2 # Library configuration
8 menu "Library routines"
19 config GENERIC_STRNCPY_FROM_USER
22 config GENERIC_STRNLEN_USER
25 config GENERIC_NET_UTILS
28 config GENERIC_FIND_FIRST_BIT
31 config NO_GENERIC_PCI_IOPORT_MAP
34 config GENERIC_PCI_IOMAP
39 select GENERIC_PCI_IOMAP
51 config ARCH_USE_CMPXCHG_LOCKREF
54 config CMPXCHG_LOCKREF
55 def_bool y if ARCH_USE_CMPXCHG_LOCKREF
57 depends on !GENERIC_LOCKBREAK
58 depends on !DEBUG_SPINLOCK
59 depends on !DEBUG_LOCK_ALLOC
62 tristate "CRC-CCITT functions"
64 This option is provided for the case where no in-kernel-tree
65 modules require CRC-CCITT functions, but a module built outside
66 the kernel tree does. Such modules that use library CRC-CCITT
67 functions require M here.
70 tristate "CRC16 functions"
72 This option is provided for the case where no in-kernel-tree
73 modules require CRC16 functions, but a module built outside
74 the kernel tree does. Such modules that use library CRC16
75 functions require M here.
78 tristate "CRC calculation for the T10 Data Integrity Field"
80 select CRYPTO_CRCT10DIF
82 This option is only needed if a module that's not in the
83 kernel tree needs to calculate CRC checks for use with the
84 SCSI data integrity subsystem.
87 tristate "CRC ITU-T V.41 functions"
89 This option is provided for the case where no in-kernel-tree
90 modules require CRC ITU-T V.41 functions, but a module built outside
91 the kernel tree does. Such modules that use library CRC ITU-T V.41
92 functions require M here.
95 tristate "CRC32/CRC32c functions"
99 This option is provided for the case where no in-kernel-tree
100 modules require CRC32/CRC32c functions, but a module built outside
101 the kernel tree does. Such modules that use library CRC32/CRC32c
102 functions require M here.
104 config CRC32_SELFTEST
105 bool "CRC32 perform self test on init"
109 This option enables the CRC32 library functions to perform a
110 self test on initialization. The self test computes crc32_le
111 and crc32_be over byte strings with random alignment and length
112 and computes the total elapsed time and number of bytes processed.
115 prompt "CRC32 implementation"
117 default CRC32_SLICEBY8
119 This option allows a kernel builder to override the default choice
120 of CRC32 algorithm. Choose the default ("slice by 8") unless you
121 know that you need one of the others.
123 config CRC32_SLICEBY8
124 bool "Slice by 8 bytes"
126 Calculate checksum 8 bytes at a time with a clever slicing algorithm.
127 This is the fastest algorithm, but comes with a 8KiB lookup table.
128 Most modern processors have enough cache to hold this table without
131 This is the default implementation choice. Choose this one unless
132 you have a good reason not to.
134 config CRC32_SLICEBY4
135 bool "Slice by 4 bytes"
137 Calculate checksum 4 bytes at a time with a clever slicing algorithm.
138 This is a bit slower than slice by 8, but has a smaller 4KiB lookup
141 Only choose this option if you know what you are doing.
144 bool "Sarwate's Algorithm (one byte at a time)"
146 Calculate checksum a byte at a time using Sarwate's algorithm. This
147 is not particularly fast, but has a small 256 byte lookup table.
149 Only choose this option if you know what you are doing.
152 bool "Classic Algorithm (one bit at a time)"
154 Calculate checksum one bit at a time. This is VERY slow, but has
155 no lookup table. This is provided as a debugging option.
157 Only choose this option if you are debugging crc32.
162 tristate "CRC7 functions"
164 This option is provided for the case where no in-kernel-tree
165 modules require CRC7 functions, but a module built outside
166 the kernel tree does. Such modules that use library CRC7
167 functions require M here.
170 tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check"
174 This option is provided for the case where no in-kernel-tree
175 modules require CRC32c functions, but a module built outside the
176 kernel tree does. Such modules that use library CRC32c functions
177 require M here. See Castagnoli93.
178 Module will be libcrc32c.
181 tristate "CRC8 function"
183 This option provides CRC8 function. Drivers may select this
184 when they need to do cyclic redundancy check according CRC8
185 algorithm. Module will be called crc8.
189 depends on AUDIT && !AUDIT_ARCH
192 config RANDOM32_SELFTEST
193 bool "PRNG perform self test on init"
196 This option enables the 32 bit PRNG library functions to perform a
197 self test on initialization.
200 # compression support is select'ed if needed
211 config LZO_DECOMPRESS
217 config LZ4HC_COMPRESS
220 config LZ4_DECOMPRESS
223 source "lib/xz/Kconfig"
226 # These all provide a common interface (hence the apparent duplication with
227 # ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.)
229 config DECOMPRESS_GZIP
233 config DECOMPRESS_BZIP2
236 config DECOMPRESS_LZMA
243 config DECOMPRESS_LZO
244 select LZO_DECOMPRESS
247 config DECOMPRESS_LZ4
248 select LZ4_DECOMPRESS
252 # Generic allocator support is selected if needed
254 config GENERIC_ALLOCATOR
258 # reed solomon support is select'ed if needed
263 config REED_SOLOMON_ENC8
266 config REED_SOLOMON_DEC8
269 config REED_SOLOMON_ENC16
272 config REED_SOLOMON_DEC16
276 # BCH support is selected if needed
281 config BCH_CONST_PARAMS
284 Drivers may select this option to force specific constant
285 values for parameters 'm' (Galois field order) and 't'
286 (error correction capability). Those specific values must
287 be set by declaring default values for symbols BCH_CONST_M
289 Doing so will enable extra compiler optimizations,
290 improving encoding and decoding performance up to 2x for
291 usual (m,t) values (typically such that m*t < 200).
292 When this option is selected, the BCH library supports
293 only a single (m,t) configuration. This is mainly useful
294 for NAND flash board drivers requiring known, fixed BCH
301 Constant value for Galois field order 'm'. If 'k' is the
302 number of data bits to protect, 'm' should be chosen such
303 that (k + m*t) <= 2**m - 1.
304 Drivers should declare a default value for this symbol if
305 they select option BCH_CONST_PARAMS.
310 Constant value for error correction capability in bits 't'.
311 Drivers should declare a default value for this symbol if
312 they select option BCH_CONST_PARAMS.
315 # Textsearch support is select'ed if needed
320 config TEXTSEARCH_KMP
326 config TEXTSEARCH_FSM
340 depends on HAS_IOMEM && !NO_IOPORT
348 config CHECK_SIGNATURE
351 config CPUMASK_OFFSTACK
352 bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
354 Use dynamic allocation for cpumask_var_t, instead of putting
355 them on the stack. This is a bit more expensive, but avoids
358 config DISABLE_OBSOLETE_CPUMASK_FUNCTIONS
359 bool "Disable obsolete cpumask functions" if DEBUG_PER_CPU_MAPS
370 # Netlink attribute parsing support is select'ed if needed
376 # Generic 64-bit atomic support is selected if needed
378 config GENERIC_ATOMIC64
381 config ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
382 def_bool y if GENERIC_ATOMIC64
388 bool "Averaging functions"
390 This option is provided for the case where no in-kernel-tree
391 modules require averaging functions, but a module built outside
392 the kernel tree does. Such modules that use library averaging
393 functions require Y here.
401 tristate "CORDIC algorithm"
403 This option provides an implementation of the CORDIC algorithm;
404 calculations are in fixed point. Module will be called cordic.
407 bool "JEDEC DDR data"
409 Data from JEDEC specs for DDR SDRAM memories,
410 particularly the AC timing parameters and addressing
411 information. This data is useful for drivers handling
412 DDR SDRAM controllers.
418 Multiprecision maths library from GnuPG.
419 It is used to implement RSA digital signature verification,
420 which is used by IMA/EVM digital signature extension.
424 depends on KEYS && CRYPTO
428 Digital signature verification. Currently only RSA is supported.
429 Implementation is done using GnuPG MPI library
432 # libfdt files, only selected if needed.
440 Enable fast lookup object identifier registry.
445 source "lib/fonts/Kconfig"