dl2k.c

linux 内核源代码

	np->timer.function = &rio_timer;
	add_timer (&np->timer);

	/* Start Tx/Rx */
	writel (readl (ioaddr + MACCtrl) | StatsEnable | RxEnable | TxEnable,
			ioaddr + MACCtrl);

	macctrl = 0;
	macctrl |= (np->vlan) ? AutoVLANuntagging : 0;
	macctrl |= (np->full_duplex) ? DuplexSelect : 0;
	macctrl |= (np->tx_flow) ? TxFlowControlEnable : 0;
	macctrl |= (np->rx_flow) ? RxFlowControlEnable : 0;
	writew(macctrl,	ioaddr + MACCtrl);

	netif_start_queue (dev);

	/* Enable default interrupts */
	EnableInt ();
	return 0;
}

static void
rio_timer (unsigned long data)
{
	struct net_device *dev = (struct net_device *)data;
	struct netdev_private *np = netdev_priv(dev);
	unsigned int entry;
	int next_tick = 1*HZ;
	unsigned long flags;

	spin_lock_irqsave(&np->rx_lock, flags);
	/* Recover rx ring exhausted error */
	if (np->cur_rx - np->old_rx >= RX_RING_SIZE) {
		printk(KERN_INFO "Try to recover rx ring exhausted...\n");
		/* Re-allocate skbuffs to fill the descriptor ring */
		for (; np->cur_rx - np->old_rx > 0; np->old_rx++) {
			struct sk_buff *skb;
			entry = np->old_rx % RX_RING_SIZE;
			/* Dropped packets don't need to re-allocate */
			if (np->rx_skbuff[entry] == NULL) {
				skb = dev_alloc_skb (np->rx_buf_sz);
				if (skb == NULL) {
					np->rx_ring[entry].fraginfo = 0;
					printk (KERN_INFO
						"%s: Still unable to re-allocate Rx skbuff.#%d\n",
						dev->name, entry);
					break;
				}
				np->rx_skbuff[entry] = skb;
				/* 16 byte align the IP header */
				skb_reserve (skb, 2);
				np->rx_ring[entry].fraginfo =
				    cpu_to_le64 (pci_map_single
					 (np->pdev, skb->data, np->rx_buf_sz,
					  PCI_DMA_FROMDEVICE));
			}
			np->rx_ring[entry].fraginfo |=
			    cpu_to_le64((u64)np->rx_buf_sz << 48);
			np->rx_ring[entry].status = 0;
		} /* end for */
	} /* end if */
	spin_unlock_irqrestore (&np->rx_lock, flags);
	np->timer.expires = jiffies + next_tick;
	add_timer(&np->timer);
}

static void
rio_tx_timeout (struct net_device *dev)
{
	long ioaddr = dev->base_addr;

	printk (KERN_INFO "%s: Tx timed out (%4.4x), is buffer full?\n",
		dev->name, readl (ioaddr + TxStatus));
	rio_free_tx(dev, 0);
	dev->if_port = 0;
	dev->trans_start = jiffies;
}

 /* allocate and initialize Tx and Rx descriptors */
static void
alloc_list (struct net_device *dev)
{
	struct netdev_private *np = netdev_priv(dev);
	int i;

	np->cur_rx = np->cur_tx = 0;
	np->old_rx = np->old_tx = 0;
	np->rx_buf_sz = (dev->mtu <= 1500 ? PACKET_SIZE : dev->mtu + 32);

	/* Initialize Tx descriptors, TFDListPtr leaves in start_xmit(). */
	for (i = 0; i < TX_RING_SIZE; i++) {
		np->tx_skbuff[i] = NULL;
		np->tx_ring[i].status = cpu_to_le64 (TFDDone);
		np->tx_ring[i].next_desc = cpu_to_le64 (np->tx_ring_dma +
					      ((i+1)%TX_RING_SIZE) *
					      sizeof (struct netdev_desc));
	}

	/* Initialize Rx descriptors */
	for (i = 0; i < RX_RING_SIZE; i++) {
		np->rx_ring[i].next_desc = cpu_to_le64 (np->rx_ring_dma +
						((i + 1) % RX_RING_SIZE) *
						sizeof (struct netdev_desc));
		np->rx_ring[i].status = 0;
		np->rx_ring[i].fraginfo = 0;
		np->rx_skbuff[i] = NULL;
	}

	/* Allocate the rx buffers */
	for (i = 0; i < RX_RING_SIZE; i++) {
		/* Allocated fixed size of skbuff */
		struct sk_buff *skb = dev_alloc_skb (np->rx_buf_sz);
		np->rx_skbuff[i] = skb;
		if (skb == NULL) {
			printk (KERN_ERR
				"%s: alloc_list: allocate Rx buffer error! ",
				dev->name);
			break;
		}
		skb_reserve (skb, 2);	/* 16 byte align the IP header. */
		/* Rubicon now supports 40 bits of addressing space. */
		np->rx_ring[i].fraginfo =
		    cpu_to_le64 ( pci_map_single (
			 	  np->pdev, skb->data, np->rx_buf_sz,
				  PCI_DMA_FROMDEVICE));
		np->rx_ring[i].fraginfo |= cpu_to_le64((u64)np->rx_buf_sz << 48);
	}

	/* Set RFDListPtr */
	writel (np->rx_ring_dma, dev->base_addr + RFDListPtr0);
	writel (0, dev->base_addr + RFDListPtr1);

	return;
}

static int
start_xmit (struct sk_buff *skb, struct net_device *dev)
{
	struct netdev_private *np = netdev_priv(dev);
	struct netdev_desc *txdesc;
	unsigned entry;
	u32 ioaddr;
	u64 tfc_vlan_tag = 0;

	if (np->link_status == 0) {	/* Link Down */
		dev_kfree_skb(skb);
		return 0;
	}
	ioaddr = dev->base_addr;
	entry = np->cur_tx % TX_RING_SIZE;
	np->tx_skbuff[entry] = skb;
	txdesc = &np->tx_ring[entry];

#if 0
	if (skb->ip_summed == CHECKSUM_PARTIAL) {
		txdesc->status |=
		    cpu_to_le64 (TCPChecksumEnable | UDPChecksumEnable |
				 IPChecksumEnable);
	}
#endif
	if (np->vlan) {
		tfc_vlan_tag = VLANTagInsert |
		    ((u64)np->vlan << 32) |
		    ((u64)skb->priority << 45);
	}
	txdesc->fraginfo = cpu_to_le64 (pci_map_single (np->pdev, skb->data,
							skb->len,
							PCI_DMA_TODEVICE));
	txdesc->fraginfo |= cpu_to_le64((u64)skb->len << 48);

	/* DL2K bug: DMA fails to get next descriptor ptr in 10Mbps mode
	 * Work around: Always use 1 descriptor in 10Mbps mode */
	if (entry % np->tx_coalesce == 0 || np->speed == 10)
		txdesc->status = cpu_to_le64 (entry | tfc_vlan_tag |
					      WordAlignDisable |
					      TxDMAIndicate |
					      (1 << FragCountShift));
	else
		txdesc->status = cpu_to_le64 (entry | tfc_vlan_tag |
					      WordAlignDisable |
					      (1 << FragCountShift));

	/* TxDMAPollNow */
	writel (readl (ioaddr + DMACtrl) | 0x00001000, ioaddr + DMACtrl);
	/* Schedule ISR */
	writel(10000, ioaddr + CountDown);
	np->cur_tx = (np->cur_tx + 1) % TX_RING_SIZE;
	if ((np->cur_tx - np->old_tx + TX_RING_SIZE) % TX_RING_SIZE
			< TX_QUEUE_LEN - 1 && np->speed != 10) {
		/* do nothing */
	} else if (!netif_queue_stopped(dev)) {
		netif_stop_queue (dev);
	}

	/* The first TFDListPtr */
	if (readl (dev->base_addr + TFDListPtr0) == 0) {
		writel (np->tx_ring_dma + entry * sizeof (struct netdev_desc),
			dev->base_addr + TFDListPtr0);
		writel (0, dev->base_addr + TFDListPtr1);
	}

	/* NETDEV WATCHDOG timer */
	dev->trans_start = jiffies;
	return 0;
}

static irqreturn_t
rio_interrupt (int irq, void *dev_instance)
{
	struct net_device *dev = dev_instance;
	struct netdev_private *np;
	unsigned int_status;
	long ioaddr;
	int cnt = max_intrloop;
	int handled = 0;

	ioaddr = dev->base_addr;
	np = netdev_priv(dev);
	while (1) {
		int_status = readw (ioaddr + IntStatus);
		writew (int_status, ioaddr + IntStatus);
		int_status &= DEFAULT_INTR;
		if (int_status == 0 || --cnt < 0)
			break;
		handled = 1;
		/* Processing received packets */
		if (int_status & RxDMAComplete)
			receive_packet (dev);
		/* TxDMAComplete interrupt */
		if ((int_status & (TxDMAComplete|IntRequested))) {
			int tx_status;
			tx_status = readl (ioaddr + TxStatus);
			if (tx_status & 0x01)
				tx_error (dev, tx_status);
			/* Free used tx skbuffs */
			rio_free_tx (dev, 1);
		}

		/* Handle uncommon events */
		if (int_status &
		    (HostError | LinkEvent | UpdateStats))
			rio_error (dev, int_status);
	}
	if (np->cur_tx != np->old_tx)
		writel (100, ioaddr + CountDown);
	return IRQ_RETVAL(handled);
}

static inline dma_addr_t desc_to_dma(struct netdev_desc *desc)
{
	return le64_to_cpu(desc->fraginfo) & DMA_48BIT_MASK;
}

static void
rio_free_tx (struct net_device *dev, int irq)
{
	struct netdev_private *np = netdev_priv(dev);
	int entry = np->old_tx % TX_RING_SIZE;
	int tx_use = 0;
	unsigned long flag = 0;

	if (irq)
		spin_lock(&np->tx_lock);
	else
		spin_lock_irqsave(&np->tx_lock, flag);

	/* Free used tx skbuffs */
	while (entry != np->cur_tx) {
		struct sk_buff *skb;

		if (!(np->tx_ring[entry].status & cpu_to_le64(TFDDone)))
			break;
		skb = np->tx_skbuff[entry];
		pci_unmap_single (np->pdev,
				  desc_to_dma(&np->tx_ring[entry]),
				  skb->len, PCI_DMA_TODEVICE);
		if (irq)
			dev_kfree_skb_irq (skb);
		else
			dev_kfree_skb (skb);

		np->tx_skbuff[entry] = NULL;
		entry = (entry + 1) % TX_RING_SIZE;
		tx_use++;
	}
	if (irq)
		spin_unlock(&np->tx_lock);
	else
		spin_unlock_irqrestore(&np->tx_lock, flag);
	np->old_tx = entry;

	/* If the ring is no longer full, clear tx_full and
	   call netif_wake_queue() */

	if (netif_queue_stopped(dev) &&
	    ((np->cur_tx - np->old_tx + TX_RING_SIZE) % TX_RING_SIZE
	    < TX_QUEUE_LEN - 1 || np->speed == 10)) {
		netif_wake_queue (dev);
	}
}

static void
tx_error (struct net_device *dev, int tx_status)
{
	struct netdev_private *np;
	long ioaddr = dev->base_addr;
	int frame_id;
	int i;

	np = netdev_priv(dev);

	frame_id = (tx_status & 0xffff0000);
	printk (KERN_ERR "%s: Transmit error, TxStatus %4.4x, FrameId %d.\n",
		dev->name, tx_status, frame_id);
	np->stats.tx_errors++;
	/* Ttransmit Underrun */
	if (tx_status & 0x10) {
		np->stats.tx_fifo_errors++;
		writew (readw (ioaddr + TxStartThresh) + 0x10,
			ioaddr + TxStartThresh);
		/* Transmit Underrun need to set TxReset, DMARest, FIFOReset */
		writew (TxReset | DMAReset | FIFOReset | NetworkReset,
			ioaddr + ASICCtrl + 2);
		/* Wait for ResetBusy bit clear */
		for (i = 50; i > 0; i--) {
			if ((readw (ioaddr + ASICCtrl + 2) & ResetBusy) == 0)
				break;
			mdelay (1);
		}
		rio_free_tx (dev, 1);
		/* Reset TFDListPtr */
		writel (np->tx_ring_dma +
			np->old_tx * sizeof (struct netdev_desc),
			dev->base_addr + TFDListPtr0);
		writel (0, dev->base_addr + TFDListPtr1);

		/* Let TxStartThresh stay default value */
	}
	/* Late Collision */
	if (tx_status & 0x04) {
		np->stats.tx_fifo_errors++;
		/* TxReset and clear FIFO */
		writew (TxReset | FIFOReset, ioaddr + ASICCtrl + 2);
		/* Wait reset done */
		for (i = 50; i > 0; i--) {
			if ((readw (ioaddr + ASICCtrl + 2) & ResetBusy) == 0)
				break;
			mdelay (1);
		}
		/* Let TxStartThresh stay default value */
	}
	/* Maximum Collisions */
#ifdef ETHER_STATS
	if (tx_status & 0x08)
		np->stats.collisions16++;
#else
	if (tx_status & 0x08)
		np->stats.collisions++;
#endif
	/* Restart the Tx */
	writel (readw (dev->base_addr + MACCtrl) | TxEnable, ioaddr + MACCtrl);
}

static int
receive_packet (struct net_device *dev)
{
	struct netdev_private *np = netdev_priv(dev);
	int entry = np->cur_rx % RX_RING_SIZE;
	int cnt = 30;

	/* If RFDDone, FrameStart and FrameEnd set, there is a new packet in. */
	while (1) {
		struct netdev_desc *desc = &np->rx_ring[entry];
		int pkt_len;
		u64 frame_status;

		if (!(desc->status & cpu_to_le64(RFDDone)) ||
		    !(desc->status & cpu_to_le64(FrameStart)) ||
		    !(desc->status & cpu_to_le64(FrameEnd)))
			break;

		/* Chip omits the CRC. */
		frame_status = le64_to_cpu(desc->status);
		pkt_len = frame_status & 0xffff;
		if (--cnt < 0)
			break;
		/* Update rx error statistics, drop packet. */
		if (frame_status & RFS_Errors) {
			np->stats.rx_errors++;
			if (frame_status & (RxRuntFrame | RxLengthError))
				np->stats.rx_length_errors++;
			if (frame_status & RxFCSError)
				np->stats.rx_crc_errors++;
			if (frame_status & RxAlignmentError && np->speed != 1000)
				np->stats.rx_frame_errors++;
			if (frame_status & RxFIFOOverrun)
	 			np->stats.rx_fifo_errors++;
		} else {
			struct sk_buff *skb;

			/* Small skbuffs for short packets */
			if (pkt_len > copy_thresh) {
				pci_unmap_single (np->pdev,
						  desc_to_dma(desc),
						  np->rx_buf_sz,
						  PCI_DMA_FROMDEVICE);
				skb_put (skb = np->rx_skbuff[entry], pkt_len);
				np->rx_skbuff[entry] = NULL;
			} else if ((skb = dev_alloc_skb (pkt_len + 2)) != NULL) {
				pci_dma_sync_single_for_cpu(np->pdev,
							    desc_to_dma(desc),
							    np->rx_buf_sz,
							    PCI_DMA_FROMDEVICE);
				/* 16 byte align the IP header */
				skb_reserve (skb, 2);
				skb_copy_to_linear_data (skb,
						  np->rx_skbuff[entry]->data,
						  pkt_len);
				skb_put (skb, pkt_len);
				pci_dma_sync_single_for_device(np->pdev,
							       desc_to_dma(desc),
							       np->rx_buf_sz,
							       PCI_DMA_FROMDEVICE);
			}
			skb->protocol = eth_type_trans (skb, dev);
#if 0
			/* Checksum done by hw, but csum value unavailable. */
			if (np->pdev->pci_rev_id >= 0x0c &&
				!(frame_status & (TCPError | UDPError | IPError))) {
				skb->ip_summed = CHECKSUM_UNNECESSARY;
			}
#endif
			netif_rx (skb);
			dev->last_rx = jiffies;
		}
		entry = (entry + 1) % RX_RING_SIZE;
	}
	spin_lock(&np->rx_lock);
	np->cur_rx = entry;
	/* Re-allocate skbuffs to fill the descriptor ring */
	entry = np->old_rx;
	while (entry != np->cur_rx) {
		struct sk_buff *skb;
		/* Dropped packets don't need to re-allocate */
		if (np->rx_skbuff[entry] == NULL) {
			skb = dev_alloc_skb (np->rx_buf_sz);
			if (skb == NULL) {
				np->rx_ring[entry].fraginfo = 0;
				printk (KERN_INFO
					"%s: receive_packet: "
					"Unable to re-allocate Rx skbuff.#%d\n",
					dev->name, entry);
				break;
			}
			np->rx_skbuff[entry] = skb;
			/* 16 byte align the IP header */
			skb_reserve (skb, 2);
			np->rx_ring[entry].fraginfo =
			    cpu_to_le64 (pci_map_single
					 (np->pdev, skb->data, np->rx_buf_sz,
					  PCI_DMA_FROMDEVICE));