static int greth_poll(struct napi_struct *napi, int budget)
{
struct greth_private *greth;
int work_done = 0;
greth = container_of(napi, struct greth_private, napi);
if (greth->gbit_mac) {
greth_clean_tx_gbit(greth->netdev);
} else {
greth_clean_tx(greth->netdev);
}
restart_poll:
if (greth->gbit_mac) {
work_done += greth_rx_gbit(greth->netdev, budget - work_done);
} else {
work_done += greth_rx(greth->netdev, budget - work_done);
}
if (work_done < budget) {
napi_complete(napi);
if (greth_pending_packets(greth)) {
napi_reschedule(napi);
goto restart_poll;
}
}
greth_enable_irqs(greth);
return work_done;
}
static int greth_poll(struct napi_struct *napi, int budget)
{
struct greth_private *greth;
int work_done = 0;
unsigned long flags;
u32 mask, ctrl;
greth = container_of(napi, struct greth_private, napi);
restart_txrx_poll:
if (netif_queue_stopped(greth->netdev)) {
if (greth->gbit_mac)
greth_clean_tx_gbit(greth->netdev);
else
greth_clean_tx(greth->netdev);
}
if (greth->gbit_mac) {
work_done += greth_rx_gbit(greth->netdev, budget - work_done);
} else {
work_done += greth_rx(greth->netdev, budget - work_done);
}
if (work_done < budget) {
spin_lock_irqsave(&greth->devlock, flags);
ctrl = GRETH_REGLOAD(greth->regs->control);
if (netif_queue_stopped(greth->netdev)) {
GRETH_REGSAVE(greth->regs->control,
ctrl | GRETH_TXI | GRETH_RXI);
mask = GRETH_INT_RX | GRETH_INT_RE |
GRETH_INT_TX | GRETH_INT_TE;
} else {
GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_RXI);
mask = GRETH_INT_RX | GRETH_INT_RE;
}
if (GRETH_REGLOAD(greth->regs->status) & mask) {
GRETH_REGSAVE(greth->regs->control, ctrl);
spin_unlock_irqrestore(&greth->devlock, flags);
goto restart_txrx_poll;
} else {
__napi_complete(napi);
spin_unlock_irqrestore(&greth->devlock, flags);
}
}
return work_done;
}
static netdev_tx_t
greth_start_xmit_gbit(struct sk_buff *skb, struct net_device *dev)
{
struct greth_private *greth = netdev_priv(dev);
struct greth_bd *bdp;
u32 status = 0, dma_addr, ctrl;
int curr_tx, nr_frags, i, err = NETDEV_TX_OK;
unsigned long flags;
nr_frags = skb_shinfo(skb)->nr_frags;
/* Clean TX Ring */
greth_clean_tx_gbit(dev);
if (greth->tx_free < nr_frags + 1) {
spin_lock_irqsave(&greth->devlock, flags);/*save from poll/irq*/
ctrl = GRETH_REGLOAD(greth->regs->control);
/* Enable TX IRQ only if not already in poll() routine */
if (ctrl & GRETH_RXI)
GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_TXI);
netif_stop_queue(dev);
spin_unlock_irqrestore(&greth->devlock, flags);
err = NETDEV_TX_BUSY;
goto out;
}
if (netif_msg_pktdata(greth))
greth_print_tx_packet(skb);
if (unlikely(skb->len > MAX_FRAME_SIZE)) {
dev->stats.tx_errors++;
goto out;
}
/* Save skb pointer. */
greth->tx_skbuff[greth->tx_next] = skb;
/* Linear buf */
if (nr_frags != 0)
status = GRETH_TXBD_MORE;
if (skb->ip_summed == CHECKSUM_PARTIAL)
status |= GRETH_TXBD_CSALL;
status |= skb_headlen(skb) & GRETH_BD_LEN;
if (greth->tx_next == GRETH_TXBD_NUM_MASK)
status |= GRETH_BD_WR;
bdp = greth->tx_bd_base + greth->tx_next;
greth_write_bd(&bdp->stat, status);
dma_addr = dma_map_single(greth->dev, skb->data, skb_headlen(skb), DMA_TO_DEVICE);
if (unlikely(dma_mapping_error(greth->dev, dma_addr)))
goto map_error;
greth_write_bd(&bdp->addr, dma_addr);
curr_tx = NEXT_TX(greth->tx_next);
/* Frags */
for (i = 0; i < nr_frags; i++) {
skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
greth->tx_skbuff[curr_tx] = NULL;
bdp = greth->tx_bd_base + curr_tx;
status = GRETH_BD_EN;
if (skb->ip_summed == CHECKSUM_PARTIAL)
status |= GRETH_TXBD_CSALL;
status |= frag->size & GRETH_BD_LEN;
/* Wrap around descriptor ring */
if (curr_tx == GRETH_TXBD_NUM_MASK)
status |= GRETH_BD_WR;
/* More fragments left */
if (i < nr_frags - 1)
status |= GRETH_TXBD_MORE;
else
status |= GRETH_BD_IE; /* enable IRQ on last fragment */
greth_write_bd(&bdp->stat, status);
dma_addr = dma_map_page(greth->dev,
frag->page,
frag->page_offset,
frag->size,
DMA_TO_DEVICE);
if (unlikely(dma_mapping_error(greth->dev, dma_addr)))
goto frag_map_error;
greth_write_bd(&bdp->addr, dma_addr);
curr_tx = NEXT_TX(curr_tx);
}
wmb();
/* Enable the descriptor chain by enabling the first descriptor */
bdp = greth->tx_bd_base + greth->tx_next;
greth_write_bd(&bdp->stat, greth_read_bd(&bdp->stat) | GRETH_BD_EN);
greth->tx_next = curr_tx;
greth->tx_free -= nr_frags + 1;
wmb();
spin_lock_irqsave(&greth->devlock, flags); /*save from poll/irq*/
greth_enable_tx(greth);
spin_unlock_irqrestore(&greth->devlock, flags);
return NETDEV_TX_OK;
frag_map_error:
/* Unmap SKB mappings that succeeded and disable descriptor */
for (i = 0; greth->tx_next + i != curr_tx; i++) {
bdp = greth->tx_bd_base + greth->tx_next + i;
dma_unmap_single(greth->dev,
greth_read_bd(&bdp->addr),
greth_read_bd(&bdp->stat) & GRETH_BD_LEN,
DMA_TO_DEVICE);
greth_write_bd(&bdp->stat, 0);
}
map_error:
if (net_ratelimit())
dev_warn(greth->dev, "Could not create TX DMA mapping\n");
dev_kfree_skb(skb);
out:
return err;
}
