xref: /linux/lib/Kconfig (revision 827634added7f38b7d724cab1dccdb2b004c13c3)
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 GENERIC_IO
50	bool
51	default n
52
53config STMP_DEVICE
54	bool
55
56config PERCPU_RWSEM
57	bool
58
59config ARCH_USE_CMPXCHG_LOCKREF
60	bool
61
62config ARCH_HAS_FAST_MULTIPLIER
63	bool
64
65config CRC_CCITT
66	tristate "CRC-CCITT functions"
67	help
68	  This option is provided for the case where no in-kernel-tree
69	  modules require CRC-CCITT functions, but a module built outside
70	  the kernel tree does. Such modules that use library CRC-CCITT
71	  functions require M here.
72
73config CRC16
74	tristate "CRC16 functions"
75	help
76	  This option is provided for the case where no in-kernel-tree
77	  modules require CRC16 functions, but a module built outside
78	  the kernel tree does. Such modules that use library CRC16
79	  functions require M here.
80
81config CRC_T10DIF
82	tristate "CRC calculation for the T10 Data Integrity Field"
83	select CRYPTO
84	select CRYPTO_CRCT10DIF
85	help
86	  This option is only needed if a module that's not in the
87	  kernel tree needs to calculate CRC checks for use with the
88	  SCSI data integrity subsystem.
89
90config CRC_ITU_T
91	tristate "CRC ITU-T V.41 functions"
92	help
93	  This option is provided for the case where no in-kernel-tree
94	  modules require CRC ITU-T V.41 functions, but a module built outside
95	  the kernel tree does. Such modules that use library CRC ITU-T V.41
96	  functions require M here.
97
98config CRC32
99	tristate "CRC32/CRC32c functions"
100	default y
101	select BITREVERSE
102	help
103	  This option is provided for the case where no in-kernel-tree
104	  modules require CRC32/CRC32c functions, but a module built outside
105	  the kernel tree does. Such modules that use library CRC32/CRC32c
106	  functions require M here.
107
108config CRC32_SELFTEST
109	bool "CRC32 perform self test on init"
110	default n
111	depends on CRC32
112	help
113	  This option enables the CRC32 library functions to perform a
114	  self test on initialization. The self test computes crc32_le
115	  and crc32_be over byte strings with random alignment and length
116	  and computes the total elapsed time and number of bytes processed.
117
118choice
119	prompt "CRC32 implementation"
120	depends on CRC32
121	default CRC32_SLICEBY8
122	help
123	  This option allows a kernel builder to override the default choice
124	  of CRC32 algorithm.  Choose the default ("slice by 8") unless you
125	  know that you need one of the others.
126
127config CRC32_SLICEBY8
128	bool "Slice by 8 bytes"
129	help
130	  Calculate checksum 8 bytes at a time with a clever slicing algorithm.
131	  This is the fastest algorithm, but comes with a 8KiB lookup table.
132	  Most modern processors have enough cache to hold this table without
133	  thrashing the cache.
134
135	  This is the default implementation choice.  Choose this one unless
136	  you have a good reason not to.
137
138config CRC32_SLICEBY4
139	bool "Slice by 4 bytes"
140	help
141	  Calculate checksum 4 bytes at a time with a clever slicing algorithm.
142	  This is a bit slower than slice by 8, but has a smaller 4KiB lookup
143	  table.
144
145	  Only choose this option if you know what you are doing.
146
147config CRC32_SARWATE
148	bool "Sarwate's Algorithm (one byte at a time)"
149	help
150	  Calculate checksum a byte at a time using Sarwate's algorithm.  This
151	  is not particularly fast, but has a small 256 byte lookup table.
152
153	  Only choose this option if you know what you are doing.
154
155config CRC32_BIT
156	bool "Classic Algorithm (one bit at a time)"
157	help
158	  Calculate checksum one bit at a time.  This is VERY slow, but has
159	  no lookup table.  This is provided as a debugging option.
160
161	  Only choose this option if you are debugging crc32.
162
163endchoice
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 AUDIT_GENERIC
192	bool
193	depends on AUDIT && !AUDIT_ARCH
194	default y
195
196config AUDIT_ARCH_COMPAT_GENERIC
197	bool
198	default n
199
200config AUDIT_COMPAT_GENERIC
201	bool
202	depends on AUDIT_GENERIC && AUDIT_ARCH_COMPAT_GENERIC && COMPAT
203	default y
204
205config RANDOM32_SELFTEST
206	bool "PRNG perform self test on init"
207	default n
208	help
209	  This option enables the 32 bit PRNG library functions to perform a
210	  self test on initialization.
211
212#
213# compression support is select'ed if needed
214#
215config ZLIB_INFLATE
216	tristate
217
218config ZLIB_DEFLATE
219	tristate
220
221config LZO_COMPRESS
222	tristate
223
224config LZO_DECOMPRESS
225	tristate
226
227config LZ4_COMPRESS
228	tristate
229
230config LZ4HC_COMPRESS
231	tristate
232
233config LZ4_DECOMPRESS
234	tristate
235
236source "lib/xz/Kconfig"
237
238#
239# These all provide a common interface (hence the apparent duplication with
240# ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.)
241#
242config DECOMPRESS_GZIP
243	select ZLIB_INFLATE
244	tristate
245
246config DECOMPRESS_BZIP2
247	tristate
248
249config DECOMPRESS_LZMA
250	tristate
251
252config DECOMPRESS_XZ
253	select XZ_DEC
254	tristate
255
256config DECOMPRESS_LZO
257	select LZO_DECOMPRESS
258	tristate
259
260config DECOMPRESS_LZ4
261	select LZ4_DECOMPRESS
262	tristate
263
264#
265# Generic allocator support is selected if needed
266#
267config GENERIC_ALLOCATOR
268	bool
269
270#
271# reed solomon support is select'ed if needed
272#
273config REED_SOLOMON
274	tristate
275
276config REED_SOLOMON_ENC8
277	bool
278
279config REED_SOLOMON_DEC8
280	bool
281
282config REED_SOLOMON_ENC16
283	bool
284
285config REED_SOLOMON_DEC16
286	bool
287
288#
289# BCH support is selected if needed
290#
291config BCH
292	tristate
293
294config BCH_CONST_PARAMS
295	bool
296	help
297	  Drivers may select this option to force specific constant
298	  values for parameters 'm' (Galois field order) and 't'
299	  (error correction capability). Those specific values must
300	  be set by declaring default values for symbols BCH_CONST_M
301	  and BCH_CONST_T.
302	  Doing so will enable extra compiler optimizations,
303	  improving encoding and decoding performance up to 2x for
304	  usual (m,t) values (typically such that m*t < 200).
305	  When this option is selected, the BCH library supports
306	  only a single (m,t) configuration. This is mainly useful
307	  for NAND flash board drivers requiring known, fixed BCH
308	  parameters.
309
310config BCH_CONST_M
311	int
312	range 5 15
313	help
314	  Constant value for Galois field order 'm'. If 'k' is the
315	  number of data bits to protect, 'm' should be chosen such
316	  that (k + m*t) <= 2**m - 1.
317	  Drivers should declare a default value for this symbol if
318	  they select option BCH_CONST_PARAMS.
319
320config BCH_CONST_T
321	int
322	help
323	  Constant value for error correction capability in bits 't'.
324	  Drivers should declare a default value for this symbol if
325	  they select option BCH_CONST_PARAMS.
326
327#
328# Textsearch support is select'ed if needed
329#
330config TEXTSEARCH
331	bool
332
333config TEXTSEARCH_KMP
334	tristate
335
336config TEXTSEARCH_BM
337	tristate
338
339config TEXTSEARCH_FSM
340	tristate
341
342config BTREE
343	bool
344
345config INTERVAL_TREE
346	bool
347	help
348	  Simple, embeddable, interval-tree. Can find the start of an
349	  overlapping range in log(n) time and then iterate over all
350	  overlapping nodes. The algorithm is implemented as an
351	  augmented rbtree.
352
353	  See:
354
355		Documentation/rbtree.txt
356
357	  for more information.
358
359config ASSOCIATIVE_ARRAY
360	bool
361	help
362	  Generic associative array.  Can be searched and iterated over whilst
363	  it is being modified.  It is also reasonably quick to search and
364	  modify.  The algorithms are non-recursive, and the trees are highly
365	  capacious.
366
367	  See:
368
369		Documentation/assoc_array.txt
370
371	  for more information.
372
373config HAS_IOMEM
374	bool
375	depends on !NO_IOMEM
376	select GENERIC_IO
377	default y
378
379config HAS_IOPORT_MAP
380	bool
381	depends on HAS_IOMEM && !NO_IOPORT_MAP
382	default y
383
384config HAS_DMA
385	bool
386	depends on !NO_DMA
387	default y
388
389config CHECK_SIGNATURE
390	bool
391
392config CPUMASK_OFFSTACK
393	bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
394	help
395	  Use dynamic allocation for cpumask_var_t, instead of putting
396	  them on the stack.  This is a bit more expensive, but avoids
397	  stack overflow.
398
399config CPU_RMAP
400	bool
401	depends on SMP
402
403config DQL
404	bool
405
406config GLOB
407	bool
408#	This actually supports modular compilation, but the module overhead
409#	is ridiculous for the amount of code involved.	Until an out-of-tree
410#	driver asks for it, we'll just link it directly it into the kernel
411#	when required.  Since we're ignoring out-of-tree users,	there's also
412#	no need bother prompting for a manual decision:
413#	prompt "glob_match() function"
414	help
415	  This option provides a glob_match function for performing
416	  simple text pattern matching.  It originated in the ATA code
417	  to blacklist particular drive models, but other device drivers
418	  may need similar functionality.
419
420	  All drivers in the Linux kernel tree that require this function
421	  should automatically select this option.  Say N unless you
422	  are compiling an out-of tree driver which tells you that it
423	  depends on this.
424
425config GLOB_SELFTEST
426	bool "glob self-test on init"
427	default n
428	depends on GLOB
429	help
430	  This option enables a simple self-test of the glob_match
431	  function on startup.	It is primarily useful for people
432	  working on the code to ensure they haven't introduced any
433	  regressions.
434
435	  It only adds a little bit of code and slows kernel boot (or
436	  module load) by a small amount, so you're welcome to play with
437	  it, but you probably don't need it.
438
439#
440# Netlink attribute parsing support is select'ed if needed
441#
442config NLATTR
443	bool
444
445#
446# Generic 64-bit atomic support is selected if needed
447#
448config GENERIC_ATOMIC64
449       bool
450
451config ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
452	def_bool y if GENERIC_ATOMIC64
453
454config LRU_CACHE
455	tristate
456
457config AVERAGE
458	bool "Averaging functions"
459	help
460	  This option is provided for the case where no in-kernel-tree
461	  modules require averaging functions, but a module built outside
462	  the kernel tree does. Such modules that use library averaging
463	  functions require Y here.
464
465	  If unsure, say N.
466
467config CLZ_TAB
468	bool
469
470config CORDIC
471	tristate "CORDIC algorithm"
472	help
473	  This option provides an implementation of the CORDIC algorithm;
474	  calculations are in fixed point. Module will be called cordic.
475
476config DDR
477	bool "JEDEC DDR data"
478	help
479	  Data from JEDEC specs for DDR SDRAM memories,
480	  particularly the AC timing parameters and addressing
481	  information. This data is useful for drivers handling
482	  DDR SDRAM controllers.
483
484config MPILIB
485	tristate
486	select CLZ_TAB
487	help
488	  Multiprecision maths library from GnuPG.
489	  It is used to implement RSA digital signature verification,
490	  which is used by IMA/EVM digital signature extension.
491
492config SIGNATURE
493	tristate
494	depends on KEYS
495	select CRYPTO
496	select CRYPTO_SHA1
497	select MPILIB
498	help
499	  Digital signature verification. Currently only RSA is supported.
500	  Implementation is done using GnuPG MPI library
501
502#
503# libfdt files, only selected if needed.
504#
505config LIBFDT
506	bool
507
508config OID_REGISTRY
509	tristate
510	help
511	  Enable fast lookup object identifier registry.
512
513config UCS2_STRING
514        tristate
515
516source "lib/fonts/Kconfig"
517
518#
519# sg chaining option
520#
521
522config ARCH_HAS_SG_CHAIN
523	def_bool n
524
525endmenu
526