2 # Library configuration
8 menu "Library routines"
19 config GENERIC_STRNCPY_FROM_USER
22 config GENERIC_STRNLEN_USER
25 config GENERIC_FIND_FIRST_BIT
28 config NO_GENERIC_PCI_IOPORT_MAP
31 config GENERIC_PCI_IOMAP
36 select GENERIC_PCI_IOMAP
49 tristate "CRC-CCITT functions"
51 This option is provided for the case where no in-kernel-tree
52 modules require CRC-CCITT functions, but a module built outside
53 the kernel tree does. Such modules that use library CRC-CCITT
54 functions require M here.
57 tristate "CRC16 functions"
59 This option is provided for the case where no in-kernel-tree
60 modules require CRC16 functions, but a module built outside
61 the kernel tree does. Such modules that use library CRC16
62 functions require M here.
65 tristate "CRC calculation for the T10 Data Integrity Field"
67 select CRYPTO_CRCT10DIF
69 This option is only needed if a module that's not in the
70 kernel tree needs to calculate CRC checks for use with the
71 SCSI data integrity subsystem.
74 tristate "CRC ITU-T V.41 functions"
76 This option is provided for the case where no in-kernel-tree
77 modules require CRC ITU-T V.41 functions, but a module built outside
78 the kernel tree does. Such modules that use library CRC ITU-T V.41
79 functions require M here.
82 tristate "CRC32/CRC32c functions"
86 This option is provided for the case where no in-kernel-tree
87 modules require CRC32/CRC32c functions, but a module built outside
88 the kernel tree does. Such modules that use library CRC32/CRC32c
89 functions require M here.
92 bool "CRC32 perform self test on init"
96 This option enables the CRC32 library functions to perform a
97 self test on initialization. The self test computes crc32_le
98 and crc32_be over byte strings with random alignment and length
99 and computes the total elapsed time and number of bytes processed.
102 prompt "CRC32 implementation"
104 default CRC32_SLICEBY8
106 This option allows a kernel builder to override the default choice
107 of CRC32 algorithm. Choose the default ("slice by 8") unless you
108 know that you need one of the others.
110 config CRC32_SLICEBY8
111 bool "Slice by 8 bytes"
113 Calculate checksum 8 bytes at a time with a clever slicing algorithm.
114 This is the fastest algorithm, but comes with a 8KiB lookup table.
115 Most modern processors have enough cache to hold this table without
118 This is the default implementation choice. Choose this one unless
119 you have a good reason not to.
121 config CRC32_SLICEBY4
122 bool "Slice by 4 bytes"
124 Calculate checksum 4 bytes at a time with a clever slicing algorithm.
125 This is a bit slower than slice by 8, but has a smaller 4KiB lookup
128 Only choose this option if you know what you are doing.
131 bool "Sarwate's Algorithm (one byte at a time)"
133 Calculate checksum a byte at a time using Sarwate's algorithm. This
134 is not particularly fast, but has a small 256 byte lookup table.
136 Only choose this option if you know what you are doing.
139 bool "Classic Algorithm (one bit at a time)"
141 Calculate checksum one bit at a time. This is VERY slow, but has
142 no lookup table. This is provided as a debugging option.
144 Only choose this option if you are debugging crc32.
149 tristate "CRC7 functions"
151 This option is provided for the case where no in-kernel-tree
152 modules require CRC7 functions, but a module built outside
153 the kernel tree does. Such modules that use library CRC7
154 functions require M here.
157 tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check"
161 This option is provided for the case where no in-kernel-tree
162 modules require CRC32c functions, but a module built outside the
163 kernel tree does. Such modules that use library CRC32c functions
164 require M here. See Castagnoli93.
165 Module will be libcrc32c.
168 tristate "CRC8 function"
170 This option provides CRC8 function. Drivers may select this
171 when they need to do cyclic redundancy check according CRC8
172 algorithm. Module will be called crc8.
176 depends on AUDIT && !AUDIT_ARCH
180 # compression support is select'ed if needed
191 config LZO_DECOMPRESS
194 source "lib/xz/Kconfig"
197 # These all provide a common interface (hence the apparent duplication with
198 # ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.)
200 config DECOMPRESS_GZIP
204 config DECOMPRESS_BZIP2
207 config DECOMPRESS_LZMA
214 config DECOMPRESS_LZO
215 select LZO_DECOMPRESS
219 # Generic allocator support is selected if needed
221 config GENERIC_ALLOCATOR
225 # reed solomon support is select'ed if needed
230 config REED_SOLOMON_ENC8
233 config REED_SOLOMON_DEC8
236 config REED_SOLOMON_ENC16
239 config REED_SOLOMON_DEC16
243 # BCH support is selected if needed
248 config BCH_CONST_PARAMS
251 Drivers may select this option to force specific constant
252 values for parameters 'm' (Galois field order) and 't'
253 (error correction capability). Those specific values must
254 be set by declaring default values for symbols BCH_CONST_M
256 Doing so will enable extra compiler optimizations,
257 improving encoding and decoding performance up to 2x for
258 usual (m,t) values (typically such that m*t < 200).
259 When this option is selected, the BCH library supports
260 only a single (m,t) configuration. This is mainly useful
261 for NAND flash board drivers requiring known, fixed BCH
268 Constant value for Galois field order 'm'. If 'k' is the
269 number of data bits to protect, 'm' should be chosen such
270 that (k + m*t) <= 2**m - 1.
271 Drivers should declare a default value for this symbol if
272 they select option BCH_CONST_PARAMS.
277 Constant value for error correction capability in bits 't'.
278 Drivers should declare a default value for this symbol if
279 they select option BCH_CONST_PARAMS.
282 # Textsearch support is select'ed if needed
287 config TEXTSEARCH_KMP
293 config TEXTSEARCH_FSM
307 depends on HAS_IOMEM && !NO_IOPORT
315 config CHECK_SIGNATURE
318 config CPUMASK_OFFSTACK
319 bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
321 Use dynamic allocation for cpumask_var_t, instead of putting
322 them on the stack. This is a bit more expensive, but avoids
325 config DISABLE_OBSOLETE_CPUMASK_FUNCTIONS
326 bool "Disable obsolete cpumask functions" if DEBUG_PER_CPU_MAPS
337 # Netlink attribute parsing support is select'ed if needed
343 # Generic 64-bit atomic support is selected if needed
345 config GENERIC_ATOMIC64
348 config ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
349 def_bool y if GENERIC_ATOMIC64
355 bool "Averaging functions"
357 This option is provided for the case where no in-kernel-tree
358 modules require averaging functions, but a module built outside
359 the kernel tree does. Such modules that use library averaging
360 functions require Y here.
368 tristate "CORDIC algorithm"
370 This option provides an implementation of the CORDIC algorithm;
371 calculations are in fixed point. Module will be called cordic.
374 bool "JEDEC DDR data"
376 Data from JEDEC specs for DDR SDRAM memories,
377 particularly the AC timing parameters and addressing
378 information. This data is useful for drivers handling
379 DDR SDRAM controllers.
385 Multiprecision maths library from GnuPG.
386 It is used to implement RSA digital signature verification,
387 which is used by IMA/EVM digital signature extension.
391 depends on KEYS && CRYPTO
395 Digital signature verification. Currently only RSA is supported.
396 Implementation is done using GnuPG MPI library
399 # libfdt files, only selected if needed.
407 Enable fast lookup object identifier registry.