atl1_main.c

linux 内核源代码

		tpd_next_to_use = atomic_read(&adapter->tpd_ring.next_to_use);
		rfd_next_to_use =
		    atomic_read(&adapter->rfd_ring.next_to_use);
		rrd_next_to_clean =
		    atomic_read(&adapter->rrd_ring.next_to_clean);
		value = ((rfd_next_to_use & MB_RFD_PROD_INDX_MASK) <<
			MB_RFD_PROD_INDX_SHIFT) |
                        ((rrd_next_to_clean & MB_RRD_CONS_INDX_MASK) <<
			MB_RRD_CONS_INDX_SHIFT) |
                        ((tpd_next_to_use & MB_TPD_PROD_INDX_MASK) <<
			MB_TPD_PROD_INDX_SHIFT);
		iowrite32(value, adapter->hw.hw_addr + REG_MAILBOX);
		spin_unlock(&adapter->mb_lock);
	}
}

static void atl1_intr_tx(struct atl1_adapter *adapter)
{
	struct atl1_tpd_ring *tpd_ring = &adapter->tpd_ring;
	struct atl1_buffer *buffer_info;
	u16 sw_tpd_next_to_clean;
	u16 cmb_tpd_next_to_clean;

	sw_tpd_next_to_clean = atomic_read(&tpd_ring->next_to_clean);
	cmb_tpd_next_to_clean = le16_to_cpu(adapter->cmb.cmb->tpd_cons_idx);

	while (cmb_tpd_next_to_clean != sw_tpd_next_to_clean) {
		struct tx_packet_desc *tpd;

		tpd = ATL1_TPD_DESC(tpd_ring, sw_tpd_next_to_clean);
		buffer_info = &tpd_ring->buffer_info[sw_tpd_next_to_clean];
		if (buffer_info->dma) {
			pci_unmap_page(adapter->pdev, buffer_info->dma,
				       buffer_info->length, PCI_DMA_TODEVICE);
			buffer_info->dma = 0;
		}

		if (buffer_info->skb) {
			dev_kfree_skb_irq(buffer_info->skb);
			buffer_info->skb = NULL;
		}
		tpd->buffer_addr = 0;
		tpd->desc.data = 0;

		if (++sw_tpd_next_to_clean == tpd_ring->count)
			sw_tpd_next_to_clean = 0;
	}
	atomic_set(&tpd_ring->next_to_clean, sw_tpd_next_to_clean);

	if (netif_queue_stopped(adapter->netdev)
	    && netif_carrier_ok(adapter->netdev))
		netif_wake_queue(adapter->netdev);
}

static u16 atl1_tpd_avail(struct atl1_tpd_ring *tpd_ring)
{
	u16 next_to_clean = atomic_read(&tpd_ring->next_to_clean);
	u16 next_to_use = atomic_read(&tpd_ring->next_to_use);
	return ((next_to_clean > next_to_use) ?
		next_to_clean - next_to_use - 1 :
		tpd_ring->count + next_to_clean - next_to_use - 1);
}

static int atl1_tso(struct atl1_adapter *adapter, struct sk_buff *skb,
			 struct tso_param *tso)
{
	/* We enter this function holding a spinlock. */
	u8 ipofst;
	int err;

	if (skb_shinfo(skb)->gso_size) {
		if (skb_header_cloned(skb)) {
			err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC);
			if (unlikely(err))
				return err;
		}

		if (skb->protocol == ntohs(ETH_P_IP)) {
			struct iphdr *iph = ip_hdr(skb);

			iph->tot_len = 0;
			iph->check = 0;
			tcp_hdr(skb)->check = ~csum_tcpudp_magic(iph->saddr,
				iph->daddr, 0, IPPROTO_TCP, 0);
			ipofst = skb_network_offset(skb);
			if (ipofst != ETH_HLEN) /* 802.3 frame */
				tso->tsopl |= 1 << TSO_PARAM_ETHTYPE_SHIFT;

			tso->tsopl |= (iph->ihl &
				CSUM_PARAM_IPHL_MASK) << CSUM_PARAM_IPHL_SHIFT;
			tso->tsopl |= (tcp_hdrlen(skb) &
				TSO_PARAM_TCPHDRLEN_MASK) <<
				TSO_PARAM_TCPHDRLEN_SHIFT;
			tso->tsopl |= (skb_shinfo(skb)->gso_size &
				TSO_PARAM_MSS_MASK) << TSO_PARAM_MSS_SHIFT;
			tso->tsopl |= 1 << TSO_PARAM_IPCKSUM_SHIFT;
			tso->tsopl |= 1 << TSO_PARAM_TCPCKSUM_SHIFT;
			tso->tsopl |= 1 << TSO_PARAM_SEGMENT_SHIFT;
			return true;
		}
	}
	return false;
}

static int atl1_tx_csum(struct atl1_adapter *adapter, struct sk_buff *skb,
	struct csum_param *csum)
{
	u8 css, cso;

	if (likely(skb->ip_summed == CHECKSUM_PARTIAL)) {
		cso = skb_transport_offset(skb);
		css = cso + skb->csum_offset;
		if (unlikely(cso & 0x1)) {
			dev_printk(KERN_DEBUG, &adapter->pdev->dev,
				"payload offset not an even number\n");
			return -1;
		}
		csum->csumpl |= (cso & CSUM_PARAM_PLOADOFFSET_MASK) <<
			CSUM_PARAM_PLOADOFFSET_SHIFT;
		csum->csumpl |= (css & CSUM_PARAM_XSUMOFFSET_MASK) <<
			CSUM_PARAM_XSUMOFFSET_SHIFT;
		csum->csumpl |= 1 << CSUM_PARAM_CUSTOMCKSUM_SHIFT;
		return true;
	}

	return true;
}

static void atl1_tx_map(struct atl1_adapter *adapter, struct sk_buff *skb,
	bool tcp_seg)
{
	/* We enter this function holding a spinlock. */
	struct atl1_tpd_ring *tpd_ring = &adapter->tpd_ring;
	struct atl1_buffer *buffer_info;
	struct page *page;
	int first_buf_len = skb->len;
	unsigned long offset;
	unsigned int nr_frags;
	unsigned int f;
	u16 tpd_next_to_use;
	u16 proto_hdr_len;
	u16 len12;

	first_buf_len -= skb->data_len;
	nr_frags = skb_shinfo(skb)->nr_frags;
	tpd_next_to_use = atomic_read(&tpd_ring->next_to_use);
	buffer_info = &tpd_ring->buffer_info[tpd_next_to_use];
	if (unlikely(buffer_info->skb))
		BUG();
	buffer_info->skb = NULL;	/* put skb in last TPD */

	if (tcp_seg) {
		/* TSO/GSO */
		proto_hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
		buffer_info->length = proto_hdr_len;
		page = virt_to_page(skb->data);
		offset = (unsigned long)skb->data & ~PAGE_MASK;
		buffer_info->dma = pci_map_page(adapter->pdev, page,
						offset, proto_hdr_len,
						PCI_DMA_TODEVICE);

		if (++tpd_next_to_use == tpd_ring->count)
			tpd_next_to_use = 0;

		if (first_buf_len > proto_hdr_len) {
			int i, m;

			len12 = first_buf_len - proto_hdr_len;
			m = (len12 + ATL1_MAX_TX_BUF_LEN - 1) /
				ATL1_MAX_TX_BUF_LEN;
			for (i = 0; i < m; i++) {
				buffer_info =
				    &tpd_ring->buffer_info[tpd_next_to_use];
				buffer_info->skb = NULL;
				buffer_info->length =
				    (ATL1_MAX_TX_BUF_LEN >=
				     len12) ? ATL1_MAX_TX_BUF_LEN : len12;
				len12 -= buffer_info->length;
				page = virt_to_page(skb->data +
					(proto_hdr_len +
					i * ATL1_MAX_TX_BUF_LEN));
				offset = (unsigned long)(skb->data +
					(proto_hdr_len +
					i * ATL1_MAX_TX_BUF_LEN)) & ~PAGE_MASK;
				buffer_info->dma = pci_map_page(adapter->pdev,
					page, offset, buffer_info->length,
					PCI_DMA_TODEVICE);
				if (++tpd_next_to_use == tpd_ring->count)
					tpd_next_to_use = 0;
			}
		}
	} else {
		/* not TSO/GSO */
		buffer_info->length = first_buf_len;
		page = virt_to_page(skb->data);
		offset = (unsigned long)skb->data & ~PAGE_MASK;
		buffer_info->dma = pci_map_page(adapter->pdev, page,
			offset, first_buf_len, PCI_DMA_TODEVICE);
		if (++tpd_next_to_use == tpd_ring->count)
			tpd_next_to_use = 0;
	}

	for (f = 0; f < nr_frags; f++) {
		struct skb_frag_struct *frag;
		u16 lenf, i, m;

		frag = &skb_shinfo(skb)->frags[f];
		lenf = frag->size;

		m = (lenf + ATL1_MAX_TX_BUF_LEN - 1) / ATL1_MAX_TX_BUF_LEN;
		for (i = 0; i < m; i++) {
			buffer_info = &tpd_ring->buffer_info[tpd_next_to_use];
			if (unlikely(buffer_info->skb))
				BUG();
			buffer_info->skb = NULL;
			buffer_info->length = (lenf > ATL1_MAX_TX_BUF_LEN) ?
				ATL1_MAX_TX_BUF_LEN : lenf;
			lenf -= buffer_info->length;
			buffer_info->dma = pci_map_page(adapter->pdev,
				frag->page,
				frag->page_offset + (i * ATL1_MAX_TX_BUF_LEN),
				buffer_info->length, PCI_DMA_TODEVICE);

			if (++tpd_next_to_use == tpd_ring->count)
				tpd_next_to_use = 0;
		}
	}

	/* last tpd's buffer-info */
	buffer_info->skb = skb;
}

static void atl1_tx_queue(struct atl1_adapter *adapter, int count,
       union tpd_descr *descr)
{
	/* We enter this function holding a spinlock. */
	struct atl1_tpd_ring *tpd_ring = &adapter->tpd_ring;
	int j;
	u32 val;
	struct atl1_buffer *buffer_info;
	struct tx_packet_desc *tpd;
	u16 tpd_next_to_use = atomic_read(&tpd_ring->next_to_use);

	for (j = 0; j < count; j++) {
		buffer_info = &tpd_ring->buffer_info[tpd_next_to_use];
		tpd = ATL1_TPD_DESC(&adapter->tpd_ring, tpd_next_to_use);
		tpd->desc.csum.csumpu = descr->csum.csumpu;
		tpd->desc.csum.csumpl = descr->csum.csumpl;
		tpd->desc.tso.tsopu = descr->tso.tsopu;
		tpd->desc.tso.tsopl = descr->tso.tsopl;
		tpd->buffer_addr = cpu_to_le64(buffer_info->dma);
		tpd->desc.data = descr->data;
		tpd->desc.csum.csumpu |= (cpu_to_le16(buffer_info->length) &
			CSUM_PARAM_BUFLEN_MASK) << CSUM_PARAM_BUFLEN_SHIFT;

		val = (descr->tso.tsopl >> TSO_PARAM_SEGMENT_SHIFT) &
			TSO_PARAM_SEGMENT_MASK;
		if (val && !j)
			tpd->desc.tso.tsopl |= 1 << TSO_PARAM_HDRFLAG_SHIFT;

		if (j == (count - 1))
			tpd->desc.csum.csumpl |= 1 << CSUM_PARAM_EOP_SHIFT;

		if (++tpd_next_to_use == tpd_ring->count)
			tpd_next_to_use = 0;
	}
	/*
	 * 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();

	atomic_set(&tpd_ring->next_to_use, (int)tpd_next_to_use);
}

static int atl1_xmit_frame(struct sk_buff *skb, struct net_device *netdev)
{
	struct atl1_adapter *adapter = netdev_priv(netdev);
	int len = skb->len;
	int tso;
	int count = 1;
	int ret_val;
	u32 val;
	union tpd_descr param;
	u16 frag_size;
	u16 vlan_tag;
	unsigned long flags;
	unsigned int nr_frags = 0;
	unsigned int mss = 0;
	unsigned int f;
	unsigned int proto_hdr_len;

	len -= skb->data_len;

	if (unlikely(skb->len == 0)) {
		dev_kfree_skb_any(skb);
		return NETDEV_TX_OK;
	}

	param.data = 0;
	param.tso.tsopu = 0;
	param.tso.tsopl = 0;
	param.csum.csumpu = 0;
	param.csum.csumpl = 0;

	/* nr_frags will be nonzero if we're doing scatter/gather (SG) */
	nr_frags = skb_shinfo(skb)->nr_frags;
	for (f = 0; f < nr_frags; f++) {
		frag_size = skb_shinfo(skb)->frags[f].size;
		if (frag_size)
			count += (frag_size + ATL1_MAX_TX_BUF_LEN - 1) /
				ATL1_MAX_TX_BUF_LEN;
	}

	/* mss will be nonzero if we're doing segment offload (TSO/GSO) */
	mss = skb_shinfo(skb)->gso_size;
	if (mss) {
		if (skb->protocol == htons(ETH_P_IP)) {
			proto_hdr_len = (skb_transport_offset(skb) +
					 tcp_hdrlen(skb));
			if (unlikely(proto_hdr_len > len)) {
				dev_kfree_skb_any(skb);
				return NETDEV_TX_OK;
			}
			/* need additional TPD ? */
			if (proto_hdr_len != len)
				count += (len - proto_hdr_len +
					ATL1_MAX_TX_BUF_LEN - 1) /
					ATL1_MAX_TX_BUF_LEN;
		}
	}

	if (!spin_trylock_irqsave(&adapter->lock, flags)) {
		/* Can't get lock - tell upper layer to requeue */
		dev_printk(KERN_DEBUG, &adapter->pdev->dev, "tx locked\n");
		return NETDEV_TX_LOCKED;
	}

	if (atl1_tpd_avail(&adapter->tpd_ring) < count) {
		/* not enough descriptors */
		netif_stop_queue(netdev);
		spin_unlock_irqrestore(&adapter->lock, flags);
		dev_printk(KERN_DEBUG, &adapter->pdev->dev, "tx busy\n");
		return NETDEV_TX_BUSY;
	}

	param.data = 0;

	if (adapter->vlgrp && vlan_tx_tag_present(skb)) {
		vlan_tag = vlan_tx_tag_get(skb);
		vlan_tag = (vlan_tag << 4) | (vlan_tag >> 13) |
			((vlan_tag >> 9) & 0x8);
		param.csum.csumpl |= 1 << CSUM_PARAM_INSVLAG_SHIFT;
		param.csum.csumpu |= (vlan_tag & CSUM_PARAM_VALANTAG_MASK) <<
			CSUM_PARAM_VALAN_SHIFT;
	}

	tso = atl1_tso(adapter, skb, &param.tso);
	if (tso < 0) {
		spin_unlock_irqrestore(&adapter->lock, flags);
		dev_kfree_skb_any(skb);
		return NETDEV_TX_OK;
	}

	if (!tso) {
		ret_val = atl1_tx_csum(adapter, skb, &param.csum);
		if (ret_val < 0) {
			spin_unlock_irqrestore(&adapter->lock, flags);
			dev_kfree_skb_any(skb);
			return NETDEV_TX_OK;
		}
	}

	val = (param.csum.csumpl >> CSUM_PARAM_SEGMENT_SHIFT) &
		CSUM_PARAM_SEGMENT_MASK;
	atl1_tx_map(adapter, skb, 1 == val);
	atl1_tx_queue(adapter, count, &param);
	netdev->trans_start = jiffies;
	spin_unlock_irqrestore(&adapter->lock, flags);
	atl1_update_mailbox(adapter);
	return NETDEV_TX_OK;
}

/*
 * atl1_intr - Interrupt Handler
 * @irq: interrupt number
 * @data: pointer to a network interface device structure
 * @pt_regs: CPU registers structure
 */
static irqreturn_t atl1_intr(int irq, void *data)
{
	struct atl1_adapter *adapter = netdev_priv(data);
	u32 status;
	u8 update_rx;
	int max_ints = 10;

	status = adapter->cmb.cmb->int_stats;
	if (!status)
		return IRQ_NONE;

	update_rx = 0;

	do {
		/* clear CMB interrupt status at once */
		adapter->cmb.cmb->int_stats = 0;

		if (status & ISR_GPHY)	/* clear phy status */
			atl1_clear_phy_int(adapter);

		/* clear ISR status, and Enable CMB DMA/Disable Interrupt */
		iowrite32(status | ISR_DIS_INT, adapter->hw.hw_addr + REG_ISR);

		/* check if SMB intr */
		if (status & ISR_SMB)
			atl1_inc_smb(adapter);

		/* check if PCIE PHY Link down */
		if (status & ISR_PHY_LINKDOWN) {
			dev_printk(KERN_DEBUG, &adapter->pdev->dev,
				"pcie phy link down %x\n", status);
			if (netif_running(adapter->netdev)) {	/* reset MAC */
				iowrite32(0, adapter->hw.hw_addr + REG_IMR);
				schedule_work(&adapter->pcie_dma_to_rst_task);
				return IRQ_HANDLED;
			}
		}

		/* check if DMA read/write error ? */
		if (status & (ISR_DMAR_TO_RST | ISR_DMAW_TO_RST)) {
			dev_printk(KERN_DEBUG, &adapter->pdev->dev,
				"pcie DMA r/w error (status = 0x%x)\n",
				status);
			iowrite32(0, adapter->hw.hw_addr + REG_IMR);
			schedule_work(&adapter->pcie_dma_to_rst_task);
			return IRQ_HANDLED;
		}

		/* link event */
		if (status & ISR_GPHY) {
			adapter->soft_stats.tx_carrier_errors++;
			atl1_check_for_link(adapter);
		}

		/* transmit event */
		if (status & ISR_CMB_TX)
			atl1_intr_tx(adapter);

		/* rx exception */
		if (unlikely(status & (ISR_RXF_OV | ISR_RFD_UNRUN |
			ISR_RRD_OV | ISR_HOST_RFD_UNRUN |
			ISR_HOST_RRD_OV | ISR_CMB_RX))) {
			if (status & (ISR_RXF_OV | ISR_RFD_UNRUN |
				ISR_RRD_OV | ISR_HOST_RFD_UNRUN |
				ISR_HOST_RRD_OV))