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
35 config HAVE_SCHED_CLOCK
44 config GENERIC_CLOCKEVENTS
47 config GENERIC_CLOCKEVENTS_BROADCAST
49 depends on GENERIC_CLOCKEVENTS
50 default y if SMP && !LOCAL_TIMERS
54 select GENERIC_ALLOCATOR
62 The Extended Industry Standard Architecture (EISA) bus was
63 developed as an open alternative to the IBM MicroChannel bus.
65 The EISA bus provided some of the features of the IBM MicroChannel
66 bus while maintaining backward compatibility with cards made for
67 the older ISA bus. The EISA bus saw limited use between 1988 and
68 1995 when it was made obsolete by the PCI bus.
70 Say Y here if you are building a kernel for an EISA-based machine.
80 MicroChannel Architecture is found in some IBM PS/2 machines and
81 laptops. It is a bus system similar to PCI or ISA. See
82 <file:Documentation/mca.txt> (and especially the web page given
83 there) before attempting to build an MCA bus kernel.
85 config GENERIC_HARDIRQS
89 config STACKTRACE_SUPPORT
93 config HAVE_LATENCYTOP_SUPPORT
98 config LOCKDEP_SUPPORT
102 config TRACE_IRQFLAGS_SUPPORT
106 config HARDIRQS_SW_RESEND
110 config GENERIC_IRQ_PROBE
114 config GENERIC_LOCKBREAK
117 depends on SMP && PREEMPT
119 config RWSEM_GENERIC_SPINLOCK
123 config RWSEM_XCHGADD_ALGORITHM
126 config ARCH_HAS_ILOG2_U32
129 config ARCH_HAS_ILOG2_U64
132 config ARCH_HAS_CPUFREQ
135 Internal node to signify that the ARCH has CPUFREQ support
136 and that the relevant menu configurations are displayed for
139 config GENERIC_HWEIGHT
143 config GENERIC_CALIBRATE_DELAY
147 config ARCH_MAY_HAVE_PC_FDC
153 config GENERIC_ISA_DMA
162 config GENERIC_HARDIRQS_NO__DO_IRQ
167 config OPROFILE_ARMV6
169 depends on CPU_V6 && !SMP
170 select OPROFILE_ARM11_CORE
172 config OPROFILE_MPCORE
174 depends on CPU_V6 && SMP
175 select OPROFILE_ARM11_CORE
177 config OPROFILE_ARM11_CORE
180 config OPROFILE_ARMV7
182 depends on CPU_V7 && !SMP
189 default 0xffff0000 if MMU || CPU_HIGH_VECTOR
190 default DRAM_BASE if REMAP_VECTORS_TO_RAM
193 The base address of exception vectors.
195 source "init/Kconfig"
197 source "kernel/Kconfig.freezer"
202 bool "MMU-based Paged Memory Management Support"
205 Select if you want MMU-based virtualised addressing space
206 support by paged memory management. If unsure, say 'Y'.
209 prompt "ARM system type"
210 default ARCH_VERSATILE
213 bool "Agilent AAEC-2000 based"
218 This enables support for systems based on the Agilent AAEC-2000
220 config ARCH_INTEGRATOR
221 bool "ARM Ltd. Integrator family"
223 select ARCH_HAS_CPUFREQ
228 Support for ARM's Integrator platform.
231 bool "ARM Ltd. RealView family"
237 select GENERIC_CLOCKEVENTS
238 select ARCH_WANT_OPTIONAL_GPIOLIB
240 This enables support for ARM Ltd RealView boards.
242 config ARCH_VERSATILE
243 bool "ARM Ltd. Versatile family"
250 select GENERIC_CLOCKEVENTS
251 select ARCH_WANT_OPTIONAL_GPIOLIB
253 This enables support for ARM Ltd Versatile board.
258 select ARCH_REQUIRE_GPIOLIB
261 This enables support for systems based on the Atmel AT91RM9200,
262 AT91SAM9 and AT91CAP9 processors.
265 bool "Cirrus Logic CLPS711x/EP721x-based"
268 Support for Cirrus Logic 711x/721x based boards.
271 bool "Cortina Systems Gemini"
274 select ARCH_REQUIRE_GPIOLIB
276 Support for the Cortina Systems Gemini family SoCs
284 This is an evaluation board for the StrongARM processor available
285 from Digital. It has limited hardware on-board, including an
286 Ethernet interface, two PCMCIA sockets, two serial ports and a
297 select ARCH_REQUIRE_GPIOLIB
298 select ARCH_HAS_HOLES_MEMORYMODEL
300 This enables support for the Cirrus EP93xx series of CPUs.
302 config ARCH_FOOTBRIDGE
307 Support for systems based on the DC21285 companion chip
308 ("FootBridge"), such as the Simtec CATS and the Rebel NetWinder.
311 bool "Freescale MXC/iMX-based"
313 select GENERIC_CLOCKEVENTS
316 select ARCH_REQUIRE_GPIOLIB
319 Support for Freescale MXC/iMX-based family of processors
322 bool "Freescale STMP3xxx"
326 select ARCH_REQUIRE_GPIOLIB
328 select GENERIC_CLOCKEVENTS
330 select USB_ARCH_HAS_EHCI
332 Support for systems based on the Freescale 3xxx CPUs.
335 bool "Hilscher NetX based"
338 select GENERIC_CLOCKEVENTS
341 This enables support for systems based on the Hilscher NetX Soc
344 bool "Hynix HMS720x-based"
348 This enables support for systems based on the Hynix HMS720x
351 bool "STMicroelectronics Nomadik"
358 select GENERIC_CLOCKEVENTS
360 select ARCH_REQUIRE_GPIOLIB
362 Support for the Nomadik platform by ST-Ericsson
370 select ARCH_SUPPORTS_MSI
373 Support for Intel's IOP13XX (XScale) family of processors.
382 select ARCH_REQUIRE_GPIOLIB
384 Support for Intel's 80219 and IOP32X (XScale) family of
394 select ARCH_REQUIRE_GPIOLIB
396 Support for Intel's IOP33X (XScale) family of processors.
404 Support for Intel's IXP23xx (XScale) family of processors.
407 bool "IXP2400/2800-based"
412 Support for Intel's IXP2400/2800 (XScale) family of processors.
420 select GENERIC_CLOCKEVENTS
421 select DMABOUNCE if PCI
423 Support for Intel's IXP4XX (XScale) family of processors.
430 Say Y here if you intend to run this kernel on a LinkUp Systems
431 L7200 Software Development Board which uses an ARM720T processor.
432 Information on this board can be obtained at:
434 <http://www.linkupsys.com/>
436 If you have any questions or comments about the Linux kernel port
437 to this board, send e-mail to <sjhill@cotw.com>.
440 bool "Marvell Kirkwood"
444 select ARCH_REQUIRE_GPIOLIB
446 select GENERIC_CLOCKEVENTS
449 Support for the following Marvell Kirkwood series SoCs:
450 88F6180, 88F6192 and 88F6281.
453 bool "Marvell Loki (88RC8480)"
456 select GENERIC_CLOCKEVENTS
459 Support for the Marvell Loki (88RC8480) SoC.
462 bool "Marvell MV78xx0"
466 select ARCH_REQUIRE_GPIOLIB
468 select GENERIC_CLOCKEVENTS
471 Support for the following Marvell MV78xx0 series SoCs:
480 select ARCH_REQUIRE_GPIOLIB
482 select GENERIC_CLOCKEVENTS
485 Support for the following Marvell Orion 5x series SoCs:
486 Orion-1 (5181), Orion-VoIP (5181L), Orion-NAS (5182),
487 Orion-2 (5281), Orion-1-90 (6183).
490 bool "Marvell PXA168/910"
493 select ARCH_REQUIRE_GPIOLIB
497 select GENERIC_CLOCKEVENTS
501 Support for Marvell's PXA168/910 processor line.
504 bool "Micrel/Kendin KS8695"
507 select ARCH_REQUIRE_GPIOLIB
509 Support for Micrel/Kendin KS8695 "Centaur" (ARM922T) based
510 System-on-Chip devices.
513 bool "NetSilicon NS9xxx"
517 select GENERIC_CLOCKEVENTS
520 Say Y here if you intend to run this kernel on a NetSilicon NS9xxx
523 <http://www.digi.com/products/microprocessors/index.jsp>
526 bool "Nuvoton W90X900 CPU"
528 select ARCH_REQUIRE_GPIOLIB
533 select GENERIC_CLOCKEVENTS
535 Support for Nuvoton (Winbond logic dept.) ARM9 processor,
536 At present, the w90x900 has been renamed nuc900, regarding
537 the ARM series product line, you can login the following
538 link address to know more.
540 <http://www.nuvoton.com/hq/enu/ProductAndSales/ProductLines/
541 ConsumerElectronicsIC/ARMMicrocontroller/ARMMicrocontroller>
544 bool "Philips Nexperia PNX4008 Mobile"
548 This enables support for Philips PNX4008 mobile platform.
551 bool "PXA2xx/PXA3xx-based"
554 select ARCH_HAS_CPUFREQ
558 select ARCH_REQUIRE_GPIOLIB
560 select GENERIC_CLOCKEVENTS
564 Support for Intel/Marvell's PXA2xx/PXA3xx processor line.
570 select GENERIC_CLOCKEVENTS
572 Support for Qualcomm MSM7K based systems. This runs on the ARM11
573 apps processor of the MSM7K and depends on a shared memory
574 interface to the ARM9 modem processor which runs the baseband stack
575 and controls some vital subsystems (clock and power control, etc).
582 select ARCH_MAY_HAVE_PC_FDC
583 select HAVE_PATA_PLATFORM
586 select ARCH_SPARSEMEM_ENABLE
588 On the Acorn Risc-PC, Linux can support the internal IDE disk and
589 CD-ROM interface, serial and parallel port, and the floppy drive.
595 select ARCH_SPARSEMEM_ENABLE
597 select ARCH_HAS_CPUFREQ
600 select GENERIC_CLOCKEVENTS
603 select ARCH_REQUIRE_GPIOLIB
605 Support for StrongARM 11x0 based boards.
608 bool "Samsung S3C2410, S3C2412, S3C2413, S3C2440, S3C2442, S3C2443"
610 select ARCH_HAS_CPUFREQ
613 Samsung S3C2410X CPU based systems, such as the Simtec Electronics
614 BAST (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or
615 the Samsung SMDK2410 development board (and derivatives).
618 bool "Samsung S3C64XX"
621 select ARCH_HAS_CPUFREQ
623 Samsung S3C64XX series based systems
626 bool "Samsung S5PC1XX"
631 Samsung S5PC1XX series based systems
641 Support for the StrongARM based Digital DNARD machine, also known
642 as "Shark" (<http://www.shark-linux.de/shark.html>).
647 select ARCH_DISCONTIGMEM_ENABLE if !LH7A40X_CONTIGMEM
648 select ARCH_SPARSEMEM_ENABLE if !LH7A40X_CONTIGMEM
650 Say Y here for systems based on one of the Sharp LH7A40X
651 System on a Chip processors. These CPUs include an ARM922T
652 core with a wide array of integrated devices for
653 hand-held and low-power applications.
656 bool "ST-Ericsson U300 Series"
663 select GENERIC_CLOCKEVENTS
668 Support for ST-Ericsson U300 series mobile platforms.
674 select GENERIC_CLOCKEVENTS
676 select ARCH_REQUIRE_GPIOLIB
681 select GENERIC_ALLOCATOR
683 Support for TI's DaVinci platform.
689 select ARCH_REQUIRE_GPIOLIB
690 select ARCH_HAS_CPUFREQ
692 select GENERIC_CLOCKEVENTS
694 Support for TI's OMAP platform (OMAP1 and OMAP2).
697 bool "Broadcom BCMRING"
703 select GENERIC_CLOCKEVENTS
704 select ARCH_WANT_OPTIONAL_GPIOLIB
706 Support for Broadcom's BCMRing platform.
709 bool "Rockchip soc rk2818"
715 select ARCH_HAS_CPUFREQ
717 select GENERIC_CLOCKEVENTS
718 select ARCH_REQUIRE_GPIOLIB
720 Support for Rockchip RK2818 soc.
723 bool "Rockchip Soc Rk29"
727 select HAVE_SCHED_CLOCK
728 select ARCH_HAS_CPUFREQ
730 select GENERIC_CLOCKEVENTS
731 select ARCH_REQUIRE_GPIOLIB
735 Support for Rockchip RK29 soc.
739 source "arch/arm/mach-clps711x/Kconfig"
741 source "arch/arm/mach-ep93xx/Kconfig"
743 source "arch/arm/mach-footbridge/Kconfig"
745 source "arch/arm/mach-gemini/Kconfig"
747 source "arch/arm/mach-integrator/Kconfig"
749 source "arch/arm/mach-iop32x/Kconfig"
751 source "arch/arm/mach-iop33x/Kconfig"
753 source "arch/arm/mach-iop13xx/Kconfig"
755 source "arch/arm/mach-ixp4xx/Kconfig"
757 source "arch/arm/mach-ixp2000/Kconfig"
759 source "arch/arm/mach-ixp23xx/Kconfig"
761 source "arch/arm/mach-loki/Kconfig"
763 source "arch/arm/mach-mv78xx0/Kconfig"
765 source "arch/arm/mach-pxa/Kconfig"
766 source "arch/arm/plat-pxa/Kconfig"
768 source "arch/arm/mach-mmp/Kconfig"
770 source "arch/arm/mach-sa1100/Kconfig"
772 source "arch/arm/plat-omap/Kconfig"
774 source "arch/arm/mach-omap1/Kconfig"
776 source "arch/arm/mach-omap2/Kconfig"
778 source "arch/arm/mach-orion5x/Kconfig"
780 source "arch/arm/mach-kirkwood/Kconfig"
782 source "arch/arm/plat-s3c24xx/Kconfig"
783 source "arch/arm/plat-s3c64xx/Kconfig"
784 source "arch/arm/plat-s3c/Kconfig"
785 source "arch/arm/plat-s5pc1xx/Kconfig"
788 source "arch/arm/mach-s3c2400/Kconfig"
789 source "arch/arm/mach-s3c2410/Kconfig"
790 source "arch/arm/mach-s3c2412/Kconfig"
791 source "arch/arm/mach-s3c2440/Kconfig"
792 source "arch/arm/mach-s3c2442/Kconfig"
793 source "arch/arm/mach-s3c2443/Kconfig"
797 source "arch/arm/mach-s3c6400/Kconfig"
798 source "arch/arm/mach-s3c6410/Kconfig"
801 source "arch/arm/plat-stmp3xxx/Kconfig"
804 source "arch/arm/mach-s5pc100/Kconfig"
807 source "arch/arm/mach-lh7a40x/Kconfig"
809 source "arch/arm/mach-h720x/Kconfig"
811 source "arch/arm/mach-versatile/Kconfig"
813 source "arch/arm/mach-aaec2000/Kconfig"
815 source "arch/arm/mach-realview/Kconfig"
817 source "arch/arm/mach-at91/Kconfig"
819 source "arch/arm/plat-mxc/Kconfig"
821 source "arch/arm/mach-nomadik/Kconfig"
823 source "arch/arm/mach-netx/Kconfig"
825 source "arch/arm/mach-ns9xxx/Kconfig"
827 source "arch/arm/mach-davinci/Kconfig"
829 source "arch/arm/mach-ks8695/Kconfig"
831 source "arch/arm/mach-msm/Kconfig"
833 source "arch/arm/mach-u300/Kconfig"
835 source "arch/arm/mach-w90x900/Kconfig"
837 source "arch/arm/mach-bcmring/Kconfig"
839 source "arch/arm/mach-rk2818/Kconfig"
841 source "arch/arm/mach-rk29/Kconfig"
843 # Definitions to make life easier
856 source arch/arm/mm/Kconfig
859 bool "Enable iWMMXt support"
860 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK
861 default y if PXA27x || PXA3xx || ARCH_MMP
863 Enable support for iWMMXt context switching at run time if
864 running on a CPU that supports it.
866 # bool 'Use XScale PMU as timer source' CONFIG_XSCALE_PMU_TIMER
869 depends on CPU_XSCALE && !XSCALE_PMU_TIMER
873 source "arch/arm/Kconfig-nommu"
876 config ARM_ERRATA_411920
877 bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
878 depends on CPU_V6 && !SMP
880 Invalidation of the Instruction Cache operation can
881 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
882 It does not affect the MPCore. This option enables the ARM Ltd.
883 recommended workaround.
885 config ARM_ERRATA_430973
886 bool "ARM errata: Stale prediction on replaced interworking branch"
889 This option enables the workaround for the 430973 Cortex-A8
890 (r1p0..r1p2) erratum. If a code sequence containing an ARM/Thumb
891 interworking branch is replaced with another code sequence at the
892 same virtual address, whether due to self-modifying code or virtual
893 to physical address re-mapping, Cortex-A8 does not recover from the
894 stale interworking branch prediction. This results in Cortex-A8
895 executing the new code sequence in the incorrect ARM or Thumb state.
896 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
897 and also flushes the branch target cache at every context switch.
898 Note that setting specific bits in the ACTLR register may not be
899 available in non-secure mode.
901 config ARM_ERRATA_458693
902 bool "ARM errata: Processor deadlock when a false hazard is created"
905 This option enables the workaround for the 458693 Cortex-A8 (r2p0)
906 erratum. For very specific sequences of memory operations, it is
907 possible for a hazard condition intended for a cache line to instead
908 be incorrectly associated with a different cache line. This false
909 hazard might then cause a processor deadlock. The workaround enables
910 the L1 caching of the NEON accesses and disables the PLD instruction
911 in the ACTLR register. Note that setting specific bits in the ACTLR
912 register may not be available in non-secure mode.
914 config ARM_ERRATA_460075
915 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
918 This option enables the workaround for the 460075 Cortex-A8 (r2p0)
919 erratum. Any asynchronous access to the L2 cache may encounter a
920 situation in which recent store transactions to the L2 cache are lost
921 and overwritten with stale memory contents from external memory. The
922 workaround disables the write-allocate mode for the L2 cache via the
923 ACTLR register. Note that setting specific bits in the ACTLR register
924 may not be available in non-secure mode.
926 config ARM_ERRATA_720789
927 bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID"
928 depends on CPU_V7 && SMP
930 This option enables the workaround for the 720789 Cortex-A9 (prior to
931 r2p0) erratum. A faulty ASID can be sent to the other CPUs for the
932 broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS.
933 As a consequence of this erratum, some TLB entries which should be
934 invalidated are not, resulting in an incoherency in the system page
935 tables. The workaround changes the TLB flushing routines to invalidate
936 entries regardless of the ASID.
940 source "arch/arm/common/Kconfig"
942 config FORCE_MAX_ZONEORDER
955 Find out whether you have ISA slots on your motherboard. ISA is the
956 name of a bus system, i.e. the way the CPU talks to the other stuff
957 inside your box. Other bus systems are PCI, EISA, MicroChannel
958 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
959 newer boards don't support it. If you have ISA, say Y, otherwise N.
961 # Select ISA DMA controller support
966 # Select ISA DMA interface
971 bool "PCI support" if ARCH_INTEGRATOR_AP || ARCH_VERSATILE_PB || ARCH_IXP4XX || ARCH_KS8695 || MACH_ARMCORE
973 Find out whether you have a PCI motherboard. PCI is the name of a
974 bus system, i.e. the way the CPU talks to the other stuff inside
975 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
976 VESA. If you have PCI, say Y, otherwise N.
981 # Select the host bridge type
982 config PCI_HOST_VIA82C505
984 depends on PCI && ARCH_SHARK
987 config PCI_HOST_ITE8152
989 depends on PCI && MACH_ARMCORE
993 source "drivers/pci/Kconfig"
995 source "drivers/pcmcia/Kconfig"
999 menu "Kernel Features"
1001 source "kernel/time/Kconfig"
1004 bool "Symmetric Multi-Processing (EXPERIMENTAL)"
1005 depends on EXPERIMENTAL && (REALVIEW_EB_ARM11MP || REALVIEW_EB_A9MP ||\
1006 MACH_REALVIEW_PB11MP || MACH_REALVIEW_PBX || ARCH_OMAP4)
1007 depends on GENERIC_CLOCKEVENTS
1008 select USE_GENERIC_SMP_HELPERS
1009 select HAVE_ARM_SCU if (ARCH_REALVIEW || ARCH_OMAP4)
1011 This enables support for systems with more than one CPU. If you have
1012 a system with only one CPU, like most personal computers, say N. If
1013 you have a system with more than one CPU, say Y.
1015 If you say N here, the kernel will run on single and multiprocessor
1016 machines, but will use only one CPU of a multiprocessor machine. If
1017 you say Y here, the kernel will run on many, but not all, single
1018 processor machines. On a single processor machine, the kernel will
1019 run faster if you say N here.
1021 See also <file:Documentation/i386/IO-APIC.txt>,
1022 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
1023 <http://www.linuxdoc.org/docs.html#howto>.
1025 If you don't know what to do here, say N.
1031 This option enables support for the ARM system coherency unit
1037 This options enables support for the ARM timer and watchdog unit
1040 prompt "Memory split"
1043 Select the desired split between kernel and user memory.
1045 If you are not absolutely sure what you are doing, leave this
1049 bool "3G/1G user/kernel split"
1051 bool "2G/2G user/kernel split"
1053 bool "1G/3G user/kernel split"
1058 default 0x40000000 if VMSPLIT_1G
1059 default 0x80000000 if VMSPLIT_2G
1063 int "Maximum number of CPUs (2-32)"
1069 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
1070 depends on SMP && HOTPLUG && EXPERIMENTAL
1072 Say Y here to experiment with turning CPUs off and on. CPUs
1073 can be controlled through /sys/devices/system/cpu.
1076 bool "Use local timer interrupts"
1077 depends on SMP && (REALVIEW_EB_ARM11MP || MACH_REALVIEW_PB11MP || \
1078 REALVIEW_EB_A9MP || MACH_REALVIEW_PBX || ARCH_OMAP4)
1080 select HAVE_ARM_TWD if (ARCH_REALVIEW || ARCH_OMAP4)
1082 Enable support for local timers on SMP platforms, rather then the
1083 legacy IPI broadcast method. Local timers allows the system
1084 accounting to be spread across the timer interval, preventing a
1085 "thundering herd" at every timer tick.
1087 source kernel/Kconfig.preempt
1091 default 128 if ARCH_L7200
1092 default 200 if ARCH_EBSA110 || ARCH_S3C2410
1093 default OMAP_32K_TIMER_HZ if ARCH_OMAP && OMAP_32K_TIMER
1094 default AT91_TIMER_HZ if ARCH_AT91
1097 config THUMB2_KERNEL
1098 bool "Compile the kernel in Thumb-2 mode"
1099 depends on CPU_V7 && EXPERIMENTAL
1101 select ARM_ASM_UNIFIED
1103 By enabling this option, the kernel will be compiled in
1104 Thumb-2 mode. A compiler/assembler that understand the unified
1105 ARM-Thumb syntax is needed.
1109 config ARM_ASM_UNIFIED
1113 bool "Use the ARM EABI to compile the kernel"
1115 This option allows for the kernel to be compiled using the latest
1116 ARM ABI (aka EABI). This is only useful if you are using a user
1117 space environment that is also compiled with EABI.
1119 Since there are major incompatibilities between the legacy ABI and
1120 EABI, especially with regard to structure member alignment, this
1121 option also changes the kernel syscall calling convention to
1122 disambiguate both ABIs and allow for backward compatibility support
1123 (selected with CONFIG_OABI_COMPAT).
1125 To use this you need GCC version 4.0.0 or later.
1128 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1129 depends on AEABI && EXPERIMENTAL
1132 This option preserves the old syscall interface along with the
1133 new (ARM EABI) one. It also provides a compatibility layer to
1134 intercept syscalls that have structure arguments which layout
1135 in memory differs between the legacy ABI and the new ARM EABI
1136 (only for non "thumb" binaries). This option adds a tiny
1137 overhead to all syscalls and produces a slightly larger kernel.
1138 If you know you'll be using only pure EABI user space then you
1139 can say N here. If this option is not selected and you attempt
1140 to execute a legacy ABI binary then the result will be
1141 UNPREDICTABLE (in fact it can be predicted that it won't work
1142 at all). If in doubt say Y.
1144 config ARCH_HAS_HOLES_MEMORYMODEL
1147 # Discontigmem is deprecated
1148 config ARCH_DISCONTIGMEM_ENABLE
1151 config ARCH_SPARSEMEM_ENABLE
1154 config ARCH_SPARSEMEM_DEFAULT
1155 def_bool ARCH_SPARSEMEM_ENABLE
1157 config ARCH_SELECT_MEMORY_MODEL
1158 def_bool ARCH_DISCONTIGMEM_ENABLE && ARCH_SPARSEMEM_ENABLE
1162 default "4" if ARCH_LH7A40X
1164 depends on NEED_MULTIPLE_NODES
1167 bool "High Memory Support (EXPERIMENTAL)"
1168 depends on MMU && EXPERIMENTAL
1170 The address space of ARM processors is only 4 Gigabytes large
1171 and it has to accommodate user address space, kernel address
1172 space as well as some memory mapped IO. That means that, if you
1173 have a large amount of physical memory and/or IO, not all of the
1174 memory can be "permanently mapped" by the kernel. The physical
1175 memory that is not permanently mapped is called "high memory".
1177 Depending on the selected kernel/user memory split, minimum
1178 vmalloc space and actual amount of RAM, you may not need this
1179 option which should result in a slightly faster kernel.
1184 bool "Allocate 2nd-level pagetables from highmem"
1186 depends on !OUTER_CACHE
1191 bool "Timer and CPU usage LEDs"
1192 depends on ARCH_CDB89712 || ARCH_EBSA110 || \
1193 ARCH_EBSA285 || ARCH_INTEGRATOR || \
1194 ARCH_LUBBOCK || MACH_MAINSTONE || ARCH_NETWINDER || \
1195 ARCH_OMAP || ARCH_P720T || ARCH_PXA_IDP || \
1196 ARCH_SA1100 || ARCH_SHARK || ARCH_VERSATILE || \
1197 ARCH_AT91 || ARCH_DAVINCI || \
1198 ARCH_KS8695 || MACH_RD88F5182 || ARCH_REALVIEW
1200 If you say Y here, the LEDs on your machine will be used
1201 to provide useful information about your current system status.
1203 If you are compiling a kernel for a NetWinder or EBSA-285, you will
1204 be able to select which LEDs are active using the options below. If
1205 you are compiling a kernel for the EBSA-110 or the LART however, the
1206 red LED will simply flash regularly to indicate that the system is
1207 still functional. It is safe to say Y here if you have a CATS
1208 system, but the driver will do nothing.
1211 bool "Timer LED" if (!ARCH_CDB89712 && !ARCH_OMAP) || \
1212 OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1213 || MACH_OMAP_PERSEUS2
1215 depends on !GENERIC_CLOCKEVENTS
1216 default y if ARCH_EBSA110
1218 If you say Y here, one of the system LEDs (the green one on the
1219 NetWinder, the amber one on the EBSA285, or the red one on the LART)
1220 will flash regularly to indicate that the system is still
1221 operational. This is mainly useful to kernel hackers who are
1222 debugging unstable kernels.
1224 The LART uses the same LED for both Timer LED and CPU usage LED
1225 functions. You may choose to use both, but the Timer LED function
1226 will overrule the CPU usage LED.
1229 bool "CPU usage LED" if (!ARCH_CDB89712 && !ARCH_EBSA110 && \
1231 || OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1232 || MACH_OMAP_PERSEUS2
1235 If you say Y here, the red LED will be used to give a good real
1236 time indication of CPU usage, by lighting whenever the idle task
1237 is not currently executing.
1239 The LART uses the same LED for both Timer LED and CPU usage LED
1240 functions. You may choose to use both, but the Timer LED function
1241 will overrule the CPU usage LED.
1243 config ALIGNMENT_TRAP
1245 depends on CPU_CP15_MMU
1246 default y if !ARCH_EBSA110
1248 ARM processors cannot fetch/store information which is not
1249 naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1250 address divisible by 4. On 32-bit ARM processors, these non-aligned
1251 fetch/store instructions will be emulated in software if you say
1252 here, which has a severe performance impact. This is necessary for
1253 correct operation of some network protocols. With an IP-only
1254 configuration it is safe to say N, otherwise say Y.
1256 config UACCESS_WITH_MEMCPY
1257 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user() (EXPERIMENTAL)"
1258 depends on MMU && EXPERIMENTAL
1259 default y if CPU_FEROCEON
1261 Implement faster copy_to_user and clear_user methods for CPU
1262 cores where a 8-word STM instruction give significantly higher
1263 memory write throughput than a sequence of individual 32bit stores.
1265 A possible side effect is a slight increase in scheduling latency
1266 between threads sharing the same address space if they invoke
1267 such copy operations with large buffers.
1269 However, if the CPU data cache is using a write-allocate mode,
1270 this option is unlikely to provide any performance gain.
1276 # Compressed boot loader in ROM. Yes, we really want to ask about
1277 # TEXT and BSS so we preserve their values in the config files.
1278 config ZBOOT_ROM_TEXT
1279 hex "Compressed ROM boot loader base address"
1282 The physical address at which the ROM-able zImage is to be
1283 placed in the target. Platforms which normally make use of
1284 ROM-able zImage formats normally set this to a suitable
1285 value in their defconfig file.
1287 If ZBOOT_ROM is not enabled, this has no effect.
1289 config ZBOOT_ROM_BSS
1290 hex "Compressed ROM boot loader BSS address"
1293 The base address of an area of read/write memory in the target
1294 for the ROM-able zImage which must be available while the
1295 decompressor is running. It must be large enough to hold the
1296 entire decompressed kernel plus an additional 128 KiB.
1297 Platforms which normally make use of ROM-able zImage formats
1298 normally set this to a suitable value in their defconfig file.
1300 If ZBOOT_ROM is not enabled, this has no effect.
1303 bool "Compressed boot loader in ROM/flash"
1304 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1306 Say Y here if you intend to execute your compressed kernel image
1307 (zImage) directly from ROM or flash. If unsure, say N.
1310 string "Default kernel command string"
1313 On some architectures (EBSA110 and CATS), there is currently no way
1314 for the boot loader to pass arguments to the kernel. For these
1315 architectures, you should supply some command-line options at build
1316 time by entering them here. As a minimum, you should specify the
1317 memory size and the root device (e.g., mem=64M root=/dev/nfs).
1320 bool "Kernel Execute-In-Place from ROM"
1321 depends on !ZBOOT_ROM
1323 Execute-In-Place allows the kernel to run from non-volatile storage
1324 directly addressable by the CPU, such as NOR flash. This saves RAM
1325 space since the text section of the kernel is not loaded from flash
1326 to RAM. Read-write sections, such as the data section and stack,
1327 are still copied to RAM. The XIP kernel is not compressed since
1328 it has to run directly from flash, so it will take more space to
1329 store it. The flash address used to link the kernel object files,
1330 and for storing it, is configuration dependent. Therefore, if you
1331 say Y here, you must know the proper physical address where to
1332 store the kernel image depending on your own flash memory usage.
1334 Also note that the make target becomes "make xipImage" rather than
1335 "make zImage" or "make Image". The final kernel binary to put in
1336 ROM memory will be arch/arm/boot/xipImage.
1340 config XIP_PHYS_ADDR
1341 hex "XIP Kernel Physical Location"
1342 depends on XIP_KERNEL
1343 default "0x00080000"
1345 This is the physical address in your flash memory the kernel will
1346 be linked for and stored to. This address is dependent on your
1350 bool "Kexec system call (EXPERIMENTAL)"
1351 depends on EXPERIMENTAL
1353 kexec is a system call that implements the ability to shutdown your
1354 current kernel, and to start another kernel. It is like a reboot
1355 but it is independent of the system firmware. And like a reboot
1356 you can start any kernel with it, not just Linux.
1358 It is an ongoing process to be certain the hardware in a machine
1359 is properly shutdown, so do not be surprised if this code does not
1360 initially work for you. It may help to enable device hotplugging
1364 bool "Export atags in procfs"
1368 Should the atags used to boot the kernel be exported in an "atags"
1369 file in procfs. Useful with kexec.
1373 menu "CPU Power Management"
1377 source "drivers/cpufreq/Kconfig"
1379 config CPU_FREQ_SA1100
1381 depends on CPU_FREQ && (SA1100_H3100 || SA1100_H3600 || SA1100_LART || SA1100_PLEB || SA1100_BADGE4 || SA1100_HACKKIT)
1384 config CPU_FREQ_SA1110
1386 depends on CPU_FREQ && (SA1100_ASSABET || SA1100_CERF || SA1100_PT_SYSTEM3)
1389 config CPU_FREQ_INTEGRATOR
1390 tristate "CPUfreq driver for ARM Integrator CPUs"
1391 depends on ARCH_INTEGRATOR && CPU_FREQ
1394 This enables the CPUfreq driver for ARM Integrator CPUs.
1396 For details, take a look at <file:Documentation/cpu-freq>.
1402 depends on CPU_FREQ && ARCH_PXA && PXA25x
1404 select CPU_FREQ_DEFAULT_GOV_USERSPACE
1406 config CPU_FREQ_S3C64XX
1407 bool "CPUfreq support for Samsung S3C64XX CPUs"
1408 depends on CPU_FREQ && CPU_S3C6410
1413 Internal configuration node for common cpufreq on Samsung SoC
1415 config CPU_FREQ_S3C24XX
1416 bool "CPUfreq driver for Samsung S3C24XX series CPUs"
1417 depends on ARCH_S3C2410 && CPU_FREQ && EXPERIMENTAL
1420 This enables the CPUfreq driver for the Samsung S3C24XX family
1423 For details, take a look at <file:Documentation/cpu-freq>.
1427 config CPU_FREQ_S3C24XX_PLL
1428 bool "Support CPUfreq changing of PLL frequency"
1429 depends on CPU_FREQ_S3C24XX && EXPERIMENTAL
1431 Compile in support for changing the PLL frequency from the
1432 S3C24XX series CPUfreq driver. The PLL takes time to settle
1433 after a frequency change, so by default it is not enabled.
1435 This also means that the PLL tables for the selected CPU(s) will
1436 be built which may increase the size of the kernel image.
1438 config CPU_FREQ_S3C24XX_DEBUG
1439 bool "Debug CPUfreq Samsung driver core"
1440 depends on CPU_FREQ_S3C24XX
1442 Enable s3c_freq_dbg for the Samsung S3C CPUfreq core
1444 config CPU_FREQ_S3C24XX_IODEBUG
1445 bool "Debug CPUfreq Samsung driver IO timing"
1446 depends on CPU_FREQ_S3C24XX
1448 Enable s3c_freq_iodbg for the Samsung S3C CPUfreq core
1450 config CPU_FREQ_S3C24XX_DEBUGFS
1451 bool "Export debugfs for CPUFreq"
1452 depends on CPU_FREQ_S3C24XX && DEBUG_FS
1454 Export status information via debugfs.
1458 source "drivers/cpuidle/Kconfig"
1462 menu "Floating point emulation"
1464 comment "At least one emulation must be selected"
1467 bool "NWFPE math emulation"
1468 depends on !AEABI || OABI_COMPAT
1470 Say Y to include the NWFPE floating point emulator in the kernel.
1471 This is necessary to run most binaries. Linux does not currently
1472 support floating point hardware so you need to say Y here even if
1473 your machine has an FPA or floating point co-processor podule.
1475 You may say N here if you are going to load the Acorn FPEmulator
1476 early in the bootup.
1479 bool "Support extended precision"
1480 depends on FPE_NWFPE
1482 Say Y to include 80-bit support in the kernel floating-point
1483 emulator. Otherwise, only 32 and 64-bit support is compiled in.
1484 Note that gcc does not generate 80-bit operations by default,
1485 so in most cases this option only enlarges the size of the
1486 floating point emulator without any good reason.
1488 You almost surely want to say N here.
1491 bool "FastFPE math emulation (EXPERIMENTAL)"
1492 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3 && EXPERIMENTAL
1494 Say Y here to include the FAST floating point emulator in the kernel.
1495 This is an experimental much faster emulator which now also has full
1496 precision for the mantissa. It does not support any exceptions.
1497 It is very simple, and approximately 3-6 times faster than NWFPE.
1499 It should be sufficient for most programs. It may be not suitable
1500 for scientific calculations, but you have to check this for yourself.
1501 If you do not feel you need a faster FP emulation you should better
1505 bool "VFP-format floating point maths"
1506 depends on CPU_V6 || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
1508 Say Y to include VFP support code in the kernel. This is needed
1509 if your hardware includes a VFP unit.
1511 Please see <file:Documentation/arm/VFP/release-notes.txt> for
1512 release notes and additional status information.
1514 Say N if your target does not have VFP hardware.
1522 bool "Advanced SIMD (NEON) Extension support"
1523 depends on VFPv3 && CPU_V7
1525 Say Y to include support code for NEON, the ARMv7 Advanced SIMD
1530 menu "Userspace binary formats"
1532 source "fs/Kconfig.binfmt"
1535 tristate "RISC OS personality"
1538 Say Y here to include the kernel code necessary if you want to run
1539 Acorn RISC OS/Arthur binaries under Linux. This code is still very
1540 experimental; if this sounds frightening, say N and sleep in peace.
1541 You can also say M here to compile this support as a module (which
1542 will be called arthur).
1546 menu "Power management options"
1548 source "kernel/power/Kconfig"
1550 config ARCH_SUSPEND_POSSIBLE
1555 source "net/Kconfig"
1557 source "drivers/Kconfig"
1561 source "arch/arm/Kconfig.debug"
1563 source "security/Kconfig"
1565 source "crypto/Kconfig"
1567 source "lib/Kconfig"