via-velocity.c

linux 内核源代码

 *	Replace the current skb that is scheduled for Rx processing by a
 *	shorter, immediatly allocated skb, if the received packet is small
 *	enough. This function returns a negative value if the received
 *	packet is too big or if memory is exhausted.
 */
static inline int velocity_rx_copy(struct sk_buff **rx_skb, int pkt_size,
				   struct velocity_info *vptr)
{
	int ret = -1;

	if (pkt_size < rx_copybreak) {
		struct sk_buff *new_skb;

		new_skb = dev_alloc_skb(pkt_size + 2);
		if (new_skb) {
			new_skb->dev = vptr->dev;
			new_skb->ip_summed = rx_skb[0]->ip_summed;

			if (vptr->flags & VELOCITY_FLAGS_IP_ALIGN)
				skb_reserve(new_skb, 2);

			skb_copy_from_linear_data(rx_skb[0], new_skb->data,
						  pkt_size);
			*rx_skb = new_skb;
			ret = 0;
		}

	}
	return ret;
}

/**
 *	velocity_iph_realign	-	IP header alignment
 *	@vptr: velocity we are handling
 *	@skb: network layer packet buffer
 *	@pkt_size: received data size
 *
 *	Align IP header on a 2 bytes boundary. This behavior can be
 *	configured by the user.
 */
static inline void velocity_iph_realign(struct velocity_info *vptr,
					struct sk_buff *skb, int pkt_size)
{
	/* FIXME - memmove ? */
	if (vptr->flags & VELOCITY_FLAGS_IP_ALIGN) {
		int i;

		for (i = pkt_size; i >= 0; i--)
			*(skb->data + i + 2) = *(skb->data + i);
		skb_reserve(skb, 2);
	}
}

/**
 *	velocity_receive_frame	-	received packet processor
 *	@vptr: velocity we are handling
 *	@idx: ring index
 *
 *	A packet has arrived. We process the packet and if appropriate
 *	pass the frame up the network stack
 */

static int velocity_receive_frame(struct velocity_info *vptr, int idx)
{
	void (*pci_action)(struct pci_dev *, dma_addr_t, size_t, int);
	struct net_device_stats *stats = &vptr->stats;
	struct velocity_rd_info *rd_info = &(vptr->rd_info[idx]);
	struct rx_desc *rd = &(vptr->rd_ring[idx]);
	int pkt_len = rd->rdesc0.len;
	struct sk_buff *skb;

	if (rd->rdesc0.RSR & (RSR_STP | RSR_EDP)) {
		VELOCITY_PRT(MSG_LEVEL_VERBOSE, KERN_ERR " %s : the received frame span multple RDs.\n", vptr->dev->name);
		stats->rx_length_errors++;
		return -EINVAL;
	}

	if (rd->rdesc0.RSR & RSR_MAR)
		vptr->stats.multicast++;

	skb = rd_info->skb;

	pci_dma_sync_single_for_cpu(vptr->pdev, rd_info->skb_dma,
				    vptr->rx_buf_sz, PCI_DMA_FROMDEVICE);

	/*
	 *	Drop frame not meeting IEEE 802.3
	 */

	if (vptr->flags & VELOCITY_FLAGS_VAL_PKT_LEN) {
		if (rd->rdesc0.RSR & RSR_RL) {
			stats->rx_length_errors++;
			return -EINVAL;
		}
	}

	pci_action = pci_dma_sync_single_for_device;

	velocity_rx_csum(rd, skb);

	if (velocity_rx_copy(&skb, pkt_len, vptr) < 0) {
		velocity_iph_realign(vptr, skb, pkt_len);
		pci_action = pci_unmap_single;
		rd_info->skb = NULL;
	}

	pci_action(vptr->pdev, rd_info->skb_dma, vptr->rx_buf_sz,
		   PCI_DMA_FROMDEVICE);

	skb_put(skb, pkt_len - 4);
	skb->protocol = eth_type_trans(skb, vptr->dev);

	stats->rx_bytes += pkt_len;
	netif_rx(skb);

	return 0;
}

/**
 *	velocity_alloc_rx_buf	-	allocate aligned receive buffer
 *	@vptr: velocity
 *	@idx: ring index
 *
 *	Allocate a new full sized buffer for the reception of a frame and
 *	map it into PCI space for the hardware to use. The hardware
 *	requires *64* byte alignment of the buffer which makes life
 *	less fun than would be ideal.
 */

static int velocity_alloc_rx_buf(struct velocity_info *vptr, int idx)
{
	struct rx_desc *rd = &(vptr->rd_ring[idx]);
	struct velocity_rd_info *rd_info = &(vptr->rd_info[idx]);

	rd_info->skb = dev_alloc_skb(vptr->rx_buf_sz + 64);
	if (rd_info->skb == NULL)
		return -ENOMEM;

	/*
	 *	Do the gymnastics to get the buffer head for data at
	 *	64byte alignment.
	 */
	skb_reserve(rd_info->skb, (unsigned long) rd_info->skb->data & 63);
	rd_info->skb->dev = vptr->dev;
	rd_info->skb_dma = pci_map_single(vptr->pdev, rd_info->skb->data, vptr->rx_buf_sz, PCI_DMA_FROMDEVICE);

	/*
	 *	Fill in the descriptor to match
 	 */

	*((u32 *) & (rd->rdesc0)) = 0;
	rd->len = cpu_to_le32(vptr->rx_buf_sz);
	rd->inten = 1;
	rd->pa_low = cpu_to_le32(rd_info->skb_dma);
	rd->pa_high = 0;
	return 0;
}

/**
 *	tx_srv		-	transmit interrupt service
 *	@vptr; Velocity
 *	@status:
 *
 *	Scan the queues looking for transmitted packets that
 *	we can complete and clean up. Update any statistics as
 *	necessary/
 */

static int velocity_tx_srv(struct velocity_info *vptr, u32 status)
{
	struct tx_desc *td;
	int qnum;
	int full = 0;
	int idx;
	int works = 0;
	struct velocity_td_info *tdinfo;
	struct net_device_stats *stats = &vptr->stats;

	for (qnum = 0; qnum < vptr->num_txq; qnum++) {
		for (idx = vptr->td_tail[qnum]; vptr->td_used[qnum] > 0;
			idx = (idx + 1) % vptr->options.numtx) {

			/*
			 *	Get Tx Descriptor
			 */
			td = &(vptr->td_rings[qnum][idx]);
			tdinfo = &(vptr->td_infos[qnum][idx]);

			if (td->tdesc0.owner == OWNED_BY_NIC)
				break;

			if ((works++ > 15))
				break;

			if (td->tdesc0.TSR & TSR0_TERR) {
				stats->tx_errors++;
				stats->tx_dropped++;
				if (td->tdesc0.TSR & TSR0_CDH)
					stats->tx_heartbeat_errors++;
				if (td->tdesc0.TSR & TSR0_CRS)
					stats->tx_carrier_errors++;
				if (td->tdesc0.TSR & TSR0_ABT)
					stats->tx_aborted_errors++;
				if (td->tdesc0.TSR & TSR0_OWC)
					stats->tx_window_errors++;
			} else {
				stats->tx_packets++;
				stats->tx_bytes += tdinfo->skb->len;
			}
			velocity_free_tx_buf(vptr, tdinfo);
			vptr->td_used[qnum]--;
		}
		vptr->td_tail[qnum] = idx;

		if (AVAIL_TD(vptr, qnum) < 1) {
			full = 1;
		}
	}
	/*
	 *	Look to see if we should kick the transmit network
	 *	layer for more work.
	 */
	if (netif_queue_stopped(vptr->dev) && (full == 0)
	    && (!(vptr->mii_status & VELOCITY_LINK_FAIL))) {
		netif_wake_queue(vptr->dev);
	}
	return works;
}

/**
 *	velocity_print_link_status	-	link status reporting
 *	@vptr: velocity to report on
 *
 *	Turn the link status of the velocity card into a kernel log
 *	description of the new link state, detailing speed and duplex
 *	status
 */

static void velocity_print_link_status(struct velocity_info *vptr)
{

	if (vptr->mii_status & VELOCITY_LINK_FAIL) {
		VELOCITY_PRT(MSG_LEVEL_INFO, KERN_NOTICE "%s: failed to detect cable link\n", vptr->dev->name);
	} else if (vptr->options.spd_dpx == SPD_DPX_AUTO) {
		VELOCITY_PRT(MSG_LEVEL_INFO, KERN_NOTICE "%s: Link auto-negotiation", vptr->dev->name);

		if (vptr->mii_status & VELOCITY_SPEED_1000)
			VELOCITY_PRT(MSG_LEVEL_INFO, " speed 1000M bps");
		else if (vptr->mii_status & VELOCITY_SPEED_100)
			VELOCITY_PRT(MSG_LEVEL_INFO, " speed 100M bps");
		else
			VELOCITY_PRT(MSG_LEVEL_INFO, " speed 10M bps");

		if (vptr->mii_status & VELOCITY_DUPLEX_FULL)
			VELOCITY_PRT(MSG_LEVEL_INFO, " full duplex\n");
		else
			VELOCITY_PRT(MSG_LEVEL_INFO, " half duplex\n");
	} else {
		VELOCITY_PRT(MSG_LEVEL_INFO, KERN_NOTICE "%s: Link forced", vptr->dev->name);
		switch (vptr->options.spd_dpx) {
		case SPD_DPX_100_HALF:
			VELOCITY_PRT(MSG_LEVEL_INFO, " speed 100M bps half duplex\n");
			break;
		case SPD_DPX_100_FULL:
			VELOCITY_PRT(MSG_LEVEL_INFO, " speed 100M bps full duplex\n");
			break;
		case SPD_DPX_10_HALF:
			VELOCITY_PRT(MSG_LEVEL_INFO, " speed 10M bps half duplex\n");
			break;
		case SPD_DPX_10_FULL:
			VELOCITY_PRT(MSG_LEVEL_INFO, " speed 10M bps full duplex\n");
			break;
		default:
			break;
		}
	}
}

/**
 *	velocity_error	-	handle error from controller
 *	@vptr: velocity
 *	@status: card status
 *
 *	Process an error report from the hardware and attempt to recover
 *	the card itself. At the moment we cannot recover from some
 *	theoretically impossible errors but this could be fixed using
 *	the pci_device_failed logic to bounce the hardware
 *
 */

static void velocity_error(struct velocity_info *vptr, int status)
{

	if (status & ISR_TXSTLI) {
		struct mac_regs __iomem * regs = vptr->mac_regs;

		printk(KERN_ERR "TD structure error TDindex=%hx\n", readw(&regs->TDIdx[0]));
		BYTE_REG_BITS_ON(TXESR_TDSTR, &regs->TXESR);
		writew(TRDCSR_RUN, &regs->TDCSRClr);
		netif_stop_queue(vptr->dev);

		/* FIXME: port over the pci_device_failed code and use it
		   here */
	}

	if (status & ISR_SRCI) {
		struct mac_regs __iomem * regs = vptr->mac_regs;
		int linked;

		if (vptr->options.spd_dpx == SPD_DPX_AUTO) {
			vptr->mii_status = check_connection_type(regs);

			/*
			 *	If it is a 3119, disable frame bursting in
			 *	halfduplex mode and enable it in fullduplex
			 *	 mode
			 */
			if (vptr->rev_id < REV_ID_VT3216_A0) {
				if (vptr->mii_status | VELOCITY_DUPLEX_FULL)
					BYTE_REG_BITS_ON(TCR_TB2BDIS, &regs->TCR);
				else
					BYTE_REG_BITS_OFF(TCR_TB2BDIS, &regs->TCR);
			}
			/*
			 *	Only enable CD heart beat counter in 10HD mode
			 */
			if (!(vptr->mii_status & VELOCITY_DUPLEX_FULL) && (vptr->mii_status & VELOCITY_SPEED_10)) {
				BYTE_REG_BITS_OFF(TESTCFG_HBDIS, &regs->TESTCFG);
			} else {
				BYTE_REG_BITS_ON(TESTCFG_HBDIS, &regs->TESTCFG);
			}
		}
		/*
		 *	Get link status from PHYSR0
		 */
		linked = readb(&regs->PHYSR0) & PHYSR0_LINKGD;

		if (linked) {
			vptr->mii_status &= ~VELOCITY_LINK_FAIL;
			netif_carrier_on(vptr->dev);
		} else {
			vptr->mii_status |= VELOCITY_LINK_FAIL;
			netif_carrier_off(vptr->dev);
		}

		velocity_print_link_status(vptr);
		enable_flow_control_ability(vptr);

		/*
		 *	Re-enable auto-polling because SRCI will disable
		 *	auto-polling
		 */

		enable_mii_autopoll(regs);

		if (vptr->mii_status & VELOCITY_LINK_FAIL)
			netif_stop_queue(vptr->dev);
		else
			netif_wake_queue(vptr->dev);

	};
	if (status & ISR_MIBFI)
		velocity_update_hw_mibs(vptr);
	if (status & ISR_LSTEI)
		mac_rx_queue_wake(vptr->mac_regs);
}

/**
 *	velocity_free_tx_buf	-	free transmit buffer
 *	@vptr: velocity
 *	@tdinfo: buffer
 *
 *	Release an transmit buffer. If the buffer was preallocated then
 *	recycle it, if not then unmap the buffer.
 */

static void velocity_free_tx_buf(struct velocity_info *vptr, struct velocity_td_info *tdinfo)
{
	struct sk_buff *skb = tdinfo->skb;
	int i;

	/*
	 *	Don't unmap the pre-allocated tx_bufs
	 */
	if (tdinfo->skb_dma && (tdinfo->skb_dma[0] != tdinfo->buf_dma)) {

		for (i = 0; i < tdinfo->nskb_dma; i++) {
#ifdef VELOCITY_ZERO_COPY_SUPPORT
			pci_unmap_single(vptr->pdev, tdinfo->skb_dma[i], td->tdesc1.len, PCI_DMA_TODEVICE);
#else
			pci_unmap_single(vptr->pdev, tdinfo->skb_dma[i], skb->len, PCI_DMA_TODEVICE);
#endif
			tdinfo->skb_dma[i] = 0;
		}
	}
	dev_kfree_skb_irq(skb);
	tdinfo->skb = NULL;
}

/**
 *	velocity_open		-	interface activation callback
 *	@dev: network layer device to open
 *
 *	Called when the network layer brings the interface up. Returns
 *	a negative posix error code on failure, or zero on success.
 *
 *	All the ring allocation and set up is done on open for this
 *	adapter to minimise memory usage when inactive
 */

static int velocity_open(struct net_device *dev)
{
	struct velocity_info *vptr = netdev_priv(dev);
	int ret;

	ret = velocity_init_rings(vptr);
	if (ret < 0)
		goto out;

	ret = velocity_init_rd_ring(vptr);
	if (ret < 0)
		goto err_free_desc_rings;

	ret = velocity_init_td_ring(vptr);
	if (ret < 0)
		goto err_free_rd_ring;

	/* Ensure chip is running */
	pci_set_power_state(vptr->pdev, PCI_D0);

	velocity_init_registers(vptr, VELOCITY_INIT_COLD);

	ret = request_irq(vptr->pdev->irq, &velocity_intr, IRQF_SHARED,
			  dev->name, dev);
	if (ret < 0) {
		/* Power down the chip */
		pci_set_power_state(vptr->pdev, PCI_D3hot);
		goto err_free_td_ring;
	}

	mac_enable_int(vptr->mac_regs);
	netif_start_queue(dev);
	vptr->flags |= VELOCITY_FLAGS_OPENED;
out:
	return ret;

err_free_td_ring:
	velocity_free_td_ring(vptr);
err_free_rd_ring:
	velocity_free_rd_ring(vptr);
err_free_desc_rings:
	velocity_free_rings(vptr);
	goto out;
}

/**
 *	velocity_change_mtu	-	MTU change callback
 *	@dev: network device
 *	@new_mtu: desired MTU
 *
 *	Handle requests from the networking layer for MTU change on
 *	this interface. It gets called on a change by the network layer.
 *	Return zero for success or negative posix error code.
 */

static int velocity_change_mtu(struct net_device *dev, int new_mtu)
{
	struct velocity_info *vptr = netdev_priv(dev);
	unsigned long flags;
	int oldmtu = dev->mtu;
	int ret = 0;

	if ((new_mtu < VELOCITY_MIN_MTU) || new_mtu > (VELOCITY_MAX_MTU)) {
		VELOCITY_PRT(MSG_LEVEL_ERR, KERN_NOTICE "%s: Invalid MTU.\n",
				vptr->dev->name);
		return -EINVAL;
	}

	if (!netif_running(dev)) {
		dev->mtu = new_mtu;
		return 0;
	}

	if (new_mtu != oldmtu) {
		spin_lock_irqsave(&vptr->lock, flags);

		netif_stop_queue(dev);
		velocity_shutdown(vptr);

		velocity_free_td_ring(vptr);
		velocity_free_rd_ring(vptr);

		dev->mtu = new_mtu;

		ret = velocity_init_rd_ring(vptr);
		if (ret < 0)