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|
config ARM
bool
default y
select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
select ARCH_HAS_ELF_RANDOMIZE
select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
select ARCH_HAVE_CUSTOM_GPIO_H
select ARCH_HAS_GCOV_PROFILE_ALL
select ARCH_MIGHT_HAVE_PC_PARPORT
select ARCH_SUPPORTS_ATOMIC_RMW
select ARCH_USE_BUILTIN_BSWAP
select ARCH_USE_CMPXCHG_LOCKREF
select ARCH_WANT_IPC_PARSE_VERSION
select BUILDTIME_EXTABLE_SORT if MMU
select CLONE_BACKWARDS
select CPU_PM if (SUSPEND || CPU_IDLE)
select DCACHE_WORD_ACCESS if HAVE_EFFICIENT_UNALIGNED_ACCESS
select EDAC_SUPPORT
select EDAC_ATOMIC_SCRUB
select GENERIC_ALLOCATOR
select GENERIC_ATOMIC64 if (CPU_V7M || CPU_V6 || !CPU_32v6K || !AEABI)
select GENERIC_CLOCKEVENTS_BROADCAST if SMP
select GENERIC_IDLE_POLL_SETUP
select GENERIC_IRQ_PROBE
select GENERIC_IRQ_SHOW
select GENERIC_IRQ_SHOW_LEVEL
select GENERIC_PCI_IOMAP
select GENERIC_SCHED_CLOCK
select GENERIC_SMP_IDLE_THREAD
select GENERIC_STRNCPY_FROM_USER
select GENERIC_STRNLEN_USER
select HANDLE_DOMAIN_IRQ
select HARDIRQS_SW_RESEND
select HAVE_ARCH_AUDITSYSCALL if (AEABI && !OABI_COMPAT)
select HAVE_ARCH_BITREVERSE if (CPU_32v7M || CPU_32v7) && !CPU_32v6
select HAVE_ARCH_JUMP_LABEL if !XIP_KERNEL && !CPU_ENDIAN_BE32
select HAVE_ARCH_KGDB if !CPU_ENDIAN_BE32
select HAVE_ARCH_MMAP_RND_BITS if MMU
select HAVE_ARCH_HARDENED_USERCOPY
select HAVE_ARCH_SECCOMP_FILTER if (AEABI && !OABI_COMPAT)
select HAVE_ARCH_TRACEHOOK
select HAVE_ARM_SMCCC if CPU_V7
select HAVE_BPF_JIT
select HAVE_CC_STACKPROTECTOR
select HAVE_CONTEXT_TRACKING
select HAVE_C_RECORDMCOUNT
select HAVE_DEBUG_KMEMLEAK
select HAVE_DMA_API_DEBUG
select HAVE_DMA_ATTRS
select HAVE_DMA_CONTIGUOUS if MMU
select HAVE_DYNAMIC_FTRACE if (!XIP_KERNEL) && !CPU_ENDIAN_BE32
select HAVE_EFFICIENT_UNALIGNED_ACCESS if (CPU_V6 || CPU_V6K || CPU_V7) && MMU
select HAVE_EXIT_THREAD
select HAVE_FTRACE_MCOUNT_RECORD if (!XIP_KERNEL)
select HAVE_FUNCTION_GRAPH_TRACER if (!THUMB2_KERNEL)
select HAVE_FUNCTION_TRACER if (!XIP_KERNEL)
select HAVE_FUTEX_CMPXCHG if FUTEX
select HAVE_GENERIC_DMA_COHERENT
select HAVE_HW_BREAKPOINT if (PERF_EVENTS && (CPU_V6 || CPU_V6K || CPU_V7))
select HAVE_IDE if PCI || ISA || PCMCIA
select HAVE_IRQ_TIME_ACCOUNTING
select HAVE_KERNEL_GZIP
select HAVE_KERNEL_LZ4
select HAVE_KERNEL_LZMA
select HAVE_KERNEL_LZO
select HAVE_KERNEL_XZ
select HAVE_KPROBES if !XIP_KERNEL && !CPU_ENDIAN_BE32 && !CPU_V7M
select HAVE_KRETPROBES if (HAVE_KPROBES)
select HAVE_MEMBLOCK
select HAVE_MOD_ARCH_SPECIFIC
select HAVE_OPROFILE if (HAVE_PERF_EVENTS)
select HAVE_OPTPROBES if !THUMB2_KERNEL
select HAVE_PERF_EVENTS
select HAVE_PERF_REGS
select HAVE_PERF_USER_STACK_DUMP
select HAVE_RCU_TABLE_FREE if (SMP && ARM_LPAE)
select HAVE_REGS_AND_STACK_ACCESS_API
select HAVE_SYSCALL_TRACEPOINTS
select HAVE_UID16
select HAVE_VIRT_CPU_ACCOUNTING_GEN
select IRQ_FORCED_THREADING
select MODULES_USE_ELF_REL
select NO_BOOTMEM
select OF_EARLY_FLATTREE if OF
select OF_RESERVED_MEM if OF
select OLD_SIGACTION
select OLD_SIGSUSPEND3
select PERF_USE_VMALLOC
select RTC_LIB
select SYS_SUPPORTS_APM_EMULATION
# Above selects are sorted alphabetically; please add new ones
# according to that. Thanks.
help
The ARM series is a line of low-power-consumption RISC chip designs
licensed by ARM Ltd and targeted at embedded applications and
handhelds such as the Compaq IPAQ. ARM-based PCs are no longer
manufactured, but legacy ARM-based PC hardware remains popular in
Europe. There is an ARM Linux project with a web page at
<http://www.arm.linux.org.uk/>.
config ARM_HAS_SG_CHAIN
select ARCH_HAS_SG_CHAIN
bool
config NEED_SG_DMA_LENGTH
bool
config ARM_DMA_USE_IOMMU
bool
select ARM_HAS_SG_CHAIN
select NEED_SG_DMA_LENGTH
if ARM_DMA_USE_IOMMU
config ARM_DMA_IOMMU_ALIGNMENT
int "Maximum PAGE_SIZE order of alignment for DMA IOMMU buffers"
range 4 9
default 9
help
DMA mapping framework by default aligns all buffers to the smallest
PAGE_SIZE order which is greater than or equal to the requested buffer
size. This works well for buffers up to a few hundreds kilobytes, but
for larger buffers it just a waste of address space. Drivers which has
relatively small addressing window (like 64Mib) might run out of
virtual space with just a few allocations.
With this parameter you can specify the maximum PAGE_SIZE order for
DMA IOMMU buffers. Larger buffers will be aligned only to this
specified order. The order is expressed as a power of two multiplied
by the PAGE_SIZE.
endif
config MIGHT_HAVE_PCI
bool
config SYS_SUPPORTS_APM_EMULATION
bool
config HAVE_TCM
bool
select GENERIC_ALLOCATOR
config HAVE_PROC_CPU
bool
config NO_IOPORT_MAP
bool
config EISA
bool
---help---
The Extended Industry Standard Architecture (EISA) bus was
developed as an open alternative to the IBM MicroChannel bus.
The EISA bus provided some of the features of the IBM MicroChannel
bus while maintaining backward compatibility with cards made for
the older ISA bus. The EISA bus saw limited use between 1988 and
1995 when it was made obsolete by the PCI bus.
Say Y here if you are building a kernel for an EISA-based machine.
Otherwise, say N.
config SBUS
bool
config STACKTRACE_SUPPORT
bool
default y
config HAVE_LATENCYTOP_SUPPORT
bool
depends on !SMP
default y
config LOCKDEP_SUPPORT
bool
default y
config TRACE_IRQFLAGS_SUPPORT
bool
default !CPU_V7M
config RWSEM_XCHGADD_ALGORITHM
bool
default y
config ARCH_HAS_ILOG2_U32
bool
config ARCH_HAS_ILOG2_U64
bool
config ARCH_HAS_BANDGAP
bool
config FIX_EARLYCON_MEM
def_bool y if MMU
config GENERIC_HWEIGHT
bool
default y
config GENERIC_CALIBRATE_DELAY
bool
default y
config ARCH_MAY_HAVE_PC_FDC
bool
config ZONE_DMA
bool
config NEED_DMA_MAP_STATE
def_bool y
config ARCH_SUPPORTS_UPROBES
def_bool y
config ARCH_HAS_DMA_SET_COHERENT_MASK
bool
config GENERIC_ISA_DMA
bool
config FIQ
bool
config NEED_RET_TO_USER
bool
config ARCH_MTD_XIP
bool
config ARCH_WANT_KMAP_ATOMIC_FLUSH
bool
config VECTORS_BASE
hex
default 0xffff0000 if MMU || CPU_HIGH_VECTOR
default DRAM_BASE if REMAP_VECTORS_TO_RAM
default 0x00000000
help
The base address of exception vectors. This must be two pages
in size.
config ARM_PATCH_PHYS_VIRT
bool "Patch physical to virtual translations at runtime" if EMBEDDED
default y
depends on !XIP_KERNEL && MMU
depends on !ARCH_REALVIEW || !SPARSEMEM
help
Patch phys-to-virt and virt-to-phys translation functions at
boot and module load time according to the position of the
kernel in system memory.
This can only be used with non-XIP MMU kernels where the base
of physical memory is at a 16MB boundary.
Only disable this option if you know that you do not require
this feature (eg, building a kernel for a single machine) and
you need to shrink the kernel to the minimal size.
config NEED_MACH_IO_H
bool
help
Select this when mach/io.h is required to provide special
definitions for this platform. The need for mach/io.h should
be avoided when possible.
config NEED_MACH_MEMORY_H
bool
help
Select this when mach/memory.h is required to provide special
definitions for this platform. The need for mach/memory.h should
be avoided when possible.
config PHYS_OFFSET
hex "Physical address of main memory" if MMU
depends on !ARM_PATCH_PHYS_VIRT
default DRAM_BASE if !MMU
default 0x00000000 if ARCH_EBSA110 || \
ARCH_FOOTBRIDGE || \
ARCH_INTEGRATOR || \
ARCH_IOP13XX || \
ARCH_KS8695 || \
(ARCH_REALVIEW && !REALVIEW_HIGH_PHYS_OFFSET)
default 0x10000000 if ARCH_OMAP1 || ARCH_RPC
default 0x20000000 if ARCH_S5PV210
default 0x70000000 if REALVIEW_HIGH_PHYS_OFFSET
default 0xc0000000 if ARCH_SA1100
help
Please provide the physical address corresponding to the
location of main memory in your system.
config GENERIC_BUG
def_bool y
depends on BUG
config PGTABLE_LEVELS
int
default 3 if ARM_LPAE
default 2
source "init/Kconfig"
source "kernel/Kconfig.freezer"
menu "System Type"
config MMU
bool "MMU-based Paged Memory Management Support"
default y
help
Select if you want MMU-based virtualised addressing space
support by paged memory management. If unsure, say 'Y'.
config ARCH_MMAP_RND_BITS_MIN
default 8
config ARCH_MMAP_RND_BITS_MAX
default 14 if PAGE_OFFSET=0x40000000
default 15 if PAGE_OFFSET=0x80000000
default 16
#
# The "ARM system type" choice list is ordered alphabetically by option
# text. Please add new entries in the option alphabetic order.
#
choice
prompt "ARM system type"
default ARCH_VERSATILE if !MMU
default ARCH_MULTIPLATFORM if MMU
config ARCH_MULTIPLATFORM
bool "Allow multiple platforms to be selected"
depends on MMU
select ARCH_WANT_OPTIONAL_GPIOLIB
select ARM_HAS_SG_CHAIN
select ARM_PATCH_PHYS_VIRT
select AUTO_ZRELADDR
select CLKSRC_OF
select COMMON_CLK
select GENERIC_CLOCKEVENTS
select MIGHT_HAVE_PCI
select MULTI_IRQ_HANDLER
select SPARSE_IRQ
select USE_OF
config ARM_SINGLE_ARMV7M
bool "ARMv7-M based platforms (Cortex-M0/M3/M4)"
depends on !MMU
select ARCH_WANT_OPTIONAL_GPIOLIB
select ARM_NVIC
select AUTO_ZRELADDR
select CLKSRC_OF
select COMMON_CLK
select CPU_V7M
select GENERIC_CLOCKEVENTS
select NO_IOPORT_MAP
select SPARSE_IRQ
select USE_OF
config ARCH_REALVIEW
bool "ARM Ltd. RealView family"
select ARCH_WANT_OPTIONAL_GPIOLIB
select ARM_AMBA
select ARM_TIMER_SP804
select COMMON_CLK
select COMMON_CLK_VERSATILE
select GENERIC_CLOCKEVENTS
select GPIO_PL061 if GPIOLIB
select ICST
select NEED_MACH_MEMORY_H
select PLAT_VERSATILE
select PLAT_VERSATILE_SCHED_CLOCK
help
This enables support for ARM Ltd RealView boards.
config ARCH_VERSATILE
bool "ARM Ltd. Versatile family"
select ARCH_WANT_OPTIONAL_GPIOLIB
select ARM_AMBA
select ARM_TIMER_SP804
select ARM_VIC
select CLKDEV_LOOKUP
select GENERIC_CLOCKEVENTS
select HAVE_MACH_CLKDEV
select ICST
select PLAT_VERSATILE
select PLAT_VERSATILE_CLOCK
select PLAT_VERSATILE_SCHED_CLOCK
select VERSATILE_FPGA_IRQ
help
This enables support for ARM Ltd Versatile board.
config ARCH_CLPS711X
bool "Cirrus Logic CLPS711x/EP721x/EP731x-based"
select ARCH_REQUIRE_GPIOLIB
select AUTO_ZRELADDR
select CLKSRC_MMIO
select COMMON_CLK
select CPU_ARM720T
select GENERIC_CLOCKEVENTS
select MFD_SYSCON
select SOC_BUS
help
Support for Cirrus Logic 711x/721x/731x based boards.
config ARCH_GEMINI
bool "Cortina Systems Gemini"
select ARCH_REQUIRE_GPIOLIB
select CLKSRC_MMIO
select CPU_FA526
select GENERIC_CLOCKEVENTS
help
Support for the Cortina Systems Gemini family SoCs
config ARCH_EBSA110
bool "EBSA-110"
select ARCH_USES_GETTIMEOFFSET
select CPU_SA110
select ISA
select NEED_MACH_IO_H
select NEED_MACH_MEMORY_H
select NO_IOPORT_MAP
help
This is an evaluation board for the StrongARM processor available
from Digital. It has limited hardware on-board, including an
Ethernet interface, two PCMCIA sockets, two serial ports and a
parallel port.
config ARCH_EP93XX
bool "EP93xx-based"
select ARCH_HAS_HOLES_MEMORYMODEL
select ARCH_REQUIRE_GPIOLIB
select ARM_AMBA
select ARM_PATCH_PHYS_VIRT
select ARM_VIC
select AUTO_ZRELADDR
select CLKDEV_LOOKUP
select CLKSRC_MMIO
select CPU_ARM920T
select GENERIC_CLOCKEVENTS
help
This enables support for the Cirrus EP93xx series of CPUs.
config ARCH_FOOTBRIDGE
bool "FootBridge"
select CPU_SA110
select FOOTBRIDGE
select GENERIC_CLOCKEVENTS
select HAVE_IDE
select NEED_MACH_IO_H if !MMU
select NEED_MACH_MEMORY_H
help
Support for systems based on the DC21285 companion chip
("FootBridge"), such as the Simtec CATS and the Rebel NetWinder.
config ARCH_NETX
bool "Hilscher NetX based"
select ARM_VIC
select CLKSRC_MMIO
select CPU_ARM926T
select GENERIC_CLOCKEVENTS
help
This enables support for systems based on the Hilscher NetX Soc
config ARCH_IOP13XX
bool "IOP13xx-based"
depends on MMU
select CPU_XSC3
select NEED_MACH_MEMORY_H
select NEED_RET_TO_USER
select PCI
select PLAT_IOP
select VMSPLIT_1G
select SPARSE_IRQ
help
Support for Intel's IOP13XX (XScale) family of processors.
config ARCH_IOP32X
bool "IOP32x-based"
depends on MMU
select ARCH_REQUIRE_GPIOLIB
select CPU_XSCALE
select GPIO_IOP
select NEED_RET_TO_USER
select PCI
select PLAT_IOP
help
Support for Intel's 80219 and IOP32X (XScale) family of
processors.
config ARCH_IOP33X
bool "IOP33x-based"
depends on MMU
select ARCH_REQUIRE_GPIOLIB
select CPU_XSCALE
select GPIO_IOP
select NEED_RET_TO_USER
select PCI
select PLAT_IOP
help
Support for Intel's IOP33X (XScale) family of processors.
config ARCH_IXP4XX
bool "IXP4xx-based"
depends on MMU
select ARCH_HAS_DMA_SET_COHERENT_MASK
select ARCH_REQUIRE_GPIOLIB
select ARCH_SUPPORTS_BIG_ENDIAN
select CLKSRC_MMIO
select CPU_XSCALE
select DMABOUNCE if PCI
select GENERIC_CLOCKEVENTS
select MIGHT_HAVE_PCI
select NEED_MACH_IO_H
select USB_EHCI_BIG_ENDIAN_DESC
select USB_EHCI_BIG_ENDIAN_MMIO
help
Support for Intel's IXP4XX (XScale) family of processors.
config ARCH_DOVE
bool "Marvell Dove"
select ARCH_REQUIRE_GPIOLIB
select CPU_PJ4
select GENERIC_CLOCKEVENTS
select MIGHT_HAVE_PCI
select MVEBU_MBUS
select PINCTRL
select PINCTRL_DOVE
select PLAT_ORION_LEGACY
help
Support for the Marvell Dove SoC 88AP510
config ARCH_MV78XX0
bool "Marvell MV78xx0"
select ARCH_REQUIRE_GPIOLIB
select CPU_FEROCEON
select GENERIC_CLOCKEVENTS
select MVEBU_MBUS
select PCI
select PLAT_ORION_LEGACY
help
Support for the following Marvell MV78xx0 series SoCs:
MV781x0, MV782x0.
config ARCH_ORION5X
bool "Marvell Orion"
depends on MMU
select ARCH_REQUIRE_GPIOLIB
select CPU_FEROCEON
select GENERIC_CLOCKEVENTS
select MVEBU_MBUS
select PCI
select PLAT_ORION_LEGACY
select MULTI_IRQ_HANDLER
help
Support for the following Marvell Orion 5x series SoCs:
Orion-1 (5181), Orion-VoIP (5181L), Orion-NAS (5182),
Orion-2 (5281), Orion-1-90 (6183).
config ARCH_MMP
bool "Marvell PXA168/910/MMP2"
depends on MMU
select ARCH_REQUIRE_GPIOLIB
select CLKDEV_LOOKUP
select GENERIC_ALLOCATOR
select GENERIC_CLOCKEVENTS
select GPIO_PXA
select IRQ_DOMAIN
select MULTI_IRQ_HANDLER
select PINCTRL
select PLAT_PXA
select SPARSE_IRQ
help
Support for Marvell's PXA168/PXA910(MMP) and MMP2 processor line.
config ARCH_KS8695
bool "Micrel/Kendin KS8695"
select ARCH_REQUIRE_GPIOLIB
select CLKSRC_MMIO
select CPU_ARM922T
select GENERIC_CLOCKEVENTS
select NEED_MACH_MEMORY_H
help
Support for Micrel/Kendin KS8695 "Centaur" (ARM922T) based
System-on-Chip devices.
config ARCH_W90X900
bool "Nuvoton W90X900 CPU"
select ARCH_REQUIRE_GPIOLIB
select CLKDEV_LOOKUP
select CLKSRC_MMIO
select CPU_ARM926T
select GENERIC_CLOCKEVENTS
help
Support for Nuvoton (Winbond logic dept.) ARM9 processor,
At present, the w90x900 has been renamed nuc900, regarding
the ARM series product line, you can login the following
link address to know more.
<http://www.nuvoton.com/hq/enu/ProductAndSales/ProductLines/
ConsumerElectronicsIC/ARMMicrocontroller/ARMMicrocontroller>
config ARCH_LPC32XX
bool "NXP LPC32XX"
select ARCH_REQUIRE_GPIOLIB
select ARM_AMBA
select CLKDEV_LOOKUP
select CLKSRC_MMIO
select CPU_ARM926T
select GENERIC_CLOCKEVENTS
select HAVE_IDE
select USE_OF
help
Support for the NXP LPC32XX family of processors
config ARCH_PXA
bool "PXA2xx/PXA3xx-based"
depends on MMU
select ARCH_MTD_XIP
select ARCH_REQUIRE_GPIOLIB
select ARM_CPU_SUSPEND if PM
select AUTO_ZRELADDR
select COMMON_CLK
select CLKDEV_LOOKUP
select CLKSRC_MMIO
select CLKSRC_OF
select GENERIC_CLOCKEVENTS
select GPIO_PXA
select HAVE_IDE
select IRQ_DOMAIN
select MULTI_IRQ_HANDLER
select PLAT_PXA
select SPARSE_IRQ
help
Support for Intel/Marvell's PXA2xx/PXA3xx processor line.
config ARCH_QCOM
bool "Qualcomm MSM (non-multiplatform)"
select ARCH_REQUIRE_GPIOLIB
select CPU_V7
select AUTO_ZRELADDR
select HAVE_SMP
select CLKDEV_LOOKUP
select GENERIC_CLOCKEVENTS
select GENERIC_ALLOCATOR
select ARM_GIC
select ARM_PATCH_PHYS_VIRT
select ARM_HAS_SG_CHAIN
select ARCH_HAS_OPP
select SOC_BUS
select MULTI_IRQ_HANDLER
select PM_OPP
select SPARSE_IRQ
select USE_OF
select PINCTRL
select ARCH_WANT_KMAP_ATOMIC_FLUSH
help
Support for Qualcomm MSM/QSD based systems. This runs on the
apps processor of the MSM/QSD and depends on a shared memory
interface to the modem processor which runs the baseband
stack and controls some vital subsystems
(clock and power control, etc).
config ARCH_RPC
bool "RiscPC"
depends on MMU
select ARCH_ACORN
select ARCH_MAY_HAVE_PC_FDC
select ARCH_SPARSEMEM_ENABLE
select ARCH_USES_GETTIMEOFFSET
select CPU_SA110
select FIQ
select HAVE_IDE
select HAVE_PATA_PLATFORM
select ISA_DMA_API
select NEED_MACH_IO_H
select NEED_MACH_MEMORY_H
select NO_IOPORT_MAP
select VIRT_TO_BUS
help
On the Acorn Risc-PC, Linux can support the internal IDE disk and
CD-ROM interface, serial and parallel port, and the floppy drive.
config ARCH_SA1100
bool "SA1100-based"
select ARCH_MTD_XIP
select ARCH_REQUIRE_GPIOLIB
select ARCH_SPARSEMEM_ENABLE
select CLKDEV_LOOKUP
select CLKSRC_MMIO
select CPU_FREQ
select CPU_SA1100
select GENERIC_CLOCKEVENTS
select HAVE_IDE
select IRQ_DOMAIN
select ISA
select MULTI_IRQ_HANDLER
select NEED_MACH_MEMORY_H
select SPARSE_IRQ
help
Support for StrongARM 11x0 based boards.
config ARCH_S3C24XX
bool "Samsung S3C24XX SoCs"
select ARCH_REQUIRE_GPIOLIB
select ATAGS
select CLKDEV_LOOKUP
select CLKSRC_SAMSUNG_PWM
select GENERIC_CLOCKEVENTS
select GPIO_SAMSUNG
select HAVE_S3C2410_I2C if I2C
select HAVE_S3C2410_WATCHDOG if WATCHDOG
select HAVE_S3C_RTC if RTC_CLASS
select MULTI_IRQ_HANDLER
select NEED_MACH_IO_H
select S3C2410_WATCHDOG
select SAMSUNG_ATAGS
select WATCHDOG
help
Samsung S3C2410, S3C2412, S3C2413, S3C2416, S3C2440, S3C2442, S3C2443
and S3C2450 SoCs based systems, such as the Simtec Electronics BAST
(<http://www.simtec.co.uk/products/EB110ITX/>), the IPAQ 1940 or the
Samsung SMDK2410 development board (and derivatives).
config ARCH_S3C64XX
bool "Samsung S3C64XX"
select ARCH_REQUIRE_GPIOLIB
select ARM_AMBA
select ARM_VIC
select ATAGS
select CLKDEV_LOOKUP
select CLKSRC_SAMSUNG_PWM
select COMMON_CLK_SAMSUNG
select CPU_V6K
select GENERIC_CLOCKEVENTS
select GPIO_SAMSUNG
select HAVE_S3C2410_I2C if I2C
select HAVE_S3C2410_WATCHDOG if WATCHDOG
select HAVE_TCM
select NO_IOPORT_MAP
select PLAT_SAMSUNG
select PM_GENERIC_DOMAINS if PM
select S3C_DEV_NAND
select S3C_GPIO_TRACK
select SAMSUNG_ATAGS
select SAMSUNG_WAKEMASK
select SAMSUNG_WDT_RESET
help
Samsung S3C64XX series based systems
config ARCH_DAVINCI
bool "TI DaVinci"
select ARCH_HAS_HOLES_MEMORYMODEL
select ARCH_REQUIRE_GPIOLIB
select CLKDEV_LOOKUP
select GENERIC_ALLOCATOR
select GENERIC_CLOCKEVENTS
select GENERIC_IRQ_CHIP
select HAVE_IDE
select USE_OF
select ZONE_DMA
help
Support for TI's DaVinci platform.
config ARCH_OMAP1
bool "TI OMAP1"
depends on MMU
select ARCH_HAS_HOLES_MEMORYMODEL
select ARCH_OMAP
select ARCH_REQUIRE_GPIOLIB
select CLKDEV_LOOKUP
select CLKSRC_MMIO
select GENERIC_CLOCKEVENTS
select GENERIC_IRQ_CHIP
select HAVE_IDE
select IRQ_DOMAIN
select MULTI_IRQ_HANDLER
select NEED_MACH_IO_H if PCCARD
select NEED_MACH_MEMORY_H
select SPARSE_IRQ
help
Support for older TI OMAP1 (omap7xx, omap15xx or omap16xx)
endchoice
menu "Multiple platform selection"
depends on ARCH_MULTIPLATFORM
comment "CPU Core family selection"
config ARCH_MULTI_V4
bool "ARMv4 based platforms (FA526)"
depends on !ARCH_MULTI_V6_V7
select ARCH_MULTI_V4_V5
select CPU_FA526
config ARCH_MULTI_V4T
bool "ARMv4T based platforms (ARM720T, ARM920T, ...)"
depends on !ARCH_MULTI_V6_V7
select ARCH_MULTI_V4_V5
select CPU_ARM920T if !(CPU_ARM7TDMI || CPU_ARM720T || \
CPU_ARM740T || CPU_ARM9TDMI || CPU_ARM922T || \
CPU_ARM925T || CPU_ARM940T)
config ARCH_MULTI_V5
bool "ARMv5 based platforms (ARM926T, XSCALE, PJ1, ...)"
depends on !ARCH_MULTI_V6_V7
select ARCH_MULTI_V4_V5
select CPU_ARM926T if !(CPU_ARM946E || CPU_ARM1020 || \
CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || \
CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_FEROCEON)
config ARCH_MULTI_V4_V5
bool
config ARCH_MULTI_V6
bool "ARMv6 based platforms (ARM11)"
select ARCH_MULTI_V6_V7
select CPU_V6K
config ARCH_MULTI_V7
bool "ARMv7 based platforms (Cortex-A, PJ4, Scorpion, Krait)"
default y
select ARCH_MULTI_V6_V7
select CPU_V7
select HAVE_SMP
config ARCH_MULTI_V6_V7
bool
select MIGHT_HAVE_CACHE_L2X0
config ARCH_MULTI_CPU_AUTO
def_bool !(ARCH_MULTI_V4 || ARCH_MULTI_V4T || ARCH_MULTI_V6_V7)
select ARCH_MULTI_V5
endmenu
config ARCH_VIRT
bool "Dummy Virtual Machine" if ARCH_MULTI_V7
select ARM_AMBA
select ARM_GIC
select ARM_GIC_V3
select ARM_PSCI
select HAVE_ARM_ARCH_TIMER
#
# This is sorted alphabetically by mach-* pathname. However, plat-*
# Kconfigs may be included either alphabetically (according to the
# plat- suffix) or along side the corresponding mach-* source.
#
source "arch/arm/mach-mvebu/Kconfig"
source "arch/arm/mach-alpine/Kconfig"
source "arch/arm/mach-asm9260/Kconfig"
source "arch/arm/mach-at91/Kconfig"
source "arch/arm/mach-axxia/Kconfig"
source "arch/arm/mach-bcm/Kconfig"
source "arch/arm/mach-berlin/Kconfig"
source "arch/arm/mach-clps711x/Kconfig"
source "arch/arm/mach-cns3xxx/Kconfig"
source "arch/arm/mach-davinci/Kconfig"
source "arch/arm/mach-digicolor/Kconfig"
source "arch/arm/mach-dove/Kconfig"
source "arch/arm/mach-ep93xx/Kconfig"
source "arch/arm/mach-footbridge/Kconfig"
source "arch/arm/mach-gemini/Kconfig"
source "arch/arm/mach-highbank/Kconfig"
source "arch/arm/mach-hisi/Kconfig"
source "arch/arm/mach-integrator/Kconfig"
source "arch/arm/mach-iop32x/Kconfig"
source "arch/arm/mach-iop33x/Kconfig"
source "arch/arm/mach-iop13xx/Kconfig"
source "arch/arm/mach-ixp4xx/Kconfig"
source "arch/arm/mach-keystone/Kconfig"
source "arch/arm/mach-ks8695/Kconfig"
source "arch/arm/mach-meson/Kconfig"
source "arch/arm/mach-moxart/Kconfig"
source "arch/arm/mach-mv78xx0/Kconfig"
source "arch/arm/mach-imx/Kconfig"
source "arch/arm/mach-mediatek/Kconfig"
source "arch/arm/mach-mxs/Kconfig"
source "arch/arm/mach-netx/Kconfig"
source "arch/arm/mach-nomadik/Kconfig"
source "arch/arm/mach-nspire/Kconfig"
source "arch/arm/plat-omap/Kconfig"
source "arch/arm/mach-omap1/Kconfig"
source "arch/arm/mach-omap2/Kconfig"
source "arch/arm/mach-orion5x/Kconfig"
source "arch/arm/mach-picoxcell/Kconfig"
source "arch/arm/mach-pxa/Kconfig"
source "arch/arm/plat-pxa/Kconfig"
source "arch/arm/mach-mmp/Kconfig"
source "arch/arm/mach-qcom/Kconfig"
source "arch/arm/mach-realview/Kconfig"
source "arch/arm/mach-rockchip/Kconfig"
source "arch/arm/mach-sa1100/Kconfig"
source "arch/arm/mach-socfpga/Kconfig"
source "arch/arm/mach-spear/Kconfig"
source "arch/arm/mach-sti/Kconfig"
source "arch/arm/mach-s3c24xx/Kconfig"
source "arch/arm/mach-s3c64xx/Kconfig"
source "arch/arm/mach-s5pv210/Kconfig"
source "arch/arm/mach-exynos/Kconfig"
source "arch/arm/plat-samsung/Kconfig"
source "arch/arm/mach-shmobile/Kconfig"
source "arch/arm/mach-sunxi/Kconfig"
source "arch/arm/mach-prima2/Kconfig"
source "arch/arm/mach-tegra/Kconfig"
source "arch/arm/mach-u300/Kconfig"
source "arch/arm/mach-uniphier/Kconfig"
source "arch/arm/mach-ux500/Kconfig"
source "arch/arm/mach-versatile/Kconfig"
source "arch/arm/mach-vexpress/Kconfig"
source "arch/arm/plat-versatile/Kconfig"
source "arch/arm/mach-vt8500/Kconfig"
source "arch/arm/mach-w90x900/Kconfig"
source "arch/arm/mach-zx/Kconfig"
source "arch/arm/mach-zynq/Kconfig"
# ARMv7-M architecture
config ARCH_EFM32
bool "Energy Micro efm32"
depends on ARM_SINGLE_ARMV7M
select ARCH_REQUIRE_GPIOLIB
help
Support for Energy Micro's (now Silicon Labs) efm32 Giant Gecko
processors.
config ARCH_LPC18XX
bool "NXP LPC18xx/LPC43xx"
depends on ARM_SINGLE_ARMV7M
select ARCH_HAS_RESET_CONTROLLER
select ARM_AMBA
select CLKSRC_LPC32XX
select PINCTRL
help
Support for NXP's LPC18xx Cortex-M3 and LPC43xx Cortex-M4
high performance microcontrollers.
config ARCH_STM32
bool "STMicrolectronics STM32"
depends on ARM_SINGLE_ARMV7M
select ARCH_HAS_RESET_CONTROLLER
select ARMV7M_SYSTICK
select CLKSRC_STM32
select RESET_CONTROLLER
help
Support for STMicroelectronics STM32 processors.
# Definitions to make life easier
config ARCH_ACORN
bool
config PLAT_IOP
bool
select GENERIC_CLOCKEVENTS
config PLAT_ORION
bool
select CLKSRC_MMIO
select COMMON_CLK
select GENERIC_IRQ_CHIP
select IRQ_DOMAIN
config PLAT_ORION_LEGACY
bool
select PLAT_ORION
config PLAT_PXA
bool
config PLAT_VERSATILE
bool
source "arch/arm/firmware/Kconfig"
source arch/arm/mm/Kconfig
config IWMMXT
bool "Enable iWMMXt support"
depends on CPU_XSCALE || CPU_XSC3 || CPU_MOHAWK || CPU_PJ4 || CPU_PJ4B
default y if PXA27x || PXA3xx || ARCH_MMP || CPU_PJ4 || CPU_PJ4B
help
Enable support for iWMMXt context switching at run time if
running on a CPU that supports it.
config MULTI_IRQ_HANDLER
bool
help
Allow each machine to specify it's own IRQ handler at run time.
if !MMU
source "arch/arm/Kconfig-nommu"
endif
config PJ4B_ERRATA_4742
bool "PJ4B Errata 4742: IDLE Wake Up Commands can Cause the CPU Core to Cease Operation"
depends on CPU_PJ4B && MACH_ARMADA_370
default y
help
When coming out of either a Wait for Interrupt (WFI) or a Wait for
Event (WFE) IDLE states, a specific timing sensitivity exists between
the retiring WFI/WFE instructions and the newly issued subsequent
instructions. This sensitivity can result in a CPU hang scenario.
Workaround:
The software must insert either a Data Synchronization Barrier (DSB)
or Data Memory Barrier (DMB) command immediately after the WFI/WFE
instruction
config ARM_ERRATA_326103
bool "ARM errata: FSR write bit incorrect on a SWP to read-only memory"
depends on CPU_V6
help
Executing a SWP instruction to read-only memory does not set bit 11
of the FSR on the ARM 1136 prior to r1p0. This causes the kernel to
treat the access as a read, preventing a COW from occurring and
causing the faulting task to livelock.
config ARM_ERRATA_411920
bool "ARM errata: Invalidation of the Instruction Cache operation can fail"
depends on CPU_V6 || CPU_V6K
help
Invalidation of the Instruction Cache operation can
fail. This erratum is present in 1136 (before r1p4), 1156 and 1176.
It does not affect the MPCore. This option enables the ARM Ltd.
recommended workaround.
config ARM_ERRATA_430973
bool "ARM errata: Stale prediction on replaced interworking branch"
depends on CPU_V7
help
This option enables the workaround for the 430973 Cortex-A8
r1p* erratum. If a code sequence containing an ARM/Thumb
interworking branch is replaced with another code sequence at the
same virtual address, whether due to self-modifying code or virtual
to physical address re-mapping, Cortex-A8 does not recover from the
stale interworking branch prediction. This results in Cortex-A8
executing the new code sequence in the incorrect ARM or Thumb state.
The workaround enables the BTB/BTAC operations by setting ACTLR.IBE
and also flushes the branch target cache at every context switch.
Note that setting specific bits in the ACTLR register may not be
available in non-secure mode.
config ARM_ERRATA_458693
bool "ARM errata: Processor deadlock when a false hazard is created"
depends on CPU_V7
depends on !ARCH_MULTIPLATFORM
help
This option enables the workaround for the 458693 Cortex-A8 (r2p0)
erratum. For very specific sequences of memory operations, it is
possible for a hazard condition intended for a cache line to instead
be incorrectly associated with a different cache line. This false
hazard might then cause a processor deadlock. The workaround enables
the L1 caching of the NEON accesses and disables the PLD instruction
in the ACTLR register. Note that setting specific bits in the ACTLR
register may not be available in non-secure mode.
config ARM_ERRATA_460075
bool "ARM errata: Data written to the L2 cache can be overwritten with stale data"
depends on CPU_V7
depends on !ARCH_MULTIPLATFORM
help
This option enables the workaround for the 460075 Cortex-A8 (r2p0)
erratum. Any asynchronous access to the L2 cache may encounter a
situation in which recent store transactions to the L2 cache are lost
and overwritten with stale memory contents from external memory. The
workaround disables the write-allocate mode for the L2 cache via the
ACTLR register. Note that setting specific bits in the ACTLR register
may not be available in non-secure mode.
config ARM_ERRATA_742230
bool "ARM errata: DMB operation may be faulty"
depends on CPU_V7 && SMP
depends on !ARCH_MULTIPLATFORM
help
This option enables the workaround for the 742230 Cortex-A9
(r1p0..r2p2) erratum. Under rare circumstances, a DMB instruction
between two write operations may not ensure the correct visibility
ordering of the two writes. This workaround sets a specific bit in
the diagnostic register of the Cortex-A9 which causes the DMB
instruction to behave as a DSB, ensuring the correct behaviour of
the two writes.
config ARM_ERRATA_742231
bool "ARM errata: Incorrect hazard handling in the SCU may lead to data corruption"
depends on CPU_V7 && SMP
depends on !ARCH_MULTIPLATFORM
help
This option enables the workaround for the 742231 Cortex-A9
(r2p0..r2p2) erratum. Under certain conditions, specific to the
Cortex-A9 MPCore micro-architecture, two CPUs working in SMP mode,
accessing some data located in the same cache line, may get corrupted
data due to bad handling of the address hazard when the line gets
replaced from one of the CPUs at the same time as another CPU is
accessing it. This workaround sets specific bits in the diagnostic
register of the Cortex-A9 which reduces the linefill issuing
capabilities of the processor.
config ARM_ERRATA_643719
bool "ARM errata: LoUIS bit field in CLIDR register is incorrect"
depends on CPU_V7 && SMP
default y
help
This option enables the workaround for the 643719 Cortex-A9 (prior to
r1p0) erratum. On affected cores the LoUIS bit field of the CLIDR
register returns zero when it should return one. The workaround
corrects this value, ensuring cache maintenance operations which use
it behave as intended and avoiding data corruption.
config ARM_ERRATA_720789
bool "ARM errata: TLBIASIDIS and TLBIMVAIS operations can broadcast a faulty ASID"
depends on CPU_V7
help
This option enables the workaround for the 720789 Cortex-A9 (prior to
r2p0) erratum. A faulty ASID can be sent to the other CPUs for the
broadcasted CP15 TLB maintenance operations TLBIASIDIS and TLBIMVAIS.
As a consequence of this erratum, some TLB entries which should be
invalidated are not, resulting in an incoherency in the system page
tables. The workaround changes the TLB flushing routines to invalidate
entries regardless of the ASID.
config ARM_ERRATA_743622
bool "ARM errata: Faulty hazard checking in the Store Buffer may lead to data corruption"
depends on CPU_V7
depends on !ARCH_MULTIPLATFORM
help
This option enables the workaround for the 743622 Cortex-A9
(r2p*) erratum. Under very rare conditions, a faulty
optimisation in the Cortex-A9 Store Buffer may lead to data
corruption. This workaround sets a specific bit in the diagnostic
register of the Cortex-A9 which disables the Store Buffer
optimisation, preventing the defect from occurring. This has no
visible impact on the overall performance or power consumption of the
processor.
config ARM_ERRATA_751472
bool "ARM errata: Interrupted ICIALLUIS may prevent completion of broadcasted operation"
depends on CPU_V7
depends on !ARCH_MULTIPLATFORM
help
This option enables the workaround for the 751472 Cortex-A9 (prior
to r3p0) erratum. An interrupted ICIALLUIS operation may prevent the
completion of a following broadcasted operation if the second
operation is received by a CPU before the ICIALLUIS has completed,
potentially leading to corrupted entries in the cache or TLB.
config ARM_ERRATA_754322
bool "ARM errata: possible faulty MMU translations following an ASID switch"
depends on CPU_V7
help
This option enables the workaround for the 754322 Cortex-A9 (r2p*,
r3p*) erratum. A speculative memory access may cause a page table walk
which starts prior to an ASID switch but completes afterwards. This
can populate the micro-TLB with a stale entry which may be hit with
the new ASID. This workaround places two dsb instructions in the mm
switching code so that no page table walks can cross the ASID switch.
config ARM_ERRATA_754327
bool "ARM errata: no automatic Store Buffer drain"
depends on CPU_V7 && SMP
help
This option enables the workaround for the 754327 Cortex-A9 (prior to
r2p0) erratum. The Store Buffer does not have any automatic draining
mechanism and therefore a livelock may occur if an external agent
continuously polls a memory location waiting to observe an update.
This workaround defines cpu_relax() as smp_mb(), preventing correctly
written polling loops from denying visibility of updates to memory.
config ARM_ERRATA_364296
bool "ARM errata: Possible cache data corruption with hit-under-miss enabled"
depends on CPU_V6
help
This options enables the workaround for the 364296 ARM1136
r0p2 erratum (possible cache data corruption with
hit-under-miss enabled). It sets the undocumented bit 31 in
the auxiliary control register and the FI bit in the control
register, thus disabling hit-under-miss without putting the
processor into full low interrupt latency mode. ARM11MPCore
is not affected.
config ARM_ERRATA_764369
bool "ARM errata: Data cache line maintenance operation by MVA may not succeed"
depends on CPU_V7 && SMP
help
This option enables the workaround for erratum 764369
affecting Cortex-A9 MPCore with two or more processors (all
current revisions). Under certain timing circumstances, a data
cache line maintenance operation by MVA targeting an Inner
Shareable memory region may fail to proceed up to either the
Point of Coherency or to the Point of Unification of the
system. This workaround adds a DSB instruction before the
relevant cache maintenance functions and sets a specific bit
in the diagnostic control register of the SCU.
config ARM_ERRATA_775420
bool "ARM errata: A data cache maintenance operation which aborts, might lead to deadlock"
depends on CPU_V7
help
This option enables the workaround for the 775420 Cortex-A9 (r2p2,
r2p6,r2p8,r2p10,r3p0) erratum. In case a date cache maintenance
operation aborts with MMU exception, it might cause the processor
to deadlock. This workaround puts DSB before executing ISB if
an abort may occur on cache maintenance.
config ARM_ERRATA_798181
bool "ARM errata: TLBI/DSB failure on Cortex-A15"
depends on CPU_V7 && SMP
help
On Cortex-A15 (r0p0..r3p2) the TLBI*IS/DSB operations are not
adequately shooting down all use of the old entries. This
option enables the Linux kernel workaround for this erratum
which sends an IPI to the CPUs that are running the same ASID
as the one being invalidated.
config ARM_ERRATA_773022
bool "ARM errata: incorrect instructions may be executed from loop buffer"
depends on CPU_V7
help
This option enables the workaround for the 773022 Cortex-A15
(up to r0p4) erratum. In certain rare sequences of code, the
loop buffer may deliver incorrect instructions. This
workaround disables the loop buffer to avoid the erratum.
endmenu
source "arch/arm/common/Kconfig"
menu "Bus support"
config ISA
bool
help
Find out whether you have ISA slots on your motherboard. ISA is the
name of a bus system, i.e. the way the CPU talks to the other stuff
inside your box. Other bus systems are PCI, EISA, MicroChannel
(MCA) or VESA. ISA is an older system, now being displaced by PCI;
newer boards don't support it. If you have ISA, say Y, otherwise N.
# Select ISA DMA controller support
config ISA_DMA
bool
select ISA_DMA_API
# Select ISA DMA interface
config ISA_DMA_API
bool
config PCI
bool "PCI support" if MIGHT_HAVE_PCI
help
Find out whether you have a PCI motherboard. PCI is the name of a
bus system, i.e. the way the CPU talks to the other stuff inside
your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or
VESA. If you have PCI, say Y, otherwise N.
config PCI_DOMAINS
bool
depends on PCI
config PCI_DOMAINS_GENERIC
def_bool PCI_DOMAINS
config PCI_NANOENGINE
bool "BSE nanoEngine PCI support"
depends on SA1100_NANOENGINE
help
Enable PCI on the BSE nanoEngine board.
config PCI_SYSCALL
def_bool PCI
config PCI_HOST_ITE8152
bool
depends on PCI && MACH_ARMCORE
default y
select DMABOUNCE
source "drivers/pci/Kconfig"
source "drivers/pci/pcie/Kconfig"
source "drivers/pcmcia/Kconfig"
endmenu
menu "Kernel Features"
config HAVE_SMP
bool
help
This option should be selected by machines which have an SMP-
capable CPU.
The only effect of this option is to make the SMP-related
options available to the user for configuration.
config SMP
bool "Symmetric Multi-Processing"
depends on CPU_V6K || CPU_V7
depends on GENERIC_CLOCKEVENTS
depends on HAVE_SMP
depends on MMU || ARM_MPU
select IRQ_WORK
help
This enables support for systems with more than one CPU. If you have
a system with only one CPU, say N. If you have a system with more
than one CPU, say Y.
If you say N here, the kernel will run on uni- and multiprocessor
machines, but will use only one CPU of a multiprocessor machine. If
you say Y here, the kernel will run on many, but not all,
uniprocessor machines. On a uniprocessor machine, the kernel
will run faster if you say N here.
See also <file:Documentation/x86/i386/IO-APIC.txt>,
<file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at
<http://tldp.org/HOWTO/SMP-HOWTO.html>.
If you don't know what to do here, say N.
config SMP_ON_UP
bool "Allow booting SMP kernel on uniprocessor systems"
depends on SMP && !XIP_KERNEL && MMU
default y
help
SMP kernels contain instructions which fail on non-SMP processors.
Enabling this option allows the kernel to modify itself to make
these instructions safe. Disabling it allows about 1K of space
savings.
If you don't know what to do here, say Y.
config ARM_CPU_TOPOLOGY
bool "Support cpu topology definition"
depends on SMP && CPU_V7
default y
help
Support ARM cpu topology definition. The MPIDR register defines
affinity between processors which is then used to describe the cpu
topology of an ARM System.
config SCHED_MC
bool "Multi-core scheduler support"
depends on ARM_CPU_TOPOLOGY
help
Multi-core scheduler support improves the CPU scheduler's decision
making when dealing with multi-core CPU chips at a cost of slightly
increased overhead in some places. If unsure say N here.
config SCHED_SMT
bool "SMT scheduler support"
depends on ARM_CPU_TOPOLOGY
help
Improves the CPU scheduler's decision making when dealing with
MultiThreading at a cost of slightly increased overhead in some
places. If unsure say N here.
config HAVE_ARM_SCU
bool
help
This option enables support for the ARM system coherency unit
config HAVE_ARM_ARCH_TIMER
bool "Architected timer support"
depends on CPU_V7
select ARM_ARCH_TIMER
select GENERIC_CLOCKEVENTS
help
This option enables support for the ARM architected timer
config HAVE_ARM_TWD
bool
select CLKSRC_OF if OF
help
This options enables support for the ARM timer and watchdog unit
config MCPM
bool "Multi-Cluster Power Management"
depends on CPU_V7 && SMP
help
This option provides the common power management infrastructure
for (multi-)cluster based systems, such as big.LITTLE based
systems.
config MCPM_QUAD_CLUSTER
bool
depends on MCPM
help
To avoid wasting resources unnecessarily, MCPM only supports up
to 2 clusters by default.
Platforms with 3 or 4 clusters that use MCPM must select this
option to allow the additional clusters to be managed.
config BIG_LITTLE
bool "big.LITTLE support (Experimental)"
depends on CPU_V7 && SMP
select MCPM
help
This option enables support selections for the big.LITTLE
system architecture.
config BL_SWITCHER
bool "big.LITTLE switcher support"
depends on BIG_LITTLE && MCPM && HOTPLUG_CPU && ARM_GIC
select CPU_PM
help
The big.LITTLE "switcher" provides the core functionality to
transparently handle transition between a cluster of A15's
and a cluster of A7's in a big.LITTLE system.
config BL_SWITCHER_DUMMY_IF
tristate "Simple big.LITTLE switcher user interface"
depends on BL_SWITCHER && DEBUG_KERNEL
help
This is a simple and dummy char dev interface to control
the big.LITTLE switcher core code. It is meant for
debugging purposes only.
choice
prompt "Memory split"
depends on MMU
default VMSPLIT_3G
help
Select the desired split between kernel and user memory.
If you are not absolutely sure what you are doing, leave this
option alone!
config VMSPLIT_3G
bool "3G/1G user/kernel split"
config VMSPLIT_3G_OPT
bool "3G/1G user/kernel split (for full 1G low memory)"
config VMSPLIT_2G
bool "2G/2G user/kernel split"
config VMSPLIT_1G
bool "1G/3G user/kernel split"
endchoice
config PAGE_OFFSET
hex
default PHYS_OFFSET if !MMU
default 0x40000000 if VMSPLIT_1G
default 0x80000000 if VMSPLIT_2G
default 0xB0000000 if VMSPLIT_3G_OPT
default 0xC0000000
config NR_CPUS
int "Maximum number of CPUs (2-32)"
range 2 32
depends on SMP
default "4"
config HOTPLUG_CPU
bool "Support for hot-pluggable CPUs"
depends on SMP
select GENERIC_IRQ_MIGRATION
help
Say Y here to experiment with turning CPUs off and on. CPUs
can be controlled through /sys/devices/system/cpu.
config ARM_PSCI
bool "Support for the ARM Power State Coordination Interface (PSCI)"
depends on HAVE_ARM_SMCCC
select ARM_PSCI_FW
help
Say Y here if you want Linux to communicate with system firmware
implementing the PSCI specification for CPU-centric power
management operations described in ARM document number ARM DEN
0022A ("Power State Coordination Interface System Software on
ARM processors").
# The GPIO number here must be sorted by descending number. In case of
# a multiplatform kernel, we just want the highest value required by the
# selected platforms.
config ARCH_NR_GPIO
int
default 1024 if ARCH_BRCMSTB || ARCH_SHMOBILE || ARCH_TEGRA || \
ARCH_ZYNQ || ARCH_QCOM
default 512 if ARCH_EXYNOS || ARCH_KEYSTONE || SOC_OMAP5 || \
SOC_DRA7XX || ARCH_S3C24XX || ARCH_S3C64XX || ARCH_S5PV210
default 416 if ARCH_SUNXI
default 392 if ARCH_U8500
default 352 if ARCH_VT8500
default 288 if ARCH_ROCKCHIP
default 264 if MACH_H4700
default 0
help
Maximum number of GPIOs in the system.
If unsure, leave the default value.
source kernel/Kconfig.preempt
config HZ_FIXED
int
default 200 if ARCH_EBSA110 || ARCH_S3C24XX || \
ARCH_S5PV210 || ARCH_EXYNOS4
default 128 if SOC_AT91RM9200
default 0
choice
depends on HZ_FIXED = 0
prompt "Timer frequency"
config HZ_100
bool "100 Hz"
config HZ_200
bool "200 Hz"
config HZ_250
bool "250 Hz"
config HZ_300
bool "300 Hz"
config HZ_500
bool "500 Hz"
config HZ_1000
bool "1000 Hz"
endchoice
config HZ
int
default HZ_FIXED if HZ_FIXED != 0
default 100 if HZ_100
default 200 if HZ_200
default 250 if HZ_250
default 300 if HZ_300
default 500 if HZ_500
default 1000
config SCHED_HRTICK
def_bool HIGH_RES_TIMERS
config THUMB2_KERNEL
bool "Compile the kernel in Thumb-2 mode" if !CPU_THUMBONLY
depends on (CPU_V7 || CPU_V7M) && !CPU_V6 && !CPU_V6K
default y if CPU_THUMBONLY
select AEABI
select ARM_ASM_UNIFIED
select ARM_UNWIND
help
By enabling this option, the kernel will be compiled in
Thumb-2 mode. A compiler/assembler that understand the unified
ARM-Thumb syntax is needed.
If unsure, say N.
config THUMB2_AVOID_R_ARM_THM_JUMP11
bool "Work around buggy Thumb-2 short branch relocations in gas"
depends on THUMB2_KERNEL && MODULES
default y
help
Various binutils versions can resolve Thumb-2 branches to
locally-defined, preemptible global symbols as short-range "b.n"
branch instructions.
This is a problem, because there's no guarantee the final
destination of the symbol, or any candidate locations for a
trampoline, are within range of the branch. For this reason, the
kernel does not support fixing up the R_ARM_THM_JUMP11 (102)
relocation in modules at all, and it makes little sense to add
support.
The symptom is that the kernel fails with an "unsupported
relocation" error when loading some modules.
Until fixed tools are available, passing
-fno-optimize-sibling-calls to gcc should prevent gcc generating
code which hits this problem, at the cost of a bit of extra runtime
stack usage in some cases.
The problem is described in more detail at:
https://bugs.launchpad.net/binutils-linaro/+bug/725126
Only Thumb-2 kernels are affected.
Unless you are sure your tools don't have this problem, say Y.
config ARM_ASM_UNIFIED
bool
config AEABI
bool "Use the ARM EABI to compile the kernel"
help
This option allows for the kernel to be compiled using the latest
ARM ABI (aka EABI). This is only useful if you are using a user
space environment that is also compiled with EABI.
Since there are major incompatibilities between the legacy ABI and
EABI, especially with regard to structure member alignment, this
option also changes the kernel syscall calling convention to
disambiguate both ABIs and allow for backward compatibility support
(selected with CONFIG_OABI_COMPAT).
To use this you need GCC version 4.0.0 or later.
config OABI_COMPAT
bool "Allow old ABI binaries to run with this kernel (EXPERIMENTAL)"
depends on AEABI && !THUMB2_KERNEL
help
This option preserves the old syscall interface along with the
new (ARM EABI) one. It also provides a compatibility layer to
intercept syscalls that have structure arguments which layout
in memory differs between the legacy ABI and the new ARM EABI
(only for non "thumb" binaries). This option adds a tiny
overhead to all syscalls and produces a slightly larger kernel.
The seccomp filter system will not be available when this is
selected, since there is no way yet to sensibly distinguish
between calling conventions during filtering.
If you know you'll be using only pure EABI user space then you
can say N here. If this option is not selected and you attempt
to execute a legacy ABI binary then the result will be
UNPREDICTABLE (in fact it can be predicted that it won't work
at all). If in doubt say N.
config ARCH_HAS_HOLES_MEMORYMODEL
bool
config ARCH_SPARSEMEM_ENABLE
bool
config ARCH_SPARSEMEM_DEFAULT
def_bool ARCH_SPARSEMEM_ENABLE
config ARCH_SELECT_MEMORY_MODEL
def_bool ARCH_SPARSEMEM_ENABLE
config HAVE_ARCH_PFN_VALID
def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM
config HAVE_GENERIC_RCU_GUP
def_bool y
depends on ARM_LPAE
config HIGHMEM
bool "High Memory Support"
depends on MMU
help
The address space of ARM processors is only 4 Gigabytes large
and it has to accommodate user address space, kernel address
space as well as some memory mapped IO. That means that, if you
have a large amount of physical memory and/or IO, not all of the
memory can be "permanently mapped" by the kernel. The physical
memory that is not permanently mapped is called "high memory".
Depending on the selected kernel/user memory split, minimum
vmalloc space and actual amount of RAM, you may not need this
option which should result in a slightly faster kernel.
If unsure, say n.
config HIGHPTE
bool "Allocate 2nd-level pagetables from highmem" if EXPERT
depends on HIGHMEM
default y
help
The VM uses one page of physical memory for each page table.
For systems with a lot of processes, this can use a lot of
precious low memory, eventually leading to low memory being
consumed by page tables. Setting this option will allow
user-space 2nd level page tables to reside in high memory.
config CPU_SW_DOMAIN_PAN
bool "Enable use of CPU domains to implement privileged no-access"
depends on MMU && !ARM_LPAE
default y
help
Increase kernel security by ensuring that normal kernel accesses
are unable to access userspace addresses. This can help prevent
use-after-free bugs becoming an exploitable privilege escalation
by ensuring that magic values (such as LIST_POISON) will always
fault when dereferenced.
CPUs with low-vector mappings use a best-efforts implementation.
Their lower 1MB needs to remain accessible for the vectors, but
the remainder of userspace will become appropriately inaccessible.
config HW_PERF_EVENTS
def_bool y
depends on ARM_PMU
config SYS_SUPPORTS_HUGETLBFS
def_bool y
depends on ARM_LPAE
config HAVE_ARCH_TRANSPARENT_HUGEPAGE
def_bool y
depends on ARM_LPAE
config ARCH_WANT_GENERAL_HUGETLB
def_bool y
config ARM_MODULE_PLTS
bool "Use PLTs to allow module memory to spill over into vmalloc area"
depends on MODULES
help
Allocate PLTs when loading modules so that jumps and calls whose
targets are too far away for their relative offsets to be encoded
in the instructions themselves can be bounced via veneers in the
module's PLT. This allows modules to be allocated in the generic
vmalloc area after the dedicated module memory area has been
exhausted. The modules will use slightly more memory, but after
rounding up to page size, the actual memory footprint is usually
the same.
Say y if you are getting out of memory errors while loading modules
source "mm/Kconfig"
choice
prompt "Virtual Memory Reclaim"
default ENABLE_VMALLOC_SAVING
help
Select the method of reclaiming virtual memory
config ENABLE_VMALLOC_SAVING
bool "Reclaim memory for each subsystem"
help
Enable this config to reclaim the virtual space belonging
to any subsystem which is expected to have a lifetime of
the entire system. This feature allows lowmem to be non-
contiguous.
config NO_VM_RECLAIM
bool "Do not reclaim memory"
help
Do not reclaim any memory. This might result in less lowmem
and wasting virtual memory space which could otherwise be
reclaimed by using any of the other two config options.
endchoice
config FORCE_MAX_ZONEORDER
int "Maximum zone order"
default "12" if SOC_AM33XX
default "9" if SA1111 || ARCH_EFM32
default "11"
help
The kernel memory allocator divides physically contiguous memory
blocks into "zones", where each zone is a power of two number of
pages. This option selects the largest power of two that the kernel
keeps in the memory allocator. If you need to allocate very large
blocks of physically contiguous memory, then you may need to
increase this value.
This config option is actually maximum order plus one. For example,
a value of 11 means that the largest free memory block is 2^10 pages.
config ALIGNMENT_TRAP
bool
depends on CPU_CP15_MMU
default y if !ARCH_EBSA110
select HAVE_PROC_CPU if PROC_FS
help
ARM processors cannot fetch/store information which is not
naturally aligned on the bus, i.e., a 4 byte fetch must start at an
address divisible by 4. On 32-bit ARM processors, these non-aligned
fetch/store instructions will be emulated in software if you say
here, which has a severe performance impact. This is necessary for
correct operation of some network protocols. With an IP-only
configuration it is safe to say N, otherwise say Y.
config UACCESS_WITH_MEMCPY
bool "Use kernel mem{cpy,set}() for {copy_to,clear}_user()"
depends on MMU
default y if CPU_FEROCEON
help
Implement faster copy_to_user and clear_user methods for CPU
cores where a 8-word STM instruction give significantly higher
memory write throughput than a sequence of individual 32bit stores.
A possible side effect is a slight increase in scheduling latency
between threads sharing the same address space if they invoke
such copy operations with large buffers.
However, if the CPU data cache is using a write-allocate mode,
this option is unlikely to provide any performance gain.
config SECCOMP
bool
prompt "Enable seccomp to safely compute untrusted bytecode"
---help---
This kernel feature is useful for number crunching applications
that may need to compute untrusted bytecode during their
execution. By using pipes or other transports made available to
the process as file descriptors supporting the read/write
syscalls, it's possible to isolate those applications in
their own address space using seccomp. Once seccomp is
enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
and the task is only allowed to execute a few safe syscalls
defined by each seccomp mode.
config SWIOTLB
def_bool y
config IOMMU_HELPER
def_bool SWIOTLB
config XEN_DOM0
def_bool y
depends on XEN
config XEN
bool "Xen guest support on ARM"
depends on ARM && AEABI && OF
depends on CPU_V7 && !CPU_V6
depends on !GENERIC_ATOMIC64
depends on MMU
select ARCH_DMA_ADDR_T_64BIT
select ARM_PSCI
select SWIOTLB_XEN
help
Say Y if you want to run Linux in a Virtual Machine on Xen on ARM.
config ARM_FLUSH_CONSOLE_ON_RESTART
bool "Force flush the console on restart"
help
If the console is locked while the system is rebooted, the messages
in the temporary logbuffer would not have propogated to all the
console drivers. This option forces the console lock to be
released if it failed to be acquired, which will cause all the
pending messages to be flushed.
endmenu
menu "Boot options"
config USE_OF
bool "Flattened Device Tree support"
select IRQ_DOMAIN
select OF
help
Include support for flattened device tree machine descriptions.
config ATAGS
bool "Support for the traditional ATAGS boot data passing" if USE_OF
default y
help
This is the traditional way of passing data to the kernel at boot
time. If you are solely relying on the flattened device tree (or
the ARM_ATAG_DTB_COMPAT option) then you may unselect this option
to remove ATAGS support from your kernel binary. If unsure,
leave this to y.
config DEPRECATED_PARAM_STRUCT
bool "Provide old way to pass kernel parameters"
depends on ATAGS
help
This was deprecated in 2001 and announced to live on for 5 years.
Some old boot loaders still use this way.
config BUILD_ARM_APPENDED_DTB_IMAGE
bool "Build a concatenated zImage/dtb by default"
depends on OF
help
Enabling this option will cause a concatenated zImage and list of
DTBs to be built by default (instead of a standalone zImage.)
The image will built in arch/arm/boot/zImage-dtb
config BUILD_ARM_APPENDED_DTB_IMAGE_NAMES
string "Default dtb names"
depends on BUILD_ARM_APPENDED_DTB_IMAGE
help
Space separated list of names of dtbs to append when
building a concatenated zImage-dtb.
# Compressed boot loader in ROM. Yes, we really want to ask about
# TEXT and BSS so we preserve their values in the config files.
config ZBOOT_ROM_TEXT
hex "Compressed ROM boot loader base address"
default "0"
help
The physical address at which the ROM-able zImage is to be
placed in the target. Platforms which normally make use of
ROM-able zImage formats normally set this to a suitable
value in their defconfig file.
If ZBOOT_ROM is not enabled, this has no effect.
config ZBOOT_ROM_BSS
hex "Compressed ROM boot loader BSS address"
default "0"
help
The base address of an area of read/write memory in the target
for the ROM-able zImage which must be available while the
decompressor is running. It must be large enough to hold the
entire decompressed kernel plus an additional 128 KiB.
Platforms which normally make use of ROM-able zImage formats
normally set this to a suitable value in their defconfig file.
If ZBOOT_ROM is not enabled, this has no effect.
config ZBOOT_ROM
bool "Compressed boot loader in ROM/flash"
depends on ZBOOT_ROM_TEXT != ZBOOT_ROM_BSS
depends on !ARM_APPENDED_DTB && !XIP_KERNEL && !AUTO_ZRELADDR
help
Say Y here if you intend to execute your compressed kernel image
(zImage) directly from ROM or flash. If unsure, say N.
config ARM_APPENDED_DTB
bool "Use appended device tree blob to zImage (EXPERIMENTAL)"
depends on OF
help
With this option, the boot code will look for a device tree binary
(DTB) appended to zImage
(e.g. cat zImage <filename>.dtb > zImage_w_dtb).
This is meant as a backward compatibility convenience for those
systems with a bootloader that can't be upgraded to accommodate
the documented boot protocol using a device tree.
Beware that there is very little in terms of protection against
this option being confused by leftover garbage in memory that might
look like a DTB header after a reboot if no actual DTB is appended
to zImage. Do not leave this option active in a production kernel
if you don't intend to always append a DTB. Proper passing of the
location into r2 of a bootloader provided DTB is always preferable
to this option.
config ARM_ATAG_DTB_COMPAT
bool "Supplement the appended DTB with traditional ATAG information"
depends on ARM_APPENDED_DTB
help
Some old bootloaders can't be updated to a DTB capable one, yet
they provide ATAGs with memory configuration, the ramdisk address,
the kernel cmdline string, etc. Such information is dynamically
provided by the bootloader and can't always be stored in a static
DTB. To allow a device tree enabled kernel to be used with such
bootloaders, this option allows zImage to extract the information
from the ATAG list and store it at run time into the appended DTB.
choice
prompt "Kernel command line type" if ARM_ATAG_DTB_COMPAT
default ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
config ARM_ATAG_DTB_COMPAT_CMDLINE_FROM_BOOTLOADER
bool "Use bootloader kernel arguments if available"
help
Uses the command-line options passed by the boot loader instead of
the device tree bootargs property. If the boot loader doesn't provide
any, the device tree bootargs property will be used.
config ARM_ATAG_DTB_COMPAT_CMDLINE_EXTEND
bool "Extend with bootloader kernel arguments"
help
The command-line arguments provided by the boot loader will be
appended to the the device tree bootargs property.
endchoice
config CMDLINE
string "Default kernel command string"
default ""
help
On some architectures (EBSA110 and CATS), there is currently no way
for the boot loader to pass arguments to the kernel. For these
architectures, you should supply some command-line options at build
time by entering them here. As a minimum, you should specify the
memory size and the root device (e.g., mem=64M root=/dev/nfs).
choice
prompt "Kernel command line type" if CMDLINE != ""
default CMDLINE_FROM_BOOTLOADER
depends on ATAGS
config CMDLINE_FROM_BOOTLOADER
bool "Use bootloader kernel arguments if available"
help
Uses the command-line options passed by the boot loader. If
the boot loader doesn't provide any, the default kernel command
string provided in CMDLINE will be used.
config CMDLINE_EXTEND
bool "Extend bootloader kernel arguments"
help
The command-line arguments provided by the boot loader will be
appended to the default kernel command string.
config CMDLINE_FORCE
bool "Always use the default kernel command string"
help
Always use the default kernel command string, even if the boot
loader passes other arguments to the kernel.
This is useful if you cannot or don't want to change the
command-line options your boot loader passes to the kernel.
endchoice
config XIP_KERNEL
bool "Kernel Execute-In-Place from ROM"
depends on !ARM_LPAE && !ARCH_MULTIPLATFORM
help
Execute-In-Place allows the kernel to run from non-volatile storage
directly addressable by the CPU, such as NOR flash. This saves RAM
space since the text section of the kernel is not loaded from flash
to RAM. Read-write sections, such as the data section and stack,
are still copied to RAM. The XIP kernel is not compressed since
it has to run directly from flash, so it will take more space to
store it. The flash address used to link the kernel object files,
and for storing it, is configuration dependent. Therefore, if you
say Y here, you must know the proper physical address where to
store the kernel image depending on your own flash memory usage.
Also note that the make target becomes "make xipImage" rather than
"make zImage" or "make Image". The final kernel binary to put in
ROM memory will be arch/arm/boot/xipImage.
If unsure, say N.
config XIP_PHYS_ADDR
hex "XIP Kernel Physical Location"
depends on XIP_KERNEL
default "0x00080000"
help
This is the physical address in your flash memory the kernel will
be linked for and stored to. This address is dependent on your
own flash usage.
config KEXEC
bool "Kexec system call (EXPERIMENTAL)"
depends on (!SMP || PM_SLEEP_SMP)
depends on MMU
select KEXEC_CORE
help
kexec is a system call that implements the ability to shutdown your
current kernel, and to start another kernel. It is like a reboot
but it is independent of the system firmware. And like a reboot
you can start any kernel with it, not just Linux.
It is an ongoing process to be certain the hardware in a machine
is properly shutdown, so do not be surprised if this code does not
initially work for you.
config ATAGS_PROC
bool "Export atags in procfs"
depends on ATAGS && KEXEC
default y
help
Should the atags used to boot the kernel be exported in an "atags"
file in procfs. Useful with kexec.
config CRASH_DUMP
bool "Build kdump crash kernel (EXPERIMENTAL)"
help
Generate crash dump after being started by kexec. This should
be normally only set in special crash dump kernels which are
loaded in the main kernel with kexec-tools into a specially
reserved region and then later executed after a crash by
kdump/kexec. The crash dump kernel must be compiled to a
memory address not used by the main kernel
For more details see Documentation/kdump/kdump.txt
config AUTO_ZRELADDR
bool "Auto calculation of the decompressed kernel image address"
help
ZRELADDR is the physical address where the decompressed kernel
image will be placed. If AUTO_ZRELADDR is selected, the address
will be determined at run-time by masking the current IP with
0xf8000000. This assumes the zImage being placed in the first 128MB
from start of memory.
endmenu
menu "CPU Power Management"
source "drivers/cpufreq/Kconfig"
source "drivers/cpuidle/Kconfig"
endmenu
menu "Floating point emulation"
comment "At least one emulation must be selected"
config FPE_NWFPE
bool "NWFPE math emulation"
depends on (!AEABI || OABI_COMPAT) && !THUMB2_KERNEL
---help---
Say Y to include the NWFPE floating point emulator in the kernel.
This is necessary to run most binaries. Linux does not currently
support floating point hardware so you need to say Y here even if
your machine has an FPA or floating point co-processor podule.
You may say N here if you are going to load the Acorn FPEmulator
early in the bootup.
config FPE_NWFPE_XP
bool "Support extended precision"
depends on FPE_NWFPE
help
Say Y to include 80-bit support in the kernel floating-point
emulator. Otherwise, only 32 and 64-bit support is compiled in.
Note that gcc does not generate 80-bit operations by default,
so in most cases this option only enlarges the size of the
floating point emulator without any good reason.
You almost surely want to say N here.
config FPE_FASTFPE
bool "FastFPE math emulation (EXPERIMENTAL)"
depends on (!AEABI || OABI_COMPAT) && !CPU_32v3
---help---
Say Y here to include the FAST floating point emulator in the kernel.
This is an experimental much faster emulator which now also has full
precision for the mantissa. It does not support any exceptions.
It is very simple, and approximately 3-6 times faster than NWFPE.
It should be sufficient for most programs. It may be not suitable
for scientific calculations, but you have to check this for yourself.
If you do not feel you need a faster FP emulation you should better
choose NWFPE.
config VFP
bool "VFP-format floating point maths"
depends on CPU_V6 || CPU_V6K || CPU_ARM926T || CPU_V7 || CPU_FEROCEON
help
Say Y to include VFP support code in the kernel. This is needed
if your hardware includes a VFP unit.
Please see <file:Documentation/arm/VFP/release-notes.txt> for
release notes and additional status information.
Say N if your target does not have VFP hardware.
config VFPv3
bool
depends on VFP
default y if CPU_V7
config NEON
bool "Advanced SIMD (NEON) Extension support"
depends on VFPv3 && CPU_V7
help
Say Y to include support code for NEON, the ARMv7 Advanced SIMD
Extension.
config KERNEL_MODE_NEON
bool "Support for NEON in kernel mode"
depends on NEON && AEABI
help
Say Y to include support for NEON in kernel mode.
endmenu
menu "Userspace binary formats"
source "fs/Kconfig.binfmt"
endmenu
menu "Power management options"
source "kernel/power/Kconfig"
config ARCH_SUSPEND_POSSIBLE
depends on CPU_ARM920T || CPU_ARM926T || CPU_FEROCEON || CPU_SA1100 || \
CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7M || CPU_XSC3 || CPU_XSCALE || CPU_MOHAWK
def_bool y
config ARM_CPU_SUSPEND
def_bool PM_SLEEP || BL_SWITCHER || ARM_PSCI_FW
depends on ARCH_SUSPEND_POSSIBLE
config ARCH_HIBERNATION_POSSIBLE
bool
depends on MMU
default y if ARCH_SUSPEND_POSSIBLE
endmenu
source "net/Kconfig"
source "drivers/Kconfig"
source "drivers/firmware/Kconfig"
source "fs/Kconfig"
source "arch/arm/Kconfig.debug"
source "security/Kconfig"
source "crypto/Kconfig"
if CRYPTO
source "arch/arm/crypto/Kconfig"
endif
source "lib/Kconfig"
source "arch/arm/kvm/Kconfig"
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