2 # For a description of the syntax of this configuration file,
3 # see Documentation/kbuild/kconfig-language.txt.
6 mainmenu "Linux Kernel Configuration"
14 select SYS_SUPPORTS_APM_EMULATION
17 select HAVE_KPROBES if (!XIP_KERNEL)
18 select HAVE_KRETPROBES if (HAVE_KPROBES)
19 select HAVE_FUNCTION_TRACER if (!XIP_KERNEL)
20 select HAVE_GENERIC_DMA_COHERENT
22 The ARM series is a line of low-power-consumption RISC chip designs
23 licensed by ARM Ltd and targeted at embedded applications and
24 handhelds such as the Compaq IPAQ. ARM-based PCs are no longer
25 manufactured, but legacy ARM-based PC hardware remains popular in
26 Europe. There is an ARM Linux project with a web page at
27 <http://www.arm.linux.org.uk/>.
32 config SYS_SUPPORTS_APM_EMULATION
41 config GENERIC_CLOCKEVENTS
44 config GENERIC_CLOCKEVENTS_BROADCAST
46 depends on GENERIC_CLOCKEVENTS
47 default y if SMP && !LOCAL_TIMERS
51 select GENERIC_ALLOCATOR
59 The Extended Industry Standard Architecture (EISA) bus was
60 developed as an open alternative to the IBM MicroChannel bus.
62 The EISA bus provided some of the features of the IBM MicroChannel
63 bus while maintaining backward compatibility with cards made for
64 the older ISA bus. The EISA bus saw limited use between 1988 and
65 1995 when it was made obsolete by the PCI bus.
67 Say Y here if you are building a kernel for an EISA-based machine.
77 MicroChannel Architecture is found in some IBM PS/2 machines and
78 laptops. It is a bus system similar to PCI or ISA. See
79 <file:Documentation/mca.txt> (and especially the web page given
80 there) before attempting to build an MCA bus kernel.
82 config GENERIC_HARDIRQS
86 config STACKTRACE_SUPPORT
90 config HAVE_LATENCYTOP_SUPPORT
95 config LOCKDEP_SUPPORT
99 config TRACE_IRQFLAGS_SUPPORT
103 config HARDIRQS_SW_RESEND
107 config GENERIC_IRQ_PROBE
111 config GENERIC_LOCKBREAK
114 depends on SMP && PREEMPT
116 config RWSEM_GENERIC_SPINLOCK
120 config RWSEM_XCHGADD_ALGORITHM
123 config ARCH_HAS_ILOG2_U32
126 config ARCH_HAS_ILOG2_U64
129 config ARCH_HAS_CPUFREQ
132 Internal node to signify that the ARCH has CPUFREQ support
133 and that the relevant menu configurations are displayed for
136 config GENERIC_HWEIGHT
140 config GENERIC_CALIBRATE_DELAY
144 config ARCH_MAY_HAVE_PC_FDC
150 config GENERIC_ISA_DMA
159 config GENERIC_HARDIRQS_NO__DO_IRQ
164 config OPROFILE_ARMV6
166 depends on CPU_V6 && !SMP
167 select OPROFILE_ARM11_CORE
169 config OPROFILE_MPCORE
171 depends on CPU_V6 && SMP
172 select OPROFILE_ARM11_CORE
174 config OPROFILE_ARM11_CORE
177 config OPROFILE_ARMV7
179 depends on CPU_V7 && !SMP
186 default 0xffff0000 if MMU || CPU_HIGH_VECTOR
187 default DRAM_BASE if REMAP_VECTORS_TO_RAM
190 The base address of exception vectors.
192 source "init/Kconfig"
194 source "kernel/Kconfig.freezer"
199 bool "MMU-based Paged Memory Management Support"
202 Select if you want MMU-based virtualised addressing space
203 support by paged memory management. If unsure, say 'Y'.
206 prompt "ARM system type"
207 default ARCH_VERSATILE
210 bool "Agilent AAEC-2000 based"
215 This enables support for systems based on the Agilent AAEC-2000
217 config ARCH_INTEGRATOR
218 bool "ARM Ltd. Integrator family"
220 select ARCH_HAS_CPUFREQ
225 Support for ARM's Integrator platform.
228 bool "ARM Ltd. RealView family"
234 select GENERIC_CLOCKEVENTS
235 select ARCH_WANT_OPTIONAL_GPIOLIB
237 This enables support for ARM Ltd RealView boards.
239 config ARCH_VERSATILE
240 bool "ARM Ltd. Versatile family"
247 select GENERIC_CLOCKEVENTS
248 select ARCH_WANT_OPTIONAL_GPIOLIB
250 This enables support for ARM Ltd Versatile board.
255 select ARCH_REQUIRE_GPIOLIB
258 This enables support for systems based on the Atmel AT91RM9200,
259 AT91SAM9 and AT91CAP9 processors.
262 bool "Cirrus Logic CLPS711x/EP721x-based"
265 Support for Cirrus Logic 711x/721x based boards.
268 bool "Cortina Systems Gemini"
271 select ARCH_REQUIRE_GPIOLIB
273 Support for the Cortina Systems Gemini family SoCs
281 This is an evaluation board for the StrongARM processor available
282 from Digital. It has limited hardware on-board, including an
283 Ethernet interface, two PCMCIA sockets, two serial ports and a
294 select ARCH_REQUIRE_GPIOLIB
295 select ARCH_HAS_HOLES_MEMORYMODEL
297 This enables support for the Cirrus EP93xx series of CPUs.
299 config ARCH_FOOTBRIDGE
304 Support for systems based on the DC21285 companion chip
305 ("FootBridge"), such as the Simtec CATS and the Rebel NetWinder.
308 bool "Freescale MXC/iMX-based"
310 select GENERIC_CLOCKEVENTS
313 select ARCH_REQUIRE_GPIOLIB
316 Support for Freescale MXC/iMX-based family of processors
319 bool "Freescale STMP3xxx"
323 select ARCH_REQUIRE_GPIOLIB
325 select GENERIC_CLOCKEVENTS
327 select USB_ARCH_HAS_EHCI
329 Support for systems based on the Freescale 3xxx CPUs.
332 bool "Hilscher NetX based"
335 select GENERIC_CLOCKEVENTS
338 This enables support for systems based on the Hilscher NetX Soc
341 bool "Hynix HMS720x-based"
345 This enables support for systems based on the Hynix HMS720x
348 bool "STMicroelectronics Nomadik"
355 select GENERIC_CLOCKEVENTS
357 select ARCH_REQUIRE_GPIOLIB
359 Support for the Nomadik platform by ST-Ericsson
367 select ARCH_SUPPORTS_MSI
370 Support for Intel's IOP13XX (XScale) family of processors.
379 select ARCH_REQUIRE_GPIOLIB
381 Support for Intel's 80219 and IOP32X (XScale) family of
391 select ARCH_REQUIRE_GPIOLIB
393 Support for Intel's IOP33X (XScale) family of processors.
401 Support for Intel's IXP23xx (XScale) family of processors.
404 bool "IXP2400/2800-based"
409 Support for Intel's IXP2400/2800 (XScale) family of processors.
417 select GENERIC_CLOCKEVENTS
418 select DMABOUNCE if PCI
420 Support for Intel's IXP4XX (XScale) family of processors.
427 Say Y here if you intend to run this kernel on a LinkUp Systems
428 L7200 Software Development Board which uses an ARM720T processor.
429 Information on this board can be obtained at:
431 <http://www.linkupsys.com/>
433 If you have any questions or comments about the Linux kernel port
434 to this board, send e-mail to <sjhill@cotw.com>.
437 bool "Marvell Kirkwood"
441 select ARCH_REQUIRE_GPIOLIB
443 select GENERIC_CLOCKEVENTS
446 Support for the following Marvell Kirkwood series SoCs:
447 88F6180, 88F6192 and 88F6281.
450 bool "Marvell Loki (88RC8480)"
453 select GENERIC_CLOCKEVENTS
456 Support for the Marvell Loki (88RC8480) SoC.
459 bool "Marvell MV78xx0"
463 select ARCH_REQUIRE_GPIOLIB
465 select GENERIC_CLOCKEVENTS
468 Support for the following Marvell MV78xx0 series SoCs:
477 select ARCH_REQUIRE_GPIOLIB
479 select GENERIC_CLOCKEVENTS
482 Support for the following Marvell Orion 5x series SoCs:
483 Orion-1 (5181), Orion-VoIP (5181L), Orion-NAS (5182),
484 Orion-2 (5281), Orion-1-90 (6183).
487 bool "Marvell PXA168/910"
490 select ARCH_REQUIRE_GPIOLIB
494 select GENERIC_CLOCKEVENTS
498 Support for Marvell's PXA168/910 processor line.
501 bool "Micrel/Kendin KS8695"
504 select ARCH_REQUIRE_GPIOLIB
506 Support for Micrel/Kendin KS8695 "Centaur" (ARM922T) based
507 System-on-Chip devices.
510 bool "NetSilicon NS9xxx"
514 select GENERIC_CLOCKEVENTS
517 Say Y here if you intend to run this kernel on a NetSilicon NS9xxx
520 <http://www.digi.com/products/microprocessors/index.jsp>
523 bool "Nuvoton W90X900 CPU"
525 select ARCH_REQUIRE_GPIOLIB
530 select GENERIC_CLOCKEVENTS
532 Support for Nuvoton (Winbond logic dept.) ARM9 processor,
533 At present, the w90x900 has been renamed nuc900, regarding
534 the ARM series product line, you can login the following
535 link address to know more.
537 <http://www.nuvoton.com/hq/enu/ProductAndSales/ProductLines/
538 ConsumerElectronicsIC/ARMMicrocontroller/ARMMicrocontroller>
541 bool "Philips Nexperia PNX4008 Mobile"
545 This enables support for Philips PNX4008 mobile platform.
548 bool "PXA2xx/PXA3xx-based"
551 select ARCH_HAS_CPUFREQ
555 select ARCH_REQUIRE_GPIOLIB
557 select GENERIC_CLOCKEVENTS
561 Support for Intel/Marvell's PXA2xx/PXA3xx processor line.
567 select GENERIC_CLOCKEVENTS
569 Support for Qualcomm MSM7K based systems. This runs on the ARM11
570 apps processor of the MSM7K and depends on a shared memory
571 interface to the ARM9 modem processor which runs the baseband stack
572 and controls some vital subsystems (clock and power control, etc).
579 select ARCH_MAY_HAVE_PC_FDC
580 select HAVE_PATA_PLATFORM
583 select ARCH_SPARSEMEM_ENABLE
585 On the Acorn Risc-PC, Linux can support the internal IDE disk and
586 CD-ROM interface, serial and parallel port, and the floppy drive.
592 select ARCH_SPARSEMEM_ENABLE
594 select ARCH_HAS_CPUFREQ
597 select GENERIC_CLOCKEVENTS
600 select ARCH_REQUIRE_GPIOLIB
602 Support for StrongARM 11x0 based boards.
605 bool "Samsung S3C2410, S3C2412, S3C2413, S3C2440, S3C2442, S3C2443"
607 select ARCH_HAS_CPUFREQ
610 Samsung S3C2410X CPU based systems, such as the Simtec Electronics
611 BAST (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or
612 the Samsung SMDK2410 development board (and derivatives).
615 bool "Samsung S3C64XX"
618 select ARCH_HAS_CPUFREQ
620 Samsung S3C64XX series based systems
623 bool "Samsung S5PC1XX"
628 Samsung S5PC1XX series based systems
638 Support for the StrongARM based Digital DNARD machine, also known
639 as "Shark" (<http://www.shark-linux.de/shark.html>).
644 select ARCH_DISCONTIGMEM_ENABLE if !LH7A40X_CONTIGMEM
645 select ARCH_SPARSEMEM_ENABLE if !LH7A40X_CONTIGMEM
647 Say Y here for systems based on one of the Sharp LH7A40X
648 System on a Chip processors. These CPUs include an ARM922T
649 core with a wide array of integrated devices for
650 hand-held and low-power applications.
653 bool "ST-Ericsson U300 Series"
660 select GENERIC_CLOCKEVENTS
665 Support for ST-Ericsson U300 series mobile platforms.
671 select GENERIC_CLOCKEVENTS
673 select ARCH_REQUIRE_GPIOLIB
678 select GENERIC_ALLOCATOR
680 Support for TI's DaVinci platform.
686 select ARCH_REQUIRE_GPIOLIB
687 select ARCH_HAS_CPUFREQ
689 select GENERIC_CLOCKEVENTS
691 Support for TI's OMAP platform (OMAP1 and OMAP2).
694 bool "Broadcom BCMRING"
700 select GENERIC_CLOCKEVENTS
701 select ARCH_WANT_OPTIONAL_GPIOLIB
703 Support for Broadcom's BCMRing platform.
706 bool "Rockchip soc rk2818"
712 select ARCH_HAS_CPUFREQ
714 select GENERIC_CLOCKEVENTS
715 select ARCH_REQUIRE_GPIOLIB
717 Support for Rockchip RK2818 soc.
720 bool "Rockchip Soc Rk29"
724 select GENERIC_CLOCKEVENTS
727 Support for Rockchip RK29 soc.
731 source "arch/arm/mach-clps711x/Kconfig"
733 source "arch/arm/mach-ep93xx/Kconfig"
735 source "arch/arm/mach-footbridge/Kconfig"
737 source "arch/arm/mach-gemini/Kconfig"
739 source "arch/arm/mach-integrator/Kconfig"
741 source "arch/arm/mach-iop32x/Kconfig"
743 source "arch/arm/mach-iop33x/Kconfig"
745 source "arch/arm/mach-iop13xx/Kconfig"
747 source "arch/arm/mach-ixp4xx/Kconfig"
749 source "arch/arm/mach-ixp2000/Kconfig"
751 source "arch/arm/mach-ixp23xx/Kconfig"
753 source "arch/arm/mach-loki/Kconfig"
755 source "arch/arm/mach-mv78xx0/Kconfig"
757 source "arch/arm/mach-pxa/Kconfig"
758 source "arch/arm/plat-pxa/Kconfig"
760 source "arch/arm/mach-mmp/Kconfig"
762 source "arch/arm/mach-sa1100/Kconfig"
764 source "arch/arm/plat-omap/Kconfig"
766 source "arch/arm/mach-omap1/Kconfig"
768 source "arch/arm/mach-omap2/Kconfig"
770 source "arch/arm/mach-orion5x/Kconfig"
772 source "arch/arm/mach-kirkwood/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"
815 source "arch/arm/mach-netx/Kconfig"
817 source "arch/arm/mach-ns9xxx/Kconfig"
819 source "arch/arm/mach-davinci/Kconfig"
821 source "arch/arm/mach-ks8695/Kconfig"
823 source "arch/arm/mach-msm/Kconfig"
825 source "arch/arm/mach-u300/Kconfig"
827 source "arch/arm/mach-w90x900/Kconfig"
829 source "arch/arm/mach-bcmring/Kconfig"
831 source "arch/arm/mach-rk2818/Kconfig"
833 source "arch/arm/mach-rk29/Kconfig"
835 # Definitions to make life easier
848 source arch/arm/mm/Kconfig
851 bool "Enable iWMMXt support"
852 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK
853 default y if PXA27x || PXA3xx || ARCH_MMP
855 Enable support for iWMMXt context switching at run time if
856 running on a CPU that supports it.
858 # bool 'Use XScale PMU as timer source' CONFIG_XSCALE_PMU_TIMER
861 depends on CPU_XSCALE && !XSCALE_PMU_TIMER
865 source "arch/arm/Kconfig-nommu"
868 config ARM_ERRATA_411920
869 bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
870 depends on CPU_V6 && !SMP
872 Invalidation of the Instruction Cache operation can
873 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
874 It does not affect the MPCore. This option enables the ARM Ltd.
875 recommended workaround.
877 config ARM_ERRATA_430973
878 bool "ARM errata: Stale prediction on replaced interworking branch"
881 This option enables the workaround for the 430973 Cortex-A8
882 (r1p0..r1p2) erratum. If a code sequence containing an ARM/Thumb
883 interworking branch is replaced with another code sequence at the
884 same virtual address, whether due to self-modifying code or virtual
885 to physical address re-mapping, Cortex-A8 does not recover from the
886 stale interworking branch prediction. This results in Cortex-A8
887 executing the new code sequence in the incorrect ARM or Thumb state.
888 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
889 and also flushes the branch target cache at every context switch.
890 Note that setting specific bits in the ACTLR register may not be
891 available in non-secure mode.
893 config ARM_ERRATA_458693
894 bool "ARM errata: Processor deadlock when a false hazard is created"
897 This option enables the workaround for the 458693 Cortex-A8 (r2p0)
898 erratum. For very specific sequences of memory operations, it is
899 possible for a hazard condition intended for a cache line to instead
900 be incorrectly associated with a different cache line. This false
901 hazard might then cause a processor deadlock. The workaround enables
902 the L1 caching of the NEON accesses and disables the PLD instruction
903 in the ACTLR register. Note that setting specific bits in the ACTLR
904 register may not be available in non-secure mode.
906 config ARM_ERRATA_460075
907 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
910 This option enables the workaround for the 460075 Cortex-A8 (r2p0)
911 erratum. Any asynchronous access to the L2 cache may encounter a
912 situation in which recent store transactions to the L2 cache are lost
913 and overwritten with stale memory contents from external memory. The
914 workaround disables the write-allocate mode for the L2 cache via the
915 ACTLR register. Note that setting specific bits in the ACTLR register
916 may not be available in non-secure mode.
920 source "arch/arm/common/Kconfig"
922 config FORCE_MAX_ZONEORDER
935 Find out whether you have ISA slots on your motherboard. ISA is the
936 name of a bus system, i.e. the way the CPU talks to the other stuff
937 inside your box. Other bus systems are PCI, EISA, MicroChannel
938 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
939 newer boards don't support it. If you have ISA, say Y, otherwise N.
941 # Select ISA DMA controller support
946 # Select ISA DMA interface
951 bool "PCI support" if ARCH_INTEGRATOR_AP || ARCH_VERSATILE_PB || ARCH_IXP4XX || ARCH_KS8695 || MACH_ARMCORE
953 Find out whether you have a PCI motherboard. PCI is the name of a
954 bus system, i.e. the way the CPU talks to the other stuff inside
955 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
956 VESA. If you have PCI, say Y, otherwise N.
961 # Select the host bridge type
962 config PCI_HOST_VIA82C505
964 depends on PCI && ARCH_SHARK
967 config PCI_HOST_ITE8152
969 depends on PCI && MACH_ARMCORE
973 source "drivers/pci/Kconfig"
975 source "drivers/pcmcia/Kconfig"
979 menu "Kernel Features"
981 source "kernel/time/Kconfig"
984 bool "Symmetric Multi-Processing (EXPERIMENTAL)"
985 depends on EXPERIMENTAL && (REALVIEW_EB_ARM11MP || REALVIEW_EB_A9MP ||\
986 MACH_REALVIEW_PB11MP || MACH_REALVIEW_PBX || ARCH_OMAP4)
987 depends on GENERIC_CLOCKEVENTS
988 select USE_GENERIC_SMP_HELPERS
989 select HAVE_ARM_SCU if (ARCH_REALVIEW || ARCH_OMAP4)
991 This enables support for systems with more than one CPU. If you have
992 a system with only one CPU, like most personal computers, say N. If
993 you have a system with more than one CPU, say Y.
995 If you say N here, the kernel will run on single and multiprocessor
996 machines, but will use only one CPU of a multiprocessor machine. If
997 you say Y here, the kernel will run on many, but not all, single
998 processor machines. On a single processor machine, the kernel will
999 run faster if you say N here.
1001 See also <file:Documentation/i386/IO-APIC.txt>,
1002 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
1003 <http://www.linuxdoc.org/docs.html#howto>.
1005 If you don't know what to do here, say N.
1011 This option enables support for the ARM system coherency unit
1017 This options enables support for the ARM timer and watchdog unit
1020 prompt "Memory split"
1023 Select the desired split between kernel and user memory.
1025 If you are not absolutely sure what you are doing, leave this
1029 bool "3G/1G user/kernel split"
1031 bool "2G/2G user/kernel split"
1033 bool "1G/3G user/kernel split"
1038 default 0x40000000 if VMSPLIT_1G
1039 default 0x80000000 if VMSPLIT_2G
1043 int "Maximum number of CPUs (2-32)"
1049 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
1050 depends on SMP && HOTPLUG && EXPERIMENTAL
1052 Say Y here to experiment with turning CPUs off and on. CPUs
1053 can be controlled through /sys/devices/system/cpu.
1056 bool "Use local timer interrupts"
1057 depends on SMP && (REALVIEW_EB_ARM11MP || MACH_REALVIEW_PB11MP || \
1058 REALVIEW_EB_A9MP || MACH_REALVIEW_PBX || ARCH_OMAP4)
1060 select HAVE_ARM_TWD if (ARCH_REALVIEW || ARCH_OMAP4)
1062 Enable support for local timers on SMP platforms, rather then the
1063 legacy IPI broadcast method. Local timers allows the system
1064 accounting to be spread across the timer interval, preventing a
1065 "thundering herd" at every timer tick.
1067 source kernel/Kconfig.preempt
1071 default 128 if ARCH_L7200
1072 default 200 if ARCH_EBSA110 || ARCH_S3C2410
1073 default OMAP_32K_TIMER_HZ if ARCH_OMAP && OMAP_32K_TIMER
1074 default AT91_TIMER_HZ if ARCH_AT91
1077 config THUMB2_KERNEL
1078 bool "Compile the kernel in Thumb-2 mode"
1079 depends on CPU_V7 && EXPERIMENTAL
1081 select ARM_ASM_UNIFIED
1083 By enabling this option, the kernel will be compiled in
1084 Thumb-2 mode. A compiler/assembler that understand the unified
1085 ARM-Thumb syntax is needed.
1089 config ARM_ASM_UNIFIED
1093 bool "Use the ARM EABI to compile the kernel"
1095 This option allows for the kernel to be compiled using the latest
1096 ARM ABI (aka EABI). This is only useful if you are using a user
1097 space environment that is also compiled with EABI.
1099 Since there are major incompatibilities between the legacy ABI and
1100 EABI, especially with regard to structure member alignment, this
1101 option also changes the kernel syscall calling convention to
1102 disambiguate both ABIs and allow for backward compatibility support
1103 (selected with CONFIG_OABI_COMPAT).
1105 To use this you need GCC version 4.0.0 or later.
1108 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1109 depends on AEABI && EXPERIMENTAL
1112 This option preserves the old syscall interface along with the
1113 new (ARM EABI) one. It also provides a compatibility layer to
1114 intercept syscalls that have structure arguments which layout
1115 in memory differs between the legacy ABI and the new ARM EABI
1116 (only for non "thumb" binaries). This option adds a tiny
1117 overhead to all syscalls and produces a slightly larger kernel.
1118 If you know you'll be using only pure EABI user space then you
1119 can say N here. If this option is not selected and you attempt
1120 to execute a legacy ABI binary then the result will be
1121 UNPREDICTABLE (in fact it can be predicted that it won't work
1122 at all). If in doubt say Y.
1124 config ARCH_HAS_HOLES_MEMORYMODEL
1127 # Discontigmem is deprecated
1128 config ARCH_DISCONTIGMEM_ENABLE
1131 config ARCH_SPARSEMEM_ENABLE
1134 config ARCH_SPARSEMEM_DEFAULT
1135 def_bool ARCH_SPARSEMEM_ENABLE
1137 config ARCH_SELECT_MEMORY_MODEL
1138 def_bool ARCH_DISCONTIGMEM_ENABLE && ARCH_SPARSEMEM_ENABLE
1142 default "4" if ARCH_LH7A40X
1144 depends on NEED_MULTIPLE_NODES
1147 bool "High Memory Support (EXPERIMENTAL)"
1148 depends on MMU && EXPERIMENTAL
1150 The address space of ARM processors is only 4 Gigabytes large
1151 and it has to accommodate user address space, kernel address
1152 space as well as some memory mapped IO. That means that, if you
1153 have a large amount of physical memory and/or IO, not all of the
1154 memory can be "permanently mapped" by the kernel. The physical
1155 memory that is not permanently mapped is called "high memory".
1157 Depending on the selected kernel/user memory split, minimum
1158 vmalloc space and actual amount of RAM, you may not need this
1159 option which should result in a slightly faster kernel.
1164 bool "Allocate 2nd-level pagetables from highmem"
1166 depends on !OUTER_CACHE
1171 bool "Timer and CPU usage LEDs"
1172 depends on ARCH_CDB89712 || ARCH_EBSA110 || \
1173 ARCH_EBSA285 || ARCH_INTEGRATOR || \
1174 ARCH_LUBBOCK || MACH_MAINSTONE || ARCH_NETWINDER || \
1175 ARCH_OMAP || ARCH_P720T || ARCH_PXA_IDP || \
1176 ARCH_SA1100 || ARCH_SHARK || ARCH_VERSATILE || \
1177 ARCH_AT91 || ARCH_DAVINCI || \
1178 ARCH_KS8695 || MACH_RD88F5182 || ARCH_REALVIEW
1180 If you say Y here, the LEDs on your machine will be used
1181 to provide useful information about your current system status.
1183 If you are compiling a kernel for a NetWinder or EBSA-285, you will
1184 be able to select which LEDs are active using the options below. If
1185 you are compiling a kernel for the EBSA-110 or the LART however, the
1186 red LED will simply flash regularly to indicate that the system is
1187 still functional. It is safe to say Y here if you have a CATS
1188 system, but the driver will do nothing.
1191 bool "Timer LED" if (!ARCH_CDB89712 && !ARCH_OMAP) || \
1192 OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1193 || MACH_OMAP_PERSEUS2
1195 depends on !GENERIC_CLOCKEVENTS
1196 default y if ARCH_EBSA110
1198 If you say Y here, one of the system LEDs (the green one on the
1199 NetWinder, the amber one on the EBSA285, or the red one on the LART)
1200 will flash regularly to indicate that the system is still
1201 operational. This is mainly useful to kernel hackers who are
1202 debugging unstable kernels.
1204 The LART uses the same LED for both Timer LED and CPU usage LED
1205 functions. You may choose to use both, but the Timer LED function
1206 will overrule the CPU usage LED.
1209 bool "CPU usage LED" if (!ARCH_CDB89712 && !ARCH_EBSA110 && \
1211 || OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1212 || MACH_OMAP_PERSEUS2
1215 If you say Y here, the red LED will be used to give a good real
1216 time indication of CPU usage, by lighting whenever the idle task
1217 is not currently executing.
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.
1223 config ALIGNMENT_TRAP
1225 depends on CPU_CP15_MMU
1226 default y if !ARCH_EBSA110
1228 ARM processors cannot fetch/store information which is not
1229 naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1230 address divisible by 4. On 32-bit ARM processors, these non-aligned
1231 fetch/store instructions will be emulated in software if you say
1232 here, which has a severe performance impact. This is necessary for
1233 correct operation of some network protocols. With an IP-only
1234 configuration it is safe to say N, otherwise say Y.
1236 config UACCESS_WITH_MEMCPY
1237 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user() (EXPERIMENTAL)"
1238 depends on MMU && EXPERIMENTAL
1239 default y if CPU_FEROCEON
1241 Implement faster copy_to_user and clear_user methods for CPU
1242 cores where a 8-word STM instruction give significantly higher
1243 memory write throughput than a sequence of individual 32bit stores.
1245 A possible side effect is a slight increase in scheduling latency
1246 between threads sharing the same address space if they invoke
1247 such copy operations with large buffers.
1249 However, if the CPU data cache is using a write-allocate mode,
1250 this option is unlikely to provide any performance gain.
1256 # Compressed boot loader in ROM. Yes, we really want to ask about
1257 # TEXT and BSS so we preserve their values in the config files.
1258 config ZBOOT_ROM_TEXT
1259 hex "Compressed ROM boot loader base address"
1262 The physical address at which the ROM-able zImage is to be
1263 placed in the target. Platforms which normally make use of
1264 ROM-able zImage formats normally set this to a suitable
1265 value in their defconfig file.
1267 If ZBOOT_ROM is not enabled, this has no effect.
1269 config ZBOOT_ROM_BSS
1270 hex "Compressed ROM boot loader BSS address"
1273 The base address of an area of read/write memory in the target
1274 for the ROM-able zImage which must be available while the
1275 decompressor is running. It must be large enough to hold the
1276 entire decompressed kernel plus an additional 128 KiB.
1277 Platforms which normally make use of ROM-able zImage formats
1278 normally set this to a suitable value in their defconfig file.
1280 If ZBOOT_ROM is not enabled, this has no effect.
1283 bool "Compressed boot loader in ROM/flash"
1284 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1286 Say Y here if you intend to execute your compressed kernel image
1287 (zImage) directly from ROM or flash. If unsure, say N.
1290 string "Default kernel command string"
1293 On some architectures (EBSA110 and CATS), there is currently no way
1294 for the boot loader to pass arguments to the kernel. For these
1295 architectures, you should supply some command-line options at build
1296 time by entering them here. As a minimum, you should specify the
1297 memory size and the root device (e.g., mem=64M root=/dev/nfs).
1300 bool "Kernel Execute-In-Place from ROM"
1301 depends on !ZBOOT_ROM
1303 Execute-In-Place allows the kernel to run from non-volatile storage
1304 directly addressable by the CPU, such as NOR flash. This saves RAM
1305 space since the text section of the kernel is not loaded from flash
1306 to RAM. Read-write sections, such as the data section and stack,
1307 are still copied to RAM. The XIP kernel is not compressed since
1308 it has to run directly from flash, so it will take more space to
1309 store it. The flash address used to link the kernel object files,
1310 and for storing it, is configuration dependent. Therefore, if you
1311 say Y here, you must know the proper physical address where to
1312 store the kernel image depending on your own flash memory usage.
1314 Also note that the make target becomes "make xipImage" rather than
1315 "make zImage" or "make Image". The final kernel binary to put in
1316 ROM memory will be arch/arm/boot/xipImage.
1320 config XIP_PHYS_ADDR
1321 hex "XIP Kernel Physical Location"
1322 depends on XIP_KERNEL
1323 default "0x00080000"
1325 This is the physical address in your flash memory the kernel will
1326 be linked for and stored to. This address is dependent on your
1330 bool "Kexec system call (EXPERIMENTAL)"
1331 depends on EXPERIMENTAL
1333 kexec is a system call that implements the ability to shutdown your
1334 current kernel, and to start another kernel. It is like a reboot
1335 but it is independent of the system firmware. And like a reboot
1336 you can start any kernel with it, not just Linux.
1338 It is an ongoing process to be certain the hardware in a machine
1339 is properly shutdown, so do not be surprised if this code does not
1340 initially work for you. It may help to enable device hotplugging
1344 bool "Export atags in procfs"
1348 Should the atags used to boot the kernel be exported in an "atags"
1349 file in procfs. Useful with kexec.
1353 menu "CPU Power Management"
1357 source "drivers/cpufreq/Kconfig"
1359 config CPU_FREQ_SA1100
1361 depends on CPU_FREQ && (SA1100_H3100 || SA1100_H3600 || SA1100_LART || SA1100_PLEB || SA1100_BADGE4 || SA1100_HACKKIT)
1364 config CPU_FREQ_SA1110
1366 depends on CPU_FREQ && (SA1100_ASSABET || SA1100_CERF || SA1100_PT_SYSTEM3)
1369 config CPU_FREQ_INTEGRATOR
1370 tristate "CPUfreq driver for ARM Integrator CPUs"
1371 depends on ARCH_INTEGRATOR && CPU_FREQ
1374 This enables the CPUfreq driver for ARM Integrator CPUs.
1376 For details, take a look at <file:Documentation/cpu-freq>.
1382 depends on CPU_FREQ && ARCH_PXA && PXA25x
1384 select CPU_FREQ_DEFAULT_GOV_USERSPACE
1386 config CPU_FREQ_S3C64XX
1387 bool "CPUfreq support for Samsung S3C64XX CPUs"
1388 depends on CPU_FREQ && CPU_S3C6410
1393 Internal configuration node for common cpufreq on Samsung SoC
1395 config CPU_FREQ_S3C24XX
1396 bool "CPUfreq driver for Samsung S3C24XX series CPUs"
1397 depends on ARCH_S3C2410 && CPU_FREQ && EXPERIMENTAL
1400 This enables the CPUfreq driver for the Samsung S3C24XX family
1403 For details, take a look at <file:Documentation/cpu-freq>.
1407 config CPU_FREQ_S3C24XX_PLL
1408 bool "Support CPUfreq changing of PLL frequency"
1409 depends on CPU_FREQ_S3C24XX && EXPERIMENTAL
1411 Compile in support for changing the PLL frequency from the
1412 S3C24XX series CPUfreq driver. The PLL takes time to settle
1413 after a frequency change, so by default it is not enabled.
1415 This also means that the PLL tables for the selected CPU(s) will
1416 be built which may increase the size of the kernel image.
1418 config CPU_FREQ_S3C24XX_DEBUG
1419 bool "Debug CPUfreq Samsung driver core"
1420 depends on CPU_FREQ_S3C24XX
1422 Enable s3c_freq_dbg for the Samsung S3C CPUfreq core
1424 config CPU_FREQ_S3C24XX_IODEBUG
1425 bool "Debug CPUfreq Samsung driver IO timing"
1426 depends on CPU_FREQ_S3C24XX
1428 Enable s3c_freq_iodbg for the Samsung S3C CPUfreq core
1430 config CPU_FREQ_S3C24XX_DEBUGFS
1431 bool "Export debugfs for CPUFreq"
1432 depends on CPU_FREQ_S3C24XX && DEBUG_FS
1434 Export status information via debugfs.
1438 source "drivers/cpuidle/Kconfig"
1442 menu "Floating point emulation"
1444 comment "At least one emulation must be selected"
1447 bool "NWFPE math emulation"
1448 depends on !AEABI || OABI_COMPAT
1450 Say Y to include the NWFPE floating point emulator in the kernel.
1451 This is necessary to run most binaries. Linux does not currently
1452 support floating point hardware so you need to say Y here even if
1453 your machine has an FPA or floating point co-processor podule.
1455 You may say N here if you are going to load the Acorn FPEmulator
1456 early in the bootup.
1459 bool "Support extended precision"
1460 depends on FPE_NWFPE
1462 Say Y to include 80-bit support in the kernel floating-point
1463 emulator. Otherwise, only 32 and 64-bit support is compiled in.
1464 Note that gcc does not generate 80-bit operations by default,
1465 so in most cases this option only enlarges the size of the
1466 floating point emulator without any good reason.
1468 You almost surely want to say N here.
1471 bool "FastFPE math emulation (EXPERIMENTAL)"
1472 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3 && EXPERIMENTAL
1474 Say Y here to include the FAST floating point emulator in the kernel.
1475 This is an experimental much faster emulator which now also has full
1476 precision for the mantissa. It does not support any exceptions.
1477 It is very simple, and approximately 3-6 times faster than NWFPE.
1479 It should be sufficient for most programs. It may be not suitable
1480 for scientific calculations, but you have to check this for yourself.
1481 If you do not feel you need a faster FP emulation you should better
1485 bool "VFP-format floating point maths"
1486 depends on CPU_V6 || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
1488 Say Y to include VFP support code in the kernel. This is needed
1489 if your hardware includes a VFP unit.
1491 Please see <file:Documentation/arm/VFP/release-notes.txt> for
1492 release notes and additional status information.
1494 Say N if your target does not have VFP hardware.
1502 bool "Advanced SIMD (NEON) Extension support"
1503 depends on VFPv3 && CPU_V7
1505 Say Y to include support code for NEON, the ARMv7 Advanced SIMD
1510 menu "Userspace binary formats"
1512 source "fs/Kconfig.binfmt"
1515 tristate "RISC OS personality"
1518 Say Y here to include the kernel code necessary if you want to run
1519 Acorn RISC OS/Arthur binaries under Linux. This code is still very
1520 experimental; if this sounds frightening, say N and sleep in peace.
1521 You can also say M here to compile this support as a module (which
1522 will be called arthur).
1526 menu "Power management options"
1528 source "kernel/power/Kconfig"
1530 config ARCH_SUSPEND_POSSIBLE
1535 source "net/Kconfig"
1537 source "drivers/Kconfig"
1541 source "arch/arm/Kconfig.debug"
1543 source "security/Kconfig"
1545 source "crypto/Kconfig"
1547 source "lib/Kconfig"