[deliverable/linux.git] / lib / Kconfig

#
# Library configuration
#

config BINARY_PRINTF
	def_bool n

menu "Library routines"

config RAID6_PQ
	tristate

config BITREVERSE
	tristate

config RATIONAL
	boolean

config GENERIC_STRNCPY_FROM_USER
	bool

config GENERIC_STRNLEN_USER
	bool

config GENERIC_NET_UTILS
	bool

config GENERIC_FIND_FIRST_BIT
	bool

config NO_GENERIC_PCI_IOPORT_MAP
	bool

config GENERIC_PCI_IOMAP
	bool

config GENERIC_IOMAP
	bool
	select GENERIC_PCI_IOMAP

config GENERIC_IO
	boolean
	default n

config STMP_DEVICE
	bool

config PERCPU_RWSEM
	boolean

config CRC_CCITT
	tristate "CRC-CCITT functions"
	help
	  This option is provided for the case where no in-kernel-tree
	  modules require CRC-CCITT functions, but a module built outside
	  the kernel tree does. Such modules that use library CRC-CCITT
	  functions require M here.

config CRC16
	tristate "CRC16 functions"
	help
	  This option is provided for the case where no in-kernel-tree
	  modules require CRC16 functions, but a module built outside
	  the kernel tree does. Such modules that use library CRC16
	  functions require M here.

config CRC_T10DIF
	tristate "CRC calculation for the T10 Data Integrity Field"
	help
	  This option is only needed if a module that's not in the
	  kernel tree needs to calculate CRC checks for use with the
	  SCSI data integrity subsystem.

config CRC_ITU_T
	tristate "CRC ITU-T V.41 functions"
	help
	  This option is provided for the case where no in-kernel-tree
	  modules require CRC ITU-T V.41 functions, but a module built outside
	  the kernel tree does. Such modules that use library CRC ITU-T V.41
	  functions require M here.

config CRC32
	tristate "CRC32/CRC32c functions"
	default y
	select BITREVERSE
	help
	  This option is provided for the case where no in-kernel-tree
	  modules require CRC32/CRC32c functions, but a module built outside
	  the kernel tree does. Such modules that use library CRC32/CRC32c
	  functions require M here.

config CRC32_SELFTEST
	bool "CRC32 perform self test on init"
	default n
	depends on CRC32
	help
	  This option enables the CRC32 library functions to perform a
	  self test on initialization. The self test computes crc32_le
	  and crc32_be over byte strings with random alignment and length
	  and computes the total elapsed time and number of bytes processed.

choice
	prompt "CRC32 implementation"
	depends on CRC32
	default CRC32_SLICEBY8
	help
	  This option allows a kernel builder to override the default choice
	  of CRC32 algorithm.  Choose the default ("slice by 8") unless you
	  know that you need one of the others.

config CRC32_SLICEBY8
	bool "Slice by 8 bytes"
	help
	  Calculate checksum 8 bytes at a time with a clever slicing algorithm.
	  This is the fastest algorithm, but comes with a 8KiB lookup table.
	  Most modern processors have enough cache to hold this table without
	  thrashing the cache.

	  This is the default implementation choice.  Choose this one unless
	  you have a good reason not to.

config CRC32_SLICEBY4
	bool "Slice by 4 bytes"
	help
	  Calculate checksum 4 bytes at a time with a clever slicing algorithm.
	  This is a bit slower than slice by 8, but has a smaller 4KiB lookup
	  table.

	  Only choose this option if you know what you are doing.

config CRC32_SARWATE
	bool "Sarwate's Algorithm (one byte at a time)"
	help
	  Calculate checksum a byte at a time using Sarwate's algorithm.  This
	  is not particularly fast, but has a small 256 byte lookup table.

	  Only choose this option if you know what you are doing.

config CRC32_BIT
	bool "Classic Algorithm (one bit at a time)"
	help
	  Calculate checksum one bit at a time.  This is VERY slow, but has
	  no lookup table.  This is provided as a debugging option.

	  Only choose this option if you are debugging crc32.

endchoice

config CRC7
	tristate "CRC7 functions"
	help
	  This option is provided for the case where no in-kernel-tree
	  modules require CRC7 functions, but a module built outside
	  the kernel tree does. Such modules that use library CRC7
	  functions require M here.

config LIBCRC32C
	tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check"
	select CRYPTO
	select CRYPTO_CRC32C
	help
	  This option is provided for the case where no in-kernel-tree
	  modules require CRC32c functions, but a module built outside the
	  kernel tree does. Such modules that use library CRC32c functions
	  require M here.  See Castagnoli93.
	  Module will be libcrc32c.

config CRC8
	tristate "CRC8 function"
	help
	  This option provides CRC8 function. Drivers may select this
	  when they need to do cyclic redundancy check according CRC8
	  algorithm. Module will be called crc8.

config AUDIT_GENERIC
	bool
	depends on AUDIT && !AUDIT_ARCH
	default y

#
# compression support is select'ed if needed
#
config ZLIB_INFLATE
	tristate

config ZLIB_DEFLATE
	tristate

config LZO_COMPRESS
	tristate

config LZO_DECOMPRESS
	tristate

config LZ4_COMPRESS
	tristate

config LZ4HC_COMPRESS
	tristate

config LZ4_DECOMPRESS
	tristate

source "lib/xz/Kconfig"

#
# These all provide a common interface (hence the apparent duplication with
# ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.)
#
config DECOMPRESS_GZIP
	select ZLIB_INFLATE
	tristate

config DECOMPRESS_BZIP2
	tristate

config DECOMPRESS_LZMA
	tristate

config DECOMPRESS_XZ
	select XZ_DEC
	tristate

config DECOMPRESS_LZO
	select LZO_DECOMPRESS
	tristate

config DECOMPRESS_LZ4
	select LZ4_DECOMPRESS
	tristate

#
# Generic allocator support is selected if needed
#
config GENERIC_ALLOCATOR
	boolean

#
# reed solomon support is select'ed if needed
#
config REED_SOLOMON
	tristate
	
config REED_SOLOMON_ENC8
	boolean

config REED_SOLOMON_DEC8
	boolean

config REED_SOLOMON_ENC16
	boolean

config REED_SOLOMON_DEC16
	boolean

#
# BCH support is selected if needed
#
config BCH
	tristate

config BCH_CONST_PARAMS
	boolean
	help
	  Drivers may select this option to force specific constant
	  values for parameters 'm' (Galois field order) and 't'
	  (error correction capability). Those specific values must
	  be set by declaring default values for symbols BCH_CONST_M
	  and BCH_CONST_T.
	  Doing so will enable extra compiler optimizations,
	  improving encoding and decoding performance up to 2x for
	  usual (m,t) values (typically such that m*t < 200).
	  When this option is selected, the BCH library supports
	  only a single (m,t) configuration. This is mainly useful
	  for NAND flash board drivers requiring known, fixed BCH
	  parameters.

config BCH_CONST_M
	int
	range 5 15
	help
	  Constant value for Galois field order 'm'. If 'k' is the
	  number of data bits to protect, 'm' should be chosen such
	  that (k + m*t) <= 2**m - 1.
	  Drivers should declare a default value for this symbol if
	  they select option BCH_CONST_PARAMS.

config BCH_CONST_T
	int
	help
	  Constant value for error correction capability in bits 't'.
	  Drivers should declare a default value for this symbol if
	  they select option BCH_CONST_PARAMS.

#
# Textsearch support is select'ed if needed
#
config TEXTSEARCH
	boolean

config TEXTSEARCH_KMP
	tristate

config TEXTSEARCH_BM
	tristate

config TEXTSEARCH_FSM
	tristate

config BTREE
	boolean

config HAS_IOMEM
	boolean
	depends on !NO_IOMEM
	select GENERIC_IO
	default y

config HAS_IOPORT
	boolean
	depends on HAS_IOMEM && !NO_IOPORT
	default y

config HAS_DMA
	boolean
	depends on !NO_DMA
	default y

config CHECK_SIGNATURE
	bool

config CPUMASK_OFFSTACK
	bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
	help
	  Use dynamic allocation for cpumask_var_t, instead of putting
	  them on the stack.  This is a bit more expensive, but avoids
	  stack overflow.

config DISABLE_OBSOLETE_CPUMASK_FUNCTIONS
       bool "Disable obsolete cpumask functions" if DEBUG_PER_CPU_MAPS
       depends on BROKEN

config CPU_RMAP
	bool
	depends on SMP

config DQL
	bool

#
# Netlink attribute parsing support is select'ed if needed
#
config NLATTR
	bool

#
# Generic 64-bit atomic support is selected if needed
#
config GENERIC_ATOMIC64
       bool

config ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
	def_bool y if GENERIC_ATOMIC64

config LRU_CACHE
	tristate

config AVERAGE
	bool "Averaging functions"
	help
	  This option is provided for the case where no in-kernel-tree
	  modules require averaging functions, but a module built outside
	  the kernel tree does. Such modules that use library averaging
	  functions require Y here.

	  If unsure, say N.

config CLZ_TAB
	bool

config CORDIC
	tristate "CORDIC algorithm"
	help
	  This option provides an implementation of the CORDIC algorithm;
	  calculations are in fixed point. Module will be called cordic.

config DDR
	bool "JEDEC DDR data"
	help
	  Data from JEDEC specs for DDR SDRAM memories,
	  particularly the AC timing parameters and addressing
	  information. This data is useful for drivers handling
	  DDR SDRAM controllers.

config MPILIB
	tristate
	select CLZ_TAB
	help
	  Multiprecision maths library from GnuPG.
	  It is used to implement RSA digital signature verification,
	  which is used by IMA/EVM digital signature extension.

config SIGNATURE
	tristate
	depends on KEYS && CRYPTO
	select CRYPTO_SHA1
	select MPILIB
	help
	  Digital signature verification. Currently only RSA is supported.
	  Implementation is done using GnuPG MPI library

#
# libfdt files, only selected if needed.
#
config LIBFDT
	bool

config OID_REGISTRY
	tristate
	help
	  Enable fast lookup object identifier registry.

config UCS2_STRING
        tristate

source "lib/fonts/Kconfig"

endmenu
Commit	Line	Data
1da177e4 LT	1	#
	2	# Library configuration
	3	#
	4
4370aa4a LJ	5	config BINARY_PRINTF
	6	def_bool n
	7
1da177e4 LT	8	menu "Library routines"
1da177e4 LT	9
f5e70d0f DW	10	config RAID6_PQ
	11	tristate
	12
a5cfc1ec AM	13	config BITREVERSE
	14	tristate
	15
8759ef32 OS	16	config RATIONAL
	17	boolean
	18
2922585b DM	19	config GENERIC_STRNCPY_FROM_USER
	20	bool
	21
a08c5356 LT	22	config GENERIC_STRNLEN_USER
	23	bool
	24
4cd5773a AS	25	config GENERIC_NET_UTILS
	26	bool
	27
19870def	28	config GENERIC_FIND_FIRST_BIT
9ba16087	29	bool
19870def	30
b923650b MT	31	config NO_GENERIC_PCI_IOPORT_MAP
	32	bool
	33
66eab4df MT	34	config GENERIC_PCI_IOMAP
	35	bool
	36
4673ca8e MT	37	config GENERIC_IOMAP
4673ca8e MT	38	bool
66eab4df	39	select GENERIC_PCI_IOMAP
4673ca8e	40
087fafd1 RW	41	config GENERIC_IO
	42	boolean
	43	default n
	44
4ccf4bea WS	45	config STMP_DEVICE
	46	bool
	47
22b361d1 ON	48	config PERCPU_RWSEM
	49	boolean
	50
1da177e4 LT	51	config CRC_CCITT
	52	tristate "CRC-CCITT functions"
	53	help
	54	This option is provided for the case where no in-kernel-tree
	55	modules require CRC-CCITT functions, but a module built outside
	56	the kernel tree does. Such modules that use library CRC-CCITT
	57	functions require M here.
	58
7657ec1f EP	59	config CRC16
	60	tristate "CRC16 functions"
	61	help
	62	This option is provided for the case where no in-kernel-tree
	63	modules require CRC16 functions, but a module built outside
	64	the kernel tree does. Such modules that use library CRC16
	65	functions require M here.
	66
f11f594e MP	67	config CRC_T10DIF
	68	tristate "CRC calculation for the T10 Data Integrity Field"
	69	help
	70	This option is only needed if a module that's not in the
	71	kernel tree needs to calculate CRC checks for use with the
	72	SCSI data integrity subsystem.
	73
3e7cbae7 ID	74	config CRC_ITU_T
	75	tristate "CRC ITU-T V.41 functions"
	76	help
	77	This option is provided for the case where no in-kernel-tree
	78	modules require CRC ITU-T V.41 functions, but a module built outside
	79	the kernel tree does. Such modules that use library CRC ITU-T V.41
	80	functions require M here.
	81
1da177e4	82	config CRC32
46c5801e	83	tristate "CRC32/CRC32c functions"
1da177e4	84	default y
906d66df	85	select BITREVERSE
1da177e4 LT	86	help
1da177e4 LT	87	This option is provided for the case where no in-kernel-tree
46c5801e DW	88	modules require CRC32/CRC32c functions, but a module built outside
	89	the kernel tree does. Such modules that use library CRC32/CRC32c
	90	functions require M here.
1da177e4	91
3863ef31 BP	92	config CRC32_SELFTEST
	93	bool "CRC32 perform self test on init"
	94	default n
	95	depends on CRC32
	96	help
	97	This option enables the CRC32 library functions to perform a
	98	self test on initialization. The self test computes crc32_le
	99	and crc32_be over byte strings with random alignment and length
	100	and computes the total elapsed time and number of bytes processed.
	101
5cde7656 DW	102	choice
	103	prompt "CRC32 implementation"
	104	depends on CRC32
	105	default CRC32_SLICEBY8
82edb4ba DW	106	help
	107	This option allows a kernel builder to override the default choice
	108	of CRC32 algorithm. Choose the default ("slice by 8") unless you
	109	know that you need one of the others.
5cde7656 DW	110
	111	config CRC32_SLICEBY8
	112	bool "Slice by 8 bytes"
	113	help
	114	Calculate checksum 8 bytes at a time with a clever slicing algorithm.
	115	This is the fastest algorithm, but comes with a 8KiB lookup table.
	116	Most modern processors have enough cache to hold this table without
	117	thrashing the cache.
	118
	119	This is the default implementation choice. Choose this one unless
	120	you have a good reason not to.
	121
	122	config CRC32_SLICEBY4
	123	bool "Slice by 4 bytes"
	124	help
	125	Calculate checksum 4 bytes at a time with a clever slicing algorithm.
	126	This is a bit slower than slice by 8, but has a smaller 4KiB lookup
	127	table.
	128
	129	Only choose this option if you know what you are doing.
	130
	131	config CRC32_SARWATE
	132	bool "Sarwate's Algorithm (one byte at a time)"
	133	help
	134	Calculate checksum a byte at a time using Sarwate's algorithm. This
	135	is not particularly fast, but has a small 256 byte lookup table.
	136
	137	Only choose this option if you know what you are doing.
	138
	139	config CRC32_BIT
	140	bool "Classic Algorithm (one bit at a time)"
	141	help
	142	Calculate checksum one bit at a time. This is VERY slow, but has
	143	no lookup table. This is provided as a debugging option.
	144
	145	Only choose this option if you are debugging crc32.
	146
	147	endchoice
	148
ad241528 JN	149	config CRC7
	150	tristate "CRC7 functions"
	151	help
	152	This option is provided for the case where no in-kernel-tree
	153	modules require CRC7 functions, but a module built outside
	154	the kernel tree does. Such modules that use library CRC7
	155	functions require M here.
	156
1da177e4 LT	157	config LIBCRC32C
1da177e4 LT	158	tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check"
93027354	159	select CRYPTO
69c35efc	160	select CRYPTO_CRC32C
1da177e4 LT	161	help
	162	This option is provided for the case where no in-kernel-tree
	163	modules require CRC32c functions, but a module built outside the
	164	kernel tree does. Such modules that use library CRC32c functions
	165	require M here. See Castagnoli93.
	166	Module will be libcrc32c.
	167
7150962d AS	168	config CRC8
	169	tristate "CRC8 function"
	170	help
	171	This option provides CRC8 function. Drivers may select this
	172	when they need to do cyclic redundancy check according CRC8
	173	algorithm. Module will be called crc8.
	174
e65e1fc2 AV	175	config AUDIT_GENERIC
	176	bool
	177	depends on AUDIT && !AUDIT_ARCH
	178	default y
	179
1da177e4 LT	180	#
	181	# compression support is select'ed if needed
	182	#
	183	config ZLIB_INFLATE
	184	tristate
	185
	186	config ZLIB_DEFLATE
	187	tristate
	188
64c70b1c RP	189	config LZO_COMPRESS
	190	tristate
	191
	192	config LZO_DECOMPRESS
	193	tristate
	194
c72ac7a1 CM	195	config LZ4_COMPRESS
	196	tristate
	197
	198	config LZ4HC_COMPRESS
	199	tristate
	200
e76e1fdf KL	201	config LZ4_DECOMPRESS
	202	tristate
	203
24fa0402 LC	204	source "lib/xz/Kconfig"
24fa0402 LC	205
c8531ab3 PA	206	#
	207	# These all provide a common interface (hence the apparent duplication with
	208	# ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.)
	209	#
	210	config DECOMPRESS_GZIP
7856a16e	211	select ZLIB_INFLATE
c8531ab3 PA	212	tristate
	213
	214	config DECOMPRESS_BZIP2
	215	tristate
	216
	217	config DECOMPRESS_LZMA
	218	tristate
	219
3ebe1243 LC	220	config DECOMPRESS_XZ
	221	select XZ_DEC
	222	tristate
	223
cacb246f AT	224	config DECOMPRESS_LZO
	225	select LZO_DECOMPRESS
	226	tristate
	227
e76e1fdf KL	228	config DECOMPRESS_LZ4
	229	select LZ4_DECOMPRESS
	230	tristate
	231
f14f75b8 JS	232	#
	233	# Generic allocator support is selected if needed
	234	#
	235	config GENERIC_ALLOCATOR
	236	boolean
	237
1da177e4 LT	238	#
	239	# reed solomon support is select'ed if needed
	240	#
	241	config REED_SOLOMON
	242	tristate
	243
	244	config REED_SOLOMON_ENC8
	245	boolean
	246
	247	config REED_SOLOMON_DEC8
	248	boolean
	249
	250	config REED_SOLOMON_ENC16
	251	boolean
	252
	253	config REED_SOLOMON_DEC16
	254	boolean
	255
437aa565 ID	256	#
	257	# BCH support is selected if needed
	258	#
	259	config BCH
	260	tristate
	261
	262	config BCH_CONST_PARAMS
	263	boolean
	264	help
	265	Drivers may select this option to force specific constant
	266	values for parameters 'm' (Galois field order) and 't'
	267	(error correction capability). Those specific values must
	268	be set by declaring default values for symbols BCH_CONST_M
	269	and BCH_CONST_T.
	270	Doing so will enable extra compiler optimizations,
	271	improving encoding and decoding performance up to 2x for
	272	usual (m,t) values (typically such that m*t < 200).
	273	When this option is selected, the BCH library supports
	274	only a single (m,t) configuration. This is mainly useful
	275	for NAND flash board drivers requiring known, fixed BCH
	276	parameters.
	277
	278	config BCH_CONST_M
	279	int
	280	range 5 15
	281	help
	282	Constant value for Galois field order 'm'. If 'k' is the
	283	number of data bits to protect, 'm' should be chosen such
	284	that (k + mt) <= 2*m - 1.
	285	Drivers should declare a default value for this symbol if
	286	they select option BCH_CONST_PARAMS.
	287
	288	config BCH_CONST_T
	289	int
	290	help
	291	Constant value for error correction capability in bits 't'.
	292	Drivers should declare a default value for this symbol if
	293	they select option BCH_CONST_PARAMS.
	294
f7704347 DM	295	#
	296	# Textsearch support is select'ed if needed
	297	#
2de4ff7b	298	config TEXTSEARCH
f7704347	299	boolean
1da177e4	300
df3fb93a	301	config TEXTSEARCH_KMP
f7704347	302	tristate
df3fb93a	303
8082e4ed	304	config TEXTSEARCH_BM
29cb9f9c	305	tristate
8082e4ed	306
6408f79c	307	config TEXTSEARCH_FSM
f7704347	308	tristate
6408f79c	309
5db53f3e JE	310	config BTREE
	311	boolean
	312
5ea81769	313	config HAS_IOMEM
ee36c2bf	314	boolean
5ea81769	315	depends on !NO_IOMEM
087fafd1	316	select GENERIC_IO
5ea81769 AV	317	default y
	318
	319	config HAS_IOPORT
	320	boolean
	321	depends on HAS_IOMEM && !NO_IOPORT
ee36c2bf AV	322	default y
ee36c2bf AV	323
411f0f3e HC	324	config HAS_DMA
	325	boolean
	326	depends on !NO_DMA
	327	default y
	328
928923c7 GU	329	config CHECK_SIGNATURE
	330	bool
	331
aab46da0 RR	332	config CPUMASK_OFFSTACK
	333	bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
	334	help
	335	Use dynamic allocation for cpumask_var_t, instead of putting
	336	them on the stack. This is a bit more expensive, but avoids
	337	stack overflow.
	338
8c384cde RR	339	config DISABLE_OBSOLETE_CPUMASK_FUNCTIONS
8c384cde RR	340	bool "Disable obsolete cpumask functions" if DEBUG_PER_CPU_MAPS
525c1f92	341	depends on BROKEN
8c384cde	342
c39649c3 BH	343	config CPU_RMAP
	344	bool
	345	depends on SMP
	346
75957ba3 TH	347	config DQL
	348	bool
	349
e9cc8bdd GU	350	#
	351	# Netlink attribute parsing support is select'ed if needed
	352	#
	353	config NLATTR
	354	bool
	355
09d4e0ed PM	356	#
	357	# Generic 64-bit atomic support is selected if needed
	358	#
	359	config GENERIC_ATOMIC64
	360	bool
	361
7463449b CM	362	config ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
	363	def_bool y if GENERIC_ATOMIC64
	364
b411b363 PR	365	config LRU_CACHE
	366	tristate
	367
c5485a7e	368	config AVERAGE
a7a9a24d MB	369	bool "Averaging functions"
	370	help
	371	This option is provided for the case where no in-kernel-tree
	372	modules require averaging functions, but a module built outside
	373	the kernel tree does. Such modules that use library averaging
	374	functions require Y here.
	375
	376	If unsure, say N.
c5485a7e	377
c6df4b17 DM	378	config CLZ_TAB
	379	bool
	380
10f8113e	381	config CORDIC
d89ce936	382	tristate "CORDIC algorithm"
10f8113e	383	help
435a95c5 MW	384	This option provides an implementation of the CORDIC algorithm;
435a95c5 MW	385	calculations are in fixed point. Module will be called cordic.
10f8113e	386
9c1c21a0 A	387	config DDR
	388	bool "JEDEC DDR data"
	389	help
	390	Data from JEDEC specs for DDR SDRAM memories,
	391	particularly the AC timing parameters and addressing
	392	information. This data is useful for drivers handling
	393	DDR SDRAM controllers.
	394
d9c46b18	395	config MPILIB
2e5f094b	396	tristate
c6df4b17	397	select CLZ_TAB
d9c46b18 DK	398	help
	399	Multiprecision maths library from GnuPG.
	400	It is used to implement RSA digital signature verification,
	401	which is used by IMA/EVM digital signature extension.
	402
5e8898e9	403	config SIGNATURE
2e5f094b	404	tristate
be440ec7 DK	405	depends on KEYS && CRYPTO
be440ec7 DK	406	select CRYPTO_SHA1
051dbb91 DK	407	select MPILIB
	408	help
	409	Digital signature verification. Currently only RSA is supported.
	410	Implementation is done using GnuPG MPI library
	411
ab253839 DD	412	#
	413	# libfdt files, only selected if needed.
	414	#
	415	config LIBFDT
	416	bool
	417
a77ad6ea DH	418	config OID_REGISTRY
	419	tristate
	420	help
	421	Enable fast lookup object identifier registry.
	422
0635eb8a MG	423	config UCS2_STRING
	424	tristate
	425
ee89bd6b GU	426	source "lib/fonts/Kconfig"
ee89bd6b GU	427
2de4ff7b	428	endmenu