zircon/vdso/interrupt.fidl

// Copyright 2019 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
library zx;

@transport("Syscall")
closed protocol Interrupt {
    /// ## Summary
    ///
    /// Create an interrupt object.
    ///
    /// ## Declaration
    ///
    /// ```c
    /// #include <zircon/syscalls.h>
    ///
    /// zx_status_t zx_interrupt_create(zx_handle_t src_obj,
    ///                                 uint32_t src_num,
    ///                                 uint32_t options,
    ///                                 zx_handle_t* out_handle);
    /// ```
    ///
    /// ## Description
    ///
    /// `zx_interrupt_create()` creates an interrupt object that represents a physical
    /// or virtual interrupt.
    ///
    /// If *options* is `ZX_INTERRUPT_VIRTUAL`, *src_obj* and *src_num* are ignored and
    /// a virtual interrupt is returned.
    ///
    /// Otherwise *src_obj* must be a suitable resource for creating platform interrupts
    /// or a PCI object, and *src_num* is the associated interrupt number.  This restricts
    /// the creation of interrupts to the internals of the DDK (driver development kit).
    /// Physical interrupts are obtained by drivers through various DDK APIs.
    ///
    /// Physical interrupts honor the options `ZX_INTERRUPT_EDGE_LOW`, `ZX_INTERRUPT_EDGE_HIGH`,
    /// `ZX_INTERRUPT_LEVEL_LOW`, `ZX_INTERRUPT_LEVEL_HIGH`, and `ZX_INTERRUPT_REMAP_IRQ`.
    ///
    /// The handles will have `ZX_RIGHT_INSPECT`, `ZX_RIGHT_DUPLICATE`, `ZX_RIGHT_TRANSFER`
    /// (allowing them to be sent to another process via [`zx_channel_write()`]), `ZX_RIGHT_READ`,
    /// `ZX_RIGHT_WRITE` (required for [`zx_interrupt_ack()`]), `ZX_RIGHT_WAIT` (required for
    /// [`zx_interrupt_wait()`], and `ZX_RIGHT_SIGNAL` (required for [`zx_interrupt_trigger()`]).
    ///
    /// Interrupts are said to be "triggered" when the underlying physical interrupt occurs
    /// or when [`zx_interrupt_trigger()`] is called on a virtual interrupt.  A triggered interrupt,
    /// when bound to a port with [`zx_interrupt_bind()`], causes a packet to be delivered to the port.
    ///
    /// If not bound to a port, an interrupt object may be waited on with [`zx_interrupt_wait()`].
    ///
    /// Interrupts cannot be waited on with the `zx_object_wait_` family of calls.
    ///
    /// ## Rights
    ///
    /// *src_obj* must have resource kind `ZX_RSRC_KIND_IRQ`.
    ///
    /// ## Return value
    ///
    /// `zx_interrupt_create()` returns `ZX_OK` on success. In the event
    /// of failure, a negative error value is returned.
    ///
    /// ## Errors
    ///
    /// `ZX_ERR_BAD_HANDLE` the *src_obj* handle is invalid (if this is not a virtual interrupt)
    ///
    /// `ZX_ERR_WRONG_TYPE` the *src_obj* handle is not of an appropriate type to create an interrupt.
    ///
    /// `ZX_ERR_ACCESS_DENIED` the *src_obj* handle does not allow this operation.
    ///
    /// `ZX_ERR_INVALID_ARGS` *options* contains invalid flags or the *out_handle*
    /// parameter is an invalid pointer.
    ///
    /// `ZX_ERR_NO_MEMORY`  Failure due to lack of memory.
    /// There is no good way for userspace to handle this (unlikely) error.
    /// In a future build this error will no longer occur.
    ///
    /// ## See also
    ///
    ///  - [`zx_handle_close()`]
    ///  - [`zx_interrupt_ack()`]
    ///  - [`zx_interrupt_bind()`]
    ///  - [`zx_interrupt_destroy()`]
    ///  - [`zx_interrupt_wait()`]
    ///  - [`zx_port_wait()`]
    ///
    /// [`zx_channel_write()`]: channel_write.md
    /// [`zx_handle_close()`]: handle_close.md
    /// [`zx_interrupt_ack()`]: interrupt_ack.md
    /// [`zx_interrupt_bind()`]: interrupt_bind.md
    /// [`zx_interrupt_destroy()`]: interrupt_destroy.md
    /// [`zx_interrupt_trigger()`]: interrupt_trigger.md
    /// [`zx_interrupt_wait()`]: interrupt_wait.md
    /// [`zx_port_wait()`]: port_wait.md
    strict Create(resource struct {
        src_obj Handle:RESOURCE;
        src_num uint32;
        options uint32;
    }) -> (resource struct {
        out_handle Handle:INTERRUPT;
    }) error Status;

    /// ## Summary
    ///
    /// Bind an interrupt object to a port.
    ///
    /// ## Declaration
    ///
    /// ```c
    /// #include <zircon/syscalls.h>
    ///
    /// zx_status_t zx_interrupt_bind(zx_handle_t handle,
    ///                               zx_handle_t port_handle,
    ///                               uint64_t key,
    ///                               uint32_t options);
    /// ```
    ///
    /// ## Description
    ///
    /// `zx_interrupt_bind()` binds or unbinds an interrupt object to a port.
    ///
    /// An interrupt object may only be bound to a single port and may only be bound once.
    /// The interrupt can only bind to a port created with `ZX_PORT_BIND_TO_INTERRUPT`
    /// option.
    ///
    /// When a bound interrupt object is triggered, a `ZX_PKT_TYPE_INTERRUPT` packet will
    /// be delivered to the port it is bound to, with the timestamp (relative to `ZX_CLOCK_MONOTONIC`)
    /// of when the interrupt was triggered in the `zx_packet_interrupt_t`.  The *key* used
    /// when binding the interrupt will be present in the `key` field of the `zx_port_packet_t`.
    ///
    /// If the interrupt being bound is in a triggered state, then a
    /// `ZX_PKT_TYPE_INTERRUPT` packet will be sent to the port the interrupt is being bound to,
    /// with the timestamp of when the interrupt was triggered. This packet will need
    /// to be processed normally.
    ///
    /// To bind to a port pass `ZX_INTERRUPT_BIND` in *options*.
    ///
    /// To unbind a previously bound port pass `ZX_INTERRUPT_UNBIND` in *options*. For unbind the
    /// *port_handle* is required but the *key* is ignored. Unbinding the port removes previously
    /// queued packets to the port.
    ///
    /// Before another packet may be delivered, the bound interrupt must be re-armed using the
    /// [`zx_interrupt_ack()`] syscall.  This is (in almost all cases) best done after the interrupt
    /// packet has been fully processed.  Especially in the case of multiple threads reading
    /// packets from a port, if the processing thread re-arms the interrupt and it has triggered,
    /// a packet will immediately be delivered to a waiting thread.
    ///
    /// Interrupt packets are delivered via a dedicated queue on ports and are higher priority
    /// than non-interrupt packets.
    ///
    /// ## Rights
    ///
    /// *handle* must be of type `ZX_OBJ_TYPE_INTERRUPT` and have `ZX_RIGHT_READ`.
    ///
    /// *port_handle* must be of type `ZX_OBJ_TYPE_PORT` and have `ZX_RIGHT_WRITE`.
    ///
    /// ## Return value
    ///
    /// `zx_interrupt_bind()` returns `ZX_OK` on success. In the event
    /// of failure, a negative error value is returned.
    ///
    /// ## Errors
    ///
    /// `ZX_ERR_BAD_HANDLE` *handle* or *port_handle* is not a valid handle.
    ///
    /// `ZX_ERR_WRONG_TYPE` *handle* is not an interrupt object or *port_handle* is not a port object.
    ///
    /// `ZX_ERR_CANCELED`  [`zx_interrupt_destroy()`] was called on *handle*.
    ///
    /// `ZX_ERR_BAD_STATE`  A thread is waiting on the interrupt using [`zx_interrupt_wait()`]
    ///
    /// `ZX_ERR_ACCESS_DENIED` the *handle* handle lacks `ZX_RIGHT_READ` or the *port_handle* handle
    /// lacks `ZX_RIGHT_WRITE`
    ///
    /// `ZX_ERR_ALREADY_BOUND` this interrupt object is already bound.
    ///
    /// `ZX_ERR_INVALID_ARGS` *options* is not `ZX_INTERRUPT_BIND` or `ZX_INTERRUPT_UNBIND`.
    ///
    /// `ZX_ERR_NOT_FOUND` the *port* does not match the bound port.
    ///
    /// ## See also
    ///
    ///  - [`zx_handle_close()`]
    ///  - [`zx_interrupt_ack()`]
    ///  - [`zx_interrupt_create()`]
    ///  - [`zx_interrupt_destroy()`]
    ///  - [`zx_interrupt_trigger()`]
    ///  - [`zx_interrupt_wait()`]
    ///  - [`zx_port_wait()`]
    ///
    /// [`zx_handle_close()`]: handle_close.md
    /// [`zx_interrupt_ack()`]: interrupt_ack.md
    /// [`zx_interrupt_create()`]: interrupt_create.md
    /// [`zx_interrupt_destroy()`]: interrupt_destroy.md
    /// [`zx_interrupt_trigger()`]: interrupt_trigger.md
    /// [`zx_interrupt_wait()`]: interrupt_wait.md
    /// [`zx_port_wait()`]: port_wait.md
    strict Bind(resource struct {
        handle Handle:INTERRUPT;
        port_handle Handle:PORT;
        key uint64;
        options uint32;
    }) -> () error Status;

    /// ## Summary
    ///
    /// Wait for an interrupt.
    ///
    /// ## Declaration
    ///
    /// ```c
    /// #include <zircon/syscalls.h>
    ///
    /// zx_status_t zx_interrupt_wait(zx_handle_t handle, zx_time_t* out_timestamp);
    /// ```
    ///
    /// ## Description
    ///
    /// `zx_interrupt_wait()` is a blocking syscall that causes the caller to
    /// wait until an interrupt is triggered.  It can only be used on interrupt
    /// objects that have not been bound to a port with [`zx_interrupt_bind()`]
    ///
    /// It also, before the waiting begins, will acknowledge the interrupt object,
    /// as if [`zx_interrupt_ack()`] were called on it.
    ///
    /// The wait may be aborted with [`zx_interrupt_destroy()`] or by closing the handle.
    ///
    /// ## Rights
    ///
    /// *handle* must be of type `ZX_OBJ_TYPE_INTERRUPT` and have `ZX_RIGHT_WAIT`.
    ///
    /// ## Return value
    ///
    /// `zx_interrupt_wait()` returns `ZX_OK` on success, and *out_timestamp*, if
    /// non-NULL, returns the timestamp of when the interrupt was triggered (relative
    /// to `ZX_CLOCK_MONOTONIC`)
    ///
    /// ## Errors
    ///
    /// `ZX_ERR_BAD_HANDLE` *handle* is an invalid handle.
    ///
    /// `ZX_ERR_WRONG_TYPE` *handle* is not a handle to an interrupt object.
    ///
    /// `ZX_ERR_BAD_STATE` the interrupt object is bound to a port.
    ///
    /// `ZX_ERR_ACCESS_DENIED` *handle* lacks `ZX_RIGHT_WAIT`.
    ///
    /// `ZX_ERR_CANCELED`  *handle* was closed while waiting or [`zx_interrupt_destroy()`] was called
    /// on it.
    ///
    /// `ZX_ERR_INVALID_ARGS` the *out_timestamp* parameter is an invalid pointer.
    ///
    /// ## See also
    ///
    ///  - [`zx_handle_close()`]
    ///  - [`zx_interrupt_ack()`]
    ///  - [`zx_interrupt_bind()`]
    ///  - [`zx_interrupt_create()`]
    ///  - [`zx_interrupt_destroy()`]
    ///  - [`zx_interrupt_trigger()`]
    ///  - [`zx_port_wait()`]
    ///
    /// [`zx_handle_close()`]: handle_close.md
    /// [`zx_interrupt_ack()`]: interrupt_ack.md
    /// [`zx_interrupt_bind()`]: interrupt_bind.md
    /// [`zx_interrupt_create()`]: interrupt_create.md
    /// [`zx_interrupt_destroy()`]: interrupt_destroy.md
    /// [`zx_interrupt_trigger()`]: interrupt_trigger.md
    /// [`zx_port_wait()`]: port_wait.md
    @blocking
    strict Wait(resource struct {
        handle Handle:INTERRUPT;
    }) -> (struct {
        out_timestamp Time;
    }) error Status;

    // TODO(https://fxbug.dev/42107929): No DESTROY rights here.
    /// ## Summary
    ///
    /// Destroys an interrupt object.
    ///
    /// ## Declaration
    ///
    /// ```c
    /// #include <zircon/syscalls.h>
    ///
    /// zx_status_t zx_interrupt_destroy(zx_handle_t handle);
    /// ```
    ///
    /// ## Description
    ///
    /// `zx_interrupt_destroy()` "destroys" an interrupt object, putting it in a state
    /// where any [`zx_interrupt_wait()`] operations on it will return `ZX_ERR_CANCELED`,
    /// and it is unbound from any ports it was bound to.
    ///
    /// This provides a clean shut down mechanism.  Closing the last handle to the
    /// interrupt object results in similar cancellation but could result in use-after-close
    /// of the handle.
    ///
    /// If the interrupt object is bound to a port when cancellation happens, if it
    /// has not yet triggered, or it has triggered but the packet has not yet been
    /// received by a caller of [`zx_port_wait()`], success is returned and any packets
    /// in flight are removed.  Otherwise, `ZX_ERR_NOT_FOUND` is returned, indicating
    /// that the packet has been read but the interrupt has not been re-armed by calling
    /// [`zx_interrupt_ack()`].
    ///
    /// ## Rights
    ///
    /// TODO(https://fxbug.dev/42107318)
    ///
    /// ## Return value
    ///
    /// `zx_interrupt_destroy()` returns `ZX_OK` on success. In the event
    /// of failure, a negative error value is returned.
    ///
    /// ## Errors
    ///
    /// `ZX_ERR_BAD_HANDLE` *handle* is an invalid handle.
    ///
    /// `ZX_ERR_WRONG_TYPE` *handle* is not an interrupt object.
    ///
    /// `ZX_ERR_NOT_FOUND`  *handle* was bound (and now no longer is) but was not
    /// being waited for.
    ///
    /// `ZX_ERR_ACCESS_DENIED` *handle* lacks `ZX_RIGHT_WRITE`.
    ///
    /// ## See also
    ///
    ///  - [`zx_handle_close()`]
    ///  - [`zx_interrupt_ack()`]
    ///  - [`zx_interrupt_bind()`]
    ///  - [`zx_interrupt_create()`]
    ///  - [`zx_interrupt_trigger()`]
    ///  - [`zx_interrupt_wait()`]
    ///  - [`zx_port_wait()`]
    ///
    /// [`zx_handle_close()`]: handle_close.md
    /// [`zx_interrupt_ack()`]: interrupt_ack.md
    /// [`zx_interrupt_bind()`]: interrupt_bind.md
    /// [`zx_interrupt_create()`]: interrupt_create.md
    /// [`zx_interrupt_trigger()`]: interrupt_trigger.md
    /// [`zx_interrupt_wait()`]: interrupt_wait.md
    /// [`zx_port_wait()`]: port_wait.md
    strict Destroy(resource struct {
        handle Handle:INTERRUPT;
    }) -> () error Status;

    /// ## Summary
    ///
    /// Acknowledge an interrupt and re-arm it.
    ///
    /// ## Declaration
    ///
    /// ```c
    /// #include <zircon/syscalls.h>
    ///
    /// zx_status_t zx_interrupt_ack(zx_handle_t handle);
    /// ```
    ///
    /// ## Description
    ///
    /// `zx_interrupt_ack()` acknowledges an interrupt object, causing it to be eligible
    /// to trigger again (and delivering a packet to the port it is bound to).
    ///
    /// If the interrupt object is a physical interrupt, if it is a level interrupt and
    /// still asserted, or is an edge interrupt that has been asserted since it last
    /// triggered, the interrupt will trigger immediately, delivering a packet to the
    /// port it is bound to.
    ///
    /// Virtual interrupts behave as edge interrupts.
    ///
    /// This syscall only operates on interrupts bound to a port.  Interrupts
    /// being waited upon with [`zx_interrupt_wait()`] do not need to be re-armed with this
    /// call -- it happens automatically when [`zx_interrupt_wait()`] is called.
    ///
    /// ## Rights
    ///
    /// *handle* must be of type `ZX_OBJ_TYPE_INTERRUPT` and have `ZX_RIGHT_WRITE`.
    ///
    /// ## Return value
    ///
    /// `zx_interrupt_ack()` returns `ZX_OK` on success. In the event
    /// of failure, a negative error value is returned.
    ///
    /// ## Errors
    ///
    /// `ZX_ERR_BAD_HANDLE` *handle* is an invalid handle.
    ///
    /// `ZX_ERR_WRONG_TYPE` *handle* is not an interrupt object.
    ///
    /// `ZX_ERR_BAD_STATE` *handle* is not bound to a port.
    ///
    /// `ZX_ERR_CANCELED`  [`zx_interrupt_destroy()`] was called on *handle*.
    ///
    /// `ZX_ERR_ACCESS_DENIED` *handle* lacks `ZX_RIGHT_WRITE`.
    ///
    /// ## See also
    ///
    ///  - [`zx_handle_close()`]
    ///  - [`zx_interrupt_bind()`]
    ///  - [`zx_interrupt_create()`]
    ///  - [`zx_interrupt_destroy()`]
    ///  - [`zx_interrupt_trigger()`]
    ///  - [`zx_interrupt_wait()`]
    ///  - [`zx_port_wait()`]
    ///
    /// [`zx_handle_close()`]: handle_close.md
    /// [`zx_interrupt_bind()`]: interrupt_bind.md
    /// [`zx_interrupt_create()`]: interrupt_create.md
    /// [`zx_interrupt_destroy()`]: interrupt_destroy.md
    /// [`zx_interrupt_trigger()`]: interrupt_trigger.md
    /// [`zx_interrupt_wait()`]: interrupt_wait.md
    /// [`zx_port_wait()`]: port_wait.md
    strict Ack(resource struct {
        handle Handle:INTERRUPT;
    }) -> () error Status;

    /// ## Summary
    ///
    /// Triggers a virtual interrupt object.
    ///
    /// ## Declaration
    ///
    /// ```c
    /// #include <zircon/syscalls.h>
    ///
    /// zx_status_t zx_interrupt_trigger(zx_handle_t handle,
    ///                                  uint32_t options,
    ///                                  zx_time_t timestamp);
    /// ```
    ///
    /// ## Description
    ///
    /// `zx_interrupt_trigger()` is used to trigger a virtual interrupt interrupt object,
    /// causing an interrupt message packet to arrive on the bound port, if it is bound
    /// to a port, or [`zx_interrupt_wait()`] to return if it is waiting on this interrupt.
    ///
    /// *options* must be zero.
    ///
    /// ## Rights
    ///
    /// *handle* must be of type `ZX_OBJ_TYPE_INTERRUPT` and have `ZX_RIGHT_SIGNAL`.
    ///
    /// ## Return value
    ///
    /// `zx_interrupt_trigger()` returns `ZX_OK` on success. In the event
    /// of failure, a negative error value is returned.
    ///
    /// ## Errors
    ///
    /// `ZX_ERR_BAD_HANDLE` *handle* is an invalid handle.
    ///
    /// `ZX_ERR_WRONG_TYPE` *handle* is not an interrupt object.
    ///
    /// `ZX_ERR_BAD_STATE` *handle* is not a virtual interrupt.
    ///
    /// `ZX_ERR_CANCELED`  [`zx_interrupt_destroy()`] was called on *handle*.
    ///
    /// `ZX_ERR_ACCESS_DENIED` *handle* lacks `ZX_RIGHT_SIGNAL`.
    ///
    /// `ZX_ERR_INVALID_ARGS` *options* is non-zero.
    ///
    /// ## See also
    ///
    ///  - [`zx_handle_close()`]
    ///  - [`zx_interrupt_ack()`]
    ///  - [`zx_interrupt_bind()`]
    ///  - [`zx_interrupt_create()`]
    ///  - [`zx_interrupt_destroy()`]
    ///  - [`zx_interrupt_wait()`]
    ///  - [`zx_port_wait()`]
    ///
    /// [`zx_handle_close()`]: handle_close.md
    /// [`zx_interrupt_ack()`]: interrupt_ack.md
    /// [`zx_interrupt_bind()`]: interrupt_bind.md
    /// [`zx_interrupt_create()`]: interrupt_create.md
    /// [`zx_interrupt_destroy()`]: interrupt_destroy.md
    /// [`zx_interrupt_wait()`]: interrupt_wait.md
    /// [`zx_port_wait()`]: port_wait.md
    strict Trigger(resource struct {
        handle Handle:INTERRUPT;
        options uint32;
        timestamp Time;
    }) -> () error Status;
};