Kconfig 15.9 KB
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comment "Processor Type"

config CPU_32
	bool
	default y

# Select CPU types depending on the architecture selected.  This selects
# which CPUs we support in the kernel image, and the compiler instruction
# optimiser behaviour.

# ARM610
config CPU_ARM610
	bool "Support ARM610 processor"
	depends on ARCH_RPC
	select CPU_32v3
	select CPU_CACHE_V3
	select CPU_CACHE_VIVT
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	select CPU_CP15_MMU
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	select CPU_COPY_V3 if MMU
	select CPU_TLB_V3 if MMU
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	help
	  The ARM610 is the successor to the ARM3 processor
	  and was produced by VLSI Technology Inc.

	  Say Y if you want support for the ARM610 processor.
	  Otherwise, say N.

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# ARM7TDMI
config CPU_ARM7TDMI
	bool "Support ARM7TDMI processor"
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	depends on !MMU
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	select CPU_32v4T
	select CPU_ABRT_LV4T
	select CPU_CACHE_V4
	help
	  A 32-bit RISC microprocessor based on the ARM7 processor core
	  which has no memory control unit and cache.

	  Say Y if you want support for the ARM7TDMI processor.
	  Otherwise, say N.

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# ARM710
config CPU_ARM710
	bool "Support ARM710 processor" if !ARCH_CLPS7500 && ARCH_RPC
	default y if ARCH_CLPS7500
	select CPU_32v3
	select CPU_CACHE_V3
	select CPU_CACHE_VIVT
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	select CPU_CP15_MMU
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	select CPU_COPY_V3 if MMU
	select CPU_TLB_V3 if MMU
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	help
	  A 32-bit RISC microprocessor based on the ARM7 processor core
	  designed by Advanced RISC Machines Ltd. The ARM710 is the
	  successor to the ARM610 processor. It was released in
	  July 1994 by VLSI Technology Inc.

	  Say Y if you want support for the ARM710 processor.
	  Otherwise, say N.

# ARM720T
config CPU_ARM720T
	bool "Support ARM720T processor" if !ARCH_CLPS711X && !ARCH_L7200 && !ARCH_CDB89712 && ARCH_INTEGRATOR
	default y if ARCH_CLPS711X || ARCH_L7200 || ARCH_CDB89712 || ARCH_H720X
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	select CPU_32v4T
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	select CPU_ABRT_LV4T
	select CPU_CACHE_V4
	select CPU_CACHE_VIVT
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	select CPU_CP15_MMU
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	select CPU_COPY_V4WT if MMU
	select CPU_TLB_V4WT if MMU
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	help
	  A 32-bit RISC processor with 8kByte Cache, Write Buffer and
	  MMU built around an ARM7TDMI core.

	  Say Y if you want support for the ARM720T processor.
	  Otherwise, say N.

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# ARM740T
config CPU_ARM740T
	bool "Support ARM740T processor" if ARCH_INTEGRATOR
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	depends on !MMU
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	select CPU_32v4T
	select CPU_ABRT_LV4T
	select CPU_CACHE_V3	# although the core is v4t
	select CPU_CP15_MPU
	help
	  A 32-bit RISC processor with 8KB cache or 4KB variants,
	  write buffer and MPU(Protection Unit) built around
	  an ARM7TDMI core.

	  Say Y if you want support for the ARM740T processor.
	  Otherwise, say N.

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# ARM9TDMI
config CPU_ARM9TDMI
	bool "Support ARM9TDMI processor"
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	depends on !MMU
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	select CPU_32v4T
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	select CPU_ABRT_NOMMU
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	select CPU_CACHE_V4
	help
	  A 32-bit RISC microprocessor based on the ARM9 processor core
	  which has no memory control unit and cache.

	  Say Y if you want support for the ARM9TDMI processor.
	  Otherwise, say N.

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# ARM920T
config CPU_ARM920T
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	bool "Support ARM920T processor"
	depends on ARCH_EP93XX || ARCH_INTEGRATOR || CPU_S3C2410 || CPU_S3C2440 || CPU_S3C2442 || ARCH_IMX || ARCH_AAEC2000 || ARCH_AT91RM9200
	default y if CPU_S3C2410 || CPU_S3C2440 || CPU_S3C2442 || ARCH_AT91RM9200
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	select CPU_32v4T
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	select CPU_ABRT_EV4T
	select CPU_CACHE_V4WT
	select CPU_CACHE_VIVT
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	select CPU_CP15_MMU
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	select CPU_COPY_V4WB if MMU
	select CPU_TLB_V4WBI if MMU
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	help
	  The ARM920T is licensed to be produced by numerous vendors,
	  and is used in the Maverick EP9312 and the Samsung S3C2410.

	  More information on the Maverick EP9312 at
	  <http://linuxdevices.com/products/PD2382866068.html>.

	  Say Y if you want support for the ARM920T processor.
	  Otherwise, say N.

# ARM922T
config CPU_ARM922T
	bool "Support ARM922T processor" if ARCH_INTEGRATOR
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	depends on ARCH_LH7A40X || ARCH_INTEGRATOR
	default y if ARCH_LH7A40X
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	select CPU_32v4T
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	select CPU_ABRT_EV4T
	select CPU_CACHE_V4WT
	select CPU_CACHE_VIVT
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	select CPU_CP15_MMU
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	select CPU_COPY_V4WB if MMU
	select CPU_TLB_V4WBI if MMU
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	help
	  The ARM922T is a version of the ARM920T, but with smaller
	  instruction and data caches. It is used in Altera's
	  Excalibur XA device family.

	  Say Y if you want support for the ARM922T processor.
	  Otherwise, say N.

# ARM925T
config CPU_ARM925T
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 	bool "Support ARM925T processor" if ARCH_OMAP1
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 	depends on ARCH_OMAP15XX
 	default y if ARCH_OMAP15XX
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	select CPU_32v4T
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	select CPU_ABRT_EV4T
	select CPU_CACHE_V4WT
	select CPU_CACHE_VIVT
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	select CPU_CP15_MMU
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	select CPU_COPY_V4WB if MMU
	select CPU_TLB_V4WBI if MMU
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 	help
 	  The ARM925T is a mix between the ARM920T and ARM926T, but with
	  different instruction and data caches. It is used in TI's OMAP
 	  device family.

 	  Say Y if you want support for the ARM925T processor.
 	  Otherwise, say N.

# ARM926T
config CPU_ARM926T
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	bool "Support ARM926T processor"
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	depends on ARCH_INTEGRATOR || ARCH_VERSATILE_PB || MACH_VERSATILE_AB || ARCH_OMAP730 || ARCH_OMAP16XX || MACH_REALVIEW_EB || ARCH_PNX4008 || ARCH_NETX || CPU_S3C2412 || ARCH_AT91SAM9260 || ARCH_AT91SAM9261
	default y if ARCH_VERSATILE_PB || MACH_VERSATILE_AB || ARCH_OMAP730 || ARCH_OMAP16XX || ARCH_PNX4008 || ARCH_NETX || CPU_S3C2412 || ARCH_AT91SAM9260 || ARCH_AT91SAM9261
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	select CPU_32v5
	select CPU_ABRT_EV5TJ
	select CPU_CACHE_VIVT
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	select CPU_CP15_MMU
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	select CPU_COPY_V4WB if MMU
	select CPU_TLB_V4WBI if MMU
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	help
	  This is a variant of the ARM920.  It has slightly different
	  instruction sequences for cache and TLB operations.  Curiously,
	  there is no documentation on it at the ARM corporate website.

	  Say Y if you want support for the ARM926T processor.
	  Otherwise, say N.

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# ARM940T
config CPU_ARM940T
	bool "Support ARM940T processor" if ARCH_INTEGRATOR
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	depends on !MMU
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	select CPU_32v4T
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	select CPU_ABRT_NOMMU
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	select CPU_CACHE_VIVT
	select CPU_CP15_MPU
	help
	  ARM940T is a member of the ARM9TDMI family of general-
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	  purpose microprocessors with MPU and separate 4KB
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	  instruction and 4KB data cases, each with a 4-word line
	  length.

	  Say Y if you want support for the ARM940T processor.
	  Otherwise, say N.

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# ARM946E-S
config CPU_ARM946E
	bool "Support ARM946E-S processor" if ARCH_INTEGRATOR
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	depends on !MMU
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	select CPU_32v5
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	select CPU_ABRT_NOMMU
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	select CPU_CACHE_VIVT
	select CPU_CP15_MPU
	help
	  ARM946E-S is a member of the ARM9E-S family of high-
	  performance, 32-bit system-on-chip processor solutions.
	  The TCM and ARMv5TE 32-bit instruction set is supported.

	  Say Y if you want support for the ARM946E-S processor.
	  Otherwise, say N.

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# ARM1020 - needs validating
config CPU_ARM1020
	bool "Support ARM1020T (rev 0) processor"
	depends on ARCH_INTEGRATOR
	select CPU_32v5
	select CPU_ABRT_EV4T
	select CPU_CACHE_V4WT
	select CPU_CACHE_VIVT
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	select CPU_CP15_MMU
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	select CPU_COPY_V4WB if MMU
	select CPU_TLB_V4WBI if MMU
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	help
	  The ARM1020 is the 32K cached version of the ARM10 processor,
	  with an addition of a floating-point unit.

	  Say Y if you want support for the ARM1020 processor.
	  Otherwise, say N.

# ARM1020E - needs validating
config CPU_ARM1020E
	bool "Support ARM1020E processor"
	depends on ARCH_INTEGRATOR
	select CPU_32v5
	select CPU_ABRT_EV4T
	select CPU_CACHE_V4WT
	select CPU_CACHE_VIVT
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	select CPU_CP15_MMU
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	select CPU_COPY_V4WB if MMU
	select CPU_TLB_V4WBI if MMU
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	depends on n

# ARM1022E
config CPU_ARM1022
	bool "Support ARM1022E processor"
	depends on ARCH_INTEGRATOR
	select CPU_32v5
	select CPU_ABRT_EV4T
	select CPU_CACHE_VIVT
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	select CPU_CP15_MMU
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	select CPU_COPY_V4WB if MMU # can probably do better
	select CPU_TLB_V4WBI if MMU
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	help
	  The ARM1022E is an implementation of the ARMv5TE architecture
	  based upon the ARM10 integer core with a 16KiB L1 Harvard cache,
	  embedded trace macrocell, and a floating-point unit.

	  Say Y if you want support for the ARM1022E processor.
	  Otherwise, say N.

# ARM1026EJ-S
config CPU_ARM1026
	bool "Support ARM1026EJ-S processor"
	depends on ARCH_INTEGRATOR
	select CPU_32v5
	select CPU_ABRT_EV5T # But need Jazelle, but EV5TJ ignores bit 10
	select CPU_CACHE_VIVT
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	select CPU_CP15_MMU
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	select CPU_COPY_V4WB if MMU # can probably do better
	select CPU_TLB_V4WBI if MMU
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	help
	  The ARM1026EJ-S is an implementation of the ARMv5TEJ architecture
	  based upon the ARM10 integer core.

	  Say Y if you want support for the ARM1026EJ-S processor.
	  Otherwise, say N.

# SA110
config CPU_SA110
	bool "Support StrongARM(R) SA-110 processor" if !ARCH_EBSA110 && !FOOTBRIDGE && !ARCH_TBOX && !ARCH_SHARK && !ARCH_NEXUSPCI && ARCH_RPC
	default y if ARCH_EBSA110 || FOOTBRIDGE || ARCH_TBOX || ARCH_SHARK || ARCH_NEXUSPCI
	select CPU_32v3 if ARCH_RPC
	select CPU_32v4 if !ARCH_RPC
	select CPU_ABRT_EV4
	select CPU_CACHE_V4WB
	select CPU_CACHE_VIVT
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	select CPU_CP15_MMU
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	select CPU_COPY_V4WB if MMU
	select CPU_TLB_V4WB if MMU
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	help
	  The Intel StrongARM(R) SA-110 is a 32-bit microprocessor and
	  is available at five speeds ranging from 100 MHz to 233 MHz.
	  More information is available at
	  <http://developer.intel.com/design/strong/sa110.htm>.

	  Say Y if you want support for the SA-110 processor.
	  Otherwise, say N.

# SA1100
config CPU_SA1100
	bool
	depends on ARCH_SA1100
	default y
	select CPU_32v4
	select CPU_ABRT_EV4
	select CPU_CACHE_V4WB
	select CPU_CACHE_VIVT
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	select CPU_CP15_MMU
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	select CPU_TLB_V4WB if MMU
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# XScale
config CPU_XSCALE
	bool
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	depends on ARCH_IOP32X || ARCH_IOP33X || ARCH_PXA || ARCH_IXP4XX || ARCH_IXP2000
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	default y
	select CPU_32v5
	select CPU_ABRT_EV5T
	select CPU_CACHE_VIVT
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	select CPU_CP15_MMU
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	select CPU_TLB_V4WBI if MMU
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# XScale Core Version 3
config CPU_XSC3
	bool
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	depends on ARCH_IXP23XX || ARCH_IOP13XX
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	default y
	select CPU_32v5
	select CPU_ABRT_EV5T
	select CPU_CACHE_VIVT
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	select CPU_CP15_MMU
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	select CPU_TLB_V4WBI if MMU
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	select IO_36

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# ARMv6
config CPU_V6
	bool "Support ARM V6 processor"
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	depends on ARCH_INTEGRATOR || MACH_REALVIEW_EB || ARCH_OMAP2
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	select CPU_32v6
	select CPU_ABRT_EV6
	select CPU_CACHE_V6
	select CPU_CACHE_VIPT
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	select CPU_CP15_MMU
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	select CPU_COPY_V6 if MMU
	select CPU_TLB_V6 if MMU
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# ARMv6k
config CPU_32v6K
	bool "Support ARM V6K processor extensions" if !SMP
	depends on CPU_V6
	default y if SMP
	help
	  Say Y here if your ARMv6 processor supports the 'K' extension.
	  This enables the kernel to use some instructions not present
	  on previous processors, and as such a kernel build with this
	  enabled will not boot on processors with do not support these
	  instructions.

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# Figure out what processor architecture version we should be using.
# This defines the compiler instruction set which depends on the machine type.
config CPU_32v3
	bool
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	select TLS_REG_EMUL if SMP || !MMU
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	select NEEDS_SYSCALL_FOR_CMPXCHG if SMP
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config CPU_32v4
	bool
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	select TLS_REG_EMUL if SMP || !MMU
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	select NEEDS_SYSCALL_FOR_CMPXCHG if SMP
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config CPU_32v4T
	bool
	select TLS_REG_EMUL if SMP || !MMU
	select NEEDS_SYSCALL_FOR_CMPXCHG if SMP

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config CPU_32v5
	bool
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	select TLS_REG_EMUL if SMP || !MMU
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	select NEEDS_SYSCALL_FOR_CMPXCHG if SMP
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config CPU_32v6
	bool

# The abort model
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config CPU_ABRT_NOMMU
	bool

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config CPU_ABRT_EV4
	bool

config CPU_ABRT_EV4T
	bool

config CPU_ABRT_LV4T
	bool

config CPU_ABRT_EV5T
	bool

config CPU_ABRT_EV5TJ
	bool

config CPU_ABRT_EV6
	bool

# The cache model
config CPU_CACHE_V3
	bool

config CPU_CACHE_V4
	bool

config CPU_CACHE_V4WT
	bool

config CPU_CACHE_V4WB
	bool

config CPU_CACHE_V6
	bool

config CPU_CACHE_VIVT
	bool

config CPU_CACHE_VIPT
	bool

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if MMU
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# The copy-page model
config CPU_COPY_V3
	bool

config CPU_COPY_V4WT
	bool

config CPU_COPY_V4WB
	bool

config CPU_COPY_V6
	bool

# This selects the TLB model
config CPU_TLB_V3
	bool
	help
	  ARM Architecture Version 3 TLB.

config CPU_TLB_V4WT
	bool
	help
	  ARM Architecture Version 4 TLB with writethrough cache.

config CPU_TLB_V4WB
	bool
	help
	  ARM Architecture Version 4 TLB with writeback cache.

config CPU_TLB_V4WBI
	bool
	help
	  ARM Architecture Version 4 TLB with writeback cache and invalidate
	  instruction cache entry.

config CPU_TLB_V6
	bool

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endif

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config CPU_CP15
	bool
	help
	  Processor has the CP15 register.

config CPU_CP15_MMU
	bool
	select CPU_CP15
	help
	  Processor has the CP15 register, which has MMU related registers.

config CPU_CP15_MPU
	bool
	select CPU_CP15
	help
	  Processor has the CP15 register, which has MPU related registers.

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#
# CPU supports 36-bit I/O
#
config IO_36
	bool

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comment "Processor Features"

config ARM_THUMB
	bool "Support Thumb user binaries"
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	depends on CPU_ARM720T || CPU_ARM740T || CPU_ARM920T || CPU_ARM922T || CPU_ARM925T || CPU_ARM926T || CPU_ARM940T || CPU_ARM946E || CPU_ARM1020 || CPU_ARM1020E || CPU_ARM1022 || CPU_ARM1026 || CPU_XSCALE || CPU_XSC3 || CPU_V6
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	default y
	help
	  Say Y if you want to include kernel support for running user space
	  Thumb binaries.

	  The Thumb instruction set is a compressed form of the standard ARM
	  instruction set resulting in smaller binaries at the expense of
	  slightly less efficient code.

	  If you don't know what this all is, saying Y is a safe choice.

config CPU_BIG_ENDIAN
	bool "Build big-endian kernel"
	depends on ARCH_SUPPORTS_BIG_ENDIAN
	help
	  Say Y if you plan on running a kernel in big-endian mode.
	  Note that your board must be properly built and your board
	  port must properly enable any big-endian related features
	  of your chipset/board/processor.

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config CPU_HIGH_VECTOR
	depends !MMU && CPU_CP15 && !CPU_ARM740T
	bool "Select the High exception vector"
	default n
	help
	  Say Y here to select high exception vector(0xFFFF0000~).
	  The exception vector can be vary depending on the platform
	  design in nommu mode. If your platform needs to select
	  high exception vector, say Y.
	  Otherwise or if you are unsure, say N, and the low exception
	  vector (0x00000000~) will be used.

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config CPU_ICACHE_DISABLE
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	bool "Disable I-Cache (I-bit)"
	depends on CPU_CP15 && !(CPU_ARM610 || CPU_ARM710 || CPU_ARM720T || CPU_ARM740T || CPU_XSCALE || CPU_XSC3)
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	help
	  Say Y here to disable the processor instruction cache. Unless
	  you have a reason not to or are unsure, say N.

config CPU_DCACHE_DISABLE
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	bool "Disable D-Cache (C-bit)"
	depends on CPU_CP15
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	help
	  Say Y here to disable the processor data cache. Unless
	  you have a reason not to or are unsure, say N.

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config CPU_DCACHE_SIZE
	hex
	depends on CPU_ARM740T || CPU_ARM946E
	default 0x00001000 if CPU_ARM740T
	default 0x00002000 # default size for ARM946E-S
	help
	  Some cores are synthesizable to have various sized cache. For
	  ARM946E-S case, it can vary from 0KB to 1MB.
	  To support such cache operations, it is efficient to know the size
	  before compile time.
	  If your SoC is configured to have a different size, define the value
	  here with proper conditions.

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config CPU_DCACHE_WRITETHROUGH
	bool "Force write through D-cache"
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	depends on (CPU_ARM740T || CPU_ARM920T || CPU_ARM922T || CPU_ARM925T || CPU_ARM926T || CPU_ARM940T || CPU_ARM946E || CPU_ARM1020 || CPU_V6) && !CPU_DCACHE_DISABLE
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	default y if CPU_ARM925T
	help
	  Say Y here to use the data cache in writethrough mode. Unless you
	  specifically require this or are unsure, say N.

config CPU_CACHE_ROUND_ROBIN
	bool "Round robin I and D cache replacement algorithm"
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	depends on (CPU_ARM926T || CPU_ARM946E || CPU_ARM1020) && (!CPU_ICACHE_DISABLE || !CPU_DCACHE_DISABLE)
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	help
	  Say Y here to use the predictable round-robin cache replacement
	  policy.  Unless you specifically require this or are unsure, say N.

config CPU_BPREDICT_DISABLE
	bool "Disable branch prediction"
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	depends on CPU_ARM1020 || CPU_V6 || CPU_XSC3
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	help
	  Say Y here to disable branch prediction.  If unsure, say N.
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config TLS_REG_EMUL
	bool
	help
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	  An SMP system using a pre-ARMv6 processor (there are apparently
	  a few prototypes like that in existence) and therefore access to
	  that required register must be emulated.
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config HAS_TLS_REG
	bool
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	depends on !TLS_REG_EMUL
	default y if SMP || CPU_32v7
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	help
	  This selects support for the CP15 thread register.
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	  It is defined to be available on some ARMv6 processors (including
	  all SMP capable ARMv6's) or later processors.  User space may
	  assume directly accessing that register and always obtain the
	  expected value only on ARMv7 and above.
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config NEEDS_SYSCALL_FOR_CMPXCHG
	bool
	help
	  SMP on a pre-ARMv6 processor?  Well OK then.
	  Forget about fast user space cmpxchg support.
	  It is just not possible.