forcedeth: remove msix + napi

This patch removes support for msix running in conjunction with napi.
There has been reported issues regarding the behaviour of irqmask and
generation of interrupts by the HW when in MSIX mode. When running napi,
the driver is constantly turning off/on the irqmask. For the time being,
I am going to disable it until I can root cause the issue.
Signed-off-by: Ayaz Abdulla <aabdulla@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/forcedeth.c

@@ -3731,26 +3731,6 @@ static int nv_napi_poll(struct napi_struct *napi, int budget)
 }
 #endif
 
-#ifdef CONFIG_FORCEDETH_NAPI
-static irqreturn_t nv_nic_irq_rx(int foo, void *data)
-{
-	struct net_device *dev = (struct net_device *) data;
-	struct fe_priv *np = netdev_priv(dev);
-	u8 __iomem *base = get_hwbase(dev);
-	u32 events;
-
-	events = readl(base + NvRegMSIXIrqStatus) & NVREG_IRQ_RX_ALL;
-
-	if (events) {
-		/* disable receive interrupts on the nic */
-		writel(NVREG_IRQ_RX_ALL, base + NvRegIrqMask);
-		pci_push(base);
-		writel(NVREG_IRQ_RX_ALL, base + NvRegMSIXIrqStatus);
-		napi_schedule(&np->napi);
-	}
-	return IRQ_HANDLED;
-}
-#else
 static irqreturn_t nv_nic_irq_rx(int foo, void *data)
 {
 	struct net_device *dev = (struct net_device *) data;
@@ -3797,7 +3777,6 @@ static irqreturn_t nv_nic_irq_rx(int foo, void *data)
 
 	return IRQ_RETVAL(i);
 }
-#endif
 
 static irqreturn_t nv_nic_irq_other(int foo, void *data)
 {
@@ -5670,7 +5649,12 @@ static int __devinit nv_probe(struct pci_dev *pci_dev, const struct pci_device_i
 		np->msi_flags |= NV_MSI_CAPABLE;
 	}
 	if ((id->driver_data & DEV_HAS_MSI_X) && msix) {
+		/* msix has had reported issues when modifying irqmask
+		   as in the case of napi, therefore, disable for now
+		*/
+#ifndef CONFIG_FORCEDETH_NAPI
 		np->msi_flags |= NV_MSI_X_CAPABLE;
+#endif
 	}
 
 	np->pause_flags = NV_PAUSEFRAME_RX_CAPABLE | NV_PAUSEFRAME_RX_REQ | NV_PAUSEFRAME_AUTONEG;