/* SPDX-License-Identifier: GPL-2.0 */
|
/*
|
* Gasket common interrupt module. Defines functions for enabling
|
* eventfd-triggered interrupts between a Gasket device and a host process.
|
*
|
* Copyright (C) 2018 Google, Inc.
|
*/
|
#ifndef __GASKET_INTERRUPT_H__
|
#define __GASKET_INTERRUPT_H__
|
|
#include <linux/eventfd.h>
|
#include <linux/pci.h>
|
|
#include "gasket_core.h"
|
|
/* Note that this currently assumes that device interrupts are a dense set,
|
* numbered from 0 - (num_interrupts - 1). Should this have to change, these
|
* APIs will have to be updated.
|
*/
|
|
/* Opaque type used to hold interrupt subsystem data. */
|
struct gasket_interrupt_data;
|
|
/*
|
* Initialize the interrupt module.
|
* @gasket_dev: The Gasket device structure for the device to be initted.
|
* @type: Type of the interrupt. (See gasket_interrupt_type).
|
* @name: The name to associate with these interrupts.
|
* @interrupts: An array of all interrupt descriptions for this device.
|
* @num_interrupts: The length of the @interrupts array.
|
* @pack_width: The width, in bits, of a single field in a packed interrupt reg.
|
* @bar_index: The bar containing all interrupt registers.
|
*
|
* Allocates and initializes data to track interrupt state for a device.
|
* After this call, no interrupts will be configured/delivered; call
|
* gasket_interrupt_set_vector[_packed] to associate each interrupt with an
|
* __iomem location, then gasket_interrupt_set_eventfd to associate an eventfd
|
* with an interrupt.
|
*
|
* If num_interrupts interrupts are not available, this call will return a
|
* negative error code. In that case, gasket_interrupt_cleanup should still be
|
* called. Returns 0 on success (which can include a device where interrupts
|
* are not possible to set up, but is otherwise OK; that device will report
|
* status LAMED.)
|
*/
|
int gasket_interrupt_init(struct gasket_dev *gasket_dev, const char *name,
|
int type,
|
const struct gasket_interrupt_desc *interrupts,
|
int num_interrupts, int pack_width, int bar_index,
|
const struct gasket_wire_interrupt_offsets *wire_int_offsets);
|
|
/*
|
* Clean up a device's interrupt structure.
|
* @gasket_dev: The Gasket information structure for this device.
|
*
|
* Cleans up the device's interrupts and deallocates data.
|
*/
|
void gasket_interrupt_cleanup(struct gasket_dev *gasket_dev);
|
|
/*
|
* Clean up and re-initialize the MSI-x subsystem.
|
* @gasket_dev: The Gasket information structure for this device.
|
*
|
* Performs a teardown of the MSI-x subsystem and re-initializes it. Does not
|
* free the underlying data structures. Returns 0 on success and an error code
|
* on error.
|
*/
|
int gasket_interrupt_reinit(struct gasket_dev *gasket_dev);
|
|
/*
|
* Reset the counts stored in the interrupt subsystem.
|
* @gasket_dev: The Gasket information structure for this device.
|
*
|
* Sets the counts of all interrupts in the subsystem to 0.
|
*/
|
int gasket_interrupt_reset_counts(struct gasket_dev *gasket_dev);
|
|
/*
|
* Associates an eventfd with a device interrupt.
|
* @data: Pointer to device interrupt data.
|
* @interrupt: The device interrupt to configure.
|
* @event_fd: The eventfd to associate with the interrupt.
|
*
|
* Prepares the host to receive notification of device interrupts by associating
|
* event_fd with interrupt. Upon receipt of a device interrupt, event_fd will be
|
* signaled, after successful configuration.
|
*
|
* Returns 0 on success, a negative error code otherwise.
|
*/
|
int gasket_interrupt_set_eventfd(struct gasket_interrupt_data *interrupt_data,
|
int interrupt, int event_fd);
|
|
/*
|
* Removes an interrupt-eventfd association.
|
* @data: Pointer to device interrupt data.
|
* @interrupt: The device interrupt to de-associate.
|
*
|
* Removes any eventfd associated with the specified interrupt, if any.
|
*/
|
int gasket_interrupt_clear_eventfd(struct gasket_interrupt_data *interrupt_data,
|
int interrupt);
|
|
/*
|
* The below functions exist for backwards compatibility.
|
* No new uses should be written.
|
*/
|
/*
|
* Get the health of the interrupt subsystem.
|
* @gasket_dev: The Gasket device struct.
|
*
|
* Returns DEAD if not set up, LAMED if initialization failed, and ALIVE
|
* otherwise.
|
*/
|
|
int gasket_interrupt_system_status(struct gasket_dev *gasket_dev);
|
|
#endif
|
