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1# SPDX-License-Identifier: GPL-2.0
2config ARM
3 bool
4 default y
5 select ARCH_32BIT_OFF_T
6 select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE if HAVE_KRETPROBES && FRAME_POINTER && !ARM_UNWIND
7 select ARCH_HAS_BINFMT_FLAT
8 select ARCH_HAS_CPU_CACHE_ALIASING
9 select ARCH_HAS_CPU_FINALIZE_INIT if MMU
10 select ARCH_HAS_CURRENT_STACK_POINTER
11 select ARCH_HAS_DEBUG_VIRTUAL if MMU
12 select ARCH_HAS_DMA_ALLOC if MMU
13 select ARCH_HAS_DMA_OPS
14 select ARCH_HAS_DMA_WRITE_COMBINE if !ARM_DMA_MEM_BUFFERABLE
15 select ARCH_HAS_ELF_RANDOMIZE
16 select ARCH_HAS_FORTIFY_SOURCE
17 select ARCH_HAS_KEEPINITRD
18 select ARCH_HAS_KCOV
19 select ARCH_HAS_MEMBARRIER_SYNC_CORE
20 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
21 select ARCH_HAS_PTE_SPECIAL if ARM_LPAE
22 select ARCH_HAS_SETUP_DMA_OPS
23 select ARCH_HAS_SET_MEMORY
24 select ARCH_STACKWALK
25 select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
26 select ARCH_HAS_STRICT_MODULE_RWX if MMU
27 select ARCH_HAS_SYNC_DMA_FOR_DEVICE
28 select ARCH_HAS_SYNC_DMA_FOR_CPU
29 select ARCH_HAS_TEARDOWN_DMA_OPS if MMU
30 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
31 select ARCH_HAVE_NMI_SAFE_CMPXCHG if CPU_V7 || CPU_V7M || CPU_V6K
32 select ARCH_HAS_GCOV_PROFILE_ALL
33 select ARCH_KEEP_MEMBLOCK
34 select ARCH_HAS_UBSAN
35 select ARCH_MIGHT_HAVE_PC_PARPORT
36 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
37 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT if CPU_V7
38 select ARCH_NEED_CMPXCHG_1_EMU if CPU_V6
39 select ARCH_SUPPORTS_ATOMIC_RMW
40 select ARCH_SUPPORTS_CFI_CLANG
41 select ARCH_SUPPORTS_HUGETLBFS if ARM_LPAE
42 select ARCH_SUPPORTS_PER_VMA_LOCK
43 select ARCH_USE_BUILTIN_BSWAP
44 select ARCH_USE_CMPXCHG_LOCKREF
45 select ARCH_USE_MEMTEST
46 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
47 select ARCH_WANT_GENERAL_HUGETLB
48 select ARCH_WANT_IPC_PARSE_VERSION
49 select ARCH_WANT_LD_ORPHAN_WARN
50 select BINFMT_FLAT_ARGVP_ENVP_ON_STACK
51 select BUILDTIME_TABLE_SORT if MMU
52 select COMMON_CLK if !(ARCH_RPC || ARCH_FOOTBRIDGE)
53 select CLONE_BACKWARDS
54 select CPU_PM if SUSPEND || CPU_IDLE
55 select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS
56 select DMA_DECLARE_COHERENT
57 select DMA_GLOBAL_POOL if !MMU
58 select DMA_NONCOHERENT_MMAP if MMU
59 select EDAC_SUPPORT
60 select EDAC_ATOMIC_SCRUB
61 select GENERIC_ALLOCATOR
62 select GENERIC_ARCH_TOPOLOGY if ARM_CPU_TOPOLOGY
63 select GENERIC_ATOMIC64 if CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI
64 select GENERIC_CLOCKEVENTS_BROADCAST if SMP
65 select GENERIC_IRQ_IPI if SMP
66 select GENERIC_CPU_AUTOPROBE
67 select GENERIC_CPU_DEVICES
68 select GENERIC_EARLY_IOREMAP
69 select GENERIC_IDLE_POLL_SETUP
70 select GENERIC_IRQ_MULTI_HANDLER
71 select GENERIC_IRQ_PROBE
72 select GENERIC_IRQ_SHOW
73 select GENERIC_IRQ_SHOW_LEVEL
74 select GENERIC_LIB_DEVMEM_IS_ALLOWED
75 select GENERIC_PCI_IOMAP
76 select GENERIC_SCHED_CLOCK
77 select GENERIC_SMP_IDLE_THREAD
78 select HARDIRQS_SW_RESEND
79 select HAS_IOPORT
80 select HAVE_ARCH_AUDITSYSCALL if AEABI && !OABI_COMPAT
81 select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
82 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
83 select HAVE_ARCH_KFENCE if MMU && !XIP_KERNEL
84 select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
85 select HAVE_ARCH_KASAN if MMU && !XIP_KERNEL
86 select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN
87 select HAVE_ARCH_MMAP_RND_BITS if MMU
88 select HAVE_ARCH_PFN_VALID
89 select HAVE_ARCH_SECCOMP
90 select HAVE_ARCH_SECCOMP_FILTER if AEABI && !OABI_COMPAT
91 select HAVE_ARCH_STACKLEAK
92 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
93 select HAVE_ARCH_TRACEHOOK
94 select HAVE_ARCH_TRANSPARENT_HUGEPAGE if ARM_LPAE
95 select HAVE_ARM_SMCCC if CPU_V7
96 select HAVE_EBPF_JIT if !CPU_ENDIAN_BE32
97 select HAVE_CONTEXT_TRACKING_USER
98 select HAVE_C_RECORDMCOUNT
99 select HAVE_BUILDTIME_MCOUNT_SORT
100 select HAVE_DEBUG_KMEMLEAK if !XIP_KERNEL
101 select HAVE_DMA_CONTIGUOUS if MMU
102 select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
103 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
104 select HAVE_EFFICIENT_UNALIGNED_ACCESS if (CPU_V6 || CPU_V6K || CPU_V7) && MMU
105 select HAVE_EXIT_THREAD
106 select HAVE_GUP_FAST if ARM_LPAE
107 select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
108 select HAVE_FUNCTION_ERROR_INJECTION
109 select HAVE_FUNCTION_GRAPH_TRACER
110 select HAVE_FUNCTION_TRACER if !XIP_KERNEL
111 select HAVE_GCC_PLUGINS
112 select HAVE_HW_BREAKPOINT if PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7)
113 select HAVE_IRQ_TIME_ACCOUNTING
114 select HAVE_KERNEL_GZIP
115 select HAVE_KERNEL_LZ4
116 select HAVE_KERNEL_LZMA
117 select HAVE_KERNEL_LZO
118 select HAVE_KERNEL_XZ
119 select HAVE_KPROBES if !XIP_KERNEL && !CPU_ENDIAN_BE32 && !CPU_V7M
120 select HAVE_KRETPROBES if HAVE_KPROBES
121 select HAVE_LD_DEAD_CODE_DATA_ELIMINATION if (LD_VERSION >= 23600 || LD_IS_LLD)
122 select HAVE_MOD_ARCH_SPECIFIC
123 select HAVE_NMI
124 select HAVE_OPTPROBES if !THUMB2_KERNEL
125 select HAVE_PAGE_SIZE_4KB
126 select HAVE_PCI if MMU
127 select HAVE_PERF_EVENTS
128 select HAVE_PERF_REGS
129 select HAVE_PERF_USER_STACK_DUMP
130 select MMU_GATHER_RCU_TABLE_FREE if SMP && ARM_LPAE
131 select HAVE_REGS_AND_STACK_ACCESS_API
132 select HAVE_RSEQ
133 select HAVE_STACKPROTECTOR
134 select HAVE_SYSCALL_TRACEPOINTS
135 select HAVE_UID16
136 select HAVE_VIRT_CPU_ACCOUNTING_GEN
137 select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU
138 select IRQ_FORCED_THREADING
139 select LOCK_MM_AND_FIND_VMA
140 select MODULES_USE_ELF_REL
141 select NEED_DMA_MAP_STATE
142 select OF_EARLY_FLATTREE if OF
143 select OLD_SIGACTION
144 select OLD_SIGSUSPEND3
145 select PCI_DOMAINS_GENERIC if PCI
146 select PCI_SYSCALL if PCI
147 select PERF_USE_VMALLOC
148 select RTC_LIB
149 select SPARSE_IRQ if !(ARCH_FOOTBRIDGE || ARCH_RPC)
150 select SYS_SUPPORTS_APM_EMULATION
151 select THREAD_INFO_IN_TASK
152 select TIMER_OF if OF
153 select HAVE_ARCH_VMAP_STACK if MMU && ARM_HAS_GROUP_RELOCS
154 select TRACE_IRQFLAGS_SUPPORT if !CPU_V7M
155 select USE_OF if !(ARCH_FOOTBRIDGE || ARCH_RPC || ARCH_SA1100)
156 # Above selects are sorted alphabetically; please add new ones
157 # according to that. Thanks.
158 help
159 The ARM series is a line of low-power-consumption RISC chip designs
160 licensed by ARM Ltd and targeted at embedded applications and
161 handhelds such as the Compaq IPAQ. ARM-based PCs are no longer
162 manufactured, but legacy ARM-based PC hardware remains popular in
163 Europe. There is an ARM Linux project with a web page at
164 <http://www.arm.linux.org.uk/>.
165
166config ARM_HAS_GROUP_RELOCS
167 def_bool y
168 depends on !LD_IS_LLD || LLD_VERSION >= 140000
169 depends on !COMPILE_TEST
170 help
171 Whether or not to use R_ARM_ALU_PC_Gn or R_ARM_LDR_PC_Gn group
172 relocations, which have been around for a long time, but were not
173 supported in LLD until version 14. The combined range is -/+ 256 MiB,
174 which is usually sufficient, but not for allyesconfig, so we disable
175 this feature when doing compile testing.
176
177config ARM_DMA_USE_IOMMU
178 bool
179 select NEED_SG_DMA_LENGTH
180
181if ARM_DMA_USE_IOMMU
182
183config ARM_DMA_IOMMU_ALIGNMENT
184 int "Maximum PAGE_SIZE order of alignment for DMA IOMMU buffers"
185 range 4 9
186 default 8
187 help
188 DMA mapping framework by default aligns all buffers to the smallest
189 PAGE_SIZE order which is greater than or equal to the requested buffer
190 size. This works well for buffers up to a few hundreds kilobytes, but
191 for larger buffers it just a waste of address space. Drivers which has
192 relatively small addressing window (like 64Mib) might run out of
193 virtual space with just a few allocations.
194
195 With this parameter you can specify the maximum PAGE_SIZE order for
196 DMA IOMMU buffers. Larger buffers will be aligned only to this
197 specified order. The order is expressed as a power of two multiplied
198 by the PAGE_SIZE.
199
200endif
201
202config SYS_SUPPORTS_APM_EMULATION
203 bool
204
205config HAVE_TCM
206 bool
207 select GENERIC_ALLOCATOR
208
209config HAVE_PROC_CPU
210 bool
211
212config NO_IOPORT_MAP
213 bool
214
215config SBUS
216 bool
217
218config STACKTRACE_SUPPORT
219 bool
220 default y
221
222config LOCKDEP_SUPPORT
223 bool
224 default y
225
226config ARCH_HAS_ILOG2_U32
227 bool
228
229config ARCH_HAS_ILOG2_U64
230 bool
231
232config ARCH_HAS_BANDGAP
233 bool
234
235config FIX_EARLYCON_MEM
236 def_bool y if MMU
237
238config GENERIC_HWEIGHT
239 bool
240 default y
241
242config GENERIC_CALIBRATE_DELAY
243 bool
244 default y
245
246config ARCH_MAY_HAVE_PC_FDC
247 bool
248
249config ARCH_SUPPORTS_UPROBES
250 def_bool y
251
252config GENERIC_ISA_DMA
253 bool
254
255config FIQ
256 bool
257
258config ARCH_MTD_XIP
259 bool
260
261config ARM_PATCH_PHYS_VIRT
262 bool "Patch physical to virtual translations at runtime" if !ARCH_MULTIPLATFORM
263 default y
264 depends on MMU
265 help
266 Patch phys-to-virt and virt-to-phys translation functions at
267 boot and module load time according to the position of the
268 kernel in system memory.
269
270 This can only be used with non-XIP MMU kernels where the base
271 of physical memory is at a 2 MiB boundary.
272
273 Only disable this option if you know that you do not require
274 this feature (eg, building a kernel for a single machine) and
275 you need to shrink the kernel to the minimal size.
276
277config NEED_MACH_IO_H
278 bool
279 help
280 Select this when mach/io.h is required to provide special
281 definitions for this platform. The need for mach/io.h should
282 be avoided when possible.
283
284config NEED_MACH_MEMORY_H
285 bool
286 help
287 Select this when mach/memory.h is required to provide special
288 definitions for this platform. The need for mach/memory.h should
289 be avoided when possible.
290
291config PHYS_OFFSET
292 hex "Physical address of main memory" if MMU
293 depends on !ARM_PATCH_PHYS_VIRT || !AUTO_ZRELADDR
294 default DRAM_BASE if !MMU
295 default 0x00000000 if ARCH_FOOTBRIDGE
296 default 0x10000000 if ARCH_OMAP1 || ARCH_RPC
297 default 0xa0000000 if ARCH_PXA
298 default 0xc0000000 if ARCH_EP93XX || ARCH_SA1100
299 default 0
300 help
301 Please provide the physical address corresponding to the
302 location of main memory in your system.
303
304config GENERIC_BUG
305 def_bool y
306 depends on BUG
307
308config PGTABLE_LEVELS
309 int
310 default 3 if ARM_LPAE
311 default 2
312
313menu "System Type"
314
315config MMU
316 bool "MMU-based Paged Memory Management Support"
317 default y
318 help
319 Select if you want MMU-based virtualised addressing space
320 support by paged memory management. If unsure, say 'Y'.
321
322config ARM_SINGLE_ARMV7M
323 def_bool !MMU
324 select ARM_NVIC
325 select CPU_V7M
326 select NO_IOPORT_MAP
327
328config ARCH_MMAP_RND_BITS_MIN
329 default 8
330
331config ARCH_MMAP_RND_BITS_MAX
332 default 14 if PAGE_OFFSET=0x40000000
333 default 15 if PAGE_OFFSET=0x80000000
334 default 16
335
336config ARCH_MULTIPLATFORM
337 bool "Require kernel to be portable to multiple machines" if EXPERT
338 depends on MMU && !(ARCH_FOOTBRIDGE || ARCH_RPC || ARCH_SA1100)
339 default y
340 help
341 In general, all Arm machines can be supported in a single
342 kernel image, covering either Armv4/v5 or Armv6/v7.
343
344 However, some configuration options require hardcoding machine
345 specific physical addresses or enable errata workarounds that may
346 break other machines.
347
348 Selecting N here allows using those options, including
349 DEBUG_UNCOMPRESS, XIP_KERNEL and ZBOOT_ROM. If unsure, say Y.
350
351source "arch/arm/Kconfig.platforms"
352
353#
354# This is sorted alphabetically by mach-* pathname. However, plat-*
355# Kconfigs may be included either alphabetically (according to the
356# plat- suffix) or along side the corresponding mach-* source.
357#
358source "arch/arm/mach-actions/Kconfig"
359
360source "arch/arm/mach-alpine/Kconfig"
361
362source "arch/arm/mach-artpec/Kconfig"
363
364source "arch/arm/mach-aspeed/Kconfig"
365
366source "arch/arm/mach-at91/Kconfig"
367
368source "arch/arm/mach-axxia/Kconfig"
369
370source "arch/arm/mach-bcm/Kconfig"
371
372source "arch/arm/mach-berlin/Kconfig"
373
374source "arch/arm/mach-clps711x/Kconfig"
375
376source "arch/arm/mach-davinci/Kconfig"
377
378source "arch/arm/mach-digicolor/Kconfig"
379
380source "arch/arm/mach-dove/Kconfig"
381
382source "arch/arm/mach-ep93xx/Kconfig"
383
384source "arch/arm/mach-exynos/Kconfig"
385
386source "arch/arm/mach-footbridge/Kconfig"
387
388source "arch/arm/mach-gemini/Kconfig"
389
390source "arch/arm/mach-highbank/Kconfig"
391
392source "arch/arm/mach-hisi/Kconfig"
393
394source "arch/arm/mach-hpe/Kconfig"
395
396source "arch/arm/mach-imx/Kconfig"
397
398source "arch/arm/mach-ixp4xx/Kconfig"
399
400source "arch/arm/mach-keystone/Kconfig"
401
402source "arch/arm/mach-lpc32xx/Kconfig"
403
404source "arch/arm/mach-mediatek/Kconfig"
405
406source "arch/arm/mach-meson/Kconfig"
407
408source "arch/arm/mach-milbeaut/Kconfig"
409
410source "arch/arm/mach-mmp/Kconfig"
411
412source "arch/arm/mach-mstar/Kconfig"
413
414source "arch/arm/mach-mv78xx0/Kconfig"
415
416source "arch/arm/mach-mvebu/Kconfig"
417
418source "arch/arm/mach-mxs/Kconfig"
419
420source "arch/arm/mach-nomadik/Kconfig"
421
422source "arch/arm/mach-npcm/Kconfig"
423
424source "arch/arm/mach-omap1/Kconfig"
425
426source "arch/arm/mach-omap2/Kconfig"
427
428source "arch/arm/mach-orion5x/Kconfig"
429
430source "arch/arm/mach-pxa/Kconfig"
431
432source "arch/arm/mach-qcom/Kconfig"
433
434source "arch/arm/mach-realtek/Kconfig"
435
436source "arch/arm/mach-rpc/Kconfig"
437
438source "arch/arm/mach-rockchip/Kconfig"
439
440source "arch/arm/mach-s3c/Kconfig"
441
442source "arch/arm/mach-s5pv210/Kconfig"
443
444source "arch/arm/mach-sa1100/Kconfig"
445
446source "arch/arm/mach-shmobile/Kconfig"
447
448source "arch/arm/mach-socfpga/Kconfig"
449
450source "arch/arm/mach-spear/Kconfig"
451
452source "arch/arm/mach-sti/Kconfig"
453
454source "arch/arm/mach-stm32/Kconfig"
455
456source "arch/arm/mach-sunxi/Kconfig"
457
458source "arch/arm/mach-tegra/Kconfig"
459
460source "arch/arm/mach-ux500/Kconfig"
461
462source "arch/arm/mach-versatile/Kconfig"
463
464source "arch/arm/mach-vt8500/Kconfig"
465
466source "arch/arm/mach-zynq/Kconfig"
467
468# ARMv7-M architecture
469config ARCH_LPC18XX
470 bool "NXP LPC18xx/LPC43xx"
471 depends on ARM_SINGLE_ARMV7M
472 select ARCH_HAS_RESET_CONTROLLER
473 select ARM_AMBA
474 select CLKSRC_LPC32XX
475 select PINCTRL
476 help
477 Support for NXP's LPC18xx Cortex-M3 and LPC43xx Cortex-M4
478 high performance microcontrollers.
479
480config ARCH_MPS2
481 bool "ARM MPS2 platform"
482 depends on ARM_SINGLE_ARMV7M
483 select ARM_AMBA
484 select CLKSRC_MPS2
485 help
486 Support for Cortex-M Prototyping System (or V2M-MPS2) which comes
487 with a range of available cores like Cortex-M3/M4/M7.
488
489 Please, note that depends which Application Note is used memory map
490 for the platform may vary, so adjustment of RAM base might be needed.
491
492# Definitions to make life easier
493config ARCH_ACORN
494 bool
495
496config PLAT_ORION
497 bool
498 select CLKSRC_MMIO
499 select GENERIC_IRQ_CHIP
500 select IRQ_DOMAIN
501
502config PLAT_ORION_LEGACY
503 bool
504 select PLAT_ORION
505
506config PLAT_VERSATILE
507 bool
508
509source "arch/arm/mm/Kconfig"
510
511config IWMMXT
512 bool "Enable iWMMXt support"
513 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK
514 default y if PXA27x || PXA3xx || ARCH_MMP
515 help
516 Enable support for iWMMXt context switching at run time if
517 running on a CPU that supports it.
518
519if !MMU
520source "arch/arm/Kconfig-nommu"
521endif
522
523config PJ4B_ERRATA_4742
524 bool "PJ4B Errata 4742: IDLE Wake Up Commands can Cause the CPU Core to Cease Operation"
525 depends on CPU_PJ4B && MACH_ARMADA_370
526 default y
527 help
528 When coming out of either a Wait for Interrupt (WFI) or a Wait for
529 Event (WFE) IDLE states, a specific timing sensitivity exists between
530 the retiring WFI/WFE instructions and the newly issued subsequent
531 instructions. This sensitivity can result in a CPU hang scenario.
532 Workaround:
533 The software must insert either a Data Synchronization Barrier (DSB)
534 or Data Memory Barrier (DMB) command immediately after the WFI/WFE
535 instruction
536
537config ARM_ERRATA_326103
538 bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory"
539 depends on CPU_V6
540 help
541 Executing a SWP instruction to read-only memory does not set bit 11
542 of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to
543 treat the access as a read, preventing a COW from occurring and
544 causing the faulting task to livelock.
545
546config ARM_ERRATA_411920
547 bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
548 depends on CPU_V6 || CPU_V6K
549 help
550 Invalidation of the Instruction Cache operation can
551 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
552 It does not affect the MPCore. This option enables the ARM Ltd.
553 recommended workaround.
554
555config ARM_ERRATA_430973
556 bool "ARM errata: Stale prediction on replaced interworking branch"
557 depends on CPU_V7
558 help
559 This option enables the workaround for the 430973 Cortex-A8
560 r1p* erratum. If a code sequence containing an ARM/Thumb
561 interworking branch is replaced with another code sequence at the
562 same virtual address, whether due to self-modifying code or virtual
563 to physical address re-mapping, Cortex-A8 does not recover from the
564 stale interworking branch prediction. This results in Cortex-A8
565 executing the new code sequence in the incorrect ARM or Thumb state.
566 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
567 and also flushes the branch target cache at every context switch.
568 Note that setting specific bits in the ACTLR register may not be
569 available in non-secure mode.
570
571config ARM_ERRATA_458693
572 bool "ARM errata: Processor deadlock when a false hazard is created"
573 depends on CPU_V7
574 depends on !ARCH_MULTIPLATFORM
575 help
576 This option enables the workaround for the 458693 Cortex-A8 (r2p0)
577 erratum. For very specific sequences of memory operations, it is
578 possible for a hazard condition intended for a cache line to instead
579 be incorrectly associated with a different cache line. This false
580 hazard might then cause a processor deadlock. The workaround enables
581 the L1 caching of the NEON accesses and disables the PLD instruction
582 in the ACTLR register. Note that setting specific bits in the ACTLR
583 register may not be available in non-secure mode and thus is not
584 available on a multiplatform kernel. This should be applied by the
585 bootloader instead.
586
587config ARM_ERRATA_460075
588 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
589 depends on CPU_V7
590 depends on !ARCH_MULTIPLATFORM
591 help
592 This option enables the workaround for the 460075 Cortex-A8 (r2p0)
593 erratum. Any asynchronous access to the L2 cache may encounter a
594 situation in which recent store transactions to the L2 cache are lost
595 and overwritten with stale memory contents from external memory. The
596 workaround disables the write-allocate mode for the L2 cache via the
597 ACTLR register. Note that setting specific bits in the ACTLR register
598 may not be available in non-secure mode and thus is not available on
599 a multiplatform kernel. This should be applied by the bootloader
600 instead.
601
602config ARM_ERRATA_742230
603 bool "ARM errata: DMB operation may be faulty"
604 depends on CPU_V7 && SMP
605 depends on !ARCH_MULTIPLATFORM
606 help
607 This option enables the workaround for the 742230 Cortex-A9
608 (r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction
609 between two write operations may not ensure the correct visibility
610 ordering of the two writes. This workaround sets a specific bit in
611 the diagnostic register of the Cortex-A9 which causes the DMB
612 instruction to behave as a DSB, ensuring the correct behaviour of
613 the two writes. Note that setting specific bits in the diagnostics
614 register may not be available in non-secure mode and thus is not
615 available on a multiplatform kernel. This should be applied by the
616 bootloader instead.
617
618config ARM_ERRATA_742231
619 bool "ARM errata: Incorrect hazard handling in the SCU may lead to data corruption"
620 depends on CPU_V7 && SMP
621 depends on !ARCH_MULTIPLATFORM
622 help
623 This option enables the workaround for the 742231 Cortex-A9
624 (r2p0..r2p2) erratum. Under certain conditions, specific to the
625 Cortex-A9 MPCore micro-architecture, two CPUs working in SMP mode,
626 accessing some data located in the same cache line, may get corrupted
627 data due to bad handling of the address hazard when the line gets
628 replaced from one of the CPUs at the same time as another CPU is
629 accessing it. This workaround sets specific bits in the diagnostic
630 register of the Cortex-A9 which reduces the linefill issuing
631 capabilities of the processor. Note that setting specific bits in the
632 diagnostics register may not be available in non-secure mode and thus
633 is not available on a multiplatform kernel. This should be applied by
634 the bootloader instead.
635
636config ARM_ERRATA_643719
637 bool "ARM errata: LoUIS bit field in CLIDR register is incorrect"
638 depends on CPU_V7 && SMP
639 default y
640 help
641 This option enables the workaround for the 643719 Cortex-A9 (prior to
642 r1p0) erratum. On affected cores the LoUIS bit field of the CLIDR
643 register returns zero when it should return one. The workaround
644 corrects this value, ensuring cache maintenance operations which use
645 it behave as intended and avoiding data corruption.
646
647config ARM_ERRATA_720789
648 bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID"
649 depends on CPU_V7
650 help
651 This option enables the workaround for the 720789 Cortex-A9 (prior to
652 r2p0) erratum. A faulty ASID can be sent to the other CPUs for the
653 broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS.
654 As a consequence of this erratum, some TLB entries which should be
655 invalidated are not, resulting in an incoherency in the system page
656 tables. The workaround changes the TLB flushing routines to invalidate
657 entries regardless of the ASID.
658
659config ARM_ERRATA_743622
660 bool "ARM errata: Faulty hazard checking in the Store Buffer may lead to data corruption"
661 depends on CPU_V7
662 depends on !ARCH_MULTIPLATFORM
663 help
664 This option enables the workaround for the 743622 Cortex-A9
665 (r2p*) erratum. Under very rare conditions, a faulty
666 optimisation in the Cortex-A9 Store Buffer may lead to data
667 corruption. This workaround sets a specific bit in the diagnostic
668 register of the Cortex-A9 which disables the Store Buffer
669 optimisation, preventing the defect from occurring. This has no
670 visible impact on the overall performance or power consumption of the
671 processor. Note that setting specific bits in the diagnostics register
672 may not be available in non-secure mode and thus is not available on a
673 multiplatform kernel. This should be applied by the bootloader instead.
674
675config ARM_ERRATA_751472
676 bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation"
677 depends on CPU_V7
678 depends on !ARCH_MULTIPLATFORM
679 help
680 This option enables the workaround for the 751472 Cortex-A9 (prior
681 to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the
682 completion of a following broadcasted operation if the second
683 operation is received by a CPU before the ICIALLUIS has completed,
684 potentially leading to corrupted entries in the cache or TLB.
685 Note that setting specific bits in the diagnostics register may
686 not be available in non-secure mode and thus is not available on
687 a multiplatform kernel. This should be applied by the bootloader
688 instead.
689
690config ARM_ERRATA_754322
691 bool "ARM errata: possible faulty MMU translations following an ASID switch"
692 depends on CPU_V7
693 help
694 This option enables the workaround for the 754322 Cortex-A9 (r2p*,
695 r3p*) erratum. A speculative memory access may cause a page table walk
696 which starts prior to an ASID switch but completes afterwards. This
697 can populate the micro-TLB with a stale entry which may be hit with
698 the new ASID. This workaround places two dsb instructions in the mm
699 switching code so that no page table walks can cross the ASID switch.
700
701config ARM_ERRATA_754327
702 bool "ARM errata: no automatic Store Buffer drain"
703 depends on CPU_V7 && SMP
704 help
705 This option enables the workaround for the 754327 Cortex-A9 (prior to
706 r2p0) erratum. The Store Buffer does not have any automatic draining
707 mechanism and therefore a livelock may occur if an external agent
708 continuously polls a memory location waiting to observe an update.
709 This workaround defines cpu_relax() as smp_mb(), preventing correctly
710 written polling loops from denying visibility of updates to memory.
711
712config ARM_ERRATA_364296
713 bool "ARM errata: Possible cache data corruption with hit-under-miss enabled"
714 depends on CPU_V6
715 help
716 This options enables the workaround for the 364296 ARM1136
717 r0p2 erratum (possible cache data corruption with
718 hit-under-miss enabled). It sets the undocumented bit 31 in
719 the auxiliary control register and the FI bit in the control
720 register, thus disabling hit-under-miss without putting the
721 processor into full low interrupt latency mode. ARM11MPCore
722 is not affected.
723
724config ARM_ERRATA_764369
725 bool "ARM errata: Data cache line maintenance operation by MVA may not succeed"
726 depends on CPU_V7 && SMP
727 help
728 This option enables the workaround for erratum 764369
729 affecting Cortex-A9 MPCore with two or more processors (all
730 current revisions). Under certain timing circumstances, a data
731 cache line maintenance operation by MVA targeting an Inner
732 Shareable memory region may fail to proceed up to either the
733 Point of Coherency or to the Point of Unification of the
734 system. This workaround adds a DSB instruction before the
735 relevant cache maintenance functions and sets a specific bit
736 in the diagnostic control register of the SCU.
737
738config ARM_ERRATA_764319
739 bool "ARM errata: Read to DBGPRSR and DBGOSLSR may generate Undefined instruction"
740 depends on CPU_V7
741 help
742 This option enables the workaround for the 764319 Cortex-A9 erratum.
743 CP14 read accesses to the DBGPRSR and DBGOSLSR registers generate an
744 unexpected Undefined Instruction exception when the DBGSWENABLE
745 external pin is set to 0, even when the CP14 accesses are performed
746 from a privileged mode. This work around catches the exception in a
747 way the kernel does not stop execution.
748
749config ARM_ERRATA_775420
750 bool "ARM errata: A data cache maintenance operation which aborts, might lead to deadlock"
751 depends on CPU_V7
752 help
753 This option enables the workaround for the 775420 Cortex-A9 (r2p2,
754 r2p6,r2p8,r2p10,r3p0) erratum. In case a data cache maintenance
755 operation aborts with MMU exception, it might cause the processor
756 to deadlock. This workaround puts DSB before executing ISB if
757 an abort may occur on cache maintenance.
758
759config ARM_ERRATA_798181
760 bool "ARM errata: TLBI/DSB failure on Cortex-A15"
761 depends on CPU_V7 && SMP
762 help
763 On Cortex-A15 (r0p0..r3p2) the TLBI*IS/DSB operations are not
764 adequately shooting down all use of the old entries. This
765 option enables the Linux kernel workaround for this erratum
766 which sends an IPI to the CPUs that are running the same ASID
767 as the one being invalidated.
768
769config ARM_ERRATA_773022
770 bool "ARM errata: incorrect instructions may be executed from loop buffer"
771 depends on CPU_V7
772 help
773 This option enables the workaround for the 773022 Cortex-A15
774 (up to r0p4) erratum. In certain rare sequences of code, the
775 loop buffer may deliver incorrect instructions. This
776 workaround disables the loop buffer to avoid the erratum.
777
778config ARM_ERRATA_818325_852422
779 bool "ARM errata: A12: some seqs of opposed cond code instrs => deadlock or corruption"
780 depends on CPU_V7
781 help
782 This option enables the workaround for:
783 - Cortex-A12 818325: Execution of an UNPREDICTABLE STR or STM
784 instruction might deadlock. Fixed in r0p1.
785 - Cortex-A12 852422: Execution of a sequence of instructions might
786 lead to either a data corruption or a CPU deadlock. Not fixed in
787 any Cortex-A12 cores yet.
788 This workaround for all both errata involves setting bit[12] of the
789 Feature Register. This bit disables an optimisation applied to a
790 sequence of 2 instructions that use opposing condition codes.
791
792config ARM_ERRATA_821420
793 bool "ARM errata: A12: sequence of VMOV to core registers might lead to a dead lock"
794 depends on CPU_V7
795 help
796 This option enables the workaround for the 821420 Cortex-A12
797 (all revs) erratum. In very rare timing conditions, a sequence
798 of VMOV to Core registers instructions, for which the second
799 one is in the shadow of a branch or abort, can lead to a
800 deadlock when the VMOV instructions are issued out-of-order.
801
802config ARM_ERRATA_825619
803 bool "ARM errata: A12: DMB NSHST/ISHST mixed ... might cause deadlock"
804 depends on CPU_V7
805 help
806 This option enables the workaround for the 825619 Cortex-A12
807 (all revs) erratum. Within rare timing constraints, executing a
808 DMB NSHST or DMB ISHST instruction followed by a mix of Cacheable
809 and Device/Strongly-Ordered loads and stores might cause deadlock
810
811config ARM_ERRATA_857271
812 bool "ARM errata: A12: CPU might deadlock under some very rare internal conditions"
813 depends on CPU_V7
814 help
815 This option enables the workaround for the 857271 Cortex-A12
816 (all revs) erratum. Under very rare timing conditions, the CPU might
817 hang. The workaround is expected to have a < 1% performance impact.
818
819config ARM_ERRATA_852421
820 bool "ARM errata: A17: DMB ST might fail to create order between stores"
821 depends on CPU_V7
822 help
823 This option enables the workaround for the 852421 Cortex-A17
824 (r1p0, r1p1, r1p2) erratum. Under very rare timing conditions,
825 execution of a DMB ST instruction might fail to properly order
826 stores from GroupA and stores from GroupB.
827
828config ARM_ERRATA_852423
829 bool "ARM errata: A17: some seqs of opposed cond code instrs => deadlock or corruption"
830 depends on CPU_V7
831 help
832 This option enables the workaround for:
833 - Cortex-A17 852423: Execution of a sequence of instructions might
834 lead to either a data corruption or a CPU deadlock. Not fixed in
835 any Cortex-A17 cores yet.
836 This is identical to Cortex-A12 erratum 852422. It is a separate
837 config option from the A12 erratum due to the way errata are checked
838 for and handled.
839
840config ARM_ERRATA_857272
841 bool "ARM errata: A17: CPU might deadlock under some very rare internal conditions"
842 depends on CPU_V7
843 help
844 This option enables the workaround for the 857272 Cortex-A17 erratum.
845 This erratum is not known to be fixed in any A17 revision.
846 This is identical to Cortex-A12 erratum 857271. It is a separate
847 config option from the A12 erratum due to the way errata are checked
848 for and handled.
849
850endmenu
851
852source "arch/arm/common/Kconfig"
853
854menu "Bus support"
855
856config ISA
857 bool
858 help
859 Find out whether you have ISA slots on your motherboard. ISA is the
860 name of a bus system, i.e. the way the CPU talks to the other stuff
861 inside your box. Other bus systems are PCI, EISA, MicroChannel
862 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
863 newer boards don't support it. If you have ISA, say Y, otherwise N.
864
865# Select ISA DMA interface
866config ISA_DMA_API
867 bool
868
869config ARM_ERRATA_814220
870 bool "ARM errata: Cache maintenance by set/way operations can execute out of order"
871 depends on CPU_V7
872 help
873 The v7 ARM states that all cache and branch predictor maintenance
874 operations that do not specify an address execute, relative to
875 each other, in program order.
876 However, because of this erratum, an L2 set/way cache maintenance
877 operation can overtake an L1 set/way cache maintenance operation.
878 This ERRATA only affected the Cortex-A7 and present in r0p2, r0p3,
879 r0p4, r0p5.
880
881endmenu
882
883menu "Kernel Features"
884
885config HAVE_SMP
886 bool
887 help
888 This option should be selected by machines which have an SMP-
889 capable CPU.
890
891 The only effect of this option is to make the SMP-related
892 options available to the user for configuration.
893
894config SMP
895 bool "Symmetric Multi-Processing"
896 depends on CPU_V6K || CPU_V7
897 depends on HAVE_SMP
898 depends on MMU || ARM_MPU
899 select IRQ_WORK
900 help
901 This enables support for systems with more than one CPU. If you have
902 a system with only one CPU, say N. If you have a system with more
903 than one CPU, say Y.
904
905 If you say N here, the kernel will run on uni- and multiprocessor
906 machines, but will use only one CPU of a multiprocessor machine. If
907 you say Y here, the kernel will run on many, but not all,
908 uniprocessor machines. On a uniprocessor machine, the kernel
909 will run faster if you say N here.
910
911 See also <file:Documentation/arch/x86/i386/IO-APIC.rst>,
912 <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at
913 <http://tldp.org/HOWTO/SMP-HOWTO.html>.
914
915 If you don't know what to do here, say N.
916
917config SMP_ON_UP
918 bool "Allow booting SMP kernel on uniprocessor systems"
919 depends on SMP && MMU
920 default y
921 help
922 SMP kernels contain instructions which fail on non-SMP processors.
923 Enabling this option allows the kernel to modify itself to make
924 these instructions safe. Disabling it allows about 1K of space
925 savings.
926
927 If you don't know what to do here, say Y.
928
929
930config CURRENT_POINTER_IN_TPIDRURO
931 def_bool y
932 depends on CPU_32v6K && !CPU_V6
933
934config IRQSTACKS
935 def_bool y
936 select HAVE_IRQ_EXIT_ON_IRQ_STACK
937 select HAVE_SOFTIRQ_ON_OWN_STACK
938
939config ARM_CPU_TOPOLOGY
940 bool "Support cpu topology definition"
941 depends on SMP && CPU_V7
942 default y
943 help
944 Support ARM cpu topology definition. The MPIDR register defines
945 affinity between processors which is then used to describe the cpu
946 topology of an ARM System.
947
948config SCHED_MC
949 bool "Multi-core scheduler support"
950 depends on ARM_CPU_TOPOLOGY
951 help
952 Multi-core scheduler support improves the CPU scheduler's decision
953 making when dealing with multi-core CPU chips at a cost of slightly
954 increased overhead in some places. If unsure say N here.
955
956config SCHED_SMT
957 bool "SMT scheduler support"
958 depends on ARM_CPU_TOPOLOGY
959 help
960 Improves the CPU scheduler's decision making when dealing with
961 MultiThreading at a cost of slightly increased overhead in some
962 places. If unsure say N here.
963
964config HAVE_ARM_SCU
965 bool
966 help
967 This option enables support for the ARM snoop control unit
968
969config HAVE_ARM_ARCH_TIMER
970 bool "Architected timer support"
971 depends on CPU_V7
972 select ARM_ARCH_TIMER
973 help
974 This option enables support for the ARM architected timer
975
976config HAVE_ARM_TWD
977 bool
978 help
979 This options enables support for the ARM timer and watchdog unit
980
981config MCPM
982 bool "Multi-Cluster Power Management"
983 depends on CPU_V7 && SMP
984 help
985 This option provides the common power management infrastructure
986 for (multi-)cluster based systems, such as big.LITTLE based
987 systems.
988
989config MCPM_QUAD_CLUSTER
990 bool
991 depends on MCPM
992 help
993 To avoid wasting resources unnecessarily, MCPM only supports up
994 to 2 clusters by default.
995 Platforms with 3 or 4 clusters that use MCPM must select this
996 option to allow the additional clusters to be managed.
997
998config BIG_LITTLE
999 bool "big.LITTLE support (Experimental)"
1000 depends on CPU_V7 && SMP
1001 select MCPM
1002 help
1003 This option enables support selections for the big.LITTLE
1004 system architecture.
1005
1006config BL_SWITCHER
1007 bool "big.LITTLE switcher support"
1008 depends on BIG_LITTLE && MCPM && HOTPLUG_CPU && ARM_GIC
1009 select CPU_PM
1010 help
1011 The big.LITTLE "switcher" provides the core functionality to
1012 transparently handle transition between a cluster of A15's
1013 and a cluster of A7's in a big.LITTLE system.
1014
1015config BL_SWITCHER_DUMMY_IF
1016 tristate "Simple big.LITTLE switcher user interface"
1017 depends on BL_SWITCHER && DEBUG_KERNEL
1018 help
1019 This is a simple and dummy char dev interface to control
1020 the big.LITTLE switcher core code. It is meant for
1021 debugging purposes only.
1022
1023choice
1024 prompt "Memory split"
1025 depends on MMU
1026 default VMSPLIT_3G
1027 help
1028 Select the desired split between kernel and user memory.
1029
1030 If you are not absolutely sure what you are doing, leave this
1031 option alone!
1032
1033 config VMSPLIT_3G
1034 bool "3G/1G user/kernel split"
1035 config VMSPLIT_3G_OPT
1036 depends on !ARM_LPAE
1037 bool "3G/1G user/kernel split (for full 1G low memory)"
1038 config VMSPLIT_2G
1039 bool "2G/2G user/kernel split"
1040 config VMSPLIT_1G
1041 bool "1G/3G user/kernel split"
1042endchoice
1043
1044config PAGE_OFFSET
1045 hex
1046 default PHYS_OFFSET if !MMU
1047 default 0x40000000 if VMSPLIT_1G
1048 default 0x80000000 if VMSPLIT_2G
1049 default 0xB0000000 if VMSPLIT_3G_OPT
1050 default 0xC0000000
1051
1052config KASAN_SHADOW_OFFSET
1053 hex
1054 depends on KASAN
1055 default 0x1f000000 if PAGE_OFFSET=0x40000000
1056 default 0x5f000000 if PAGE_OFFSET=0x80000000
1057 default 0x9f000000 if PAGE_OFFSET=0xC0000000
1058 default 0x8f000000 if PAGE_OFFSET=0xB0000000
1059 default 0xffffffff
1060
1061config NR_CPUS
1062 int "Maximum number of CPUs (2-32)"
1063 range 2 16 if DEBUG_KMAP_LOCAL
1064 range 2 32 if !DEBUG_KMAP_LOCAL
1065 depends on SMP
1066 default "4"
1067 help
1068 The maximum number of CPUs that the kernel can support.
1069 Up to 32 CPUs can be supported, or up to 16 if kmap_local()
1070 debugging is enabled, which uses half of the per-CPU fixmap
1071 slots as guard regions.
1072
1073config HOTPLUG_CPU
1074 bool "Support for hot-pluggable CPUs"
1075 depends on SMP
1076 select GENERIC_IRQ_MIGRATION
1077 help
1078 Say Y here to experiment with turning CPUs off and on. CPUs
1079 can be controlled through /sys/devices/system/cpu.
1080
1081config ARM_PSCI
1082 bool "Support for the ARM Power State Coordination Interface (PSCI)"
1083 depends on HAVE_ARM_SMCCC
1084 select ARM_PSCI_FW
1085 help
1086 Say Y here if you want Linux to communicate with system firmware
1087 implementing the PSCI specification for CPU-centric power
1088 management operations described in ARM document number ARM DEN
1089 0022A ("Power State Coordination Interface System Software on
1090 ARM processors").
1091
1092config HZ_FIXED
1093 int
1094 default 128 if SOC_AT91RM9200
1095 default 0
1096
1097choice
1098 depends on HZ_FIXED = 0
1099 prompt "Timer frequency"
1100
1101config HZ_100
1102 bool "100 Hz"
1103
1104config HZ_200
1105 bool "200 Hz"
1106
1107config HZ_250
1108 bool "250 Hz"
1109
1110config HZ_300
1111 bool "300 Hz"
1112
1113config HZ_500
1114 bool "500 Hz"
1115
1116config HZ_1000
1117 bool "1000 Hz"
1118
1119endchoice
1120
1121config HZ
1122 int
1123 default HZ_FIXED if HZ_FIXED != 0
1124 default 100 if HZ_100
1125 default 200 if HZ_200
1126 default 250 if HZ_250
1127 default 300 if HZ_300
1128 default 500 if HZ_500
1129 default 1000
1130
1131config SCHED_HRTICK
1132 def_bool HIGH_RES_TIMERS
1133
1134config THUMB2_KERNEL
1135 bool "Compile the kernel in Thumb-2 mode" if !CPU_THUMBONLY
1136 depends on (CPU_V7 || CPU_V7M) && !CPU_V6 && !CPU_V6K
1137 default y if CPU_THUMBONLY
1138 select ARM_UNWIND
1139 help
1140 By enabling this option, the kernel will be compiled in
1141 Thumb-2 mode.
1142
1143 If unsure, say N.
1144
1145config ARM_PATCH_IDIV
1146 bool "Runtime patch udiv/sdiv instructions into __aeabi_{u}idiv()"
1147 depends on CPU_32v7
1148 default y
1149 help
1150 The ARM compiler inserts calls to __aeabi_idiv() and
1151 __aeabi_uidiv() when it needs to perform division on signed
1152 and unsigned integers. Some v7 CPUs have support for the sdiv
1153 and udiv instructions that can be used to implement those
1154 functions.
1155
1156 Enabling this option allows the kernel to modify itself to
1157 replace the first two instructions of these library functions
1158 with the sdiv or udiv plus "bx lr" instructions when the CPU
1159 it is running on supports them. Typically this will be faster
1160 and less power intensive than running the original library
1161 code to do integer division.
1162
1163config AEABI
1164 bool "Use the ARM EABI to compile the kernel" if !CPU_V7 && \
1165 !CPU_V7M && !CPU_V6 && !CPU_V6K && !CC_IS_CLANG
1166 default CPU_V7 || CPU_V7M || CPU_V6 || CPU_V6K || CC_IS_CLANG
1167 help
1168 This option allows for the kernel to be compiled using the latest
1169 ARM ABI (aka EABI). This is only useful if you are using a user
1170 space environment that is also compiled with EABI.
1171
1172 Since there are major incompatibilities between the legacy ABI and
1173 EABI, especially with regard to structure member alignment, this
1174 option also changes the kernel syscall calling convention to
1175 disambiguate both ABIs and allow for backward compatibility support
1176 (selected with CONFIG_OABI_COMPAT).
1177
1178 To use this you need GCC version 4.0.0 or later.
1179
1180config OABI_COMPAT
1181 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1182 depends on AEABI && !THUMB2_KERNEL
1183 help
1184 This option preserves the old syscall interface along with the
1185 new (ARM EABI) one. It also provides a compatibility layer to
1186 intercept syscalls that have structure arguments which layout
1187 in memory differs between the legacy ABI and the new ARM EABI
1188 (only for non "thumb" binaries). This option adds a tiny
1189 overhead to all syscalls and produces a slightly larger kernel.
1190
1191 The seccomp filter system will not be available when this is
1192 selected, since there is no way yet to sensibly distinguish
1193 between calling conventions during filtering.
1194
1195 If you know you'll be using only pure EABI user space then you
1196 can say N here. If this option is not selected and you attempt
1197 to execute a legacy ABI binary then the result will be
1198 UNPREDICTABLE (in fact it can be predicted that it won't work
1199 at all). If in doubt say N.
1200
1201config ARCH_SELECT_MEMORY_MODEL
1202 def_bool y
1203
1204config ARCH_FLATMEM_ENABLE
1205 def_bool !(ARCH_RPC || ARCH_SA1100)
1206
1207config ARCH_SPARSEMEM_ENABLE
1208 def_bool !ARCH_FOOTBRIDGE
1209 select SPARSEMEM_STATIC if SPARSEMEM
1210
1211config HIGHMEM
1212 bool "High Memory Support"
1213 depends on MMU
1214 select KMAP_LOCAL
1215 select KMAP_LOCAL_NON_LINEAR_PTE_ARRAY
1216 help
1217 The address space of ARM processors is only 4 Gigabytes large
1218 and it has to accommodate user address space, kernel address
1219 space as well as some memory mapped IO. That means that, if you
1220 have a large amount of physical memory and/or IO, not all of the
1221 memory can be "permanently mapped" by the kernel. The physical
1222 memory that is not permanently mapped is called "high memory".
1223
1224 Depending on the selected kernel/user memory split, minimum
1225 vmalloc space and actual amount of RAM, you may not need this
1226 option which should result in a slightly faster kernel.
1227
1228 If unsure, say n.
1229
1230config HIGHPTE
1231 bool "Allocate 2nd-level pagetables from highmem" if EXPERT
1232 depends on HIGHMEM
1233 default y
1234 help
1235 The VM uses one page of physical memory for each page table.
1236 For systems with a lot of processes, this can use a lot of
1237 precious low memory, eventually leading to low memory being
1238 consumed by page tables. Setting this option will allow
1239 user-space 2nd level page tables to reside in high memory.
1240
1241config ARM_PAN
1242 bool "Enable privileged no-access"
1243 depends on MMU
1244 default y
1245 help
1246 Increase kernel security by ensuring that normal kernel accesses
1247 are unable to access userspace addresses. This can help prevent
1248 use-after-free bugs becoming an exploitable privilege escalation
1249 by ensuring that magic values (such as LIST_POISON) will always
1250 fault when dereferenced.
1251
1252 The implementation uses CPU domains when !CONFIG_ARM_LPAE and
1253 disabling of TTBR0 page table walks with CONFIG_ARM_LPAE.
1254
1255config CPU_SW_DOMAIN_PAN
1256 def_bool y
1257 depends on ARM_PAN && !ARM_LPAE
1258 help
1259 Enable use of CPU domains to implement privileged no-access.
1260
1261 CPUs with low-vector mappings use a best-efforts implementation.
1262 Their lower 1MB needs to remain accessible for the vectors, but
1263 the remainder of userspace will become appropriately inaccessible.
1264
1265config CPU_TTBR0_PAN
1266 def_bool y
1267 depends on ARM_PAN && ARM_LPAE
1268 help
1269 Enable privileged no-access by disabling TTBR0 page table walks when
1270 running in kernel mode.
1271
1272config HW_PERF_EVENTS
1273 def_bool y
1274 depends on ARM_PMU
1275
1276config ARM_MODULE_PLTS
1277 bool "Use PLTs to allow module memory to spill over into vmalloc area"
1278 depends on MODULES
1279 select KASAN_VMALLOC if KASAN
1280 default y
1281 help
1282 Allocate PLTs when loading modules so that jumps and calls whose
1283 targets are too far away for their relative offsets to be encoded
1284 in the instructions themselves can be bounced via veneers in the
1285 module's PLT. This allows modules to be allocated in the generic
1286 vmalloc area after the dedicated module memory area has been
1287 exhausted. The modules will use slightly more memory, but after
1288 rounding up to page size, the actual memory footprint is usually
1289 the same.
1290
1291 Disabling this is usually safe for small single-platform
1292 configurations. If unsure, say y.
1293
1294config ARCH_FORCE_MAX_ORDER
1295 int "Order of maximal physically contiguous allocations"
1296 default "11" if SOC_AM33XX
1297 default "8" if SA1111
1298 default "10"
1299 help
1300 The kernel page allocator limits the size of maximal physically
1301 contiguous allocations. The limit is called MAX_PAGE_ORDER and it
1302 defines the maximal power of two of number of pages that can be
1303 allocated as a single contiguous block. This option allows
1304 overriding the default setting when ability to allocate very
1305 large blocks of physically contiguous memory is required.
1306
1307 Don't change if unsure.
1308
1309config ALIGNMENT_TRAP
1310 def_bool CPU_CP15_MMU
1311 select HAVE_PROC_CPU if PROC_FS
1312 help
1313 ARM processors cannot fetch/store information which is not
1314 naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1315 address divisible by 4. On 32-bit ARM processors, these non-aligned
1316 fetch/store instructions will be emulated in software if you say
1317 here, which has a severe performance impact. This is necessary for
1318 correct operation of some network protocols. With an IP-only
1319 configuration it is safe to say N, otherwise say Y.
1320
1321config UACCESS_WITH_MEMCPY
1322 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user()"
1323 depends on MMU
1324 default y if CPU_FEROCEON
1325 help
1326 Implement faster copy_to_user and clear_user methods for CPU
1327 cores where a 8-word STM instruction give significantly higher
1328 memory write throughput than a sequence of individual 32bit stores.
1329
1330 A possible side effect is a slight increase in scheduling latency
1331 between threads sharing the same address space if they invoke
1332 such copy operations with large buffers.
1333
1334 However, if the CPU data cache is using a write-allocate mode,
1335 this option is unlikely to provide any performance gain.
1336
1337config PARAVIRT
1338 bool "Enable paravirtualization code"
1339 help
1340 This changes the kernel so it can modify itself when it is run
1341 under a hypervisor, potentially improving performance significantly
1342 over full virtualization.
1343
1344config PARAVIRT_TIME_ACCOUNTING
1345 bool "Paravirtual steal time accounting"
1346 select PARAVIRT
1347 help
1348 Select this option to enable fine granularity task steal time
1349 accounting. Time spent executing other tasks in parallel with
1350 the current vCPU is discounted from the vCPU power. To account for
1351 that, there can be a small performance impact.
1352
1353 If in doubt, say N here.
1354
1355config XEN_DOM0
1356 def_bool y
1357 depends on XEN
1358
1359config XEN
1360 bool "Xen guest support on ARM"
1361 depends on ARM && AEABI && OF
1362 depends on CPU_V7 && !CPU_V6
1363 depends on !GENERIC_ATOMIC64
1364 depends on MMU
1365 select ARCH_DMA_ADDR_T_64BIT
1366 select ARM_PSCI
1367 select SWIOTLB
1368 select SWIOTLB_XEN
1369 select PARAVIRT
1370 help
1371 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
1372
1373config CC_HAVE_STACKPROTECTOR_TLS
1374 def_bool $(cc-option,-mtp=cp15 -mstack-protector-guard=tls -mstack-protector-guard-offset=0)
1375
1376config STACKPROTECTOR_PER_TASK
1377 bool "Use a unique stack canary value for each task"
1378 depends on STACKPROTECTOR && CURRENT_POINTER_IN_TPIDRURO && !XIP_DEFLATED_DATA
1379 depends on GCC_PLUGINS || CC_HAVE_STACKPROTECTOR_TLS
1380 select GCC_PLUGIN_ARM_SSP_PER_TASK if !CC_HAVE_STACKPROTECTOR_TLS
1381 default y
1382 help
1383 Due to the fact that GCC uses an ordinary symbol reference from
1384 which to load the value of the stack canary, this value can only
1385 change at reboot time on SMP systems, and all tasks running in the
1386 kernel's address space are forced to use the same canary value for
1387 the entire duration that the system is up.
1388
1389 Enable this option to switch to a different method that uses a
1390 different canary value for each task.
1391
1392endmenu
1393
1394menu "Boot options"
1395
1396config USE_OF
1397 bool "Flattened Device Tree support"
1398 select IRQ_DOMAIN
1399 select OF
1400 help
1401 Include support for flattened device tree machine descriptions.
1402
1403config ARCH_WANT_FLAT_DTB_INSTALL
1404 def_bool y
1405
1406config ATAGS
1407 bool "Support for the traditional ATAGS boot data passing"
1408 default y
1409 help
1410 This is the traditional way of passing data to the kernel at boot
1411 time. If you are solely relying on the flattened device tree (or
1412 the ARM_ATAG_DTB_COMPAT option) then you may unselect this option
1413 to remove ATAGS support from your kernel binary.
1414
1415config DEPRECATED_PARAM_STRUCT
1416 bool "Provide old way to pass kernel parameters"
1417 depends on ATAGS
1418 help
1419 This was deprecated in 2001 and announced to live on for 5 years.
1420 Some old boot loaders still use this way.
1421
1422# Compressed boot loader in ROM. Yes, we really want to ask about
1423# TEXT and BSS so we preserve their values in the config files.
1424config ZBOOT_ROM_TEXT
1425 hex "Compressed ROM boot loader base address"
1426 default 0x0
1427 help
1428 The physical address at which the ROM-able zImage is to be
1429 placed in the target. Platforms which normally make use of
1430 ROM-able zImage formats normally set this to a suitable
1431 value in their defconfig file.
1432
1433 If ZBOOT_ROM is not enabled, this has no effect.
1434
1435config ZBOOT_ROM_BSS
1436 hex "Compressed ROM boot loader BSS address"
1437 default 0x0
1438 help
1439 The base address of an area of read/write memory in the target
1440 for the ROM-able zImage which must be available while the
1441 decompressor is running. It must be large enough to hold the
1442 entire decompressed kernel plus an additional 128 KiB.
1443 Platforms which normally make use of ROM-able zImage formats
1444 normally set this to a suitable value in their defconfig file.
1445
1446 If ZBOOT_ROM is not enabled, this has no effect.
1447
1448config ZBOOT_ROM
1449 bool "Compressed boot loader in ROM/flash"
1450 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1451 depends on !ARM_APPENDED_DTB && !XIP_KERNEL && !AUTO_ZRELADDR
1452 help
1453 Say Y here if you intend to execute your compressed kernel image
1454 (zImage) directly from ROM or flash. If unsure, say N.
1455
1456config ARM_APPENDED_DTB
1457 bool "Use appended device tree blob to zImage (EXPERIMENTAL)"
1458 depends on OF
1459 help
1460 With this option, the boot code will look for a device tree binary
1461 (DTB) appended to zImage
1462 (e.g. cat zImage <filename>.dtb > zImage_w_dtb).
1463
1464 This is meant as a backward compatibility convenience for those
1465 systems with a bootloader that can't be upgraded to accommodate
1466 the documented boot protocol using a device tree.
1467
1468 Beware that there is very little in terms of protection against
1469 this option being confused by leftover garbage in memory that might
1470 look like a DTB header after a reboot if no actual DTB is appended
1471 to zImage. Do not leave this option active in a production kernel
1472 if you don't intend to always append a DTB. Proper passing of the
1473 location into r2 of a bootloader provided DTB is always preferable
1474 to this option.
1475
1476config ARM_ATAG_DTB_COMPAT
1477 bool "Supplement the appended DTB with traditional ATAG information"
1478 depends on ARM_APPENDED_DTB
1479 help
1480 Some old bootloaders can't be updated to a DTB capable one, yet
1481 they provide ATAGs with memory configuration, the ramdisk address,
1482 the kernel cmdline string, etc. Such information is dynamically
1483 provided by the bootloader and can't always be stored in a static
1484 DTB. To allow a device tree enabled kernel to be used with such
1485 bootloaders, this option allows zImage to extract the information
1486 from the ATAG list and store it at run time into the appended DTB.
1487
1488choice
1489 prompt "Kernel command line type"
1490 depends on ARM_ATAG_DTB_COMPAT
1491 default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1492
1493config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1494 bool "Use bootloader kernel arguments if available"
1495 help
1496 Uses the command-line options passed by the boot loader instead of
1497 the device tree bootargs property. If the boot loader doesn't provide
1498 any, the device tree bootargs property will be used.
1499
1500config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND
1501 bool "Extend with bootloader kernel arguments"
1502 help
1503 The command-line arguments provided by the boot loader will be
1504 appended to the the device tree bootargs property.
1505
1506endchoice
1507
1508config CMDLINE
1509 string "Default kernel command string"
1510 default ""
1511 help
1512 On some architectures (e.g. CATS), there is currently no way
1513 for the boot loader to pass arguments to the kernel. For these
1514 architectures, you should supply some command-line options at build
1515 time by entering them here. As a minimum, you should specify the
1516 memory size and the root device (e.g., mem=64M root=/dev/nfs).
1517
1518choice
1519 prompt "Kernel command line type"
1520 depends on CMDLINE != ""
1521 default CMDLINE_FROM_BOOTLOADER
1522
1523config CMDLINE_FROM_BOOTLOADER
1524 bool "Use bootloader kernel arguments if available"
1525 help
1526 Uses the command-line options passed by the boot loader. If
1527 the boot loader doesn't provide any, the default kernel command
1528 string provided in CMDLINE will be used.
1529
1530config CMDLINE_EXTEND
1531 bool "Extend bootloader kernel arguments"
1532 help
1533 The command-line arguments provided by the boot loader will be
1534 appended to the default kernel command string.
1535
1536config CMDLINE_FORCE
1537 bool "Always use the default kernel command string"
1538 help
1539 Always use the default kernel command string, even if the boot
1540 loader passes other arguments to the kernel.
1541 This is useful if you cannot or don't want to change the
1542 command-line options your boot loader passes to the kernel.
1543endchoice
1544
1545config XIP_KERNEL
1546 bool "Kernel Execute-In-Place from ROM"
1547 depends on !ARM_LPAE && !ARCH_MULTIPLATFORM
1548 depends on !ARM_PATCH_IDIV && !ARM_PATCH_PHYS_VIRT && !SMP_ON_UP
1549 help
1550 Execute-In-Place allows the kernel to run from non-volatile storage
1551 directly addressable by the CPU, such as NOR flash. This saves RAM
1552 space since the text section of the kernel is not loaded from flash
1553 to RAM. Read-write sections, such as the data section and stack,
1554 are still copied to RAM. The XIP kernel is not compressed since
1555 it has to run directly from flash, so it will take more space to
1556 store it. The flash address used to link the kernel object files,
1557 and for storing it, is configuration dependent. Therefore, if you
1558 say Y here, you must know the proper physical address where to
1559 store the kernel image depending on your own flash memory usage.
1560
1561 Also note that the make target becomes "make xipImage" rather than
1562 "make zImage" or "make Image". The final kernel binary to put in
1563 ROM memory will be arch/arm/boot/xipImage.
1564
1565 If unsure, say N.
1566
1567config XIP_PHYS_ADDR
1568 hex "XIP Kernel Physical Location"
1569 depends on XIP_KERNEL
1570 default "0x00080000"
1571 help
1572 This is the physical address in your flash memory the kernel will
1573 be linked for and stored to. This address is dependent on your
1574 own flash usage.
1575
1576config XIP_DEFLATED_DATA
1577 bool "Store kernel .data section compressed in ROM"
1578 depends on XIP_KERNEL
1579 select ZLIB_INFLATE
1580 help
1581 Before the kernel is actually executed, its .data section has to be
1582 copied to RAM from ROM. This option allows for storing that data
1583 in compressed form and decompressed to RAM rather than merely being
1584 copied, saving some precious ROM space. A possible drawback is a
1585 slightly longer boot delay.
1586
1587config ARCH_SUPPORTS_KEXEC
1588 def_bool (!SMP || PM_SLEEP_SMP) && MMU
1589
1590config ATAGS_PROC
1591 bool "Export atags in procfs"
1592 depends on ATAGS && KEXEC
1593 default y
1594 help
1595 Should the atags used to boot the kernel be exported in an "atags"
1596 file in procfs. Useful with kexec.
1597
1598config ARCH_SUPPORTS_CRASH_DUMP
1599 def_bool y
1600
1601config ARCH_DEFAULT_CRASH_DUMP
1602 def_bool y
1603
1604config AUTO_ZRELADDR
1605 bool "Auto calculation of the decompressed kernel image address" if !ARCH_MULTIPLATFORM
1606 default !(ARCH_FOOTBRIDGE || ARCH_RPC || ARCH_SA1100)
1607 help
1608 ZRELADDR is the physical address where the decompressed kernel
1609 image will be placed. If AUTO_ZRELADDR is selected, the address
1610 will be determined at run-time, either by masking the current IP
1611 with 0xf8000000, or, if invalid, from the DTB passed in r2.
1612 This assumes the zImage being placed in the first 128MB from
1613 start of memory.
1614
1615config EFI_STUB
1616 bool
1617
1618config EFI
1619 bool "UEFI runtime support"
1620 depends on OF && !CPU_BIG_ENDIAN && MMU && AUTO_ZRELADDR && !XIP_KERNEL
1621 select UCS2_STRING
1622 select EFI_PARAMS_FROM_FDT
1623 select EFI_STUB
1624 select EFI_GENERIC_STUB
1625 select EFI_RUNTIME_WRAPPERS
1626 help
1627 This option provides support for runtime services provided
1628 by UEFI firmware (such as non-volatile variables, realtime
1629 clock, and platform reset). A UEFI stub is also provided to
1630 allow the kernel to be booted as an EFI application. This
1631 is only useful for kernels that may run on systems that have
1632 UEFI firmware.
1633
1634config DMI
1635 bool "Enable support for SMBIOS (DMI) tables"
1636 depends on EFI
1637 default y
1638 help
1639 This enables SMBIOS/DMI feature for systems.
1640
1641 This option is only useful on systems that have UEFI firmware.
1642 However, even with this option, the resultant kernel should
1643 continue to boot on existing non-UEFI platforms.
1644
1645 NOTE: This does *NOT* enable or encourage the use of DMI quirks,
1646 i.e., the the practice of identifying the platform via DMI to
1647 decide whether certain workarounds for buggy hardware and/or
1648 firmware need to be enabled. This would require the DMI subsystem
1649 to be enabled much earlier than we do on ARM, which is non-trivial.
1650
1651endmenu
1652
1653menu "CPU Power Management"
1654
1655source "drivers/cpufreq/Kconfig"
1656
1657source "drivers/cpuidle/Kconfig"
1658
1659endmenu
1660
1661menu "Floating point emulation"
1662
1663comment "At least one emulation must be selected"
1664
1665config FPE_NWFPE
1666 bool "NWFPE math emulation"
1667 depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL
1668 help
1669 Say Y to include the NWFPE floating point emulator in the kernel.
1670 This is necessary to run most binaries. Linux does not currently
1671 support floating point hardware so you need to say Y here even if
1672 your machine has an FPA or floating point co-processor podule.
1673
1674 You may say N here if you are going to load the Acorn FPEmulator
1675 early in the bootup.
1676
1677config FPE_NWFPE_XP
1678 bool "Support extended precision"
1679 depends on FPE_NWFPE
1680 help
1681 Say Y to include 80-bit support in the kernel floating-point
1682 emulator. Otherwise, only 32 and 64-bit support is compiled in.
1683 Note that gcc does not generate 80-bit operations by default,
1684 so in most cases this option only enlarges the size of the
1685 floating point emulator without any good reason.
1686
1687 You almost surely want to say N here.
1688
1689config FPE_FASTFPE
1690 bool "FastFPE math emulation (EXPERIMENTAL)"
1691 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3
1692 help
1693 Say Y here to include the FAST floating point emulator in the kernel.
1694 This is an experimental much faster emulator which now also has full
1695 precision for the mantissa. It does not support any exceptions.
1696 It is very simple, and approximately 3-6 times faster than NWFPE.
1697
1698 It should be sufficient for most programs. It may be not suitable
1699 for scientific calculations, but you have to check this for yourself.
1700 If you do not feel you need a faster FP emulation you should better
1701 choose NWFPE.
1702
1703config VFP
1704 bool "VFP-format floating point maths"
1705 depends on CPU_V6 || CPU_V6K || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
1706 help
1707 Say Y to include VFP support code in the kernel. This is needed
1708 if your hardware includes a VFP unit.
1709
1710 Please see <file:Documentation/arch/arm/vfp/release-notes.rst> for
1711 release notes and additional status information.
1712
1713 Say N if your target does not have VFP hardware.
1714
1715config VFPv3
1716 bool
1717 depends on VFP
1718 default y if CPU_V7
1719
1720config NEON
1721 bool "Advanced SIMD (NEON) Extension support"
1722 depends on VFPv3 && CPU_V7
1723 help
1724 Say Y to include support code for NEON, the ARMv7 Advanced SIMD
1725 Extension.
1726
1727config KERNEL_MODE_NEON
1728 bool "Support for NEON in kernel mode"
1729 depends on NEON && AEABI
1730 help
1731 Say Y to include support for NEON in kernel mode.
1732
1733endmenu
1734
1735menu "Power management options"
1736
1737source "kernel/power/Kconfig"
1738
1739config ARCH_SUSPEND_POSSIBLE
1740 depends on CPU_ARM920T || CPU_ARM926T || CPU_FEROCEON || CPU_SA1100 || \
1741 CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7M || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK
1742 def_bool y
1743
1744config ARM_CPU_SUSPEND
1745 def_bool PM_SLEEP || BL_SWITCHER || ARM_PSCI_FW
1746 depends on ARCH_SUSPEND_POSSIBLE
1747
1748config ARCH_HIBERNATION_POSSIBLE
1749 bool
1750 depends on MMU
1751 default y if ARCH_SUSPEND_POSSIBLE
1752
1753endmenu
1754
1755source "arch/arm/Kconfig.assembler"
1config ARM
2 bool
3 default y
4 select ARCH_HAVE_CUSTOM_GPIO_H
5 select HAVE_AOUT
6 select HAVE_DMA_API_DEBUG
7 select HAVE_IDE if PCI || ISA || PCMCIA
8 select HAVE_DMA_ATTRS
9 select HAVE_DMA_CONTIGUOUS if (CPU_V6 || CPU_V6K || CPU_V7)
10 select HAVE_MEMBLOCK
11 select RTC_LIB
12 select SYS_SUPPORTS_APM_EMULATION
13 select GENERIC_ATOMIC64 if (CPU_V6 || !CPU_32v6K || !AEABI)
14 select HAVE_OPROFILE if (HAVE_PERF_EVENTS)
15 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
16 select HAVE_ARCH_KGDB
17 select HAVE_ARCH_TRACEHOOK
18 select HAVE_KPROBES if !XIP_KERNEL
19 select HAVE_KRETPROBES if (HAVE_KPROBES)
20 select HAVE_FUNCTION_TRACER if (!XIP_KERNEL)
21 select HAVE_FTRACE_MCOUNT_RECORD if (!XIP_KERNEL)
22 select HAVE_DYNAMIC_FTRACE if (!XIP_KERNEL)
23 select HAVE_FUNCTION_GRAPH_TRACER if (!THUMB2_KERNEL)
24 select ARCH_BINFMT_ELF_RANDOMIZE_PIE
25 select HAVE_GENERIC_DMA_COHERENT
26 select HAVE_KERNEL_GZIP
27 select HAVE_KERNEL_LZO
28 select HAVE_KERNEL_LZMA
29 select HAVE_KERNEL_XZ
30 select HAVE_IRQ_WORK
31 select HAVE_PERF_EVENTS
32 select PERF_USE_VMALLOC
33 select HAVE_REGS_AND_STACK_ACCESS_API
34 select HAVE_HW_BREAKPOINT if (PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7))
35 select HAVE_C_RECORDMCOUNT
36 select HAVE_GENERIC_HARDIRQS
37 select HARDIRQS_SW_RESEND
38 select GENERIC_IRQ_PROBE
39 select GENERIC_IRQ_SHOW
40 select GENERIC_IRQ_PROBE
41 select HARDIRQS_SW_RESEND
42 select CPU_PM if (SUSPEND || CPU_IDLE)
43 select GENERIC_PCI_IOMAP
44 select HAVE_BPF_JIT
45 select GENERIC_SMP_IDLE_THREAD
46 select KTIME_SCALAR
47 select GENERIC_CLOCKEVENTS_BROADCAST if SMP
48 help
49 The ARM series is a line of low-power-consumption RISC chip designs
50 licensed by ARM Ltd and targeted at embedded applications and
51 handhelds such as the Compaq IPAQ. ARM-based PCs are no longer
52 manufactured, but legacy ARM-based PC hardware remains popular in
53 Europe. There is an ARM Linux project with a web page at
54 <http://www.arm.linux.org.uk/>.
55
56config ARM_HAS_SG_CHAIN
57 bool
58
59config NEED_SG_DMA_LENGTH
60 bool
61
62config ARM_DMA_USE_IOMMU
63 select NEED_SG_DMA_LENGTH
64 select ARM_HAS_SG_CHAIN
65 bool
66
67config HAVE_PWM
68 bool
69
70config MIGHT_HAVE_PCI
71 bool
72
73config SYS_SUPPORTS_APM_EMULATION
74 bool
75
76config GENERIC_GPIO
77 bool
78
79config HAVE_TCM
80 bool
81 select GENERIC_ALLOCATOR
82
83config HAVE_PROC_CPU
84 bool
85
86config NO_IOPORT
87 bool
88
89config EISA
90 bool
91 ---help---
92 The Extended Industry Standard Architecture (EISA) bus was
93 developed as an open alternative to the IBM MicroChannel bus.
94
95 The EISA bus provided some of the features of the IBM MicroChannel
96 bus while maintaining backward compatibility with cards made for
97 the older ISA bus. The EISA bus saw limited use between 1988 and
98 1995 when it was made obsolete by the PCI bus.
99
100 Say Y here if you are building a kernel for an EISA-based machine.
101
102 Otherwise, say N.
103
104config SBUS
105 bool
106
107config STACKTRACE_SUPPORT
108 bool
109 default y
110
111config HAVE_LATENCYTOP_SUPPORT
112 bool
113 depends on !SMP
114 default y
115
116config LOCKDEP_SUPPORT
117 bool
118 default y
119
120config TRACE_IRQFLAGS_SUPPORT
121 bool
122 default y
123
124config GENERIC_LOCKBREAK
125 bool
126 default y
127 depends on SMP && PREEMPT
128
129config RWSEM_GENERIC_SPINLOCK
130 bool
131 default y
132
133config RWSEM_XCHGADD_ALGORITHM
134 bool
135
136config ARCH_HAS_ILOG2_U32
137 bool
138
139config ARCH_HAS_ILOG2_U64
140 bool
141
142config ARCH_HAS_CPUFREQ
143 bool
144 help
145 Internal node to signify that the ARCH has CPUFREQ support
146 and that the relevant menu configurations are displayed for
147 it.
148
149config GENERIC_HWEIGHT
150 bool
151 default y
152
153config GENERIC_CALIBRATE_DELAY
154 bool
155 default y
156
157config ARCH_MAY_HAVE_PC_FDC
158 bool
159
160config ZONE_DMA
161 bool
162
163config NEED_DMA_MAP_STATE
164 def_bool y
165
166config ARCH_HAS_DMA_SET_COHERENT_MASK
167 bool
168
169config GENERIC_ISA_DMA
170 bool
171
172config FIQ
173 bool
174
175config NEED_RET_TO_USER
176 bool
177
178config ARCH_MTD_XIP
179 bool
180
181config VECTORS_BASE
182 hex
183 default 0xffff0000 if MMU || CPU_HIGH_VECTOR
184 default DRAM_BASE if REMAP_VECTORS_TO_RAM
185 default 0x00000000
186 help
187 The base address of exception vectors.
188
189config ARM_PATCH_PHYS_VIRT
190 bool "Patch physical to virtual translations at runtime" if EMBEDDED
191 default y
192 depends on !XIP_KERNEL && MMU
193 depends on !ARCH_REALVIEW || !SPARSEMEM
194 help
195 Patch phys-to-virt and virt-to-phys translation functions at
196 boot and module load time according to the position of the
197 kernel in system memory.
198
199 This can only be used with non-XIP MMU kernels where the base
200 of physical memory is at a 16MB boundary.
201
202 Only disable this option if you know that you do not require
203 this feature (eg, building a kernel for a single machine) and
204 you need to shrink the kernel to the minimal size.
205
206config NEED_MACH_IO_H
207 bool
208 help
209 Select this when mach/io.h is required to provide special
210 definitions for this platform. The need for mach/io.h should
211 be avoided when possible.
212
213config NEED_MACH_MEMORY_H
214 bool
215 help
216 Select this when mach/memory.h is required to provide special
217 definitions for this platform. The need for mach/memory.h should
218 be avoided when possible.
219
220config PHYS_OFFSET
221 hex "Physical address of main memory" if MMU
222 depends on !ARM_PATCH_PHYS_VIRT && !NEED_MACH_MEMORY_H
223 default DRAM_BASE if !MMU
224 help
225 Please provide the physical address corresponding to the
226 location of main memory in your system.
227
228config GENERIC_BUG
229 def_bool y
230 depends on BUG
231
232source "init/Kconfig"
233
234source "kernel/Kconfig.freezer"
235
236menu "System Type"
237
238config MMU
239 bool "MMU-based Paged Memory Management Support"
240 default y
241 help
242 Select if you want MMU-based virtualised addressing space
243 support by paged memory management. If unsure, say 'Y'.
244
245#
246# The "ARM system type" choice list is ordered alphabetically by option
247# text. Please add new entries in the option alphabetic order.
248#
249choice
250 prompt "ARM system type"
251 default ARCH_VERSATILE
252
253config ARCH_INTEGRATOR
254 bool "ARM Ltd. Integrator family"
255 select ARM_AMBA
256 select ARCH_HAS_CPUFREQ
257 select CLKDEV_LOOKUP
258 select HAVE_MACH_CLKDEV
259 select HAVE_TCM
260 select ICST
261 select GENERIC_CLOCKEVENTS
262 select PLAT_VERSATILE
263 select PLAT_VERSATILE_FPGA_IRQ
264 select NEED_MACH_IO_H
265 select NEED_MACH_MEMORY_H
266 select SPARSE_IRQ
267 select MULTI_IRQ_HANDLER
268 help
269 Support for ARM's Integrator platform.
270
271config ARCH_REALVIEW
272 bool "ARM Ltd. RealView family"
273 select ARM_AMBA
274 select CLKDEV_LOOKUP
275 select HAVE_MACH_CLKDEV
276 select ICST
277 select GENERIC_CLOCKEVENTS
278 select ARCH_WANT_OPTIONAL_GPIOLIB
279 select PLAT_VERSATILE
280 select PLAT_VERSATILE_CLCD
281 select ARM_TIMER_SP804
282 select GPIO_PL061 if GPIOLIB
283 select NEED_MACH_MEMORY_H
284 help
285 This enables support for ARM Ltd RealView boards.
286
287config ARCH_VERSATILE
288 bool "ARM Ltd. Versatile family"
289 select ARM_AMBA
290 select ARM_VIC
291 select CLKDEV_LOOKUP
292 select HAVE_MACH_CLKDEV
293 select ICST
294 select GENERIC_CLOCKEVENTS
295 select ARCH_WANT_OPTIONAL_GPIOLIB
296 select NEED_MACH_IO_H if PCI
297 select PLAT_VERSATILE
298 select PLAT_VERSATILE_CLCD
299 select PLAT_VERSATILE_FPGA_IRQ
300 select ARM_TIMER_SP804
301 help
302 This enables support for ARM Ltd Versatile board.
303
304config ARCH_VEXPRESS
305 bool "ARM Ltd. Versatile Express family"
306 select ARCH_WANT_OPTIONAL_GPIOLIB
307 select ARM_AMBA
308 select ARM_TIMER_SP804
309 select CLKDEV_LOOKUP
310 select HAVE_MACH_CLKDEV
311 select GENERIC_CLOCKEVENTS
312 select HAVE_CLK
313 select HAVE_PATA_PLATFORM
314 select ICST
315 select NO_IOPORT
316 select PLAT_VERSATILE
317 select PLAT_VERSATILE_CLCD
318 help
319 This enables support for the ARM Ltd Versatile Express boards.
320
321config ARCH_AT91
322 bool "Atmel AT91"
323 select ARCH_REQUIRE_GPIOLIB
324 select HAVE_CLK
325 select CLKDEV_LOOKUP
326 select IRQ_DOMAIN
327 select NEED_MACH_IO_H if PCCARD
328 help
329 This enables support for systems based on Atmel
330 AT91RM9200 and AT91SAM9* processors.
331
332config ARCH_BCMRING
333 bool "Broadcom BCMRING"
334 depends on MMU
335 select CPU_V6
336 select ARM_AMBA
337 select ARM_TIMER_SP804
338 select CLKDEV_LOOKUP
339 select GENERIC_CLOCKEVENTS
340 select ARCH_WANT_OPTIONAL_GPIOLIB
341 help
342 Support for Broadcom's BCMRing platform.
343
344config ARCH_HIGHBANK
345 bool "Calxeda Highbank-based"
346 select ARCH_WANT_OPTIONAL_GPIOLIB
347 select ARM_AMBA
348 select ARM_GIC
349 select ARM_TIMER_SP804
350 select CACHE_L2X0
351 select CLKDEV_LOOKUP
352 select CPU_V7
353 select GENERIC_CLOCKEVENTS
354 select HAVE_ARM_SCU
355 select HAVE_SMP
356 select SPARSE_IRQ
357 select USE_OF
358 help
359 Support for the Calxeda Highbank SoC based boards.
360
361config ARCH_CLPS711X
362 bool "Cirrus Logic CLPS711x/EP721x/EP731x-based"
363 select CPU_ARM720T
364 select ARCH_USES_GETTIMEOFFSET
365 select NEED_MACH_MEMORY_H
366 help
367 Support for Cirrus Logic 711x/721x/731x based boards.
368
369config ARCH_CNS3XXX
370 bool "Cavium Networks CNS3XXX family"
371 select CPU_V6K
372 select GENERIC_CLOCKEVENTS
373 select ARM_GIC
374 select MIGHT_HAVE_CACHE_L2X0
375 select MIGHT_HAVE_PCI
376 select PCI_DOMAINS if PCI
377 help
378 Support for Cavium Networks CNS3XXX platform.
379
380config ARCH_GEMINI
381 bool "Cortina Systems Gemini"
382 select CPU_FA526
383 select ARCH_REQUIRE_GPIOLIB
384 select ARCH_USES_GETTIMEOFFSET
385 help
386 Support for the Cortina Systems Gemini family SoCs
387
388config ARCH_PRIMA2
389 bool "CSR SiRFSoC PRIMA2 ARM Cortex A9 Platform"
390 select CPU_V7
391 select NO_IOPORT
392 select GENERIC_CLOCKEVENTS
393 select CLKDEV_LOOKUP
394 select GENERIC_IRQ_CHIP
395 select MIGHT_HAVE_CACHE_L2X0
396 select PINCTRL
397 select PINCTRL_SIRF
398 select USE_OF
399 select ZONE_DMA
400 help
401 Support for CSR SiRFSoC ARM Cortex A9 Platform
402
403config ARCH_EBSA110
404 bool "EBSA-110"
405 select CPU_SA110
406 select ISA
407 select NO_IOPORT
408 select ARCH_USES_GETTIMEOFFSET
409 select NEED_MACH_IO_H
410 select NEED_MACH_MEMORY_H
411 help
412 This is an evaluation board for the StrongARM processor available
413 from Digital. It has limited hardware on-board, including an
414 Ethernet interface, two PCMCIA sockets, two serial ports and a
415 parallel port.
416
417config ARCH_EP93XX
418 bool "EP93xx-based"
419 select CPU_ARM920T
420 select ARM_AMBA
421 select ARM_VIC
422 select CLKDEV_LOOKUP
423 select ARCH_REQUIRE_GPIOLIB
424 select ARCH_HAS_HOLES_MEMORYMODEL
425 select ARCH_USES_GETTIMEOFFSET
426 select NEED_MACH_MEMORY_H
427 help
428 This enables support for the Cirrus EP93xx series of CPUs.
429
430config ARCH_FOOTBRIDGE
431 bool "FootBridge"
432 select CPU_SA110
433 select FOOTBRIDGE
434 select GENERIC_CLOCKEVENTS
435 select HAVE_IDE
436 select NEED_MACH_IO_H
437 select NEED_MACH_MEMORY_H
438 help
439 Support for systems based on the DC21285 companion chip
440 ("FootBridge"), such as the Simtec CATS and the Rebel NetWinder.
441
442config ARCH_MXC
443 bool "Freescale MXC/iMX-based"
444 select GENERIC_CLOCKEVENTS
445 select ARCH_REQUIRE_GPIOLIB
446 select CLKDEV_LOOKUP
447 select CLKSRC_MMIO
448 select GENERIC_IRQ_CHIP
449 select MULTI_IRQ_HANDLER
450 help
451 Support for Freescale MXC/iMX-based family of processors
452
453config ARCH_MXS
454 bool "Freescale MXS-based"
455 select GENERIC_CLOCKEVENTS
456 select ARCH_REQUIRE_GPIOLIB
457 select CLKDEV_LOOKUP
458 select CLKSRC_MMIO
459 select COMMON_CLK
460 select HAVE_CLK_PREPARE
461 select PINCTRL
462 select USE_OF
463 help
464 Support for Freescale MXS-based family of processors
465
466config ARCH_NETX
467 bool "Hilscher NetX based"
468 select CLKSRC_MMIO
469 select CPU_ARM926T
470 select ARM_VIC
471 select GENERIC_CLOCKEVENTS
472 help
473 This enables support for systems based on the Hilscher NetX Soc
474
475config ARCH_H720X
476 bool "Hynix HMS720x-based"
477 select CPU_ARM720T
478 select ISA_DMA_API
479 select ARCH_USES_GETTIMEOFFSET
480 help
481 This enables support for systems based on the Hynix HMS720x
482
483config ARCH_IOP13XX
484 bool "IOP13xx-based"
485 depends on MMU
486 select CPU_XSC3
487 select PLAT_IOP
488 select PCI
489 select ARCH_SUPPORTS_MSI
490 select VMSPLIT_1G
491 select NEED_MACH_IO_H
492 select NEED_MACH_MEMORY_H
493 select NEED_RET_TO_USER
494 help
495 Support for Intel's IOP13XX (XScale) family of processors.
496
497config ARCH_IOP32X
498 bool "IOP32x-based"
499 depends on MMU
500 select CPU_XSCALE
501 select NEED_MACH_IO_H
502 select NEED_RET_TO_USER
503 select PLAT_IOP
504 select PCI
505 select ARCH_REQUIRE_GPIOLIB
506 help
507 Support for Intel's 80219 and IOP32X (XScale) family of
508 processors.
509
510config ARCH_IOP33X
511 bool "IOP33x-based"
512 depends on MMU
513 select CPU_XSCALE
514 select NEED_MACH_IO_H
515 select NEED_RET_TO_USER
516 select PLAT_IOP
517 select PCI
518 select ARCH_REQUIRE_GPIOLIB
519 help
520 Support for Intel's IOP33X (XScale) family of processors.
521
522config ARCH_IXP4XX
523 bool "IXP4xx-based"
524 depends on MMU
525 select ARCH_HAS_DMA_SET_COHERENT_MASK
526 select CLKSRC_MMIO
527 select CPU_XSCALE
528 select ARCH_REQUIRE_GPIOLIB
529 select GENERIC_CLOCKEVENTS
530 select MIGHT_HAVE_PCI
531 select NEED_MACH_IO_H
532 select DMABOUNCE if PCI
533 help
534 Support for Intel's IXP4XX (XScale) family of processors.
535
536config ARCH_DOVE
537 bool "Marvell Dove"
538 select CPU_V7
539 select PCI
540 select ARCH_REQUIRE_GPIOLIB
541 select GENERIC_CLOCKEVENTS
542 select NEED_MACH_IO_H
543 select PLAT_ORION
544 help
545 Support for the Marvell Dove SoC 88AP510
546
547config ARCH_KIRKWOOD
548 bool "Marvell Kirkwood"
549 select CPU_FEROCEON
550 select PCI
551 select ARCH_REQUIRE_GPIOLIB
552 select GENERIC_CLOCKEVENTS
553 select NEED_MACH_IO_H
554 select PLAT_ORION
555 help
556 Support for the following Marvell Kirkwood series SoCs:
557 88F6180, 88F6192 and 88F6281.
558
559config ARCH_LPC32XX
560 bool "NXP LPC32XX"
561 select CLKSRC_MMIO
562 select CPU_ARM926T
563 select ARCH_REQUIRE_GPIOLIB
564 select HAVE_IDE
565 select ARM_AMBA
566 select USB_ARCH_HAS_OHCI
567 select CLKDEV_LOOKUP
568 select GENERIC_CLOCKEVENTS
569 select USE_OF
570 help
571 Support for the NXP LPC32XX family of processors
572
573config ARCH_MV78XX0
574 bool "Marvell MV78xx0"
575 select CPU_FEROCEON
576 select PCI
577 select ARCH_REQUIRE_GPIOLIB
578 select GENERIC_CLOCKEVENTS
579 select NEED_MACH_IO_H
580 select PLAT_ORION
581 help
582 Support for the following Marvell MV78xx0 series SoCs:
583 MV781x0, MV782x0.
584
585config ARCH_ORION5X
586 bool "Marvell Orion"
587 depends on MMU
588 select CPU_FEROCEON
589 select PCI
590 select ARCH_REQUIRE_GPIOLIB
591 select GENERIC_CLOCKEVENTS
592 select NEED_MACH_IO_H
593 select PLAT_ORION
594 help
595 Support for the following Marvell Orion 5x series SoCs:
596 Orion-1 (5181), Orion-VoIP (5181L), Orion-NAS (5182),
597 Orion-2 (5281), Orion-1-90 (6183).
598
599config ARCH_MMP
600 bool "Marvell PXA168/910/MMP2"
601 depends on MMU
602 select ARCH_REQUIRE_GPIOLIB
603 select CLKDEV_LOOKUP
604 select GENERIC_CLOCKEVENTS
605 select GPIO_PXA
606 select IRQ_DOMAIN
607 select PLAT_PXA
608 select SPARSE_IRQ
609 select GENERIC_ALLOCATOR
610 help
611 Support for Marvell's PXA168/PXA910(MMP) and MMP2 processor line.
612
613config ARCH_KS8695
614 bool "Micrel/Kendin KS8695"
615 select CPU_ARM922T
616 select ARCH_REQUIRE_GPIOLIB
617 select ARCH_USES_GETTIMEOFFSET
618 select NEED_MACH_MEMORY_H
619 help
620 Support for Micrel/Kendin KS8695 "Centaur" (ARM922T) based
621 System-on-Chip devices.
622
623config ARCH_W90X900
624 bool "Nuvoton W90X900 CPU"
625 select CPU_ARM926T
626 select ARCH_REQUIRE_GPIOLIB
627 select CLKDEV_LOOKUP
628 select CLKSRC_MMIO
629 select GENERIC_CLOCKEVENTS
630 help
631 Support for Nuvoton (Winbond logic dept.) ARM9 processor,
632 At present, the w90x900 has been renamed nuc900, regarding
633 the ARM series product line, you can login the following
634 link address to know more.
635
636 <http://www.nuvoton.com/hq/enu/ProductAndSales/ProductLines/
637 ConsumerElectronicsIC/ARMMicrocontroller/ARMMicrocontroller>
638
639config ARCH_TEGRA
640 bool "NVIDIA Tegra"
641 select CLKDEV_LOOKUP
642 select CLKSRC_MMIO
643 select GENERIC_CLOCKEVENTS
644 select GENERIC_GPIO
645 select HAVE_CLK
646 select HAVE_SMP
647 select MIGHT_HAVE_CACHE_L2X0
648 select NEED_MACH_IO_H if PCI
649 select ARCH_HAS_CPUFREQ
650 help
651 This enables support for NVIDIA Tegra based systems (Tegra APX,
652 Tegra 6xx and Tegra 2 series).
653
654config ARCH_PICOXCELL
655 bool "Picochip picoXcell"
656 select ARCH_REQUIRE_GPIOLIB
657 select ARM_PATCH_PHYS_VIRT
658 select ARM_VIC
659 select CPU_V6K
660 select DW_APB_TIMER
661 select GENERIC_CLOCKEVENTS
662 select GENERIC_GPIO
663 select HAVE_TCM
664 select NO_IOPORT
665 select SPARSE_IRQ
666 select USE_OF
667 help
668 This enables support for systems based on the Picochip picoXcell
669 family of Femtocell devices. The picoxcell support requires device tree
670 for all boards.
671
672config ARCH_PNX4008
673 bool "Philips Nexperia PNX4008 Mobile"
674 select CPU_ARM926T
675 select CLKDEV_LOOKUP
676 select ARCH_USES_GETTIMEOFFSET
677 help
678 This enables support for Philips PNX4008 mobile platform.
679
680config ARCH_PXA
681 bool "PXA2xx/PXA3xx-based"
682 depends on MMU
683 select ARCH_MTD_XIP
684 select ARCH_HAS_CPUFREQ
685 select CLKDEV_LOOKUP
686 select CLKSRC_MMIO
687 select ARCH_REQUIRE_GPIOLIB
688 select GENERIC_CLOCKEVENTS
689 select GPIO_PXA
690 select PLAT_PXA
691 select SPARSE_IRQ
692 select AUTO_ZRELADDR
693 select MULTI_IRQ_HANDLER
694 select ARM_CPU_SUSPEND if PM
695 select HAVE_IDE
696 help
697 Support for Intel/Marvell's PXA2xx/PXA3xx processor line.
698
699config ARCH_MSM
700 bool "Qualcomm MSM"
701 select HAVE_CLK
702 select GENERIC_CLOCKEVENTS
703 select ARCH_REQUIRE_GPIOLIB
704 select CLKDEV_LOOKUP
705 help
706 Support for Qualcomm MSM/QSD based systems. This runs on the
707 apps processor of the MSM/QSD and depends on a shared memory
708 interface to the modem processor which runs the baseband
709 stack and controls some vital subsystems
710 (clock and power control, etc).
711
712config ARCH_SHMOBILE
713 bool "Renesas SH-Mobile / R-Mobile"
714 select HAVE_CLK
715 select CLKDEV_LOOKUP
716 select HAVE_MACH_CLKDEV
717 select HAVE_SMP
718 select GENERIC_CLOCKEVENTS
719 select MIGHT_HAVE_CACHE_L2X0
720 select NO_IOPORT
721 select SPARSE_IRQ
722 select MULTI_IRQ_HANDLER
723 select PM_GENERIC_DOMAINS if PM
724 select NEED_MACH_MEMORY_H
725 help
726 Support for Renesas's SH-Mobile and R-Mobile ARM platforms.
727
728config ARCH_RPC
729 bool "RiscPC"
730 select ARCH_ACORN
731 select FIQ
732 select ARCH_MAY_HAVE_PC_FDC
733 select HAVE_PATA_PLATFORM
734 select ISA_DMA_API
735 select NO_IOPORT
736 select ARCH_SPARSEMEM_ENABLE
737 select ARCH_USES_GETTIMEOFFSET
738 select HAVE_IDE
739 select NEED_MACH_IO_H
740 select NEED_MACH_MEMORY_H
741 help
742 On the Acorn Risc-PC, Linux can support the internal IDE disk and
743 CD-ROM interface, serial and parallel port, and the floppy drive.
744
745config ARCH_SA1100
746 bool "SA1100-based"
747 select CLKSRC_MMIO
748 select CPU_SA1100
749 select ISA
750 select ARCH_SPARSEMEM_ENABLE
751 select ARCH_MTD_XIP
752 select ARCH_HAS_CPUFREQ
753 select CPU_FREQ
754 select GENERIC_CLOCKEVENTS
755 select CLKDEV_LOOKUP
756 select ARCH_REQUIRE_GPIOLIB
757 select HAVE_IDE
758 select NEED_MACH_MEMORY_H
759 select SPARSE_IRQ
760 help
761 Support for StrongARM 11x0 based boards.
762
763config ARCH_S3C24XX
764 bool "Samsung S3C24XX SoCs"
765 select GENERIC_GPIO
766 select ARCH_HAS_CPUFREQ
767 select HAVE_CLK
768 select CLKDEV_LOOKUP
769 select ARCH_USES_GETTIMEOFFSET
770 select HAVE_S3C2410_I2C if I2C
771 select HAVE_S3C_RTC if RTC_CLASS
772 select HAVE_S3C2410_WATCHDOG if WATCHDOG
773 select NEED_MACH_IO_H
774 help
775 Samsung S3C2410, S3C2412, S3C2413, S3C2416, S3C2440, S3C2442, S3C2443
776 and S3C2450 SoCs based systems, such as the Simtec Electronics BAST
777 (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or the
778 Samsung SMDK2410 development board (and derivatives).
779
780config ARCH_S3C64XX
781 bool "Samsung S3C64XX"
782 select PLAT_SAMSUNG
783 select CPU_V6
784 select ARM_VIC
785 select HAVE_CLK
786 select HAVE_TCM
787 select CLKDEV_LOOKUP
788 select NO_IOPORT
789 select ARCH_USES_GETTIMEOFFSET
790 select ARCH_HAS_CPUFREQ
791 select ARCH_REQUIRE_GPIOLIB
792 select SAMSUNG_CLKSRC
793 select SAMSUNG_IRQ_VIC_TIMER
794 select S3C_GPIO_TRACK
795 select S3C_DEV_NAND
796 select USB_ARCH_HAS_OHCI
797 select SAMSUNG_GPIOLIB_4BIT
798 select HAVE_S3C2410_I2C if I2C
799 select HAVE_S3C2410_WATCHDOG if WATCHDOG
800 help
801 Samsung S3C64XX series based systems
802
803config ARCH_S5P64X0
804 bool "Samsung S5P6440 S5P6450"
805 select CPU_V6
806 select GENERIC_GPIO
807 select HAVE_CLK
808 select CLKDEV_LOOKUP
809 select CLKSRC_MMIO
810 select HAVE_S3C2410_WATCHDOG if WATCHDOG
811 select GENERIC_CLOCKEVENTS
812 select HAVE_S3C2410_I2C if I2C
813 select HAVE_S3C_RTC if RTC_CLASS
814 help
815 Samsung S5P64X0 CPU based systems, such as the Samsung SMDK6440,
816 SMDK6450.
817
818config ARCH_S5PC100
819 bool "Samsung S5PC100"
820 select GENERIC_GPIO
821 select HAVE_CLK
822 select CLKDEV_LOOKUP
823 select CPU_V7
824 select ARCH_USES_GETTIMEOFFSET
825 select HAVE_S3C2410_I2C if I2C
826 select HAVE_S3C_RTC if RTC_CLASS
827 select HAVE_S3C2410_WATCHDOG if WATCHDOG
828 help
829 Samsung S5PC100 series based systems
830
831config ARCH_S5PV210
832 bool "Samsung S5PV210/S5PC110"
833 select CPU_V7
834 select ARCH_SPARSEMEM_ENABLE
835 select ARCH_HAS_HOLES_MEMORYMODEL
836 select GENERIC_GPIO
837 select HAVE_CLK
838 select CLKDEV_LOOKUP
839 select CLKSRC_MMIO
840 select ARCH_HAS_CPUFREQ
841 select GENERIC_CLOCKEVENTS
842 select HAVE_S3C2410_I2C if I2C
843 select HAVE_S3C_RTC if RTC_CLASS
844 select HAVE_S3C2410_WATCHDOG if WATCHDOG
845 select NEED_MACH_MEMORY_H
846 help
847 Samsung S5PV210/S5PC110 series based systems
848
849config ARCH_EXYNOS
850 bool "SAMSUNG EXYNOS"
851 select CPU_V7
852 select ARCH_SPARSEMEM_ENABLE
853 select ARCH_HAS_HOLES_MEMORYMODEL
854 select GENERIC_GPIO
855 select HAVE_CLK
856 select CLKDEV_LOOKUP
857 select ARCH_HAS_CPUFREQ
858 select GENERIC_CLOCKEVENTS
859 select HAVE_S3C_RTC if RTC_CLASS
860 select HAVE_S3C2410_I2C if I2C
861 select HAVE_S3C2410_WATCHDOG if WATCHDOG
862 select NEED_MACH_MEMORY_H
863 help
864 Support for SAMSUNG's EXYNOS SoCs (EXYNOS4/5)
865
866config ARCH_SHARK
867 bool "Shark"
868 select CPU_SA110
869 select ISA
870 select ISA_DMA
871 select ZONE_DMA
872 select PCI
873 select ARCH_USES_GETTIMEOFFSET
874 select NEED_MACH_MEMORY_H
875 select NEED_MACH_IO_H
876 help
877 Support for the StrongARM based Digital DNARD machine, also known
878 as "Shark" (<http://www.shark-linux.de/shark.html>).
879
880config ARCH_U300
881 bool "ST-Ericsson U300 Series"
882 depends on MMU
883 select CLKSRC_MMIO
884 select CPU_ARM926T
885 select HAVE_TCM
886 select ARM_AMBA
887 select ARM_PATCH_PHYS_VIRT
888 select ARM_VIC
889 select GENERIC_CLOCKEVENTS
890 select CLKDEV_LOOKUP
891 select HAVE_MACH_CLKDEV
892 select GENERIC_GPIO
893 select ARCH_REQUIRE_GPIOLIB
894 help
895 Support for ST-Ericsson U300 series mobile platforms.
896
897config ARCH_U8500
898 bool "ST-Ericsson U8500 Series"
899 depends on MMU
900 select CPU_V7
901 select ARM_AMBA
902 select GENERIC_CLOCKEVENTS
903 select CLKDEV_LOOKUP
904 select ARCH_REQUIRE_GPIOLIB
905 select ARCH_HAS_CPUFREQ
906 select HAVE_SMP
907 select MIGHT_HAVE_CACHE_L2X0
908 help
909 Support for ST-Ericsson's Ux500 architecture
910
911config ARCH_NOMADIK
912 bool "STMicroelectronics Nomadik"
913 select ARM_AMBA
914 select ARM_VIC
915 select CPU_ARM926T
916 select CLKDEV_LOOKUP
917 select GENERIC_CLOCKEVENTS
918 select PINCTRL
919 select MIGHT_HAVE_CACHE_L2X0
920 select ARCH_REQUIRE_GPIOLIB
921 help
922 Support for the Nomadik platform by ST-Ericsson
923
924config ARCH_DAVINCI
925 bool "TI DaVinci"
926 select GENERIC_CLOCKEVENTS
927 select ARCH_REQUIRE_GPIOLIB
928 select ZONE_DMA
929 select HAVE_IDE
930 select CLKDEV_LOOKUP
931 select GENERIC_ALLOCATOR
932 select GENERIC_IRQ_CHIP
933 select ARCH_HAS_HOLES_MEMORYMODEL
934 help
935 Support for TI's DaVinci platform.
936
937config ARCH_OMAP
938 bool "TI OMAP"
939 select HAVE_CLK
940 select ARCH_REQUIRE_GPIOLIB
941 select ARCH_HAS_CPUFREQ
942 select CLKSRC_MMIO
943 select GENERIC_CLOCKEVENTS
944 select ARCH_HAS_HOLES_MEMORYMODEL
945 help
946 Support for TI's OMAP platform (OMAP1/2/3/4).
947
948config PLAT_SPEAR
949 bool "ST SPEAr"
950 select ARM_AMBA
951 select ARCH_REQUIRE_GPIOLIB
952 select CLKDEV_LOOKUP
953 select COMMON_CLK
954 select CLKSRC_MMIO
955 select GENERIC_CLOCKEVENTS
956 select HAVE_CLK
957 help
958 Support for ST's SPEAr platform (SPEAr3xx, SPEAr6xx and SPEAr13xx).
959
960config ARCH_VT8500
961 bool "VIA/WonderMedia 85xx"
962 select CPU_ARM926T
963 select GENERIC_GPIO
964 select ARCH_HAS_CPUFREQ
965 select GENERIC_CLOCKEVENTS
966 select ARCH_REQUIRE_GPIOLIB
967 select HAVE_PWM
968 help
969 Support for VIA/WonderMedia VT8500/WM85xx System-on-Chip.
970
971config ARCH_ZYNQ
972 bool "Xilinx Zynq ARM Cortex A9 Platform"
973 select CPU_V7
974 select GENERIC_CLOCKEVENTS
975 select CLKDEV_LOOKUP
976 select ARM_GIC
977 select ARM_AMBA
978 select ICST
979 select MIGHT_HAVE_CACHE_L2X0
980 select USE_OF
981 help
982 Support for Xilinx Zynq ARM Cortex A9 Platform
983endchoice
984
985#
986# This is sorted alphabetically by mach-* pathname. However, plat-*
987# Kconfigs may be included either alphabetically (according to the
988# plat- suffix) or along side the corresponding mach-* source.
989#
990source "arch/arm/mach-at91/Kconfig"
991
992source "arch/arm/mach-bcmring/Kconfig"
993
994source "arch/arm/mach-clps711x/Kconfig"
995
996source "arch/arm/mach-cns3xxx/Kconfig"
997
998source "arch/arm/mach-davinci/Kconfig"
999
1000source "arch/arm/mach-dove/Kconfig"
1001
1002source "arch/arm/mach-ep93xx/Kconfig"
1003
1004source "arch/arm/mach-footbridge/Kconfig"
1005
1006source "arch/arm/mach-gemini/Kconfig"
1007
1008source "arch/arm/mach-h720x/Kconfig"
1009
1010source "arch/arm/mach-integrator/Kconfig"
1011
1012source "arch/arm/mach-iop32x/Kconfig"
1013
1014source "arch/arm/mach-iop33x/Kconfig"
1015
1016source "arch/arm/mach-iop13xx/Kconfig"
1017
1018source "arch/arm/mach-ixp4xx/Kconfig"
1019
1020source "arch/arm/mach-kirkwood/Kconfig"
1021
1022source "arch/arm/mach-ks8695/Kconfig"
1023
1024source "arch/arm/mach-lpc32xx/Kconfig"
1025
1026source "arch/arm/mach-msm/Kconfig"
1027
1028source "arch/arm/mach-mv78xx0/Kconfig"
1029
1030source "arch/arm/plat-mxc/Kconfig"
1031
1032source "arch/arm/mach-mxs/Kconfig"
1033
1034source "arch/arm/mach-netx/Kconfig"
1035
1036source "arch/arm/mach-nomadik/Kconfig"
1037source "arch/arm/plat-nomadik/Kconfig"
1038
1039source "arch/arm/plat-omap/Kconfig"
1040
1041source "arch/arm/mach-omap1/Kconfig"
1042
1043source "arch/arm/mach-omap2/Kconfig"
1044
1045source "arch/arm/mach-orion5x/Kconfig"
1046
1047source "arch/arm/mach-pxa/Kconfig"
1048source "arch/arm/plat-pxa/Kconfig"
1049
1050source "arch/arm/mach-mmp/Kconfig"
1051
1052source "arch/arm/mach-realview/Kconfig"
1053
1054source "arch/arm/mach-sa1100/Kconfig"
1055
1056source "arch/arm/plat-samsung/Kconfig"
1057source "arch/arm/plat-s3c24xx/Kconfig"
1058
1059source "arch/arm/plat-spear/Kconfig"
1060
1061source "arch/arm/mach-s3c24xx/Kconfig"
1062if ARCH_S3C24XX
1063source "arch/arm/mach-s3c2412/Kconfig"
1064source "arch/arm/mach-s3c2440/Kconfig"
1065endif
1066
1067if ARCH_S3C64XX
1068source "arch/arm/mach-s3c64xx/Kconfig"
1069endif
1070
1071source "arch/arm/mach-s5p64x0/Kconfig"
1072
1073source "arch/arm/mach-s5pc100/Kconfig"
1074
1075source "arch/arm/mach-s5pv210/Kconfig"
1076
1077source "arch/arm/mach-exynos/Kconfig"
1078
1079source "arch/arm/mach-shmobile/Kconfig"
1080
1081source "arch/arm/mach-tegra/Kconfig"
1082
1083source "arch/arm/mach-u300/Kconfig"
1084
1085source "arch/arm/mach-ux500/Kconfig"
1086
1087source "arch/arm/mach-versatile/Kconfig"
1088
1089source "arch/arm/mach-vexpress/Kconfig"
1090source "arch/arm/plat-versatile/Kconfig"
1091
1092source "arch/arm/mach-vt8500/Kconfig"
1093
1094source "arch/arm/mach-w90x900/Kconfig"
1095
1096# Definitions to make life easier
1097config ARCH_ACORN
1098 bool
1099
1100config PLAT_IOP
1101 bool
1102 select GENERIC_CLOCKEVENTS
1103
1104config PLAT_ORION
1105 bool
1106 select CLKSRC_MMIO
1107 select GENERIC_IRQ_CHIP
1108 select COMMON_CLK
1109
1110config PLAT_PXA
1111 bool
1112
1113config PLAT_VERSATILE
1114 bool
1115
1116config ARM_TIMER_SP804
1117 bool
1118 select CLKSRC_MMIO
1119 select HAVE_SCHED_CLOCK
1120
1121source arch/arm/mm/Kconfig
1122
1123config ARM_NR_BANKS
1124 int
1125 default 16 if ARCH_EP93XX
1126 default 8
1127
1128config IWMMXT
1129 bool "Enable iWMMXt support"
1130 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4
1131 default y if PXA27x || PXA3xx || PXA95x || ARCH_MMP
1132 help
1133 Enable support for iWMMXt context switching at run time if
1134 running on a CPU that supports it.
1135
1136config XSCALE_PMU
1137 bool
1138 depends on CPU_XSCALE
1139 default y
1140
1141config CPU_HAS_PMU
1142 depends on (CPU_V6 || CPU_V6K || CPU_V7 || XSCALE_PMU) && \
1143 (!ARCH_OMAP3 || OMAP3_EMU)
1144 default y
1145 bool
1146
1147config MULTI_IRQ_HANDLER
1148 bool
1149 help
1150 Allow each machine to specify it's own IRQ handler at run time.
1151
1152if !MMU
1153source "arch/arm/Kconfig-nommu"
1154endif
1155
1156config ARM_ERRATA_326103
1157 bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory"
1158 depends on CPU_V6
1159 help
1160 Executing a SWP instruction to read-only memory does not set bit 11
1161 of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to
1162 treat the access as a read, preventing a COW from occurring and
1163 causing the faulting task to livelock.
1164
1165config ARM_ERRATA_411920
1166 bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
1167 depends on CPU_V6 || CPU_V6K
1168 help
1169 Invalidation of the Instruction Cache operation can
1170 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
1171 It does not affect the MPCore. This option enables the ARM Ltd.
1172 recommended workaround.
1173
1174config ARM_ERRATA_430973
1175 bool "ARM errata: Stale prediction on replaced interworking branch"
1176 depends on CPU_V7
1177 help
1178 This option enables the workaround for the 430973 Cortex-A8
1179 (r1p0..r1p2) erratum. If a code sequence containing an ARM/Thumb
1180 interworking branch is replaced with another code sequence at the
1181 same virtual address, whether due to self-modifying code or virtual
1182 to physical address re-mapping, Cortex-A8 does not recover from the
1183 stale interworking branch prediction. This results in Cortex-A8
1184 executing the new code sequence in the incorrect ARM or Thumb state.
1185 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
1186 and also flushes the branch target cache at every context switch.
1187 Note that setting specific bits in the ACTLR register may not be
1188 available in non-secure mode.
1189
1190config ARM_ERRATA_458693
1191 bool "ARM errata: Processor deadlock when a false hazard is created"
1192 depends on CPU_V7
1193 help
1194 This option enables the workaround for the 458693 Cortex-A8 (r2p0)
1195 erratum. For very specific sequences of memory operations, it is
1196 possible for a hazard condition intended for a cache line to instead
1197 be incorrectly associated with a different cache line. This false
1198 hazard might then cause a processor deadlock. The workaround enables
1199 the L1 caching of the NEON accesses and disables the PLD instruction
1200 in the ACTLR register. Note that setting specific bits in the ACTLR
1201 register may not be available in non-secure mode.
1202
1203config ARM_ERRATA_460075
1204 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
1205 depends on CPU_V7
1206 help
1207 This option enables the workaround for the 460075 Cortex-A8 (r2p0)
1208 erratum. Any asynchronous access to the L2 cache may encounter a
1209 situation in which recent store transactions to the L2 cache are lost
1210 and overwritten with stale memory contents from external memory. The
1211 workaround disables the write-allocate mode for the L2 cache via the
1212 ACTLR register. Note that setting specific bits in the ACTLR register
1213 may not be available in non-secure mode.
1214
1215config ARM_ERRATA_742230
1216 bool "ARM errata: DMB operation may be faulty"
1217 depends on CPU_V7 && SMP
1218 help
1219 This option enables the workaround for the 742230 Cortex-A9
1220 (r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction
1221 between two write operations may not ensure the correct visibility
1222 ordering of the two writes. This workaround sets a specific bit in
1223 the diagnostic register of the Cortex-A9 which causes the DMB
1224 instruction to behave as a DSB, ensuring the correct behaviour of
1225 the two writes.
1226
1227config ARM_ERRATA_742231
1228 bool "ARM errata: Incorrect hazard handling in the SCU may lead to data corruption"
1229 depends on CPU_V7 && SMP
1230 help
1231 This option enables the workaround for the 742231 Cortex-A9
1232 (r2p0..r2p2) erratum. Under certain conditions, specific to the
1233 Cortex-A9 MPCore micro-architecture, two CPUs working in SMP mode,
1234 accessing some data located in the same cache line, may get corrupted
1235 data due to bad handling of the address hazard when the line gets
1236 replaced from one of the CPUs at the same time as another CPU is
1237 accessing it. This workaround sets specific bits in the diagnostic
1238 register of the Cortex-A9 which reduces the linefill issuing
1239 capabilities of the processor.
1240
1241config PL310_ERRATA_588369
1242 bool "PL310 errata: Clean & Invalidate maintenance operations do not invalidate clean lines"
1243 depends on CACHE_L2X0
1244 help
1245 The PL310 L2 cache controller implements three types of Clean &
1246 Invalidate maintenance operations: by Physical Address
1247 (offset 0x7F0), by Index/Way (0x7F8) and by Way (0x7FC).
1248 They are architecturally defined to behave as the execution of a
1249 clean operation followed immediately by an invalidate operation,
1250 both performing to the same memory location. This functionality
1251 is not correctly implemented in PL310 as clean lines are not
1252 invalidated as a result of these operations.
1253
1254config ARM_ERRATA_720789
1255 bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID"
1256 depends on CPU_V7
1257 help
1258 This option enables the workaround for the 720789 Cortex-A9 (prior to
1259 r2p0) erratum. A faulty ASID can be sent to the other CPUs for the
1260 broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS.
1261 As a consequence of this erratum, some TLB entries which should be
1262 invalidated are not, resulting in an incoherency in the system page
1263 tables. The workaround changes the TLB flushing routines to invalidate
1264 entries regardless of the ASID.
1265
1266config PL310_ERRATA_727915
1267 bool "PL310 errata: Background Clean & Invalidate by Way operation can cause data corruption"
1268 depends on CACHE_L2X0
1269 help
1270 PL310 implements the Clean & Invalidate by Way L2 cache maintenance
1271 operation (offset 0x7FC). This operation runs in background so that
1272 PL310 can handle normal accesses while it is in progress. Under very
1273 rare circumstances, due to this erratum, write data can be lost when
1274 PL310 treats a cacheable write transaction during a Clean &
1275 Invalidate by Way operation.
1276
1277config ARM_ERRATA_743622
1278 bool "ARM errata: Faulty hazard checking in the Store Buffer may lead to data corruption"
1279 depends on CPU_V7
1280 help
1281 This option enables the workaround for the 743622 Cortex-A9
1282 (r2p*) erratum. Under very rare conditions, a faulty
1283 optimisation in the Cortex-A9 Store Buffer may lead to data
1284 corruption. This workaround sets a specific bit in the diagnostic
1285 register of the Cortex-A9 which disables the Store Buffer
1286 optimisation, preventing the defect from occurring. This has no
1287 visible impact on the overall performance or power consumption of the
1288 processor.
1289
1290config ARM_ERRATA_751472
1291 bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation"
1292 depends on CPU_V7
1293 help
1294 This option enables the workaround for the 751472 Cortex-A9 (prior
1295 to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the
1296 completion of a following broadcasted operation if the second
1297 operation is received by a CPU before the ICIALLUIS has completed,
1298 potentially leading to corrupted entries in the cache or TLB.
1299
1300config PL310_ERRATA_753970
1301 bool "PL310 errata: cache sync operation may be faulty"
1302 depends on CACHE_PL310
1303 help
1304 This option enables the workaround for the 753970 PL310 (r3p0) erratum.
1305
1306 Under some condition the effect of cache sync operation on
1307 the store buffer still remains when the operation completes.
1308 This means that the store buffer is always asked to drain and
1309 this prevents it from merging any further writes. The workaround
1310 is to replace the normal offset of cache sync operation (0x730)
1311 by another offset targeting an unmapped PL310 register 0x740.
1312 This has the same effect as the cache sync operation: store buffer
1313 drain and waiting for all buffers empty.
1314
1315config ARM_ERRATA_754322
1316 bool "ARM errata: possible faulty MMU translations following an ASID switch"
1317 depends on CPU_V7
1318 help
1319 This option enables the workaround for the 754322 Cortex-A9 (r2p*,
1320 r3p*) erratum. A speculative memory access may cause a page table walk
1321 which starts prior to an ASID switch but completes afterwards. This
1322 can populate the micro-TLB with a stale entry which may be hit with
1323 the new ASID. This workaround places two dsb instructions in the mm
1324 switching code so that no page table walks can cross the ASID switch.
1325
1326config ARM_ERRATA_754327
1327 bool "ARM errata: no automatic Store Buffer drain"
1328 depends on CPU_V7 && SMP
1329 help
1330 This option enables the workaround for the 754327 Cortex-A9 (prior to
1331 r2p0) erratum. The Store Buffer does not have any automatic draining
1332 mechanism and therefore a livelock may occur if an external agent
1333 continuously polls a memory location waiting to observe an update.
1334 This workaround defines cpu_relax() as smp_mb(), preventing correctly
1335 written polling loops from denying visibility of updates to memory.
1336
1337config ARM_ERRATA_364296
1338 bool "ARM errata: Possible cache data corruption with hit-under-miss enabled"
1339 depends on CPU_V6 && !SMP
1340 help
1341 This options enables the workaround for the 364296 ARM1136
1342 r0p2 erratum (possible cache data corruption with
1343 hit-under-miss enabled). It sets the undocumented bit 31 in
1344 the auxiliary control register and the FI bit in the control
1345 register, thus disabling hit-under-miss without putting the
1346 processor into full low interrupt latency mode. ARM11MPCore
1347 is not affected.
1348
1349config ARM_ERRATA_764369
1350 bool "ARM errata: Data cache line maintenance operation by MVA may not succeed"
1351 depends on CPU_V7 && SMP
1352 help
1353 This option enables the workaround for erratum 764369
1354 affecting Cortex-A9 MPCore with two or more processors (all
1355 current revisions). Under certain timing circumstances, a data
1356 cache line maintenance operation by MVA targeting an Inner
1357 Shareable memory region may fail to proceed up to either the
1358 Point of Coherency or to the Point of Unification of the
1359 system. This workaround adds a DSB instruction before the
1360 relevant cache maintenance functions and sets a specific bit
1361 in the diagnostic control register of the SCU.
1362
1363config PL310_ERRATA_769419
1364 bool "PL310 errata: no automatic Store Buffer drain"
1365 depends on CACHE_L2X0
1366 help
1367 On revisions of the PL310 prior to r3p2, the Store Buffer does
1368 not automatically drain. This can cause normal, non-cacheable
1369 writes to be retained when the memory system is idle, leading
1370 to suboptimal I/O performance for drivers using coherent DMA.
1371 This option adds a write barrier to the cpu_idle loop so that,
1372 on systems with an outer cache, the store buffer is drained
1373 explicitly.
1374
1375endmenu
1376
1377source "arch/arm/common/Kconfig"
1378
1379menu "Bus support"
1380
1381config ARM_AMBA
1382 bool
1383
1384config ISA
1385 bool
1386 help
1387 Find out whether you have ISA slots on your motherboard. ISA is the
1388 name of a bus system, i.e. the way the CPU talks to the other stuff
1389 inside your box. Other bus systems are PCI, EISA, MicroChannel
1390 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1391 newer boards don't support it. If you have ISA, say Y, otherwise N.
1392
1393# Select ISA DMA controller support
1394config ISA_DMA
1395 bool
1396 select ISA_DMA_API
1397
1398# Select ISA DMA interface
1399config ISA_DMA_API
1400 bool
1401
1402config PCI
1403 bool "PCI support" if MIGHT_HAVE_PCI
1404 help
1405 Find out whether you have a PCI motherboard. PCI is the name of a
1406 bus system, i.e. the way the CPU talks to the other stuff inside
1407 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1408 VESA. If you have PCI, say Y, otherwise N.
1409
1410config PCI_DOMAINS
1411 bool
1412 depends on PCI
1413
1414config PCI_NANOENGINE
1415 bool "BSE nanoEngine PCI support"
1416 depends on SA1100_NANOENGINE
1417 help
1418 Enable PCI on the BSE nanoEngine board.
1419
1420config PCI_SYSCALL
1421 def_bool PCI
1422
1423# Select the host bridge type
1424config PCI_HOST_VIA82C505
1425 bool
1426 depends on PCI && ARCH_SHARK
1427 default y
1428
1429config PCI_HOST_ITE8152
1430 bool
1431 depends on PCI && MACH_ARMCORE
1432 default y
1433 select DMABOUNCE
1434
1435source "drivers/pci/Kconfig"
1436
1437source "drivers/pcmcia/Kconfig"
1438
1439endmenu
1440
1441menu "Kernel Features"
1442
1443config HAVE_SMP
1444 bool
1445 help
1446 This option should be selected by machines which have an SMP-
1447 capable CPU.
1448
1449 The only effect of this option is to make the SMP-related
1450 options available to the user for configuration.
1451
1452config SMP
1453 bool "Symmetric Multi-Processing"
1454 depends on CPU_V6K || CPU_V7
1455 depends on GENERIC_CLOCKEVENTS
1456 depends on HAVE_SMP
1457 depends on MMU
1458 select USE_GENERIC_SMP_HELPERS
1459 select HAVE_ARM_SCU if !ARCH_MSM_SCORPIONMP
1460 help
1461 This enables support for systems with more than one CPU. If you have
1462 a system with only one CPU, like most personal computers, say N. If
1463 you have a system with more than one CPU, say Y.
1464
1465 If you say N here, the kernel will run on single and multiprocessor
1466 machines, but will use only one CPU of a multiprocessor machine. If
1467 you say Y here, the kernel will run on many, but not all, single
1468 processor machines. On a single processor machine, the kernel will
1469 run faster if you say N here.
1470
1471 See also <file:Documentation/x86/i386/IO-APIC.txt>,
1472 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
1473 <http://tldp.org/HOWTO/SMP-HOWTO.html>.
1474
1475 If you don't know what to do here, say N.
1476
1477config SMP_ON_UP
1478 bool "Allow booting SMP kernel on uniprocessor systems (EXPERIMENTAL)"
1479 depends on EXPERIMENTAL
1480 depends on SMP && !XIP_KERNEL
1481 default y
1482 help
1483 SMP kernels contain instructions which fail on non-SMP processors.
1484 Enabling this option allows the kernel to modify itself to make
1485 these instructions safe. Disabling it allows about 1K of space
1486 savings.
1487
1488 If you don't know what to do here, say Y.
1489
1490config ARM_CPU_TOPOLOGY
1491 bool "Support cpu topology definition"
1492 depends on SMP && CPU_V7
1493 default y
1494 help
1495 Support ARM cpu topology definition. The MPIDR register defines
1496 affinity between processors which is then used to describe the cpu
1497 topology of an ARM System.
1498
1499config SCHED_MC
1500 bool "Multi-core scheduler support"
1501 depends on ARM_CPU_TOPOLOGY
1502 help
1503 Multi-core scheduler support improves the CPU scheduler's decision
1504 making when dealing with multi-core CPU chips at a cost of slightly
1505 increased overhead in some places. If unsure say N here.
1506
1507config SCHED_SMT
1508 bool "SMT scheduler support"
1509 depends on ARM_CPU_TOPOLOGY
1510 help
1511 Improves the CPU scheduler's decision making when dealing with
1512 MultiThreading at a cost of slightly increased overhead in some
1513 places. If unsure say N here.
1514
1515config HAVE_ARM_SCU
1516 bool
1517 help
1518 This option enables support for the ARM system coherency unit
1519
1520config ARM_ARCH_TIMER
1521 bool "Architected timer support"
1522 depends on CPU_V7
1523 help
1524 This option enables support for the ARM architected timer
1525
1526config HAVE_ARM_TWD
1527 bool
1528 depends on SMP
1529 help
1530 This options enables support for the ARM timer and watchdog unit
1531
1532choice
1533 prompt "Memory split"
1534 default VMSPLIT_3G
1535 help
1536 Select the desired split between kernel and user memory.
1537
1538 If you are not absolutely sure what you are doing, leave this
1539 option alone!
1540
1541 config VMSPLIT_3G
1542 bool "3G/1G user/kernel split"
1543 config VMSPLIT_2G
1544 bool "2G/2G user/kernel split"
1545 config VMSPLIT_1G
1546 bool "1G/3G user/kernel split"
1547endchoice
1548
1549config PAGE_OFFSET
1550 hex
1551 default 0x40000000 if VMSPLIT_1G
1552 default 0x80000000 if VMSPLIT_2G
1553 default 0xC0000000
1554
1555config NR_CPUS
1556 int "Maximum number of CPUs (2-32)"
1557 range 2 32
1558 depends on SMP
1559 default "4"
1560
1561config HOTPLUG_CPU
1562 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
1563 depends on SMP && HOTPLUG && EXPERIMENTAL
1564 help
1565 Say Y here to experiment with turning CPUs off and on. CPUs
1566 can be controlled through /sys/devices/system/cpu.
1567
1568config LOCAL_TIMERS
1569 bool "Use local timer interrupts"
1570 depends on SMP
1571 default y
1572 select HAVE_ARM_TWD if (!ARCH_MSM_SCORPIONMP && !EXYNOS4_MCT)
1573 help
1574 Enable support for local timers on SMP platforms, rather then the
1575 legacy IPI broadcast method. Local timers allows the system
1576 accounting to be spread across the timer interval, preventing a
1577 "thundering herd" at every timer tick.
1578
1579config ARCH_NR_GPIO
1580 int
1581 default 1024 if ARCH_SHMOBILE || ARCH_TEGRA
1582 default 355 if ARCH_U8500
1583 default 264 if MACH_H4700
1584 default 0
1585 help
1586 Maximum number of GPIOs in the system.
1587
1588 If unsure, leave the default value.
1589
1590source kernel/Kconfig.preempt
1591
1592config HZ
1593 int
1594 default 200 if ARCH_EBSA110 || ARCH_S3C24XX || ARCH_S5P64X0 || \
1595 ARCH_S5PV210 || ARCH_EXYNOS4
1596 default OMAP_32K_TIMER_HZ if ARCH_OMAP && OMAP_32K_TIMER
1597 default AT91_TIMER_HZ if ARCH_AT91
1598 default SHMOBILE_TIMER_HZ if ARCH_SHMOBILE
1599 default 100
1600
1601config THUMB2_KERNEL
1602 bool "Compile the kernel in Thumb-2 mode (EXPERIMENTAL)"
1603 depends on CPU_V7 && !CPU_V6 && !CPU_V6K && EXPERIMENTAL
1604 select AEABI
1605 select ARM_ASM_UNIFIED
1606 select ARM_UNWIND
1607 help
1608 By enabling this option, the kernel will be compiled in
1609 Thumb-2 mode. A compiler/assembler that understand the unified
1610 ARM-Thumb syntax is needed.
1611
1612 If unsure, say N.
1613
1614config THUMB2_AVOID_R_ARM_THM_JUMP11
1615 bool "Work around buggy Thumb-2 short branch relocations in gas"
1616 depends on THUMB2_KERNEL && MODULES
1617 default y
1618 help
1619 Various binutils versions can resolve Thumb-2 branches to
1620 locally-defined, preemptible global symbols as short-range "b.n"
1621 branch instructions.
1622
1623 This is a problem, because there's no guarantee the final
1624 destination of the symbol, or any candidate locations for a
1625 trampoline, are within range of the branch. For this reason, the
1626 kernel does not support fixing up the R_ARM_THM_JUMP11 (102)
1627 relocation in modules at all, and it makes little sense to add
1628 support.
1629
1630 The symptom is that the kernel fails with an "unsupported
1631 relocation" error when loading some modules.
1632
1633 Until fixed tools are available, passing
1634 -fno-optimize-sibling-calls to gcc should prevent gcc generating
1635 code which hits this problem, at the cost of a bit of extra runtime
1636 stack usage in some cases.
1637
1638 The problem is described in more detail at:
1639 https://bugs.launchpad.net/binutils-linaro/+bug/725126
1640
1641 Only Thumb-2 kernels are affected.
1642
1643 Unless you are sure your tools don't have this problem, say Y.
1644
1645config ARM_ASM_UNIFIED
1646 bool
1647
1648config AEABI
1649 bool "Use the ARM EABI to compile the kernel"
1650 help
1651 This option allows for the kernel to be compiled using the latest
1652 ARM ABI (aka EABI). This is only useful if you are using a user
1653 space environment that is also compiled with EABI.
1654
1655 Since there are major incompatibilities between the legacy ABI and
1656 EABI, especially with regard to structure member alignment, this
1657 option also changes the kernel syscall calling convention to
1658 disambiguate both ABIs and allow for backward compatibility support
1659 (selected with CONFIG_OABI_COMPAT).
1660
1661 To use this you need GCC version 4.0.0 or later.
1662
1663config OABI_COMPAT
1664 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1665 depends on AEABI && EXPERIMENTAL && !THUMB2_KERNEL
1666 default y
1667 help
1668 This option preserves the old syscall interface along with the
1669 new (ARM EABI) one. It also provides a compatibility layer to
1670 intercept syscalls that have structure arguments which layout
1671 in memory differs between the legacy ABI and the new ARM EABI
1672 (only for non "thumb" binaries). This option adds a tiny
1673 overhead to all syscalls and produces a slightly larger kernel.
1674 If you know you'll be using only pure EABI user space then you
1675 can say N here. If this option is not selected and you attempt
1676 to execute a legacy ABI binary then the result will be
1677 UNPREDICTABLE (in fact it can be predicted that it won't work
1678 at all). If in doubt say Y.
1679
1680config ARCH_HAS_HOLES_MEMORYMODEL
1681 bool
1682
1683config ARCH_SPARSEMEM_ENABLE
1684 bool
1685
1686config ARCH_SPARSEMEM_DEFAULT
1687 def_bool ARCH_SPARSEMEM_ENABLE
1688
1689config ARCH_SELECT_MEMORY_MODEL
1690 def_bool ARCH_SPARSEMEM_ENABLE
1691
1692config HAVE_ARCH_PFN_VALID
1693 def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM
1694
1695config HIGHMEM
1696 bool "High Memory Support"
1697 depends on MMU
1698 help
1699 The address space of ARM processors is only 4 Gigabytes large
1700 and it has to accommodate user address space, kernel address
1701 space as well as some memory mapped IO. That means that, if you
1702 have a large amount of physical memory and/or IO, not all of the
1703 memory can be "permanently mapped" by the kernel. The physical
1704 memory that is not permanently mapped is called "high memory".
1705
1706 Depending on the selected kernel/user memory split, minimum
1707 vmalloc space and actual amount of RAM, you may not need this
1708 option which should result in a slightly faster kernel.
1709
1710 If unsure, say n.
1711
1712config HIGHPTE
1713 bool "Allocate 2nd-level pagetables from highmem"
1714 depends on HIGHMEM
1715
1716config HW_PERF_EVENTS
1717 bool "Enable hardware performance counter support for perf events"
1718 depends on PERF_EVENTS && CPU_HAS_PMU
1719 default y
1720 help
1721 Enable hardware performance counter support for perf events. If
1722 disabled, perf events will use software events only.
1723
1724source "mm/Kconfig"
1725
1726config FORCE_MAX_ZONEORDER
1727 int "Maximum zone order" if ARCH_SHMOBILE
1728 range 11 64 if ARCH_SHMOBILE
1729 default "9" if SA1111
1730 default "11"
1731 help
1732 The kernel memory allocator divides physically contiguous memory
1733 blocks into "zones", where each zone is a power of two number of
1734 pages. This option selects the largest power of two that the kernel
1735 keeps in the memory allocator. If you need to allocate very large
1736 blocks of physically contiguous memory, then you may need to
1737 increase this value.
1738
1739 This config option is actually maximum order plus one. For example,
1740 a value of 11 means that the largest free memory block is 2^10 pages.
1741
1742config LEDS
1743 bool "Timer and CPU usage LEDs"
1744 depends on ARCH_CDB89712 || ARCH_EBSA110 || \
1745 ARCH_EBSA285 || ARCH_INTEGRATOR || \
1746 ARCH_LUBBOCK || MACH_MAINSTONE || ARCH_NETWINDER || \
1747 ARCH_OMAP || ARCH_P720T || ARCH_PXA_IDP || \
1748 ARCH_SA1100 || ARCH_SHARK || ARCH_VERSATILE || \
1749 ARCH_AT91 || ARCH_DAVINCI || \
1750 ARCH_KS8695 || MACH_RD88F5182 || ARCH_REALVIEW
1751 help
1752 If you say Y here, the LEDs on your machine will be used
1753 to provide useful information about your current system status.
1754
1755 If you are compiling a kernel for a NetWinder or EBSA-285, you will
1756 be able to select which LEDs are active using the options below. If
1757 you are compiling a kernel for the EBSA-110 or the LART however, the
1758 red LED will simply flash regularly to indicate that the system is
1759 still functional. It is safe to say Y here if you have a CATS
1760 system, but the driver will do nothing.
1761
1762config LEDS_TIMER
1763 bool "Timer LED" if (!ARCH_CDB89712 && !ARCH_OMAP) || \
1764 OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1765 || MACH_OMAP_PERSEUS2
1766 depends on LEDS
1767 depends on !GENERIC_CLOCKEVENTS
1768 default y if ARCH_EBSA110
1769 help
1770 If you say Y here, one of the system LEDs (the green one on the
1771 NetWinder, the amber one on the EBSA285, or the red one on the LART)
1772 will flash regularly to indicate that the system is still
1773 operational. This is mainly useful to kernel hackers who are
1774 debugging unstable kernels.
1775
1776 The LART uses the same LED for both Timer LED and CPU usage LED
1777 functions. You may choose to use both, but the Timer LED function
1778 will overrule the CPU usage LED.
1779
1780config LEDS_CPU
1781 bool "CPU usage LED" if (!ARCH_CDB89712 && !ARCH_EBSA110 && \
1782 !ARCH_OMAP) \
1783 || OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1784 || MACH_OMAP_PERSEUS2
1785 depends on LEDS
1786 help
1787 If you say Y here, the red LED will be used to give a good real
1788 time indication of CPU usage, by lighting whenever the idle task
1789 is not currently executing.
1790
1791 The LART uses the same LED for both Timer LED and CPU usage LED
1792 functions. You may choose to use both, but the Timer LED function
1793 will overrule the CPU usage LED.
1794
1795config ALIGNMENT_TRAP
1796 bool
1797 depends on CPU_CP15_MMU
1798 default y if !ARCH_EBSA110
1799 select HAVE_PROC_CPU if PROC_FS
1800 help
1801 ARM processors cannot fetch/store information which is not
1802 naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1803 address divisible by 4. On 32-bit ARM processors, these non-aligned
1804 fetch/store instructions will be emulated in software if you say
1805 here, which has a severe performance impact. This is necessary for
1806 correct operation of some network protocols. With an IP-only
1807 configuration it is safe to say N, otherwise say Y.
1808
1809config UACCESS_WITH_MEMCPY
1810 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user() (EXPERIMENTAL)"
1811 depends on MMU && EXPERIMENTAL
1812 default y if CPU_FEROCEON
1813 help
1814 Implement faster copy_to_user and clear_user methods for CPU
1815 cores where a 8-word STM instruction give significantly higher
1816 memory write throughput than a sequence of individual 32bit stores.
1817
1818 A possible side effect is a slight increase in scheduling latency
1819 between threads sharing the same address space if they invoke
1820 such copy operations with large buffers.
1821
1822 However, if the CPU data cache is using a write-allocate mode,
1823 this option is unlikely to provide any performance gain.
1824
1825config SECCOMP
1826 bool
1827 prompt "Enable seccomp to safely compute untrusted bytecode"
1828 ---help---
1829 This kernel feature is useful for number crunching applications
1830 that may need to compute untrusted bytecode during their
1831 execution. By using pipes or other transports made available to
1832 the process as file descriptors supporting the read/write
1833 syscalls, it's possible to isolate those applications in
1834 their own address space using seccomp. Once seccomp is
1835 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1836 and the task is only allowed to execute a few safe syscalls
1837 defined by each seccomp mode.
1838
1839config CC_STACKPROTECTOR
1840 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1841 depends on EXPERIMENTAL
1842 help
1843 This option turns on the -fstack-protector GCC feature. This
1844 feature puts, at the beginning of functions, a canary value on
1845 the stack just before the return address, and validates
1846 the value just before actually returning. Stack based buffer
1847 overflows (that need to overwrite this return address) now also
1848 overwrite the canary, which gets detected and the attack is then
1849 neutralized via a kernel panic.
1850 This feature requires gcc version 4.2 or above.
1851
1852config DEPRECATED_PARAM_STRUCT
1853 bool "Provide old way to pass kernel parameters"
1854 help
1855 This was deprecated in 2001 and announced to live on for 5 years.
1856 Some old boot loaders still use this way.
1857
1858endmenu
1859
1860menu "Boot options"
1861
1862config USE_OF
1863 bool "Flattened Device Tree support"
1864 select OF
1865 select OF_EARLY_FLATTREE
1866 select IRQ_DOMAIN
1867 help
1868 Include support for flattened device tree machine descriptions.
1869
1870# Compressed boot loader in ROM. Yes, we really want to ask about
1871# TEXT and BSS so we preserve their values in the config files.
1872config ZBOOT_ROM_TEXT
1873 hex "Compressed ROM boot loader base address"
1874 default "0"
1875 help
1876 The physical address at which the ROM-able zImage is to be
1877 placed in the target. Platforms which normally make use of
1878 ROM-able zImage formats normally set this to a suitable
1879 value in their defconfig file.
1880
1881 If ZBOOT_ROM is not enabled, this has no effect.
1882
1883config ZBOOT_ROM_BSS
1884 hex "Compressed ROM boot loader BSS address"
1885 default "0"
1886 help
1887 The base address of an area of read/write memory in the target
1888 for the ROM-able zImage which must be available while the
1889 decompressor is running. It must be large enough to hold the
1890 entire decompressed kernel plus an additional 128 KiB.
1891 Platforms which normally make use of ROM-able zImage formats
1892 normally set this to a suitable value in their defconfig file.
1893
1894 If ZBOOT_ROM is not enabled, this has no effect.
1895
1896config ZBOOT_ROM
1897 bool "Compressed boot loader in ROM/flash"
1898 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1899 help
1900 Say Y here if you intend to execute your compressed kernel image
1901 (zImage) directly from ROM or flash. If unsure, say N.
1902
1903choice
1904 prompt "Include SD/MMC loader in zImage (EXPERIMENTAL)"
1905 depends on ZBOOT_ROM && ARCH_SH7372 && EXPERIMENTAL
1906 default ZBOOT_ROM_NONE
1907 help
1908 Include experimental SD/MMC loading code in the ROM-able zImage.
1909 With this enabled it is possible to write the ROM-able zImage
1910 kernel image to an MMC or SD card and boot the kernel straight
1911 from the reset vector. At reset the processor Mask ROM will load
1912 the first part of the ROM-able zImage which in turn loads the
1913 rest the kernel image to RAM.
1914
1915config ZBOOT_ROM_NONE
1916 bool "No SD/MMC loader in zImage (EXPERIMENTAL)"
1917 help
1918 Do not load image from SD or MMC
1919
1920config ZBOOT_ROM_MMCIF
1921 bool "Include MMCIF loader in zImage (EXPERIMENTAL)"
1922 help
1923 Load image from MMCIF hardware block.
1924
1925config ZBOOT_ROM_SH_MOBILE_SDHI
1926 bool "Include SuperH Mobile SDHI loader in zImage (EXPERIMENTAL)"
1927 help
1928 Load image from SDHI hardware block
1929
1930endchoice
1931
1932config ARM_APPENDED_DTB
1933 bool "Use appended device tree blob to zImage (EXPERIMENTAL)"
1934 depends on OF && !ZBOOT_ROM && EXPERIMENTAL
1935 help
1936 With this option, the boot code will look for a device tree binary
1937 (DTB) appended to zImage
1938 (e.g. cat zImage <filename>.dtb > zImage_w_dtb).
1939
1940 This is meant as a backward compatibility convenience for those
1941 systems with a bootloader that can't be upgraded to accommodate
1942 the documented boot protocol using a device tree.
1943
1944 Beware that there is very little in terms of protection against
1945 this option being confused by leftover garbage in memory that might
1946 look like a DTB header after a reboot if no actual DTB is appended
1947 to zImage. Do not leave this option active in a production kernel
1948 if you don't intend to always append a DTB. Proper passing of the
1949 location into r2 of a bootloader provided DTB is always preferable
1950 to this option.
1951
1952config ARM_ATAG_DTB_COMPAT
1953 bool "Supplement the appended DTB with traditional ATAG information"
1954 depends on ARM_APPENDED_DTB
1955 help
1956 Some old bootloaders can't be updated to a DTB capable one, yet
1957 they provide ATAGs with memory configuration, the ramdisk address,
1958 the kernel cmdline string, etc. Such information is dynamically
1959 provided by the bootloader and can't always be stored in a static
1960 DTB. To allow a device tree enabled kernel to be used with such
1961 bootloaders, this option allows zImage to extract the information
1962 from the ATAG list and store it at run time into the appended DTB.
1963
1964config CMDLINE
1965 string "Default kernel command string"
1966 default ""
1967 help
1968 On some architectures (EBSA110 and CATS), there is currently no way
1969 for the boot loader to pass arguments to the kernel. For these
1970 architectures, you should supply some command-line options at build
1971 time by entering them here. As a minimum, you should specify the
1972 memory size and the root device (e.g., mem=64M root=/dev/nfs).
1973
1974choice
1975 prompt "Kernel command line type" if CMDLINE != ""
1976 default CMDLINE_FROM_BOOTLOADER
1977
1978config CMDLINE_FROM_BOOTLOADER
1979 bool "Use bootloader kernel arguments if available"
1980 help
1981 Uses the command-line options passed by the boot loader. If
1982 the boot loader doesn't provide any, the default kernel command
1983 string provided in CMDLINE will be used.
1984
1985config CMDLINE_EXTEND
1986 bool "Extend bootloader kernel arguments"
1987 help
1988 The command-line arguments provided by the boot loader will be
1989 appended to the default kernel command string.
1990
1991config CMDLINE_FORCE
1992 bool "Always use the default kernel command string"
1993 help
1994 Always use the default kernel command string, even if the boot
1995 loader passes other arguments to the kernel.
1996 This is useful if you cannot or don't want to change the
1997 command-line options your boot loader passes to the kernel.
1998endchoice
1999
2000config XIP_KERNEL
2001 bool "Kernel Execute-In-Place from ROM"
2002 depends on !ZBOOT_ROM && !ARM_LPAE
2003 help
2004 Execute-In-Place allows the kernel to run from non-volatile storage
2005 directly addressable by the CPU, such as NOR flash. This saves RAM
2006 space since the text section of the kernel is not loaded from flash
2007 to RAM. Read-write sections, such as the data section and stack,
2008 are still copied to RAM. The XIP kernel is not compressed since
2009 it has to run directly from flash, so it will take more space to
2010 store it. The flash address used to link the kernel object files,
2011 and for storing it, is configuration dependent. Therefore, if you
2012 say Y here, you must know the proper physical address where to
2013 store the kernel image depending on your own flash memory usage.
2014
2015 Also note that the make target becomes "make xipImage" rather than
2016 "make zImage" or "make Image". The final kernel binary to put in
2017 ROM memory will be arch/arm/boot/xipImage.
2018
2019 If unsure, say N.
2020
2021config XIP_PHYS_ADDR
2022 hex "XIP Kernel Physical Location"
2023 depends on XIP_KERNEL
2024 default "0x00080000"
2025 help
2026 This is the physical address in your flash memory the kernel will
2027 be linked for and stored to. This address is dependent on your
2028 own flash usage.
2029
2030config KEXEC
2031 bool "Kexec system call (EXPERIMENTAL)"
2032 depends on EXPERIMENTAL && (!SMP || HOTPLUG_CPU)
2033 help
2034 kexec is a system call that implements the ability to shutdown your
2035 current kernel, and to start another kernel. It is like a reboot
2036 but it is independent of the system firmware. And like a reboot
2037 you can start any kernel with it, not just Linux.
2038
2039 It is an ongoing process to be certain the hardware in a machine
2040 is properly shutdown, so do not be surprised if this code does not
2041 initially work for you. It may help to enable device hotplugging
2042 support.
2043
2044config ATAGS_PROC
2045 bool "Export atags in procfs"
2046 depends on KEXEC
2047 default y
2048 help
2049 Should the atags used to boot the kernel be exported in an "atags"
2050 file in procfs. Useful with kexec.
2051
2052config CRASH_DUMP
2053 bool "Build kdump crash kernel (EXPERIMENTAL)"
2054 depends on EXPERIMENTAL
2055 help
2056 Generate crash dump after being started by kexec. This should
2057 be normally only set in special crash dump kernels which are
2058 loaded in the main kernel with kexec-tools into a specially
2059 reserved region and then later executed after a crash by
2060 kdump/kexec. The crash dump kernel must be compiled to a
2061 memory address not used by the main kernel
2062
2063 For more details see Documentation/kdump/kdump.txt
2064
2065config AUTO_ZRELADDR
2066 bool "Auto calculation of the decompressed kernel image address"
2067 depends on !ZBOOT_ROM && !ARCH_U300
2068 help
2069 ZRELADDR is the physical address where the decompressed kernel
2070 image will be placed. If AUTO_ZRELADDR is selected, the address
2071 will be determined at run-time by masking the current IP with
2072 0xf8000000. This assumes the zImage being placed in the first 128MB
2073 from start of memory.
2074
2075endmenu
2076
2077menu "CPU Power Management"
2078
2079if ARCH_HAS_CPUFREQ
2080
2081source "drivers/cpufreq/Kconfig"
2082
2083config CPU_FREQ_IMX
2084 tristate "CPUfreq driver for i.MX CPUs"
2085 depends on ARCH_MXC && CPU_FREQ
2086 select CPU_FREQ_TABLE
2087 help
2088 This enables the CPUfreq driver for i.MX CPUs.
2089
2090config CPU_FREQ_SA1100
2091 bool
2092
2093config CPU_FREQ_SA1110
2094 bool
2095
2096config CPU_FREQ_INTEGRATOR
2097 tristate "CPUfreq driver for ARM Integrator CPUs"
2098 depends on ARCH_INTEGRATOR && CPU_FREQ
2099 default y
2100 help
2101 This enables the CPUfreq driver for ARM Integrator CPUs.
2102
2103 For details, take a look at <file:Documentation/cpu-freq>.
2104
2105 If in doubt, say Y.
2106
2107config CPU_FREQ_PXA
2108 bool
2109 depends on CPU_FREQ && ARCH_PXA && PXA25x
2110 default y
2111 select CPU_FREQ_TABLE
2112 select CPU_FREQ_DEFAULT_GOV_USERSPACE
2113
2114config CPU_FREQ_S3C
2115 bool
2116 help
2117 Internal configuration node for common cpufreq on Samsung SoC
2118
2119config CPU_FREQ_S3C24XX
2120 bool "CPUfreq driver for Samsung S3C24XX series CPUs (EXPERIMENTAL)"
2121 depends on ARCH_S3C24XX && CPU_FREQ && EXPERIMENTAL
2122 select CPU_FREQ_S3C
2123 help
2124 This enables the CPUfreq driver for the Samsung S3C24XX family
2125 of CPUs.
2126
2127 For details, take a look at <file:Documentation/cpu-freq>.
2128
2129 If in doubt, say N.
2130
2131config CPU_FREQ_S3C24XX_PLL
2132 bool "Support CPUfreq changing of PLL frequency (EXPERIMENTAL)"
2133 depends on CPU_FREQ_S3C24XX && EXPERIMENTAL
2134 help
2135 Compile in support for changing the PLL frequency from the
2136 S3C24XX series CPUfreq driver. The PLL takes time to settle
2137 after a frequency change, so by default it is not enabled.
2138
2139 This also means that the PLL tables for the selected CPU(s) will
2140 be built which may increase the size of the kernel image.
2141
2142config CPU_FREQ_S3C24XX_DEBUG
2143 bool "Debug CPUfreq Samsung driver core"
2144 depends on CPU_FREQ_S3C24XX
2145 help
2146 Enable s3c_freq_dbg for the Samsung S3C CPUfreq core
2147
2148config CPU_FREQ_S3C24XX_IODEBUG
2149 bool "Debug CPUfreq Samsung driver IO timing"
2150 depends on CPU_FREQ_S3C24XX
2151 help
2152 Enable s3c_freq_iodbg for the Samsung S3C CPUfreq core
2153
2154config CPU_FREQ_S3C24XX_DEBUGFS
2155 bool "Export debugfs for CPUFreq"
2156 depends on CPU_FREQ_S3C24XX && DEBUG_FS
2157 help
2158 Export status information via debugfs.
2159
2160endif
2161
2162source "drivers/cpuidle/Kconfig"
2163
2164endmenu
2165
2166menu "Floating point emulation"
2167
2168comment "At least one emulation must be selected"
2169
2170config FPE_NWFPE
2171 bool "NWFPE math emulation"
2172 depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL
2173 ---help---
2174 Say Y to include the NWFPE floating point emulator in the kernel.
2175 This is necessary to run most binaries. Linux does not currently
2176 support floating point hardware so you need to say Y here even if
2177 your machine has an FPA or floating point co-processor podule.
2178
2179 You may say N here if you are going to load the Acorn FPEmulator
2180 early in the bootup.
2181
2182config FPE_NWFPE_XP
2183 bool "Support extended precision"
2184 depends on FPE_NWFPE
2185 help
2186 Say Y to include 80-bit support in the kernel floating-point
2187 emulator. Otherwise, only 32 and 64-bit support is compiled in.
2188 Note that gcc does not generate 80-bit operations by default,
2189 so in most cases this option only enlarges the size of the
2190 floating point emulator without any good reason.
2191
2192 You almost surely want to say N here.
2193
2194config FPE_FASTFPE
2195 bool "FastFPE math emulation (EXPERIMENTAL)"
2196 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3 && EXPERIMENTAL
2197 ---help---
2198 Say Y here to include the FAST floating point emulator in the kernel.
2199 This is an experimental much faster emulator which now also has full
2200 precision for the mantissa. It does not support any exceptions.
2201 It is very simple, and approximately 3-6 times faster than NWFPE.
2202
2203 It should be sufficient for most programs. It may be not suitable
2204 for scientific calculations, but you have to check this for yourself.
2205 If you do not feel you need a faster FP emulation you should better
2206 choose NWFPE.
2207
2208config VFP
2209 bool "VFP-format floating point maths"
2210 depends on CPU_V6 || CPU_V6K || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
2211 help
2212 Say Y to include VFP support code in the kernel. This is needed
2213 if your hardware includes a VFP unit.
2214
2215 Please see <file:Documentation/arm/VFP/release-notes.txt> for
2216 release notes and additional status information.
2217
2218 Say N if your target does not have VFP hardware.
2219
2220config VFPv3
2221 bool
2222 depends on VFP
2223 default y if CPU_V7
2224
2225config NEON
2226 bool "Advanced SIMD (NEON) Extension support"
2227 depends on VFPv3 && CPU_V7
2228 help
2229 Say Y to include support code for NEON, the ARMv7 Advanced SIMD
2230 Extension.
2231
2232endmenu
2233
2234menu "Userspace binary formats"
2235
2236source "fs/Kconfig.binfmt"
2237
2238config ARTHUR
2239 tristate "RISC OS personality"
2240 depends on !AEABI
2241 help
2242 Say Y here to include the kernel code necessary if you want to run
2243 Acorn RISC OS/Arthur binaries under Linux. This code is still very
2244 experimental; if this sounds frightening, say N and sleep in peace.
2245 You can also say M here to compile this support as a module (which
2246 will be called arthur).
2247
2248endmenu
2249
2250menu "Power management options"
2251
2252source "kernel/power/Kconfig"
2253
2254config ARCH_SUSPEND_POSSIBLE
2255 depends on !ARCH_S5PC100 && !ARCH_TEGRA
2256 depends on CPU_ARM920T || CPU_ARM926T || CPU_SA1100 || \
2257 CPU_V6 || CPU_V6K || CPU_V7 || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK
2258 def_bool y
2259
2260config ARM_CPU_SUSPEND
2261 def_bool PM_SLEEP
2262
2263endmenu
2264
2265source "net/Kconfig"
2266
2267source "drivers/Kconfig"
2268
2269source "fs/Kconfig"
2270
2271source "arch/arm/Kconfig.debug"
2272
2273source "security/Kconfig"
2274
2275source "crypto/Kconfig"
2276
2277source "lib/Kconfig"