e1000_main.c

一个2.4.21版本的嵌入式linux内核

/**
 * e1000_intr - Interrupt Handler
 * @irq: interrupt number
 * @data: pointer to a network interface device structure
 * @pt_regs: CPU registers structure
 **/

static void
e1000_intr(int irq, void *data, struct pt_regs *regs)
{
	struct net_device *netdev = data;
	struct e1000_adapter *adapter = netdev->priv;
	uint32_t icr = E1000_READ_REG(&adapter->hw, ICR);
	int i;

	if(!icr)
		return;  /* Not our interrupt */

	if(icr & (E1000_ICR_RXSEQ | E1000_ICR_LSC)) {
		adapter->hw.get_link_status = 1;
		mod_timer(&adapter->watchdog_timer, jiffies);
	}

	for(i = 0; i < E1000_MAX_INTR; i++)
		if(!e1000_clean_rx_irq(adapter) &&
		   !e1000_clean_tx_irq(adapter))
			break;

}

/**
 * e1000_clean_tx_irq - Reclaim resources after transmit completes
 * @adapter: board private structure
 **/

static boolean_t
e1000_clean_tx_irq(struct e1000_adapter *adapter)
{
	struct e1000_desc_ring *tx_ring = &adapter->tx_ring;
	struct net_device *netdev = adapter->netdev;
	struct pci_dev *pdev = adapter->pdev;
	struct e1000_tx_desc *tx_desc;
	int i, cleaned = FALSE;

	i = tx_ring->next_to_clean;
	tx_desc = E1000_TX_DESC(*tx_ring, i);

	while(tx_desc->upper.data & cpu_to_le32(E1000_TXD_STAT_DD)) {

		cleaned = TRUE;

		if(tx_ring->buffer_info[i].dma) {

			pci_unmap_page(pdev,
			               tx_ring->buffer_info[i].dma,
			               tx_ring->buffer_info[i].length,
			               PCI_DMA_TODEVICE);

			tx_ring->buffer_info[i].dma = 0;
		}

		if(tx_ring->buffer_info[i].skb) {

			dev_kfree_skb_any(tx_ring->buffer_info[i].skb);

			tx_ring->buffer_info[i].skb = NULL;
		}

		tx_desc->buffer_addr = 0;
		tx_desc->lower.data = 0;
		tx_desc->upper.data = 0;

		if(++i == tx_ring->count) i = 0;
		tx_desc = E1000_TX_DESC(*tx_ring, i);
	}

	tx_ring->next_to_clean = i;

	if(cleaned && netif_queue_stopped(netdev) && netif_carrier_ok(netdev))
		netif_wake_queue(netdev);

	return cleaned;
}

/**
 * e1000_clean_rx_irq - Send received data up the network stack,
 * @adapter: board private structure
 **/

static boolean_t
e1000_clean_rx_irq(struct e1000_adapter *adapter)
{
	struct e1000_desc_ring *rx_ring = &adapter->rx_ring;
	struct net_device *netdev = adapter->netdev;
	struct pci_dev *pdev = adapter->pdev;
	struct e1000_rx_desc *rx_desc;
	struct sk_buff *skb;
	unsigned long flags;
	uint32_t length;
	uint8_t last_byte;
	int i, cleaned = FALSE;

	i = rx_ring->next_to_clean;
	rx_desc = E1000_RX_DESC(*rx_ring, i);

	while(rx_desc->status & E1000_RXD_STAT_DD) {

		cleaned = TRUE;

		pci_unmap_single(pdev,
		                 rx_ring->buffer_info[i].dma,
		                 rx_ring->buffer_info[i].length,
		                 PCI_DMA_FROMDEVICE);

		skb = rx_ring->buffer_info[i].skb;
		length = le16_to_cpu(rx_desc->length);

		if(!(rx_desc->status & E1000_RXD_STAT_EOP)) {

			/* All receives must fit into a single buffer */

			E1000_DBG("Receive packet consumed multiple buffers\n");

			dev_kfree_skb_irq(skb);
			rx_desc->status = 0;
			rx_ring->buffer_info[i].skb = NULL;

			if(++i == rx_ring->count) i = 0;

			rx_desc = E1000_RX_DESC(*rx_ring, i);
			continue;
		}

		if(rx_desc->errors & E1000_RXD_ERR_FRAME_ERR_MASK) {

			last_byte = *(skb->data + length - 1);

			if(TBI_ACCEPT(&adapter->hw, rx_desc->status,
			              rx_desc->errors, length, last_byte)) {

				spin_lock_irqsave(&adapter->stats_lock, flags);

				e1000_tbi_adjust_stats(&adapter->hw,
				                       &adapter->stats,
				                       length, skb->data);

				spin_unlock_irqrestore(&adapter->stats_lock,
				                       flags);
				length--;
			} else {

				dev_kfree_skb_irq(skb);
				rx_desc->status = 0;
				rx_ring->buffer_info[i].skb = NULL;

				if(++i == rx_ring->count) i = 0;

				rx_desc = E1000_RX_DESC(*rx_ring, i);
				continue;
			}
		}

		/* Good Receive */
		skb_put(skb, length - ETHERNET_FCS_SIZE);

		/* Receive Checksum Offload */
		e1000_rx_checksum(adapter, rx_desc, skb);

		skb->protocol = eth_type_trans(skb, netdev);
		if(adapter->vlgrp && (rx_desc->status & E1000_RXD_STAT_VP)) {
			vlan_hwaccel_rx(skb, adapter->vlgrp,
				(rx_desc->special & E1000_RXD_SPC_VLAN_MASK));
		} else {
			netif_rx(skb);
		}
		netdev->last_rx = jiffies;

		rx_desc->status = 0;
		rx_ring->buffer_info[i].skb = NULL;

		if(++i == rx_ring->count) i = 0;

		rx_desc = E1000_RX_DESC(*rx_ring, i);
	}

	rx_ring->next_to_clean = i;

	e1000_alloc_rx_buffers(adapter);

	return cleaned;
}

/**
 * e1000_alloc_rx_buffers - Replace used receive buffers
 * @data: address of board private structure
 **/

static void
e1000_alloc_rx_buffers(struct e1000_adapter *adapter)
{
	struct e1000_desc_ring *rx_ring = &adapter->rx_ring;
	struct net_device *netdev = adapter->netdev;
	struct pci_dev *pdev = adapter->pdev;
	struct e1000_rx_desc *rx_desc;
	struct sk_buff *skb;
	int reserve_len = 2;
	int i;

	i = rx_ring->next_to_use;

	while(!rx_ring->buffer_info[i].skb) {
		rx_desc = E1000_RX_DESC(*rx_ring, i);

		skb = dev_alloc_skb(adapter->rx_buffer_len + reserve_len);

		if(!skb) {
			/* Better luck next round */
			break;
		}

		/* Make buffer alignment 2 beyond a 16 byte boundary
		 * this will result in a 16 byte aligned IP header after
		 * the 14 byte MAC header is removed
		 */
		skb_reserve(skb, reserve_len);

		skb->dev = netdev;

		rx_ring->buffer_info[i].skb = skb;
		rx_ring->buffer_info[i].length = adapter->rx_buffer_len;
		rx_ring->buffer_info[i].dma =
			pci_map_single(pdev,
			               skb->data,
			               adapter->rx_buffer_len,
			               PCI_DMA_FROMDEVICE);

		rx_desc->buffer_addr = cpu_to_le64(rx_ring->buffer_info[i].dma);

		if((i & ~(E1000_RX_BUFFER_WRITE - 1)) == i) {
			/* Force memory writes to complete before letting h/w
			 * know there are new descriptors to fetch.  (Only
			 * applicable for weak-ordered memory model archs,
			 * such as IA-64). */
			wmb();

			E1000_WRITE_REG(&adapter->hw, RDT, i);
		}

		if(++i == rx_ring->count) i = 0;
	}

	rx_ring->next_to_use = i;
}

/**
 * e1000_smartspeed - Workaround for SmartSpeed on 82541 and 82547 controllers.
 * @adapter:
 **/

static void
e1000_smartspeed(struct e1000_adapter *adapter)
{
	uint16_t phy_status;
	uint16_t phy_ctrl;

	if((adapter->hw.phy_type != e1000_phy_igp) || !adapter->hw.autoneg ||
	   !(adapter->hw.autoneg_advertised & ADVERTISE_1000_FULL))
		return;

	if(adapter->smartspeed == 0) {
		/* If Master/Slave config fault is asserted twice,
		 * we assume back-to-back */
		e1000_read_phy_reg(&adapter->hw, PHY_1000T_STATUS, &phy_status);
		if(!(phy_status & SR_1000T_MS_CONFIG_FAULT)) return;
		e1000_read_phy_reg(&adapter->hw, PHY_1000T_STATUS, &phy_status);
		if(!(phy_status & SR_1000T_MS_CONFIG_FAULT)) return;
		e1000_read_phy_reg(&adapter->hw, PHY_1000T_CTRL, &phy_ctrl);
		if(phy_ctrl & CR_1000T_MS_ENABLE) {
			phy_ctrl &= ~CR_1000T_MS_ENABLE;
			e1000_write_phy_reg(&adapter->hw, PHY_1000T_CTRL,
					    phy_ctrl);
			adapter->smartspeed++;
			if(!e1000_phy_setup_autoneg(&adapter->hw) &&
			   !e1000_read_phy_reg(&adapter->hw, PHY_CTRL,
				   	       &phy_ctrl)) {
				phy_ctrl |= (MII_CR_AUTO_NEG_EN |
					     MII_CR_RESTART_AUTO_NEG);
				e1000_write_phy_reg(&adapter->hw, PHY_CTRL,
						    phy_ctrl);
			}
		}
		return;
	} else if(adapter->smartspeed == E1000_SMARTSPEED_DOWNSHIFT) {
		/* If still no link, perhaps using 2/3 pair cable */
		e1000_read_phy_reg(&adapter->hw, PHY_1000T_CTRL, &phy_ctrl);
		phy_ctrl |= CR_1000T_MS_ENABLE;
		e1000_write_phy_reg(&adapter->hw, PHY_1000T_CTRL, phy_ctrl);
		if(!e1000_phy_setup_autoneg(&adapter->hw) &&
		   !e1000_read_phy_reg(&adapter->hw, PHY_CTRL, &phy_ctrl)) {
			phy_ctrl |= (MII_CR_AUTO_NEG_EN |
				     MII_CR_RESTART_AUTO_NEG);
			e1000_write_phy_reg(&adapter->hw, PHY_CTRL, phy_ctrl);
		}
	}
	/* Restart process after E1000_SMARTSPEED_MAX iterations */
	if(adapter->smartspeed++ == E1000_SMARTSPEED_MAX)
		adapter->smartspeed = 0;
}

/**
 * e1000_ioctl -
 * @netdev:
 * @ifreq:
 * @cmd:
 **/

static int
e1000_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
{
	switch (cmd) {
	case SIOCGMIIPHY:
	case SIOCGMIIREG:
	case SIOCSMIIREG:
		return e1000_mii_ioctl(netdev, ifr, cmd);
	case SIOCETHTOOL:
		return e1000_ethtool_ioctl(netdev, ifr);
	default:
		return -EOPNOTSUPP;
	}
}

/**
 * e1000_mii_ioctl -
 * @netdev:
 * @ifreq:
 * @cmd:
 **/

static int
e1000_mii_ioctl(struct net_device *netdev, struct ifreq *ifr, int cmd)
{
	struct e1000_adapter *adapter = netdev->priv;
	struct mii_ioctl_data *data = (struct mii_ioctl_data *)&ifr->ifr_data;
	int retval;
	uint16_t mii_reg;
	uint16_t spddplx;

	if(adapter->hw.media_type == e1000_media_type_fiber)
		return -EOPNOTSUPP;

	switch (cmd) {
	case SIOCGMIIPHY:
		data->phy_id = adapter->hw.phy_addr;
		break;
	case SIOCGMIIREG:
		if (!capable(CAP_NET_ADMIN))
			return -EPERM;
		if (e1000_read_phy_reg(&adapter->hw, data->reg_num & 0x1F,
				   &data->val_out))
			return -EIO;
		break;
	case SIOCSMIIREG:
		if (!capable(CAP_NET_ADMIN))
			return -EPERM;
		if (data->reg_num & ~(0x1F))
			return -EFAULT;
		mii_reg = data->val_in;
		if (e1000_write_phy_reg(&adapter->hw, data->reg_num,
					data->val_in))
			return -EIO;
		if (adapter->hw.phy_type == e1000_phy_m88) {
			switch (data->reg_num) {
			case PHY_CTRL:
				if(data->val_in & MII_CR_AUTO_NEG_EN) {
					adapter->hw.autoneg = 1;
					adapter->hw.autoneg_advertised = 0x2F;
				} else {
					if (data->val_in & 0x40)
						spddplx = SPEED_1000;
					else if (data->val_in & 0x2000)
						spddplx = SPEED_100;
					else
						spddplx = SPEED_10;
					spddplx += (data->val_in & 0x100)
						   ? FULL_DUPLEX :
						   HALF_DUPLEX;
					retval = e1000_set_spd_dplx(adapter,
								    spddplx);
					if(retval)
						return retval;
				}
				if(netif_running(adapter->netdev)) {
					e1000_down(adapter);
					e1000_up(adapter);
				} else
					e1000_reset(adapter);
				break;
			case M88E1000_PHY_SPEC_CTRL:
			case M88E1000_EXT_PHY_SPEC_CTRL:
				if (e1000_phy_reset(&adapter->hw))
					return -EIO;
				break;
			}
		}
		break;
	default:
		return -EOPNOTSUPP;
	}
	return E1000_SUCCESS;
}

/**
 * e1000_rx_checksum - Receive Checksum Offload for 82543
 * @adapter: board private structure
 * @rx_desc: receive descriptor
 * @sk_buff: socket buffer with received data
 **/

static inline void
e1000_rx_checksum(struct e1000_adapter *adapter,
                  struct e1000_rx_desc *rx_desc,
                  struct sk_buff *skb)
{
	/* 82543 or newer only */
	if((adapter->hw.mac_type < e1000_82543) ||
	/* Ignore Checksum bit is set */
	(rx_desc->status & E1000_RXD_STAT_IXSM) ||
	/* TCP Checksum has not been calculated */
	(!(rx_desc->status & E1000_RXD_STAT_TCPCS))) {
		skb->ip_summed = CHECKSUM_NONE;
		return;
	}

	/* At this point we know the hardware did the TCP checksum */
	/* now look at the TCP checksum error bit */
	if(rx_desc->errors & E1000_RXD_ERR_TCPE) {
		/* let the stack verify checksum errors */
		skb->ip_summed = CHECKSUM_NONE;
		adapter->hw_csum_err++;
	} else {
	/* TCP checksum is good */
		skb->ip_summed = CHECKSUM_UNNECESSARY;
		adapter->hw_csum_good++;
	}
}

void
e1000_pci_set_mwi(struct e1000_hw *hw)
{
	struct e1000_adapter *adapter = hw->back;

	pci_set_mwi(adapter->pdev);
}

void
e1000_pci_clear_mwi(struct e1000_hw *hw)
{
	struct e1000_adapter *adapter = hw->back;

	pci_clear_mwi(adapter->pdev);
}

void
e1000_read_pci_cfg(struct e1000_hw *hw, uint32_t reg, uint16_t *value)
{
	struct e1000_adapter *adapter = hw->back;

	pci_read_config_word(adapter->pdev, reg, value);
}

void
e1000_write_pci_cfg(struct