pch_gbe: Fixed the issue on which a network freezes

The pch_gbe driver has an issue which a network stops,
when receiving traffic is high.
In the case, The link down and up are necessary to return a network.

This patch fixed this issue.

Signed-off-by: Toshiharu Okada <toshiharu-linux@dsn.okisemi.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 27 insertions, 29 deletions

diff --git a/drivers/net/pch_gbe/pch_gbe_main.c b/drivers/net/pch_gbe/pch_gbe_main.c
index 5474189d320b..b8b4ba27b0e7 100644
--- a/drivers/net/pch_gbe/pch_gbe_main.c
+++ b/drivers/net/pch_gbe/pch_gbe_main.c
@@ -1199,6 +1199,8 @@ static irqreturn_t pch_gbe_intr(int irq, void *data)
                         iowrite32((int_en & ~PCH_GBE_INT_RX_FIFO_ERR),
                                   &hw->reg->INT_EN);
                         pch_gbe_stop_receive(adapter);
+                        int_st |= ioread32(&hw->reg->INT_ST);
+                        int_st = int_st & ioread32(&hw->reg->INT_EN);
                 }
         if (int_st & PCH_GBE_INT_RX_DMA_ERR)
                 adapter->stats.intr_rx_dma_err_count++;
@@ -1218,14 +1220,11 @@ static irqreturn_t pch_gbe_intr(int irq, void *data)
                         /* Set Pause packet */
                         pch_gbe_mac_set_pause_packet(hw);
                 }
-                if ((int_en & (PCH_GBE_INT_RX_DMA_CMPLT | PCH_GBE_INT_TX_CMPLT))
-                    == 0) {
-                        return IRQ_HANDLED;
-                }
         }
 
         /* When request status is Receive interruption */
-        if ((int_st & (PCH_GBE_INT_RX_DMA_CMPLT | PCH_GBE_INT_TX_CMPLT))) {
+        if ((int_st & (PCH_GBE_INT_RX_DMA_CMPLT | PCH_GBE_INT_TX_CMPLT)) ||
+            (adapter->rx_stop_flag == true)) {
                 if (likely(napi_schedule_prep(&adapter->napi))) {
                         /* Enable only Rx Descriptor empty */
                         atomic_inc(&adapter->irq_sem);
@@ -1385,7 +1384,7 @@ pch_gbe_clean_tx(struct pch_gbe_adapter *adapter,
         struct sk_buff *skb;
         unsigned int i;
         unsigned int cleaned_count = 0;
-        bool cleaned = false;
+        bool cleaned = true;
 
         pr_debug("next_to_clean : %d\n", tx_ring->next_to_clean);
 
@@ -1396,7 +1395,6 @@ pch_gbe_clean_tx(struct pch_gbe_adapter *adapter,
 
         while ((tx_desc->gbec_status & DSC_INIT16) == 0x0000) {
                 pr_debug("gbec_status:0x%04x\n", tx_desc->gbec_status);
-                cleaned = true;
                 buffer_info = &tx_ring->buffer_info[i];
                 skb = buffer_info->skb;
 
@@ -1439,8 +1437,10 @@ pch_gbe_clean_tx(struct pch_gbe_adapter *adapter,
                 tx_desc = PCH_GBE_TX_DESC(*tx_ring, i);
 
                 /* weight of a sort for tx, to avoid endless transmit cleanup */
-                if (cleaned_count++ == PCH_GBE_TX_WEIGHT)
+                if (cleaned_count++ == PCH_GBE_TX_WEIGHT) {
+                        cleaned = false;
                         break;
+                }
         }
         pr_debug("called pch_gbe_unmap_and_free_tx_resource() %d count\n",
                  cleaned_count);
@@ -2168,7 +2168,6 @@ static int pch_gbe_napi_poll(struct napi_struct *napi, int budget)
 {
         struct pch_gbe_adapter *adapter =
             container_of(napi, struct pch_gbe_adapter, napi);
-        struct net_device *netdev = adapter->netdev;
         int work_done = 0;
         bool poll_end_flag = false;
         bool cleaned = false;
@@ -2176,33 +2175,32 @@ static int pch_gbe_napi_poll(struct napi_struct *napi, int budget)
 
         pr_debug("budget : %d\n", budget);
 
-        /* Keep link state information with original netdev */
-        if (!netif_carrier_ok(netdev)) {
+        pch_gbe_clean_rx(adapter, adapter->rx_ring, &work_done, budget);
+        cleaned = pch_gbe_clean_tx(adapter, adapter->tx_ring);
+
+        if (!cleaned)
+                work_done = budget;
+        /* If no Tx and not enough Rx work done,
+         * exit the polling mode
+         */
+        if (work_done < budget)
                 poll_end_flag = true;
-        } else {
-                pch_gbe_clean_rx(adapter, adapter->rx_ring, &work_done, budget);
+
+        if (poll_end_flag) {
+                napi_complete(napi);
+                if (adapter->rx_stop_flag) {
+                        adapter->rx_stop_flag = false;
+                        pch_gbe_start_receive(&adapter->hw);
+                }
+                pch_gbe_irq_enable(adapter);
+        } else
                 if (adapter->rx_stop_flag) {
                         adapter->rx_stop_flag = false;
                         pch_gbe_start_receive(&adapter->hw);
                         int_en = ioread32(&adapter->hw.reg->INT_EN);
                         iowrite32((int_en | PCH_GBE_INT_RX_FIFO_ERR),
-                                        &adapter->hw.reg->INT_EN);
+                                &adapter->hw.reg->INT_EN);
                 }
-                cleaned = pch_gbe_clean_tx(adapter, adapter->tx_ring);
-
-                if (cleaned)
-                        work_done = budget;
-                /* If no Tx and not enough Rx work done,
-                 * exit the polling mode
-                 */
-                if (work_done < budget)
-                        poll_end_flag = true;
-        }
-
-        if (poll_end_flag) {
-                napi_complete(napi);
-                pch_gbe_irq_enable(adapter);
-        }
 
         pr_debug("poll_end_flag : %d  work_done : %d  budget : %d\n",
                  poll_end_flag, work_done, budget);