spidernet: enhance the dump routine

Crazy device problems are hard to debug, when one does not have
good trace info. This patch makes a major enhancement to the
device dump routine.

Signed-off-by: Linas Vepstas <linas@austin.ibm.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

1 files changed, 70 insertions, 8 deletions

diff --git a/drivers/net/spider_net.c b/drivers/net/spider_net.c
index 4c8243a7f9c1..4d180072de4d 100644
--- a/drivers/net/spider_net.c
+++ b/drivers/net/spider_net.c
@@ -1022,34 +1022,94 @@ spider_net_pass_skb_up(struct spider_net_descr *descr,
         netif_receive_skb(skb);
 }
 
-#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;
+        struct spider_net_hw_descr *hwd = start->hwdescr;
+        struct device *dev = &card->netdev->dev;
+        u32 curr_desc, next_desc;
         int status;
 
+        int tot = 0;
         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);
+        int off = start - chain->ring;
+        int cstat = hwd->dmac_cmd_status;
+
+        dev_info(dev, "Total number of descrs=%d\n",
+                chain->num_desc);
+        dev_info(dev, "Chain tail located at descr=%d, status=0x%x\n",
+                off, cstat);
+
+        curr_desc = spider_net_read_reg(card, SPIDER_NET_GDACTDPA);
+        next_desc = spider_net_read_reg(card, SPIDER_NET_GDACNEXTDA);
+
         status = cstat;
         do
         {
-                status = spider_net_get_descr_status(descr);
+                hwd = descr->hwdescr;
+                off = descr - chain->ring;
+                status = hwd->dmac_cmd_status;
+
+                if (descr == chain->head)
+                        dev_info(dev, "Chain head is at %d, head status=0x%x\n",
+                                 off, status);
+
+                if (curr_desc == descr->bus_addr)
+                        dev_info(dev, "HW curr desc (GDACTDPA) is at %d, status=0x%x\n",
+                                 off, status);
+
+                if (next_desc == descr->bus_addr)
+                        dev_info(dev, "HW next desc (GDACNEXTDA) is at %d, status=0x%x\n",
+                                 off, status);
+
+                if (hwd->next_descr_addr == 0)
+                        dev_info(dev, "chain is cut at %d\n", off);
+
                 if (cstat != status) {
-                        printk(KERN_INFO "Have %d descrs with stat=x%08x\n", cnt, cstat);
+                        int from = (chain->num_desc + off - cnt) % chain->num_desc;
+                        int to = (chain->num_desc + off - 1) % chain->num_desc;
+                        dev_info(dev, "Have %d (from %d to %d) descrs "
+                                 "with stat=0x%08x\n", cnt, from, to, cstat);
                         cstat = status;
                         cnt = 0;
                 }
+
                 cnt ++;
+                tot ++;
+                descr = descr->next;
+        } while (descr != start);
+
+        dev_info(dev, "Last %d descrs with stat=0x%08x "
+                 "for a total of %d descrs\n", cnt, cstat, tot);
+
+#ifdef DEBUG
+        /* Now dump the whole ring */
+        descr = start;
+        do
+        {
+                struct spider_net_hw_descr *hwd = descr->hwdescr;
+                status = spider_net_get_descr_status(hwd);
+                cnt = descr - chain->ring;
+                dev_info(dev, "Descr %d stat=0x%08x skb=%p\n",
+                         cnt, status, descr->skb);
+                dev_info(dev, "bus addr=%08x buf addr=%08x sz=%d\n",
+                         descr->bus_addr, hwd->buf_addr, hwd->buf_size);
+                dev_info(dev, "next=%08x result sz=%d valid sz=%d\n",
+                         hwd->next_descr_addr, hwd->result_size,
+                         hwd->valid_size);
+                dev_info(dev, "dmac=%08x data stat=%08x data err=%08x\n",
+                         hwd->dmac_cmd_status, hwd->data_status,
+                         hwd->data_error);
+                dev_info(dev, "\n");
+
                 descr = descr->next;
         } while (descr != start);
-        printk(KERN_INFO "Last %d descrs with stat=x%08x\n", cnt, cstat);
-}
 #endif
 
+}
+
 /**
  * spider_net_resync_head_ptr - Advance head ptr past empty descrs
  *
@@ -1195,6 +1255,8 @@ spider_net_decode_one_descr(struct spider_net_card *card)
         return 1;
 
 bad_desc:
+        if (netif_msg_rx_err(card))
+                show_rx_chain(card);
         dev_kfree_skb_irq(descr->skb);
         descr->skb = NULL;
         hwdescr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;