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
256 select GPIO_PL061 if GPIOLIB
258 This enables support for ARM Ltd RealView boards.
260 config ARCH_VERSATILE
261 bool "ARM Ltd. Versatile family"
268 select GENERIC_CLOCKEVENTS
269 select ARCH_WANT_OPTIONAL_GPIOLIB
271 This enables support for ARM Ltd Versatile board.
276 select ARCH_REQUIRE_GPIOLIB
279 This enables support for systems based on the Atmel AT91RM9200,
280 AT91SAM9 and AT91CAP9 processors.
283 bool "Broadcom BCMRING"
289 select GENERIC_CLOCKEVENTS
290 select ARCH_WANT_OPTIONAL_GPIOLIB
292 Support for Broadcom's BCMRing platform.
295 bool "Cirrus Logic CLPS711x/EP721x-based"
298 Support for Cirrus Logic 711x/721x based boards.
301 bool "Cavium Networks CNS3XXX family"
304 select GENERIC_CLOCKEVENTS
307 Support for Cavium Networks CNS3XXX platform.
310 bool "Cortina Systems Gemini"
313 select ARCH_REQUIRE_GPIOLIB
315 Support for the Cortina Systems Gemini family SoCs
323 This is an evaluation board for the StrongARM processor available
324 from Digital. It has limited hardware on-board, including an
325 Ethernet interface, two PCMCIA sockets, two serial ports and a
336 select ARCH_REQUIRE_GPIOLIB
337 select ARCH_HAS_HOLES_MEMORYMODEL
339 This enables support for the Cirrus EP93xx series of CPUs.
341 config ARCH_FOOTBRIDGE
346 Support for systems based on the DC21285 companion chip
347 ("FootBridge"), such as the Simtec CATS and the Rebel NetWinder.
350 bool "Freescale MXC/iMX-based"
352 select GENERIC_CLOCKEVENTS
353 select ARCH_REQUIRE_GPIOLIB
357 Support for Freescale MXC/iMX-based family of processors
360 bool "Freescale STMP3xxx"
364 select ARCH_REQUIRE_GPIOLIB
366 select GENERIC_CLOCKEVENTS
368 select USB_ARCH_HAS_EHCI
370 Support for systems based on the Freescale 3xxx CPUs.
373 bool "Hilscher NetX based"
376 select GENERIC_CLOCKEVENTS
379 This enables support for systems based on the Hilscher NetX Soc
382 bool "Hynix HMS720x-based"
386 This enables support for systems based on the Hynix HMS720x
394 select ARCH_SUPPORTS_MSI
397 Support for Intel's IOP13XX (XScale) family of processors.
406 select ARCH_REQUIRE_GPIOLIB
408 Support for Intel's 80219 and IOP32X (XScale) family of
418 select ARCH_REQUIRE_GPIOLIB
420 Support for Intel's IOP33X (XScale) family of processors.
428 Support for Intel's IXP23xx (XScale) family of processors.
431 bool "IXP2400/2800-based"
436 Support for Intel's IXP2400/2800 (XScale) family of processors.
444 select GENERIC_CLOCKEVENTS
445 select DMABOUNCE if PCI
447 Support for Intel's IXP4XX (XScale) family of processors.
454 Say Y here if you intend to run this kernel on a LinkUp Systems
455 L7200 Software Development Board which uses an ARM720T processor.
456 Information on this board can be obtained at:
458 <http://www.linkupsys.com/>
460 If you have any questions or comments about the Linux kernel port
461 to this board, send e-mail to <sjhill@cotw.com>.
467 select ARCH_REQUIRE_GPIOLIB
469 select GENERIC_CLOCKEVENTS
472 Support for the Marvell Dove SoC 88AP510
475 bool "Marvell Kirkwood"
479 select ARCH_REQUIRE_GPIOLIB
481 select GENERIC_CLOCKEVENTS
484 Support for the following Marvell Kirkwood series SoCs:
485 88F6180, 88F6192 and 88F6281.
488 bool "Marvell Loki (88RC8480)"
491 select GENERIC_CLOCKEVENTS
494 Support for the Marvell Loki (88RC8480) SoC.
497 bool "Marvell MV78xx0"
501 select ARCH_REQUIRE_GPIOLIB
503 select GENERIC_CLOCKEVENTS
506 Support for the following Marvell MV78xx0 series SoCs:
515 select ARCH_REQUIRE_GPIOLIB
517 select GENERIC_CLOCKEVENTS
520 Support for the following Marvell Orion 5x series SoCs:
521 Orion-1 (5181), Orion-VoIP (5181L), Orion-NAS (5182),
522 Orion-2 (5281), Orion-1-90 (6183).
525 bool "Marvell PXA168/910/MMP2"
528 select ARCH_REQUIRE_GPIOLIB
532 select GENERIC_CLOCKEVENTS
536 Support for Marvell's PXA168/PXA910(MMP) and MMP2 processor line.
539 bool "Micrel/Kendin KS8695"
542 select ARCH_REQUIRE_GPIOLIB
544 Support for Micrel/Kendin KS8695 "Centaur" (ARM922T) based
545 System-on-Chip devices.
548 bool "NetSilicon NS9xxx"
552 select GENERIC_CLOCKEVENTS
555 Say Y here if you intend to run this kernel on a NetSilicon NS9xxx
558 <http://www.digi.com/products/microprocessors/index.jsp>
561 bool "Nuvoton W90X900 CPU"
563 select ARCH_REQUIRE_GPIOLIB
568 select GENERIC_CLOCKEVENTS
570 Support for Nuvoton (Winbond logic dept.) ARM9 processor,
571 At present, the w90x900 has been renamed nuc900, regarding
572 the ARM series product line, you can login the following
573 link address to know more.
575 <http://www.nuvoton.com/hq/enu/ProductAndSales/ProductLines/
576 ConsumerElectronicsIC/ARMMicrocontroller/ARMMicrocontroller>
579 bool "Nuvoton NUC93X CPU"
584 Support for Nuvoton (Winbond logic dept.) NUC93X MCU,The NUC93X is a
585 low-power and high performance MPEG-4/JPEG multimedia controller chip.
588 bool "Philips Nexperia PNX4008 Mobile"
593 This enables support for Philips PNX4008 mobile platform.
596 bool "PXA2xx/PXA3xx-based"
599 select ARCH_HAS_CPUFREQ
603 select ARCH_REQUIRE_GPIOLIB
605 select GENERIC_CLOCKEVENTS
609 Support for Intel/Marvell's PXA2xx/PXA3xx processor line.
615 select GENERIC_CLOCKEVENTS
617 Support for Qualcomm MSM7K based systems. This runs on the ARM11
618 apps processor of the MSM7K and depends on a shared memory
619 interface to the ARM9 modem processor which runs the baseband stack
620 and controls some vital subsystems (clock and power control, etc).
623 bool "Renesas SH-Mobile"
625 Support for Renesas's SH-Mobile ARM platforms
632 select ARCH_MAY_HAVE_PC_FDC
633 select HAVE_PATA_PLATFORM
636 select ARCH_SPARSEMEM_ENABLE
638 On the Acorn Risc-PC, Linux can support the internal IDE disk and
639 CD-ROM interface, serial and parallel port, and the floppy drive.
645 select ARCH_SPARSEMEM_ENABLE
647 select ARCH_HAS_CPUFREQ
651 select GENERIC_CLOCKEVENTS
654 select ARCH_REQUIRE_GPIOLIB
656 Support for StrongARM 11x0 based boards.
659 bool "Samsung S3C2410, S3C2412, S3C2413, S3C2440, S3C2442, S3C2443"
661 select ARCH_HAS_CPUFREQ
664 Samsung S3C2410X CPU based systems, such as the Simtec Electronics
665 BAST (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or
666 the Samsung SMDK2410 development board (and derivatives).
669 bool "Samsung S3C64XX"
676 select ARCH_HAS_CPUFREQ
677 select ARCH_REQUIRE_GPIOLIB
678 select SAMSUNG_CLKSRC
679 select SAMSUNG_IRQ_VIC_TIMER
680 select SAMSUNG_IRQ_UART
681 select S3C_GPIO_TRACK
682 select S3C_GPIO_PULL_UPDOWN
683 select S3C_GPIO_CFG_S3C24XX
684 select S3C_GPIO_CFG_S3C64XX
686 select USB_ARCH_HAS_OHCI
687 select SAMSUNG_GPIOLIB_4BIT
689 Samsung S3C64XX series based systems
692 bool "Samsung S5P6440"
697 Samsung S5P6440 CPU based systems
700 bool "Samsung S5P6442"
705 Samsung S5P6442 CPU based systems
708 bool "Samsung S5PC1XX"
712 select ARM_L1_CACHE_SHIFT_6
714 Samsung S5PC1XX series based systems
717 bool "Samsung S5PV210/S5PC110"
721 select ARM_L1_CACHE_SHIFT_6
723 Samsung S5PV210/S5PC110 series based systems
733 Support for the StrongARM based Digital DNARD machine, also known
734 as "Shark" (<http://www.shark-linux.de/shark.html>).
739 select ARCH_DISCONTIGMEM_ENABLE if !LH7A40X_CONTIGMEM
740 select ARCH_SPARSEMEM_ENABLE if !LH7A40X_CONTIGMEM
742 Say Y here for systems based on one of the Sharp LH7A40X
743 System on a Chip processors. These CPUs include an ARM922T
744 core with a wide array of integrated devices for
745 hand-held and low-power applications.
748 bool "ST-Ericsson U300 Series"
755 select GENERIC_CLOCKEVENTS
760 Support for ST-Ericsson U300 series mobile platforms.
763 bool "ST-Ericsson U8500 Series"
767 select GENERIC_CLOCKEVENTS
770 Support for ST-Ericsson's Ux500 architecture
773 bool "STMicroelectronics Nomadik"
780 select GENERIC_CLOCKEVENTS
782 select ARCH_REQUIRE_GPIOLIB
784 Support for the Nomadik platform by ST-Ericsson
790 select GENERIC_CLOCKEVENTS
792 select ARCH_REQUIRE_GPIOLIB
797 select GENERIC_ALLOCATOR
798 select ARCH_HAS_HOLES_MEMORYMODEL
800 Support for TI's DaVinci platform.
806 select ARCH_REQUIRE_GPIOLIB
807 select ARCH_HAS_CPUFREQ
809 select GENERIC_CLOCKEVENTS
810 select ARCH_HAS_HOLES_MEMORYMODEL
812 Support for TI's OMAP platform (OMAP1 and OMAP2).
817 # This is sorted alphabetically by mach-* pathname. However, plat-*
818 # Kconfigs may be included either alphabetically (according to the
819 # plat- suffix) or along side the corresponding mach-* source.
821 source "arch/arm/mach-aaec2000/Kconfig"
823 source "arch/arm/mach-at91/Kconfig"
825 source "arch/arm/mach-bcmring/Kconfig"
827 source "arch/arm/mach-clps711x/Kconfig"
829 source "arch/arm/mach-cns3xxx/Kconfig"
831 source "arch/arm/mach-davinci/Kconfig"
833 source "arch/arm/mach-dove/Kconfig"
835 source "arch/arm/mach-ep93xx/Kconfig"
837 source "arch/arm/mach-footbridge/Kconfig"
839 source "arch/arm/mach-gemini/Kconfig"
841 source "arch/arm/mach-h720x/Kconfig"
843 source "arch/arm/mach-integrator/Kconfig"
845 source "arch/arm/mach-iop32x/Kconfig"
847 source "arch/arm/mach-iop33x/Kconfig"
849 source "arch/arm/mach-iop13xx/Kconfig"
851 source "arch/arm/mach-ixp4xx/Kconfig"
853 source "arch/arm/mach-ixp2000/Kconfig"
855 source "arch/arm/mach-ixp23xx/Kconfig"
857 source "arch/arm/mach-kirkwood/Kconfig"
859 source "arch/arm/mach-ks8695/Kconfig"
861 source "arch/arm/mach-lh7a40x/Kconfig"
863 source "arch/arm/mach-loki/Kconfig"
865 source "arch/arm/mach-msm/Kconfig"
867 source "arch/arm/mach-mv78xx0/Kconfig"
869 source "arch/arm/plat-mxc/Kconfig"
871 source "arch/arm/mach-netx/Kconfig"
873 source "arch/arm/mach-nomadik/Kconfig"
874 source "arch/arm/plat-nomadik/Kconfig"
876 source "arch/arm/mach-ns9xxx/Kconfig"
878 source "arch/arm/mach-nuc93x/Kconfig"
880 source "arch/arm/plat-omap/Kconfig"
882 source "arch/arm/mach-omap1/Kconfig"
884 source "arch/arm/mach-omap2/Kconfig"
886 source "arch/arm/mach-orion5x/Kconfig"
888 source "arch/arm/mach-pxa/Kconfig"
889 source "arch/arm/plat-pxa/Kconfig"
891 source "arch/arm/mach-mmp/Kconfig"
893 source "arch/arm/mach-realview/Kconfig"
895 source "arch/arm/mach-sa1100/Kconfig"
897 source "arch/arm/plat-samsung/Kconfig"
898 source "arch/arm/plat-s3c24xx/Kconfig"
899 source "arch/arm/plat-s5p/Kconfig"
900 source "arch/arm/plat-s5pc1xx/Kconfig"
903 source "arch/arm/mach-s3c2400/Kconfig"
904 source "arch/arm/mach-s3c2410/Kconfig"
905 source "arch/arm/mach-s3c2412/Kconfig"
906 source "arch/arm/mach-s3c2440/Kconfig"
907 source "arch/arm/mach-s3c2443/Kconfig"
911 source "arch/arm/mach-s3c64xx/Kconfig"
914 source "arch/arm/mach-s5p6440/Kconfig"
916 source "arch/arm/mach-s5p6442/Kconfig"
919 source "arch/arm/mach-s5pc100/Kconfig"
922 source "arch/arm/mach-s5pv210/Kconfig"
924 source "arch/arm/mach-shmobile/Kconfig"
926 source "arch/arm/plat-stmp3xxx/Kconfig"
928 source "arch/arm/mach-u300/Kconfig"
930 source "arch/arm/mach-ux500/Kconfig"
932 source "arch/arm/mach-versatile/Kconfig"
934 source "arch/arm/mach-w90x900/Kconfig"
936 # Definitions to make life easier
942 select GENERIC_CLOCKEVENTS
951 source arch/arm/mm/Kconfig
954 bool "Enable iWMMXt support"
955 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK
956 default y if PXA27x || PXA3xx || ARCH_MMP
958 Enable support for iWMMXt context switching at run time if
959 running on a CPU that supports it.
961 # bool 'Use XScale PMU as timer source' CONFIG_XSCALE_PMU_TIMER
964 depends on CPU_XSCALE && !XSCALE_PMU_TIMER
968 depends on CPU_V6 || CPU_V7 || XSCALE_PMU
973 source "arch/arm/Kconfig-nommu"
976 config ARM_ERRATA_411920
977 bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
978 depends on CPU_V6 && !SMP
980 Invalidation of the Instruction Cache operation can
981 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
982 It does not affect the MPCore. This option enables the ARM Ltd.
983 recommended workaround.
985 config ARM_ERRATA_430973
986 bool "ARM errata: Stale prediction on replaced interworking branch"
989 This option enables the workaround for the 430973 Cortex-A8
990 (r1p0..r1p2) erratum. If a code sequence containing an ARM/Thumb
991 interworking branch is replaced with another code sequence at the
992 same virtual address, whether due to self-modifying code or virtual
993 to physical address re-mapping, Cortex-A8 does not recover from the
994 stale interworking branch prediction. This results in Cortex-A8
995 executing the new code sequence in the incorrect ARM or Thumb state.
996 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
997 and also flushes the branch target cache at every context switch.
998 Note that setting specific bits in the ACTLR register may not be
999 available in non-secure mode.
1001 config ARM_ERRATA_458693
1002 bool "ARM errata: Processor deadlock when a false hazard is created"
1005 This option enables the workaround for the 458693 Cortex-A8 (r2p0)
1006 erratum. For very specific sequences of memory operations, it is
1007 possible for a hazard condition intended for a cache line to instead
1008 be incorrectly associated with a different cache line. This false
1009 hazard might then cause a processor deadlock. The workaround enables
1010 the L1 caching of the NEON accesses and disables the PLD instruction
1011 in the ACTLR register. Note that setting specific bits in the ACTLR
1012 register may not be available in non-secure mode.
1014 config ARM_ERRATA_460075
1015 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
1018 This option enables the workaround for the 460075 Cortex-A8 (r2p0)
1019 erratum. Any asynchronous access to the L2 cache may encounter a
1020 situation in which recent store transactions to the L2 cache are lost
1021 and overwritten with stale memory contents from external memory. The
1022 workaround disables the write-allocate mode for the L2 cache via the
1023 ACTLR register. Note that setting specific bits in the ACTLR register
1024 may not be available in non-secure mode.
1026 config PL310_ERRATA_588369
1027 bool "Clean & Invalidate maintenance operations do not invalidate clean lines"
1028 depends on CACHE_L2X0 && ARCH_OMAP4
1030 The PL310 L2 cache controller implements three types of Clean &
1031 Invalidate maintenance operations: by Physical Address
1032 (offset 0x7F0), by Index/Way (0x7F8) and by Way (0x7FC).
1033 They are architecturally defined to behave as the execution of a
1034 clean operation followed immediately by an invalidate operation,
1035 both performing to the same memory location. This functionality
1036 is not correctly implemented in PL310 as clean lines are not
1037 invalidated as a result of these operations. Note that this errata
1038 uses Texas Instrument's secure monitor api.
1041 source "arch/arm/common/Kconfig"
1043 config FORCE_MAX_ZONEORDER
1056 Find out whether you have ISA slots on your motherboard. ISA is the
1057 name of a bus system, i.e. the way the CPU talks to the other stuff
1058 inside your box. Other bus systems are PCI, EISA, MicroChannel
1059 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1060 newer boards don't support it. If you have ISA, say Y, otherwise N.
1062 # Select ISA DMA controller support
1067 # Select ISA DMA interface
1072 bool "PCI support" if ARCH_INTEGRATOR_AP || ARCH_VERSATILE_PB || ARCH_IXP4XX || ARCH_KS8695 || MACH_ARMCORE
1074 Find out whether you have a PCI motherboard. PCI is the name of a
1075 bus system, i.e. the way the CPU talks to the other stuff inside
1076 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1077 VESA. If you have PCI, say Y, otherwise N.
1082 # Select the host bridge type
1083 config PCI_HOST_VIA82C505
1085 depends on PCI && ARCH_SHARK
1088 config PCI_HOST_ITE8152
1090 depends on PCI && MACH_ARMCORE
1094 source "drivers/pci/Kconfig"
1096 source "drivers/pcmcia/Kconfig"
1100 menu "Kernel Features"
1102 source "kernel/time/Kconfig"
1105 bool "Symmetric Multi-Processing (EXPERIMENTAL)"
1106 depends on EXPERIMENTAL && (REALVIEW_EB_ARM11MP || REALVIEW_EB_A9MP ||\
1107 MACH_REALVIEW_PB11MP || MACH_REALVIEW_PBX || ARCH_OMAP4 || ARCH_U8500)
1108 depends on GENERIC_CLOCKEVENTS
1109 select USE_GENERIC_SMP_HELPERS
1110 select HAVE_ARM_SCU if (ARCH_REALVIEW || ARCH_OMAP4 || ARCH_U8500)
1112 This enables support for systems with more than one CPU. If you have
1113 a system with only one CPU, like most personal computers, say N. If
1114 you have a system with more than one CPU, say Y.
1116 If you say N here, the kernel will run on single and multiprocessor
1117 machines, but will use only one CPU of a multiprocessor machine. If
1118 you say Y here, the kernel will run on many, but not all, single
1119 processor machines. On a single processor machine, the kernel will
1120 run faster if you say N here.
1122 See also <file:Documentation/i386/IO-APIC.txt>,
1123 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
1124 <http://www.linuxdoc.org/docs.html#howto>.
1126 If you don't know what to do here, say N.
1132 This option enables support for the ARM system coherency unit
1138 This options enables support for the ARM timer and watchdog unit
1141 prompt "Memory split"
1144 Select the desired split between kernel and user memory.
1146 If you are not absolutely sure what you are doing, leave this
1150 bool "3G/1G user/kernel split"
1152 bool "2G/2G user/kernel split"
1154 bool "1G/3G user/kernel split"
1159 default 0x40000000 if VMSPLIT_1G
1160 default 0x80000000 if VMSPLIT_2G
1164 int "Maximum number of CPUs (2-32)"
1170 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
1171 depends on SMP && HOTPLUG && EXPERIMENTAL
1173 Say Y here to experiment with turning CPUs off and on. CPUs
1174 can be controlled through /sys/devices/system/cpu.
1177 bool "Use local timer interrupts"
1178 depends on SMP && (REALVIEW_EB_ARM11MP || MACH_REALVIEW_PB11MP || \
1179 REALVIEW_EB_A9MP || MACH_REALVIEW_PBX || ARCH_OMAP4 || ARCH_U8500)
1181 select HAVE_ARM_TWD if (ARCH_REALVIEW || ARCH_OMAP4 || ARCH_U8500)
1183 Enable support for local timers on SMP platforms, rather then the
1184 legacy IPI broadcast method. Local timers allows the system
1185 accounting to be spread across the timer interval, preventing a
1186 "thundering herd" at every timer tick.
1188 source kernel/Kconfig.preempt
1192 default 128 if ARCH_L7200
1193 default 200 if ARCH_EBSA110 || ARCH_S3C2410 || ARCH_S5P6440 || ARCH_S5P6442 || ARCH_S5PV210
1194 default OMAP_32K_TIMER_HZ if ARCH_OMAP && OMAP_32K_TIMER
1195 default AT91_TIMER_HZ if ARCH_AT91
1198 config THUMB2_KERNEL
1199 bool "Compile the kernel in Thumb-2 mode"
1200 depends on CPU_V7 && EXPERIMENTAL
1202 select ARM_ASM_UNIFIED
1204 By enabling this option, the kernel will be compiled in
1205 Thumb-2 mode. A compiler/assembler that understand the unified
1206 ARM-Thumb syntax is needed.
1210 config ARM_ASM_UNIFIED
1214 bool "Use the ARM EABI to compile the kernel"
1216 This option allows for the kernel to be compiled using the latest
1217 ARM ABI (aka EABI). This is only useful if you are using a user
1218 space environment that is also compiled with EABI.
1220 Since there are major incompatibilities between the legacy ABI and
1221 EABI, especially with regard to structure member alignment, this
1222 option also changes the kernel syscall calling convention to
1223 disambiguate both ABIs and allow for backward compatibility support
1224 (selected with CONFIG_OABI_COMPAT).
1226 To use this you need GCC version 4.0.0 or later.
1229 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1230 depends on AEABI && EXPERIMENTAL
1233 This option preserves the old syscall interface along with the
1234 new (ARM EABI) one. It also provides a compatibility layer to
1235 intercept syscalls that have structure arguments which layout
1236 in memory differs between the legacy ABI and the new ARM EABI
1237 (only for non "thumb" binaries). This option adds a tiny
1238 overhead to all syscalls and produces a slightly larger kernel.
1239 If you know you'll be using only pure EABI user space then you
1240 can say N here. If this option is not selected and you attempt
1241 to execute a legacy ABI binary then the result will be
1242 UNPREDICTABLE (in fact it can be predicted that it won't work
1243 at all). If in doubt say Y.
1245 config ARCH_HAS_HOLES_MEMORYMODEL
1248 # Discontigmem is deprecated
1249 config ARCH_DISCONTIGMEM_ENABLE
1252 config ARCH_SPARSEMEM_ENABLE
1255 config ARCH_SPARSEMEM_DEFAULT
1256 def_bool ARCH_SPARSEMEM_ENABLE
1258 config ARCH_SELECT_MEMORY_MODEL
1259 def_bool ARCH_DISCONTIGMEM_ENABLE && ARCH_SPARSEMEM_ENABLE
1263 default "4" if ARCH_LH7A40X
1265 depends on NEED_MULTIPLE_NODES
1268 bool "High Memory Support (EXPERIMENTAL)"
1269 depends on MMU && EXPERIMENTAL
1271 The address space of ARM processors is only 4 Gigabytes large
1272 and it has to accommodate user address space, kernel address
1273 space as well as some memory mapped IO. That means that, if you
1274 have a large amount of physical memory and/or IO, not all of the
1275 memory can be "permanently mapped" by the kernel. The physical
1276 memory that is not permanently mapped is called "high memory".
1278 Depending on the selected kernel/user memory split, minimum
1279 vmalloc space and actual amount of RAM, you may not need this
1280 option which should result in a slightly faster kernel.
1285 bool "Allocate 2nd-level pagetables from highmem"
1287 depends on !OUTER_CACHE
1289 config HW_PERF_EVENTS
1290 bool "Enable hardware performance counter support for perf events"
1291 depends on PERF_EVENTS && CPU_HAS_PMU && (CPU_V6 || CPU_V7)
1294 Enable hardware performance counter support for perf events. If
1295 disabled, perf events will use software events only.
1300 bool "Timer and CPU usage LEDs"
1301 depends on ARCH_CDB89712 || ARCH_EBSA110 || \
1302 ARCH_EBSA285 || ARCH_INTEGRATOR || \
1303 ARCH_LUBBOCK || MACH_MAINSTONE || ARCH_NETWINDER || \
1304 ARCH_OMAP || ARCH_P720T || ARCH_PXA_IDP || \
1305 ARCH_SA1100 || ARCH_SHARK || ARCH_VERSATILE || \
1306 ARCH_AT91 || ARCH_DAVINCI || \
1307 ARCH_KS8695 || MACH_RD88F5182 || ARCH_REALVIEW
1309 If you say Y here, the LEDs on your machine will be used
1310 to provide useful information about your current system status.
1312 If you are compiling a kernel for a NetWinder or EBSA-285, you will
1313 be able to select which LEDs are active using the options below. If
1314 you are compiling a kernel for the EBSA-110 or the LART however, the
1315 red LED will simply flash regularly to indicate that the system is
1316 still functional. It is safe to say Y here if you have a CATS
1317 system, but the driver will do nothing.
1320 bool "Timer LED" if (!ARCH_CDB89712 && !ARCH_OMAP) || \
1321 OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1322 || MACH_OMAP_PERSEUS2
1324 depends on !GENERIC_CLOCKEVENTS
1325 default y if ARCH_EBSA110
1327 If you say Y here, one of the system LEDs (the green one on the
1328 NetWinder, the amber one on the EBSA285, or the red one on the LART)
1329 will flash regularly to indicate that the system is still
1330 operational. This is mainly useful to kernel hackers who are
1331 debugging unstable kernels.
1333 The LART uses the same LED for both Timer LED and CPU usage LED
1334 functions. You may choose to use both, but the Timer LED function
1335 will overrule the CPU usage LED.
1338 bool "CPU usage LED" if (!ARCH_CDB89712 && !ARCH_EBSA110 && \
1340 || OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1341 || MACH_OMAP_PERSEUS2
1344 If you say Y here, the red LED will be used to give a good real
1345 time indication of CPU usage, by lighting whenever the idle task
1346 is not currently executing.
1348 The LART uses the same LED for both Timer LED and CPU usage LED
1349 functions. You may choose to use both, but the Timer LED function
1350 will overrule the CPU usage LED.
1352 config ALIGNMENT_TRAP
1354 depends on CPU_CP15_MMU
1355 default y if !ARCH_EBSA110
1356 select HAVE_PROC_CPU if PROC_FS
1358 ARM processors cannot fetch/store information which is not
1359 naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1360 address divisible by 4. On 32-bit ARM processors, these non-aligned
1361 fetch/store instructions will be emulated in software if you say
1362 here, which has a severe performance impact. This is necessary for
1363 correct operation of some network protocols. With an IP-only
1364 configuration it is safe to say N, otherwise say Y.
1366 config UACCESS_WITH_MEMCPY
1367 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user() (EXPERIMENTAL)"
1368 depends on MMU && EXPERIMENTAL
1369 default y if CPU_FEROCEON
1371 Implement faster copy_to_user and clear_user methods for CPU
1372 cores where a 8-word STM instruction give significantly higher
1373 memory write throughput than a sequence of individual 32bit stores.
1375 A possible side effect is a slight increase in scheduling latency
1376 between threads sharing the same address space if they invoke
1377 such copy operations with large buffers.
1379 However, if the CPU data cache is using a write-allocate mode,
1380 this option is unlikely to provide any performance gain.
1386 # Compressed boot loader in ROM. Yes, we really want to ask about
1387 # TEXT and BSS so we preserve their values in the config files.
1388 config ZBOOT_ROM_TEXT
1389 hex "Compressed ROM boot loader base address"
1392 The physical address at which the ROM-able zImage is to be
1393 placed in the target. Platforms which normally make use of
1394 ROM-able zImage formats normally set this to a suitable
1395 value in their defconfig file.
1397 If ZBOOT_ROM is not enabled, this has no effect.
1399 config ZBOOT_ROM_BSS
1400 hex "Compressed ROM boot loader BSS address"
1403 The base address of an area of read/write memory in the target
1404 for the ROM-able zImage which must be available while the
1405 decompressor is running. It must be large enough to hold the
1406 entire decompressed kernel plus an additional 128 KiB.
1407 Platforms which normally make use of ROM-able zImage formats
1408 normally set this to a suitable value in their defconfig file.
1410 If ZBOOT_ROM is not enabled, this has no effect.
1413 bool "Compressed boot loader in ROM/flash"
1414 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1416 Say Y here if you intend to execute your compressed kernel image
1417 (zImage) directly from ROM or flash. If unsure, say N.
1420 string "Default kernel command string"
1423 On some architectures (EBSA110 and CATS), there is currently no way
1424 for the boot loader to pass arguments to the kernel. For these
1425 architectures, you should supply some command-line options at build
1426 time by entering them here. As a minimum, you should specify the
1427 memory size and the root device (e.g., mem=64M root=/dev/nfs).
1430 bool "Kernel Execute-In-Place from ROM"
1431 depends on !ZBOOT_ROM
1433 Execute-In-Place allows the kernel to run from non-volatile storage
1434 directly addressable by the CPU, such as NOR flash. This saves RAM
1435 space since the text section of the kernel is not loaded from flash
1436 to RAM. Read-write sections, such as the data section and stack,
1437 are still copied to RAM. The XIP kernel is not compressed since
1438 it has to run directly from flash, so it will take more space to
1439 store it. The flash address used to link the kernel object files,
1440 and for storing it, is configuration dependent. Therefore, if you
1441 say Y here, you must know the proper physical address where to
1442 store the kernel image depending on your own flash memory usage.
1444 Also note that the make target becomes "make xipImage" rather than
1445 "make zImage" or "make Image". The final kernel binary to put in
1446 ROM memory will be arch/arm/boot/xipImage.
1450 config XIP_PHYS_ADDR
1451 hex "XIP Kernel Physical Location"
1452 depends on XIP_KERNEL
1453 default "0x00080000"
1455 This is the physical address in your flash memory the kernel will
1456 be linked for and stored to. This address is dependent on your
1460 bool "Kexec system call (EXPERIMENTAL)"
1461 depends on EXPERIMENTAL
1463 kexec is a system call that implements the ability to shutdown your
1464 current kernel, and to start another kernel. It is like a reboot
1465 but it is independent of the system firmware. And like a reboot
1466 you can start any kernel with it, not just Linux.
1468 It is an ongoing process to be certain the hardware in a machine
1469 is properly shutdown, so do not be surprised if this code does not
1470 initially work for you. It may help to enable device hotplugging
1474 bool "Export atags in procfs"
1478 Should the atags used to boot the kernel be exported in an "atags"
1479 file in procfs. Useful with kexec.
1483 menu "CPU Power Management"
1487 source "drivers/cpufreq/Kconfig"
1489 config CPU_FREQ_SA1100
1492 config CPU_FREQ_SA1110
1495 config CPU_FREQ_INTEGRATOR
1496 tristate "CPUfreq driver for ARM Integrator CPUs"
1497 depends on ARCH_INTEGRATOR && CPU_FREQ
1500 This enables the CPUfreq driver for ARM Integrator CPUs.
1502 For details, take a look at <file:Documentation/cpu-freq>.
1508 depends on CPU_FREQ && ARCH_PXA && PXA25x
1510 select CPU_FREQ_DEFAULT_GOV_USERSPACE
1512 config CPU_FREQ_S3C64XX
1513 bool "CPUfreq support for Samsung S3C64XX CPUs"
1514 depends on CPU_FREQ && CPU_S3C6410
1519 Internal configuration node for common cpufreq on Samsung SoC
1521 config CPU_FREQ_S3C24XX
1522 bool "CPUfreq driver for Samsung S3C24XX series CPUs"
1523 depends on ARCH_S3C2410 && CPU_FREQ && EXPERIMENTAL
1526 This enables the CPUfreq driver for the Samsung S3C24XX family
1529 For details, take a look at <file:Documentation/cpu-freq>.
1533 config CPU_FREQ_S3C24XX_PLL
1534 bool "Support CPUfreq changing of PLL frequency"
1535 depends on CPU_FREQ_S3C24XX && EXPERIMENTAL
1537 Compile in support for changing the PLL frequency from the
1538 S3C24XX series CPUfreq driver. The PLL takes time to settle
1539 after a frequency change, so by default it is not enabled.
1541 This also means that the PLL tables for the selected CPU(s) will
1542 be built which may increase the size of the kernel image.
1544 config CPU_FREQ_S3C24XX_DEBUG
1545 bool "Debug CPUfreq Samsung driver core"
1546 depends on CPU_FREQ_S3C24XX
1548 Enable s3c_freq_dbg for the Samsung S3C CPUfreq core
1550 config CPU_FREQ_S3C24XX_IODEBUG
1551 bool "Debug CPUfreq Samsung driver IO timing"
1552 depends on CPU_FREQ_S3C24XX
1554 Enable s3c_freq_iodbg for the Samsung S3C CPUfreq core
1556 config CPU_FREQ_S3C24XX_DEBUGFS
1557 bool "Export debugfs for CPUFreq"
1558 depends on CPU_FREQ_S3C24XX && DEBUG_FS
1560 Export status information via debugfs.
1564 source "drivers/cpuidle/Kconfig"
1568 menu "Floating point emulation"
1570 comment "At least one emulation must be selected"
1573 bool "NWFPE math emulation"
1574 depends on !AEABI || OABI_COMPAT
1576 Say Y to include the NWFPE floating point emulator in the kernel.
1577 This is necessary to run most binaries. Linux does not currently
1578 support floating point hardware so you need to say Y here even if
1579 your machine has an FPA or floating point co-processor podule.
1581 You may say N here if you are going to load the Acorn FPEmulator
1582 early in the bootup.
1585 bool "Support extended precision"
1586 depends on FPE_NWFPE
1588 Say Y to include 80-bit support in the kernel floating-point
1589 emulator. Otherwise, only 32 and 64-bit support is compiled in.
1590 Note that gcc does not generate 80-bit operations by default,
1591 so in most cases this option only enlarges the size of the
1592 floating point emulator without any good reason.
1594 You almost surely want to say N here.
1597 bool "FastFPE math emulation (EXPERIMENTAL)"
1598 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3 && EXPERIMENTAL
1600 Say Y here to include the FAST floating point emulator in the kernel.
1601 This is an experimental much faster emulator which now also has full
1602 precision for the mantissa. It does not support any exceptions.
1603 It is very simple, and approximately 3-6 times faster than NWFPE.
1605 It should be sufficient for most programs. It may be not suitable
1606 for scientific calculations, but you have to check this for yourself.
1607 If you do not feel you need a faster FP emulation you should better
1611 bool "VFP-format floating point maths"
1612 depends on CPU_V6 || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
1614 Say Y to include VFP support code in the kernel. This is needed
1615 if your hardware includes a VFP unit.
1617 Please see <file:Documentation/arm/VFP/release-notes.txt> for
1618 release notes and additional status information.
1620 Say N if your target does not have VFP hardware.
1628 bool "Advanced SIMD (NEON) Extension support"
1629 depends on VFPv3 && CPU_V7
1631 Say Y to include support code for NEON, the ARMv7 Advanced SIMD
1636 menu "Userspace binary formats"
1638 source "fs/Kconfig.binfmt"
1641 tristate "RISC OS personality"
1644 Say Y here to include the kernel code necessary if you want to run
1645 Acorn RISC OS/Arthur binaries under Linux. This code is still very
1646 experimental; if this sounds frightening, say N and sleep in peace.
1647 You can also say M here to compile this support as a module (which
1648 will be called arthur).
1652 menu "Power management options"
1654 source "kernel/power/Kconfig"
1656 config ARCH_SUSPEND_POSSIBLE
1661 source "net/Kconfig"
1663 source "drivers/Kconfig"
1667 source "arch/arm/Kconfig.debug"
1669 source "security/Kconfig"
1671 source "crypto/Kconfig"
1673 source "lib/Kconfig"