zephyr/kernel/Kconfig

# Kconfig - kernel configuration options

#
# Copyright (c) 2014-2015 Wind River Systems, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#


menu "General Kernel Options"

config SYS_CLOCK_TICKS_PER_SEC
	int
	prompt "System tick frequency (in ticks/second)"
	default 100
	help
	This option specifies the frequency of the system clock in Hz.

config SYS_CLOCK_HW_CYCLES_PER_SEC
	int "System clock's h/w timer frequency"
	help
	This option specifies the frequency of the hardware timer used for the
	system clock (in Hz). This option is set by the board's Kconfig file
	and the user should generally avoid modifying it via the menu configuration.

config SYS_CLOCK_EXISTS
	bool
	# omit prompt to signify a "hidden" option
	default y
	default n if (SYS_CLOCK_TICKS_PER_SEC = 0)
	help
	This option specifies that the kernel lacks timer support.

config INIT_STACKS
	bool
	prompt "Initialize stack areas"
	default n
	help
	This option instructs the kernel to initialize stack areas with a
	known value (0xaa) before they are first used, so that the high
	water mark can be easily determined. This applies to the stack areas
	for both tasks and fibers, as well as for the microkernel server's command
	stack.

config XIP
	bool
	prompt "Execute in place"
	help
	  This option allows the kernel to operate with its text and read-only
	  sections residing in ROM (or similar read-only memory). Not all boards
	  support this option so it must be used with care; you must also
	  supply a linker command file when building your image. Enabling this
	  option increases both the code and data footprint of the image.

config RING_BUFFER
	bool
	prompt "Enable ring buffers"
	default n
	help
	Enable usage of ring buffers. Similar to nanokernel FIFOs but manage
	their own buffer memory and can store arbitrary data. For optimal
	performance, use buffer sizes that are a power of 2.

config THREAD_MONITOR
	bool
	prompt "Thread monitoring [EXPERIMENTAL]"
	default n
	help
	  This option instructs the kernel to maintain a list of all threads
	  (excluding those that have not yet started or have already
	  terminated).

config KERNEL_INIT_PRIORITY_OBJECTS
	int
	prompt "Kernel objects initialization priority"
	default 30
	help
	Kernel objects use this priority for initialization. This
	priority needs to be higher than minimal default initialization
	priority.

config KERNEL_INIT_PRIORITY_DEFAULT
	int
	prompt "Default init priority"
	default 40
	help
	Defaut minimal init priority for each init level.

config KERNEL_INIT_PRIORITY_DEVICE
	int
	prompt "Default init priority for device drivers"
	default 50
	help
	Device driver, that depends on common components, such as
	interrupt controller, but does not depend on other devices,
	uses this init priority.

config APPLICATION_INIT_PRIORITY
	int
	prompt "Default init priority for application level drivers"
	default 90
	help
	This priority level is for end-user drivers such as sensors and display
	which have no inward dependencies.

menu "Security Options"

config STACK_CANARIES
	bool
	prompt "Compiler stack canaries"
	default n
	help
	This option enables compiler stack canaries support kernel functions.

	If stack canaries are supported by the compiler, it will emit
	extra code that inserts a canary value into the stack frame when
	a function is entered and validates this value upon exit.
	Stack corruption (such as that caused by buffer overflow) results
	in a fatal error condition for the running entity.
	Enabling this option can result in a significant increase
	in footprint and an associated decrease in performance.

	If stack canaries are not supported by the compiler, enabling this
	option has no effect.
endmenu

endmenu

source "kernel/unified/Kconfig"

config MDEF
	bool
	prompt "Use MDEF files for statically configured kernel objects"
	default y
	help
	Using an MDEF file can help the startup time of the application since
	the objects it lists are statically allocated and initialized, and may
	also reduce code size if no subsystem uses the initialization routines.

	Disabling this option can reduce the compilation time slightly.

	In doubt, select 'y'.

source "kernel/Kconfig.event_logger"
source "kernel/Kconfig.power_mgmt"