Kconfig 10.3 KB
Newer Older
L
Linus Torvalds 已提交
1 2
menu "Generic Driver Options"

3 4 5
config UEVENT_HELPER
	bool "Support for uevent helper"
	default y
6
	help
7
	  The uevent helper program is forked by the kernel for
8
	  every uevent.
9 10 11 12 13 14 15 16
	  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.
17

18 19 20 21 22 23 24
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
25 26 27
	  via /proc/sys/kernel/hotplug or via /sys/kernel/uevent_helper
	  later at runtime.

28
config DEVTMPFS
29
	bool "Maintain a devtmpfs filesystem to mount at /dev"
30
	help
31
	  This creates a tmpfs/ramfs filesystem instance early at bootup.
32 33 34 35 36 37 38 39 40 41 42
	  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.
43

44 45 46
	  Notice: if CONFIG_TMPFS isn't enabled, the simpler ramfs
	  file system will be used instead.

47
config DEVTMPFS_MOUNT
48
	bool "Automount devtmpfs at /dev, after the kernel mounted the rootfs"
49 50
	depends on DEVTMPFS
	help
51 52 53 54 55 56
	  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
57
	  after the rootfs is mounted.
58 59 60
	  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.
61

L
Linus Torvalds 已提交
62
config STANDALONE
63
	bool "Select only drivers that don't need compile-time external firmware"
L
Linus Torvalds 已提交
64 65 66 67 68 69 70 71 72 73 74 75
	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
76 77 78
	  with the driver and only when updating the firmware should a
	  rebuild be made.
	  If unsure, say Y here.
L
Linus Torvalds 已提交
79 80

config FW_LOADER
81
	tristate "Userspace firmware loading support" if EXPERT
82
	default y
L
Linus Torvalds 已提交
83
	---help---
84 85 86
	  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.
L
Linus Torvalds 已提交
87

88 89 90 91 92 93
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'
94
	  that are used by various drivers. The recommended way to
95 96 97
	  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
98 99 100 101 102
	  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
103 104
	  useful if your root file system requires a device that uses
	  such firmware and do not wish to use an initrd.
105 106

	  This single option controls the inclusion of firmware for
107 108 109
	  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.
110 111 112

	  Say 'N' and let firmware be loaded from userspace.

113 114 115 116
config EXTRA_FIRMWARE
	string "External firmware blobs to build into the kernel binary"
	depends on FW_LOADER
	help
117 118
	  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
119 120 121 122
	  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).

123 124
	  This option is a string and takes the (space-separated) names of the
	  firmware files -- the same names that appear in MODULE_FIRMWARE()
125 126
	  and request_firmware() in the source. These files should exist under
	  the directory specified by the EXTRA_FIRMWARE_DIR option, which is
127
	  by default the firmware subdirectory of the kernel source tree.
128

129 130 131 132
	  For example, you might set CONFIG_EXTRA_FIRMWARE="usb8388.bin", copy
	  the usb8388.bin file into the firmware directory, and build the kernel.
	  Then any request_firmware("usb8388.bin") will be satisfied internally
	  without needing to call out to userspace.
133 134

	  WARNING: If you include additional firmware files into your binary
135
	  kernel image that are not available under the terms of the GPL,
136
	  then it may be a violation of the GPL to distribute the resulting
137
	  image since it combines both GPL and non-GPL work. You should
138 139 140 141 142 143 144 145 146
	  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.
147 148 149
	  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.
150

151 152 153 154 155 156 157 158 159 160 161
config FW_LOADER_USER_HELPER
	bool "Fallback user-helper invocation for firmware loading"
	depends on FW_LOADER
	default y
	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.

L
Linus Torvalds 已提交
162 163 164 165 166 167 168 169 170 171 172
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.

T
Tejun Heo 已提交
173 174 175 176 177 178 179 180 181 182 183 184
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.

185 186 187
config SYS_HYPERVISOR
	bool
	default n
188

189 190 191 192
config GENERIC_CPU_DEVICES
	bool
	default n

193 194 195
config GENERIC_CPU_AUTOPROBE
	bool

196 197 198
config SOC_BUS
	bool

199 200
source "drivers/base/regmap/Kconfig"

201
config DMA_SHARED_BUFFER
202
	bool
203 204 205 206 207 208 209 210
	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.

211 212 213 214 215 216 217 218 219
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.

220 221 222
config DMA_CMA
	bool "DMA Contiguous Memory Allocator"
	depends on HAVE_DMA_CONTIGUOUS && CMA
223 224 225 226 227 228 229 230
	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.

	  For more information see <include/linux/dma-contiguous.h>.
	  If unsure, say "n".

231
if  DMA_CMA
232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251
comment "Default contiguous memory area size:"

config CMA_SIZE_MBYTES
	int "Size in Mega Bytes"
	depends on !CMA_SIZE_SEL_PERCENTAGE
	default 16
	help
	  Defines the size (in MiB) of the default memory area for Contiguous
	  Memory Allocator.

config CMA_SIZE_PERCENTAGE
	int "Percentage of total memory"
	depends on !CMA_SIZE_SEL_MBYTES
	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.

choice
	prompt "Selected region size"
252
	default CMA_SIZE_SEL_MBYTES
253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269

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"
270
	range 4 12
271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297
	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".

config CMA_AREAS
	int "Maximum count of the CMA device-private areas"
	default 7
	help
	  CMA allows to create CMA areas for particular devices. This parameter
	  sets the maximum number of such device private CMA areas in the
	  system.

	  If unsure, leave the default value "7".

endif

298
endmenu