[BNX2]: Add 1-shot MSI handler for 5709.

The 5709 supports the one-shot MSI handler similar to some of the tg3
chips.  In this mode, the MSI disables itself automatically until it
is re-enabled at the end of NAPI poll.

Put the request_irq/free_irq logic in common procedures.

Signed-off-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

2 files changed, 81 insertions, 41 deletions

diff --git a/drivers/net/bnx2.c b/drivers/net/bnx2.c
index f072028e3e3b..97ed4006a345 100644
--- a/drivers/net/bnx2.c
+++ b/drivers/net/bnx2.c
@@ -2262,6 +2262,23 @@ bnx2_msi(int irq, void *dev_instance)
 }
 
 static irqreturn_t
+bnx2_msi_1shot(int irq, void *dev_instance)
+{
+        struct net_device *dev = dev_instance;
+        struct bnx2 *bp = netdev_priv(dev);
+
+        prefetch(bp->status_blk);
+
+        /* Return here if interrupt is disabled. */
+        if (unlikely(atomic_read(&bp->intr_sem) != 0))
+                return IRQ_HANDLED;
+
+        netif_rx_schedule(dev);
+
+        return IRQ_HANDLED;
+}
+
+static irqreturn_t
 bnx2_interrupt(int irq, void *dev_instance)
 {
         struct net_device *dev = dev_instance;
@@ -3759,13 +3776,17 @@ bnx2_init_chip(struct bnx2 *bp)
         REG_WR(bp, BNX2_HC_STAT_COLLECT_TICKS, 0xbb8);  /* 3ms */
 
         if (CHIP_ID(bp) == CHIP_ID_5706_A1)
-                REG_WR(bp, BNX2_HC_CONFIG, BNX2_HC_CONFIG_COLLECT_STATS);
+                val = BNX2_HC_CONFIG_COLLECT_STATS;
         else {
-                REG_WR(bp, BNX2_HC_CONFIG, BNX2_HC_CONFIG_RX_TMR_MODE |
-                       BNX2_HC_CONFIG_TX_TMR_MODE |
-                       BNX2_HC_CONFIG_COLLECT_STATS);
+                val = BNX2_HC_CONFIG_RX_TMR_MODE | BNX2_HC_CONFIG_TX_TMR_MODE |
+                      BNX2_HC_CONFIG_COLLECT_STATS;
         }
 
+        if (bp->flags & ONE_SHOT_MSI_FLAG)
+                val |= BNX2_HC_CONFIG_ONE_SHOT;
+
+        REG_WR(bp, BNX2_HC_CONFIG, val);
+
         /* Clear internal stats counters. */
         REG_WR(bp, BNX2_HC_COMMAND, BNX2_HC_COMMAND_CLR_STAT_NOW);
 
@@ -4610,6 +4631,38 @@ bnx2_restart_timer:
         mod_timer(&bp->timer, jiffies + bp->current_interval);
 }
 
+static int
+bnx2_request_irq(struct bnx2 *bp)
+{
+        struct net_device *dev = bp->dev;
+        int rc = 0;
+
+        if (bp->flags & USING_MSI_FLAG) {
+                irq_handler_t   fn = bnx2_msi;
+
+                if (bp->flags & ONE_SHOT_MSI_FLAG)
+                        fn = bnx2_msi_1shot;
+
+                rc = request_irq(bp->pdev->irq, fn, 0, dev->name, dev);
+        } else
+                rc = request_irq(bp->pdev->irq, bnx2_interrupt,
+                                 IRQF_SHARED, dev->name, dev);
+        return rc;
+}
+
+static void
+bnx2_free_irq(struct bnx2 *bp)
+{
+        struct net_device *dev = bp->dev;
+
+        if (bp->flags & USING_MSI_FLAG) {
+                free_irq(bp->pdev->irq, dev);
+                pci_disable_msi(bp->pdev);
+                bp->flags &= ~(USING_MSI_FLAG | ONE_SHOT_MSI_FLAG);
+        } else
+                free_irq(bp->pdev->irq, dev);
+}
+
 /* Called with rtnl_lock */
 static int
 bnx2_open(struct net_device *dev)
@@ -4626,24 +4679,15 @@ bnx2_open(struct net_device *dev)
         if (rc)
                 return rc;
 
-        if ((CHIP_ID(bp) != CHIP_ID_5706_A0) &&
-                (CHIP_ID(bp) != CHIP_ID_5706_A1) &&
-                !disable_msi) {
-
+        if ((bp->flags & MSI_CAP_FLAG) && !disable_msi) {
                 if (pci_enable_msi(bp->pdev) == 0) {
                         bp->flags |= USING_MSI_FLAG;
-                        rc = request_irq(bp->pdev->irq, bnx2_msi, 0, dev->name,
-                                        dev);
+                        if (CHIP_NUM(bp) == CHIP_NUM_5709)
+                                bp->flags |= ONE_SHOT_MSI_FLAG;
                 }
-                else {
-                        rc = request_irq(bp->pdev->irq, bnx2_interrupt,
-                                        IRQF_SHARED, dev->name, dev);
-                }
-        }
-        else {
-                rc = request_irq(bp->pdev->irq, bnx2_interrupt, IRQF_SHARED,
-                                dev->name, dev);
         }
+        rc = bnx2_request_irq(bp);
+
         if (rc) {
                 bnx2_free_mem(bp);
                 return rc;
@@ -4652,11 +4696,7 @@ bnx2_open(struct net_device *dev)
         rc = bnx2_init_nic(bp);
 
         if (rc) {
-                free_irq(bp->pdev->irq, dev);
-                if (bp->flags & USING_MSI_FLAG) {
-                        pci_disable_msi(bp->pdev);
-                        bp->flags &= ~USING_MSI_FLAG;
-                }
+                bnx2_free_irq(bp);
                 bnx2_free_skbs(bp);
                 bnx2_free_mem(bp);
                 return rc;
@@ -4680,16 +4720,13 @@ bnx2_open(struct net_device *dev)
                                bp->dev->name);
 
                         bnx2_disable_int(bp);
-                        free_irq(bp->pdev->irq, dev);
-                        pci_disable_msi(bp->pdev);
-                        bp->flags &= ~USING_MSI_FLAG;
+                        bnx2_free_irq(bp);
 
                         rc = bnx2_init_nic(bp);
 
-                        if (!rc) {
-                                rc = request_irq(bp->pdev->irq, bnx2_interrupt,
-                                        IRQF_SHARED, dev->name, dev);
-                        }
+                        if (!rc)
+                                rc = bnx2_request_irq(bp);
+
                         if (rc) {
                                 bnx2_free_skbs(bp);
                                 bnx2_free_mem(bp);
@@ -4927,11 +4964,7 @@ bnx2_close(struct net_device *dev)
         else
                 reset_code = BNX2_DRV_MSG_CODE_SUSPEND_NO_WOL;
         bnx2_reset_chip(bp, reset_code);
-        free_irq(bp->pdev->irq, dev);
-        if (bp->flags & USING_MSI_FLAG) {
-                pci_disable_msi(bp->pdev);
-                bp->flags &= ~USING_MSI_FLAG;
-        }
+        bnx2_free_irq(bp);
         bnx2_free_skbs(bp);
         bnx2_free_mem(bp);
         bp->link_up = 0;
@@ -6095,6 +6128,11 @@ bnx2_init_board(struct pci_dev *pdev, struct net_device *dev)
                 }
         }
 
+        if (CHIP_ID(bp) != CHIP_ID_5706_A0 && CHIP_ID(bp) != CHIP_ID_5706_A1) {
+                if (pci_find_capability(pdev, PCI_CAP_ID_MSI))
+                        bp->flags |= MSI_CAP_FLAG;
+        }
+
         /* 5708 cannot support DMA addresses > 40-bit.  */
         if (CHIP_NUM(bp) == CHIP_NUM_5708)
                 persist_dma_mask = dma_mask = DMA_40BIT_MASK;
diff --git a/drivers/net/bnx2.h b/drivers/net/bnx2.h
index ba175a800c8e..121576d144d0 100644
--- a/drivers/net/bnx2.h
+++ b/drivers/net/bnx2.h
@@ -6468,12 +6468,14 @@ struct bnx2 {
         u32                     last_status_idx;
 
         u32                     flags;
-#define PCIX_FLAG                       1
-#define PCI_32BIT_FLAG                  2
-#define ONE_TDMA_FLAG                   4       /* no longer used */
-#define NO_WOL_FLAG                     8
-#define USING_MSI_FLAG                  0x20
-#define ASF_ENABLE_FLAG                 0x40
+#define PCIX_FLAG                       0x00000001
+#define PCI_32BIT_FLAG                  0x00000002
+#define ONE_TDMA_FLAG                   0x00000004      /* no longer used */
+#define NO_WOL_FLAG                     0x00000008
+#define USING_MSI_FLAG                  0x00000020
+#define ASF_ENABLE_FLAG                 0x00000040
+#define MSI_CAP_FLAG                    0x00000080
+#define ONE_SHOT_MSI_FLAG               0x00000100
 
         /* Put tx producer and consumer fields in separate cache lines. */