alx: prepare interrupt functions for multiple queues

Extend the interrupt bringup code and the interrupt handler for msi-x
interrupts in order to handle multiple queues.

We must change the poll function because with multiple queues it is possible
that an alx_napi structure has only a tx or only a rx queue pointer.

Based on the downstream driver at github.com/qca/alx

Signed-off-by: Tobias Regnery <tobias.regnery@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/drivers/net/ethernet/atheros/alx/main.c b/drivers/net/ethernet/atheros/alx/main.c
index a9fc44611b8a4ac590568037833fea2e3f1a6906..aeb42120910d7075d82df834feb561a1d36a5e9b 100644 (file)
--- a/drivers/net/ethernet/atheros/alx/main.c
+++ b/drivers/net/ethernet/atheros/alx/main.c
@@ -286,11 +286,13 @@ static int alx_poll(struct napi_struct *napi, int budget)
        struct alx_priv *alx = np->alx;
        struct alx_hw *hw = &alx->hw;
        unsigned long flags;
-       bool tx_complete;
-       int work;
+       bool tx_complete = true;
+       int work = 0;
 
-       tx_complete = alx_clean_tx_irq(np->txq);
-       work = alx_clean_rx_irq(np->rxq, budget);
+       if (np->txq)
+               tx_complete = alx_clean_tx_irq(np->txq);
+       if (np->rxq)
+               work = alx_clean_rx_irq(np->rxq, budget);
 
        if (!tx_complete || work == budget)
                return budget;
@@ -299,7 +301,7 @@ static int alx_poll(struct napi_struct *napi, int budget)
 
        /* enable interrupt */
        if (alx->flags & ALX_FLAG_USING_MSIX) {
-               alx_mask_msix(hw, 1, false);
+               alx_mask_msix(hw, np->vec_idx, false);
        } else {
                spin_lock_irqsave(&alx->irq_lock, flags);
                alx->int_mask |= ALX_ISR_TX_Q0 | ALX_ISR_RX_Q0;
@@ -372,9 +374,9 @@ static irqreturn_t alx_intr_msix_ring(int irq, void *data)
        struct alx_hw *hw = &np->alx->hw;
 
        /* mask interrupt to ACK chip */
-       alx_mask_msix(hw, 1, true);
+       alx_mask_msix(hw, np->vec_idx, true);
        /* clear interrupt status */
-       alx_write_mem32(hw, ALX_ISR, (ALX_ISR_TX_Q0 | ALX_ISR_RX_Q0));
+       alx_write_mem32(hw, ALX_ISR, np->vec_mask);
 
        napi_schedule(&np->napi);
 
@@ -678,6 +680,13 @@ static void alx_free_napis(struct alx_priv *alx)
        alx->qnapi[0] = NULL;
 }
 
+static const u32 tx_vect_mask[] = {ALX_ISR_TX_Q0, ALX_ISR_TX_Q1,
+                                  ALX_ISR_TX_Q2, ALX_ISR_TX_Q3};
+static const u32 rx_vect_mask[] = {ALX_ISR_RX_Q0, ALX_ISR_RX_Q1,
+                                  ALX_ISR_RX_Q2, ALX_ISR_RX_Q3,
+                                  ALX_ISR_RX_Q4, ALX_ISR_RX_Q5,
+                                  ALX_ISR_RX_Q6, ALX_ISR_RX_Q7};
+
 static int alx_alloc_napis(struct alx_priv *alx)
 {
        struct alx_napi *np;
@@ -685,7 +694,6 @@ static int alx_alloc_napis(struct alx_priv *alx)
        struct alx_tx_queue *txq;
 
        alx->int_mask &= ~ALX_ISR_ALL_QUEUES;
-       alx->int_mask |= ALX_ISR_TX_Q0 | ALX_ISR_RX_Q0;
 
        /* allocate alx_napi structures */
        np = kzalloc(sizeof(struct alx_napi), GFP_KERNEL);
@@ -703,9 +711,12 @@ static int alx_alloc_napis(struct alx_priv *alx)
                goto err_out;
 
        np->txq = txq;
+       txq->queue_idx = 0;
        txq->count = alx->tx_ringsz;
        txq->netdev = alx->dev;
        txq->dev = &alx->hw.pdev->dev;
+       np->vec_mask |= tx_vect_mask[0];
+       alx->int_mask |= tx_vect_mask[0];
 
        /* allocate rx queues */
        np = alx->qnapi[0];
@@ -715,9 +726,12 @@ static int alx_alloc_napis(struct alx_priv *alx)
 
        np->rxq = rxq;
        rxq->np = alx->qnapi[0];
+       rxq->queue_idx = 0;
        rxq->count = alx->rx_ringsz;
        rxq->netdev = alx->dev;
        rxq->dev = &alx->hw.pdev->dev;
+       np->vec_mask |= rx_vect_mask[0];
+       alx->int_mask |= rx_vect_mask[0];
 
        return 0;
 
@@ -727,24 +741,43 @@ err_out:
        return -ENOMEM;
 }
 
+static const int txq_vec_mapping_shift[] = {
+       0, ALX_MSI_MAP_TBL1_TXQ0_SHIFT,
+       0, ALX_MSI_MAP_TBL1_TXQ1_SHIFT,
+       1, ALX_MSI_MAP_TBL2_TXQ2_SHIFT,
+       1, ALX_MSI_MAP_TBL2_TXQ3_SHIFT,
+};
+
 static void alx_config_vector_mapping(struct alx_priv *alx)
 {
        struct alx_hw *hw = &alx->hw;
-       u32 tbl = 0;
+       u32 tbl[2] = {0, 0};
+       int i, vector, idx, shift;
 
        if (alx->flags & ALX_FLAG_USING_MSIX) {
-               tbl |= 1 << ALX_MSI_MAP_TBL1_TXQ0_SHIFT;
-               tbl |= 1 << ALX_MSI_MAP_TBL1_RXQ0_SHIFT;
+               /* tx mappings */
+               for (i = 0, vector = 1; i < alx->num_txq; i++, vector++) {
+                       idx = txq_vec_mapping_shift[i * 2];
+                       shift = txq_vec_mapping_shift[i * 2 + 1];
+                       tbl[idx] |= vector << shift;
+               }
+
+               /* rx mapping */
+               tbl[0] |= 1 << ALX_MSI_MAP_TBL1_RXQ0_SHIFT;
        }
 
-       alx_write_mem32(hw, ALX_MSI_MAP_TBL1, tbl);
-       alx_write_mem32(hw, ALX_MSI_MAP_TBL2, 0);
+       alx_write_mem32(hw, ALX_MSI_MAP_TBL1, tbl[0]);
+       alx_write_mem32(hw, ALX_MSI_MAP_TBL2, tbl[1]);
        alx_write_mem32(hw, ALX_MSI_ID_MAP, 0);
 }
 
 static bool alx_enable_msix(struct alx_priv *alx)
 {
-       int i, err, num_vec = 2;
+       int i, err, num_vec, num_txq, num_rxq;
+
+       num_txq = 1;
+       num_rxq = 1;
+       num_vec = max_t(int, num_txq, num_rxq) + 1;
 
        alx->msix_entries = kcalloc(num_vec, sizeof(struct msix_entry),
                                    GFP_KERNEL);
@@ -764,6 +797,10 @@ static bool alx_enable_msix(struct alx_priv *alx)
        }
 
        alx->num_vec = num_vec;
+       alx->num_napi = num_vec - 1;
+       alx->num_txq = num_txq;
+       alx->num_rxq = num_rxq;
+
        return true;
 }
 
@@ -771,21 +808,35 @@ static int alx_request_msix(struct alx_priv *alx)
 {
        struct net_device *netdev = alx->dev;
        int i, err, vector = 0, free_vector = 0;
-       struct alx_napi *np = alx->qnapi[0];
 
        err = request_irq(alx->msix_entries[0].vector, alx_intr_msix_misc,
                          0, netdev->name, alx);
        if (err)
                goto out_err;
 
-       vector++;
-       sprintf(np->irq_lbl, "%s-TxRx-0", netdev->name);
-
-       err = request_irq(alx->msix_entries[vector].vector,
-                         alx_intr_msix_ring, 0, np->irq_lbl, np);
+       for (i = 0; i < alx->num_napi; i++) {
+               struct alx_napi *np = alx->qnapi[i];
+
+               vector++;
+
+               if (np->txq && np->rxq)
+                       sprintf(np->irq_lbl, "%s-TxRx-%u", netdev->name,
+                               np->txq->queue_idx);
+               else if (np->txq)
+                       sprintf(np->irq_lbl, "%s-tx-%u", netdev->name,
+                               np->txq->queue_idx);
+               else if (np->rxq)
+                       sprintf(np->irq_lbl, "%s-rx-%u", netdev->name,
+                               np->rxq->queue_idx);
+               else
+                       sprintf(np->irq_lbl, "%s-unused", netdev->name);
+
+               np->vec_idx = vector;
+               err = request_irq(alx->msix_entries[vector].vector,
+                                 alx_intr_msix_ring, 0, np->irq_lbl, np);
                if (err)
                        goto out_free;
-
+       }
        return 0;
 
 out_free:
@@ -793,7 +844,8 @@ out_free:
 
        vector--;
        for (i = 0; i < vector; i++)
-               free_irq(alx->msix_entries[free_vector++].vector, alx->qnapi[0]);
+               free_irq(alx->msix_entries[free_vector++].vector,
+                        alx->qnapi[i]);
 
 out_err:
        return err;
@@ -808,6 +860,9 @@ static void alx_init_intr(struct alx_priv *alx, bool msix)
 
        if (!(alx->flags & ALX_FLAG_USING_MSIX)) {
                alx->num_vec = 1;
+               alx->num_napi = 1;
+               alx->num_txq = 1;
+               alx->num_rxq = 1;
 
                if (!pci_enable_msi(alx->hw.pdev))
                        alx->flags |= ALX_FLAG_USING_MSI;
@@ -863,6 +918,25 @@ static void alx_irq_disable(struct alx_priv *alx)
        }
 }
 
+static int alx_realloc_resources(struct alx_priv *alx)
+{
+       int err;
+
+       alx_free_rings(alx);
+       alx_free_napis(alx);
+       alx_disable_advanced_intr(alx);
+
+       err = alx_alloc_napis(alx);
+       if (err)
+               return err;
+
+       err = alx_alloc_rings(alx);
+       if (err)
+               return err;
+
+       return 0;
+}
+
 static int alx_request_irq(struct alx_priv *alx)
 {
        struct pci_dev *pdev = alx->hw.pdev;
@@ -879,8 +953,9 @@ static int alx_request_irq(struct alx_priv *alx)
                        goto out;
 
                /* msix request failed, realloc resources */
-               alx_disable_advanced_intr(alx);
-               alx_init_intr(alx, false);
+               err = alx_realloc_resources(alx);
+               if (err)
+                       goto out;
        }
 
        if (alx->flags & ALX_FLAG_USING_MSI) {
@@ -912,9 +987,10 @@ static void alx_free_irq(struct alx_priv *alx)
        int i, vector = 0;
 
        if (alx->flags & ALX_FLAG_USING_MSIX) {
-               /* we have only 2 vectors without multi queue support */
                free_irq(alx->msix_entries[vector++].vector, alx);
-               free_irq(alx->msix_entries[vector++].vector, alx->qnapi[0]);
+               for (i = 0; i < alx->num_napi; i++)
+                       free_irq(alx->msix_entries[vector++].vector,
+                                alx->qnapi[i]);
        } else {
                free_irq(pdev->irq, alx);
        }
@@ -1478,10 +1554,12 @@ static int alx_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
 static void alx_poll_controller(struct net_device *netdev)
 {
        struct alx_priv *alx = netdev_priv(netdev);
+       int i;
 
        if (alx->flags & ALX_FLAG_USING_MSIX) {
                alx_intr_msix_misc(0, alx);
-               alx_intr_msix_ring(0, alx->qnapi[0]);
+               for (i = 0; i < alx->num_txq; i++)
+                       alx_intr_msix_ring(0, alx->qnapi[i]);
        } else if (alx->flags & ALX_FLAG_USING_MSI)
                alx_intr_msi(0, alx);
        else