Spidernet RX Debugging printout

Add some debugging and error printing.

The show_rx_chain() prints out the status of the rx chain,
which shows that the status of the descriptors gets
messed up after the second & subsequent RX ramfulls.

Print out contents of bad packets if error occurs.

Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Cc: James K Lewis <jklewis@us.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 46 insertions, 0 deletions

diff --git a/drivers/net/spider_net.c b/drivers/net/spider_net.c
index 2239c16da543..d73018b5cfc8 100644
--- a/drivers/net/spider_net.c
+++ b/drivers/net/spider_net.c
@@ -961,6 +961,34 @@ spider_net_pass_skb_up(struct spider_net_descr *descr,
         card->netdev_stats.rx_bytes += skb->len;
 }
 
+#ifdef DEBUG
+static void show_rx_chain(struct spider_net_card *card)
+{
+        struct spider_net_descr_chain *chain = &card->rx_chain;
+        struct spider_net_descr *start= chain->tail;
+        struct spider_net_descr *descr= start;
+        int status;
+
+        int cnt = 0;
+        int cstat = spider_net_get_descr_status(descr);
+        printk(KERN_INFO "RX chain tail at descr=%ld\n",
+             (start - card->descr) - card->tx_chain.num_desc);
+        status = cstat;
+        do
+        {
+                status = spider_net_get_descr_status(descr);
+                if (cstat != status) {
+                        printk(KERN_INFO "Have %d descrs with stat=x%08x\n", cnt, cstat);
+                        cstat = status;
+                        cnt = 0;
+                }
+                cnt ++;
+                descr = descr->next;
+        } while (descr != start);
+        printk(KERN_INFO "Last %d descrs with stat=x%08x\n", cnt, cstat);
+}
+#endif
+
 /**
  * spider_net_decode_one_descr - processes an rx descriptor
  * @card: card structure
@@ -1021,6 +1049,24 @@ spider_net_decode_one_descr(struct spider_net_card *card)
                 goto bad_desc;
         }
 
+        if (descr->dmac_cmd_status & 0xfefe) {
+                pr_err("%s: bad status, cmd_status=x%08x\n",
+                               card->netdev->name,
+                               descr->dmac_cmd_status);
+                pr_err("buf_addr=x%08x\n", descr->buf_addr);
+                pr_err("buf_size=x%08x\n", descr->buf_size);
+                pr_err("next_descr_addr=x%08x\n", descr->next_descr_addr);
+                pr_err("result_size=x%08x\n", descr->result_size);
+                pr_err("valid_size=x%08x\n", descr->valid_size);
+                pr_err("data_status=x%08x\n", descr->data_status);
+                pr_err("data_error=x%08x\n", descr->data_error);
+                pr_err("bus_addr=x%08x\n", descr->bus_addr);
+                pr_err("which=%ld\n", descr - card->rx_chain.ring);
+
+                card->spider_stats.rx_desc_error++;
+                goto bad_desc;
+        }
+
         /* Ok, we've got a packet in descr */
         spider_net_pass_skb_up(descr, card);
         descr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;