Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 9ac98284 authored by Jesse Brandeburg's avatar Jesse Brandeburg Committed by Jeff Garzik
Browse files

e1000: add dynamic generic MSI interrupt routine 



Add a generic MSI interrupt routine that is IO read-free, speeding up
MSI interrupt handling.

Signed-off-by: default avatarJesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: default avatarAuke Kok <auke-jan.h.kok@intel.com>
parent 04fedbfb

drivers/net/e1000/e1000_main.c

+88 −2
Original line number Diff line number Diff line
@@ -157,6 +157,9 @@ static struct net_device_stats * e1000_get_stats(struct net_device *netdev); 
static int e1000_change_mtu(struct net_device *netdev, int new_mtu);

static int e1000_set_mac(struct net_device *netdev, void *p);

static irqreturn_t e1000_intr(int irq, void *data);

#ifdef CONFIG_PCI_MSI

static irqreturn_t e1000_intr_msi(int irq, void *data);

#endif

static boolean_t e1000_clean_tx_irq(struct e1000_adapter *adapter,

                                    struct e1000_tx_ring *tx_ring);

#ifdef CONFIG_E1000_NAPI
@@ -288,7 +291,7 @@ static int e1000_request_irq(struct e1000_adapter *adapter) 


	flags = IRQF_SHARED;

#ifdef CONFIG_PCI_MSI

	if (adapter->hw.mac_type > e1000_82547_rev_2) {

	if (adapter->hw.mac_type >= e1000_82571) {

		adapter->have_msi = TRUE;

		if ((err = pci_enable_msi(adapter->pdev))) {

			DPRINTK(PROBE, ERR,
@@ -296,8 +299,14 @@ static int e1000_request_irq(struct e1000_adapter *adapter) 
			adapter->have_msi = FALSE;

		}

	}

	if (adapter->have_msi)

	if (adapter->have_msi) {

		flags &= ~IRQF_SHARED;

		err = request_irq(adapter->pdev->irq, &e1000_intr_msi, flags,

		                  netdev->name, netdev);

		if (err)

			DPRINTK(PROBE, ERR,

			       "Unable to allocate interrupt Error: %d\n", err);

	} else

#endif

	if ((err = request_irq(adapter->pdev->irq, &e1000_intr, flags,

	                       netdev->name, netdev)))
@@ -3466,6 +3475,83 @@ e1000_update_stats(struct e1000_adapter *adapter) 


	spin_unlock_irqrestore(&adapter->stats_lock, flags);

}

#ifdef CONFIG_PCI_MSI



/**

 * e1000_intr_msi - Interrupt Handler

 * @irq: interrupt number

 * @data: pointer to a network interface device structure

 **/



static

irqreturn_t e1000_intr_msi(int irq, void *data)

{

	struct net_device *netdev = data;

	struct e1000_adapter *adapter = netdev_priv(netdev);

	struct e1000_hw *hw = &adapter->hw;

#ifndef CONFIG_E1000_NAPI

	int i;

#endif



	/* this code avoids the read of ICR but has to get 1000 interrupts

	 * at every link change event before it will notice the change */

	if (++adapter->detect_link >= 1000) {

		uint32_t icr = E1000_READ_REG(hw, ICR);

#ifdef CONFIG_E1000_NAPI

		/* read ICR disables interrupts using IAM, so keep up with our

		 * enable/disable accounting */

		atomic_inc(&adapter->irq_sem);

#endif

		adapter->detect_link = 0;

		if ((icr & (E1000_ICR_RXSEQ | E1000_ICR_LSC)) &&

		    (icr & E1000_ICR_INT_ASSERTED)) {

			hw->get_link_status = 1;

			/* 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->hw.mac_type == e1000_80003es2lan)) {

				/* disable receives */

				uint32_t rctl = E1000_READ_REG(hw, RCTL);

				E1000_WRITE_REG(hw, RCTL, rctl & ~E1000_RCTL_EN);

			}

			/* guard against interrupt when we're going down */

			if (!test_bit(__E1000_DOWN, &adapter->flags))

				mod_timer(&adapter->watchdog_timer,

				          jiffies + 1);

		}

	} else {

		E1000_WRITE_REG(hw, ICR, (0xffffffff & ~(E1000_ICR_RXSEQ |

		                                         E1000_ICR_LSC)));

		/* bummer we have to flush here, but things break otherwise as

		 * some event appears to be lost or delayed and throughput

		 * drops.  In almost all tests this flush is un-necessary */

		E1000_WRITE_FLUSH(hw);

#ifdef CONFIG_E1000_NAPI

		/* Interrupt Auto-Mask (IAM)...upon writing ICR, interrupts are

		 * masked.  No need for the IMC write, but it does mean we

		 * should account for it ASAP. */

		atomic_inc(&adapter->irq_sem);

#endif

	}



#ifdef CONFIG_E1000_NAPI

	if (likely(netif_rx_schedule_prep(netdev)))

		__netif_rx_schedule(netdev);

	else

		e1000_irq_enable(adapter);

#else

	for (i = 0; i < E1000_MAX_INTR; i++)

		if (unlikely(!adapter->clean_rx(adapter, adapter->rx_ring) &

		   !e1000_clean_tx_irq(adapter, adapter->tx_ring)))

			break;

#endif



	return IRQ_HANDLED;

}

#endif



/**

 * e1000_intr - Interrupt Handler