Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / drivers / net / ethernet / toshiba / spider_net.c
diff --git a/kernel/drivers/net/ethernet/toshiba/spider_net.c b/kernel/drivers/net/ethernet/toshiba/spider_net.c
new file mode 100644 (file)
index 0000000..8e9371a
--- /dev/null
@@ -0,0 +1,2572 @@
+/*
+ * Network device driver for Cell Processor-Based Blade and Celleb platform
+ *
+ * (C) Copyright IBM Corp. 2005
+ * (C) Copyright 2006 TOSHIBA CORPORATION
+ *
+ * Authors : Utz Bacher <utz.bacher@de.ibm.com>
+ *           Jens Osterkamp <Jens.Osterkamp@de.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/compiler.h>
+#include <linux/crc32.h>
+#include <linux/delay.h>
+#include <linux/etherdevice.h>
+#include <linux/ethtool.h>
+#include <linux/firmware.h>
+#include <linux/if_vlan.h>
+#include <linux/in.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/gfp.h>
+#include <linux/ioport.h>
+#include <linux/ip.h>
+#include <linux/kernel.h>
+#include <linux/mii.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <linux/device.h>
+#include <linux/pci.h>
+#include <linux/skbuff.h>
+#include <linux/tcp.h>
+#include <linux/types.h>
+#include <linux/vmalloc.h>
+#include <linux/wait.h>
+#include <linux/workqueue.h>
+#include <linux/bitops.h>
+#include <asm/pci-bridge.h>
+#include <net/checksum.h>
+
+#include "spider_net.h"
+
+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);
+MODULE_FIRMWARE(SPIDER_NET_FIRMWARE_NAME);
+
+static int rx_descriptors = SPIDER_NET_RX_DESCRIPTORS_DEFAULT;
+static int tx_descriptors = SPIDER_NET_TX_DESCRIPTORS_DEFAULT;
+
+module_param(rx_descriptors, int, 0444);
+module_param(tx_descriptors, int, 0444);
+
+MODULE_PARM_DESC(rx_descriptors, "number of descriptors used " \
+                "in rx chains");
+MODULE_PARM_DESC(tx_descriptors, "number of descriptors used " \
+                "in tx chain");
+
+char spider_net_driver_name[] = "spidernet";
+
+static const struct pci_device_id spider_net_pci_tbl[] = {
+       { PCI_VENDOR_ID_TOSHIBA_2, PCI_DEVICE_ID_TOSHIBA_SPIDER_NET,
+         PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0UL },
+       { 0, }
+};
+
+MODULE_DEVICE_TABLE(pci, spider_net_pci_tbl);
+
+/**
+ * spider_net_read_reg - reads an SMMIO register of a card
+ * @card: device structure
+ * @reg: register to read from
+ *
+ * returns the content of the specified SMMIO register.
+ */
+static inline u32
+spider_net_read_reg(struct spider_net_card *card, u32 reg)
+{
+       /* 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);
+}
+
+/**
+ * spider_net_write_reg - writes to an SMMIO register of a card
+ * @card: device structure
+ * @reg: register to write to
+ * @value: value to write into the specified SMMIO register
+ */
+static inline void
+spider_net_write_reg(struct spider_net_card *card, u32 reg, u32 value)
+{
+       /* 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
+ * @netdev: adapter to be written to
+ * @mii_id: id of MII
+ * @reg: PHY register
+ * @val: value to be written to phy register
+ *
+ * spider_net_write_phy_register writes to an arbitrary PHY
+ * register via the spider GPCWOPCMD register. We assume the queue does
+ * not run full (not more than 15 commands outstanding).
+ **/
+static void
+spider_net_write_phy(struct net_device *netdev, int mii_id,
+                    int reg, int val)
+{
+       struct spider_net_card *card = netdev_priv(netdev);
+       u32 writevalue;
+
+       writevalue = ((u32)mii_id << 21) |
+               ((u32)reg << 16) | ((u32)val);
+
+       spider_net_write_reg(card, SPIDER_NET_GPCWOPCMD, writevalue);
+}
+
+/**
+ * spider_net_read_phy - read from phy register
+ * @netdev: network device to be read from
+ * @mii_id: id of MII
+ * @reg: PHY register
+ *
+ * Returns value read from PHY register
+ *
+ * spider_net_write_phy reads from an arbitrary PHY
+ * register via the spider GPCROPCMD register
+ **/
+static int
+spider_net_read_phy(struct net_device *netdev, int mii_id, int reg)
+{
+       struct spider_net_card *card = netdev_priv(netdev);
+       u32 readvalue;
+
+       readvalue = ((u32)mii_id << 21) | ((u32)reg << 16);
+       spider_net_write_reg(card, SPIDER_NET_GPCROPCMD, readvalue);
+
+       /* we don't use semaphores to wait for an SPIDER_NET_GPROPCMPINT
+        * interrupt, as we poll for the completion of the read operation
+        * in spider_net_read_phy. Should take about 50 us */
+       do {
+               readvalue = spider_net_read_reg(card, SPIDER_NET_GPCROPCMD);
+       } while (readvalue & SPIDER_NET_GPREXEC);
+
+       readvalue &= SPIDER_NET_GPRDAT_MASK;
+
+       return readvalue;
+}
+
+/**
+ * spider_net_setup_aneg - initial auto-negotiation setup
+ * @card: device structure
+ **/
+static void
+spider_net_setup_aneg(struct spider_net_card *card)
+{
+       struct mii_phy *phy = &card->phy;
+       u32 advertise = 0;
+       u16 bmsr, estat;
+
+       bmsr  = spider_net_read_phy(card->netdev, phy->mii_id, MII_BMSR);
+       estat = spider_net_read_phy(card->netdev, phy->mii_id, MII_ESTATUS);
+
+       if (bmsr & BMSR_10HALF)
+               advertise |= ADVERTISED_10baseT_Half;
+       if (bmsr & BMSR_10FULL)
+               advertise |= ADVERTISED_10baseT_Full;
+       if (bmsr & BMSR_100HALF)
+               advertise |= ADVERTISED_100baseT_Half;
+       if (bmsr & BMSR_100FULL)
+               advertise |= ADVERTISED_100baseT_Full;
+
+       if ((bmsr & BMSR_ESTATEN) && (estat & ESTATUS_1000_TFULL))
+               advertise |= SUPPORTED_1000baseT_Full;
+       if ((bmsr & BMSR_ESTATEN) && (estat & ESTATUS_1000_THALF))
+               advertise |= SUPPORTED_1000baseT_Half;
+
+       sungem_phy_probe(phy, phy->mii_id);
+       phy->def->ops->setup_aneg(phy, advertise);
+
+}
+
+/**
+ * spider_net_rx_irq_off - switch off rx irq on this spider card
+ * @card: device structure
+ *
+ * switches off rx irq by masking them out in the GHIINTnMSK register
+ */
+static void
+spider_net_rx_irq_off(struct spider_net_card *card)
+{
+       u32 regvalue;
+
+       regvalue = SPIDER_NET_INT0_MASK_VALUE & (~SPIDER_NET_RXINT);
+       spider_net_write_reg(card, SPIDER_NET_GHIINT0MSK, regvalue);
+}
+
+/**
+ * spider_net_rx_irq_on - switch on rx irq on this spider card
+ * @card: device structure
+ *
+ * switches on rx irq by enabling them in the GHIINTnMSK register
+ */
+static void
+spider_net_rx_irq_on(struct spider_net_card *card)
+{
+       u32 regvalue;
+
+       regvalue = SPIDER_NET_INT0_MASK_VALUE | SPIDER_NET_RXINT;
+       spider_net_write_reg(card, SPIDER_NET_GHIINT0MSK, regvalue);
+}
+
+/**
+ * spider_net_set_promisc - sets the unicast address or the promiscuous mode
+ * @card: card structure
+ *
+ * spider_net_set_promisc sets the unicast destination address filter and
+ * thus either allows for non-promisc mode or promisc mode
+ */
+static void
+spider_net_set_promisc(struct spider_net_card *card)
+{
+       u32 macu, macl;
+       struct net_device *netdev = card->netdev;
+
+       if (netdev->flags & IFF_PROMISC) {
+               /* clear destination entry 0 */
+               spider_net_write_reg(card, SPIDER_NET_GMRUAFILnR, 0);
+               spider_net_write_reg(card, SPIDER_NET_GMRUAFILnR + 0x04, 0);
+               spider_net_write_reg(card, SPIDER_NET_GMRUA0FIL15R,
+                                    SPIDER_NET_PROMISC_VALUE);
+       } else {
+               macu = netdev->dev_addr[0];
+               macu <<= 8;
+               macu |= netdev->dev_addr[1];
+               memcpy(&macl, &netdev->dev_addr[2], sizeof(macl));
+
+               macu |= SPIDER_NET_UA_DESCR_VALUE;
+               spider_net_write_reg(card, SPIDER_NET_GMRUAFILnR, macu);
+               spider_net_write_reg(card, SPIDER_NET_GMRUAFILnR + 0x04, macl);
+               spider_net_write_reg(card, SPIDER_NET_GMRUA0FIL15R,
+                                    SPIDER_NET_NONPROMISC_VALUE);
+       }
+}
+
+/**
+ * spider_net_get_descr_status -- returns the status of a descriptor
+ * @descr: descriptor to look at
+ *
+ * returns the status as in the dmac_cmd_status field of the descriptor
+ */
+static inline int
+spider_net_get_descr_status(struct spider_net_hw_descr *hwdescr)
+{
+       return hwdescr->dmac_cmd_status & SPIDER_NET_DESCR_IND_PROC_MASK;
+}
+
+/**
+ * spider_net_free_chain - free descriptor chain
+ * @card: card structure
+ * @chain: address of chain
+ *
+ */
+static void
+spider_net_free_chain(struct spider_net_card *card,
+                     struct spider_net_descr_chain *chain)
+{
+       struct spider_net_descr *descr;
+
+       descr = chain->ring;
+       do {
+               descr->bus_addr = 0;
+               descr->hwdescr->next_descr_addr = 0;
+               descr = descr->next;
+       } while (descr != chain->ring);
+
+       dma_free_coherent(&card->pdev->dev, chain->num_desc,
+           chain->hwring, chain->dma_addr);
+}
+
+/**
+ * spider_net_init_chain - alloc and link descriptor chain
+ * @card: card structure
+ * @chain: address of chain
+ *
+ * We manage a circular list that mirrors the hardware structure,
+ * except that the hardware uses bus addresses.
+ *
+ * Returns 0 on success, <0 on failure
+ */
+static int
+spider_net_init_chain(struct spider_net_card *card,
+                      struct spider_net_descr_chain *chain)
+{
+       int i;
+       struct spider_net_descr *descr;
+       struct spider_net_hw_descr *hwdescr;
+       dma_addr_t buf;
+       size_t alloc_size;
+
+       alloc_size = chain->num_desc * sizeof(struct spider_net_hw_descr);
+
+       chain->hwring = dma_alloc_coherent(&card->pdev->dev, alloc_size,
+                                          &chain->dma_addr, GFP_KERNEL);
+       if (!chain->hwring)
+               return -ENOMEM;
+
+       memset(chain->ring, 0, chain->num_desc * sizeof(struct spider_net_descr));
+
+       /* Set up the hardware pointers in each descriptor */
+       descr = chain->ring;
+       hwdescr = chain->hwring;
+       buf = chain->dma_addr;
+       for (i=0; i < chain->num_desc; i++, descr++, hwdescr++) {
+               hwdescr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
+               hwdescr->next_descr_addr = 0;
+
+               descr->hwdescr = hwdescr;
+               descr->bus_addr = buf;
+               descr->next = descr + 1;
+               descr->prev = descr - 1;
+
+               buf += sizeof(struct spider_net_hw_descr);
+       }
+       /* do actual circular list */
+       (descr-1)->next = chain->ring;
+       chain->ring->prev = descr-1;
+
+       spin_lock_init(&chain->lock);
+       chain->head = chain->ring;
+       chain->tail = chain->ring;
+       return 0;
+}
+
+/**
+ * spider_net_free_rx_chain_contents - frees descr contents in rx chain
+ * @card: card structure
+ *
+ * returns 0 on success, <0 on failure
+ */
+static void
+spider_net_free_rx_chain_contents(struct spider_net_card *card)
+{
+       struct spider_net_descr *descr;
+
+       descr = card->rx_chain.head;
+       do {
+               if (descr->skb) {
+                       pci_unmap_single(card->pdev, descr->hwdescr->buf_addr,
+                                        SPIDER_NET_MAX_FRAME,
+                                        PCI_DMA_BIDIRECTIONAL);
+                       dev_kfree_skb(descr->skb);
+                       descr->skb = NULL;
+               }
+               descr = descr->next;
+       } while (descr != card->rx_chain.head);
+}
+
+/**
+ * spider_net_prepare_rx_descr - Reinitialize RX descriptor
+ * @card: card structure
+ * @descr: descriptor to re-init
+ *
+ * Return 0 on success, <0 on failure.
+ *
+ * Allocates a new rx skb, iommu-maps it and attaches it to the
+ * descriptor. Mark the descriptor as activated, ready-to-use.
+ */
+static int
+spider_net_prepare_rx_descr(struct spider_net_card *card,
+                           struct spider_net_descr *descr)
+{
+       struct spider_net_hw_descr *hwdescr = descr->hwdescr;
+       dma_addr_t buf;
+       int offset;
+       int bufsize;
+
+       /* we need to round up the buffer size to a multiple of 128 */
+       bufsize = (SPIDER_NET_MAX_FRAME + SPIDER_NET_RXBUF_ALIGN - 1) &
+               (~(SPIDER_NET_RXBUF_ALIGN - 1));
+
+       /* and we need to have it 128 byte aligned, therefore we allocate a
+        * bit more */
+       /* allocate an skb */
+       descr->skb = netdev_alloc_skb(card->netdev,
+                                     bufsize + SPIDER_NET_RXBUF_ALIGN - 1);
+       if (!descr->skb) {
+               if (netif_msg_rx_err(card) && net_ratelimit())
+                       dev_err(&card->netdev->dev,
+                               "Not enough memory to allocate rx buffer\n");
+               card->spider_stats.alloc_rx_skb_error++;
+               return -ENOMEM;
+       }
+       hwdescr->buf_size = bufsize;
+       hwdescr->result_size = 0;
+       hwdescr->valid_size = 0;
+       hwdescr->data_status = 0;
+       hwdescr->data_error = 0;
+
+       offset = ((unsigned long)descr->skb->data) &
+               (SPIDER_NET_RXBUF_ALIGN - 1);
+       if (offset)
+               skb_reserve(descr->skb, SPIDER_NET_RXBUF_ALIGN - offset);
+       /* iommu-map the skb */
+       buf = pci_map_single(card->pdev, descr->skb->data,
+                       SPIDER_NET_MAX_FRAME, PCI_DMA_FROMDEVICE);
+       if (pci_dma_mapping_error(card->pdev, buf)) {
+               dev_kfree_skb_any(descr->skb);
+               descr->skb = NULL;
+               if (netif_msg_rx_err(card) && net_ratelimit())
+                       dev_err(&card->netdev->dev, "Could not iommu-map rx buffer\n");
+               card->spider_stats.rx_iommu_map_error++;
+               hwdescr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
+       } else {
+               hwdescr->buf_addr = buf;
+               wmb();
+               hwdescr->dmac_cmd_status = SPIDER_NET_DESCR_CARDOWNED |
+                                        SPIDER_NET_DMAC_NOINTR_COMPLETE;
+       }
+
+       return 0;
+}
+
+/**
+ * spider_net_enable_rxchtails - sets RX dmac chain tail addresses
+ * @card: card structure
+ *
+ * spider_net_enable_rxchtails sets the RX DMAC chain tail addresses in the
+ * chip by writing to the appropriate register. DMA is enabled in
+ * spider_net_enable_rxdmac.
+ */
+static inline void
+spider_net_enable_rxchtails(struct spider_net_card *card)
+{
+       /* assume chain is aligned correctly */
+       spider_net_write_reg(card, SPIDER_NET_GDADCHA ,
+                            card->rx_chain.tail->bus_addr);
+}
+
+/**
+ * spider_net_enable_rxdmac - enables a receive DMA controller
+ * @card: card structure
+ *
+ * spider_net_enable_rxdmac enables the DMA controller by setting RX_DMA_EN
+ * in the GDADMACCNTR register
+ */
+static inline void
+spider_net_enable_rxdmac(struct spider_net_card *card)
+{
+       wmb();
+       spider_net_write_reg(card, SPIDER_NET_GDADMACCNTR,
+                            SPIDER_NET_DMA_RX_VALUE);
+}
+
+/**
+ * spider_net_disable_rxdmac - disables the receive DMA controller
+ * @card: card structure
+ *
+ * spider_net_disable_rxdmac terminates processing on the DMA controller
+ * by turing off the DMA controller, with the force-end flag set.
+ */
+static inline void
+spider_net_disable_rxdmac(struct spider_net_card *card)
+{
+       spider_net_write_reg(card, SPIDER_NET_GDADMACCNTR,
+                            SPIDER_NET_DMA_RX_FEND_VALUE);
+}
+
+/**
+ * spider_net_refill_rx_chain - refills descriptors/skbs in the rx chains
+ * @card: card structure
+ *
+ * refills descriptors in the rx chain: allocates skbs and iommu-maps them.
+ */
+static void
+spider_net_refill_rx_chain(struct spider_net_card *card)
+{
+       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 (!spin_trylock_irqsave(&chain->lock, flags))
+               return;
+
+       while (spider_net_get_descr_status(chain->head->hwdescr) ==
+                       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);
+}
+
+/**
+ * spider_net_alloc_rx_skbs - Allocates rx skbs in rx descriptor chains
+ * @card: card structure
+ *
+ * Returns 0 on success, <0 on failure.
+ */
+static int
+spider_net_alloc_rx_skbs(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;
+
+       /* Link up the hardware chain pointers */
+       do {
+               descr->prev->hwdescr->next_descr_addr = descr->bus_addr;
+               descr = descr->next;
+       } while (descr != start);
+
+       /* Put at least one buffer into the chain. if this fails,
+        * we've got a problem. If not, spider_net_refill_rx_chain
+        * will do the rest at the end of this function. */
+       if (spider_net_prepare_rx_descr(card, chain->head))
+               goto error;
+       else
+               chain->head = chain->head->next;
+
+       /* This will allocate the rest of the rx buffers;
+        * if not, it's business as usual later on. */
+       spider_net_refill_rx_chain(card);
+       spider_net_enable_rxdmac(card);
+       return 0;
+
+error:
+       spider_net_free_rx_chain_contents(card);
+       return -ENOMEM;
+}
+
+/**
+ * spider_net_get_multicast_hash - generates hash for multicast filter table
+ * @addr: multicast address
+ *
+ * returns the hash value.
+ *
+ * spider_net_get_multicast_hash calculates a hash value for a given multicast
+ * address, that is used to set the multicast filter tables
+ */
+static u8
+spider_net_get_multicast_hash(struct net_device *netdev, __u8 *addr)
+{
+       u32 crc;
+       u8 hash;
+       char addr_for_crc[ETH_ALEN] = { 0, };
+       int i, bit;
+
+       for (i = 0; i < ETH_ALEN * 8; i++) {
+               bit = (addr[i / 8] >> (i % 8)) & 1;
+               addr_for_crc[ETH_ALEN - 1 - i / 8] += bit << (7 - (i % 8));
+       }
+
+       crc = crc32_be(~0, addr_for_crc, netdev->addr_len);
+
+       hash = (crc >> 27);
+       hash <<= 3;
+       hash |= crc & 7;
+       hash &= 0xff;
+
+       return hash;
+}
+
+/**
+ * spider_net_set_multi - sets multicast addresses and promisc flags
+ * @netdev: interface device structure
+ *
+ * spider_net_set_multi configures multicast addresses as needed for the
+ * netdev interface. It also sets up multicast, allmulti and promisc
+ * flags appropriately
+ */
+static void
+spider_net_set_multi(struct net_device *netdev)
+{
+       struct netdev_hw_addr *ha;
+       u8 hash;
+       int i;
+       u32 reg;
+       struct spider_net_card *card = netdev_priv(netdev);
+       unsigned long bitmask[SPIDER_NET_MULTICAST_HASHES / BITS_PER_LONG] =
+               {0, };
+
+       spider_net_set_promisc(card);
+
+       if (netdev->flags & IFF_ALLMULTI) {
+               for (i = 0; i < SPIDER_NET_MULTICAST_HASHES; i++) {
+                       set_bit(i, bitmask);
+               }
+               goto write_hash;
+       }
+
+       /* well, we know, what the broadcast hash value is: it's xfd
+       hash = spider_net_get_multicast_hash(netdev, netdev->broadcast); */
+       set_bit(0xfd, bitmask);
+
+       netdev_for_each_mc_addr(ha, netdev) {
+               hash = spider_net_get_multicast_hash(netdev, ha->addr);
+               set_bit(hash, bitmask);
+       }
+
+write_hash:
+       for (i = 0; i < SPIDER_NET_MULTICAST_HASHES / 4; i++) {
+               reg = 0;
+               if (test_bit(i * 4, bitmask))
+                       reg += 0x08;
+               reg <<= 8;
+               if (test_bit(i * 4 + 1, bitmask))
+                       reg += 0x08;
+               reg <<= 8;
+               if (test_bit(i * 4 + 2, bitmask))
+                       reg += 0x08;
+               reg <<= 8;
+               if (test_bit(i * 4 + 3, bitmask))
+                       reg += 0x08;
+
+               spider_net_write_reg(card, SPIDER_NET_GMRMHFILnR + i * 4, reg);
+       }
+}
+
+/**
+ * spider_net_prepare_tx_descr - fill tx descriptor with skb data
+ * @card: card structure
+ * @skb: packet to use
+ *
+ * returns 0 on success, <0 on failure.
+ *
+ * fills out the descriptor structure with skb data and len. Copies data,
+ * if needed (32bit DMA!)
+ */
+static int
+spider_net_prepare_tx_descr(struct spider_net_card *card,
+                           struct sk_buff *skb)
+{
+       struct spider_net_descr_chain *chain = &card->tx_chain;
+       struct spider_net_descr *descr;
+       struct spider_net_hw_descr *hwdescr;
+       dma_addr_t buf;
+       unsigned long flags;
+
+       buf = pci_map_single(card->pdev, skb->data, skb->len, PCI_DMA_TODEVICE);
+       if (pci_dma_mapping_error(card->pdev, buf)) {
+               if (netif_msg_tx_err(card) && net_ratelimit())
+                       dev_err(&card->netdev->dev, "could not iommu-map packet (%p, %i). "
+                                 "Dropping packet\n", skb->data, skb->len);
+               card->spider_stats.tx_iommu_map_error++;
+               return -ENOMEM;
+       }
+
+       spin_lock_irqsave(&chain->lock, flags);
+       descr = card->tx_chain.head;
+       if (descr->next == chain->tail->prev) {
+               spin_unlock_irqrestore(&chain->lock, flags);
+               pci_unmap_single(card->pdev, buf, skb->len, PCI_DMA_TODEVICE);
+               return -ENOMEM;
+       }
+       hwdescr = descr->hwdescr;
+       chain->head = descr->next;
+
+       descr->skb = skb;
+       hwdescr->buf_addr = buf;
+       hwdescr->buf_size = skb->len;
+       hwdescr->next_descr_addr = 0;
+       hwdescr->data_status = 0;
+
+       hwdescr->dmac_cmd_status =
+                       SPIDER_NET_DESCR_CARDOWNED | SPIDER_NET_DMAC_TXFRMTL;
+       spin_unlock_irqrestore(&chain->lock, flags);
+
+       if (skb->ip_summed == CHECKSUM_PARTIAL)
+               switch (ip_hdr(skb)->protocol) {
+               case IPPROTO_TCP:
+                       hwdescr->dmac_cmd_status |= SPIDER_NET_DMAC_TCP;
+                       break;
+               case IPPROTO_UDP:
+                       hwdescr->dmac_cmd_status |= SPIDER_NET_DMAC_UDP;
+                       break;
+               }
+
+       /* Chain the bus address, so that the DMA engine finds this descr. */
+       wmb();
+       descr->prev->hwdescr->next_descr_addr = descr->bus_addr;
+
+       card->netdev->trans_start = jiffies; /* set netdev watchdog timer */
+       return 0;
+}
+
+static int
+spider_net_set_low_watermark(struct spider_net_card *card)
+{
+       struct spider_net_descr *descr = card->tx_chain.tail;
+       struct spider_net_hw_descr *hwdescr;
+       unsigned long flags;
+       int status;
+       int cnt=0;
+       int i;
+
+       /* 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->hwdescr->dmac_cmd_status & SPIDER_NET_DESCR_NOT_IN_USE;
+               if (status == SPIDER_NET_DESCR_NOT_IN_USE)
+                       break;
+               descr = descr->next;
+               cnt++;
+       }
+
+       /* If TX queue is short, don't even bother with interrupts */
+       if (cnt < card->tx_chain.num_desc/4)
+               return cnt;
+
+       /* 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;
+
+       /* Set the new watermark, clear the old watermark */
+       spin_lock_irqsave(&card->tx_chain.lock, flags);
+       descr->hwdescr->dmac_cmd_status |= SPIDER_NET_DESCR_TXDESFLG;
+       if (card->low_watermark && card->low_watermark != descr) {
+               hwdescr = card->low_watermark->hwdescr;
+               hwdescr->dmac_cmd_status =
+                    hwdescr->dmac_cmd_status & ~SPIDER_NET_DESCR_TXDESFLG;
+       }
+       card->low_watermark = descr;
+       spin_unlock_irqrestore(&card->tx_chain.lock, flags);
+       return cnt;
+}
+
+/**
+ * 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 lose initiative.
+ */
+static int
+spider_net_release_tx_chain(struct spider_net_card *card, int brutal)
+{
+       struct net_device *dev = card->netdev;
+       struct spider_net_descr_chain *chain = &card->tx_chain;
+       struct spider_net_descr *descr;
+       struct spider_net_hw_descr *hwdescr;
+       struct sk_buff *skb;
+       u32 buf_addr;
+       unsigned long flags;
+       int status;
+
+       while (1) {
+               spin_lock_irqsave(&chain->lock, flags);
+               if (chain->tail == chain->head) {
+                       spin_unlock_irqrestore(&chain->lock, flags);
+                       return 0;
+               }
+               descr = chain->tail;
+               hwdescr = descr->hwdescr;
+
+               status = spider_net_get_descr_status(hwdescr);
+               switch (status) {
+               case SPIDER_NET_DESCR_COMPLETE:
+                       dev->stats.tx_packets++;
+                       dev->stats.tx_bytes += descr->skb->len;
+                       break;
+
+               case SPIDER_NET_DESCR_CARDOWNED:
+                       if (!brutal) {
+                               spin_unlock_irqrestore(&chain->lock, flags);
+                               return 1;
+                       }
+
+                       /* 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))
+                               dev_err(&card->netdev->dev, "forcing end of tx descriptor "
+                                      "with status x%02x\n", status);
+                       dev->stats.tx_errors++;
+                       break;
+
+               default:
+                       dev->stats.tx_dropped++;
+                       if (!brutal) {
+                               spin_unlock_irqrestore(&chain->lock, flags);
+                               return 1;
+                       }
+               }
+
+               chain->tail = descr->next;
+               hwdescr->dmac_cmd_status |= SPIDER_NET_DESCR_NOT_IN_USE;
+               skb = descr->skb;
+               descr->skb = NULL;
+               buf_addr = hwdescr->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_consume_skb_any(skb);
+               }
+       }
+       return 0;
+}
+
+/**
+ * spider_net_kick_tx_dma - enables TX DMA processing
+ * @card: card structure
+ *
+ * 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 inline void
+spider_net_kick_tx_dma(struct spider_net_card *card)
+{
+       struct spider_net_descr *descr;
+
+       if (spider_net_read_reg(card, SPIDER_NET_GDTDMACCNTR) &
+                       SPIDER_NET_TX_DMA_EN)
+               goto out;
+
+       descr = card->tx_chain.tail;
+       for (;;) {
+               if (spider_net_get_descr_status(descr->hwdescr) ==
+                               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);
+}
+
+/**
+ * spider_net_xmit - transmits a frame over the device
+ * @skb: packet to send out
+ * @netdev: interface device structure
+ *
+ * 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);
+
+       spider_net_release_tx_chain(card, 0);
+
+       if (spider_net_prepare_tx_descr(card, skb) != 0) {
+               netdev->stats.tx_dropped++;
+               netif_stop_queue(netdev);
+               return NETDEV_TX_BUSY;
+       }
+
+       cnt = spider_net_set_low_watermark(card);
+       if (cnt < 5)
+               spider_net_kick_tx_dma(card);
+       return NETDEV_TX_OK;
+}
+
+/**
+ * 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);
+       }
+}
+
+/**
+ * spider_net_do_ioctl - called for device ioctls
+ * @netdev: interface device structure
+ * @ifr: request parameter structure for ioctl
+ * @cmd: command code for ioctl
+ *
+ * returns 0 on success, <0 on failure. Currently, we have no special ioctls.
+ * -EOPNOTSUPP is returned, if an unknown ioctl was requested
+ */
+static int
+spider_net_do_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
+{
+       switch (cmd) {
+       default:
+               return -EOPNOTSUPP;
+       }
+}
+
+/**
+ * spider_net_pass_skb_up - takes an skb from a descriptor and passes it on
+ * @descr: descriptor to process
+ * @card: card structure
+ *
+ * Fills out skb structure and passes the data to the stack.
+ * The descriptor state is not changed.
+ */
+static void
+spider_net_pass_skb_up(struct spider_net_descr *descr,
+                      struct spider_net_card *card)
+{
+       struct spider_net_hw_descr *hwdescr = descr->hwdescr;
+       struct sk_buff *skb = descr->skb;
+       struct net_device *netdev = card->netdev;
+       u32 data_status = hwdescr->data_status;
+       u32 data_error = hwdescr->data_error;
+
+       skb_put(skb, hwdescr->valid_size);
+
+       /* the card seems to add 2 bytes of junk in front
+        * of the ethernet frame */
+#define SPIDER_MISALIGN                2
+       skb_pull(skb, SPIDER_MISALIGN);
+       skb->protocol = eth_type_trans(skb, netdev);
+
+       /* checksum offload */
+       skb_checksum_none_assert(skb);
+       if (netdev->features & NETIF_F_RXCSUM) {
+               if ( ( (data_status & SPIDER_NET_DATA_STATUS_CKSUM_MASK) ==
+                      SPIDER_NET_DATA_STATUS_CKSUM_MASK) &&
+                    !(data_error & SPIDER_NET_DATA_ERR_CKSUM_MASK))
+                       skb->ip_summed = CHECKSUM_UNNECESSARY;
+       }
+
+       if (data_status & SPIDER_NET_VLAN_PACKET) {
+               /* further enhancements: HW-accel VLAN */
+       }
+
+       /* update netdevice statistics */
+       netdev->stats.rx_packets++;
+       netdev->stats.rx_bytes += skb->len;
+
+       /* pass skb up to stack */
+       netif_receive_skb(skb);
+}
+
+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 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
+       {
+               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) {
+                       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);
+#endif
+
+}
+
+/**
+ * spider_net_resync_head_ptr - Advance head ptr past empty descrs
+ *
+ * If the driver fails to keep up and empty the queue, then the
+ * hardware wil run out of room to put incoming packets. This
+ * will cause the hardware to skip descrs that are full (instead
+ * of halting/retrying). Thus, once the driver runs, it wil need
+ * to "catch up" to where the hardware chain pointer is at.
+ */
+static void spider_net_resync_head_ptr(struct spider_net_card *card)
+{
+       unsigned long flags;
+       struct spider_net_descr_chain *chain = &card->rx_chain;
+       struct spider_net_descr *descr;
+       int i, status;
+
+       /* Advance head pointer past any empty descrs */
+       descr = chain->head;
+       status = spider_net_get_descr_status(descr->hwdescr);
+
+       if (status == SPIDER_NET_DESCR_NOT_IN_USE)
+               return;
+
+       spin_lock_irqsave(&chain->lock, flags);
+
+       descr = chain->head;
+       status = spider_net_get_descr_status(descr->hwdescr);
+       for (i=0; i<chain->num_desc; i++) {
+               if (status != SPIDER_NET_DESCR_CARDOWNED) break;
+               descr = descr->next;
+               status = spider_net_get_descr_status(descr->hwdescr);
+       }
+       chain->head = descr;
+
+       spin_unlock_irqrestore(&chain->lock, flags);
+}
+
+static int spider_net_resync_tail_ptr(struct spider_net_card *card)
+{
+       struct spider_net_descr_chain *chain = &card->rx_chain;
+       struct spider_net_descr *descr;
+       int i, status;
+
+       /* Advance tail pointer past any empty and reaped descrs */
+       descr = chain->tail;
+       status = spider_net_get_descr_status(descr->hwdescr);
+
+       for (i=0; i<chain->num_desc; i++) {
+               if ((status != SPIDER_NET_DESCR_CARDOWNED) &&
+                   (status != SPIDER_NET_DESCR_NOT_IN_USE)) break;
+               descr = descr->next;
+               status = spider_net_get_descr_status(descr->hwdescr);
+       }
+       chain->tail = descr;
+
+       if ((i == chain->num_desc) || (i == 0))
+               return 1;
+       return 0;
+}
+
+/**
+ * spider_net_decode_one_descr - processes an RX descriptor
+ * @card: card structure
+ *
+ * Returns 1 if a packet has been sent to the stack, otherwise 0.
+ *
+ * Processes an RX descriptor by iommu-unmapping the data buffer
+ * and passing the packet up to the stack. This function is called
+ * in softirq context, e.g. either bottom half from interrupt or
+ * NAPI polling context.
+ */
+static int
+spider_net_decode_one_descr(struct spider_net_card *card)
+{
+       struct net_device *dev = card->netdev;
+       struct spider_net_descr_chain *chain = &card->rx_chain;
+       struct spider_net_descr *descr = chain->tail;
+       struct spider_net_hw_descr *hwdescr = descr->hwdescr;
+       u32 hw_buf_addr;
+       int status;
+
+       status = spider_net_get_descr_status(hwdescr);
+
+       /* Nothing in the descriptor, or ring must be empty */
+       if ((status == SPIDER_NET_DESCR_CARDOWNED) ||
+           (status == SPIDER_NET_DESCR_NOT_IN_USE))
+               return 0;
+
+       /* descriptor definitively used -- move on tail */
+       chain->tail = descr->next;
+
+       /* unmap descriptor */
+       hw_buf_addr = hwdescr->buf_addr;
+       hwdescr->buf_addr = 0xffffffff;
+       pci_unmap_single(card->pdev, hw_buf_addr,
+                       SPIDER_NET_MAX_FRAME, PCI_DMA_FROMDEVICE);
+
+       if ( (status == SPIDER_NET_DESCR_RESPONSE_ERROR) ||
+            (status == SPIDER_NET_DESCR_PROTECTION_ERROR) ||
+            (status == SPIDER_NET_DESCR_FORCE_END) ) {
+               if (netif_msg_rx_err(card))
+                       dev_err(&dev->dev,
+                              "dropping RX descriptor with state %d\n", status);
+               dev->stats.rx_dropped++;
+               goto bad_desc;
+       }
+
+       if ( (status != SPIDER_NET_DESCR_COMPLETE) &&
+            (status != SPIDER_NET_DESCR_FRAME_END) ) {
+               if (netif_msg_rx_err(card))
+                       dev_err(&card->netdev->dev,
+                              "RX descriptor with unknown state %d\n", status);
+               card->spider_stats.rx_desc_unk_state++;
+               goto bad_desc;
+       }
+
+       /* The cases we'll throw away the packet immediately */
+       if (hwdescr->data_error & SPIDER_NET_DESTROY_RX_FLAGS) {
+               if (netif_msg_rx_err(card))
+                       dev_err(&card->netdev->dev,
+                              "error in received descriptor found, "
+                              "data_status=x%08x, data_error=x%08x\n",
+                              hwdescr->data_status, hwdescr->data_error);
+               goto bad_desc;
+       }
+
+       if (hwdescr->dmac_cmd_status & SPIDER_NET_DESCR_BAD_STATUS) {
+               dev_err(&card->netdev->dev, "bad status, cmd_status=x%08x\n",
+                              hwdescr->dmac_cmd_status);
+               pr_err("buf_addr=x%08x\n", hw_buf_addr);
+               pr_err("buf_size=x%08x\n", hwdescr->buf_size);
+               pr_err("next_descr_addr=x%08x\n", hwdescr->next_descr_addr);
+               pr_err("result_size=x%08x\n", hwdescr->result_size);
+               pr_err("valid_size=x%08x\n", hwdescr->valid_size);
+               pr_err("data_status=x%08x\n", hwdescr->data_status);
+               pr_err("data_error=x%08x\n", hwdescr->data_error);
+               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->skb = NULL;
+       hwdescr->dmac_cmd_status = SPIDER_NET_DESCR_NOT_IN_USE;
+       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;
+       return 0;
+}
+
+/**
+ * spider_net_poll - NAPI poll function called by the stack to return packets
+ * @netdev: interface device structure
+ * @budget: number of packets we can pass to the stack at most
+ *
+ * returns 0 if no more packets available to the driver/stack. Returns 1,
+ * if the quota is exceeded, but the driver has still packets.
+ *
+ * spider_net_poll returns all packets from the rx descriptors to the stack
+ * (using netif_receive_skb). If all/enough packets are up, the driver
+ * reenables interrupts and returns 0. If not, 1 is returned.
+ */
+static int spider_net_poll(struct napi_struct *napi, int budget)
+{
+       struct spider_net_card *card = container_of(napi, struct spider_net_card, napi);
+       int packets_done = 0;
+
+       while (packets_done < budget) {
+               if (!spider_net_decode_one_descr(card))
+                       break;
+
+               packets_done++;
+       }
+
+       if ((packets_done == 0) && (card->num_rx_ints != 0)) {
+               if (!spider_net_resync_tail_ptr(card))
+                       packets_done = budget;
+               spider_net_resync_head_ptr(card);
+       }
+       card->num_rx_ints = 0;
+
+       spider_net_refill_rx_chain(card);
+       spider_net_enable_rxdmac(card);
+
+       spider_net_cleanup_tx_ring(card);
+
+       /* if all packets are in the stack, enable interrupts and return 0 */
+       /* if not, return 1 */
+       if (packets_done < budget) {
+               napi_complete(napi);
+               spider_net_rx_irq_on(card);
+               card->ignore_rx_ramfull = 0;
+       }
+
+       return packets_done;
+}
+
+/**
+ * spider_net_change_mtu - changes the MTU of an interface
+ * @netdev: interface device structure
+ * @new_mtu: new MTU value
+ *
+ * returns 0 on success, <0 on failure
+ */
+static int
+spider_net_change_mtu(struct net_device *netdev, int new_mtu)
+{
+       /* no need to re-alloc skbs or so -- the max mtu is about 2.3k
+        * and mtu is outbound only anyway */
+       if ( (new_mtu < SPIDER_NET_MIN_MTU ) ||
+               (new_mtu > SPIDER_NET_MAX_MTU) )
+               return -EINVAL;
+       netdev->mtu = new_mtu;
+       return 0;
+}
+
+/**
+ * spider_net_set_mac - sets the MAC of an interface
+ * @netdev: interface device structure
+ * @ptr: pointer to new MAC address
+ *
+ * Returns 0 on success, <0 on failure. Currently, we don't support this
+ * and will always return EOPNOTSUPP.
+ */
+static int
+spider_net_set_mac(struct net_device *netdev, void *p)
+{
+       struct spider_net_card *card = netdev_priv(netdev);
+       u32 macl, macu, regvalue;
+       struct sockaddr *addr = p;
+
+       if (!is_valid_ether_addr(addr->sa_data))
+               return -EADDRNOTAVAIL;
+
+       memcpy(netdev->dev_addr, addr->sa_data, ETH_ALEN);
+
+       /* switch off GMACTPE and GMACRPE */
+       regvalue = spider_net_read_reg(card, SPIDER_NET_GMACOPEMD);
+       regvalue &= ~((1 << 5) | (1 << 6));
+       spider_net_write_reg(card, SPIDER_NET_GMACOPEMD, regvalue);
+
+       /* write mac */
+       macu = (netdev->dev_addr[0]<<24) + (netdev->dev_addr[1]<<16) +
+               (netdev->dev_addr[2]<<8) + (netdev->dev_addr[3]);
+       macl = (netdev->dev_addr[4]<<8) + (netdev->dev_addr[5]);
+       spider_net_write_reg(card, SPIDER_NET_GMACUNIMACU, macu);
+       spider_net_write_reg(card, SPIDER_NET_GMACUNIMACL, macl);
+
+       /* switch GMACTPE and GMACRPE back on */
+       regvalue = spider_net_read_reg(card, SPIDER_NET_GMACOPEMD);
+       regvalue |= ((1 << 5) | (1 << 6));
+       spider_net_write_reg(card, SPIDER_NET_GMACOPEMD, regvalue);
+
+       spider_net_set_promisc(card);
+
+       return 0;
+}
+
+/**
+ * spider_net_link_reset
+ * @netdev: net device structure
+ *
+ * This is called when the PHY_LINK signal is asserted. For the blade this is
+ * not connected so we should never get here.
+ *
+ */
+static void
+spider_net_link_reset(struct net_device *netdev)
+{
+
+       struct spider_net_card *card = netdev_priv(netdev);
+
+       del_timer_sync(&card->aneg_timer);
+
+       /* clear interrupt, block further interrupts */
+       spider_net_write_reg(card, SPIDER_NET_GMACST,
+                            spider_net_read_reg(card, SPIDER_NET_GMACST));
+       spider_net_write_reg(card, SPIDER_NET_GMACINTEN, 0);
+
+       /* reset phy and setup aneg */
+       card->aneg_count = 0;
+       card->medium = BCM54XX_COPPER;
+       spider_net_setup_aneg(card);
+       mod_timer(&card->aneg_timer, jiffies + SPIDER_NET_ANEG_TIMER);
+
+}
+
+/**
+ * spider_net_handle_error_irq - handles errors raised by an interrupt
+ * @card: card structure
+ * @status_reg: interrupt status register 0 (GHIINT0STS)
+ *
+ * spider_net_handle_error_irq treats or ignores all error conditions
+ * found when an interrupt is presented
+ */
+static void
+spider_net_handle_error_irq(struct spider_net_card *card, u32 status_reg,
+                           u32 error_reg1, u32 error_reg2)
+{
+       u32 i;
+       int show_error = 1;
+
+       /* check GHIINT0STS ************************************/
+       if (status_reg)
+               for (i = 0; i < 32; i++)
+                       if (status_reg & (1<<i))
+                               switch (i)
+       {
+       /* let error_reg1 and error_reg2 evaluation decide, what to do
+       case SPIDER_NET_PHYINT:
+       case SPIDER_NET_GMAC2INT:
+       case SPIDER_NET_GMAC1INT:
+       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;
+               break;
+       case SPIDER_NET_GPROPCMPINT:
+               /* PHY read operation completed */
+               /* we don't use semaphores, as we poll for the completion
+                * of the read operation in spider_net_read_phy. Should take
+                * about 50 us */
+               show_error = 0;
+               break;
+       case SPIDER_NET_GPWFFINT:
+               /* PHY command queue full */
+               if (netif_msg_intr(card))
+                       dev_err(&card->netdev->dev, "PHY write queue full\n");
+               show_error = 0;
+               break;
+
+       /* case SPIDER_NET_GRMDADRINT: not used. print a message */
+       /* case SPIDER_NET_GRMARPINT: not used. print a message */
+       /* case SPIDER_NET_GRMMPINT: not used. print a message */
+
+       case SPIDER_NET_GDTDEN0INT:
+               /* someone has set TX_DMA_EN to 0 */
+               show_error = 0;
+               break;
+
+       case SPIDER_NET_GDDDEN0INT: /* fallthrough */
+       case SPIDER_NET_GDCDEN0INT: /* fallthrough */
+       case SPIDER_NET_GDBDEN0INT: /* fallthrough */
+       case SPIDER_NET_GDADEN0INT:
+               /* someone has set RX_DMA_EN to 0 */
+               show_error = 0;
+               break;
+
+       /* RX interrupts */
+       case SPIDER_NET_GDDFDCINT:
+       case SPIDER_NET_GDCFDCINT:
+       case SPIDER_NET_GDBFDCINT:
+       case SPIDER_NET_GDAFDCINT:
+       /* case SPIDER_NET_GDNMINT: not used. print a message */
+       /* case SPIDER_NET_GCNMINT: not used. print a message */
+       /* case SPIDER_NET_GBNMINT: not used. print a message */
+       /* case SPIDER_NET_GANMINT: not used. print a message */
+       /* case SPIDER_NET_GRFNMINT: not used. print a message */
+               show_error = 0;
+               break;
+
+       /* TX interrupts */
+       case SPIDER_NET_GDTFDCINT:
+               show_error = 0;
+               break;
+       case SPIDER_NET_GTTEDINT:
+               show_error = 0;
+               break;
+       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)
+                       spider_net_kick_tx_dma(card);
+               */
+               show_error = 0;
+               break;
+
+       /* case SPIDER_NET_G1TMCNTINT: not used. print a message */
+       /* case SPIDER_NET_GFREECNTINT: not used. print a message */
+       }
+
+       /* check GHIINT1STS ************************************/
+       if (error_reg1)
+               for (i = 0; i < 32; i++)
+                       if (error_reg1 & (1<<i))
+                               switch (i)
+       {
+       case SPIDER_NET_GTMFLLINT:
+               /* TX RAM full may happen on a usual case.
+                * Logging is not needed. */
+               show_error = 0;
+               break;
+       case SPIDER_NET_GRFDFLLINT: /* fallthrough */
+       case SPIDER_NET_GRFCFLLINT: /* fallthrough */
+       case SPIDER_NET_GRFBFLLINT: /* fallthrough */
+       case SPIDER_NET_GRFAFLLINT: /* fallthrough */
+       case SPIDER_NET_GRMFLLINT:
+               /* Could happen when rx chain is full */
+               if (card->ignore_rx_ramfull == 0) {
+                       card->ignore_rx_ramfull = 1;
+                       spider_net_resync_head_ptr(card);
+                       spider_net_refill_rx_chain(card);
+                       spider_net_enable_rxdmac(card);
+                       card->num_rx_ints ++;
+                       napi_schedule(&card->napi);
+               }
+               show_error = 0;
+               break;
+
+       /* case SPIDER_NET_GTMSHTINT: problem, print a message */
+       case SPIDER_NET_GDTINVDINT:
+               /* allrighty. tx from previous descr ok */
+               show_error = 0;
+               break;
+
+       /* chain end */
+       case SPIDER_NET_GDDDCEINT: /* fallthrough */
+       case SPIDER_NET_GDCDCEINT: /* fallthrough */
+       case SPIDER_NET_GDBDCEINT: /* fallthrough */
+       case SPIDER_NET_GDADCEINT:
+               spider_net_resync_head_ptr(card);
+               spider_net_refill_rx_chain(card);
+               spider_net_enable_rxdmac(card);
+               card->num_rx_ints ++;
+               napi_schedule(&card->napi);
+               show_error = 0;
+               break;
+
+       /* invalid descriptor */
+       case SPIDER_NET_GDDINVDINT: /* fallthrough */
+       case SPIDER_NET_GDCINVDINT: /* fallthrough */
+       case SPIDER_NET_GDBINVDINT: /* fallthrough */
+       case SPIDER_NET_GDAINVDINT:
+               /* Could happen when rx chain is full */
+               spider_net_resync_head_ptr(card);
+               spider_net_refill_rx_chain(card);
+               spider_net_enable_rxdmac(card);
+               card->num_rx_ints ++;
+               napi_schedule(&card->napi);
+               show_error = 0;
+               break;
+
+       /* case SPIDER_NET_GDTRSERINT: problem, print a message */
+       /* case SPIDER_NET_GDDRSERINT: problem, print a message */
+       /* case SPIDER_NET_GDCRSERINT: problem, print a message */
+       /* case SPIDER_NET_GDBRSERINT: problem, print a message */
+       /* case SPIDER_NET_GDARSERINT: problem, print a message */
+       /* case SPIDER_NET_GDSERINT: problem, print a message */
+       /* case SPIDER_NET_GDTPTERINT: problem, print a message */
+       /* case SPIDER_NET_GDDPTERINT: problem, print a message */
+       /* case SPIDER_NET_GDCPTERINT: problem, print a message */
+       /* case SPIDER_NET_GDBPTERINT: problem, print a message */
+       /* case SPIDER_NET_GDAPTERINT: problem, print a message */
+       default:
+               show_error = 1;
+               break;
+       }
+
+       /* check GHIINT2STS ************************************/
+       if (error_reg2)
+               for (i = 0; i < 32; i++)
+                       if (error_reg2 & (1<<i))
+                               switch (i)
+       {
+       /* there is nothing we can (want  to) do at this time. Log a
+        * message, we can switch on and off the specific values later on
+       case SPIDER_NET_GPROPERINT:
+       case SPIDER_NET_GMCTCRSNGINT:
+       case SPIDER_NET_GMCTLCOLINT:
+       case SPIDER_NET_GMCTTMOTINT:
+       case SPIDER_NET_GMCRCAERINT:
+       case SPIDER_NET_GMCRCALERINT:
+       case SPIDER_NET_GMCRALNERINT:
+       case SPIDER_NET_GMCROVRINT:
+       case SPIDER_NET_GMCRRNTINT:
+       case SPIDER_NET_GMCRRXERINT:
+       case SPIDER_NET_GTITCSERINT:
+       case SPIDER_NET_GTIFMTERINT:
+       case SPIDER_NET_GTIPKTRVKINT:
+       case SPIDER_NET_GTISPINGINT:
+       case SPIDER_NET_GTISADNGINT:
+       case SPIDER_NET_GTISPDNGINT:
+       case SPIDER_NET_GRIFMTERINT:
+       case SPIDER_NET_GRIPKTRVKINT:
+       case SPIDER_NET_GRISPINGINT:
+       case SPIDER_NET_GRISADNGINT:
+       case SPIDER_NET_GRISPDNGINT:
+               break;
+       */
+               default:
+                       break;
+       }
+
+       if ((show_error) && (netif_msg_intr(card)) && net_ratelimit())
+               dev_err(&card->netdev->dev, "Error interrupt, GHIINT0STS = 0x%08x, "
+                      "GHIINT1STS = 0x%08x, GHIINT2STS = 0x%08x\n",
+                      status_reg, error_reg1, error_reg2);
+
+       /* clear interrupt sources */
+       spider_net_write_reg(card, SPIDER_NET_GHIINT1STS, error_reg1);
+       spider_net_write_reg(card, SPIDER_NET_GHIINT2STS, error_reg2);
+}
+
+/**
+ * spider_net_interrupt - interrupt handler for spider_net
+ * @irq: interrupt number
+ * @ptr: pointer to net_device
+ *
+ * returns IRQ_HANDLED, if interrupt was for driver, or IRQ_NONE, if no
+ * interrupt found raised by card.
+ *
+ * This is the interrupt handler, that turns off
+ * interrupts for this device and makes the stack poll the driver
+ */
+static irqreturn_t
+spider_net_interrupt(int irq, void *ptr)
+{
+       struct net_device *netdev = ptr;
+       struct spider_net_card *card = netdev_priv(netdev);
+       u32 status_reg, error_reg1, error_reg2;
+
+       status_reg = spider_net_read_reg(card, SPIDER_NET_GHIINT0STS);
+       error_reg1 = spider_net_read_reg(card, SPIDER_NET_GHIINT1STS);
+       error_reg2 = spider_net_read_reg(card, SPIDER_NET_GHIINT2STS);
+
+       if (!(status_reg & SPIDER_NET_INT0_MASK_VALUE) &&
+           !(error_reg1 & SPIDER_NET_INT1_MASK_VALUE) &&
+           !(error_reg2 & SPIDER_NET_INT2_MASK_VALUE))
+               return IRQ_NONE;
+
+       if (status_reg & SPIDER_NET_RXINT ) {
+               spider_net_rx_irq_off(card);
+               napi_schedule(&card->napi);
+               card->num_rx_ints ++;
+       }
+       if (status_reg & SPIDER_NET_TXINT)
+               napi_schedule(&card->napi);
+
+       if (status_reg & SPIDER_NET_LINKINT)
+               spider_net_link_reset(netdev);
+
+       if (status_reg & SPIDER_NET_ERRINT )
+               spider_net_handle_error_irq(card, status_reg,
+                                           error_reg1, error_reg2);
+
+       /* clear interrupt sources */
+       spider_net_write_reg(card, SPIDER_NET_GHIINT0STS, status_reg);
+
+       return IRQ_HANDLED;
+}
+
+#ifdef CONFIG_NET_POLL_CONTROLLER
+/**
+ * spider_net_poll_controller - artificial interrupt for netconsole etc.
+ * @netdev: interface device structure
+ *
+ * see Documentation/networking/netconsole.txt
+ */
+static void
+spider_net_poll_controller(struct net_device *netdev)
+{
+       disable_irq(netdev->irq);
+       spider_net_interrupt(netdev->irq, netdev);
+       enable_irq(netdev->irq);
+}
+#endif /* CONFIG_NET_POLL_CONTROLLER */
+
+/**
+ * spider_net_enable_interrupts - enable interrupts
+ * @card: card structure
+ *
+ * spider_net_enable_interrupt enables several interrupts
+ */
+static void
+spider_net_enable_interrupts(struct spider_net_card *card)
+{
+       spider_net_write_reg(card, SPIDER_NET_GHIINT0MSK,
+                            SPIDER_NET_INT0_MASK_VALUE);
+       spider_net_write_reg(card, SPIDER_NET_GHIINT1MSK,
+                            SPIDER_NET_INT1_MASK_VALUE);
+       spider_net_write_reg(card, SPIDER_NET_GHIINT2MSK,
+                            SPIDER_NET_INT2_MASK_VALUE);
+}
+
+/**
+ * spider_net_disable_interrupts - disable interrupts
+ * @card: card structure
+ *
+ * spider_net_disable_interrupts disables all the interrupts
+ */
+static void
+spider_net_disable_interrupts(struct spider_net_card *card)
+{
+       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);
+       spider_net_write_reg(card, SPIDER_NET_GMACINTEN, 0);
+}
+
+/**
+ * spider_net_init_card - initializes the card
+ * @card: card structure
+ *
+ * spider_net_init_card initializes the card so that other registers can
+ * be used
+ */
+static void
+spider_net_init_card(struct spider_net_card *card)
+{
+       spider_net_write_reg(card, SPIDER_NET_CKRCTRL,
+                            SPIDER_NET_CKRCTRL_STOP_VALUE);
+
+       spider_net_write_reg(card, SPIDER_NET_CKRCTRL,
+                            SPIDER_NET_CKRCTRL_RUN_VALUE);
+
+       /* trigger ETOMOD signal */
+       spider_net_write_reg(card, SPIDER_NET_GMACOPEMD,
+               spider_net_read_reg(card, SPIDER_NET_GMACOPEMD) | 0x4);
+
+       spider_net_disable_interrupts(card);
+}
+
+/**
+ * spider_net_enable_card - enables the card by setting all kinds of regs
+ * @card: card structure
+ *
+ * spider_net_enable_card sets a lot of SMMIO registers to enable the device
+ */
+static void
+spider_net_enable_card(struct spider_net_card *card)
+{
+       int i;
+       /* the following array consists of (register),(value) pairs
+        * that are set in this function. A register of 0 ends the list */
+       u32 regs[][2] = {
+               { SPIDER_NET_GRESUMINTNUM, 0 },
+               { SPIDER_NET_GREINTNUM, 0 },
+
+               /* set interrupt frame number registers */
+               /* clear the single DMA engine registers first */
+               { SPIDER_NET_GFAFRMNUM, SPIDER_NET_GFXFRAMES_VALUE },
+               { SPIDER_NET_GFBFRMNUM, SPIDER_NET_GFXFRAMES_VALUE },
+               { SPIDER_NET_GFCFRMNUM, SPIDER_NET_GFXFRAMES_VALUE },
+               { SPIDER_NET_GFDFRMNUM, SPIDER_NET_GFXFRAMES_VALUE },
+               /* then set, what we really need */
+               { SPIDER_NET_GFFRMNUM, SPIDER_NET_FRAMENUM_VALUE },
+
+               /* timer counter registers and stuff */
+               { SPIDER_NET_GFREECNNUM, 0 },
+               { SPIDER_NET_GONETIMENUM, 0 },
+               { SPIDER_NET_GTOUTFRMNUM, 0 },
+
+               /* RX mode setting */
+               { SPIDER_NET_GRXMDSET, SPIDER_NET_RXMODE_VALUE },
+               /* TX mode setting */
+               { SPIDER_NET_GTXMDSET, SPIDER_NET_TXMODE_VALUE },
+               /* IPSEC mode setting */
+               { SPIDER_NET_GIPSECINIT, SPIDER_NET_IPSECINIT_VALUE },
+
+               { SPIDER_NET_GFTRESTRT, SPIDER_NET_RESTART_VALUE },
+
+               { SPIDER_NET_GMRWOLCTRL, 0 },
+               { SPIDER_NET_GTESTMD, 0x10000000 },
+               { SPIDER_NET_GTTQMSK, 0x00400040 },
+
+               { SPIDER_NET_GMACINTEN, 0 },
+
+               /* flow control stuff */
+               { SPIDER_NET_GMACAPAUSE, SPIDER_NET_MACAPAUSE_VALUE },
+               { SPIDER_NET_GMACTXPAUSE, SPIDER_NET_TXPAUSE_VALUE },
+
+               { SPIDER_NET_GMACBSTLMT, SPIDER_NET_BURSTLMT_VALUE },
+               { 0, 0}
+       };
+
+       i = 0;
+       while (regs[i][0]) {
+               spider_net_write_reg(card, regs[i][0], regs[i][1]);
+               i++;
+       }
+
+       /* clear unicast filter table entries 1 to 14 */
+       for (i = 1; i <= 14; i++) {
+               spider_net_write_reg(card,
+                                    SPIDER_NET_GMRUAFILnR + i * 8,
+                                    0x00080000);
+               spider_net_write_reg(card,
+                                    SPIDER_NET_GMRUAFILnR + i * 8 + 4,
+                                    0x00000000);
+       }
+
+       spider_net_write_reg(card, SPIDER_NET_GMRUA0FIL15R, 0x08080000);
+
+       spider_net_write_reg(card, SPIDER_NET_ECMODE, SPIDER_NET_ECMODE_VALUE);
+
+       /* set chain tail address for RX chains and
+        * enable DMA */
+       spider_net_enable_rxchtails(card);
+       spider_net_enable_rxdmac(card);
+
+       spider_net_write_reg(card, SPIDER_NET_GRXDMAEN, SPIDER_NET_WOL_VALUE);
+
+       spider_net_write_reg(card, SPIDER_NET_GMACLENLMT,
+                            SPIDER_NET_LENLMT_VALUE);
+       spider_net_write_reg(card, SPIDER_NET_GMACOPEMD,
+                            SPIDER_NET_OPMODE_VALUE);
+
+       spider_net_write_reg(card, SPIDER_NET_GDTDMACCNTR,
+                            SPIDER_NET_GDTBSTA);
+}
+
+/**
+ * spider_net_download_firmware - loads firmware into the adapter
+ * @card: card structure
+ * @firmware_ptr: pointer to firmware data
+ *
+ * spider_net_download_firmware loads the firmware data into the
+ * adapter. It assumes the length etc. to be allright.
+ */
+static int
+spider_net_download_firmware(struct spider_net_card *card,
+                            const void *firmware_ptr)
+{
+       int sequencer, i;
+       const u32 *fw_ptr = firmware_ptr;
+
+       /* stop sequencers */
+       spider_net_write_reg(card, SPIDER_NET_GSINIT,
+                            SPIDER_NET_STOP_SEQ_VALUE);
+
+       for (sequencer = 0; sequencer < SPIDER_NET_FIRMWARE_SEQS;
+            sequencer++) {
+               spider_net_write_reg(card,
+                                    SPIDER_NET_GSnPRGADR + sequencer * 8, 0);
+               for (i = 0; i < SPIDER_NET_FIRMWARE_SEQWORDS; i++) {
+                       spider_net_write_reg(card, SPIDER_NET_GSnPRGDAT +
+                                            sequencer * 8, *fw_ptr);
+                       fw_ptr++;
+               }
+       }
+
+       if (spider_net_read_reg(card, SPIDER_NET_GSINIT))
+               return -EIO;
+
+       spider_net_write_reg(card, SPIDER_NET_GSINIT,
+                            SPIDER_NET_RUN_SEQ_VALUE);
+
+       return 0;
+}
+
+/**
+ * spider_net_init_firmware - reads in firmware parts
+ * @card: card structure
+ *
+ * Returns 0 on success, <0 on failure
+ *
+ * spider_net_init_firmware opens the sequencer firmware and does some basic
+ * checks. This function opens and releases the firmware structure. A call
+ * to download the firmware is performed before the release.
+ *
+ * Firmware format
+ * ===============
+ * spider_fw.bin is expected to be a file containing 6*1024*4 bytes, 4k being
+ * the program for each sequencer. Use the command
+ *    tail -q -n +2 Seq_code1_0x088.txt Seq_code2_0x090.txt              \
+ *         Seq_code3_0x098.txt Seq_code4_0x0A0.txt Seq_code5_0x0A8.txt   \
+ *         Seq_code6_0x0B0.txt | xxd -r -p -c4 > spider_fw.bin
+ *
+ * to generate spider_fw.bin, if you have sequencer programs with something
+ * like the following contents for each sequencer:
+ *    <ONE LINE COMMENT>
+ *    <FIRST 4-BYTES-WORD FOR SEQUENCER>
+ *    <SECOND 4-BYTES-WORD FOR SEQUENCER>
+ *     ...
+ *    <1024th 4-BYTES-WORD FOR SEQUENCER>
+ */
+static int
+spider_net_init_firmware(struct spider_net_card *card)
+{
+       struct firmware *firmware = NULL;
+       struct device_node *dn;
+       const u8 *fw_prop = NULL;
+       int err = -ENOENT;
+       int fw_size;
+
+       if (request_firmware((const struct firmware **)&firmware,
+                            SPIDER_NET_FIRMWARE_NAME, &card->pdev->dev) == 0) {
+               if ( (firmware->size != SPIDER_NET_FIRMWARE_LEN) &&
+                    netif_msg_probe(card) ) {
+                       dev_err(&card->netdev->dev,
+                              "Incorrect size of spidernet firmware in " \
+                              "filesystem. Looking in host firmware...\n");
+                       goto try_host_fw;
+               }
+               err = spider_net_download_firmware(card, firmware->data);
+
+               release_firmware(firmware);
+               if (err)
+                       goto try_host_fw;
+
+               goto done;
+       }
+
+try_host_fw:
+       dn = pci_device_to_OF_node(card->pdev);
+       if (!dn)
+               goto out_err;
+
+       fw_prop = of_get_property(dn, "firmware", &fw_size);
+       if (!fw_prop)
+               goto out_err;
+
+       if ( (fw_size != SPIDER_NET_FIRMWARE_LEN) &&
+            netif_msg_probe(card) ) {
+               dev_err(&card->netdev->dev,
+                      "Incorrect size of spidernet firmware in host firmware\n");
+               goto done;
+       }
+
+       err = spider_net_download_firmware(card, fw_prop);
+
+done:
+       return err;
+out_err:
+       if (netif_msg_probe(card))
+               dev_err(&card->netdev->dev,
+                      "Couldn't find spidernet firmware in filesystem " \
+                      "or host firmware\n");
+       return err;
+}
+
+/**
+ * spider_net_open - called upon ifonfig up
+ * @netdev: interface device structure
+ *
+ * returns 0 on success, <0 on failure
+ *
+ * spider_net_open allocates all the descriptors and memory needed for
+ * operation, sets up multicast list and enables interrupts
+ */
+int
+spider_net_open(struct net_device *netdev)
+{
+       struct spider_net_card *card = netdev_priv(netdev);
+       int result;
+
+       result = spider_net_init_firmware(card);
+       if (result)
+               goto init_firmware_failed;
+
+       /* start probing with copper */
+       card->aneg_count = 0;
+       card->medium = BCM54XX_COPPER;
+       spider_net_setup_aneg(card);
+       if (card->phy.def->phy_id)
+               mod_timer(&card->aneg_timer, jiffies + SPIDER_NET_ANEG_TIMER);
+
+       result = spider_net_init_chain(card, &card->tx_chain);
+       if (result)
+               goto alloc_tx_failed;
+       card->low_watermark = NULL;
+
+       result = spider_net_init_chain(card, &card->rx_chain);
+       if (result)
+               goto alloc_rx_failed;
+
+       /* Allocate rx skbs */
+       result = spider_net_alloc_rx_skbs(card);
+       if (result)
+               goto alloc_skbs_failed;
+
+       spider_net_set_multi(netdev);
+
+       /* further enhancement: setup hw vlan, if needed */
+
+       result = -EBUSY;
+       if (request_irq(netdev->irq, spider_net_interrupt,
+                            IRQF_SHARED, netdev->name, netdev))
+               goto register_int_failed;
+
+       spider_net_enable_card(card);
+
+       netif_start_queue(netdev);
+       netif_carrier_on(netdev);
+       napi_enable(&card->napi);
+
+       spider_net_enable_interrupts(card);
+
+       return 0;
+
+register_int_failed:
+       spider_net_free_rx_chain_contents(card);
+alloc_skbs_failed:
+       spider_net_free_chain(card, &card->rx_chain);
+alloc_rx_failed:
+       spider_net_free_chain(card, &card->tx_chain);
+alloc_tx_failed:
+       del_timer_sync(&card->aneg_timer);
+init_firmware_failed:
+       return result;
+}
+
+/**
+ * spider_net_link_phy
+ * @data: used for pointer to card structure
+ *
+ */
+static void spider_net_link_phy(unsigned long data)
+{
+       struct spider_net_card *card = (struct spider_net_card *)data;
+       struct mii_phy *phy = &card->phy;
+
+       /* if link didn't come up after SPIDER_NET_ANEG_TIMEOUT tries, setup phy again */
+       if (card->aneg_count > SPIDER_NET_ANEG_TIMEOUT) {
+
+               pr_debug("%s: link is down trying to bring it up\n",
+                        card->netdev->name);
+
+               switch (card->medium) {
+               case BCM54XX_COPPER:
+                       /* enable fiber with autonegotiation first */
+                       if (phy->def->ops->enable_fiber)
+                               phy->def->ops->enable_fiber(phy, 1);
+                       card->medium = BCM54XX_FIBER;
+                       break;
+
+               case BCM54XX_FIBER:
+                       /* fiber didn't come up, try to disable fiber autoneg */
+                       if (phy->def->ops->enable_fiber)
+                               phy->def->ops->enable_fiber(phy, 0);
+                       card->medium = BCM54XX_UNKNOWN;
+                       break;
+
+               case BCM54XX_UNKNOWN:
+                       /* copper, fiber with and without failed,
+                        * retry from beginning */
+                       spider_net_setup_aneg(card);
+                       card->medium = BCM54XX_COPPER;
+                       break;
+               }
+
+               card->aneg_count = 0;
+               mod_timer(&card->aneg_timer, jiffies + SPIDER_NET_ANEG_TIMER);
+               return;
+       }
+
+       /* link still not up, try again later */
+       if (!(phy->def->ops->poll_link(phy))) {
+               card->aneg_count++;
+               mod_timer(&card->aneg_timer, jiffies + SPIDER_NET_ANEG_TIMER);
+               return;
+       }
+
+       /* link came up, get abilities */
+       phy->def->ops->read_link(phy);
+
+       spider_net_write_reg(card, SPIDER_NET_GMACST,
+                            spider_net_read_reg(card, SPIDER_NET_GMACST));
+       spider_net_write_reg(card, SPIDER_NET_GMACINTEN, 0x4);
+
+       if (phy->speed == 1000)
+               spider_net_write_reg(card, SPIDER_NET_GMACMODE, 0x00000001);
+       else
+               spider_net_write_reg(card, SPIDER_NET_GMACMODE, 0);
+
+       card->aneg_count = 0;
+
+       pr_info("%s: link up, %i Mbps, %s-duplex %sautoneg.\n",
+               card->netdev->name, phy->speed,
+               phy->duplex == 1 ? "Full" : "Half",
+               phy->autoneg == 1 ? "" : "no ");
+}
+
+/**
+ * spider_net_setup_phy - setup PHY
+ * @card: card structure
+ *
+ * returns 0 on success, <0 on failure
+ *
+ * spider_net_setup_phy is used as part of spider_net_probe.
+ **/
+static int
+spider_net_setup_phy(struct spider_net_card *card)
+{
+       struct mii_phy *phy = &card->phy;
+
+       spider_net_write_reg(card, SPIDER_NET_GDTDMASEL,
+                            SPIDER_NET_DMASEL_VALUE);
+       spider_net_write_reg(card, SPIDER_NET_GPCCTRL,
+                            SPIDER_NET_PHY_CTRL_VALUE);
+
+       phy->dev = card->netdev;
+       phy->mdio_read = spider_net_read_phy;
+       phy->mdio_write = spider_net_write_phy;
+
+       for (phy->mii_id = 1; phy->mii_id <= 31; phy->mii_id++) {
+               unsigned short id;
+               id = spider_net_read_phy(card->netdev, phy->mii_id, MII_BMSR);
+               if (id != 0x0000 && id != 0xffff) {
+                       if (!sungem_phy_probe(phy, phy->mii_id)) {
+                               pr_info("Found %s.\n", phy->def->name);
+                               break;
+                       }
+               }
+       }
+
+       return 0;
+}
+
+/**
+ * spider_net_workaround_rxramfull - work around firmware bug
+ * @card: card structure
+ *
+ * no return value
+ **/
+static void
+spider_net_workaround_rxramfull(struct spider_net_card *card)
+{
+       int i, sequencer = 0;
+
+       /* cancel reset */
+       spider_net_write_reg(card, SPIDER_NET_CKRCTRL,
+                            SPIDER_NET_CKRCTRL_RUN_VALUE);
+
+       /* empty sequencer data */
+       for (sequencer = 0; sequencer < SPIDER_NET_FIRMWARE_SEQS;
+            sequencer++) {
+               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 +
+                                            sequencer * 8, 0x0);
+               }
+       }
+
+       /* set sequencer operation */
+       spider_net_write_reg(card, SPIDER_NET_GSINIT, 0x000000fe);
+
+       /* reset */
+       spider_net_write_reg(card, SPIDER_NET_CKRCTRL,
+                            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);
+
+       napi_disable(&card->napi);
+       netif_carrier_off(netdev);
+       netif_stop_queue(netdev);
+       del_timer_sync(&card->tx_timer);
+       del_timer_sync(&card->aneg_timer);
+
+       spider_net_disable_interrupts(card);
+
+       free_irq(netdev->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)
+ * @data: data, is interface device structure
+ *
+ * called as task when tx hangs, resets interface (if interface is up)
+ */
+static void
+spider_net_tx_timeout_task(struct work_struct *work)
+{
+       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;
+
+       netif_device_detach(netdev);
+       spider_net_stop(netdev);
+
+       spider_net_workaround_rxramfull(card);
+       spider_net_init_card(card);
+
+       if (spider_net_setup_phy(card))
+               goto out;
+
+       spider_net_open(netdev);
+       spider_net_kick_tx_dma(card);
+       netif_device_attach(netdev);
+
+out:
+       atomic_dec(&card->tx_timeout_task_counter);
+}
+
+/**
+ * spider_net_tx_timeout - called when the tx timeout watchdog kicks in.
+ * @netdev: interface device structure
+ *
+ * called, if tx hangs. Schedules a task that resets the interface
+ */
+static void
+spider_net_tx_timeout(struct net_device *netdev)
+{
+       struct spider_net_card *card;
+
+       card = netdev_priv(netdev);
+       atomic_inc(&card->tx_timeout_task_counter);
+       if (netdev->flags & IFF_UP)
+               schedule_work(&card->tx_timeout_task);
+       else
+               atomic_dec(&card->tx_timeout_task_counter);
+       card->spider_stats.tx_timeouts++;
+}
+
+static const struct net_device_ops spider_net_ops = {
+       .ndo_open               = spider_net_open,
+       .ndo_stop               = spider_net_stop,
+       .ndo_start_xmit         = spider_net_xmit,
+       .ndo_set_rx_mode        = spider_net_set_multi,
+       .ndo_set_mac_address    = spider_net_set_mac,
+       .ndo_change_mtu         = spider_net_change_mtu,
+       .ndo_do_ioctl           = spider_net_do_ioctl,
+       .ndo_tx_timeout         = spider_net_tx_timeout,
+       .ndo_validate_addr      = eth_validate_addr,
+       /* HW VLAN */
+#ifdef CONFIG_NET_POLL_CONTROLLER
+       /* poll controller */
+       .ndo_poll_controller    = spider_net_poll_controller,
+#endif /* CONFIG_NET_POLL_CONTROLLER */
+};
+
+/**
+ * spider_net_setup_netdev_ops - initialization of net_device operations
+ * @netdev: net_device structure
+ *
+ * fills out function pointers in the net_device structure
+ */
+static void
+spider_net_setup_netdev_ops(struct net_device *netdev)
+{
+       netdev->netdev_ops = &spider_net_ops;
+       netdev->watchdog_timeo = SPIDER_NET_WATCHDOG_TIMEOUT;
+       /* ethtool ops */
+       netdev->ethtool_ops = &spider_net_ethtool_ops;
+}
+
+/**
+ * spider_net_setup_netdev - initialization of net_device
+ * @card: card structure
+ *
+ * Returns 0 on success or <0 on failure
+ *
+ * spider_net_setup_netdev initializes the net_device structure
+ **/
+static int
+spider_net_setup_netdev(struct spider_net_card *card)
+{
+       int result;
+       struct net_device *netdev = card->netdev;
+       struct device_node *dn;
+       struct sockaddr addr;
+       const u8 *mac;
+
+       SET_NETDEV_DEV(netdev, &card->pdev->dev);
+
+       pci_set_drvdata(card->pdev, netdev);
+
+       init_timer(&card->tx_timer);
+       card->tx_timer.function =
+               (void (*)(unsigned long)) spider_net_cleanup_tx_ring;
+       card->tx_timer.data = (unsigned long) card;
+       netdev->irq = card->pdev->irq;
+
+       card->aneg_count = 0;
+       init_timer(&card->aneg_timer);
+       card->aneg_timer.function = spider_net_link_phy;
+       card->aneg_timer.data = (unsigned long) card;
+
+       netif_napi_add(netdev, &card->napi,
+                      spider_net_poll, SPIDER_NET_NAPI_WEIGHT);
+
+       spider_net_setup_netdev_ops(netdev);
+
+       netdev->hw_features = NETIF_F_RXCSUM | NETIF_F_IP_CSUM;
+       if (SPIDER_NET_RX_CSUM_DEFAULT)
+               netdev->features |= NETIF_F_RXCSUM;
+       netdev->features |= NETIF_F_IP_CSUM | NETIF_F_LLTX;
+       /* some time: NETIF_F_HW_VLAN_CTAG_TX | NETIF_F_HW_VLAN_CTAG_RX |
+        *              NETIF_F_HW_VLAN_CTAG_FILTER */
+
+       netdev->irq = card->pdev->irq;
+       card->num_rx_ints = 0;
+       card->ignore_rx_ramfull = 0;
+
+       dn = pci_device_to_OF_node(card->pdev);
+       if (!dn)
+               return -EIO;
+
+       mac = of_get_property(dn, "local-mac-address", NULL);
+       if (!mac)
+               return -EIO;
+       memcpy(addr.sa_data, mac, ETH_ALEN);
+
+       result = spider_net_set_mac(netdev, &addr);
+       if ((result) && (netif_msg_probe(card)))
+               dev_err(&card->netdev->dev,
+                       "Failed to set MAC address: %i\n", result);
+
+       result = register_netdev(netdev);
+       if (result) {
+               if (netif_msg_probe(card))
+                       dev_err(&card->netdev->dev,
+                               "Couldn't register net_device: %i\n", result);
+               return result;
+       }
+
+       if (netif_msg_probe(card))
+               pr_info("Initialized device %s.\n", netdev->name);
+
+       return 0;
+}
+
+/**
+ * spider_net_alloc_card - allocates net_device and card structure
+ *
+ * returns the card structure or NULL in case of errors
+ *
+ * the card and net_device structures are linked to each other
+ */
+static struct spider_net_card *
+spider_net_alloc_card(void)
+{
+       struct net_device *netdev;
+       struct spider_net_card *card;
+       size_t alloc_size;
+
+       alloc_size = sizeof(struct spider_net_card) +
+          (tx_descriptors + rx_descriptors) * sizeof(struct spider_net_descr);
+       netdev = alloc_etherdev(alloc_size);
+       if (!netdev)
+               return NULL;
+
+       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);
+       init_waitqueue_head(&card->waitq);
+       atomic_set(&card->tx_timeout_task_counter, 0);
+
+       card->rx_chain.num_desc = rx_descriptors;
+       card->rx_chain.ring = card->darray;
+       card->tx_chain.num_desc = tx_descriptors;
+       card->tx_chain.ring = card->darray + rx_descriptors;
+
+       return card;
+}
+
+/**
+ * spider_net_undo_pci_setup - releases PCI ressources
+ * @card: card structure
+ *
+ * spider_net_undo_pci_setup releases the mapped regions
+ */
+static void
+spider_net_undo_pci_setup(struct spider_net_card *card)
+{
+       iounmap(card->regs);
+       pci_release_regions(card->pdev);
+}
+
+/**
+ * spider_net_setup_pci_dev - sets up the device in terms of PCI operations
+ * @pdev: PCI device
+ *
+ * Returns the card structure or NULL if any errors occur
+ *
+ * spider_net_setup_pci_dev initializes pdev and together with the
+ * functions called in spider_net_open configures the device so that
+ * data can be transferred over it
+ * The net_device structure is attached to the card structure, if the
+ * function returns without error.
+ **/
+static struct spider_net_card *
+spider_net_setup_pci_dev(struct pci_dev *pdev)
+{
+       struct spider_net_card *card;
+       unsigned long mmio_start, mmio_len;
+
+       if (pci_enable_device(pdev)) {
+               dev_err(&pdev->dev, "Couldn't enable PCI device\n");
+               return NULL;
+       }
+
+       if (!(pci_resource_flags(pdev, 0) & IORESOURCE_MEM)) {
+               dev_err(&pdev->dev,
+                       "Couldn't find proper PCI device base address.\n");
+               goto out_disable_dev;
+       }
+
+       if (pci_request_regions(pdev, spider_net_driver_name)) {
+               dev_err(&pdev->dev,
+                       "Couldn't obtain PCI resources, aborting.\n");
+               goto out_disable_dev;
+       }
+
+       pci_set_master(pdev);
+
+       card = spider_net_alloc_card();
+       if (!card) {
+               dev_err(&pdev->dev,
+                       "Couldn't allocate net_device structure, aborting.\n");
+               goto out_release_regions;
+       }
+       card->pdev = pdev;
+
+       /* fetch base address and length of first resource */
+       mmio_start = pci_resource_start(pdev, 0);
+       mmio_len = pci_resource_len(pdev, 0);
+
+       card->netdev->mem_start = mmio_start;
+       card->netdev->mem_end = mmio_start + mmio_len;
+       card->regs = ioremap(mmio_start, mmio_len);
+
+       if (!card->regs) {
+               dev_err(&pdev->dev,
+                       "Couldn't obtain PCI resources, aborting.\n");
+               goto out_release_regions;
+       }
+
+       return card;
+
+out_release_regions:
+       pci_release_regions(pdev);
+out_disable_dev:
+       pci_disable_device(pdev);
+       return NULL;
+}
+
+/**
+ * spider_net_probe - initialization of a device
+ * @pdev: PCI device
+ * @ent: entry in the device id list
+ *
+ * Returns 0 on success, <0 on failure
+ *
+ * spider_net_probe initializes pdev and registers a net_device
+ * structure for it. After that, the device can be ifconfig'ed up
+ **/
+static int
+spider_net_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
+{
+       int err = -EIO;
+       struct spider_net_card *card;
+
+       card = spider_net_setup_pci_dev(pdev);
+       if (!card)
+               goto out;
+
+       spider_net_workaround_rxramfull(card);
+       spider_net_init_card(card);
+
+       err = spider_net_setup_phy(card);
+       if (err)
+               goto out_undo_pci;
+
+       err = spider_net_setup_netdev(card);
+       if (err)
+               goto out_undo_pci;
+
+       return 0;
+
+out_undo_pci:
+       spider_net_undo_pci_setup(card);
+       free_netdev(card->netdev);
+out:
+       return err;
+}
+
+/**
+ * spider_net_remove - removal of a device
+ * @pdev: PCI device
+ *
+ * Returns 0 on success, <0 on failure
+ *
+ * spider_net_remove is called to remove the device and unregisters the
+ * net_device
+ **/
+static void
+spider_net_remove(struct pci_dev *pdev)
+{
+       struct net_device *netdev;
+       struct spider_net_card *card;
+
+       netdev = pci_get_drvdata(pdev);
+       card = netdev_priv(netdev);
+
+       wait_event(card->waitq,
+                  atomic_read(&card->tx_timeout_task_counter) == 0);
+
+       unregister_netdev(netdev);
+
+       /* switch off card */
+       spider_net_write_reg(card, SPIDER_NET_CKRCTRL,
+                            SPIDER_NET_CKRCTRL_STOP_VALUE);
+       spider_net_write_reg(card, SPIDER_NET_CKRCTRL,
+                            SPIDER_NET_CKRCTRL_RUN_VALUE);
+
+       spider_net_undo_pci_setup(card);
+       free_netdev(netdev);
+}
+
+static struct pci_driver spider_net_driver = {
+       .name           = spider_net_driver_name,
+       .id_table       = spider_net_pci_tbl,
+       .probe          = spider_net_probe,
+       .remove         = spider_net_remove
+};
+
+/**
+ * spider_net_init - init function when the driver is loaded
+ *
+ * spider_net_init registers the device 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);
+       }
+       if (rx_descriptors > SPIDER_NET_RX_DESCRIPTORS_MAX) {
+               rx_descriptors = SPIDER_NET_RX_DESCRIPTORS_MAX;
+               pr_info("adjusting rx descriptors to %i.\n", rx_descriptors);
+       }
+       if (tx_descriptors < SPIDER_NET_TX_DESCRIPTORS_MIN) {
+               tx_descriptors = SPIDER_NET_TX_DESCRIPTORS_MIN;
+               pr_info("adjusting tx descriptors to %i.\n", tx_descriptors);
+       }
+       if (tx_descriptors > SPIDER_NET_TX_DESCRIPTORS_MAX) {
+               tx_descriptors = SPIDER_NET_TX_DESCRIPTORS_MAX;
+               pr_info("adjusting tx descriptors to %i.\n", tx_descriptors);
+       }
+
+       return pci_register_driver(&spider_net_driver);
+}
+
+/**
+ * spider_net_cleanup - exit function when driver is unloaded
+ *
+ * spider_net_cleanup unregisters the device driver
+ */
+static void __exit spider_net_cleanup(void)
+{
+       pci_unregister_driver(&spider_net_driver);
+}
+
+module_init(spider_net_init);
+module_exit(spider_net_cleanup);