zephyr/drivers/timer/Kconfig.cortex_m_systick

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# Copyright (c) 2014-2015 Wind River Systems, Inc.
# Copyright (c) 2016 Cadence Design Systems, Inc.
# Copyright (c) 2019 Intel Corp.
# SPDX-License-Identifier: Apache-2.0
config CORTEX_M_SYSTICK
bool "Cortex-M SYSTICK timer"
depends on CPU_CORTEX_M_HAS_SYSTICK
default y
depends on DT_HAS_ARM_ARMV6M_SYSTICK_ENABLED || \
DT_HAS_ARM_ARMV7M_SYSTICK_ENABLED || \
DT_HAS_ARM_ARMV8M_SYSTICK_ENABLED || \
DT_HAS_ARM_ARMV8_1M_SYSTICK_ENABLED
select TICKLESS_CAPABLE
select SYSTEM_TIMER_HAS_DISABLE_SUPPORT
select CORTEX_M_SYSTICK_INSTALL_ISR
help
This module implements a kernel device driver for the Cortex-M processor
SYSTICK timer and provides the standard "system clock driver" interfaces.
config CORTEX_M_SYSTICK_INSTALL_ISR
bool
depends on CPU_CORTEX_M_HAS_SYSTICK
help
This option should be selected by SysTick-based drivers so that the
sys_clock_isr() function is installed.
config CORTEX_M_SYSTICK_64BIT_CYCLE_COUNTER
bool "Cortex-M SYSTICK timer with sys_clock_cycle_get_64() support"
depends on CORTEX_M_SYSTICK
default y if (SYS_CLOCK_HW_CYCLES_PER_SEC > 60000000)
select TIMER_HAS_64BIT_CYCLE_COUNTER
help
This driver, due to its limited 24-bits hardware counter, is already
tracking a separate cycle count in software. This option make that
count a 64-bits value to support sys_clock_cycle_get_64().
This is cheap to do as expensive math operations (i.e. divisions)
are performed only on counter interval values that always fit in
32 bits.
This is set to y by default when the hardware clock is fast enough
to wrap sys_clock_cycle_get_32() in about a minute or less.