esp-idf/components/esp_system/Kconfig

menu "ESP System Settings"
    # Insert chip-specific cpu config
    rsource "./port/soc/$IDF_TARGET/Kconfig.cpu"

    orsource "./port/soc/$IDF_TARGET/Kconfig.cache"

    orsource "./port/soc/$IDF_TARGET/Kconfig.memory"

    orsource "./port/soc/$IDF_TARGET/Kconfig.tracemem"

    choice ESP_SYSTEM_PANIC
        prompt "Panic handler behaviour"
        default ESP_SYSTEM_PANIC_PRINT_REBOOT
        help
            If FreeRTOS detects unexpected behaviour or an unhandled exception, the panic handler is
            invoked. Configure the panic handler's action here.

        config ESP_SYSTEM_PANIC_PRINT_HALT
            bool "Print registers and halt"
            depends on !ESP_SYSTEM_GDBSTUB_RUNTIME
            help
                Outputs the relevant registers over the serial port and halt the
                processor. Needs a manual reset to restart.

        config ESP_SYSTEM_PANIC_PRINT_REBOOT
            bool "Print registers and reboot"
            depends on !ESP_SYSTEM_GDBSTUB_RUNTIME
            help
                Outputs the relevant registers over the serial port and immediately
                reset the processor.

        config ESP_SYSTEM_PANIC_SILENT_REBOOT
            bool "Silent reboot"
            depends on !ESP_SYSTEM_GDBSTUB_RUNTIME
            help
                Just resets the processor without outputting anything

        config ESP_SYSTEM_PANIC_GDBSTUB
            bool "GDBStub on panic"
            select ESP_GDBSTUB_ENABLED
            help
                Invoke gdbstub on the serial port, allowing for gdb to attach to it to do a postmortem
                of the crash.

    endchoice

    config ESP_SYSTEM_PANIC_REBOOT_DELAY_SECONDS
        int "Panic reboot delay (Seconds)"
        default 0
        range 0 99
        depends on ESP_SYSTEM_PANIC_PRINT_REBOOT
        help
            After the panic handler executes, you can specify a number of seconds to
            wait before the device reboots.

    config ESP_SYSTEM_SINGLE_CORE_MODE
        bool
        default n
        help
            Only initialize and use the main core.

    config ESP_SYSTEM_RTC_EXT_XTAL
        # This is a High Layer Kconfig option, invisible, can be selected by other Kconfig option
        # e.g. It will be selected on when RTC_CLK_SRC_EXT_CRYS is on
        bool
        default n

    config ESP_SYSTEM_RTC_EXT_OSC
        # This is a High Layer Kconfig option, invisible, can be selected by other Kconfig option
        # e.g. It will be selected on when ESPX_RTC_CLK_SRC_EXT_OSC is on
        bool
        default n

    config ESP_SYSTEM_RTC_EXT_XTAL_BOOTSTRAP_CYCLES
        int "Bootstrap cycles for external 32kHz crystal"
        depends on ESP_SYSTEM_RTC_EXT_XTAL
        default 5 if IDF_TARGET_ESP32
        default 0
        range 0 32768
        help
            To reduce the startup time of an external RTC crystal,
            we bootstrap it with a 32kHz square wave for a fixed number of cycles.
            Setting 0 will disable bootstrapping (if disabled, the crystal may take
            longer to start up or fail to oscillate under some conditions).

            If this value is too high, a faulty crystal may initially start and then fail.
            If this value is too low, an otherwise good crystal may not start.

            To accurately determine if the crystal has started,
            set a larger "Number of cycles for RTC_SLOW_CLK calibration" (about 3000).

    config ESP_SYSTEM_RTC_FAST_MEM_AS_HEAP_DEPCHECK
        bool
        default y if IDF_TARGET_ESP32 && FREERTOS_UNICORE
        default y if IDF_TARGET_ESP32S2
        default y if IDF_TARGET_ESP32C3
        default y if IDF_TARGET_ESP32S3
        default y if IDF_TARGET_ESP32C6
        default n if IDF_TARGET_ESP32H2 # IDF-5667
        default y if IDF_TARGET_ESP32P4
        depends on SOC_RTC_FAST_MEM_SUPPORTED

    config ESP_SYSTEM_ALLOW_RTC_FAST_MEM_AS_HEAP
        bool "Enable RTC fast memory for dynamic allocations"
        default y
        depends on ESP_SYSTEM_RTC_FAST_MEM_AS_HEAP_DEPCHECK
        help
            This config option allows to add RTC fast memory region to system heap with capability
            similar to that of DRAM region but without DMA. This memory will be consumed first per
            heap initialization order by early startup services and scheduler related code. Speed
            wise RTC fast memory operates on APB clock and hence does not have much performance impact.

    config ESP_SYSTEM_USE_EH_FRAME
        bool "Generate and use eh_frame for backtracing"
        default n
        depends on IDF_TARGET_ARCH_RISCV
        help
            Generate DWARF information for each function of the project. These information will parsed and used to
            perform backtracing when panics occur. Activating this option will activate asynchronous frame unwinding
            and generation of both .eh_frame and .eh_frame_hdr sections, resulting in a bigger binary size (20% to
            100% larger). The main purpose of this option is to be able to have a backtrace parsed and printed by
            the program itself, regardless of the serial monitor used.
            This option shall NOT be used for production.

    menu "Memory protection"

        config ESP_SYSTEM_PMP_IDRAM_SPLIT
            bool "Enable IRAM/DRAM split protection"
            depends on SOC_CPU_IDRAM_SPLIT_USING_PMP
            default "y"
            help
                If enabled, the CPU watches all the memory access and raises an exception in case
                of any memory violation. This feature automatically splits
                the SRAM memory, using PMP, into data and instruction segments and sets Read/Execute permissions
                for the instruction part (below given splitting address) and Read/Write permissions
                for the data part (above the splitting address). The memory protection is effective
                on all access through the IRAM0 and DRAM0 buses.

        config ESP_SYSTEM_MEMPROT_FEATURE
            bool "Enable memory protection"
            depends on SOC_MEMPROT_SUPPORTED
            default "y"
            help
                If enabled, the permission control module watches all the memory access and fires the panic handler
                if a permission violation is detected. This feature automatically splits
                the SRAM memory into data and instruction segments and sets Read/Execute permissions
                for the instruction part (below given splitting address) and Read/Write permissions
                for the data part (above the splitting address). The memory protection is effective
                on all access through the IRAM0 and DRAM0 buses.

        config ESP_SYSTEM_MEMPROT_FEATURE_LOCK
            depends on ESP_SYSTEM_MEMPROT_FEATURE
            bool "Lock memory protection settings"
            default "y"
            help
                Once locked, memory protection settings cannot be changed anymore.
                The lock is reset only on the chip startup.

    endmenu  # Memory protection

    config ESP_SYSTEM_EVENT_QUEUE_SIZE
        int "System event queue size"
        default 32
        help
            Config system event queue size in different application.

    config ESP_SYSTEM_EVENT_TASK_STACK_SIZE
        int "Event loop task stack size"
        default 2304
        help
            Config system event task stack size in different application.

    config ESP_MAIN_TASK_STACK_SIZE
        int "Main task stack size"
        default 3584
        help
            Configure the "main task" stack size. This is the stack of the task
            which calls app_main(). If app_main() returns then this task is deleted
            and its stack memory is freed.

    choice ESP_MAIN_TASK_AFFINITY
        prompt "Main task core affinity"
        default ESP_MAIN_TASK_AFFINITY_CPU0
        help
            Configure the "main task" core affinity. This is the used core of the task
            which calls app_main(). If app_main() returns then this task is deleted.

        config ESP_MAIN_TASK_AFFINITY_CPU0
            bool "CPU0"
        config ESP_MAIN_TASK_AFFINITY_CPU1
            bool "CPU1"
            depends on !FREERTOS_UNICORE
        config ESP_MAIN_TASK_AFFINITY_NO_AFFINITY
            bool "No affinity"

    endchoice

    config ESP_MAIN_TASK_AFFINITY
        hex
        default 0x0 if ESP_MAIN_TASK_AFFINITY_CPU0
        default 0x1 if ESP_MAIN_TASK_AFFINITY_CPU1
        default FREERTOS_NO_AFFINITY if ESP_MAIN_TASK_AFFINITY_NO_AFFINITY

    config ESP_MINIMAL_SHARED_STACK_SIZE
        int "Minimal allowed size for shared stack"
        default 2048
        help
            Minimal value of size, in bytes, accepted to execute a expression
            with shared stack.

    choice ESP_CONSOLE_UART
        prompt "Channel for console output"
        default ESP_CONSOLE_UART_DEFAULT
        help
            Select where to send console output (through stdout and stderr).

            - Default is to use UART0 on pre-defined GPIOs.
            - If "Custom" is selected, UART0 or UART1 can be chosen,
              and any pins can be selected.
            - If "None" is selected, there will be no console output on any UART, except
              for initial output from ROM bootloader. This ROM output can be suppressed by
              GPIO strapping or EFUSE, refer to chip datasheet for details.
            - On chips with USB OTG peripheral, "USB CDC" option redirects output to the
              CDC port. This option uses the CDC driver in the chip ROM.
              This option is incompatible with TinyUSB stack.
            - On chips with an USB serial/JTAG debug controller, selecting the option
              for that redirects output to the CDC/ACM (serial port emulation) component
              of that device.
        config ESP_CONSOLE_UART_DEFAULT
            bool "Default: UART0"
        config ESP_CONSOLE_USB_CDC
            bool "USB CDC"
            # && !TINY_USB is because the ROM CDC driver is currently incompatible with TinyUSB.
            depends on (IDF_TARGET_ESP32S2 || IDF_TARGET_ESP32S3)  && !TINY_USB
        config ESP_CONSOLE_USB_SERIAL_JTAG
            bool "USB Serial/JTAG Controller"
            select ESPTOOLPY_NO_STUB if IDF_TARGET_ESP32C3  #ESPTOOL-252
            depends on SOC_USB_SERIAL_JTAG_SUPPORTED
        config ESP_CONSOLE_UART_CUSTOM
            bool "Custom UART"
        config ESP_CONSOLE_NONE
            bool "None"
    endchoice

    choice ESP_CONSOLE_SECONDARY
        depends on SOC_USB_SERIAL_JTAG_SUPPORTED
        prompt "Channel for console secondary output"
        default ESP_CONSOLE_SECONDARY_USB_SERIAL_JTAG
        help
            This secondary option supports output through other specific port like USB_SERIAL_JTAG
            when UART0 port as a primary is selected but not connected. This secondary output currently only supports
            non-blocking mode without using REPL. If you want to output in blocking mode with REPL or
            input through this secondary port, please change the primary config to this port
            in `Channel for console output` menu.
        config ESP_CONSOLE_SECONDARY_NONE
            bool "No secondary console"
        config ESP_CONSOLE_SECONDARY_USB_SERIAL_JTAG
            bool "USB_SERIAL_JTAG PORT"
            depends on !ESP_CONSOLE_USB_SERIAL_JTAG
            help
                This option supports output through USB_SERIAL_JTAG port when the UART0 port is not connected.
                The output currently only supports non-blocking mode without using the console.
                If you want to output in blocking mode with REPL or input through USB_SERIAL_JTAG port,
                please change the primary config to ESP_CONSOLE_USB_SERIAL_JTAG above.
    endchoice

    config ESP_CONSOLE_USB_SERIAL_JTAG_ENABLED
        # Internal option, indicates that console USB SERIAL JTAG is used
        bool
        default y if ESP_CONSOLE_USB_SERIAL_JTAG || ESP_CONSOLE_SECONDARY_USB_SERIAL_JTAG

    config ESP_CONSOLE_UART
        # Internal option, indicates that console UART is used (and not USB, for example)
        bool
        default y if ESP_CONSOLE_UART_DEFAULT || ESP_CONSOLE_UART_CUSTOM

    choice ESP_CONSOLE_UART_NUM
        prompt "UART peripheral to use for console output (0-1)"
        depends on ESP_CONSOLE_UART_CUSTOM
        default ESP_CONSOLE_UART_CUSTOM_NUM_0
        help
            This UART peripheral is used for console output from the ESP-IDF Bootloader and the app.

            If the configuration is different in the Bootloader binary compared to the app binary, UART
            is reconfigured after the bootloader exits and the app starts.

            Due to an ESP32 ROM bug, UART2 is not supported for console output
            via esp_rom_printf.

        config ESP_CONSOLE_UART_CUSTOM_NUM_0
            bool "UART0"
        config ESP_CONSOLE_UART_CUSTOM_NUM_1
            bool "UART1"
    endchoice

    config ESP_CONSOLE_UART_NUM
        int
        default 0 if ESP_CONSOLE_UART_DEFAULT
        default 0 if ESP_CONSOLE_UART_CUSTOM_NUM_0
        default 1 if ESP_CONSOLE_UART_CUSTOM_NUM_1
        default -1 if !ESP_CONSOLE_UART

    config ESP_CONSOLE_UART_TX_GPIO
        int "UART TX on GPIO#"
        depends on ESP_CONSOLE_UART_CUSTOM
        range 0 SOC_GPIO_OUT_RANGE_MAX
        default 1 if IDF_TARGET_ESP32
        default 20 if IDF_TARGET_ESP32C2
        default 21 if IDF_TARGET_ESP32C3
        default 16 if IDF_TARGET_ESP32C6
        default 37 if IDF_TARGET_ESP32P4
        default 24 if IDF_TARGET_ESP32H2
        default 43
        help
             This GPIO is used for console UART TX output in the ESP-IDF Bootloader and the app (including
             boot log output and default standard output and standard error of the app).

             If the configuration is different in the Bootloader binary compared to the app binary, UART
             is reconfigured after the bootloader exits and the app starts.

    config ESP_CONSOLE_UART_RX_GPIO
        int "UART RX on GPIO#"
        depends on ESP_CONSOLE_UART_CUSTOM
        range 0 SOC_GPIO_IN_RANGE_MAX
        default 3 if IDF_TARGET_ESP32
        default 19 if IDF_TARGET_ESP32C2
        default 20 if IDF_TARGET_ESP32C3
        default 17 if IDF_TARGET_ESP32C6
        default 38 if IDF_TARGET_ESP32P4
        default 23 if IDF_TARGET_ESP32H2
        default 44
        help
            This GPIO is used for UART RX input in the ESP-IDF Bootloader and the app (including
            default default standard input of the app).

            Note: The default ESP-IDF Bootloader configures this pin but doesn't read anything from the UART.

            If the configuration is different in the Bootloader binary compared to the app binary, UART
            is reconfigured after the bootloader exits and the app starts.


    config ESP_CONSOLE_UART_BAUDRATE
        int
        prompt "UART console baud rate" if ESP_CONSOLE_UART_CUSTOM
        depends on ESP_CONSOLE_UART
        default 74880 if (IDF_TARGET_ESP32C2 && XTAL_FREQ_26)
        default 115200
        range 1200 4000000 if !PM_ENABLE
        range 1200 1000000 if PM_ENABLE
        help
            This baud rate is used by both the ESP-IDF Bootloader and the app (including
            boot log output and default standard input/output/error of the app).

            The app's maximum baud rate depends on the UART clock source. If Power Management is disabled,
            the UART clock source is the APB clock and all baud rates in the available range will be sufficiently
            accurate. If Power Management is enabled, REF_TICK clock source is used so the baud rate is divided
            from 1MHz. Baud rates above 1Mbps are not possible and values between 500Kbps and 1Mbps may not be
            accurate.

            If the configuration is different in the Bootloader binary compared to the app binary, UART
            is reconfigured after the bootloader exits and the app starts.

    config ESP_CONSOLE_USB_CDC_RX_BUF_SIZE
        int "Size of USB CDC RX buffer"
        depends on ESP_CONSOLE_USB_CDC
        default 64
        range 4 16384
        help
            Set the size of USB CDC RX buffer. Increase the buffer size if your application
            is often receiving data over USB CDC.

    config ESP_CONSOLE_USB_CDC_SUPPORT_ETS_PRINTF
        bool "Enable esp_rom_printf / ESP_EARLY_LOG via USB CDC"
        depends on ESP_CONSOLE_USB_CDC
        default n
        help
            If enabled, esp_rom_printf and ESP_EARLY_LOG output will also be sent over USB CDC.
            Disabling this option saves about 1kB or RAM.

    config ESP_INT_WDT
        bool "Interrupt watchdog"
        default y
        help
            This watchdog timer can detect if the FreeRTOS tick interrupt has not been called for a certain time,
            either because a task turned off interrupts and did not turn them on for a long time, or because an
            interrupt handler did not return. It will try to invoke the panic handler first and failing that
            reset the SoC.

    config ESP_INT_WDT_TIMEOUT_MS
        int "Interrupt watchdog timeout (ms)"
        depends on ESP_INT_WDT
        default 300 if !(SPIRAM && IDF_TARGET_ESP32)
        default 800 if (SPIRAM && IDF_TARGET_ESP32)
        range 10 10000
        help
            The timeout of the watchdog, in miliseconds. Make this higher than the FreeRTOS tick rate.

    config ESP_INT_WDT_CHECK_CPU1
        bool "Also watch CPU1 tick interrupt"
        depends on ESP_INT_WDT && !FREERTOS_UNICORE
        default y
        help
            Also detect if interrupts on CPU 1 are disabled for too long.

    config ESP_TASK_WDT_EN
        bool "Enable Task Watchdog Timer"
        default y
        help
            The Task Watchdog Timer can be used to make sure individual tasks are still
            running. Enabling this option will enable the Task Watchdog Timer. It can be
            either initialized automatically at startup or initialized after startup
            (see Task Watchdog Timer API Reference)

    config ESP_TASK_WDT_USE_ESP_TIMER
        # Software implementation of Task Watchdog, handy for targets with only a single
        # Timer Group, such as the ESP32-C2
        bool
        depends on ESP_TASK_WDT_EN
        default y if IDF_TARGET_ESP32C2
        default n if !IDF_TARGET_ESP32C2
        select ESP_TIMER_SUPPORTS_ISR_DISPATCH_METHOD

    config ESP_TASK_WDT_INIT
        bool "Initialize Task Watchdog Timer on startup"
        depends on ESP_TASK_WDT_EN
        default y
        help
            Enabling this option will cause the Task Watchdog Timer to be initialized
            automatically at startup.

    config ESP_TASK_WDT_PANIC
        bool "Invoke panic handler on Task Watchdog timeout"
        depends on ESP_TASK_WDT_INIT
        default n
        help
            If this option is enabled, the Task Watchdog Timer will be configured to
            trigger the panic handler when it times out. This can also be configured
            at run time (see Task Watchdog Timer API Reference)

    config ESP_TASK_WDT_TIMEOUT_S
        int "Task Watchdog timeout period (seconds)"
        depends on ESP_TASK_WDT_INIT
        range 1 60
        default 5
        help
            Timeout period configuration for the Task Watchdog Timer in seconds.
            This is also configurable at run time (see Task Watchdog Timer API Reference)

    config ESP_TASK_WDT_CHECK_IDLE_TASK_CPU0
        bool "Watch CPU0 Idle Task"
        depends on ESP_TASK_WDT_INIT
        default y
        help
            If this option is enabled, the Task Watchdog Timer will watch the CPU0
            Idle Task. Having the Task Watchdog watch the Idle Task allows for detection
            of CPU starvation as the Idle Task not being called is usually a symptom of
            CPU starvation. Starvation of the Idle Task is detrimental as FreeRTOS household
            tasks depend on the Idle Task getting some runtime every now and then.

    config ESP_TASK_WDT_CHECK_IDLE_TASK_CPU1
        bool "Watch CPU1 Idle Task"
        depends on ESP_TASK_WDT_INIT && !FREERTOS_UNICORE
        default y
        help
            If this option is enabled, the Task Watchdog Timer will wach the CPU1
            Idle Task.

    config ESP_XT_WDT
        bool "Initialize XTAL32K watchdog timer on startup"
        depends on !IDF_TARGET_ESP32 && (ESP_SYSTEM_RTC_EXT_OSC || ESP_SYSTEM_RTC_EXT_XTAL)
        default n
        help
            This watchdog timer can detect oscillation failure of the XTAL32K_CLK. When such a failure
            is detected the hardware can be set up to automatically switch to BACKUP32K_CLK and generate
            an interrupt.

    config ESP_XT_WDT_TIMEOUT
        int "XTAL32K watchdog timeout period"
        depends on ESP_XT_WDT
        range 1 255
        default 200
        help
            Timeout period configuration for the XTAL32K watchdog timer based on RTC_CLK.

    config ESP_XT_WDT_BACKUP_CLK_ENABLE
        bool "Automatically switch to BACKUP32K_CLK when timer expires"
        depends on ESP_XT_WDT
        default y
        help
            Enable this to automatically switch to BACKUP32K_CLK as the source of RTC_SLOW_CLK when
            the watchdog timer expires.

    config ESP_PANIC_HANDLER_IRAM
        bool "Place panic handler code in IRAM"
        default n
        help
            If this option is disabled (default), the panic handler code is placed in flash not IRAM.
            This means that if ESP-IDF crashes while flash cache is disabled, the panic handler will
            automatically re-enable flash cache before running GDB Stub or Core Dump. This adds some minor
            risk, if the flash cache status is also corrupted during the crash.

            If this option is enabled, the panic handler code (including required UART functions) is placed
            in IRAM. This may be necessary to debug some complex issues with crashes while flash cache is
            disabled (for example, when writing to SPI flash) or when flash cache is corrupted when an exception
            is triggered.

    config ESP_DEBUG_STUBS_ENABLE
        bool "OpenOCD debug stubs"
        default COMPILER_OPTIMIZATION_LEVEL_DEBUG
        depends on !ESP32_TRAX && !ESP32S2_TRAX && !ESP32S3_TRAX
        help
            Debug stubs are used by OpenOCD to execute pre-compiled onboard code
            which does some useful debugging stuff, e.g. GCOV data dump.

    config ESP_DEBUG_OCDAWARE
        bool "Make exception and panic handlers JTAG/OCD aware"
        default y
        select FREERTOS_DEBUG_OCDAWARE
        help
            The FreeRTOS panic and unhandled exception handers can detect a JTAG OCD debugger and
            instead of panicking, have the debugger stop on the offending instruction.

    choice ESP_SYSTEM_CHECK_INT_LEVEL
        prompt "Interrupt level to use for Interrupt Watchdog and other system checks"
        default ESP_SYSTEM_CHECK_INT_LEVEL_4
        help
            Interrupt level to use for Interrupt Watchdog, IPC_ISR and other system checks.

        config ESP_SYSTEM_CHECK_INT_LEVEL_5
            bool "Level 5 interrupt"
            depends on IDF_TARGET_ESP32
            help
                Using level 5 interrupt for Interrupt Watchdog, IPC_ISR and other system checks.

        config ESP_SYSTEM_CHECK_INT_LEVEL_4
            bool "Level 4 interrupt"
            depends on !BTDM_CTRL_HLI
            help
                Using level 4 interrupt for Interrupt Watchdog, IPC_ISR and other system checks.
    endchoice

    # Insert chip-specific system config
    rsource "./port/soc/$IDF_TARGET/Kconfig.system"

    config ESP_SYSTEM_BROWNOUT_INTR
        bool
        default n
        help
            This config allows to trigger an interrupt when brownout detected. Software restart will be done
            at the end of the default callback.
            Two occasions need to restart the chip with interrupt so far.
            (1). For ESP32 version 1, brown-out reset function doesn't work (see ESP32 errata 3.4).
                  So that we must restart from interrupt.
            (2). For special workflow, the chip needs do more things instead of restarting directly. This part
                 needs to be done in callback function of interrupt.

    config ESP_SYSTEM_HW_STACK_GUARD
        bool "Hardware stack guard"
        depends on SOC_ASSIST_DEBUG_SUPPORTED
        default y
        help
            This config allows to trigger a panic interrupt when Stack Pointer register goes out of allocated stack
            memory bounds.

endmenu  # ESP System Settings

menu "IPC (Inter-Processor Call)"

    config ESP_IPC_TASK_STACK_SIZE
        int "Inter-Processor Call (IPC) task stack size"
        range 512 65536 if !APPTRACE_ENABLE
        range 2048 65536 if APPTRACE_ENABLE
        default 2048 if APPTRACE_ENABLE
        default 1280 if !APPTRACE_ENABLE && IDF_TARGET_ESP32S3
        default 1024
        help
            Configure the IPC tasks stack size. An IPC task runs on each core (in dual core mode), and allows for
            cross-core function calls. See IPC documentation for more details. The default IPC stack size should be
            enough for most common simple use cases. However, users can increase/decrease the stack size to their
            needs.

    config ESP_IPC_USES_CALLERS_PRIORITY
        bool "IPC runs at caller's priority"
        default y
        depends on !FREERTOS_UNICORE
        help
            If this option is not enabled then the IPC task will keep behavior same as prior to that of ESP-IDF v4.0,
            hence IPC task will run at (configMAX_PRIORITIES - 1) priority.

    config ESP_IPC_ISR_ENABLE
        bool
        default y if !FREERTOS_UNICORE
        help
            The IPC ISR feature is similar to the IPC feature except that the callback function is executed in the
            context of a High Priority Interrupt. The IPC ISR feature is intended for low latency execution of simple
            callbacks written in assembly on another CPU. Due to being run in a High Priority Interrupt, the assembly
            callbacks must be written with particular restrictions (see "IPC" and "High-Level Interrupt" docs for more
            details).

endmenu # "IPC (Inter-Processor Call)