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
55 The Extended Industry Standard Architecture (EISA) bus was
56 developed as an open alternative to the IBM MicroChannel bus.
58 The EISA bus provided some of the features of the IBM MicroChannel
59 bus while maintaining backward compatibility with cards made for
60 the older ISA bus. The EISA bus saw limited use between 1988 and
61 1995 when it was made obsolete by the PCI bus.
63 Say Y here if you are building a kernel for an EISA-based machine.
73 MicroChannel Architecture is found in some IBM PS/2 machines and
74 laptops. It is a bus system similar to PCI or ISA. See
75 <file:Documentation/mca.txt> (and especially the web page given
76 there) before attempting to build an MCA bus kernel.
78 config GENERIC_HARDIRQS
82 config STACKTRACE_SUPPORT
86 config HAVE_LATENCYTOP_SUPPORT
91 config LOCKDEP_SUPPORT
95 config TRACE_IRQFLAGS_SUPPORT
99 config HARDIRQS_SW_RESEND
103 config GENERIC_IRQ_PROBE
107 config GENERIC_LOCKBREAK
110 depends on SMP && PREEMPT
112 config RWSEM_GENERIC_SPINLOCK
116 config RWSEM_XCHGADD_ALGORITHM
119 config ARCH_HAS_ILOG2_U32
122 config ARCH_HAS_ILOG2_U64
125 config ARCH_HAS_CPUFREQ
128 Internal node to signify that the ARCH has CPUFREQ support
129 and that the relevant menu configurations are displayed for
132 config GENERIC_HWEIGHT
136 config GENERIC_CALIBRATE_DELAY
140 config ARCH_MAY_HAVE_PC_FDC
146 config GENERIC_ISA_DMA
155 config GENERIC_HARDIRQS_NO__DO_IRQ
160 config OPROFILE_ARMV6
162 depends on CPU_V6 && !SMP
163 select OPROFILE_ARM11_CORE
165 config OPROFILE_MPCORE
167 depends on CPU_V6 && SMP
168 select OPROFILE_ARM11_CORE
170 config OPROFILE_ARM11_CORE
173 config OPROFILE_ARMV7
175 depends on CPU_V7 && !SMP
182 default 0xffff0000 if MMU || CPU_HIGH_VECTOR
183 default DRAM_BASE if REMAP_VECTORS_TO_RAM
186 The base address of exception vectors.
188 source "init/Kconfig"
190 source "kernel/Kconfig.freezer"
195 bool "MMU-based Paged Memory Management Support"
198 Select if you want MMU-based virtualised addressing space
199 support by paged memory management. If unsure, say 'Y'.
202 prompt "ARM system type"
203 default ARCH_VERSATILE
206 bool "Agilent AAEC-2000 based"
211 This enables support for systems based on the Agilent AAEC-2000
213 config ARCH_INTEGRATOR
214 bool "ARM Ltd. Integrator family"
216 select ARCH_HAS_CPUFREQ
221 Support for ARM's Integrator platform.
224 bool "ARM Ltd. RealView family"
230 select GENERIC_CLOCKEVENTS
232 This enables support for ARM Ltd RealView boards.
234 config ARCH_VERSATILE
235 bool "ARM Ltd. Versatile family"
242 select GENERIC_CLOCKEVENTS
244 This enables support for ARM Ltd Versatile board.
249 select ARCH_REQUIRE_GPIOLIB
252 This enables support for systems based on the Atmel AT91RM9200,
253 AT91SAM9 and AT91CAP9 processors.
256 bool "Cirrus Logic CLPS711x/EP721x-based"
259 Support for Cirrus Logic 711x/721x based boards.
262 bool "Cortina Systems Gemini"
265 select ARCH_REQUIRE_GPIOLIB
267 Support for the Cortina Systems Gemini family SoCs
275 This is an evaluation board for the StrongARM processor available
276 from Digital. It has limited hardware on-board, including an
277 Ethernet interface, two PCMCIA sockets, two serial ports and a
288 select ARCH_REQUIRE_GPIOLIB
289 select ARCH_HAS_HOLES_MEMORYMODEL
291 This enables support for the Cirrus EP93xx series of CPUs.
293 config ARCH_FOOTBRIDGE
298 Support for systems based on the DC21285 companion chip
299 ("FootBridge"), such as the Simtec CATS and the Rebel NetWinder.
302 bool "Freescale MXC/iMX-based"
304 select GENERIC_CLOCKEVENTS
307 select ARCH_REQUIRE_GPIOLIB
310 Support for Freescale MXC/iMX-based family of processors
313 bool "Freescale STMP3xxx"
317 select ARCH_REQUIRE_GPIOLIB
319 select GENERIC_CLOCKEVENTS
321 select USB_ARCH_HAS_EHCI
323 Support for systems based on the Freescale 3xxx CPUs.
326 bool "Hilscher NetX based"
329 select GENERIC_CLOCKEVENTS
332 This enables support for systems based on the Hilscher NetX Soc
335 bool "Hynix HMS720x-based"
339 This enables support for systems based on the Hynix HMS720x
342 bool "STMicroelectronics Nomadik"
349 select GENERIC_CLOCKEVENTS
351 select ARCH_REQUIRE_GPIOLIB
353 Support for the Nomadik platform by ST-Ericsson
361 select ARCH_SUPPORTS_MSI
364 Support for Intel's IOP13XX (XScale) family of processors.
373 select ARCH_REQUIRE_GPIOLIB
375 Support for Intel's 80219 and IOP32X (XScale) family of
385 select ARCH_REQUIRE_GPIOLIB
387 Support for Intel's IOP33X (XScale) family of processors.
395 Support for Intel's IXP23xx (XScale) family of processors.
398 bool "IXP2400/2800-based"
403 Support for Intel's IXP2400/2800 (XScale) family of processors.
411 select GENERIC_CLOCKEVENTS
412 select DMABOUNCE if PCI
414 Support for Intel's IXP4XX (XScale) family of processors.
421 Say Y here if you intend to run this kernel on a LinkUp Systems
422 L7200 Software Development Board which uses an ARM720T processor.
423 Information on this board can be obtained at:
425 <http://www.linkupsys.com/>
427 If you have any questions or comments about the Linux kernel port
428 to this board, send e-mail to <sjhill@cotw.com>.
431 bool "Marvell Kirkwood"
435 select ARCH_REQUIRE_GPIOLIB
437 select GENERIC_CLOCKEVENTS
440 Support for the following Marvell Kirkwood series SoCs:
441 88F6180, 88F6192 and 88F6281.
444 bool "Marvell Loki (88RC8480)"
447 select GENERIC_CLOCKEVENTS
450 Support for the Marvell Loki (88RC8480) SoC.
453 bool "Marvell MV78xx0"
457 select ARCH_REQUIRE_GPIOLIB
459 select GENERIC_CLOCKEVENTS
462 Support for the following Marvell MV78xx0 series SoCs:
471 select ARCH_REQUIRE_GPIOLIB
473 select GENERIC_CLOCKEVENTS
476 Support for the following Marvell Orion 5x series SoCs:
477 Orion-1 (5181), Orion-VoIP (5181L), Orion-NAS (5182),
478 Orion-2 (5281), Orion-1-90 (6183).
481 bool "Marvell PXA168/910"
484 select ARCH_REQUIRE_GPIOLIB
488 select GENERIC_CLOCKEVENTS
492 Support for Marvell's PXA168/910 processor line.
495 bool "Micrel/Kendin KS8695"
498 select ARCH_REQUIRE_GPIOLIB
500 Support for Micrel/Kendin KS8695 "Centaur" (ARM922T) based
501 System-on-Chip devices.
504 bool "NetSilicon NS9xxx"
508 select GENERIC_CLOCKEVENTS
511 Say Y here if you intend to run this kernel on a NetSilicon NS9xxx
514 <http://www.digi.com/products/microprocessors/index.jsp>
517 bool "Nuvoton W90X900 CPU"
519 select ARCH_REQUIRE_GPIOLIB
523 Support for Nuvoton (Winbond logic dept.) ARM9 processor,You
524 can login www.mcuos.com or www.nuvoton.com to know more.
527 bool "Philips Nexperia PNX4008 Mobile"
531 This enables support for Philips PNX4008 mobile platform.
534 bool "PXA2xx/PXA3xx-based"
537 select ARCH_HAS_CPUFREQ
541 select ARCH_REQUIRE_GPIOLIB
543 select GENERIC_CLOCKEVENTS
547 Support for Intel/Marvell's PXA2xx/PXA3xx processor line.
553 select GENERIC_CLOCKEVENTS
555 Support for Qualcomm MSM7K based systems. This runs on the ARM11
556 apps processor of the MSM7K and depends on a shared memory
557 interface to the ARM9 modem processor which runs the baseband stack
558 and controls some vital subsystems (clock and power control, etc).
565 select ARCH_MAY_HAVE_PC_FDC
566 select HAVE_PATA_PLATFORM
569 select ARCH_SPARSEMEM_ENABLE
571 On the Acorn Risc-PC, Linux can support the internal IDE disk and
572 CD-ROM interface, serial and parallel port, and the floppy drive.
578 select ARCH_SPARSEMEM_ENABLE
580 select ARCH_HAS_CPUFREQ
583 select GENERIC_CLOCKEVENTS
586 select ARCH_REQUIRE_GPIOLIB
588 Support for StrongARM 11x0 based boards.
591 bool "Samsung S3C2410, S3C2412, S3C2413, S3C2440, S3C2442, S3C2443"
593 select ARCH_HAS_CPUFREQ
596 Samsung S3C2410X CPU based systems, such as the Simtec Electronics
597 BAST (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or
598 the Samsung SMDK2410 development board (and derivatives).
601 bool "Samsung S3C64XX"
604 select ARCH_HAS_CPUFREQ
606 Samsung S3C64XX series based systems
609 bool "Samsung S5PC1XX"
614 Samsung S5PC1XX series based systems
624 Support for the StrongARM based Digital DNARD machine, also known
625 as "Shark" (<http://www.shark-linux.de/shark.html>).
630 select ARCH_DISCONTIGMEM_ENABLE if !LH7A40X_CONTIGMEM
631 select ARCH_SPARSEMEM_ENABLE if !LH7A40X_CONTIGMEM
633 Say Y here for systems based on one of the Sharp LH7A40X
634 System on a Chip processors. These CPUs include an ARM922T
635 core with a wide array of integrated devices for
636 hand-held and low-power applications.
639 bool "ST-Ericsson U300 Series"
645 select GENERIC_CLOCKEVENTS
650 Support for ST-Ericsson U300 series mobile platforms.
656 select GENERIC_CLOCKEVENTS
658 select ARCH_REQUIRE_GPIOLIB
663 select GENERIC_ALLOCATOR
665 Support for TI's DaVinci platform.
671 select ARCH_REQUIRE_GPIOLIB
672 select ARCH_HAS_CPUFREQ
674 select GENERIC_CLOCKEVENTS
676 Support for TI's OMAP platform (OMAP1 and OMAP2).
680 source "arch/arm/mach-clps711x/Kconfig"
682 source "arch/arm/mach-ep93xx/Kconfig"
684 source "arch/arm/mach-footbridge/Kconfig"
686 source "arch/arm/mach-gemini/Kconfig"
688 source "arch/arm/mach-integrator/Kconfig"
690 source "arch/arm/mach-iop32x/Kconfig"
692 source "arch/arm/mach-iop33x/Kconfig"
694 source "arch/arm/mach-iop13xx/Kconfig"
696 source "arch/arm/mach-ixp4xx/Kconfig"
698 source "arch/arm/mach-ixp2000/Kconfig"
700 source "arch/arm/mach-ixp23xx/Kconfig"
702 source "arch/arm/mach-loki/Kconfig"
704 source "arch/arm/mach-mv78xx0/Kconfig"
706 source "arch/arm/mach-pxa/Kconfig"
707 source "arch/arm/plat-pxa/Kconfig"
709 source "arch/arm/mach-mmp/Kconfig"
711 source "arch/arm/mach-sa1100/Kconfig"
713 source "arch/arm/plat-omap/Kconfig"
715 source "arch/arm/mach-omap1/Kconfig"
717 source "arch/arm/mach-omap2/Kconfig"
719 source "arch/arm/mach-orion5x/Kconfig"
721 source "arch/arm/mach-kirkwood/Kconfig"
723 source "arch/arm/plat-s3c24xx/Kconfig"
724 source "arch/arm/plat-s3c64xx/Kconfig"
725 source "arch/arm/plat-s3c/Kconfig"
726 source "arch/arm/plat-s5pc1xx/Kconfig"
729 source "arch/arm/mach-s3c2400/Kconfig"
730 source "arch/arm/mach-s3c2410/Kconfig"
731 source "arch/arm/mach-s3c2412/Kconfig"
732 source "arch/arm/mach-s3c2440/Kconfig"
733 source "arch/arm/mach-s3c2442/Kconfig"
734 source "arch/arm/mach-s3c2443/Kconfig"
738 source "arch/arm/mach-s3c6400/Kconfig"
739 source "arch/arm/mach-s3c6410/Kconfig"
742 source "arch/arm/plat-stmp3xxx/Kconfig"
745 source "arch/arm/mach-s5pc100/Kconfig"
748 source "arch/arm/mach-lh7a40x/Kconfig"
750 source "arch/arm/mach-h720x/Kconfig"
752 source "arch/arm/mach-versatile/Kconfig"
754 source "arch/arm/mach-aaec2000/Kconfig"
756 source "arch/arm/mach-realview/Kconfig"
758 source "arch/arm/mach-at91/Kconfig"
760 source "arch/arm/plat-mxc/Kconfig"
762 source "arch/arm/mach-nomadik/Kconfig"
764 source "arch/arm/mach-netx/Kconfig"
766 source "arch/arm/mach-ns9xxx/Kconfig"
768 source "arch/arm/mach-davinci/Kconfig"
770 source "arch/arm/mach-ks8695/Kconfig"
772 source "arch/arm/mach-msm/Kconfig"
774 source "arch/arm/mach-u300/Kconfig"
776 source "arch/arm/mach-w90x900/Kconfig"
778 # Definitions to make life easier
791 source arch/arm/mm/Kconfig
794 bool "Enable iWMMXt support"
795 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK
796 default y if PXA27x || PXA3xx || ARCH_MMP
798 Enable support for iWMMXt context switching at run time if
799 running on a CPU that supports it.
801 # bool 'Use XScale PMU as timer source' CONFIG_XSCALE_PMU_TIMER
804 depends on CPU_XSCALE && !XSCALE_PMU_TIMER
808 source "arch/arm/Kconfig-nommu"
811 config ARM_ERRATA_411920
812 bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
813 depends on CPU_V6 && !SMP
815 Invalidation of the Instruction Cache operation can
816 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
817 It does not affect the MPCore. This option enables the ARM Ltd.
818 recommended workaround.
820 config ARM_ERRATA_430973
821 bool "ARM errata: Stale prediction on replaced interworking branch"
824 This option enables the workaround for the 430973 Cortex-A8
825 (r1p0..r1p2) erratum. If a code sequence containing an ARM/Thumb
826 interworking branch is replaced with another code sequence at the
827 same virtual address, whether due to self-modifying code or virtual
828 to physical address re-mapping, Cortex-A8 does not recover from the
829 stale interworking branch prediction. This results in Cortex-A8
830 executing the new code sequence in the incorrect ARM or Thumb state.
831 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
832 and also flushes the branch target cache at every context switch.
833 Note that setting specific bits in the ACTLR register may not be
834 available in non-secure mode.
836 config ARM_ERRATA_458693
837 bool "ARM errata: Processor deadlock when a false hazard is created"
840 This option enables the workaround for the 458693 Cortex-A8 (r2p0)
841 erratum. For very specific sequences of memory operations, it is
842 possible for a hazard condition intended for a cache line to instead
843 be incorrectly associated with a different cache line. This false
844 hazard might then cause a processor deadlock. The workaround enables
845 the L1 caching of the NEON accesses and disables the PLD instruction
846 in the ACTLR register. Note that setting specific bits in the ACTLR
847 register may not be available in non-secure mode.
849 config ARM_ERRATA_460075
850 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
853 This option enables the workaround for the 460075 Cortex-A8 (r2p0)
854 erratum. Any asynchronous access to the L2 cache may encounter a
855 situation in which recent store transactions to the L2 cache are lost
856 and overwritten with stale memory contents from external memory. The
857 workaround disables the write-allocate mode for the L2 cache via the
858 ACTLR register. Note that setting specific bits in the ACTLR register
859 may not be available in non-secure mode.
863 source "arch/arm/common/Kconfig"
865 config FORCE_MAX_ZONEORDER
878 Find out whether you have ISA slots on your motherboard. ISA is the
879 name of a bus system, i.e. the way the CPU talks to the other stuff
880 inside your box. Other bus systems are PCI, EISA, MicroChannel
881 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
882 newer boards don't support it. If you have ISA, say Y, otherwise N.
884 # Select ISA DMA controller support
889 # Select ISA DMA interface
894 bool "PCI support" if ARCH_INTEGRATOR_AP || ARCH_VERSATILE_PB || ARCH_IXP4XX || ARCH_KS8695 || MACH_ARMCORE
896 Find out whether you have a PCI motherboard. PCI is the name of a
897 bus system, i.e. the way the CPU talks to the other stuff inside
898 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
899 VESA. If you have PCI, say Y, otherwise N.
904 # Select the host bridge type
905 config PCI_HOST_VIA82C505
907 depends on PCI && ARCH_SHARK
910 config PCI_HOST_ITE8152
912 depends on PCI && MACH_ARMCORE
916 source "drivers/pci/Kconfig"
918 source "drivers/pcmcia/Kconfig"
922 menu "Kernel Features"
924 source "kernel/time/Kconfig"
927 bool "Symmetric Multi-Processing (EXPERIMENTAL)"
928 depends on EXPERIMENTAL && (REALVIEW_EB_ARM11MP || REALVIEW_EB_A9MP ||\
929 MACH_REALVIEW_PB11MP || MACH_REALVIEW_PBX || ARCH_OMAP4)
930 depends on GENERIC_CLOCKEVENTS
931 select USE_GENERIC_SMP_HELPERS
932 select HAVE_ARM_SCU if (ARCH_REALVIEW || ARCH_OMAP4)
934 This enables support for systems with more than one CPU. If you have
935 a system with only one CPU, like most personal computers, say N. If
936 you have a system with more than one CPU, say Y.
938 If you say N here, the kernel will run on single and multiprocessor
939 machines, but will use only one CPU of a multiprocessor machine. If
940 you say Y here, the kernel will run on many, but not all, single
941 processor machines. On a single processor machine, the kernel will
942 run faster if you say N here.
944 See also <file:Documentation/i386/IO-APIC.txt>,
945 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
946 <http://www.linuxdoc.org/docs.html#howto>.
948 If you don't know what to do here, say N.
954 This option enables support for the ARM system coherency unit
960 This options enables support for the ARM timer and watchdog unit
963 prompt "Memory split"
966 Select the desired split between kernel and user memory.
968 If you are not absolutely sure what you are doing, leave this
972 bool "3G/1G user/kernel split"
974 bool "2G/2G user/kernel split"
976 bool "1G/3G user/kernel split"
981 default 0x40000000 if VMSPLIT_1G
982 default 0x80000000 if VMSPLIT_2G
986 int "Maximum number of CPUs (2-32)"
992 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
993 depends on SMP && HOTPLUG && EXPERIMENTAL
995 Say Y here to experiment with turning CPUs off and on. CPUs
996 can be controlled through /sys/devices/system/cpu.
999 bool "Use local timer interrupts"
1000 depends on SMP && (REALVIEW_EB_ARM11MP || MACH_REALVIEW_PB11MP || \
1001 REALVIEW_EB_A9MP || MACH_REALVIEW_PBX || ARCH_OMAP4)
1003 select HAVE_ARM_TWD if (ARCH_REALVIEW || ARCH_OMAP4)
1005 Enable support for local timers on SMP platforms, rather then the
1006 legacy IPI broadcast method. Local timers allows the system
1007 accounting to be spread across the timer interval, preventing a
1008 "thundering herd" at every timer tick.
1010 source kernel/Kconfig.preempt
1014 default 128 if ARCH_L7200
1015 default 200 if ARCH_EBSA110 || ARCH_S3C2410
1016 default OMAP_32K_TIMER_HZ if ARCH_OMAP && OMAP_32K_TIMER
1017 default AT91_TIMER_HZ if ARCH_AT91
1020 config THUMB2_KERNEL
1021 bool "Compile the kernel in Thumb-2 mode"
1022 depends on CPU_V7 && EXPERIMENTAL
1024 select ARM_ASM_UNIFIED
1026 By enabling this option, the kernel will be compiled in
1027 Thumb-2 mode. A compiler/assembler that understand the unified
1028 ARM-Thumb syntax is needed.
1032 config ARM_ASM_UNIFIED
1036 bool "Use the ARM EABI to compile the kernel"
1038 This option allows for the kernel to be compiled using the latest
1039 ARM ABI (aka EABI). This is only useful if you are using a user
1040 space environment that is also compiled with EABI.
1042 Since there are major incompatibilities between the legacy ABI and
1043 EABI, especially with regard to structure member alignment, this
1044 option also changes the kernel syscall calling convention to
1045 disambiguate both ABIs and allow for backward compatibility support
1046 (selected with CONFIG_OABI_COMPAT).
1048 To use this you need GCC version 4.0.0 or later.
1051 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1052 depends on AEABI && EXPERIMENTAL
1055 This option preserves the old syscall interface along with the
1056 new (ARM EABI) one. It also provides a compatibility layer to
1057 intercept syscalls that have structure arguments which layout
1058 in memory differs between the legacy ABI and the new ARM EABI
1059 (only for non "thumb" binaries). This option adds a tiny
1060 overhead to all syscalls and produces a slightly larger kernel.
1061 If you know you'll be using only pure EABI user space then you
1062 can say N here. If this option is not selected and you attempt
1063 to execute a legacy ABI binary then the result will be
1064 UNPREDICTABLE (in fact it can be predicted that it won't work
1065 at all). If in doubt say Y.
1067 config ARCH_HAS_HOLES_MEMORYMODEL
1070 # Discontigmem is deprecated
1071 config ARCH_DISCONTIGMEM_ENABLE
1074 config ARCH_SPARSEMEM_ENABLE
1077 config ARCH_SPARSEMEM_DEFAULT
1078 def_bool ARCH_SPARSEMEM_ENABLE
1080 config ARCH_SELECT_MEMORY_MODEL
1081 def_bool ARCH_DISCONTIGMEM_ENABLE && ARCH_SPARSEMEM_ENABLE
1085 default "4" if ARCH_LH7A40X
1087 depends on NEED_MULTIPLE_NODES
1090 bool "High Memory Support (EXPERIMENTAL)"
1091 depends on MMU && EXPERIMENTAL
1093 The address space of ARM processors is only 4 Gigabytes large
1094 and it has to accommodate user address space, kernel address
1095 space as well as some memory mapped IO. That means that, if you
1096 have a large amount of physical memory and/or IO, not all of the
1097 memory can be "permanently mapped" by the kernel. The physical
1098 memory that is not permanently mapped is called "high memory".
1100 Depending on the selected kernel/user memory split, minimum
1101 vmalloc space and actual amount of RAM, you may not need this
1102 option which should result in a slightly faster kernel.
1109 bool "Timer and CPU usage LEDs"
1110 depends on ARCH_CDB89712 || ARCH_EBSA110 || \
1111 ARCH_EBSA285 || ARCH_INTEGRATOR || \
1112 ARCH_LUBBOCK || MACH_MAINSTONE || ARCH_NETWINDER || \
1113 ARCH_OMAP || ARCH_P720T || ARCH_PXA_IDP || \
1114 ARCH_SA1100 || ARCH_SHARK || ARCH_VERSATILE || \
1115 ARCH_AT91 || ARCH_DAVINCI || \
1116 ARCH_KS8695 || MACH_RD88F5182 || ARCH_REALVIEW
1118 If you say Y here, the LEDs on your machine will be used
1119 to provide useful information about your current system status.
1121 If you are compiling a kernel for a NetWinder or EBSA-285, you will
1122 be able to select which LEDs are active using the options below. If
1123 you are compiling a kernel for the EBSA-110 or the LART however, the
1124 red LED will simply flash regularly to indicate that the system is
1125 still functional. It is safe to say Y here if you have a CATS
1126 system, but the driver will do nothing.
1129 bool "Timer LED" if (!ARCH_CDB89712 && !ARCH_OMAP) || \
1130 OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1131 || MACH_OMAP_PERSEUS2
1133 depends on !GENERIC_CLOCKEVENTS
1134 default y if ARCH_EBSA110
1136 If you say Y here, one of the system LEDs (the green one on the
1137 NetWinder, the amber one on the EBSA285, or the red one on the LART)
1138 will flash regularly to indicate that the system is still
1139 operational. This is mainly useful to kernel hackers who are
1140 debugging unstable kernels.
1142 The LART uses the same LED for both Timer LED and CPU usage LED
1143 functions. You may choose to use both, but the Timer LED function
1144 will overrule the CPU usage LED.
1147 bool "CPU usage LED" if (!ARCH_CDB89712 && !ARCH_EBSA110 && \
1149 || OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1150 || MACH_OMAP_PERSEUS2
1153 If you say Y here, the red LED will be used to give a good real
1154 time indication of CPU usage, by lighting whenever the idle task
1155 is not currently executing.
1157 The LART uses the same LED for both Timer LED and CPU usage LED
1158 functions. You may choose to use both, but the Timer LED function
1159 will overrule the CPU usage LED.
1161 config ALIGNMENT_TRAP
1163 depends on CPU_CP15_MMU
1164 default y if !ARCH_EBSA110
1166 ARM processors cannot fetch/store information which is not
1167 naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1168 address divisible by 4. On 32-bit ARM processors, these non-aligned
1169 fetch/store instructions will be emulated in software if you say
1170 here, which has a severe performance impact. This is necessary for
1171 correct operation of some network protocols. With an IP-only
1172 configuration it is safe to say N, otherwise say Y.
1174 config UACCESS_WITH_MEMCPY
1175 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user() (EXPERIMENTAL)"
1176 depends on MMU && EXPERIMENTAL
1177 default y if CPU_FEROCEON
1179 Implement faster copy_to_user and clear_user methods for CPU
1180 cores where a 8-word STM instruction give significantly higher
1181 memory write throughput than a sequence of individual 32bit stores.
1183 A possible side effect is a slight increase in scheduling latency
1184 between threads sharing the same address space if they invoke
1185 such copy operations with large buffers.
1187 However, if the CPU data cache is using a write-allocate mode,
1188 this option is unlikely to provide any performance gain.
1194 # Compressed boot loader in ROM. Yes, we really want to ask about
1195 # TEXT and BSS so we preserve their values in the config files.
1196 config ZBOOT_ROM_TEXT
1197 hex "Compressed ROM boot loader base address"
1200 The physical address at which the ROM-able zImage is to be
1201 placed in the target. Platforms which normally make use of
1202 ROM-able zImage formats normally set this to a suitable
1203 value in their defconfig file.
1205 If ZBOOT_ROM is not enabled, this has no effect.
1207 config ZBOOT_ROM_BSS
1208 hex "Compressed ROM boot loader BSS address"
1211 The base address of an area of read/write memory in the target
1212 for the ROM-able zImage which must be available while the
1213 decompressor is running. It must be large enough to hold the
1214 entire decompressed kernel plus an additional 128 KiB.
1215 Platforms which normally make use of ROM-able zImage formats
1216 normally set this to a suitable value in their defconfig file.
1218 If ZBOOT_ROM is not enabled, this has no effect.
1221 bool "Compressed boot loader in ROM/flash"
1222 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1224 Say Y here if you intend to execute your compressed kernel image
1225 (zImage) directly from ROM or flash. If unsure, say N.
1228 string "Default kernel command string"
1231 On some architectures (EBSA110 and CATS), there is currently no way
1232 for the boot loader to pass arguments to the kernel. For these
1233 architectures, you should supply some command-line options at build
1234 time by entering them here. As a minimum, you should specify the
1235 memory size and the root device (e.g., mem=64M root=/dev/nfs).
1238 bool "Kernel Execute-In-Place from ROM"
1239 depends on !ZBOOT_ROM
1241 Execute-In-Place allows the kernel to run from non-volatile storage
1242 directly addressable by the CPU, such as NOR flash. This saves RAM
1243 space since the text section of the kernel is not loaded from flash
1244 to RAM. Read-write sections, such as the data section and stack,
1245 are still copied to RAM. The XIP kernel is not compressed since
1246 it has to run directly from flash, so it will take more space to
1247 store it. The flash address used to link the kernel object files,
1248 and for storing it, is configuration dependent. Therefore, if you
1249 say Y here, you must know the proper physical address where to
1250 store the kernel image depending on your own flash memory usage.
1252 Also note that the make target becomes "make xipImage" rather than
1253 "make zImage" or "make Image". The final kernel binary to put in
1254 ROM memory will be arch/arm/boot/xipImage.
1258 config XIP_PHYS_ADDR
1259 hex "XIP Kernel Physical Location"
1260 depends on XIP_KERNEL
1261 default "0x00080000"
1263 This is the physical address in your flash memory the kernel will
1264 be linked for and stored to. This address is dependent on your
1268 bool "Kexec system call (EXPERIMENTAL)"
1269 depends on EXPERIMENTAL
1271 kexec is a system call that implements the ability to shutdown your
1272 current kernel, and to start another kernel. It is like a reboot
1273 but it is independent of the system firmware. And like a reboot
1274 you can start any kernel with it, not just Linux.
1276 It is an ongoing process to be certain the hardware in a machine
1277 is properly shutdown, so do not be surprised if this code does not
1278 initially work for you. It may help to enable device hotplugging
1282 bool "Export atags in procfs"
1286 Should the atags used to boot the kernel be exported in an "atags"
1287 file in procfs. Useful with kexec.
1291 menu "CPU Power Management"
1295 source "drivers/cpufreq/Kconfig"
1297 config CPU_FREQ_SA1100
1299 depends on CPU_FREQ && (SA1100_H3100 || SA1100_H3600 || SA1100_LART || SA1100_PLEB || SA1100_BADGE4 || SA1100_HACKKIT)
1302 config CPU_FREQ_SA1110
1304 depends on CPU_FREQ && (SA1100_ASSABET || SA1100_CERF || SA1100_PT_SYSTEM3)
1307 config CPU_FREQ_INTEGRATOR
1308 tristate "CPUfreq driver for ARM Integrator CPUs"
1309 depends on ARCH_INTEGRATOR && CPU_FREQ
1312 This enables the CPUfreq driver for ARM Integrator CPUs.
1314 For details, take a look at <file:Documentation/cpu-freq>.
1320 depends on CPU_FREQ && ARCH_PXA && PXA25x
1322 select CPU_FREQ_DEFAULT_GOV_USERSPACE
1324 config CPU_FREQ_S3C64XX
1325 bool "CPUfreq support for Samsung S3C64XX CPUs"
1326 depends on CPU_FREQ && CPU_S3C6410
1331 Internal configuration node for common cpufreq on Samsung SoC
1333 config CPU_FREQ_S3C24XX
1334 bool "CPUfreq driver for Samsung S3C24XX series CPUs"
1335 depends on ARCH_S3C2410 && CPU_FREQ && EXPERIMENTAL
1338 This enables the CPUfreq driver for the Samsung S3C24XX family
1341 For details, take a look at <file:Documentation/cpu-freq>.
1345 config CPU_FREQ_S3C24XX_PLL
1346 bool "Support CPUfreq changing of PLL frequency"
1347 depends on CPU_FREQ_S3C24XX && EXPERIMENTAL
1349 Compile in support for changing the PLL frequency from the
1350 S3C24XX series CPUfreq driver. The PLL takes time to settle
1351 after a frequency change, so by default it is not enabled.
1353 This also means that the PLL tables for the selected CPU(s) will
1354 be built which may increase the size of the kernel image.
1356 config CPU_FREQ_S3C24XX_DEBUG
1357 bool "Debug CPUfreq Samsung driver core"
1358 depends on CPU_FREQ_S3C24XX
1360 Enable s3c_freq_dbg for the Samsung S3C CPUfreq core
1362 config CPU_FREQ_S3C24XX_IODEBUG
1363 bool "Debug CPUfreq Samsung driver IO timing"
1364 depends on CPU_FREQ_S3C24XX
1366 Enable s3c_freq_iodbg for the Samsung S3C CPUfreq core
1368 config CPU_FREQ_S3C24XX_DEBUGFS
1369 bool "Export debugfs for CPUFreq"
1370 depends on CPU_FREQ_S3C24XX && DEBUG_FS
1372 Export status information via debugfs.
1376 source "drivers/cpuidle/Kconfig"
1380 menu "Floating point emulation"
1382 comment "At least one emulation must be selected"
1385 bool "NWFPE math emulation"
1386 depends on !AEABI || OABI_COMPAT
1388 Say Y to include the NWFPE floating point emulator in the kernel.
1389 This is necessary to run most binaries. Linux does not currently
1390 support floating point hardware so you need to say Y here even if
1391 your machine has an FPA or floating point co-processor podule.
1393 You may say N here if you are going to load the Acorn FPEmulator
1394 early in the bootup.
1397 bool "Support extended precision"
1398 depends on FPE_NWFPE
1400 Say Y to include 80-bit support in the kernel floating-point
1401 emulator. Otherwise, only 32 and 64-bit support is compiled in.
1402 Note that gcc does not generate 80-bit operations by default,
1403 so in most cases this option only enlarges the size of the
1404 floating point emulator without any good reason.
1406 You almost surely want to say N here.
1409 bool "FastFPE math emulation (EXPERIMENTAL)"
1410 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3 && EXPERIMENTAL
1412 Say Y here to include the FAST floating point emulator in the kernel.
1413 This is an experimental much faster emulator which now also has full
1414 precision for the mantissa. It does not support any exceptions.
1415 It is very simple, and approximately 3-6 times faster than NWFPE.
1417 It should be sufficient for most programs. It may be not suitable
1418 for scientific calculations, but you have to check this for yourself.
1419 If you do not feel you need a faster FP emulation you should better
1423 bool "VFP-format floating point maths"
1424 depends on CPU_V6 || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
1426 Say Y to include VFP support code in the kernel. This is needed
1427 if your hardware includes a VFP unit.
1429 Please see <file:Documentation/arm/VFP/release-notes.txt> for
1430 release notes and additional status information.
1432 Say N if your target does not have VFP hardware.
1440 bool "Advanced SIMD (NEON) Extension support"
1441 depends on VFPv3 && CPU_V7
1443 Say Y to include support code for NEON, the ARMv7 Advanced SIMD
1448 menu "Userspace binary formats"
1450 source "fs/Kconfig.binfmt"
1453 tristate "RISC OS personality"
1456 Say Y here to include the kernel code necessary if you want to run
1457 Acorn RISC OS/Arthur binaries under Linux. This code is still very
1458 experimental; if this sounds frightening, say N and sleep in peace.
1459 You can also say M here to compile this support as a module (which
1460 will be called arthur).
1464 menu "Power management options"
1466 source "kernel/power/Kconfig"
1468 config ARCH_SUSPEND_POSSIBLE
1473 source "net/Kconfig"
1475 source "drivers/Kconfig"
1479 source "arch/arm/Kconfig.debug"
1481 source "security/Kconfig"
1483 source "crypto/Kconfig"
1485 source "lib/Kconfig"