epic100.c

来自「Linux Kernel 2.6.9 for OMAP1710」· C语言 代码 · 共 1,688 行 · 第 1/4 页

	}

	/* Remove the packets on the Rx queue. */
	epic_rx(dev, RX_RING_SIZE);
}

static void epic_restart(struct net_device *dev)
{
	long ioaddr = dev->base_addr;
	struct epic_private *ep = dev->priv;
	int i;

	/* Soft reset the chip. */
	outl(0x4001, ioaddr + GENCTL);

	printk(KERN_DEBUG "%s: Restarting the EPIC chip, Rx %d/%d Tx %d/%d.\n",
		   dev->name, ep->cur_rx, ep->dirty_rx, ep->dirty_tx, ep->cur_tx);
	udelay(1);

	/* This magic is documented in SMSC app note 7.15 */
	for (i = 16; i > 0; i--)
		outl(0x0008, ioaddr + TEST1);

#if defined(__powerpc__) || defined(__sparc__)		/* Big endian */
	outl(0x0432 | (RX_FIFO_THRESH<<8), ioaddr + GENCTL);
#else
	outl(0x0412 | (RX_FIFO_THRESH<<8), ioaddr + GENCTL);
#endif
	outl(dev->if_port == 1 ? 0x13 : 0x12, ioaddr + MIICfg);
	if (ep->chip_flags & MII_PWRDWN)
		outl((inl(ioaddr + NVCTL) & ~0x003C) | 0x4800, ioaddr + NVCTL);

	for (i = 0; i < 3; i++)
		outl(cpu_to_le16(((u16*)dev->dev_addr)[i]), ioaddr + LAN0 + i*4);

	ep->tx_threshold = TX_FIFO_THRESH;
	outl(ep->tx_threshold, ioaddr + TxThresh);
	outl(ep->mii.full_duplex ? 0x7F : 0x79, ioaddr + TxCtrl);
	outl(ep->rx_ring_dma + (ep->cur_rx%RX_RING_SIZE)*
		sizeof(struct epic_rx_desc), ioaddr + PRxCDAR);
	outl(ep->tx_ring_dma + (ep->dirty_tx%TX_RING_SIZE)*
		 sizeof(struct epic_tx_desc), ioaddr + PTxCDAR);

	/* Start the chip's Rx process. */
	set_rx_mode(dev);
	outl(StartRx | RxQueued, ioaddr + COMMAND);

	/* Enable interrupts by setting the interrupt mask. */
	outl((ep->chip_flags & TYPE2_INTR ? PCIBusErr175 : PCIBusErr170)
		 | CntFull | TxUnderrun
		 | RxError | RxHeader | EpicNapiEvent, ioaddr + INTMASK);

	printk(KERN_DEBUG "%s: epic_restart() done, cmd status %4.4x, ctl %4.4x"
		   " interrupt %4.4x.\n",
		   dev->name, (int)inl(ioaddr + COMMAND), (int)inl(ioaddr + GENCTL),
		   (int)inl(ioaddr + INTSTAT));
	return;
}

static void check_media(struct net_device *dev)
{
	struct epic_private *ep = dev->priv;
	long ioaddr = dev->base_addr;
	int mii_lpa = ep->mii_phy_cnt ? mdio_read(dev, ep->phys[0], MII_LPA) : 0;
	int negotiated = mii_lpa & ep->mii.advertising;
	int duplex = (negotiated & 0x0100) || (negotiated & 0x01C0) == 0x0040;

	if (ep->mii.force_media)
		return;
	if (mii_lpa == 0xffff)		/* Bogus read */
		return;
	if (ep->mii.full_duplex != duplex) {
		ep->mii.full_duplex = duplex;
		printk(KERN_INFO "%s: Setting %s-duplex based on MII #%d link"
			   " partner capability of %4.4x.\n", dev->name,
			   ep->mii.full_duplex ? "full" : "half", ep->phys[0], mii_lpa);
		outl(ep->mii.full_duplex ? 0x7F : 0x79, ioaddr + TxCtrl);
	}
}

static void epic_timer(unsigned long data)
{
	struct net_device *dev = (struct net_device *)data;
	struct epic_private *ep = dev->priv;
	long ioaddr = dev->base_addr;
	int next_tick = 5*HZ;

	if (debug > 3) {
		printk(KERN_DEBUG "%s: Media monitor tick, Tx status %8.8x.\n",
			   dev->name, (int)inl(ioaddr + TxSTAT));
		printk(KERN_DEBUG "%s: Other registers are IntMask %4.4x "
			   "IntStatus %4.4x RxStatus %4.4x.\n",
			   dev->name, (int)inl(ioaddr + INTMASK),
			   (int)inl(ioaddr + INTSTAT), (int)inl(ioaddr + RxSTAT));
	}

	check_media(dev);

	ep->timer.expires = jiffies + next_tick;
	add_timer(&ep->timer);
}

static void epic_tx_timeout(struct net_device *dev)
{
	struct epic_private *ep = dev->priv;
	long ioaddr = dev->base_addr;

	if (debug > 0) {
		printk(KERN_WARNING "%s: Transmit timeout using MII device, "
			   "Tx status %4.4x.\n",
			   dev->name, (int)inw(ioaddr + TxSTAT));
		if (debug > 1) {
			printk(KERN_DEBUG "%s: Tx indices: dirty_tx %d, cur_tx %d.\n",
				   dev->name, ep->dirty_tx, ep->cur_tx);
		}
	}
	if (inw(ioaddr + TxSTAT) & 0x10) {		/* Tx FIFO underflow. */
		ep->stats.tx_fifo_errors++;
		outl(RestartTx, ioaddr + COMMAND);
	} else {
		epic_restart(dev);
		outl(TxQueued, dev->base_addr + COMMAND);
	}

	dev->trans_start = jiffies;
	ep->stats.tx_errors++;
	if (!ep->tx_full)
		netif_wake_queue(dev);
}

/* Initialize the Rx and Tx rings, along with various 'dev' bits. */
static void epic_init_ring(struct net_device *dev)
{
	struct epic_private *ep = dev->priv;
	int i;

	ep->tx_full = 0;
	ep->dirty_tx = ep->cur_tx = 0;
	ep->cur_rx = ep->dirty_rx = 0;
	ep->rx_buf_sz = (dev->mtu <= 1500 ? PKT_BUF_SZ : dev->mtu + 32);

	/* Initialize all Rx descriptors. */
	for (i = 0; i < RX_RING_SIZE; i++) {
		ep->rx_ring[i].rxstatus = 0;
		ep->rx_ring[i].buflength = cpu_to_le32(ep->rx_buf_sz);
		ep->rx_ring[i].next = ep->rx_ring_dma + 
				      (i+1)*sizeof(struct epic_rx_desc);
		ep->rx_skbuff[i] = NULL;
	}
	/* Mark the last entry as wrapping the ring. */
	ep->rx_ring[i-1].next = ep->rx_ring_dma;

	/* Fill in the Rx buffers.  Handle allocation failure gracefully. */
	for (i = 0; i < RX_RING_SIZE; i++) {
		struct sk_buff *skb = dev_alloc_skb(ep->rx_buf_sz);
		ep->rx_skbuff[i] = skb;
		if (skb == NULL)
			break;
		skb->dev = dev;			/* Mark as being used by this device. */
		skb_reserve(skb, 2);	/* 16 byte align the IP header. */
		ep->rx_ring[i].bufaddr = pci_map_single(ep->pci_dev, 
			skb->tail, ep->rx_buf_sz, PCI_DMA_FROMDEVICE);
		ep->rx_ring[i].rxstatus = cpu_to_le32(DescOwn);
	}
	ep->dirty_rx = (unsigned int)(i - RX_RING_SIZE);

	/* The Tx buffer descriptor is filled in as needed, but we
	   do need to clear the ownership bit. */
	for (i = 0; i < TX_RING_SIZE; i++) {
		ep->tx_skbuff[i] = NULL;
		ep->tx_ring[i].txstatus = 0x0000;
		ep->tx_ring[i].next = ep->tx_ring_dma + 
			(i+1)*sizeof(struct epic_tx_desc);
	}
	ep->tx_ring[i-1].next = ep->tx_ring_dma;
	return;
}

static int epic_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct epic_private *ep = dev->priv;
	int entry, free_count;
	u32 ctrl_word;
	unsigned long flags;
	
	if (skb->len < ETH_ZLEN) {
		skb = skb_padto(skb, ETH_ZLEN);
		if (skb == NULL)
			return 0;
	}

	/* Caution: the write order is important here, set the field with the
	   "ownership" bit last. */

	/* Calculate the next Tx descriptor entry. */
	spin_lock_irqsave(&ep->lock, flags);
	free_count = ep->cur_tx - ep->dirty_tx;
	entry = ep->cur_tx % TX_RING_SIZE;

	ep->tx_skbuff[entry] = skb;
	ep->tx_ring[entry].bufaddr = pci_map_single(ep->pci_dev, skb->data, 
		 			            skb->len, PCI_DMA_TODEVICE);
	if (free_count < TX_QUEUE_LEN/2) {/* Typical path */
		ctrl_word = cpu_to_le32(0x100000); /* No interrupt */
	} else if (free_count == TX_QUEUE_LEN/2) {
		ctrl_word = cpu_to_le32(0x140000); /* Tx-done intr. */
	} else if (free_count < TX_QUEUE_LEN - 1) {
		ctrl_word = cpu_to_le32(0x100000); /* No Tx-done intr. */
	} else {
		/* Leave room for an additional entry. */
		ctrl_word = cpu_to_le32(0x140000); /* Tx-done intr. */
		ep->tx_full = 1;
	}
	ep->tx_ring[entry].buflength = ctrl_word | cpu_to_le32(skb->len);
	ep->tx_ring[entry].txstatus =
		((skb->len >= ETH_ZLEN ? skb->len : ETH_ZLEN) << 16)
		| cpu_to_le32(DescOwn);

	ep->cur_tx++;
	if (ep->tx_full)
		netif_stop_queue(dev);

	spin_unlock_irqrestore(&ep->lock, flags);
	/* Trigger an immediate transmit demand. */
	outl(TxQueued, dev->base_addr + COMMAND);

	dev->trans_start = jiffies;
	if (debug > 4)
		printk(KERN_DEBUG "%s: Queued Tx packet size %d to slot %d, "
			   "flag %2.2x Tx status %8.8x.\n",
			   dev->name, (int)skb->len, entry, ctrl_word,
			   (int)inl(dev->base_addr + TxSTAT));

	return 0;
}

static void epic_tx_error(struct net_device *dev, struct epic_private *ep,
			  int status)
{
	struct net_device_stats *stats = &ep->stats;

#ifndef final_version
	/* There was an major error, log it. */
	if (debug > 1)
		printk(KERN_DEBUG "%s: Transmit error, Tx status %8.8x.\n",
		       dev->name, status);
#endif
	stats->tx_errors++;
	if (status & 0x1050)
		stats->tx_aborted_errors++;
	if (status & 0x0008)
		stats->tx_carrier_errors++;
	if (status & 0x0040)
		stats->tx_window_errors++;
	if (status & 0x0010)
		stats->tx_fifo_errors++;
}

static void epic_tx(struct net_device *dev, struct epic_private *ep)
{
	unsigned int dirty_tx, cur_tx;

	/*
	 * Note: if this lock becomes a problem we can narrow the locked
	 * region at the cost of occasionally grabbing the lock more times.
	 */
	cur_tx = ep->cur_tx;
	for (dirty_tx = ep->dirty_tx; cur_tx - dirty_tx > 0; dirty_tx++) {
		struct sk_buff *skb;
		int entry = dirty_tx % TX_RING_SIZE;
		int txstatus = le32_to_cpu(ep->tx_ring[entry].txstatus);

		if (txstatus & DescOwn)
			break;	/* It still hasn't been Txed */

		if (likely(txstatus & 0x0001)) {
			ep->stats.collisions += (txstatus >> 8) & 15;
			ep->stats.tx_packets++;
			ep->stats.tx_bytes += ep->tx_skbuff[entry]->len;
		} else
			epic_tx_error(dev, ep, txstatus);

		/* Free the original skb. */
		skb = ep->tx_skbuff[entry];
		pci_unmap_single(ep->pci_dev, ep->tx_ring[entry].bufaddr, 
				 skb->len, PCI_DMA_TODEVICE);
		dev_kfree_skb_irq(skb);
		ep->tx_skbuff[entry] = NULL;
	}

#ifndef final_version
	if (cur_tx - dirty_tx > TX_RING_SIZE) {
		printk(KERN_WARNING
		       "%s: Out-of-sync dirty pointer, %d vs. %d, full=%d.\n",
		       dev->name, dirty_tx, cur_tx, ep->tx_full);
		dirty_tx += TX_RING_SIZE;
	}
#endif
	ep->dirty_tx = dirty_tx;
	if (ep->tx_full && cur_tx - dirty_tx < TX_QUEUE_LEN - 4) {
		/* The ring is no longer full, allow new TX entries. */
		ep->tx_full = 0;
		netif_wake_queue(dev);
	}
}

/* The interrupt handler does all of the Rx thread work and cleans up
   after the Tx thread. */
static irqreturn_t epic_interrupt(int irq, void *dev_instance, struct pt_regs *regs)
{
	struct net_device *dev = dev_instance;
	struct epic_private *ep = dev->priv;
	long ioaddr = dev->base_addr;
	unsigned int handled = 0;
	int status;

	status = inl(ioaddr + INTSTAT);
	/* Acknowledge all of the current interrupt sources ASAP. */
	outl(status & EpicNormalEvent, ioaddr + INTSTAT);

	if (debug > 4) {
		printk(KERN_DEBUG "%s: Interrupt, status=%#8.8x new "
				   "intstat=%#8.8x.\n", dev->name, status,
				   (int)inl(ioaddr + INTSTAT));
	}

	if ((status & IntrSummary) == 0)
		goto out;

	handled = 1;

	if ((status & EpicNapiEvent) && !ep->reschedule_in_poll) {
		spin_lock(&ep->napi_lock);
		if (netif_rx_schedule_prep(dev)) {
			epic_napi_irq_off(dev, ep);
			__netif_rx_schedule(dev);
		} else
			ep->reschedule_in_poll++;
		spin_unlock(&ep->napi_lock);
	}
	status &= ~EpicNapiEvent;

	/* Check uncommon events all at once. */
	if (status & (CntFull | TxUnderrun | PCIBusErr170 | PCIBusErr175)) {
		if (status == EpicRemoved)
			goto out;

		/* Always update the error counts to avoid overhead later. */
		ep->stats.rx_missed_errors += inb(ioaddr + MPCNT);
		ep->stats.rx_frame_errors += inb(ioaddr + ALICNT);
		ep->stats.rx_crc_errors += inb(ioaddr + CRCCNT);

		if (status & TxUnderrun) { /* Tx FIFO underflow. */
			ep->stats.tx_fifo_errors++;
			outl(ep->tx_threshold += 128, ioaddr + TxThresh);
			/* Restart the transmit process. */
			outl(RestartTx, ioaddr + COMMAND);
		}
		if (status & PCIBusErr170) {
			printk(KERN_ERR "%s: PCI Bus Error! status %4.4x.\n",
					 dev->name, status);
			epic_pause(dev);
			epic_restart(dev);
		}
		/* Clear all error sources. */
		outl(status & 0x7f18, ioaddr + INTSTAT);
	}

out:
	if (debug > 3) {
		printk(KERN_DEBUG "%s: exit interrupt, intr_status=%#4.4x.\n",
				   dev->name, status);
	}

	return IRQ_RETVAL(handled);
}

static int epic_rx(struct net_device *dev, int budget)
{
	struct epic_private *ep = dev->priv;
	int entry = ep->cur_rx % RX_RING_SIZE;
	int rx_work_limit = ep->dirty_rx + RX_RING_SIZE - ep->cur_rx;
	int work_done = 0;

	if (debug > 4)
		printk(KERN_DEBUG " In epic_rx(), entry %d %8.8x.\n", entry,
			   ep->rx_ring[entry].rxstatus);

	if (rx_work_limit > budget)
		rx_work_limit = budget;

	/* If we own the next entry, it's a new packet. Send it up. */
	while ((ep->rx_ring[entry].rxstatus & cpu_to_le32(DescOwn)) == 0) {
		int status = le32_to_cpu(ep->rx_ring[entry].rxstatus);

		if (debug > 4)
			printk(KERN_DEBUG "  epic_rx() status was %8.8x.\n", status);
		if (--rx_work_limit < 0)
			break;
		if (status & 0x2006) {
			if (debug > 2)
				printk(KERN_DEBUG "%s: epic_rx() error status was %8.8x.\n",
					   dev->name, status);
			if (status & 0x2000) {
				printk(KERN_WARNING "%s: Oversized Ethernet frame spanned "
					   "multiple buffers, status %4.4x!\n", dev->name, status);
				ep->stats.rx_length_errors++;
			} else if (status & 0x0006)
				/* Rx Frame errors are counted in hardware. */
				ep->stats.rx_errors++;
		} else {
			/* Malloc up new buffer, compatible with net-2e. */
			/* Omit the four octet CRC from the length. */
			short pkt_len = (status >> 16) - 4;
			struct sk_buff *skb;

			if (pkt_len > PKT_BUF_SZ - 4) {
				printk(KERN_ERR "%s: Oversized Ethernet frame, status %x "
					   "%d bytes.\n",
					   dev->name, status, pkt_len);
				pkt_len = 1514;
			}