netdev.c

Intel 82546系列lan driver源码

#endif
		/* Other Causes interrupt vector */
		free_irq(adapter->msix_entries[vector].vector, netdev);
		return;
	}

#endif /* CONFIG_E1000E_MSIX */
	free_irq(adapter->pdev->irq, netdev);
#ifndef CONFIG_E1000E_MSIX
	if (adapter->flags & FLAG_MSI_ENABLED) {
		pci_disable_msi(adapter->pdev);
		adapter->flags &= ~FLAG_MSI_ENABLED;
	}
#endif
}

/**
 * e1000_irq_disable - Mask off interrupt generation on the NIC
 **/
static void e1000_irq_disable(struct e1000_adapter *adapter)
{
	struct e1000_hw *hw = &adapter->hw;

	ew32(IMC, ~0);
#ifdef CONFIG_E1000E_MSIX
	if (adapter->msix_entries)
		ew32(EIAC_82574, 0);
#endif /* CONFIG_E1000E_MSIX */
	e1e_flush();
	synchronize_irq(adapter->pdev->irq);
}

/**
 * e1000_irq_enable - Enable default interrupt generation settings
 **/
static void e1000_irq_enable(struct e1000_adapter *adapter)
{
	struct e1000_hw *hw = &adapter->hw;

#ifdef CONFIG_E1000E_MSIX
	if (adapter->msix_entries) {
		ew32(EIAC_82574, adapter->eiac_mask & E1000_EIAC_MASK_82574);
		ew32(IMS, adapter->eiac_mask | E1000_IMS_OTHER | E1000_IMS_LSC);
	} else {
		ew32(IMS, IMS_ENABLE_MASK);
	}
#else
	ew32(IMS, IMS_ENABLE_MASK);
#endif /* CONFIG_E1000E_MSIX */
	e1e_flush();
}

/**
 * e1000_get_hw_control - get control of the h/w from f/w
 * @adapter: address of board private structure
 *
 * e1000_get_hw_control sets {CTRL_EXT|SWSM}:DRV_LOAD bit.
 * For ASF and Pass Through versions of f/w this means that
 * the driver is loaded. For AMT version (only with 82573)
 * of the f/w this means that the network i/f is open.
 **/
static void e1000_get_hw_control(struct e1000_adapter *adapter)
{
	struct e1000_hw *hw = &adapter->hw;
	u32 ctrl_ext;
	u32 swsm;

	/* Let firmware know the driver has taken over */
	if (adapter->flags & FLAG_HAS_SWSM_ON_LOAD) {
		swsm = er32(SWSM);
		ew32(SWSM, swsm | E1000_SWSM_DRV_LOAD);
	} else if (adapter->flags & FLAG_HAS_CTRLEXT_ON_LOAD) {
		ctrl_ext = er32(CTRL_EXT);
		ew32(CTRL_EXT, ctrl_ext | E1000_CTRL_EXT_DRV_LOAD);
	}
}

/**
 * e1000_release_hw_control - release control of the h/w to f/w
 * @adapter: address of board private structure
 *
 * e1000_release_hw_control resets {CTRL_EXT|SWSM}:DRV_LOAD bit.
 * For ASF and Pass Through versions of f/w this means that the
 * driver is no longer loaded. For AMT version (only with 82573) i
 * of the f/w this means that the network i/f is closed.
 *
 **/
static void e1000_release_hw_control(struct e1000_adapter *adapter)
{
	struct e1000_hw *hw = &adapter->hw;
	u32 ctrl_ext;
	u32 swsm;

	/* Let firmware taken over control of h/w */
	if (adapter->flags & FLAG_HAS_SWSM_ON_LOAD) {
		swsm = er32(SWSM);
		ew32(SWSM, swsm & ~E1000_SWSM_DRV_LOAD);
	} else if (adapter->flags & FLAG_HAS_CTRLEXT_ON_LOAD) {
		ctrl_ext = er32(CTRL_EXT);
		ew32(CTRL_EXT, ctrl_ext & ~E1000_CTRL_EXT_DRV_LOAD);
	}
}

/**
 * @e1000_alloc_ring - allocate memory for a ring structure
 **/
static int e1000_alloc_ring_dma(struct e1000_adapter *adapter,
				struct e1000_ring *ring)
{
	struct pci_dev *pdev = adapter->pdev;

	ring->desc = dma_alloc_coherent(&pdev->dev, ring->size, &ring->dma,
					GFP_KERNEL);
	if (!ring->desc)
		return -ENOMEM;

	return 0;
}

/**
 * e1000e_setup_tx_resources - allocate Tx resources (Descriptors)
 * @adapter: board private structure
 *
 * Return 0 on success, negative on failure
 **/
int e1000e_setup_tx_resources(struct e1000_adapter *adapter)
{
	struct e1000_ring *tx_ring = adapter->tx_ring;
	int err = -ENOMEM, size;

	size = sizeof(struct e1000_buffer) * tx_ring->count;
	tx_ring->buffer_info = vmalloc(size);
	if (!tx_ring->buffer_info)
		goto err;
	memset(tx_ring->buffer_info, 0, size);

	/* round up to nearest 4K */
	tx_ring->size = tx_ring->count * sizeof(struct e1000_tx_desc);
	tx_ring->size = ALIGN(tx_ring->size, 4096);

	err = e1000_alloc_ring_dma(adapter, tx_ring);
	if (err)
		goto err;

	tx_ring->next_to_use = 0;
	tx_ring->next_to_clean = 0;
	spin_lock_init(&adapter->tx_queue_lock);

	return 0;
err:
	vfree(tx_ring->buffer_info);
	e_err("Unable to allocate memory for the transmit descriptor ring\n");
	return err;
}

/**
 * e1000e_setup_rx_resources - allocate Rx resources (Descriptors)
 * @adapter: board private structure
 *
 * Returns 0 on success, negative on failure
 **/
int e1000e_setup_rx_resources(struct e1000_adapter *adapter)
{
	struct e1000_ring *rx_ring = adapter->rx_ring;
	struct e1000_buffer *buffer_info;
	int i, size, desc_len, err = -ENOMEM;

	size = sizeof(struct e1000_buffer) * rx_ring->count;
	rx_ring->buffer_info = vmalloc(size);
	if (!rx_ring->buffer_info)
		goto err;
	memset(rx_ring->buffer_info, 0, size);

	for (i = 0; i < rx_ring->count; i++) {
		buffer_info = &rx_ring->buffer_info[i];
		buffer_info->ps_pages = kcalloc(PS_PAGE_BUFFERS,
						sizeof(struct e1000_ps_page),
						GFP_KERNEL);
		if (!buffer_info->ps_pages)
			goto err_pages;
	}

	desc_len = sizeof(union e1000_rx_desc_packet_split);

	/* Round up to nearest 4K */
	rx_ring->size = rx_ring->count * desc_len;
	rx_ring->size = ALIGN(rx_ring->size, 4096);

	err = e1000_alloc_ring_dma(adapter, rx_ring);
	if (err)
		goto err_pages;

	rx_ring->next_to_clean = 0;
	rx_ring->next_to_use = 0;
	rx_ring->rx_skb_top = NULL;

	return 0;

err_pages:
	for (i = 0; i < rx_ring->count; i++) {
		buffer_info = &rx_ring->buffer_info[i];
		kfree(buffer_info->ps_pages);
	}
err:
	vfree(rx_ring->buffer_info);
	e_err("Unable to allocate memory for the receive descriptor ring\n");
	return err;
}

/**
 * e1000_clean_tx_ring - Free Tx Buffers
 * @adapter: board private structure
 **/
static void e1000_clean_tx_ring(struct e1000_adapter *adapter)
{
	struct e1000_ring *tx_ring = adapter->tx_ring;
	struct e1000_buffer *buffer_info;
	unsigned long size;
	unsigned int i;

	for (i = 0; i < tx_ring->count; i++) {
		buffer_info = &tx_ring->buffer_info[i];
		e1000_put_txbuf(adapter, buffer_info);
	}

	size = sizeof(struct e1000_buffer) * tx_ring->count;
	memset(tx_ring->buffer_info, 0, size);

	memset(tx_ring->desc, 0, tx_ring->size);

	tx_ring->next_to_use = 0;
	tx_ring->next_to_clean = 0;

	writel(0, adapter->hw.hw_addr + tx_ring->head);
	writel(0, adapter->hw.hw_addr + tx_ring->tail);
}

/**
 * e1000e_free_tx_resources - Free Tx Resources per Queue
 * @adapter: board private structure
 *
 * Free all transmit software resources
 **/
void e1000e_free_tx_resources(struct e1000_adapter *adapter)
{
	struct pci_dev *pdev = adapter->pdev;
	struct e1000_ring *tx_ring = adapter->tx_ring;

	e1000_clean_tx_ring(adapter);

	vfree(tx_ring->buffer_info);
	tx_ring->buffer_info = NULL;

	dma_free_coherent(&pdev->dev, tx_ring->size, tx_ring->desc,
			  tx_ring->dma);
	tx_ring->desc = NULL;
}

/**
 * e1000e_free_rx_resources - Free Rx Resources
 * @adapter: board private structure
 *
 * Free all receive software resources
 **/

void e1000e_free_rx_resources(struct e1000_adapter *adapter)
{
	struct pci_dev *pdev = adapter->pdev;
	struct e1000_ring *rx_ring = adapter->rx_ring;
	int i;

	e1000_clean_rx_ring(adapter);

	for (i = 0; i < rx_ring->count; i++) {
		kfree(rx_ring->buffer_info[i].ps_pages);
	}

	vfree(rx_ring->buffer_info);
	rx_ring->buffer_info = NULL;

	dma_free_coherent(&pdev->dev, rx_ring->size, rx_ring->desc,
			  rx_ring->dma);
	rx_ring->desc = NULL;
}

/**
 * e1000_update_itr - update the dynamic ITR value based on statistics
 * @adapter: pointer to adapter
 * @itr_setting: current adapter->itr
 * @packets: the number of packets during this measurement interval
 * @bytes: the number of bytes during this measurement interval
 *
 *      Stores a new ITR value based on packets and byte
 *      counts during the last interrupt.  The advantage of per interrupt
 *      computation is faster updates and more accurate ITR for the current
 *      traffic pattern.  Constants in this function were computed
 *      based on theoretical maximum wire speed and thresholds were set based
 *      on testing data as well as attempting to minimize response time
 *      while increasing bulk throughput.  This functionality is controlled
 *      by the InterruptThrottleRate module parameter.
 **/
static unsigned int e1000_update_itr(struct e1000_adapter *adapter,
				     u16 itr_setting, int packets,
				     int bytes)
{
	unsigned int retval = itr_setting;

	if (packets == 0)
		goto update_itr_done;

	switch (itr_setting) {
	case lowest_latency:
		/* handle TSO and jumbo frames */
		if (bytes/packets > 8000)
			retval = bulk_latency;
		else if ((packets < 5) && (bytes > 512)) {
			retval = low_latency;
		}
		break;
	case low_latency:  /* 50 usec aka 20000 ints/s */
		if (bytes > 10000) {
			/* this if handles the TSO accounting */
			if (bytes/packets > 8000) {
				retval = bulk_latency;
			} else if ((packets < 10) || ((bytes/packets) > 1200)) {
				retval = bulk_latency;
			} else if ((packets > 35)) {
				retval = lowest_latency;
			}
		} else if (bytes/packets > 2000) {
			retval = bulk_latency;
		} else if (packets <= 2 && bytes < 512) {
			retval = lowest_latency;
		}
		break;
	case bulk_latency: /* 250 usec aka 4000 ints/s */
		if (bytes > 25000) {
			if (packets > 35) {
				retval = low_latency;
			}
		} else if (bytes < 6000) {
			retval = low_latency;
		}
		break;
	}

update_itr_done:
	return retval;
}

static void e1000_set_itr(struct e1000_adapter *adapter)
{
	struct e1000_hw *hw = &adapter->hw;
	u16 current_itr;
	u32 new_itr = adapter->itr;

	/* for non-gigabit speeds, just fix the interrupt rate at 4000 */
	if (adapter->link_speed != SPEED_1000) {
		current_itr = 0;
		new_itr = 4000;
		goto set_itr_now;
	}

	adapter->tx_itr = e1000_update_itr(adapter,
				    adapter->tx_itr,
				    adapter->total_tx_packets,
				    adapter->total_tx_bytes);
	/* conservative mode (itr 3) eliminates the lowest_latency setting */
	if (adapter->itr_setting == 3 && adapter->tx_itr == lowest_latency)
		adapter->tx_itr = low_latency;

	adapter->rx_itr = e1000_update_itr(adapter,
				    adapter->rx_itr,
				    adapter->total_rx_packets,
				    adapter->total_rx_bytes);
	/* conservative mode (itr 3) eliminates the lowest_latency setting */
	if (adapter->itr_setting == 3 && adapter->rx_itr == lowest_latency)
		adapter->rx_itr = low_latency;

	current_itr = max(adapter->rx_itr, adapter->tx_itr);

	switch (current_itr) {
	/* counts and packets in update_itr are dependent on these numbers */
	case lowest_latency:
		new_itr = 70000;
		break;
	case low_latency:
		new_itr = 20000; /* aka hwitr = ~200 */
		break;
	case bulk_latency:
		new_itr = 4000;
		break;
	default:
		break;
	}

set_itr_now:
	if (new_itr != adapter->itr) {
		/*
		 * this attempts to bias the interrupt rate towards Bulk
		 * by adding intermediate steps when interrupt rate is
		 * increasing
		 */
		new_itr = new_itr > adapter->itr ?
			     min(adapter->itr + (new_itr >> 2), new_itr) :
			     new_itr;
		adapter->itr = new_itr;
#ifdef CONFIG_E1000E_MSIX
		adapter->rx_ring->itr_val = new_itr;
		if (adapter->msix_entries)
			adapter->rx_ring->set_itr = 1;
		else
			ew32(ITR, 1000000000 / (new_itr * 256));
#else
		ew32(ITR, 1000000000 / (new_itr * 256));
#endif
	}
}

/**
 * e1000_alloc_queues - Allocate memory for all rings
 * @adapter: board private structure to initialize
 **/
static int __devinit e1000_alloc_queues(struct e1000_adapter *adapter)
{
	adapter->tx_ring = kzalloc(sizeof(struct e1000_ring), GFP_KERNEL);
	if (!adapter->tx_ring)
		goto err;

	adapter->rx_ring = kzalloc(sizeof(struct e1000_ring), GFP_KERNEL);
	if (!adapter->rx_ring)
		goto err;

	return 0;
err:
	e_err("Unable to allocate memory for queues\n");
	kfree(adapter->rx_ring);
	kfree(adapter->tx_ring);
	return -ENOMEM;
}

#ifdef CONFIG_E1000E_NAPI
/**
 * e1000_poll - NAPI Rx polling callback
 * @napi: struct associated with this polling callback
 * @budget: amount of packets driver is allowed to process this poll
 **/
static int e1000_poll(struct napi_struct *napi, int budget)
{
	struct e1000_adapter *adapter = container_of(napi, struct e1000_adapter,
						     napi);
	struct net_device *netdev = adapter->netdev;
	int tx_clean_complete = 1, work_done = 0;
#ifdef CONFIG_E1000E_MSIX
	struct e1000_hw *hw = &adapter->hw;

	if (adapter->msix_entries &&
	    !(adapter->rx_ring->ims_val & adapter->tx_ring->ims_val))
		goto clean_rx;

#endif
	/*
	 * e1000_poll is called per-cpu.  This lock protects
	 * tx_ring from being cleaned by multiple cpus
	 * simultaneously.  A failure obtaining the lock means
	 * tx_ring is currently being cleaned anyway.
	 */
	if (spin_trylock(&adapter->tx_queue_lock)) {
		tx_clean_complete &= e1000_clean_tx_irq(adapter);
		spin_unlock(&adapter->tx_queue_lock);
	}

#ifdef CONFIG_E1000E_MSIX
clean_rx:
#endif
	adapter->clean_rx(adapter, &work_done, budget);

	/* If Tx completed and all Rx work don