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Linus Torvalds1da177e2005-04-16 15:20:36 -07001comment "Processor Type"
2
Linus Torvalds1da177e2005-04-16 15:20:36 -07003# Select CPU types depending on the architecture selected. This selects
4# which CPUs we support in the kernel image, and the compiler instruction
5# optimiser behaviour.
6
7# ARM610
8config CPU_ARM610
Russell Kingc7508152008-10-26 10:55:14 +00009 bool "Support ARM610 processor" if ARCH_RPC
Linus Torvalds1da177e2005-04-16 15:20:36 -070010 select CPU_32v3
11 select CPU_CACHE_V3
12 select CPU_CACHE_VIVT
Hyok S. Choifefdaa02006-09-26 17:36:37 +090013 select CPU_CP15_MMU
Hyok S. Choif9c21a62006-06-21 22:26:29 +010014 select CPU_COPY_V3 if MMU
15 select CPU_TLB_V3 if MMU
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +010016 select CPU_PABRT_LEGACY
Linus Torvalds1da177e2005-04-16 15:20:36 -070017 help
18 The ARM610 is the successor to the ARM3 processor
19 and was produced by VLSI Technology Inc.
20
21 Say Y if you want support for the ARM610 processor.
22 Otherwise, say N.
23
Hyok S. Choi07e0da72006-09-26 17:37:36 +090024# ARM7TDMI
25config CPU_ARM7TDMI
26 bool "Support ARM7TDMI processor"
Russell King6b237a32006-09-27 17:44:39 +010027 depends on !MMU
Hyok S. Choi07e0da72006-09-26 17:37:36 +090028 select CPU_32v4T
29 select CPU_ABRT_LV4T
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +010030 select CPU_PABRT_LEGACY
Hyok S. Choi07e0da72006-09-26 17:37:36 +090031 select CPU_CACHE_V4
32 help
33 A 32-bit RISC microprocessor based on the ARM7 processor core
34 which has no memory control unit and cache.
35
36 Say Y if you want support for the ARM7TDMI processor.
37 Otherwise, say N.
38
Linus Torvalds1da177e2005-04-16 15:20:36 -070039# ARM710
40config CPU_ARM710
Russell Kingc7508152008-10-26 10:55:14 +000041 bool "Support ARM710 processor" if ARCH_RPC
Linus Torvalds1da177e2005-04-16 15:20:36 -070042 select CPU_32v3
43 select CPU_CACHE_V3
44 select CPU_CACHE_VIVT
Hyok S. Choifefdaa02006-09-26 17:36:37 +090045 select CPU_CP15_MMU
Hyok S. Choif9c21a62006-06-21 22:26:29 +010046 select CPU_COPY_V3 if MMU
47 select CPU_TLB_V3 if MMU
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +010048 select CPU_PABRT_LEGACY
Linus Torvalds1da177e2005-04-16 15:20:36 -070049 help
50 A 32-bit RISC microprocessor based on the ARM7 processor core
51 designed by Advanced RISC Machines Ltd. The ARM710 is the
52 successor to the ARM610 processor. It was released in
53 July 1994 by VLSI Technology Inc.
54
55 Say Y if you want support for the ARM710 processor.
56 Otherwise, say N.
57
58# ARM720T
59config CPU_ARM720T
Russell Kingc7508152008-10-26 10:55:14 +000060 bool "Support ARM720T processor" if ARCH_INTEGRATOR
Lennert Buytenhek260e98e2006-08-28 12:51:20 +010061 select CPU_32v4T
Linus Torvalds1da177e2005-04-16 15:20:36 -070062 select CPU_ABRT_LV4T
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +010063 select CPU_PABRT_LEGACY
Linus Torvalds1da177e2005-04-16 15:20:36 -070064 select CPU_CACHE_V4
65 select CPU_CACHE_VIVT
Hyok S. Choifefdaa02006-09-26 17:36:37 +090066 select CPU_CP15_MMU
Hyok S. Choif9c21a62006-06-21 22:26:29 +010067 select CPU_COPY_V4WT if MMU
68 select CPU_TLB_V4WT if MMU
Linus Torvalds1da177e2005-04-16 15:20:36 -070069 help
70 A 32-bit RISC processor with 8kByte Cache, Write Buffer and
71 MMU built around an ARM7TDMI core.
72
73 Say Y if you want support for the ARM720T processor.
74 Otherwise, say N.
75
Hyok S. Choib731c312006-09-26 17:37:50 +090076# ARM740T
77config CPU_ARM740T
78 bool "Support ARM740T processor" if ARCH_INTEGRATOR
Russell King6b237a32006-09-27 17:44:39 +010079 depends on !MMU
Hyok S. Choib731c312006-09-26 17:37:50 +090080 select CPU_32v4T
81 select CPU_ABRT_LV4T
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +010082 select CPU_PABRT_LEGACY
Hyok S. Choib731c312006-09-26 17:37:50 +090083 select CPU_CACHE_V3 # although the core is v4t
84 select CPU_CP15_MPU
85 help
86 A 32-bit RISC processor with 8KB cache or 4KB variants,
87 write buffer and MPU(Protection Unit) built around
88 an ARM7TDMI core.
89
90 Say Y if you want support for the ARM740T processor.
91 Otherwise, say N.
92
Hyok S. Choi43f5f012006-09-26 17:38:05 +090093# ARM9TDMI
94config CPU_ARM9TDMI
95 bool "Support ARM9TDMI processor"
Russell King6b237a32006-09-27 17:44:39 +010096 depends on !MMU
Hyok S. Choi43f5f012006-09-26 17:38:05 +090097 select CPU_32v4T
Hyok S. Choi0f45d7f2006-09-28 21:46:16 +090098 select CPU_ABRT_NOMMU
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +010099 select CPU_PABRT_LEGACY
Hyok S. Choi43f5f012006-09-26 17:38:05 +0900100 select CPU_CACHE_V4
101 help
102 A 32-bit RISC microprocessor based on the ARM9 processor core
103 which has no memory control unit and cache.
104
105 Say Y if you want support for the ARM9TDMI processor.
106 Otherwise, say N.
107
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108# ARM920T
109config CPU_ARM920T
Russell Kingc7508152008-10-26 10:55:14 +0000110 bool "Support ARM920T processor" if ARCH_INTEGRATOR
Lennert Buytenhek260e98e2006-08-28 12:51:20 +0100111 select CPU_32v4T
Linus Torvalds1da177e2005-04-16 15:20:36 -0700112 select CPU_ABRT_EV4T
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100113 select CPU_PABRT_LEGACY
Linus Torvalds1da177e2005-04-16 15:20:36 -0700114 select CPU_CACHE_V4WT
115 select CPU_CACHE_VIVT
Hyok S. Choifefdaa02006-09-26 17:36:37 +0900116 select CPU_CP15_MMU
Hyok S. Choif9c21a62006-06-21 22:26:29 +0100117 select CPU_COPY_V4WB if MMU
118 select CPU_TLB_V4WBI if MMU
Linus Torvalds1da177e2005-04-16 15:20:36 -0700119 help
120 The ARM920T is licensed to be produced by numerous vendors,
Hartley Sweetenc768e672009-10-21 02:27:01 +0100121 and is used in the Cirrus EP93xx and the Samsung S3C2410.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700122
123 Say Y if you want support for the ARM920T processor.
124 Otherwise, say N.
125
126# ARM922T
127config CPU_ARM922T
128 bool "Support ARM922T processor" if ARCH_INTEGRATOR
Lennert Buytenhek260e98e2006-08-28 12:51:20 +0100129 select CPU_32v4T
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130 select CPU_ABRT_EV4T
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100131 select CPU_PABRT_LEGACY
Linus Torvalds1da177e2005-04-16 15:20:36 -0700132 select CPU_CACHE_V4WT
133 select CPU_CACHE_VIVT
Hyok S. Choifefdaa02006-09-26 17:36:37 +0900134 select CPU_CP15_MMU
Hyok S. Choif9c21a62006-06-21 22:26:29 +0100135 select CPU_COPY_V4WB if MMU
136 select CPU_TLB_V4WBI if MMU
Linus Torvalds1da177e2005-04-16 15:20:36 -0700137 help
138 The ARM922T is a version of the ARM920T, but with smaller
139 instruction and data caches. It is used in Altera's
Andrew Victorc53c9cf2007-05-11 21:01:28 +0100140 Excalibur XA device family and Micrel's KS8695 Centaur.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141
142 Say Y if you want support for the ARM922T processor.
143 Otherwise, say N.
144
145# ARM925T
146config CPU_ARM925T
Tony Lindgrenb288f752005-07-10 19:58:08 +0100147 bool "Support ARM925T processor" if ARCH_OMAP1
Lennert Buytenhek260e98e2006-08-28 12:51:20 +0100148 select CPU_32v4T
Linus Torvalds1da177e2005-04-16 15:20:36 -0700149 select CPU_ABRT_EV4T
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100150 select CPU_PABRT_LEGACY
Linus Torvalds1da177e2005-04-16 15:20:36 -0700151 select CPU_CACHE_V4WT
152 select CPU_CACHE_VIVT
Hyok S. Choifefdaa02006-09-26 17:36:37 +0900153 select CPU_CP15_MMU
Hyok S. Choif9c21a62006-06-21 22:26:29 +0100154 select CPU_COPY_V4WB if MMU
155 select CPU_TLB_V4WBI if MMU
Linus Torvalds1da177e2005-04-16 15:20:36 -0700156 help
157 The ARM925T is a mix between the ARM920T and ARM926T, but with
158 different instruction and data caches. It is used in TI's OMAP
159 device family.
160
161 Say Y if you want support for the ARM925T processor.
162 Otherwise, say N.
163
164# ARM926T
165config CPU_ARM926T
Russell Kingc7508152008-10-26 10:55:14 +0000166 bool "Support ARM926T processor" if ARCH_INTEGRATOR || MACH_REALVIEW_EB
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167 select CPU_32v5
168 select CPU_ABRT_EV5TJ
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100169 select CPU_PABRT_LEGACY
Linus Torvalds1da177e2005-04-16 15:20:36 -0700170 select CPU_CACHE_VIVT
Hyok S. Choifefdaa02006-09-26 17:36:37 +0900171 select CPU_CP15_MMU
Hyok S. Choif9c21a62006-06-21 22:26:29 +0100172 select CPU_COPY_V4WB if MMU
173 select CPU_TLB_V4WBI if MMU
Linus Torvalds1da177e2005-04-16 15:20:36 -0700174 help
175 This is a variant of the ARM920. It has slightly different
176 instruction sequences for cache and TLB operations. Curiously,
177 there is no documentation on it at the ARM corporate website.
178
179 Say Y if you want support for the ARM926T processor.
180 Otherwise, say N.
181
Paulius Zaleckas28853ac2009-03-25 13:10:01 +0200182# FA526
183config CPU_FA526
184 bool
185 select CPU_32v4
186 select CPU_ABRT_EV4
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100187 select CPU_PABRT_LEGACY
Paulius Zaleckas28853ac2009-03-25 13:10:01 +0200188 select CPU_CACHE_VIVT
189 select CPU_CP15_MMU
190 select CPU_CACHE_FA
191 select CPU_COPY_FA if MMU
192 select CPU_TLB_FA if MMU
193 help
194 The FA526 is a version of the ARMv4 compatible processor with
195 Branch Target Buffer, Unified TLB and cache line size 16.
196
197 Say Y if you want support for the FA526 processor.
198 Otherwise, say N.
199
Hyok S. Choid60674e2006-09-26 17:38:18 +0900200# ARM940T
201config CPU_ARM940T
202 bool "Support ARM940T processor" if ARCH_INTEGRATOR
Russell King6b237a32006-09-27 17:44:39 +0100203 depends on !MMU
Hyok S. Choid60674e2006-09-26 17:38:18 +0900204 select CPU_32v4T
Hyok S. Choi0f45d7f2006-09-28 21:46:16 +0900205 select CPU_ABRT_NOMMU
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100206 select CPU_PABRT_LEGACY
Hyok S. Choid60674e2006-09-26 17:38:18 +0900207 select CPU_CACHE_VIVT
208 select CPU_CP15_MPU
209 help
210 ARM940T is a member of the ARM9TDMI family of general-
Matt LaPlante3cb2fcc2006-11-30 05:22:59 +0100211 purpose microprocessors with MPU and separate 4KB
Hyok S. Choid60674e2006-09-26 17:38:18 +0900212 instruction and 4KB data cases, each with a 4-word line
213 length.
214
215 Say Y if you want support for the ARM940T processor.
216 Otherwise, say N.
217
Hyok S. Choif37f46e2006-09-26 17:38:32 +0900218# ARM946E-S
219config CPU_ARM946E
220 bool "Support ARM946E-S processor" if ARCH_INTEGRATOR
Russell King6b237a32006-09-27 17:44:39 +0100221 depends on !MMU
Hyok S. Choif37f46e2006-09-26 17:38:32 +0900222 select CPU_32v5
Hyok S. Choi0f45d7f2006-09-28 21:46:16 +0900223 select CPU_ABRT_NOMMU
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100224 select CPU_PABRT_LEGACY
Hyok S. Choif37f46e2006-09-26 17:38:32 +0900225 select CPU_CACHE_VIVT
226 select CPU_CP15_MPU
227 help
228 ARM946E-S is a member of the ARM9E-S family of high-
229 performance, 32-bit system-on-chip processor solutions.
230 The TCM and ARMv5TE 32-bit instruction set is supported.
231
232 Say Y if you want support for the ARM946E-S processor.
233 Otherwise, say N.
234
Linus Torvalds1da177e2005-04-16 15:20:36 -0700235# ARM1020 - needs validating
236config CPU_ARM1020
Russell Kingc7508152008-10-26 10:55:14 +0000237 bool "Support ARM1020T (rev 0) processor" if ARCH_INTEGRATOR
Linus Torvalds1da177e2005-04-16 15:20:36 -0700238 select CPU_32v5
239 select CPU_ABRT_EV4T
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100240 select CPU_PABRT_LEGACY
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241 select CPU_CACHE_V4WT
242 select CPU_CACHE_VIVT
Hyok S. Choifefdaa02006-09-26 17:36:37 +0900243 select CPU_CP15_MMU
Hyok S. Choif9c21a62006-06-21 22:26:29 +0100244 select CPU_COPY_V4WB if MMU
245 select CPU_TLB_V4WBI if MMU
Linus Torvalds1da177e2005-04-16 15:20:36 -0700246 help
247 The ARM1020 is the 32K cached version of the ARM10 processor,
248 with an addition of a floating-point unit.
249
250 Say Y if you want support for the ARM1020 processor.
251 Otherwise, say N.
252
253# ARM1020E - needs validating
254config CPU_ARM1020E
Russell Kingc7508152008-10-26 10:55:14 +0000255 bool "Support ARM1020E processor" if ARCH_INTEGRATOR
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256 select CPU_32v5
257 select CPU_ABRT_EV4T
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100258 select CPU_PABRT_LEGACY
Linus Torvalds1da177e2005-04-16 15:20:36 -0700259 select CPU_CACHE_V4WT
260 select CPU_CACHE_VIVT
Hyok S. Choifefdaa02006-09-26 17:36:37 +0900261 select CPU_CP15_MMU
Hyok S. Choif9c21a62006-06-21 22:26:29 +0100262 select CPU_COPY_V4WB if MMU
263 select CPU_TLB_V4WBI if MMU
Linus Torvalds1da177e2005-04-16 15:20:36 -0700264 depends on n
265
266# ARM1022E
267config CPU_ARM1022
Russell Kingc7508152008-10-26 10:55:14 +0000268 bool "Support ARM1022E processor" if ARCH_INTEGRATOR
Linus Torvalds1da177e2005-04-16 15:20:36 -0700269 select CPU_32v5
270 select CPU_ABRT_EV4T
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100271 select CPU_PABRT_LEGACY
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 select CPU_CACHE_VIVT
Hyok S. Choifefdaa02006-09-26 17:36:37 +0900273 select CPU_CP15_MMU
Hyok S. Choif9c21a62006-06-21 22:26:29 +0100274 select CPU_COPY_V4WB if MMU # can probably do better
275 select CPU_TLB_V4WBI if MMU
Linus Torvalds1da177e2005-04-16 15:20:36 -0700276 help
277 The ARM1022E is an implementation of the ARMv5TE architecture
278 based upon the ARM10 integer core with a 16KiB L1 Harvard cache,
279 embedded trace macrocell, and a floating-point unit.
280
281 Say Y if you want support for the ARM1022E processor.
282 Otherwise, say N.
283
284# ARM1026EJ-S
285config CPU_ARM1026
Russell Kingc7508152008-10-26 10:55:14 +0000286 bool "Support ARM1026EJ-S processor" if ARCH_INTEGRATOR
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 select CPU_32v5
288 select CPU_ABRT_EV5T # But need Jazelle, but EV5TJ ignores bit 10
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100289 select CPU_PABRT_LEGACY
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290 select CPU_CACHE_VIVT
Hyok S. Choifefdaa02006-09-26 17:36:37 +0900291 select CPU_CP15_MMU
Hyok S. Choif9c21a62006-06-21 22:26:29 +0100292 select CPU_COPY_V4WB if MMU # can probably do better
293 select CPU_TLB_V4WBI if MMU
Linus Torvalds1da177e2005-04-16 15:20:36 -0700294 help
295 The ARM1026EJ-S is an implementation of the ARMv5TEJ architecture
296 based upon the ARM10 integer core.
297
298 Say Y if you want support for the ARM1026EJ-S processor.
299 Otherwise, say N.
300
301# SA110
302config CPU_SA110
Russell Kingc7508152008-10-26 10:55:14 +0000303 bool "Support StrongARM(R) SA-110 processor" if ARCH_RPC
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304 select CPU_32v3 if ARCH_RPC
305 select CPU_32v4 if !ARCH_RPC
306 select CPU_ABRT_EV4
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100307 select CPU_PABRT_LEGACY
Linus Torvalds1da177e2005-04-16 15:20:36 -0700308 select CPU_CACHE_V4WB
309 select CPU_CACHE_VIVT
Hyok S. Choifefdaa02006-09-26 17:36:37 +0900310 select CPU_CP15_MMU
Hyok S. Choif9c21a62006-06-21 22:26:29 +0100311 select CPU_COPY_V4WB if MMU
312 select CPU_TLB_V4WB if MMU
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313 help
314 The Intel StrongARM(R) SA-110 is a 32-bit microprocessor and
315 is available at five speeds ranging from 100 MHz to 233 MHz.
316 More information is available at
317 <http://developer.intel.com/design/strong/sa110.htm>.
318
319 Say Y if you want support for the SA-110 processor.
320 Otherwise, say N.
321
322# SA1100
323config CPU_SA1100
324 bool
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325 select CPU_32v4
326 select CPU_ABRT_EV4
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100327 select CPU_PABRT_LEGACY
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 select CPU_CACHE_V4WB
329 select CPU_CACHE_VIVT
Hyok S. Choifefdaa02006-09-26 17:36:37 +0900330 select CPU_CP15_MMU
Hyok S. Choif9c21a62006-06-21 22:26:29 +0100331 select CPU_TLB_V4WB if MMU
Linus Torvalds1da177e2005-04-16 15:20:36 -0700332
333# XScale
334config CPU_XSCALE
335 bool
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336 select CPU_32v5
337 select CPU_ABRT_EV5T
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100338 select CPU_PABRT_LEGACY
Linus Torvalds1da177e2005-04-16 15:20:36 -0700339 select CPU_CACHE_VIVT
Hyok S. Choifefdaa02006-09-26 17:36:37 +0900340 select CPU_CP15_MMU
Hyok S. Choif9c21a62006-06-21 22:26:29 +0100341 select CPU_TLB_V4WBI if MMU
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342
Lennert Buytenhek23bdf862006-03-28 21:00:40 +0100343# XScale Core Version 3
344config CPU_XSC3
345 bool
Lennert Buytenhek23bdf862006-03-28 21:00:40 +0100346 select CPU_32v5
347 select CPU_ABRT_EV5T
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100348 select CPU_PABRT_LEGACY
Lennert Buytenhek23bdf862006-03-28 21:00:40 +0100349 select CPU_CACHE_VIVT
Hyok S. Choifefdaa02006-09-26 17:36:37 +0900350 select CPU_CP15_MMU
Hyok S. Choif9c21a62006-06-21 22:26:29 +0100351 select CPU_TLB_V4WBI if MMU
Lennert Buytenhek23bdf862006-03-28 21:00:40 +0100352 select IO_36
353
Eric Miao49cbe782009-01-20 14:15:18 +0800354# Marvell PJ1 (Mohawk)
355config CPU_MOHAWK
356 bool
357 select CPU_32v5
358 select CPU_ABRT_EV5T
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100359 select CPU_PABRT_LEGACY
Eric Miao49cbe782009-01-20 14:15:18 +0800360 select CPU_CACHE_VIVT
361 select CPU_CP15_MMU
362 select CPU_TLB_V4WBI if MMU
363 select CPU_COPY_V4WB if MMU
364
Assaf Hoffmane50d6402007-10-23 15:14:41 -0400365# Feroceon
366config CPU_FEROCEON
367 bool
Assaf Hoffmane50d6402007-10-23 15:14:41 -0400368 select CPU_32v5
369 select CPU_ABRT_EV5T
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100370 select CPU_PABRT_LEGACY
Assaf Hoffmane50d6402007-10-23 15:14:41 -0400371 select CPU_CACHE_VIVT
372 select CPU_CP15_MMU
Lennert Buytenhek0ed15072008-04-24 01:31:45 -0400373 select CPU_COPY_FEROCEON if MMU
Lennert Buytenhek99c6dc12008-06-22 22:45:04 +0200374 select CPU_TLB_FEROCEON if MMU
Assaf Hoffmane50d6402007-10-23 15:14:41 -0400375
Tzachi Perelsteind910a0a2007-11-06 10:35:40 +0200376config CPU_FEROCEON_OLD_ID
377 bool "Accept early Feroceon cores with an ARM926 ID"
378 depends on CPU_FEROCEON && !CPU_ARM926T
379 default y
380 help
381 This enables the usage of some old Feroceon cores
382 for which the CPU ID is equal to the ARM926 ID.
383 Relevant for Feroceon-1850 and early Feroceon-2850.
384
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385# ARMv6
386config CPU_V6
Saeed Bisharaedabd382009-08-06 15:12:43 +0300387 bool "Support ARM V6 processor" if ARCH_INTEGRATOR || MACH_REALVIEW_EB || MACH_REALVIEW_PBX || ARCH_DOVE
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388 select CPU_32v6
389 select CPU_ABRT_EV6
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100390 select CPU_PABRT_V6
Linus Torvalds1da177e2005-04-16 15:20:36 -0700391 select CPU_CACHE_V6
392 select CPU_CACHE_VIPT
Hyok S. Choifefdaa02006-09-26 17:36:37 +0900393 select CPU_CP15_MMU
Catalin Marinas7b4c9652007-07-20 11:42:57 +0100394 select CPU_HAS_ASID if MMU
Hyok S. Choif9c21a62006-06-21 22:26:29 +0100395 select CPU_COPY_V6 if MMU
396 select CPU_TLB_V6 if MMU
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397
Russell King4a5f79e2005-11-03 15:48:21 +0000398# ARMv6k
399config CPU_32v6K
400 bool "Support ARM V6K processor extensions" if !SMP
Catalin Marinas026b5ca2010-09-01 14:33:29 +0100401 depends on CPU_V6 || CPU_V7
Tony Lindgren1a28e3d2010-02-01 23:30:26 +0100402 default y if SMP && !(ARCH_MX3 || ARCH_OMAP2)
Russell King4a5f79e2005-11-03 15:48:21 +0000403 help
404 Say Y here if your ARMv6 processor supports the 'K' extension.
405 This enables the kernel to use some instructions not present
406 on previous processors, and as such a kernel build with this
407 enabled will not boot on processors with do not support these
408 instructions.
409
Catalin Marinas23688e92007-05-08 22:45:26 +0100410# ARMv7
411config CPU_V7
Colin Tuckley1b504bb2009-05-30 13:56:12 +0100412 bool "Support ARM V7 processor" if ARCH_INTEGRATOR || MACH_REALVIEW_EB || MACH_REALVIEW_PBX
Tony Lindgren1a28e3d2010-02-01 23:30:26 +0100413 select CPU_32v6K if !ARCH_OMAP2
Catalin Marinas23688e92007-05-08 22:45:26 +0100414 select CPU_32v7
415 select CPU_ABRT_EV7
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100416 select CPU_PABRT_V7
Catalin Marinas23688e92007-05-08 22:45:26 +0100417 select CPU_CACHE_V7
418 select CPU_CACHE_VIPT
419 select CPU_CP15_MMU
Catalin Marinas2eb8c822007-07-20 11:43:02 +0100420 select CPU_HAS_ASID if MMU
Catalin Marinas23688e92007-05-08 22:45:26 +0100421 select CPU_COPY_V6 if MMU
Catalin Marinas2ccdd1e2007-05-18 11:25:31 +0100422 select CPU_TLB_V7 if MMU
Catalin Marinas23688e92007-05-08 22:45:26 +0100423
Linus Torvalds1da177e2005-04-16 15:20:36 -0700424# Figure out what processor architecture version we should be using.
425# This defines the compiler instruction set which depends on the machine type.
426config CPU_32v3
427 bool
Russell King60b6cf62006-06-19 17:36:43 +0100428 select TLS_REG_EMUL if SMP || !MMU
Russell King48fa14f2006-03-16 14:52:33 +0000429 select NEEDS_SYSCALL_FOR_CMPXCHG if SMP
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430
431config CPU_32v4
432 bool
Russell King60b6cf62006-06-19 17:36:43 +0100433 select TLS_REG_EMUL if SMP || !MMU
Russell King48fa14f2006-03-16 14:52:33 +0000434 select NEEDS_SYSCALL_FOR_CMPXCHG if SMP
Linus Torvalds1da177e2005-04-16 15:20:36 -0700435
Lennert Buytenhek260e98e2006-08-28 12:51:20 +0100436config CPU_32v4T
437 bool
438 select TLS_REG_EMUL if SMP || !MMU
439 select NEEDS_SYSCALL_FOR_CMPXCHG if SMP
440
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441config CPU_32v5
442 bool
Russell King60b6cf62006-06-19 17:36:43 +0100443 select TLS_REG_EMUL if SMP || !MMU
Russell King48fa14f2006-03-16 14:52:33 +0000444 select NEEDS_SYSCALL_FOR_CMPXCHG if SMP
Linus Torvalds1da177e2005-04-16 15:20:36 -0700445
446config CPU_32v6
447 bool
Catalin Marinas367afaf2007-07-20 11:42:51 +0100448 select TLS_REG_EMUL if !CPU_32v6K && !MMU
Linus Torvalds1da177e2005-04-16 15:20:36 -0700449
Catalin Marinas23688e92007-05-08 22:45:26 +0100450config CPU_32v7
451 bool
452
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453# The abort model
Hyok S. Choi0f45d7f2006-09-28 21:46:16 +0900454config CPU_ABRT_NOMMU
455 bool
456
Linus Torvalds1da177e2005-04-16 15:20:36 -0700457config CPU_ABRT_EV4
458 bool
459
460config CPU_ABRT_EV4T
461 bool
462
463config CPU_ABRT_LV4T
464 bool
465
466config CPU_ABRT_EV5T
467 bool
468
469config CPU_ABRT_EV5TJ
470 bool
471
472config CPU_ABRT_EV6
473 bool
474
Catalin Marinas23688e92007-05-08 22:45:26 +0100475config CPU_ABRT_EV7
476 bool
477
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100478config CPU_PABRT_LEGACY
Paul Brook48d79272008-04-18 22:43:07 +0100479 bool
480
Kirill A. Shutemov4fb28472009-09-25 13:39:47 +0100481config CPU_PABRT_V6
482 bool
483
484config CPU_PABRT_V7
Paul Brook48d79272008-04-18 22:43:07 +0100485 bool
486
Linus Torvalds1da177e2005-04-16 15:20:36 -0700487# The cache model
488config CPU_CACHE_V3
489 bool
490
491config CPU_CACHE_V4
492 bool
493
494config CPU_CACHE_V4WT
495 bool
496
497config CPU_CACHE_V4WB
498 bool
499
500config CPU_CACHE_V6
501 bool
502
Catalin Marinas23688e92007-05-08 22:45:26 +0100503config CPU_CACHE_V7
504 bool
505
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506config CPU_CACHE_VIVT
507 bool
508
509config CPU_CACHE_VIPT
510 bool
511
Paulius Zaleckas28853ac2009-03-25 13:10:01 +0200512config CPU_CACHE_FA
513 bool
514
Hyok S. Choif9c21a62006-06-21 22:26:29 +0100515if MMU
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516# The copy-page model
517config CPU_COPY_V3
518 bool
519
520config CPU_COPY_V4WT
521 bool
522
523config CPU_COPY_V4WB
524 bool
525
Lennert Buytenhek0ed15072008-04-24 01:31:45 -0400526config CPU_COPY_FEROCEON
527 bool
528
Paulius Zaleckas28853ac2009-03-25 13:10:01 +0200529config CPU_COPY_FA
530 bool
531
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532config CPU_COPY_V6
533 bool
534
535# This selects the TLB model
536config CPU_TLB_V3
537 bool
538 help
539 ARM Architecture Version 3 TLB.
540
541config CPU_TLB_V4WT
542 bool
543 help
544 ARM Architecture Version 4 TLB with writethrough cache.
545
546config CPU_TLB_V4WB
547 bool
548 help
549 ARM Architecture Version 4 TLB with writeback cache.
550
551config CPU_TLB_V4WBI
552 bool
553 help
554 ARM Architecture Version 4 TLB with writeback cache and invalidate
555 instruction cache entry.
556
Lennert Buytenhek99c6dc12008-06-22 22:45:04 +0200557config CPU_TLB_FEROCEON
558 bool
559 help
560 Feroceon TLB (v4wbi with non-outer-cachable page table walks).
561
Paulius Zaleckas28853ac2009-03-25 13:10:01 +0200562config CPU_TLB_FA
563 bool
564 help
565 Faraday ARM FA526 architecture, unified TLB with writeback cache
566 and invalidate instruction cache entry. Branch target buffer is
567 also supported.
568
Linus Torvalds1da177e2005-04-16 15:20:36 -0700569config CPU_TLB_V6
570 bool
571
Catalin Marinas2ccdd1e2007-05-18 11:25:31 +0100572config CPU_TLB_V7
573 bool
574
Dave Estese220ba62009-08-11 17:58:49 -0400575config VERIFY_PERMISSION_FAULT
576 bool
Hyok S. Choif9c21a62006-06-21 22:26:29 +0100577endif
578
Russell King516793c2007-05-17 10:19:23 +0100579config CPU_HAS_ASID
580 bool
581 help
582 This indicates whether the CPU has the ASID register; used to
583 tag TLB and possibly cache entries.
584
Hyok S. Choifefdaa02006-09-26 17:36:37 +0900585config CPU_CP15
586 bool
587 help
588 Processor has the CP15 register.
589
590config CPU_CP15_MMU
591 bool
592 select CPU_CP15
593 help
594 Processor has the CP15 register, which has MMU related registers.
595
596config CPU_CP15_MPU
597 bool
598 select CPU_CP15
599 help
600 Processor has the CP15 register, which has MPU related registers.
601
Catalin Marinas247055a2010-09-13 16:03:21 +0100602config CPU_USE_DOMAINS
603 bool
604 depends on MMU
605 default y if !CPU_32v6K
606 help
607 This option enables or disables the use of domain switching
608 via the set_fs() function.
609
Lennert Buytenhek23bdf862006-03-28 21:00:40 +0100610#
611# CPU supports 36-bit I/O
612#
613config IO_36
614 bool
615
Linus Torvalds1da177e2005-04-16 15:20:36 -0700616comment "Processor Features"
617
618config ARM_THUMB
619 bool "Support Thumb user binaries"
Eric Miao49cbe782009-01-20 14:15:18 +0800620 depends on CPU_ARM720T || CPU_ARM740T || CPU_ARM920T || CPU_ARM922T || CPU_ARM925T || CPU_ARM926T || CPU_ARM940T || CPU_ARM946E || CPU_ARM1020 || CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_V6 || CPU_V7 || CPU_FEROCEON
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621 default y
622 help
623 Say Y if you want to include kernel support for running user space
624 Thumb binaries.
625
626 The Thumb instruction set is a compressed form of the standard ARM
627 instruction set resulting in smaller binaries at the expense of
628 slightly less efficient code.
629
630 If you don't know what this all is, saying Y is a safe choice.
631
Catalin Marinasd7f864b2008-04-18 22:43:06 +0100632config ARM_THUMBEE
633 bool "Enable ThumbEE CPU extension"
634 depends on CPU_V7
635 help
636 Say Y here if you have a CPU with the ThumbEE extension and code to
637 make use of it. Say N for code that can run on CPUs without ThumbEE.
638
Leif Lindholm64d2dc32010-09-16 18:00:47 +0100639config SWP_EMULATE
640 bool "Emulate SWP/SWPB instructions"
641 depends on CPU_V7
642 select HAVE_PROC_CPU if PROC_FS
643 default y if SMP
644 help
645 ARMv6 architecture deprecates use of the SWP/SWPB instructions.
646 ARMv7 multiprocessing extensions introduce the ability to disable
647 these instructions, triggering an undefined instruction exception
648 when executed. Say Y here to enable software emulation of these
649 instructions for userspace (not kernel) using LDREX/STREX.
650 Also creates /proc/cpu/swp_emulation for statistics.
651
652 In some older versions of glibc [<=2.8] SWP is used during futex
653 trylock() operations with the assumption that the code will not
654 be preempted. This invalid assumption may be more likely to fail
655 with SWP emulation enabled, leading to deadlock of the user
656 application.
657
658 NOTE: when accessing uncached shared regions, LDREX/STREX rely
659 on an external transaction monitoring block called a global
660 monitor to maintain update atomicity. If your system does not
661 implement a global monitor, this option can cause programs that
662 perform SWP operations to uncached memory to deadlock.
663
664 If unsure, say Y.
665
Linus Torvalds1da177e2005-04-16 15:20:36 -0700666config CPU_BIG_ENDIAN
667 bool "Build big-endian kernel"
668 depends on ARCH_SUPPORTS_BIG_ENDIAN
669 help
670 Say Y if you plan on running a kernel in big-endian mode.
671 Note that your board must be properly built and your board
672 port must properly enable any big-endian related features
673 of your chipset/board/processor.
674
Catalin Marinas26584852009-05-30 14:00:18 +0100675config CPU_ENDIAN_BE8
676 bool
677 depends on CPU_BIG_ENDIAN
678 default CPU_V6 || CPU_V7
679 help
680 Support for the BE-8 (big-endian) mode on ARMv6 and ARMv7 processors.
681
682config CPU_ENDIAN_BE32
683 bool
684 depends on CPU_BIG_ENDIAN
685 default !CPU_ENDIAN_BE8
686 help
687 Support for the BE-32 (big-endian) mode on pre-ARMv6 processors.
688
Hyok S. Choi6afd6fa2006-09-28 21:46:34 +0900689config CPU_HIGH_VECTOR
Robert P. J. Day6340aa62007-02-17 19:05:24 +0100690 depends on !MMU && CPU_CP15 && !CPU_ARM740T
Hyok S. Choi6afd6fa2006-09-28 21:46:34 +0900691 bool "Select the High exception vector"
Hyok S. Choi6afd6fa2006-09-28 21:46:34 +0900692 help
693 Say Y here to select high exception vector(0xFFFF0000~).
694 The exception vector can be vary depending on the platform
695 design in nommu mode. If your platform needs to select
696 high exception vector, say Y.
697 Otherwise or if you are unsure, say N, and the low exception
698 vector (0x00000000~) will be used.
699
Linus Torvalds1da177e2005-04-16 15:20:36 -0700700config CPU_ICACHE_DISABLE
Hyok S. Choif12d0d72006-09-26 17:36:37 +0900701 bool "Disable I-Cache (I-bit)"
702 depends on CPU_CP15 && !(CPU_ARM610 || CPU_ARM710 || CPU_ARM720T || CPU_ARM740T || CPU_XSCALE || CPU_XSC3)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700703 help
704 Say Y here to disable the processor instruction cache. Unless
705 you have a reason not to or are unsure, say N.
706
707config CPU_DCACHE_DISABLE
Hyok S. Choif12d0d72006-09-26 17:36:37 +0900708 bool "Disable D-Cache (C-bit)"
709 depends on CPU_CP15
Linus Torvalds1da177e2005-04-16 15:20:36 -0700710 help
711 Say Y here to disable the processor data cache. Unless
712 you have a reason not to or are unsure, say N.
713
Hyok S. Choif37f46e2006-09-26 17:38:32 +0900714config CPU_DCACHE_SIZE
715 hex
716 depends on CPU_ARM740T || CPU_ARM946E
717 default 0x00001000 if CPU_ARM740T
718 default 0x00002000 # default size for ARM946E-S
719 help
720 Some cores are synthesizable to have various sized cache. For
721 ARM946E-S case, it can vary from 0KB to 1MB.
722 To support such cache operations, it is efficient to know the size
723 before compile time.
724 If your SoC is configured to have a different size, define the value
725 here with proper conditions.
726
Linus Torvalds1da177e2005-04-16 15:20:36 -0700727config CPU_DCACHE_WRITETHROUGH
728 bool "Force write through D-cache"
Paulius Zaleckas28853ac2009-03-25 13:10:01 +0200729 depends on (CPU_ARM740T || CPU_ARM920T || CPU_ARM922T || CPU_ARM925T || CPU_ARM926T || CPU_ARM940T || CPU_ARM946E || CPU_ARM1020 || CPU_FA526) && !CPU_DCACHE_DISABLE
Linus Torvalds1da177e2005-04-16 15:20:36 -0700730 default y if CPU_ARM925T
731 help
732 Say Y here to use the data cache in writethrough mode. Unless you
733 specifically require this or are unsure, say N.
734
735config CPU_CACHE_ROUND_ROBIN
736 bool "Round robin I and D cache replacement algorithm"
Hyok S. Choif37f46e2006-09-26 17:38:32 +0900737 depends on (CPU_ARM926T || CPU_ARM946E || CPU_ARM1020) && (!CPU_ICACHE_DISABLE || !CPU_DCACHE_DISABLE)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700738 help
739 Say Y here to use the predictable round-robin cache replacement
740 policy. Unless you specifically require this or are unsure, say N.
741
742config CPU_BPREDICT_DISABLE
743 bool "Disable branch prediction"
Russell King542f8692009-03-26 23:10:11 +0000744 depends on CPU_ARM1020 || CPU_V6 || CPU_MOHAWK || CPU_XSC3 || CPU_V7 || CPU_FA526
Linus Torvalds1da177e2005-04-16 15:20:36 -0700745 help
746 Say Y here to disable branch prediction. If unsure, say N.
Nicolas Pitre2d2669b2005-04-29 22:08:33 +0100747
Nicolas Pitre4b0e07a2005-05-05 23:24:45 +0100748config TLS_REG_EMUL
749 bool
Nicolas Pitre4b0e07a2005-05-05 23:24:45 +0100750 help
Nicolas Pitre70489c82005-05-12 19:27:12 +0100751 An SMP system using a pre-ARMv6 processor (there are apparently
752 a few prototypes like that in existence) and therefore access to
753 that required register must be emulated.
Nicolas Pitre4b0e07a2005-05-05 23:24:45 +0100754
Nicolas Pitredcef1f62005-06-08 19:00:47 +0100755config NEEDS_SYSCALL_FOR_CMPXCHG
756 bool
Nicolas Pitredcef1f62005-06-08 19:00:47 +0100757 help
758 SMP on a pre-ARMv6 processor? Well OK then.
759 Forget about fast user space cmpxchg support.
760 It is just not possible.
761
Catalin Marinasad642d92010-06-21 15:10:07 +0100762config DMA_CACHE_RWFO
763 bool "Enable read/write for ownership DMA cache maintenance"
764 depends on CPU_V6 && SMP
765 default y
766 help
767 The Snoop Control Unit on ARM11MPCore does not detect the
768 cache maintenance operations and the dma_{map,unmap}_area()
769 functions may leave stale cache entries on other CPUs. By
770 enabling this option, Read or Write For Ownership in the ARMv6
771 DMA cache maintenance functions is performed. These LDR/STR
772 instructions change the cache line state to shared or modified
773 so that the cache operation has the desired effect.
774
775 Note that the workaround is only valid on processors that do
776 not perform speculative loads into the D-cache. For such
777 processors, if cache maintenance operations are not broadcast
778 in hardware, other workarounds are needed (e.g. cache
779 maintenance broadcasting in software via FIQ).
780
Catalin Marinas953233d2007-02-05 14:48:08 +0100781config OUTER_CACHE
782 bool
Catalin Marinas382266a2007-02-05 14:48:19 +0100783
Catalin Marinas319f5512010-03-24 16:47:53 +0100784config OUTER_CACHE_SYNC
785 bool
786 help
787 The outer cache has a outer_cache_fns.sync function pointer
788 that can be used to drain the write buffer of the outer cache.
789
Lennert Buytenhek99c6dc12008-06-22 22:45:04 +0200790config CACHE_FEROCEON_L2
791 bool "Enable the Feroceon L2 cache controller"
Stanislav Samsonov794d15b2008-06-22 22:45:10 +0200792 depends on ARCH_KIRKWOOD || ARCH_MV78XX0
Lennert Buytenhek99c6dc12008-06-22 22:45:04 +0200793 default y
Catalin Marinas382266a2007-02-05 14:48:19 +0100794 select OUTER_CACHE
Lennert Buytenhek99c6dc12008-06-22 22:45:04 +0200795 help
796 This option enables the Feroceon L2 cache controller.
797
Ronen Shitrit4360bb42008-09-23 15:28:10 +0300798config CACHE_FEROCEON_L2_WRITETHROUGH
799 bool "Force Feroceon L2 cache write through"
800 depends on CACHE_FEROCEON_L2
Ronen Shitrit4360bb42008-09-23 15:28:10 +0300801 help
802 Say Y here to use the Feroceon L2 cache in writethrough mode.
803 Unless you specifically require this, say N for writeback mode.
804
Linus Torvalds1da177e2005-04-16 15:20:36 -0700805config CACHE_L2X0
Catalin Marinasba927952008-04-18 22:43:17 +0100806 bool "Enable the L2x0 outer cache controller"
Sascha Hauercb882142009-02-08 02:00:50 +0100807 depends on REALVIEW_EB_ARM11MP || MACH_REALVIEW_PB11MP || MACH_REALVIEW_PB1176 || \
Srinidhi Kasagar8e797a72010-04-03 19:10:45 +0100808 REALVIEW_EB_A9MP || ARCH_MX35 || ARCH_MX31 || MACH_REALVIEW_PBX || \
Russell King0b019a42010-08-10 23:17:52 +0100809 ARCH_NOMADIK || ARCH_OMAP4 || ARCH_S5PV310 || ARCH_TEGRA || \
810 ARCH_U8500 || ARCH_VEXPRESS_CA9X4
Catalin Marinasba927952008-04-18 22:43:17 +0100811 default y
Linus Torvalds1da177e2005-04-16 15:20:36 -0700812 select OUTER_CACHE
Catalin Marinas23107c52010-03-24 16:48:53 +0100813 select OUTER_CACHE_SYNC
Catalin Marinasba927952008-04-18 22:43:17 +0100814 help
815 This option enables the L2x0 PrimeCell.
Eric Miao905a09d2008-06-06 16:34:03 +0800816
Catalin Marinas9a6655e2010-08-31 13:05:22 +0100817config CACHE_PL310
818 bool
819 depends on CACHE_L2X0
820 default y if CPU_V7 && !CPU_V6
821 help
822 This option enables optimisations for the PL310 cache
823 controller.
824
Lennert Buytenhek573a6522009-11-24 19:33:52 +0200825config CACHE_TAUROS2
826 bool "Enable the Tauros2 L2 cache controller"
Haojian Zhuang66b19642010-04-28 10:59:45 -0400827 depends on (ARCH_DOVE || ARCH_MMP)
Lennert Buytenhek573a6522009-11-24 19:33:52 +0200828 default y
829 select OUTER_CACHE
830 help
831 This option enables the Tauros2 L2 cache controller (as
832 found on PJ1/PJ4).
833
Eric Miao905a09d2008-06-06 16:34:03 +0800834config CACHE_XSC3L2
835 bool "Enable the L2 cache on XScale3"
836 depends on CPU_XSC3
837 default y
838 select OUTER_CACHE
839 help
840 This option enables the L2 cache on XScale3.
Kirill A. Shutemov910a17e2009-09-15 10:23:53 +0100841
842config ARM_L1_CACHE_SHIFT
843 int
Kukjin Kimd6d502f2010-02-22 00:02:59 +0100844 default 6 if ARM_L1_CACHE_SHIFT_6
Kirill A. Shutemov910a17e2009-09-15 10:23:53 +0100845 default 5
Russell King47ab0de2010-05-15 11:02:43 +0100846
847config ARM_DMA_MEM_BUFFERABLE
848 bool "Use non-cacheable memory for DMA" if CPU_V6 && !CPU_V7
Catalin Marinas42c4daf2010-07-01 13:22:48 +0100849 depends on !(MACH_REALVIEW_PB1176 || REALVIEW_EB_ARM11MP || \
850 MACH_REALVIEW_PB11MP)
Russell King47ab0de2010-05-15 11:02:43 +0100851 default y if CPU_V6 || CPU_V7
852 help
853 Historically, the kernel has used strongly ordered mappings to
854 provide DMA coherent memory. With the advent of ARMv7, mapping
855 memory with differing types results in unpredictable behaviour,
856 so on these CPUs, this option is forced on.
857
858 Multiple mappings with differing attributes is also unpredictable
859 on ARMv6 CPUs, but since they do not have aggressive speculative
860 prefetch, no harm appears to occur.
861
862 However, drivers may be missing the necessary barriers for ARMv6,
863 and therefore turning this on may result in unpredictable driver
864 behaviour. Therefore, we offer this as an option.
865
866 You are recommended say 'Y' here and debug any affected drivers.
Russell Kingac1d4262010-05-17 17:24:04 +0100867
Catalin Marinase7c56502010-03-24 16:49:54 +0100868config ARCH_HAS_BARRIERS
869 bool
870 help
871 This option allows the use of custom mandatory barriers
872 included via the mach/barriers.h file.