# 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"