4 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
5 select ARCH_HAS_ELF_RANDOMIZE
6 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
7 select ARCH_HAVE_CUSTOM_GPIO_H
8 select ARCH_HAS_GCOV_PROFILE_ALL
9 select ARCH_MIGHT_HAVE_PC_PARPORT
10 select ARCH_SUPPORTS_ATOMIC_RMW
11 select ARCH_USE_BUILTIN_BSWAP
12 select ARCH_USE_CMPXCHG_LOCKREF
13 select ARCH_WANT_IPC_PARSE_VERSION
14 select BUILDTIME_EXTABLE_SORT if MMU
15 select CLONE_BACKWARDS
16 select CPU_PM if (SUSPEND || CPU_IDLE)
17 select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS
19 select EDAC_ATOMIC_SCRUB
20 select GENERIC_ALLOCATOR
21 select GENERIC_ATOMIC64 if (CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI)
22 select GENERIC_CLOCKEVENTS_BROADCAST if SMP
23 select GENERIC_IDLE_POLL_SETUP
24 select GENERIC_IRQ_PROBE
25 select GENERIC_IRQ_SHOW
26 select GENERIC_IRQ_SHOW_LEVEL
27 select GENERIC_PCI_IOMAP
28 select GENERIC_SCHED_CLOCK
29 select GENERIC_SMP_IDLE_THREAD
30 select GENERIC_STRNCPY_FROM_USER
31 select GENERIC_STRNLEN_USER
32 select HANDLE_DOMAIN_IRQ
33 select HARDIRQS_SW_RESEND
34 select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
35 select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
36 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32
37 select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32
38 select HAVE_ARCH_SECCOMP_FILTER if (AEABI && !OABI_COMPAT)
39 select HAVE_ARCH_TRACEHOOK
41 select HAVE_CC_STACKPROTECTOR
42 select HAVE_CONTEXT_TRACKING
43 select HAVE_C_RECORDMCOUNT
44 select HAVE_DEBUG_KMEMLEAK
45 select HAVE_DMA_API_DEBUG
47 select HAVE_DMA_CONTIGUOUS if MMU
48 select HAVE_DYNAMIC_FTRACE if (!XIP_KERNEL) && !CPU_ENDIAN_BE32
49 select HAVE_EFFICIENT_UNALIGNED_ACCESS if (CPU_V6 || CPU_V6K || CPU_V7) && MMU
50 select HAVE_FTRACE_MCOUNT_RECORD if (!XIP_KERNEL)
51 select HAVE_FUNCTION_GRAPH_TRACER if (!THUMB2_KERNEL)
52 select HAVE_FUNCTION_TRACER if (!XIP_KERNEL)
53 select HAVE_GENERIC_DMA_COHERENT
54 select HAVE_HW_BREAKPOINT if (PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7))
55 select HAVE_IDE if PCI || ISA || PCMCIA
56 select HAVE_IRQ_TIME_ACCOUNTING
57 select HAVE_KERNEL_GZIP
58 select HAVE_KERNEL_LZ4
59 select HAVE_KERNEL_LZMA
60 select HAVE_KERNEL_LZO
62 select HAVE_KPROBES if !XIP_KERNEL && !CPU_ENDIAN_BE32 && !CPU_V7M
63 select HAVE_KRETPROBES if (HAVE_KPROBES)
65 select HAVE_MOD_ARCH_SPECIFIC
66 select HAVE_OPROFILE if (HAVE_PERF_EVENTS)
67 select HAVE_OPTPROBES if !THUMB2_KERNEL
68 select HAVE_PERF_EVENTS
70 select HAVE_PERF_USER_STACK_DUMP
71 select HAVE_RCU_TABLE_FREE if (SMP && ARM_LPAE)
72 select HAVE_REGS_AND_STACK_ACCESS_API
73 select HAVE_SYSCALL_TRACEPOINTS
75 select HAVE_VIRT_CPU_ACCOUNTING_GEN
76 select IRQ_FORCED_THREADING
77 select MODULES_USE_ELF_REL
79 select OF_EARLY_FLATTREE if OF
80 select OF_RESERVED_MEM if OF
82 select OLD_SIGSUSPEND3
83 select PERF_USE_VMALLOC
85 select SYS_SUPPORTS_APM_EMULATION
86 # Above selects are sorted alphabetically; please add new ones
87 # according to that. Thanks.
89 The ARM series is a line of low-power-consumption RISC chip designs
90 licensed by ARM Ltd and targeted at embedded applications and
91 handhelds such as the Compaq IPAQ. ARM-based PCs are no longer
92 manufactured, but legacy ARM-based PC hardware remains popular in
93 Europe. There is an ARM Linux project with a web page at
94 <http://www.arm.linux.org.uk/>.
96 config ARM_HAS_SG_CHAIN
97 select ARCH_HAS_SG_CHAIN
100 config NEED_SG_DMA_LENGTH
103 config ARM_DMA_USE_IOMMU
105 select ARM_HAS_SG_CHAIN
106 select NEED_SG_DMA_LENGTH
110 config ARM_DMA_IOMMU_ALIGNMENT
111 int "Maximum PAGE_SIZE order of alignment for DMA IOMMU buffers"
115 DMA mapping framework by default aligns all buffers to the smallest
116 PAGE_SIZE order which is greater than or equal to the requested buffer
117 size. This works well for buffers up to a few hundreds kilobytes, but
118 for larger buffers it just a waste of address space. Drivers which has
119 relatively small addressing window (like 64Mib) might run out of
120 virtual space with just a few allocations.
122 With this parameter you can specify the maximum PAGE_SIZE order for
123 DMA IOMMU buffers. Larger buffers will be aligned only to this
124 specified order. The order is expressed as a power of two multiplied
129 config MIGHT_HAVE_PCI
132 config SYS_SUPPORTS_APM_EMULATION
137 select GENERIC_ALLOCATOR
148 The Extended Industry Standard Architecture (EISA) bus was
149 developed as an open alternative to the IBM MicroChannel bus.
151 The EISA bus provided some of the features of the IBM MicroChannel
152 bus while maintaining backward compatibility with cards made for
153 the older ISA bus. The EISA bus saw limited use between 1988 and
154 1995 when it was made obsolete by the PCI bus.
156 Say Y here if you are building a kernel for an EISA-based machine.
163 config STACKTRACE_SUPPORT
167 config HAVE_LATENCYTOP_SUPPORT
172 config LOCKDEP_SUPPORT
176 config TRACE_IRQFLAGS_SUPPORT
180 config RWSEM_XCHGADD_ALGORITHM
184 config ARCH_HAS_ILOG2_U32
187 config ARCH_HAS_ILOG2_U64
190 config ARCH_HAS_BANDGAP
193 config FIX_EARLYCON_MEM
196 config GENERIC_HWEIGHT
200 config GENERIC_CALIBRATE_DELAY
204 config ARCH_MAY_HAVE_PC_FDC
210 config NEED_DMA_MAP_STATE
213 config ARCH_SUPPORTS_UPROBES
216 config ARCH_HAS_DMA_SET_COHERENT_MASK
219 config GENERIC_ISA_DMA
225 config NEED_RET_TO_USER
233 default 0xffff0000 if MMU || CPU_HIGH_VECTOR
234 default DRAM_BASE if REMAP_VECTORS_TO_RAM
237 The base address of exception vectors. This must be two pages
240 config ARM_PATCH_PHYS_VIRT
241 bool "Patch physical to virtual translations at runtime" if EMBEDDED
243 depends on !XIP_KERNEL && MMU
244 depends on !ARCH_REALVIEW || !SPARSEMEM
246 Patch phys-to-virt and virt-to-phys translation functions at
247 boot and module load time according to the position of the
248 kernel in system memory.
250 This can only be used with non-XIP MMU kernels where the base
251 of physical memory is at a 16MB boundary.
253 Only disable this option if you know that you do not require
254 this feature (eg, building a kernel for a single machine) and
255 you need to shrink the kernel to the minimal size.
257 config NEED_MACH_IO_H
260 Select this when mach/io.h is required to provide special
261 definitions for this platform. The need for mach/io.h should
262 be avoided when possible.
264 config NEED_MACH_MEMORY_H
267 Select this when mach/memory.h is required to provide special
268 definitions for this platform. The need for mach/memory.h should
269 be avoided when possible.
272 hex "Physical address of main memory" if MMU
273 depends on !ARM_PATCH_PHYS_VIRT
274 default DRAM_BASE if !MMU
275 default 0x00000000 if ARCH_EBSA110 || \
280 (ARCH_REALVIEW && !REALVIEW_HIGH_PHYS_OFFSET)
281 default 0x10000000 if ARCH_OMAP1 || ARCH_RPC
282 default 0x20000000 if ARCH_S5PV210
283 default 0x70000000 if REALVIEW_HIGH_PHYS_OFFSET
284 default 0xc0000000 if ARCH_SA1100
286 Please provide the physical address corresponding to the
287 location of main memory in your system.
293 config PGTABLE_LEVELS
295 default 3 if ARM_LPAE
298 source "init/Kconfig"
300 source "kernel/Kconfig.freezer"
305 bool "MMU-based Paged Memory Management Support"
308 Select if you want MMU-based virtualised addressing space
309 support by paged memory management. If unsure, say 'Y'.
312 # The "ARM system type" choice list is ordered alphabetically by option
313 # text. Please add new entries in the option alphabetic order.
316 prompt "ARM system type"
317 default ARCH_VERSATILE if !MMU
318 default ARCH_MULTIPLATFORM if MMU
320 config ARCH_MULTIPLATFORM
321 bool "Allow multiple platforms to be selected"
323 select ARCH_WANT_OPTIONAL_GPIOLIB
324 select ARM_HAS_SG_CHAIN
325 select ARM_PATCH_PHYS_VIRT
329 select GENERIC_CLOCKEVENTS
330 select MIGHT_HAVE_PCI
331 select MULTI_IRQ_HANDLER
335 config ARM_SINGLE_ARMV7M
336 bool "ARMv7-M based platforms (Cortex-M0/M3/M4)"
338 select ARCH_WANT_OPTIONAL_GPIOLIB
344 select GENERIC_CLOCKEVENTS
350 bool "ARM Ltd. RealView family"
351 select ARCH_WANT_OPTIONAL_GPIOLIB
353 select ARM_TIMER_SP804
355 select COMMON_CLK_VERSATILE
356 select GENERIC_CLOCKEVENTS
357 select GPIO_PL061 if GPIOLIB
359 select NEED_MACH_MEMORY_H
360 select PLAT_VERSATILE
361 select PLAT_VERSATILE_SCHED_CLOCK
363 This enables support for ARM Ltd RealView boards.
365 config ARCH_VERSATILE
366 bool "ARM Ltd. Versatile family"
367 select ARCH_WANT_OPTIONAL_GPIOLIB
369 select ARM_TIMER_SP804
372 select GENERIC_CLOCKEVENTS
373 select HAVE_MACH_CLKDEV
375 select PLAT_VERSATILE
376 select PLAT_VERSATILE_CLOCK
377 select PLAT_VERSATILE_SCHED_CLOCK
378 select VERSATILE_FPGA_IRQ
380 This enables support for ARM Ltd Versatile board.
383 bool "Cirrus Logic CLPS711x/EP721x/EP731x-based"
384 select ARCH_REQUIRE_GPIOLIB
389 select GENERIC_CLOCKEVENTS
393 Support for Cirrus Logic 711x/721x/731x based boards.
396 bool "Cortina Systems Gemini"
397 select ARCH_REQUIRE_GPIOLIB
400 select GENERIC_CLOCKEVENTS
402 Support for the Cortina Systems Gemini family SoCs
406 select ARCH_USES_GETTIMEOFFSET
409 select NEED_MACH_IO_H
410 select NEED_MACH_MEMORY_H
413 This is an evaluation board for the StrongARM processor available
414 from Digital. It has limited hardware on-board, including an
415 Ethernet interface, two PCMCIA sockets, two serial ports and a
420 select ARCH_HAS_HOLES_MEMORYMODEL
421 select ARCH_REQUIRE_GPIOLIB
423 select ARM_PATCH_PHYS_VIRT
429 select GENERIC_CLOCKEVENTS
431 This enables support for the Cirrus EP93xx series of CPUs.
433 config ARCH_FOOTBRIDGE
437 select GENERIC_CLOCKEVENTS
439 select NEED_MACH_IO_H if !MMU
440 select NEED_MACH_MEMORY_H
442 Support for systems based on the DC21285 companion chip
443 ("FootBridge"), such as the Simtec CATS and the Rebel NetWinder.
446 bool "Hilscher NetX based"
450 select GENERIC_CLOCKEVENTS
452 This enables support for systems based on the Hilscher NetX Soc
458 select NEED_MACH_MEMORY_H
459 select NEED_RET_TO_USER
465 Support for Intel's IOP13XX (XScale) family of processors.
470 select ARCH_REQUIRE_GPIOLIB
473 select NEED_RET_TO_USER
477 Support for Intel's 80219 and IOP32X (XScale) family of
483 select ARCH_REQUIRE_GPIOLIB
486 select NEED_RET_TO_USER
490 Support for Intel's IOP33X (XScale) family of processors.
495 select ARCH_HAS_DMA_SET_COHERENT_MASK
496 select ARCH_REQUIRE_GPIOLIB
497 select ARCH_SUPPORTS_BIG_ENDIAN
500 select DMABOUNCE if PCI
501 select GENERIC_CLOCKEVENTS
502 select MIGHT_HAVE_PCI
503 select NEED_MACH_IO_H
504 select USB_EHCI_BIG_ENDIAN_DESC
505 select USB_EHCI_BIG_ENDIAN_MMIO
507 Support for Intel's IXP4XX (XScale) family of processors.
511 select ARCH_REQUIRE_GPIOLIB
513 select GENERIC_CLOCKEVENTS
514 select MIGHT_HAVE_PCI
518 select PLAT_ORION_LEGACY
520 Support for the Marvell Dove SoC 88AP510
523 bool "Marvell MV78xx0"
524 select ARCH_REQUIRE_GPIOLIB
526 select GENERIC_CLOCKEVENTS
529 select PLAT_ORION_LEGACY
531 Support for the following Marvell MV78xx0 series SoCs:
537 select ARCH_REQUIRE_GPIOLIB
539 select GENERIC_CLOCKEVENTS
542 select PLAT_ORION_LEGACY
543 select MULTI_IRQ_HANDLER
545 Support for the following Marvell Orion 5x series SoCs:
546 Orion-1 (5181), Orion-VoIP (5181L), Orion-NAS (5182),
547 Orion-2 (5281), Orion-1-90 (6183).
550 bool "Marvell PXA168/910/MMP2"
552 select ARCH_REQUIRE_GPIOLIB
554 select GENERIC_ALLOCATOR
555 select GENERIC_CLOCKEVENTS
558 select MULTI_IRQ_HANDLER
563 Support for Marvell's PXA168/PXA910(MMP) and MMP2 processor line.
566 bool "Micrel/Kendin KS8695"
567 select ARCH_REQUIRE_GPIOLIB
570 select GENERIC_CLOCKEVENTS
571 select NEED_MACH_MEMORY_H
573 Support for Micrel/Kendin KS8695 "Centaur" (ARM922T) based
574 System-on-Chip devices.
577 bool "Nuvoton W90X900 CPU"
578 select ARCH_REQUIRE_GPIOLIB
582 select GENERIC_CLOCKEVENTS
584 Support for Nuvoton (Winbond logic dept.) ARM9 processor,
585 At present, the w90x900 has been renamed nuc900, regarding
586 the ARM series product line, you can login the following
587 link address to know more.
589 <http://www.nuvoton.com/hq/enu/ProductAndSales/ProductLines/
590 ConsumerElectronicsIC/ARMMicrocontroller/ARMMicrocontroller>
594 select ARCH_REQUIRE_GPIOLIB
599 select GENERIC_CLOCKEVENTS
603 Support for the NXP LPC32XX family of processors
606 bool "PXA2xx/PXA3xx-based"
609 select ARCH_REQUIRE_GPIOLIB
610 select ARM_CPU_SUSPEND if PM
616 select GENERIC_CLOCKEVENTS
620 select MULTI_IRQ_HANDLER
624 Support for Intel/Marvell's PXA2xx/PXA3xx processor line.
630 select ARCH_MAY_HAVE_PC_FDC
631 select ARCH_SPARSEMEM_ENABLE
632 select ARCH_USES_GETTIMEOFFSET
636 select HAVE_PATA_PLATFORM
638 select NEED_MACH_IO_H
639 select NEED_MACH_MEMORY_H
643 On the Acorn Risc-PC, Linux can support the internal IDE disk and
644 CD-ROM interface, serial and parallel port, and the floppy drive.
649 select ARCH_REQUIRE_GPIOLIB
650 select ARCH_SPARSEMEM_ENABLE
655 select GENERIC_CLOCKEVENTS
659 select MULTI_IRQ_HANDLER
660 select NEED_MACH_MEMORY_H
663 Support for StrongARM 11x0 based boards.
666 bool "Samsung S3C24XX SoCs"
667 select ARCH_REQUIRE_GPIOLIB
670 select CLKSRC_SAMSUNG_PWM
671 select GENERIC_CLOCKEVENTS
673 select HAVE_S3C2410_I2C if I2C
674 select HAVE_S3C2410_WATCHDOG if WATCHDOG
675 select HAVE_S3C_RTC if RTC_CLASS
676 select MULTI_IRQ_HANDLER
677 select NEED_MACH_IO_H
680 Samsung S3C2410, S3C2412, S3C2413, S3C2416, S3C2440, S3C2442, S3C2443
681 and S3C2450 SoCs based systems, such as the Simtec Electronics BAST
682 (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or the
683 Samsung SMDK2410 development board (and derivatives).
686 bool "Samsung S3C64XX"
687 select ARCH_REQUIRE_GPIOLIB
692 select CLKSRC_SAMSUNG_PWM
693 select COMMON_CLK_SAMSUNG
695 select GENERIC_CLOCKEVENTS
697 select HAVE_S3C2410_I2C if I2C
698 select HAVE_S3C2410_WATCHDOG if WATCHDOG
702 select PM_GENERIC_DOMAINS if PM
704 select S3C_GPIO_TRACK
706 select SAMSUNG_WAKEMASK
707 select SAMSUNG_WDT_RESET
709 Samsung S3C64XX series based systems
713 select ARCH_HAS_HOLES_MEMORYMODEL
714 select ARCH_REQUIRE_GPIOLIB
716 select GENERIC_ALLOCATOR
717 select GENERIC_CLOCKEVENTS
718 select GENERIC_IRQ_CHIP
723 Support for TI's DaVinci platform.
728 select ARCH_HAS_HOLES_MEMORYMODEL
730 select ARCH_REQUIRE_GPIOLIB
733 select GENERIC_CLOCKEVENTS
734 select GENERIC_IRQ_CHIP
737 select MULTI_IRQ_HANDLER
738 select NEED_MACH_IO_H if PCCARD
739 select NEED_MACH_MEMORY_H
742 Support for older TI OMAP1 (omap7xx, omap15xx or omap16xx)
746 menu "Multiple platform selection"
747 depends on ARCH_MULTIPLATFORM
749 comment "CPU Core family selection"
752 bool "ARMv4 based platforms (FA526)"
753 depends on !ARCH_MULTI_V6_V7
754 select ARCH_MULTI_V4_V5
757 config ARCH_MULTI_V4T
758 bool "ARMv4T based platforms (ARM720T, ARM920T, ...)"
759 depends on !ARCH_MULTI_V6_V7
760 select ARCH_MULTI_V4_V5
761 select CPU_ARM920T if !(CPU_ARM7TDMI || CPU_ARM720T || \
762 CPU_ARM740T || CPU_ARM9TDMI || CPU_ARM922T || \
763 CPU_ARM925T || CPU_ARM940T)
766 bool "ARMv5 based platforms (ARM926T, XSCALE, PJ1, ...)"
767 depends on !ARCH_MULTI_V6_V7
768 select ARCH_MULTI_V4_V5
769 select CPU_ARM926T if !(CPU_ARM946E || CPU_ARM1020 || \
770 CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || \
771 CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_FEROCEON)
773 config ARCH_MULTI_V4_V5
777 bool "ARMv6 based platforms (ARM11)"
778 select ARCH_MULTI_V6_V7
782 bool "ARMv7 based platforms (Cortex-A, PJ4, Scorpion, Krait)"
784 select ARCH_MULTI_V6_V7
788 config ARCH_MULTI_V6_V7
790 select MIGHT_HAVE_CACHE_L2X0
792 config ARCH_MULTI_CPU_AUTO
793 def_bool !(ARCH_MULTI_V4 || ARCH_MULTI_V4T || ARCH_MULTI_V6_V7)
799 bool "Dummy Virtual Machine" if ARCH_MULTI_V7
804 select HAVE_ARM_ARCH_TIMER
807 # This is sorted alphabetically by mach-* pathname. However, plat-*
808 # Kconfigs may be included either alphabetically (according to the
809 # plat- suffix) or along side the corresponding mach-* source.
811 source "arch/arm/mach-mvebu/Kconfig"
813 source "arch/arm/mach-alpine/Kconfig"
815 source "arch/arm/mach-asm9260/Kconfig"
817 source "arch/arm/mach-at91/Kconfig"
819 source "arch/arm/mach-axxia/Kconfig"
821 source "arch/arm/mach-bcm/Kconfig"
823 source "arch/arm/mach-berlin/Kconfig"
825 source "arch/arm/mach-clps711x/Kconfig"
827 source "arch/arm/mach-cns3xxx/Kconfig"
829 source "arch/arm/mach-davinci/Kconfig"
831 source "arch/arm/mach-digicolor/Kconfig"
833 source "arch/arm/mach-dove/Kconfig"
835 source "arch/arm/mach-ep93xx/Kconfig"
837 source "arch/arm/mach-footbridge/Kconfig"
839 source "arch/arm/mach-gemini/Kconfig"
841 source "arch/arm/mach-highbank/Kconfig"
843 source "arch/arm/mach-hisi/Kconfig"
845 source "arch/arm/mach-integrator/Kconfig"
847 source "arch/arm/mach-iop32x/Kconfig"
849 source "arch/arm/mach-iop33x/Kconfig"
851 source "arch/arm/mach-iop13xx/Kconfig"
853 source "arch/arm/mach-ixp4xx/Kconfig"
855 source "arch/arm/mach-keystone/Kconfig"
857 source "arch/arm/mach-ks8695/Kconfig"
859 source "arch/arm/mach-meson/Kconfig"
861 source "arch/arm/mach-moxart/Kconfig"
863 source "arch/arm/mach-mv78xx0/Kconfig"
865 source "arch/arm/mach-imx/Kconfig"
867 source "arch/arm/mach-mediatek/Kconfig"
869 source "arch/arm/mach-mxs/Kconfig"
871 source "arch/arm/mach-netx/Kconfig"
873 source "arch/arm/mach-nomadik/Kconfig"
875 source "arch/arm/mach-nspire/Kconfig"
877 source "arch/arm/plat-omap/Kconfig"
879 source "arch/arm/mach-omap1/Kconfig"
881 source "arch/arm/mach-omap2/Kconfig"
883 source "arch/arm/mach-orion5x/Kconfig"
885 source "arch/arm/mach-picoxcell/Kconfig"
887 source "arch/arm/mach-pxa/Kconfig"
888 source "arch/arm/plat-pxa/Kconfig"
890 source "arch/arm/mach-mmp/Kconfig"
892 source "arch/arm/mach-qcom/Kconfig"
894 source "arch/arm/mach-realview/Kconfig"
896 source "arch/arm/mach-rockchip/Kconfig"
898 source "arch/arm/mach-sa1100/Kconfig"
900 source "arch/arm/mach-socfpga/Kconfig"
902 source "arch/arm/mach-spear/Kconfig"
904 source "arch/arm/mach-sti/Kconfig"
906 source "arch/arm/mach-s3c24xx/Kconfig"
908 source "arch/arm/mach-s3c64xx/Kconfig"
910 source "arch/arm/mach-s5pv210/Kconfig"
912 source "arch/arm/mach-exynos/Kconfig"
913 source "arch/arm/plat-samsung/Kconfig"
915 source "arch/arm/mach-shmobile/Kconfig"
917 source "arch/arm/mach-sunxi/Kconfig"
919 source "arch/arm/mach-prima2/Kconfig"
921 source "arch/arm/mach-tegra/Kconfig"
923 source "arch/arm/mach-u300/Kconfig"
925 source "arch/arm/mach-uniphier/Kconfig"
927 source "arch/arm/mach-ux500/Kconfig"
929 source "arch/arm/mach-versatile/Kconfig"
931 source "arch/arm/mach-vexpress/Kconfig"
932 source "arch/arm/plat-versatile/Kconfig"
934 source "arch/arm/mach-vt8500/Kconfig"
936 source "arch/arm/mach-w90x900/Kconfig"
938 source "arch/arm/mach-zx/Kconfig"
940 source "arch/arm/mach-zynq/Kconfig"
942 # ARMv7-M architecture
944 bool "Energy Micro efm32"
945 depends on ARM_SINGLE_ARMV7M
946 select ARCH_REQUIRE_GPIOLIB
948 Support for Energy Micro's (now Silicon Labs) efm32 Giant Gecko
952 bool "NXP LPC18xx/LPC43xx"
953 depends on ARM_SINGLE_ARMV7M
954 select ARCH_HAS_RESET_CONTROLLER
956 select CLKSRC_LPC32XX
959 Support for NXP's LPC18xx Cortex-M3 and LPC43xx Cortex-M4
960 high performance microcontrollers.
963 bool "STMicrolectronics STM32"
964 depends on ARM_SINGLE_ARMV7M
965 select ARCH_HAS_RESET_CONTROLLER
966 select ARMV7M_SYSTICK
968 select RESET_CONTROLLER
970 Support for STMicroelectronics STM32 processors.
972 # Definitions to make life easier
978 select GENERIC_CLOCKEVENTS
984 select GENERIC_IRQ_CHIP
987 config PLAT_ORION_LEGACY
994 config PLAT_VERSATILE
997 source "arch/arm/firmware/Kconfig"
999 source arch/arm/mm/Kconfig
1002 bool "Enable iWMMXt support"
1003 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B
1004 default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 || CPU_PJ4B
1006 Enable support for iWMMXt context switching at run time if
1007 running on a CPU that supports it.
1009 config MULTI_IRQ_HANDLER
1012 Allow each machine to specify it's own IRQ handler at run time.
1015 source "arch/arm/Kconfig-nommu"
1018 config PJ4B_ERRATA_4742
1019 bool "PJ4B Errata 4742: IDLE Wake Up Commands can Cause the CPU Core to Cease Operation"
1020 depends on CPU_PJ4B && MACH_ARMADA_370
1023 When coming out of either a Wait for Interrupt (WFI) or a Wait for
1024 Event (WFE) IDLE states, a specific timing sensitivity exists between
1025 the retiring WFI/WFE instructions and the newly issued subsequent
1026 instructions. This sensitivity can result in a CPU hang scenario.
1028 The software must insert either a Data Synchronization Barrier (DSB)
1029 or Data Memory Barrier (DMB) command immediately after the WFI/WFE
1032 config ARM_ERRATA_326103
1033 bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory"
1036 Executing a SWP instruction to read-only memory does not set bit 11
1037 of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to
1038 treat the access as a read, preventing a COW from occurring and
1039 causing the faulting task to livelock.
1041 config ARM_ERRATA_411920
1042 bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
1043 depends on CPU_V6 || CPU_V6K
1045 Invalidation of the Instruction Cache operation can
1046 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
1047 It does not affect the MPCore. This option enables the ARM Ltd.
1048 recommended workaround.
1050 config ARM_ERRATA_430973
1051 bool "ARM errata: Stale prediction on replaced interworking branch"
1054 This option enables the workaround for the 430973 Cortex-A8
1055 r1p* erratum. If a code sequence containing an ARM/Thumb
1056 interworking branch is replaced with another code sequence at the
1057 same virtual address, whether due to self-modifying code or virtual
1058 to physical address re-mapping, Cortex-A8 does not recover from the
1059 stale interworking branch prediction. This results in Cortex-A8
1060 executing the new code sequence in the incorrect ARM or Thumb state.
1061 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
1062 and also flushes the branch target cache at every context switch.
1063 Note that setting specific bits in the ACTLR register may not be
1064 available in non-secure mode.
1066 config ARM_ERRATA_458693
1067 bool "ARM errata: Processor deadlock when a false hazard is created"
1069 depends on !ARCH_MULTIPLATFORM
1071 This option enables the workaround for the 458693 Cortex-A8 (r2p0)
1072 erratum. For very specific sequences of memory operations, it is
1073 possible for a hazard condition intended for a cache line to instead
1074 be incorrectly associated with a different cache line. This false
1075 hazard might then cause a processor deadlock. The workaround enables
1076 the L1 caching of the NEON accesses and disables the PLD instruction
1077 in the ACTLR register. Note that setting specific bits in the ACTLR
1078 register may not be available in non-secure mode.
1080 config ARM_ERRATA_460075
1081 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
1083 depends on !ARCH_MULTIPLATFORM
1085 This option enables the workaround for the 460075 Cortex-A8 (r2p0)
1086 erratum. Any asynchronous access to the L2 cache may encounter a
1087 situation in which recent store transactions to the L2 cache are lost
1088 and overwritten with stale memory contents from external memory. The
1089 workaround disables the write-allocate mode for the L2 cache via the
1090 ACTLR register. Note that setting specific bits in the ACTLR register
1091 may not be available in non-secure mode.
1093 config ARM_ERRATA_742230
1094 bool "ARM errata: DMB operation may be faulty"
1095 depends on CPU_V7 && SMP
1096 depends on !ARCH_MULTIPLATFORM
1098 This option enables the workaround for the 742230 Cortex-A9
1099 (r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction
1100 between two write operations may not ensure the correct visibility
1101 ordering of the two writes. This workaround sets a specific bit in
1102 the diagnostic register of the Cortex-A9 which causes the DMB
1103 instruction to behave as a DSB, ensuring the correct behaviour of
1106 config ARM_ERRATA_742231
1107 bool "ARM errata: Incorrect hazard handling in the SCU may lead to data corruption"
1108 depends on CPU_V7 && SMP
1109 depends on !ARCH_MULTIPLATFORM
1111 This option enables the workaround for the 742231 Cortex-A9
1112 (r2p0..r2p2) erratum. Under certain conditions, specific to the
1113 Cortex-A9 MPCore micro-architecture, two CPUs working in SMP mode,
1114 accessing some data located in the same cache line, may get corrupted
1115 data due to bad handling of the address hazard when the line gets
1116 replaced from one of the CPUs at the same time as another CPU is
1117 accessing it. This workaround sets specific bits in the diagnostic
1118 register of the Cortex-A9 which reduces the linefill issuing
1119 capabilities of the processor.
1121 config ARM_ERRATA_643719
1122 bool "ARM errata: LoUIS bit field in CLIDR register is incorrect"
1123 depends on CPU_V7 && SMP
1126 This option enables the workaround for the 643719 Cortex-A9 (prior to
1127 r1p0) erratum. On affected cores the LoUIS bit field of the CLIDR
1128 register returns zero when it should return one. The workaround
1129 corrects this value, ensuring cache maintenance operations which use
1130 it behave as intended and avoiding data corruption.
1132 config ARM_ERRATA_720789
1133 bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID"
1136 This option enables the workaround for the 720789 Cortex-A9 (prior to
1137 r2p0) erratum. A faulty ASID can be sent to the other CPUs for the
1138 broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS.
1139 As a consequence of this erratum, some TLB entries which should be
1140 invalidated are not, resulting in an incoherency in the system page
1141 tables. The workaround changes the TLB flushing routines to invalidate
1142 entries regardless of the ASID.
1144 config ARM_ERRATA_743622
1145 bool "ARM errata: Faulty hazard checking in the Store Buffer may lead to data corruption"
1147 depends on !ARCH_MULTIPLATFORM
1149 This option enables the workaround for the 743622 Cortex-A9
1150 (r2p*) erratum. Under very rare conditions, a faulty
1151 optimisation in the Cortex-A9 Store Buffer may lead to data
1152 corruption. This workaround sets a specific bit in the diagnostic
1153 register of the Cortex-A9 which disables the Store Buffer
1154 optimisation, preventing the defect from occurring. This has no
1155 visible impact on the overall performance or power consumption of the
1158 config ARM_ERRATA_751472
1159 bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation"
1161 depends on !ARCH_MULTIPLATFORM
1163 This option enables the workaround for the 751472 Cortex-A9 (prior
1164 to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the
1165 completion of a following broadcasted operation if the second
1166 operation is received by a CPU before the ICIALLUIS has completed,
1167 potentially leading to corrupted entries in the cache or TLB.
1169 config ARM_ERRATA_754322
1170 bool "ARM errata: possible faulty MMU translations following an ASID switch"
1173 This option enables the workaround for the 754322 Cortex-A9 (r2p*,
1174 r3p*) erratum. A speculative memory access may cause a page table walk
1175 which starts prior to an ASID switch but completes afterwards. This
1176 can populate the micro-TLB with a stale entry which may be hit with
1177 the new ASID. This workaround places two dsb instructions in the mm
1178 switching code so that no page table walks can cross the ASID switch.
1180 config ARM_ERRATA_754327
1181 bool "ARM errata: no automatic Store Buffer drain"
1182 depends on CPU_V7 && SMP
1184 This option enables the workaround for the 754327 Cortex-A9 (prior to
1185 r2p0) erratum. The Store Buffer does not have any automatic draining
1186 mechanism and therefore a livelock may occur if an external agent
1187 continuously polls a memory location waiting to observe an update.
1188 This workaround defines cpu_relax() as smp_mb(), preventing correctly
1189 written polling loops from denying visibility of updates to memory.
1191 config ARM_ERRATA_364296
1192 bool "ARM errata: Possible cache data corruption with hit-under-miss enabled"
1195 This options enables the workaround for the 364296 ARM1136
1196 r0p2 erratum (possible cache data corruption with
1197 hit-under-miss enabled). It sets the undocumented bit 31 in
1198 the auxiliary control register and the FI bit in the control
1199 register, thus disabling hit-under-miss without putting the
1200 processor into full low interrupt latency mode. ARM11MPCore
1203 config ARM_ERRATA_764369
1204 bool "ARM errata: Data cache line maintenance operation by MVA may not succeed"
1205 depends on CPU_V7 && SMP
1207 This option enables the workaround for erratum 764369
1208 affecting Cortex-A9 MPCore with two or more processors (all
1209 current revisions). Under certain timing circumstances, a data
1210 cache line maintenance operation by MVA targeting an Inner
1211 Shareable memory region may fail to proceed up to either the
1212 Point of Coherency or to the Point of Unification of the
1213 system. This workaround adds a DSB instruction before the
1214 relevant cache maintenance functions and sets a specific bit
1215 in the diagnostic control register of the SCU.
1217 config ARM_ERRATA_775420
1218 bool "ARM errata: A data cache maintenance operation which aborts, might lead to deadlock"
1221 This option enables the workaround for the 775420 Cortex-A9 (r2p2,
1222 r2p6,r2p8,r2p10,r3p0) erratum. In case a date cache maintenance
1223 operation aborts with MMU exception, it might cause the processor
1224 to deadlock. This workaround puts DSB before executing ISB if
1225 an abort may occur on cache maintenance.
1227 config ARM_ERRATA_798181
1228 bool "ARM errata: TLBI/DSB failure on Cortex-A15"
1229 depends on CPU_V7 && SMP
1231 On Cortex-A15 (r0p0..r3p2) the TLBI*IS/DSB operations are not
1232 adequately shooting down all use of the old entries. This
1233 option enables the Linux kernel workaround for this erratum
1234 which sends an IPI to the CPUs that are running the same ASID
1235 as the one being invalidated.
1237 config ARM_ERRATA_773022
1238 bool "ARM errata: incorrect instructions may be executed from loop buffer"
1241 This option enables the workaround for the 773022 Cortex-A15
1242 (up to r0p4) erratum. In certain rare sequences of code, the
1243 loop buffer may deliver incorrect instructions. This
1244 workaround disables the loop buffer to avoid the erratum.
1248 source "arch/arm/common/Kconfig"
1255 Find out whether you have ISA slots on your motherboard. ISA is the
1256 name of a bus system, i.e. the way the CPU talks to the other stuff
1257 inside your box. Other bus systems are PCI, EISA, MicroChannel
1258 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1259 newer boards don't support it. If you have ISA, say Y, otherwise N.
1261 # Select ISA DMA controller support
1266 # Select ISA DMA interface
1271 bool "PCI support" if MIGHT_HAVE_PCI
1273 Find out whether you have a PCI motherboard. PCI is the name of a
1274 bus system, i.e. the way the CPU talks to the other stuff inside
1275 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1276 VESA. If you have PCI, say Y, otherwise N.
1282 config PCI_DOMAINS_GENERIC
1283 def_bool PCI_DOMAINS
1285 config PCI_NANOENGINE
1286 bool "BSE nanoEngine PCI support"
1287 depends on SA1100_NANOENGINE
1289 Enable PCI on the BSE nanoEngine board.
1294 config PCI_HOST_ITE8152
1296 depends on PCI && MACH_ARMCORE
1300 source "drivers/pci/Kconfig"
1301 source "drivers/pci/pcie/Kconfig"
1303 source "drivers/pcmcia/Kconfig"
1307 menu "Kernel Features"
1312 This option should be selected by machines which have an SMP-
1315 The only effect of this option is to make the SMP-related
1316 options available to the user for configuration.
1319 bool "Symmetric Multi-Processing"
1320 depends on CPU_V6K || CPU_V7
1321 depends on GENERIC_CLOCKEVENTS
1323 depends on MMU || ARM_MPU
1326 This enables support for systems with more than one CPU. If you have
1327 a system with only one CPU, say N. If you have a system with more
1328 than one CPU, say Y.
1330 If you say N here, the kernel will run on uni- and multiprocessor
1331 machines, but will use only one CPU of a multiprocessor machine. If
1332 you say Y here, the kernel will run on many, but not all,
1333 uniprocessor machines. On a uniprocessor machine, the kernel
1334 will run faster if you say N here.
1336 See also <file:Documentation/x86/i386/IO-APIC.txt>,
1337 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
1338 <http://tldp.org/HOWTO/SMP-HOWTO.html>.
1340 If you don't know what to do here, say N.
1343 bool "Allow booting SMP kernel on uniprocessor systems"
1344 depends on SMP && !XIP_KERNEL && MMU
1347 SMP kernels contain instructions which fail on non-SMP processors.
1348 Enabling this option allows the kernel to modify itself to make
1349 these instructions safe. Disabling it allows about 1K of space
1352 If you don't know what to do here, say Y.
1354 config ARM_CPU_TOPOLOGY
1355 bool "Support cpu topology definition"
1356 depends on SMP && CPU_V7
1359 Support ARM cpu topology definition. The MPIDR register defines
1360 affinity between processors which is then used to describe the cpu
1361 topology of an ARM System.
1364 bool "Multi-core scheduler support"
1365 depends on ARM_CPU_TOPOLOGY
1367 Multi-core scheduler support improves the CPU scheduler's decision
1368 making when dealing with multi-core CPU chips at a cost of slightly
1369 increased overhead in some places. If unsure say N here.
1372 bool "SMT scheduler support"
1373 depends on ARM_CPU_TOPOLOGY
1375 Improves the CPU scheduler's decision making when dealing with
1376 MultiThreading at a cost of slightly increased overhead in some
1377 places. If unsure say N here.
1382 This option enables support for the ARM system coherency unit
1384 config HAVE_ARM_ARCH_TIMER
1385 bool "Architected timer support"
1387 select ARM_ARCH_TIMER
1388 select GENERIC_CLOCKEVENTS
1390 This option enables support for the ARM architected timer
1394 select CLKSRC_OF if OF
1396 This options enables support for the ARM timer and watchdog unit
1399 bool "Multi-Cluster Power Management"
1400 depends on CPU_V7 && SMP
1402 This option provides the common power management infrastructure
1403 for (multi-)cluster based systems, such as big.LITTLE based
1406 config MCPM_QUAD_CLUSTER
1410 To avoid wasting resources unnecessarily, MCPM only supports up
1411 to 2 clusters by default.
1412 Platforms with 3 or 4 clusters that use MCPM must select this
1413 option to allow the additional clusters to be managed.
1416 bool "big.LITTLE support (Experimental)"
1417 depends on CPU_V7 && SMP
1420 This option enables support selections for the big.LITTLE
1421 system architecture.
1424 bool "big.LITTLE switcher support"
1425 depends on BIG_LITTLE && MCPM && HOTPLUG_CPU
1426 select ARM_CPU_SUSPEND
1429 The big.LITTLE "switcher" provides the core functionality to
1430 transparently handle transition between a cluster of A15's
1431 and a cluster of A7's in a big.LITTLE system.
1433 config BL_SWITCHER_DUMMY_IF
1434 tristate "Simple big.LITTLE switcher user interface"
1435 depends on BL_SWITCHER && DEBUG_KERNEL
1437 This is a simple and dummy char dev interface to control
1438 the big.LITTLE switcher core code. It is meant for
1439 debugging purposes only.
1442 prompt "Memory split"
1446 Select the desired split between kernel and user memory.
1448 If you are not absolutely sure what you are doing, leave this
1452 bool "3G/1G user/kernel split"
1453 config VMSPLIT_3G_OPT
1454 bool "3G/1G user/kernel split (for full 1G low memory)"
1456 bool "2G/2G user/kernel split"
1458 bool "1G/3G user/kernel split"
1463 default PHYS_OFFSET if !MMU
1464 default 0x40000000 if VMSPLIT_1G
1465 default 0x80000000 if VMSPLIT_2G
1466 default 0xB0000000 if VMSPLIT_3G_OPT
1470 int "Maximum number of CPUs (2-32)"
1476 bool "Support for hot-pluggable CPUs"
1479 Say Y here to experiment with turning CPUs off and on. CPUs
1480 can be controlled through /sys/devices/system/cpu.
1483 bool "Support for the ARM Power State Coordination Interface (PSCI)"
1487 Say Y here if you want Linux to communicate with system firmware
1488 implementing the PSCI specification for CPU-centric power
1489 management operations described in ARM document number ARM DEN
1490 0022A ("Power State Coordination Interface System Software on
1493 # The GPIO number here must be sorted by descending number. In case of
1494 # a multiplatform kernel, we just want the highest value required by the
1495 # selected platforms.
1498 default 1024 if ARCH_BRCMSTB || ARCH_SHMOBILE || ARCH_TEGRA || \
1500 default 512 if ARCH_EXYNOS || ARCH_KEYSTONE || SOC_OMAP5 || \
1501 SOC_DRA7XX || ARCH_S3C24XX || ARCH_S3C64XX || ARCH_S5PV210
1502 default 416 if ARCH_SUNXI
1503 default 392 if ARCH_U8500
1504 default 352 if ARCH_VT8500
1505 default 288 if ARCH_ROCKCHIP
1506 default 264 if MACH_H4700
1509 Maximum number of GPIOs in the system.
1511 If unsure, leave the default value.
1513 source kernel/Kconfig.preempt
1517 default 200 if ARCH_EBSA110 || ARCH_S3C24XX || \
1518 ARCH_S5PV210 || ARCH_EXYNOS4
1519 default 128 if SOC_AT91RM9200
1523 depends on HZ_FIXED = 0
1524 prompt "Timer frequency"
1548 default HZ_FIXED if HZ_FIXED != 0
1549 default 100 if HZ_100
1550 default 200 if HZ_200
1551 default 250 if HZ_250
1552 default 300 if HZ_300
1553 default 500 if HZ_500
1557 def_bool HIGH_RES_TIMERS
1559 config THUMB2_KERNEL
1560 bool "Compile the kernel in Thumb-2 mode" if !CPU_THUMBONLY
1561 depends on (CPU_V7 || CPU_V7M) && !CPU_V6 && !CPU_V6K
1562 default y if CPU_THUMBONLY
1564 select ARM_ASM_UNIFIED
1567 By enabling this option, the kernel will be compiled in
1568 Thumb-2 mode. A compiler/assembler that understand the unified
1569 ARM-Thumb syntax is needed.
1573 config THUMB2_AVOID_R_ARM_THM_JUMP11
1574 bool "Work around buggy Thumb-2 short branch relocations in gas"
1575 depends on THUMB2_KERNEL && MODULES
1578 Various binutils versions can resolve Thumb-2 branches to
1579 locally-defined, preemptible global symbols as short-range "b.n"
1580 branch instructions.
1582 This is a problem, because there's no guarantee the final
1583 destination of the symbol, or any candidate locations for a
1584 trampoline, are within range of the branch. For this reason, the
1585 kernel does not support fixing up the R_ARM_THM_JUMP11 (102)
1586 relocation in modules at all, and it makes little sense to add
1589 The symptom is that the kernel fails with an "unsupported
1590 relocation" error when loading some modules.
1592 Until fixed tools are available, passing
1593 -fno-optimize-sibling-calls to gcc should prevent gcc generating
1594 code which hits this problem, at the cost of a bit of extra runtime
1595 stack usage in some cases.
1597 The problem is described in more detail at:
1598 https://bugs.launchpad.net/binutils-linaro/+bug/725126
1600 Only Thumb-2 kernels are affected.
1602 Unless you are sure your tools don't have this problem, say Y.
1604 config ARM_ASM_UNIFIED
1608 bool "Use the ARM EABI to compile the kernel"
1610 This option allows for the kernel to be compiled using the latest
1611 ARM ABI (aka EABI). This is only useful if you are using a user
1612 space environment that is also compiled with EABI.
1614 Since there are major incompatibilities between the legacy ABI and
1615 EABI, especially with regard to structure member alignment, this
1616 option also changes the kernel syscall calling convention to
1617 disambiguate both ABIs and allow for backward compatibility support
1618 (selected with CONFIG_OABI_COMPAT).
1620 To use this you need GCC version 4.0.0 or later.
1623 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1624 depends on AEABI && !THUMB2_KERNEL
1626 This option preserves the old syscall interface along with the
1627 new (ARM EABI) one. It also provides a compatibility layer to
1628 intercept syscalls that have structure arguments which layout
1629 in memory differs between the legacy ABI and the new ARM EABI
1630 (only for non "thumb" binaries). This option adds a tiny
1631 overhead to all syscalls and produces a slightly larger kernel.
1633 The seccomp filter system will not be available when this is
1634 selected, since there is no way yet to sensibly distinguish
1635 between calling conventions during filtering.
1637 If you know you'll be using only pure EABI user space then you
1638 can say N here. If this option is not selected and you attempt
1639 to execute a legacy ABI binary then the result will be
1640 UNPREDICTABLE (in fact it can be predicted that it won't work
1641 at all). If in doubt say N.
1643 config ARCH_HAS_HOLES_MEMORYMODEL
1646 config ARCH_SPARSEMEM_ENABLE
1649 config ARCH_SPARSEMEM_DEFAULT
1650 def_bool ARCH_SPARSEMEM_ENABLE
1652 config ARCH_SELECT_MEMORY_MODEL
1653 def_bool ARCH_SPARSEMEM_ENABLE
1655 config HAVE_ARCH_PFN_VALID
1656 def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM
1658 config HAVE_GENERIC_RCU_GUP
1663 bool "High Memory Support"
1666 The address space of ARM processors is only 4 Gigabytes large
1667 and it has to accommodate user address space, kernel address
1668 space as well as some memory mapped IO. That means that, if you
1669 have a large amount of physical memory and/or IO, not all of the
1670 memory can be "permanently mapped" by the kernel. The physical
1671 memory that is not permanently mapped is called "high memory".
1673 Depending on the selected kernel/user memory split, minimum
1674 vmalloc space and actual amount of RAM, you may not need this
1675 option which should result in a slightly faster kernel.
1680 bool "Allocate 2nd-level pagetables from highmem" if EXPERT
1684 The VM uses one page of physical memory for each page table.
1685 For systems with a lot of processes, this can use a lot of
1686 precious low memory, eventually leading to low memory being
1687 consumed by page tables. Setting this option will allow
1688 user-space 2nd level page tables to reside in high memory.
1690 config CPU_SW_DOMAIN_PAN
1691 bool "Enable use of CPU domains to implement privileged no-access"
1692 depends on MMU && !ARM_LPAE
1695 Increase kernel security by ensuring that normal kernel accesses
1696 are unable to access userspace addresses. This can help prevent
1697 use-after-free bugs becoming an exploitable privilege escalation
1698 by ensuring that magic values (such as LIST_POISON) will always
1699 fault when dereferenced.
1701 CPUs with low-vector mappings use a best-efforts implementation.
1702 Their lower 1MB needs to remain accessible for the vectors, but
1703 the remainder of userspace will become appropriately inaccessible.
1705 config HW_PERF_EVENTS
1709 config SYS_SUPPORTS_HUGETLBFS
1713 config HAVE_ARCH_TRANSPARENT_HUGEPAGE
1717 config ARCH_WANT_GENERAL_HUGETLB
1720 config ARM_MODULE_PLTS
1721 bool "Use PLTs to allow module memory to spill over into vmalloc area"
1724 Allocate PLTs when loading modules so that jumps and calls whose
1725 targets are too far away for their relative offsets to be encoded
1726 in the instructions themselves can be bounced via veneers in the
1727 module's PLT. This allows modules to be allocated in the generic
1728 vmalloc area after the dedicated module memory area has been
1729 exhausted. The modules will use slightly more memory, but after
1730 rounding up to page size, the actual memory footprint is usually
1733 Say y if you are getting out of memory errors while loading modules
1737 config FORCE_MAX_ZONEORDER
1738 int "Maximum zone order"
1739 default "12" if SOC_AM33XX
1740 default "9" if SA1111 || ARCH_EFM32
1743 The kernel memory allocator divides physically contiguous memory
1744 blocks into "zones", where each zone is a power of two number of
1745 pages. This option selects the largest power of two that the kernel
1746 keeps in the memory allocator. If you need to allocate very large
1747 blocks of physically contiguous memory, then you may need to
1748 increase this value.
1750 This config option is actually maximum order plus one. For example,
1751 a value of 11 means that the largest free memory block is 2^10 pages.
1753 config ALIGNMENT_TRAP
1755 depends on CPU_CP15_MMU
1756 default y if !ARCH_EBSA110
1757 select HAVE_PROC_CPU if PROC_FS
1759 ARM processors cannot fetch/store information which is not
1760 naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1761 address divisible by 4. On 32-bit ARM processors, these non-aligned
1762 fetch/store instructions will be emulated in software if you say
1763 here, which has a severe performance impact. This is necessary for
1764 correct operation of some network protocols. With an IP-only
1765 configuration it is safe to say N, otherwise say Y.
1767 config UACCESS_WITH_MEMCPY
1768 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user()"
1770 default y if CPU_FEROCEON
1772 Implement faster copy_to_user and clear_user methods for CPU
1773 cores where a 8-word STM instruction give significantly higher
1774 memory write throughput than a sequence of individual 32bit stores.
1776 A possible side effect is a slight increase in scheduling latency
1777 between threads sharing the same address space if they invoke
1778 such copy operations with large buffers.
1780 However, if the CPU data cache is using a write-allocate mode,
1781 this option is unlikely to provide any performance gain.
1785 prompt "Enable seccomp to safely compute untrusted bytecode"
1787 This kernel feature is useful for number crunching applications
1788 that may need to compute untrusted bytecode during their
1789 execution. By using pipes or other transports made available to
1790 the process as file descriptors supporting the read/write
1791 syscalls, it's possible to isolate those applications in
1792 their own address space using seccomp. Once seccomp is
1793 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1794 and the task is only allowed to execute a few safe syscalls
1795 defined by each seccomp mode.
1808 bool "Xen guest support on ARM"
1809 depends on ARM && AEABI && OF
1810 depends on CPU_V7 && !CPU_V6
1811 depends on !GENERIC_ATOMIC64
1813 select ARCH_DMA_ADDR_T_64BIT
1817 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
1824 bool "Flattened Device Tree support"
1828 Include support for flattened device tree machine descriptions.
1831 bool "Support for the traditional ATAGS boot data passing" if USE_OF
1834 This is the traditional way of passing data to the kernel at boot
1835 time. If you are solely relying on the flattened device tree (or
1836 the ARM_ATAG_DTB_COMPAT option) then you may unselect this option
1837 to remove ATAGS support from your kernel binary. If unsure,
1840 config DEPRECATED_PARAM_STRUCT
1841 bool "Provide old way to pass kernel parameters"
1844 This was deprecated in 2001 and announced to live on for 5 years.
1845 Some old boot loaders still use this way.
1847 # Compressed boot loader in ROM. Yes, we really want to ask about
1848 # TEXT and BSS so we preserve their values in the config files.
1849 config ZBOOT_ROM_TEXT
1850 hex "Compressed ROM boot loader base address"
1853 The physical address at which the ROM-able zImage is to be
1854 placed in the target. Platforms which normally make use of
1855 ROM-able zImage formats normally set this to a suitable
1856 value in their defconfig file.
1858 If ZBOOT_ROM is not enabled, this has no effect.
1860 config ZBOOT_ROM_BSS
1861 hex "Compressed ROM boot loader BSS address"
1864 The base address of an area of read/write memory in the target
1865 for the ROM-able zImage which must be available while the
1866 decompressor is running. It must be large enough to hold the
1867 entire decompressed kernel plus an additional 128 KiB.
1868 Platforms which normally make use of ROM-able zImage formats
1869 normally set this to a suitable value in their defconfig file.
1871 If ZBOOT_ROM is not enabled, this has no effect.
1874 bool "Compressed boot loader in ROM/flash"
1875 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1876 depends on !ARM_APPENDED_DTB && !XIP_KERNEL && !AUTO_ZRELADDR
1878 Say Y here if you intend to execute your compressed kernel image
1879 (zImage) directly from ROM or flash. If unsure, say N.
1881 config ARM_APPENDED_DTB
1882 bool "Use appended device tree blob to zImage (EXPERIMENTAL)"
1885 With this option, the boot code will look for a device tree binary
1886 (DTB) appended to zImage
1887 (e.g. cat zImage <filename>.dtb > zImage_w_dtb).
1889 This is meant as a backward compatibility convenience for those
1890 systems with a bootloader that can't be upgraded to accommodate
1891 the documented boot protocol using a device tree.
1893 Beware that there is very little in terms of protection against
1894 this option being confused by leftover garbage in memory that might
1895 look like a DTB header after a reboot if no actual DTB is appended
1896 to zImage. Do not leave this option active in a production kernel
1897 if you don't intend to always append a DTB. Proper passing of the
1898 location into r2 of a bootloader provided DTB is always preferable
1901 config ARM_ATAG_DTB_COMPAT
1902 bool "Supplement the appended DTB with traditional ATAG information"
1903 depends on ARM_APPENDED_DTB
1905 Some old bootloaders can't be updated to a DTB capable one, yet
1906 they provide ATAGs with memory configuration, the ramdisk address,
1907 the kernel cmdline string, etc. Such information is dynamically
1908 provided by the bootloader and can't always be stored in a static
1909 DTB. To allow a device tree enabled kernel to be used with such
1910 bootloaders, this option allows zImage to extract the information
1911 from the ATAG list and store it at run time into the appended DTB.
1914 prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT
1915 default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1917 config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
1918 bool "Use bootloader kernel arguments if available"
1920 Uses the command-line options passed by the boot loader instead of
1921 the device tree bootargs property. If the boot loader doesn't provide
1922 any, the device tree bootargs property will be used.
1924 config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND
1925 bool "Extend with bootloader kernel arguments"
1927 The command-line arguments provided by the boot loader will be
1928 appended to the the device tree bootargs property.
1933 string "Default kernel command string"
1936 On some architectures (EBSA110 and CATS), there is currently no way
1937 for the boot loader to pass arguments to the kernel. For these
1938 architectures, you should supply some command-line options at build
1939 time by entering them here. As a minimum, you should specify the
1940 memory size and the root device (e.g., mem=64M root=/dev/nfs).
1943 prompt "Kernel command line type" if CMDLINE != ""
1944 default CMDLINE_FROM_BOOTLOADER
1947 config CMDLINE_FROM_BOOTLOADER
1948 bool "Use bootloader kernel arguments if available"
1950 Uses the command-line options passed by the boot loader. If
1951 the boot loader doesn't provide any, the default kernel command
1952 string provided in CMDLINE will be used.
1954 config CMDLINE_EXTEND
1955 bool "Extend bootloader kernel arguments"
1957 The command-line arguments provided by the boot loader will be
1958 appended to the default kernel command string.
1960 config CMDLINE_FORCE
1961 bool "Always use the default kernel command string"
1963 Always use the default kernel command string, even if the boot
1964 loader passes other arguments to the kernel.
1965 This is useful if you cannot or don't want to change the
1966 command-line options your boot loader passes to the kernel.
1970 bool "Kernel Execute-In-Place from ROM"
1971 depends on !ARM_LPAE && !ARCH_MULTIPLATFORM
1973 Execute-In-Place allows the kernel to run from non-volatile storage
1974 directly addressable by the CPU, such as NOR flash. This saves RAM
1975 space since the text section of the kernel is not loaded from flash
1976 to RAM. Read-write sections, such as the data section and stack,
1977 are still copied to RAM. The XIP kernel is not compressed since
1978 it has to run directly from flash, so it will take more space to
1979 store it. The flash address used to link the kernel object files,
1980 and for storing it, is configuration dependent. Therefore, if you
1981 say Y here, you must know the proper physical address where to
1982 store the kernel image depending on your own flash memory usage.
1984 Also note that the make target becomes "make xipImage" rather than
1985 "make zImage" or "make Image". The final kernel binary to put in
1986 ROM memory will be arch/arm/boot/xipImage.
1990 config XIP_PHYS_ADDR
1991 hex "XIP Kernel Physical Location"
1992 depends on XIP_KERNEL
1993 default "0x00080000"
1995 This is the physical address in your flash memory the kernel will
1996 be linked for and stored to. This address is dependent on your
2000 bool "Kexec system call (EXPERIMENTAL)"
2001 depends on (!SMP || PM_SLEEP_SMP)
2005 kexec is a system call that implements the ability to shutdown your
2006 current kernel, and to start another kernel. It is like a reboot
2007 but it is independent of the system firmware. And like a reboot
2008 you can start any kernel with it, not just Linux.
2010 It is an ongoing process to be certain the hardware in a machine
2011 is properly shutdown, so do not be surprised if this code does not
2012 initially work for you.
2015 bool "Export atags in procfs"
2016 depends on ATAGS && KEXEC
2019 Should the atags used to boot the kernel be exported in an "atags"
2020 file in procfs. Useful with kexec.
2023 bool "Build kdump crash kernel (EXPERIMENTAL)"
2025 Generate crash dump after being started by kexec. This should
2026 be normally only set in special crash dump kernels which are
2027 loaded in the main kernel with kexec-tools into a specially
2028 reserved region and then later executed after a crash by
2029 kdump/kexec. The crash dump kernel must be compiled to a
2030 memory address not used by the main kernel
2032 For more details see Documentation/kdump/kdump.txt
2034 config AUTO_ZRELADDR
2035 bool "Auto calculation of the decompressed kernel image address"
2037 ZRELADDR is the physical address where the decompressed kernel
2038 image will be placed. If AUTO_ZRELADDR is selected, the address
2039 will be determined at run-time by masking the current IP with
2040 0xf8000000. This assumes the zImage being placed in the first 128MB
2041 from start of memory.
2045 menu "CPU Power Management"
2047 source "drivers/cpufreq/Kconfig"
2049 source "drivers/cpuidle/Kconfig"
2053 menu "Floating point emulation"
2055 comment "At least one emulation must be selected"
2058 bool "NWFPE math emulation"
2059 depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL
2061 Say Y to include the NWFPE floating point emulator in the kernel.
2062 This is necessary to run most binaries. Linux does not currently
2063 support floating point hardware so you need to say Y here even if
2064 your machine has an FPA or floating point co-processor podule.
2066 You may say N here if you are going to load the Acorn FPEmulator
2067 early in the bootup.
2070 bool "Support extended precision"
2071 depends on FPE_NWFPE
2073 Say Y to include 80-bit support in the kernel floating-point
2074 emulator. Otherwise, only 32 and 64-bit support is compiled in.
2075 Note that gcc does not generate 80-bit operations by default,
2076 so in most cases this option only enlarges the size of the
2077 floating point emulator without any good reason.
2079 You almost surely want to say N here.
2082 bool "FastFPE math emulation (EXPERIMENTAL)"
2083 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3
2085 Say Y here to include the FAST floating point emulator in the kernel.
2086 This is an experimental much faster emulator which now also has full
2087 precision for the mantissa. It does not support any exceptions.
2088 It is very simple, and approximately 3-6 times faster than NWFPE.
2090 It should be sufficient for most programs. It may be not suitable
2091 for scientific calculations, but you have to check this for yourself.
2092 If you do not feel you need a faster FP emulation you should better
2096 bool "VFP-format floating point maths"
2097 depends on CPU_V6 || CPU_V6K || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
2099 Say Y to include VFP support code in the kernel. This is needed
2100 if your hardware includes a VFP unit.
2102 Please see <file:Documentation/arm/VFP/release-notes.txt> for
2103 release notes and additional status information.
2105 Say N if your target does not have VFP hardware.
2113 bool "Advanced SIMD (NEON) Extension support"
2114 depends on VFPv3 && CPU_V7
2116 Say Y to include support code for NEON, the ARMv7 Advanced SIMD
2119 config KERNEL_MODE_NEON
2120 bool "Support for NEON in kernel mode"
2121 depends on NEON && AEABI
2123 Say Y to include support for NEON in kernel mode.
2127 menu "Userspace binary formats"
2129 source "fs/Kconfig.binfmt"
2133 menu "Power management options"
2135 source "kernel/power/Kconfig"
2137 config ARCH_SUSPEND_POSSIBLE
2138 depends on CPU_ARM920T || CPU_ARM926T || CPU_FEROCEON || CPU_SA1100 || \
2139 CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7M || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK
2142 config ARM_CPU_SUSPEND
2145 config ARCH_HIBERNATION_POSSIBLE
2148 default y if ARCH_SUSPEND_POSSIBLE
2152 source "net/Kconfig"
2154 source "drivers/Kconfig"
2156 source "drivers/firmware/Kconfig"
2160 source "arch/arm/Kconfig.debug"
2162 source "security/Kconfig"
2164 source "crypto/Kconfig"
2166 source "arch/arm/crypto/Kconfig"
2169 source "lib/Kconfig"
2171 source "arch/arm/kvm/Kconfig"