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+menu "Generic Driver Options"
+
+config UEVENT_HELPER
+ bool "Support for uevent helper"
+ default y
+ help
+ The uevent helper program is forked by the kernel for
+ every uevent.
+ Before the switch to the netlink-based uevent source, this was
+ used to hook hotplug scripts into kernel device events. It
+ usually pointed to a shell script at /sbin/hotplug.
+ This should not be used today, because usual systems create
+ many events at bootup or device discovery in a very short time
+ frame. One forked process per event can create so many processes
+ that it creates a high system load, or on smaller systems
+ it is known to create out-of-memory situations during bootup.
+
+config UEVENT_HELPER_PATH
+ string "path to uevent helper"
+ depends on UEVENT_HELPER
+ default ""
+ help
+ To disable user space helper program execution at by default
+ specify an empty string here. This setting can still be altered
+ via /proc/sys/kernel/hotplug or via /sys/kernel/uevent_helper
+ later at runtime.
+
+config DEVTMPFS
+ bool "Maintain a devtmpfs filesystem to mount at /dev"
+ help
+ This creates a tmpfs/ramfs filesystem instance early at bootup.
+ In this filesystem, the kernel driver core maintains device
+ nodes with their default names and permissions for all
+ registered devices with an assigned major/minor number.
+ Userspace can modify the filesystem content as needed, add
+ symlinks, and apply needed permissions.
+ It provides a fully functional /dev directory, where usually
+ udev runs on top, managing permissions and adding meaningful
+ symlinks.
+ In very limited environments, it may provide a sufficient
+ functional /dev without any further help. It also allows simple
+ rescue systems, and reliably handles dynamic major/minor numbers.
+
+ Notice: if CONFIG_TMPFS isn't enabled, the simpler ramfs
+ file system will be used instead.
+
+config DEVTMPFS_MOUNT
+ bool "Automount devtmpfs at /dev, after the kernel mounted the rootfs"
+ depends on DEVTMPFS
+ help
+ This will instruct the kernel to automatically mount the
+ devtmpfs filesystem at /dev, directly after the kernel has
+ mounted the root filesystem. The behavior can be overridden
+ with the commandline parameter: devtmpfs.mount=0|1.
+ This option does not affect initramfs based booting, here
+ the devtmpfs filesystem always needs to be mounted manually
+ after the rootfs is mounted.
+ With this option enabled, it allows to bring up a system in
+ rescue mode with init=/bin/sh, even when the /dev directory
+ on the rootfs is completely empty.
+
+config STANDALONE
+ bool "Select only drivers that don't need compile-time external firmware"
+ default y
+ help
+ Select this option if you don't have magic firmware for drivers that
+ need it.
+
+ If unsure, say Y.
+
+config PREVENT_FIRMWARE_BUILD
+ bool "Prevent firmware from being built"
+ default y
+ help
+ Say yes to avoid building firmware. Firmware is usually shipped
+ with the driver and only when updating the firmware should a
+ rebuild be made.
+ If unsure, say Y here.
+
+config FW_LOADER
+ tristate "Userspace firmware loading support" if EXPERT
+ default y
+ ---help---
+ This option is provided for the case where none of the in-tree modules
+ require userspace firmware loading support, but a module built
+ out-of-tree does.
+
+config FIRMWARE_IN_KERNEL
+ bool "Include in-kernel firmware blobs in kernel binary"
+ depends on FW_LOADER
+ default y
+ help
+ The kernel source tree includes a number of firmware 'blobs'
+ that are used by various drivers. The recommended way to
+ use these is to run "make firmware_install", which, after
+ converting ihex files to binary, copies all of the needed
+ binary files in firmware/ to /lib/firmware/ on your system so
+ that they can be loaded by userspace helpers on request.
+
+ Enabling this option will build each required firmware blob
+ into the kernel directly, where request_firmware() will find
+ them without having to call out to userspace. This may be
+ useful if your root file system requires a device that uses
+ such firmware and do not wish to use an initrd.
+
+ This single option controls the inclusion of firmware for
+ every driver that uses request_firmware() and ships its
+ firmware in the kernel source tree, which avoids a
+ proliferation of 'Include firmware for xxx device' options.
+
+ Say 'N' and let firmware be loaded from userspace.
+
+config EXTRA_FIRMWARE
+ string "External firmware blobs to build into the kernel binary"
+ depends on FW_LOADER
+ help
+ This option allows firmware to be built into the kernel for the case
+ where the user either cannot or doesn't want to provide it from
+ userspace at runtime (for example, when the firmware in question is
+ required for accessing the boot device, and the user doesn't want to
+ use an initrd).
+
+ This option is a string and takes the (space-separated) names of the
+ firmware files -- the same names that appear in MODULE_FIRMWARE()
+ and request_firmware() in the source. These files should exist under
+ the directory specified by the EXTRA_FIRMWARE_DIR option, which is
+ by default the firmware subdirectory of the kernel source tree.
+
+ For example, you might set CONFIG_EXTRA_FIRMWARE="whatever.bin", copy
+ the whatever.bin file into the firmware directory, and build the kernel.
+ Then any request_firmware("whatever.bin") will be satisfied internally
+ without needing to call out to userspace.
+
+ WARNING: If you include additional firmware files into your binary
+ kernel image that are not available under the terms of the GPL,
+ then it may be a violation of the GPL to distribute the resulting
+ image since it combines both GPL and non-GPL work. You should
+ consult a lawyer of your own before distributing such an image.
+
+config EXTRA_FIRMWARE_DIR
+ string "Firmware blobs root directory"
+ depends on EXTRA_FIRMWARE != ""
+ default "firmware"
+ help
+ This option controls the directory in which the kernel build system
+ looks for the firmware files listed in the EXTRA_FIRMWARE option.
+ The default is firmware/ in the kernel source tree, but by changing
+ this option you can point it elsewhere, such as /lib/firmware/ or
+ some other directory containing the firmware files.
+
+config FW_LOADER_USER_HELPER
+ bool
+
+config FW_LOADER_USER_HELPER_FALLBACK
+ bool "Fallback user-helper invocation for firmware loading"
+ depends on FW_LOADER
+ select FW_LOADER_USER_HELPER
+ help
+ This option enables / disables the invocation of user-helper
+ (e.g. udev) for loading firmware files as a fallback after the
+ direct file loading in kernel fails. The user-mode helper is
+ no longer required unless you have a special firmware file that
+ resides in a non-standard path. Moreover, the udev support has
+ been deprecated upstream.
+
+ If you are unsure about this, say N here.
+
+config WANT_DEV_COREDUMP
+ bool
+ help
+ Drivers should "select" this option if they desire to use the
+ device coredump mechanism.
+
+config ALLOW_DEV_COREDUMP
+ bool "Allow device coredump" if EXPERT
+ default y
+ help
+ This option controls if the device coredump mechanism is available or
+ not; if disabled, the mechanism will be omitted even if drivers that
+ can use it are enabled.
+ Say 'N' for more sensitive systems or systems that don't want
+ to ever access the information to not have the code, nor keep any
+ data.
+
+ If unsure, say Y.
+
+config DEV_COREDUMP
+ bool
+ default y if WANT_DEV_COREDUMP
+ depends on ALLOW_DEV_COREDUMP
+
+config DEBUG_DRIVER
+ bool "Driver Core verbose debug messages"
+ depends on DEBUG_KERNEL
+ help
+ Say Y here if you want the Driver core to produce a bunch of
+ debug messages to the system log. Select this if you are having a
+ problem with the driver core and want to see more of what is
+ going on.
+
+ If you are unsure about this, say N here.
+
+config DEBUG_DEVRES
+ bool "Managed device resources verbose debug messages"
+ depends on DEBUG_KERNEL
+ help
+ This option enables kernel parameter devres.log. If set to
+ non-zero, devres debug messages are printed. Select this if
+ you are having a problem with devres or want to debug
+ resource management for a managed device. devres.log can be
+ switched on and off from sysfs node.
+
+ If you are unsure about this, Say N here.
+
+config SYS_HYPERVISOR
+ bool
+ default n
+
+config GENERIC_CPU_DEVICES
+ bool
+ default n
+
+config GENERIC_CPU_AUTOPROBE
+ bool
+
+config SOC_BUS
+ bool
+
+source "drivers/base/regmap/Kconfig"
+
+config DMA_SHARED_BUFFER
+ bool
+ default n
+ select ANON_INODES
+ help
+ This option enables the framework for buffer-sharing between
+ multiple drivers. A buffer is associated with a file using driver
+ APIs extension; the file's descriptor can then be passed on to other
+ driver.
+
+config FENCE_TRACE
+ bool "Enable verbose FENCE_TRACE messages"
+ depends on DMA_SHARED_BUFFER
+ help
+ Enable the FENCE_TRACE printks. This will add extra
+ spam to the console log, but will make it easier to diagnose
+ lockup related problems for dma-buffers shared across multiple
+ devices.
+
+config DMA_CMA
+ bool "DMA Contiguous Memory Allocator"
+ depends on HAVE_DMA_CONTIGUOUS && CMA
+ help
+ This enables the Contiguous Memory Allocator which allows drivers
+ to allocate big physically-contiguous blocks of memory for use with
+ hardware components that do not support I/O map nor scatter-gather.
+
+ You can disable CMA by specifying "cma=0" on the kernel's command
+ line.
+
+ For more information see <include/linux/dma-contiguous.h>.
+ If unsure, say "n".
+
+if DMA_CMA
+comment "Default contiguous memory area size:"
+
+config CMA_SIZE_MBYTES
+ int "Size in Mega Bytes"
+ depends on !CMA_SIZE_SEL_PERCENTAGE
+ default 0 if X86
+ default 16
+ help
+ Defines the size (in MiB) of the default memory area for Contiguous
+ Memory Allocator. If the size of 0 is selected, CMA is disabled by
+ default, but it can be enabled by passing cma=size[MG] to the kernel.
+
+
+config CMA_SIZE_PERCENTAGE
+ int "Percentage of total memory"
+ depends on !CMA_SIZE_SEL_MBYTES
+ default 0 if X86
+ default 10
+ help
+ Defines the size of the default memory area for Contiguous Memory
+ Allocator as a percentage of the total memory in the system.
+ If 0 percent is selected, CMA is disabled by default, but it can be
+ enabled by passing cma=size[MG] to the kernel.
+
+choice
+ prompt "Selected region size"
+ default CMA_SIZE_SEL_MBYTES
+
+config CMA_SIZE_SEL_MBYTES
+ bool "Use mega bytes value only"
+
+config CMA_SIZE_SEL_PERCENTAGE
+ bool "Use percentage value only"
+
+config CMA_SIZE_SEL_MIN
+ bool "Use lower value (minimum)"
+
+config CMA_SIZE_SEL_MAX
+ bool "Use higher value (maximum)"
+
+endchoice
+
+config CMA_ALIGNMENT
+ int "Maximum PAGE_SIZE order of alignment for contiguous buffers"
+ range 4 12
+ default 8
+ help
+ DMA mapping framework by default aligns all buffers to the smallest
+ PAGE_SIZE order which is greater than or equal to the requested buffer
+ size. This works well for buffers up to a few hundreds kilobytes, but
+ for larger buffers it just a memory waste. With this parameter you can
+ specify the maximum PAGE_SIZE order for contiguous buffers. Larger
+ buffers will be aligned only to this specified order. The order is
+ expressed as a power of two multiplied by the PAGE_SIZE.
+
+ For example, if your system defaults to 4KiB pages, the order value
+ of 8 means that the buffers will be aligned up to 1MiB only.
+
+ If unsure, leave the default value "8".
+
+endif
+
+endmenu