[TG3]: Add msi support

Add MSI support for 5751 C0 and 5752.

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

2 files changed, 72 insertions, 5 deletions

diff --git a/drivers/net/tg3.c b/drivers/net/tg3.c
index fb3eb6f8a737..2a17af9bd1ce 100644
--- a/drivers/net/tg3.c
+++ b/drivers/net/tg3.c
@@ -2907,6 +2907,43 @@ static inline unsigned int tg3_has_work(struct net_device *dev, struct tg3 *tp)
         return work_exists;
 }
 
+/* MSI ISR - No need to check for interrupt sharing and no need to
+ * flush status block and interrupt mailbox. PCI ordering rules
+ * guarantee that MSI will arrive after the status block.
+ */
+static irqreturn_t tg3_msi(int irq, void *dev_id, struct pt_regs *regs)
+{
+        struct net_device *dev = dev_id;
+        struct tg3 *tp = netdev_priv(dev);
+        struct tg3_hw_status *sblk = tp->hw_status;
+        unsigned long flags;
+
+        spin_lock_irqsave(&tp->lock, flags);
+
+        /*
+         * writing any value to intr-mbox-0 clears PCI INTA# and
+         * chip-internal interrupt pending events.
+         * writing non-zero to intr-mbox-0 additional tells the
+         * NIC to stop sending us irqs, engaging "in-intr-handler"
+         * event coalescing.
+         */
+        tw32_mailbox(MAILBOX_INTERRUPT_0 + TG3_64BIT_REG_LOW, 0x00000001);
+        sblk->status &= ~SD_STATUS_UPDATED;
+
+        if (likely(tg3_has_work(dev, tp)))
+                netif_rx_schedule(dev);         /* schedule NAPI poll */
+        else {
+                /* no work, re-enable interrupts
+                 */
+                tw32_mailbox(MAILBOX_INTERRUPT_0 + TG3_64BIT_REG_LOW,
+                             0x00000000);
+        }
+
+        spin_unlock_irqrestore(&tp->lock, flags);
+
+        return IRQ_RETVAL(1);
+}
+
 static irqreturn_t tg3_interrupt(int irq, void *dev_id, struct pt_regs *regs)
 {
         struct net_device *dev = dev_id;
@@ -2965,7 +3002,9 @@ static int tg3_halt(struct tg3 *);
 #ifdef CONFIG_NET_POLL_CONTROLLER
 static void tg3_poll_controller(struct net_device *dev)
 {
-        tg3_interrupt(dev->irq, dev, NULL);
+        struct tg3 *tp = netdev_priv(dev);
+
+        tg3_interrupt(tp->pdev->irq, dev, NULL);
 }
 #endif
 
@@ -5778,10 +5817,29 @@ static int tg3_open(struct net_device *dev)
         if (err)
                 return err;
 
-        err = request_irq(dev->irq, tg3_interrupt,
-                          SA_SHIRQ, dev->name, dev);
+        if ((tp->tg3_flags2 & TG3_FLG2_5750_PLUS) &&
+            (GET_CHIP_REV(tp->pci_chip_rev_id) != CHIPREV_5750_AX) &&
+            (GET_CHIP_REV(tp->pci_chip_rev_id) != CHIPREV_5750_BX)) {
+                if (pci_enable_msi(tp->pdev) == 0) {
+                        u32 msi_mode;
+
+                        msi_mode = tr32(MSGINT_MODE);
+                        tw32(MSGINT_MODE, msi_mode | MSGINT_MODE_ENABLE);
+                        tp->tg3_flags2 |= TG3_FLG2_USING_MSI;
+                }
+        }
+        if (tp->tg3_flags2 & TG3_FLG2_USING_MSI)
+                err = request_irq(tp->pdev->irq, tg3_msi,
+                                  0, dev->name, dev);
+        else
+                err = request_irq(tp->pdev->irq, tg3_interrupt,
+                                  SA_SHIRQ, dev->name, dev);
 
         if (err) {
+                if (tp->tg3_flags2 & TG3_FLG2_USING_MSI) {
+                        pci_disable_msi(tp->pdev);
+                        tp->tg3_flags2 &= ~TG3_FLG2_USING_MSI;
+                }
                 tg3_free_consistent(tp);
                 return err;
         }
@@ -5811,7 +5869,11 @@ static int tg3_open(struct net_device *dev)
         spin_unlock_irq(&tp->lock);
 
         if (err) {
-                free_irq(dev->irq, dev);
+                free_irq(tp->pdev->irq, dev);
+                if (tp->tg3_flags2 & TG3_FLG2_USING_MSI) {
+                        pci_disable_msi(tp->pdev);
+                        tp->tg3_flags2 &= ~TG3_FLG2_USING_MSI;
+                }
                 tg3_free_consistent(tp);
                 return err;
         }
@@ -6086,7 +6148,11 @@ static int tg3_close(struct net_device *dev)
         spin_unlock(&tp->tx_lock);
         spin_unlock_irq(&tp->lock);
 
-        free_irq(dev->irq, dev);
+        free_irq(tp->pdev->irq, dev);
+        if (tp->tg3_flags2 & TG3_FLG2_USING_MSI) {
+                pci_disable_msi(tp->pdev);
+                tp->tg3_flags2 &= ~TG3_FLG2_USING_MSI;
+        }
 
         memcpy(&tp->net_stats_prev, tg3_get_stats(tp->dev),
                sizeof(tp->net_stats_prev));
diff --git a/drivers/net/tg3.h b/drivers/net/tg3.h
index d3f03f0f4c46..8de6f21037ba 100644
--- a/drivers/net/tg3.h
+++ b/drivers/net/tg3.h
@@ -2123,6 +2123,7 @@ struct tg3 {
 #define TG3_FLG2_5705_PLUS              0x00040000
 #define TG3_FLG2_5750_PLUS              0x00080000
 #define TG3_FLG2_PROTECTED_NVRAM        0x00100000
+#define TG3_FLG2_USING_MSI              0x00200000
 
         u32                             split_mode_max_reqs;
 #define SPLIT_MODE_5704_MAX_REQ         3