pch_gbe: add extra clean tx
authorAndy Cress <andycress@gmail.com>
Thu, 26 Jul 2012 06:00:11 +0000 (06:00 +0000)
committerDavid S. Miller <davem@davemloft.net>
Thu, 26 Jul 2012 21:30:23 +0000 (14:30 -0700)
This adds extra cleaning to the pch_gbe_clean_tx routine to avoid
transmit timeouts on some BCM PHYs that have different timing.
Also update the DRV_VERSION to 1.01, and show it.

Signed-off-by: Andy Cress <andy.cress@us.kontron.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c

index 99bba29e0553dcba262eb69b9c7c2f378bb5fee0..1bb4cd14b149564a0de629c83a66065e98f47f8f 100644 (file)
@@ -26,7 +26,7 @@
 #include <linux/ptp_classify.h>
 #endif
 
-#define DRV_VERSION     "1.00"
+#define DRV_VERSION     "1.01"
 const char pch_driver_version[] = DRV_VERSION;
 
 #define PCI_DEVICE_ID_INTEL_IOH1_GBE   0x8802          /* Pci device ID */
@@ -1579,7 +1579,8 @@ pch_gbe_clean_tx(struct pch_gbe_adapter *adapter,
        struct sk_buff *skb;
        unsigned int i;
        unsigned int cleaned_count = 0;
-       bool cleaned = true;
+       bool cleaned = false;
+       int unused, thresh;
 
        pr_debug("next_to_clean : %d\n", tx_ring->next_to_clean);
 
@@ -1588,10 +1589,36 @@ pch_gbe_clean_tx(struct pch_gbe_adapter *adapter,
        pr_debug("gbec_status:0x%04x  dma_status:0x%04x\n",
                 tx_desc->gbec_status, tx_desc->dma_status);
 
+       unused = PCH_GBE_DESC_UNUSED(tx_ring);
+       thresh = tx_ring->count - PCH_GBE_TX_WEIGHT;
+       if ((tx_desc->gbec_status == DSC_INIT16) && (unused < thresh))
+       {  /* current marked clean, tx queue filling up, do extra clean */
+               int j, k;
+               if (unused < 8) {  /* tx queue nearly full */
+                       pr_debug("clean_tx: transmit queue warning (%x,%x) unused=%d\n",
+                               tx_ring->next_to_clean,tx_ring->next_to_use,unused);
+               }
+
+               /* current marked clean, scan for more that need cleaning. */
+               k = i;
+               for (j = 0; j < PCH_GBE_TX_WEIGHT; j++)
+               {
+                       tx_desc = PCH_GBE_TX_DESC(*tx_ring, k);
+                       if (tx_desc->gbec_status != DSC_INIT16) break; /*found*/
+                       if (++k >= tx_ring->count) k = 0;  /*increment, wrap*/
+               }
+               if (j < PCH_GBE_TX_WEIGHT) {
+                       pr_debug("clean_tx: unused=%d loops=%d found tx_desc[%x,%x:%x].gbec_status=%04x\n",
+                               unused,j, i,k, tx_ring->next_to_use, tx_desc->gbec_status);
+                       i = k;  /*found one to clean, usu gbec_status==2000.*/
+               }
+       }
+
        while ((tx_desc->gbec_status & DSC_INIT16) == 0x0000) {
                pr_debug("gbec_status:0x%04x\n", tx_desc->gbec_status);
                buffer_info = &tx_ring->buffer_info[i];
                skb = buffer_info->skb;
+               cleaned = true;
 
                if ((tx_desc->gbec_status & PCH_GBE_TXD_GMAC_STAT_ABT)) {
                        adapter->stats.tx_aborted_errors++;
@@ -1639,18 +1666,21 @@ pch_gbe_clean_tx(struct pch_gbe_adapter *adapter,
        }
        pr_debug("called pch_gbe_unmap_and_free_tx_resource() %d count\n",
                 cleaned_count);
-       /* Recover from running out of Tx resources in xmit_frame */
-       spin_lock(&tx_ring->tx_lock);
-       if (unlikely(cleaned && (netif_queue_stopped(adapter->netdev)))) {
-               netif_wake_queue(adapter->netdev);
-               adapter->stats.tx_restart_count++;
-               pr_debug("Tx wake queue\n");
-       }
+       if (cleaned_count > 0)  { /*skip this if nothing cleaned*/
+               /* Recover from running out of Tx resources in xmit_frame */
+               spin_lock(&tx_ring->tx_lock);
+               if (unlikely(cleaned && (netif_queue_stopped(adapter->netdev))))
+               {
+                       netif_wake_queue(adapter->netdev);
+                       adapter->stats.tx_restart_count++;
+                       pr_debug("Tx wake queue\n");
+               }
 
-       tx_ring->next_to_clean = i;
+               tx_ring->next_to_clean = i;
 
-       pr_debug("next_to_clean : %d\n", tx_ring->next_to_clean);
-       spin_unlock(&tx_ring->tx_lock);
+               pr_debug("next_to_clean : %d\n", tx_ring->next_to_clean);
+               spin_unlock(&tx_ring->tx_lock);
+       }
        return cleaned;
 }
 
@@ -2389,7 +2419,7 @@ static int pch_gbe_napi_poll(struct napi_struct *napi, int budget)
        pch_gbe_clean_rx(adapter, adapter->rx_ring, &work_done, budget);
        cleaned = pch_gbe_clean_tx(adapter, adapter->tx_ring);
 
-       if (!cleaned)
+       if (cleaned)
                work_done = budget;
        /* If no Tx and not enough Rx work done,
         * exit the polling mode
@@ -2795,6 +2825,7 @@ static int __init pch_gbe_init_module(void)
 {
        int ret;
 
+       pr_info("EG20T PCH Gigabit Ethernet Driver - version %s\n",DRV_VERSION);
        ret = pci_register_driver(&pch_gbe_driver);
        if (copybreak != PCH_GBE_COPYBREAK_DEFAULT) {
                if (copybreak == 0) {