text: /* myri_sbus.h: MyriCOM MyriNET SBUS card driver.
   *
   * Copyright (C) 1996, 1999 David S. Miller (davem@redhat.com)
   */
  
  static char version[] =
          "myri_sbus.c:v1.9 12/Sep/99 David S. Miller (davem@redhat.com)\n";
  
  #include <linux/module.h>
  
  #include <linux/config.h>
  #include <linux/kernel.h>
  #include <linux/sched.h>
  #include <linux/types.h>
  #include <linux/fcntl.h>
  #include <linux/interrupt.h>
  #include <linux/ptrace.h>
  #include <linux/ioport.h>
  #include <linux/in.h>
  #include <linux/slab.h>
  #include <linux/string.h>
  #include <linux/delay.h>
  #include <linux/init.h>
  
  #include <asm/system.h>
  #include <asm/bitops.h>
  #include <asm/io.h>
  #include <asm/dma.h>
  #include <linux/errno.h>
  #include <asm/byteorder.h>
  
  #include <asm/idprom.h>
  #include <asm/sbus.h>
  #include <asm/openprom.h>
  #include <asm/oplib.h>
  #include <asm/auxio.h>
  #include <asm/pgtable.h>
  #include <asm/irq.h>
  
  #include <linux/netdevice.h>
  #include <linux/etherdevice.h>
  #include <linux/skbuff.h>
  
  #include <net/dst.h>
  #include <net/arp.h>
  #include <net/sock.h>
  #include <net/ipv6.h>
  
  #include <asm/checksum.h>
  
  #include "myri_sbus.h"
  
  #include "myri_code.h"
  
  /* #define DEBUG_DETECT */
  /* #define DEBUG_IRQ */
  /* #define DEBUG_TRANSMIT */
  /* #define DEBUG_RECEIVE */
  /* #define DEBUG_HEADER */
  
  #ifdef DEBUG_DETECT
  #define DET(x)   printk x
  #else
  #define DET(x)
  #endif
  
  #ifdef DEBUG_IRQ
  #define DIRQ(x)  printk x
  #else
  #define DIRQ(x)
  #endif
  
  #ifdef DEBUG_TRANSMIT
  #define DTX(x)  printk x
  #else
  #define DTX(x)
  #endif
  
  #ifdef DEBUG_RECEIVE
  #define DRX(x)  printk x
  #else
  #define DRX(x)
  #endif
  
  #ifdef DEBUG_HEADER
  #define DHDR(x) printk x
  #else
  #define DHDR(x)
  #endif
  
  #ifdef MODULE
  static struct myri_eth *root_myri_dev;
  #endif
  
  static void myri_reset_off(unsigned long lp, unsigned long cregs)
  {
  	/* Clear IRQ mask. */
  	sbus_writel(0, lp + LANAI_EIMASK);
  
  	/* Turn RESET function off. */
  	sbus_writel(CONTROL_ROFF, cregs + MYRICTRL_CTRL);
  }
  
  static void myri_reset_on(unsigned long cregs)
  {
  	/* Enable RESET function. */
  	sbus_writel(CONTROL_RON, cregs + MYRICTRL_CTRL);
  
  	/* Disable IRQ's. */
  	sbus_writel(CONTROL_DIRQ, cregs + MYRICTRL_CTRL);
  }
  
  static void myri_disable_irq(unsigned long lp, unsigned long cregs)
  {
  	sbus_writel(CONTROL_DIRQ, cregs + MYRICTRL_CTRL);
  	sbus_writel(0, lp + LANAI_EIMASK);
  	sbus_writel(ISTAT_HOST, lp + LANAI_ISTAT);
  }
  
  static void myri_enable_irq(unsigned long lp, unsigned long cregs)
  {
  	sbus_writel(CONTROL_EIRQ, cregs + MYRICTRL_CTRL);
  	sbus_writel(ISTAT_HOST, lp + LANAI_EIMASK);
  }
  
  static inline void bang_the_chip(struct myri_eth *mp)
  {
  	struct myri_shmem *shmem	= mp->shmem;
  	unsigned long cregs		= mp->cregs;
  
  	sbus_writel(1, &shmem->send);
  	sbus_writel(CONTROL_WON, cregs + MYRICTRL_CTRL);
  }
  
  static int myri_do_handshake(struct myri_eth *mp)
  {
  	struct myri_shmem *shmem	= mp->shmem;
  	unsigned long cregs = mp->cregs;
  	struct myri_channel *chan	= &shmem->channel;
  	int tick 			= 0;
  
  	DET(("myri_do_handshake: "));
  	if (sbus_readl(&chan->state) == STATE_READY) {
  		DET(("Already STATE_READY, failed.\n"));
  		return -1;	/* We're hosed... */
  	}
  
  	myri_disable_irq(mp->lregs, cregs);
  
  	while (tick++ <= 25) {
  		u32 softstate;
  
  		/* Wake it up. */
  		DET(("shakedown, CONTROL_WON, "));
  		sbus_writel(1, &shmem->shakedown);
  		sbus_writel(CONTROL_WON, cregs + MYRICTRL_CTRL);
  
  		softstate = sbus_readl(&chan->state);
  		DET(("chanstate[%08x] ", softstate));
  		if (softstate == STATE_READY) {
  			DET(("wakeup successful, "));
  			break;
  		}
  
  		if (softstate != STATE_WFN) {
  			DET(("not WFN setting that, "));
  			sbus_writel(STATE_WFN, &chan->state);
  		}
  
  		udelay(20);
  	}
  
  	myri_enable_irq(mp->lregs, cregs);
  
  	if (tick > 25) {
  		DET(("25 ticks we lose, failure.\n"));
  		return -1;
  	}
  	DET(("success\n"));
  	return 0;
  }
  
  static int myri_load_lanai(struct myri_eth *mp)
  {
  	struct net_device	*dev = mp->dev;
  	struct myri_shmem	*shmem = mp->shmem;
  	unsigned char		*rptr;
  	int 			i;
  
  	myri_disable_irq(mp->lregs, mp->cregs);
  	myri_reset_on(mp->cregs);
  
  	rptr = (unsigned char *) mp->lanai;
  	for (i = 0; i < mp->eeprom.ramsz; i++)
  		sbus_writeb(0, &rptr[i]);
  
  	if (mp->eeprom.cpuvers >= CPUVERS_3_0)
  		sbus_writel(mp->eeprom.cval, mp->lregs + LANAI_CVAL);
  
  	/* Load executable code. */
  	for (i = 0; i < sizeof(lanai4_code); i++)
  		sbus_writeb(lanai4_code[i], &rptr[(lanai4_code_off * 2) + i]);
  
  	/* Load data segment. */
  	for (i = 0; i < sizeof(lanai4_data); i++)
  		sbus_writeb(lanai4_data[i], &rptr[(lanai4_data_off * 2) + i]);
  
  	/* Set device address. */
  	sbus_writeb(0, &shmem->addr[0]);
  	sbus_writeb(0, &shmem->addr[1]);
  	for (i = 0; i < 6; i++)
  		sbus_writeb(dev->dev_addr[i],
  			    &shmem->addr[i + 2]);
  
  	/* Set SBUS bursts and interrupt mask. */
  	sbus_writel(((mp->myri_bursts & 0xf8) >> 3), &shmem->burst);
  	sbus_writel(SHMEM_IMASK_RX, &shmem->imask);
  
  	/* Release the LANAI. */
  	myri_disable_irq(mp->lregs, mp->cregs);
  	myri_reset_off(mp->lregs, mp->cregs);
  	myri_disable_irq(mp->lregs, mp->cregs);
  
  	/* Wait for the reset to complete. */
  	for (i = 0; i < 5000; i++) {
  		if (sbus_readl(&shmem->channel.state) != STATE_READY)
  			break;
  		else
  			udelay(10);
  	}
  
  	if (i == 5000)
  		printk(KERN_ERR "myricom: Chip would not reset after firmware load.\n");
  
  	i = myri_do_handshake(mp);
  	if (i)
  		printk(KERN_ERR "myricom: Handshake with LANAI failed.\n");
  
  	if (mp->eeprom.cpuvers == CPUVERS_4_0)
  		sbus_writel(0, mp->lregs + LANAI_VERS);
  
  	return i;
  }
  
  static void myri_clean_rings(struct myri_eth *mp)
  {
  	struct sendq *sq = mp->sq;
  	struct recvq *rq = mp->rq;
  	int i;
  
  	sbus_writel(0, &rq->tail);
  	sbus_writel(0, &rq->head);
  	for (i = 0; i < (RX_RING_SIZE+1); i++) {
  		if (mp->rx_skbs[i] != NULL) {
  			struct myri_rxd *rxd = &rq->myri_rxd[i];
  			u32 dma_addr;
  
  			dma_addr = sbus_readl(&rxd->myri_scatters[0].addr);
  			sbus_unmap_single(mp->myri_sdev, dma_addr, RX_ALLOC_SIZE, SBUS_DMA_FROMDEVICE);
  			dev_kfree_skb(mp->rx_skbs[i]);
  			mp->rx_skbs[i] = NULL;
  		}
  	}
  
  	mp->tx_old = 0;
  	sbus_writel(0, &sq->tail);
  	sbus_writel(0, &sq->head);
  	for (i = 0; i < TX_RING_SIZE; i++) {
  		if (mp->tx_skbs[i] != NULL) {
  			struct sk_buff *skb = mp->tx_skbs[i];
  			struct myri_txd *txd = &sq->myri_txd[i];
  			u32 dma_addr;
  
  			dma_addr = sbus_readl(&txd->myri_gathers[0].addr);
  			sbus_unmap_single(mp->myri_sdev, dma_addr, (skb->len + 3) & ~3, SBUS_DMA_TODEVICE);
  			dev_kfree_skb(mp->tx_skbs[i]);
  			mp->tx_skbs[i] = NULL;
  		}
  	}
  }
  
  static void myri_init_rings(struct myri_eth *mp, int from_irq)
  {
  	struct recvq *rq = mp->rq;
  	struct myri_rxd *rxd = &rq->myri_rxd[0];
  	struct net_device *dev = mp->dev;
  	int gfp_flags = GFP_KERNEL;
  	int i;
  
  	if (from_irq || in_interrupt())
  		gfp_flags = GFP_ATOMIC;
  
  	myri_clean_rings(mp);
  	for (i = 0; i < RX_RING_SIZE; i++) {
  		struct sk_buff *skb = myri_alloc_skb(RX_ALLOC_SIZE, gfp_flags);
  		u32 dma_addr;
  
  		if (!skb)
  			continue;
  		mp->rx_skbs[i] = skb;
  		skb->dev = dev;
  		skb_put(skb, RX_ALLOC_SIZE);
  
  		dma_addr = sbus_map_single(mp->myri_sdev, skb->data, RX_ALLOC_SIZE, SBUS_DMA_FROMDEVICE);
  		sbus_writel(dma_addr, &rxd[i].myri_scatters[0].addr);
  		sbus_writel(RX_ALLOC_SIZE, &rxd[i].myri_scatters[0].len);
  		sbus_writel(i, &rxd[i].ctx);
  		sbus_writel(1, &rxd[i].num_sg);
  	}
  	sbus_writel(0, &rq->head);
  	sbus_writel(RX_RING_SIZE, &rq->tail);
  }
  
  static int myri_init(struct myri_eth *mp, int from_irq)
  {
  	myri_init_rings(mp, from_irq);
  	return 0;
  }
  
  static void myri_is_not_so_happy(struct myri_eth *mp)
  {
  }
  
  #ifdef DEBUG_HEADER
  static void dump_ehdr(struct ethhdr *ehdr)
  {
  	printk("ehdr[h_dst(%02x:%02x:%02x:%02x:%02x:%02x)"
  	       "h_source(%02x:%02x:%02x:%02x:%02x:%02x)h_proto(%04x)]\n",
  	       ehdr->h_dest[0], ehdr->h_dest[1], ehdr->h_dest[2],
  	       ehdr->h_dest[3], ehdr->h_dest[4], ehdr->h_dest[4],
  	       ehdr->h_source[0], ehdr->h_source[1], ehdr->h_source[2],
  	       ehdr->h_source[3], ehdr->h_source[4], ehdr->h_source[4],
  	       ehdr->h_proto);
  }
  
  static void dump_ehdr_and_myripad(unsigned char *stuff)
  {
  	struct ethhdr *ehdr = (struct ethhdr *) (stuff + 2);
  
  	printk("pad[%02x:%02x]", stuff[0], stuff[1]);
  	printk("ehdr[h_dst(%02x:%02x:%02x:%02x:%02x:%02x)"
  	       "h_source(%02x:%02x:%02x:%02x:%02x:%02x)h_proto(%04x)]\n",
  	       ehdr->h_dest[0], ehdr->h_dest[1], ehdr->h_dest[2],
  	       ehdr->h_dest[3], ehdr->h_dest[4], ehdr->h_dest[4],
  	       ehdr->h_source[0], ehdr->h_source[1], ehdr->h_source[2],
  	       ehdr->h_source[3], ehdr->h_source[4], ehdr->h_source[4],
  	       ehdr->h_proto);
  }
  #endif
  
  static void myri_tx(struct myri_eth *mp, struct net_device *dev)
  {
  	struct sendq *sq	= mp->sq;
  	int entry		= mp->tx_old;
  	int limit		= sbus_readl(&sq->head);
  
  	DTX(("entry[%d] limit[%d] ", entry, limit));
  	if (entry == limit)
  		return;
  	while (entry != limit) {
  		struct sk_buff *skb = mp->tx_skbs[entry];
  		u32 dma_addr;
  
  		DTX(("SKB[%d] ", entry));
  		dma_addr = sbus_readl(&sq->myri_txd[entry].myri_gathers[0].addr);
  		sbus_unmap_single(mp->myri_sdev, dma_addr, skb->len, SBUS_DMA_TODEVICE);
  		dev_kfree_skb(skb);
  		mp->tx_skbs[entry] = NULL;
  		mp->enet_stats.tx_packets++;
  		entry = NEXT_TX(entry);
  	}
  	mp->tx_old = entry;
  }
  
  /* Determine the packet's protocol ID. The rule here is that we 
   * assume 802.3 if the type field is short enough to be a length.
   * This is normal practice and works for any 'now in use' protocol.
   */
  static unsigned short myri_type_trans(struct sk_buff *skb, struct net_device *dev)
  {
  	struct ethhdr *eth;
  	unsigned char *rawp;
  	
  	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; 
  
  		skb->protocol = myri_type_trans(skb, dev);
  		DRX(("prot[%04x] netif_rx ", skb->protocol));
  		netif_rx(skb);
  
  		dev->last_rx = jiffies;
  		mp->enet_stats.rx_packets++;
  		mp->enet_stats.rx_bytes += len;
  	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_wake_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
  
  	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);
  	struct net_device *dev = neigh->dev;
  
  	if (type == __constant_htons(ETH_P_802_3))
  		return -1;
  
  	/* Refill MyriNet padding identifiers, this is just being anal. */
  	pad[0] = MYRI_PAD_LEN;
  	pad[1] = 0xab;
  
  	eth->h_proto = type;
  	memcpy(eth->h_source, dev->dev_addr, dev->addr_len);
  	memcpy(eth->h_dest, neigh->ha, dev->addr_len);
  	hh->hh_len = 16;
  	return 0;
  }
  
  
  /* Called by Address Resolution module to notify changes in address. */
  void myri_header_cache_update(struct hh_cache *hh, struct net_device *dev, unsigned char * haddr)
  {
  	memcpy(((u8*)hh->hh_data) + 2, haddr, dev->addr_len);
  }
  
  static int myri_change_mtu(struct net_device *dev, int new_mtu)
  {
  	if ((new_mtu < (ETH_HLEN + MYRI_PAD_LEN)) || (new_mtu > MYRINET_MTU))
  		return -EINVAL;
  	dev->mtu = new_mtu;
  	return 0;
  }
  
  static struct net_device_stats *myri_get_stats(struct net_device *dev)
  { return &(((struct myri_eth *)dev->priv)->enet_stats); }
  
  static void myri_set_multicast(struct net_device *dev)
  {
  	/* Do nothing, all MyriCOM nodes transmit multicast frames
  	 * as broadcast packets...
  	 */
  }
  
  static inline void set_boardid_from_idprom(struct myri_eth *mp, int num)
  {
  	mp->eeprom.id[0] = 0;
  	mp->eeprom.id[1] = idprom->id_machtype;
  	mp->eeprom.id[2] = (idprom->id_sernum >> 16) & 0xff;
  	mp->eeprom.id[3] = (idprom->id_sernum >> 8) & 0xff;
  	mp->eeprom.id[4] = (idprom->id_sernum >> 0) & 0xff;
  	mp->eeprom.id[5] = num;
  }
  
  static inline void determine_reg_space_size(struct myri_eth *mp)
  {
  	switch(mp->eeprom.cpuvers) {
  	case CPUVERS_2_3:
  	case CPUVERS_3_0:
  	case CPUVERS_3_1:
  	case CPUVERS_3_2:
  		mp->reg_size = (3 * 128 * 1024) + 4096;
  		break;
  
  	case CPUVERS_4_0:
  	case CPUVERS_4_1:
  		mp->reg_size = ((4096<<1) + mp->eeprom.ramsz);
  		break;
  
  	case CPUVERS_4_2:
  	case CPUVERS_5_0:
  	default:
  		printk("myricom: AIEEE weird cpu version %04x assuming pre4.0\n",
  		       mp->eeprom.cpuvers);
  		mp->reg_size = (3 * 128 * 1024) + 4096;
  	};
  }
  
  #ifdef DEBUG_DETECT
  static void dump_eeprom(struct myri_eth *mp)
  {
  	printk("EEPROM: clockval[%08x] cpuvers[%04x] "
  	       "id[%02x,%02x,%02x,%02x,%02x,%02x]\n",
  	       mp->eeprom.cval, mp->eeprom.cpuvers,
  	       mp->eeprom.id[0], mp->eeprom.id[1], mp->eeprom.id[2],
  	       mp->eeprom.id[3], mp->eeprom.id[4], mp->eeprom.id[5]);
  	printk("EEPROM: ramsz[%08x]\n", mp->eeprom.ramsz);
  	printk("EEPROM: fvers[%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x\n",
  	       mp->eeprom.fvers[0], mp->eeprom.fvers[1], mp->eeprom.fvers[2],
  	       mp->eeprom.fvers[3], mp->eeprom.fvers[4], mp->eeprom.fvers[5],
  	       mp->eeprom.fvers[6], mp->eeprom.fvers[7]);
  	printk("EEPROM:       %02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x\n",
  	       mp->eeprom.fvers[8], mp->eeprom.fvers[9], mp->eeprom.fvers[10],
  	       mp->eeprom.fvers[11], mp->eeprom.fvers[12], mp->eeprom.fvers[13],
  	       mp->eeprom.fvers[14], mp->eeprom.fvers[15]);
  	printk("EEPROM:       %02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x\n",
  	       mp->eeprom.fvers[16], mp->eeprom.fvers[17], mp->eeprom.fvers[18],
  	       mp->eeprom.fvers[19], mp->eeprom.fvers[20], mp->eeprom.fvers[21],
  	       mp->eeprom.fvers[22], mp->eeprom.fvers[23]);
  	printk("EEPROM:       %02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x]\n",
  	       mp->eeprom.fvers[24], mp->eeprom.fvers[25], mp->eeprom.fvers[26],
  	       mp->eeprom.fvers[27], mp->eeprom.fvers[28], mp->eeprom.fvers[29],
  	       mp->eeprom.fvers[30], mp->eeprom.fvers[31]);
  	printk("EEPROM: mvers[%02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x\n",
  	       mp->eeprom.mvers[0], mp->eeprom.mvers[1], mp->eeprom.mvers[2],
  	       mp->eeprom.mvers[3], mp->eeprom.mvers[4], mp->eeprom.mvers[5],
  	       mp->eeprom.mvers[6], mp->eeprom.mvers[7]);
  	printk("EEPROM:       %02x,%02x,%02x,%02x,%02x,%02x,%02x,%02x]\n",
  	       mp->eeprom.mvers[8], mp->eeprom.mvers[9], mp->eeprom.mvers[10],
  	       mp->eeprom.mvers[11], mp->eeprom.mvers[12], mp->eeprom.mvers[13],
  	       mp->eeprom.mvers[14], mp->eeprom.mvers[15]);
  	printk("EEPROM: dlval[%04x] brd_type[%04x] bus_type[%04x] prod_code[%04x]\n",
  	       mp->eeprom.dlval, mp->eeprom.brd_type, mp->eeprom.bus_type,
  	       mp->eeprom.prod_code);
  	printk("EEPROM: serial_num[%08x]\n", mp->eeprom.serial_num);
  }
  #endif
  
  static int __init myri_ether_init(struct net_device *dev, struct sbus_dev *sdev, int num)
  {
  	static unsigned version_printed;
  	struct myri_eth *mp;
  	unsigned char prop_buf[32];
  	int i;
  
  	DET(("myri_ether_init(%p,%p,%d):\n", dev, sdev, num));
  	dev = init_etherdev(0, sizeof(struct myri_eth));
  
  	if (!dev)
  		return -ENOMEM;
  
  	if (version_printed++ == 0)
  		printk(version);
  
  	printk("%s: MyriCOM MyriNET Ethernet ", dev->name);
  
  	mp = (struct myri_eth *) dev->priv;
  	mp->myri_sdev = sdev;
  
  	/* Clean out skb arrays. */
  	for (i = 0; i < (RX_RING_SIZE + 1); i++)
  		mp->rx_skbs[i] = NULL;
  
  	for (i = 0; i < TX_RING_SIZE; i++)
  		mp->tx_skbs[i] = NULL;
  
  	/* First check for EEPROM information. */
  	i = prom_getproperty(sdev->prom_node, "myrinet-eeprom-info",
  			     (char *)&mp->eeprom, sizeof(struct myri_eeprom));
  	DET(("prom_getprop(myrinet-eeprom-info) returns %d\n", i));
  	if (i == 0 || i == -1) {
  		/* No eeprom property, must cook up the values ourselves. */
  		DET(("No EEPROM: "));
  		mp->eeprom.bus_type = BUS_TYPE_SBUS;
  		mp->eeprom.cpuvers = prom_getintdefault(sdev->prom_node,"cpu_version",0);
  		mp->eeprom.cval = prom_getintdefault(sdev->prom_node,"clock_value",0);
  		mp->eeprom.ramsz = prom_getintdefault(sdev->prom_node,"sram_size",0);
  		DET(("cpuvers[%d] cval[%d] ramsz[%d]\n", mp->eeprom.cpuvers,
  		     mp->eeprom.cval, mp->eeprom.ramsz));
  		if (mp->eeprom.cpuvers == 0) {
  			DET(("EEPROM: cpuvers was zero, setting to %04x\n",CPUVERS_2_3));
  			mp->eeprom.cpuvers = CPUVERS_2_3;
  		}
  		if (mp->eeprom.cpuvers < CPUVERS_3_0) {
  			DET(("EEPROM: cpuvers < CPUVERS_3_0, clockval set to zero.\n"));
  			mp->eeprom.cval = 0;
  		}
  		if (mp->eeprom.ramsz == 0) {
  			DET(("EEPROM: ramsz == 0, setting to 128k\n"));
  			mp->eeprom.ramsz = (128 * 1024);
  		}
  		i = prom_getproperty(sdev->prom_node, "myrinet-board-id",
  				     &prop_buf[0], 10);
  		DET(("EEPROM: prom_getprop(myrinet-board-id) returns %d\n", i));
  		if ((i != 0) && (i != -1))
  			memcpy(&mp->eeprom.id[0], &prop_buf[0], 6);
  		else
  			set_boardid_from_idprom(mp, num);
  		i = prom_getproperty(sdev->prom_node, "fpga_version",
  				     &mp->eeprom.fvers[0], 32);
  		DET(("EEPROM: prom_getprop(fpga_version) returns %d\n", i));
  		if (i == 0 || i == -1)
  			memset(&mp->eeprom.fvers[0], 0, 32);
  
  		if (mp->eeprom.cpuvers == CPUVERS_4_1) {
  			DET(("EEPROM: cpuvers CPUVERS_4_1, "));
  			if (mp->eeprom.ramsz == (128 * 1024)) {
  				DET(("ramsize 128k, setting to 256k, "));
  				mp->eeprom.ramsz = (256 * 1024);
  			}
  			if ((mp->eeprom.cval==0x40414041)||(mp->eeprom.cval==0x90449044)){
  				DET(("changing cval from %08x to %08x ",
  				     mp->eeprom.cval, 0x50e450e4));
  				mp->eeprom.cval = 0x50e450e4;
  			}
  			DET(("\n"));
  		}
  	}
  #ifdef DEBUG_DETECT
  	dump_eeprom(mp);
  #endif
  
  	for (i = 0; i < 6; i++)
  		printk("%2.2x%c",
  		       dev->dev_addr[i] = mp->eeprom.id[i],
  		       i == 5 ? ' ' : ':');
  	printk("\n");
  
  	determine_reg_space_size(mp);
  
  	/* Map in the MyriCOM register/localram set. */
  	if (mp->eeprom.cpuvers < CPUVERS_4_0) {
  		DET(("Mapping regs for cpuvers < CPUVERS_4_0\n"));
  		mp->regs = sbus_ioremap(&sdev->resource[0], 0,
  					mp->reg_size, "MyriCOM Regs");
  		if (!mp->regs) {
  			printk("MyriCOM: Cannot map MyriCOM registers.\n");
  			goto err;
  		}
  		mp->lanai = (unsigned short *) (mp->regs + (256 * 1024));
  		mp->lanai3 = (unsigned int *) mp->lanai;
  		mp->lregs = (unsigned long) &mp->lanai[0x10000];
  	} else {
  		DET(("Mapping regs for cpuvers >= CPUVERS_4_0\n"));
  		mp->cregs = sbus_ioremap(&sdev->resource[0], 0,
  					 PAGE_SIZE, "MyriCOM Control Regs");
  		mp->lregs = sbus_ioremap(&sdev->resource[0], (256 * 1024),
  					 PAGE_SIZE, "MyriCOM LANAI Regs");
  		mp->lanai = (unsigned short *)
  			sbus_ioremap(&sdev->resource[0], (512 * 1024),
  				     mp->eeprom.ramsz, "MyriCOM SRAM");
  		mp->lanai3 = (unsigned int *) mp->lanai;
  	}
  	DET(("Registers mapped: cregs[%lx] lregs[%lx] lanai[%p] lanai3[%p]\n",
  	     mp->cregs, mp->lregs, mp->lanai, mp->lanai3));
  
  	if (mp->eeprom.cpuvers >= CPUVERS_4_0)
  		mp->shmem_base = 0xf000;
  	else
  		mp->shmem_base = 0x8000;
  
  	DET(("Shared memory base is %04x, ", mp->shmem_base));
  
  	mp->shmem = (struct myri_shmem *) &mp->lanai[mp->shmem_base];
  	DET(("shmem mapped at %p\n", mp->shmem));
  
  	mp->rqack	= &mp->shmem->channel.recvqa;
  	mp->rq		= &mp->shmem->channel.recvq;
  	mp->sq		= &mp->shmem->channel.sendq;
  
  	/* Reset the board. */
  	DET(("Resetting LANAI\n"));
  	myri_reset_off(mp->lregs, mp->cregs);
  	myri_reset_on(mp->cregs);
  
  	/* Turn IRQ's off. */
  	myri_disable_irq(mp->lregs, mp->cregs);
  
  	/* Reset once more. */
  	myri_reset_on(mp->cregs);
  
  	/* Get the supported DVMA burst sizes from our SBUS. */
  	mp->myri_bursts = prom_getintdefault(mp->myri_sdev->bus->prom_node,
  					     "burst-sizes", 0x00);
  
  	if (!sbus_can_burst64(sdev))
  		mp->myri_bursts &= ~(DMA_BURST64);
  
  	DET(("MYRI bursts %02x\n", mp->myri_bursts));
  
  	/* Encode SBUS interrupt level in second control register. */
  	i = prom_getint(sdev->prom_node, "interrupts");
  	if (i == 0)
  		i = 4;
  	DET(("prom_getint(interrupts)==%d, irqlvl set to %04x\n",
  	     i, (1 << i)));
  
  	sbus_writel((1 << i), mp->cregs + MYRICTRL_IRQLVL);
  
  	mp->dev = dev;
  	dev->open = &myri_open;
  	dev->stop = &myri_close;
  	dev->hard_start_xmit = &myri_start_xmit;
  	dev->tx_timeout = &myri_tx_timeout;
  	dev->watchdog_timeo = 5*HZ;
  	dev->get_stats = &myri_get_stats;
  	dev->set_multicast_list = &myri_set_multicast;
  	dev->irq = sdev->irqs[0];
  
  	/* Register interrupt handler now. */
  	DET(("Requesting MYRIcom IRQ line.\n"));
  	if (request_irq(dev->irq, &myri_interrupt,
  			SA_SHIRQ, "MyriCOM Ethernet", (void *) dev)) {
  		printk("MyriCOM: Cannot register interrupt handler.\n");
  		goto err;
  	}
  
  	DET(("ether_setup()\n"));
  	ether_setup(dev);
  
  	dev->mtu		= MYRINET_MTU;
  	dev->change_mtu		= myri_change_mtu;
  	dev->hard_header	= myri_header;
  	dev->rebuild_header	= myri_rebuild_header;
  	dev->hard_header_len	= (ETH_HLEN + MYRI_PAD_LEN);
  	dev->hard_header_cache 	= myri_header_cache;
  	dev->header_cache_update= myri_header_cache_update;
  
  	/* Load code onto the LANai. */
  	DET(("Loading LANAI firmware\n"));
  	myri_load_lanai(mp);
  
  #ifdef MODULE
  	dev->ifindex = dev_new_index();
  	mp->next_module = root_myri_dev;
  	root_myri_dev = mp;
  #endif
  	return 0;
  err:	unregister_netdev(dev);
  	kfree(dev);
  	return -ENODEV;
  }
  
  static int __init myri_sbus_match(struct sbus_dev *sdev)
  {
  	char *name = sdev->prom_name;
  
  	if (!strcmp(name, "MYRICOM,mlanai") ||
  	    !strcmp(name, "myri"))
  		return 1;
  
  	return 0;
  }
  
  static int __init myri_sbus_probe(void)
  {
  	struct net_device *dev = NULL;
  	struct sbus_bus *bus;
  	struct sbus_dev *sdev = 0;
  	static int called;
  	int cards = 0, v;
  
  #ifdef MODULE
  	root_myri_dev = NULL;
  #endif
  
  	if (called)
  		return -ENODEV;
  	called++;
  
  	for_each_sbus(bus) {
  		for_each_sbusdev(sdev, bus) {
  			if (cards)
  				dev = NULL;
  			if (myri_sbus_match(sdev)) {
  				cards++;
  				DET(("Found myricom myrinet as %s\n", sdev->prom_name));
  				if ((v = myri_ether_init(dev, sdev, (cards - 1))))
  					return v;
  			}
  		}
  	}
  	if (!cards)
  		return -ENODEV;
  	return 0;
  }
  
  static void __exit myri_sbus_cleanup(void)
  {
  #ifdef MODULE
  	/* No need to check MOD_IN_USE, as sys_delete_module() checks. */
  	while (root_myri_dev) {
  		struct myri_eth *next = root_myri_dev->next_module;
  
  		unregister_netdev(root_myri_dev->dev);
  		kfree(root_myri_dev->dev);
  		root_myri_dev = next;
  	}
  #endif /* MODULE */
  }
  
  module_init(myri_sbus_probe);
  module_exit(myri_sbus_cleanup);
  MODULE_LICENSE("GPL");
  