IRQs

The IRQ and ICU class. More...

Collaboration diagram for IRQs:

Data Structures
class	L4::Irq
	C++ version of an L4 IRQ. More...

Enumerations
enum	L4_irq_flow_type {   L4_IRQ_F_NONE = 0, L4_IRQ_F_LEVEL = 0x2, L4_IRQ_F_EDGE = 0x0, L4_IRQ_F_POS = 0x0,   L4_IRQ_F_NEG = 0x4, L4_IRQ_F_BOTH = 0x8, L4_IRQ_F_LEVEL_HIGH = 0x3, L4_IRQ_F_LEVEL_LOW = 0x7,   L4_IRQ_F_POS_EDGE = 0x1, L4_IRQ_F_NEG_EDGE = 0x5, L4_IRQ_F_BOTH_EDGE = 0x9, L4_IRQ_F_MASK = 0xf }
	Interrupt flow types. More...

Functions
l4_msgtag_t	l4_irq_attach (l4_cap_idx_t irq, l4_umword_t label, l4_cap_idx_t thread) L4_NOTHROW
	Attach to an interrupt source.
l4_msgtag_t	l4_irq_chain (l4_cap_idx_t irq, l4_umword_t label, l4_cap_idx_t slave) L4_NOTHROW
	Chain an IRQ to another master IRQ source.
l4_msgtag_t	l4_irq_detach (l4_cap_idx_t irq) L4_NOTHROW
	Detach from an interrupt source.
l4_msgtag_t	l4_irq_trigger (l4_cap_idx_t irq) L4_NOTHROW
	Trigger an IRQ.
l4_msgtag_t	l4_irq_receive (l4_cap_idx_t irq, l4_timeout_t to) L4_NOTHROW
	Unmask and wait for specified IRQ.
l4_msgtag_t	l4_irq_wait (l4_cap_idx_t irq, l4_umword_t *label, l4_timeout_t to) L4_NOTHROW
	Unmask IRQ and wait for any message.
l4_msgtag_t	l4_irq_unmask (l4_cap_idx_t irq) L4_NOTHROW
	Unmask IRQ.

Detailed Description

The IRQ and ICU class.

#include <l4/sys/irq.h>

The IRQ class provides access to abstract interrupts provided by the micro kernel. Interrupts may be hardware interrupts provided by the platform interrupt controller, virtual device interrupts provided by the micro kernel virtual devices (virtual serial or trace buffer), or IRQs (virtual interrupts that can be triggered by user programs).

IRQ objects can be created using a Factory, see Factory (l4_factory_create_irq()).

Enumeration Type Documentation

enum L4_irq_flow_type

Interrupt flow types.

Enumerator:

L4_IRQ_F_NONE	None.
L4_IRQ_F_LEVEL	Level triggered.
L4_IRQ_F_EDGE	Edge triggered.
L4_IRQ_F_POS	Positive trigger.
L4_IRQ_F_NEG	Negative trigger.
L4_IRQ_F_BOTH	Both edges trigger.
L4_IRQ_F_LEVEL_HIGH	Level high trigger.
L4_IRQ_F_LEVEL_LOW	Level low trigger.
L4_IRQ_F_POS_EDGE	Positive edge trigger.
L4_IRQ_F_NEG_EDGE	Negative edge trigger.
L4_IRQ_F_BOTH_EDGE	Both edges trigger.
L4_IRQ_F_MASK	Mask.

Definition at line 61 of file icu.h.

Function Documentation

l4_msgtag_t l4_irq_attach ( l4_cap_idx_t  irq, l4_umword_t  label, l4_cap_idx_t  thread  )

inline

Attach to an interrupt source.

Parameters

irq	IRQ to attach to.
label	Identifier of the IRQ.
thread	Thread to attach the interrupt to.

Returns

Syscall return tag

Examples:

examples/sys/isr/main.c.

Definition at line 281 of file irq.h.

References l4_utcb().

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l4_msgtag_t l4_irq_chain ( l4_cap_idx_t  irq, l4_umword_t  label, l4_cap_idx_t  slave  )

inline

Chain an IRQ to another master IRQ source.

The chaining feature of IRQ objects allows to deal with shared IRQs. For chaining IRQs there must be a master IRQ object, bound to the real IRQ source. Note, the master IRQ must not have a thread attached to it. This function allows to add a limited number of slave IRQs to this master IRQ, with the semantics that each of the slave IRQs is triggered whenever the master IRQ is triggered. The master IRQ will be masked automatically when an IRQ is delivered and shall be unmasked when all attached slave IRQs are unmasked.

Parameters

irq	The master IRQ object.
label	Identifier of the IRQ.
slave	The slave that shall be attached to the master.

Returns

Syscall return tag

Definition at line 288 of file irq.h.

References l4_utcb().

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l4_msgtag_t l4_irq_detach ( l4_cap_idx_t  irq )

inline

Detach from an interrupt source.

Parameters

irq	IRQ to detach from.

Returns

Syscall return tag

Examples:

examples/sys/isr/main.c.

Definition at line 295 of file irq.h.

References l4_utcb().

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l4_msgtag_t l4_irq_trigger ( l4_cap_idx_t  irq )

inline

Trigger an IRQ.

Parameters

irq	IRQ to trigger.

Precondition

irq must be a reference to an IRQ.

Returns

Syscall return tag.

Note that this function is a send only operation, i.e. there is no return value except for a failed send operation. Especially l4_error() will return an error value from the message tag which still contains the IRQ protocol used for the send operation.

Use l4_ipc_error() to check for (send) errors.

Definition at line 301 of file irq.h.

References l4_utcb().

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l4_msgtag_t l4_irq_receive ( l4_cap_idx_t  irq, l4_timeout_t  to  )

inline

Unmask and wait for specified IRQ.

Parameters

irq	IRQ to wait for.
to	Timeout.

Returns

Syscall return tag

Examples:

examples/sys/isr/main.c.

Definition at line 307 of file irq.h.

References l4_utcb().

Referenced by L4Re::Util::Event_buffer_consumer_t< PAYLOAD >::process().

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l4_msgtag_t l4_irq_wait ( l4_cap_idx_t  irq, l4_umword_t *  label, l4_timeout_t  to  )

inline

Unmask IRQ and wait for any message.

Parameters

irq	IRQ to wait for.
label	Receive label.
to	Timeout.

Returns

Syscall return tag

Definition at line 313 of file irq.h.

References l4_utcb().

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l4_msgtag_t l4_irq_unmask ( l4_cap_idx_t  irq )

inline

Unmask IRQ.

Parameters

irq	IRQ to unmask.

Returns

Syscall return tag

Note

l4_irq_wait and l4_irq_receive are doing the unmask themselves.

Definition at line 320 of file irq.h.

References l4_utcb().

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