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+# SPDX-License-Identifier: GPL-2.0
+comment "Processor Type"
+
+# Select CPU types depending on the architecture selected. This selects
+# which CPUs we support in the kernel image, and the compiler instruction
+# optimiser behaviour.
+
+# ARM7TDMI
+config CPU_ARM7TDMI
+ bool
+ depends on !MMU
+ select CPU_32v4T
+ select CPU_ABRT_LV4T
+ select CPU_CACHE_V4
+ select CPU_PABRT_LEGACY
+ 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.
+
+# ARM720T
+config CPU_ARM720T
+ bool
+ select CPU_32v4T
+ select CPU_ABRT_LV4T
+ select CPU_CACHE_V4
+ select CPU_CACHE_VIVT
+ select CPU_COPY_V4WT if MMU
+ select CPU_CP15_MMU
+ select CPU_PABRT_LEGACY
+ select CPU_THUMB_CAPABLE
+ select CPU_TLB_V4WT if MMU
+ 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.
+
+# ARM740T
+config CPU_ARM740T
+ bool
+ depends on !MMU
+ select CPU_32v4T
+ select CPU_ABRT_LV4T
+ select CPU_CACHE_V4
+ select CPU_CP15_MPU
+ select CPU_PABRT_LEGACY
+ select CPU_THUMB_CAPABLE
+ 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.
+
+# ARM9TDMI
+config CPU_ARM9TDMI
+ bool
+ depends on !MMU
+ select CPU_32v4T
+ select CPU_ABRT_NOMMU
+ select CPU_CACHE_V4
+ select CPU_PABRT_LEGACY
+ 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.
+
+# ARM920T
+config CPU_ARM920T
+ bool
+ select CPU_32v4T
+ select CPU_ABRT_EV4T
+ select CPU_CACHE_V4WT
+ select CPU_CACHE_VIVT
+ select CPU_COPY_V4WB if MMU
+ select CPU_CP15_MMU
+ select CPU_PABRT_LEGACY
+ select CPU_THUMB_CAPABLE
+ select CPU_TLB_V4WBI if MMU
+ help
+ The ARM920T is licensed to be produced by numerous vendors,
+ and is used in the Cirrus EP93xx and the Samsung S3C2410.
+
+ Say Y if you want support for the ARM920T processor.
+ Otherwise, say N.
+
+# ARM922T
+config CPU_ARM922T
+ bool
+ select CPU_32v4T
+ select CPU_ABRT_EV4T
+ select CPU_CACHE_V4WT
+ select CPU_CACHE_VIVT
+ select CPU_COPY_V4WB if MMU
+ select CPU_CP15_MMU
+ select CPU_PABRT_LEGACY
+ select CPU_THUMB_CAPABLE
+ select CPU_TLB_V4WBI if MMU
+ 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 and the ARM Integrator.
+
+ Say Y if you want support for the ARM922T processor.
+ Otherwise, say N.
+
+# ARM925T
+config CPU_ARM925T
+ bool
+ select CPU_32v4T
+ select CPU_ABRT_EV4T
+ select CPU_CACHE_V4WT
+ select CPU_CACHE_VIVT
+ select CPU_COPY_V4WB if MMU
+ select CPU_CP15_MMU
+ select CPU_PABRT_LEGACY
+ select CPU_THUMB_CAPABLE
+ select CPU_TLB_V4WBI if MMU
+ 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
+ bool
+ select CPU_32v5
+ select CPU_ABRT_EV5TJ
+ select CPU_CACHE_VIVT
+ select CPU_COPY_V4WB if MMU
+ select CPU_CP15_MMU
+ select CPU_PABRT_LEGACY
+ select CPU_THUMB_CAPABLE
+ select CPU_TLB_V4WBI if MMU
+ 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.
+
+# FA526
+config CPU_FA526
+ bool
+ select CPU_32v4
+ select CPU_ABRT_EV4
+ select CPU_CACHE_FA
+ select CPU_CACHE_VIVT
+ select CPU_COPY_FA if MMU
+ select CPU_CP15_MMU
+ select CPU_PABRT_LEGACY
+ select CPU_TLB_FA if MMU
+ help
+ The FA526 is a version of the ARMv4 compatible processor with
+ Branch Target Buffer, Unified TLB and cache line size 16.
+
+ Say Y if you want support for the FA526 processor.
+ Otherwise, say N.
+
+# ARM940T
+config CPU_ARM940T
+ bool
+ depends on !MMU
+ select CPU_32v4T
+ select CPU_ABRT_NOMMU
+ select CPU_CACHE_VIVT
+ select CPU_CP15_MPU
+ select CPU_PABRT_LEGACY
+ select CPU_THUMB_CAPABLE
+ help
+ ARM940T is a member of the ARM9TDMI family of general-
+ purpose microprocessors with MPU and separate 4KB
+ 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.
+
+# ARM946E-S
+config CPU_ARM946E
+ bool
+ depends on !MMU
+ select CPU_32v5
+ select CPU_ABRT_NOMMU
+ select CPU_CACHE_VIVT
+ select CPU_CP15_MPU
+ select CPU_PABRT_LEGACY
+ select CPU_THUMB_CAPABLE
+ 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.
+
+# ARM1020 - needs validating
+config CPU_ARM1020
+ bool
+ select CPU_32v5
+ select CPU_ABRT_EV4T
+ select CPU_CACHE_V4WT
+ select CPU_CACHE_VIVT
+ select CPU_COPY_V4WB if MMU
+ select CPU_CP15_MMU
+ select CPU_PABRT_LEGACY
+ select CPU_THUMB_CAPABLE
+ select CPU_TLB_V4WBI if MMU
+ 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
+ depends on n
+ select CPU_32v5
+ select CPU_ABRT_EV4T
+ select CPU_CACHE_V4WT
+ select CPU_CACHE_VIVT
+ select CPU_COPY_V4WB if MMU
+ select CPU_CP15_MMU
+ select CPU_PABRT_LEGACY
+ select CPU_THUMB_CAPABLE
+ select CPU_TLB_V4WBI if MMU
+
+# ARM1022E
+config CPU_ARM1022
+ bool
+ select CPU_32v5
+ select CPU_ABRT_EV4T
+ select CPU_CACHE_VIVT
+ select CPU_COPY_V4WB if MMU # can probably do better
+ select CPU_CP15_MMU
+ select CPU_PABRT_LEGACY
+ select CPU_THUMB_CAPABLE
+ select CPU_TLB_V4WBI if MMU
+ 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
+ select CPU_32v5
+ select CPU_ABRT_EV5T # But need Jazelle, but EV5TJ ignores bit 10
+ select CPU_CACHE_VIVT
+ select CPU_COPY_V4WB if MMU # can probably do better
+ select CPU_CP15_MMU
+ select CPU_PABRT_LEGACY
+ select CPU_THUMB_CAPABLE
+ select CPU_TLB_V4WBI if MMU
+ 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
+ select CPU_32v3 if ARCH_RPC
+ select CPU_32v4 if !ARCH_RPC
+ select CPU_ABRT_EV4
+ select CPU_CACHE_V4WB
+ select CPU_CACHE_VIVT
+ select CPU_COPY_V4WB if MMU
+ select CPU_CP15_MMU
+ select CPU_PABRT_LEGACY
+ select CPU_TLB_V4WB if MMU
+ 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
+ select CPU_32v4
+ select CPU_ABRT_EV4
+ select CPU_CACHE_V4WB
+ select CPU_CACHE_VIVT
+ select CPU_CP15_MMU
+ select CPU_PABRT_LEGACY
+ select CPU_TLB_V4WB if MMU
+
+# XScale
+config CPU_XSCALE
+ bool
+ select CPU_32v5
+ select CPU_ABRT_EV5T
+ select CPU_CACHE_VIVT
+ select CPU_CP15_MMU
+ select CPU_PABRT_LEGACY
+ select CPU_THUMB_CAPABLE
+ select CPU_TLB_V4WBI if MMU
+
+# XScale Core Version 3
+config CPU_XSC3
+ bool
+ select CPU_32v5
+ select CPU_ABRT_EV5T
+ select CPU_CACHE_VIVT
+ select CPU_CP15_MMU
+ select CPU_PABRT_LEGACY
+ select CPU_THUMB_CAPABLE
+ select CPU_TLB_V4WBI if MMU
+ select IO_36
+
+# Marvell PJ1 (Mohawk)
+config CPU_MOHAWK
+ bool
+ select CPU_32v5
+ select CPU_ABRT_EV5T
+ select CPU_CACHE_VIVT
+ select CPU_COPY_V4WB if MMU
+ select CPU_CP15_MMU
+ select CPU_PABRT_LEGACY
+ select CPU_THUMB_CAPABLE
+ select CPU_TLB_V4WBI if MMU
+
+# Feroceon
+config CPU_FEROCEON
+ bool
+ select CPU_32v5
+ select CPU_ABRT_EV5T
+ select CPU_CACHE_VIVT
+ select CPU_COPY_FEROCEON if MMU
+ select CPU_CP15_MMU
+ select CPU_PABRT_LEGACY
+ select CPU_THUMB_CAPABLE
+ select CPU_TLB_FEROCEON if MMU
+
+config CPU_FEROCEON_OLD_ID
+ bool "Accept early Feroceon cores with an ARM926 ID"
+ depends on CPU_FEROCEON && !CPU_ARM926T
+ default y
+ help
+ This enables the usage of some old Feroceon cores
+ for which the CPU ID is equal to the ARM926 ID.
+ Relevant for Feroceon-1850 and early Feroceon-2850.
+
+# Marvell PJ4
+config CPU_PJ4
+ bool
+ select ARM_THUMBEE
+ select CPU_V7
+
+config CPU_PJ4B
+ bool
+ select CPU_V7
+
+# ARMv6
+config CPU_V6
+ bool
+ select CPU_32v6
+ select CPU_ABRT_EV6
+ select CPU_CACHE_V6
+ select CPU_CACHE_VIPT
+ select CPU_COPY_V6 if MMU
+ select CPU_CP15_MMU
+ select CPU_HAS_ASID if MMU
+ select CPU_PABRT_V6
+ select CPU_THUMB_CAPABLE
+ select CPU_TLB_V6 if MMU
+ select SMP_ON_UP if SMP
+
+# ARMv6k
+config CPU_V6K
+ bool
+ select CPU_32v6
+ select CPU_32v6K
+ select CPU_ABRT_EV6
+ select CPU_CACHE_V6
+ select CPU_CACHE_VIPT
+ select CPU_COPY_V6 if MMU
+ select CPU_CP15_MMU
+ select CPU_HAS_ASID if MMU
+ select CPU_PABRT_V6
+ select CPU_THUMB_CAPABLE
+ select CPU_TLB_V6 if MMU
+
+# ARMv7
+config CPU_V7
+ bool
+ select CPU_32v6K
+ select CPU_32v7
+ select CPU_ABRT_EV7
+ select CPU_CACHE_V7
+ select CPU_CACHE_VIPT
+ select CPU_COPY_V6 if MMU
+ select CPU_CP15_MMU if MMU
+ select CPU_CP15_MPU if !MMU
+ select CPU_HAS_ASID if MMU
+ select CPU_PABRT_V7
+ select CPU_SPECTRE if MMU
+ select CPU_THUMB_CAPABLE
+ select CPU_TLB_V7 if MMU
+
+# ARMv7M
+config CPU_V7M
+ bool
+ select CPU_32v7M
+ select CPU_ABRT_NOMMU
+ select CPU_CACHE_V7M
+ select CPU_CACHE_NOP
+ select CPU_PABRT_LEGACY
+ select CPU_THUMBONLY
+
+config CPU_THUMBONLY
+ bool
+ select CPU_THUMB_CAPABLE
+ # There are no CPUs available with MMU that don't implement an ARM ISA:
+ depends on !MMU
+ help
+ Select this if your CPU doesn't support the 32 bit ARM instructions.
+
+config CPU_THUMB_CAPABLE
+ bool
+ help
+ Select this if your CPU can support Thumb mode.
+
+# 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
+ select CPU_USE_DOMAINS if MMU
+ select NEED_KUSER_HELPERS
+ select TLS_REG_EMUL if SMP || !MMU
+ select CPU_NO_EFFICIENT_FFS
+
+config CPU_32v4
+ bool
+ select CPU_USE_DOMAINS if MMU
+ select NEED_KUSER_HELPERS
+ select TLS_REG_EMUL if SMP || !MMU
+ select CPU_NO_EFFICIENT_FFS
+
+config CPU_32v4T
+ bool
+ select CPU_USE_DOMAINS if MMU
+ select NEED_KUSER_HELPERS
+ select TLS_REG_EMUL if SMP || !MMU
+ select CPU_NO_EFFICIENT_FFS
+
+config CPU_32v5
+ bool
+ select CPU_USE_DOMAINS if MMU
+ select NEED_KUSER_HELPERS
+ select TLS_REG_EMUL if SMP || !MMU
+
+config CPU_32v6
+ bool
+ select TLS_REG_EMUL if !CPU_32v6K && !MMU
+
+config CPU_32v6K
+ bool
+
+config CPU_32v7
+ bool
+
+config CPU_32v7M
+ bool
+
+# The abort model
+config CPU_ABRT_NOMMU
+ bool
+
+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
+
+config CPU_ABRT_EV7
+ bool
+
+config CPU_PABRT_LEGACY
+ bool
+
+config CPU_PABRT_V6
+ bool
+
+config CPU_PABRT_V7
+ bool
+
+# The cache model
+config CPU_CACHE_V4
+ bool
+
+config CPU_CACHE_V4WT
+ bool
+
+config CPU_CACHE_V4WB
+ bool
+
+config CPU_CACHE_V6
+ bool
+
+config CPU_CACHE_V7
+ bool
+
+config CPU_CACHE_NOP
+ bool
+
+config CPU_CACHE_VIVT
+ bool
+
+config CPU_CACHE_VIPT
+ bool
+
+config CPU_CACHE_FA
+ bool
+
+config CPU_CACHE_V7M
+ bool
+
+if MMU
+# The copy-page model
+config CPU_COPY_V4WT
+ bool
+
+config CPU_COPY_V4WB
+ bool
+
+config CPU_COPY_FEROCEON
+ bool
+
+config CPU_COPY_FA
+ bool
+
+config CPU_COPY_V6
+ bool
+
+# This selects the TLB model
+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_FEROCEON
+ bool
+ help
+ Feroceon TLB (v4wbi with non-outer-cachable page table walks).
+
+config CPU_TLB_FA
+ bool
+ help
+ Faraday ARM FA526 architecture, unified TLB with writeback cache
+ and invalidate instruction cache entry. Branch target buffer is
+ also supported.
+
+config CPU_TLB_V6
+ bool
+
+config CPU_TLB_V7
+ bool
+
+endif
+
+config CPU_HAS_ASID
+ bool
+ help
+ This indicates whether the CPU has the ASID register; used to
+ tag TLB and possibly cache entries.
+
+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.
+
+config CPU_USE_DOMAINS
+ bool
+ help
+ This option enables or disables the use of domain switching
+ using the DACR (domain access control register) to protect memory
+ domains from each other. In Linux we use three domains: kernel, user
+ and IO. The domains are used to protect userspace from kernelspace
+ and to handle IO-space as a special type of memory by assigning
+ manager or client roles to running code (such as a process).
+
+config CPU_V7M_NUM_IRQ
+ int "Number of external interrupts connected to the NVIC"
+ depends on CPU_V7M
+ default 90 if ARCH_STM32
+ default 112 if SOC_VF610
+ default 240
+ help
+ This option indicates the number of interrupts connected to the NVIC.
+ The value can be larger than the real number of interrupts supported
+ by the system, but must not be lower.
+ The default value is 240, corresponding to the maximum number of
+ interrupts supported by the NVIC on Cortex-M family.
+
+ If unsure, keep default value.
+
+#
+# CPU supports 36-bit I/O
+#
+config IO_36
+ bool
+
+comment "Processor Features"
+
+config ARM_LPAE
+ bool "Support for the Large Physical Address Extension"
+ depends on MMU && CPU_32v7 && !CPU_32v6 && !CPU_32v5 && \
+ !CPU_32v4 && !CPU_32v3
+ select PHYS_ADDR_T_64BIT
+ select SWIOTLB
+ help
+ Say Y if you have an ARMv7 processor supporting the LPAE page
+ table format and you would like to access memory beyond the
+ 4GB limit. The resulting kernel image will not run on
+ processors without the LPA extension.
+
+ If unsure, say N.
+
+config ARM_PV_FIXUP
+ def_bool y
+ depends on ARM_LPAE && ARM_PATCH_PHYS_VIRT && ARCH_KEYSTONE
+
+config ARM_THUMB
+ bool "Support Thumb user binaries" if !CPU_THUMBONLY && EXPERT
+ depends on CPU_THUMB_CAPABLE && !CPU_32v4
+ 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 this option is disabled, and you run userspace that switches to
+ Thumb mode, signal handling will not work correctly, resulting in
+ segmentation faults or illegal instruction aborts.
+
+ If you don't know what this all is, saying Y is a safe choice.
+
+config ARM_THUMBEE
+ bool "Enable ThumbEE CPU extension"
+ depends on CPU_V7
+ help
+ Say Y here if you have a CPU with the ThumbEE extension and code to
+ make use of it. Say N for code that can run on CPUs without ThumbEE.
+
+config ARM_VIRT_EXT
+ bool
+ default y if CPU_V7
+ help
+ Enable the kernel to make use of the ARM Virtualization
+ Extensions to install hypervisors without run-time firmware
+ assistance.
+
+ A compliant bootloader is required in order to make maximum
+ use of this feature. Refer to Documentation/arm/booting.rst for
+ details.
+
+config SWP_EMULATE
+ bool "Emulate SWP/SWPB instructions" if !SMP
+ depends on CPU_V7
+ default y if SMP
+ select HAVE_PROC_CPU if PROC_FS
+ help
+ ARMv6 architecture deprecates use of the SWP/SWPB instructions.
+ ARMv7 multiprocessing extensions introduce the ability to disable
+ these instructions, triggering an undefined instruction exception
+ when executed. Say Y here to enable software emulation of these
+ instructions for userspace (not kernel) using LDREX/STREX.
+ Also creates /proc/cpu/swp_emulation for statistics.
+
+ In some older versions of glibc [<=2.8] SWP is used during futex
+ trylock() operations with the assumption that the code will not
+ be preempted. This invalid assumption may be more likely to fail
+ with SWP emulation enabled, leading to deadlock of the user
+ application.
+
+ NOTE: when accessing uncached shared regions, LDREX/STREX rely
+ on an external transaction monitoring block called a global
+ monitor to maintain update atomicity. If your system does not
+ implement a global monitor, this option can cause programs that
+ perform SWP operations to uncached memory to deadlock.
+
+ If unsure, say Y.
+
+choice
+ prompt "CPU Endianess"
+ default CPU_LITTLE_ENDIAN
+
+config CPU_LITTLE_ENDIAN
+ bool "Built little-endian kernel"
+ help
+ Say Y if you plan on running a kernel in little-endian mode.
+ This is the default and is used in practically all modern user
+ space builds.
+
+config CPU_BIG_ENDIAN
+ bool "Build big-endian kernel"
+ depends on !LD_IS_LLD
+ help
+ Say Y if you plan on running a kernel in big-endian mode.
+ This works on many machines using ARMv6 or newer processors
+ but requires big-endian user space.
+
+ The only ARMv5 platform with big-endian support is
+ Intel IXP4xx.
+
+endchoice
+
+config CPU_ENDIAN_BE8
+ bool
+ depends on CPU_BIG_ENDIAN
+ default CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7M
+ help
+ Support for the BE-8 (big-endian) mode on ARMv6 and ARMv7 processors.
+
+config CPU_ENDIAN_BE32
+ bool
+ depends on CPU_BIG_ENDIAN
+ default !CPU_ENDIAN_BE8
+ help
+ Support for the BE-32 (big-endian) mode on pre-ARMv6 processors.
+
+config CPU_HIGH_VECTOR
+ depends on !MMU && CPU_CP15 && !CPU_ARM740T
+ bool "Select the High exception vector"
+ help
+ Say Y here to select high exception vector(0xFFFF0000~).
+ The exception vector can 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.
+
+config CPU_ICACHE_DISABLE
+ bool "Disable I-Cache (I-bit)"
+ depends on (CPU_CP15 && !(CPU_ARM720T || CPU_ARM740T || CPU_XSCALE || CPU_XSC3)) || CPU_V7M
+ help
+ Say Y here to disable the processor instruction cache. Unless
+ you have a reason not to or are unsure, say N.
+
+config CPU_ICACHE_MISMATCH_WORKAROUND
+ bool "Workaround for I-Cache line size mismatch between CPU cores"
+ depends on SMP && CPU_V7
+ help
+ Some big.LITTLE systems have I-Cache line size mismatch between
+ LITTLE and big cores. Say Y here to enable a workaround for
+ proper I-Cache support on such systems. If unsure, say N.
+
+config CPU_DCACHE_DISABLE
+ bool "Disable D-Cache (C-bit)"
+ depends on (CPU_CP15 && !SMP) || CPU_V7M
+ help
+ Say Y here to disable the processor data cache. Unless
+ you have a reason not to or are unsure, say N.
+
+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.
+
+config CPU_DCACHE_WRITETHROUGH
+ bool "Force write through D-cache"
+ depends on (CPU_ARM740T || CPU_ARM920T || CPU_ARM922T || CPU_ARM925T || CPU_ARM926T || CPU_ARM940T || CPU_ARM946E || CPU_ARM1020 || CPU_FA526) && !CPU_DCACHE_DISABLE
+ 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"
+ depends on (CPU_ARM926T || CPU_ARM946E || CPU_ARM1020) && (!CPU_ICACHE_DISABLE || !CPU_DCACHE_DISABLE)
+ 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"
+ depends on CPU_ARM1020 || CPU_V6 || CPU_V6K || CPU_MOHAWK || CPU_XSC3 || CPU_V7 || CPU_FA526 || CPU_V7M
+ help
+ Say Y here to disable branch prediction. If unsure, say N.
+
+config CPU_SPECTRE
+ bool
+ select GENERIC_CPU_VULNERABILITIES
+
+config HARDEN_BRANCH_PREDICTOR
+ bool "Harden the branch predictor against aliasing attacks" if EXPERT
+ depends on CPU_SPECTRE
+ default y
+ help
+ Speculation attacks against some high-performance processors rely
+ on being able to manipulate the branch predictor for a victim
+ context by executing aliasing branches in the attacker context.
+ Such attacks can be partially mitigated against by clearing
+ internal branch predictor state and limiting the prediction
+ logic in some situations.
+
+ This config option will take CPU-specific actions to harden
+ the branch predictor against aliasing attacks and may rely on
+ specific instruction sequences or control bits being set by
+ the system firmware.
+
+ If unsure, say Y.
+
+config HARDEN_BRANCH_HISTORY
+ bool "Harden Spectre style attacks against branch history" if EXPERT
+ depends on CPU_SPECTRE
+ default y
+ help
+ Speculation attacks against some high-performance processors can
+ make use of branch history to influence future speculation. When
+ taking an exception, a sequence of branches overwrites the branch
+ history, or branch history is invalidated.
+
+config TLS_REG_EMUL
+ bool
+ select NEED_KUSER_HELPERS
+ help
+ 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.
+
+config NEED_KUSER_HELPERS
+ bool
+
+config KUSER_HELPERS
+ bool "Enable kuser helpers in vector page" if !NEED_KUSER_HELPERS
+ depends on MMU
+ default y
+ help
+ Warning: disabling this option may break user programs.
+
+ Provide kuser helpers in the vector page. The kernel provides
+ helper code to userspace in read only form at a fixed location
+ in the high vector page to allow userspace to be independent of
+ the CPU type fitted to the system. This permits binaries to be
+ run on ARMv4 through to ARMv7 without modification.
+
+ See Documentation/arm/kernel_user_helpers.rst for details.
+
+ However, the fixed address nature of these helpers can be used
+ by ROP (return orientated programming) authors when creating
+ exploits.
+
+ If all of the binaries and libraries which run on your platform
+ are built specifically for your platform, and make no use of
+ these helpers, then you can turn this option off to hinder
+ such exploits. However, in that case, if a binary or library
+ relying on those helpers is run, it will receive a SIGILL signal,
+ which will terminate the program.
+
+ Say N here only if you are absolutely certain that you do not
+ need these helpers; otherwise, the safe option is to say Y.
+
+config VDSO
+ bool "Enable VDSO for acceleration of some system calls"
+ depends on AEABI && MMU && CPU_V7
+ default y if ARM_ARCH_TIMER
+ select HAVE_GENERIC_VDSO
+ select GENERIC_TIME_VSYSCALL
+ select GENERIC_VDSO_32
+ select GENERIC_GETTIMEOFDAY
+ help
+ Place in the process address space an ELF shared object
+ providing fast implementations of gettimeofday and
+ clock_gettime. Systems that implement the ARM architected
+ timer will receive maximum benefit.
+
+ You must have glibc 2.22 or later for programs to seamlessly
+ take advantage of this.
+
+config DMA_CACHE_RWFO
+ bool "Enable read/write for ownership DMA cache maintenance"
+ depends on CPU_V6K && SMP
+ default y
+ help
+ The Snoop Control Unit on ARM11MPCore does not detect the
+ cache maintenance operations and the dma_{map,unmap}_area()
+ functions may leave stale cache entries on other CPUs. By
+ enabling this option, Read or Write For Ownership in the ARMv6
+ DMA cache maintenance functions is performed. These LDR/STR
+ instructions change the cache line state to shared or modified
+ so that the cache operation has the desired effect.
+
+ Note that the workaround is only valid on processors that do
+ not perform speculative loads into the D-cache. For such
+ processors, if cache maintenance operations are not broadcast
+ in hardware, other workarounds are needed (e.g. cache
+ maintenance broadcasting in software via FIQ).
+
+config OUTER_CACHE
+ bool
+
+config OUTER_CACHE_SYNC
+ bool
+ select ARM_HEAVY_MB
+ help
+ The outer cache has a outer_cache_fns.sync function pointer
+ that can be used to drain the write buffer of the outer cache.
+
+config CACHE_B15_RAC
+ bool "Enable the Broadcom Brahma-B15 read-ahead cache controller"
+ depends on ARCH_BRCMSTB
+ default y
+ help
+ This option enables the Broadcom Brahma-B15 read-ahead cache
+ controller. If disabled, the read-ahead cache remains off.
+
+config CACHE_FEROCEON_L2
+ bool "Enable the Feroceon L2 cache controller"
+ depends on ARCH_MV78XX0 || ARCH_MVEBU
+ default y
+ select OUTER_CACHE
+ help
+ This option enables the Feroceon L2 cache controller.
+
+config CACHE_FEROCEON_L2_WRITETHROUGH
+ bool "Force Feroceon L2 cache write through"
+ depends on CACHE_FEROCEON_L2
+ help
+ Say Y here to use the Feroceon L2 cache in writethrough mode.
+ Unless you specifically require this, say N for writeback mode.
+
+config MIGHT_HAVE_CACHE_L2X0
+ bool
+ help
+ This option should be selected by machines which have a L2x0
+ or PL310 cache controller, but where its use is optional.
+
+ The only effect of this option is to make CACHE_L2X0 and
+ related options available to the user for configuration.
+
+ Boards or SoCs which always require the cache controller
+ support to be present should select CACHE_L2X0 directly
+ instead of this option, thus preventing the user from
+ inadvertently configuring a broken kernel.
+
+config CACHE_L2X0
+ bool "Enable the L2x0 outer cache controller" if MIGHT_HAVE_CACHE_L2X0
+ default MIGHT_HAVE_CACHE_L2X0
+ select OUTER_CACHE
+ select OUTER_CACHE_SYNC
+ help
+ This option enables the L2x0 PrimeCell.
+
+config CACHE_L2X0_PMU
+ bool "L2x0 performance monitor support" if CACHE_L2X0
+ depends on PERF_EVENTS
+ help
+ This option enables support for the performance monitoring features
+ of the L220 and PL310 outer cache controllers.
+
+if CACHE_L2X0
+
+config PL310_ERRATA_588369
+ bool "PL310 errata: Clean & Invalidate maintenance operations do not invalidate clean lines"
+ help
+ The PL310 L2 cache controller implements three types of Clean &
+ Invalidate maintenance operations: by Physical Address
+ (offset 0x7F0), by Index/Way (0x7F8) and by Way (0x7FC).
+ They are architecturally defined to behave as the execution of a
+ clean operation followed immediately by an invalidate operation,
+ both performing to the same memory location. This functionality
+ is not correctly implemented in PL310 prior to r2p0 (fixed in r2p0)
+ as clean lines are not invalidated as a result of these operations.
+
+config PL310_ERRATA_727915
+ bool "PL310 errata: Background Clean & Invalidate by Way operation can cause data corruption"
+ help
+ PL310 implements the Clean & Invalidate by Way L2 cache maintenance
+ operation (offset 0x7FC). This operation runs in background so that
+ PL310 can handle normal accesses while it is in progress. Under very
+ rare circumstances, due to this erratum, write data can be lost when
+ PL310 treats a cacheable write transaction during a Clean &
+ Invalidate by Way operation. Revisions prior to r3p1 are affected by
+ this errata (fixed in r3p1).
+
+config PL310_ERRATA_753970
+ bool "PL310 errata: cache sync operation may be faulty"
+ help
+ This option enables the workaround for the 753970 PL310 (r3p0) erratum.
+
+ Under some condition the effect of cache sync operation on
+ the store buffer still remains when the operation completes.
+ This means that the store buffer is always asked to drain and
+ this prevents it from merging any further writes. The workaround
+ is to replace the normal offset of cache sync operation (0x730)
+ by another offset targeting an unmapped PL310 register 0x740.
+ This has the same effect as the cache sync operation: store buffer
+ drain and waiting for all buffers empty.
+
+config PL310_ERRATA_769419
+ bool "PL310 errata: no automatic Store Buffer drain"
+ help
+ On revisions of the PL310 prior to r3p2, the Store Buffer does
+ not automatically drain. This can cause normal, non-cacheable
+ writes to be retained when the memory system is idle, leading
+ to suboptimal I/O performance for drivers using coherent DMA.
+ This option adds a write barrier to the cpu_idle loop so that,
+ on systems with an outer cache, the store buffer is drained
+ explicitly.
+
+endif
+
+config CACHE_TAUROS2
+ bool "Enable the Tauros2 L2 cache controller"
+ depends on (CPU_MOHAWK || CPU_PJ4)
+ default y
+ select OUTER_CACHE
+ help
+ This option enables the Tauros2 L2 cache controller (as
+ found on PJ1/PJ4).
+
+config CACHE_UNIPHIER
+ bool "Enable the UniPhier outer cache controller"
+ depends on ARCH_UNIPHIER
+ select ARM_L1_CACHE_SHIFT_7
+ select OUTER_CACHE
+ select OUTER_CACHE_SYNC
+ help
+ This option enables the UniPhier outer cache (system cache)
+ controller.
+
+config CACHE_XSC3L2
+ bool "Enable the L2 cache on XScale3"
+ depends on CPU_XSC3
+ default y
+ select OUTER_CACHE
+ help
+ This option enables the L2 cache on XScale3.
+
+config ARM_L1_CACHE_SHIFT_6
+ bool
+ default y if CPU_V7
+ help
+ Setting ARM L1 cache line size to 64 Bytes.
+
+config ARM_L1_CACHE_SHIFT_7
+ bool
+ help
+ Setting ARM L1 cache line size to 128 Bytes.
+
+config ARM_L1_CACHE_SHIFT
+ int
+ default 7 if ARM_L1_CACHE_SHIFT_7
+ default 6 if ARM_L1_CACHE_SHIFT_6
+ default 5
+
+config ARM_DMA_MEM_BUFFERABLE
+ bool "Use non-cacheable memory for DMA" if (CPU_V6 || CPU_V6K || CPU_V7M) && !CPU_V7
+ default y if CPU_V6 || CPU_V6K || CPU_V7 || CPU_V7M
+ help
+ Historically, the kernel has used strongly ordered mappings to
+ provide DMA coherent memory. With the advent of ARMv7, mapping
+ memory with differing types results in unpredictable behaviour,
+ so on these CPUs, this option is forced on.
+
+ Multiple mappings with differing attributes is also unpredictable
+ on ARMv6 CPUs, but since they do not have aggressive speculative
+ prefetch, no harm appears to occur.
+
+ However, drivers may be missing the necessary barriers for ARMv6,
+ and therefore turning this on may result in unpredictable driver
+ behaviour. Therefore, we offer this as an option.
+
+ On some of the beefier ARMv7-M machines (with DMA and write
+ buffers) you likely want this enabled, while those that
+ didn't need it until now also won't need it in the future.
+
+ You are recommended say 'Y' here and debug any affected drivers.
+
+config ARM_HEAVY_MB
+ bool
+
+config DEBUG_ALIGN_RODATA
+ bool "Make rodata strictly non-executable"
+ depends on STRICT_KERNEL_RWX
+ default y
+ help
+ If this is set, rodata will be made explicitly non-executable. This
+ provides protection on the rare chance that attackers might find and
+ use ROP gadgets that exist in the rodata section. This adds an
+ additional section-aligned split of rodata from kernel text so it
+ can be made explicitly non-executable. This padding may waste memory
+ space to gain the additional protection.