xref: /linux/arch/arm/Kconfig (revision e318b36ed37d241eb279382bde587eabf1892e34)
1b2441318SGreg Kroah-Hartman# SPDX-License-Identifier: GPL-2.0
21da177e4SLinus Torvaldsconfig ARM
31da177e4SLinus Torvalds	bool
41da177e4SLinus Torvalds	default y
5942fa985SYury Norov	select ARCH_32BIT_OFF_T
6fed240d9SMasami Hiramatsu	select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE if HAVE_KRETPROBES && FRAME_POINTER && !ARM_UNWIND
7aef0f78eSChristoph Hellwig	select ARCH_HAS_BINFMT_FLAT
82792d84eSKees Cook	select ARCH_HAS_CURRENT_STACK_POINTER
9c7780ab5SVladimir Murzin	select ARCH_HAS_DEBUG_VIRTUAL if MMU
10419e2f18SChristoph Hellwig	select ARCH_HAS_DMA_WRITE_COMBINE if !ARM_DMA_MEM_BUFFERABLE
112b68f6caSKees Cook	select ARCH_HAS_ELF_RANDOMIZE
12ee333554SJinbum Park	select ARCH_HAS_FORTIFY_SOURCE
13d8ae8a37SChristoph Hellwig	select ARCH_HAS_KEEPINITRD
1475851720SDmitry Vyukov	select ARCH_HAS_KCOV
15e69244d2SWill Deacon	select ARCH_HAS_MEMBARRIER_SYNC_CORE
160ebeea8cSDaniel Borkmann	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
173010a5eaSLaurent Dufour	select ARCH_HAS_PTE_SPECIAL if ARM_LPAE
18347cb6afSChristoph Hellwig	select ARCH_HAS_SETUP_DMA_OPS
1975851720SDmitry Vyukov	select ARCH_HAS_SET_MEMORY
209fbed16cSLi Huafei	select ARCH_STACKWALK
21ad21fc4fSLaura Abbott	select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
22ad21fc4fSLaura Abbott	select ARCH_HAS_STRICT_MODULE_RWX if MMU
23ae626eb9SChristoph Hellwig	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
24ae626eb9SChristoph Hellwig	select ARCH_HAS_SYNC_DMA_FOR_CPU
25dc2acdedSChristoph Hellwig	select ARCH_HAS_TEARDOWN_DMA_OPS if MMU
263d06770eSMark Rutland	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
279aaf9bb7SDaniel Thompson	select ARCH_HAVE_NMI_SAFE_CMPXCHG if CPU_V7 || CPU_V7M || CPU_V6K
28957e3facSRiku Voipio	select ARCH_HAS_GCOV_PROFILE_ALL
295e545df3SMike Rapoport	select ARCH_KEEP_MEMBLOCK
30d539fee9SSeung-Woo Kim	select ARCH_HAS_UBSAN_SANITIZE_ALL
31d7018848SMark Salter	select ARCH_MIGHT_HAVE_PC_PARPORT
32ad21fc4fSLaura Abbott	select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
33ad21fc4fSLaura Abbott	select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT if CPU_V7
344badad35SPeter Zijlstra	select ARCH_SUPPORTS_ATOMIC_RMW
35855f9a8eSAnshuman Khandual	select ARCH_SUPPORTS_HUGETLBFS if ARM_LPAE
36017f161aSKim Phillips	select ARCH_USE_BUILTIN_BSWAP
370cbad9c9SWill Deacon	select ARCH_USE_CMPXCHG_LOCKREF
38dce44566SAnshuman Khandual	select ARCH_USE_MEMTEST
39dba79c3dSAlexandre Ghiti	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
4007431506SAnshuman Khandual	select ARCH_WANT_GENERAL_HUGETLB
41b1b3f49cSRussell King	select ARCH_WANT_IPC_PARSE_VERSION
4259612b24SNathan Chancellor	select ARCH_WANT_LD_ORPHAN_WARN
43bdd15a28SChristoph Hellwig	select BINFMT_FLAT_ARGVP_ENVP_ON_STACK
4410916706SShile Zhang	select BUILDTIME_TABLE_SORT if MMU
456fd09c9aSArnd Bergmann	select COMMON_CLK if !(ARCH_RPC || ARCH_FOOTBRIDGE)
46171b3f0dSRussell King	select CLONE_BACKWARDS
47f00790aaSRussell King	select CPU_PM if SUSPEND || CPU_IDLE
48dce5c9e3SWill Deacon	select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS
49ff4c25f2SChristoph Hellwig	select DMA_DECLARE_COHERENT
5031b089bbSChristoph Hellwig	select DMA_GLOBAL_POOL if !MMU
512f9237d4SChristoph Hellwig	select DMA_OPS
52f5ff79fdSChristoph Hellwig	select DMA_NONCOHERENT_MMAP if MMU
53b01aec9bSBorislav Petkov	select EDAC_SUPPORT
54b01aec9bSBorislav Petkov	select EDAC_ATOMIC_SCRUB
5536d0fd21SLaura Abbott	select GENERIC_ALLOCATOR
562ef7a295SJuri Lelli	select GENERIC_ARCH_TOPOLOGY if ARM_CPU_TOPOLOGY
57f00790aaSRussell King	select GENERIC_ATOMIC64 if CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI
58b1b3f49cSRussell King	select GENERIC_CLOCKEVENTS_BROADCAST if SMP
5956afcd3dSMarc Zyngier	select GENERIC_IRQ_IPI if SMP
60ea2d9a96SArd Biesheuvel	select GENERIC_CPU_AUTOPROBE
612937367bSArd Biesheuvel	select GENERIC_EARLY_IOREMAP
62171b3f0dSRussell King	select GENERIC_IDLE_POLL_SETUP
63234a0f20SArnd Bergmann	select GENERIC_IRQ_MULTI_HANDLER
64b1b3f49cSRussell King	select GENERIC_IRQ_PROBE
65b1b3f49cSRussell King	select GENERIC_IRQ_SHOW
667c07005eSGeert Uytterhoeven	select GENERIC_IRQ_SHOW_LEVEL
67914ee966SPalmer Dabbelt	select GENERIC_LIB_DEVMEM_IS_ALLOWED
68b1b3f49cSRussell King	select GENERIC_PCI_IOMAP
6938ff87f7SStephen Boyd	select GENERIC_SCHED_CLOCK
70b1b3f49cSRussell King	select GENERIC_SMP_IDLE_THREAD
71b1b3f49cSRussell King	select HARDIRQS_SW_RESEND
72fcbfe812SNiklas Schnelle	select HAS_IOPORT
73f00790aaSRussell King	select HAVE_ARCH_AUDITSYSCALL if AEABI && !OABI_COMPAT
740b7857dbSYalin Wang	select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
75437682eeSArnd Bergmann	select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
7675969686SWang Kefeng	select HAVE_ARCH_KFENCE if MMU && !XIP_KERNEL
77437682eeSArnd Bergmann	select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
7842101571SLinus Walleij	select HAVE_ARCH_KASAN if MMU && !XIP_KERNEL
79565cbaadSLecopzer Chen	select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN
80e0c25d95SDaniel Cashman	select HAVE_ARCH_MMAP_RND_BITS if MMU
814f5b0c17SMike Rapoport	select HAVE_ARCH_PFN_VALID
82282a181bSYiFei Zhu	select HAVE_ARCH_SECCOMP
83f00790aaSRussell King	select HAVE_ARCH_SECCOMP_FILTER if AEABI && !OABI_COMPAT
8408626a60SKees Cook	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
850693bf68SWade Farnsworth	select HAVE_ARCH_TRACEHOOK
86e8003bf6SAnshuman Khandual	select HAVE_ARCH_TRANSPARENT_HUGEPAGE if ARM_LPAE
87b329f95dSJens Wiklander	select HAVE_ARM_SMCCC if CPU_V7
8839c13c20SShubham Bansal	select HAVE_EBPF_JIT if !CPU_ENDIAN_BE32
8924a9c541SFrederic Weisbecker	select HAVE_CONTEXT_TRACKING_USER
90b1b3f49cSRussell King	select HAVE_C_RECORDMCOUNT
914ed308c4SSteven Rostedt (Google)	select HAVE_BUILDTIME_MCOUNT_SORT
92bc420c6cSVincenzo Frascino	select HAVE_DEBUG_KMEMLEAK if !XIP_KERNEL
93b1b3f49cSRussell King	select HAVE_DMA_CONTIGUOUS if MMU
94f00790aaSRussell King	select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
95620176f3SAbel Vesa	select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
96dce5c9e3SWill Deacon	select HAVE_EFFICIENT_UNALIGNED_ACCESS if (CPU_V6 || CPU_V6K || CPU_V7) && MMU
975f56a5dfSJiri Slaby	select HAVE_EXIT_THREAD
9867a929e0SChristoph Hellwig	select HAVE_FAST_GUP if ARM_LPAE
99f00790aaSRussell King	select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
100aaa4dd1bSWang Kefeng	select HAVE_FUNCTION_ERROR_INJECTION
10141918ec8SArd Biesheuvel	select HAVE_FUNCTION_GRAPH_TRACER
102d6800ca7SArd Biesheuvel	select HAVE_FUNCTION_TRACER if !XIP_KERNEL
1036b90bd4bSEmese Revfy	select HAVE_GCC_PLUGINS
104f00790aaSRussell King	select HAVE_HW_BREAKPOINT if PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7)
10587c46b6cSRussell King	select HAVE_IRQ_TIME_ACCOUNTING
106b1b3f49cSRussell King	select HAVE_KERNEL_GZIP
107f9b493acSKyungsik Lee	select HAVE_KERNEL_LZ4
108b1b3f49cSRussell King	select HAVE_KERNEL_LZMA
109b1b3f49cSRussell King	select HAVE_KERNEL_LZO
110b1b3f49cSRussell King	select HAVE_KERNEL_XZ
111cb1293e2SArnd Bergmann	select HAVE_KPROBES if !XIP_KERNEL && !CPU_ENDIAN_BE32 && !CPU_V7M
112f00790aaSRussell King	select HAVE_KRETPROBES if HAVE_KPROBES
1137d485f64SArd Biesheuvel	select HAVE_MOD_ARCH_SPECIFIC
11442a0bb3fSPetr Mladek	select HAVE_NMI
1150dc016dbSWang Nan	select HAVE_OPTPROBES if !THUMB2_KERNEL
11647723de8SArnd Bergmann	select HAVE_PCI if MMU
1177ada189fSJamie Iles	select HAVE_PERF_EVENTS
11849863894SWill Deacon	select HAVE_PERF_REGS
11949863894SWill Deacon	select HAVE_PERF_USER_STACK_DUMP
120ff2e6d72SPeter Zijlstra	select MMU_GATHER_RCU_TABLE_FREE if SMP && ARM_LPAE
121e513f8bfSWill Deacon	select HAVE_REGS_AND_STACK_ACCESS_API
1229800b9dcSMathieu Desnoyers	select HAVE_RSEQ
123d148eac0SMasahiro Yamada	select HAVE_STACKPROTECTOR
124b1b3f49cSRussell King	select HAVE_SYSCALL_TRACEPOINTS
125af1839ebSCatalin Marinas	select HAVE_UID16
12631c1fc81SKevin Hilman	select HAVE_VIRT_CPU_ACCOUNTING_GEN
127da0ec6f7SThomas Gleixner	select IRQ_FORCED_THREADING
128171b3f0dSRussell King	select MODULES_USE_ELF_REL
129f616ab59SChristoph Hellwig	select NEED_DMA_MAP_STATE
130aa7d5f18SArnd Bergmann	select OF_EARLY_FLATTREE if OF
131171b3f0dSRussell King	select OLD_SIGACTION
132171b3f0dSRussell King	select OLD_SIGSUSPEND3
1336fd09c9aSArnd Bergmann	select PCI_DOMAINS_GENERIC if PCI
13420f1b79dSChristoph Hellwig	select PCI_SYSCALL if PCI
135b1b3f49cSRussell King	select PERF_USE_VMALLOC
136b1b3f49cSRussell King	select RTC_LIB
1376fd09c9aSArnd Bergmann	select SPARSE_IRQ if !(ARCH_FOOTBRIDGE || ARCH_RPC)
138b1b3f49cSRussell King	select SYS_SUPPORTS_APM_EMULATION
1399c46929eSArd Biesheuvel	select THREAD_INFO_IN_TASK
1406fd09c9aSArnd Bergmann	select TIMER_OF if OF
141d6905849SArd Biesheuvel	select HAVE_ARCH_VMAP_STACK if MMU && ARM_HAS_GROUP_RELOCS
1424aae683fSMasahiro Yamada	select TRACE_IRQFLAGS_SUPPORT if !CPU_V7M
1436fd09c9aSArnd Bergmann	select USE_OF if !(ARCH_FOOTBRIDGE || ARCH_RPC || ARCH_SA1100)
144171b3f0dSRussell King	# Above selects are sorted alphabetically; please add new ones
145171b3f0dSRussell King	# according to that.  Thanks.
1461da177e4SLinus Torvalds	help
1471da177e4SLinus Torvalds	  The ARM series is a line of low-power-consumption RISC chip designs
148f6c8965aSMartin Michlmayr	  licensed by ARM Ltd and targeted at embedded applications and
1491da177e4SLinus Torvalds	  handhelds such as the Compaq IPAQ.  ARM-based PCs are no longer
1501da177e4SLinus Torvalds	  manufactured, but legacy ARM-based PC hardware remains popular in
1511da177e4SLinus Torvalds	  Europe.  There is an ARM Linux project with a web page at
1521da177e4SLinus Torvalds	  <http://www.arm.linux.org.uk/>.
1531da177e4SLinus Torvalds
154d6905849SArd Biesheuvelconfig ARM_HAS_GROUP_RELOCS
155d6905849SArd Biesheuvel	def_bool y
156d6905849SArd Biesheuvel	depends on !LD_IS_LLD || LLD_VERSION >= 140000
157d6905849SArd Biesheuvel	depends on !COMPILE_TEST
158d6905849SArd Biesheuvel	help
159d6905849SArd Biesheuvel	  Whether or not to use R_ARM_ALU_PC_Gn or R_ARM_LDR_PC_Gn group
160d6905849SArd Biesheuvel	  relocations, which have been around for a long time, but were not
161d6905849SArd Biesheuvel	  supported in LLD until version 14. The combined range is -/+ 256 MiB,
162d6905849SArd Biesheuvel	  which is usually sufficient, but not for allyesconfig, so we disable
163d6905849SArd Biesheuvel	  this feature when doing compile testing.
164d6905849SArd Biesheuvel
1654ce63fcdSMarek Szyprowskiconfig ARM_DMA_USE_IOMMU
1664ce63fcdSMarek Szyprowski	bool
167b1b3f49cSRussell King	select NEED_SG_DMA_LENGTH
1684ce63fcdSMarek Szyprowski
16960460abfSSeung-Woo Kimif ARM_DMA_USE_IOMMU
17060460abfSSeung-Woo Kim
17160460abfSSeung-Woo Kimconfig ARM_DMA_IOMMU_ALIGNMENT
17260460abfSSeung-Woo Kim	int "Maximum PAGE_SIZE order of alignment for DMA IOMMU buffers"
17360460abfSSeung-Woo Kim	range 4 9
17460460abfSSeung-Woo Kim	default 8
17560460abfSSeung-Woo Kim	help
17660460abfSSeung-Woo Kim	  DMA mapping framework by default aligns all buffers to the smallest
17760460abfSSeung-Woo Kim	  PAGE_SIZE order which is greater than or equal to the requested buffer
17860460abfSSeung-Woo Kim	  size. This works well for buffers up to a few hundreds kilobytes, but
17960460abfSSeung-Woo Kim	  for larger buffers it just a waste of address space. Drivers which has
18060460abfSSeung-Woo Kim	  relatively small addressing window (like 64Mib) might run out of
18160460abfSSeung-Woo Kim	  virtual space with just a few allocations.
18260460abfSSeung-Woo Kim
18360460abfSSeung-Woo Kim	  With this parameter you can specify the maximum PAGE_SIZE order for
18460460abfSSeung-Woo Kim	  DMA IOMMU buffers. Larger buffers will be aligned only to this
18560460abfSSeung-Woo Kim	  specified order. The order is expressed as a power of two multiplied
18660460abfSSeung-Woo Kim	  by the PAGE_SIZE.
18760460abfSSeung-Woo Kim
18860460abfSSeung-Woo Kimendif
18960460abfSSeung-Woo Kim
19075e7153aSRalf Baechleconfig SYS_SUPPORTS_APM_EMULATION
19175e7153aSRalf Baechle	bool
19275e7153aSRalf Baechle
193bc581770SLinus Walleijconfig HAVE_TCM
194bc581770SLinus Walleij	bool
195bc581770SLinus Walleij	select GENERIC_ALLOCATOR
196bc581770SLinus Walleij
197e119bfffSRussell Kingconfig HAVE_PROC_CPU
198e119bfffSRussell King	bool
199e119bfffSRussell King
200ce816fa8SUwe Kleine-Königconfig NO_IOPORT_MAP
2015ea81769SAl Viro	bool
2025ea81769SAl Viro
2031da177e4SLinus Torvaldsconfig SBUS
2041da177e4SLinus Torvalds	bool
2051da177e4SLinus Torvalds
206f16fb1ecSRussell Kingconfig STACKTRACE_SUPPORT
207f16fb1ecSRussell King	bool
208f16fb1ecSRussell King	default y
209f16fb1ecSRussell King
210f16fb1ecSRussell Kingconfig LOCKDEP_SUPPORT
211f16fb1ecSRussell King	bool
212f16fb1ecSRussell King	default y
213f16fb1ecSRussell King
214f0d1b0b3SDavid Howellsconfig ARCH_HAS_ILOG2_U32
215f0d1b0b3SDavid Howells	bool
216f0d1b0b3SDavid Howells
217f0d1b0b3SDavid Howellsconfig ARCH_HAS_ILOG2_U64
218f0d1b0b3SDavid Howells	bool
219f0d1b0b3SDavid Howells
2204a1b5733SEduardo Valentinconfig ARCH_HAS_BANDGAP
2214a1b5733SEduardo Valentin	bool
2224a1b5733SEduardo Valentin
223a5f4c561SStefan Agnerconfig FIX_EARLYCON_MEM
224a5f4c561SStefan Agner	def_bool y if MMU
225a5f4c561SStefan Agner
226b89c3b16SAkinobu Mitaconfig GENERIC_HWEIGHT
227b89c3b16SAkinobu Mita	bool
228b89c3b16SAkinobu Mita	default y
229b89c3b16SAkinobu Mita
2301da177e4SLinus Torvaldsconfig GENERIC_CALIBRATE_DELAY
2311da177e4SLinus Torvalds	bool
2321da177e4SLinus Torvalds	default y
2331da177e4SLinus Torvalds
234a08b6b79Sviro@ZenIV.linux.org.ukconfig ARCH_MAY_HAVE_PC_FDC
235a08b6b79Sviro@ZenIV.linux.org.uk	bool
236a08b6b79Sviro@ZenIV.linux.org.uk
237c7edc9e3SDavid A. Longconfig ARCH_SUPPORTS_UPROBES
238c7edc9e3SDavid A. Long	def_bool y
239c7edc9e3SDavid A. Long
2401da177e4SLinus Torvaldsconfig GENERIC_ISA_DMA
2411da177e4SLinus Torvalds	bool
2421da177e4SLinus Torvalds
2431da177e4SLinus Torvaldsconfig FIQ
2441da177e4SLinus Torvalds	bool
2451da177e4SLinus Torvalds
246034d2f5aSAl Viroconfig ARCH_MTD_XIP
247034d2f5aSAl Viro	bool
248034d2f5aSAl Viro
249dc21af99SRussell Kingconfig ARM_PATCH_PHYS_VIRT
250c1becedcSRussell King	bool "Patch physical to virtual translations at runtime" if EMBEDDED
251c1becedcSRussell King	default y
2525408445bSArnd Bergmann	depends on MMU
253dc21af99SRussell King	help
254111e9a5cSRussell King	  Patch phys-to-virt and virt-to-phys translation functions at
255111e9a5cSRussell King	  boot and module load time according to the position of the
256111e9a5cSRussell King	  kernel in system memory.
257dc21af99SRussell King
258111e9a5cSRussell King	  This can only be used with non-XIP MMU kernels where the base
2599443076eSArd Biesheuvel	  of physical memory is at a 2 MiB boundary.
260dc21af99SRussell King
261c1becedcSRussell King	  Only disable this option if you know that you do not require
262c1becedcSRussell King	  this feature (eg, building a kernel for a single machine) and
263c1becedcSRussell King	  you need to shrink the kernel to the minimal size.
264c1becedcSRussell King
265c334bc15SRob Herringconfig NEED_MACH_IO_H
266c334bc15SRob Herring	bool
267c334bc15SRob Herring	help
268c334bc15SRob Herring	  Select this when mach/io.h is required to provide special
269c334bc15SRob Herring	  definitions for this platform.  The need for mach/io.h should
270c334bc15SRob Herring	  be avoided when possible.
271c334bc15SRob Herring
2720cdc8b92SNicolas Pitreconfig NEED_MACH_MEMORY_H
2731b9f95f8SNicolas Pitre	bool
274111e9a5cSRussell King	help
2750cdc8b92SNicolas Pitre	  Select this when mach/memory.h is required to provide special
2760cdc8b92SNicolas Pitre	  definitions for this platform.  The need for mach/memory.h should
2770cdc8b92SNicolas Pitre	  be avoided when possible.
2781b9f95f8SNicolas Pitre
2791b9f95f8SNicolas Pitreconfig PHYS_OFFSET
280974c0724SNicolas Pitre	hex "Physical address of main memory" if MMU
28192481c7dSArnd Bergmann	depends on !ARM_PATCH_PHYS_VIRT || !AUTO_ZRELADDR
282974c0724SNicolas Pitre	default DRAM_BASE if !MMU
28306954b6aSLinus Walleij	default 0x00000000 if ARCH_FOOTBRIDGE
284c6f54a9bSUwe Kleine-König	default 0x10000000 if ARCH_OMAP1 || ARCH_RPC
285b91a69d1SArnd Bergmann	default 0xa0000000 if ARCH_PXA
286c6e77bb6SArnd Bergmann	default 0xc0000000 if ARCH_EP93XX || ARCH_SA1100
287c6e77bb6SArnd Bergmann	default 0
2881b9f95f8SNicolas Pitre	help
2891b9f95f8SNicolas Pitre	  Please provide the physical address corresponding to the
2901b9f95f8SNicolas Pitre	  location of main memory in your system.
291cada3c08SRussell King
29287e040b6SSimon Glassconfig GENERIC_BUG
29387e040b6SSimon Glass	def_bool y
29487e040b6SSimon Glass	depends on BUG
29587e040b6SSimon Glass
2961bcad26eSKirill A. Shutemovconfig PGTABLE_LEVELS
2971bcad26eSKirill A. Shutemov	int
2981bcad26eSKirill A. Shutemov	default 3 if ARM_LPAE
2991bcad26eSKirill A. Shutemov	default 2
3001bcad26eSKirill A. Shutemov
3011da177e4SLinus Torvaldsmenu "System Type"
3021da177e4SLinus Torvalds
3033c427975SHyok S. Choiconfig MMU
3043c427975SHyok S. Choi	bool "MMU-based Paged Memory Management Support"
3053c427975SHyok S. Choi	default y
3063c427975SHyok S. Choi	help
3073c427975SHyok S. Choi	  Select if you want MMU-based virtualised addressing space
3083c427975SHyok S. Choi	  support by paged memory management. If unsure, say 'Y'.
3093c427975SHyok S. Choi
3102f618d5eSArnd Bergmannconfig ARM_SINGLE_ARMV7M
3112f618d5eSArnd Bergmann	def_bool !MMU
3122f618d5eSArnd Bergmann	select ARM_NVIC
3132f618d5eSArnd Bergmann	select CPU_V7M
3142f618d5eSArnd Bergmann	select NO_IOPORT_MAP
3152f618d5eSArnd Bergmann
316e0c25d95SDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MIN
317e0c25d95SDaniel Cashman	default 8
318e0c25d95SDaniel Cashman
319e0c25d95SDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MAX
320e0c25d95SDaniel Cashman	default 14 if PAGE_OFFSET=0x40000000
321e0c25d95SDaniel Cashman	default 15 if PAGE_OFFSET=0x80000000
322e0c25d95SDaniel Cashman	default 16
323e0c25d95SDaniel Cashman
324387798b3SRob Herringconfig ARCH_MULTIPLATFORM
32584fc8636SArnd Bergmann	bool "Require kernel to be portable to multiple machines" if EXPERT
32684fc8636SArnd Bergmann	depends on MMU && !(ARCH_FOOTBRIDGE || ARCH_RPC || ARCH_SA1100)
32784fc8636SArnd Bergmann	default y
328f999b8bdSMartin Michlmayr	help
32984fc8636SArnd Bergmann	  In general, all Arm machines can be supported in a single
33084fc8636SArnd Bergmann	  kernel image, covering either Armv4/v5 or Armv6/v7.
3311da177e4SLinus Torvalds
33284fc8636SArnd Bergmann	  However, some configuration options require hardcoding machine
33384fc8636SArnd Bergmann	  specific physical addresses or enable errata workarounds that may
33484fc8636SArnd Bergmann	  break other machines.
3351da177e4SLinus Torvalds
33684fc8636SArnd Bergmann	  Selecting N here allows using those options, including
33784fc8636SArnd Bergmann	  DEBUG_UNCOMPRESS, XIP_KERNEL and ZBOOT_ROM. If unsure, say Y.
3381da177e4SLinus Torvalds
3396fd09c9aSArnd Bergmannmenu "Platform selection"
3406fd09c9aSArnd Bergmann	depends on MMU
341387798b3SRob Herring
342387798b3SRob Herringcomment "CPU Core family selection"
343387798b3SRob Herring
344f8afae40SArnd Bergmannconfig ARCH_MULTI_V4
3456fd09c9aSArnd Bergmann	bool "ARMv4 based platforms (FA526, StrongARM)"
346f8afae40SArnd Bergmann	depends on !ARCH_MULTI_V6_V7
3475eb6e280SNathan Chancellor	# https://github.com/llvm/llvm-project/issues/50764
3485eb6e280SNathan Chancellor	depends on !LD_IS_LLD || LLD_VERSION >= 160000
349f8afae40SArnd Bergmann	select ARCH_MULTI_V4_V5
3506fd09c9aSArnd Bergmann	select CPU_FA526 if !(CPU_SA110 || CPU_SA1100)
351f8afae40SArnd Bergmann
352387798b3SRob Herringconfig ARCH_MULTI_V4T
353387798b3SRob Herring	bool "ARMv4T based platforms (ARM720T, ARM920T, ...)"
354387798b3SRob Herring	depends on !ARCH_MULTI_V6_V7
3555eb6e280SNathan Chancellor	# https://github.com/llvm/llvm-project/issues/50764
3565eb6e280SNathan Chancellor	depends on !LD_IS_LLD || LLD_VERSION >= 160000
357b1b3f49cSRussell King	select ARCH_MULTI_V4_V5
35824e860fbSArnd Bergmann	select CPU_ARM920T if !(CPU_ARM7TDMI || CPU_ARM720T || \
35924e860fbSArnd Bergmann		CPU_ARM740T || CPU_ARM9TDMI || CPU_ARM922T || \
36024e860fbSArnd Bergmann		CPU_ARM925T || CPU_ARM940T)
361387798b3SRob Herring
362387798b3SRob Herringconfig ARCH_MULTI_V5
363387798b3SRob Herring	bool "ARMv5 based platforms (ARM926T, XSCALE, PJ1, ...)"
364387798b3SRob Herring	depends on !ARCH_MULTI_V6_V7
365b1b3f49cSRussell King	select ARCH_MULTI_V4_V5
36612567bbdSAndrew Lunn	select CPU_ARM926T if !(CPU_ARM946E || CPU_ARM1020 || \
36724e860fbSArnd Bergmann		CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || \
36824e860fbSArnd Bergmann		CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_FEROCEON)
369387798b3SRob Herring
370387798b3SRob Herringconfig ARCH_MULTI_V4_V5
371387798b3SRob Herring	bool
372387798b3SRob Herring
373387798b3SRob Herringconfig ARCH_MULTI_V6
3748dda05ccSStephen Boyd	bool "ARMv6 based platforms (ARM11)"
375387798b3SRob Herring	select ARCH_MULTI_V6_V7
37642f4754aSRob Herring	select CPU_V6K
377387798b3SRob Herring
378387798b3SRob Herringconfig ARCH_MULTI_V7
3798dda05ccSStephen Boyd	bool "ARMv7 based platforms (Cortex-A, PJ4, Scorpion, Krait)"
380387798b3SRob Herring	default y
381387798b3SRob Herring	select ARCH_MULTI_V6_V7
382b1b3f49cSRussell King	select CPU_V7
38390bc8ac7SRob Herring	select HAVE_SMP
384387798b3SRob Herring
385387798b3SRob Herringconfig ARCH_MULTI_V6_V7
386387798b3SRob Herring	bool
3879352b05bSRob Herring	select MIGHT_HAVE_CACHE_L2X0
388387798b3SRob Herring
389387798b3SRob Herringconfig ARCH_MULTI_CPU_AUTO
390387798b3SRob Herring	def_bool !(ARCH_MULTI_V4 || ARCH_MULTI_V4T || ARCH_MULTI_V6_V7)
391387798b3SRob Herring	select ARCH_MULTI_V5
392387798b3SRob Herring
393387798b3SRob Herringendmenu
394387798b3SRob Herring
39505e2a3deSRob Herringconfig ARCH_VIRT
396e3246542SMasahiro Yamada	bool "Dummy Virtual Machine"
397e3246542SMasahiro Yamada	depends on ARCH_MULTI_V7
3984b8b5f25SRob Herring	select ARM_AMBA
39905e2a3deSRob Herring	select ARM_GIC
4003ee80364SArnd Bergmann	select ARM_GIC_V2M if PCI
4010b28f1dbSJean-Philippe Brucker	select ARM_GIC_V3
402bb29cecbSVladimir Murzin	select ARM_GIC_V3_ITS if PCI
40305e2a3deSRob Herring	select ARM_PSCI
4044b8b5f25SRob Herring	select HAVE_ARM_ARCH_TIMER
40505e2a3deSRob Herring
4062cf1c348SJohn Crispinconfig ARCH_AIROHA
4072cf1c348SJohn Crispin	bool "Airoha SoC Support"
4082cf1c348SJohn Crispin	depends on ARCH_MULTI_V7
4092cf1c348SJohn Crispin	select ARM_AMBA
4102cf1c348SJohn Crispin	select ARM_GIC
4112cf1c348SJohn Crispin	select ARM_GIC_V3
4122cf1c348SJohn Crispin	select ARM_PSCI
4132cf1c348SJohn Crispin	select HAVE_ARM_ARCH_TIMER
4142cf1c348SJohn Crispin	help
4152cf1c348SJohn Crispin	  Support for Airoha EN7523 SoCs
4162cf1c348SJohn Crispin
417ccf50e23SRussell King#
418ccf50e23SRussell King# This is sorted alphabetically by mach-* pathname.  However, plat-*
419ccf50e23SRussell King# Kconfigs may be included either alphabetically (according to the
420ccf50e23SRussell King# plat- suffix) or along side the corresponding mach-* source.
421ccf50e23SRussell King#
4226bb8536cSAndreas Färbersource "arch/arm/mach-actions/Kconfig"
4236bb8536cSAndreas Färber
424445d9b30STsahee Zidenbergsource "arch/arm/mach-alpine/Kconfig"
425445d9b30STsahee Zidenberg
426590b460cSLars Perssonsource "arch/arm/mach-artpec/Kconfig"
427590b460cSLars Persson
428d9bfc86dSOleksij Rempelsource "arch/arm/mach-asm9260/Kconfig"
429d9bfc86dSOleksij Rempel
430a66c51f9SAlexandre Bellonisource "arch/arm/mach-aspeed/Kconfig"
431a66c51f9SAlexandre Belloni
43295b8f20fSRussell Kingsource "arch/arm/mach-at91/Kconfig"
43395b8f20fSRussell King
4341d22924eSAnders Bergsource "arch/arm/mach-axxia/Kconfig"
4351d22924eSAnders Berg
4368ac49e04SChristian Daudtsource "arch/arm/mach-bcm/Kconfig"
4378ac49e04SChristian Daudt
4381c37fa10SSebastian Hesselbarthsource "arch/arm/mach-berlin/Kconfig"
4391c37fa10SSebastian Hesselbarth
4401da177e4SLinus Torvaldssource "arch/arm/mach-clps711x/Kconfig"
4411da177e4SLinus Torvalds
44295b8f20fSRussell Kingsource "arch/arm/mach-davinci/Kconfig"
44395b8f20fSRussell King
444df8d742eSBaruch Siachsource "arch/arm/mach-digicolor/Kconfig"
445df8d742eSBaruch Siach
44695b8f20fSRussell Kingsource "arch/arm/mach-dove/Kconfig"
44795b8f20fSRussell King
448e7736d47SLennert Buytenheksource "arch/arm/mach-ep93xx/Kconfig"
449e7736d47SLennert Buytenhek
450a66c51f9SAlexandre Bellonisource "arch/arm/mach-exynos/Kconfig"
451a66c51f9SAlexandre Belloni
4521da177e4SLinus Torvaldssource "arch/arm/mach-footbridge/Kconfig"
4531da177e4SLinus Torvalds
45459d3a193SPaulius Zaleckassource "arch/arm/mach-gemini/Kconfig"
45559d3a193SPaulius Zaleckas
456387798b3SRob Herringsource "arch/arm/mach-highbank/Kconfig"
457387798b3SRob Herring
458389ee0c2SHaojian Zhuangsource "arch/arm/mach-hisi/Kconfig"
459389ee0c2SHaojian Zhuang
46011d89440SNick Hawkinssource "arch/arm/mach-hpe/Kconfig"
46111d89440SNick Hawkins
462a66c51f9SAlexandre Bellonisource "arch/arm/mach-imx/Kconfig"
463a66c51f9SAlexandre Belloni
4641da177e4SLinus Torvaldssource "arch/arm/mach-ixp4xx/Kconfig"
4651da177e4SLinus Torvalds
466828989adSSantosh Shilimkarsource "arch/arm/mach-keystone/Kconfig"
467828989adSSantosh Shilimkar
46875bf1bd7SArnd Bergmannsource "arch/arm/mach-lpc32xx/Kconfig"
46995b8f20fSRussell King
470a66c51f9SAlexandre Bellonisource "arch/arm/mach-mediatek/Kconfig"
471a66c51f9SAlexandre Belloni
4723b8f5030SCarlo Caionesource "arch/arm/mach-meson/Kconfig"
4733b8f5030SCarlo Caione
4749fb29c73SSugaya Taichisource "arch/arm/mach-milbeaut/Kconfig"
4759fb29c73SSugaya Taichi
476a66c51f9SAlexandre Bellonisource "arch/arm/mach-mmp/Kconfig"
477a66c51f9SAlexandre Belloni
47817723fd3SJonas Jensensource "arch/arm/mach-moxart/Kconfig"
47917723fd3SJonas Jensen
480312b62b6SDaniel Palmersource "arch/arm/mach-mstar/Kconfig"
481312b62b6SDaniel Palmer
482794d15b2SStanislav Samsonovsource "arch/arm/mach-mv78xx0/Kconfig"
483794d15b2SStanislav Samsonov
484a66c51f9SAlexandre Bellonisource "arch/arm/mach-mvebu/Kconfig"
485f682a218SMatthias Brugger
4861d3f33d5SShawn Guosource "arch/arm/mach-mxs/Kconfig"
4871d3f33d5SShawn Guo
48895b8f20fSRussell Kingsource "arch/arm/mach-nomadik/Kconfig"
48995b8f20fSRussell King
4907bffa14cSBrendan Higginssource "arch/arm/mach-npcm/Kconfig"
4917bffa14cSBrendan Higgins
4929851ca57SDaniel Tangsource "arch/arm/mach-nspire/Kconfig"
4939851ca57SDaniel Tang
494d48af15eSTony Lindgrensource "arch/arm/mach-omap1/Kconfig"
4951da177e4SLinus Torvalds
4961dbae815STony Lindgrensource "arch/arm/mach-omap2/Kconfig"
4971dbae815STony Lindgren
4989dd0b194SLennert Buytenheksource "arch/arm/mach-orion5x/Kconfig"
499585cf175STzachi Perelstein
50095b8f20fSRussell Kingsource "arch/arm/mach-pxa/Kconfig"
5011da177e4SLinus Torvalds
5028fc1b0f8SKumar Galasource "arch/arm/mach-qcom/Kconfig"
5038fc1b0f8SKumar Gala
50478e3dbc1SAndreas Färbersource "arch/arm/mach-rda/Kconfig"
50578e3dbc1SAndreas Färber
50686aeee4dSAndreas Färbersource "arch/arm/mach-realtek/Kconfig"
50786aeee4dSAndreas Färber
5086fd09c9aSArnd Bergmannsource "arch/arm/mach-rpc/Kconfig"
5096fd09c9aSArnd Bergmann
510d63dc051SHeiko Stuebnersource "arch/arm/mach-rockchip/Kconfig"
511d63dc051SHeiko Stuebner
51271b9114dSArnd Bergmannsource "arch/arm/mach-s3c/Kconfig"
513a66c51f9SAlexandre Belloni
514a66c51f9SAlexandre Bellonisource "arch/arm/mach-s5pv210/Kconfig"
515a66c51f9SAlexandre Belloni
51695b8f20fSRussell Kingsource "arch/arm/mach-sa1100/Kconfig"
517edabd38eSSaeed Bishara
518a66c51f9SAlexandre Bellonisource "arch/arm/mach-shmobile/Kconfig"
519a66c51f9SAlexandre Belloni
520387798b3SRob Herringsource "arch/arm/mach-socfpga/Kconfig"
521387798b3SRob Herring
522a7ed099fSArnd Bergmannsource "arch/arm/mach-spear/Kconfig"
523a21765a7SBen Dooks
52465ebcc11SSrinivas Kandagatlasource "arch/arm/mach-sti/Kconfig"
52565ebcc11SSrinivas Kandagatla
526bcb84fb4SAlexandre TORGUEsource "arch/arm/mach-stm32/Kconfig"
527bcb84fb4SAlexandre TORGUE
5280aa94eeaSQin Jiansource "arch/arm/mach-sunplus/Kconfig"
5290aa94eeaSQin Jian
5303b52634fSMaxime Ripardsource "arch/arm/mach-sunxi/Kconfig"
5313b52634fSMaxime Ripard
532c5f80065SErik Gillingsource "arch/arm/mach-tegra/Kconfig"
533c5f80065SErik Gilling
534ba56a987SMasahiro Yamadasource "arch/arm/mach-uniphier/Kconfig"
535ba56a987SMasahiro Yamada
53695b8f20fSRussell Kingsource "arch/arm/mach-ux500/Kconfig"
5371da177e4SLinus Torvalds
5381da177e4SLinus Torvaldssource "arch/arm/mach-versatile/Kconfig"
5391da177e4SLinus Torvalds
5406f35f9a9STony Prisksource "arch/arm/mach-vt8500/Kconfig"
5416f35f9a9STony Prisk
5429a45eb69SJosh Cartwrightsource "arch/arm/mach-zynq/Kconfig"
5439a45eb69SJosh Cartwright
544499f1640SStefan Agner# ARMv7-M architecture
545499f1640SStefan Agnerconfig ARCH_LPC18XX
546499f1640SStefan Agner	bool "NXP LPC18xx/LPC43xx"
547499f1640SStefan Agner	depends on ARM_SINGLE_ARMV7M
548499f1640SStefan Agner	select ARCH_HAS_RESET_CONTROLLER
549499f1640SStefan Agner	select ARM_AMBA
550499f1640SStefan Agner	select CLKSRC_LPC32XX
551499f1640SStefan Agner	select PINCTRL
552499f1640SStefan Agner	help
553499f1640SStefan Agner	  Support for NXP's LPC18xx Cortex-M3 and LPC43xx Cortex-M4
554499f1640SStefan Agner	  high performance microcontrollers.
555499f1640SStefan Agner
5561847119dSVladimir Murzinconfig ARCH_MPS2
55717bd274eSBaruch Siach	bool "ARM MPS2 platform"
5581847119dSVladimir Murzin	depends on ARM_SINGLE_ARMV7M
5591847119dSVladimir Murzin	select ARM_AMBA
5601847119dSVladimir Murzin	select CLKSRC_MPS2
5611847119dSVladimir Murzin	help
5621847119dSVladimir Murzin	  Support for Cortex-M Prototyping System (or V2M-MPS2) which comes
5631847119dSVladimir Murzin	  with a range of available cores like Cortex-M3/M4/M7.
5641847119dSVladimir Murzin
5651847119dSVladimir Murzin	  Please, note that depends which Application Note is used memory map
5661847119dSVladimir Murzin	  for the platform may vary, so adjustment of RAM base might be needed.
5671847119dSVladimir Murzin
5681da177e4SLinus Torvalds# Definitions to make life easier
5691da177e4SLinus Torvaldsconfig ARCH_ACORN
5701da177e4SLinus Torvalds	bool
5711da177e4SLinus Torvalds
57269b02f6aSLennert Buytenhekconfig PLAT_ORION
57369b02f6aSLennert Buytenhek	bool
574bfe45e0bSRussell King	select CLKSRC_MMIO
575dc7ad3b3SRussell King	select GENERIC_IRQ_CHIP
576278b45b0SAndrew Lunn	select IRQ_DOMAIN
57769b02f6aSLennert Buytenhek
578abcda1dcSThomas Petazzoniconfig PLAT_ORION_LEGACY
579abcda1dcSThomas Petazzoni	bool
580abcda1dcSThomas Petazzoni	select PLAT_ORION
581abcda1dcSThomas Petazzoni
582f4b8b319SRussell Kingconfig PLAT_VERSATILE
583f4b8b319SRussell King	bool
584f4b8b319SRussell King
5858636a1f9SMasahiro Yamadasource "arch/arm/mm/Kconfig"
5861da177e4SLinus Torvalds
587afe4b25eSLennert Buytenhekconfig IWMMXT
588d93003e8SSebastian Hesselbarth	bool "Enable iWMMXt support"
589d93003e8SSebastian Hesselbarth	depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B
590d93003e8SSebastian Hesselbarth	default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 || CPU_PJ4B
591afe4b25eSLennert Buytenhek	help
592afe4b25eSLennert Buytenhek	  Enable support for iWMMXt context switching at run time if
593afe4b25eSLennert Buytenhek	  running on a CPU that supports it.
594afe4b25eSLennert Buytenhek
5953b93e7b0SHyok S. Choiif !MMU
5963b93e7b0SHyok S. Choisource "arch/arm/Kconfig-nommu"
5973b93e7b0SHyok S. Choiendif
5983b93e7b0SHyok S. Choi
5993e0a07f8SGregory CLEMENTconfig PJ4B_ERRATA_4742
6003e0a07f8SGregory CLEMENT	bool "PJ4B Errata 4742: IDLE Wake Up Commands can Cause the CPU Core to Cease Operation"
6013e0a07f8SGregory CLEMENT	depends on CPU_PJ4B && MACH_ARMADA_370
6023e0a07f8SGregory CLEMENT	default y
6033e0a07f8SGregory CLEMENT	help
6043e0a07f8SGregory CLEMENT	  When coming out of either a Wait for Interrupt (WFI) or a Wait for
6053e0a07f8SGregory CLEMENT	  Event (WFE) IDLE states, a specific timing sensitivity exists between
6063e0a07f8SGregory CLEMENT	  the retiring WFI/WFE instructions and the newly issued subsequent
6073e0a07f8SGregory CLEMENT	  instructions.  This sensitivity can result in a CPU hang scenario.
6083e0a07f8SGregory CLEMENT	  Workaround:
6093e0a07f8SGregory CLEMENT	  The software must insert either a Data Synchronization Barrier (DSB)
6103e0a07f8SGregory CLEMENT	  or Data Memory Barrier (DMB) command immediately after the WFI/WFE
6113e0a07f8SGregory CLEMENT	  instruction
6123e0a07f8SGregory CLEMENT
613f0c4b8d6SWill Deaconconfig ARM_ERRATA_326103
614f0c4b8d6SWill Deacon	bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory"
615f0c4b8d6SWill Deacon	depends on CPU_V6
616f0c4b8d6SWill Deacon	help
617f0c4b8d6SWill Deacon	  Executing a SWP instruction to read-only memory does not set bit 11
618f0c4b8d6SWill Deacon	  of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to
619f0c4b8d6SWill Deacon	  treat the access as a read, preventing a COW from occurring and
620f0c4b8d6SWill Deacon	  causing the faulting task to livelock.
621f0c4b8d6SWill Deacon
6229cba3cccSCatalin Marinasconfig ARM_ERRATA_411920
6239cba3cccSCatalin Marinas	bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
624e399b1a4SRussell King	depends on CPU_V6 || CPU_V6K
6259cba3cccSCatalin Marinas	help
6269cba3cccSCatalin Marinas	  Invalidation of the Instruction Cache operation can
6279cba3cccSCatalin Marinas	  fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
6289cba3cccSCatalin Marinas	  It does not affect the MPCore. This option enables the ARM Ltd.
6299cba3cccSCatalin Marinas	  recommended workaround.
6309cba3cccSCatalin Marinas
6317ce236fcSCatalin Marinasconfig ARM_ERRATA_430973
6327ce236fcSCatalin Marinas	bool "ARM errata: Stale prediction on replaced interworking branch"
6337ce236fcSCatalin Marinas	depends on CPU_V7
6347ce236fcSCatalin Marinas	help
6357ce236fcSCatalin Marinas	  This option enables the workaround for the 430973 Cortex-A8
63679403cdaSRussell King	  r1p* erratum. If a code sequence containing an ARM/Thumb
6377ce236fcSCatalin Marinas	  interworking branch is replaced with another code sequence at the
6387ce236fcSCatalin Marinas	  same virtual address, whether due to self-modifying code or virtual
6397ce236fcSCatalin Marinas	  to physical address re-mapping, Cortex-A8 does not recover from the
6407ce236fcSCatalin Marinas	  stale interworking branch prediction. This results in Cortex-A8
6417ce236fcSCatalin Marinas	  executing the new code sequence in the incorrect ARM or Thumb state.
6427ce236fcSCatalin Marinas	  The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
6437ce236fcSCatalin Marinas	  and also flushes the branch target cache at every context switch.
6447ce236fcSCatalin Marinas	  Note that setting specific bits in the ACTLR register may not be
6457ce236fcSCatalin Marinas	  available in non-secure mode.
6467ce236fcSCatalin Marinas
647855c551fSCatalin Marinasconfig ARM_ERRATA_458693
648855c551fSCatalin Marinas	bool "ARM errata: Processor deadlock when a false hazard is created"
649855c551fSCatalin Marinas	depends on CPU_V7
65062e4d357SRob Herring	depends on !ARCH_MULTIPLATFORM
651855c551fSCatalin Marinas	help
652855c551fSCatalin Marinas	  This option enables the workaround for the 458693 Cortex-A8 (r2p0)
653855c551fSCatalin Marinas	  erratum. For very specific sequences of memory operations, it is
654855c551fSCatalin Marinas	  possible for a hazard condition intended for a cache line to instead
655855c551fSCatalin Marinas	  be incorrectly associated with a different cache line. This false
656855c551fSCatalin Marinas	  hazard might then cause a processor deadlock. The workaround enables
657855c551fSCatalin Marinas	  the L1 caching of the NEON accesses and disables the PLD instruction
658855c551fSCatalin Marinas	  in the ACTLR register. Note that setting specific bits in the ACTLR
659368ccecdSSebastian Reichel	  register may not be available in non-secure mode and thus is not
660368ccecdSSebastian Reichel	  available on a multiplatform kernel. This should be applied by the
661368ccecdSSebastian Reichel	  bootloader instead.
662855c551fSCatalin Marinas
6630516e464SCatalin Marinasconfig ARM_ERRATA_460075
6640516e464SCatalin Marinas	bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
6650516e464SCatalin Marinas	depends on CPU_V7
66662e4d357SRob Herring	depends on !ARCH_MULTIPLATFORM
6670516e464SCatalin Marinas	help
6680516e464SCatalin Marinas	  This option enables the workaround for the 460075 Cortex-A8 (r2p0)
6690516e464SCatalin Marinas	  erratum. Any asynchronous access to the L2 cache may encounter a
6700516e464SCatalin Marinas	  situation in which recent store transactions to the L2 cache are lost
6710516e464SCatalin Marinas	  and overwritten with stale memory contents from external memory. The
6720516e464SCatalin Marinas	  workaround disables the write-allocate mode for the L2 cache via the
6730516e464SCatalin Marinas	  ACTLR register. Note that setting specific bits in the ACTLR register
674368ccecdSSebastian Reichel	  may not be available in non-secure mode and thus is not available on
675368ccecdSSebastian Reichel	  a multiplatform kernel. This should be applied by the bootloader
676368ccecdSSebastian Reichel	  instead.
6770516e464SCatalin Marinas
6789f05027cSWill Deaconconfig ARM_ERRATA_742230
6799f05027cSWill Deacon	bool "ARM errata: DMB operation may be faulty"
6809f05027cSWill Deacon	depends on CPU_V7 && SMP
68162e4d357SRob Herring	depends on !ARCH_MULTIPLATFORM
6829f05027cSWill Deacon	help
6839f05027cSWill Deacon	  This option enables the workaround for the 742230 Cortex-A9
6849f05027cSWill Deacon	  (r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction
6859f05027cSWill Deacon	  between two write operations may not ensure the correct visibility
6869f05027cSWill Deacon	  ordering of the two writes. This workaround sets a specific bit in
6879f05027cSWill Deacon	  the diagnostic register of the Cortex-A9 which causes the DMB
6889f05027cSWill Deacon	  instruction to behave as a DSB, ensuring the correct behaviour of
689368ccecdSSebastian Reichel	  the two writes. Note that setting specific bits in the diagnostics
690368ccecdSSebastian Reichel	  register may not be available in non-secure mode and thus is not
691368ccecdSSebastian Reichel	  available on a multiplatform kernel. This should be applied by the
692368ccecdSSebastian Reichel	  bootloader instead.
6939f05027cSWill Deacon
694a672e99bSWill Deaconconfig ARM_ERRATA_742231
695a672e99bSWill Deacon	bool "ARM errata: Incorrect hazard handling in the SCU may lead to data corruption"
696a672e99bSWill Deacon	depends on CPU_V7 && SMP
69762e4d357SRob Herring	depends on !ARCH_MULTIPLATFORM
698a672e99bSWill Deacon	help
699a672e99bSWill Deacon	  This option enables the workaround for the 742231 Cortex-A9
700a672e99bSWill Deacon	  (r2p0..r2p2) erratum. Under certain conditions, specific to the
701a672e99bSWill Deacon	  Cortex-A9 MPCore micro-architecture, two CPUs working in SMP mode,
702a672e99bSWill Deacon	  accessing some data located in the same cache line, may get corrupted
703a672e99bSWill Deacon	  data due to bad handling of the address hazard when the line gets
704a672e99bSWill Deacon	  replaced from one of the CPUs at the same time as another CPU is
705a672e99bSWill Deacon	  accessing it. This workaround sets specific bits in the diagnostic
706a672e99bSWill Deacon	  register of the Cortex-A9 which reduces the linefill issuing
707368ccecdSSebastian Reichel	  capabilities of the processor. Note that setting specific bits in the
708368ccecdSSebastian Reichel	  diagnostics register may not be available in non-secure mode and thus
709368ccecdSSebastian Reichel	  is not available on a multiplatform kernel. This should be applied by
710368ccecdSSebastian Reichel	  the bootloader instead.
711a672e99bSWill Deacon
71269155794SJon Medhurstconfig ARM_ERRATA_643719
71369155794SJon Medhurst	bool "ARM errata: LoUIS bit field in CLIDR register is incorrect"
71469155794SJon Medhurst	depends on CPU_V7 && SMP
715e5a5de44SRussell King	default y
71669155794SJon Medhurst	help
71769155794SJon Medhurst	  This option enables the workaround for the 643719 Cortex-A9 (prior to
71869155794SJon Medhurst	  r1p0) erratum. On affected cores the LoUIS bit field of the CLIDR
71969155794SJon Medhurst	  register returns zero when it should return one. The workaround
72069155794SJon Medhurst	  corrects this value, ensuring cache maintenance operations which use
72169155794SJon Medhurst	  it behave as intended and avoiding data corruption.
72269155794SJon Medhurst
723cdf357f1SWill Deaconconfig ARM_ERRATA_720789
724cdf357f1SWill Deacon	bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID"
725e66dc745SDave Martin	depends on CPU_V7
726cdf357f1SWill Deacon	help
727cdf357f1SWill Deacon	  This option enables the workaround for the 720789 Cortex-A9 (prior to
728cdf357f1SWill Deacon	  r2p0) erratum. A faulty ASID can be sent to the other CPUs for the
729cdf357f1SWill Deacon	  broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS.
730cdf357f1SWill Deacon	  As a consequence of this erratum, some TLB entries which should be
731cdf357f1SWill Deacon	  invalidated are not, resulting in an incoherency in the system page
732cdf357f1SWill Deacon	  tables. The workaround changes the TLB flushing routines to invalidate
733cdf357f1SWill Deacon	  entries regardless of the ASID.
734475d92fcSWill Deacon
735475d92fcSWill Deaconconfig ARM_ERRATA_743622
736475d92fcSWill Deacon	bool "ARM errata: Faulty hazard checking in the Store Buffer may lead to data corruption"
737475d92fcSWill Deacon	depends on CPU_V7
73862e4d357SRob Herring	depends on !ARCH_MULTIPLATFORM
739475d92fcSWill Deacon	help
740475d92fcSWill Deacon	  This option enables the workaround for the 743622 Cortex-A9
741efbc74acSWill Deacon	  (r2p*) erratum. Under very rare conditions, a faulty
742475d92fcSWill Deacon	  optimisation in the Cortex-A9 Store Buffer may lead to data
743475d92fcSWill Deacon	  corruption. This workaround sets a specific bit in the diagnostic
744475d92fcSWill Deacon	  register of the Cortex-A9 which disables the Store Buffer
745475d92fcSWill Deacon	  optimisation, preventing the defect from occurring. This has no
746475d92fcSWill Deacon	  visible impact on the overall performance or power consumption of the
747368ccecdSSebastian Reichel	  processor. Note that setting specific bits in the diagnostics register
748368ccecdSSebastian Reichel	  may not be available in non-secure mode and thus is not available on a
749368ccecdSSebastian Reichel	  multiplatform kernel. This should be applied by the bootloader instead.
750475d92fcSWill Deacon
7519a27c27cSWill Deaconconfig ARM_ERRATA_751472
7529a27c27cSWill Deacon	bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation"
753ba90c516SDave Martin	depends on CPU_V7
75462e4d357SRob Herring	depends on !ARCH_MULTIPLATFORM
7559a27c27cSWill Deacon	help
7569a27c27cSWill Deacon	  This option enables the workaround for the 751472 Cortex-A9 (prior
7579a27c27cSWill Deacon	  to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the
7589a27c27cSWill Deacon	  completion of a following broadcasted operation if the second
7599a27c27cSWill Deacon	  operation is received by a CPU before the ICIALLUIS has completed,
7609a27c27cSWill Deacon	  potentially leading to corrupted entries in the cache or TLB.
761368ccecdSSebastian Reichel	  Note that setting specific bits in the diagnostics register may
762368ccecdSSebastian Reichel	  not be available in non-secure mode and thus is not available on
763368ccecdSSebastian Reichel	  a multiplatform kernel. This should be applied by the bootloader
764368ccecdSSebastian Reichel	  instead.
7659a27c27cSWill Deacon
766fcbdc5feSWill Deaconconfig ARM_ERRATA_754322
767fcbdc5feSWill Deacon	bool "ARM errata: possible faulty MMU translations following an ASID switch"
768fcbdc5feSWill Deacon	depends on CPU_V7
769fcbdc5feSWill Deacon	help
770fcbdc5feSWill Deacon	  This option enables the workaround for the 754322 Cortex-A9 (r2p*,
771fcbdc5feSWill Deacon	  r3p*) erratum. A speculative memory access may cause a page table walk
772fcbdc5feSWill Deacon	  which starts prior to an ASID switch but completes afterwards. This
773fcbdc5feSWill Deacon	  can populate the micro-TLB with a stale entry which may be hit with
774fcbdc5feSWill Deacon	  the new ASID. This workaround places two dsb instructions in the mm
775fcbdc5feSWill Deacon	  switching code so that no page table walks can cross the ASID switch.
776fcbdc5feSWill Deacon
7775dab26afSWill Deaconconfig ARM_ERRATA_754327
7785dab26afSWill Deacon	bool "ARM errata: no automatic Store Buffer drain"
7795dab26afSWill Deacon	depends on CPU_V7 && SMP
7805dab26afSWill Deacon	help
7815dab26afSWill Deacon	  This option enables the workaround for the 754327 Cortex-A9 (prior to
7825dab26afSWill Deacon	  r2p0) erratum. The Store Buffer does not have any automatic draining
7835dab26afSWill Deacon	  mechanism and therefore a livelock may occur if an external agent
7845dab26afSWill Deacon	  continuously polls a memory location waiting to observe an update.
7855dab26afSWill Deacon	  This workaround defines cpu_relax() as smp_mb(), preventing correctly
7865dab26afSWill Deacon	  written polling loops from denying visibility of updates to memory.
7875dab26afSWill Deacon
788145e10e1SCatalin Marinasconfig ARM_ERRATA_364296
789145e10e1SCatalin Marinas	bool "ARM errata: Possible cache data corruption with hit-under-miss enabled"
790fd832478SFabio Estevam	depends on CPU_V6
791145e10e1SCatalin Marinas	help
792145e10e1SCatalin Marinas	  This options enables the workaround for the 364296 ARM1136
793145e10e1SCatalin Marinas	  r0p2 erratum (possible cache data corruption with
794145e10e1SCatalin Marinas	  hit-under-miss enabled). It sets the undocumented bit 31 in
795145e10e1SCatalin Marinas	  the auxiliary control register and the FI bit in the control
796145e10e1SCatalin Marinas	  register, thus disabling hit-under-miss without putting the
797145e10e1SCatalin Marinas	  processor into full low interrupt latency mode. ARM11MPCore
798145e10e1SCatalin Marinas	  is not affected.
799145e10e1SCatalin Marinas
800f630c1bdSWill Deaconconfig ARM_ERRATA_764369
801f630c1bdSWill Deacon	bool "ARM errata: Data cache line maintenance operation by MVA may not succeed"
802f630c1bdSWill Deacon	depends on CPU_V7 && SMP
803f630c1bdSWill Deacon	help
804f630c1bdSWill Deacon	  This option enables the workaround for erratum 764369
805f630c1bdSWill Deacon	  affecting Cortex-A9 MPCore with two or more processors (all
806f630c1bdSWill Deacon	  current revisions). Under certain timing circumstances, a data
807f630c1bdSWill Deacon	  cache line maintenance operation by MVA targeting an Inner
808f630c1bdSWill Deacon	  Shareable memory region may fail to proceed up to either the
809f630c1bdSWill Deacon	  Point of Coherency or to the Point of Unification of the
810f630c1bdSWill Deacon	  system. This workaround adds a DSB instruction before the
811f630c1bdSWill Deacon	  relevant cache maintenance functions and sets a specific bit
812f630c1bdSWill Deacon	  in the diagnostic control register of the SCU.
813f630c1bdSWill Deacon
8148294fec1SNick Hawkinsconfig ARM_ERRATA_764319
8158294fec1SNick Hawkins	bool "ARM errata: Read to DBGPRSR and DBGOSLSR may generate Undefined instruction"
8168294fec1SNick Hawkins	depends on CPU_V7
8178294fec1SNick Hawkins	help
8188294fec1SNick Hawkins	  This option enables the workaround for the 764319 Cortex A-9 erratum.
8198294fec1SNick Hawkins	  CP14 read accesses to the DBGPRSR and DBGOSLSR registers generate an
8208294fec1SNick Hawkins	  unexpected Undefined Instruction exception when the DBGSWENABLE
8218294fec1SNick Hawkins	  external pin is set to 0, even when the CP14 accesses are performed
8228294fec1SNick Hawkins	  from a privileged mode. This work around catches the exception in a
8238294fec1SNick Hawkins	  way the kernel does not stop execution.
8248294fec1SNick Hawkins
8257253b85cSSimon Hormanconfig ARM_ERRATA_775420
8267253b85cSSimon Horman       bool "ARM errata: A data cache maintenance operation which aborts, might lead to deadlock"
8277253b85cSSimon Horman       depends on CPU_V7
8287253b85cSSimon Horman       help
8297253b85cSSimon Horman	 This option enables the workaround for the 775420 Cortex-A9 (r2p2,
830cb73737eSGeert Uytterhoeven	 r2p6,r2p8,r2p10,r3p0) erratum. In case a data cache maintenance
8317253b85cSSimon Horman	 operation aborts with MMU exception, it might cause the processor
8327253b85cSSimon Horman	 to deadlock. This workaround puts DSB before executing ISB if
8337253b85cSSimon Horman	 an abort may occur on cache maintenance.
8347253b85cSSimon Horman
83593dc6887SCatalin Marinasconfig ARM_ERRATA_798181
83693dc6887SCatalin Marinas	bool "ARM errata: TLBI/DSB failure on Cortex-A15"
83793dc6887SCatalin Marinas	depends on CPU_V7 && SMP
83893dc6887SCatalin Marinas	help
83993dc6887SCatalin Marinas	  On Cortex-A15 (r0p0..r3p2) the TLBI*IS/DSB operations are not
84093dc6887SCatalin Marinas	  adequately shooting down all use of the old entries. This
84193dc6887SCatalin Marinas	  option enables the Linux kernel workaround for this erratum
84293dc6887SCatalin Marinas	  which sends an IPI to the CPUs that are running the same ASID
84393dc6887SCatalin Marinas	  as the one being invalidated.
84493dc6887SCatalin Marinas
84584b6504fSWill Deaconconfig ARM_ERRATA_773022
84684b6504fSWill Deacon	bool "ARM errata: incorrect instructions may be executed from loop buffer"
84784b6504fSWill Deacon	depends on CPU_V7
84884b6504fSWill Deacon	help
84984b6504fSWill Deacon	  This option enables the workaround for the 773022 Cortex-A15
85084b6504fSWill Deacon	  (up to r0p4) erratum. In certain rare sequences of code, the
85184b6504fSWill Deacon	  loop buffer may deliver incorrect instructions. This
85284b6504fSWill Deacon	  workaround disables the loop buffer to avoid the erratum.
85384b6504fSWill Deacon
85462c0f4a5SDoug Andersonconfig ARM_ERRATA_818325_852422
85562c0f4a5SDoug Anderson	bool "ARM errata: A12: some seqs of opposed cond code instrs => deadlock or corruption"
85662c0f4a5SDoug Anderson	depends on CPU_V7
85762c0f4a5SDoug Anderson	help
85862c0f4a5SDoug Anderson	  This option enables the workaround for:
85962c0f4a5SDoug Anderson	  - Cortex-A12 818325: Execution of an UNPREDICTABLE STR or STM
86062c0f4a5SDoug Anderson	    instruction might deadlock.  Fixed in r0p1.
86162c0f4a5SDoug Anderson	  - Cortex-A12 852422: Execution of a sequence of instructions might
86262c0f4a5SDoug Anderson	    lead to either a data corruption or a CPU deadlock.  Not fixed in
86362c0f4a5SDoug Anderson	    any Cortex-A12 cores yet.
86462c0f4a5SDoug Anderson	  This workaround for all both errata involves setting bit[12] of the
86562c0f4a5SDoug Anderson	  Feature Register. This bit disables an optimisation applied to a
86662c0f4a5SDoug Anderson	  sequence of 2 instructions that use opposing condition codes.
86762c0f4a5SDoug Anderson
868416bcf21SDoug Andersonconfig ARM_ERRATA_821420
869416bcf21SDoug Anderson	bool "ARM errata: A12: sequence of VMOV to core registers might lead to a dead lock"
870416bcf21SDoug Anderson	depends on CPU_V7
871416bcf21SDoug Anderson	help
872416bcf21SDoug Anderson	  This option enables the workaround for the 821420 Cortex-A12
873416bcf21SDoug Anderson	  (all revs) erratum. In very rare timing conditions, a sequence
874416bcf21SDoug Anderson	  of VMOV to Core registers instructions, for which the second
875416bcf21SDoug Anderson	  one is in the shadow of a branch or abort, can lead to a
876416bcf21SDoug Anderson	  deadlock when the VMOV instructions are issued out-of-order.
877416bcf21SDoug Anderson
8789f6f9354SDoug Andersonconfig ARM_ERRATA_825619
8799f6f9354SDoug Anderson	bool "ARM errata: A12: DMB NSHST/ISHST mixed ... might cause deadlock"
8809f6f9354SDoug Anderson	depends on CPU_V7
8819f6f9354SDoug Anderson	help
8829f6f9354SDoug Anderson	  This option enables the workaround for the 825619 Cortex-A12
8839f6f9354SDoug Anderson	  (all revs) erratum. Within rare timing constraints, executing a
8849f6f9354SDoug Anderson	  DMB NSHST or DMB ISHST instruction followed by a mix of Cacheable
8859f6f9354SDoug Anderson	  and Device/Strongly-Ordered loads and stores might cause deadlock
8869f6f9354SDoug Anderson
887304009a1SDoug Andersonconfig ARM_ERRATA_857271
888304009a1SDoug Anderson	bool "ARM errata: A12: CPU might deadlock under some very rare internal conditions"
889304009a1SDoug Anderson	depends on CPU_V7
890304009a1SDoug Anderson	help
891304009a1SDoug Anderson	  This option enables the workaround for the 857271 Cortex-A12
892304009a1SDoug Anderson	  (all revs) erratum. Under very rare timing conditions, the CPU might
893304009a1SDoug Anderson	  hang. The workaround is expected to have a < 1% performance impact.
894304009a1SDoug Anderson
8959f6f9354SDoug Andersonconfig ARM_ERRATA_852421
8969f6f9354SDoug Anderson	bool "ARM errata: A17: DMB ST might fail to create order between stores"
8979f6f9354SDoug Anderson	depends on CPU_V7
8989f6f9354SDoug Anderson	help
8999f6f9354SDoug Anderson	  This option enables the workaround for the 852421 Cortex-A17
9009f6f9354SDoug Anderson	  (r1p0, r1p1, r1p2) erratum. Under very rare timing conditions,
9019f6f9354SDoug Anderson	  execution of a DMB ST instruction might fail to properly order
9029f6f9354SDoug Anderson	  stores from GroupA and stores from GroupB.
9039f6f9354SDoug Anderson
90462c0f4a5SDoug Andersonconfig ARM_ERRATA_852423
90562c0f4a5SDoug Anderson	bool "ARM errata: A17: some seqs of opposed cond code instrs => deadlock or corruption"
90662c0f4a5SDoug Anderson	depends on CPU_V7
90762c0f4a5SDoug Anderson	help
90862c0f4a5SDoug Anderson	  This option enables the workaround for:
90962c0f4a5SDoug Anderson	  - Cortex-A17 852423: Execution of a sequence of instructions might
91062c0f4a5SDoug Anderson	    lead to either a data corruption or a CPU deadlock.  Not fixed in
91162c0f4a5SDoug Anderson	    any Cortex-A17 cores yet.
91262c0f4a5SDoug Anderson	  This is identical to Cortex-A12 erratum 852422.  It is a separate
91362c0f4a5SDoug Anderson	  config option from the A12 erratum due to the way errata are checked
91462c0f4a5SDoug Anderson	  for and handled.
91562c0f4a5SDoug Anderson
916304009a1SDoug Andersonconfig ARM_ERRATA_857272
917304009a1SDoug Anderson	bool "ARM errata: A17: CPU might deadlock under some very rare internal conditions"
918304009a1SDoug Anderson	depends on CPU_V7
919304009a1SDoug Anderson	help
920304009a1SDoug Anderson	  This option enables the workaround for the 857272 Cortex-A17 erratum.
921304009a1SDoug Anderson	  This erratum is not known to be fixed in any A17 revision.
922304009a1SDoug Anderson	  This is identical to Cortex-A12 erratum 857271.  It is a separate
923304009a1SDoug Anderson	  config option from the A12 erratum due to the way errata are checked
924304009a1SDoug Anderson	  for and handled.
925304009a1SDoug Anderson
9261da177e4SLinus Torvaldsendmenu
9271da177e4SLinus Torvalds
9281da177e4SLinus Torvaldssource "arch/arm/common/Kconfig"
9291da177e4SLinus Torvalds
9301da177e4SLinus Torvaldsmenu "Bus support"
9311da177e4SLinus Torvalds
9321da177e4SLinus Torvaldsconfig ISA
9331da177e4SLinus Torvalds	bool
9341da177e4SLinus Torvalds	help
9351da177e4SLinus Torvalds	  Find out whether you have ISA slots on your motherboard.  ISA is the
9361da177e4SLinus Torvalds	  name of a bus system, i.e. the way the CPU talks to the other stuff
9371da177e4SLinus Torvalds	  inside your box.  Other bus systems are PCI, EISA, MicroChannel
9381da177e4SLinus Torvalds	  (MCA) or VESA.  ISA is an older system, now being displaced by PCI;
9391da177e4SLinus Torvalds	  newer boards don't support it.  If you have ISA, say Y, otherwise N.
9401da177e4SLinus Torvalds
941065909b9SRussell King# Select ISA DMA interface
9425cae841bSAl Viroconfig ISA_DMA_API
9435cae841bSAl Viro	bool
9445cae841bSAl Viro
945779eb41cSBenjamin Gaignardconfig ARM_ERRATA_814220
946779eb41cSBenjamin Gaignard	bool "ARM errata: Cache maintenance by set/way operations can execute out of order"
947779eb41cSBenjamin Gaignard	depends on CPU_V7
948779eb41cSBenjamin Gaignard	help
949779eb41cSBenjamin Gaignard	  The v7 ARM states that all cache and branch predictor maintenance
950779eb41cSBenjamin Gaignard	  operations that do not specify an address execute, relative to
951779eb41cSBenjamin Gaignard	  each other, in program order.
952779eb41cSBenjamin Gaignard	  However, because of this erratum, an L2 set/way cache maintenance
953779eb41cSBenjamin Gaignard	  operation can overtake an L1 set/way cache maintenance operation.
954779eb41cSBenjamin Gaignard	  This ERRATA only affected the Cortex-A7 and present in r0p2, r0p3,
955779eb41cSBenjamin Gaignard	  r0p4, r0p5.
956779eb41cSBenjamin Gaignard
9571da177e4SLinus Torvaldsendmenu
9581da177e4SLinus Torvalds
9591da177e4SLinus Torvaldsmenu "Kernel Features"
9601da177e4SLinus Torvalds
9613b55658aSDave Martinconfig HAVE_SMP
9623b55658aSDave Martin	bool
9633b55658aSDave Martin	help
9643b55658aSDave Martin	  This option should be selected by machines which have an SMP-
9653b55658aSDave Martin	  capable CPU.
9663b55658aSDave Martin
9673b55658aSDave Martin	  The only effect of this option is to make the SMP-related
9683b55658aSDave Martin	  options available to the user for configuration.
9693b55658aSDave Martin
9701da177e4SLinus Torvaldsconfig SMP
971bb2d8130SRussell King	bool "Symmetric Multi-Processing"
972fbb4ddacSRussell King	depends on CPU_V6K || CPU_V7
9733b55658aSDave Martin	depends on HAVE_SMP
974801bb21cSJonathan Austin	depends on MMU || ARM_MPU
9750361748fSArnd Bergmann	select IRQ_WORK
9761da177e4SLinus Torvalds	help
9771da177e4SLinus Torvalds	  This enables support for systems with more than one CPU. If you have
9784a474157SRobert Graffham	  a system with only one CPU, say N. If you have a system with more
9794a474157SRobert Graffham	  than one CPU, say Y.
9801da177e4SLinus Torvalds
9814a474157SRobert Graffham	  If you say N here, the kernel will run on uni- and multiprocessor
9821da177e4SLinus Torvalds	  machines, but will use only one CPU of a multiprocessor machine. If
9834a474157SRobert Graffham	  you say Y here, the kernel will run on many, but not all,
9844a474157SRobert Graffham	  uniprocessor machines. On a uniprocessor machine, the kernel
9854a474157SRobert Graffham	  will run faster if you say N here.
9861da177e4SLinus Torvalds
987ff61f079SJonathan Corbet	  See also <file:Documentation/arch/x86/i386/IO-APIC.rst>,
9884f4cfa6cSMauro Carvalho Chehab	  <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at
98950a23e6eSJustin P. Mattock	  <http://tldp.org/HOWTO/SMP-HOWTO.html>.
9901da177e4SLinus Torvalds
9911da177e4SLinus Torvalds	  If you don't know what to do here, say N.
9921da177e4SLinus Torvalds
993f00ec48fSRussell Kingconfig SMP_ON_UP
9945744ff43SRussell King	bool "Allow booting SMP kernel on uniprocessor systems"
9955408445bSArnd Bergmann	depends on SMP && MMU
996f00ec48fSRussell King	default y
997f00ec48fSRussell King	help
998f00ec48fSRussell King	  SMP kernels contain instructions which fail on non-SMP processors.
999f00ec48fSRussell King	  Enabling this option allows the kernel to modify itself to make
1000f00ec48fSRussell King	  these instructions safe.  Disabling it allows about 1K of space
1001f00ec48fSRussell King	  savings.
1002f00ec48fSRussell King
1003f00ec48fSRussell King	  If you don't know what to do here, say Y.
1004f00ec48fSRussell King
100550596b75SArd Biesheuvel
100650596b75SArd Biesheuvelconfig CURRENT_POINTER_IN_TPIDRURO
100750596b75SArd Biesheuvel	def_bool y
1008b87cf911SArd Biesheuvel	depends on CPU_32v6K && !CPU_V6
100950596b75SArd Biesheuvel
1010d4664b6cSArd Biesheuvelconfig IRQSTACKS
1011d4664b6cSArd Biesheuvel	def_bool y
10129974f857SArd Biesheuvel	select HAVE_IRQ_EXIT_ON_IRQ_STACK
10139974f857SArd Biesheuvel	select HAVE_SOFTIRQ_ON_OWN_STACK
10141da177e4SLinus Torvalds
1015c9018aabSVincent Guittotconfig ARM_CPU_TOPOLOGY
1016c9018aabSVincent Guittot	bool "Support cpu topology definition"
1017c9018aabSVincent Guittot	depends on SMP && CPU_V7
1018c9018aabSVincent Guittot	default y
1019c9018aabSVincent Guittot	help
1020c9018aabSVincent Guittot	  Support ARM cpu topology definition. The MPIDR register defines
1021c9018aabSVincent Guittot	  affinity between processors which is then used to describe the cpu
1022c9018aabSVincent Guittot	  topology of an ARM System.
1023c9018aabSVincent Guittot
1024c9018aabSVincent Guittotconfig SCHED_MC
1025c9018aabSVincent Guittot	bool "Multi-core scheduler support"
1026c9018aabSVincent Guittot	depends on ARM_CPU_TOPOLOGY
1027c9018aabSVincent Guittot	help
1028c9018aabSVincent Guittot	  Multi-core scheduler support improves the CPU scheduler's decision
1029c9018aabSVincent Guittot	  making when dealing with multi-core CPU chips at a cost of slightly
1030c9018aabSVincent Guittot	  increased overhead in some places. If unsure say N here.
1031c9018aabSVincent Guittot
1032c9018aabSVincent Guittotconfig SCHED_SMT
1033c9018aabSVincent Guittot	bool "SMT scheduler support"
1034c9018aabSVincent Guittot	depends on ARM_CPU_TOPOLOGY
1035c9018aabSVincent Guittot	help
1036c9018aabSVincent Guittot	  Improves the CPU scheduler's decision making when dealing with
1037c9018aabSVincent Guittot	  MultiThreading at a cost of slightly increased overhead in some
1038c9018aabSVincent Guittot	  places. If unsure say N here.
1039c9018aabSVincent Guittot
1040a8cbcd92SRussell Kingconfig HAVE_ARM_SCU
1041a8cbcd92SRussell King	bool
1042a8cbcd92SRussell King	help
10438f433ec4SGeert Uytterhoeven	  This option enables support for the ARM snoop control unit
1044a8cbcd92SRussell King
10458a4da6e3SMark Rutlandconfig HAVE_ARM_ARCH_TIMER
1046022c03a2SMarc Zyngier	bool "Architected timer support"
1047022c03a2SMarc Zyngier	depends on CPU_V7
10488a4da6e3SMark Rutland	select ARM_ARCH_TIMER
1049022c03a2SMarc Zyngier	help
1050022c03a2SMarc Zyngier	  This option enables support for the ARM architected timer
1051022c03a2SMarc Zyngier
1052f32f4ce2SRussell Kingconfig HAVE_ARM_TWD
1053f32f4ce2SRussell King	bool
1054f32f4ce2SRussell King	help
1055f32f4ce2SRussell King	  This options enables support for the ARM timer and watchdog unit
1056f32f4ce2SRussell King
1057e8db288eSNicolas Pitreconfig MCPM
1058e8db288eSNicolas Pitre	bool "Multi-Cluster Power Management"
1059e8db288eSNicolas Pitre	depends on CPU_V7 && SMP
1060e8db288eSNicolas Pitre	help
1061e8db288eSNicolas Pitre	  This option provides the common power management infrastructure
1062e8db288eSNicolas Pitre	  for (multi-)cluster based systems, such as big.LITTLE based
1063e8db288eSNicolas Pitre	  systems.
1064e8db288eSNicolas Pitre
1065ebf4a5c5SHaojian Zhuangconfig MCPM_QUAD_CLUSTER
1066ebf4a5c5SHaojian Zhuang	bool
1067ebf4a5c5SHaojian Zhuang	depends on MCPM
1068ebf4a5c5SHaojian Zhuang	help
1069ebf4a5c5SHaojian Zhuang	  To avoid wasting resources unnecessarily, MCPM only supports up
1070ebf4a5c5SHaojian Zhuang	  to 2 clusters by default.
1071ebf4a5c5SHaojian Zhuang	  Platforms with 3 or 4 clusters that use MCPM must select this
1072ebf4a5c5SHaojian Zhuang	  option to allow the additional clusters to be managed.
1073ebf4a5c5SHaojian Zhuang
10741c33be57SNicolas Pitreconfig BIG_LITTLE
10751c33be57SNicolas Pitre	bool "big.LITTLE support (Experimental)"
10761c33be57SNicolas Pitre	depends on CPU_V7 && SMP
10771c33be57SNicolas Pitre	select MCPM
10781c33be57SNicolas Pitre	help
10791c33be57SNicolas Pitre	  This option enables support selections for the big.LITTLE
10801c33be57SNicolas Pitre	  system architecture.
10811c33be57SNicolas Pitre
10821c33be57SNicolas Pitreconfig BL_SWITCHER
10831c33be57SNicolas Pitre	bool "big.LITTLE switcher support"
10846c044fecSArnd Bergmann	depends on BIG_LITTLE && MCPM && HOTPLUG_CPU && ARM_GIC
108551aaf81fSRussell King	select CPU_PM
10861c33be57SNicolas Pitre	help
10871c33be57SNicolas Pitre	  The big.LITTLE "switcher" provides the core functionality to
10881c33be57SNicolas Pitre	  transparently handle transition between a cluster of A15's
10891c33be57SNicolas Pitre	  and a cluster of A7's in a big.LITTLE system.
10901c33be57SNicolas Pitre
1091b22537c6SNicolas Pitreconfig BL_SWITCHER_DUMMY_IF
1092b22537c6SNicolas Pitre	tristate "Simple big.LITTLE switcher user interface"
1093b22537c6SNicolas Pitre	depends on BL_SWITCHER && DEBUG_KERNEL
1094b22537c6SNicolas Pitre	help
1095b22537c6SNicolas Pitre	  This is a simple and dummy char dev interface to control
1096b22537c6SNicolas Pitre	  the big.LITTLE switcher core code.  It is meant for
1097b22537c6SNicolas Pitre	  debugging purposes only.
1098b22537c6SNicolas Pitre
10998d5796d2SLennert Buytenhekchoice
11008d5796d2SLennert Buytenhek	prompt "Memory split"
1101006fa259SRussell King	depends on MMU
11028d5796d2SLennert Buytenhek	default VMSPLIT_3G
11038d5796d2SLennert Buytenhek	help
11048d5796d2SLennert Buytenhek	  Select the desired split between kernel and user memory.
11058d5796d2SLennert Buytenhek
11068d5796d2SLennert Buytenhek	  If you are not absolutely sure what you are doing, leave this
11078d5796d2SLennert Buytenhek	  option alone!
11088d5796d2SLennert Buytenhek
11098d5796d2SLennert Buytenhek	config VMSPLIT_3G
11108d5796d2SLennert Buytenhek		bool "3G/1G user/kernel split"
111163ce446cSNicolas Pitre	config VMSPLIT_3G_OPT
1112bbeedfdaSYisheng Xie		depends on !ARM_LPAE
111363ce446cSNicolas Pitre		bool "3G/1G user/kernel split (for full 1G low memory)"
11148d5796d2SLennert Buytenhek	config VMSPLIT_2G
11158d5796d2SLennert Buytenhek		bool "2G/2G user/kernel split"
11168d5796d2SLennert Buytenhek	config VMSPLIT_1G
11178d5796d2SLennert Buytenhek		bool "1G/3G user/kernel split"
11188d5796d2SLennert Buytenhekendchoice
11198d5796d2SLennert Buytenhek
11208d5796d2SLennert Buytenhekconfig PAGE_OFFSET
11218d5796d2SLennert Buytenhek	hex
1122006fa259SRussell King	default PHYS_OFFSET if !MMU
11238d5796d2SLennert Buytenhek	default 0x40000000 if VMSPLIT_1G
11248d5796d2SLennert Buytenhek	default 0x80000000 if VMSPLIT_2G
112563ce446cSNicolas Pitre	default 0xB0000000 if VMSPLIT_3G_OPT
11268d5796d2SLennert Buytenhek	default 0xC0000000
11278d5796d2SLennert Buytenhek
1128c12366baSLinus Walleijconfig KASAN_SHADOW_OFFSET
1129c12366baSLinus Walleij	hex
1130c12366baSLinus Walleij	depends on KASAN
1131c12366baSLinus Walleij	default 0x1f000000 if PAGE_OFFSET=0x40000000
1132c12366baSLinus Walleij	default 0x5f000000 if PAGE_OFFSET=0x80000000
1133c12366baSLinus Walleij	default 0x9f000000 if PAGE_OFFSET=0xC0000000
1134c12366baSLinus Walleij	default 0x8f000000 if PAGE_OFFSET=0xB0000000
1135c12366baSLinus Walleij	default 0xffffffff
1136c12366baSLinus Walleij
11371da177e4SLinus Torvaldsconfig NR_CPUS
11381da177e4SLinus Torvalds	int "Maximum number of CPUs (2-32)"
1139d624833fSArd Biesheuvel	range 2 16 if DEBUG_KMAP_LOCAL
1140d624833fSArd Biesheuvel	range 2 32 if !DEBUG_KMAP_LOCAL
11411da177e4SLinus Torvalds	depends on SMP
11421da177e4SLinus Torvalds	default "4"
1143d624833fSArd Biesheuvel	help
1144d624833fSArd Biesheuvel	  The maximum number of CPUs that the kernel can support.
1145d624833fSArd Biesheuvel	  Up to 32 CPUs can be supported, or up to 16 if kmap_local()
1146d624833fSArd Biesheuvel	  debugging is enabled, which uses half of the per-CPU fixmap
1147d624833fSArd Biesheuvel	  slots as guard regions.
11481da177e4SLinus Torvalds
1149a054a811SRussell Kingconfig HOTPLUG_CPU
115000b7dedeSRussell King	bool "Support for hot-pluggable CPUs"
115140b31360SStephen Rothwell	depends on SMP
11521b5ba350SDietmar Eggemann	select GENERIC_IRQ_MIGRATION
1153a054a811SRussell King	help
1154a054a811SRussell King	  Say Y here to experiment with turning CPUs off and on.  CPUs
1155a054a811SRussell King	  can be controlled through /sys/devices/system/cpu.
1156a054a811SRussell King
11572bdd424fSWill Deaconconfig ARM_PSCI
11582bdd424fSWill Deacon	bool "Support for the ARM Power State Coordination Interface (PSCI)"
1159e679660dSJens Wiklander	depends on HAVE_ARM_SMCCC
1160be120397SMark Rutland	select ARM_PSCI_FW
11612bdd424fSWill Deacon	help
11622bdd424fSWill Deacon	  Say Y here if you want Linux to communicate with system firmware
11632bdd424fSWill Deacon	  implementing the PSCI specification for CPU-centric power
11642bdd424fSWill Deacon	  management operations described in ARM document number ARM DEN
11652bdd424fSWill Deacon	  0022A ("Power State Coordination Interface System Software on
11662bdd424fSWill Deacon	  ARM processors").
11672bdd424fSWill Deacon
1168c9218b16SRussell Kingconfig HZ_FIXED
1169f8065813SRussell King	int
11701164f672SAlexandre Belloni	default 128 if SOC_AT91RM9200
117147d84682SRussell King	default 0
1172c9218b16SRussell King
1173c9218b16SRussell Kingchoice
117447d84682SRussell King	depends on HZ_FIXED = 0
1175c9218b16SRussell King	prompt "Timer frequency"
1176c9218b16SRussell King
1177c9218b16SRussell Kingconfig HZ_100
1178c9218b16SRussell King	bool "100 Hz"
1179c9218b16SRussell King
1180c9218b16SRussell Kingconfig HZ_200
1181c9218b16SRussell King	bool "200 Hz"
1182c9218b16SRussell King
1183c9218b16SRussell Kingconfig HZ_250
1184c9218b16SRussell King	bool "250 Hz"
1185c9218b16SRussell King
1186c9218b16SRussell Kingconfig HZ_300
1187c9218b16SRussell King	bool "300 Hz"
1188c9218b16SRussell King
1189c9218b16SRussell Kingconfig HZ_500
1190c9218b16SRussell King	bool "500 Hz"
1191c9218b16SRussell King
1192c9218b16SRussell Kingconfig HZ_1000
1193c9218b16SRussell King	bool "1000 Hz"
1194c9218b16SRussell King
1195c9218b16SRussell Kingendchoice
1196c9218b16SRussell King
1197c9218b16SRussell Kingconfig HZ
1198c9218b16SRussell King	int
119947d84682SRussell King	default HZ_FIXED if HZ_FIXED != 0
1200c9218b16SRussell King	default 100 if HZ_100
1201c9218b16SRussell King	default 200 if HZ_200
1202c9218b16SRussell King	default 250 if HZ_250
1203c9218b16SRussell King	default 300 if HZ_300
1204c9218b16SRussell King	default 500 if HZ_500
1205c9218b16SRussell King	default 1000
1206c9218b16SRussell King
1207c9218b16SRussell Kingconfig SCHED_HRTICK
1208c9218b16SRussell King	def_bool HIGH_RES_TIMERS
1209f8065813SRussell King
121016c79651SCatalin Marinasconfig THUMB2_KERNEL
1211bc7dea00SUwe Kleine-König	bool "Compile the kernel in Thumb-2 mode" if !CPU_THUMBONLY
12124477ca45SUwe Kleine-König	depends on (CPU_V7 || CPU_V7M) && !CPU_V6 && !CPU_V6K
1213bc7dea00SUwe Kleine-König	default y if CPU_THUMBONLY
121489bace65SArnd Bergmann	select ARM_UNWIND
121516c79651SCatalin Marinas	help
121616c79651SCatalin Marinas	  By enabling this option, the kernel will be compiled in
121775fea300SNicolas Pitre	  Thumb-2 mode.
121816c79651SCatalin Marinas
121916c79651SCatalin Marinas	  If unsure, say N.
122016c79651SCatalin Marinas
122142f25bddSNicolas Pitreconfig ARM_PATCH_IDIV
122242f25bddSNicolas Pitre	bool "Runtime patch udiv/sdiv instructions into __aeabi_{u}idiv()"
12235408445bSArnd Bergmann	depends on CPU_32v7
122442f25bddSNicolas Pitre	default y
122542f25bddSNicolas Pitre	help
122642f25bddSNicolas Pitre	  The ARM compiler inserts calls to __aeabi_idiv() and
122742f25bddSNicolas Pitre	  __aeabi_uidiv() when it needs to perform division on signed
122842f25bddSNicolas Pitre	  and unsigned integers. Some v7 CPUs have support for the sdiv
122942f25bddSNicolas Pitre	  and udiv instructions that can be used to implement those
123042f25bddSNicolas Pitre	  functions.
123142f25bddSNicolas Pitre
123242f25bddSNicolas Pitre	  Enabling this option allows the kernel to modify itself to
123342f25bddSNicolas Pitre	  replace the first two instructions of these library functions
123442f25bddSNicolas Pitre	  with the sdiv or udiv plus "bx lr" instructions when the CPU
123542f25bddSNicolas Pitre	  it is running on supports them. Typically this will be faster
123642f25bddSNicolas Pitre	  and less power intensive than running the original library
123742f25bddSNicolas Pitre	  code to do integer division.
123842f25bddSNicolas Pitre
1239704bdda0SNicolas Pitreconfig AEABI
1240a05b9608SNick Desaulniers	bool "Use the ARM EABI to compile the kernel" if !CPU_V7 && \
1241a05b9608SNick Desaulniers		!CPU_V7M && !CPU_V6 && !CPU_V6K && !CC_IS_CLANG
1242a05b9608SNick Desaulniers	default CPU_V7 || CPU_V7M || CPU_V6 || CPU_V6K || CC_IS_CLANG
1243704bdda0SNicolas Pitre	help
1244704bdda0SNicolas Pitre	  This option allows for the kernel to be compiled using the latest
1245704bdda0SNicolas Pitre	  ARM ABI (aka EABI).  This is only useful if you are using a user
1246704bdda0SNicolas Pitre	  space environment that is also compiled with EABI.
1247704bdda0SNicolas Pitre
1248704bdda0SNicolas Pitre	  Since there are major incompatibilities between the legacy ABI and
1249704bdda0SNicolas Pitre	  EABI, especially with regard to structure member alignment, this
1250704bdda0SNicolas Pitre	  option also changes the kernel syscall calling convention to
1251704bdda0SNicolas Pitre	  disambiguate both ABIs and allow for backward compatibility support
1252704bdda0SNicolas Pitre	  (selected with CONFIG_OABI_COMPAT).
1253704bdda0SNicolas Pitre
1254704bdda0SNicolas Pitre	  To use this you need GCC version 4.0.0 or later.
1255704bdda0SNicolas Pitre
12566c90c872SNicolas Pitreconfig OABI_COMPAT
1257a73a3ff1SRussell King	bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1258d6f94fa0SKees Cook	depends on AEABI && !THUMB2_KERNEL
12596c90c872SNicolas Pitre	help
12606c90c872SNicolas Pitre	  This option preserves the old syscall interface along with the
12616c90c872SNicolas Pitre	  new (ARM EABI) one. It also provides a compatibility layer to
12626c90c872SNicolas Pitre	  intercept syscalls that have structure arguments which layout
12636c90c872SNicolas Pitre	  in memory differs between the legacy ABI and the new ARM EABI
12646c90c872SNicolas Pitre	  (only for non "thumb" binaries). This option adds a tiny
12656c90c872SNicolas Pitre	  overhead to all syscalls and produces a slightly larger kernel.
126691702175SKees Cook
126791702175SKees Cook	  The seccomp filter system will not be available when this is
126891702175SKees Cook	  selected, since there is no way yet to sensibly distinguish
126991702175SKees Cook	  between calling conventions during filtering.
127091702175SKees Cook
12716c90c872SNicolas Pitre	  If you know you'll be using only pure EABI user space then you
12726c90c872SNicolas Pitre	  can say N here. If this option is not selected and you attempt
12736c90c872SNicolas Pitre	  to execute a legacy ABI binary then the result will be
12746c90c872SNicolas Pitre	  UNPREDICTABLE (in fact it can be predicted that it won't work
1275b02f8467SKees Cook	  at all). If in doubt say N.
12766c90c872SNicolas Pitre
1277fb597f2aSGregory Fongconfig ARCH_SELECT_MEMORY_MODEL
12786fd09c9aSArnd Bergmann	def_bool y
127905944d74SRussell King
1280fb597f2aSGregory Fongconfig ARCH_FLATMEM_ENABLE
12816fd09c9aSArnd Bergmann	def_bool !(ARCH_RPC || ARCH_SA1100)
1282fb597f2aSGregory Fong
128305944d74SRussell Kingconfig ARCH_SPARSEMEM_ENABLE
12846fd09c9aSArnd Bergmann	def_bool !ARCH_FOOTBRIDGE
1285fb597f2aSGregory Fong	select SPARSEMEM_STATIC if SPARSEMEM
128607a2f737SRussell King
1287053a96caSNicolas Pitreconfig HIGHMEM
1288e8db89a2SRussell King	bool "High Memory Support"
1289e8db89a2SRussell King	depends on MMU
12902a15ba82SThomas Gleixner	select KMAP_LOCAL
1291825c43f5SArd Biesheuvel	select KMAP_LOCAL_NON_LINEAR_PTE_ARRAY
1292053a96caSNicolas Pitre	help
1293053a96caSNicolas Pitre	  The address space of ARM processors is only 4 Gigabytes large
1294053a96caSNicolas Pitre	  and it has to accommodate user address space, kernel address
1295053a96caSNicolas Pitre	  space as well as some memory mapped IO. That means that, if you
1296053a96caSNicolas Pitre	  have a large amount of physical memory and/or IO, not all of the
1297053a96caSNicolas Pitre	  memory can be "permanently mapped" by the kernel. The physical
1298053a96caSNicolas Pitre	  memory that is not permanently mapped is called "high memory".
1299053a96caSNicolas Pitre
1300053a96caSNicolas Pitre	  Depending on the selected kernel/user memory split, minimum
1301053a96caSNicolas Pitre	  vmalloc space and actual amount of RAM, you may not need this
1302053a96caSNicolas Pitre	  option which should result in a slightly faster kernel.
1303053a96caSNicolas Pitre
1304053a96caSNicolas Pitre	  If unsure, say n.
1305053a96caSNicolas Pitre
130665cec8e3SRussell Kingconfig HIGHPTE
13079a431bd5SRussell King	bool "Allocate 2nd-level pagetables from highmem" if EXPERT
130865cec8e3SRussell King	depends on HIGHMEM
13099a431bd5SRussell King	default y
1310b4d103d1SRussell King	help
1311b4d103d1SRussell King	  The VM uses one page of physical memory for each page table.
1312b4d103d1SRussell King	  For systems with a lot of processes, this can use a lot of
1313b4d103d1SRussell King	  precious low memory, eventually leading to low memory being
1314b4d103d1SRussell King	  consumed by page tables.  Setting this option will allow
1315b4d103d1SRussell King	  user-space 2nd level page tables to reside in high memory.
131665cec8e3SRussell King
1317a5e090acSRussell Kingconfig CPU_SW_DOMAIN_PAN
1318a5e090acSRussell King	bool "Enable use of CPU domains to implement privileged no-access"
1319a5e090acSRussell King	depends on MMU && !ARM_LPAE
13201b8873a0SJamie Iles	default y
13211b8873a0SJamie Iles	help
1322a5e090acSRussell King	  Increase kernel security by ensuring that normal kernel accesses
1323a5e090acSRussell King	  are unable to access userspace addresses.  This can help prevent
1324a5e090acSRussell King	  use-after-free bugs becoming an exploitable privilege escalation
1325a5e090acSRussell King	  by ensuring that magic values (such as LIST_POISON) will always
1326a5e090acSRussell King	  fault when dereferenced.
1327a5e090acSRussell King
1328a5e090acSRussell King	  CPUs with low-vector mappings use a best-efforts implementation.
1329a5e090acSRussell King	  Their lower 1MB needs to remain accessible for the vectors, but
1330a5e090acSRussell King	  the remainder of userspace will become appropriately inaccessible.
1331c80d79d7SYasunori Goto
1332c80d79d7SYasunori Gotoconfig HW_PERF_EVENTS
1333fa8ad788SMark Rutland	def_bool y
1334fa8ad788SMark Rutland	depends on ARM_PMU
13351b8873a0SJamie Iles
13367d485f64SArd Biesheuvelconfig ARM_MODULE_PLTS
13377d485f64SArd Biesheuvel	bool "Use PLTs to allow module memory to spill over into vmalloc area"
13387d485f64SArd Biesheuvel	depends on MODULES
13398fa7ea40SLecopzer Chen	select KASAN_VMALLOC if KASAN
1340e7229f7dSAnders Roxell	default y
13417d485f64SArd Biesheuvel	help
13427d485f64SArd Biesheuvel	  Allocate PLTs when loading modules so that jumps and calls whose
13437d485f64SArd Biesheuvel	  targets are too far away for their relative offsets to be encoded
13447d485f64SArd Biesheuvel	  in the instructions themselves can be bounced via veneers in the
13457d485f64SArd Biesheuvel	  module's PLT. This allows modules to be allocated in the generic
13467d485f64SArd Biesheuvel	  vmalloc area after the dedicated module memory area has been
13477d485f64SArd Biesheuvel	  exhausted. The modules will use slightly more memory, but after
13487d485f64SArd Biesheuvel	  rounding up to page size, the actual memory footprint is usually
13497d485f64SArd Biesheuvel	  the same.
13507d485f64SArd Biesheuvel
1351e7229f7dSAnders Roxell	  Disabling this is usually safe for small single-platform
1352e7229f7dSAnders Roxell	  configurations. If unsure, say y.
13537d485f64SArd Biesheuvel
13540192445cSZi Yanconfig ARCH_FORCE_MAX_ORDER
13558c907785SMike Rapoport (IBM)	int "Order of maximal physically contiguous allocations"
135623baf831SKirill A. Shutemov	default "11" if SOC_AM33XX
135723baf831SKirill A. Shutemov	default "8" if SA1111
135823baf831SKirill A. Shutemov	default "10"
1359c1b2d970SMagnus Damm	help
13608c907785SMike Rapoport (IBM)	  The kernel page allocator limits the size of maximal physically
13618c907785SMike Rapoport (IBM)	  contiguous allocations. The limit is called MAX_ORDER and it
13628c907785SMike Rapoport (IBM)	  defines the maximal power of two of number of pages that can be
13638c907785SMike Rapoport (IBM)	  allocated as a single contiguous block. This option allows
13648c907785SMike Rapoport (IBM)	  overriding the default setting when ability to allocate very
13658c907785SMike Rapoport (IBM)	  large blocks of physically contiguous memory is required.
1366c1b2d970SMagnus Damm
13678c907785SMike Rapoport (IBM)	  Don't change if unsure.
1368c1b2d970SMagnus Damm
13691da177e4SLinus Torvaldsconfig ALIGNMENT_TRAP
13703e3f354bSArnd Bergmann	def_bool CPU_CP15_MMU
1371e119bfffSRussell King	select HAVE_PROC_CPU if PROC_FS
13721da177e4SLinus Torvalds	help
13731da177e4SLinus Torvalds	  ARM processors cannot fetch/store information which is not
13741da177e4SLinus Torvalds	  naturally aligned on the bus, i.e., a 4 byte fetch must start at an
13751da177e4SLinus Torvalds	  address divisible by 4. On 32-bit ARM processors, these non-aligned
13761da177e4SLinus Torvalds	  fetch/store instructions will be emulated in software if you say
13771da177e4SLinus Torvalds	  here, which has a severe performance impact. This is necessary for
13781da177e4SLinus Torvalds	  correct operation of some network protocols. With an IP-only
13791da177e4SLinus Torvalds	  configuration it is safe to say N, otherwise say Y.
13801da177e4SLinus Torvalds
138139ec58f3SLennert Buytenhekconfig UACCESS_WITH_MEMCPY
138238ef2ad5SLinus Walleij	bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user()"
138338ef2ad5SLinus Walleij	depends on MMU
138439ec58f3SLennert Buytenhek	default y if CPU_FEROCEON
138539ec58f3SLennert Buytenhek	help
138639ec58f3SLennert Buytenhek	  Implement faster copy_to_user and clear_user methods for CPU
138739ec58f3SLennert Buytenhek	  cores where a 8-word STM instruction give significantly higher
138839ec58f3SLennert Buytenhek	  memory write throughput than a sequence of individual 32bit stores.
138939ec58f3SLennert Buytenhek
139039ec58f3SLennert Buytenhek	  A possible side effect is a slight increase in scheduling latency
139139ec58f3SLennert Buytenhek	  between threads sharing the same address space if they invoke
139239ec58f3SLennert Buytenhek	  such copy operations with large buffers.
139339ec58f3SLennert Buytenhek
139439ec58f3SLennert Buytenhek	  However, if the CPU data cache is using a write-allocate mode,
139539ec58f3SLennert Buytenhek	  this option is unlikely to provide any performance gain.
139639ec58f3SLennert Buytenhek
139702c2433bSStefano Stabelliniconfig PARAVIRT
139802c2433bSStefano Stabellini	bool "Enable paravirtualization code"
139902c2433bSStefano Stabellini	help
140002c2433bSStefano Stabellini	  This changes the kernel so it can modify itself when it is run
140102c2433bSStefano Stabellini	  under a hypervisor, potentially improving performance significantly
140202c2433bSStefano Stabellini	  over full virtualization.
140302c2433bSStefano Stabellini
140402c2433bSStefano Stabelliniconfig PARAVIRT_TIME_ACCOUNTING
140502c2433bSStefano Stabellini	bool "Paravirtual steal time accounting"
140602c2433bSStefano Stabellini	select PARAVIRT
140702c2433bSStefano Stabellini	help
140802c2433bSStefano Stabellini	  Select this option to enable fine granularity task steal time
140902c2433bSStefano Stabellini	  accounting. Time spent executing other tasks in parallel with
141002c2433bSStefano Stabellini	  the current vCPU is discounted from the vCPU power. To account for
141102c2433bSStefano Stabellini	  that, there can be a small performance impact.
141202c2433bSStefano Stabellini
141302c2433bSStefano Stabellini	  If in doubt, say N here.
141402c2433bSStefano Stabellini
1415eff8d644SStefano Stabelliniconfig XEN_DOM0
1416eff8d644SStefano Stabellini	def_bool y
1417eff8d644SStefano Stabellini	depends on XEN
1418eff8d644SStefano Stabellini
1419eff8d644SStefano Stabelliniconfig XEN
1420c2ba1f7dSJulien Grall	bool "Xen guest support on ARM"
142185323a99SIan Campbell	depends on ARM && AEABI && OF
1422f880b67dSArnd Bergmann	depends on CPU_V7 && !CPU_V6
142385323a99SIan Campbell	depends on !GENERIC_ATOMIC64
14247693deccSUwe Kleine-König	depends on MMU
142551aaf81fSRussell King	select ARCH_DMA_ADDR_T_64BIT
142617b7ab80SStefano Stabellini	select ARM_PSCI
1427f21254cdSChristoph Hellwig	select SWIOTLB
142883862ccfSStefano Stabellini	select SWIOTLB_XEN
142902c2433bSStefano Stabellini	select PARAVIRT
1430eff8d644SStefano Stabellini	help
1431eff8d644SStefano Stabellini	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
1432eff8d644SStefano Stabellini
1433f05eb1d2SArd Biesheuvelconfig CC_HAVE_STACKPROTECTOR_TLS
1434f05eb1d2SArd Biesheuvel	def_bool $(cc-option,-mtp=cp15 -mstack-protector-guard=tls -mstack-protector-guard-offset=0)
1435f05eb1d2SArd Biesheuvel
1436189af465SArd Biesheuvelconfig STACKPROTECTOR_PER_TASK
1437189af465SArd Biesheuvel	bool "Use a unique stack canary value for each task"
14389c46929eSArd Biesheuvel	depends on STACKPROTECTOR && CURRENT_POINTER_IN_TPIDRURO && !XIP_DEFLATED_DATA
1439f05eb1d2SArd Biesheuvel	depends on GCC_PLUGINS || CC_HAVE_STACKPROTECTOR_TLS
1440f05eb1d2SArd Biesheuvel	select GCC_PLUGIN_ARM_SSP_PER_TASK if !CC_HAVE_STACKPROTECTOR_TLS
1441189af465SArd Biesheuvel	default y
1442189af465SArd Biesheuvel	help
1443189af465SArd Biesheuvel	  Due to the fact that GCC uses an ordinary symbol reference from
1444189af465SArd Biesheuvel	  which to load the value of the stack canary, this value can only
1445189af465SArd Biesheuvel	  change at reboot time on SMP systems, and all tasks running in the
1446189af465SArd Biesheuvel	  kernel's address space are forced to use the same canary value for
1447189af465SArd Biesheuvel	  the entire duration that the system is up.
1448189af465SArd Biesheuvel
1449189af465SArd Biesheuvel	  Enable this option to switch to a different method that uses a
1450189af465SArd Biesheuvel	  different canary value for each task.
1451189af465SArd Biesheuvel
14521da177e4SLinus Torvaldsendmenu
14531da177e4SLinus Torvalds
14541da177e4SLinus Torvaldsmenu "Boot options"
14551da177e4SLinus Torvalds
14569eb8f674SGrant Likelyconfig USE_OF
14579eb8f674SGrant Likely	bool "Flattened Device Tree support"
1458b1b3f49cSRussell King	select IRQ_DOMAIN
14599eb8f674SGrant Likely	select OF
14609eb8f674SGrant Likely	help
14619eb8f674SGrant Likely	  Include support for flattened device tree machine descriptions.
14629eb8f674SGrant Likely
1463bd51e2f5SNicolas Pitreconfig ATAGS
146496a4ce30SArnd Bergmann	bool "Support for the traditional ATAGS boot data passing"
1465bd51e2f5SNicolas Pitre	default y
1466bd51e2f5SNicolas Pitre	help
1467bd51e2f5SNicolas Pitre	  This is the traditional way of passing data to the kernel at boot
1468bd51e2f5SNicolas Pitre	  time. If you are solely relying on the flattened device tree (or
1469bd51e2f5SNicolas Pitre	  the ARM_ATAG_DTB_COMPAT option) then you may unselect this option
1470acb926d6SArnd Bergmann	  to remove ATAGS support from your kernel binary.
1471acb926d6SArnd Bergmann
1472bd51e2f5SNicolas Pitreconfig DEPRECATED_PARAM_STRUCT
1473bd51e2f5SNicolas Pitre	bool "Provide old way to pass kernel parameters"
1474bd51e2f5SNicolas Pitre	depends on ATAGS
1475bd51e2f5SNicolas Pitre	help
1476bd51e2f5SNicolas Pitre	  This was deprecated in 2001 and announced to live on for 5 years.
1477bd51e2f5SNicolas Pitre	  Some old boot loaders still use this way.
1478bd51e2f5SNicolas Pitre
14791da177e4SLinus Torvalds# Compressed boot loader in ROM.  Yes, we really want to ask about
14801da177e4SLinus Torvalds# TEXT and BSS so we preserve their values in the config files.
14811da177e4SLinus Torvaldsconfig ZBOOT_ROM_TEXT
14821da177e4SLinus Torvalds	hex "Compressed ROM boot loader base address"
148339c3e304SChris Packham	default 0x0
14841da177e4SLinus Torvalds	help
14851da177e4SLinus Torvalds	  The physical address at which the ROM-able zImage is to be
14861da177e4SLinus Torvalds	  placed in the target.  Platforms which normally make use of
14871da177e4SLinus Torvalds	  ROM-able zImage formats normally set this to a suitable
14881da177e4SLinus Torvalds	  value in their defconfig file.
14891da177e4SLinus Torvalds
14901da177e4SLinus Torvalds	  If ZBOOT_ROM is not enabled, this has no effect.
14911da177e4SLinus Torvalds
14921da177e4SLinus Torvaldsconfig ZBOOT_ROM_BSS
14931da177e4SLinus Torvalds	hex "Compressed ROM boot loader BSS address"
149439c3e304SChris Packham	default 0x0
14951da177e4SLinus Torvalds	help
1496f8c440b2SDan Fandrich	  The base address of an area of read/write memory in the target
1497f8c440b2SDan Fandrich	  for the ROM-able zImage which must be available while the
1498f8c440b2SDan Fandrich	  decompressor is running. It must be large enough to hold the
1499f8c440b2SDan Fandrich	  entire decompressed kernel plus an additional 128 KiB.
1500f8c440b2SDan Fandrich	  Platforms which normally make use of ROM-able zImage formats
1501f8c440b2SDan Fandrich	  normally set this to a suitable value in their defconfig file.
15021da177e4SLinus Torvalds
15031da177e4SLinus Torvalds	  If ZBOOT_ROM is not enabled, this has no effect.
15041da177e4SLinus Torvalds
15051da177e4SLinus Torvaldsconfig ZBOOT_ROM
15061da177e4SLinus Torvalds	bool "Compressed boot loader in ROM/flash"
15071da177e4SLinus Torvalds	depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
150810968131SRussell King	depends on !ARM_APPENDED_DTB && !XIP_KERNEL && !AUTO_ZRELADDR
15091da177e4SLinus Torvalds	help
15101da177e4SLinus Torvalds	  Say Y here if you intend to execute your compressed kernel image
15111da177e4SLinus Torvalds	  (zImage) directly from ROM or flash.  If unsure, say N.
15121da177e4SLinus Torvalds
1513e2a6a3aaSJohn Bonesioconfig ARM_APPENDED_DTB
1514e2a6a3aaSJohn Bonesio	bool "Use appended device tree blob to zImage (EXPERIMENTAL)"
151510968131SRussell King	depends on OF
1516e2a6a3aaSJohn Bonesio	help
1517e2a6a3aaSJohn Bonesio	  With this option, the boot code will look for a device tree binary
1518e2a6a3aaSJohn Bonesio	  (DTB) appended to zImage
1519e2a6a3aaSJohn Bonesio	  (e.g. cat zImage <filename>.dtb > zImage_w_dtb).
1520e2a6a3aaSJohn Bonesio
1521e2a6a3aaSJohn Bonesio	  This is meant as a backward compatibility convenience for those
1522e2a6a3aaSJohn Bonesio	  systems with a bootloader that can't be upgraded to accommodate
1523e2a6a3aaSJohn Bonesio	  the documented boot protocol using a device tree.
1524e2a6a3aaSJohn Bonesio
1525e2a6a3aaSJohn Bonesio	  Beware that there is very little in terms of protection against
1526e2a6a3aaSJohn Bonesio	  this option being confused by leftover garbage in memory that might
1527e2a6a3aaSJohn Bonesio	  look like a DTB header after a reboot if no actual DTB is appended
1528e2a6a3aaSJohn Bonesio	  to zImage.  Do not leave this option active in a production kernel
1529e2a6a3aaSJohn Bonesio	  if you don't intend to always append a DTB.  Proper passing of the
1530e2a6a3aaSJohn Bonesio	  location into r2 of a bootloader provided DTB is always preferable
1531e2a6a3aaSJohn Bonesio	  to this option.
1532e2a6a3aaSJohn Bonesio
1533b90b9a38SNicolas Pitreconfig ARM_ATAG_DTB_COMPAT
1534b90b9a38SNicolas Pitre	bool "Supplement the appended DTB with traditional ATAG information"
1535b90b9a38SNicolas Pitre	depends on ARM_APPENDED_DTB
1536b90b9a38SNicolas Pitre	help
1537b90b9a38SNicolas Pitre	  Some old bootloaders can't be updated to a DTB capable one, yet
1538b90b9a38SNicolas Pitre	  they provide ATAGs with memory configuration, the ramdisk address,
1539b90b9a38SNicolas Pitre	  the kernel cmdline string, etc.  Such information is dynamically
1540b90b9a38SNicolas Pitre	  provided by the bootloader and can't always be stored in a static
1541b90b9a38SNicolas Pitre	  DTB.  To allow a device tree enabled kernel to be used with such
1542b90b9a38SNicolas Pitre	  bootloaders, this option allows zImage to extract the information
1543b90b9a38SNicolas Pitre	  from the ATAG list and store it at run time into the appended DTB.
1544b90b9a38SNicolas Pitre
1545d0f34a11SGenoud Richardchoice
1546d0f34a11SGenoud Richard	prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT
1547d0f34a11SGenoud Richard	default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1548d0f34a11SGenoud Richard
1549d0f34a11SGenoud Richardconfig ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1550d0f34a11SGenoud Richard	bool "Use bootloader kernel arguments if available"
1551d0f34a11SGenoud Richard	help
1552d0f34a11SGenoud Richard	  Uses the command-line options passed by the boot loader instead of
1553d0f34a11SGenoud Richard	  the device tree bootargs property. If the boot loader doesn't provide
1554d0f34a11SGenoud Richard	  any, the device tree bootargs property will be used.
1555d0f34a11SGenoud Richard
1556d0f34a11SGenoud Richardconfig ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND
1557d0f34a11SGenoud Richard	bool "Extend with bootloader kernel arguments"
1558d0f34a11SGenoud Richard	help
1559d0f34a11SGenoud Richard	  The command-line arguments provided by the boot loader will be
1560d0f34a11SGenoud Richard	  appended to the the device tree bootargs property.
1561d0f34a11SGenoud Richard
1562d0f34a11SGenoud Richardendchoice
1563d0f34a11SGenoud Richard
15641da177e4SLinus Torvaldsconfig CMDLINE
15651da177e4SLinus Torvalds	string "Default kernel command string"
15661da177e4SLinus Torvalds	default ""
15671da177e4SLinus Torvalds	help
15683e3f354bSArnd Bergmann	  On some architectures (e.g. CATS), there is currently no way
15691da177e4SLinus Torvalds	  for the boot loader to pass arguments to the kernel. For these
15701da177e4SLinus Torvalds	  architectures, you should supply some command-line options at build
15711da177e4SLinus Torvalds	  time by entering them here. As a minimum, you should specify the
15721da177e4SLinus Torvalds	  memory size and the root device (e.g., mem=64M root=/dev/nfs).
15731da177e4SLinus Torvalds
15744394c124SVictor Boiviechoice
15754394c124SVictor Boivie	prompt "Kernel command line type" if CMDLINE != ""
15764394c124SVictor Boivie	default CMDLINE_FROM_BOOTLOADER
15774394c124SVictor Boivie
15784394c124SVictor Boivieconfig CMDLINE_FROM_BOOTLOADER
15794394c124SVictor Boivie	bool "Use bootloader kernel arguments if available"
15804394c124SVictor Boivie	help
15814394c124SVictor Boivie	  Uses the command-line options passed by the boot loader. If
15824394c124SVictor Boivie	  the boot loader doesn't provide any, the default kernel command
15834394c124SVictor Boivie	  string provided in CMDLINE will be used.
15844394c124SVictor Boivie
15854394c124SVictor Boivieconfig CMDLINE_EXTEND
15864394c124SVictor Boivie	bool "Extend bootloader kernel arguments"
15874394c124SVictor Boivie	help
15884394c124SVictor Boivie	  The command-line arguments provided by the boot loader will be
15894394c124SVictor Boivie	  appended to the default kernel command string.
15904394c124SVictor Boivie
159192d2040dSAlexander Hollerconfig CMDLINE_FORCE
159292d2040dSAlexander Holler	bool "Always use the default kernel command string"
159392d2040dSAlexander Holler	help
159492d2040dSAlexander Holler	  Always use the default kernel command string, even if the boot
159592d2040dSAlexander Holler	  loader passes other arguments to the kernel.
159692d2040dSAlexander Holler	  This is useful if you cannot or don't want to change the
159792d2040dSAlexander Holler	  command-line options your boot loader passes to the kernel.
15984394c124SVictor Boivieendchoice
159992d2040dSAlexander Holler
16001da177e4SLinus Torvaldsconfig XIP_KERNEL
16011da177e4SLinus Torvalds	bool "Kernel Execute-In-Place from ROM"
160210968131SRussell King	depends on !ARM_LPAE && !ARCH_MULTIPLATFORM
16035408445bSArnd Bergmann	depends on !ARM_PATCH_IDIV && !ARM_PATCH_PHYS_VIRT && !SMP_ON_UP
16041da177e4SLinus Torvalds	help
16051da177e4SLinus Torvalds	  Execute-In-Place allows the kernel to run from non-volatile storage
16061da177e4SLinus Torvalds	  directly addressable by the CPU, such as NOR flash. This saves RAM
16071da177e4SLinus Torvalds	  space since the text section of the kernel is not loaded from flash
16081da177e4SLinus Torvalds	  to RAM.  Read-write sections, such as the data section and stack,
16091da177e4SLinus Torvalds	  are still copied to RAM.  The XIP kernel is not compressed since
16101da177e4SLinus Torvalds	  it has to run directly from flash, so it will take more space to
16111da177e4SLinus Torvalds	  store it.  The flash address used to link the kernel object files,
16121da177e4SLinus Torvalds	  and for storing it, is configuration dependent. Therefore, if you
16131da177e4SLinus Torvalds	  say Y here, you must know the proper physical address where to
16141da177e4SLinus Torvalds	  store the kernel image depending on your own flash memory usage.
16151da177e4SLinus Torvalds
16161da177e4SLinus Torvalds	  Also note that the make target becomes "make xipImage" rather than
16171da177e4SLinus Torvalds	  "make zImage" or "make Image".  The final kernel binary to put in
16181da177e4SLinus Torvalds	  ROM memory will be arch/arm/boot/xipImage.
16191da177e4SLinus Torvalds
16201da177e4SLinus Torvalds	  If unsure, say N.
16211da177e4SLinus Torvalds
16221da177e4SLinus Torvaldsconfig XIP_PHYS_ADDR
16231da177e4SLinus Torvalds	hex "XIP Kernel Physical Location"
16241da177e4SLinus Torvalds	depends on XIP_KERNEL
16251da177e4SLinus Torvalds	default "0x00080000"
16261da177e4SLinus Torvalds	help
16271da177e4SLinus Torvalds	  This is the physical address in your flash memory the kernel will
16281da177e4SLinus Torvalds	  be linked for and stored to.  This address is dependent on your
16291da177e4SLinus Torvalds	  own flash usage.
16301da177e4SLinus Torvalds
1631ca8b5d97SNicolas Pitreconfig XIP_DEFLATED_DATA
1632ca8b5d97SNicolas Pitre	bool "Store kernel .data section compressed in ROM"
1633ca8b5d97SNicolas Pitre	depends on XIP_KERNEL
1634ca8b5d97SNicolas Pitre	select ZLIB_INFLATE
1635ca8b5d97SNicolas Pitre	help
1636ca8b5d97SNicolas Pitre	  Before the kernel is actually executed, its .data section has to be
1637ca8b5d97SNicolas Pitre	  copied to RAM from ROM. This option allows for storing that data
1638ca8b5d97SNicolas Pitre	  in compressed form and decompressed to RAM rather than merely being
1639ca8b5d97SNicolas Pitre	  copied, saving some precious ROM space. A possible drawback is a
1640ca8b5d97SNicolas Pitre	  slightly longer boot delay.
1641ca8b5d97SNicolas Pitre
1642c587e4a6SRichard Purdieconfig KEXEC
1643c587e4a6SRichard Purdie	bool "Kexec system call (EXPERIMENTAL)"
164419ab428fSStephen Warren	depends on (!SMP || PM_SLEEP_SMP)
164576950f71SVincenzo Frascino	depends on MMU
16462965faa5SDave Young	select KEXEC_CORE
1647c587e4a6SRichard Purdie	help
1648c587e4a6SRichard Purdie	  kexec is a system call that implements the ability to shutdown your
1649c587e4a6SRichard Purdie	  current kernel, and to start another kernel.  It is like a reboot
165001dd2fbfSMatt LaPlante	  but it is independent of the system firmware.   And like a reboot
1651c587e4a6SRichard Purdie	  you can start any kernel with it, not just Linux.
1652c587e4a6SRichard Purdie
1653c587e4a6SRichard Purdie	  It is an ongoing process to be certain the hardware in a machine
1654c587e4a6SRichard Purdie	  is properly shutdown, so do not be surprised if this code does not
1655bf220695SGeert Uytterhoeven	  initially work for you.
1656c587e4a6SRichard Purdie
16574cd9d6f7SRichard Purdieconfig ATAGS_PROC
16584cd9d6f7SRichard Purdie	bool "Export atags in procfs"
1659bd51e2f5SNicolas Pitre	depends on ATAGS && KEXEC
1660b98d7291SUli Luckas	default y
16614cd9d6f7SRichard Purdie	help
16624cd9d6f7SRichard Purdie	  Should the atags used to boot the kernel be exported in an "atags"
16634cd9d6f7SRichard Purdie	  file in procfs. Useful with kexec.
16644cd9d6f7SRichard Purdie
1665cb5d39b3SMika Westerbergconfig CRASH_DUMP
1666cb5d39b3SMika Westerberg	bool "Build kdump crash kernel (EXPERIMENTAL)"
1667cb5d39b3SMika Westerberg	help
1668cb5d39b3SMika Westerberg	  Generate crash dump after being started by kexec. This should
1669cb5d39b3SMika Westerberg	  be normally only set in special crash dump kernels which are
1670cb5d39b3SMika Westerberg	  loaded in the main kernel with kexec-tools into a specially
1671cb5d39b3SMika Westerberg	  reserved region and then later executed after a crash by
1672cb5d39b3SMika Westerberg	  kdump/kexec. The crash dump kernel must be compiled to a
1673cb5d39b3SMika Westerberg	  memory address not used by the main kernel
1674cb5d39b3SMika Westerberg
1675330d4810SMauro Carvalho Chehab	  For more details see Documentation/admin-guide/kdump/kdump.rst
1676cb5d39b3SMika Westerberg
1677e69edc79SEric Miaoconfig AUTO_ZRELADDR
16786fd09c9aSArnd Bergmann	bool "Auto calculation of the decompressed kernel image address" if !ARCH_MULTIPLATFORM
16796fd09c9aSArnd Bergmann	default !(ARCH_FOOTBRIDGE || ARCH_RPC || ARCH_SA1100)
1680e69edc79SEric Miao	help
1681e69edc79SEric Miao	  ZRELADDR is the physical address where the decompressed kernel
1682e69edc79SEric Miao	  image will be placed. If AUTO_ZRELADDR is selected, the address
16830673cb38SGeert Uytterhoeven	  will be determined at run-time, either by masking the current IP
16840673cb38SGeert Uytterhoeven	  with 0xf8000000, or, if invalid, from the DTB passed in r2.
16850673cb38SGeert Uytterhoeven	  This assumes the zImage being placed in the first 128MB from
16860673cb38SGeert Uytterhoeven	  start of memory.
1687e69edc79SEric Miao
168881a0bc39SRoy Franzconfig EFI_STUB
168981a0bc39SRoy Franz	bool
169081a0bc39SRoy Franz
169181a0bc39SRoy Franzconfig EFI
169281a0bc39SRoy Franz	bool "UEFI runtime support"
169381a0bc39SRoy Franz	depends on OF && !CPU_BIG_ENDIAN && MMU && AUTO_ZRELADDR && !XIP_KERNEL
169481a0bc39SRoy Franz	select UCS2_STRING
169581a0bc39SRoy Franz	select EFI_PARAMS_FROM_FDT
169681a0bc39SRoy Franz	select EFI_STUB
16972e0eb483SAtish Patra	select EFI_GENERIC_STUB
169881a0bc39SRoy Franz	select EFI_RUNTIME_WRAPPERS
1699a7f7f624SMasahiro Yamada	help
170081a0bc39SRoy Franz	  This option provides support for runtime services provided
170181a0bc39SRoy Franz	  by UEFI firmware (such as non-volatile variables, realtime
170281a0bc39SRoy Franz	  clock, and platform reset). A UEFI stub is also provided to
170381a0bc39SRoy Franz	  allow the kernel to be booted as an EFI application. This
170481a0bc39SRoy Franz	  is only useful for kernels that may run on systems that have
170581a0bc39SRoy Franz	  UEFI firmware.
170681a0bc39SRoy Franz
1707bb817befSArd Biesheuvelconfig DMI
1708bb817befSArd Biesheuvel	bool "Enable support for SMBIOS (DMI) tables"
1709bb817befSArd Biesheuvel	depends on EFI
1710bb817befSArd Biesheuvel	default y
1711bb817befSArd Biesheuvel	help
1712bb817befSArd Biesheuvel	  This enables SMBIOS/DMI feature for systems.
1713bb817befSArd Biesheuvel
1714bb817befSArd Biesheuvel	  This option is only useful on systems that have UEFI firmware.
1715bb817befSArd Biesheuvel	  However, even with this option, the resultant kernel should
1716bb817befSArd Biesheuvel	  continue to boot on existing non-UEFI platforms.
1717bb817befSArd Biesheuvel
1718bb817befSArd Biesheuvel	  NOTE: This does *NOT* enable or encourage the use of DMI quirks,
1719bb817befSArd Biesheuvel	  i.e., the the practice of identifying the platform via DMI to
1720bb817befSArd Biesheuvel	  decide whether certain workarounds for buggy hardware and/or
1721bb817befSArd Biesheuvel	  firmware need to be enabled. This would require the DMI subsystem
1722bb817befSArd Biesheuvel	  to be enabled much earlier than we do on ARM, which is non-trivial.
1723bb817befSArd Biesheuvel
17241da177e4SLinus Torvaldsendmenu
17251da177e4SLinus Torvalds
1726ac9d7efcSRussell Kingmenu "CPU Power Management"
17271da177e4SLinus Torvalds
17281da177e4SLinus Torvaldssource "drivers/cpufreq/Kconfig"
17291da177e4SLinus Torvalds
1730ac9d7efcSRussell Kingsource "drivers/cpuidle/Kconfig"
1731ac9d7efcSRussell King
1732ac9d7efcSRussell Kingendmenu
1733ac9d7efcSRussell King
17341da177e4SLinus Torvaldsmenu "Floating point emulation"
17351da177e4SLinus Torvalds
17361da177e4SLinus Torvaldscomment "At least one emulation must be selected"
17371da177e4SLinus Torvalds
17381da177e4SLinus Torvaldsconfig FPE_NWFPE
17391da177e4SLinus Torvalds	bool "NWFPE math emulation"
1740593c252aSDave Martin	depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL
1741a7f7f624SMasahiro Yamada	help
17421da177e4SLinus Torvalds	  Say Y to include the NWFPE floating point emulator in the kernel.
17431da177e4SLinus Torvalds	  This is necessary to run most binaries. Linux does not currently
17441da177e4SLinus Torvalds	  support floating point hardware so you need to say Y here even if
17451da177e4SLinus Torvalds	  your machine has an FPA or floating point co-processor podule.
17461da177e4SLinus Torvalds
17471da177e4SLinus Torvalds	  You may say N here if you are going to load the Acorn FPEmulator
17481da177e4SLinus Torvalds	  early in the bootup.
17491da177e4SLinus Torvalds
17501da177e4SLinus Torvaldsconfig FPE_NWFPE_XP
17511da177e4SLinus Torvalds	bool "Support extended precision"
1752bedf142bSLennert Buytenhek	depends on FPE_NWFPE
17531da177e4SLinus Torvalds	help
17541da177e4SLinus Torvalds	  Say Y to include 80-bit support in the kernel floating-point
17551da177e4SLinus Torvalds	  emulator.  Otherwise, only 32 and 64-bit support is compiled in.
17561da177e4SLinus Torvalds	  Note that gcc does not generate 80-bit operations by default,
17571da177e4SLinus Torvalds	  so in most cases this option only enlarges the size of the
17581da177e4SLinus Torvalds	  floating point emulator without any good reason.
17591da177e4SLinus Torvalds
17601da177e4SLinus Torvalds	  You almost surely want to say N here.
17611da177e4SLinus Torvalds
17621da177e4SLinus Torvaldsconfig FPE_FASTFPE
17631da177e4SLinus Torvalds	bool "FastFPE math emulation (EXPERIMENTAL)"
1764d6f94fa0SKees Cook	depends on (!AEABI || OABI_COMPAT) && !CPU_32v3
1765a7f7f624SMasahiro Yamada	help
17661da177e4SLinus Torvalds	  Say Y here to include the FAST floating point emulator in the kernel.
17671da177e4SLinus Torvalds	  This is an experimental much faster emulator which now also has full
17681da177e4SLinus Torvalds	  precision for the mantissa.  It does not support any exceptions.
17691da177e4SLinus Torvalds	  It is very simple, and approximately 3-6 times faster than NWFPE.
17701da177e4SLinus Torvalds
17711da177e4SLinus Torvalds	  It should be sufficient for most programs.  It may be not suitable
17721da177e4SLinus Torvalds	  for scientific calculations, but you have to check this for yourself.
17731da177e4SLinus Torvalds	  If you do not feel you need a faster FP emulation you should better
17741da177e4SLinus Torvalds	  choose NWFPE.
17751da177e4SLinus Torvalds
17761da177e4SLinus Torvaldsconfig VFP
17771da177e4SLinus Torvalds	bool "VFP-format floating point maths"
1778e399b1a4SRussell King	depends on CPU_V6 || CPU_V6K || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
17791da177e4SLinus Torvalds	help
17801da177e4SLinus Torvalds	  Say Y to include VFP support code in the kernel. This is needed
17811da177e4SLinus Torvalds	  if your hardware includes a VFP unit.
17821da177e4SLinus Torvalds
1783*e318b36eSJonathan Corbet	  Please see <file:Documentation/arch/arm/vfp/release-notes.rst> for
17841da177e4SLinus Torvalds	  release notes and additional status information.
17851da177e4SLinus Torvalds
17861da177e4SLinus Torvalds	  Say N if your target does not have VFP hardware.
17871da177e4SLinus Torvalds
178825ebee02SCatalin Marinasconfig VFPv3
178925ebee02SCatalin Marinas	bool
179025ebee02SCatalin Marinas	depends on VFP
179125ebee02SCatalin Marinas	default y if CPU_V7
179225ebee02SCatalin Marinas
1793b5872db4SCatalin Marinasconfig NEON
1794b5872db4SCatalin Marinas	bool "Advanced SIMD (NEON) Extension support"
1795b5872db4SCatalin Marinas	depends on VFPv3 && CPU_V7
1796b5872db4SCatalin Marinas	help
1797b5872db4SCatalin Marinas	  Say Y to include support code for NEON, the ARMv7 Advanced SIMD
1798b5872db4SCatalin Marinas	  Extension.
1799b5872db4SCatalin Marinas
180073c132c1SArd Biesheuvelconfig KERNEL_MODE_NEON
180173c132c1SArd Biesheuvel	bool "Support for NEON in kernel mode"
1802c4a30c3bSRussell King	depends on NEON && AEABI
180373c132c1SArd Biesheuvel	help
180473c132c1SArd Biesheuvel	  Say Y to include support for NEON in kernel mode.
180573c132c1SArd Biesheuvel
18061da177e4SLinus Torvaldsendmenu
18071da177e4SLinus Torvalds
18081da177e4SLinus Torvaldsmenu "Power management options"
18091da177e4SLinus Torvalds
1810eceab4acSRussell Kingsource "kernel/power/Kconfig"
18111da177e4SLinus Torvalds
1812f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE
181319a0519dSEzequiel Garcia	depends on CPU_ARM920T || CPU_ARM926T || CPU_FEROCEON || CPU_SA1100 || \
1814f0d75153SUwe Kleine-König		CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7M || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK
1815f4cb5700SJohannes Berg	def_bool y
1816f4cb5700SJohannes Berg
181715e0d9e3SArnd Bergmannconfig ARM_CPU_SUSPEND
18188b6f2499SLorenzo Pieralisi	def_bool PM_SLEEP || BL_SWITCHER || ARM_PSCI_FW
18191b9bdf5cSLorenzo Pieralisi	depends on ARCH_SUSPEND_POSSIBLE
182015e0d9e3SArnd Bergmann
1821603fb42aSSebastian Capellaconfig ARCH_HIBERNATION_POSSIBLE
1822603fb42aSSebastian Capella	bool
1823603fb42aSSebastian Capella	depends on MMU
1824603fb42aSSebastian Capella	default y if ARCH_SUSPEND_POSSIBLE
1825603fb42aSSebastian Capella
18261da177e4SLinus Torvaldsendmenu
18271da177e4SLinus Torvalds
18282cbd1cc3SStefan Agnersource "arch/arm/Kconfig.assembler"
1829