Concrete implementation of IPlatform driver for the Arm Cortex-M0, M3, M4, M7 processors. More...

#include <stk_arch_arm-cortex-m.h>

Inheritance diagram for stk::PlatformArmCortexM:

Collaboration diagram for stk::PlatformArmCortexM:

Public Member Functions
	~PlatformArmCortexM ()=default
	Destructor.
void	Initialize (IEventHandler event_handler, IKernelService service, uint32_t resolution_us, Stack *exit_trap) override
	Initialize scheduler's context.
void	Start () override
	Start scheduling.
void	Stop () override
	Stop scheduling.
void	InitStack (EStackType stack_type, Stack stack, IStackMemory stack_memory, ITask *user_task) override
	Initialize stack memory of the user task.
uint32_t	GetTickResolution () const override
	Get resolution of the system tick timer in microseconds. Resolution means a number of microseconds between system tick timer ISRs.
Cycles	GetSysTimerCount () const override
	Get system timer count value.
uint32_t	GetSysTimerFrequency () const override
	Get system timer frequency.
void	SwitchToNext () override
	Switch to a next task.
void	Sleep (Timeout ticks) override
	Put calling process into a sleep state.
bool	SleepUntil (Ticks timestamp) override
	Put calling process into a sleep state until the specified timestamp.
IWaitObject *	Wait (ISyncObject sync_obj, IMutex mutex, Timeout timeout) override
	Put calling process into a waiting state until synchronization object is signaled or timeout occurs.
void	ProcessTick () override
	Process one tick.
void	ProcessHardFault () override
	Cause a hard fault of the system.
void	SetEventOverrider (IEventOverrider *overrider) override
	Set platform event overrider.
Word	GetCallerSP () const override
	Get caller's Stack Pointer (SP).
TId	GetTid () const override
	Get thread Id.
Timeout	Suspend () override
	Suspend scheduling.
void	Resume (Timeout elapsed_ticks) override
	Resume scheduling after a prior Suspend() call.

Detailed Description

Concrete implementation of IPlatform driver for the Arm Cortex-M0, M3, M4, M7 processors.

Definition at line 24 of file stk_arch_arm-cortex-m.h.

Constructor & Destructor Documentation

◆ ~PlatformArmCortexM()

stk::PlatformArmCortexM::~PlatformArmCortexM ( )

default

Destructor.

Note: MISRA deviation: [STK-DEV-005] Rule 10-3-2.

References STK_VIRT_DTOR.

Member Function Documentation

◆ GetCallerSP()

Word stk::PlatformArmCortexM::GetCallerSP ( ) const

overridevirtual

Get caller's Stack Pointer (SP).

Note: Valid for a Thread process only.

Returns: Current value of the Stack Pointer (SP) of the calling process.

Implements stk::IPlatform.

◆ GetSysTimerCount()

Cycles stk::PlatformArmCortexM::GetSysTimerCount ( ) const

overridevirtual

Get system timer count value.

Note: ISR-safe.

Returns: 64-bit count value.

Implements stk::IPlatform.

◆ GetSysTimerFrequency()

uint32_t stk::PlatformArmCortexM::GetSysTimerFrequency ( ) const

overridevirtual

Get system timer frequency.

Note: ISR-safe.

Returns: Frequency (Hz).

Implements stk::IPlatform.

◆ GetTickResolution()

uint32_t stk::PlatformArmCortexM::GetTickResolution ( ) const

overridevirtual

Get resolution of the system tick timer in microseconds. Resolution means a number of microseconds between system tick timer ISRs.

Returns: Microseconds.

Implements stk::IPlatform.

◆ GetTid()

TId stk::PlatformArmCortexM::GetTid ( ) const

overridevirtual

Get thread Id.

Returns: Thread Id.

Warning: ISR-safe.

See also: TID_ISR_N, TID_NONE, IsIsrTid

Implements stk::IPlatform.

◆ Initialize()

void stk::PlatformArmCortexM::Initialize	(	IEventHandler *	event_handler,
		IKernelService *	service,
		uint32_t	resolution_us,
		Stack *	exit_trap )

overridevirtual

Initialize scheduler's context.

Parameters

[in]	event_handler	Event handler.
[in]	service	Kernel service.
[in]	resolution_us	Tick resolution in microseconds (for example 1000 equals to 1 millisecond resolution).
[in]	exit_trap	Stack of the Exit trap (optional, provided if kernel is operating in KERNEL_DYNAMIC mode).

Note: Must be called once before Start().

Implements stk::IPlatform.

◆ InitStack()

void stk::PlatformArmCortexM::InitStack	(	EStackType	stack_type,
		Stack *	stack,
		IStackMemory *	stack_memory,
		ITask *	user_task )

overridevirtual

Initialize stack memory of the user task.

Parameters

[in]	stack_type	Stack type.
[in]	stack	Stack descriptor.
[in]	stack_memory	Stack memory.
[in]	user_task	User task to which Stack belongs.

Implements stk::IPlatform.

◆ ProcessHardFault()

void stk::PlatformArmCortexM::ProcessHardFault ( )

overridevirtual

Cause a hard fault of the system.

Note: Normally called by the Kernel when one of the scheduled tasks missed its deadline (see stk::KERNEL_HRT).

Implements stk::IPlatform.

◆ ProcessTick()

void stk::PlatformArmCortexM::ProcessTick ( )

overridevirtual

Process one tick.

Note: Normally system tick is processed by the platform driver implementation. In case system tick handler is used by the application and should not be implemented by the driver then disable driver's handler in stk_config.h like this:
#define STK_SYSTICK_HANDLER _STK_SYSTICK_HANDLER_DISABLE

and then call ProcessTick() from your custom tick handler.

Implements stk::IPlatform.

◆ Resume()

void stk::PlatformArmCortexM::Resume ( Timeout elapsed_ticks )

overridevirtual

Resume scheduling after a prior Suspend() call.

Parameters

[in] elapsed_ticks Number of ticks that elapsed during the suspended period. The kernel uses this value to advance internal time counters.

Note: ISR-safe.

Implements stk::IPlatform.

◆ SetEventOverrider()

void stk::PlatformArmCortexM::SetEventOverrider ( IEventOverrider * overrider )

overridevirtual

Set platform event overrider.

Note: Must be set prior call to IKernel::Start.

Parameters

[in] overrider Platform event overrider.

Implements stk::IPlatform.

◆ Sleep()

void stk::PlatformArmCortexM::Sleep ( Timeout ticks )

overridevirtual

Put calling process into a sleep state.

Note: Unlike Delay this function does not waste CPU cycles and allows kernel to put CPU into a low-power state.

Parameters

[in] ticks Time to sleep (ticks).

Implements stk::IPlatform.

◆ SleepUntil()

bool stk::PlatformArmCortexM::SleepUntil ( Ticks timestamp )

overridevirtual

Put calling process into a sleep state until the specified timestamp.

Note: Unlike Delay this function does not waste CPU cycles and allows kernel to put CPU into a low-power state.; Unsupported in HRT mode (see stk::KERNEL_HRT); in HRT mode tasks sleep automatically according to their periodicity and workload.

Parameters

[in] timestamp Absolute timestamp (ticks).

Warning: ISR-unsafe. Calling from an ISR context is not permitted and will trigger an assertion.

Returns: True if sleep succeeded, false otherwise.

Implements stk::IPlatform.

◆ Start()

void stk::PlatformArmCortexM::Start ( )

overridevirtual

Start scheduling.

Note: This function never returns if kernel is initialized as KERNEL_STATIC. Must be called after Initialize().

Implements stk::IPlatform.

◆ Stop()

void stk::PlatformArmCortexM::Stop ( )

overridevirtual

Stop scheduling.

Implements stk::IPlatform.

◆ Suspend()

Timeout stk::PlatformArmCortexM::Suspend ( )

overridevirtual

Suspend scheduling.

Returns: Number of ticks available for the suspension period, as determined by the nearest pending wake-up. The caller may use this value to program a hardware timer for the tickless sleep interval.

Note: ISR-safe. Pair with Resume().

Implements stk::IPlatform.

◆ SwitchToNext()

void stk::PlatformArmCortexM::SwitchToNext ( )

overridevirtual

Switch to a next task.

Implements stk::IPlatform.

◆ Wait()

IWaitObject * stk::PlatformArmCortexM::Wait	(	ISyncObject *	sobj,
		IMutex *	mutex,
		Timeout	timeout )

overridevirtual

Put calling process into a waiting state until synchronization object is signaled or timeout occurs.

Note: This function implements core blocking logic using the Monitor pattern to ensure atomicity between state check and suspension.; The kernel automatically unlocks the provided mutex before the task is suspended and re-locks it before this function returns.

Parameters

[in]	sobj	Synchronization object to wait on.
[in]	mutex	Mutex protecting the state of the synchronization object.
[in]	timeout	Maximum wait time (ticks). Use `WAIT_INFINITE` to block indefinitely, use `NO_WAIT` to poll without blocking.

Returns: Pointer to the wait object representing this wait operation (always non-NULL). The caller must check IWaitObject::IsTimeout() after this function returns to determine whether the wake was caused by a signal or by timeout expiry. The returned pointer is valid until the calling task re-enters a wait or the wait object is explicitly released by the kernel. The return value is guaranteed non nullptr and points to a valid IWaitObject.

Warning: ISR-unsafe.

Implements stk::IPlatform.

The documentation for this class was generated from the following file:

stk_arch_arm-cortex-m.h

Public Member Functions

Detailed Description

Constructor & Destructor Documentation

◆ ~PlatformArmCortexM()

Member Function Documentation

◆ GetCallerSP()

◆ GetSysTimerCount()

◆ GetSysTimerFrequency()

◆ GetTickResolution()

◆ GetTid()

◆ Initialize()

◆ InitStack()

◆ ProcessHardFault()

◆ ProcessTick()

◆ Resume()

◆ SetEventOverrider()

◆ Sleep()

◆ SleepUntil()

◆ Start()

◆ Stop()

◆ Suspend()

◆ SwitchToNext()

◆ Wait()