linux/drivers/net/ethernet/intel/ice/ice_irq.c

// SPDX-License-Identifier: GPL-2.0
/* Copyright (C) 2023, Intel Corporation. */

#include "ice.h"
#include "ice_lib.h"
#include "ice_irq.h"

/**
 * ice_init_irq_tracker - initialize interrupt tracker
 * @pf: board private structure
 * @max_vectors: maximum number of vectors that tracker can hold
 * @num_static: number of preallocated interrupts
 */
static void
ice_init_irq_tracker(struct ice_pf *pf, unsigned int max_vectors,
		     unsigned int num_static)
{ … }

/**
 * ice_deinit_irq_tracker - free xarray tracker
 * @pf: board private structure
 */
static void ice_deinit_irq_tracker(struct ice_pf *pf)
{ … }

/**
 * ice_free_irq_res - free a block of resources
 * @pf: board private structure
 * @index: starting index previously returned by ice_get_res
 */
static void ice_free_irq_res(struct ice_pf *pf, u16 index)
{ … }

/**
 * ice_get_irq_res - get an interrupt resource
 * @pf: board private structure
 * @dyn_only: force entry to be dynamically allocated
 *
 * Allocate new irq entry in the free slot of the tracker. Since xarray
 * is used, always allocate new entry at the lowest possible index. Set
 * proper allocation limit for maximum tracker entries.
 *
 * Returns allocated irq entry or NULL on failure.
 */
static struct ice_irq_entry *ice_get_irq_res(struct ice_pf *pf, bool dyn_only)
{ … }

/**
 * ice_reduce_msix_usage - Reduce usage of MSI-X vectors
 * @pf: board private structure
 * @v_remain: number of remaining MSI-X vectors to be distributed
 *
 * Reduce the usage of MSI-X vectors when entire request cannot be fulfilled.
 * pf->num_lan_msix and pf->num_rdma_msix values are set based on number of
 * remaining vectors.
 */
static void ice_reduce_msix_usage(struct ice_pf *pf, int v_remain)
{ … }

/**
 * ice_ena_msix_range - Request a range of MSIX vectors from the OS
 * @pf: board private structure
 *
 * Compute the number of MSIX vectors wanted and request from the OS. Adjust
 * device usage if there are not enough vectors. Return the number of vectors
 * reserved or negative on failure.
 */
static int ice_ena_msix_range(struct ice_pf *pf)
{ … }

/**
 * ice_clear_interrupt_scheme - Undo things done by ice_init_interrupt_scheme
 * @pf: board private structure
 */
void ice_clear_interrupt_scheme(struct ice_pf *pf)
{ … }

/**
 * ice_init_interrupt_scheme - Determine proper interrupt scheme
 * @pf: board private structure to initialize
 */
int ice_init_interrupt_scheme(struct ice_pf *pf)
{ … }

/**
 * ice_alloc_irq - Allocate new interrupt vector
 * @pf: board private structure
 * @dyn_only: force dynamic allocation of the interrupt
 *
 * Allocate new interrupt vector for a given owner id.
 * return struct msi_map with interrupt details and track
 * allocated interrupt appropriately.
 *
 * This function reserves new irq entry from the irq_tracker.
 * if according to the tracker information all interrupts that
 * were allocated with ice_pci_alloc_irq_vectors are already used
 * and dynamically allocated interrupts are supported then new
 * interrupt will be allocated with pci_msix_alloc_irq_at.
 *
 * Some callers may only support dynamically allocated interrupts.
 * This is indicated with dyn_only flag.
 *
 * On failure, return map with negative .index. The caller
 * is expected to check returned map index.
 *
 */
struct msi_map ice_alloc_irq(struct ice_pf *pf, bool dyn_only)
{ … }

/**
 * ice_free_irq - Free interrupt vector
 * @pf: board private structure
 * @map: map with interrupt details
 *
 * Remove allocated interrupt from the interrupt tracker. If interrupt was
 * allocated dynamically, free respective interrupt vector.
 */
void ice_free_irq(struct ice_pf *pf, struct msi_map map)
{ … }

/**
 * ice_get_max_used_msix_vector - Get the max used interrupt vector
 * @pf: board private structure
 *
 * Return index of maximum used interrupt vectors with respect to the
 * beginning of the MSIX table. Take into account that some interrupts
 * may have been dynamically allocated after MSIX was initially enabled.
 */
int ice_get_max_used_msix_vector(struct ice_pf *pf)
{ … }