ibm_emac_core.c

linux-2.6.15.6

	if (likely(!nr_frags && len <= MAL_MAX_TX_SIZE))
		return emac_start_xmit(skb, ndev);

	len -= skb->data_len;

	/* Note, this is only an *estimation*, we can still run out of empty
	 * slots because of the additional fragmentation into
	 * MAL_MAX_TX_SIZE-sized chunks
	 */
	if (unlikely(dev->tx_cnt + nr_frags + mal_tx_chunks(len) > NUM_TX_BUFF))
		goto stop_queue;

	ctrl = EMAC_TX_CTRL_GFCS | EMAC_TX_CTRL_GP | MAL_TX_CTRL_READY |
	    emac_tx_csum(dev, skb);
	slot = dev->tx_slot;

	/* skb data */
	dev->tx_skb[slot] = NULL;
	chunk = min(len, MAL_MAX_TX_SIZE);
	dev->tx_desc[slot].data_ptr = pd =
	    dma_map_single(dev->ldev, skb->data, len, DMA_TO_DEVICE);
	dev->tx_desc[slot].data_len = (u16) chunk;
	len -= chunk;
	if (unlikely(len))
		slot = emac_xmit_split(dev, slot, pd + chunk, len, !nr_frags,
				       ctrl);
	/* skb fragments */
	for (i = 0; i < nr_frags; ++i) {
		struct skb_frag_struct *frag = &skb_shinfo(skb)->frags[i];
		len = frag->size;

		if (unlikely(dev->tx_cnt + mal_tx_chunks(len) >= NUM_TX_BUFF))
			goto undo_frame;

		pd = dma_map_page(dev->ldev, frag->page, frag->page_offset, len,
				  DMA_TO_DEVICE);

		slot = emac_xmit_split(dev, slot, pd, len, i == nr_frags - 1,
				       ctrl);
	}

	DBG2("%d: xmit_sg(%u) %d - %d" NL, dev->def->index, skb->len,
	     dev->tx_slot, slot);

	/* Attach skb to the last slot so we don't release it too early */
	dev->tx_skb[slot] = skb;

	/* Send the packet out */
	if (dev->tx_slot == NUM_TX_BUFF - 1)
		ctrl |= MAL_TX_CTRL_WRAP;
	barrier();
	dev->tx_desc[dev->tx_slot].ctrl = ctrl;
	dev->tx_slot = (slot + 1) % NUM_TX_BUFF;

	return emac_xmit_finish(dev, skb->len);

      undo_frame:
	/* Well, too bad. Our previous estimation was overly optimistic. 
	 * Undo everything.
	 */
	while (slot != dev->tx_slot) {
		dev->tx_desc[slot].ctrl = 0;
		--dev->tx_cnt;
		if (--slot < 0)
			slot = NUM_TX_BUFF - 1;
	}
	++dev->estats.tx_undo;

      stop_queue:
	netif_stop_queue(ndev);
	DBG2("%d: stopped TX queue" NL, dev->def->index);
	return 1;
}
#else
# define emac_start_xmit_sg	emac_start_xmit
#endif	/* !defined(CONFIG_IBM_EMAC_TAH) */

/* BHs disabled */
static void emac_parse_tx_error(struct ocp_enet_private *dev, u16 ctrl)
{
	struct ibm_emac_error_stats *st = &dev->estats;
	DBG("%d: BD TX error %04x" NL, dev->def->index, ctrl);

	++st->tx_bd_errors;
	if (ctrl & EMAC_TX_ST_BFCS)
		++st->tx_bd_bad_fcs;
	if (ctrl & EMAC_TX_ST_LCS)
		++st->tx_bd_carrier_loss;
	if (ctrl & EMAC_TX_ST_ED)
		++st->tx_bd_excessive_deferral;
	if (ctrl & EMAC_TX_ST_EC)
		++st->tx_bd_excessive_collisions;
	if (ctrl & EMAC_TX_ST_LC)
		++st->tx_bd_late_collision;
	if (ctrl & EMAC_TX_ST_MC)
		++st->tx_bd_multple_collisions;
	if (ctrl & EMAC_TX_ST_SC)
		++st->tx_bd_single_collision;
	if (ctrl & EMAC_TX_ST_UR)
		++st->tx_bd_underrun;
	if (ctrl & EMAC_TX_ST_SQE)
		++st->tx_bd_sqe;
}

static void emac_poll_tx(void *param)
{
	struct ocp_enet_private *dev = param;
	DBG2("%d: poll_tx, %d %d" NL, dev->def->index, dev->tx_cnt,
	     dev->ack_slot);

	if (dev->tx_cnt) {
		u16 ctrl;
		int slot = dev->ack_slot, n = 0;
	      again:
		ctrl = dev->tx_desc[slot].ctrl;
		if (!(ctrl & MAL_TX_CTRL_READY)) {
			struct sk_buff *skb = dev->tx_skb[slot];
			++n;

			if (skb) {
				dev_kfree_skb(skb);
				dev->tx_skb[slot] = NULL;
			}
			slot = (slot + 1) % NUM_TX_BUFF;

			if (unlikely(EMAC_IS_BAD_TX(ctrl)))
				emac_parse_tx_error(dev, ctrl);

			if (--dev->tx_cnt)
				goto again;
		}
		if (n) {
			dev->ack_slot = slot;
			if (netif_queue_stopped(dev->ndev) &&
			    dev->tx_cnt < EMAC_TX_WAKEUP_THRESH)
				netif_wake_queue(dev->ndev);

			DBG2("%d: tx %d pkts" NL, dev->def->index, n);
		}
	}
}

static inline void emac_recycle_rx_skb(struct ocp_enet_private *dev, int slot,
				       int len)
{
	struct sk_buff *skb = dev->rx_skb[slot];
	DBG2("%d: recycle %d %d" NL, dev->def->index, slot, len);

	if (len) 
		dma_map_single(dev->ldev, skb->data - 2, 
			       EMAC_DMA_ALIGN(len + 2), DMA_FROM_DEVICE);

	dev->rx_desc[slot].data_len = 0;
	barrier();
	dev->rx_desc[slot].ctrl = MAL_RX_CTRL_EMPTY |
	    (slot == (NUM_RX_BUFF - 1) ? MAL_RX_CTRL_WRAP : 0);
}

static void emac_parse_rx_error(struct ocp_enet_private *dev, u16 ctrl)
{
	struct ibm_emac_error_stats *st = &dev->estats;
	DBG("%d: BD RX error %04x" NL, dev->def->index, ctrl);

	++st->rx_bd_errors;
	if (ctrl & EMAC_RX_ST_OE)
		++st->rx_bd_overrun;
	if (ctrl & EMAC_RX_ST_BP)
		++st->rx_bd_bad_packet;
	if (ctrl & EMAC_RX_ST_RP)
		++st->rx_bd_runt_packet;
	if (ctrl & EMAC_RX_ST_SE)
		++st->rx_bd_short_event;
	if (ctrl & EMAC_RX_ST_AE)
		++st->rx_bd_alignment_error;
	if (ctrl & EMAC_RX_ST_BFCS)
		++st->rx_bd_bad_fcs;
	if (ctrl & EMAC_RX_ST_PTL)
		++st->rx_bd_packet_too_long;
	if (ctrl & EMAC_RX_ST_ORE)
		++st->rx_bd_out_of_range;
	if (ctrl & EMAC_RX_ST_IRE)
		++st->rx_bd_in_range;
}

static inline void emac_rx_csum(struct ocp_enet_private *dev,
				struct sk_buff *skb, u16 ctrl)
{
#if defined(CONFIG_IBM_EMAC_TAH)
	if (!ctrl && dev->tah_dev) {
		skb->ip_summed = CHECKSUM_UNNECESSARY;
		++dev->stats.rx_packets_csum;
	}
#endif
}

static inline int emac_rx_sg_append(struct ocp_enet_private *dev, int slot)
{
	if (likely(dev->rx_sg_skb != NULL)) {
		int len = dev->rx_desc[slot].data_len;
		int tot_len = dev->rx_sg_skb->len + len;

		if (unlikely(tot_len + 2 > dev->rx_skb_size)) {
			++dev->estats.rx_dropped_mtu;
			dev_kfree_skb(dev->rx_sg_skb);
			dev->rx_sg_skb = NULL;
		} else {
			cacheable_memcpy(dev->rx_sg_skb->tail,
					 dev->rx_skb[slot]->data, len);
			skb_put(dev->rx_sg_skb, len);
			emac_recycle_rx_skb(dev, slot, len);
			return 0;
		}
	}
	emac_recycle_rx_skb(dev, slot, 0);
	return -1;
}

/* BHs disabled */
static int emac_poll_rx(void *param, int budget)
{
	struct ocp_enet_private *dev = param;
	int slot = dev->rx_slot, received = 0;

	DBG2("%d: poll_rx(%d)" NL, dev->def->index, budget);

      again:
	while (budget > 0) {
		int len;
		struct sk_buff *skb;
		u16 ctrl = dev->rx_desc[slot].ctrl;

		if (ctrl & MAL_RX_CTRL_EMPTY)
			break;

		skb = dev->rx_skb[slot];
		barrier();
		len = dev->rx_desc[slot].data_len;

		if (unlikely(!MAL_IS_SINGLE_RX(ctrl)))
			goto sg;

		ctrl &= EMAC_BAD_RX_MASK;
		if (unlikely(ctrl && ctrl != EMAC_RX_TAH_BAD_CSUM)) {
			emac_parse_rx_error(dev, ctrl);
			++dev->estats.rx_dropped_error;
			emac_recycle_rx_skb(dev, slot, 0);
			len = 0;
			goto next;
		}

		if (len && len < EMAC_RX_COPY_THRESH) {
			struct sk_buff *copy_skb =
			    alloc_skb(len + EMAC_RX_SKB_HEADROOM + 2, GFP_ATOMIC);
			if (unlikely(!copy_skb))
				goto oom;

			skb_reserve(copy_skb, EMAC_RX_SKB_HEADROOM + 2);
			cacheable_memcpy(copy_skb->data - 2, skb->data - 2,
					 len + 2);
			emac_recycle_rx_skb(dev, slot, len);
			skb = copy_skb;
		} else if (unlikely(emac_alloc_rx_skb(dev, slot, GFP_ATOMIC)))
			goto oom;

		skb_put(skb, len);
	      push_packet:
		skb->dev = dev->ndev;
		skb->protocol = eth_type_trans(skb, dev->ndev);
		emac_rx_csum(dev, skb, ctrl);

		if (unlikely(netif_receive_skb(skb) == NET_RX_DROP))
			++dev->estats.rx_dropped_stack;
	      next:
		++dev->stats.rx_packets;
	      skip:
		dev->stats.rx_bytes += len;
		slot = (slot + 1) % NUM_RX_BUFF;
		--budget;
		++received;
		continue;
	      sg:
		if (ctrl & MAL_RX_CTRL_FIRST) {
			BUG_ON(dev->rx_sg_skb);
			if (unlikely(emac_alloc_rx_skb(dev, slot, GFP_ATOMIC))) {
				DBG("%d: rx OOM %d" NL, dev->def->index, slot);
				++dev->estats.rx_dropped_oom;
				emac_recycle_rx_skb(dev, slot, 0);
			} else {
				dev->rx_sg_skb = skb;
				skb_put(skb, len);
			}
		} else if (!emac_rx_sg_append(dev, slot) &&
			   (ctrl & MAL_RX_CTRL_LAST)) {

			skb = dev->rx_sg_skb;
			dev->rx_sg_skb = NULL;

			ctrl &= EMAC_BAD_RX_MASK;
			if (unlikely(ctrl && ctrl != EMAC_RX_TAH_BAD_CSUM)) {
				emac_parse_rx_error(dev, ctrl);
				++dev->estats.rx_dropped_error;
				dev_kfree_skb(skb);
				len = 0;
			} else
				goto push_packet;
		}
		goto skip;
	      oom:
		DBG("%d: rx OOM %d" NL, dev->def->index, slot);
		/* Drop the packet and recycle skb */
		++dev->estats.rx_dropped_oom;
		emac_recycle_rx_skb(dev, slot, 0);
		goto next;
	}

	if (received) {
		DBG2("%d: rx %d BDs" NL, dev->def->index, received);
		dev->rx_slot = slot;
	}

	if (unlikely(budget && dev->commac.rx_stopped)) {
		struct ocp_func_emac_data *emacdata = dev->def->additions;

		barrier();
		if (!(dev->rx_desc[slot].ctrl & MAL_RX_CTRL_EMPTY)) {
			DBG2("%d: rx restart" NL, dev->def->index);
			received = 0;
			goto again;
		}

		if (dev->rx_sg_skb) {
			DBG2("%d: dropping partial rx packet" NL,
			     dev->def->index);
			++dev->estats.rx_dropped_error;
			dev_kfree_skb(dev->rx_sg_skb);
			dev->rx_sg_skb = NULL;
		}

		dev->commac.rx_stopped = 0;
		mal_enable_rx_channel(dev->mal, emacdata->mal_rx_chan);
		emac_rx_enable(dev);
		dev->rx_slot = 0;
	}
	return received;
}

/* BHs disabled */
static int emac_peek_rx(void *param)
{
	struct ocp_enet_private *dev = param;
	return !(dev->rx_desc[dev->rx_slot].ctrl & MAL_RX_CTRL_EMPTY);
}

/* BHs disabled */
static int emac_peek_rx_sg(void *param)
{
	struct ocp_enet_private *dev = param;
	int slot = dev->rx_slot;
	while (1) {
		u16 ctrl = dev->rx_desc[slot].ctrl;
		if (ctrl & MAL_RX_CTRL_EMPTY)
			return 0;
		else if (ctrl & MAL_RX_CTRL_LAST)
			return 1;

		slot = (slot + 1) % NUM_RX_BUFF;

		/* I'm just being paranoid here :) */
		if (unlikely(slot == dev->rx_slot))
			return 0;
	}
}

/* Hard IRQ */
static void emac_rxde(void *param)
{
	struct ocp_enet_private *dev = param;
	++dev->estats.rx_stopped;
	emac_rx_disable_async(dev);
}

/* Hard IRQ */
static irqreturn_t emac_irq(int irq, void *dev_instance, struct pt_regs *regs)
{
	struct ocp_enet_private *dev = dev_instance;
	struct emac_regs *p = dev->emacp;
	struct ibm_emac_error_stats *st = &dev->estats;

	u32 isr = in_be32(&p->isr);
	out_be32(&p->isr, isr);

	DBG("%d: isr = %08x" NL, dev->def->index, isr);

	if (isr & EMAC_ISR_TXPE)
		++st->tx_parity;
	if (isr & EMAC_ISR_RXPE)
		++st->rx_parity;
	if (isr & EMAC_ISR_TXUE)
		++st->tx_underrun;
	if (isr & EMAC_ISR_RXOE)
		++st->rx_fifo_overrun;
	if (isr & EMAC_ISR_OVR)
		++st->rx_overrun;
	if (isr & EMAC_ISR_BP)
		++st->rx_bad_packet;
	if (isr & EMAC_ISR_RP)
		++st->rx_runt_packet;
	if (isr & EMAC_ISR_SE)
		++st->rx_short_event;
	if (isr & EMAC_ISR_ALE)
		++st->rx_alignment_error;
	if (isr & EMAC_ISR_BFCS)
		++st->rx_bad_fcs;
	if (isr & EMAC_ISR_PTLE)
		++st->rx_packet_too_long;
	if (isr & EMAC_ISR_ORE)
		++st->rx_out_of_range;
	if (isr & EMAC_ISR_IRE)
		++st->rx_in_range;
	if (isr & EMAC_ISR_SQE)
		++st->tx_sqe;
	if (isr & EMAC_ISR_TE)
		++st->tx_errors;

	return IRQ_HANDLED;
}

static struct net_device_stats *emac_stats(struct net_device *ndev)
{
	struct ocp_enet_private *dev = ndev->priv;
	struct ibm_emac_stats *st = &dev->stats;
	struct ibm_emac_error_stats *est = &dev->estats;
	struct net_device_stats *nst = &dev->nstats;

	DBG2("%d: stats" NL, dev->def->index);

	/* Compute "legacy" statistics */
	local_irq_disable();
	nst->rx_packets = (unsigned long)st->rx_packets;
	nst->rx_bytes = (unsigned long)st->rx_bytes;
	nst->tx_packets = (unsigned long)st->tx_packets;
	nst->tx_bytes = (unsigned long)st->tx_bytes;
	nst->rx_dropped = (unsigned long)(est->rx_dropped_oom +
					  est->rx_dropped_error +
					  est->rx_dropped_resize +
					  est->rx_dropped_mtu);
	nst->tx_dropped = (unsigned long)est->tx_dropped;

	nst->rx_errors = (unsigned long)est->rx_bd_errors;
	nst->rx_fifo_errors = (unsigned long)(est->rx_bd_overrun +
					      est->rx_fifo_overrun +
					      est->rx_overrun);
	nst->rx_frame_errors = (unsigned long)(est->rx_bd_alignment_error +
					       est->rx_alignment_error);
	nst->rx_crc_errors = (unsigned long)(est->rx_bd_bad_fcs +
					     est->rx_bad_fcs);
	nst->rx_length_errors = (unsigned long)(est->rx_bd_runt_packet +
						est->rx_bd_short_event +
						est->rx_bd_packet_too_long +
						est->rx_bd_out_of_range +
						est->rx_bd_in_range +
						est->rx_runt_packet +
						est->rx_short_event +
						est->rx_packet_too_long +
						est->rx_out_of_range +
						est->rx_in_range);

	nst->tx_errors = (unsigned long)(est->tx_bd_errors + est->tx_errors);
	nst->tx_fifo_errors = (unsigned long)(est->tx_bd_underrun +
					      est->tx_underrun);
	nst->tx_carrier_errors = (unsigned long)est->tx_bd_carrier_loss;
	nst->collisions = (unsigned long)(est->tx_bd_excessive_deferral +
					  est->tx_bd_excessive_collisions +
					  est->tx_bd_late_collision +
					  est->tx_bd_multple_collisions);
	local_irq_enable();
	return nst;
}

static void emac_remove(struct ocp_device *ocpdev)
{
	struct ocp_enet_private *dev = ocp_get_drvdata(ocpdev);

	DBG("%d: remove" NL, dev->def->index);

	ocp_set_drvdata(ocpdev, 0);
	unregister_netdev(dev->ndev);

	tah_fini(dev->tah_dev);
	rgmii_fini(dev->rgmii_dev, dev->rgmii_input);
	zmii_fini(dev->zmii_dev, dev->zmii_input);

	emac_dbg_register(dev->def->index, 0);

	mal_unregister_commac(dev->mal, &dev->commac);
	iounmap((void *)dev->emacp);
	kfree(dev->ndev);
}

static struct mal_commac_ops emac_commac_ops = {
	.poll_tx = &emac_poll_tx,
	.poll_rx = &emac_poll_rx,
	.peek_rx = &emac_peek_rx,
	.rxde = &emac_rxde,
};

static struct mal_commac_ops emac_commac_sg_ops = {
	.poll_tx = &emac_poll_tx,
	.poll_rx = &emac_poll_rx,
	.peek_rx = &emac_peek_rx_sg,
	.rxde = &emac_rxde,
};

/* Ethtool support */
static int emac_ethtool_get_settings(struct net_device *ndev,
				     struct ethtool_cmd *cmd)
{
	struct ocp_enet_private *dev = ndev->priv;

	cmd->supported = dev->phy.features;
	cmd->port = PORT_MII;
	cmd->phy_address = dev->phy.address;
	cmd->transceiver =
	    dev->phy.address >= 0 ? XCVR_EXTERNAL : XCVR_INTERNAL;

	local_bh_disable();
	cmd->advertising = dev->phy.advertising;
	cmd->autoneg = dev->phy.autoneg;
	cmd->speed = dev->phy.speed;
	cmd->duplex = dev->phy.duplex;
	local_bh_enable();

	return 0;
}

static int emac_ethtool_set_settings(struct net_device *ndev,
				     struct ethtool_cmd *cmd)
{
	struct ocp_enet_private *dev = ndev->priv;
	u32 f = dev->phy.features;

	DBG("%d: set_settings(%d, %d, %d, 0x%08x)" NL, dev->def->index,
	    cmd->autoneg, cmd->speed, cmd->duplex, cmd->advertising);

	/* Basic sanity checks */
	if (dev->phy.address < 0)
		return -EOPNOTSUPP;
	if (cmd->autoneg != AUTONEG_ENABLE && cmd->autoneg != AUTONEG_DISABLE)
		return -EINVAL;
	if (cmd->autoneg == AUTONEG_ENABLE && cmd->advertising == 0)
		return -EINVAL;
	if (cmd->duplex != DUPLEX_HALF && cmd->duplex != DUPLEX_FULL)
		return -EINVAL;

	if (cmd->autoneg == AUTONEG_DISABLE) {
		switch (cmd->speed) {
		case SPEED_10:
			if (cmd->duplex == DUPLEX_HALF
			    && !(f & SUPPORTED_10baseT_Half))
				return -EINVAL;
			if (cmd->duplex == DUPLEX_FULL
			    && !(f & SUPPORTED_10baseT_Full))
				return -EINVAL;
			break;
		case SPEED_100:
			if (cmd->duplex == DUPLEX_HALF
			    && !(f & SUPPORTED_100baseT_Half))
				return -EINVAL;