Linux 3.3-rc6

[linux/fpc-iii.git] / drivers / staging / octeon / ethernet-tx.c

/*********************************************************************
 * Author: Cavium Networks
 *
 * Contact: support@caviumnetworks.com
 * This file is part of the OCTEON SDK
 *
 * Copyright (c) 2003-2010 Cavium Networks
 *
 * This file is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, Version 2, as
 * published by the Free Software Foundation.
 *
 * This file is distributed in the hope that it will be useful, but
 * AS-IS and WITHOUT ANY WARRANTY; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE, TITLE, or
 * NONINFRINGEMENT.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this file; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 * or visit http://www.gnu.org/licenses/.
 *
 * This file may also be available under a different license from Cavium.
 * Contact Cavium Networks for more information
*********************************************************************/
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/netdevice.h>
#include <linux/init.h>
#include <linux/etherdevice.h>
#include <linux/ip.h>
#include <linux/ratelimit.h>
#include <linux/string.h>
#include <net/dst.h>
#ifdef CONFIG_XFRM
#include <linux/xfrm.h>
#include <net/xfrm.h>
#endif /* CONFIG_XFRM */

#include <linux/atomic.h>

#include <asm/octeon/octeon.h>

#include "ethernet-defines.h"
#include "octeon-ethernet.h"
#include "ethernet-tx.h"
#include "ethernet-util.h"

#include <asm/octeon/cvmx-wqe.h>
#include <asm/octeon/cvmx-fau.h>
#include <asm/octeon/cvmx-pip.h>
#include <asm/octeon/cvmx-pko.h>
#include <asm/octeon/cvmx-helper.h>

#include <asm/octeon/cvmx-gmxx-defs.h>

#define CVM_OCT_SKB_CB(skb)     ((u64 *)((skb)->cb))

/*
 * You can define GET_SKBUFF_QOS() to override how the skbuff output
 * function determines which output queue is used. The default
 * implementation always uses the base queue for the port. If, for
 * example, you wanted to use the skb->priority fieid, define
 * GET_SKBUFF_QOS as: #define GET_SKBUFF_QOS(skb) ((skb)->priority)
 */
#ifndef GET_SKBUFF_QOS
#define GET_SKBUFF_QOS(skb) 0
#endif

static void cvm_oct_tx_do_cleanup(unsigned long arg);
static DECLARE_TASKLET(cvm_oct_tx_cleanup_tasklet, cvm_oct_tx_do_cleanup, 0);

/* Maximum number of SKBs to try to free per xmit packet. */
#define MAX_SKB_TO_FREE (MAX_OUT_QUEUE_DEPTH * 2)

static inline int32_t cvm_oct_adjust_skb_to_free(int32_t skb_to_free, int fau)
{
        int32_t undo;
        undo = skb_to_free > 0 ? MAX_SKB_TO_FREE : skb_to_free + MAX_SKB_TO_FREE;
        if (undo > 0)
                cvmx_fau_atomic_add32(fau, -undo);
        skb_to_free = -skb_to_free > MAX_SKB_TO_FREE ? MAX_SKB_TO_FREE : -skb_to_free;
        return skb_to_free;
}

static void cvm_oct_kick_tx_poll_watchdog(void)
{
        union cvmx_ciu_timx ciu_timx;
        ciu_timx.u64 = 0;
        ciu_timx.s.one_shot = 1;
        ciu_timx.s.len = cvm_oct_tx_poll_interval;
        cvmx_write_csr(CVMX_CIU_TIMX(1), ciu_timx.u64);
}

void cvm_oct_free_tx_skbs(struct net_device *dev)
{
        int32_t skb_to_free;
        int qos, queues_per_port;
        int total_freed = 0;
        int total_remaining = 0;
        unsigned long flags;
        struct octeon_ethernet *priv = netdev_priv(dev);

        queues_per_port = cvmx_pko_get_num_queues(priv->port);
        /* Drain any pending packets in the free list */
        for (qos = 0; qos < queues_per_port; qos++) {
                if (skb_queue_len(&priv->tx_free_list[qos]) == 0)
                        continue;
                skb_to_free = cvmx_fau_fetch_and_add32(priv->fau+qos*4, MAX_SKB_TO_FREE);
                skb_to_free = cvm_oct_adjust_skb_to_free(skb_to_free, priv->fau+qos*4);


                total_freed += skb_to_free;
                if (skb_to_free > 0) {
                        struct sk_buff *to_free_list = NULL;
                        spin_lock_irqsave(&priv->tx_free_list[qos].lock, flags);
                        while (skb_to_free > 0) {
                                struct sk_buff *t = __skb_dequeue(&priv->tx_free_list[qos]);
                                t->next = to_free_list;
                                to_free_list = t;
                                skb_to_free--;
                        }
                        spin_unlock_irqrestore(&priv->tx_free_list[qos].lock, flags);
                        /* Do the actual freeing outside of the lock. */
                        while (to_free_list) {
                                struct sk_buff *t = to_free_list;
                                to_free_list = to_free_list->next;
                                dev_kfree_skb_any(t);
                        }
                }
                total_remaining += skb_queue_len(&priv->tx_free_list[qos]);
        }
        if (total_freed >= 0 && netif_queue_stopped(dev))
                netif_wake_queue(dev);
        if (total_remaining)
                cvm_oct_kick_tx_poll_watchdog();
}

/**
 * cvm_oct_xmit - transmit a packet
 * @skb:    Packet to send
 * @dev:    Device info structure
 *
 * Returns Always returns NETDEV_TX_OK
 */
int cvm_oct_xmit(struct sk_buff *skb, struct net_device *dev)
{
        cvmx_pko_command_word0_t pko_command;
        union cvmx_buf_ptr hw_buffer;
        uint64_t old_scratch;
        uint64_t old_scratch2;
        int qos;
        int i;
        enum {QUEUE_CORE, QUEUE_HW, QUEUE_DROP} queue_type;
        struct octeon_ethernet *priv = netdev_priv(dev);
        struct sk_buff *to_free_list;
        int32_t skb_to_free;
        int32_t buffers_to_free;
        u32 total_to_clean;
        unsigned long flags;
#if REUSE_SKBUFFS_WITHOUT_FREE
        unsigned char *fpa_head;
#endif

        /*
         * Prefetch the private data structure.  It is larger that one
         * cache line.
         */
        prefetch(priv);

        /*
         * The check on CVMX_PKO_QUEUES_PER_PORT_* is designed to
         * completely remove "qos" in the event neither interface
         * supports multiple queues per port.
         */
        if ((CVMX_PKO_QUEUES_PER_PORT_INTERFACE0 > 1) ||
            (CVMX_PKO_QUEUES_PER_PORT_INTERFACE1 > 1)) {
                qos = GET_SKBUFF_QOS(skb);
                if (qos <= 0)
                        qos = 0;
                else if (qos >= cvmx_pko_get_num_queues(priv->port))
                        qos = 0;
        } else
                qos = 0;

        if (USE_ASYNC_IOBDMA) {
                /* Save scratch in case userspace is using it */
                CVMX_SYNCIOBDMA;
                old_scratch = cvmx_scratch_read64(CVMX_SCR_SCRATCH);
                old_scratch2 = cvmx_scratch_read64(CVMX_SCR_SCRATCH + 8);

                /*
                 * Fetch and increment the number of packets to be
                 * freed.
                 */
                cvmx_fau_async_fetch_and_add32(CVMX_SCR_SCRATCH + 8,
                                               FAU_NUM_PACKET_BUFFERS_TO_FREE,
                                               0);
                cvmx_fau_async_fetch_and_add32(CVMX_SCR_SCRATCH,
                                               priv->fau + qos * 4,
                                               MAX_SKB_TO_FREE);
        }

        /*
         * We have space for 6 segment pointers, If there will be more
         * than that, we must linearize.
         */
        if (unlikely(skb_shinfo(skb)->nr_frags > 5)) {
                if (unlikely(__skb_linearize(skb))) {
                        queue_type = QUEUE_DROP;
                        if (USE_ASYNC_IOBDMA) {
                                /* Get the number of skbuffs in use by the hardware */
                                CVMX_SYNCIOBDMA;
                                skb_to_free = cvmx_scratch_read64(CVMX_SCR_SCRATCH);
                        } else {
                                /* Get the number of skbuffs in use by the hardware */
                                skb_to_free = cvmx_fau_fetch_and_add32(priv->fau + qos * 4,
                                                                       MAX_SKB_TO_FREE);
                        }
                        skb_to_free = cvm_oct_adjust_skb_to_free(skb_to_free, priv->fau + qos * 4);
                        spin_lock_irqsave(&priv->tx_free_list[qos].lock, flags);
                        goto skip_xmit;
                }
        }

        /*
         * The CN3XXX series of parts has an errata (GMX-401) which
         * causes the GMX block to hang if a collision occurs towards
         * the end of a <68 byte packet. As a workaround for this, we
         * pad packets to be 68 bytes whenever we are in half duplex
         * mode. We don't handle the case of having a small packet but
         * no room to add the padding.  The kernel should always give
         * us at least a cache line
         */
        if ((skb->len < 64) && OCTEON_IS_MODEL(OCTEON_CN3XXX)) {
                union cvmx_gmxx_prtx_cfg gmx_prt_cfg;
                int interface = INTERFACE(priv->port);
                int index = INDEX(priv->port);

                if (interface < 2) {
                        /* We only need to pad packet in half duplex mode */
                        gmx_prt_cfg.u64 =
                            cvmx_read_csr(CVMX_GMXX_PRTX_CFG(index, interface));
                        if (gmx_prt_cfg.s.duplex == 0) {
                                int add_bytes = 64 - skb->len;
                                if ((skb_tail_pointer(skb) + add_bytes) <=
                                    skb_end_pointer(skb))
                                        memset(__skb_put(skb, add_bytes), 0,
                                               add_bytes);
                        }
                }
        }

        /* Build the PKO command */
        pko_command.u64 = 0;
        pko_command.s.n2 = 1;   /* Don't pollute L2 with the outgoing packet */
        pko_command.s.segs = 1;
        pko_command.s.total_bytes = skb->len;
        pko_command.s.size0 = CVMX_FAU_OP_SIZE_32;
        pko_command.s.subone0 = 1;

        pko_command.s.dontfree = 1;

        /* Build the PKO buffer pointer */
        hw_buffer.u64 = 0;
        if (skb_shinfo(skb)->nr_frags == 0) {
                hw_buffer.s.addr = XKPHYS_TO_PHYS((u64)skb->data);
                hw_buffer.s.pool = 0;
                hw_buffer.s.size = skb->len;
        } else {
                hw_buffer.s.addr = XKPHYS_TO_PHYS((u64)skb->data);
                hw_buffer.s.pool = 0;
                hw_buffer.s.size = skb_headlen(skb);
                CVM_OCT_SKB_CB(skb)[0] = hw_buffer.u64;
                for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {
                        struct skb_frag_struct *fs = skb_shinfo(skb)->frags + i;
                        hw_buffer.s.addr = XKPHYS_TO_PHYS((u64)(page_address(fs->page.p) + fs->page_offset));
                        hw_buffer.s.size = fs->size;
                        CVM_OCT_SKB_CB(skb)[i + 1] = hw_buffer.u64;
                }
                hw_buffer.s.addr = XKPHYS_TO_PHYS((u64)CVM_OCT_SKB_CB(skb));
                hw_buffer.s.size = skb_shinfo(skb)->nr_frags + 1;
                pko_command.s.segs = skb_shinfo(skb)->nr_frags + 1;
                pko_command.s.gather = 1;
                goto dont_put_skbuff_in_hw;
        }

        /*
         * See if we can put this skb in the FPA pool. Any strange
         * behavior from the Linux networking stack will most likely
         * be caused by a bug in the following code. If some field is
         * in use by the network stack and get carried over when a
         * buffer is reused, bad thing may happen.  If in doubt and
         * you dont need the absolute best performance, disable the
         * define REUSE_SKBUFFS_WITHOUT_FREE. The reuse of buffers has
         * shown a 25% increase in performance under some loads.
         */
#if REUSE_SKBUFFS_WITHOUT_FREE
        fpa_head = skb->head + 256 - ((unsigned long)skb->head & 0x7f);
        if (unlikely(skb->data < fpa_head)) {
                /*
                 * printk("TX buffer beginning can't meet FPA
                 * alignment constraints\n");
                 */
                goto dont_put_skbuff_in_hw;
        }
        if (unlikely
            ((skb_end_pointer(skb) - fpa_head) < CVMX_FPA_PACKET_POOL_SIZE)) {
                /*
                   printk("TX buffer isn't large enough for the FPA\n");
                 */
                goto dont_put_skbuff_in_hw;
        }
        if (unlikely(skb_shared(skb))) {
                /*
                   printk("TX buffer sharing data with someone else\n");
                 */
                goto dont_put_skbuff_in_hw;
        }
        if (unlikely(skb_cloned(skb))) {
                /*
                   printk("TX buffer has been cloned\n");
                 */
                goto dont_put_skbuff_in_hw;
        }
        if (unlikely(skb_header_cloned(skb))) {
                /*
                   printk("TX buffer header has been cloned\n");
                 */
                goto dont_put_skbuff_in_hw;
        }
        if (unlikely(skb->destructor)) {
                /*
                   printk("TX buffer has a destructor\n");
                 */
                goto dont_put_skbuff_in_hw;
        }
        if (unlikely(skb_shinfo(skb)->nr_frags)) {
                /*
                   printk("TX buffer has fragments\n");
                 */
                goto dont_put_skbuff_in_hw;
        }
        if (unlikely
            (skb->truesize !=
             sizeof(*skb) + skb_end_pointer(skb) - skb->head)) {
                /*
                   printk("TX buffer truesize has been changed\n");
                 */
                goto dont_put_skbuff_in_hw;
        }

        /*
         * We can use this buffer in the FPA.  We don't need the FAU
         * update anymore
         */
        pko_command.s.dontfree = 0;

        hw_buffer.s.back = ((unsigned long)skb->data >> 7) - ((unsigned long)fpa_head >> 7);
        *(struct sk_buff **)(fpa_head - sizeof(void *)) = skb;

        /*
         * The skbuff will be reused without ever being freed. We must
         * cleanup a bunch of core things.
         */
        dst_release(skb_dst(skb));
        skb_dst_set(skb, NULL);
#ifdef CONFIG_XFRM
        secpath_put(skb->sp);
        skb->sp = NULL;
#endif
        nf_reset(skb);

#ifdef CONFIG_NET_SCHED
        skb->tc_index = 0;
#ifdef CONFIG_NET_CLS_ACT
        skb->tc_verd = 0;
#endif /* CONFIG_NET_CLS_ACT */
#endif /* CONFIG_NET_SCHED */
#endif /* REUSE_SKBUFFS_WITHOUT_FREE */

dont_put_skbuff_in_hw:

        /* Check if we can use the hardware checksumming */
        if (USE_HW_TCPUDP_CHECKSUM && (skb->protocol == htons(ETH_P_IP)) &&
            (ip_hdr(skb)->version == 4) && (ip_hdr(skb)->ihl == 5) &&
            ((ip_hdr(skb)->frag_off == 0) || (ip_hdr(skb)->frag_off == 1 << 14))
            && ((ip_hdr(skb)->protocol == IPPROTO_TCP)
                || (ip_hdr(skb)->protocol == IPPROTO_UDP))) {
                /* Use hardware checksum calc */
                pko_command.s.ipoffp1 = sizeof(struct ethhdr) + 1;
        }

        if (USE_ASYNC_IOBDMA) {
                /* Get the number of skbuffs in use by the hardware */
                CVMX_SYNCIOBDMA;
                skb_to_free = cvmx_scratch_read64(CVMX_SCR_SCRATCH);
                buffers_to_free = cvmx_scratch_read64(CVMX_SCR_SCRATCH + 8);
        } else {
                /* Get the number of skbuffs in use by the hardware */
                skb_to_free = cvmx_fau_fetch_and_add32(priv->fau + qos * 4,
                                                       MAX_SKB_TO_FREE);
                buffers_to_free =
                    cvmx_fau_fetch_and_add32(FAU_NUM_PACKET_BUFFERS_TO_FREE, 0);
        }

        skb_to_free = cvm_oct_adjust_skb_to_free(skb_to_free, priv->fau+qos*4);

        /*
         * If we're sending faster than the receive can free them then
         * don't do the HW free.
         */
        if ((buffers_to_free < -100) && !pko_command.s.dontfree)
                pko_command.s.dontfree = 1;

        if (pko_command.s.dontfree) {
                queue_type = QUEUE_CORE;
                pko_command.s.reg0 = priv->fau+qos*4;
        } else {
                queue_type = QUEUE_HW;
        }
        if (USE_ASYNC_IOBDMA)
                cvmx_fau_async_fetch_and_add32(CVMX_SCR_SCRATCH, FAU_TOTAL_TX_TO_CLEAN, 1);

        spin_lock_irqsave(&priv->tx_free_list[qos].lock, flags);

        /* Drop this packet if we have too many already queued to the HW */
        if (unlikely(skb_queue_len(&priv->tx_free_list[qos]) >= MAX_OUT_QUEUE_DEPTH)) {
                if (dev->tx_queue_len != 0) {
                        /* Drop the lock when notifying the core.  */
                        spin_unlock_irqrestore(&priv->tx_free_list[qos].lock, flags);
                        netif_stop_queue(dev);
                        spin_lock_irqsave(&priv->tx_free_list[qos].lock, flags);
                } else {
                        /* If not using normal queueing.  */
                        queue_type = QUEUE_DROP;
                        goto skip_xmit;
                }
        }

        cvmx_pko_send_packet_prepare(priv->port, priv->queue + qos,
                                     CVMX_PKO_LOCK_NONE);

        /* Send the packet to the output queue */
        if (unlikely(cvmx_pko_send_packet_finish(priv->port,
                                                 priv->queue + qos,
                                                 pko_command, hw_buffer,
                                                 CVMX_PKO_LOCK_NONE))) {
                printk_ratelimited("%s: Failed to send the packet\n", dev->name);
                queue_type = QUEUE_DROP;
        }
skip_xmit:
        to_free_list = NULL;

        switch (queue_type) {
        case QUEUE_DROP:
                skb->next = to_free_list;
                to_free_list = skb;
                priv->stats.tx_dropped++;
                break;
        case QUEUE_HW:
                cvmx_fau_atomic_add32(FAU_NUM_PACKET_BUFFERS_TO_FREE, -1);
                break;
        case QUEUE_CORE:
                __skb_queue_tail(&priv->tx_free_list[qos], skb);
                break;
        default:
                BUG();
        }

        while (skb_to_free > 0) {
                struct sk_buff *t = __skb_dequeue(&priv->tx_free_list[qos]);
                t->next = to_free_list;
                to_free_list = t;
                skb_to_free--;
        }

        spin_unlock_irqrestore(&priv->tx_free_list[qos].lock, flags);

        /* Do the actual freeing outside of the lock. */
        while (to_free_list) {
                struct sk_buff *t = to_free_list;
                to_free_list = to_free_list->next;
                dev_kfree_skb_any(t);
        }

        if (USE_ASYNC_IOBDMA) {
                CVMX_SYNCIOBDMA;
                total_to_clean = cvmx_scratch_read64(CVMX_SCR_SCRATCH);
                /* Restore the scratch area */
                cvmx_scratch_write64(CVMX_SCR_SCRATCH, old_scratch);
                cvmx_scratch_write64(CVMX_SCR_SCRATCH + 8, old_scratch2);
        } else {
                total_to_clean = cvmx_fau_fetch_and_add32(FAU_TOTAL_TX_TO_CLEAN, 1);
        }

        if (total_to_clean & 0x3ff) {
                /*
                 * Schedule the cleanup tasklet every 1024 packets for
                 * the pathological case of high traffic on one port
                 * delaying clean up of packets on a different port
                 * that is blocked waiting for the cleanup.
                 */
                tasklet_schedule(&cvm_oct_tx_cleanup_tasklet);
        }

        cvm_oct_kick_tx_poll_watchdog();

        return NETDEV_TX_OK;
}

/**
 * cvm_oct_xmit_pow - transmit a packet to the POW
 * @skb:    Packet to send
 * @dev:    Device info structure

 * Returns Always returns zero
 */
int cvm_oct_xmit_pow(struct sk_buff *skb, struct net_device *dev)
{
        struct octeon_ethernet *priv = netdev_priv(dev);
        void *packet_buffer;
        void *copy_location;

        /* Get a work queue entry */
        cvmx_wqe_t *work = cvmx_fpa_alloc(CVMX_FPA_WQE_POOL);
        if (unlikely(work == NULL)) {
                printk_ratelimited("%s: Failed to allocate a work "
                                   "queue entry\n", dev->name);
                priv->stats.tx_dropped++;
                dev_kfree_skb(skb);
                return 0;
        }

        /* Get a packet buffer */
        packet_buffer = cvmx_fpa_alloc(CVMX_FPA_PACKET_POOL);
        if (unlikely(packet_buffer == NULL)) {
                printk_ratelimited("%s: Failed to allocate a packet buffer\n",
                                   dev->name);
                cvmx_fpa_free(work, CVMX_FPA_WQE_POOL, DONT_WRITEBACK(1));
                priv->stats.tx_dropped++;
                dev_kfree_skb(skb);
                return 0;
        }

        /*
         * Calculate where we need to copy the data to. We need to
         * leave 8 bytes for a next pointer (unused). We also need to
         * include any configure skip. Then we need to align the IP
         * packet src and dest into the same 64bit word. The below
         * calculation may add a little extra, but that doesn't
         * hurt.
         */
        copy_location = packet_buffer + sizeof(uint64_t);
        copy_location += ((CVMX_HELPER_FIRST_MBUFF_SKIP + 7) & 0xfff8) + 6;

        /*
         * We have to copy the packet since whoever processes this
         * packet will free it to a hardware pool. We can't use the
         * trick of counting outstanding packets like in
         * cvm_oct_xmit.
         */
        memcpy(copy_location, skb->data, skb->len);

        /*
         * Fill in some of the work queue fields. We may need to add
         * more if the software at the other end needs them.
         */
        work->hw_chksum = skb->csum;
        work->len = skb->len;
        work->ipprt = priv->port;
        work->qos = priv->port & 0x7;
        work->grp = pow_send_group;
        work->tag_type = CVMX_HELPER_INPUT_TAG_TYPE;
        work->tag = pow_send_group;     /* FIXME */
        /* Default to zero. Sets of zero later are commented out */
        work->word2.u64 = 0;
        work->word2.s.bufs = 1;
        work->packet_ptr.u64 = 0;
        work->packet_ptr.s.addr = cvmx_ptr_to_phys(copy_location);
        work->packet_ptr.s.pool = CVMX_FPA_PACKET_POOL;
        work->packet_ptr.s.size = CVMX_FPA_PACKET_POOL_SIZE;
        work->packet_ptr.s.back = (copy_location - packet_buffer) >> 7;

        if (skb->protocol == htons(ETH_P_IP)) {
                work->word2.s.ip_offset = 14;
#if 0
                work->word2.s.vlan_valid = 0;   /* FIXME */
                work->word2.s.vlan_cfi = 0;     /* FIXME */
                work->word2.s.vlan_id = 0;      /* FIXME */
                work->word2.s.dec_ipcomp = 0;   /* FIXME */
#endif
                work->word2.s.tcp_or_udp =
                    (ip_hdr(skb)->protocol == IPPROTO_TCP)
                    || (ip_hdr(skb)->protocol == IPPROTO_UDP);
#if 0
                /* FIXME */
                work->word2.s.dec_ipsec = 0;
                /* We only support IPv4 right now */
                work->word2.s.is_v6 = 0;
                /* Hardware would set to zero */
                work->word2.s.software = 0;
                /* No error, packet is internal */
                work->word2.s.L4_error = 0;
#endif
                work->word2.s.is_frag = !((ip_hdr(skb)->frag_off == 0)
                                          || (ip_hdr(skb)->frag_off ==
                                              1 << 14));
#if 0
                /* Assume Linux is sending a good packet */
                work->word2.s.IP_exc = 0;
#endif
                work->word2.s.is_bcast = (skb->pkt_type == PACKET_BROADCAST);
                work->word2.s.is_mcast = (skb->pkt_type == PACKET_MULTICAST);
#if 0
                /* This is an IP packet */
                work->word2.s.not_IP = 0;
                /* No error, packet is internal */
                work->word2.s.rcv_error = 0;
                /* No error, packet is internal */
                work->word2.s.err_code = 0;
#endif

                /*
                 * When copying the data, include 4 bytes of the
                 * ethernet header to align the same way hardware
                 * does.
                 */
                memcpy(work->packet_data, skb->data + 10,
                       sizeof(work->packet_data));
        } else {
#if 0
                work->word2.snoip.vlan_valid = 0;       /* FIXME */
                work->word2.snoip.vlan_cfi = 0; /* FIXME */
                work->word2.snoip.vlan_id = 0;  /* FIXME */
                work->word2.snoip.software = 0; /* Hardware would set to zero */
#endif
                work->word2.snoip.is_rarp = skb->protocol == htons(ETH_P_RARP);
                work->word2.snoip.is_arp = skb->protocol == htons(ETH_P_ARP);
                work->word2.snoip.is_bcast =
                    (skb->pkt_type == PACKET_BROADCAST);
                work->word2.snoip.is_mcast =
                    (skb->pkt_type == PACKET_MULTICAST);
                work->word2.snoip.not_IP = 1;   /* IP was done up above */
#if 0
                /* No error, packet is internal */
                work->word2.snoip.rcv_error = 0;
                /* No error, packet is internal */
                work->word2.snoip.err_code = 0;
#endif
                memcpy(work->packet_data, skb->data, sizeof(work->packet_data));
        }

        /* Submit the packet to the POW */
        cvmx_pow_work_submit(work, work->tag, work->tag_type, work->qos,
                             work->grp);
        priv->stats.tx_packets++;
        priv->stats.tx_bytes += skb->len;
        dev_kfree_skb(skb);
        return 0;
}

/**
 * cvm_oct_tx_shutdown_dev - free all skb that are currently queued for TX.
 * @dev:    Device being shutdown
 *
 */
void cvm_oct_tx_shutdown_dev(struct net_device *dev)
{
        struct octeon_ethernet *priv = netdev_priv(dev);
        unsigned long flags;
        int qos;

        for (qos = 0; qos < 16; qos++) {
                spin_lock_irqsave(&priv->tx_free_list[qos].lock, flags);
                while (skb_queue_len(&priv->tx_free_list[qos]))
                        dev_kfree_skb_any(__skb_dequeue
                                          (&priv->tx_free_list[qos]));
                spin_unlock_irqrestore(&priv->tx_free_list[qos].lock, flags);
        }
}

static void cvm_oct_tx_do_cleanup(unsigned long arg)
{
        int port;

        for (port = 0; port < TOTAL_NUMBER_OF_PORTS; port++) {
                if (cvm_oct_device[port]) {
                        struct net_device *dev = cvm_oct_device[port];
                        cvm_oct_free_tx_skbs(dev);
                }
        }
}

static irqreturn_t cvm_oct_tx_cleanup_watchdog(int cpl, void *dev_id)
{
        /* Disable the interrupt.  */
        cvmx_write_csr(CVMX_CIU_TIMX(1), 0);
        /* Do the work in the tasklet.  */
        tasklet_schedule(&cvm_oct_tx_cleanup_tasklet);
        return IRQ_HANDLED;
}

void cvm_oct_tx_initialize(void)
{
        int i;

        /* Disable the interrupt.  */
        cvmx_write_csr(CVMX_CIU_TIMX(1), 0);
        /* Register an IRQ hander for to receive CIU_TIMX(1) interrupts */
        i = request_irq(OCTEON_IRQ_TIMER1,
                        cvm_oct_tx_cleanup_watchdog, 0,
                        "Ethernet", cvm_oct_device);

        if (i)
                panic("Could not acquire Ethernet IRQ %d\n", OCTEON_IRQ_TIMER1);
}

void cvm_oct_tx_shutdown(void)
{
        /* Free the interrupt handler */
        free_irq(OCTEON_IRQ_TIMER1, cvm_oct_device);
}