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 This option is only needed if a module that's not in the
81 kernel tree needs to calculate CRC checks for use with the
82 SCSI data integrity subsystem.
85 tristate "CRC ITU-T V.41 functions"
87 This option is provided for the case where no in-kernel-tree
88 modules require CRC ITU-T V.41 functions, but a module built outside
89 the kernel tree does. Such modules that use library CRC ITU-T V.41
90 functions require M here.
93 tristate "CRC32/CRC32c functions"
97 This option is provided for the case where no in-kernel-tree
98 modules require CRC32/CRC32c functions, but a module built outside
99 the kernel tree does. Such modules that use library CRC32/CRC32c
100 functions require M here.
102 config CRC32_SELFTEST
103 bool "CRC32 perform self test on init"
107 This option enables the CRC32 library functions to perform a
108 self test on initialization. The self test computes crc32_le
109 and crc32_be over byte strings with random alignment and length
110 and computes the total elapsed time and number of bytes processed.
113 prompt "CRC32 implementation"
115 default CRC32_SLICEBY8
117 This option allows a kernel builder to override the default choice
118 of CRC32 algorithm. Choose the default ("slice by 8") unless you
119 know that you need one of the others.
121 config CRC32_SLICEBY8
122 bool "Slice by 8 bytes"
124 Calculate checksum 8 bytes at a time with a clever slicing algorithm.
125 This is the fastest algorithm, but comes with a 8KiB lookup table.
126 Most modern processors have enough cache to hold this table without
129 This is the default implementation choice. Choose this one unless
130 you have a good reason not to.
132 config CRC32_SLICEBY4
133 bool "Slice by 4 bytes"
135 Calculate checksum 4 bytes at a time with a clever slicing algorithm.
136 This is a bit slower than slice by 8, but has a smaller 4KiB lookup
139 Only choose this option if you know what you are doing.
142 bool "Sarwate's Algorithm (one byte at a time)"
144 Calculate checksum a byte at a time using Sarwate's algorithm. This
145 is not particularly fast, but has a small 256 byte lookup table.
147 Only choose this option if you know what you are doing.
150 bool "Classic Algorithm (one bit at a time)"
152 Calculate checksum one bit at a time. This is VERY slow, but has
153 no lookup table. This is provided as a debugging option.
155 Only choose this option if you are debugging crc32.
160 tristate "CRC7 functions"
162 This option is provided for the case where no in-kernel-tree
163 modules require CRC7 functions, but a module built outside
164 the kernel tree does. Such modules that use library CRC7
165 functions require M here.
168 tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check"
172 This option is provided for the case where no in-kernel-tree
173 modules require CRC32c functions, but a module built outside the
174 kernel tree does. Such modules that use library CRC32c functions
175 require M here. See Castagnoli93.
176 Module will be libcrc32c.
179 tristate "CRC8 function"
181 This option provides CRC8 function. Drivers may select this
182 when they need to do cyclic redundancy check according CRC8
183 algorithm. Module will be called crc8.
187 depends on AUDIT && !AUDIT_ARCH
191 # compression support is select'ed if needed
202 config LZO_DECOMPRESS
208 config LZ4HC_COMPRESS
211 config LZ4_DECOMPRESS
214 source "lib/xz/Kconfig"
217 # These all provide a common interface (hence the apparent duplication with
218 # ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.)
220 config DECOMPRESS_GZIP
224 config DECOMPRESS_BZIP2
227 config DECOMPRESS_LZMA
234 config DECOMPRESS_LZO
235 select LZO_DECOMPRESS
238 config DECOMPRESS_LZ4
239 select LZ4_DECOMPRESS
243 # Generic allocator support is selected if needed
245 config GENERIC_ALLOCATOR
249 # reed solomon support is select'ed if needed
254 config REED_SOLOMON_ENC8
257 config REED_SOLOMON_DEC8
260 config REED_SOLOMON_ENC16
263 config REED_SOLOMON_DEC16
267 # BCH support is selected if needed
272 config BCH_CONST_PARAMS
275 Drivers may select this option to force specific constant
276 values for parameters 'm' (Galois field order) and 't'
277 (error correction capability). Those specific values must
278 be set by declaring default values for symbols BCH_CONST_M
280 Doing so will enable extra compiler optimizations,
281 improving encoding and decoding performance up to 2x for
282 usual (m,t) values (typically such that m*t < 200).
283 When this option is selected, the BCH library supports
284 only a single (m,t) configuration. This is mainly useful
285 for NAND flash board drivers requiring known, fixed BCH
292 Constant value for Galois field order 'm'. If 'k' is the
293 number of data bits to protect, 'm' should be chosen such
294 that (k + m*t) <= 2**m - 1.
295 Drivers should declare a default value for this symbol if
296 they select option BCH_CONST_PARAMS.
301 Constant value for error correction capability in bits 't'.
302 Drivers should declare a default value for this symbol if
303 they select option BCH_CONST_PARAMS.
306 # Textsearch support is select'ed if needed
311 config TEXTSEARCH_KMP
317 config TEXTSEARCH_FSM
331 depends on HAS_IOMEM && !NO_IOPORT
339 config CHECK_SIGNATURE
342 config CPUMASK_OFFSTACK
343 bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
345 Use dynamic allocation for cpumask_var_t, instead of putting
346 them on the stack. This is a bit more expensive, but avoids
349 config DISABLE_OBSOLETE_CPUMASK_FUNCTIONS
350 bool "Disable obsolete cpumask functions" if DEBUG_PER_CPU_MAPS
361 # Netlink attribute parsing support is select'ed if needed
367 # Generic 64-bit atomic support is selected if needed
369 config GENERIC_ATOMIC64
372 config ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
373 def_bool y if GENERIC_ATOMIC64
379 bool "Averaging functions"
381 This option is provided for the case where no in-kernel-tree
382 modules require averaging functions, but a module built outside
383 the kernel tree does. Such modules that use library averaging
384 functions require Y here.
392 tristate "CORDIC algorithm"
394 This option provides an implementation of the CORDIC algorithm;
395 calculations are in fixed point. Module will be called cordic.
398 bool "JEDEC DDR data"
400 Data from JEDEC specs for DDR SDRAM memories,
401 particularly the AC timing parameters and addressing
402 information. This data is useful for drivers handling
403 DDR SDRAM controllers.
409 Multiprecision maths library from GnuPG.
410 It is used to implement RSA digital signature verification,
411 which is used by IMA/EVM digital signature extension.
415 depends on KEYS && CRYPTO
419 Digital signature verification. Currently only RSA is supported.
420 Implementation is done using GnuPG MPI library
423 # libfdt files, only selected if needed.
431 Enable fast lookup object identifier registry.
436 source "lib/fonts/Kconfig"