4 select ARCH_BINFMT_ELF_RANDOMIZE_PIE
5 select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
6 select ARCH_HAVE_CUSTOM_GPIO_H
7 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
8 select ARCH_WANT_IPC_PARSE_VERSION
9 select BUILDTIME_EXTABLE_SORT if MMU
10 select CPU_PM if (SUSPEND || CPU_IDLE)
11 select DCACHE_WORD_ACCESS if (CPU_V6 || CPU_V6K || CPU_V7) && !CPU_BIG_ENDIAN && MMU
12 select GENERIC_ATOMIC64 if (CPU_V6 || !CPU_32v6K || !AEABI)
13 select GENERIC_CLOCKEVENTS_BROADCAST if SMP
14 select GENERIC_IRQ_PROBE
15 select GENERIC_IRQ_SHOW
16 select GENERIC_PCI_IOMAP
17 select GENERIC_SMP_IDLE_THREAD
18 select GENERIC_STRNCPY_FROM_USER
19 select GENERIC_STRNLEN_USER
20 select HARDIRQS_SW_RESEND
22 select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL
24 select HAVE_ARCH_SECCOMP_FILTER
25 select HAVE_ARCH_TRACEHOOK
27 select HAVE_C_RECORDMCOUNT
28 select HAVE_DEBUG_KMEMLEAK
29 select HAVE_DMA_API_DEBUG
31 select HAVE_DMA_CONTIGUOUS if MMU
32 select HAVE_DYNAMIC_FTRACE if (!XIP_KERNEL)
33 select HAVE_FTRACE_MCOUNT_RECORD if (!XIP_KERNEL)
34 select HAVE_FUNCTION_GRAPH_TRACER if (!THUMB2_KERNEL)
35 select HAVE_FUNCTION_TRACER if (!XIP_KERNEL)
36 select HAVE_GENERIC_DMA_COHERENT
37 select HAVE_GENERIC_HARDIRQS
38 select HAVE_HW_BREAKPOINT if (PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7))
39 select HAVE_IDE if PCI || ISA || PCMCIA
40 select HAVE_KERNEL_GZIP
41 select HAVE_KERNEL_LZMA
42 select HAVE_KERNEL_LZO
44 select HAVE_KPROBES if !XIP_KERNEL
45 select HAVE_KRETPROBES if (HAVE_KPROBES)
47 select HAVE_OPROFILE if (HAVE_PERF_EVENTS)
48 select HAVE_PERF_EVENTS
49 select HAVE_REGS_AND_STACK_ACCESS_API
50 select HAVE_SYSCALL_TRACEPOINTS
53 select PERF_USE_VMALLOC
55 select SYS_SUPPORTS_APM_EMULATION
56 select HAVE_MOD_ARCH_SPECIFIC if ARM_UNWIND
57 select MODULES_USE_ELF_REL
58 select CLONE_BACKWARDS
59 select OLD_SIGSUSPEND3
62 The ARM series is a line of low-power-consumption RISC chip designs
63 licensed by ARM Ltd and targeted at embedded applications and
64 handhelds such as the Compaq IPAQ. ARM-based PCs are no longer
65 manufactured, but legacy ARM-based PC hardware remains popular in
66 Europe. There is an ARM Linux project with a web page at
67 <http://www.arm.linux.org.uk/>.
69 config ARM_HAS_SG_CHAIN
72 config NEED_SG_DMA_LENGTH
75 config ARM_DMA_USE_IOMMU
77 select ARM_HAS_SG_CHAIN
78 select NEED_SG_DMA_LENGTH
82 config ARM_DMA_IOMMU_ALIGNMENT
83 int "Maximum PAGE_SIZE order of alignment for DMA IOMMU buffers"
87 DMA mapping framework by default aligns all buffers to the smallest
88 PAGE_SIZE order which is greater than or equal to the requested buffer
89 size. This works well for buffers up to a few hundreds kilobytes, but
90 for larger buffers it just a waste of address space. Drivers which has
91 relatively small addressing window (like 64Mib) might run out of
92 virtual space with just a few allocations.
94 With this parameter you can specify the maximum PAGE_SIZE order for
95 DMA IOMMU buffers. Larger buffers will be aligned only to this
96 specified order. The order is expressed as a power of two multiplied
104 config MIGHT_HAVE_PCI
107 config SYS_SUPPORTS_APM_EMULATION
115 select GENERIC_ALLOCATOR
126 The Extended Industry Standard Architecture (EISA) bus was
127 developed as an open alternative to the IBM MicroChannel bus.
129 The EISA bus provided some of the features of the IBM MicroChannel
130 bus while maintaining backward compatibility with cards made for
131 the older ISA bus. The EISA bus saw limited use between 1988 and
132 1995 when it was made obsolete by the PCI bus.
134 Say Y here if you are building a kernel for an EISA-based machine.
141 config STACKTRACE_SUPPORT
145 config HAVE_LATENCYTOP_SUPPORT
150 config LOCKDEP_SUPPORT
154 config TRACE_IRQFLAGS_SUPPORT
158 config RWSEM_GENERIC_SPINLOCK
162 config RWSEM_XCHGADD_ALGORITHM
165 config ARCH_HAS_ILOG2_U32
168 config ARCH_HAS_ILOG2_U64
171 config ARCH_HAS_CPUFREQ
174 Internal node to signify that the ARCH has CPUFREQ support
175 and that the relevant menu configurations are displayed for
178 config GENERIC_HWEIGHT
182 config GENERIC_CALIBRATE_DELAY
186 config ARCH_MAY_HAVE_PC_FDC
192 config NEED_DMA_MAP_STATE
195 config ARCH_HAS_DMA_SET_COHERENT_MASK
198 config GENERIC_ISA_DMA
204 config NEED_RET_TO_USER
212 default 0xffff0000 if MMU || CPU_HIGH_VECTOR
213 default DRAM_BASE if REMAP_VECTORS_TO_RAM
216 The base address of exception vectors.
218 config ARM_PATCH_PHYS_VIRT
219 bool "Patch physical to virtual translations at runtime" if EMBEDDED
221 depends on !XIP_KERNEL && MMU
222 depends on !ARCH_REALVIEW || !SPARSEMEM
224 Patch phys-to-virt and virt-to-phys translation functions at
225 boot and module load time according to the position of the
226 kernel in system memory.
228 This can only be used with non-XIP MMU kernels where the base
229 of physical memory is at a 16MB boundary.
231 Only disable this option if you know that you do not require
232 this feature (eg, building a kernel for a single machine) and
233 you need to shrink the kernel to the minimal size.
235 config NEED_MACH_GPIO_H
238 Select this when mach/gpio.h is required to provide special
239 definitions for this platform. The need for mach/gpio.h should
240 be avoided when possible.
242 config NEED_MACH_IO_H
245 Select this when mach/io.h is required to provide special
246 definitions for this platform. The need for mach/io.h should
247 be avoided when possible.
249 config NEED_MACH_MEMORY_H
252 Select this when mach/memory.h is required to provide special
253 definitions for this platform. The need for mach/memory.h should
254 be avoided when possible.
257 hex "Physical address of main memory" if MMU
258 depends on !ARM_PATCH_PHYS_VIRT && !NEED_MACH_MEMORY_H
259 default DRAM_BASE if !MMU
261 Please provide the physical address corresponding to the
262 location of main memory in your system.
268 source "init/Kconfig"
270 source "kernel/Kconfig.freezer"
275 bool "MMU-based Paged Memory Management Support"
278 Select if you want MMU-based virtualised addressing space
279 support by paged memory management. If unsure, say 'Y'.
282 # The "ARM system type" choice list is ordered alphabetically by option
283 # text. Please add new entries in the option alphabetic order.
286 prompt "ARM system type"
287 default ARCH_VERSATILE if !MMU
288 default ARCH_MULTIPLATFORM if MMU
290 config ARCH_MULTIPLATFORM
291 bool "Allow multiple platforms to be selected"
293 select ARM_PATCH_PHYS_VIRT
296 select MULTI_IRQ_HANDLER
300 config ARCH_INTEGRATOR
301 bool "ARM Ltd. Integrator family"
302 select ARCH_HAS_CPUFREQ
305 select COMMON_CLK_VERSATILE
306 select GENERIC_CLOCKEVENTS
309 select MULTI_IRQ_HANDLER
310 select NEED_MACH_MEMORY_H
311 select PLAT_VERSATILE
313 select VERSATILE_FPGA_IRQ
315 Support for ARM's Integrator platform.
318 bool "ARM Ltd. RealView family"
319 select ARCH_WANT_OPTIONAL_GPIOLIB
321 select ARM_TIMER_SP804
323 select COMMON_CLK_VERSATILE
324 select GENERIC_CLOCKEVENTS
325 select GPIO_PL061 if GPIOLIB
327 select NEED_MACH_MEMORY_H
328 select PLAT_VERSATILE
329 select PLAT_VERSATILE_CLCD
331 This enables support for ARM Ltd RealView boards.
333 config ARCH_VERSATILE
334 bool "ARM Ltd. Versatile family"
335 select ARCH_WANT_OPTIONAL_GPIOLIB
337 select ARM_TIMER_SP804
340 select GENERIC_CLOCKEVENTS
341 select HAVE_MACH_CLKDEV
343 select PLAT_VERSATILE
344 select PLAT_VERSATILE_CLCD
345 select PLAT_VERSATILE_CLOCK
346 select VERSATILE_FPGA_IRQ
348 This enables support for ARM Ltd Versatile board.
352 select ARCH_REQUIRE_GPIOLIB
356 select NEED_MACH_GPIO_H
357 select NEED_MACH_IO_H if PCCARD
359 select PINCTRL_AT91 if USE_OF
361 This enables support for systems based on Atmel
362 AT91RM9200 and AT91SAM9* processors.
365 bool "Broadcom BCM2835 family"
366 select ARCH_REQUIRE_GPIOLIB
368 select ARM_ERRATA_411920
369 select ARM_TIMER_SP804
374 select GENERIC_CLOCKEVENTS
375 select MULTI_IRQ_HANDLER
377 select PINCTRL_BCM2835
381 This enables support for the Broadcom BCM2835 SoC. This SoC is
382 use in the Raspberry Pi, and Roku 2 devices.
385 bool "Cavium Networks CNS3XXX family"
388 select GENERIC_CLOCKEVENTS
389 select MIGHT_HAVE_CACHE_L2X0
390 select MIGHT_HAVE_PCI
391 select PCI_DOMAINS if PCI
393 Support for Cavium Networks CNS3XXX platform.
396 bool "Cirrus Logic CLPS711x/EP721x/EP731x-based"
397 select ARCH_REQUIRE_GPIOLIB
402 select GENERIC_CLOCKEVENTS
403 select MULTI_IRQ_HANDLER
404 select NEED_MACH_MEMORY_H
407 Support for Cirrus Logic 711x/721x/731x based boards.
410 bool "Cortina Systems Gemini"
411 select ARCH_REQUIRE_GPIOLIB
412 select ARCH_USES_GETTIMEOFFSET
415 Support for the Cortina Systems Gemini family SoCs
419 select ARCH_REQUIRE_GPIOLIB
422 select GENERIC_CLOCKEVENTS
423 select GENERIC_IRQ_CHIP
424 select MIGHT_HAVE_CACHE_L2X0
430 Support for CSR SiRFprimaII/Marco/Polo platforms
434 select ARCH_USES_GETTIMEOFFSET
437 select NEED_MACH_IO_H
438 select NEED_MACH_MEMORY_H
441 This is an evaluation board for the StrongARM processor available
442 from Digital. It has limited hardware on-board, including an
443 Ethernet interface, two PCMCIA sockets, two serial ports and a
448 select ARCH_HAS_HOLES_MEMORYMODEL
449 select ARCH_REQUIRE_GPIOLIB
450 select ARCH_USES_GETTIMEOFFSET
455 select NEED_MACH_MEMORY_H
457 This enables support for the Cirrus EP93xx series of CPUs.
459 config ARCH_FOOTBRIDGE
463 select GENERIC_CLOCKEVENTS
465 select NEED_MACH_IO_H if !MMU
466 select NEED_MACH_MEMORY_H
468 Support for systems based on the DC21285 companion chip
469 ("FootBridge"), such as the Simtec CATS and the Rebel NetWinder.
472 bool "Freescale MXS-based"
473 select ARCH_REQUIRE_GPIOLIB
477 select GENERIC_CLOCKEVENTS
478 select HAVE_CLK_PREPARE
479 select MULTI_IRQ_HANDLER
484 Support for Freescale MXS-based family of processors
487 bool "Hilscher NetX based"
491 select GENERIC_CLOCKEVENTS
493 This enables support for systems based on the Hilscher NetX Soc
496 bool "Hynix HMS720x-based"
497 select ARCH_USES_GETTIMEOFFSET
501 This enables support for systems based on the Hynix HMS720x
506 select ARCH_SUPPORTS_MSI
508 select NEED_MACH_MEMORY_H
509 select NEED_RET_TO_USER
514 Support for Intel's IOP13XX (XScale) family of processors.
519 select ARCH_REQUIRE_GPIOLIB
521 select NEED_MACH_GPIO_H
522 select NEED_RET_TO_USER
526 Support for Intel's 80219 and IOP32X (XScale) family of
532 select ARCH_REQUIRE_GPIOLIB
534 select NEED_MACH_GPIO_H
535 select NEED_RET_TO_USER
539 Support for Intel's IOP33X (XScale) family of processors.
544 select ARCH_HAS_DMA_SET_COHERENT_MASK
545 select ARCH_REQUIRE_GPIOLIB
548 select DMABOUNCE if PCI
549 select GENERIC_CLOCKEVENTS
550 select MIGHT_HAVE_PCI
551 select NEED_MACH_IO_H
553 Support for Intel's IXP4XX (XScale) family of processors.
557 select ARCH_REQUIRE_GPIOLIB
559 select GENERIC_CLOCKEVENTS
560 select MIGHT_HAVE_PCI
563 select PLAT_ORION_LEGACY
564 select USB_ARCH_HAS_EHCI
566 Support for the Marvell Dove SoC 88AP510
569 bool "Marvell Kirkwood"
570 select ARCH_REQUIRE_GPIOLIB
572 select GENERIC_CLOCKEVENTS
576 select PINCTRL_KIRKWOOD
577 select PLAT_ORION_LEGACY
579 Support for the following Marvell Kirkwood series SoCs:
580 88F6180, 88F6192 and 88F6281.
583 bool "Marvell MV78xx0"
584 select ARCH_REQUIRE_GPIOLIB
586 select GENERIC_CLOCKEVENTS
588 select PLAT_ORION_LEGACY
590 Support for the following Marvell MV78xx0 series SoCs:
596 select ARCH_REQUIRE_GPIOLIB
598 select GENERIC_CLOCKEVENTS
600 select PLAT_ORION_LEGACY
602 Support for the following Marvell Orion 5x series SoCs:
603 Orion-1 (5181), Orion-VoIP (5181L), Orion-NAS (5182),
604 Orion-2 (5281), Orion-1-90 (6183).
607 bool "Marvell PXA168/910/MMP2"
609 select ARCH_REQUIRE_GPIOLIB
611 select GENERIC_ALLOCATOR
612 select GENERIC_CLOCKEVENTS
615 select NEED_MACH_GPIO_H
620 Support for Marvell's PXA168/PXA910(MMP) and MMP2 processor line.
623 bool "Micrel/Kendin KS8695"
624 select ARCH_REQUIRE_GPIOLIB
627 select GENERIC_CLOCKEVENTS
628 select NEED_MACH_MEMORY_H
630 Support for Micrel/Kendin KS8695 "Centaur" (ARM922T) based
631 System-on-Chip devices.
634 bool "Nuvoton W90X900 CPU"
635 select ARCH_REQUIRE_GPIOLIB
639 select GENERIC_CLOCKEVENTS
641 Support for Nuvoton (Winbond logic dept.) ARM9 processor,
642 At present, the w90x900 has been renamed nuc900, regarding
643 the ARM series product line, you can login the following
644 link address to know more.
646 <http://www.nuvoton.com/hq/enu/ProductAndSales/ProductLines/
647 ConsumerElectronicsIC/ARMMicrocontroller/ARMMicrocontroller>
651 select ARCH_REQUIRE_GPIOLIB
656 select GENERIC_CLOCKEVENTS
659 select USB_ARCH_HAS_OHCI
662 Support for the NXP LPC32XX family of processors
666 select ARCH_HAS_CPUFREQ
667 select ARCH_REQUIRE_GPIOLIB
672 select GENERIC_CLOCKEVENTS
675 select MIGHT_HAVE_CACHE_L2X0
679 This enables support for NVIDIA Tegra based systems (Tegra APX,
680 Tegra 6xx and Tegra 2 series).
683 bool "PXA2xx/PXA3xx-based"
685 select ARCH_HAS_CPUFREQ
687 select ARCH_REQUIRE_GPIOLIB
688 select ARM_CPU_SUSPEND if PM
692 select GENERIC_CLOCKEVENTS
695 select MULTI_IRQ_HANDLER
696 select NEED_MACH_GPIO_H
700 Support for Intel/Marvell's PXA2xx/PXA3xx processor line.
704 select ARCH_REQUIRE_GPIOLIB
706 select GENERIC_CLOCKEVENTS
709 Support for Qualcomm MSM/QSD based systems. This runs on the
710 apps processor of the MSM/QSD and depends on a shared memory
711 interface to the modem processor which runs the baseband
712 stack and controls some vital subsystems
713 (clock and power control, etc).
716 bool "Renesas SH-Mobile / R-Mobile"
718 select GENERIC_CLOCKEVENTS
720 select HAVE_MACH_CLKDEV
722 select MIGHT_HAVE_CACHE_L2X0
723 select MULTI_IRQ_HANDLER
724 select NEED_MACH_MEMORY_H
727 select PM_GENERIC_DOMAINS if PM
730 Support for Renesas's SH-Mobile and R-Mobile ARM platforms.
735 select ARCH_MAY_HAVE_PC_FDC
736 select ARCH_SPARSEMEM_ENABLE
737 select ARCH_USES_GETTIMEOFFSET
740 select HAVE_PATA_PLATFORM
742 select NEED_MACH_IO_H
743 select NEED_MACH_MEMORY_H
747 On the Acorn Risc-PC, Linux can support the internal IDE disk and
748 CD-ROM interface, serial and parallel port, and the floppy drive.
752 select ARCH_HAS_CPUFREQ
754 select ARCH_REQUIRE_GPIOLIB
755 select ARCH_SPARSEMEM_ENABLE
760 select GENERIC_CLOCKEVENTS
763 select NEED_MACH_GPIO_H
764 select NEED_MACH_MEMORY_H
767 Support for StrongARM 11x0 based boards.
770 bool "Samsung S3C24XX SoCs"
771 select ARCH_HAS_CPUFREQ
772 select ARCH_USES_GETTIMEOFFSET
775 select HAVE_S3C2410_I2C if I2C
776 select HAVE_S3C2410_WATCHDOG if WATCHDOG
777 select HAVE_S3C_RTC if RTC_CLASS
778 select NEED_MACH_GPIO_H
779 select NEED_MACH_IO_H
781 Samsung S3C2410, S3C2412, S3C2413, S3C2416, S3C2440, S3C2442, S3C2443
782 and S3C2450 SoCs based systems, such as the Simtec Electronics BAST
783 (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or the
784 Samsung SMDK2410 development board (and derivatives).
787 bool "Samsung S3C64XX"
788 select ARCH_HAS_CPUFREQ
789 select ARCH_REQUIRE_GPIOLIB
790 select ARCH_USES_GETTIMEOFFSET
795 select HAVE_S3C2410_I2C if I2C
796 select HAVE_S3C2410_WATCHDOG if WATCHDOG
798 select NEED_MACH_GPIO_H
802 select S3C_GPIO_TRACK
803 select SAMSUNG_CLKSRC
804 select SAMSUNG_GPIOLIB_4BIT
805 select SAMSUNG_IRQ_VIC_TIMER
806 select USB_ARCH_HAS_OHCI
808 Samsung S3C64XX series based systems
811 bool "Samsung S5P6440 S5P6450"
815 select GENERIC_CLOCKEVENTS
817 select HAVE_S3C2410_I2C if I2C
818 select HAVE_S3C2410_WATCHDOG if WATCHDOG
819 select HAVE_S3C_RTC if RTC_CLASS
820 select NEED_MACH_GPIO_H
822 Samsung S5P64X0 CPU based systems, such as the Samsung SMDK6440,
826 bool "Samsung S5PC100"
827 select ARCH_USES_GETTIMEOFFSET
831 select HAVE_S3C2410_I2C if I2C
832 select HAVE_S3C2410_WATCHDOG if WATCHDOG
833 select HAVE_S3C_RTC if RTC_CLASS
834 select NEED_MACH_GPIO_H
836 Samsung S5PC100 series based systems
839 bool "Samsung S5PV210/S5PC110"
840 select ARCH_HAS_CPUFREQ
841 select ARCH_HAS_HOLES_MEMORYMODEL
842 select ARCH_SPARSEMEM_ENABLE
846 select GENERIC_CLOCKEVENTS
848 select HAVE_S3C2410_I2C if I2C
849 select HAVE_S3C2410_WATCHDOG if WATCHDOG
850 select HAVE_S3C_RTC if RTC_CLASS
851 select NEED_MACH_GPIO_H
852 select NEED_MACH_MEMORY_H
854 Samsung S5PV210/S5PC110 series based systems
857 bool "Samsung EXYNOS"
858 select ARCH_HAS_CPUFREQ
859 select ARCH_HAS_HOLES_MEMORYMODEL
860 select ARCH_SPARSEMEM_ENABLE
863 select GENERIC_CLOCKEVENTS
865 select HAVE_S3C2410_I2C if I2C
866 select HAVE_S3C2410_WATCHDOG if WATCHDOG
867 select HAVE_S3C_RTC if RTC_CLASS
868 select NEED_MACH_GPIO_H
869 select NEED_MACH_MEMORY_H
871 Support for SAMSUNG's EXYNOS SoCs (EXYNOS4/5)
875 select ARCH_USES_GETTIMEOFFSET
879 select NEED_MACH_MEMORY_H
884 Support for the StrongARM based Digital DNARD machine, also known
885 as "Shark" (<http://www.shark-linux.de/shark.html>).
888 bool "ST-Ericsson U300 Series"
890 select ARCH_REQUIRE_GPIOLIB
892 select ARM_PATCH_PHYS_VIRT
898 select GENERIC_CLOCKEVENTS
902 Support for ST-Ericsson U300 series mobile platforms.
905 bool "ST-Ericsson U8500 Series"
907 select ARCH_HAS_CPUFREQ
908 select ARCH_REQUIRE_GPIOLIB
912 select GENERIC_CLOCKEVENTS
914 select MIGHT_HAVE_CACHE_L2X0
917 Support for ST-Ericsson's Ux500 architecture
920 bool "STMicroelectronics Nomadik"
921 select ARCH_REQUIRE_GPIOLIB
924 select CLKSRC_NOMADIK_MTU
927 select GENERIC_CLOCKEVENTS
928 select MIGHT_HAVE_CACHE_L2X0
931 select PINCTRL_STN8815
934 Support for the Nomadik platform by ST-Ericsson
938 select ARCH_HAS_CPUFREQ
939 select ARCH_REQUIRE_GPIOLIB
944 select GENERIC_CLOCKEVENTS
947 Support for ST's SPEAr platform (SPEAr3xx, SPEAr6xx and SPEAr13xx).
951 select ARCH_HAS_HOLES_MEMORYMODEL
952 select ARCH_REQUIRE_GPIOLIB
954 select GENERIC_ALLOCATOR
955 select GENERIC_CLOCKEVENTS
956 select GENERIC_IRQ_CHIP
958 select NEED_MACH_GPIO_H
962 Support for TI's DaVinci platform.
967 select ARCH_HAS_CPUFREQ
968 select ARCH_HAS_HOLES_MEMORYMODEL
970 select ARCH_REQUIRE_GPIOLIB
973 select GENERIC_CLOCKEVENTS
974 select GENERIC_IRQ_CHIP
978 select NEED_MACH_IO_H if PCCARD
979 select NEED_MACH_MEMORY_H
981 Support for older TI OMAP1 (omap7xx, omap15xx or omap16xx)
985 menu "Multiple platform selection"
986 depends on ARCH_MULTIPLATFORM
988 comment "CPU Core family selection"
991 bool "ARMv4 based platforms (FA526, StrongARM)"
992 depends on !ARCH_MULTI_V6_V7
993 select ARCH_MULTI_V4_V5
995 config ARCH_MULTI_V4T
996 bool "ARMv4T based platforms (ARM720T, ARM920T, ...)"
997 depends on !ARCH_MULTI_V6_V7
998 select ARCH_MULTI_V4_V5
1000 config ARCH_MULTI_V5
1001 bool "ARMv5 based platforms (ARM926T, XSCALE, PJ1, ...)"
1002 depends on !ARCH_MULTI_V6_V7
1003 select ARCH_MULTI_V4_V5
1005 config ARCH_MULTI_V4_V5
1008 config ARCH_MULTI_V6
1009 bool "ARMv6 based platforms (ARM11)"
1010 select ARCH_MULTI_V6_V7
1013 config ARCH_MULTI_V7
1014 bool "ARMv7 based platforms (Cortex-A, PJ4, Scorpion, Krait)"
1016 select ARCH_MULTI_V6_V7
1017 select ARCH_VEXPRESS
1020 config ARCH_MULTI_V6_V7
1023 config ARCH_MULTI_CPU_AUTO
1024 def_bool !(ARCH_MULTI_V4 || ARCH_MULTI_V4T || ARCH_MULTI_V6_V7)
1025 select ARCH_MULTI_V5
1030 # This is sorted alphabetically by mach-* pathname. However, plat-*
1031 # Kconfigs may be included either alphabetically (according to the
1032 # plat- suffix) or along side the corresponding mach-* source.
1034 source "arch/arm/mach-mvebu/Kconfig"
1036 source "arch/arm/mach-at91/Kconfig"
1038 source "arch/arm/mach-bcm/Kconfig"
1040 source "arch/arm/mach-clps711x/Kconfig"
1042 source "arch/arm/mach-cns3xxx/Kconfig"
1044 source "arch/arm/mach-davinci/Kconfig"
1046 source "arch/arm/mach-dove/Kconfig"
1048 source "arch/arm/mach-ep93xx/Kconfig"
1050 source "arch/arm/mach-footbridge/Kconfig"
1052 source "arch/arm/mach-gemini/Kconfig"
1054 source "arch/arm/mach-h720x/Kconfig"
1056 source "arch/arm/mach-highbank/Kconfig"
1058 source "arch/arm/mach-integrator/Kconfig"
1060 source "arch/arm/mach-iop32x/Kconfig"
1062 source "arch/arm/mach-iop33x/Kconfig"
1064 source "arch/arm/mach-iop13xx/Kconfig"
1066 source "arch/arm/mach-ixp4xx/Kconfig"
1068 source "arch/arm/mach-kirkwood/Kconfig"
1070 source "arch/arm/mach-ks8695/Kconfig"
1072 source "arch/arm/mach-msm/Kconfig"
1074 source "arch/arm/mach-mv78xx0/Kconfig"
1076 source "arch/arm/mach-imx/Kconfig"
1078 source "arch/arm/mach-mxs/Kconfig"
1080 source "arch/arm/mach-netx/Kconfig"
1082 source "arch/arm/mach-nomadik/Kconfig"
1084 source "arch/arm/plat-omap/Kconfig"
1086 source "arch/arm/mach-omap1/Kconfig"
1088 source "arch/arm/mach-omap2/Kconfig"
1090 source "arch/arm/mach-orion5x/Kconfig"
1092 source "arch/arm/mach-picoxcell/Kconfig"
1094 source "arch/arm/mach-pxa/Kconfig"
1095 source "arch/arm/plat-pxa/Kconfig"
1097 source "arch/arm/mach-mmp/Kconfig"
1099 source "arch/arm/mach-realview/Kconfig"
1101 source "arch/arm/mach-sa1100/Kconfig"
1103 source "arch/arm/plat-samsung/Kconfig"
1105 source "arch/arm/mach-socfpga/Kconfig"
1107 source "arch/arm/plat-spear/Kconfig"
1109 source "arch/arm/mach-s3c24xx/Kconfig"
1112 source "arch/arm/mach-s3c64xx/Kconfig"
1115 source "arch/arm/mach-s5p64x0/Kconfig"
1117 source "arch/arm/mach-s5pc100/Kconfig"
1119 source "arch/arm/mach-s5pv210/Kconfig"
1121 source "arch/arm/mach-exynos/Kconfig"
1123 source "arch/arm/mach-shmobile/Kconfig"
1125 source "arch/arm/mach-sunxi/Kconfig"
1127 source "arch/arm/mach-prima2/Kconfig"
1129 source "arch/arm/mach-tegra/Kconfig"
1131 source "arch/arm/mach-u300/Kconfig"
1133 source "arch/arm/mach-ux500/Kconfig"
1135 source "arch/arm/mach-versatile/Kconfig"
1137 source "arch/arm/mach-vexpress/Kconfig"
1138 source "arch/arm/plat-versatile/Kconfig"
1140 source "arch/arm/mach-virt/Kconfig"
1142 source "arch/arm/mach-vt8500/Kconfig"
1144 source "arch/arm/mach-w90x900/Kconfig"
1146 source "arch/arm/mach-zynq/Kconfig"
1148 # Definitions to make life easier
1154 select GENERIC_CLOCKEVENTS
1160 select GENERIC_IRQ_CHIP
1163 config PLAT_ORION_LEGACY
1170 config PLAT_VERSATILE
1173 config ARM_TIMER_SP804
1176 select HAVE_SCHED_CLOCK
1178 source arch/arm/mm/Kconfig
1182 default 16 if ARCH_EP93XX
1186 bool "Enable iWMMXt support" if !CPU_PJ4
1187 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4
1188 default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4
1190 Enable support for iWMMXt context switching at run time if
1191 running on a CPU that supports it.
1195 depends on CPU_XSCALE
1198 config MULTI_IRQ_HANDLER
1201 Allow each machine to specify it's own IRQ handler at run time.
1204 source "arch/arm/Kconfig-nommu"
1207 config ARM_ERRATA_326103
1208 bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory"
1211 Executing a SWP instruction to read-only memory does not set bit 11
1212 of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to
1213 treat the access as a read, preventing a COW from occurring and
1214 causing the faulting task to livelock.
1216 config ARM_ERRATA_411920
1217 bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
1218 depends on CPU_V6 || CPU_V6K
1220 Invalidation of the Instruction Cache operation can
1221 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
1222 It does not affect the MPCore. This option enables the ARM Ltd.
1223 recommended workaround.
1225 config ARM_ERRATA_430973
1226 bool "ARM errata: Stale prediction on replaced interworking branch"
1229 This option enables the workaround for the 430973 Cortex-A8
1230 (r1p0..r1p2) erratum. If a code sequence containing an ARM/Thumb
1231 interworking branch is replaced with another code sequence at the
1232 same virtual address, whether due to self-modifying code or virtual
1233 to physical address re-mapping, Cortex-A8 does not recover from the
1234 stale interworking branch prediction. This results in Cortex-A8
1235 executing the new code sequence in the incorrect ARM or Thumb state.
1236 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
1237 and also flushes the branch target cache at every context switch.
1238 Note that setting specific bits in the ACTLR register may not be
1239 available in non-secure mode.
1241 config ARM_ERRATA_458693
1242 bool "ARM errata: Processor deadlock when a false hazard is created"
1244 depends on !ARCH_MULTIPLATFORM
1246 This option enables the workaround for the 458693 Cortex-A8 (r2p0)
1247 erratum. For very specific sequences of memory operations, it is
1248 possible for a hazard condition intended for a cache line to instead
1249 be incorrectly associated with a different cache line. This false
1250 hazard might then cause a processor deadlock. The workaround enables
1251 the L1 caching of the NEON accesses and disables the PLD instruction
1252 in the ACTLR register. Note that setting specific bits in the ACTLR
1253 register may not be available in non-secure mode.
1255 config ARM_ERRATA_460075
1256 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
1258 depends on !ARCH_MULTIPLATFORM
1260 This option enables the workaround for the 460075 Cortex-A8 (r2p0)
1261 erratum. Any asynchronous access to the L2 cache may encounter a
1262 situation in which recent store transactions to the L2 cache are lost
1263 and overwritten with stale memory contents from external memory. The
1264 workaround disables the write-allocate mode for the L2 cache via the
1265 ACTLR register. Note that setting specific bits in the ACTLR register
1266 may not be available in non-secure mode.
1268 config ARM_ERRATA_742230
1269 bool "ARM errata: DMB operation may be faulty"
1270 depends on CPU_V7 && SMP
1271 depends on !ARCH_MULTIPLATFORM
1273 This option enables the workaround for the 742230 Cortex-A9
1274 (r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction
1275 between two write operations may not ensure the correct visibility
1276 ordering of the two writes. This workaround sets a specific bit in
1277 the diagnostic register of the Cortex-A9 which causes the DMB
1278 instruction to behave as a DSB, ensuring the correct behaviour of
1281 config ARM_ERRATA_742231
1282 bool "ARM errata: Incorrect hazard handling in the SCU may lead to data corruption"
1283 depends on CPU_V7 && SMP
1284 depends on !ARCH_MULTIPLATFORM
1286 This option enables the workaround for the 742231 Cortex-A9
1287 (r2p0..r2p2) erratum. Under certain conditions, specific to the
1288 Cortex-A9 MPCore micro-architecture, two CPUs working in SMP mode,
1289 accessing some data located in the same cache line, may get corrupted
1290 data due to bad handling of the address hazard when the line gets
1291 replaced from one of the CPUs at the same time as another CPU is
1292 accessing it. This workaround sets specific bits in the diagnostic
1293 register of the Cortex-A9 which reduces the linefill issuing
1294 capabilities of the processor.
1296 config PL310_ERRATA_588369
1297 bool "PL310 errata: Clean & Invalidate maintenance operations do not invalidate clean lines"
1298 depends on CACHE_L2X0
1300 The PL310 L2 cache controller implements three types of Clean &
1301 Invalidate maintenance operations: by Physical Address
1302 (offset 0x7F0), by Index/Way (0x7F8) and by Way (0x7FC).
1303 They are architecturally defined to behave as the execution of a
1304 clean operation followed immediately by an invalidate operation,
1305 both performing to the same memory location. This functionality
1306 is not correctly implemented in PL310 as clean lines are not
1307 invalidated as a result of these operations.
1309 config ARM_ERRATA_720789
1310 bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID"
1313 This option enables the workaround for the 720789 Cortex-A9 (prior to
1314 r2p0) erratum. A faulty ASID can be sent to the other CPUs for the
1315 broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS.
1316 As a consequence of this erratum, some TLB entries which should be
1317 invalidated are not, resulting in an incoherency in the system page
1318 tables. The workaround changes the TLB flushing routines to invalidate
1319 entries regardless of the ASID.
1321 config PL310_ERRATA_727915
1322 bool "PL310 errata: Background Clean & Invalidate by Way operation can cause data corruption"
1323 depends on CACHE_L2X0
1325 PL310 implements the Clean & Invalidate by Way L2 cache maintenance
1326 operation (offset 0x7FC). This operation runs in background so that
1327 PL310 can handle normal accesses while it is in progress. Under very
1328 rare circumstances, due to this erratum, write data can be lost when
1329 PL310 treats a cacheable write transaction during a Clean &
1330 Invalidate by Way operation.
1332 config ARM_ERRATA_743622
1333 bool "ARM errata: Faulty hazard checking in the Store Buffer may lead to data corruption"
1335 depends on !ARCH_MULTIPLATFORM
1337 This option enables the workaround for the 743622 Cortex-A9
1338 (r2p*) erratum. Under very rare conditions, a faulty
1339 optimisation in the Cortex-A9 Store Buffer may lead to data
1340 corruption. This workaround sets a specific bit in the diagnostic
1341 register of the Cortex-A9 which disables the Store Buffer
1342 optimisation, preventing the defect from occurring. This has no
1343 visible impact on the overall performance or power consumption of the
1346 config ARM_ERRATA_751472
1347 bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation"
1349 depends on !ARCH_MULTIPLATFORM
1351 This option enables the workaround for the 751472 Cortex-A9 (prior
1352 to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the
1353 completion of a following broadcasted operation if the second
1354 operation is received by a CPU before the ICIALLUIS has completed,
1355 potentially leading to corrupted entries in the cache or TLB.
1357 config PL310_ERRATA_753970
1358 bool "PL310 errata: cache sync operation may be faulty"
1359 depends on CACHE_PL310
1361 This option enables the workaround for the 753970 PL310 (r3p0) erratum.
1363 Under some condition the effect of cache sync operation on
1364 the store buffer still remains when the operation completes.
1365 This means that the store buffer is always asked to drain and
1366 this prevents it from merging any further writes. The workaround
1367 is to replace the normal offset of cache sync operation (0x730)
1368 by another offset targeting an unmapped PL310 register 0x740.
1369 This has the same effect as the cache sync operation: store buffer
1370 drain and waiting for all buffers empty.
1372 config ARM_ERRATA_754322
1373 bool "ARM errata: possible faulty MMU translations following an ASID switch"
1376 This option enables the workaround for the 754322 Cortex-A9 (r2p*,
1377 r3p*) erratum. A speculative memory access may cause a page table walk
1378 which starts prior to an ASID switch but completes afterwards. This
1379 can populate the micro-TLB with a stale entry which may be hit with
1380 the new ASID. This workaround places two dsb instructions in the mm
1381 switching code so that no page table walks can cross the ASID switch.
1383 config ARM_ERRATA_754327
1384 bool "ARM errata: no automatic Store Buffer drain"
1385 depends on CPU_V7 && SMP
1387 This option enables the workaround for the 754327 Cortex-A9 (prior to
1388 r2p0) erratum. The Store Buffer does not have any automatic draining
1389 mechanism and therefore a livelock may occur if an external agent
1390 continuously polls a memory location waiting to observe an update.
1391 This workaround defines cpu_relax() as smp_mb(), preventing correctly
1392 written polling loops from denying visibility of updates to memory.
1394 config ARM_ERRATA_364296
1395 bool "ARM errata: Possible cache data corruption with hit-under-miss enabled"
1396 depends on CPU_V6 && !SMP
1398 This options enables the workaround for the 364296 ARM1136
1399 r0p2 erratum (possible cache data corruption with
1400 hit-under-miss enabled). It sets the undocumented bit 31 in
1401 the auxiliary control register and the FI bit in the control
1402 register, thus disabling hit-under-miss without putting the
1403 processor into full low interrupt latency mode. ARM11MPCore
1406 config ARM_ERRATA_764369
1407 bool "ARM errata: Data cache line maintenance operation by MVA may not succeed"
1408 depends on CPU_V7 && SMP
1410 This option enables the workaround for erratum 764369
1411 affecting Cortex-A9 MPCore with two or more processors (all
1412 current revisions). Under certain timing circumstances, a data
1413 cache line maintenance operation by MVA targeting an Inner
1414 Shareable memory region may fail to proceed up to either the
1415 Point of Coherency or to the Point of Unification of the
1416 system. This workaround adds a DSB instruction before the
1417 relevant cache maintenance functions and sets a specific bit
1418 in the diagnostic control register of the SCU.
1420 config PL310_ERRATA_769419
1421 bool "PL310 errata: no automatic Store Buffer drain"
1422 depends on CACHE_L2X0
1424 On revisions of the PL310 prior to r3p2, the Store Buffer does
1425 not automatically drain. This can cause normal, non-cacheable
1426 writes to be retained when the memory system is idle, leading
1427 to suboptimal I/O performance for drivers using coherent DMA.
1428 This option adds a write barrier to the cpu_idle loop so that,
1429 on systems with an outer cache, the store buffer is drained
1432 config ARM_ERRATA_775420
1433 bool "ARM errata: A data cache maintenance operation which aborts, might lead to deadlock"
1436 This option enables the workaround for the 775420 Cortex-A9 (r2p2,
1437 r2p6,r2p8,r2p10,r3p0) erratum. In case a date cache maintenance
1438 operation aborts with MMU exception, it might cause the processor
1439 to deadlock. This workaround puts DSB before executing ISB if
1440 an abort may occur on cache maintenance.
1442 config ARM_ERRATA_798181
1443 bool "ARM errata: TLBI/DSB failure on Cortex-A15"
1444 depends on CPU_V7 && SMP
1446 On Cortex-A15 (r0p0..r3p2) the TLBI*IS/DSB operations are not
1447 adequately shooting down all use of the old entries. This
1448 option enables the Linux kernel workaround for this erratum
1449 which sends an IPI to the CPUs that are running the same ASID
1450 as the one being invalidated.
1454 source "arch/arm/common/Kconfig"
1464 Find out whether you have ISA slots on your motherboard. ISA is the
1465 name of a bus system, i.e. the way the CPU talks to the other stuff
1466 inside your box. Other bus systems are PCI, EISA, MicroChannel
1467 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1468 newer boards don't support it. If you have ISA, say Y, otherwise N.
1470 # Select ISA DMA controller support
1475 # Select ISA DMA interface
1480 bool "PCI support" if MIGHT_HAVE_PCI
1482 Find out whether you have a PCI motherboard. PCI is the name of a
1483 bus system, i.e. the way the CPU talks to the other stuff inside
1484 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1485 VESA. If you have PCI, say Y, otherwise N.
1491 config PCI_NANOENGINE
1492 bool "BSE nanoEngine PCI support"
1493 depends on SA1100_NANOENGINE
1495 Enable PCI on the BSE nanoEngine board.
1500 # Select the host bridge type
1501 config PCI_HOST_VIA82C505
1503 depends on PCI && ARCH_SHARK
1506 config PCI_HOST_ITE8152
1508 depends on PCI && MACH_ARMCORE
1512 source "drivers/pci/Kconfig"
1514 source "drivers/pcmcia/Kconfig"
1518 menu "Kernel Features"
1523 This option should be selected by machines which have an SMP-
1526 The only effect of this option is to make the SMP-related
1527 options available to the user for configuration.
1530 bool "Symmetric Multi-Processing"
1531 depends on CPU_V6K || CPU_V7
1532 depends on GENERIC_CLOCKEVENTS
1535 select HAVE_ARM_SCU if !ARCH_MSM_SCORPIONMP
1536 select USE_GENERIC_SMP_HELPERS
1538 This enables support for systems with more than one CPU. If you have
1539 a system with only one CPU, like most personal computers, say N. If
1540 you have a system with more than one CPU, say Y.
1542 If you say N here, the kernel will run on single and multiprocessor
1543 machines, but will use only one CPU of a multiprocessor machine. If
1544 you say Y here, the kernel will run on many, but not all, single
1545 processor machines. On a single processor machine, the kernel will
1546 run faster if you say N here.
1548 See also <file:Documentation/x86/i386/IO-APIC.txt>,
1549 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
1550 <http://tldp.org/HOWTO/SMP-HOWTO.html>.
1552 If you don't know what to do here, say N.
1555 bool "Allow booting SMP kernel on uniprocessor systems (EXPERIMENTAL)"
1556 depends on SMP && !XIP_KERNEL
1559 SMP kernels contain instructions which fail on non-SMP processors.
1560 Enabling this option allows the kernel to modify itself to make
1561 these instructions safe. Disabling it allows about 1K of space
1564 If you don't know what to do here, say Y.
1566 config ARM_CPU_TOPOLOGY
1567 bool "Support cpu topology definition"
1568 depends on SMP && CPU_V7
1571 Support ARM cpu topology definition. The MPIDR register defines
1572 affinity between processors which is then used to describe the cpu
1573 topology of an ARM System.
1576 bool "Multi-core scheduler support"
1577 depends on ARM_CPU_TOPOLOGY
1579 Multi-core scheduler support improves the CPU scheduler's decision
1580 making when dealing with multi-core CPU chips at a cost of slightly
1581 increased overhead in some places. If unsure say N here.
1584 bool "SMT scheduler support"
1585 depends on ARM_CPU_TOPOLOGY
1587 Improves the CPU scheduler's decision making when dealing with
1588 MultiThreading at a cost of slightly increased overhead in some
1589 places. If unsure say N here.
1594 This option enables support for the ARM system coherency unit
1596 config HAVE_ARM_ARCH_TIMER
1597 bool "Architected timer support"
1599 select ARM_ARCH_TIMER
1601 This option enables support for the ARM architected timer
1607 This options enables support for the ARM timer and watchdog unit
1610 prompt "Memory split"
1613 Select the desired split between kernel and user memory.
1615 If you are not absolutely sure what you are doing, leave this
1619 bool "3G/1G user/kernel split"
1621 bool "2G/2G user/kernel split"
1623 bool "1G/3G user/kernel split"
1628 default 0x40000000 if VMSPLIT_1G
1629 default 0x80000000 if VMSPLIT_2G
1633 int "Maximum number of CPUs (2-32)"
1639 bool "Support for hot-pluggable CPUs"
1640 depends on SMP && HOTPLUG
1642 Say Y here to experiment with turning CPUs off and on. CPUs
1643 can be controlled through /sys/devices/system/cpu.
1646 bool "Support for the ARM Power State Coordination Interface (PSCI)"
1649 Say Y here if you want Linux to communicate with system firmware
1650 implementing the PSCI specification for CPU-centric power
1651 management operations described in ARM document number ARM DEN
1652 0022A ("Power State Coordination Interface System Software on
1656 bool "Use local timer interrupts"
1659 select HAVE_ARM_TWD if (!ARCH_MSM_SCORPIONMP && !EXYNOS4_MCT)
1661 Enable support for local timers on SMP platforms, rather then the
1662 legacy IPI broadcast method. Local timers allows the system
1663 accounting to be spread across the timer interval, preventing a
1664 "thundering herd" at every timer tick.
1666 # The GPIO number here must be sorted by descending number. In case of
1667 # a multiplatform kernel, we just want the highest value required by the
1668 # selected platforms.
1671 default 1024 if ARCH_SHMOBILE || ARCH_TEGRA
1672 default 512 if SOC_OMAP5
1673 default 355 if ARCH_U8500
1674 default 288 if ARCH_VT8500 || ARCH_SUNXI
1675 default 264 if MACH_H4700
1678 Maximum number of GPIOs in the system.
1680 If unsure, leave the default value.
1682 source kernel/Kconfig.preempt
1686 default 200 if ARCH_EBSA110 || ARCH_S3C24XX || ARCH_S5P64X0 || \
1687 ARCH_S5PV210 || ARCH_EXYNOS4
1688 default AT91_TIMER_HZ if ARCH_AT91
1689 default SHMOBILE_TIMER_HZ if ARCH_SHMOBILE
1693 def_bool HIGH_RES_TIMERS
1695 config THUMB2_KERNEL
1696 bool "Compile the kernel in Thumb-2 mode"
1697 depends on CPU_V7 && !CPU_V6 && !CPU_V6K
1699 select ARM_ASM_UNIFIED
1702 By enabling this option, the kernel will be compiled in
1703 Thumb-2 mode. A compiler/assembler that understand the unified
1704 ARM-Thumb syntax is needed.
1708 config THUMB2_AVOID_R_ARM_THM_JUMP11
1709 bool "Work around buggy Thumb-2 short branch relocations in gas"
1710 depends on THUMB2_KERNEL && MODULES
1713 Various binutils versions can resolve Thumb-2 branches to
1714 locally-defined, preemptible global symbols as short-range "b.n"
1715 branch instructions.
1717 This is a problem, because there's no guarantee the final
1718 destination of the symbol, or any candidate locations for a
1719 trampoline, are within range of the branch. For this reason, the
1720 kernel does not support fixing up the R_ARM_THM_JUMP11 (102)
1721 relocation in modules at all, and it makes little sense to add
1724 The symptom is that the kernel fails with an "unsupported
1725 relocation" error when loading some modules.
1727 Until fixed tools are available, passing
1728 -fno-optimize-sibling-calls to gcc should prevent gcc generating
1729 code which hits this problem, at the cost of a bit of extra runtime
1730 stack usage in some cases.
1732 The problem is described in more detail at:
1733 https://bugs.launchpad.net/binutils-linaro/+bug/725126
1735 Only Thumb-2 kernels are affected.
1737 Unless you are sure your tools don't have this problem, say Y.
1739 config ARM_ASM_UNIFIED
1743 bool "Use the ARM EABI to compile the kernel"
1745 This option allows for the kernel to be compiled using the latest
1746 ARM ABI (aka EABI). This is only useful if you are using a user
1747 space environment that is also compiled with EABI.
1749 Since there are major incompatibilities between the legacy ABI and
1750 EABI, especially with regard to structure member alignment, this
1751 option also changes the kernel syscall calling convention to
1752 disambiguate both ABIs and allow for backward compatibility support
1753 (selected with CONFIG_OABI_COMPAT).
1755 To use this you need GCC version 4.0.0 or later.
1758 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1759 depends on AEABI && !THUMB2_KERNEL
1762 This option preserves the old syscall interface along with the
1763 new (ARM EABI) one. It also provides a compatibility layer to
1764 intercept syscalls that have structure arguments which layout
1765 in memory differs between the legacy ABI and the new ARM EABI
1766 (only for non "thumb" binaries). This option adds a tiny
1767 overhead to all syscalls and produces a slightly larger kernel.
1768 If you know you'll be using only pure EABI user space then you
1769 can say N here. If this option is not selected and you attempt
1770 to execute a legacy ABI binary then the result will be
1771 UNPREDICTABLE (in fact it can be predicted that it won't work
1772 at all). If in doubt say Y.
1774 config ARCH_HAS_HOLES_MEMORYMODEL
1777 config ARCH_SPARSEMEM_ENABLE
1780 config ARCH_SPARSEMEM_DEFAULT
1781 def_bool ARCH_SPARSEMEM_ENABLE
1783 config ARCH_SELECT_MEMORY_MODEL
1784 def_bool ARCH_SPARSEMEM_ENABLE
1786 config HAVE_ARCH_PFN_VALID
1787 def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM
1790 bool "High Memory Support"
1793 The address space of ARM processors is only 4 Gigabytes large
1794 and it has to accommodate user address space, kernel address
1795 space as well as some memory mapped IO. That means that, if you
1796 have a large amount of physical memory and/or IO, not all of the
1797 memory can be "permanently mapped" by the kernel. The physical
1798 memory that is not permanently mapped is called "high memory".
1800 Depending on the selected kernel/user memory split, minimum
1801 vmalloc space and actual amount of RAM, you may not need this
1802 option which should result in a slightly faster kernel.
1807 bool "Allocate 2nd-level pagetables from highmem"
1810 config HW_PERF_EVENTS
1811 bool "Enable hardware performance counter support for perf events"
1812 depends on PERF_EVENTS
1815 Enable hardware performance counter support for perf events. If
1816 disabled, perf events will use software events only.
1820 config FORCE_MAX_ZONEORDER
1821 int "Maximum zone order" if ARCH_SHMOBILE
1822 range 11 64 if ARCH_SHMOBILE
1823 default "12" if SOC_AM33XX
1824 default "9" if SA1111
1827 The kernel memory allocator divides physically contiguous memory
1828 blocks into "zones", where each zone is a power of two number of
1829 pages. This option selects the largest power of two that the kernel
1830 keeps in the memory allocator. If you need to allocate very large
1831 blocks of physically contiguous memory, then you may need to
1832 increase this value.
1834 This config option is actually maximum order plus one. For example,
1835 a value of 11 means that the largest free memory block is 2^10 pages.
1837 config ALIGNMENT_TRAP
1839 depends on CPU_CP15_MMU
1840 default y if !ARCH_EBSA110
1841 select HAVE_PROC_CPU if PROC_FS
1843 ARM processors cannot fetch/store information which is not
1844 naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1845 address divisible by 4. On 32-bit ARM processors, these non-aligned
1846 fetch/store instructions will be emulated in software if you say
1847 here, which has a severe performance impact. This is necessary for
1848 correct operation of some network protocols. With an IP-only
1849 configuration it is safe to say N, otherwise say Y.
1851 config UACCESS_WITH_MEMCPY
1852 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user()"
1854 default y if CPU_FEROCEON
1856 Implement faster copy_to_user and clear_user methods for CPU
1857 cores where a 8-word STM instruction give significantly higher
1858 memory write throughput than a sequence of individual 32bit stores.
1860 A possible side effect is a slight increase in scheduling latency
1861 between threads sharing the same address space if they invoke
1862 such copy operations with large buffers.
1864 However, if the CPU data cache is using a write-allocate mode,
1865 this option is unlikely to provide any performance gain.
1869 prompt "Enable seccomp to safely compute untrusted bytecode"
1871 This kernel feature is useful for number crunching applications
1872 that may need to compute untrusted bytecode during their
1873 execution. By using pipes or other transports made available to
1874 the process as file descriptors supporting the read/write
1875 syscalls, it's possible to isolate those applications in
1876 their own address space using seccomp. Once seccomp is
1877 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1878 and the task is only allowed to execute a few safe syscalls
1879 defined by each seccomp mode.
1881 config CC_STACKPROTECTOR
1882 bool "Enable -fstack-protector buffer overflow detection (EXPERIMENTAL)"
1884 This option turns on the -fstack-protector GCC feature. This
1885 feature puts, at the beginning of functions, a canary value on
1886 the stack just before the return address, and validates
1887 the value just before actually returning. Stack based buffer
1888 overflows (that need to overwrite this return address) now also
1889 overwrite the canary, which gets detected and the attack is then
1890 neutralized via a kernel panic.
1891 This feature requires gcc version 4.2 or above.
1898 bool "Xen guest support on ARM (EXPERIMENTAL)"
1899 depends on ARM && AEABI && OF
1900 depends on CPU_V7 && !CPU_V6
1901 depends on !GENERIC_ATOMIC64
1903 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
1910 bool "Flattened Device Tree support"
1913 select OF_EARLY_FLATTREE
1915 Include support for flattened device tree machine descriptions.
1918 bool "Support for the traditional ATAGS boot data passing" if USE_OF
1921 This is the traditional way of passing data to the kernel at boot
1922 time. If you are solely relying on the flattened device tree (or
1923 the ARM_ATAG_DTB_COMPAT option) then you may unselect this option
1924 to remove ATAGS support from your kernel binary. If unsure,
1927 config DEPRECATED_PARAM_STRUCT
1928 bool "Provide old way to pass kernel parameters"
1931 This was deprecated in 2001 and announced to live on for 5 years.
1932 Some old boot loaders still use this way.
1934 # Compressed boot loader in ROM. Yes, we really want to ask about
1935 # TEXT and BSS so we preserve their values in the config files.
1936 config ZBOOT_ROM_TEXT
1937 hex "Compressed ROM boot loader base address"
1940 The physical address at which the ROM-able zImage is to be
1941 placed in the target. Platforms which normally make use of
1942 ROM-able zImage formats normally set this to a suitable
1943 value in their defconfig file.
1945 If ZBOOT_ROM is not enabled, this has no effect.
1947 config ZBOOT_ROM_BSS
1948 hex "Compressed ROM boot loader BSS address"
1951 The base address of an area of read/write memory in the target
1952 for the ROM-able zImage which must be available while the
1953 decompressor is running. It must be large enough to hold the
1954 entire decompressed kernel plus an additional 128 KiB.
1955 Platforms which normally make use of ROM-able zImage formats
1956 normally set this to a suitable value in their defconfig file.
1958 If ZBOOT_ROM is not enabled, this has no effect.
1961 bool "Compressed boot loader in ROM/flash"
1962 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1964 Say Y here if you intend to execute your compressed kernel image
1965 (zImage) directly from ROM or flash. If unsure, say N.
1968 prompt "Include SD/MMC loader in zImage (EXPERIMENTAL)"
1969 depends on ZBOOT_ROM && ARCH_SH7372
1970 default ZBOOT_ROM_NONE
1972 Include experimental SD/MMC loading code in the ROM-able zImage.
1973 With this enabled it is possible to write the ROM-able zImage
1974 kernel image to an MMC or SD card and boot the kernel straight
1975 from the reset vector. At reset the processor Mask ROM will load
1976 the first part of the ROM-able zImage which in turn loads the
1977 rest the kernel image to RAM.
1979 config ZBOOT_ROM_NONE
1980 bool "No SD/MMC loader in zImage (EXPERIMENTAL)"
1982 Do not load image from SD or MMC
1984 config ZBOOT_ROM_MMCIF
1985 bool "Include MMCIF loader in zImage (EXPERIMENTAL)"
1987 Load image from MMCIF hardware block.
1989 config ZBOOT_ROM_SH_MOBILE_SDHI
1990 bool "Include SuperH Mobile SDHI loader in zImage (EXPERIMENTAL)"
1992 Load image from SDHI hardware block
1996 config ARM_APPENDED_DTB
1997 bool "Use appended device tree blob to zImage (EXPERIMENTAL)"
1998 depends on OF && !ZBOOT_ROM
2000 With this option, the boot code will look for a device tree binary
2001 (DTB) appended to zImage
2002 (e.g. cat zImage <filename>.dtb > zImage_w_dtb).
2004 This is meant as a backward compatibility convenience for those
2005 systems with a bootloader that can't be upgraded to accommodate
2006 the documented boot protocol using a device tree.
2008 Beware that there is very little in terms of protection against
2009 this option being confused by leftover garbage in memory that might
2010 look like a DTB header after a reboot if no actual DTB is appended
2011 to zImage. Do not leave this option active in a production kernel
2012 if you don't intend to always append a DTB. Proper passing of the
2013 location into r2 of a bootloader provided DTB is always preferable
2016 config ARM_ATAG_DTB_COMPAT
2017 bool "Supplement the appended DTB with traditional ATAG information"
2018 depends on ARM_APPENDED_DTB
2020 Some old bootloaders can't be updated to a DTB capable one, yet
2021 they provide ATAGs with memory configuration, the ramdisk address,
2022 the kernel cmdline string, etc. Such information is dynamically
2023 provided by the bootloader and can't always be stored in a static
2024 DTB. To allow a device tree enabled kernel to be used with such
2025 bootloaders, this option allows zImage to extract the information
2026 from the ATAG list and store it at run time into the appended DTB.
2029 prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT
2030 default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
2032 config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
2033 bool "Use bootloader kernel arguments if available"
2035 Uses the command-line options passed by the boot loader instead of
2036 the device tree bootargs property. If the boot loader doesn't provide
2037 any, the device tree bootargs property will be used.
2039 config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND
2040 bool "Extend with bootloader kernel arguments"
2042 The command-line arguments provided by the boot loader will be
2043 appended to the the device tree bootargs property.
2048 string "Default kernel command string"
2051 On some architectures (EBSA110 and CATS), there is currently no way
2052 for the boot loader to pass arguments to the kernel. For these
2053 architectures, you should supply some command-line options at build
2054 time by entering them here. As a minimum, you should specify the
2055 memory size and the root device (e.g., mem=64M root=/dev/nfs).
2058 prompt "Kernel command line type" if CMDLINE != ""
2059 default CMDLINE_FROM_BOOTLOADER
2062 config CMDLINE_FROM_BOOTLOADER
2063 bool "Use bootloader kernel arguments if available"
2065 Uses the command-line options passed by the boot loader. If
2066 the boot loader doesn't provide any, the default kernel command
2067 string provided in CMDLINE will be used.
2069 config CMDLINE_EXTEND
2070 bool "Extend bootloader kernel arguments"
2072 The command-line arguments provided by the boot loader will be
2073 appended to the default kernel command string.
2075 config CMDLINE_FORCE
2076 bool "Always use the default kernel command string"
2078 Always use the default kernel command string, even if the boot
2079 loader passes other arguments to the kernel.
2080 This is useful if you cannot or don't want to change the
2081 command-line options your boot loader passes to the kernel.
2085 bool "Kernel Execute-In-Place from ROM"
2086 depends on !ZBOOT_ROM && !ARM_LPAE && !ARCH_MULTIPLATFORM
2088 Execute-In-Place allows the kernel to run from non-volatile storage
2089 directly addressable by the CPU, such as NOR flash. This saves RAM
2090 space since the text section of the kernel is not loaded from flash
2091 to RAM. Read-write sections, such as the data section and stack,
2092 are still copied to RAM. The XIP kernel is not compressed since
2093 it has to run directly from flash, so it will take more space to
2094 store it. The flash address used to link the kernel object files,
2095 and for storing it, is configuration dependent. Therefore, if you
2096 say Y here, you must know the proper physical address where to
2097 store the kernel image depending on your own flash memory usage.
2099 Also note that the make target becomes "make xipImage" rather than
2100 "make zImage" or "make Image". The final kernel binary to put in
2101 ROM memory will be arch/arm/boot/xipImage.
2105 config XIP_PHYS_ADDR
2106 hex "XIP Kernel Physical Location"
2107 depends on XIP_KERNEL
2108 default "0x00080000"
2110 This is the physical address in your flash memory the kernel will
2111 be linked for and stored to. This address is dependent on your
2115 bool "Kexec system call (EXPERIMENTAL)"
2116 depends on (!SMP || HOTPLUG_CPU)
2118 kexec is a system call that implements the ability to shutdown your
2119 current kernel, and to start another kernel. It is like a reboot
2120 but it is independent of the system firmware. And like a reboot
2121 you can start any kernel with it, not just Linux.
2123 It is an ongoing process to be certain the hardware in a machine
2124 is properly shutdown, so do not be surprised if this code does not
2125 initially work for you. It may help to enable device hotplugging
2129 bool "Export atags in procfs"
2130 depends on ATAGS && KEXEC
2133 Should the atags used to boot the kernel be exported in an "atags"
2134 file in procfs. Useful with kexec.
2137 bool "Build kdump crash kernel (EXPERIMENTAL)"
2139 Generate crash dump after being started by kexec. This should
2140 be normally only set in special crash dump kernels which are
2141 loaded in the main kernel with kexec-tools into a specially
2142 reserved region and then later executed after a crash by
2143 kdump/kexec. The crash dump kernel must be compiled to a
2144 memory address not used by the main kernel
2146 For more details see Documentation/kdump/kdump.txt
2148 config AUTO_ZRELADDR
2149 bool "Auto calculation of the decompressed kernel image address"
2150 depends on !ZBOOT_ROM && !ARCH_U300
2152 ZRELADDR is the physical address where the decompressed kernel
2153 image will be placed. If AUTO_ZRELADDR is selected, the address
2154 will be determined at run-time by masking the current IP with
2155 0xf8000000. This assumes the zImage being placed in the first 128MB
2156 from start of memory.
2160 menu "CPU Power Management"
2164 source "drivers/cpufreq/Kconfig"
2167 tristate "CPUfreq driver for i.MX CPUs"
2168 depends on ARCH_MXC && CPU_FREQ
2169 select CPU_FREQ_TABLE
2171 This enables the CPUfreq driver for i.MX CPUs.
2173 config CPU_FREQ_SA1100
2176 config CPU_FREQ_SA1110
2179 config CPU_FREQ_INTEGRATOR
2180 tristate "CPUfreq driver for ARM Integrator CPUs"
2181 depends on ARCH_INTEGRATOR && CPU_FREQ
2184 This enables the CPUfreq driver for ARM Integrator CPUs.
2186 For details, take a look at <file:Documentation/cpu-freq>.
2192 depends on CPU_FREQ && ARCH_PXA && PXA25x
2194 select CPU_FREQ_DEFAULT_GOV_USERSPACE
2195 select CPU_FREQ_TABLE
2200 Internal configuration node for common cpufreq on Samsung SoC
2202 config CPU_FREQ_S3C24XX
2203 bool "CPUfreq driver for Samsung S3C24XX series CPUs (EXPERIMENTAL)"
2204 depends on ARCH_S3C24XX && CPU_FREQ
2207 This enables the CPUfreq driver for the Samsung S3C24XX family
2210 For details, take a look at <file:Documentation/cpu-freq>.
2214 config CPU_FREQ_S3C24XX_PLL
2215 bool "Support CPUfreq changing of PLL frequency (EXPERIMENTAL)"
2216 depends on CPU_FREQ_S3C24XX
2218 Compile in support for changing the PLL frequency from the
2219 S3C24XX series CPUfreq driver. The PLL takes time to settle
2220 after a frequency change, so by default it is not enabled.
2222 This also means that the PLL tables for the selected CPU(s) will
2223 be built which may increase the size of the kernel image.
2225 config CPU_FREQ_S3C24XX_DEBUG
2226 bool "Debug CPUfreq Samsung driver core"
2227 depends on CPU_FREQ_S3C24XX
2229 Enable s3c_freq_dbg for the Samsung S3C CPUfreq core
2231 config CPU_FREQ_S3C24XX_IODEBUG
2232 bool "Debug CPUfreq Samsung driver IO timing"
2233 depends on CPU_FREQ_S3C24XX
2235 Enable s3c_freq_iodbg for the Samsung S3C CPUfreq core
2237 config CPU_FREQ_S3C24XX_DEBUGFS
2238 bool "Export debugfs for CPUFreq"
2239 depends on CPU_FREQ_S3C24XX && DEBUG_FS
2241 Export status information via debugfs.
2245 source "drivers/cpuidle/Kconfig"
2249 menu "Floating point emulation"
2251 comment "At least one emulation must be selected"
2254 bool "NWFPE math emulation"
2255 depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL
2257 Say Y to include the NWFPE floating point emulator in the kernel.
2258 This is necessary to run most binaries. Linux does not currently
2259 support floating point hardware so you need to say Y here even if
2260 your machine has an FPA or floating point co-processor podule.
2262 You may say N here if you are going to load the Acorn FPEmulator
2263 early in the bootup.
2266 bool "Support extended precision"
2267 depends on FPE_NWFPE
2269 Say Y to include 80-bit support in the kernel floating-point
2270 emulator. Otherwise, only 32 and 64-bit support is compiled in.
2271 Note that gcc does not generate 80-bit operations by default,
2272 so in most cases this option only enlarges the size of the
2273 floating point emulator without any good reason.
2275 You almost surely want to say N here.
2278 bool "FastFPE math emulation (EXPERIMENTAL)"
2279 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3
2281 Say Y here to include the FAST floating point emulator in the kernel.
2282 This is an experimental much faster emulator which now also has full
2283 precision for the mantissa. It does not support any exceptions.
2284 It is very simple, and approximately 3-6 times faster than NWFPE.
2286 It should be sufficient for most programs. It may be not suitable
2287 for scientific calculations, but you have to check this for yourself.
2288 If you do not feel you need a faster FP emulation you should better
2292 bool "VFP-format floating point maths"
2293 depends on CPU_V6 || CPU_V6K || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
2295 Say Y to include VFP support code in the kernel. This is needed
2296 if your hardware includes a VFP unit.
2298 Please see <file:Documentation/arm/VFP/release-notes.txt> for
2299 release notes and additional status information.
2301 Say N if your target does not have VFP hardware.
2309 bool "Advanced SIMD (NEON) Extension support"
2310 depends on VFPv3 && CPU_V7
2312 Say Y to include support code for NEON, the ARMv7 Advanced SIMD
2317 menu "Userspace binary formats"
2319 source "fs/Kconfig.binfmt"
2322 tristate "RISC OS personality"
2325 Say Y here to include the kernel code necessary if you want to run
2326 Acorn RISC OS/Arthur binaries under Linux. This code is still very
2327 experimental; if this sounds frightening, say N and sleep in peace.
2328 You can also say M here to compile this support as a module (which
2329 will be called arthur).
2333 menu "Power management options"
2335 source "kernel/power/Kconfig"
2337 config ARCH_SUSPEND_POSSIBLE
2338 depends on !ARCH_S5PC100
2339 depends on CPU_ARM920T || CPU_ARM926T || CPU_SA1100 || \
2340 CPU_V6 || CPU_V6K || CPU_V7 || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK
2343 config ARM_CPU_SUSPEND
2348 source "net/Kconfig"
2350 source "drivers/Kconfig"
2354 source "arch/arm/Kconfig.debug"
2356 source "security/Kconfig"
2358 source "crypto/Kconfig"
2360 source "lib/Kconfig"
2362 source "arch/arm/kvm/Kconfig"