fedora core 6 1.2949 + vserver 2.2.0
[linux-2.6.git] / drivers / net / spider_net.c
index 1f5975a..8ea2fc1 100644 (file)
@@ -21,7 +21,6 @@
  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
-#include <linux/config.h>
 #include <linux/compiler.h>
 #include <linux/crc32.h>
 #include <linux/delay.h>
@@ -56,12 +55,13 @@ MODULE_AUTHOR("Utz Bacher <utz.bacher@de.ibm.com> and Jens Osterkamp " \
              "<Jens.Osterkamp@de.ibm.com>");
 MODULE_DESCRIPTION("Spider Southbridge Gigabit Ethernet driver");
 MODULE_LICENSE("GPL");
+MODULE_VERSION(VERSION);
 
 static int rx_descriptors = SPIDER_NET_RX_DESCRIPTORS_DEFAULT;
 static int tx_descriptors = SPIDER_NET_TX_DESCRIPTORS_DEFAULT;
 
-module_param(rx_descriptors, int, 0644);
-module_param(tx_descriptors, int, 0644);
+module_param(rx_descriptors, int, 0444);
+module_param(tx_descriptors, int, 0444);
 
 MODULE_PARM_DESC(rx_descriptors, "number of descriptors used " \
                 "in rx chains");
@@ -85,15 +85,14 @@ MODULE_DEVICE_TABLE(pci, spider_net_pci_tbl);
  *
  * returns the content of the specified SMMIO register.
  */
-static u32
+static inline u32
 spider_net_read_reg(struct spider_net_card *card, u32 reg)
 {
-       u32 value;
-
-       value = readl(card->regs + reg);
-       value = le32_to_cpu(value);
-
-       return value;
+       /* We use the powerpc specific variants instead of readl_be() because
+        * we know spidernet is not a real PCI device and we can thus avoid the
+        * performance hit caused by the PCI workarounds.
+        */
+       return in_be32(card->regs + reg);
 }
 
 /**
@@ -102,11 +101,14 @@ spider_net_read_reg(struct spider_net_card *card, u32 reg)
  * @reg: register to write to
  * @value: value to write into the specified SMMIO register
  */
-static void
+static inline void
 spider_net_write_reg(struct spider_net_card *card, u32 reg, u32 value)
 {
-       value = cpu_to_le32(value);
-       writel(value, card->regs + reg);
+       /* We use the powerpc specific variants instead of writel_be() because
+        * we know spidernet is not a real PCI device and we can thus avoid the
+        * performance hit caused by the PCI workarounds.
+        */
+       out_be32(card->regs + reg, value);
 }
 
 /** spider_net_write_phy - write to phy register
@@ -260,39 +262,10 @@ spider_net_get_mac_address(struct net_device *netdev)
  *
  * returns the status as in the dmac_cmd_status field of the descriptor
  */
-static enum spider_net_descr_status
+static inline int
 spider_net_get_descr_status(struct spider_net_descr *descr)
 {
-       u32 cmd_status;
-
-       cmd_status = descr->dmac_cmd_status;
-       cmd_status >>= SPIDER_NET_DESCR_IND_PROC_SHIFT;
-       /* no need to mask out any bits, as cmd_status is 32 bits wide only
-        * (and unsigned) */
-       return cmd_status;
-}
-
-/**
- * spider_net_set_descr_status -- sets the status of a descriptor
- * @descr: descriptor to change
- * @status: status to set in the descriptor
- *
- * changes the status to the specified value. Doesn't change other bits
- * in the status
- */
-static void
-spider_net_set_descr_status(struct spider_net_descr *descr,
-                           enum spider_net_descr_status status)
-{
-       u32 cmd_status;
-       /* read the status */
-       cmd_status = descr->dmac_cmd_status;
-       /* clean the upper 4 bits */
-       cmd_status &= SPIDER_NET_DESCR_IND_PROC_MASKO;
-       /* add the status to it */
-       cmd_status |= ((u32)status)<<SPIDER_NET_DESCR_IND_PROC_SHIFT;
-       /* and write it back */
-       descr->dmac_cmd_status = cmd_status;
+       return descr->dmac_cmd_status & SPIDER_NET_DESCR_IND_PROC_MASK;
 }
 
 /**
@@ -329,26 +302,25 @@ spider_net_free_chain(struct spider_net_card *card,
 static int
 spider_net_init_chain(struct spider_net_card *card,
                       struct spider_net_descr_chain *chain,
-                      struct spider_net_descr *start_descr, int no)
+                      struct spider_net_descr *start_descr,
+                      int no)
 {
        int i;
        struct spider_net_descr *descr;
        dma_addr_t buf;
 
-       atomic_set(&card->rx_chain_refill,0);
-
        descr = start_descr;
        memset(descr, 0, sizeof(*descr) * no);
 
        /* set up the hardware pointers in each descriptor */
        for (i=0; i<no; i++, descr++) {
-               spider_net_set_descr_status(descr, SPIDER_NET_DESCR_NOT_IN_USE);
+               descr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
 
                buf = pci_map_single(card->pdev, descr,
                                     SPIDER_NET_DESCR_SIZE,
                                     PCI_DMA_BIDIRECTIONAL);
 
-               if (buf == DMA_ERROR_CODE)
+               if (pci_dma_mapping_error(buf))
                        goto iommu_error;
 
                descr->bus_addr = buf;
@@ -360,11 +332,7 @@ spider_net_init_chain(struct spider_net_card *card,
        (descr-1)->next = start_descr;
        start_descr->prev = descr-1;
 
-       descr = start_descr;
-       for (i=0; i < no; i++, descr++) {
-               descr->next_descr_addr = descr->next->bus_addr;
-       }
-
+       spin_lock_init(&chain->lock);
        chain->head = start_descr;
        chain->tail = start_descr;
 
@@ -392,7 +360,7 @@ spider_net_free_rx_chain_contents(struct spider_net_card *card)
        struct spider_net_descr *descr;
 
        descr = card->rx_chain.head;
-       while (descr->next != card->rx_chain.head) {
+       do {
                if (descr->skb) {
                        dev_kfree_skb(descr->skb);
                        pci_unmap_single(card->pdev, descr->buf_addr,
@@ -400,7 +368,7 @@ spider_net_free_rx_chain_contents(struct spider_net_card *card)
                                         PCI_DMA_BIDIRECTIONAL);
                }
                descr = descr->next;
-       }
+       } while (descr != card->rx_chain.head);
 }
 
 /**
@@ -433,6 +401,7 @@ spider_net_prepare_rx_descr(struct spider_net_card *card,
        if (!descr->skb) {
                if (netif_msg_rx_err(card) && net_ratelimit())
                        pr_err("Not enough memory to allocate rx buffer\n");
+               card->spider_stats.alloc_rx_skb_error++;
                return -ENOMEM;
        }
        descr->buf_size = bufsize;
@@ -447,15 +416,17 @@ spider_net_prepare_rx_descr(struct spider_net_card *card,
                skb_reserve(descr->skb, SPIDER_NET_RXBUF_ALIGN - offset);
        /* io-mmu-map the skb */
        buf = pci_map_single(card->pdev, descr->skb->data,
-                            SPIDER_NET_MAX_FRAME, PCI_DMA_BIDIRECTIONAL);
+                       SPIDER_NET_MAX_FRAME, PCI_DMA_FROMDEVICE);
        descr->buf_addr = buf;
-       if (buf == DMA_ERROR_CODE) {
+       if (pci_dma_mapping_error(buf)) {
                dev_kfree_skb_any(descr->skb);
                if (netif_msg_rx_err(card) && net_ratelimit())
                        pr_err("Could not iommu-map rx buffer\n");
-               spider_net_set_descr_status(descr, SPIDER_NET_DESCR_NOT_IN_USE);
+               card->spider_stats.rx_iommu_map_error++;
+               descr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
        } else {
-               descr->dmac_cmd_status = SPIDER_NET_DMAC_RX_CARDOWNED;
+               descr->dmac_cmd_status = SPIDER_NET_DESCR_CARDOWNED |
+                                        SPIDER_NET_DMAC_NOINTR_COMPLETE;
        }
 
        return error;
@@ -469,7 +440,7 @@ spider_net_prepare_rx_descr(struct spider_net_card *card,
  * chip by writing to the appropriate register. DMA is enabled in
  * spider_net_enable_rxdmac.
  */
-static void
+static inline void
 spider_net_enable_rxchtails(struct spider_net_card *card)
 {
        /* assume chain is aligned correctly */
@@ -484,7 +455,7 @@ spider_net_enable_rxchtails(struct spider_net_card *card)
  * spider_net_enable_rxdmac enables the DMA controller by setting RX_DMA_EN
  * in the GDADMACCNTR register
  */
-static void
+static inline void
 spider_net_enable_rxdmac(struct spider_net_card *card)
 {
        wmb();
@@ -501,23 +472,24 @@ spider_net_enable_rxdmac(struct spider_net_card *card)
 static void
 spider_net_refill_rx_chain(struct spider_net_card *card)
 {
-       struct spider_net_descr_chain *chain;
-
-       chain = &card->rx_chain;
+       struct spider_net_descr_chain *chain = &card->rx_chain;
+       unsigned long flags;
 
        /* one context doing the refill (and a second context seeing that
         * and omitting it) is ok. If called by NAPI, we'll be called again
         * as spider_net_decode_one_descr is called several times. If some
         * interrupt calls us, the NAPI is about to clean up anyway. */
-       if (atomic_inc_return(&card->rx_chain_refill) == 1)
-               while (spider_net_get_descr_status(chain->head) ==
-                      SPIDER_NET_DESCR_NOT_IN_USE) {
-                       if (spider_net_prepare_rx_descr(card, chain->head))
-                               break;
-                       chain->head = chain->head->next;
-               }
+       if (!spin_trylock_irqsave(&chain->lock, flags))
+               return;
 
-       atomic_dec(&card->rx_chain_refill);
+       while (spider_net_get_descr_status(chain->head) ==
+                       SPIDER_NET_DESCR_NOT_IN_USE) {
+               if (spider_net_prepare_rx_descr(card, chain->head))
+                       break;
+               chain->head = chain->head->next;
+       }
+
+       spin_unlock_irqrestore(&chain->lock, flags);
 }
 
 /**
@@ -554,111 +526,6 @@ error:
        return result;
 }
 
-/**
- * spider_net_release_tx_descr - processes a used tx descriptor
- * @card: card structure
- * @descr: descriptor to release
- *
- * releases a used tx descriptor (unmapping, freeing of skb)
- */
-static void
-spider_net_release_tx_descr(struct spider_net_card *card,
-                           struct spider_net_descr *descr)
-{
-       struct sk_buff *skb;
-
-       /* unmap the skb */
-       skb = descr->skb;
-       pci_unmap_single(card->pdev, descr->buf_addr, skb->len,
-                        PCI_DMA_BIDIRECTIONAL);
-
-       dev_kfree_skb_any(skb);
-
-       /* set status to not used */
-       spider_net_set_descr_status(descr, SPIDER_NET_DESCR_NOT_IN_USE);
-}
-
-/**
- * spider_net_release_tx_chain - processes sent tx descriptors
- * @card: adapter structure
- * @brutal: if set, don't care about whether descriptor seems to be in use
- *
- * returns 0 if the tx ring is empty, otherwise 1.
- *
- * spider_net_release_tx_chain releases the tx descriptors that spider has
- * finished with (if non-brutal) or simply release tx descriptors (if brutal).
- * If some other context is calling this function, we return 1 so that we're
- * scheduled again (if we were scheduled) and will not loose initiative.
- */
-static int
-spider_net_release_tx_chain(struct spider_net_card *card, int brutal)
-{
-       struct spider_net_descr_chain *tx_chain = &card->tx_chain;
-       enum spider_net_descr_status status;
-
-       if (atomic_inc_return(&card->tx_chain_release) != 1) {
-               atomic_dec(&card->tx_chain_release);
-               return 1;
-       }
-
-       for (;;) {
-               status = spider_net_get_descr_status(tx_chain->tail);
-               switch (status) {
-               case SPIDER_NET_DESCR_CARDOWNED:
-                       if (!brutal)
-                               goto out;
-                       /* fallthrough, if we release the descriptors
-                        * brutally (then we don't care about
-                        * SPIDER_NET_DESCR_CARDOWNED) */
-               case SPIDER_NET_DESCR_RESPONSE_ERROR:
-               case SPIDER_NET_DESCR_PROTECTION_ERROR:
-               case SPIDER_NET_DESCR_FORCE_END:
-                       if (netif_msg_tx_err(card))
-                               pr_err("%s: forcing end of tx descriptor "
-                                      "with status x%02x\n",
-                                      card->netdev->name, status);
-                       card->netdev_stats.tx_dropped++;
-                       break;
-
-               case SPIDER_NET_DESCR_COMPLETE:
-                       card->netdev_stats.tx_packets++;
-                       card->netdev_stats.tx_bytes +=
-                               tx_chain->tail->skb->len;
-                       break;
-
-               default: /* any other value (== SPIDER_NET_DESCR_NOT_IN_USE) */
-                       goto out;
-               }
-               spider_net_release_tx_descr(card, tx_chain->tail);
-               tx_chain->tail = tx_chain->tail->next;
-       }
-out:
-       atomic_dec(&card->tx_chain_release);
-
-       netif_wake_queue(card->netdev);
-
-       if (status == SPIDER_NET_DESCR_CARDOWNED)
-               return 1;
-       return 0;
-}
-
-/**
- * spider_net_cleanup_tx_ring - cleans up the TX ring
- * @card: card structure
- *
- * spider_net_cleanup_tx_ring is called by the tx_timer (as we don't use
- * interrupts to cleanup our TX ring) and returns sent packets to the stack
- * by freeing them
- */
-static void
-spider_net_cleanup_tx_ring(struct spider_net_card *card)
-{
-       if ( (spider_net_release_tx_chain(card, 0)) &&
-             (card->netdev->flags & IFF_UP) ) {
-               mod_timer(&card->tx_timer, jiffies + SPIDER_NET_TX_TIMER);
-       }
-}
-
 /**
  * spider_net_get_multicast_hash - generates hash for multicast filter table
  * @addr: multicast address
@@ -762,130 +629,178 @@ spider_net_disable_rxdmac(struct spider_net_card *card)
 }
 
 /**
- * spider_net_stop - called upon ifconfig down
- * @netdev: interface device structure
+ * spider_net_prepare_tx_descr - fill tx descriptor with skb data
+ * @card: card structure
+ * @descr: descriptor structure to fill out
+ * @skb: packet to use
  *
- * always returns 0
+ * returns 0 on success, <0 on failure.
+ *
+ * fills out the descriptor structure with skb data and len. Copies data,
+ * if needed (32bit DMA!)
  */
-int
-spider_net_stop(struct net_device *netdev)
+static int
+spider_net_prepare_tx_descr(struct spider_net_card *card,
+                           struct sk_buff *skb)
 {
-       struct spider_net_card *card = netdev_priv(netdev);
-
-       tasklet_kill(&card->rxram_full_tl);
-       netif_poll_disable(netdev);
-       netif_carrier_off(netdev);
-       netif_stop_queue(netdev);
-       del_timer_sync(&card->tx_timer);
+       struct spider_net_descr *descr;
+       dma_addr_t buf;
+       unsigned long flags;
 
-       /* disable/mask all interrupts */
-       spider_net_write_reg(card, SPIDER_NET_GHIINT0MSK, 0);
-       spider_net_write_reg(card, SPIDER_NET_GHIINT1MSK, 0);
-       spider_net_write_reg(card, SPIDER_NET_GHIINT2MSK, 0);
+       buf = pci_map_single(card->pdev, skb->data, skb->len, PCI_DMA_TODEVICE);
+       if (pci_dma_mapping_error(buf)) {
+               if (netif_msg_tx_err(card) && net_ratelimit())
+                       pr_err("could not iommu-map packet (%p, %i). "
+                                 "Dropping packet\n", skb->data, skb->len);
+               card->spider_stats.tx_iommu_map_error++;
+               return -ENOMEM;
+       }
 
-       /* free_irq(netdev->irq, netdev);*/
-       free_irq(to_pci_dev(netdev->class_dev.dev)->irq, netdev);
+       spin_lock_irqsave(&card->tx_chain.lock, flags);
+       descr = card->tx_chain.head;
+       card->tx_chain.head = descr->next;
 
-       spider_net_write_reg(card, SPIDER_NET_GDTDMACCNTR,
-                            SPIDER_NET_DMA_TX_FEND_VALUE);
+       descr->buf_addr = buf;
+       descr->buf_size = skb->len;
+       descr->next_descr_addr = 0;
+       descr->skb = skb;
+       descr->data_status = 0;
 
-       /* turn off DMA, force end */
-       spider_net_disable_rxdmac(card);
+       descr->dmac_cmd_status =
+                       SPIDER_NET_DESCR_CARDOWNED | SPIDER_NET_DMAC_NOCS;
+       spin_unlock_irqrestore(&card->tx_chain.lock, flags);
 
-       /* release chains */
-       spider_net_release_tx_chain(card, 1);
+       if (skb->protocol == htons(ETH_P_IP))
+               switch (skb->nh.iph->protocol) {
+               case IPPROTO_TCP:
+                       descr->dmac_cmd_status |= SPIDER_NET_DMAC_TCP;
+                       break;
+               case IPPROTO_UDP:
+                       descr->dmac_cmd_status |= SPIDER_NET_DMAC_UDP;
+                       break;
+               }
 
-       spider_net_free_chain(card, &card->tx_chain);
-       spider_net_free_chain(card, &card->rx_chain);
+       /* Chain the bus address, so that the DMA engine finds this descr. */
+       descr->prev->next_descr_addr = descr->bus_addr;
 
+       card->netdev->trans_start = jiffies; /* set netdev watchdog timer */
        return 0;
 }
 
-/**
- * spider_net_get_next_tx_descr - returns the next available tx descriptor
- * @card: device structure to get descriptor from
- *
- * returns the address of the next descriptor, or NULL if not available.
- */
-static struct spider_net_descr *
-spider_net_get_next_tx_descr(struct spider_net_card *card)
+static int
+spider_net_set_low_watermark(struct spider_net_card *card)
 {
-       /* check, if head points to not-in-use descr */
-       if ( spider_net_get_descr_status(card->tx_chain.head) ==
-            SPIDER_NET_DESCR_NOT_IN_USE ) {
-               return card->tx_chain.head;
-       } else {
-               return NULL;
+       unsigned long flags;
+       int status;
+       int cnt=0;
+       int i;
+       struct spider_net_descr *descr = card->tx_chain.tail;
+
+       /* Measure the length of the queue. Measurement does not
+        * need to be precise -- does not need a lock. */
+       while (descr != card->tx_chain.head) {
+               status = descr->dmac_cmd_status & SPIDER_NET_DESCR_NOT_IN_USE;
+               if (status == SPIDER_NET_DESCR_NOT_IN_USE)
+                       break;
+               descr = descr->next;
+               cnt++;
        }
-}
 
-/**
- * spider_net_set_txdescr_cmdstat - sets the tx descriptor command field
- * @descr: descriptor structure to fill out
- * @skb: packet to consider
- *
- * fills out the command and status field of the descriptor structure,
- * depending on hardware checksum settings.
- */
-static void
-spider_net_set_txdescr_cmdstat(struct spider_net_descr *descr,
-                              struct sk_buff *skb)
-{
-       /* make sure the other fields in the descriptor are written */
-       wmb();
+       /* If TX queue is short, don't even bother with interrupts */
+       if (cnt < card->num_tx_desc/4)
+               return cnt;
 
-       if (skb->ip_summed != CHECKSUM_HW) {
-               descr->dmac_cmd_status = SPIDER_NET_DMAC_CMDSTAT_NOCS;
-               return;
-       }
+       /* Set low-watermark 3/4th's of the way into the queue. */
+       descr = card->tx_chain.tail;
+       cnt = (cnt*3)/4;
+       for (i=0;i<cnt; i++)
+               descr = descr->next;
 
-       /* is packet ip?
-        * if yes: tcp? udp? */
-       if (skb->protocol == htons(ETH_P_IP)) {
-               if (skb->nh.iph->protocol == IPPROTO_TCP)
-                       descr->dmac_cmd_status = SPIDER_NET_DMAC_CMDSTAT_TCPCS;
-               else if (skb->nh.iph->protocol == IPPROTO_UDP)
-                       descr->dmac_cmd_status = SPIDER_NET_DMAC_CMDSTAT_UDPCS;
-               else /* the stack should checksum non-tcp and non-udp
-                       packets on his own: NETIF_F_IP_CSUM */
-                       descr->dmac_cmd_status = SPIDER_NET_DMAC_CMDSTAT_NOCS;
-       }
+       /* Set the new watermark, clear the old watermark */
+       spin_lock_irqsave(&card->tx_chain.lock, flags);
+       descr->dmac_cmd_status |= SPIDER_NET_DESCR_TXDESFLG;
+       if (card->low_watermark && card->low_watermark != descr)
+               card->low_watermark->dmac_cmd_status =
+                    card->low_watermark->dmac_cmd_status & ~SPIDER_NET_DESCR_TXDESFLG;
+       card->low_watermark = descr;
+       spin_unlock_irqrestore(&card->tx_chain.lock, flags);
+       return cnt;
 }
 
 /**
- * spider_net_prepare_tx_descr - fill tx descriptor with skb data
- * @card: card structure
- * @descr: descriptor structure to fill out
- * @skb: packet to use
+ * spider_net_release_tx_chain - processes sent tx descriptors
+ * @card: adapter structure
+ * @brutal: if set, don't care about whether descriptor seems to be in use
  *
- * returns 0 on success, <0 on failure.
+ * returns 0 if the tx ring is empty, otherwise 1.
  *
- * fills out the descriptor structure with skb data and len. Copies data,
- * if needed (32bit DMA!)
+ * spider_net_release_tx_chain releases the tx descriptors that spider has
+ * finished with (if non-brutal) or simply release tx descriptors (if brutal).
+ * If some other context is calling this function, we return 1 so that we're
+ * scheduled again (if we were scheduled) and will not loose initiative.
  */
 static int
-spider_net_prepare_tx_descr(struct spider_net_card *card,
-                           struct spider_net_descr *descr,
-                           struct sk_buff *skb)
+spider_net_release_tx_chain(struct spider_net_card *card, int brutal)
 {
-       dma_addr_t buf;
+       struct spider_net_descr_chain *chain = &card->tx_chain;
+       struct spider_net_descr *descr;
+       struct sk_buff *skb;
+       u32 buf_addr;
+       unsigned long flags;
+       int status;
 
-       buf = pci_map_single(card->pdev, skb->data,
-                            skb->len, PCI_DMA_BIDIRECTIONAL);
-       if (buf == DMA_ERROR_CODE) {
-               if (netif_msg_tx_err(card) && net_ratelimit())
-                       pr_err("could not iommu-map packet (%p, %i). "
-                                 "Dropping packet\n", skb->data, skb->len);
-               return -ENOMEM;
-       }
+       while (chain->tail != chain->head) {
+               spin_lock_irqsave(&chain->lock, flags);
+               descr = chain->tail;
 
-       descr->buf_addr = buf;
-       descr->buf_size = skb->len;
-       descr->skb = skb;
-       descr->data_status = 0;
+               status = spider_net_get_descr_status(descr);
+               switch (status) {
+               case SPIDER_NET_DESCR_COMPLETE:
+                       card->netdev_stats.tx_packets++;
+                       card->netdev_stats.tx_bytes += descr->skb->len;
+                       break;
+
+               case SPIDER_NET_DESCR_CARDOWNED:
+                       if (!brutal) {
+                               spin_unlock_irqrestore(&chain->lock, flags);
+                               return 1;
+                       }
 
-       spider_net_set_txdescr_cmdstat(descr,skb);
+                       /* fallthrough, if we release the descriptors
+                        * brutally (then we don't care about
+                        * SPIDER_NET_DESCR_CARDOWNED) */
 
+               case SPIDER_NET_DESCR_RESPONSE_ERROR:
+               case SPIDER_NET_DESCR_PROTECTION_ERROR:
+               case SPIDER_NET_DESCR_FORCE_END:
+                       if (netif_msg_tx_err(card))
+                               pr_err("%s: forcing end of tx descriptor "
+                                      "with status x%02x\n",
+                                      card->netdev->name, status);
+                       card->netdev_stats.tx_errors++;
+                       break;
+
+               default:
+                       card->netdev_stats.tx_dropped++;
+                       if (!brutal) {
+                               spin_unlock_irqrestore(&chain->lock, flags);
+                               return 1;
+                       }
+               }
+
+               chain->tail = descr->next;
+               descr->dmac_cmd_status |= SPIDER_NET_DESCR_NOT_IN_USE;
+               skb = descr->skb;
+               buf_addr = descr->buf_addr;
+               spin_unlock_irqrestore(&chain->lock, flags);
+
+               /* unmap the skb */
+               if (skb) {
+                       pci_unmap_single(card->pdev, buf_addr, skb->len,
+                                       PCI_DMA_TODEVICE);
+                       dev_kfree_skb(skb);
+               }
+       }
        return 0;
 }
 
@@ -894,21 +809,39 @@ spider_net_prepare_tx_descr(struct spider_net_card *card,
  * @card: card structure
  * @descr: descriptor address to enable TX processing at
  *
- * spider_net_kick_tx_dma writes the current tx chain head as start address
- * of the tx descriptor chain and enables the transmission DMA engine
+ * This routine will start the transmit DMA running if
+ * it is not already running. This routine ned only be
+ * called when queueing a new packet to an empty tx queue.
+ * Writes the current tx chain head as start address
+ * of the tx descriptor chain and enables the transmission
+ * DMA engine.
  */
-static void
-spider_net_kick_tx_dma(struct spider_net_card *card,
-                      struct spider_net_descr *descr)
+static inline void
+spider_net_kick_tx_dma(struct spider_net_card *card)
 {
-       /* this is the only descriptor in the output chain.
-        * Enable TX DMA */
+       struct spider_net_descr *descr;
 
-       spider_net_write_reg(card, SPIDER_NET_GDTDCHA,
-                            descr->bus_addr);
+       if (spider_net_read_reg(card, SPIDER_NET_GDTDMACCNTR) &
+                       SPIDER_NET_TX_DMA_EN)
+               goto out;
 
-       spider_net_write_reg(card, SPIDER_NET_GDTDMACCNTR,
-                            SPIDER_NET_DMA_TX_VALUE);
+       descr = card->tx_chain.tail;
+       for (;;) {
+               if (spider_net_get_descr_status(descr) ==
+                               SPIDER_NET_DESCR_CARDOWNED) {
+                       spider_net_write_reg(card, SPIDER_NET_GDTDCHA,
+                                       descr->bus_addr);
+                       spider_net_write_reg(card, SPIDER_NET_GDTDMACCNTR,
+                                       SPIDER_NET_DMA_TX_VALUE);
+                       break;
+               }
+               if (descr == card->tx_chain.head)
+                       break;
+               descr = descr->next;
+       }
+
+out:
+       mod_timer(&card->tx_timer, jiffies + SPIDER_NET_TX_TIMER);
 }
 
 /**
@@ -916,47 +849,48 @@ spider_net_kick_tx_dma(struct spider_net_card *card,
  * @skb: packet to send out
  * @netdev: interface device structure
  *
- * returns 0 on success, <0 on failure
+ * returns 0 on success, !0 on failure
  */
 static int
 spider_net_xmit(struct sk_buff *skb, struct net_device *netdev)
 {
+       int cnt;
        struct spider_net_card *card = netdev_priv(netdev);
-       struct spider_net_descr *descr;
-       int result;
+       struct spider_net_descr_chain *chain = &card->tx_chain;
 
        spider_net_release_tx_chain(card, 0);
 
-       descr = spider_net_get_next_tx_descr(card);
-
-       if (!descr)
-               goto error;
+       if ((chain->head->next == chain->tail->prev) ||
+          (spider_net_prepare_tx_descr(card, skb) != 0)) {
 
-       result = spider_net_prepare_tx_descr(card, descr, skb);
-       if (result)
-               goto error;
-
-       card->tx_chain.head = card->tx_chain.head->next;
-
-       if (spider_net_get_descr_status(descr->prev) !=
-           SPIDER_NET_DESCR_CARDOWNED) {
-               /* make sure the current descriptor is in memory. Then
-                * kicking it on again makes sense, if the previous is not
-                * card-owned anymore. Check the previous descriptor twice
-                * to omit an mb() in heavy traffic cases */
-               mb();
-               if (spider_net_get_descr_status(descr->prev) !=
-                   SPIDER_NET_DESCR_CARDOWNED)
-                       spider_net_kick_tx_dma(card, descr);
+               card->netdev_stats.tx_dropped++;
+               netif_stop_queue(netdev);
+               return NETDEV_TX_BUSY;
        }
 
-       mod_timer(&card->tx_timer, jiffies + SPIDER_NET_TX_TIMER);
-
+       cnt = spider_net_set_low_watermark(card);
+       if (cnt < 5)
+               spider_net_kick_tx_dma(card);
        return NETDEV_TX_OK;
+}
 
-error:
-       card->netdev_stats.tx_dropped++;
-       return NETDEV_TX_BUSY;
+/**
+ * spider_net_cleanup_tx_ring - cleans up the TX ring
+ * @card: card structure
+ *
+ * spider_net_cleanup_tx_ring is called by either the tx_timer
+ * or from the NAPI polling routine.
+ * This routine releases resources associted with transmitted
+ * packets, including updating the queue tail pointer.
+ */
+static void
+spider_net_cleanup_tx_ring(struct spider_net_card *card)
+{
+       if ((spider_net_release_tx_chain(card, 0) != 0) &&
+           (card->netdev->flags & IFF_UP)) {
+               spider_net_kick_tx_dma(card);
+               netif_wake_queue(card->netdev);
+       }
 }
 
 /**
@@ -1003,7 +937,7 @@ spider_net_pass_skb_up(struct spider_net_descr *descr,
 
        /* unmap descriptor */
        pci_unmap_single(card->pdev, descr->buf_addr, SPIDER_NET_MAX_FRAME,
-                        PCI_DMA_BIDIRECTIONAL);
+                       PCI_DMA_FROMDEVICE);
 
        /* the cases we'll throw away the packet immediately */
        if (data_error & SPIDER_NET_DESTROY_RX_FLAGS) {
@@ -1011,6 +945,7 @@ spider_net_pass_skb_up(struct spider_net_descr *descr,
                        pr_err("error in received descriptor found, "
                               "data_status=x%08x, data_error=x%08x\n",
                               data_status, data_error);
+               card->spider_stats.rx_desc_error++;
                return 0;
        }
 
@@ -1068,14 +1003,11 @@ spider_net_pass_skb_up(struct spider_net_descr *descr,
 static int
 spider_net_decode_one_descr(struct spider_net_card *card, int napi)
 {
-       enum spider_net_descr_status status;
-       struct spider_net_descr *descr;
-       struct spider_net_descr_chain *chain;
+       struct spider_net_descr_chain *chain = &card->rx_chain;
+       struct spider_net_descr *descr = chain->tail;
+       int status;
        int result;
 
-       chain = &card->rx_chain;
-       descr = chain->tail;
-
        status = spider_net_get_descr_status(descr);
 
        if (status == SPIDER_NET_DESCR_CARDOWNED) {
@@ -1104,23 +1036,25 @@ spider_net_decode_one_descr(struct spider_net_card *card, int napi)
                               card->netdev->name, status);
                card->netdev_stats.rx_dropped++;
                pci_unmap_single(card->pdev, descr->buf_addr,
-                                SPIDER_NET_MAX_FRAME, PCI_DMA_BIDIRECTIONAL);
+                               SPIDER_NET_MAX_FRAME, PCI_DMA_FROMDEVICE);
                dev_kfree_skb_irq(descr->skb);
                goto refill;
        }
 
        if ( (status != SPIDER_NET_DESCR_COMPLETE) &&
             (status != SPIDER_NET_DESCR_FRAME_END) ) {
-               if (netif_msg_rx_err(card))
+               if (netif_msg_rx_err(card)) {
                        pr_err("%s: RX descriptor with state %d\n",
                               card->netdev->name, status);
+                       card->spider_stats.rx_desc_unk_state++;
+               }
                goto refill;
        }
 
        /* ok, we've got a packet in descr */
        result = spider_net_pass_skb_up(descr, card, napi);
 refill:
-       spider_net_set_descr_status(descr, SPIDER_NET_DESCR_NOT_IN_USE);
+       descr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
        /* change the descriptor state: */
        if (!napi)
                spider_net_refill_rx_chain(card);
@@ -1147,6 +1081,7 @@ spider_net_poll(struct net_device *netdev, int *budget)
        int packets_to_do, packets_done = 0;
        int no_more_packets = 0;
 
+       spider_net_cleanup_tx_ring(card);
        packets_to_do = min(*budget, netdev->quota);
 
        while (packets_to_do) {
@@ -1291,21 +1226,6 @@ spider_net_set_mac(struct net_device *netdev, void *p)
        return 0;
 }
 
-/**
- * spider_net_enable_txdmac - enables a TX DMA controller
- * @card: card structure
- *
- * spider_net_enable_txdmac enables the TX DMA controller by setting the
- * descriptor chain tail address
- */
-static void
-spider_net_enable_txdmac(struct spider_net_card *card)
-{
-       /* assume chain is aligned correctly */
-       spider_net_write_reg(card, SPIDER_NET_GDTDCHA,
-                            card->tx_chain.tail->bus_addr);
-}
-
 /**
  * spider_net_handle_rxram_full - cleans up RX ring upon RX RAM full interrupt
  * @card: card structure
@@ -1352,12 +1272,15 @@ spider_net_handle_error_irq(struct spider_net_card *card, u32 status_reg)
        case SPIDER_NET_PHYINT:
        case SPIDER_NET_GMAC2INT:
        case SPIDER_NET_GMAC1INT:
-       case SPIDER_NET_GIPSINT:
        case SPIDER_NET_GFIFOINT:
        case SPIDER_NET_DMACINT:
        case SPIDER_NET_GSYSINT:
                break; */
 
+       case SPIDER_NET_GIPSINT:
+               show_error = 0;
+               break;
+
        case SPIDER_NET_GPWOPCMPINT:
                /* PHY write operation completed */
                show_error = 0;
@@ -1416,9 +1339,10 @@ spider_net_handle_error_irq(struct spider_net_card *card, u32 status_reg)
        case SPIDER_NET_GDTDCEINT:
                /* chain end. If a descriptor should be sent, kick off
                 * tx dma
-               if (card->tx_chain.tail == card->tx_chain.head)
+               if (card->tx_chain.tail != card->tx_chain.head)
                        spider_net_kick_tx_dma(card);
-               show_error = 0; */
+               */
+               show_error = 0;
                break;
 
        /* case SPIDER_NET_G1TMCNTINT: not used. print a message */
@@ -1442,7 +1366,7 @@ spider_net_handle_error_irq(struct spider_net_card *card, u32 status_reg)
        case SPIDER_NET_GRFAFLLINT: /* fallthrough */
        case SPIDER_NET_GRMFLLINT:
                if (netif_msg_intr(card) && net_ratelimit())
-                       pr_err("Spider RX RAM full, incoming packets "
+                       pr_debug("Spider RX RAM full, incoming packets "
                               "might be discarded!\n");
                spider_net_rx_irq_off(card);
                tasklet_schedule(&card->rxram_full_tl);
@@ -1463,7 +1387,7 @@ spider_net_handle_error_irq(struct spider_net_card *card, u32 status_reg)
                if (netif_msg_intr(card))
                        pr_err("got descriptor chain end interrupt, "
                               "restarting DMAC %c.\n",
-                              'D'+i-SPIDER_NET_GDDDCEINT);
+                              'D'-(i-SPIDER_NET_GDDDCEINT)/3);
                spider_net_refill_rx_chain(card);
                spider_net_enable_rxdmac(card);
                show_error = 0;
@@ -1532,8 +1456,9 @@ spider_net_handle_error_irq(struct spider_net_card *card, u32 status_reg)
        }
 
        if ((show_error) && (netif_msg_intr(card)))
-               pr_err("Got error interrupt, GHIINT0STS = 0x%08x, "
+               pr_err("Got error interrupt on %s, GHIINT0STS = 0x%08x, "
                       "GHIINT1STS = 0x%08x, GHIINT2STS = 0x%08x\n",
+                      card->netdev->name,
                       status_reg, error_reg1, error_reg2);
 
        /* clear interrupt sources */
@@ -1554,7 +1479,7 @@ spider_net_handle_error_irq(struct spider_net_card *card, u32 status_reg)
  * interrupts for this device and makes the stack poll the driver
  */
 static irqreturn_t
-spider_net_interrupt(int irq, void *ptr, struct pt_regs *regs)
+spider_net_interrupt(int irq, void *ptr)
 {
        struct net_device *netdev = ptr;
        struct spider_net_card *card = netdev_priv(netdev);
@@ -1569,6 +1494,8 @@ spider_net_interrupt(int irq, void *ptr, struct pt_regs *regs)
                spider_net_rx_irq_off(card);
                netif_rx_schedule(netdev);
        }
+       if (status_reg & SPIDER_NET_TXINT)
+               netif_rx_schedule(netdev);
 
        if (status_reg & SPIDER_NET_ERRINT )
                spider_net_handle_error_irq(card, status_reg);
@@ -1590,7 +1517,7 @@ static void
 spider_net_poll_controller(struct net_device *netdev)
 {
        disable_irq(netdev->irq);
-       spider_net_interrupt(netdev->irq, netdev, NULL);
+       spider_net_interrupt(netdev->irq, netdev);
        enable_irq(netdev->irq);
 }
 #endif /* CONFIG_NET_POLL_CONTROLLER */
@@ -1652,7 +1579,8 @@ spider_net_enable_card(struct spider_net_card *card)
                { SPIDER_NET_GFTRESTRT, SPIDER_NET_RESTART_VALUE },
 
                { SPIDER_NET_GMRWOLCTRL, 0 },
-               { SPIDER_NET_GTESTMD, 0 },
+               { SPIDER_NET_GTESTMD, 0x10000000 },
+               { SPIDER_NET_GTTQMSK, 0x00400040 },
 
                { SPIDER_NET_GMACINTEN, 0 },
 
@@ -1691,9 +1619,6 @@ spider_net_enable_card(struct spider_net_card *card)
 
        spider_net_write_reg(card, SPIDER_NET_GRXDMAEN, SPIDER_NET_WOL_VALUE);
 
-       /* set chain tail adress for TX chain */
-       spider_net_enable_txdmac(card);
-
        spider_net_write_reg(card, SPIDER_NET_GMACLENLMT,
                             SPIDER_NET_LENLMT_VALUE);
        spider_net_write_reg(card, SPIDER_NET_GMACMODE,
@@ -1708,6 +1633,9 @@ spider_net_enable_card(struct spider_net_card *card)
                             SPIDER_NET_INT1_MASK_VALUE);
        spider_net_write_reg(card, SPIDER_NET_GHIINT2MSK,
                             SPIDER_NET_INT2_MASK_VALUE);
+
+       spider_net_write_reg(card, SPIDER_NET_GDTDMACCNTR,
+                            SPIDER_NET_GDTBSTA);
 }
 
 /**
@@ -1723,16 +1651,26 @@ int
 spider_net_open(struct net_device *netdev)
 {
        struct spider_net_card *card = netdev_priv(netdev);
-       int result;
+       struct spider_net_descr *descr;
+       int i, result;
 
        result = -ENOMEM;
-       if (spider_net_init_chain(card, &card->tx_chain,
-                         card->descr, tx_descriptors))
+       if (spider_net_init_chain(card, &card->tx_chain, card->descr,
+                                 card->num_tx_desc))
                goto alloc_tx_failed;
+
+       card->low_watermark = NULL;
+
+       /* rx_chain is after tx_chain, so offset is descr + tx_count */
        if (spider_net_init_chain(card, &card->rx_chain,
-                         card->descr + tx_descriptors, rx_descriptors))
+                                 card->descr + card->num_tx_desc,
+                                 card->num_rx_desc))
                goto alloc_rx_failed;
 
+       descr = card->rx_chain.head;
+       for (i=0; i < card->num_rx_desc; i++, descr++)
+               descr->next_descr_addr = descr->next->bus_addr;
+
        /* allocate rx skbs */
        if (spider_net_alloc_rx_skbs(card))
                goto alloc_skbs_failed;
@@ -1743,7 +1681,7 @@ spider_net_open(struct net_device *netdev)
 
        result = -EBUSY;
        if (request_irq(netdev->irq, spider_net_interrupt,
-                            SA_SHIRQ, netdev->name, netdev))
+                            IRQF_SHARED, netdev->name, netdev))
                goto register_int_failed;
 
        spider_net_enable_card(card);
@@ -1792,15 +1730,7 @@ spider_net_setup_phy(struct spider_net_card *card)
        if (phy->def->ops->setup_forced)
                phy->def->ops->setup_forced(phy, SPEED_1000, DUPLEX_FULL);
 
-       /* the following two writes could be moved to sungem_phy.c */
-       /* enable fiber mode */
-       spider_net_write_phy(card->netdev, 1, MII_NCONFIG, 0x9020);
-       /* LEDs active in both modes, autosense prio = fiber */
-       spider_net_write_phy(card->netdev, 1, MII_NCONFIG, 0x945f);
-
-       /* switch off fibre autoneg */
-       spider_net_write_phy(card->netdev, 1, MII_NCONFIG, 0xfc01);
-       spider_net_write_phy(card->netdev, 1, 0x0b, 0x0004);
+       phy->def->ops->enable_fiber(phy);
 
        phy->def->ops->read_link(phy);
        pr_info("Found %s with %i Mbps, %s-duplex.\n", phy->def->name,
@@ -1819,10 +1749,10 @@ spider_net_setup_phy(struct spider_net_card *card)
  */
 static int
 spider_net_download_firmware(struct spider_net_card *card,
-                            u8 *firmware_ptr)
+                            const void *firmware_ptr)
 {
        int sequencer, i;
-       u32 *fw_ptr = (u32 *)firmware_ptr;
+       const u32 *fw_ptr = firmware_ptr;
 
        /* stop sequencers */
        spider_net_write_reg(card, SPIDER_NET_GSINIT,
@@ -1879,7 +1809,7 @@ spider_net_init_firmware(struct spider_net_card *card)
 {
        struct firmware *firmware = NULL;
        struct device_node *dn;
-       u8 *fw_prop = NULL;
+       const u8 *fw_prop = NULL;
        int err = -ENOENT;
        int fw_size;
 
@@ -1905,7 +1835,7 @@ try_host_fw:
        if (!dn)
                goto out_err;
 
-       fw_prop = (u8 *)get_property(dn, "firmware", &fw_size);
+       fw_prop = get_property(dn, "firmware", &fw_size);
        if (!fw_prop)
                goto out_err;
 
@@ -1945,7 +1875,7 @@ spider_net_workaround_rxramfull(struct spider_net_card *card)
        /* empty sequencer data */
        for (sequencer = 0; sequencer < SPIDER_NET_FIRMWARE_SEQS;
             sequencer++) {
-               spider_net_write_reg(card, SPIDER_NET_GSnPRGDAT +
+               spider_net_write_reg(card, SPIDER_NET_GSnPRGADR +
                                     sequencer * 8, 0x0);
                for (i = 0; i < SPIDER_NET_FIRMWARE_SEQWORDS; i++) {
                        spider_net_write_reg(card, SPIDER_NET_GSnPRGDAT +
@@ -1961,6 +1891,48 @@ spider_net_workaround_rxramfull(struct spider_net_card *card)
                             SPIDER_NET_CKRCTRL_STOP_VALUE);
 }
 
+/**
+ * spider_net_stop - called upon ifconfig down
+ * @netdev: interface device structure
+ *
+ * always returns 0
+ */
+int
+spider_net_stop(struct net_device *netdev)
+{
+       struct spider_net_card *card = netdev_priv(netdev);
+
+       tasklet_kill(&card->rxram_full_tl);
+       netif_poll_disable(netdev);
+       netif_carrier_off(netdev);
+       netif_stop_queue(netdev);
+       del_timer_sync(&card->tx_timer);
+
+       /* disable/mask all interrupts */
+       spider_net_write_reg(card, SPIDER_NET_GHIINT0MSK, 0);
+       spider_net_write_reg(card, SPIDER_NET_GHIINT1MSK, 0);
+       spider_net_write_reg(card, SPIDER_NET_GHIINT2MSK, 0);
+
+       /* free_irq(netdev->irq, netdev);*/
+       free_irq(to_pci_dev(netdev->class_dev.dev)->irq, netdev);
+
+       spider_net_write_reg(card, SPIDER_NET_GDTDMACCNTR,
+                            SPIDER_NET_DMA_TX_FEND_VALUE);
+
+       /* turn off DMA, force end */
+       spider_net_disable_rxdmac(card);
+
+       /* release chains */
+       spider_net_release_tx_chain(card, 1);
+
+       spider_net_free_rx_chain_contents(card);
+
+       spider_net_free_chain(card, &card->tx_chain);
+       spider_net_free_chain(card, &card->rx_chain);
+
+       return 0;
+}
+
 /**
  * spider_net_tx_timeout_task - task scheduled by the watchdog timeout
  * function (to be called not under interrupt status)
@@ -1969,10 +1941,11 @@ spider_net_workaround_rxramfull(struct spider_net_card *card)
  * called as task when tx hangs, resets interface (if interface is up)
  */
 static void
-spider_net_tx_timeout_task(void *data)
+spider_net_tx_timeout_task(struct work_struct *work)
 {
-       struct net_device *netdev = data;
-       struct spider_net_card *card = netdev_priv(netdev);
+       struct spider_net_card *card =
+               container_of(work, struct spider_net_card, tx_timeout_task);
+       struct net_device *netdev = card->netdev;
 
        if (!(netdev->flags & IFF_UP))
                goto out;
@@ -1989,7 +1962,7 @@ spider_net_tx_timeout_task(void *data)
                goto out;
 
        spider_net_open(netdev);
-       spider_net_kick_tx_dma(card, card->tx_chain.head);
+       spider_net_kick_tx_dma(card);
        netif_device_attach(netdev);
 
 out:
@@ -2013,6 +1986,7 @@ spider_net_tx_timeout(struct net_device *netdev)
                schedule_work(&card->tx_timeout_task);
        else
                atomic_dec(&card->tx_timeout_task_counter);
+       card->spider_stats.tx_timeouts++;
 }
 
 /**
@@ -2065,14 +2039,13 @@ spider_net_setup_netdev(struct spider_net_card *card)
        struct net_device *netdev = card->netdev;
        struct device_node *dn;
        struct sockaddr addr;
-       u8 *mac;
+       const u8 *mac;
 
        SET_MODULE_OWNER(netdev);
        SET_NETDEV_DEV(netdev, &card->pdev->dev);
 
        pci_set_drvdata(card->pdev, netdev);
 
-       atomic_set(&card->tx_chain_release,0);
        card->rxram_full_tl.data = (unsigned long) card;
        card->rxram_full_tl.func =
                (void (*)(unsigned long)) spider_net_handle_rxram_full;
@@ -2084,9 +2057,12 @@ spider_net_setup_netdev(struct spider_net_card *card)
 
        card->options.rx_csum = SPIDER_NET_RX_CSUM_DEFAULT;
 
+       card->num_tx_desc = tx_descriptors;
+       card->num_rx_desc = rx_descriptors;
+
        spider_net_setup_netdev_ops(netdev);
 
-       netdev->features = 0;
+       netdev->features = NETIF_F_HW_CSUM | NETIF_F_LLTX;
        /* some time: NETIF_F_HW_VLAN_TX | NETIF_F_HW_VLAN_RX |
         *              NETIF_F_HW_VLAN_FILTER */
 
@@ -2096,7 +2072,7 @@ spider_net_setup_netdev(struct spider_net_card *card)
        if (!dn)
                return -EIO;
 
-       mac = (u8 *)get_property(dn, "local-mac-address", NULL);
+       mac = get_property(dn, "local-mac-address", NULL);
        if (!mac)
                return -EIO;
        memcpy(addr.sa_data, mac, ETH_ALEN);
@@ -2143,7 +2119,7 @@ spider_net_alloc_card(void)
        card = netdev_priv(netdev);
        card->netdev = netdev;
        card->msg_enable = SPIDER_NET_DEFAULT_MSG;
-       INIT_WORK(&card->tx_timeout_task, spider_net_tx_timeout_task, netdev);
+       INIT_WORK(&card->tx_timeout_task, spider_net_tx_timeout_task);
        init_waitqueue_head(&card->waitq);
        atomic_set(&card->tx_timeout_task_counter, 0);
 
@@ -2321,6 +2297,8 @@ static struct pci_driver spider_net_driver = {
  */
 static int __init spider_net_init(void)
 {
+       printk(KERN_INFO "Spidernet version %s.\n", VERSION);
+
        if (rx_descriptors < SPIDER_NET_RX_DESCRIPTORS_MIN) {
                rx_descriptors = SPIDER_NET_RX_DESCRIPTORS_MIN;
                pr_info("adjusting rx descriptors to %i.\n", rx_descriptors);