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ARM: tegra: Remove dmas and dma-names for debug UART
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b2441318 1# SPDX-License-Identifier: GPL-2.0
1da177e4
LT
2config ARM
3 bool
4 default y
942fa985 5 select ARCH_32BIT_OFF_T
fed240d9 6 select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE if HAVE_KRETPROBES && FRAME_POINTER && !ARM_UNWIND
aef0f78e 7 select ARCH_HAS_BINFMT_FLAT
ee31bb05 8 select ARCH_HAS_CPU_FINALIZE_INIT if MMU
2792d84e 9 select ARCH_HAS_CURRENT_STACK_POINTER
c7780ab5 10 select ARCH_HAS_DEBUG_VIRTUAL if MMU
419e2f18 11 select ARCH_HAS_DMA_WRITE_COMBINE if !ARM_DMA_MEM_BUFFERABLE
2b68f6ca 12 select ARCH_HAS_ELF_RANDOMIZE
ee333554 13 select ARCH_HAS_FORTIFY_SOURCE
d8ae8a37 14 select ARCH_HAS_KEEPINITRD
75851720 15 select ARCH_HAS_KCOV
e69244d2 16 select ARCH_HAS_MEMBARRIER_SYNC_CORE
0ebeea8c 17 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
3010a5ea 18 select ARCH_HAS_PTE_SPECIAL if ARM_LPAE
347cb6af 19 select ARCH_HAS_SETUP_DMA_OPS
75851720 20 select ARCH_HAS_SET_MEMORY
9fbed16c 21 select ARCH_STACKWALK
ad21fc4f
LA
22 select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
23 select ARCH_HAS_STRICT_MODULE_RWX if MMU
ae626eb9
CH
24 select ARCH_HAS_SYNC_DMA_FOR_DEVICE
25 select ARCH_HAS_SYNC_DMA_FOR_CPU
dc2acded 26 select ARCH_HAS_TEARDOWN_DMA_OPS if MMU
3d06770e 27 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
9aaf9bb7 28 select ARCH_HAVE_NMI_SAFE_CMPXCHG if CPU_V7 || CPU_V7M || CPU_V6K
957e3fac 29 select ARCH_HAS_GCOV_PROFILE_ALL
5e545df3 30 select ARCH_KEEP_MEMBLOCK
d539fee9 31 select ARCH_HAS_UBSAN_SANITIZE_ALL
d7018848 32 select ARCH_MIGHT_HAVE_PC_PARPORT
ad21fc4f
LA
33 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
34 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT if CPU_V7
4badad35 35 select ARCH_SUPPORTS_ATOMIC_RMW
855f9a8e 36 select ARCH_SUPPORTS_HUGETLBFS if ARM_LPAE
017f161a 37 select ARCH_USE_BUILTIN_BSWAP
0cbad9c9 38 select ARCH_USE_CMPXCHG_LOCKREF
dce44566 39 select ARCH_USE_MEMTEST
dba79c3d 40 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
07431506 41 select ARCH_WANT_GENERAL_HUGETLB
b1b3f49c 42 select ARCH_WANT_IPC_PARSE_VERSION
59612b24 43 select ARCH_WANT_LD_ORPHAN_WARN
bdd15a28 44 select BINFMT_FLAT_ARGVP_ENVP_ON_STACK
10916706 45 select BUILDTIME_TABLE_SORT if MMU
6fd09c9a 46 select COMMON_CLK if !(ARCH_RPC || ARCH_FOOTBRIDGE)
171b3f0d 47 select CLONE_BACKWARDS
f00790aa 48 select CPU_PM if SUSPEND || CPU_IDLE
dce5c9e3 49 select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS
ff4c25f2 50 select DMA_DECLARE_COHERENT
31b089bb 51 select DMA_GLOBAL_POOL if !MMU
2f9237d4 52 select DMA_OPS
f5ff79fd 53 select DMA_NONCOHERENT_MMAP if MMU
b01aec9b
BP
54 select EDAC_SUPPORT
55 select EDAC_ATOMIC_SCRUB
36d0fd21 56 select GENERIC_ALLOCATOR
2ef7a295 57 select GENERIC_ARCH_TOPOLOGY if ARM_CPU_TOPOLOGY
f00790aa 58 select GENERIC_ATOMIC64 if CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI
b1b3f49c 59 select GENERIC_CLOCKEVENTS_BROADCAST if SMP
56afcd3d 60 select GENERIC_IRQ_IPI if SMP
ea2d9a96 61 select GENERIC_CPU_AUTOPROBE
2937367b 62 select GENERIC_EARLY_IOREMAP
171b3f0d 63 select GENERIC_IDLE_POLL_SETUP
234a0f20 64 select GENERIC_IRQ_MULTI_HANDLER
b1b3f49c
RK
65 select GENERIC_IRQ_PROBE
66 select GENERIC_IRQ_SHOW
7c07005e 67 select GENERIC_IRQ_SHOW_LEVEL
914ee966 68 select GENERIC_LIB_DEVMEM_IS_ALLOWED
b1b3f49c 69 select GENERIC_PCI_IOMAP
38ff87f7 70 select GENERIC_SCHED_CLOCK
b1b3f49c 71 select GENERIC_SMP_IDLE_THREAD
b1b3f49c 72 select HARDIRQS_SW_RESEND
fcbfe812 73 select HAS_IOPORT
f00790aa 74 select HAVE_ARCH_AUDITSYSCALL if AEABI && !OABI_COMPAT
0b7857db 75 select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
437682ee 76 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
75969686 77 select HAVE_ARCH_KFENCE if MMU && !XIP_KERNEL
437682ee 78 select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
42101571 79 select HAVE_ARCH_KASAN if MMU && !XIP_KERNEL
565cbaad 80 select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN
e0c25d95 81 select HAVE_ARCH_MMAP_RND_BITS if MMU
4f5b0c17 82 select HAVE_ARCH_PFN_VALID
282a181b 83 select HAVE_ARCH_SECCOMP
f00790aa 84 select HAVE_ARCH_SECCOMP_FILTER if AEABI && !OABI_COMPAT
08626a60 85 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
0693bf68 86 select HAVE_ARCH_TRACEHOOK
e8003bf6 87 select HAVE_ARCH_TRANSPARENT_HUGEPAGE if ARM_LPAE
b329f95d 88 select HAVE_ARM_SMCCC if CPU_V7
39c13c20 89 select HAVE_EBPF_JIT if !CPU_ENDIAN_BE32
24a9c541 90 select HAVE_CONTEXT_TRACKING_USER
b1b3f49c 91 select HAVE_C_RECORDMCOUNT
4ed308c4 92 select HAVE_BUILDTIME_MCOUNT_SORT
bc420c6c 93 select HAVE_DEBUG_KMEMLEAK if !XIP_KERNEL
b1b3f49c 94 select HAVE_DMA_CONTIGUOUS if MMU
f00790aa 95 select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
620176f3 96 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
dce5c9e3 97 select HAVE_EFFICIENT_UNALIGNED_ACCESS if (CPU_V6 || CPU_V6K || CPU_V7) && MMU
5f56a5df 98 select HAVE_EXIT_THREAD
67a929e0 99 select HAVE_FAST_GUP if ARM_LPAE
f00790aa 100 select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
aaa4dd1b 101 select HAVE_FUNCTION_ERROR_INJECTION
41918ec8 102 select HAVE_FUNCTION_GRAPH_TRACER
d6800ca7 103 select HAVE_FUNCTION_TRACER if !XIP_KERNEL
6b90bd4b 104 select HAVE_GCC_PLUGINS
f00790aa 105 select HAVE_HW_BREAKPOINT if PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7)
87c46b6c 106 select HAVE_IRQ_TIME_ACCOUNTING
e7db7b42 107 select HAVE_KERNEL_GZIP
f9b493ac 108 select HAVE_KERNEL_LZ4
6e8699f7 109 select HAVE_KERNEL_LZMA
b1b3f49c 110 select HAVE_KERNEL_LZO
a7f464f3 111 select HAVE_KERNEL_XZ
cb1293e2 112 select HAVE_KPROBES if !XIP_KERNEL && !CPU_ENDIAN_BE32 && !CPU_V7M
f00790aa 113 select HAVE_KRETPROBES if HAVE_KPROBES
7d485f64 114 select HAVE_MOD_ARCH_SPECIFIC
42a0bb3f 115 select HAVE_NMI
0dc016db 116 select HAVE_OPTPROBES if !THUMB2_KERNEL
47723de8 117 select HAVE_PCI if MMU
7ada189f 118 select HAVE_PERF_EVENTS
49863894
WD
119 select HAVE_PERF_REGS
120 select HAVE_PERF_USER_STACK_DUMP
ff2e6d72 121 select MMU_GATHER_RCU_TABLE_FREE if SMP && ARM_LPAE
e513f8bf 122 select HAVE_REGS_AND_STACK_ACCESS_API
9800b9dc 123 select HAVE_RSEQ
d148eac0 124 select HAVE_STACKPROTECTOR
b1b3f49c 125 select HAVE_SYSCALL_TRACEPOINTS
af1839eb 126 select HAVE_UID16
31c1fc81 127 select HAVE_VIRT_CPU_ACCOUNTING_GEN
5490e769 128 select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU
da0ec6f7 129 select IRQ_FORCED_THREADING
8b35ca3e 130 select LOCK_MM_AND_FIND_VMA
171b3f0d 131 select MODULES_USE_ELF_REL
f616ab59 132 select NEED_DMA_MAP_STATE
aa7d5f18 133 select OF_EARLY_FLATTREE if OF
171b3f0d
RK
134 select OLD_SIGACTION
135 select OLD_SIGSUSPEND3
6fd09c9a 136 select PCI_DOMAINS_GENERIC if PCI
20f1b79d 137 select PCI_SYSCALL if PCI
b1b3f49c
RK
138 select PERF_USE_VMALLOC
139 select RTC_LIB
6fd09c9a 140 select SPARSE_IRQ if !(ARCH_FOOTBRIDGE || ARCH_RPC)
b1b3f49c 141 select SYS_SUPPORTS_APM_EMULATION
9c46929e 142 select THREAD_INFO_IN_TASK
6fd09c9a 143 select TIMER_OF if OF
d6905849 144 select HAVE_ARCH_VMAP_STACK if MMU && ARM_HAS_GROUP_RELOCS
4aae683f 145 select TRACE_IRQFLAGS_SUPPORT if !CPU_V7M
6fd09c9a 146 select USE_OF if !(ARCH_FOOTBRIDGE || ARCH_RPC || ARCH_SA1100)
171b3f0d
RK
147 # Above selects are sorted alphabetically; please add new ones
148 # according to that. Thanks.
1da177e4
LT
149 help
150 The ARM series is a line of low-power-consumption RISC chip designs
f6c8965a 151 licensed by ARM Ltd and targeted at embedded applications and
1da177e4 152 handhelds such as the Compaq IPAQ. ARM-based PCs are no longer
f6c8965a 153 manufactured, but legacy ARM-based PC hardware remains popular in
1da177e4
LT
154 Europe. There is an ARM Linux project with a web page at
155 <http://www.arm.linux.org.uk/>.
156
d6905849
AB
157config ARM_HAS_GROUP_RELOCS
158 def_bool y
159 depends on !LD_IS_LLD || LLD_VERSION >= 140000
160 depends on !COMPILE_TEST
161 help
162 Whether or not to use R_ARM_ALU_PC_Gn or R_ARM_LDR_PC_Gn group
163 relocations, which have been around for a long time, but were not
164 supported in LLD until version 14. The combined range is -/+ 256 MiB,
165 which is usually sufficient, but not for allyesconfig, so we disable
166 this feature when doing compile testing.
167
4ce63fcd 168config ARM_DMA_USE_IOMMU
4ce63fcd 169 bool
b1b3f49c 170 select NEED_SG_DMA_LENGTH
4ce63fcd 171
60460abf
SWK
172if ARM_DMA_USE_IOMMU
173
174config ARM_DMA_IOMMU_ALIGNMENT
175 int "Maximum PAGE_SIZE order of alignment for DMA IOMMU buffers"
176 range 4 9
177 default 8
178 help
179 DMA mapping framework by default aligns all buffers to the smallest
180 PAGE_SIZE order which is greater than or equal to the requested buffer
181 size. This works well for buffers up to a few hundreds kilobytes, but
182 for larger buffers it just a waste of address space. Drivers which has
183 relatively small addressing window (like 64Mib) might run out of
184 virtual space with just a few allocations.
185
186 With this parameter you can specify the maximum PAGE_SIZE order for
187 DMA IOMMU buffers. Larger buffers will be aligned only to this
188 specified order. The order is expressed as a power of two multiplied
189 by the PAGE_SIZE.
190
191endif
192
75e7153a
RB
193config SYS_SUPPORTS_APM_EMULATION
194 bool
195
bc581770
LW
196config HAVE_TCM
197 bool
198 select GENERIC_ALLOCATOR
199
e119bfff
RK
200config HAVE_PROC_CPU
201 bool
202
ce816fa8 203config NO_IOPORT_MAP
5ea81769 204 bool
5ea81769 205
1da177e4
LT
206config SBUS
207 bool
208
f16fb1ec
RK
209config STACKTRACE_SUPPORT
210 bool
211 default y
212
213config LOCKDEP_SUPPORT
214 bool
215 default y
216
f0d1b0b3
DH
217config ARCH_HAS_ILOG2_U32
218 bool
f0d1b0b3
DH
219
220config ARCH_HAS_ILOG2_U64
221 bool
f0d1b0b3 222
4a1b5733
EV
223config ARCH_HAS_BANDGAP
224 bool
225
a5f4c561
SA
226config FIX_EARLYCON_MEM
227 def_bool y if MMU
228
b89c3b16
AM
229config GENERIC_HWEIGHT
230 bool
231 default y
232
1da177e4
LT
233config GENERIC_CALIBRATE_DELAY
234 bool
235 default y
236
a08b6b79
AV
237config ARCH_MAY_HAVE_PC_FDC
238 bool
239
c7edc9e3
DL
240config ARCH_SUPPORTS_UPROBES
241 def_bool y
242
1da177e4
LT
243config GENERIC_ISA_DMA
244 bool
245
1da177e4
LT
246config FIQ
247 bool
248
034d2f5a
AV
249config ARCH_MTD_XIP
250 bool
251
dc21af99 252config ARM_PATCH_PHYS_VIRT
c1becedc
RK
253 bool "Patch physical to virtual translations at runtime" if EMBEDDED
254 default y
5408445b 255 depends on MMU
dc21af99 256 help
111e9a5c
RK
257 Patch phys-to-virt and virt-to-phys translation functions at
258 boot and module load time according to the position of the
259 kernel in system memory.
dc21af99 260
111e9a5c 261 This can only be used with non-XIP MMU kernels where the base
9443076e 262 of physical memory is at a 2 MiB boundary.
dc21af99 263
c1becedc
RK
264 Only disable this option if you know that you do not require
265 this feature (eg, building a kernel for a single machine) and
266 you need to shrink the kernel to the minimal size.
dc21af99 267
c334bc15
RH
268config NEED_MACH_IO_H
269 bool
270 help
271 Select this when mach/io.h is required to provide special
272 definitions for this platform. The need for mach/io.h should
273 be avoided when possible.
274
0cdc8b92 275config NEED_MACH_MEMORY_H
1b9f95f8
NP
276 bool
277 help
0cdc8b92
NP
278 Select this when mach/memory.h is required to provide special
279 definitions for this platform. The need for mach/memory.h should
280 be avoided when possible.
dc21af99 281
1b9f95f8 282config PHYS_OFFSET
974c0724 283 hex "Physical address of main memory" if MMU
92481c7d 284 depends on !ARM_PATCH_PHYS_VIRT || !AUTO_ZRELADDR
974c0724 285 default DRAM_BASE if !MMU
06954b6a 286 default 0x00000000 if ARCH_FOOTBRIDGE
c6f54a9b 287 default 0x10000000 if ARCH_OMAP1 || ARCH_RPC
b91a69d1 288 default 0xa0000000 if ARCH_PXA
c6e77bb6
AB
289 default 0xc0000000 if ARCH_EP93XX || ARCH_SA1100
290 default 0
111e9a5c 291 help
1b9f95f8
NP
292 Please provide the physical address corresponding to the
293 location of main memory in your system.
cada3c08 294
87e040b6
SG
295config GENERIC_BUG
296 def_bool y
297 depends on BUG
298
1bcad26e
KS
299config PGTABLE_LEVELS
300 int
301 default 3 if ARM_LPAE
302 default 2
303
1da177e4
LT
304menu "System Type"
305
3c427975
HC
306config MMU
307 bool "MMU-based Paged Memory Management Support"
308 default y
309 help
310 Select if you want MMU-based virtualised addressing space
311 support by paged memory management. If unsure, say 'Y'.
312
2f618d5e
AB
313config ARM_SINGLE_ARMV7M
314 def_bool !MMU
315 select ARM_NVIC
2f618d5e
AB
316 select CPU_V7M
317 select NO_IOPORT_MAP
2f618d5e 318
e0c25d95
DC
319config ARCH_MMAP_RND_BITS_MIN
320 default 8
321
322config ARCH_MMAP_RND_BITS_MAX
323 default 14 if PAGE_OFFSET=0x40000000
324 default 15 if PAGE_OFFSET=0x80000000
325 default 16
326
387798b3 327config ARCH_MULTIPLATFORM
84fc8636
AB
328 bool "Require kernel to be portable to multiple machines" if EXPERT
329 depends on MMU && !(ARCH_FOOTBRIDGE || ARCH_RPC || ARCH_SA1100)
330 default y
1da177e4 331 help
84fc8636
AB
332 In general, all Arm machines can be supported in a single
333 kernel image, covering either Armv4/v5 or Armv6/v7.
1da177e4 334
84fc8636
AB
335 However, some configuration options require hardcoding machine
336 specific physical addresses or enable errata workarounds that may
337 break other machines.
1da177e4 338
84fc8636
AB
339 Selecting N here allows using those options, including
340 DEBUG_UNCOMPRESS, XIP_KERNEL and ZBOOT_ROM. If unsure, say Y.
1da177e4 341
6fd09c9a
AB
342menu "Platform selection"
343 depends on MMU
387798b3
RH
344
345comment "CPU Core family selection"
346
f8afae40 347config ARCH_MULTI_V4
6fd09c9a 348 bool "ARMv4 based platforms (FA526, StrongARM)"
f8afae40 349 depends on !ARCH_MULTI_V6_V7
5eb6e280
NC
350 # https://github.com/llvm/llvm-project/issues/50764
351 depends on !LD_IS_LLD || LLD_VERSION >= 160000
f8afae40 352 select ARCH_MULTI_V4_V5
6fd09c9a 353 select CPU_FA526 if !(CPU_SA110 || CPU_SA1100)
f8afae40 354
387798b3
RH
355config ARCH_MULTI_V4T
356 bool "ARMv4T based platforms (ARM720T, ARM920T, ...)"
387798b3 357 depends on !ARCH_MULTI_V6_V7
5eb6e280
NC
358 # https://github.com/llvm/llvm-project/issues/50764
359 depends on !LD_IS_LLD || LLD_VERSION >= 160000
b1b3f49c 360 select ARCH_MULTI_V4_V5
24e860fb
AB
361 select CPU_ARM920T if !(CPU_ARM7TDMI || CPU_ARM720T || \
362 CPU_ARM740T || CPU_ARM9TDMI || CPU_ARM922T || \
363 CPU_ARM925T || CPU_ARM940T)
387798b3
RH
364
365config ARCH_MULTI_V5
366 bool "ARMv5 based platforms (ARM926T, XSCALE, PJ1, ...)"
387798b3 367 depends on !ARCH_MULTI_V6_V7
b1b3f49c 368 select ARCH_MULTI_V4_V5
12567bbd 369 select CPU_ARM926T if !(CPU_ARM946E || CPU_ARM1020 || \
24e860fb
AB
370 CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || \
371 CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_FEROCEON)
387798b3
RH
372
373config ARCH_MULTI_V4_V5
374 bool
375
376config ARCH_MULTI_V6
8dda05cc 377 bool "ARMv6 based platforms (ARM11)"
387798b3 378 select ARCH_MULTI_V6_V7
42f4754a 379 select CPU_V6K
387798b3
RH
380
381config ARCH_MULTI_V7
8dda05cc 382 bool "ARMv7 based platforms (Cortex-A, PJ4, Scorpion, Krait)"
387798b3
RH
383 default y
384 select ARCH_MULTI_V6_V7
b1b3f49c 385 select CPU_V7
90bc8ac7 386 select HAVE_SMP
387798b3
RH
387
388config ARCH_MULTI_V6_V7
389 bool
9352b05b 390 select MIGHT_HAVE_CACHE_L2X0
387798b3
RH
391
392config ARCH_MULTI_CPU_AUTO
393 def_bool !(ARCH_MULTI_V4 || ARCH_MULTI_V4T || ARCH_MULTI_V6_V7)
394 select ARCH_MULTI_V5
395
396endmenu
397
05e2a3de 398config ARCH_VIRT
e3246542
MY
399 bool "Dummy Virtual Machine"
400 depends on ARCH_MULTI_V7
4b8b5f25 401 select ARM_AMBA
05e2a3de 402 select ARM_GIC
3ee80364 403 select ARM_GIC_V2M if PCI
0b28f1db 404 select ARM_GIC_V3
bb29cecb 405 select ARM_GIC_V3_ITS if PCI
05e2a3de 406 select ARM_PSCI
4b8b5f25 407 select HAVE_ARM_ARCH_TIMER
05e2a3de 408
2cf1c348
JC
409config ARCH_AIROHA
410 bool "Airoha SoC Support"
411 depends on ARCH_MULTI_V7
412 select ARM_AMBA
413 select ARM_GIC
414 select ARM_GIC_V3
415 select ARM_PSCI
416 select HAVE_ARM_ARCH_TIMER
2cf1c348
JC
417 help
418 Support for Airoha EN7523 SoCs
419
ccf50e23
RK
420#
421# This is sorted alphabetically by mach-* pathname. However, plat-*
422# Kconfigs may be included either alphabetically (according to the
423# plat- suffix) or along side the corresponding mach-* source.
424#
6bb8536c
AF
425source "arch/arm/mach-actions/Kconfig"
426
445d9b30
TZ
427source "arch/arm/mach-alpine/Kconfig"
428
590b460c
LP
429source "arch/arm/mach-artpec/Kconfig"
430
d9bfc86d
OR
431source "arch/arm/mach-asm9260/Kconfig"
432
a66c51f9
AB
433source "arch/arm/mach-aspeed/Kconfig"
434
95b8f20f
RK
435source "arch/arm/mach-at91/Kconfig"
436
1d22924e
AB
437source "arch/arm/mach-axxia/Kconfig"
438
8ac49e04
CD
439source "arch/arm/mach-bcm/Kconfig"
440
1c37fa10
SH
441source "arch/arm/mach-berlin/Kconfig"
442
1da177e4
LT
443source "arch/arm/mach-clps711x/Kconfig"
444
95b8f20f
RK
445source "arch/arm/mach-davinci/Kconfig"
446
df8d742e
BS
447source "arch/arm/mach-digicolor/Kconfig"
448
95b8f20f
RK
449source "arch/arm/mach-dove/Kconfig"
450
e7736d47
LB
451source "arch/arm/mach-ep93xx/Kconfig"
452
a66c51f9 453source "arch/arm/mach-exynos/Kconfig"
a66c51f9 454
1da177e4
LT
455source "arch/arm/mach-footbridge/Kconfig"
456
59d3a193
PZ
457source "arch/arm/mach-gemini/Kconfig"
458
387798b3
RH
459source "arch/arm/mach-highbank/Kconfig"
460
389ee0c2
HZ
461source "arch/arm/mach-hisi/Kconfig"
462
11d89440
NH
463source "arch/arm/mach-hpe/Kconfig"
464
a66c51f9
AB
465source "arch/arm/mach-imx/Kconfig"
466
1da177e4
LT
467source "arch/arm/mach-ixp4xx/Kconfig"
468
828989ad
SS
469source "arch/arm/mach-keystone/Kconfig"
470
75bf1bd7 471source "arch/arm/mach-lpc32xx/Kconfig"
95b8f20f 472
a66c51f9
AB
473source "arch/arm/mach-mediatek/Kconfig"
474
3b8f5030
CC
475source "arch/arm/mach-meson/Kconfig"
476
9fb29c73
ST
477source "arch/arm/mach-milbeaut/Kconfig"
478
a66c51f9 479source "arch/arm/mach-mmp/Kconfig"
17723fd3 480
a66c51f9 481source "arch/arm/mach-moxart/Kconfig"
8c2ed9bc 482
312b62b6
DP
483source "arch/arm/mach-mstar/Kconfig"
484
794d15b2
SS
485source "arch/arm/mach-mv78xx0/Kconfig"
486
a66c51f9 487source "arch/arm/mach-mvebu/Kconfig"
f682a218 488
1d3f33d5
SG
489source "arch/arm/mach-mxs/Kconfig"
490
95b8f20f 491source "arch/arm/mach-nomadik/Kconfig"
95b8f20f 492
7bffa14c
BH
493source "arch/arm/mach-npcm/Kconfig"
494
9851ca57
DT
495source "arch/arm/mach-nspire/Kconfig"
496
d48af15e 497source "arch/arm/mach-omap1/Kconfig"
1da177e4 498
1dbae815
TL
499source "arch/arm/mach-omap2/Kconfig"
500
9dd0b194 501source "arch/arm/mach-orion5x/Kconfig"
585cf175 502
95b8f20f 503source "arch/arm/mach-pxa/Kconfig"
585cf175 504
8fc1b0f8
KG
505source "arch/arm/mach-qcom/Kconfig"
506
78e3dbc1
AF
507source "arch/arm/mach-rda/Kconfig"
508
86aeee4d
AF
509source "arch/arm/mach-realtek/Kconfig"
510
6fd09c9a
AB
511source "arch/arm/mach-rpc/Kconfig"
512
d63dc051
HS
513source "arch/arm/mach-rockchip/Kconfig"
514
71b9114d 515source "arch/arm/mach-s3c/Kconfig"
a66c51f9
AB
516
517source "arch/arm/mach-s5pv210/Kconfig"
518
95b8f20f 519source "arch/arm/mach-sa1100/Kconfig"
edabd38e 520
a66c51f9
AB
521source "arch/arm/mach-shmobile/Kconfig"
522
387798b3
RH
523source "arch/arm/mach-socfpga/Kconfig"
524
a7ed099f 525source "arch/arm/mach-spear/Kconfig"
a21765a7 526
65ebcc11
SK
527source "arch/arm/mach-sti/Kconfig"
528
bcb84fb4
AT
529source "arch/arm/mach-stm32/Kconfig"
530
0aa94eea
QJ
531source "arch/arm/mach-sunplus/Kconfig"
532
3b52634f
MR
533source "arch/arm/mach-sunxi/Kconfig"
534
c5f80065
EG
535source "arch/arm/mach-tegra/Kconfig"
536
ba56a987
MY
537source "arch/arm/mach-uniphier/Kconfig"
538
95b8f20f 539source "arch/arm/mach-ux500/Kconfig"
1da177e4
LT
540
541source "arch/arm/mach-versatile/Kconfig"
542
6f35f9a9
TP
543source "arch/arm/mach-vt8500/Kconfig"
544
9a45eb69
JC
545source "arch/arm/mach-zynq/Kconfig"
546
499f1640 547# ARMv7-M architecture
499f1640
SA
548config ARCH_LPC18XX
549 bool "NXP LPC18xx/LPC43xx"
550 depends on ARM_SINGLE_ARMV7M
551 select ARCH_HAS_RESET_CONTROLLER
552 select ARM_AMBA
553 select CLKSRC_LPC32XX
554 select PINCTRL
555 help
556 Support for NXP's LPC18xx Cortex-M3 and LPC43xx Cortex-M4
557 high performance microcontrollers.
558
1847119d 559config ARCH_MPS2
17bd274e 560 bool "ARM MPS2 platform"
1847119d
VM
561 depends on ARM_SINGLE_ARMV7M
562 select ARM_AMBA
563 select CLKSRC_MPS2
564 help
565 Support for Cortex-M Prototyping System (or V2M-MPS2) which comes
566 with a range of available cores like Cortex-M3/M4/M7.
567
568 Please, note that depends which Application Note is used memory map
569 for the platform may vary, so adjustment of RAM base might be needed.
570
1da177e4
LT
571# Definitions to make life easier
572config ARCH_ACORN
573 bool
574
69b02f6a
LB
575config PLAT_ORION
576 bool
bfe45e0b 577 select CLKSRC_MMIO
dc7ad3b3 578 select GENERIC_IRQ_CHIP
278b45b0 579 select IRQ_DOMAIN
69b02f6a 580
abcda1dc
TP
581config PLAT_ORION_LEGACY
582 bool
583 select PLAT_ORION
584
f4b8b319
RK
585config PLAT_VERSATILE
586 bool
587
8636a1f9 588source "arch/arm/mm/Kconfig"
1da177e4 589
afe4b25e 590config IWMMXT
d93003e8
SH
591 bool "Enable iWMMXt support"
592 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B
593 default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 || CPU_PJ4B
afe4b25e
LB
594 help
595 Enable support for iWMMXt context switching at run time if
596 running on a CPU that supports it.
597
3b93e7b0
HC
598if !MMU
599source "arch/arm/Kconfig-nommu"
600endif
601
3e0a07f8
GC
602config PJ4B_ERRATA_4742
603 bool "PJ4B Errata 4742: IDLE Wake Up Commands can Cause the CPU Core to Cease Operation"
604 depends on CPU_PJ4B && MACH_ARMADA_370
605 default y
606 help
607 When coming out of either a Wait for Interrupt (WFI) or a Wait for
608 Event (WFE) IDLE states, a specific timing sensitivity exists between
609 the retiring WFI/WFE instructions and the newly issued subsequent
610 instructions. This sensitivity can result in a CPU hang scenario.
611 Workaround:
612 The software must insert either a Data Synchronization Barrier (DSB)
613 or Data Memory Barrier (DMB) command immediately after the WFI/WFE
614 instruction
615
f0c4b8d6
WD
616config ARM_ERRATA_326103
617 bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory"
618 depends on CPU_V6
619 help
620 Executing a SWP instruction to read-only memory does not set bit 11
621 of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to
622 treat the access as a read, preventing a COW from occurring and
623 causing the faulting task to livelock.
624
9cba3ccc
CM
625config ARM_ERRATA_411920
626 bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
e399b1a4 627 depends on CPU_V6 || CPU_V6K
9cba3ccc
CM
628 help
629 Invalidation of the Instruction Cache operation can
630 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
631 It does not affect the MPCore. This option enables the ARM Ltd.
632 recommended workaround.
633
7ce236fc
CM
634config ARM_ERRATA_430973
635 bool "ARM errata: Stale prediction on replaced interworking branch"
636 depends on CPU_V7
637 help
638 This option enables the workaround for the 430973 Cortex-A8
79403cda 639 r1p* erratum. If a code sequence containing an ARM/Thumb
7ce236fc
CM
640 interworking branch is replaced with another code sequence at the
641 same virtual address, whether due to self-modifying code or virtual
642 to physical address re-mapping, Cortex-A8 does not recover from the
643 stale interworking branch prediction. This results in Cortex-A8
644 executing the new code sequence in the incorrect ARM or Thumb state.
645 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
646 and also flushes the branch target cache at every context switch.
647 Note that setting specific bits in the ACTLR register may not be
648 available in non-secure mode.
649
855c551f
CM
650config ARM_ERRATA_458693
651 bool "ARM errata: Processor deadlock when a false hazard is created"
652 depends on CPU_V7
62e4d357 653 depends on !ARCH_MULTIPLATFORM
855c551f
CM
654 help
655 This option enables the workaround for the 458693 Cortex-A8 (r2p0)
656 erratum. For very specific sequences of memory operations, it is
657 possible for a hazard condition intended for a cache line to instead
658 be incorrectly associated with a different cache line. This false
659 hazard might then cause a processor deadlock. The workaround enables
660 the L1 caching of the NEON accesses and disables the PLD instruction
661 in the ACTLR register. Note that setting specific bits in the ACTLR
368ccecd
SR
662 register may not be available in non-secure mode and thus is not
663 available on a multiplatform kernel. This should be applied by the
664 bootloader instead.
855c551f 665
0516e464
CM
666config ARM_ERRATA_460075
667 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
668 depends on CPU_V7
62e4d357 669 depends on !ARCH_MULTIPLATFORM
0516e464
CM
670 help
671 This option enables the workaround for the 460075 Cortex-A8 (r2p0)
672 erratum. Any asynchronous access to the L2 cache may encounter a
673 situation in which recent store transactions to the L2 cache are lost
674 and overwritten with stale memory contents from external memory. The
675 workaround disables the write-allocate mode for the L2 cache via the
676 ACTLR register. Note that setting specific bits in the ACTLR register
368ccecd
SR
677 may not be available in non-secure mode and thus is not available on
678 a multiplatform kernel. This should be applied by the bootloader
679 instead.
0516e464 680
9f05027c
WD
681config ARM_ERRATA_742230
682 bool "ARM errata: DMB operation may be faulty"
683 depends on CPU_V7 && SMP
62e4d357 684 depends on !ARCH_MULTIPLATFORM
9f05027c
WD
685 help
686 This option enables the workaround for the 742230 Cortex-A9
687 (r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction
688 between two write operations may not ensure the correct visibility
689 ordering of the two writes. This workaround sets a specific bit in
690 the diagnostic register of the Cortex-A9 which causes the DMB
691 instruction to behave as a DSB, ensuring the correct behaviour of
368ccecd
SR
692 the two writes. Note that setting specific bits in the diagnostics
693 register may not be available in non-secure mode and thus is not
694 available on a multiplatform kernel. This should be applied by the
695 bootloader instead.
9f05027c 696
a672e99b
WD
697config ARM_ERRATA_742231
698 bool "ARM errata: Incorrect hazard handling in the SCU may lead to data corruption"
699 depends on CPU_V7 && SMP
62e4d357 700 depends on !ARCH_MULTIPLATFORM
a672e99b
WD
701 help
702 This option enables the workaround for the 742231 Cortex-A9
703 (r2p0..r2p2) erratum. Under certain conditions, specific to the
704 Cortex-A9 MPCore micro-architecture, two CPUs working in SMP mode,
705 accessing some data located in the same cache line, may get corrupted
706 data due to bad handling of the address hazard when the line gets
707 replaced from one of the CPUs at the same time as another CPU is
708 accessing it. This workaround sets specific bits in the diagnostic
709 register of the Cortex-A9 which reduces the linefill issuing
368ccecd
SR
710 capabilities of the processor. Note that setting specific bits in the
711 diagnostics register may not be available in non-secure mode and thus
712 is not available on a multiplatform kernel. This should be applied by
713 the bootloader instead.
a672e99b 714
69155794
JM
715config ARM_ERRATA_643719
716 bool "ARM errata: LoUIS bit field in CLIDR register is incorrect"
717 depends on CPU_V7 && SMP
e5a5de44 718 default y
69155794
JM
719 help
720 This option enables the workaround for the 643719 Cortex-A9 (prior to
721 r1p0) erratum. On affected cores the LoUIS bit field of the CLIDR
722 register returns zero when it should return one. The workaround
723 corrects this value, ensuring cache maintenance operations which use
724 it behave as intended and avoiding data corruption.
725
cdf357f1
WD
726config ARM_ERRATA_720789
727 bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID"
e66dc745 728 depends on CPU_V7
cdf357f1
WD
729 help
730 This option enables the workaround for the 720789 Cortex-A9 (prior to
731 r2p0) erratum. A faulty ASID can be sent to the other CPUs for the
732 broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS.
733 As a consequence of this erratum, some TLB entries which should be
734 invalidated are not, resulting in an incoherency in the system page
735 tables. The workaround changes the TLB flushing routines to invalidate
736 entries regardless of the ASID.
475d92fc
WD
737
738config ARM_ERRATA_743622
739 bool "ARM errata: Faulty hazard checking in the Store Buffer may lead to data corruption"
740 depends on CPU_V7
62e4d357 741 depends on !ARCH_MULTIPLATFORM
475d92fc
WD
742 help
743 This option enables the workaround for the 743622 Cortex-A9
efbc74ac 744 (r2p*) erratum. Under very rare conditions, a faulty
475d92fc
WD
745 optimisation in the Cortex-A9 Store Buffer may lead to data
746 corruption. This workaround sets a specific bit in the diagnostic
747 register of the Cortex-A9 which disables the Store Buffer
748 optimisation, preventing the defect from occurring. This has no
749 visible impact on the overall performance or power consumption of the
368ccecd
SR
750 processor. Note that setting specific bits in the diagnostics register
751 may not be available in non-secure mode and thus is not available on a
752 multiplatform kernel. This should be applied by the bootloader instead.
475d92fc 753
9a27c27c
WD
754config ARM_ERRATA_751472
755 bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation"
ba90c516 756 depends on CPU_V7
62e4d357 757 depends on !ARCH_MULTIPLATFORM
9a27c27c
WD
758 help
759 This option enables the workaround for the 751472 Cortex-A9 (prior
760 to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the
761 completion of a following broadcasted operation if the second
762 operation is received by a CPU before the ICIALLUIS has completed,
763 potentially leading to corrupted entries in the cache or TLB.
368ccecd
SR
764 Note that setting specific bits in the diagnostics register may
765 not be available in non-secure mode and thus is not available on
766 a multiplatform kernel. This should be applied by the bootloader
767 instead.
9a27c27c 768
fcbdc5fe
WD
769config ARM_ERRATA_754322
770 bool "ARM errata: possible faulty MMU translations following an ASID switch"
771 depends on CPU_V7
772 help
773 This option enables the workaround for the 754322 Cortex-A9 (r2p*,
774 r3p*) erratum. A speculative memory access may cause a page table walk
775 which starts prior to an ASID switch but completes afterwards. This
776 can populate the micro-TLB with a stale entry which may be hit with
777 the new ASID. This workaround places two dsb instructions in the mm
778 switching code so that no page table walks can cross the ASID switch.
779
5dab26af
WD
780config ARM_ERRATA_754327
781 bool "ARM errata: no automatic Store Buffer drain"
782 depends on CPU_V7 && SMP
783 help
784 This option enables the workaround for the 754327 Cortex-A9 (prior to
785 r2p0) erratum. The Store Buffer does not have any automatic draining
786 mechanism and therefore a livelock may occur if an external agent
787 continuously polls a memory location waiting to observe an update.
788 This workaround defines cpu_relax() as smp_mb(), preventing correctly
789 written polling loops from denying visibility of updates to memory.
790
145e10e1
CM
791config ARM_ERRATA_364296
792 bool "ARM errata: Possible cache data corruption with hit-under-miss enabled"
fd832478 793 depends on CPU_V6
145e10e1
CM
794 help
795 This options enables the workaround for the 364296 ARM1136
796 r0p2 erratum (possible cache data corruption with
797 hit-under-miss enabled). It sets the undocumented bit 31 in
798 the auxiliary control register and the FI bit in the control
799 register, thus disabling hit-under-miss without putting the
800 processor into full low interrupt latency mode. ARM11MPCore
801 is not affected.
802
f630c1bd
WD
803config ARM_ERRATA_764369
804 bool "ARM errata: Data cache line maintenance operation by MVA may not succeed"
805 depends on CPU_V7 && SMP
806 help
807 This option enables the workaround for erratum 764369
808 affecting Cortex-A9 MPCore with two or more processors (all
809 current revisions). Under certain timing circumstances, a data
810 cache line maintenance operation by MVA targeting an Inner
811 Shareable memory region may fail to proceed up to either the
812 Point of Coherency or to the Point of Unification of the
813 system. This workaround adds a DSB instruction before the
814 relevant cache maintenance functions and sets a specific bit
815 in the diagnostic control register of the SCU.
816
8294fec1
NH
817config ARM_ERRATA_764319
818 bool "ARM errata: Read to DBGPRSR and DBGOSLSR may generate Undefined instruction"
819 depends on CPU_V7
820 help
821 This option enables the workaround for the 764319 Cortex A-9 erratum.
822 CP14 read accesses to the DBGPRSR and DBGOSLSR registers generate an
823 unexpected Undefined Instruction exception when the DBGSWENABLE
824 external pin is set to 0, even when the CP14 accesses are performed
825 from a privileged mode. This work around catches the exception in a
826 way the kernel does not stop execution.
827
7253b85c
SH
828config ARM_ERRATA_775420
829 bool "ARM errata: A data cache maintenance operation which aborts, might lead to deadlock"
830 depends on CPU_V7
831 help
832 This option enables the workaround for the 775420 Cortex-A9 (r2p2,
cb73737e 833 r2p6,r2p8,r2p10,r3p0) erratum. In case a data cache maintenance
7253b85c
SH
834 operation aborts with MMU exception, it might cause the processor
835 to deadlock. This workaround puts DSB before executing ISB if
836 an abort may occur on cache maintenance.
837
93dc6887
CM
838config ARM_ERRATA_798181
839 bool "ARM errata: TLBI/DSB failure on Cortex-A15"
840 depends on CPU_V7 && SMP
841 help
842 On Cortex-A15 (r0p0..r3p2) the TLBI*IS/DSB operations are not
843 adequately shooting down all use of the old entries. This
844 option enables the Linux kernel workaround for this erratum
845 which sends an IPI to the CPUs that are running the same ASID
846 as the one being invalidated.
847
84b6504f
WD
848config ARM_ERRATA_773022
849 bool "ARM errata: incorrect instructions may be executed from loop buffer"
850 depends on CPU_V7
851 help
852 This option enables the workaround for the 773022 Cortex-A15
853 (up to r0p4) erratum. In certain rare sequences of code, the
854 loop buffer may deliver incorrect instructions. This
855 workaround disables the loop buffer to avoid the erratum.
856
62c0f4a5
DA
857config ARM_ERRATA_818325_852422
858 bool "ARM errata: A12: some seqs of opposed cond code instrs => deadlock or corruption"
859 depends on CPU_V7
860 help
861 This option enables the workaround for:
862 - Cortex-A12 818325: Execution of an UNPREDICTABLE STR or STM
863 instruction might deadlock. Fixed in r0p1.
864 - Cortex-A12 852422: Execution of a sequence of instructions might
865 lead to either a data corruption or a CPU deadlock. Not fixed in
866 any Cortex-A12 cores yet.
867 This workaround for all both errata involves setting bit[12] of the
868 Feature Register. This bit disables an optimisation applied to a
869 sequence of 2 instructions that use opposing condition codes.
870
416bcf21
DA
871config ARM_ERRATA_821420
872 bool "ARM errata: A12: sequence of VMOV to core registers might lead to a dead lock"
873 depends on CPU_V7
874 help
875 This option enables the workaround for the 821420 Cortex-A12
876 (all revs) erratum. In very rare timing conditions, a sequence
877 of VMOV to Core registers instructions, for which the second
878 one is in the shadow of a branch or abort, can lead to a
879 deadlock when the VMOV instructions are issued out-of-order.
880
9f6f9354
DA
881config ARM_ERRATA_825619
882 bool "ARM errata: A12: DMB NSHST/ISHST mixed ... might cause deadlock"
883 depends on CPU_V7
884 help
885 This option enables the workaround for the 825619 Cortex-A12
886 (all revs) erratum. Within rare timing constraints, executing a
887 DMB NSHST or DMB ISHST instruction followed by a mix of Cacheable
888 and Device/Strongly-Ordered loads and stores might cause deadlock
889
304009a1
DA
890config ARM_ERRATA_857271
891 bool "ARM errata: A12: CPU might deadlock under some very rare internal conditions"
892 depends on CPU_V7
893 help
894 This option enables the workaround for the 857271 Cortex-A12
895 (all revs) erratum. Under very rare timing conditions, the CPU might
896 hang. The workaround is expected to have a < 1% performance impact.
897
9f6f9354
DA
898config ARM_ERRATA_852421
899 bool "ARM errata: A17: DMB ST might fail to create order between stores"
900 depends on CPU_V7
901 help
902 This option enables the workaround for the 852421 Cortex-A17
903 (r1p0, r1p1, r1p2) erratum. Under very rare timing conditions,
904 execution of a DMB ST instruction might fail to properly order
905 stores from GroupA and stores from GroupB.
906
62c0f4a5
DA
907config ARM_ERRATA_852423
908 bool "ARM errata: A17: some seqs of opposed cond code instrs => deadlock or corruption"
909 depends on CPU_V7
910 help
911 This option enables the workaround for:
912 - Cortex-A17 852423: Execution of a sequence of instructions might
913 lead to either a data corruption or a CPU deadlock. Not fixed in
914 any Cortex-A17 cores yet.
915 This is identical to Cortex-A12 erratum 852422. It is a separate
916 config option from the A12 erratum due to the way errata are checked
917 for and handled.
918
304009a1
DA
919config ARM_ERRATA_857272
920 bool "ARM errata: A17: CPU might deadlock under some very rare internal conditions"
921 depends on CPU_V7
922 help
923 This option enables the workaround for the 857272 Cortex-A17 erratum.
924 This erratum is not known to be fixed in any A17 revision.
925 This is identical to Cortex-A12 erratum 857271. It is a separate
926 config option from the A12 erratum due to the way errata are checked
927 for and handled.
928
1da177e4
LT
929endmenu
930
931source "arch/arm/common/Kconfig"
932
1da177e4
LT
933menu "Bus support"
934
1da177e4
LT
935config ISA
936 bool
1da177e4
LT
937 help
938 Find out whether you have ISA slots on your motherboard. ISA is the
939 name of a bus system, i.e. the way the CPU talks to the other stuff
940 inside your box. Other bus systems are PCI, EISA, MicroChannel
941 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
942 newer boards don't support it. If you have ISA, say Y, otherwise N.
943
065909b9 944# Select ISA DMA interface
5cae841b
AV
945config ISA_DMA_API
946 bool
5cae841b 947
779eb41c
BG
948config ARM_ERRATA_814220
949 bool "ARM errata: Cache maintenance by set/way operations can execute out of order"
950 depends on CPU_V7
951 help
952 The v7 ARM states that all cache and branch predictor maintenance
953 operations that do not specify an address execute, relative to
954 each other, in program order.
955 However, because of this erratum, an L2 set/way cache maintenance
956 operation can overtake an L1 set/way cache maintenance operation.
957 This ERRATA only affected the Cortex-A7 and present in r0p2, r0p3,
958 r0p4, r0p5.
959
1da177e4
LT
960endmenu
961
962menu "Kernel Features"
963
3b55658a
DM
964config HAVE_SMP
965 bool
966 help
967 This option should be selected by machines which have an SMP-
968 capable CPU.
969
970 The only effect of this option is to make the SMP-related
971 options available to the user for configuration.
972
1da177e4 973config SMP
bb2d8130 974 bool "Symmetric Multi-Processing"
fbb4ddac 975 depends on CPU_V6K || CPU_V7
3b55658a 976 depends on HAVE_SMP
801bb21c 977 depends on MMU || ARM_MPU
0361748f 978 select IRQ_WORK
1da177e4
LT
979 help
980 This enables support for systems with more than one CPU. If you have
4a474157
RG
981 a system with only one CPU, say N. If you have a system with more
982 than one CPU, say Y.
1da177e4 983
4a474157 984 If you say N here, the kernel will run on uni- and multiprocessor
1da177e4 985 machines, but will use only one CPU of a multiprocessor machine. If
4a474157
RG
986 you say Y here, the kernel will run on many, but not all,
987 uniprocessor machines. On a uniprocessor machine, the kernel
988 will run faster if you say N here.
1da177e4 989
ff61f079 990 See also <file:Documentation/arch/x86/i386/IO-APIC.rst>,
4f4cfa6c 991 <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at
50a23e6e 992 <http://tldp.org/HOWTO/SMP-HOWTO.html>.
1da177e4
LT
993
994 If you don't know what to do here, say N.
995
f00ec48f 996config SMP_ON_UP
5744ff43 997 bool "Allow booting SMP kernel on uniprocessor systems"
5408445b 998 depends on SMP && MMU
f00ec48f
RK
999 default y
1000 help
1001 SMP kernels contain instructions which fail on non-SMP processors.
1002 Enabling this option allows the kernel to modify itself to make
1003 these instructions safe. Disabling it allows about 1K of space
1004 savings.
1005
1006 If you don't know what to do here, say Y.
1007
50596b75
AB
1008
1009config CURRENT_POINTER_IN_TPIDRURO
1010 def_bool y
b87cf911 1011 depends on CPU_32v6K && !CPU_V6
50596b75 1012
d4664b6c
AB
1013config IRQSTACKS
1014 def_bool y
9974f857
AB
1015 select HAVE_IRQ_EXIT_ON_IRQ_STACK
1016 select HAVE_SOFTIRQ_ON_OWN_STACK
50596b75 1017
c9018aab
VG
1018config ARM_CPU_TOPOLOGY
1019 bool "Support cpu topology definition"
1020 depends on SMP && CPU_V7
1021 default y
1022 help
1023 Support ARM cpu topology definition. The MPIDR register defines
1024 affinity between processors which is then used to describe the cpu
1025 topology of an ARM System.
1026
1027config SCHED_MC
1028 bool "Multi-core scheduler support"
1029 depends on ARM_CPU_TOPOLOGY
1030 help
1031 Multi-core scheduler support improves the CPU scheduler's decision
1032 making when dealing with multi-core CPU chips at a cost of slightly
1033 increased overhead in some places. If unsure say N here.
1034
1035config SCHED_SMT
1036 bool "SMT scheduler support"
1037 depends on ARM_CPU_TOPOLOGY
1038 help
1039 Improves the CPU scheduler's decision making when dealing with
1040 MultiThreading at a cost of slightly increased overhead in some
1041 places. If unsure say N here.
1042
a8cbcd92
RK
1043config HAVE_ARM_SCU
1044 bool
a8cbcd92 1045 help
8f433ec4 1046 This option enables support for the ARM snoop control unit
a8cbcd92 1047
8a4da6e3 1048config HAVE_ARM_ARCH_TIMER
022c03a2
MZ
1049 bool "Architected timer support"
1050 depends on CPU_V7
8a4da6e3 1051 select ARM_ARCH_TIMER
022c03a2
MZ
1052 help
1053 This option enables support for the ARM architected timer
1054
f32f4ce2
RK
1055config HAVE_ARM_TWD
1056 bool
f32f4ce2
RK
1057 help
1058 This options enables support for the ARM timer and watchdog unit
1059
e8db288e
NP
1060config MCPM
1061 bool "Multi-Cluster Power Management"
1062 depends on CPU_V7 && SMP
1063 help
1064 This option provides the common power management infrastructure
1065 for (multi-)cluster based systems, such as big.LITTLE based
1066 systems.
1067
ebf4a5c5
HZ
1068config MCPM_QUAD_CLUSTER
1069 bool
1070 depends on MCPM
1071 help
1072 To avoid wasting resources unnecessarily, MCPM only supports up
1073 to 2 clusters by default.
1074 Platforms with 3 or 4 clusters that use MCPM must select this
1075 option to allow the additional clusters to be managed.
1076
1c33be57
NP
1077config BIG_LITTLE
1078 bool "big.LITTLE support (Experimental)"
1079 depends on CPU_V7 && SMP
1080 select MCPM
1081 help
1082 This option enables support selections for the big.LITTLE
1083 system architecture.
1084
1085config BL_SWITCHER
1086 bool "big.LITTLE switcher support"
6c044fec 1087 depends on BIG_LITTLE && MCPM && HOTPLUG_CPU && ARM_GIC
51aaf81f 1088 select CPU_PM
1c33be57
NP
1089 help
1090 The big.LITTLE "switcher" provides the core functionality to
1091 transparently handle transition between a cluster of A15's
1092 and a cluster of A7's in a big.LITTLE system.
1093
b22537c6
NP
1094config BL_SWITCHER_DUMMY_IF
1095 tristate "Simple big.LITTLE switcher user interface"
1096 depends on BL_SWITCHER && DEBUG_KERNEL
1097 help
1098 This is a simple and dummy char dev interface to control
1099 the big.LITTLE switcher core code. It is meant for
1100 debugging purposes only.
1101
8d5796d2
LB
1102choice
1103 prompt "Memory split"
006fa259 1104 depends on MMU
8d5796d2
LB
1105 default VMSPLIT_3G
1106 help
1107 Select the desired split between kernel and user memory.
1108
1109 If you are not absolutely sure what you are doing, leave this
1110 option alone!
1111
1112 config VMSPLIT_3G
1113 bool "3G/1G user/kernel split"
63ce446c 1114 config VMSPLIT_3G_OPT
bbeedfda 1115 depends on !ARM_LPAE
63ce446c 1116 bool "3G/1G user/kernel split (for full 1G low memory)"
8d5796d2
LB
1117 config VMSPLIT_2G
1118 bool "2G/2G user/kernel split"
1119 config VMSPLIT_1G
1120 bool "1G/3G user/kernel split"
1121endchoice
1122
1123config PAGE_OFFSET
1124 hex
006fa259 1125 default PHYS_OFFSET if !MMU
8d5796d2
LB
1126 default 0x40000000 if VMSPLIT_1G
1127 default 0x80000000 if VMSPLIT_2G
63ce446c 1128 default 0xB0000000 if VMSPLIT_3G_OPT
8d5796d2
LB
1129 default 0xC0000000
1130
c12366ba
LW
1131config KASAN_SHADOW_OFFSET
1132 hex
1133 depends on KASAN
1134 default 0x1f000000 if PAGE_OFFSET=0x40000000
1135 default 0x5f000000 if PAGE_OFFSET=0x80000000
1136 default 0x9f000000 if PAGE_OFFSET=0xC0000000
1137 default 0x8f000000 if PAGE_OFFSET=0xB0000000
1138 default 0xffffffff
1139
1da177e4
LT
1140config NR_CPUS
1141 int "Maximum number of CPUs (2-32)"
d624833f
AB
1142 range 2 16 if DEBUG_KMAP_LOCAL
1143 range 2 32 if !DEBUG_KMAP_LOCAL
1da177e4
LT
1144 depends on SMP
1145 default "4"
d624833f
AB
1146 help
1147 The maximum number of CPUs that the kernel can support.
1148 Up to 32 CPUs can be supported, or up to 16 if kmap_local()
1149 debugging is enabled, which uses half of the per-CPU fixmap
1150 slots as guard regions.
1da177e4 1151
a054a811 1152config HOTPLUG_CPU
00b7dede 1153 bool "Support for hot-pluggable CPUs"
40b31360 1154 depends on SMP
1b5ba350 1155 select GENERIC_IRQ_MIGRATION
a054a811
RK
1156 help
1157 Say Y here to experiment with turning CPUs off and on. CPUs
1158 can be controlled through /sys/devices/system/cpu.
1159
2bdd424f
WD
1160config ARM_PSCI
1161 bool "Support for the ARM Power State Coordination Interface (PSCI)"
e679660d 1162 depends on HAVE_ARM_SMCCC
be120397 1163 select ARM_PSCI_FW
2bdd424f
WD
1164 help
1165 Say Y here if you want Linux to communicate with system firmware
1166 implementing the PSCI specification for CPU-centric power
1167 management operations described in ARM document number ARM DEN
1168 0022A ("Power State Coordination Interface System Software on
1169 ARM processors").
1170
c9218b16 1171config HZ_FIXED
f8065813 1172 int
1164f672 1173 default 128 if SOC_AT91RM9200
47d84682 1174 default 0
c9218b16
RK
1175
1176choice
47d84682 1177 depends on HZ_FIXED = 0
c9218b16
RK
1178 prompt "Timer frequency"
1179
1180config HZ_100
1181 bool "100 Hz"
1182
1183config HZ_200
1184 bool "200 Hz"
1185
1186config HZ_250
1187 bool "250 Hz"
1188
1189config HZ_300
1190 bool "300 Hz"
1191
1192config HZ_500
1193 bool "500 Hz"
1194
1195config HZ_1000
1196 bool "1000 Hz"
1197
1198endchoice
1199
1200config HZ
1201 int
47d84682 1202 default HZ_FIXED if HZ_FIXED != 0
c9218b16
RK
1203 default 100 if HZ_100
1204 default 200 if HZ_200
1205 default 250 if HZ_250
1206 default 300 if HZ_300
1207 default 500 if HZ_500
1208 default 1000
1209
1210config SCHED_HRTICK
1211 def_bool HIGH_RES_TIMERS
f8065813 1212
16c79651 1213config THUMB2_KERNEL
bc7dea00 1214 bool "Compile the kernel in Thumb-2 mode" if !CPU_THUMBONLY
4477ca45 1215 depends on (CPU_V7 || CPU_V7M) && !CPU_V6 && !CPU_V6K
bc7dea00 1216 default y if CPU_THUMBONLY
89bace65 1217 select ARM_UNWIND
16c79651
CM
1218 help
1219 By enabling this option, the kernel will be compiled in
75fea300 1220 Thumb-2 mode.
16c79651
CM
1221
1222 If unsure, say N.
1223
42f25bdd
NP
1224config ARM_PATCH_IDIV
1225 bool "Runtime patch udiv/sdiv instructions into __aeabi_{u}idiv()"
5408445b 1226 depends on CPU_32v7
42f25bdd
NP
1227 default y
1228 help
1229 The ARM compiler inserts calls to __aeabi_idiv() and
1230 __aeabi_uidiv() when it needs to perform division on signed
1231 and unsigned integers. Some v7 CPUs have support for the sdiv
1232 and udiv instructions that can be used to implement those
1233 functions.
1234
1235 Enabling this option allows the kernel to modify itself to
1236 replace the first two instructions of these library functions
1237 with the sdiv or udiv plus "bx lr" instructions when the CPU
1238 it is running on supports them. Typically this will be faster
1239 and less power intensive than running the original library
1240 code to do integer division.
1241
704bdda0 1242config AEABI
a05b9608
ND
1243 bool "Use the ARM EABI to compile the kernel" if !CPU_V7 && \
1244 !CPU_V7M && !CPU_V6 && !CPU_V6K && !CC_IS_CLANG
1245 default CPU_V7 || CPU_V7M || CPU_V6 || CPU_V6K || CC_IS_CLANG
704bdda0
NP
1246 help
1247 This option allows for the kernel to be compiled using the latest
1248 ARM ABI (aka EABI). This is only useful if you are using a user
1249 space environment that is also compiled with EABI.
1250
1251 Since there are major incompatibilities between the legacy ABI and
1252 EABI, especially with regard to structure member alignment, this
1253 option also changes the kernel syscall calling convention to
1254 disambiguate both ABIs and allow for backward compatibility support
1255 (selected with CONFIG_OABI_COMPAT).
1256
1257 To use this you need GCC version 4.0.0 or later.
1258
6c90c872 1259config OABI_COMPAT
a73a3ff1 1260 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
d6f94fa0 1261 depends on AEABI && !THUMB2_KERNEL
6c90c872
NP
1262 help
1263 This option preserves the old syscall interface along with the
1264 new (ARM EABI) one. It also provides a compatibility layer to
1265 intercept syscalls that have structure arguments which layout
1266 in memory differs between the legacy ABI and the new ARM EABI
1267 (only for non "thumb" binaries). This option adds a tiny
1268 overhead to all syscalls and produces a slightly larger kernel.
91702175
KC
1269
1270 The seccomp filter system will not be available when this is
1271 selected, since there is no way yet to sensibly distinguish
1272 between calling conventions during filtering.
1273
6c90c872
NP
1274 If you know you'll be using only pure EABI user space then you
1275 can say N here. If this option is not selected and you attempt
1276 to execute a legacy ABI binary then the result will be
1277 UNPREDICTABLE (in fact it can be predicted that it won't work
b02f8467 1278 at all). If in doubt say N.
6c90c872 1279
fb597f2a 1280config ARCH_SELECT_MEMORY_MODEL
6fd09c9a 1281 def_bool y
fb597f2a
GF
1282
1283config ARCH_FLATMEM_ENABLE
6fd09c9a 1284 def_bool !(ARCH_RPC || ARCH_SA1100)
05944d74 1285
05944d74 1286config ARCH_SPARSEMEM_ENABLE
6fd09c9a 1287 def_bool !ARCH_FOOTBRIDGE
fb597f2a 1288 select SPARSEMEM_STATIC if SPARSEMEM
07a2f737 1289
053a96ca 1290config HIGHMEM
e8db89a2
RK
1291 bool "High Memory Support"
1292 depends on MMU
2a15ba82 1293 select KMAP_LOCAL
825c43f5 1294 select KMAP_LOCAL_NON_LINEAR_PTE_ARRAY
053a96ca
NP
1295 help
1296 The address space of ARM processors is only 4 Gigabytes large
1297 and it has to accommodate user address space, kernel address
1298 space as well as some memory mapped IO. That means that, if you
1299 have a large amount of physical memory and/or IO, not all of the
1300 memory can be "permanently mapped" by the kernel. The physical
1301 memory that is not permanently mapped is called "high memory".
1302
1303 Depending on the selected kernel/user memory split, minimum
1304 vmalloc space and actual amount of RAM, you may not need this
1305 option which should result in a slightly faster kernel.
1306
1307 If unsure, say n.
1308
65cec8e3 1309config HIGHPTE
9a431bd5 1310 bool "Allocate 2nd-level pagetables from highmem" if EXPERT
65cec8e3 1311 depends on HIGHMEM
9a431bd5 1312 default y
b4d103d1
RK
1313 help
1314 The VM uses one page of physical memory for each page table.
1315 For systems with a lot of processes, this can use a lot of
1316 precious low memory, eventually leading to low memory being
1317 consumed by page tables. Setting this option will allow
1318 user-space 2nd level page tables to reside in high memory.
65cec8e3 1319
a5e090ac
RK
1320config CPU_SW_DOMAIN_PAN
1321 bool "Enable use of CPU domains to implement privileged no-access"
1322 depends on MMU && !ARM_LPAE
1b8873a0
JI
1323 default y
1324 help
a5e090ac
RK
1325 Increase kernel security by ensuring that normal kernel accesses
1326 are unable to access userspace addresses. This can help prevent
1327 use-after-free bugs becoming an exploitable privilege escalation
1328 by ensuring that magic values (such as LIST_POISON) will always
1329 fault when dereferenced.
1330
1331 CPUs with low-vector mappings use a best-efforts implementation.
1332 Their lower 1MB needs to remain accessible for the vectors, but
1333 the remainder of userspace will become appropriately inaccessible.
65cec8e3 1334
1b8873a0 1335config HW_PERF_EVENTS
fa8ad788
MR
1336 def_bool y
1337 depends on ARM_PMU
1b8873a0 1338
7d485f64
AB
1339config ARM_MODULE_PLTS
1340 bool "Use PLTs to allow module memory to spill over into vmalloc area"
1341 depends on MODULES
8fa7ea40 1342 select KASAN_VMALLOC if KASAN
e7229f7d 1343 default y
7d485f64
AB
1344 help
1345 Allocate PLTs when loading modules so that jumps and calls whose
1346 targets are too far away for their relative offsets to be encoded
1347 in the instructions themselves can be bounced via veneers in the
1348 module's PLT. This allows modules to be allocated in the generic
1349 vmalloc area after the dedicated module memory area has been
1350 exhausted. The modules will use slightly more memory, but after
1351 rounding up to page size, the actual memory footprint is usually
1352 the same.
1353
e7229f7d
AR
1354 Disabling this is usually safe for small single-platform
1355 configurations. If unsure, say y.
7d485f64 1356
0192445c 1357config ARCH_FORCE_MAX_ORDER
8c907785 1358 int "Order of maximal physically contiguous allocations"
23baf831
KS
1359 default "11" if SOC_AM33XX
1360 default "8" if SA1111
1361 default "10"
c1b2d970 1362 help
8c907785
MRI
1363 The kernel page allocator limits the size of maximal physically
1364 contiguous allocations. The limit is called MAX_ORDER and it
1365 defines the maximal power of two of number of pages that can be
1366 allocated as a single contiguous block. This option allows
1367 overriding the default setting when ability to allocate very
1368 large blocks of physically contiguous memory is required.
1369
1370 Don't change if unsure.
c1b2d970 1371
1da177e4 1372config ALIGNMENT_TRAP
3e3f354b 1373 def_bool CPU_CP15_MMU
e119bfff 1374 select HAVE_PROC_CPU if PROC_FS
1da177e4 1375 help
84eb8d06 1376 ARM processors cannot fetch/store information which is not
1da177e4
LT
1377 naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1378 address divisible by 4. On 32-bit ARM processors, these non-aligned
1379 fetch/store instructions will be emulated in software if you say
1380 here, which has a severe performance impact. This is necessary for
1381 correct operation of some network protocols. With an IP-only
1382 configuration it is safe to say N, otherwise say Y.
1383
39ec58f3 1384config UACCESS_WITH_MEMCPY
38ef2ad5
LW
1385 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user()"
1386 depends on MMU
39ec58f3
LB
1387 default y if CPU_FEROCEON
1388 help
1389 Implement faster copy_to_user and clear_user methods for CPU
1390 cores where a 8-word STM instruction give significantly higher
1391 memory write throughput than a sequence of individual 32bit stores.
1392
1393 A possible side effect is a slight increase in scheduling latency
1394 between threads sharing the same address space if they invoke
1395 such copy operations with large buffers.
1396
1397 However, if the CPU data cache is using a write-allocate mode,
1398 this option is unlikely to provide any performance gain.
1399
02c2433b
SS
1400config PARAVIRT
1401 bool "Enable paravirtualization code"
1402 help
1403 This changes the kernel so it can modify itself when it is run
1404 under a hypervisor, potentially improving performance significantly
1405 over full virtualization.
1406
1407config PARAVIRT_TIME_ACCOUNTING
1408 bool "Paravirtual steal time accounting"
1409 select PARAVIRT
02c2433b
SS
1410 help
1411 Select this option to enable fine granularity task steal time
1412 accounting. Time spent executing other tasks in parallel with
1413 the current vCPU is discounted from the vCPU power. To account for
1414 that, there can be a small performance impact.
1415
1416 If in doubt, say N here.
1417
eff8d644
SS
1418config XEN_DOM0
1419 def_bool y
1420 depends on XEN
1421
1422config XEN
c2ba1f7d 1423 bool "Xen guest support on ARM"
85323a99 1424 depends on ARM && AEABI && OF
f880b67d 1425 depends on CPU_V7 && !CPU_V6
85323a99 1426 depends on !GENERIC_ATOMIC64
7693decc 1427 depends on MMU
51aaf81f 1428 select ARCH_DMA_ADDR_T_64BIT
17b7ab80 1429 select ARM_PSCI
f21254cd 1430 select SWIOTLB
83862ccf 1431 select SWIOTLB_XEN
02c2433b 1432 select PARAVIRT
eff8d644
SS
1433 help
1434 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
1435
f05eb1d2
AB
1436config CC_HAVE_STACKPROTECTOR_TLS
1437 def_bool $(cc-option,-mtp=cp15 -mstack-protector-guard=tls -mstack-protector-guard-offset=0)
1438
189af465
AB
1439config STACKPROTECTOR_PER_TASK
1440 bool "Use a unique stack canary value for each task"
9c46929e 1441 depends on STACKPROTECTOR && CURRENT_POINTER_IN_TPIDRURO && !XIP_DEFLATED_DATA
f05eb1d2
AB
1442 depends on GCC_PLUGINS || CC_HAVE_STACKPROTECTOR_TLS
1443 select GCC_PLUGIN_ARM_SSP_PER_TASK if !CC_HAVE_STACKPROTECTOR_TLS
189af465
AB
1444 default y
1445 help
1446 Due to the fact that GCC uses an ordinary symbol reference from
1447 which to load the value of the stack canary, this value can only
1448 change at reboot time on SMP systems, and all tasks running in the
1449 kernel's address space are forced to use the same canary value for
1450 the entire duration that the system is up.
1451
1452 Enable this option to switch to a different method that uses a
1453 different canary value for each task.
1454
1da177e4
LT
1455endmenu
1456
1457menu "Boot options"
1458
9eb8f674
GL
1459config USE_OF
1460 bool "Flattened Device Tree support"
b1b3f49c 1461 select IRQ_DOMAIN
9eb8f674 1462 select OF
9eb8f674
GL
1463 help
1464 Include support for flattened device tree machine descriptions.
1465
6a1d798f
RH
1466config ARCH_WANT_FLAT_DTB_INSTALL
1467 def_bool y
1468
bd51e2f5 1469config ATAGS
96a4ce30 1470 bool "Support for the traditional ATAGS boot data passing"
bd51e2f5
NP
1471 default y
1472 help
1473 This is the traditional way of passing data to the kernel at boot
1474 time. If you are solely relying on the flattened device tree (or
1475 the ARM_ATAG_DTB_COMPAT option) then you may unselect this option
acb926d6
AB
1476 to remove ATAGS support from your kernel binary.
1477
bd51e2f5
NP
1478config DEPRECATED_PARAM_STRUCT
1479 bool "Provide old way to pass kernel parameters"
1480 depends on ATAGS
1481 help
1482 This was deprecated in 2001 and announced to live on for 5 years.
1483 Some old boot loaders still use this way.
1484
1da177e4
LT
1485# Compressed boot loader in ROM. Yes, we really want to ask about
1486# TEXT and BSS so we preserve their values in the config files.
1487config ZBOOT_ROM_TEXT
1488 hex "Compressed ROM boot loader base address"
39c3e304 1489 default 0x0
1da177e4
LT
1490 help
1491 The physical address at which the ROM-able zImage is to be
1492 placed in the target. Platforms which normally make use of
1493 ROM-able zImage formats normally set this to a suitable
1494 value in their defconfig file.
1495
1496 If ZBOOT_ROM is not enabled, this has no effect.
1497
1498config ZBOOT_ROM_BSS
1499 hex "Compressed ROM boot loader BSS address"
39c3e304 1500 default 0x0
1da177e4 1501 help
f8c440b2
DF
1502 The base address of an area of read/write memory in the target
1503 for the ROM-able zImage which must be available while the
1504 decompressor is running. It must be large enough to hold the
1505 entire decompressed kernel plus an additional 128 KiB.
1506 Platforms which normally make use of ROM-able zImage formats
1507 normally set this to a suitable value in their defconfig file.
1da177e4
LT
1508
1509 If ZBOOT_ROM is not enabled, this has no effect.
1510
1511config ZBOOT_ROM
1512 bool "Compressed boot loader in ROM/flash"
1513 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
10968131 1514 depends on !ARM_APPENDED_DTB && !XIP_KERNEL && !AUTO_ZRELADDR
1da177e4
LT
1515 help
1516 Say Y here if you intend to execute your compressed kernel image
1517 (zImage) directly from ROM or flash. If unsure, say N.
1518
e2a6a3aa
JB
1519config ARM_APPENDED_DTB
1520 bool "Use appended device tree blob to zImage (EXPERIMENTAL)"
10968131 1521 depends on OF
e2a6a3aa
JB
1522 help
1523 With this option, the boot code will look for a device tree binary
1524 (DTB) appended to zImage
1525 (e.g. cat zImage <filename>.dtb > zImage_w_dtb).
1526
1527 This is meant as a backward compatibility convenience for those
1528 systems with a bootloader that can't be upgraded to accommodate
1529 the documented boot protocol using a device tree.
1530
1531 Beware that there is very little in terms of protection against
1532 this option being confused by leftover garbage in memory that might
1533 look like a DTB header after a reboot if no actual DTB is appended
1534 to zImage. Do not leave this option active in a production kernel
1535 if you don't intend to always append a DTB. Proper passing of the
1536 location into r2 of a bootloader provided DTB is always preferable
1537 to this option.
1538
b90b9a38
NP
1539config ARM_ATAG_DTB_COMPAT
1540 bool "Supplement the appended DTB with traditional ATAG information"
1541 depends on ARM_APPENDED_DTB
1542 help
1543 Some old bootloaders can't be updated to a DTB capable one, yet
1544 they provide ATAGs with memory configuration, the ramdisk address,
1545 the kernel cmdline string, etc. Such information is dynamically
1546 provided by the bootloader and can't always be stored in a static
1547 DTB. To allow a device tree enabled kernel to be used with such
1548 bootloaders, this option allows zImage to extract the information
1549 from the ATAG list and store it at run time into the appended DTB.
1550
d0f34a11
RG
1551choice
1552 prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT
1553 default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1554
1555config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1556 bool "Use bootloader kernel arguments if available"
1557 help
1558 Uses the command-line options passed by the boot loader instead of
1559 the device tree bootargs property. If the boot loader doesn't provide
1560 any, the device tree bootargs property will be used.
1561
1562config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND
1563 bool "Extend with bootloader kernel arguments"
1564 help
1565 The command-line arguments provided by the boot loader will be
1566 appended to the the device tree bootargs property.
1567
1568endchoice
1569
1da177e4
LT
1570config CMDLINE
1571 string "Default kernel command string"
1572 default ""
1573 help
3e3f354b 1574 On some architectures (e.g. CATS), there is currently no way
1da177e4
LT
1575 for the boot loader to pass arguments to the kernel. For these
1576 architectures, you should supply some command-line options at build
1577 time by entering them here. As a minimum, you should specify the
1578 memory size and the root device (e.g., mem=64M root=/dev/nfs).
1579
4394c124
VB
1580choice
1581 prompt "Kernel command line type" if CMDLINE != ""
1582 default CMDLINE_FROM_BOOTLOADER
1583
1584config CMDLINE_FROM_BOOTLOADER
1585 bool "Use bootloader kernel arguments if available"
1586 help
1587 Uses the command-line options passed by the boot loader. If
1588 the boot loader doesn't provide any, the default kernel command
1589 string provided in CMDLINE will be used.
1590
1591config CMDLINE_EXTEND
1592 bool "Extend bootloader kernel arguments"
1593 help
1594 The command-line arguments provided by the boot loader will be
1595 appended to the default kernel command string.
1596
92d2040d
AH
1597config CMDLINE_FORCE
1598 bool "Always use the default kernel command string"
92d2040d
AH
1599 help
1600 Always use the default kernel command string, even if the boot
1601 loader passes other arguments to the kernel.
1602 This is useful if you cannot or don't want to change the
1603 command-line options your boot loader passes to the kernel.
4394c124 1604endchoice
92d2040d 1605
1da177e4
LT
1606config XIP_KERNEL
1607 bool "Kernel Execute-In-Place from ROM"
10968131 1608 depends on !ARM_LPAE && !ARCH_MULTIPLATFORM
5408445b 1609 depends on !ARM_PATCH_IDIV && !ARM_PATCH_PHYS_VIRT && !SMP_ON_UP
1da177e4
LT
1610 help
1611 Execute-In-Place allows the kernel to run from non-volatile storage
1612 directly addressable by the CPU, such as NOR flash. This saves RAM
1613 space since the text section of the kernel is not loaded from flash
1614 to RAM. Read-write sections, such as the data section and stack,
1615 are still copied to RAM. The XIP kernel is not compressed since
1616 it has to run directly from flash, so it will take more space to
1617 store it. The flash address used to link the kernel object files,
1618 and for storing it, is configuration dependent. Therefore, if you
1619 say Y here, you must know the proper physical address where to
1620 store the kernel image depending on your own flash memory usage.
1621
1622 Also note that the make target becomes "make xipImage" rather than
1623 "make zImage" or "make Image". The final kernel binary to put in
1624 ROM memory will be arch/arm/boot/xipImage.
1625
1626 If unsure, say N.
1627
1628config XIP_PHYS_ADDR
1629 hex "XIP Kernel Physical Location"
1630 depends on XIP_KERNEL
1631 default "0x00080000"
1632 help
1633 This is the physical address in your flash memory the kernel will
1634 be linked for and stored to. This address is dependent on your
1635 own flash usage.
1636
ca8b5d97
NP
1637config XIP_DEFLATED_DATA
1638 bool "Store kernel .data section compressed in ROM"
1639 depends on XIP_KERNEL
1640 select ZLIB_INFLATE
1641 help
1642 Before the kernel is actually executed, its .data section has to be
1643 copied to RAM from ROM. This option allows for storing that data
1644 in compressed form and decompressed to RAM rather than merely being
1645 copied, saving some precious ROM space. A possible drawback is a
1646 slightly longer boot delay.
1647
c587e4a6
RP
1648config KEXEC
1649 bool "Kexec system call (EXPERIMENTAL)"
19ab428f 1650 depends on (!SMP || PM_SLEEP_SMP)
76950f71 1651 depends on MMU
2965faa5 1652 select KEXEC_CORE
c587e4a6
RP
1653 help
1654 kexec is a system call that implements the ability to shutdown your
1655 current kernel, and to start another kernel. It is like a reboot
01dd2fbf 1656 but it is independent of the system firmware. And like a reboot
c587e4a6
RP
1657 you can start any kernel with it, not just Linux.
1658
1659 It is an ongoing process to be certain the hardware in a machine
1660 is properly shutdown, so do not be surprised if this code does not
bf220695 1661 initially work for you.
c587e4a6 1662
4cd9d6f7
RP
1663config ATAGS_PROC
1664 bool "Export atags in procfs"
bd51e2f5 1665 depends on ATAGS && KEXEC
b98d7291 1666 default y
4cd9d6f7
RP
1667 help
1668 Should the atags used to boot the kernel be exported in an "atags"
1669 file in procfs. Useful with kexec.
1670
cb5d39b3
MW
1671config CRASH_DUMP
1672 bool "Build kdump crash kernel (EXPERIMENTAL)"
cb5d39b3
MW
1673 help
1674 Generate crash dump after being started by kexec. This should
1675 be normally only set in special crash dump kernels which are
1676 loaded in the main kernel with kexec-tools into a specially
1677 reserved region and then later executed after a crash by
1678 kdump/kexec. The crash dump kernel must be compiled to a
1679 memory address not used by the main kernel
1680
330d4810 1681 For more details see Documentation/admin-guide/kdump/kdump.rst
cb5d39b3 1682
e69edc79 1683config AUTO_ZRELADDR
6fd09c9a
AB
1684 bool "Auto calculation of the decompressed kernel image address" if !ARCH_MULTIPLATFORM
1685 default !(ARCH_FOOTBRIDGE || ARCH_RPC || ARCH_SA1100)
e69edc79
EM
1686 help
1687 ZRELADDR is the physical address where the decompressed kernel
1688 image will be placed. If AUTO_ZRELADDR is selected, the address
0673cb38
GU
1689 will be determined at run-time, either by masking the current IP
1690 with 0xf8000000, or, if invalid, from the DTB passed in r2.
1691 This assumes the zImage being placed in the first 128MB from
1692 start of memory.
e69edc79 1693
81a0bc39
RF
1694config EFI_STUB
1695 bool
1696
1697config EFI
1698 bool "UEFI runtime support"
1699 depends on OF && !CPU_BIG_ENDIAN && MMU && AUTO_ZRELADDR && !XIP_KERNEL
1700 select UCS2_STRING
1701 select EFI_PARAMS_FROM_FDT
1702 select EFI_STUB
2e0eb483 1703 select EFI_GENERIC_STUB
81a0bc39 1704 select EFI_RUNTIME_WRAPPERS
a7f7f624 1705 help
81a0bc39
RF
1706 This option provides support for runtime services provided
1707 by UEFI firmware (such as non-volatile variables, realtime
1708 clock, and platform reset). A UEFI stub is also provided to
1709 allow the kernel to be booted as an EFI application. This
1710 is only useful for kernels that may run on systems that have
1711 UEFI firmware.
1712
bb817bef
AB
1713config DMI
1714 bool "Enable support for SMBIOS (DMI) tables"
1715 depends on EFI
1716 default y
1717 help
1718 This enables SMBIOS/DMI feature for systems.
1719
1720 This option is only useful on systems that have UEFI firmware.
1721 However, even with this option, the resultant kernel should
1722 continue to boot on existing non-UEFI platforms.
1723
1724 NOTE: This does *NOT* enable or encourage the use of DMI quirks,
1725 i.e., the the practice of identifying the platform via DMI to
1726 decide whether certain workarounds for buggy hardware and/or
1727 firmware need to be enabled. This would require the DMI subsystem
1728 to be enabled much earlier than we do on ARM, which is non-trivial.
1729
1da177e4
LT
1730endmenu
1731
ac9d7efc 1732menu "CPU Power Management"
1da177e4 1733
1da177e4 1734source "drivers/cpufreq/Kconfig"
1da177e4 1735
ac9d7efc
RK
1736source "drivers/cpuidle/Kconfig"
1737
1738endmenu
1739
1da177e4
LT
1740menu "Floating point emulation"
1741
1742comment "At least one emulation must be selected"
1743
1744config FPE_NWFPE
1745 bool "NWFPE math emulation"
593c252a 1746 depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL
a7f7f624 1747 help
1da177e4
LT
1748 Say Y to include the NWFPE floating point emulator in the kernel.
1749 This is necessary to run most binaries. Linux does not currently
1750 support floating point hardware so you need to say Y here even if
1751 your machine has an FPA or floating point co-processor podule.
1752
1753 You may say N here if you are going to load the Acorn FPEmulator
1754 early in the bootup.
1755
1756config FPE_NWFPE_XP
1757 bool "Support extended precision"
bedf142b 1758 depends on FPE_NWFPE
1da177e4
LT
1759 help
1760 Say Y to include 80-bit support in the kernel floating-point
1761 emulator. Otherwise, only 32 and 64-bit support is compiled in.
1762 Note that gcc does not generate 80-bit operations by default,
1763 so in most cases this option only enlarges the size of the
1764 floating point emulator without any good reason.
1765
1766 You almost surely want to say N here.
1767
1768config FPE_FASTFPE
1769 bool "FastFPE math emulation (EXPERIMENTAL)"
d6f94fa0 1770 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3
a7f7f624 1771 help
1da177e4
LT
1772 Say Y here to include the FAST floating point emulator in the kernel.
1773 This is an experimental much faster emulator which now also has full
1774 precision for the mantissa. It does not support any exceptions.
1775 It is very simple, and approximately 3-6 times faster than NWFPE.
1776
1777 It should be sufficient for most programs. It may be not suitable
1778 for scientific calculations, but you have to check this for yourself.
1779 If you do not feel you need a faster FP emulation you should better
1780 choose NWFPE.
1781
1782config VFP
1783 bool "VFP-format floating point maths"
e399b1a4 1784 depends on CPU_V6 || CPU_V6K || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
1da177e4
LT
1785 help
1786 Say Y to include VFP support code in the kernel. This is needed
1787 if your hardware includes a VFP unit.
1788
e318b36e 1789 Please see <file:Documentation/arch/arm/vfp/release-notes.rst> for
1da177e4
LT
1790 release notes and additional status information.
1791
1792 Say N if your target does not have VFP hardware.
1793
25ebee02
CM
1794config VFPv3
1795 bool
1796 depends on VFP
1797 default y if CPU_V7
1798
b5872db4
CM
1799config NEON
1800 bool "Advanced SIMD (NEON) Extension support"
1801 depends on VFPv3 && CPU_V7
1802 help
1803 Say Y to include support code for NEON, the ARMv7 Advanced SIMD
1804 Extension.
1805
73c132c1
AB
1806config KERNEL_MODE_NEON
1807 bool "Support for NEON in kernel mode"
c4a30c3b 1808 depends on NEON && AEABI
73c132c1
AB
1809 help
1810 Say Y to include support for NEON in kernel mode.
1811
1da177e4
LT
1812endmenu
1813
1da177e4
LT
1814menu "Power management options"
1815
eceab4ac 1816source "kernel/power/Kconfig"
1da177e4 1817
f4cb5700 1818config ARCH_SUSPEND_POSSIBLE
19a0519d 1819 depends on CPU_ARM920T || CPU_ARM926T || CPU_FEROCEON || CPU_SA1100 || \
f0d75153 1820 CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7M || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK
f4cb5700
JB
1821 def_bool y
1822
15e0d9e3 1823config ARM_CPU_SUSPEND
8b6f2499 1824 def_bool PM_SLEEP || BL_SWITCHER || ARM_PSCI_FW
1b9bdf5c 1825 depends on ARCH_SUSPEND_POSSIBLE
15e0d9e3 1826
603fb42a
SC
1827config ARCH_HIBERNATION_POSSIBLE
1828 bool
1829 depends on MMU
1830 default y if ARCH_SUSPEND_POSSIBLE
1831
1da177e4
LT
1832endmenu
1833
2cbd1cc3 1834source "arch/arm/Kconfig.assembler"