1 files changed, 275 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..30801fd375f0
--- /dev/null
+++ b/drivers/net/ethernet/intel/ice/ice_irq.c
@@ -0,0 +1,275 @@
+// 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);
+}
+
+static int
+ice_init_virt_irq_tracker(struct ice_pf *pf, u32 base, u32 num_entries)
+{
+	pf->virt_irq_tracker.bm = bitmap_zalloc(num_entries, GFP_KERNEL);
+	if (!pf->virt_irq_tracker.bm)
+		return -ENOMEM;
+
+	pf->virt_irq_tracker.num_entries = num_entries;
+	pf->virt_irq_tracker.base = base;
+
+	return 0;
+}
+
+/**
+ * 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);
+}
+
+static void ice_deinit_virt_irq_tracker(struct ice_pf *pf)
+{
+	bitmap_free(pf->virt_irq_tracker.bm);
+}
+
+/**
+ * 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_allowed: allow 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_allowed)
+{
+	struct xa_limit limit = { .max = pf->irq_tracker.num_entries - 1,
+				  .min = 0 };
+	unsigned int num_static = pf->irq_tracker.num_static - 1;
+	struct ice_irq_entry *entry;
+	unsigned int index;
+	int ret;
+
+	entry = kzalloc(sizeof(*entry), GFP_KERNEL);
+	if (!entry)
+		return NULL;
+
+	/* only already allocated if the caller says so */
+	if (!dyn_allowed)
+		limit.max = 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;
+}
+
+#define ICE_RDMA_AEQ_MSIX 1
+static int ice_get_default_msix_amount(struct ice_pf *pf)
+{
+	return ICE_MIN_LAN_OICR_MSIX + num_online_cpus() +
+	       (test_bit(ICE_FLAG_FD_ENA, pf->flags) ? ICE_FDIR_MSIX : 0) +
+	       (ice_is_rdma_ena(pf) ? num_online_cpus() + ICE_RDMA_AEQ_MSIX : 0);
+}
+
+/**
+ * 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_deinit_virt_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;
+
+	/* load default PF MSI-X range */
+	if (!pf->msix.min)
+		pf->msix.min = ICE_MIN_MSIX;
+
+	if (!pf->msix.max)
+		pf->msix.max = min(total_vectors,
+				   ice_get_default_msix_amount(pf));
+
+	pf->msix.total = total_vectors;
+	pf->msix.rest = total_vectors - pf->msix.max;
+
+	if (pci_msix_can_alloc_dyn(pf->pdev))
+		vectors = pf->msix.min;
+	else
+		vectors = pf->msix.max;
+
+	vectors = pci_alloc_irq_vectors(pf->pdev, pf->msix.min, vectors,
+					PCI_IRQ_MSIX);
+	if (vectors < 0)
+		return vectors;
+
+	ice_init_irq_tracker(pf, pf->msix.max, vectors);
+
+	return ice_init_virt_irq_tracker(pf, pf->msix.max, pf->msix.rest);
+}
+
+/**
+ * ice_alloc_irq - Allocate new interrupt vector
+ * @pf: board private structure
+ * @dyn_allowed: allow 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_allowed 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_allowed)
+{
+	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_allowed);
+	if (!entry)
+		return map;
+
+	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_virt_get_irqs - get irqs for SR-IOV usacase
+ * @pf: pointer to PF structure
+ * @needed: number of irqs to get
+ *
+ * This returns the first MSI-X vector index in PF space that is used by this
+ * VF. This index is used when accessing PF relative registers such as
+ * GLINT_VECT2FUNC and GLINT_DYN_CTL.
+ * This will always be the OICR index in the AVF driver so any functionality
+ * using vf->first_vector_idx for queue configuration_id: id of VF which will
+ * use this irqs
+ */
+int ice_virt_get_irqs(struct ice_pf *pf, u32 needed)
+{
+	int res = bitmap_find_next_zero_area(pf->virt_irq_tracker.bm,
+					     pf->virt_irq_tracker.num_entries,
+					     0, needed, 0);
+
+	if (res >= pf->virt_irq_tracker.num_entries)
+		return -ENOENT;
+
+	bitmap_set(pf->virt_irq_tracker.bm, res, needed);
+
+	/* conversion from number in bitmap to global irq index */
+	return res + pf->virt_irq_tracker.base;
+}
+
+/**
+ * ice_virt_free_irqs - free irqs used by the VF
+ * @pf: pointer to PF structure
+ * @index: first index to be free
+ * @irqs: number of irqs to free
+ */
+void ice_virt_free_irqs(struct ice_pf *pf, u32 index, u32 irqs)
+{
+	bitmap_clear(pf->virt_irq_tracker.bm, index - pf->virt_irq_tracker.base,
+		     irqs);
+}