1 #
2 # Library configuration
3 #
5 config BINARY_PRINTF
6 def_bool n
8 menu "Library routines"
10 config RAID6_PQ
11 tristate
13 config BITREVERSE
14 tristate
16 config HAVE_ARCH_BITREVERSE
17 bool
18 default n
19 depends on BITREVERSE
20 help
21 This option enables the use of hardware bit-reversal instructions on
22 architectures which support such operations.
24 config RATIONAL
25 bool
27 config GENERIC_STRNCPY_FROM_USER
28 bool
30 config GENERIC_STRNLEN_USER
31 bool
33 config GENERIC_NET_UTILS
34 bool
36 config GENERIC_FIND_FIRST_BIT
37 bool
39 config NO_GENERIC_PCI_IOPORT_MAP
40 bool
42 config GENERIC_PCI_IOMAP
43 bool
45 config GENERIC_IOMAP
46 bool
47 select GENERIC_PCI_IOMAP
49 config STMP_DEVICE
50 bool
52 config ARCH_USE_CMPXCHG_LOCKREF
53 bool
55 config ARCH_HAS_FAST_MULTIPLIER
56 bool
58 config INDIRECT_PIO
59 bool "Access I/O in non-MMIO mode"
60 depends on ARM64
61 help
62 On some platforms where no separate I/O space exists, there are I/O
63 hosts which can not be accessed in MMIO mode. Using the logical PIO
64 mechanism, the host-local I/O resource can be mapped into system
65 logic PIO space shared with MMIO hosts, such as PCI/PCIe, then the
66 system can access the I/O devices with the mapped-logic PIO through
67 I/O accessors.
69 This way has relatively little I/O performance cost. Please make
70 sure your devices really need this configure item enabled.
72 When in doubt, say N.
74 config CRC_CCITT
75 tristate "CRC-CCITT functions"
76 help
77 This option is provided for the case where no in-kernel-tree
78 modules require CRC-CCITT functions, but a module built outside
79 the kernel tree does. Such modules that use library CRC-CCITT
80 functions require M here.
82 config CRC16
83 tristate "CRC16 functions"
84 help
85 This option is provided for the case where no in-kernel-tree
86 modules require CRC16 functions, but a module built outside
87 the kernel tree does. Such modules that use library CRC16
88 functions require M here.
90 config CRC_T10DIF
91 tristate "CRC calculation for the T10 Data Integrity Field"
92 select CRYPTO
93 select CRYPTO_CRCT10DIF
94 help
95 This option is only needed if a module that's not in the
96 kernel tree needs to calculate CRC checks for use with the
97 SCSI data integrity subsystem.
99 config CRC_ITU_T
100 tristate "CRC ITU-T V.41 functions"
101 help
102 This option is provided for the case where no in-kernel-tree
103 modules require CRC ITU-T V.41 functions, but a module built outside
104 the kernel tree does. Such modules that use library CRC ITU-T V.41
105 functions require M here.
107 config CRC32
108 tristate "CRC32/CRC32c functions"
109 default y
110 select BITREVERSE
111 help
112 This option is provided for the case where no in-kernel-tree
113 modules require CRC32/CRC32c functions, but a module built outside
114 the kernel tree does. Such modules that use library CRC32/CRC32c
115 functions require M here.
117 config CRC32_SELFTEST
118 tristate "CRC32 perform self test on init"
119 depends on CRC32
120 help
121 This option enables the CRC32 library functions to perform a
122 self test on initialization. The self test computes crc32_le
123 and crc32_be over byte strings with random alignment and length
124 and computes the total elapsed time and number of bytes processed.
126 choice
127 prompt "CRC32 implementation"
128 depends on CRC32
129 default CRC32_SLICEBY8
130 help
131 This option allows a kernel builder to override the default choice
132 of CRC32 algorithm. Choose the default ("slice by 8") unless you
133 know that you need one of the others.
135 config CRC32_SLICEBY8
136 bool "Slice by 8 bytes"
137 help
138 Calculate checksum 8 bytes at a time with a clever slicing algorithm.
139 This is the fastest algorithm, but comes with a 8KiB lookup table.
140 Most modern processors have enough cache to hold this table without
141 thrashing the cache.
143 This is the default implementation choice. Choose this one unless
144 you have a good reason not to.
146 config CRC32_SLICEBY4
147 bool "Slice by 4 bytes"
148 help
149 Calculate checksum 4 bytes at a time with a clever slicing algorithm.
150 This is a bit slower than slice by 8, but has a smaller 4KiB lookup
151 table.
153 Only choose this option if you know what you are doing.
155 config CRC32_SARWATE
156 bool "Sarwate's Algorithm (one byte at a time)"
157 help
158 Calculate checksum a byte at a time using Sarwate's algorithm. This
159 is not particularly fast, but has a small 256 byte lookup table.
161 Only choose this option if you know what you are doing.
163 config CRC32_BIT
164 bool "Classic Algorithm (one bit at a time)"
165 help
166 Calculate checksum one bit at a time. This is VERY slow, but has
167 no lookup table. This is provided as a debugging option.
169 Only choose this option if you are debugging crc32.
171 endchoice
173 config CRC64
174 tristate "CRC64 functions"
175 help
176 This option is provided for the case where no in-kernel-tree
177 modules require CRC64 functions, but a module built outside
178 the kernel tree does. Such modules that use library CRC64
179 functions require M here.
181 config CRC4
182 tristate "CRC4 functions"
183 help
184 This option is provided for the case where no in-kernel-tree
185 modules require CRC4 functions, but a module built outside
186 the kernel tree does. Such modules that use library CRC4
187 functions require M here.
189 config CRC7
190 tristate "CRC7 functions"
191 help
192 This option is provided for the case where no in-kernel-tree
193 modules require CRC7 functions, but a module built outside
194 the kernel tree does. Such modules that use library CRC7
195 functions require M here.
197 config LIBCRC32C
198 tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check"
199 select CRYPTO
200 select CRYPTO_CRC32C
201 help
202 This option is provided for the case where no in-kernel-tree
203 modules require CRC32c functions, but a module built outside the
204 kernel tree does. Such modules that use library CRC32c functions
205 require M here. See Castagnoli93.
206 Module will be libcrc32c.
208 config CRC8
209 tristate "CRC8 function"
210 help
211 This option provides CRC8 function. Drivers may select this
212 when they need to do cyclic redundancy check according CRC8
213 algorithm. Module will be called crc8.
215 config XXHASH
216 tristate
218 config AUDIT_GENERIC
219 bool
220 depends on AUDIT && !AUDIT_ARCH
221 default y
223 config AUDIT_ARCH_COMPAT_GENERIC
224 bool
225 default n
227 config AUDIT_COMPAT_GENERIC
228 bool
229 depends on AUDIT_GENERIC && AUDIT_ARCH_COMPAT_GENERIC && COMPAT
230 default y
232 config RANDOM32_SELFTEST
233 bool "PRNG perform self test on init"
234 help
235 This option enables the 32 bit PRNG library functions to perform a
236 self test on initialization.
238 #
239 # compression support is select'ed if needed
240 #
241 config 842_COMPRESS
242 select CRC32
243 tristate
245 config 842_DECOMPRESS
246 select CRC32
247 tristate
249 config ZLIB_INFLATE
250 tristate
252 config ZLIB_DEFLATE
253 tristate
254 select BITREVERSE
256 config LZO_COMPRESS
257 tristate
259 config LZO_DECOMPRESS
260 tristate
262 config LZ4_COMPRESS
263 tristate
265 config LZ4HC_COMPRESS
266 tristate
268 config LZ4_DECOMPRESS
269 tristate
271 config ZSTD_COMPRESS
272 select XXHASH
273 tristate
275 config ZSTD_DECOMPRESS
276 select XXHASH
277 tristate
279 source "lib/xz/Kconfig"
281 #
282 # These all provide a common interface (hence the apparent duplication with
283 # ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.)
284 #
285 config DECOMPRESS_GZIP
286 select ZLIB_INFLATE
287 tristate
289 config DECOMPRESS_BZIP2
290 tristate
292 config DECOMPRESS_LZMA
293 tristate
295 config DECOMPRESS_XZ
296 select XZ_DEC
297 tristate
299 config DECOMPRESS_LZO
300 select LZO_DECOMPRESS
301 tristate
303 config DECOMPRESS_LZ4
304 select LZ4_DECOMPRESS
305 tristate
307 #
308 # Generic allocator support is selected if needed
309 #
310 config GENERIC_ALLOCATOR
311 bool
313 #
314 # reed solomon support is select'ed if needed
315 #
316 config REED_SOLOMON
317 tristate
319 config REED_SOLOMON_ENC8
320 bool
322 config REED_SOLOMON_DEC8
323 bool
325 config REED_SOLOMON_ENC16
326 bool
328 config REED_SOLOMON_DEC16
329 bool
331 #
332 # BCH support is selected if needed
333 #
334 config BCH
335 tristate
337 config BCH_CONST_PARAMS
338 bool
339 help
340 Drivers may select this option to force specific constant
341 values for parameters 'm' (Galois field order) and 't'
342 (error correction capability). Those specific values must
343 be set by declaring default values for symbols BCH_CONST_M
344 and BCH_CONST_T.
345 Doing so will enable extra compiler optimizations,
346 improving encoding and decoding performance up to 2x for
347 usual (m,t) values (typically such that m*t < 200).
348 When this option is selected, the BCH library supports
349 only a single (m,t) configuration. This is mainly useful
350 for NAND flash board drivers requiring known, fixed BCH
351 parameters.
353 config BCH_CONST_M
354 int
355 range 5 15
356 help
357 Constant value for Galois field order 'm'. If 'k' is the
358 number of data bits to protect, 'm' should be chosen such
359 that (k + m*t) <= 2**m - 1.
360 Drivers should declare a default value for this symbol if
361 they select option BCH_CONST_PARAMS.
363 config BCH_CONST_T
364 int
365 help
366 Constant value for error correction capability in bits 't'.
367 Drivers should declare a default value for this symbol if
368 they select option BCH_CONST_PARAMS.
370 #
371 # Textsearch support is select'ed if needed
372 #
373 config TEXTSEARCH
374 bool
376 config TEXTSEARCH_KMP
377 tristate
379 config TEXTSEARCH_BM
380 tristate
382 config TEXTSEARCH_FSM
383 tristate
385 config BTREE
386 bool
388 config INTERVAL_TREE
389 bool
390 help
391 Simple, embeddable, interval-tree. Can find the start of an
392 overlapping range in log(n) time and then iterate over all
393 overlapping nodes. The algorithm is implemented as an
394 augmented rbtree.
396 See:
398 Documentation/rbtree.txt
400 for more information.
402 config RADIX_TREE_MULTIORDER
403 bool
405 config ASSOCIATIVE_ARRAY
406 bool
407 help
408 Generic associative array. Can be searched and iterated over whilst
409 it is being modified. It is also reasonably quick to search and
410 modify. The algorithms are non-recursive, and the trees are highly
411 capacious.
413 See:
415 Documentation/core-api/assoc_array.rst
417 for more information.
419 config HAS_IOMEM
420 bool
421 depends on !NO_IOMEM
422 select GENERIC_IO
423 default y
425 config HAS_IOPORT_MAP
426 bool
427 depends on HAS_IOMEM && !NO_IOPORT_MAP
428 default y
430 source "kernel/dma/Kconfig"
432 config SGL_ALLOC
433 bool
434 default n
436 config IOMMU_HELPER
437 bool
439 config CHECK_SIGNATURE
440 bool
442 config CPUMASK_OFFSTACK
443 bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
444 help
445 Use dynamic allocation for cpumask_var_t, instead of putting
446 them on the stack. This is a bit more expensive, but avoids
447 stack overflow.
449 config CPU_RMAP
450 bool
451 depends on SMP
453 config DQL
454 bool
456 config GLOB
457 bool
458 # This actually supports modular compilation, but the module overhead
459 # is ridiculous for the amount of code involved. Until an out-of-tree
460 # driver asks for it, we'll just link it directly it into the kernel
461 # when required. Since we're ignoring out-of-tree users, there's also
462 # no need bother prompting for a manual decision:
463 # prompt "glob_match() function"
464 help
465 This option provides a glob_match function for performing
466 simple text pattern matching. It originated in the ATA code
467 to blacklist particular drive models, but other device drivers
468 may need similar functionality.
470 All drivers in the Linux kernel tree that require this function
471 should automatically select this option. Say N unless you
472 are compiling an out-of tree driver which tells you that it
473 depends on this.
475 config GLOB_SELFTEST
476 tristate "glob self-test on init"
477 depends on GLOB
478 help
479 This option enables a simple self-test of the glob_match
480 function on startup. It is primarily useful for people
481 working on the code to ensure they haven't introduced any
482 regressions.
484 It only adds a little bit of code and slows kernel boot (or
485 module load) by a small amount, so you're welcome to play with
486 it, but you probably don't need it.
488 #
489 # Netlink attribute parsing support is select'ed if needed
490 #
491 config NLATTR
492 bool
494 #
495 # Generic 64-bit atomic support is selected if needed
496 #
497 config GENERIC_ATOMIC64
498 bool
500 config LRU_CACHE
501 tristate
503 config CLZ_TAB
504 bool
506 config CORDIC
507 tristate "CORDIC algorithm"
508 help
509 This option provides an implementation of the CORDIC algorithm;
510 calculations are in fixed point. Module will be called cordic.
512 config DDR
513 bool "JEDEC DDR data"
514 help
515 Data from JEDEC specs for DDR SDRAM memories,
516 particularly the AC timing parameters and addressing
517 information. This data is useful for drivers handling
518 DDR SDRAM controllers.
520 config IRQ_POLL
521 bool "IRQ polling library"
522 help
523 Helper library to poll interrupt mitigation using polling.
525 config MPILIB
526 tristate
527 select CLZ_TAB
528 help
529 Multiprecision maths library from GnuPG.
530 It is used to implement RSA digital signature verification,
531 which is used by IMA/EVM digital signature extension.
533 config SIGNATURE
534 tristate
535 depends on KEYS
536 select CRYPTO
537 select CRYPTO_SHA1
538 select MPILIB
539 help
540 Digital signature verification. Currently only RSA is supported.
541 Implementation is done using GnuPG MPI library
543 #
544 # libfdt files, only selected if needed.
545 #
546 config LIBFDT
547 bool
549 config OID_REGISTRY
550 tristate
551 help
552 Enable fast lookup object identifier registry.
554 config UCS2_STRING
555 tristate
557 source "lib/fonts/Kconfig"
559 config SG_SPLIT
560 def_bool n
561 help
562 Provides a helper to split scatterlists into chunks, each chunk being
563 a scatterlist. This should be selected by a driver or an API which
564 whishes to split a scatterlist amongst multiple DMA channels.
566 config SG_POOL
567 def_bool n
568 help
569 Provides a helper to allocate chained scatterlists. This should be
570 selected by a driver or an API which whishes to allocate chained
571 scatterlist.
573 #
574 # sg chaining option
575 #
577 config ARCH_HAS_SG_CHAIN
578 def_bool n
580 config ARCH_HAS_PMEM_API
581 bool
583 config ARCH_HAS_UACCESS_FLUSHCACHE
584 bool
586 config ARCH_HAS_UACCESS_MCSAFE
587 bool
589 config STACKDEPOT
590 bool
591 select STACKTRACE
593 config SBITMAP
594 bool
596 config PARMAN
597 tristate "parman" if COMPILE_TEST
599 config PRIME_NUMBERS
600 tristate
602 config STRING_SELFTEST
603 tristate "Test string functions"
605 endmenu
607 config GENERIC_LIB_ASHLDI3
608 bool
610 config GENERIC_LIB_ASHRDI3
611 bool
613 config GENERIC_LIB_LSHRDI3
614 bool
616 config GENERIC_LIB_MULDI3
617 bool
619 config GENERIC_LIB_CMPDI2
620 bool
622 config GENERIC_LIB_UCMPDI2
623 bool