[PATCH] e1000: made loopback test robust

Added enhanced functionality to the loopback diags to wrap the descriptor rings.

Signed-off-by: Mallikarjuna R Chilakala <mallikarjuna.chilakala@intel.com>
Signed-off-by: Ganesh Venkatesan <ganesh.venkatesan@intel.com>
Signed-off-by: John Ronciak <john.ronciak@intel.com>
diff -up net-drivers-2.6/drivers/net/e1000/e1000_ethtool.c net-drivers-2.6/drivers/net/e1000.new/e1000_ethtool.c

1 files changed, 58 insertions, 23 deletions

diff --git a/drivers/net/e1000/e1000_ethtool.c b/drivers/net/e1000/e1000_ethtool.c
index 0a2ca7c73a41..fae585453463 100644
--- a/drivers/net/e1000/e1000_ethtool.c
+++ b/drivers/net/e1000/e1000_ethtool.c
@@ -919,7 +919,8 @@ e1000_setup_desc_rings(struct e1000_adapter *adapter)
 
         /* Setup Tx descriptor ring and Tx buffers */
 
-        txdr->count = 80;
+        if(!txdr->count)
+                txdr->count = E1000_DEFAULT_TXD;   
 
         size = txdr->count * sizeof(struct e1000_buffer);
         if(!(txdr->buffer_info = kmalloc(size, GFP_KERNEL))) {
@@ -974,7 +975,8 @@ e1000_setup_desc_rings(struct e1000_adapter *adapter)
 
         /* Setup Rx descriptor ring and Rx buffers */
 
-        rxdr->count = 80;
+        if(!rxdr->count)
+                rxdr->count = E1000_DEFAULT_RXD;   
 
         size = rxdr->count * sizeof(struct e1000_buffer);
         if(!(rxdr->buffer_info = kmalloc(size, GFP_KERNEL))) {
@@ -1310,31 +1312,62 @@ e1000_run_loopback_test(struct e1000_adapter *adapter)
         struct e1000_desc_ring *txdr = &adapter->test_tx_ring;
         struct e1000_desc_ring *rxdr = &adapter->test_rx_ring;
         struct pci_dev *pdev = adapter->pdev;
-        int i, ret_val;
+        int i, j, k, l, lc, good_cnt, ret_val=0;
+        unsigned long time;
 
         E1000_WRITE_REG(&adapter->hw, RDT, rxdr->count - 1);
 
-        for(i = 0; i < 64; i++) {
-                e1000_create_lbtest_frame(txdr->buffer_info[i].skb, 1024);
-                pci_dma_sync_single_for_device(pdev, txdr->buffer_info[i].dma,
-                                            txdr->buffer_info[i].length,
-                                            PCI_DMA_TODEVICE);
-        }
-        E1000_WRITE_REG(&adapter->hw, TDT, i);
-
-        msec_delay(200);
-
-        i = 0;
-        do {
-                pci_dma_sync_single_for_cpu(pdev, rxdr->buffer_info[i].dma,
-                                            rxdr->buffer_info[i].length,
-                                            PCI_DMA_FROMDEVICE);
-
-                ret_val = e1000_check_lbtest_frame(rxdr->buffer_info[i].skb,
-                                                   1024);
-                i++;
-        } while (ret_val != 0 && i < 64);
+        /* Calculate the loop count based on the largest descriptor ring 
+         * The idea is to wrap the largest ring a number of times using 64
+         * send/receive pairs during each loop
+         */
 
+        if(rxdr->count <= txdr->count)
+                lc = ((txdr->count / 64) * 2) + 1;
+        else
+                lc = ((rxdr->count / 64) * 2) + 1;
+
+        k = l = 0;
+        for(j = 0; j <= lc; j++) { /* loop count loop */
+                for(i = 0; i < 64; i++) { /* send the packets */
+                        e1000_create_lbtest_frame(txdr->buffer_info[i].skb, 
+                                        1024);
+                        pci_dma_sync_single_for_device(pdev, 
+                                        txdr->buffer_info[k].dma,
+                                        txdr->buffer_info[k].length,
+                                        PCI_DMA_TODEVICE);
+                        if(unlikely(++k == txdr->count)) k = 0;
+                }
+                E1000_WRITE_REG(&adapter->hw, TDT, k);
+                msec_delay(200);
+                time = jiffies; /* set the start time for the receive */
+                good_cnt = 0;
+                do { /* receive the sent packets */
+                        pci_dma_sync_single_for_cpu(pdev, 
+                                        rxdr->buffer_info[l].dma,
+                                        rxdr->buffer_info[l].length,
+                                        PCI_DMA_FROMDEVICE);
+        
+                        ret_val = e1000_check_lbtest_frame(
+                                        rxdr->buffer_info[l].skb,
+                                        1024);
+                        if(!ret_val)
+                                good_cnt++;
+                        if(unlikely(++l == rxdr->count)) l = 0;
+                        /* time + 20 msecs (200 msecs on 2.4) is more than 
+                         * enough time to complete the receives, if it's 
+                         * exceeded, break and error off
+                         */
+                } while (good_cnt < 64 && jiffies < (time + 20));
+                if(good_cnt != 64) {
+                        ret_val = 13; /* ret_val is the same as mis-compare */
+                        break; 
+                }
+                if(jiffies >= (time + 2)) {
+                        ret_val = 14; /* error code for time out error */
+                        break;
+                }
+        } /* end loop count loop */
         return ret_val;
 }
 
@@ -1371,6 +1404,8 @@ e1000_link_test(struct e1000_adapter *adapter, uint64_t *data)
                 *data = 1; 
         } else {
                 e1000_check_for_link(&adapter->hw);
+                if(adapter->hw.autoneg)  /* if auto_neg is set wait for it */
+                        msec_delay(4000);
 
                 if(!(E1000_READ_REG(&adapter->hw, STATUS) & E1000_STATUS_LU)) {
                         *data = 1;