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
15 select GENERIC_ATOMIC64 if (!CPU_32v6K)
18 select HAVE_KPROBES if (!XIP_KERNEL)
19 select HAVE_KRETPROBES if (HAVE_KPROBES)
20 select HAVE_FUNCTION_TRACER if (!XIP_KERNEL)
21 select HAVE_GENERIC_DMA_COHERENT
22 select HAVE_KERNEL_GZIP
23 select HAVE_KERNEL_LZO
24 select HAVE_PERF_EVENTS
25 select PERF_USE_VMALLOC
27 The ARM series is a line of low-power-consumption RISC chip designs
28 licensed by ARM Ltd and targeted at embedded applications and
29 handhelds such as the Compaq IPAQ. ARM-based PCs are no longer
30 manufactured, but legacy ARM-based PC hardware remains popular in
31 Europe. There is an ARM Linux project with a web page at
32 <http://www.arm.linux.org.uk/>.
37 config SYS_SUPPORTS_APM_EMULATION
46 config GENERIC_CLOCKEVENTS
49 config GENERIC_CLOCKEVENTS_BROADCAST
51 depends on GENERIC_CLOCKEVENTS
52 default y if SMP && !LOCAL_TIMERS
56 select GENERIC_ALLOCATOR
67 The Extended Industry Standard Architecture (EISA) bus was
68 developed as an open alternative to the IBM MicroChannel bus.
70 The EISA bus provided some of the features of the IBM MicroChannel
71 bus while maintaining backward compatibility with cards made for
72 the older ISA bus. The EISA bus saw limited use between 1988 and
73 1995 when it was made obsolete by the PCI bus.
75 Say Y here if you are building a kernel for an EISA-based machine.
85 MicroChannel Architecture is found in some IBM PS/2 machines and
86 laptops. It is a bus system similar to PCI or ISA. See
87 <file:Documentation/mca.txt> (and especially the web page given
88 there) before attempting to build an MCA bus kernel.
90 config GENERIC_HARDIRQS
94 config STACKTRACE_SUPPORT
98 config HAVE_LATENCYTOP_SUPPORT
103 config LOCKDEP_SUPPORT
107 config TRACE_IRQFLAGS_SUPPORT
111 config HARDIRQS_SW_RESEND
115 config GENERIC_IRQ_PROBE
119 config GENERIC_LOCKBREAK
122 depends on SMP && PREEMPT
124 config RWSEM_GENERIC_SPINLOCK
128 config RWSEM_XCHGADD_ALGORITHM
131 config ARCH_HAS_ILOG2_U32
134 config ARCH_HAS_ILOG2_U64
137 config ARCH_HAS_CPUFREQ
140 Internal node to signify that the ARCH has CPUFREQ support
141 and that the relevant menu configurations are displayed for
144 config GENERIC_HWEIGHT
148 config GENERIC_CALIBRATE_DELAY
152 config ARCH_MAY_HAVE_PC_FDC
158 config NEED_DMA_MAP_STATE
161 config GENERIC_ISA_DMA
170 config GENERIC_HARDIRQS_NO__DO_IRQ
173 config ARM_L1_CACHE_SHIFT_6
176 Setting ARM L1 cache line size to 64 Bytes.
180 config OPROFILE_ARMV6
182 depends on CPU_V6 && !SMP
183 select OPROFILE_ARM11_CORE
185 config OPROFILE_MPCORE
187 depends on CPU_V6 && SMP
188 select OPROFILE_ARM11_CORE
190 config OPROFILE_ARM11_CORE
193 config OPROFILE_ARMV7
195 depends on CPU_V7 && !SMP
202 default 0xffff0000 if MMU || CPU_HIGH_VECTOR
203 default DRAM_BASE if REMAP_VECTORS_TO_RAM
206 The base address of exception vectors.
208 source "init/Kconfig"
210 source "kernel/Kconfig.freezer"
215 bool "MMU-based Paged Memory Management Support"
218 Select if you want MMU-based virtualised addressing space
219 support by paged memory management. If unsure, say 'Y'.
222 # The "ARM system type" choice list is ordered alphabetically by option
223 # text. Please add new entries in the option alphabetic order.
226 prompt "ARM system type"
227 default ARCH_VERSATILE
230 bool "Agilent AAEC-2000 based"
235 This enables support for systems based on the Agilent AAEC-2000
237 config ARCH_INTEGRATOR
238 bool "ARM Ltd. Integrator family"
240 select ARCH_HAS_CPUFREQ
245 Support for ARM's Integrator platform.
248 bool "ARM Ltd. RealView family"
254 select GENERIC_CLOCKEVENTS
255 select ARCH_WANT_OPTIONAL_GPIOLIB
257 This enables support for ARM Ltd RealView boards.
259 config ARCH_VERSATILE
260 bool "ARM Ltd. Versatile family"
267 select GENERIC_CLOCKEVENTS
268 select ARCH_WANT_OPTIONAL_GPIOLIB
270 This enables support for ARM Ltd Versatile board.
275 select ARCH_REQUIRE_GPIOLIB
278 This enables support for systems based on the Atmel AT91RM9200,
279 AT91SAM9 and AT91CAP9 processors.
282 bool "Broadcom BCMRING"
288 select GENERIC_CLOCKEVENTS
289 select ARCH_WANT_OPTIONAL_GPIOLIB
291 Support for Broadcom's BCMRing platform.
294 bool "Cirrus Logic CLPS711x/EP721x-based"
297 Support for Cirrus Logic 711x/721x based boards.
300 bool "Cortina Systems Gemini"
303 select ARCH_REQUIRE_GPIOLIB
305 Support for the Cortina Systems Gemini family SoCs
313 This is an evaluation board for the StrongARM processor available
314 from Digital. It has limited hardware on-board, including an
315 Ethernet interface, two PCMCIA sockets, two serial ports and a
326 select ARCH_REQUIRE_GPIOLIB
327 select ARCH_HAS_HOLES_MEMORYMODEL
329 This enables support for the Cirrus EP93xx series of CPUs.
331 config ARCH_FOOTBRIDGE
336 Support for systems based on the DC21285 companion chip
337 ("FootBridge"), such as the Simtec CATS and the Rebel NetWinder.
340 bool "Freescale MXC/iMX-based"
342 select GENERIC_CLOCKEVENTS
343 select ARCH_REQUIRE_GPIOLIB
347 Support for Freescale MXC/iMX-based family of processors
350 bool "Freescale STMP3xxx"
354 select ARCH_REQUIRE_GPIOLIB
356 select GENERIC_CLOCKEVENTS
358 select USB_ARCH_HAS_EHCI
360 Support for systems based on the Freescale 3xxx CPUs.
363 bool "Hilscher NetX based"
366 select GENERIC_CLOCKEVENTS
369 This enables support for systems based on the Hilscher NetX Soc
372 bool "Hynix HMS720x-based"
376 This enables support for systems based on the Hynix HMS720x
384 select ARCH_SUPPORTS_MSI
387 Support for Intel's IOP13XX (XScale) family of processors.
396 select ARCH_REQUIRE_GPIOLIB
398 Support for Intel's 80219 and IOP32X (XScale) family of
408 select ARCH_REQUIRE_GPIOLIB
410 Support for Intel's IOP33X (XScale) family of processors.
418 Support for Intel's IXP23xx (XScale) family of processors.
421 bool "IXP2400/2800-based"
426 Support for Intel's IXP2400/2800 (XScale) family of processors.
434 select GENERIC_CLOCKEVENTS
435 select DMABOUNCE if PCI
437 Support for Intel's IXP4XX (XScale) family of processors.
444 Say Y here if you intend to run this kernel on a LinkUp Systems
445 L7200 Software Development Board which uses an ARM720T processor.
446 Information on this board can be obtained at:
448 <http://www.linkupsys.com/>
450 If you have any questions or comments about the Linux kernel port
451 to this board, send e-mail to <sjhill@cotw.com>.
457 select ARCH_REQUIRE_GPIOLIB
459 select GENERIC_CLOCKEVENTS
462 Support for the Marvell Dove SoC 88AP510
465 bool "Marvell Kirkwood"
469 select ARCH_REQUIRE_GPIOLIB
471 select GENERIC_CLOCKEVENTS
474 Support for the following Marvell Kirkwood series SoCs:
475 88F6180, 88F6192 and 88F6281.
478 bool "Marvell Loki (88RC8480)"
481 select GENERIC_CLOCKEVENTS
484 Support for the Marvell Loki (88RC8480) SoC.
487 bool "Marvell MV78xx0"
491 select ARCH_REQUIRE_GPIOLIB
493 select GENERIC_CLOCKEVENTS
496 Support for the following Marvell MV78xx0 series SoCs:
505 select ARCH_REQUIRE_GPIOLIB
507 select GENERIC_CLOCKEVENTS
510 Support for the following Marvell Orion 5x series SoCs:
511 Orion-1 (5181), Orion-VoIP (5181L), Orion-NAS (5182),
512 Orion-2 (5281), Orion-1-90 (6183).
515 bool "Marvell PXA168/910/MMP2"
518 select ARCH_REQUIRE_GPIOLIB
522 select GENERIC_CLOCKEVENTS
526 Support for Marvell's PXA168/PXA910(MMP) and MMP2 processor line.
529 bool "Micrel/Kendin KS8695"
532 select ARCH_REQUIRE_GPIOLIB
534 Support for Micrel/Kendin KS8695 "Centaur" (ARM922T) based
535 System-on-Chip devices.
538 bool "NetSilicon NS9xxx"
542 select GENERIC_CLOCKEVENTS
545 Say Y here if you intend to run this kernel on a NetSilicon NS9xxx
548 <http://www.digi.com/products/microprocessors/index.jsp>
551 bool "Nuvoton W90X900 CPU"
553 select ARCH_REQUIRE_GPIOLIB
558 select GENERIC_CLOCKEVENTS
560 Support for Nuvoton (Winbond logic dept.) ARM9 processor,
561 At present, the w90x900 has been renamed nuc900, regarding
562 the ARM series product line, you can login the following
563 link address to know more.
565 <http://www.nuvoton.com/hq/enu/ProductAndSales/ProductLines/
566 ConsumerElectronicsIC/ARMMicrocontroller/ARMMicrocontroller>
569 bool "Nuvoton NUC93X CPU"
574 Support for Nuvoton (Winbond logic dept.) NUC93X MCU,The NUC93X is a
575 low-power and high performance MPEG-4/JPEG multimedia controller chip.
578 bool "Philips Nexperia PNX4008 Mobile"
583 This enables support for Philips PNX4008 mobile platform.
586 bool "PXA2xx/PXA3xx-based"
589 select ARCH_HAS_CPUFREQ
593 select ARCH_REQUIRE_GPIOLIB
595 select GENERIC_CLOCKEVENTS
599 Support for Intel/Marvell's PXA2xx/PXA3xx processor line.
605 select GENERIC_CLOCKEVENTS
607 Support for Qualcomm MSM7K based systems. This runs on the ARM11
608 apps processor of the MSM7K and depends on a shared memory
609 interface to the ARM9 modem processor which runs the baseband stack
610 and controls some vital subsystems (clock and power control, etc).
613 bool "Renesas SH-Mobile"
615 Support for Renesas's SH-Mobile ARM platforms
622 select ARCH_MAY_HAVE_PC_FDC
623 select HAVE_PATA_PLATFORM
626 select ARCH_SPARSEMEM_ENABLE
628 On the Acorn Risc-PC, Linux can support the internal IDE disk and
629 CD-ROM interface, serial and parallel port, and the floppy drive.
635 select ARCH_SPARSEMEM_ENABLE
637 select ARCH_HAS_CPUFREQ
641 select GENERIC_CLOCKEVENTS
644 select ARCH_REQUIRE_GPIOLIB
646 Support for StrongARM 11x0 based boards.
649 bool "Samsung S3C2410, S3C2412, S3C2413, S3C2440, S3C2442, S3C2443"
651 select ARCH_HAS_CPUFREQ
654 Samsung S3C2410X CPU based systems, such as the Simtec Electronics
655 BAST (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or
656 the Samsung SMDK2410 development board (and derivatives).
659 bool "Samsung S3C64XX"
666 select ARCH_HAS_CPUFREQ
667 select ARCH_REQUIRE_GPIOLIB
668 select SAMSUNG_CLKSRC
669 select SAMSUNG_IRQ_VIC_TIMER
670 select SAMSUNG_IRQ_UART
671 select S3C_GPIO_TRACK
672 select S3C_GPIO_PULL_UPDOWN
673 select S3C_GPIO_CFG_S3C24XX
674 select S3C_GPIO_CFG_S3C64XX
676 select USB_ARCH_HAS_OHCI
677 select SAMSUNG_GPIOLIB_4BIT
679 Samsung S3C64XX series based systems
682 bool "Samsung S5P6440"
687 Samsung S5P6440 CPU based systems
690 bool "Samsung S5P6442"
695 Samsung S5P6442 CPU based systems
698 bool "Samsung S5PC1XX"
702 select ARM_L1_CACHE_SHIFT_6
704 Samsung S5PC1XX series based systems
707 bool "Samsung S5PV210/S5PC110"
711 select ARM_L1_CACHE_SHIFT_6
713 Samsung S5PV210/S5PC110 series based systems
723 Support for the StrongARM based Digital DNARD machine, also known
724 as "Shark" (<http://www.shark-linux.de/shark.html>).
729 select ARCH_DISCONTIGMEM_ENABLE if !LH7A40X_CONTIGMEM
730 select ARCH_SPARSEMEM_ENABLE if !LH7A40X_CONTIGMEM
732 Say Y here for systems based on one of the Sharp LH7A40X
733 System on a Chip processors. These CPUs include an ARM922T
734 core with a wide array of integrated devices for
735 hand-held and low-power applications.
738 bool "ST-Ericsson U300 Series"
745 select GENERIC_CLOCKEVENTS
750 Support for ST-Ericsson U300 series mobile platforms.
753 bool "ST-Ericsson U8500 Series"
757 select GENERIC_CLOCKEVENTS
760 Support for ST-Ericsson's Ux500 architecture
763 bool "STMicroelectronics Nomadik"
770 select GENERIC_CLOCKEVENTS
772 select ARCH_REQUIRE_GPIOLIB
774 Support for the Nomadik platform by ST-Ericsson
780 select GENERIC_CLOCKEVENTS
782 select ARCH_REQUIRE_GPIOLIB
787 select GENERIC_ALLOCATOR
788 select ARCH_HAS_HOLES_MEMORYMODEL
790 Support for TI's DaVinci platform.
796 select ARCH_REQUIRE_GPIOLIB
797 select ARCH_HAS_CPUFREQ
799 select GENERIC_CLOCKEVENTS
800 select ARCH_HAS_HOLES_MEMORYMODEL
802 Support for TI's OMAP platform (OMAP1 and OMAP2).
807 # This is sorted alphabetically by mach-* pathname. However, plat-*
808 # Kconfigs may be included either alphabetically (according to the
809 # plat- suffix) or along side the corresponding mach-* source.
811 source "arch/arm/mach-aaec2000/Kconfig"
813 source "arch/arm/mach-at91/Kconfig"
815 source "arch/arm/mach-bcmring/Kconfig"
817 source "arch/arm/mach-clps711x/Kconfig"
819 source "arch/arm/mach-davinci/Kconfig"
821 source "arch/arm/mach-dove/Kconfig"
823 source "arch/arm/mach-ep93xx/Kconfig"
825 source "arch/arm/mach-footbridge/Kconfig"
827 source "arch/arm/mach-gemini/Kconfig"
829 source "arch/arm/mach-h720x/Kconfig"
831 source "arch/arm/mach-integrator/Kconfig"
833 source "arch/arm/mach-iop32x/Kconfig"
835 source "arch/arm/mach-iop33x/Kconfig"
837 source "arch/arm/mach-iop13xx/Kconfig"
839 source "arch/arm/mach-ixp4xx/Kconfig"
841 source "arch/arm/mach-ixp2000/Kconfig"
843 source "arch/arm/mach-ixp23xx/Kconfig"
845 source "arch/arm/mach-kirkwood/Kconfig"
847 source "arch/arm/mach-ks8695/Kconfig"
849 source "arch/arm/mach-lh7a40x/Kconfig"
851 source "arch/arm/mach-loki/Kconfig"
853 source "arch/arm/mach-msm/Kconfig"
855 source "arch/arm/mach-mv78xx0/Kconfig"
857 source "arch/arm/plat-mxc/Kconfig"
859 source "arch/arm/mach-netx/Kconfig"
861 source "arch/arm/mach-nomadik/Kconfig"
862 source "arch/arm/plat-nomadik/Kconfig"
864 source "arch/arm/mach-ns9xxx/Kconfig"
866 source "arch/arm/mach-nuc93x/Kconfig"
868 source "arch/arm/plat-omap/Kconfig"
870 source "arch/arm/mach-omap1/Kconfig"
872 source "arch/arm/mach-omap2/Kconfig"
874 source "arch/arm/mach-orion5x/Kconfig"
876 source "arch/arm/mach-pxa/Kconfig"
877 source "arch/arm/plat-pxa/Kconfig"
879 source "arch/arm/mach-mmp/Kconfig"
881 source "arch/arm/mach-realview/Kconfig"
883 source "arch/arm/mach-sa1100/Kconfig"
885 source "arch/arm/plat-samsung/Kconfig"
886 source "arch/arm/plat-s3c24xx/Kconfig"
887 source "arch/arm/plat-s5p/Kconfig"
888 source "arch/arm/plat-s5pc1xx/Kconfig"
891 source "arch/arm/mach-s3c2400/Kconfig"
892 source "arch/arm/mach-s3c2410/Kconfig"
893 source "arch/arm/mach-s3c2412/Kconfig"
894 source "arch/arm/mach-s3c2440/Kconfig"
895 source "arch/arm/mach-s3c2443/Kconfig"
899 source "arch/arm/mach-s3c64xx/Kconfig"
902 source "arch/arm/mach-s5p6440/Kconfig"
904 source "arch/arm/mach-s5p6442/Kconfig"
907 source "arch/arm/mach-s5pc100/Kconfig"
910 source "arch/arm/mach-s5pv210/Kconfig"
912 source "arch/arm/mach-shmobile/Kconfig"
914 source "arch/arm/plat-stmp3xxx/Kconfig"
916 source "arch/arm/mach-u300/Kconfig"
918 source "arch/arm/mach-ux500/Kconfig"
920 source "arch/arm/mach-versatile/Kconfig"
922 source "arch/arm/mach-w90x900/Kconfig"
924 # Definitions to make life easier
930 select GENERIC_CLOCKEVENTS
939 source arch/arm/mm/Kconfig
942 bool "Enable iWMMXt support"
943 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK
944 default y if PXA27x || PXA3xx || ARCH_MMP
946 Enable support for iWMMXt context switching at run time if
947 running on a CPU that supports it.
949 # bool 'Use XScale PMU as timer source' CONFIG_XSCALE_PMU_TIMER
952 depends on CPU_XSCALE && !XSCALE_PMU_TIMER
956 depends on CPU_V6 || CPU_V7 || XSCALE_PMU
961 source "arch/arm/Kconfig-nommu"
964 config ARM_ERRATA_411920
965 bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
966 depends on CPU_V6 && !SMP
968 Invalidation of the Instruction Cache operation can
969 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
970 It does not affect the MPCore. This option enables the ARM Ltd.
971 recommended workaround.
973 config ARM_ERRATA_430973
974 bool "ARM errata: Stale prediction on replaced interworking branch"
977 This option enables the workaround for the 430973 Cortex-A8
978 (r1p0..r1p2) erratum. If a code sequence containing an ARM/Thumb
979 interworking branch is replaced with another code sequence at the
980 same virtual address, whether due to self-modifying code or virtual
981 to physical address re-mapping, Cortex-A8 does not recover from the
982 stale interworking branch prediction. This results in Cortex-A8
983 executing the new code sequence in the incorrect ARM or Thumb state.
984 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
985 and also flushes the branch target cache at every context switch.
986 Note that setting specific bits in the ACTLR register may not be
987 available in non-secure mode.
989 config ARM_ERRATA_458693
990 bool "ARM errata: Processor deadlock when a false hazard is created"
993 This option enables the workaround for the 458693 Cortex-A8 (r2p0)
994 erratum. For very specific sequences of memory operations, it is
995 possible for a hazard condition intended for a cache line to instead
996 be incorrectly associated with a different cache line. This false
997 hazard might then cause a processor deadlock. The workaround enables
998 the L1 caching of the NEON accesses and disables the PLD instruction
999 in the ACTLR register. Note that setting specific bits in the ACTLR
1000 register may not be available in non-secure mode.
1002 config ARM_ERRATA_460075
1003 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
1006 This option enables the workaround for the 460075 Cortex-A8 (r2p0)
1007 erratum. Any asynchronous access to the L2 cache may encounter a
1008 situation in which recent store transactions to the L2 cache are lost
1009 and overwritten with stale memory contents from external memory. The
1010 workaround disables the write-allocate mode for the L2 cache via the
1011 ACTLR register. Note that setting specific bits in the ACTLR register
1012 may not be available in non-secure mode.
1014 config PL310_ERRATA_588369
1015 bool "Clean & Invalidate maintenance operations do not invalidate clean lines"
1016 depends on CACHE_L2X0 && ARCH_OMAP4
1018 The PL310 L2 cache controller implements three types of Clean &
1019 Invalidate maintenance operations: by Physical Address
1020 (offset 0x7F0), by Index/Way (0x7F8) and by Way (0x7FC).
1021 They are architecturally defined to behave as the execution of a
1022 clean operation followed immediately by an invalidate operation,
1023 both performing to the same memory location. This functionality
1024 is not correctly implemented in PL310 as clean lines are not
1025 invalidated as a result of these operations. Note that this errata
1026 uses Texas Instrument's secure monitor api.
1029 source "arch/arm/common/Kconfig"
1031 config FORCE_MAX_ZONEORDER
1044 Find out whether you have ISA slots on your motherboard. ISA is the
1045 name of a bus system, i.e. the way the CPU talks to the other stuff
1046 inside your box. Other bus systems are PCI, EISA, MicroChannel
1047 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1048 newer boards don't support it. If you have ISA, say Y, otherwise N.
1050 # Select ISA DMA controller support
1055 # Select ISA DMA interface
1060 bool "PCI support" if ARCH_INTEGRATOR_AP || ARCH_VERSATILE_PB || ARCH_IXP4XX || ARCH_KS8695 || MACH_ARMCORE
1062 Find out whether you have a PCI motherboard. PCI is the name of a
1063 bus system, i.e. the way the CPU talks to the other stuff inside
1064 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1065 VESA. If you have PCI, say Y, otherwise N.
1070 # Select the host bridge type
1071 config PCI_HOST_VIA82C505
1073 depends on PCI && ARCH_SHARK
1076 config PCI_HOST_ITE8152
1078 depends on PCI && MACH_ARMCORE
1082 source "drivers/pci/Kconfig"
1084 source "drivers/pcmcia/Kconfig"
1088 menu "Kernel Features"
1090 source "kernel/time/Kconfig"
1093 bool "Symmetric Multi-Processing (EXPERIMENTAL)"
1094 depends on EXPERIMENTAL && (REALVIEW_EB_ARM11MP || REALVIEW_EB_A9MP ||\
1095 MACH_REALVIEW_PB11MP || MACH_REALVIEW_PBX || ARCH_OMAP4 || ARCH_U8500)
1096 depends on GENERIC_CLOCKEVENTS
1097 select USE_GENERIC_SMP_HELPERS
1098 select HAVE_ARM_SCU if (ARCH_REALVIEW || ARCH_OMAP4 || ARCH_U8500)
1100 This enables support for systems with more than one CPU. If you have
1101 a system with only one CPU, like most personal computers, say N. If
1102 you have a system with more than one CPU, say Y.
1104 If you say N here, the kernel will run on single and multiprocessor
1105 machines, but will use only one CPU of a multiprocessor machine. If
1106 you say Y here, the kernel will run on many, but not all, single
1107 processor machines. On a single processor machine, the kernel will
1108 run faster if you say N here.
1110 See also <file:Documentation/i386/IO-APIC.txt>,
1111 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
1112 <http://www.linuxdoc.org/docs.html#howto>.
1114 If you don't know what to do here, say N.
1120 This option enables support for the ARM system coherency unit
1126 This options enables support for the ARM timer and watchdog unit
1129 prompt "Memory split"
1132 Select the desired split between kernel and user memory.
1134 If you are not absolutely sure what you are doing, leave this
1138 bool "3G/1G user/kernel split"
1140 bool "2G/2G user/kernel split"
1142 bool "1G/3G user/kernel split"
1147 default 0x40000000 if VMSPLIT_1G
1148 default 0x80000000 if VMSPLIT_2G
1152 int "Maximum number of CPUs (2-32)"
1158 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
1159 depends on SMP && HOTPLUG && EXPERIMENTAL
1161 Say Y here to experiment with turning CPUs off and on. CPUs
1162 can be controlled through /sys/devices/system/cpu.
1165 bool "Use local timer interrupts"
1166 depends on SMP && (REALVIEW_EB_ARM11MP || MACH_REALVIEW_PB11MP || \
1167 REALVIEW_EB_A9MP || MACH_REALVIEW_PBX || ARCH_OMAP4 || ARCH_U8500)
1169 select HAVE_ARM_TWD if (ARCH_REALVIEW || ARCH_OMAP4 || ARCH_U8500)
1171 Enable support for local timers on SMP platforms, rather then the
1172 legacy IPI broadcast method. Local timers allows the system
1173 accounting to be spread across the timer interval, preventing a
1174 "thundering herd" at every timer tick.
1176 source kernel/Kconfig.preempt
1180 default 128 if ARCH_L7200
1181 default 200 if ARCH_EBSA110 || ARCH_S3C2410 || ARCH_S5P6440 || ARCH_S5P6442 || ARCH_S5PV210
1182 default OMAP_32K_TIMER_HZ if ARCH_OMAP && OMAP_32K_TIMER
1183 default AT91_TIMER_HZ if ARCH_AT91
1186 config THUMB2_KERNEL
1187 bool "Compile the kernel in Thumb-2 mode"
1188 depends on CPU_V7 && EXPERIMENTAL
1190 select ARM_ASM_UNIFIED
1192 By enabling this option, the kernel will be compiled in
1193 Thumb-2 mode. A compiler/assembler that understand the unified
1194 ARM-Thumb syntax is needed.
1198 config ARM_ASM_UNIFIED
1202 bool "Use the ARM EABI to compile the kernel"
1204 This option allows for the kernel to be compiled using the latest
1205 ARM ABI (aka EABI). This is only useful if you are using a user
1206 space environment that is also compiled with EABI.
1208 Since there are major incompatibilities between the legacy ABI and
1209 EABI, especially with regard to structure member alignment, this
1210 option also changes the kernel syscall calling convention to
1211 disambiguate both ABIs and allow for backward compatibility support
1212 (selected with CONFIG_OABI_COMPAT).
1214 To use this you need GCC version 4.0.0 or later.
1217 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1218 depends on AEABI && EXPERIMENTAL
1221 This option preserves the old syscall interface along with the
1222 new (ARM EABI) one. It also provides a compatibility layer to
1223 intercept syscalls that have structure arguments which layout
1224 in memory differs between the legacy ABI and the new ARM EABI
1225 (only for non "thumb" binaries). This option adds a tiny
1226 overhead to all syscalls and produces a slightly larger kernel.
1227 If you know you'll be using only pure EABI user space then you
1228 can say N here. If this option is not selected and you attempt
1229 to execute a legacy ABI binary then the result will be
1230 UNPREDICTABLE (in fact it can be predicted that it won't work
1231 at all). If in doubt say Y.
1233 config ARCH_HAS_HOLES_MEMORYMODEL
1236 # Discontigmem is deprecated
1237 config ARCH_DISCONTIGMEM_ENABLE
1240 config ARCH_SPARSEMEM_ENABLE
1243 config ARCH_SPARSEMEM_DEFAULT
1244 def_bool ARCH_SPARSEMEM_ENABLE
1246 config ARCH_SELECT_MEMORY_MODEL
1247 def_bool ARCH_DISCONTIGMEM_ENABLE && ARCH_SPARSEMEM_ENABLE
1251 default "4" if ARCH_LH7A40X
1253 depends on NEED_MULTIPLE_NODES
1256 bool "High Memory Support (EXPERIMENTAL)"
1257 depends on MMU && EXPERIMENTAL
1259 The address space of ARM processors is only 4 Gigabytes large
1260 and it has to accommodate user address space, kernel address
1261 space as well as some memory mapped IO. That means that, if you
1262 have a large amount of physical memory and/or IO, not all of the
1263 memory can be "permanently mapped" by the kernel. The physical
1264 memory that is not permanently mapped is called "high memory".
1266 Depending on the selected kernel/user memory split, minimum
1267 vmalloc space and actual amount of RAM, you may not need this
1268 option which should result in a slightly faster kernel.
1273 bool "Allocate 2nd-level pagetables from highmem"
1275 depends on !OUTER_CACHE
1277 config HW_PERF_EVENTS
1278 bool "Enable hardware performance counter support for perf events"
1279 depends on PERF_EVENTS && CPU_HAS_PMU && (CPU_V6 || CPU_V7)
1282 Enable hardware performance counter support for perf events. If
1283 disabled, perf events will use software events only.
1288 bool "Timer and CPU usage LEDs"
1289 depends on ARCH_CDB89712 || ARCH_EBSA110 || \
1290 ARCH_EBSA285 || ARCH_INTEGRATOR || \
1291 ARCH_LUBBOCK || MACH_MAINSTONE || ARCH_NETWINDER || \
1292 ARCH_OMAP || ARCH_P720T || ARCH_PXA_IDP || \
1293 ARCH_SA1100 || ARCH_SHARK || ARCH_VERSATILE || \
1294 ARCH_AT91 || ARCH_DAVINCI || \
1295 ARCH_KS8695 || MACH_RD88F5182 || ARCH_REALVIEW
1297 If you say Y here, the LEDs on your machine will be used
1298 to provide useful information about your current system status.
1300 If you are compiling a kernel for a NetWinder or EBSA-285, you will
1301 be able to select which LEDs are active using the options below. If
1302 you are compiling a kernel for the EBSA-110 or the LART however, the
1303 red LED will simply flash regularly to indicate that the system is
1304 still functional. It is safe to say Y here if you have a CATS
1305 system, but the driver will do nothing.
1308 bool "Timer LED" if (!ARCH_CDB89712 && !ARCH_OMAP) || \
1309 OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1310 || MACH_OMAP_PERSEUS2
1312 depends on !GENERIC_CLOCKEVENTS
1313 default y if ARCH_EBSA110
1315 If you say Y here, one of the system LEDs (the green one on the
1316 NetWinder, the amber one on the EBSA285, or the red one on the LART)
1317 will flash regularly to indicate that the system is still
1318 operational. This is mainly useful to kernel hackers who are
1319 debugging unstable kernels.
1321 The LART uses the same LED for both Timer LED and CPU usage LED
1322 functions. You may choose to use both, but the Timer LED function
1323 will overrule the CPU usage LED.
1326 bool "CPU usage LED" if (!ARCH_CDB89712 && !ARCH_EBSA110 && \
1328 || OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1329 || MACH_OMAP_PERSEUS2
1332 If you say Y here, the red LED will be used to give a good real
1333 time indication of CPU usage, by lighting whenever the idle task
1334 is not currently executing.
1336 The LART uses the same LED for both Timer LED and CPU usage LED
1337 functions. You may choose to use both, but the Timer LED function
1338 will overrule the CPU usage LED.
1340 config ALIGNMENT_TRAP
1342 depends on CPU_CP15_MMU
1343 default y if !ARCH_EBSA110
1344 select HAVE_PROC_CPU if PROC_FS
1346 ARM processors cannot fetch/store information which is not
1347 naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1348 address divisible by 4. On 32-bit ARM processors, these non-aligned
1349 fetch/store instructions will be emulated in software if you say
1350 here, which has a severe performance impact. This is necessary for
1351 correct operation of some network protocols. With an IP-only
1352 configuration it is safe to say N, otherwise say Y.
1354 config UACCESS_WITH_MEMCPY
1355 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user() (EXPERIMENTAL)"
1356 depends on MMU && EXPERIMENTAL
1357 default y if CPU_FEROCEON
1359 Implement faster copy_to_user and clear_user methods for CPU
1360 cores where a 8-word STM instruction give significantly higher
1361 memory write throughput than a sequence of individual 32bit stores.
1363 A possible side effect is a slight increase in scheduling latency
1364 between threads sharing the same address space if they invoke
1365 such copy operations with large buffers.
1367 However, if the CPU data cache is using a write-allocate mode,
1368 this option is unlikely to provide any performance gain.
1374 # Compressed boot loader in ROM. Yes, we really want to ask about
1375 # TEXT and BSS so we preserve their values in the config files.
1376 config ZBOOT_ROM_TEXT
1377 hex "Compressed ROM boot loader base address"
1380 The physical address at which the ROM-able zImage is to be
1381 placed in the target. Platforms which normally make use of
1382 ROM-able zImage formats normally set this to a suitable
1383 value in their defconfig file.
1385 If ZBOOT_ROM is not enabled, this has no effect.
1387 config ZBOOT_ROM_BSS
1388 hex "Compressed ROM boot loader BSS address"
1391 The base address of an area of read/write memory in the target
1392 for the ROM-able zImage which must be available while the
1393 decompressor is running. It must be large enough to hold the
1394 entire decompressed kernel plus an additional 128 KiB.
1395 Platforms which normally make use of ROM-able zImage formats
1396 normally set this to a suitable value in their defconfig file.
1398 If ZBOOT_ROM is not enabled, this has no effect.
1401 bool "Compressed boot loader in ROM/flash"
1402 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1404 Say Y here if you intend to execute your compressed kernel image
1405 (zImage) directly from ROM or flash. If unsure, say N.
1408 string "Default kernel command string"
1411 On some architectures (EBSA110 and CATS), there is currently no way
1412 for the boot loader to pass arguments to the kernel. For these
1413 architectures, you should supply some command-line options at build
1414 time by entering them here. As a minimum, you should specify the
1415 memory size and the root device (e.g., mem=64M root=/dev/nfs).
1418 bool "Kernel Execute-In-Place from ROM"
1419 depends on !ZBOOT_ROM
1421 Execute-In-Place allows the kernel to run from non-volatile storage
1422 directly addressable by the CPU, such as NOR flash. This saves RAM
1423 space since the text section of the kernel is not loaded from flash
1424 to RAM. Read-write sections, such as the data section and stack,
1425 are still copied to RAM. The XIP kernel is not compressed since
1426 it has to run directly from flash, so it will take more space to
1427 store it. The flash address used to link the kernel object files,
1428 and for storing it, is configuration dependent. Therefore, if you
1429 say Y here, you must know the proper physical address where to
1430 store the kernel image depending on your own flash memory usage.
1432 Also note that the make target becomes "make xipImage" rather than
1433 "make zImage" or "make Image". The final kernel binary to put in
1434 ROM memory will be arch/arm/boot/xipImage.
1438 config XIP_PHYS_ADDR
1439 hex "XIP Kernel Physical Location"
1440 depends on XIP_KERNEL
1441 default "0x00080000"
1443 This is the physical address in your flash memory the kernel will
1444 be linked for and stored to. This address is dependent on your
1448 bool "Kexec system call (EXPERIMENTAL)"
1449 depends on EXPERIMENTAL
1451 kexec is a system call that implements the ability to shutdown your
1452 current kernel, and to start another kernel. It is like a reboot
1453 but it is independent of the system firmware. And like a reboot
1454 you can start any kernel with it, not just Linux.
1456 It is an ongoing process to be certain the hardware in a machine
1457 is properly shutdown, so do not be surprised if this code does not
1458 initially work for you. It may help to enable device hotplugging
1462 bool "Export atags in procfs"
1466 Should the atags used to boot the kernel be exported in an "atags"
1467 file in procfs. Useful with kexec.
1471 menu "CPU Power Management"
1475 source "drivers/cpufreq/Kconfig"
1477 config CPU_FREQ_SA1100
1480 config CPU_FREQ_SA1110
1483 config CPU_FREQ_INTEGRATOR
1484 tristate "CPUfreq driver for ARM Integrator CPUs"
1485 depends on ARCH_INTEGRATOR && CPU_FREQ
1488 This enables the CPUfreq driver for ARM Integrator CPUs.
1490 For details, take a look at <file:Documentation/cpu-freq>.
1496 depends on CPU_FREQ && ARCH_PXA && PXA25x
1498 select CPU_FREQ_DEFAULT_GOV_USERSPACE
1500 config CPU_FREQ_S3C64XX
1501 bool "CPUfreq support for Samsung S3C64XX CPUs"
1502 depends on CPU_FREQ && CPU_S3C6410
1507 Internal configuration node for common cpufreq on Samsung SoC
1509 config CPU_FREQ_S3C24XX
1510 bool "CPUfreq driver for Samsung S3C24XX series CPUs"
1511 depends on ARCH_S3C2410 && CPU_FREQ && EXPERIMENTAL
1514 This enables the CPUfreq driver for the Samsung S3C24XX family
1517 For details, take a look at <file:Documentation/cpu-freq>.
1521 config CPU_FREQ_S3C24XX_PLL
1522 bool "Support CPUfreq changing of PLL frequency"
1523 depends on CPU_FREQ_S3C24XX && EXPERIMENTAL
1525 Compile in support for changing the PLL frequency from the
1526 S3C24XX series CPUfreq driver. The PLL takes time to settle
1527 after a frequency change, so by default it is not enabled.
1529 This also means that the PLL tables for the selected CPU(s) will
1530 be built which may increase the size of the kernel image.
1532 config CPU_FREQ_S3C24XX_DEBUG
1533 bool "Debug CPUfreq Samsung driver core"
1534 depends on CPU_FREQ_S3C24XX
1536 Enable s3c_freq_dbg for the Samsung S3C CPUfreq core
1538 config CPU_FREQ_S3C24XX_IODEBUG
1539 bool "Debug CPUfreq Samsung driver IO timing"
1540 depends on CPU_FREQ_S3C24XX
1542 Enable s3c_freq_iodbg for the Samsung S3C CPUfreq core
1544 config CPU_FREQ_S3C24XX_DEBUGFS
1545 bool "Export debugfs for CPUFreq"
1546 depends on CPU_FREQ_S3C24XX && DEBUG_FS
1548 Export status information via debugfs.
1552 source "drivers/cpuidle/Kconfig"
1556 menu "Floating point emulation"
1558 comment "At least one emulation must be selected"
1561 bool "NWFPE math emulation"
1562 depends on !AEABI || OABI_COMPAT
1564 Say Y to include the NWFPE floating point emulator in the kernel.
1565 This is necessary to run most binaries. Linux does not currently
1566 support floating point hardware so you need to say Y here even if
1567 your machine has an FPA or floating point co-processor podule.
1569 You may say N here if you are going to load the Acorn FPEmulator
1570 early in the bootup.
1573 bool "Support extended precision"
1574 depends on FPE_NWFPE
1576 Say Y to include 80-bit support in the kernel floating-point
1577 emulator. Otherwise, only 32 and 64-bit support is compiled in.
1578 Note that gcc does not generate 80-bit operations by default,
1579 so in most cases this option only enlarges the size of the
1580 floating point emulator without any good reason.
1582 You almost surely want to say N here.
1585 bool "FastFPE math emulation (EXPERIMENTAL)"
1586 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3 && EXPERIMENTAL
1588 Say Y here to include the FAST floating point emulator in the kernel.
1589 This is an experimental much faster emulator which now also has full
1590 precision for the mantissa. It does not support any exceptions.
1591 It is very simple, and approximately 3-6 times faster than NWFPE.
1593 It should be sufficient for most programs. It may be not suitable
1594 for scientific calculations, but you have to check this for yourself.
1595 If you do not feel you need a faster FP emulation you should better
1599 bool "VFP-format floating point maths"
1600 depends on CPU_V6 || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
1602 Say Y to include VFP support code in the kernel. This is needed
1603 if your hardware includes a VFP unit.
1605 Please see <file:Documentation/arm/VFP/release-notes.txt> for
1606 release notes and additional status information.
1608 Say N if your target does not have VFP hardware.
1616 bool "Advanced SIMD (NEON) Extension support"
1617 depends on VFPv3 && CPU_V7
1619 Say Y to include support code for NEON, the ARMv7 Advanced SIMD
1624 menu "Userspace binary formats"
1626 source "fs/Kconfig.binfmt"
1629 tristate "RISC OS personality"
1632 Say Y here to include the kernel code necessary if you want to run
1633 Acorn RISC OS/Arthur binaries under Linux. This code is still very
1634 experimental; if this sounds frightening, say N and sleep in peace.
1635 You can also say M here to compile this support as a module (which
1636 will be called arthur).
1640 menu "Power management options"
1642 source "kernel/power/Kconfig"
1644 config ARCH_SUSPEND_POSSIBLE
1649 source "net/Kconfig"
1651 source "drivers/Kconfig"
1655 source "arch/arm/Kconfig.debug"
1657 source "security/Kconfig"
1659 source "crypto/Kconfig"
1661 source "lib/Kconfig"