static int smc_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct smc_local *lp = netdev_priv(dev);
void __iomem *ioaddr = lp->base;
unsigned int numPages, poll_count, status;
unsigned long flags;
DBG(3, "%s: %s\n", dev->name, __func__);
BUG_ON(lp->pending_tx_skb != NULL);
numPages = ((skb->len & ~1) + (6 - 1)) >> 8;
if (unlikely(numPages > 7)) {
printk("%s: Far too big packet error.\n", dev->name);
dev->stats.tx_errors++;
dev->stats.tx_dropped++;
dev_kfree_skb(skb);
return NETDEV_TX_OK;
}
smc_special_lock(&lp->lock, flags);
SMC_SET_MMU_CMD(lp, MC_ALLOC | numPages);
poll_count = MEMORY_WAIT_TIME;
do {
status = SMC_GET_INT(lp);
if (status & IM_ALLOC_INT) {
SMC_ACK_INT(lp, IM_ALLOC_INT);
break;
}
} while (--poll_count);
smc_special_unlock(&lp->lock, flags);
lp->pending_tx_skb = skb;
if (!poll_count) {
netif_stop_queue(dev);
DBG(2, "%s: TX memory allocation deferred.\n", dev->name);
SMC_ENABLE_INT(lp, IM_ALLOC_INT);
} else {
smc_hardware_send_pkt((unsigned long)dev);
}
return NETDEV_TX_OK;
}
/*
* Since I am not sure if I will have enough room in the chip's ram
* to store the packet, I call this routine which either sends it
* now, or set the card to generates an interrupt when ready
* for the packet.
*/
static int smc_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
struct smc_local *lp = netdev_priv(dev);
void __iomem *ioaddr = lp->base;
unsigned int numPages, poll_count, status;
unsigned long flags;
DBG(3, "%s: %s\n", dev->name, __func__);
BUG_ON(lp->pending_tx_skb != NULL);
/*
* The MMU wants the number of pages to be the number of 256 bytes
* 'pages', minus 1 (since a packet can't ever have 0 pages :))
*
* The 91C111 ignores the size bits, but earlier models don't.
*
* Pkt size for allocating is data length +6 (for additional status
* words, length and ctl)
*
* If odd size then last byte is included in ctl word.
*/
numPages = ((skb->len & ~1) + (6 - 1)) >> 8;
if (unlikely(numPages > 7)) {
printk("%s: Far too big packet error.\n", dev->name);
dev->stats.tx_errors++;
dev->stats.tx_dropped++;
dev_kfree_skb(skb);
return NETDEV_TX_OK;
}
smc_special_lock(&lp->lock, flags);
/* now, try to allocate the memory */
SMC_SET_MMU_CMD(lp, MC_ALLOC | numPages);
/*
* Poll the chip for a short amount of time in case the
* allocation succeeds quickly.
*/
poll_count = MEMORY_WAIT_TIME;
do {
status = SMC_GET_INT(lp);
if (status & IM_ALLOC_INT) {
SMC_ACK_INT(lp, IM_ALLOC_INT);
break;
}
} while (--poll_count);
smc_special_unlock(&lp->lock, flags);
lp->pending_tx_skb = skb;
if (!poll_count) {
/* oh well, wait until the chip finds memory later */
netif_stop_queue(dev);
DBG(2, "%s: TX memory allocation deferred.\n", dev->name);
SMC_ENABLE_INT(lp, IM_ALLOC_INT);
} else {
/*
* Allocation succeeded: push packet to the chip's own memory
* immediately.
*/
smc_hardware_send_pkt((unsigned long)dev);
}
return NETDEV_TX_OK;
}
static void smc_hardware_send_pkt(unsigned long data)
{
struct net_device *dev = (struct net_device *)data;
struct smc_local *lp = netdev_priv(dev);
void __iomem *ioaddr = lp->base;
struct sk_buff *skb;
unsigned int packet_no, len;
unsigned char *buf;
unsigned long flags;
DBG(3, "%s: %s\n", dev->name, __func__);
if (!smc_special_trylock(&lp->lock, flags)) {
netif_stop_queue(dev);
tasklet_schedule(&lp->tx_task);
return;
}
skb = lp->pending_tx_skb;
if (unlikely(!skb)) {
smc_special_unlock(&lp->lock, flags);
return;
}
lp->pending_tx_skb = NULL;
packet_no = SMC_GET_AR(lp);
if (unlikely(packet_no & AR_FAILED)) {
printk("%s: Memory allocation failed.\n", dev->name);
dev->stats.tx_errors++;
dev->stats.tx_fifo_errors++;
smc_special_unlock(&lp->lock, flags);
goto done;
}
SMC_SET_PN(lp, packet_no);
SMC_SET_PTR(lp, PTR_AUTOINC);
buf = skb->data;
len = skb->len;
DBG(2, "%s: TX PNR 0x%x LENGTH 0x%04x (%d) BUF 0x%p\n",
dev->name, packet_no, len, len, buf);
PRINT_PKT(buf, len);
SMC_PUT_PKT_HDR(lp, 0, len + 6);
SMC_PUSH_DATA(lp, buf, len & ~1);
SMC_outw(((len & 1) ? (0x2000 | buf[len-1]) : 0), ioaddr, DATA_REG(lp));
if (THROTTLE_TX_PKTS)
netif_stop_queue(dev);
SMC_SET_MMU_CMD(lp, MC_ENQUEUE);
smc_special_unlock(&lp->lock, flags);
dev->trans_start = jiffies;
dev->stats.tx_packets++;
dev->stats.tx_bytes += len;
SMC_ENABLE_INT(lp, IM_TX_INT | IM_TX_EMPTY_INT);
done: if (!THROTTLE_TX_PKTS)
netif_wake_queue(dev);
dev_kfree_skb(skb);
}
/*
* This is called to actually send a packet to the chip.
*/
static void smc_hardware_send_pkt(unsigned long data)
{
struct net_device *dev = (struct net_device *)data;
struct smc_local *lp = netdev_priv(dev);
void __iomem *ioaddr = lp->base;
struct sk_buff *skb;
unsigned int packet_no, len;
unsigned char *buf;
unsigned long flags;
DBG(3, "%s: %s\n", dev->name, __func__);
if (!smc_special_trylock(&lp->lock, flags)) {
netif_stop_queue(dev);
tasklet_schedule(&lp->tx_task);
return;
}
skb = lp->pending_tx_skb;
if (unlikely(!skb)) {
smc_special_unlock(&lp->lock, flags);
return;
}
lp->pending_tx_skb = NULL;
packet_no = SMC_GET_AR(lp);
if (unlikely(packet_no & AR_FAILED)) {
printk("%s: Memory allocation failed.\n", dev->name);
dev->stats.tx_errors++;
dev->stats.tx_fifo_errors++;
smc_special_unlock(&lp->lock, flags);
goto done;
}
/* point to the beginning of the packet */
SMC_SET_PN(lp, packet_no);
SMC_SET_PTR(lp, PTR_AUTOINC);
buf = skb->data;
len = skb->len;
DBG(2, "%s: TX PNR 0x%x LENGTH 0x%04x (%d) BUF 0x%p\n",
dev->name, packet_no, len, len, buf);
PRINT_PKT(buf, len);
/*
* Send the packet length (+6 for status words, length, and ctl.
* The card will pad to 64 bytes with zeroes if packet is too small.
*/
SMC_PUT_PKT_HDR(lp, 0, len + 6);
/* send the actual data */
SMC_PUSH_DATA(lp, buf, len & ~1);
/* Send final ctl word with the last byte if there is one */
SMC_outw(((len & 1) ? (0x2000 | buf[len-1]) : 0), ioaddr, DATA_REG(lp));
/*
* If THROTTLE_TX_PKTS is set, we stop the queue here. This will
* have the effect of having at most one packet queued for TX
* in the chip's memory at all time.
*
* If THROTTLE_TX_PKTS is not set then the queue is stopped only
* when memory allocation (MC_ALLOC) does not succeed right away.
*/
if (THROTTLE_TX_PKTS)
netif_stop_queue(dev);
/* queue the packet for TX */
SMC_SET_MMU_CMD(lp, MC_ENQUEUE);
smc_special_unlock(&lp->lock, flags);
dev->trans_start = jiffies;
dev->stats.tx_packets++;
dev->stats.tx_bytes += len;
SMC_ENABLE_INT(lp, IM_TX_INT | IM_TX_EMPTY_INT);
done: if (!THROTTLE_TX_PKTS)
netif_wake_queue(dev);
dev_kfree_skb(skb);
}
