blob: ac0d57ee9ba71bd0e0497ad9d24ec7ffa645387b [file] [log] [blame]
b.liue9582032025-04-17 19:18:16 +08001# SPDX-License-Identifier: GPL-2.0
2config ARM
3 bool
4 default y
5 select ARCH_32BIT_OFF_T
6 select ARCH_CLOCKSOURCE_DATA
7 select ARCH_HAS_BINFMT_FLAT
8 select ARCH_HAS_CPU_FINALIZE_INIT if MMU
9 select ARCH_HAS_DEBUG_VIRTUAL if MMU
10 select ARCH_HAS_DEVMEM_IS_ALLOWED
11 select ARCH_HAS_DMA_COHERENT_TO_PFN if SWIOTLB
12 select ARCH_HAS_DMA_WRITE_COMBINE if !ARM_DMA_MEM_BUFFERABLE
13 select ARCH_HAS_ELF_RANDOMIZE
14 select ARCH_HAS_FORTIFY_SOURCE
15 select ARCH_HAS_KEEPINITRD
16 select ARCH_HAS_KCOV
17 select ARCH_HAS_MEMBARRIER_SYNC_CORE
18 select ARCH_HAS_PTE_SPECIAL if ARM_LPAE
19 select ARCH_HAS_PHYS_TO_DMA
20 select ARCH_HAS_SETUP_DMA_OPS
21 select ARCH_HAS_SET_MEMORY
22 select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
23 select ARCH_HAS_STRICT_MODULE_RWX if MMU
24 select ARCH_HAS_SYNC_DMA_FOR_DEVICE if SWIOTLB
25 select ARCH_HAS_SYNC_DMA_FOR_CPU if SWIOTLB
26 select ARCH_HAS_TEARDOWN_DMA_OPS if MMU
27 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
28 select ARCH_HAVE_CUSTOM_GPIO_H
29 select ARCH_HAS_GCOV_PROFILE_ALL
30 select ARCH_KEEP_MEMBLOCK
31 select ARCH_MIGHT_HAVE_PC_PARPORT
32 select ARCH_NO_SG_CHAIN if !ARM_HAS_SG_CHAIN
33 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
34 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT if CPU_V7
35 select ARCH_SUPPORTS_ATOMIC_RMW
36 select ARCH_USE_BUILTIN_BSWAP
37 select ARCH_USE_CMPXCHG_LOCKREF
38 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT if MMU
39 select ARCH_WANT_IPC_PARSE_VERSION
40 select BINFMT_FLAT_ARGVP_ENVP_ON_STACK
41 select BUILDTIME_EXTABLE_SORT if MMU
42 select CLONE_BACKWARDS
43 select CPU_PM if SUSPEND || CPU_IDLE
44 select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS
45 select DMA_DECLARE_COHERENT
46 select DMA_REMAP if MMU
47 select EDAC_SUPPORT
48 select EDAC_ATOMIC_SCRUB
49 select GENERIC_ALLOCATOR
50 select GENERIC_ARCH_TOPOLOGY if ARM_CPU_TOPOLOGY
51 select GENERIC_ATOMIC64 if CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI
52 select GENERIC_CLOCKEVENTS_BROADCAST if SMP
53 select GENERIC_IRQ_IPI if SMP
54 select GENERIC_CPU_AUTOPROBE
55 select GENERIC_EARLY_IOREMAP
56 select GENERIC_IDLE_POLL_SETUP
57 select GENERIC_IRQ_PROBE
58 select GENERIC_IRQ_SHOW
59 select GENERIC_IRQ_SHOW_LEVEL
60 select GENERIC_PCI_IOMAP
61 select GENERIC_SCHED_CLOCK
62 select GENERIC_SMP_IDLE_THREAD
63 select GENERIC_STRNCPY_FROM_USER
64 select GENERIC_STRNLEN_USER
65 select HANDLE_DOMAIN_IRQ
66 select HARDIRQS_SW_RESEND
67 select HAVE_ARCH_AUDITSYSCALL if AEABI && !OABI_COMPAT
68 select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
69 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
70 select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
71 select HAVE_ARCH_MMAP_RND_BITS if MMU
72 select HAVE_ARCH_SECCOMP_FILTER if AEABI && !OABI_COMPAT
73 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
74 select HAVE_ARCH_TRACEHOOK
75 select HAVE_ARM_SMCCC if CPU_V7
76 select HAVE_EBPF_JIT if !CPU_ENDIAN_BE32
77 select HAVE_CONTEXT_TRACKING
78 select HAVE_COPY_THREAD_TLS
79 select HAVE_C_RECORDMCOUNT
80 select HAVE_DEBUG_KMEMLEAK if !XIP_KERNEL
81 select HAVE_DMA_CONTIGUOUS if MMU
82 select HAVE_DYNAMIC_FTRACE if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
83 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
84 select HAVE_EFFICIENT_UNALIGNED_ACCESS if (CPU_V6 || CPU_V6K || CPU_V7) && MMU
85 select HAVE_EXIT_THREAD
86 select HAVE_FAST_GUP if ARM_LPAE
87 select HAVE_FTRACE_MCOUNT_RECORD if !XIP_KERNEL
88 select HAVE_FUNCTION_GRAPH_TRACER
89 select HAVE_FUNCTION_TRACER if !XIP_KERNEL && (CC_IS_GCC || CLANG_VERSION >= 100000)
90 select HAVE_FUTEX_CMPXCHG if FUTEX
91 select HAVE_GCC_PLUGINS
92 select HAVE_HW_BREAKPOINT if PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7)
93 select HAVE_IDE if PCI || ISA || PCMCIA
94 select HAVE_IRQ_TIME_ACCOUNTING
95 select HAVE_KERNEL_GZIP
96 select HAVE_KERNEL_LZ4
97 select HAVE_KERNEL_LZMA
98 select HAVE_KERNEL_LZO
99 select HAVE_KERNEL_XZ
100 select HAVE_KPROBES if !XIP_KERNEL && !CPU_ENDIAN_BE32 && !CPU_V7M
101 select HAVE_KRETPROBES if HAVE_KPROBES
102 select HAVE_LD_DEAD_CODE_DATA_ELIMINATION
103 select HAVE_MOD_ARCH_SPECIFIC
104 select HAVE_NMI
105 select HAVE_OPROFILE if HAVE_PERF_EVENTS
106 select HAVE_OPTPROBES if !THUMB2_KERNEL
107 select HAVE_PERF_EVENTS
108 select HAVE_PERF_REGS
109 select HAVE_PERF_USER_STACK_DUMP
110 select HAVE_RCU_TABLE_FREE if SMP && ARM_LPAE
111 select HAVE_REGS_AND_STACK_ACCESS_API
112 select HAVE_RSEQ
113 select HAVE_STACKPROTECTOR
114 select HAVE_SYSCALL_TRACEPOINTS
115 select HAVE_UID16
116 select HAVE_VIRT_CPU_ACCOUNTING_GEN
117 select IRQ_FORCED_THREADING
118 select HAVE_LD_DEAD_CODE_DATA_ELIMINATION
119 select MODULES_USE_ELF_REL
120 select NEED_DMA_MAP_STATE
121 select OF_EARLY_FLATTREE if OF
122 select OLD_SIGACTION
123 select OLD_SIGSUSPEND3
124 select PCI_SYSCALL if PCI
125 select PERF_USE_VMALLOC
126 select RTC_LIB
127 select SYS_SUPPORTS_APM_EMULATION
128 # Above selects are sorted alphabetically; please add new ones
129 # according to that. Thanks.
130 help
131 The ARM series is a line of low-power-consumption RISC chip designs
132 licensed by ARM Ltd and targeted at embedded applications and
133 handhelds such as the Compaq IPAQ. ARM-based PCs are no longer
134 manufactured, but legacy ARM-based PC hardware remains popular in
135 Europe. There is an ARM Linux project with a web page at
136 <http://www.arm.linux.org.uk/>.
137
138config ARM_HAS_SG_CHAIN
139 bool
140
141config ARM_DMA_USE_IOMMU
142 bool
143 select ARM_HAS_SG_CHAIN
144 select NEED_SG_DMA_LENGTH
145
146if ARM_DMA_USE_IOMMU
147
148config ARM_DMA_IOMMU_ALIGNMENT
149 int "Maximum PAGE_SIZE order of alignment for DMA IOMMU buffers"
150 range 4 9
151 default 8
152 help
153 DMA mapping framework by default aligns all buffers to the smallest
154 PAGE_SIZE order which is greater than or equal to the requested buffer
155 size. This works well for buffers up to a few hundreds kilobytes, but
156 for larger buffers it just a waste of address space. Drivers which has
157 relatively small addressing window (like 64Mib) might run out of
158 virtual space with just a few allocations.
159
160 With this parameter you can specify the maximum PAGE_SIZE order for
161 DMA IOMMU buffers. Larger buffers will be aligned only to this
162 specified order. The order is expressed as a power of two multiplied
163 by the PAGE_SIZE.
164
165endif
166
167config SYS_SUPPORTS_APM_EMULATION
168 bool
169
170config HAVE_TCM
171 bool
172 select GENERIC_ALLOCATOR
173
174config HAVE_PROC_CPU
175 bool
176
177config NO_IOPORT_MAP
178 bool
179
180config SBUS
181 bool
182
183config STACKTRACE_SUPPORT
184 bool
185 default y
186
187config LOCKDEP_SUPPORT
188 bool
189 default y
190
191config TRACE_IRQFLAGS_SUPPORT
192 bool
193 default !CPU_V7M
194
195config ARCH_HAS_ILOG2_U32
196 bool
197
198config ARCH_HAS_ILOG2_U64
199 bool
200
201config ARCH_HAS_BANDGAP
202 bool
203
204config FIX_EARLYCON_MEM
205 def_bool y if MMU
206
207config GENERIC_HWEIGHT
208 bool
209 default y
210
211config GENERIC_CALIBRATE_DELAY
212 bool
213 default y
214
215config ARCH_MAY_HAVE_PC_FDC
216 bool
217
218config ZONE_DMA
219 bool
220
221config ARCH_SUPPORTS_UPROBES
222 def_bool y
223
224config ARCH_HAS_DMA_SET_COHERENT_MASK
225 bool
226
227config GENERIC_ISA_DMA
228 bool
229
230config FIQ
231 bool
232
233config NEED_RET_TO_USER
234 bool
235
236config ARCH_MTD_XIP
237 bool
238
239config ARM_PATCH_PHYS_VIRT
240 bool "Patch physical to virtual translations at runtime" if EMBEDDED
241 default y
242 depends on !XIP_KERNEL && MMU
243 help
244 Patch phys-to-virt and virt-to-phys translation functions at
245 boot and module load time according to the position of the
246 kernel in system memory.
247
248 This can only be used with non-XIP MMU kernels where the base
249 of physical memory is at a 16MB boundary.
250
251 Only disable this option if you know that you do not require
252 this feature (eg, building a kernel for a single machine) and
253 you need to shrink the kernel to the minimal size.
254
255config NEED_MACH_IO_H
256 bool
257 help
258 Select this when mach/io.h is required to provide special
259 definitions for this platform. The need for mach/io.h should
260 be avoided when possible.
261
262config NEED_MACH_MEMORY_H
263 bool
264 help
265 Select this when mach/memory.h is required to provide special
266 definitions for this platform. The need for mach/memory.h should
267 be avoided when possible.
268
269config PHYS_OFFSET
270 hex "Physical address of main memory" if MMU
271 depends on !ARM_PATCH_PHYS_VIRT
272 default DRAM_BASE if !MMU
273 default 0x00000000 if ARCH_EBSA110 || \
274 ARCH_FOOTBRIDGE || \
275 ARCH_INTEGRATOR || \
276 ARCH_REALVIEW
277 default 0x10000000 if ARCH_OMAP1 || ARCH_RPC
278 default 0x20000000 if ARCH_S5PV210
279 default 0xc0000000 if ARCH_SA1100
280 help
281 Please provide the physical address corresponding to the
282 location of main memory in your system.
283
284config GENERIC_BUG
285 def_bool y
286 depends on BUG
287
288config PGTABLE_LEVELS
289 int
290 default 3 if ARM_LPAE
291 default 2
292
293menu "System Type"
294
295config MMU
296 bool "MMU-based Paged Memory Management Support"
297 default y
298 help
299 Select if you want MMU-based virtualised addressing space
300 support by paged memory management. If unsure, say 'Y'.
301
302config ARCH_MMAP_RND_BITS_MIN
303 default 8
304
305config ARCH_MMAP_RND_BITS_MAX
306 default 14 if PAGE_OFFSET=0x40000000
307 default 15 if PAGE_OFFSET=0x80000000
308 default 16
309
310#
311# The "ARM system type" choice list is ordered alphabetically by option
312# text. Please add new entries in the option alphabetic order.
313#
314choice
315 prompt "ARM system type"
316 default ARM_SINGLE_ARMV7M if !MMU
317 default ARCH_MULTIPLATFORM if MMU
318
319config ARCH_MULTIPLATFORM
320 bool "Allow multiple platforms to be selected"
321 depends on MMU
322 select ARM_HAS_SG_CHAIN
323 select ARM_PATCH_PHYS_VIRT
324 select AUTO_ZRELADDR
325 select TIMER_OF
326 select COMMON_CLK
327 select GENERIC_CLOCKEVENTS
328 select GENERIC_IRQ_MULTI_HANDLER
329 select HAVE_PCI
330 select PCI_DOMAINS_GENERIC if PCI
331 select SPARSE_IRQ
332 select USE_OF
333
334config ARM_SINGLE_ARMV7M
335 bool "ARMv7-M based platforms (Cortex-M0/M3/M4)"
336 depends on !MMU
337 select ARM_NVIC
338 select AUTO_ZRELADDR
339 select TIMER_OF
340 select COMMON_CLK
341 select CPU_V7M
342 select GENERIC_CLOCKEVENTS
343 select NO_IOPORT_MAP
344 select SPARSE_IRQ
345 select USE_OF
346
347config ARCH_EBSA110
348 bool "EBSA-110"
349 select ARCH_USES_GETTIMEOFFSET
350 select CPU_SA110
351 select ISA
352 select NEED_MACH_IO_H
353 select NEED_MACH_MEMORY_H
354 select NO_IOPORT_MAP
355 help
356 This is an evaluation board for the StrongARM processor available
357 from Digital. It has limited hardware on-board, including an
358 Ethernet interface, two PCMCIA sockets, two serial ports and a
359 parallel port.
360
361config ARCH_EP93XX
362 bool "EP93xx-based"
363 select ARCH_SPARSEMEM_ENABLE
364 select ARM_AMBA
365 imply ARM_PATCH_PHYS_VIRT
366 select ARM_VIC
367 select AUTO_ZRELADDR
368 select CLKDEV_LOOKUP
369 select CLKSRC_MMIO
370 select CPU_ARM920T
371 select GENERIC_CLOCKEVENTS
372 select GPIOLIB
373 help
374 This enables support for the Cirrus EP93xx series of CPUs.
375
376config ARCH_FOOTBRIDGE
377 bool "FootBridge"
378 select CPU_SA110
379 select FOOTBRIDGE
380 select GENERIC_CLOCKEVENTS
381 select HAVE_IDE
382 select NEED_MACH_IO_H if !MMU
383 select NEED_MACH_MEMORY_H
384 help
385 Support for systems based on the DC21285 companion chip
386 ("FootBridge"), such as the Simtec CATS and the Rebel NetWinder.
387
388config ARCH_IOP32X
389 bool "IOP32x-based"
390 depends on MMU
391 select CPU_XSCALE
392 select GPIO_IOP
393 select GPIOLIB
394 select NEED_RET_TO_USER
395 select FORCE_PCI
396 select PLAT_IOP
397 help
398 Support for Intel's 80219 and IOP32X (XScale) family of
399 processors.
400
401config ARCH_IXP4XX
402 bool "IXP4xx-based"
403 depends on MMU
404 select ARCH_HAS_DMA_SET_COHERENT_MASK
405 select ARCH_SUPPORTS_BIG_ENDIAN
406 select CPU_XSCALE
407 select DMABOUNCE if PCI
408 select GENERIC_CLOCKEVENTS
409 select GENERIC_IRQ_MULTI_HANDLER
410 select GPIO_IXP4XX
411 select GPIOLIB
412 select HAVE_PCI
413 select IXP4XX_IRQ
414 select IXP4XX_TIMER
415 select NEED_MACH_IO_H
416 select USB_EHCI_BIG_ENDIAN_DESC
417 select USB_EHCI_BIG_ENDIAN_MMIO
418 help
419 Support for Intel's IXP4XX (XScale) family of processors.
420
421config ARCH_DOVE
422 bool "Marvell Dove"
423 select CPU_PJ4
424 select GENERIC_CLOCKEVENTS
425 select GENERIC_IRQ_MULTI_HANDLER
426 select GPIOLIB
427 select HAVE_PCI
428 select MVEBU_MBUS
429 select PINCTRL
430 select PINCTRL_DOVE
431 select PLAT_ORION_LEGACY
432 select SPARSE_IRQ
433 select PM_GENERIC_DOMAINS if PM
434 help
435 Support for the Marvell Dove SoC 88AP510
436
437config ARCH_PXA
438 bool "PXA2xx/PXA3xx-based"
439 depends on MMU
440 select ARCH_MTD_XIP
441 select ARM_CPU_SUSPEND if PM
442 select AUTO_ZRELADDR
443 select COMMON_CLK
444 select CLKDEV_LOOKUP
445 select CLKSRC_PXA
446 select CLKSRC_MMIO
447 select TIMER_OF
448 select CPU_XSCALE if !CPU_XSC3
449 select GENERIC_CLOCKEVENTS
450 select GENERIC_IRQ_MULTI_HANDLER
451 select GPIO_PXA
452 select GPIOLIB
453 select HAVE_IDE
454 select IRQ_DOMAIN
455 select PLAT_PXA
456 select SPARSE_IRQ
457 help
458 Support for Intel/Marvell's PXA2xx/PXA3xx processor line.
459
460config ARCH_RPC
461 bool "RiscPC"
462 depends on MMU
463 select ARCH_ACORN
464 select ARCH_MAY_HAVE_PC_FDC
465 select ARCH_SPARSEMEM_ENABLE
466 select ARM_HAS_SG_CHAIN
467 select CPU_SA110
468 select FIQ
469 select HAVE_IDE
470 select HAVE_PATA_PLATFORM
471 select ISA_DMA_API
472 select NEED_MACH_IO_H
473 select NEED_MACH_MEMORY_H
474 select NO_IOPORT_MAP
475 help
476 On the Acorn Risc-PC, Linux can support the internal IDE disk and
477 CD-ROM interface, serial and parallel port, and the floppy drive.
478
479config ARCH_SA1100
480 bool "SA1100-based"
481 select ARCH_MTD_XIP
482 select ARCH_SPARSEMEM_ENABLE
483 select CLKDEV_LOOKUP
484 select CLKSRC_MMIO
485 select CLKSRC_PXA
486 select TIMER_OF if OF
487 select COMMON_CLK
488 select CPU_FREQ
489 select CPU_SA1100
490 select GENERIC_CLOCKEVENTS
491 select GENERIC_IRQ_MULTI_HANDLER
492 select GPIOLIB
493 select HAVE_IDE
494 select IRQ_DOMAIN
495 select ISA
496 select NEED_MACH_MEMORY_H
497 select SPARSE_IRQ
498 help
499 Support for StrongARM 11x0 based boards.
500
501config ARCH_S3C24XX
502 bool "Samsung S3C24XX SoCs"
503 select ATAGS
504 select CLKDEV_LOOKUP
505 select CLKSRC_SAMSUNG_PWM
506 select GENERIC_CLOCKEVENTS
507 select GPIO_SAMSUNG
508 select GPIOLIB
509 select GENERIC_IRQ_MULTI_HANDLER
510 select HAVE_S3C2410_I2C if I2C
511 select HAVE_S3C2410_WATCHDOG if WATCHDOG
512 select HAVE_S3C_RTC if RTC_CLASS
513 select NEED_MACH_IO_H
514 select S3C2410_WATCHDOG
515 select SAMSUNG_ATAGS
516 select USE_OF
517 select WATCHDOG
518 help
519 Samsung S3C2410, S3C2412, S3C2413, S3C2416, S3C2440, S3C2442, S3C2443
520 and S3C2450 SoCs based systems, such as the Simtec Electronics BAST
521 (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or the
522 Samsung SMDK2410 development board (and derivatives).
523
524config ARCH_OMAP1
525 bool "TI OMAP1"
526 depends on MMU
527 select ARCH_OMAP
528 select CLKDEV_LOOKUP
529 select CLKSRC_MMIO
530 select GENERIC_CLOCKEVENTS
531 select GENERIC_IRQ_CHIP
532 select GENERIC_IRQ_MULTI_HANDLER
533 select GPIOLIB
534 select HAVE_IDE
535 select IRQ_DOMAIN
536 select NEED_MACH_IO_H if PCCARD
537 select NEED_MACH_MEMORY_H
538 select SPARSE_IRQ
539 help
540 Support for older TI OMAP1 (omap7xx, omap15xx or omap16xx)
541
542endchoice
543
544menu "Multiple platform selection"
545 depends on ARCH_MULTIPLATFORM
546
547comment "CPU Core family selection"
548
549config ARCH_MULTI_V4
550 bool "ARMv4 based platforms (FA526)"
551 depends on !ARCH_MULTI_V6_V7
552 select ARCH_MULTI_V4_V5
553 select CPU_FA526
554
555config ARCH_MULTI_V4T
556 bool "ARMv4T based platforms (ARM720T, ARM920T, ...)"
557 depends on !ARCH_MULTI_V6_V7
558 select ARCH_MULTI_V4_V5
559 select CPU_ARM920T if !(CPU_ARM7TDMI || CPU_ARM720T || \
560 CPU_ARM740T || CPU_ARM9TDMI || CPU_ARM922T || \
561 CPU_ARM925T || CPU_ARM940T)
562
563config ARCH_MULTI_V5
564 bool "ARMv5 based platforms (ARM926T, XSCALE, PJ1, ...)"
565 depends on !ARCH_MULTI_V6_V7
566 select ARCH_MULTI_V4_V5
567 select CPU_ARM926T if !(CPU_ARM946E || CPU_ARM1020 || \
568 CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || \
569 CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_FEROCEON)
570
571config ARCH_MULTI_V4_V5
572 bool
573
574config ARCH_MULTI_V6
575 bool "ARMv6 based platforms (ARM11)"
576 select ARCH_MULTI_V6_V7
577 select CPU_V6K
578
579config ARCH_MULTI_V7
580 bool "ARMv7 based platforms (Cortex-A, PJ4, Scorpion, Krait)"
581 default y
582 select ARCH_MULTI_V6_V7
583 select CPU_V7
584 select HAVE_SMP
585
586config ARCH_MULTI_V6_V7
587 bool
588 select MIGHT_HAVE_CACHE_L2X0
589
590config ARCH_MULTI_CPU_AUTO
591 def_bool !(ARCH_MULTI_V4 || ARCH_MULTI_V4T || ARCH_MULTI_V6_V7)
592 select ARCH_MULTI_V5
593
594endmenu
595
596config ARCH_VIRT
597 bool "Dummy Virtual Machine"
598 depends on ARCH_MULTI_V7
599 select ARM_AMBA
600 select ARM_GIC
601 select ARM_GIC_V2M if PCI
602 select ARM_GIC_V3
603 select ARM_GIC_V3_ITS if PCI
604 select ARM_PSCI
605 select HAVE_ARM_ARCH_TIMER
606 select ARCH_SUPPORTS_BIG_ENDIAN
607
608#
609# This is sorted alphabetically by mach-* pathname. However, plat-*
610# Kconfigs may be included either alphabetically (according to the
611# plat- suffix) or along side the corresponding mach-* source.
612#
613source "arch/arm/mach-actions/Kconfig"
614
615source "arch/arm/mach-alpine/Kconfig"
616
617source "arch/arm/mach-artpec/Kconfig"
618
619source "arch/arm/mach-asm9260/Kconfig"
620
621source "arch/arm/mach-aspeed/Kconfig"
622
623source "arch/arm/mach-at91/Kconfig"
624
625source "arch/arm/mach-axxia/Kconfig"
626
627source "arch/arm/mach-bcm/Kconfig"
628
629source "arch/arm/mach-berlin/Kconfig"
630
631source "arch/arm/mach-clps711x/Kconfig"
632
633source "arch/arm/mach-cns3xxx/Kconfig"
634
635source "arch/arm/mach-davinci/Kconfig"
636
637source "arch/arm/mach-digicolor/Kconfig"
638
639source "arch/arm/mach-dove/Kconfig"
640
641source "arch/arm/mach-ep93xx/Kconfig"
642
643source "arch/arm/mach-exynos/Kconfig"
644source "arch/arm/plat-samsung/Kconfig"
645
646source "arch/arm/mach-footbridge/Kconfig"
647
648source "arch/arm/mach-gemini/Kconfig"
649
650source "arch/arm/mach-highbank/Kconfig"
651
652source "arch/arm/mach-hisi/Kconfig"
653
654source "arch/arm/mach-imx/Kconfig"
655
656source "arch/arm/mach-integrator/Kconfig"
657
658source "arch/arm/mach-iop32x/Kconfig"
659
660source "arch/arm/mach-ixp4xx/Kconfig"
661
662source "arch/arm/mach-keystone/Kconfig"
663
664source "arch/arm/mach-lpc32xx/Kconfig"
665
666source "arch/arm/mach-mediatek/Kconfig"
667
668source "arch/arm/mach-meson/Kconfig"
669
670source "arch/arm/mach-milbeaut/Kconfig"
671
672source "arch/arm/mach-mmp/Kconfig"
673
674source "arch/arm/mach-moxart/Kconfig"
675
676source "arch/arm/mach-mv78xx0/Kconfig"
677
678source "arch/arm/mach-mvebu/Kconfig"
679
680source "arch/arm/mach-mxs/Kconfig"
681
682source "arch/arm/mach-nomadik/Kconfig"
683
684source "arch/arm/mach-npcm/Kconfig"
685
686source "arch/arm/mach-nspire/Kconfig"
687
688source "arch/arm/plat-omap/Kconfig"
689
690source "arch/arm/mach-omap1/Kconfig"
691
692source "arch/arm/mach-omap2/Kconfig"
693
694source "arch/arm/mach-orion5x/Kconfig"
695
696source "arch/arm/mach-oxnas/Kconfig"
697
698source "arch/arm/mach-picoxcell/Kconfig"
699
700source "arch/arm/mach-prima2/Kconfig"
701
702source "arch/arm/mach-pxa/Kconfig"
703source "arch/arm/plat-pxa/Kconfig"
704
705source "arch/arm/mach-qcom/Kconfig"
706
707source "arch/arm/mach-rda/Kconfig"
708
709source "arch/arm/mach-realview/Kconfig"
710
711source "arch/arm/mach-rockchip/Kconfig"
712
713source "arch/arm/mach-s3c24xx/Kconfig"
714
715source "arch/arm/mach-s3c64xx/Kconfig"
716
717source "arch/arm/mach-s5pv210/Kconfig"
718
719source "arch/arm/mach-sa1100/Kconfig"
720
721source "arch/arm/mach-shmobile/Kconfig"
722
723source "arch/arm/mach-socfpga/Kconfig"
724
725source "arch/arm/mach-spear/Kconfig"
726
727source "arch/arm/mach-sti/Kconfig"
728
729source "arch/arm/mach-stm32/Kconfig"
730
731source "arch/arm/mach-sunxi/Kconfig"
732
733source "arch/arm/mach-tango/Kconfig"
734
735source "arch/arm/mach-tegra/Kconfig"
736
737source "arch/arm/mach-u300/Kconfig"
738
739source "arch/arm/mach-uniphier/Kconfig"
740
741source "arch/arm/mach-ux500/Kconfig"
742
743source "arch/arm/mach-versatile/Kconfig"
744
745source "arch/arm/mach-vexpress/Kconfig"
746source "arch/arm/plat-versatile/Kconfig"
747
748source "arch/arm/mach-vt8500/Kconfig"
749
750source "arch/arm/mach-zx/Kconfig"
751
752source "arch/arm/mach-zynq/Kconfig"
753
754# ARMv7-M architecture
755config ARCH_EFM32
756 bool "Energy Micro efm32"
757 depends on ARM_SINGLE_ARMV7M
758 select GPIOLIB
759 help
760 Support for Energy Micro's (now Silicon Labs) efm32 Giant Gecko
761 processors.
762
763config ARCH_LPC18XX
764 bool "NXP LPC18xx/LPC43xx"
765 depends on ARM_SINGLE_ARMV7M
766 select ARCH_HAS_RESET_CONTROLLER
767 select ARM_AMBA
768 select CLKSRC_LPC32XX
769 select PINCTRL
770 help
771 Support for NXP's LPC18xx Cortex-M3 and LPC43xx Cortex-M4
772 high performance microcontrollers.
773
774config ARCH_MPS2
775 bool "ARM MPS2 platform"
776 depends on ARM_SINGLE_ARMV7M
777 select ARM_AMBA
778 select CLKSRC_MPS2
779 help
780 Support for Cortex-M Prototyping System (or V2M-MPS2) which comes
781 with a range of available cores like Cortex-M3/M4/M7.
782
783 Please, note that depends which Application Note is used memory map
784 for the platform may vary, so adjustment of RAM base might be needed.
785
786# Definitions to make life easier
787config ARCH_ACORN
788 bool
789
790config PLAT_IOP
791 bool
792 select GENERIC_CLOCKEVENTS
793
794config PLAT_ORION
795 bool
796 select CLKSRC_MMIO
797 select COMMON_CLK
798 select GENERIC_IRQ_CHIP
799 select IRQ_DOMAIN
800
801config PLAT_ORION_LEGACY
802 bool
803 select PLAT_ORION
804
805config PLAT_PXA
806 bool
807 default y
808
809config PLAT_VERSATILE
810 bool
811
812source "arch/arm/mm/Kconfig"
813
814config IWMMXT
815 bool "Enable iWMMXt support"
816 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B
817 default y if PXA27x || PXA3xx || CPU_PJ4 || CPU_PJ4B
818 help
819 Enable support for iWMMXt context switching at run time if
820 running on a CPU that supports it.
821
822if !MMU
823source "arch/arm/Kconfig-nommu"
824endif
825
826config PJ4B_ERRATA_4742
827 bool "PJ4B Errata 4742: IDLE Wake Up Commands can Cause the CPU Core to Cease Operation"
828 depends on CPU_PJ4B && MACH_ARMADA_370
829 default y
830 help
831 When coming out of either a Wait for Interrupt (WFI) or a Wait for
832 Event (WFE) IDLE states, a specific timing sensitivity exists between
833 the retiring WFI/WFE instructions and the newly issued subsequent
834 instructions. This sensitivity can result in a CPU hang scenario.
835 Workaround:
836 The software must insert either a Data Synchronization Barrier (DSB)
837 or Data Memory Barrier (DMB) command immediately after the WFI/WFE
838 instruction
839
840config ARM_ERRATA_326103
841 bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory"
842 depends on CPU_V6
843 help
844 Executing a SWP instruction to read-only memory does not set bit 11
845 of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to
846 treat the access as a read, preventing a COW from occurring and
847 causing the faulting task to livelock.
848
849config ARM_ERRATA_411920
850 bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
851 depends on CPU_V6 || CPU_V6K
852 help
853 Invalidation of the Instruction Cache operation can
854 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
855 It does not affect the MPCore. This option enables the ARM Ltd.
856 recommended workaround.
857
858config ARM_ERRATA_430973
859 bool "ARM errata: Stale prediction on replaced interworking branch"
860 depends on CPU_V7
861 help
862 This option enables the workaround for the 430973 Cortex-A8
863 r1p* erratum. If a code sequence containing an ARM/Thumb
864 interworking branch is replaced with another code sequence at the
865 same virtual address, whether due to self-modifying code or virtual
866 to physical address re-mapping, Cortex-A8 does not recover from the
867 stale interworking branch prediction. This results in Cortex-A8
868 executing the new code sequence in the incorrect ARM or Thumb state.
869 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
870 and also flushes the branch target cache at every context switch.
871 Note that setting specific bits in the ACTLR register may not be
872 available in non-secure mode.
873
874config ARM_ERRATA_458693
875 bool "ARM errata: Processor deadlock when a false hazard is created"
876 depends on CPU_V7
877 depends on !ARCH_MULTIPLATFORM
878 help
879 This option enables the workaround for the 458693 Cortex-A8 (r2p0)
880 erratum. For very specific sequences of memory operations, it is
881 possible for a hazard condition intended for a cache line to instead
882 be incorrectly associated with a different cache line. This false
883 hazard might then cause a processor deadlock. The workaround enables
884 the L1 caching of the NEON accesses and disables the PLD instruction
885 in the ACTLR register. Note that setting specific bits in the ACTLR
886 register may not be available in non-secure mode.
887
888config ARM_ERRATA_460075
889 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
890 depends on CPU_V7
891 depends on !ARCH_MULTIPLATFORM
892 help
893 This option enables the workaround for the 460075 Cortex-A8 (r2p0)
894 erratum. Any asynchronous access to the L2 cache may encounter a
895 situation in which recent store transactions to the L2 cache are lost
896 and overwritten with stale memory contents from external memory. The
897 workaround disables the write-allocate mode for the L2 cache via the
898 ACTLR register. Note that setting specific bits in the ACTLR register
899 may not be available in non-secure mode.
900
901config ARM_ERRATA_742230
902 bool "ARM errata: DMB operation may be faulty"
903 depends on CPU_V7 && SMP
904 depends on !ARCH_MULTIPLATFORM
905 help
906 This option enables the workaround for the 742230 Cortex-A9
907 (r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction
908 between two write operations may not ensure the correct visibility
909 ordering of the two writes. This workaround sets a specific bit in
910 the diagnostic register of the Cortex-A9 which causes the DMB
911 instruction to behave as a DSB, ensuring the correct behaviour of
912 the two writes.
913
914config ARM_ERRATA_742231
915 bool "ARM errata: Incorrect hazard handling in the SCU may lead to data corruption"
916 depends on CPU_V7 && SMP
917 depends on !ARCH_MULTIPLATFORM
918 help
919 This option enables the workaround for the 742231 Cortex-A9
920 (r2p0..r2p2) erratum. Under certain conditions, specific to the
921 Cortex-A9 MPCore micro-architecture, two CPUs working in SMP mode,
922 accessing some data located in the same cache line, may get corrupted
923 data due to bad handling of the address hazard when the line gets
924 replaced from one of the CPUs at the same time as another CPU is
925 accessing it. This workaround sets specific bits in the diagnostic
926 register of the Cortex-A9 which reduces the linefill issuing
927 capabilities of the processor.
928
929config ARM_ERRATA_643719
930 bool "ARM errata: LoUIS bit field in CLIDR register is incorrect"
931 depends on CPU_V7 && SMP
932 default y
933 help
934 This option enables the workaround for the 643719 Cortex-A9 (prior to
935 r1p0) erratum. On affected cores the LoUIS bit field of the CLIDR
936 register returns zero when it should return one. The workaround
937 corrects this value, ensuring cache maintenance operations which use
938 it behave as intended and avoiding data corruption.
939
940config ARM_ERRATA_720789
941 bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID"
942 depends on CPU_V7
943 help
944 This option enables the workaround for the 720789 Cortex-A9 (prior to
945 r2p0) erratum. A faulty ASID can be sent to the other CPUs for the
946 broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS.
947 As a consequence of this erratum, some TLB entries which should be
948 invalidated are not, resulting in an incoherency in the system page
949 tables. The workaround changes the TLB flushing routines to invalidate
950 entries regardless of the ASID.
951
952config ARM_ERRATA_743622
953 bool "ARM errata: Faulty hazard checking in the Store Buffer may lead to data corruption"
954 depends on CPU_V7
955 depends on !ARCH_MULTIPLATFORM
956 help
957 This option enables the workaround for the 743622 Cortex-A9
958 (r2p*) erratum. Under very rare conditions, a faulty
959 optimisation in the Cortex-A9 Store Buffer may lead to data
960 corruption. This workaround sets a specific bit in the diagnostic
961 register of the Cortex-A9 which disables the Store Buffer
962 optimisation, preventing the defect from occurring. This has no
963 visible impact on the overall performance or power consumption of the
964 processor.
965
966config ARM_ERRATA_751472
967 bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation"
968 depends on CPU_V7
969 depends on !ARCH_MULTIPLATFORM
970 help
971 This option enables the workaround for the 751472 Cortex-A9 (prior
972 to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the
973 completion of a following broadcasted operation if the second
974 operation is received by a CPU before the ICIALLUIS has completed,
975 potentially leading to corrupted entries in the cache or TLB.
976
977config ARM_ERRATA_754322
978 bool "ARM errata: possible faulty MMU translations following an ASID switch"
979 depends on CPU_V7
980 help
981 This option enables the workaround for the 754322 Cortex-A9 (r2p*,
982 r3p*) erratum. A speculative memory access may cause a page table walk
983 which starts prior to an ASID switch but completes afterwards. This
984 can populate the micro-TLB with a stale entry which may be hit with
985 the new ASID. This workaround places two dsb instructions in the mm
986 switching code so that no page table walks can cross the ASID switch.
987
988config ARM_ERRATA_754327
989 bool "ARM errata: no automatic Store Buffer drain"
990 depends on CPU_V7 && SMP
991 help
992 This option enables the workaround for the 754327 Cortex-A9 (prior to
993 r2p0) erratum. The Store Buffer does not have any automatic draining
994 mechanism and therefore a livelock may occur if an external agent
995 continuously polls a memory location waiting to observe an update.
996 This workaround defines cpu_relax() as smp_mb(), preventing correctly
997 written polling loops from denying visibility of updates to memory.
998
999config ARM_ERRATA_364296
1000 bool "ARM errata: Possible cache data corruption with hit-under-miss enabled"
1001 depends on CPU_V6
1002 help
1003 This options enables the workaround for the 364296 ARM1136
1004 r0p2 erratum (possible cache data corruption with
1005 hit-under-miss enabled). It sets the undocumented bit 31 in
1006 the auxiliary control register and the FI bit in the control
1007 register, thus disabling hit-under-miss without putting the
1008 processor into full low interrupt latency mode. ARM11MPCore
1009 is not affected.
1010
1011config ARM_ERRATA_764369
1012 bool "ARM errata: Data cache line maintenance operation by MVA may not succeed"
1013 depends on CPU_V7 && SMP
1014 help
1015 This option enables the workaround for erratum 764369
1016 affecting Cortex-A9 MPCore with two or more processors (all
1017 current revisions). Under certain timing circumstances, a data
1018 cache line maintenance operation by MVA targeting an Inner
1019 Shareable memory region may fail to proceed up to either the
1020 Point of Coherency or to the Point of Unification of the
1021 system. This workaround adds a DSB instruction before the
1022 relevant cache maintenance functions and sets a specific bit
1023 in the diagnostic control register of the SCU.
1024
1025config ARM_ERRATA_775420
1026 bool "ARM errata: A data cache maintenance operation which aborts, might lead to deadlock"
1027 depends on CPU_V7
1028 help
1029 This option enables the workaround for the 775420 Cortex-A9 (r2p2,
1030 r2p6,r2p8,r2p10,r3p0) erratum. In case a date cache maintenance
1031 operation aborts with MMU exception, it might cause the processor
1032 to deadlock. This workaround puts DSB before executing ISB if
1033 an abort may occur on cache maintenance.
1034
1035config ARM_ERRATA_798181
1036 bool "ARM errata: TLBI/DSB failure on Cortex-A15"
1037 depends on CPU_V7 && SMP
1038 help
1039 On Cortex-A15 (r0p0..r3p2) the TLBI*IS/DSB operations are not
1040 adequately shooting down all use of the old entries. This
1041 option enables the Linux kernel workaround for this erratum
1042 which sends an IPI to the CPUs that are running the same ASID
1043 as the one being invalidated.
1044
1045config ARM_ERRATA_773022
1046 bool "ARM errata: incorrect instructions may be executed from loop buffer"
1047 depends on CPU_V7
1048 help
1049 This option enables the workaround for the 773022 Cortex-A15
1050 (up to r0p4) erratum. In certain rare sequences of code, the
1051 loop buffer may deliver incorrect instructions. This
1052 workaround disables the loop buffer to avoid the erratum.
1053
1054config ARM_ERRATA_818325_852422
1055 bool "ARM errata: A12: some seqs of opposed cond code instrs => deadlock or corruption"
1056 depends on CPU_V7
1057 help
1058 This option enables the workaround for:
1059 - Cortex-A12 818325: Execution of an UNPREDICTABLE STR or STM
1060 instruction might deadlock. Fixed in r0p1.
1061 - Cortex-A12 852422: Execution of a sequence of instructions might
1062 lead to either a data corruption or a CPU deadlock. Not fixed in
1063 any Cortex-A12 cores yet.
1064 This workaround for all both errata involves setting bit[12] of the
1065 Feature Register. This bit disables an optimisation applied to a
1066 sequence of 2 instructions that use opposing condition codes.
1067
1068config ARM_ERRATA_821420
1069 bool "ARM errata: A12: sequence of VMOV to core registers might lead to a dead lock"
1070 depends on CPU_V7
1071 help
1072 This option enables the workaround for the 821420 Cortex-A12
1073 (all revs) erratum. In very rare timing conditions, a sequence
1074 of VMOV to Core registers instructions, for which the second
1075 one is in the shadow of a branch or abort, can lead to a
1076 deadlock when the VMOV instructions are issued out-of-order.
1077
1078config ARM_ERRATA_825619
1079 bool "ARM errata: A12: DMB NSHST/ISHST mixed ... might cause deadlock"
1080 depends on CPU_V7
1081 help
1082 This option enables the workaround for the 825619 Cortex-A12
1083 (all revs) erratum. Within rare timing constraints, executing a
1084 DMB NSHST or DMB ISHST instruction followed by a mix of Cacheable
1085 and Device/Strongly-Ordered loads and stores might cause deadlock
1086
1087config ARM_ERRATA_857271
1088 bool "ARM errata: A12: CPU might deadlock under some very rare internal conditions"
1089 depends on CPU_V7
1090 help
1091 This option enables the workaround for the 857271 Cortex-A12
1092 (all revs) erratum. Under very rare timing conditions, the CPU might
1093 hang. The workaround is expected to have a < 1% performance impact.
1094
1095config ARM_ERRATA_852421
1096 bool "ARM errata: A17: DMB ST might fail to create order between stores"
1097 depends on CPU_V7
1098 help
1099 This option enables the workaround for the 852421 Cortex-A17
1100 (r1p0, r1p1, r1p2) erratum. Under very rare timing conditions,
1101 execution of a DMB ST instruction might fail to properly order
1102 stores from GroupA and stores from GroupB.
1103
1104config ARM_ERRATA_852423
1105 bool "ARM errata: A17: some seqs of opposed cond code instrs => deadlock or corruption"
1106 depends on CPU_V7
1107 help
1108 This option enables the workaround for:
1109 - Cortex-A17 852423: Execution of a sequence of instructions might
1110 lead to either a data corruption or a CPU deadlock. Not fixed in
1111 any Cortex-A17 cores yet.
1112 This is identical to Cortex-A12 erratum 852422. It is a separate
1113 config option from the A12 erratum due to the way errata are checked
1114 for and handled.
1115
1116config ARM_ERRATA_857272
1117 bool "ARM errata: A17: CPU might deadlock under some very rare internal conditions"
1118 depends on CPU_V7
1119 help
1120 This option enables the workaround for the 857272 Cortex-A17 erratum.
1121 This erratum is not known to be fixed in any A17 revision.
1122 This is identical to Cortex-A12 erratum 857271. It is a separate
1123 config option from the A12 erratum due to the way errata are checked
1124 for and handled.
1125
1126endmenu
1127
1128source "arch/arm/common/Kconfig"
1129
1130menu "Bus support"
1131
1132config ISA
1133 bool
1134 help
1135 Find out whether you have ISA slots on your motherboard. ISA is the
1136 name of a bus system, i.e. the way the CPU talks to the other stuff
1137 inside your box. Other bus systems are PCI, EISA, MicroChannel
1138 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1139 newer boards don't support it. If you have ISA, say Y, otherwise N.
1140
1141# Select ISA DMA controller support
1142config ISA_DMA
1143 bool
1144 select ISA_DMA_API
1145
1146# Select ISA DMA interface
1147config ISA_DMA_API
1148 bool
1149
1150config PCI_NANOENGINE
1151 bool "BSE nanoEngine PCI support"
1152 depends on SA1100_NANOENGINE
1153 help
1154 Enable PCI on the BSE nanoEngine board.
1155
1156config PCI_HOST_ITE8152
1157 bool
1158 depends on PCI && MACH_ARMCORE
1159 default y
1160 select DMABOUNCE
1161
1162config ARM_ERRATA_814220
1163 bool "ARM errata: Cache maintenance by set/way operations can execute out of order"
1164 depends on CPU_V7
1165 help
1166 The v7 ARM states that all cache and branch predictor maintenance
1167 operations that do not specify an address execute, relative to
1168 each other, in program order.
1169 However, because of this erratum, an L2 set/way cache maintenance
1170 operation can overtake an L1 set/way cache maintenance operation.
1171 This ERRATA only affected the Cortex-A7 and present in r0p2, r0p3,
1172 r0p4, r0p5.
1173
1174endmenu
1175
1176menu "Kernel Features"
1177
1178config HAVE_SMP
1179 bool
1180 help
1181 This option should be selected by machines which have an SMP-
1182 capable CPU.
1183
1184 The only effect of this option is to make the SMP-related
1185 options available to the user for configuration.
1186
1187config SMP
1188 bool "Symmetric Multi-Processing"
1189 depends on CPU_V6K || CPU_V7
1190 depends on GENERIC_CLOCKEVENTS
1191 depends on HAVE_SMP
1192 depends on MMU || ARM_MPU
1193 select IRQ_WORK
1194 help
1195 This enables support for systems with more than one CPU. If you have
1196 a system with only one CPU, say N. If you have a system with more
1197 than one CPU, say Y.
1198
1199 If you say N here, the kernel will run on uni- and multiprocessor
1200 machines, but will use only one CPU of a multiprocessor machine. If
1201 you say Y here, the kernel will run on many, but not all,
1202 uniprocessor machines. On a uniprocessor machine, the kernel
1203 will run faster if you say N here.
1204
1205 See also <file:Documentation/x86/i386/IO-APIC.rst>,
1206 <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at
1207 <http://tldp.org/HOWTO/SMP-HOWTO.html>.
1208
1209 If you don't know what to do here, say N.
1210
1211config SMP_ON_UP
1212 bool "Allow booting SMP kernel on uniprocessor systems"
1213 depends on SMP && !XIP_KERNEL && MMU
1214 default y
1215 help
1216 SMP kernels contain instructions which fail on non-SMP processors.
1217 Enabling this option allows the kernel to modify itself to make
1218 these instructions safe. Disabling it allows about 1K of space
1219 savings.
1220
1221 If you don't know what to do here, say Y.
1222
1223config ARM_CPU_TOPOLOGY
1224 bool "Support cpu topology definition"
1225 depends on SMP && CPU_V7
1226 default y
1227 help
1228 Support ARM cpu topology definition. The MPIDR register defines
1229 affinity between processors which is then used to describe the cpu
1230 topology of an ARM System.
1231
1232config SCHED_MC
1233 bool "Multi-core scheduler support"
1234 depends on ARM_CPU_TOPOLOGY
1235 help
1236 Multi-core scheduler support improves the CPU scheduler's decision
1237 making when dealing with multi-core CPU chips at a cost of slightly
1238 increased overhead in some places. If unsure say N here.
1239
1240config SCHED_SMT
1241 bool "SMT scheduler support"
1242 depends on ARM_CPU_TOPOLOGY
1243 help
1244 Improves the CPU scheduler's decision making when dealing with
1245 MultiThreading at a cost of slightly increased overhead in some
1246 places. If unsure say N here.
1247
1248config HAVE_ARM_SCU
1249 bool
1250 help
1251 This option enables support for the ARM snoop control unit
1252
1253config HAVE_ARM_ARCH_TIMER
1254 bool "Architected timer support"
1255 depends on CPU_V7
1256 select ARM_ARCH_TIMER
1257 select GENERIC_CLOCKEVENTS
1258 select GENERIC_GETTIMEOFDAY
1259 help
1260 This option enables support for the ARM architected timer
1261
1262config HAVE_ARM_TWD
1263 bool
1264 help
1265 This options enables support for the ARM timer and watchdog unit
1266
1267config MCPM
1268 bool "Multi-Cluster Power Management"
1269 depends on CPU_V7 && SMP
1270 help
1271 This option provides the common power management infrastructure
1272 for (multi-)cluster based systems, such as big.LITTLE based
1273 systems.
1274
1275config MCPM_QUAD_CLUSTER
1276 bool
1277 depends on MCPM
1278 help
1279 To avoid wasting resources unnecessarily, MCPM only supports up
1280 to 2 clusters by default.
1281 Platforms with 3 or 4 clusters that use MCPM must select this
1282 option to allow the additional clusters to be managed.
1283
1284config BIG_LITTLE
1285 bool "big.LITTLE support (Experimental)"
1286 depends on CPU_V7 && SMP
1287 select MCPM
1288 help
1289 This option enables support selections for the big.LITTLE
1290 system architecture.
1291
1292config BL_SWITCHER
1293 bool "big.LITTLE switcher support"
1294 depends on BIG_LITTLE && MCPM && HOTPLUG_CPU && ARM_GIC
1295 select CPU_PM
1296 help
1297 The big.LITTLE "switcher" provides the core functionality to
1298 transparently handle transition between a cluster of A15's
1299 and a cluster of A7's in a big.LITTLE system.
1300
1301config BL_SWITCHER_DUMMY_IF
1302 tristate "Simple big.LITTLE switcher user interface"
1303 depends on BL_SWITCHER && DEBUG_KERNEL
1304 help
1305 This is a simple and dummy char dev interface to control
1306 the big.LITTLE switcher core code. It is meant for
1307 debugging purposes only.
1308
1309choice
1310 prompt "Memory split"
1311 depends on MMU
1312 default VMSPLIT_3G
1313 help
1314 Select the desired split between kernel and user memory.
1315
1316 If you are not absolutely sure what you are doing, leave this
1317 option alone!
1318
1319 config VMSPLIT_3G
1320 bool "3G/1G user/kernel split"
1321 config VMSPLIT_3G_OPT
1322 depends on !ARM_LPAE
1323 bool "3G/1G user/kernel split (for full 1G low memory)"
1324 config VMSPLIT_2G
1325 bool "2G/2G user/kernel split"
1326 config VMSPLIT_1G
1327 bool "1G/3G user/kernel split"
1328endchoice
1329
1330config PAGE_OFFSET
1331 hex
1332 default PHYS_OFFSET if !MMU
1333 default 0x40000000 if VMSPLIT_1G
1334 default 0x80000000 if VMSPLIT_2G
1335 default 0xB0000000 if VMSPLIT_3G_OPT
1336 default 0xC0000000
1337
1338config PXA_MIPSRAM
1339 bool "Enable MIPSRAM monitoring support"
1340 help
1341 Enable MIPS RAM monitoring for process switching implemented in
1342 the scheduler
1343
1344config PXA_MIPSRAM_TRACK_TASKLETS_FUNCTIONS
1345 bool "Tracking tasklets function handlers and log into MIPSRAM's buffer"
1346 depends on PXA_MIPSRAM
1347 help
1348 Enable MIPS RAM monitoring of tasklets function handlers. use
1349 System.map or kallsyms to see functions name
1350
1351config PXA_RAMDUMP
1352 bool "RAMDUMP debug capability"
1353 help
1354 RAMDUMP saves the information about CPU and SoC state and
1355 enables offline debug based on system RAM image (dump).
1356 Can be used indepentently, or with KEXEC.
1357 A memory map anchor structure RDC is used to store part
1358 of the error information, and provide references to
1359 extended information, where both can be located by an
1360 offline parser without kernel symbol table use.
1361
1362config RAMDUMP_FIXED_PHYS_OFFSET
1363 hex "Fixed physical offset address for ramdump"
1364 default 0x00478000
1365
1366config NR_CPUS
1367 int "Maximum number of CPUs (2-32)"
1368 range 2 32
1369 depends on SMP
1370 default "4"
1371
1372config HOTPLUG_CPU
1373 bool "Support for hot-pluggable CPUs"
1374 depends on SMP
1375 select GENERIC_IRQ_MIGRATION
1376 help
1377 Say Y here to experiment with turning CPUs off and on. CPUs
1378 can be controlled through /sys/devices/system/cpu.
1379
1380config ARM_PSCI
1381 bool "Support for the ARM Power State Coordination Interface (PSCI)"
1382 depends on HAVE_ARM_SMCCC
1383 select ARM_PSCI_FW
1384 help
1385 Say Y here if you want Linux to communicate with system firmware
1386 implementing the PSCI specification for CPU-centric power
1387 management operations described in ARM document number ARM DEN
1388 0022A ("Power State Coordination Interface System Software on
1389 ARM processors").
1390
1391# The GPIO number here must be sorted by descending number. In case of
1392# a multiplatform kernel, we just want the highest value required by the
1393# selected platforms.
1394config ARCH_NR_GPIO
1395 int
1396 default 2048 if ARCH_SOCFPGA
1397 default 1024 if ARCH_BRCMSTB || ARCH_RENESAS || ARCH_TEGRA || \
1398 ARCH_ZYNQ
1399 default 512 if ARCH_EXYNOS || ARCH_KEYSTONE || SOC_OMAP5 || \
1400 SOC_DRA7XX || ARCH_S3C24XX || ARCH_S3C64XX || ARCH_S5PV210
1401 default 416 if ARCH_SUNXI
1402 default 392 if ARCH_U8500
1403 default 352 if ARCH_VT8500
1404 default 288 if ARCH_ROCKCHIP
1405 default 264 if MACH_H4700
1406 default 128 if ARCH_MMP
1407 default 0
1408 help
1409 Maximum number of GPIOs in the system.
1410
1411 If unsure, leave the default value.
1412
1413config HZ_FIXED
1414 int
1415 default 200 if ARCH_EBSA110
1416 default 128 if SOC_AT91RM9200
1417 default 0
1418
1419choice
1420 depends on HZ_FIXED = 0
1421 prompt "Timer frequency"
1422
1423config HZ_100
1424 bool "100 Hz"
1425
1426config HZ_200
1427 bool "200 Hz"
1428
1429config HZ_250
1430 bool "250 Hz"
1431
1432config HZ_300
1433 bool "300 Hz"
1434
1435config HZ_500
1436 bool "500 Hz"
1437
1438config HZ_1000
1439 bool "1000 Hz"
1440
1441endchoice
1442
1443config HZ
1444 int
1445 default HZ_FIXED if HZ_FIXED != 0
1446 default 100 if HZ_100
1447 default 200 if HZ_200
1448 default 250 if HZ_250
1449 default 300 if HZ_300
1450 default 500 if HZ_500
1451 default 1000
1452
1453config SCHED_HRTICK
1454 def_bool HIGH_RES_TIMERS
1455
1456config THUMB2_KERNEL
1457 bool "Compile the kernel in Thumb-2 mode" if !CPU_THUMBONLY
1458 depends on (CPU_V7 || CPU_V7M) && !CPU_V6 && !CPU_V6K
1459 default y if CPU_THUMBONLY
1460 select ARM_UNWIND
1461 help
1462 By enabling this option, the kernel will be compiled in
1463 Thumb-2 mode.
1464
1465 If unsure, say N.
1466
1467config THUMB2_AVOID_R_ARM_THM_JUMP11
1468 bool "Work around buggy Thumb-2 short branch relocations in gas"
1469 depends on THUMB2_KERNEL && MODULES
1470 default y
1471 help
1472 Various binutils versions can resolve Thumb-2 branches to
1473 locally-defined, preemptible global symbols as short-range "b.n"
1474 branch instructions.
1475
1476 This is a problem, because there's no guarantee the final
1477 destination of the symbol, or any candidate locations for a
1478 trampoline, are within range of the branch. For this reason, the
1479 kernel does not support fixing up the R_ARM_THM_JUMP11 (102)
1480 relocation in modules at all, and it makes little sense to add
1481 support.
1482
1483 The symptom is that the kernel fails with an "unsupported
1484 relocation" error when loading some modules.
1485
1486 Until fixed tools are available, passing
1487 -fno-optimize-sibling-calls to gcc should prevent gcc generating
1488 code which hits this problem, at the cost of a bit of extra runtime
1489 stack usage in some cases.
1490
1491 The problem is described in more detail at:
1492 https://bugs.launchpad.net/binutils-linaro/+bug/725126
1493
1494 Only Thumb-2 kernels are affected.
1495
1496 Unless you are sure your tools don't have this problem, say Y.
1497
1498config ARM_PATCH_IDIV
1499 bool "Runtime patch udiv/sdiv instructions into __aeabi_{u}idiv()"
1500 depends on CPU_32v7 && !XIP_KERNEL
1501 default y
1502 help
1503 The ARM compiler inserts calls to __aeabi_idiv() and
1504 __aeabi_uidiv() when it needs to perform division on signed
1505 and unsigned integers. Some v7 CPUs have support for the sdiv
1506 and udiv instructions that can be used to implement those
1507 functions.
1508
1509 Enabling this option allows the kernel to modify itself to
1510 replace the first two instructions of these library functions
1511 with the sdiv or udiv plus "bx lr" instructions when the CPU
1512 it is running on supports them. Typically this will be faster
1513 and less power intensive than running the original library
1514 code to do integer division.
1515
1516config AEABI
1517 bool "Use the ARM EABI to compile the kernel" if !CPU_V7 && \
1518 !CPU_V7M && !CPU_V6 && !CPU_V6K && !CC_IS_CLANG
1519 default CPU_V7 || CPU_V7M || CPU_V6 || CPU_V6K || CC_IS_CLANG
1520 help
1521 This option allows for the kernel to be compiled using the latest
1522 ARM ABI (aka EABI). This is only useful if you are using a user
1523 space environment that is also compiled with EABI.
1524
1525 Since there are major incompatibilities between the legacy ABI and
1526 EABI, especially with regard to structure member alignment, this
1527 option also changes the kernel syscall calling convention to
1528 disambiguate both ABIs and allow for backward compatibility support
1529 (selected with CONFIG_OABI_COMPAT).
1530
1531 To use this you need GCC version 4.0.0 or later.
1532
1533config OABI_COMPAT
1534 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1535 depends on AEABI && !THUMB2_KERNEL
1536 help
1537 This option preserves the old syscall interface along with the
1538 new (ARM EABI) one. It also provides a compatibility layer to
1539 intercept syscalls that have structure arguments which layout
1540 in memory differs between the legacy ABI and the new ARM EABI
1541 (only for non "thumb" binaries). This option adds a tiny
1542 overhead to all syscalls and produces a slightly larger kernel.
1543
1544 The seccomp filter system will not be available when this is
1545 selected, since there is no way yet to sensibly distinguish
1546 between calling conventions during filtering.
1547
1548 If you know you'll be using only pure EABI user space then you
1549 can say N here. If this option is not selected and you attempt
1550 to execute a legacy ABI binary then the result will be
1551 UNPREDICTABLE (in fact it can be predicted that it won't work
1552 at all). If in doubt say N.
1553
1554config ARCH_SPARSEMEM_ENABLE
1555 bool
1556
1557config ARCH_SPARSEMEM_DEFAULT
1558 def_bool ARCH_SPARSEMEM_ENABLE
1559
1560config HAVE_ARCH_PFN_VALID
1561 def_bool y
1562
1563config HIGHMEM
1564 bool "High Memory Support"
1565 depends on MMU
1566 help
1567 The address space of ARM processors is only 4 Gigabytes large
1568 and it has to accommodate user address space, kernel address
1569 space as well as some memory mapped IO. That means that, if you
1570 have a large amount of physical memory and/or IO, not all of the
1571 memory can be "permanently mapped" by the kernel. The physical
1572 memory that is not permanently mapped is called "high memory".
1573
1574 Depending on the selected kernel/user memory split, minimum
1575 vmalloc space and actual amount of RAM, you may not need this
1576 option which should result in a slightly faster kernel.
1577
1578 If unsure, say n.
1579
1580config HIGHPTE
1581 bool "Allocate 2nd-level pagetables from highmem" if EXPERT
1582 depends on HIGHMEM
1583 default y
1584 help
1585 The VM uses one page of physical memory for each page table.
1586 For systems with a lot of processes, this can use a lot of
1587 precious low memory, eventually leading to low memory being
1588 consumed by page tables. Setting this option will allow
1589 user-space 2nd level page tables to reside in high memory.
1590
1591config CPU_SW_DOMAIN_PAN
1592 bool "Enable use of CPU domains to implement privileged no-access"
1593 depends on MMU && !ARM_LPAE
1594 default y
1595 help
1596 Increase kernel security by ensuring that normal kernel accesses
1597 are unable to access userspace addresses. This can help prevent
1598 use-after-free bugs becoming an exploitable privilege escalation
1599 by ensuring that magic values (such as LIST_POISON) will always
1600 fault when dereferenced.
1601
1602 CPUs with low-vector mappings use a best-efforts implementation.
1603 Their lower 1MB needs to remain accessible for the vectors, but
1604 the remainder of userspace will become appropriately inaccessible.
1605
1606config HW_PERF_EVENTS
1607 def_bool y
1608 depends on ARM_PMU
1609
1610config SYS_SUPPORTS_HUGETLBFS
1611 def_bool y
1612 depends on ARM_LPAE
1613
1614config HAVE_ARCH_TRANSPARENT_HUGEPAGE
1615 def_bool y
1616 depends on ARM_LPAE
1617
1618config ARCH_WANT_GENERAL_HUGETLB
1619 def_bool y
1620
1621config ARM_MODULE_PLTS
1622 bool "Use PLTs to allow module memory to spill over into vmalloc area"
1623 depends on MODULES
1624 default y
1625 help
1626 Allocate PLTs when loading modules so that jumps and calls whose
1627 targets are too far away for their relative offsets to be encoded
1628 in the instructions themselves can be bounced via veneers in the
1629 module's PLT. This allows modules to be allocated in the generic
1630 vmalloc area after the dedicated module memory area has been
1631 exhausted. The modules will use slightly more memory, but after
1632 rounding up to page size, the actual memory footprint is usually
1633 the same.
1634
1635 Disabling this is usually safe for small single-platform
1636 configurations. If unsure, say y.
1637
1638config FORCE_MAX_ZONEORDER
1639 int "Maximum zone order"
1640 default "12" if SOC_AM33XX
1641 default "9" if SA1111 || ARCH_EFM32
1642 default "11"
1643 help
1644 The kernel memory allocator divides physically contiguous memory
1645 blocks into "zones", where each zone is a power of two number of
1646 pages. This option selects the largest power of two that the kernel
1647 keeps in the memory allocator. If you need to allocate very large
1648 blocks of physically contiguous memory, then you may need to
1649 increase this value.
1650
1651 This config option is actually maximum order plus one. For example,
1652 a value of 11 means that the largest free memory block is 2^10 pages.
1653
1654config ALIGNMENT_TRAP
1655 bool
1656 depends on CPU_CP15_MMU
1657 default y if !ARCH_EBSA110
1658 select HAVE_PROC_CPU if PROC_FS
1659 help
1660 ARM processors cannot fetch/store information which is not
1661 naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1662 address divisible by 4. On 32-bit ARM processors, these non-aligned
1663 fetch/store instructions will be emulated in software if you say
1664 here, which has a severe performance impact. This is necessary for
1665 correct operation of some network protocols. With an IP-only
1666 configuration it is safe to say N, otherwise say Y.
1667
1668config UACCESS_WITH_MEMCPY
1669 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user()"
1670 depends on MMU
1671 default y if CPU_FEROCEON
1672 help
1673 Implement faster copy_to_user and clear_user methods for CPU
1674 cores where a 8-word STM instruction give significantly higher
1675 memory write throughput than a sequence of individual 32bit stores.
1676
1677 A possible side effect is a slight increase in scheduling latency
1678 between threads sharing the same address space if they invoke
1679 such copy operations with large buffers.
1680
1681 However, if the CPU data cache is using a write-allocate mode,
1682 this option is unlikely to provide any performance gain.
1683
1684config SECCOMP
1685 bool
1686 prompt "Enable seccomp to safely compute untrusted bytecode"
1687 ---help---
1688 This kernel feature is useful for number crunching applications
1689 that may need to compute untrusted bytecode during their
1690 execution. By using pipes or other transports made available to
1691 the process as file descriptors supporting the read/write
1692 syscalls, it's possible to isolate those applications in
1693 their own address space using seccomp. Once seccomp is
1694 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1695 and the task is only allowed to execute a few safe syscalls
1696 defined by each seccomp mode.
1697
1698config PARAVIRT
1699 bool "Enable paravirtualization code"
1700 help
1701 This changes the kernel so it can modify itself when it is run
1702 under a hypervisor, potentially improving performance significantly
1703 over full virtualization.
1704
1705config PARAVIRT_TIME_ACCOUNTING
1706 bool "Paravirtual steal time accounting"
1707 select PARAVIRT
1708 help
1709 Select this option to enable fine granularity task steal time
1710 accounting. Time spent executing other tasks in parallel with
1711 the current vCPU is discounted from the vCPU power. To account for
1712 that, there can be a small performance impact.
1713
1714 If in doubt, say N here.
1715
1716config XEN_DOM0
1717 def_bool y
1718 depends on XEN
1719
1720config XEN
1721 bool "Xen guest support on ARM"
1722 depends on ARM && AEABI && OF
1723 depends on CPU_V7 && !CPU_V6
1724 depends on !GENERIC_ATOMIC64
1725 depends on MMU
1726 select ARCH_DMA_ADDR_T_64BIT
1727 select ARM_PSCI
1728 select SWIOTLB
1729 select SWIOTLB_XEN
1730 select PARAVIRT
1731 help
1732 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
1733
1734config STACKPROTECTOR_PER_TASK
1735 bool "Use a unique stack canary value for each task"
1736 depends on GCC_PLUGINS && STACKPROTECTOR && SMP && !XIP_DEFLATED_DATA
1737 select GCC_PLUGIN_ARM_SSP_PER_TASK
1738 default y
1739 help
1740 Due to the fact that GCC uses an ordinary symbol reference from
1741 which to load the value of the stack canary, this value can only
1742 change at reboot time on SMP systems, and all tasks running in the
1743 kernel's address space are forced to use the same canary value for
1744 the entire duration that the system is up.
1745
1746 Enable this option to switch to a different method that uses a
1747 different canary value for each task.
1748
1749endmenu
1750
1751menu "Boot options"
1752
1753config USE_OF
1754 bool "Flattened Device Tree support"
1755 select IRQ_DOMAIN
1756 select OF
1757 help
1758 Include support for flattened device tree machine descriptions.
1759
1760config ATAGS
1761 bool "Support for the traditional ATAGS boot data passing" if USE_OF
1762 default y
1763 help
1764 This is the traditional way of passing data to the kernel at boot
1765 time. If you are solely relying on the flattened device tree (or
1766 the ARM_ATAG_DTB_COMPAT option) then you may unselect this option
1767 to remove ATAGS support from your kernel binary. If unsure,
1768 leave this to y.
1769
1770config DEPRECATED_PARAM_STRUCT
1771 bool "Provide old way to pass kernel parameters"
1772 depends on ATAGS
1773 help
1774 This was deprecated in 2001 and announced to live on for 5 years.
1775 Some old boot loaders still use this way.
1776
1777# Compressed boot loader in ROM. Yes, we really want to ask about
1778# TEXT and BSS so we preserve their values in the config files.
1779config ZBOOT_ROM_TEXT
1780 hex "Compressed ROM boot loader base address"
1781 default "0"
1782 help
1783 The physical address at which the ROM-able zImage is to be
1784 placed in the target. Platforms which normally make use of
1785 ROM-able zImage formats normally set this to a suitable
1786 value in their defconfig file.
1787
1788 If ZBOOT_ROM is not enabled, this has no effect.
1789
1790config ZBOOT_ROM_BSS
1791 hex "Compressed ROM boot loader BSS address"
1792 default "0"
1793 help
1794 The base address of an area of read/write memory in the target
1795 for the ROM-able zImage which must be available while the
1796 decompressor is running. It must be large enough to hold the
1797 entire decompressed kernel plus an additional 128 KiB.
1798 Platforms which normally make use of ROM-able zImage formats
1799 normally set this to a suitable value in their defconfig file.
1800
1801 If ZBOOT_ROM is not enabled, this has no effect.
1802
1803config ZBOOT_ROM
1804 bool "Compressed boot loader in ROM/flash"
1805 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1806 depends on !ARM_APPENDED_DTB && !XIP_KERNEL && !AUTO_ZRELADDR
1807 help
1808 Say Y here if you intend to execute your compressed kernel image
1809 (zImage) directly from ROM or flash. If unsure, say N.
1810
1811config ARM_APPENDED_DTB
1812 bool "Use appended device tree blob to zImage (EXPERIMENTAL)"
1813 depends on OF
1814 help
1815 With this option, the boot code will look for a device tree binary
1816 (DTB) appended to zImage
1817 (e.g. cat zImage <filename>.dtb > zImage_w_dtb).
1818
1819 This is meant as a backward compatibility convenience for those
1820 systems with a bootloader that can't be upgraded to accommodate
1821 the documented boot protocol using a device tree.
1822
1823 Beware that there is very little in terms of protection against
1824 this option being confused by leftover garbage in memory that might
1825 look like a DTB header after a reboot if no actual DTB is appended
1826 to zImage. Do not leave this option active in a production kernel
1827 if you don't intend to always append a DTB. Proper passing of the
1828 location into r2 of a bootloader provided DTB is always preferable
1829 to this option.
1830
1831config ARM_ATAG_DTB_COMPAT
1832 bool "Supplement the appended DTB with traditional ATAG information"
1833 depends on ARM_APPENDED_DTB
1834 help
1835 Some old bootloaders can't be updated to a DTB capable one, yet
1836 they provide ATAGs with memory configuration, the ramdisk address,
1837 the kernel cmdline string, etc. Such information is dynamically
1838 provided by the bootloader and can't always be stored in a static
1839 DTB. To allow a device tree enabled kernel to be used with such
1840 bootloaders, this option allows zImage to extract the information
1841 from the ATAG list and store it at run time into the appended DTB.
1842
1843choice
1844 prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT
1845 default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1846
1847config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1848 bool "Use bootloader kernel arguments if available"
1849 help
1850 Uses the command-line options passed by the boot loader instead of
1851 the device tree bootargs property. If the boot loader doesn't provide
1852 any, the device tree bootargs property will be used.
1853
1854config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND
1855 bool "Extend with bootloader kernel arguments"
1856 help
1857 The command-line arguments provided by the boot loader will be
1858 appended to the the device tree bootargs property.
1859
1860endchoice
1861
1862config CMDLINE
1863 string "Default kernel command string"
1864 default ""
1865 help
1866 On some architectures (EBSA110 and CATS), there is currently no way
1867 for the boot loader to pass arguments to the kernel. For these
1868 architectures, you should supply some command-line options at build
1869 time by entering them here. As a minimum, you should specify the
1870 memory size and the root device (e.g., mem=64M root=/dev/nfs).
1871
1872choice
1873 prompt "Kernel command line type" if CMDLINE != ""
1874 default CMDLINE_FROM_BOOTLOADER
1875
1876config CMDLINE_FROM_BOOTLOADER
1877 bool "Use bootloader kernel arguments if available"
1878 help
1879 Uses the command-line options passed by the boot loader. If
1880 the boot loader doesn't provide any, the default kernel command
1881 string provided in CMDLINE will be used.
1882
1883config CMDLINE_EXTEND
1884 bool "Extend bootloader kernel arguments"
1885 help
1886 The command-line arguments provided by the boot loader will be
1887 appended to the default kernel command string.
1888
1889config CMDLINE_FORCE
1890 bool "Always use the default kernel command string"
1891 help
1892 Always use the default kernel command string, even if the boot
1893 loader passes other arguments to the kernel.
1894 This is useful if you cannot or don't want to change the
1895 command-line options your boot loader passes to the kernel.
1896endchoice
1897
1898config XIP_KERNEL
1899 bool "Kernel Execute-In-Place from ROM"
1900 depends on !ARM_LPAE && !ARCH_MULTIPLATFORM
1901 help
1902 Execute-In-Place allows the kernel to run from non-volatile storage
1903 directly addressable by the CPU, such as NOR flash. This saves RAM
1904 space since the text section of the kernel is not loaded from flash
1905 to RAM. Read-write sections, such as the data section and stack,
1906 are still copied to RAM. The XIP kernel is not compressed since
1907 it has to run directly from flash, so it will take more space to
1908 store it. The flash address used to link the kernel object files,
1909 and for storing it, is configuration dependent. Therefore, if you
1910 say Y here, you must know the proper physical address where to
1911 store the kernel image depending on your own flash memory usage.
1912
1913 Also note that the make target becomes "make xipImage" rather than
1914 "make zImage" or "make Image". The final kernel binary to put in
1915 ROM memory will be arch/arm/boot/xipImage.
1916
1917 If unsure, say N.
1918
1919config XIP_PHYS_ADDR
1920 hex "XIP Kernel Physical Location"
1921 depends on XIP_KERNEL
1922 default "0x00080000"
1923 help
1924 This is the physical address in your flash memory the kernel will
1925 be linked for and stored to. This address is dependent on your
1926 own flash usage.
1927
1928config XIP_DEFLATED_DATA
1929 bool "Store kernel .data section compressed in ROM"
1930 depends on XIP_KERNEL
1931 select ZLIB_INFLATE
1932 help
1933 Before the kernel is actually executed, its .data section has to be
1934 copied to RAM from ROM. This option allows for storing that data
1935 in compressed form and decompressed to RAM rather than merely being
1936 copied, saving some precious ROM space. A possible drawback is a
1937 slightly longer boot delay.
1938
1939config KEXEC
1940 bool "Kexec system call (EXPERIMENTAL)"
1941 depends on (!SMP || PM_SLEEP_SMP)
1942 depends on MMU
1943 select KEXEC_CORE
1944 help
1945 kexec is a system call that implements the ability to shutdown your
1946 current kernel, and to start another kernel. It is like a reboot
1947 but it is independent of the system firmware. And like a reboot
1948 you can start any kernel with it, not just Linux.
1949
1950 It is an ongoing process to be certain the hardware in a machine
1951 is properly shutdown, so do not be surprised if this code does not
1952 initially work for you.
1953
1954config ATAGS_PROC
1955 bool "Export atags in procfs"
1956 depends on ATAGS && KEXEC
1957 default y
1958 help
1959 Should the atags used to boot the kernel be exported in an "atags"
1960 file in procfs. Useful with kexec.
1961
1962config CRASH_DUMP
1963 bool "Build kdump crash kernel (EXPERIMENTAL)"
1964 help
1965 Generate crash dump after being started by kexec. This should
1966 be normally only set in special crash dump kernels which are
1967 loaded in the main kernel with kexec-tools into a specially
1968 reserved region and then later executed after a crash by
1969 kdump/kexec. The crash dump kernel must be compiled to a
1970 memory address not used by the main kernel
1971
1972 For more details see Documentation/admin-guide/kdump/kdump.rst
1973
1974config AUTO_ZRELADDR
1975 bool "Auto calculation of the decompressed kernel image address"
1976 help
1977 ZRELADDR is the physical address where the decompressed kernel
1978 image will be placed. If AUTO_ZRELADDR is selected, the address
1979 will be determined at run-time by masking the current IP with
1980 0xf8000000. This assumes the zImage being placed in the first 128MB
1981 from start of memory.
1982
1983config EFI_STUB
1984 bool
1985
1986config EFI
1987 bool "UEFI runtime support"
1988 depends on OF && !CPU_BIG_ENDIAN && MMU && AUTO_ZRELADDR && !XIP_KERNEL
1989 select UCS2_STRING
1990 select EFI_PARAMS_FROM_FDT
1991 select EFI_STUB
1992 select EFI_ARMSTUB
1993 select EFI_RUNTIME_WRAPPERS
1994 ---help---
1995 This option provides support for runtime services provided
1996 by UEFI firmware (such as non-volatile variables, realtime
1997 clock, and platform reset). A UEFI stub is also provided to
1998 allow the kernel to be booted as an EFI application. This
1999 is only useful for kernels that may run on systems that have
2000 UEFI firmware.
2001
2002config DMI
2003 bool "Enable support for SMBIOS (DMI) tables"
2004 depends on EFI
2005 default y
2006 help
2007 This enables SMBIOS/DMI feature for systems.
2008
2009 This option is only useful on systems that have UEFI firmware.
2010 However, even with this option, the resultant kernel should
2011 continue to boot on existing non-UEFI platforms.
2012
2013 NOTE: This does *NOT* enable or encourage the use of DMI quirks,
2014 i.e., the the practice of identifying the platform via DMI to
2015 decide whether certain workarounds for buggy hardware and/or
2016 firmware need to be enabled. This would require the DMI subsystem
2017 to be enabled much earlier than we do on ARM, which is non-trivial.
2018
2019endmenu
2020
2021menu "CPU Power Management"
2022
2023source "drivers/cpufreq/Kconfig"
2024
2025source "drivers/cpuidle/Kconfig"
2026
2027endmenu
2028
2029menu "Floating point emulation"
2030
2031comment "At least one emulation must be selected"
2032
2033config FPE_NWFPE
2034 bool "NWFPE math emulation"
2035 depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL
2036 ---help---
2037 Say Y to include the NWFPE floating point emulator in the kernel.
2038 This is necessary to run most binaries. Linux does not currently
2039 support floating point hardware so you need to say Y here even if
2040 your machine has an FPA or floating point co-processor podule.
2041
2042 You may say N here if you are going to load the Acorn FPEmulator
2043 early in the bootup.
2044
2045config FPE_NWFPE_XP
2046 bool "Support extended precision"
2047 depends on FPE_NWFPE
2048 help
2049 Say Y to include 80-bit support in the kernel floating-point
2050 emulator. Otherwise, only 32 and 64-bit support is compiled in.
2051 Note that gcc does not generate 80-bit operations by default,
2052 so in most cases this option only enlarges the size of the
2053 floating point emulator without any good reason.
2054
2055 You almost surely want to say N here.
2056
2057config FPE_FASTFPE
2058 bool "FastFPE math emulation (EXPERIMENTAL)"
2059 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3
2060 ---help---
2061 Say Y here to include the FAST floating point emulator in the kernel.
2062 This is an experimental much faster emulator which now also has full
2063 precision for the mantissa. It does not support any exceptions.
2064 It is very simple, and approximately 3-6 times faster than NWFPE.
2065
2066 It should be sufficient for most programs. It may be not suitable
2067 for scientific calculations, but you have to check this for yourself.
2068 If you do not feel you need a faster FP emulation you should better
2069 choose NWFPE.
2070
2071config VFP
2072 bool "VFP-format floating point maths"
2073 depends on CPU_V6 || CPU_V6K || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
2074 help
2075 Say Y to include VFP support code in the kernel. This is needed
2076 if your hardware includes a VFP unit.
2077
2078 Please see <file:Documentation/arm/vfp/release-notes.rst> for
2079 release notes and additional status information.
2080
2081 Say N if your target does not have VFP hardware.
2082
2083config VFPv3
2084 bool
2085 depends on VFP
2086 default y if CPU_V7
2087
2088config NEON
2089 bool "Advanced SIMD (NEON) Extension support"
2090 depends on VFPv3 && CPU_V7
2091 help
2092 Say Y to include support code for NEON, the ARMv7 Advanced SIMD
2093 Extension.
2094
2095config KERNEL_MODE_NEON
2096 bool "Support for NEON in kernel mode"
2097 depends on NEON && AEABI
2098 help
2099 Say Y to include support for NEON in kernel mode.
2100
2101endmenu
2102
2103menu "Power management options"
2104
2105source "kernel/power/Kconfig"
2106
2107config ARCH_SUSPEND_POSSIBLE
2108 depends on CPU_ARM920T || CPU_ARM926T || CPU_FEROCEON || CPU_SA1100 || \
2109 CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7M || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK
2110 def_bool y
2111
2112config ARM_CPU_SUSPEND
2113 def_bool PM_SLEEP || BL_SWITCHER || ARM_PSCI_FW
2114 depends on ARCH_SUSPEND_POSSIBLE
2115
2116config ARCH_HIBERNATION_POSSIBLE
2117 bool
2118 depends on MMU
2119 default y if ARCH_SUSPEND_POSSIBLE
2120
2121endmenu
2122
2123source "drivers/firmware/Kconfig"
2124
2125if CRYPTO
2126source "arch/arm/crypto/Kconfig"
2127endif
2128
2129source "arch/arm/kvm/Kconfig"
2130source "arch/arm/Kconfig.assembler"