diff options
| -rw-r--r-- | drivers/atm/solos-pci.c | 53 |
1 files changed, 28 insertions, 25 deletions
diff --git a/drivers/atm/solos-pci.c b/drivers/atm/solos-pci.c index 5e228a3f7502..e7691b3328f9 100644 --- a/drivers/atm/solos-pci.c +++ b/drivers/atm/solos-pci.c @@ -140,7 +140,7 @@ module_param(fpga_upgrade, int, 0444); static void fpga_queue(struct solos_card *card, int port, struct sk_buff *skb, struct atm_vcc *vcc); -static int fpga_tx(struct solos_card *); +static uint32_t fpga_tx(struct solos_card *); static irqreturn_t solos_irq(int irq, void *dev_id); static struct atm_vcc* find_vcc(struct atm_dev *dev, short vpi, int vci); static int list_vccs(int vci); @@ -438,8 +438,6 @@ static int send_command(struct solos_card *card, int dev, const char *buf, size_ struct sk_buff *skb; struct pkt_hdr *header; -// dev_dbg(&card->dev->dev, "size: %d\n", size); - if (size > (BUF_SIZE - sizeof(*header))) { dev_dbg(&card->dev->dev, "Command is too big. Dropping request\n"); return 0; @@ -574,9 +572,9 @@ static irqreturn_t solos_irq(int irq, void *dev_id) struct solos_card *card = dev_id; int handled = 1; - //ACK IRQ iowrite32(0, card->config_regs + IRQ_CLEAR); + /* If we're up and running, just kick the tasklet to process TX/RX */ if (card->atmdev[0]) tasklet_schedule(&card->tlet); else @@ -588,16 +586,16 @@ static irqreturn_t solos_irq(int irq, void *dev_id) void solos_bh(unsigned long card_arg) { struct solos_card *card = (void *)card_arg; - int port; uint32_t card_flags; uint32_t rx_done = 0; + int port; - card_flags = ioread32(card->config_regs + FLAGS_ADDR); - - /* The TX bits are set if the channel is busy; clear if not. We want to - invoke fpga_tx() unless _all_ the bits for active channels are set */ - if ((card_flags & card->tx_mask) != card->tx_mask) - fpga_tx(card); + /* + * Since fpga_tx() is going to need to read the flags under its lock, + * it can return them to us so that we don't have to hit PCI MMIO + * again for the same information + */ + card_flags = fpga_tx(card); for (port = 0; port < card->nr_ports; port++) { if (card_flags & (0x10 << port)) { @@ -892,9 +890,8 @@ static void fpga_queue(struct solos_card *card, int port, struct sk_buff *skb, spin_lock_irqsave(&card->tx_queue_lock, flags); old_len = skb_queue_len(&card->tx_queue[port]); skb_queue_tail(&card->tx_queue[port], skb); - if (!old_len) { + if (!old_len) card->tx_mask |= (1 << port); - } spin_unlock_irqrestore(&card->tx_queue_lock, flags); /* Theoretically we could just schedule the tasklet here, but @@ -903,9 +900,9 @@ static void fpga_queue(struct solos_card *card, int port, struct sk_buff *skb, fpga_tx(card); } -static int fpga_tx(struct solos_card *card) +static uint32_t fpga_tx(struct solos_card *card) { - uint32_t tx_pending; + uint32_t tx_pending, card_flags; uint32_t tx_started = 0; struct sk_buff *skb; struct atm_vcc *vcc; @@ -913,19 +910,24 @@ static int fpga_tx(struct solos_card *card) unsigned long flags; spin_lock_irqsave(&card->tx_lock, flags); - - tx_pending = ioread32(card->config_regs + FLAGS_ADDR) & card->tx_mask; - - dev_vdbg(&card->dev->dev, "TX Flags are %X\n", tx_pending); - - for (port = 0; port < card->nr_ports; port++) { - if (card->atmdev[port] && !(tx_pending & (1 << port))) { + + card_flags = ioread32(card->config_regs + FLAGS_ADDR); + /* + * The queue lock is required for _writing_ to tx_mask, but we're + * OK to read it here without locking. The only potential update + * that we could race with is in fpga_queue() where it sets a bit + * for a new port... but it's going to call this function again if + * it's doing that, anyway. + */ + tx_pending = card->tx_mask & ~card_flags; + + for (port = 0; tx_pending; tx_pending >>= 1, port++) { + if (tx_pending & 1) { struct sk_buff *oldskb = card->tx_skb[port]; - if (oldskb) pci_unmap_single(card->dev, SKB_CB(oldskb)->dma_addr, oldskb->len, PCI_DMA_TODEVICE); - + spin_lock(&card->tx_queue_lock); skb = skb_dequeue(&card->tx_queue[port]); if (!skb) @@ -966,8 +968,9 @@ static int fpga_tx(struct solos_card *card) if (tx_started) iowrite32(tx_started, card->config_regs + FLAGS_ADDR); + out: spin_unlock_irqrestore(&card->tx_lock, flags); - return 0; + return card_flags; } static int psend(struct atm_vcc *vcc, struct sk_buff *skb) |