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path: root/drivers/net/ethernet/aeroflex/greth.c
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Diffstat (limited to 'drivers/net/ethernet/aeroflex/greth.c')
-rw-r--r--drivers/net/ethernet/aeroflex/greth.c86
1 files changed, 48 insertions, 38 deletions
diff --git a/drivers/net/ethernet/aeroflex/greth.c b/drivers/net/ethernet/aeroflex/greth.c
index 23578dfee249..3005155e412b 100644
--- a/drivers/net/ethernet/aeroflex/greth.c
+++ b/drivers/net/ethernet/aeroflex/greth.c
@@ -123,6 +123,12 @@ static inline void greth_enable_tx(struct greth_private *greth)
GRETH_REGORIN(greth->regs->control, GRETH_TXEN);
}
+static inline void greth_enable_tx_and_irq(struct greth_private *greth)
+{
+ wmb(); /* BDs must been written to memory before enabling TX */
+ GRETH_REGORIN(greth->regs->control, GRETH_TXEN | GRETH_TXI);
+}
+
static inline void greth_disable_tx(struct greth_private *greth)
{
GRETH_REGANDIN(greth->regs->control, ~GRETH_TXEN);
@@ -447,29 +453,30 @@ out:
return err;
}
+static inline u16 greth_num_free_bds(u16 tx_last, u16 tx_next)
+{
+ if (tx_next < tx_last)
+ return (tx_last - tx_next) - 1;
+ else
+ return GRETH_TXBD_NUM - (tx_next - tx_last) - 1;
+}
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;
+ u32 status, dma_addr;
int curr_tx, nr_frags, i, err = NETDEV_TX_OK;
unsigned long flags;
+ u16 tx_last;
nr_frags = skb_shinfo(skb)->nr_frags;
+ tx_last = greth->tx_last;
+ rmb(); /* tx_last is updated by the poll task */
- /* 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);
+ if (greth_num_free_bds(tx_last, greth->tx_next) < nr_frags + 1) {
netif_stop_queue(dev);
- spin_unlock_irqrestore(&greth->devlock, flags);
err = NETDEV_TX_BUSY;
goto out;
}
@@ -488,6 +495,8 @@ greth_start_xmit_gbit(struct sk_buff *skb, struct net_device *dev)
/* Linear buf */
if (nr_frags != 0)
status = GRETH_TXBD_MORE;
+ else
+ status = GRETH_BD_IE;
if (skb->ip_summed == CHECKSUM_PARTIAL)
status |= GRETH_TXBD_CSALL;
@@ -545,14 +554,12 @@ greth_start_xmit_gbit(struct sk_buff *skb, struct net_device *dev)
/* 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();
+ greth_write_bd(&bdp->stat,
+ greth_read_bd(&bdp->stat) | GRETH_BD_EN);
spin_lock_irqsave(&greth->devlock, flags); /*save from poll/irq*/
- greth_enable_tx(greth);
+ greth->tx_next = curr_tx;
+ greth_enable_tx_and_irq(greth);
spin_unlock_irqrestore(&greth->devlock, flags);
return NETDEV_TX_OK;
@@ -648,7 +655,6 @@ static void greth_clean_tx(struct net_device *dev)
if (greth->tx_free > 0) {
netif_wake_queue(dev);
}
-
}
static inline void greth_update_tx_stats(struct net_device *dev, u32 stat)
@@ -670,20 +676,22 @@ static void greth_clean_tx_gbit(struct net_device *dev)
{
struct greth_private *greth;
struct greth_bd *bdp, *bdp_last_frag;
- struct sk_buff *skb;
+ struct sk_buff *skb = NULL;
u32 stat;
int nr_frags, i;
+ u16 tx_last;
greth = netdev_priv(dev);
+ tx_last = greth->tx_last;
- while (greth->tx_free < GRETH_TXBD_NUM) {
+ while (tx_last != greth->tx_next) {
- skb = greth->tx_skbuff[greth->tx_last];
+ skb = greth->tx_skbuff[tx_last];
nr_frags = skb_shinfo(skb)->nr_frags;
/* We only clean fully completed SKBs */
- bdp_last_frag = greth->tx_bd_base + SKIP_TX(greth->tx_last, nr_frags);
+ bdp_last_frag = greth->tx_bd_base + SKIP_TX(tx_last, nr_frags);
GRETH_REGSAVE(greth->regs->status, GRETH_INT_TE | GRETH_INT_TX);
mb();
@@ -692,14 +700,14 @@ static void greth_clean_tx_gbit(struct net_device *dev)
if (stat & GRETH_BD_EN)
break;
- greth->tx_skbuff[greth->tx_last] = NULL;
+ greth->tx_skbuff[tx_last] = NULL;
greth_update_tx_stats(dev, stat);
dev->stats.tx_bytes += skb->len;
- bdp = greth->tx_bd_base + greth->tx_last;
+ bdp = greth->tx_bd_base + tx_last;
- greth->tx_last = NEXT_TX(greth->tx_last);
+ tx_last = NEXT_TX(tx_last);
dma_unmap_single(greth->dev,
greth_read_bd(&bdp->addr),
@@ -708,21 +716,26 @@ static void greth_clean_tx_gbit(struct net_device *dev)
for (i = 0; i < nr_frags; i++) {
skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
- bdp = greth->tx_bd_base + greth->tx_last;
+ bdp = greth->tx_bd_base + tx_last;
dma_unmap_page(greth->dev,
greth_read_bd(&bdp->addr),
skb_frag_size(frag),
DMA_TO_DEVICE);
- greth->tx_last = NEXT_TX(greth->tx_last);
+ tx_last = NEXT_TX(tx_last);
}
- greth->tx_free += nr_frags+1;
dev_kfree_skb(skb);
}
+ if (skb) { /* skb is set only if the above while loop was entered */
+ wmb();
+ greth->tx_last = tx_last;
- if (netif_queue_stopped(dev) && (greth->tx_free > (MAX_SKB_FRAGS+1)))
- netif_wake_queue(dev);
+ if (netif_queue_stopped(dev) &&
+ (greth_num_free_bds(tx_last, greth->tx_next) >
+ (MAX_SKB_FRAGS+1)))
+ netif_wake_queue(dev);
+ }
}
static int greth_rx(struct net_device *dev, int limit)
@@ -965,16 +978,12 @@ static int greth_poll(struct napi_struct *napi, int budget)
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) {
+ greth_clean_tx_gbit(greth->netdev);
work_done += greth_rx_gbit(greth->netdev, budget - work_done);
} else {
+ if (netif_queue_stopped(greth->netdev))
+ greth_clean_tx(greth->netdev);
work_done += greth_rx(greth->netdev, budget - work_done);
}
@@ -983,7 +992,8 @@ restart_txrx_poll:
spin_lock_irqsave(&greth->devlock, flags);
ctrl = GRETH_REGLOAD(greth->regs->control);
- if (netif_queue_stopped(greth->netdev)) {
+ if ((greth->gbit_mac && (greth->tx_last != greth->tx_next)) ||
+ (!greth->gbit_mac && netif_queue_stopped(greth->netdev))) {
GRETH_REGSAVE(greth->regs->control,
ctrl | GRETH_TXI | GRETH_RXI);
mask = GRETH_INT_RX | GRETH_INT_RE |