zephyr/arch/Kconfig

# Kconfig - general architecture configuration options

#
# Copyright (c) 2014-2015 Wind River Systems, Inc.
# Copyright (c) 2015 Intel Corporation
# Copyright (c) 2016 Cadence Design Systems, Inc.
#
# SPDX-License-Identifier: Apache-2.0
#

# Include these first so that any properties (e.g. defaults) below can be
# overriden (by defining symbols in multiple locations)

# Note: $ARCH might be a glob pattern
source "arch/$(ARCH)/Kconfig"

choice
	prompt "Architecture"
	default X86

config ARC
	bool "ARC architecture"
	select HAS_DTS

config ARM
	bool "ARM architecture"
	select ARCH_HAS_THREAD_ABORT
	select HAS_DTS

config X86
	bool "x86 architecture"
	select ATOMIC_OPERATIONS_BUILTIN
	select HAS_DTS

config NIOS2
	bool "Nios II Gen 2 architecture"
	select ATOMIC_OPERATIONS_C
	select HAS_DTS

config RISCV32
	bool "RISCV32 architecture"
	select HAS_DTS

config XTENSA
	bool "Xtensa architecture"

config ARCH_POSIX
	bool "POSIX (native) architecture"
	select ATOMIC_OPERATIONS_BUILTIN
	select ARCH_HAS_CUSTOM_SWAP_TO_MAIN
	select ARCH_HAS_CUSTOM_BUSY_WAIT
	select ARCH_HAS_THREAD_ABORT
	select NATIVE_APPLICATION

endchoice


menu "General Architecture Options"

module = ARCH
module-str = arch
source "subsys/logging/Kconfig.template.log_config"

module = MPU
module-str = mpu
source "subsys/logging/Kconfig.template.log_config"

config BIG_ENDIAN
       bool
       help
         This option tells the build system that the target system is
         big-endian.  Little-endian architecture is the default and
         should leave this option unselected.  This option is selected
         by arch/$ARCH/Kconfig, soc/**/Kconfig, or boards/**/Kconfig
         and the user should generally avoid modifying it.  The option
         is used to select linker script OUTPUT_FORMAT and command
         line option for gen_isr_tables.py.

if ARCH_HAS_TRUSTED_EXECUTION

config TRUSTED_EXECUTION_SECURE
	bool "Trusted Execution: Secure firmware image"
	help
	  Select this option to enable building a Secure firmware
	  image for a platform that supports Trusted Execution. A
	  Secure firmware image will execute in Secure state. It may
	  allow the CPU to execute in Non-Secure (Normal) state.
	  Therefore, a Secure firmware image shall be able to
	  configure security attributions of CPU resources (memory
	  areas, peripherals, interrupts, etc.) as well as to handle
	  faults, related to security violations. It may optionally
	  allow certain functions to be called from the Non-Secure
	  (Normal) domain.

config TRUSTED_EXECUTION_NONSECURE
	depends on !TRUSTED_EXECUTION_SECURE
	bool "Trusted Execution: Non-Secure firmware image"
	help
	  Select this option to enable building a Non-Secure
	  firmware image for a platform that supports Trusted
	  Execution. A Non-Secure firmware image will execute
	  in Non-Secure (Normal) state. Therefore, it shall not
	  access CPU resources (memory areas, peripherals,
	  interrupts etc.) belonging to the Secure domain.

endif # ARCH_HAS_TRUSTED_EXECUTION

config HW_STACK_PROTECTION
	bool "Hardware Stack Protection"
	depends on ARCH_HAS_STACK_PROTECTION
	help
	  Select this option to enable hardware-based platform features to
	  catch stack overflows when the system is running in privileged
	  mode. If CONFIG_USERSPACE is not enabled, the system is always
	  running in privileged mode.

	  Note that this does not necessarily prevent corruption and assertions
	  about the overall system state when a fault is triggered cannot be
	  made.

config USERSPACE
	bool "User mode threads (EXPERIMENTAL)"
	depends on ARCH_HAS_USERSPACE
	help
	  When enabled, threads may be created or dropped down to user mode,
	  which has significantly restricted permissions and must interact
	  with the kernel via system calls. See Zephyr documentation for more
	  details	about this feature.

	  If a user thread overflows its stack, this will be caught and the
	  kernel itself will be shielded from harm. Enabling this option
	  may or may not catch stack overflows when the system is in
	  privileged mode or handling a system call; to ensure these are always
	  caught, enable CONFIG_HW_STACK_PROTECTION.

	  This feature is under heavy development and APIs related to it are
	  subject to change, even if declared non-private.

config PRIVILEGED_STACK_SIZE
	int "Size of privileged stack"
	default 512 if MPU_STACK_GUARD || BUILTIN_STACK_GUARD
	default 384 if ARC
	default 256
	depends on ARCH_HAS_USERSPACE
	help
	  This option sets the privileged stack region size that will be used
	  in addition to the user mode thread stack.  During normal execution,
	  this region will be inaccessible from user mode.  During system calls,
	  this region will be utilized by the system call.

config PRIVILEGED_STACK_TEXT_AREA
	int "Privileged stacks text area"
	default 256 if (DEBUG || STACK_CANARIES || CODE_DATA_RELOCATION)
	default 128
	depends on ARCH_HAS_USERSPACE
	help
	  Stack text area size for privileged stacks.

config KOBJECT_TEXT_AREA
	int "Size if kobject text area"
	default 256 if (!SIZE_OPTIMIZATIONS || STACK_CANARIES || ARC)
	default 256 if CODE_DATA_RELOCATION
	default 128
	depends on ARCH_HAS_USERSPACE
	help
	  Size of kernel object text area. Used in linker script.

config STACK_GROWS_UP
	bool "Stack grows towards higher memory addresses"
	help
	  Select this option if the architecture has upward growing thread
	  stacks. This is not common.

config MAX_THREAD_BYTES
	int "Bytes to use when tracking object thread permissions"
	default 2
	depends on USERSPACE
	help
	  Every kernel object will have an associated bitfield to store
	  thread permissions for that object. This controls the size of the
	  bitfield (in bytes) and imposes a limit on how many threads can
	  be created in the system.

config DYNAMIC_OBJECTS
	bool "Allow kernel objects to be allocated at runtime"
	depends on USERSPACE
	help
	Enabling this option allows for kernel objects to be requested from
	the calling thread's resource pool, at a slight cost in performance
	due to the supplemental run-time tables required to validate such
	objects.

	Objects allocated in this way can be freed with a supervisor-only
	API call, or when the number of references to that object drops to
	zero.

config SIMPLE_FATAL_ERROR_HANDLER
	bool "Simple system fatal error handler"
	default y if !MULTITHREADING
	help
	  Provides an implementation of _SysFatalErrorHandler() that hard hangs
	  instead of aborting the faulting thread, and does not print anything,
	  for footprint-concerned systems. Only enable this option if you do not
	  want debug capabilities in case of system fatal error.

if ARCH_HAS_NOCACHE_MEMORY_SUPPORT

config NOCACHE_MEMORY
	bool "Support for uncached memory"
	help
	  Add a "nocache" read-write memory section that is configured to
	  not be cached. This memory section can be used to perform DMA
	  transfers when cache coherence issues are not optimal or can not
	  be solved using cache maintenance operations.

endif # ARCH_HAS_NOCACHE_MEMORY_SUPPORT

menu "Interrupt Configuration"
#
# Interrupt related configs
#
config DYNAMIC_INTERRUPTS
	bool "Enable installation of IRQs at runtime"
	default n
	help
	  Enable installation of interrupts at runtime, which will move some
	  interrupt-related data structures to RAM instead of ROM, and
	  on some architectures increase code size.

config GEN_ISR_TABLES
	bool "Use generated IRQ tables"
	help
	  This option controls whether a platform uses the gen_isr_tables
	  script to generate its interrupt tables. This mechanism will create
	  an appropriate hardware vector table and/or software IRQ table.

config GEN_IRQ_VECTOR_TABLE
	bool "Generate an interrupt vector table"
	default y
	depends on GEN_ISR_TABLES
	help
	  This option controls whether a platform using gen_isr_tables
	  needs an interrupt vector table created. Only disable this if the
	  platform does not use a vector table at all, or requires the vector
	  table to be in a format that is not an array of function pointers
	  indexed by IRQ line. In the latter case, the vector table must be
	  supplied by the application or architecture code.

config GEN_SW_ISR_TABLE
	bool "Generate a software ISR table"
	default y
	depends on GEN_ISR_TABLES
	help
	  This option controls whether a platform using gen_isr_tables
	  needs a software ISR table table created. This is an array of struct
	  _isr_table_entry containing the interrupt service routine and supplied
	  parameter.

config GEN_IRQ_START_VECTOR
	int
	default 0
	depends on GEN_ISR_TABLES
	help
	  On some architectures, part of the vector table may be reserved for
	  system exceptions and is declared separately from the tables
	  created by gen_isr_tables.py. When creating these tables, this value
	  will be subtracted from CONFIG_NUM_IRQS to properly size them.
	  This is a hidden option which needs to be set per architecture and
	  left alone.


config IRQ_OFFLOAD
	bool "Enable IRQ offload"
	help
	  Enable irq_offload() API which allows functions to be synchronously
	  run in interrupt context. Mainly useful for test cases.

endmenu # Interrupt configuration

endmenu

#
# Architecture Capabilities
#
config ARCH_HAS_TRUSTED_EXECUTION
	bool

config ARCH_HAS_STACK_PROTECTION
	bool

config ARCH_HAS_USERSPACE
	bool

config ARCH_HAS_EXECUTABLE_PAGE_BIT
	bool

config ARCH_HAS_NOCACHE_MEMORY_SUPPORT
	bool

#
# Other architecture related options
#

config ARCH_HAS_THREAD_ABORT
	bool

#
# Hidden PM feature configs which are to be selected by
# individual SoC.
#
config SYS_POWER_LOW_POWER_STATE_SUPPORTED
	# Hidden
	bool
	help
	  This option signifies that the target supports the SYS_POWER_LOW_POWER_STATE
	  configuration option.

config SYS_POWER_STATE_CPU_LPS_SUPPORTED
	# Hidden
	bool
	help
	  This option signifies that the target supports the SYS_POWER_STATE_CPU_LPS
	  configuration option.

config SYS_POWER_STATE_CPU_LPS_1_SUPPORTED
	# Hidden
	bool
	help
	  This option signifies that the target supports the SYS_POWER_STATE_CPU_LPS_1
	  configuration option.

config SYS_POWER_STATE_CPU_LPS_2_SUPPORTED
	# Hidden
	bool
	help
	  This option signifies that the target supports the SYS_POWER_STATE_CPU_LPS_2
	  configuration option.

config SYS_POWER_DEEP_SLEEP_SUPPORTED
	# Hidden
	bool
	help
	  This option signifies that the target supports the SYS_POWER_DEEP_SLEEP
	  configuration option.

config SYS_POWER_STATE_DEEP_SLEEP_SUPPORTED
	# Hidden
	bool
	help
	  This option signifies that the target supports the SYS_POWER_STATE_DEEP_SLEEP
	  configuration option.

config SYS_POWER_STATE_DEEP_SLEEP_1_SUPPORTED
	# Hidden
	bool
	help
	  This option signifies that the target supports the SYS_POWER_STATE_DEEP_SLEEP_1
	  configuration option.

config SYS_POWER_STATE_DEEP_SLEEP_2_SUPPORTED
	# Hidden
	bool
	help
	  This option signifies that the target supports the SYS_POWER_STATE_DEEP_SLEEP_2
	  configuration option.

config BOOTLOADER_CONTEXT_RESTORE_SUPPORTED
	# Hidden
	bool
	help
	  This option signifies that the target has options of bootloaders
	  that support context restore upon resume from deep sleep


# End hidden CPU family configs
#

config CPU_HAS_TEE
	bool
	help
	  This option is enabled when the CPU has support for Trusted
	  Execution Environment (e.g. when it has a security attribution
	  unit).

config CPU_HAS_FPU
	bool
	help
	  This option is enabled when the CPU has hardware floating point
	  unit.

config CPU_HAS_MPU
	bool
	# Omit prompt to signify "hidden" option
	help
	  This option is enabled when the CPU has a Memory Protection Unit (MPU).

config MEMORY_PROTECTION
	bool
	# Omit prompt to signify "hidden" option
	help
	  This option is enabled when Memory Protection features are supported.
	  Memory protection support is currently available on ARC, ARM, and x86
	  architectures.

config MPU_REQUIRES_POWER_OF_TWO_ALIGNMENT
	bool
	# Omit prompt to signify "hidden" option
	help
	  This option is enabled when the MPU requires a power of two alignment
	  and size for MPU regions.


menu "Floating Point Options"
depends on CPU_HAS_FPU

config FLOAT
	bool "Floating point registers"
	help
	  This option allows threads to use the floating point registers.
	  By default, only a single thread may use the registers.

	  Disabling this option means that any thread that uses a
	  floating point register will get a fatal exception.

config FP_SHARING
	bool "Floating point register sharing"
	depends on FLOAT
	help
	  This option allows multiple threads to use the floating point
	  registers.

endmenu

#
# End hidden PM feature configs
#

config ARCH
	string
	help
	  System architecture string.

config SOC
	string
	help
	  SoC name which can be found under soc/<arch>/<soc name>.
	  This option holds the directory name used by the build system to locate
	  the correct linker and header files for the SoC.

config SOC_SERIES
	string
	help
	  SoC series name which can be found under soc/<arch>/<family>/<series>.
	  This option holds the directory name used by the build system to locate
	  the correct linker and header files.

config SOC_FAMILY
	string
	help
	  SoC family name which can be found under soc/<arch>/<family>.
	  This option holds the directory name used by the build system to locate
	  the correct linker and header files.

config BOARD
	string
	help
	  This option holds the name of the board and is used to locate the files
	  related to the board in the source tree (under boards/).
	  The Board is the first location where we search for a linker.ld file,
	  if not found we look for the linker file in
	  soc/<arch>/<family>/<series>