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Elixir Cross Referencer

# Timer driver configuration options

# 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

menu "Timer Drivers"

menuconfig APIC_TIMER
	bool "New local APIC timer"
	depends on X86
	depends on LOAPIC
	select TICKLESS_CAPABLE
	help
	  Use the x86 local APIC as the system time source.

if APIC_TIMER

config APIC_TIMER_IRQ
	int "Local APIC timer IRQ"
	default 24
	help
	  This option specifies the IRQ used by the local APIC timer.

config APIC_TIMER_IRQ_PRIORITY
	int "Local APIC timer IRQ priority"
	default 4
	help
	  This option specifies the IRQ priority used by the local APIC timer.

config APIC_TIMER_TSC
	bool "Use invariant TSC for z_timer_cycle_get_32()"
	help
	  If your CPU supports invariant TSC, and you know the ratio of the
	  TSC frequency to CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC (the local APIC
	  timer frequency), then enable this for a much faster and more
	  accurate z_timer_cycle_get_32().

if APIC_TIMER_TSC

config APIC_TIMER_TSC_N
	int "TSC to local APIC timer frequency multiplier (N)"
	default 1

config APIC_TIMER_TSC_M
	int "TSC to local APIC timer frequency divisor (M)"
	default 1

endif # APIC_TIMER_TSC

endif # APIC_TIMER

config HPET_TIMER
	bool "HPET timer"
	depends on X86
	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.

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 ARM_ARCH_TIMER
	bool "ARM architected timer"
	depends on GIC
	select TICKLESS_CAPABLE
	help
	  This module implements a kernel device driver for the ARM architected
	  timer which provides per-cpu timers attached to a GIC to deliver its
	  per-processor interrupts via PPIs.

DT_COMPAT_ARM_V6M_SYSTICK := arm,armv6m-systick
DT_COMPAT_ARM_V7M_SYSTICK := arm,armv7m-systick
DT_COMPAT_ARM_V8M_SYSTICK := arm,armv8m-systick

config CORTEX_M_SYSTICK
	bool "Cortex-M SYSTICK timer"
	depends on CPU_CORTEX_M_HAS_SYSTICK
	default $(dt_compat_enabled,$(DT_COMPAT_ARM_V6M_SYSTICK)) || \
		$(dt_compat_enabled,$(DT_COMPAT_ARM_V7M_SYSTICK)) || \
		$(dt_compat_enabled,$(DT_COMPAT_ARM_V8M_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 ITE_IT8XXX2_TIMER
	bool "ITE it8xxx2 timer driver"
	depends on SOC_IT8XXX2
	select TICKLESS_CAPABLE
	help
	  This module implements a kernel device driver for the ITE it8xxx2
	  HW timer model

config NRF_RTC_TIMER
	bool "nRF Real Time Counter (NRF_RTC1) Timer"
	depends on CLOCK_CONTROL
	depends on SOC_COMPATIBLE_NRF
	select TICKLESS_CAPABLE
	select NRF_HW_RTC1_RESERVED
	help
	  This module implements a kernel device driver for the nRF Real Time
	  Counter NRF_RTC1 and provides the standard "system clock driver"
	  interfaces.

if NRF_RTC_TIMER

config NRF_RTC_TIMER_USER_CHAN_COUNT
	int "Additional channels that can be used"
	default 0
	help
	  Use nrf_rtc_timer.h API. Driver is not managing allocation of channels.

choice
	prompt "Clock startup policy"
	default SYSTEM_CLOCK_WAIT_FOR_STABILITY

config SYSTEM_CLOCK_NO_WAIT
	bool "No wait"
	help
	  System clock source is initiated but does not wait for clock readiness.
	  When this option is picked, system clock may not be ready when code relying
	  on kernel API is executed. Requested timeouts will be prolonged by the
	  remaining startup time.

config SYSTEM_CLOCK_WAIT_FOR_AVAILABILITY
	bool "Wait for availability"
	help
	  System clock source initialization waits until clock is available. In some
	  systems, clock initially runs from less accurate source which has faster
	  startup time and then seamlessly switches to the target clock source when
	  it is ready. When this option is picked, system clock is available after
	  system clock driver initialization but it may be less accurate. Option is
	  equivalent to waiting for stability if clock source does not have
	  intermediate state.

config SYSTEM_CLOCK_WAIT_FOR_STABILITY
	bool "Wait for stability"
	help
	  System clock source initialization waits until clock is stable. When this
	  option is picked, system clock is available and stable after system clock
	  driver initialization.

endchoice

endif # NRF_RTC_TIMER

source "drivers/timer/Kconfig.stm32_lptim"

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 LITEX_TIMER
	bool "LiteX Timer"
	default y
	depends on !TICKLESS_IDLE
	depends on SOC_RISCV32_LITEX_VEXRISCV
	help
	  This module implements a kernel device driver for LiteX Timer.

config NATIVE_POSIX_TIMER
	bool "(POSIX) native_posix timer driver"
	default y
	depends on BOARD_NATIVE_POSIX
	select TICKLESS_CAPABLE
	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 MCHP_XEC_RTOS_TIMER
	bool "Microchip XEC series RTOS timer"
	depends on SOC_FAMILY_MEC
	select TICKLESS_CAPABLE
	help
	  This module implements a kernel device driver for the Microchip
	  XEC series RTOS timer and provides the standard "system clock
	  driver" interfaces.

config CC13X2_CC26X2_RTC_TIMER
	bool "TI SimpleLink CC13x2/CC26x2 RTC timer"
	depends on SOC_SERIES_CC13X2_CC26X2
	select TICKLESS_CAPABLE
	help
	  This module implements a kernel device driver for the TI SimpleLink
	  CC13X2_CC26X2 series Real Time Counter and provides the standard
	  "system clock driver" interfaces.

config XLNX_PSTTC_TIMER
	bool "Xilinx PS ttc timer support"
	default y
	depends on SOC_XILINX_ZYNQMP
	select TICKLESS_CAPABLE
	help
	  This module implements a kernel device driver for the Xilinx ZynqMP
	  platform provides the standard "system clock driver" interfaces.
	  If unchecked, no timer will be used.

config XLNX_PSTTC_TIMER_INDEX
	int "Xilinx PS ttc timer index"
	range 0 3
	default 0
	depends on XLNX_PSTTC_TIMER
	help
	  This is the index of TTC timer picked to provide system clock.

config CAVS_TIMER
	bool "CAVS DSP Wall Clock Timer on Intel SoC"
	depends on CAVS_ICTL
	select TICKLESS_CAPABLE
	help
	  The DSP wall clock timer is a timer driven directly by
	  external oscillator and is external to the CPU core(s).
	  It is not as fast as the internal core clock, but provides
	  a common and synchronized counter for all CPU cores (which
	  is useful for SMP).

config LEON_GPTIMER
	bool "LEON timer"
	depends on SOC_SPARC_LEON
	select DYNAMIC_INTERRUPTS
	help
	  This module implements a kernel device driver for the GRLIB
	  GPTIMER which is common in LEON systems.

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_SLOPPY_IDLE
	bool "Timer allowed to skew uptime clock during idle"
	help
	  When true, the timer driver is not required to maintain a
	  correct system uptime count when the system enters idle.
	  Some platforms may take advantage of this to reduce the
	  overhead from regular interrupts required to handle counter
	  wraparound conditions.

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).

# Hidden option to be selected by individual SoC.
config TICKLESS_CAPABLE
	bool
	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.

endmenu