diff options
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/net/ethernet/natsemi/sonic.c | 49 | ||||
| -rw-r--r-- | drivers/net/ethernet/natsemi/sonic.h | 1 |
2 files changed, 36 insertions, 14 deletions
diff --git a/drivers/net/ethernet/natsemi/sonic.c b/drivers/net/ethernet/natsemi/sonic.c index b339125b2f09..8a7cff516281 100644 --- a/drivers/net/ethernet/natsemi/sonic.c +++ b/drivers/net/ethernet/natsemi/sonic.c @@ -64,6 +64,8 @@ static int sonic_open(struct net_device *dev) netif_dbg(lp, ifup, dev, "%s: initializing sonic driver\n", __func__); + spin_lock_init(&lp->lock); + for (i = 0; i < SONIC_NUM_RRS; i++) { struct sk_buff *skb = netdev_alloc_skb(dev, SONIC_RBSIZE + 2); if (skb == NULL) { @@ -206,8 +208,6 @@ static void sonic_tx_timeout(struct net_device *dev) * wake the tx queue * Concurrently with all of this, the SONIC is potentially writing to * the status flags of the TDs. - * Until some mutual exclusion is added, this code will not work with SMP. However, - * MIPS Jazz machines and m68k Macs were all uni-processor machines. */ static int sonic_send_packet(struct sk_buff *skb, struct net_device *dev) @@ -215,7 +215,8 @@ static int sonic_send_packet(struct sk_buff *skb, struct net_device *dev) struct sonic_local *lp = netdev_priv(dev); dma_addr_t laddr; int length; - int entry = lp->next_tx; + int entry; + unsigned long flags; netif_dbg(lp, tx_queued, dev, "%s: skb=%p\n", __func__, skb); @@ -237,6 +238,10 @@ static int sonic_send_packet(struct sk_buff *skb, struct net_device *dev) return NETDEV_TX_OK; } + spin_lock_irqsave(&lp->lock, flags); + + entry = lp->next_tx; + sonic_tda_put(dev, entry, SONIC_TD_STATUS, 0); /* clear status */ sonic_tda_put(dev, entry, SONIC_TD_FRAG_COUNT, 1); /* single fragment */ sonic_tda_put(dev, entry, SONIC_TD_PKTSIZE, length); /* length of packet */ @@ -246,10 +251,6 @@ static int sonic_send_packet(struct sk_buff *skb, struct net_device *dev) sonic_tda_put(dev, entry, SONIC_TD_LINK, sonic_tda_get(dev, entry, SONIC_TD_LINK) | SONIC_EOL); - /* - * Must set tx_skb[entry] only after clearing status, and - * before clearing EOL and before stopping queue - */ wmb(); lp->tx_len[entry] = length; lp->tx_laddr[entry] = laddr; @@ -272,6 +273,8 @@ static int sonic_send_packet(struct sk_buff *skb, struct net_device *dev) SONIC_WRITE(SONIC_CMD, SONIC_CR_TXP); + spin_unlock_irqrestore(&lp->lock, flags); + return NETDEV_TX_OK; } @@ -284,9 +287,21 @@ static irqreturn_t sonic_interrupt(int irq, void *dev_id) struct net_device *dev = dev_id; struct sonic_local *lp = netdev_priv(dev); int status; + unsigned long flags; + + /* The lock has two purposes. Firstly, it synchronizes sonic_interrupt() + * with sonic_send_packet() so that the two functions can share state. + * Secondly, it makes sonic_interrupt() re-entrant, as that is required + * by macsonic which must use two IRQs with different priority levels. + */ + spin_lock_irqsave(&lp->lock, flags); + + status = SONIC_READ(SONIC_ISR) & SONIC_IMR_DEFAULT; + if (!status) { + spin_unlock_irqrestore(&lp->lock, flags); - if (!(status = SONIC_READ(SONIC_ISR) & SONIC_IMR_DEFAULT)) return IRQ_NONE; + } do { if (status & SONIC_INT_PKTRX) { @@ -300,11 +315,12 @@ static irqreturn_t sonic_interrupt(int irq, void *dev_id) int td_status; int freed_some = 0; - /* At this point, cur_tx is the index of a TD that is one of: - * unallocated/freed (status set & tx_skb[entry] clear) - * allocated and sent (status set & tx_skb[entry] set ) - * allocated and not yet sent (status clear & tx_skb[entry] set ) - * still being allocated by sonic_send_packet (status clear & tx_skb[entry] clear) + /* The state of a Transmit Descriptor may be inferred + * from { tx_skb[entry], td_status } as follows. + * { clear, clear } => the TD has never been used + * { set, clear } => the TD was handed to SONIC + * { set, set } => the TD was handed back + * { clear, set } => the TD is available for re-use */ netif_dbg(lp, intr, dev, "%s: tx done\n", __func__); @@ -406,7 +422,12 @@ static irqreturn_t sonic_interrupt(int irq, void *dev_id) /* load CAM done */ if (status & SONIC_INT_LCD) SONIC_WRITE(SONIC_ISR, SONIC_INT_LCD); /* clear the interrupt */ - } while((status = SONIC_READ(SONIC_ISR) & SONIC_IMR_DEFAULT)); + + status = SONIC_READ(SONIC_ISR) & SONIC_IMR_DEFAULT; + } while (status); + + spin_unlock_irqrestore(&lp->lock, flags); + return IRQ_HANDLED; } diff --git a/drivers/net/ethernet/natsemi/sonic.h b/drivers/net/ethernet/natsemi/sonic.h index 2b27f7049acb..f9506863e9d1 100644 --- a/drivers/net/ethernet/natsemi/sonic.h +++ b/drivers/net/ethernet/natsemi/sonic.h @@ -322,6 +322,7 @@ struct sonic_local { int msg_enable; struct device *device; /* generic device */ struct net_device_stats stats; + spinlock_t lock; }; #define TX_TIMEOUT (3 * HZ) |