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1# SPDX-License-Identifier: GPL-2.0-only
2#
3# Library configuration
4#
5
6config BINARY_PRINTF
7 def_bool n
8
9menu "Library routines"
10
11config RAID6_PQ
12 tristate
13
14config RAID6_PQ_BENCHMARK
15 bool "Automatically choose fastest RAID6 PQ functions"
16 depends on RAID6_PQ
17 default y
18 help
19 Benchmark all available RAID6 PQ functions on init and choose the
20 fastest one.
21
22config LINEAR_RANGES
23 tristate
24
25config PACKING
26 bool "Generic bitfield packing and unpacking"
27 select BITREVERSE
28 default n
29 help
30 This option provides the packing() helper function, which permits
31 converting bitfields between a CPU-usable representation and a
32 memory representation that can have any combination of these quirks:
33 - Is little endian (bytes are reversed within a 32-bit group)
34 - The least-significant 32-bit word comes first (within a 64-bit
35 group)
36 - The most significant bit of a byte is at its right (bit 0 of a
37 register description is numerically 2^7).
38 Drivers may use these helpers to match the bit indices as described
39 in the data sheets of the peripherals they are in control of.
40
41 When in doubt, say N.
42
43config PACKING_KUNIT_TEST
44 tristate "KUnit tests for packing library" if !KUNIT_ALL_TESTS
45 depends on PACKING && KUNIT
46 default KUNIT_ALL_TESTS
47 help
48 This builds KUnit tests for the packing library.
49
50 For more information on KUnit and unit tests in general,
51 please refer to the KUnit documentation in Documentation/dev-tools/kunit/.
52
53 When in doubt, say N.
54
55config BITREVERSE
56 tristate
57
58config HAVE_ARCH_BITREVERSE
59 bool
60 default n
61 help
62 This option enables the use of hardware bit-reversal instructions on
63 architectures which support such operations.
64
65config ARCH_HAS_STRNCPY_FROM_USER
66 bool
67
68config ARCH_HAS_STRNLEN_USER
69 bool
70
71config GENERIC_STRNCPY_FROM_USER
72 def_bool !ARCH_HAS_STRNCPY_FROM_USER
73
74config GENERIC_STRNLEN_USER
75 def_bool !ARCH_HAS_STRNLEN_USER
76
77config GENERIC_NET_UTILS
78 bool
79
80source "lib/math/Kconfig"
81
82config NO_GENERIC_PCI_IOPORT_MAP
83 bool
84
85config GENERIC_IOMAP
86 bool
87 select GENERIC_PCI_IOMAP
88
89config STMP_DEVICE
90 bool
91
92config ARCH_USE_CMPXCHG_LOCKREF
93 bool
94
95config ARCH_HAS_FAST_MULTIPLIER
96 bool
97
98config ARCH_USE_SYM_ANNOTATIONS
99 bool
100
101config INDIRECT_PIO
102 bool "Access I/O in non-MMIO mode"
103 depends on ARM64
104 depends on HAS_IOPORT
105 help
106 On some platforms where no separate I/O space exists, there are I/O
107 hosts which can not be accessed in MMIO mode. Using the logical PIO
108 mechanism, the host-local I/O resource can be mapped into system
109 logic PIO space shared with MMIO hosts, such as PCI/PCIe, then the
110 system can access the I/O devices with the mapped-logic PIO through
111 I/O accessors.
112
113 This way has relatively little I/O performance cost. Please make
114 sure your devices really need this configure item enabled.
115
116 When in doubt, say N.
117
118config INDIRECT_IOMEM
119 bool
120 help
121 This is selected by other options/architectures to provide the
122 emulated iomem accessors.
123
124config INDIRECT_IOMEM_FALLBACK
125 bool
126 depends on INDIRECT_IOMEM
127 help
128 If INDIRECT_IOMEM is selected, this enables falling back to plain
129 mmio accesses when the IO memory address is not a registered
130 emulated region.
131
132config TRACE_MMIO_ACCESS
133 bool "Register read/write tracing"
134 depends on TRACING && ARCH_HAVE_TRACE_MMIO_ACCESS
135 help
136 Create tracepoints for MMIO read/write operations. These trace events
137 can be used for logging all MMIO read/write operations.
138
139source "lib/crypto/Kconfig"
140
141config CRC_CCITT
142 tristate "CRC-CCITT functions"
143 help
144 This option is provided for the case where no in-kernel-tree
145 modules require CRC-CCITT functions, but a module built outside
146 the kernel tree does. Such modules that use library CRC-CCITT
147 functions require M here.
148
149config CRC16
150 tristate "CRC16 functions"
151 help
152 This option is provided for the case where no in-kernel-tree
153 modules require CRC16 functions, but a module built outside
154 the kernel tree does. Such modules that use library CRC16
155 functions require M here.
156
157config CRC_T10DIF
158 tristate "CRC calculation for the T10 Data Integrity Field"
159 select CRYPTO
160 select CRYPTO_CRCT10DIF
161 help
162 This option is only needed if a module that's not in the
163 kernel tree needs to calculate CRC checks for use with the
164 SCSI data integrity subsystem.
165
166config CRC64_ROCKSOFT
167 tristate "CRC calculation for the Rocksoft model CRC64"
168 select CRC64
169 select CRYPTO
170 select CRYPTO_CRC64_ROCKSOFT
171 help
172 This option provides a CRC64 API to a registered crypto driver.
173 This is used with the block layer's data integrity subsystem.
174
175config CRC_ITU_T
176 tristate "CRC ITU-T V.41 functions"
177 help
178 This option is provided for the case where no in-kernel-tree
179 modules require CRC ITU-T V.41 functions, but a module built outside
180 the kernel tree does. Such modules that use library CRC ITU-T V.41
181 functions require M here.
182
183config CRC32
184 tristate "CRC32/CRC32c functions"
185 default y
186 select BITREVERSE
187 help
188 This option is provided for the case where no in-kernel-tree
189 modules require CRC32/CRC32c functions, but a module built outside
190 the kernel tree does. Such modules that use library CRC32/CRC32c
191 functions require M here.
192
193config CRC32_SELFTEST
194 tristate "CRC32 perform self test on init"
195 depends on CRC32
196 help
197 This option enables the CRC32 library functions to perform a
198 self test on initialization. The self test computes crc32_le
199 and crc32_be over byte strings with random alignment and length
200 and computes the total elapsed time and number of bytes processed.
201
202choice
203 prompt "CRC32 implementation"
204 depends on CRC32
205 default CRC32_SLICEBY8
206 help
207 This option allows a kernel builder to override the default choice
208 of CRC32 algorithm. Choose the default ("slice by 8") unless you
209 know that you need one of the others.
210
211config CRC32_SLICEBY8
212 bool "Slice by 8 bytes"
213 help
214 Calculate checksum 8 bytes at a time with a clever slicing algorithm.
215 This is the fastest algorithm, but comes with a 8KiB lookup table.
216 Most modern processors have enough cache to hold this table without
217 thrashing the cache.
218
219 This is the default implementation choice. Choose this one unless
220 you have a good reason not to.
221
222config CRC32_SLICEBY4
223 bool "Slice by 4 bytes"
224 help
225 Calculate checksum 4 bytes at a time with a clever slicing algorithm.
226 This is a bit slower than slice by 8, but has a smaller 4KiB lookup
227 table.
228
229 Only choose this option if you know what you are doing.
230
231config CRC32_SARWATE
232 bool "Sarwate's Algorithm (one byte at a time)"
233 help
234 Calculate checksum a byte at a time using Sarwate's algorithm. This
235 is not particularly fast, but has a small 256 byte lookup table.
236
237 Only choose this option if you know what you are doing.
238
239config CRC32_BIT
240 bool "Classic Algorithm (one bit at a time)"
241 help
242 Calculate checksum one bit at a time. This is VERY slow, but has
243 no lookup table. This is provided as a debugging option.
244
245 Only choose this option if you are debugging crc32.
246
247endchoice
248
249config CRC64
250 tristate "CRC64 functions"
251 help
252 This option is provided for the case where no in-kernel-tree
253 modules require CRC64 functions, but a module built outside
254 the kernel tree does. Such modules that use library CRC64
255 functions require M here.
256
257config CRC4
258 tristate "CRC4 functions"
259 help
260 This option is provided for the case where no in-kernel-tree
261 modules require CRC4 functions, but a module built outside
262 the kernel tree does. Such modules that use library CRC4
263 functions require M here.
264
265config CRC7
266 tristate "CRC7 functions"
267 help
268 This option is provided for the case where no in-kernel-tree
269 modules require CRC7 functions, but a module built outside
270 the kernel tree does. Such modules that use library CRC7
271 functions require M here.
272
273config LIBCRC32C
274 tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check"
275 select CRYPTO
276 select CRYPTO_CRC32C
277 help
278 This option is provided for the case where no in-kernel-tree
279 modules require CRC32c functions, but a module built outside the
280 kernel tree does. Such modules that use library CRC32c functions
281 require M here. See Castagnoli93.
282 Module will be libcrc32c.
283
284config CRC8
285 tristate "CRC8 function"
286 help
287 This option provides CRC8 function. Drivers may select this
288 when they need to do cyclic redundancy check according CRC8
289 algorithm. Module will be called crc8.
290
291config XXHASH
292 tristate
293
294config AUDIT_GENERIC
295 bool
296 depends on AUDIT && !AUDIT_ARCH
297 default y
298
299config AUDIT_ARCH_COMPAT_GENERIC
300 bool
301 default n
302
303config AUDIT_COMPAT_GENERIC
304 bool
305 depends on AUDIT_GENERIC && AUDIT_ARCH_COMPAT_GENERIC && COMPAT
306 default y
307
308config RANDOM32_SELFTEST
309 bool "PRNG perform self test on init"
310 help
311 This option enables the 32 bit PRNG library functions to perform a
312 self test on initialization.
313
314#
315# compression support is select'ed if needed
316#
317config 842_COMPRESS
318 select CRC32
319 tristate
320
321config 842_DECOMPRESS
322 select CRC32
323 tristate
324
325config ZLIB_INFLATE
326 tristate
327
328config ZLIB_DEFLATE
329 tristate
330 select BITREVERSE
331
332config ZLIB_DFLTCC
333 def_bool y
334 depends on S390
335 prompt "Enable s390x DEFLATE CONVERSION CALL support for kernel zlib"
336 help
337 Enable s390x hardware support for zlib in the kernel.
338
339config LZO_COMPRESS
340 tristate
341
342config LZO_DECOMPRESS
343 tristate
344
345config LZ4_COMPRESS
346 tristate
347
348config LZ4HC_COMPRESS
349 tristate
350
351config LZ4_DECOMPRESS
352 tristate
353
354config ZSTD_COMMON
355 select XXHASH
356 tristate
357
358config ZSTD_COMPRESS
359 select ZSTD_COMMON
360 tristate
361
362config ZSTD_DECOMPRESS
363 select ZSTD_COMMON
364 tristate
365
366source "lib/xz/Kconfig"
367
368#
369# These all provide a common interface (hence the apparent duplication with
370# ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.)
371#
372config DECOMPRESS_GZIP
373 select ZLIB_INFLATE
374 tristate
375
376config DECOMPRESS_BZIP2
377 tristate
378
379config DECOMPRESS_LZMA
380 tristate
381
382config DECOMPRESS_XZ
383 select XZ_DEC
384 tristate
385
386config DECOMPRESS_LZO
387 select LZO_DECOMPRESS
388 tristate
389
390config DECOMPRESS_LZ4
391 select LZ4_DECOMPRESS
392 tristate
393
394config DECOMPRESS_ZSTD
395 select ZSTD_DECOMPRESS
396 tristate
397
398#
399# Generic allocator support is selected if needed
400#
401config GENERIC_ALLOCATOR
402 bool
403
404#
405# reed solomon support is select'ed if needed
406#
407config REED_SOLOMON
408 tristate
409
410config REED_SOLOMON_ENC8
411 bool
412
413config REED_SOLOMON_DEC8
414 bool
415
416config REED_SOLOMON_ENC16
417 bool
418
419config REED_SOLOMON_DEC16
420 bool
421
422#
423# BCH support is selected if needed
424#
425config BCH
426 tristate
427 select BITREVERSE
428
429config BCH_CONST_PARAMS
430 bool
431 help
432 Drivers may select this option to force specific constant
433 values for parameters 'm' (Galois field order) and 't'
434 (error correction capability). Those specific values must
435 be set by declaring default values for symbols BCH_CONST_M
436 and BCH_CONST_T.
437 Doing so will enable extra compiler optimizations,
438 improving encoding and decoding performance up to 2x for
439 usual (m,t) values (typically such that m*t < 200).
440 When this option is selected, the BCH library supports
441 only a single (m,t) configuration. This is mainly useful
442 for NAND flash board drivers requiring known, fixed BCH
443 parameters.
444
445config BCH_CONST_M
446 int
447 range 5 15
448 help
449 Constant value for Galois field order 'm'. If 'k' is the
450 number of data bits to protect, 'm' should be chosen such
451 that (k + m*t) <= 2**m - 1.
452 Drivers should declare a default value for this symbol if
453 they select option BCH_CONST_PARAMS.
454
455config BCH_CONST_T
456 int
457 help
458 Constant value for error correction capability in bits 't'.
459 Drivers should declare a default value for this symbol if
460 they select option BCH_CONST_PARAMS.
461
462#
463# Textsearch support is select'ed if needed
464#
465config TEXTSEARCH
466 bool
467
468config TEXTSEARCH_KMP
469 tristate
470
471config TEXTSEARCH_BM
472 tristate
473
474config TEXTSEARCH_FSM
475 tristate
476
477config BTREE
478 bool
479
480config INTERVAL_TREE
481 bool
482 help
483 Simple, embeddable, interval-tree. Can find the start of an
484 overlapping range in log(n) time and then iterate over all
485 overlapping nodes. The algorithm is implemented as an
486 augmented rbtree.
487
488 See:
489
490 Documentation/core-api/rbtree.rst
491
492 for more information.
493
494config INTERVAL_TREE_SPAN_ITER
495 bool
496 depends on INTERVAL_TREE
497
498config XARRAY_MULTI
499 bool
500 help
501 Support entries which occupy multiple consecutive indices in the
502 XArray.
503
504config ASSOCIATIVE_ARRAY
505 bool
506 help
507 Generic associative array. Can be searched and iterated over whilst
508 it is being modified. It is also reasonably quick to search and
509 modify. The algorithms are non-recursive, and the trees are highly
510 capacious.
511
512 See:
513
514 Documentation/core-api/assoc_array.rst
515
516 for more information.
517
518config CLOSURES
519 bool
520
521config HAS_IOMEM
522 bool
523 depends on !NO_IOMEM
524 default y
525
526config HAS_IOPORT
527 bool
528
529config HAS_IOPORT_MAP
530 bool
531 depends on HAS_IOMEM && !NO_IOPORT_MAP
532 default y
533
534source "kernel/dma/Kconfig"
535
536config SGL_ALLOC
537 bool
538 default n
539
540config IOMMU_HELPER
541 bool
542
543config CHECK_SIGNATURE
544 bool
545
546config CPUMASK_OFFSTACK
547 bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
548 help
549 Use dynamic allocation for cpumask_var_t, instead of putting
550 them on the stack. This is a bit more expensive, but avoids
551 stack overflow.
552
553config FORCE_NR_CPUS
554 def_bool !SMP
555
556config CPU_RMAP
557 bool
558 depends on SMP
559
560config DQL
561 bool
562
563config GLOB
564 bool
565# This actually supports modular compilation, but the module overhead
566# is ridiculous for the amount of code involved. Until an out-of-tree
567# driver asks for it, we'll just link it directly it into the kernel
568# when required. Since we're ignoring out-of-tree users, there's also
569# no need bother prompting for a manual decision:
570# prompt "glob_match() function"
571 help
572 This option provides a glob_match function for performing
573 simple text pattern matching. It originated in the ATA code
574 to blacklist particular drive models, but other device drivers
575 may need similar functionality.
576
577 All drivers in the Linux kernel tree that require this function
578 should automatically select this option. Say N unless you
579 are compiling an out-of tree driver which tells you that it
580 depends on this.
581
582config GLOB_SELFTEST
583 tristate "glob self-test on init"
584 depends on GLOB
585 help
586 This option enables a simple self-test of the glob_match
587 function on startup. It is primarily useful for people
588 working on the code to ensure they haven't introduced any
589 regressions.
590
591 It only adds a little bit of code and slows kernel boot (or
592 module load) by a small amount, so you're welcome to play with
593 it, but you probably don't need it.
594
595#
596# Netlink attribute parsing support is select'ed if needed
597#
598config NLATTR
599 bool
600
601#
602# Generic 64-bit atomic support is selected if needed
603#
604config GENERIC_ATOMIC64
605 bool
606
607config LRU_CACHE
608 tristate
609
610config CLZ_TAB
611 bool
612
613config IRQ_POLL
614 bool "IRQ polling library"
615 help
616 Helper library to poll interrupt mitigation using polling.
617
618config MPILIB
619 tristate
620 select CLZ_TAB
621 help
622 Multiprecision maths library from GnuPG.
623 It is used to implement RSA digital signature verification,
624 which is used by IMA/EVM digital signature extension.
625
626config SIGNATURE
627 tristate
628 depends on KEYS
629 select CRYPTO
630 select CRYPTO_SHA1
631 select MPILIB
632 help
633 Digital signature verification. Currently only RSA is supported.
634 Implementation is done using GnuPG MPI library
635
636config DIMLIB
637 tristate
638 depends on NET
639 help
640 Dynamic Interrupt Moderation library.
641 Implements an algorithm for dynamically changing CQ moderation values
642 according to run time performance.
643
644#
645# libfdt files, only selected if needed.
646#
647config LIBFDT
648 bool
649
650config OID_REGISTRY
651 tristate
652 help
653 Enable fast lookup object identifier registry.
654
655config UCS2_STRING
656 tristate
657
658#
659# generic vdso
660#
661source "lib/vdso/Kconfig"
662
663source "lib/fonts/Kconfig"
664
665config SG_SPLIT
666 def_bool n
667 help
668 Provides a helper to split scatterlists into chunks, each chunk being
669 a scatterlist. This should be selected by a driver or an API which
670 whishes to split a scatterlist amongst multiple DMA channels.
671
672config SG_POOL
673 def_bool n
674 help
675 Provides a helper to allocate chained scatterlists. This should be
676 selected by a driver or an API which whishes to allocate chained
677 scatterlist.
678
679#
680# sg chaining option
681#
682
683config ARCH_NO_SG_CHAIN
684 def_bool n
685
686config ARCH_HAS_PMEM_API
687 bool
688
689config MEMREGION
690 bool
691
692config ARCH_HAS_CPU_CACHE_INVALIDATE_MEMREGION
693 bool
694
695config ARCH_HAS_MEMREMAP_COMPAT_ALIGN
696 bool
697
698# use memcpy to implement user copies for nommu architectures
699config UACCESS_MEMCPY
700 bool
701
702config ARCH_HAS_UACCESS_FLUSHCACHE
703 bool
704
705# arch has a concept of a recoverable synchronous exception due to a
706# memory-read error like x86 machine-check or ARM data-abort, and
707# implements copy_mc_to_{user,kernel} to abort and report
708# 'bytes-transferred' if that exception fires when accessing the source
709# buffer.
710config ARCH_HAS_COPY_MC
711 bool
712
713# Temporary. Goes away when all archs are cleaned up
714config ARCH_STACKWALK
715 bool
716
717config STACKDEPOT
718 bool
719 select STACKTRACE
720 help
721 Stack depot: stack trace storage that avoids duplication
722
723config STACKDEPOT_ALWAYS_INIT
724 bool
725 select STACKDEPOT
726 help
727 Always initialize stack depot during early boot
728
729config STACKDEPOT_MAX_FRAMES
730 int "Maximum number of frames in trace saved in stack depot"
731 range 1 256
732 default 64
733 depends on STACKDEPOT
734
735config REF_TRACKER
736 bool
737 depends on STACKTRACE_SUPPORT
738 select STACKDEPOT
739
740config SBITMAP
741 bool
742
743config PARMAN
744 tristate "parman" if COMPILE_TEST
745
746config OBJAGG
747 tristate "objagg" if COMPILE_TEST
748
749config LWQ_TEST
750 bool "Boot-time test for lwq queuing"
751 help
752 Run boot-time test of light-weight queuing.
753
754endmenu
755
756config GENERIC_IOREMAP
757 bool
758
759config GENERIC_LIB_ASHLDI3
760 bool
761
762config GENERIC_LIB_ASHRDI3
763 bool
764
765config GENERIC_LIB_LSHRDI3
766 bool
767
768config GENERIC_LIB_MULDI3
769 bool
770
771config GENERIC_LIB_CMPDI2
772 bool
773
774config GENERIC_LIB_UCMPDI2
775 bool
776
777config GENERIC_LIB_DEVMEM_IS_ALLOWED
778 bool
779
780config PLDMFW
781 bool
782 default n
783
784config ASN1_ENCODER
785 tristate
786
787config POLYNOMIAL
788 tristate
789
790config FIRMWARE_TABLE
791 bool
792
793config UNION_FIND
794 bool
795
796config MIN_HEAP
797 bool
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 ARCH_USE_CMPXCHG_LOCKREF
57 bool
58
59config ARCH_HAS_FAST_MULTIPLIER
60 bool
61
62config CRC_CCITT
63 tristate "CRC-CCITT functions"
64 help
65 This option is provided for the case where no in-kernel-tree
66 modules require CRC-CCITT functions, but a module built outside
67 the kernel tree does. Such modules that use library CRC-CCITT
68 functions require M here.
69
70config CRC16
71 tristate "CRC16 functions"
72 help
73 This option is provided for the case where no in-kernel-tree
74 modules require CRC16 functions, but a module built outside
75 the kernel tree does. Such modules that use library CRC16
76 functions require M here.
77
78config CRC_T10DIF
79 tristate "CRC calculation for the T10 Data Integrity Field"
80 select CRYPTO
81 select CRYPTO_CRCT10DIF
82 help
83 This option is only needed if a module that's not in the
84 kernel tree needs to calculate CRC checks for use with the
85 SCSI data integrity subsystem.
86
87config CRC_ITU_T
88 tristate "CRC ITU-T V.41 functions"
89 help
90 This option is provided for the case where no in-kernel-tree
91 modules require CRC ITU-T V.41 functions, but a module built outside
92 the kernel tree does. Such modules that use library CRC ITU-T V.41
93 functions require M here.
94
95config CRC32
96 tristate "CRC32/CRC32c functions"
97 default y
98 select BITREVERSE
99 help
100 This option is provided for the case where no in-kernel-tree
101 modules require CRC32/CRC32c functions, but a module built outside
102 the kernel tree does. Such modules that use library CRC32/CRC32c
103 functions require M here.
104
105config CRC32_SELFTEST
106 bool "CRC32 perform self test on init"
107 default n
108 depends on CRC32
109 help
110 This option enables the CRC32 library functions to perform a
111 self test on initialization. The self test computes crc32_le
112 and crc32_be over byte strings with random alignment and length
113 and computes the total elapsed time and number of bytes processed.
114
115choice
116 prompt "CRC32 implementation"
117 depends on CRC32
118 default CRC32_SLICEBY8
119 help
120 This option allows a kernel builder to override the default choice
121 of CRC32 algorithm. Choose the default ("slice by 8") unless you
122 know that you need one of the others.
123
124config CRC32_SLICEBY8
125 bool "Slice by 8 bytes"
126 help
127 Calculate checksum 8 bytes at a time with a clever slicing algorithm.
128 This is the fastest algorithm, but comes with a 8KiB lookup table.
129 Most modern processors have enough cache to hold this table without
130 thrashing the cache.
131
132 This is the default implementation choice. Choose this one unless
133 you have a good reason not to.
134
135config CRC32_SLICEBY4
136 bool "Slice by 4 bytes"
137 help
138 Calculate checksum 4 bytes at a time with a clever slicing algorithm.
139 This is a bit slower than slice by 8, but has a smaller 4KiB lookup
140 table.
141
142 Only choose this option if you know what you are doing.
143
144config CRC32_SARWATE
145 bool "Sarwate's Algorithm (one byte at a time)"
146 help
147 Calculate checksum a byte at a time using Sarwate's algorithm. This
148 is not particularly fast, but has a small 256 byte lookup table.
149
150 Only choose this option if you know what you are doing.
151
152config CRC32_BIT
153 bool "Classic Algorithm (one bit at a time)"
154 help
155 Calculate checksum one bit at a time. This is VERY slow, but has
156 no lookup table. This is provided as a debugging option.
157
158 Only choose this option if you are debugging crc32.
159
160endchoice
161
162config CRC7
163 tristate "CRC7 functions"
164 help
165 This option is provided for the case where no in-kernel-tree
166 modules require CRC7 functions, but a module built outside
167 the kernel tree does. Such modules that use library CRC7
168 functions require M here.
169
170config LIBCRC32C
171 tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check"
172 select CRYPTO
173 select CRYPTO_CRC32C
174 help
175 This option is provided for the case where no in-kernel-tree
176 modules require CRC32c functions, but a module built outside the
177 kernel tree does. Such modules that use library CRC32c functions
178 require M here. See Castagnoli93.
179 Module will be libcrc32c.
180
181config CRC8
182 tristate "CRC8 function"
183 help
184 This option provides CRC8 function. Drivers may select this
185 when they need to do cyclic redundancy check according CRC8
186 algorithm. Module will be called crc8.
187
188config AUDIT_GENERIC
189 bool
190 depends on AUDIT && !AUDIT_ARCH
191 default y
192
193config AUDIT_ARCH_COMPAT_GENERIC
194 bool
195 default n
196
197config AUDIT_COMPAT_GENERIC
198 bool
199 depends on AUDIT_GENERIC && AUDIT_ARCH_COMPAT_GENERIC && COMPAT
200 default y
201
202config RANDOM32_SELFTEST
203 bool "PRNG perform self test on init"
204 default n
205 help
206 This option enables the 32 bit PRNG library functions to perform a
207 self test on initialization.
208
209#
210# compression support is select'ed if needed
211#
212config 842_COMPRESS
213 select CRC32
214 tristate
215
216config 842_DECOMPRESS
217 select CRC32
218 tristate
219
220config ZLIB_INFLATE
221 tristate
222
223config ZLIB_DEFLATE
224 tristate
225 select BITREVERSE
226
227config LZO_COMPRESS
228 tristate
229
230config LZO_DECOMPRESS
231 tristate
232
233config LZ4_COMPRESS
234 tristate
235
236config LZ4HC_COMPRESS
237 tristate
238
239config LZ4_DECOMPRESS
240 tristate
241
242source "lib/xz/Kconfig"
243
244#
245# These all provide a common interface (hence the apparent duplication with
246# ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.)
247#
248config DECOMPRESS_GZIP
249 select ZLIB_INFLATE
250 tristate
251
252config DECOMPRESS_BZIP2
253 tristate
254
255config DECOMPRESS_LZMA
256 tristate
257
258config DECOMPRESS_XZ
259 select XZ_DEC
260 tristate
261
262config DECOMPRESS_LZO
263 select LZO_DECOMPRESS
264 tristate
265
266config DECOMPRESS_LZ4
267 select LZ4_DECOMPRESS
268 tristate
269
270#
271# Generic allocator support is selected if needed
272#
273config GENERIC_ALLOCATOR
274 bool
275
276#
277# reed solomon support is select'ed if needed
278#
279config REED_SOLOMON
280 tristate
281
282config REED_SOLOMON_ENC8
283 bool
284
285config REED_SOLOMON_DEC8
286 bool
287
288config REED_SOLOMON_ENC16
289 bool
290
291config REED_SOLOMON_DEC16
292 bool
293
294#
295# BCH support is selected if needed
296#
297config BCH
298 tristate
299
300config BCH_CONST_PARAMS
301 bool
302 help
303 Drivers may select this option to force specific constant
304 values for parameters 'm' (Galois field order) and 't'
305 (error correction capability). Those specific values must
306 be set by declaring default values for symbols BCH_CONST_M
307 and BCH_CONST_T.
308 Doing so will enable extra compiler optimizations,
309 improving encoding and decoding performance up to 2x for
310 usual (m,t) values (typically such that m*t < 200).
311 When this option is selected, the BCH library supports
312 only a single (m,t) configuration. This is mainly useful
313 for NAND flash board drivers requiring known, fixed BCH
314 parameters.
315
316config BCH_CONST_M
317 int
318 range 5 15
319 help
320 Constant value for Galois field order 'm'. If 'k' is the
321 number of data bits to protect, 'm' should be chosen such
322 that (k + m*t) <= 2**m - 1.
323 Drivers should declare a default value for this symbol if
324 they select option BCH_CONST_PARAMS.
325
326config BCH_CONST_T
327 int
328 help
329 Constant value for error correction capability in bits 't'.
330 Drivers should declare a default value for this symbol if
331 they select option BCH_CONST_PARAMS.
332
333#
334# Textsearch support is select'ed if needed
335#
336config TEXTSEARCH
337 bool
338
339config TEXTSEARCH_KMP
340 tristate
341
342config TEXTSEARCH_BM
343 tristate
344
345config TEXTSEARCH_FSM
346 tristate
347
348config BTREE
349 bool
350
351config INTERVAL_TREE
352 bool
353 help
354 Simple, embeddable, interval-tree. Can find the start of an
355 overlapping range in log(n) time and then iterate over all
356 overlapping nodes. The algorithm is implemented as an
357 augmented rbtree.
358
359 See:
360
361 Documentation/rbtree.txt
362
363 for more information.
364
365config ASSOCIATIVE_ARRAY
366 bool
367 help
368 Generic associative array. Can be searched and iterated over whilst
369 it is being modified. It is also reasonably quick to search and
370 modify. The algorithms are non-recursive, and the trees are highly
371 capacious.
372
373 See:
374
375 Documentation/assoc_array.txt
376
377 for more information.
378
379config HAS_IOMEM
380 bool
381 depends on !NO_IOMEM
382 select GENERIC_IO
383 default y
384
385config HAS_IOPORT_MAP
386 bool
387 depends on HAS_IOMEM && !NO_IOPORT_MAP
388 default y
389
390config HAS_DMA
391 bool
392 depends on !NO_DMA
393 default y
394
395config CHECK_SIGNATURE
396 bool
397
398config CPUMASK_OFFSTACK
399 bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
400 help
401 Use dynamic allocation for cpumask_var_t, instead of putting
402 them on the stack. This is a bit more expensive, but avoids
403 stack overflow.
404
405config CPU_RMAP
406 bool
407 depends on SMP
408
409config DQL
410 bool
411
412config GLOB
413 bool
414# This actually supports modular compilation, but the module overhead
415# is ridiculous for the amount of code involved. Until an out-of-tree
416# driver asks for it, we'll just link it directly it into the kernel
417# when required. Since we're ignoring out-of-tree users, there's also
418# no need bother prompting for a manual decision:
419# prompt "glob_match() function"
420 help
421 This option provides a glob_match function for performing
422 simple text pattern matching. It originated in the ATA code
423 to blacklist particular drive models, but other device drivers
424 may need similar functionality.
425
426 All drivers in the Linux kernel tree that require this function
427 should automatically select this option. Say N unless you
428 are compiling an out-of tree driver which tells you that it
429 depends on this.
430
431config GLOB_SELFTEST
432 bool "glob self-test on init"
433 default n
434 depends on GLOB
435 help
436 This option enables a simple self-test of the glob_match
437 function on startup. It is primarily useful for people
438 working on the code to ensure they haven't introduced any
439 regressions.
440
441 It only adds a little bit of code and slows kernel boot (or
442 module load) by a small amount, so you're welcome to play with
443 it, but you probably don't need it.
444
445#
446# Netlink attribute parsing support is select'ed if needed
447#
448config NLATTR
449 bool
450
451#
452# Generic 64-bit atomic support is selected if needed
453#
454config GENERIC_ATOMIC64
455 bool
456
457config ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
458 def_bool y if GENERIC_ATOMIC64
459
460config LRU_CACHE
461 tristate
462
463config CLZ_TAB
464 bool
465
466config CORDIC
467 tristate "CORDIC algorithm"
468 help
469 This option provides an implementation of the CORDIC algorithm;
470 calculations are in fixed point. Module will be called cordic.
471
472config DDR
473 bool "JEDEC DDR data"
474 help
475 Data from JEDEC specs for DDR SDRAM memories,
476 particularly the AC timing parameters and addressing
477 information. This data is useful for drivers handling
478 DDR SDRAM controllers.
479
480config IRQ_POLL
481 bool "IRQ polling library"
482 help
483 Helper library to poll interrupt mitigation using polling.
484
485config MPILIB
486 tristate
487 select CLZ_TAB
488 help
489 Multiprecision maths library from GnuPG.
490 It is used to implement RSA digital signature verification,
491 which is used by IMA/EVM digital signature extension.
492
493config SIGNATURE
494 tristate
495 depends on KEYS
496 select CRYPTO
497 select CRYPTO_SHA1
498 select MPILIB
499 help
500 Digital signature verification. Currently only RSA is supported.
501 Implementation is done using GnuPG MPI library
502
503#
504# libfdt files, only selected if needed.
505#
506config LIBFDT
507 bool
508
509config OID_REGISTRY
510 tristate
511 help
512 Enable fast lookup object identifier registry.
513
514config UCS2_STRING
515 tristate
516
517source "lib/fonts/Kconfig"
518
519config SG_SPLIT
520 def_bool n
521 help
522 Provides a helper to split scatterlists into chunks, each chunk being
523 a scatterlist. This should be selected by a driver or an API which
524 whishes to split a scatterlist amongst multiple DMA channels.
525
526#
527# sg chaining option
528#
529
530config ARCH_HAS_SG_CHAIN
531 def_bool n
532
533config ARCH_HAS_PMEM_API
534 bool
535
536config ARCH_HAS_MMIO_FLUSH
537 bool
538
539config STACKDEPOT
540 bool
541 select STACKTRACE
542
543endmenu