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
311 select ARCH_REQUIRE_GPIOLIB
315 Support for Freescale MXC/iMX-based family of processors
318 bool "Freescale STMP3xxx"
322 select ARCH_REQUIRE_GPIOLIB
324 select GENERIC_CLOCKEVENTS
326 select USB_ARCH_HAS_EHCI
328 Support for systems based on the Freescale 3xxx CPUs.
331 bool "Hilscher NetX based"
334 select GENERIC_CLOCKEVENTS
337 This enables support for systems based on the Hilscher NetX Soc
340 bool "Hynix HMS720x-based"
344 This enables support for systems based on the Hynix HMS720x
347 bool "STMicroelectronics Nomadik"
354 select GENERIC_CLOCKEVENTS
356 select ARCH_REQUIRE_GPIOLIB
358 Support for the Nomadik platform by ST-Ericsson
366 select ARCH_SUPPORTS_MSI
369 Support for Intel's IOP13XX (XScale) family of processors.
378 select ARCH_REQUIRE_GPIOLIB
380 Support for Intel's 80219 and IOP32X (XScale) family of
390 select ARCH_REQUIRE_GPIOLIB
392 Support for Intel's IOP33X (XScale) family of processors.
400 Support for Intel's IXP23xx (XScale) family of processors.
403 bool "IXP2400/2800-based"
408 Support for Intel's IXP2400/2800 (XScale) family of processors.
416 select GENERIC_CLOCKEVENTS
417 select DMABOUNCE if PCI
419 Support for Intel's IXP4XX (XScale) family of processors.
426 Say Y here if you intend to run this kernel on a LinkUp Systems
427 L7200 Software Development Board which uses an ARM720T processor.
428 Information on this board can be obtained at:
430 <http://www.linkupsys.com/>
432 If you have any questions or comments about the Linux kernel port
433 to this board, send e-mail to <sjhill@cotw.com>.
439 select ARCH_REQUIRE_GPIOLIB
441 select GENERIC_CLOCKEVENTS
444 Support for the Marvell Dove SoC 88AP510
447 bool "Marvell Kirkwood"
451 select ARCH_REQUIRE_GPIOLIB
453 select GENERIC_CLOCKEVENTS
456 Support for the following Marvell Kirkwood series SoCs:
457 88F6180, 88F6192 and 88F6281.
460 bool "Marvell Loki (88RC8480)"
463 select GENERIC_CLOCKEVENTS
466 Support for the Marvell Loki (88RC8480) SoC.
469 bool "Marvell MV78xx0"
473 select ARCH_REQUIRE_GPIOLIB
475 select GENERIC_CLOCKEVENTS
478 Support for the following Marvell MV78xx0 series SoCs:
487 select ARCH_REQUIRE_GPIOLIB
489 select GENERIC_CLOCKEVENTS
492 Support for the following Marvell Orion 5x series SoCs:
493 Orion-1 (5181), Orion-VoIP (5181L), Orion-NAS (5182),
494 Orion-2 (5281), Orion-1-90 (6183).
497 bool "Marvell PXA168/910"
500 select ARCH_REQUIRE_GPIOLIB
504 select GENERIC_CLOCKEVENTS
508 Support for Marvell's PXA168/910 processor line.
511 bool "Micrel/Kendin KS8695"
514 select ARCH_REQUIRE_GPIOLIB
516 Support for Micrel/Kendin KS8695 "Centaur" (ARM922T) based
517 System-on-Chip devices.
520 bool "NetSilicon NS9xxx"
524 select GENERIC_CLOCKEVENTS
527 Say Y here if you intend to run this kernel on a NetSilicon NS9xxx
530 <http://www.digi.com/products/microprocessors/index.jsp>
533 bool "Nuvoton W90X900 CPU"
535 select ARCH_REQUIRE_GPIOLIB
540 select GENERIC_CLOCKEVENTS
542 Support for Nuvoton (Winbond logic dept.) ARM9 processor,
543 At present, the w90x900 has been renamed nuc900, regarding
544 the ARM series product line, you can login the following
545 link address to know more.
547 <http://www.nuvoton.com/hq/enu/ProductAndSales/ProductLines/
548 ConsumerElectronicsIC/ARMMicrocontroller/ARMMicrocontroller>
551 bool "Philips Nexperia PNX4008 Mobile"
555 This enables support for Philips PNX4008 mobile platform.
558 bool "PXA2xx/PXA3xx-based"
561 select ARCH_HAS_CPUFREQ
565 select ARCH_REQUIRE_GPIOLIB
567 select GENERIC_CLOCKEVENTS
571 Support for Intel/Marvell's PXA2xx/PXA3xx processor line.
577 select GENERIC_CLOCKEVENTS
579 Support for Qualcomm MSM7K based systems. This runs on the ARM11
580 apps processor of the MSM7K and depends on a shared memory
581 interface to the ARM9 modem processor which runs the baseband stack
582 and controls some vital subsystems (clock and power control, etc).
589 select ARCH_MAY_HAVE_PC_FDC
590 select HAVE_PATA_PLATFORM
593 select ARCH_SPARSEMEM_ENABLE
595 On the Acorn Risc-PC, Linux can support the internal IDE disk and
596 CD-ROM interface, serial and parallel port, and the floppy drive.
602 select ARCH_SPARSEMEM_ENABLE
604 select ARCH_HAS_CPUFREQ
608 select GENERIC_CLOCKEVENTS
611 select ARCH_REQUIRE_GPIOLIB
613 Support for StrongARM 11x0 based boards.
616 bool "Samsung S3C2410, S3C2412, S3C2413, S3C2440, S3C2442, S3C2443"
618 select ARCH_HAS_CPUFREQ
621 Samsung S3C2410X CPU based systems, such as the Simtec Electronics
622 BAST (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or
623 the Samsung SMDK2410 development board (and derivatives).
626 bool "Samsung S3C64XX"
629 select ARCH_HAS_CPUFREQ
631 Samsung S3C64XX series based systems
634 bool "Samsung S5PC1XX"
639 Samsung S5PC1XX series based systems
649 Support for the StrongARM based Digital DNARD machine, also known
650 as "Shark" (<http://www.shark-linux.de/shark.html>).
655 select ARCH_DISCONTIGMEM_ENABLE if !LH7A40X_CONTIGMEM
656 select ARCH_SPARSEMEM_ENABLE if !LH7A40X_CONTIGMEM
658 Say Y here for systems based on one of the Sharp LH7A40X
659 System on a Chip processors. These CPUs include an ARM922T
660 core with a wide array of integrated devices for
661 hand-held and low-power applications.
664 bool "ST-Ericsson U300 Series"
671 select GENERIC_CLOCKEVENTS
676 Support for ST-Ericsson U300 series mobile platforms.
682 select GENERIC_CLOCKEVENTS
684 select ARCH_REQUIRE_GPIOLIB
689 select GENERIC_ALLOCATOR
691 Support for TI's DaVinci platform.
697 select ARCH_REQUIRE_GPIOLIB
698 select ARCH_HAS_CPUFREQ
700 select GENERIC_CLOCKEVENTS
702 Support for TI's OMAP platform (OMAP1 and OMAP2).
705 bool "Broadcom BCMRING"
711 select GENERIC_CLOCKEVENTS
712 select ARCH_WANT_OPTIONAL_GPIOLIB
714 Support for Broadcom's BCMRing platform.
717 bool "ST-Ericsson U8500 Series"
721 select GENERIC_CLOCKEVENTS
724 Support for ST-Ericsson's Ux500 architecture
728 source "arch/arm/mach-clps711x/Kconfig"
730 source "arch/arm/mach-ep93xx/Kconfig"
732 source "arch/arm/mach-footbridge/Kconfig"
734 source "arch/arm/mach-gemini/Kconfig"
736 source "arch/arm/mach-integrator/Kconfig"
738 source "arch/arm/mach-iop32x/Kconfig"
740 source "arch/arm/mach-iop33x/Kconfig"
742 source "arch/arm/mach-iop13xx/Kconfig"
744 source "arch/arm/mach-ixp4xx/Kconfig"
746 source "arch/arm/mach-ixp2000/Kconfig"
748 source "arch/arm/mach-ixp23xx/Kconfig"
750 source "arch/arm/mach-loki/Kconfig"
752 source "arch/arm/mach-mv78xx0/Kconfig"
754 source "arch/arm/mach-pxa/Kconfig"
755 source "arch/arm/plat-pxa/Kconfig"
757 source "arch/arm/mach-mmp/Kconfig"
759 source "arch/arm/mach-sa1100/Kconfig"
761 source "arch/arm/plat-omap/Kconfig"
763 source "arch/arm/mach-omap1/Kconfig"
765 source "arch/arm/mach-omap2/Kconfig"
767 source "arch/arm/mach-orion5x/Kconfig"
769 source "arch/arm/mach-kirkwood/Kconfig"
771 source "arch/arm/mach-dove/Kconfig"
773 source "arch/arm/plat-samsung/Kconfig"
774 source "arch/arm/plat-s3c24xx/Kconfig"
775 source "arch/arm/plat-s3c64xx/Kconfig"
776 source "arch/arm/plat-s3c/Kconfig"
777 source "arch/arm/plat-s5pc1xx/Kconfig"
780 source "arch/arm/mach-s3c2400/Kconfig"
781 source "arch/arm/mach-s3c2410/Kconfig"
782 source "arch/arm/mach-s3c2412/Kconfig"
783 source "arch/arm/mach-s3c2440/Kconfig"
784 source "arch/arm/mach-s3c2442/Kconfig"
785 source "arch/arm/mach-s3c2443/Kconfig"
789 source "arch/arm/mach-s3c6400/Kconfig"
790 source "arch/arm/mach-s3c6410/Kconfig"
793 source "arch/arm/plat-stmp3xxx/Kconfig"
796 source "arch/arm/mach-s5pc100/Kconfig"
799 source "arch/arm/mach-lh7a40x/Kconfig"
801 source "arch/arm/mach-h720x/Kconfig"
803 source "arch/arm/mach-versatile/Kconfig"
805 source "arch/arm/mach-aaec2000/Kconfig"
807 source "arch/arm/mach-realview/Kconfig"
809 source "arch/arm/mach-at91/Kconfig"
811 source "arch/arm/plat-mxc/Kconfig"
813 source "arch/arm/mach-nomadik/Kconfig"
814 source "arch/arm/plat-nomadik/Kconfig"
816 source "arch/arm/mach-netx/Kconfig"
818 source "arch/arm/mach-ns9xxx/Kconfig"
820 source "arch/arm/mach-davinci/Kconfig"
822 source "arch/arm/mach-ks8695/Kconfig"
824 source "arch/arm/mach-msm/Kconfig"
826 source "arch/arm/mach-u300/Kconfig"
828 source "arch/arm/mach-w90x900/Kconfig"
830 source "arch/arm/mach-bcmring/Kconfig"
832 source "arch/arm/mach-ux500/Kconfig"
834 # Definitions to make life easier
840 select GENERIC_CLOCKEVENTS
849 source arch/arm/mm/Kconfig
852 bool "Enable iWMMXt support"
853 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK
854 default y if PXA27x || PXA3xx || ARCH_MMP
856 Enable support for iWMMXt context switching at run time if
857 running on a CPU that supports it.
859 # bool 'Use XScale PMU as timer source' CONFIG_XSCALE_PMU_TIMER
862 depends on CPU_XSCALE && !XSCALE_PMU_TIMER
866 source "arch/arm/Kconfig-nommu"
869 config ARM_ERRATA_411920
870 bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
871 depends on CPU_V6 && !SMP
873 Invalidation of the Instruction Cache operation can
874 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
875 It does not affect the MPCore. This option enables the ARM Ltd.
876 recommended workaround.
878 config ARM_ERRATA_430973
879 bool "ARM errata: Stale prediction on replaced interworking branch"
882 This option enables the workaround for the 430973 Cortex-A8
883 (r1p0..r1p2) erratum. If a code sequence containing an ARM/Thumb
884 interworking branch is replaced with another code sequence at the
885 same virtual address, whether due to self-modifying code or virtual
886 to physical address re-mapping, Cortex-A8 does not recover from the
887 stale interworking branch prediction. This results in Cortex-A8
888 executing the new code sequence in the incorrect ARM or Thumb state.
889 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
890 and also flushes the branch target cache at every context switch.
891 Note that setting specific bits in the ACTLR register may not be
892 available in non-secure mode.
894 config ARM_ERRATA_458693
895 bool "ARM errata: Processor deadlock when a false hazard is created"
898 This option enables the workaround for the 458693 Cortex-A8 (r2p0)
899 erratum. For very specific sequences of memory operations, it is
900 possible for a hazard condition intended for a cache line to instead
901 be incorrectly associated with a different cache line. This false
902 hazard might then cause a processor deadlock. The workaround enables
903 the L1 caching of the NEON accesses and disables the PLD instruction
904 in the ACTLR register. Note that setting specific bits in the ACTLR
905 register may not be available in non-secure mode.
907 config ARM_ERRATA_460075
908 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
911 This option enables the workaround for the 460075 Cortex-A8 (r2p0)
912 erratum. Any asynchronous access to the L2 cache may encounter a
913 situation in which recent store transactions to the L2 cache are lost
914 and overwritten with stale memory contents from external memory. The
915 workaround disables the write-allocate mode for the L2 cache via the
916 ACTLR register. Note that setting specific bits in the ACTLR register
917 may not be available in non-secure mode.
921 source "arch/arm/common/Kconfig"
923 config FORCE_MAX_ZONEORDER
936 Find out whether you have ISA slots on your motherboard. ISA is the
937 name of a bus system, i.e. the way the CPU talks to the other stuff
938 inside your box. Other bus systems are PCI, EISA, MicroChannel
939 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
940 newer boards don't support it. If you have ISA, say Y, otherwise N.
942 # Select ISA DMA controller support
947 # Select ISA DMA interface
952 bool "PCI support" if ARCH_INTEGRATOR_AP || ARCH_VERSATILE_PB || ARCH_IXP4XX || ARCH_KS8695 || MACH_ARMCORE
954 Find out whether you have a PCI motherboard. PCI is the name of a
955 bus system, i.e. the way the CPU talks to the other stuff inside
956 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
957 VESA. If you have PCI, say Y, otherwise N.
962 # Select the host bridge type
963 config PCI_HOST_VIA82C505
965 depends on PCI && ARCH_SHARK
968 config PCI_HOST_ITE8152
970 depends on PCI && MACH_ARMCORE
974 source "drivers/pci/Kconfig"
976 source "drivers/pcmcia/Kconfig"
980 menu "Kernel Features"
982 source "kernel/time/Kconfig"
985 bool "Symmetric Multi-Processing (EXPERIMENTAL)"
986 depends on EXPERIMENTAL && (REALVIEW_EB_ARM11MP || REALVIEW_EB_A9MP ||\
987 MACH_REALVIEW_PB11MP || MACH_REALVIEW_PBX || ARCH_OMAP4 || ARCH_U8500)
988 depends on GENERIC_CLOCKEVENTS
989 select USE_GENERIC_SMP_HELPERS
990 select HAVE_ARM_SCU if (ARCH_REALVIEW || ARCH_OMAP4 || ARCH_U8500)
992 This enables support for systems with more than one CPU. If you have
993 a system with only one CPU, like most personal computers, say N. If
994 you have a system with more than one CPU, say Y.
996 If you say N here, the kernel will run on single and multiprocessor
997 machines, but will use only one CPU of a multiprocessor machine. If
998 you say Y here, the kernel will run on many, but not all, single
999 processor machines. On a single processor machine, the kernel will
1000 run faster if you say N here.
1002 See also <file:Documentation/i386/IO-APIC.txt>,
1003 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
1004 <http://www.linuxdoc.org/docs.html#howto>.
1006 If you don't know what to do here, say N.
1012 This option enables support for the ARM system coherency unit
1018 This options enables support for the ARM timer and watchdog unit
1021 prompt "Memory split"
1024 Select the desired split between kernel and user memory.
1026 If you are not absolutely sure what you are doing, leave this
1030 bool "3G/1G user/kernel split"
1032 bool "2G/2G user/kernel split"
1034 bool "1G/3G user/kernel split"
1039 default 0x40000000 if VMSPLIT_1G
1040 default 0x80000000 if VMSPLIT_2G
1044 int "Maximum number of CPUs (2-32)"
1050 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
1051 depends on SMP && HOTPLUG && EXPERIMENTAL
1053 Say Y here to experiment with turning CPUs off and on. CPUs
1054 can be controlled through /sys/devices/system/cpu.
1057 bool "Use local timer interrupts"
1058 depends on SMP && (REALVIEW_EB_ARM11MP || MACH_REALVIEW_PB11MP || \
1059 REALVIEW_EB_A9MP || MACH_REALVIEW_PBX || ARCH_OMAP4 || ARCH_U8500)
1061 select HAVE_ARM_TWD if (ARCH_REALVIEW || ARCH_OMAP4 || ARCH_U8500)
1063 Enable support for local timers on SMP platforms, rather then the
1064 legacy IPI broadcast method. Local timers allows the system
1065 accounting to be spread across the timer interval, preventing a
1066 "thundering herd" at every timer tick.
1068 source kernel/Kconfig.preempt
1072 default 128 if ARCH_L7200
1073 default 200 if ARCH_EBSA110 || ARCH_S3C2410
1074 default OMAP_32K_TIMER_HZ if ARCH_OMAP && OMAP_32K_TIMER
1075 default AT91_TIMER_HZ if ARCH_AT91
1078 config THUMB2_KERNEL
1079 bool "Compile the kernel in Thumb-2 mode"
1080 depends on CPU_V7 && EXPERIMENTAL
1082 select ARM_ASM_UNIFIED
1084 By enabling this option, the kernel will be compiled in
1085 Thumb-2 mode. A compiler/assembler that understand the unified
1086 ARM-Thumb syntax is needed.
1090 config ARM_ASM_UNIFIED
1094 bool "Use the ARM EABI to compile the kernel"
1096 This option allows for the kernel to be compiled using the latest
1097 ARM ABI (aka EABI). This is only useful if you are using a user
1098 space environment that is also compiled with EABI.
1100 Since there are major incompatibilities between the legacy ABI and
1101 EABI, especially with regard to structure member alignment, this
1102 option also changes the kernel syscall calling convention to
1103 disambiguate both ABIs and allow for backward compatibility support
1104 (selected with CONFIG_OABI_COMPAT).
1106 To use this you need GCC version 4.0.0 or later.
1109 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1110 depends on AEABI && EXPERIMENTAL
1113 This option preserves the old syscall interface along with the
1114 new (ARM EABI) one. It also provides a compatibility layer to
1115 intercept syscalls that have structure arguments which layout
1116 in memory differs between the legacy ABI and the new ARM EABI
1117 (only for non "thumb" binaries). This option adds a tiny
1118 overhead to all syscalls and produces a slightly larger kernel.
1119 If you know you'll be using only pure EABI user space then you
1120 can say N here. If this option is not selected and you attempt
1121 to execute a legacy ABI binary then the result will be
1122 UNPREDICTABLE (in fact it can be predicted that it won't work
1123 at all). If in doubt say Y.
1125 config ARCH_HAS_HOLES_MEMORYMODEL
1128 # Discontigmem is deprecated
1129 config ARCH_DISCONTIGMEM_ENABLE
1132 config ARCH_SPARSEMEM_ENABLE
1135 config ARCH_SPARSEMEM_DEFAULT
1136 def_bool ARCH_SPARSEMEM_ENABLE
1138 config ARCH_SELECT_MEMORY_MODEL
1139 def_bool ARCH_DISCONTIGMEM_ENABLE && ARCH_SPARSEMEM_ENABLE
1143 default "4" if ARCH_LH7A40X
1145 depends on NEED_MULTIPLE_NODES
1148 bool "High Memory Support (EXPERIMENTAL)"
1149 depends on MMU && EXPERIMENTAL
1151 The address space of ARM processors is only 4 Gigabytes large
1152 and it has to accommodate user address space, kernel address
1153 space as well as some memory mapped IO. That means that, if you
1154 have a large amount of physical memory and/or IO, not all of the
1155 memory can be "permanently mapped" by the kernel. The physical
1156 memory that is not permanently mapped is called "high memory".
1158 Depending on the selected kernel/user memory split, minimum
1159 vmalloc space and actual amount of RAM, you may not need this
1160 option which should result in a slightly faster kernel.
1165 bool "Allocate 2nd-level pagetables from highmem"
1167 depends on !OUTER_CACHE
1172 bool "Timer and CPU usage LEDs"
1173 depends on ARCH_CDB89712 || ARCH_EBSA110 || \
1174 ARCH_EBSA285 || ARCH_INTEGRATOR || \
1175 ARCH_LUBBOCK || MACH_MAINSTONE || ARCH_NETWINDER || \
1176 ARCH_OMAP || ARCH_P720T || ARCH_PXA_IDP || \
1177 ARCH_SA1100 || ARCH_SHARK || ARCH_VERSATILE || \
1178 ARCH_AT91 || ARCH_DAVINCI || \
1179 ARCH_KS8695 || MACH_RD88F5182 || ARCH_REALVIEW
1181 If you say Y here, the LEDs on your machine will be used
1182 to provide useful information about your current system status.
1184 If you are compiling a kernel for a NetWinder or EBSA-285, you will
1185 be able to select which LEDs are active using the options below. If
1186 you are compiling a kernel for the EBSA-110 or the LART however, the
1187 red LED will simply flash regularly to indicate that the system is
1188 still functional. It is safe to say Y here if you have a CATS
1189 system, but the driver will do nothing.
1192 bool "Timer LED" if (!ARCH_CDB89712 && !ARCH_OMAP) || \
1193 OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1194 || MACH_OMAP_PERSEUS2
1196 depends on !GENERIC_CLOCKEVENTS
1197 default y if ARCH_EBSA110
1199 If you say Y here, one of the system LEDs (the green one on the
1200 NetWinder, the amber one on the EBSA285, or the red one on the LART)
1201 will flash regularly to indicate that the system is still
1202 operational. This is mainly useful to kernel hackers who are
1203 debugging unstable kernels.
1205 The LART uses the same LED for both Timer LED and CPU usage LED
1206 functions. You may choose to use both, but the Timer LED function
1207 will overrule the CPU usage LED.
1210 bool "CPU usage LED" if (!ARCH_CDB89712 && !ARCH_EBSA110 && \
1212 || OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1213 || MACH_OMAP_PERSEUS2
1216 If you say Y here, the red LED will be used to give a good real
1217 time indication of CPU usage, by lighting whenever the idle task
1218 is not currently executing.
1220 The LART uses the same LED for both Timer LED and CPU usage LED
1221 functions. You may choose to use both, but the Timer LED function
1222 will overrule the CPU usage LED.
1224 config ALIGNMENT_TRAP
1226 depends on CPU_CP15_MMU
1227 default y if !ARCH_EBSA110
1229 ARM processors cannot fetch/store information which is not
1230 naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1231 address divisible by 4. On 32-bit ARM processors, these non-aligned
1232 fetch/store instructions will be emulated in software if you say
1233 here, which has a severe performance impact. This is necessary for
1234 correct operation of some network protocols. With an IP-only
1235 configuration it is safe to say N, otherwise say Y.
1237 config UACCESS_WITH_MEMCPY
1238 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user() (EXPERIMENTAL)"
1239 depends on MMU && EXPERIMENTAL
1240 default y if CPU_FEROCEON
1242 Implement faster copy_to_user and clear_user methods for CPU
1243 cores where a 8-word STM instruction give significantly higher
1244 memory write throughput than a sequence of individual 32bit stores.
1246 A possible side effect is a slight increase in scheduling latency
1247 between threads sharing the same address space if they invoke
1248 such copy operations with large buffers.
1250 However, if the CPU data cache is using a write-allocate mode,
1251 this option is unlikely to provide any performance gain.
1257 # Compressed boot loader in ROM. Yes, we really want to ask about
1258 # TEXT and BSS so we preserve their values in the config files.
1259 config ZBOOT_ROM_TEXT
1260 hex "Compressed ROM boot loader base address"
1263 The physical address at which the ROM-able zImage is to be
1264 placed in the target. Platforms which normally make use of
1265 ROM-able zImage formats normally set this to a suitable
1266 value in their defconfig file.
1268 If ZBOOT_ROM is not enabled, this has no effect.
1270 config ZBOOT_ROM_BSS
1271 hex "Compressed ROM boot loader BSS address"
1274 The base address of an area of read/write memory in the target
1275 for the ROM-able zImage which must be available while the
1276 decompressor is running. It must be large enough to hold the
1277 entire decompressed kernel plus an additional 128 KiB.
1278 Platforms which normally make use of ROM-able zImage formats
1279 normally set this to a suitable value in their defconfig file.
1281 If ZBOOT_ROM is not enabled, this has no effect.
1284 bool "Compressed boot loader in ROM/flash"
1285 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1287 Say Y here if you intend to execute your compressed kernel image
1288 (zImage) directly from ROM or flash. If unsure, say N.
1291 string "Default kernel command string"
1294 On some architectures (EBSA110 and CATS), there is currently no way
1295 for the boot loader to pass arguments to the kernel. For these
1296 architectures, you should supply some command-line options at build
1297 time by entering them here. As a minimum, you should specify the
1298 memory size and the root device (e.g., mem=64M root=/dev/nfs).
1301 bool "Kernel Execute-In-Place from ROM"
1302 depends on !ZBOOT_ROM
1304 Execute-In-Place allows the kernel to run from non-volatile storage
1305 directly addressable by the CPU, such as NOR flash. This saves RAM
1306 space since the text section of the kernel is not loaded from flash
1307 to RAM. Read-write sections, such as the data section and stack,
1308 are still copied to RAM. The XIP kernel is not compressed since
1309 it has to run directly from flash, so it will take more space to
1310 store it. The flash address used to link the kernel object files,
1311 and for storing it, is configuration dependent. Therefore, if you
1312 say Y here, you must know the proper physical address where to
1313 store the kernel image depending on your own flash memory usage.
1315 Also note that the make target becomes "make xipImage" rather than
1316 "make zImage" or "make Image". The final kernel binary to put in
1317 ROM memory will be arch/arm/boot/xipImage.
1321 config XIP_PHYS_ADDR
1322 hex "XIP Kernel Physical Location"
1323 depends on XIP_KERNEL
1324 default "0x00080000"
1326 This is the physical address in your flash memory the kernel will
1327 be linked for and stored to. This address is dependent on your
1331 bool "Kexec system call (EXPERIMENTAL)"
1332 depends on EXPERIMENTAL
1334 kexec is a system call that implements the ability to shutdown your
1335 current kernel, and to start another kernel. It is like a reboot
1336 but it is independent of the system firmware. And like a reboot
1337 you can start any kernel with it, not just Linux.
1339 It is an ongoing process to be certain the hardware in a machine
1340 is properly shutdown, so do not be surprised if this code does not
1341 initially work for you. It may help to enable device hotplugging
1345 bool "Export atags in procfs"
1349 Should the atags used to boot the kernel be exported in an "atags"
1350 file in procfs. Useful with kexec.
1354 menu "CPU Power Management"
1358 source "drivers/cpufreq/Kconfig"
1360 config CPU_FREQ_SA1100
1363 config CPU_FREQ_SA1110
1366 config CPU_FREQ_INTEGRATOR
1367 tristate "CPUfreq driver for ARM Integrator CPUs"
1368 depends on ARCH_INTEGRATOR && CPU_FREQ
1371 This enables the CPUfreq driver for ARM Integrator CPUs.
1373 For details, take a look at <file:Documentation/cpu-freq>.
1379 depends on CPU_FREQ && ARCH_PXA && PXA25x
1381 select CPU_FREQ_DEFAULT_GOV_USERSPACE
1383 config CPU_FREQ_S3C64XX
1384 bool "CPUfreq support for Samsung S3C64XX CPUs"
1385 depends on CPU_FREQ && CPU_S3C6410
1390 Internal configuration node for common cpufreq on Samsung SoC
1392 config CPU_FREQ_S3C24XX
1393 bool "CPUfreq driver for Samsung S3C24XX series CPUs"
1394 depends on ARCH_S3C2410 && CPU_FREQ && EXPERIMENTAL
1397 This enables the CPUfreq driver for the Samsung S3C24XX family
1400 For details, take a look at <file:Documentation/cpu-freq>.
1404 config CPU_FREQ_S3C24XX_PLL
1405 bool "Support CPUfreq changing of PLL frequency"
1406 depends on CPU_FREQ_S3C24XX && EXPERIMENTAL
1408 Compile in support for changing the PLL frequency from the
1409 S3C24XX series CPUfreq driver. The PLL takes time to settle
1410 after a frequency change, so by default it is not enabled.
1412 This also means that the PLL tables for the selected CPU(s) will
1413 be built which may increase the size of the kernel image.
1415 config CPU_FREQ_S3C24XX_DEBUG
1416 bool "Debug CPUfreq Samsung driver core"
1417 depends on CPU_FREQ_S3C24XX
1419 Enable s3c_freq_dbg for the Samsung S3C CPUfreq core
1421 config CPU_FREQ_S3C24XX_IODEBUG
1422 bool "Debug CPUfreq Samsung driver IO timing"
1423 depends on CPU_FREQ_S3C24XX
1425 Enable s3c_freq_iodbg for the Samsung S3C CPUfreq core
1427 config CPU_FREQ_S3C24XX_DEBUGFS
1428 bool "Export debugfs for CPUFreq"
1429 depends on CPU_FREQ_S3C24XX && DEBUG_FS
1431 Export status information via debugfs.
1435 source "drivers/cpuidle/Kconfig"
1439 menu "Floating point emulation"
1441 comment "At least one emulation must be selected"
1444 bool "NWFPE math emulation"
1445 depends on !AEABI || OABI_COMPAT
1447 Say Y to include the NWFPE floating point emulator in the kernel.
1448 This is necessary to run most binaries. Linux does not currently
1449 support floating point hardware so you need to say Y here even if
1450 your machine has an FPA or floating point co-processor podule.
1452 You may say N here if you are going to load the Acorn FPEmulator
1453 early in the bootup.
1456 bool "Support extended precision"
1457 depends on FPE_NWFPE
1459 Say Y to include 80-bit support in the kernel floating-point
1460 emulator. Otherwise, only 32 and 64-bit support is compiled in.
1461 Note that gcc does not generate 80-bit operations by default,
1462 so in most cases this option only enlarges the size of the
1463 floating point emulator without any good reason.
1465 You almost surely want to say N here.
1468 bool "FastFPE math emulation (EXPERIMENTAL)"
1469 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3 && EXPERIMENTAL
1471 Say Y here to include the FAST floating point emulator in the kernel.
1472 This is an experimental much faster emulator which now also has full
1473 precision for the mantissa. It does not support any exceptions.
1474 It is very simple, and approximately 3-6 times faster than NWFPE.
1476 It should be sufficient for most programs. It may be not suitable
1477 for scientific calculations, but you have to check this for yourself.
1478 If you do not feel you need a faster FP emulation you should better
1482 bool "VFP-format floating point maths"
1483 depends on CPU_V6 || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
1485 Say Y to include VFP support code in the kernel. This is needed
1486 if your hardware includes a VFP unit.
1488 Please see <file:Documentation/arm/VFP/release-notes.txt> for
1489 release notes and additional status information.
1491 Say N if your target does not have VFP hardware.
1499 bool "Advanced SIMD (NEON) Extension support"
1500 depends on VFPv3 && CPU_V7
1502 Say Y to include support code for NEON, the ARMv7 Advanced SIMD
1507 menu "Userspace binary formats"
1509 source "fs/Kconfig.binfmt"
1512 tristate "RISC OS personality"
1515 Say Y here to include the kernel code necessary if you want to run
1516 Acorn RISC OS/Arthur binaries under Linux. This code is still very
1517 experimental; if this sounds frightening, say N and sleep in peace.
1518 You can also say M here to compile this support as a module (which
1519 will be called arthur).
1523 menu "Power management options"
1525 source "kernel/power/Kconfig"
1527 config ARCH_SUSPEND_POSSIBLE
1532 source "net/Kconfig"
1534 source "drivers/Kconfig"
1538 source "arch/arm/Kconfig.debug"
1540 source "security/Kconfig"
1542 source "crypto/Kconfig"
1544 source "lib/Kconfig"