will be concatenated with arguments passed in
by a bootloader.
endchoice
config CMDLINE
string "Kernel command line arguments string"
depends on CMDLINE_OVERWRITE || CMDLINE_EXTEND
default "console=ttySC1,115200"
endmenu
menu "Bus options"
config SUPERHYWAY
tristate "SuperHyway Bus support"
depends on CPU_SUBTYPE_SH4_202
config MAPLE
bool "Maple Bus support"
depends on SH_DREAMCAST
help
The Maple Bus is SEGA's serial communication bus for peripherals
on the Dreamcast. Without this bus support you won't be able to
get your Dreamcast keyboard etc to work, so most users
probably want to say 'Y' here, unless you are only using the
Dreamcast with a serial line terminal or a remote network
connection.
config PCI
bool "PCI support"
depends on SYS_SUPPORTS_PCI
select PCI_DOMAINS
help
Find out whether you have a PCI motherboard. PCI is the name of a
bus system, i.e. the way the CPU talks to the other stuff inside
your box. If you have PCI, say Y, otherwise N.
config PCI_DOMAINS
bool
source "drivers/pci/pcie/Kconfig"
source "drivers/pci/Kconfig"
source "drivers/pcmcia/Kconfig"
source "drivers/pci/hotplug/Kconfig"
endmenu
menu "Executable file formats"
source "fs/Kconfig.binfmt"
endmenu
menu "Power management options (EXPERIMENTAL)"
depends on EXPERIMENTAL
source "kernel/power/Kconfig"
source "drivers/cpuidle/Kconfig"
endmenu
source "net/Kconfig"
source "drivers/Kconfig"
source "fs/Kconfig"
source "arch/sh/Kconfig.debug"
source "security/Kconfig"
source "crypto/Kconfig"
menuconfig VIRTUALIZATION
bool "Virtualization"
default n
---help---
Say Y here to get to see options for using your Linux host to run other
operating systems inside virtual machines (guests).
This option alone does not add any kernel code.
If you say N, all options in this submenu will be skipped and disabled.
if VIRTUALIZATION
source drivers/virtio/Kconfig
endif # VIRTUALIZATION
source "lib/Kconfig"