nfp: allocate irqs in lower driver

PF services multiple ports using single PCI device therefore
IRQs can no longer be allocated in the netdev code.  Lower
portion of the driver has to allocate the IRQs and hand them
out to ports.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 73 insertions, 71 deletions

diff --git a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
index 6ac43abf561b..074259cc8e06 100644
--- a/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
+++ b/drivers/net/ethernet/netronome/nfp/nfp_net_common.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2015 Netronome Systems, Inc.
+ * Copyright (C) 2015-2017 Netronome Systems, Inc.
  *
  * This software is dual licensed under the GNU General License Version 2,
  * June 1991 as shown in the file COPYING in the top-level directory of this
@@ -281,72 +281,76 @@ static void nfp_net_irq_unmask(struct nfp_net *nn, unsigned int entry_nr)
 }
 
 /**
- * nfp_net_msix_alloc() - Try to allocate MSI-X irqs
- * @nn:       NFP Network structure
- * @nr_vecs:  Number of MSI-X vectors to allocate
- *
- * For MSI-X we want at least NFP_NET_NON_Q_VECTORS + 1 vectors.
+ * nfp_net_irqs_alloc() - allocates MSI-X irqs
+ * @pdev:        PCI device structure
+ * @irq_entries: Array to be initialized and used to hold the irq entries
+ * @min_irqs:    Minimal acceptable number of interrupts
+ * @wanted_irqs: Target number of interrupts to allocate
  *
- * Return: Number of MSI-X vectors obtained or 0 on error.
+ * Return: Number of irqs obtained or 0 on error.
  */
-static int nfp_net_msix_alloc(struct nfp_net *nn, int nr_vecs)
+unsigned int
+nfp_net_irqs_alloc(struct pci_dev *pdev, struct msix_entry *irq_entries,
+		   unsigned int min_irqs, unsigned int wanted_irqs)
 {
-	struct pci_dev *pdev = nn->pdev;
-	int nvecs;
-	int i;
+	unsigned int i;
+	int got_irqs;
 
-	for (i = 0; i < nr_vecs; i++)
-		nn->irq_entries[i].entry = i;
+	for (i = 0; i < wanted_irqs; i++)
+		irq_entries[i].entry = i;
 
-	nvecs = pci_enable_msix_range(pdev, nn->irq_entries,
-				      NFP_NET_NON_Q_VECTORS + 1, nr_vecs);
-	if (nvecs < 0) {
-		nn_warn(nn, "Failed to enable MSI-X. Wanted %d-%d (err=%d)\n",
-			NFP_NET_NON_Q_VECTORS + 1, nr_vecs, nvecs);
+	got_irqs = pci_enable_msix_range(pdev, irq_entries,
+					 min_irqs, wanted_irqs);
+	if (got_irqs < 0) {
+		dev_err(&pdev->dev, "Failed to enable %d-%d MSI-X (err=%d)\n",
+			min_irqs, wanted_irqs, got_irqs);
 		return 0;
 	}
 
-	return nvecs;
+	if (got_irqs < wanted_irqs)
+		dev_warn(&pdev->dev, "Unable to allocate %d IRQs got only %d\n",
+			 wanted_irqs, got_irqs);
+
+	return got_irqs;
 }
 
 /**
- * nfp_net_irqs_alloc() - allocates MSI-X irqs
- * @nn:       NFP Network structure
+ * nfp_net_irqs_assign() - Assign interrupts allocated externally to netdev
+ * @nn:		 NFP Network structure
+ * @irq_entries: Table of allocated interrupts
+ * @n:		 Size of @irq_entries (number of entries to grab)
  *
- * Return: Number of irqs obtained or 0 on error.
+ * After interrupts are allocated with nfp_net_irqs_alloc() this function
+ * should be called to assign them to a specific netdev (port).
  */
-int nfp_net_irqs_alloc(struct nfp_net *nn)
+void
+nfp_net_irqs_assign(struct nfp_net *nn, struct msix_entry *irq_entries,
+		    unsigned int n)
 {
-	int wanted_irqs;
-	unsigned int n;
-
-	wanted_irqs = nn->num_r_vecs + NFP_NET_NON_Q_VECTORS;
-
-	n = nfp_net_msix_alloc(nn, wanted_irqs);
-	if (n == 0) {
-		nn_err(nn, "Failed to allocate MSI-X IRQs\n");
-		return 0;
-	}
-
 	nn->max_r_vecs = n - NFP_NET_NON_Q_VECTORS;
 	nn->num_r_vecs = nn->max_r_vecs;
 
-	if (n < wanted_irqs)
-		nn_warn(nn, "Unable to allocate %d vectors. Got %d instead\n",
-			wanted_irqs, n);
+	memcpy(nn->irq_entries, irq_entries, sizeof(*irq_entries) * n);
 
-	return n;
+	if (nn->num_rx_rings > nn->num_r_vecs ||
+	    nn->num_tx_rings > nn->num_r_vecs)
+		nn_warn(nn, "More rings (%d,%d) than vectors (%d).\n",
+			nn->num_rx_rings, nn->num_tx_rings, nn->num_r_vecs);
+
+	nn->num_rx_rings = min(nn->num_r_vecs, nn->num_rx_rings);
+	nn->num_tx_rings = min(nn->num_r_vecs, nn->num_tx_rings);
+	nn->num_stack_tx_rings = nn->num_tx_rings;
 }
 
 /**
  * nfp_net_irqs_disable() - Disable interrupts
- * @nn:       NFP Network structure
+ * @pdev:        PCI device structure
  *
  * Undoes what @nfp_net_irqs_alloc() does.
  */
-void nfp_net_irqs_disable(struct nfp_net *nn)
+void nfp_net_irqs_disable(struct pci_dev *pdev)
 {
-	pci_disable_msix(nn->pdev);
+	pci_disable_msix(pdev);
 }
 
 /**
@@ -410,10 +414,13 @@ out:
 static irqreturn_t nfp_net_irq_lsc(int irq, void *data)
 {
 	struct nfp_net *nn = data;
+	struct msix_entry *entry;
+
+	entry = &nn->irq_entries[NFP_NET_IRQ_LSC_IDX];
 
 	nfp_net_read_link_status(nn);
 
-	nfp_net_irq_unmask(nn, NFP_NET_IRQ_LSC_IDX);
+	nfp_net_irq_unmask(nn, entry->entry);
 
 	return IRQ_HANDLED;
 }
@@ -476,32 +483,28 @@ nfp_net_rx_ring_init(struct nfp_net_rx_ring *rx_ring,
 }
 
 /**
- * nfp_net_irqs_assign() - Assign IRQs and setup rvecs.
+ * nfp_net_vecs_init() - Assign IRQs and setup rvecs.
  * @netdev:   netdev structure
  */
-static void nfp_net_irqs_assign(struct net_device *netdev)
+static void nfp_net_vecs_init(struct net_device *netdev)
 {
 	struct nfp_net *nn = netdev_priv(netdev);
 	struct nfp_net_r_vector *r_vec;
 	int r;
 
-	if (nn->num_rx_rings > nn->num_r_vecs ||
-	    nn->num_tx_rings > nn->num_r_vecs)
-		nn_warn(nn, "More rings (%d,%d) than vectors (%d).\n",
-			nn->num_rx_rings, nn->num_tx_rings, nn->num_r_vecs);
-
-	nn->num_rx_rings = min(nn->num_r_vecs, nn->num_rx_rings);
-	nn->num_tx_rings = min(nn->num_r_vecs, nn->num_tx_rings);
-	nn->num_stack_tx_rings = nn->num_tx_rings;
-
 	nn->lsc_handler = nfp_net_irq_lsc;
 	nn->exn_handler = nfp_net_irq_exn;
 
 	for (r = 0; r < nn->max_r_vecs; r++) {
+		struct msix_entry *entry;
+
+		entry = &nn->irq_entries[NFP_NET_NON_Q_VECTORS + r];
+
 		r_vec = &nn->r_vecs[r];
 		r_vec->nfp_net = nn;
 		r_vec->handler = nfp_net_irq_rxtx;
-		r_vec->irq_idx = NFP_NET_NON_Q_VECTORS + r;
+		r_vec->irq_entry = entry->entry;
+		r_vec->irq_vector = entry->vector;
 
 		cpumask_set_cpu(r, &r_vec->affinity_mask);
 	}
@@ -534,7 +537,7 @@ nfp_net_aux_irq_request(struct nfp_net *nn, u32 ctrl_offset,
 		       entry->vector, err);
 		return err;
 	}
-	nn_writeb(nn, ctrl_offset, vector_idx);
+	nn_writeb(nn, ctrl_offset, entry->entry);
 
 	return 0;
 }
@@ -1706,7 +1709,7 @@ static int nfp_net_poll(struct napi_struct *napi, int budget)
 
 	if (pkts_polled < budget) {
 		napi_complete_done(napi, pkts_polled);
-		nfp_net_irq_unmask(r_vec->nfp_net, r_vec->irq_idx);
+		nfp_net_irq_unmask(r_vec->nfp_net, r_vec->irq_entry);
 	}
 
 	return pkts_polled;
@@ -1988,7 +1991,6 @@ static int
 nfp_net_prepare_vector(struct nfp_net *nn, struct nfp_net_r_vector *r_vec,
 		       int idx)
 {
-	struct msix_entry *entry = &nn->irq_entries[r_vec->irq_idx];
 	int err;
 
 	/* Setup NAPI */
@@ -1997,17 +1999,19 @@ nfp_net_prepare_vector(struct nfp_net *nn, struct nfp_net_r_vector *r_vec,
 
 	snprintf(r_vec->name, sizeof(r_vec->name),
 		 "%s-rxtx-%d", nn->netdev->name, idx);
-	err = request_irq(entry->vector, r_vec->handler, 0, r_vec->name, r_vec);
+	err = request_irq(r_vec->irq_vector, r_vec->handler, 0, r_vec->name,
+			  r_vec);
 	if (err) {
 		netif_napi_del(&r_vec->napi);
-		nn_err(nn, "Error requesting IRQ %d\n", entry->vector);
+		nn_err(nn, "Error requesting IRQ %d\n", r_vec->irq_vector);
 		return err;
 	}
-	disable_irq(entry->vector);
+	disable_irq(r_vec->irq_vector);
 
-	irq_set_affinity_hint(entry->vector, &r_vec->affinity_mask);
+	irq_set_affinity_hint(r_vec->irq_vector, &r_vec->affinity_mask);
 
-	nn_dbg(nn, "RV%02d: irq=%03d/%03d\n", idx, entry->vector, entry->entry);
+	nn_dbg(nn, "RV%02d: irq=%03d/%03d\n", idx, r_vec->irq_vector,
+	       r_vec->irq_entry);
 
 	return 0;
 }
@@ -2015,11 +2019,9 @@ nfp_net_prepare_vector(struct nfp_net *nn, struct nfp_net_r_vector *r_vec,
 static void
 nfp_net_cleanup_vector(struct nfp_net *nn, struct nfp_net_r_vector *r_vec)
 {
-	struct msix_entry *entry = &nn->irq_entries[r_vec->irq_idx];
-
-	irq_set_affinity_hint(entry->vector, NULL);
+	irq_set_affinity_hint(r_vec->irq_vector, NULL);
 	netif_napi_del(&r_vec->napi);
-	free_irq(entry->vector, r_vec);
+	free_irq(r_vec->irq_vector, r_vec);
 }
 
 /**
@@ -2148,7 +2150,7 @@ nfp_net_rx_ring_hw_cfg_write(struct nfp_net *nn,
 	/* Write the DMA address, size and MSI-X info to the device */
 	nn_writeq(nn, NFP_NET_CFG_RXR_ADDR(idx), rx_ring->dma);
 	nn_writeb(nn, NFP_NET_CFG_RXR_SZ(idx), ilog2(rx_ring->cnt));
-	nn_writeb(nn, NFP_NET_CFG_RXR_VEC(idx), rx_ring->r_vec->irq_idx);
+	nn_writeb(nn, NFP_NET_CFG_RXR_VEC(idx), rx_ring->r_vec->irq_entry);
 }
 
 static void
@@ -2157,7 +2159,7 @@ nfp_net_tx_ring_hw_cfg_write(struct nfp_net *nn,
 {
 	nn_writeq(nn, NFP_NET_CFG_TXR_ADDR(idx), tx_ring->dma);
 	nn_writeb(nn, NFP_NET_CFG_TXR_SZ(idx), ilog2(tx_ring->cnt));
-	nn_writeb(nn, NFP_NET_CFG_TXR_VEC(idx), tx_ring->r_vec->irq_idx);
+	nn_writeb(nn, NFP_NET_CFG_TXR_VEC(idx), tx_ring->r_vec->irq_entry);
 }
 
 static int __nfp_net_set_config_and_enable(struct nfp_net *nn)
@@ -2251,7 +2253,7 @@ static void nfp_net_open_stack(struct nfp_net *nn)
 
 	for (r = 0; r < nn->num_r_vecs; r++) {
 		napi_enable(&nn->r_vecs[r].napi);
-		enable_irq(nn->irq_entries[nn->r_vecs[r].irq_idx].vector);
+		enable_irq(nn->r_vecs[r].irq_vector);
 	}
 
 	netif_tx_wake_all_queues(nn->netdev);
@@ -2375,7 +2377,7 @@ static void nfp_net_close_stack(struct nfp_net *nn)
 	nn->link_up = false;
 
 	for (r = 0; r < nn->num_r_vecs; r++) {
-		disable_irq(nn->irq_entries[nn->r_vecs[r].irq_idx].vector);
+		disable_irq(nn->r_vecs[r].irq_vector);
 		napi_disable(&nn->r_vecs[r].napi);
 	}
 
@@ -3259,7 +3261,7 @@ int nfp_net_netdev_init(struct net_device *netdev)
 	netif_carrier_off(netdev);
 
 	nfp_net_set_ethtool_ops(netdev);
-	nfp_net_irqs_assign(netdev);
+	nfp_net_vecs_init(netdev);
 
 	return register_netdev(netdev);
 }