esp-idf/components/freertos/Kconfig

menu "FreeRTOS"

    config FREERTOS_UNICORE
        bool "Run FreeRTOS only on first core"
        default "y" if IDF_TARGET_ESP32S2
        select ESP_SYSTEM_SINGLE_CORE_MODE
        help
            This version of FreeRTOS normally takes control of all cores of
            the CPU. Select this if you only want to start it on the first core.
            This is needed when e.g. another process needs complete control
            over the second core.

            # This invisible config value sets the value of tskNO_AFFINITY in task.h.
            # Intended to be used as a constant from other Kconfig files.
            # Value is (32-bit) INT_MAX.

    config FREERTOS_NO_AFFINITY
        hex
        default 0x7FFFFFFF

    config FREERTOS_TICK_SUPPORT_CORETIMER
        bool
        default y if IDF_TARGET_ESP32 || IDF_TARGET_ESP32S2

    config FREERTOS_TICK_SUPPORT_SYSTIMER
        bool
        default y if !FREERTOS_TICK_SUPPORT_CORETIMER
        # ESP32-S3, ESP32-C3 and ESP32-H2 can use Systimer for FreeRTOS SysTick
        # ESP32S2 also has SYSTIMER but it can not be used for the FreeRTOS SysTick because:
        # - It has only one counter, which already in use esp_timer.
        #   A counter for SysTick should be stall in debug mode but work esp_timer.
        # - It is not possible to allocate two handlers for esp_timer and SysTick.

    choice FREERTOS_CORETIMER
        prompt "Xtensa timer to use as the FreeRTOS tick source"
        default FREERTOS_CORETIMER_0 if FREERTOS_TICK_SUPPORT_CORETIMER
        default FREERTOS_CORETIMER_SYSTIMER_LVL1 if FREERTOS_TICK_SUPPORT_SYSTIMER
        help
            FreeRTOS needs a timer with an associated interrupt to use as
            the main tick source to increase counters, run timers and do
            pre-emptive multitasking with. There are multiple timers available
            to do this, with different interrupt priorities. Check

        config FREERTOS_CORETIMER_0
            bool "Timer 0 (int 6, level 1)"
            depends on FREERTOS_TICK_SUPPORT_CORETIMER
            help
                Select this to use timer 0

        config FREERTOS_CORETIMER_1
            bool "Timer 1 (int 15, level 3)"
            depends on FREERTOS_TICK_SUPPORT_CORETIMER
            help
                Select this to use timer 1

        config FREERTOS_CORETIMER_SYSTIMER_LVL1
            bool "SYSTIMER 0 (level 1)"
            depends on FREERTOS_TICK_SUPPORT_SYSTIMER
            help
                Select this to use systimer with the 1 interrupt priority.

        config FREERTOS_CORETIMER_SYSTIMER_LVL3
            bool "SYSTIMER 0 (level 3)"
            depends on FREERTOS_TICK_SUPPORT_SYSTIMER
            help
                Select this to use systimer with the 3 interrupt priority.

    endchoice

    config FREERTOS_SYSTICK_USES_SYSTIMER
        bool
        default y if FREERTOS_CORETIMER_SYSTIMER_LVL1 || FREERTOS_CORETIMER_SYSTIMER_LVL3

    config FREERTOS_SYSTICK_USES_CCOUNT
        bool
        default y if FREERTOS_CORETIMER_0 || FREERTOS_CORETIMER_1

    config FREERTOS_OPTIMIZED_SCHEDULER
        bool "Enable FreeRTOS pĺatform optimized scheduler"
        depends on FREERTOS_UNICORE
        default y
        help
            On most platforms there are instructions can speedup the ready task
            searching. Enabling this option the FreeRTOS with this instructions
            support will be built.

    config FREERTOS_HZ
        int "Tick rate (Hz)"
        range 1 1000
        default 100
        help
            Select the tick rate at which FreeRTOS does pre-emptive context switching.

    config FREERTOS_ASSERT_ON_UNTESTED_FUNCTION
        bool "Halt when an SMP-untested function is called"
        default y
        help
            Some functions in FreeRTOS have not been thoroughly tested yet when moving to
            the SMP implementation of FreeRTOS. When this option is enabled, these fuctions
            will throw an assert().

    choice FREERTOS_CHECK_STACKOVERFLOW
        prompt "Check for stack overflow"
        default FREERTOS_CHECK_STACKOVERFLOW_CANARY
        help
            FreeRTOS can check for stack overflows in threads and trigger an user function
            called vApplicationStackOverflowHook when this happens.

        config FREERTOS_CHECK_STACKOVERFLOW_NONE
            bool "No checking"
            help
                Do not check for stack overflows (configCHECK_FOR_STACK_OVERFLOW=0)

        config FREERTOS_CHECK_STACKOVERFLOW_PTRVAL
            bool "Check by stack pointer value"
            help
                Check for stack overflows on each context switch by checking if
                the stack pointer is in a valid range. Quick but does not detect
                stack overflows that happened between context switches
                (configCHECK_FOR_STACK_OVERFLOW=1)

        config FREERTOS_CHECK_STACKOVERFLOW_CANARY
            bool "Check using canary bytes"
            help
                Places some magic bytes at the end of the stack area and on each
                context switch, check if these bytes are still intact. More thorough
                than just checking the pointer, but also slightly slower.
                (configCHECK_FOR_STACK_OVERFLOW=2)
    endchoice

    config FREERTOS_WATCHPOINT_END_OF_STACK
        bool "Set a debug watchpoint as a stack overflow check"
        default n
        help
            FreeRTOS can check if a stack has overflown its bounds by checking either the value of
            the stack pointer or by checking the integrity of canary bytes. (See FREERTOS_CHECK_STACKOVERFLOW
            for more information.) These checks only happen on a context switch, and the situation that caused
            the stack overflow may already be long gone by then. This option will use the last debug memory
            watchpoint to allow breaking into the debugger (or panic'ing) as soon as any
            of the last 32 bytes on the stack of a task are overwritten. The side effect is that using gdb, you
            effectively have one hardware watchpoint less because the last one is overwritten as soon as a task
            switch happens.

            Another consequence is that due to alignment requirements of the watchpoint, the usable stack size
            decreases by up to 60 bytes. This is because the watchpoint region has to be aligned to its size and the
            size for the stack watchpoint in IDF is 32 bytes.

            This check only triggers if the stack overflow writes within 32 bytes near the end of the stack, rather
            than overshooting further, so it is worth combining this approach with one of the other stack overflow
            check methods.

            When this watchpoint is hit, gdb will stop with a SIGTRAP message. When no JTAG OCD is attached, esp-idf
            will panic on an unhandled debug exception.

    config FREERTOS_INTERRUPT_BACKTRACE
        bool "Enable backtrace from interrupt to task context"
        default y
        help
            If this option is enabled, interrupt stack frame will be modified to
            point to the code of the interrupted task as its return address.
            This helps the debugger (or the panic handler) show a backtrace from
            the interrupt to the task which was interrupted. This also works for
            nested interrupts: higer level interrupt stack can be traced back to the
            lower level interrupt.
            This option adds 4 instructions to the interrupt dispatching code.

    config FREERTOS_THREAD_LOCAL_STORAGE_POINTERS
        int "Number of thread local storage pointers"
        range 1 256
        default 1
        help
            FreeRTOS has the ability to store per-thread pointers in the task
            control block. This controls the number of pointers available.

            This value must be at least 1. Index 0 is reserved for use by the pthreads API
            thread-local-storage. Other indexes can be used for any desired purpose.

    config FREERTOS_IDLE_TASK_STACKSIZE
        int "Idle Task stack size"
        range 768 32768
        default 1536
        help
            The idle task has its own stack, sized in bytes. The default size is enough for most uses. Size can be
            reduced to 768 bytes if no (or simple) FreeRTOS idle hooks are used and pthread local storage or FreeRTOS
            local storage cleanup callbacks are not used.

            The stack size may need to be increased above the default if the app installs idle or thread local storage
            cleanup hooks that use a lot of stack memory.

    config FREERTOS_ISR_STACKSIZE
        int "ISR stack size"
        range 2096 32768 if ESP_COREDUMP_DATA_FORMAT_ELF
        default 2096 if ESP_COREDUMP_DATA_FORMAT_ELF
        range 1536 32768
        default 1536
        help
            The interrupt handlers have their own stack. The size of the stack can be defined here.
            Each processor has its own stack, so the total size occupied will be twice this.

    config FREERTOS_LEGACY_HOOKS
        bool "Use FreeRTOS legacy hooks"
        default n
        help
            FreeRTOS offers a number of hooks/callback functions that are called when a timer
            tick happens, the idle thread runs etc. esp-idf replaces these by runtime registerable
            hooks using the esp_register_freertos_xxx_hook system, but for legacy reasons the old
            hooks can also still be enabled. Please enable this only if you have code that for some
            reason can't be migrated to the esp_register_freertos_xxx_hook system.

    config FREERTOS_MAX_TASK_NAME_LEN
        int "Maximum task name length"
        range 1 256
        default 16
        help
            Changes the maximum task name length. Each task allocated will
            include this many bytes for a task name. Using a shorter value
            saves a small amount of RAM, a longer value allows more complex
            names.

            For most uses, the default of 16 is OK.

    config FREERTOS_ENABLE_BACKWARD_COMPATIBILITY
        bool "Support legacy FreeRTOS API"
        default n
        help
            This option enables the configENABLE_BACKWARD_COMPATIBILITY option, thus allowing the usage
            of legacy function names and types present in versions prior to FreeRTOS v8.0.0.

    config FREERTOS_SUPPORT_STATIC_ALLOCATION
        # Always enabled.
        # Kconfig option preserved for compatibility with code
        # which checked for CONFIG_FREERTOS_SUPPORT_STATIC_ALLOCATION.
        bool
        default y

    config FREERTOS_ENABLE_STATIC_TASK_CLEAN_UP
        bool "Enable static task clean up hook"
        default n
        help
            Enable this option to make FreeRTOS call the static task clean up hook when a task is deleted.

            Bear in mind that if this option is enabled you will need to implement the following function::

                void vPortCleanUpTCB ( void *pxTCB ) {
                    // place clean up code here
                }

    config FREERTOS_TIMER_TASK_PRIORITY
        int "FreeRTOS timer task priority"
        range 1 25
        default 1
        help
            The timer service task (primarily) makes use of existing FreeRTOS features, allowing timer
            functionality to be added to an application with minimal impact on the size of the application's
            executable binary.

            Use this constant to define the priority that the timer task will run at.

    config FREERTOS_TIMER_TASK_STACK_DEPTH
        int "FreeRTOS timer task stack size"
        range 1536 32768
        default 2048
        help
            The timer service task (primarily) makes use of existing FreeRTOS features, allowing timer
            functionality to be added to an application with minimal impact on the size of the application's
            executable binary.

            Use this constant to define the size (in bytes) of the stack allocated for the timer task.

    config FREERTOS_TIMER_QUEUE_LENGTH
        int "FreeRTOS timer queue length"
        range 5 20
        default 10
        help
            FreeRTOS provides a set of timer related API functions. Many of these functions use a standard
            FreeRTOS queue to send commands to the timer service task. The queue used for this purpose is
            called the 'timer command queue'. The 'timer command queue' is private to the FreeRTOS timer
            implementation, and cannot be accessed directly.

            For most uses the default value of 10 is OK.

    config FREERTOS_QUEUE_REGISTRY_SIZE
        int "FreeRTOS queue registry size"
        range 0 20
        default 0
        help
            FreeRTOS uses the queue registry as a means for kernel aware debuggers to locate queues, semaphores,
            and mutexes. The registry allows for a textual name to be associated with a queue for easy identification
            within a debugging GUI. A value of 0 will disable queue registry functionality, and a value larger than 0
            will specify the number of queues/semaphores/mutexes that the registry can hold.

    config FREERTOS_USE_TRACE_FACILITY
        bool "Enable FreeRTOS trace facility"
        default n
        help
            If enabled, configUSE_TRACE_FACILITY will be defined as 1 in FreeRTOS.
            This will allow the usage of trace facility functions such as
            uxTaskGetSystemState().

    config FREERTOS_USE_STATS_FORMATTING_FUNCTIONS
        bool "Enable FreeRTOS stats formatting functions"
        depends on FREERTOS_USE_TRACE_FACILITY
        default n
        help
            If enabled, configUSE_STATS_FORMATTING_FUNCTIONS will be defined as 1 in
            FreeRTOS. This will allow the usage of stats formatting functions such
            as vTaskList().

    config FREERTOS_VTASKLIST_INCLUDE_COREID
        bool "Enable display of xCoreID in vTaskList"
        depends on FREERTOS_USE_STATS_FORMATTING_FUNCTIONS
        default n
        help
            If enabled, this will include an extra column when vTaskList is called
            to display the CoreID the task is pinned to (0,1) or -1 if not pinned.

    config FREERTOS_GENERATE_RUN_TIME_STATS
        bool "Enable FreeRTOS to collect run time stats"
        default n
        select FREERTOS_USE_TRACE_FACILITY
        select FREERTOS_USE_STATS_FORMATTING_FUNCTIONS
        help
            If enabled, configGENERATE_RUN_TIME_STATS will be defined as 1 in
            FreeRTOS. This will allow FreeRTOS to collect information regarding the
            usage of processor time amongst FreeRTOS tasks. Run time stats are
            generated using either the ESP Timer or the CPU Clock as the clock
            source (Note that run time stats are only valid until the clock source
            overflows). The function vTaskGetRunTimeStats() will also be available
            if FREERTOS_USE_STATS_FORMATTING_FUNCTIONS and
            FREERTOS_USE_TRACE_FACILITY are enabled. vTaskGetRunTimeStats() will
            display the run time of each task as a % of the total run time of all
            CPUs (task run time / no of CPUs) / (total run time / 100 )


    choice FREERTOS_RUN_TIME_STATS_CLK
        prompt "Choose the clock source for run time stats"
        depends on FREERTOS_GENERATE_RUN_TIME_STATS
        default FREERTOS_RUN_TIME_STATS_USING_ESP_TIMER
        help
            Choose the clock source for FreeRTOS run time stats. Options are CPU0's
            CPU Clock or the ESP Timer. Both clock sources are 32 bits. The CPU
            Clock can run at a higher frequency hence provide a finer resolution
            but will overflow much quicker. Note that run time stats are only valid
            until the clock source overflows.

        config FREERTOS_RUN_TIME_STATS_USING_ESP_TIMER
            bool "Use ESP TIMER for run time stats"
            help
                ESP Timer will be used as the clock source for FreeRTOS run time stats.
                The ESP Timer runs at a frequency of 1MHz regardless of Dynamic
                Frequency Scaling. Therefore the ESP Timer will overflow in
                approximately 4290 seconds.

        config FREERTOS_RUN_TIME_STATS_USING_CPU_CLK
            bool "Use CPU Clock for run time stats"
            depends on FREERTOS_SYSTICK_USES_CCOUNT
            help
                CPU Clock will be used as the clock source for the generation of run
                time stats. The CPU Clock has a frequency dependent on
                ESP32_DEFAULT_CPU_FREQ_MHZ and Dynamic Frequency Scaling (DFS).
                Therefore the CPU Clock frequency can fluctuate between 80 to 240MHz.
                Run time stats generated using the CPU Clock represents the number of
                CPU cycles each task is allocated and DOES NOT reflect the amount of
                time each task runs for (as CPU clock frequency can change). If the CPU
                clock consistently runs at the maximum frequency of 240MHz, it will
                overflow in approximately 17 seconds.

    endchoice

    config FREERTOS_USE_TICKLESS_IDLE
        bool "Tickless idle support"
        depends on PM_ENABLE
        default n
        help
            If power management support is enabled, FreeRTOS will be able to put
            the system into light sleep mode when no tasks need to run for a number
            of ticks. This number can be set using FREERTOS_IDLE_TIME_BEFORE_SLEEP option.
            This feature is also known as "automatic light sleep".

            Note that timers created using esp_timer APIs may prevent the system from
            entering sleep mode, even when no tasks need to run.
            To skip unnecessary wake-up initialize a timer with the "skip_unhandled_events" option as true.

            If disabled, automatic light sleep support will be disabled.

    config FREERTOS_IDLE_TIME_BEFORE_SLEEP
        int "Minimum number of ticks to enter sleep mode for"
        depends on FREERTOS_USE_TICKLESS_IDLE
        default 3
        range 2 4294967295
        # Minimal value is 2 because of a check in FreeRTOS.h (search configEXPECTED_IDLE_TIME_BEFORE_SLEEP)
        help
            FreeRTOS will enter light sleep mode if no tasks need to run for this number
            of ticks.

    config FREERTOS_TASK_FUNCTION_WRAPPER
        bool "Enclose all task functions in a wrapper function"
        depends on COMPILER_OPTIMIZATION_DEFAULT || ESP_COREDUMP_ENABLE || ESP_GDBSTUB_ENABLED
        default y
        help
            If enabled, all FreeRTOS task functions will be enclosed in a wrapper function.
            If a task function mistakenly returns (i.e. does not delete), the call flow will
            return to the wrapper function. The wrapper function will then log an error and
            abort the application. This option is also required for GDB backtraces and C++
            exceptions to work correctly inside top-level task functions.

    config FREERTOS_CHECK_MUTEX_GIVEN_BY_OWNER
        bool "Check that mutex semaphore is given by owner task"
        default y
        help
            If enabled, assert that when a mutex semaphore is given, the task giving the
            semaphore is the task which is currently holding the mutex.

    config FREERTOS_CHECK_PORT_CRITICAL_COMPLIANCE
        bool "Tests compliance with Vanilla FreeRTOS port*_CRITICAL calls"
        default n
        help
            If enabled, context of port*_CRITICAL calls (ISR or Non-ISR)
            would be checked to be in compliance with Vanilla FreeRTOS.
            e.g Calling port*_CRITICAL from ISR context would cause assert failure

    config FREERTOS_PLACE_FUNCTIONS_INTO_FLASH
        bool "Place FreeRTOS functions into Flash"
        default n
        help
            When enabled the selected Non-ISR FreeRTOS functions will be placed into Flash memory instead of IRAM.
            This saves up to 8KB of IRAM depending on which functions are used.

    config FREERTOS_DEBUG_OCDAWARE
        bool
        help
            Hidden option, gets selected by CONFIG_ESPxx_DEBUG_OCDAWARE

    config FREERTOS_FPU_IN_ISR
        bool "Allow use of float inside Level 1 ISR (EXPERIMENTAL)"
        depends on IDF_TARGET_ESP32
        default n
        help
            When enabled, the usage of float type is allowed inside Level 1
            ISRs.

    config FREERTOS_ENABLE_TASK_SNAPSHOT
        bool "Enable task snapshot functions"
        default y
        help
            When enabled, the functions related to snapshots, such as vTaskGetSnapshot or uxTaskGetSnapshotAll,
            are compiled and linked.

    config FREERTOS_PLACE_SNAPSHOT_FUNS_INTO_FLASH
        bool "Place task snapshot functions into flash"
        default n
        depends on FREERTOS_ENABLE_TASK_SNAPSHOT && !ESP_PANIC_HANDLER_IRAM
        help
            When enabled, the functions related to snapshots, such as vTaskGetSnapshot or uxTaskGetSnapshotAll,
            will be placed in flash. Note that if enabled, these functions cannot be called when cache is disabled.
endmenu