enic: bug fix: return notify intr credits

Return notify intr credits after notify intr from firmware.  This is
especially important for legacy PCI intr mode, where not returning
credits would cause PBA to remain asserted which would get us right
back into the ISR.

Signed-off-by: Scott Feldman <scofeldm@cisco.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/drivers/net/enic/enic.h b/drivers/net/enic/enic.h
index a832cc5..86b8c15 100644
--- a/drivers/net/enic/enic.h
+++ b/drivers/net/enic/enic.h
@@ -33,7 +33,7 @@
 
 #define DRV_NAME		"enic"
 #define DRV_DESCRIPTION		"Cisco 10G Ethernet Driver"
-#define DRV_VERSION		"1.0.0.648"
+#define DRV_VERSION		"1.0.0.933"
 #define DRV_COPYRIGHT		"Copyright 2008 Cisco Systems, Inc"
 #define PFX			DRV_NAME ": "
 
diff --git a/drivers/net/enic/enic_main.c b/drivers/net/enic/enic_main.c
index 5dd1156..e9bc79a 100644
--- a/drivers/net/enic/enic_main.c
+++ b/drivers/net/enic/enic_main.c
@@ -400,10 +400,13 @@
 		return IRQ_NONE;	/* not our interrupt */
 	}
 
-	if (ENIC_TEST_INTR(pba, ENIC_INTX_NOTIFY))
+	if (ENIC_TEST_INTR(pba, ENIC_INTX_NOTIFY)) {
+		vnic_intr_return_all_credits(&enic->intr[ENIC_INTX_NOTIFY]);
 		enic_notify_check(enic);
+	}
 
 	if (ENIC_TEST_INTR(pba, ENIC_INTX_ERR)) {
+		vnic_intr_return_all_credits(&enic->intr[ENIC_INTX_ERR]);
 		enic_log_q_error(enic);
 		/* schedule recovery from WQ/RQ error */
 		schedule_work(&enic->reset);
@@ -476,6 +479,8 @@
 {
 	struct enic *enic = data;
 
+	vnic_intr_return_all_credits(&enic->intr[ENIC_MSIX_ERR]);
+
 	enic_log_q_error(enic);
 
 	/* schedule recovery from WQ/RQ error */
@@ -488,8 +493,8 @@
 {
 	struct enic *enic = data;
 
+	vnic_intr_return_all_credits(&enic->intr[ENIC_MSIX_NOTIFY]);
 	enic_notify_check(enic);
-	vnic_intr_unmask(&enic->intr[ENIC_MSIX_NOTIFY]);
 
 	return IRQ_HANDLED;
 }
@@ -616,7 +621,7 @@
 			vlan_tag_insert, vlan_tag);
 }
 
-/* netif_tx_lock held, process context with BHs disabled */
+/* netif_tx_lock held, process context with BHs disabled, or BH */
 static int enic_hard_start_xmit(struct sk_buff *skb, struct net_device *netdev)
 {
 	struct enic *enic = netdev_priv(netdev);
@@ -1069,7 +1074,7 @@
 			lro_flush_all(&enic->lro_mgr);
 
 		napi_complete(napi);
-		vnic_intr_unmask(&enic->intr[ENIC_MSIX_RQ]);
+		vnic_intr_unmask(&enic->intr[ENIC_INTX_WQ_RQ]);
 	}
 
 	return rq_work_done;
@@ -1095,9 +1100,9 @@
 
 		vnic_rq_fill(&enic->rq[0], enic_rq_alloc_buf);
 
-		/* Accumulate intr event credits for this polling
+		/* Return intr event credits for this polling
 		 * cycle.  An intr event is the completion of a
-		 * a WQ or RQ packet.
+		 * RQ packet.
 		 */
 
 		vnic_intr_return_credits(&enic->intr[ENIC_MSIX_RQ],
diff --git a/drivers/net/enic/vnic_intr.h b/drivers/net/enic/vnic_intr.h
index ce633a5..9a53604 100644
--- a/drivers/net/enic/vnic_intr.h
+++ b/drivers/net/enic/vnic_intr.h
@@ -76,6 +76,20 @@
 	iowrite32(int_credit_return, &intr->ctrl->int_credit_return);
 }
 
+static inline unsigned int vnic_intr_credits(struct vnic_intr *intr)
+{
+	return ioread32(&intr->ctrl->int_credits);
+}
+
+static inline void vnic_intr_return_all_credits(struct vnic_intr *intr)
+{
+	unsigned int credits = vnic_intr_credits(intr);
+	int unmask = 1;
+	int reset_timer = 1;
+
+	vnic_intr_return_credits(intr, credits, unmask, reset_timer);
+}
+
 static inline u32 vnic_intr_legacy_pba(u32 __iomem *legacy_pba)
 {
 	/* read PBA without clearing */