myri_sbus.c

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	skb->mac.raw = (((unsigned char *)skb->data) + MYRI_PAD_LEN);
	skb_pull(skb, dev->hard_header_len);
	eth = skb->mac.ethernet;
	
#ifdef DEBUG_HEADER
	DHDR(("myri_type_trans: "));
	dump_ehdr(eth);
#endif
	if (*eth->h_dest & 1) {
		if (memcmp(eth->h_dest, dev->broadcast, ETH_ALEN)==0)
			skb->pkt_type = PACKET_BROADCAST;
		else
			skb->pkt_type = PACKET_MULTICAST;
	} else if (dev->flags & (IFF_PROMISC|IFF_ALLMULTI)) {
		if (memcmp(eth->h_dest, dev->dev_addr, ETH_ALEN))
			skb->pkt_type = PACKET_OTHERHOST;
	}
	
	if (ntohs(eth->h_proto) >= 1536)
		return eth->h_proto;
		
	rawp = skb->data;
	
	/* This is a magic hack to spot IPX packets. Older Novell breaks
	 * the protocol design and runs IPX over 802.3 without an 802.2 LLC
	 * layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
	 * won't work for fault tolerant netware but does for the rest.
	 */
	if (*(unsigned short *)rawp == 0xFFFF)
		return htons(ETH_P_802_3);
		
	/* Real 802.2 LLC */
	return htons(ETH_P_802_2);
}

static void myri_rx(struct myri_eth *mp, struct net_device *dev)
{
	struct recvq *rq	= mp->rq;
	struct recvq *rqa	= mp->rqack;
	int entry		= sbus_readl(&rqa->head);
	int limit		= sbus_readl(&rqa->tail);
	int drops;

	DRX(("entry[%d] limit[%d] ", entry, limit));
	if (entry == limit)
		return;
	drops = 0;
	DRX(("\n"));
	while (entry != limit) {
		struct myri_rxd *rxdack = &rqa->myri_rxd[entry];
		u32 csum		= sbus_readl(&rxdack->csum);
		int len			= sbus_readl(&rxdack->myri_scatters[0].len);
		int index		= sbus_readl(&rxdack->ctx);
		struct myri_rxd *rxd	= &rq->myri_rxd[rq->tail];
		struct sk_buff *skb	= mp->rx_skbs[index];

		/* Ack it. */
		sbus_writel(NEXT_RX(entry), &rqa->head);

		/* Check for errors. */
		DRX(("rxd[%d]: %p len[%d] csum[%08x] ", entry, rxd, len, csum));
		sbus_dma_sync_single(mp->myri_sdev,
				     sbus_readl(&rxd->myri_scatters[0].addr),
				     RX_ALLOC_SIZE, SBUS_DMA_FROMDEVICE);
		if (len < (ETH_HLEN + MYRI_PAD_LEN) || (skb->data[0] != MYRI_PAD_LEN)) {
			DRX(("ERROR["));
			mp->enet_stats.rx_errors++;
			if (len < (ETH_HLEN + MYRI_PAD_LEN)) {
				DRX(("BAD_LENGTH] "));
				mp->enet_stats.rx_length_errors++;
			} else {
				DRX(("NO_PADDING] "));
				mp->enet_stats.rx_frame_errors++;
			}

			/* Return it to the LANAI. */
	drop_it:
			drops++;
			DRX(("DROP "));
			mp->enet_stats.rx_dropped++;
			sbus_writel(RX_ALLOC_SIZE, &rxd->myri_scatters[0].len);
			sbus_writel(index, &rxd->ctx);
			sbus_writel(1, &rxd->num_sg);
			sbus_writel(NEXT_RX(sbus_readl(&rq->tail)), &rq->tail);
			goto next;
		}

		DRX(("len[%d] ", len));
		if (len > RX_COPY_THRESHOLD) {
			struct sk_buff *new_skb;
			u32 dma_addr;

			DRX(("BIGBUFF "));
			new_skb = myri_alloc_skb(RX_ALLOC_SIZE, GFP_ATOMIC);
			if (new_skb == NULL) {
				DRX(("skb_alloc(FAILED) "));
				goto drop_it;
			}
			sbus_unmap_single(mp->myri_sdev,
					  sbus_readl(&rxd->myri_scatters[0].addr),
					  RX_ALLOC_SIZE,
					  SBUS_DMA_FROMDEVICE);
			mp->rx_skbs[index] = new_skb;
			new_skb->dev = dev;
			skb_put(new_skb, RX_ALLOC_SIZE);
			dma_addr = sbus_map_single(mp->myri_sdev,
						   new_skb->data,
						   RX_ALLOC_SIZE,
						   SBUS_DMA_FROMDEVICE);
			sbus_writel(dma_addr, &rxd->myri_scatters[0].addr);
			sbus_writel(RX_ALLOC_SIZE, &rxd->myri_scatters[0].len);
			sbus_writel(index, &rxd->ctx);
			sbus_writel(1, &rxd->num_sg);
			sbus_writel(NEXT_RX(sbus_readl(&rq->tail)), &rq->tail);

			/* Trim the original skb for the netif. */
			DRX(("trim(%d) ", len));
			skb_trim(skb, len);
		} else {
			struct sk_buff *copy_skb = dev_alloc_skb(len);

			DRX(("SMALLBUFF "));
			if (copy_skb == NULL) {
				DRX(("dev_alloc_skb(FAILED) "));
				goto drop_it;
			}
			/* DMA sync already done above. */
			copy_skb->dev = dev;
			DRX(("resv_and_put "));
			skb_put(copy_skb, len);
			memcpy(copy_skb->data, skb->data, len);

			/* Reuse original ring buffer. */
			DRX(("reuse "));
			sbus_writel(RX_ALLOC_SIZE, &rxd->myri_scatters[0].len);
			sbus_writel(index, &rxd->ctx);
			sbus_writel(1, &rxd->num_sg);
			sbus_writel(NEXT_RX(sbus_readl(&rq->tail)), &rq->tail);

			skb = copy_skb;
		}

		/* Just like the happy meal we get checksums from this card. */
		skb->csum = csum;
		skb->ip_summed = CHECKSUM_UNNECESSARY; /* XXX */

		skb->protocol = myri_type_trans(skb, dev);
		DRX(("prot[%04x] netif_rx ", skb->protocol));
		netif_rx(skb);

		mp->enet_stats.rx_packets++;
	next:
		DRX(("NEXT\n"));
		entry = NEXT_RX(entry);
	}
}

static void myri_interrupt(int irq, void *dev_id, struct pt_regs *regs)
{
	struct net_device *dev		= (struct net_device *) dev_id;
	struct myri_eth *mp		= (struct myri_eth *) dev->priv;
	unsigned long lregs		= mp->lregs;
	struct myri_channel *chan	= &mp->shmem->channel;
	u32 status;

	status = sbus_readl(lregs + LANAI_ISTAT);
	DIRQ(("myri_interrupt: status[%08x] ", status));
	if (status & ISTAT_HOST) {
		u32 softstate;

		DIRQ(("IRQ_DISAB "));
		myri_disable_irq(lregs, mp->cregs);
		softstate = sbus_readl(&chan->state);
		DIRQ(("state[%08x] ", softstate));
		if (softstate != STATE_READY) {
			DIRQ(("myri_not_so_happy "));
			myri_is_not_so_happy(mp);
		}
		DIRQ(("\nmyri_rx: "));
		myri_rx(mp, dev);
		DIRQ(("\nistat=ISTAT_HOST "));
		sbus_writel(ISTAT_HOST, lregs + LANAI_ISTAT);
		DIRQ(("IRQ_ENAB "));
		myri_enable_irq(lregs, mp->cregs);
	}
	DIRQ(("\n"));
}

static int myri_open(struct net_device *dev)
{
	struct myri_eth *mp = (struct myri_eth *) dev->priv;

	return myri_init(mp, in_interrupt());
}

static int myri_close(struct net_device *dev)
{
	struct myri_eth *mp = (struct myri_eth *) dev->priv;

	myri_clean_rings(mp);
	return 0;
}

static void myri_tx_timeout(struct net_device *dev)
{
	struct myri_eth *mp = (struct myri_eth *) dev->priv;

	printk(KERN_ERR "%s: transmit timed out, resetting\n", dev->name);

	mp->enet_stats.tx_errors++;
	myri_init(mp, 0);
	netif_start_queue(dev);
}

static int myri_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
	struct myri_eth *mp = (struct myri_eth *) dev->priv;
	struct sendq *sq = mp->sq;
	struct myri_txd *txd;
	unsigned long flags;
	unsigned int head, tail;
	int len, entry;
	u32 dma_addr;

	DTX(("myri_start_xmit: "));

	myri_tx(mp, dev);

	netif_stop_queue(dev);

	/* This is just to prevent multiple PIO reads for TX_BUFFS_AVAIL. */
	head = sbus_readl(&sq->head);
	tail = sbus_readl(&sq->tail);

	if (!TX_BUFFS_AVAIL(head, tail)) {
		DTX(("no buffs available, returning 1\n"));
		return 1;
	}

	save_and_cli(flags);

	DHDR(("xmit[skbdata(%p)]\n", skb->data));
#ifdef DEBUG_HEADER
	dump_ehdr_and_myripad(((unsigned char *) skb->data));
#endif

	/* XXX Maybe this can go as well. */
	len = skb->len;
	if (len & 3) {
		DTX(("len&3 "));
		len = (len + 4) & (~3);
	}

	entry = sbus_readl(&sq->tail);

	txd = &sq->myri_txd[entry];
	mp->tx_skbs[entry] = skb;

	/* Must do this before we sbus map it. */
	if (skb->data[MYRI_PAD_LEN] & 0x1) {
		sbus_writew(0xffff, &txd->addr[0]);
		sbus_writew(0xffff, &txd->addr[1]);
		sbus_writew(0xffff, &txd->addr[2]);
		sbus_writew(0xffff, &txd->addr[3]);
	} else {
		sbus_writew(0xffff, &txd->addr[0]);
		sbus_writew((skb->data[0] << 8) | skb->data[1], &txd->addr[1]);
		sbus_writew((skb->data[2] << 8) | skb->data[3], &txd->addr[2]);
		sbus_writew((skb->data[4] << 8) | skb->data[5], &txd->addr[3]);
	}

	dma_addr = sbus_map_single(mp->myri_sdev, skb->data, len, SBUS_DMA_TODEVICE);
	sbus_writel(dma_addr, &txd->myri_gathers[0].addr);
	sbus_writel(len, &txd->myri_gathers[0].len);
	sbus_writel(1, &txd->num_sg);
	sbus_writel(KERNEL_CHANNEL, &txd->chan);
	sbus_writel(len, &txd->len);
	sbus_writel((u32)-1, &txd->csum_off);
	sbus_writel(0, &txd->csum_field);

	sbus_writel(NEXT_TX(entry), &sq->tail);
	DTX(("BangTheChip "));
	bang_the_chip(mp);

	DTX(("tbusy=0, returning 0\n"));
	netif_start_queue(dev);
	restore_flags(flags);
	return 0;
}

/* Create the MyriNet MAC header for an arbitrary protocol layer 
 *
 * saddr=NULL	means use device source address
 * daddr=NULL	means leave destination address (eg unresolved arp)
 */
static int myri_header(struct sk_buff *skb, struct net_device *dev, unsigned short type,
		       void *daddr, void *saddr, unsigned len)
{
	struct ethhdr *eth = (struct ethhdr *) skb_push(skb, ETH_HLEN);
	unsigned char *pad = (unsigned char *) skb_push(skb, MYRI_PAD_LEN);

#ifdef DEBUG_HEADER
	DHDR(("myri_header: pad[%02x,%02x] ", pad[0], pad[1]));
	dump_ehdr(eth);
#endif

	/* Set the MyriNET padding identifier. */
	pad[0] = MYRI_PAD_LEN;
	pad[1] = 0xab;

	/* Set the protocol type. For a packet of type ETH_P_802_3 we put the length
	 * in here instead. It is up to the 802.2 layer to carry protocol information.
	 */
	if (type != ETH_P_802_3) 
		eth->h_proto = htons(type);
	else
		eth->h_proto = htons(len);

	/* Set the source hardware address. */
	if (saddr)
		memcpy(eth->h_source, saddr, dev->addr_len);
	else
		memcpy(eth->h_source, dev->dev_addr, dev->addr_len);

	/* Anyway, the loopback-device should never use this function... */
	if (dev->flags & IFF_LOOPBACK) {
		int i;
		for (i = 0; i < dev->addr_len; i++)
			eth->h_dest[i] = 0;
		return(dev->hard_header_len);
	}
	
	if (daddr) {
		memcpy(eth->h_dest, daddr, dev->addr_len);
		return dev->hard_header_len;
	}
	return -dev->hard_header_len;
}

/* Rebuild the MyriNet MAC header. This is called after an ARP
 * (or in future other address resolution) has completed on this
 * sk_buff. We now let ARP fill in the other fields.
 */
static int myri_rebuild_header(struct sk_buff *skb)
{
	unsigned char *pad = (unsigned char *) skb->data;
	struct ethhdr *eth = (struct ethhdr *) (pad + MYRI_PAD_LEN);
	struct net_device *dev = skb->dev;

#ifdef DEBUG_HEADER
	DHDR(("myri_rebuild_header: pad[%02x,%02x] ", pad[0], pad[1]));
	dump_ehdr(eth);
#endif

	/* Refill MyriNet padding identifiers, this is just being anal. */
	pad[0] = MYRI_PAD_LEN;
	pad[1] = 0xab;

	switch (eth->h_proto)
	{
#ifdef CONFIG_INET
	case __constant_htons(ETH_P_IP):
 		return arp_find(eth->h_dest, skb);
#endif

	default:
		printk(KERN_DEBUG 
		       "%s: unable to resolve type %X addresses.\n", 
		       dev->name, (int)eth->h_proto);
		
		memcpy(eth->h_source, dev->dev_addr, dev->addr_len);
		return 0;
		break;
	}

	return 0;	
}

int myri_header_cache(struct neighbour *neigh, struct hh_cache *hh)
{
	unsigned short type = hh->hh_type;
	unsigned char *pad = (unsigned char *) hh->hh_data;
	struct ethhdr *eth = (struct ethhdr *) (pad + MYRI_PAD_LEN);