netdev.c

Intel 82546系列lan driver源码

	if (likely(adapter->itr_setting & 3))
		e1000_set_itr(adapter);
#endif /* CONFIG_E1000E_NAPI */

	return IRQ_HANDLED;
}

/**
 * e1000_intr - Interrupt Handler
 * @irq: interrupt number
 * @data: pointer to a network interface device structure
 **/
static irqreturn_t e1000_intr(int irq, void *data)
{
	struct net_device *netdev = data;
	struct e1000_adapter *adapter = netdev_priv(netdev);
	struct e1000_hw *hw = &adapter->hw;
#ifndef CONFIG_E1000E_NAPI
	int i;
	int rx_cleaned, tx_cleaned_complete;
#endif
	u32 rctl, icr = er32(ICR);

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

#ifdef CONFIG_E1000E_NAPI
	/*
	 * IMS will not auto-mask if INT_ASSERTED is not set, and if it is
	 * not set, then the adapter didn't send an interrupt
	 */
	if (!(icr & E1000_ICR_INT_ASSERTED))
		return IRQ_NONE;

#endif /* CONFIG_E1000E_NAPI */
	/*
	 * Interrupt Auto-Mask...upon reading ICR,
	 * interrupts are masked.  No need for the
	 * IMC write
	 */

	if (icr & (E1000_ICR_RXSEQ | E1000_ICR_LSC)) {
		hw->mac.get_link_status = 1;
		/*
		 * ICH8 workaround-- Call gig speed drop workaround on cable
		 * disconnect (LSC) before accessing any PHY registers
		 */
		if ((adapter->flags & FLAG_LSC_GIG_SPEED_DROP) &&
		    (!(er32(STATUS) & E1000_STATUS_LU)))
			schedule_work(&adapter->downshift_task);

		/*
		 * 80003ES2LAN workaround--
		 * For packet buffer work-around on link down event;
		 * disable receives here in the ISR and
		 * reset adapter in watchdog
		 */
		if (netif_carrier_ok(netdev) &&
		    (adapter->flags & FLAG_RX_NEEDS_RESTART)) {
			/* disable receives */
			rctl = er32(RCTL);
			ew32(RCTL, rctl & ~E1000_RCTL_EN);
			adapter->flags |= FLAG_RX_RESTART_NOW;
		}
		/* guard against interrupt when we're going down */
		if (!test_bit(__E1000_DOWN, &adapter->state))
			mod_timer(&adapter->watchdog_timer, jiffies + 1);
	}

#ifdef CONFIG_E1000E_NAPI
	if (netif_rx_schedule_prep(netdev, &adapter->napi)) {
		adapter->total_tx_bytes = 0;
		adapter->total_tx_packets = 0;
		adapter->total_rx_bytes = 0;
		adapter->total_rx_packets = 0;
		__netif_rx_schedule(netdev, &adapter->napi);
	}
#else
	adapter->total_tx_bytes = 0;
	adapter->total_rx_bytes = 0;
	adapter->total_tx_packets = 0;
	adapter->total_rx_packets = 0;

	for (i = 0; i < E1000_MAX_INTR; i++) {
		rx_cleaned = adapter->clean_rx(adapter);
		tx_cleaned_complete = e1000_clean_tx_irq(adapter);
		if (!rx_cleaned && tx_cleaned_complete)
			break;
	}

	if (likely(adapter->itr_setting & 3))
		e1000_set_itr(adapter);
#endif /* CONFIG_E1000E_NAPI */

	return IRQ_HANDLED;
}

#ifdef CONFIG_E1000E_MSIX
static irqreturn_t e1000_msix_other(int irq, void *data)
{
	struct net_device *netdev = data;
	struct e1000_adapter *adapter = netdev_priv(netdev);
	struct e1000_hw *hw = &adapter->hw;
	u32 icr = er32(ICR);

	if (!(icr & E1000_ICR_INT_ASSERTED)) {
		ew32(IMS, E1000_IMS_OTHER);
		return IRQ_NONE;
	}

	if (icr & adapter->eiac_mask)
		ew32(ICS, (icr & adapter->eiac_mask));

	if (icr & E1000_ICR_OTHER) {
		if (!(icr & E1000_ICR_LSC))
			goto no_link_interrupt;
		hw->mac.get_link_status = 1;
		/* guard against interrupt when we're going down */
		if (!test_bit(__E1000_DOWN, &adapter->state))
			mod_timer(&adapter->watchdog_timer, jiffies + 1);
	}

no_link_interrupt:
	ew32(IMS, E1000_IMS_LSC | E1000_IMS_OTHER);

	return IRQ_HANDLED;
}


#ifdef CONFIG_E1000E_SEPARATE_TX_HANDLER
static irqreturn_t e1000_intr_msix_tx(int irq, void *data)
{
	struct net_device *netdev = data;
	struct e1000_adapter *adapter = netdev_priv(netdev);
	struct e1000_hw *hw = &adapter->hw;
	struct e1000_ring *tx_ring = adapter->tx_ring;


	adapter->total_tx_bytes = 0;
	adapter->total_tx_packets = 0;

	if (!e1000_clean_tx_irq(adapter))
		/* Ring was not completely cleaned, so fire another interrupt */
		ew32(ICS, tx_ring->ims_val);

	return IRQ_HANDLED;
}

#endif  /* CONFIG_E1000E_SEPARATE_TX_HANDLER */
static irqreturn_t e1000_intr_msix_rx(int irq, void *data)
{
	struct net_device *netdev = data;
	struct e1000_adapter *adapter = netdev_priv(netdev);
#ifndef CONFIG_E1000E_NAPI
	int i;
	struct e1000_hw *hw = &adapter->hw;
#endif

	/* Write the ITR value calculated at the end of the
	 * previous interrupt.
	 */
	if (adapter->rx_ring->set_itr) {
		writel(1000000000 / (adapter->rx_ring->itr_val * 256),
		       adapter->hw.hw_addr + adapter->rx_ring->itr_register);
		adapter->rx_ring->set_itr = 0;
	}

#ifdef CONFIG_E1000E_NAPI
	if (netif_rx_schedule_prep(netdev, &adapter->napi)) {
		adapter->total_rx_bytes = 0;
		adapter->total_rx_packets = 0;
#ifndef CONFIG_E1000E_SEPARATE_TX_HANDLER
		adapter->total_tx_bytes = 0;
		adapter->total_tx_packets = 0;
#endif /* CONFIG_E1000E_SEPARATE_TX_HANDLER */
		__netif_rx_schedule(netdev, &adapter->napi);
	}
#else
	adapter->total_rx_bytes = 0;
	adapter->total_rx_packets = 0;
#ifndef CONFIG_E1000E_SEPARATE_TX_HANDLER
	adapter->total_tx_bytes = 0;
	adapter->total_tx_packets = 0;
#endif

	for (i = 0; i < E1000_MAX_INTR; i++) {
		int rx_cleaned = adapter->clean_rx(adapter);
#ifndef CONFIG_E1000E_SEPARATE_TX_HANDLER
		int tx_cleaned_complete = e1000_clean_tx_irq(adapter);
		if (!rx_cleaned && tx_cleaned_complete)
#else
		if (!rx_cleaned)
#endif
			goto out;
	}
	/* If we got here, the ring was not completely cleaned,
	 * so fire another interrupt.
	 */
	ew32(ICS, adapter->rx_ring->ims_val);

out:
#endif /* CONFIG_E1000E_NAPI */
	return IRQ_HANDLED;
}

/**
 * e1000_configure_msix - Configure MSI-X hardware
 *
 * e1000_configure_msix sets up the hardware to properly
 * generate MSI-X interrupts.
 **/
static void e1000_configure_msix(struct e1000_adapter *adapter)
{
	struct e1000_hw *hw = &adapter->hw;
	struct e1000_ring *rx_ring = adapter->rx_ring;
	struct e1000_ring *tx_ring = adapter->tx_ring;
	int vector = 0;
	u32 ctrl_ext, ivar = 0;

	adapter->eiac_mask = 0;

	/* Workaround issue with spurious interrupts on 82574 in MSI-X mode */
	if (hw->mac.type == e1000_82574) {
		u32 rfctl = er32(RFCTL);
		rfctl |= E1000_RFCTL_ACK_DIS;
		ew32(RFCTL, rfctl);
	}

#define E1000_IVAR_INT_ALLOC_VALID	0x8
	/* Configure Rx vector */
	rx_ring->ims_val = E1000_IMS_RXQ0;
	adapter->eiac_mask |= rx_ring->ims_val;
	if (rx_ring->itr_val)
		writel(1000000000 / (rx_ring->itr_val * 256),
		       hw->hw_addr + rx_ring->itr_register);
	else
		writel(1, hw->hw_addr + rx_ring->itr_register);
	ivar = E1000_IVAR_INT_ALLOC_VALID | vector;

	/* Configure Tx vector */
	tx_ring->ims_val = E1000_IMS_TXQ0;
#ifdef CONFIG_E1000E_SEPARATE_TX_HANDLER
	vector++;
	if (tx_ring->itr_val)
		writel(1000000000 / (tx_ring->itr_val * 256),
		       hw->hw_addr + tx_ring->itr_register);
	else
		writel(1, hw->hw_addr + tx_ring->itr_register);
#else
	rx_ring->ims_val |= tx_ring->ims_val;
#endif
	adapter->eiac_mask |= tx_ring->ims_val;
	ivar |= ((E1000_IVAR_INT_ALLOC_VALID | vector) << 8);

	/* set vector for Other Causes, e.g. link changes */
	vector++;
	ivar |= ((E1000_IVAR_INT_ALLOC_VALID | vector) << 16);
	if (rx_ring->itr_val)
		writel(1000000000 / (rx_ring->itr_val * 256),
		       hw->hw_addr + E1000_EITR_82574(vector));
	else
		writel(1, hw->hw_addr + E1000_EITR_82574(vector));

	/* Cause Tx interrupts on every write back */
	ivar |= (1 << 31);

	ew32(IVAR, ivar);

	/* enable MSI-X PBA support */
	ctrl_ext = er32(CTRL_EXT);
	ctrl_ext |= E1000_CTRL_EXT_PBA_CLR;

	/* Auto-Mask Other interrupts upon ICR read */
	ew32(IAM, ~E1000_EIAC_MASK_82574 | E1000_IMS_OTHER);
	ctrl_ext |= E1000_CTRL_EXT_EIAME;
	ew32(CTRL_EXT, ctrl_ext);
	e1e_flush();
}

void e1000e_reset_interrupt_capability(struct e1000_adapter *adapter)
{
	if (adapter->msix_entries) {
		pci_disable_msix(adapter->pdev);
		kfree(adapter->msix_entries);
		adapter->msix_entries = NULL;
	} else if (adapter->flags & FLAG_MSI_ENABLED) {
		pci_disable_msi(adapter->pdev);
		adapter->flags &= ~FLAG_MSI_ENABLED;
	}

	return;
}

/**
 * e1000e_set_interrupt_capability - set MSI or MSI-X if supported
 *
 * Attempt to configure interrupts using the best available
 * capabilities of the hardware and kernel.
 **/
void e1000e_set_interrupt_capability(struct e1000_adapter *adapter)
{
	int err;
	int numvecs, i;


	switch (adapter->int_mode) {
	case E1000E_INT_MODE_MSIX:
		if (adapter->flags & FLAG_HAS_MSIX) {
#ifdef CONFIG_E1000E_SEPARATE_TX_HANDLER
			numvecs = 3; /* RxQ0, TxQ0 and other */
#else
			numvecs = 2; /* RxQ0/TxQ0 and other */
#endif
			adapter->msix_entries = kcalloc(numvecs,
						      sizeof(struct msix_entry),
						      GFP_KERNEL);
			if (adapter->msix_entries) {
				for (i = 0; i < numvecs; i++)
					adapter->msix_entries[i].entry = i;

				err = pci_enable_msix(adapter->pdev,
						      adapter->msix_entries,
						      numvecs);
				if (err == 0)
					return;
			}
			/* MSI-X failed, so fall through and try MSI */
			e_err("Failed to initialize MSI-X interrupts.  "
			      "Falling back to MSI interrupts.\n");
			e1000e_reset_interrupt_capability(adapter);
		}
		adapter->int_mode = E1000E_INT_MODE_MSI;
		/* Fall through */
	case E1000E_INT_MODE_MSI:
		if (!pci_enable_msi(adapter->pdev)) {
			adapter->flags |= FLAG_MSI_ENABLED;
		} else {
			adapter->int_mode = E1000E_INT_MODE_LEGACY;
			e_err("Failed to initialize MSI interrupts.  Falling "
			      "back to legacy interrupts.\n");
		}
		/* Fall through */
	case E1000E_INT_MODE_LEGACY:
		/* Don't do anything; this is the system default */
		break;
	}

	return;
}

/**
 * e1000_request_msix - Initialize MSI-X interrupts
 *
 * e1000_request_msix allocates MSI-X vectors and requests interrupts from the
 * kernel.
 **/
static int e1000_request_msix(struct e1000_adapter *adapter)
{
	struct net_device *netdev = adapter->netdev;
	int err = 0, vector = 0;

	if (strlen(netdev->name) < (IFNAMSIZ - 5))
#ifdef CONFIG_E1000E_SEPARATE_TX_HANDLER
		sprintf(adapter->rx_ring->name, "%s-rx-0", netdev->name);
#else
		sprintf(adapter->rx_ring->name, "%s-Q0", netdev->name);
#endif
	else
		memcpy(adapter->rx_ring->name, netdev->name, IFNAMSIZ);
	err = request_irq(adapter->msix_entries[vector].vector,
			  &e1000_intr_msix_rx, 0, adapter->rx_ring->name,
			  netdev);
	if (err)
		goto out;
	adapter->rx_ring->itr_register = E1000_EITR_82574(vector);
	adapter->rx_ring->itr_val = adapter->itr;
	vector++;

#ifdef CONFIG_E1000E_SEPARATE_TX_HANDLER
	if (strlen(netdev->name) < (IFNAMSIZ - 5))
		sprintf(adapter->tx_ring->name, "%s-tx-0", netdev->name);
	else
		memcpy(adapter->tx_ring->name, netdev->name, IFNAMSIZ);
	err = request_irq(adapter->msix_entries[vector].vector,
			  &e1000_intr_msix_tx, 0, adapter->tx_ring->name,
			  netdev);
	if (err)
		goto out;
	adapter->tx_ring->itr_register = E1000_EITR_82574(vector);
	adapter->tx_ring->itr_val = adapter->itr;
	vector++;

#endif /* CONFIG_E1000E_SEPARATE_TX_HANDLER */
	err = request_irq(adapter->msix_entries[vector].vector,
			  &e1000_msix_other, 0, netdev->name, netdev);
	if (err)
		goto out;

	e1000_configure_msix(adapter);
	return 0;
out:
	return err;
}

#endif /* CONFIG_E1000E_MSIX */
/**
 * e1000_request_irq - initialize interrupts
 *
 * Attempts to configure interrupts using the best available
 * capabilities of the hardware and kernel.
 **/
static int e1000_request_irq(struct e1000_adapter *adapter)
{
	struct net_device *netdev = adapter->netdev;
#ifndef CONFIG_E1000E_MSIX
	int irq_flags = IRQF_SHARED;
#endif
	int err;

#ifdef CONFIG_E1000E_MSIX
	if (adapter->msix_entries) {
		err = e1000_request_msix(adapter);
		if (!err)
			return err;
		/* fall back to MSI */
		e1000e_reset_interrupt_capability(adapter);
		adapter->int_mode = E1000E_INT_MODE_MSI;
		e1000e_set_interrupt_capability(adapter);
	}
	if (adapter->flags & FLAG_MSI_ENABLED) {
		err = request_irq(adapter->pdev->irq, &e1000_intr_msi, 0,
				  netdev->name, netdev);
		if (!err)
			return err;

		/* fall back to legacy interrupt */
		e1000e_reset_interrupt_capability(adapter);
		adapter->int_mode = E1000E_INT_MODE_LEGACY;
	}

	err = request_irq(adapter->pdev->irq, &e1000_intr, IRQF_SHARED,
			  netdev->name, netdev);
	if (err)
		e_err("Unable to allocate interrupt, Error: %d\n", err);
#else
	if (!(adapter->flags & FLAG_MSI_TEST_FAILED)) {
		err = pci_enable_msi(adapter->pdev);
		if (!err) {
			adapter->flags |= FLAG_MSI_ENABLED;
			irq_flags = 0;
		}
	}

	err = request_irq(adapter->pdev->irq,
			  ((adapter->flags & FLAG_MSI_ENABLED) ?
				&e1000_intr_msi : &e1000_intr),
			  irq_flags, netdev->name, netdev);
	if (err) {
		if (adapter->flags & FLAG_MSI_ENABLED) {
			pci_disable_msi(adapter->pdev);
			adapter->flags &= ~FLAG_MSI_ENABLED;
		}
		e_err("Unable to allocate interrupt, Error: %d\n", err);
	}
#endif /* CONFIG_E1000E_MSIX */

	return err;
}

static void e1000_free_irq(struct e1000_adapter *adapter)
{
	struct net_device *netdev = adapter->netdev;

#ifdef CONFIG_E1000E_MSIX
	if (adapter->msix_entries) {
		int vector = 0;

		free_irq(adapter->msix_entries[vector].vector, netdev);
		vector++;

#ifdef CONFIG_E1000E_SEPARATE_TX_HANDLER
		free_irq(adapter->msix_entries[vector].vector, netdev);
		vector++;