zephyr/drivers/timer/Kconfig

# Kconfig - timer driver configuration options

#
# Copyright (c) 2014-2015 Wind River Systems, Inc.
# Copyright (c) 2016 Cadence Design Systems, Inc.
#
# SPDX-License-Identifier: Apache-2.0
#


menu "Timer Drivers"

menuconfig HPET_TIMER
	bool "HPET timer"
	depends on (X86 || X86_64)
	select IOAPIC if X86
	select LOAPIC if X86
	select TIMER_READS_ITS_FREQUENCY_AT_RUNTIME
	select TICKLESS_CAPABLE
	help
	  This option selects High Precision Event Timer (HPET) as a
	  system timer.

if HPET_TIMER
config HPET_TIMER_BASE_ADDRESS
	hex "HPET Base Address"
	default 0xFED00000
	help
	  This options specifies the base address of the HPET timer device.

config HPET_TIMER_IRQ
	int "HPET Timer IRQ"
	default 2
	help
	  This option specifies the IRQ used by the HPET timer.

config HPET_TIMER_IRQ_PRIORITY
	int "HPET Timer IRQ Priority"
	default 4
	help
	  This option specifies the IRQ priority used by the HPET timer.

endif #HPET_TIMER

menuconfig LOAPIC_TIMER
	bool "LOAPIC timer"
	depends on (LOAPIC || MVIC) && X86
	help
	  This option selects LOAPIC timer as a system timer.

if LOAPIC_TIMER
config LOAPIC_TIMER_IRQ
	int "Local APIC Timer IRQ"
	default 24
	help
	  This option specifies the IRQ used by the LOAPIC timer.

config LOAPIC_TIMER_IRQ_PRIORITY
	int "Local APIC Timer IRQ Priority"
	default 2
	help
	  This options specifies the IRQ priority used by the LOAPIC timer.

config TSC_CYCLES_PER_SEC
	int "Frequency of x86 CPU timestamp counter"
	default 0
	help
	  The x86 implementation of LOAPIC k_cycle_get_32() relies on the x86 TSC.
	  This runs at the CPU speed and not the bus speed. If set to 0, the
	  value of CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC will be used instead;
	  many MCUs these values are the same.

endif #LOAPIC_TIMER

menuconfig ARCV2_TIMER
	bool "ARC Timer"
	default y
	depends on ARC
	select TICKLESS_CAPABLE
	help
	  This module implements a kernel device driver for the ARCv2 processor timer 0
	  and provides the standard "system clock driver" interfaces.

config ARCV2_TIMER_IRQ_PRIORITY
	int "ARC timer interrupt priority"
	default 0
	depends on ARCV2_TIMER
	help
	  This option specifies the IRQ priority used by the ARC timer. Lower
	  values have higher priority.

config CORTEX_M_SYSTICK
	bool "Cortex-M SYSTICK timer"
	depends on CPU_CORTEX_M_HAS_SYSTICK
	select TICKLESS_CAPABLE
	help
	  This module implements a kernel device driver for the Cortex-M processor
	  SYSTICK timer and provides the standard "system clock driver" interfaces.

config ALTERA_AVALON_TIMER
	bool "Altera Avalon Interval Timer"
	default y
	depends on NIOS2
	help
	  This module implements a kernel device driver for the Altera Avalon
	  Interval Timer as described in the Embedded IP documentation, for use
	  with Nios II and possibly other Altera soft CPUs. It provides the
	  standard "system clock driver" interfaces.

config NRF_RTC_TIMER
	bool "nRF Real Time Counter (NRF_RTC1) Timer"
	depends on CLOCK_CONTROL
	depends on SOC_COMPATIBLE_NRF
	select TICKLESS_CAPABLE
	help
	  This module implements a kernel device driver for the nRF Real Time
	  Counter NRF_RTC1 and provides the standard "system clock driver"
	  interfaces.

config RISCV_MACHINE_TIMER
	bool "RISCV Machine Timer"
	depends on SOC_FAMILY_RISCV_PRIVILEGE
	select TICKLESS_CAPABLE
	help
	  This module implements a kernel device driver for the generic RISCV machine
	  timer driver. It provides the standard "system clock driver" interfaces.

config RV32M1_LPTMR_TIMER
	bool "RV32M1 LPTMR system timer driver"
	default y
	depends on SOC_OPENISA_RV32M1_RISCV32
	depends on !TICKLESS_IDLE
	depends on RV32M1_INTMUX
	help
	  This module implements a kernel device driver for using the LPTMR
	  peripheral as the system clock. It provides the standard "system clock
	  driver" interfaces.

config NATIVE_POSIX_TIMER
	bool "(POSIX) native_posix timer driver"
	default y
	depends on BOARD_NATIVE_POSIX
	help
	  This module implements a kernel device driver for the native_posix HW timer
	  model

config XTENSA_TIMER
	bool "Xtensa timer support"
	depends on XTENSA
	default y
	select TICKLESS_CAPABLE
	help
	  Enables a system timer driver for Xtensa based on the CCOUNT
	  and CCOMPARE special registers.

config XTENSA_TIMER_ID
	int "System timer CCOMPAREn register index"
	default 1
	depends on XTENSA_TIMER
	help
	  Index of the CCOMPARE register (and associated interrupt)
	  used for the system timer.  Xtensa CPUs have hard-configured
	  interrupt priorities associated with each timer, and some of
	  them can be unmaskable (and thus not usable by OS code that
	  need synchronization, like the timer subsystem!).  Choose
	  carefully.  Generally you want the timer with the highest
	  priority maskable interrupt.

config SAM0_RTC_TIMER
	bool "Atmel SAM0 series RTC timer"
	depends on SOC_FAMILY_SAM0
	select TICKLESS_CAPABLE
	help
	  This module implements a kernel device driver for the Atmel SAM0
	  series Real Time Counter and provides the standard "system clock
	  driver" interfaces.

config SYSTEM_CLOCK_DISABLE
	bool "API to disable system clock"
	help
	  This option enables the sys_clock_disable() API in the kernel. It is
	  needed by some subsystems (which will automatically select it), but is
	  rarely needed by applications.

config TIMER_READS_ITS_FREQUENCY_AT_RUNTIME
	bool "Timer queries its hardware to find its frequency at runtime"
	help
	  The drivers select this option automatically when needed. Do not modify
	  this unless you have a very good reason for it.

config SYSTEM_CLOCK_INIT_PRIORITY
	int "System clock driver initialization priority"
	default 0
	help
	  This options can be used to set a specific initialization priority
	  value for the system clock driver. As driver initialization  might need
	  the clock to be running already, you should let the default value as it
	  is (0).

config TICKLESS_CAPABLE
	bool "Timer driver supports tickless operation"
	help
	  Timer drivers should select this flag if they are capable of
	  supporting tickless operation.  That is, a call to
	  z_clock_set_timeout() with a number of ticks greater than
	  one should be expected not to produce a call to
	  z_clock_announce() (really, not to produce an interrupt at
	  all) until the specified expiration.

config QEMU_TICKLESS_WORKAROUND
	bool "Disable tickless on qemu due to asynchrony bug"
	depends on QEMU_TARGET && TICKLESS_KERNEL
	help
	  Qemu (without -icount) has trouble keeping time when the
	  host process needs to timeshare.  The host OS will routinely
	  schedule out a process at timescales equivalent to the guest
	  tick rate.  With traditional ticks delivered regularly by
	  the hardware, that's mostly OK as it looks like a late
	  interrupt.  But in tickless mode, the driver needs some CPU
	  in order to schedule the tick in the first place.  If that
	  gets delayed across a tick boundary, time gets wonky.  This
	  tunable is a hint to the driver to disable tickless
	  accounting on qemu.  Use it only on tests that are known to
	  have problems.

endmenu