xref: /linux/lib/Kconfig (revision fd639726bf15fca8ee1a00dce8e0096d0ad9bd18)
1#
2# Library configuration
3#
4
5config BINARY_PRINTF
6	def_bool n
7
8menu "Library routines"
9
10config RAID6_PQ
11	tristate
12
13config BITREVERSE
14	tristate
15
16config 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.
23
24config RATIONAL
25	bool
26
27config GENERIC_STRNCPY_FROM_USER
28	bool
29
30config GENERIC_STRNLEN_USER
31	bool
32
33config GENERIC_NET_UTILS
34	bool
35
36config GENERIC_FIND_FIRST_BIT
37	bool
38
39config NO_GENERIC_PCI_IOPORT_MAP
40	bool
41
42config GENERIC_PCI_IOMAP
43	bool
44
45config GENERIC_IOMAP
46	bool
47	select GENERIC_PCI_IOMAP
48
49config STMP_DEVICE
50	bool
51
52config ARCH_USE_CMPXCHG_LOCKREF
53	bool
54
55config ARCH_HAS_FAST_MULTIPLIER
56	bool
57
58config CRC_CCITT
59	tristate "CRC-CCITT functions"
60	help
61	  This option is provided for the case where no in-kernel-tree
62	  modules require CRC-CCITT functions, but a module built outside
63	  the kernel tree does. Such modules that use library CRC-CCITT
64	  functions require M here.
65
66config CRC16
67	tristate "CRC16 functions"
68	help
69	  This option is provided for the case where no in-kernel-tree
70	  modules require CRC16 functions, but a module built outside
71	  the kernel tree does. Such modules that use library CRC16
72	  functions require M here.
73
74config CRC_T10DIF
75	tristate "CRC calculation for the T10 Data Integrity Field"
76	select CRYPTO
77	select CRYPTO_CRCT10DIF
78	help
79	  This option is only needed if a module that's not in the
80	  kernel tree needs to calculate CRC checks for use with the
81	  SCSI data integrity subsystem.
82
83config CRC_ITU_T
84	tristate "CRC ITU-T V.41 functions"
85	help
86	  This option is provided for the case where no in-kernel-tree
87	  modules require CRC ITU-T V.41 functions, but a module built outside
88	  the kernel tree does. Such modules that use library CRC ITU-T V.41
89	  functions require M here.
90
91config CRC32
92	tristate "CRC32/CRC32c functions"
93	default y
94	select BITREVERSE
95	help
96	  This option is provided for the case where no in-kernel-tree
97	  modules require CRC32/CRC32c functions, but a module built outside
98	  the kernel tree does. Such modules that use library CRC32/CRC32c
99	  functions require M here.
100
101config CRC32_SELFTEST
102	tristate "CRC32 perform self test on init"
103	depends on CRC32
104	help
105	  This option enables the CRC32 library functions to perform a
106	  self test on initialization. The self test computes crc32_le
107	  and crc32_be over byte strings with random alignment and length
108	  and computes the total elapsed time and number of bytes processed.
109
110choice
111	prompt "CRC32 implementation"
112	depends on CRC32
113	default CRC32_SLICEBY8
114	help
115	  This option allows a kernel builder to override the default choice
116	  of CRC32 algorithm.  Choose the default ("slice by 8") unless you
117	  know that you need one of the others.
118
119config CRC32_SLICEBY8
120	bool "Slice by 8 bytes"
121	help
122	  Calculate checksum 8 bytes at a time with a clever slicing algorithm.
123	  This is the fastest algorithm, but comes with a 8KiB lookup table.
124	  Most modern processors have enough cache to hold this table without
125	  thrashing the cache.
126
127	  This is the default implementation choice.  Choose this one unless
128	  you have a good reason not to.
129
130config CRC32_SLICEBY4
131	bool "Slice by 4 bytes"
132	help
133	  Calculate checksum 4 bytes at a time with a clever slicing algorithm.
134	  This is a bit slower than slice by 8, but has a smaller 4KiB lookup
135	  table.
136
137	  Only choose this option if you know what you are doing.
138
139config CRC32_SARWATE
140	bool "Sarwate's Algorithm (one byte at a time)"
141	help
142	  Calculate checksum a byte at a time using Sarwate's algorithm.  This
143	  is not particularly fast, but has a small 256 byte lookup table.
144
145	  Only choose this option if you know what you are doing.
146
147config CRC32_BIT
148	bool "Classic Algorithm (one bit at a time)"
149	help
150	  Calculate checksum one bit at a time.  This is VERY slow, but has
151	  no lookup table.  This is provided as a debugging option.
152
153	  Only choose this option if you are debugging crc32.
154
155endchoice
156
157config CRC4
158	tristate "CRC4 functions"
159	help
160	  This option is provided for the case where no in-kernel-tree
161	  modules require CRC4 functions, but a module built outside
162	  the kernel tree does. Such modules that use library CRC4
163	  functions require M here.
164
165config CRC7
166	tristate "CRC7 functions"
167	help
168	  This option is provided for the case where no in-kernel-tree
169	  modules require CRC7 functions, but a module built outside
170	  the kernel tree does. Such modules that use library CRC7
171	  functions require M here.
172
173config LIBCRC32C
174	tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check"
175	select CRYPTO
176	select CRYPTO_CRC32C
177	help
178	  This option is provided for the case where no in-kernel-tree
179	  modules require CRC32c functions, but a module built outside the
180	  kernel tree does. Such modules that use library CRC32c functions
181	  require M here.  See Castagnoli93.
182	  Module will be libcrc32c.
183
184config CRC8
185	tristate "CRC8 function"
186	help
187	  This option provides CRC8 function. Drivers may select this
188	  when they need to do cyclic redundancy check according CRC8
189	  algorithm. Module will be called crc8.
190
191config XXHASH
192	tristate
193
194config AUDIT_GENERIC
195	bool
196	depends on AUDIT && !AUDIT_ARCH
197	default y
198
199config AUDIT_ARCH_COMPAT_GENERIC
200	bool
201	default n
202
203config AUDIT_COMPAT_GENERIC
204	bool
205	depends on AUDIT_GENERIC && AUDIT_ARCH_COMPAT_GENERIC && COMPAT
206	default y
207
208config RANDOM32_SELFTEST
209	bool "PRNG perform self test on init"
210	default n
211	help
212	  This option enables the 32 bit PRNG library functions to perform a
213	  self test on initialization.
214
215#
216# compression support is select'ed if needed
217#
218config 842_COMPRESS
219	select CRC32
220	tristate
221
222config 842_DECOMPRESS
223	select CRC32
224	tristate
225
226config ZLIB_INFLATE
227	tristate
228
229config ZLIB_DEFLATE
230	tristate
231	select BITREVERSE
232
233config LZO_COMPRESS
234	tristate
235
236config LZO_DECOMPRESS
237	tristate
238
239config LZ4_COMPRESS
240	tristate
241
242config LZ4HC_COMPRESS
243	tristate
244
245config LZ4_DECOMPRESS
246	tristate
247
248config ZSTD_COMPRESS
249	select XXHASH
250	tristate
251
252config ZSTD_DECOMPRESS
253	select XXHASH
254	tristate
255
256source "lib/xz/Kconfig"
257
258#
259# These all provide a common interface (hence the apparent duplication with
260# ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.)
261#
262config DECOMPRESS_GZIP
263	select ZLIB_INFLATE
264	tristate
265
266config DECOMPRESS_BZIP2
267	tristate
268
269config DECOMPRESS_LZMA
270	tristate
271
272config DECOMPRESS_XZ
273	select XZ_DEC
274	tristate
275
276config DECOMPRESS_LZO
277	select LZO_DECOMPRESS
278	tristate
279
280config DECOMPRESS_LZ4
281	select LZ4_DECOMPRESS
282	tristate
283
284#
285# Generic allocator support is selected if needed
286#
287config GENERIC_ALLOCATOR
288	bool
289
290#
291# reed solomon support is select'ed if needed
292#
293config REED_SOLOMON
294	tristate
295
296config REED_SOLOMON_ENC8
297	bool
298
299config REED_SOLOMON_DEC8
300	bool
301
302config REED_SOLOMON_ENC16
303	bool
304
305config REED_SOLOMON_DEC16
306	bool
307
308#
309# BCH support is selected if needed
310#
311config BCH
312	tristate
313
314config BCH_CONST_PARAMS
315	bool
316	help
317	  Drivers may select this option to force specific constant
318	  values for parameters 'm' (Galois field order) and 't'
319	  (error correction capability). Those specific values must
320	  be set by declaring default values for symbols BCH_CONST_M
321	  and BCH_CONST_T.
322	  Doing so will enable extra compiler optimizations,
323	  improving encoding and decoding performance up to 2x for
324	  usual (m,t) values (typically such that m*t < 200).
325	  When this option is selected, the BCH library supports
326	  only a single (m,t) configuration. This is mainly useful
327	  for NAND flash board drivers requiring known, fixed BCH
328	  parameters.
329
330config BCH_CONST_M
331	int
332	range 5 15
333	help
334	  Constant value for Galois field order 'm'. If 'k' is the
335	  number of data bits to protect, 'm' should be chosen such
336	  that (k + m*t) <= 2**m - 1.
337	  Drivers should declare a default value for this symbol if
338	  they select option BCH_CONST_PARAMS.
339
340config BCH_CONST_T
341	int
342	help
343	  Constant value for error correction capability in bits 't'.
344	  Drivers should declare a default value for this symbol if
345	  they select option BCH_CONST_PARAMS.
346
347#
348# Textsearch support is select'ed if needed
349#
350config TEXTSEARCH
351	bool
352
353config TEXTSEARCH_KMP
354	tristate
355
356config TEXTSEARCH_BM
357	tristate
358
359config TEXTSEARCH_FSM
360	tristate
361
362config BTREE
363	bool
364
365config INTERVAL_TREE
366	bool
367	help
368	  Simple, embeddable, interval-tree. Can find the start of an
369	  overlapping range in log(n) time and then iterate over all
370	  overlapping nodes. The algorithm is implemented as an
371	  augmented rbtree.
372
373	  See:
374
375		Documentation/rbtree.txt
376
377	  for more information.
378
379config RADIX_TREE_MULTIORDER
380	bool
381
382config ASSOCIATIVE_ARRAY
383	bool
384	help
385	  Generic associative array.  Can be searched and iterated over whilst
386	  it is being modified.  It is also reasonably quick to search and
387	  modify.  The algorithms are non-recursive, and the trees are highly
388	  capacious.
389
390	  See:
391
392		Documentation/assoc_array.txt
393
394	  for more information.
395
396config HAS_IOMEM
397	bool
398	depends on !NO_IOMEM
399	select GENERIC_IO
400	default y
401
402config HAS_IOPORT_MAP
403	bool
404	depends on HAS_IOMEM && !NO_IOPORT_MAP
405	default y
406
407config HAS_DMA
408	bool
409	depends on !NO_DMA
410	default y
411
412config DMA_NOOP_OPS
413	bool
414	depends on HAS_DMA && (!64BIT || ARCH_DMA_ADDR_T_64BIT)
415	default n
416
417config DMA_VIRT_OPS
418	bool
419	depends on HAS_DMA && (!64BIT || ARCH_DMA_ADDR_T_64BIT)
420	default n
421
422config CHECK_SIGNATURE
423	bool
424
425config CPUMASK_OFFSTACK
426	bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
427	help
428	  Use dynamic allocation for cpumask_var_t, instead of putting
429	  them on the stack.  This is a bit more expensive, but avoids
430	  stack overflow.
431
432config CPU_RMAP
433	bool
434	depends on SMP
435
436config DQL
437	bool
438
439config GLOB
440	bool
441#	This actually supports modular compilation, but the module overhead
442#	is ridiculous for the amount of code involved.	Until an out-of-tree
443#	driver asks for it, we'll just link it directly it into the kernel
444#	when required.  Since we're ignoring out-of-tree users,	there's also
445#	no need bother prompting for a manual decision:
446#	prompt "glob_match() function"
447	help
448	  This option provides a glob_match function for performing
449	  simple text pattern matching.  It originated in the ATA code
450	  to blacklist particular drive models, but other device drivers
451	  may need similar functionality.
452
453	  All drivers in the Linux kernel tree that require this function
454	  should automatically select this option.  Say N unless you
455	  are compiling an out-of tree driver which tells you that it
456	  depends on this.
457
458config GLOB_SELFTEST
459	tristate "glob self-test on init"
460	depends on GLOB
461	help
462	  This option enables a simple self-test of the glob_match
463	  function on startup.	It is primarily useful for people
464	  working on the code to ensure they haven't introduced any
465	  regressions.
466
467	  It only adds a little bit of code and slows kernel boot (or
468	  module load) by a small amount, so you're welcome to play with
469	  it, but you probably don't need it.
470
471#
472# Netlink attribute parsing support is select'ed if needed
473#
474config NLATTR
475	bool
476
477#
478# Generic 64-bit atomic support is selected if needed
479#
480config GENERIC_ATOMIC64
481       bool
482
483config LRU_CACHE
484	tristate
485
486config CLZ_TAB
487	bool
488
489config CORDIC
490	tristate "CORDIC algorithm"
491	help
492	  This option provides an implementation of the CORDIC algorithm;
493	  calculations are in fixed point. Module will be called cordic.
494
495config DDR
496	bool "JEDEC DDR data"
497	help
498	  Data from JEDEC specs for DDR SDRAM memories,
499	  particularly the AC timing parameters and addressing
500	  information. This data is useful for drivers handling
501	  DDR SDRAM controllers.
502
503config IRQ_POLL
504	bool "IRQ polling library"
505	help
506	  Helper library to poll interrupt mitigation using polling.
507
508config MPILIB
509	tristate
510	select CLZ_TAB
511	help
512	  Multiprecision maths library from GnuPG.
513	  It is used to implement RSA digital signature verification,
514	  which is used by IMA/EVM digital signature extension.
515
516config SIGNATURE
517	tristate
518	depends on KEYS
519	select CRYPTO
520	select CRYPTO_SHA1
521	select MPILIB
522	help
523	  Digital signature verification. Currently only RSA is supported.
524	  Implementation is done using GnuPG MPI library
525
526#
527# libfdt files, only selected if needed.
528#
529config LIBFDT
530	bool
531
532config OID_REGISTRY
533	tristate
534	help
535	  Enable fast lookup object identifier registry.
536
537config UCS2_STRING
538        tristate
539
540source "lib/fonts/Kconfig"
541
542config SG_SPLIT
543	def_bool n
544	help
545	 Provides a helper to split scatterlists into chunks, each chunk being
546	 a scatterlist. This should be selected by a driver or an API which
547	 whishes to split a scatterlist amongst multiple DMA channels.
548
549config SG_POOL
550	def_bool n
551	help
552	 Provides a helper to allocate chained scatterlists. This should be
553	 selected by a driver or an API which whishes to allocate chained
554	 scatterlist.
555
556#
557# sg chaining option
558#
559
560config ARCH_HAS_SG_CHAIN
561	def_bool n
562
563config ARCH_HAS_PMEM_API
564	bool
565
566config ARCH_HAS_UACCESS_FLUSHCACHE
567	bool
568
569config STACKDEPOT
570	bool
571	select STACKTRACE
572
573config SBITMAP
574	bool
575
576config PARMAN
577	tristate "parman" if COMPILE_TEST
578
579config PRIME_NUMBERS
580	tristate
581
582config STRING_SELFTEST
583	tristate "Test string functions"
584
585endmenu
586
587config GENERIC_ASHLDI3
588	bool
589
590config GENERIC_ASHRDI3
591	bool
592
593config GENERIC_LSHRDI3
594	bool
595
596config GENERIC_MULDI3
597	bool
598
599config GENERIC_CMPDI2
600	bool
601
602config GENERIC_UCMPDI2
603	bool
604