zephyr/arch/arm/core/Kconfig

# Kconfig - ARM core configuration options

#
# Copyright (c) 2015 Wind River Systems, Inc.
#
# SPDX-License-Identifier: Apache-2.0
#

config CPU_CORTEX
	bool
	# Omit prompt to signify "hidden" option
	help
	  This option signifies the use of a CPU of the Cortex family.

config CPU_CORTEX_M
	bool
	# Omit prompt to signify "hidden" option
	select CPU_CORTEX
	select ARCH_HAS_CUSTOM_SWAP_TO_MAIN
	select HAS_CMSIS
	select HAS_FLASH_LOAD_OFFSET
	select ARCH_HAS_TRUSTED_EXECUTION if ARM_TRUSTZONE_M
	select ARCH_HAS_STACK_PROTECTION if ARM_MPU || CPU_CORTEX_M_HAS_SPLIM
	select ARCH_HAS_USERSPACE if ARM_MPU
	select ARCH_HAS_NOCACHE_MEMORY_SUPPORT if ARM_MPU && CPU_HAS_ARM_MPU && CPU_CORTEX_M7
	select ARCH_HAS_RAMFUNC_SUPPORT
	select SWAP_NONATOMIC
	help
	  This option signifies the use of a CPU of the Cortex-M family.

config CPU_HAS_SYSTICK
	bool
	# Omit prompt to signify "hidden" option
	help
	  This option is enabled when the CPU has systick timer implemented.

config BUILTIN_STACK_GUARD
	bool "Thread Stack Guards based on built-in ARM stack limit checking"
	depends on CPU_CORTEX_M_HAS_SPLIM
	select THREAD_STACK_INFO
	help
	  Enable Thread/Interrupt Stack Guards via built-in Stack Pointer
	  limit checking. The functionality must be supported by HW.

config ARM_STACK_PROTECTION
	bool
	default y if HW_STACK_PROTECTION
	select BUILTIN_STACK_GUARD if CPU_CORTEX_M_HAS_SPLIM
	select MPU_STACK_GUARD if (!BUILTIN_STACK_GUARD && ARM_MPU)
	help
	  This option enables either:
	  - The built-in Stack Pointer limit checking, or
	  - the MPU-based stack guard
	  to cause a system fatal error
	  if the bounds of the current process stack are overflowed.
	  The two stack guard options are mutually exclusive. The
	  selection of the built-in Stack Pointer limit checking is
	  prioritized over the MPU-based stack guard.

config ARM_SECURE_FIRMWARE
	bool
	depends on ARMV8_M_SE
	default y if TRUSTED_EXECUTION_SECURE
	help
	  This option indicates that we are building a Zephyr image that
	  is intended to execute in Secure state. The option is only
	  applicable to ARMv8-M MCUs that implement the Security Extension.

	  This option enables Zephyr to include code that executes in
	  Secure state, as well as to exclude code that is designed to
	  execute only in Non-secure state.

	  Code executing in Secure state has access to both the Secure
	  and Non-Secure resources of the Cortex-M MCU.

	  Code executing in Non-Secure state may trigger Secure Faults,
	  if Secure MCU resources are accessed from the Non-Secure state.
	  Secure Faults may only be handled by code executing in Secure
	  state.

config ARM_NONSECURE_FIRMWARE
	bool
	depends on !ARM_SECURE_FIRMWARE
	depends on ARMV8_M_SE
	default y if TRUSTED_EXECUTION_NONSECURE
	help
	  This option indicates that we are building a Zephyr image that
	  is intended to execute in Non-Secure state. Execution of this
	  image is triggered by Secure firmware that executes in Secure
	  state. The option is only applicable to ARMv8-M MCUs that
	  implement the Security Extension.

	  This option enables Zephyr to include code that executes in
	  Non-Secure state only, as well as to exclude code that is
	  designed to execute only in Secure state.

	  Code executing in Non-Secure state has no access to Secure
	  resources of the Cortex-M MCU, and, therefore, it shall avoid
	  accessing them.

menu "ARM Secure Firmware Options"
depends on ARM_SECURE_FIRMWARE

config ARM_FIRMWARE_HAS_SECURE_ENTRY_FUNCS
	bool "Secure Firmware has Secure Entry functions"
	depends on ARM_SECURE_FIRMWARE
	help
	  Option indicates that ARM Secure Firmware contains
	  Secure Entry functions that may be called from
	  Non-Secure state. Secure Entry functions must be
	  located in Non-Secure Callable memory regions.

config ARM_NSC_REGION_BASE_ADDRESS
	hex "ARM Non-Secure Callable Region base address"
	depends on ARM_FIRMWARE_HAS_SECURE_ENTRY_FUNCS
	default 0
	help
	  Start address of Non-Secure Callable section.

	  Notes:
	  - The default value (i.e. when the user does not configure
	  the option explicitly) instructs the linker script to
	  place the Non-Secure Callable section, automatically,
	  inside the .text area.
	  - Certain requirements/restrictions may apply regarding
	  the size and the alignment of the starting address for
	  a Non-Secure Callable section, depending on the available
	  security attribution unit (SAU or IDAU) for a given SOC.

config ARM_ENTRY_VENEERS_LIB_NAME
	string "Entry Veneers symbol file"
	depends on ARM_FIRMWARE_HAS_SECURE_ENTRY_FUNCS
	default "libentryveneers.a"
	help
	  Library file to store the symbol table for
	  the entry veneers. The library may be used
	  for building a Non-Secure firmware with
	  access to Secure Entry functions.

endmenu

menu "Architecture Floating Point Options"
depends on CPU_HAS_FPU

choice
	prompt "Floating point ABI"
	default FP_HARDABI
	depends on FLOAT

config FP_HARDABI
	bool "Floating point Hard ABI"
	help
	  This option selects the Floating point ABI in which hardware floating
	  point instructions are generated and uses FPU-specific calling
	  conventions

config FP_SOFTABI
	bool "Floating point Soft ABI"
	help
	  This option selects the Floating point ABI in which hardware floating
	  point instructions are generated but soft-float calling conventions.

endchoice

endmenu

source "arch/arm/core/cortex_m/Kconfig"

if CPU_HAS_MPU
source "arch/arm/core/cortex_m/mpu/Kconfig"
endif

if CPU_HAS_TEE
source "arch/arm/core/cortex_m/tz/Kconfig"
endif