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
21 select HAVE_KERNEL_GZIP
22 select HAVE_KERNEL_LZO
24 The ARM series is a line of low-power-consumption RISC chip designs
25 licensed by ARM Ltd and targeted at embedded applications and
26 handhelds such as the Compaq IPAQ. ARM-based PCs are no longer
27 manufactured, but legacy ARM-based PC hardware remains popular in
28 Europe. There is an ARM Linux project with a web page at
29 <http://www.arm.linux.org.uk/>.
34 config SYS_SUPPORTS_APM_EMULATION
43 config GENERIC_CLOCKEVENTS
46 config GENERIC_CLOCKEVENTS_BROADCAST
48 depends on GENERIC_CLOCKEVENTS
49 default y if SMP && !LOCAL_TIMERS
53 select GENERIC_ALLOCATOR
61 The Extended Industry Standard Architecture (EISA) bus was
62 developed as an open alternative to the IBM MicroChannel bus.
64 The EISA bus provided some of the features of the IBM MicroChannel
65 bus while maintaining backward compatibility with cards made for
66 the older ISA bus. The EISA bus saw limited use between 1988 and
67 1995 when it was made obsolete by the PCI bus.
69 Say Y here if you are building a kernel for an EISA-based machine.
79 MicroChannel Architecture is found in some IBM PS/2 machines and
80 laptops. It is a bus system similar to PCI or ISA. See
81 <file:Documentation/mca.txt> (and especially the web page given
82 there) before attempting to build an MCA bus kernel.
84 config GENERIC_HARDIRQS
88 config STACKTRACE_SUPPORT
92 config HAVE_LATENCYTOP_SUPPORT
97 config LOCKDEP_SUPPORT
101 config TRACE_IRQFLAGS_SUPPORT
105 config HARDIRQS_SW_RESEND
109 config GENERIC_IRQ_PROBE
113 config GENERIC_LOCKBREAK
116 depends on SMP && PREEMPT
118 config RWSEM_GENERIC_SPINLOCK
122 config RWSEM_XCHGADD_ALGORITHM
125 config ARCH_HAS_ILOG2_U32
128 config ARCH_HAS_ILOG2_U64
131 config ARCH_HAS_CPUFREQ
134 Internal node to signify that the ARCH has CPUFREQ support
135 and that the relevant menu configurations are displayed for
138 config GENERIC_HWEIGHT
142 config GENERIC_CALIBRATE_DELAY
146 config ARCH_MAY_HAVE_PC_FDC
152 config GENERIC_ISA_DMA
161 config GENERIC_HARDIRQS_NO__DO_IRQ
166 config OPROFILE_ARMV6
168 depends on CPU_V6 && !SMP
169 select OPROFILE_ARM11_CORE
171 config OPROFILE_MPCORE
173 depends on CPU_V6 && SMP
174 select OPROFILE_ARM11_CORE
176 config OPROFILE_ARM11_CORE
179 config OPROFILE_ARMV7
181 depends on CPU_V7 && !SMP
188 default 0xffff0000 if MMU || CPU_HIGH_VECTOR
189 default DRAM_BASE if REMAP_VECTORS_TO_RAM
192 The base address of exception vectors.
194 source "init/Kconfig"
196 source "kernel/Kconfig.freezer"
201 bool "MMU-based Paged Memory Management Support"
204 Select if you want MMU-based virtualised addressing space
205 support by paged memory management. If unsure, say 'Y'.
208 prompt "ARM system type"
209 default ARCH_VERSATILE
212 bool "Agilent AAEC-2000 based"
217 This enables support for systems based on the Agilent AAEC-2000
219 config ARCH_INTEGRATOR
220 bool "ARM Ltd. Integrator family"
222 select ARCH_HAS_CPUFREQ
227 Support for ARM's Integrator platform.
230 bool "ARM Ltd. RealView family"
236 select GENERIC_CLOCKEVENTS
237 select ARCH_WANT_OPTIONAL_GPIOLIB
239 This enables support for ARM Ltd RealView boards.
241 config ARCH_VERSATILE
242 bool "ARM Ltd. Versatile family"
249 select GENERIC_CLOCKEVENTS
250 select ARCH_WANT_OPTIONAL_GPIOLIB
252 This enables support for ARM Ltd Versatile board.
257 select ARCH_REQUIRE_GPIOLIB
260 This enables support for systems based on the Atmel AT91RM9200,
261 AT91SAM9 and AT91CAP9 processors.
264 bool "Cirrus Logic CLPS711x/EP721x-based"
267 Support for Cirrus Logic 711x/721x based boards.
270 bool "Cortina Systems Gemini"
273 select ARCH_REQUIRE_GPIOLIB
275 Support for the Cortina Systems Gemini family SoCs
283 This is an evaluation board for the StrongARM processor available
284 from Digital. It has limited hardware on-board, including an
285 Ethernet interface, two PCMCIA sockets, two serial ports and a
296 select ARCH_REQUIRE_GPIOLIB
297 select ARCH_HAS_HOLES_MEMORYMODEL
299 This enables support for the Cirrus EP93xx series of CPUs.
301 config ARCH_FOOTBRIDGE
306 Support for systems based on the DC21285 companion chip
307 ("FootBridge"), such as the Simtec CATS and the Rebel NetWinder.
310 bool "Freescale MXC/iMX-based"
312 select GENERIC_CLOCKEVENTS
315 select ARCH_REQUIRE_GPIOLIB
318 Support for Freescale MXC/iMX-based family of processors
321 bool "Freescale STMP3xxx"
325 select ARCH_REQUIRE_GPIOLIB
327 select GENERIC_CLOCKEVENTS
329 select USB_ARCH_HAS_EHCI
331 Support for systems based on the Freescale 3xxx CPUs.
334 bool "Hilscher NetX based"
337 select GENERIC_CLOCKEVENTS
340 This enables support for systems based on the Hilscher NetX Soc
343 bool "Hynix HMS720x-based"
347 This enables support for systems based on the Hynix HMS720x
350 bool "STMicroelectronics Nomadik"
357 select GENERIC_CLOCKEVENTS
359 select ARCH_REQUIRE_GPIOLIB
361 Support for the Nomadik platform by ST-Ericsson
369 select ARCH_SUPPORTS_MSI
372 Support for Intel's IOP13XX (XScale) family of processors.
381 select ARCH_REQUIRE_GPIOLIB
383 Support for Intel's 80219 and IOP32X (XScale) family of
393 select ARCH_REQUIRE_GPIOLIB
395 Support for Intel's IOP33X (XScale) family of processors.
403 Support for Intel's IXP23xx (XScale) family of processors.
406 bool "IXP2400/2800-based"
411 Support for Intel's IXP2400/2800 (XScale) family of processors.
419 select GENERIC_CLOCKEVENTS
420 select DMABOUNCE if PCI
422 Support for Intel's IXP4XX (XScale) family of processors.
429 Say Y here if you intend to run this kernel on a LinkUp Systems
430 L7200 Software Development Board which uses an ARM720T processor.
431 Information on this board can be obtained at:
433 <http://www.linkupsys.com/>
435 If you have any questions or comments about the Linux kernel port
436 to this board, send e-mail to <sjhill@cotw.com>.
442 select ARCH_REQUIRE_GPIOLIB
444 select GENERIC_CLOCKEVENTS
447 Support for the Marvell Dove SoC 88AP510
450 bool "Marvell Kirkwood"
454 select ARCH_REQUIRE_GPIOLIB
456 select GENERIC_CLOCKEVENTS
459 Support for the following Marvell Kirkwood series SoCs:
460 88F6180, 88F6192 and 88F6281.
463 bool "Marvell Loki (88RC8480)"
466 select GENERIC_CLOCKEVENTS
469 Support for the Marvell Loki (88RC8480) SoC.
472 bool "Marvell MV78xx0"
476 select ARCH_REQUIRE_GPIOLIB
478 select GENERIC_CLOCKEVENTS
481 Support for the following Marvell MV78xx0 series SoCs:
490 select ARCH_REQUIRE_GPIOLIB
492 select GENERIC_CLOCKEVENTS
495 Support for the following Marvell Orion 5x series SoCs:
496 Orion-1 (5181), Orion-VoIP (5181L), Orion-NAS (5182),
497 Orion-2 (5281), Orion-1-90 (6183).
500 bool "Marvell PXA168/910"
503 select ARCH_REQUIRE_GPIOLIB
507 select GENERIC_CLOCKEVENTS
511 Support for Marvell's PXA168/910 processor line.
514 bool "Micrel/Kendin KS8695"
517 select ARCH_REQUIRE_GPIOLIB
519 Support for Micrel/Kendin KS8695 "Centaur" (ARM922T) based
520 System-on-Chip devices.
523 bool "NetSilicon NS9xxx"
527 select GENERIC_CLOCKEVENTS
530 Say Y here if you intend to run this kernel on a NetSilicon NS9xxx
533 <http://www.digi.com/products/microprocessors/index.jsp>
536 bool "Nuvoton W90X900 CPU"
538 select ARCH_REQUIRE_GPIOLIB
543 select GENERIC_CLOCKEVENTS
545 Support for Nuvoton (Winbond logic dept.) ARM9 processor,
546 At present, the w90x900 has been renamed nuc900, regarding
547 the ARM series product line, you can login the following
548 link address to know more.
550 <http://www.nuvoton.com/hq/enu/ProductAndSales/ProductLines/
551 ConsumerElectronicsIC/ARMMicrocontroller/ARMMicrocontroller>
554 bool "Philips Nexperia PNX4008 Mobile"
558 This enables support for Philips PNX4008 mobile platform.
561 bool "PXA2xx/PXA3xx-based"
564 select ARCH_HAS_CPUFREQ
568 select ARCH_REQUIRE_GPIOLIB
570 select GENERIC_CLOCKEVENTS
574 Support for Intel/Marvell's PXA2xx/PXA3xx processor line.
580 select GENERIC_CLOCKEVENTS
582 Support for Qualcomm MSM7K based systems. This runs on the ARM11
583 apps processor of the MSM7K and depends on a shared memory
584 interface to the ARM9 modem processor which runs the baseband stack
585 and controls some vital subsystems (clock and power control, etc).
592 select ARCH_MAY_HAVE_PC_FDC
593 select HAVE_PATA_PLATFORM
596 select ARCH_SPARSEMEM_ENABLE
598 On the Acorn Risc-PC, Linux can support the internal IDE disk and
599 CD-ROM interface, serial and parallel port, and the floppy drive.
605 select ARCH_SPARSEMEM_ENABLE
607 select ARCH_HAS_CPUFREQ
611 select GENERIC_CLOCKEVENTS
614 select ARCH_REQUIRE_GPIOLIB
616 Support for StrongARM 11x0 based boards.
619 bool "Samsung S3C2410, S3C2412, S3C2413, S3C2440, S3C2442, S3C2443"
621 select ARCH_HAS_CPUFREQ
624 Samsung S3C2410X CPU based systems, such as the Simtec Electronics
625 BAST (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or
626 the Samsung SMDK2410 development board (and derivatives).
629 bool "Samsung S3C64XX"
632 select ARCH_HAS_CPUFREQ
634 Samsung S3C64XX series based systems
637 bool "Samsung S5P6440"
642 Samsung S5P6440 CPU based systems
645 bool "Samsung S5PC1XX"
650 Samsung S5PC1XX series based systems
660 Support for the StrongARM based Digital DNARD machine, also known
661 as "Shark" (<http://www.shark-linux.de/shark.html>).
666 select ARCH_DISCONTIGMEM_ENABLE if !LH7A40X_CONTIGMEM
667 select ARCH_SPARSEMEM_ENABLE if !LH7A40X_CONTIGMEM
669 Say Y here for systems based on one of the Sharp LH7A40X
670 System on a Chip processors. These CPUs include an ARM922T
671 core with a wide array of integrated devices for
672 hand-held and low-power applications.
675 bool "ST-Ericsson U300 Series"
682 select GENERIC_CLOCKEVENTS
687 Support for ST-Ericsson U300 series mobile platforms.
693 select GENERIC_CLOCKEVENTS
695 select ARCH_REQUIRE_GPIOLIB
700 select GENERIC_ALLOCATOR
701 select ARCH_HAS_HOLES_MEMORYMODEL
703 Support for TI's DaVinci platform.
709 select ARCH_REQUIRE_GPIOLIB
710 select ARCH_HAS_CPUFREQ
712 select GENERIC_CLOCKEVENTS
714 Support for TI's OMAP platform (OMAP1 and OMAP2).
717 bool "Broadcom BCMRING"
723 select GENERIC_CLOCKEVENTS
724 select ARCH_WANT_OPTIONAL_GPIOLIB
726 Support for Broadcom's BCMRing platform.
729 bool "ST-Ericsson U8500 Series"
733 select GENERIC_CLOCKEVENTS
736 Support for ST-Ericsson's Ux500 architecture
740 source "arch/arm/mach-clps711x/Kconfig"
742 source "arch/arm/mach-ep93xx/Kconfig"
744 source "arch/arm/mach-footbridge/Kconfig"
746 source "arch/arm/mach-gemini/Kconfig"
748 source "arch/arm/mach-integrator/Kconfig"
750 source "arch/arm/mach-iop32x/Kconfig"
752 source "arch/arm/mach-iop33x/Kconfig"
754 source "arch/arm/mach-iop13xx/Kconfig"
756 source "arch/arm/mach-ixp4xx/Kconfig"
758 source "arch/arm/mach-ixp2000/Kconfig"
760 source "arch/arm/mach-ixp23xx/Kconfig"
762 source "arch/arm/mach-loki/Kconfig"
764 source "arch/arm/mach-mv78xx0/Kconfig"
766 source "arch/arm/mach-pxa/Kconfig"
767 source "arch/arm/plat-pxa/Kconfig"
769 source "arch/arm/mach-mmp/Kconfig"
771 source "arch/arm/mach-sa1100/Kconfig"
773 source "arch/arm/plat-omap/Kconfig"
775 source "arch/arm/mach-omap1/Kconfig"
777 source "arch/arm/mach-omap2/Kconfig"
779 source "arch/arm/mach-orion5x/Kconfig"
781 source "arch/arm/mach-kirkwood/Kconfig"
783 source "arch/arm/mach-dove/Kconfig"
785 source "arch/arm/plat-samsung/Kconfig"
786 source "arch/arm/plat-s3c24xx/Kconfig"
787 source "arch/arm/plat-s3c64xx/Kconfig"
788 source "arch/arm/plat-s3c/Kconfig"
789 source "arch/arm/plat-s5p/Kconfig"
790 source "arch/arm/plat-s5pc1xx/Kconfig"
793 source "arch/arm/mach-s3c2400/Kconfig"
794 source "arch/arm/mach-s3c2410/Kconfig"
795 source "arch/arm/mach-s3c2412/Kconfig"
796 source "arch/arm/mach-s3c2440/Kconfig"
797 source "arch/arm/mach-s3c2442/Kconfig"
798 source "arch/arm/mach-s3c2443/Kconfig"
802 source "arch/arm/mach-s3c64xx/Kconfig"
805 source "arch/arm/mach-s5p6440/Kconfig"
807 source "arch/arm/plat-stmp3xxx/Kconfig"
810 source "arch/arm/mach-s5pc100/Kconfig"
813 source "arch/arm/mach-lh7a40x/Kconfig"
815 source "arch/arm/mach-h720x/Kconfig"
817 source "arch/arm/mach-versatile/Kconfig"
819 source "arch/arm/mach-aaec2000/Kconfig"
821 source "arch/arm/mach-realview/Kconfig"
823 source "arch/arm/mach-at91/Kconfig"
825 source "arch/arm/plat-mxc/Kconfig"
827 source "arch/arm/mach-nomadik/Kconfig"
828 source "arch/arm/plat-nomadik/Kconfig"
830 source "arch/arm/mach-netx/Kconfig"
832 source "arch/arm/mach-ns9xxx/Kconfig"
834 source "arch/arm/mach-davinci/Kconfig"
836 source "arch/arm/mach-ks8695/Kconfig"
838 source "arch/arm/mach-msm/Kconfig"
840 source "arch/arm/mach-u300/Kconfig"
842 source "arch/arm/mach-w90x900/Kconfig"
844 source "arch/arm/mach-bcmring/Kconfig"
846 source "arch/arm/mach-ux500/Kconfig"
848 # Definitions to make life easier
854 select GENERIC_CLOCKEVENTS
863 source arch/arm/mm/Kconfig
866 bool "Enable iWMMXt support"
867 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK
868 default y if PXA27x || PXA3xx || ARCH_MMP
870 Enable support for iWMMXt context switching at run time if
871 running on a CPU that supports it.
873 # bool 'Use XScale PMU as timer source' CONFIG_XSCALE_PMU_TIMER
876 depends on CPU_XSCALE && !XSCALE_PMU_TIMER
880 source "arch/arm/Kconfig-nommu"
883 config ARM_ERRATA_411920
884 bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
885 depends on CPU_V6 && !SMP
887 Invalidation of the Instruction Cache operation can
888 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
889 It does not affect the MPCore. This option enables the ARM Ltd.
890 recommended workaround.
892 config ARM_ERRATA_430973
893 bool "ARM errata: Stale prediction on replaced interworking branch"
896 This option enables the workaround for the 430973 Cortex-A8
897 (r1p0..r1p2) erratum. If a code sequence containing an ARM/Thumb
898 interworking branch is replaced with another code sequence at the
899 same virtual address, whether due to self-modifying code or virtual
900 to physical address re-mapping, Cortex-A8 does not recover from the
901 stale interworking branch prediction. This results in Cortex-A8
902 executing the new code sequence in the incorrect ARM or Thumb state.
903 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
904 and also flushes the branch target cache at every context switch.
905 Note that setting specific bits in the ACTLR register may not be
906 available in non-secure mode.
908 config ARM_ERRATA_458693
909 bool "ARM errata: Processor deadlock when a false hazard is created"
912 This option enables the workaround for the 458693 Cortex-A8 (r2p0)
913 erratum. For very specific sequences of memory operations, it is
914 possible for a hazard condition intended for a cache line to instead
915 be incorrectly associated with a different cache line. This false
916 hazard might then cause a processor deadlock. The workaround enables
917 the L1 caching of the NEON accesses and disables the PLD instruction
918 in the ACTLR register. Note that setting specific bits in the ACTLR
919 register may not be available in non-secure mode.
921 config ARM_ERRATA_460075
922 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
925 This option enables the workaround for the 460075 Cortex-A8 (r2p0)
926 erratum. Any asynchronous access to the L2 cache may encounter a
927 situation in which recent store transactions to the L2 cache are lost
928 and overwritten with stale memory contents from external memory. The
929 workaround disables the write-allocate mode for the L2 cache via the
930 ACTLR register. Note that setting specific bits in the ACTLR register
931 may not be available in non-secure mode.
935 source "arch/arm/common/Kconfig"
937 config FORCE_MAX_ZONEORDER
950 Find out whether you have ISA slots on your motherboard. ISA is the
951 name of a bus system, i.e. the way the CPU talks to the other stuff
952 inside your box. Other bus systems are PCI, EISA, MicroChannel
953 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
954 newer boards don't support it. If you have ISA, say Y, otherwise N.
956 # Select ISA DMA controller support
961 # Select ISA DMA interface
966 bool "PCI support" if ARCH_INTEGRATOR_AP || ARCH_VERSATILE_PB || ARCH_IXP4XX || ARCH_KS8695 || MACH_ARMCORE
968 Find out whether you have a PCI motherboard. PCI is the name of a
969 bus system, i.e. the way the CPU talks to the other stuff inside
970 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
971 VESA. If you have PCI, say Y, otherwise N.
976 # Select the host bridge type
977 config PCI_HOST_VIA82C505
979 depends on PCI && ARCH_SHARK
982 config PCI_HOST_ITE8152
984 depends on PCI && MACH_ARMCORE
988 source "drivers/pci/Kconfig"
990 source "drivers/pcmcia/Kconfig"
994 menu "Kernel Features"
996 source "kernel/time/Kconfig"
999 bool "Symmetric Multi-Processing (EXPERIMENTAL)"
1000 depends on EXPERIMENTAL && (REALVIEW_EB_ARM11MP || REALVIEW_EB_A9MP ||\
1001 MACH_REALVIEW_PB11MP || MACH_REALVIEW_PBX || ARCH_OMAP4 || ARCH_U8500)
1002 depends on GENERIC_CLOCKEVENTS
1003 select USE_GENERIC_SMP_HELPERS
1004 select HAVE_ARM_SCU if (ARCH_REALVIEW || ARCH_OMAP4 || ARCH_U8500)
1006 This enables support for systems with more than one CPU. If you have
1007 a system with only one CPU, like most personal computers, say N. If
1008 you have a system with more than one CPU, say Y.
1010 If you say N here, the kernel will run on single and multiprocessor
1011 machines, but will use only one CPU of a multiprocessor machine. If
1012 you say Y here, the kernel will run on many, but not all, single
1013 processor machines. On a single processor machine, the kernel will
1014 run faster if you say N here.
1016 See also <file:Documentation/i386/IO-APIC.txt>,
1017 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
1018 <http://www.linuxdoc.org/docs.html#howto>.
1020 If you don't know what to do here, say N.
1026 This option enables support for the ARM system coherency unit
1032 This options enables support for the ARM timer and watchdog unit
1035 prompt "Memory split"
1038 Select the desired split between kernel and user memory.
1040 If you are not absolutely sure what you are doing, leave this
1044 bool "3G/1G user/kernel split"
1046 bool "2G/2G user/kernel split"
1048 bool "1G/3G user/kernel split"
1053 default 0x40000000 if VMSPLIT_1G
1054 default 0x80000000 if VMSPLIT_2G
1058 int "Maximum number of CPUs (2-32)"
1064 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
1065 depends on SMP && HOTPLUG && EXPERIMENTAL
1067 Say Y here to experiment with turning CPUs off and on. CPUs
1068 can be controlled through /sys/devices/system/cpu.
1071 bool "Use local timer interrupts"
1072 depends on SMP && (REALVIEW_EB_ARM11MP || MACH_REALVIEW_PB11MP || \
1073 REALVIEW_EB_A9MP || MACH_REALVIEW_PBX || ARCH_OMAP4 || ARCH_U8500)
1075 select HAVE_ARM_TWD if (ARCH_REALVIEW || ARCH_OMAP4 || ARCH_U8500)
1077 Enable support for local timers on SMP platforms, rather then the
1078 legacy IPI broadcast method. Local timers allows the system
1079 accounting to be spread across the timer interval, preventing a
1080 "thundering herd" at every timer tick.
1082 source kernel/Kconfig.preempt
1086 default 128 if ARCH_L7200
1087 default 200 if ARCH_EBSA110 || ARCH_S3C2410 || ARCH_S5P6440
1088 default OMAP_32K_TIMER_HZ if ARCH_OMAP && OMAP_32K_TIMER
1089 default AT91_TIMER_HZ if ARCH_AT91
1092 config THUMB2_KERNEL
1093 bool "Compile the kernel in Thumb-2 mode"
1094 depends on CPU_V7 && EXPERIMENTAL
1096 select ARM_ASM_UNIFIED
1098 By enabling this option, the kernel will be compiled in
1099 Thumb-2 mode. A compiler/assembler that understand the unified
1100 ARM-Thumb syntax is needed.
1104 config ARM_ASM_UNIFIED
1108 bool "Use the ARM EABI to compile the kernel"
1110 This option allows for the kernel to be compiled using the latest
1111 ARM ABI (aka EABI). This is only useful if you are using a user
1112 space environment that is also compiled with EABI.
1114 Since there are major incompatibilities between the legacy ABI and
1115 EABI, especially with regard to structure member alignment, this
1116 option also changes the kernel syscall calling convention to
1117 disambiguate both ABIs and allow for backward compatibility support
1118 (selected with CONFIG_OABI_COMPAT).
1120 To use this you need GCC version 4.0.0 or later.
1123 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1124 depends on AEABI && EXPERIMENTAL
1127 This option preserves the old syscall interface along with the
1128 new (ARM EABI) one. It also provides a compatibility layer to
1129 intercept syscalls that have structure arguments which layout
1130 in memory differs between the legacy ABI and the new ARM EABI
1131 (only for non "thumb" binaries). This option adds a tiny
1132 overhead to all syscalls and produces a slightly larger kernel.
1133 If you know you'll be using only pure EABI user space then you
1134 can say N here. If this option is not selected and you attempt
1135 to execute a legacy ABI binary then the result will be
1136 UNPREDICTABLE (in fact it can be predicted that it won't work
1137 at all). If in doubt say Y.
1139 config ARCH_HAS_HOLES_MEMORYMODEL
1142 # Discontigmem is deprecated
1143 config ARCH_DISCONTIGMEM_ENABLE
1146 config ARCH_SPARSEMEM_ENABLE
1149 config ARCH_SPARSEMEM_DEFAULT
1150 def_bool ARCH_SPARSEMEM_ENABLE
1152 config ARCH_SELECT_MEMORY_MODEL
1153 def_bool ARCH_DISCONTIGMEM_ENABLE && ARCH_SPARSEMEM_ENABLE
1157 default "4" if ARCH_LH7A40X
1159 depends on NEED_MULTIPLE_NODES
1162 bool "High Memory Support (EXPERIMENTAL)"
1163 depends on MMU && EXPERIMENTAL
1165 The address space of ARM processors is only 4 Gigabytes large
1166 and it has to accommodate user address space, kernel address
1167 space as well as some memory mapped IO. That means that, if you
1168 have a large amount of physical memory and/or IO, not all of the
1169 memory can be "permanently mapped" by the kernel. The physical
1170 memory that is not permanently mapped is called "high memory".
1172 Depending on the selected kernel/user memory split, minimum
1173 vmalloc space and actual amount of RAM, you may not need this
1174 option which should result in a slightly faster kernel.
1179 bool "Allocate 2nd-level pagetables from highmem"
1181 depends on !OUTER_CACHE
1186 bool "Timer and CPU usage LEDs"
1187 depends on ARCH_CDB89712 || ARCH_EBSA110 || \
1188 ARCH_EBSA285 || ARCH_INTEGRATOR || \
1189 ARCH_LUBBOCK || MACH_MAINSTONE || ARCH_NETWINDER || \
1190 ARCH_OMAP || ARCH_P720T || ARCH_PXA_IDP || \
1191 ARCH_SA1100 || ARCH_SHARK || ARCH_VERSATILE || \
1192 ARCH_AT91 || ARCH_DAVINCI || \
1193 ARCH_KS8695 || MACH_RD88F5182 || ARCH_REALVIEW
1195 If you say Y here, the LEDs on your machine will be used
1196 to provide useful information about your current system status.
1198 If you are compiling a kernel for a NetWinder or EBSA-285, you will
1199 be able to select which LEDs are active using the options below. If
1200 you are compiling a kernel for the EBSA-110 or the LART however, the
1201 red LED will simply flash regularly to indicate that the system is
1202 still functional. It is safe to say Y here if you have a CATS
1203 system, but the driver will do nothing.
1206 bool "Timer LED" if (!ARCH_CDB89712 && !ARCH_OMAP) || \
1207 OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1208 || MACH_OMAP_PERSEUS2
1210 depends on !GENERIC_CLOCKEVENTS
1211 default y if ARCH_EBSA110
1213 If you say Y here, one of the system LEDs (the green one on the
1214 NetWinder, the amber one on the EBSA285, or the red one on the LART)
1215 will flash regularly to indicate that the system is still
1216 operational. This is mainly useful to kernel hackers who are
1217 debugging unstable kernels.
1219 The LART uses the same LED for both Timer LED and CPU usage LED
1220 functions. You may choose to use both, but the Timer LED function
1221 will overrule the CPU usage LED.
1224 bool "CPU usage LED" if (!ARCH_CDB89712 && !ARCH_EBSA110 && \
1226 || OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1227 || MACH_OMAP_PERSEUS2
1230 If you say Y here, the red LED will be used to give a good real
1231 time indication of CPU usage, by lighting whenever the idle task
1232 is not currently executing.
1234 The LART uses the same LED for both Timer LED and CPU usage LED
1235 functions. You may choose to use both, but the Timer LED function
1236 will overrule the CPU usage LED.
1238 config ALIGNMENT_TRAP
1240 depends on CPU_CP15_MMU
1241 default y if !ARCH_EBSA110
1243 ARM processors cannot fetch/store information which is not
1244 naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1245 address divisible by 4. On 32-bit ARM processors, these non-aligned
1246 fetch/store instructions will be emulated in software if you say
1247 here, which has a severe performance impact. This is necessary for
1248 correct operation of some network protocols. With an IP-only
1249 configuration it is safe to say N, otherwise say Y.
1251 config UACCESS_WITH_MEMCPY
1252 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user() (EXPERIMENTAL)"
1253 depends on MMU && EXPERIMENTAL
1254 default y if CPU_FEROCEON
1256 Implement faster copy_to_user and clear_user methods for CPU
1257 cores where a 8-word STM instruction give significantly higher
1258 memory write throughput than a sequence of individual 32bit stores.
1260 A possible side effect is a slight increase in scheduling latency
1261 between threads sharing the same address space if they invoke
1262 such copy operations with large buffers.
1264 However, if the CPU data cache is using a write-allocate mode,
1265 this option is unlikely to provide any performance gain.
1271 # Compressed boot loader in ROM. Yes, we really want to ask about
1272 # TEXT and BSS so we preserve their values in the config files.
1273 config ZBOOT_ROM_TEXT
1274 hex "Compressed ROM boot loader base address"
1277 The physical address at which the ROM-able zImage is to be
1278 placed in the target. Platforms which normally make use of
1279 ROM-able zImage formats normally set this to a suitable
1280 value in their defconfig file.
1282 If ZBOOT_ROM is not enabled, this has no effect.
1284 config ZBOOT_ROM_BSS
1285 hex "Compressed ROM boot loader BSS address"
1288 The base address of an area of read/write memory in the target
1289 for the ROM-able zImage which must be available while the
1290 decompressor is running. It must be large enough to hold the
1291 entire decompressed kernel plus an additional 128 KiB.
1292 Platforms which normally make use of ROM-able zImage formats
1293 normally set this to a suitable value in their defconfig file.
1295 If ZBOOT_ROM is not enabled, this has no effect.
1298 bool "Compressed boot loader in ROM/flash"
1299 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1301 Say Y here if you intend to execute your compressed kernel image
1302 (zImage) directly from ROM or flash. If unsure, say N.
1305 string "Default kernel command string"
1308 On some architectures (EBSA110 and CATS), there is currently no way
1309 for the boot loader to pass arguments to the kernel. For these
1310 architectures, you should supply some command-line options at build
1311 time by entering them here. As a minimum, you should specify the
1312 memory size and the root device (e.g., mem=64M root=/dev/nfs).
1315 bool "Kernel Execute-In-Place from ROM"
1316 depends on !ZBOOT_ROM
1318 Execute-In-Place allows the kernel to run from non-volatile storage
1319 directly addressable by the CPU, such as NOR flash. This saves RAM
1320 space since the text section of the kernel is not loaded from flash
1321 to RAM. Read-write sections, such as the data section and stack,
1322 are still copied to RAM. The XIP kernel is not compressed since
1323 it has to run directly from flash, so it will take more space to
1324 store it. The flash address used to link the kernel object files,
1325 and for storing it, is configuration dependent. Therefore, if you
1326 say Y here, you must know the proper physical address where to
1327 store the kernel image depending on your own flash memory usage.
1329 Also note that the make target becomes "make xipImage" rather than
1330 "make zImage" or "make Image". The final kernel binary to put in
1331 ROM memory will be arch/arm/boot/xipImage.
1335 config XIP_PHYS_ADDR
1336 hex "XIP Kernel Physical Location"
1337 depends on XIP_KERNEL
1338 default "0x00080000"
1340 This is the physical address in your flash memory the kernel will
1341 be linked for and stored to. This address is dependent on your
1345 bool "Kexec system call (EXPERIMENTAL)"
1346 depends on EXPERIMENTAL
1348 kexec is a system call that implements the ability to shutdown your
1349 current kernel, and to start another kernel. It is like a reboot
1350 but it is independent of the system firmware. And like a reboot
1351 you can start any kernel with it, not just Linux.
1353 It is an ongoing process to be certain the hardware in a machine
1354 is properly shutdown, so do not be surprised if this code does not
1355 initially work for you. It may help to enable device hotplugging
1359 bool "Export atags in procfs"
1363 Should the atags used to boot the kernel be exported in an "atags"
1364 file in procfs. Useful with kexec.
1368 menu "CPU Power Management"
1372 source "drivers/cpufreq/Kconfig"
1374 config CPU_FREQ_SA1100
1377 config CPU_FREQ_SA1110
1380 config CPU_FREQ_INTEGRATOR
1381 tristate "CPUfreq driver for ARM Integrator CPUs"
1382 depends on ARCH_INTEGRATOR && CPU_FREQ
1385 This enables the CPUfreq driver for ARM Integrator CPUs.
1387 For details, take a look at <file:Documentation/cpu-freq>.
1393 depends on CPU_FREQ && ARCH_PXA && PXA25x
1395 select CPU_FREQ_DEFAULT_GOV_USERSPACE
1397 config CPU_FREQ_S3C64XX
1398 bool "CPUfreq support for Samsung S3C64XX CPUs"
1399 depends on CPU_FREQ && CPU_S3C6410
1404 Internal configuration node for common cpufreq on Samsung SoC
1406 config CPU_FREQ_S3C24XX
1407 bool "CPUfreq driver for Samsung S3C24XX series CPUs"
1408 depends on ARCH_S3C2410 && CPU_FREQ && EXPERIMENTAL
1411 This enables the CPUfreq driver for the Samsung S3C24XX family
1414 For details, take a look at <file:Documentation/cpu-freq>.
1418 config CPU_FREQ_S3C24XX_PLL
1419 bool "Support CPUfreq changing of PLL frequency"
1420 depends on CPU_FREQ_S3C24XX && EXPERIMENTAL
1422 Compile in support for changing the PLL frequency from the
1423 S3C24XX series CPUfreq driver. The PLL takes time to settle
1424 after a frequency change, so by default it is not enabled.
1426 This also means that the PLL tables for the selected CPU(s) will
1427 be built which may increase the size of the kernel image.
1429 config CPU_FREQ_S3C24XX_DEBUG
1430 bool "Debug CPUfreq Samsung driver core"
1431 depends on CPU_FREQ_S3C24XX
1433 Enable s3c_freq_dbg for the Samsung S3C CPUfreq core
1435 config CPU_FREQ_S3C24XX_IODEBUG
1436 bool "Debug CPUfreq Samsung driver IO timing"
1437 depends on CPU_FREQ_S3C24XX
1439 Enable s3c_freq_iodbg for the Samsung S3C CPUfreq core
1441 config CPU_FREQ_S3C24XX_DEBUGFS
1442 bool "Export debugfs for CPUFreq"
1443 depends on CPU_FREQ_S3C24XX && DEBUG_FS
1445 Export status information via debugfs.
1449 source "drivers/cpuidle/Kconfig"
1453 menu "Floating point emulation"
1455 comment "At least one emulation must be selected"
1458 bool "NWFPE math emulation"
1459 depends on !AEABI || OABI_COMPAT
1461 Say Y to include the NWFPE floating point emulator in the kernel.
1462 This is necessary to run most binaries. Linux does not currently
1463 support floating point hardware so you need to say Y here even if
1464 your machine has an FPA or floating point co-processor podule.
1466 You may say N here if you are going to load the Acorn FPEmulator
1467 early in the bootup.
1470 bool "Support extended precision"
1471 depends on FPE_NWFPE
1473 Say Y to include 80-bit support in the kernel floating-point
1474 emulator. Otherwise, only 32 and 64-bit support is compiled in.
1475 Note that gcc does not generate 80-bit operations by default,
1476 so in most cases this option only enlarges the size of the
1477 floating point emulator without any good reason.
1479 You almost surely want to say N here.
1482 bool "FastFPE math emulation (EXPERIMENTAL)"
1483 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3 && EXPERIMENTAL
1485 Say Y here to include the FAST floating point emulator in the kernel.
1486 This is an experimental much faster emulator which now also has full
1487 precision for the mantissa. It does not support any exceptions.
1488 It is very simple, and approximately 3-6 times faster than NWFPE.
1490 It should be sufficient for most programs. It may be not suitable
1491 for scientific calculations, but you have to check this for yourself.
1492 If you do not feel you need a faster FP emulation you should better
1496 bool "VFP-format floating point maths"
1497 depends on CPU_V6 || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
1499 Say Y to include VFP support code in the kernel. This is needed
1500 if your hardware includes a VFP unit.
1502 Please see <file:Documentation/arm/VFP/release-notes.txt> for
1503 release notes and additional status information.
1505 Say N if your target does not have VFP hardware.
1513 bool "Advanced SIMD (NEON) Extension support"
1514 depends on VFPv3 && CPU_V7
1516 Say Y to include support code for NEON, the ARMv7 Advanced SIMD
1521 menu "Userspace binary formats"
1523 source "fs/Kconfig.binfmt"
1526 tristate "RISC OS personality"
1529 Say Y here to include the kernel code necessary if you want to run
1530 Acorn RISC OS/Arthur binaries under Linux. This code is still very
1531 experimental; if this sounds frightening, say N and sleep in peace.
1532 You can also say M here to compile this support as a module (which
1533 will be called arthur).
1537 menu "Power management options"
1539 source "kernel/power/Kconfig"
1541 config ARCH_SUSPEND_POSSIBLE
1546 source "net/Kconfig"
1548 source "drivers/Kconfig"
1552 source "arch/arm/Kconfig.debug"
1554 source "security/Kconfig"
1556 source "crypto/Kconfig"
1558 source "lib/Kconfig"