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 @@ greth_start_xmit(struct sk_buff *skb, struct net_device *dev) 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 @@ static int greth_poll(struct napi_struct *napi, int budget) 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 | diff --git a/drivers/net/ethernet/aeroflex/greth.h b/drivers/net/ethernet/aeroflex/greth.h index 232a622a85b7..ae16ac94daf8 100644 --- a/drivers/net/ethernet/aeroflex/greth.h +++ b/drivers/net/ethernet/aeroflex/greth.h @@ -107,7 +107,7 @@ struct greth_private { u16 tx_next; u16 tx_last; - u16 tx_free; + u16 tx_free; /* only used on 10/100Mbit */ u16 rx_cur; struct greth_regs *regs; /* Address of controller registers. */