blob: a8ba03171f5fc681280c227089b0d966b2b23e10 [file] [log] [blame]
rjw1f884582022-01-06 17:20:42 +08001# SPDX-License-Identifier: GPL-2.0
2config ARM
3 bool
4 default y
5 select ARCH_CLOCKSOURCE_DATA
6 select ARCH_HAS_DEBUG_VIRTUAL
7 select ARCH_HAS_DEVMEM_IS_ALLOWED
8 select ARCH_HAS_ELF_RANDOMIZE
9 select ARCH_HAS_SET_MEMORY
10 select ARCH_HAS_STRICT_KERNEL_RWX if MMU && !XIP_KERNEL
11 select ARCH_HAS_STRICT_MODULE_RWX if MMU
12 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
13 select ARCH_HAVE_CUSTOM_GPIO_H
14 select ARCH_HAS_GCOV_PROFILE_ALL
15 select ARCH_MIGHT_HAVE_PC_PARPORT
16 select ARCH_OPTIONAL_KERNEL_RWX if ARCH_HAS_STRICT_KERNEL_RWX
17 select ARCH_OPTIONAL_KERNEL_RWX_DEFAULT if CPU_V7
18 select ARCH_SUPPORTS_ATOMIC_RMW
19 select ARCH_USE_BUILTIN_BSWAP
20 select ARCH_USE_CMPXCHG_LOCKREF
21 select ARCH_WANT_IPC_PARSE_VERSION
22 select BUILDTIME_EXTABLE_SORT if MMU
23 select CLONE_BACKWARDS
24 select CPU_PM if (SUSPEND || CPU_IDLE)
25 select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS
26 select DMA_NOOP_OPS if !MMU
27 select EDAC_SUPPORT
28 select EDAC_ATOMIC_SCRUB
29 select GENERIC_ALLOCATOR
30 select GENERIC_ARCH_TOPOLOGY if ARM_CPU_TOPOLOGY
31 select GENERIC_ATOMIC64 if (CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI)
32 select GENERIC_CLOCKEVENTS_BROADCAST if SMP
33 select GENERIC_CPU_AUTOPROBE
34 select GENERIC_EARLY_IOREMAP
35 select GENERIC_IDLE_POLL_SETUP
36 select GENERIC_IRQ_PROBE
37 select GENERIC_IRQ_SHOW
38 select GENERIC_IRQ_SHOW_LEVEL
39 select GENERIC_PCI_IOMAP
40 select GENERIC_SCHED_CLOCK
41 select GENERIC_SMP_IDLE_THREAD
42 select GENERIC_STRNCPY_FROM_USER
43 select GENERIC_STRNLEN_USER
44 select HANDLE_DOMAIN_IRQ
45 select HARDIRQS_SW_RESEND
46 select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
47 select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
48 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32 && MMU
49 select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32 && MMU
50 select HAVE_ARCH_MMAP_RND_BITS if MMU
51 select HAVE_ARCH_SECCOMP_FILTER if (AEABI && !OABI_COMPAT)
52 select HAVE_ARCH_TRACEHOOK
53 select HAVE_ARM_SMCCC if CPU_V7
54 select HAVE_EBPF_JIT if !CPU_ENDIAN_BE32
55 select HAVE_CC_STACKPROTECTOR
56 select HAVE_CONTEXT_TRACKING
57 select HAVE_C_RECORDMCOUNT
58 select HAVE_DEBUG_KMEMLEAK
59 select HAVE_DMA_API_DEBUG
60 select HAVE_DMA_CONTIGUOUS if MMU
61 select HAVE_DYNAMIC_FTRACE if (!XIP_KERNEL) && !CPU_ENDIAN_BE32 && MMU
62 select HAVE_DYNAMIC_FTRACE_WITH_REGS if HAVE_DYNAMIC_FTRACE
63 select HAVE_EFFICIENT_UNALIGNED_ACCESS if (CPU_V6 || CPU_V6K || CPU_V7) && MMU
64 select HAVE_EXIT_THREAD
65 select HAVE_FTRACE_MCOUNT_RECORD if (!XIP_KERNEL)
66 select HAVE_FUNCTION_GRAPH_TRACER if (!THUMB2_KERNEL)
67 select HAVE_FUNCTION_TRACER if (!XIP_KERNEL)
68 select HAVE_GCC_PLUGINS
69 select HAVE_GENERIC_DMA_COHERENT
70 select HAVE_HW_BREAKPOINT if (PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7))
71 select HAVE_IDE if PCI || ISA || PCMCIA
72 select HAVE_IRQ_TIME_ACCOUNTING
73 select HAVE_KERNEL_GZIP
74 select HAVE_KERNEL_LZ4
75 select HAVE_KERNEL_LZMA
76 select HAVE_KERNEL_LZO
77 select HAVE_KERNEL_XZ
78 select HAVE_KPROBES if !XIP_KERNEL && !CPU_ENDIAN_BE32 && !CPU_V7M
79 select HAVE_KRETPROBES if (HAVE_KPROBES)
80 select HAVE_MEMBLOCK
81 select HAVE_MOD_ARCH_SPECIFIC
82 select HAVE_NMI
83 select HAVE_OPROFILE if (HAVE_PERF_EVENTS)
84 select HAVE_OPTPROBES if !THUMB2_KERNEL
85 select HAVE_PERF_EVENTS
86 select HAVE_PERF_REGS
87 select HAVE_PERF_USER_STACK_DUMP
88 select HAVE_RCU_TABLE_FREE if (SMP && ARM_LPAE)
89 select HAVE_REGS_AND_STACK_ACCESS_API
90 select HAVE_SYSCALL_TRACEPOINTS
91 select HAVE_UID16
92 select HAVE_VIRT_CPU_ACCOUNTING_GEN
93 select IRQ_FORCED_THREADING
94 select MODULES_USE_ELF_REL
95 select NO_BOOTMEM
96 select OF_EARLY_FLATTREE if OF
97 select OF_RESERVED_MEM if OF
98 select OLD_SIGACTION
99 select OLD_SIGSUSPEND3
100 select PERF_USE_VMALLOC
101 select RTC_LIB
102 select SYS_SUPPORTS_APM_EMULATION
103 # Above selects are sorted alphabetically; please add new ones
104 # according to that. Thanks.
105 help
106 The ARM series is a line of low-power-consumption RISC chip designs
107 licensed by ARM Ltd and targeted at embedded applications and
108 handhelds such as the Compaq IPAQ. ARM-based PCs are no longer
109 manufactured, but legacy ARM-based PC hardware remains popular in
110 Europe. There is an ARM Linux project with a web page at
111 <http://www.arm.linux.org.uk/>.
112
113config ARM_HAS_SG_CHAIN
114 select ARCH_HAS_SG_CHAIN
115 bool
116
117config NEED_SG_DMA_LENGTH
118 bool
119
120config ARM_DMA_USE_IOMMU
121 bool
122 select ARM_HAS_SG_CHAIN
123 select NEED_SG_DMA_LENGTH
124
125if ARM_DMA_USE_IOMMU
126
127config ARM_DMA_IOMMU_ALIGNMENT
128 int "Maximum PAGE_SIZE order of alignment for DMA IOMMU buffers"
129 range 4 9
130 default 8
131 help
132 DMA mapping framework by default aligns all buffers to the smallest
133 PAGE_SIZE order which is greater than or equal to the requested buffer
134 size. This works well for buffers up to a few hundreds kilobytes, but
135 for larger buffers it just a waste of address space. Drivers which has
136 relatively small addressing window (like 64Mib) might run out of
137 virtual space with just a few allocations.
138
139 With this parameter you can specify the maximum PAGE_SIZE order for
140 DMA IOMMU buffers. Larger buffers will be aligned only to this
141 specified order. The order is expressed as a power of two multiplied
142 by the PAGE_SIZE.
143
144endif
145
146config MIGHT_HAVE_PCI
147 bool
148
149config SYS_SUPPORTS_APM_EMULATION
150 bool
151
152config HAVE_TCM
153 bool
154 select GENERIC_ALLOCATOR
155
156config HAVE_PROC_CPU
157 bool
158
159config NO_IOPORT_MAP
160 bool
161
162config EISA
163 bool
164 ---help---
165 The Extended Industry Standard Architecture (EISA) bus was
166 developed as an open alternative to the IBM MicroChannel bus.
167
168 The EISA bus provided some of the features of the IBM MicroChannel
169 bus while maintaining backward compatibility with cards made for
170 the older ISA bus. The EISA bus saw limited use between 1988 and
171 1995 when it was made obsolete by the PCI bus.
172
173 Say Y here if you are building a kernel for an EISA-based machine.
174
175 Otherwise, say N.
176
177config SBUS
178 bool
179
180config STACKTRACE_SUPPORT
181 bool
182 default y
183
184config LOCKDEP_SUPPORT
185 bool
186 default y
187
188config TRACE_IRQFLAGS_SUPPORT
189 bool
190 default !CPU_V7M
191
192config RWSEM_XCHGADD_ALGORITHM
193 bool
194 default y
195
196config ARCH_HAS_ILOG2_U32
197 bool
198
199config ARCH_HAS_ILOG2_U64
200 bool
201
202config ARCH_HAS_BANDGAP
203 bool
204
205config FIX_EARLYCON_MEM
206 def_bool y if MMU
207
208config GENERIC_HWEIGHT
209 bool
210 default y
211
212config GENERIC_CALIBRATE_DELAY
213 bool
214 default y
215
216config ARCH_MAY_HAVE_PC_FDC
217 bool
218
219config ZONE_DMA
220 bool
221
222config NEED_DMA_MAP_STATE
223 def_bool y
224
225config ARCH_SUPPORTS_UPROBES
226 def_bool y
227
228config ARCH_HAS_DMA_SET_COHERENT_MASK
229 bool
230
231config GENERIC_ISA_DMA
232 bool
233
234config FIQ
235 bool
236
237config NEED_RET_TO_USER
238 bool
239
240config ARCH_MTD_XIP
241 bool
242
243config VECTORS_BASE
244 hex
245 default 0xffff0000 if MMU || CPU_HIGH_VECTOR
246 default DRAM_BASE if REMAP_VECTORS_TO_RAM
247 default 0x00000000
248 help
249 The base address of exception vectors. This must be two pages
250 in size.
251
252config ARM_PATCH_PHYS_VIRT
253 bool "Patch physical to virtual translations at runtime" if EMBEDDED
254 default y
255 depends on !XIP_KERNEL && MMU
256 help
257 Patch phys-to-virt and virt-to-phys translation functions at
258 boot and module load time according to the position of the
259 kernel in system memory.
260
261 This can only be used with non-XIP MMU kernels where the base
262 of physical memory is at a 16MB boundary.
263
264 Only disable this option if you know that you do not require
265 this feature (eg, building a kernel for a single machine) and
266 you need to shrink the kernel to the minimal size.
267
268config NEED_MACH_IO_H
269 bool
270 help
271 Select this when mach/io.h is required to provide special
272 definitions for this platform. The need for mach/io.h should
273 be avoided when possible.
274
275config NEED_MACH_MEMORY_H
276 bool
277 help
278 Select this when mach/memory.h is required to provide special
279 definitions for this platform. The need for mach/memory.h should
280 be avoided when possible.
281
282config PHYS_OFFSET
283 hex "Physical address of main memory" if MMU
284 depends on !ARM_PATCH_PHYS_VIRT
285 default DRAM_BASE if !MMU
286 default 0x00000000 if ARCH_EBSA110 || \
287 ARCH_FOOTBRIDGE || \
288 ARCH_INTEGRATOR || \
289 ARCH_IOP13XX || \
290 ARCH_KS8695 || \
291 ARCH_REALVIEW
292 default 0x10000000 if ARCH_OMAP1 || ARCH_RPC
293 default 0x20000000 if ARCH_S5PV210
294 default 0xc0000000 if ARCH_SA1100
295 help
296 Please provide the physical address corresponding to the
297 location of main memory in your system.
298
299config GENERIC_BUG
300 def_bool y
301 depends on BUG
302
303config PGTABLE_LEVELS
304 int
305 default 3 if ARM_LPAE
306 default 2
307
308source "init/Kconfig"
309
310source "kernel/Kconfig.freezer"
311
312menu "System Type"
313
314config MMU
315 bool "MMU-based Paged Memory Management Support"
316 default y
317 help
318 Select if you want MMU-based virtualised addressing space
319 support by paged memory management. If unsure, say 'Y'.
320
321config ARCH_MMAP_RND_BITS_MIN
322 default 8
323
324config ARCH_MMAP_RND_BITS_MAX
325 default 14 if PAGE_OFFSET=0x40000000
326 default 15 if PAGE_OFFSET=0x80000000
327 default 16
328
329#
330# The "ARM system type" choice list is ordered alphabetically by option
331# text. Please add new entries in the option alphabetic order.
332#
333choice
334 prompt "ARM system type"
335 default ARM_SINGLE_ARMV7M if !MMU
336 default ARCH_MULTIPLATFORM if MMU
337
338config ARCH_MULTIPLATFORM
339 bool "Allow multiple platforms to be selected"
340 depends on MMU
341 select ARM_HAS_SG_CHAIN
342 select ARM_PATCH_PHYS_VIRT
343 select AUTO_ZRELADDR
344 select TIMER_OF
345 select COMMON_CLK
346 select GENERIC_CLOCKEVENTS
347 select MIGHT_HAVE_PCI
348 select MULTI_IRQ_HANDLER
349 select PCI_DOMAINS if PCI
350 select SPARSE_IRQ
351 select USE_OF
352
353config ARM_SINGLE_ARMV7M
354 bool "ARMv7-M based platforms (Cortex-M0/M3/M4)"
355 depends on !MMU
356 select ARM_NVIC
357 select AUTO_ZRELADDR
358 select TIMER_OF
359 select COMMON_CLK
360 select CPU_V7M
361 select GENERIC_CLOCKEVENTS
362 select NO_IOPORT_MAP
363 select SPARSE_IRQ
364 select USE_OF
365
366config ARCH_EBSA110
367 bool "EBSA-110"
368 select ARCH_USES_GETTIMEOFFSET
369 select CPU_SA110
370 select ISA
371 select NEED_MACH_IO_H
372 select NEED_MACH_MEMORY_H
373 select NO_IOPORT_MAP
374 help
375 This is an evaluation board for the StrongARM processor available
376 from Digital. It has limited hardware on-board, including an
377 Ethernet interface, two PCMCIA sockets, two serial ports and a
378 parallel port.
379
380config ARCH_EP93XX
381 bool "EP93xx-based"
382 select ARCH_HAS_HOLES_MEMORYMODEL
383 select ARM_AMBA
384 imply ARM_PATCH_PHYS_VIRT
385 select ARM_VIC
386 select AUTO_ZRELADDR
387 select CLKDEV_LOOKUP
388 select CLKSRC_MMIO
389 select CPU_ARM920T
390 select GENERIC_CLOCKEVENTS
391 select GPIOLIB
392 help
393 This enables support for the Cirrus EP93xx series of CPUs.
394
395config ARCH_FOOTBRIDGE
396 bool "FootBridge"
397 select CPU_SA110
398 select FOOTBRIDGE
399 select GENERIC_CLOCKEVENTS
400 select HAVE_IDE
401 select NEED_MACH_IO_H if !MMU
402 select NEED_MACH_MEMORY_H
403 help
404 Support for systems based on the DC21285 companion chip
405 ("FootBridge"), such as the Simtec CATS and the Rebel NetWinder.
406
407config ARCH_NETX
408 bool "Hilscher NetX based"
409 select ARM_VIC
410 select CLKSRC_MMIO
411 select CPU_ARM926T
412 select GENERIC_CLOCKEVENTS
413 help
414 This enables support for systems based on the Hilscher NetX Soc
415
416config ARCH_IOP13XX
417 bool "IOP13xx-based"
418 depends on MMU
419 select CPU_XSC3
420 select NEED_MACH_MEMORY_H
421 select NEED_RET_TO_USER
422 select PCI
423 select PLAT_IOP
424 select VMSPLIT_1G
425 select SPARSE_IRQ
426 help
427 Support for Intel's IOP13XX (XScale) family of processors.
428
429config ARCH_IOP32X
430 bool "IOP32x-based"
431 depends on MMU
432 select CPU_XSCALE
433 select GPIO_IOP
434 select GPIOLIB
435 select NEED_RET_TO_USER
436 select PCI
437 select PLAT_IOP
438 help
439 Support for Intel's 80219 and IOP32X (XScale) family of
440 processors.
441
442config ARCH_IOP33X
443 bool "IOP33x-based"
444 depends on MMU
445 select CPU_XSCALE
446 select GPIO_IOP
447 select GPIOLIB
448 select NEED_RET_TO_USER
449 select PCI
450 select PLAT_IOP
451 help
452 Support for Intel's IOP33X (XScale) family of processors.
453
454config ARCH_IXP4XX
455 bool "IXP4xx-based"
456 depends on MMU
457 select ARCH_HAS_DMA_SET_COHERENT_MASK
458 select ARCH_SUPPORTS_BIG_ENDIAN
459 select CLKSRC_MMIO
460 select CPU_XSCALE
461 select DMABOUNCE if PCI
462 select GENERIC_CLOCKEVENTS
463 select GPIOLIB
464 select MIGHT_HAVE_PCI
465 select NEED_MACH_IO_H
466 select USB_EHCI_BIG_ENDIAN_DESC
467 select USB_EHCI_BIG_ENDIAN_MMIO
468 help
469 Support for Intel's IXP4XX (XScale) family of processors.
470
471config ARCH_DOVE
472 bool "Marvell Dove"
473 select CPU_PJ4
474 select GENERIC_CLOCKEVENTS
475 select GPIOLIB
476 select MIGHT_HAVE_PCI
477 select MULTI_IRQ_HANDLER
478 select MVEBU_MBUS
479 select PINCTRL
480 select PINCTRL_DOVE
481 select PLAT_ORION_LEGACY
482 select SPARSE_IRQ
483 select PM_GENERIC_DOMAINS if PM
484 help
485 Support for the Marvell Dove SoC 88AP510
486
487config ARCH_KS8695
488 bool "Micrel/Kendin KS8695"
489 select CLKSRC_MMIO
490 select CPU_ARM922T
491 select GENERIC_CLOCKEVENTS
492 select GPIOLIB
493 select NEED_MACH_MEMORY_H
494 help
495 Support for Micrel/Kendin KS8695 "Centaur" (ARM922T) based
496 System-on-Chip devices.
497
498config ARCH_W90X900
499 bool "Nuvoton W90X900 CPU"
500 select CLKDEV_LOOKUP
501 select CLKSRC_MMIO
502 select CPU_ARM926T
503 select GENERIC_CLOCKEVENTS
504 select GPIOLIB
505 help
506 Support for Nuvoton (Winbond logic dept.) ARM9 processor,
507 At present, the w90x900 has been renamed nuc900, regarding
508 the ARM series product line, you can login the following
509 link address to know more.
510
511 <http://www.nuvoton.com/hq/enu/ProductAndSales/ProductLines/
512 ConsumerElectronicsIC/ARMMicrocontroller/ARMMicrocontroller>
513
514config ARCH_LPC32XX
515 bool "NXP LPC32XX"
516 select ARM_AMBA
517 select CLKDEV_LOOKUP
518 select CLKSRC_LPC32XX
519 select COMMON_CLK
520 select CPU_ARM926T
521 select GENERIC_CLOCKEVENTS
522 select GPIOLIB
523 select MULTI_IRQ_HANDLER
524 select SPARSE_IRQ
525 select USE_OF
526 help
527 Support for the NXP LPC32XX family of processors
528
529config ARCH_PXA
530 bool "PXA2xx/PXA3xx-based"
531 depends on MMU
532 select ARCH_MTD_XIP
533 select ARM_CPU_SUSPEND if PM
534 select AUTO_ZRELADDR
535 select COMMON_CLK
536 select CLKDEV_LOOKUP
537 select CLKSRC_PXA
538 select CLKSRC_MMIO
539 select TIMER_OF
540 select CPU_XSCALE if !CPU_XSC3
541 select GENERIC_CLOCKEVENTS
542 select GPIO_PXA
543 select GPIOLIB
544 select HAVE_IDE
545 select IRQ_DOMAIN
546 select MULTI_IRQ_HANDLER
547 select PLAT_PXA
548 select SPARSE_IRQ
549 help
550 Support for Intel/Marvell's PXA2xx/PXA3xx processor line.
551
552config ARCH_RPC
553 bool "RiscPC"
554 depends on MMU
555 select ARCH_ACORN
556 select ARCH_MAY_HAVE_PC_FDC
557 select ARCH_SPARSEMEM_ENABLE
558 select ARCH_USES_GETTIMEOFFSET
559 select CPU_SA110
560 select FIQ
561 select HAVE_IDE
562 select HAVE_PATA_PLATFORM
563 select ISA_DMA_API
564 select NEED_MACH_IO_H
565 select NEED_MACH_MEMORY_H
566 select NO_IOPORT_MAP
567 help
568 On the Acorn Risc-PC, Linux can support the internal IDE disk and
569 CD-ROM interface, serial and parallel port, and the floppy drive.
570
571config ARCH_SA1100
572 bool "SA1100-based"
573 select ARCH_MTD_XIP
574 select ARCH_SPARSEMEM_ENABLE
575 select CLKDEV_LOOKUP
576 select CLKSRC_MMIO
577 select CLKSRC_PXA
578 select TIMER_OF if OF
579 select CPU_FREQ
580 select CPU_SA1100
581 select GENERIC_CLOCKEVENTS
582 select GPIOLIB
583 select HAVE_IDE
584 select IRQ_DOMAIN
585 select ISA
586 select MULTI_IRQ_HANDLER
587 select NEED_MACH_MEMORY_H
588 select SPARSE_IRQ
589 help
590 Support for StrongARM 11x0 based boards.
591
592config ARCH_S3C24XX
593 bool "Samsung S3C24XX SoCs"
594 select ATAGS
595 select CLKDEV_LOOKUP
596 select CLKSRC_SAMSUNG_PWM
597 select GENERIC_CLOCKEVENTS
598 select GPIO_SAMSUNG
599 select GPIOLIB
600 select HAVE_S3C2410_I2C if I2C
601 select HAVE_S3C2410_WATCHDOG if WATCHDOG
602 select HAVE_S3C_RTC if RTC_CLASS
603 select MULTI_IRQ_HANDLER
604 select NEED_MACH_IO_H
605 select SAMSUNG_ATAGS
606 help
607 Samsung S3C2410, S3C2412, S3C2413, S3C2416, S3C2440, S3C2442, S3C2443
608 and S3C2450 SoCs based systems, such as the Simtec Electronics BAST
609 (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or the
610 Samsung SMDK2410 development board (and derivatives).
611
612config ARCH_DAVINCI
613 bool "TI DaVinci"
614 select ARCH_HAS_HOLES_MEMORYMODEL
615 select CLKDEV_LOOKUP
616 select CPU_ARM926T
617 select GENERIC_ALLOCATOR
618 select GENERIC_CLOCKEVENTS
619 select GENERIC_IRQ_CHIP
620 select GPIOLIB
621 select HAVE_IDE
622 select USE_OF
623 select ZONE_DMA
624 help
625 Support for TI's DaVinci platform.
626
627config ARCH_OMAP1
628 bool "TI OMAP1"
629 depends on MMU
630 select ARCH_HAS_HOLES_MEMORYMODEL
631 select ARCH_OMAP
632 select CLKDEV_LOOKUP
633 select CLKSRC_MMIO
634 select GENERIC_CLOCKEVENTS
635 select GENERIC_IRQ_CHIP
636 select GPIOLIB
637 select HAVE_IDE
638 select IRQ_DOMAIN
639 select MULTI_IRQ_HANDLER
640 select NEED_MACH_IO_H if PCCARD
641 select NEED_MACH_MEMORY_H
642 select SPARSE_IRQ
643 help
644 Support for older TI OMAP1 (omap7xx, omap15xx or omap16xx)
645
646endchoice
647
648menu "Multiple platform selection"
649 depends on ARCH_MULTIPLATFORM
650
651comment "CPU Core family selection"
652
653config ARCH_MULTI_V4
654 bool "ARMv4 based platforms (FA526)"
655 depends on !ARCH_MULTI_V6_V7
656 select ARCH_MULTI_V4_V5
657 select CPU_FA526
658
659config ARCH_MULTI_V4T
660 bool "ARMv4T based platforms (ARM720T, ARM920T, ...)"
661 depends on !ARCH_MULTI_V6_V7
662 select ARCH_MULTI_V4_V5
663 select CPU_ARM920T if !(CPU_ARM7TDMI || CPU_ARM720T || \
664 CPU_ARM740T || CPU_ARM9TDMI || CPU_ARM922T || \
665 CPU_ARM925T || CPU_ARM940T)
666
667config ARCH_MULTI_V5
668 bool "ARMv5 based platforms (ARM926T, XSCALE, PJ1, ...)"
669 depends on !ARCH_MULTI_V6_V7
670 select ARCH_MULTI_V4_V5
671 select CPU_ARM926T if !(CPU_ARM946E || CPU_ARM1020 || \
672 CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || \
673 CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_FEROCEON)
674
675config ARCH_MULTI_V4_V5
676 bool
677
678config ARCH_MULTI_V6
679 bool "ARMv6 based platforms (ARM11)"
680 select ARCH_MULTI_V6_V7
681 select CPU_V6K
682
683config ARCH_MULTI_V7
684 bool "ARMv7 based platforms (Cortex-A, PJ4, Scorpion, Krait)"
685 default y
686 select ARCH_MULTI_V6_V7
687 select CPU_V7
688 select HAVE_SMP
689
690config ARCH_MULTI_V6_V7
691 bool
692 select MIGHT_HAVE_CACHE_L2X0
693
694config ARCH_MULTI_CPU_AUTO
695 def_bool !(ARCH_MULTI_V4 || ARCH_MULTI_V4T || ARCH_MULTI_V6_V7)
696 select ARCH_MULTI_V5
697
698endmenu
699
700config ARCH_VIRT
701 bool "Dummy Virtual Machine"
702 depends on ARCH_MULTI_V7
703 select ARM_AMBA
704 select ARM_GIC
705 select ARM_GIC_V2M if PCI
706 select ARM_GIC_V3
707 select ARM_GIC_V3_ITS if PCI
708 select ARM_PSCI
709 select HAVE_ARM_ARCH_TIMER
710
711#
712# This is sorted alphabetically by mach-* pathname. However, plat-*
713# Kconfigs may be included either alphabetically (according to the
714# plat- suffix) or along side the corresponding mach-* source.
715#
716source "arch/arm/mach-mvebu/Kconfig"
717
718source "arch/arm/mach-actions/Kconfig"
719
720source "arch/arm/mach-alpine/Kconfig"
721
722source "arch/arm/mach-artpec/Kconfig"
723
724source "arch/arm/mach-asm9260/Kconfig"
725
726source "arch/arm/mach-at91/Kconfig"
727
728source "arch/arm/mach-axxia/Kconfig"
729
730source "arch/arm/mach-bcm/Kconfig"
731
732source "arch/arm/mach-berlin/Kconfig"
733
734source "arch/arm/mach-clps711x/Kconfig"
735
736source "arch/arm/mach-cns3xxx/Kconfig"
737
738source "arch/arm/mach-davinci/Kconfig"
739
740source "arch/arm/mach-digicolor/Kconfig"
741
742source "arch/arm/mach-dove/Kconfig"
743
744source "arch/arm/mach-ep93xx/Kconfig"
745
746source "arch/arm/mach-footbridge/Kconfig"
747
748source "arch/arm/mach-gemini/Kconfig"
749
750source "arch/arm/mach-highbank/Kconfig"
751
752source "arch/arm/mach-hisi/Kconfig"
753
754source "arch/arm/mach-integrator/Kconfig"
755
756source "arch/arm/mach-iop32x/Kconfig"
757
758source "arch/arm/mach-iop33x/Kconfig"
759
760source "arch/arm/mach-iop13xx/Kconfig"
761
762source "arch/arm/mach-ixp4xx/Kconfig"
763
764source "arch/arm/mach-keystone/Kconfig"
765
766source "arch/arm/mach-ks8695/Kconfig"
767
768source "arch/arm/mach-meson/Kconfig"
769
770source "arch/arm/mach-moxart/Kconfig"
771
772source "arch/arm/mach-aspeed/Kconfig"
773
774source "arch/arm/mach-mv78xx0/Kconfig"
775
776source "arch/arm/mach-imx/Kconfig"
777
778source "arch/arm/mach-mediatek/Kconfig"
779
780source "arch/arm/mach-mxs/Kconfig"
781
782source "arch/arm/mach-netx/Kconfig"
783
784source "arch/arm/mach-nomadik/Kconfig"
785
786source "arch/arm/mach-nspire/Kconfig"
787
788source "arch/arm/plat-omap/Kconfig"
789
790source "arch/arm/mach-omap1/Kconfig"
791
792source "arch/arm/mach-omap2/Kconfig"
793
794source "arch/arm/mach-orion5x/Kconfig"
795
796source "arch/arm/mach-picoxcell/Kconfig"
797
798source "arch/arm/mach-pxa/Kconfig"
799source "arch/arm/plat-pxa/Kconfig"
800
801source "arch/arm/mach-mmp/Kconfig"
802
803source "arch/arm/mach-oxnas/Kconfig"
804
805source "arch/arm/mach-qcom/Kconfig"
806
807source "arch/arm/mach-realview/Kconfig"
808
809source "arch/arm/mach-rockchip/Kconfig"
810
811source "arch/arm/mach-sa1100/Kconfig"
812
813source "arch/arm/mach-socfpga/Kconfig"
814
815source "arch/arm/mach-spear/Kconfig"
816
817source "arch/arm/mach-sti/Kconfig"
818
819source "arch/arm/mach-stm32/Kconfig"
820
821source "arch/arm/mach-s3c24xx/Kconfig"
822
823source "arch/arm/mach-s3c64xx/Kconfig"
824
825source "arch/arm/mach-s5pv210/Kconfig"
826
827source "arch/arm/mach-exynos/Kconfig"
828source "arch/arm/plat-samsung/Kconfig"
829
830source "arch/arm/mach-shmobile/Kconfig"
831
832source "arch/arm/mach-sunxi/Kconfig"
833
834source "arch/arm/mach-prima2/Kconfig"
835
836source "arch/arm/mach-tango/Kconfig"
837
838source "arch/arm/mach-tegra/Kconfig"
839
840source "arch/arm/mach-u300/Kconfig"
841
842source "arch/arm/mach-uniphier/Kconfig"
843
844source "arch/arm/mach-ux500/Kconfig"
845
846source "arch/arm/mach-versatile/Kconfig"
847
848source "arch/arm/mach-vexpress/Kconfig"
849source "arch/arm/plat-versatile/Kconfig"
850
851source "arch/arm/mach-vt8500/Kconfig"
852
853source "arch/arm/mach-w90x900/Kconfig"
854
855source "arch/arm/mach-zx/Kconfig"
856
857source "arch/arm/mach-zynq/Kconfig"
858
859# ARMv7-M architecture
860config ARCH_EFM32
861 bool "Energy Micro efm32"
862 depends on ARM_SINGLE_ARMV7M
863 select GPIOLIB
864 help
865 Support for Energy Micro's (now Silicon Labs) efm32 Giant Gecko
866 processors.
867
868config ARCH_LPC18XX
869 bool "NXP LPC18xx/LPC43xx"
870 depends on ARM_SINGLE_ARMV7M
871 select ARCH_HAS_RESET_CONTROLLER
872 select ARM_AMBA
873 select CLKSRC_LPC32XX
874 select PINCTRL
875 help
876 Support for NXP's LPC18xx Cortex-M3 and LPC43xx Cortex-M4
877 high performance microcontrollers.
878
879config ARCH_MPS2
880 bool "ARM MPS2 platform"
881 depends on ARM_SINGLE_ARMV7M
882 select ARM_AMBA
883 select CLKSRC_MPS2
884 help
885 Support for Cortex-M Prototyping System (or V2M-MPS2) which comes
886 with a range of available cores like Cortex-M3/M4/M7.
887
888 Please, note that depends which Application Note is used memory map
889 for the platform may vary, so adjustment of RAM base might be needed.
890
891# Definitions to make life easier
892config ARCH_ACORN
893 bool
894
895config PLAT_IOP
896 bool
897 select GENERIC_CLOCKEVENTS
898
899config PLAT_ORION
900 bool
901 select CLKSRC_MMIO
902 select COMMON_CLK
903 select GENERIC_IRQ_CHIP
904 select IRQ_DOMAIN
905
906config PLAT_ORION_LEGACY
907 bool
908 select PLAT_ORION
909
910config PLAT_PXA
911 bool
912
913config PLAT_VERSATILE
914 bool
915
916source "arch/arm/firmware/Kconfig"
917
918source arch/arm/mm/Kconfig
919
920config IWMMXT
921 bool "Enable iWMMXt support"
922 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B
923 default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 || CPU_PJ4B
924 help
925 Enable support for iWMMXt context switching at run time if
926 running on a CPU that supports it.
927
928config MULTI_IRQ_HANDLER
929 bool
930 help
931 Allow each machine to specify it's own IRQ handler at run time.
932
933if !MMU
934source "arch/arm/Kconfig-nommu"
935endif
936
937config PJ4B_ERRATA_4742
938 bool "PJ4B Errata 4742: IDLE Wake Up Commands can Cause the CPU Core to Cease Operation"
939 depends on CPU_PJ4B && MACH_ARMADA_370
940 default y
941 help
942 When coming out of either a Wait for Interrupt (WFI) or a Wait for
943 Event (WFE) IDLE states, a specific timing sensitivity exists between
944 the retiring WFI/WFE instructions and the newly issued subsequent
945 instructions. This sensitivity can result in a CPU hang scenario.
946 Workaround:
947 The software must insert either a Data Synchronization Barrier (DSB)
948 or Data Memory Barrier (DMB) command immediately after the WFI/WFE
949 instruction
950
951config ARM_ERRATA_326103
952 bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory"
953 depends on CPU_V6
954 help
955 Executing a SWP instruction to read-only memory does not set bit 11
956 of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to
957 treat the access as a read, preventing a COW from occurring and
958 causing the faulting task to livelock.
959
960config ARM_ERRATA_411920
961 bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
962 depends on CPU_V6 || CPU_V6K
963 help
964 Invalidation of the Instruction Cache operation can
965 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
966 It does not affect the MPCore. This option enables the ARM Ltd.
967 recommended workaround.
968
969config ARM_ERRATA_430973
970 bool "ARM errata: Stale prediction on replaced interworking branch"
971 depends on CPU_V7
972 help
973 This option enables the workaround for the 430973 Cortex-A8
974 r1p* erratum. If a code sequence containing an ARM/Thumb
975 interworking branch is replaced with another code sequence at the
976 same virtual address, whether due to self-modifying code or virtual
977 to physical address re-mapping, Cortex-A8 does not recover from the
978 stale interworking branch prediction. This results in Cortex-A8
979 executing the new code sequence in the incorrect ARM or Thumb state.
980 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
981 and also flushes the branch target cache at every context switch.
982 Note that setting specific bits in the ACTLR register may not be
983 available in non-secure mode.
984
985config ARM_ERRATA_458693
986 bool "ARM errata: Processor deadlock when a false hazard is created"
987 depends on CPU_V7
988 depends on !ARCH_MULTIPLATFORM
989 help
990 This option enables the workaround for the 458693 Cortex-A8 (r2p0)
991 erratum. For very specific sequences of memory operations, it is
992 possible for a hazard condition intended for a cache line to instead
993 be incorrectly associated with a different cache line. This false
994 hazard might then cause a processor deadlock. The workaround enables
995 the L1 caching of the NEON accesses and disables the PLD instruction
996 in the ACTLR register. Note that setting specific bits in the ACTLR
997 register may not be available in non-secure mode.
998
999config ARM_ERRATA_460075
1000 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
1001 depends on CPU_V7
1002 depends on !ARCH_MULTIPLATFORM
1003 help
1004 This option enables the workaround for the 460075 Cortex-A8 (r2p0)
1005 erratum. Any asynchronous access to the L2 cache may encounter a
1006 situation in which recent store transactions to the L2 cache are lost
1007 and overwritten with stale memory contents from external memory. The
1008 workaround disables the write-allocate mode for the L2 cache via the
1009 ACTLR register. Note that setting specific bits in the ACTLR register
1010 may not be available in non-secure mode.
1011
1012config ARM_ERRATA_742230
1013 bool "ARM errata: DMB operation may be faulty"
1014 depends on CPU_V7 && SMP
1015 depends on !ARCH_MULTIPLATFORM
1016 help
1017 This option enables the workaround for the 742230 Cortex-A9
1018 (r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction
1019 between two write operations may not ensure the correct visibility
1020 ordering of the two writes. This workaround sets a specific bit in
1021 the diagnostic register of the Cortex-A9 which causes the DMB
1022 instruction to behave as a DSB, ensuring the correct behaviour of
1023 the two writes.
1024
1025config ARM_ERRATA_742231
1026 bool "ARM errata: Incorrect hazard handling in the SCU may lead to data corruption"
1027 depends on CPU_V7 && SMP
1028 depends on !ARCH_MULTIPLATFORM
1029 help
1030 This option enables the workaround for the 742231 Cortex-A9
1031 (r2p0..r2p2) erratum. Under certain conditions, specific to the
1032 Cortex-A9 MPCore micro-architecture, two CPUs working in SMP mode,
1033 accessing some data located in the same cache line, may get corrupted
1034 data due to bad handling of the address hazard when the line gets
1035 replaced from one of the CPUs at the same time as another CPU is
1036 accessing it. This workaround sets specific bits in the diagnostic
1037 register of the Cortex-A9 which reduces the linefill issuing
1038 capabilities of the processor.
1039
1040config ARM_ERRATA_643719
1041 bool "ARM errata: LoUIS bit field in CLIDR register is incorrect"
1042 depends on CPU_V7 && SMP
1043 default y
1044 help
1045 This option enables the workaround for the 643719 Cortex-A9 (prior to
1046 r1p0) erratum. On affected cores the LoUIS bit field of the CLIDR
1047 register returns zero when it should return one. The workaround
1048 corrects this value, ensuring cache maintenance operations which use
1049 it behave as intended and avoiding data corruption.
1050
1051config ARM_ERRATA_720789
1052 bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID"
1053 depends on CPU_V7
1054 help
1055 This option enables the workaround for the 720789 Cortex-A9 (prior to
1056 r2p0) erratum. A faulty ASID can be sent to the other CPUs for the
1057 broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS.
1058 As a consequence of this erratum, some TLB entries which should be
1059 invalidated are not, resulting in an incoherency in the system page
1060 tables. The workaround changes the TLB flushing routines to invalidate
1061 entries regardless of the ASID.
1062
1063config ARM_ERRATA_743622
1064 bool "ARM errata: Faulty hazard checking in the Store Buffer may lead to data corruption"
1065 depends on CPU_V7
1066 depends on !ARCH_MULTIPLATFORM
1067 help
1068 This option enables the workaround for the 743622 Cortex-A9
1069 (r2p*) erratum. Under very rare conditions, a faulty
1070 optimisation in the Cortex-A9 Store Buffer may lead to data
1071 corruption. This workaround sets a specific bit in the diagnostic
1072 register of the Cortex-A9 which disables the Store Buffer
1073 optimisation, preventing the defect from occurring. This has no
1074 visible impact on the overall performance or power consumption of the
1075 processor.
1076
1077config ARM_ERRATA_751472
1078 bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation"
1079 depends on CPU_V7
1080 depends on !ARCH_MULTIPLATFORM
1081 help
1082 This option enables the workaround for the 751472 Cortex-A9 (prior
1083 to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the
1084 completion of a following broadcasted operation if the second
1085 operation is received by a CPU before the ICIALLUIS has completed,
1086 potentially leading to corrupted entries in the cache or TLB.
1087
1088config ARM_ERRATA_754322
1089 bool "ARM errata: possible faulty MMU translations following an ASID switch"
1090 depends on CPU_V7
1091 help
1092 This option enables the workaround for the 754322 Cortex-A9 (r2p*,
1093 r3p*) erratum. A speculative memory access may cause a page table walk
1094 which starts prior to an ASID switch but completes afterwards. This
1095 can populate the micro-TLB with a stale entry which may be hit with
1096 the new ASID. This workaround places two dsb instructions in the mm
1097 switching code so that no page table walks can cross the ASID switch.
1098
1099config ARM_ERRATA_754327
1100 bool "ARM errata: no automatic Store Buffer drain"
1101 depends on CPU_V7 && SMP
1102 help
1103 This option enables the workaround for the 754327 Cortex-A9 (prior to
1104 r2p0) erratum. The Store Buffer does not have any automatic draining
1105 mechanism and therefore a livelock may occur if an external agent
1106 continuously polls a memory location waiting to observe an update.
1107 This workaround defines cpu_relax() as smp_mb(), preventing correctly
1108 written polling loops from denying visibility of updates to memory.
1109
1110config ARM_ERRATA_364296
1111 bool "ARM errata: Possible cache data corruption with hit-under-miss enabled"
1112 depends on CPU_V6
1113 help
1114 This options enables the workaround for the 364296 ARM1136
1115 r0p2 erratum (possible cache data corruption with
1116 hit-under-miss enabled). It sets the undocumented bit 31 in
1117 the auxiliary control register and the FI bit in the control
1118 register, thus disabling hit-under-miss without putting the
1119 processor into full low interrupt latency mode. ARM11MPCore
1120 is not affected.
1121
1122config ARM_ERRATA_764369
1123 bool "ARM errata: Data cache line maintenance operation by MVA may not succeed"
1124 depends on CPU_V7 && SMP
1125 help
1126 This option enables the workaround for erratum 764369
1127 affecting Cortex-A9 MPCore with two or more processors (all
1128 current revisions). Under certain timing circumstances, a data
1129 cache line maintenance operation by MVA targeting an Inner
1130 Shareable memory region may fail to proceed up to either the
1131 Point of Coherency or to the Point of Unification of the
1132 system. This workaround adds a DSB instruction before the
1133 relevant cache maintenance functions and sets a specific bit
1134 in the diagnostic control register of the SCU.
1135
1136config ARM_ERRATA_775420
1137 bool "ARM errata: A data cache maintenance operation which aborts, might lead to deadlock"
1138 depends on CPU_V7
1139 help
1140 This option enables the workaround for the 775420 Cortex-A9 (r2p2,
1141 r2p6,r2p8,r2p10,r3p0) erratum. In case a date cache maintenance
1142 operation aborts with MMU exception, it might cause the processor
1143 to deadlock. This workaround puts DSB before executing ISB if
1144 an abort may occur on cache maintenance.
1145
1146config ARM_ERRATA_798181
1147 bool "ARM errata: TLBI/DSB failure on Cortex-A15"
1148 depends on CPU_V7 && SMP
1149 help
1150 On Cortex-A15 (r0p0..r3p2) the TLBI*IS/DSB operations are not
1151 adequately shooting down all use of the old entries. This
1152 option enables the Linux kernel workaround for this erratum
1153 which sends an IPI to the CPUs that are running the same ASID
1154 as the one being invalidated.
1155
1156config ARM_ERRATA_773022
1157 bool "ARM errata: incorrect instructions may be executed from loop buffer"
1158 depends on CPU_V7
1159 help
1160 This option enables the workaround for the 773022 Cortex-A15
1161 (up to r0p4) erratum. In certain rare sequences of code, the
1162 loop buffer may deliver incorrect instructions. This
1163 workaround disables the loop buffer to avoid the erratum.
1164
1165config ARM_ERRATA_818325_852422
1166 bool "ARM errata: A12: some seqs of opposed cond code instrs => deadlock or corruption"
1167 depends on CPU_V7
1168 help
1169 This option enables the workaround for:
1170 - Cortex-A12 818325: Execution of an UNPREDICTABLE STR or STM
1171 instruction might deadlock. Fixed in r0p1.
1172 - Cortex-A12 852422: Execution of a sequence of instructions might
1173 lead to either a data corruption or a CPU deadlock. Not fixed in
1174 any Cortex-A12 cores yet.
1175 This workaround for all both errata involves setting bit[12] of the
1176 Feature Register. This bit disables an optimisation applied to a
1177 sequence of 2 instructions that use opposing condition codes.
1178
1179config ARM_ERRATA_821420
1180 bool "ARM errata: A12: sequence of VMOV to core registers might lead to a dead lock"
1181 depends on CPU_V7
1182 help
1183 This option enables the workaround for the 821420 Cortex-A12
1184 (all revs) erratum. In very rare timing conditions, a sequence
1185 of VMOV to Core registers instructions, for which the second
1186 one is in the shadow of a branch or abort, can lead to a
1187 deadlock when the VMOV instructions are issued out-of-order.
1188
1189config ARM_ERRATA_825619
1190 bool "ARM errata: A12: DMB NSHST/ISHST mixed ... might cause deadlock"
1191 depends on CPU_V7
1192 help
1193 This option enables the workaround for the 825619 Cortex-A12
1194 (all revs) erratum. Within rare timing constraints, executing a
1195 DMB NSHST or DMB ISHST instruction followed by a mix of Cacheable
1196 and Device/Strongly-Ordered loads and stores might cause deadlock
1197
1198config ARM_ERRATA_852421
1199 bool "ARM errata: A17: DMB ST might fail to create order between stores"
1200 depends on CPU_V7
1201 help
1202 This option enables the workaround for the 852421 Cortex-A17
1203 (r1p0, r1p1, r1p2) erratum. Under very rare timing conditions,
1204 execution of a DMB ST instruction might fail to properly order
1205 stores from GroupA and stores from GroupB.
1206
1207config ARM_ERRATA_852423
1208 bool "ARM errata: A17: some seqs of opposed cond code instrs => deadlock or corruption"
1209 depends on CPU_V7
1210 help
1211 This option enables the workaround for:
1212 - Cortex-A17 852423: Execution of a sequence of instructions might
1213 lead to either a data corruption or a CPU deadlock. Not fixed in
1214 any Cortex-A17 cores yet.
1215 This is identical to Cortex-A12 erratum 852422. It is a separate
1216 config option from the A12 erratum due to the way errata are checked
1217 for and handled.
1218
1219endmenu
1220
1221source "arch/arm/common/Kconfig"
1222
1223menu "Bus support"
1224
1225config ISA
1226 bool
1227 help
1228 Find out whether you have ISA slots on your motherboard. ISA is the
1229 name of a bus system, i.e. the way the CPU talks to the other stuff
1230 inside your box. Other bus systems are PCI, EISA, MicroChannel
1231 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1232 newer boards don't support it. If you have ISA, say Y, otherwise N.
1233
1234# Select ISA DMA controller support
1235config ISA_DMA
1236 bool
1237 select ISA_DMA_API
1238
1239# Select ISA DMA interface
1240config ISA_DMA_API
1241 bool
1242
1243config PCI
1244 bool "PCI support" if MIGHT_HAVE_PCI
1245 help
1246 Find out whether you have a PCI motherboard. PCI is the name of a
1247 bus system, i.e. the way the CPU talks to the other stuff inside
1248 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1249 VESA. If you have PCI, say Y, otherwise N.
1250
1251config PCI_DOMAINS
1252 bool
1253 depends on PCI
1254
1255config PCI_DOMAINS_GENERIC
1256 def_bool PCI_DOMAINS
1257
1258config PCI_NANOENGINE
1259 bool "BSE nanoEngine PCI support"
1260 depends on SA1100_NANOENGINE
1261 help
1262 Enable PCI on the BSE nanoEngine board.
1263
1264config PCI_SYSCALL
1265 def_bool PCI
1266
1267config PCI_HOST_ITE8152
1268 bool
1269 depends on PCI && MACH_ARMCORE
1270 default y
1271 select DMABOUNCE
1272
1273source "drivers/pci/Kconfig"
1274
1275source "drivers/pcmcia/Kconfig"
1276
1277endmenu
1278
1279menu "Kernel Features"
1280
1281config HAVE_SMP
1282 bool
1283 help
1284 This option should be selected by machines which have an SMP-
1285 capable CPU.
1286
1287 The only effect of this option is to make the SMP-related
1288 options available to the user for configuration.
1289
1290config SMP
1291 bool "Symmetric Multi-Processing"
1292 depends on CPU_V6K || CPU_V7
1293 depends on GENERIC_CLOCKEVENTS
1294 depends on HAVE_SMP
1295 depends on MMU || ARM_MPU
1296 select IRQ_WORK
1297 help
1298 This enables support for systems with more than one CPU. If you have
1299 a system with only one CPU, say N. If you have a system with more
1300 than one CPU, say Y.
1301
1302 If you say N here, the kernel will run on uni- and multiprocessor
1303 machines, but will use only one CPU of a multiprocessor machine. If
1304 you say Y here, the kernel will run on many, but not all,
1305 uniprocessor machines. On a uniprocessor machine, the kernel
1306 will run faster if you say N here.
1307
1308 See also <file:Documentation/x86/i386/IO-APIC.txt>,
1309 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
1310 <http://tldp.org/HOWTO/SMP-HOWTO.html>.
1311
1312 If you don't know what to do here, say N.
1313
1314config SMP_ON_UP
1315 bool "Allow booting SMP kernel on uniprocessor systems"
1316 depends on SMP && !XIP_KERNEL && MMU
1317 default y
1318 help
1319 SMP kernels contain instructions which fail on non-SMP processors.
1320 Enabling this option allows the kernel to modify itself to make
1321 these instructions safe. Disabling it allows about 1K of space
1322 savings.
1323
1324 If you don't know what to do here, say Y.
1325
1326config ARM_CPU_TOPOLOGY
1327 bool "Support cpu topology definition"
1328 depends on SMP && CPU_V7
1329 default y
1330 help
1331 Support ARM cpu topology definition. The MPIDR register defines
1332 affinity between processors which is then used to describe the cpu
1333 topology of an ARM System.
1334
1335config SCHED_MC
1336 bool "Multi-core scheduler support"
1337 depends on ARM_CPU_TOPOLOGY
1338 help
1339 Multi-core scheduler support improves the CPU scheduler's decision
1340 making when dealing with multi-core CPU chips at a cost of slightly
1341 increased overhead in some places. If unsure say N here.
1342
1343config SCHED_SMT
1344 bool "SMT scheduler support"
1345 depends on ARM_CPU_TOPOLOGY
1346 help
1347 Improves the CPU scheduler's decision making when dealing with
1348 MultiThreading at a cost of slightly increased overhead in some
1349 places. If unsure say N here.
1350
1351config HAVE_ARM_SCU
1352 bool
1353 help
1354 This option enables support for the ARM system coherency unit
1355
1356config HAVE_ARM_ARCH_TIMER
1357 bool "Architected timer support"
1358 depends on CPU_V7
1359 select ARM_ARCH_TIMER
1360 select GENERIC_CLOCKEVENTS
1361 help
1362 This option enables support for the ARM architected timer
1363
1364config HAVE_ARM_TWD
1365 bool
1366 select TIMER_OF if OF
1367 help
1368 This options enables support for the ARM timer and watchdog unit
1369
1370config MCPM
1371 bool "Multi-Cluster Power Management"
1372 depends on CPU_V7 && SMP
1373 help
1374 This option provides the common power management infrastructure
1375 for (multi-)cluster based systems, such as big.LITTLE based
1376 systems.
1377
1378config MCPM_QUAD_CLUSTER
1379 bool
1380 depends on MCPM
1381 help
1382 To avoid wasting resources unnecessarily, MCPM only supports up
1383 to 2 clusters by default.
1384 Platforms with 3 or 4 clusters that use MCPM must select this
1385 option to allow the additional clusters to be managed.
1386
1387config BIG_LITTLE
1388 bool "big.LITTLE support (Experimental)"
1389 depends on CPU_V7 && SMP
1390 select MCPM
1391 help
1392 This option enables support selections for the big.LITTLE
1393 system architecture.
1394
1395config BL_SWITCHER
1396 bool "big.LITTLE switcher support"
1397 depends on BIG_LITTLE && MCPM && HOTPLUG_CPU && ARM_GIC
1398 select CPU_PM
1399 help
1400 The big.LITTLE "switcher" provides the core functionality to
1401 transparently handle transition between a cluster of A15's
1402 and a cluster of A7's in a big.LITTLE system.
1403
1404config BL_SWITCHER_DUMMY_IF
1405 tristate "Simple big.LITTLE switcher user interface"
1406 depends on BL_SWITCHER && DEBUG_KERNEL
1407 help
1408 This is a simple and dummy char dev interface to control
1409 the big.LITTLE switcher core code. It is meant for
1410 debugging purposes only.
1411
1412choice
1413 prompt "Memory split"
1414 depends on MMU
1415 default VMSPLIT_3G
1416 help
1417 Select the desired split between kernel and user memory.
1418
1419 If you are not absolutely sure what you are doing, leave this
1420 option alone!
1421
1422 config VMSPLIT_3G
1423 bool "3G/1G user/kernel split"
1424 config VMSPLIT_3G_OPT
1425 depends on !ARM_LPAE
1426 bool "3G/1G user/kernel split (for full 1G low memory)"
1427 config VMSPLIT_2G
1428 bool "2G/2G user/kernel split"
1429 config VMSPLIT_1G
1430 bool "1G/3G user/kernel split"
1431endchoice
1432
1433config PAGE_OFFSET
1434 hex
1435 default PHYS_OFFSET if !MMU
1436 default 0x40000000 if VMSPLIT_1G
1437 default 0x80000000 if VMSPLIT_2G
1438 default 0xB0000000 if VMSPLIT_3G_OPT
1439 default 0xC0000000
1440
1441config NR_CPUS
1442 int "Maximum number of CPUs (2-32)"
1443 range 2 32
1444 depends on SMP
1445 default "4"
1446
1447config HOTPLUG_CPU
1448 bool "Support for hot-pluggable CPUs"
1449 depends on SMP
1450 select GENERIC_IRQ_MIGRATION
1451 help
1452 Say Y here to experiment with turning CPUs off and on. CPUs
1453 can be controlled through /sys/devices/system/cpu.
1454
1455config ARM_PSCI
1456 bool "Support for the ARM Power State Coordination Interface (PSCI)"
1457 depends on HAVE_ARM_SMCCC
1458 select ARM_PSCI_FW
1459 help
1460 Say Y here if you want Linux to communicate with system firmware
1461 implementing the PSCI specification for CPU-centric power
1462 management operations described in ARM document number ARM DEN
1463 0022A ("Power State Coordination Interface System Software on
1464 ARM processors").
1465
1466# The GPIO number here must be sorted by descending number. In case of
1467# a multiplatform kernel, we just want the highest value required by the
1468# selected platforms.
1469config ARCH_NR_GPIO
1470 int
1471 default 2048 if ARCH_SOCFPGA
1472 default 1024 if ARCH_BRCMSTB || ARCH_SHMOBILE || ARCH_TEGRA || \
1473 ARCH_ZYNQ
1474 default 512 if ARCH_EXYNOS || ARCH_KEYSTONE || SOC_OMAP5 || \
1475 SOC_DRA7XX || ARCH_S3C24XX || ARCH_S3C64XX || ARCH_S5PV210
1476 default 416 if ARCH_SUNXI
1477 default 392 if ARCH_U8500
1478 default 352 if ARCH_VT8500
1479 default 288 if ARCH_ROCKCHIP
1480 default 264 if MACH_H4700
1481 default 0
1482 help
1483 Maximum number of GPIOs in the system.
1484
1485 If unsure, leave the default value.
1486
1487source kernel/Kconfig.preempt
1488
1489config HZ_FIXED
1490 int
1491 default 200 if ARCH_EBSA110
1492 default 128 if SOC_AT91RM9200
1493 default 0
1494
1495choice
1496 depends on HZ_FIXED = 0
1497 prompt "Timer frequency"
1498
1499config HZ_100
1500 bool "100 Hz"
1501
1502config HZ_200
1503 bool "200 Hz"
1504
1505config HZ_250
1506 bool "250 Hz"
1507
1508config HZ_300
1509 bool "300 Hz"
1510
1511config HZ_500
1512 bool "500 Hz"
1513
1514config HZ_1000
1515 bool "1000 Hz"
1516
1517endchoice
1518
1519config HZ
1520 int
1521 default HZ_FIXED if HZ_FIXED != 0
1522 default 100 if HZ_100
1523 default 200 if HZ_200
1524 default 250 if HZ_250
1525 default 300 if HZ_300
1526 default 500 if HZ_500
1527 default 1000
1528
1529config SCHED_HRTICK
1530 def_bool HIGH_RES_TIMERS
1531
1532config THUMB2_KERNEL
1533 bool "Compile the kernel in Thumb-2 mode" if !CPU_THUMBONLY
1534 depends on (CPU_V7 || CPU_V7M) && !CPU_V6 && !CPU_V6K
1535 default y if CPU_THUMBONLY
1536 select ARM_UNWIND
1537 help
1538 By enabling this option, the kernel will be compiled in
1539 Thumb-2 mode.
1540
1541 If unsure, say N.
1542
1543config THUMB2_AVOID_R_ARM_THM_JUMP11
1544 bool "Work around buggy Thumb-2 short branch relocations in gas"
1545 depends on THUMB2_KERNEL && MODULES
1546 default y
1547 help
1548 Various binutils versions can resolve Thumb-2 branches to
1549 locally-defined, preemptible global symbols as short-range "b.n"
1550 branch instructions.
1551
1552 This is a problem, because there's no guarantee the final
1553 destination of the symbol, or any candidate locations for a
1554 trampoline, are within range of the branch. For this reason, the
1555 kernel does not support fixing up the R_ARM_THM_JUMP11 (102)
1556 relocation in modules at all, and it makes little sense to add
1557 support.
1558
1559 The symptom is that the kernel fails with an "unsupported
1560 relocation" error when loading some modules.
1561
1562 Until fixed tools are available, passing
1563 -fno-optimize-sibling-calls to gcc should prevent gcc generating
1564 code which hits this problem, at the cost of a bit of extra runtime
1565 stack usage in some cases.
1566
1567 The problem is described in more detail at:
1568 https://bugs.launchpad.net/binutils-linaro/+bug/725126
1569
1570 Only Thumb-2 kernels are affected.
1571
1572 Unless you are sure your tools don't have this problem, say Y.
1573
1574config ARM_PATCH_IDIV
1575 bool "Runtime patch udiv/sdiv instructions into __aeabi_{u}idiv()"
1576 depends on CPU_32v7 && !XIP_KERNEL
1577 default y
1578 help
1579 The ARM compiler inserts calls to __aeabi_idiv() and
1580 __aeabi_uidiv() when it needs to perform division on signed
1581 and unsigned integers. Some v7 CPUs have support for the sdiv
1582 and udiv instructions that can be used to implement those
1583 functions.
1584
1585 Enabling this option allows the kernel to modify itself to
1586 replace the first two instructions of these library functions
1587 with the sdiv or udiv plus "bx lr" instructions when the CPU
1588 it is running on supports them. Typically this will be faster
1589 and less power intensive than running the original library
1590 code to do integer division.
1591
1592config AEABI
1593 bool "Use the ARM EABI to compile the kernel" if !CPU_V7 && !CPU_V7M && !CPU_V6 && !CPU_V6K
1594 default CPU_V7 || CPU_V7M || CPU_V6 || CPU_V6K
1595 help
1596 This option allows for the kernel to be compiled using the latest
1597 ARM ABI (aka EABI). This is only useful if you are using a user
1598 space environment that is also compiled with EABI.
1599
1600 Since there are major incompatibilities between the legacy ABI and
1601 EABI, especially with regard to structure member alignment, this
1602 option also changes the kernel syscall calling convention to
1603 disambiguate both ABIs and allow for backward compatibility support
1604 (selected with CONFIG_OABI_COMPAT).
1605
1606 To use this you need GCC version 4.0.0 or later.
1607
1608config OABI_COMPAT
1609 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1610 depends on AEABI && !THUMB2_KERNEL
1611 help
1612 This option preserves the old syscall interface along with the
1613 new (ARM EABI) one. It also provides a compatibility layer to
1614 intercept syscalls that have structure arguments which layout
1615 in memory differs between the legacy ABI and the new ARM EABI
1616 (only for non "thumb" binaries). This option adds a tiny
1617 overhead to all syscalls and produces a slightly larger kernel.
1618
1619 The seccomp filter system will not be available when this is
1620 selected, since there is no way yet to sensibly distinguish
1621 between calling conventions during filtering.
1622
1623 If you know you'll be using only pure EABI user space then you
1624 can say N here. If this option is not selected and you attempt
1625 to execute a legacy ABI binary then the result will be
1626 UNPREDICTABLE (in fact it can be predicted that it won't work
1627 at all). If in doubt say N.
1628
1629config ARCH_HAS_HOLES_MEMORYMODEL
1630 bool
1631
1632config ARCH_SPARSEMEM_ENABLE
1633 bool
1634
1635config ARCH_SPARSEMEM_DEFAULT
1636 def_bool ARCH_SPARSEMEM_ENABLE
1637
1638config ARCH_SELECT_MEMORY_MODEL
1639 def_bool ARCH_SPARSEMEM_ENABLE
1640
1641config HAVE_ARCH_PFN_VALID
1642 def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM
1643
1644config HAVE_GENERIC_GUP
1645 def_bool y
1646 depends on ARM_LPAE
1647
1648config HIGHMEM
1649 bool "High Memory Support"
1650 depends on MMU
1651 help
1652 The address space of ARM processors is only 4 Gigabytes large
1653 and it has to accommodate user address space, kernel address
1654 space as well as some memory mapped IO. That means that, if you
1655 have a large amount of physical memory and/or IO, not all of the
1656 memory can be "permanently mapped" by the kernel. The physical
1657 memory that is not permanently mapped is called "high memory".
1658
1659 Depending on the selected kernel/user memory split, minimum
1660 vmalloc space and actual amount of RAM, you may not need this
1661 option which should result in a slightly faster kernel.
1662
1663 If unsure, say n.
1664
1665config HIGHPTE
1666 bool "Allocate 2nd-level pagetables from highmem" if EXPERT
1667 depends on HIGHMEM
1668 default y
1669 help
1670 The VM uses one page of physical memory for each page table.
1671 For systems with a lot of processes, this can use a lot of
1672 precious low memory, eventually leading to low memory being
1673 consumed by page tables. Setting this option will allow
1674 user-space 2nd level page tables to reside in high memory.
1675
1676config CPU_SW_DOMAIN_PAN
1677 bool "Enable use of CPU domains to implement privileged no-access"
1678 depends on MMU && !ARM_LPAE
1679 default y
1680 help
1681 Increase kernel security by ensuring that normal kernel accesses
1682 are unable to access userspace addresses. This can help prevent
1683 use-after-free bugs becoming an exploitable privilege escalation
1684 by ensuring that magic values (such as LIST_POISON) will always
1685 fault when dereferenced.
1686
1687 CPUs with low-vector mappings use a best-efforts implementation.
1688 Their lower 1MB needs to remain accessible for the vectors, but
1689 the remainder of userspace will become appropriately inaccessible.
1690
1691config HW_PERF_EVENTS
1692 def_bool y
1693 depends on ARM_PMU
1694
1695config SYS_SUPPORTS_HUGETLBFS
1696 def_bool y
1697 depends on ARM_LPAE
1698
1699config HAVE_ARCH_TRANSPARENT_HUGEPAGE
1700 def_bool y
1701 depends on ARM_LPAE
1702
1703config ARCH_WANT_GENERAL_HUGETLB
1704 def_bool y
1705
1706config ARM_MODULE_PLTS
1707 bool "Use PLTs to allow module memory to spill over into vmalloc area"
1708 depends on MODULES
1709 help
1710 Allocate PLTs when loading modules so that jumps and calls whose
1711 targets are too far away for their relative offsets to be encoded
1712 in the instructions themselves can be bounced via veneers in the
1713 module's PLT. This allows modules to be allocated in the generic
1714 vmalloc area after the dedicated module memory area has been
1715 exhausted. The modules will use slightly more memory, but after
1716 rounding up to page size, the actual memory footprint is usually
1717 the same.
1718
1719 Say y if you are getting out of memory errors while loading modules
1720
1721source "mm/Kconfig"
1722
1723config FORCE_MAX_ZONEORDER
1724 int "Maximum zone order"
1725 default "12" if SOC_AM33XX
1726 default "9" if SA1111 || ARCH_EFM32
1727 default "11"
1728 help
1729 The kernel memory allocator divides physically contiguous memory
1730 blocks into "zones", where each zone is a power of two number of
1731 pages. This option selects the largest power of two that the kernel
1732 keeps in the memory allocator. If you need to allocate very large
1733 blocks of physically contiguous memory, then you may need to
1734 increase this value.
1735
1736 This config option is actually maximum order plus one. For example,
1737 a value of 11 means that the largest free memory block is 2^10 pages.
1738
1739config ALIGNMENT_TRAP
1740 bool
1741 depends on CPU_CP15_MMU
1742 default y if !ARCH_EBSA110
1743 select HAVE_PROC_CPU if PROC_FS
1744 help
1745 ARM processors cannot fetch/store information which is not
1746 naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1747 address divisible by 4. On 32-bit ARM processors, these non-aligned
1748 fetch/store instructions will be emulated in software if you say
1749 here, which has a severe performance impact. This is necessary for
1750 correct operation of some network protocols. With an IP-only
1751 configuration it is safe to say N, otherwise say Y.
1752
1753config UACCESS_WITH_MEMCPY
1754 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user()"
1755 depends on MMU
1756 default y if CPU_FEROCEON
1757 help
1758 Implement faster copy_to_user and clear_user methods for CPU
1759 cores where a 8-word STM instruction give significantly higher
1760 memory write throughput than a sequence of individual 32bit stores.
1761
1762 A possible side effect is a slight increase in scheduling latency
1763 between threads sharing the same address space if they invoke
1764 such copy operations with large buffers.
1765
1766 However, if the CPU data cache is using a write-allocate mode,
1767 this option is unlikely to provide any performance gain.
1768
1769config SECCOMP
1770 bool
1771 prompt "Enable seccomp to safely compute untrusted bytecode"
1772 ---help---
1773 This kernel feature is useful for number crunching applications
1774 that may need to compute untrusted bytecode during their
1775 execution. By using pipes or other transports made available to
1776 the process as file descriptors supporting the read/write
1777 syscalls, it's possible to isolate those applications in
1778 their own address space using seccomp. Once seccomp is
1779 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1780 and the task is only allowed to execute a few safe syscalls
1781 defined by each seccomp mode.
1782
1783config SWIOTLB
1784 def_bool y
1785
1786config IOMMU_HELPER
1787 def_bool SWIOTLB
1788
1789config PARAVIRT
1790 bool "Enable paravirtualization code"
1791 help
1792 This changes the kernel so it can modify itself when it is run
1793 under a hypervisor, potentially improving performance significantly
1794 over full virtualization.
1795
1796config PARAVIRT_TIME_ACCOUNTING
1797 bool "Paravirtual steal time accounting"
1798 select PARAVIRT
1799 default n
1800 help
1801 Select this option to enable fine granularity task steal time
1802 accounting. Time spent executing other tasks in parallel with
1803 the current vCPU is discounted from the vCPU power. To account for
1804 that, there can be a small performance impact.
1805
1806 If in doubt, say N here.
1807
1808config XEN_DOM0
1809 def_bool y
1810 depends on XEN
1811
1812config XEN
1813 bool "Xen guest support on ARM"
1814 depends on ARM && AEABI && OF
1815 depends on CPU_V7 && !CPU_V6
1816 depends on !GENERIC_ATOMIC64
1817 depends on MMU
1818 select ARCH_DMA_ADDR_T_64BIT
1819 select ARM_PSCI
1820 select SWIOTLB_XEN
1821 select PARAVIRT
1822 help
1823 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
1824
1825config ARM_FLUSH_CONSOLE_ON_RESTART
1826 bool "Force flush the console on restart"
1827 help
1828 If the console is locked while the system is rebooted, the messages
1829 in the temporary logbuffer would not have propogated to all the
1830 console drivers. This option forces the console lock to be
1831 released if it failed to be acquired, which will cause all the
1832 pending messages to be flushed.
1833
1834endmenu
1835
1836menu "Boot options"
1837
1838config USE_OF
1839 bool "Flattened Device Tree support"
1840 select IRQ_DOMAIN
1841 select OF
1842 help
1843 Include support for flattened device tree machine descriptions.
1844
1845config ATAGS
1846 bool "Support for the traditional ATAGS boot data passing" if USE_OF
1847 default y
1848 help
1849 This is the traditional way of passing data to the kernel at boot
1850 time. If you are solely relying on the flattened device tree (or
1851 the ARM_ATAG_DTB_COMPAT option) then you may unselect this option
1852 to remove ATAGS support from your kernel binary. If unsure,
1853 leave this to y.
1854
1855config DEPRECATED_PARAM_STRUCT
1856 bool "Provide old way to pass kernel parameters"
1857 depends on ATAGS
1858 help
1859 This was deprecated in 2001 and announced to live on for 5 years.
1860 Some old boot loaders still use this way.
1861
1862config BUILD_ARM_APPENDED_DTB_IMAGE
1863 bool "Build a concatenated zImage/dtb by default"
1864 depends on OF
1865 help
1866 Enabling this option will cause a concatenated zImage and list of
1867 DTBs to be built by default (instead of a standalone zImage.)
1868 The image will built in arch/arm/boot/zImage-dtb
1869
1870config BUILD_ARM_APPENDED_DTB_IMAGE_NAMES
1871 string "Default dtb names"
1872 depends on BUILD_ARM_APPENDED_DTB_IMAGE
1873 help
1874 Space separated list of names of dtbs to append when
1875 building a concatenated zImage-dtb.
1876
1877# Compressed boot loader in ROM. Yes, we really want to ask about
1878# TEXT and BSS so we preserve their values in the config files.
1879config ZBOOT_ROM_TEXT
1880 hex "Compressed ROM boot loader base address"
1881 default "0"
1882 help
1883 The physical address at which the ROM-able zImage is to be
1884 placed in the target. Platforms which normally make use of
1885 ROM-able zImage formats normally set this to a suitable
1886 value in their defconfig file.
1887
1888 If ZBOOT_ROM is not enabled, this has no effect.
1889
1890config ZBOOT_ROM_BSS
1891 hex "Compressed ROM boot loader BSS address"
1892 default "0"
1893 help
1894 The base address of an area of read/write memory in the target
1895 for the ROM-able zImage which must be available while the
1896 decompressor is running. It must be large enough to hold the
1897 entire decompressed kernel plus an additional 128 KiB.
1898 Platforms which normally make use of ROM-able zImage formats
1899 normally set this to a suitable value in their defconfig file.
1900
1901 If ZBOOT_ROM is not enabled, this has no effect.
1902
1903config ZBOOT_ROM
1904 bool "Compressed boot loader in ROM/flash"
1905 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1906 depends on !ARM_APPENDED_DTB && !XIP_KERNEL && !AUTO_ZRELADDR
1907 help
1908 Say Y here if you intend to execute your compressed kernel image
1909 (zImage) directly from ROM or flash. If unsure, say N.
1910
1911config ARM_APPENDED_DTB
1912 bool "Use appended device tree blob to zImage (EXPERIMENTAL)"
1913 depends on OF
1914 help
1915 With this option, the boot code will look for a device tree binary
1916 (DTB) appended to zImage
1917 (e.g. cat zImage <filename>.dtb > zImage_w_dtb).
1918
1919 This is meant as a backward compatibility convenience for those
1920 systems with a bootloader that can't be upgraded to accommodate
1921 the documented boot protocol using a device tree.
1922
1923 Beware that there is very little in terms of protection against
1924 this option being confused by leftover garbage in memory that might
1925 look like a DTB header after a reboot if no actual DTB is appended
1926 to zImage. Do not leave this option active in a production kernel
1927 if you don't intend to always append a DTB. Proper passing of the
1928 location into r2 of a bootloader provided DTB is always preferable
1929 to this option.
1930
1931config ARM_ATAG_DTB_COMPAT
1932 bool "Supplement the appended DTB with traditional ATAG information"
1933 depends on ARM_APPENDED_DTB
1934 help
1935 Some old bootloaders can't be updated to a DTB capable one, yet
1936 they provide ATAGs with memory configuration, the ramdisk address,
1937 the kernel cmdline string, etc. Such information is dynamically
1938 provided by the bootloader and can't always be stored in a static
1939 DTB. To allow a device tree enabled kernel to be used with such
1940 bootloaders, this option allows zImage to extract the information
1941 from the ATAG list and store it at run time into the appended DTB.
1942
1943choice
1944 prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT
1945 default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1946
1947config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1948 bool "Use bootloader kernel arguments if available"
1949 help
1950 Uses the command-line options passed by the boot loader instead of
1951 the device tree bootargs property. If the boot loader doesn't provide
1952 any, the device tree bootargs property will be used.
1953
1954config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND
1955 bool "Extend with bootloader kernel arguments"
1956 help
1957 The command-line arguments provided by the boot loader will be
1958 appended to the the device tree bootargs property.
1959
1960endchoice
1961
1962config CMDLINE
1963 string "Default kernel command string"
1964 default ""
1965 help
1966 On some architectures (EBSA110 and CATS), there is currently no way
1967 for the boot loader to pass arguments to the kernel. For these
1968 architectures, you should supply some command-line options at build
1969 time by entering them here. As a minimum, you should specify the
1970 memory size and the root device (e.g., mem=64M root=/dev/nfs).
1971
1972choice
1973 prompt "Kernel command line type" if CMDLINE != ""
1974 default CMDLINE_FROM_BOOTLOADER
1975 depends on ATAGS
1976
1977config CMDLINE_FROM_BOOTLOADER
1978 bool "Use bootloader kernel arguments if available"
1979 help
1980 Uses the command-line options passed by the boot loader. If
1981 the boot loader doesn't provide any, the default kernel command
1982 string provided in CMDLINE will be used.
1983
1984config CMDLINE_EXTEND
1985 bool "Extend bootloader kernel arguments"
1986 help
1987 The command-line arguments provided by the boot loader will be
1988 appended to the default kernel command string.
1989
1990config CMDLINE_FORCE
1991 bool "Always use the default kernel command string"
1992 help
1993 Always use the default kernel command string, even if the boot
1994 loader passes other arguments to the kernel.
1995 This is useful if you cannot or don't want to change the
1996 command-line options your boot loader passes to the kernel.
1997endchoice
1998
1999config XIP_KERNEL
2000 bool "Kernel Execute-In-Place from ROM"
2001 depends on !ARM_LPAE && !ARCH_MULTIPLATFORM
2002 help
2003 Execute-In-Place allows the kernel to run from non-volatile storage
2004 directly addressable by the CPU, such as NOR flash. This saves RAM
2005 space since the text section of the kernel is not loaded from flash
2006 to RAM. Read-write sections, such as the data section and stack,
2007 are still copied to RAM. The XIP kernel is not compressed since
2008 it has to run directly from flash, so it will take more space to
2009 store it. The flash address used to link the kernel object files,
2010 and for storing it, is configuration dependent. Therefore, if you
2011 say Y here, you must know the proper physical address where to
2012 store the kernel image depending on your own flash memory usage.
2013
2014 Also note that the make target becomes "make xipImage" rather than
2015 "make zImage" or "make Image". The final kernel binary to put in
2016 ROM memory will be arch/arm/boot/xipImage.
2017
2018 If unsure, say N.
2019
2020config XIP_PHYS_ADDR
2021 hex "XIP Kernel Physical Location"
2022 depends on XIP_KERNEL
2023 default "0x00080000"
2024 help
2025 This is the physical address in your flash memory the kernel will
2026 be linked for and stored to. This address is dependent on your
2027 own flash usage.
2028
2029config KEXEC
2030 bool "Kexec system call (EXPERIMENTAL)"
2031 depends on (!SMP || PM_SLEEP_SMP)
2032 depends on MMU
2033 select KEXEC_CORE
2034 help
2035 kexec is a system call that implements the ability to shutdown your
2036 current kernel, and to start another kernel. It is like a reboot
2037 but it is independent of the system firmware. And like a reboot
2038 you can start any kernel with it, not just Linux.
2039
2040 It is an ongoing process to be certain the hardware in a machine
2041 is properly shutdown, so do not be surprised if this code does not
2042 initially work for you.
2043
2044config ATAGS_PROC
2045 bool "Export atags in procfs"
2046 depends on ATAGS && 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 help
2055 Generate crash dump after being started by kexec. This should
2056 be normally only set in special crash dump kernels which are
2057 loaded in the main kernel with kexec-tools into a specially
2058 reserved region and then later executed after a crash by
2059 kdump/kexec. The crash dump kernel must be compiled to a
2060 memory address not used by the main kernel
2061
2062 For more details see Documentation/kdump/kdump.txt
2063
2064config AUTO_ZRELADDR
2065 bool "Auto calculation of the decompressed kernel image address"
2066 help
2067 ZRELADDR is the physical address where the decompressed kernel
2068 image will be placed. If AUTO_ZRELADDR is selected, the address
2069 will be determined at run-time by masking the current IP with
2070 0xf8000000. This assumes the zImage being placed in the first 128MB
2071 from start of memory.
2072
2073config EFI_STUB
2074 bool
2075
2076config EFI
2077 bool "UEFI runtime support"
2078 depends on OF && !CPU_BIG_ENDIAN && MMU && AUTO_ZRELADDR && !XIP_KERNEL
2079 select UCS2_STRING
2080 select EFI_PARAMS_FROM_FDT
2081 select EFI_STUB
2082 select EFI_ARMSTUB
2083 select EFI_RUNTIME_WRAPPERS
2084 ---help---
2085 This option provides support for runtime services provided
2086 by UEFI firmware (such as non-volatile variables, realtime
2087 clock, and platform reset). A UEFI stub is also provided to
2088 allow the kernel to be booted as an EFI application. This
2089 is only useful for kernels that may run on systems that have
2090 UEFI firmware.
2091
2092config DMI
2093 bool "Enable support for SMBIOS (DMI) tables"
2094 depends on EFI
2095 default y
2096 help
2097 This enables SMBIOS/DMI feature for systems.
2098
2099 This option is only useful on systems that have UEFI firmware.
2100 However, even with this option, the resultant kernel should
2101 continue to boot on existing non-UEFI platforms.
2102
2103 NOTE: This does *NOT* enable or encourage the use of DMI quirks,
2104 i.e., the the practice of identifying the platform via DMI to
2105 decide whether certain workarounds for buggy hardware and/or
2106 firmware need to be enabled. This would require the DMI subsystem
2107 to be enabled much earlier than we do on ARM, which is non-trivial.
2108
2109endmenu
2110
2111menu "CPU Power Management"
2112
2113source "drivers/cpufreq/Kconfig"
2114
2115source "drivers/cpuidle/Kconfig"
2116
2117endmenu
2118
2119menu "Floating point emulation"
2120
2121comment "At least one emulation must be selected"
2122
2123config FPE_NWFPE
2124 bool "NWFPE math emulation"
2125 depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL
2126 ---help---
2127 Say Y to include the NWFPE floating point emulator in the kernel.
2128 This is necessary to run most binaries. Linux does not currently
2129 support floating point hardware so you need to say Y here even if
2130 your machine has an FPA or floating point co-processor podule.
2131
2132 You may say N here if you are going to load the Acorn FPEmulator
2133 early in the bootup.
2134
2135config FPE_NWFPE_XP
2136 bool "Support extended precision"
2137 depends on FPE_NWFPE
2138 help
2139 Say Y to include 80-bit support in the kernel floating-point
2140 emulator. Otherwise, only 32 and 64-bit support is compiled in.
2141 Note that gcc does not generate 80-bit operations by default,
2142 so in most cases this option only enlarges the size of the
2143 floating point emulator without any good reason.
2144
2145 You almost surely want to say N here.
2146
2147config FPE_FASTFPE
2148 bool "FastFPE math emulation (EXPERIMENTAL)"
2149 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3
2150 ---help---
2151 Say Y here to include the FAST floating point emulator in the kernel.
2152 This is an experimental much faster emulator which now also has full
2153 precision for the mantissa. It does not support any exceptions.
2154 It is very simple, and approximately 3-6 times faster than NWFPE.
2155
2156 It should be sufficient for most programs. It may be not suitable
2157 for scientific calculations, but you have to check this for yourself.
2158 If you do not feel you need a faster FP emulation you should better
2159 choose NWFPE.
2160
2161config VFP
2162 bool "VFP-format floating point maths"
2163 depends on CPU_V6 || CPU_V6K || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
2164 help
2165 Say Y to include VFP support code in the kernel. This is needed
2166 if your hardware includes a VFP unit.
2167
2168 Please see <file:Documentation/arm/VFP/release-notes.txt> for
2169 release notes and additional status information.
2170
2171 Say N if your target does not have VFP hardware.
2172
2173config VFPv3
2174 bool
2175 depends on VFP
2176 default y if CPU_V7
2177
2178config NEON
2179 bool "Advanced SIMD (NEON) Extension support"
2180 depends on VFPv3 && CPU_V7
2181 help
2182 Say Y to include support code for NEON, the ARMv7 Advanced SIMD
2183 Extension.
2184
2185config KERNEL_MODE_NEON
2186 bool "Support for NEON in kernel mode"
2187 depends on NEON && AEABI
2188 help
2189 Say Y to include support for NEON in kernel mode.
2190
2191endmenu
2192
2193menu "Userspace binary formats"
2194
2195source "fs/Kconfig.binfmt"
2196
2197endmenu
2198
2199menu "Power management options"
2200
2201source "kernel/power/Kconfig"
2202
2203config ARCH_SUSPEND_POSSIBLE
2204 depends on CPU_ARM920T || CPU_ARM926T || CPU_FEROCEON || CPU_SA1100 || \
2205 CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7M || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK
2206 def_bool y
2207
2208config ARM_CPU_SUSPEND
2209 def_bool PM_SLEEP || BL_SWITCHER || ARM_PSCI_FW
2210 depends on ARCH_SUSPEND_POSSIBLE
2211
2212config ARCH_HIBERNATION_POSSIBLE
2213 bool
2214 depends on MMU
2215 default y if ARCH_SUSPEND_POSSIBLE
2216
2217endmenu
2218
2219source "net/Kconfig"
2220
2221source "drivers/Kconfig"
2222
2223source "drivers/firmware/Kconfig"
2224
2225source "fs/Kconfig"
2226
2227source "arch/arm/Kconfig.debug"
2228
2229source "security/Kconfig"
2230
2231source "crypto/Kconfig"
2232if CRYPTO
2233source "arch/arm/crypto/Kconfig"
2234endif
2235
2236source "lib/Kconfig"
2237
2238source "arch/arm/kvm/Kconfig"