diff options
Diffstat (limited to 'drivers/net/ethernet/intel/ice/ice_irq.c')
| -rw-r--r-- | drivers/net/ethernet/intel/ice/ice_irq.c | 378 |
1 files changed, 378 insertions, 0 deletions
diff --git a/drivers/net/ethernet/intel/ice/ice_irq.c b/drivers/net/ethernet/intel/ice/ice_irq.c new file mode 100644 index 000000000000..ad82ff7d1995 --- /dev/null +++ b/drivers/net/ethernet/intel/ice/ice_irq.c @@ -0,0 +1,378 @@ +// 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) +{ + pf->irq_tracker.num_entries = max_vectors; + pf->irq_tracker.num_static = num_static; + xa_init_flags(&pf->irq_tracker.entries, XA_FLAGS_ALLOC); +} + +/** + * ice_deinit_irq_tracker - free xarray tracker + * @pf: board private structure + */ +static void ice_deinit_irq_tracker(struct ice_pf *pf) +{ + xa_destroy(&pf->irq_tracker.entries); +} + +/** + * 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) +{ + struct ice_irq_entry *entry; + + entry = xa_erase(&pf->irq_tracker.entries, index); + kfree(entry); +} + +/** + * 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) +{ + struct xa_limit limit = { .max = pf->irq_tracker.num_entries, + .min = 0 }; + unsigned int num_static = pf->irq_tracker.num_static; + struct ice_irq_entry *entry; + unsigned int index; + int ret; + + entry = kzalloc(sizeof(*entry), GFP_KERNEL); + if (!entry) + return NULL; + + /* skip preallocated entries if the caller says so */ + if (dyn_only) + limit.min = num_static; + + ret = xa_alloc(&pf->irq_tracker.entries, &index, entry, limit, + GFP_KERNEL); + + if (ret) { + kfree(entry); + entry = NULL; + } else { + entry->index = index; + entry->dynamic = index >= num_static; + } + + return entry; +} + +/** + * 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) +{ + int v_rdma; + + if (!ice_is_rdma_ena(pf)) { + pf->num_lan_msix = v_remain; + return; + } + + /* RDMA needs at least 1 interrupt in addition to AEQ MSIX */ + v_rdma = ICE_RDMA_NUM_AEQ_MSIX + 1; + + if (v_remain < ICE_MIN_LAN_TXRX_MSIX + ICE_MIN_RDMA_MSIX) { + dev_warn(ice_pf_to_dev(pf), "Not enough MSI-X vectors to support RDMA.\n"); + clear_bit(ICE_FLAG_RDMA_ENA, pf->flags); + + pf->num_rdma_msix = 0; + pf->num_lan_msix = ICE_MIN_LAN_TXRX_MSIX; + } else if ((v_remain < ICE_MIN_LAN_TXRX_MSIX + v_rdma) || + (v_remain - v_rdma < v_rdma)) { + /* Support minimum RDMA and give remaining vectors to LAN MSIX + */ + pf->num_rdma_msix = ICE_MIN_RDMA_MSIX; + pf->num_lan_msix = v_remain - ICE_MIN_RDMA_MSIX; + } else { + /* Split remaining MSIX with RDMA after accounting for AEQ MSIX + */ + pf->num_rdma_msix = (v_remain - ICE_RDMA_NUM_AEQ_MSIX) / 2 + + ICE_RDMA_NUM_AEQ_MSIX; + pf->num_lan_msix = v_remain - pf->num_rdma_msix; + } +} + +/** + * 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) +{ + int num_cpus, hw_num_msix, v_other, v_wanted, v_actual; + struct device *dev = ice_pf_to_dev(pf); + int err; + + hw_num_msix = pf->hw.func_caps.common_cap.num_msix_vectors; + num_cpus = num_online_cpus(); + + /* LAN miscellaneous handler */ + v_other = ICE_MIN_LAN_OICR_MSIX; + + /* Flow Director */ + if (test_bit(ICE_FLAG_FD_ENA, pf->flags)) + v_other += ICE_FDIR_MSIX; + + /* switchdev */ + v_other += ICE_ESWITCH_MSIX; + + v_wanted = v_other; + + /* LAN traffic */ + pf->num_lan_msix = num_cpus; + v_wanted += pf->num_lan_msix; + + /* RDMA auxiliary driver */ + if (ice_is_rdma_ena(pf)) { + pf->num_rdma_msix = num_cpus + ICE_RDMA_NUM_AEQ_MSIX; + v_wanted += pf->num_rdma_msix; + } + + if (v_wanted > hw_num_msix) { + int v_remain; + + dev_warn(dev, "not enough device MSI-X vectors. wanted = %d, available = %d\n", + v_wanted, hw_num_msix); + + if (hw_num_msix < ICE_MIN_MSIX) { + err = -ERANGE; + goto exit_err; + } + + v_remain = hw_num_msix - v_other; + if (v_remain < ICE_MIN_LAN_TXRX_MSIX) { + v_other = ICE_MIN_MSIX - ICE_MIN_LAN_TXRX_MSIX; + v_remain = ICE_MIN_LAN_TXRX_MSIX; + } + + ice_reduce_msix_usage(pf, v_remain); + v_wanted = pf->num_lan_msix + pf->num_rdma_msix + v_other; + + dev_notice(dev, "Reducing request to %d MSI-X vectors for LAN traffic.\n", + pf->num_lan_msix); + if (ice_is_rdma_ena(pf)) + dev_notice(dev, "Reducing request to %d MSI-X vectors for RDMA.\n", + pf->num_rdma_msix); + } + + /* actually reserve the vectors */ + v_actual = pci_alloc_irq_vectors(pf->pdev, ICE_MIN_MSIX, v_wanted, + PCI_IRQ_MSIX); + if (v_actual < 0) { + dev_err(dev, "unable to reserve MSI-X vectors\n"); + err = v_actual; + goto exit_err; + } + + if (v_actual < v_wanted) { + dev_warn(dev, "not enough OS MSI-X vectors. requested = %d, obtained = %d\n", + v_wanted, v_actual); + + if (v_actual < ICE_MIN_MSIX) { + /* error if we can't get minimum vectors */ + pci_free_irq_vectors(pf->pdev); + err = -ERANGE; + goto exit_err; + } else { + int v_remain = v_actual - v_other; + + if (v_remain < ICE_MIN_LAN_TXRX_MSIX) + v_remain = ICE_MIN_LAN_TXRX_MSIX; + + ice_reduce_msix_usage(pf, v_remain); + + dev_notice(dev, "Enabled %d MSI-X vectors for LAN traffic.\n", + pf->num_lan_msix); + + if (ice_is_rdma_ena(pf)) + dev_notice(dev, "Enabled %d MSI-X vectors for RDMA.\n", + pf->num_rdma_msix); + } + } + + return v_actual; + +exit_err: + pf->num_rdma_msix = 0; + pf->num_lan_msix = 0; + return err; +} + +/** + * 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) +{ + pci_free_irq_vectors(pf->pdev); + ice_deinit_irq_tracker(pf); +} + +/** + * ice_init_interrupt_scheme - Determine proper interrupt scheme + * @pf: board private structure to initialize + */ +int ice_init_interrupt_scheme(struct ice_pf *pf) +{ + int total_vectors = pf->hw.func_caps.common_cap.num_msix_vectors; + int vectors, max_vectors; + + vectors = ice_ena_msix_range(pf); + + if (vectors < 0) + return -ENOMEM; + + if (pci_msix_can_alloc_dyn(pf->pdev)) + max_vectors = total_vectors; + else + max_vectors = vectors; + + ice_init_irq_tracker(pf, max_vectors, vectors); + + return 0; +} + +/** + * 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) +{ + int sriov_base_vector = pf->sriov_base_vector; + struct msi_map map = { .index = -ENOENT }; + struct device *dev = ice_pf_to_dev(pf); + struct ice_irq_entry *entry; + + entry = ice_get_irq_res(pf, dyn_only); + if (!entry) + return map; + + /* fail if we're about to violate SRIOV vectors space */ + if (sriov_base_vector && entry->index >= sriov_base_vector) + goto exit_free_res; + + if (pci_msix_can_alloc_dyn(pf->pdev) && entry->dynamic) { + map = pci_msix_alloc_irq_at(pf->pdev, entry->index, NULL); + if (map.index < 0) + goto exit_free_res; + dev_dbg(dev, "allocated new irq at index %d\n", map.index); + } else { + map.index = entry->index; + map.virq = pci_irq_vector(pf->pdev, map.index); + } + + return map; + +exit_free_res: + dev_err(dev, "Could not allocate irq at idx %d\n", entry->index); + ice_free_irq_res(pf, entry->index); + return map; +} + +/** + * 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) +{ + struct ice_irq_entry *entry; + + entry = xa_load(&pf->irq_tracker.entries, map.index); + + if (!entry) { + dev_err(ice_pf_to_dev(pf), "Failed to get MSIX interrupt entry at index %d", + map.index); + return; + } + + dev_dbg(ice_pf_to_dev(pf), "Free irq at index %d\n", map.index); + + if (entry->dynamic) + pci_msix_free_irq(pf->pdev, map); + + ice_free_irq_res(pf, map.index); +} + +/** + * 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) +{ + unsigned long start, index, max_idx; + void *entry; + + /* Treat all preallocated interrupts as used */ + start = pf->irq_tracker.num_static; + max_idx = start - 1; + + xa_for_each_start(&pf->irq_tracker.entries, index, entry, start) { + if (index > max_idx) + max_idx = index; + } + + return max_idx; +} |