Help¶

The kernel may reserve some of the highest interrupts priorities in the system for its own use. These interrupts will not be masked by interrupt locking. When connecting interrupts the kernel will offset all interrupts to lower priority than those reserved by the kernel. Zero-latency interrupt can be used to set up an interrupt at the highest interrupt priority which will not be blocked by interrupt locking. Since Zero-latency ISRs will run in the same priority or possibly at higher priority than the rest of the kernel they cannot use any kernel functionality.

Direct dependencies¶

CPU_CORTEX_M_HAS_BASEPRI && (ARMV6_M_ARMV8_M_BASELINE || ARMV7_M_ARMV8_M_MAINLINE) && CPU_CORTEX_M && !ARM64 && ARM

(Includes any dependencies from ifs and menus.)

Defaults¶

No defaults. Implicitly defaults to n.

Symbols that select this symbol¶

Kconfig definition¶

At <Zephyr>/arch/arm/core/aarch32/cortex_m/Kconfig:246

Included via <Zephyr>/Kconfig:8 → <Zephyr>/Kconfig.zephyr:29 → <Zephyr>/arch/Kconfig:12 → <Zephyr>/arch/arm/Kconfig:42 → <Zephyr>/arch/arm/core/aarch32/Kconfig:237

Menu path: (Top) → ARM Options → ARM Cortex-M0/M0+/M1/M3/M4/M7/M23/M33 options

config ZERO_LATENCY_IRQS
    bool "Enable zero-latency interrupts"
    depends on CPU_CORTEX_M_HAS_BASEPRI && (ARMV6_M_ARMV8_M_BASELINE || ARMV7_M_ARMV8_M_MAINLINE) && CPU_CORTEX_M && !ARM64 && ARM
    help
      The kernel may reserve some of the highest interrupts priorities in
      the system for its own use. These interrupts will not be masked
      by interrupt locking.
      When connecting interrupts the kernel will offset all interrupts
      to lower priority than those reserved by the kernel.
      Zero-latency interrupt can be used to set up an interrupt at the
      highest interrupt priority which will not be blocked by interrupt
      locking.
      Since Zero-latency ISRs will run in the same priority or possibly at
      higher priority than the rest of the kernel they cannot use any
      kernel functionality.

(The ‘depends on’ condition includes propagated dependencies from ifs and menus.)