kernel.h File Reference

Furi Kernel primitives. More...

#include <core/base.h>

Go to the source code of this file.

Functions
bool	furi_kernel_is_irq_or_masked (void)
	Check if CPU is in IRQ or kernel running and IRQ is masked.
bool	furi_kernel_is_running (void)
	Check if kernel is running.
int32_t	furi_kernel_lock (void)
	Lock kernel, pause process scheduling.
int32_t	furi_kernel_unlock (void)
	Unlock kernel, resume process scheduling.
int32_t	furi_kernel_restore_lock (int32_t lock)
	Restore kernel lock state.
uint32_t	furi_kernel_get_tick_frequency (void)
	Get kernel systick frequency.
void	furi_delay_tick (uint32_t ticks)
	Delay execution.
FuriStatus	furi_delay_until_tick (uint32_t tick)
	Delay until tick.
uint32_t	furi_get_tick (void)
	Get current tick counter.
uint32_t	furi_ms_to_ticks (uint32_t milliseconds)
	Convert milliseconds to ticks.
void	furi_delay_ms (uint32_t milliseconds)
	Delay in milliseconds.
void	furi_delay_us (uint32_t microseconds)
	Delay in microseconds.

Detailed Description

Furi Kernel primitives.

Function Documentation

furi_delay_ms()

void furi_delay_ms

(

uint32_t

milliseconds

)

Delay in milliseconds.

This method uses kernel ticks on the inside, which causes delay to be aliased to scheduler timer intervals. Real wait time will be between X+ milliseconds. Special value: 0, will cause task yield. Also if used when kernel is not running will fall back to furi_delay_us.

Warning

Cannot be used from ISR

Parameters

[in]

milliseconds

milliseconds to wait

furi_delay_tick()

void furi_delay_tick

(

uint32_t

ticks

)

Delay execution.

Warning

This should never be called in interrupt request context.

Also keep in mind delay is aliased to scheduler timer intervals.

Parameters

[in]

ticks

The ticks count to pause

furi_delay_until_tick()

FuriStatus furi_delay_until_tick

(

uint32_t

tick

)

Delay until tick.

Warning

This should never be called in interrupt request context.

Parameters

[in]

tick

The tick until which kernel should delay task execution

Returns

The furi status.

furi_delay_us()

void furi_delay_us

(

uint32_t

microseconds

)

Delay in microseconds.

Implemented using Cortex DWT counter. Blocking and non aliased.

Parameters

[in]

microseconds

microseconds to wait

furi_get_tick()

uint32_t furi_get_tick

(

void

)

Get current tick counter.

System uptime, may overflow.

Returns

Current ticks in milliseconds

furi_kernel_get_tick_frequency()

uint32_t furi_kernel_get_tick_frequency

(

void

)

Get kernel systick frequency.

Returns

systick counts per second

furi_kernel_is_irq_or_masked()

bool furi_kernel_is_irq_or_masked

(

void

)

Check if CPU is in IRQ or kernel running and IRQ is masked.

Originally this primitive was born as a workaround for FreeRTOS kernel primitives shenanigans with PRIMASK.

Meaningful use cases are:

• When kernel is started and you want to ensure that you are not in IRQ or IRQ is not masked(like in critical section)
• When kernel is not started and you want to make sure that you are not in IRQ mode, ignoring PRIMASK.

As you can see there will be edge case when kernel is not started and PRIMASK is not 0 that may cause some funky behavior. Most likely it will happen after kernel primitives being used, but control not yet passed to kernel. It's up to you to figure out if it is safe for your code or not.

Returns

true if CPU is in IRQ or kernel running and IRQ is masked

furi_kernel_is_running()

bool furi_kernel_is_running

(

void

)

Check if kernel is running.

Returns

true if running, false otherwise

furi_kernel_lock()

int32_t furi_kernel_lock

(

void

)

Lock kernel, pause process scheduling.

Warning

This should never be called in interrupt request context.

Returns

previous lock state(0 - unlocked, 1 - locked)

furi_kernel_restore_lock()

int32_t furi_kernel_restore_lock

(

int32_t

lock

)

Restore kernel lock state.

Warning

This should never be called in interrupt request context.

Parameters

[in]

lock

The lock state

Returns

new lock state or error

furi_kernel_unlock()

int32_t furi_kernel_unlock

(

void

)

Unlock kernel, resume process scheduling.

Warning

This should never be called in interrupt request context.

Returns

previous lock state(0 - unlocked, 1 - locked)

furi_ms_to_ticks()

uint32_t furi_ms_to_ticks

(

uint32_t

milliseconds

)

Convert milliseconds to ticks.

Parameters

[in]

milliseconds

time in milliseconds

Returns

time in ticks