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 "Cortina Systems Gemini"
304 select ARCH_REQUIRE_GPIOLIB
306 Support for the Cortina Systems Gemini family SoCs
314 This is an evaluation board for the StrongARM processor available
315 from Digital. It has limited hardware on-board, including an
316 Ethernet interface, two PCMCIA sockets, two serial ports and a
327 select ARCH_REQUIRE_GPIOLIB
328 select ARCH_HAS_HOLES_MEMORYMODEL
330 This enables support for the Cirrus EP93xx series of CPUs.
332 config ARCH_FOOTBRIDGE
337 Support for systems based on the DC21285 companion chip
338 ("FootBridge"), such as the Simtec CATS and the Rebel NetWinder.
341 bool "Freescale MXC/iMX-based"
343 select GENERIC_CLOCKEVENTS
344 select ARCH_REQUIRE_GPIOLIB
348 Support for Freescale MXC/iMX-based family of processors
351 bool "Freescale STMP3xxx"
355 select ARCH_REQUIRE_GPIOLIB
357 select GENERIC_CLOCKEVENTS
359 select USB_ARCH_HAS_EHCI
361 Support for systems based on the Freescale 3xxx CPUs.
364 bool "Hilscher NetX based"
367 select GENERIC_CLOCKEVENTS
370 This enables support for systems based on the Hilscher NetX Soc
373 bool "Hynix HMS720x-based"
377 This enables support for systems based on the Hynix HMS720x
385 select ARCH_SUPPORTS_MSI
388 Support for Intel's IOP13XX (XScale) family of processors.
397 select ARCH_REQUIRE_GPIOLIB
399 Support for Intel's 80219 and IOP32X (XScale) family of
409 select ARCH_REQUIRE_GPIOLIB
411 Support for Intel's IOP33X (XScale) family of processors.
419 Support for Intel's IXP23xx (XScale) family of processors.
422 bool "IXP2400/2800-based"
427 Support for Intel's IXP2400/2800 (XScale) family of processors.
435 select GENERIC_CLOCKEVENTS
436 select DMABOUNCE if PCI
438 Support for Intel's IXP4XX (XScale) family of processors.
445 Say Y here if you intend to run this kernel on a LinkUp Systems
446 L7200 Software Development Board which uses an ARM720T processor.
447 Information on this board can be obtained at:
449 <http://www.linkupsys.com/>
451 If you have any questions or comments about the Linux kernel port
452 to this board, send e-mail to <sjhill@cotw.com>.
458 select ARCH_REQUIRE_GPIOLIB
460 select GENERIC_CLOCKEVENTS
463 Support for the Marvell Dove SoC 88AP510
466 bool "Marvell Kirkwood"
470 select ARCH_REQUIRE_GPIOLIB
472 select GENERIC_CLOCKEVENTS
475 Support for the following Marvell Kirkwood series SoCs:
476 88F6180, 88F6192 and 88F6281.
479 bool "Marvell Loki (88RC8480)"
482 select GENERIC_CLOCKEVENTS
485 Support for the Marvell Loki (88RC8480) SoC.
488 bool "Marvell MV78xx0"
492 select ARCH_REQUIRE_GPIOLIB
494 select GENERIC_CLOCKEVENTS
497 Support for the following Marvell MV78xx0 series SoCs:
506 select ARCH_REQUIRE_GPIOLIB
508 select GENERIC_CLOCKEVENTS
511 Support for the following Marvell Orion 5x series SoCs:
512 Orion-1 (5181), Orion-VoIP (5181L), Orion-NAS (5182),
513 Orion-2 (5281), Orion-1-90 (6183).
516 bool "Marvell PXA168/910/MMP2"
519 select ARCH_REQUIRE_GPIOLIB
523 select GENERIC_CLOCKEVENTS
527 Support for Marvell's PXA168/PXA910(MMP) and MMP2 processor line.
530 bool "Micrel/Kendin KS8695"
533 select ARCH_REQUIRE_GPIOLIB
535 Support for Micrel/Kendin KS8695 "Centaur" (ARM922T) based
536 System-on-Chip devices.
539 bool "NetSilicon NS9xxx"
543 select GENERIC_CLOCKEVENTS
546 Say Y here if you intend to run this kernel on a NetSilicon NS9xxx
549 <http://www.digi.com/products/microprocessors/index.jsp>
552 bool "Nuvoton W90X900 CPU"
554 select ARCH_REQUIRE_GPIOLIB
559 select GENERIC_CLOCKEVENTS
561 Support for Nuvoton (Winbond logic dept.) ARM9 processor,
562 At present, the w90x900 has been renamed nuc900, regarding
563 the ARM series product line, you can login the following
564 link address to know more.
566 <http://www.nuvoton.com/hq/enu/ProductAndSales/ProductLines/
567 ConsumerElectronicsIC/ARMMicrocontroller/ARMMicrocontroller>
570 bool "Nuvoton NUC93X CPU"
575 Support for Nuvoton (Winbond logic dept.) NUC93X MCU,The NUC93X is a
576 low-power and high performance MPEG-4/JPEG multimedia controller chip.
579 bool "Philips Nexperia PNX4008 Mobile"
584 This enables support for Philips PNX4008 mobile platform.
587 bool "PXA2xx/PXA3xx-based"
590 select ARCH_HAS_CPUFREQ
594 select ARCH_REQUIRE_GPIOLIB
596 select GENERIC_CLOCKEVENTS
600 Support for Intel/Marvell's PXA2xx/PXA3xx processor line.
606 select GENERIC_CLOCKEVENTS
608 Support for Qualcomm MSM7K based systems. This runs on the ARM11
609 apps processor of the MSM7K and depends on a shared memory
610 interface to the ARM9 modem processor which runs the baseband stack
611 and controls some vital subsystems (clock and power control, etc).
614 bool "Renesas SH-Mobile"
616 Support for Renesas's SH-Mobile ARM platforms
623 select ARCH_MAY_HAVE_PC_FDC
624 select HAVE_PATA_PLATFORM
627 select ARCH_SPARSEMEM_ENABLE
629 On the Acorn Risc-PC, Linux can support the internal IDE disk and
630 CD-ROM interface, serial and parallel port, and the floppy drive.
636 select ARCH_SPARSEMEM_ENABLE
638 select ARCH_HAS_CPUFREQ
642 select GENERIC_CLOCKEVENTS
645 select ARCH_REQUIRE_GPIOLIB
647 Support for StrongARM 11x0 based boards.
650 bool "Samsung S3C2410, S3C2412, S3C2413, S3C2416, S3C2440, S3C2442, S3C2443, S3C2450"
652 select ARCH_HAS_CPUFREQ
655 Samsung S3C2410X CPU based systems, such as the Simtec Electronics
656 BAST (<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or
657 the Samsung SMDK2410 development board (and derivatives).
659 Note, the S3C2416 and the S3C2450 are so close that they even share
660 the same SoC ID code. This means that there is no seperate machine
661 directory (no arch/arm/mach-s3c2450) as the S3C2416 was first.
664 bool "Samsung S3C64XX"
671 select ARCH_HAS_CPUFREQ
672 select ARCH_REQUIRE_GPIOLIB
673 select SAMSUNG_CLKSRC
674 select SAMSUNG_IRQ_VIC_TIMER
675 select SAMSUNG_IRQ_UART
676 select S3C_GPIO_TRACK
677 select S3C_GPIO_PULL_UPDOWN
678 select S3C_GPIO_CFG_S3C24XX
679 select S3C_GPIO_CFG_S3C64XX
681 select USB_ARCH_HAS_OHCI
682 select SAMSUNG_GPIOLIB_4BIT
684 Samsung S3C64XX series based systems
687 bool "Samsung S5P6440"
692 Samsung S5P6440 CPU based systems
695 bool "Samsung S5P6442"
700 Samsung S5P6442 CPU based systems
703 bool "Samsung S5PC100"
707 select ARM_L1_CACHE_SHIFT_6
709 Samsung S5PC100 series based systems
712 bool "Samsung S5PV210/S5PC110"
716 select ARM_L1_CACHE_SHIFT_6
718 Samsung S5PV210/S5PC110 series based systems
728 Support for the StrongARM based Digital DNARD machine, also known
729 as "Shark" (<http://www.shark-linux.de/shark.html>).
734 select ARCH_DISCONTIGMEM_ENABLE if !LH7A40X_CONTIGMEM
735 select ARCH_SPARSEMEM_ENABLE if !LH7A40X_CONTIGMEM
737 Say Y here for systems based on one of the Sharp LH7A40X
738 System on a Chip processors. These CPUs include an ARM922T
739 core with a wide array of integrated devices for
740 hand-held and low-power applications.
743 bool "ST-Ericsson U300 Series"
750 select GENERIC_CLOCKEVENTS
755 Support for ST-Ericsson U300 series mobile platforms.
758 bool "ST-Ericsson U8500 Series"
762 select GENERIC_CLOCKEVENTS
765 Support for ST-Ericsson's Ux500 architecture
768 bool "STMicroelectronics Nomadik"
775 select GENERIC_CLOCKEVENTS
777 select ARCH_REQUIRE_GPIOLIB
779 Support for the Nomadik platform by ST-Ericsson
785 select GENERIC_CLOCKEVENTS
787 select ARCH_REQUIRE_GPIOLIB
792 select GENERIC_ALLOCATOR
793 select ARCH_HAS_HOLES_MEMORYMODEL
795 Support for TI's DaVinci platform.
801 select ARCH_REQUIRE_GPIOLIB
802 select ARCH_HAS_CPUFREQ
804 select GENERIC_CLOCKEVENTS
805 select ARCH_HAS_HOLES_MEMORYMODEL
807 Support for TI's OMAP platform (OMAP1 and OMAP2).
812 # This is sorted alphabetically by mach-* pathname. However, plat-*
813 # Kconfigs may be included either alphabetically (according to the
814 # plat- suffix) or along side the corresponding mach-* source.
816 source "arch/arm/mach-aaec2000/Kconfig"
818 source "arch/arm/mach-at91/Kconfig"
820 source "arch/arm/mach-bcmring/Kconfig"
822 source "arch/arm/mach-clps711x/Kconfig"
824 source "arch/arm/mach-davinci/Kconfig"
826 source "arch/arm/mach-dove/Kconfig"
828 source "arch/arm/mach-ep93xx/Kconfig"
830 source "arch/arm/mach-footbridge/Kconfig"
832 source "arch/arm/mach-gemini/Kconfig"
834 source "arch/arm/mach-h720x/Kconfig"
836 source "arch/arm/mach-integrator/Kconfig"
838 source "arch/arm/mach-iop32x/Kconfig"
840 source "arch/arm/mach-iop33x/Kconfig"
842 source "arch/arm/mach-iop13xx/Kconfig"
844 source "arch/arm/mach-ixp4xx/Kconfig"
846 source "arch/arm/mach-ixp2000/Kconfig"
848 source "arch/arm/mach-ixp23xx/Kconfig"
850 source "arch/arm/mach-kirkwood/Kconfig"
852 source "arch/arm/mach-ks8695/Kconfig"
854 source "arch/arm/mach-lh7a40x/Kconfig"
856 source "arch/arm/mach-loki/Kconfig"
858 source "arch/arm/mach-msm/Kconfig"
860 source "arch/arm/mach-mv78xx0/Kconfig"
862 source "arch/arm/plat-mxc/Kconfig"
864 source "arch/arm/mach-netx/Kconfig"
866 source "arch/arm/mach-nomadik/Kconfig"
867 source "arch/arm/plat-nomadik/Kconfig"
869 source "arch/arm/mach-ns9xxx/Kconfig"
871 source "arch/arm/mach-nuc93x/Kconfig"
873 source "arch/arm/plat-omap/Kconfig"
875 source "arch/arm/mach-omap1/Kconfig"
877 source "arch/arm/mach-omap2/Kconfig"
879 source "arch/arm/mach-orion5x/Kconfig"
881 source "arch/arm/mach-pxa/Kconfig"
882 source "arch/arm/plat-pxa/Kconfig"
884 source "arch/arm/mach-mmp/Kconfig"
886 source "arch/arm/mach-realview/Kconfig"
888 source "arch/arm/mach-sa1100/Kconfig"
890 source "arch/arm/plat-samsung/Kconfig"
891 source "arch/arm/plat-s3c24xx/Kconfig"
892 source "arch/arm/plat-s5p/Kconfig"
895 source "arch/arm/mach-s3c2400/Kconfig"
896 source "arch/arm/mach-s3c2410/Kconfig"
897 source "arch/arm/mach-s3c2412/Kconfig"
898 source "arch/arm/mach-s3c2416/Kconfig"
899 source "arch/arm/mach-s3c2440/Kconfig"
900 source "arch/arm/mach-s3c2443/Kconfig"
904 source "arch/arm/mach-s3c64xx/Kconfig"
907 source "arch/arm/mach-s5p6440/Kconfig"
909 source "arch/arm/mach-s5p6442/Kconfig"
911 source "arch/arm/mach-s5pc100/Kconfig"
913 source "arch/arm/mach-s5pv210/Kconfig"
915 source "arch/arm/mach-shmobile/Kconfig"
917 source "arch/arm/plat-stmp3xxx/Kconfig"
919 source "arch/arm/mach-u300/Kconfig"
921 source "arch/arm/mach-ux500/Kconfig"
923 source "arch/arm/mach-versatile/Kconfig"
925 source "arch/arm/mach-w90x900/Kconfig"
927 # Definitions to make life easier
933 select GENERIC_CLOCKEVENTS
942 source arch/arm/mm/Kconfig
945 bool "Enable iWMMXt support"
946 depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK
947 default y if PXA27x || PXA3xx || ARCH_MMP
949 Enable support for iWMMXt context switching at run time if
950 running on a CPU that supports it.
952 # bool 'Use XScale PMU as timer source' CONFIG_XSCALE_PMU_TIMER
955 depends on CPU_XSCALE && !XSCALE_PMU_TIMER
959 depends on CPU_V6 || CPU_V7 || XSCALE_PMU
964 source "arch/arm/Kconfig-nommu"
967 config ARM_ERRATA_411920
968 bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
969 depends on CPU_V6 && !SMP
971 Invalidation of the Instruction Cache operation can
972 fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
973 It does not affect the MPCore. This option enables the ARM Ltd.
974 recommended workaround.
976 config ARM_ERRATA_430973
977 bool "ARM errata: Stale prediction on replaced interworking branch"
980 This option enables the workaround for the 430973 Cortex-A8
981 (r1p0..r1p2) erratum. If a code sequence containing an ARM/Thumb
982 interworking branch is replaced with another code sequence at the
983 same virtual address, whether due to self-modifying code or virtual
984 to physical address re-mapping, Cortex-A8 does not recover from the
985 stale interworking branch prediction. This results in Cortex-A8
986 executing the new code sequence in the incorrect ARM or Thumb state.
987 The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
988 and also flushes the branch target cache at every context switch.
989 Note that setting specific bits in the ACTLR register may not be
990 available in non-secure mode.
992 config ARM_ERRATA_458693
993 bool "ARM errata: Processor deadlock when a false hazard is created"
996 This option enables the workaround for the 458693 Cortex-A8 (r2p0)
997 erratum. For very specific sequences of memory operations, it is
998 possible for a hazard condition intended for a cache line to instead
999 be incorrectly associated with a different cache line. This false
1000 hazard might then cause a processor deadlock. The workaround enables
1001 the L1 caching of the NEON accesses and disables the PLD instruction
1002 in the ACTLR register. Note that setting specific bits in the ACTLR
1003 register may not be available in non-secure mode.
1005 config ARM_ERRATA_460075
1006 bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
1009 This option enables the workaround for the 460075 Cortex-A8 (r2p0)
1010 erratum. Any asynchronous access to the L2 cache may encounter a
1011 situation in which recent store transactions to the L2 cache are lost
1012 and overwritten with stale memory contents from external memory. The
1013 workaround disables the write-allocate mode for the L2 cache via the
1014 ACTLR register. Note that setting specific bits in the ACTLR register
1015 may not be available in non-secure mode.
1017 config PL310_ERRATA_588369
1018 bool "Clean & Invalidate maintenance operations do not invalidate clean lines"
1019 depends on CACHE_L2X0 && ARCH_OMAP4
1021 The PL310 L2 cache controller implements three types of Clean &
1022 Invalidate maintenance operations: by Physical Address
1023 (offset 0x7F0), by Index/Way (0x7F8) and by Way (0x7FC).
1024 They are architecturally defined to behave as the execution of a
1025 clean operation followed immediately by an invalidate operation,
1026 both performing to the same memory location. This functionality
1027 is not correctly implemented in PL310 as clean lines are not
1028 invalidated as a result of these operations. Note that this errata
1029 uses Texas Instrument's secure monitor api.
1032 source "arch/arm/common/Kconfig"
1034 config FORCE_MAX_ZONEORDER
1047 Find out whether you have ISA slots on your motherboard. ISA is the
1048 name of a bus system, i.e. the way the CPU talks to the other stuff
1049 inside your box. Other bus systems are PCI, EISA, MicroChannel
1050 (MCA) or VESA. ISA is an older system, now being displaced by PCI;
1051 newer boards don't support it. If you have ISA, say Y, otherwise N.
1053 # Select ISA DMA controller support
1058 # Select ISA DMA interface
1063 bool "PCI support" if ARCH_INTEGRATOR_AP || ARCH_VERSATILE_PB || ARCH_IXP4XX || ARCH_KS8695 || MACH_ARMCORE
1065 Find out whether you have a PCI motherboard. PCI is the name of a
1066 bus system, i.e. the way the CPU talks to the other stuff inside
1067 your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
1068 VESA. If you have PCI, say Y, otherwise N.
1073 # Select the host bridge type
1074 config PCI_HOST_VIA82C505
1076 depends on PCI && ARCH_SHARK
1079 config PCI_HOST_ITE8152
1081 depends on PCI && MACH_ARMCORE
1085 source "drivers/pci/Kconfig"
1087 source "drivers/pcmcia/Kconfig"
1091 menu "Kernel Features"
1093 source "kernel/time/Kconfig"
1096 bool "Symmetric Multi-Processing (EXPERIMENTAL)"
1097 depends on EXPERIMENTAL && (REALVIEW_EB_ARM11MP || REALVIEW_EB_A9MP ||\
1098 MACH_REALVIEW_PB11MP || MACH_REALVIEW_PBX || ARCH_OMAP4 || ARCH_U8500)
1099 depends on GENERIC_CLOCKEVENTS
1100 select USE_GENERIC_SMP_HELPERS
1101 select HAVE_ARM_SCU if (ARCH_REALVIEW || ARCH_OMAP4 || ARCH_U8500)
1103 This enables support for systems with more than one CPU. If you have
1104 a system with only one CPU, like most personal computers, say N. If
1105 you have a system with more than one CPU, say Y.
1107 If you say N here, the kernel will run on single and multiprocessor
1108 machines, but will use only one CPU of a multiprocessor machine. If
1109 you say Y here, the kernel will run on many, but not all, single
1110 processor machines. On a single processor machine, the kernel will
1111 run faster if you say N here.
1113 See also <file:Documentation/i386/IO-APIC.txt>,
1114 <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
1115 <http://www.linuxdoc.org/docs.html#howto>.
1117 If you don't know what to do here, say N.
1123 This option enables support for the ARM system coherency unit
1129 This options enables support for the ARM timer and watchdog unit
1132 prompt "Memory split"
1135 Select the desired split between kernel and user memory.
1137 If you are not absolutely sure what you are doing, leave this
1141 bool "3G/1G user/kernel split"
1143 bool "2G/2G user/kernel split"
1145 bool "1G/3G user/kernel split"
1150 default 0x40000000 if VMSPLIT_1G
1151 default 0x80000000 if VMSPLIT_2G
1155 int "Maximum number of CPUs (2-32)"
1161 bool "Support for hot-pluggable CPUs (EXPERIMENTAL)"
1162 depends on SMP && HOTPLUG && EXPERIMENTAL
1164 Say Y here to experiment with turning CPUs off and on. CPUs
1165 can be controlled through /sys/devices/system/cpu.
1168 bool "Use local timer interrupts"
1169 depends on SMP && (REALVIEW_EB_ARM11MP || MACH_REALVIEW_PB11MP || \
1170 REALVIEW_EB_A9MP || MACH_REALVIEW_PBX || ARCH_OMAP4 || ARCH_U8500)
1172 select HAVE_ARM_TWD if (ARCH_REALVIEW || ARCH_OMAP4 || ARCH_U8500)
1174 Enable support for local timers on SMP platforms, rather then the
1175 legacy IPI broadcast method. Local timers allows the system
1176 accounting to be spread across the timer interval, preventing a
1177 "thundering herd" at every timer tick.
1179 source kernel/Kconfig.preempt
1183 default 128 if ARCH_L7200
1184 default 200 if ARCH_EBSA110 || ARCH_S3C2410 || ARCH_S5P6440 || ARCH_S5P6442 || ARCH_S5PV210
1185 default OMAP_32K_TIMER_HZ if ARCH_OMAP && OMAP_32K_TIMER
1186 default AT91_TIMER_HZ if ARCH_AT91
1189 config THUMB2_KERNEL
1190 bool "Compile the kernel in Thumb-2 mode"
1191 depends on CPU_V7 && EXPERIMENTAL
1193 select ARM_ASM_UNIFIED
1195 By enabling this option, the kernel will be compiled in
1196 Thumb-2 mode. A compiler/assembler that understand the unified
1197 ARM-Thumb syntax is needed.
1201 config ARM_ASM_UNIFIED
1205 bool "Use the ARM EABI to compile the kernel"
1207 This option allows for the kernel to be compiled using the latest
1208 ARM ABI (aka EABI). This is only useful if you are using a user
1209 space environment that is also compiled with EABI.
1211 Since there are major incompatibilities between the legacy ABI and
1212 EABI, especially with regard to structure member alignment, this
1213 option also changes the kernel syscall calling convention to
1214 disambiguate both ABIs and allow for backward compatibility support
1215 (selected with CONFIG_OABI_COMPAT).
1217 To use this you need GCC version 4.0.0 or later.
1220 bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
1221 depends on AEABI && EXPERIMENTAL
1224 This option preserves the old syscall interface along with the
1225 new (ARM EABI) one. It also provides a compatibility layer to
1226 intercept syscalls that have structure arguments which layout
1227 in memory differs between the legacy ABI and the new ARM EABI
1228 (only for non "thumb" binaries). This option adds a tiny
1229 overhead to all syscalls and produces a slightly larger kernel.
1230 If you know you'll be using only pure EABI user space then you
1231 can say N here. If this option is not selected and you attempt
1232 to execute a legacy ABI binary then the result will be
1233 UNPREDICTABLE (in fact it can be predicted that it won't work
1234 at all). If in doubt say Y.
1236 config ARCH_HAS_HOLES_MEMORYMODEL
1239 # Discontigmem is deprecated
1240 config ARCH_DISCONTIGMEM_ENABLE
1243 config ARCH_SPARSEMEM_ENABLE
1246 config ARCH_SPARSEMEM_DEFAULT
1247 def_bool ARCH_SPARSEMEM_ENABLE
1249 config ARCH_SELECT_MEMORY_MODEL
1250 def_bool ARCH_DISCONTIGMEM_ENABLE && ARCH_SPARSEMEM_ENABLE
1254 default "4" if ARCH_LH7A40X
1256 depends on NEED_MULTIPLE_NODES
1259 bool "High Memory Support (EXPERIMENTAL)"
1260 depends on MMU && EXPERIMENTAL
1262 The address space of ARM processors is only 4 Gigabytes large
1263 and it has to accommodate user address space, kernel address
1264 space as well as some memory mapped IO. That means that, if you
1265 have a large amount of physical memory and/or IO, not all of the
1266 memory can be "permanently mapped" by the kernel. The physical
1267 memory that is not permanently mapped is called "high memory".
1269 Depending on the selected kernel/user memory split, minimum
1270 vmalloc space and actual amount of RAM, you may not need this
1271 option which should result in a slightly faster kernel.
1276 bool "Allocate 2nd-level pagetables from highmem"
1278 depends on !OUTER_CACHE
1280 config HW_PERF_EVENTS
1281 bool "Enable hardware performance counter support for perf events"
1282 depends on PERF_EVENTS && CPU_HAS_PMU && (CPU_V6 || CPU_V7)
1285 Enable hardware performance counter support for perf events. If
1286 disabled, perf events will use software events only.
1291 bool "Timer and CPU usage LEDs"
1292 depends on ARCH_CDB89712 || ARCH_EBSA110 || \
1293 ARCH_EBSA285 || ARCH_INTEGRATOR || \
1294 ARCH_LUBBOCK || MACH_MAINSTONE || ARCH_NETWINDER || \
1295 ARCH_OMAP || ARCH_P720T || ARCH_PXA_IDP || \
1296 ARCH_SA1100 || ARCH_SHARK || ARCH_VERSATILE || \
1297 ARCH_AT91 || ARCH_DAVINCI || \
1298 ARCH_KS8695 || MACH_RD88F5182 || ARCH_REALVIEW
1300 If you say Y here, the LEDs on your machine will be used
1301 to provide useful information about your current system status.
1303 If you are compiling a kernel for a NetWinder or EBSA-285, you will
1304 be able to select which LEDs are active using the options below. If
1305 you are compiling a kernel for the EBSA-110 or the LART however, the
1306 red LED will simply flash regularly to indicate that the system is
1307 still functional. It is safe to say Y here if you have a CATS
1308 system, but the driver will do nothing.
1311 bool "Timer LED" if (!ARCH_CDB89712 && !ARCH_OMAP) || \
1312 OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1313 || MACH_OMAP_PERSEUS2
1315 depends on !GENERIC_CLOCKEVENTS
1316 default y if ARCH_EBSA110
1318 If you say Y here, one of the system LEDs (the green one on the
1319 NetWinder, the amber one on the EBSA285, or the red one on the LART)
1320 will flash regularly to indicate that the system is still
1321 operational. This is mainly useful to kernel hackers who are
1322 debugging unstable kernels.
1324 The LART uses the same LED for both Timer LED and CPU usage LED
1325 functions. You may choose to use both, but the Timer LED function
1326 will overrule the CPU usage LED.
1329 bool "CPU usage LED" if (!ARCH_CDB89712 && !ARCH_EBSA110 && \
1331 || OMAP_OSK_MISTRAL || MACH_OMAP_H2 \
1332 || MACH_OMAP_PERSEUS2
1335 If you say Y here, the red LED will be used to give a good real
1336 time indication of CPU usage, by lighting whenever the idle task
1337 is not currently executing.
1339 The LART uses the same LED for both Timer LED and CPU usage LED
1340 functions. You may choose to use both, but the Timer LED function
1341 will overrule the CPU usage LED.
1343 config ALIGNMENT_TRAP
1345 depends on CPU_CP15_MMU
1346 default y if !ARCH_EBSA110
1347 select HAVE_PROC_CPU if PROC_FS
1349 ARM processors cannot fetch/store information which is not
1350 naturally aligned on the bus, i.e., a 4 byte fetch must start at an
1351 address divisible by 4. On 32-bit ARM processors, these non-aligned
1352 fetch/store instructions will be emulated in software if you say
1353 here, which has a severe performance impact. This is necessary for
1354 correct operation of some network protocols. With an IP-only
1355 configuration it is safe to say N, otherwise say Y.
1357 config UACCESS_WITH_MEMCPY
1358 bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user() (EXPERIMENTAL)"
1359 depends on MMU && EXPERIMENTAL
1360 default y if CPU_FEROCEON
1362 Implement faster copy_to_user and clear_user methods for CPU
1363 cores where a 8-word STM instruction give significantly higher
1364 memory write throughput than a sequence of individual 32bit stores.
1366 A possible side effect is a slight increase in scheduling latency
1367 between threads sharing the same address space if they invoke
1368 such copy operations with large buffers.
1370 However, if the CPU data cache is using a write-allocate mode,
1371 this option is unlikely to provide any performance gain.
1377 # Compressed boot loader in ROM. Yes, we really want to ask about
1378 # TEXT and BSS so we preserve their values in the config files.
1379 config ZBOOT_ROM_TEXT
1380 hex "Compressed ROM boot loader base address"
1383 The physical address at which the ROM-able zImage is to be
1384 placed in the target. Platforms which normally make use of
1385 ROM-able zImage formats normally set this to a suitable
1386 value in their defconfig file.
1388 If ZBOOT_ROM is not enabled, this has no effect.
1390 config ZBOOT_ROM_BSS
1391 hex "Compressed ROM boot loader BSS address"
1394 The base address of an area of read/write memory in the target
1395 for the ROM-able zImage which must be available while the
1396 decompressor is running. It must be large enough to hold the
1397 entire decompressed kernel plus an additional 128 KiB.
1398 Platforms which normally make use of ROM-able zImage formats
1399 normally set this to a suitable value in their defconfig file.
1401 If ZBOOT_ROM is not enabled, this has no effect.
1404 bool "Compressed boot loader in ROM/flash"
1405 depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
1407 Say Y here if you intend to execute your compressed kernel image
1408 (zImage) directly from ROM or flash. If unsure, say N.
1411 string "Default kernel command string"
1414 On some architectures (EBSA110 and CATS), there is currently no way
1415 for the boot loader to pass arguments to the kernel. For these
1416 architectures, you should supply some command-line options at build
1417 time by entering them here. As a minimum, you should specify the
1418 memory size and the root device (e.g., mem=64M root=/dev/nfs).
1421 bool "Kernel Execute-In-Place from ROM"
1422 depends on !ZBOOT_ROM
1424 Execute-In-Place allows the kernel to run from non-volatile storage
1425 directly addressable by the CPU, such as NOR flash. This saves RAM
1426 space since the text section of the kernel is not loaded from flash
1427 to RAM. Read-write sections, such as the data section and stack,
1428 are still copied to RAM. The XIP kernel is not compressed since
1429 it has to run directly from flash, so it will take more space to
1430 store it. The flash address used to link the kernel object files,
1431 and for storing it, is configuration dependent. Therefore, if you
1432 say Y here, you must know the proper physical address where to
1433 store the kernel image depending on your own flash memory usage.
1435 Also note that the make target becomes "make xipImage" rather than
1436 "make zImage" or "make Image". The final kernel binary to put in
1437 ROM memory will be arch/arm/boot/xipImage.
1441 config XIP_PHYS_ADDR
1442 hex "XIP Kernel Physical Location"
1443 depends on XIP_KERNEL
1444 default "0x00080000"
1446 This is the physical address in your flash memory the kernel will
1447 be linked for and stored to. This address is dependent on your
1451 bool "Kexec system call (EXPERIMENTAL)"
1452 depends on EXPERIMENTAL
1454 kexec is a system call that implements the ability to shutdown your
1455 current kernel, and to start another kernel. It is like a reboot
1456 but it is independent of the system firmware. And like a reboot
1457 you can start any kernel with it, not just Linux.
1459 It is an ongoing process to be certain the hardware in a machine
1460 is properly shutdown, so do not be surprised if this code does not
1461 initially work for you. It may help to enable device hotplugging
1465 bool "Export atags in procfs"
1469 Should the atags used to boot the kernel be exported in an "atags"
1470 file in procfs. Useful with kexec.
1474 menu "CPU Power Management"
1478 source "drivers/cpufreq/Kconfig"
1480 config CPU_FREQ_SA1100
1483 config CPU_FREQ_SA1110
1486 config CPU_FREQ_INTEGRATOR
1487 tristate "CPUfreq driver for ARM Integrator CPUs"
1488 depends on ARCH_INTEGRATOR && CPU_FREQ
1491 This enables the CPUfreq driver for ARM Integrator CPUs.
1493 For details, take a look at <file:Documentation/cpu-freq>.
1499 depends on CPU_FREQ && ARCH_PXA && PXA25x
1501 select CPU_FREQ_DEFAULT_GOV_USERSPACE
1503 config CPU_FREQ_S3C64XX
1504 bool "CPUfreq support for Samsung S3C64XX CPUs"
1505 depends on CPU_FREQ && CPU_S3C6410
1510 Internal configuration node for common cpufreq on Samsung SoC
1512 config CPU_FREQ_S3C24XX
1513 bool "CPUfreq driver for Samsung S3C24XX series CPUs"
1514 depends on ARCH_S3C2410 && CPU_FREQ && EXPERIMENTAL
1517 This enables the CPUfreq driver for the Samsung S3C24XX family
1520 For details, take a look at <file:Documentation/cpu-freq>.
1524 config CPU_FREQ_S3C24XX_PLL
1525 bool "Support CPUfreq changing of PLL frequency"
1526 depends on CPU_FREQ_S3C24XX && EXPERIMENTAL
1528 Compile in support for changing the PLL frequency from the
1529 S3C24XX series CPUfreq driver. The PLL takes time to settle
1530 after a frequency change, so by default it is not enabled.
1532 This also means that the PLL tables for the selected CPU(s) will
1533 be built which may increase the size of the kernel image.
1535 config CPU_FREQ_S3C24XX_DEBUG
1536 bool "Debug CPUfreq Samsung driver core"
1537 depends on CPU_FREQ_S3C24XX
1539 Enable s3c_freq_dbg for the Samsung S3C CPUfreq core
1541 config CPU_FREQ_S3C24XX_IODEBUG
1542 bool "Debug CPUfreq Samsung driver IO timing"
1543 depends on CPU_FREQ_S3C24XX
1545 Enable s3c_freq_iodbg for the Samsung S3C CPUfreq core
1547 config CPU_FREQ_S3C24XX_DEBUGFS
1548 bool "Export debugfs for CPUFreq"
1549 depends on CPU_FREQ_S3C24XX && DEBUG_FS
1551 Export status information via debugfs.
1555 source "drivers/cpuidle/Kconfig"
1559 menu "Floating point emulation"
1561 comment "At least one emulation must be selected"
1564 bool "NWFPE math emulation"
1565 depends on !AEABI || OABI_COMPAT
1567 Say Y to include the NWFPE floating point emulator in the kernel.
1568 This is necessary to run most binaries. Linux does not currently
1569 support floating point hardware so you need to say Y here even if
1570 your machine has an FPA or floating point co-processor podule.
1572 You may say N here if you are going to load the Acorn FPEmulator
1573 early in the bootup.
1576 bool "Support extended precision"
1577 depends on FPE_NWFPE
1579 Say Y to include 80-bit support in the kernel floating-point
1580 emulator. Otherwise, only 32 and 64-bit support is compiled in.
1581 Note that gcc does not generate 80-bit operations by default,
1582 so in most cases this option only enlarges the size of the
1583 floating point emulator without any good reason.
1585 You almost surely want to say N here.
1588 bool "FastFPE math emulation (EXPERIMENTAL)"
1589 depends on (!AEABI || OABI_COMPAT) && !CPU_32v3 && EXPERIMENTAL
1591 Say Y here to include the FAST floating point emulator in the kernel.
1592 This is an experimental much faster emulator which now also has full
1593 precision for the mantissa. It does not support any exceptions.
1594 It is very simple, and approximately 3-6 times faster than NWFPE.
1596 It should be sufficient for most programs. It may be not suitable
1597 for scientific calculations, but you have to check this for yourself.
1598 If you do not feel you need a faster FP emulation you should better
1602 bool "VFP-format floating point maths"
1603 depends on CPU_V6 || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
1605 Say Y to include VFP support code in the kernel. This is needed
1606 if your hardware includes a VFP unit.
1608 Please see <file:Documentation/arm/VFP/release-notes.txt> for
1609 release notes and additional status information.
1611 Say N if your target does not have VFP hardware.
1619 bool "Advanced SIMD (NEON) Extension support"
1620 depends on VFPv3 && CPU_V7
1622 Say Y to include support code for NEON, the ARMv7 Advanced SIMD
1627 menu "Userspace binary formats"
1629 source "fs/Kconfig.binfmt"
1632 tristate "RISC OS personality"
1635 Say Y here to include the kernel code necessary if you want to run
1636 Acorn RISC OS/Arthur binaries under Linux. This code is still very
1637 experimental; if this sounds frightening, say N and sleep in peace.
1638 You can also say M here to compile this support as a module (which
1639 will be called arthur).
1643 menu "Power management options"
1645 source "kernel/power/Kconfig"
1647 config ARCH_SUSPEND_POSSIBLE
1652 source "net/Kconfig"
1654 source "drivers/Kconfig"
1658 source "arch/arm/Kconfig.debug"
1660 source "security/Kconfig"
1662 source "crypto/Kconfig"
1664 source "lib/Kconfig"