2 # For a description of the syntax of this configuration file,
3 # see Documentation/kbuild/kconfig-language.txt.
6 mainmenu "Linux Kernel Configuration"
14 select SYS_SUPPORTS_APM_EMULATION
17 select HAVE_KPROBES if (!XIP_KERNEL)
18 select HAVE_KRETPROBES if (HAVE_KPROBES)
19 select HAVE_FUNCTION_TRACER if (!XIP_KERNEL)
20 select HAVE_GENERIC_DMA_COHERENT
22 The ARM series is a line of low-power-consumption RISC chip designs
23 licensed by ARM Ltd and targeted at embedded applications and
24 handhelds such as the Compaq IPAQ. ARM-based PCs are no longer
25 manufactured, but legacy ARM-based PC hardware remains popular in
26 Europe. There is an ARM Linux project with a web page at
27 <http://www.arm.linux.org.uk/>.
32 config SYS_SUPPORTS_APM_EMULATION
41 config GENERIC_CLOCKEVENTS
44 config GENERIC_CLOCKEVENTS_BROADCAST
46 depends on GENERIC_CLOCKEVENTS
47 default y if SMP && !LOCAL_TIMERS
51 select GENERIC_ALLOCATOR
59 The Extended Industry Standard Architecture (EISA) bus was
60 developed as an open alternative to the IBM MicroChannel bus.
62 The EISA bus provided some of the features of the IBM MicroChannel
63 bus while maintaining backward compatibility with cards made for
64 the older ISA bus. The EISA bus saw limited use between 1988 and
65 1995 when it was made obsolete by the PCI bus.
67 Say Y here if you are building a kernel for an EISA-based machine.
77 MicroChannel Architecture is found in some IBM PS/2 machines and
78 laptops. It is a bus system similar to PCI or ISA. See
79 <file:Documentation/mca.txt> (and especially the web page given
80 there) before attempting to build an MCA bus kernel.
82 config GENERIC_HARDIRQS
86 config STACKTRACE_SUPPORT
90 config HAVE_LATENCYTOP_SUPPORT
95 config LOCKDEP_SUPPORT
99 config TRACE_IRQFLAGS_SUPPORT
103 config HARDIRQS_SW_RESEND
107 config GENERIC_IRQ_PROBE
111 config GENERIC_LOCKBREAK
114 depends on SMP && PREEMPT
116 config RWSEM_GENERIC_SPINLOCK
120 config RWSEM_XCHGADD_ALGORITHM
123 config ARCH_HAS_ILOG2_U32
126 config ARCH_HAS_ILOG2_U64
129 config ARCH_HAS_CPUFREQ
132 Internal node to signify that the ARCH has CPUFREQ support
133 and that the relevant menu configurations are displayed for
136 config GENERIC_HWEIGHT
140 config GENERIC_CALIBRATE_DELAY
144 config ARCH_MAY_HAVE_PC_FDC
150 config GENERIC_ISA_DMA
159 config GENERIC_HARDIRQS_NO__DO_IRQ
164 config OPROFILE_ARMV6
166 depends on CPU_V6 && !SMP
167 select OPROFILE_ARM11_CORE
169 config OPROFILE_MPCORE
171 depends on CPU_V6 && SMP
172 select OPROFILE_ARM11_CORE
174 config OPROFILE_ARM11_CORE
177 config OPROFILE_ARMV7
179 depends on CPU_V7 && !SMP
186 default 0xffff0000 if MMU || CPU_HIGH_VECTOR
187 default DRAM_BASE if REMAP_VECTORS_TO_RAM
190 The base address of exception vectors.
192 source "init/Kconfig"
194 source "kernel/Kconfig.freezer"
199 bool "MMU-based Paged Memory Management Support"
202 Select if you want MMU-based virtualised addressing space
203 support by paged memory management. If unsure, say 'Y'.
206 prompt "ARM system type"
207 default ARCH_VERSATILE
210 bool "Agilent AAEC-2000 based"
215 This enables support for systems based on the Agilent AAEC-2000
217 config ARCH_INTEGRATOR
218 bool "ARM Ltd. Integrator family"
220 select ARCH_HAS_CPUFREQ
225 Support for ARM's Integrator platform.
228 bool "ARM Ltd. RealView family"
234 select GENERIC_CLOCKEVENTS
235 select ARCH_WANT_OPTIONAL_GPIOLIB
237 This enables support for ARM Ltd RealView boards.
239 config ARCH_VERSATILE
240 bool "ARM Ltd. Versatile family"
247 select GENERIC_CLOCKEVENTS
248 select ARCH_WANT_OPTIONAL_GPIOLIB
250 This enables support for ARM Ltd Versatile board.
255 select ARCH_REQUIRE_GPIOLIB
258 This enables support for systems based on the Atmel AT91RM9200,
259 AT91SAM9 and AT91CAP9 processors.
262 bool "Cirrus Logic CLPS711x/EP721x-based"
265 Support for Cirrus Logic 711x/721x based boards.
268 bool "Cortina Systems Gemini"
271 select ARCH_REQUIRE_GPIOLIB
273 Support for the Cortina Systems Gemini family SoCs
281 This is an evaluation board for the StrongARM processor available
282 from Digital. It has limited hardware on-board, including an
283 Ethernet interface, two PCMCIA sockets, two serial ports and a
294 select ARCH_REQUIRE_GPIOLIB
295 select ARCH_HAS_HOLES_MEMORYMODEL
297 This enables support for the Cirrus EP93xx series of CPUs.
299 config ARCH_FOOTBRIDGE
304 Support for systems based on the DC21285 companion chip
305 ("FootBridge"), such as the Simtec CATS and the Rebel NetWinder.
308 bool "Freescale MXC/iMX-based"
310 select GENERIC_CLOCKEVENTS
313 select ARCH_REQUIRE_GPIOLIB
316 Support for Freescale MXC/iMX-based family of processors
319 bool "Freescale STMP3xxx"
323 select ARCH_REQUIRE_GPIOLIB
325 select GENERIC_CLOCKEVENTS
327 select USB_ARCH_HAS_EHCI
329 Support for systems based on the Freescale 3xxx CPUs.
332 bool "Hilscher NetX based"
335 select GENERIC_CLOCKEVENTS
338 This enables support for systems based on the Hilscher NetX Soc
341 bool "Hynix HMS720x-based"
345 This enables support for systems based on the Hynix HMS720x
348 bool "STMicroelectronics Nomadik"
355 select GENERIC_CLOCKEVENTS
357 select ARCH_REQUIRE_GPIOLIB
359 Support for the Nomadik platform by ST-Ericsson
367 select ARCH_SUPPORTS_MSI
370 Support for Intel's IOP13XX (XScale) family of processors.
379 select ARCH_REQUIRE_GPIOLIB
381 Support for Intel's 80219 and IOP32X (XScale) family of
391 select ARCH_REQUIRE_GPIOLIB
393 Support for Intel's IOP33X (XScale) family of processors.
401 Support for Intel's IXP23xx (XScale) family of processors.
404 bool "IXP2400/2800-based"
409 Support for Intel's IXP2400/2800 (XScale) family of processors.
417 select GENERIC_CLOCKEVENTS
418 select DMABOUNCE if PCI
420 Support for Intel's IXP4XX (XScale) family of processors.
427 Say Y here if you intend to run this kernel on a LinkUp Systems
428 L7200 Software Development Board which uses an ARM720T processor.
429 Information on this board can be obtained at:
431 <http://www.linkupsys.com/>
433 If you have any questions or comments about the Linux kernel port
434 to this board, send e-mail to <sjhill@cotw.com>.
440 select ARCH_REQUIRE_GPIOLIB
442 select GENERIC_CLOCKEVENTS
445 Support for the Marvell Dove SoC 88AP510
448 bool "Marvell Kirkwood"
452 select ARCH_REQUIRE_GPIOLIB
454 select GENERIC_CLOCKEVENTS
457 Support for the following Marvell Kirkwood series SoCs:
458 88F6180, 88F6192 and 88F6281.
461 bool "Marvell Loki (88RC8480)"
464 select GENERIC_CLOCKEVENTS
467 Support for the Marvell Loki (88RC8480) SoC.
470 bool "Marvell MV78xx0"
474 select ARCH_REQUIRE_GPIOLIB
476 select GENERIC_CLOCKEVENTS
479 Support for the following Marvell MV78xx0 series SoCs:
488 select ARCH_REQUIRE_GPIOLIB
490 select GENERIC_CLOCKEVENTS
493 Support for the following Marvell Orion 5x series SoCs:
494 Orion-1 (5181), Orion-VoIP (5181L), Orion-NAS (5182),
495 Orion-2 (5281), Orion-1-90 (6183).
498 bool "Marvell PXA168/910"
501 select ARCH_REQUIRE_GPIOLIB
505 select GENERIC_CLOCKEVENTS
509 Support for Marvell's PXA168/910 processor line.
512 bool "Micrel/Kendin KS8695"
515 select ARCH_REQUIRE_GPIOLIB
517 Support for Micrel/Kendin KS8695 "Centaur" (ARM922T) based
518 System-on-Chip devices.
521 bool "NetSilicon NS9xxx"
525 select GENERIC_CLOCKEVENTS
528 Say Y here if you intend to run this kernel on a NetSilicon NS9xxx
531 <http://www.digi.com/products/microprocessors/index.jsp>
534 bool "Nuvoton W90X900 CPU"
536 select ARCH_REQUIRE_GPIOLIB
541 select GENERIC_CLOCKEVENTS
543 Support for Nuvoton (Winbond logic dept.) ARM9 processor,
544 At present, the w90x900 has been renamed nuc900, regarding
545 the ARM series product line, you can login the following
546 link address to know more.
548 <http://www.nuvoton.com/hq/enu/ProductAndSales/ProductLines/
549 ConsumerElectronicsIC/ARMMicrocontroller/ARMMicrocontroller>
552 bool "Philips Nexperia PNX4008 Mobile"
556 This enables support for Philips PNX4008 mobile platform.
559 bool "PXA2xx/PXA3xx-based"
562 select ARCH_HAS_CPUFREQ
566 select ARCH_REQUIRE_GPIOLIB
568 select GENERIC_CLOCKEVENTS
572 Support for Intel/Marvell's PXA2xx/PXA3xx processor line.
578 select GENERIC_CLOCKEVENTS
580 Support for Qualcomm MSM7K based systems. This runs on the ARM11
581 apps processor of the MSM7K and depends on a shared memory
582 interface to the ARM9 modem processor which runs the baseband stack
583 and controls some vital subsystems (clock and power control, etc).
590 select ARCH_MAY_HAVE_PC_FDC
591 select HAVE_PATA_PLATFORM
594 select ARCH_SPARSEMEM_ENABLE
596 On the Acorn Risc-PC, Linux can support the internal IDE disk and
597 CD-ROM interface, serial and parallel port, and the floppy drive.
603 select ARCH_SPARSEMEM_ENABLE
605 select ARCH_HAS_CPUFREQ
609 select GENERIC_CLOCKEVENTS
612 select ARCH_REQUIRE_GPIOLIB
614 Support for StrongARM 11x0 based boards.
617 bool "Samsung S3C2410, S3C2412, S3C2413, S3C2440, S3C2442, S3C2443"
619 select ARCH_HAS_CPUFREQ
622 Samsung S3C2410X CPU based systems, such as the Simtec Electronics
623 BAST (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or
624 the Samsung SMDK2410 development board (and derivatives).
627 bool "Samsung S3C64XX"
630 select ARCH_HAS_CPUFREQ
632 Samsung S3C64XX series based systems
635 bool "Samsung S5PC1XX"
640 Samsung S5PC1XX series based systems
650 Support for the StrongARM based Digital DNARD machine, also known
651 as "Shark" (<http://www.shark-linux.de/shark.html>).
656 select ARCH_DISCONTIGMEM_ENABLE if !LH7A40X_CONTIGMEM
657 select ARCH_SPARSEMEM_ENABLE if !LH7A40X_CONTIGMEM
659 Say Y here for systems based on one of the Sharp LH7A40X
660 System on a Chip processors. These CPUs include an ARM922T
661 core with a wide array of integrated devices for
662 hand-held and low-power applications.
665 bool "ST-Ericsson U300 Series"
672 select GENERIC_CLOCKEVENTS
677 Support for ST-Ericsson U300 series mobile platforms.
683 select GENERIC_CLOCKEVENTS
685 select ARCH_REQUIRE_GPIOLIB
690 select GENERIC_ALLOCATOR
691 select ARCH_HAS_HOLES_MEMORYMODEL
693 Support for TI's DaVinci platform.
699 select ARCH_REQUIRE_GPIOLIB
700 select ARCH_HAS_CPUFREQ
702 select GENERIC_CLOCKEVENTS
704 Support for TI's OMAP platform (OMAP1 and OMAP2).
707 bool "Broadcom BCMRING"
713 select GENERIC_CLOCKEVENTS
714 select ARCH_WANT_OPTIONAL_GPIOLIB
716 Support for Broadcom's BCMRing platform.
719 bool "ST-Ericsson U8500 Series"
723 select GENERIC_CLOCKEVENTS
726 Support for ST-Ericsson's Ux500 architecture
730 source "arch/arm/mach-clps711x/Kconfig"
732 source "arch/arm/mach-ep93xx/Kconfig"
734 source "arch/arm/mach-footbridge/Kconfig"
736 source "arch/arm/mach-gemini/Kconfig"
738 source "arch/arm/mach-integrator/Kconfig"
740 source "arch/arm/mach-iop32x/Kconfig"
742 source "arch/arm/mach-iop33x/Kconfig"
744 source "arch/arm/mach-iop13xx/Kconfig"
746 source "arch/arm/mach-ixp4xx/Kconfig"
748 source "arch/arm/mach-ixp2000/Kconfig"
750 source "arch/arm/mach-ixp23xx/Kconfig"
752 source "arch/arm/mach-loki/Kconfig"
754 source "arch/arm/mach-mv78xx0/Kconfig"
756 source "arch/arm/mach-pxa/Kconfig"
757 source "arch/arm/plat-pxa/Kconfig"
759 source "arch/arm/mach-mmp/Kconfig"
761 source "arch/arm/mach-sa1100/Kconfig"
763 source "arch/arm/plat-omap/Kconfig"
765 source "arch/arm/mach-omap1/Kconfig"
767 source "arch/arm/mach-omap2/Kconfig"
769 source "arch/arm/mach-orion5x/Kconfig"
771 source "arch/arm/mach-kirkwood/Kconfig"
773 source "arch/arm/mach-dove/Kconfig"
775 source "arch/arm/plat-samsung/Kconfig"
776 source "arch/arm/plat-s3c24xx/Kconfig"
777 source "arch/arm/plat-s3c64xx/Kconfig"
778 source "arch/arm/plat-s3c/Kconfig"
779 source "arch/arm/plat-s5pc1xx/Kconfig"
782 source "arch/arm/mach-s3c2400/Kconfig"
783 source "arch/arm/mach-s3c2410/Kconfig"
784 source "arch/arm/mach-s3c2412/Kconfig"
785 source "arch/arm/mach-s3c2440/Kconfig"
786 source "arch/arm/mach-s3c2442/Kconfig"
787 source "arch/arm/mach-s3c2443/Kconfig"
791 source "arch/arm/mach-s3c6400/Kconfig"
792 source "arch/arm/mach-s3c6410/Kconfig"
795 source "arch/arm/plat-stmp3xxx/Kconfig"
798 source "arch/arm/mach-s5pc100/Kconfig"
801 source "arch/arm/mach-lh7a40x/Kconfig"
803 source "arch/arm/mach-h720x/Kconfig"
805 source "arch/arm/mach-versatile/Kconfig"
807 source "arch/arm/mach-aaec2000/Kconfig"
809 source "arch/arm/mach-realview/Kconfig"
811 source "arch/arm/mach-at91/Kconfig"
813 source "arch/arm/plat-mxc/Kconfig"
815 source "arch/arm/mach-nomadik/Kconfig"
816 source "arch/arm/plat-nomadik/Kconfig"
818 source "arch/arm/mach-netx/Kconfig"
820 source "arch/arm/mach-ns9xxx/Kconfig"
822 source "arch/arm/mach-davinci/Kconfig"
824 source "arch/arm/mach-ks8695/Kconfig"
826 source "arch/arm/mach-msm/Kconfig"
828 source "arch/arm/mach-u300/Kconfig"
830 source "arch/arm/mach-w90x900/Kconfig"
832 source "arch/arm/mach-bcmring/Kconfig"
834 source "arch/arm/mach-ux500/Kconfig"
836 # Definitions to make life easier
842 select GENERIC_CLOCKEVENTS
851 source arch/arm/mm/Kconfig
854 bool "Enable iWMMXt support"
855 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK
856 default y if PXA27x || PXA3xx || ARCH_MMP
858 Enable support for iWMMXt context switching at run time if
859 running on a CPU that supports it.
861 # bool 'Use XScale PMU as timer source' CONFIG_XSCALE_PMU_TIMER
864 depends on CPU_XSCALE && !XSCALE_PMU_TIMER
868 source "arch/arm/Kconfig-nommu"
871 config ARM_ERRATA_411920
872 bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
873 depends on CPU_V6 && !SMP
875 Invalidation of the Instruction Cache operation can
876 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
877 It does not affect the MPCore. This option enables the ARM Ltd.
878 recommended workaround.
880 config ARM_ERRATA_430973
881 bool "ARM errata: Stale prediction on replaced interworking branch"
884 This option enables the workaround for the 430973 Cortex-A8
885 (r1p0..r1p2) erratum. If a code sequence containing an ARM/Thumb
886 interworking branch is replaced with another code sequence at the
887 same virtual address, whether due to self-modifying code or virtual
888 to physical address re-mapping, Cortex-A8 does not recover from the
889 stale interworking branch prediction. This results in Cortex-A8
890 executing the new code sequence in the incorrect ARM or Thumb state.
891 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
892 and also flushes the branch target cache at every context switch.
893 Note that setting specific bits in the ACTLR register may not be
894 available in non-secure mode.
896 config ARM_ERRATA_458693
897 bool "ARM errata: Processor deadlock when a false hazard is created"
900 This option enables the workaround for the 458693 Cortex-A8 (r2p0)
901 erratum. For very specific sequences of memory operations, it is
902 possible for a hazard condition intended for a cache line to instead
903 be incorrectly associated with a different cache line. This false
904 hazard might then cause a processor deadlock. The workaround enables
905 the L1 caching of the NEON accesses and disables the PLD instruction
906 in the ACTLR register. Note that setting specific bits in the ACTLR
907 register may not be available in non-secure mode.
909 config ARM_ERRATA_460075
910 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
913 This option enables the workaround for the 460075 Cortex-A8 (r2p0)
914 erratum. Any asynchronous access to the L2 cache may encounter a
915 situation in which recent store transactions to the L2 cache are lost
916 and overwritten with stale memory contents from external memory. The
917 workaround disables the write-allocate mode for the L2 cache via the
918 ACTLR register. Note that setting specific bits in the ACTLR register
919 may not be available in non-secure mode.
923 source "arch/arm/common/Kconfig"
925 config FORCE_MAX_ZONEORDER
938 Find out whether you have ISA slots on your motherboard. ISA is the
939 name of a bus system, i.e. the way the CPU talks to the other stuff
940 inside your box. Other bus systems are PCI, EISA, MicroChannel
941 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
942 newer boards don't support it. If you have ISA, say Y, otherwise N.
944 # Select ISA DMA controller support
949 # Select ISA DMA interface
954 bool "PCI support" if ARCH_INTEGRATOR_AP || ARCH_VERSATILE_PB || ARCH_IXP4XX || ARCH_KS8695 || MACH_ARMCORE
956 Find out whether you have a PCI motherboard. PCI is the name of a
957 bus system, i.e. the way the CPU talks to the other stuff inside
958 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
959 VESA. If you have PCI, say Y, otherwise N.
964 # Select the host bridge type
965 config PCI_HOST_VIA82C505
967 depends on PCI && ARCH_SHARK
970 config PCI_HOST_ITE8152
972 depends on PCI && MACH_ARMCORE
976 source "drivers/pci/Kconfig"
978 source "drivers/pcmcia/Kconfig"
982 menu "Kernel Features"
984 source "kernel/time/Kconfig"
987 bool "Symmetric Multi-Processing (EXPERIMENTAL)"
988 depends on EXPERIMENTAL && (REALVIEW_EB_ARM11MP || REALVIEW_EB_A9MP ||\
989 MACH_REALVIEW_PB11MP || MACH_REALVIEW_PBX || ARCH_OMAP4 || ARCH_U8500)
990 depends on GENERIC_CLOCKEVENTS
991 select USE_GENERIC_SMP_HELPERS
992 select HAVE_ARM_SCU if (ARCH_REALVIEW || ARCH_OMAP4 || ARCH_U8500)
994 This enables support for systems with more than one CPU. If you have
995 a system with only one CPU, like most personal computers, say N. If
996 you have a system with more than one CPU, say Y.
998 If you say N here, the kernel will run on single and multiprocessor
999 machines, but will use only one CPU of a multiprocessor machine. If
1000 you say Y here, the kernel will run on many, but not all, single
1001 processor machines. On a single processor machine, the kernel will
1002 run faster if you say N here.
1004 See also <file:Documentation/i386/IO-APIC.txt>,
1005 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
1006 <http://www.linuxdoc.org/docs.html#howto>.
1008 If you don't know what to do here, say N.
1014 This option enables support for the ARM system coherency unit
1020 This options enables support for the ARM timer and watchdog unit
1023 prompt "Memory split"
1026 Select the desired split between kernel and user memory.
1028 If you are not absolutely sure what you are doing, leave this
1032 bool "3G/1G user/kernel split"
1034 bool "2G/2G user/kernel split"
1036 bool "1G/3G user/kernel split"
1041 default 0x40000000 if VMSPLIT_1G
1042 default 0x80000000 if VMSPLIT_2G
1046 int "Maximum number of CPUs (2-32)"
1052 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
1053 depends on SMP && HOTPLUG && EXPERIMENTAL
1055 Say Y here to experiment with turning CPUs off and on. CPUs
1056 can be controlled through /sys/devices/system/cpu.
1059 bool "Use local timer interrupts"
1060 depends on SMP && (REALVIEW_EB_ARM11MP || MACH_REALVIEW_PB11MP || \
1061 REALVIEW_EB_A9MP || MACH_REALVIEW_PBX || ARCH_OMAP4 || ARCH_U8500)
1063 select HAVE_ARM_TWD if (ARCH_REALVIEW || ARCH_OMAP4 || ARCH_U8500)
1065 Enable support for local timers on SMP platforms, rather then the
1066 legacy IPI broadcast method. Local timers allows the system
1067 accounting to be spread across the timer interval, preventing a
1068 "thundering herd" at every timer tick.
1070 source kernel/Kconfig.preempt
1074 default 128 if ARCH_L7200
1075 default 200 if ARCH_EBSA110 || ARCH_S3C2410
1076 default OMAP_32K_TIMER_HZ if ARCH_OMAP && OMAP_32K_TIMER
1077 default AT91_TIMER_HZ if ARCH_AT91
1080 config THUMB2_KERNEL
1081 bool "Compile the kernel in Thumb-2 mode"
1082 depends on CPU_V7 && EXPERIMENTAL
1084 select ARM_ASM_UNIFIED
1086 By enabling this option, the kernel will be compiled in
1087 Thumb-2 mode. A compiler/assembler that understand the unified
1088 ARM-Thumb syntax is needed.
1092 config ARM_ASM_UNIFIED
1096 bool "Use the ARM EABI to compile the kernel"
1098 This option allows for the kernel to be compiled using the latest
1099 ARM ABI (aka EABI). This is only useful if you are using a user
1100 space environment that is also compiled with EABI.
1102 Since there are major incompatibilities between the legacy ABI and
1103 EABI, especially with regard to structure member alignment, this
1104 option also changes the kernel syscall calling convention to
1105 disambiguate both ABIs and allow for backward compatibility support
1106 (selected with CONFIG_OABI_COMPAT).
1108 To use this you need GCC version 4.0.0 or later.
1111 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1112 depends on AEABI && EXPERIMENTAL
1115 This option preserves the old syscall interface along with the
1116 new (ARM EABI) one. It also provides a compatibility layer to
1117 intercept syscalls that have structure arguments which layout
1118 in memory differs between the legacy ABI and the new ARM EABI
1119 (only for non "thumb" binaries). This option adds a tiny
1120 overhead to all syscalls and produces a slightly larger kernel.
1121 If you know you'll be using only pure EABI user space then you
1122 can say N here. If this option is not selected and you attempt
1123 to execute a legacy ABI binary then the result will be
1124 UNPREDICTABLE (in fact it can be predicted that it won't work
1125 at all). If in doubt say Y.
1127 config ARCH_HAS_HOLES_MEMORYMODEL
1130 # Discontigmem is deprecated
1131 config ARCH_DISCONTIGMEM_ENABLE
1134 config ARCH_SPARSEMEM_ENABLE
1137 config ARCH_SPARSEMEM_DEFAULT
1138 def_bool ARCH_SPARSEMEM_ENABLE
1140 config ARCH_SELECT_MEMORY_MODEL
1141 def_bool ARCH_DISCONTIGMEM_ENABLE && ARCH_SPARSEMEM_ENABLE
1145 default "4" if ARCH_LH7A40X
1147 depends on NEED_MULTIPLE_NODES
1150 bool "High Memory Support (EXPERIMENTAL)"
1151 depends on MMU && EXPERIMENTAL
1153 The address space of ARM processors is only 4 Gigabytes large
1154 and it has to accommodate user address space, kernel address
1155 space as well as some memory mapped IO. That means that, if you
1156 have a large amount of physical memory and/or IO, not all of the
1157 memory can be "permanently mapped" by the kernel. The physical
1158 memory that is not permanently mapped is called "high memory".
1160 Depending on the selected kernel/user memory split, minimum
1161 vmalloc space and actual amount of RAM, you may not need this
1162 option which should result in a slightly faster kernel.
1167 bool "Allocate 2nd-level pagetables from highmem"
1169 depends on !OUTER_CACHE
1174 bool "Timer and CPU usage LEDs"
1175 depends on ARCH_CDB89712 || ARCH_EBSA110 || \
1176 ARCH_EBSA285 || ARCH_INTEGRATOR || \
1177 ARCH_LUBBOCK || MACH_MAINSTONE || ARCH_NETWINDER || \
1178 ARCH_OMAP || ARCH_P720T || ARCH_PXA_IDP || \
1179 ARCH_SA1100 || ARCH_SHARK || ARCH_VERSATILE || \
1180 ARCH_AT91 || ARCH_DAVINCI || \
1181 ARCH_KS8695 || MACH_RD88F5182 || ARCH_REALVIEW
1183 If you say Y here, the LEDs on your machine will be used
1184 to provide useful information about your current system status.
1186 If you are compiling a kernel for a NetWinder or EBSA-285, you will
1187 be able to select which LEDs are active using the options below. If
1188 you are compiling a kernel for the EBSA-110 or the LART however, the
1189 red LED will simply flash regularly to indicate that the system is
1190 still functional. It is safe to say Y here if you have a CATS
1191 system, but the driver will do nothing.
1194 bool "Timer LED" if (!ARCH_CDB89712 && !ARCH_OMAP) || \
1195 OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1196 || MACH_OMAP_PERSEUS2
1198 depends on !GENERIC_CLOCKEVENTS
1199 default y if ARCH_EBSA110
1201 If you say Y here, one of the system LEDs (the green one on the
1202 NetWinder, the amber one on the EBSA285, or the red one on the LART)
1203 will flash regularly to indicate that the system is still
1204 operational. This is mainly useful to kernel hackers who are
1205 debugging unstable kernels.
1207 The LART uses the same LED for both Timer LED and CPU usage LED
1208 functions. You may choose to use both, but the Timer LED function
1209 will overrule the CPU usage LED.
1212 bool "CPU usage LED" if (!ARCH_CDB89712 && !ARCH_EBSA110 && \
1214 || OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1215 || MACH_OMAP_PERSEUS2
1218 If you say Y here, the red LED will be used to give a good real
1219 time indication of CPU usage, by lighting whenever the idle task
1220 is not currently executing.
1222 The LART uses the same LED for both Timer LED and CPU usage LED
1223 functions. You may choose to use both, but the Timer LED function
1224 will overrule the CPU usage LED.
1226 config ALIGNMENT_TRAP
1228 depends on CPU_CP15_MMU
1229 default y if !ARCH_EBSA110
1231 ARM processors cannot fetch/store information which is not
1232 naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1233 address divisible by 4. On 32-bit ARM processors, these non-aligned
1234 fetch/store instructions will be emulated in software if you say
1235 here, which has a severe performance impact. This is necessary for
1236 correct operation of some network protocols. With an IP-only
1237 configuration it is safe to say N, otherwise say Y.
1239 config UACCESS_WITH_MEMCPY
1240 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user() (EXPERIMENTAL)"
1241 depends on MMU && EXPERIMENTAL
1242 default y if CPU_FEROCEON
1244 Implement faster copy_to_user and clear_user methods for CPU
1245 cores where a 8-word STM instruction give significantly higher
1246 memory write throughput than a sequence of individual 32bit stores.
1248 A possible side effect is a slight increase in scheduling latency
1249 between threads sharing the same address space if they invoke
1250 such copy operations with large buffers.
1252 However, if the CPU data cache is using a write-allocate mode,
1253 this option is unlikely to provide any performance gain.
1259 # Compressed boot loader in ROM. Yes, we really want to ask about
1260 # TEXT and BSS so we preserve their values in the config files.
1261 config ZBOOT_ROM_TEXT
1262 hex "Compressed ROM boot loader base address"
1265 The physical address at which the ROM-able zImage is to be
1266 placed in the target. Platforms which normally make use of
1267 ROM-able zImage formats normally set this to a suitable
1268 value in their defconfig file.
1270 If ZBOOT_ROM is not enabled, this has no effect.
1272 config ZBOOT_ROM_BSS
1273 hex "Compressed ROM boot loader BSS address"
1276 The base address of an area of read/write memory in the target
1277 for the ROM-able zImage which must be available while the
1278 decompressor is running. It must be large enough to hold the
1279 entire decompressed kernel plus an additional 128 KiB.
1280 Platforms which normally make use of ROM-able zImage formats
1281 normally set this to a suitable value in their defconfig file.
1283 If ZBOOT_ROM is not enabled, this has no effect.
1286 bool "Compressed boot loader in ROM/flash"
1287 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1289 Say Y here if you intend to execute your compressed kernel image
1290 (zImage) directly from ROM or flash. If unsure, say N.
1293 string "Default kernel command string"
1296 On some architectures (EBSA110 and CATS), there is currently no way
1297 for the boot loader to pass arguments to the kernel. For these
1298 architectures, you should supply some command-line options at build
1299 time by entering them here. As a minimum, you should specify the
1300 memory size and the root device (e.g., mem=64M root=/dev/nfs).
1303 bool "Kernel Execute-In-Place from ROM"
1304 depends on !ZBOOT_ROM
1306 Execute-In-Place allows the kernel to run from non-volatile storage
1307 directly addressable by the CPU, such as NOR flash. This saves RAM
1308 space since the text section of the kernel is not loaded from flash
1309 to RAM. Read-write sections, such as the data section and stack,
1310 are still copied to RAM. The XIP kernel is not compressed since
1311 it has to run directly from flash, so it will take more space to
1312 store it. The flash address used to link the kernel object files,
1313 and for storing it, is configuration dependent. Therefore, if you
1314 say Y here, you must know the proper physical address where to
1315 store the kernel image depending on your own flash memory usage.
1317 Also note that the make target becomes "make xipImage" rather than
1318 "make zImage" or "make Image". The final kernel binary to put in
1319 ROM memory will be arch/arm/boot/xipImage.
1323 config XIP_PHYS_ADDR
1324 hex "XIP Kernel Physical Location"
1325 depends on XIP_KERNEL
1326 default "0x00080000"
1328 This is the physical address in your flash memory the kernel will
1329 be linked for and stored to. This address is dependent on your
1333 bool "Kexec system call (EXPERIMENTAL)"
1334 depends on EXPERIMENTAL
1336 kexec is a system call that implements the ability to shutdown your
1337 current kernel, and to start another kernel. It is like a reboot
1338 but it is independent of the system firmware. And like a reboot
1339 you can start any kernel with it, not just Linux.
1341 It is an ongoing process to be certain the hardware in a machine
1342 is properly shutdown, so do not be surprised if this code does not
1343 initially work for you. It may help to enable device hotplugging
1347 bool "Export atags in procfs"
1351 Should the atags used to boot the kernel be exported in an "atags"
1352 file in procfs. Useful with kexec.
1356 menu "CPU Power Management"
1360 source "drivers/cpufreq/Kconfig"
1362 config CPU_FREQ_SA1100
1365 config CPU_FREQ_SA1110
1368 config CPU_FREQ_INTEGRATOR
1369 tristate "CPUfreq driver for ARM Integrator CPUs"
1370 depends on ARCH_INTEGRATOR && CPU_FREQ
1373 This enables the CPUfreq driver for ARM Integrator CPUs.
1375 For details, take a look at <file:Documentation/cpu-freq>.
1381 depends on CPU_FREQ && ARCH_PXA && PXA25x
1383 select CPU_FREQ_DEFAULT_GOV_USERSPACE
1385 config CPU_FREQ_S3C64XX
1386 bool "CPUfreq support for Samsung S3C64XX CPUs"
1387 depends on CPU_FREQ && CPU_S3C6410
1392 Internal configuration node for common cpufreq on Samsung SoC
1394 config CPU_FREQ_S3C24XX
1395 bool "CPUfreq driver for Samsung S3C24XX series CPUs"
1396 depends on ARCH_S3C2410 && CPU_FREQ && EXPERIMENTAL
1399 This enables the CPUfreq driver for the Samsung S3C24XX family
1402 For details, take a look at <file:Documentation/cpu-freq>.
1406 config CPU_FREQ_S3C24XX_PLL
1407 bool "Support CPUfreq changing of PLL frequency"
1408 depends on CPU_FREQ_S3C24XX && EXPERIMENTAL
1410 Compile in support for changing the PLL frequency from the
1411 S3C24XX series CPUfreq driver. The PLL takes time to settle
1412 after a frequency change, so by default it is not enabled.
1414 This also means that the PLL tables for the selected CPU(s) will
1415 be built which may increase the size of the kernel image.
1417 config CPU_FREQ_S3C24XX_DEBUG
1418 bool "Debug CPUfreq Samsung driver core"
1419 depends on CPU_FREQ_S3C24XX
1421 Enable s3c_freq_dbg for the Samsung S3C CPUfreq core
1423 config CPU_FREQ_S3C24XX_IODEBUG
1424 bool "Debug CPUfreq Samsung driver IO timing"
1425 depends on CPU_FREQ_S3C24XX
1427 Enable s3c_freq_iodbg for the Samsung S3C CPUfreq core
1429 config CPU_FREQ_S3C24XX_DEBUGFS
1430 bool "Export debugfs for CPUFreq"
1431 depends on CPU_FREQ_S3C24XX && DEBUG_FS
1433 Export status information via debugfs.
1437 source "drivers/cpuidle/Kconfig"
1441 menu "Floating point emulation"
1443 comment "At least one emulation must be selected"
1446 bool "NWFPE math emulation"
1447 depends on !AEABI || OABI_COMPAT
1449 Say Y to include the NWFPE floating point emulator in the kernel.
1450 This is necessary to run most binaries. Linux does not currently
1451 support floating point hardware so you need to say Y here even if
1452 your machine has an FPA or floating point co-processor podule.
1454 You may say N here if you are going to load the Acorn FPEmulator
1455 early in the bootup.
1458 bool "Support extended precision"
1459 depends on FPE_NWFPE
1461 Say Y to include 80-bit support in the kernel floating-point
1462 emulator. Otherwise, only 32 and 64-bit support is compiled in.
1463 Note that gcc does not generate 80-bit operations by default,
1464 so in most cases this option only enlarges the size of the
1465 floating point emulator without any good reason.
1467 You almost surely want to say N here.
1470 bool "FastFPE math emulation (EXPERIMENTAL)"
1471 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3 && EXPERIMENTAL
1473 Say Y here to include the FAST floating point emulator in the kernel.
1474 This is an experimental much faster emulator which now also has full
1475 precision for the mantissa. It does not support any exceptions.
1476 It is very simple, and approximately 3-6 times faster than NWFPE.
1478 It should be sufficient for most programs. It may be not suitable
1479 for scientific calculations, but you have to check this for yourself.
1480 If you do not feel you need a faster FP emulation you should better
1484 bool "VFP-format floating point maths"
1485 depends on CPU_V6 || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
1487 Say Y to include VFP support code in the kernel. This is needed
1488 if your hardware includes a VFP unit.
1490 Please see <file:Documentation/arm/VFP/release-notes.txt> for
1491 release notes and additional status information.
1493 Say N if your target does not have VFP hardware.
1501 bool "Advanced SIMD (NEON) Extension support"
1502 depends on VFPv3 && CPU_V7
1504 Say Y to include support code for NEON, the ARMv7 Advanced SIMD
1509 menu "Userspace binary formats"
1511 source "fs/Kconfig.binfmt"
1514 tristate "RISC OS personality"
1517 Say Y here to include the kernel code necessary if you want to run
1518 Acorn RISC OS/Arthur binaries under Linux. This code is still very
1519 experimental; if this sounds frightening, say N and sleep in peace.
1520 You can also say M here to compile this support as a module (which
1521 will be called arthur).
1525 menu "Power management options"
1527 source "kernel/power/Kconfig"
1529 config ARCH_SUSPEND_POSSIBLE
1534 source "net/Kconfig"
1536 source "drivers/Kconfig"
1540 source "arch/arm/Kconfig.debug"
1542 source "security/Kconfig"
1544 source "crypto/Kconfig"
1546 source "lib/Kconfig"